diff --git a/sys/netinet/tcp_input.c b/sys/netinet/tcp_input.c index e5f5e09e57d8..3dfdb13994a5 100644 --- a/sys/netinet/tcp_input.c +++ b/sys/netinet/tcp_input.c @@ -1,4250 +1,4250 @@ /*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1994, 1995 * The Regents of the University of California. All rights reserved. * Copyright (c) 2007-2008,2010 * Swinburne University of Technology, Melbourne, Australia. * Copyright (c) 2009-2010 Lawrence Stewart * Copyright (c) 2010 The FreeBSD Foundation * Copyright (c) 2010-2011 Juniper Networks, Inc. * All rights reserved. * * Portions of this software were developed at the Centre for Advanced Internet * Architectures, Swinburne University of Technology, by Lawrence Stewart, * James Healy and David Hayes, made possible in part by a grant from the Cisco * University Research Program Fund at Community Foundation Silicon Valley. * * Portions of this software were developed at the Centre for Advanced * Internet Architectures, Swinburne University of Technology, Melbourne, * Australia by David Hayes under sponsorship from the FreeBSD Foundation. * * Portions of this software were developed by Robert N. M. Watson under * contract to Juniper Networks, Inc. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include #include "opt_inet.h" #include "opt_inet6.h" #include "opt_ipsec.h" #include "opt_rss.h" #include #include #include #ifdef TCP_HHOOK #include #endif #include #include #include /* for proc0 declaration */ #include #include #include #include #include #include #include #include #include #include #include /* before tcp_seq.h, for tcp_random18() */ #include #include #include #include #include #include #define TCPSTATES /* for logging */ #include #include #include #include #include #include #include /* required for icmp_var.h */ #include /* for ICMP_BANDLIM */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef TCPPCAP #include #endif #include #ifdef TCP_OFFLOAD #include #endif #include #include #include #include #include const int tcprexmtthresh = 3; VNET_DEFINE(int, tcp_log_in_vain) = 0; SYSCTL_INT(_net_inet_tcp, OID_AUTO, log_in_vain, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_log_in_vain), 0, "Log all incoming TCP segments to closed ports"); VNET_DEFINE(int, blackhole) = 0; #define V_blackhole VNET(blackhole) SYSCTL_INT(_net_inet_tcp, OID_AUTO, blackhole, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(blackhole), 0, "Do not send RST on segments to closed ports"); VNET_DEFINE(bool, blackhole_local) = false; #define V_blackhole_local VNET(blackhole_local) SYSCTL_BOOL(_net_inet_tcp, OID_AUTO, blackhole_local, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(blackhole_local), false, "Enforce net.inet.tcp.blackhole for locally originated packets"); VNET_DEFINE(int, tcp_delack_enabled) = 1; SYSCTL_INT(_net_inet_tcp, OID_AUTO, delayed_ack, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_delack_enabled), 0, "Delay ACK to try and piggyback it onto a data packet"); VNET_DEFINE(int, drop_synfin) = 0; SYSCTL_INT(_net_inet_tcp, OID_AUTO, drop_synfin, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(drop_synfin), 0, "Drop TCP packets with SYN+FIN set"); VNET_DEFINE(int, tcp_do_prr) = 1; SYSCTL_INT(_net_inet_tcp, OID_AUTO, do_prr, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_do_prr), 1, "Enable Proportional Rate Reduction per RFC 6937"); VNET_DEFINE(int, tcp_do_newcwv) = 0; SYSCTL_INT(_net_inet_tcp, OID_AUTO, newcwv, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_do_newcwv), 0, "Enable New Congestion Window Validation per RFC7661"); VNET_DEFINE(int, tcp_do_rfc3042) = 1; SYSCTL_INT(_net_inet_tcp, OID_AUTO, rfc3042, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_do_rfc3042), 0, "Enable RFC 3042 (Limited Transmit)"); VNET_DEFINE(int, tcp_do_rfc3390) = 1; SYSCTL_INT(_net_inet_tcp, OID_AUTO, rfc3390, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_do_rfc3390), 0, "Enable RFC 3390 (Increasing TCP's Initial Congestion Window)"); VNET_DEFINE(int, tcp_initcwnd_segments) = 10; SYSCTL_INT(_net_inet_tcp, OID_AUTO, initcwnd_segments, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_initcwnd_segments), 0, "Slow-start flight size (initial congestion window) in number of segments"); VNET_DEFINE(int, tcp_do_rfc3465) = 1; SYSCTL_INT(_net_inet_tcp, OID_AUTO, rfc3465, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_do_rfc3465), 0, "Enable RFC 3465 (Appropriate Byte Counting)"); VNET_DEFINE(int, tcp_abc_l_var) = 2; SYSCTL_INT(_net_inet_tcp, OID_AUTO, abc_l_var, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_abc_l_var), 2, "Cap the max cwnd increment during slow-start to this number of segments"); VNET_DEFINE(int, tcp_insecure_syn) = 0; SYSCTL_INT(_net_inet_tcp, OID_AUTO, insecure_syn, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_insecure_syn), 0, "Follow RFC793 instead of RFC5961 criteria for accepting SYN packets"); VNET_DEFINE(int, tcp_insecure_rst) = 0; SYSCTL_INT(_net_inet_tcp, OID_AUTO, insecure_rst, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_insecure_rst), 0, "Follow RFC793 instead of RFC5961 criteria for accepting RST packets"); VNET_DEFINE(int, tcp_insecure_ack) = 0; SYSCTL_INT(_net_inet_tcp, OID_AUTO, insecure_ack, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_insecure_ack), 0, "Follow RFC793 criteria for validating SEG.ACK"); VNET_DEFINE(int, tcp_recvspace) = 1024*64; #define V_tcp_recvspace VNET(tcp_recvspace) SYSCTL_INT(_net_inet_tcp, TCPCTL_RECVSPACE, recvspace, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_recvspace), 0, "Initial receive socket buffer size"); VNET_DEFINE(int, tcp_do_autorcvbuf) = 1; SYSCTL_INT(_net_inet_tcp, OID_AUTO, recvbuf_auto, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_do_autorcvbuf), 0, "Enable automatic receive buffer sizing"); VNET_DEFINE(int, tcp_autorcvbuf_max) = 2*1024*1024; SYSCTL_INT(_net_inet_tcp, OID_AUTO, recvbuf_max, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_autorcvbuf_max), 0, "Max size of automatic receive buffer"); VNET_DEFINE(struct inpcbinfo, tcbinfo); /* * TCP statistics are stored in an array of counter(9)s, which size matches * size of struct tcpstat. TCP running connection count is a regular array. */ VNET_PCPUSTAT_DEFINE(struct tcpstat, tcpstat); SYSCTL_VNET_PCPUSTAT(_net_inet_tcp, TCPCTL_STATS, stats, struct tcpstat, tcpstat, "TCP statistics (struct tcpstat, netinet/tcp_var.h)"); VNET_DEFINE(counter_u64_t, tcps_states[TCP_NSTATES]); SYSCTL_COUNTER_U64_ARRAY(_net_inet_tcp, TCPCTL_STATES, states, CTLFLAG_RD | CTLFLAG_VNET, &VNET_NAME(tcps_states)[0], TCP_NSTATES, "TCP connection counts by TCP state"); /* * Kernel module interface for updating tcpstat. The first argument is an index * into tcpstat treated as an array. */ void kmod_tcpstat_add(int statnum, int val) { counter_u64_add(VNET(tcpstat)[statnum], val); } /* * Make sure that we only start a SACK loss recovery when * receiving a duplicate ACK with a SACK block, and also * complete SACK loss recovery in case the other end * reneges. */ static bool inline tcp_is_sack_recovery(struct tcpcb *tp, struct tcpopt *to) { return ((tp->t_flags & TF_SACK_PERMIT) && ((to->to_flags & TOF_SACK) || (!TAILQ_EMPTY(&tp->snd_holes)))); } #ifdef TCP_HHOOK /* * Wrapper for the TCP established input helper hook. */ void hhook_run_tcp_est_in(struct tcpcb *tp, struct tcphdr *th, struct tcpopt *to) { struct tcp_hhook_data hhook_data; if (V_tcp_hhh[HHOOK_TCP_EST_IN]->hhh_nhooks > 0) { hhook_data.tp = tp; hhook_data.th = th; hhook_data.to = to; hhook_run_hooks(V_tcp_hhh[HHOOK_TCP_EST_IN], &hhook_data, &tp->t_osd); } } #endif /* * CC wrapper hook functions */ void cc_ack_received(struct tcpcb *tp, struct tcphdr *th, uint16_t nsegs, uint16_t type) { #ifdef STATS int32_t gput; #endif INP_WLOCK_ASSERT(tptoinpcb(tp)); tp->t_ccv.nsegs = nsegs; tp->t_ccv.bytes_this_ack = BYTES_THIS_ACK(tp, th); if ((!V_tcp_do_newcwv && (tp->snd_cwnd <= tp->snd_wnd)) || (V_tcp_do_newcwv && (tp->snd_cwnd <= tp->snd_wnd) && (tp->snd_cwnd < (tcp_compute_pipe(tp) * 2)))) tp->t_ccv.flags |= CCF_CWND_LIMITED; else tp->t_ccv.flags &= ~CCF_CWND_LIMITED; if (type == CC_ACK) { #ifdef STATS stats_voi_update_abs_s32(tp->t_stats, VOI_TCP_CALCFRWINDIFF, ((int32_t)tp->snd_cwnd) - tp->snd_wnd); if (!IN_RECOVERY(tp->t_flags)) stats_voi_update_abs_u32(tp->t_stats, VOI_TCP_ACKLEN, tp->t_ccv.bytes_this_ack / (tcp_maxseg(tp) * nsegs)); if ((tp->t_flags & TF_GPUTINPROG) && SEQ_GEQ(th->th_ack, tp->gput_ack)) { /* * Compute goodput in bits per millisecond. */ gput = (((int64_t)SEQ_SUB(th->th_ack, tp->gput_seq)) << 3) / max(1, tcp_ts_getticks() - tp->gput_ts); stats_voi_update_abs_u32(tp->t_stats, VOI_TCP_GPUT, gput); /* * XXXLAS: This is a temporary hack, and should be * chained off VOI_TCP_GPUT when stats(9) grows an API * to deal with chained VOIs. */ if (tp->t_stats_gput_prev > 0) stats_voi_update_abs_s32(tp->t_stats, VOI_TCP_GPUT_ND, ((gput - tp->t_stats_gput_prev) * 100) / tp->t_stats_gput_prev); tp->t_flags &= ~TF_GPUTINPROG; tp->t_stats_gput_prev = gput; } #endif /* STATS */ if (tp->snd_cwnd > tp->snd_ssthresh) { tp->t_bytes_acked += tp->t_ccv.bytes_this_ack; if (tp->t_bytes_acked >= tp->snd_cwnd) { tp->t_bytes_acked -= tp->snd_cwnd; tp->t_ccv.flags |= CCF_ABC_SENTAWND; } } else { tp->t_ccv.flags &= ~CCF_ABC_SENTAWND; tp->t_bytes_acked = 0; } } if (CC_ALGO(tp)->ack_received != NULL) { /* XXXLAS: Find a way to live without this */ tp->t_ccv.curack = th->th_ack; CC_ALGO(tp)->ack_received(&tp->t_ccv, type); } #ifdef STATS stats_voi_update_abs_ulong(tp->t_stats, VOI_TCP_LCWIN, tp->snd_cwnd); #endif } void cc_conn_init(struct tcpcb *tp) { struct hc_metrics_lite metrics; struct inpcb *inp = tptoinpcb(tp); u_int maxseg; int rtt; INP_WLOCK_ASSERT(inp); tcp_hc_get(&inp->inp_inc, &metrics); maxseg = tcp_maxseg(tp); if (tp->t_srtt == 0 && (rtt = metrics.rmx_rtt)) { tp->t_srtt = rtt; TCPSTAT_INC(tcps_usedrtt); if (metrics.rmx_rttvar) { tp->t_rttvar = metrics.rmx_rttvar; TCPSTAT_INC(tcps_usedrttvar); } else { /* default variation is +- 1 rtt */ tp->t_rttvar = tp->t_srtt * TCP_RTTVAR_SCALE / TCP_RTT_SCALE; } TCPT_RANGESET(tp->t_rxtcur, ((tp->t_srtt >> 2) + tp->t_rttvar) >> 1, tp->t_rttmin, TCPTV_REXMTMAX); } if (metrics.rmx_ssthresh) { /* * There's some sort of gateway or interface * buffer limit on the path. Use this to set * the slow start threshold, but set the * threshold to no less than 2*mss. */ tp->snd_ssthresh = max(2 * maxseg, metrics.rmx_ssthresh); TCPSTAT_INC(tcps_usedssthresh); } /* * Set the initial slow-start flight size. * * If a SYN or SYN/ACK was lost and retransmitted, we have to * reduce the initial CWND to one segment as congestion is likely * requiring us to be cautious. */ if (tp->snd_cwnd == 1) tp->snd_cwnd = maxseg; /* SYN(-ACK) lost */ else tp->snd_cwnd = tcp_compute_initwnd(maxseg); if (CC_ALGO(tp)->conn_init != NULL) CC_ALGO(tp)->conn_init(&tp->t_ccv); } void inline cc_cong_signal(struct tcpcb *tp, struct tcphdr *th, uint32_t type) { INP_WLOCK_ASSERT(tptoinpcb(tp)); #ifdef STATS stats_voi_update_abs_u32(tp->t_stats, VOI_TCP_CSIG, type); #endif switch(type) { case CC_NDUPACK: if (!IN_FASTRECOVERY(tp->t_flags)) { tp->snd_recover = tp->snd_max; if (tp->t_flags2 & TF2_ECN_PERMIT) tp->t_flags2 |= TF2_ECN_SND_CWR; } break; case CC_ECN: if (!IN_CONGRECOVERY(tp->t_flags) || /* * Allow ECN reaction on ACK to CWR, if * that data segment was also CE marked. */ SEQ_GEQ(th->th_ack, tp->snd_recover)) { EXIT_CONGRECOVERY(tp->t_flags); TCPSTAT_INC(tcps_ecn_rcwnd); tp->snd_recover = tp->snd_max + 1; if (tp->t_flags2 & TF2_ECN_PERMIT) tp->t_flags2 |= TF2_ECN_SND_CWR; } break; case CC_RTO: tp->t_dupacks = 0; tp->t_bytes_acked = 0; EXIT_RECOVERY(tp->t_flags); if (tp->t_flags2 & TF2_ECN_PERMIT) tp->t_flags2 |= TF2_ECN_SND_CWR; break; case CC_RTO_ERR: TCPSTAT_INC(tcps_sndrexmitbad); /* RTO was unnecessary, so reset everything. */ tp->snd_cwnd = tp->snd_cwnd_prev; tp->snd_ssthresh = tp->snd_ssthresh_prev; tp->snd_recover = tp->snd_recover_prev; if (tp->t_flags & TF_WASFRECOVERY) ENTER_FASTRECOVERY(tp->t_flags); if (tp->t_flags & TF_WASCRECOVERY) ENTER_CONGRECOVERY(tp->t_flags); tp->snd_nxt = tp->snd_max; tp->t_flags &= ~TF_PREVVALID; tp->t_badrxtwin = 0; break; } if (SEQ_LT(tp->snd_fack, tp->snd_una) || SEQ_GT(tp->snd_fack, tp->snd_max)) { tp->snd_fack = tp->snd_una; } if (CC_ALGO(tp)->cong_signal != NULL) { if (th != NULL) tp->t_ccv.curack = th->th_ack; CC_ALGO(tp)->cong_signal(&tp->t_ccv, type); } } void inline cc_post_recovery(struct tcpcb *tp, struct tcphdr *th) { INP_WLOCK_ASSERT(tptoinpcb(tp)); if (CC_ALGO(tp)->post_recovery != NULL) { if (SEQ_LT(tp->snd_fack, th->th_ack) || SEQ_GT(tp->snd_fack, tp->snd_max)) { tp->snd_fack = th->th_ack; } tp->t_ccv.curack = th->th_ack; CC_ALGO(tp)->post_recovery(&tp->t_ccv); } EXIT_RECOVERY(tp->t_flags); tp->t_bytes_acked = 0; tp->sackhint.delivered_data = 0; tp->sackhint.prr_delivered = 0; tp->sackhint.prr_out = 0; } /* * Indicate whether this ack should be delayed. We can delay the ack if * following conditions are met: * - There is no delayed ack timer in progress. * - Our last ack wasn't a 0-sized window. We never want to delay * the ack that opens up a 0-sized window. * - LRO wasn't used for this segment. We make sure by checking that the * segment size is not larger than the MSS. */ #define DELAY_ACK(tp, tlen) \ ((!tcp_timer_active(tp, TT_DELACK) && \ (tp->t_flags & TF_RXWIN0SENT) == 0) && \ (tlen <= tp->t_maxseg) && \ (V_tcp_delack_enabled || (tp->t_flags & TF_NEEDSYN))) void inline cc_ecnpkt_handler_flags(struct tcpcb *tp, uint16_t flags, uint8_t iptos) { INP_WLOCK_ASSERT(tptoinpcb(tp)); if (CC_ALGO(tp)->ecnpkt_handler != NULL) { switch (iptos & IPTOS_ECN_MASK) { case IPTOS_ECN_CE: tp->t_ccv.flags |= CCF_IPHDR_CE; break; case IPTOS_ECN_ECT0: /* FALLTHROUGH */ case IPTOS_ECN_ECT1: /* FALLTHROUGH */ case IPTOS_ECN_NOTECT: tp->t_ccv.flags &= ~CCF_IPHDR_CE; break; } if (flags & TH_CWR) tp->t_ccv.flags |= CCF_TCPHDR_CWR; else tp->t_ccv.flags &= ~CCF_TCPHDR_CWR; CC_ALGO(tp)->ecnpkt_handler(&tp->t_ccv); if (tp->t_ccv.flags & CCF_ACKNOW) { tcp_timer_activate(tp, TT_DELACK, tcp_delacktime); tp->t_flags |= TF_ACKNOW; } } } void inline cc_ecnpkt_handler(struct tcpcb *tp, struct tcphdr *th, uint8_t iptos) { cc_ecnpkt_handler_flags(tp, tcp_get_flags(th), iptos); } /* * TCP input handling is split into multiple parts: * tcp6_input is a thin wrapper around tcp_input for the extended * ip6_protox[] call format in ip6_input * tcp_input handles primary segment validation, inpcb lookup and * SYN processing on listen sockets * tcp_do_segment processes the ACK and text of the segment for * establishing, established and closing connections */ #ifdef INET6 int tcp6_input_with_port(struct mbuf **mp, int *offp, int proto, uint16_t port) { struct mbuf *m; struct in6_ifaddr *ia6; struct ip6_hdr *ip6; m = *mp; if (m->m_len < *offp + sizeof(struct tcphdr)) { m = m_pullup(m, *offp + sizeof(struct tcphdr)); if (m == NULL) { *mp = m; TCPSTAT_INC(tcps_rcvshort); return (IPPROTO_DONE); } } /* * draft-itojun-ipv6-tcp-to-anycast * better place to put this in? */ ip6 = mtod(m, struct ip6_hdr *); ia6 = in6ifa_ifwithaddr(&ip6->ip6_dst, 0 /* XXX */, false); if (ia6 && (ia6->ia6_flags & IN6_IFF_ANYCAST)) { icmp6_error(m, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_ADDR, (caddr_t)&ip6->ip6_dst - (caddr_t)ip6); *mp = NULL; return (IPPROTO_DONE); } *mp = m; return (tcp_input_with_port(mp, offp, proto, port)); } int tcp6_input(struct mbuf **mp, int *offp, int proto) { return(tcp6_input_with_port(mp, offp, proto, 0)); } #endif /* INET6 */ int tcp_input_with_port(struct mbuf **mp, int *offp, int proto, uint16_t port) { struct mbuf *m = *mp; struct tcphdr *th = NULL; struct ip *ip = NULL; struct inpcb *inp = NULL; struct tcpcb *tp = NULL; struct socket *so = NULL; u_char *optp = NULL; int off0; int optlen = 0; #ifdef INET int len; uint8_t ipttl; #endif int tlen = 0, off; int drop_hdrlen; int thflags; int rstreason = 0; /* For badport_bandlim accounting purposes */ int lookupflag; uint8_t iptos; struct m_tag *fwd_tag = NULL; #ifdef INET6 struct ip6_hdr *ip6 = NULL; int isipv6; #else const void *ip6 = NULL; #endif /* INET6 */ struct tcpopt to; /* options in this segment */ char *s = NULL; /* address and port logging */ NET_EPOCH_ASSERT(); #ifdef INET6 isipv6 = (mtod(m, struct ip *)->ip_v == 6) ? 1 : 0; #endif off0 = *offp; m = *mp; *mp = NULL; to.to_flags = 0; TCPSTAT_INC(tcps_rcvtotal); m->m_pkthdr.tcp_tun_port = port; #ifdef INET6 if (isipv6) { ip6 = mtod(m, struct ip6_hdr *); th = (struct tcphdr *)((caddr_t)ip6 + off0); tlen = sizeof(*ip6) + ntohs(ip6->ip6_plen) - off0; if (port) goto skip6_csum; if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID_IPV6) { if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) th->th_sum = m->m_pkthdr.csum_data; else th->th_sum = in6_cksum_pseudo(ip6, tlen, IPPROTO_TCP, m->m_pkthdr.csum_data); th->th_sum ^= 0xffff; } else th->th_sum = in6_cksum(m, IPPROTO_TCP, off0, tlen); if (th->th_sum) { TCPSTAT_INC(tcps_rcvbadsum); goto drop; } skip6_csum: /* * Be proactive about unspecified IPv6 address in source. * As we use all-zero to indicate unbounded/unconnected pcb, * unspecified IPv6 address can be used to confuse us. * * Note that packets with unspecified IPv6 destination is * already dropped in ip6_input. */ KASSERT(!IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst), ("%s: unspecified destination v6 address", __func__)); if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src)) { IP6STAT_INC(ip6s_badscope); /* XXX */ goto drop; } iptos = IPV6_TRAFFIC_CLASS(ip6); } #endif #if defined(INET) && defined(INET6) else #endif #ifdef INET { /* * Get IP and TCP header together in first mbuf. * Note: IP leaves IP header in first mbuf. */ if (off0 > sizeof (struct ip)) { ip_stripoptions(m); off0 = sizeof(struct ip); } if (m->m_len < sizeof (struct tcpiphdr)) { if ((m = m_pullup(m, sizeof (struct tcpiphdr))) == NULL) { TCPSTAT_INC(tcps_rcvshort); return (IPPROTO_DONE); } } ip = mtod(m, struct ip *); th = (struct tcphdr *)((caddr_t)ip + off0); tlen = ntohs(ip->ip_len) - off0; iptos = ip->ip_tos; if (port) goto skip_csum; if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) { if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) th->th_sum = m->m_pkthdr.csum_data; else th->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, htonl(m->m_pkthdr.csum_data + tlen + IPPROTO_TCP)); th->th_sum ^= 0xffff; } else { struct ipovly *ipov = (struct ipovly *)ip; /* * Checksum extended TCP header and data. */ len = off0 + tlen; ipttl = ip->ip_ttl; bzero(ipov->ih_x1, sizeof(ipov->ih_x1)); ipov->ih_len = htons(tlen); th->th_sum = in_cksum(m, len); /* Reset length for SDT probes. */ ip->ip_len = htons(len); /* Reset TOS bits */ ip->ip_tos = iptos; /* Re-initialization for later version check */ ip->ip_ttl = ipttl; ip->ip_v = IPVERSION; ip->ip_hl = off0 >> 2; } skip_csum: if (th->th_sum && (port == 0)) { TCPSTAT_INC(tcps_rcvbadsum); goto drop; } KASSERT(ip->ip_dst.s_addr != INADDR_ANY, ("%s: unspecified destination v4 address", __func__)); if (__predict_false(ip->ip_src.s_addr == INADDR_ANY)) { IPSTAT_INC(ips_badaddr); goto drop; } } #endif /* INET */ /* * Check that TCP offset makes sense, * pull out TCP options and adjust length. XXX */ off = th->th_off << 2; if (off < sizeof (struct tcphdr) || off > tlen) { TCPSTAT_INC(tcps_rcvbadoff); goto drop; } tlen -= off; /* tlen is used instead of ti->ti_len */ if (off > sizeof (struct tcphdr)) { #ifdef INET6 if (isipv6) { if (m->m_len < off0 + off) { m = m_pullup(m, off0 + off); if (m == NULL) { TCPSTAT_INC(tcps_rcvshort); return (IPPROTO_DONE); } } ip6 = mtod(m, struct ip6_hdr *); th = (struct tcphdr *)((caddr_t)ip6 + off0); } #endif #if defined(INET) && defined(INET6) else #endif #ifdef INET { if (m->m_len < sizeof(struct ip) + off) { if ((m = m_pullup(m, sizeof (struct ip) + off)) == NULL) { TCPSTAT_INC(tcps_rcvshort); return (IPPROTO_DONE); } ip = mtod(m, struct ip *); th = (struct tcphdr *)((caddr_t)ip + off0); } } #endif optlen = off - sizeof (struct tcphdr); optp = (u_char *)(th + 1); } thflags = tcp_get_flags(th); /* * Convert TCP protocol specific fields to host format. */ tcp_fields_to_host(th); /* * Delay dropping TCP, IP headers, IPv6 ext headers, and TCP options. */ drop_hdrlen = off0 + off; /* * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain. */ if ( #ifdef INET6 (isipv6 && (m->m_flags & M_IP6_NEXTHOP)) #ifdef INET || (!isipv6 && (m->m_flags & M_IP_NEXTHOP)) #endif #endif #if defined(INET) && !defined(INET6) (m->m_flags & M_IP_NEXTHOP) #endif ) fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL); /* * For initial SYN packets we don't need write lock on matching * PCB, be it a listening one or a synchronized one. The packet * shall not modify its state. */ lookupflag = INPLOOKUP_WILDCARD | ((thflags & (TH_ACK|TH_SYN)) == TH_SYN ? INPLOOKUP_RLOCKPCB : INPLOOKUP_WLOCKPCB); findpcb: tp = NULL; #ifdef INET6 if (isipv6 && fwd_tag != NULL) { struct sockaddr_in6 *next_hop6; next_hop6 = (struct sockaddr_in6 *)(fwd_tag + 1); /* * Transparently forwarded. Pretend to be the destination. * Already got one like this? */ inp = in6_pcblookup_mbuf(&V_tcbinfo, &ip6->ip6_src, th->th_sport, &ip6->ip6_dst, th->th_dport, lookupflag & ~INPLOOKUP_WILDCARD, m->m_pkthdr.rcvif, m); if (!inp) { /* * It's new. Try to find the ambushing socket. * Because we've rewritten the destination address, * any hardware-generated hash is ignored. */ inp = in6_pcblookup(&V_tcbinfo, &ip6->ip6_src, th->th_sport, &next_hop6->sin6_addr, next_hop6->sin6_port ? ntohs(next_hop6->sin6_port) : th->th_dport, lookupflag, m->m_pkthdr.rcvif); } } else if (isipv6) { inp = in6_pcblookup_mbuf(&V_tcbinfo, &ip6->ip6_src, th->th_sport, &ip6->ip6_dst, th->th_dport, lookupflag, m->m_pkthdr.rcvif, m); } #endif /* INET6 */ #if defined(INET6) && defined(INET) else #endif #ifdef INET if (fwd_tag != NULL) { struct sockaddr_in *next_hop; next_hop = (struct sockaddr_in *)(fwd_tag+1); /* * Transparently forwarded. Pretend to be the destination. * already got one like this? */ inp = in_pcblookup_mbuf(&V_tcbinfo, ip->ip_src, th->th_sport, ip->ip_dst, th->th_dport, lookupflag & ~INPLOOKUP_WILDCARD, m->m_pkthdr.rcvif, m); if (!inp) { /* * It's new. Try to find the ambushing socket. * Because we've rewritten the destination address, * any hardware-generated hash is ignored. */ inp = in_pcblookup(&V_tcbinfo, ip->ip_src, th->th_sport, next_hop->sin_addr, next_hop->sin_port ? ntohs(next_hop->sin_port) : th->th_dport, lookupflag, m->m_pkthdr.rcvif); } } else inp = in_pcblookup_mbuf(&V_tcbinfo, ip->ip_src, th->th_sport, ip->ip_dst, th->th_dport, lookupflag, m->m_pkthdr.rcvif, m); #endif /* INET */ /* * If the INPCB does not exist then all data in the incoming * segment is discarded and an appropriate RST is sent back. * XXX MRT Send RST using which routing table? */ if (inp == NULL) { if (rstreason != 0) { /* We came here after second (safety) lookup. */ MPASS((lookupflag & INPLOOKUP_WILDCARD) == 0); goto dropwithreset; } /* * Log communication attempts to ports that are not * in use. */ if ((V_tcp_log_in_vain == 1 && (thflags & TH_SYN)) || V_tcp_log_in_vain == 2) { if ((s = tcp_log_vain(NULL, th, (void *)ip, ip6))) log(LOG_INFO, "%s; %s: Connection attempt " "to closed port\n", s, __func__); } rstreason = BANDLIM_RST_CLOSEDPORT; goto dropwithreset; } INP_LOCK_ASSERT(inp); if ((inp->inp_flowtype == M_HASHTYPE_NONE) && !SOLISTENING(inp->inp_socket)) { if (M_HASHTYPE_GET(m) != M_HASHTYPE_NONE) { inp->inp_flowid = m->m_pkthdr.flowid; inp->inp_flowtype = M_HASHTYPE_GET(m); #ifdef RSS } else { /* assign flowid by software RSS hash */ #ifdef INET6 if (isipv6) { rss_proto_software_hash_v6(&inp->in6p_faddr, &inp->in6p_laddr, inp->inp_fport, inp->inp_lport, IPPROTO_TCP, &inp->inp_flowid, &inp->inp_flowtype); } else #endif /* INET6 */ { rss_proto_software_hash_v4(inp->inp_faddr, inp->inp_laddr, inp->inp_fport, inp->inp_lport, IPPROTO_TCP, &inp->inp_flowid, &inp->inp_flowtype); } #endif /* RSS */ } } #if defined(IPSEC) || defined(IPSEC_SUPPORT) #ifdef INET6 if (isipv6 && IPSEC_ENABLED(ipv6) && IPSEC_CHECK_POLICY(ipv6, m, inp) != 0) { goto dropunlock; } #ifdef INET else #endif #endif /* INET6 */ #ifdef INET if (IPSEC_ENABLED(ipv4) && IPSEC_CHECK_POLICY(ipv4, m, inp) != 0) { goto dropunlock; } #endif /* INET */ #endif /* IPSEC */ /* * Check the minimum TTL for socket. */ if (inp->inp_ip_minttl != 0) { #ifdef INET6 if (isipv6) { if (inp->inp_ip_minttl > ip6->ip6_hlim) goto dropunlock; } else #endif if (inp->inp_ip_minttl > ip->ip_ttl) goto dropunlock; } tp = intotcpcb(inp); switch (tp->t_state) { case TCPS_TIME_WAIT: /* * A previous connection in TIMEWAIT state is supposed to catch * stray or duplicate segments arriving late. If this segment * was a legitimate new connection attempt, the old INPCB gets * removed and we can try again to find a listening socket. */ tcp_dooptions(&to, optp, optlen, (thflags & TH_SYN) ? TO_SYN : 0); /* * tcp_twcheck unlocks the inp always, and frees the m if fails. */ if (tcp_twcheck(inp, &to, th, m, tlen)) goto findpcb; return (IPPROTO_DONE); case TCPS_CLOSED: /* * The TCPCB may no longer exist if the connection is winding * down or it is in the CLOSED state. Either way we drop the * segment and send an appropriate response. */ rstreason = BANDLIM_RST_CLOSEDPORT; goto dropwithreset; } if ((tp->t_port != port) && (tp->t_state > TCPS_LISTEN)) { rstreason = BANDLIM_RST_CLOSEDPORT; goto dropwithreset; } #ifdef TCP_OFFLOAD if (tp->t_flags & TF_TOE) { tcp_offload_input(tp, m); m = NULL; /* consumed by the TOE driver */ goto dropunlock; } #endif #ifdef MAC if (mac_inpcb_check_deliver(inp, m)) goto dropunlock; #endif so = inp->inp_socket; KASSERT(so != NULL, ("%s: so == NULL", __func__)); /* * When the socket is accepting connections (the INPCB is in LISTEN * state) we look into the SYN cache if this is a new connection * attempt or the completion of a previous one. */ KASSERT(tp->t_state == TCPS_LISTEN || !SOLISTENING(so), ("%s: so accepting but tp %p not listening", __func__, tp)); if (tp->t_state == TCPS_LISTEN && SOLISTENING(so)) { struct in_conninfo inc; bzero(&inc, sizeof(inc)); #ifdef INET6 if (isipv6) { inc.inc_flags |= INC_ISIPV6; if (inp->inp_inc.inc_flags & INC_IPV6MINMTU) inc.inc_flags |= INC_IPV6MINMTU; inc.inc6_faddr = ip6->ip6_src; inc.inc6_laddr = ip6->ip6_dst; } else #endif { inc.inc_faddr = ip->ip_src; inc.inc_laddr = ip->ip_dst; } inc.inc_fport = th->th_sport; inc.inc_lport = th->th_dport; inc.inc_fibnum = so->so_fibnum; /* * Check for an existing connection attempt in syncache if * the flag is only ACK. A successful lookup creates a new * socket appended to the listen queue in SYN_RECEIVED state. */ if ((thflags & (TH_RST|TH_ACK|TH_SYN)) == TH_ACK) { /* * Parse the TCP options here because * syncookies need access to the reflected * timestamp. */ tcp_dooptions(&to, optp, optlen, 0); /* * NB: syncache_expand() doesn't unlock inp. */ rstreason = syncache_expand(&inc, &to, th, &so, m, port); if (rstreason < 0) { /* * A failing TCP MD5 signature comparison * must result in the segment being dropped * and must not produce any response back * to the sender. */ goto dropunlock; } else if (rstreason == 0) { /* * No syncache entry, or ACK was not for our * SYN/ACK. Do our protection against double * ACK. If peer sent us 2 ACKs, then for the * first one syncache_expand() successfully * converted syncache entry into a socket, * while we were waiting on the inpcb lock. We * don't want to sent RST for the second ACK, * so we perform second lookup without wildcard * match, hoping to find the new socket. If * the ACK is stray indeed, rstreason would * hint the above code that the lookup was a * second attempt. * * NB: syncache did its own logging * of the failure cause. */ INP_WUNLOCK(inp); rstreason = BANDLIM_RST_OPENPORT; lookupflag &= ~INPLOOKUP_WILDCARD; goto findpcb; } tfo_socket_result: if (so == NULL) { /* * We completed the 3-way handshake * but could not allocate a socket * either due to memory shortage, * listen queue length limits or * global socket limits. Send RST * or wait and have the remote end * retransmit the ACK for another * try. */ if ((s = tcp_log_addrs(&inc, th, NULL, NULL))) log(LOG_DEBUG, "%s; %s: Listen socket: " "Socket allocation failed due to " "limits or memory shortage, %s\n", s, __func__, V_tcp_sc_rst_sock_fail ? "sending RST" : "try again"); if (V_tcp_sc_rst_sock_fail) { rstreason = BANDLIM_UNLIMITED; goto dropwithreset; } else goto dropunlock; } /* * Socket is created in state SYN_RECEIVED. * Unlock the listen socket, lock the newly * created socket and update the tp variable. * If we came here via jump to tfo_socket_result, * then listening socket is read-locked. */ INP_UNLOCK(inp); /* listen socket */ inp = sotoinpcb(so); /* * New connection inpcb is already locked by * syncache_expand(). */ INP_WLOCK_ASSERT(inp); tp = intotcpcb(inp); KASSERT(tp->t_state == TCPS_SYN_RECEIVED, ("%s: ", __func__)); /* * Process the segment and the data it * contains. tcp_do_segment() consumes * the mbuf chain and unlocks the inpcb. */ TCP_PROBE5(receive, NULL, tp, m, tp, th); tp->t_fb->tfb_tcp_do_segment(tp, m, th, drop_hdrlen, tlen, iptos); return (IPPROTO_DONE); } /* * Segment flag validation for new connection attempts: * * Our (SYN|ACK) response was rejected. * Check with syncache and remove entry to prevent * retransmits. * * NB: syncache_chkrst does its own logging of failure * causes. */ if (thflags & TH_RST) { syncache_chkrst(&inc, th, m, port); goto dropunlock; } /* * We can't do anything without SYN. */ if ((thflags & TH_SYN) == 0) { if ((s = tcp_log_addrs(&inc, th, NULL, NULL))) log(LOG_DEBUG, "%s; %s: Listen socket: " "SYN is missing, segment ignored\n", s, __func__); TCPSTAT_INC(tcps_badsyn); goto dropunlock; } /* * (SYN|ACK) is bogus on a listen socket. */ if (thflags & TH_ACK) { if ((s = tcp_log_addrs(&inc, th, NULL, NULL))) log(LOG_DEBUG, "%s; %s: Listen socket: " "SYN|ACK invalid, segment rejected\n", s, __func__); syncache_badack(&inc, port); /* XXX: Not needed! */ TCPSTAT_INC(tcps_badsyn); rstreason = BANDLIM_RST_OPENPORT; goto dropwithreset; } /* * If the drop_synfin option is enabled, drop all * segments with both the SYN and FIN bits set. * This prevents e.g. nmap from identifying the * TCP/IP stack. * XXX: Poor reasoning. nmap has other methods * and is constantly refining its stack detection * strategies. * XXX: This is a violation of the TCP specification * and was used by RFC1644. */ if ((thflags & TH_FIN) && V_drop_synfin) { if ((s = tcp_log_addrs(&inc, th, NULL, NULL))) log(LOG_DEBUG, "%s; %s: Listen socket: " "SYN|FIN segment ignored (based on " "sysctl setting)\n", s, __func__); TCPSTAT_INC(tcps_badsyn); goto dropunlock; } /* * Segment's flags are (SYN) or (SYN|FIN). * * TH_PUSH, TH_URG, TH_ECE, TH_CWR are ignored * as they do not affect the state of the TCP FSM. * The data pointed to by TH_URG and th_urp is ignored. */ KASSERT((thflags & (TH_RST|TH_ACK)) == 0, ("%s: Listen socket: TH_RST or TH_ACK set", __func__)); KASSERT(thflags & (TH_SYN), ("%s: Listen socket: TH_SYN not set", __func__)); INP_RLOCK_ASSERT(inp); #ifdef INET6 /* * If deprecated address is forbidden, * we do not accept SYN to deprecated interface * address to prevent any new inbound connection from * getting established. * When we do not accept SYN, we send a TCP RST, * with deprecated source address (instead of dropping * it). We compromise it as it is much better for peer * to send a RST, and RST will be the final packet * for the exchange. * * If we do not forbid deprecated addresses, we accept * the SYN packet. RFC2462 does not suggest dropping * SYN in this case. * If we decipher RFC2462 5.5.4, it says like this: * 1. use of deprecated addr with existing * communication is okay - "SHOULD continue to be * used" * 2. use of it with new communication: * (2a) "SHOULD NOT be used if alternate address * with sufficient scope is available" * (2b) nothing mentioned otherwise. * Here we fall into (2b) case as we have no choice in * our source address selection - we must obey the peer. * * The wording in RFC2462 is confusing, and there are * multiple description text for deprecated address * handling - worse, they are not exactly the same. * I believe 5.5.4 is the best one, so we follow 5.5.4. */ if (isipv6 && !V_ip6_use_deprecated) { struct in6_ifaddr *ia6; ia6 = in6ifa_ifwithaddr(&ip6->ip6_dst, 0 /* XXX */, false); if (ia6 != NULL && (ia6->ia6_flags & IN6_IFF_DEPRECATED)) { if ((s = tcp_log_addrs(&inc, th, NULL, NULL))) log(LOG_DEBUG, "%s; %s: Listen socket: " "Connection attempt to deprecated " "IPv6 address rejected\n", s, __func__); rstreason = BANDLIM_RST_OPENPORT; goto dropwithreset; } } #endif /* INET6 */ /* * Basic sanity checks on incoming SYN requests: * Don't respond if the destination is a link layer * broadcast according to RFC1122 4.2.3.10, p. 104. * If it is from this socket it must be forged. * Don't respond if the source or destination is a * global or subnet broad- or multicast address. * Note that it is quite possible to receive unicast * link-layer packets with a broadcast IP address. Use * in_broadcast() to find them. */ if (m->m_flags & (M_BCAST|M_MCAST)) { if ((s = tcp_log_addrs(&inc, th, NULL, NULL))) log(LOG_DEBUG, "%s; %s: Listen socket: " "Connection attempt from broad- or multicast " "link layer address ignored\n", s, __func__); goto dropunlock; } #ifdef INET6 if (isipv6) { if (th->th_dport == th->th_sport && IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &ip6->ip6_src)) { if ((s = tcp_log_addrs(&inc, th, NULL, NULL))) log(LOG_DEBUG, "%s; %s: Listen socket: " "Connection attempt to/from self " "ignored\n", s, __func__); goto dropunlock; } if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) { if ((s = tcp_log_addrs(&inc, th, NULL, NULL))) log(LOG_DEBUG, "%s; %s: Listen socket: " "Connection attempt from/to multicast " "address ignored\n", s, __func__); goto dropunlock; } } #endif #if defined(INET) && defined(INET6) else #endif #ifdef INET { if (th->th_dport == th->th_sport && ip->ip_dst.s_addr == ip->ip_src.s_addr) { if ((s = tcp_log_addrs(&inc, th, NULL, NULL))) log(LOG_DEBUG, "%s; %s: Listen socket: " "Connection attempt from/to self " "ignored\n", s, __func__); goto dropunlock; } if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) || IN_MULTICAST(ntohl(ip->ip_src.s_addr)) || ip->ip_src.s_addr == htonl(INADDR_BROADCAST) || in_broadcast(ip->ip_dst, m->m_pkthdr.rcvif)) { if ((s = tcp_log_addrs(&inc, th, NULL, NULL))) log(LOG_DEBUG, "%s; %s: Listen socket: " "Connection attempt from/to broad- " "or multicast address ignored\n", s, __func__); goto dropunlock; } } #endif /* * SYN appears to be valid. Create compressed TCP state * for syncache. */ TCP_PROBE3(debug__input, tp, th, m); tcp_dooptions(&to, optp, optlen, TO_SYN); if ((so = syncache_add(&inc, &to, th, inp, so, m, NULL, NULL, iptos, port)) != NULL) goto tfo_socket_result; /* * Entry added to syncache and mbuf consumed. * Only the listen socket is unlocked by syncache_add(). */ return (IPPROTO_DONE); } else if (tp->t_state == TCPS_LISTEN) { /* * When a listen socket is torn down the SO_ACCEPTCONN * flag is removed first while connections are drained * from the accept queue in a unlock/lock cycle of the * ACCEPT_LOCK, opening a race condition allowing a SYN * attempt go through unhandled. */ goto dropunlock; } #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) if (tp->t_flags & TF_SIGNATURE) { tcp_dooptions(&to, optp, optlen, thflags); if ((to.to_flags & TOF_SIGNATURE) == 0) { TCPSTAT_INC(tcps_sig_err_nosigopt); goto dropunlock; } if (!TCPMD5_ENABLED() || TCPMD5_INPUT(m, th, to.to_signature) != 0) goto dropunlock; } #endif TCP_PROBE5(receive, NULL, tp, m, tp, th); /* * Segment belongs to a connection in SYN_SENT, ESTABLISHED or later * state. tcp_do_segment() always consumes the mbuf chain, unlocks * the inpcb, and unlocks pcbinfo. * * XXXGL: in case of a pure SYN arriving on existing connection * TCP stacks won't need to modify the PCB, they would either drop * the segment silently, or send a challenge ACK. However, we try * to upgrade the lock, because calling convention for stacks is * write-lock on PCB. If upgrade fails, drop the SYN. */ if ((lookupflag & INPLOOKUP_RLOCKPCB) && INP_TRY_UPGRADE(inp) == 0) goto dropunlock; tp->t_fb->tfb_tcp_do_segment(tp, m, th, drop_hdrlen, tlen, iptos); return (IPPROTO_DONE); dropwithreset: /* * When blackholing do not respond with a RST but * completely ignore the segment and drop it. */ if (((rstreason == BANDLIM_RST_OPENPORT && V_blackhole == 3) || (rstreason == BANDLIM_RST_CLOSEDPORT && ((V_blackhole == 1 && (thflags & TH_SYN)) || V_blackhole > 1))) && (V_blackhole_local || ( #ifdef INET6 isipv6 ? !in6_localaddr(&ip6->ip6_src) : #endif #ifdef INET !in_localip(ip->ip_src) #else true #endif ))) goto dropunlock; TCP_PROBE5(receive, NULL, tp, m, tp, th); tcp_dropwithreset(m, th, tp, tlen, rstreason); m = NULL; /* mbuf chain got consumed. */ dropunlock: if (m != NULL) TCP_PROBE5(receive, NULL, tp, m, tp, th); if (inp != NULL) INP_UNLOCK(inp); drop: if (s != NULL) free(s, M_TCPLOG); if (m != NULL) m_freem(m); return (IPPROTO_DONE); } /* * Automatic sizing of receive socket buffer. Often the send * buffer size is not optimally adjusted to the actual network * conditions at hand (delay bandwidth product). Setting the * buffer size too small limits throughput on links with high * bandwidth and high delay (eg. trans-continental/oceanic links). * * On the receive side the socket buffer memory is only rarely * used to any significant extent. This allows us to be much * more aggressive in scaling the receive socket buffer. For * the case that the buffer space is actually used to a large * extent and we run out of kernel memory we can simply drop * the new segments; TCP on the sender will just retransmit it * later. Setting the buffer size too big may only consume too * much kernel memory if the application doesn't read() from * the socket or packet loss or reordering makes use of the * reassembly queue. * * The criteria to step up the receive buffer one notch are: * 1. Application has not set receive buffer size with * SO_RCVBUF. Setting SO_RCVBUF clears SB_AUTOSIZE. * 2. the number of bytes received during 1/2 of an sRTT * is at least 3/8 of the current socket buffer size. * 3. receive buffer size has not hit maximal automatic size; * * If all of the criteria are met we increaset the socket buffer * by a 1/2 (bounded by the max). This allows us to keep ahead * of slow-start but also makes it so our peer never gets limited * by our rwnd which we then open up causing a burst. * * This algorithm does two steps per RTT at most and only if * we receive a bulk stream w/o packet losses or reorderings. * Shrinking the buffer during idle times is not necessary as * it doesn't consume any memory when idle. * * TODO: Only step up if the application is actually serving * the buffer to better manage the socket buffer resources. */ int tcp_autorcvbuf(struct mbuf *m, struct tcphdr *th, struct socket *so, struct tcpcb *tp, int tlen) { int newsize = 0; if (V_tcp_do_autorcvbuf && (so->so_rcv.sb_flags & SB_AUTOSIZE) && tp->t_srtt != 0 && tp->rfbuf_ts != 0 && TCP_TS_TO_TICKS(tcp_ts_getticks() - tp->rfbuf_ts) > ((tp->t_srtt >> TCP_RTT_SHIFT)/2)) { if (tp->rfbuf_cnt > ((so->so_rcv.sb_hiwat / 2)/ 4 * 3) && so->so_rcv.sb_hiwat < V_tcp_autorcvbuf_max) { newsize = min((so->so_rcv.sb_hiwat + (so->so_rcv.sb_hiwat/2)), V_tcp_autorcvbuf_max); } TCP_PROBE6(receive__autoresize, NULL, tp, m, tp, th, newsize); /* Start over with next RTT. */ tp->rfbuf_ts = 0; tp->rfbuf_cnt = 0; } else { tp->rfbuf_cnt += tlen; /* add up */ } return (newsize); } int tcp_input(struct mbuf **mp, int *offp, int proto) { return(tcp_input_with_port(mp, offp, proto, 0)); } static void tcp_handle_wakeup(struct tcpcb *tp) { INP_WLOCK_ASSERT(tptoinpcb(tp)); if (tp->t_flags & TF_WAKESOR) { struct socket *so = tptosocket(tp); tp->t_flags &= ~TF_WAKESOR; - SOCKBUF_LOCK_ASSERT(&so->so_rcv); + SOCK_RECVBUF_LOCK_ASSERT(so); sorwakeup_locked(so); } } void tcp_do_segment(struct tcpcb *tp, struct mbuf *m, struct tcphdr *th, int drop_hdrlen, int tlen, uint8_t iptos) { uint16_t thflags; int acked, ourfinisacked, needoutput = 0; sackstatus_t sack_changed; int rstreason, todrop, win, incforsyn = 0; uint32_t tiwin; uint16_t nsegs; char *s; struct inpcb *inp = tptoinpcb(tp); struct socket *so = tptosocket(tp); struct in_conninfo *inc = &inp->inp_inc; struct mbuf *mfree; struct tcpopt to; int tfo_syn; u_int maxseg = 0; thflags = tcp_get_flags(th); tp->sackhint.last_sack_ack = 0; sack_changed = SACK_NOCHANGE; nsegs = max(1, m->m_pkthdr.lro_nsegs); NET_EPOCH_ASSERT(); INP_WLOCK_ASSERT(inp); KASSERT(tp->t_state > TCPS_LISTEN, ("%s: TCPS_LISTEN", __func__)); KASSERT(tp->t_state != TCPS_TIME_WAIT, ("%s: TCPS_TIME_WAIT", __func__)); #ifdef TCPPCAP /* Save segment, if requested. */ tcp_pcap_add(th, m, &(tp->t_inpkts)); #endif TCP_LOG_EVENT(tp, th, &so->so_rcv, &so->so_snd, TCP_LOG_IN, 0, tlen, NULL, true); if ((thflags & TH_SYN) && (thflags & TH_FIN) && V_drop_synfin) { if ((s = tcp_log_addrs(inc, th, NULL, NULL))) { log(LOG_DEBUG, "%s; %s: " "SYN|FIN segment ignored (based on " "sysctl setting)\n", s, __func__); free(s, M_TCPLOG); } goto drop; } /* * If a segment with the ACK-bit set arrives in the SYN-SENT state * check SEQ.ACK first. */ if ((tp->t_state == TCPS_SYN_SENT) && (thflags & TH_ACK) && (SEQ_LEQ(th->th_ack, tp->iss) || SEQ_GT(th->th_ack, tp->snd_max))) { rstreason = BANDLIM_UNLIMITED; tcp_log_end_status(tp, TCP_EI_STATUS_RST_IN_FRONT); goto dropwithreset; } /* * Segment received on connection. * Reset idle time and keep-alive timer. * XXX: This should be done after segment * validation to ignore broken/spoofed segs. */ if (tp->t_idle_reduce && (tp->snd_max == tp->snd_una) && ((ticks - tp->t_rcvtime) >= tp->t_rxtcur)) cc_after_idle(tp); tp->t_rcvtime = ticks; if (thflags & TH_FIN) tcp_log_end_status(tp, TCP_EI_STATUS_CLIENT_FIN); /* * Scale up the window into a 32-bit value. * For the SYN_SENT state the scale is zero. */ tiwin = th->th_win << tp->snd_scale; #ifdef STATS stats_voi_update_abs_ulong(tp->t_stats, VOI_TCP_FRWIN, tiwin); #endif /* * TCP ECN processing. */ if (tcp_ecn_input_segment(tp, thflags, tlen, tcp_packets_this_ack(tp, th->th_ack), iptos)) cc_cong_signal(tp, th, CC_ECN); /* * Parse options on any incoming segment. */ tcp_dooptions(&to, (u_char *)(th + 1), (th->th_off << 2) - sizeof(struct tcphdr), (thflags & TH_SYN) ? TO_SYN : 0); if (tp->t_flags2 & TF2_PROC_SACK_PROHIBIT) { /* * We don't look at sack's from the * peer because the MSS is too small which * can subject us to an attack. */ to.to_flags &= ~TOF_SACK; } #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) if ((tp->t_flags & TF_SIGNATURE) != 0 && (to.to_flags & TOF_SIGNATURE) == 0) { TCPSTAT_INC(tcps_sig_err_sigopt); /* XXX: should drop? */ } #endif /* * If echoed timestamp is later than the current time, * fall back to non RFC1323 RTT calculation. Normalize * timestamp if syncookies were used when this connection * was established. */ if ((to.to_flags & TOF_TS) && (to.to_tsecr != 0)) { to.to_tsecr -= tp->ts_offset; if (TSTMP_GT(to.to_tsecr, tcp_ts_getticks())) { to.to_tsecr = 0; } else if (tp->t_rxtshift == 1 && tp->t_flags & TF_PREVVALID && tp->t_badrxtwin != 0 && TSTMP_LT(to.to_tsecr, tp->t_badrxtwin)) { cc_cong_signal(tp, th, CC_RTO_ERR); } } /* * Process options only when we get SYN/ACK back. The SYN case * for incoming connections is handled in tcp_syncache. * According to RFC1323 the window field in a SYN (i.e., a * or ) segment itself is never scaled. * XXX this is traditional behavior, may need to be cleaned up. */ if (tp->t_state == TCPS_SYN_SENT && (thflags & TH_SYN)) { /* Handle parallel SYN for ECN */ tcp_ecn_input_parallel_syn(tp, thflags, iptos); if ((to.to_flags & TOF_SCALE) && (tp->t_flags & TF_REQ_SCALE) && !(tp->t_flags & TF_NOOPT)) { tp->t_flags |= TF_RCVD_SCALE; tp->snd_scale = to.to_wscale; } else { tp->t_flags &= ~TF_REQ_SCALE; } /* * Initial send window. It will be updated with * the next incoming segment to the scaled value. */ tp->snd_wnd = th->th_win; if ((to.to_flags & TOF_TS) && (tp->t_flags & TF_REQ_TSTMP) && !(tp->t_flags & TF_NOOPT)) { tp->t_flags |= TF_RCVD_TSTMP; tp->ts_recent = to.to_tsval; tp->ts_recent_age = tcp_ts_getticks(); } else { tp->t_flags &= ~TF_REQ_TSTMP; } if (to.to_flags & TOF_MSS) { tcp_mss(tp, to.to_mss); } if ((tp->t_flags & TF_SACK_PERMIT) && (!(to.to_flags & TOF_SACKPERM) || (tp->t_flags & TF_NOOPT))) { tp->t_flags &= ~TF_SACK_PERMIT; } if (tp->t_flags & TF_FASTOPEN) { if ((to.to_flags & TOF_FASTOPEN) && !(tp->t_flags & TF_NOOPT)) { uint16_t mss; if (to.to_flags & TOF_MSS) { mss = to.to_mss; } else { if ((inp->inp_vflag & INP_IPV6) != 0) { mss = TCP6_MSS; } else { mss = TCP_MSS; } } tcp_fastopen_update_cache(tp, mss, to.to_tfo_len, to.to_tfo_cookie); } else { tcp_fastopen_disable_path(tp); } } } /* * If timestamps were negotiated during SYN/ACK and a * segment without a timestamp is received, silently drop * the segment, unless it is a RST segment or missing timestamps are * tolerated. * See section 3.2 of RFC 7323. */ if ((tp->t_flags & TF_RCVD_TSTMP) && !(to.to_flags & TOF_TS)) { if (((thflags & TH_RST) != 0) || V_tcp_tolerate_missing_ts) { if ((s = tcp_log_addrs(inc, th, NULL, NULL))) { log(LOG_DEBUG, "%s; %s: Timestamp missing, " "segment processed normally\n", s, __func__); free(s, M_TCPLOG); } } else { if ((s = tcp_log_addrs(inc, th, NULL, NULL))) { log(LOG_DEBUG, "%s; %s: Timestamp missing, " "segment silently dropped\n", s, __func__); free(s, M_TCPLOG); } goto drop; } } /* * If timestamps were not negotiated during SYN/ACK and a * segment with a timestamp is received, ignore the * timestamp and process the packet normally. * See section 3.2 of RFC 7323. */ if (!(tp->t_flags & TF_RCVD_TSTMP) && (to.to_flags & TOF_TS)) { if ((s = tcp_log_addrs(inc, th, NULL, NULL))) { log(LOG_DEBUG, "%s; %s: Timestamp not expected, " "segment processed normally\n", s, __func__); free(s, M_TCPLOG); } } /* * Header prediction: check for the two common cases * of a uni-directional data xfer. If the packet has * no control flags, is in-sequence, the window didn't * change and we're not retransmitting, it's a * candidate. If the length is zero and the ack moved * forward, we're the sender side of the xfer. Just * free the data acked & wake any higher level process * that was blocked waiting for space. If the length * is non-zero and the ack didn't move, we're the * receiver side. If we're getting packets in-order * (the reassembly queue is empty), add the data to * the socket buffer and note that we need a delayed ack. * Make sure that the hidden state-flags are also off. * Since we check for TCPS_ESTABLISHED first, it can only * be TH_NEEDSYN. */ if (tp->t_state == TCPS_ESTABLISHED && th->th_seq == tp->rcv_nxt && (thflags & (TH_SYN|TH_FIN|TH_RST|TH_URG|TH_ACK)) == TH_ACK && tp->snd_nxt == tp->snd_max && tiwin && tiwin == tp->snd_wnd && ((tp->t_flags & (TF_NEEDSYN|TF_NEEDFIN)) == 0) && SEGQ_EMPTY(tp) && ((to.to_flags & TOF_TS) == 0 || TSTMP_GEQ(to.to_tsval, tp->ts_recent)) ) { /* * If last ACK falls within this segment's sequence numbers, * record the timestamp. * NOTE that the test is modified according to the latest * proposal of the tcplw@cray.com list (Braden 1993/04/26). */ if ((to.to_flags & TOF_TS) != 0 && SEQ_LEQ(th->th_seq, tp->last_ack_sent)) { tp->ts_recent_age = tcp_ts_getticks(); tp->ts_recent = to.to_tsval; } if (tlen == 0) { if (SEQ_GT(th->th_ack, tp->snd_una) && SEQ_LEQ(th->th_ack, tp->snd_max) && !IN_RECOVERY(tp->t_flags) && (to.to_flags & TOF_SACK) == 0 && TAILQ_EMPTY(&tp->snd_holes)) { /* * This is a pure ack for outstanding data. */ TCPSTAT_INC(tcps_predack); /* * "bad retransmit" recovery without timestamps. */ if ((to.to_flags & TOF_TS) == 0 && tp->t_rxtshift == 1 && tp->t_flags & TF_PREVVALID && tp->t_badrxtwin != 0 && TSTMP_LT(ticks, tp->t_badrxtwin)) { cc_cong_signal(tp, th, CC_RTO_ERR); } /* * Recalculate the transmit timer / rtt. * * Some boxes send broken timestamp replies * during the SYN+ACK phase, ignore * timestamps of 0 or we could calculate a * huge RTT and blow up the retransmit timer. */ if ((to.to_flags & TOF_TS) != 0 && to.to_tsecr) { uint32_t t; t = tcp_ts_getticks() - to.to_tsecr; if (!tp->t_rttlow || tp->t_rttlow > t) tp->t_rttlow = t; tcp_xmit_timer(tp, TCP_TS_TO_TICKS(t) + 1); } else if (tp->t_rtttime && SEQ_GT(th->th_ack, tp->t_rtseq)) { if (!tp->t_rttlow || tp->t_rttlow > ticks - tp->t_rtttime) tp->t_rttlow = ticks - tp->t_rtttime; tcp_xmit_timer(tp, ticks - tp->t_rtttime); } acked = BYTES_THIS_ACK(tp, th); #ifdef TCP_HHOOK /* Run HHOOK_TCP_ESTABLISHED_IN helper hooks. */ hhook_run_tcp_est_in(tp, th, &to); #endif TCPSTAT_ADD(tcps_rcvackpack, nsegs); TCPSTAT_ADD(tcps_rcvackbyte, acked); sbdrop(&so->so_snd, acked); if (SEQ_GT(tp->snd_una, tp->snd_recover) && SEQ_LEQ(th->th_ack, tp->snd_recover)) tp->snd_recover = th->th_ack - 1; /* * Let the congestion control algorithm update * congestion control related information. This * typically means increasing the congestion * window. */ cc_ack_received(tp, th, nsegs, CC_ACK); tp->snd_una = th->th_ack; /* * Pull snd_wl2 up to prevent seq wrap relative * to th_ack. */ tp->snd_wl2 = th->th_ack; tp->t_dupacks = 0; m_freem(m); /* * If all outstanding data are acked, stop * retransmit timer, otherwise restart timer * using current (possibly backed-off) value. * If process is waiting for space, * wakeup/selwakeup/signal. If data * are ready to send, let tcp_output * decide between more output or persist. */ TCP_PROBE3(debug__input, tp, th, m); /* * Clear t_acktime if remote side has ACKd * all data in the socket buffer. * Otherwise, update t_acktime if we received * a sufficiently large ACK. */ if (sbavail(&so->so_snd) == 0) tp->t_acktime = 0; else if (acked > 1) tp->t_acktime = ticks; if (tp->snd_una == tp->snd_max) tcp_timer_activate(tp, TT_REXMT, 0); else if (!tcp_timer_active(tp, TT_PERSIST)) tcp_timer_activate(tp, TT_REXMT, TP_RXTCUR(tp)); sowwakeup(so); /* * Only call tcp_output when there * is new data available to be sent * or we need to send an ACK. */ if ((tp->t_flags & TF_ACKNOW) || (sbavail(&so->so_snd) >= SEQ_SUB(tp->snd_max, tp->snd_una))) { (void) tcp_output(tp); } goto check_delack; } } else if (th->th_ack == tp->snd_una && tlen <= sbspace(&so->so_rcv)) { int newsize = 0; /* automatic sockbuf scaling */ /* * This is a pure, in-sequence data packet with * nothing on the reassembly queue and we have enough * buffer space to take it. */ /* Clean receiver SACK report if present */ if ((tp->t_flags & TF_SACK_PERMIT) && tp->rcv_numsacks) tcp_clean_sackreport(tp); TCPSTAT_INC(tcps_preddat); tp->rcv_nxt += tlen; if (tlen && ((tp->t_flags2 & TF2_FBYTES_COMPLETE) == 0) && (tp->t_fbyte_in == 0)) { tp->t_fbyte_in = ticks; if (tp->t_fbyte_in == 0) tp->t_fbyte_in = 1; if (tp->t_fbyte_out && tp->t_fbyte_in) tp->t_flags2 |= TF2_FBYTES_COMPLETE; } /* * Pull snd_wl1 up to prevent seq wrap relative to * th_seq. */ tp->snd_wl1 = th->th_seq; /* * Pull rcv_up up to prevent seq wrap relative to * rcv_nxt. */ tp->rcv_up = tp->rcv_nxt; TCPSTAT_ADD(tcps_rcvpack, nsegs); TCPSTAT_ADD(tcps_rcvbyte, tlen); TCP_PROBE3(debug__input, tp, th, m); newsize = tcp_autorcvbuf(m, th, so, tp, tlen); /* Add data to socket buffer. */ - SOCKBUF_LOCK(&so->so_rcv); + SOCK_RECVBUF_LOCK(so); if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { m_freem(m); } else { /* * Set new socket buffer size. * Give up when limit is reached. */ if (newsize) if (!sbreserve_locked(so, SO_RCV, newsize, NULL)) so->so_rcv.sb_flags &= ~SB_AUTOSIZE; m_adj(m, drop_hdrlen); /* delayed header drop */ sbappendstream_locked(&so->so_rcv, m, 0); } /* NB: sorwakeup_locked() does an implicit unlock. */ sorwakeup_locked(so); if (DELAY_ACK(tp, tlen)) { tp->t_flags |= TF_DELACK; } else { tp->t_flags |= TF_ACKNOW; (void) tcp_output(tp); } goto check_delack; } } /* * Calculate amount of space in receive window, * and then do TCP input processing. * Receive window is amount of space in rcv queue, * but not less than advertised window. */ win = sbspace(&so->so_rcv); if (win < 0) win = 0; tp->rcv_wnd = imax(win, (int)(tp->rcv_adv - tp->rcv_nxt)); switch (tp->t_state) { /* * If the state is SYN_RECEIVED: * if seg contains an ACK, but not for our SYN/ACK, send a RST. */ case TCPS_SYN_RECEIVED: if (thflags & TH_RST) { /* Handle RST segments later. */ break; } if ((thflags & TH_ACK) && (SEQ_LEQ(th->th_ack, tp->snd_una) || SEQ_GT(th->th_ack, tp->snd_max))) { rstreason = BANDLIM_RST_OPENPORT; tcp_log_end_status(tp, TCP_EI_STATUS_RST_IN_FRONT); goto dropwithreset; } if (tp->t_flags & TF_FASTOPEN) { /* * When a TFO connection is in SYN_RECEIVED, the * only valid packets are the initial SYN, a * retransmit/copy of the initial SYN (possibly with * a subset of the original data), a valid ACK, a * FIN, or a RST. */ if ((thflags & (TH_SYN|TH_ACK)) == (TH_SYN|TH_ACK)) { rstreason = BANDLIM_RST_OPENPORT; tcp_log_end_status(tp, TCP_EI_STATUS_RST_IN_FRONT); goto dropwithreset; } else if (thflags & TH_SYN) { /* non-initial SYN is ignored */ if ((tcp_timer_active(tp, TT_DELACK) || tcp_timer_active(tp, TT_REXMT))) goto drop; } else if (!(thflags & (TH_ACK|TH_FIN|TH_RST))) { goto drop; } } break; /* * If the state is SYN_SENT: * if seg contains a RST with valid ACK (SEQ.ACK has already * been verified), then drop the connection. * if seg contains a RST without an ACK, drop the seg. * if seg does not contain SYN, then drop the seg. * Otherwise this is an acceptable SYN segment * initialize tp->rcv_nxt and tp->irs * if seg contains ack then advance tp->snd_una * if seg contains an ECE and ECN support is enabled, the stream * is ECN capable. * if SYN has been acked change to ESTABLISHED else SYN_RCVD state * arrange for segment to be acked (eventually) * continue processing rest of data/controls, beginning with URG */ case TCPS_SYN_SENT: if ((thflags & (TH_ACK|TH_RST)) == (TH_ACK|TH_RST)) { TCP_PROBE5(connect__refused, NULL, tp, m, tp, th); tcp_log_end_status(tp, TCP_EI_STATUS_RST_IN_FRONT); tp = tcp_drop(tp, ECONNREFUSED); } if (thflags & TH_RST) goto drop; if (!(thflags & TH_SYN)) goto drop; tp->irs = th->th_seq; tcp_rcvseqinit(tp); if (thflags & TH_ACK) { int tfo_partial_ack = 0; TCPSTAT_INC(tcps_connects); soisconnected(so); #ifdef MAC mac_socketpeer_set_from_mbuf(m, so); #endif /* Do window scaling on this connection? */ if ((tp->t_flags & (TF_RCVD_SCALE|TF_REQ_SCALE)) == (TF_RCVD_SCALE|TF_REQ_SCALE)) { tp->rcv_scale = tp->request_r_scale; } tp->rcv_adv += min(tp->rcv_wnd, TCP_MAXWIN << tp->rcv_scale); tp->snd_una++; /* SYN is acked */ if (SEQ_LT(tp->snd_nxt, tp->snd_una)) tp->snd_nxt = tp->snd_una; /* * If not all the data that was sent in the TFO SYN * has been acked, resend the remainder right away. */ if ((tp->t_flags & TF_FASTOPEN) && (tp->snd_una != tp->snd_max)) { tp->snd_nxt = th->th_ack; tfo_partial_ack = 1; } /* * If there's data, delay ACK; if there's also a FIN * ACKNOW will be turned on later. */ if (DELAY_ACK(tp, tlen) && tlen != 0 && !tfo_partial_ack) tcp_timer_activate(tp, TT_DELACK, tcp_delacktime); else tp->t_flags |= TF_ACKNOW; tcp_ecn_input_syn_sent(tp, thflags, iptos); /* * Received in SYN_SENT[*] state. * Transitions: * SYN_SENT --> ESTABLISHED * SYN_SENT* --> FIN_WAIT_1 */ tp->t_starttime = ticks; if (tp->t_flags & TF_NEEDFIN) { tp->t_acktime = ticks; tcp_state_change(tp, TCPS_FIN_WAIT_1); tp->t_flags &= ~TF_NEEDFIN; thflags &= ~TH_SYN; } else { tcp_state_change(tp, TCPS_ESTABLISHED); TCP_PROBE5(connect__established, NULL, tp, m, tp, th); cc_conn_init(tp); tcp_timer_activate(tp, TT_KEEP, TP_KEEPIDLE(tp)); } } else { /* * Received initial SYN in SYN-SENT[*] state => * simultaneous open. * If it succeeds, connection is * half-synchronized. * Otherwise, do 3-way handshake: * SYN-SENT -> SYN-RECEIVED * SYN-SENT* -> SYN-RECEIVED* */ tp->t_flags |= (TF_ACKNOW | TF_NEEDSYN | TF_SONOTCONN); tcp_timer_activate(tp, TT_REXMT, 0); tcp_state_change(tp, TCPS_SYN_RECEIVED); } /* * Advance th->th_seq to correspond to first data byte. * If data, trim to stay within window, * dropping FIN if necessary. */ th->th_seq++; if (tlen > tp->rcv_wnd) { todrop = tlen - tp->rcv_wnd; m_adj(m, -todrop); tlen = tp->rcv_wnd; thflags &= ~TH_FIN; TCPSTAT_INC(tcps_rcvpackafterwin); TCPSTAT_ADD(tcps_rcvbyteafterwin, todrop); } tp->snd_wl1 = th->th_seq - 1; tp->rcv_up = th->th_seq; /* * Client side of transaction: already sent SYN and data. * If the remote host used T/TCP to validate the SYN, * our data will be ACK'd; if so, enter normal data segment * processing in the middle of step 5, ack processing. * Otherwise, goto step 6. */ if (thflags & TH_ACK) goto process_ACK; goto step6; } /* * States other than LISTEN or SYN_SENT. * First check the RST flag and sequence number since reset segments * are exempt from the timestamp and connection count tests. This * fixes a bug introduced by the Stevens, vol. 2, p. 960 bugfix * below which allowed reset segments in half the sequence space * to fall though and be processed (which gives forged reset * segments with a random sequence number a 50 percent chance of * killing a connection). * Then check timestamp, if present. * Then check the connection count, if present. * Then check that at least some bytes of segment are within * receive window. If segment begins before rcv_nxt, * drop leading data (and SYN); if nothing left, just ack. */ if (thflags & TH_RST) { /* * RFC5961 Section 3.2 * * - RST drops connection only if SEG.SEQ == RCV.NXT. * - If RST is in window, we send challenge ACK. * * Note: to take into account delayed ACKs, we should * test against last_ack_sent instead of rcv_nxt. * Note 2: we handle special case of closed window, not * covered by the RFC. */ if ((SEQ_GEQ(th->th_seq, tp->last_ack_sent) && SEQ_LT(th->th_seq, tp->last_ack_sent + tp->rcv_wnd)) || (tp->rcv_wnd == 0 && tp->last_ack_sent == th->th_seq)) { KASSERT(tp->t_state != TCPS_SYN_SENT, ("%s: TH_RST for TCPS_SYN_SENT th %p tp %p", __func__, th, tp)); if (V_tcp_insecure_rst || tp->last_ack_sent == th->th_seq) { TCPSTAT_INC(tcps_drops); /* Drop the connection. */ switch (tp->t_state) { case TCPS_SYN_RECEIVED: so->so_error = ECONNREFUSED; goto close; case TCPS_ESTABLISHED: case TCPS_FIN_WAIT_1: case TCPS_FIN_WAIT_2: case TCPS_CLOSE_WAIT: case TCPS_CLOSING: case TCPS_LAST_ACK: so->so_error = ECONNRESET; close: /* FALLTHROUGH */ default: tcp_log_end_status(tp, TCP_EI_STATUS_CLIENT_RST); tp = tcp_close(tp); } } else { TCPSTAT_INC(tcps_badrst); tcp_send_challenge_ack(tp, th, m); m = NULL; } } goto drop; } /* * RFC5961 Section 4.2 * Send challenge ACK for any SYN in synchronized state. */ if ((thflags & TH_SYN) && tp->t_state != TCPS_SYN_SENT && tp->t_state != TCPS_SYN_RECEIVED) { TCPSTAT_INC(tcps_badsyn); if (V_tcp_insecure_syn && SEQ_GEQ(th->th_seq, tp->last_ack_sent) && SEQ_LT(th->th_seq, tp->last_ack_sent + tp->rcv_wnd)) { tcp_log_end_status(tp, TCP_EI_STATUS_RST_IN_FRONT); tp = tcp_drop(tp, ECONNRESET); rstreason = BANDLIM_UNLIMITED; } else { tcp_ecn_input_syn_sent(tp, thflags, iptos); tcp_send_challenge_ack(tp, th, m); m = NULL; } goto drop; } /* * RFC 1323 PAWS: If we have a timestamp reply on this segment * and it's less than ts_recent, drop it. */ if ((to.to_flags & TOF_TS) != 0 && tp->ts_recent && TSTMP_LT(to.to_tsval, tp->ts_recent)) { /* Check to see if ts_recent is over 24 days old. */ if (tcp_ts_getticks() - tp->ts_recent_age > TCP_PAWS_IDLE) { /* * Invalidate ts_recent. If this segment updates * ts_recent, the age will be reset later and ts_recent * will get a valid value. If it does not, setting * ts_recent to zero will at least satisfy the * requirement that zero be placed in the timestamp * echo reply when ts_recent isn't valid. The * age isn't reset until we get a valid ts_recent * because we don't want out-of-order segments to be * dropped when ts_recent is old. */ tp->ts_recent = 0; } else { TCPSTAT_INC(tcps_rcvduppack); TCPSTAT_ADD(tcps_rcvdupbyte, tlen); TCPSTAT_INC(tcps_pawsdrop); if (tlen) goto dropafterack; goto drop; } } /* * In the SYN-RECEIVED state, validate that the packet belongs to * this connection before trimming the data to fit the receive * window. Check the sequence number versus IRS since we know * the sequence numbers haven't wrapped. This is a partial fix * for the "LAND" DoS attack. */ if (tp->t_state == TCPS_SYN_RECEIVED && SEQ_LT(th->th_seq, tp->irs)) { rstreason = BANDLIM_RST_OPENPORT; tcp_log_end_status(tp, TCP_EI_STATUS_RST_IN_FRONT); goto dropwithreset; } todrop = tp->rcv_nxt - th->th_seq; if (todrop > 0) { if (thflags & TH_SYN) { thflags &= ~TH_SYN; th->th_seq++; if (th->th_urp > 1) th->th_urp--; else thflags &= ~TH_URG; todrop--; } /* * Following if statement from Stevens, vol. 2, p. 960. */ if (todrop > tlen || (todrop == tlen && (thflags & TH_FIN) == 0)) { /* * Any valid FIN must be to the left of the window. * At this point the FIN must be a duplicate or out * of sequence; drop it. */ thflags &= ~TH_FIN; /* * Send an ACK to resynchronize and drop any data. * But keep on processing for RST or ACK. */ tp->t_flags |= TF_ACKNOW; todrop = tlen; TCPSTAT_INC(tcps_rcvduppack); TCPSTAT_ADD(tcps_rcvdupbyte, todrop); } else { TCPSTAT_INC(tcps_rcvpartduppack); TCPSTAT_ADD(tcps_rcvpartdupbyte, todrop); } /* * DSACK - add SACK block for dropped range */ if ((todrop > 0) && (tp->t_flags & TF_SACK_PERMIT)) { tcp_update_sack_list(tp, th->th_seq, th->th_seq + todrop); /* * ACK now, as the next in-sequence segment * will clear the DSACK block again */ tp->t_flags |= TF_ACKNOW; } drop_hdrlen += todrop; /* drop from the top afterwards */ th->th_seq += todrop; tlen -= todrop; if (th->th_urp > todrop) th->th_urp -= todrop; else { thflags &= ~TH_URG; th->th_urp = 0; } } /* * If new data are received on a connection after the * user processes are gone, then RST the other end if * no FIN has been processed. */ if ((tp->t_flags & TF_CLOSED) && tlen > 0 && TCPS_HAVERCVDFIN(tp->t_state) == 0) { if ((s = tcp_log_addrs(inc, th, NULL, NULL))) { log(LOG_DEBUG, "%s; %s: %s: Received %d bytes of data " "after socket was closed, " "sending RST and removing tcpcb\n", s, __func__, tcpstates[tp->t_state], tlen); free(s, M_TCPLOG); } tcp_log_end_status(tp, TCP_EI_STATUS_DATA_A_CLOSE); /* tcp_close will kill the inp pre-log the Reset */ tcp_log_end_status(tp, TCP_EI_STATUS_SERVER_RST); tp = tcp_close(tp); TCPSTAT_INC(tcps_rcvafterclose); rstreason = BANDLIM_UNLIMITED; goto dropwithreset; } /* * If segment ends after window, drop trailing data * (and PUSH and FIN); if nothing left, just ACK. */ todrop = (th->th_seq + tlen) - (tp->rcv_nxt + tp->rcv_wnd); if (todrop > 0) { TCPSTAT_INC(tcps_rcvpackafterwin); if (todrop >= tlen) { TCPSTAT_ADD(tcps_rcvbyteafterwin, tlen); /* * If window is closed can only take segments at * window edge, and have to drop data and PUSH from * incoming segments. Continue processing, but * remember to ack. Otherwise, drop segment * and ack. */ if (tp->rcv_wnd == 0 && th->th_seq == tp->rcv_nxt) { tp->t_flags |= TF_ACKNOW; TCPSTAT_INC(tcps_rcvwinprobe); } else goto dropafterack; } else TCPSTAT_ADD(tcps_rcvbyteafterwin, todrop); m_adj(m, -todrop); tlen -= todrop; thflags &= ~(TH_PUSH|TH_FIN); } /* * If last ACK falls within this segment's sequence numbers, * record its timestamp. * NOTE: * 1) That the test incorporates suggestions from the latest * proposal of the tcplw@cray.com list (Braden 1993/04/26). * 2) That updating only on newer timestamps interferes with * our earlier PAWS tests, so this check should be solely * predicated on the sequence space of this segment. * 3) That we modify the segment boundary check to be * Last.ACK.Sent <= SEG.SEQ + SEG.Len * instead of RFC1323's * Last.ACK.Sent < SEG.SEQ + SEG.Len, * This modified check allows us to overcome RFC1323's * limitations as described in Stevens TCP/IP Illustrated * Vol. 2 p.869. In such cases, we can still calculate the * RTT correctly when RCV.NXT == Last.ACK.Sent. */ if ((to.to_flags & TOF_TS) != 0 && SEQ_LEQ(th->th_seq, tp->last_ack_sent) && SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen + ((thflags & (TH_SYN|TH_FIN)) != 0))) { tp->ts_recent_age = tcp_ts_getticks(); tp->ts_recent = to.to_tsval; } /* * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN * flag is on (half-synchronized state), then queue data for * later processing; else drop segment and return. */ if ((thflags & TH_ACK) == 0) { if (tp->t_state == TCPS_SYN_RECEIVED || (tp->t_flags & TF_NEEDSYN)) { if (tp->t_state == TCPS_SYN_RECEIVED && (tp->t_flags & TF_FASTOPEN)) { tp->snd_wnd = tiwin; cc_conn_init(tp); } goto step6; } else if (tp->t_flags & TF_ACKNOW) goto dropafterack; else goto drop; } /* * Ack processing. */ if (SEQ_GEQ(tp->snd_una, tp->iss + (TCP_MAXWIN << tp->snd_scale))) { /* Checking SEG.ACK against ISS is definitely redundant. */ tp->t_flags2 |= TF2_NO_ISS_CHECK; } if (!V_tcp_insecure_ack) { tcp_seq seq_min; bool ghost_ack_check; if (tp->t_flags2 & TF2_NO_ISS_CHECK) { /* Check for too old ACKs (RFC 5961, Section 5.2). */ seq_min = tp->snd_una - tp->max_sndwnd; ghost_ack_check = false; } else { if (SEQ_GT(tp->iss + 1, tp->snd_una - tp->max_sndwnd)) { /* Checking for ghost ACKs is stricter. */ seq_min = tp->iss + 1; ghost_ack_check = true; } else { /* * Checking for too old ACKs (RFC 5961, * Section 5.2) is stricter. */ seq_min = tp->snd_una - tp->max_sndwnd; ghost_ack_check = false; } } if (SEQ_LT(th->th_ack, seq_min)) { if (ghost_ack_check) TCPSTAT_INC(tcps_rcvghostack); else TCPSTAT_INC(tcps_rcvacktooold); tcp_send_challenge_ack(tp, th, m); m = NULL; goto drop; } } switch (tp->t_state) { /* * In SYN_RECEIVED state, the ack ACKs our SYN, so enter * ESTABLISHED state and continue processing. * The ACK was checked above. */ case TCPS_SYN_RECEIVED: TCPSTAT_INC(tcps_connects); if (tp->t_flags & TF_SONOTCONN) { /* * Usually SYN_RECEIVED had been created from a LISTEN, * and solisten_enqueue() has already marked the socket * layer as connected. If it didn't, which can happen * only with an accept_filter(9), then the tp is marked * with TF_SONOTCONN. The other reason for this mark * to be set is a simultaneous open, a SYN_RECEIVED * that had been created from SYN_SENT. */ tp->t_flags &= ~TF_SONOTCONN; soisconnected(so); } /* Do window scaling? */ if ((tp->t_flags & (TF_RCVD_SCALE|TF_REQ_SCALE)) == (TF_RCVD_SCALE|TF_REQ_SCALE)) { tp->rcv_scale = tp->request_r_scale; } tp->snd_wnd = tiwin; /* * Make transitions: * SYN-RECEIVED -> ESTABLISHED * SYN-RECEIVED* -> FIN-WAIT-1 */ tp->t_starttime = ticks; if ((tp->t_flags & TF_FASTOPEN) && tp->t_tfo_pending) { tcp_fastopen_decrement_counter(tp->t_tfo_pending); tp->t_tfo_pending = NULL; } if (tp->t_flags & TF_NEEDFIN) { tp->t_acktime = ticks; tcp_state_change(tp, TCPS_FIN_WAIT_1); tp->t_flags &= ~TF_NEEDFIN; } else { tcp_state_change(tp, TCPS_ESTABLISHED); TCP_PROBE5(accept__established, NULL, tp, m, tp, th); /* * TFO connections call cc_conn_init() during SYN * processing. Calling it again here for such * connections is not harmless as it would undo the * snd_cwnd reduction that occurs when a TFO SYN|ACK * is retransmitted. */ if (!(tp->t_flags & TF_FASTOPEN)) cc_conn_init(tp); tcp_timer_activate(tp, TT_KEEP, TP_KEEPIDLE(tp)); } /* * Account for the ACK of our SYN prior to * regular ACK processing below, except for * simultaneous SYN, which is handled later. */ if (SEQ_GT(th->th_ack, tp->snd_una) && !(tp->t_flags & TF_NEEDSYN)) incforsyn = 1; /* * If segment contains data or ACK, will call tcp_reass() * later; if not, do so now to pass queued data to user. */ if (tlen == 0 && (thflags & TH_FIN) == 0) { (void) tcp_reass(tp, (struct tcphdr *)0, NULL, 0, (struct mbuf *)0); tcp_handle_wakeup(tp); } tp->snd_wl1 = th->th_seq - 1; /* FALLTHROUGH */ /* * In ESTABLISHED state: drop duplicate ACKs; ACK out of range * ACKs. If the ack is in the range * tp->snd_una < th->th_ack <= tp->snd_max * then advance tp->snd_una to th->th_ack and drop * data from the retransmission queue. If this ACK reflects * more up to date window information we update our window information. */ case TCPS_ESTABLISHED: case TCPS_FIN_WAIT_1: case TCPS_FIN_WAIT_2: case TCPS_CLOSE_WAIT: case TCPS_CLOSING: case TCPS_LAST_ACK: if (SEQ_GT(th->th_ack, tp->snd_max)) { TCPSTAT_INC(tcps_rcvacktoomuch); goto dropafterack; } if (tcp_is_sack_recovery(tp, &to)) { sack_changed = tcp_sack_doack(tp, &to, th->th_ack); if ((sack_changed != SACK_NOCHANGE) && (tp->t_flags & TF_LRD)) { tcp_sack_lost_retransmission(tp, th); } } else /* * Reset the value so that previous (valid) value * from the last ack with SACK doesn't get used. */ tp->sackhint.sacked_bytes = 0; #ifdef TCP_HHOOK /* Run HHOOK_TCP_ESTABLISHED_IN helper hooks. */ hhook_run_tcp_est_in(tp, th, &to); #endif if (SEQ_LEQ(th->th_ack, tp->snd_una)) { maxseg = tcp_maxseg(tp); if (tlen == 0 && (tiwin == tp->snd_wnd || (tp->t_flags & TF_SACK_PERMIT))) { /* * If this is the first time we've seen a * FIN from the remote, this is not a * duplicate and it needs to be processed * normally. This happens during a * simultaneous close. */ if ((thflags & TH_FIN) && (TCPS_HAVERCVDFIN(tp->t_state) == 0)) { tp->t_dupacks = 0; break; } TCPSTAT_INC(tcps_rcvdupack); /* * If we have outstanding data (other than * a window probe), this is a completely * duplicate ack (ie, window info didn't * change and FIN isn't set), * the ack is the biggest we've * seen and we've seen exactly our rexmt * threshold of them, assume a packet * has been dropped and retransmit it. * Kludge snd_nxt & the congestion * window so we send only this one * packet. * * We know we're losing at the current * window size so do congestion avoidance * (set ssthresh to half the current window * and pull our congestion window back to * the new ssthresh). * * Dup acks mean that packets have left the * network (they're now cached at the receiver) * so bump cwnd by the amount in the receiver * to keep a constant cwnd packets in the * network. * * When using TCP ECN, notify the peer that * we reduced the cwnd. */ /* * Following 2 kinds of acks should not affect * dupack counting: * 1) Old acks * 2) Acks with SACK but without any new SACK * information in them. These could result from * any anomaly in the network like a switch * duplicating packets or a possible DoS attack. */ if (th->th_ack != tp->snd_una || (tcp_is_sack_recovery(tp, &to) && (sack_changed == SACK_NOCHANGE))) { break; } else if (!tcp_timer_active(tp, TT_REXMT)) { tp->t_dupacks = 0; } else if (++tp->t_dupacks > tcprexmtthresh || IN_FASTRECOVERY(tp->t_flags)) { cc_ack_received(tp, th, nsegs, CC_DUPACK); if (V_tcp_do_prr && IN_FASTRECOVERY(tp->t_flags) && (tp->t_flags & TF_SACK_PERMIT)) { tcp_do_prr_ack(tp, th, &to, sack_changed, &maxseg); } else if (tcp_is_sack_recovery(tp, &to) && IN_FASTRECOVERY(tp->t_flags) && (tp->snd_nxt == tp->snd_max)) { int awnd; /* * Compute the amount of data in flight first. * We can inject new data into the pipe iff * we have less than ssthresh * worth of data in flight. */ if (V_tcp_do_newsack) { awnd = tcp_compute_pipe(tp); } else { awnd = (tp->snd_nxt - tp->snd_fack) + tp->sackhint.sack_bytes_rexmit; } if (awnd < tp->snd_ssthresh) { tp->snd_cwnd += imax(maxseg, imin(2 * maxseg, tp->sackhint.delivered_data)); if (tp->snd_cwnd > tp->snd_ssthresh) tp->snd_cwnd = tp->snd_ssthresh; } } else if (tcp_is_sack_recovery(tp, &to) && IN_FASTRECOVERY(tp->t_flags) && SEQ_LT(tp->snd_nxt, tp->snd_max)) { tp->snd_cwnd += imax(maxseg, imin(2 * maxseg, tp->sackhint.delivered_data)); } else { tp->snd_cwnd += maxseg; } (void) tcp_output(tp); goto drop; } else if (tp->t_dupacks == tcprexmtthresh || (tp->t_flags & TF_SACK_PERMIT && V_tcp_do_newsack && tp->sackhint.sacked_bytes > (tcprexmtthresh - 1) * maxseg)) { enter_recovery: /* * Above is the RFC6675 trigger condition of * more than (dupthresh-1)*maxseg sacked data. * If the count of holes in the * scoreboard is >= dupthresh, we could * also enter loss recovery, but don't * have that value readily available. */ tp->t_dupacks = tcprexmtthresh; tcp_seq onxt = tp->snd_nxt; /* * If we're doing sack, check to * see if we're already in sack * recovery. If we're not doing sack, * check to see if we're in newreno * recovery. */ if (tcp_is_sack_recovery(tp, &to)) { if (IN_FASTRECOVERY(tp->t_flags)) { tp->t_dupacks = 0; break; } } else { if (SEQ_LEQ(th->th_ack, tp->snd_recover)) { tp->t_dupacks = 0; break; } } /* Congestion signal before ack. */ cc_cong_signal(tp, th, CC_NDUPACK); cc_ack_received(tp, th, nsegs, CC_DUPACK); tcp_timer_activate(tp, TT_REXMT, 0); tp->t_rtttime = 0; if (V_tcp_do_prr) { /* * snd_ssthresh and snd_recover are * already updated by cc_cong_signal. */ if (tcp_is_sack_recovery(tp, &to)) { /* * Include Limited Transmit * segments here */ tp->sackhint.prr_delivered = imin(tp->snd_max - th->th_ack, (tp->snd_limited + 1) * maxseg); } else { tp->sackhint.prr_delivered = maxseg; } tp->sackhint.recover_fs = max(1, tp->snd_nxt - tp->snd_una); } tp->snd_limited = 0; if (tcp_is_sack_recovery(tp, &to)) { TCPSTAT_INC(tcps_sack_recovery_episode); /* * When entering LR after RTO due to * Duplicate ACKs, retransmit existing * holes from the scoreboard. */ tcp_resend_sackholes(tp); /* Avoid inflating cwnd in tcp_output */ tp->snd_nxt = tp->snd_max; tp->snd_cwnd = tcp_compute_pipe(tp) + maxseg; (void) tcp_output(tp); /* Set cwnd to the expected flightsize */ tp->snd_cwnd = tp->snd_ssthresh; if (SEQ_GT(th->th_ack, tp->snd_una)) { goto resume_partialack; } goto drop; } tp->snd_nxt = th->th_ack; tp->snd_cwnd = maxseg; (void) tcp_output(tp); KASSERT(tp->snd_limited <= 2, ("%s: tp->snd_limited too big", __func__)); tp->snd_cwnd = tp->snd_ssthresh + maxseg * (tp->t_dupacks - tp->snd_limited); if (SEQ_GT(onxt, tp->snd_nxt)) tp->snd_nxt = onxt; goto drop; } else if (V_tcp_do_rfc3042) { /* * Process first and second duplicate * ACKs. Each indicates a segment * leaving the network, creating room * for more. Make sure we can send a * packet on reception of each duplicate * ACK by increasing snd_cwnd by one * segment. Restore the original * snd_cwnd after packet transmission. */ cc_ack_received(tp, th, nsegs, CC_DUPACK); uint32_t oldcwnd = tp->snd_cwnd; tcp_seq oldsndmax = tp->snd_max; u_int sent; int avail; KASSERT(tp->t_dupacks == 1 || tp->t_dupacks == 2, ("%s: dupacks not 1 or 2", __func__)); if (tp->t_dupacks == 1) tp->snd_limited = 0; if ((tp->snd_nxt == tp->snd_max) && (tp->t_rxtshift == 0)) tp->snd_cwnd = SEQ_SUB(tp->snd_nxt, tp->snd_una) - tcp_sack_adjust(tp); tp->snd_cwnd += (tp->t_dupacks - tp->snd_limited) * maxseg; /* * Only call tcp_output when there * is new data available to be sent * or we need to send an ACK. */ - SOCKBUF_LOCK(&so->so_snd); + SOCK_SENDBUF_LOCK(so); avail = sbavail(&so->so_snd); - SOCKBUF_UNLOCK(&so->so_snd); + SOCK_SENDBUF_UNLOCK(so); if (tp->t_flags & TF_ACKNOW || (avail >= SEQ_SUB(tp->snd_nxt, tp->snd_una))) { (void) tcp_output(tp); } sent = SEQ_SUB(tp->snd_max, oldsndmax); if (sent > maxseg) { KASSERT((tp->t_dupacks == 2 && tp->snd_limited == 0) || (sent == maxseg + 1 && tp->t_flags & TF_SENTFIN), ("%s: sent too much", __func__)); tp->snd_limited = 2; } else if (sent > 0) { ++tp->snd_limited; } tp->snd_cwnd = oldcwnd; goto drop; } } break; } else { /* * This ack is advancing the left edge, reset the * counter. */ tp->t_dupacks = 0; /* * If this ack also has new SACK info, increment the * counter as per rfc6675. The variable * sack_changed tracks all changes to the SACK * scoreboard, including when partial ACKs without * SACK options are received, and clear the scoreboard * from the left side. Such partial ACKs should not be * counted as dupacks here. */ if (tcp_is_sack_recovery(tp, &to) && (((tp->t_rxtshift == 0) && (sack_changed != SACK_NOCHANGE)) || ((tp->t_rxtshift > 0) && (sack_changed == SACK_NEWLOSS))) && (tp->snd_nxt == tp->snd_max)) { tp->t_dupacks++; /* limit overhead by setting maxseg last */ if (!IN_FASTRECOVERY(tp->t_flags) && (tp->sackhint.sacked_bytes > ((tcprexmtthresh - 1) * (maxseg = tcp_maxseg(tp))))) { goto enter_recovery; } } } resume_partialack: KASSERT(SEQ_GT(th->th_ack, tp->snd_una), ("%s: th_ack <= snd_una", __func__)); /* * If the congestion window was inflated to account * for the other side's cached packets, retract it. */ if (SEQ_LT(th->th_ack, tp->snd_recover)) { if (IN_FASTRECOVERY(tp->t_flags)) { if (tp->t_flags & TF_SACK_PERMIT) { if (V_tcp_do_prr && (to.to_flags & TOF_SACK)) { tcp_timer_activate(tp, TT_REXMT, 0); tp->t_rtttime = 0; tcp_do_prr_ack(tp, th, &to, sack_changed, &maxseg); tp->t_flags |= TF_ACKNOW; (void) tcp_output(tp); } else { tcp_sack_partialack(tp, th, &maxseg); } } else { tcp_newreno_partial_ack(tp, th); } } else if (IN_CONGRECOVERY(tp->t_flags) && (V_tcp_do_prr)) { tp->sackhint.delivered_data = BYTES_THIS_ACK(tp, th); tp->snd_fack = th->th_ack; /* * During ECN cwnd reduction * always use PRR-SSRB */ tcp_do_prr_ack(tp, th, &to, SACK_CHANGE, &maxseg); (void) tcp_output(tp); } } /* * If we reach this point, ACK is not a duplicate, * i.e., it ACKs something we sent. */ if (tp->t_flags & TF_NEEDSYN) { /* * T/TCP: Connection was half-synchronized, and our * SYN has been ACK'd (so connection is now fully * synchronized). Go to non-starred state, * increment snd_una for ACK of SYN, and check if * we can do window scaling. */ tp->t_flags &= ~TF_NEEDSYN; tp->snd_una++; /* Do window scaling? */ if ((tp->t_flags & (TF_RCVD_SCALE|TF_REQ_SCALE)) == (TF_RCVD_SCALE|TF_REQ_SCALE)) { tp->rcv_scale = tp->request_r_scale; /* Send window already scaled. */ } } process_ACK: INP_WLOCK_ASSERT(inp); /* * Adjust for the SYN bit in sequence space, * but don't account for it in cwnd calculations. * This is for the SYN_RECEIVED, non-simultaneous * SYN case. SYN_SENT and simultaneous SYN are * treated elsewhere. */ if (incforsyn) tp->snd_una++; acked = BYTES_THIS_ACK(tp, th); KASSERT(acked >= 0, ("%s: acked unexepectedly negative " "(tp->snd_una=%u, th->th_ack=%u, tp=%p, m=%p)", __func__, tp->snd_una, th->th_ack, tp, m)); TCPSTAT_ADD(tcps_rcvackpack, nsegs); TCPSTAT_ADD(tcps_rcvackbyte, acked); /* * If we just performed our first retransmit, and the ACK * arrives within our recovery window, then it was a mistake * to do the retransmit in the first place. Recover our * original cwnd and ssthresh, and proceed to transmit where * we left off. */ if (tp->t_rxtshift == 1 && tp->t_flags & TF_PREVVALID && tp->t_badrxtwin != 0 && to.to_flags & TOF_TS && to.to_tsecr != 0 && TSTMP_LT(to.to_tsecr, tp->t_badrxtwin)) cc_cong_signal(tp, th, CC_RTO_ERR); /* * If we have a timestamp reply, update smoothed * round trip time. If no timestamp is present but * transmit timer is running and timed sequence * number was acked, update smoothed round trip time. * Since we now have an rtt measurement, cancel the * timer backoff (cf., Phil Karn's retransmit alg.). * Recompute the initial retransmit timer. * * Some boxes send broken timestamp replies * during the SYN+ACK phase, ignore * timestamps of 0 or we could calculate a * huge RTT and blow up the retransmit timer. */ if ((to.to_flags & TOF_TS) != 0 && to.to_tsecr) { uint32_t t; t = tcp_ts_getticks() - to.to_tsecr; if (!tp->t_rttlow || tp->t_rttlow > t) tp->t_rttlow = t; tcp_xmit_timer(tp, TCP_TS_TO_TICKS(t) + 1); } else if (tp->t_rtttime && SEQ_GT(th->th_ack, tp->t_rtseq)) { if (!tp->t_rttlow || tp->t_rttlow > ticks - tp->t_rtttime) tp->t_rttlow = ticks - tp->t_rtttime; tcp_xmit_timer(tp, ticks - tp->t_rtttime); } - SOCKBUF_LOCK(&so->so_snd); + SOCK_SENDBUF_LOCK(so); /* * Clear t_acktime if remote side has ACKd all data in the * socket buffer and FIN (if applicable). * Otherwise, update t_acktime if we received a sufficiently * large ACK. */ if ((tp->t_state <= TCPS_CLOSE_WAIT && acked == sbavail(&so->so_snd)) || acked > sbavail(&so->so_snd)) tp->t_acktime = 0; else if (acked > 1) tp->t_acktime = ticks; /* * If all outstanding data is acked, stop retransmit * timer and remember to restart (more output or persist). * If there is more data to be acked, restart retransmit * timer, using current (possibly backed-off) value. */ if (th->th_ack == tp->snd_max) { tcp_timer_activate(tp, TT_REXMT, 0); needoutput = 1; } else if (!tcp_timer_active(tp, TT_PERSIST)) tcp_timer_activate(tp, TT_REXMT, TP_RXTCUR(tp)); /* * If no data (only SYN) was ACK'd, * skip rest of ACK processing. */ if (acked == 0) { - SOCKBUF_UNLOCK(&so->so_snd); + SOCK_SENDBUF_UNLOCK(so); goto step6; } /* * Let the congestion control algorithm update congestion * control related information. This typically means increasing * the congestion window. */ cc_ack_received(tp, th, nsegs, CC_ACK); if (acked > sbavail(&so->so_snd)) { if (tp->snd_wnd >= sbavail(&so->so_snd)) tp->snd_wnd -= sbavail(&so->so_snd); else tp->snd_wnd = 0; mfree = sbcut_locked(&so->so_snd, (int)sbavail(&so->so_snd)); ourfinisacked = 1; } else { mfree = sbcut_locked(&so->so_snd, acked); if (tp->snd_wnd >= (uint32_t) acked) tp->snd_wnd -= acked; else tp->snd_wnd = 0; ourfinisacked = 0; } /* NB: sowwakeup_locked() does an implicit unlock. */ sowwakeup_locked(so); m_freem(mfree); /* Detect una wraparound. */ if (!IN_RECOVERY(tp->t_flags) && SEQ_GT(tp->snd_una, tp->snd_recover) && SEQ_LEQ(th->th_ack, tp->snd_recover)) tp->snd_recover = th->th_ack - 1; tp->snd_una = th->th_ack; if (IN_RECOVERY(tp->t_flags) && SEQ_GEQ(th->th_ack, tp->snd_recover)) { cc_post_recovery(tp, th); } if (SEQ_GT(tp->snd_una, tp->snd_recover)) { tp->snd_recover = tp->snd_una; } if (SEQ_LT(tp->snd_nxt, tp->snd_una)) tp->snd_nxt = tp->snd_una; switch (tp->t_state) { /* * In FIN_WAIT_1 STATE in addition to the processing * for the ESTABLISHED state if our FIN is now acknowledged * then enter FIN_WAIT_2. */ case TCPS_FIN_WAIT_1: if (ourfinisacked) { /* * If we can't receive any more * data, then closing user can proceed. * Starting the timer is contrary to the * specification, but if we don't get a FIN * we'll hang forever. */ if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { tcp_free_sackholes(tp); soisdisconnected(so); tcp_timer_activate(tp, TT_2MSL, (tcp_fast_finwait2_recycle ? tcp_finwait2_timeout : TP_MAXIDLE(tp))); } tcp_state_change(tp, TCPS_FIN_WAIT_2); } break; /* * In CLOSING STATE in addition to the processing for * the ESTABLISHED state if the ACK acknowledges our FIN * then enter the TIME-WAIT state, otherwise ignore * the segment. */ case TCPS_CLOSING: if (ourfinisacked) { tcp_twstart(tp); m_freem(m); return; } break; /* * In LAST_ACK, we may still be waiting for data to drain * and/or to be acked, as well as for the ack of our FIN. * If our FIN is now acknowledged, delete the TCB, * enter the closed state and return. */ case TCPS_LAST_ACK: if (ourfinisacked) { tp = tcp_close(tp); goto drop; } break; } } step6: INP_WLOCK_ASSERT(inp); /* * Update window information. * Don't look at window if no ACK: TAC's send garbage on first SYN. */ if ((thflags & TH_ACK) && (SEQ_LT(tp->snd_wl1, th->th_seq) || (tp->snd_wl1 == th->th_seq && (SEQ_LT(tp->snd_wl2, th->th_ack) || (tp->snd_wl2 == th->th_ack && tiwin > tp->snd_wnd))))) { /* keep track of pure window updates */ if (tlen == 0 && tp->snd_wl2 == th->th_ack && tiwin > tp->snd_wnd) TCPSTAT_INC(tcps_rcvwinupd); tp->snd_wnd = tiwin; tp->snd_wl1 = th->th_seq; tp->snd_wl2 = th->th_ack; if (tp->snd_wnd > tp->max_sndwnd) tp->max_sndwnd = tp->snd_wnd; needoutput = 1; } /* * Process segments with URG. */ if ((thflags & TH_URG) && th->th_urp && TCPS_HAVERCVDFIN(tp->t_state) == 0) { /* * This is a kludge, but if we receive and accept * random urgent pointers, we'll crash in * soreceive. It's hard to imagine someone * actually wanting to send this much urgent data. */ - SOCKBUF_LOCK(&so->so_rcv); + SOCK_RECVBUF_LOCK(so); if (th->th_urp + sbavail(&so->so_rcv) > sb_max) { th->th_urp = 0; /* XXX */ thflags &= ~TH_URG; /* XXX */ - SOCKBUF_UNLOCK(&so->so_rcv); /* XXX */ + SOCK_RECVBUF_UNLOCK(so); /* XXX */ goto dodata; /* XXX */ } /* * If this segment advances the known urgent pointer, * then mark the data stream. This should not happen * in CLOSE_WAIT, CLOSING, LAST_ACK or TIME_WAIT STATES since * a FIN has been received from the remote side. * In these states we ignore the URG. * * According to RFC961 (Assigned Protocols), * the urgent pointer points to the last octet * of urgent data. We continue, however, * to consider it to indicate the first octet * of data past the urgent section as the original * spec states (in one of two places). */ if (SEQ_GT(th->th_seq+th->th_urp, tp->rcv_up)) { tp->rcv_up = th->th_seq + th->th_urp; so->so_oobmark = sbavail(&so->so_rcv) + (tp->rcv_up - tp->rcv_nxt) - 1; if (so->so_oobmark == 0) so->so_rcv.sb_state |= SBS_RCVATMARK; sohasoutofband(so); tp->t_oobflags &= ~(TCPOOB_HAVEDATA | TCPOOB_HADDATA); } - SOCKBUF_UNLOCK(&so->so_rcv); + SOCK_RECVBUF_UNLOCK(so); /* * Remove out of band data so doesn't get presented to user. * This can happen independent of advancing the URG pointer, * but if two URG's are pending at once, some out-of-band * data may creep in... ick. */ if (th->th_urp <= (uint32_t)tlen && !(so->so_options & SO_OOBINLINE)) { /* hdr drop is delayed */ tcp_pulloutofband(so, th, m, drop_hdrlen); } } else { /* * If no out of band data is expected, * pull receive urgent pointer along * with the receive window. */ if (SEQ_GT(tp->rcv_nxt, tp->rcv_up)) tp->rcv_up = tp->rcv_nxt; } dodata: /* XXX */ INP_WLOCK_ASSERT(inp); /* * Process the segment text, merging it into the TCP sequencing queue, * and arranging for acknowledgment of receipt if necessary. * This process logically involves adjusting tp->rcv_wnd as data * is presented to the user (this happens in tcp_usrreq.c, * case PRU_RCVD). If a FIN has already been received on this * connection then we just ignore the text. */ tfo_syn = ((tp->t_state == TCPS_SYN_RECEIVED) && (tp->t_flags & TF_FASTOPEN)); if ((tlen || (thflags & TH_FIN) || (tfo_syn && tlen > 0)) && TCPS_HAVERCVDFIN(tp->t_state) == 0) { tcp_seq save_start = th->th_seq; tcp_seq save_rnxt = tp->rcv_nxt; int save_tlen = tlen; m_adj(m, drop_hdrlen); /* delayed header drop */ /* * Insert segment which includes th into TCP reassembly queue * with control block tp. Set thflags to whether reassembly now * includes a segment with FIN. This handles the common case * inline (segment is the next to be received on an established * connection, and the queue is empty), avoiding linkage into * and removal from the queue and repetition of various * conversions. * Set DELACK for segments received in order, but ack * immediately when segments are out of order (so * fast retransmit can work). */ if (th->th_seq == tp->rcv_nxt && SEGQ_EMPTY(tp) && (TCPS_HAVEESTABLISHED(tp->t_state) || tfo_syn)) { if (DELAY_ACK(tp, tlen) || tfo_syn) tp->t_flags |= TF_DELACK; else tp->t_flags |= TF_ACKNOW; tp->rcv_nxt += tlen; if (tlen && ((tp->t_flags2 & TF2_FBYTES_COMPLETE) == 0) && (tp->t_fbyte_in == 0)) { tp->t_fbyte_in = ticks; if (tp->t_fbyte_in == 0) tp->t_fbyte_in = 1; if (tp->t_fbyte_out && tp->t_fbyte_in) tp->t_flags2 |= TF2_FBYTES_COMPLETE; } thflags = tcp_get_flags(th) & TH_FIN; TCPSTAT_INC(tcps_rcvpack); TCPSTAT_ADD(tcps_rcvbyte, tlen); - SOCKBUF_LOCK(&so->so_rcv); + SOCK_RECVBUF_LOCK(so); if (so->so_rcv.sb_state & SBS_CANTRCVMORE) m_freem(m); else sbappendstream_locked(&so->so_rcv, m, 0); tp->t_flags |= TF_WAKESOR; } else { /* * XXX: Due to the header drop above "th" is * theoretically invalid by now. Fortunately * m_adj() doesn't actually frees any mbufs * when trimming from the head. */ tcp_seq temp = save_start; thflags = tcp_reass(tp, th, &temp, &tlen, m); tp->t_flags |= TF_ACKNOW; } if ((tp->t_flags & TF_SACK_PERMIT) && (save_tlen > 0) && TCPS_HAVEESTABLISHED(tp->t_state)) { if ((tlen == 0) && (SEQ_LT(save_start, save_rnxt))) { /* * DSACK actually handled in the fastpath * above. */ tcp_update_sack_list(tp, save_start, save_start + save_tlen); } else if ((tlen > 0) && SEQ_GT(tp->rcv_nxt, save_rnxt)) { if ((tp->rcv_numsacks >= 1) && (tp->sackblks[0].end == save_start)) { /* * Partial overlap, recorded at todrop * above. */ tcp_update_sack_list(tp, tp->sackblks[0].start, tp->sackblks[0].end); } else { tcp_update_dsack_list(tp, save_start, save_start + save_tlen); } } else if (tlen >= save_tlen) { /* Update of sackblks. */ tcp_update_dsack_list(tp, save_start, save_start + save_tlen); } else if (tlen > 0) { tcp_update_dsack_list(tp, save_start, save_start + tlen); } } tcp_handle_wakeup(tp); #if 0 /* * Note the amount of data that peer has sent into * our window, in order to estimate the sender's * buffer size. * XXX: Unused. */ if (SEQ_GT(tp->rcv_adv, tp->rcv_nxt)) len = so->so_rcv.sb_hiwat - (tp->rcv_adv - tp->rcv_nxt); else len = so->so_rcv.sb_hiwat; #endif } else { if ((s = tcp_log_addrs(inc, th, NULL, NULL))) { if (tlen > 0) { if ((thflags & TH_FIN) != 0) { log(LOG_DEBUG, "%s; %s: %s: " "Received %d bytes of data and FIN " "after having received a FIN, " "just dropping both\n", s, __func__, tcpstates[tp->t_state], tlen); } else { log(LOG_DEBUG, "%s; %s: %s: " "Received %d bytes of data " "after having received a FIN, " "just dropping it\n", s, __func__, tcpstates[tp->t_state], tlen); } } else { if ((thflags & TH_FIN) != 0) { log(LOG_DEBUG, "%s; %s: %s: " "Received FIN " "after having received a FIN, " "just dropping it\n", s, __func__, tcpstates[tp->t_state]); } } free(s, M_TCPLOG); } m_freem(m); thflags &= ~TH_FIN; } /* * If FIN is received ACK the FIN and let the user know * that the connection is closing. */ if (thflags & TH_FIN) { if (TCPS_HAVERCVDFIN(tp->t_state) == 0) { /* The socket upcall is handled by socantrcvmore. */ socantrcvmore(so); /* * If connection is half-synchronized * (ie NEEDSYN flag on) then delay ACK, * so it may be piggybacked when SYN is sent. * Otherwise, since we received a FIN then no * more input can be expected, send ACK now. */ if (tp->t_flags & TF_NEEDSYN) tp->t_flags |= TF_DELACK; else tp->t_flags |= TF_ACKNOW; tp->rcv_nxt++; } switch (tp->t_state) { /* * In SYN_RECEIVED and ESTABLISHED STATES * enter the CLOSE_WAIT state. */ case TCPS_SYN_RECEIVED: tp->t_starttime = ticks; /* FALLTHROUGH */ case TCPS_ESTABLISHED: tcp_state_change(tp, TCPS_CLOSE_WAIT); break; /* * If still in FIN_WAIT_1 STATE FIN has not been acked so * enter the CLOSING state. */ case TCPS_FIN_WAIT_1: tcp_state_change(tp, TCPS_CLOSING); break; /* * In FIN_WAIT_2 state enter the TIME_WAIT state, * starting the time-wait timer, turning off the other * standard timers. */ case TCPS_FIN_WAIT_2: tcp_twstart(tp); return; } } TCP_PROBE3(debug__input, tp, th, m); /* * Return any desired output. */ if (needoutput || (tp->t_flags & TF_ACKNOW)) { (void) tcp_output(tp); } check_delack: INP_WLOCK_ASSERT(inp); if (tp->t_flags & TF_DELACK) { tp->t_flags &= ~TF_DELACK; tcp_timer_activate(tp, TT_DELACK, tcp_delacktime); } INP_WUNLOCK(inp); return; dropafterack: /* * Generate an ACK dropping incoming segment if it occupies * sequence space, where the ACK reflects our state. * * We can now skip the test for the RST flag since all * paths to this code happen after packets containing * RST have been dropped. * * In the SYN-RECEIVED state, don't send an ACK unless the * segment we received passes the SYN-RECEIVED ACK test. * If it fails send a RST. This breaks the loop in the * "LAND" DoS attack, and also prevents an ACK storm * between two listening ports that have been sent forged * SYN segments, each with the source address of the other. */ if (tp->t_state == TCPS_SYN_RECEIVED && (thflags & TH_ACK) && (SEQ_GT(tp->snd_una, th->th_ack) || SEQ_GT(th->th_ack, tp->snd_max)) ) { rstreason = BANDLIM_RST_OPENPORT; tcp_log_end_status(tp, TCP_EI_STATUS_RST_IN_FRONT); goto dropwithreset; } TCP_PROBE3(debug__input, tp, th, m); tp->t_flags |= TF_ACKNOW; (void) tcp_output(tp); INP_WUNLOCK(inp); m_freem(m); return; dropwithreset: if (tp != NULL) { tcp_dropwithreset(m, th, tp, tlen, rstreason); INP_WUNLOCK(inp); } else tcp_dropwithreset(m, th, NULL, tlen, rstreason); return; drop: /* * Drop space held by incoming segment and return. */ TCP_PROBE3(debug__input, tp, th, m); if (tp != NULL) { INP_WUNLOCK(inp); } m_freem(m); } /* * Issue RST and make ACK acceptable to originator of segment. * The mbuf must still include the original packet header. * tp may be NULL. */ void tcp_dropwithreset(struct mbuf *m, struct tcphdr *th, struct tcpcb *tp, int tlen, int rstreason) { #ifdef INET struct ip *ip; #endif #ifdef INET6 struct ip6_hdr *ip6; #endif if (tp != NULL) { INP_LOCK_ASSERT(tptoinpcb(tp)); } /* Don't bother if destination was broadcast/multicast. */ if ((tcp_get_flags(th) & TH_RST) || m->m_flags & (M_BCAST|M_MCAST)) goto drop; #ifdef INET6 if (mtod(m, struct ip *)->ip_v == 6) { ip6 = mtod(m, struct ip6_hdr *); if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) goto drop; /* IPv6 anycast check is done at tcp6_input() */ } #endif #if defined(INET) && defined(INET6) else #endif #ifdef INET { ip = mtod(m, struct ip *); if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) || IN_MULTICAST(ntohl(ip->ip_src.s_addr)) || ip->ip_src.s_addr == htonl(INADDR_BROADCAST) || in_broadcast(ip->ip_dst, m->m_pkthdr.rcvif)) goto drop; } #endif /* Perform bandwidth limiting. */ if (badport_bandlim(rstreason) < 0) goto drop; /* tcp_respond consumes the mbuf chain. */ if (tcp_get_flags(th) & TH_ACK) { tcp_respond(tp, mtod(m, void *), th, m, (tcp_seq)0, th->th_ack, TH_RST); } else { if (tcp_get_flags(th) & TH_SYN) tlen++; if (tcp_get_flags(th) & TH_FIN) tlen++; tcp_respond(tp, mtod(m, void *), th, m, th->th_seq+tlen, (tcp_seq)0, TH_RST|TH_ACK); } return; drop: m_freem(m); } /* * Parse TCP options and place in tcpopt. */ void tcp_dooptions(struct tcpopt *to, u_char *cp, int cnt, int flags) { int opt, optlen; to->to_flags = 0; for (; cnt > 0; cnt -= optlen, cp += optlen) { opt = cp[0]; if (opt == TCPOPT_EOL) break; if (opt == TCPOPT_NOP) optlen = 1; else { if (cnt < 2) break; optlen = cp[1]; if (optlen < 2 || optlen > cnt) break; } switch (opt) { case TCPOPT_MAXSEG: if (optlen != TCPOLEN_MAXSEG) continue; if (!(flags & TO_SYN)) continue; to->to_flags |= TOF_MSS; bcopy((char *)cp + 2, (char *)&to->to_mss, sizeof(to->to_mss)); to->to_mss = ntohs(to->to_mss); break; case TCPOPT_WINDOW: if (optlen != TCPOLEN_WINDOW) continue; if (!(flags & TO_SYN)) continue; to->to_flags |= TOF_SCALE; to->to_wscale = min(cp[2], TCP_MAX_WINSHIFT); break; case TCPOPT_TIMESTAMP: if (optlen != TCPOLEN_TIMESTAMP) continue; to->to_flags |= TOF_TS; bcopy((char *)cp + 2, (char *)&to->to_tsval, sizeof(to->to_tsval)); to->to_tsval = ntohl(to->to_tsval); bcopy((char *)cp + 6, (char *)&to->to_tsecr, sizeof(to->to_tsecr)); to->to_tsecr = ntohl(to->to_tsecr); break; case TCPOPT_SIGNATURE: /* * In order to reply to a host which has set the * TCP_SIGNATURE option in its initial SYN, we have * to record the fact that the option was observed * here for the syncache code to perform the correct * response. */ if (optlen != TCPOLEN_SIGNATURE) continue; to->to_flags |= TOF_SIGNATURE; to->to_signature = cp + 2; break; case TCPOPT_SACK_PERMITTED: if (optlen != TCPOLEN_SACK_PERMITTED) continue; if (!(flags & TO_SYN)) continue; if (!V_tcp_do_sack) continue; to->to_flags |= TOF_SACKPERM; break; case TCPOPT_SACK: if (optlen <= 2 || (optlen - 2) % TCPOLEN_SACK != 0) continue; if (flags & TO_SYN) continue; to->to_flags |= TOF_SACK; to->to_nsacks = (optlen - 2) / TCPOLEN_SACK; to->to_sacks = cp + 2; TCPSTAT_INC(tcps_sack_rcv_blocks); break; case TCPOPT_FAST_OPEN: /* * Cookie length validation is performed by the * server side cookie checking code or the client * side cookie cache update code. */ if (!(flags & TO_SYN)) continue; if (!V_tcp_fastopen_client_enable && !V_tcp_fastopen_server_enable) continue; to->to_flags |= TOF_FASTOPEN; to->to_tfo_len = optlen - 2; to->to_tfo_cookie = to->to_tfo_len ? cp + 2 : NULL; break; default: continue; } } } /* * Pull out of band byte out of a segment so * it doesn't appear in the user's data queue. * It is still reflected in the segment length for * sequencing purposes. */ void tcp_pulloutofband(struct socket *so, struct tcphdr *th, struct mbuf *m, int off) { int cnt = off + th->th_urp - 1; while (cnt >= 0) { if (m->m_len > cnt) { char *cp = mtod(m, caddr_t) + cnt; struct tcpcb *tp = sototcpcb(so); INP_WLOCK_ASSERT(tptoinpcb(tp)); tp->t_iobc = *cp; tp->t_oobflags |= TCPOOB_HAVEDATA; bcopy(cp+1, cp, (unsigned)(m->m_len - cnt - 1)); m->m_len--; if (m->m_flags & M_PKTHDR) m->m_pkthdr.len--; return; } cnt -= m->m_len; m = m->m_next; if (m == NULL) break; } panic("tcp_pulloutofband"); } /* * Collect new round-trip time estimate * and update averages and current timeout. */ void tcp_xmit_timer(struct tcpcb *tp, int rtt) { int delta; INP_WLOCK_ASSERT(tptoinpcb(tp)); TCPSTAT_INC(tcps_rttupdated); if (tp->t_rttupdated < UCHAR_MAX) tp->t_rttupdated++; #ifdef STATS stats_voi_update_abs_u32(tp->t_stats, VOI_TCP_RTT, imax(0, rtt * 1000 / hz)); #endif if ((tp->t_srtt != 0) && (tp->t_rxtshift <= TCP_RTT_INVALIDATE)) { /* * srtt is stored as fixed point with 5 bits after the * binary point (i.e., scaled by 8). The following magic * is equivalent to the smoothing algorithm in rfc793 with * an alpha of .875 (srtt = rtt/8 + srtt*7/8 in fixed * point). Adjust rtt to origin 0. */ delta = ((rtt - 1) << TCP_DELTA_SHIFT) - (tp->t_srtt >> (TCP_RTT_SHIFT - TCP_DELTA_SHIFT)); if ((tp->t_srtt += delta) <= 0) tp->t_srtt = 1; /* * We accumulate a smoothed rtt variance (actually, a * smoothed mean difference), then set the retransmit * timer to smoothed rtt + 4 times the smoothed variance. * rttvar is stored as fixed point with 4 bits after the * binary point (scaled by 16). The following is * equivalent to rfc793 smoothing with an alpha of .75 * (rttvar = rttvar*3/4 + |delta| / 4). This replaces * rfc793's wired-in beta. */ if (delta < 0) delta = -delta; delta -= tp->t_rttvar >> (TCP_RTTVAR_SHIFT - TCP_DELTA_SHIFT); if ((tp->t_rttvar += delta) <= 0) tp->t_rttvar = 1; } else { /* * No rtt measurement yet - use the unsmoothed rtt. * Set the variance to half the rtt (so our first * retransmit happens at 3*rtt). */ tp->t_srtt = rtt << TCP_RTT_SHIFT; tp->t_rttvar = rtt << (TCP_RTTVAR_SHIFT - 1); } tp->t_rtttime = 0; tp->t_rxtshift = 0; /* * the retransmit should happen at rtt + 4 * rttvar. * Because of the way we do the smoothing, srtt and rttvar * will each average +1/2 tick of bias. When we compute * the retransmit timer, we want 1/2 tick of rounding and * 1 extra tick because of +-1/2 tick uncertainty in the * firing of the timer. The bias will give us exactly the * 1.5 tick we need. But, because the bias is * statistical, we have to test that we don't drop below * the minimum feasible timer (which is 2 ticks). */ TCPT_RANGESET(tp->t_rxtcur, TCP_REXMTVAL(tp), max(tp->t_rttmin, rtt + 2), TCPTV_REXMTMAX); /* * We received an ack for a packet that wasn't retransmitted; * it is probably safe to discard any error indications we've * received recently. This isn't quite right, but close enough * for now (a route might have failed after we sent a segment, * and the return path might not be symmetrical). */ tp->t_softerror = 0; } /* * Determine a reasonable value for maxseg size. * If the route is known, check route for mtu. * If none, use an mss that can be handled on the outgoing interface * without forcing IP to fragment. If no route is found, route has no mtu, * or the destination isn't local, use a default, hopefully conservative * size (usually 512 or the default IP max size, but no more than the mtu * of the interface), as we can't discover anything about intervening * gateways or networks. We also initialize the congestion/slow start * window to be a single segment if the destination isn't local. * While looking at the routing entry, we also initialize other path-dependent * parameters from pre-set or cached values in the routing entry. * * NOTE that resulting t_maxseg doesn't include space for TCP options or * IP options, e.g. IPSEC data, since length of this data may vary, and * thus it is calculated for every segment separately in tcp_output(). * * NOTE that this routine is only called when we process an incoming * segment, or an ICMP need fragmentation datagram. Outgoing SYN/ACK MSS * settings are handled in tcp_mssopt(). */ void tcp_mss_update(struct tcpcb *tp, int offer, int mtuoffer, struct hc_metrics_lite *metricptr, struct tcp_ifcap *cap) { int mss = 0; uint32_t maxmtu = 0; struct inpcb *inp = tptoinpcb(tp); struct hc_metrics_lite metrics; #ifdef INET6 int isipv6 = ((inp->inp_vflag & INP_IPV6) != 0) ? 1 : 0; size_t min_protoh = isipv6 ? sizeof (struct ip6_hdr) + sizeof (struct tcphdr) : sizeof (struct tcpiphdr); #else size_t min_protoh = sizeof(struct tcpiphdr); #endif INP_WLOCK_ASSERT(inp); if (tp->t_port) min_protoh += V_tcp_udp_tunneling_overhead; if (mtuoffer != -1) { KASSERT(offer == -1, ("%s: conflict", __func__)); offer = mtuoffer - min_protoh; } /* Initialize. */ #ifdef INET6 if (isipv6) { maxmtu = tcp_maxmtu6(&inp->inp_inc, cap); tp->t_maxseg = V_tcp_v6mssdflt; } #endif #if defined(INET) && defined(INET6) else #endif #ifdef INET { maxmtu = tcp_maxmtu(&inp->inp_inc, cap); tp->t_maxseg = V_tcp_mssdflt; } #endif /* * No route to sender, stay with default mss and return. */ if (maxmtu == 0) { /* * In case we return early we need to initialize metrics * to a defined state as tcp_hc_get() would do for us * if there was no cache hit. */ if (metricptr != NULL) bzero(metricptr, sizeof(struct hc_metrics_lite)); return; } /* What have we got? */ switch (offer) { case 0: /* * Offer == 0 means that there was no MSS on the SYN * segment, in this case we use tcp_mssdflt as * already assigned to t_maxseg above. */ offer = tp->t_maxseg; break; case -1: /* * Offer == -1 means that we didn't receive SYN yet. */ /* FALLTHROUGH */ default: /* * Prevent DoS attack with too small MSS. Round up * to at least minmss. */ offer = max(offer, V_tcp_minmss); } /* * rmx information is now retrieved from tcp_hostcache. */ tcp_hc_get(&inp->inp_inc, &metrics); if (metricptr != NULL) bcopy(&metrics, metricptr, sizeof(struct hc_metrics_lite)); /* * If there's a discovered mtu in tcp hostcache, use it. * Else, use the link mtu. */ if (metrics.rmx_mtu) mss = min(metrics.rmx_mtu, maxmtu) - min_protoh; else { #ifdef INET6 if (isipv6) { mss = maxmtu - min_protoh; if (!V_path_mtu_discovery && !in6_localaddr(&inp->in6p_faddr)) mss = min(mss, V_tcp_v6mssdflt); } #endif #if defined(INET) && defined(INET6) else #endif #ifdef INET { mss = maxmtu - min_protoh; if (!V_path_mtu_discovery && !in_localaddr(inp->inp_faddr)) mss = min(mss, V_tcp_mssdflt); } #endif /* * XXX - The above conditional (mss = maxmtu - min_protoh) * probably violates the TCP spec. * The problem is that, since we don't know the * other end's MSS, we are supposed to use a conservative * default. But, if we do that, then MTU discovery will * never actually take place, because the conservative * default is much less than the MTUs typically seen * on the Internet today. For the moment, we'll sweep * this under the carpet. * * The conservative default might not actually be a problem * if the only case this occurs is when sending an initial * SYN with options and data to a host we've never talked * to before. Then, they will reply with an MSS value which * will get recorded and the new parameters should get * recomputed. For Further Study. */ } mss = min(mss, offer); /* * Sanity check: make sure that maxseg will be large * enough to allow some data on segments even if the * all the option space is used (40bytes). Otherwise * funny things may happen in tcp_output. * * XXXGL: shouldn't we reserve space for IP/IPv6 options? */ mss = max(mss, 64); tp->t_maxseg = mss; if (tp->t_maxseg < V_tcp_mssdflt) { /* * The MSS is so small we should not process incoming * SACK's since we are subject to attack in such a * case. */ tp->t_flags2 |= TF2_PROC_SACK_PROHIBIT; } else { tp->t_flags2 &= ~TF2_PROC_SACK_PROHIBIT; } } void tcp_mss(struct tcpcb *tp, int offer) { int mss; uint32_t bufsize; struct inpcb *inp = tptoinpcb(tp); struct socket *so; struct hc_metrics_lite metrics; struct tcp_ifcap cap; KASSERT(tp != NULL, ("%s: tp == NULL", __func__)); bzero(&cap, sizeof(cap)); tcp_mss_update(tp, offer, -1, &metrics, &cap); mss = tp->t_maxseg; /* * If there's a pipesize, change the socket buffer to that size, * don't change if sb_hiwat is different than default (then it * has been changed on purpose with setsockopt). * Make the socket buffers an integral number of mss units; * if the mss is larger than the socket buffer, decrease the mss. */ so = inp->inp_socket; - SOCKBUF_LOCK(&so->so_snd); + SOCK_SENDBUF_LOCK(so); if ((so->so_snd.sb_hiwat == V_tcp_sendspace) && metrics.rmx_sendpipe) bufsize = metrics.rmx_sendpipe; else bufsize = so->so_snd.sb_hiwat; if (bufsize < mss) mss = bufsize; else { bufsize = roundup(bufsize, mss); if (bufsize > sb_max) bufsize = sb_max; if (bufsize > so->so_snd.sb_hiwat) (void)sbreserve_locked(so, SO_SND, bufsize, NULL); } - SOCKBUF_UNLOCK(&so->so_snd); + SOCK_SENDBUF_UNLOCK(so); /* * Sanity check: make sure that maxseg will be large * enough to allow some data on segments even if the * all the option space is used (40bytes). Otherwise * funny things may happen in tcp_output. * * XXXGL: shouldn't we reserve space for IP/IPv6 options? */ tp->t_maxseg = max(mss, 64); if (tp->t_maxseg < V_tcp_mssdflt) { /* * The MSS is so small we should not process incoming * SACK's since we are subject to attack in such a * case. */ tp->t_flags2 |= TF2_PROC_SACK_PROHIBIT; } else { tp->t_flags2 &= ~TF2_PROC_SACK_PROHIBIT; } - SOCKBUF_LOCK(&so->so_rcv); + SOCK_RECVBUF_LOCK(so); if ((so->so_rcv.sb_hiwat == V_tcp_recvspace) && metrics.rmx_recvpipe) bufsize = metrics.rmx_recvpipe; else bufsize = so->so_rcv.sb_hiwat; if (bufsize > mss) { bufsize = roundup(bufsize, mss); if (bufsize > sb_max) bufsize = sb_max; if (bufsize > so->so_rcv.sb_hiwat) (void)sbreserve_locked(so, SO_RCV, bufsize, NULL); } - SOCKBUF_UNLOCK(&so->so_rcv); + SOCK_RECVBUF_UNLOCK(so); /* Check the interface for TSO capabilities. */ if (cap.ifcap & CSUM_TSO) { tp->t_flags |= TF_TSO; tp->t_tsomax = cap.tsomax; tp->t_tsomaxsegcount = cap.tsomaxsegcount; tp->t_tsomaxsegsize = cap.tsomaxsegsize; if (cap.ipsec_tso) tp->t_flags2 |= TF2_IPSEC_TSO; } } /* * Determine the MSS option to send on an outgoing SYN. */ int tcp_mssopt(struct in_conninfo *inc) { int mss = 0; uint32_t thcmtu = 0; uint32_t maxmtu = 0; size_t min_protoh; KASSERT(inc != NULL, ("tcp_mssopt with NULL in_conninfo pointer")); #ifdef INET6 if (inc->inc_flags & INC_ISIPV6) { mss = V_tcp_v6mssdflt; maxmtu = tcp_maxmtu6(inc, NULL); min_protoh = sizeof(struct ip6_hdr) + sizeof(struct tcphdr); } #endif #if defined(INET) && defined(INET6) else #endif #ifdef INET { mss = V_tcp_mssdflt; maxmtu = tcp_maxmtu(inc, NULL); min_protoh = sizeof(struct tcpiphdr); } #endif #if defined(INET6) || defined(INET) thcmtu = tcp_hc_getmtu(inc); /* IPv4 and IPv6 */ #endif if (maxmtu && thcmtu) mss = min(maxmtu, thcmtu) - min_protoh; else if (maxmtu || thcmtu) mss = max(maxmtu, thcmtu) - min_protoh; return (mss); } void tcp_do_prr_ack(struct tcpcb *tp, struct tcphdr *th, struct tcpopt *to, sackstatus_t sack_changed, u_int *maxsegp) { int snd_cnt = 0, limit = 0, del_data = 0, pipe = 0; u_int maxseg; INP_WLOCK_ASSERT(tptoinpcb(tp)); if (*maxsegp == 0) { *maxsegp = tcp_maxseg(tp); } maxseg = *maxsegp; /* * Compute the amount of data that this ACK is indicating * (del_data) and an estimate of how many bytes are in the * network. */ if (tcp_is_sack_recovery(tp, to) || (IN_CONGRECOVERY(tp->t_flags) && !IN_FASTRECOVERY(tp->t_flags))) { del_data = tp->sackhint.delivered_data; if (V_tcp_do_newsack) pipe = tcp_compute_pipe(tp); else pipe = (tp->snd_nxt - tp->snd_fack) + tp->sackhint.sack_bytes_rexmit; } else { if (tp->sackhint.prr_delivered < (tcprexmtthresh * maxseg + tp->snd_recover - tp->snd_una)) { del_data = maxseg; } pipe = imax(0, tp->snd_max - tp->snd_una - imin(INT_MAX / 65536, tp->t_dupacks) * maxseg); } tp->sackhint.prr_delivered += del_data; /* * Proportional Rate Reduction */ if (pipe >= tp->snd_ssthresh) { if (tp->sackhint.recover_fs == 0) tp->sackhint.recover_fs = imax(1, tp->snd_nxt - tp->snd_una); snd_cnt = howmany((long)tp->sackhint.prr_delivered * tp->snd_ssthresh, tp->sackhint.recover_fs) - tp->sackhint.prr_out + maxseg - 1; } else { /* * PRR 6937bis heuristic: * - A partial ack without SACK block beneath snd_recover * indicates further loss. * - An SACK scoreboard update adding a new hole indicates * further loss, so be conservative and send at most one * segment. * - Prevent ACK splitting attacks, by being conservative * when no new data is acked. */ if ((sack_changed == SACK_NEWLOSS) || (del_data == 0)) { limit = tp->sackhint.prr_delivered - tp->sackhint.prr_out; } else { limit = imax(tp->sackhint.prr_delivered - tp->sackhint.prr_out, del_data) + maxseg; } snd_cnt = imin((tp->snd_ssthresh - pipe), limit); } snd_cnt = imax(snd_cnt, 0) / maxseg; /* * Send snd_cnt new data into the network in response to this ack. * If there is going to be a SACK retransmission, adjust snd_cwnd * accordingly. */ if (IN_FASTRECOVERY(tp->t_flags)) { if (tcp_is_sack_recovery(tp, to)) { tp->snd_cwnd = pipe - del_data + (snd_cnt * maxseg); } else { tp->snd_cwnd = (tp->snd_max - tp->snd_una) + (snd_cnt * maxseg); } } else if (IN_CONGRECOVERY(tp->t_flags)) { tp->snd_cwnd = pipe - del_data + (snd_cnt * maxseg); } tp->snd_cwnd = imax(maxseg, tp->snd_cwnd); } /* * On a partial ack arrives, force the retransmission of the * next unacknowledged segment. Do not clear tp->t_dupacks. * By setting snd_nxt to ti_ack, this forces retransmission timer to * be started again. */ void tcp_newreno_partial_ack(struct tcpcb *tp, struct tcphdr *th) { tcp_seq onxt = tp->snd_nxt; uint32_t ocwnd = tp->snd_cwnd; u_int maxseg = tcp_maxseg(tp); INP_WLOCK_ASSERT(tptoinpcb(tp)); tcp_timer_activate(tp, TT_REXMT, 0); tp->t_rtttime = 0; if (IN_FASTRECOVERY(tp->t_flags)) { tp->snd_nxt = th->th_ack; /* * Set snd_cwnd to one segment beyond acknowledged offset. * (tp->snd_una has not yet been updated when this function is called.) */ tp->snd_cwnd = maxseg + BYTES_THIS_ACK(tp, th); tp->t_flags |= TF_ACKNOW; (void) tcp_output(tp); tp->snd_cwnd = ocwnd; if (SEQ_GT(onxt, tp->snd_nxt)) tp->snd_nxt = onxt; } /* * Partial window deflation. Relies on fact that tp->snd_una * not updated yet. */ if (tp->snd_cwnd > BYTES_THIS_ACK(tp, th)) tp->snd_cwnd -= BYTES_THIS_ACK(tp, th); else tp->snd_cwnd = 0; tp->snd_cwnd += maxseg; } int tcp_compute_pipe(struct tcpcb *tp) { if (tp->t_fb->tfb_compute_pipe == NULL) { return (tp->snd_max - tp->snd_una + tp->sackhint.sack_bytes_rexmit - tp->sackhint.sacked_bytes - tp->sackhint.lost_bytes); } else { return((*tp->t_fb->tfb_compute_pipe)(tp)); } } uint32_t tcp_compute_initwnd(uint32_t maxseg) { /* * Calculate the Initial Window, also used as Restart Window * * RFC5681 Section 3.1 specifies the default conservative values. * RFC3390 specifies slightly more aggressive values. * RFC6928 increases it to ten segments. * Support for user specified value for initial flight size. */ if (V_tcp_initcwnd_segments) return min(V_tcp_initcwnd_segments * maxseg, max(2 * maxseg, V_tcp_initcwnd_segments * 1460)); else if (V_tcp_do_rfc3390) return min(4 * maxseg, max(2 * maxseg, 4380)); else { /* Per RFC5681 Section 3.1 */ if (maxseg > 2190) return (2 * maxseg); else if (maxseg > 1095) return (3 * maxseg); else return (4 * maxseg); } } diff --git a/sys/netinet/tcp_output.c b/sys/netinet/tcp_output.c index 860b785b631b..8f19885f6b9b 100644 --- a/sys/netinet/tcp_output.c +++ b/sys/netinet/tcp_output.c @@ -1,2185 +1,2185 @@ /*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include #include "opt_inet.h" #include "opt_inet6.h" #include "opt_ipsec.h" #include "opt_kern_tls.h" #include #include #include #include #ifdef TCP_HHOOK #include #endif #include #ifdef KERN_TLS #include #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef INET6 #include #include #include #endif #include #define TCPOUTFLAGS #include #include #include #include #include #include #include #include #include #ifdef TCPPCAP #include #endif #ifdef TCP_OFFLOAD #include #endif #include #include #include #include #include #include VNET_DEFINE(int, path_mtu_discovery) = 1; SYSCTL_INT(_net_inet_tcp, OID_AUTO, path_mtu_discovery, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(path_mtu_discovery), 1, "Enable Path MTU Discovery"); VNET_DEFINE(int, tcp_do_tso) = 1; SYSCTL_INT(_net_inet_tcp, OID_AUTO, tso, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_do_tso), 0, "Enable TCP Segmentation Offload"); VNET_DEFINE(int, tcp_sendspace) = 1024*32; #define V_tcp_sendspace VNET(tcp_sendspace) SYSCTL_INT(_net_inet_tcp, TCPCTL_SENDSPACE, sendspace, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_sendspace), 0, "Initial send socket buffer size"); VNET_DEFINE(int, tcp_do_autosndbuf) = 1; SYSCTL_INT(_net_inet_tcp, OID_AUTO, sendbuf_auto, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_do_autosndbuf), 0, "Enable automatic send buffer sizing"); VNET_DEFINE(int, tcp_autosndbuf_inc) = 8*1024; SYSCTL_INT(_net_inet_tcp, OID_AUTO, sendbuf_inc, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_autosndbuf_inc), 0, "Incrementor step size of automatic send buffer"); VNET_DEFINE(int, tcp_autosndbuf_max) = 2*1024*1024; SYSCTL_INT(_net_inet_tcp, OID_AUTO, sendbuf_max, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_autosndbuf_max), 0, "Max size of automatic send buffer"); VNET_DEFINE(int, tcp_sendbuf_auto_lowat) = 0; #define V_tcp_sendbuf_auto_lowat VNET(tcp_sendbuf_auto_lowat) SYSCTL_INT(_net_inet_tcp, OID_AUTO, sendbuf_auto_lowat, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_sendbuf_auto_lowat), 0, "Modify threshold for auto send buffer growth to account for SO_SNDLOWAT"); /* * Make sure that either retransmit or persist timer is set for SYN, FIN and * non-ACK. */ #define TCP_XMIT_TIMER_ASSERT(tp, len, th_flags) \ KASSERT(((len) == 0 && ((th_flags) & (TH_SYN | TH_FIN)) == 0) ||\ tcp_timer_active((tp), TT_REXMT) || \ tcp_timer_active((tp), TT_PERSIST), \ ("neither rexmt nor persist timer is set")) #ifdef TCP_HHOOK /* * Wrapper for the TCP established output helper hook. */ void hhook_run_tcp_est_out(struct tcpcb *tp, struct tcphdr *th, struct tcpopt *to, uint32_t len, int tso) { struct tcp_hhook_data hhook_data; if (V_tcp_hhh[HHOOK_TCP_EST_OUT]->hhh_nhooks > 0) { hhook_data.tp = tp; hhook_data.th = th; hhook_data.to = to; hhook_data.len = len; hhook_data.tso = tso; hhook_run_hooks(V_tcp_hhh[HHOOK_TCP_EST_OUT], &hhook_data, &tp->t_osd); } } #endif /* * CC wrapper hook functions */ void cc_after_idle(struct tcpcb *tp) { INP_WLOCK_ASSERT(tptoinpcb(tp)); if (CC_ALGO(tp)->after_idle != NULL) CC_ALGO(tp)->after_idle(&tp->t_ccv); } /* * Tcp output routine: figure out what should be sent and send it. */ int tcp_default_output(struct tcpcb *tp) { struct socket *so = tptosocket(tp); struct inpcb *inp = tptoinpcb(tp); int32_t len; uint32_t recwin, sendwin; uint16_t flags; int off, error = 0; /* Keep compiler happy */ u_int if_hw_tsomaxsegcount = 0; u_int if_hw_tsomaxsegsize = 0; struct mbuf *m; struct ip *ip = NULL; struct tcphdr *th; u_char opt[TCP_MAXOLEN]; unsigned ipoptlen, optlen, hdrlen, ulen; unsigned ipsec_optlen = 0; int idle, sendalot, curticks; int sack_rxmit, sack_bytes_rxmt; struct sackhole *p; int tso, mtu; struct tcpopt to; struct udphdr *udp = NULL; struct tcp_log_buffer *lgb; unsigned int wanted_cookie = 0; unsigned int dont_sendalot = 0; #ifdef INET6 struct ip6_hdr *ip6 = NULL; const bool isipv6 = (inp->inp_vflag & INP_IPV6) != 0; #endif #ifdef KERN_TLS const bool hw_tls = tp->t_nic_ktls_xmit != 0; #else const bool hw_tls = false; #endif NET_EPOCH_ASSERT(); INP_WLOCK_ASSERT(inp); #ifdef TCP_OFFLOAD if (tp->t_flags & TF_TOE) return (tcp_offload_output(tp)); #endif /* * For TFO connections in SYN_SENT or SYN_RECEIVED, * only allow the initial SYN or SYN|ACK and those sent * by the retransmit timer. */ if ((tp->t_flags & TF_FASTOPEN) && ((tp->t_state == TCPS_SYN_SENT) || (tp->t_state == TCPS_SYN_RECEIVED)) && SEQ_GT(tp->snd_max, tp->snd_una) && /* SYN or SYN|ACK sent */ (tp->snd_nxt != tp->snd_una)) /* not a retransmit */ return (0); /* * Determine length of data that should be transmitted, * and flags that will be used. * If there is some data or critical controls (SYN, RST) * to send, then transmit; otherwise, investigate further. */ idle = (tp->t_flags & TF_LASTIDLE) || (tp->snd_max == tp->snd_una); if (idle && (((ticks - tp->t_rcvtime) >= tp->t_rxtcur) || (tp->t_sndtime && ((ticks - tp->t_sndtime) >= tp->t_rxtcur)))) cc_after_idle(tp); tp->t_flags &= ~TF_LASTIDLE; if (idle) { if (tp->t_flags & TF_MORETOCOME) { tp->t_flags |= TF_LASTIDLE; idle = 0; } } again: sendwin = 0; /* * If we've recently taken a timeout, snd_max will be greater than * snd_nxt. There may be SACK information that allows us to avoid * resending already delivered data. Adjust snd_nxt accordingly. */ if ((tp->t_flags & TF_SACK_PERMIT) && (tp->sackhint.nexthole != NULL) && !IN_FASTRECOVERY(tp->t_flags)) { sendwin = tcp_sack_adjust(tp); } sendalot = 0; tso = 0; mtu = 0; off = tp->snd_nxt - tp->snd_una; sendwin = min(tp->snd_wnd, tp->snd_cwnd + sendwin); flags = tcp_outflags[tp->t_state]; /* * Send any SACK-generated retransmissions. If we're explicitly trying * to send out new data (when sendalot is 1), bypass this function. * If we retransmit in fast recovery mode, decrement snd_cwnd, since * we're replacing a (future) new transmission with a retransmission * now, and we previously incremented snd_cwnd in tcp_input(). */ /* * Still in sack recovery , reset rxmit flag to zero. */ sack_rxmit = 0; sack_bytes_rxmt = 0; len = 0; p = NULL; if ((tp->t_flags & TF_SACK_PERMIT) && (IN_FASTRECOVERY(tp->t_flags) || SEQ_LT(tp->snd_nxt, tp->snd_max)) && (p = tcp_sack_output(tp, &sack_bytes_rxmt))) { int32_t cwin; if (IN_FASTRECOVERY(tp->t_flags)) { cwin = imax(sendwin - tcp_compute_pipe(tp), 0); } else { cwin = imax(sendwin - off, 0); } /* Do not retransmit SACK segments beyond snd_recover */ if (SEQ_GT(p->end, tp->snd_recover)) { /* * (At least) part of sack hole extends beyond * snd_recover. Check to see if we can rexmit data * for this hole. */ if (SEQ_GEQ(p->rxmit, tp->snd_recover)) { /* * Can't rexmit any more data for this hole. * That data will be rexmitted in the next * sack recovery episode, when snd_recover * moves past p->rxmit. */ p = NULL; goto after_sack_rexmit; } else { /* Can rexmit part of the current hole */ len = SEQ_SUB(tp->snd_recover, p->rxmit); if (cwin <= len) { len = cwin; } else { sendalot = 1; } } } else { len = SEQ_SUB(p->end, p->rxmit); if (cwin <= len) { len = cwin; } else { sendalot = 1; } } /* we could have transmitted from the scoreboard, * but sendwin (expected flightsize) - pipe didn't * allow any transmission. * Bypass recalculating the possible transmission * length further down by setting sack_rxmit. * Wouldn't be here if there would have been * nothing in the scoreboard to transmit. */ sack_rxmit = 1; if (len > 0) { off = SEQ_SUB(p->rxmit, tp->snd_una); KASSERT(off >= 0,("%s: sack block to the left of una : %d", __func__, off)); } } after_sack_rexmit: /* * Get standard flags, and add SYN or FIN if requested by 'hidden' * state flags. */ if (tp->t_flags & TF_NEEDFIN) flags |= TH_FIN; if (tp->t_flags & TF_NEEDSYN) flags |= TH_SYN; - SOCKBUF_LOCK(&so->so_snd); + SOCK_SENDBUF_LOCK(so); /* * If in persist timeout with window of 0, send 1 byte. * Otherwise, if window is small but nonzero * and timer expired, we will send what we can * and go to transmit state. */ if (tp->t_flags & TF_FORCEDATA) { if (sendwin == 0) { /* * If we still have some data to send, then * clear the FIN bit. Usually this would * happen below when it realizes that we * aren't sending all the data. However, * if we have exactly 1 byte of unsent data, * then it won't clear the FIN bit below, * and if we are in persist state, we wind * up sending the packet without recording * that we sent the FIN bit. * * We can't just blindly clear the FIN bit, * because if we don't have any more data * to send then the probe will be the FIN * itself. */ if (off < sbused(&so->so_snd)) flags &= ~TH_FIN; sendwin = 1; } else { tcp_timer_activate(tp, TT_PERSIST, 0); tp->t_rxtshift = 0; } } /* * If snd_nxt == snd_max and we have transmitted a FIN, the * offset will be > 0 even if so_snd.sb_cc is 0, resulting in * a negative length. This can also occur when TCP opens up * its congestion window while receiving additional duplicate * acks after fast-retransmit because TCP will reset snd_nxt * to snd_max after the fast-retransmit. * * In the normal retransmit-FIN-only case, however, snd_nxt will * be set to snd_una, the offset will be 0, and the length may * wind up 0. * * If sack_rxmit is true we are retransmitting from the scoreboard * in which case len is already set. */ if (sack_rxmit == 0) { if ((sack_bytes_rxmt == 0) || SEQ_LT(tp->snd_nxt, tp->snd_max)) { len = imin(sbavail(&so->so_snd), sendwin) - off; } else { /* * We are inside of a SACK recovery episode and are * sending new data, having retransmitted all the * data possible in the scoreboard. */ len = imin(sbavail(&so->so_snd) - off, sendwin - tcp_compute_pipe(tp)); } } /* * Lop off SYN bit if it has already been sent. However, if this * is SYN-SENT state and if segment contains data and if we don't * know that foreign host supports TAO, suppress sending segment. */ if ((flags & TH_SYN) && SEQ_GT(tp->snd_nxt, tp->snd_una)) { if (tp->t_state != TCPS_SYN_RECEIVED) flags &= ~TH_SYN; /* * When sending additional segments following a TFO SYN|ACK, * do not include the SYN bit. */ if ((tp->t_flags & TF_FASTOPEN) && (tp->t_state == TCPS_SYN_RECEIVED)) flags &= ~TH_SYN; off--, len++; } /* * Be careful not to send data and/or FIN on SYN segments. * This measure is needed to prevent interoperability problems * with not fully conformant TCP implementations. */ if ((flags & TH_SYN) && (tp->t_flags & TF_NOOPT)) { len = 0; flags &= ~TH_FIN; } /* * On TFO sockets, ensure no data is sent in the following cases: * * - When retransmitting SYN|ACK on a passively-created socket * * - When retransmitting SYN on an actively created socket * * - When sending a zero-length cookie (cookie request) on an * actively created socket * * - When the socket is in the CLOSED state (RST is being sent) */ if ((tp->t_flags & TF_FASTOPEN) && (((flags & TH_SYN) && (tp->t_rxtshift > 0)) || ((tp->t_state == TCPS_SYN_SENT) && (tp->t_tfo_client_cookie_len == 0)) || (flags & TH_RST))) len = 0; /* Without fast-open there should never be data sent on a SYN. */ if ((flags & TH_SYN) && !(tp->t_flags & TF_FASTOPEN)) { len = 0; } if (len <= 0) { /* * If FIN has been sent but not acked, * but we haven't been called to retransmit, * len will be < 0. Otherwise, window shrank * after we sent into it. If window shrank to 0, * cancel pending retransmit, pull snd_nxt back * to (closed) window, and set the persist timer * if it isn't already going. If the window didn't * close completely, just wait for an ACK. * * We also do a general check here to ensure that * we will set the persist timer when we have data * to send, but a 0-byte window. This makes sure * the persist timer is set even if the packet * hits one of the "goto send" lines below. */ len = 0; if ((sendwin == 0) && (TCPS_HAVEESTABLISHED(tp->t_state)) && (off < (int) sbavail(&so->so_snd)) && !tcp_timer_active(tp, TT_PERSIST)) { tcp_timer_activate(tp, TT_REXMT, 0); tp->t_rxtshift = 0; tp->snd_nxt = tp->snd_una; if (!tcp_timer_active(tp, TT_PERSIST)) tcp_setpersist(tp); } } /* len will be >= 0 after this point. */ KASSERT(len >= 0, ("[%s:%d]: len < 0", __func__, __LINE__)); tcp_sndbuf_autoscale(tp, so, sendwin); /* * Decide if we can use TCP Segmentation Offloading (if supported by * hardware). * * TSO may only be used if we are in a pure bulk sending state. The * presence of TCP-MD5, SACK retransmits, SACK advertizements and * IP options prevent using TSO. With TSO the TCP header is the same * (except for the sequence number) for all generated packets. This * makes it impossible to transmit any options which vary per generated * segment or packet. * * IPv4 handling has a clear separation of ip options and ip header * flags while IPv6 combines both in in6p_outputopts. ip6_optlen() does * the right thing below to provide length of just ip options and thus * checking for ipoptlen is enough to decide if ip options are present. */ #if defined(IPSEC) || defined(IPSEC_SUPPORT) /* * Pre-calculate here as we save another lookup into the darknesses * of IPsec that way and can actually decide if TSO is ok. */ #ifdef INET6 if (isipv6 && IPSEC_ENABLED(ipv6)) ipsec_optlen = IPSEC_HDRSIZE(ipv6, inp); #ifdef INET else #endif #endif /* INET6 */ #ifdef INET if (IPSEC_ENABLED(ipv4)) ipsec_optlen = IPSEC_HDRSIZE(ipv4, inp); #endif /* INET */ #endif /* IPSEC */ #ifdef INET6 if (isipv6) ipoptlen = ip6_optlen(inp); else #endif if (inp->inp_options) ipoptlen = inp->inp_options->m_len - offsetof(struct ipoption, ipopt_list); else ipoptlen = 0; ipoptlen += ipsec_optlen; if ((tp->t_flags & TF_TSO) && V_tcp_do_tso && len > tp->t_maxseg && (tp->t_port == 0) && ((tp->t_flags & TF_SIGNATURE) == 0) && tp->rcv_numsacks == 0 && ((sack_rxmit == 0) || V_tcp_sack_tso) && (ipoptlen == 0 || (ipoptlen == ipsec_optlen && (tp->t_flags2 & TF2_IPSEC_TSO) != 0)) && !(flags & TH_SYN)) tso = 1; if (SEQ_LT((sack_rxmit ? p->rxmit : tp->snd_nxt) + len, tp->snd_una + sbused(&so->so_snd))) { flags &= ~TH_FIN; } recwin = lmin(lmax(sbspace(&so->so_rcv), 0), (long)TCP_MAXWIN << tp->rcv_scale); /* * Sender silly window avoidance. We transmit under the following * conditions when len is non-zero: * * - We have a full segment (or more with TSO) * - This is the last buffer in a write()/send() and we are * either idle or running NODELAY * - we've timed out (e.g. persist timer) * - we have more then 1/2 the maximum send window's worth of * data (receiver may be limited the window size) * - we need to retransmit */ if (len) { if (len >= tp->t_maxseg) goto send; /* * As the TCP header options are now * considered when setting up the initial * window, we would not send the last segment * if we skip considering the option length here. * Note: this may not work when tcp headers change * very dynamically in the future. */ if ((((tp->t_flags & TF_SIGNATURE) ? PADTCPOLEN(TCPOLEN_SIGNATURE) : 0) + ((tp->t_flags & TF_RCVD_TSTMP) ? PADTCPOLEN(TCPOLEN_TIMESTAMP) : 0) + len) >= tp->t_maxseg) goto send; /* * NOTE! on localhost connections an 'ack' from the remote * end may occur synchronously with the output and cause * us to flush a buffer queued with moretocome. XXX * * note: the len + off check is almost certainly unnecessary. */ if (!(tp->t_flags & TF_MORETOCOME) && /* normal case */ (idle || (tp->t_flags & TF_NODELAY)) && (uint32_t)len + (uint32_t)off >= sbavail(&so->so_snd) && (tp->t_flags & TF_NOPUSH) == 0) { goto send; } if (tp->t_flags & TF_FORCEDATA) /* typ. timeout case */ goto send; if (len >= tp->max_sndwnd / 2 && tp->max_sndwnd > 0) goto send; if (SEQ_LT(tp->snd_nxt, tp->snd_max)) /* retransmit case */ goto send; if (sack_rxmit) goto send; } /* * Sending of standalone window updates. * * Window updates are important when we close our window due to a * full socket buffer and are opening it again after the application * reads data from it. Once the window has opened again and the * remote end starts to send again the ACK clock takes over and * provides the most current window information. * * We must avoid the silly window syndrome whereas every read * from the receive buffer, no matter how small, causes a window * update to be sent. We also should avoid sending a flurry of * window updates when the socket buffer had queued a lot of data * and the application is doing small reads. * * Prevent a flurry of pointless window updates by only sending * an update when we can increase the advertized window by more * than 1/4th of the socket buffer capacity. When the buffer is * getting full or is very small be more aggressive and send an * update whenever we can increase by two mss sized segments. * In all other situations the ACK's to new incoming data will * carry further window increases. * * Don't send an independent window update if a delayed * ACK is pending (it will get piggy-backed on it) or the * remote side already has done a half-close and won't send * more data. */ if (recwin > 0 && !(tp->t_flags & TF_NEEDSYN) && !(tp->t_flags & TF_DELACK) && !TCPS_HAVERCVDFIN(tp->t_state)) { /* * "adv" is the amount we could increase the window, * taking into account that we are limited by * TCP_MAXWIN << tp->rcv_scale. */ int32_t adv; int oldwin; adv = recwin; if (SEQ_GT(tp->rcv_adv, tp->rcv_nxt)) { oldwin = (tp->rcv_adv - tp->rcv_nxt); if (adv > oldwin) adv -= oldwin; else adv = 0; } else oldwin = 0; /* * If the new window size ends up being the same as or less * than the old size when it is scaled, then don't force * a window update. */ if (oldwin >> tp->rcv_scale >= (adv + oldwin) >> tp->rcv_scale) goto dontupdate; if (adv >= (int32_t)(2 * tp->t_maxseg) && (adv >= (int32_t)(so->so_rcv.sb_hiwat / 4) || recwin <= (so->so_rcv.sb_hiwat / 8) || so->so_rcv.sb_hiwat <= 8 * tp->t_maxseg || adv >= TCP_MAXWIN << tp->rcv_scale)) goto send; if (2 * adv >= (int32_t)so->so_rcv.sb_hiwat) goto send; } dontupdate: /* * Send if we owe the peer an ACK, RST, SYN, or urgent data. ACKNOW * is also a catch-all for the retransmit timer timeout case. */ if (tp->t_flags & TF_ACKNOW) goto send; if ((flags & TH_RST) || ((flags & TH_SYN) && (tp->t_flags & TF_NEEDSYN) == 0)) goto send; if (SEQ_GT(tp->snd_up, tp->snd_una)) goto send; /* * If our state indicates that FIN should be sent * and we have not yet done so, then we need to send. */ if (flags & TH_FIN && ((tp->t_flags & TF_SENTFIN) == 0 || tp->snd_nxt == tp->snd_una)) goto send; /* * In SACK, it is possible for tcp_output to fail to send a segment * after the retransmission timer has been turned off. Make sure * that the retransmission timer is set. */ if ((tp->t_flags & TF_SACK_PERMIT) && SEQ_GT(tp->snd_max, tp->snd_una) && !tcp_timer_active(tp, TT_REXMT) && !tcp_timer_active(tp, TT_PERSIST)) { tcp_timer_activate(tp, TT_REXMT, TP_RXTCUR(tp)); goto just_return; } /* * TCP window updates are not reliable, rather a polling protocol * using ``persist'' packets is used to insure receipt of window * updates. The three ``states'' for the output side are: * idle not doing retransmits or persists * persisting to move a small or zero window * (re)transmitting and thereby not persisting * * tcp_timer_active(tp, TT_PERSIST) * is true when we are in persist state. * (tp->t_flags & TF_FORCEDATA) * is set when we are called to send a persist packet. * tcp_timer_active(tp, TT_REXMT) * is set when we are retransmitting * The output side is idle when both timers are zero. * * If send window is too small, there is data to transmit, and no * retransmit or persist is pending, then go to persist state. * If nothing happens soon, send when timer expires: * if window is nonzero, transmit what we can, * otherwise force out a byte. */ if (sbavail(&so->so_snd) && !tcp_timer_active(tp, TT_REXMT) && !tcp_timer_active(tp, TT_PERSIST)) { tp->t_rxtshift = 0; tcp_setpersist(tp); } /* * No reason to send a segment, just return. */ just_return: - SOCKBUF_UNLOCK(&so->so_snd); + SOCK_SENDBUF_UNLOCK(so); return (0); send: - SOCKBUF_LOCK_ASSERT(&so->so_snd); + SOCK_SENDBUF_LOCK_ASSERT(so); if (len > 0) { if (len >= tp->t_maxseg) tp->t_flags2 |= TF2_PLPMTU_MAXSEGSNT; else tp->t_flags2 &= ~TF2_PLPMTU_MAXSEGSNT; } /* * Before ESTABLISHED, force sending of initial options * unless TCP set not to do any options. * NOTE: we assume that the IP/TCP header plus TCP options * always fit in a single mbuf, leaving room for a maximum * link header, i.e. * max_linkhdr + sizeof (struct tcpiphdr) + optlen <= MCLBYTES */ optlen = 0; #ifdef INET6 if (isipv6) hdrlen = sizeof (struct ip6_hdr) + sizeof (struct tcphdr); else #endif hdrlen = sizeof (struct tcpiphdr); if (flags & TH_SYN) { tp->snd_nxt = tp->iss; } /* * Compute options for segment. * We only have to care about SYN and established connection * segments. Options for SYN-ACK segments are handled in TCP * syncache. */ to.to_flags = 0; if ((tp->t_flags & TF_NOOPT) == 0) { /* Maximum segment size. */ if (flags & TH_SYN) { to.to_mss = tcp_mssopt(&inp->inp_inc); if (tp->t_port) to.to_mss -= V_tcp_udp_tunneling_overhead; to.to_flags |= TOF_MSS; /* * On SYN or SYN|ACK transmits on TFO connections, * only include the TFO option if it is not a * retransmit, as the presence of the TFO option may * have caused the original SYN or SYN|ACK to have * been dropped by a middlebox. */ if ((tp->t_flags & TF_FASTOPEN) && (tp->t_rxtshift == 0)) { if (tp->t_state == TCPS_SYN_RECEIVED) { to.to_tfo_len = TCP_FASTOPEN_COOKIE_LEN; to.to_tfo_cookie = (u_int8_t *)&tp->t_tfo_cookie.server; to.to_flags |= TOF_FASTOPEN; wanted_cookie = 1; } else if (tp->t_state == TCPS_SYN_SENT) { to.to_tfo_len = tp->t_tfo_client_cookie_len; to.to_tfo_cookie = tp->t_tfo_cookie.client; to.to_flags |= TOF_FASTOPEN; wanted_cookie = 1; /* * If we wind up having more data to * send with the SYN than can fit in * one segment, don't send any more * until the SYN|ACK comes back from * the other end. */ dont_sendalot = 1; } } } /* Window scaling. */ if ((flags & TH_SYN) && (tp->t_flags & TF_REQ_SCALE)) { to.to_wscale = tp->request_r_scale; to.to_flags |= TOF_SCALE; } /* Timestamps. */ if ((tp->t_flags & TF_RCVD_TSTMP) || ((flags & TH_SYN) && (tp->t_flags & TF_REQ_TSTMP))) { curticks = tcp_ts_getticks(); to.to_tsval = curticks + tp->ts_offset; to.to_tsecr = tp->ts_recent; to.to_flags |= TOF_TS; if (tp->t_rxtshift == 1) tp->t_badrxtwin = curticks; } /* Set receive buffer autosizing timestamp. */ if (tp->rfbuf_ts == 0 && (so->so_rcv.sb_flags & SB_AUTOSIZE)) tp->rfbuf_ts = tcp_ts_getticks(); /* Selective ACK's. */ if (tp->t_flags & TF_SACK_PERMIT) { if (flags & TH_SYN) to.to_flags |= TOF_SACKPERM; else if (TCPS_HAVEESTABLISHED(tp->t_state) && tp->rcv_numsacks > 0) { to.to_flags |= TOF_SACK; to.to_nsacks = tp->rcv_numsacks; to.to_sacks = (u_char *)tp->sackblks; } } #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) /* TCP-MD5 (RFC2385). */ /* * Check that TCP_MD5SIG is enabled in tcpcb to * account the size needed to set this TCP option. */ if (tp->t_flags & TF_SIGNATURE) to.to_flags |= TOF_SIGNATURE; #endif /* TCP_SIGNATURE */ /* Processing the options. */ hdrlen += optlen = tcp_addoptions(&to, opt); /* * If we wanted a TFO option to be added, but it was unable * to fit, ensure no data is sent. */ if ((tp->t_flags & TF_FASTOPEN) && wanted_cookie && !(to.to_flags & TOF_FASTOPEN)) len = 0; } if (tp->t_port) { if (V_tcp_udp_tunneling_port == 0) { /* The port was removed?? */ - SOCKBUF_UNLOCK(&so->so_snd); + SOCK_SENDBUF_UNLOCK(so); return (EHOSTUNREACH); } hdrlen += sizeof(struct udphdr); } /* * Adjust data length if insertion of options will * bump the packet length beyond the t_maxseg length. * Clear the FIN bit because we cut off the tail of * the segment. */ if (len + optlen + ipoptlen > tp->t_maxseg) { flags &= ~TH_FIN; if (tso) { u_int if_hw_tsomax; u_int moff; int max_len; /* extract TSO information */ if_hw_tsomax = tp->t_tsomax; if_hw_tsomaxsegcount = tp->t_tsomaxsegcount; if_hw_tsomaxsegsize = tp->t_tsomaxsegsize; /* * Limit a TSO burst to prevent it from * overflowing or exceeding the maximum length * allowed by the network interface: */ KASSERT(ipoptlen == ipsec_optlen, ("%s: TSO can't do IP options", __func__)); /* * Check if we should limit by maximum payload * length: */ if (if_hw_tsomax != 0) { /* compute maximum TSO length */ max_len = if_hw_tsomax - hdrlen - ipsec_optlen - max_linkhdr; if (max_len <= 0) { len = 0; } else if (len > max_len) { sendalot = 1; len = max_len; } } /* * Prevent the last segment from being * fractional unless the send sockbuf can be * emptied: */ max_len = tp->t_maxseg - optlen - ipsec_optlen; if (((uint32_t)off + (uint32_t)len) < sbavail(&so->so_snd)) { moff = len % max_len; if (moff != 0) { len -= moff; sendalot = 1; } } /* * In case there are too many small fragments * don't use TSO: */ if (len <= max_len) { len = max_len; sendalot = 1; tso = 0; } /* * Send the FIN in a separate segment * after the bulk sending is done. * We don't trust the TSO implementations * to clear the FIN flag on all but the * last segment. */ if (tp->t_flags & TF_NEEDFIN) sendalot = 1; } else { if (optlen + ipoptlen >= tp->t_maxseg) { /* * Since we don't have enough space to put * the IP header chain and the TCP header in * one packet as required by RFC 7112, don't * send it. Also ensure that at least one * byte of the payload can be put into the * TCP segment. */ - SOCKBUF_UNLOCK(&so->so_snd); + SOCK_SENDBUF_UNLOCK(so); error = EMSGSIZE; sack_rxmit = 0; goto out; } len = tp->t_maxseg - optlen - ipoptlen; sendalot = 1; if (dont_sendalot) sendalot = 0; } } else tso = 0; KASSERT(len + hdrlen + ipoptlen <= IP_MAXPACKET, ("%s: len > IP_MAXPACKET", __func__)); /*#ifdef DIAGNOSTIC*/ #ifdef INET6 if (max_linkhdr + hdrlen > MCLBYTES) #else if (max_linkhdr + hdrlen > MHLEN) #endif panic("tcphdr too big"); /*#endif*/ /* * This KASSERT is here to catch edge cases at a well defined place. * Before, those had triggered (random) panic conditions further down. */ KASSERT(len >= 0, ("[%s:%d]: len < 0", __func__, __LINE__)); /* * Grab a header mbuf, attaching a copy of data to * be transmitted, and initialize the header from * the template for sends on this connection. */ if (len) { struct mbuf *mb; struct sockbuf *msb; u_int moff; if ((tp->t_flags & TF_FORCEDATA) && len == 1) { TCPSTAT_INC(tcps_sndprobe); #ifdef STATS if (SEQ_LT(tp->snd_nxt, tp->snd_max)) stats_voi_update_abs_u32(tp->t_stats, VOI_TCP_RETXPB, len); else stats_voi_update_abs_u64(tp->t_stats, VOI_TCP_TXPB, len); #endif /* STATS */ } else if (SEQ_LT(tp->snd_nxt, tp->snd_max) || sack_rxmit) { tp->t_sndrexmitpack++; TCPSTAT_INC(tcps_sndrexmitpack); TCPSTAT_ADD(tcps_sndrexmitbyte, len); if (sack_rxmit) { TCPSTAT_INC(tcps_sack_rexmits); if (tso) { TCPSTAT_INC(tcps_sack_rexmits_tso); } TCPSTAT_ADD(tcps_sack_rexmit_bytes, len); } #ifdef STATS stats_voi_update_abs_u32(tp->t_stats, VOI_TCP_RETXPB, len); #endif /* STATS */ } else { TCPSTAT_INC(tcps_sndpack); TCPSTAT_ADD(tcps_sndbyte, len); #ifdef STATS stats_voi_update_abs_u64(tp->t_stats, VOI_TCP_TXPB, len); #endif /* STATS */ } #ifdef INET6 if (MHLEN < hdrlen + max_linkhdr) m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR); else #endif m = m_gethdr(M_NOWAIT, MT_DATA); if (m == NULL) { - SOCKBUF_UNLOCK(&so->so_snd); + SOCK_SENDBUF_UNLOCK(so); error = ENOBUFS; sack_rxmit = 0; goto out; } m->m_data += max_linkhdr; m->m_len = hdrlen; /* * Start the m_copy functions from the closest mbuf * to the offset in the socket buffer chain. */ mb = sbsndptr_noadv(&so->so_snd, off, &moff); if (len <= MHLEN - hdrlen - max_linkhdr && !hw_tls) { m_copydata(mb, moff, len, mtod(m, caddr_t) + hdrlen); if (SEQ_LT(tp->snd_nxt, tp->snd_max)) sbsndptr_adv(&so->so_snd, mb, len); m->m_len += len; } else { int32_t old_len; if (SEQ_LT(tp->snd_nxt, tp->snd_max)) msb = NULL; else msb = &so->so_snd; old_len = len; m->m_next = tcp_m_copym(mb, moff, &len, if_hw_tsomaxsegcount, if_hw_tsomaxsegsize, msb, hw_tls); if (old_len != len) flags &= ~TH_FIN; if (len <= (tp->t_maxseg - optlen)) { /* * Must have ran out of mbufs for the copy * shorten it to no longer need tso. Lets * not put on sendalot since we are low on * mbufs. */ tso = 0; } if (m->m_next == NULL) { - SOCKBUF_UNLOCK(&so->so_snd); + SOCK_SENDBUF_UNLOCK(so); (void) m_free(m); error = ENOBUFS; sack_rxmit = 0; goto out; } } /* * If we're sending everything we've got, set PUSH. * (This will keep happy those implementations which only * give data to the user when a buffer fills or * a PUSH comes in.) */ if (((uint32_t)off + (uint32_t)len == sbused(&so->so_snd)) && !(flags & TH_SYN)) flags |= TH_PUSH; - SOCKBUF_UNLOCK(&so->so_snd); + SOCK_SENDBUF_UNLOCK(so); } else { - SOCKBUF_UNLOCK(&so->so_snd); + SOCK_SENDBUF_UNLOCK(so); if (tp->t_flags & TF_ACKNOW) TCPSTAT_INC(tcps_sndacks); else if (flags & (TH_SYN|TH_FIN|TH_RST)) TCPSTAT_INC(tcps_sndctrl); else if (SEQ_GT(tp->snd_up, tp->snd_una)) TCPSTAT_INC(tcps_sndurg); else TCPSTAT_INC(tcps_sndwinup); m = m_gethdr(M_NOWAIT, MT_DATA); if (m == NULL) { error = ENOBUFS; sack_rxmit = 0; goto out; } #ifdef INET6 if (isipv6 && (MHLEN < hdrlen + max_linkhdr) && MHLEN >= hdrlen) { M_ALIGN(m, hdrlen); } else #endif m->m_data += max_linkhdr; m->m_len = hdrlen; } - SOCKBUF_UNLOCK_ASSERT(&so->so_snd); + SOCK_SENDBUF_UNLOCK_ASSERT(so); m->m_pkthdr.rcvif = (struct ifnet *)0; #ifdef MAC mac_inpcb_create_mbuf(inp, m); #endif #ifdef INET6 if (isipv6) { ip6 = mtod(m, struct ip6_hdr *); if (tp->t_port) { udp = (struct udphdr *)((caddr_t)ip6 + sizeof(struct ip6_hdr)); udp->uh_sport = htons(V_tcp_udp_tunneling_port); udp->uh_dport = tp->t_port; ulen = hdrlen + len - sizeof(struct ip6_hdr); udp->uh_ulen = htons(ulen); th = (struct tcphdr *)(udp + 1); } else { th = (struct tcphdr *)(ip6 + 1); } tcpip_fillheaders(inp, tp->t_port, ip6, th); } else #endif /* INET6 */ { ip = mtod(m, struct ip *); if (tp->t_port) { udp = (struct udphdr *)((caddr_t)ip + sizeof(struct ip)); udp->uh_sport = htons(V_tcp_udp_tunneling_port); udp->uh_dport = tp->t_port; ulen = hdrlen + len - sizeof(struct ip); udp->uh_ulen = htons(ulen); th = (struct tcphdr *)(udp + 1); } else th = (struct tcphdr *)(ip + 1); tcpip_fillheaders(inp, tp->t_port, ip, th); } /* * Fill in fields, remembering maximum advertised * window for use in delaying messages about window sizes. * If resending a FIN, be sure not to use a new sequence number. */ if (flags & TH_FIN && tp->t_flags & TF_SENTFIN && tp->snd_nxt == tp->snd_max) tp->snd_nxt--; /* * If we are starting a connection, send ECN setup * SYN packet. If we are on a retransmit, we may * resend those bits a number of times as per * RFC 3168. */ if (tp->t_state == TCPS_SYN_SENT && V_tcp_do_ecn) { flags |= tcp_ecn_output_syn_sent(tp); } /* Also handle parallel SYN for ECN */ if ((TCPS_HAVERCVDSYN(tp->t_state)) && (tp->t_flags2 & (TF2_ECN_PERMIT | TF2_ACE_PERMIT))) { int ect = tcp_ecn_output_established(tp, &flags, len, sack_rxmit); if ((tp->t_state == TCPS_SYN_RECEIVED) && (tp->t_flags2 & TF2_ECN_SND_ECE)) tp->t_flags2 &= ~TF2_ECN_SND_ECE; #ifdef INET6 if (isipv6) { ip6->ip6_flow &= ~htonl(IPTOS_ECN_MASK << IPV6_FLOWLABEL_LEN); ip6->ip6_flow |= htonl(ect << IPV6_FLOWLABEL_LEN); } else #endif { ip->ip_tos &= ~IPTOS_ECN_MASK; ip->ip_tos |= ect; } } /* * If we are doing retransmissions, then snd_nxt will * not reflect the first unsent octet. For ACK only * packets, we do not want the sequence number of the * retransmitted packet, we want the sequence number * of the next unsent octet. So, if there is no data * (and no SYN or FIN), use snd_max instead of snd_nxt * when filling in ti_seq. But if we are in persist * state, snd_max might reflect one byte beyond the * right edge of the window, so use snd_nxt in that * case, since we know we aren't doing a retransmission. * (retransmit and persist are mutually exclusive...) */ if (sack_rxmit == 0) { if (len || (flags & (TH_SYN|TH_FIN)) || tcp_timer_active(tp, TT_PERSIST)) th->th_seq = htonl(tp->snd_nxt); else th->th_seq = htonl(tp->snd_max); } else { th->th_seq = htonl(p->rxmit); p->rxmit += len; /* * Lost Retransmission Detection * trigger resending of a (then * still existing) hole, when * fack acks recoverypoint. */ if ((tp->t_flags & TF_LRD) && SEQ_GEQ(p->rxmit, p->end)) p->rxmit = tp->snd_recover; tp->sackhint.sack_bytes_rexmit += len; } if (IN_RECOVERY(tp->t_flags)) { /* * Account all bytes transmitted while * IN_RECOVERY, simplifying PRR and * Lost Retransmit Detection */ tp->sackhint.prr_out += len; } th->th_ack = htonl(tp->rcv_nxt); if (optlen) { bcopy(opt, th + 1, optlen); th->th_off = (sizeof (struct tcphdr) + optlen) >> 2; } tcp_set_flags(th, flags); /* * Calculate receive window. Don't shrink window, * but avoid silly window syndrome. * If a RST segment is sent, advertise a window of zero. */ if (flags & TH_RST) { recwin = 0; } else { if (recwin < (so->so_rcv.sb_hiwat / 4) && recwin < tp->t_maxseg) recwin = 0; if (SEQ_GT(tp->rcv_adv, tp->rcv_nxt) && recwin < (tp->rcv_adv - tp->rcv_nxt)) recwin = (tp->rcv_adv - tp->rcv_nxt); } /* * According to RFC1323 the window field in a SYN (i.e., a * or ) segment itself is never scaled. The * case is handled in syncache. */ if (flags & TH_SYN) th->th_win = htons((u_short) (min(sbspace(&so->so_rcv), TCP_MAXWIN))); else { /* Avoid shrinking window with window scaling. */ recwin = roundup2(recwin, 1 << tp->rcv_scale); th->th_win = htons((u_short)(recwin >> tp->rcv_scale)); } /* * Adjust the RXWIN0SENT flag - indicate that we have advertised * a 0 window. This may cause the remote transmitter to stall. This * flag tells soreceive() to disable delayed acknowledgements when * draining the buffer. This can occur if the receiver is attempting * to read more data than can be buffered prior to transmitting on * the connection. */ if (th->th_win == 0) { tp->t_sndzerowin++; tp->t_flags |= TF_RXWIN0SENT; } else tp->t_flags &= ~TF_RXWIN0SENT; if (SEQ_GT(tp->snd_up, tp->snd_nxt)) { th->th_urp = htons((u_short)(tp->snd_up - tp->snd_nxt)); th->th_flags |= TH_URG; } else /* * If no urgent pointer to send, then we pull * the urgent pointer to the left edge of the send window * so that it doesn't drift into the send window on sequence * number wraparound. */ tp->snd_up = tp->snd_una; /* drag it along */ /* * Put TCP length in extended header, and then * checksum extended header and data. */ m->m_pkthdr.len = hdrlen + len; /* in6_cksum() need this */ #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) if (to.to_flags & TOF_SIGNATURE) { /* * Calculate MD5 signature and put it into the place * determined before. * NOTE: since TCP options buffer doesn't point into * mbuf's data, calculate offset and use it. */ if (!TCPMD5_ENABLED() || (error = TCPMD5_OUTPUT(m, th, (u_char *)(th + 1) + (to.to_signature - opt))) != 0) { /* * Do not send segment if the calculation of MD5 * digest has failed. */ m_freem(m); goto out; } } #endif #ifdef INET6 if (isipv6) { /* * There is no need to fill in ip6_plen right now. * It will be filled later by ip6_output. */ if (tp->t_port) { m->m_pkthdr.csum_flags = CSUM_UDP_IPV6; m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); udp->uh_sum = in6_cksum_pseudo(ip6, ulen, IPPROTO_UDP, 0); th->th_sum = htons(0); UDPSTAT_INC(udps_opackets); } else { m->m_pkthdr.csum_flags = CSUM_TCP_IPV6; m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); th->th_sum = in6_cksum_pseudo(ip6, sizeof(struct tcphdr) + optlen + len, IPPROTO_TCP, 0); } } #endif #if defined(INET6) && defined(INET) else #endif #ifdef INET { if (tp->t_port) { m->m_pkthdr.csum_flags = CSUM_UDP; m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); udp->uh_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, htons(ulen + IPPROTO_UDP)); th->th_sum = htons(0); UDPSTAT_INC(udps_opackets); } else { m->m_pkthdr.csum_flags = CSUM_TCP; m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); th->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, htons(sizeof(struct tcphdr) + IPPROTO_TCP + len + optlen)); } /* IP version must be set here for ipv4/ipv6 checking later */ KASSERT(ip->ip_v == IPVERSION, ("%s: IP version incorrect: %d", __func__, ip->ip_v)); } #endif /* * Enable TSO and specify the size of the segments. * The TCP pseudo header checksum is always provided. */ if (tso) { KASSERT(len > tp->t_maxseg - optlen - ipsec_optlen, ("%s: len <= tso_segsz", __func__)); m->m_pkthdr.csum_flags |= CSUM_TSO; m->m_pkthdr.tso_segsz = tp->t_maxseg - optlen - ipsec_optlen; } KASSERT(len + hdrlen == m_length(m, NULL), ("%s: mbuf chain shorter than expected: %d + %u != %u", __func__, len, hdrlen, m_length(m, NULL))); #ifdef TCP_HHOOK /* Run HHOOK_TCP_ESTABLISHED_OUT helper hooks. */ hhook_run_tcp_est_out(tp, th, &to, len, tso); #endif TCP_PROBE3(debug__output, tp, th, m); /* We're getting ready to send; log now. */ /* XXXMT: We are not honoring verbose logging. */ if (tcp_bblogging_on(tp)) lgb = tcp_log_event(tp, th, &so->so_rcv, &so->so_snd, TCP_LOG_OUT, ERRNO_UNK, len, NULL, false, NULL, NULL, 0, NULL); else lgb = NULL; /* * Fill in IP length and desired time to live and * send to IP level. There should be a better way * to handle ttl and tos; we could keep them in * the template, but need a way to checksum without them. */ /* * m->m_pkthdr.len should have been set before checksum calculation, * because in6_cksum() need it. */ #ifdef INET6 if (isipv6) { /* * we separately set hoplimit for every segment, since the * user might want to change the value via setsockopt. * Also, desired default hop limit might be changed via * Neighbor Discovery. */ ip6->ip6_hlim = in6_selecthlim(inp, NULL); /* * Set the packet size here for the benefit of DTrace probes. * ip6_output() will set it properly; it's supposed to include * the option header lengths as well. */ ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(*ip6)); if (V_path_mtu_discovery && tp->t_maxseg > V_tcp_minmss) tp->t_flags2 |= TF2_PLPMTU_PMTUD; else tp->t_flags2 &= ~TF2_PLPMTU_PMTUD; if (tp->t_state == TCPS_SYN_SENT) TCP_PROBE5(connect__request, NULL, tp, ip6, tp, th); TCP_PROBE5(send, NULL, tp, ip6, tp, th); #ifdef TCPPCAP /* Save packet, if requested. */ tcp_pcap_add(th, m, &(tp->t_outpkts)); #endif /* TODO: IPv6 IP6TOS_ECT bit on */ error = ip6_output(m, inp->in6p_outputopts, &inp->inp_route6, ((so->so_options & SO_DONTROUTE) ? IP_ROUTETOIF : 0), NULL, NULL, inp); if (error == EMSGSIZE && inp->inp_route6.ro_nh != NULL) mtu = inp->inp_route6.ro_nh->nh_mtu; } #endif /* INET6 */ #if defined(INET) && defined(INET6) else #endif #ifdef INET { ip->ip_len = htons(m->m_pkthdr.len); #ifdef INET6 if (inp->inp_vflag & INP_IPV6PROTO) ip->ip_ttl = in6_selecthlim(inp, NULL); #endif /* INET6 */ /* * If we do path MTU discovery, then we set DF on every packet. * This might not be the best thing to do according to RFC3390 * Section 2. However the tcp hostcache migitates the problem * so it affects only the first tcp connection with a host. * * NB: Don't set DF on small MTU/MSS to have a safe fallback. */ if (V_path_mtu_discovery && tp->t_maxseg > V_tcp_minmss) { tp->t_flags2 |= TF2_PLPMTU_PMTUD; if (tp->t_port == 0 || len < V_tcp_minmss) { ip->ip_off |= htons(IP_DF); } } else { tp->t_flags2 &= ~TF2_PLPMTU_PMTUD; } if (tp->t_state == TCPS_SYN_SENT) TCP_PROBE5(connect__request, NULL, tp, ip, tp, th); TCP_PROBE5(send, NULL, tp, ip, tp, th); #ifdef TCPPCAP /* Save packet, if requested. */ tcp_pcap_add(th, m, &(tp->t_outpkts)); #endif error = ip_output(m, inp->inp_options, &inp->inp_route, ((so->so_options & SO_DONTROUTE) ? IP_ROUTETOIF : 0), 0, inp); if (error == EMSGSIZE && inp->inp_route.ro_nh != NULL) mtu = inp->inp_route.ro_nh->nh_mtu; } #endif /* INET */ if (lgb != NULL) { lgb->tlb_errno = error; lgb = NULL; } out: if (error == 0) tcp_account_for_send(tp, len, (tp->snd_nxt != tp->snd_max), 0, hw_tls); /* * In transmit state, time the transmission and arrange for * the retransmit. In persist state, just set snd_max. In a closed * state just return. */ if (flags & TH_RST) { TCPSTAT_INC(tcps_sndtotal); return (0); } else if ((tp->t_flags & TF_FORCEDATA) == 0 || !tcp_timer_active(tp, TT_PERSIST)) { tcp_seq startseq = tp->snd_nxt; /* * Advance snd_nxt over sequence space of this segment. */ if (flags & (TH_SYN|TH_FIN)) { if (flags & TH_SYN) tp->snd_nxt++; if (flags & TH_FIN) { tp->snd_nxt++; tp->t_flags |= TF_SENTFIN; } } if (sack_rxmit) goto timer; tp->snd_nxt += len; if (SEQ_GT(tp->snd_nxt, tp->snd_max)) { /* * Update "made progress" indication if we just * added new data to an empty socket buffer. */ if (tp->snd_una == tp->snd_max) tp->t_acktime = ticks; tp->snd_max = tp->snd_nxt; /* * Time this transmission if not a retransmission and * not currently timing anything. */ tp->t_sndtime = ticks; if (tp->t_rtttime == 0) { tp->t_rtttime = ticks; tp->t_rtseq = startseq; TCPSTAT_INC(tcps_segstimed); } #ifdef STATS if (!(tp->t_flags & TF_GPUTINPROG) && len) { tp->t_flags |= TF_GPUTINPROG; tp->gput_seq = startseq; tp->gput_ack = startseq + ulmin(sbavail(&so->so_snd) - off, sendwin); tp->gput_ts = tcp_ts_getticks(); } #endif /* STATS */ } /* * Set retransmit timer if not currently set, * and not doing a pure ack or a keep-alive probe. * Initial value for retransmit timer is smoothed * round-trip time + 2 * round-trip time variance. * Initialize shift counter which is used for backoff * of retransmit time. */ timer: if (!tcp_timer_active(tp, TT_REXMT) && ((sack_rxmit && tp->snd_nxt != tp->snd_max) || (tp->snd_nxt != tp->snd_una))) { if (tcp_timer_active(tp, TT_PERSIST)) { tcp_timer_activate(tp, TT_PERSIST, 0); tp->t_rxtshift = 0; } tcp_timer_activate(tp, TT_REXMT, TP_RXTCUR(tp)); } else if (len == 0 && sbavail(&so->so_snd) && !tcp_timer_active(tp, TT_REXMT) && !tcp_timer_active(tp, TT_PERSIST)) { /* * Avoid a situation where we do not set persist timer * after a zero window condition. For example: * 1) A -> B: packet with enough data to fill the window * 2) B -> A: ACK for #1 + new data (0 window * advertisement) * 3) A -> B: ACK for #2, 0 len packet * * In this case, A will not activate the persist timer, * because it chose to send a packet. Unless tcp_output * is called for some other reason (delayed ack timer, * another input packet from B, socket syscall), A will * not send zero window probes. * * So, if you send a 0-length packet, but there is data * in the socket buffer, and neither the rexmt or * persist timer is already set, then activate the * persist timer. */ tp->t_rxtshift = 0; tcp_setpersist(tp); } } else { /* * Persist case, update snd_max but since we are in * persist mode (no window) we do not update snd_nxt. */ int xlen = len; if (flags & TH_SYN) ++xlen; if (flags & TH_FIN) { ++xlen; tp->t_flags |= TF_SENTFIN; } if (SEQ_GT(tp->snd_nxt + xlen, tp->snd_max)) tp->snd_max = tp->snd_nxt + xlen; } if ((error == 0) && (tp->rcv_numsacks > 0) && TCPS_HAVEESTABLISHED(tp->t_state) && (tp->t_flags & TF_SACK_PERMIT)) { /* Clean up any DSACK's sent */ tcp_clean_dsack_blocks(tp); } if ((error == 0) && sack_rxmit && SEQ_LT(tp->snd_nxt, SEQ_MIN(p->rxmit, p->end))) { /* * When transmitting from SACK scoreboard * after an RTO, pull snd_nxt along. */ tp->snd_nxt = SEQ_MIN(p->rxmit, p->end); } if (error) { /* * We know that the packet was lost, so back out the * sequence number advance, if any. * * If the error is EPERM the packet got blocked by the * local firewall. Normally we should terminate the * connection but the blocking may have been spurious * due to a firewall reconfiguration cycle. So we treat * it like a packet loss and let the retransmit timer and * timeouts do their work over time. * XXX: It is a POLA question whether calling tcp_drop right * away would be the really correct behavior instead. */ if (((tp->t_flags & TF_FORCEDATA) == 0 || !tcp_timer_active(tp, TT_PERSIST)) && ((flags & TH_SYN) == 0) && (error != EPERM)) { if (sack_rxmit) { p->rxmit = SEQ_MIN(p->end, p->rxmit) - len; tp->sackhint.sack_bytes_rexmit -= len; KASSERT(tp->sackhint.sack_bytes_rexmit >= 0, ("sackhint bytes rtx >= 0")); KASSERT((flags & TH_FIN) == 0, ("error while FIN with SACK rxmit")); } else { tp->snd_nxt -= len; if (flags & TH_FIN) tp->snd_nxt--; } if (IN_RECOVERY(tp->t_flags)) tp->sackhint.prr_out -= len; } - SOCKBUF_UNLOCK_ASSERT(&so->so_snd); /* Check gotos. */ + SOCK_SENDBUF_UNLOCK_ASSERT(so); /* Check gotos. */ switch (error) { case EACCES: case EPERM: tp->t_softerror = error; return (error); case ENOBUFS: TCP_XMIT_TIMER_ASSERT(tp, len, flags); tp->snd_cwnd = tp->t_maxseg; return (0); case EMSGSIZE: /* * For some reason the interface we used initially * to send segments changed to another or lowered * its MTU. * If TSO was active we either got an interface * without TSO capabilits or TSO was turned off. * If we obtained mtu from ip_output() then update * it and try again. */ if (tso) tp->t_flags &= ~TF_TSO; if (mtu != 0) { tcp_mss_update(tp, -1, mtu, NULL, NULL); goto again; } return (error); case EHOSTDOWN: case EHOSTUNREACH: case ENETDOWN: case ENETUNREACH: if (TCPS_HAVERCVDSYN(tp->t_state)) { tp->t_softerror = error; return (0); } /* FALLTHROUGH */ default: return (error); } } TCPSTAT_INC(tcps_sndtotal); /* * Data sent (as far as we can tell). * If this advertises a larger window than any other segment, * then remember the size of the advertised window. * Any pending ACK has now been sent. */ if (SEQ_GT(tp->rcv_nxt + recwin, tp->rcv_adv)) tp->rcv_adv = tp->rcv_nxt + recwin; tp->last_ack_sent = tp->rcv_nxt; tp->t_flags &= ~(TF_ACKNOW | TF_DELACK); if (tcp_timer_active(tp, TT_DELACK)) tcp_timer_activate(tp, TT_DELACK, 0); if (sendalot) goto again; return (0); } void tcp_setpersist(struct tcpcb *tp) { int t = ((tp->t_srtt >> 2) + tp->t_rttvar) >> 1; int tt; int maxunacktime; tp->t_flags &= ~TF_PREVVALID; if (tcp_timer_active(tp, TT_REXMT)) panic("tcp_setpersist: retransmit pending"); /* * If the state is already closed, don't bother. */ if (tp->t_state == TCPS_CLOSED) return; /* * Start/restart persistence timer. */ TCPT_RANGESET(tt, t * tcp_backoff[tp->t_rxtshift], tcp_persmin, tcp_persmax); if (TP_MAXUNACKTIME(tp) && tp->t_acktime) { maxunacktime = tp->t_acktime + TP_MAXUNACKTIME(tp) - ticks; if (maxunacktime < 1) maxunacktime = 1; if (maxunacktime < tt) tt = maxunacktime; } tcp_timer_activate(tp, TT_PERSIST, tt); if (tp->t_rxtshift < V_tcp_retries) tp->t_rxtshift++; } /* * Insert TCP options according to the supplied parameters to the place * optp in a consistent way. Can handle unaligned destinations. * * The order of the option processing is crucial for optimal packing and * alignment for the scarce option space. * * The optimal order for a SYN/SYN-ACK segment is: * MSS (4) + NOP (1) + Window scale (3) + SACK permitted (2) + * Timestamp (10) + Signature (18) = 38 bytes out of a maximum of 40. * * The SACK options should be last. SACK blocks consume 8*n+2 bytes. * So a full size SACK blocks option is 34 bytes (with 4 SACK blocks). * At minimum we need 10 bytes (to generate 1 SACK block). If both * TCP Timestamps (12 bytes) and TCP Signatures (18 bytes) are present, * we only have 10 bytes for SACK options (40 - (12 + 18)). */ int tcp_addoptions(struct tcpopt *to, u_char *optp) { u_int32_t mask, optlen = 0; for (mask = 1; mask < TOF_MAXOPT; mask <<= 1) { if ((to->to_flags & mask) != mask) continue; if (optlen == TCP_MAXOLEN) break; switch (to->to_flags & mask) { case TOF_MSS: while (optlen % 4) { optlen += TCPOLEN_NOP; *optp++ = TCPOPT_NOP; } if (TCP_MAXOLEN - optlen < TCPOLEN_MAXSEG) continue; optlen += TCPOLEN_MAXSEG; *optp++ = TCPOPT_MAXSEG; *optp++ = TCPOLEN_MAXSEG; to->to_mss = htons(to->to_mss); bcopy((u_char *)&to->to_mss, optp, sizeof(to->to_mss)); optp += sizeof(to->to_mss); break; case TOF_SCALE: while (!optlen || optlen % 2 != 1) { optlen += TCPOLEN_NOP; *optp++ = TCPOPT_NOP; } if (TCP_MAXOLEN - optlen < TCPOLEN_WINDOW) continue; optlen += TCPOLEN_WINDOW; *optp++ = TCPOPT_WINDOW; *optp++ = TCPOLEN_WINDOW; *optp++ = to->to_wscale; break; case TOF_SACKPERM: while (optlen % 2) { optlen += TCPOLEN_NOP; *optp++ = TCPOPT_NOP; } if (TCP_MAXOLEN - optlen < TCPOLEN_SACK_PERMITTED) continue; optlen += TCPOLEN_SACK_PERMITTED; *optp++ = TCPOPT_SACK_PERMITTED; *optp++ = TCPOLEN_SACK_PERMITTED; break; case TOF_TS: while (!optlen || optlen % 4 != 2) { optlen += TCPOLEN_NOP; *optp++ = TCPOPT_NOP; } if (TCP_MAXOLEN - optlen < TCPOLEN_TIMESTAMP) continue; optlen += TCPOLEN_TIMESTAMP; *optp++ = TCPOPT_TIMESTAMP; *optp++ = TCPOLEN_TIMESTAMP; to->to_tsval = htonl(to->to_tsval); to->to_tsecr = htonl(to->to_tsecr); bcopy((u_char *)&to->to_tsval, optp, sizeof(to->to_tsval)); optp += sizeof(to->to_tsval); bcopy((u_char *)&to->to_tsecr, optp, sizeof(to->to_tsecr)); optp += sizeof(to->to_tsecr); break; case TOF_SIGNATURE: { int siglen = TCPOLEN_SIGNATURE - 2; while (!optlen || optlen % 4 != 2) { optlen += TCPOLEN_NOP; *optp++ = TCPOPT_NOP; } if (TCP_MAXOLEN - optlen < TCPOLEN_SIGNATURE) { to->to_flags &= ~TOF_SIGNATURE; continue; } optlen += TCPOLEN_SIGNATURE; *optp++ = TCPOPT_SIGNATURE; *optp++ = TCPOLEN_SIGNATURE; to->to_signature = optp; while (siglen--) *optp++ = 0; break; } case TOF_SACK: { int sackblks = 0; struct sackblk *sack = (struct sackblk *)to->to_sacks; tcp_seq sack_seq; while (!optlen || optlen % 4 != 2) { optlen += TCPOLEN_NOP; *optp++ = TCPOPT_NOP; } if (TCP_MAXOLEN - optlen < TCPOLEN_SACKHDR + TCPOLEN_SACK) continue; optlen += TCPOLEN_SACKHDR; *optp++ = TCPOPT_SACK; sackblks = min(to->to_nsacks, (TCP_MAXOLEN - optlen) / TCPOLEN_SACK); *optp++ = TCPOLEN_SACKHDR + sackblks * TCPOLEN_SACK; while (sackblks--) { sack_seq = htonl(sack->start); bcopy((u_char *)&sack_seq, optp, sizeof(sack_seq)); optp += sizeof(sack_seq); sack_seq = htonl(sack->end); bcopy((u_char *)&sack_seq, optp, sizeof(sack_seq)); optp += sizeof(sack_seq); optlen += TCPOLEN_SACK; sack++; } TCPSTAT_INC(tcps_sack_send_blocks); break; } case TOF_FASTOPEN: { int total_len; /* XXX is there any point to aligning this option? */ total_len = TCPOLEN_FAST_OPEN_EMPTY + to->to_tfo_len; if (TCP_MAXOLEN - optlen < total_len) { to->to_flags &= ~TOF_FASTOPEN; continue; } *optp++ = TCPOPT_FAST_OPEN; *optp++ = total_len; if (to->to_tfo_len > 0) { bcopy(to->to_tfo_cookie, optp, to->to_tfo_len); optp += to->to_tfo_len; } optlen += total_len; break; } default: panic("%s: unknown TCP option type", __func__); break; } } /* Terminate and pad TCP options to a 4 byte boundary. */ if (optlen % 4) { optlen += TCPOLEN_EOL; *optp++ = TCPOPT_EOL; } /* * According to RFC 793 (STD0007): * "The content of the header beyond the End-of-Option option * must be header padding (i.e., zero)." * and later: "The padding is composed of zeros." */ while (optlen % 4) { optlen += TCPOLEN_PAD; *optp++ = TCPOPT_PAD; } KASSERT(optlen <= TCP_MAXOLEN, ("%s: TCP options too long", __func__)); return (optlen); } /* * This is a copy of m_copym(), taking the TSO segment size/limit * constraints into account, and advancing the sndptr as it goes. */ struct mbuf * tcp_m_copym(struct mbuf *m, int32_t off0, int32_t *plen, int32_t seglimit, int32_t segsize, struct sockbuf *sb, bool hw_tls) { #ifdef KERN_TLS struct ktls_session *tls, *ntls; struct mbuf *start __diagused; #endif struct mbuf *n, **np; struct mbuf *top; int32_t off = off0; int32_t len = *plen; int32_t fragsize; int32_t len_cp = 0; int32_t *pkthdrlen; uint32_t mlen, frags; bool copyhdr; KASSERT(off >= 0, ("tcp_m_copym, negative off %d", off)); KASSERT(len >= 0, ("tcp_m_copym, negative len %d", len)); if (off == 0 && m->m_flags & M_PKTHDR) copyhdr = true; else copyhdr = false; while (off > 0) { KASSERT(m != NULL, ("tcp_m_copym, offset > size of mbuf chain")); if (off < m->m_len) break; off -= m->m_len; if ((sb) && (m == sb->sb_sndptr)) { sb->sb_sndptroff += m->m_len; sb->sb_sndptr = m->m_next; } m = m->m_next; } np = ⊤ top = NULL; pkthdrlen = NULL; #ifdef KERN_TLS if (hw_tls && (m->m_flags & M_EXTPG)) tls = m->m_epg_tls; else tls = NULL; start = m; #endif while (len > 0) { if (m == NULL) { KASSERT(len == M_COPYALL, ("tcp_m_copym, length > size of mbuf chain")); *plen = len_cp; if (pkthdrlen != NULL) *pkthdrlen = len_cp; break; } #ifdef KERN_TLS if (hw_tls) { if (m->m_flags & M_EXTPG) ntls = m->m_epg_tls; else ntls = NULL; /* * Avoid mixing TLS records with handshake * data or TLS records from different * sessions. */ if (tls != ntls) { MPASS(m != start); *plen = len_cp; if (pkthdrlen != NULL) *pkthdrlen = len_cp; break; } } #endif mlen = min(len, m->m_len - off); if (seglimit) { /* * For M_EXTPG mbufs, add 3 segments * + 1 in case we are crossing page boundaries * + 2 in case the TLS hdr/trailer are used * It is cheaper to just add the segments * than it is to take the cache miss to look * at the mbuf ext_pgs state in detail. */ if (m->m_flags & M_EXTPG) { fragsize = min(segsize, PAGE_SIZE); frags = 3; } else { fragsize = segsize; frags = 0; } /* Break if we really can't fit anymore. */ if ((frags + 1) >= seglimit) { *plen = len_cp; if (pkthdrlen != NULL) *pkthdrlen = len_cp; break; } /* * Reduce size if you can't copy the whole * mbuf. If we can't copy the whole mbuf, also * adjust len so the loop will end after this * mbuf. */ if ((frags + howmany(mlen, fragsize)) >= seglimit) { mlen = (seglimit - frags - 1) * fragsize; len = mlen; *plen = len_cp + len; if (pkthdrlen != NULL) *pkthdrlen = *plen; } frags += howmany(mlen, fragsize); if (frags == 0) frags++; seglimit -= frags; KASSERT(seglimit > 0, ("%s: seglimit went too low", __func__)); } if (copyhdr) n = m_gethdr(M_NOWAIT, m->m_type); else n = m_get(M_NOWAIT, m->m_type); *np = n; if (n == NULL) goto nospace; if (copyhdr) { if (!m_dup_pkthdr(n, m, M_NOWAIT)) goto nospace; if (len == M_COPYALL) n->m_pkthdr.len -= off0; else n->m_pkthdr.len = len; pkthdrlen = &n->m_pkthdr.len; copyhdr = false; } n->m_len = mlen; len_cp += n->m_len; if (m->m_flags & (M_EXT | M_EXTPG)) { n->m_data = m->m_data + off; mb_dupcl(n, m); } else bcopy(mtod(m, caddr_t)+off, mtod(n, caddr_t), (u_int)n->m_len); if (sb && (sb->sb_sndptr == m) && ((n->m_len + off) >= m->m_len) && m->m_next) { sb->sb_sndptroff += m->m_len; sb->sb_sndptr = m->m_next; } off = 0; if (len != M_COPYALL) { len -= n->m_len; } m = m->m_next; np = &n->m_next; } return (top); nospace: m_freem(top); return (NULL); } void tcp_sndbuf_autoscale(struct tcpcb *tp, struct socket *so, uint32_t sendwin) { /* * Automatic sizing of send socket buffer. Often the send buffer * size is not optimally adjusted to the actual network conditions * at hand (delay bandwidth product). Setting the buffer size too * small limits throughput on links with high bandwidth and high * delay (eg. trans-continental/oceanic links). Setting the * buffer size too big consumes too much real kernel memory, * especially with many connections on busy servers. * * The criteria to step up the send buffer one notch are: * 1. receive window of remote host is larger than send buffer * (with a fudge factor of 5/4th); * 2. send buffer is filled to 7/8th with data (so we actually * have data to make use of it); * 3. send buffer fill has not hit maximal automatic size; * 4. our send window (slow start and cogestion controlled) is * larger than sent but unacknowledged data in send buffer. * * The remote host receive window scaling factor may limit the * growing of the send buffer before it reaches its allowed * maximum. * * It scales directly with slow start or congestion window * and does at most one step per received ACK. This fast * scaling has the drawback of growing the send buffer beyond * what is strictly necessary to make full use of a given * delay*bandwidth product. However testing has shown this not * to be much of an problem. At worst we are trading wasting * of available bandwidth (the non-use of it) for wasting some * socket buffer memory. * * TODO: Shrink send buffer during idle periods together * with congestion window. Requires another timer. Has to * wait for upcoming tcp timer rewrite. * * XXXGL: should there be used sbused() or sbavail()? */ if (V_tcp_do_autosndbuf && so->so_snd.sb_flags & SB_AUTOSIZE) { int lowat; lowat = V_tcp_sendbuf_auto_lowat ? so->so_snd.sb_lowat : 0; if ((tp->snd_wnd / 4 * 5) >= so->so_snd.sb_hiwat - lowat && sbused(&so->so_snd) >= (so->so_snd.sb_hiwat / 8 * 7) - lowat && sbused(&so->so_snd) < V_tcp_autosndbuf_max && sendwin >= (sbused(&so->so_snd) - (tp->snd_nxt - tp->snd_una))) { if (!sbreserve_locked(so, SO_SND, min(so->so_snd.sb_hiwat + V_tcp_autosndbuf_inc, V_tcp_autosndbuf_max), curthread)) so->so_snd.sb_flags &= ~SB_AUTOSIZE; } } } diff --git a/sys/netinet/tcp_reass.c b/sys/netinet/tcp_reass.c index 5768d90a9337..5f73e83dc8a9 100644 --- a/sys/netinet/tcp_reass.c +++ b/sys/netinet/tcp_reass.c @@ -1,1115 +1,1115 @@ /*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1994, 1995 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include #include "opt_inet.h" #include "opt_inet6.h" /* For debugging we want counters and BB logging */ /* #define TCP_REASS_COUNTERS 1 */ /* #define TCP_REASS_LOGGING 1 */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef TCP_REASS_LOGGING #include #include #endif #include #define TCP_R_LOG_ADD 1 #define TCP_R_LOG_LIMIT_REACHED 2 #define TCP_R_LOG_APPEND 3 #define TCP_R_LOG_PREPEND 4 #define TCP_R_LOG_REPLACE 5 #define TCP_R_LOG_MERGE_INTO 6 #define TCP_R_LOG_NEW_ENTRY 7 #define TCP_R_LOG_READ 8 #define TCP_R_LOG_ZERO 9 #define TCP_R_LOG_DUMP 10 #define TCP_R_LOG_TRIM 11 static SYSCTL_NODE(_net_inet_tcp, OID_AUTO, reass, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, "TCP Segment Reassembly Queue"); static SYSCTL_NODE(_net_inet_tcp_reass, OID_AUTO, stats, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, "TCP Segment Reassembly stats"); static int tcp_reass_maxseg = 0; SYSCTL_INT(_net_inet_tcp_reass, OID_AUTO, maxsegments, CTLFLAG_RDTUN, &tcp_reass_maxseg, 0, "Global maximum number of TCP Segments in Reassembly Queue"); static uma_zone_t tcp_reass_zone; SYSCTL_UMA_CUR(_net_inet_tcp_reass, OID_AUTO, cursegments, 0, &tcp_reass_zone, "Global number of TCP Segments currently in Reassembly Queue"); static u_int tcp_reass_maxqueuelen = 100; SYSCTL_UINT(_net_inet_tcp_reass, OID_AUTO, maxqueuelen, CTLFLAG_RWTUN, &tcp_reass_maxqueuelen, 0, "Maximum number of TCP Segments per Reassembly Queue"); static int tcp_new_limits = 0; SYSCTL_INT(_net_inet_tcp_reass, OID_AUTO, new_limit, CTLFLAG_RWTUN, &tcp_new_limits, 0, "Do we use the new limit method we are discussing?"); static u_int tcp_reass_queue_guard = 16; SYSCTL_UINT(_net_inet_tcp_reass, OID_AUTO, queueguard, CTLFLAG_RWTUN, &tcp_reass_queue_guard, 16, "Number of TCP Segments in Reassembly Queue where we flip over to guard mode"); #ifdef TCP_REASS_COUNTERS counter_u64_t reass_entry; SYSCTL_COUNTER_U64(_net_inet_tcp_reass_stats, OID_AUTO, entry, CTLFLAG_RD, &reass_entry, "A segment entered reassembly "); counter_u64_t reass_path1; SYSCTL_COUNTER_U64(_net_inet_tcp_reass_stats, OID_AUTO, path1, CTLFLAG_RD, &reass_path1, "Took path 1"); counter_u64_t reass_path2; SYSCTL_COUNTER_U64(_net_inet_tcp_reass_stats, OID_AUTO, path2, CTLFLAG_RD, &reass_path2, "Took path 2"); counter_u64_t reass_path3; SYSCTL_COUNTER_U64(_net_inet_tcp_reass_stats, OID_AUTO, path3, CTLFLAG_RD, &reass_path3, "Took path 3"); counter_u64_t reass_path4; SYSCTL_COUNTER_U64(_net_inet_tcp_reass_stats, OID_AUTO, path4, CTLFLAG_RD, &reass_path4, "Took path 4"); counter_u64_t reass_path5; SYSCTL_COUNTER_U64(_net_inet_tcp_reass_stats, OID_AUTO, path5, CTLFLAG_RD, &reass_path5, "Took path 5"); counter_u64_t reass_path6; SYSCTL_COUNTER_U64(_net_inet_tcp_reass_stats, OID_AUTO, path6, CTLFLAG_RD, &reass_path6, "Took path 6"); counter_u64_t reass_path7; SYSCTL_COUNTER_U64(_net_inet_tcp_reass_stats, OID_AUTO, path7, CTLFLAG_RD, &reass_path7, "Took path 7"); counter_u64_t reass_fullwalk; SYSCTL_COUNTER_U64(_net_inet_tcp_reass_stats, OID_AUTO, fullwalk, CTLFLAG_RD, &reass_fullwalk, "Took a full walk "); counter_u64_t reass_nospace; SYSCTL_COUNTER_U64(_net_inet_tcp_reass_stats, OID_AUTO, nospace, CTLFLAG_RD, &reass_nospace, "Had no mbuf capacity "); counter_u64_t merge_fwd; SYSCTL_COUNTER_U64(_net_inet_tcp_reass_stats, OID_AUTO, merge_fwd, CTLFLAG_RD, &merge_fwd, "Ran merge fwd"); counter_u64_t merge_into; SYSCTL_COUNTER_U64(_net_inet_tcp_reass_stats, OID_AUTO, merge_into, CTLFLAG_RD, &merge_into, "Ran merge into"); counter_u64_t tcp_zero_input; SYSCTL_COUNTER_U64(_net_inet_tcp_reass_stats, OID_AUTO, zero_input, CTLFLAG_RD, &tcp_zero_input, "The reassembly buffer saw a zero len segment etc"); #endif /* Initialize TCP reassembly queue */ static void tcp_reass_zone_change(void *tag) { /* Set the zone limit and read back the effective value. */ tcp_reass_maxseg = nmbclusters / 16; tcp_reass_maxseg = uma_zone_set_max(tcp_reass_zone, tcp_reass_maxseg); } #ifdef TCP_REASS_LOGGING static void tcp_log_reassm(struct tcpcb *tp, struct tseg_qent *q, struct tseg_qent *p, tcp_seq seq, int len, uint8_t action, int instance) { struct socket *so = tptosocket(tp); uint32_t cts; struct timeval tv; if (tp->t_logstate != TCP_LOG_STATE_OFF) { union tcp_log_stackspecific log; memset(&log, 0, sizeof(log)); cts = tcp_get_usecs(&tv); log.u_bbr.flex1 = seq; log.u_bbr.cur_del_rate = (uint64_t)q; log.u_bbr.delRate = (uint64_t)p; if (q != NULL) { log.u_bbr.flex2 = q->tqe_start; log.u_bbr.flex3 = q->tqe_len; log.u_bbr.flex4 = q->tqe_mbuf_cnt; log.u_bbr.hptsi_gain = q->tqe_flags; } if (p != NULL) { log.u_bbr.flex5 = p->tqe_start; log.u_bbr.pkts_out = p->tqe_len; log.u_bbr.epoch = p->tqe_mbuf_cnt; log.u_bbr.cwnd_gain = p->tqe_flags; } log.u_bbr.flex6 = tp->t_segqmbuflen; log.u_bbr.flex7 = instance; log.u_bbr.flex8 = action; log.u_bbr.timeStamp = cts; TCP_LOG_EVENTP(tp, NULL, &so->so_rcv, &so->so_snd, TCP_LOG_REASS, 0, len, &log, false, &tv); } } static void tcp_reass_log_dump(struct tcpcb *tp) { struct tseg_qent *q; if (tp->t_logstate != TCP_LOG_STATE_OFF) { TAILQ_FOREACH(q, &tp->t_segq, tqe_q) { tcp_log_reassm(tp, q, NULL, q->tqe_start, q->tqe_len, TCP_R_LOG_DUMP, 0); } }; } static void tcp_reass_log_new_in(struct tcpcb *tp, tcp_seq seq, int len, struct mbuf *m, int logval, struct tseg_qent *q) { int cnt; struct mbuf *t; cnt = 0; t = m; while (t) { cnt += t->m_len; t = t->m_next; } tcp_log_reassm(tp, q, NULL, seq, len, logval, cnt); } #endif void tcp_reass_global_init(void) { tcp_reass_maxseg = nmbclusters / 16; TUNABLE_INT_FETCH("net.inet.tcp.reass.maxsegments", &tcp_reass_maxseg); tcp_reass_zone = uma_zcreate("tcpreass", sizeof (struct tseg_qent), NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); /* Set the zone limit and read back the effective value. */ tcp_reass_maxseg = uma_zone_set_max(tcp_reass_zone, tcp_reass_maxseg); #ifdef TCP_REASS_COUNTERS reass_path1 = counter_u64_alloc(M_WAITOK); reass_path2 = counter_u64_alloc(M_WAITOK); reass_path3 = counter_u64_alloc(M_WAITOK); reass_path4 = counter_u64_alloc(M_WAITOK); reass_path5 = counter_u64_alloc(M_WAITOK); reass_path6 = counter_u64_alloc(M_WAITOK); reass_path7 = counter_u64_alloc(M_WAITOK); reass_fullwalk = counter_u64_alloc(M_WAITOK); reass_nospace = counter_u64_alloc(M_WAITOK); reass_entry = counter_u64_alloc(M_WAITOK); merge_fwd = counter_u64_alloc(M_WAITOK); merge_into = counter_u64_alloc(M_WAITOK); tcp_zero_input = counter_u64_alloc(M_WAITOK); #endif EVENTHANDLER_REGISTER(nmbclusters_change, tcp_reass_zone_change, NULL, EVENTHANDLER_PRI_ANY); } void tcp_reass_flush(struct tcpcb *tp) { struct tseg_qent *qe; INP_WLOCK_ASSERT(tptoinpcb(tp)); while ((qe = TAILQ_FIRST(&tp->t_segq)) != NULL) { TAILQ_REMOVE(&tp->t_segq, qe, tqe_q); m_freem(qe->tqe_m); uma_zfree(tcp_reass_zone, qe); tp->t_segqlen--; } tp->t_segqmbuflen = 0; KASSERT((tp->t_segqlen == 0), ("TCP reass queue %p segment count is %d instead of 0 after flush.", tp, tp->t_segqlen)); } static void tcp_reass_append(struct tcpcb *tp, struct tseg_qent *last, struct mbuf *m, struct tcphdr *th, int tlen, struct mbuf *mlast, int lenofoh) { #ifdef TCP_REASS_LOGGING tcp_log_reassm(tp, last, NULL, th->th_seq, tlen, TCP_R_LOG_APPEND, 0); #endif last->tqe_len += tlen; last->tqe_m->m_pkthdr.len += tlen; /* Preserve the FIN bit if its there */ last->tqe_flags |= (tcp_get_flags(th) & TH_FIN); last->tqe_last->m_next = m; last->tqe_last = mlast; last->tqe_mbuf_cnt += lenofoh; tp->t_rcvoopack++; TCPSTAT_INC(tcps_rcvoopack); TCPSTAT_ADD(tcps_rcvoobyte, tlen); #ifdef TCP_REASS_LOGGING tcp_reass_log_new_in(tp, last->tqe_start, lenofoh, last->tqe_m, TCP_R_LOG_APPEND, last); #endif } static void tcp_reass_prepend(struct tcpcb *tp, struct tseg_qent *first, struct mbuf *m, struct tcphdr *th, int tlen, struct mbuf *mlast, int lenofoh) { int i; #ifdef TCP_REASS_LOGGING tcp_log_reassm(tp, first, NULL, th->th_seq, tlen, TCP_R_LOG_PREPEND, 0); #endif if (SEQ_GT((th->th_seq + tlen), first->tqe_start)) { /* The new data overlaps into the old */ i = (th->th_seq + tlen) - first->tqe_start; #ifdef TCP_REASS_LOGGING tcp_log_reassm(tp, first, NULL, 0, i, TCP_R_LOG_TRIM, 1); #endif m_adj(first->tqe_m, i); first->tqe_len -= i; first->tqe_start += i; } /* Ok now setup our chain to point to the old first */ mlast->m_next = first->tqe_m; first->tqe_m = m; first->tqe_len += tlen; first->tqe_start = th->th_seq; first->tqe_m->m_pkthdr.len = first->tqe_len; first->tqe_mbuf_cnt += lenofoh; tp->t_rcvoopack++; TCPSTAT_INC(tcps_rcvoopack); TCPSTAT_ADD(tcps_rcvoobyte, tlen); #ifdef TCP_REASS_LOGGING tcp_reass_log_new_in(tp, first->tqe_start, lenofoh, first->tqe_m, TCP_R_LOG_PREPEND, first); #endif } static void tcp_reass_replace(struct tcpcb *tp, struct tseg_qent *q, struct mbuf *m, tcp_seq seq, int len, struct mbuf *mlast, int mbufoh, uint16_t flags) { /* * Free the data in q, and replace * it with the new segment. */ int len_dif; #ifdef TCP_REASS_LOGGING tcp_log_reassm(tp, q, NULL, seq, len, TCP_R_LOG_REPLACE, 0); #endif m_freem(q->tqe_m); KASSERT(tp->t_segqmbuflen >= q->tqe_mbuf_cnt, ("Tp:%p seg queue goes negative", tp)); tp->t_segqmbuflen -= q->tqe_mbuf_cnt; q->tqe_mbuf_cnt = mbufoh; q->tqe_m = m; q->tqe_last = mlast; q->tqe_start = seq; if (len > q->tqe_len) len_dif = len - q->tqe_len; else len_dif = 0; tp->t_rcvoopack++; TCPSTAT_INC(tcps_rcvoopack); TCPSTAT_ADD(tcps_rcvoobyte, len_dif); q->tqe_len = len; q->tqe_flags = (flags & TH_FIN); q->tqe_m->m_pkthdr.len = q->tqe_len; tp->t_segqmbuflen += mbufoh; } static void tcp_reass_merge_into(struct tcpcb *tp, struct tseg_qent *ent, struct tseg_qent *q) { /* * Merge q into ent and free q from the list. */ #ifdef TCP_REASS_LOGGING tcp_log_reassm(tp, q, ent, 0, 0, TCP_R_LOG_MERGE_INTO, 0); #endif #ifdef TCP_REASS_COUNTERS counter_u64_add(merge_into, 1); #endif ent->tqe_last->m_next = q->tqe_m; ent->tqe_last = q->tqe_last; ent->tqe_len += q->tqe_len; ent->tqe_mbuf_cnt += q->tqe_mbuf_cnt; ent->tqe_m->m_pkthdr.len += q->tqe_len; ent->tqe_flags |= (q->tqe_flags & TH_FIN); TAILQ_REMOVE(&tp->t_segq, q, tqe_q); uma_zfree(tcp_reass_zone, q); tp->t_segqlen--; } static void tcp_reass_merge_forward(struct tcpcb *tp, struct tseg_qent *ent) { struct tseg_qent *q, *qtmp; int i; tcp_seq max; /* * Given an entry merge forward anyplace * that ent overlaps forward. */ max = ent->tqe_start + ent->tqe_len; q = TAILQ_NEXT(ent, tqe_q); if (q == NULL) { /* Nothing left */ return; } TAILQ_FOREACH_FROM_SAFE(q, &tp->t_segq, tqe_q, qtmp) { if (SEQ_GT(q->tqe_start, max)) { /* Beyond q */ break; } /* We have some or all that are overlapping */ if (SEQ_GEQ(max, (q->tqe_start + q->tqe_len))) { /* It consumes it all */ tp->t_segqmbuflen -= q->tqe_mbuf_cnt; m_freem(q->tqe_m); TAILQ_REMOVE(&tp->t_segq, q, tqe_q); uma_zfree(tcp_reass_zone, q); tp->t_segqlen--; continue; } /* * Trim the q entry to dovetail to this one * and then merge q into ent updating max * in the process. */ i = max - q->tqe_start; #ifdef TCP_REASS_LOGGING tcp_log_reassm(tp, q, NULL, 0, i, TCP_R_LOG_TRIM, 2); #endif m_adj(q->tqe_m, i); q->tqe_len -= i; q->tqe_start += i; tcp_reass_merge_into(tp, ent, q); max = ent->tqe_start + ent->tqe_len; } #ifdef TCP_REASS_COUNTERS counter_u64_add(merge_fwd, 1); #endif } static int tcp_reass_overhead_of_chain(struct mbuf *m, struct mbuf **mlast) { int len = MSIZE; if (m->m_flags & M_EXT) len += m->m_ext.ext_size; while (m->m_next != NULL) { m = m->m_next; len += MSIZE; if (m->m_flags & M_EXT) len += m->m_ext.ext_size; } *mlast = m; return (len); } /* * NOTE!!! the new tcp-reassembly code *must not* use * m_adj() with a negative index. That alters the chain * of mbufs (by possibly chopping trailing mbufs). At * the front of tcp_reass we count the mbuf overhead * and setup the tail pointer. If we use m_adj(m, -5) * we could corrupt the tail pointer. Currently the * code only uses m_adj(m, postive-num). If this * changes appropriate changes to update mlast would * be needed. */ int tcp_reass(struct tcpcb *tp, struct tcphdr *th, tcp_seq *seq_start, int *tlenp, struct mbuf *m) { struct tseg_qent *q, *last, *first; struct tseg_qent *p = NULL; struct tseg_qent *nq = NULL; struct tseg_qent *te = NULL; struct mbuf *mlast = NULL; struct inpcb *inp = tptoinpcb(tp); struct socket *so = tptosocket(tp); struct sockbuf *sb = &so->so_rcv; char *s = NULL; int flags, i, lenofoh; INP_WLOCK_ASSERT(inp); /* * XXX: tcp_reass() is rather inefficient with its data structures * and should be rewritten (see NetBSD for optimizations). */ KASSERT(th == NULL || (seq_start != NULL && tlenp != NULL), ("tcp_reass called with illegal parameter combination " "(tp=%p, th=%p, seq_start=%p, tlenp=%p, m=%p)", tp, th, seq_start, tlenp, m)); /* * Call with th==NULL after become established to * force pre-ESTABLISHED data up to user socket. */ if (th == NULL) goto present; KASSERT(SEQ_GEQ(th->th_seq, tp->rcv_nxt), ("Attempt to add old entry to reassembly queue (th=%p, tp=%p)", th, tp)); #ifdef TCP_REASS_LOGGING tcp_reass_log_new_in(tp, th->th_seq, *tlenp, m, TCP_R_LOG_ADD, NULL); #endif #ifdef TCP_REASS_COUNTERS counter_u64_add(reass_entry, 1); #endif /* * Check for zero length data. */ if ((*tlenp == 0) && ((tcp_get_flags(th) & TH_FIN) == 0)) { /* * A zero length segment does no * one any good. We could check * the rcv_nxt <-> rcv_wnd but thats * already done for us by the caller. */ strip_fin: #ifdef TCP_REASS_COUNTERS counter_u64_add(tcp_zero_input, 1); #endif m_freem(m); #ifdef TCP_REASS_LOGGING tcp_reass_log_dump(tp); #endif return (0); } else if ((*tlenp == 0) && (tcp_get_flags(th) & TH_FIN) && !TCPS_HAVEESTABLISHED(tp->t_state)) { /* * We have not established, and we * have a FIN and no data. Lets treat * this as the same as if the FIN were * not present. We don't want to save * the FIN bit in a reassembly buffer * we want to get established first before * we do that (the peer will retransmit). */ goto strip_fin; } /* * Will it fit? */ lenofoh = tcp_reass_overhead_of_chain(m, &mlast); if ((th->th_seq != tp->rcv_nxt || !TCPS_HAVEESTABLISHED(tp->t_state)) && (sb->sb_mbcnt + tp->t_segqmbuflen + lenofoh) > sb->sb_mbmax) { /* No room */ TCPSTAT_INC(tcps_rcvreassfull); #ifdef TCP_REASS_COUNTERS counter_u64_add(reass_nospace, 1); #endif #ifdef TCP_REASS_LOGGING tcp_log_reassm(tp, NULL, NULL, th->th_seq, lenofoh, TCP_R_LOG_LIMIT_REACHED, 0); #endif if ((s = tcp_log_addrs(&inp->inp_inc, th, NULL, NULL))) { log(LOG_DEBUG, "%s; %s: mbuf count limit reached, " "segment dropped\n", s, __func__); free(s, M_TCPLOG); } m_freem(m); *tlenp = 0; #ifdef TCP_REASS_LOGGING tcp_reass_log_dump(tp); #endif return (0); } /* * First lets deal with two common cases, the * segment appends to the back of our collected * segments. Or the segment is the next in line. */ last = TAILQ_LAST_FAST(&tp->t_segq, tseg_qent, tqe_q); if (last != NULL) { if ((tcp_get_flags(th) & TH_FIN) && SEQ_LT((th->th_seq + *tlenp), (last->tqe_start + last->tqe_len))) { /* * Someone is trying to game us, dump * the segment. */ *tlenp = 0; m_freem(m); return (0); } if ((SEQ_GEQ(th->th_seq, last->tqe_start)) && (SEQ_GEQ((last->tqe_start + last->tqe_len), th->th_seq))) { /* Common case, trailing segment is added */ /** * +--last * v * reassembly buffer |---| |---| |---| * new segment |---| */ #ifdef TCP_REASS_COUNTERS counter_u64_add(reass_path1, 1); #endif if (SEQ_GT((last->tqe_start + last->tqe_len), th->th_seq)) { i = (last->tqe_start + last->tqe_len) - th->th_seq; if (i < *tlenp) { #ifdef TCP_REASS_LOGGING tcp_log_reassm(tp, last, NULL, 0, i, TCP_R_LOG_TRIM, 3); th->th_seq += i; #endif m_adj(m, i); *tlenp -= i; } else { /* Complete overlap */ TCPSTAT_INC(tcps_rcvduppack); TCPSTAT_ADD(tcps_rcvdupbyte, *tlenp); m_freem(m); *tlenp = last->tqe_len; *seq_start = last->tqe_start; return (0); } } if (last->tqe_flags & TH_FIN) { /* * We have data after the FIN on the last? */ *tlenp = 0; m_freem(m); return(0); } tcp_reass_append(tp, last, m, th, *tlenp, mlast, lenofoh); tp->t_segqmbuflen += lenofoh; *seq_start = last->tqe_start; *tlenp = last->tqe_len; return (0); } else if (SEQ_GT(th->th_seq, (last->tqe_start + last->tqe_len))) { /* * Second common case, we missed * another one and have something more * for the end. */ /** * +--last * v * reassembly buffer |---| |---| |---| * new segment |---| */ if (last->tqe_flags & TH_FIN) { /* * We have data after the FIN on the last? */ *tlenp = 0; m_freem(m); return(0); } #ifdef TCP_REASS_COUNTERS counter_u64_add(reass_path2, 1); #endif p = last; goto new_entry; } } else { /* First segment (it's NULL). */ goto new_entry; } first = TAILQ_FIRST(&tp->t_segq); if (SEQ_LT(th->th_seq, first->tqe_start) && SEQ_GEQ((th->th_seq + *tlenp),first->tqe_start) && SEQ_LT((th->th_seq + *tlenp), (first->tqe_start + first->tqe_len))) { /* * The head of the queue is prepended by this and * it may be the one I want most. */ /** * first-------+ * v * rea: |---| |---| |---| * new: |---| * Note the case we do not deal with here is: * rea= |---| |---| |---| * new= |----| * Due to the fact that it could be * new |--------------------| * And we might need to merge forward. */ #ifdef INVARIANTS struct mbuf *firstmbuf; #endif #ifdef TCP_REASS_COUNTERS counter_u64_add(reass_path3, 1); #endif if (SEQ_LT(th->th_seq, tp->rcv_nxt)) { /* * The resend was even before * what we have. We need to trim it. * Note TSNH (it should be trimmed * before the call to tcp_reass()). */ #ifdef INVARIANTS panic("th->th_seq:%u rcv_nxt:%u tp:%p not pre-trimmed", th->th_seq, tp->rcv_nxt, tp); #else i = tp->rcv_nxt - th->th_seq; #ifdef TCP_REASS_LOGGING tcp_log_reassm(tp, first, NULL, 0, i, TCP_R_LOG_TRIM, 4); #endif m_adj(m, i); th->th_seq += i; *tlenp -= i; #endif } #ifdef INVARIANTS firstmbuf = first->tqe_m; #endif tcp_reass_prepend(tp, first, m, th, *tlenp, mlast, lenofoh); #ifdef INVARIANTS if (firstmbuf == first->tqe_m) { panic("First stayed same m:%p foobar:%p first->tqe_m:%p tp:%p first:%p", m, firstmbuf, first->tqe_m, tp, first); } else if (first->tqe_m != m) { panic("First did not change to m:%p foobar:%p first->tqe_m:%p tp:%p first:%p", m, firstmbuf, first->tqe_m, tp, first); } #endif tp->t_segqmbuflen += lenofoh; *seq_start = first->tqe_start; *tlenp = first->tqe_len; goto present; } else if (SEQ_LT((th->th_seq + *tlenp), first->tqe_start)) { /* New segment is before our earliest segment. */ /** * first---->+ * v * rea= |---| .... * new" |---| * */ goto new_entry; } /* * Find a segment which begins after this one does. */ #ifdef TCP_REASS_COUNTERS counter_u64_add(reass_fullwalk, 1); #endif TAILQ_FOREACH(q, &tp->t_segq, tqe_q) { if (SEQ_GT(q->tqe_start, th->th_seq)) break; } p = TAILQ_PREV(q, tsegqe_head, tqe_q); /** * Now is this fit just in-between only? * i.e.: * p---+ +----q * v v * res= |--| |--| |--| * nee |-| */ if (SEQ_LT((th->th_seq + *tlenp), q->tqe_start) && ((p == NULL) || (SEQ_GT(th->th_seq, (p->tqe_start + p->tqe_len))))) { /* Yep no overlap */ goto new_entry; } /** * If we reach here we have some (possibly all) overlap * such as: * res= |--| |--| |--| * new= |----| * or new= |-----------------| * or new= |--------| * or new= |---| * or new= |-----------| */ if ((p != NULL) && (SEQ_LEQ(th->th_seq, (p->tqe_start + p->tqe_len)))) { /* conversion to int (in i) handles seq wraparound */ #ifdef TCP_REASS_COUNTERS counter_u64_add(reass_path4, 1); #endif i = p->tqe_start + p->tqe_len - th->th_seq; if (i >= 0) { if (i >= *tlenp) { /** * prev seg---->+ * v * reassembly buffer |---| * new segment |-| */ TCPSTAT_INC(tcps_rcvduppack); TCPSTAT_ADD(tcps_rcvdupbyte, *tlenp); *tlenp = p->tqe_len; *seq_start = p->tqe_start; m_freem(m); /* * Try to present any queued data * at the left window edge to the user. * This is needed after the 3-WHS * completes. Note this probably * will not work and we will return. */ return (0); } if (i > 0) { /** * prev seg---->+ * v * reassembly buffer |---| * new segment |-----| */ #ifdef TCP_REASS_COUNTERS counter_u64_add(reass_path5, 1); #endif #ifdef TCP_REASS_LOGGING tcp_log_reassm(tp, p, NULL, 0, i, TCP_R_LOG_TRIM, 5); #endif m_adj(m, i); *tlenp -= i; th->th_seq += i; } } if (th->th_seq == (p->tqe_start + p->tqe_len)) { /* * If dovetails in with this one * append it. */ /** * prev seg---->+ * v * reassembly buffer |--| |---| * new segment |--| * (note: it was trimmed above if it overlapped) */ tcp_reass_append(tp, p, m, th, *tlenp, mlast, lenofoh); tp->t_segqmbuflen += lenofoh; } else { #ifdef INVARIANTS panic("Impossible cut th_seq:%u p->seq:%u(%d) p:%p tp:%p", th->th_seq, p->tqe_start, p->tqe_len, p, tp); #endif *tlenp = 0; m_freem(m); return (0); } q = p; } else { /* * The new data runs over the * top of previously sack'd data (in q). * It may be partially overlapping, or * it may overlap the entire segment. */ #ifdef TCP_REASS_COUNTERS counter_u64_add(reass_path6, 1); #endif if (SEQ_GEQ((th->th_seq + *tlenp), (q->tqe_start + q->tqe_len))) { /* It consumes it all */ /** * next seg---->+ * v * reassembly buffer |--| |---| * new segment |----------| */ #ifdef TCP_REASS_COUNTERS counter_u64_add(reass_path7, 1); #endif tcp_reass_replace(tp, q, m, th->th_seq, *tlenp, mlast, lenofoh, tcp_get_flags(th)); } else { /* * We just need to prepend the data * to this. It does not overrun * the end. */ /** * next seg---->+ * v * reassembly buffer |--| |---| * new segment |----------| */ tcp_reass_prepend(tp, q, m, th, *tlenp, mlast, lenofoh); tp->t_segqmbuflen += lenofoh; } } /* Now does it go further than that? */ tcp_reass_merge_forward(tp, q); *seq_start = q->tqe_start; *tlenp = q->tqe_len; goto present; /* * When we reach here we can't combine it * with any existing segment. * * Limit the number of segments that can be queued to reduce the * potential for mbuf exhaustion. For best performance, we want to be * able to queue a full window's worth of segments. The size of the * socket receive buffer determines our advertised window and grows * automatically when socket buffer autotuning is enabled. Use it as the * basis for our queue limit. * * However, allow the user to specify a ceiling for the number of * segments in each queue. * * Always let the missing segment through which caused this queue. * NB: Access to the socket buffer is left intentionally unlocked as we * can tolerate stale information here. * * XXXLAS: Using sbspace(so->so_rcv) instead of so->so_rcv.sb_hiwat * should work but causes packets to be dropped when they shouldn't. * Investigate why and re-evaluate the below limit after the behaviour * is understood. */ new_entry: if (th->th_seq == tp->rcv_nxt && TCPS_HAVEESTABLISHED(tp->t_state)) { tp->rcv_nxt += *tlenp; flags = tcp_get_flags(th) & TH_FIN; TCPSTAT_INC(tcps_rcvoopack); TCPSTAT_ADD(tcps_rcvoobyte, *tlenp); - SOCKBUF_LOCK(&so->so_rcv); + SOCK_RECVBUF_LOCK(so); if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { m_freem(m); } else { sbappendstream_locked(&so->so_rcv, m, 0); } tp->t_flags |= TF_WAKESOR; return (flags); } if (tcp_new_limits) { if ((tp->t_segqlen > tcp_reass_queue_guard) && (*tlenp < MSIZE)) { /* * This is really a lie, we are not full but * are getting a segment that is above * guard threshold. If it is and its below * a mbuf size (256) we drop it if it * can't fill in some place. */ TCPSTAT_INC(tcps_rcvreassfull); *tlenp = 0; if ((s = tcp_log_addrs(&inp->inp_inc, th, NULL, NULL))) { log(LOG_DEBUG, "%s; %s: queue limit reached, " "segment dropped\n", s, __func__); free(s, M_TCPLOG); } m_freem(m); #ifdef TCP_REASS_LOGGING tcp_reass_log_dump(tp); #endif return (0); } } else { if (tp->t_segqlen >= min((so->so_rcv.sb_hiwat / tp->t_maxseg) + 1, tcp_reass_maxqueuelen)) { TCPSTAT_INC(tcps_rcvreassfull); *tlenp = 0; if ((s = tcp_log_addrs(&inp->inp_inc, th, NULL, NULL))) { log(LOG_DEBUG, "%s; %s: queue limit reached, " "segment dropped\n", s, __func__); free(s, M_TCPLOG); } m_freem(m); #ifdef TCP_REASS_LOGGING tcp_reass_log_dump(tp); #endif return (0); } } /* * Allocate a new queue entry. If we can't, or hit the zone limit * just drop the pkt. */ te = uma_zalloc(tcp_reass_zone, M_NOWAIT); if (te == NULL) { TCPSTAT_INC(tcps_rcvmemdrop); m_freem(m); *tlenp = 0; if ((s = tcp_log_addrs(&inp->inp_inc, th, NULL, NULL))) { log(LOG_DEBUG, "%s; %s: global zone limit " "reached, segment dropped\n", s, __func__); free(s, M_TCPLOG); } return (0); } tp->t_segqlen++; tp->t_rcvoopack++; TCPSTAT_INC(tcps_rcvoopack); TCPSTAT_ADD(tcps_rcvoobyte, *tlenp); /* Insert the new segment queue entry into place. */ te->tqe_m = m; te->tqe_flags = tcp_get_flags(th); te->tqe_len = *tlenp; te->tqe_start = th->th_seq; te->tqe_last = mlast; te->tqe_mbuf_cnt = lenofoh; tp->t_segqmbuflen += te->tqe_mbuf_cnt; if (p == NULL) { TAILQ_INSERT_HEAD(&tp->t_segq, te, tqe_q); } else { TAILQ_INSERT_AFTER(&tp->t_segq, p, te, tqe_q); } #ifdef TCP_REASS_LOGGING tcp_reass_log_new_in(tp, th->th_seq, *tlenp, m, TCP_R_LOG_NEW_ENTRY, te); #endif present: /* * Present data to user, advancing rcv_nxt through * completed sequence space. */ if (!TCPS_HAVEESTABLISHED(tp->t_state)) return (0); q = TAILQ_FIRST(&tp->t_segq); KASSERT(q == NULL || SEQ_GEQ(q->tqe_start, tp->rcv_nxt), ("Reassembly queue for %p has stale entry at head", tp)); if (!q || q->tqe_start != tp->rcv_nxt) { #ifdef TCP_REASS_LOGGING tcp_reass_log_dump(tp); #endif return (0); } - SOCKBUF_LOCK(&so->so_rcv); + SOCK_RECVBUF_LOCK(so); do { tp->rcv_nxt += q->tqe_len; flags = q->tqe_flags & TH_FIN; nq = TAILQ_NEXT(q, tqe_q); TAILQ_REMOVE(&tp->t_segq, q, tqe_q); if (so->so_rcv.sb_state & SBS_CANTRCVMORE) { m_freem(q->tqe_m); } else { #ifdef TCP_REASS_LOGGING tcp_reass_log_new_in(tp, q->tqe_start, q->tqe_len, q->tqe_m, TCP_R_LOG_READ, q); if (th != NULL) { tcp_log_reassm(tp, q, NULL, th->th_seq, *tlenp, TCP_R_LOG_READ, 1); } else { tcp_log_reassm(tp, q, NULL, 0, 0, TCP_R_LOG_READ, 1); } #endif sbappendstream_locked(&so->so_rcv, q->tqe_m, 0); } #ifdef TCP_REASS_LOGGING if (th != NULL) { tcp_log_reassm(tp, q, NULL, th->th_seq, *tlenp, TCP_R_LOG_READ, 2); } else { tcp_log_reassm(tp, q, NULL, 0, 0, TCP_R_LOG_READ, 2); } #endif KASSERT(tp->t_segqmbuflen >= q->tqe_mbuf_cnt, ("tp:%p seg queue goes negative", tp)); tp->t_segqmbuflen -= q->tqe_mbuf_cnt; uma_zfree(tcp_reass_zone, q); tp->t_segqlen--; q = nq; } while (q && q->tqe_start == tp->rcv_nxt); if (TAILQ_EMPTY(&tp->t_segq) && (tp->t_segqmbuflen != 0)) { #ifdef INVARIANTS panic("tp:%p segq:%p len:%d queue empty", tp, &tp->t_segq, tp->t_segqmbuflen); #else #ifdef TCP_REASS_LOGGING if (th != NULL) { tcp_log_reassm(tp, NULL, NULL, th->th_seq, *tlenp, TCP_R_LOG_ZERO, 0); } else { tcp_log_reassm(tp, NULL, NULL, 0, 0, TCP_R_LOG_ZERO, 0); } #endif tp->t_segqmbuflen = 0; #endif } #ifdef TCP_REASS_LOGGING tcp_reass_log_dump(tp); #endif tp->t_flags |= TF_WAKESOR; return (flags); } diff --git a/sys/netinet/tcp_subr.c b/sys/netinet/tcp_subr.c index 668d218b34a8..8bf011afe855 100644 --- a/sys/netinet/tcp_subr.c +++ b/sys/netinet/tcp_subr.c @@ -1,4798 +1,4798 @@ /*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include #include "opt_inet.h" #include "opt_inet6.h" #include "opt_ipsec.h" #include "opt_kern_tls.h" #include #include #include #include #include #ifdef TCP_HHOOK #include #endif #include #ifdef TCP_HHOOK #include #endif #ifdef KERN_TLS #include #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef INET6 #include #include #include #include #include #include #include #endif #include #ifdef INVARIANTS #define TCPSTATES #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef TCPPCAP #include #endif #ifdef TCP_OFFLOAD #include #endif #include #include #ifdef INET6 #include #endif #include #include #include #include #ifdef INET6 static ip6proto_ctlinput_t tcp6_ctlinput; static udp_tun_icmp_t tcp6_ctlinput_viaudp; #endif VNET_DEFINE(int, tcp_mssdflt) = TCP_MSS; #ifdef INET6 VNET_DEFINE(int, tcp_v6mssdflt) = TCP6_MSS; #endif VNET_DEFINE(uint32_t, tcp_ack_war_time_window) = 1000; SYSCTL_UINT(_net_inet_tcp, OID_AUTO, ack_war_timewindow, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_ack_war_time_window), 0, "Time interval in ms used to limit the number (ack_war_cnt) of challenge ACKs sent per TCP connection"); VNET_DEFINE(uint32_t, tcp_ack_war_cnt) = 5; SYSCTL_UINT(_net_inet_tcp, OID_AUTO, ack_war_cnt, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_ack_war_cnt), 0, "Maximum number of challenge ACKs sent per TCP connection during the time interval (ack_war_timewindow)"); struct rwlock tcp_function_lock; static int sysctl_net_inet_tcp_mss_check(SYSCTL_HANDLER_ARGS) { int error, new; new = V_tcp_mssdflt; error = sysctl_handle_int(oidp, &new, 0, req); if (error == 0 && req->newptr) { if (new < TCP_MINMSS) error = EINVAL; else V_tcp_mssdflt = new; } return (error); } SYSCTL_PROC(_net_inet_tcp, TCPCTL_MSSDFLT, mssdflt, CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, &VNET_NAME(tcp_mssdflt), 0, &sysctl_net_inet_tcp_mss_check, "I", "Default TCP Maximum Segment Size"); #ifdef INET6 static int sysctl_net_inet_tcp_mss_v6_check(SYSCTL_HANDLER_ARGS) { int error, new; new = V_tcp_v6mssdflt; error = sysctl_handle_int(oidp, &new, 0, req); if (error == 0 && req->newptr) { if (new < TCP_MINMSS) error = EINVAL; else V_tcp_v6mssdflt = new; } return (error); } SYSCTL_PROC(_net_inet_tcp, TCPCTL_V6MSSDFLT, v6mssdflt, CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, &VNET_NAME(tcp_v6mssdflt), 0, &sysctl_net_inet_tcp_mss_v6_check, "I", "Default TCP Maximum Segment Size for IPv6"); #endif /* INET6 */ /* * Minimum MSS we accept and use. This prevents DoS attacks where * we are forced to a ridiculous low MSS like 20 and send hundreds * of packets instead of one. The effect scales with the available * bandwidth and quickly saturates the CPU and network interface * with packet generation and sending. Set to zero to disable MINMSS * checking. This setting prevents us from sending too small packets. */ VNET_DEFINE(int, tcp_minmss) = TCP_MINMSS; SYSCTL_INT(_net_inet_tcp, OID_AUTO, minmss, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_minmss), 0, "Minimum TCP Maximum Segment Size"); VNET_DEFINE(int, tcp_do_rfc1323) = 1; SYSCTL_INT(_net_inet_tcp, TCPCTL_DO_RFC1323, rfc1323, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_do_rfc1323), 0, "Enable rfc1323 (high performance TCP) extensions"); /* * As of June 2021, several TCP stacks violate RFC 7323 from September 2014. * Some stacks negotiate TS, but never send them after connection setup. Some * stacks negotiate TS, but don't send them when sending keep-alive segments. * These include modern widely deployed TCP stacks. * Therefore tolerating violations for now... */ VNET_DEFINE(int, tcp_tolerate_missing_ts) = 1; SYSCTL_INT(_net_inet_tcp, OID_AUTO, tolerate_missing_ts, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_tolerate_missing_ts), 0, "Tolerate missing TCP timestamps"); VNET_DEFINE(int, tcp_ts_offset_per_conn) = 1; SYSCTL_INT(_net_inet_tcp, OID_AUTO, ts_offset_per_conn, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_ts_offset_per_conn), 0, "Initialize TCP timestamps per connection instead of per host pair"); /* How many connections are pacing */ static volatile uint32_t number_of_tcp_connections_pacing = 0; static uint32_t shadow_num_connections = 0; static counter_u64_t tcp_pacing_failures; static counter_u64_t tcp_dgp_failures; static uint32_t shadow_tcp_pacing_dgp = 0; static volatile uint32_t number_of_dgp_connections = 0; static int tcp_pacing_limit = 10000; SYSCTL_INT(_net_inet_tcp, OID_AUTO, pacing_limit, CTLFLAG_RW, &tcp_pacing_limit, 1000, "If the TCP stack does pacing, is there a limit (-1 = no, 0 = no pacing N = number of connections)"); static int tcp_dgp_limit = -1; SYSCTL_INT(_net_inet_tcp, OID_AUTO, dgp_limit, CTLFLAG_RW, &tcp_dgp_limit, -1, "If the TCP stack does DGP, is there a limit (-1 = no, 0 = no dgp N = number of connections)"); SYSCTL_UINT(_net_inet_tcp, OID_AUTO, pacing_count, CTLFLAG_RD, &shadow_num_connections, 0, "Number of TCP connections being paced"); SYSCTL_COUNTER_U64(_net_inet_tcp, OID_AUTO, pacing_failures, CTLFLAG_RD, &tcp_pacing_failures, "Number of times we failed to enable pacing to avoid exceeding the limit"); SYSCTL_COUNTER_U64(_net_inet_tcp, OID_AUTO, dgp_failures, CTLFLAG_RD, &tcp_dgp_failures, "Number of times we failed to enable dgp to avoid exceeding the limit"); static int tcp_log_debug = 0; SYSCTL_INT(_net_inet_tcp, OID_AUTO, log_debug, CTLFLAG_RW, &tcp_log_debug, 0, "Log errors caused by incoming TCP segments"); /* * Target size of TCP PCB hash tables. Must be a power of two. * * Note that this can be overridden by the kernel environment * variable net.inet.tcp.tcbhashsize */ #ifndef TCBHASHSIZE #define TCBHASHSIZE 0 #endif static int tcp_tcbhashsize = TCBHASHSIZE; SYSCTL_INT(_net_inet_tcp, OID_AUTO, tcbhashsize, CTLFLAG_RDTUN, &tcp_tcbhashsize, 0, "Size of TCP control-block hashtable"); static int do_tcpdrain = 1; SYSCTL_INT(_net_inet_tcp, OID_AUTO, do_tcpdrain, CTLFLAG_RW, &do_tcpdrain, 0, "Enable tcp_drain routine for extra help when low on mbufs"); SYSCTL_UINT(_net_inet_tcp, OID_AUTO, pcbcount, CTLFLAG_VNET | CTLFLAG_RD, &VNET_NAME(tcbinfo.ipi_count), 0, "Number of active PCBs"); VNET_DEFINE_STATIC(int, icmp_may_rst) = 1; #define V_icmp_may_rst VNET(icmp_may_rst) SYSCTL_INT(_net_inet_tcp, OID_AUTO, icmp_may_rst, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(icmp_may_rst), 0, "Certain ICMP unreachable messages may abort connections in SYN_SENT"); VNET_DEFINE_STATIC(int, tcp_isn_reseed_interval) = 0; #define V_tcp_isn_reseed_interval VNET(tcp_isn_reseed_interval) SYSCTL_INT(_net_inet_tcp, OID_AUTO, isn_reseed_interval, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_isn_reseed_interval), 0, "Seconds between reseeding of ISN secret"); static int tcp_soreceive_stream; SYSCTL_INT(_net_inet_tcp, OID_AUTO, soreceive_stream, CTLFLAG_RDTUN, &tcp_soreceive_stream, 0, "Using soreceive_stream for TCP sockets"); VNET_DEFINE(uma_zone_t, sack_hole_zone); #define V_sack_hole_zone VNET(sack_hole_zone) VNET_DEFINE(uint32_t, tcp_map_entries_limit) = 0; /* unlimited */ static int sysctl_net_inet_tcp_map_limit_check(SYSCTL_HANDLER_ARGS) { int error; uint32_t new; new = V_tcp_map_entries_limit; error = sysctl_handle_int(oidp, &new, 0, req); if (error == 0 && req->newptr) { /* only allow "0" and value > minimum */ if (new > 0 && new < TCP_MIN_MAP_ENTRIES_LIMIT) error = EINVAL; else V_tcp_map_entries_limit = new; } return (error); } SYSCTL_PROC(_net_inet_tcp, OID_AUTO, map_limit, CTLFLAG_VNET | CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, &VNET_NAME(tcp_map_entries_limit), 0, &sysctl_net_inet_tcp_map_limit_check, "IU", "Total sendmap entries limit"); VNET_DEFINE(uint32_t, tcp_map_split_limit) = 0; /* unlimited */ SYSCTL_UINT(_net_inet_tcp, OID_AUTO, split_limit, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(tcp_map_split_limit), 0, "Total sendmap split entries limit"); #ifdef TCP_HHOOK VNET_DEFINE(struct hhook_head *, tcp_hhh[HHOOK_TCP_LAST+1]); #endif #define TS_OFFSET_SECRET_LENGTH SIPHASH_KEY_LENGTH VNET_DEFINE_STATIC(u_char, ts_offset_secret[TS_OFFSET_SECRET_LENGTH]); #define V_ts_offset_secret VNET(ts_offset_secret) static int tcp_default_fb_init(struct tcpcb *tp, void **ptr); static void tcp_default_fb_fini(struct tcpcb *tp, int tcb_is_purged); static int tcp_default_handoff_ok(struct tcpcb *tp); static struct inpcb *tcp_notify(struct inpcb *, int); static struct inpcb *tcp_mtudisc_notify(struct inpcb *, int); static struct inpcb *tcp_mtudisc(struct inpcb *, int); static struct inpcb *tcp_drop_syn_sent(struct inpcb *, int); static char * tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th, const void *ip4hdr, const void *ip6hdr); static void tcp_default_switch_failed(struct tcpcb *tp); static ipproto_ctlinput_t tcp_ctlinput; static udp_tun_icmp_t tcp_ctlinput_viaudp; static struct tcp_function_block tcp_def_funcblk = { .tfb_tcp_block_name = "freebsd", .tfb_tcp_output = tcp_default_output, .tfb_tcp_do_segment = tcp_do_segment, .tfb_tcp_ctloutput = tcp_default_ctloutput, .tfb_tcp_handoff_ok = tcp_default_handoff_ok, .tfb_tcp_fb_init = tcp_default_fb_init, .tfb_tcp_fb_fini = tcp_default_fb_fini, .tfb_switch_failed = tcp_default_switch_failed, .tfb_flags = TCP_FUNC_DEFAULT_OK, }; static int tcp_fb_cnt = 0; struct tcp_funchead t_functions; VNET_DEFINE_STATIC(struct tcp_function_block *, tcp_func_set_ptr) = &tcp_def_funcblk; #define V_tcp_func_set_ptr VNET(tcp_func_set_ptr) void tcp_record_dsack(struct tcpcb *tp, tcp_seq start, tcp_seq end, int tlp) { TCPSTAT_INC(tcps_dsack_count); tp->t_dsack_pack++; if (tlp == 0) { if (SEQ_GT(end, start)) { tp->t_dsack_bytes += (end - start); TCPSTAT_ADD(tcps_dsack_bytes, (end - start)); } else { tp->t_dsack_tlp_bytes += (start - end); TCPSTAT_ADD(tcps_dsack_bytes, (start - end)); } } else { if (SEQ_GT(end, start)) { tp->t_dsack_bytes += (end - start); TCPSTAT_ADD(tcps_dsack_tlp_bytes, (end - start)); } else { tp->t_dsack_tlp_bytes += (start - end); TCPSTAT_ADD(tcps_dsack_tlp_bytes, (start - end)); } } } static struct tcp_function_block * find_tcp_functions_locked(struct tcp_function_set *fs) { struct tcp_function *f; struct tcp_function_block *blk = NULL; rw_assert(&tcp_function_lock, RA_LOCKED); TAILQ_FOREACH(f, &t_functions, tf_next) { if (strcmp(f->tf_name, fs->function_set_name) == 0) { blk = f->tf_fb; break; } } return (blk); } static struct tcp_function_block * find_tcp_fb_locked(struct tcp_function_block *blk, struct tcp_function **s) { struct tcp_function_block *rblk = NULL; struct tcp_function *f; rw_assert(&tcp_function_lock, RA_LOCKED); TAILQ_FOREACH(f, &t_functions, tf_next) { if (f->tf_fb == blk) { rblk = blk; if (s) { *s = f; } break; } } return (rblk); } struct tcp_function_block * find_and_ref_tcp_functions(struct tcp_function_set *fs) { struct tcp_function_block *blk; rw_rlock(&tcp_function_lock); blk = find_tcp_functions_locked(fs); if (blk) refcount_acquire(&blk->tfb_refcnt); rw_runlock(&tcp_function_lock); return (blk); } struct tcp_function_block * find_and_ref_tcp_fb(struct tcp_function_block *blk) { struct tcp_function_block *rblk; rw_rlock(&tcp_function_lock); rblk = find_tcp_fb_locked(blk, NULL); if (rblk) refcount_acquire(&rblk->tfb_refcnt); rw_runlock(&tcp_function_lock); return (rblk); } /* Find a matching alias for the given tcp_function_block. */ int find_tcp_function_alias(struct tcp_function_block *blk, struct tcp_function_set *fs) { struct tcp_function *f; int found; found = 0; rw_rlock(&tcp_function_lock); TAILQ_FOREACH(f, &t_functions, tf_next) { if ((f->tf_fb == blk) && (strncmp(f->tf_name, blk->tfb_tcp_block_name, TCP_FUNCTION_NAME_LEN_MAX) != 0)) { /* Matching function block with different name. */ strncpy(fs->function_set_name, f->tf_name, TCP_FUNCTION_NAME_LEN_MAX); found = 1; break; } } /* Null terminate the string appropriately. */ if (found) { fs->function_set_name[TCP_FUNCTION_NAME_LEN_MAX - 1] = '\0'; } else { fs->function_set_name[0] = '\0'; } rw_runlock(&tcp_function_lock); return (found); } static struct tcp_function_block * find_and_ref_tcp_default_fb(void) { struct tcp_function_block *rblk; rw_rlock(&tcp_function_lock); rblk = V_tcp_func_set_ptr; refcount_acquire(&rblk->tfb_refcnt); rw_runlock(&tcp_function_lock); return (rblk); } void tcp_switch_back_to_default(struct tcpcb *tp) { struct tcp_function_block *tfb; void *ptr = NULL; KASSERT(tp->t_fb != &tcp_def_funcblk, ("%s: called by the built-in default stack", __func__)); if (tp->t_fb->tfb_tcp_timer_stop_all != NULL) tp->t_fb->tfb_tcp_timer_stop_all(tp); /* * Now, we'll find a new function block to use. * Start by trying the current user-selected * default, unless this stack is the user-selected * default. */ tfb = find_and_ref_tcp_default_fb(); if (tfb == tp->t_fb) { refcount_release(&tfb->tfb_refcnt); tfb = NULL; } /* Does the stack accept this connection? */ if (tfb != NULL && (*tfb->tfb_tcp_handoff_ok)(tp)) { refcount_release(&tfb->tfb_refcnt); tfb = NULL; } /* Try to use that stack. */ if (tfb != NULL) { /* Initialize the new stack. If it succeeds, we are done. */ if (tfb->tfb_tcp_fb_init == NULL || (*tfb->tfb_tcp_fb_init)(tp, &ptr) == 0) { /* Release the old stack */ if (tp->t_fb->tfb_tcp_fb_fini != NULL) (*tp->t_fb->tfb_tcp_fb_fini)(tp, 0); refcount_release(&tp->t_fb->tfb_refcnt); /* Now set in all the pointers */ tp->t_fb = tfb; tp->t_fb_ptr = ptr; return; } /* * Initialization failed. Release the reference count on * the looked up default stack. */ refcount_release(&tfb->tfb_refcnt); } /* * If that wasn't feasible, use the built-in default * stack which is not allowed to reject anyone. */ tfb = find_and_ref_tcp_fb(&tcp_def_funcblk); if (tfb == NULL) { /* there always should be a default */ panic("Can't refer to tcp_def_funcblk"); } if ((*tfb->tfb_tcp_handoff_ok)(tp)) { /* The default stack cannot say no */ panic("Default stack rejects a new session?"); } if (tfb->tfb_tcp_fb_init != NULL && (*tfb->tfb_tcp_fb_init)(tp, &ptr)) { /* The default stack cannot fail */ panic("Default stack initialization failed"); } /* Now release the old stack */ if (tp->t_fb->tfb_tcp_fb_fini != NULL) (*tp->t_fb->tfb_tcp_fb_fini)(tp, 0); refcount_release(&tp->t_fb->tfb_refcnt); /* And set in the pointers to the new */ tp->t_fb = tfb; tp->t_fb_ptr = ptr; } static bool tcp_recv_udp_tunneled_packet(struct mbuf *m, int off, struct inpcb *inp, const struct sockaddr *sa, void *ctx) { struct ip *iph; #ifdef INET6 struct ip6_hdr *ip6; #endif struct udphdr *uh; struct tcphdr *th; int thlen; uint16_t port; TCPSTAT_INC(tcps_tunneled_pkts); if ((m->m_flags & M_PKTHDR) == 0) { /* Can't handle one that is not a pkt hdr */ TCPSTAT_INC(tcps_tunneled_errs); goto out; } thlen = sizeof(struct tcphdr); if (m->m_len < off + sizeof(struct udphdr) + thlen && (m = m_pullup(m, off + sizeof(struct udphdr) + thlen)) == NULL) { TCPSTAT_INC(tcps_tunneled_errs); goto out; } iph = mtod(m, struct ip *); uh = (struct udphdr *)((caddr_t)iph + off); th = (struct tcphdr *)(uh + 1); thlen = th->th_off << 2; if (m->m_len < off + sizeof(struct udphdr) + thlen) { m = m_pullup(m, off + sizeof(struct udphdr) + thlen); if (m == NULL) { TCPSTAT_INC(tcps_tunneled_errs); goto out; } else { iph = mtod(m, struct ip *); uh = (struct udphdr *)((caddr_t)iph + off); th = (struct tcphdr *)(uh + 1); } } m->m_pkthdr.tcp_tun_port = port = uh->uh_sport; bcopy(th, uh, m->m_len - off); m->m_len -= sizeof(struct udphdr); m->m_pkthdr.len -= sizeof(struct udphdr); /* * We use the same algorithm for * both UDP and TCP for c-sum. So * the code in tcp_input will skip * the checksum. So we do nothing * with the flag (m->m_pkthdr.csum_flags). */ switch (iph->ip_v) { #ifdef INET case IPVERSION: iph->ip_len = htons(ntohs(iph->ip_len) - sizeof(struct udphdr)); tcp_input_with_port(&m, &off, IPPROTO_TCP, port); break; #endif #ifdef INET6 case IPV6_VERSION >> 4: ip6 = mtod(m, struct ip6_hdr *); ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - sizeof(struct udphdr)); tcp6_input_with_port(&m, &off, IPPROTO_TCP, port); break; #endif default: goto out; break; } return (true); out: m_freem(m); return (true); } static int sysctl_net_inet_default_tcp_functions(SYSCTL_HANDLER_ARGS) { int error = ENOENT; struct tcp_function_set fs; struct tcp_function_block *blk; memset(&fs, 0, sizeof(fs)); rw_rlock(&tcp_function_lock); blk = find_tcp_fb_locked(V_tcp_func_set_ptr, NULL); if (blk) { /* Found him */ strcpy(fs.function_set_name, blk->tfb_tcp_block_name); fs.pcbcnt = blk->tfb_refcnt; } rw_runlock(&tcp_function_lock); error = sysctl_handle_string(oidp, fs.function_set_name, sizeof(fs.function_set_name), req); /* Check for error or no change */ if (error != 0 || req->newptr == NULL) return (error); rw_wlock(&tcp_function_lock); blk = find_tcp_functions_locked(&fs); if ((blk == NULL) || (blk->tfb_flags & TCP_FUNC_BEING_REMOVED)) { error = ENOENT; goto done; } if ((blk->tfb_flags & TCP_FUNC_DEFAULT_OK) == 0) { error = EINVAL; goto done; } V_tcp_func_set_ptr = blk; done: rw_wunlock(&tcp_function_lock); return (error); } SYSCTL_PROC(_net_inet_tcp, OID_AUTO, functions_default, CTLFLAG_VNET | CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_NEEDGIANT, NULL, 0, sysctl_net_inet_default_tcp_functions, "A", "Set/get the default TCP functions"); static int sysctl_net_inet_list_available(SYSCTL_HANDLER_ARGS) { int error, cnt, linesz; struct tcp_function *f; char *buffer, *cp; size_t bufsz, outsz; bool alias; cnt = 0; rw_rlock(&tcp_function_lock); TAILQ_FOREACH(f, &t_functions, tf_next) { cnt++; } rw_runlock(&tcp_function_lock); bufsz = (cnt+2) * ((TCP_FUNCTION_NAME_LEN_MAX * 2) + 13) + 1; buffer = malloc(bufsz, M_TEMP, M_WAITOK); error = 0; cp = buffer; linesz = snprintf(cp, bufsz, "\n%-32s%c %-32s %s\n", "Stack", 'D', "Alias", "PCB count"); cp += linesz; bufsz -= linesz; outsz = linesz; rw_rlock(&tcp_function_lock); TAILQ_FOREACH(f, &t_functions, tf_next) { alias = (f->tf_name != f->tf_fb->tfb_tcp_block_name); linesz = snprintf(cp, bufsz, "%-32s%c %-32s %u\n", f->tf_fb->tfb_tcp_block_name, (f->tf_fb == V_tcp_func_set_ptr) ? '*' : ' ', alias ? f->tf_name : "-", f->tf_fb->tfb_refcnt); if (linesz >= bufsz) { error = EOVERFLOW; break; } cp += linesz; bufsz -= linesz; outsz += linesz; } rw_runlock(&tcp_function_lock); if (error == 0) error = sysctl_handle_string(oidp, buffer, outsz + 1, req); free(buffer, M_TEMP); return (error); } SYSCTL_PROC(_net_inet_tcp, OID_AUTO, functions_available, CTLFLAG_VNET | CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT, NULL, 0, sysctl_net_inet_list_available, "A", "list available TCP Function sets"); VNET_DEFINE(int, tcp_udp_tunneling_port) = TCP_TUNNELING_PORT_DEFAULT; #ifdef INET VNET_DEFINE(struct socket *, udp4_tun_socket) = NULL; #define V_udp4_tun_socket VNET(udp4_tun_socket) #endif #ifdef INET6 VNET_DEFINE(struct socket *, udp6_tun_socket) = NULL; #define V_udp6_tun_socket VNET(udp6_tun_socket) #endif static struct sx tcpoudp_lock; static void tcp_over_udp_stop(void) { sx_assert(&tcpoudp_lock, SA_XLOCKED); #ifdef INET if (V_udp4_tun_socket != NULL) { soclose(V_udp4_tun_socket); V_udp4_tun_socket = NULL; } #endif #ifdef INET6 if (V_udp6_tun_socket != NULL) { soclose(V_udp6_tun_socket); V_udp6_tun_socket = NULL; } #endif } static int tcp_over_udp_start(void) { uint16_t port; int ret; #ifdef INET struct sockaddr_in sin; #endif #ifdef INET6 struct sockaddr_in6 sin6; #endif sx_assert(&tcpoudp_lock, SA_XLOCKED); port = V_tcp_udp_tunneling_port; if (ntohs(port) == 0) { /* Must have a port set */ return (EINVAL); } #ifdef INET if (V_udp4_tun_socket != NULL) { /* Already running -- must stop first */ return (EALREADY); } #endif #ifdef INET6 if (V_udp6_tun_socket != NULL) { /* Already running -- must stop first */ return (EALREADY); } #endif #ifdef INET if ((ret = socreate(PF_INET, &V_udp4_tun_socket, SOCK_DGRAM, IPPROTO_UDP, curthread->td_ucred, curthread))) { tcp_over_udp_stop(); return (ret); } /* Call the special UDP hook. */ if ((ret = udp_set_kernel_tunneling(V_udp4_tun_socket, tcp_recv_udp_tunneled_packet, tcp_ctlinput_viaudp, NULL))) { tcp_over_udp_stop(); return (ret); } /* Ok, we have a socket, bind it to the port. */ memset(&sin, 0, sizeof(struct sockaddr_in)); sin.sin_len = sizeof(struct sockaddr_in); sin.sin_family = AF_INET; sin.sin_port = htons(port); if ((ret = sobind(V_udp4_tun_socket, (struct sockaddr *)&sin, curthread))) { tcp_over_udp_stop(); return (ret); } #endif #ifdef INET6 if ((ret = socreate(PF_INET6, &V_udp6_tun_socket, SOCK_DGRAM, IPPROTO_UDP, curthread->td_ucred, curthread))) { tcp_over_udp_stop(); return (ret); } /* Call the special UDP hook. */ if ((ret = udp_set_kernel_tunneling(V_udp6_tun_socket, tcp_recv_udp_tunneled_packet, tcp6_ctlinput_viaudp, NULL))) { tcp_over_udp_stop(); return (ret); } /* Ok, we have a socket, bind it to the port. */ memset(&sin6, 0, sizeof(struct sockaddr_in6)); sin6.sin6_len = sizeof(struct sockaddr_in6); sin6.sin6_family = AF_INET6; sin6.sin6_port = htons(port); if ((ret = sobind(V_udp6_tun_socket, (struct sockaddr *)&sin6, curthread))) { tcp_over_udp_stop(); return (ret); } #endif return (0); } static int sysctl_net_inet_tcp_udp_tunneling_port_check(SYSCTL_HANDLER_ARGS) { int error; uint32_t old, new; old = V_tcp_udp_tunneling_port; new = old; error = sysctl_handle_int(oidp, &new, 0, req); if ((error == 0) && (req->newptr != NULL)) { if ((new < TCP_TUNNELING_PORT_MIN) || (new > TCP_TUNNELING_PORT_MAX)) { error = EINVAL; } else { sx_xlock(&tcpoudp_lock); V_tcp_udp_tunneling_port = new; if (old != 0) { tcp_over_udp_stop(); } if (new != 0) { error = tcp_over_udp_start(); if (error != 0) { V_tcp_udp_tunneling_port = 0; } } sx_xunlock(&tcpoudp_lock); } } return (error); } SYSCTL_PROC(_net_inet_tcp, OID_AUTO, udp_tunneling_port, CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, &VNET_NAME(tcp_udp_tunneling_port), 0, &sysctl_net_inet_tcp_udp_tunneling_port_check, "IU", "Tunneling port for tcp over udp"); VNET_DEFINE(int, tcp_udp_tunneling_overhead) = TCP_TUNNELING_OVERHEAD_DEFAULT; static int sysctl_net_inet_tcp_udp_tunneling_overhead_check(SYSCTL_HANDLER_ARGS) { int error, new; new = V_tcp_udp_tunneling_overhead; error = sysctl_handle_int(oidp, &new, 0, req); if (error == 0 && req->newptr) { if ((new < TCP_TUNNELING_OVERHEAD_MIN) || (new > TCP_TUNNELING_OVERHEAD_MAX)) error = EINVAL; else V_tcp_udp_tunneling_overhead = new; } return (error); } SYSCTL_PROC(_net_inet_tcp, OID_AUTO, udp_tunneling_overhead, CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, &VNET_NAME(tcp_udp_tunneling_overhead), 0, &sysctl_net_inet_tcp_udp_tunneling_overhead_check, "IU", "MSS reduction when using tcp over udp"); /* * Exports one (struct tcp_function_info) for each alias/name. */ static int sysctl_net_inet_list_func_info(SYSCTL_HANDLER_ARGS) { int cnt, error; struct tcp_function *f; struct tcp_function_info tfi; /* * We don't allow writes. */ if (req->newptr != NULL) return (EINVAL); /* * Wire the old buffer so we can directly copy the functions to * user space without dropping the lock. */ if (req->oldptr != NULL) { error = sysctl_wire_old_buffer(req, 0); if (error) return (error); } /* * Walk the list and copy out matching entries. If INVARIANTS * is compiled in, also walk the list to verify the length of * the list matches what we have recorded. */ rw_rlock(&tcp_function_lock); cnt = 0; #ifndef INVARIANTS if (req->oldptr == NULL) { cnt = tcp_fb_cnt; goto skip_loop; } #endif TAILQ_FOREACH(f, &t_functions, tf_next) { #ifdef INVARIANTS cnt++; #endif if (req->oldptr != NULL) { bzero(&tfi, sizeof(tfi)); tfi.tfi_refcnt = f->tf_fb->tfb_refcnt; tfi.tfi_id = f->tf_fb->tfb_id; (void)strlcpy(tfi.tfi_alias, f->tf_name, sizeof(tfi.tfi_alias)); (void)strlcpy(tfi.tfi_name, f->tf_fb->tfb_tcp_block_name, sizeof(tfi.tfi_name)); error = SYSCTL_OUT(req, &tfi, sizeof(tfi)); /* * Don't stop on error, as that is the * mechanism we use to accumulate length * information if the buffer was too short. */ } } KASSERT(cnt == tcp_fb_cnt, ("%s: cnt (%d) != tcp_fb_cnt (%d)", __func__, cnt, tcp_fb_cnt)); #ifndef INVARIANTS skip_loop: #endif rw_runlock(&tcp_function_lock); if (req->oldptr == NULL) error = SYSCTL_OUT(req, NULL, (cnt + 1) * sizeof(struct tcp_function_info)); return (error); } SYSCTL_PROC(_net_inet_tcp, OID_AUTO, function_info, CTLTYPE_OPAQUE | CTLFLAG_SKIP | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0, sysctl_net_inet_list_func_info, "S,tcp_function_info", "List TCP function block name-to-ID mappings"); /* * tfb_tcp_handoff_ok() function for the default stack. * Note that we'll basically try to take all comers. */ static int tcp_default_handoff_ok(struct tcpcb *tp) { return (0); } /* * tfb_tcp_fb_init() function for the default stack. * * This handles making sure we have appropriate timers set if you are * transitioning a socket that has some amount of setup done. * * The init() fuction from the default can *never* return non-zero i.e. * it is required to always succeed since it is the stack of last resort! */ static int tcp_default_fb_init(struct tcpcb *tp, void **ptr) { struct socket *so = tptosocket(tp); int rexmt; INP_WLOCK_ASSERT(tptoinpcb(tp)); /* We don't use the pointer */ *ptr = NULL; KASSERT(tp->t_state < TCPS_TIME_WAIT, ("%s: connection %p in unexpected state %d", __func__, tp, tp->t_state)); /* Make sure we get no interesting mbuf queuing behavior */ /* All mbuf queue/ack compress flags should be off */ tcp_lro_features_off(tp); /* Cancel the GP measurement in progress */ tp->t_flags &= ~TF_GPUTINPROG; /* Validate the timers are not in usec, if they are convert */ tcp_change_time_units(tp, TCP_TMR_GRANULARITY_TICKS); if ((tp->t_state == TCPS_SYN_SENT) || (tp->t_state == TCPS_SYN_RECEIVED)) rexmt = tcp_rexmit_initial * tcp_backoff[tp->t_rxtshift]; else rexmt = TCP_REXMTVAL(tp) * tcp_backoff[tp->t_rxtshift]; if (tp->t_rxtshift == 0) tp->t_rxtcur = rexmt; else TCPT_RANGESET(tp->t_rxtcur, rexmt, tp->t_rttmin, TCPTV_REXMTMAX); /* * Nothing to do for ESTABLISHED or LISTEN states. And, we don't * know what to do for unexpected states (which includes TIME_WAIT). */ if (tp->t_state <= TCPS_LISTEN || tp->t_state >= TCPS_TIME_WAIT) return (0); /* * Make sure some kind of transmission timer is set if there is * outstanding data. */ if ((!TCPS_HAVEESTABLISHED(tp->t_state) || sbavail(&so->so_snd) || tp->snd_una != tp->snd_max) && !(tcp_timer_active(tp, TT_REXMT) || tcp_timer_active(tp, TT_PERSIST))) { /* * If the session has established and it looks like it should * be in the persist state, set the persist timer. Otherwise, * set the retransmit timer. */ if (TCPS_HAVEESTABLISHED(tp->t_state) && tp->snd_wnd == 0 && (int32_t)(tp->snd_nxt - tp->snd_una) < (int32_t)sbavail(&so->so_snd)) tcp_setpersist(tp); else tcp_timer_activate(tp, TT_REXMT, TP_RXTCUR(tp)); } /* All non-embryonic sessions get a keepalive timer. */ if (!tcp_timer_active(tp, TT_KEEP)) tcp_timer_activate(tp, TT_KEEP, TCPS_HAVEESTABLISHED(tp->t_state) ? TP_KEEPIDLE(tp) : TP_KEEPINIT(tp)); /* * Make sure critical variables are initialized * if transitioning while in Recovery. */ if IN_FASTRECOVERY(tp->t_flags) { if (tp->sackhint.recover_fs == 0) tp->sackhint.recover_fs = max(1, tp->snd_nxt - tp->snd_una); } return (0); } /* * tfb_tcp_fb_fini() function for the default stack. * * This changes state as necessary (or prudent) to prepare for another stack * to assume responsibility for the connection. */ static void tcp_default_fb_fini(struct tcpcb *tp, int tcb_is_purged) { INP_WLOCK_ASSERT(tptoinpcb(tp)); #ifdef TCP_BLACKBOX tcp_log_flowend(tp); #endif tp->t_acktime = 0; return; } MALLOC_DEFINE(M_TCPLOG, "tcplog", "TCP address and flags print buffers"); MALLOC_DEFINE(M_TCPFUNCTIONS, "tcpfunc", "TCP function set memory"); static struct mtx isn_mtx; #define ISN_LOCK_INIT() mtx_init(&isn_mtx, "isn_mtx", NULL, MTX_DEF) #define ISN_LOCK() mtx_lock(&isn_mtx) #define ISN_UNLOCK() mtx_unlock(&isn_mtx) INPCBSTORAGE_DEFINE(tcpcbstor, tcpcb, "tcpinp", "tcp_inpcb", "tcp", "tcphash"); /* * Take a value and get the next power of 2 that doesn't overflow. * Used to size the tcp_inpcb hash buckets. */ static int maketcp_hashsize(int size) { int hashsize; /* * auto tune. * get the next power of 2 higher than maxsockets. */ hashsize = 1 << fls(size); /* catch overflow, and just go one power of 2 smaller */ if (hashsize < size) { hashsize = 1 << (fls(size) - 1); } return (hashsize); } static volatile int next_tcp_stack_id = 1; /* * Register a TCP function block with the name provided in the names * array. (Note that this function does NOT automatically register * blk->tfb_tcp_block_name as a stack name. Therefore, you should * explicitly include blk->tfb_tcp_block_name in the list of names if * you wish to register the stack with that name.) * * Either all name registrations will succeed or all will fail. If * a name registration fails, the function will update the num_names * argument to point to the array index of the name that encountered * the failure. * * Returns 0 on success, or an error code on failure. */ int register_tcp_functions_as_names(struct tcp_function_block *blk, int wait, const char *names[], int *num_names) { struct tcp_function *f[TCP_FUNCTION_NAME_NUM_MAX]; struct tcp_function_set fs; int error, i, num_registered; KASSERT(names != NULL, ("%s: Called with NULL name list", __func__)); KASSERT(*num_names > 0, ("%s: Called with non-positive length of name list", __func__)); KASSERT(rw_initialized(&tcp_function_lock), ("%s: called too early", __func__)); if (*num_names > TCP_FUNCTION_NAME_NUM_MAX) { /* Too many names. */ *num_names = 0; return (E2BIG); } if ((blk->tfb_tcp_output == NULL) || (blk->tfb_tcp_do_segment == NULL) || (blk->tfb_tcp_ctloutput == NULL) || (blk->tfb_tcp_handoff_ok == NULL) || (strlen(blk->tfb_tcp_block_name) == 0)) { /* These functions are required and a name is needed. */ *num_names = 0; return (EINVAL); } for (i = 0; i < *num_names; i++) { f[i] = malloc(sizeof(struct tcp_function), M_TCPFUNCTIONS, wait); if (f[i] == NULL) { while (--i >= 0) free(f[i], M_TCPFUNCTIONS); *num_names = 0; return (ENOMEM); } } num_registered = 0; rw_wlock(&tcp_function_lock); if (find_tcp_fb_locked(blk, NULL) != NULL) { /* A TCP function block can only be registered once. */ error = EALREADY; goto cleanup; } if (blk->tfb_flags & TCP_FUNC_BEING_REMOVED) { error = EINVAL; goto cleanup; } refcount_init(&blk->tfb_refcnt, 0); blk->tfb_id = atomic_fetchadd_int(&next_tcp_stack_id, 1); for (i = 0; i < *num_names; i++) { (void)strlcpy(fs.function_set_name, names[i], sizeof(fs.function_set_name)); if (find_tcp_functions_locked(&fs) != NULL) { /* Duplicate name space not allowed */ error = EALREADY; goto cleanup; } f[i]->tf_fb = blk; (void)strlcpy(f[i]->tf_name, names[i], sizeof(f[i]->tf_name)); TAILQ_INSERT_TAIL(&t_functions, f[i], tf_next); tcp_fb_cnt++; num_registered++; } rw_wunlock(&tcp_function_lock); return (0); cleanup: /* Remove the entries just added. */ for (i = 0; i < *num_names; i++) { if (i < num_registered) { TAILQ_REMOVE(&t_functions, f[i], tf_next); tcp_fb_cnt--; } f[i]->tf_fb = NULL; free(f[i], M_TCPFUNCTIONS); } rw_wunlock(&tcp_function_lock); *num_names = num_registered; return (error); } /* * Register a TCP function block using the name provided in the name * argument. * * Returns 0 on success, or an error code on failure. */ int register_tcp_functions_as_name(struct tcp_function_block *blk, const char *name, int wait) { const char *name_list[1]; int num_names, rv; num_names = 1; if (name != NULL) name_list[0] = name; else name_list[0] = blk->tfb_tcp_block_name; rv = register_tcp_functions_as_names(blk, wait, name_list, &num_names); return (rv); } /* * Register a TCP function block using the name defined in * blk->tfb_tcp_block_name. * * Returns 0 on success, or an error code on failure. */ int register_tcp_functions(struct tcp_function_block *blk, int wait) { return (register_tcp_functions_as_name(blk, NULL, wait)); } /* * Deregister all names associated with a function block. This * functionally removes the function block from use within the system. * * When called with a true quiesce argument, mark the function block * as being removed so no more stacks will use it and determine * whether the removal would succeed. * * When called with a false quiesce argument, actually attempt the * removal. * * When called with a force argument, attempt to switch all TCBs to * use the default stack instead of returning EBUSY. * * Returns 0 on success (or if the removal would succeed), or an error * code on failure. */ int deregister_tcp_functions(struct tcp_function_block *blk, bool quiesce, bool force) { struct tcp_function *f; VNET_ITERATOR_DECL(vnet_iter); if (blk == &tcp_def_funcblk) { /* You can't un-register the default */ return (EPERM); } rw_wlock(&tcp_function_lock); VNET_LIST_RLOCK_NOSLEEP(); VNET_FOREACH(vnet_iter) { CURVNET_SET(vnet_iter); if (blk == V_tcp_func_set_ptr) { /* You can't free the current default in some vnet. */ CURVNET_RESTORE(); VNET_LIST_RUNLOCK_NOSLEEP(); rw_wunlock(&tcp_function_lock); return (EBUSY); } CURVNET_RESTORE(); } VNET_LIST_RUNLOCK_NOSLEEP(); /* Mark the block so no more stacks can use it. */ blk->tfb_flags |= TCP_FUNC_BEING_REMOVED; /* * If TCBs are still attached to the stack, attempt to switch them * to the default stack. */ if (force && blk->tfb_refcnt) { struct inpcb *inp; struct tcpcb *tp; VNET_ITERATOR_DECL(vnet_iter); rw_wunlock(&tcp_function_lock); VNET_LIST_RLOCK(); VNET_FOREACH(vnet_iter) { CURVNET_SET(vnet_iter); struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, INPLOOKUP_WLOCKPCB); while ((inp = inp_next(&inpi)) != NULL) { tp = intotcpcb(inp); if (tp == NULL || tp->t_fb != blk) continue; tcp_switch_back_to_default(tp); } CURVNET_RESTORE(); } VNET_LIST_RUNLOCK(); rw_wlock(&tcp_function_lock); } if (blk->tfb_refcnt) { /* TCBs still attached. */ rw_wunlock(&tcp_function_lock); return (EBUSY); } if (quiesce) { /* Skip removal. */ rw_wunlock(&tcp_function_lock); return (0); } /* Remove any function names that map to this function block. */ while (find_tcp_fb_locked(blk, &f) != NULL) { TAILQ_REMOVE(&t_functions, f, tf_next); tcp_fb_cnt--; f->tf_fb = NULL; free(f, M_TCPFUNCTIONS); } rw_wunlock(&tcp_function_lock); return (0); } static void tcp_drain(void) { struct epoch_tracker et; VNET_ITERATOR_DECL(vnet_iter); if (!do_tcpdrain) return; NET_EPOCH_ENTER(et); VNET_LIST_RLOCK_NOSLEEP(); VNET_FOREACH(vnet_iter) { CURVNET_SET(vnet_iter); struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, INPLOOKUP_WLOCKPCB); struct inpcb *inpb; struct tcpcb *tcpb; /* * Walk the tcpbs, if existing, and flush the reassembly queue, * if there is one... * XXX: The "Net/3" implementation doesn't imply that the TCP * reassembly queue should be flushed, but in a situation * where we're really low on mbufs, this is potentially * useful. */ while ((inpb = inp_next(&inpi)) != NULL) { if ((tcpb = intotcpcb(inpb)) != NULL) { tcp_reass_flush(tcpb); tcp_clean_sackreport(tcpb); #ifdef TCP_BLACKBOX tcp_log_drain(tcpb); #endif #ifdef TCPPCAP if (tcp_pcap_aggressive_free) { /* Free the TCP PCAP queues. */ tcp_pcap_drain(&(tcpb->t_inpkts)); tcp_pcap_drain(&(tcpb->t_outpkts)); } #endif } } CURVNET_RESTORE(); } VNET_LIST_RUNLOCK_NOSLEEP(); NET_EPOCH_EXIT(et); } static void tcp_vnet_init(void *arg __unused) { #ifdef TCP_HHOOK if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN, &V_tcp_hhh[HHOOK_TCP_EST_IN], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0) printf("%s: WARNING: unable to register helper hook\n", __func__); if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT, &V_tcp_hhh[HHOOK_TCP_EST_OUT], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0) printf("%s: WARNING: unable to register helper hook\n", __func__); #endif #ifdef STATS if (tcp_stats_init()) printf("%s: WARNING: unable to initialise TCP stats\n", __func__); #endif in_pcbinfo_init(&V_tcbinfo, &tcpcbstor, tcp_tcbhashsize, tcp_tcbhashsize); syncache_init(); tcp_hc_init(); TUNABLE_INT_FETCH("net.inet.tcp.sack.enable", &V_tcp_do_sack); V_sack_hole_zone = uma_zcreate("sackhole", sizeof(struct sackhole), NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); tcp_fastopen_init(); COUNTER_ARRAY_ALLOC(V_tcps_states, TCP_NSTATES, M_WAITOK); VNET_PCPUSTAT_ALLOC(tcpstat, M_WAITOK); V_tcp_msl = TCPTV_MSL; arc4rand(&V_ts_offset_secret, sizeof(V_ts_offset_secret), 0); } VNET_SYSINIT(tcp_vnet_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, tcp_vnet_init, NULL); static void tcp_init(void *arg __unused) { int hashsize; tcp_reass_global_init(); /* XXX virtualize those below? */ tcp_delacktime = TCPTV_DELACK; tcp_keepinit = TCPTV_KEEP_INIT; tcp_keepidle = TCPTV_KEEP_IDLE; tcp_keepintvl = TCPTV_KEEPINTVL; tcp_maxpersistidle = TCPTV_KEEP_IDLE; tcp_rexmit_initial = TCPTV_RTOBASE; if (tcp_rexmit_initial < 1) tcp_rexmit_initial = 1; tcp_rexmit_min = TCPTV_MIN; if (tcp_rexmit_min < 1) tcp_rexmit_min = 1; tcp_persmin = TCPTV_PERSMIN; tcp_persmax = TCPTV_PERSMAX; tcp_rexmit_slop = TCPTV_CPU_VAR; tcp_finwait2_timeout = TCPTV_FINWAIT2_TIMEOUT; /* Setup the tcp function block list */ TAILQ_INIT(&t_functions); rw_init(&tcp_function_lock, "tcp_func_lock"); register_tcp_functions(&tcp_def_funcblk, M_WAITOK); sx_init(&tcpoudp_lock, "TCP over UDP configuration"); #ifdef TCP_BLACKBOX /* Initialize the TCP logging data. */ tcp_log_init(); #endif if (tcp_soreceive_stream) { #ifdef INET tcp_protosw.pr_soreceive = soreceive_stream; #endif #ifdef INET6 tcp6_protosw.pr_soreceive = soreceive_stream; #endif /* INET6 */ } #ifdef INET6 max_protohdr_grow(sizeof(struct ip6_hdr) + sizeof(struct tcphdr)); #else /* INET6 */ max_protohdr_grow(sizeof(struct tcpiphdr)); #endif /* INET6 */ ISN_LOCK_INIT(); EVENTHANDLER_REGISTER(shutdown_pre_sync, tcp_fini, NULL, SHUTDOWN_PRI_DEFAULT); EVENTHANDLER_REGISTER(vm_lowmem, tcp_drain, NULL, LOWMEM_PRI_DEFAULT); EVENTHANDLER_REGISTER(mbuf_lowmem, tcp_drain, NULL, LOWMEM_PRI_DEFAULT); tcp_inp_lro_direct_queue = counter_u64_alloc(M_WAITOK); tcp_inp_lro_wokeup_queue = counter_u64_alloc(M_WAITOK); tcp_inp_lro_compressed = counter_u64_alloc(M_WAITOK); tcp_inp_lro_locks_taken = counter_u64_alloc(M_WAITOK); tcp_extra_mbuf = counter_u64_alloc(M_WAITOK); tcp_would_have_but = counter_u64_alloc(M_WAITOK); tcp_comp_total = counter_u64_alloc(M_WAITOK); tcp_uncomp_total = counter_u64_alloc(M_WAITOK); tcp_bad_csums = counter_u64_alloc(M_WAITOK); tcp_pacing_failures = counter_u64_alloc(M_WAITOK); tcp_dgp_failures = counter_u64_alloc(M_WAITOK); #ifdef TCPPCAP tcp_pcap_init(); #endif hashsize = tcp_tcbhashsize; if (hashsize == 0) { /* * Auto tune the hash size based on maxsockets. * A perfect hash would have a 1:1 mapping * (hashsize = maxsockets) however it's been * suggested that O(2) average is better. */ hashsize = maketcp_hashsize(maxsockets / 4); /* * Our historical default is 512, * do not autotune lower than this. */ if (hashsize < 512) hashsize = 512; if (bootverbose) printf("%s: %s auto tuned to %d\n", __func__, "net.inet.tcp.tcbhashsize", hashsize); } /* * We require a hashsize to be a power of two. * Previously if it was not a power of two we would just reset it * back to 512, which could be a nasty surprise if you did not notice * the error message. * Instead what we do is clip it to the closest power of two lower * than the specified hash value. */ if (!powerof2(hashsize)) { int oldhashsize = hashsize; hashsize = maketcp_hashsize(hashsize); /* prevent absurdly low value */ if (hashsize < 16) hashsize = 16; printf("%s: WARNING: TCB hash size not a power of 2, " "clipped from %d to %d.\n", __func__, oldhashsize, hashsize); } tcp_tcbhashsize = hashsize; #ifdef INET IPPROTO_REGISTER(IPPROTO_TCP, tcp_input, tcp_ctlinput); #endif #ifdef INET6 IP6PROTO_REGISTER(IPPROTO_TCP, tcp6_input, tcp6_ctlinput); #endif } SYSINIT(tcp_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, tcp_init, NULL); #ifdef VIMAGE static void tcp_destroy(void *unused __unused) { int n; #ifdef TCP_HHOOK int error; #endif /* * All our processes are gone, all our sockets should be cleaned * up, which means, we should be past the tcp_discardcb() calls. * Sleep to let all tcpcb timers really disappear and cleanup. */ for (;;) { INP_INFO_WLOCK(&V_tcbinfo); n = V_tcbinfo.ipi_count; INP_INFO_WUNLOCK(&V_tcbinfo); if (n == 0) break; pause("tcpdes", hz / 10); } tcp_hc_destroy(); syncache_destroy(); in_pcbinfo_destroy(&V_tcbinfo); /* tcp_discardcb() clears the sack_holes up. */ uma_zdestroy(V_sack_hole_zone); /* * Cannot free the zone until all tcpcbs are released as we attach * the allocations to them. */ tcp_fastopen_destroy(); COUNTER_ARRAY_FREE(V_tcps_states, TCP_NSTATES); VNET_PCPUSTAT_FREE(tcpstat); #ifdef TCP_HHOOK error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_IN]); if (error != 0) { printf("%s: WARNING: unable to deregister helper hook " "type=%d, id=%d: error %d returned\n", __func__, HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN, error); } error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_OUT]); if (error != 0) { printf("%s: WARNING: unable to deregister helper hook " "type=%d, id=%d: error %d returned\n", __func__, HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT, error); } #endif } VNET_SYSUNINIT(tcp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, tcp_destroy, NULL); #endif void tcp_fini(void *xtp) { } /* * Fill in the IP and TCP headers for an outgoing packet, given the tcpcb. * tcp_template used to store this data in mbufs, but we now recopy it out * of the tcpcb each time to conserve mbufs. */ void tcpip_fillheaders(struct inpcb *inp, uint16_t port, void *ip_ptr, void *tcp_ptr) { struct tcphdr *th = (struct tcphdr *)tcp_ptr; INP_WLOCK_ASSERT(inp); #ifdef INET6 if ((inp->inp_vflag & INP_IPV6) != 0) { struct ip6_hdr *ip6; ip6 = (struct ip6_hdr *)ip_ptr; ip6->ip6_flow = (ip6->ip6_flow & ~IPV6_FLOWINFO_MASK) | (inp->inp_flow & IPV6_FLOWINFO_MASK); ip6->ip6_vfc = (ip6->ip6_vfc & ~IPV6_VERSION_MASK) | (IPV6_VERSION & IPV6_VERSION_MASK); if (port == 0) ip6->ip6_nxt = IPPROTO_TCP; else ip6->ip6_nxt = IPPROTO_UDP; ip6->ip6_plen = htons(sizeof(struct tcphdr)); ip6->ip6_src = inp->in6p_laddr; ip6->ip6_dst = inp->in6p_faddr; } #endif /* INET6 */ #if defined(INET6) && defined(INET) else #endif #ifdef INET { struct ip *ip; ip = (struct ip *)ip_ptr; ip->ip_v = IPVERSION; ip->ip_hl = 5; ip->ip_tos = inp->inp_ip_tos; ip->ip_len = 0; ip->ip_id = 0; ip->ip_off = 0; ip->ip_ttl = inp->inp_ip_ttl; ip->ip_sum = 0; if (port == 0) ip->ip_p = IPPROTO_TCP; else ip->ip_p = IPPROTO_UDP; ip->ip_src = inp->inp_laddr; ip->ip_dst = inp->inp_faddr; } #endif /* INET */ th->th_sport = inp->inp_lport; th->th_dport = inp->inp_fport; th->th_seq = 0; th->th_ack = 0; th->th_off = 5; tcp_set_flags(th, 0); th->th_win = 0; th->th_urp = 0; th->th_sum = 0; /* in_pseudo() is called later for ipv4 */ } /* * Create template to be used to send tcp packets on a connection. * Allocates an mbuf and fills in a skeletal tcp/ip header. The only * use for this function is in keepalives, which use tcp_respond. */ struct tcptemp * tcpip_maketemplate(struct inpcb *inp) { struct tcptemp *t; t = malloc(sizeof(*t), M_TEMP, M_NOWAIT); if (t == NULL) return (NULL); tcpip_fillheaders(inp, 0, (void *)&t->tt_ipgen, (void *)&t->tt_t); return (t); } /* * Send a single message to the TCP at address specified by * the given TCP/IP header. If m == NULL, then we make a copy * of the tcpiphdr at th and send directly to the addressed host. * This is used to force keep alive messages out using the TCP * template for a connection. If flags are given then we send * a message back to the TCP which originated the segment th, * and discard the mbuf containing it and any other attached mbufs. * * In any case the ack and sequence number of the transmitted * segment are as specified by the parameters. * * NOTE: If m != NULL, then th must point to *inside* the mbuf. */ void tcp_respond(struct tcpcb *tp, void *ipgen, struct tcphdr *th, struct mbuf *m, tcp_seq ack, tcp_seq seq, uint16_t flags) { struct tcpopt to; struct inpcb *inp; struct ip *ip; struct mbuf *optm; struct udphdr *uh = NULL; struct tcphdr *nth; struct tcp_log_buffer *lgb; u_char *optp; #ifdef INET6 struct ip6_hdr *ip6; int isipv6; #endif /* INET6 */ int optlen, tlen, win, ulen; int ect = 0; bool incl_opts; uint16_t port; int output_ret; #ifdef INVARIANTS int thflags = tcp_get_flags(th); #endif KASSERT(tp != NULL || m != NULL, ("tcp_respond: tp and m both NULL")); NET_EPOCH_ASSERT(); #ifdef INET6 isipv6 = ((struct ip *)ipgen)->ip_v == (IPV6_VERSION >> 4); ip6 = ipgen; #endif /* INET6 */ ip = ipgen; if (tp != NULL) { inp = tptoinpcb(tp); INP_LOCK_ASSERT(inp); } else inp = NULL; if (m != NULL) { #ifdef INET6 if (isipv6 && ip6 && (ip6->ip6_nxt == IPPROTO_UDP)) port = m->m_pkthdr.tcp_tun_port; else #endif if (ip && (ip->ip_p == IPPROTO_UDP)) port = m->m_pkthdr.tcp_tun_port; else port = 0; } else port = tp->t_port; incl_opts = false; win = 0; if (tp != NULL) { if (!(flags & TH_RST)) { win = sbspace(&inp->inp_socket->so_rcv); if (win > TCP_MAXWIN << tp->rcv_scale) win = TCP_MAXWIN << tp->rcv_scale; } if ((tp->t_flags & TF_NOOPT) == 0) incl_opts = true; } if (m == NULL) { m = m_gethdr(M_NOWAIT, MT_DATA); if (m == NULL) return; m->m_data += max_linkhdr; #ifdef INET6 if (isipv6) { bcopy((caddr_t)ip6, mtod(m, caddr_t), sizeof(struct ip6_hdr)); ip6 = mtod(m, struct ip6_hdr *); nth = (struct tcphdr *)(ip6 + 1); if (port) { /* Insert a UDP header */ uh = (struct udphdr *)nth; uh->uh_sport = htons(V_tcp_udp_tunneling_port); uh->uh_dport = port; nth = (struct tcphdr *)(uh + 1); } } else #endif /* INET6 */ { bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip)); ip = mtod(m, struct ip *); nth = (struct tcphdr *)(ip + 1); if (port) { /* Insert a UDP header */ uh = (struct udphdr *)nth; uh->uh_sport = htons(V_tcp_udp_tunneling_port); uh->uh_dport = port; nth = (struct tcphdr *)(uh + 1); } } bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr)); flags = TH_ACK; } else if ((!M_WRITABLE(m)) || (port != 0)) { struct mbuf *n; /* Can't reuse 'm', allocate a new mbuf. */ n = m_gethdr(M_NOWAIT, MT_DATA); if (n == NULL) { m_freem(m); return; } if (!m_dup_pkthdr(n, m, M_NOWAIT)) { m_freem(m); m_freem(n); return; } n->m_data += max_linkhdr; /* m_len is set later */ #define xchg(a,b,type) { type t; t=a; a=b; b=t; } #ifdef INET6 if (isipv6) { bcopy((caddr_t)ip6, mtod(n, caddr_t), sizeof(struct ip6_hdr)); ip6 = mtod(n, struct ip6_hdr *); xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); nth = (struct tcphdr *)(ip6 + 1); if (port) { /* Insert a UDP header */ uh = (struct udphdr *)nth; uh->uh_sport = htons(V_tcp_udp_tunneling_port); uh->uh_dport = port; nth = (struct tcphdr *)(uh + 1); } } else #endif /* INET6 */ { bcopy((caddr_t)ip, mtod(n, caddr_t), sizeof(struct ip)); ip = mtod(n, struct ip *); xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t); nth = (struct tcphdr *)(ip + 1); if (port) { /* Insert a UDP header */ uh = (struct udphdr *)nth; uh->uh_sport = htons(V_tcp_udp_tunneling_port); uh->uh_dport = port; nth = (struct tcphdr *)(uh + 1); } } bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr)); xchg(nth->th_dport, nth->th_sport, uint16_t); th = nth; m_freem(m); m = n; } else { /* * reuse the mbuf. * XXX MRT We inherit the FIB, which is lucky. */ m_freem(m->m_next); m->m_next = NULL; m->m_data = (caddr_t)ipgen; /* clear any receive flags for proper bpf timestamping */ m->m_flags &= ~(M_TSTMP | M_TSTMP_LRO); /* m_len is set later */ #ifdef INET6 if (isipv6) { xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); nth = (struct tcphdr *)(ip6 + 1); } else #endif /* INET6 */ { xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t); nth = (struct tcphdr *)(ip + 1); } if (th != nth) { /* * this is usually a case when an extension header * exists between the IPv6 header and the * TCP header. */ nth->th_sport = th->th_sport; nth->th_dport = th->th_dport; } xchg(nth->th_dport, nth->th_sport, uint16_t); #undef xchg } tlen = 0; #ifdef INET6 if (isipv6) tlen = sizeof (struct ip6_hdr) + sizeof (struct tcphdr); #endif #if defined(INET) && defined(INET6) else #endif #ifdef INET tlen = sizeof (struct tcpiphdr); #endif if (port) tlen += sizeof (struct udphdr); #ifdef INVARIANTS m->m_len = 0; KASSERT(M_TRAILINGSPACE(m) >= tlen, ("Not enough trailing space for message (m=%p, need=%d, have=%ld)", m, tlen, (long)M_TRAILINGSPACE(m))); #endif m->m_len = tlen; to.to_flags = 0; if (incl_opts) { ect = tcp_ecn_output_established(tp, &flags, 0, false); /* Make sure we have room. */ if (M_TRAILINGSPACE(m) < TCP_MAXOLEN) { m->m_next = m_get(M_NOWAIT, MT_DATA); if (m->m_next) { optp = mtod(m->m_next, u_char *); optm = m->m_next; } else incl_opts = false; } else { optp = (u_char *) (nth + 1); optm = m; } } if (incl_opts) { /* Timestamps. */ if (tp->t_flags & TF_RCVD_TSTMP) { to.to_tsval = tcp_ts_getticks() + tp->ts_offset; to.to_tsecr = tp->ts_recent; to.to_flags |= TOF_TS; } #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) /* TCP-MD5 (RFC2385). */ if (tp->t_flags & TF_SIGNATURE) to.to_flags |= TOF_SIGNATURE; #endif /* Add the options. */ tlen += optlen = tcp_addoptions(&to, optp); /* Update m_len in the correct mbuf. */ optm->m_len += optlen; } else optlen = 0; #ifdef INET6 if (isipv6) { if (uh) { ulen = tlen - sizeof(struct ip6_hdr); uh->uh_ulen = htons(ulen); } ip6->ip6_flow = htonl(ect << IPV6_FLOWLABEL_LEN); ip6->ip6_vfc = IPV6_VERSION; if (port) ip6->ip6_nxt = IPPROTO_UDP; else ip6->ip6_nxt = IPPROTO_TCP; ip6->ip6_plen = htons(tlen - sizeof(*ip6)); } #endif #if defined(INET) && defined(INET6) else #endif #ifdef INET { if (uh) { ulen = tlen - sizeof(struct ip); uh->uh_ulen = htons(ulen); } ip->ip_len = htons(tlen); if (inp != NULL) { ip->ip_tos = inp->inp_ip_tos & ~IPTOS_ECN_MASK; ip->ip_ttl = inp->inp_ip_ttl; } else { ip->ip_tos = 0; ip->ip_ttl = V_ip_defttl; } ip->ip_tos |= ect; if (port) { ip->ip_p = IPPROTO_UDP; } else { ip->ip_p = IPPROTO_TCP; } if (V_path_mtu_discovery) ip->ip_off |= htons(IP_DF); } #endif m->m_pkthdr.len = tlen; m->m_pkthdr.rcvif = NULL; #ifdef MAC if (inp != NULL) { /* * Packet is associated with a socket, so allow the * label of the response to reflect the socket label. */ INP_LOCK_ASSERT(inp); mac_inpcb_create_mbuf(inp, m); } else { /* * Packet is not associated with a socket, so possibly * update the label in place. */ mac_netinet_tcp_reply(m); } #endif nth->th_seq = htonl(seq); nth->th_ack = htonl(ack); nth->th_off = (sizeof (struct tcphdr) + optlen) >> 2; tcp_set_flags(nth, flags); if (tp && (flags & TH_RST)) { /* Log the reset */ tcp_log_end_status(tp, TCP_EI_STATUS_SERVER_RST); } if (tp != NULL) nth->th_win = htons((u_short) (win >> tp->rcv_scale)); else nth->th_win = htons((u_short)win); nth->th_urp = 0; #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) if (to.to_flags & TOF_SIGNATURE) { if (!TCPMD5_ENABLED() || TCPMD5_OUTPUT(m, nth, to.to_signature) != 0) { m_freem(m); return; } } #endif #ifdef INET6 if (isipv6) { if (port) { m->m_pkthdr.csum_flags = CSUM_UDP_IPV6; m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); uh->uh_sum = in6_cksum_pseudo(ip6, ulen, IPPROTO_UDP, 0); nth->th_sum = 0; } else { m->m_pkthdr.csum_flags = CSUM_TCP_IPV6; m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); nth->th_sum = in6_cksum_pseudo(ip6, tlen - sizeof(struct ip6_hdr), IPPROTO_TCP, 0); } ip6->ip6_hlim = in6_selecthlim(inp, NULL); } #endif /* INET6 */ #if defined(INET6) && defined(INET) else #endif #ifdef INET { if (port) { uh->uh_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, htons(ulen + IPPROTO_UDP)); m->m_pkthdr.csum_flags = CSUM_UDP; m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); nth->th_sum = 0; } else { m->m_pkthdr.csum_flags = CSUM_TCP; m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); nth->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, htons((u_short)(tlen - sizeof(struct ip) + ip->ip_p))); } } #endif /* INET */ TCP_PROBE3(debug__output, tp, th, m); if (flags & TH_RST) TCP_PROBE5(accept__refused, NULL, NULL, m, tp, nth); lgb = NULL; if ((tp != NULL) && tcp_bblogging_on(tp)) { if (INP_WLOCKED(inp)) { union tcp_log_stackspecific log; struct timeval tv; memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.inhpts = tcp_in_hpts(tp); log.u_bbr.flex8 = 4; log.u_bbr.pkts_out = tp->t_maxseg; log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.delivered = 0; lgb = tcp_log_event(tp, nth, NULL, NULL, TCP_LOG_OUT, ERRNO_UNK, 0, &log, false, NULL, NULL, 0, &tv); } else { /* * We can not log the packet, since we only own the * read lock, but a write lock is needed. The read lock * is not upgraded to a write lock, since only getting * the read lock was done intentionally to improve the * handling of SYN flooding attacks. * This happens only for pure SYN segments received in * the initial CLOSED state, or received in a more * advanced state than listen and the UDP encapsulation * port is unexpected. * The incoming SYN segments do not really belong to * the TCP connection and the handling does not change * the state of the TCP connection. Therefore, the * sending of the RST segments is not logged. Please * note that also the incoming SYN segments are not * logged. * * The following code ensures that the above description * is and stays correct. */ KASSERT((thflags & (TH_ACK|TH_SYN)) == TH_SYN && (tp->t_state == TCPS_CLOSED || (tp->t_state > TCPS_LISTEN && tp->t_port != port)), ("%s: Logging of TCP segment with flags 0x%b and " "UDP encapsulation port %u skipped in state %s", __func__, thflags, PRINT_TH_FLAGS, ntohs(port), tcpstates[tp->t_state])); } } if (flags & TH_ACK) TCPSTAT_INC(tcps_sndacks); else if (flags & (TH_SYN|TH_FIN|TH_RST)) TCPSTAT_INC(tcps_sndctrl); TCPSTAT_INC(tcps_sndtotal); #ifdef INET6 if (isipv6) { TCP_PROBE5(send, NULL, tp, ip6, tp, nth); output_ret = ip6_output(m, inp ? inp->in6p_outputopts : NULL, NULL, 0, NULL, NULL, inp); } #endif /* INET6 */ #if defined(INET) && defined(INET6) else #endif #ifdef INET { TCP_PROBE5(send, NULL, tp, ip, tp, nth); output_ret = ip_output(m, NULL, NULL, 0, NULL, inp); } #endif if (lgb != NULL) lgb->tlb_errno = output_ret; } /* * Send a challenge ack (no data, no SACK option), but not more than * V_tcp_ack_war_cnt per V_tcp_ack_war_time_window (per TCP connection). */ void tcp_send_challenge_ack(struct tcpcb *tp, struct tcphdr *th, struct mbuf *m) { sbintime_t now; bool send_challenge_ack; if (V_tcp_ack_war_time_window == 0 || V_tcp_ack_war_cnt == 0) { /* ACK war protection is disabled. */ send_challenge_ack = true; } else { /* Start new epoch, if the previous one is already over. */ now = getsbinuptime(); if (tp->t_challenge_ack_end < now) { tp->t_challenge_ack_cnt = 0; tp->t_challenge_ack_end = now + V_tcp_ack_war_time_window * SBT_1MS; } /* * Send a challenge ACK, if less than tcp_ack_war_cnt have been * sent in the current epoch. */ if (tp->t_challenge_ack_cnt < V_tcp_ack_war_cnt) { send_challenge_ack = true; tp->t_challenge_ack_cnt++; } else { send_challenge_ack = false; } } if (send_challenge_ack) { tcp_respond(tp, mtod(m, void *), th, m, tp->rcv_nxt, tp->snd_nxt, TH_ACK); tp->last_ack_sent = tp->rcv_nxt; } } /* * Create a new TCP control block, making an empty reassembly queue and hooking * it to the argument protocol control block. The `inp' parameter must have * come from the zone allocator set up by tcpcbstor declaration. * The caller can provide a pointer to a tcpcb of the listener to inherit the * TCP function block from the listener. */ struct tcpcb * tcp_newtcpcb(struct inpcb *inp, struct tcpcb *listening_tcb) { struct tcpcb *tp = intotcpcb(inp); #ifdef INET6 int isipv6 = (inp->inp_vflag & INP_IPV6) != 0; #endif /* INET6 */ /* * Historically allocation was done with M_ZERO. There is a lot of * code that rely on that. For now take safe approach and zero whole * tcpcb. This definitely can be optimized. */ bzero(&tp->t_start_zero, t_zero_size); /* Initialise cc_var struct for this tcpcb. */ tp->t_ccv.tp = tp; rw_rlock(&tcp_function_lock); if (listening_tcb != NULL) { INP_LOCK_ASSERT(tptoinpcb(listening_tcb)); KASSERT(listening_tcb->t_fb != NULL, ("tcp_newtcpcb: listening_tcb->t_fb is NULL")); if (listening_tcb->t_fb->tfb_flags & TCP_FUNC_BEING_REMOVED) { rw_runlock(&tcp_function_lock); return (NULL); } tp->t_fb = listening_tcb->t_fb; } else { tp->t_fb = V_tcp_func_set_ptr; } refcount_acquire(&tp->t_fb->tfb_refcnt); KASSERT((tp->t_fb->tfb_flags & TCP_FUNC_BEING_REMOVED) == 0, ("tcp_newtcpcb: using TFB being removed")); rw_runlock(&tcp_function_lock); CC_LIST_RLOCK(); if (listening_tcb != NULL) { if (CC_ALGO(listening_tcb)->flags & CC_MODULE_BEING_REMOVED) { CC_LIST_RUNLOCK(); if (tp->t_fb->tfb_tcp_fb_fini) (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); refcount_release(&tp->t_fb->tfb_refcnt); return (NULL); } CC_ALGO(tp) = CC_ALGO(listening_tcb); } else CC_ALGO(tp) = CC_DEFAULT_ALGO(); cc_refer(CC_ALGO(tp)); CC_LIST_RUNLOCK(); if (CC_ALGO(tp)->cb_init != NULL) if (CC_ALGO(tp)->cb_init(&tp->t_ccv, NULL) > 0) { cc_detach(tp); if (tp->t_fb->tfb_tcp_fb_fini) (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); refcount_release(&tp->t_fb->tfb_refcnt); return (NULL); } #ifdef TCP_HHOOK if (khelp_init_osd(HELPER_CLASS_TCP, &tp->t_osd)) { if (CC_ALGO(tp)->cb_destroy != NULL) CC_ALGO(tp)->cb_destroy(&tp->t_ccv); CC_DATA(tp) = NULL; cc_detach(tp); if (tp->t_fb->tfb_tcp_fb_fini) (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); refcount_release(&tp->t_fb->tfb_refcnt); return (NULL); } #endif TAILQ_INIT(&tp->t_segq); STAILQ_INIT(&tp->t_inqueue); tp->t_maxseg = #ifdef INET6 isipv6 ? V_tcp_v6mssdflt : #endif /* INET6 */ V_tcp_mssdflt; /* All mbuf queue/ack compress flags should be off */ tcp_lro_features_off(tp); tp->t_hpts_cpu = HPTS_CPU_NONE; tp->t_lro_cpu = HPTS_CPU_NONE; callout_init_rw(&tp->t_callout, &inp->inp_lock, CALLOUT_TRYLOCK | CALLOUT_RETURNUNLOCKED); for (int i = 0; i < TT_N; i++) tp->t_timers[i] = SBT_MAX; switch (V_tcp_do_rfc1323) { case 0: break; default: case 1: tp->t_flags = (TF_REQ_SCALE|TF_REQ_TSTMP); break; case 2: tp->t_flags = TF_REQ_SCALE; break; case 3: tp->t_flags = TF_REQ_TSTMP; break; } if (V_tcp_do_sack) tp->t_flags |= TF_SACK_PERMIT; TAILQ_INIT(&tp->snd_holes); /* * Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no * rtt estimate. Set rttvar so that srtt + 4 * rttvar gives * reasonable initial retransmit time. */ tp->t_srtt = TCPTV_SRTTBASE; tp->t_rttvar = ((tcp_rexmit_initial - TCPTV_SRTTBASE) << TCP_RTTVAR_SHIFT) / 4; tp->t_rttmin = tcp_rexmit_min; tp->t_rxtcur = tcp_rexmit_initial; tp->snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT; tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT; tp->t_rcvtime = ticks; /* We always start with ticks granularity */ tp->t_tmr_granularity = TCP_TMR_GRANULARITY_TICKS; /* * IPv4 TTL initialization is necessary for an IPv6 socket as well, * because the socket may be bound to an IPv6 wildcard address, * which may match an IPv4-mapped IPv6 address. */ inp->inp_ip_ttl = V_ip_defttl; #ifdef TCPPCAP /* * Init the TCP PCAP queues. */ tcp_pcap_tcpcb_init(tp); #endif #ifdef TCP_BLACKBOX /* Initialize the per-TCPCB log data. */ tcp_log_tcpcbinit(tp); #endif tp->t_pacing_rate = -1; if (tp->t_fb->tfb_tcp_fb_init) { if ((*tp->t_fb->tfb_tcp_fb_init)(tp, &tp->t_fb_ptr)) { if (CC_ALGO(tp)->cb_destroy != NULL) CC_ALGO(tp)->cb_destroy(&tp->t_ccv); CC_DATA(tp) = NULL; cc_detach(tp); #ifdef TCP_HHOOK khelp_destroy_osd(&tp->t_osd); #endif refcount_release(&tp->t_fb->tfb_refcnt); return (NULL); } } #ifdef STATS if (V_tcp_perconn_stats_enable == 1) tp->t_stats = stats_blob_alloc(V_tcp_perconn_stats_dflt_tpl, 0); #endif if (V_tcp_do_lrd) tp->t_flags |= TF_LRD; return (tp); } /* * Drop a TCP connection, reporting * the specified error. If connection is synchronized, * then send a RST to peer. */ struct tcpcb * tcp_drop(struct tcpcb *tp, int errno) { struct socket *so = tptosocket(tp); NET_EPOCH_ASSERT(); INP_WLOCK_ASSERT(tptoinpcb(tp)); if (TCPS_HAVERCVDSYN(tp->t_state)) { tcp_state_change(tp, TCPS_CLOSED); /* Don't use tcp_output() here due to possible recursion. */ (void)tcp_output_nodrop(tp); TCPSTAT_INC(tcps_drops); } else TCPSTAT_INC(tcps_conndrops); if (errno == ETIMEDOUT && tp->t_softerror) errno = tp->t_softerror; so->so_error = errno; return (tcp_close(tp)); } void tcp_discardcb(struct tcpcb *tp) { struct inpcb *inp = tptoinpcb(tp); struct socket *so = tptosocket(tp); struct mbuf *m; #ifdef INET6 bool isipv6 = (inp->inp_vflag & INP_IPV6) != 0; #endif INP_WLOCK_ASSERT(inp); MPASS(!callout_active(&tp->t_callout)); MPASS(TAILQ_EMPTY(&tp->snd_holes)); /* free the reassembly queue, if any */ tcp_reass_flush(tp); #ifdef TCP_OFFLOAD /* Disconnect offload device, if any. */ if (tp->t_flags & TF_TOE) tcp_offload_detach(tp); #endif #ifdef TCPPCAP /* Free the TCP PCAP queues. */ tcp_pcap_drain(&(tp->t_inpkts)); tcp_pcap_drain(&(tp->t_outpkts)); #endif /* Allow the CC algorithm to clean up after itself. */ if (CC_ALGO(tp)->cb_destroy != NULL) CC_ALGO(tp)->cb_destroy(&tp->t_ccv); CC_DATA(tp) = NULL; /* Detach from the CC algorithm */ cc_detach(tp); #ifdef TCP_HHOOK khelp_destroy_osd(&tp->t_osd); #endif #ifdef STATS stats_blob_destroy(tp->t_stats); #endif CC_ALGO(tp) = NULL; if ((m = STAILQ_FIRST(&tp->t_inqueue)) != NULL) { struct mbuf *prev; STAILQ_INIT(&tp->t_inqueue); STAILQ_FOREACH_FROM_SAFE(m, &tp->t_inqueue, m_stailqpkt, prev) m_freem(m); } TCPSTATES_DEC(tp->t_state); if (tp->t_fb->tfb_tcp_fb_fini) (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); MPASS(!tcp_in_hpts(tp)); #ifdef TCP_BLACKBOX tcp_log_tcpcbfini(tp); #endif /* * If we got enough samples through the srtt filter, * save the rtt and rttvar in the routing entry. * 'Enough' is arbitrarily defined as 4 rtt samples. * 4 samples is enough for the srtt filter to converge * to within enough % of the correct value; fewer samples * and we could save a bogus rtt. The danger is not high * as tcp quickly recovers from everything. * XXX: Works very well but needs some more statistics! * * XXXRRS: Updating must be after the stack fini() since * that may be converting some internal representation of * say srtt etc into the general one used by other stacks. * Lets also at least protect against the so being NULL * as RW stated below. */ if ((tp->t_rttupdated >= 4) && (so != NULL)) { struct hc_metrics_lite metrics; uint32_t ssthresh; bzero(&metrics, sizeof(metrics)); /* * Update the ssthresh always when the conditions below * are satisfied. This gives us better new start value * for the congestion avoidance for new connections. * ssthresh is only set if packet loss occurred on a session. * * XXXRW: 'so' may be NULL here, and/or socket buffer may be * being torn down. Ideally this code would not use 'so'. */ ssthresh = tp->snd_ssthresh; if (ssthresh != 0 && ssthresh < so->so_snd.sb_hiwat / 2) { /* * convert the limit from user data bytes to * packets then to packet data bytes. */ ssthresh = (ssthresh + tp->t_maxseg / 2) / tp->t_maxseg; if (ssthresh < 2) ssthresh = 2; ssthresh *= (tp->t_maxseg + #ifdef INET6 (isipv6 ? sizeof (struct ip6_hdr) + sizeof (struct tcphdr) : #endif sizeof (struct tcpiphdr) #ifdef INET6 ) #endif ); } else ssthresh = 0; metrics.rmx_ssthresh = ssthresh; metrics.rmx_rtt = tp->t_srtt; metrics.rmx_rttvar = tp->t_rttvar; metrics.rmx_cwnd = tp->snd_cwnd; metrics.rmx_sendpipe = 0; metrics.rmx_recvpipe = 0; tcp_hc_update(&inp->inp_inc, &metrics); } refcount_release(&tp->t_fb->tfb_refcnt); } /* * Attempt to close a TCP control block, marking it as dropped, and freeing * the socket if we hold the only reference. */ struct tcpcb * tcp_close(struct tcpcb *tp) { struct inpcb *inp = tptoinpcb(tp); struct socket *so = tptosocket(tp); INP_WLOCK_ASSERT(inp); #ifdef TCP_OFFLOAD if (tp->t_state == TCPS_LISTEN) tcp_offload_listen_stop(tp); #endif /* * This releases the TFO pending counter resource for TFO listen * sockets as well as passively-created TFO sockets that transition * from SYN_RECEIVED to CLOSED. */ if (tp->t_tfo_pending) { tcp_fastopen_decrement_counter(tp->t_tfo_pending); tp->t_tfo_pending = NULL; } tcp_timer_stop(tp); if (tp->t_fb->tfb_tcp_timer_stop_all != NULL) tp->t_fb->tfb_tcp_timer_stop_all(tp); in_pcbdrop(inp); TCPSTAT_INC(tcps_closed); if (tp->t_state != TCPS_CLOSED) tcp_state_change(tp, TCPS_CLOSED); KASSERT(inp->inp_socket != NULL, ("tcp_close: inp_socket NULL")); tcp_free_sackholes(tp); soisdisconnected(so); if (inp->inp_flags & INP_SOCKREF) { inp->inp_flags &= ~INP_SOCKREF; INP_WUNLOCK(inp); sorele(so); return (NULL); } return (tp); } /* * Notify a tcp user of an asynchronous error; * store error as soft error, but wake up user * (for now, won't do anything until can select for soft error). * * Do not wake up user since there currently is no mechanism for * reporting soft errors (yet - a kqueue filter may be added). */ static struct inpcb * tcp_notify(struct inpcb *inp, int error) { struct tcpcb *tp; INP_WLOCK_ASSERT(inp); tp = intotcpcb(inp); KASSERT(tp != NULL, ("tcp_notify: tp == NULL")); /* * Ignore some errors if we are hooked up. * If connection hasn't completed, has retransmitted several times, * and receives a second error, give up now. This is better * than waiting a long time to establish a connection that * can never complete. */ if (tp->t_state == TCPS_ESTABLISHED && (error == EHOSTUNREACH || error == ENETUNREACH || error == EHOSTDOWN)) { if (inp->inp_route.ro_nh) { NH_FREE(inp->inp_route.ro_nh); inp->inp_route.ro_nh = (struct nhop_object *)NULL; } return (inp); } else if (tp->t_state < TCPS_ESTABLISHED && tp->t_rxtshift > 3 && tp->t_softerror) { tp = tcp_drop(tp, error); if (tp != NULL) return (inp); else return (NULL); } else { tp->t_softerror = error; return (inp); } #if 0 wakeup( &so->so_timeo); sorwakeup(so); sowwakeup(so); #endif } static int tcp_pcblist(SYSCTL_HANDLER_ARGS) { struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, INPLOOKUP_RLOCKPCB); struct xinpgen xig; struct inpcb *inp; int error; if (req->newptr != NULL) return (EPERM); if (req->oldptr == NULL) { int n; n = V_tcbinfo.ipi_count + counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); n += imax(n / 8, 10); req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xtcpcb); return (0); } if ((error = sysctl_wire_old_buffer(req, 0)) != 0) return (error); bzero(&xig, sizeof(xig)); xig.xig_len = sizeof xig; xig.xig_count = V_tcbinfo.ipi_count + counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); xig.xig_gen = V_tcbinfo.ipi_gencnt; xig.xig_sogen = so_gencnt; error = SYSCTL_OUT(req, &xig, sizeof xig); if (error) return (error); error = syncache_pcblist(req); if (error) return (error); while ((inp = inp_next(&inpi)) != NULL) { if (inp->inp_gencnt <= xig.xig_gen && cr_canseeinpcb(req->td->td_ucred, inp) == 0) { struct xtcpcb xt; tcp_inptoxtp(inp, &xt); error = SYSCTL_OUT(req, &xt, sizeof xt); if (error) { INP_RUNLOCK(inp); break; } else continue; } } if (!error) { /* * Give the user an updated idea of our state. * If the generation differs from what we told * her before, she knows that something happened * while we were processing this request, and it * might be necessary to retry. */ xig.xig_gen = V_tcbinfo.ipi_gencnt; xig.xig_sogen = so_gencnt; xig.xig_count = V_tcbinfo.ipi_count + counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); error = SYSCTL_OUT(req, &xig, sizeof xig); } return (error); } SYSCTL_PROC(_net_inet_tcp, TCPCTL_PCBLIST, pcblist, CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_NEEDGIANT, NULL, 0, tcp_pcblist, "S,xtcpcb", "List of active TCP connections"); #ifdef INET static int tcp_getcred(SYSCTL_HANDLER_ARGS) { struct xucred xuc; struct sockaddr_in addrs[2]; struct epoch_tracker et; struct inpcb *inp; int error; error = priv_check(req->td, PRIV_NETINET_GETCRED); if (error) return (error); error = SYSCTL_IN(req, addrs, sizeof(addrs)); if (error) return (error); NET_EPOCH_ENTER(et); inp = in_pcblookup(&V_tcbinfo, addrs[1].sin_addr, addrs[1].sin_port, addrs[0].sin_addr, addrs[0].sin_port, INPLOOKUP_RLOCKPCB, NULL); NET_EPOCH_EXIT(et); if (inp != NULL) { if (error == 0) error = cr_canseeinpcb(req->td->td_ucred, inp); if (error == 0) cru2x(inp->inp_cred, &xuc); INP_RUNLOCK(inp); } else error = ENOENT; if (error == 0) error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); return (error); } SYSCTL_PROC(_net_inet_tcp, OID_AUTO, getcred, CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_NEEDGIANT, 0, 0, tcp_getcred, "S,xucred", "Get the xucred of a TCP connection"); #endif /* INET */ #ifdef INET6 static int tcp6_getcred(SYSCTL_HANDLER_ARGS) { struct epoch_tracker et; struct xucred xuc; struct sockaddr_in6 addrs[2]; struct inpcb *inp; int error; #ifdef INET int mapped = 0; #endif error = priv_check(req->td, PRIV_NETINET_GETCRED); if (error) return (error); error = SYSCTL_IN(req, addrs, sizeof(addrs)); if (error) return (error); if ((error = sa6_embedscope(&addrs[0], V_ip6_use_defzone)) != 0 || (error = sa6_embedscope(&addrs[1], V_ip6_use_defzone)) != 0) { return (error); } if (IN6_IS_ADDR_V4MAPPED(&addrs[0].sin6_addr)) { #ifdef INET if (IN6_IS_ADDR_V4MAPPED(&addrs[1].sin6_addr)) mapped = 1; else #endif return (EINVAL); } NET_EPOCH_ENTER(et); #ifdef INET if (mapped == 1) inp = in_pcblookup(&V_tcbinfo, *(struct in_addr *)&addrs[1].sin6_addr.s6_addr[12], addrs[1].sin6_port, *(struct in_addr *)&addrs[0].sin6_addr.s6_addr[12], addrs[0].sin6_port, INPLOOKUP_RLOCKPCB, NULL); else #endif inp = in6_pcblookup(&V_tcbinfo, &addrs[1].sin6_addr, addrs[1].sin6_port, &addrs[0].sin6_addr, addrs[0].sin6_port, INPLOOKUP_RLOCKPCB, NULL); NET_EPOCH_EXIT(et); if (inp != NULL) { if (error == 0) error = cr_canseeinpcb(req->td->td_ucred, inp); if (error == 0) cru2x(inp->inp_cred, &xuc); INP_RUNLOCK(inp); } else error = ENOENT; if (error == 0) error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); return (error); } SYSCTL_PROC(_net_inet6_tcp6, OID_AUTO, getcred, CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_NEEDGIANT, 0, 0, tcp6_getcred, "S,xucred", "Get the xucred of a TCP6 connection"); #endif /* INET6 */ #ifdef INET /* Path MTU to try next when a fragmentation-needed message is received. */ static inline int tcp_next_pmtu(const struct icmp *icp, const struct ip *ip) { int mtu = ntohs(icp->icmp_nextmtu); /* If no alternative MTU was proposed, try the next smaller one. */ if (!mtu) mtu = ip_next_mtu(ntohs(ip->ip_len), 1); if (mtu < V_tcp_minmss + sizeof(struct tcpiphdr)) mtu = V_tcp_minmss + sizeof(struct tcpiphdr); return (mtu); } static void tcp_ctlinput_with_port(struct icmp *icp, uint16_t port) { struct ip *ip; struct tcphdr *th; struct inpcb *inp; struct tcpcb *tp; struct inpcb *(*notify)(struct inpcb *, int); struct in_conninfo inc; tcp_seq icmp_tcp_seq; int errno, mtu; errno = icmp_errmap(icp); switch (errno) { case 0: return; case EMSGSIZE: notify = tcp_mtudisc_notify; break; case ECONNREFUSED: if (V_icmp_may_rst) notify = tcp_drop_syn_sent; else notify = tcp_notify; break; case EHOSTUNREACH: if (V_icmp_may_rst && icp->icmp_type == ICMP_TIMXCEED) notify = tcp_drop_syn_sent; else notify = tcp_notify; break; default: notify = tcp_notify; } ip = &icp->icmp_ip; th = (struct tcphdr *)((caddr_t)ip + (ip->ip_hl << 2)); icmp_tcp_seq = th->th_seq; inp = in_pcblookup(&V_tcbinfo, ip->ip_dst, th->th_dport, ip->ip_src, th->th_sport, INPLOOKUP_WLOCKPCB, NULL); if (inp != NULL) { tp = intotcpcb(inp); #ifdef TCP_OFFLOAD if (tp->t_flags & TF_TOE && errno == EMSGSIZE) { /* * MTU discovery for offloaded connections. Let * the TOE driver verify seq# and process it. */ mtu = tcp_next_pmtu(icp, ip); tcp_offload_pmtu_update(tp, icmp_tcp_seq, mtu); goto out; } #endif if (tp->t_port != port) goto out; if (SEQ_GEQ(ntohl(icmp_tcp_seq), tp->snd_una) && SEQ_LT(ntohl(icmp_tcp_seq), tp->snd_max)) { if (errno == EMSGSIZE) { /* * MTU discovery: we got a needfrag and * will potentially try a lower MTU. */ mtu = tcp_next_pmtu(icp, ip); /* * Only process the offered MTU if it * is smaller than the current one. */ if (mtu < tp->t_maxseg + sizeof(struct tcpiphdr)) { bzero(&inc, sizeof(inc)); inc.inc_faddr = ip->ip_dst; inc.inc_fibnum = inp->inp_inc.inc_fibnum; tcp_hc_updatemtu(&inc, mtu); inp = tcp_mtudisc(inp, mtu); } } else inp = (*notify)(inp, errno); } } else { bzero(&inc, sizeof(inc)); inc.inc_fport = th->th_dport; inc.inc_lport = th->th_sport; inc.inc_faddr = ip->ip_dst; inc.inc_laddr = ip->ip_src; syncache_unreach(&inc, icmp_tcp_seq, port); } out: if (inp != NULL) INP_WUNLOCK(inp); } static void tcp_ctlinput(struct icmp *icmp) { tcp_ctlinput_with_port(icmp, htons(0)); } static void tcp_ctlinput_viaudp(udp_tun_icmp_param_t param) { /* Its a tunneled TCP over UDP icmp */ struct icmp *icmp = param.icmp; struct ip *outer_ip, *inner_ip; struct udphdr *udp; struct tcphdr *th, ttemp; int i_hlen, o_len; uint16_t port; outer_ip = (struct ip *)((caddr_t)icmp - sizeof(struct ip)); inner_ip = &icmp->icmp_ip; i_hlen = inner_ip->ip_hl << 2; o_len = ntohs(outer_ip->ip_len); if (o_len < (sizeof(struct ip) + 8 + i_hlen + sizeof(struct udphdr) + offsetof(struct tcphdr, th_ack))) { /* Not enough data present */ return; } /* Ok lets strip out the inner udphdr header by copying up on top of it the tcp hdr */ udp = (struct udphdr *)(((caddr_t)inner_ip) + i_hlen); if (ntohs(udp->uh_sport) != V_tcp_udp_tunneling_port) { return; } port = udp->uh_dport; th = (struct tcphdr *)(udp + 1); memcpy(&ttemp, th, sizeof(struct tcphdr)); memcpy(udp, &ttemp, sizeof(struct tcphdr)); /* Now adjust down the size of the outer IP header */ o_len -= sizeof(struct udphdr); outer_ip->ip_len = htons(o_len); /* Now call in to the normal handling code */ tcp_ctlinput_with_port(icmp, port); } #endif /* INET */ #ifdef INET6 static inline int tcp6_next_pmtu(const struct icmp6_hdr *icmp6) { int mtu = ntohl(icmp6->icmp6_mtu); /* * If no alternative MTU was proposed, or the proposed MTU was too * small, set to the min. */ if (mtu < IPV6_MMTU) mtu = IPV6_MMTU - 8; /* XXXNP: what is the adjustment for? */ return (mtu); } static void tcp6_ctlinput_with_port(struct ip6ctlparam *ip6cp, uint16_t port) { struct in6_addr *dst; struct inpcb *(*notify)(struct inpcb *, int); struct ip6_hdr *ip6; struct mbuf *m; struct inpcb *inp; struct tcpcb *tp; struct icmp6_hdr *icmp6; struct in_conninfo inc; struct tcp_ports { uint16_t th_sport; uint16_t th_dport; } t_ports; tcp_seq icmp_tcp_seq; unsigned int mtu; unsigned int off; int errno; icmp6 = ip6cp->ip6c_icmp6; m = ip6cp->ip6c_m; ip6 = ip6cp->ip6c_ip6; off = ip6cp->ip6c_off; dst = &ip6cp->ip6c_finaldst->sin6_addr; errno = icmp6_errmap(icmp6); switch (errno) { case 0: return; case EMSGSIZE: notify = tcp_mtudisc_notify; break; case ECONNREFUSED: if (V_icmp_may_rst) notify = tcp_drop_syn_sent; else notify = tcp_notify; break; case EHOSTUNREACH: /* * There are only four ICMPs that may reset connection: * - administratively prohibited * - port unreachable * - time exceeded in transit * - unknown next header */ if (V_icmp_may_rst && ((icmp6->icmp6_type == ICMP6_DST_UNREACH && (icmp6->icmp6_code == ICMP6_DST_UNREACH_ADMIN || icmp6->icmp6_code == ICMP6_DST_UNREACH_NOPORT)) || (icmp6->icmp6_type == ICMP6_TIME_EXCEEDED && icmp6->icmp6_code == ICMP6_TIME_EXCEED_TRANSIT) || (icmp6->icmp6_type == ICMP6_PARAM_PROB && icmp6->icmp6_code == ICMP6_PARAMPROB_NEXTHEADER))) notify = tcp_drop_syn_sent; else notify = tcp_notify; break; default: notify = tcp_notify; } /* Check if we can safely get the ports from the tcp hdr */ if (m == NULL || (m->m_pkthdr.len < (int32_t) (off + sizeof(struct tcp_ports)))) { return; } bzero(&t_ports, sizeof(struct tcp_ports)); m_copydata(m, off, sizeof(struct tcp_ports), (caddr_t)&t_ports); inp = in6_pcblookup(&V_tcbinfo, &ip6->ip6_dst, t_ports.th_dport, &ip6->ip6_src, t_ports.th_sport, INPLOOKUP_WLOCKPCB, NULL); off += sizeof(struct tcp_ports); if (m->m_pkthdr.len < (int32_t) (off + sizeof(tcp_seq))) { goto out; } m_copydata(m, off, sizeof(tcp_seq), (caddr_t)&icmp_tcp_seq); if (inp != NULL) { tp = intotcpcb(inp); #ifdef TCP_OFFLOAD if (tp->t_flags & TF_TOE && errno == EMSGSIZE) { /* MTU discovery for offloaded connections. */ mtu = tcp6_next_pmtu(icmp6); tcp_offload_pmtu_update(tp, icmp_tcp_seq, mtu); goto out; } #endif if (tp->t_port != port) goto out; if (SEQ_GEQ(ntohl(icmp_tcp_seq), tp->snd_una) && SEQ_LT(ntohl(icmp_tcp_seq), tp->snd_max)) { if (errno == EMSGSIZE) { /* * MTU discovery: * If we got a needfrag set the MTU * in the route to the suggested new * value (if given) and then notify. */ mtu = tcp6_next_pmtu(icmp6); bzero(&inc, sizeof(inc)); inc.inc_fibnum = M_GETFIB(m); inc.inc_flags |= INC_ISIPV6; inc.inc6_faddr = *dst; if (in6_setscope(&inc.inc6_faddr, m->m_pkthdr.rcvif, NULL)) goto out; /* * Only process the offered MTU if it * is smaller than the current one. */ if (mtu < tp->t_maxseg + sizeof (struct tcphdr) + sizeof (struct ip6_hdr)) { tcp_hc_updatemtu(&inc, mtu); tcp_mtudisc(inp, mtu); ICMP6STAT_INC(icp6s_pmtuchg); } } else inp = (*notify)(inp, errno); } } else { bzero(&inc, sizeof(inc)); inc.inc_fibnum = M_GETFIB(m); inc.inc_flags |= INC_ISIPV6; inc.inc_fport = t_ports.th_dport; inc.inc_lport = t_ports.th_sport; inc.inc6_faddr = *dst; inc.inc6_laddr = ip6->ip6_src; syncache_unreach(&inc, icmp_tcp_seq, port); } out: if (inp != NULL) INP_WUNLOCK(inp); } static void tcp6_ctlinput(struct ip6ctlparam *ctl) { tcp6_ctlinput_with_port(ctl, htons(0)); } static void tcp6_ctlinput_viaudp(udp_tun_icmp_param_t param) { struct ip6ctlparam *ip6cp = param.ip6cp; struct mbuf *m; struct udphdr *udp; uint16_t port; m = m_pulldown(ip6cp->ip6c_m, ip6cp->ip6c_off, sizeof(struct udphdr), NULL); if (m == NULL) { return; } udp = mtod(m, struct udphdr *); if (ntohs(udp->uh_sport) != V_tcp_udp_tunneling_port) { return; } port = udp->uh_dport; m_adj(m, sizeof(struct udphdr)); if ((m->m_flags & M_PKTHDR) == 0) { ip6cp->ip6c_m->m_pkthdr.len -= sizeof(struct udphdr); } /* Now call in to the normal handling code */ tcp6_ctlinput_with_port(ip6cp, port); } #endif /* INET6 */ static uint32_t tcp_keyed_hash(struct in_conninfo *inc, u_char *key, u_int len) { SIPHASH_CTX ctx; uint32_t hash[2]; KASSERT(len >= SIPHASH_KEY_LENGTH, ("%s: keylen %u too short ", __func__, len)); SipHash24_Init(&ctx); SipHash_SetKey(&ctx, (uint8_t *)key); SipHash_Update(&ctx, &inc->inc_fport, sizeof(uint16_t)); SipHash_Update(&ctx, &inc->inc_lport, sizeof(uint16_t)); switch (inc->inc_flags & INC_ISIPV6) { #ifdef INET case 0: SipHash_Update(&ctx, &inc->inc_faddr, sizeof(struct in_addr)); SipHash_Update(&ctx, &inc->inc_laddr, sizeof(struct in_addr)); break; #endif #ifdef INET6 case INC_ISIPV6: SipHash_Update(&ctx, &inc->inc6_faddr, sizeof(struct in6_addr)); SipHash_Update(&ctx, &inc->inc6_laddr, sizeof(struct in6_addr)); break; #endif } SipHash_Final((uint8_t *)hash, &ctx); return (hash[0] ^ hash[1]); } uint32_t tcp_new_ts_offset(struct in_conninfo *inc) { struct in_conninfo inc_store, *local_inc; if (!V_tcp_ts_offset_per_conn) { memcpy(&inc_store, inc, sizeof(struct in_conninfo)); inc_store.inc_lport = 0; inc_store.inc_fport = 0; local_inc = &inc_store; } else { local_inc = inc; } return (tcp_keyed_hash(local_inc, V_ts_offset_secret, sizeof(V_ts_offset_secret))); } /* * Following is where TCP initial sequence number generation occurs. * * There are two places where we must use initial sequence numbers: * 1. In SYN-ACK packets. * 2. In SYN packets. * * All ISNs for SYN-ACK packets are generated by the syncache. See * tcp_syncache.c for details. * * The ISNs in SYN packets must be monotonic; TIME_WAIT recycling * depends on this property. In addition, these ISNs should be * unguessable so as to prevent connection hijacking. To satisfy * the requirements of this situation, the algorithm outlined in * RFC 1948 is used, with only small modifications. * * Implementation details: * * Time is based off the system timer, and is corrected so that it * increases by one megabyte per second. This allows for proper * recycling on high speed LANs while still leaving over an hour * before rollover. * * As reading the *exact* system time is too expensive to be done * whenever setting up a TCP connection, we increment the time * offset in two ways. First, a small random positive increment * is added to isn_offset for each connection that is set up. * Second, the function tcp_isn_tick fires once per clock tick * and increments isn_offset as necessary so that sequence numbers * are incremented at approximately ISN_BYTES_PER_SECOND. The * random positive increments serve only to ensure that the same * exact sequence number is never sent out twice (as could otherwise * happen when a port is recycled in less than the system tick * interval.) * * net.inet.tcp.isn_reseed_interval controls the number of seconds * between seeding of isn_secret. This is normally set to zero, * as reseeding should not be necessary. * * Locking of the global variables isn_secret, isn_last_reseed, isn_offset, * isn_offset_old, and isn_ctx is performed using the ISN lock. In * general, this means holding an exclusive (write) lock. */ #define ISN_BYTES_PER_SECOND 1048576 #define ISN_STATIC_INCREMENT 4096 #define ISN_RANDOM_INCREMENT (4096 - 1) #define ISN_SECRET_LENGTH SIPHASH_KEY_LENGTH VNET_DEFINE_STATIC(u_char, isn_secret[ISN_SECRET_LENGTH]); VNET_DEFINE_STATIC(int, isn_last); VNET_DEFINE_STATIC(int, isn_last_reseed); VNET_DEFINE_STATIC(u_int32_t, isn_offset); VNET_DEFINE_STATIC(u_int32_t, isn_offset_old); #define V_isn_secret VNET(isn_secret) #define V_isn_last VNET(isn_last) #define V_isn_last_reseed VNET(isn_last_reseed) #define V_isn_offset VNET(isn_offset) #define V_isn_offset_old VNET(isn_offset_old) tcp_seq tcp_new_isn(struct in_conninfo *inc) { tcp_seq new_isn; u_int32_t projected_offset; ISN_LOCK(); /* Seed if this is the first use, reseed if requested. */ if ((V_isn_last_reseed == 0) || ((V_tcp_isn_reseed_interval > 0) && (((u_int)V_isn_last_reseed + (u_int)V_tcp_isn_reseed_interval*hz) < (u_int)ticks))) { arc4rand(&V_isn_secret, sizeof(V_isn_secret), 0); V_isn_last_reseed = ticks; } /* Compute the hash and return the ISN. */ new_isn = (tcp_seq)tcp_keyed_hash(inc, V_isn_secret, sizeof(V_isn_secret)); V_isn_offset += ISN_STATIC_INCREMENT + (arc4random() & ISN_RANDOM_INCREMENT); if (ticks != V_isn_last) { projected_offset = V_isn_offset_old + ISN_BYTES_PER_SECOND / hz * (ticks - V_isn_last); if (SEQ_GT(projected_offset, V_isn_offset)) V_isn_offset = projected_offset; V_isn_offset_old = V_isn_offset; V_isn_last = ticks; } new_isn += V_isn_offset; ISN_UNLOCK(); return (new_isn); } /* * When a specific ICMP unreachable message is received and the * connection state is SYN-SENT, drop the connection. This behavior * is controlled by the icmp_may_rst sysctl. */ static struct inpcb * tcp_drop_syn_sent(struct inpcb *inp, int errno) { struct tcpcb *tp; NET_EPOCH_ASSERT(); INP_WLOCK_ASSERT(inp); tp = intotcpcb(inp); if (tp->t_state != TCPS_SYN_SENT) return (inp); if (tp->t_flags & TF_FASTOPEN) tcp_fastopen_disable_path(tp); tp = tcp_drop(tp, errno); if (tp != NULL) return (inp); else return (NULL); } /* * When `need fragmentation' ICMP is received, update our idea of the MSS * based on the new value. Also nudge TCP to send something, since we * know the packet we just sent was dropped. * This duplicates some code in the tcp_mss() function in tcp_input.c. */ static struct inpcb * tcp_mtudisc_notify(struct inpcb *inp, int error) { return (tcp_mtudisc(inp, -1)); } static struct inpcb * tcp_mtudisc(struct inpcb *inp, int mtuoffer) { struct tcpcb *tp; struct socket *so; INP_WLOCK_ASSERT(inp); tp = intotcpcb(inp); KASSERT(tp != NULL, ("tcp_mtudisc: tp == NULL")); tcp_mss_update(tp, -1, mtuoffer, NULL, NULL); so = inp->inp_socket; - SOCKBUF_LOCK(&so->so_snd); + SOCK_SENDBUF_LOCK(so); /* If the mss is larger than the socket buffer, decrease the mss. */ if (so->so_snd.sb_hiwat < tp->t_maxseg) { tp->t_maxseg = so->so_snd.sb_hiwat; if (tp->t_maxseg < V_tcp_mssdflt) { /* * The MSS is so small we should not process incoming * SACK's since we are subject to attack in such a * case. */ tp->t_flags2 |= TF2_PROC_SACK_PROHIBIT; } else { tp->t_flags2 &= ~TF2_PROC_SACK_PROHIBIT; } } - SOCKBUF_UNLOCK(&so->so_snd); + SOCK_SENDBUF_UNLOCK(so); TCPSTAT_INC(tcps_mturesent); tp->t_rtttime = 0; tp->snd_nxt = tp->snd_una; tcp_free_sackholes(tp); tp->snd_recover = tp->snd_max; if (tp->t_flags & TF_SACK_PERMIT) EXIT_FASTRECOVERY(tp->t_flags); if (tp->t_fb->tfb_tcp_mtu_chg != NULL) { /* * Conceptually the snd_nxt setting * and freeing sack holes should * be done by the default stacks * own tfb_tcp_mtu_chg(). */ tp->t_fb->tfb_tcp_mtu_chg(tp); } if (tcp_output(tp) < 0) return (NULL); else return (inp); } #ifdef INET /* * Look-up the routing entry to the peer of this inpcb. If no route * is found and it cannot be allocated, then return 0. This routine * is called by TCP routines that access the rmx structure and by * tcp_mss_update to get the peer/interface MTU. */ uint32_t tcp_maxmtu(struct in_conninfo *inc, struct tcp_ifcap *cap) { struct nhop_object *nh; struct ifnet *ifp; uint32_t maxmtu = 0; KASSERT(inc != NULL, ("tcp_maxmtu with NULL in_conninfo pointer")); if (inc->inc_faddr.s_addr != INADDR_ANY) { nh = fib4_lookup(inc->inc_fibnum, inc->inc_faddr, 0, NHR_NONE, 0); if (nh == NULL) return (0); ifp = nh->nh_ifp; maxmtu = nh->nh_mtu; /* Report additional interface capabilities. */ if (cap != NULL) { if (ifp->if_capenable & IFCAP_TSO4 && ifp->if_hwassist & CSUM_TSO) { cap->ifcap |= CSUM_TSO; cap->tsomax = ifp->if_hw_tsomax; cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount; cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize; /* XXXKIB IFCAP2_IPSEC_OFFLOAD_TSO */ cap->ipsec_tso = (ifp->if_capenable2 & IFCAP2_BIT(IFCAP2_IPSEC_OFFLOAD)) != 0; } } } return (maxmtu); } #endif /* INET */ #ifdef INET6 uint32_t tcp_maxmtu6(struct in_conninfo *inc, struct tcp_ifcap *cap) { struct nhop_object *nh; struct in6_addr dst6; uint32_t scopeid; struct ifnet *ifp; uint32_t maxmtu = 0; KASSERT(inc != NULL, ("tcp_maxmtu6 with NULL in_conninfo pointer")); if (inc->inc_flags & INC_IPV6MINMTU) return (IPV6_MMTU); if (!IN6_IS_ADDR_UNSPECIFIED(&inc->inc6_faddr)) { in6_splitscope(&inc->inc6_faddr, &dst6, &scopeid); nh = fib6_lookup(inc->inc_fibnum, &dst6, scopeid, NHR_NONE, 0); if (nh == NULL) return (0); ifp = nh->nh_ifp; maxmtu = nh->nh_mtu; /* Report additional interface capabilities. */ if (cap != NULL) { if (ifp->if_capenable & IFCAP_TSO6 && ifp->if_hwassist & CSUM_TSO) { cap->ifcap |= CSUM_TSO; cap->tsomax = ifp->if_hw_tsomax; cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount; cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize; cap->ipsec_tso = false; /* XXXKIB */ } } } return (maxmtu); } /* * Handle setsockopt(IPV6_USE_MIN_MTU) by a TCP stack. * * XXXGL: we are updating inpcb here with INC_IPV6MINMTU flag. * The right place to do that is ip6_setpktopt() that has just been * executed. By the way it just filled ip6po_minmtu for us. */ void tcp6_use_min_mtu(struct tcpcb *tp) { struct inpcb *inp = tptoinpcb(tp); INP_WLOCK_ASSERT(inp); /* * In case of the IPV6_USE_MIN_MTU socket * option, the INC_IPV6MINMTU flag to announce * a corresponding MSS during the initial * handshake. If the TCP connection is not in * the front states, just reduce the MSS being * used. This avoids the sending of TCP * segments which will be fragmented at the * IPv6 layer. */ inp->inp_inc.inc_flags |= INC_IPV6MINMTU; if ((tp->t_state >= TCPS_SYN_SENT) && (inp->inp_inc.inc_flags & INC_ISIPV6)) { struct ip6_pktopts *opt; opt = inp->in6p_outputopts; if (opt != NULL && opt->ip6po_minmtu == IP6PO_MINMTU_ALL && tp->t_maxseg > TCP6_MSS) { tp->t_maxseg = TCP6_MSS; if (tp->t_maxseg < V_tcp_mssdflt) { /* * The MSS is so small we should not process incoming * SACK's since we are subject to attack in such a * case. */ tp->t_flags2 |= TF2_PROC_SACK_PROHIBIT; } else { tp->t_flags2 &= ~TF2_PROC_SACK_PROHIBIT; } } } } #endif /* INET6 */ /* * Calculate effective SMSS per RFC5681 definition for a given TCP * connection at its current state, taking into account SACK and etc. */ u_int tcp_maxseg(const struct tcpcb *tp) { u_int optlen; if (tp->t_flags & TF_NOOPT) return (tp->t_maxseg); /* * Here we have a simplified code from tcp_addoptions(), * without a proper loop, and having most of paddings hardcoded. * We might make mistakes with padding here in some edge cases, * but this is harmless, since result of tcp_maxseg() is used * only in cwnd and ssthresh estimations. */ if (TCPS_HAVEESTABLISHED(tp->t_state)) { if (tp->t_flags & TF_RCVD_TSTMP) optlen = TCPOLEN_TSTAMP_APPA; else optlen = 0; #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) if (tp->t_flags & TF_SIGNATURE) optlen += PADTCPOLEN(TCPOLEN_SIGNATURE); #endif if ((tp->t_flags & TF_SACK_PERMIT) && tp->rcv_numsacks > 0) { optlen += TCPOLEN_SACKHDR; optlen += tp->rcv_numsacks * TCPOLEN_SACK; optlen = PADTCPOLEN(optlen); } } else { if (tp->t_flags & TF_REQ_TSTMP) optlen = TCPOLEN_TSTAMP_APPA; else optlen = PADTCPOLEN(TCPOLEN_MAXSEG); if (tp->t_flags & TF_REQ_SCALE) optlen += PADTCPOLEN(TCPOLEN_WINDOW); #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) if (tp->t_flags & TF_SIGNATURE) optlen += PADTCPOLEN(TCPOLEN_SIGNATURE); #endif if (tp->t_flags & TF_SACK_PERMIT) optlen += PADTCPOLEN(TCPOLEN_SACK_PERMITTED); } optlen = min(optlen, TCP_MAXOLEN); return (tp->t_maxseg - optlen); } u_int tcp_fixed_maxseg(const struct tcpcb *tp) { int optlen; if (tp->t_flags & TF_NOOPT) return (tp->t_maxseg); /* * Here we have a simplified code from tcp_addoptions(), * without a proper loop, and having most of paddings hardcoded. * We only consider fixed options that we would send every * time I.e. SACK is not considered. This is important * for cc modules to figure out what the modulo of the * cwnd should be. */ if (TCPS_HAVEESTABLISHED(tp->t_state)) { if (tp->t_flags & TF_RCVD_TSTMP) optlen = TCPOLEN_TSTAMP_APPA; else optlen = 0; #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) if (tp->t_flags & TF_SIGNATURE) optlen += PADTCPOLEN(TCPOLEN_SIGNATURE); #endif } else { if (tp->t_flags & TF_REQ_TSTMP) optlen = TCPOLEN_TSTAMP_APPA; else optlen = PADTCPOLEN(TCPOLEN_MAXSEG); if (tp->t_flags & TF_REQ_SCALE) optlen += PADTCPOLEN(TCPOLEN_WINDOW); #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) if (tp->t_flags & TF_SIGNATURE) optlen += PADTCPOLEN(TCPOLEN_SIGNATURE); #endif if (tp->t_flags & TF_SACK_PERMIT) optlen += PADTCPOLEN(TCPOLEN_SACK_PERMITTED); } optlen = min(optlen, TCP_MAXOLEN); return (tp->t_maxseg - optlen); } static int sysctl_drop(SYSCTL_HANDLER_ARGS) { /* addrs[0] is a foreign socket, addrs[1] is a local one. */ struct sockaddr_storage addrs[2]; struct inpcb *inp; struct tcpcb *tp; #ifdef INET struct sockaddr_in *fin = NULL, *lin = NULL; #endif struct epoch_tracker et; #ifdef INET6 struct sockaddr_in6 *fin6, *lin6; #endif int error; inp = NULL; #ifdef INET6 fin6 = lin6 = NULL; #endif error = 0; if (req->oldptr != NULL || req->oldlen != 0) return (EINVAL); if (req->newptr == NULL) return (EPERM); if (req->newlen < sizeof(addrs)) return (ENOMEM); error = SYSCTL_IN(req, &addrs, sizeof(addrs)); if (error) return (error); switch (addrs[0].ss_family) { #ifdef INET6 case AF_INET6: fin6 = (struct sockaddr_in6 *)&addrs[0]; lin6 = (struct sockaddr_in6 *)&addrs[1]; if (fin6->sin6_len != sizeof(struct sockaddr_in6) || lin6->sin6_len != sizeof(struct sockaddr_in6)) return (EINVAL); if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr)) { if (!IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr)) return (EINVAL); in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[0]); in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[1]); #ifdef INET fin = (struct sockaddr_in *)&addrs[0]; lin = (struct sockaddr_in *)&addrs[1]; #endif break; } error = sa6_embedscope(fin6, V_ip6_use_defzone); if (error) return (error); error = sa6_embedscope(lin6, V_ip6_use_defzone); if (error) return (error); break; #endif #ifdef INET case AF_INET: fin = (struct sockaddr_in *)&addrs[0]; lin = (struct sockaddr_in *)&addrs[1]; if (fin->sin_len != sizeof(struct sockaddr_in) || lin->sin_len != sizeof(struct sockaddr_in)) return (EINVAL); break; #endif default: return (EINVAL); } NET_EPOCH_ENTER(et); switch (addrs[0].ss_family) { #ifdef INET6 case AF_INET6: inp = in6_pcblookup(&V_tcbinfo, &fin6->sin6_addr, fin6->sin6_port, &lin6->sin6_addr, lin6->sin6_port, INPLOOKUP_WLOCKPCB, NULL); break; #endif #ifdef INET case AF_INET: inp = in_pcblookup(&V_tcbinfo, fin->sin_addr, fin->sin_port, lin->sin_addr, lin->sin_port, INPLOOKUP_WLOCKPCB, NULL); break; #endif } if (inp != NULL) { if (!SOLISTENING(inp->inp_socket)) { tp = intotcpcb(inp); tp = tcp_drop(tp, ECONNABORTED); if (tp != NULL) INP_WUNLOCK(inp); } else INP_WUNLOCK(inp); } else error = ESRCH; NET_EPOCH_EXIT(et); return (error); } SYSCTL_PROC(_net_inet_tcp, TCPCTL_DROP, drop, CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | CTLFLAG_NEEDGIANT, NULL, 0, sysctl_drop, "", "Drop TCP connection"); static int tcp_sysctl_setsockopt(SYSCTL_HANDLER_ARGS) { return (sysctl_setsockopt(oidp, arg1, arg2, req, &V_tcbinfo, &tcp_ctloutput_set)); } SYSCTL_PROC(_net_inet_tcp, OID_AUTO, setsockopt, CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | CTLFLAG_MPSAFE, NULL, 0, tcp_sysctl_setsockopt, "", "Set socket option for TCP endpoint"); #ifdef KERN_TLS static int sysctl_switch_tls(SYSCTL_HANDLER_ARGS) { /* addrs[0] is a foreign socket, addrs[1] is a local one. */ struct sockaddr_storage addrs[2]; struct inpcb *inp; #ifdef INET struct sockaddr_in *fin = NULL, *lin = NULL; #endif struct epoch_tracker et; #ifdef INET6 struct sockaddr_in6 *fin6, *lin6; #endif int error; inp = NULL; #ifdef INET6 fin6 = lin6 = NULL; #endif error = 0; if (req->oldptr != NULL || req->oldlen != 0) return (EINVAL); if (req->newptr == NULL) return (EPERM); if (req->newlen < sizeof(addrs)) return (ENOMEM); error = SYSCTL_IN(req, &addrs, sizeof(addrs)); if (error) return (error); switch (addrs[0].ss_family) { #ifdef INET6 case AF_INET6: fin6 = (struct sockaddr_in6 *)&addrs[0]; lin6 = (struct sockaddr_in6 *)&addrs[1]; if (fin6->sin6_len != sizeof(struct sockaddr_in6) || lin6->sin6_len != sizeof(struct sockaddr_in6)) return (EINVAL); if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr)) { if (!IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr)) return (EINVAL); in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[0]); in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[1]); #ifdef INET fin = (struct sockaddr_in *)&addrs[0]; lin = (struct sockaddr_in *)&addrs[1]; #endif break; } error = sa6_embedscope(fin6, V_ip6_use_defzone); if (error) return (error); error = sa6_embedscope(lin6, V_ip6_use_defzone); if (error) return (error); break; #endif #ifdef INET case AF_INET: fin = (struct sockaddr_in *)&addrs[0]; lin = (struct sockaddr_in *)&addrs[1]; if (fin->sin_len != sizeof(struct sockaddr_in) || lin->sin_len != sizeof(struct sockaddr_in)) return (EINVAL); break; #endif default: return (EINVAL); } NET_EPOCH_ENTER(et); switch (addrs[0].ss_family) { #ifdef INET6 case AF_INET6: inp = in6_pcblookup(&V_tcbinfo, &fin6->sin6_addr, fin6->sin6_port, &lin6->sin6_addr, lin6->sin6_port, INPLOOKUP_WLOCKPCB, NULL); break; #endif #ifdef INET case AF_INET: inp = in_pcblookup(&V_tcbinfo, fin->sin_addr, fin->sin_port, lin->sin_addr, lin->sin_port, INPLOOKUP_WLOCKPCB, NULL); break; #endif } NET_EPOCH_EXIT(et); if (inp != NULL) { struct socket *so; so = inp->inp_socket; soref(so); error = ktls_set_tx_mode(so, arg2 == 0 ? TCP_TLS_MODE_SW : TCP_TLS_MODE_IFNET); INP_WUNLOCK(inp); sorele(so); } else error = ESRCH; return (error); } SYSCTL_PROC(_net_inet_tcp, OID_AUTO, switch_to_sw_tls, CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | CTLFLAG_NEEDGIANT, NULL, 0, sysctl_switch_tls, "", "Switch TCP connection to SW TLS"); SYSCTL_PROC(_net_inet_tcp, OID_AUTO, switch_to_ifnet_tls, CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | CTLFLAG_NEEDGIANT, NULL, 1, sysctl_switch_tls, "", "Switch TCP connection to ifnet TLS"); #endif /* * Generate a standardized TCP log line for use throughout the * tcp subsystem. Memory allocation is done with M_NOWAIT to * allow use in the interrupt context. * * NB: The caller MUST free(s, M_TCPLOG) the returned string. * NB: The function may return NULL if memory allocation failed. * * Due to header inclusion and ordering limitations the struct ip * and ip6_hdr pointers have to be passed as void pointers. */ char * tcp_log_vain(struct in_conninfo *inc, struct tcphdr *th, const void *ip4hdr, const void *ip6hdr) { /* Is logging enabled? */ if (V_tcp_log_in_vain == 0) return (NULL); return (tcp_log_addr(inc, th, ip4hdr, ip6hdr)); } char * tcp_log_addrs(struct in_conninfo *inc, struct tcphdr *th, const void *ip4hdr, const void *ip6hdr) { /* Is logging enabled? */ if (tcp_log_debug == 0) return (NULL); return (tcp_log_addr(inc, th, ip4hdr, ip6hdr)); } static char * tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th, const void *ip4hdr, const void *ip6hdr) { char *s, *sp; size_t size; #ifdef INET const struct ip *ip = (const struct ip *)ip4hdr; #endif #ifdef INET6 const struct ip6_hdr *ip6 = (const struct ip6_hdr *)ip6hdr; #endif /* INET6 */ /* * The log line looks like this: * "TCP: [1.2.3.4]:50332 to [1.2.3.4]:80 tcpflags 0x2" */ size = sizeof("TCP: []:12345 to []:12345 tcpflags 0x2<>") + sizeof(PRINT_TH_FLAGS) + 1 + #ifdef INET6 2 * INET6_ADDRSTRLEN; #else 2 * INET_ADDRSTRLEN; #endif /* INET6 */ s = malloc(size, M_TCPLOG, M_ZERO|M_NOWAIT); if (s == NULL) return (NULL); strcat(s, "TCP: ["); sp = s + strlen(s); if (inc && ((inc->inc_flags & INC_ISIPV6) == 0)) { inet_ntoa_r(inc->inc_faddr, sp); sp = s + strlen(s); sprintf(sp, "]:%i to [", ntohs(inc->inc_fport)); sp = s + strlen(s); inet_ntoa_r(inc->inc_laddr, sp); sp = s + strlen(s); sprintf(sp, "]:%i", ntohs(inc->inc_lport)); #ifdef INET6 } else if (inc) { ip6_sprintf(sp, &inc->inc6_faddr); sp = s + strlen(s); sprintf(sp, "]:%i to [", ntohs(inc->inc_fport)); sp = s + strlen(s); ip6_sprintf(sp, &inc->inc6_laddr); sp = s + strlen(s); sprintf(sp, "]:%i", ntohs(inc->inc_lport)); } else if (ip6 && th) { ip6_sprintf(sp, &ip6->ip6_src); sp = s + strlen(s); sprintf(sp, "]:%i to [", ntohs(th->th_sport)); sp = s + strlen(s); ip6_sprintf(sp, &ip6->ip6_dst); sp = s + strlen(s); sprintf(sp, "]:%i", ntohs(th->th_dport)); #endif /* INET6 */ #ifdef INET } else if (ip && th) { inet_ntoa_r(ip->ip_src, sp); sp = s + strlen(s); sprintf(sp, "]:%i to [", ntohs(th->th_sport)); sp = s + strlen(s); inet_ntoa_r(ip->ip_dst, sp); sp = s + strlen(s); sprintf(sp, "]:%i", ntohs(th->th_dport)); #endif /* INET */ } else { free(s, M_TCPLOG); return (NULL); } sp = s + strlen(s); if (th) sprintf(sp, " tcpflags 0x%b", tcp_get_flags(th), PRINT_TH_FLAGS); if (*(s + size - 1) != '\0') panic("%s: string too long", __func__); return (s); } /* * A subroutine which makes it easy to track TCP state changes with DTrace. * This function shouldn't be called for t_state initializations that don't * correspond to actual TCP state transitions. */ void tcp_state_change(struct tcpcb *tp, int newstate) { #if defined(KDTRACE_HOOKS) int pstate = tp->t_state; #endif TCPSTATES_DEC(tp->t_state); TCPSTATES_INC(newstate); tp->t_state = newstate; TCP_PROBE6(state__change, NULL, tp, NULL, tp, NULL, pstate); } /* * Create an external-format (``xtcpcb'') structure using the information in * the kernel-format tcpcb structure pointed to by tp. This is done to * reduce the spew of irrelevant information over this interface, to isolate * user code from changes in the kernel structure, and potentially to provide * information-hiding if we decide that some of this information should be * hidden from users. */ void tcp_inptoxtp(const struct inpcb *inp, struct xtcpcb *xt) { struct tcpcb *tp = intotcpcb(inp); sbintime_t now; bzero(xt, sizeof(*xt)); xt->t_state = tp->t_state; xt->t_logstate = tcp_get_bblog_state(tp); xt->t_flags = tp->t_flags; xt->t_sndzerowin = tp->t_sndzerowin; xt->t_sndrexmitpack = tp->t_sndrexmitpack; xt->t_rcvoopack = tp->t_rcvoopack; xt->t_rcv_wnd = tp->rcv_wnd; xt->t_snd_wnd = tp->snd_wnd; xt->t_snd_cwnd = tp->snd_cwnd; xt->t_snd_ssthresh = tp->snd_ssthresh; xt->t_dsack_bytes = tp->t_dsack_bytes; xt->t_dsack_tlp_bytes = tp->t_dsack_tlp_bytes; xt->t_dsack_pack = tp->t_dsack_pack; xt->t_maxseg = tp->t_maxseg; xt->xt_ecn = (tp->t_flags2 & TF2_ECN_PERMIT) ? 1 : 0 + (tp->t_flags2 & TF2_ACE_PERMIT) ? 2 : 0; now = getsbinuptime(); #define COPYTIMER(which,where) do { \ if (tp->t_timers[which] != SBT_MAX) \ xt->where = (tp->t_timers[which] - now) / SBT_1MS; \ else \ xt->where = 0; \ } while (0) COPYTIMER(TT_DELACK, tt_delack); COPYTIMER(TT_REXMT, tt_rexmt); COPYTIMER(TT_PERSIST, tt_persist); COPYTIMER(TT_KEEP, tt_keep); COPYTIMER(TT_2MSL, tt_2msl); #undef COPYTIMER xt->t_rcvtime = 1000 * (ticks - tp->t_rcvtime) / hz; xt->xt_encaps_port = tp->t_port; bcopy(tp->t_fb->tfb_tcp_block_name, xt->xt_stack, TCP_FUNCTION_NAME_LEN_MAX); bcopy(CC_ALGO(tp)->name, xt->xt_cc, TCP_CA_NAME_MAX); #ifdef TCP_BLACKBOX (void)tcp_log_get_id(tp, xt->xt_logid); #endif xt->xt_len = sizeof(struct xtcpcb); in_pcbtoxinpcb(inp, &xt->xt_inp); } void tcp_log_end_status(struct tcpcb *tp, uint8_t status) { uint32_t bit, i; if ((tp == NULL) || (status > TCP_EI_STATUS_MAX_VALUE) || (status == 0)) { /* Invalid */ return; } if (status > (sizeof(uint32_t) * 8)) { /* Should this be a KASSERT? */ return; } bit = 1U << (status - 1); if (bit & tp->t_end_info_status) { /* already logged */ return; } for (i = 0; i < TCP_END_BYTE_INFO; i++) { if (tp->t_end_info_bytes[i] == TCP_EI_EMPTY_SLOT) { tp->t_end_info_bytes[i] = status; tp->t_end_info_status |= bit; break; } } } int tcp_can_enable_pacing(void) { if ((tcp_pacing_limit == -1) || (tcp_pacing_limit > number_of_tcp_connections_pacing)) { atomic_fetchadd_int(&number_of_tcp_connections_pacing, 1); shadow_num_connections = number_of_tcp_connections_pacing; return (1); } else { counter_u64_add(tcp_pacing_failures, 1); return (0); } } int tcp_incr_dgp_pacing_cnt(void) { if ((tcp_dgp_limit == -1) || (tcp_dgp_limit > number_of_dgp_connections)) { atomic_fetchadd_int(&number_of_dgp_connections, 1); shadow_tcp_pacing_dgp = number_of_dgp_connections; return (1); } else { counter_u64_add(tcp_dgp_failures, 1); return (0); } } static uint8_t tcp_dgp_warning = 0; void tcp_dec_dgp_pacing_cnt(void) { uint32_t ret; ret = atomic_fetchadd_int(&number_of_dgp_connections, -1); shadow_tcp_pacing_dgp = number_of_dgp_connections; KASSERT(ret != 0, ("number_of_dgp_connections -1 would cause wrap?")); if (ret == 0) { if (tcp_dgp_limit != -1) { printf("Warning all DGP is now disabled, count decrements invalidly!\n"); tcp_dgp_limit = 0; tcp_dgp_warning = 1; } else if (tcp_dgp_warning == 0) { printf("Warning DGP pacing is invalid, invalid decrement\n"); tcp_dgp_warning = 1; } } } static uint8_t tcp_pacing_warning = 0; void tcp_decrement_paced_conn(void) { uint32_t ret; ret = atomic_fetchadd_int(&number_of_tcp_connections_pacing, -1); shadow_num_connections = number_of_tcp_connections_pacing; KASSERT(ret != 0, ("tcp_paced_connection_exits -1 would cause wrap?")); if (ret == 0) { if (tcp_pacing_limit != -1) { printf("Warning all pacing is now disabled, count decrements invalidly!\n"); tcp_pacing_limit = 0; } else if (tcp_pacing_warning == 0) { printf("Warning pacing count is invalid, invalid decrement\n"); tcp_pacing_warning = 1; } } } static void tcp_default_switch_failed(struct tcpcb *tp) { /* * If a switch fails we only need to * care about two things: * a) The t_flags2 * and * b) The timer granularity. * Timeouts, at least for now, don't use the * old callout system in the other stacks so * those are hopefully safe. */ tcp_lro_features_off(tp); tcp_change_time_units(tp, TCP_TMR_GRANULARITY_TICKS); } #ifdef TCP_ACCOUNTING int tcp_do_ack_accounting(struct tcpcb *tp, struct tcphdr *th, struct tcpopt *to, uint32_t tiwin, int mss) { if (SEQ_LT(th->th_ack, tp->snd_una)) { /* Do we have a SACK? */ if (to->to_flags & TOF_SACK) { if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_cnt_counters[ACK_SACK]++; } return (ACK_SACK); } else { if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_cnt_counters[ACK_BEHIND]++; } return (ACK_BEHIND); } } else if (th->th_ack == tp->snd_una) { /* Do we have a SACK? */ if (to->to_flags & TOF_SACK) { if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_cnt_counters[ACK_SACK]++; } return (ACK_SACK); } else if (tiwin != tp->snd_wnd) { if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_cnt_counters[ACK_RWND]++; } return (ACK_RWND); } else { if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_cnt_counters[ACK_DUPACK]++; } return (ACK_DUPACK); } } else { if (!SEQ_GT(th->th_ack, tp->snd_max)) { if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_cnt_counters[CNT_OF_ACKS_IN] += (((th->th_ack - tp->snd_una) + mss - 1)/mss); } } if (to->to_flags & TOF_SACK) { if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_cnt_counters[ACK_CUMACK_SACK]++; } return (ACK_CUMACK_SACK); } else { if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { tp->tcp_cnt_counters[ACK_CUMACK]++; } return (ACK_CUMACK); } } } #endif void tcp_change_time_units(struct tcpcb *tp, int granularity) { if (tp->t_tmr_granularity == granularity) { /* We are there */ return; } if (granularity == TCP_TMR_GRANULARITY_USEC) { KASSERT((tp->t_tmr_granularity == TCP_TMR_GRANULARITY_TICKS), ("Granularity is not TICKS its %u in tp:%p", tp->t_tmr_granularity, tp)); tp->t_rttlow = TICKS_2_USEC(tp->t_rttlow); if (tp->t_srtt > 1) { uint32_t val, frac; val = tp->t_srtt >> TCP_RTT_SHIFT; frac = tp->t_srtt & 0x1f; tp->t_srtt = TICKS_2_USEC(val); /* * frac is the fractional part of the srtt (if any) * but its in ticks and every bit represents * 1/32nd of a hz. */ if (frac) { if (hz == 1000) { frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_MSEC) / (uint64_t)TCP_RTT_SCALE); } else { frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_SEC) / ((uint64_t)(hz) * (uint64_t)TCP_RTT_SCALE)); } tp->t_srtt += frac; } } if (tp->t_rttvar) { uint32_t val, frac; val = tp->t_rttvar >> TCP_RTTVAR_SHIFT; frac = tp->t_rttvar & 0x1f; tp->t_rttvar = TICKS_2_USEC(val); /* * frac is the fractional part of the srtt (if any) * but its in ticks and every bit represents * 1/32nd of a hz. */ if (frac) { if (hz == 1000) { frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_MSEC) / (uint64_t)TCP_RTT_SCALE); } else { frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_SEC) / ((uint64_t)(hz) * (uint64_t)TCP_RTT_SCALE)); } tp->t_rttvar += frac; } } tp->t_tmr_granularity = TCP_TMR_GRANULARITY_USEC; } else if (granularity == TCP_TMR_GRANULARITY_TICKS) { /* Convert back to ticks, with */ KASSERT((tp->t_tmr_granularity == TCP_TMR_GRANULARITY_USEC), ("Granularity is not USEC its %u in tp:%p", tp->t_tmr_granularity, tp)); if (tp->t_srtt > 1) { uint32_t val, frac; val = USEC_2_TICKS(tp->t_srtt); frac = tp->t_srtt % (HPTS_USEC_IN_SEC / hz); tp->t_srtt = val << TCP_RTT_SHIFT; /* * frac is the fractional part here is left * over from converting to hz and shifting. * We need to convert this to the 5 bit * remainder. */ if (frac) { if (hz == 1000) { frac = (((uint64_t)frac * (uint64_t)TCP_RTT_SCALE) / (uint64_t)HPTS_USEC_IN_MSEC); } else { frac = (((uint64_t)frac * (uint64_t)(hz) * (uint64_t)TCP_RTT_SCALE) /(uint64_t)HPTS_USEC_IN_SEC); } tp->t_srtt += frac; } } if (tp->t_rttvar) { uint32_t val, frac; val = USEC_2_TICKS(tp->t_rttvar); frac = tp->t_rttvar % (HPTS_USEC_IN_SEC / hz); tp->t_rttvar = val << TCP_RTTVAR_SHIFT; /* * frac is the fractional part here is left * over from converting to hz and shifting. * We need to convert this to the 4 bit * remainder. */ if (frac) { if (hz == 1000) { frac = (((uint64_t)frac * (uint64_t)TCP_RTTVAR_SCALE) / (uint64_t)HPTS_USEC_IN_MSEC); } else { frac = (((uint64_t)frac * (uint64_t)(hz) * (uint64_t)TCP_RTTVAR_SCALE) /(uint64_t)HPTS_USEC_IN_SEC); } tp->t_rttvar += frac; } } tp->t_rttlow = USEC_2_TICKS(tp->t_rttlow); tp->t_tmr_granularity = TCP_TMR_GRANULARITY_TICKS; } #ifdef INVARIANTS else { panic("Unknown granularity:%d tp:%p", granularity, tp); } #endif } void tcp_handle_orphaned_packets(struct tcpcb *tp) { struct mbuf *save, *m, *prev; /* * Called when a stack switch is occuring from the fini() * of the old stack. We assue the init() as already been * run of the new stack and it has set the t_flags2 to * what it supports. This function will then deal with any * differences i.e. cleanup packets that maybe queued that * the newstack does not support. */ if (tp->t_flags2 & TF2_MBUF_L_ACKS) return; if ((tp->t_flags2 & TF2_SUPPORTS_MBUFQ) == 0 && !STAILQ_EMPTY(&tp->t_inqueue)) { /* * It is unsafe to process the packets since a * reset may be lurking in them (its rare but it * can occur). If we were to find a RST, then we * would end up dropping the connection and the * INP lock, so when we return the caller (tcp_usrreq) * will blow up when it trys to unlock the inp. * This new stack does not do any fancy LRO features * so all we can do is toss the packets. */ m = STAILQ_FIRST(&tp->t_inqueue); STAILQ_INIT(&tp->t_inqueue); STAILQ_FOREACH_FROM_SAFE(m, &tp->t_inqueue, m_stailqpkt, save) m_freem(m); } else { /* * Here we have a stack that does mbuf queuing but * does not support compressed ack's. We must * walk all the mbufs and discard any compressed acks. */ STAILQ_FOREACH_SAFE(m, &tp->t_inqueue, m_stailqpkt, save) { if (m->m_flags & M_ACKCMP) { if (m == STAILQ_FIRST(&tp->t_inqueue)) STAILQ_REMOVE_HEAD(&tp->t_inqueue, m_stailqpkt); else STAILQ_REMOVE_AFTER(&tp->t_inqueue, prev, m_stailqpkt); m_freem(m); } else prev = m; } } } #ifdef TCP_REQUEST_TRK uint32_t tcp_estimate_tls_overhead(struct socket *so, uint64_t tls_usr_bytes) { #ifdef KERN_TLS struct ktls_session *tls; uint32_t rec_oh, records; tls = so->so_snd.sb_tls_info; if (tls == NULL) return (0); rec_oh = tls->params.tls_hlen + tls->params.tls_tlen; records = ((tls_usr_bytes + tls->params.max_frame_len - 1)/tls->params.max_frame_len); return (records * rec_oh); #else return (0); #endif } extern uint32_t tcp_stale_entry_time; uint32_t tcp_stale_entry_time = 250000; SYSCTL_UINT(_net_inet_tcp, OID_AUTO, usrlog_stale, CTLFLAG_RW, &tcp_stale_entry_time, 250000, "Time that a tcpreq entry without a sendfile ages out"); void tcp_req_log_req_info(struct tcpcb *tp, struct tcp_sendfile_track *req, uint16_t slot, uint8_t val, uint64_t offset, uint64_t nbytes) { if (tcp_bblogging_on(tp)) { union tcp_log_stackspecific log; struct timeval tv; memset(&log.u_bbr, 0, sizeof(log.u_bbr)); log.u_bbr.inhpts = tcp_in_hpts(tp); log.u_bbr.flex8 = val; log.u_bbr.rttProp = req->timestamp; log.u_bbr.delRate = req->start; log.u_bbr.cur_del_rate = req->end; log.u_bbr.flex1 = req->start_seq; log.u_bbr.flex2 = req->end_seq; log.u_bbr.flex3 = req->flags; log.u_bbr.flex4 = ((req->localtime >> 32) & 0x00000000ffffffff); log.u_bbr.flex5 = (req->localtime & 0x00000000ffffffff); log.u_bbr.flex7 = slot; log.u_bbr.bw_inuse = offset; /* nbytes = flex6 | epoch */ log.u_bbr.flex6 = ((nbytes >> 32) & 0x00000000ffffffff); log.u_bbr.epoch = (nbytes & 0x00000000ffffffff); /* cspr = lt_epoch | pkts_out */ log.u_bbr.lt_epoch = ((req->cspr >> 32) & 0x00000000ffffffff); log.u_bbr.pkts_out |= (req->cspr & 0x00000000ffffffff); log.u_bbr.applimited = tp->t_tcpreq_closed; log.u_bbr.applimited <<= 8; log.u_bbr.applimited |= tp->t_tcpreq_open; log.u_bbr.applimited <<= 8; log.u_bbr.applimited |= tp->t_tcpreq_req; log.u_bbr.timeStamp = tcp_get_usecs(&tv); TCP_LOG_EVENTP(tp, NULL, &tptosocket(tp)->so_rcv, &tptosocket(tp)->so_snd, TCP_LOG_REQ_T, 0, 0, &log, false, &tv); } } void tcp_req_free_a_slot(struct tcpcb *tp, struct tcp_sendfile_track *ent) { if (tp->t_tcpreq_req > 0) tp->t_tcpreq_req--; if (ent->flags & TCP_TRK_TRACK_FLG_OPEN) { if (tp->t_tcpreq_open > 0) tp->t_tcpreq_open--; } else { if (tp->t_tcpreq_closed > 0) tp->t_tcpreq_closed--; } ent->flags = TCP_TRK_TRACK_FLG_EMPTY; } static void tcp_req_check_for_stale_entries(struct tcpcb *tp, uint64_t ts, int rm_oldest) { struct tcp_sendfile_track *ent; uint64_t time_delta, oldest_delta; int i, oldest, oldest_set = 0, cnt_rm = 0; for (i = 0; i < MAX_TCP_TRK_REQ; i++) { ent = &tp->t_tcpreq_info[i]; if (ent->flags != TCP_TRK_TRACK_FLG_USED) { /* * We only care about closed end ranges * that are allocated and have no sendfile * ever touching them. They would be in * state USED. */ continue; } if (ts >= ent->localtime) time_delta = ts - ent->localtime; else time_delta = 0; if (time_delta && ((oldest_delta < time_delta) || (oldest_set == 0))) { oldest_set = 1; oldest = i; oldest_delta = time_delta; } if (tcp_stale_entry_time && (time_delta >= tcp_stale_entry_time)) { /* * No sendfile in a our time-limit * time to purge it. */ cnt_rm++; tcp_req_log_req_info(tp, &tp->t_tcpreq_info[i], i, TCP_TRK_REQ_LOG_STALE, time_delta, 0); tcp_req_free_a_slot(tp, ent); } } if ((cnt_rm == 0) && rm_oldest && oldest_set) { ent = &tp->t_tcpreq_info[oldest]; tcp_req_log_req_info(tp, &tp->t_tcpreq_info[i], i, TCP_TRK_REQ_LOG_STALE, oldest_delta, 1); tcp_req_free_a_slot(tp, ent); } } int tcp_req_check_for_comp(struct tcpcb *tp, tcp_seq ack_point) { int i, ret = 0; struct tcp_sendfile_track *ent; /* Clean up any old closed end requests that are now completed */ if (tp->t_tcpreq_req == 0) return (0); if (tp->t_tcpreq_closed == 0) return (0); for (i = 0; i < MAX_TCP_TRK_REQ; i++) { ent = &tp->t_tcpreq_info[i]; /* Skip empty ones */ if (ent->flags == TCP_TRK_TRACK_FLG_EMPTY) continue; /* Skip open ones */ if (ent->flags & TCP_TRK_TRACK_FLG_OPEN) continue; if (SEQ_GEQ(ack_point, ent->end_seq)) { /* We are past it -- free it */ tcp_req_log_req_info(tp, ent, i, TCP_TRK_REQ_LOG_FREED, 0, 0); tcp_req_free_a_slot(tp, ent); ret++; } } return (ret); } int tcp_req_is_entry_comp(struct tcpcb *tp, struct tcp_sendfile_track *ent, tcp_seq ack_point) { if (tp->t_tcpreq_req == 0) return (-1); if (tp->t_tcpreq_closed == 0) return (-1); if (ent->flags == TCP_TRK_TRACK_FLG_EMPTY) return (-1); if (SEQ_GEQ(ack_point, ent->end_seq)) { return (1); } return (0); } struct tcp_sendfile_track * tcp_req_find_a_req_that_is_completed_by(struct tcpcb *tp, tcp_seq th_ack, int *ip) { /* * Given an ack point (th_ack) walk through our entries and * return the first one found that th_ack goes past the * end_seq. */ struct tcp_sendfile_track *ent; int i; if (tp->t_tcpreq_req == 0) { /* none open */ return (NULL); } for (i = 0; i < MAX_TCP_TRK_REQ; i++) { ent = &tp->t_tcpreq_info[i]; if (ent->flags == TCP_TRK_TRACK_FLG_EMPTY) continue; if ((ent->flags & TCP_TRK_TRACK_FLG_OPEN) == 0) { if (SEQ_GEQ(th_ack, ent->end_seq)) { *ip = i; return (ent); } } } return (NULL); } struct tcp_sendfile_track * tcp_req_find_req_for_seq(struct tcpcb *tp, tcp_seq seq) { struct tcp_sendfile_track *ent; int i; if (tp->t_tcpreq_req == 0) { /* none open */ return (NULL); } for (i = 0; i < MAX_TCP_TRK_REQ; i++) { ent = &tp->t_tcpreq_info[i]; tcp_req_log_req_info(tp, ent, i, TCP_TRK_REQ_LOG_SEARCH, (uint64_t)seq, 0); if (ent->flags == TCP_TRK_TRACK_FLG_EMPTY) { continue; } if (ent->flags & TCP_TRK_TRACK_FLG_OPEN) { /* * An open end request only needs to * match the beginning seq or be * all we have (once we keep going on * a open end request we may have a seq * wrap). */ if ((SEQ_GEQ(seq, ent->start_seq)) || (tp->t_tcpreq_closed == 0)) return (ent); } else { /* * For this one we need to * be a bit more careful if its * completed at least. */ if ((SEQ_GEQ(seq, ent->start_seq)) && (SEQ_LT(seq, ent->end_seq))) { return (ent); } } } return (NULL); } /* Should this be in its own file tcp_req.c ? */ struct tcp_sendfile_track * tcp_req_alloc_req_full(struct tcpcb *tp, struct tcp_snd_req *req, uint64_t ts, int rec_dups) { struct tcp_sendfile_track *fil; int i, allocated; /* In case the stack does not check for completions do so now */ tcp_req_check_for_comp(tp, tp->snd_una); /* Check for stale entries */ if (tp->t_tcpreq_req) tcp_req_check_for_stale_entries(tp, ts, (tp->t_tcpreq_req >= MAX_TCP_TRK_REQ)); /* Check to see if this is a duplicate of one not started */ if (tp->t_tcpreq_req) { for (i = 0, allocated = 0; i < MAX_TCP_TRK_REQ; i++) { fil = &tp->t_tcpreq_info[i]; if ((fil->flags & TCP_TRK_TRACK_FLG_USED) == 0) continue; if ((fil->timestamp == req->timestamp) && (fil->start == req->start) && ((fil->flags & TCP_TRK_TRACK_FLG_OPEN) || (fil->end == req->end))) { /* * We already have this request * and it has not been started with sendfile. * This probably means the user was returned * a 4xx of some sort and its going to age * out, lets not duplicate it. */ return (fil); } } } /* Ok if there is no room at the inn we are in trouble */ if (tp->t_tcpreq_req >= MAX_TCP_TRK_REQ) { tcp_trace_point(tp, TCP_TP_REQ_LOG_FAIL); for (i = 0; i < MAX_TCP_TRK_REQ; i++) { tcp_req_log_req_info(tp, &tp->t_tcpreq_info[i], i, TCP_TRK_REQ_LOG_ALLOCFAIL, 0, 0); } return (NULL); } for (i = 0, allocated = 0; i < MAX_TCP_TRK_REQ; i++) { fil = &tp->t_tcpreq_info[i]; if (fil->flags == TCP_TRK_TRACK_FLG_EMPTY) { allocated = 1; fil->flags = TCP_TRK_TRACK_FLG_USED; fil->timestamp = req->timestamp; fil->playout_ms = req->playout_ms; fil->localtime = ts; fil->start = req->start; if (req->flags & TCP_LOG_HTTPD_RANGE_END) { fil->end = req->end; } else { fil->end = 0; fil->flags |= TCP_TRK_TRACK_FLG_OPEN; } /* * We can set the min boundaries to the TCP Sequence space, * but it might be found to be further up when sendfile * actually runs on this range (if it ever does). */ fil->sbcc_at_s = tptosocket(tp)->so_snd.sb_ccc; fil->start_seq = tp->snd_una + tptosocket(tp)->so_snd.sb_ccc; if (req->flags & TCP_LOG_HTTPD_RANGE_END) fil->end_seq = (fil->start_seq + ((uint32_t)(fil->end - fil->start))); else fil->end_seq = 0; if (tptosocket(tp)->so_snd.sb_tls_info) { /* * This session is doing TLS. Take a swag guess * at the overhead. */ fil->end_seq += tcp_estimate_tls_overhead( tptosocket(tp), (fil->end - fil->start)); } tp->t_tcpreq_req++; if (fil->flags & TCP_TRK_TRACK_FLG_OPEN) tp->t_tcpreq_open++; else tp->t_tcpreq_closed++; tcp_req_log_req_info(tp, fil, i, TCP_TRK_REQ_LOG_NEW, 0, 0); break; } else fil = NULL; } return (fil); } void tcp_req_alloc_req(struct tcpcb *tp, union tcp_log_userdata *user, uint64_t ts) { (void)tcp_req_alloc_req_full(tp, &user->tcp_req, ts, 1); } #endif void tcp_log_socket_option(struct tcpcb *tp, uint32_t option_num, uint32_t option_val, int err) { if (tcp_bblogging_on(tp)) { struct tcp_log_buffer *l; l = tcp_log_event(tp, NULL, &tptosocket(tp)->so_rcv, &tptosocket(tp)->so_snd, TCP_LOG_SOCKET_OPT, err, 0, NULL, 1, NULL, NULL, 0, NULL); if (l) { l->tlb_flex1 = option_num; l->tlb_flex2 = option_val; } } } uint32_t tcp_get_srtt(struct tcpcb *tp, int granularity) { uint32_t srtt; KASSERT(granularity == TCP_TMR_GRANULARITY_USEC || granularity == TCP_TMR_GRANULARITY_TICKS, ("%s: called with unexpected granularity %d", __func__, granularity)); srtt = tp->t_srtt; /* * We only support two granularities. If the stored granularity * does not match the granularity requested by the caller, * convert the stored value to the requested unit of granularity. */ if (tp->t_tmr_granularity != granularity) { if (granularity == TCP_TMR_GRANULARITY_USEC) srtt = TICKS_2_USEC(srtt); else srtt = USEC_2_TICKS(srtt); } /* * If the srtt is stored with ticks granularity, we need to * unshift to get the actual value. We do this after the * conversion above (if one was necessary) in order to maximize * precision. */ if (tp->t_tmr_granularity == TCP_TMR_GRANULARITY_TICKS) srtt = srtt >> TCP_RTT_SHIFT; return (srtt); } void tcp_account_for_send(struct tcpcb *tp, uint32_t len, uint8_t is_rxt, uint8_t is_tlp, bool hw_tls) { if (is_tlp) { tp->t_sndtlppack++; tp->t_sndtlpbyte += len; } /* To get total bytes sent you must add t_snd_rxt_bytes to t_sndbytes */ if (is_rxt) tp->t_snd_rxt_bytes += len; else tp->t_sndbytes += len; #ifdef KERN_TLS if (hw_tls && is_rxt && len != 0) { uint64_t rexmit_percent; rexmit_percent = (1000ULL * tp->t_snd_rxt_bytes) / (10ULL * (tp->t_snd_rxt_bytes + tp->t_sndbytes)); if (rexmit_percent > ktls_ifnet_max_rexmit_pct) ktls_disable_ifnet(tp); } #endif } diff --git a/sys/netinet/tcp_usrreq.c b/sys/netinet/tcp_usrreq.c index 8326c67cf085..9a6e80363f0c 100644 --- a/sys/netinet/tcp_usrreq.c +++ b/sys/netinet/tcp_usrreq.c @@ -1,3194 +1,3194 @@ /*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 1982, 1986, 1988, 1993 * The Regents of the University of California. * Copyright (c) 2006-2007 Robert N. M. Watson * Copyright (c) 2010-2011 Juniper Networks, Inc. * All rights reserved. * * Portions of this software were developed by Robert N. M. Watson under * contract to Juniper Networks, Inc. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include #include "opt_ddb.h" #include "opt_inet.h" #include "opt_inet6.h" #include "opt_ipsec.h" #include "opt_kern_tls.h" #include #include #include #include #include #include #include #include #include #include #include #ifdef INET6 #include #endif /* INET6 */ #include #include #include #include #include #include #ifdef DDB #include #endif #include #include #include #include #include #include #include #include #include #include #include #ifdef INET6 #include #include #include #include #endif #include #include #include #include #include #include #include #include #include #include #ifdef TCPPCAP #include #endif #ifdef TCP_OFFLOAD #include #endif #include #include #include #include #include #include #include /* * TCP protocol interface to socket abstraction. */ #ifdef INET static int tcp_connect(struct tcpcb *, struct sockaddr_in *, struct thread *td); #endif /* INET */ #ifdef INET6 static int tcp6_connect(struct tcpcb *, struct sockaddr_in6 *, struct thread *td); #endif /* INET6 */ static void tcp_disconnect(struct tcpcb *); static void tcp_usrclosed(struct tcpcb *); static void tcp_fill_info(const struct tcpcb *, struct tcp_info *); static int tcp_pru_options_support(struct tcpcb *tp, int flags); static void tcp_bblog_pru(struct tcpcb *tp, uint32_t pru, int error) { struct tcp_log_buffer *lgb; KASSERT(tp != NULL, ("tcp_bblog_pru: tp == NULL")); INP_WLOCK_ASSERT(tptoinpcb(tp)); if (tcp_bblogging_on(tp)) { lgb = tcp_log_event(tp, NULL, NULL, NULL, TCP_LOG_PRU, error, 0, NULL, false, NULL, NULL, 0, NULL); } else { lgb = NULL; } if (lgb != NULL) { if (error >= 0) { lgb->tlb_errno = (uint32_t)error; } lgb->tlb_flex1 = pru; } } /* * TCP attaches to socket via pru_attach(), reserving space, * and an internet control block. */ static int tcp_usr_attach(struct socket *so, int proto, struct thread *td) { struct inpcb *inp; struct tcpcb *tp = NULL; int error; inp = sotoinpcb(so); KASSERT(inp == NULL, ("tcp_usr_attach: inp != NULL")); error = soreserve(so, V_tcp_sendspace, V_tcp_recvspace); if (error) goto out; so->so_rcv.sb_flags |= SB_AUTOSIZE; so->so_snd.sb_flags |= SB_AUTOSIZE; error = in_pcballoc(so, &V_tcbinfo); if (error) goto out; inp = sotoinpcb(so); tp = tcp_newtcpcb(inp, NULL); if (tp == NULL) { error = ENOBUFS; in_pcbfree(inp); goto out; } tp->t_state = TCPS_CLOSED; tcp_bblog_pru(tp, PRU_ATTACH, error); INP_WUNLOCK(inp); TCPSTATES_INC(TCPS_CLOSED); out: TCP_PROBE2(debug__user, tp, PRU_ATTACH); return (error); } /* * tcp_usr_detach is called when the socket layer loses its final reference * to the socket, be it a file descriptor reference, a reference from TCP, * etc. At this point, there is only one case in which we will keep around * inpcb state: time wait. */ static void tcp_usr_detach(struct socket *so) { struct inpcb *inp; struct tcpcb *tp; inp = sotoinpcb(so); KASSERT(inp != NULL, ("%s: inp == NULL", __func__)); INP_WLOCK(inp); KASSERT(so->so_pcb == inp && inp->inp_socket == so, ("%s: socket %p inp %p mismatch", __func__, so, inp)); tp = intotcpcb(inp); KASSERT(inp->inp_flags & INP_DROPPED || tp->t_state < TCPS_SYN_SENT, ("%s: inp %p not dropped or embryonic", __func__, inp)); tcp_discardcb(tp); in_pcbfree(inp); } #ifdef INET /* * Give the socket an address. */ static int tcp_usr_bind(struct socket *so, struct sockaddr *nam, struct thread *td) { int error = 0; struct inpcb *inp; struct tcpcb *tp; struct sockaddr_in *sinp; inp = sotoinpcb(so); KASSERT(inp != NULL, ("tcp_usr_bind: inp == NULL")); INP_WLOCK(inp); if (inp->inp_flags & INP_DROPPED) { INP_WUNLOCK(inp); return (EINVAL); } tp = intotcpcb(inp); sinp = (struct sockaddr_in *)nam; if (nam->sa_family != AF_INET) { /* * Preserve compatibility with old programs. */ if (nam->sa_family != AF_UNSPEC || nam->sa_len < offsetof(struct sockaddr_in, sin_zero) || sinp->sin_addr.s_addr != INADDR_ANY) { error = EAFNOSUPPORT; goto out; } nam->sa_family = AF_INET; } if (nam->sa_len != sizeof(*sinp)) { error = EINVAL; goto out; } /* * Must check for multicast addresses and disallow binding * to them. */ if (IN_MULTICAST(ntohl(sinp->sin_addr.s_addr))) { error = EAFNOSUPPORT; goto out; } INP_HASH_WLOCK(&V_tcbinfo); error = in_pcbbind(inp, sinp, td->td_ucred); INP_HASH_WUNLOCK(&V_tcbinfo); out: tcp_bblog_pru(tp, PRU_BIND, error); TCP_PROBE2(debug__user, tp, PRU_BIND); INP_WUNLOCK(inp); return (error); } #endif /* INET */ #ifdef INET6 static int tcp6_usr_bind(struct socket *so, struct sockaddr *nam, struct thread *td) { int error = 0; struct inpcb *inp; struct tcpcb *tp; struct sockaddr_in6 *sin6; u_char vflagsav; inp = sotoinpcb(so); KASSERT(inp != NULL, ("tcp6_usr_bind: inp == NULL")); INP_WLOCK(inp); if (inp->inp_flags & INP_DROPPED) { INP_WUNLOCK(inp); return (EINVAL); } tp = intotcpcb(inp); vflagsav = inp->inp_vflag; sin6 = (struct sockaddr_in6 *)nam; if (nam->sa_family != AF_INET6) { error = EAFNOSUPPORT; goto out; } if (nam->sa_len != sizeof(*sin6)) { error = EINVAL; goto out; } /* * Must check for multicast addresses and disallow binding * to them. */ if (IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) { error = EAFNOSUPPORT; goto out; } INP_HASH_WLOCK(&V_tcbinfo); inp->inp_vflag &= ~INP_IPV4; inp->inp_vflag |= INP_IPV6; #ifdef INET if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) { if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) inp->inp_vflag |= INP_IPV4; else if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) { struct sockaddr_in sin; in6_sin6_2_sin(&sin, sin6); if (IN_MULTICAST(ntohl(sin.sin_addr.s_addr))) { error = EAFNOSUPPORT; INP_HASH_WUNLOCK(&V_tcbinfo); goto out; } inp->inp_vflag |= INP_IPV4; inp->inp_vflag &= ~INP_IPV6; error = in_pcbbind(inp, &sin, td->td_ucred); INP_HASH_WUNLOCK(&V_tcbinfo); goto out; } } #endif error = in6_pcbbind(inp, sin6, td->td_ucred); INP_HASH_WUNLOCK(&V_tcbinfo); out: if (error != 0) inp->inp_vflag = vflagsav; tcp_bblog_pru(tp, PRU_BIND, error); TCP_PROBE2(debug__user, tp, PRU_BIND); INP_WUNLOCK(inp); return (error); } #endif /* INET6 */ #ifdef INET /* * Prepare to accept connections. */ static int tcp_usr_listen(struct socket *so, int backlog, struct thread *td) { int error = 0; struct inpcb *inp; struct tcpcb *tp; inp = sotoinpcb(so); KASSERT(inp != NULL, ("tcp_usr_listen: inp == NULL")); INP_WLOCK(inp); if (inp->inp_flags & INP_DROPPED) { INP_WUNLOCK(inp); return (EINVAL); } tp = intotcpcb(inp); SOCK_LOCK(so); error = solisten_proto_check(so); if (error != 0) { SOCK_UNLOCK(so); goto out; } if (inp->inp_lport == 0) { INP_HASH_WLOCK(&V_tcbinfo); error = in_pcbbind(inp, NULL, td->td_ucred); INP_HASH_WUNLOCK(&V_tcbinfo); } if (error == 0) { tcp_state_change(tp, TCPS_LISTEN); solisten_proto(so, backlog); #ifdef TCP_OFFLOAD if ((so->so_options & SO_NO_OFFLOAD) == 0) tcp_offload_listen_start(tp); #endif } else { solisten_proto_abort(so); } SOCK_UNLOCK(so); if (tp->t_flags & TF_FASTOPEN) tp->t_tfo_pending = tcp_fastopen_alloc_counter(); out: tcp_bblog_pru(tp, PRU_LISTEN, error); TCP_PROBE2(debug__user, tp, PRU_LISTEN); INP_WUNLOCK(inp); return (error); } #endif /* INET */ #ifdef INET6 static int tcp6_usr_listen(struct socket *so, int backlog, struct thread *td) { int error = 0; struct inpcb *inp; struct tcpcb *tp; u_char vflagsav; inp = sotoinpcb(so); KASSERT(inp != NULL, ("tcp6_usr_listen: inp == NULL")); INP_WLOCK(inp); if (inp->inp_flags & INP_DROPPED) { INP_WUNLOCK(inp); return (EINVAL); } tp = intotcpcb(inp); vflagsav = inp->inp_vflag; SOCK_LOCK(so); error = solisten_proto_check(so); if (error != 0) { SOCK_UNLOCK(so); goto out; } INP_HASH_WLOCK(&V_tcbinfo); if (inp->inp_lport == 0) { inp->inp_vflag &= ~INP_IPV4; if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) inp->inp_vflag |= INP_IPV4; error = in6_pcbbind(inp, NULL, td->td_ucred); } INP_HASH_WUNLOCK(&V_tcbinfo); if (error == 0) { tcp_state_change(tp, TCPS_LISTEN); solisten_proto(so, backlog); #ifdef TCP_OFFLOAD if ((so->so_options & SO_NO_OFFLOAD) == 0) tcp_offload_listen_start(tp); #endif } else { solisten_proto_abort(so); } SOCK_UNLOCK(so); if (tp->t_flags & TF_FASTOPEN) tp->t_tfo_pending = tcp_fastopen_alloc_counter(); if (error != 0) inp->inp_vflag = vflagsav; out: tcp_bblog_pru(tp, PRU_LISTEN, error); TCP_PROBE2(debug__user, tp, PRU_LISTEN); INP_WUNLOCK(inp); return (error); } #endif /* INET6 */ #ifdef INET /* * Initiate connection to peer. * Create a template for use in transmissions on this connection. * Enter SYN_SENT state, and mark socket as connecting. * Start keep-alive timer, and seed output sequence space. * Send initial segment on connection. */ static int tcp_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td) { struct epoch_tracker et; int error = 0; struct inpcb *inp; struct tcpcb *tp; struct sockaddr_in *sinp; inp = sotoinpcb(so); KASSERT(inp != NULL, ("tcp_usr_connect: inp == NULL")); INP_WLOCK(inp); if (inp->inp_flags & INP_DROPPED) { INP_WUNLOCK(inp); return (ECONNREFUSED); } tp = intotcpcb(inp); sinp = (struct sockaddr_in *)nam; if (nam->sa_family != AF_INET) { error = EAFNOSUPPORT; goto out; } if (nam->sa_len != sizeof (*sinp)) { error = EINVAL; goto out; } /* * Must disallow TCP ``connections'' to multicast addresses. */ if (IN_MULTICAST(ntohl(sinp->sin_addr.s_addr))) { error = EAFNOSUPPORT; goto out; } if (ntohl(sinp->sin_addr.s_addr) == INADDR_BROADCAST) { error = EACCES; goto out; } if ((error = prison_remote_ip4(td->td_ucred, &sinp->sin_addr)) != 0) goto out; if (SOLISTENING(so)) { error = EOPNOTSUPP; goto out; } NET_EPOCH_ENTER(et); if ((error = tcp_connect(tp, sinp, td)) != 0) goto out_in_epoch; #ifdef TCP_OFFLOAD if (registered_toedevs > 0 && (so->so_options & SO_NO_OFFLOAD) == 0 && (error = tcp_offload_connect(so, nam)) == 0) goto out_in_epoch; #endif tcp_timer_activate(tp, TT_KEEP, TP_KEEPINIT(tp)); error = tcp_output(tp); KASSERT(error >= 0, ("TCP stack %s requested tcp_drop(%p) at connect()" ", error code %d", tp->t_fb->tfb_tcp_block_name, tp, -error)); out_in_epoch: NET_EPOCH_EXIT(et); out: tcp_bblog_pru(tp, PRU_CONNECT, error); TCP_PROBE2(debug__user, tp, PRU_CONNECT); INP_WUNLOCK(inp); return (error); } #endif /* INET */ #ifdef INET6 static int tcp6_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td) { struct epoch_tracker et; int error = 0; struct inpcb *inp; struct tcpcb *tp; struct sockaddr_in6 *sin6; u_int8_t incflagsav; u_char vflagsav; inp = sotoinpcb(so); KASSERT(inp != NULL, ("tcp6_usr_connect: inp == NULL")); INP_WLOCK(inp); if (inp->inp_flags & INP_DROPPED) { INP_WUNLOCK(inp); return (ECONNREFUSED); } tp = intotcpcb(inp); vflagsav = inp->inp_vflag; incflagsav = inp->inp_inc.inc_flags; sin6 = (struct sockaddr_in6 *)nam; if (nam->sa_family != AF_INET6) { error = EAFNOSUPPORT; goto out; } if (nam->sa_len != sizeof (*sin6)) { error = EINVAL; goto out; } /* * Must disallow TCP ``connections'' to multicast addresses. */ if (IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) { error = EAFNOSUPPORT; goto out; } if (SOLISTENING(so)) { error = EINVAL; goto out; } #ifdef INET /* * XXXRW: Some confusion: V4/V6 flags relate to binding, and * therefore probably require the hash lock, which isn't held here. * Is this a significant problem? */ if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) { struct sockaddr_in sin; if ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0) { error = EINVAL; goto out; } if ((inp->inp_vflag & INP_IPV4) == 0) { error = EAFNOSUPPORT; goto out; } in6_sin6_2_sin(&sin, sin6); if (IN_MULTICAST(ntohl(sin.sin_addr.s_addr))) { error = EAFNOSUPPORT; goto out; } if (ntohl(sin.sin_addr.s_addr) == INADDR_BROADCAST) { error = EACCES; goto out; } if ((error = prison_remote_ip4(td->td_ucred, &sin.sin_addr)) != 0) goto out; inp->inp_vflag |= INP_IPV4; inp->inp_vflag &= ~INP_IPV6; NET_EPOCH_ENTER(et); if ((error = tcp_connect(tp, &sin, td)) != 0) goto out_in_epoch; #ifdef TCP_OFFLOAD if (registered_toedevs > 0 && (so->so_options & SO_NO_OFFLOAD) == 0 && (error = tcp_offload_connect(so, nam)) == 0) goto out_in_epoch; #endif error = tcp_output(tp); goto out_in_epoch; } else { if ((inp->inp_vflag & INP_IPV6) == 0) { error = EAFNOSUPPORT; goto out; } } #endif if ((error = prison_remote_ip6(td->td_ucred, &sin6->sin6_addr)) != 0) goto out; inp->inp_vflag &= ~INP_IPV4; inp->inp_vflag |= INP_IPV6; inp->inp_inc.inc_flags |= INC_ISIPV6; NET_EPOCH_ENTER(et); if ((error = tcp6_connect(tp, sin6, td)) != 0) goto out_in_epoch; #ifdef TCP_OFFLOAD if (registered_toedevs > 0 && (so->so_options & SO_NO_OFFLOAD) == 0 && (error = tcp_offload_connect(so, nam)) == 0) goto out_in_epoch; #endif tcp_timer_activate(tp, TT_KEEP, TP_KEEPINIT(tp)); error = tcp_output(tp); out_in_epoch: NET_EPOCH_EXIT(et); out: KASSERT(error >= 0, ("TCP stack %s requested tcp_drop(%p) at connect()" ", error code %d", tp->t_fb->tfb_tcp_block_name, tp, -error)); /* * If the implicit bind in the connect call fails, restore * the flags we modified. */ if (error != 0 && inp->inp_lport == 0) { inp->inp_vflag = vflagsav; inp->inp_inc.inc_flags = incflagsav; } tcp_bblog_pru(tp, PRU_CONNECT, error); TCP_PROBE2(debug__user, tp, PRU_CONNECT); INP_WUNLOCK(inp); return (error); } #endif /* INET6 */ /* * Initiate disconnect from peer. * If connection never passed embryonic stage, just drop; * else if don't need to let data drain, then can just drop anyways, * else have to begin TCP shutdown process: mark socket disconnecting, * drain unread data, state switch to reflect user close, and * send segment (e.g. FIN) to peer. Socket will be really disconnected * when peer sends FIN and acks ours. * * SHOULD IMPLEMENT LATER PRU_CONNECT VIA REALLOC TCPCB. */ static int tcp_usr_disconnect(struct socket *so) { struct inpcb *inp; struct tcpcb *tp = NULL; struct epoch_tracker et; int error = 0; NET_EPOCH_ENTER(et); inp = sotoinpcb(so); KASSERT(inp != NULL, ("tcp_usr_disconnect: inp == NULL")); INP_WLOCK(inp); if (inp->inp_flags & INP_DROPPED) { INP_WUNLOCK(inp); NET_EPOCH_EXIT(et); return (ECONNRESET); } tp = intotcpcb(inp); if (tp->t_state == TCPS_TIME_WAIT) goto out; tcp_disconnect(tp); out: tcp_bblog_pru(tp, PRU_DISCONNECT, error); TCP_PROBE2(debug__user, tp, PRU_DISCONNECT); INP_WUNLOCK(inp); NET_EPOCH_EXIT(et); return (error); } #ifdef INET /* * Accept a connection. Essentially all the work is done at higher levels; * just return the address of the peer, storing through addr. */ static int tcp_usr_accept(struct socket *so, struct sockaddr *sa) { struct inpcb *inp; struct tcpcb *tp; int error = 0; inp = sotoinpcb(so); KASSERT(inp != NULL, ("tcp_usr_accept: inp == NULL")); INP_WLOCK(inp); if (inp->inp_flags & INP_DROPPED) { INP_WUNLOCK(inp); return (ECONNABORTED); } tp = intotcpcb(inp); if (so->so_state & SS_ISDISCONNECTED) error = ECONNABORTED; else *(struct sockaddr_in *)sa = (struct sockaddr_in ){ .sin_family = AF_INET, .sin_len = sizeof(struct sockaddr_in), .sin_port = inp->inp_fport, .sin_addr = inp->inp_faddr, }; tcp_bblog_pru(tp, PRU_ACCEPT, error); TCP_PROBE2(debug__user, tp, PRU_ACCEPT); INP_WUNLOCK(inp); return (error); } #endif /* INET */ #ifdef INET6 static int tcp6_usr_accept(struct socket *so, struct sockaddr *sa) { struct inpcb *inp; struct tcpcb *tp; int error = 0; inp = sotoinpcb(so); KASSERT(inp != NULL, ("tcp6_usr_accept: inp == NULL")); INP_WLOCK(inp); if (inp->inp_flags & INP_DROPPED) { INP_WUNLOCK(inp); return (ECONNABORTED); } tp = intotcpcb(inp); if (so->so_state & SS_ISDISCONNECTED) { error = ECONNABORTED; } else { if (inp->inp_vflag & INP_IPV4) { struct sockaddr_in sin = { .sin_family = AF_INET, .sin_len = sizeof(struct sockaddr_in), .sin_port = inp->inp_fport, .sin_addr = inp->inp_faddr, }; in6_sin_2_v4mapsin6(&sin, (struct sockaddr_in6 *)sa); } else { *(struct sockaddr_in6 *)sa = (struct sockaddr_in6 ){ .sin6_family = AF_INET6, .sin6_len = sizeof(struct sockaddr_in6), .sin6_port = inp->inp_fport, .sin6_addr = inp->in6p_faddr, }; /* XXX: should catch errors */ (void)sa6_recoverscope((struct sockaddr_in6 *)sa); } } tcp_bblog_pru(tp, PRU_ACCEPT, error); TCP_PROBE2(debug__user, tp, PRU_ACCEPT); INP_WUNLOCK(inp); return (error); } #endif /* INET6 */ /* * Mark the connection as being incapable of further output. */ static int tcp_usr_shutdown(struct socket *so, enum shutdown_how how) { struct epoch_tracker et; struct inpcb *inp = sotoinpcb(so); struct tcpcb *tp = intotcpcb(inp); int error = 0; SOCK_LOCK(so); if (SOLISTENING(so)) { if (how != SHUT_WR) { so->so_error = ECONNABORTED; solisten_wakeup(so); /* unlocks so */ } else SOCK_UNLOCK(so); return (ENOTCONN); } else if ((so->so_state & (SS_ISCONNECTED | SS_ISCONNECTING | SS_ISDISCONNECTING)) == 0) { SOCK_UNLOCK(so); return (ENOTCONN); } SOCK_UNLOCK(so); switch (how) { case SHUT_RD: sorflush(so); break; case SHUT_RDWR: sorflush(so); /* FALLTHROUGH */ case SHUT_WR: /* * XXXGL: mimicing old soshutdown() here. But shouldn't we * return ECONNRESEST for SHUT_RD as well? */ INP_WLOCK(inp); if (inp->inp_flags & INP_DROPPED) { INP_WUNLOCK(inp); return (ECONNRESET); } socantsendmore(so); NET_EPOCH_ENTER(et); tcp_usrclosed(tp); error = tcp_output_nodrop(tp); tcp_bblog_pru(tp, PRU_SHUTDOWN, error); TCP_PROBE2(debug__user, tp, PRU_SHUTDOWN); error = tcp_unlock_or_drop(tp, error); NET_EPOCH_EXIT(et); } wakeup(&so->so_timeo); return (error); } /* * After a receive, possibly send window update to peer. */ static int tcp_usr_rcvd(struct socket *so, int flags) { struct epoch_tracker et; struct inpcb *inp; struct tcpcb *tp; int outrv = 0, error = 0; inp = sotoinpcb(so); KASSERT(inp != NULL, ("tcp_usr_rcvd: inp == NULL")); INP_WLOCK(inp); if (inp->inp_flags & INP_DROPPED) { INP_WUNLOCK(inp); return (ECONNRESET); } tp = intotcpcb(inp); NET_EPOCH_ENTER(et); /* * For passively-created TFO connections, don't attempt a window * update while still in SYN_RECEIVED as this may trigger an early * SYN|ACK. It is preferable to have the SYN|ACK be sent along with * application response data, or failing that, when the DELACK timer * expires. */ if ((tp->t_flags & TF_FASTOPEN) && (tp->t_state == TCPS_SYN_RECEIVED)) goto out; #ifdef TCP_OFFLOAD if (tp->t_flags & TF_TOE) tcp_offload_rcvd(tp); else #endif outrv = tcp_output_nodrop(tp); out: tcp_bblog_pru(tp, PRU_RCVD, error); TCP_PROBE2(debug__user, tp, PRU_RCVD); (void) tcp_unlock_or_drop(tp, outrv); NET_EPOCH_EXIT(et); return (error); } /* * Do a send by putting data in output queue and updating urgent * marker if URG set. Possibly send more data. Unlike the other * pru_*() routines, the mbuf chains are our responsibility. We * must either enqueue them or free them. The other pru_* routines * generally are caller-frees. */ static int tcp_usr_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam, struct mbuf *control, struct thread *td) { struct epoch_tracker et; int error = 0; struct inpcb *inp; struct tcpcb *tp; #ifdef INET #ifdef INET6 struct sockaddr_in sin; #endif struct sockaddr_in *sinp; #endif #ifdef INET6 struct sockaddr_in6 *sin6; int isipv6; #endif u_int8_t incflagsav; u_char vflagsav; bool restoreflags; inp = sotoinpcb(so); KASSERT(inp != NULL, ("tcp_usr_send: inp == NULL")); INP_WLOCK(inp); if (inp->inp_flags & INP_DROPPED) { if (m != NULL && (flags & PRUS_NOTREADY) == 0) m_freem(m); INP_WUNLOCK(inp); return (ECONNRESET); } tp = intotcpcb(inp); vflagsav = inp->inp_vflag; incflagsav = inp->inp_inc.inc_flags; restoreflags = false; NET_EPOCH_ENTER(et); if (control != NULL) { /* TCP doesn't do control messages (rights, creds, etc) */ if (control->m_len > 0) { m_freem(control); error = EINVAL; goto out; } m_freem(control); /* empty control, just free it */ } if ((flags & PRUS_OOB) != 0 && (error = tcp_pru_options_support(tp, PRUS_OOB)) != 0) goto out; if (nam != NULL && tp->t_state < TCPS_SYN_SENT) { if (tp->t_state == TCPS_LISTEN) { error = EINVAL; goto out; } switch (nam->sa_family) { #ifdef INET case AF_INET: sinp = (struct sockaddr_in *)nam; if (sinp->sin_len != sizeof(struct sockaddr_in)) { error = EINVAL; goto out; } if ((inp->inp_vflag & INP_IPV6) != 0) { error = EAFNOSUPPORT; goto out; } if (IN_MULTICAST(ntohl(sinp->sin_addr.s_addr))) { error = EAFNOSUPPORT; goto out; } if (ntohl(sinp->sin_addr.s_addr) == INADDR_BROADCAST) { error = EACCES; goto out; } if ((error = prison_remote_ip4(td->td_ucred, &sinp->sin_addr))) goto out; #ifdef INET6 isipv6 = 0; #endif break; #endif /* INET */ #ifdef INET6 case AF_INET6: sin6 = (struct sockaddr_in6 *)nam; if (sin6->sin6_len != sizeof(*sin6)) { error = EINVAL; goto out; } if ((inp->inp_vflag & INP_IPV6PROTO) == 0) { error = EAFNOSUPPORT; goto out; } if (IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) { error = EAFNOSUPPORT; goto out; } if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) { #ifdef INET if ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0) { error = EINVAL; goto out; } if ((inp->inp_vflag & INP_IPV4) == 0) { error = EAFNOSUPPORT; goto out; } restoreflags = true; inp->inp_vflag &= ~INP_IPV6; sinp = &sin; in6_sin6_2_sin(sinp, sin6); if (IN_MULTICAST( ntohl(sinp->sin_addr.s_addr))) { error = EAFNOSUPPORT; goto out; } if ((error = prison_remote_ip4(td->td_ucred, &sinp->sin_addr))) goto out; isipv6 = 0; #else /* !INET */ error = EAFNOSUPPORT; goto out; #endif /* INET */ } else { if ((inp->inp_vflag & INP_IPV6) == 0) { error = EAFNOSUPPORT; goto out; } restoreflags = true; inp->inp_vflag &= ~INP_IPV4; inp->inp_inc.inc_flags |= INC_ISIPV6; if ((error = prison_remote_ip6(td->td_ucred, &sin6->sin6_addr))) goto out; isipv6 = 1; } break; #endif /* INET6 */ default: error = EAFNOSUPPORT; goto out; } } if (!(flags & PRUS_OOB)) { if (tp->t_acktime == 0) tp->t_acktime = ticks; sbappendstream(&so->so_snd, m, flags); m = NULL; if (nam && tp->t_state < TCPS_SYN_SENT) { KASSERT(tp->t_state == TCPS_CLOSED, ("%s: tp %p is listening", __func__, tp)); /* * Do implied connect if not yet connected, * initialize window to default value, and * initialize maxseg using peer's cached MSS. */ #ifdef INET6 if (isipv6) error = tcp6_connect(tp, sin6, td); #endif /* INET6 */ #if defined(INET6) && defined(INET) else #endif #ifdef INET error = tcp_connect(tp, sinp, td); #endif /* * The bind operation in tcp_connect succeeded. We * no longer want to restore the flags if later * operations fail. */ if (error == 0 || inp->inp_lport != 0) restoreflags = false; if (error) { /* m is freed if PRUS_NOTREADY is unset. */ sbflush(&so->so_snd); goto out; } if (tp->t_flags & TF_FASTOPEN) tcp_fastopen_connect(tp); else { tp->snd_wnd = TTCP_CLIENT_SND_WND; tcp_mss(tp, -1); } } if (flags & PRUS_EOF) { /* * Close the send side of the connection after * the data is sent. */ socantsendmore(so); tcp_usrclosed(tp); } if (TCPS_HAVEESTABLISHED(tp->t_state) && ((tp->t_flags2 & TF2_FBYTES_COMPLETE) == 0) && (tp->t_fbyte_out == 0) && (so->so_snd.sb_ccc > 0)) { tp->t_fbyte_out = ticks; if (tp->t_fbyte_out == 0) tp->t_fbyte_out = 1; if (tp->t_fbyte_out && tp->t_fbyte_in) tp->t_flags2 |= TF2_FBYTES_COMPLETE; } if (!(inp->inp_flags & INP_DROPPED) && !(flags & PRUS_NOTREADY)) { if (flags & PRUS_MORETOCOME) tp->t_flags |= TF_MORETOCOME; error = tcp_output_nodrop(tp); if (flags & PRUS_MORETOCOME) tp->t_flags &= ~TF_MORETOCOME; } } else { /* * XXXRW: PRUS_EOF not implemented with PRUS_OOB? */ - SOCKBUF_LOCK(&so->so_snd); + SOCK_SENDBUF_LOCK(so); if (sbspace(&so->so_snd) < -512) { - SOCKBUF_UNLOCK(&so->so_snd); + SOCK_SENDBUF_UNLOCK(so); error = ENOBUFS; goto out; } /* * According to RFC961 (Assigned Protocols), * the urgent pointer points to the last octet * of urgent data. We continue, however, * to consider it to indicate the first octet * of data past the urgent section. * Otherwise, snd_up should be one lower. */ if (tp->t_acktime == 0) tp->t_acktime = ticks; sbappendstream_locked(&so->so_snd, m, flags); - SOCKBUF_UNLOCK(&so->so_snd); + SOCK_SENDBUF_UNLOCK(so); m = NULL; if (nam && tp->t_state < TCPS_SYN_SENT) { /* * Do implied connect if not yet connected, * initialize window to default value, and * initialize maxseg using peer's cached MSS. */ /* * Not going to contemplate SYN|URG */ if (tp->t_flags & TF_FASTOPEN) tp->t_flags &= ~TF_FASTOPEN; #ifdef INET6 if (isipv6) error = tcp6_connect(tp, sin6, td); #endif /* INET6 */ #if defined(INET6) && defined(INET) else #endif #ifdef INET error = tcp_connect(tp, sinp, td); #endif /* * The bind operation in tcp_connect succeeded. We * no longer want to restore the flags if later * operations fail. */ if (error == 0 || inp->inp_lport != 0) restoreflags = false; if (error != 0) { /* m is freed if PRUS_NOTREADY is unset. */ sbflush(&so->so_snd); goto out; } tp->snd_wnd = TTCP_CLIENT_SND_WND; tcp_mss(tp, -1); } tp->snd_up = tp->snd_una + sbavail(&so->so_snd); if ((flags & PRUS_NOTREADY) == 0) { tp->t_flags |= TF_FORCEDATA; error = tcp_output_nodrop(tp); tp->t_flags &= ~TF_FORCEDATA; } } TCP_LOG_EVENT(tp, NULL, &inp->inp_socket->so_rcv, &inp->inp_socket->so_snd, TCP_LOG_USERSEND, error, 0, NULL, false); out: /* * In case of PRUS_NOTREADY, the caller or tcp_usr_ready() is * responsible for freeing memory. */ if (m != NULL && (flags & PRUS_NOTREADY) == 0) m_freem(m); /* * If the request was unsuccessful and we changed flags, * restore the original flags. */ if (error != 0 && restoreflags) { inp->inp_vflag = vflagsav; inp->inp_inc.inc_flags = incflagsav; } tcp_bblog_pru(tp, (flags & PRUS_OOB) ? PRU_SENDOOB : ((flags & PRUS_EOF) ? PRU_SEND_EOF : PRU_SEND), error); TCP_PROBE2(debug__user, tp, (flags & PRUS_OOB) ? PRU_SENDOOB : ((flags & PRUS_EOF) ? PRU_SEND_EOF : PRU_SEND)); error = tcp_unlock_or_drop(tp, error); NET_EPOCH_EXIT(et); return (error); } static int tcp_usr_ready(struct socket *so, struct mbuf *m, int count) { struct epoch_tracker et; struct inpcb *inp; struct tcpcb *tp; int error; inp = sotoinpcb(so); INP_WLOCK(inp); if (inp->inp_flags & INP_DROPPED) { INP_WUNLOCK(inp); mb_free_notready(m, count); return (ECONNRESET); } tp = intotcpcb(inp); - SOCKBUF_LOCK(&so->so_snd); + SOCK_SENDBUF_LOCK(so); error = sbready(&so->so_snd, m, count); - SOCKBUF_UNLOCK(&so->so_snd); + SOCK_SENDBUF_UNLOCK(so); if (error) { INP_WUNLOCK(inp); return (error); } NET_EPOCH_ENTER(et); error = tcp_output_unlock(tp); NET_EPOCH_EXIT(et); return (error); } /* * Abort the TCP. Drop the connection abruptly. */ static void tcp_usr_abort(struct socket *so) { struct inpcb *inp; struct tcpcb *tp; struct epoch_tracker et; inp = sotoinpcb(so); KASSERT(inp != NULL, ("tcp_usr_abort: inp == NULL")); NET_EPOCH_ENTER(et); INP_WLOCK(inp); KASSERT(inp->inp_socket != NULL, ("tcp_usr_abort: inp_socket == NULL")); /* * If we still have full TCP state, and we're not dropped, drop. */ if (!(inp->inp_flags & INP_DROPPED)) { tp = intotcpcb(inp); tp = tcp_drop(tp, ECONNABORTED); if (tp == NULL) goto dropped; tcp_bblog_pru(tp, PRU_ABORT, 0); TCP_PROBE2(debug__user, tp, PRU_ABORT); } if (!(inp->inp_flags & INP_DROPPED)) { soref(so); inp->inp_flags |= INP_SOCKREF; } INP_WUNLOCK(inp); dropped: NET_EPOCH_EXIT(et); } /* * TCP socket is closed. Start friendly disconnect. */ static void tcp_usr_close(struct socket *so) { struct inpcb *inp; struct tcpcb *tp; struct epoch_tracker et; inp = sotoinpcb(so); KASSERT(inp != NULL, ("tcp_usr_close: inp == NULL")); NET_EPOCH_ENTER(et); INP_WLOCK(inp); KASSERT(inp->inp_socket != NULL, ("tcp_usr_close: inp_socket == NULL")); /* * If we are still connected and we're not dropped, initiate * a disconnect. */ if (!(inp->inp_flags & INP_DROPPED)) { tp = intotcpcb(inp); if (tp->t_state != TCPS_TIME_WAIT) { tp->t_flags |= TF_CLOSED; tcp_disconnect(tp); tcp_bblog_pru(tp, PRU_CLOSE, 0); TCP_PROBE2(debug__user, tp, PRU_CLOSE); } } if (!(inp->inp_flags & INP_DROPPED)) { soref(so); inp->inp_flags |= INP_SOCKREF; } INP_WUNLOCK(inp); NET_EPOCH_EXIT(et); } static int tcp_pru_options_support(struct tcpcb *tp, int flags) { /* * If the specific TCP stack has a pru_options * specified then it does not always support * all the PRU_XX options and we must ask it. * If the function is not specified then all * of the PRU_XX options are supported. */ int ret = 0; if (tp->t_fb->tfb_pru_options) { ret = (*tp->t_fb->tfb_pru_options)(tp, flags); } return (ret); } /* * Receive out-of-band data. */ static int tcp_usr_rcvoob(struct socket *so, struct mbuf *m, int flags) { int error = 0; struct inpcb *inp; struct tcpcb *tp; inp = sotoinpcb(so); KASSERT(inp != NULL, ("tcp_usr_rcvoob: inp == NULL")); INP_WLOCK(inp); if (inp->inp_flags & INP_DROPPED) { INP_WUNLOCK(inp); return (ECONNRESET); } tp = intotcpcb(inp); error = tcp_pru_options_support(tp, PRUS_OOB); if (error) { goto out; } if ((so->so_oobmark == 0 && (so->so_rcv.sb_state & SBS_RCVATMARK) == 0) || so->so_options & SO_OOBINLINE || tp->t_oobflags & TCPOOB_HADDATA) { error = EINVAL; goto out; } if ((tp->t_oobflags & TCPOOB_HAVEDATA) == 0) { error = EWOULDBLOCK; goto out; } m->m_len = 1; *mtod(m, caddr_t) = tp->t_iobc; if ((flags & MSG_PEEK) == 0) tp->t_oobflags ^= (TCPOOB_HAVEDATA | TCPOOB_HADDATA); out: tcp_bblog_pru(tp, PRU_RCVOOB, error); TCP_PROBE2(debug__user, tp, PRU_RCVOOB); INP_WUNLOCK(inp); return (error); } #ifdef INET struct protosw tcp_protosw = { .pr_type = SOCK_STREAM, .pr_protocol = IPPROTO_TCP, .pr_flags = PR_CONNREQUIRED | PR_IMPLOPCL | PR_WANTRCVD | PR_CAPATTACH, .pr_ctloutput = tcp_ctloutput, .pr_abort = tcp_usr_abort, .pr_accept = tcp_usr_accept, .pr_attach = tcp_usr_attach, .pr_bind = tcp_usr_bind, .pr_connect = tcp_usr_connect, .pr_control = in_control, .pr_detach = tcp_usr_detach, .pr_disconnect = tcp_usr_disconnect, .pr_listen = tcp_usr_listen, .pr_peeraddr = in_getpeeraddr, .pr_rcvd = tcp_usr_rcvd, .pr_rcvoob = tcp_usr_rcvoob, .pr_send = tcp_usr_send, .pr_ready = tcp_usr_ready, .pr_shutdown = tcp_usr_shutdown, .pr_sockaddr = in_getsockaddr, .pr_sosetlabel = in_pcbsosetlabel, .pr_close = tcp_usr_close, }; #endif /* INET */ #ifdef INET6 struct protosw tcp6_protosw = { .pr_type = SOCK_STREAM, .pr_protocol = IPPROTO_TCP, .pr_flags = PR_CONNREQUIRED | PR_IMPLOPCL |PR_WANTRCVD | PR_CAPATTACH, .pr_ctloutput = tcp_ctloutput, .pr_abort = tcp_usr_abort, .pr_accept = tcp6_usr_accept, .pr_attach = tcp_usr_attach, .pr_bind = tcp6_usr_bind, .pr_connect = tcp6_usr_connect, .pr_control = in6_control, .pr_detach = tcp_usr_detach, .pr_disconnect = tcp_usr_disconnect, .pr_listen = tcp6_usr_listen, .pr_peeraddr = in6_mapped_peeraddr, .pr_rcvd = tcp_usr_rcvd, .pr_rcvoob = tcp_usr_rcvoob, .pr_send = tcp_usr_send, .pr_ready = tcp_usr_ready, .pr_shutdown = tcp_usr_shutdown, .pr_sockaddr = in6_mapped_sockaddr, .pr_sosetlabel = in_pcbsosetlabel, .pr_close = tcp_usr_close, }; #endif /* INET6 */ #ifdef INET /* * Common subroutine to open a TCP connection to remote host specified * by struct sockaddr_in. Call in_pcbconnect() to choose local host address * and assign a local port number and install the inpcb into the hash. * Initialize connection parameters and enter SYN-SENT state. */ static int tcp_connect(struct tcpcb *tp, struct sockaddr_in *sin, struct thread *td) { struct inpcb *inp = tptoinpcb(tp); struct socket *so = tptosocket(tp); int error; NET_EPOCH_ASSERT(); INP_WLOCK_ASSERT(inp); if (__predict_false((so->so_state & (SS_ISCONNECTING | SS_ISCONNECTED | SS_ISDISCONNECTING | SS_ISDISCONNECTED)) != 0)) return (EISCONN); INP_HASH_WLOCK(&V_tcbinfo); error = in_pcbconnect(inp, sin, td->td_ucred, true); INP_HASH_WUNLOCK(&V_tcbinfo); if (error != 0) return (error); /* * Compute window scaling to request: * Scale to fit into sweet spot. See tcp_syncache.c. * XXX: This should move to tcp_output(). */ while (tp->request_r_scale < TCP_MAX_WINSHIFT && (TCP_MAXWIN << tp->request_r_scale) < sb_max) tp->request_r_scale++; soisconnecting(so); TCPSTAT_INC(tcps_connattempt); tcp_state_change(tp, TCPS_SYN_SENT); tp->iss = tcp_new_isn(&inp->inp_inc); if (tp->t_flags & TF_REQ_TSTMP) tp->ts_offset = tcp_new_ts_offset(&inp->inp_inc); tcp_sendseqinit(tp); return (0); } #endif /* INET */ #ifdef INET6 static int tcp6_connect(struct tcpcb *tp, struct sockaddr_in6 *sin6, struct thread *td) { struct inpcb *inp = tptoinpcb(tp); struct socket *so = tptosocket(tp); int error; NET_EPOCH_ASSERT(); INP_WLOCK_ASSERT(inp); if (__predict_false((so->so_state & (SS_ISCONNECTING | SS_ISCONNECTED)) != 0)) return (EISCONN); INP_HASH_WLOCK(&V_tcbinfo); error = in6_pcbconnect(inp, sin6, td->td_ucred, true); INP_HASH_WUNLOCK(&V_tcbinfo); if (error != 0) return (error); /* Compute window scaling to request. */ while (tp->request_r_scale < TCP_MAX_WINSHIFT && (TCP_MAXWIN << tp->request_r_scale) < sb_max) tp->request_r_scale++; soisconnecting(so); TCPSTAT_INC(tcps_connattempt); tcp_state_change(tp, TCPS_SYN_SENT); tp->iss = tcp_new_isn(&inp->inp_inc); if (tp->t_flags & TF_REQ_TSTMP) tp->ts_offset = tcp_new_ts_offset(&inp->inp_inc); tcp_sendseqinit(tp); return (0); } #endif /* INET6 */ /* * Export TCP internal state information via a struct tcp_info, based on the * Linux 2.6 API. Not ABI compatible as our constants are mapped differently * (TCP state machine, etc). We export all information using FreeBSD-native * constants -- for example, the numeric values for tcpi_state will differ * from Linux. */ void tcp_fill_info(const struct tcpcb *tp, struct tcp_info *ti) { INP_LOCK_ASSERT(tptoinpcb(tp)); bzero(ti, sizeof(*ti)); ti->tcpi_state = tp->t_state; if ((tp->t_flags & TF_REQ_TSTMP) && (tp->t_flags & TF_RCVD_TSTMP)) ti->tcpi_options |= TCPI_OPT_TIMESTAMPS; if (tp->t_flags & TF_SACK_PERMIT) ti->tcpi_options |= TCPI_OPT_SACK; if ((tp->t_flags & TF_REQ_SCALE) && (tp->t_flags & TF_RCVD_SCALE)) { ti->tcpi_options |= TCPI_OPT_WSCALE; ti->tcpi_snd_wscale = tp->snd_scale; ti->tcpi_rcv_wscale = tp->rcv_scale; } switch (tp->t_flags2 & (TF2_ECN_PERMIT | TF2_ACE_PERMIT)) { case TF2_ECN_PERMIT: ti->tcpi_options |= TCPI_OPT_ECN; break; case TF2_ACE_PERMIT: /* FALLTHROUGH */ case TF2_ECN_PERMIT | TF2_ACE_PERMIT: ti->tcpi_options |= TCPI_OPT_ACE; break; default: break; } if (tp->t_flags & TF_FASTOPEN) ti->tcpi_options |= TCPI_OPT_TFO; ti->tcpi_rto = tp->t_rxtcur * tick; ti->tcpi_last_data_recv = ((uint32_t)ticks - tp->t_rcvtime) * tick; ti->tcpi_rtt = ((u_int64_t)tp->t_srtt * tick) >> TCP_RTT_SHIFT; ti->tcpi_rttvar = ((u_int64_t)tp->t_rttvar * tick) >> TCP_RTTVAR_SHIFT; ti->tcpi_snd_ssthresh = tp->snd_ssthresh; ti->tcpi_snd_cwnd = tp->snd_cwnd; /* * FreeBSD-specific extension fields for tcp_info. */ ti->tcpi_rcv_space = tp->rcv_wnd; ti->tcpi_rcv_nxt = tp->rcv_nxt; ti->tcpi_snd_wnd = tp->snd_wnd; ti->tcpi_snd_bwnd = 0; /* Unused, kept for compat. */ ti->tcpi_snd_nxt = tp->snd_nxt; ti->tcpi_snd_mss = tp->t_maxseg; ti->tcpi_rcv_mss = tp->t_maxseg; ti->tcpi_snd_rexmitpack = tp->t_sndrexmitpack; ti->tcpi_rcv_ooopack = tp->t_rcvoopack; ti->tcpi_snd_zerowin = tp->t_sndzerowin; ti->tcpi_snd_una = tp->snd_una; ti->tcpi_snd_max = tp->snd_max; ti->tcpi_rcv_numsacks = tp->rcv_numsacks; ti->tcpi_rcv_adv = tp->rcv_adv; ti->tcpi_dupacks = tp->t_dupacks; ti->tcpi_rttmin = tp->t_rttlow; #ifdef TCP_OFFLOAD if (tp->t_flags & TF_TOE) { ti->tcpi_options |= TCPI_OPT_TOE; tcp_offload_tcp_info(tp, ti); } #endif /* * AccECN related counters. */ if ((tp->t_flags2 & (TF2_ECN_PERMIT | TF2_ACE_PERMIT)) == (TF2_ECN_PERMIT | TF2_ACE_PERMIT)) /* * Internal counter starts at 5 for AccECN * but 0 for RFC3168 ECN. */ ti->tcpi_delivered_ce = tp->t_scep - 5; else ti->tcpi_delivered_ce = tp->t_scep; ti->tcpi_received_ce = tp->t_rcep; } /* * tcp_ctloutput() must drop the inpcb lock before performing copyin on * socket option arguments. When it re-acquires the lock after the copy, it * has to revalidate that the connection is still valid for the socket * option. */ #define INP_WLOCK_RECHECK_CLEANUP(inp, cleanup) do { \ INP_WLOCK(inp); \ if (inp->inp_flags & INP_DROPPED) { \ INP_WUNLOCK(inp); \ cleanup; \ return (ECONNRESET); \ } \ tp = intotcpcb(inp); \ } while(0) #define INP_WLOCK_RECHECK(inp) INP_WLOCK_RECHECK_CLEANUP((inp), /* noop */) int tcp_ctloutput_set(struct inpcb *inp, struct sockopt *sopt) { struct socket *so = inp->inp_socket; struct tcpcb *tp = intotcpcb(inp); int error = 0; MPASS(sopt->sopt_dir == SOPT_SET); INP_WLOCK_ASSERT(inp); KASSERT((inp->inp_flags & INP_DROPPED) == 0, ("inp_flags == %x", inp->inp_flags)); KASSERT(so != NULL, ("inp_socket == NULL")); if (sopt->sopt_level != IPPROTO_TCP) { INP_WUNLOCK(inp); #ifdef INET6 if (inp->inp_vflag & INP_IPV6PROTO) error = ip6_ctloutput(so, sopt); #endif #if defined(INET6) && defined(INET) else #endif #ifdef INET error = ip_ctloutput(so, sopt); #endif /* * When an IP-level socket option affects TCP, pass control * down to stack tfb_tcp_ctloutput, otherwise return what * IP level returned. */ switch (sopt->sopt_level) { #ifdef INET6 case IPPROTO_IPV6: if ((inp->inp_vflag & INP_IPV6PROTO) == 0) return (error); switch (sopt->sopt_name) { case IPV6_TCLASS: /* Notify tcp stacks that care (e.g. RACK). */ break; case IPV6_USE_MIN_MTU: /* Update t_maxseg accordingly. */ break; default: return (error); } break; #endif #ifdef INET case IPPROTO_IP: switch (sopt->sopt_name) { case IP_TOS: inp->inp_ip_tos &= ~IPTOS_ECN_MASK; break; case IP_TTL: /* Notify tcp stacks that care (e.g. RACK). */ break; default: return (error); } break; #endif default: return (error); } INP_WLOCK_RECHECK(inp); } else if (sopt->sopt_name == TCP_FUNCTION_BLK) { /* * Protect the TCP option TCP_FUNCTION_BLK so * that a sub-function can *never* overwrite this. */ struct tcp_function_set fsn; struct tcp_function_block *blk; void *ptr = NULL; INP_WUNLOCK(inp); error = sooptcopyin(sopt, &fsn, sizeof fsn, sizeof fsn); if (error) return (error); INP_WLOCK_RECHECK(inp); blk = find_and_ref_tcp_functions(&fsn); if (blk == NULL) { INP_WUNLOCK(inp); return (ENOENT); } if (tp->t_fb == blk) { /* You already have this */ refcount_release(&blk->tfb_refcnt); INP_WUNLOCK(inp); return (0); } if (blk->tfb_flags & TCP_FUNC_BEING_REMOVED) { refcount_release(&blk->tfb_refcnt); INP_WUNLOCK(inp); return (ENOENT); } error = (*blk->tfb_tcp_handoff_ok)(tp); if (error) { refcount_release(&blk->tfb_refcnt); INP_WUNLOCK(inp); return (error); } /* * Ensure the new stack takes ownership with a * clean slate on peak rate threshold. */ if (tp->t_fb->tfb_tcp_timer_stop_all != NULL) tp->t_fb->tfb_tcp_timer_stop_all(tp); if (blk->tfb_tcp_fb_init) { error = (*blk->tfb_tcp_fb_init)(tp, &ptr); if (error) { /* * Release the ref count the lookup * acquired. */ refcount_release(&blk->tfb_refcnt); /* * Now there is a chance that the * init() function mucked with some * things before it failed, such as * hpts or inp_flags2 or timer granularity. * It should not of, but lets give the old * stack a chance to reset to a known good state. */ if (tp->t_fb->tfb_switch_failed) { (*tp->t_fb->tfb_switch_failed)(tp); } goto err_out; } } if (tp->t_fb->tfb_tcp_fb_fini) { struct epoch_tracker et; /* * Tell the stack to cleanup with 0 i.e. * the tcb is not going away. */ NET_EPOCH_ENTER(et); (*tp->t_fb->tfb_tcp_fb_fini)(tp, 0); NET_EPOCH_EXIT(et); } /* * Release the old refcnt, the * lookup acquired a ref on the * new one already. */ refcount_release(&tp->t_fb->tfb_refcnt); /* * Set in the new stack. */ tp->t_fb = blk; tp->t_fb_ptr = ptr; #ifdef TCP_OFFLOAD if (tp->t_flags & TF_TOE) { tcp_offload_ctloutput(tp, sopt->sopt_dir, sopt->sopt_name); } #endif err_out: INP_WUNLOCK(inp); return (error); } /* Pass in the INP locked, callee must unlock it. */ return (tp->t_fb->tfb_tcp_ctloutput(tp, sopt)); } static int tcp_ctloutput_get(struct inpcb *inp, struct sockopt *sopt) { struct socket *so = inp->inp_socket; struct tcpcb *tp = intotcpcb(inp); int error = 0; MPASS(sopt->sopt_dir == SOPT_GET); INP_WLOCK_ASSERT(inp); KASSERT((inp->inp_flags & INP_DROPPED) == 0, ("inp_flags == %x", inp->inp_flags)); KASSERT(so != NULL, ("inp_socket == NULL")); if (sopt->sopt_level != IPPROTO_TCP) { INP_WUNLOCK(inp); #ifdef INET6 if (inp->inp_vflag & INP_IPV6PROTO) error = ip6_ctloutput(so, sopt); #endif /* INET6 */ #if defined(INET6) && defined(INET) else #endif #ifdef INET error = ip_ctloutput(so, sopt); #endif return (error); } if (((sopt->sopt_name == TCP_FUNCTION_BLK) || (sopt->sopt_name == TCP_FUNCTION_ALIAS))) { struct tcp_function_set fsn; if (sopt->sopt_name == TCP_FUNCTION_ALIAS) { memset(&fsn, 0, sizeof(fsn)); find_tcp_function_alias(tp->t_fb, &fsn); } else { strncpy(fsn.function_set_name, tp->t_fb->tfb_tcp_block_name, TCP_FUNCTION_NAME_LEN_MAX); fsn.function_set_name[TCP_FUNCTION_NAME_LEN_MAX - 1] = '\0'; } fsn.pcbcnt = tp->t_fb->tfb_refcnt; INP_WUNLOCK(inp); error = sooptcopyout(sopt, &fsn, sizeof fsn); return (error); } /* Pass in the INP locked, callee must unlock it. */ return (tp->t_fb->tfb_tcp_ctloutput(tp, sopt)); } int tcp_ctloutput(struct socket *so, struct sockopt *sopt) { struct inpcb *inp; inp = sotoinpcb(so); KASSERT(inp != NULL, ("tcp_ctloutput: inp == NULL")); INP_WLOCK(inp); if (inp->inp_flags & INP_DROPPED) { INP_WUNLOCK(inp); return (ECONNRESET); } if (sopt->sopt_dir == SOPT_SET) return (tcp_ctloutput_set(inp, sopt)); else if (sopt->sopt_dir == SOPT_GET) return (tcp_ctloutput_get(inp, sopt)); else panic("%s: sopt_dir $%d", __func__, sopt->sopt_dir); } /* * If this assert becomes untrue, we need to change the size of the buf * variable in tcp_default_ctloutput(). */ #ifdef CTASSERT CTASSERT(TCP_CA_NAME_MAX <= TCP_LOG_ID_LEN); CTASSERT(TCP_LOG_REASON_LEN <= TCP_LOG_ID_LEN); #endif extern struct cc_algo newreno_cc_algo; static int tcp_set_cc_mod(struct inpcb *inp, struct sockopt *sopt) { struct cc_algo *algo; void *ptr = NULL; struct tcpcb *tp; struct cc_var cc_mem; char buf[TCP_CA_NAME_MAX]; size_t mem_sz; int error; INP_WUNLOCK(inp); error = sooptcopyin(sopt, buf, TCP_CA_NAME_MAX - 1, 1); if (error) return(error); buf[sopt->sopt_valsize] = '\0'; CC_LIST_RLOCK(); STAILQ_FOREACH(algo, &cc_list, entries) { if (strncmp(buf, algo->name, TCP_CA_NAME_MAX) == 0) { if (algo->flags & CC_MODULE_BEING_REMOVED) { /* We can't "see" modules being unloaded */ continue; } break; } } if (algo == NULL) { CC_LIST_RUNLOCK(); return(ESRCH); } /* * With a reference the algorithm cannot be removed * so we hold a reference through the change process. */ cc_refer(algo); CC_LIST_RUNLOCK(); if (algo->cb_init != NULL) { /* We can now pre-get the memory for the CC */ mem_sz = (*algo->cc_data_sz)(); if (mem_sz == 0) { goto no_mem_needed; } ptr = malloc(mem_sz, M_CC_MEM, M_WAITOK); } else { no_mem_needed: mem_sz = 0; ptr = NULL; } /* * Make sure its all clean and zero and also get * back the inplock. */ memset(&cc_mem, 0, sizeof(cc_mem)); INP_WLOCK(inp); if (inp->inp_flags & INP_DROPPED) { INP_WUNLOCK(inp); if (ptr) free(ptr, M_CC_MEM); /* Release our temp reference */ CC_LIST_RLOCK(); cc_release(algo); CC_LIST_RUNLOCK(); return (ECONNRESET); } tp = intotcpcb(inp); if (ptr != NULL) memset(ptr, 0, mem_sz); cc_mem.tp = tp; /* * We once again hold a write lock over the tcb so it's * safe to do these things without ordering concerns. * Note here we init into stack memory. */ if (algo->cb_init != NULL) error = algo->cb_init(&cc_mem, ptr); else error = 0; /* * The CC algorithms, when given their memory * should not fail we could in theory have a * KASSERT here. */ if (error == 0) { /* * Touchdown, lets go ahead and move the * connection to the new CC module by * copying in the cc_mem after we call * the old ones cleanup (if any). */ if (CC_ALGO(tp)->cb_destroy != NULL) CC_ALGO(tp)->cb_destroy(&tp->t_ccv); /* Detach the old CC from the tcpcb */ cc_detach(tp); /* Copy in our temp memory that was inited */ memcpy(&tp->t_ccv, &cc_mem, sizeof(struct cc_var)); /* Now attach the new, which takes a reference */ cc_attach(tp, algo); /* Ok now are we where we have gotten past any conn_init? */ if (TCPS_HAVEESTABLISHED(tp->t_state) && (CC_ALGO(tp)->conn_init != NULL)) { /* Yep run the connection init for the new CC */ CC_ALGO(tp)->conn_init(&tp->t_ccv); } } else if (ptr) free(ptr, M_CC_MEM); INP_WUNLOCK(inp); /* Now lets release our temp reference */ CC_LIST_RLOCK(); cc_release(algo); CC_LIST_RUNLOCK(); return (error); } int tcp_default_ctloutput(struct tcpcb *tp, struct sockopt *sopt) { struct inpcb *inp = tptoinpcb(tp); int error, opt, optval; u_int ui; struct tcp_info ti; #ifdef KERN_TLS struct tls_enable tls; struct socket *so = inp->inp_socket; #endif char *pbuf, buf[TCP_LOG_ID_LEN]; #ifdef STATS struct statsblob *sbp; #endif size_t len; INP_WLOCK_ASSERT(inp); KASSERT((inp->inp_flags & INP_DROPPED) == 0, ("inp_flags == %x", inp->inp_flags)); KASSERT(inp->inp_socket != NULL, ("inp_socket == NULL")); switch (sopt->sopt_level) { #ifdef INET6 case IPPROTO_IPV6: MPASS(inp->inp_vflag & INP_IPV6PROTO); switch (sopt->sopt_name) { case IPV6_USE_MIN_MTU: tcp6_use_min_mtu(tp); /* FALLTHROUGH */ } INP_WUNLOCK(inp); return (0); #endif #ifdef INET case IPPROTO_IP: INP_WUNLOCK(inp); return (0); #endif } /* * For TCP_CCALGOOPT forward the control to CC module, for both * SOPT_SET and SOPT_GET. */ switch (sopt->sopt_name) { case TCP_CCALGOOPT: INP_WUNLOCK(inp); if (sopt->sopt_valsize > CC_ALGOOPT_LIMIT) return (EINVAL); pbuf = malloc(sopt->sopt_valsize, M_TEMP, M_WAITOK | M_ZERO); error = sooptcopyin(sopt, pbuf, sopt->sopt_valsize, sopt->sopt_valsize); if (error) { free(pbuf, M_TEMP); return (error); } INP_WLOCK_RECHECK_CLEANUP(inp, free(pbuf, M_TEMP)); if (CC_ALGO(tp)->ctl_output != NULL) error = CC_ALGO(tp)->ctl_output(&tp->t_ccv, sopt, pbuf); else error = ENOENT; INP_WUNLOCK(inp); if (error == 0 && sopt->sopt_dir == SOPT_GET) error = sooptcopyout(sopt, pbuf, sopt->sopt_valsize); free(pbuf, M_TEMP); return (error); } switch (sopt->sopt_dir) { case SOPT_SET: switch (sopt->sopt_name) { #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) case TCP_MD5SIG: INP_WUNLOCK(inp); if (!TCPMD5_ENABLED()) return (ENOPROTOOPT); error = TCPMD5_PCBCTL(inp, sopt); if (error) return (error); INP_WLOCK_RECHECK(inp); goto unlock_and_done; #endif /* IPSEC */ case TCP_NODELAY: case TCP_NOOPT: INP_WUNLOCK(inp); error = sooptcopyin(sopt, &optval, sizeof optval, sizeof optval); if (error) return (error); INP_WLOCK_RECHECK(inp); switch (sopt->sopt_name) { case TCP_NODELAY: opt = TF_NODELAY; break; case TCP_NOOPT: opt = TF_NOOPT; break; default: opt = 0; /* dead code to fool gcc */ break; } if (optval) tp->t_flags |= opt; else tp->t_flags &= ~opt; unlock_and_done: #ifdef TCP_OFFLOAD if (tp->t_flags & TF_TOE) { tcp_offload_ctloutput(tp, sopt->sopt_dir, sopt->sopt_name); } #endif INP_WUNLOCK(inp); break; case TCP_NOPUSH: INP_WUNLOCK(inp); error = sooptcopyin(sopt, &optval, sizeof optval, sizeof optval); if (error) return (error); INP_WLOCK_RECHECK(inp); if (optval) tp->t_flags |= TF_NOPUSH; else if (tp->t_flags & TF_NOPUSH) { tp->t_flags &= ~TF_NOPUSH; if (TCPS_HAVEESTABLISHED(tp->t_state)) { struct epoch_tracker et; NET_EPOCH_ENTER(et); error = tcp_output_nodrop(tp); NET_EPOCH_EXIT(et); } } goto unlock_and_done; case TCP_REMOTE_UDP_ENCAPS_PORT: INP_WUNLOCK(inp); error = sooptcopyin(sopt, &optval, sizeof optval, sizeof optval); if (error) return (error); if ((optval < TCP_TUNNELING_PORT_MIN) || (optval > TCP_TUNNELING_PORT_MAX)) { /* Its got to be in range */ return (EINVAL); } if ((V_tcp_udp_tunneling_port == 0) && (optval != 0)) { /* You have to have enabled a UDP tunneling port first */ return (EINVAL); } INP_WLOCK_RECHECK(inp); if (tp->t_state != TCPS_CLOSED) { /* You can't change after you are connected */ error = EINVAL; } else { /* Ok we are all good set the port */ tp->t_port = htons(optval); } goto unlock_and_done; case TCP_MAXSEG: INP_WUNLOCK(inp); error = sooptcopyin(sopt, &optval, sizeof optval, sizeof optval); if (error) return (error); INP_WLOCK_RECHECK(inp); if (optval > 0 && optval <= tp->t_maxseg && optval + 40 >= V_tcp_minmss) { tp->t_maxseg = optval; if (tp->t_maxseg < V_tcp_mssdflt) { /* * The MSS is so small we should not process incoming * SACK's since we are subject to attack in such a * case. */ tp->t_flags2 |= TF2_PROC_SACK_PROHIBIT; } else { tp->t_flags2 &= ~TF2_PROC_SACK_PROHIBIT; } } else error = EINVAL; goto unlock_and_done; case TCP_INFO: INP_WUNLOCK(inp); error = EINVAL; break; case TCP_STATS: INP_WUNLOCK(inp); #ifdef STATS error = sooptcopyin(sopt, &optval, sizeof optval, sizeof optval); if (error) return (error); if (optval > 0) sbp = stats_blob_alloc( V_tcp_perconn_stats_dflt_tpl, 0); else sbp = NULL; INP_WLOCK_RECHECK(inp); if ((tp->t_stats != NULL && sbp == NULL) || (tp->t_stats == NULL && sbp != NULL)) { struct statsblob *t = tp->t_stats; tp->t_stats = sbp; sbp = t; } INP_WUNLOCK(inp); stats_blob_destroy(sbp); #else return (EOPNOTSUPP); #endif /* !STATS */ break; case TCP_CONGESTION: error = tcp_set_cc_mod(inp, sopt); break; case TCP_REUSPORT_LB_NUMA: INP_WUNLOCK(inp); error = sooptcopyin(sopt, &optval, sizeof(optval), sizeof(optval)); INP_WLOCK_RECHECK(inp); if (!error) error = in_pcblbgroup_numa(inp, optval); INP_WUNLOCK(inp); break; #ifdef KERN_TLS case TCP_TXTLS_ENABLE: INP_WUNLOCK(inp); error = ktls_copyin_tls_enable(sopt, &tls); if (error != 0) break; error = ktls_enable_tx(so, &tls); ktls_cleanup_tls_enable(&tls); break; case TCP_TXTLS_MODE: INP_WUNLOCK(inp); error = sooptcopyin(sopt, &ui, sizeof(ui), sizeof(ui)); if (error != 0) return (error); INP_WLOCK_RECHECK(inp); error = ktls_set_tx_mode(so, ui); INP_WUNLOCK(inp); break; case TCP_RXTLS_ENABLE: INP_WUNLOCK(inp); error = ktls_copyin_tls_enable(sopt, &tls); if (error != 0) break; error = ktls_enable_rx(so, &tls); ktls_cleanup_tls_enable(&tls); break; #endif case TCP_MAXUNACKTIME: case TCP_KEEPIDLE: case TCP_KEEPINTVL: case TCP_KEEPINIT: INP_WUNLOCK(inp); error = sooptcopyin(sopt, &ui, sizeof(ui), sizeof(ui)); if (error) return (error); if (ui > (UINT_MAX / hz)) { error = EINVAL; break; } ui *= hz; INP_WLOCK_RECHECK(inp); switch (sopt->sopt_name) { case TCP_MAXUNACKTIME: tp->t_maxunacktime = ui; break; case TCP_KEEPIDLE: tp->t_keepidle = ui; /* * XXX: better check current remaining * timeout and "merge" it with new value. */ if ((tp->t_state > TCPS_LISTEN) && (tp->t_state <= TCPS_CLOSING)) tcp_timer_activate(tp, TT_KEEP, TP_KEEPIDLE(tp)); break; case TCP_KEEPINTVL: tp->t_keepintvl = ui; if ((tp->t_state == TCPS_FIN_WAIT_2) && (TP_MAXIDLE(tp) > 0)) tcp_timer_activate(tp, TT_2MSL, TP_MAXIDLE(tp)); break; case TCP_KEEPINIT: tp->t_keepinit = ui; if (tp->t_state == TCPS_SYN_RECEIVED || tp->t_state == TCPS_SYN_SENT) tcp_timer_activate(tp, TT_KEEP, TP_KEEPINIT(tp)); break; } goto unlock_and_done; case TCP_KEEPCNT: INP_WUNLOCK(inp); error = sooptcopyin(sopt, &ui, sizeof(ui), sizeof(ui)); if (error) return (error); INP_WLOCK_RECHECK(inp); tp->t_keepcnt = ui; if ((tp->t_state == TCPS_FIN_WAIT_2) && (TP_MAXIDLE(tp) > 0)) tcp_timer_activate(tp, TT_2MSL, TP_MAXIDLE(tp)); goto unlock_and_done; #ifdef TCPPCAP case TCP_PCAP_OUT: case TCP_PCAP_IN: INP_WUNLOCK(inp); error = sooptcopyin(sopt, &optval, sizeof optval, sizeof optval); if (error) return (error); INP_WLOCK_RECHECK(inp); if (optval >= 0) tcp_pcap_set_sock_max( (sopt->sopt_name == TCP_PCAP_OUT) ? &(tp->t_outpkts) : &(tp->t_inpkts), optval); else error = EINVAL; goto unlock_and_done; #endif case TCP_FASTOPEN: { struct tcp_fastopen tfo_optval; INP_WUNLOCK(inp); if (!V_tcp_fastopen_client_enable && !V_tcp_fastopen_server_enable) return (EPERM); error = sooptcopyin(sopt, &tfo_optval, sizeof(tfo_optval), sizeof(int)); if (error) return (error); INP_WLOCK_RECHECK(inp); if ((tp->t_state != TCPS_CLOSED) && (tp->t_state != TCPS_LISTEN)) { error = EINVAL; goto unlock_and_done; } if (tfo_optval.enable) { if (tp->t_state == TCPS_LISTEN) { if (!V_tcp_fastopen_server_enable) { error = EPERM; goto unlock_and_done; } if (tp->t_tfo_pending == NULL) tp->t_tfo_pending = tcp_fastopen_alloc_counter(); } else { /* * If a pre-shared key was provided, * stash it in the client cookie * field of the tcpcb for use during * connect. */ if (sopt->sopt_valsize == sizeof(tfo_optval)) { memcpy(tp->t_tfo_cookie.client, tfo_optval.psk, TCP_FASTOPEN_PSK_LEN); tp->t_tfo_client_cookie_len = TCP_FASTOPEN_PSK_LEN; } } tp->t_flags |= TF_FASTOPEN; } else tp->t_flags &= ~TF_FASTOPEN; goto unlock_and_done; } #ifdef TCP_BLACKBOX case TCP_LOG: INP_WUNLOCK(inp); error = sooptcopyin(sopt, &optval, sizeof optval, sizeof optval); if (error) return (error); INP_WLOCK_RECHECK(inp); error = tcp_log_state_change(tp, optval); goto unlock_and_done; case TCP_LOGBUF: INP_WUNLOCK(inp); error = EINVAL; break; case TCP_LOGID: INP_WUNLOCK(inp); error = sooptcopyin(sopt, buf, TCP_LOG_ID_LEN - 1, 0); if (error) break; buf[sopt->sopt_valsize] = '\0'; INP_WLOCK_RECHECK(inp); error = tcp_log_set_id(tp, buf); /* tcp_log_set_id() unlocks the INP. */ break; case TCP_LOGDUMP: case TCP_LOGDUMPID: INP_WUNLOCK(inp); error = sooptcopyin(sopt, buf, TCP_LOG_REASON_LEN - 1, 0); if (error) break; buf[sopt->sopt_valsize] = '\0'; INP_WLOCK_RECHECK(inp); if (sopt->sopt_name == TCP_LOGDUMP) { error = tcp_log_dump_tp_logbuf(tp, buf, M_WAITOK, true); INP_WUNLOCK(inp); } else { tcp_log_dump_tp_bucket_logbufs(tp, buf); /* * tcp_log_dump_tp_bucket_logbufs() drops the * INP lock. */ } break; #endif default: INP_WUNLOCK(inp); error = ENOPROTOOPT; break; } break; case SOPT_GET: tp = intotcpcb(inp); switch (sopt->sopt_name) { #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) case TCP_MD5SIG: INP_WUNLOCK(inp); if (!TCPMD5_ENABLED()) return (ENOPROTOOPT); error = TCPMD5_PCBCTL(inp, sopt); break; #endif case TCP_NODELAY: optval = tp->t_flags & TF_NODELAY; INP_WUNLOCK(inp); error = sooptcopyout(sopt, &optval, sizeof optval); break; case TCP_MAXSEG: optval = tp->t_maxseg; INP_WUNLOCK(inp); error = sooptcopyout(sopt, &optval, sizeof optval); break; case TCP_REMOTE_UDP_ENCAPS_PORT: optval = ntohs(tp->t_port); INP_WUNLOCK(inp); error = sooptcopyout(sopt, &optval, sizeof optval); break; case TCP_NOOPT: optval = tp->t_flags & TF_NOOPT; INP_WUNLOCK(inp); error = sooptcopyout(sopt, &optval, sizeof optval); break; case TCP_NOPUSH: optval = tp->t_flags & TF_NOPUSH; INP_WUNLOCK(inp); error = sooptcopyout(sopt, &optval, sizeof optval); break; case TCP_INFO: tcp_fill_info(tp, &ti); INP_WUNLOCK(inp); error = sooptcopyout(sopt, &ti, sizeof ti); break; case TCP_STATS: { #ifdef STATS int nheld; TYPEOF_MEMBER(struct statsblob, flags) sbflags = 0; error = 0; socklen_t outsbsz = sopt->sopt_valsize; if (tp->t_stats == NULL) error = ENOENT; else if (outsbsz >= tp->t_stats->cursz) outsbsz = tp->t_stats->cursz; else if (outsbsz >= sizeof(struct statsblob)) outsbsz = sizeof(struct statsblob); else error = EINVAL; INP_WUNLOCK(inp); if (error) break; sbp = sopt->sopt_val; nheld = atop(round_page(((vm_offset_t)sbp) + (vm_size_t)outsbsz) - trunc_page((vm_offset_t)sbp)); vm_page_t ma[nheld]; if (vm_fault_quick_hold_pages( &curproc->p_vmspace->vm_map, (vm_offset_t)sbp, outsbsz, VM_PROT_READ | VM_PROT_WRITE, ma, nheld) < 0) { error = EFAULT; break; } if ((error = copyin_nofault(&(sbp->flags), &sbflags, SIZEOF_MEMBER(struct statsblob, flags)))) goto unhold; INP_WLOCK_RECHECK(inp); error = stats_blob_snapshot(&sbp, outsbsz, tp->t_stats, sbflags | SB_CLONE_USRDSTNOFAULT); INP_WUNLOCK(inp); sopt->sopt_valsize = outsbsz; unhold: vm_page_unhold_pages(ma, nheld); #else INP_WUNLOCK(inp); error = EOPNOTSUPP; #endif /* !STATS */ break; } case TCP_CONGESTION: len = strlcpy(buf, CC_ALGO(tp)->name, TCP_CA_NAME_MAX); INP_WUNLOCK(inp); error = sooptcopyout(sopt, buf, len + 1); break; case TCP_MAXUNACKTIME: case TCP_KEEPIDLE: case TCP_KEEPINTVL: case TCP_KEEPINIT: case TCP_KEEPCNT: switch (sopt->sopt_name) { case TCP_MAXUNACKTIME: ui = TP_MAXUNACKTIME(tp) / hz; break; case TCP_KEEPIDLE: ui = TP_KEEPIDLE(tp) / hz; break; case TCP_KEEPINTVL: ui = TP_KEEPINTVL(tp) / hz; break; case TCP_KEEPINIT: ui = TP_KEEPINIT(tp) / hz; break; case TCP_KEEPCNT: ui = TP_KEEPCNT(tp); break; } INP_WUNLOCK(inp); error = sooptcopyout(sopt, &ui, sizeof(ui)); break; #ifdef TCPPCAP case TCP_PCAP_OUT: case TCP_PCAP_IN: optval = tcp_pcap_get_sock_max( (sopt->sopt_name == TCP_PCAP_OUT) ? &(tp->t_outpkts) : &(tp->t_inpkts)); INP_WUNLOCK(inp); error = sooptcopyout(sopt, &optval, sizeof optval); break; #endif case TCP_FASTOPEN: optval = tp->t_flags & TF_FASTOPEN; INP_WUNLOCK(inp); error = sooptcopyout(sopt, &optval, sizeof optval); break; #ifdef TCP_BLACKBOX case TCP_LOG: optval = tcp_get_bblog_state(tp); INP_WUNLOCK(inp); error = sooptcopyout(sopt, &optval, sizeof(optval)); break; case TCP_LOGBUF: /* tcp_log_getlogbuf() does INP_WUNLOCK(inp) */ error = tcp_log_getlogbuf(sopt, tp); break; case TCP_LOGID: len = tcp_log_get_id(tp, buf); INP_WUNLOCK(inp); error = sooptcopyout(sopt, buf, len + 1); break; case TCP_LOGDUMP: case TCP_LOGDUMPID: INP_WUNLOCK(inp); error = EINVAL; break; #endif #ifdef KERN_TLS case TCP_TXTLS_MODE: error = ktls_get_tx_mode(so, &optval); INP_WUNLOCK(inp); if (error == 0) error = sooptcopyout(sopt, &optval, sizeof(optval)); break; case TCP_RXTLS_MODE: error = ktls_get_rx_mode(so, &optval); INP_WUNLOCK(inp); if (error == 0) error = sooptcopyout(sopt, &optval, sizeof(optval)); break; #endif default: INP_WUNLOCK(inp); error = ENOPROTOOPT; break; } break; } return (error); } #undef INP_WLOCK_RECHECK #undef INP_WLOCK_RECHECK_CLEANUP /* * Initiate (or continue) disconnect. * If embryonic state, just send reset (once). * If in ``let data drain'' option and linger null, just drop. * Otherwise (hard), mark socket disconnecting and drop * current input data; switch states based on user close, and * send segment to peer (with FIN). */ static void tcp_disconnect(struct tcpcb *tp) { struct inpcb *inp = tptoinpcb(tp); struct socket *so = tptosocket(tp); NET_EPOCH_ASSERT(); INP_WLOCK_ASSERT(inp); /* * Neither tcp_close() nor tcp_drop() should return NULL, as the * socket is still open. */ if (tp->t_state < TCPS_ESTABLISHED && !(tp->t_state > TCPS_LISTEN && (tp->t_flags & TF_FASTOPEN))) { tp = tcp_close(tp); KASSERT(tp != NULL, ("tcp_disconnect: tcp_close() returned NULL")); } else if ((so->so_options & SO_LINGER) && so->so_linger == 0) { tp = tcp_drop(tp, 0); KASSERT(tp != NULL, ("tcp_disconnect: tcp_drop() returned NULL")); } else { soisdisconnecting(so); sbflush(&so->so_rcv); tcp_usrclosed(tp); if (!(inp->inp_flags & INP_DROPPED)) /* Ignore stack's drop request, we already at it. */ (void)tcp_output_nodrop(tp); } } /* * User issued close, and wish to trail through shutdown states: * if never received SYN, just forget it. If got a SYN from peer, * but haven't sent FIN, then go to FIN_WAIT_1 state to send peer a FIN. * If already got a FIN from peer, then almost done; go to LAST_ACK * state. In all other cases, have already sent FIN to peer (e.g. * after PRU_SHUTDOWN), and just have to play tedious game waiting * for peer to send FIN or not respond to keep-alives, etc. * We can let the user exit from the close as soon as the FIN is acked. */ static void tcp_usrclosed(struct tcpcb *tp) { NET_EPOCH_ASSERT(); INP_WLOCK_ASSERT(tptoinpcb(tp)); switch (tp->t_state) { case TCPS_LISTEN: #ifdef TCP_OFFLOAD tcp_offload_listen_stop(tp); #endif tcp_state_change(tp, TCPS_CLOSED); /* FALLTHROUGH */ case TCPS_CLOSED: tp = tcp_close(tp); /* * tcp_close() should never return NULL here as the socket is * still open. */ KASSERT(tp != NULL, ("tcp_usrclosed: tcp_close() returned NULL")); break; case TCPS_SYN_SENT: case TCPS_SYN_RECEIVED: tp->t_flags |= TF_NEEDFIN; break; case TCPS_ESTABLISHED: tcp_state_change(tp, TCPS_FIN_WAIT_1); break; case TCPS_CLOSE_WAIT: tcp_state_change(tp, TCPS_LAST_ACK); break; } if (tp->t_acktime == 0) tp->t_acktime = ticks; if (tp->t_state >= TCPS_FIN_WAIT_2) { tcp_free_sackholes(tp); soisdisconnected(tptosocket(tp)); /* Prevent the connection hanging in FIN_WAIT_2 forever. */ if (tp->t_state == TCPS_FIN_WAIT_2) { int timeout; timeout = (tcp_fast_finwait2_recycle) ? tcp_finwait2_timeout : TP_MAXIDLE(tp); tcp_timer_activate(tp, TT_2MSL, timeout); } } } #ifdef DDB static void db_print_indent(int indent) { int i; for (i = 0; i < indent; i++) db_printf(" "); } static void db_print_tstate(int t_state) { switch (t_state) { case TCPS_CLOSED: db_printf("TCPS_CLOSED"); return; case TCPS_LISTEN: db_printf("TCPS_LISTEN"); return; case TCPS_SYN_SENT: db_printf("TCPS_SYN_SENT"); return; case TCPS_SYN_RECEIVED: db_printf("TCPS_SYN_RECEIVED"); return; case TCPS_ESTABLISHED: db_printf("TCPS_ESTABLISHED"); return; case TCPS_CLOSE_WAIT: db_printf("TCPS_CLOSE_WAIT"); return; case TCPS_FIN_WAIT_1: db_printf("TCPS_FIN_WAIT_1"); return; case TCPS_CLOSING: db_printf("TCPS_CLOSING"); return; case TCPS_LAST_ACK: db_printf("TCPS_LAST_ACK"); return; case TCPS_FIN_WAIT_2: db_printf("TCPS_FIN_WAIT_2"); return; case TCPS_TIME_WAIT: db_printf("TCPS_TIME_WAIT"); return; default: db_printf("unknown"); return; } } static void db_print_tflags(u_int t_flags) { int comma; comma = 0; if (t_flags & TF_ACKNOW) { db_printf("%sTF_ACKNOW", comma ? ", " : ""); comma = 1; } if (t_flags & TF_DELACK) { db_printf("%sTF_DELACK", comma ? ", " : ""); comma = 1; } if (t_flags & TF_NODELAY) { db_printf("%sTF_NODELAY", comma ? ", " : ""); comma = 1; } if (t_flags & TF_NOOPT) { db_printf("%sTF_NOOPT", comma ? ", " : ""); comma = 1; } if (t_flags & TF_SENTFIN) { db_printf("%sTF_SENTFIN", comma ? ", " : ""); comma = 1; } if (t_flags & TF_REQ_SCALE) { db_printf("%sTF_REQ_SCALE", comma ? ", " : ""); comma = 1; } if (t_flags & TF_RCVD_SCALE) { db_printf("%sTF_RECVD_SCALE", comma ? ", " : ""); comma = 1; } if (t_flags & TF_REQ_TSTMP) { db_printf("%sTF_REQ_TSTMP", comma ? ", " : ""); comma = 1; } if (t_flags & TF_RCVD_TSTMP) { db_printf("%sTF_RCVD_TSTMP", comma ? ", " : ""); comma = 1; } if (t_flags & TF_SACK_PERMIT) { db_printf("%sTF_SACK_PERMIT", comma ? ", " : ""); comma = 1; } if (t_flags & TF_NEEDSYN) { db_printf("%sTF_NEEDSYN", comma ? ", " : ""); comma = 1; } if (t_flags & TF_NEEDFIN) { db_printf("%sTF_NEEDFIN", comma ? ", " : ""); comma = 1; } if (t_flags & TF_NOPUSH) { db_printf("%sTF_NOPUSH", comma ? ", " : ""); comma = 1; } if (t_flags & TF_PREVVALID) { db_printf("%sTF_PREVVALID", comma ? ", " : ""); comma = 1; } if (t_flags & TF_WAKESOR) { db_printf("%sTF_WAKESOR", comma ? ", " : ""); comma = 1; } if (t_flags & TF_GPUTINPROG) { db_printf("%sTF_GPUTINPROG", comma ? ", " : ""); comma = 1; } if (t_flags & TF_MORETOCOME) { db_printf("%sTF_MORETOCOME", comma ? ", " : ""); comma = 1; } if (t_flags & TF_SONOTCONN) { db_printf("%sTF_SONOTCONN", comma ? ", " : ""); comma = 1; } if (t_flags & TF_LASTIDLE) { db_printf("%sTF_LASTIDLE", comma ? ", " : ""); comma = 1; } if (t_flags & TF_RXWIN0SENT) { db_printf("%sTF_RXWIN0SENT", comma ? ", " : ""); comma = 1; } if (t_flags & TF_FASTRECOVERY) { db_printf("%sTF_FASTRECOVERY", comma ? ", " : ""); comma = 1; } if (t_flags & TF_WASFRECOVERY) { db_printf("%sTF_WASFRECOVERY", comma ? ", " : ""); comma = 1; } if (t_flags & TF_SIGNATURE) { db_printf("%sTF_SIGNATURE", comma ? ", " : ""); comma = 1; } if (t_flags & TF_FORCEDATA) { db_printf("%sTF_FORCEDATA", comma ? ", " : ""); comma = 1; } if (t_flags & TF_TSO) { db_printf("%sTF_TSO", comma ? ", " : ""); comma = 1; } if (t_flags & TF_TOE) { db_printf("%sTF_TOE", comma ? ", " : ""); comma = 1; } if (t_flags & TF_CLOSED) { db_printf("%sTF_CLOSED", comma ? ", " : ""); comma = 1; } if (t_flags & TF_SENTSYN) { db_printf("%sTF_SENTSYN", comma ? ", " : ""); comma = 1; } if (t_flags & TF_LRD) { db_printf("%sTF_LRD", comma ? ", " : ""); comma = 1; } if (t_flags & TF_CONGRECOVERY) { db_printf("%sTF_CONGRECOVERY", comma ? ", " : ""); comma = 1; } if (t_flags & TF_WASCRECOVERY) { db_printf("%sTF_WASCRECOVERY", comma ? ", " : ""); comma = 1; } if (t_flags & TF_FASTOPEN) { db_printf("%sTF_FASTOPEN", comma ? ", " : ""); comma = 1; } } static void db_print_tflags2(u_int t_flags2) { int comma; comma = 0; if (t_flags2 & TF2_PLPMTU_BLACKHOLE) { db_printf("%sTF2_PLPMTU_BLACKHOLE", comma ? ", " : ""); comma = 1; } if (t_flags2 & TF2_PLPMTU_PMTUD) { db_printf("%sTF2_PLPMTU_PMTUD", comma ? ", " : ""); comma = 1; } if (t_flags2 & TF2_PLPMTU_MAXSEGSNT) { db_printf("%sTF2_PLPMTU_MAXSEGSNT", comma ? ", " : ""); comma = 1; } if (t_flags2 & TF2_LOG_AUTO) { db_printf("%sTF2_LOG_AUTO", comma ? ", " : ""); comma = 1; } if (t_flags2 & TF2_DROP_AF_DATA) { db_printf("%sTF2_DROP_AF_DATA", comma ? ", " : ""); comma = 1; } if (t_flags2 & TF2_ECN_PERMIT) { db_printf("%sTF2_ECN_PERMIT", comma ? ", " : ""); comma = 1; } if (t_flags2 & TF2_ECN_SND_CWR) { db_printf("%sTF2_ECN_SND_CWR", comma ? ", " : ""); comma = 1; } if (t_flags2 & TF2_ECN_SND_ECE) { db_printf("%sTF2_ECN_SND_ECE", comma ? ", " : ""); comma = 1; } if (t_flags2 & TF2_ACE_PERMIT) { db_printf("%sTF2_ACE_PERMIT", comma ? ", " : ""); comma = 1; } if (t_flags2 & TF2_HPTS_CPU_SET) { db_printf("%sTF2_HPTS_CPU_SET", comma ? ", " : ""); comma = 1; } if (t_flags2 & TF2_FBYTES_COMPLETE) { db_printf("%sTF2_FBYTES_COMPLETE", comma ? ", " : ""); comma = 1; } if (t_flags2 & TF2_ECN_USE_ECT1) { db_printf("%sTF2_ECN_USE_ECT1", comma ? ", " : ""); comma = 1; } if (t_flags2 & TF2_TCP_ACCOUNTING) { db_printf("%sTF2_TCP_ACCOUNTING", comma ? ", " : ""); comma = 1; } if (t_flags2 & TF2_HPTS_CALLS) { db_printf("%sTF2_HPTS_CALLS", comma ? ", " : ""); comma = 1; } if (t_flags2 & TF2_MBUF_L_ACKS) { db_printf("%sTF2_MBUF_L_ACKS", comma ? ", " : ""); comma = 1; } if (t_flags2 & TF2_MBUF_ACKCMP) { db_printf("%sTF2_MBUF_ACKCMP", comma ? ", " : ""); comma = 1; } if (t_flags2 & TF2_SUPPORTS_MBUFQ) { db_printf("%sTF2_SUPPORTS_MBUFQ", comma ? ", " : ""); comma = 1; } if (t_flags2 & TF2_MBUF_QUEUE_READY) { db_printf("%sTF2_MBUF_QUEUE_READY", comma ? ", " : ""); comma = 1; } if (t_flags2 & TF2_DONT_SACK_QUEUE) { db_printf("%sTF2_DONT_SACK_QUEUE", comma ? ", " : ""); comma = 1; } if (t_flags2 & TF2_CANNOT_DO_ECN) { db_printf("%sTF2_CANNOT_DO_ECN", comma ? ", " : ""); comma = 1; } if (t_flags2 & TF2_PROC_SACK_PROHIBIT) { db_printf("%sTF2_PROC_SACK_PROHIBIT", comma ? ", " : ""); comma = 1; } if (t_flags2 & TF2_IPSEC_TSO) { db_printf("%sTF2_IPSEC_TSO", comma ? ", " : ""); comma = 1; } if (t_flags2 & TF2_NO_ISS_CHECK) { db_printf("%sTF2_NO_ISS_CHECK", comma ? ", " : ""); comma = 1; } } static void db_print_toobflags(char t_oobflags) { int comma; comma = 0; if (t_oobflags & TCPOOB_HAVEDATA) { db_printf("%sTCPOOB_HAVEDATA", comma ? ", " : ""); comma = 1; } if (t_oobflags & TCPOOB_HADDATA) { db_printf("%sTCPOOB_HADDATA", comma ? ", " : ""); comma = 1; } } static void db_print_tcpcb(struct tcpcb *tp, const char *name, int indent) { db_print_indent(indent); db_printf("%s at %p\n", name, tp); indent += 2; db_print_indent(indent); db_printf("t_segq first: %p t_segqlen: %d t_dupacks: %d\n", TAILQ_FIRST(&tp->t_segq), tp->t_segqlen, tp->t_dupacks); db_print_indent(indent); db_printf("t_callout: %p t_timers: %p\n", &tp->t_callout, &tp->t_timers); db_print_indent(indent); db_printf("t_state: %d (", tp->t_state); db_print_tstate(tp->t_state); db_printf(")\n"); db_print_indent(indent); db_printf("t_flags: 0x%x (", tp->t_flags); db_print_tflags(tp->t_flags); db_printf(")\n"); db_print_indent(indent); db_printf("t_flags2: 0x%x (", tp->t_flags2); db_print_tflags2(tp->t_flags2); db_printf(")\n"); db_print_indent(indent); db_printf("snd_una: 0x%08x snd_max: 0x%08x snd_nxt: 0x%08x\n", tp->snd_una, tp->snd_max, tp->snd_nxt); db_print_indent(indent); db_printf("snd_up: 0x%08x snd_wl1: 0x%08x snd_wl2: 0x%08x\n", tp->snd_up, tp->snd_wl1, tp->snd_wl2); db_print_indent(indent); db_printf("iss: 0x%08x irs: 0x%08x rcv_nxt: 0x%08x\n", tp->iss, tp->irs, tp->rcv_nxt); db_print_indent(indent); db_printf("rcv_adv: 0x%08x rcv_wnd: %u rcv_up: 0x%08x\n", tp->rcv_adv, tp->rcv_wnd, tp->rcv_up); db_print_indent(indent); db_printf("snd_wnd: %u snd_cwnd: %u\n", tp->snd_wnd, tp->snd_cwnd); db_print_indent(indent); db_printf("snd_ssthresh: %u snd_recover: " "0x%08x\n", tp->snd_ssthresh, tp->snd_recover); db_print_indent(indent); db_printf("t_rcvtime: %u t_startime: %u\n", tp->t_rcvtime, tp->t_starttime); db_print_indent(indent); db_printf("t_rttime: %u t_rtsq: 0x%08x\n", tp->t_rtttime, tp->t_rtseq); db_print_indent(indent); db_printf("t_rxtcur: %d t_maxseg: %u t_srtt: %d\n", tp->t_rxtcur, tp->t_maxseg, tp->t_srtt); db_print_indent(indent); db_printf("t_rttvar: %d t_rxtshift: %d t_rttmin: %u\n", tp->t_rttvar, tp->t_rxtshift, tp->t_rttmin); db_print_indent(indent); db_printf("t_rttupdated: %u max_sndwnd: %u t_softerror: %d\n", tp->t_rttupdated, tp->max_sndwnd, tp->t_softerror); db_print_indent(indent); db_printf("t_oobflags: 0x%x (", tp->t_oobflags); db_print_toobflags(tp->t_oobflags); db_printf(") t_iobc: 0x%02x\n", tp->t_iobc); db_print_indent(indent); db_printf("snd_scale: %u rcv_scale: %u request_r_scale: %u\n", tp->snd_scale, tp->rcv_scale, tp->request_r_scale); db_print_indent(indent); db_printf("ts_recent: %u ts_recent_age: %u\n", tp->ts_recent, tp->ts_recent_age); db_print_indent(indent); db_printf("ts_offset: %u last_ack_sent: 0x%08x snd_cwnd_prev: " "%u\n", tp->ts_offset, tp->last_ack_sent, tp->snd_cwnd_prev); db_print_indent(indent); db_printf("snd_ssthresh_prev: %u snd_recover_prev: 0x%08x " "t_badrxtwin: %u\n", tp->snd_ssthresh_prev, tp->snd_recover_prev, tp->t_badrxtwin); db_print_indent(indent); db_printf("snd_numholes: %d snd_holes first: %p\n", tp->snd_numholes, TAILQ_FIRST(&tp->snd_holes)); db_print_indent(indent); db_printf("snd_fack: 0x%08x rcv_numsacks: %d\n", tp->snd_fack, tp->rcv_numsacks); /* Skip sackblks, sackhint. */ db_print_indent(indent); db_printf("t_rttlow: %d rfbuf_ts: %u rfbuf_cnt: %d\n", tp->t_rttlow, tp->rfbuf_ts, tp->rfbuf_cnt); } DB_SHOW_COMMAND(tcpcb, db_show_tcpcb) { struct tcpcb *tp; if (!have_addr) { db_printf("usage: show tcpcb \n"); return; } tp = (struct tcpcb *)addr; db_print_tcpcb(tp, "tcpcb", 0); } #endif