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Differential D4350 Diff 11670 head/sys/netinet/tcp_input.c

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head/sys/netinet/tcp_input.c

Show First 20 Lines • Show All 92 Lines • ▼ Show 20 Lines
#include <netinet/icmp_var.h> /* for ICMP_BANDLIM */ #include <netinet/icmp_var.h> /* for ICMP_BANDLIM */
#include <netinet/ip_var.h> #include <netinet/ip_var.h>
#include <netinet/ip_options.h> #include <netinet/ip_options.h>
#include <netinet/ip6.h> #include <netinet/ip6.h>
#include <netinet/icmp6.h> #include <netinet/icmp6.h>
#include <netinet6/in6_pcb.h> #include <netinet6/in6_pcb.h>
#include <netinet6/ip6_var.h> #include <netinet6/ip6_var.h>
#include <netinet6/nd6.h> #include <netinet6/nd6.h>
#ifdef TCP_RFC7413
#include <netinet/tcp_fastopen.h>
#endif
#include <netinet/tcp_fsm.h> #include <netinet/tcp_fsm.h>
#include <netinet/tcp_seq.h> #include <netinet/tcp_seq.h>
#include <netinet/tcp_timer.h> #include <netinet/tcp_timer.h>
#include <netinet/tcp_var.h> #include <netinet/tcp_var.h>
#include <netinet6/tcp6_var.h> #include <netinet6/tcp6_var.h>
#include <netinet/tcpip.h> #include <netinet/tcpip.h>
#ifdef TCPPCAP #ifdef TCPPCAP
#include <netinet/tcp_pcap.h> #include <netinet/tcp_pcap.h>
▲ Show 20 Lines • Show All 885 Lines • ▼ Show 20 Lines#endif
* relock, we have to jump back to 'relocked' as the connection might * relock, we have to jump back to 'relocked' as the connection might
* now be in TIMEWAIT. * now be in TIMEWAIT.
*/ */
#ifdef INVARIANTS #ifdef INVARIANTS
if ((thflags & (TH_FIN | TH_RST)) != 0) if ((thflags & (TH_FIN | TH_RST)) != 0)
INP_INFO_RLOCK_ASSERT(&V_tcbinfo); INP_INFO_RLOCK_ASSERT(&V_tcbinfo);
#endif #endif
if (!((tp->t_state == TCPS_ESTABLISHED && (thflags & TH_SYN) == 0) || if (!((tp->t_state == TCPS_ESTABLISHED && (thflags & TH_SYN) == 0) ||
(tp->t_state == TCPS_LISTEN && (thflags & TH_SYN)))) { (tp->t_state == TCPS_LISTEN && (thflags & TH_SYN) &&
!(tp->t_flags & TF_FASTOPEN)))) {
if (ti_locked == TI_UNLOCKED) { if (ti_locked == TI_UNLOCKED) {
if (INP_INFO_TRY_RLOCK(&V_tcbinfo) == 0) { if (INP_INFO_TRY_RLOCK(&V_tcbinfo) == 0) {
in_pcbref(inp); in_pcbref(inp);
INP_WUNLOCK(inp); INP_WUNLOCK(inp);
INP_INFO_RLOCK(&V_tcbinfo); INP_INFO_RLOCK(&V_tcbinfo);
ti_locked = TI_RLOCKED; ti_locked = TI_RLOCKED;
INP_WLOCK(inp); INP_WLOCK(inp);
if (in_pcbrele_wlocked(inp)) { if (in_pcbrele_wlocked(inp)) {
▲ Show 20 Lines • Show All 75 Lines • ▼ Show 20 Lines if ((thflags & (TH_RST|TH_ACK|TH_SYN)) == TH_ACK) {
* No syncache entry or ACK was not * No syncache entry or ACK was not
* for our SYN/ACK. Send a RST. * for our SYN/ACK. Send a RST.
* NB: syncache did its own logging * NB: syncache did its own logging
* of the failure cause. * of the failure cause.
*/ */
rstreason = BANDLIM_RST_OPENPORT; rstreason = BANDLIM_RST_OPENPORT;
goto dropwithreset; goto dropwithreset;
} }
#ifdef TCP_RFC7413
new_tfo_socket:
#endif
if (so == NULL) { if (so == NULL) {
/* /*
* We completed the 3-way handshake * We completed the 3-way handshake
* but could not allocate a socket * but could not allocate a socket
* either due to memory shortage, * either due to memory shortage,
* listen queue length limits or * listen queue length limits or
* global socket limits. Send RST * global socket limits. Send RST
* or wait and have the remote end * or wait and have the remote end
▲ Show 20 Lines • Show All 246 Lines • ▼ Show 20 Lines#endif
*/ */
#ifdef TCPDEBUG #ifdef TCPDEBUG
if (so->so_options & SO_DEBUG) if (so->so_options & SO_DEBUG)
tcp_trace(TA_INPUT, ostate, tp, tcp_trace(TA_INPUT, ostate, tp,
(void *)tcp_saveipgen, &tcp_savetcp, 0); (void *)tcp_saveipgen, &tcp_savetcp, 0);
#endif #endif
TCP_PROBE3(debug__input, tp, th, mtod(m, const char *)); TCP_PROBE3(debug__input, tp, th, mtod(m, const char *));
tcp_dooptions(&to, optp, optlen, TO_SYN); tcp_dooptions(&to, optp, optlen, TO_SYN);
#ifdef TCP_RFC7413
if (syncache_add(&inc, &to, th, inp, &so, m, NULL, NULL))
goto new_tfo_socket;
#else
syncache_add(&inc, &to, th, inp, &so, m, NULL, NULL); syncache_add(&inc, &to, th, inp, &so, m, NULL, NULL);
#endif
/* /*
* Entry added to syncache and mbuf consumed. * Entry added to syncache and mbuf consumed.
* Only the listen socket is unlocked by syncache_add(). * Only the listen socket is unlocked by syncache_add().
*/ */
if (ti_locked == TI_RLOCKED) { if (ti_locked == TI_RLOCKED) {
INP_INFO_RUNLOCK(&V_tcbinfo); INP_INFO_RUNLOCK(&V_tcbinfo);
ti_locked = TI_UNLOCKED; ti_locked = TI_UNLOCKED;
} }
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{ {
int thflags, acked, ourfinisacked, needoutput = 0, sack_changed; int thflags, acked, ourfinisacked, needoutput = 0, sack_changed;
int rstreason, todrop, win; int rstreason, todrop, win;
u_long tiwin; u_long tiwin;
char *s; char *s;
struct in_conninfo *inc; struct in_conninfo *inc;
struct mbuf *mfree; struct mbuf *mfree;
struct tcpopt to; struct tcpopt to;
int tfo_syn;
#ifdef TCPDEBUG #ifdef TCPDEBUG
/* /*
* The size of tcp_saveipgen must be the size of the max ip header, * The size of tcp_saveipgen must be the size of the max ip header,
* now IPv6. * now IPv6.
*/ */
u_char tcp_saveipgen[IP6_HDR_LEN]; u_char tcp_saveipgen[IP6_HDR_LEN];
struct tcphdr tcp_savetcp; struct tcphdr tcp_savetcp;
short ostate = 0; short ostate = 0;
▲ Show 20 Lines • Show All 436 Lines • ▼ Show 20 Lines#endif
*/ */
case TCPS_SYN_RECEIVED: case TCPS_SYN_RECEIVED:
if ((thflags & TH_ACK) && if ((thflags & TH_ACK) &&
(SEQ_LEQ(th->th_ack, tp->snd_una) || (SEQ_LEQ(th->th_ack, tp->snd_una) ||
SEQ_GT(th->th_ack, tp->snd_max))) { SEQ_GT(th->th_ack, tp->snd_max))) {
rstreason = BANDLIM_RST_OPENPORT; rstreason = BANDLIM_RST_OPENPORT;
goto dropwithreset; goto dropwithreset;
} }
#ifdef TCP_RFC7413
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;
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;
}
}
#endif
break; break;
/* /*
* If the state is SYN_SENT: * If the state is SYN_SENT:
* if seg contains an ACK, but not for our SYN, drop the input. * if seg contains an ACK, but not for our SYN, drop the input.
* if seg contains a RST, then drop the connection. * if seg contains a RST, then drop the connection.
* if seg does not contain SYN, then drop it. * if seg does not contain SYN, then drop it.
* Otherwise this is an acceptable SYN segment * Otherwise this is an acceptable SYN segment
▲ Show 20 Lines • Show All 199 Lines • ▼ Show 20 Lines if (thflags & TH_RST) {
} }
goto drop; goto drop;
} }
/* /*
* RFC5961 Section 4.2 * RFC5961 Section 4.2
* Send challenge ACK for any SYN in synchronized state. * Send challenge ACK for any SYN in synchronized state.
*/ */
if ((thflags & TH_SYN) && tp->t_state != TCPS_SYN_SENT) { if ((thflags & TH_SYN) && tp->t_state != TCPS_SYN_SENT &&
tp->t_state != TCPS_SYN_RECEIVED) {
KASSERT(ti_locked == TI_RLOCKED, KASSERT(ti_locked == TI_RLOCKED,
("tcp_do_segment: TH_SYN ti_locked %d", ti_locked)); ("tcp_do_segment: TH_SYN ti_locked %d", ti_locked));
INP_INFO_RLOCK_ASSERT(&V_tcbinfo); INP_INFO_RLOCK_ASSERT(&V_tcbinfo);
TCPSTAT_INC(tcps_badsyn); TCPSTAT_INC(tcps_badsyn);
if (V_tcp_insecure_syn && if (V_tcp_insecure_syn &&
SEQ_GEQ(th->th_seq, tp->last_ack_sent) && SEQ_GEQ(th->th_seq, tp->last_ack_sent) &&
SEQ_LT(th->th_seq, tp->last_ack_sent + tp->rcv_wnd)) { SEQ_LT(th->th_seq, tp->last_ack_sent + tp->rcv_wnd)) {
▲ Show 20 Lines • Show All 177 Lines • ▼ Show 20 Lines#endif
/* /*
* If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN * If the ACK bit is off: if in SYN-RECEIVED state or SENDSYN
* flag is on (half-synchronized state), then queue data for * flag is on (half-synchronized state), then queue data for
* later processing; else drop segment and return. * later processing; else drop segment and return.
*/ */
if ((thflags & TH_ACK) == 0) { if ((thflags & TH_ACK) == 0) {
if (tp->t_state == TCPS_SYN_RECEIVED || if (tp->t_state == TCPS_SYN_RECEIVED ||
(tp->t_flags & TF_NEEDSYN)) (tp->t_flags & TF_NEEDSYN)) {
#ifdef TCP_RFC7413
if (tp->t_state == TCPS_SYN_RECEIVED &&
tp->t_flags & TF_FASTOPEN) {
tp->snd_wnd = tiwin;
cc_conn_init(tp);
}
#endif
goto step6; goto step6;
else if (tp->t_flags & TF_ACKNOW) } else if (tp->t_flags & TF_ACKNOW)
goto dropafterack; goto dropafterack;
else else
goto drop; goto drop;
} }
/* /*
* Ack processing. * Ack processing.
*/ */
Show All 22 Lines case TCPS_SYN_RECEIVED:
tp->t_starttime = ticks; tp->t_starttime = ticks;
if (tp->t_flags & TF_NEEDFIN) { if (tp->t_flags & TF_NEEDFIN) {
tcp_state_change(tp, TCPS_FIN_WAIT_1); tcp_state_change(tp, TCPS_FIN_WAIT_1);
tp->t_flags &= ~TF_NEEDFIN; tp->t_flags &= ~TF_NEEDFIN;
} else { } else {
tcp_state_change(tp, TCPS_ESTABLISHED); tcp_state_change(tp, TCPS_ESTABLISHED);
TCP_PROBE5(accept__established, NULL, tp, TCP_PROBE5(accept__established, NULL, tp,
mtod(m, const char *), tp, th); mtod(m, const char *), tp, th);
#ifdef TCP_RFC7413
if (tp->t_tfo_pending) {
tcp_fastopen_decrement_counter(tp->t_tfo_pending);
tp->t_tfo_pending = NULL;
/*
* Account for the ACK of our SYN prior to
* regular ACK processing below.
*/
tp->snd_una++;
}
/*
* 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))
#endif
cc_conn_init(tp); cc_conn_init(tp);
tcp_timer_activate(tp, TT_KEEP, TP_KEEPIDLE(tp)); tcp_timer_activate(tp, TT_KEEP, TP_KEEPIDLE(tp));
} }
/* /*
* If segment contains data or ACK, will call tcp_reass() * If segment contains data or ACK, will call tcp_reass()
* later; if not, do so now to pass queued data to user. * later; if not, do so now to pass queued data to user.
*/ */
if (tlen == 0 && (thflags & TH_FIN) == 0) if (tlen == 0 && (thflags & TH_FIN) == 0)
(void) tcp_reass(tp, (struct tcphdr *)0, 0, (void) tcp_reass(tp, (struct tcphdr *)0, 0,
▲ Show 20 Lines • Show All 531 Lines • ▼ Show 20 Linesdodata: /* XXX */
/* /*
* Process the segment text, merging it into the TCP sequencing queue, * Process the segment text, merging it into the TCP sequencing queue,
* and arranging for acknowledgment of receipt if necessary. * and arranging for acknowledgment of receipt if necessary.
* This process logically involves adjusting tp->rcv_wnd as data * This process logically involves adjusting tp->rcv_wnd as data
* is presented to the user (this happens in tcp_usrreq.c, * is presented to the user (this happens in tcp_usrreq.c,
* case PRU_RCVD). If a FIN has already been received on this * case PRU_RCVD). If a FIN has already been received on this
* connection then we just ignore the text. * connection then we just ignore the text.
*/ */
if ((tlen || (thflags & TH_FIN)) && tfo_syn = ((tp->t_state == TCPS_SYN_RECEIVED) &&
(tp->t_flags & TF_FASTOPEN));
if ((tlen || (thflags & TH_FIN) || tfo_syn) &&
TCPS_HAVERCVDFIN(tp->t_state) == 0) { TCPS_HAVERCVDFIN(tp->t_state) == 0) {
tcp_seq save_start = th->th_seq; tcp_seq save_start = th->th_seq;
m_adj(m, drop_hdrlen); /* delayed header drop */ m_adj(m, drop_hdrlen); /* delayed header drop */
/* /*
* Insert segment which includes th into TCP reassembly queue * Insert segment which includes th into TCP reassembly queue
* with control block tp. Set thflags to whether reassembly now * with control block tp. Set thflags to whether reassembly now
* includes a segment with FIN. This handles the common case * includes a segment with FIN. This handles the common case
* inline (segment is the next to be received on an established * inline (segment is the next to be received on an established
* connection, and the queue is empty), avoiding linkage into * connection, and the queue is empty), avoiding linkage into
* and removal from the queue and repetition of various * and removal from the queue and repetition of various
* conversions. * conversions.
* Set DELACK for segments received in order, but ack * Set DELACK for segments received in order, but ack
* immediately when segments are out of order (so * immediately when segments are out of order (so
* fast retransmit can work). * fast retransmit can work).
*/ */
if (th->th_seq == tp->rcv_nxt && if (th->th_seq == tp->rcv_nxt &&
LIST_EMPTY(&tp->t_segq) && LIST_EMPTY(&tp->t_segq) &&
TCPS_HAVEESTABLISHED(tp->t_state)) { (TCPS_HAVEESTABLISHED(tp->t_state) ||
if (DELAY_ACK(tp, tlen)) tfo_syn)) {
if (DELAY_ACK(tp, tlen) || tfo_syn)
tp->t_flags |= TF_DELACK; tp->t_flags |= TF_DELACK;
else else
tp->t_flags |= TF_ACKNOW; tp->t_flags |= TF_ACKNOW;
tp->rcv_nxt += tlen; tp->rcv_nxt += tlen;
thflags = th->th_flags & TH_FIN; thflags = th->th_flags & TH_FIN;
TCPSTAT_INC(tcps_rcvpack); TCPSTAT_INC(tcps_rcvpack);
TCPSTAT_ADD(tcps_rcvbyte, tlen); TCPSTAT_ADD(tcps_rcvbyte, tlen);
SOCKBUF_LOCK(&so->so_rcv); SOCKBUF_LOCK(&so->so_rcv);
▲ Show 20 Lines • Show All 338 Lines • ▼ Show 20 Lines case TCPOPT_SACK:
continue; continue;
if (flags & TO_SYN) if (flags & TO_SYN)
continue; continue;
to->to_flags |= TOF_SACK; to->to_flags |= TOF_SACK;
to->to_nsacks = (optlen - 2) / TCPOLEN_SACK; to->to_nsacks = (optlen - 2) / TCPOLEN_SACK;
to->to_sacks = cp + 2; to->to_sacks = cp + 2;
TCPSTAT_INC(tcps_sack_rcv_blocks); TCPSTAT_INC(tcps_sack_rcv_blocks);
break; break;
#ifdef TCP_RFC7413
case TCPOPT_FAST_OPEN:
if ((optlen != TCPOLEN_FAST_OPEN_EMPTY) &&
(optlen < TCPOLEN_FAST_OPEN_MIN) &&
(optlen > TCPOLEN_FAST_OPEN_MAX))
continue;
if (!(flags & TO_SYN))
continue;
if (!V_tcp_fastopen_enabled)
continue;
to->to_flags |= TOF_FASTOPEN;
to->to_tfo_len = optlen - 2;
to->to_tfo_cookie = to->to_tfo_len ? cp + 2 : NULL;
break;
#endif
default: default:
continue; continue;
} }
} }
} }
/* /*
* Pull out of band byte out of a segment so * Pull out of band byte out of a segment so
▲ Show 20 Lines • Show All 456 Lines • Show Last 20 Lines