diff --git a/sys/netinet/tcp_lro_hpts.c b/sys/netinet/tcp_lro_hpts.c
index 7724e727d5ce..84944c8db1ce 100644
--- a/sys/netinet/tcp_lro_hpts.c
+++ b/sys/netinet/tcp_lro_hpts.c
@@ -1,592 +1,593 @@
/*-
* Copyright (c) 2016-2018 Netflix, Inc.
* Copyright (c) 2016-2021 Mellanox Technologies.
*
* 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.
*
* 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 <sys/cdefs.h>
#include "opt_inet.h"
#include "opt_inet6.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sysctl.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/ethernet.h>
#include <net/bpf.h>
#include <net/vnet.h>
#include <net/if_dl.h>
#include <net/if_media.h>
#include <net/if_types.h>
#include <net/infiniband.h>
#include <net/if_lagg.h>
#include <netinet/in.h>
#include <netinet/ip6.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/in_pcb.h>
#include <netinet6/in6_pcb.h>
#include <netinet/tcp.h>
#include <netinet/tcp_lro.h>
#include <netinet/tcp_var.h>
#include <netinet/tcp_hpts.h>
#include <netinet/tcp_log_buf.h>
static void
build_ack_entry(struct tcp_ackent *ae, struct tcphdr *th, struct mbuf *m,
uint32_t *ts_ptr, uint16_t iptos)
{
/*
* Given a TCP ACK, summarize it down into the small TCP ACK
* entry.
*/
ae->timestamp = m->m_pkthdr.rcv_tstmp;
ae->flags = 0;
if (m->m_flags & M_TSTMP_LRO)
ae->flags |= TSTMP_LRO;
else if (m->m_flags & M_TSTMP)
ae->flags |= TSTMP_HDWR;
- ae->seq = ntohl(th->th_seq);
- ae->ack = ntohl(th->th_ack);
+ ae->seq = th->th_seq;
+ ae->ack = th->th_ack;
ae->flags |= tcp_get_flags(th);
if (ts_ptr != NULL) {
ae->ts_value = ntohl(ts_ptr[1]);
ae->ts_echo = ntohl(ts_ptr[2]);
ae->flags |= HAS_TSTMP;
}
- ae->win = ntohs(th->th_win);
+ ae->win = th->th_win;
ae->codepoint = iptos;
}
static inline bool
tcp_lro_ack_valid(struct mbuf *m, struct tcphdr *th, uint32_t **ppts, bool *other_opts)
{
/*
* This function returns two bits of valuable information.
* a) Is what is present capable of being ack-compressed,
* we can ack-compress if there is no options or just
* a timestamp option, and of course the th_flags must
* be correct as well.
* b) Our other options present such as SACK. This is
* used to determine if we want to wakeup or not.
*/
bool ret = true;
switch (th->th_off << 2) {
case (sizeof(*th) + TCPOLEN_TSTAMP_APPA):
*ppts = (uint32_t *)(th + 1);
/* Check if we have only one timestamp option. */
if (**ppts == TCP_LRO_TS_OPTION)
*other_opts = false;
else {
*other_opts = true;
ret = false;
}
break;
case (sizeof(*th)):
/* No options. */
*ppts = NULL;
*other_opts = false;
break;
default:
*ppts = NULL;
*other_opts = true;
ret = false;
break;
}
/* For ACKCMP we only accept ACK, PUSH, ECE and CWR. */
if ((tcp_get_flags(th) & ~(TH_ACK | TH_PUSH | TH_ECE | TH_CWR)) != 0)
ret = false;
/* If it has data on it we cannot compress it */
if (m->m_pkthdr.lro_tcp_d_len)
ret = false;
/* ACK flag must be set. */
if (!(tcp_get_flags(th) & TH_ACK))
ret = false;
return (ret);
}
static bool
tcp_lro_check_wake_status(struct tcpcb *tp)
{
if (tp->t_fb->tfb_early_wake_check != NULL)
return ((tp->t_fb->tfb_early_wake_check)(tp));
return (false);
}
static void
tcp_lro_log(struct tcpcb *tp, const struct lro_ctrl *lc,
const struct lro_entry *le, const struct mbuf *m,
int frm, int32_t tcp_data_len, uint32_t th_seq,
uint32_t th_ack, uint16_t th_win)
{
if (tcp_bblogging_on(tp)) {
union tcp_log_stackspecific log;
struct timeval tv, btv;
uint32_t cts;
cts = tcp_get_usecs(&tv);
memset(&log, 0, sizeof(union tcp_log_stackspecific));
log.u_bbr.flex8 = frm;
log.u_bbr.flex1 = tcp_data_len;
if (m)
log.u_bbr.flex2 = m->m_pkthdr.len;
else
log.u_bbr.flex2 = 0;
if (le->m_head) {
log.u_bbr.flex3 = le->m_head->m_pkthdr.lro_nsegs;
log.u_bbr.flex4 = le->m_head->m_pkthdr.lro_tcp_d_len;
log.u_bbr.flex5 = le->m_head->m_pkthdr.len;
log.u_bbr.delRate = le->m_head->m_flags;
log.u_bbr.rttProp = le->m_head->m_pkthdr.rcv_tstmp;
}
log.u_bbr.inflight = th_seq;
log.u_bbr.delivered = th_ack;
log.u_bbr.timeStamp = cts;
log.u_bbr.epoch = le->next_seq;
log.u_bbr.lt_epoch = le->ack_seq;
log.u_bbr.pacing_gain = th_win;
log.u_bbr.cwnd_gain = le->window;
log.u_bbr.lost = curcpu;
log.u_bbr.cur_del_rate = (uintptr_t)m;
log.u_bbr.bw_inuse = (uintptr_t)le->m_head;
bintime2timeval(&lc->lro_last_queue_time, &btv);
log.u_bbr.flex6 = tcp_tv_to_usectick(&btv);
log.u_bbr.flex7 = le->compressed;
log.u_bbr.pacing_gain = le->uncompressed;
if (in_epoch(net_epoch_preempt))
log.u_bbr.inhpts = 1;
else
log.u_bbr.inhpts = 0;
TCP_LOG_EVENTP(tp, NULL, &tptosocket(tp)->so_rcv,
&tptosocket(tp)->so_snd,
TCP_LOG_LRO, 0, 0, &log, false, &tv);
}
}
static struct mbuf *
tcp_lro_get_last_if_ackcmp(struct lro_ctrl *lc, struct lro_entry *le,
struct tcpcb *tp, int32_t *new_m, bool can_append_old_cmp)
{
struct mbuf *m;
/* Look at the last mbuf if any in queue */
if (can_append_old_cmp) {
m = STAILQ_LAST(&tp->t_inqueue, mbuf, m_stailqpkt);
if (m != NULL && (m->m_flags & M_ACKCMP) != 0) {
if (M_TRAILINGSPACE(m) >= sizeof(struct tcp_ackent)) {
tcp_lro_log(tp, lc, le, NULL, 23, 0, 0, 0, 0);
*new_m = 0;
counter_u64_add(tcp_extra_mbuf, 1);
return (m);
} else {
/* Mark we ran out of space */
tp->t_flags2 |= TF2_MBUF_L_ACKS;
}
}
}
/* Decide mbuf size. */
tcp_lro_log(tp, lc, le, NULL, 21, 0, 0, 0, 0);
if (tp->t_flags2 & TF2_MBUF_L_ACKS)
m = m_getcl(M_NOWAIT, MT_DATA, M_ACKCMP | M_PKTHDR);
else
m = m_gethdr(M_NOWAIT, MT_DATA);
if (__predict_false(m == NULL)) {
counter_u64_add(tcp_would_have_but, 1);
return (NULL);
}
counter_u64_add(tcp_comp_total, 1);
m->m_pkthdr.rcvif = lc->ifp;
m->m_flags |= M_ACKCMP;
*new_m = 1;
return (m);
}
/*
* Do BPF tap for either ACK_CMP packets or MBUF QUEUE type packets
* and strip all, but the IPv4/IPv6 header.
*/
static bool
do_bpf_strip_and_compress(struct tcpcb *tp, struct lro_ctrl *lc,
struct lro_entry *le, struct mbuf **pp, struct mbuf **cmp,
struct mbuf **mv_to, bool *should_wake, bool bpf_req, bool lagg_bpf_req,
struct ifnet *lagg_ifp, bool can_append_old_cmp)
{
union {
void *ptr;
struct ip *ip4;
struct ip6_hdr *ip6;
} l3;
struct mbuf *m;
struct mbuf *nm;
struct tcphdr *th;
struct tcp_ackent *ack_ent;
uint32_t *ts_ptr;
int32_t n_mbuf;
bool other_opts, can_compress;
uint8_t lro_type;
uint16_t iptos;
int tcp_hdr_offset;
int idx;
/* Get current mbuf. */
m = *pp;
/* Let the BPF see the packet */
if (__predict_false(bpf_req))
ETHER_BPF_MTAP(lc->ifp, m);
if (__predict_false(lagg_bpf_req))
ETHER_BPF_MTAP(lagg_ifp, m);
tcp_hdr_offset = m->m_pkthdr.lro_tcp_h_off;
lro_type = le->inner.data.lro_type;
switch (lro_type) {
case LRO_TYPE_NONE:
lro_type = le->outer.data.lro_type;
switch (lro_type) {
case LRO_TYPE_IPV4_TCP:
tcp_hdr_offset -= sizeof(*le->outer.ip4);
m->m_pkthdr.lro_etype = ETHERTYPE_IP;
break;
case LRO_TYPE_IPV6_TCP:
tcp_hdr_offset -= sizeof(*le->outer.ip6);
m->m_pkthdr.lro_etype = ETHERTYPE_IPV6;
break;
default:
goto compressed;
}
break;
case LRO_TYPE_IPV4_TCP:
tcp_hdr_offset -= sizeof(*le->outer.ip4);
m->m_pkthdr.lro_etype = ETHERTYPE_IP;
break;
case LRO_TYPE_IPV6_TCP:
tcp_hdr_offset -= sizeof(*le->outer.ip6);
m->m_pkthdr.lro_etype = ETHERTYPE_IPV6;
break;
default:
goto compressed;
}
MPASS(tcp_hdr_offset >= 0);
m_adj(m, tcp_hdr_offset);
m->m_flags |= M_LRO_EHDRSTRP;
m->m_flags &= ~M_ACKCMP;
m->m_pkthdr.lro_tcp_h_off -= tcp_hdr_offset;
th = tcp_lro_get_th(m);
th->th_sum = 0; /* TCP checksum is valid. */
+ tcp_fields_to_host(th);
/* Check if ACK can be compressed */
can_compress = tcp_lro_ack_valid(m, th, &ts_ptr, &other_opts);
/* Now lets look at the should wake states */
if ((other_opts == true) &&
((tp->t_flags2 & TF2_DONT_SACK_QUEUE) == 0)) {
/*
* If there are other options (SACK?) and the
* tcp endpoint has not expressly told us it does
* not care about SACKS, then we should wake up.
*/
*should_wake = true;
} else if (*should_wake == false) {
/* Wakeup override check if we are false here */
*should_wake = tcp_lro_check_wake_status(tp);
}
/* Is the ack compressable? */
if (can_compress == false)
goto done;
/* Does the TCP endpoint support ACK compression? */
if ((tp->t_flags2 & TF2_MBUF_ACKCMP) == 0)
goto done;
/* Lets get the TOS/traffic class field */
l3.ptr = mtod(m, void *);
switch (lro_type) {
case LRO_TYPE_IPV4_TCP:
iptos = l3.ip4->ip_tos;
break;
case LRO_TYPE_IPV6_TCP:
iptos = IPV6_TRAFFIC_CLASS(l3.ip6);
break;
default:
iptos = 0; /* Keep compiler happy. */
break;
}
/* Now lets get space if we don't have some already */
if (*cmp == NULL) {
new_one:
nm = tcp_lro_get_last_if_ackcmp(lc, le, tp, &n_mbuf,
can_append_old_cmp);
if (__predict_false(nm == NULL))
goto done;
*cmp = nm;
if (n_mbuf) {
/*
* Link in the new cmp ack to our in-order place,
* first set our cmp ack's next to where we are.
*/
nm->m_nextpkt = m;
(*pp) = nm;
/*
* Set it up so mv_to is advanced to our
* compressed ack. This way the caller can
* advance pp to the right place.
*/
*mv_to = nm;
/*
* Advance it here locally as well.
*/
pp = &nm->m_nextpkt;
}
} else {
/* We have one already we are working on */
nm = *cmp;
if (M_TRAILINGSPACE(nm) < sizeof(struct tcp_ackent)) {
/* We ran out of space */
tp->t_flags2 |= TF2_MBUF_L_ACKS;
goto new_one;
}
}
MPASS(M_TRAILINGSPACE(nm) >= sizeof(struct tcp_ackent));
counter_u64_add(tcp_inp_lro_compressed, 1);
le->compressed++;
/* We can add in to the one on the tail */
ack_ent = mtod(nm, struct tcp_ackent *);
idx = (nm->m_len / sizeof(struct tcp_ackent));
build_ack_entry(&ack_ent[idx], th, m, ts_ptr, iptos);
/* Bump the size of both pkt-hdr and len */
nm->m_len += sizeof(struct tcp_ackent);
nm->m_pkthdr.len += sizeof(struct tcp_ackent);
compressed:
/* Advance to next mbuf before freeing. */
*pp = m->m_nextpkt;
m->m_nextpkt = NULL;
m_freem(m);
return (true);
done:
counter_u64_add(tcp_uncomp_total, 1);
le->uncompressed++;
return (false);
}
static void
tcp_queue_pkts(struct tcpcb *tp, struct lro_entry *le)
{
INP_WLOCK_ASSERT(tptoinpcb(tp));
STAILQ_HEAD(, mbuf) q = { le->m_head,
&STAILQ_NEXT(le->m_last_mbuf, m_stailqpkt) };
STAILQ_CONCAT(&tp->t_inqueue, &q);
le->m_head = NULL;
le->m_last_mbuf = NULL;
}
static struct tcpcb *
tcp_lro_lookup(struct ifnet *ifp, struct lro_parser *pa)
{
struct inpcb *inp;
CURVNET_SET(ifp->if_vnet);
switch (pa->data.lro_type) {
#ifdef INET6
case LRO_TYPE_IPV6_TCP:
inp = in6_pcblookup(&V_tcbinfo,
&pa->data.s_addr.v6,
pa->data.s_port,
&pa->data.d_addr.v6,
pa->data.d_port,
INPLOOKUP_WLOCKPCB,
ifp);
break;
#endif
#ifdef INET
case LRO_TYPE_IPV4_TCP:
inp = in_pcblookup(&V_tcbinfo,
pa->data.s_addr.v4,
pa->data.s_port,
pa->data.d_addr.v4,
pa->data.d_port,
INPLOOKUP_WLOCKPCB,
ifp);
break;
#endif
default:
CURVNET_RESTORE();
return (NULL);
}
CURVNET_RESTORE();
return (intotcpcb(inp));
}
static int
_tcp_lro_flush_tcphpts(struct lro_ctrl *lc, struct lro_entry *le)
{
struct tcpcb *tp;
struct mbuf **pp, *cmp, *mv_to;
struct ifnet *lagg_ifp;
bool bpf_req, lagg_bpf_req, should_wake, can_append_old_cmp;
/* Check if packet doesn't belongs to our network interface. */
if ((tcplro_stacks_wanting_mbufq == 0) ||
(le->outer.data.vlan_id != 0) ||
(le->inner.data.lro_type != LRO_TYPE_NONE))
return (TCP_LRO_CANNOT);
#ifdef INET6
/*
* 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.
*/
if (__predict_false(le->outer.data.lro_type == LRO_TYPE_IPV6_TCP &&
IN6_IS_ADDR_UNSPECIFIED(&le->outer.data.s_addr.v6)))
return (TCP_LRO_CANNOT);
if (__predict_false(le->inner.data.lro_type == LRO_TYPE_IPV6_TCP &&
IN6_IS_ADDR_UNSPECIFIED(&le->inner.data.s_addr.v6)))
return (TCP_LRO_CANNOT);
#endif
/* Lookup inp, if any. Returns locked TCP inpcb. */
tp = tcp_lro_lookup(lc->ifp,
(le->inner.data.lro_type == LRO_TYPE_NONE) ? &le->outer : &le->inner);
if (tp == NULL)
return (TCP_LRO_CANNOT);
counter_u64_add(tcp_inp_lro_locks_taken, 1);
/* Check if the inp is dead, Jim. */
if (tp->t_state == TCPS_TIME_WAIT) {
INP_WUNLOCK(tptoinpcb(tp));
return (TCP_LRO_CANNOT);
}
if (tp->t_lro_cpu == HPTS_CPU_NONE && lc->lro_cpu_is_set == 1)
tp->t_lro_cpu = lc->lro_last_cpu;
/* Check if the transport doesn't support the needed optimizations. */
if ((tp->t_flags2 & (TF2_SUPPORTS_MBUFQ | TF2_MBUF_ACKCMP)) == 0) {
INP_WUNLOCK(tptoinpcb(tp));
return (TCP_LRO_CANNOT);
}
if (tp->t_flags2 & TF2_MBUF_QUEUE_READY)
should_wake = false;
else
should_wake = true;
/* Check if packets should be tapped to BPF. */
bpf_req = bpf_peers_present(lc->ifp->if_bpf);
lagg_bpf_req = false;
lagg_ifp = NULL;
if (lc->ifp->if_type == IFT_IEEE8023ADLAG ||
lc->ifp->if_type == IFT_INFINIBANDLAG) {
struct lagg_port *lp = lc->ifp->if_lagg;
struct lagg_softc *sc = lp->lp_softc;
lagg_ifp = sc->sc_ifp;
if (lagg_ifp != NULL)
lagg_bpf_req = bpf_peers_present(lagg_ifp->if_bpf);
}
/* Strip and compress all the incoming packets. */
can_append_old_cmp = true;
cmp = NULL;
for (pp = &le->m_head; *pp != NULL; ) {
mv_to = NULL;
if (do_bpf_strip_and_compress(tp, lc, le, pp, &cmp, &mv_to,
&should_wake, bpf_req, lagg_bpf_req, lagg_ifp,
can_append_old_cmp) == false) {
/* Advance to next mbuf. */
pp = &(*pp)->m_nextpkt;
/*
* Once we have appended we can't look in the pending
* inbound packets for a compressed ack to append to.
*/
can_append_old_cmp = false;
/*
* Once we append we also need to stop adding to any
* compressed ack we were remembering. A new cmp
* ack will be required.
*/
cmp = NULL;
tcp_lro_log(tp, lc, le, NULL, 25, 0, 0, 0, 0);
} else if (mv_to != NULL) {
/* We are asked to move pp up */
pp = &mv_to->m_nextpkt;
tcp_lro_log(tp, lc, le, NULL, 24, 0, 0, 0, 0);
} else
tcp_lro_log(tp, lc, le, NULL, 26, 0, 0, 0, 0);
}
/* Update "m_last_mbuf", if any. */
if (pp == &le->m_head)
le->m_last_mbuf = *pp;
else
le->m_last_mbuf = __containerof(pp, struct mbuf, m_nextpkt);
/* Check if any data mbufs left. */
if (le->m_head != NULL) {
counter_u64_add(tcp_inp_lro_direct_queue, 1);
tcp_lro_log(tp, lc, le, NULL, 22, 1, tp->t_flags2, 0, 1);
tcp_queue_pkts(tp, le);
}
if (should_wake) {
/* Wakeup */
counter_u64_add(tcp_inp_lro_wokeup_queue, 1);
if ((*tp->t_fb->tfb_do_queued_segments)(tp, 0))
/* TCP cb gone and unlocked. */
return (0);
}
INP_WUNLOCK(tptoinpcb(tp));
return (0); /* Success. */
}
void
tcp_lro_hpts_init(void)
{
tcp_lro_flush_tcphpts = _tcp_lro_flush_tcphpts;
}
void
tcp_lro_hpts_uninit(void)
{
atomic_store_ptr(&tcp_lro_flush_tcphpts, NULL);
}
diff --git a/sys/netinet/tcp_stacks/rack_bbr_common.c b/sys/netinet/tcp_stacks/rack_bbr_common.c
index b265e8e6f20b..4a4a8af2bd78 100644
--- a/sys/netinet/tcp_stacks/rack_bbr_common.c
+++ b/sys/netinet/tcp_stacks/rack_bbr_common.c
@@ -1,1024 +1,1020 @@
/*-
* Copyright (c) 2016-2020 Netflix, 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.
*
* 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.
*
*/
/*
* Author: Randall Stewart <rrs@netflix.com>
* This work is based on the ACM Queue paper
* BBR - Congestion Based Congestion Control
* and also numerous discussions with Neal, Yuchung and Van.
*/
#include <sys/cdefs.h>
#include "opt_inet.h"
#include "opt_inet6.h"
#include "opt_ipsec.h"
#include "opt_ratelimit.h"
#include <sys/param.h>
#include <sys/arb.h>
#include <sys/module.h>
#include <sys/kernel.h>
#ifdef TCP_HHOOK
#include <sys/hhook.h>
#endif
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/proc.h>
#include <sys/qmath.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sysctl.h>
#include <sys/systm.h>
#include <sys/tree.h>
#ifdef NETFLIX_STATS
#include <sys/stats.h> /* Must come after qmath.h and tree.h */
#endif
#include <sys/refcount.h>
#include <sys/queue.h>
#include <sys/smp.h>
#include <sys/kthread.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/tim_filter.h>
#include <sys/time.h>
#include <vm/uma.h>
#include <sys/kern_prefetch.h>
#include <net/route.h>
#include <net/vnet.h>
#include <net/ethernet.h>
#include <net/bpf.h>
#define TCPSTATES /* for logging */
#include <netinet/in.h>
#include <netinet/in_kdtrace.h>
#include <netinet/in_pcb.h>
#include <netinet/ip.h>
#include <netinet/ip_icmp.h> /* required for icmp_var.h */
#include <netinet/icmp_var.h> /* for ICMP_BANDLIM */
#include <netinet/ip_var.h>
#include <netinet/ip6.h>
#include <netinet6/in6_pcb.h>
#include <netinet6/ip6_var.h>
#include <netinet/tcp.h>
#include <netinet/tcp_fsm.h>
#include <netinet/tcp_seq.h>
#include <netinet/tcp_timer.h>
#include <netinet/tcp_var.h>
#include <netinet/tcpip.h>
#include <netinet/tcp_ecn.h>
#include <netinet/tcp_hpts.h>
#include <netinet/tcp_lro.h>
#include <netinet/cc/cc.h>
#include <netinet/tcp_log_buf.h>
#ifdef TCP_OFFLOAD
#include <netinet/tcp_offload.h>
#endif
#ifdef INET6
#include <netinet6/tcp6_var.h>
#endif
#include <netinet/tcp_fastopen.h>
#include <netipsec/ipsec_support.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/if_private.h>
#if defined(IPSEC) || defined(IPSEC_SUPPORT)
#include <netipsec/ipsec.h>
#include <netipsec/ipsec6.h>
#endif /* IPSEC */
#include <netinet/udp.h>
#include <netinet/udp_var.h>
#include <machine/in_cksum.h>
#ifdef MAC
#include <security/mac/mac_framework.h>
#endif
#include "rack_bbr_common.h"
/*
* Common TCP Functions - These are shared by borth
* rack and BBR.
*/
static int
ctf_get_enet_type(struct ifnet *ifp, struct mbuf *m)
{
struct ether_header *eh;
#ifdef INET6
struct ip6_hdr *ip6 = NULL; /* Keep compiler happy. */
#endif
#ifdef INET
struct ip *ip = NULL; /* Keep compiler happy. */
#endif
#if defined(INET) || defined(INET6)
struct tcphdr *th;
int32_t tlen;
uint16_t drop_hdrlen;
#endif
uint16_t etype;
#ifdef INET
uint8_t iptos;
#endif
/* Is it the easy way? */
if (m->m_flags & M_LRO_EHDRSTRP)
return (m->m_pkthdr.lro_etype);
/*
* Ok this is the old style call, the ethernet header is here.
* This also means no checksum or BPF were done. This
* can happen if the race to setup the inp fails and
* LRO sees no INP at packet input, but by the time
* we queue the packets an INP gets there. Its rare
* but it can occur so we will handle it. Note that
* this means duplicated work but with the rarity of it
* its not worth worrying about.
*/
/* Let the BPF see the packet */
if (bpf_peers_present(ifp->if_bpf))
ETHER_BPF_MTAP(ifp, m);
/* Now the csum */
eh = mtod(m, struct ether_header *);
etype = ntohs(eh->ether_type);
m_adj(m, sizeof(*eh));
switch (etype) {
#ifdef INET6
case ETHERTYPE_IPV6:
{
if (m->m_len < (sizeof(*ip6) + sizeof(*th))) {
m = m_pullup(m, sizeof(*ip6) + sizeof(*th));
if (m == NULL) {
KMOD_TCPSTAT_INC(tcps_rcvshort);
return (-1);
}
}
ip6 = (struct ip6_hdr *)(eh + 1);
th = (struct tcphdr *)(ip6 + 1);
drop_hdrlen = sizeof(*ip6);
tlen = ntohs(ip6->ip6_plen);
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, drop_hdrlen, tlen);
if (th->th_sum) {
KMOD_TCPSTAT_INC(tcps_rcvbadsum);
m_freem(m);
return (-1);
}
return (etype);
}
#endif
#ifdef INET
case ETHERTYPE_IP:
{
if (m->m_len < sizeof (struct tcpiphdr)) {
m = m_pullup(m, sizeof (struct tcpiphdr));
if (m == NULL) {
KMOD_TCPSTAT_INC(tcps_rcvshort);
return (-1);
}
}
ip = (struct ip *)(eh + 1);
th = (struct tcphdr *)(ip + 1);
drop_hdrlen = sizeof(*ip);
iptos = ip->ip_tos;
tlen = ntohs(ip->ip_len) - sizeof(struct ip);
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 {
int len;
struct ipovly *ipov = (struct ipovly *)ip;
/*
* Checksum extended TCP header and data.
*/
len = drop_hdrlen + tlen;
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_v = IPVERSION;
ip->ip_hl = sizeof(*ip) >> 2;
}
if (th->th_sum) {
KMOD_TCPSTAT_INC(tcps_rcvbadsum);
m_freem(m);
return (-1);
}
break;
}
#endif
};
return (etype);
}
/*
* The function ctf_process_inbound_raw() is used by
* transport developers to do the steps needed to
* support MBUF Queuing i.e. the flags in
* inp->inp_flags2:
*
* - INP_SUPPORTS_MBUFQ
* - INP_MBUF_QUEUE_READY
* - INP_DONT_SACK_QUEUE
* - INP_MBUF_ACKCMP
*
* These flags help control how LRO will deliver
* packets to the transport. You first set in inp_flags2
* the INP_SUPPORTS_MBUFQ to tell the LRO code that you
* will gladly take a queue of packets instead of a compressed
* single packet. You also set in your t_fb pointer the
* tfb_do_queued_segments to point to ctf_process_inbound_raw.
*
* This then gets you lists of inbound ACK's/Data instead
* of a condensed compressed ACK/DATA packet. Why would you
* want that? This will get you access to all the arrival
* times of at least LRO and possibly at the Hardware (if
* the interface card supports that) of the actual ACK/DATA.
* In some transport designs this is important since knowing
* the actual time we got the packet is useful information.
*
* A new special type of mbuf may also be supported by the transport
* if it has set the INP_MBUF_ACKCMP flag. If its set, LRO will
* possibly create a M_ACKCMP type mbuf. This is a mbuf with
* an array of "acks". One thing also to note is that when this
* occurs a subsequent LRO may find at the back of the untouched
* mbuf queue chain a M_ACKCMP and append on to it. This means
* that until the transport pulls in the mbuf chain queued
* for it more ack's may get on the mbufs that were already
* delivered. There currently is a limit of 6 acks condensed
* into 1 mbuf which means often when this is occuring, we
* don't get that effect but it does happen.
*
* Now there are some interesting Caveats that the transport
* designer needs to take into account when using this feature.
*
* 1) It is used with HPTS and pacing, when the pacing timer
* for output calls it will first call the input.
* 2) When you set INP_MBUF_QUEUE_READY this tells LRO
* queue normal packets, I am busy pacing out data and
* will process the queued packets before my tfb_tcp_output
* call from pacing. If a non-normal packet arrives, (e.g. sack)
* you will be awoken immediately.
* 3) Finally you can add the INP_DONT_SACK_QUEUE to not even
* be awoken if a SACK has arrived. You would do this when
* you were not only running a pacing for output timer
* but a Rack timer as well i.e. you know you are in recovery
* and are in the process (via the timers) of dealing with
* the loss.
*
* Now a critical thing you must be aware of here is that the
* use of the flags has a far greater scope then just your
* typical LRO. Why? Well thats because in the normal compressed
* LRO case at the end of a driver interupt all packets are going
* to get presented to the transport no matter if there is one
* or 100. With the MBUF_QUEUE model, this is not true. You will
* only be awoken to process the queue of packets when:
* a) The flags discussed above allow it.
* <or>
* b) You exceed a ack or data limit (by default the
* ack limit is infinity (64k acks) and the data
* limit is 64k of new TCP data)
* <or>
* c) The push bit has been set by the peer
*/
static int
ctf_process_inbound_raw(struct tcpcb *tp, struct mbuf *m, int has_pkt)
{
/*
* We are passed a raw change of mbuf packets
* that arrived in LRO. They are linked via
* the m_nextpkt link in the pkt-headers.
*
* We process each one by:
* a) saving off the next
* b) stripping off the ether-header
* c) formulating the arguments for tfb_do_segment_nounlock()
* d) calling each mbuf to tfb_do_segment_nounlock()
* after adjusting the time to match the arrival time.
* Note that the LRO code assures no IP options are present.
*
* The symantics for calling tfb_do_segment_nounlock() are the
* following:
* 1) It returns 0 if all went well and you (the caller) need
* to release the lock.
* 2) If nxt_pkt is set, then the function will surpress calls
* to tcp_output() since you are promising to call again
* with another packet.
* 3) If it returns 1, then you must free all the packets being
* shipped in, the tcb has been destroyed (or about to be destroyed).
*/
struct mbuf *m_save;
struct tcphdr *th;
#ifdef INET6
struct ip6_hdr *ip6 = NULL; /* Keep compiler happy. */
#endif
#ifdef INET
struct ip *ip = NULL; /* Keep compiler happy. */
#endif
struct ifnet *ifp;
struct timeval tv;
struct inpcb *inp __diagused;
int32_t retval, nxt_pkt, tlen, off;
int etype = 0;
uint16_t drop_hdrlen;
uint8_t iptos, no_vn=0;
inp = tptoinpcb(tp);
INP_WLOCK_ASSERT(inp);
NET_EPOCH_ASSERT();
if (m)
ifp = m_rcvif(m);
else
ifp = NULL;
if (ifp == NULL) {
/*
* We probably should not work around
* but kassert, since lro alwasy sets rcvif.
*/
no_vn = 1;
goto skip_vnet;
}
CURVNET_SET(ifp->if_vnet);
skip_vnet:
tcp_get_usecs(&tv);
while (m) {
m_save = m->m_nextpkt;
m->m_nextpkt = NULL;
if ((m->m_flags & M_ACKCMP) == 0) {
/* Now lets get the ether header */
etype = ctf_get_enet_type(ifp, m);
if (etype == -1) {
/* Skip this packet it was freed by checksum */
goto skipped_pkt;
}
KASSERT(((etype == ETHERTYPE_IPV6) || (etype == ETHERTYPE_IP)),
("tp:%p m:%p etype:0x%x -- not IP or IPv6", tp, m, etype));
/* Trim off the ethernet header */
switch (etype) {
#ifdef INET6
case ETHERTYPE_IPV6:
ip6 = mtod(m, struct ip6_hdr *);
th = (struct tcphdr *)(ip6 + 1);
tlen = ntohs(ip6->ip6_plen);
drop_hdrlen = sizeof(*ip6);
iptos = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
break;
#endif
#ifdef INET
case ETHERTYPE_IP:
ip = mtod(m, struct ip *);
th = (struct tcphdr *)(ip + 1);
drop_hdrlen = sizeof(*ip);
iptos = ip->ip_tos;
tlen = ntohs(ip->ip_len) - sizeof(struct ip);
break;
#endif
} /* end switch */
- /*
- * Convert TCP protocol specific fields to host format.
- */
- tcp_fields_to_host(th);
off = th->th_off << 2;
if (off < sizeof (struct tcphdr) || off > tlen) {
printf("off:%d < hdrlen:%zu || > tlen:%u -- dump\n",
off,
sizeof(struct tcphdr),
tlen);
KMOD_TCPSTAT_INC(tcps_rcvbadoff);
m_freem(m);
goto skipped_pkt;
}
tlen -= off;
drop_hdrlen += off;
/*
* Now lets setup the timeval to be when we should
* have been called (if we can).
*/
m->m_pkthdr.lro_nsegs = 1;
/* Now what about next packet? */
} else {
/*
* This mbuf is an array of acks that have
* been compressed. We assert the inp has
* the flag set to enable this!
*/
KASSERT((tp->t_flags2 & TF2_MBUF_ACKCMP),
("tp:%p no TF2_MBUF_ACKCMP flags?", tp));
tlen = 0;
drop_hdrlen = 0;
th = NULL;
iptos = 0;
}
tcp_get_usecs(&tv);
if (m_save || has_pkt)
nxt_pkt = 1;
else
nxt_pkt = 0;
if ((m->m_flags & M_ACKCMP) == 0)
KMOD_TCPSTAT_INC(tcps_rcvtotal);
else
KMOD_TCPSTAT_ADD(tcps_rcvtotal, (m->m_len / sizeof(struct tcp_ackent)));
retval = (*tp->t_fb->tfb_do_segment_nounlock)(tp, m, th,
drop_hdrlen, tlen, iptos, nxt_pkt, &tv);
if (retval) {
/* We lost the lock and tcb probably */
m = m_save;
while(m) {
m_save = m->m_nextpkt;
m->m_nextpkt = NULL;
m_freem(m);
m = m_save;
}
if (no_vn == 0) {
CURVNET_RESTORE();
}
INP_UNLOCK_ASSERT(inp);
return(retval);
}
skipped_pkt:
m = m_save;
}
if (no_vn == 0) {
CURVNET_RESTORE();
}
return(retval);
}
int
ctf_do_queued_segments(struct tcpcb *tp, int have_pkt)
{
struct mbuf *m;
/* First lets see if we have old packets */
if ((m = STAILQ_FIRST(&tp->t_inqueue)) != NULL) {
STAILQ_INIT(&tp->t_inqueue);
if (ctf_process_inbound_raw(tp, m, have_pkt)) {
/* We lost the tcpcb (maybe a RST came in)? */
return(1);
}
}
return (0);
}
uint32_t
ctf_outstanding(struct tcpcb *tp)
{
uint32_t bytes_out;
bytes_out = tp->snd_max - tp->snd_una;
if (tp->t_state < TCPS_ESTABLISHED)
bytes_out++;
if (tp->t_flags & TF_SENTFIN)
bytes_out++;
return (bytes_out);
}
uint32_t
ctf_flight_size(struct tcpcb *tp, uint32_t rc_sacked)
{
if (rc_sacked <= ctf_outstanding(tp))
return(ctf_outstanding(tp) - rc_sacked);
else {
return (0);
}
}
void
ctf_do_dropwithreset(struct mbuf *m, struct tcpcb *tp, struct tcphdr *th,
int32_t rstreason, int32_t tlen)
{
if (tp != NULL) {
tcp_dropwithreset(m, th, tp, tlen, rstreason);
INP_WUNLOCK(tptoinpcb(tp));
} else
tcp_dropwithreset(m, th, NULL, tlen, rstreason);
}
void
ctf_ack_war_checks(struct tcpcb *tp, uint32_t *ts, uint32_t *cnt)
{
if ((ts != NULL) && (cnt != NULL) &&
(tcp_ack_war_time_window > 0) &&
(tcp_ack_war_cnt > 0)) {
/* We are possibly doing ack war prevention */
uint32_t cts;
/*
* We use a msec tick here which gives us
* roughly 49 days. We don't need the
* precision of a microsecond timestamp which
* would only give us hours.
*/
cts = tcp_ts_getticks();
if (TSTMP_LT((*ts), cts)) {
/* Timestamp is in the past */
*cnt = 0;
*ts = (cts + tcp_ack_war_time_window);
}
if (*cnt < tcp_ack_war_cnt) {
*cnt = (*cnt + 1);
tp->t_flags |= TF_ACKNOW;
} else
tp->t_flags &= ~TF_ACKNOW;
} else
tp->t_flags |= TF_ACKNOW;
}
/*
* ctf_drop_checks returns 1 for you should not proceed. It places
* in ret_val what should be returned 1/0 by the caller. The 1 indicates
* that the TCB is unlocked and probably dropped. The 0 indicates the
* TCB is still valid and locked.
*/
int
_ctf_drop_checks(struct tcpopt *to, struct mbuf *m, struct tcphdr *th,
struct tcpcb *tp, int32_t *tlenp,
int32_t *thf, int32_t *drop_hdrlen, int32_t *ret_val,
uint32_t *ts, uint32_t *cnt)
{
int32_t todrop;
int32_t thflags;
int32_t tlen;
thflags = *thf;
tlen = *tlenp;
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.
*/
ctf_ack_war_checks(tp, ts, cnt);
todrop = tlen;
KMOD_TCPSTAT_INC(tcps_rcvduppack);
KMOD_TCPSTAT_ADD(tcps_rcvdupbyte, todrop);
} else {
KMOD_TCPSTAT_INC(tcps_rcvpartduppack);
KMOD_TCPSTAT_ADD(tcps_rcvpartdupbyte, todrop);
}
/*
* DSACK - add SACK block for dropped range
*/
if ((todrop > 0) && (tp->t_flags & TF_SACK_PERMIT)) {
/*
* ACK now, as the next in-sequence segment
* will clear the DSACK block again
*/
ctf_ack_war_checks(tp, ts, cnt);
if (tp->t_flags & TF_ACKNOW)
tcp_update_sack_list(tp, th->th_seq,
th->th_seq + todrop);
}
*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 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) {
KMOD_TCPSTAT_INC(tcps_rcvpackafterwin);
if (todrop >= tlen) {
KMOD_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) {
ctf_ack_war_checks(tp, ts, cnt);
KMOD_TCPSTAT_INC(tcps_rcvwinprobe);
} else {
__ctf_do_dropafterack(m, tp, th, thflags, tlen, ret_val, ts, cnt);
return (1);
}
} else
KMOD_TCPSTAT_ADD(tcps_rcvbyteafterwin, todrop);
m_adj(m, -todrop);
tlen -= todrop;
thflags &= ~(TH_PUSH | TH_FIN);
}
*thf = thflags;
*tlenp = tlen;
return (0);
}
/*
* The value in ret_val informs the caller
* if we dropped the tcb (and lock) or not.
* 1 = we dropped it, 0 = the TCB is still locked
* and valid.
*/
void
__ctf_do_dropafterack(struct mbuf *m, struct tcpcb *tp, struct tcphdr *th, int32_t thflags, int32_t tlen, int32_t *ret_val, uint32_t *ts, uint32_t *cnt)
{
/*
* 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))) {
*ret_val = 1;
ctf_do_dropwithreset(m, tp, th, BANDLIM_RST_OPENPORT, tlen);
return;
} else
*ret_val = 0;
ctf_ack_war_checks(tp, ts, cnt);
if (m)
m_freem(m);
}
void
ctf_do_drop(struct mbuf *m, struct tcpcb *tp)
{
/*
* Drop space held by incoming segment and return.
*/
if (tp != NULL)
INP_WUNLOCK(tptoinpcb(tp));
if (m)
m_freem(m);
}
int
__ctf_process_rst(struct mbuf *m, struct tcphdr *th, struct socket *so,
struct tcpcb *tp, uint32_t *ts, uint32_t *cnt)
{
/*
* 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.
*/
int dropped = 0;
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) ||
(tp->rcv_nxt == th->th_seq)) {
KMOD_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:
tcp_state_change(tp, TCPS_CLOSED);
/* FALLTHROUGH */
default:
tcp_log_end_status(tp, TCP_EI_STATUS_CLIENT_RST);
tp = tcp_close(tp);
}
dropped = 1;
ctf_do_drop(m, tp);
} else {
int send_challenge;
KMOD_TCPSTAT_INC(tcps_badrst);
if ((ts != NULL) && (cnt != NULL) &&
(tcp_ack_war_time_window > 0) &&
(tcp_ack_war_cnt > 0)) {
/* We are possibly preventing an ack-rst war prevention */
uint32_t cts;
/*
* We use a msec tick here which gives us
* roughly 49 days. We don't need the
* precision of a microsecond timestamp which
* would only give us hours.
*/
cts = tcp_ts_getticks();
if (TSTMP_LT((*ts), cts)) {
/* Timestamp is in the past */
*cnt = 0;
*ts = (cts + tcp_ack_war_time_window);
}
if (*cnt < tcp_ack_war_cnt) {
*cnt = (*cnt + 1);
send_challenge = 1;
} else
send_challenge = 0;
} else
send_challenge = 1;
if (send_challenge) {
/* 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;
}
}
} else {
m_freem(m);
}
return (dropped);
}
/*
* The value in ret_val informs the caller
* if we dropped the tcb (and lock) or not.
* 1 = we dropped it, 0 = the TCB is still locked
* and valid.
*/
void
ctf_challenge_ack(struct mbuf *m, struct tcphdr *th, struct tcpcb *tp, uint8_t iptos, int32_t * ret_val)
{
NET_EPOCH_ASSERT();
KMOD_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)) {
tp = tcp_drop(tp, ECONNRESET);
*ret_val = 1;
ctf_do_drop(m, tp);
} else {
tcp_ecn_input_syn_sent(tp, tcp_get_flags(th), iptos);
/* 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;
m = NULL;
*ret_val = 0;
ctf_do_drop(m, NULL);
}
}
/*
* ctf_ts_check returns 1 for you should not proceed, the state
* machine should return. It places in ret_val what should
* be returned 1/0 by the caller (hpts_do_segment). The 1 indicates
* that the TCB is unlocked and probably dropped. The 0 indicates the
* TCB is still valid and locked.
*/
int
ctf_ts_check(struct mbuf *m, struct tcphdr *th, struct tcpcb *tp,
int32_t tlen, int32_t thflags, int32_t * ret_val)
{
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 {
KMOD_TCPSTAT_INC(tcps_rcvduppack);
KMOD_TCPSTAT_ADD(tcps_rcvdupbyte, tlen);
KMOD_TCPSTAT_INC(tcps_pawsdrop);
*ret_val = 0;
if (tlen) {
ctf_do_dropafterack(m, tp, th, thflags, tlen, ret_val);
} else {
ctf_do_drop(m, NULL);
}
return (1);
}
return (0);
}
int
ctf_ts_check_ac(struct tcpcb *tp, int32_t thflags)
{
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 {
KMOD_TCPSTAT_INC(tcps_rcvduppack);
KMOD_TCPSTAT_INC(tcps_pawsdrop);
return (1);
}
return (0);
}
void
ctf_calc_rwin(struct socket *so, struct tcpcb *tp)
{
int32_t win;
/*
* 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));
}
void
ctf_do_dropwithreset_conn(struct mbuf *m, struct tcpcb *tp, struct tcphdr *th,
int32_t rstreason, int32_t tlen)
{
tcp_dropwithreset(m, th, tp, tlen, rstreason);
tp = tcp_drop(tp, ETIMEDOUT);
if (tp)
INP_WUNLOCK(tptoinpcb(tp));
}
uint32_t
ctf_fixed_maxseg(struct tcpcb *tp)
{
return (tcp_fixed_maxseg(tp));
}
void
ctf_log_sack_filter(struct tcpcb *tp, int num_sack_blks, struct sackblk *sack_blocks)
{
if (tcp_bblogging_on(tp)) {
union tcp_log_stackspecific log;
struct timeval tv;
memset(&log, 0, sizeof(log));
log.u_bbr.timeStamp = tcp_get_usecs(&tv);
log.u_bbr.flex8 = num_sack_blks;
if (num_sack_blks > 0) {
log.u_bbr.flex1 = sack_blocks[0].start;
log.u_bbr.flex2 = sack_blocks[0].end;
}
if (num_sack_blks > 1) {
log.u_bbr.flex3 = sack_blocks[1].start;
log.u_bbr.flex4 = sack_blocks[1].end;
}
if (num_sack_blks > 2) {
log.u_bbr.flex5 = sack_blocks[2].start;
log.u_bbr.flex6 = sack_blocks[2].end;
}
if (num_sack_blks > 3) {
log.u_bbr.applimited = sack_blocks[3].start;
log.u_bbr.pkts_out = sack_blocks[3].end;
}
TCP_LOG_EVENTP(tp, NULL,
&tptosocket(tp)->so_rcv,
&tptosocket(tp)->so_snd,
TCP_SACK_FILTER_RES, 0,
0, &log, false, &tv);
}
}
uint32_t
ctf_decay_count(uint32_t count, uint32_t decay)
{
/*
* Given a count, decay it by a set percentage. The
* percentage is in thousands i.e. 100% = 1000,
* 19.3% = 193.
*/
uint64_t perc_count, decay_per;
uint32_t decayed_count;
if (decay > 1000) {
/* We don't raise it */
return (count);
}
perc_count = count;
decay_per = decay;
perc_count *= decay_per;
perc_count /= 1000;
/*
* So now perc_count holds the
* count decay value.
*/
decayed_count = count - (uint32_t)perc_count;
return(decayed_count);
}
int32_t
ctf_progress_timeout_check(struct tcpcb *tp, bool log)
{
if (tp->t_maxunacktime && tp->t_acktime && TSTMP_GT(ticks, tp->t_acktime)) {
if ((ticks - tp->t_acktime) >= tp->t_maxunacktime) {
/*
* There is an assumption that the caller
* will drop the connection so we will
* increment the counters here.
*/
if (log)
tcp_log_end_status(tp, TCP_EI_STATUS_PROGRESS);
#ifdef NETFLIX_STATS
KMOD_TCPSTAT_INC(tcps_progdrops);
#endif
return (1);
}
}
return (0);
}