76039bc84f
to this event, adding if_var.h to files that do need it. Also, include all includes that now are included due to implicit pollution via if_var.h Sponsored by: Netflix Sponsored by: Nginx, Inc.
651 lines
16 KiB
C
651 lines
16 KiB
C
/*-
|
|
* 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.
|
|
* 4. 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.
|
|
*
|
|
* @(#)tcp_subr.c 8.2 (Berkeley) 5/24/95
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include "opt_inet.h"
|
|
#include "opt_inet6.h"
|
|
#include "opt_tcpdebug.h"
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/callout.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/sysctl.h>
|
|
#include <sys/malloc.h>
|
|
#include <sys/mbuf.h>
|
|
#include <sys/priv.h>
|
|
#include <sys/proc.h>
|
|
#include <sys/socket.h>
|
|
#include <sys/socketvar.h>
|
|
#include <sys/protosw.h>
|
|
#include <sys/random.h>
|
|
|
|
#include <vm/uma.h>
|
|
|
|
#include <net/route.h>
|
|
#include <net/if.h>
|
|
#include <net/if_var.h>
|
|
#include <net/vnet.h>
|
|
|
|
#include <netinet/in.h>
|
|
#include <netinet/in_pcb.h>
|
|
#include <netinet/in_systm.h>
|
|
#include <netinet/in_var.h>
|
|
#include <netinet/ip.h>
|
|
#include <netinet/ip_icmp.h>
|
|
#include <netinet/ip_var.h>
|
|
#ifdef INET6
|
|
#include <netinet/ip6.h>
|
|
#include <netinet6/in6_pcb.h>
|
|
#include <netinet6/ip6_var.h>
|
|
#include <netinet6/scope6_var.h>
|
|
#include <netinet6/nd6.h>
|
|
#endif
|
|
#include <netinet/tcp.h>
|
|
#include <netinet/tcp_fsm.h>
|
|
#include <netinet/tcp_seq.h>
|
|
#include <netinet/tcp_timer.h>
|
|
#include <netinet/tcp_var.h>
|
|
#ifdef INET6
|
|
#include <netinet6/tcp6_var.h>
|
|
#endif
|
|
#include <netinet/tcpip.h>
|
|
#ifdef TCPDEBUG
|
|
#include <netinet/tcp_debug.h>
|
|
#endif
|
|
#ifdef INET6
|
|
#include <netinet6/ip6protosw.h>
|
|
#endif
|
|
|
|
#include <machine/in_cksum.h>
|
|
|
|
#include <security/mac/mac_framework.h>
|
|
|
|
static VNET_DEFINE(uma_zone_t, tcptw_zone);
|
|
#define V_tcptw_zone VNET(tcptw_zone)
|
|
static int maxtcptw;
|
|
|
|
/*
|
|
* The timed wait queue contains references to each of the TCP sessions
|
|
* currently in the TIME_WAIT state. The queue pointers, including the
|
|
* queue pointers in each tcptw structure, are protected using the global
|
|
* tcbinfo lock, which must be held over queue iteration and modification.
|
|
*/
|
|
static VNET_DEFINE(TAILQ_HEAD(, tcptw), twq_2msl);
|
|
#define V_twq_2msl VNET(twq_2msl)
|
|
|
|
static void tcp_tw_2msl_reset(struct tcptw *, int);
|
|
static void tcp_tw_2msl_stop(struct tcptw *);
|
|
|
|
static int
|
|
tcptw_auto_size(void)
|
|
{
|
|
int halfrange;
|
|
|
|
/*
|
|
* Max out at half the ephemeral port range so that TIME_WAIT
|
|
* sockets don't tie up too many ephemeral ports.
|
|
*/
|
|
if (V_ipport_lastauto > V_ipport_firstauto)
|
|
halfrange = (V_ipport_lastauto - V_ipport_firstauto) / 2;
|
|
else
|
|
halfrange = (V_ipport_firstauto - V_ipport_lastauto) / 2;
|
|
/* Protect against goofy port ranges smaller than 32. */
|
|
return (imin(imax(halfrange, 32), maxsockets / 5));
|
|
}
|
|
|
|
static int
|
|
sysctl_maxtcptw(SYSCTL_HANDLER_ARGS)
|
|
{
|
|
int error, new;
|
|
|
|
if (maxtcptw == 0)
|
|
new = tcptw_auto_size();
|
|
else
|
|
new = maxtcptw;
|
|
error = sysctl_handle_int(oidp, &new, 0, req);
|
|
if (error == 0 && req->newptr)
|
|
if (new >= 32) {
|
|
maxtcptw = new;
|
|
uma_zone_set_max(V_tcptw_zone, maxtcptw);
|
|
}
|
|
return (error);
|
|
}
|
|
|
|
SYSCTL_PROC(_net_inet_tcp, OID_AUTO, maxtcptw, CTLTYPE_INT|CTLFLAG_RW,
|
|
&maxtcptw, 0, sysctl_maxtcptw, "IU",
|
|
"Maximum number of compressed TCP TIME_WAIT entries");
|
|
|
|
VNET_DEFINE(int, nolocaltimewait) = 0;
|
|
#define V_nolocaltimewait VNET(nolocaltimewait)
|
|
SYSCTL_VNET_INT(_net_inet_tcp, OID_AUTO, nolocaltimewait, CTLFLAG_RW,
|
|
&VNET_NAME(nolocaltimewait), 0,
|
|
"Do not create compressed TCP TIME_WAIT entries for local connections");
|
|
|
|
void
|
|
tcp_tw_zone_change(void)
|
|
{
|
|
|
|
if (maxtcptw == 0)
|
|
uma_zone_set_max(V_tcptw_zone, tcptw_auto_size());
|
|
}
|
|
|
|
void
|
|
tcp_tw_init(void)
|
|
{
|
|
|
|
V_tcptw_zone = uma_zcreate("tcptw", sizeof(struct tcptw),
|
|
NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE);
|
|
TUNABLE_INT_FETCH("net.inet.tcp.maxtcptw", &maxtcptw);
|
|
if (maxtcptw == 0)
|
|
uma_zone_set_max(V_tcptw_zone, tcptw_auto_size());
|
|
else
|
|
uma_zone_set_max(V_tcptw_zone, maxtcptw);
|
|
TAILQ_INIT(&V_twq_2msl);
|
|
}
|
|
|
|
#ifdef VIMAGE
|
|
void
|
|
tcp_tw_destroy(void)
|
|
{
|
|
struct tcptw *tw;
|
|
|
|
INP_INFO_WLOCK(&V_tcbinfo);
|
|
while((tw = TAILQ_FIRST(&V_twq_2msl)) != NULL)
|
|
tcp_twclose(tw, 0);
|
|
INP_INFO_WUNLOCK(&V_tcbinfo);
|
|
|
|
uma_zdestroy(V_tcptw_zone);
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Move a TCP connection into TIME_WAIT state.
|
|
* tcbinfo is locked.
|
|
* inp is locked, and is unlocked before returning.
|
|
*/
|
|
void
|
|
tcp_twstart(struct tcpcb *tp)
|
|
{
|
|
struct tcptw *tw;
|
|
struct inpcb *inp = tp->t_inpcb;
|
|
int acknow;
|
|
struct socket *so;
|
|
#ifdef INET6
|
|
int isipv6 = inp->inp_inc.inc_flags & INC_ISIPV6;
|
|
#endif
|
|
|
|
INP_INFO_WLOCK_ASSERT(&V_tcbinfo); /* tcp_tw_2msl_reset(). */
|
|
INP_WLOCK_ASSERT(inp);
|
|
|
|
if (V_nolocaltimewait) {
|
|
int error = 0;
|
|
#ifdef INET6
|
|
if (isipv6)
|
|
error = in6_localaddr(&inp->in6p_faddr);
|
|
#endif
|
|
#if defined(INET6) && defined(INET)
|
|
else
|
|
#endif
|
|
#ifdef INET
|
|
error = in_localip(inp->inp_faddr);
|
|
#endif
|
|
if (error) {
|
|
tp = tcp_close(tp);
|
|
if (tp != NULL)
|
|
INP_WUNLOCK(inp);
|
|
return;
|
|
}
|
|
}
|
|
|
|
tw = uma_zalloc(V_tcptw_zone, M_NOWAIT);
|
|
if (tw == NULL) {
|
|
tw = tcp_tw_2msl_scan(1);
|
|
if (tw == NULL) {
|
|
tp = tcp_close(tp);
|
|
if (tp != NULL)
|
|
INP_WUNLOCK(inp);
|
|
return;
|
|
}
|
|
}
|
|
tw->tw_inpcb = inp;
|
|
|
|
/*
|
|
* Recover last window size sent.
|
|
*/
|
|
if (SEQ_GT(tp->rcv_adv, tp->rcv_nxt))
|
|
tw->last_win = (tp->rcv_adv - tp->rcv_nxt) >> tp->rcv_scale;
|
|
else
|
|
tw->last_win = 0;
|
|
|
|
/*
|
|
* Set t_recent if timestamps are used on the connection.
|
|
*/
|
|
if ((tp->t_flags & (TF_REQ_TSTMP|TF_RCVD_TSTMP|TF_NOOPT)) ==
|
|
(TF_REQ_TSTMP|TF_RCVD_TSTMP)) {
|
|
tw->t_recent = tp->ts_recent;
|
|
tw->ts_offset = tp->ts_offset;
|
|
} else {
|
|
tw->t_recent = 0;
|
|
tw->ts_offset = 0;
|
|
}
|
|
|
|
tw->snd_nxt = tp->snd_nxt;
|
|
tw->rcv_nxt = tp->rcv_nxt;
|
|
tw->iss = tp->iss;
|
|
tw->irs = tp->irs;
|
|
tw->t_starttime = tp->t_starttime;
|
|
tw->tw_time = 0;
|
|
|
|
/* XXX
|
|
* If this code will
|
|
* be used for fin-wait-2 state also, then we may need
|
|
* a ts_recent from the last segment.
|
|
*/
|
|
acknow = tp->t_flags & TF_ACKNOW;
|
|
|
|
/*
|
|
* First, discard tcpcb state, which includes stopping its timers and
|
|
* freeing it. tcp_discardcb() used to also release the inpcb, but
|
|
* that work is now done in the caller.
|
|
*
|
|
* Note: soisdisconnected() call used to be made in tcp_discardcb(),
|
|
* and might not be needed here any longer.
|
|
*/
|
|
tcp_discardcb(tp);
|
|
so = inp->inp_socket;
|
|
soisdisconnected(so);
|
|
tw->tw_cred = crhold(so->so_cred);
|
|
SOCK_LOCK(so);
|
|
tw->tw_so_options = so->so_options;
|
|
SOCK_UNLOCK(so);
|
|
if (acknow)
|
|
tcp_twrespond(tw, TH_ACK);
|
|
inp->inp_ppcb = tw;
|
|
inp->inp_flags |= INP_TIMEWAIT;
|
|
tcp_tw_2msl_reset(tw, 0);
|
|
|
|
/*
|
|
* If the inpcb owns the sole reference to the socket, then we can
|
|
* detach and free the socket as it is not needed in time wait.
|
|
*/
|
|
if (inp->inp_flags & INP_SOCKREF) {
|
|
KASSERT(so->so_state & SS_PROTOREF,
|
|
("tcp_twstart: !SS_PROTOREF"));
|
|
inp->inp_flags &= ~INP_SOCKREF;
|
|
INP_WUNLOCK(inp);
|
|
ACCEPT_LOCK();
|
|
SOCK_LOCK(so);
|
|
so->so_state &= ~SS_PROTOREF;
|
|
sofree(so);
|
|
} else
|
|
INP_WUNLOCK(inp);
|
|
}
|
|
|
|
#if 0
|
|
/*
|
|
* The appromixate rate of ISN increase of Microsoft TCP stacks;
|
|
* the actual rate is slightly higher due to the addition of
|
|
* random positive increments.
|
|
*
|
|
* Most other new OSes use semi-randomized ISN values, so we
|
|
* do not need to worry about them.
|
|
*/
|
|
#define MS_ISN_BYTES_PER_SECOND 250000
|
|
|
|
/*
|
|
* Determine if the ISN we will generate has advanced beyond the last
|
|
* sequence number used by the previous connection. If so, indicate
|
|
* that it is safe to recycle this tw socket by returning 1.
|
|
*/
|
|
int
|
|
tcp_twrecycleable(struct tcptw *tw)
|
|
{
|
|
tcp_seq new_iss = tw->iss;
|
|
tcp_seq new_irs = tw->irs;
|
|
|
|
INP_INFO_WLOCK_ASSERT(&V_tcbinfo);
|
|
new_iss += (ticks - tw->t_starttime) * (ISN_BYTES_PER_SECOND / hz);
|
|
new_irs += (ticks - tw->t_starttime) * (MS_ISN_BYTES_PER_SECOND / hz);
|
|
|
|
if (SEQ_GT(new_iss, tw->snd_nxt) && SEQ_GT(new_irs, tw->rcv_nxt))
|
|
return (1);
|
|
else
|
|
return (0);
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Returns 1 if the TIME_WAIT state was killed and we should start over,
|
|
* looking for a pcb in the listen state. Returns 0 otherwise.
|
|
*/
|
|
int
|
|
tcp_twcheck(struct inpcb *inp, struct tcpopt *to, struct tcphdr *th,
|
|
struct mbuf *m, int tlen)
|
|
{
|
|
struct tcptw *tw;
|
|
int thflags;
|
|
tcp_seq seq;
|
|
|
|
/* tcbinfo lock required for tcp_twclose(), tcp_tw_2msl_reset(). */
|
|
INP_INFO_WLOCK_ASSERT(&V_tcbinfo);
|
|
INP_WLOCK_ASSERT(inp);
|
|
|
|
/*
|
|
* XXXRW: Time wait state for inpcb has been recycled, but inpcb is
|
|
* still present. This is undesirable, but temporarily necessary
|
|
* until we work out how to handle inpcb's who's timewait state has
|
|
* been removed.
|
|
*/
|
|
tw = intotw(inp);
|
|
if (tw == NULL)
|
|
goto drop;
|
|
|
|
thflags = th->th_flags;
|
|
|
|
/*
|
|
* NOTE: for FIN_WAIT_2 (to be added later),
|
|
* must validate sequence number before accepting RST
|
|
*/
|
|
|
|
/*
|
|
* If the segment contains RST:
|
|
* Drop the segment - see Stevens, vol. 2, p. 964 and
|
|
* RFC 1337.
|
|
*/
|
|
if (thflags & TH_RST)
|
|
goto drop;
|
|
|
|
#if 0
|
|
/* PAWS not needed at the moment */
|
|
/*
|
|
* 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)) {
|
|
if ((thflags & TH_ACK) == 0)
|
|
goto drop;
|
|
goto ack;
|
|
}
|
|
/*
|
|
* ts_recent is never updated because we never accept new segments.
|
|
*/
|
|
#endif
|
|
|
|
/*
|
|
* If a new connection request is received
|
|
* while in TIME_WAIT, drop the old connection
|
|
* and start over if the sequence numbers
|
|
* are above the previous ones.
|
|
*/
|
|
if ((thflags & TH_SYN) && SEQ_GT(th->th_seq, tw->rcv_nxt)) {
|
|
tcp_twclose(tw, 0);
|
|
return (1);
|
|
}
|
|
|
|
/*
|
|
* Drop the segment if it does not contain an ACK.
|
|
*/
|
|
if ((thflags & TH_ACK) == 0)
|
|
goto drop;
|
|
|
|
/*
|
|
* Reset the 2MSL timer if this is a duplicate FIN.
|
|
*/
|
|
if (thflags & TH_FIN) {
|
|
seq = th->th_seq + tlen + (thflags & TH_SYN ? 1 : 0);
|
|
if (seq + 1 == tw->rcv_nxt)
|
|
tcp_tw_2msl_reset(tw, 1);
|
|
}
|
|
|
|
/*
|
|
* Acknowledge the segment if it has data or is not a duplicate ACK.
|
|
*/
|
|
if (thflags != TH_ACK || tlen != 0 ||
|
|
th->th_seq != tw->rcv_nxt || th->th_ack != tw->snd_nxt)
|
|
tcp_twrespond(tw, TH_ACK);
|
|
drop:
|
|
INP_WUNLOCK(inp);
|
|
m_freem(m);
|
|
return (0);
|
|
}
|
|
|
|
void
|
|
tcp_twclose(struct tcptw *tw, int reuse)
|
|
{
|
|
struct socket *so;
|
|
struct inpcb *inp;
|
|
|
|
/*
|
|
* At this point, we are in one of two situations:
|
|
*
|
|
* (1) We have no socket, just an inpcb<->twtcp pair. We can free
|
|
* all state.
|
|
*
|
|
* (2) We have a socket -- if we own a reference, release it and
|
|
* notify the socket layer.
|
|
*/
|
|
inp = tw->tw_inpcb;
|
|
KASSERT((inp->inp_flags & INP_TIMEWAIT), ("tcp_twclose: !timewait"));
|
|
KASSERT(intotw(inp) == tw, ("tcp_twclose: inp_ppcb != tw"));
|
|
INP_INFO_WLOCK_ASSERT(&V_tcbinfo); /* tcp_tw_2msl_stop(). */
|
|
INP_WLOCK_ASSERT(inp);
|
|
|
|
tw->tw_inpcb = NULL;
|
|
tcp_tw_2msl_stop(tw);
|
|
inp->inp_ppcb = NULL;
|
|
in_pcbdrop(inp);
|
|
|
|
so = inp->inp_socket;
|
|
if (so != NULL) {
|
|
/*
|
|
* If there's a socket, handle two cases: first, we own a
|
|
* strong reference, which we will now release, or we don't
|
|
* in which case another reference exists (XXXRW: think
|
|
* about this more), and we don't need to take action.
|
|
*/
|
|
if (inp->inp_flags & INP_SOCKREF) {
|
|
inp->inp_flags &= ~INP_SOCKREF;
|
|
INP_WUNLOCK(inp);
|
|
ACCEPT_LOCK();
|
|
SOCK_LOCK(so);
|
|
KASSERT(so->so_state & SS_PROTOREF,
|
|
("tcp_twclose: INP_SOCKREF && !SS_PROTOREF"));
|
|
so->so_state &= ~SS_PROTOREF;
|
|
sofree(so);
|
|
} else {
|
|
/*
|
|
* If we don't own the only reference, the socket and
|
|
* inpcb need to be left around to be handled by
|
|
* tcp_usr_detach() later.
|
|
*/
|
|
INP_WUNLOCK(inp);
|
|
}
|
|
} else
|
|
in_pcbfree(inp);
|
|
TCPSTAT_INC(tcps_closed);
|
|
crfree(tw->tw_cred);
|
|
tw->tw_cred = NULL;
|
|
if (reuse)
|
|
return;
|
|
uma_zfree(V_tcptw_zone, tw);
|
|
}
|
|
|
|
int
|
|
tcp_twrespond(struct tcptw *tw, int flags)
|
|
{
|
|
struct inpcb *inp = tw->tw_inpcb;
|
|
#if defined(INET6) || defined(INET)
|
|
struct tcphdr *th = NULL;
|
|
#endif
|
|
struct mbuf *m;
|
|
#ifdef INET
|
|
struct ip *ip = NULL;
|
|
#endif
|
|
u_int hdrlen, optlen;
|
|
int error = 0; /* Keep compiler happy */
|
|
struct tcpopt to;
|
|
#ifdef INET6
|
|
struct ip6_hdr *ip6 = NULL;
|
|
int isipv6 = inp->inp_inc.inc_flags & INC_ISIPV6;
|
|
#endif
|
|
hdrlen = 0; /* Keep compiler happy */
|
|
|
|
INP_WLOCK_ASSERT(inp);
|
|
|
|
m = m_gethdr(M_NOWAIT, MT_DATA);
|
|
if (m == NULL)
|
|
return (ENOBUFS);
|
|
m->m_data += max_linkhdr;
|
|
|
|
#ifdef MAC
|
|
mac_inpcb_create_mbuf(inp, m);
|
|
#endif
|
|
|
|
#ifdef INET6
|
|
if (isipv6) {
|
|
hdrlen = sizeof(struct ip6_hdr) + sizeof(struct tcphdr);
|
|
ip6 = mtod(m, struct ip6_hdr *);
|
|
th = (struct tcphdr *)(ip6 + 1);
|
|
tcpip_fillheaders(inp, ip6, th);
|
|
}
|
|
#endif
|
|
#if defined(INET6) && defined(INET)
|
|
else
|
|
#endif
|
|
#ifdef INET
|
|
{
|
|
hdrlen = sizeof(struct tcpiphdr);
|
|
ip = mtod(m, struct ip *);
|
|
th = (struct tcphdr *)(ip + 1);
|
|
tcpip_fillheaders(inp, ip, th);
|
|
}
|
|
#endif
|
|
to.to_flags = 0;
|
|
|
|
/*
|
|
* Send a timestamp and echo-reply if both our side and our peer
|
|
* have sent timestamps in our SYN's and this is not a RST.
|
|
*/
|
|
if (tw->t_recent && flags == TH_ACK) {
|
|
to.to_flags |= TOF_TS;
|
|
to.to_tsval = tcp_ts_getticks() + tw->ts_offset;
|
|
to.to_tsecr = tw->t_recent;
|
|
}
|
|
optlen = tcp_addoptions(&to, (u_char *)(th + 1));
|
|
|
|
m->m_len = hdrlen + optlen;
|
|
m->m_pkthdr.len = m->m_len;
|
|
|
|
KASSERT(max_linkhdr + m->m_len <= MHLEN, ("tcptw: mbuf too small"));
|
|
|
|
th->th_seq = htonl(tw->snd_nxt);
|
|
th->th_ack = htonl(tw->rcv_nxt);
|
|
th->th_off = (sizeof(struct tcphdr) + optlen) >> 2;
|
|
th->th_flags = flags;
|
|
th->th_win = htons(tw->last_win);
|
|
|
|
m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum);
|
|
#ifdef INET6
|
|
if (isipv6) {
|
|
m->m_pkthdr.csum_flags = CSUM_TCP_IPV6;
|
|
th->th_sum = in6_cksum_pseudo(ip6,
|
|
sizeof(struct tcphdr) + optlen, IPPROTO_TCP, 0);
|
|
ip6->ip6_hlim = in6_selecthlim(inp, NULL);
|
|
error = ip6_output(m, inp->in6p_outputopts, NULL,
|
|
(tw->tw_so_options & SO_DONTROUTE), NULL, NULL, inp);
|
|
}
|
|
#endif
|
|
#if defined(INET6) && defined(INET)
|
|
else
|
|
#endif
|
|
#ifdef INET
|
|
{
|
|
m->m_pkthdr.csum_flags = CSUM_TCP;
|
|
th->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr,
|
|
htons(sizeof(struct tcphdr) + optlen + IPPROTO_TCP));
|
|
ip->ip_len = htons(m->m_pkthdr.len);
|
|
if (V_path_mtu_discovery)
|
|
ip->ip_off |= htons(IP_DF);
|
|
error = ip_output(m, inp->inp_options, NULL,
|
|
((tw->tw_so_options & SO_DONTROUTE) ? IP_ROUTETOIF : 0),
|
|
NULL, inp);
|
|
}
|
|
#endif
|
|
if (flags & TH_ACK)
|
|
TCPSTAT_INC(tcps_sndacks);
|
|
else
|
|
TCPSTAT_INC(tcps_sndctrl);
|
|
TCPSTAT_INC(tcps_sndtotal);
|
|
return (error);
|
|
}
|
|
|
|
static void
|
|
tcp_tw_2msl_reset(struct tcptw *tw, int rearm)
|
|
{
|
|
|
|
INP_INFO_WLOCK_ASSERT(&V_tcbinfo);
|
|
INP_WLOCK_ASSERT(tw->tw_inpcb);
|
|
if (rearm)
|
|
TAILQ_REMOVE(&V_twq_2msl, tw, tw_2msl);
|
|
tw->tw_time = ticks + 2 * tcp_msl;
|
|
TAILQ_INSERT_TAIL(&V_twq_2msl, tw, tw_2msl);
|
|
}
|
|
|
|
static void
|
|
tcp_tw_2msl_stop(struct tcptw *tw)
|
|
{
|
|
|
|
INP_INFO_WLOCK_ASSERT(&V_tcbinfo);
|
|
TAILQ_REMOVE(&V_twq_2msl, tw, tw_2msl);
|
|
}
|
|
|
|
struct tcptw *
|
|
tcp_tw_2msl_scan(int reuse)
|
|
{
|
|
struct tcptw *tw;
|
|
|
|
INP_INFO_WLOCK_ASSERT(&V_tcbinfo);
|
|
for (;;) {
|
|
tw = TAILQ_FIRST(&V_twq_2msl);
|
|
if (tw == NULL || (!reuse && (tw->tw_time - ticks) > 0))
|
|
break;
|
|
INP_WLOCK(tw->tw_inpcb);
|
|
tcp_twclose(tw, reuse);
|
|
if (reuse)
|
|
return (tw);
|
|
}
|
|
return (NULL);
|
|
}
|