1463 lines
38 KiB
C
1463 lines
38 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.
|
|
* 3. All advertising materials mentioning features or use of this software
|
|
* must display the following acknowledgement:
|
|
* This product includes software developed by the University of
|
|
* California, Berkeley and its contributors.
|
|
* 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
|
|
* $FreeBSD$
|
|
*/
|
|
|
|
#include "opt_compat.h"
|
|
#include "opt_inet6.h"
|
|
#include "opt_ipsec.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>
|
|
#ifdef INET6
|
|
#include <sys/domain.h>
|
|
#endif
|
|
#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>
|
|
|
|
#define _IP_VHL
|
|
#include <netinet/in.h>
|
|
#include <netinet/in_systm.h>
|
|
#include <netinet/ip.h>
|
|
#ifdef INET6
|
|
#include <netinet/ip6.h>
|
|
#endif
|
|
#include <netinet/in_pcb.h>
|
|
#ifdef INET6
|
|
#include <netinet6/in6_pcb.h>
|
|
#endif
|
|
#include <netinet/in_var.h>
|
|
#include <netinet/ip_var.h>
|
|
#ifdef INET6
|
|
#include <netinet6/ip6_var.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
|
|
#include <netinet6/ip6protosw.h>
|
|
|
|
#ifdef IPSEC
|
|
#include <netinet6/ipsec.h>
|
|
#ifdef INET6
|
|
#include <netinet6/ipsec6.h>
|
|
#endif
|
|
#endif /*IPSEC*/
|
|
|
|
#include <machine/in_cksum.h>
|
|
#include <sys/md5.h>
|
|
|
|
int tcp_mssdflt = TCP_MSS;
|
|
SYSCTL_INT(_net_inet_tcp, TCPCTL_MSSDFLT, mssdflt, CTLFLAG_RW,
|
|
&tcp_mssdflt , 0, "Default TCP Maximum Segment Size");
|
|
|
|
#ifdef INET6
|
|
int tcp_v6mssdflt = TCP6_MSS;
|
|
SYSCTL_INT(_net_inet_tcp, TCPCTL_V6MSSDFLT, v6mssdflt,
|
|
CTLFLAG_RW, &tcp_v6mssdflt , 0,
|
|
"Default TCP Maximum Segment Size for IPv6");
|
|
#endif
|
|
|
|
#if 0
|
|
static int tcp_rttdflt = TCPTV_SRTTDFLT / PR_SLOWHZ;
|
|
SYSCTL_INT(_net_inet_tcp, TCPCTL_RTTDFLT, rttdflt, CTLFLAG_RW,
|
|
&tcp_rttdflt , 0, "Default maximum TCP Round Trip Time");
|
|
#endif
|
|
|
|
int tcp_do_rfc1323 = 1;
|
|
SYSCTL_INT(_net_inet_tcp, TCPCTL_DO_RFC1323, rfc1323, CTLFLAG_RW,
|
|
&tcp_do_rfc1323 , 0, "Enable rfc1323 (high performance TCP) extensions");
|
|
|
|
int tcp_do_rfc1644 = 0;
|
|
SYSCTL_INT(_net_inet_tcp, TCPCTL_DO_RFC1644, rfc1644, CTLFLAG_RW,
|
|
&tcp_do_rfc1644 , 0, "Enable rfc1644 (TTCP) extensions");
|
|
|
|
static int tcp_tcbhashsize = 0;
|
|
SYSCTL_INT(_net_inet_tcp, OID_AUTO, tcbhashsize, CTLFLAG_RD,
|
|
&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_INT(_net_inet_tcp, OID_AUTO, pcbcount, CTLFLAG_RD,
|
|
&tcbinfo.ipi_count, 0, "Number of active PCBs");
|
|
|
|
static int icmp_may_rst = 1;
|
|
SYSCTL_INT(_net_inet_tcp, OID_AUTO, icmp_may_rst, CTLFLAG_RW, &icmp_may_rst, 0,
|
|
"Certain ICMP unreachable messages may abort connections in SYN_SENT");
|
|
|
|
static int tcp_isn_reseed_interval = 0;
|
|
SYSCTL_INT(_net_inet_tcp, OID_AUTO, isn_reseed_interval, CTLFLAG_RW,
|
|
&tcp_isn_reseed_interval, 0, "Seconds between reseeding of ISN secret");
|
|
|
|
static void tcp_cleartaocache(void);
|
|
static void tcp_notify(struct inpcb *, int);
|
|
|
|
/*
|
|
* 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 512
|
|
#endif
|
|
|
|
/*
|
|
* This is the actual shape of what we allocate using the zone
|
|
* allocator. Doing it this way allows us to protect both structures
|
|
* using the same generation count, and also eliminates the overhead
|
|
* of allocating tcpcbs separately. By hiding the structure here,
|
|
* we avoid changing most of the rest of the code (although it needs
|
|
* to be changed, eventually, for greater efficiency).
|
|
*/
|
|
#define ALIGNMENT 32
|
|
#define ALIGNM1 (ALIGNMENT - 1)
|
|
struct inp_tp {
|
|
union {
|
|
struct inpcb inp;
|
|
char align[(sizeof(struct inpcb) + ALIGNM1) & ~ALIGNM1];
|
|
} inp_tp_u;
|
|
struct tcpcb tcb;
|
|
struct callout inp_tp_rexmt, inp_tp_persist, inp_tp_keep, inp_tp_2msl;
|
|
struct callout inp_tp_delack;
|
|
};
|
|
#undef ALIGNMENT
|
|
#undef ALIGNM1
|
|
|
|
/*
|
|
* Tcp initialization
|
|
*/
|
|
void
|
|
tcp_init()
|
|
{
|
|
int hashsize = TCBHASHSIZE;
|
|
|
|
tcp_ccgen = 1;
|
|
tcp_cleartaocache();
|
|
|
|
tcp_delacktime = TCPTV_DELACK;
|
|
tcp_keepinit = TCPTV_KEEP_INIT;
|
|
tcp_keepidle = TCPTV_KEEP_IDLE;
|
|
tcp_keepintvl = TCPTV_KEEPINTVL;
|
|
tcp_maxpersistidle = TCPTV_KEEP_IDLE;
|
|
tcp_msl = TCPTV_MSL;
|
|
|
|
LIST_INIT(&tcb);
|
|
tcbinfo.listhead = &tcb;
|
|
TUNABLE_INT_FETCH("net.inet.tcp.tcbhashsize", &hashsize);
|
|
if (!powerof2(hashsize)) {
|
|
printf("WARNING: TCB hash size not a power of 2\n");
|
|
hashsize = 512; /* safe default */
|
|
}
|
|
tcp_tcbhashsize = hashsize;
|
|
tcbinfo.hashbase = hashinit(hashsize, M_PCB, &tcbinfo.hashmask);
|
|
tcbinfo.porthashbase = hashinit(hashsize, M_PCB,
|
|
&tcbinfo.porthashmask);
|
|
tcbinfo.ipi_zone = uma_zcreate("tcpcb", sizeof(struct inp_tp),
|
|
NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE);
|
|
uma_zone_set_max(tcbinfo.ipi_zone, maxsockets);
|
|
#ifdef INET6
|
|
#define TCP_MINPROTOHDR (sizeof(struct ip6_hdr) + sizeof(struct tcphdr))
|
|
#else /* INET6 */
|
|
#define TCP_MINPROTOHDR (sizeof(struct tcpiphdr))
|
|
#endif /* INET6 */
|
|
if (max_protohdr < TCP_MINPROTOHDR)
|
|
max_protohdr = TCP_MINPROTOHDR;
|
|
if (max_linkhdr + TCP_MINPROTOHDR > MHLEN)
|
|
panic("tcp_init");
|
|
#undef TCP_MINPROTOHDR
|
|
|
|
syncache_init();
|
|
}
|
|
|
|
/*
|
|
* 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
|
|
tcp_fillheaders(tp, ip_ptr, tcp_ptr)
|
|
struct tcpcb *tp;
|
|
void *ip_ptr;
|
|
void *tcp_ptr;
|
|
{
|
|
struct inpcb *inp = tp->t_inpcb;
|
|
struct tcphdr *tcp_hdr = (struct tcphdr *)tcp_ptr;
|
|
|
|
#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->in6p_flowinfo & IPV6_FLOWINFO_MASK);
|
|
ip6->ip6_vfc = (ip6->ip6_vfc & ~IPV6_VERSION_MASK) |
|
|
(IPV6_VERSION & IPV6_VERSION_MASK);
|
|
ip6->ip6_nxt = IPPROTO_TCP;
|
|
ip6->ip6_plen = sizeof(struct tcphdr);
|
|
ip6->ip6_src = inp->in6p_laddr;
|
|
ip6->ip6_dst = inp->in6p_faddr;
|
|
tcp_hdr->th_sum = 0;
|
|
} else
|
|
#endif
|
|
{
|
|
struct ip *ip = (struct ip *) ip_ptr;
|
|
|
|
ip->ip_vhl = IP_VHL_BORING;
|
|
ip->ip_tos = 0;
|
|
ip->ip_len = 0;
|
|
ip->ip_id = 0;
|
|
ip->ip_off = 0;
|
|
ip->ip_ttl = 0;
|
|
ip->ip_sum = 0;
|
|
ip->ip_p = IPPROTO_TCP;
|
|
ip->ip_src = inp->inp_laddr;
|
|
ip->ip_dst = inp->inp_faddr;
|
|
tcp_hdr->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr,
|
|
htons(sizeof(struct tcphdr) + IPPROTO_TCP));
|
|
}
|
|
|
|
tcp_hdr->th_sport = inp->inp_lport;
|
|
tcp_hdr->th_dport = inp->inp_fport;
|
|
tcp_hdr->th_seq = 0;
|
|
tcp_hdr->th_ack = 0;
|
|
tcp_hdr->th_x2 = 0;
|
|
tcp_hdr->th_off = 5;
|
|
tcp_hdr->th_flags = 0;
|
|
tcp_hdr->th_win = 0;
|
|
tcp_hdr->th_urp = 0;
|
|
}
|
|
|
|
/*
|
|
* 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 *
|
|
tcp_maketemplate(tp)
|
|
struct tcpcb *tp;
|
|
{
|
|
struct mbuf *m;
|
|
struct tcptemp *n;
|
|
|
|
m = m_get(M_DONTWAIT, MT_HEADER);
|
|
if (m == NULL)
|
|
return (0);
|
|
m->m_len = sizeof(struct tcptemp);
|
|
n = mtod(m, struct tcptemp *);
|
|
|
|
tcp_fillheaders(tp, (void *)&n->tt_ipgen, (void *)&n->tt_t);
|
|
return (n);
|
|
}
|
|
|
|
/*
|
|
* Send a single message to the TCP at address specified by
|
|
* the given TCP/IP header. If m == 0, then we make a copy
|
|
* of the tcpiphdr at ti 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 ti,
|
|
* 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 ti must point to *inside* the mbuf.
|
|
*/
|
|
void
|
|
tcp_respond(tp, ipgen, th, m, ack, seq, flags)
|
|
struct tcpcb *tp;
|
|
void *ipgen;
|
|
register struct tcphdr *th;
|
|
register struct mbuf *m;
|
|
tcp_seq ack, seq;
|
|
int flags;
|
|
{
|
|
register int tlen;
|
|
int win = 0;
|
|
struct route *ro = 0;
|
|
struct route sro;
|
|
struct ip *ip;
|
|
struct tcphdr *nth;
|
|
#ifdef INET6
|
|
struct route_in6 *ro6 = 0;
|
|
struct route_in6 sro6;
|
|
struct ip6_hdr *ip6;
|
|
int isipv6;
|
|
#endif /* INET6 */
|
|
int ipflags = 0;
|
|
|
|
#ifdef INET6
|
|
isipv6 = IP_VHL_V(((struct ip *)ipgen)->ip_vhl) == 6;
|
|
ip6 = ipgen;
|
|
#endif /* INET6 */
|
|
ip = ipgen;
|
|
|
|
if (tp) {
|
|
if (!(flags & TH_RST)) {
|
|
win = sbspace(&tp->t_inpcb->inp_socket->so_rcv);
|
|
if (win > (long)TCP_MAXWIN << tp->rcv_scale)
|
|
win = (long)TCP_MAXWIN << tp->rcv_scale;
|
|
}
|
|
#ifdef INET6
|
|
if (isipv6)
|
|
ro6 = &tp->t_inpcb->in6p_route;
|
|
else
|
|
#endif /* INET6 */
|
|
ro = &tp->t_inpcb->inp_route;
|
|
} else {
|
|
#ifdef INET6
|
|
if (isipv6) {
|
|
ro6 = &sro6;
|
|
bzero(ro6, sizeof *ro6);
|
|
} else
|
|
#endif /* INET6 */
|
|
{
|
|
ro = &sro;
|
|
bzero(ro, sizeof *ro);
|
|
}
|
|
}
|
|
if (m == 0) {
|
|
m = m_gethdr(M_DONTWAIT, MT_HEADER);
|
|
if (m == NULL)
|
|
return;
|
|
tlen = 0;
|
|
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);
|
|
} else
|
|
#endif /* INET6 */
|
|
{
|
|
bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip));
|
|
ip = mtod(m, struct ip *);
|
|
nth = (struct tcphdr *)(ip + 1);
|
|
}
|
|
bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr));
|
|
flags = TH_ACK;
|
|
} else {
|
|
m_freem(m->m_next);
|
|
m->m_next = 0;
|
|
m->m_data = (caddr_t)ipgen;
|
|
/* m_len is set later */
|
|
tlen = 0;
|
|
#define xchg(a,b,type) { type t; t=a; a=b; b=t; }
|
|
#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, n_long);
|
|
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, n_short);
|
|
#undef xchg
|
|
}
|
|
#ifdef INET6
|
|
if (isipv6) {
|
|
ip6->ip6_flow = 0;
|
|
ip6->ip6_vfc = IPV6_VERSION;
|
|
ip6->ip6_nxt = IPPROTO_TCP;
|
|
ip6->ip6_plen = htons((u_short)(sizeof (struct tcphdr) +
|
|
tlen));
|
|
tlen += sizeof (struct ip6_hdr) + sizeof (struct tcphdr);
|
|
} else
|
|
#endif
|
|
{
|
|
tlen += sizeof (struct tcpiphdr);
|
|
ip->ip_len = tlen;
|
|
ip->ip_ttl = ip_defttl;
|
|
}
|
|
m->m_len = tlen;
|
|
m->m_pkthdr.len = tlen;
|
|
m->m_pkthdr.rcvif = (struct ifnet *) 0;
|
|
nth->th_seq = htonl(seq);
|
|
nth->th_ack = htonl(ack);
|
|
nth->th_x2 = 0;
|
|
nth->th_off = sizeof (struct tcphdr) >> 2;
|
|
nth->th_flags = flags;
|
|
if (tp)
|
|
nth->th_win = htons((u_short) (win >> tp->rcv_scale));
|
|
else
|
|
nth->th_win = htons((u_short)win);
|
|
nth->th_urp = 0;
|
|
#ifdef INET6
|
|
if (isipv6) {
|
|
nth->th_sum = 0;
|
|
nth->th_sum = in6_cksum(m, IPPROTO_TCP,
|
|
sizeof(struct ip6_hdr),
|
|
tlen - sizeof(struct ip6_hdr));
|
|
ip6->ip6_hlim = in6_selecthlim(tp ? tp->t_inpcb : NULL,
|
|
ro6 && ro6->ro_rt ?
|
|
ro6->ro_rt->rt_ifp :
|
|
NULL);
|
|
} else
|
|
#endif /* INET6 */
|
|
{
|
|
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)));
|
|
m->m_pkthdr.csum_flags = CSUM_TCP;
|
|
m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum);
|
|
}
|
|
#ifdef TCPDEBUG
|
|
if (tp == NULL || (tp->t_inpcb->inp_socket->so_options & SO_DEBUG))
|
|
tcp_trace(TA_OUTPUT, 0, tp, mtod(m, void *), th, 0);
|
|
#endif
|
|
#ifdef IPSEC
|
|
if (ipsec_setsocket(m, tp ? tp->t_inpcb->inp_socket : NULL) != 0) {
|
|
m_freem(m);
|
|
return;
|
|
}
|
|
#endif
|
|
#ifdef INET6
|
|
if (isipv6) {
|
|
(void)ip6_output(m, NULL, ro6, ipflags, NULL, NULL);
|
|
if (ro6 == &sro6 && ro6->ro_rt) {
|
|
RTFREE(ro6->ro_rt);
|
|
ro6->ro_rt = NULL;
|
|
}
|
|
} else
|
|
#endif /* INET6 */
|
|
{
|
|
(void) ip_output(m, NULL, ro, ipflags, NULL);
|
|
if (ro == &sro && ro->ro_rt) {
|
|
RTFREE(ro->ro_rt);
|
|
ro->ro_rt = NULL;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* 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 in tcp_init().
|
|
*/
|
|
struct tcpcb *
|
|
tcp_newtcpcb(inp)
|
|
struct inpcb *inp;
|
|
{
|
|
struct inp_tp *it;
|
|
register struct tcpcb *tp;
|
|
#ifdef INET6
|
|
int isipv6 = (inp->inp_vflag & INP_IPV6) != 0;
|
|
#endif /* INET6 */
|
|
|
|
it = (struct inp_tp *)inp;
|
|
tp = &it->tcb;
|
|
bzero((char *) tp, sizeof(struct tcpcb));
|
|
LIST_INIT(&tp->t_segq);
|
|
tp->t_maxseg = tp->t_maxopd =
|
|
#ifdef INET6
|
|
isipv6 ? tcp_v6mssdflt :
|
|
#endif /* INET6 */
|
|
tcp_mssdflt;
|
|
|
|
/* Set up our timeouts. */
|
|
callout_init(tp->tt_rexmt = &it->inp_tp_rexmt, 0);
|
|
callout_init(tp->tt_persist = &it->inp_tp_persist, 0);
|
|
callout_init(tp->tt_keep = &it->inp_tp_keep, 0);
|
|
callout_init(tp->tt_2msl = &it->inp_tp_2msl, 0);
|
|
callout_init(tp->tt_delack = &it->inp_tp_delack, 0);
|
|
|
|
if (tcp_do_rfc1323)
|
|
tp->t_flags = (TF_REQ_SCALE|TF_REQ_TSTMP);
|
|
if (tcp_do_rfc1644)
|
|
tp->t_flags |= TF_REQ_CC;
|
|
tp->t_inpcb = inp; /* XXX */
|
|
/*
|
|
* 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 = ((TCPTV_RTOBASE - TCPTV_SRTTBASE) << TCP_RTTVAR_SHIFT) / 4;
|
|
tp->t_rttmin = TCPTV_MIN;
|
|
tp->t_rxtcur = TCPTV_RTOBASE;
|
|
tp->snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT;
|
|
tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT;
|
|
tp->t_rcvtime = 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 = ip_defttl;
|
|
inp->inp_ppcb = (caddr_t)tp;
|
|
return (tp); /* XXX */
|
|
}
|
|
|
|
/*
|
|
* Drop a TCP connection, reporting
|
|
* the specified error. If connection is synchronized,
|
|
* then send a RST to peer.
|
|
*/
|
|
struct tcpcb *
|
|
tcp_drop(tp, errno)
|
|
register struct tcpcb *tp;
|
|
int errno;
|
|
{
|
|
struct socket *so = tp->t_inpcb->inp_socket;
|
|
|
|
if (TCPS_HAVERCVDSYN(tp->t_state)) {
|
|
tp->t_state = TCPS_CLOSED;
|
|
(void) tcp_output(tp);
|
|
tcpstat.tcps_drops++;
|
|
} else
|
|
tcpstat.tcps_conndrops++;
|
|
if (errno == ETIMEDOUT && tp->t_softerror)
|
|
errno = tp->t_softerror;
|
|
so->so_error = errno;
|
|
return (tcp_close(tp));
|
|
}
|
|
|
|
/*
|
|
* Close a TCP control block:
|
|
* discard all space held by the tcp
|
|
* discard internet protocol block
|
|
* wake up any sleepers
|
|
*/
|
|
struct tcpcb *
|
|
tcp_close(tp)
|
|
register struct tcpcb *tp;
|
|
{
|
|
register struct tseg_qent *q;
|
|
struct inpcb *inp = tp->t_inpcb;
|
|
struct socket *so = inp->inp_socket;
|
|
#ifdef INET6
|
|
int isipv6 = (inp->inp_vflag & INP_IPV6) != 0;
|
|
#endif /* INET6 */
|
|
register struct rtentry *rt;
|
|
int dosavessthresh;
|
|
|
|
/*
|
|
* Make sure that all of our timers are stopped before we
|
|
* delete the PCB.
|
|
*/
|
|
callout_stop(tp->tt_rexmt);
|
|
callout_stop(tp->tt_persist);
|
|
callout_stop(tp->tt_keep);
|
|
callout_stop(tp->tt_2msl);
|
|
callout_stop(tp->tt_delack);
|
|
|
|
/*
|
|
* If we got enough samples through the srtt filter,
|
|
* save the rtt and rttvar in the routing entry.
|
|
* 'Enough' is arbitrarily defined as the 16 samples.
|
|
* 16 samples is enough for the srtt filter to converge
|
|
* to within 5% of the correct value; fewer samples and
|
|
* we could save a very bogus rtt.
|
|
*
|
|
* Don't update the default route's characteristics and don't
|
|
* update anything that the user "locked".
|
|
*/
|
|
if (tp->t_rttupdated >= 16) {
|
|
register u_long i = 0;
|
|
#ifdef INET6
|
|
if (isipv6) {
|
|
struct sockaddr_in6 *sin6;
|
|
|
|
if ((rt = inp->in6p_route.ro_rt) == NULL)
|
|
goto no_valid_rt;
|
|
sin6 = (struct sockaddr_in6 *)rt_key(rt);
|
|
if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr))
|
|
goto no_valid_rt;
|
|
}
|
|
else
|
|
#endif /* INET6 */
|
|
if ((rt = inp->inp_route.ro_rt) == NULL ||
|
|
((struct sockaddr_in *)rt_key(rt))->sin_addr.s_addr
|
|
== INADDR_ANY)
|
|
goto no_valid_rt;
|
|
|
|
if ((rt->rt_rmx.rmx_locks & RTV_RTT) == 0) {
|
|
i = tp->t_srtt *
|
|
(RTM_RTTUNIT / (hz * TCP_RTT_SCALE));
|
|
if (rt->rt_rmx.rmx_rtt && i)
|
|
/*
|
|
* filter this update to half the old & half
|
|
* the new values, converting scale.
|
|
* See route.h and tcp_var.h for a
|
|
* description of the scaling constants.
|
|
*/
|
|
rt->rt_rmx.rmx_rtt =
|
|
(rt->rt_rmx.rmx_rtt + i) / 2;
|
|
else
|
|
rt->rt_rmx.rmx_rtt = i;
|
|
tcpstat.tcps_cachedrtt++;
|
|
}
|
|
if ((rt->rt_rmx.rmx_locks & RTV_RTTVAR) == 0) {
|
|
i = tp->t_rttvar *
|
|
(RTM_RTTUNIT / (hz * TCP_RTTVAR_SCALE));
|
|
if (rt->rt_rmx.rmx_rttvar && i)
|
|
rt->rt_rmx.rmx_rttvar =
|
|
(rt->rt_rmx.rmx_rttvar + i) / 2;
|
|
else
|
|
rt->rt_rmx.rmx_rttvar = i;
|
|
tcpstat.tcps_cachedrttvar++;
|
|
}
|
|
/*
|
|
* The old comment here said:
|
|
* update the pipelimit (ssthresh) if it has been updated
|
|
* already or if a pipesize was specified & the threshhold
|
|
* got below half the pipesize. I.e., wait for bad news
|
|
* before we start updating, then update on both good
|
|
* and bad news.
|
|
*
|
|
* But we want to save the ssthresh even if no pipesize is
|
|
* specified explicitly in the route, because such
|
|
* connections still have an implicit pipesize specified
|
|
* by the global tcp_sendspace. In the absence of a reliable
|
|
* way to calculate the pipesize, it will have to do.
|
|
*/
|
|
i = tp->snd_ssthresh;
|
|
if (rt->rt_rmx.rmx_sendpipe != 0)
|
|
dosavessthresh = (i < rt->rt_rmx.rmx_sendpipe / 2);
|
|
else
|
|
dosavessthresh = (i < so->so_snd.sb_hiwat / 2);
|
|
if (((rt->rt_rmx.rmx_locks & RTV_SSTHRESH) == 0 &&
|
|
i != 0 && rt->rt_rmx.rmx_ssthresh != 0)
|
|
|| dosavessthresh) {
|
|
/*
|
|
* convert the limit from user data bytes to
|
|
* packets then to packet data bytes.
|
|
*/
|
|
i = (i + tp->t_maxseg / 2) / tp->t_maxseg;
|
|
if (i < 2)
|
|
i = 2;
|
|
i *= (u_long)(tp->t_maxseg +
|
|
#ifdef INET6
|
|
(isipv6 ? sizeof (struct ip6_hdr) +
|
|
sizeof (struct tcphdr) :
|
|
#endif
|
|
sizeof (struct tcpiphdr)
|
|
#ifdef INET6
|
|
)
|
|
#endif
|
|
);
|
|
if (rt->rt_rmx.rmx_ssthresh)
|
|
rt->rt_rmx.rmx_ssthresh =
|
|
(rt->rt_rmx.rmx_ssthresh + i) / 2;
|
|
else
|
|
rt->rt_rmx.rmx_ssthresh = i;
|
|
tcpstat.tcps_cachedssthresh++;
|
|
}
|
|
}
|
|
no_valid_rt:
|
|
/* free the reassembly queue, if any */
|
|
while((q = LIST_FIRST(&tp->t_segq)) != NULL) {
|
|
LIST_REMOVE(q, tqe_q);
|
|
m_freem(q->tqe_m);
|
|
FREE(q, M_TSEGQ);
|
|
}
|
|
inp->inp_ppcb = NULL;
|
|
soisdisconnected(so);
|
|
#ifdef INET6
|
|
if (INP_CHECK_SOCKAF(so, AF_INET6))
|
|
in6_pcbdetach(inp);
|
|
else
|
|
#endif /* INET6 */
|
|
in_pcbdetach(inp);
|
|
tcpstat.tcps_closed++;
|
|
return ((struct tcpcb *)0);
|
|
}
|
|
|
|
void
|
|
tcp_drain()
|
|
{
|
|
if (do_tcpdrain)
|
|
{
|
|
struct inpcb *inpb;
|
|
struct tcpcb *tcpb;
|
|
struct tseg_qent *te;
|
|
|
|
/*
|
|
* 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
|
|
* usefull.
|
|
*/
|
|
LIST_FOREACH(inpb, tcbinfo.listhead, inp_list) {
|
|
if ((tcpb = intotcpcb(inpb))) {
|
|
while ((te = LIST_FIRST(&tcpb->t_segq))
|
|
!= NULL) {
|
|
LIST_REMOVE(te, tqe_q);
|
|
m_freem(te->tqe_m);
|
|
FREE(te, M_TSEGQ);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* 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 void
|
|
tcp_notify(inp, error)
|
|
struct inpcb *inp;
|
|
int error;
|
|
{
|
|
struct tcpcb *tp = (struct tcpcb *)inp->inp_ppcb;
|
|
|
|
/*
|
|
* 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)) {
|
|
return;
|
|
} else if (tp->t_state < TCPS_ESTABLISHED && tp->t_rxtshift > 3 &&
|
|
tp->t_softerror)
|
|
tcp_drop(tp, error);
|
|
else
|
|
tp->t_softerror = error;
|
|
#if 0
|
|
wakeup((caddr_t) &so->so_timeo);
|
|
sorwakeup(so);
|
|
sowwakeup(so);
|
|
#endif
|
|
}
|
|
|
|
static int
|
|
tcp_pcblist(SYSCTL_HANDLER_ARGS)
|
|
{
|
|
int error, i, n, s;
|
|
struct inpcb *inp, **inp_list;
|
|
inp_gen_t gencnt;
|
|
struct xinpgen xig;
|
|
|
|
/*
|
|
* The process of preparing the TCB list is too time-consuming and
|
|
* resource-intensive to repeat twice on every request.
|
|
*/
|
|
if (req->oldptr == 0) {
|
|
n = tcbinfo.ipi_count;
|
|
req->oldidx = 2 * (sizeof xig)
|
|
+ (n + n/8) * sizeof(struct xtcpcb);
|
|
return 0;
|
|
}
|
|
|
|
if (req->newptr != 0)
|
|
return EPERM;
|
|
|
|
/*
|
|
* OK, now we're committed to doing something.
|
|
*/
|
|
s = splnet();
|
|
gencnt = tcbinfo.ipi_gencnt;
|
|
n = tcbinfo.ipi_count;
|
|
splx(s);
|
|
|
|
xig.xig_len = sizeof xig;
|
|
xig.xig_count = n;
|
|
xig.xig_gen = gencnt;
|
|
xig.xig_sogen = so_gencnt;
|
|
error = SYSCTL_OUT(req, &xig, sizeof xig);
|
|
if (error)
|
|
return error;
|
|
|
|
inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK);
|
|
if (inp_list == 0)
|
|
return ENOMEM;
|
|
|
|
s = splnet();
|
|
for (inp = LIST_FIRST(tcbinfo.listhead), i = 0; inp && i < n;
|
|
inp = LIST_NEXT(inp, inp_list)) {
|
|
if (inp->inp_gencnt <= gencnt) {
|
|
if (cr_canseesocket(req->td->td_ucred,
|
|
inp->inp_socket))
|
|
continue;
|
|
inp_list[i++] = inp;
|
|
}
|
|
}
|
|
splx(s);
|
|
n = i;
|
|
|
|
error = 0;
|
|
for (i = 0; i < n; i++) {
|
|
inp = inp_list[i];
|
|
if (inp->inp_gencnt <= gencnt) {
|
|
struct xtcpcb xt;
|
|
caddr_t inp_ppcb;
|
|
xt.xt_len = sizeof xt;
|
|
/* XXX should avoid extra copy */
|
|
bcopy(inp, &xt.xt_inp, sizeof *inp);
|
|
inp_ppcb = inp->inp_ppcb;
|
|
if (inp_ppcb != NULL)
|
|
bcopy(inp_ppcb, &xt.xt_tp, sizeof xt.xt_tp);
|
|
else
|
|
bzero((char *) &xt.xt_tp, sizeof xt.xt_tp);
|
|
if (inp->inp_socket)
|
|
sotoxsocket(inp->inp_socket, &xt.xt_socket);
|
|
error = SYSCTL_OUT(req, &xt, sizeof xt);
|
|
}
|
|
}
|
|
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.
|
|
*/
|
|
s = splnet();
|
|
xig.xig_gen = tcbinfo.ipi_gencnt;
|
|
xig.xig_sogen = so_gencnt;
|
|
xig.xig_count = tcbinfo.ipi_count;
|
|
splx(s);
|
|
error = SYSCTL_OUT(req, &xig, sizeof xig);
|
|
}
|
|
free(inp_list, M_TEMP);
|
|
return error;
|
|
}
|
|
|
|
SYSCTL_PROC(_net_inet_tcp, TCPCTL_PCBLIST, pcblist, CTLFLAG_RD, 0, 0,
|
|
tcp_pcblist, "S,xtcpcb", "List of active TCP connections");
|
|
|
|
static int
|
|
tcp_getcred(SYSCTL_HANDLER_ARGS)
|
|
{
|
|
struct xucred xuc;
|
|
struct sockaddr_in addrs[2];
|
|
struct inpcb *inp;
|
|
int error, s;
|
|
|
|
error = suser_cred(req->td->td_ucred, PRISON_ROOT);
|
|
if (error)
|
|
return (error);
|
|
error = SYSCTL_IN(req, addrs, sizeof(addrs));
|
|
if (error)
|
|
return (error);
|
|
s = splnet();
|
|
inp = in_pcblookup_hash(&tcbinfo, addrs[1].sin_addr, addrs[1].sin_port,
|
|
addrs[0].sin_addr, addrs[0].sin_port, 0, NULL);
|
|
if (inp == NULL || inp->inp_socket == NULL) {
|
|
error = ENOENT;
|
|
goto out;
|
|
}
|
|
error = cr_canseesocket(req->td->td_ucred, inp->inp_socket);
|
|
if (error)
|
|
goto out;
|
|
cru2x(inp->inp_socket->so_cred, &xuc);
|
|
error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
|
|
out:
|
|
splx(s);
|
|
return (error);
|
|
}
|
|
|
|
SYSCTL_PROC(_net_inet_tcp, OID_AUTO, getcred,
|
|
CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0,
|
|
tcp_getcred, "S,xucred", "Get the xucred of a TCP connection");
|
|
|
|
#ifdef INET6
|
|
static int
|
|
tcp6_getcred(SYSCTL_HANDLER_ARGS)
|
|
{
|
|
struct xucred xuc;
|
|
struct sockaddr_in6 addrs[2];
|
|
struct inpcb *inp;
|
|
int error, s, mapped = 0;
|
|
|
|
error = suser_cred(req->td->td_ucred, PRISON_ROOT);
|
|
if (error)
|
|
return (error);
|
|
error = SYSCTL_IN(req, addrs, sizeof(addrs));
|
|
if (error)
|
|
return (error);
|
|
if (IN6_IS_ADDR_V4MAPPED(&addrs[0].sin6_addr)) {
|
|
if (IN6_IS_ADDR_V4MAPPED(&addrs[1].sin6_addr))
|
|
mapped = 1;
|
|
else
|
|
return (EINVAL);
|
|
}
|
|
s = splnet();
|
|
if (mapped == 1)
|
|
inp = in_pcblookup_hash(&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,
|
|
0, NULL);
|
|
else
|
|
inp = in6_pcblookup_hash(&tcbinfo, &addrs[1].sin6_addr,
|
|
addrs[1].sin6_port,
|
|
&addrs[0].sin6_addr, addrs[0].sin6_port,
|
|
0, NULL);
|
|
if (inp == NULL || inp->inp_socket == NULL) {
|
|
error = ENOENT;
|
|
goto out;
|
|
}
|
|
error = cr_canseesocket(req->td->td_ucred, inp->inp_socket);
|
|
if (error)
|
|
goto out;
|
|
cru2x(inp->inp_socket->so_cred, &xuc);
|
|
error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
|
|
out:
|
|
splx(s);
|
|
return (error);
|
|
}
|
|
|
|
SYSCTL_PROC(_net_inet6_tcp6, OID_AUTO, getcred,
|
|
CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0,
|
|
tcp6_getcred, "S,xucred", "Get the xucred of a TCP6 connection");
|
|
#endif
|
|
|
|
|
|
void
|
|
tcp_ctlinput(cmd, sa, vip)
|
|
int cmd;
|
|
struct sockaddr *sa;
|
|
void *vip;
|
|
{
|
|
struct ip *ip = vip;
|
|
struct tcphdr *th;
|
|
struct in_addr faddr;
|
|
struct inpcb *inp;
|
|
struct tcpcb *tp;
|
|
void (*notify)(struct inpcb *, int) = tcp_notify;
|
|
tcp_seq icmp_seq;
|
|
int s;
|
|
|
|
faddr = ((struct sockaddr_in *)sa)->sin_addr;
|
|
if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY)
|
|
return;
|
|
|
|
if (cmd == PRC_QUENCH)
|
|
notify = tcp_quench;
|
|
else if (icmp_may_rst && (cmd == PRC_UNREACH_ADMIN_PROHIB ||
|
|
cmd == PRC_UNREACH_PORT) && ip)
|
|
notify = tcp_drop_syn_sent;
|
|
else if (cmd == PRC_MSGSIZE)
|
|
notify = tcp_mtudisc;
|
|
else if (PRC_IS_REDIRECT(cmd)) {
|
|
ip = 0;
|
|
notify = in_rtchange;
|
|
} else if (cmd == PRC_HOSTDEAD)
|
|
ip = 0;
|
|
else if ((unsigned)cmd > PRC_NCMDS || inetctlerrmap[cmd] == 0)
|
|
return;
|
|
if (ip) {
|
|
s = splnet();
|
|
th = (struct tcphdr *)((caddr_t)ip
|
|
+ (IP_VHL_HL(ip->ip_vhl) << 2));
|
|
inp = in_pcblookup_hash(&tcbinfo, faddr, th->th_dport,
|
|
ip->ip_src, th->th_sport, 0, NULL);
|
|
if (inp != NULL && inp->inp_socket != NULL) {
|
|
icmp_seq = htonl(th->th_seq);
|
|
tp = intotcpcb(inp);
|
|
if (SEQ_GEQ(icmp_seq, tp->snd_una) &&
|
|
SEQ_LT(icmp_seq, tp->snd_max))
|
|
(*notify)(inp, inetctlerrmap[cmd]);
|
|
} else {
|
|
struct in_conninfo inc;
|
|
|
|
inc.inc_fport = th->th_dport;
|
|
inc.inc_lport = th->th_sport;
|
|
inc.inc_faddr = faddr;
|
|
inc.inc_laddr = ip->ip_src;
|
|
#ifdef INET6
|
|
inc.inc_isipv6 = 0;
|
|
#endif
|
|
syncache_unreach(&inc, th);
|
|
}
|
|
splx(s);
|
|
} else
|
|
in_pcbnotifyall(&tcb, faddr, inetctlerrmap[cmd], notify);
|
|
}
|
|
|
|
#ifdef INET6
|
|
void
|
|
tcp6_ctlinput(cmd, sa, d)
|
|
int cmd;
|
|
struct sockaddr *sa;
|
|
void *d;
|
|
{
|
|
struct tcphdr th;
|
|
void (*notify)(struct inpcb *, int) = tcp_notify;
|
|
struct ip6_hdr *ip6;
|
|
struct mbuf *m;
|
|
struct ip6ctlparam *ip6cp = NULL;
|
|
const struct sockaddr_in6 *sa6_src = NULL;
|
|
int off;
|
|
struct tcp_portonly {
|
|
u_int16_t th_sport;
|
|
u_int16_t th_dport;
|
|
} *thp;
|
|
|
|
if (sa->sa_family != AF_INET6 ||
|
|
sa->sa_len != sizeof(struct sockaddr_in6))
|
|
return;
|
|
|
|
if (cmd == PRC_QUENCH)
|
|
notify = tcp_quench;
|
|
else if (cmd == PRC_MSGSIZE)
|
|
notify = tcp_mtudisc;
|
|
else if (!PRC_IS_REDIRECT(cmd) &&
|
|
((unsigned)cmd > PRC_NCMDS || inet6ctlerrmap[cmd] == 0))
|
|
return;
|
|
|
|
/* if the parameter is from icmp6, decode it. */
|
|
if (d != NULL) {
|
|
ip6cp = (struct ip6ctlparam *)d;
|
|
m = ip6cp->ip6c_m;
|
|
ip6 = ip6cp->ip6c_ip6;
|
|
off = ip6cp->ip6c_off;
|
|
sa6_src = ip6cp->ip6c_src;
|
|
} else {
|
|
m = NULL;
|
|
ip6 = NULL;
|
|
off = 0; /* fool gcc */
|
|
sa6_src = &sa6_any;
|
|
}
|
|
|
|
if (ip6) {
|
|
struct in_conninfo inc;
|
|
/*
|
|
* XXX: We assume that when IPV6 is non NULL,
|
|
* M and OFF are valid.
|
|
*/
|
|
|
|
/* check if we can safely examine src and dst ports */
|
|
if (m->m_pkthdr.len < off + sizeof(*thp))
|
|
return;
|
|
|
|
bzero(&th, sizeof(th));
|
|
m_copydata(m, off, sizeof(*thp), (caddr_t)&th);
|
|
|
|
in6_pcbnotify(&tcb, sa, th.th_dport,
|
|
(struct sockaddr *)ip6cp->ip6c_src,
|
|
th.th_sport, cmd, notify);
|
|
|
|
inc.inc_fport = th.th_dport;
|
|
inc.inc_lport = th.th_sport;
|
|
inc.inc6_faddr = ((struct sockaddr_in6 *)sa)->sin6_addr;
|
|
inc.inc6_laddr = ip6cp->ip6c_src->sin6_addr;
|
|
inc.inc_isipv6 = 1;
|
|
syncache_unreach(&inc, &th);
|
|
} else
|
|
in6_pcbnotify(&tcb, sa, 0, (const struct sockaddr *)sa6_src,
|
|
0, cmd, notify);
|
|
}
|
|
#endif /* INET6 */
|
|
|
|
|
|
/*
|
|
* 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 to generate sequence numbers.
|
|
*
|
|
* 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.
|
|
*
|
|
* 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.
|
|
*
|
|
*/
|
|
|
|
#define ISN_BYTES_PER_SECOND 1048576
|
|
|
|
u_char isn_secret[32];
|
|
int isn_last_reseed;
|
|
MD5_CTX isn_ctx;
|
|
|
|
tcp_seq
|
|
tcp_new_isn(tp)
|
|
struct tcpcb *tp;
|
|
{
|
|
u_int32_t md5_buffer[4];
|
|
tcp_seq new_isn;
|
|
|
|
/* Seed if this is the first use, reseed if requested. */
|
|
if ((isn_last_reseed == 0) || ((tcp_isn_reseed_interval > 0) &&
|
|
(((u_int)isn_last_reseed + (u_int)tcp_isn_reseed_interval*hz)
|
|
< (u_int)ticks))) {
|
|
read_random(&isn_secret, sizeof(isn_secret));
|
|
isn_last_reseed = ticks;
|
|
}
|
|
|
|
/* Compute the md5 hash and return the ISN. */
|
|
MD5Init(&isn_ctx);
|
|
MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_fport, sizeof(u_short));
|
|
MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_lport, sizeof(u_short));
|
|
#ifdef INET6
|
|
if ((tp->t_inpcb->inp_vflag & INP_IPV6) != 0) {
|
|
MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->in6p_faddr,
|
|
sizeof(struct in6_addr));
|
|
MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->in6p_laddr,
|
|
sizeof(struct in6_addr));
|
|
} else
|
|
#endif
|
|
{
|
|
MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_faddr,
|
|
sizeof(struct in_addr));
|
|
MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_laddr,
|
|
sizeof(struct in_addr));
|
|
}
|
|
MD5Update(&isn_ctx, (u_char *) &isn_secret, sizeof(isn_secret));
|
|
MD5Final((u_char *) &md5_buffer, &isn_ctx);
|
|
new_isn = (tcp_seq) md5_buffer[0];
|
|
new_isn += ticks * (ISN_BYTES_PER_SECOND / hz);
|
|
return new_isn;
|
|
}
|
|
|
|
/*
|
|
* When a source quench is received, close congestion window
|
|
* to one segment. We will gradually open it again as we proceed.
|
|
*/
|
|
void
|
|
tcp_quench(inp, errno)
|
|
struct inpcb *inp;
|
|
int errno;
|
|
{
|
|
struct tcpcb *tp = intotcpcb(inp);
|
|
|
|
if (tp)
|
|
tp->snd_cwnd = tp->t_maxseg;
|
|
}
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
void
|
|
tcp_drop_syn_sent(inp, errno)
|
|
struct inpcb *inp;
|
|
int errno;
|
|
{
|
|
struct tcpcb *tp = intotcpcb(inp);
|
|
|
|
if (tp && tp->t_state == TCPS_SYN_SENT)
|
|
tcp_drop(tp, errno);
|
|
}
|
|
|
|
/*
|
|
* When `need fragmentation' ICMP is received, update our idea of the MSS
|
|
* based on the new value in the route. 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.
|
|
*/
|
|
void
|
|
tcp_mtudisc(inp, errno)
|
|
struct inpcb *inp;
|
|
int errno;
|
|
{
|
|
struct tcpcb *tp = intotcpcb(inp);
|
|
struct rtentry *rt;
|
|
struct rmxp_tao *taop;
|
|
struct socket *so = inp->inp_socket;
|
|
int offered;
|
|
int mss;
|
|
#ifdef INET6
|
|
int isipv6 = (tp->t_inpcb->inp_vflag & INP_IPV6) != 0;
|
|
#endif /* INET6 */
|
|
|
|
if (tp) {
|
|
#ifdef INET6
|
|
if (isipv6)
|
|
rt = tcp_rtlookup6(&inp->inp_inc);
|
|
else
|
|
#endif /* INET6 */
|
|
rt = tcp_rtlookup(&inp->inp_inc);
|
|
if (!rt || !rt->rt_rmx.rmx_mtu) {
|
|
tp->t_maxopd = tp->t_maxseg =
|
|
#ifdef INET6
|
|
isipv6 ? tcp_v6mssdflt :
|
|
#endif /* INET6 */
|
|
tcp_mssdflt;
|
|
return;
|
|
}
|
|
taop = rmx_taop(rt->rt_rmx);
|
|
offered = taop->tao_mssopt;
|
|
mss = rt->rt_rmx.rmx_mtu -
|
|
#ifdef INET6
|
|
(isipv6 ?
|
|
sizeof(struct ip6_hdr) + sizeof(struct tcphdr) :
|
|
#endif /* INET6 */
|
|
sizeof(struct tcpiphdr)
|
|
#ifdef INET6
|
|
)
|
|
#endif /* INET6 */
|
|
;
|
|
|
|
if (offered)
|
|
mss = min(mss, offered);
|
|
/*
|
|
* XXX - The above conditional 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.
|
|
*/
|
|
if (tp->t_maxopd <= mss)
|
|
return;
|
|
tp->t_maxopd = mss;
|
|
|
|
if ((tp->t_flags & (TF_REQ_TSTMP|TF_NOOPT)) == TF_REQ_TSTMP &&
|
|
(tp->t_flags & TF_RCVD_TSTMP) == TF_RCVD_TSTMP)
|
|
mss -= TCPOLEN_TSTAMP_APPA;
|
|
if ((tp->t_flags & (TF_REQ_CC|TF_NOOPT)) == TF_REQ_CC &&
|
|
(tp->t_flags & TF_RCVD_CC) == TF_RCVD_CC)
|
|
mss -= TCPOLEN_CC_APPA;
|
|
#if (MCLBYTES & (MCLBYTES - 1)) == 0
|
|
if (mss > MCLBYTES)
|
|
mss &= ~(MCLBYTES-1);
|
|
#else
|
|
if (mss > MCLBYTES)
|
|
mss = mss / MCLBYTES * MCLBYTES;
|
|
#endif
|
|
if (so->so_snd.sb_hiwat < mss)
|
|
mss = so->so_snd.sb_hiwat;
|
|
|
|
tp->t_maxseg = mss;
|
|
|
|
tcpstat.tcps_mturesent++;
|
|
tp->t_rtttime = 0;
|
|
tp->snd_nxt = tp->snd_una;
|
|
tcp_output(tp);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Look-up the routing entry to the peer of this inpcb. If no route
|
|
* is found and it cannot be allocated the return NULL. This routine
|
|
* is called by TCP routines that access the rmx structure and by tcp_mss
|
|
* to get the interface MTU.
|
|
*/
|
|
struct rtentry *
|
|
tcp_rtlookup(inc)
|
|
struct in_conninfo *inc;
|
|
{
|
|
struct route *ro;
|
|
struct rtentry *rt;
|
|
|
|
ro = &inc->inc_route;
|
|
rt = ro->ro_rt;
|
|
if (rt == NULL || !(rt->rt_flags & RTF_UP)) {
|
|
/* No route yet, so try to acquire one */
|
|
if (inc->inc_faddr.s_addr != INADDR_ANY) {
|
|
ro->ro_dst.sa_family = AF_INET;
|
|
ro->ro_dst.sa_len = sizeof(struct sockaddr_in);
|
|
((struct sockaddr_in *) &ro->ro_dst)->sin_addr =
|
|
inc->inc_faddr;
|
|
rtalloc(ro);
|
|
rt = ro->ro_rt;
|
|
}
|
|
}
|
|
return rt;
|
|
}
|
|
|
|
#ifdef INET6
|
|
struct rtentry *
|
|
tcp_rtlookup6(inc)
|
|
struct in_conninfo *inc;
|
|
{
|
|
struct route_in6 *ro6;
|
|
struct rtentry *rt;
|
|
|
|
ro6 = &inc->inc6_route;
|
|
rt = ro6->ro_rt;
|
|
if (rt == NULL || !(rt->rt_flags & RTF_UP)) {
|
|
/* No route yet, so try to acquire one */
|
|
if (!IN6_IS_ADDR_UNSPECIFIED(&inc->inc6_faddr)) {
|
|
ro6->ro_dst.sin6_family = AF_INET6;
|
|
ro6->ro_dst.sin6_len = sizeof(struct sockaddr_in6);
|
|
ro6->ro_dst.sin6_addr = inc->inc6_faddr;
|
|
rtalloc((struct route *)ro6);
|
|
rt = ro6->ro_rt;
|
|
}
|
|
}
|
|
return rt;
|
|
}
|
|
#endif /* INET6 */
|
|
|
|
#ifdef IPSEC
|
|
/* compute ESP/AH header size for TCP, including outer IP header. */
|
|
size_t
|
|
ipsec_hdrsiz_tcp(tp)
|
|
struct tcpcb *tp;
|
|
{
|
|
struct inpcb *inp;
|
|
struct mbuf *m;
|
|
size_t hdrsiz;
|
|
struct ip *ip;
|
|
#ifdef INET6
|
|
struct ip6_hdr *ip6;
|
|
#endif /* INET6 */
|
|
struct tcphdr *th;
|
|
|
|
if ((tp == NULL) || ((inp = tp->t_inpcb) == NULL))
|
|
return 0;
|
|
MGETHDR(m, M_DONTWAIT, MT_DATA);
|
|
if (!m)
|
|
return 0;
|
|
|
|
#ifdef INET6
|
|
if ((inp->inp_vflag & INP_IPV6) != 0) {
|
|
ip6 = mtod(m, struct ip6_hdr *);
|
|
th = (struct tcphdr *)(ip6 + 1);
|
|
m->m_pkthdr.len = m->m_len =
|
|
sizeof(struct ip6_hdr) + sizeof(struct tcphdr);
|
|
tcp_fillheaders(tp, ip6, th);
|
|
hdrsiz = ipsec6_hdrsiz(m, IPSEC_DIR_OUTBOUND, inp);
|
|
} else
|
|
#endif /* INET6 */
|
|
{
|
|
ip = mtod(m, struct ip *);
|
|
th = (struct tcphdr *)(ip + 1);
|
|
m->m_pkthdr.len = m->m_len = sizeof(struct tcpiphdr);
|
|
tcp_fillheaders(tp, ip, th);
|
|
hdrsiz = ipsec4_hdrsiz(m, IPSEC_DIR_OUTBOUND, inp);
|
|
}
|
|
|
|
m_free(m);
|
|
return hdrsiz;
|
|
}
|
|
#endif /*IPSEC*/
|
|
|
|
/*
|
|
* Return a pointer to the cached information about the remote host.
|
|
* The cached information is stored in the protocol specific part of
|
|
* the route metrics.
|
|
*/
|
|
struct rmxp_tao *
|
|
tcp_gettaocache(inc)
|
|
struct in_conninfo *inc;
|
|
{
|
|
struct rtentry *rt;
|
|
|
|
#ifdef INET6
|
|
if (inc->inc_isipv6)
|
|
rt = tcp_rtlookup6(inc);
|
|
else
|
|
#endif /* INET6 */
|
|
rt = tcp_rtlookup(inc);
|
|
|
|
/* Make sure this is a host route and is up. */
|
|
if (rt == NULL ||
|
|
(rt->rt_flags & (RTF_UP|RTF_HOST)) != (RTF_UP|RTF_HOST))
|
|
return NULL;
|
|
|
|
return rmx_taop(rt->rt_rmx);
|
|
}
|
|
|
|
/*
|
|
* Clear all the TAO cache entries, called from tcp_init.
|
|
*
|
|
* XXX
|
|
* This routine is just an empty one, because we assume that the routing
|
|
* routing tables are initialized at the same time when TCP, so there is
|
|
* nothing in the cache left over.
|
|
*/
|
|
static void
|
|
tcp_cleartaocache()
|
|
{
|
|
}
|