diff options
Diffstat (limited to 'sys/netinet/tcp_subr.c')
| -rw-r--r-- | sys/netinet/tcp_subr.c | 1510 |
1 files changed, 1510 insertions, 0 deletions
diff --git a/sys/netinet/tcp_subr.c b/sys/netinet/tcp_subr.c new file mode 100644 index 0000000..f7800d2 --- /dev/null +++ b/sys/netinet/tcp_subr.c @@ -0,0 +1,1510 @@ +/* + * 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 struct inpcb *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; + + INP_INFO_LOCK_INIT(&tcbinfo, "tcp"); + 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. + */ + INP_INFO_RLOCK(&tcbinfo); + LIST_FOREACH(inpb, tcbinfo.listhead, inp_list) { + INP_LOCK(inpb); + 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); + } + } + INP_UNLOCK(inpb); + } + INP_INFO_RUNLOCK(&tcbinfo); + } +} + +/* + * Notify a tcp user of an asynchronous error; + * store error as soft error, but wake up user + * (for now, won't do anything until can select for soft error). + * + * Do not wake up user since there currently is no mechanism for + * reporting soft errors (yet - a kqueue filter may be added). + */ +static struct inpcb * +tcp_notify(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 inp; + } else if (tp->t_state < TCPS_ESTABLISHED && tp->t_rxtshift > 3 && + tp->t_softerror) { + tcp_drop(tp, error); + return (struct inpcb *)0; + } else { + tp->t_softerror = error; + return inp; + } +#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(); + INP_INFO_RLOCK(&tcbinfo); + gencnt = tcbinfo.ipi_gencnt; + n = tcbinfo.ipi_count; + INP_INFO_RUNLOCK(&tcbinfo); + 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(); + INP_INFO_RLOCK(&tcbinfo); + for (inp = LIST_FIRST(tcbinfo.listhead), i = 0; inp && i < n; + inp = LIST_NEXT(inp, inp_list)) { + INP_LOCK(inp); + if (inp->inp_gencnt <= gencnt && + cr_canseesocket(req->td->td_ucred, inp->inp_socket) == 0) + inp_list[i++] = inp; + INP_UNLOCK(inp); + } + INP_INFO_RUNLOCK(&tcbinfo); + splx(s); + n = i; + + error = 0; + for (i = 0; i < n; i++) { + inp = inp_list[i]; + INP_LOCK(inp); + 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); + } + INP_UNLOCK(inp); + } + 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(); + INP_INFO_RLOCK(&tcbinfo); + xig.xig_gen = tcbinfo.ipi_gencnt; + xig.xig_sogen = so_gencnt; + xig.xig_count = tcbinfo.ipi_count; + INP_INFO_RUNLOCK(&tcbinfo); + 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_INFO_RLOCK(&tcbinfo); + 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) { + error = ENOENT; + goto outunlocked; + } else { + INP_LOCK(inp); + if (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: + INP_UNLOCK(inp); +outunlocked: + INP_INFO_RUNLOCK(&tcbinfo); + 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(); + INP_INFO_RLOCK(&tcbinfo); + 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) { + error = ENOENT; + goto outunlocked; + } else { + INP_LOCK(inp); + if (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: + INP_UNLOCK(inp); +outunlocked: + INP_INFO_RUNLOCK(&tcbinfo); + 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; + struct inpcb *(*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_INFO_WLOCK(&tcbinfo); + inp = in_pcblookup_hash(&tcbinfo, faddr, th->th_dport, + ip->ip_src, th->th_sport, 0, NULL); + if (inp != NULL) { + INP_LOCK(inp); + if (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)) + inp = (*notify)(inp, inetctlerrmap[cmd]); + } + if (inp) + INP_UNLOCK(inp); + } 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); + } + INP_INFO_WUNLOCK(&tcbinfo); + splx(s); + } else + in_pcbnotifyall(&tcbinfo, faddr, inetctlerrmap[cmd], notify); +} + +#ifdef INET6 +void +tcp6_ctlinput(cmd, sa, d) + int cmd; + struct sockaddr *sa; + void *d; +{ + struct tcphdr th; + struct inpcb *(*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. + */ +struct inpcb * +tcp_quench(inp, errno) + struct inpcb *inp; + int errno; +{ + struct tcpcb *tp = intotcpcb(inp); + + if (tp) + tp->snd_cwnd = tp->t_maxseg; + return (inp); +} + +/* + * 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. + */ +struct inpcb * +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); + return (struct inpcb *)0; + } + return inp; +} + +/* + * 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. + */ +struct inpcb * +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 inp; + } + 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 inp; + 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); + } + return inp; +} + +/* + * 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() +{ +} |
