1 /* 2 * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)tcp_subr.c 8.2 (Berkeley) 5/24/95 34 * $FreeBSD$ 35 */ 36 37 #include "opt_compat.h" 38 #include "opt_inet6.h" 39 #include "opt_ipsec.h" 40 #include "opt_tcpdebug.h" 41 42 #include <sys/param.h> 43 #include <sys/systm.h> 44 #include <sys/callout.h> 45 #include <sys/kernel.h> 46 #include <sys/sysctl.h> 47 #include <sys/malloc.h> 48 #include <sys/mbuf.h> 49 #ifdef INET6 50 #include <sys/domain.h> 51 #endif 52 #include <sys/proc.h> 53 #include <sys/socket.h> 54 #include <sys/socketvar.h> 55 #include <sys/protosw.h> 56 57 #include <vm/vm_zone.h> 58 59 #include <net/route.h> 60 #include <net/if.h> 61 62 #define _IP_VHL 63 #include <netinet/in.h> 64 #include <netinet/in_systm.h> 65 #include <netinet/ip.h> 66 #ifdef INET6 67 #include <netinet/ip6.h> 68 #endif 69 #include <netinet/in_pcb.h> 70 #ifdef INET6 71 #include <netinet6/in6_pcb.h> 72 #endif 73 #include <netinet/in_var.h> 74 #include <netinet/ip_var.h> 75 #ifdef INET6 76 #include <netinet6/ip6_var.h> 77 #endif 78 #include <netinet/tcp.h> 79 #include <netinet/tcp_fsm.h> 80 #include <netinet/tcp_seq.h> 81 #include <netinet/tcp_timer.h> 82 #include <netinet/tcp_var.h> 83 #ifdef INET6 84 #include <netinet6/tcp6_var.h> 85 #endif 86 #include <netinet/tcpip.h> 87 #ifdef TCPDEBUG 88 #include <netinet/tcp_debug.h> 89 #endif 90 #include <netinet6/ip6protosw.h> 91 92 #ifdef IPSEC 93 #include <netinet6/ipsec.h> 94 #ifdef INET6 95 #include <netinet6/ipsec6.h> 96 #endif 97 #endif /*IPSEC*/ 98 99 #include <machine/in_cksum.h> 100 101 int tcp_mssdflt = TCP_MSS; 102 SYSCTL_INT(_net_inet_tcp, TCPCTL_MSSDFLT, mssdflt, CTLFLAG_RW, 103 &tcp_mssdflt , 0, "Default TCP Maximum Segment Size"); 104 105 #ifdef INET6 106 int tcp_v6mssdflt = TCP6_MSS; 107 SYSCTL_INT(_net_inet_tcp, TCPCTL_V6MSSDFLT, v6mssdflt, 108 CTLFLAG_RW, &tcp_v6mssdflt , 0, 109 "Default TCP Maximum Segment Size for IPv6"); 110 #endif 111 112 #if 0 113 static int tcp_rttdflt = TCPTV_SRTTDFLT / PR_SLOWHZ; 114 SYSCTL_INT(_net_inet_tcp, TCPCTL_RTTDFLT, rttdflt, CTLFLAG_RW, 115 &tcp_rttdflt , 0, "Default maximum TCP Round Trip Time"); 116 #endif 117 118 static int tcp_do_rfc1323 = 1; 119 SYSCTL_INT(_net_inet_tcp, TCPCTL_DO_RFC1323, rfc1323, CTLFLAG_RW, 120 &tcp_do_rfc1323 , 0, "Enable rfc1323 (high performance TCP) extensions"); 121 122 static int tcp_do_rfc1644 = 0; 123 SYSCTL_INT(_net_inet_tcp, TCPCTL_DO_RFC1644, rfc1644, CTLFLAG_RW, 124 &tcp_do_rfc1644 , 0, "Enable rfc1644 (TTCP) extensions"); 125 126 static int tcp_tcbhashsize = 0; 127 SYSCTL_INT(_net_inet_tcp, OID_AUTO, tcbhashsize, CTLFLAG_RD, 128 &tcp_tcbhashsize, 0, "Size of TCP control-block hashtable"); 129 130 static int do_tcpdrain = 1; 131 SYSCTL_INT(_net_inet_tcp, OID_AUTO, do_tcpdrain, CTLFLAG_RW, &do_tcpdrain, 0, 132 "Enable tcp_drain routine for extra help when low on mbufs"); 133 134 SYSCTL_INT(_net_inet_tcp, OID_AUTO, pcbcount, CTLFLAG_RD, 135 &tcbinfo.ipi_count, 0, "Number of active PCBs"); 136 137 static void tcp_cleartaocache __P((void)); 138 static void tcp_notify __P((struct inpcb *, int)); 139 140 /* 141 * Target size of TCP PCB hash tables. Must be a power of two. 142 * 143 * Note that this can be overridden by the kernel environment 144 * variable net.inet.tcp.tcbhashsize 145 */ 146 #ifndef TCBHASHSIZE 147 #define TCBHASHSIZE 512 148 #endif 149 150 /* 151 * This is the actual shape of what we allocate using the zone 152 * allocator. Doing it this way allows us to protect both structures 153 * using the same generation count, and also eliminates the overhead 154 * of allocating tcpcbs separately. By hiding the structure here, 155 * we avoid changing most of the rest of the code (although it needs 156 * to be changed, eventually, for greater efficiency). 157 */ 158 #define ALIGNMENT 32 159 #define ALIGNM1 (ALIGNMENT - 1) 160 struct inp_tp { 161 union { 162 struct inpcb inp; 163 char align[(sizeof(struct inpcb) + ALIGNM1) & ~ALIGNM1]; 164 } inp_tp_u; 165 struct tcpcb tcb; 166 struct callout inp_tp_rexmt, inp_tp_persist, inp_tp_keep, inp_tp_2msl; 167 struct callout inp_tp_delack; 168 }; 169 #undef ALIGNMENT 170 #undef ALIGNM1 171 172 /* 173 * Tcp initialization 174 */ 175 void 176 tcp_init() 177 { 178 int hashsize; 179 180 tcp_iss = arc4random(); /* wrong, but better than a constant */ 181 tcp_ccgen = 1; 182 tcp_cleartaocache(); 183 184 tcp_delacktime = TCPTV_DELACK; 185 tcp_keepinit = TCPTV_KEEP_INIT; 186 tcp_keepidle = TCPTV_KEEP_IDLE; 187 tcp_keepintvl = TCPTV_KEEPINTVL; 188 tcp_maxpersistidle = TCPTV_KEEP_IDLE; 189 tcp_msl = TCPTV_MSL; 190 191 LIST_INIT(&tcb); 192 tcbinfo.listhead = &tcb; 193 TUNABLE_INT_FETCH("net.inet.tcp.tcbhashsize", TCBHASHSIZE, hashsize); 194 if (!powerof2(hashsize)) { 195 printf("WARNING: TCB hash size not a power of 2\n"); 196 hashsize = 512; /* safe default */ 197 } 198 tcp_tcbhashsize = hashsize; 199 tcbinfo.hashbase = hashinit(hashsize, M_PCB, &tcbinfo.hashmask); 200 tcbinfo.porthashbase = hashinit(hashsize, M_PCB, 201 &tcbinfo.porthashmask); 202 tcbinfo.ipi_zone = zinit("tcpcb", sizeof(struct inp_tp), maxsockets, 203 ZONE_INTERRUPT, 0); 204 #ifdef INET6 205 #define TCP_MINPROTOHDR (sizeof(struct ip6_hdr) + sizeof(struct tcphdr)) 206 #else /* INET6 */ 207 #define TCP_MINPROTOHDR (sizeof(struct tcpiphdr)) 208 #endif /* INET6 */ 209 if (max_protohdr < TCP_MINPROTOHDR) 210 max_protohdr = TCP_MINPROTOHDR; 211 if (max_linkhdr + TCP_MINPROTOHDR > MHLEN) 212 panic("tcp_init"); 213 #undef TCP_MINPROTOHDR 214 } 215 216 /* 217 * Create template to be used to send tcp packets on a connection. 218 * Call after host entry created, allocates an mbuf and fills 219 * in a skeletal tcp/ip header, minimizing the amount of work 220 * necessary when the connection is used. 221 */ 222 struct tcptemp * 223 tcp_template(tp) 224 struct tcpcb *tp; 225 { 226 register struct inpcb *inp = tp->t_inpcb; 227 register struct mbuf *m; 228 register struct tcptemp *n; 229 230 if ((n = tp->t_template) == 0) { 231 m = m_get(M_DONTWAIT, MT_HEADER); 232 if (m == NULL) 233 return (0); 234 m->m_len = sizeof (struct tcptemp); 235 n = mtod(m, struct tcptemp *); 236 } 237 #ifdef INET6 238 if ((inp->inp_vflag & INP_IPV6) != 0) { 239 register struct ip6_hdr *ip6; 240 241 ip6 = (struct ip6_hdr *)n->tt_ipgen; 242 ip6->ip6_flow = (ip6->ip6_flow & ~IPV6_FLOWINFO_MASK) | 243 (inp->in6p_flowinfo & IPV6_FLOWINFO_MASK); 244 ip6->ip6_vfc = (ip6->ip6_vfc & ~IPV6_VERSION_MASK) | 245 (IPV6_VERSION & IPV6_VERSION_MASK); 246 ip6->ip6_nxt = IPPROTO_TCP; 247 ip6->ip6_plen = sizeof(struct tcphdr); 248 ip6->ip6_src = inp->in6p_laddr; 249 ip6->ip6_dst = inp->in6p_faddr; 250 n->tt_t.th_sum = 0; 251 } else 252 #endif 253 { 254 struct ip *ip = (struct ip *)n->tt_ipgen; 255 256 bzero(ip, sizeof(struct ip)); /* XXX overkill? */ 257 ip->ip_vhl = IP_VHL_BORING; 258 ip->ip_p = IPPROTO_TCP; 259 ip->ip_src = inp->inp_laddr; 260 ip->ip_dst = inp->inp_faddr; 261 n->tt_t.th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, 262 htons(sizeof(struct tcphdr) + IPPROTO_TCP)); 263 } 264 n->tt_t.th_sport = inp->inp_lport; 265 n->tt_t.th_dport = inp->inp_fport; 266 n->tt_t.th_seq = 0; 267 n->tt_t.th_ack = 0; 268 n->tt_t.th_x2 = 0; 269 n->tt_t.th_off = 5; 270 n->tt_t.th_flags = 0; 271 n->tt_t.th_win = 0; 272 n->tt_t.th_urp = 0; 273 return (n); 274 } 275 276 /* 277 * Send a single message to the TCP at address specified by 278 * the given TCP/IP header. If m == 0, then we make a copy 279 * of the tcpiphdr at ti and send directly to the addressed host. 280 * This is used to force keep alive messages out using the TCP 281 * template for a connection tp->t_template. If flags are given 282 * then we send a message back to the TCP which originated the 283 * segment ti, and discard the mbuf containing it and any other 284 * attached mbufs. 285 * 286 * In any case the ack and sequence number of the transmitted 287 * segment are as specified by the parameters. 288 * 289 * NOTE: If m != NULL, then ti must point to *inside* the mbuf. 290 */ 291 void 292 tcp_respond(tp, ipgen, th, m, ack, seq, flags) 293 struct tcpcb *tp; 294 void *ipgen; 295 register struct tcphdr *th; 296 register struct mbuf *m; 297 tcp_seq ack, seq; 298 int flags; 299 { 300 register int tlen; 301 int win = 0; 302 struct route *ro = 0; 303 struct route sro; 304 struct ip *ip; 305 struct tcphdr *nth; 306 #ifdef INET6 307 struct route_in6 *ro6 = 0; 308 struct route_in6 sro6; 309 struct ip6_hdr *ip6; 310 int isipv6; 311 #endif /* INET6 */ 312 int ipflags = 0; 313 314 #ifdef INET6 315 isipv6 = IP_VHL_V(((struct ip *)ipgen)->ip_vhl) == 6; 316 ip6 = ipgen; 317 #endif /* INET6 */ 318 ip = ipgen; 319 320 if (tp) { 321 if (!(flags & TH_RST)) { 322 win = sbspace(&tp->t_inpcb->inp_socket->so_rcv); 323 if (win > (long)TCP_MAXWIN << tp->rcv_scale) 324 win = (long)TCP_MAXWIN << tp->rcv_scale; 325 } 326 #ifdef INET6 327 if (isipv6) 328 ro6 = &tp->t_inpcb->in6p_route; 329 else 330 #endif /* INET6 */ 331 ro = &tp->t_inpcb->inp_route; 332 } else { 333 #ifdef INET6 334 if (isipv6) { 335 ro6 = &sro6; 336 bzero(ro6, sizeof *ro6); 337 } else 338 #endif /* INET6 */ 339 { 340 ro = &sro; 341 bzero(ro, sizeof *ro); 342 } 343 } 344 if (m == 0) { 345 m = m_gethdr(M_DONTWAIT, MT_HEADER); 346 if (m == NULL) 347 return; 348 #ifdef TCP_COMPAT_42 349 tlen = 1; 350 #else 351 tlen = 0; 352 #endif 353 m->m_data += max_linkhdr; 354 #ifdef INET6 355 if (isipv6) { 356 bcopy((caddr_t)ip6, mtod(m, caddr_t), 357 sizeof(struct ip6_hdr)); 358 ip6 = mtod(m, struct ip6_hdr *); 359 nth = (struct tcphdr *)(ip6 + 1); 360 } else 361 #endif /* INET6 */ 362 { 363 bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip)); 364 ip = mtod(m, struct ip *); 365 nth = (struct tcphdr *)(ip + 1); 366 } 367 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr)); 368 flags = TH_ACK; 369 } else { 370 m_freem(m->m_next); 371 m->m_next = 0; 372 m->m_data = (caddr_t)ipgen; 373 /* m_len is set later */ 374 tlen = 0; 375 #define xchg(a,b,type) { type t; t=a; a=b; b=t; } 376 #ifdef INET6 377 if (isipv6) { 378 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); 379 nth = (struct tcphdr *)(ip6 + 1); 380 } else 381 #endif /* INET6 */ 382 { 383 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, n_long); 384 nth = (struct tcphdr *)(ip + 1); 385 } 386 if (th != nth) { 387 /* 388 * this is usually a case when an extension header 389 * exists between the IPv6 header and the 390 * TCP header. 391 */ 392 nth->th_sport = th->th_sport; 393 nth->th_dport = th->th_dport; 394 } 395 xchg(nth->th_dport, nth->th_sport, n_short); 396 #undef xchg 397 } 398 #ifdef INET6 399 if (isipv6) { 400 ip6->ip6_plen = htons((u_short)(sizeof (struct tcphdr) + 401 tlen)); 402 tlen += sizeof (struct ip6_hdr) + sizeof (struct tcphdr); 403 } else 404 #endif 405 { 406 tlen += sizeof (struct tcpiphdr); 407 ip->ip_len = tlen; 408 ip->ip_ttl = ip_defttl; 409 } 410 m->m_len = tlen; 411 m->m_pkthdr.len = tlen; 412 m->m_pkthdr.rcvif = (struct ifnet *) 0; 413 nth->th_seq = htonl(seq); 414 nth->th_ack = htonl(ack); 415 nth->th_x2 = 0; 416 nth->th_off = sizeof (struct tcphdr) >> 2; 417 nth->th_flags = flags; 418 if (tp) 419 nth->th_win = htons((u_short) (win >> tp->rcv_scale)); 420 else 421 nth->th_win = htons((u_short)win); 422 nth->th_urp = 0; 423 #ifdef INET6 424 if (isipv6) { 425 nth->th_sum = 0; 426 nth->th_sum = in6_cksum(m, IPPROTO_TCP, 427 sizeof(struct ip6_hdr), 428 tlen - sizeof(struct ip6_hdr)); 429 ip6->ip6_hlim = in6_selecthlim(tp ? tp->t_inpcb : NULL, 430 ro6 && ro6->ro_rt ? 431 ro6->ro_rt->rt_ifp : 432 NULL); 433 } else 434 #endif /* INET6 */ 435 { 436 nth->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, 437 htons((u_short)(tlen - sizeof(struct ip) + ip->ip_p))); 438 m->m_pkthdr.csum_flags = CSUM_TCP; 439 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); 440 } 441 #ifdef TCPDEBUG 442 if (tp == NULL || (tp->t_inpcb->inp_socket->so_options & SO_DEBUG)) 443 tcp_trace(TA_OUTPUT, 0, tp, mtod(m, void *), th, 0); 444 #endif 445 #ifdef IPSEC 446 ipsec_setsocket(m, tp ? tp->t_inpcb->inp_socket : NULL); 447 #endif 448 #ifdef INET6 449 if (isipv6) { 450 (void)ip6_output(m, NULL, ro6, ipflags, NULL, NULL); 451 if (ro6 == &sro6 && ro6->ro_rt) { 452 RTFREE(ro6->ro_rt); 453 ro6->ro_rt = NULL; 454 } 455 } else 456 #endif /* INET6 */ 457 { 458 (void) ip_output(m, NULL, ro, ipflags, NULL); 459 if (ro == &sro && ro->ro_rt) { 460 RTFREE(ro->ro_rt); 461 ro->ro_rt = NULL; 462 } 463 } 464 } 465 466 /* 467 * Create a new TCP control block, making an 468 * empty reassembly queue and hooking it to the argument 469 * protocol control block. The `inp' parameter must have 470 * come from the zone allocator set up in tcp_init(). 471 */ 472 struct tcpcb * 473 tcp_newtcpcb(inp) 474 struct inpcb *inp; 475 { 476 struct inp_tp *it; 477 register struct tcpcb *tp; 478 #ifdef INET6 479 int isipv6 = (inp->inp_vflag & INP_IPV6) != 0; 480 #endif /* INET6 */ 481 482 it = (struct inp_tp *)inp; 483 tp = &it->tcb; 484 bzero((char *) tp, sizeof(struct tcpcb)); 485 LIST_INIT(&tp->t_segq); 486 tp->t_maxseg = tp->t_maxopd = 487 #ifdef INET6 488 isipv6 ? tcp_v6mssdflt : 489 #endif /* INET6 */ 490 tcp_mssdflt; 491 492 /* Set up our timeouts. */ 493 callout_init(tp->tt_rexmt = &it->inp_tp_rexmt); 494 callout_init(tp->tt_persist = &it->inp_tp_persist); 495 callout_init(tp->tt_keep = &it->inp_tp_keep); 496 callout_init(tp->tt_2msl = &it->inp_tp_2msl); 497 callout_init(tp->tt_delack = &it->inp_tp_delack); 498 499 if (tcp_do_rfc1323) 500 tp->t_flags = (TF_REQ_SCALE|TF_REQ_TSTMP); 501 if (tcp_do_rfc1644) 502 tp->t_flags |= TF_REQ_CC; 503 tp->t_inpcb = inp; /* XXX */ 504 /* 505 * Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no 506 * rtt estimate. Set rttvar so that srtt + 4 * rttvar gives 507 * reasonable initial retransmit time. 508 */ 509 tp->t_srtt = TCPTV_SRTTBASE; 510 tp->t_rttvar = ((TCPTV_RTOBASE - TCPTV_SRTTBASE) << TCP_RTTVAR_SHIFT) / 4; 511 tp->t_rttmin = TCPTV_MIN; 512 tp->t_rxtcur = TCPTV_RTOBASE; 513 tp->snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT; 514 tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT; 515 tp->t_rcvtime = ticks; 516 /* 517 * IPv4 TTL initialization is necessary for an IPv6 socket as well, 518 * because the socket may be bound to an IPv6 wildcard address, 519 * which may match an IPv4-mapped IPv6 address. 520 */ 521 inp->inp_ip_ttl = ip_defttl; 522 inp->inp_ppcb = (caddr_t)tp; 523 return (tp); /* XXX */ 524 } 525 526 /* 527 * Drop a TCP connection, reporting 528 * the specified error. If connection is synchronized, 529 * then send a RST to peer. 530 */ 531 struct tcpcb * 532 tcp_drop(tp, errno) 533 register struct tcpcb *tp; 534 int errno; 535 { 536 struct socket *so = tp->t_inpcb->inp_socket; 537 538 if (TCPS_HAVERCVDSYN(tp->t_state)) { 539 tp->t_state = TCPS_CLOSED; 540 (void) tcp_output(tp); 541 tcpstat.tcps_drops++; 542 } else 543 tcpstat.tcps_conndrops++; 544 if (errno == ETIMEDOUT && tp->t_softerror) 545 errno = tp->t_softerror; 546 so->so_error = errno; 547 return (tcp_close(tp)); 548 } 549 550 /* 551 * Close a TCP control block: 552 * discard all space held by the tcp 553 * discard internet protocol block 554 * wake up any sleepers 555 */ 556 struct tcpcb * 557 tcp_close(tp) 558 register struct tcpcb *tp; 559 { 560 register struct tseg_qent *q; 561 struct inpcb *inp = tp->t_inpcb; 562 struct socket *so = inp->inp_socket; 563 #ifdef INET6 564 int isipv6 = (inp->inp_vflag & INP_IPV6) != 0; 565 #endif /* INET6 */ 566 register struct rtentry *rt; 567 int dosavessthresh; 568 569 /* 570 * Make sure that all of our timers are stopped before we 571 * delete the PCB. 572 */ 573 callout_stop(tp->tt_rexmt); 574 callout_stop(tp->tt_persist); 575 callout_stop(tp->tt_keep); 576 callout_stop(tp->tt_2msl); 577 callout_stop(tp->tt_delack); 578 579 /* 580 * If we got enough samples through the srtt filter, 581 * save the rtt and rttvar in the routing entry. 582 * 'Enough' is arbitrarily defined as the 16 samples. 583 * 16 samples is enough for the srtt filter to converge 584 * to within 5% of the correct value; fewer samples and 585 * we could save a very bogus rtt. 586 * 587 * Don't update the default route's characteristics and don't 588 * update anything that the user "locked". 589 */ 590 if (tp->t_rttupdated >= 16) { 591 register u_long i = 0; 592 #ifdef INET6 593 if (isipv6) { 594 struct sockaddr_in6 *sin6; 595 596 if ((rt = inp->in6p_route.ro_rt) == NULL) 597 goto no_valid_rt; 598 sin6 = (struct sockaddr_in6 *)rt_key(rt); 599 if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) 600 goto no_valid_rt; 601 } 602 else 603 #endif /* INET6 */ 604 if ((rt = inp->inp_route.ro_rt) == NULL || 605 ((struct sockaddr_in *)rt_key(rt))->sin_addr.s_addr 606 == INADDR_ANY) 607 goto no_valid_rt; 608 609 if ((rt->rt_rmx.rmx_locks & RTV_RTT) == 0) { 610 i = tp->t_srtt * 611 (RTM_RTTUNIT / (hz * TCP_RTT_SCALE)); 612 if (rt->rt_rmx.rmx_rtt && i) 613 /* 614 * filter this update to half the old & half 615 * the new values, converting scale. 616 * See route.h and tcp_var.h for a 617 * description of the scaling constants. 618 */ 619 rt->rt_rmx.rmx_rtt = 620 (rt->rt_rmx.rmx_rtt + i) / 2; 621 else 622 rt->rt_rmx.rmx_rtt = i; 623 tcpstat.tcps_cachedrtt++; 624 } 625 if ((rt->rt_rmx.rmx_locks & RTV_RTTVAR) == 0) { 626 i = tp->t_rttvar * 627 (RTM_RTTUNIT / (hz * TCP_RTTVAR_SCALE)); 628 if (rt->rt_rmx.rmx_rttvar && i) 629 rt->rt_rmx.rmx_rttvar = 630 (rt->rt_rmx.rmx_rttvar + i) / 2; 631 else 632 rt->rt_rmx.rmx_rttvar = i; 633 tcpstat.tcps_cachedrttvar++; 634 } 635 /* 636 * The old comment here said: 637 * update the pipelimit (ssthresh) if it has been updated 638 * already or if a pipesize was specified & the threshhold 639 * got below half the pipesize. I.e., wait for bad news 640 * before we start updating, then update on both good 641 * and bad news. 642 * 643 * But we want to save the ssthresh even if no pipesize is 644 * specified explicitly in the route, because such 645 * connections still have an implicit pipesize specified 646 * by the global tcp_sendspace. In the absence of a reliable 647 * way to calculate the pipesize, it will have to do. 648 */ 649 i = tp->snd_ssthresh; 650 if (rt->rt_rmx.rmx_sendpipe != 0) 651 dosavessthresh = (i < rt->rt_rmx.rmx_sendpipe / 2); 652 else 653 dosavessthresh = (i < so->so_snd.sb_hiwat / 2); 654 if (((rt->rt_rmx.rmx_locks & RTV_SSTHRESH) == 0 && 655 i != 0 && rt->rt_rmx.rmx_ssthresh != 0) 656 || dosavessthresh) { 657 /* 658 * convert the limit from user data bytes to 659 * packets then to packet data bytes. 660 */ 661 i = (i + tp->t_maxseg / 2) / tp->t_maxseg; 662 if (i < 2) 663 i = 2; 664 i *= (u_long)(tp->t_maxseg + 665 #ifdef INET6 666 (isipv6 ? sizeof (struct ip6_hdr) + 667 sizeof (struct tcphdr) : 668 #endif 669 sizeof (struct tcpiphdr) 670 #ifdef INET6 671 ) 672 #endif 673 ); 674 if (rt->rt_rmx.rmx_ssthresh) 675 rt->rt_rmx.rmx_ssthresh = 676 (rt->rt_rmx.rmx_ssthresh + i) / 2; 677 else 678 rt->rt_rmx.rmx_ssthresh = i; 679 tcpstat.tcps_cachedssthresh++; 680 } 681 } 682 rt = inp->inp_route.ro_rt; 683 if (rt) { 684 /* 685 * mark route for deletion if no information is 686 * cached. 687 */ 688 if ((tp->t_flags & TF_LQ_OVERFLOW) && 689 ((rt->rt_rmx.rmx_locks & RTV_RTT) == 0)){ 690 if (rt->rt_rmx.rmx_rtt == 0) 691 rt->rt_flags |= RTF_DELCLONE; 692 } 693 } 694 no_valid_rt: 695 /* free the reassembly queue, if any */ 696 while((q = LIST_FIRST(&tp->t_segq)) != NULL) { 697 LIST_REMOVE(q, tqe_q); 698 m_freem(q->tqe_m); 699 FREE(q, M_TSEGQ); 700 } 701 if (tp->t_template) 702 (void) m_free(dtom(tp->t_template)); 703 inp->inp_ppcb = NULL; 704 soisdisconnected(so); 705 #ifdef INET6 706 if (INP_CHECK_SOCKAF(so, AF_INET6)) 707 in6_pcbdetach(inp); 708 else 709 #endif /* INET6 */ 710 in_pcbdetach(inp); 711 tcpstat.tcps_closed++; 712 return ((struct tcpcb *)0); 713 } 714 715 void 716 tcp_drain() 717 { 718 if (do_tcpdrain) 719 { 720 struct inpcb *inpb; 721 struct tcpcb *tcpb; 722 struct tseg_qent *te; 723 724 /* 725 * Walk the tcpbs, if existing, and flush the reassembly queue, 726 * if there is one... 727 * XXX: The "Net/3" implementation doesn't imply that the TCP 728 * reassembly queue should be flushed, but in a situation 729 * where we're really low on mbufs, this is potentially 730 * usefull. 731 */ 732 for (inpb = tcbinfo.listhead->lh_first; inpb; 733 inpb = inpb->inp_list.le_next) { 734 if ((tcpb = intotcpcb(inpb))) { 735 while ((te = LIST_FIRST(&tcpb->t_segq)) 736 != NULL) { 737 LIST_REMOVE(te, tqe_q); 738 m_freem(te->tqe_m); 739 FREE(te, M_TSEGQ); 740 } 741 } 742 } 743 744 } 745 } 746 747 /* 748 * Notify a tcp user of an asynchronous error; 749 * store error as soft error, but wake up user 750 * (for now, won't do anything until can select for soft error). 751 */ 752 static void 753 tcp_notify(inp, error) 754 struct inpcb *inp; 755 int error; 756 { 757 register struct tcpcb *tp = (struct tcpcb *)inp->inp_ppcb; 758 register struct socket *so = inp->inp_socket; 759 760 /* 761 * Ignore some errors if we are hooked up. 762 * If connection hasn't completed, has retransmitted several times, 763 * and receives a second error, give up now. This is better 764 * than waiting a long time to establish a connection that 765 * can never complete. 766 */ 767 if (tp->t_state == TCPS_ESTABLISHED && 768 (error == EHOSTUNREACH || error == ENETUNREACH || 769 error == EHOSTDOWN)) { 770 return; 771 } else if (tp->t_state < TCPS_ESTABLISHED && tp->t_rxtshift > 3 && 772 tp->t_softerror) 773 so->so_error = error; 774 else 775 tp->t_softerror = error; 776 wakeup((caddr_t) &so->so_timeo); 777 sorwakeup(so); 778 sowwakeup(so); 779 } 780 781 static int 782 tcp_pcblist(SYSCTL_HANDLER_ARGS) 783 { 784 int error, i, n, s; 785 struct inpcb *inp, **inp_list; 786 inp_gen_t gencnt; 787 struct xinpgen xig; 788 789 /* 790 * The process of preparing the TCB list is too time-consuming and 791 * resource-intensive to repeat twice on every request. 792 */ 793 if (req->oldptr == 0) { 794 n = tcbinfo.ipi_count; 795 req->oldidx = 2 * (sizeof xig) 796 + (n + n/8) * sizeof(struct xtcpcb); 797 return 0; 798 } 799 800 if (req->newptr != 0) 801 return EPERM; 802 803 /* 804 * OK, now we're committed to doing something. 805 */ 806 s = splnet(); 807 gencnt = tcbinfo.ipi_gencnt; 808 n = tcbinfo.ipi_count; 809 splx(s); 810 811 xig.xig_len = sizeof xig; 812 xig.xig_count = n; 813 xig.xig_gen = gencnt; 814 xig.xig_sogen = so_gencnt; 815 error = SYSCTL_OUT(req, &xig, sizeof xig); 816 if (error) 817 return error; 818 819 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK); 820 if (inp_list == 0) 821 return ENOMEM; 822 823 s = splnet(); 824 for (inp = tcbinfo.listhead->lh_first, i = 0; inp && i < n; 825 inp = inp->inp_list.le_next) { 826 if (inp->inp_gencnt <= gencnt && !prison_xinpcb(req->p, inp)) 827 inp_list[i++] = inp; 828 } 829 splx(s); 830 n = i; 831 832 error = 0; 833 for (i = 0; i < n; i++) { 834 inp = inp_list[i]; 835 if (inp->inp_gencnt <= gencnt) { 836 struct xtcpcb xt; 837 caddr_t inp_ppcb; 838 xt.xt_len = sizeof xt; 839 /* XXX should avoid extra copy */ 840 bcopy(inp, &xt.xt_inp, sizeof *inp); 841 inp_ppcb = inp->inp_ppcb; 842 if (inp_ppcb != NULL) 843 bcopy(inp_ppcb, &xt.xt_tp, sizeof xt.xt_tp); 844 else 845 bzero((char *) &xt.xt_tp, sizeof xt.xt_tp); 846 if (inp->inp_socket) 847 sotoxsocket(inp->inp_socket, &xt.xt_socket); 848 error = SYSCTL_OUT(req, &xt, sizeof xt); 849 } 850 } 851 if (!error) { 852 /* 853 * Give the user an updated idea of our state. 854 * If the generation differs from what we told 855 * her before, she knows that something happened 856 * while we were processing this request, and it 857 * might be necessary to retry. 858 */ 859 s = splnet(); 860 xig.xig_gen = tcbinfo.ipi_gencnt; 861 xig.xig_sogen = so_gencnt; 862 xig.xig_count = tcbinfo.ipi_count; 863 splx(s); 864 error = SYSCTL_OUT(req, &xig, sizeof xig); 865 } 866 free(inp_list, M_TEMP); 867 return error; 868 } 869 870 SYSCTL_PROC(_net_inet_tcp, TCPCTL_PCBLIST, pcblist, CTLFLAG_RD, 0, 0, 871 tcp_pcblist, "S,xtcpcb", "List of active TCP connections"); 872 873 static int 874 tcp_getcred(SYSCTL_HANDLER_ARGS) 875 { 876 struct sockaddr_in addrs[2]; 877 struct inpcb *inp; 878 int error, s; 879 880 error = suser(req->p); 881 if (error) 882 return (error); 883 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 884 if (error) 885 return (error); 886 s = splnet(); 887 inp = in_pcblookup_hash(&tcbinfo, addrs[1].sin_addr, addrs[1].sin_port, 888 addrs[0].sin_addr, addrs[0].sin_port, 0, NULL); 889 if (inp == NULL || inp->inp_socket == NULL) { 890 error = ENOENT; 891 goto out; 892 } 893 error = SYSCTL_OUT(req, inp->inp_socket->so_cred, sizeof(struct ucred)); 894 out: 895 splx(s); 896 return (error); 897 } 898 899 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, getcred, CTLTYPE_OPAQUE|CTLFLAG_RW, 900 0, 0, tcp_getcred, "S,ucred", "Get the ucred of a TCP connection"); 901 902 #ifdef INET6 903 static int 904 tcp6_getcred(SYSCTL_HANDLER_ARGS) 905 { 906 struct sockaddr_in6 addrs[2]; 907 struct inpcb *inp; 908 int error, s, mapped = 0; 909 910 error = suser(req->p); 911 if (error) 912 return (error); 913 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 914 if (error) 915 return (error); 916 if (IN6_IS_ADDR_V4MAPPED(&addrs[0].sin6_addr)) { 917 if (IN6_IS_ADDR_V4MAPPED(&addrs[1].sin6_addr)) 918 mapped = 1; 919 else 920 return (EINVAL); 921 } 922 s = splnet(); 923 if (mapped == 1) 924 inp = in_pcblookup_hash(&tcbinfo, 925 *(struct in_addr *)&addrs[1].sin6_addr.s6_addr[12], 926 addrs[1].sin6_port, 927 *(struct in_addr *)&addrs[0].sin6_addr.s6_addr[12], 928 addrs[0].sin6_port, 929 0, NULL); 930 else 931 inp = in6_pcblookup_hash(&tcbinfo, &addrs[1].sin6_addr, 932 addrs[1].sin6_port, 933 &addrs[0].sin6_addr, addrs[0].sin6_port, 934 0, NULL); 935 if (inp == NULL || inp->inp_socket == NULL) { 936 error = ENOENT; 937 goto out; 938 } 939 error = SYSCTL_OUT(req, inp->inp_socket->so_cred, 940 sizeof(struct ucred)); 941 out: 942 splx(s); 943 return (error); 944 } 945 946 SYSCTL_PROC(_net_inet6_tcp6, OID_AUTO, getcred, CTLTYPE_OPAQUE|CTLFLAG_RW, 947 0, 0, 948 tcp6_getcred, "S,ucred", "Get the ucred of a TCP6 connection"); 949 #endif 950 951 952 void 953 tcp_ctlinput(cmd, sa, vip) 954 int cmd; 955 struct sockaddr *sa; 956 void *vip; 957 { 958 register struct ip *ip = vip; 959 register struct tcphdr *th; 960 void (*notify) __P((struct inpcb *, int)) = tcp_notify; 961 962 if (cmd == PRC_QUENCH) 963 notify = tcp_quench; 964 else if (cmd == PRC_MSGSIZE) 965 notify = tcp_mtudisc; 966 else if (!PRC_IS_REDIRECT(cmd) && 967 ((unsigned)cmd > PRC_NCMDS || inetctlerrmap[cmd] == 0)) 968 return; 969 if (ip) { 970 th = (struct tcphdr *)((caddr_t)ip 971 + (IP_VHL_HL(ip->ip_vhl) << 2)); 972 in_pcbnotify(&tcb, sa, th->th_dport, ip->ip_src, th->th_sport, 973 cmd, notify); 974 } else 975 in_pcbnotify(&tcb, sa, 0, zeroin_addr, 0, cmd, notify); 976 } 977 978 #ifdef INET6 979 void 980 tcp6_ctlinput(cmd, sa, d) 981 int cmd; 982 struct sockaddr *sa; 983 void *d; 984 { 985 register struct tcphdr *thp; 986 struct tcphdr th; 987 void (*notify) __P((struct inpcb *, int)) = tcp_notify; 988 struct sockaddr_in6 sa6; 989 struct ip6_hdr *ip6; 990 struct mbuf *m; 991 int off; 992 993 if (sa->sa_family != AF_INET6 || 994 sa->sa_len != sizeof(struct sockaddr_in6)) 995 return; 996 997 if (cmd == PRC_QUENCH) 998 notify = tcp_quench; 999 else if (cmd == PRC_MSGSIZE) 1000 notify = tcp_mtudisc; 1001 else if (!PRC_IS_REDIRECT(cmd) && 1002 ((unsigned)cmd > PRC_NCMDS || inet6ctlerrmap[cmd] == 0)) 1003 return; 1004 1005 /* if the parameter is from icmp6, decode it. */ 1006 if (d != NULL) { 1007 struct ip6ctlparam *ip6cp = (struct ip6ctlparam *)d; 1008 m = ip6cp->ip6c_m; 1009 ip6 = ip6cp->ip6c_ip6; 1010 off = ip6cp->ip6c_off; 1011 } else { 1012 m = NULL; 1013 ip6 = NULL; 1014 off = 0; /* fool gcc */ 1015 } 1016 1017 /* 1018 * Translate addresses into internal form. 1019 * Sa check if it is AF_INET6 is done at the top of this funciton. 1020 */ 1021 sa6 = *(struct sockaddr_in6 *)sa; 1022 if (IN6_IS_ADDR_LINKLOCAL(&sa6.sin6_addr) != 0 && m != NULL && 1023 m->m_pkthdr.rcvif != NULL) 1024 sa6.sin6_addr.s6_addr16[1] = htons(m->m_pkthdr.rcvif->if_index); 1025 1026 if (ip6) { 1027 /* 1028 * XXX: We assume that when IPV6 is non NULL, 1029 * M and OFF are valid. 1030 */ 1031 struct in6_addr s; 1032 1033 /* translate addresses into internal form */ 1034 memcpy(&s, &ip6->ip6_src, sizeof(s)); 1035 if (IN6_IS_ADDR_LINKLOCAL(&s) != 0 && m != NULL && 1036 m->m_pkthdr.rcvif != NULL) 1037 s.s6_addr16[1] = htons(m->m_pkthdr.rcvif->if_index); 1038 1039 /* check if we can safely examine src and dst ports */ 1040 if (m->m_pkthdr.len < off + sizeof(th)) 1041 return; 1042 1043 if (m->m_len < off + sizeof(th)) { 1044 /* 1045 * this should be rare case 1046 * because now MINCLSIZE is "(MHLEN + 1)", 1047 * so we compromise on this copy... 1048 */ 1049 m_copydata(m, off, sizeof(th), (caddr_t)&th); 1050 thp = &th; 1051 } else 1052 thp = (struct tcphdr *)(mtod(m, caddr_t) + off); 1053 in6_pcbnotify(&tcb, (struct sockaddr *)&sa6, thp->th_dport, 1054 &s, thp->th_sport, cmd, notify); 1055 } else 1056 in6_pcbnotify(&tcb, (struct sockaddr *)&sa6, 0, &zeroin6_addr, 1057 0, cmd, notify); 1058 } 1059 #endif /* INET6 */ 1060 1061 /* 1062 * When a source quench is received, close congestion window 1063 * to one segment. We will gradually open it again as we proceed. 1064 */ 1065 void 1066 tcp_quench(inp, errno) 1067 struct inpcb *inp; 1068 int errno; 1069 { 1070 struct tcpcb *tp = intotcpcb(inp); 1071 1072 if (tp) 1073 tp->snd_cwnd = tp->t_maxseg; 1074 } 1075 1076 /* 1077 * When `need fragmentation' ICMP is received, update our idea of the MSS 1078 * based on the new value in the route. Also nudge TCP to send something, 1079 * since we know the packet we just sent was dropped. 1080 * This duplicates some code in the tcp_mss() function in tcp_input.c. 1081 */ 1082 void 1083 tcp_mtudisc(inp, errno) 1084 struct inpcb *inp; 1085 int errno; 1086 { 1087 struct tcpcb *tp = intotcpcb(inp); 1088 struct rtentry *rt; 1089 struct rmxp_tao *taop; 1090 struct socket *so = inp->inp_socket; 1091 int offered; 1092 int mss; 1093 #ifdef INET6 1094 int isipv6 = (tp->t_inpcb->inp_vflag & INP_IPV6) != 0; 1095 #endif /* INET6 */ 1096 1097 if (tp) { 1098 #ifdef INET6 1099 if (isipv6) 1100 rt = tcp_rtlookup6(inp); 1101 else 1102 #endif /* INET6 */ 1103 rt = tcp_rtlookup(inp); 1104 if (!rt || !rt->rt_rmx.rmx_mtu) { 1105 tp->t_maxopd = tp->t_maxseg = 1106 #ifdef INET6 1107 isipv6 ? tcp_v6mssdflt : 1108 #endif /* INET6 */ 1109 tcp_mssdflt; 1110 return; 1111 } 1112 taop = rmx_taop(rt->rt_rmx); 1113 offered = taop->tao_mssopt; 1114 mss = rt->rt_rmx.rmx_mtu - 1115 #ifdef INET6 1116 (isipv6 ? 1117 sizeof(struct ip6_hdr) + sizeof(struct tcphdr) : 1118 #endif /* INET6 */ 1119 sizeof(struct tcpiphdr) 1120 #ifdef INET6 1121 ) 1122 #endif /* INET6 */ 1123 ; 1124 1125 if (offered) 1126 mss = min(mss, offered); 1127 /* 1128 * XXX - The above conditional probably violates the TCP 1129 * spec. The problem is that, since we don't know the 1130 * other end's MSS, we are supposed to use a conservative 1131 * default. But, if we do that, then MTU discovery will 1132 * never actually take place, because the conservative 1133 * default is much less than the MTUs typically seen 1134 * on the Internet today. For the moment, we'll sweep 1135 * this under the carpet. 1136 * 1137 * The conservative default might not actually be a problem 1138 * if the only case this occurs is when sending an initial 1139 * SYN with options and data to a host we've never talked 1140 * to before. Then, they will reply with an MSS value which 1141 * will get recorded and the new parameters should get 1142 * recomputed. For Further Study. 1143 */ 1144 if (tp->t_maxopd <= mss) 1145 return; 1146 tp->t_maxopd = mss; 1147 1148 if ((tp->t_flags & (TF_REQ_TSTMP|TF_NOOPT)) == TF_REQ_TSTMP && 1149 (tp->t_flags & TF_RCVD_TSTMP) == TF_RCVD_TSTMP) 1150 mss -= TCPOLEN_TSTAMP_APPA; 1151 if ((tp->t_flags & (TF_REQ_CC|TF_NOOPT)) == TF_REQ_CC && 1152 (tp->t_flags & TF_RCVD_CC) == TF_RCVD_CC) 1153 mss -= TCPOLEN_CC_APPA; 1154 #if (MCLBYTES & (MCLBYTES - 1)) == 0 1155 if (mss > MCLBYTES) 1156 mss &= ~(MCLBYTES-1); 1157 #else 1158 if (mss > MCLBYTES) 1159 mss = mss / MCLBYTES * MCLBYTES; 1160 #endif 1161 if (so->so_snd.sb_hiwat < mss) 1162 mss = so->so_snd.sb_hiwat; 1163 1164 tp->t_maxseg = mss; 1165 1166 tcpstat.tcps_mturesent++; 1167 tp->t_rtttime = 0; 1168 tp->snd_nxt = tp->snd_una; 1169 tcp_output(tp); 1170 } 1171 } 1172 1173 /* 1174 * Look-up the routing entry to the peer of this inpcb. If no route 1175 * is found and it cannot be allocated the return NULL. This routine 1176 * is called by TCP routines that access the rmx structure and by tcp_mss 1177 * to get the interface MTU. 1178 */ 1179 struct rtentry * 1180 tcp_rtlookup(inp) 1181 struct inpcb *inp; 1182 { 1183 struct route *ro; 1184 struct rtentry *rt; 1185 1186 ro = &inp->inp_route; 1187 rt = ro->ro_rt; 1188 if (rt == NULL || !(rt->rt_flags & RTF_UP)) { 1189 /* No route yet, so try to acquire one */ 1190 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1191 ro->ro_dst.sa_family = AF_INET; 1192 ro->ro_dst.sa_len = sizeof(ro->ro_dst); 1193 ((struct sockaddr_in *) &ro->ro_dst)->sin_addr = 1194 inp->inp_faddr; 1195 rtalloc(ro); 1196 rt = ro->ro_rt; 1197 } 1198 } 1199 return rt; 1200 } 1201 1202 #ifdef INET6 1203 struct rtentry * 1204 tcp_rtlookup6(inp) 1205 struct inpcb *inp; 1206 { 1207 struct route_in6 *ro6; 1208 struct rtentry *rt; 1209 1210 ro6 = &inp->in6p_route; 1211 rt = ro6->ro_rt; 1212 if (rt == NULL || !(rt->rt_flags & RTF_UP)) { 1213 /* No route yet, so try to acquire one */ 1214 if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) { 1215 ro6->ro_dst.sin6_family = AF_INET6; 1216 ro6->ro_dst.sin6_len = sizeof(ro6->ro_dst); 1217 ro6->ro_dst.sin6_addr = inp->in6p_faddr; 1218 rtalloc((struct route *)ro6); 1219 rt = ro6->ro_rt; 1220 } 1221 } 1222 return rt; 1223 } 1224 #endif /* INET6 */ 1225 1226 #ifdef IPSEC 1227 /* compute ESP/AH header size for TCP, including outer IP header. */ 1228 size_t 1229 ipsec_hdrsiz_tcp(tp) 1230 struct tcpcb *tp; 1231 { 1232 struct inpcb *inp; 1233 struct mbuf *m; 1234 size_t hdrsiz; 1235 struct ip *ip; 1236 #ifdef INET6 1237 struct ip6_hdr *ip6; 1238 #endif /* INET6 */ 1239 struct tcphdr *th; 1240 1241 if (!tp || !tp->t_template || !(inp = tp->t_inpcb)) 1242 return 0; 1243 MGETHDR(m, M_DONTWAIT, MT_DATA); 1244 if (!m) 1245 return 0; 1246 1247 #ifdef INET6 1248 if ((inp->inp_vflag & INP_IPV6) != 0) { 1249 ip6 = mtod(m, struct ip6_hdr *); 1250 th = (struct tcphdr *)(ip6 + 1); 1251 m->m_pkthdr.len = m->m_len = 1252 sizeof(struct ip6_hdr) + sizeof(struct tcphdr); 1253 bcopy((caddr_t)tp->t_template->tt_ipgen, (caddr_t)ip6, 1254 sizeof(struct ip6_hdr)); 1255 bcopy((caddr_t)&tp->t_template->tt_t, (caddr_t)th, 1256 sizeof(struct tcphdr)); 1257 hdrsiz = ipsec6_hdrsiz(m, IPSEC_DIR_OUTBOUND, inp); 1258 } else 1259 #endif /* INET6 */ 1260 { 1261 ip = mtod(m, struct ip *); 1262 th = (struct tcphdr *)(ip + 1); 1263 m->m_pkthdr.len = m->m_len = sizeof(struct tcpiphdr); 1264 bcopy((caddr_t)tp->t_template->tt_ipgen, (caddr_t)ip, 1265 sizeof(struct ip)); 1266 bcopy((caddr_t)&tp->t_template->tt_t, (caddr_t)th, 1267 sizeof(struct tcphdr)); 1268 hdrsiz = ipsec4_hdrsiz(m, IPSEC_DIR_OUTBOUND, inp); 1269 } 1270 1271 m_free(m); 1272 return hdrsiz; 1273 } 1274 #endif /*IPSEC*/ 1275 1276 /* 1277 * Return a pointer to the cached information about the remote host. 1278 * The cached information is stored in the protocol specific part of 1279 * the route metrics. 1280 */ 1281 struct rmxp_tao * 1282 tcp_gettaocache(inp) 1283 struct inpcb *inp; 1284 { 1285 struct rtentry *rt; 1286 1287 #ifdef INET6 1288 if ((inp->inp_vflag & INP_IPV6) != 0) 1289 rt = tcp_rtlookup6(inp); 1290 else 1291 #endif /* INET6 */ 1292 rt = tcp_rtlookup(inp); 1293 1294 /* Make sure this is a host route and is up. */ 1295 if (rt == NULL || 1296 (rt->rt_flags & (RTF_UP|RTF_HOST)) != (RTF_UP|RTF_HOST)) 1297 return NULL; 1298 1299 return rmx_taop(rt->rt_rmx); 1300 } 1301 1302 /* 1303 * Clear all the TAO cache entries, called from tcp_init. 1304 * 1305 * XXX 1306 * This routine is just an empty one, because we assume that the routing 1307 * routing tables are initialized at the same time when TCP, so there is 1308 * nothing in the cache left over. 1309 */ 1310 static void 1311 tcp_cleartaocache() 1312 { 1313 } 1314