1 /* $NetBSD: tcp_subr.c,v 1.246 2011/12/31 20:41:59 christos Exp $ */ 2 3 /* 4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the project nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 /*- 33 * Copyright (c) 1997, 1998, 2000, 2001, 2008 The NetBSD Foundation, Inc. 34 * All rights reserved. 35 * 36 * This code is derived from software contributed to The NetBSD Foundation 37 * by Jason R. Thorpe and Kevin M. Lahey of the Numerical Aerospace Simulation 38 * Facility, NASA Ames Research Center. 39 * 40 * Redistribution and use in source and binary forms, with or without 41 * modification, are permitted provided that the following conditions 42 * are met: 43 * 1. Redistributions of source code must retain the above copyright 44 * notice, this list of conditions and the following disclaimer. 45 * 2. Redistributions in binary form must reproduce the above copyright 46 * notice, this list of conditions and the following disclaimer in the 47 * documentation and/or other materials provided with the distribution. 48 * 49 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 50 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 51 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 52 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 53 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 54 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 55 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 56 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 57 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 58 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 59 * POSSIBILITY OF SUCH DAMAGE. 60 */ 61 62 /* 63 * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995 64 * The Regents of the University of California. All rights reserved. 65 * 66 * Redistribution and use in source and binary forms, with or without 67 * modification, are permitted provided that the following conditions 68 * are met: 69 * 1. Redistributions of source code must retain the above copyright 70 * notice, this list of conditions and the following disclaimer. 71 * 2. Redistributions in binary form must reproduce the above copyright 72 * notice, this list of conditions and the following disclaimer in the 73 * documentation and/or other materials provided with the distribution. 74 * 3. Neither the name of the University nor the names of its contributors 75 * may be used to endorse or promote products derived from this software 76 * without specific prior written permission. 77 * 78 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 79 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 80 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 81 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 82 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 83 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 84 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 85 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 86 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 87 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 88 * SUCH DAMAGE. 89 * 90 * @(#)tcp_subr.c 8.2 (Berkeley) 5/24/95 91 */ 92 93 #include <sys/cdefs.h> 94 __KERNEL_RCSID(0, "$NetBSD: tcp_subr.c,v 1.246 2011/12/31 20:41:59 christos Exp $"); 95 96 #include "opt_inet.h" 97 #include "opt_ipsec.h" 98 #include "opt_tcp_compat_42.h" 99 #include "opt_inet_csum.h" 100 #include "opt_mbuftrace.h" 101 102 #include <sys/param.h> 103 #include <sys/proc.h> 104 #include <sys/systm.h> 105 #include <sys/malloc.h> 106 #include <sys/mbuf.h> 107 #include <sys/socket.h> 108 #include <sys/socketvar.h> 109 #include <sys/protosw.h> 110 #include <sys/errno.h> 111 #include <sys/kernel.h> 112 #include <sys/pool.h> 113 #include <sys/md5.h> 114 #include <sys/cprng.h> 115 116 #include <net/route.h> 117 #include <net/if.h> 118 119 #include <netinet/in.h> 120 #include <netinet/in_systm.h> 121 #include <netinet/ip.h> 122 #include <netinet/in_pcb.h> 123 #include <netinet/ip_var.h> 124 #include <netinet/ip_icmp.h> 125 126 #ifdef INET6 127 #ifndef INET 128 #include <netinet/in.h> 129 #endif 130 #include <netinet/ip6.h> 131 #include <netinet6/in6_pcb.h> 132 #include <netinet6/ip6_var.h> 133 #include <netinet6/in6_var.h> 134 #include <netinet6/ip6protosw.h> 135 #include <netinet/icmp6.h> 136 #include <netinet6/nd6.h> 137 #endif 138 139 #include <netinet/tcp.h> 140 #include <netinet/tcp_fsm.h> 141 #include <netinet/tcp_seq.h> 142 #include <netinet/tcp_timer.h> 143 #include <netinet/tcp_var.h> 144 #include <netinet/tcp_vtw.h> 145 #include <netinet/tcp_private.h> 146 #include <netinet/tcp_congctl.h> 147 #include <netinet/tcpip.h> 148 149 #ifdef KAME_IPSEC 150 #include <netinet6/ipsec.h> 151 #include <netkey/key.h> 152 #endif /*KAME_IPSEC*/ 153 154 #ifdef FAST_IPSEC 155 #include <netipsec/ipsec.h> 156 #include <netipsec/xform.h> 157 #ifdef INET6 158 #include <netipsec/ipsec6.h> 159 #endif 160 #include <netipsec/key.h> 161 #endif /* FAST_IPSEC*/ 162 163 164 struct inpcbtable tcbtable; /* head of queue of active tcpcb's */ 165 u_int32_t tcp_now; /* slow ticks, for RFC 1323 timestamps */ 166 167 percpu_t *tcpstat_percpu; 168 169 /* patchable/settable parameters for tcp */ 170 int tcp_mssdflt = TCP_MSS; 171 int tcp_minmss = TCP_MINMSS; 172 int tcp_rttdflt = TCPTV_SRTTDFLT / PR_SLOWHZ; 173 int tcp_do_rfc1323 = 1; /* window scaling / timestamps (obsolete) */ 174 int tcp_do_rfc1948 = 0; /* ISS by cryptographic hash */ 175 int tcp_do_sack = 1; /* selective acknowledgement */ 176 int tcp_do_win_scale = 1; /* RFC1323 window scaling */ 177 int tcp_do_timestamps = 1; /* RFC1323 timestamps */ 178 int tcp_ack_on_push = 0; /* set to enable immediate ACK-on-PUSH */ 179 int tcp_do_ecn = 0; /* Explicit Congestion Notification */ 180 #ifndef TCP_INIT_WIN 181 #define TCP_INIT_WIN 0 /* initial slow start window */ 182 #endif 183 #ifndef TCP_INIT_WIN_LOCAL 184 #define TCP_INIT_WIN_LOCAL 4 /* initial slow start window for local nets */ 185 #endif 186 int tcp_init_win = TCP_INIT_WIN; 187 int tcp_init_win_local = TCP_INIT_WIN_LOCAL; 188 int tcp_mss_ifmtu = 0; 189 #ifdef TCP_COMPAT_42 190 int tcp_compat_42 = 1; 191 #else 192 int tcp_compat_42 = 0; 193 #endif 194 int tcp_rst_ppslim = 100; /* 100pps */ 195 int tcp_ackdrop_ppslim = 100; /* 100pps */ 196 int tcp_do_loopback_cksum = 0; 197 int tcp_do_abc = 1; /* RFC3465 Appropriate byte counting. */ 198 int tcp_abc_aggressive = 1; /* 1: L=2*SMSS 0: L=1*SMSS */ 199 int tcp_sack_tp_maxholes = 32; 200 int tcp_sack_globalmaxholes = 1024; 201 int tcp_sack_globalholes = 0; 202 int tcp_ecn_maxretries = 1; 203 int tcp_msl_enable = 1; /* enable TIME_WAIT truncation */ 204 int tcp_msl_loop = PR_SLOWHZ; /* MSL for loopback */ 205 int tcp_msl_local = 5 * PR_SLOWHZ; /* MSL for 'local' */ 206 int tcp_msl_remote = TCPTV_MSL; /* MSL otherwise */ 207 int tcp_msl_remote_threshold = TCPTV_SRTTDFLT; /* RTT threshold */ 208 int tcp_rttlocal = 0; /* Use RTT to decide who's 'local' */ 209 210 int tcp4_vtw_enable = 0; /* 1 to enable */ 211 int tcp6_vtw_enable = 0; /* 1 to enable */ 212 int tcp_vtw_was_enabled = 0; 213 int tcp_vtw_entries = 1 << 16; /* 64K vestigial TIME_WAIT entries */ 214 215 /* tcb hash */ 216 #ifndef TCBHASHSIZE 217 #define TCBHASHSIZE 128 218 #endif 219 int tcbhashsize = TCBHASHSIZE; 220 221 /* syn hash parameters */ 222 #define TCP_SYN_HASH_SIZE 293 223 #define TCP_SYN_BUCKET_SIZE 35 224 int tcp_syn_cache_size = TCP_SYN_HASH_SIZE; 225 int tcp_syn_cache_limit = TCP_SYN_HASH_SIZE*TCP_SYN_BUCKET_SIZE; 226 int tcp_syn_bucket_limit = 3*TCP_SYN_BUCKET_SIZE; 227 struct syn_cache_head tcp_syn_cache[TCP_SYN_HASH_SIZE]; 228 229 int tcp_freeq(struct tcpcb *); 230 231 #ifdef INET 232 void tcp_mtudisc_callback(struct in_addr); 233 #endif 234 #ifdef INET6 235 void tcp6_mtudisc_callback(struct in6_addr *); 236 #endif 237 238 #ifdef INET6 239 void tcp6_mtudisc(struct in6pcb *, int); 240 #endif 241 242 static struct pool tcpcb_pool; 243 244 static int tcp_drainwanted; 245 246 #ifdef TCP_CSUM_COUNTERS 247 #include <sys/device.h> 248 249 #if defined(INET) 250 struct evcnt tcp_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 251 NULL, "tcp", "hwcsum bad"); 252 struct evcnt tcp_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 253 NULL, "tcp", "hwcsum ok"); 254 struct evcnt tcp_hwcsum_data = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 255 NULL, "tcp", "hwcsum data"); 256 struct evcnt tcp_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 257 NULL, "tcp", "swcsum"); 258 259 EVCNT_ATTACH_STATIC(tcp_hwcsum_bad); 260 EVCNT_ATTACH_STATIC(tcp_hwcsum_ok); 261 EVCNT_ATTACH_STATIC(tcp_hwcsum_data); 262 EVCNT_ATTACH_STATIC(tcp_swcsum); 263 #endif /* defined(INET) */ 264 265 #if defined(INET6) 266 struct evcnt tcp6_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 267 NULL, "tcp6", "hwcsum bad"); 268 struct evcnt tcp6_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 269 NULL, "tcp6", "hwcsum ok"); 270 struct evcnt tcp6_hwcsum_data = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 271 NULL, "tcp6", "hwcsum data"); 272 struct evcnt tcp6_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 273 NULL, "tcp6", "swcsum"); 274 275 EVCNT_ATTACH_STATIC(tcp6_hwcsum_bad); 276 EVCNT_ATTACH_STATIC(tcp6_hwcsum_ok); 277 EVCNT_ATTACH_STATIC(tcp6_hwcsum_data); 278 EVCNT_ATTACH_STATIC(tcp6_swcsum); 279 #endif /* defined(INET6) */ 280 #endif /* TCP_CSUM_COUNTERS */ 281 282 283 #ifdef TCP_OUTPUT_COUNTERS 284 #include <sys/device.h> 285 286 struct evcnt tcp_output_bigheader = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 287 NULL, "tcp", "output big header"); 288 struct evcnt tcp_output_predict_hit = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 289 NULL, "tcp", "output predict hit"); 290 struct evcnt tcp_output_predict_miss = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 291 NULL, "tcp", "output predict miss"); 292 struct evcnt tcp_output_copysmall = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 293 NULL, "tcp", "output copy small"); 294 struct evcnt tcp_output_copybig = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 295 NULL, "tcp", "output copy big"); 296 struct evcnt tcp_output_refbig = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 297 NULL, "tcp", "output reference big"); 298 299 EVCNT_ATTACH_STATIC(tcp_output_bigheader); 300 EVCNT_ATTACH_STATIC(tcp_output_predict_hit); 301 EVCNT_ATTACH_STATIC(tcp_output_predict_miss); 302 EVCNT_ATTACH_STATIC(tcp_output_copysmall); 303 EVCNT_ATTACH_STATIC(tcp_output_copybig); 304 EVCNT_ATTACH_STATIC(tcp_output_refbig); 305 306 #endif /* TCP_OUTPUT_COUNTERS */ 307 308 #ifdef TCP_REASS_COUNTERS 309 #include <sys/device.h> 310 311 struct evcnt tcp_reass_ = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 312 NULL, "tcp_reass", "calls"); 313 struct evcnt tcp_reass_empty = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 314 &tcp_reass_, "tcp_reass", "insert into empty queue"); 315 struct evcnt tcp_reass_iteration[8] = { 316 EVCNT_INITIALIZER(EVCNT_TYPE_MISC, &tcp_reass_, "tcp_reass", ">7 iterations"), 317 EVCNT_INITIALIZER(EVCNT_TYPE_MISC, &tcp_reass_, "tcp_reass", "1 iteration"), 318 EVCNT_INITIALIZER(EVCNT_TYPE_MISC, &tcp_reass_, "tcp_reass", "2 iterations"), 319 EVCNT_INITIALIZER(EVCNT_TYPE_MISC, &tcp_reass_, "tcp_reass", "3 iterations"), 320 EVCNT_INITIALIZER(EVCNT_TYPE_MISC, &tcp_reass_, "tcp_reass", "4 iterations"), 321 EVCNT_INITIALIZER(EVCNT_TYPE_MISC, &tcp_reass_, "tcp_reass", "5 iterations"), 322 EVCNT_INITIALIZER(EVCNT_TYPE_MISC, &tcp_reass_, "tcp_reass", "6 iterations"), 323 EVCNT_INITIALIZER(EVCNT_TYPE_MISC, &tcp_reass_, "tcp_reass", "7 iterations"), 324 }; 325 struct evcnt tcp_reass_prependfirst = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 326 &tcp_reass_, "tcp_reass", "prepend to first"); 327 struct evcnt tcp_reass_prepend = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 328 &tcp_reass_, "tcp_reass", "prepend"); 329 struct evcnt tcp_reass_insert = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 330 &tcp_reass_, "tcp_reass", "insert"); 331 struct evcnt tcp_reass_inserttail = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 332 &tcp_reass_, "tcp_reass", "insert at tail"); 333 struct evcnt tcp_reass_append = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 334 &tcp_reass_, "tcp_reass", "append"); 335 struct evcnt tcp_reass_appendtail = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 336 &tcp_reass_, "tcp_reass", "append to tail fragment"); 337 struct evcnt tcp_reass_overlaptail = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 338 &tcp_reass_, "tcp_reass", "overlap at end"); 339 struct evcnt tcp_reass_overlapfront = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 340 &tcp_reass_, "tcp_reass", "overlap at start"); 341 struct evcnt tcp_reass_segdup = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 342 &tcp_reass_, "tcp_reass", "duplicate segment"); 343 struct evcnt tcp_reass_fragdup = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 344 &tcp_reass_, "tcp_reass", "duplicate fragment"); 345 346 EVCNT_ATTACH_STATIC(tcp_reass_); 347 EVCNT_ATTACH_STATIC(tcp_reass_empty); 348 EVCNT_ATTACH_STATIC2(tcp_reass_iteration, 0); 349 EVCNT_ATTACH_STATIC2(tcp_reass_iteration, 1); 350 EVCNT_ATTACH_STATIC2(tcp_reass_iteration, 2); 351 EVCNT_ATTACH_STATIC2(tcp_reass_iteration, 3); 352 EVCNT_ATTACH_STATIC2(tcp_reass_iteration, 4); 353 EVCNT_ATTACH_STATIC2(tcp_reass_iteration, 5); 354 EVCNT_ATTACH_STATIC2(tcp_reass_iteration, 6); 355 EVCNT_ATTACH_STATIC2(tcp_reass_iteration, 7); 356 EVCNT_ATTACH_STATIC(tcp_reass_prependfirst); 357 EVCNT_ATTACH_STATIC(tcp_reass_prepend); 358 EVCNT_ATTACH_STATIC(tcp_reass_insert); 359 EVCNT_ATTACH_STATIC(tcp_reass_inserttail); 360 EVCNT_ATTACH_STATIC(tcp_reass_append); 361 EVCNT_ATTACH_STATIC(tcp_reass_appendtail); 362 EVCNT_ATTACH_STATIC(tcp_reass_overlaptail); 363 EVCNT_ATTACH_STATIC(tcp_reass_overlapfront); 364 EVCNT_ATTACH_STATIC(tcp_reass_segdup); 365 EVCNT_ATTACH_STATIC(tcp_reass_fragdup); 366 367 #endif /* TCP_REASS_COUNTERS */ 368 369 #ifdef MBUFTRACE 370 struct mowner tcp_mowner = MOWNER_INIT("tcp", ""); 371 struct mowner tcp_rx_mowner = MOWNER_INIT("tcp", "rx"); 372 struct mowner tcp_tx_mowner = MOWNER_INIT("tcp", "tx"); 373 struct mowner tcp_sock_mowner = MOWNER_INIT("tcp", "sock"); 374 struct mowner tcp_sock_rx_mowner = MOWNER_INIT("tcp", "sock rx"); 375 struct mowner tcp_sock_tx_mowner = MOWNER_INIT("tcp", "sock tx"); 376 #endif 377 378 /* 379 * Tcp initialization 380 */ 381 void 382 tcp_init(void) 383 { 384 int hlen; 385 386 in_pcbinit(&tcbtable, tcbhashsize, tcbhashsize); 387 pool_init(&tcpcb_pool, sizeof(struct tcpcb), 0, 0, 0, "tcpcbpl", 388 NULL, IPL_SOFTNET); 389 390 hlen = sizeof(struct ip) + sizeof(struct tcphdr); 391 #ifdef INET6 392 if (sizeof(struct ip) < sizeof(struct ip6_hdr)) 393 hlen = sizeof(struct ip6_hdr) + sizeof(struct tcphdr); 394 #endif 395 if (max_protohdr < hlen) 396 max_protohdr = hlen; 397 if (max_linkhdr + hlen > MHLEN) 398 panic("tcp_init"); 399 400 #ifdef INET 401 icmp_mtudisc_callback_register(tcp_mtudisc_callback); 402 #endif 403 #ifdef INET6 404 icmp6_mtudisc_callback_register(tcp6_mtudisc_callback); 405 #endif 406 407 tcp_usrreq_init(); 408 409 /* Initialize timer state. */ 410 tcp_timer_init(); 411 412 /* Initialize the compressed state engine. */ 413 syn_cache_init(); 414 415 /* Initialize the congestion control algorithms. */ 416 tcp_congctl_init(); 417 418 /* Initialize the TCPCB template. */ 419 tcp_tcpcb_template(); 420 421 /* Initialize reassembly queue */ 422 tcpipqent_init(); 423 424 /* SACK */ 425 tcp_sack_init(); 426 427 MOWNER_ATTACH(&tcp_tx_mowner); 428 MOWNER_ATTACH(&tcp_rx_mowner); 429 MOWNER_ATTACH(&tcp_reass_mowner); 430 MOWNER_ATTACH(&tcp_sock_mowner); 431 MOWNER_ATTACH(&tcp_sock_tx_mowner); 432 MOWNER_ATTACH(&tcp_sock_rx_mowner); 433 MOWNER_ATTACH(&tcp_mowner); 434 435 tcpstat_percpu = percpu_alloc(sizeof(uint64_t) * TCP_NSTATS); 436 437 vtw_earlyinit(); 438 } 439 440 /* 441 * Create template to be used to send tcp packets on a connection. 442 * Call after host entry created, allocates an mbuf and fills 443 * in a skeletal tcp/ip header, minimizing the amount of work 444 * necessary when the connection is used. 445 */ 446 struct mbuf * 447 tcp_template(struct tcpcb *tp) 448 { 449 struct inpcb *inp = tp->t_inpcb; 450 #ifdef INET6 451 struct in6pcb *in6p = tp->t_in6pcb; 452 #endif 453 struct tcphdr *n; 454 struct mbuf *m; 455 int hlen; 456 457 switch (tp->t_family) { 458 case AF_INET: 459 hlen = sizeof(struct ip); 460 if (inp) 461 break; 462 #ifdef INET6 463 if (in6p) { 464 /* mapped addr case */ 465 if (IN6_IS_ADDR_V4MAPPED(&in6p->in6p_laddr) 466 && IN6_IS_ADDR_V4MAPPED(&in6p->in6p_faddr)) 467 break; 468 } 469 #endif 470 return NULL; /*EINVAL*/ 471 #ifdef INET6 472 case AF_INET6: 473 hlen = sizeof(struct ip6_hdr); 474 if (in6p) { 475 /* more sainty check? */ 476 break; 477 } 478 return NULL; /*EINVAL*/ 479 #endif 480 default: 481 hlen = 0; /*pacify gcc*/ 482 return NULL; /*EAFNOSUPPORT*/ 483 } 484 #ifdef DIAGNOSTIC 485 if (hlen + sizeof(struct tcphdr) > MCLBYTES) 486 panic("mclbytes too small for t_template"); 487 #endif 488 m = tp->t_template; 489 if (m && m->m_len == hlen + sizeof(struct tcphdr)) 490 ; 491 else { 492 if (m) 493 m_freem(m); 494 m = tp->t_template = NULL; 495 MGETHDR(m, M_DONTWAIT, MT_HEADER); 496 if (m && hlen + sizeof(struct tcphdr) > MHLEN) { 497 MCLGET(m, M_DONTWAIT); 498 if ((m->m_flags & M_EXT) == 0) { 499 m_free(m); 500 m = NULL; 501 } 502 } 503 if (m == NULL) 504 return NULL; 505 MCLAIM(m, &tcp_mowner); 506 m->m_pkthdr.len = m->m_len = hlen + sizeof(struct tcphdr); 507 } 508 509 memset(mtod(m, void *), 0, m->m_len); 510 511 n = (struct tcphdr *)(mtod(m, char *) + hlen); 512 513 switch (tp->t_family) { 514 case AF_INET: 515 { 516 struct ipovly *ipov; 517 mtod(m, struct ip *)->ip_v = 4; 518 mtod(m, struct ip *)->ip_hl = hlen >> 2; 519 ipov = mtod(m, struct ipovly *); 520 ipov->ih_pr = IPPROTO_TCP; 521 ipov->ih_len = htons(sizeof(struct tcphdr)); 522 if (inp) { 523 ipov->ih_src = inp->inp_laddr; 524 ipov->ih_dst = inp->inp_faddr; 525 } 526 #ifdef INET6 527 else if (in6p) { 528 /* mapped addr case */ 529 bcopy(&in6p->in6p_laddr.s6_addr32[3], &ipov->ih_src, 530 sizeof(ipov->ih_src)); 531 bcopy(&in6p->in6p_faddr.s6_addr32[3], &ipov->ih_dst, 532 sizeof(ipov->ih_dst)); 533 } 534 #endif 535 /* 536 * Compute the pseudo-header portion of the checksum 537 * now. We incrementally add in the TCP option and 538 * payload lengths later, and then compute the TCP 539 * checksum right before the packet is sent off onto 540 * the wire. 541 */ 542 n->th_sum = in_cksum_phdr(ipov->ih_src.s_addr, 543 ipov->ih_dst.s_addr, 544 htons(sizeof(struct tcphdr) + IPPROTO_TCP)); 545 break; 546 } 547 #ifdef INET6 548 case AF_INET6: 549 { 550 struct ip6_hdr *ip6; 551 mtod(m, struct ip *)->ip_v = 6; 552 ip6 = mtod(m, struct ip6_hdr *); 553 ip6->ip6_nxt = IPPROTO_TCP; 554 ip6->ip6_plen = htons(sizeof(struct tcphdr)); 555 ip6->ip6_src = in6p->in6p_laddr; 556 ip6->ip6_dst = in6p->in6p_faddr; 557 ip6->ip6_flow = in6p->in6p_flowinfo & IPV6_FLOWINFO_MASK; 558 if (ip6_auto_flowlabel) { 559 ip6->ip6_flow &= ~IPV6_FLOWLABEL_MASK; 560 ip6->ip6_flow |= 561 (htonl(ip6_randomflowlabel()) & IPV6_FLOWLABEL_MASK); 562 } 563 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 564 ip6->ip6_vfc |= IPV6_VERSION; 565 566 /* 567 * Compute the pseudo-header portion of the checksum 568 * now. We incrementally add in the TCP option and 569 * payload lengths later, and then compute the TCP 570 * checksum right before the packet is sent off onto 571 * the wire. 572 */ 573 n->th_sum = in6_cksum_phdr(&in6p->in6p_laddr, 574 &in6p->in6p_faddr, htonl(sizeof(struct tcphdr)), 575 htonl(IPPROTO_TCP)); 576 break; 577 } 578 #endif 579 } 580 if (inp) { 581 n->th_sport = inp->inp_lport; 582 n->th_dport = inp->inp_fport; 583 } 584 #ifdef INET6 585 else if (in6p) { 586 n->th_sport = in6p->in6p_lport; 587 n->th_dport = in6p->in6p_fport; 588 } 589 #endif 590 n->th_seq = 0; 591 n->th_ack = 0; 592 n->th_x2 = 0; 593 n->th_off = 5; 594 n->th_flags = 0; 595 n->th_win = 0; 596 n->th_urp = 0; 597 return (m); 598 } 599 600 /* 601 * Send a single message to the TCP at address specified by 602 * the given TCP/IP header. If m == 0, then we make a copy 603 * of the tcpiphdr at ti and send directly to the addressed host. 604 * This is used to force keep alive messages out using the TCP 605 * template for a connection tp->t_template. If flags are given 606 * then we send a message back to the TCP which originated the 607 * segment ti, and discard the mbuf containing it and any other 608 * attached mbufs. 609 * 610 * In any case the ack and sequence number of the transmitted 611 * segment are as specified by the parameters. 612 */ 613 int 614 tcp_respond(struct tcpcb *tp, struct mbuf *template, struct mbuf *m, 615 struct tcphdr *th0, tcp_seq ack, tcp_seq seq, int flags) 616 { 617 #ifdef INET6 618 struct rtentry *rt; 619 #endif 620 struct route *ro; 621 int error, tlen, win = 0; 622 int hlen; 623 struct ip *ip; 624 #ifdef INET6 625 struct ip6_hdr *ip6; 626 #endif 627 int family; /* family on packet, not inpcb/in6pcb! */ 628 struct tcphdr *th; 629 struct socket *so; 630 631 if (tp != NULL && (flags & TH_RST) == 0) { 632 #ifdef DIAGNOSTIC 633 if (tp->t_inpcb && tp->t_in6pcb) 634 panic("tcp_respond: both t_inpcb and t_in6pcb are set"); 635 #endif 636 #ifdef INET 637 if (tp->t_inpcb) 638 win = sbspace(&tp->t_inpcb->inp_socket->so_rcv); 639 #endif 640 #ifdef INET6 641 if (tp->t_in6pcb) 642 win = sbspace(&tp->t_in6pcb->in6p_socket->so_rcv); 643 #endif 644 } 645 646 th = NULL; /* Quell uninitialized warning */ 647 ip = NULL; 648 #ifdef INET6 649 ip6 = NULL; 650 #endif 651 if (m == 0) { 652 if (!template) 653 return EINVAL; 654 655 /* get family information from template */ 656 switch (mtod(template, struct ip *)->ip_v) { 657 case 4: 658 family = AF_INET; 659 hlen = sizeof(struct ip); 660 break; 661 #ifdef INET6 662 case 6: 663 family = AF_INET6; 664 hlen = sizeof(struct ip6_hdr); 665 break; 666 #endif 667 default: 668 return EAFNOSUPPORT; 669 } 670 671 MGETHDR(m, M_DONTWAIT, MT_HEADER); 672 if (m) { 673 MCLAIM(m, &tcp_tx_mowner); 674 MCLGET(m, M_DONTWAIT); 675 if ((m->m_flags & M_EXT) == 0) { 676 m_free(m); 677 m = NULL; 678 } 679 } 680 if (m == NULL) 681 return (ENOBUFS); 682 683 if (tcp_compat_42) 684 tlen = 1; 685 else 686 tlen = 0; 687 688 m->m_data += max_linkhdr; 689 bcopy(mtod(template, void *), mtod(m, void *), 690 template->m_len); 691 switch (family) { 692 case AF_INET: 693 ip = mtod(m, struct ip *); 694 th = (struct tcphdr *)(ip + 1); 695 break; 696 #ifdef INET6 697 case AF_INET6: 698 ip6 = mtod(m, struct ip6_hdr *); 699 th = (struct tcphdr *)(ip6 + 1); 700 break; 701 #endif 702 #if 0 703 default: 704 /* noone will visit here */ 705 m_freem(m); 706 return EAFNOSUPPORT; 707 #endif 708 } 709 flags = TH_ACK; 710 } else { 711 712 if ((m->m_flags & M_PKTHDR) == 0) { 713 #if 0 714 printf("non PKTHDR to tcp_respond\n"); 715 #endif 716 m_freem(m); 717 return EINVAL; 718 } 719 #ifdef DIAGNOSTIC 720 if (!th0) 721 panic("th0 == NULL in tcp_respond"); 722 #endif 723 724 /* get family information from m */ 725 switch (mtod(m, struct ip *)->ip_v) { 726 case 4: 727 family = AF_INET; 728 hlen = sizeof(struct ip); 729 ip = mtod(m, struct ip *); 730 break; 731 #ifdef INET6 732 case 6: 733 family = AF_INET6; 734 hlen = sizeof(struct ip6_hdr); 735 ip6 = mtod(m, struct ip6_hdr *); 736 break; 737 #endif 738 default: 739 m_freem(m); 740 return EAFNOSUPPORT; 741 } 742 /* clear h/w csum flags inherited from rx packet */ 743 m->m_pkthdr.csum_flags = 0; 744 745 if ((flags & TH_SYN) == 0 || sizeof(*th0) > (th0->th_off << 2)) 746 tlen = sizeof(*th0); 747 else 748 tlen = th0->th_off << 2; 749 750 if (m->m_len > hlen + tlen && (m->m_flags & M_EXT) == 0 && 751 mtod(m, char *) + hlen == (char *)th0) { 752 m->m_len = hlen + tlen; 753 m_freem(m->m_next); 754 m->m_next = NULL; 755 } else { 756 struct mbuf *n; 757 758 #ifdef DIAGNOSTIC 759 if (max_linkhdr + hlen + tlen > MCLBYTES) { 760 m_freem(m); 761 return EMSGSIZE; 762 } 763 #endif 764 MGETHDR(n, M_DONTWAIT, MT_HEADER); 765 if (n && max_linkhdr + hlen + tlen > MHLEN) { 766 MCLGET(n, M_DONTWAIT); 767 if ((n->m_flags & M_EXT) == 0) { 768 m_freem(n); 769 n = NULL; 770 } 771 } 772 if (!n) { 773 m_freem(m); 774 return ENOBUFS; 775 } 776 777 MCLAIM(n, &tcp_tx_mowner); 778 n->m_data += max_linkhdr; 779 n->m_len = hlen + tlen; 780 m_copyback(n, 0, hlen, mtod(m, void *)); 781 m_copyback(n, hlen, tlen, (void *)th0); 782 783 m_freem(m); 784 m = n; 785 n = NULL; 786 } 787 788 #define xchg(a,b,type) { type t; t=a; a=b; b=t; } 789 switch (family) { 790 case AF_INET: 791 ip = mtod(m, struct ip *); 792 th = (struct tcphdr *)(ip + 1); 793 ip->ip_p = IPPROTO_TCP; 794 xchg(ip->ip_dst, ip->ip_src, struct in_addr); 795 ip->ip_p = IPPROTO_TCP; 796 break; 797 #ifdef INET6 798 case AF_INET6: 799 ip6 = mtod(m, struct ip6_hdr *); 800 th = (struct tcphdr *)(ip6 + 1); 801 ip6->ip6_nxt = IPPROTO_TCP; 802 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); 803 ip6->ip6_nxt = IPPROTO_TCP; 804 break; 805 #endif 806 #if 0 807 default: 808 /* noone will visit here */ 809 m_freem(m); 810 return EAFNOSUPPORT; 811 #endif 812 } 813 xchg(th->th_dport, th->th_sport, u_int16_t); 814 #undef xchg 815 tlen = 0; /*be friendly with the following code*/ 816 } 817 th->th_seq = htonl(seq); 818 th->th_ack = htonl(ack); 819 th->th_x2 = 0; 820 if ((flags & TH_SYN) == 0) { 821 if (tp) 822 win >>= tp->rcv_scale; 823 if (win > TCP_MAXWIN) 824 win = TCP_MAXWIN; 825 th->th_win = htons((u_int16_t)win); 826 th->th_off = sizeof (struct tcphdr) >> 2; 827 tlen += sizeof(*th); 828 } else 829 tlen += th->th_off << 2; 830 m->m_len = hlen + tlen; 831 m->m_pkthdr.len = hlen + tlen; 832 m->m_pkthdr.rcvif = NULL; 833 th->th_flags = flags; 834 th->th_urp = 0; 835 836 switch (family) { 837 #ifdef INET 838 case AF_INET: 839 { 840 struct ipovly *ipov = (struct ipovly *)ip; 841 memset(ipov->ih_x1, 0, sizeof ipov->ih_x1); 842 ipov->ih_len = htons((u_int16_t)tlen); 843 844 th->th_sum = 0; 845 th->th_sum = in_cksum(m, hlen + tlen); 846 ip->ip_len = htons(hlen + tlen); 847 ip->ip_ttl = ip_defttl; 848 break; 849 } 850 #endif 851 #ifdef INET6 852 case AF_INET6: 853 { 854 th->th_sum = 0; 855 th->th_sum = in6_cksum(m, IPPROTO_TCP, sizeof(struct ip6_hdr), 856 tlen); 857 ip6->ip6_plen = htons(tlen); 858 if (tp && tp->t_in6pcb) { 859 struct ifnet *oifp; 860 ro = &tp->t_in6pcb->in6p_route; 861 oifp = (rt = rtcache_validate(ro)) != NULL ? rt->rt_ifp 862 : NULL; 863 ip6->ip6_hlim = in6_selecthlim(tp->t_in6pcb, oifp); 864 } else 865 ip6->ip6_hlim = ip6_defhlim; 866 ip6->ip6_flow &= ~IPV6_FLOWINFO_MASK; 867 if (ip6_auto_flowlabel) { 868 ip6->ip6_flow |= 869 (htonl(ip6_randomflowlabel()) & IPV6_FLOWLABEL_MASK); 870 } 871 break; 872 } 873 #endif 874 } 875 876 if (tp && tp->t_inpcb) 877 so = tp->t_inpcb->inp_socket; 878 #ifdef INET6 879 else if (tp && tp->t_in6pcb) 880 so = tp->t_in6pcb->in6p_socket; 881 #endif 882 else 883 so = NULL; 884 885 if (tp != NULL && tp->t_inpcb != NULL) { 886 ro = &tp->t_inpcb->inp_route; 887 #ifdef DIAGNOSTIC 888 if (family != AF_INET) 889 panic("tcp_respond: address family mismatch"); 890 if (!in_hosteq(ip->ip_dst, tp->t_inpcb->inp_faddr)) { 891 panic("tcp_respond: ip_dst %x != inp_faddr %x", 892 ntohl(ip->ip_dst.s_addr), 893 ntohl(tp->t_inpcb->inp_faddr.s_addr)); 894 } 895 #endif 896 } 897 #ifdef INET6 898 else if (tp != NULL && tp->t_in6pcb != NULL) { 899 ro = (struct route *)&tp->t_in6pcb->in6p_route; 900 #ifdef DIAGNOSTIC 901 if (family == AF_INET) { 902 if (!IN6_IS_ADDR_V4MAPPED(&tp->t_in6pcb->in6p_faddr)) 903 panic("tcp_respond: not mapped addr"); 904 if (memcmp(&ip->ip_dst, 905 &tp->t_in6pcb->in6p_faddr.s6_addr32[3], 906 sizeof(ip->ip_dst)) != 0) { 907 panic("tcp_respond: ip_dst != in6p_faddr"); 908 } 909 } else if (family == AF_INET6) { 910 if (!IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, 911 &tp->t_in6pcb->in6p_faddr)) 912 panic("tcp_respond: ip6_dst != in6p_faddr"); 913 } else 914 panic("tcp_respond: address family mismatch"); 915 #endif 916 } 917 #endif 918 else 919 ro = NULL; 920 921 switch (family) { 922 #ifdef INET 923 case AF_INET: 924 error = ip_output(m, NULL, ro, 925 (tp && tp->t_mtudisc ? IP_MTUDISC : 0), NULL, so); 926 break; 927 #endif 928 #ifdef INET6 929 case AF_INET6: 930 error = ip6_output(m, NULL, ro, 0, NULL, so, NULL); 931 break; 932 #endif 933 default: 934 error = EAFNOSUPPORT; 935 break; 936 } 937 938 return (error); 939 } 940 941 /* 942 * Template TCPCB. Rather than zeroing a new TCPCB and initializing 943 * a bunch of members individually, we maintain this template for the 944 * static and mostly-static components of the TCPCB, and copy it into 945 * the new TCPCB instead. 946 */ 947 static struct tcpcb tcpcb_template = { 948 .t_srtt = TCPTV_SRTTBASE, 949 .t_rttmin = TCPTV_MIN, 950 951 .snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT, 952 .snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT, 953 .snd_numholes = 0, 954 955 .t_partialacks = -1, 956 .t_bytes_acked = 0, 957 }; 958 959 /* 960 * Updates the TCPCB template whenever a parameter that would affect 961 * the template is changed. 962 */ 963 void 964 tcp_tcpcb_template(void) 965 { 966 struct tcpcb *tp = &tcpcb_template; 967 int flags; 968 969 tp->t_peermss = tcp_mssdflt; 970 tp->t_ourmss = tcp_mssdflt; 971 tp->t_segsz = tcp_mssdflt; 972 973 flags = 0; 974 if (tcp_do_rfc1323 && tcp_do_win_scale) 975 flags |= TF_REQ_SCALE; 976 if (tcp_do_rfc1323 && tcp_do_timestamps) 977 flags |= TF_REQ_TSTMP; 978 tp->t_flags = flags; 979 980 /* 981 * Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no 982 * rtt estimate. Set rttvar so that srtt + 2 * rttvar gives 983 * reasonable initial retransmit time. 984 */ 985 tp->t_rttvar = tcp_rttdflt * PR_SLOWHZ << (TCP_RTTVAR_SHIFT + 2 - 1); 986 TCPT_RANGESET(tp->t_rxtcur, TCP_REXMTVAL(tp), 987 TCPTV_MIN, TCPTV_REXMTMAX); 988 989 /* Keep Alive */ 990 tp->t_keepinit = tcp_keepinit; 991 tp->t_keepidle = tcp_keepidle; 992 tp->t_keepintvl = tcp_keepintvl; 993 tp->t_keepcnt = tcp_keepcnt; 994 tp->t_maxidle = tp->t_keepcnt * tp->t_keepintvl; 995 996 /* MSL */ 997 tp->t_msl = TCPTV_MSL; 998 } 999 1000 /* 1001 * Create a new TCP control block, making an 1002 * empty reassembly queue and hooking it to the argument 1003 * protocol control block. 1004 */ 1005 /* family selects inpcb, or in6pcb */ 1006 struct tcpcb * 1007 tcp_newtcpcb(int family, void *aux) 1008 { 1009 #ifdef INET6 1010 struct rtentry *rt; 1011 #endif 1012 struct tcpcb *tp; 1013 int i; 1014 1015 /* XXX Consider using a pool_cache for speed. */ 1016 tp = pool_get(&tcpcb_pool, PR_NOWAIT); /* splsoftnet via tcp_usrreq */ 1017 if (tp == NULL) 1018 return (NULL); 1019 memcpy(tp, &tcpcb_template, sizeof(*tp)); 1020 TAILQ_INIT(&tp->segq); 1021 TAILQ_INIT(&tp->timeq); 1022 tp->t_family = family; /* may be overridden later on */ 1023 TAILQ_INIT(&tp->snd_holes); 1024 LIST_INIT(&tp->t_sc); /* XXX can template this */ 1025 1026 /* Don't sweat this loop; hopefully the compiler will unroll it. */ 1027 for (i = 0; i < TCPT_NTIMERS; i++) { 1028 callout_init(&tp->t_timer[i], CALLOUT_MPSAFE); 1029 TCP_TIMER_INIT(tp, i); 1030 } 1031 callout_init(&tp->t_delack_ch, CALLOUT_MPSAFE); 1032 1033 switch (family) { 1034 case AF_INET: 1035 { 1036 struct inpcb *inp = (struct inpcb *)aux; 1037 1038 inp->inp_ip.ip_ttl = ip_defttl; 1039 inp->inp_ppcb = (void *)tp; 1040 1041 tp->t_inpcb = inp; 1042 tp->t_mtudisc = ip_mtudisc; 1043 break; 1044 } 1045 #ifdef INET6 1046 case AF_INET6: 1047 { 1048 struct in6pcb *in6p = (struct in6pcb *)aux; 1049 1050 in6p->in6p_ip6.ip6_hlim = in6_selecthlim(in6p, 1051 (rt = rtcache_validate(&in6p->in6p_route)) != NULL 1052 ? rt->rt_ifp 1053 : NULL); 1054 in6p->in6p_ppcb = (void *)tp; 1055 1056 tp->t_in6pcb = in6p; 1057 /* for IPv6, always try to run path MTU discovery */ 1058 tp->t_mtudisc = 1; 1059 break; 1060 } 1061 #endif /* INET6 */ 1062 default: 1063 for (i = 0; i < TCPT_NTIMERS; i++) 1064 callout_destroy(&tp->t_timer[i]); 1065 callout_destroy(&tp->t_delack_ch); 1066 pool_put(&tcpcb_pool, tp); /* splsoftnet via tcp_usrreq */ 1067 return (NULL); 1068 } 1069 1070 /* 1071 * Initialize our timebase. When we send timestamps, we take 1072 * the delta from tcp_now -- this means each connection always 1073 * gets a timebase of 1, which makes it, among other things, 1074 * more difficult to determine how long a system has been up, 1075 * and thus how many TCP sequence increments have occurred. 1076 * 1077 * We start with 1, because 0 doesn't work with linux, which 1078 * considers timestamp 0 in a SYN packet as a bug and disables 1079 * timestamps. 1080 */ 1081 tp->ts_timebase = tcp_now - 1; 1082 1083 tcp_congctl_select(tp, tcp_congctl_global_name); 1084 1085 return (tp); 1086 } 1087 1088 /* 1089 * Drop a TCP connection, reporting 1090 * the specified error. If connection is synchronized, 1091 * then send a RST to peer. 1092 */ 1093 struct tcpcb * 1094 tcp_drop(struct tcpcb *tp, int errno) 1095 { 1096 struct socket *so = NULL; 1097 1098 #ifdef DIAGNOSTIC 1099 if (tp->t_inpcb && tp->t_in6pcb) 1100 panic("tcp_drop: both t_inpcb and t_in6pcb are set"); 1101 #endif 1102 #ifdef INET 1103 if (tp->t_inpcb) 1104 so = tp->t_inpcb->inp_socket; 1105 #endif 1106 #ifdef INET6 1107 if (tp->t_in6pcb) 1108 so = tp->t_in6pcb->in6p_socket; 1109 #endif 1110 if (!so) 1111 return NULL; 1112 1113 if (TCPS_HAVERCVDSYN(tp->t_state)) { 1114 tp->t_state = TCPS_CLOSED; 1115 (void) tcp_output(tp); 1116 TCP_STATINC(TCP_STAT_DROPS); 1117 } else 1118 TCP_STATINC(TCP_STAT_CONNDROPS); 1119 if (errno == ETIMEDOUT && tp->t_softerror) 1120 errno = tp->t_softerror; 1121 so->so_error = errno; 1122 return (tcp_close(tp)); 1123 } 1124 1125 /* 1126 * Close a TCP control block: 1127 * discard all space held by the tcp 1128 * discard internet protocol block 1129 * wake up any sleepers 1130 */ 1131 struct tcpcb * 1132 tcp_close(struct tcpcb *tp) 1133 { 1134 struct inpcb *inp; 1135 #ifdef INET6 1136 struct in6pcb *in6p; 1137 #endif 1138 struct socket *so; 1139 #ifdef RTV_RTT 1140 struct rtentry *rt; 1141 #endif 1142 struct route *ro; 1143 int j; 1144 1145 inp = tp->t_inpcb; 1146 #ifdef INET6 1147 in6p = tp->t_in6pcb; 1148 #endif 1149 so = NULL; 1150 ro = NULL; 1151 if (inp) { 1152 so = inp->inp_socket; 1153 ro = &inp->inp_route; 1154 } 1155 #ifdef INET6 1156 else if (in6p) { 1157 so = in6p->in6p_socket; 1158 ro = (struct route *)&in6p->in6p_route; 1159 } 1160 #endif 1161 1162 #ifdef RTV_RTT 1163 /* 1164 * If we sent enough data to get some meaningful characteristics, 1165 * save them in the routing entry. 'Enough' is arbitrarily 1166 * defined as the sendpipesize (default 4K) * 16. This would 1167 * give us 16 rtt samples assuming we only get one sample per 1168 * window (the usual case on a long haul net). 16 samples is 1169 * enough for the srtt filter to converge to within 5% of the correct 1170 * value; fewer samples and we could save a very bogus rtt. 1171 * 1172 * Don't update the default route's characteristics and don't 1173 * update anything that the user "locked". 1174 */ 1175 if (SEQ_LT(tp->iss + so->so_snd.sb_hiwat * 16, tp->snd_max) && 1176 ro && (rt = rtcache_validate(ro)) != NULL && 1177 !in_nullhost(satocsin(rt_getkey(rt))->sin_addr)) { 1178 u_long i = 0; 1179 1180 if ((rt->rt_rmx.rmx_locks & RTV_RTT) == 0) { 1181 i = tp->t_srtt * 1182 ((RTM_RTTUNIT / PR_SLOWHZ) >> (TCP_RTT_SHIFT + 2)); 1183 if (rt->rt_rmx.rmx_rtt && i) 1184 /* 1185 * filter this update to half the old & half 1186 * the new values, converting scale. 1187 * See route.h and tcp_var.h for a 1188 * description of the scaling constants. 1189 */ 1190 rt->rt_rmx.rmx_rtt = 1191 (rt->rt_rmx.rmx_rtt + i) / 2; 1192 else 1193 rt->rt_rmx.rmx_rtt = i; 1194 } 1195 if ((rt->rt_rmx.rmx_locks & RTV_RTTVAR) == 0) { 1196 i = tp->t_rttvar * 1197 ((RTM_RTTUNIT / PR_SLOWHZ) >> (TCP_RTTVAR_SHIFT + 2)); 1198 if (rt->rt_rmx.rmx_rttvar && i) 1199 rt->rt_rmx.rmx_rttvar = 1200 (rt->rt_rmx.rmx_rttvar + i) / 2; 1201 else 1202 rt->rt_rmx.rmx_rttvar = i; 1203 } 1204 /* 1205 * update the pipelimit (ssthresh) if it has been updated 1206 * already or if a pipesize was specified & the threshhold 1207 * got below half the pipesize. I.e., wait for bad news 1208 * before we start updating, then update on both good 1209 * and bad news. 1210 */ 1211 if (((rt->rt_rmx.rmx_locks & RTV_SSTHRESH) == 0 && 1212 (i = tp->snd_ssthresh) && rt->rt_rmx.rmx_ssthresh) || 1213 i < (rt->rt_rmx.rmx_sendpipe / 2)) { 1214 /* 1215 * convert the limit from user data bytes to 1216 * packets then to packet data bytes. 1217 */ 1218 i = (i + tp->t_segsz / 2) / tp->t_segsz; 1219 if (i < 2) 1220 i = 2; 1221 i *= (u_long)(tp->t_segsz + sizeof (struct tcpiphdr)); 1222 if (rt->rt_rmx.rmx_ssthresh) 1223 rt->rt_rmx.rmx_ssthresh = 1224 (rt->rt_rmx.rmx_ssthresh + i) / 2; 1225 else 1226 rt->rt_rmx.rmx_ssthresh = i; 1227 } 1228 } 1229 #endif /* RTV_RTT */ 1230 /* free the reassembly queue, if any */ 1231 TCP_REASS_LOCK(tp); 1232 (void) tcp_freeq(tp); 1233 TCP_REASS_UNLOCK(tp); 1234 1235 /* free the SACK holes list. */ 1236 tcp_free_sackholes(tp); 1237 tcp_congctl_release(tp); 1238 syn_cache_cleanup(tp); 1239 1240 if (tp->t_template) { 1241 m_free(tp->t_template); 1242 tp->t_template = NULL; 1243 } 1244 1245 /* 1246 * Detaching the pcb will unlock the socket/tcpcb, and stopping 1247 * the timers can also drop the lock. We need to prevent access 1248 * to the tcpcb as it's half torn down. Flag the pcb as dead 1249 * (prevents access by timers) and only then detach it. 1250 */ 1251 tp->t_flags |= TF_DEAD; 1252 if (inp) { 1253 inp->inp_ppcb = 0; 1254 soisdisconnected(so); 1255 in_pcbdetach(inp); 1256 } 1257 #ifdef INET6 1258 else if (in6p) { 1259 in6p->in6p_ppcb = 0; 1260 soisdisconnected(so); 1261 in6_pcbdetach(in6p); 1262 } 1263 #endif 1264 /* 1265 * pcb is no longer visble elsewhere, so we can safely release 1266 * the lock in callout_halt() if needed. 1267 */ 1268 TCP_STATINC(TCP_STAT_CLOSED); 1269 for (j = 0; j < TCPT_NTIMERS; j++) { 1270 callout_halt(&tp->t_timer[j], softnet_lock); 1271 callout_destroy(&tp->t_timer[j]); 1272 } 1273 callout_halt(&tp->t_delack_ch, softnet_lock); 1274 callout_destroy(&tp->t_delack_ch); 1275 pool_put(&tcpcb_pool, tp); 1276 1277 return NULL; 1278 } 1279 1280 int 1281 tcp_freeq(struct tcpcb *tp) 1282 { 1283 struct ipqent *qe; 1284 int rv = 0; 1285 #ifdef TCPREASS_DEBUG 1286 int i = 0; 1287 #endif 1288 1289 TCP_REASS_LOCK_CHECK(tp); 1290 1291 while ((qe = TAILQ_FIRST(&tp->segq)) != NULL) { 1292 #ifdef TCPREASS_DEBUG 1293 printf("tcp_freeq[%p,%d]: %u:%u(%u) 0x%02x\n", 1294 tp, i++, qe->ipqe_seq, qe->ipqe_seq + qe->ipqe_len, 1295 qe->ipqe_len, qe->ipqe_flags & (TH_SYN|TH_FIN|TH_RST)); 1296 #endif 1297 TAILQ_REMOVE(&tp->segq, qe, ipqe_q); 1298 TAILQ_REMOVE(&tp->timeq, qe, ipqe_timeq); 1299 m_freem(qe->ipqe_m); 1300 tcpipqent_free(qe); 1301 rv = 1; 1302 } 1303 tp->t_segqlen = 0; 1304 KASSERT(TAILQ_EMPTY(&tp->timeq)); 1305 return (rv); 1306 } 1307 1308 void 1309 tcp_fasttimo(void) 1310 { 1311 if (tcp_drainwanted) { 1312 tcp_drain(); 1313 tcp_drainwanted = 0; 1314 } 1315 } 1316 1317 void 1318 tcp_drainstub(void) 1319 { 1320 tcp_drainwanted = 1; 1321 } 1322 1323 /* 1324 * Protocol drain routine. Called when memory is in short supply. 1325 * Called from pr_fasttimo thus a callout context. 1326 */ 1327 void 1328 tcp_drain(void) 1329 { 1330 struct inpcb_hdr *inph; 1331 struct tcpcb *tp; 1332 1333 mutex_enter(softnet_lock); 1334 KERNEL_LOCK(1, NULL); 1335 1336 /* 1337 * Free the sequence queue of all TCP connections. 1338 */ 1339 CIRCLEQ_FOREACH(inph, &tcbtable.inpt_queue, inph_queue) { 1340 switch (inph->inph_af) { 1341 case AF_INET: 1342 tp = intotcpcb((struct inpcb *)inph); 1343 break; 1344 #ifdef INET6 1345 case AF_INET6: 1346 tp = in6totcpcb((struct in6pcb *)inph); 1347 break; 1348 #endif 1349 default: 1350 tp = NULL; 1351 break; 1352 } 1353 if (tp != NULL) { 1354 /* 1355 * We may be called from a device's interrupt 1356 * context. If the tcpcb is already busy, 1357 * just bail out now. 1358 */ 1359 if (tcp_reass_lock_try(tp) == 0) 1360 continue; 1361 if (tcp_freeq(tp)) 1362 TCP_STATINC(TCP_STAT_CONNSDRAINED); 1363 TCP_REASS_UNLOCK(tp); 1364 } 1365 } 1366 1367 KERNEL_UNLOCK_ONE(NULL); 1368 mutex_exit(softnet_lock); 1369 } 1370 1371 /* 1372 * Notify a tcp user of an asynchronous error; 1373 * store error as soft error, but wake up user 1374 * (for now, won't do anything until can select for soft error). 1375 */ 1376 void 1377 tcp_notify(struct inpcb *inp, int error) 1378 { 1379 struct tcpcb *tp = (struct tcpcb *)inp->inp_ppcb; 1380 struct socket *so = inp->inp_socket; 1381 1382 /* 1383 * Ignore some errors if we are hooked up. 1384 * If connection hasn't completed, has retransmitted several times, 1385 * and receives a second error, give up now. This is better 1386 * than waiting a long time to establish a connection that 1387 * can never complete. 1388 */ 1389 if (tp->t_state == TCPS_ESTABLISHED && 1390 (error == EHOSTUNREACH || error == ENETUNREACH || 1391 error == EHOSTDOWN)) { 1392 return; 1393 } else if (TCPS_HAVEESTABLISHED(tp->t_state) == 0 && 1394 tp->t_rxtshift > 3 && tp->t_softerror) 1395 so->so_error = error; 1396 else 1397 tp->t_softerror = error; 1398 cv_broadcast(&so->so_cv); 1399 sorwakeup(so); 1400 sowwakeup(so); 1401 } 1402 1403 #ifdef INET6 1404 void 1405 tcp6_notify(struct in6pcb *in6p, int error) 1406 { 1407 struct tcpcb *tp = (struct tcpcb *)in6p->in6p_ppcb; 1408 struct socket *so = in6p->in6p_socket; 1409 1410 /* 1411 * Ignore some errors if we are hooked up. 1412 * If connection hasn't completed, has retransmitted several times, 1413 * and receives a second error, give up now. This is better 1414 * than waiting a long time to establish a connection that 1415 * can never complete. 1416 */ 1417 if (tp->t_state == TCPS_ESTABLISHED && 1418 (error == EHOSTUNREACH || error == ENETUNREACH || 1419 error == EHOSTDOWN)) { 1420 return; 1421 } else if (TCPS_HAVEESTABLISHED(tp->t_state) == 0 && 1422 tp->t_rxtshift > 3 && tp->t_softerror) 1423 so->so_error = error; 1424 else 1425 tp->t_softerror = error; 1426 cv_broadcast(&so->so_cv); 1427 sorwakeup(so); 1428 sowwakeup(so); 1429 } 1430 #endif 1431 1432 #ifdef INET6 1433 void * 1434 tcp6_ctlinput(int cmd, const struct sockaddr *sa, void *d) 1435 { 1436 struct tcphdr th; 1437 void (*notify)(struct in6pcb *, int) = tcp6_notify; 1438 int nmatch; 1439 struct ip6_hdr *ip6; 1440 const struct sockaddr_in6 *sa6_src = NULL; 1441 const struct sockaddr_in6 *sa6 = (const struct sockaddr_in6 *)sa; 1442 struct mbuf *m; 1443 int off; 1444 1445 if (sa->sa_family != AF_INET6 || 1446 sa->sa_len != sizeof(struct sockaddr_in6)) 1447 return NULL; 1448 if ((unsigned)cmd >= PRC_NCMDS) 1449 return NULL; 1450 else if (cmd == PRC_QUENCH) { 1451 /* 1452 * Don't honor ICMP Source Quench messages meant for 1453 * TCP connections. 1454 */ 1455 return NULL; 1456 } else if (PRC_IS_REDIRECT(cmd)) 1457 notify = in6_rtchange, d = NULL; 1458 else if (cmd == PRC_MSGSIZE) 1459 ; /* special code is present, see below */ 1460 else if (cmd == PRC_HOSTDEAD) 1461 d = NULL; 1462 else if (inet6ctlerrmap[cmd] == 0) 1463 return NULL; 1464 1465 /* if the parameter is from icmp6, decode it. */ 1466 if (d != NULL) { 1467 struct ip6ctlparam *ip6cp = (struct ip6ctlparam *)d; 1468 m = ip6cp->ip6c_m; 1469 ip6 = ip6cp->ip6c_ip6; 1470 off = ip6cp->ip6c_off; 1471 sa6_src = ip6cp->ip6c_src; 1472 } else { 1473 m = NULL; 1474 ip6 = NULL; 1475 sa6_src = &sa6_any; 1476 off = 0; 1477 } 1478 1479 if (ip6) { 1480 /* 1481 * XXX: We assume that when ip6 is non NULL, 1482 * M and OFF are valid. 1483 */ 1484 1485 /* check if we can safely examine src and dst ports */ 1486 if (m->m_pkthdr.len < off + sizeof(th)) { 1487 if (cmd == PRC_MSGSIZE) 1488 icmp6_mtudisc_update((struct ip6ctlparam *)d, 0); 1489 return NULL; 1490 } 1491 1492 memset(&th, 0, sizeof(th)); 1493 m_copydata(m, off, sizeof(th), (void *)&th); 1494 1495 if (cmd == PRC_MSGSIZE) { 1496 int valid = 0; 1497 1498 /* 1499 * Check to see if we have a valid TCP connection 1500 * corresponding to the address in the ICMPv6 message 1501 * payload. 1502 */ 1503 if (in6_pcblookup_connect(&tcbtable, &sa6->sin6_addr, 1504 th.th_dport, 1505 (const struct in6_addr *)&sa6_src->sin6_addr, 1506 th.th_sport, 0, 0)) 1507 valid++; 1508 1509 /* 1510 * Depending on the value of "valid" and routing table 1511 * size (mtudisc_{hi,lo}wat), we will: 1512 * - recalcurate the new MTU and create the 1513 * corresponding routing entry, or 1514 * - ignore the MTU change notification. 1515 */ 1516 icmp6_mtudisc_update((struct ip6ctlparam *)d, valid); 1517 1518 /* 1519 * no need to call in6_pcbnotify, it should have been 1520 * called via callback if necessary 1521 */ 1522 return NULL; 1523 } 1524 1525 nmatch = in6_pcbnotify(&tcbtable, sa, th.th_dport, 1526 (const struct sockaddr *)sa6_src, th.th_sport, cmd, NULL, notify); 1527 if (nmatch == 0 && syn_cache_count && 1528 (inet6ctlerrmap[cmd] == EHOSTUNREACH || 1529 inet6ctlerrmap[cmd] == ENETUNREACH || 1530 inet6ctlerrmap[cmd] == EHOSTDOWN)) 1531 syn_cache_unreach((const struct sockaddr *)sa6_src, 1532 sa, &th); 1533 } else { 1534 (void) in6_pcbnotify(&tcbtable, sa, 0, 1535 (const struct sockaddr *)sa6_src, 0, cmd, NULL, notify); 1536 } 1537 1538 return NULL; 1539 } 1540 #endif 1541 1542 #ifdef INET 1543 /* assumes that ip header and tcp header are contiguous on mbuf */ 1544 void * 1545 tcp_ctlinput(int cmd, const struct sockaddr *sa, void *v) 1546 { 1547 struct ip *ip = v; 1548 struct tcphdr *th; 1549 struct icmp *icp; 1550 extern const int inetctlerrmap[]; 1551 void (*notify)(struct inpcb *, int) = tcp_notify; 1552 int errno; 1553 int nmatch; 1554 struct tcpcb *tp; 1555 u_int mtu; 1556 tcp_seq seq; 1557 struct inpcb *inp; 1558 #ifdef INET6 1559 struct in6pcb *in6p; 1560 struct in6_addr src6, dst6; 1561 #endif 1562 1563 if (sa->sa_family != AF_INET || 1564 sa->sa_len != sizeof(struct sockaddr_in)) 1565 return NULL; 1566 if ((unsigned)cmd >= PRC_NCMDS) 1567 return NULL; 1568 errno = inetctlerrmap[cmd]; 1569 if (cmd == PRC_QUENCH) 1570 /* 1571 * Don't honor ICMP Source Quench messages meant for 1572 * TCP connections. 1573 */ 1574 return NULL; 1575 else if (PRC_IS_REDIRECT(cmd)) 1576 notify = in_rtchange, ip = 0; 1577 else if (cmd == PRC_MSGSIZE && ip && ip->ip_v == 4) { 1578 /* 1579 * Check to see if we have a valid TCP connection 1580 * corresponding to the address in the ICMP message 1581 * payload. 1582 * 1583 * Boundary check is made in icmp_input(), with ICMP_ADVLENMIN. 1584 */ 1585 th = (struct tcphdr *)((char *)ip + (ip->ip_hl << 2)); 1586 #ifdef INET6 1587 memset(&src6, 0, sizeof(src6)); 1588 memset(&dst6, 0, sizeof(dst6)); 1589 src6.s6_addr16[5] = dst6.s6_addr16[5] = 0xffff; 1590 memcpy(&src6.s6_addr32[3], &ip->ip_src, sizeof(struct in_addr)); 1591 memcpy(&dst6.s6_addr32[3], &ip->ip_dst, sizeof(struct in_addr)); 1592 #endif 1593 if ((inp = in_pcblookup_connect(&tcbtable, ip->ip_dst, 1594 th->th_dport, ip->ip_src, th->th_sport, 0)) != NULL) 1595 #ifdef INET6 1596 in6p = NULL; 1597 #else 1598 ; 1599 #endif 1600 #ifdef INET6 1601 else if ((in6p = in6_pcblookup_connect(&tcbtable, &dst6, 1602 th->th_dport, &src6, th->th_sport, 0, 0)) != NULL) 1603 ; 1604 #endif 1605 else 1606 return NULL; 1607 1608 /* 1609 * Now that we've validated that we are actually communicating 1610 * with the host indicated in the ICMP message, locate the 1611 * ICMP header, recalculate the new MTU, and create the 1612 * corresponding routing entry. 1613 */ 1614 icp = (struct icmp *)((char *)ip - 1615 offsetof(struct icmp, icmp_ip)); 1616 if (inp) { 1617 if ((tp = intotcpcb(inp)) == NULL) 1618 return NULL; 1619 } 1620 #ifdef INET6 1621 else if (in6p) { 1622 if ((tp = in6totcpcb(in6p)) == NULL) 1623 return NULL; 1624 } 1625 #endif 1626 else 1627 return NULL; 1628 seq = ntohl(th->th_seq); 1629 if (SEQ_LT(seq, tp->snd_una) || SEQ_GT(seq, tp->snd_max)) 1630 return NULL; 1631 /* 1632 * If the ICMP message advertises a Next-Hop MTU 1633 * equal or larger than the maximum packet size we have 1634 * ever sent, drop the message. 1635 */ 1636 mtu = (u_int)ntohs(icp->icmp_nextmtu); 1637 if (mtu >= tp->t_pmtud_mtu_sent) 1638 return NULL; 1639 if (mtu >= tcp_hdrsz(tp) + tp->t_pmtud_mss_acked) { 1640 /* 1641 * Calculate new MTU, and create corresponding 1642 * route (traditional PMTUD). 1643 */ 1644 tp->t_flags &= ~TF_PMTUD_PEND; 1645 icmp_mtudisc(icp, ip->ip_dst); 1646 } else { 1647 /* 1648 * Record the information got in the ICMP 1649 * message; act on it later. 1650 * If we had already recorded an ICMP message, 1651 * replace the old one only if the new message 1652 * refers to an older TCP segment 1653 */ 1654 if (tp->t_flags & TF_PMTUD_PEND) { 1655 if (SEQ_LT(tp->t_pmtud_th_seq, seq)) 1656 return NULL; 1657 } else 1658 tp->t_flags |= TF_PMTUD_PEND; 1659 tp->t_pmtud_th_seq = seq; 1660 tp->t_pmtud_nextmtu = icp->icmp_nextmtu; 1661 tp->t_pmtud_ip_len = icp->icmp_ip.ip_len; 1662 tp->t_pmtud_ip_hl = icp->icmp_ip.ip_hl; 1663 } 1664 return NULL; 1665 } else if (cmd == PRC_HOSTDEAD) 1666 ip = 0; 1667 else if (errno == 0) 1668 return NULL; 1669 if (ip && ip->ip_v == 4 && sa->sa_family == AF_INET) { 1670 th = (struct tcphdr *)((char *)ip + (ip->ip_hl << 2)); 1671 nmatch = in_pcbnotify(&tcbtable, satocsin(sa)->sin_addr, 1672 th->th_dport, ip->ip_src, th->th_sport, errno, notify); 1673 if (nmatch == 0 && syn_cache_count && 1674 (inetctlerrmap[cmd] == EHOSTUNREACH || 1675 inetctlerrmap[cmd] == ENETUNREACH || 1676 inetctlerrmap[cmd] == EHOSTDOWN)) { 1677 struct sockaddr_in sin; 1678 memset(&sin, 0, sizeof(sin)); 1679 sin.sin_len = sizeof(sin); 1680 sin.sin_family = AF_INET; 1681 sin.sin_port = th->th_sport; 1682 sin.sin_addr = ip->ip_src; 1683 syn_cache_unreach((struct sockaddr *)&sin, sa, th); 1684 } 1685 1686 /* XXX mapped address case */ 1687 } else 1688 in_pcbnotifyall(&tcbtable, satocsin(sa)->sin_addr, errno, 1689 notify); 1690 return NULL; 1691 } 1692 1693 /* 1694 * When a source quench is received, we are being notified of congestion. 1695 * Close the congestion window down to the Loss Window (one segment). 1696 * We will gradually open it again as we proceed. 1697 */ 1698 void 1699 tcp_quench(struct inpcb *inp, int errno) 1700 { 1701 struct tcpcb *tp = intotcpcb(inp); 1702 1703 if (tp) { 1704 tp->snd_cwnd = tp->t_segsz; 1705 tp->t_bytes_acked = 0; 1706 } 1707 } 1708 #endif 1709 1710 #ifdef INET6 1711 void 1712 tcp6_quench(struct in6pcb *in6p, int errno) 1713 { 1714 struct tcpcb *tp = in6totcpcb(in6p); 1715 1716 if (tp) { 1717 tp->snd_cwnd = tp->t_segsz; 1718 tp->t_bytes_acked = 0; 1719 } 1720 } 1721 #endif 1722 1723 #ifdef INET 1724 /* 1725 * Path MTU Discovery handlers. 1726 */ 1727 void 1728 tcp_mtudisc_callback(struct in_addr faddr) 1729 { 1730 #ifdef INET6 1731 struct in6_addr in6; 1732 #endif 1733 1734 in_pcbnotifyall(&tcbtable, faddr, EMSGSIZE, tcp_mtudisc); 1735 #ifdef INET6 1736 memset(&in6, 0, sizeof(in6)); 1737 in6.s6_addr16[5] = 0xffff; 1738 memcpy(&in6.s6_addr32[3], &faddr, sizeof(struct in_addr)); 1739 tcp6_mtudisc_callback(&in6); 1740 #endif 1741 } 1742 1743 /* 1744 * On receipt of path MTU corrections, flush old route and replace it 1745 * with the new one. Retransmit all unacknowledged packets, to ensure 1746 * that all packets will be received. 1747 */ 1748 void 1749 tcp_mtudisc(struct inpcb *inp, int errno) 1750 { 1751 struct tcpcb *tp = intotcpcb(inp); 1752 struct rtentry *rt = in_pcbrtentry(inp); 1753 1754 if (tp != 0) { 1755 if (rt != 0) { 1756 /* 1757 * If this was not a host route, remove and realloc. 1758 */ 1759 if ((rt->rt_flags & RTF_HOST) == 0) { 1760 in_rtchange(inp, errno); 1761 if ((rt = in_pcbrtentry(inp)) == 0) 1762 return; 1763 } 1764 1765 /* 1766 * Slow start out of the error condition. We 1767 * use the MTU because we know it's smaller 1768 * than the previously transmitted segment. 1769 * 1770 * Note: This is more conservative than the 1771 * suggestion in draft-floyd-incr-init-win-03. 1772 */ 1773 if (rt->rt_rmx.rmx_mtu != 0) 1774 tp->snd_cwnd = 1775 TCP_INITIAL_WINDOW(tcp_init_win, 1776 rt->rt_rmx.rmx_mtu); 1777 } 1778 1779 /* 1780 * Resend unacknowledged packets. 1781 */ 1782 tp->snd_nxt = tp->sack_newdata = tp->snd_una; 1783 tcp_output(tp); 1784 } 1785 } 1786 #endif 1787 1788 #ifdef INET6 1789 /* 1790 * Path MTU Discovery handlers. 1791 */ 1792 void 1793 tcp6_mtudisc_callback(struct in6_addr *faddr) 1794 { 1795 struct sockaddr_in6 sin6; 1796 1797 memset(&sin6, 0, sizeof(sin6)); 1798 sin6.sin6_family = AF_INET6; 1799 sin6.sin6_len = sizeof(struct sockaddr_in6); 1800 sin6.sin6_addr = *faddr; 1801 (void) in6_pcbnotify(&tcbtable, (struct sockaddr *)&sin6, 0, 1802 (const struct sockaddr *)&sa6_any, 0, PRC_MSGSIZE, NULL, tcp6_mtudisc); 1803 } 1804 1805 void 1806 tcp6_mtudisc(struct in6pcb *in6p, int errno) 1807 { 1808 struct tcpcb *tp = in6totcpcb(in6p); 1809 struct rtentry *rt = in6_pcbrtentry(in6p); 1810 1811 if (tp != 0) { 1812 if (rt != 0) { 1813 /* 1814 * If this was not a host route, remove and realloc. 1815 */ 1816 if ((rt->rt_flags & RTF_HOST) == 0) { 1817 in6_rtchange(in6p, errno); 1818 if ((rt = in6_pcbrtentry(in6p)) == 0) 1819 return; 1820 } 1821 1822 /* 1823 * Slow start out of the error condition. We 1824 * use the MTU because we know it's smaller 1825 * than the previously transmitted segment. 1826 * 1827 * Note: This is more conservative than the 1828 * suggestion in draft-floyd-incr-init-win-03. 1829 */ 1830 if (rt->rt_rmx.rmx_mtu != 0) 1831 tp->snd_cwnd = 1832 TCP_INITIAL_WINDOW(tcp_init_win, 1833 rt->rt_rmx.rmx_mtu); 1834 } 1835 1836 /* 1837 * Resend unacknowledged packets. 1838 */ 1839 tp->snd_nxt = tp->sack_newdata = tp->snd_una; 1840 tcp_output(tp); 1841 } 1842 } 1843 #endif /* INET6 */ 1844 1845 /* 1846 * Compute the MSS to advertise to the peer. Called only during 1847 * the 3-way handshake. If we are the server (peer initiated 1848 * connection), we are called with a pointer to the interface 1849 * on which the SYN packet arrived. If we are the client (we 1850 * initiated connection), we are called with a pointer to the 1851 * interface out which this connection should go. 1852 * 1853 * NOTE: Do not subtract IP option/extension header size nor IPsec 1854 * header size from MSS advertisement. MSS option must hold the maximum 1855 * segment size we can accept, so it must always be: 1856 * max(if mtu) - ip header - tcp header 1857 */ 1858 u_long 1859 tcp_mss_to_advertise(const struct ifnet *ifp, int af) 1860 { 1861 extern u_long in_maxmtu; 1862 u_long mss = 0; 1863 u_long hdrsiz; 1864 1865 /* 1866 * In order to avoid defeating path MTU discovery on the peer, 1867 * we advertise the max MTU of all attached networks as our MSS, 1868 * per RFC 1191, section 3.1. 1869 * 1870 * We provide the option to advertise just the MTU of 1871 * the interface on which we hope this connection will 1872 * be receiving. If we are responding to a SYN, we 1873 * will have a pretty good idea about this, but when 1874 * initiating a connection there is a bit more doubt. 1875 * 1876 * We also need to ensure that loopback has a large enough 1877 * MSS, as the loopback MTU is never included in in_maxmtu. 1878 */ 1879 1880 if (ifp != NULL) 1881 switch (af) { 1882 case AF_INET: 1883 mss = ifp->if_mtu; 1884 break; 1885 #ifdef INET6 1886 case AF_INET6: 1887 mss = IN6_LINKMTU(ifp); 1888 break; 1889 #endif 1890 } 1891 1892 if (tcp_mss_ifmtu == 0) 1893 switch (af) { 1894 case AF_INET: 1895 mss = max(in_maxmtu, mss); 1896 break; 1897 #ifdef INET6 1898 case AF_INET6: 1899 mss = max(in6_maxmtu, mss); 1900 break; 1901 #endif 1902 } 1903 1904 switch (af) { 1905 case AF_INET: 1906 hdrsiz = sizeof(struct ip); 1907 break; 1908 #ifdef INET6 1909 case AF_INET6: 1910 hdrsiz = sizeof(struct ip6_hdr); 1911 break; 1912 #endif 1913 default: 1914 hdrsiz = 0; 1915 break; 1916 } 1917 hdrsiz += sizeof(struct tcphdr); 1918 if (mss > hdrsiz) 1919 mss -= hdrsiz; 1920 1921 mss = max(tcp_mssdflt, mss); 1922 return (mss); 1923 } 1924 1925 /* 1926 * Set connection variables based on the peer's advertised MSS. 1927 * We are passed the TCPCB for the actual connection. If we 1928 * are the server, we are called by the compressed state engine 1929 * when the 3-way handshake is complete. If we are the client, 1930 * we are called when we receive the SYN,ACK from the server. 1931 * 1932 * NOTE: Our advertised MSS value must be initialized in the TCPCB 1933 * before this routine is called! 1934 */ 1935 void 1936 tcp_mss_from_peer(struct tcpcb *tp, int offer) 1937 { 1938 struct socket *so; 1939 #if defined(RTV_SPIPE) || defined(RTV_SSTHRESH) 1940 struct rtentry *rt; 1941 #endif 1942 u_long bufsize; 1943 int mss; 1944 1945 #ifdef DIAGNOSTIC 1946 if (tp->t_inpcb && tp->t_in6pcb) 1947 panic("tcp_mss_from_peer: both t_inpcb and t_in6pcb are set"); 1948 #endif 1949 so = NULL; 1950 rt = NULL; 1951 #ifdef INET 1952 if (tp->t_inpcb) { 1953 so = tp->t_inpcb->inp_socket; 1954 #if defined(RTV_SPIPE) || defined(RTV_SSTHRESH) 1955 rt = in_pcbrtentry(tp->t_inpcb); 1956 #endif 1957 } 1958 #endif 1959 #ifdef INET6 1960 if (tp->t_in6pcb) { 1961 so = tp->t_in6pcb->in6p_socket; 1962 #if defined(RTV_SPIPE) || defined(RTV_SSTHRESH) 1963 rt = in6_pcbrtentry(tp->t_in6pcb); 1964 #endif 1965 } 1966 #endif 1967 1968 /* 1969 * As per RFC1122, use the default MSS value, unless they 1970 * sent us an offer. Do not accept offers less than 256 bytes. 1971 */ 1972 mss = tcp_mssdflt; 1973 if (offer) 1974 mss = offer; 1975 mss = max(mss, 256); /* sanity */ 1976 tp->t_peermss = mss; 1977 mss -= tcp_optlen(tp); 1978 #ifdef INET 1979 if (tp->t_inpcb) 1980 mss -= ip_optlen(tp->t_inpcb); 1981 #endif 1982 #ifdef INET6 1983 if (tp->t_in6pcb) 1984 mss -= ip6_optlen(tp->t_in6pcb); 1985 #endif 1986 1987 /* 1988 * If there's a pipesize, change the socket buffer to that size. 1989 * Make the socket buffer an integral number of MSS units. If 1990 * the MSS is larger than the socket buffer, artificially decrease 1991 * the MSS. 1992 */ 1993 #ifdef RTV_SPIPE 1994 if (rt != NULL && rt->rt_rmx.rmx_sendpipe != 0) 1995 bufsize = rt->rt_rmx.rmx_sendpipe; 1996 else 1997 #endif 1998 { 1999 KASSERT(so != NULL); 2000 bufsize = so->so_snd.sb_hiwat; 2001 } 2002 if (bufsize < mss) 2003 mss = bufsize; 2004 else { 2005 bufsize = roundup(bufsize, mss); 2006 if (bufsize > sb_max) 2007 bufsize = sb_max; 2008 (void) sbreserve(&so->so_snd, bufsize, so); 2009 } 2010 tp->t_segsz = mss; 2011 2012 #ifdef RTV_SSTHRESH 2013 if (rt != NULL && rt->rt_rmx.rmx_ssthresh) { 2014 /* 2015 * There's some sort of gateway or interface buffer 2016 * limit on the path. Use this to set the slow 2017 * start threshold, but set the threshold to no less 2018 * than 2 * MSS. 2019 */ 2020 tp->snd_ssthresh = max(2 * mss, rt->rt_rmx.rmx_ssthresh); 2021 } 2022 #endif 2023 } 2024 2025 /* 2026 * Processing necessary when a TCP connection is established. 2027 */ 2028 void 2029 tcp_established(struct tcpcb *tp) 2030 { 2031 struct socket *so; 2032 #ifdef RTV_RPIPE 2033 struct rtentry *rt; 2034 #endif 2035 u_long bufsize; 2036 2037 #ifdef DIAGNOSTIC 2038 if (tp->t_inpcb && tp->t_in6pcb) 2039 panic("tcp_established: both t_inpcb and t_in6pcb are set"); 2040 #endif 2041 so = NULL; 2042 rt = NULL; 2043 #ifdef INET 2044 /* This is a while() to reduce the dreadful stairstepping below */ 2045 while (tp->t_inpcb) { 2046 so = tp->t_inpcb->inp_socket; 2047 #if defined(RTV_RPIPE) 2048 rt = in_pcbrtentry(tp->t_inpcb); 2049 #endif 2050 if (__predict_true(tcp_msl_enable)) { 2051 if (tp->t_inpcb->inp_laddr.s_addr == INADDR_LOOPBACK) { 2052 tp->t_msl = tcp_msl_loop ? tcp_msl_loop : (TCPTV_MSL >> 2); 2053 break; 2054 } 2055 2056 if (__predict_false(tcp_rttlocal)) { 2057 /* This may be adjusted by tcp_input */ 2058 tp->t_msl = tcp_msl_local ? tcp_msl_local : (TCPTV_MSL >> 1); 2059 break; 2060 } 2061 if (in_localaddr(tp->t_inpcb->inp_faddr)) { 2062 tp->t_msl = tcp_msl_local ? tcp_msl_local : (TCPTV_MSL >> 1); 2063 break; 2064 } 2065 } 2066 tp->t_msl = tcp_msl_remote ? tcp_msl_remote : TCPTV_MSL; 2067 break; 2068 } 2069 #endif 2070 #ifdef INET6 2071 /* The !tp->t_inpcb lets the compiler know it can't be v4 *and* v6 */ 2072 while (!tp->t_inpcb && tp->t_in6pcb) { 2073 so = tp->t_in6pcb->in6p_socket; 2074 #if defined(RTV_RPIPE) 2075 rt = in6_pcbrtentry(tp->t_in6pcb); 2076 #endif 2077 if (__predict_true(tcp_msl_enable)) { 2078 extern const struct in6_addr in6addr_loopback; 2079 2080 if (IN6_ARE_ADDR_EQUAL(&tp->t_in6pcb->in6p_laddr, 2081 &in6addr_loopback)) { 2082 tp->t_msl = tcp_msl_loop ? tcp_msl_loop : (TCPTV_MSL >> 2); 2083 break; 2084 } 2085 2086 if (__predict_false(tcp_rttlocal)) { 2087 /* This may be adjusted by tcp_input */ 2088 tp->t_msl = tcp_msl_local ? tcp_msl_local : (TCPTV_MSL >> 1); 2089 break; 2090 } 2091 if (in6_localaddr(&tp->t_in6pcb->in6p_faddr)) { 2092 tp->t_msl = tcp_msl_local ? tcp_msl_local : (TCPTV_MSL >> 1); 2093 break; 2094 } 2095 } 2096 tp->t_msl = tcp_msl_remote ? tcp_msl_remote : TCPTV_MSL; 2097 break; 2098 } 2099 #endif 2100 2101 tp->t_state = TCPS_ESTABLISHED; 2102 TCP_TIMER_ARM(tp, TCPT_KEEP, tp->t_keepidle); 2103 2104 #ifdef RTV_RPIPE 2105 if (rt != NULL && rt->rt_rmx.rmx_recvpipe != 0) 2106 bufsize = rt->rt_rmx.rmx_recvpipe; 2107 else 2108 #endif 2109 { 2110 KASSERT(so != NULL); 2111 bufsize = so->so_rcv.sb_hiwat; 2112 } 2113 if (bufsize > tp->t_ourmss) { 2114 bufsize = roundup(bufsize, tp->t_ourmss); 2115 if (bufsize > sb_max) 2116 bufsize = sb_max; 2117 (void) sbreserve(&so->so_rcv, bufsize, so); 2118 } 2119 } 2120 2121 /* 2122 * Check if there's an initial rtt or rttvar. Convert from the 2123 * route-table units to scaled multiples of the slow timeout timer. 2124 * Called only during the 3-way handshake. 2125 */ 2126 void 2127 tcp_rmx_rtt(struct tcpcb *tp) 2128 { 2129 #ifdef RTV_RTT 2130 struct rtentry *rt = NULL; 2131 int rtt; 2132 2133 #ifdef DIAGNOSTIC 2134 if (tp->t_inpcb && tp->t_in6pcb) 2135 panic("tcp_rmx_rtt: both t_inpcb and t_in6pcb are set"); 2136 #endif 2137 #ifdef INET 2138 if (tp->t_inpcb) 2139 rt = in_pcbrtentry(tp->t_inpcb); 2140 #endif 2141 #ifdef INET6 2142 if (tp->t_in6pcb) 2143 rt = in6_pcbrtentry(tp->t_in6pcb); 2144 #endif 2145 if (rt == NULL) 2146 return; 2147 2148 if (tp->t_srtt == 0 && (rtt = rt->rt_rmx.rmx_rtt)) { 2149 /* 2150 * XXX The lock bit for MTU indicates that the value 2151 * is also a minimum value; this is subject to time. 2152 */ 2153 if (rt->rt_rmx.rmx_locks & RTV_RTT) 2154 TCPT_RANGESET(tp->t_rttmin, 2155 rtt / (RTM_RTTUNIT / PR_SLOWHZ), 2156 TCPTV_MIN, TCPTV_REXMTMAX); 2157 tp->t_srtt = rtt / 2158 ((RTM_RTTUNIT / PR_SLOWHZ) >> (TCP_RTT_SHIFT + 2)); 2159 if (rt->rt_rmx.rmx_rttvar) { 2160 tp->t_rttvar = rt->rt_rmx.rmx_rttvar / 2161 ((RTM_RTTUNIT / PR_SLOWHZ) >> 2162 (TCP_RTTVAR_SHIFT + 2)); 2163 } else { 2164 /* Default variation is +- 1 rtt */ 2165 tp->t_rttvar = 2166 tp->t_srtt >> (TCP_RTT_SHIFT - TCP_RTTVAR_SHIFT); 2167 } 2168 TCPT_RANGESET(tp->t_rxtcur, 2169 ((tp->t_srtt >> 2) + tp->t_rttvar) >> (1 + 2), 2170 tp->t_rttmin, TCPTV_REXMTMAX); 2171 } 2172 #endif 2173 } 2174 2175 tcp_seq tcp_iss_seq = 0; /* tcp initial seq # */ 2176 u_int8_t tcp_iss_secret[16]; /* 128 bits; should be plenty */ 2177 2178 /* 2179 * Get a new sequence value given a tcp control block 2180 */ 2181 tcp_seq 2182 tcp_new_iss(struct tcpcb *tp, tcp_seq addin) 2183 { 2184 2185 #ifdef INET 2186 if (tp->t_inpcb != NULL) { 2187 return (tcp_new_iss1(&tp->t_inpcb->inp_laddr, 2188 &tp->t_inpcb->inp_faddr, tp->t_inpcb->inp_lport, 2189 tp->t_inpcb->inp_fport, sizeof(tp->t_inpcb->inp_laddr), 2190 addin)); 2191 } 2192 #endif 2193 #ifdef INET6 2194 if (tp->t_in6pcb != NULL) { 2195 return (tcp_new_iss1(&tp->t_in6pcb->in6p_laddr, 2196 &tp->t_in6pcb->in6p_faddr, tp->t_in6pcb->in6p_lport, 2197 tp->t_in6pcb->in6p_fport, sizeof(tp->t_in6pcb->in6p_laddr), 2198 addin)); 2199 } 2200 #endif 2201 /* Not possible. */ 2202 panic("tcp_new_iss"); 2203 } 2204 2205 /* 2206 * This routine actually generates a new TCP initial sequence number. 2207 */ 2208 tcp_seq 2209 tcp_new_iss1(void *laddr, void *faddr, u_int16_t lport, u_int16_t fport, 2210 size_t addrsz, tcp_seq addin) 2211 { 2212 tcp_seq tcp_iss; 2213 2214 static bool tcp_iss_gotten_secret; 2215 2216 /* 2217 * If we haven't been here before, initialize our cryptographic 2218 * hash secret. 2219 */ 2220 if (tcp_iss_gotten_secret == false) { 2221 cprng_strong(kern_cprng, 2222 tcp_iss_secret, sizeof(tcp_iss_secret), 0); 2223 tcp_iss_gotten_secret = true; 2224 } 2225 2226 if (tcp_do_rfc1948) { 2227 MD5_CTX ctx; 2228 u_int8_t hash[16]; /* XXX MD5 knowledge */ 2229 2230 /* 2231 * Compute the base value of the ISS. It is a hash 2232 * of (saddr, sport, daddr, dport, secret). 2233 */ 2234 MD5Init(&ctx); 2235 2236 MD5Update(&ctx, (u_char *) laddr, addrsz); 2237 MD5Update(&ctx, (u_char *) &lport, sizeof(lport)); 2238 2239 MD5Update(&ctx, (u_char *) faddr, addrsz); 2240 MD5Update(&ctx, (u_char *) &fport, sizeof(fport)); 2241 2242 MD5Update(&ctx, tcp_iss_secret, sizeof(tcp_iss_secret)); 2243 2244 MD5Final(hash, &ctx); 2245 2246 memcpy(&tcp_iss, hash, sizeof(tcp_iss)); 2247 2248 /* 2249 * Now increment our "timer", and add it in to 2250 * the computed value. 2251 * 2252 * XXX Use `addin'? 2253 * XXX TCP_ISSINCR too large to use? 2254 */ 2255 tcp_iss_seq += TCP_ISSINCR; 2256 #ifdef TCPISS_DEBUG 2257 printf("ISS hash 0x%08x, ", tcp_iss); 2258 #endif 2259 tcp_iss += tcp_iss_seq + addin; 2260 #ifdef TCPISS_DEBUG 2261 printf("new ISS 0x%08x\n", tcp_iss); 2262 #endif 2263 } else { 2264 /* 2265 * Randomize. 2266 */ 2267 tcp_iss = cprng_fast32(); 2268 2269 /* 2270 * If we were asked to add some amount to a known value, 2271 * we will take a random value obtained above, mask off 2272 * the upper bits, and add in the known value. We also 2273 * add in a constant to ensure that we are at least a 2274 * certain distance from the original value. 2275 * 2276 * This is used when an old connection is in timed wait 2277 * and we have a new one coming in, for instance. 2278 */ 2279 if (addin != 0) { 2280 #ifdef TCPISS_DEBUG 2281 printf("Random %08x, ", tcp_iss); 2282 #endif 2283 tcp_iss &= TCP_ISS_RANDOM_MASK; 2284 tcp_iss += addin + TCP_ISSINCR; 2285 #ifdef TCPISS_DEBUG 2286 printf("Old ISS %08x, ISS %08x\n", addin, tcp_iss); 2287 #endif 2288 } else { 2289 tcp_iss &= TCP_ISS_RANDOM_MASK; 2290 tcp_iss += tcp_iss_seq; 2291 tcp_iss_seq += TCP_ISSINCR; 2292 #ifdef TCPISS_DEBUG 2293 printf("ISS %08x\n", tcp_iss); 2294 #endif 2295 } 2296 } 2297 2298 if (tcp_compat_42) { 2299 /* 2300 * Limit it to the positive range for really old TCP 2301 * implementations. 2302 * Just AND off the top bit instead of checking if 2303 * is set first - saves a branch 50% of the time. 2304 */ 2305 tcp_iss &= 0x7fffffff; /* XXX */ 2306 } 2307 2308 return (tcp_iss); 2309 } 2310 2311 #if defined(KAME_IPSEC) || defined(FAST_IPSEC) 2312 /* compute ESP/AH header size for TCP, including outer IP header. */ 2313 size_t 2314 ipsec4_hdrsiz_tcp(struct tcpcb *tp) 2315 { 2316 struct inpcb *inp; 2317 size_t hdrsiz; 2318 2319 /* XXX mapped addr case (tp->t_in6pcb) */ 2320 if (!tp || !tp->t_template || !(inp = tp->t_inpcb)) 2321 return 0; 2322 switch (tp->t_family) { 2323 case AF_INET: 2324 /* XXX: should use currect direction. */ 2325 hdrsiz = ipsec4_hdrsiz(tp->t_template, IPSEC_DIR_OUTBOUND, inp); 2326 break; 2327 default: 2328 hdrsiz = 0; 2329 break; 2330 } 2331 2332 return hdrsiz; 2333 } 2334 2335 #ifdef INET6 2336 size_t 2337 ipsec6_hdrsiz_tcp(struct tcpcb *tp) 2338 { 2339 struct in6pcb *in6p; 2340 size_t hdrsiz; 2341 2342 if (!tp || !tp->t_template || !(in6p = tp->t_in6pcb)) 2343 return 0; 2344 switch (tp->t_family) { 2345 case AF_INET6: 2346 /* XXX: should use currect direction. */ 2347 hdrsiz = ipsec6_hdrsiz(tp->t_template, IPSEC_DIR_OUTBOUND, in6p); 2348 break; 2349 case AF_INET: 2350 /* mapped address case - tricky */ 2351 default: 2352 hdrsiz = 0; 2353 break; 2354 } 2355 2356 return hdrsiz; 2357 } 2358 #endif 2359 #endif /*IPSEC*/ 2360 2361 /* 2362 * Determine the length of the TCP options for this connection. 2363 * 2364 * XXX: What do we do for SACK, when we add that? Just reserve 2365 * all of the space? Otherwise we can't exactly be incrementing 2366 * cwnd by an amount that varies depending on the amount we last 2367 * had to SACK! 2368 */ 2369 2370 u_int 2371 tcp_optlen(struct tcpcb *tp) 2372 { 2373 u_int optlen; 2374 2375 optlen = 0; 2376 if ((tp->t_flags & (TF_REQ_TSTMP|TF_RCVD_TSTMP|TF_NOOPT)) == 2377 (TF_REQ_TSTMP | TF_RCVD_TSTMP)) 2378 optlen += TCPOLEN_TSTAMP_APPA; 2379 2380 #ifdef TCP_SIGNATURE 2381 if (tp->t_flags & TF_SIGNATURE) 2382 optlen += TCPOLEN_SIGNATURE + 2; 2383 #endif /* TCP_SIGNATURE */ 2384 2385 return optlen; 2386 } 2387 2388 u_int 2389 tcp_hdrsz(struct tcpcb *tp) 2390 { 2391 u_int hlen; 2392 2393 switch (tp->t_family) { 2394 #ifdef INET6 2395 case AF_INET6: 2396 hlen = sizeof(struct ip6_hdr); 2397 break; 2398 #endif 2399 case AF_INET: 2400 hlen = sizeof(struct ip); 2401 break; 2402 default: 2403 hlen = 0; 2404 break; 2405 } 2406 hlen += sizeof(struct tcphdr); 2407 2408 if ((tp->t_flags & (TF_REQ_TSTMP|TF_NOOPT)) == TF_REQ_TSTMP && 2409 (tp->t_flags & TF_RCVD_TSTMP) == TF_RCVD_TSTMP) 2410 hlen += TCPOLEN_TSTAMP_APPA; 2411 #ifdef TCP_SIGNATURE 2412 if (tp->t_flags & TF_SIGNATURE) 2413 hlen += TCPOLEN_SIGLEN; 2414 #endif 2415 return hlen; 2416 } 2417 2418 void 2419 tcp_statinc(u_int stat) 2420 { 2421 2422 KASSERT(stat < TCP_NSTATS); 2423 TCP_STATINC(stat); 2424 } 2425 2426 void 2427 tcp_statadd(u_int stat, uint64_t val) 2428 { 2429 2430 KASSERT(stat < TCP_NSTATS); 2431 TCP_STATADD(stat, val); 2432 } 2433