tcp_subr.c revision 1.242
1 /* $NetBSD: tcp_subr.c,v 1.242 2011/10/31 12:56:45 yamt 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 1.242 2011/10/31 12:56:45 yamt 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 #include "rnd.h" 102 103 #include <sys/param.h> 104 #include <sys/proc.h> 105 #include <sys/systm.h> 106 #include <sys/malloc.h> 107 #include <sys/mbuf.h> 108 #include <sys/socket.h> 109 #include <sys/socketvar.h> 110 #include <sys/protosw.h> 111 #include <sys/errno.h> 112 #include <sys/kernel.h> 113 #include <sys/pool.h> 114 #if NRND > 0 115 #include <sys/md5.h> 116 #include <sys/rnd.h> 117 #endif 118 119 #include <net/route.h> 120 #include <net/if.h> 121 122 #include <netinet/in.h> 123 #include <netinet/in_systm.h> 124 #include <netinet/ip.h> 125 #include <netinet/in_pcb.h> 126 #include <netinet/ip_var.h> 127 #include <netinet/ip_icmp.h> 128 129 #ifdef INET6 130 #ifndef INET 131 #include <netinet/in.h> 132 #endif 133 #include <netinet/ip6.h> 134 #include <netinet6/in6_pcb.h> 135 #include <netinet6/ip6_var.h> 136 #include <netinet6/in6_var.h> 137 #include <netinet6/ip6protosw.h> 138 #include <netinet/icmp6.h> 139 #include <netinet6/nd6.h> 140 #endif 141 142 #include <netinet/tcp.h> 143 #include <netinet/tcp_fsm.h> 144 #include <netinet/tcp_seq.h> 145 #include <netinet/tcp_timer.h> 146 #include <netinet/tcp_var.h> 147 #include <netinet/tcp_vtw.h> 148 #include <netinet/tcp_private.h> 149 #include <netinet/tcp_congctl.h> 150 #include <netinet/tcpip.h> 151 152 #ifdef IPSEC 153 #include <netinet6/ipsec.h> 154 #include <netkey/key.h> 155 #endif /*IPSEC*/ 156 157 #ifdef FAST_IPSEC 158 #include <netipsec/ipsec.h> 159 #include <netipsec/xform.h> 160 #ifdef INET6 161 #include <netipsec/ipsec6.h> 162 #endif 163 #include <netipsec/key.h> 164 #endif /* FAST_IPSEC*/ 165 166 167 struct inpcbtable tcbtable; /* head of queue of active tcpcb's */ 168 u_int32_t tcp_now; /* slow ticks, for RFC 1323 timestamps */ 169 170 percpu_t *tcpstat_percpu; 171 172 /* patchable/settable parameters for tcp */ 173 int tcp_mssdflt = TCP_MSS; 174 int tcp_minmss = TCP_MINMSS; 175 int tcp_rttdflt = TCPTV_SRTTDFLT / PR_SLOWHZ; 176 int tcp_do_rfc1323 = 1; /* window scaling / timestamps (obsolete) */ 177 #if NRND > 0 178 int tcp_do_rfc1948 = 0; /* ISS by cryptographic hash */ 179 #endif 180 int tcp_do_sack = 1; /* selective acknowledgement */ 181 int tcp_do_win_scale = 1; /* RFC1323 window scaling */ 182 int tcp_do_timestamps = 1; /* RFC1323 timestamps */ 183 int tcp_ack_on_push = 0; /* set to enable immediate ACK-on-PUSH */ 184 int tcp_do_ecn = 0; /* Explicit Congestion Notification */ 185 #ifndef TCP_INIT_WIN 186 #define TCP_INIT_WIN 0 /* initial slow start window */ 187 #endif 188 #ifndef TCP_INIT_WIN_LOCAL 189 #define TCP_INIT_WIN_LOCAL 4 /* initial slow start window for local nets */ 190 #endif 191 int tcp_init_win = TCP_INIT_WIN; 192 int tcp_init_win_local = TCP_INIT_WIN_LOCAL; 193 int tcp_mss_ifmtu = 0; 194 #ifdef TCP_COMPAT_42 195 int tcp_compat_42 = 1; 196 #else 197 int tcp_compat_42 = 0; 198 #endif 199 int tcp_rst_ppslim = 100; /* 100pps */ 200 int tcp_ackdrop_ppslim = 100; /* 100pps */ 201 int tcp_do_loopback_cksum = 0; 202 int tcp_do_abc = 1; /* RFC3465 Appropriate byte counting. */ 203 int tcp_abc_aggressive = 1; /* 1: L=2*SMSS 0: L=1*SMSS */ 204 int tcp_sack_tp_maxholes = 32; 205 int tcp_sack_globalmaxholes = 1024; 206 int tcp_sack_globalholes = 0; 207 int tcp_ecn_maxretries = 1; 208 int tcp_msl_enable = 1; /* enable TIME_WAIT truncation */ 209 int tcp_msl_loop = PR_SLOWHZ; /* MSL for loopback */ 210 int tcp_msl_local = 5 * PR_SLOWHZ; /* MSL for 'local' */ 211 int tcp_msl_remote = TCPTV_MSL; /* MSL otherwise */ 212 int tcp_msl_remote_threshold = TCPTV_SRTTDFLT; /* RTT threshold */ 213 int tcp_rttlocal = 0; /* Use RTT to decide who's 'local' */ 214 215 int tcp4_vtw_enable = 0; /* 1 to enable */ 216 int tcp6_vtw_enable = 0; /* 1 to enable */ 217 int tcp_vtw_was_enabled = 0; 218 int tcp_vtw_entries = 1 << 16; /* 64K vestigial TIME_WAIT entries */ 219 220 /* tcb hash */ 221 #ifndef TCBHASHSIZE 222 #define TCBHASHSIZE 128 223 #endif 224 int tcbhashsize = TCBHASHSIZE; 225 226 /* syn hash parameters */ 227 #define TCP_SYN_HASH_SIZE 293 228 #define TCP_SYN_BUCKET_SIZE 35 229 int tcp_syn_cache_size = TCP_SYN_HASH_SIZE; 230 int tcp_syn_cache_limit = TCP_SYN_HASH_SIZE*TCP_SYN_BUCKET_SIZE; 231 int tcp_syn_bucket_limit = 3*TCP_SYN_BUCKET_SIZE; 232 struct syn_cache_head tcp_syn_cache[TCP_SYN_HASH_SIZE]; 233 234 int tcp_freeq(struct tcpcb *); 235 236 #ifdef INET 237 void tcp_mtudisc_callback(struct in_addr); 238 #endif 239 #ifdef INET6 240 void tcp6_mtudisc_callback(struct in6_addr *); 241 #endif 242 243 #ifdef INET6 244 void tcp6_mtudisc(struct in6pcb *, int); 245 #endif 246 247 static struct pool tcpcb_pool; 248 249 static int tcp_drainwanted; 250 251 #ifdef TCP_CSUM_COUNTERS 252 #include <sys/device.h> 253 254 #if defined(INET) 255 struct evcnt tcp_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 256 NULL, "tcp", "hwcsum bad"); 257 struct evcnt tcp_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 258 NULL, "tcp", "hwcsum ok"); 259 struct evcnt tcp_hwcsum_data = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 260 NULL, "tcp", "hwcsum data"); 261 struct evcnt tcp_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 262 NULL, "tcp", "swcsum"); 263 264 EVCNT_ATTACH_STATIC(tcp_hwcsum_bad); 265 EVCNT_ATTACH_STATIC(tcp_hwcsum_ok); 266 EVCNT_ATTACH_STATIC(tcp_hwcsum_data); 267 EVCNT_ATTACH_STATIC(tcp_swcsum); 268 #endif /* defined(INET) */ 269 270 #if defined(INET6) 271 struct evcnt tcp6_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 272 NULL, "tcp6", "hwcsum bad"); 273 struct evcnt tcp6_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 274 NULL, "tcp6", "hwcsum ok"); 275 struct evcnt tcp6_hwcsum_data = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 276 NULL, "tcp6", "hwcsum data"); 277 struct evcnt tcp6_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 278 NULL, "tcp6", "swcsum"); 279 280 EVCNT_ATTACH_STATIC(tcp6_hwcsum_bad); 281 EVCNT_ATTACH_STATIC(tcp6_hwcsum_ok); 282 EVCNT_ATTACH_STATIC(tcp6_hwcsum_data); 283 EVCNT_ATTACH_STATIC(tcp6_swcsum); 284 #endif /* defined(INET6) */ 285 #endif /* TCP_CSUM_COUNTERS */ 286 287 288 #ifdef TCP_OUTPUT_COUNTERS 289 #include <sys/device.h> 290 291 struct evcnt tcp_output_bigheader = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 292 NULL, "tcp", "output big header"); 293 struct evcnt tcp_output_predict_hit = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 294 NULL, "tcp", "output predict hit"); 295 struct evcnt tcp_output_predict_miss = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 296 NULL, "tcp", "output predict miss"); 297 struct evcnt tcp_output_copysmall = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 298 NULL, "tcp", "output copy small"); 299 struct evcnt tcp_output_copybig = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 300 NULL, "tcp", "output copy big"); 301 struct evcnt tcp_output_refbig = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 302 NULL, "tcp", "output reference big"); 303 304 EVCNT_ATTACH_STATIC(tcp_output_bigheader); 305 EVCNT_ATTACH_STATIC(tcp_output_predict_hit); 306 EVCNT_ATTACH_STATIC(tcp_output_predict_miss); 307 EVCNT_ATTACH_STATIC(tcp_output_copysmall); 308 EVCNT_ATTACH_STATIC(tcp_output_copybig); 309 EVCNT_ATTACH_STATIC(tcp_output_refbig); 310 311 #endif /* TCP_OUTPUT_COUNTERS */ 312 313 #ifdef TCP_REASS_COUNTERS 314 #include <sys/device.h> 315 316 struct evcnt tcp_reass_ = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 317 NULL, "tcp_reass", "calls"); 318 struct evcnt tcp_reass_empty = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 319 &tcp_reass_, "tcp_reass", "insert into empty queue"); 320 struct evcnt tcp_reass_iteration[8] = { 321 EVCNT_INITIALIZER(EVCNT_TYPE_MISC, &tcp_reass_, "tcp_reass", ">7 iterations"), 322 EVCNT_INITIALIZER(EVCNT_TYPE_MISC, &tcp_reass_, "tcp_reass", "1 iteration"), 323 EVCNT_INITIALIZER(EVCNT_TYPE_MISC, &tcp_reass_, "tcp_reass", "2 iterations"), 324 EVCNT_INITIALIZER(EVCNT_TYPE_MISC, &tcp_reass_, "tcp_reass", "3 iterations"), 325 EVCNT_INITIALIZER(EVCNT_TYPE_MISC, &tcp_reass_, "tcp_reass", "4 iterations"), 326 EVCNT_INITIALIZER(EVCNT_TYPE_MISC, &tcp_reass_, "tcp_reass", "5 iterations"), 327 EVCNT_INITIALIZER(EVCNT_TYPE_MISC, &tcp_reass_, "tcp_reass", "6 iterations"), 328 EVCNT_INITIALIZER(EVCNT_TYPE_MISC, &tcp_reass_, "tcp_reass", "7 iterations"), 329 }; 330 struct evcnt tcp_reass_prependfirst = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 331 &tcp_reass_, "tcp_reass", "prepend to first"); 332 struct evcnt tcp_reass_prepend = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 333 &tcp_reass_, "tcp_reass", "prepend"); 334 struct evcnt tcp_reass_insert = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 335 &tcp_reass_, "tcp_reass", "insert"); 336 struct evcnt tcp_reass_inserttail = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 337 &tcp_reass_, "tcp_reass", "insert at tail"); 338 struct evcnt tcp_reass_append = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 339 &tcp_reass_, "tcp_reass", "append"); 340 struct evcnt tcp_reass_appendtail = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 341 &tcp_reass_, "tcp_reass", "append to tail fragment"); 342 struct evcnt tcp_reass_overlaptail = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 343 &tcp_reass_, "tcp_reass", "overlap at end"); 344 struct evcnt tcp_reass_overlapfront = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 345 &tcp_reass_, "tcp_reass", "overlap at start"); 346 struct evcnt tcp_reass_segdup = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 347 &tcp_reass_, "tcp_reass", "duplicate segment"); 348 struct evcnt tcp_reass_fragdup = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 349 &tcp_reass_, "tcp_reass", "duplicate fragment"); 350 351 EVCNT_ATTACH_STATIC(tcp_reass_); 352 EVCNT_ATTACH_STATIC(tcp_reass_empty); 353 EVCNT_ATTACH_STATIC2(tcp_reass_iteration, 0); 354 EVCNT_ATTACH_STATIC2(tcp_reass_iteration, 1); 355 EVCNT_ATTACH_STATIC2(tcp_reass_iteration, 2); 356 EVCNT_ATTACH_STATIC2(tcp_reass_iteration, 3); 357 EVCNT_ATTACH_STATIC2(tcp_reass_iteration, 4); 358 EVCNT_ATTACH_STATIC2(tcp_reass_iteration, 5); 359 EVCNT_ATTACH_STATIC2(tcp_reass_iteration, 6); 360 EVCNT_ATTACH_STATIC2(tcp_reass_iteration, 7); 361 EVCNT_ATTACH_STATIC(tcp_reass_prependfirst); 362 EVCNT_ATTACH_STATIC(tcp_reass_prepend); 363 EVCNT_ATTACH_STATIC(tcp_reass_insert); 364 EVCNT_ATTACH_STATIC(tcp_reass_inserttail); 365 EVCNT_ATTACH_STATIC(tcp_reass_append); 366 EVCNT_ATTACH_STATIC(tcp_reass_appendtail); 367 EVCNT_ATTACH_STATIC(tcp_reass_overlaptail); 368 EVCNT_ATTACH_STATIC(tcp_reass_overlapfront); 369 EVCNT_ATTACH_STATIC(tcp_reass_segdup); 370 EVCNT_ATTACH_STATIC(tcp_reass_fragdup); 371 372 #endif /* TCP_REASS_COUNTERS */ 373 374 #ifdef MBUFTRACE 375 struct mowner tcp_mowner = MOWNER_INIT("tcp", ""); 376 struct mowner tcp_rx_mowner = MOWNER_INIT("tcp", "rx"); 377 struct mowner tcp_tx_mowner = MOWNER_INIT("tcp", "tx"); 378 struct mowner tcp_sock_mowner = MOWNER_INIT("tcp", "sock"); 379 struct mowner tcp_sock_rx_mowner = MOWNER_INIT("tcp", "sock rx"); 380 struct mowner tcp_sock_tx_mowner = MOWNER_INIT("tcp", "sock tx"); 381 #endif 382 383 /* 384 * Tcp initialization 385 */ 386 void 387 tcp_init(void) 388 { 389 int hlen; 390 391 in_pcbinit(&tcbtable, tcbhashsize, tcbhashsize); 392 pool_init(&tcpcb_pool, sizeof(struct tcpcb), 0, 0, 0, "tcpcbpl", 393 NULL, IPL_SOFTNET); 394 395 hlen = sizeof(struct ip) + sizeof(struct tcphdr); 396 #ifdef INET6 397 if (sizeof(struct ip) < sizeof(struct ip6_hdr)) 398 hlen = sizeof(struct ip6_hdr) + sizeof(struct tcphdr); 399 #endif 400 if (max_protohdr < hlen) 401 max_protohdr = hlen; 402 if (max_linkhdr + hlen > MHLEN) 403 panic("tcp_init"); 404 405 #ifdef INET 406 icmp_mtudisc_callback_register(tcp_mtudisc_callback); 407 #endif 408 #ifdef INET6 409 icmp6_mtudisc_callback_register(tcp6_mtudisc_callback); 410 #endif 411 412 tcp_usrreq_init(); 413 414 /* Initialize timer state. */ 415 tcp_timer_init(); 416 417 /* Initialize the compressed state engine. */ 418 syn_cache_init(); 419 420 /* Initialize the congestion control algorithms. */ 421 tcp_congctl_init(); 422 423 /* Initialize the TCPCB template. */ 424 tcp_tcpcb_template(); 425 426 /* Initialize reassembly queue */ 427 tcpipqent_init(); 428 429 /* SACK */ 430 tcp_sack_init(); 431 432 MOWNER_ATTACH(&tcp_tx_mowner); 433 MOWNER_ATTACH(&tcp_rx_mowner); 434 MOWNER_ATTACH(&tcp_reass_mowner); 435 MOWNER_ATTACH(&tcp_sock_mowner); 436 MOWNER_ATTACH(&tcp_sock_tx_mowner); 437 MOWNER_ATTACH(&tcp_sock_rx_mowner); 438 MOWNER_ATTACH(&tcp_mowner); 439 440 tcpstat_percpu = percpu_alloc(sizeof(uint64_t) * TCP_NSTATS); 441 442 vtw_earlyinit(); 443 } 444 445 /* 446 * Create template to be used to send tcp packets on a connection. 447 * Call after host entry created, allocates an mbuf and fills 448 * in a skeletal tcp/ip header, minimizing the amount of work 449 * necessary when the connection is used. 450 */ 451 struct mbuf * 452 tcp_template(struct tcpcb *tp) 453 { 454 struct inpcb *inp = tp->t_inpcb; 455 #ifdef INET6 456 struct in6pcb *in6p = tp->t_in6pcb; 457 #endif 458 struct tcphdr *n; 459 struct mbuf *m; 460 int hlen; 461 462 switch (tp->t_family) { 463 case AF_INET: 464 hlen = sizeof(struct ip); 465 if (inp) 466 break; 467 #ifdef INET6 468 if (in6p) { 469 /* mapped addr case */ 470 if (IN6_IS_ADDR_V4MAPPED(&in6p->in6p_laddr) 471 && IN6_IS_ADDR_V4MAPPED(&in6p->in6p_faddr)) 472 break; 473 } 474 #endif 475 return NULL; /*EINVAL*/ 476 #ifdef INET6 477 case AF_INET6: 478 hlen = sizeof(struct ip6_hdr); 479 if (in6p) { 480 /* more sainty check? */ 481 break; 482 } 483 return NULL; /*EINVAL*/ 484 #endif 485 default: 486 hlen = 0; /*pacify gcc*/ 487 return NULL; /*EAFNOSUPPORT*/ 488 } 489 #ifdef DIAGNOSTIC 490 if (hlen + sizeof(struct tcphdr) > MCLBYTES) 491 panic("mclbytes too small for t_template"); 492 #endif 493 m = tp->t_template; 494 if (m && m->m_len == hlen + sizeof(struct tcphdr)) 495 ; 496 else { 497 if (m) 498 m_freem(m); 499 m = tp->t_template = NULL; 500 MGETHDR(m, M_DONTWAIT, MT_HEADER); 501 if (m && hlen + sizeof(struct tcphdr) > MHLEN) { 502 MCLGET(m, M_DONTWAIT); 503 if ((m->m_flags & M_EXT) == 0) { 504 m_free(m); 505 m = NULL; 506 } 507 } 508 if (m == NULL) 509 return NULL; 510 MCLAIM(m, &tcp_mowner); 511 m->m_pkthdr.len = m->m_len = hlen + sizeof(struct tcphdr); 512 } 513 514 memset(mtod(m, void *), 0, m->m_len); 515 516 n = (struct tcphdr *)(mtod(m, char *) + hlen); 517 518 switch (tp->t_family) { 519 case AF_INET: 520 { 521 struct ipovly *ipov; 522 mtod(m, struct ip *)->ip_v = 4; 523 mtod(m, struct ip *)->ip_hl = hlen >> 2; 524 ipov = mtod(m, struct ipovly *); 525 ipov->ih_pr = IPPROTO_TCP; 526 ipov->ih_len = htons(sizeof(struct tcphdr)); 527 if (inp) { 528 ipov->ih_src = inp->inp_laddr; 529 ipov->ih_dst = inp->inp_faddr; 530 } 531 #ifdef INET6 532 else if (in6p) { 533 /* mapped addr case */ 534 bcopy(&in6p->in6p_laddr.s6_addr32[3], &ipov->ih_src, 535 sizeof(ipov->ih_src)); 536 bcopy(&in6p->in6p_faddr.s6_addr32[3], &ipov->ih_dst, 537 sizeof(ipov->ih_dst)); 538 } 539 #endif 540 /* 541 * Compute the pseudo-header portion of the checksum 542 * now. We incrementally add in the TCP option and 543 * payload lengths later, and then compute the TCP 544 * checksum right before the packet is sent off onto 545 * the wire. 546 */ 547 n->th_sum = in_cksum_phdr(ipov->ih_src.s_addr, 548 ipov->ih_dst.s_addr, 549 htons(sizeof(struct tcphdr) + IPPROTO_TCP)); 550 break; 551 } 552 #ifdef INET6 553 case AF_INET6: 554 { 555 struct ip6_hdr *ip6; 556 mtod(m, struct ip *)->ip_v = 6; 557 ip6 = mtod(m, struct ip6_hdr *); 558 ip6->ip6_nxt = IPPROTO_TCP; 559 ip6->ip6_plen = htons(sizeof(struct tcphdr)); 560 ip6->ip6_src = in6p->in6p_laddr; 561 ip6->ip6_dst = in6p->in6p_faddr; 562 ip6->ip6_flow = in6p->in6p_flowinfo & IPV6_FLOWINFO_MASK; 563 if (ip6_auto_flowlabel) { 564 ip6->ip6_flow &= ~IPV6_FLOWLABEL_MASK; 565 ip6->ip6_flow |= 566 (htonl(ip6_randomflowlabel()) & IPV6_FLOWLABEL_MASK); 567 } 568 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 569 ip6->ip6_vfc |= IPV6_VERSION; 570 571 /* 572 * Compute the pseudo-header portion of the checksum 573 * now. We incrementally add in the TCP option and 574 * payload lengths later, and then compute the TCP 575 * checksum right before the packet is sent off onto 576 * the wire. 577 */ 578 n->th_sum = in6_cksum_phdr(&in6p->in6p_laddr, 579 &in6p->in6p_faddr, htonl(sizeof(struct tcphdr)), 580 htonl(IPPROTO_TCP)); 581 break; 582 } 583 #endif 584 } 585 if (inp) { 586 n->th_sport = inp->inp_lport; 587 n->th_dport = inp->inp_fport; 588 } 589 #ifdef INET6 590 else if (in6p) { 591 n->th_sport = in6p->in6p_lport; 592 n->th_dport = in6p->in6p_fport; 593 } 594 #endif 595 n->th_seq = 0; 596 n->th_ack = 0; 597 n->th_x2 = 0; 598 n->th_off = 5; 599 n->th_flags = 0; 600 n->th_win = 0; 601 n->th_urp = 0; 602 return (m); 603 } 604 605 /* 606 * Send a single message to the TCP at address specified by 607 * the given TCP/IP header. If m == 0, then we make a copy 608 * of the tcpiphdr at ti and send directly to the addressed host. 609 * This is used to force keep alive messages out using the TCP 610 * template for a connection tp->t_template. If flags are given 611 * then we send a message back to the TCP which originated the 612 * segment ti, and discard the mbuf containing it and any other 613 * attached mbufs. 614 * 615 * In any case the ack and sequence number of the transmitted 616 * segment are as specified by the parameters. 617 */ 618 int 619 tcp_respond(struct tcpcb *tp, struct mbuf *template, struct mbuf *m, 620 struct tcphdr *th0, tcp_seq ack, tcp_seq seq, int flags) 621 { 622 #ifdef INET6 623 struct rtentry *rt; 624 #endif 625 struct route *ro; 626 int error, tlen, win = 0; 627 int hlen; 628 struct ip *ip; 629 #ifdef INET6 630 struct ip6_hdr *ip6; 631 #endif 632 int family; /* family on packet, not inpcb/in6pcb! */ 633 struct tcphdr *th; 634 struct socket *so; 635 636 if (tp != NULL && (flags & TH_RST) == 0) { 637 #ifdef DIAGNOSTIC 638 if (tp->t_inpcb && tp->t_in6pcb) 639 panic("tcp_respond: both t_inpcb and t_in6pcb are set"); 640 #endif 641 #ifdef INET 642 if (tp->t_inpcb) 643 win = sbspace(&tp->t_inpcb->inp_socket->so_rcv); 644 #endif 645 #ifdef INET6 646 if (tp->t_in6pcb) 647 win = sbspace(&tp->t_in6pcb->in6p_socket->so_rcv); 648 #endif 649 } 650 651 th = NULL; /* Quell uninitialized warning */ 652 ip = NULL; 653 #ifdef INET6 654 ip6 = NULL; 655 #endif 656 if (m == 0) { 657 if (!template) 658 return EINVAL; 659 660 /* get family information from template */ 661 switch (mtod(template, struct ip *)->ip_v) { 662 case 4: 663 family = AF_INET; 664 hlen = sizeof(struct ip); 665 break; 666 #ifdef INET6 667 case 6: 668 family = AF_INET6; 669 hlen = sizeof(struct ip6_hdr); 670 break; 671 #endif 672 default: 673 return EAFNOSUPPORT; 674 } 675 676 MGETHDR(m, M_DONTWAIT, MT_HEADER); 677 if (m) { 678 MCLAIM(m, &tcp_tx_mowner); 679 MCLGET(m, M_DONTWAIT); 680 if ((m->m_flags & M_EXT) == 0) { 681 m_free(m); 682 m = NULL; 683 } 684 } 685 if (m == NULL) 686 return (ENOBUFS); 687 688 if (tcp_compat_42) 689 tlen = 1; 690 else 691 tlen = 0; 692 693 m->m_data += max_linkhdr; 694 bcopy(mtod(template, void *), mtod(m, void *), 695 template->m_len); 696 switch (family) { 697 case AF_INET: 698 ip = mtod(m, struct ip *); 699 th = (struct tcphdr *)(ip + 1); 700 break; 701 #ifdef INET6 702 case AF_INET6: 703 ip6 = mtod(m, struct ip6_hdr *); 704 th = (struct tcphdr *)(ip6 + 1); 705 break; 706 #endif 707 #if 0 708 default: 709 /* noone will visit here */ 710 m_freem(m); 711 return EAFNOSUPPORT; 712 #endif 713 } 714 flags = TH_ACK; 715 } else { 716 717 if ((m->m_flags & M_PKTHDR) == 0) { 718 #if 0 719 printf("non PKTHDR to tcp_respond\n"); 720 #endif 721 m_freem(m); 722 return EINVAL; 723 } 724 #ifdef DIAGNOSTIC 725 if (!th0) 726 panic("th0 == NULL in tcp_respond"); 727 #endif 728 729 /* get family information from m */ 730 switch (mtod(m, struct ip *)->ip_v) { 731 case 4: 732 family = AF_INET; 733 hlen = sizeof(struct ip); 734 ip = mtod(m, struct ip *); 735 break; 736 #ifdef INET6 737 case 6: 738 family = AF_INET6; 739 hlen = sizeof(struct ip6_hdr); 740 ip6 = mtod(m, struct ip6_hdr *); 741 break; 742 #endif 743 default: 744 m_freem(m); 745 return EAFNOSUPPORT; 746 } 747 /* clear h/w csum flags inherited from rx packet */ 748 m->m_pkthdr.csum_flags = 0; 749 750 if ((flags & TH_SYN) == 0 || sizeof(*th0) > (th0->th_off << 2)) 751 tlen = sizeof(*th0); 752 else 753 tlen = th0->th_off << 2; 754 755 if (m->m_len > hlen + tlen && (m->m_flags & M_EXT) == 0 && 756 mtod(m, char *) + hlen == (char *)th0) { 757 m->m_len = hlen + tlen; 758 m_freem(m->m_next); 759 m->m_next = NULL; 760 } else { 761 struct mbuf *n; 762 763 #ifdef DIAGNOSTIC 764 if (max_linkhdr + hlen + tlen > MCLBYTES) { 765 m_freem(m); 766 return EMSGSIZE; 767 } 768 #endif 769 MGETHDR(n, M_DONTWAIT, MT_HEADER); 770 if (n && max_linkhdr + hlen + tlen > MHLEN) { 771 MCLGET(n, M_DONTWAIT); 772 if ((n->m_flags & M_EXT) == 0) { 773 m_freem(n); 774 n = NULL; 775 } 776 } 777 if (!n) { 778 m_freem(m); 779 return ENOBUFS; 780 } 781 782 MCLAIM(n, &tcp_tx_mowner); 783 n->m_data += max_linkhdr; 784 n->m_len = hlen + tlen; 785 m_copyback(n, 0, hlen, mtod(m, void *)); 786 m_copyback(n, hlen, tlen, (void *)th0); 787 788 m_freem(m); 789 m = n; 790 n = NULL; 791 } 792 793 #define xchg(a,b,type) { type t; t=a; a=b; b=t; } 794 switch (family) { 795 case AF_INET: 796 ip = mtod(m, struct ip *); 797 th = (struct tcphdr *)(ip + 1); 798 ip->ip_p = IPPROTO_TCP; 799 xchg(ip->ip_dst, ip->ip_src, struct in_addr); 800 ip->ip_p = IPPROTO_TCP; 801 break; 802 #ifdef INET6 803 case AF_INET6: 804 ip6 = mtod(m, struct ip6_hdr *); 805 th = (struct tcphdr *)(ip6 + 1); 806 ip6->ip6_nxt = IPPROTO_TCP; 807 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); 808 ip6->ip6_nxt = IPPROTO_TCP; 809 break; 810 #endif 811 #if 0 812 default: 813 /* noone will visit here */ 814 m_freem(m); 815 return EAFNOSUPPORT; 816 #endif 817 } 818 xchg(th->th_dport, th->th_sport, u_int16_t); 819 #undef xchg 820 tlen = 0; /*be friendly with the following code*/ 821 } 822 th->th_seq = htonl(seq); 823 th->th_ack = htonl(ack); 824 th->th_x2 = 0; 825 if ((flags & TH_SYN) == 0) { 826 if (tp) 827 win >>= tp->rcv_scale; 828 if (win > TCP_MAXWIN) 829 win = TCP_MAXWIN; 830 th->th_win = htons((u_int16_t)win); 831 th->th_off = sizeof (struct tcphdr) >> 2; 832 tlen += sizeof(*th); 833 } else 834 tlen += th->th_off << 2; 835 m->m_len = hlen + tlen; 836 m->m_pkthdr.len = hlen + tlen; 837 m->m_pkthdr.rcvif = (struct ifnet *) 0; 838 th->th_flags = flags; 839 th->th_urp = 0; 840 841 switch (family) { 842 #ifdef INET 843 case AF_INET: 844 { 845 struct ipovly *ipov = (struct ipovly *)ip; 846 memset(ipov->ih_x1, 0, sizeof ipov->ih_x1); 847 ipov->ih_len = htons((u_int16_t)tlen); 848 849 th->th_sum = 0; 850 th->th_sum = in_cksum(m, hlen + tlen); 851 ip->ip_len = htons(hlen + tlen); 852 ip->ip_ttl = ip_defttl; 853 break; 854 } 855 #endif 856 #ifdef INET6 857 case AF_INET6: 858 { 859 th->th_sum = 0; 860 th->th_sum = in6_cksum(m, IPPROTO_TCP, sizeof(struct ip6_hdr), 861 tlen); 862 ip6->ip6_plen = htons(tlen); 863 if (tp && tp->t_in6pcb) { 864 struct ifnet *oifp; 865 ro = &tp->t_in6pcb->in6p_route; 866 oifp = (rt = rtcache_validate(ro)) != NULL ? rt->rt_ifp 867 : NULL; 868 ip6->ip6_hlim = in6_selecthlim(tp->t_in6pcb, oifp); 869 } else 870 ip6->ip6_hlim = ip6_defhlim; 871 ip6->ip6_flow &= ~IPV6_FLOWINFO_MASK; 872 if (ip6_auto_flowlabel) { 873 ip6->ip6_flow |= 874 (htonl(ip6_randomflowlabel()) & IPV6_FLOWLABEL_MASK); 875 } 876 break; 877 } 878 #endif 879 } 880 881 if (tp && tp->t_inpcb) 882 so = tp->t_inpcb->inp_socket; 883 #ifdef INET6 884 else if (tp && tp->t_in6pcb) 885 so = tp->t_in6pcb->in6p_socket; 886 #endif 887 else 888 so = NULL; 889 890 if (tp != NULL && tp->t_inpcb != NULL) { 891 ro = &tp->t_inpcb->inp_route; 892 #ifdef DIAGNOSTIC 893 if (family != AF_INET) 894 panic("tcp_respond: address family mismatch"); 895 if (!in_hosteq(ip->ip_dst, tp->t_inpcb->inp_faddr)) { 896 panic("tcp_respond: ip_dst %x != inp_faddr %x", 897 ntohl(ip->ip_dst.s_addr), 898 ntohl(tp->t_inpcb->inp_faddr.s_addr)); 899 } 900 #endif 901 } 902 #ifdef INET6 903 else if (tp != NULL && tp->t_in6pcb != NULL) { 904 ro = (struct route *)&tp->t_in6pcb->in6p_route; 905 #ifdef DIAGNOSTIC 906 if (family == AF_INET) { 907 if (!IN6_IS_ADDR_V4MAPPED(&tp->t_in6pcb->in6p_faddr)) 908 panic("tcp_respond: not mapped addr"); 909 if (memcmp(&ip->ip_dst, 910 &tp->t_in6pcb->in6p_faddr.s6_addr32[3], 911 sizeof(ip->ip_dst)) != 0) { 912 panic("tcp_respond: ip_dst != in6p_faddr"); 913 } 914 } else if (family == AF_INET6) { 915 if (!IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, 916 &tp->t_in6pcb->in6p_faddr)) 917 panic("tcp_respond: ip6_dst != in6p_faddr"); 918 } else 919 panic("tcp_respond: address family mismatch"); 920 #endif 921 } 922 #endif 923 else 924 ro = NULL; 925 926 switch (family) { 927 #ifdef INET 928 case AF_INET: 929 error = ip_output(m, NULL, ro, 930 (tp && tp->t_mtudisc ? IP_MTUDISC : 0), 931 (struct ip_moptions *)0, so); 932 break; 933 #endif 934 #ifdef INET6 935 case AF_INET6: 936 error = ip6_output(m, NULL, ro, 0, NULL, so, NULL); 937 break; 938 #endif 939 default: 940 error = EAFNOSUPPORT; 941 break; 942 } 943 944 return (error); 945 } 946 947 /* 948 * Template TCPCB. Rather than zeroing a new TCPCB and initializing 949 * a bunch of members individually, we maintain this template for the 950 * static and mostly-static components of the TCPCB, and copy it into 951 * the new TCPCB instead. 952 */ 953 static struct tcpcb tcpcb_template = { 954 .t_srtt = TCPTV_SRTTBASE, 955 .t_rttmin = TCPTV_MIN, 956 957 .snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT, 958 .snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT, 959 .snd_numholes = 0, 960 961 .t_partialacks = -1, 962 .t_bytes_acked = 0, 963 }; 964 965 /* 966 * Updates the TCPCB template whenever a parameter that would affect 967 * the template is changed. 968 */ 969 void 970 tcp_tcpcb_template(void) 971 { 972 struct tcpcb *tp = &tcpcb_template; 973 int flags; 974 975 tp->t_peermss = tcp_mssdflt; 976 tp->t_ourmss = tcp_mssdflt; 977 tp->t_segsz = tcp_mssdflt; 978 979 flags = 0; 980 if (tcp_do_rfc1323 && tcp_do_win_scale) 981 flags |= TF_REQ_SCALE; 982 if (tcp_do_rfc1323 && tcp_do_timestamps) 983 flags |= TF_REQ_TSTMP; 984 tp->t_flags = flags; 985 986 /* 987 * Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no 988 * rtt estimate. Set rttvar so that srtt + 2 * rttvar gives 989 * reasonable initial retransmit time. 990 */ 991 tp->t_rttvar = tcp_rttdflt * PR_SLOWHZ << (TCP_RTTVAR_SHIFT + 2 - 1); 992 TCPT_RANGESET(tp->t_rxtcur, TCP_REXMTVAL(tp), 993 TCPTV_MIN, TCPTV_REXMTMAX); 994 995 /* Keep Alive */ 996 tp->t_keepinit = tcp_keepinit; 997 tp->t_keepidle = tcp_keepidle; 998 tp->t_keepintvl = tcp_keepintvl; 999 tp->t_keepcnt = tcp_keepcnt; 1000 tp->t_maxidle = tp->t_keepcnt * tp->t_keepintvl; 1001 1002 /* MSL */ 1003 tp->t_msl = TCPTV_MSL; 1004 } 1005 1006 /* 1007 * Create a new TCP control block, making an 1008 * empty reassembly queue and hooking it to the argument 1009 * protocol control block. 1010 */ 1011 /* family selects inpcb, or in6pcb */ 1012 struct tcpcb * 1013 tcp_newtcpcb(int family, void *aux) 1014 { 1015 #ifdef INET6 1016 struct rtentry *rt; 1017 #endif 1018 struct tcpcb *tp; 1019 int i; 1020 1021 /* XXX Consider using a pool_cache for speed. */ 1022 tp = pool_get(&tcpcb_pool, PR_NOWAIT); /* splsoftnet via tcp_usrreq */ 1023 if (tp == NULL) 1024 return (NULL); 1025 memcpy(tp, &tcpcb_template, sizeof(*tp)); 1026 TAILQ_INIT(&tp->segq); 1027 TAILQ_INIT(&tp->timeq); 1028 tp->t_family = family; /* may be overridden later on */ 1029 TAILQ_INIT(&tp->snd_holes); 1030 LIST_INIT(&tp->t_sc); /* XXX can template this */ 1031 1032 /* Don't sweat this loop; hopefully the compiler will unroll it. */ 1033 for (i = 0; i < TCPT_NTIMERS; i++) { 1034 callout_init(&tp->t_timer[i], CALLOUT_MPSAFE); 1035 TCP_TIMER_INIT(tp, i); 1036 } 1037 callout_init(&tp->t_delack_ch, CALLOUT_MPSAFE); 1038 1039 switch (family) { 1040 case AF_INET: 1041 { 1042 struct inpcb *inp = (struct inpcb *)aux; 1043 1044 inp->inp_ip.ip_ttl = ip_defttl; 1045 inp->inp_ppcb = (void *)tp; 1046 1047 tp->t_inpcb = inp; 1048 tp->t_mtudisc = ip_mtudisc; 1049 break; 1050 } 1051 #ifdef INET6 1052 case AF_INET6: 1053 { 1054 struct in6pcb *in6p = (struct in6pcb *)aux; 1055 1056 in6p->in6p_ip6.ip6_hlim = in6_selecthlim(in6p, 1057 (rt = rtcache_validate(&in6p->in6p_route)) != NULL 1058 ? rt->rt_ifp 1059 : NULL); 1060 in6p->in6p_ppcb = (void *)tp; 1061 1062 tp->t_in6pcb = in6p; 1063 /* for IPv6, always try to run path MTU discovery */ 1064 tp->t_mtudisc = 1; 1065 break; 1066 } 1067 #endif /* INET6 */ 1068 default: 1069 for (i = 0; i < TCPT_NTIMERS; i++) 1070 callout_destroy(&tp->t_timer[i]); 1071 callout_destroy(&tp->t_delack_ch); 1072 pool_put(&tcpcb_pool, tp); /* splsoftnet via tcp_usrreq */ 1073 return (NULL); 1074 } 1075 1076 /* 1077 * Initialize our timebase. When we send timestamps, we take 1078 * the delta from tcp_now -- this means each connection always 1079 * gets a timebase of 1, which makes it, among other things, 1080 * more difficult to determine how long a system has been up, 1081 * and thus how many TCP sequence increments have occurred. 1082 * 1083 * We start with 1, because 0 doesn't work with linux, which 1084 * considers timestamp 0 in a SYN packet as a bug and disables 1085 * timestamps. 1086 */ 1087 tp->ts_timebase = tcp_now - 1; 1088 1089 tcp_congctl_select(tp, tcp_congctl_global_name); 1090 1091 return (tp); 1092 } 1093 1094 /* 1095 * Drop a TCP connection, reporting 1096 * the specified error. If connection is synchronized, 1097 * then send a RST to peer. 1098 */ 1099 struct tcpcb * 1100 tcp_drop(struct tcpcb *tp, int errno) 1101 { 1102 struct socket *so = NULL; 1103 1104 #ifdef DIAGNOSTIC 1105 if (tp->t_inpcb && tp->t_in6pcb) 1106 panic("tcp_drop: both t_inpcb and t_in6pcb are set"); 1107 #endif 1108 #ifdef INET 1109 if (tp->t_inpcb) 1110 so = tp->t_inpcb->inp_socket; 1111 #endif 1112 #ifdef INET6 1113 if (tp->t_in6pcb) 1114 so = tp->t_in6pcb->in6p_socket; 1115 #endif 1116 if (!so) 1117 return NULL; 1118 1119 if (TCPS_HAVERCVDSYN(tp->t_state)) { 1120 tp->t_state = TCPS_CLOSED; 1121 (void) tcp_output(tp); 1122 TCP_STATINC(TCP_STAT_DROPS); 1123 } else 1124 TCP_STATINC(TCP_STAT_CONNDROPS); 1125 if (errno == ETIMEDOUT && tp->t_softerror) 1126 errno = tp->t_softerror; 1127 so->so_error = errno; 1128 return (tcp_close(tp)); 1129 } 1130 1131 /* 1132 * Close a TCP control block: 1133 * discard all space held by the tcp 1134 * discard internet protocol block 1135 * wake up any sleepers 1136 */ 1137 struct tcpcb * 1138 tcp_close(struct tcpcb *tp) 1139 { 1140 struct inpcb *inp; 1141 #ifdef INET6 1142 struct in6pcb *in6p; 1143 #endif 1144 struct socket *so; 1145 #ifdef RTV_RTT 1146 struct rtentry *rt; 1147 #endif 1148 struct route *ro; 1149 int j; 1150 1151 inp = tp->t_inpcb; 1152 #ifdef INET6 1153 in6p = tp->t_in6pcb; 1154 #endif 1155 so = NULL; 1156 ro = NULL; 1157 if (inp) { 1158 so = inp->inp_socket; 1159 ro = &inp->inp_route; 1160 } 1161 #ifdef INET6 1162 else if (in6p) { 1163 so = in6p->in6p_socket; 1164 ro = (struct route *)&in6p->in6p_route; 1165 } 1166 #endif 1167 1168 #ifdef RTV_RTT 1169 /* 1170 * If we sent enough data to get some meaningful characteristics, 1171 * save them in the routing entry. 'Enough' is arbitrarily 1172 * defined as the sendpipesize (default 4K) * 16. This would 1173 * give us 16 rtt samples assuming we only get one sample per 1174 * window (the usual case on a long haul net). 16 samples is 1175 * enough for the srtt filter to converge to within 5% of the correct 1176 * value; fewer samples and we could save a very bogus rtt. 1177 * 1178 * Don't update the default route's characteristics and don't 1179 * update anything that the user "locked". 1180 */ 1181 if (SEQ_LT(tp->iss + so->so_snd.sb_hiwat * 16, tp->snd_max) && 1182 ro && (rt = rtcache_validate(ro)) != NULL && 1183 !in_nullhost(satocsin(rt_getkey(rt))->sin_addr)) { 1184 u_long i = 0; 1185 1186 if ((rt->rt_rmx.rmx_locks & RTV_RTT) == 0) { 1187 i = tp->t_srtt * 1188 ((RTM_RTTUNIT / PR_SLOWHZ) >> (TCP_RTT_SHIFT + 2)); 1189 if (rt->rt_rmx.rmx_rtt && i) 1190 /* 1191 * filter this update to half the old & half 1192 * the new values, converting scale. 1193 * See route.h and tcp_var.h for a 1194 * description of the scaling constants. 1195 */ 1196 rt->rt_rmx.rmx_rtt = 1197 (rt->rt_rmx.rmx_rtt + i) / 2; 1198 else 1199 rt->rt_rmx.rmx_rtt = i; 1200 } 1201 if ((rt->rt_rmx.rmx_locks & RTV_RTTVAR) == 0) { 1202 i = tp->t_rttvar * 1203 ((RTM_RTTUNIT / PR_SLOWHZ) >> (TCP_RTTVAR_SHIFT + 2)); 1204 if (rt->rt_rmx.rmx_rttvar && i) 1205 rt->rt_rmx.rmx_rttvar = 1206 (rt->rt_rmx.rmx_rttvar + i) / 2; 1207 else 1208 rt->rt_rmx.rmx_rttvar = i; 1209 } 1210 /* 1211 * update the pipelimit (ssthresh) if it has been updated 1212 * already or if a pipesize was specified & the threshhold 1213 * got below half the pipesize. I.e., wait for bad news 1214 * before we start updating, then update on both good 1215 * and bad news. 1216 */ 1217 if (((rt->rt_rmx.rmx_locks & RTV_SSTHRESH) == 0 && 1218 (i = tp->snd_ssthresh) && rt->rt_rmx.rmx_ssthresh) || 1219 i < (rt->rt_rmx.rmx_sendpipe / 2)) { 1220 /* 1221 * convert the limit from user data bytes to 1222 * packets then to packet data bytes. 1223 */ 1224 i = (i + tp->t_segsz / 2) / tp->t_segsz; 1225 if (i < 2) 1226 i = 2; 1227 i *= (u_long)(tp->t_segsz + sizeof (struct tcpiphdr)); 1228 if (rt->rt_rmx.rmx_ssthresh) 1229 rt->rt_rmx.rmx_ssthresh = 1230 (rt->rt_rmx.rmx_ssthresh + i) / 2; 1231 else 1232 rt->rt_rmx.rmx_ssthresh = i; 1233 } 1234 } 1235 #endif /* RTV_RTT */ 1236 /* free the reassembly queue, if any */ 1237 TCP_REASS_LOCK(tp); 1238 (void) tcp_freeq(tp); 1239 TCP_REASS_UNLOCK(tp); 1240 1241 /* free the SACK holes list. */ 1242 tcp_free_sackholes(tp); 1243 tcp_congctl_release(tp); 1244 syn_cache_cleanup(tp); 1245 1246 if (tp->t_template) { 1247 m_free(tp->t_template); 1248 tp->t_template = NULL; 1249 } 1250 1251 /* 1252 * Detaching the pcb will unlock the socket/tcpcb, and stopping 1253 * the timers can also drop the lock. We need to prevent access 1254 * to the tcpcb as it's half torn down. Flag the pcb as dead 1255 * (prevents access by timers) and only then detach it. 1256 */ 1257 tp->t_flags |= TF_DEAD; 1258 if (inp) { 1259 inp->inp_ppcb = 0; 1260 soisdisconnected(so); 1261 in_pcbdetach(inp); 1262 } 1263 #ifdef INET6 1264 else if (in6p) { 1265 in6p->in6p_ppcb = 0; 1266 soisdisconnected(so); 1267 in6_pcbdetach(in6p); 1268 } 1269 #endif 1270 /* 1271 * pcb is no longer visble elsewhere, so we can safely release 1272 * the lock in callout_halt() if needed. 1273 */ 1274 TCP_STATINC(TCP_STAT_CLOSED); 1275 for (j = 0; j < TCPT_NTIMERS; j++) { 1276 callout_halt(&tp->t_timer[j], softnet_lock); 1277 callout_destroy(&tp->t_timer[j]); 1278 } 1279 callout_halt(&tp->t_delack_ch, softnet_lock); 1280 callout_destroy(&tp->t_delack_ch); 1281 pool_put(&tcpcb_pool, tp); 1282 1283 return ((struct tcpcb *)0); 1284 } 1285 1286 int 1287 tcp_freeq(struct tcpcb *tp) 1288 { 1289 struct ipqent *qe; 1290 int rv = 0; 1291 #ifdef TCPREASS_DEBUG 1292 int i = 0; 1293 #endif 1294 1295 TCP_REASS_LOCK_CHECK(tp); 1296 1297 while ((qe = TAILQ_FIRST(&tp->segq)) != NULL) { 1298 #ifdef TCPREASS_DEBUG 1299 printf("tcp_freeq[%p,%d]: %u:%u(%u) 0x%02x\n", 1300 tp, i++, qe->ipqe_seq, qe->ipqe_seq + qe->ipqe_len, 1301 qe->ipqe_len, qe->ipqe_flags & (TH_SYN|TH_FIN|TH_RST)); 1302 #endif 1303 TAILQ_REMOVE(&tp->segq, qe, ipqe_q); 1304 TAILQ_REMOVE(&tp->timeq, qe, ipqe_timeq); 1305 m_freem(qe->ipqe_m); 1306 tcpipqent_free(qe); 1307 rv = 1; 1308 } 1309 tp->t_segqlen = 0; 1310 KASSERT(TAILQ_EMPTY(&tp->timeq)); 1311 return (rv); 1312 } 1313 1314 void 1315 tcp_fasttimo(void) 1316 { 1317 if (tcp_drainwanted) { 1318 tcp_drain(); 1319 tcp_drainwanted = 0; 1320 } 1321 } 1322 1323 void 1324 tcp_drainstub(void) 1325 { 1326 tcp_drainwanted = 1; 1327 } 1328 1329 /* 1330 * Protocol drain routine. Called when memory is in short supply. 1331 * Called from pr_fasttimo thus a callout context. 1332 */ 1333 void 1334 tcp_drain(void) 1335 { 1336 struct inpcb_hdr *inph; 1337 struct tcpcb *tp; 1338 1339 mutex_enter(softnet_lock); 1340 KERNEL_LOCK(1, NULL); 1341 1342 /* 1343 * Free the sequence queue of all TCP connections. 1344 */ 1345 CIRCLEQ_FOREACH(inph, &tcbtable.inpt_queue, inph_queue) { 1346 switch (inph->inph_af) { 1347 case AF_INET: 1348 tp = intotcpcb((struct inpcb *)inph); 1349 break; 1350 #ifdef INET6 1351 case AF_INET6: 1352 tp = in6totcpcb((struct in6pcb *)inph); 1353 break; 1354 #endif 1355 default: 1356 tp = NULL; 1357 break; 1358 } 1359 if (tp != NULL) { 1360 /* 1361 * We may be called from a device's interrupt 1362 * context. If the tcpcb is already busy, 1363 * just bail out now. 1364 */ 1365 if (tcp_reass_lock_try(tp) == 0) 1366 continue; 1367 if (tcp_freeq(tp)) 1368 TCP_STATINC(TCP_STAT_CONNSDRAINED); 1369 TCP_REASS_UNLOCK(tp); 1370 } 1371 } 1372 1373 KERNEL_UNLOCK_ONE(NULL); 1374 mutex_exit(softnet_lock); 1375 } 1376 1377 /* 1378 * Notify a tcp user of an asynchronous error; 1379 * store error as soft error, but wake up user 1380 * (for now, won't do anything until can select for soft error). 1381 */ 1382 void 1383 tcp_notify(struct inpcb *inp, int error) 1384 { 1385 struct tcpcb *tp = (struct tcpcb *)inp->inp_ppcb; 1386 struct socket *so = inp->inp_socket; 1387 1388 /* 1389 * Ignore some errors if we are hooked up. 1390 * If connection hasn't completed, has retransmitted several times, 1391 * and receives a second error, give up now. This is better 1392 * than waiting a long time to establish a connection that 1393 * can never complete. 1394 */ 1395 if (tp->t_state == TCPS_ESTABLISHED && 1396 (error == EHOSTUNREACH || error == ENETUNREACH || 1397 error == EHOSTDOWN)) { 1398 return; 1399 } else if (TCPS_HAVEESTABLISHED(tp->t_state) == 0 && 1400 tp->t_rxtshift > 3 && tp->t_softerror) 1401 so->so_error = error; 1402 else 1403 tp->t_softerror = error; 1404 cv_broadcast(&so->so_cv); 1405 sorwakeup(so); 1406 sowwakeup(so); 1407 } 1408 1409 #ifdef INET6 1410 void 1411 tcp6_notify(struct in6pcb *in6p, int error) 1412 { 1413 struct tcpcb *tp = (struct tcpcb *)in6p->in6p_ppcb; 1414 struct socket *so = in6p->in6p_socket; 1415 1416 /* 1417 * Ignore some errors if we are hooked up. 1418 * If connection hasn't completed, has retransmitted several times, 1419 * and receives a second error, give up now. This is better 1420 * than waiting a long time to establish a connection that 1421 * can never complete. 1422 */ 1423 if (tp->t_state == TCPS_ESTABLISHED && 1424 (error == EHOSTUNREACH || error == ENETUNREACH || 1425 error == EHOSTDOWN)) { 1426 return; 1427 } else if (TCPS_HAVEESTABLISHED(tp->t_state) == 0 && 1428 tp->t_rxtshift > 3 && tp->t_softerror) 1429 so->so_error = error; 1430 else 1431 tp->t_softerror = error; 1432 cv_broadcast(&so->so_cv); 1433 sorwakeup(so); 1434 sowwakeup(so); 1435 } 1436 #endif 1437 1438 #ifdef INET6 1439 void * 1440 tcp6_ctlinput(int cmd, const struct sockaddr *sa, void *d) 1441 { 1442 struct tcphdr th; 1443 void (*notify)(struct in6pcb *, int) = tcp6_notify; 1444 int nmatch; 1445 struct ip6_hdr *ip6; 1446 const struct sockaddr_in6 *sa6_src = NULL; 1447 const struct sockaddr_in6 *sa6 = (const struct sockaddr_in6 *)sa; 1448 struct mbuf *m; 1449 int off; 1450 1451 if (sa->sa_family != AF_INET6 || 1452 sa->sa_len != sizeof(struct sockaddr_in6)) 1453 return NULL; 1454 if ((unsigned)cmd >= PRC_NCMDS) 1455 return NULL; 1456 else if (cmd == PRC_QUENCH) { 1457 /* 1458 * Don't honor ICMP Source Quench messages meant for 1459 * TCP connections. 1460 */ 1461 return NULL; 1462 } else if (PRC_IS_REDIRECT(cmd)) 1463 notify = in6_rtchange, d = NULL; 1464 else if (cmd == PRC_MSGSIZE) 1465 ; /* special code is present, see below */ 1466 else if (cmd == PRC_HOSTDEAD) 1467 d = NULL; 1468 else if (inet6ctlerrmap[cmd] == 0) 1469 return NULL; 1470 1471 /* if the parameter is from icmp6, decode it. */ 1472 if (d != NULL) { 1473 struct ip6ctlparam *ip6cp = (struct ip6ctlparam *)d; 1474 m = ip6cp->ip6c_m; 1475 ip6 = ip6cp->ip6c_ip6; 1476 off = ip6cp->ip6c_off; 1477 sa6_src = ip6cp->ip6c_src; 1478 } else { 1479 m = NULL; 1480 ip6 = NULL; 1481 sa6_src = &sa6_any; 1482 off = 0; 1483 } 1484 1485 if (ip6) { 1486 /* 1487 * XXX: We assume that when ip6 is non NULL, 1488 * M and OFF are valid. 1489 */ 1490 1491 /* check if we can safely examine src and dst ports */ 1492 if (m->m_pkthdr.len < off + sizeof(th)) { 1493 if (cmd == PRC_MSGSIZE) 1494 icmp6_mtudisc_update((struct ip6ctlparam *)d, 0); 1495 return NULL; 1496 } 1497 1498 memset(&th, 0, sizeof(th)); 1499 m_copydata(m, off, sizeof(th), (void *)&th); 1500 1501 if (cmd == PRC_MSGSIZE) { 1502 int valid = 0; 1503 1504 /* 1505 * Check to see if we have a valid TCP connection 1506 * corresponding to the address in the ICMPv6 message 1507 * payload. 1508 */ 1509 if (in6_pcblookup_connect(&tcbtable, &sa6->sin6_addr, 1510 th.th_dport, 1511 (const struct in6_addr *)&sa6_src->sin6_addr, 1512 th.th_sport, 0, 0)) 1513 valid++; 1514 1515 /* 1516 * Depending on the value of "valid" and routing table 1517 * size (mtudisc_{hi,lo}wat), we will: 1518 * - recalcurate the new MTU and create the 1519 * corresponding routing entry, or 1520 * - ignore the MTU change notification. 1521 */ 1522 icmp6_mtudisc_update((struct ip6ctlparam *)d, valid); 1523 1524 /* 1525 * no need to call in6_pcbnotify, it should have been 1526 * called via callback if necessary 1527 */ 1528 return NULL; 1529 } 1530 1531 nmatch = in6_pcbnotify(&tcbtable, sa, th.th_dport, 1532 (const struct sockaddr *)sa6_src, th.th_sport, cmd, NULL, notify); 1533 if (nmatch == 0 && syn_cache_count && 1534 (inet6ctlerrmap[cmd] == EHOSTUNREACH || 1535 inet6ctlerrmap[cmd] == ENETUNREACH || 1536 inet6ctlerrmap[cmd] == EHOSTDOWN)) 1537 syn_cache_unreach((const struct sockaddr *)sa6_src, 1538 sa, &th); 1539 } else { 1540 (void) in6_pcbnotify(&tcbtable, sa, 0, 1541 (const struct sockaddr *)sa6_src, 0, cmd, NULL, notify); 1542 } 1543 1544 return NULL; 1545 } 1546 #endif 1547 1548 #ifdef INET 1549 /* assumes that ip header and tcp header are contiguous on mbuf */ 1550 void * 1551 tcp_ctlinput(int cmd, const struct sockaddr *sa, void *v) 1552 { 1553 struct ip *ip = v; 1554 struct tcphdr *th; 1555 struct icmp *icp; 1556 extern const int inetctlerrmap[]; 1557 void (*notify)(struct inpcb *, int) = tcp_notify; 1558 int errno; 1559 int nmatch; 1560 struct tcpcb *tp; 1561 u_int mtu; 1562 tcp_seq seq; 1563 struct inpcb *inp; 1564 #ifdef INET6 1565 struct in6pcb *in6p; 1566 struct in6_addr src6, dst6; 1567 #endif 1568 1569 if (sa->sa_family != AF_INET || 1570 sa->sa_len != sizeof(struct sockaddr_in)) 1571 return NULL; 1572 if ((unsigned)cmd >= PRC_NCMDS) 1573 return NULL; 1574 errno = inetctlerrmap[cmd]; 1575 if (cmd == PRC_QUENCH) 1576 /* 1577 * Don't honor ICMP Source Quench messages meant for 1578 * TCP connections. 1579 */ 1580 return NULL; 1581 else if (PRC_IS_REDIRECT(cmd)) 1582 notify = in_rtchange, ip = 0; 1583 else if (cmd == PRC_MSGSIZE && ip && ip->ip_v == 4) { 1584 /* 1585 * Check to see if we have a valid TCP connection 1586 * corresponding to the address in the ICMP message 1587 * payload. 1588 * 1589 * Boundary check is made in icmp_input(), with ICMP_ADVLENMIN. 1590 */ 1591 th = (struct tcphdr *)((char *)ip + (ip->ip_hl << 2)); 1592 #ifdef INET6 1593 memset(&src6, 0, sizeof(src6)); 1594 memset(&dst6, 0, sizeof(dst6)); 1595 src6.s6_addr16[5] = dst6.s6_addr16[5] = 0xffff; 1596 memcpy(&src6.s6_addr32[3], &ip->ip_src, sizeof(struct in_addr)); 1597 memcpy(&dst6.s6_addr32[3], &ip->ip_dst, sizeof(struct in_addr)); 1598 #endif 1599 if ((inp = in_pcblookup_connect(&tcbtable, ip->ip_dst, 1600 th->th_dport, ip->ip_src, th->th_sport, 0)) != NULL) 1601 #ifdef INET6 1602 in6p = NULL; 1603 #else 1604 ; 1605 #endif 1606 #ifdef INET6 1607 else if ((in6p = in6_pcblookup_connect(&tcbtable, &dst6, 1608 th->th_dport, &src6, th->th_sport, 0, 0)) != NULL) 1609 ; 1610 #endif 1611 else 1612 return NULL; 1613 1614 /* 1615 * Now that we've validated that we are actually communicating 1616 * with the host indicated in the ICMP message, locate the 1617 * ICMP header, recalculate the new MTU, and create the 1618 * corresponding routing entry. 1619 */ 1620 icp = (struct icmp *)((char *)ip - 1621 offsetof(struct icmp, icmp_ip)); 1622 if (inp) { 1623 if ((tp = intotcpcb(inp)) == NULL) 1624 return NULL; 1625 } 1626 #ifdef INET6 1627 else if (in6p) { 1628 if ((tp = in6totcpcb(in6p)) == NULL) 1629 return NULL; 1630 } 1631 #endif 1632 else 1633 return NULL; 1634 seq = ntohl(th->th_seq); 1635 if (SEQ_LT(seq, tp->snd_una) || SEQ_GT(seq, tp->snd_max)) 1636 return NULL; 1637 /* 1638 * If the ICMP message advertises a Next-Hop MTU 1639 * equal or larger than the maximum packet size we have 1640 * ever sent, drop the message. 1641 */ 1642 mtu = (u_int)ntohs(icp->icmp_nextmtu); 1643 if (mtu >= tp->t_pmtud_mtu_sent) 1644 return NULL; 1645 if (mtu >= tcp_hdrsz(tp) + tp->t_pmtud_mss_acked) { 1646 /* 1647 * Calculate new MTU, and create corresponding 1648 * route (traditional PMTUD). 1649 */ 1650 tp->t_flags &= ~TF_PMTUD_PEND; 1651 icmp_mtudisc(icp, ip->ip_dst); 1652 } else { 1653 /* 1654 * Record the information got in the ICMP 1655 * message; act on it later. 1656 * If we had already recorded an ICMP message, 1657 * replace the old one only if the new message 1658 * refers to an older TCP segment 1659 */ 1660 if (tp->t_flags & TF_PMTUD_PEND) { 1661 if (SEQ_LT(tp->t_pmtud_th_seq, seq)) 1662 return NULL; 1663 } else 1664 tp->t_flags |= TF_PMTUD_PEND; 1665 tp->t_pmtud_th_seq = seq; 1666 tp->t_pmtud_nextmtu = icp->icmp_nextmtu; 1667 tp->t_pmtud_ip_len = icp->icmp_ip.ip_len; 1668 tp->t_pmtud_ip_hl = icp->icmp_ip.ip_hl; 1669 } 1670 return NULL; 1671 } else if (cmd == PRC_HOSTDEAD) 1672 ip = 0; 1673 else if (errno == 0) 1674 return NULL; 1675 if (ip && ip->ip_v == 4 && sa->sa_family == AF_INET) { 1676 th = (struct tcphdr *)((char *)ip + (ip->ip_hl << 2)); 1677 nmatch = in_pcbnotify(&tcbtable, satocsin(sa)->sin_addr, 1678 th->th_dport, ip->ip_src, th->th_sport, errno, notify); 1679 if (nmatch == 0 && syn_cache_count && 1680 (inetctlerrmap[cmd] == EHOSTUNREACH || 1681 inetctlerrmap[cmd] == ENETUNREACH || 1682 inetctlerrmap[cmd] == EHOSTDOWN)) { 1683 struct sockaddr_in sin; 1684 memset(&sin, 0, sizeof(sin)); 1685 sin.sin_len = sizeof(sin); 1686 sin.sin_family = AF_INET; 1687 sin.sin_port = th->th_sport; 1688 sin.sin_addr = ip->ip_src; 1689 syn_cache_unreach((struct sockaddr *)&sin, sa, th); 1690 } 1691 1692 /* XXX mapped address case */ 1693 } else 1694 in_pcbnotifyall(&tcbtable, satocsin(sa)->sin_addr, errno, 1695 notify); 1696 return NULL; 1697 } 1698 1699 /* 1700 * When a source quench is received, we are being notified of congestion. 1701 * Close the congestion window down to the Loss Window (one segment). 1702 * We will gradually open it again as we proceed. 1703 */ 1704 void 1705 tcp_quench(struct inpcb *inp, int errno) 1706 { 1707 struct tcpcb *tp = intotcpcb(inp); 1708 1709 if (tp) { 1710 tp->snd_cwnd = tp->t_segsz; 1711 tp->t_bytes_acked = 0; 1712 } 1713 } 1714 #endif 1715 1716 #ifdef INET6 1717 void 1718 tcp6_quench(struct in6pcb *in6p, int errno) 1719 { 1720 struct tcpcb *tp = in6totcpcb(in6p); 1721 1722 if (tp) { 1723 tp->snd_cwnd = tp->t_segsz; 1724 tp->t_bytes_acked = 0; 1725 } 1726 } 1727 #endif 1728 1729 #ifdef INET 1730 /* 1731 * Path MTU Discovery handlers. 1732 */ 1733 void 1734 tcp_mtudisc_callback(struct in_addr faddr) 1735 { 1736 #ifdef INET6 1737 struct in6_addr in6; 1738 #endif 1739 1740 in_pcbnotifyall(&tcbtable, faddr, EMSGSIZE, tcp_mtudisc); 1741 #ifdef INET6 1742 memset(&in6, 0, sizeof(in6)); 1743 in6.s6_addr16[5] = 0xffff; 1744 memcpy(&in6.s6_addr32[3], &faddr, sizeof(struct in_addr)); 1745 tcp6_mtudisc_callback(&in6); 1746 #endif 1747 } 1748 1749 /* 1750 * On receipt of path MTU corrections, flush old route and replace it 1751 * with the new one. Retransmit all unacknowledged packets, to ensure 1752 * that all packets will be received. 1753 */ 1754 void 1755 tcp_mtudisc(struct inpcb *inp, int errno) 1756 { 1757 struct tcpcb *tp = intotcpcb(inp); 1758 struct rtentry *rt = in_pcbrtentry(inp); 1759 1760 if (tp != 0) { 1761 if (rt != 0) { 1762 /* 1763 * If this was not a host route, remove and realloc. 1764 */ 1765 if ((rt->rt_flags & RTF_HOST) == 0) { 1766 in_rtchange(inp, errno); 1767 if ((rt = in_pcbrtentry(inp)) == 0) 1768 return; 1769 } 1770 1771 /* 1772 * Slow start out of the error condition. We 1773 * use the MTU because we know it's smaller 1774 * than the previously transmitted segment. 1775 * 1776 * Note: This is more conservative than the 1777 * suggestion in draft-floyd-incr-init-win-03. 1778 */ 1779 if (rt->rt_rmx.rmx_mtu != 0) 1780 tp->snd_cwnd = 1781 TCP_INITIAL_WINDOW(tcp_init_win, 1782 rt->rt_rmx.rmx_mtu); 1783 } 1784 1785 /* 1786 * Resend unacknowledged packets. 1787 */ 1788 tp->snd_nxt = tp->sack_newdata = tp->snd_una; 1789 tcp_output(tp); 1790 } 1791 } 1792 #endif 1793 1794 #ifdef INET6 1795 /* 1796 * Path MTU Discovery handlers. 1797 */ 1798 void 1799 tcp6_mtudisc_callback(struct in6_addr *faddr) 1800 { 1801 struct sockaddr_in6 sin6; 1802 1803 memset(&sin6, 0, sizeof(sin6)); 1804 sin6.sin6_family = AF_INET6; 1805 sin6.sin6_len = sizeof(struct sockaddr_in6); 1806 sin6.sin6_addr = *faddr; 1807 (void) in6_pcbnotify(&tcbtable, (struct sockaddr *)&sin6, 0, 1808 (const struct sockaddr *)&sa6_any, 0, PRC_MSGSIZE, NULL, tcp6_mtudisc); 1809 } 1810 1811 void 1812 tcp6_mtudisc(struct in6pcb *in6p, int errno) 1813 { 1814 struct tcpcb *tp = in6totcpcb(in6p); 1815 struct rtentry *rt = in6_pcbrtentry(in6p); 1816 1817 if (tp != 0) { 1818 if (rt != 0) { 1819 /* 1820 * If this was not a host route, remove and realloc. 1821 */ 1822 if ((rt->rt_flags & RTF_HOST) == 0) { 1823 in6_rtchange(in6p, errno); 1824 if ((rt = in6_pcbrtentry(in6p)) == 0) 1825 return; 1826 } 1827 1828 /* 1829 * Slow start out of the error condition. We 1830 * use the MTU because we know it's smaller 1831 * than the previously transmitted segment. 1832 * 1833 * Note: This is more conservative than the 1834 * suggestion in draft-floyd-incr-init-win-03. 1835 */ 1836 if (rt->rt_rmx.rmx_mtu != 0) 1837 tp->snd_cwnd = 1838 TCP_INITIAL_WINDOW(tcp_init_win, 1839 rt->rt_rmx.rmx_mtu); 1840 } 1841 1842 /* 1843 * Resend unacknowledged packets. 1844 */ 1845 tp->snd_nxt = tp->sack_newdata = tp->snd_una; 1846 tcp_output(tp); 1847 } 1848 } 1849 #endif /* INET6 */ 1850 1851 /* 1852 * Compute the MSS to advertise to the peer. Called only during 1853 * the 3-way handshake. If we are the server (peer initiated 1854 * connection), we are called with a pointer to the interface 1855 * on which the SYN packet arrived. If we are the client (we 1856 * initiated connection), we are called with a pointer to the 1857 * interface out which this connection should go. 1858 * 1859 * NOTE: Do not subtract IP option/extension header size nor IPsec 1860 * header size from MSS advertisement. MSS option must hold the maximum 1861 * segment size we can accept, so it must always be: 1862 * max(if mtu) - ip header - tcp header 1863 */ 1864 u_long 1865 tcp_mss_to_advertise(const struct ifnet *ifp, int af) 1866 { 1867 extern u_long in_maxmtu; 1868 u_long mss = 0; 1869 u_long hdrsiz; 1870 1871 /* 1872 * In order to avoid defeating path MTU discovery on the peer, 1873 * we advertise the max MTU of all attached networks as our MSS, 1874 * per RFC 1191, section 3.1. 1875 * 1876 * We provide the option to advertise just the MTU of 1877 * the interface on which we hope this connection will 1878 * be receiving. If we are responding to a SYN, we 1879 * will have a pretty good idea about this, but when 1880 * initiating a connection there is a bit more doubt. 1881 * 1882 * We also need to ensure that loopback has a large enough 1883 * MSS, as the loopback MTU is never included in in_maxmtu. 1884 */ 1885 1886 if (ifp != NULL) 1887 switch (af) { 1888 case AF_INET: 1889 mss = ifp->if_mtu; 1890 break; 1891 #ifdef INET6 1892 case AF_INET6: 1893 mss = IN6_LINKMTU(ifp); 1894 break; 1895 #endif 1896 } 1897 1898 if (tcp_mss_ifmtu == 0) 1899 switch (af) { 1900 case AF_INET: 1901 mss = max(in_maxmtu, mss); 1902 break; 1903 #ifdef INET6 1904 case AF_INET6: 1905 mss = max(in6_maxmtu, mss); 1906 break; 1907 #endif 1908 } 1909 1910 switch (af) { 1911 case AF_INET: 1912 hdrsiz = sizeof(struct ip); 1913 break; 1914 #ifdef INET6 1915 case AF_INET6: 1916 hdrsiz = sizeof(struct ip6_hdr); 1917 break; 1918 #endif 1919 default: 1920 hdrsiz = 0; 1921 break; 1922 } 1923 hdrsiz += sizeof(struct tcphdr); 1924 if (mss > hdrsiz) 1925 mss -= hdrsiz; 1926 1927 mss = max(tcp_mssdflt, mss); 1928 return (mss); 1929 } 1930 1931 /* 1932 * Set connection variables based on the peer's advertised MSS. 1933 * We are passed the TCPCB for the actual connection. If we 1934 * are the server, we are called by the compressed state engine 1935 * when the 3-way handshake is complete. If we are the client, 1936 * we are called when we receive the SYN,ACK from the server. 1937 * 1938 * NOTE: Our advertised MSS value must be initialized in the TCPCB 1939 * before this routine is called! 1940 */ 1941 void 1942 tcp_mss_from_peer(struct tcpcb *tp, int offer) 1943 { 1944 struct socket *so; 1945 #if defined(RTV_SPIPE) || defined(RTV_SSTHRESH) 1946 struct rtentry *rt; 1947 #endif 1948 u_long bufsize; 1949 int mss; 1950 1951 #ifdef DIAGNOSTIC 1952 if (tp->t_inpcb && tp->t_in6pcb) 1953 panic("tcp_mss_from_peer: both t_inpcb and t_in6pcb are set"); 1954 #endif 1955 so = NULL; 1956 rt = NULL; 1957 #ifdef INET 1958 if (tp->t_inpcb) { 1959 so = tp->t_inpcb->inp_socket; 1960 #if defined(RTV_SPIPE) || defined(RTV_SSTHRESH) 1961 rt = in_pcbrtentry(tp->t_inpcb); 1962 #endif 1963 } 1964 #endif 1965 #ifdef INET6 1966 if (tp->t_in6pcb) { 1967 so = tp->t_in6pcb->in6p_socket; 1968 #if defined(RTV_SPIPE) || defined(RTV_SSTHRESH) 1969 rt = in6_pcbrtentry(tp->t_in6pcb); 1970 #endif 1971 } 1972 #endif 1973 1974 /* 1975 * As per RFC1122, use the default MSS value, unless they 1976 * sent us an offer. Do not accept offers less than 256 bytes. 1977 */ 1978 mss = tcp_mssdflt; 1979 if (offer) 1980 mss = offer; 1981 mss = max(mss, 256); /* sanity */ 1982 tp->t_peermss = mss; 1983 mss -= tcp_optlen(tp); 1984 #ifdef INET 1985 if (tp->t_inpcb) 1986 mss -= ip_optlen(tp->t_inpcb); 1987 #endif 1988 #ifdef INET6 1989 if (tp->t_in6pcb) 1990 mss -= ip6_optlen(tp->t_in6pcb); 1991 #endif 1992 1993 /* 1994 * If there's a pipesize, change the socket buffer to that size. 1995 * Make the socket buffer an integral number of MSS units. If 1996 * the MSS is larger than the socket buffer, artificially decrease 1997 * the MSS. 1998 */ 1999 #ifdef RTV_SPIPE 2000 if (rt != NULL && rt->rt_rmx.rmx_sendpipe != 0) 2001 bufsize = rt->rt_rmx.rmx_sendpipe; 2002 else 2003 #endif 2004 { 2005 KASSERT(so != NULL); 2006 bufsize = so->so_snd.sb_hiwat; 2007 } 2008 if (bufsize < mss) 2009 mss = bufsize; 2010 else { 2011 bufsize = roundup(bufsize, mss); 2012 if (bufsize > sb_max) 2013 bufsize = sb_max; 2014 (void) sbreserve(&so->so_snd, bufsize, so); 2015 } 2016 tp->t_segsz = mss; 2017 2018 #ifdef RTV_SSTHRESH 2019 if (rt != NULL && rt->rt_rmx.rmx_ssthresh) { 2020 /* 2021 * There's some sort of gateway or interface buffer 2022 * limit on the path. Use this to set the slow 2023 * start threshold, but set the threshold to no less 2024 * than 2 * MSS. 2025 */ 2026 tp->snd_ssthresh = max(2 * mss, rt->rt_rmx.rmx_ssthresh); 2027 } 2028 #endif 2029 } 2030 2031 /* 2032 * Processing necessary when a TCP connection is established. 2033 */ 2034 void 2035 tcp_established(struct tcpcb *tp) 2036 { 2037 struct socket *so; 2038 #ifdef RTV_RPIPE 2039 struct rtentry *rt; 2040 #endif 2041 u_long bufsize; 2042 2043 #ifdef DIAGNOSTIC 2044 if (tp->t_inpcb && tp->t_in6pcb) 2045 panic("tcp_established: both t_inpcb and t_in6pcb are set"); 2046 #endif 2047 so = NULL; 2048 rt = NULL; 2049 #ifdef INET 2050 /* This is a while() to reduce the dreadful stairstepping below */ 2051 while (tp->t_inpcb) { 2052 so = tp->t_inpcb->inp_socket; 2053 #if defined(RTV_RPIPE) 2054 rt = in_pcbrtentry(tp->t_inpcb); 2055 #endif 2056 if (__predict_true(tcp_msl_enable)) { 2057 if (tp->t_inpcb->inp_laddr.s_addr == INADDR_LOOPBACK) { 2058 tp->t_msl = tcp_msl_loop ? tcp_msl_loop : (TCPTV_MSL >> 2); 2059 break; 2060 } 2061 2062 if (__predict_false(tcp_rttlocal)) { 2063 /* This may be adjusted by tcp_input */ 2064 tp->t_msl = tcp_msl_local ? tcp_msl_local : (TCPTV_MSL >> 1); 2065 break; 2066 } 2067 if (in_localaddr(tp->t_inpcb->inp_faddr)) { 2068 tp->t_msl = tcp_msl_local ? tcp_msl_local : (TCPTV_MSL >> 1); 2069 break; 2070 } 2071 } 2072 tp->t_msl = tcp_msl_remote ? tcp_msl_remote : TCPTV_MSL; 2073 break; 2074 } 2075 #endif 2076 #ifdef INET6 2077 /* The !tp->t_inpcb lets the compiler know it can't be v4 *and* v6 */ 2078 while (!tp->t_inpcb && tp->t_in6pcb) { 2079 so = tp->t_in6pcb->in6p_socket; 2080 #if defined(RTV_RPIPE) 2081 rt = in6_pcbrtentry(tp->t_in6pcb); 2082 #endif 2083 if (__predict_true(tcp_msl_enable)) { 2084 extern const struct in6_addr in6addr_loopback; 2085 2086 if (IN6_ARE_ADDR_EQUAL(&tp->t_in6pcb->in6p_laddr, 2087 &in6addr_loopback)) { 2088 tp->t_msl = tcp_msl_loop ? tcp_msl_loop : (TCPTV_MSL >> 2); 2089 break; 2090 } 2091 2092 if (__predict_false(tcp_rttlocal)) { 2093 /* This may be adjusted by tcp_input */ 2094 tp->t_msl = tcp_msl_local ? tcp_msl_local : (TCPTV_MSL >> 1); 2095 break; 2096 } 2097 if (in6_localaddr(&tp->t_in6pcb->in6p_faddr)) { 2098 tp->t_msl = tcp_msl_local ? tcp_msl_local : (TCPTV_MSL >> 1); 2099 break; 2100 } 2101 } 2102 tp->t_msl = tcp_msl_remote ? tcp_msl_remote : TCPTV_MSL; 2103 break; 2104 } 2105 #endif 2106 2107 tp->t_state = TCPS_ESTABLISHED; 2108 TCP_TIMER_ARM(tp, TCPT_KEEP, tp->t_keepidle); 2109 2110 #ifdef RTV_RPIPE 2111 if (rt != NULL && rt->rt_rmx.rmx_recvpipe != 0) 2112 bufsize = rt->rt_rmx.rmx_recvpipe; 2113 else 2114 #endif 2115 { 2116 KASSERT(so != NULL); 2117 bufsize = so->so_rcv.sb_hiwat; 2118 } 2119 if (bufsize > tp->t_ourmss) { 2120 bufsize = roundup(bufsize, tp->t_ourmss); 2121 if (bufsize > sb_max) 2122 bufsize = sb_max; 2123 (void) sbreserve(&so->so_rcv, bufsize, so); 2124 } 2125 } 2126 2127 /* 2128 * Check if there's an initial rtt or rttvar. Convert from the 2129 * route-table units to scaled multiples of the slow timeout timer. 2130 * Called only during the 3-way handshake. 2131 */ 2132 void 2133 tcp_rmx_rtt(struct tcpcb *tp) 2134 { 2135 #ifdef RTV_RTT 2136 struct rtentry *rt = NULL; 2137 int rtt; 2138 2139 #ifdef DIAGNOSTIC 2140 if (tp->t_inpcb && tp->t_in6pcb) 2141 panic("tcp_rmx_rtt: both t_inpcb and t_in6pcb are set"); 2142 #endif 2143 #ifdef INET 2144 if (tp->t_inpcb) 2145 rt = in_pcbrtentry(tp->t_inpcb); 2146 #endif 2147 #ifdef INET6 2148 if (tp->t_in6pcb) 2149 rt = in6_pcbrtentry(tp->t_in6pcb); 2150 #endif 2151 if (rt == NULL) 2152 return; 2153 2154 if (tp->t_srtt == 0 && (rtt = rt->rt_rmx.rmx_rtt)) { 2155 /* 2156 * XXX The lock bit for MTU indicates that the value 2157 * is also a minimum value; this is subject to time. 2158 */ 2159 if (rt->rt_rmx.rmx_locks & RTV_RTT) 2160 TCPT_RANGESET(tp->t_rttmin, 2161 rtt / (RTM_RTTUNIT / PR_SLOWHZ), 2162 TCPTV_MIN, TCPTV_REXMTMAX); 2163 tp->t_srtt = rtt / 2164 ((RTM_RTTUNIT / PR_SLOWHZ) >> (TCP_RTT_SHIFT + 2)); 2165 if (rt->rt_rmx.rmx_rttvar) { 2166 tp->t_rttvar = rt->rt_rmx.rmx_rttvar / 2167 ((RTM_RTTUNIT / PR_SLOWHZ) >> 2168 (TCP_RTTVAR_SHIFT + 2)); 2169 } else { 2170 /* Default variation is +- 1 rtt */ 2171 tp->t_rttvar = 2172 tp->t_srtt >> (TCP_RTT_SHIFT - TCP_RTTVAR_SHIFT); 2173 } 2174 TCPT_RANGESET(tp->t_rxtcur, 2175 ((tp->t_srtt >> 2) + tp->t_rttvar) >> (1 + 2), 2176 tp->t_rttmin, TCPTV_REXMTMAX); 2177 } 2178 #endif 2179 } 2180 2181 tcp_seq tcp_iss_seq = 0; /* tcp initial seq # */ 2182 #if NRND > 0 2183 u_int8_t tcp_iss_secret[16]; /* 128 bits; should be plenty */ 2184 #endif 2185 2186 /* 2187 * Get a new sequence value given a tcp control block 2188 */ 2189 tcp_seq 2190 tcp_new_iss(struct tcpcb *tp, tcp_seq addin) 2191 { 2192 2193 #ifdef INET 2194 if (tp->t_inpcb != NULL) { 2195 return (tcp_new_iss1(&tp->t_inpcb->inp_laddr, 2196 &tp->t_inpcb->inp_faddr, tp->t_inpcb->inp_lport, 2197 tp->t_inpcb->inp_fport, sizeof(tp->t_inpcb->inp_laddr), 2198 addin)); 2199 } 2200 #endif 2201 #ifdef INET6 2202 if (tp->t_in6pcb != NULL) { 2203 return (tcp_new_iss1(&tp->t_in6pcb->in6p_laddr, 2204 &tp->t_in6pcb->in6p_faddr, tp->t_in6pcb->in6p_lport, 2205 tp->t_in6pcb->in6p_fport, sizeof(tp->t_in6pcb->in6p_laddr), 2206 addin)); 2207 } 2208 #endif 2209 /* Not possible. */ 2210 panic("tcp_new_iss"); 2211 } 2212 2213 /* 2214 * This routine actually generates a new TCP initial sequence number. 2215 */ 2216 tcp_seq 2217 tcp_new_iss1(void *laddr, void *faddr, u_int16_t lport, u_int16_t fport, 2218 size_t addrsz, tcp_seq addin) 2219 { 2220 tcp_seq tcp_iss; 2221 2222 #if NRND > 0 2223 static bool tcp_iss_gotten_secret; 2224 2225 /* 2226 * If we haven't been here before, initialize our cryptographic 2227 * hash secret. 2228 */ 2229 if (tcp_iss_gotten_secret == false) { 2230 rnd_extract_data(tcp_iss_secret, sizeof(tcp_iss_secret), 2231 RND_EXTRACT_ANY); 2232 tcp_iss_gotten_secret = true; 2233 } 2234 2235 if (tcp_do_rfc1948) { 2236 MD5_CTX ctx; 2237 u_int8_t hash[16]; /* XXX MD5 knowledge */ 2238 2239 /* 2240 * Compute the base value of the ISS. It is a hash 2241 * of (saddr, sport, daddr, dport, secret). 2242 */ 2243 MD5Init(&ctx); 2244 2245 MD5Update(&ctx, (u_char *) laddr, addrsz); 2246 MD5Update(&ctx, (u_char *) &lport, sizeof(lport)); 2247 2248 MD5Update(&ctx, (u_char *) faddr, addrsz); 2249 MD5Update(&ctx, (u_char *) &fport, sizeof(fport)); 2250 2251 MD5Update(&ctx, tcp_iss_secret, sizeof(tcp_iss_secret)); 2252 2253 MD5Final(hash, &ctx); 2254 2255 memcpy(&tcp_iss, hash, sizeof(tcp_iss)); 2256 2257 /* 2258 * Now increment our "timer", and add it in to 2259 * the computed value. 2260 * 2261 * XXX Use `addin'? 2262 * XXX TCP_ISSINCR too large to use? 2263 */ 2264 tcp_iss_seq += TCP_ISSINCR; 2265 #ifdef TCPISS_DEBUG 2266 printf("ISS hash 0x%08x, ", tcp_iss); 2267 #endif 2268 tcp_iss += tcp_iss_seq + addin; 2269 #ifdef TCPISS_DEBUG 2270 printf("new ISS 0x%08x\n", tcp_iss); 2271 #endif 2272 } else 2273 #endif /* NRND > 0 */ 2274 { 2275 /* 2276 * Randomize. 2277 */ 2278 #if NRND > 0 2279 rnd_extract_data(&tcp_iss, sizeof(tcp_iss), RND_EXTRACT_ANY); 2280 #else 2281 tcp_iss = arc4random(); 2282 #endif 2283 2284 /* 2285 * If we were asked to add some amount to a known value, 2286 * we will take a random value obtained above, mask off 2287 * the upper bits, and add in the known value. We also 2288 * add in a constant to ensure that we are at least a 2289 * certain distance from the original value. 2290 * 2291 * This is used when an old connection is in timed wait 2292 * and we have a new one coming in, for instance. 2293 */ 2294 if (addin != 0) { 2295 #ifdef TCPISS_DEBUG 2296 printf("Random %08x, ", tcp_iss); 2297 #endif 2298 tcp_iss &= TCP_ISS_RANDOM_MASK; 2299 tcp_iss += addin + TCP_ISSINCR; 2300 #ifdef TCPISS_DEBUG 2301 printf("Old ISS %08x, ISS %08x\n", addin, tcp_iss); 2302 #endif 2303 } else { 2304 tcp_iss &= TCP_ISS_RANDOM_MASK; 2305 tcp_iss += tcp_iss_seq; 2306 tcp_iss_seq += TCP_ISSINCR; 2307 #ifdef TCPISS_DEBUG 2308 printf("ISS %08x\n", tcp_iss); 2309 #endif 2310 } 2311 } 2312 2313 if (tcp_compat_42) { 2314 /* 2315 * Limit it to the positive range for really old TCP 2316 * implementations. 2317 * Just AND off the top bit instead of checking if 2318 * is set first - saves a branch 50% of the time. 2319 */ 2320 tcp_iss &= 0x7fffffff; /* XXX */ 2321 } 2322 2323 return (tcp_iss); 2324 } 2325 2326 #if defined(IPSEC) || defined(FAST_IPSEC) 2327 /* compute ESP/AH header size for TCP, including outer IP header. */ 2328 size_t 2329 ipsec4_hdrsiz_tcp(struct tcpcb *tp) 2330 { 2331 struct inpcb *inp; 2332 size_t hdrsiz; 2333 2334 /* XXX mapped addr case (tp->t_in6pcb) */ 2335 if (!tp || !tp->t_template || !(inp = tp->t_inpcb)) 2336 return 0; 2337 switch (tp->t_family) { 2338 case AF_INET: 2339 /* XXX: should use currect direction. */ 2340 hdrsiz = ipsec4_hdrsiz(tp->t_template, IPSEC_DIR_OUTBOUND, inp); 2341 break; 2342 default: 2343 hdrsiz = 0; 2344 break; 2345 } 2346 2347 return hdrsiz; 2348 } 2349 2350 #ifdef INET6 2351 size_t 2352 ipsec6_hdrsiz_tcp(struct tcpcb *tp) 2353 { 2354 struct in6pcb *in6p; 2355 size_t hdrsiz; 2356 2357 if (!tp || !tp->t_template || !(in6p = tp->t_in6pcb)) 2358 return 0; 2359 switch (tp->t_family) { 2360 case AF_INET6: 2361 /* XXX: should use currect direction. */ 2362 hdrsiz = ipsec6_hdrsiz(tp->t_template, IPSEC_DIR_OUTBOUND, in6p); 2363 break; 2364 case AF_INET: 2365 /* mapped address case - tricky */ 2366 default: 2367 hdrsiz = 0; 2368 break; 2369 } 2370 2371 return hdrsiz; 2372 } 2373 #endif 2374 #endif /*IPSEC*/ 2375 2376 /* 2377 * Determine the length of the TCP options for this connection. 2378 * 2379 * XXX: What do we do for SACK, when we add that? Just reserve 2380 * all of the space? Otherwise we can't exactly be incrementing 2381 * cwnd by an amount that varies depending on the amount we last 2382 * had to SACK! 2383 */ 2384 2385 u_int 2386 tcp_optlen(struct tcpcb *tp) 2387 { 2388 u_int optlen; 2389 2390 optlen = 0; 2391 if ((tp->t_flags & (TF_REQ_TSTMP|TF_RCVD_TSTMP|TF_NOOPT)) == 2392 (TF_REQ_TSTMP | TF_RCVD_TSTMP)) 2393 optlen += TCPOLEN_TSTAMP_APPA; 2394 2395 #ifdef TCP_SIGNATURE 2396 if (tp->t_flags & TF_SIGNATURE) 2397 optlen += TCPOLEN_SIGNATURE + 2; 2398 #endif /* TCP_SIGNATURE */ 2399 2400 return optlen; 2401 } 2402 2403 u_int 2404 tcp_hdrsz(struct tcpcb *tp) 2405 { 2406 u_int hlen; 2407 2408 switch (tp->t_family) { 2409 #ifdef INET6 2410 case AF_INET6: 2411 hlen = sizeof(struct ip6_hdr); 2412 break; 2413 #endif 2414 case AF_INET: 2415 hlen = sizeof(struct ip); 2416 break; 2417 default: 2418 hlen = 0; 2419 break; 2420 } 2421 hlen += sizeof(struct tcphdr); 2422 2423 if ((tp->t_flags & (TF_REQ_TSTMP|TF_NOOPT)) == TF_REQ_TSTMP && 2424 (tp->t_flags & TF_RCVD_TSTMP) == TF_RCVD_TSTMP) 2425 hlen += TCPOLEN_TSTAMP_APPA; 2426 #ifdef TCP_SIGNATURE 2427 if (tp->t_flags & TF_SIGNATURE) 2428 hlen += TCPOLEN_SIGLEN; 2429 #endif 2430 return hlen; 2431 } 2432 2433 void 2434 tcp_statinc(u_int stat) 2435 { 2436 2437 KASSERT(stat < TCP_NSTATS); 2438 TCP_STATINC(stat); 2439 } 2440 2441 void 2442 tcp_statadd(u_int stat, uint64_t val) 2443 { 2444 2445 KASSERT(stat < TCP_NSTATS); 2446 TCP_STATADD(stat, val); 2447 } 2448
Indexes created Sun Sep 21 14:09:52 GMT 2025