1 /*- 2 * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 4. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * @(#)tcp_subr.c 8.2 (Berkeley) 5/24/95 30 */ 31 32 #include <sys/cdefs.h> 33 __FBSDID("$FreeBSD$"); 34 35 #include "opt_compat.h" 36 #include "opt_inet.h" 37 #include "opt_inet6.h" 38 #include "opt_ipsec.h" 39 #include "opt_tcpdebug.h" 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/callout.h> 44 #include <sys/hhook.h> 45 #include <sys/kernel.h> 46 #include <sys/khelp.h> 47 #include <sys/sysctl.h> 48 #include <sys/jail.h> 49 #include <sys/malloc.h> 50 #include <sys/mbuf.h> 51 #ifdef INET6 52 #include <sys/domain.h> 53 #endif 54 #include <sys/priv.h> 55 #include <sys/proc.h> 56 #include <sys/sdt.h> 57 #include <sys/socket.h> 58 #include <sys/socketvar.h> 59 #include <sys/protosw.h> 60 #include <sys/random.h> 61 62 #include <vm/uma.h> 63 64 #include <net/route.h> 65 #include <net/if.h> 66 #include <net/if_var.h> 67 #include <net/vnet.h> 68 69 #include <netinet/cc.h> 70 #include <netinet/in.h> 71 #include <netinet/in_kdtrace.h> 72 #include <netinet/in_pcb.h> 73 #include <netinet/in_systm.h> 74 #include <netinet/in_var.h> 75 #include <netinet/ip.h> 76 #include <netinet/ip_icmp.h> 77 #include <netinet/ip_var.h> 78 #ifdef INET6 79 #include <netinet/ip6.h> 80 #include <netinet6/in6_pcb.h> 81 #include <netinet6/ip6_var.h> 82 #include <netinet6/scope6_var.h> 83 #include <netinet6/nd6.h> 84 #endif 85 86 #include <netinet/tcp_fsm.h> 87 #include <netinet/tcp_seq.h> 88 #include <netinet/tcp_timer.h> 89 #include <netinet/tcp_var.h> 90 #include <netinet/tcp_syncache.h> 91 #ifdef INET6 92 #include <netinet6/tcp6_var.h> 93 #endif 94 #include <netinet/tcpip.h> 95 #ifdef TCPDEBUG 96 #include <netinet/tcp_debug.h> 97 #endif 98 #ifdef INET6 99 #include <netinet6/ip6protosw.h> 100 #endif 101 #ifdef TCP_OFFLOAD 102 #include <netinet/tcp_offload.h> 103 #endif 104 105 #ifdef IPSEC 106 #include <netipsec/ipsec.h> 107 #include <netipsec/xform.h> 108 #ifdef INET6 109 #include <netipsec/ipsec6.h> 110 #endif 111 #include <netipsec/key.h> 112 #include <sys/syslog.h> 113 #endif /*IPSEC*/ 114 115 #include <machine/in_cksum.h> 116 #include <sys/md5.h> 117 118 #include <security/mac/mac_framework.h> 119 120 VNET_DEFINE(int, tcp_mssdflt) = TCP_MSS; 121 #ifdef INET6 122 VNET_DEFINE(int, tcp_v6mssdflt) = TCP6_MSS; 123 #endif 124 125 static int 126 sysctl_net_inet_tcp_mss_check(SYSCTL_HANDLER_ARGS) 127 { 128 int error, new; 129 130 new = V_tcp_mssdflt; 131 error = sysctl_handle_int(oidp, &new, 0, req); 132 if (error == 0 && req->newptr) { 133 if (new < TCP_MINMSS) 134 error = EINVAL; 135 else 136 V_tcp_mssdflt = new; 137 } 138 return (error); 139 } 140 141 SYSCTL_VNET_PROC(_net_inet_tcp, TCPCTL_MSSDFLT, mssdflt, 142 CTLTYPE_INT|CTLFLAG_RW, &VNET_NAME(tcp_mssdflt), 0, 143 &sysctl_net_inet_tcp_mss_check, "I", 144 "Default TCP Maximum Segment Size"); 145 146 #ifdef INET6 147 static int 148 sysctl_net_inet_tcp_mss_v6_check(SYSCTL_HANDLER_ARGS) 149 { 150 int error, new; 151 152 new = V_tcp_v6mssdflt; 153 error = sysctl_handle_int(oidp, &new, 0, req); 154 if (error == 0 && req->newptr) { 155 if (new < TCP_MINMSS) 156 error = EINVAL; 157 else 158 V_tcp_v6mssdflt = new; 159 } 160 return (error); 161 } 162 163 SYSCTL_VNET_PROC(_net_inet_tcp, TCPCTL_V6MSSDFLT, v6mssdflt, 164 CTLTYPE_INT|CTLFLAG_RW, &VNET_NAME(tcp_v6mssdflt), 0, 165 &sysctl_net_inet_tcp_mss_v6_check, "I", 166 "Default TCP Maximum Segment Size for IPv6"); 167 #endif /* INET6 */ 168 169 /* 170 * Minimum MSS we accept and use. This prevents DoS attacks where 171 * we are forced to a ridiculous low MSS like 20 and send hundreds 172 * of packets instead of one. The effect scales with the available 173 * bandwidth and quickly saturates the CPU and network interface 174 * with packet generation and sending. Set to zero to disable MINMSS 175 * checking. This setting prevents us from sending too small packets. 176 */ 177 VNET_DEFINE(int, tcp_minmss) = TCP_MINMSS; 178 SYSCTL_VNET_INT(_net_inet_tcp, OID_AUTO, minmss, CTLFLAG_RW, 179 &VNET_NAME(tcp_minmss), 0, 180 "Minimum TCP Maximum Segment Size"); 181 182 VNET_DEFINE(int, tcp_do_rfc1323) = 1; 183 SYSCTL_VNET_INT(_net_inet_tcp, TCPCTL_DO_RFC1323, rfc1323, CTLFLAG_RW, 184 &VNET_NAME(tcp_do_rfc1323), 0, 185 "Enable rfc1323 (high performance TCP) extensions"); 186 187 static int tcp_log_debug = 0; 188 SYSCTL_INT(_net_inet_tcp, OID_AUTO, log_debug, CTLFLAG_RW, 189 &tcp_log_debug, 0, "Log errors caused by incoming TCP segments"); 190 191 static int tcp_tcbhashsize = 0; 192 SYSCTL_INT(_net_inet_tcp, OID_AUTO, tcbhashsize, CTLFLAG_RDTUN, 193 &tcp_tcbhashsize, 0, "Size of TCP control-block hashtable"); 194 195 static int do_tcpdrain = 1; 196 SYSCTL_INT(_net_inet_tcp, OID_AUTO, do_tcpdrain, CTLFLAG_RW, &do_tcpdrain, 0, 197 "Enable tcp_drain routine for extra help when low on mbufs"); 198 199 SYSCTL_VNET_UINT(_net_inet_tcp, OID_AUTO, pcbcount, CTLFLAG_RD, 200 &VNET_NAME(tcbinfo.ipi_count), 0, "Number of active PCBs"); 201 202 static VNET_DEFINE(int, icmp_may_rst) = 1; 203 #define V_icmp_may_rst VNET(icmp_may_rst) 204 SYSCTL_VNET_INT(_net_inet_tcp, OID_AUTO, icmp_may_rst, CTLFLAG_RW, 205 &VNET_NAME(icmp_may_rst), 0, 206 "Certain ICMP unreachable messages may abort connections in SYN_SENT"); 207 208 static VNET_DEFINE(int, tcp_isn_reseed_interval) = 0; 209 #define V_tcp_isn_reseed_interval VNET(tcp_isn_reseed_interval) 210 SYSCTL_VNET_INT(_net_inet_tcp, OID_AUTO, isn_reseed_interval, CTLFLAG_RW, 211 &VNET_NAME(tcp_isn_reseed_interval), 0, 212 "Seconds between reseeding of ISN secret"); 213 214 static int tcp_soreceive_stream = 0; 215 SYSCTL_INT(_net_inet_tcp, OID_AUTO, soreceive_stream, CTLFLAG_RDTUN, 216 &tcp_soreceive_stream, 0, "Using soreceive_stream for TCP sockets"); 217 218 #ifdef TCP_SIGNATURE 219 static int tcp_sig_checksigs = 1; 220 SYSCTL_INT(_net_inet_tcp, OID_AUTO, signature_verify_input, CTLFLAG_RW, 221 &tcp_sig_checksigs, 0, "Verify RFC2385 digests on inbound traffic"); 222 #endif 223 224 VNET_DEFINE(uma_zone_t, sack_hole_zone); 225 #define V_sack_hole_zone VNET(sack_hole_zone) 226 227 VNET_DEFINE(struct hhook_head *, tcp_hhh[HHOOK_TCP_LAST+1]); 228 229 static struct inpcb *tcp_notify(struct inpcb *, int); 230 static struct inpcb *tcp_mtudisc_notify(struct inpcb *, int); 231 static char * tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th, 232 void *ip4hdr, const void *ip6hdr); 233 234 /* 235 * Target size of TCP PCB hash tables. Must be a power of two. 236 * 237 * Note that this can be overridden by the kernel environment 238 * variable net.inet.tcp.tcbhashsize 239 */ 240 #ifndef TCBHASHSIZE 241 #define TCBHASHSIZE 0 242 #endif 243 244 /* 245 * XXX 246 * Callouts should be moved into struct tcp directly. They are currently 247 * separate because the tcpcb structure is exported to userland for sysctl 248 * parsing purposes, which do not know about callouts. 249 */ 250 struct tcpcb_mem { 251 struct tcpcb tcb; 252 struct tcp_timer tt; 253 struct cc_var ccv; 254 struct osd osd; 255 }; 256 257 static VNET_DEFINE(uma_zone_t, tcpcb_zone); 258 #define V_tcpcb_zone VNET(tcpcb_zone) 259 260 MALLOC_DEFINE(M_TCPLOG, "tcplog", "TCP address and flags print buffers"); 261 static struct mtx isn_mtx; 262 263 #define ISN_LOCK_INIT() mtx_init(&isn_mtx, "isn_mtx", NULL, MTX_DEF) 264 #define ISN_LOCK() mtx_lock(&isn_mtx) 265 #define ISN_UNLOCK() mtx_unlock(&isn_mtx) 266 267 /* 268 * TCP initialization. 269 */ 270 static void 271 tcp_zone_change(void *tag) 272 { 273 274 uma_zone_set_max(V_tcbinfo.ipi_zone, maxsockets); 275 uma_zone_set_max(V_tcpcb_zone, maxsockets); 276 tcp_tw_zone_change(); 277 } 278 279 static int 280 tcp_inpcb_init(void *mem, int size, int flags) 281 { 282 struct inpcb *inp = mem; 283 284 INP_LOCK_INIT(inp, "inp", "tcpinp"); 285 return (0); 286 } 287 288 /* 289 * Take a value and get the next power of 2 that doesn't overflow. 290 * Used to size the tcp_inpcb hash buckets. 291 */ 292 static int 293 maketcp_hashsize(int size) 294 { 295 int hashsize; 296 297 /* 298 * auto tune. 299 * get the next power of 2 higher than maxsockets. 300 */ 301 hashsize = 1 << fls(size); 302 /* catch overflow, and just go one power of 2 smaller */ 303 if (hashsize < size) { 304 hashsize = 1 << (fls(size) - 1); 305 } 306 return (hashsize); 307 } 308 309 void 310 tcp_init(void) 311 { 312 const char *tcbhash_tuneable; 313 int hashsize; 314 315 tcbhash_tuneable = "net.inet.tcp.tcbhashsize"; 316 317 if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN, 318 &V_tcp_hhh[HHOOK_TCP_EST_IN], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0) 319 printf("%s: WARNING: unable to register helper hook\n", __func__); 320 if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT, 321 &V_tcp_hhh[HHOOK_TCP_EST_OUT], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0) 322 printf("%s: WARNING: unable to register helper hook\n", __func__); 323 324 hashsize = TCBHASHSIZE; 325 TUNABLE_INT_FETCH(tcbhash_tuneable, &hashsize); 326 if (hashsize == 0) { 327 /* 328 * Auto tune the hash size based on maxsockets. 329 * A perfect hash would have a 1:1 mapping 330 * (hashsize = maxsockets) however it's been 331 * suggested that O(2) average is better. 332 */ 333 hashsize = maketcp_hashsize(maxsockets / 4); 334 /* 335 * Our historical default is 512, 336 * do not autotune lower than this. 337 */ 338 if (hashsize < 512) 339 hashsize = 512; 340 if (bootverbose) 341 printf("%s: %s auto tuned to %d\n", __func__, 342 tcbhash_tuneable, hashsize); 343 } 344 /* 345 * We require a hashsize to be a power of two. 346 * Previously if it was not a power of two we would just reset it 347 * back to 512, which could be a nasty surprise if you did not notice 348 * the error message. 349 * Instead what we do is clip it to the closest power of two lower 350 * than the specified hash value. 351 */ 352 if (!powerof2(hashsize)) { 353 int oldhashsize = hashsize; 354 355 hashsize = maketcp_hashsize(hashsize); 356 /* prevent absurdly low value */ 357 if (hashsize < 16) 358 hashsize = 16; 359 printf("%s: WARNING: TCB hash size not a power of 2, " 360 "clipped from %d to %d.\n", __func__, oldhashsize, 361 hashsize); 362 } 363 in_pcbinfo_init(&V_tcbinfo, "tcp", &V_tcb, hashsize, hashsize, 364 "tcp_inpcb", tcp_inpcb_init, NULL, UMA_ZONE_NOFREE, 365 IPI_HASHFIELDS_4TUPLE); 366 367 /* 368 * These have to be type stable for the benefit of the timers. 369 */ 370 V_tcpcb_zone = uma_zcreate("tcpcb", sizeof(struct tcpcb_mem), 371 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 372 uma_zone_set_max(V_tcpcb_zone, maxsockets); 373 uma_zone_set_warning(V_tcpcb_zone, "kern.ipc.maxsockets limit reached"); 374 375 tcp_tw_init(); 376 syncache_init(); 377 tcp_hc_init(); 378 379 TUNABLE_INT_FETCH("net.inet.tcp.sack.enable", &V_tcp_do_sack); 380 V_sack_hole_zone = uma_zcreate("sackhole", sizeof(struct sackhole), 381 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 382 383 /* Skip initialization of globals for non-default instances. */ 384 if (!IS_DEFAULT_VNET(curvnet)) 385 return; 386 387 /* XXX virtualize those bellow? */ 388 tcp_delacktime = TCPTV_DELACK; 389 tcp_keepinit = TCPTV_KEEP_INIT; 390 tcp_keepidle = TCPTV_KEEP_IDLE; 391 tcp_keepintvl = TCPTV_KEEPINTVL; 392 tcp_maxpersistidle = TCPTV_KEEP_IDLE; 393 tcp_msl = TCPTV_MSL; 394 tcp_rexmit_min = TCPTV_MIN; 395 if (tcp_rexmit_min < 1) 396 tcp_rexmit_min = 1; 397 tcp_rexmit_slop = TCPTV_CPU_VAR; 398 tcp_finwait2_timeout = TCPTV_FINWAIT2_TIMEOUT; 399 tcp_tcbhashsize = hashsize; 400 401 TUNABLE_INT_FETCH("net.inet.tcp.soreceive_stream", &tcp_soreceive_stream); 402 if (tcp_soreceive_stream) { 403 #ifdef INET 404 tcp_usrreqs.pru_soreceive = soreceive_stream; 405 #endif 406 #ifdef INET6 407 tcp6_usrreqs.pru_soreceive = soreceive_stream; 408 #endif /* INET6 */ 409 } 410 411 #ifdef INET6 412 #define TCP_MINPROTOHDR (sizeof(struct ip6_hdr) + sizeof(struct tcphdr)) 413 #else /* INET6 */ 414 #define TCP_MINPROTOHDR (sizeof(struct tcpiphdr)) 415 #endif /* INET6 */ 416 if (max_protohdr < TCP_MINPROTOHDR) 417 max_protohdr = TCP_MINPROTOHDR; 418 if (max_linkhdr + TCP_MINPROTOHDR > MHLEN) 419 panic("tcp_init"); 420 #undef TCP_MINPROTOHDR 421 422 ISN_LOCK_INIT(); 423 EVENTHANDLER_REGISTER(shutdown_pre_sync, tcp_fini, NULL, 424 SHUTDOWN_PRI_DEFAULT); 425 EVENTHANDLER_REGISTER(maxsockets_change, tcp_zone_change, NULL, 426 EVENTHANDLER_PRI_ANY); 427 } 428 429 #ifdef VIMAGE 430 void 431 tcp_destroy(void) 432 { 433 int error; 434 435 tcp_hc_destroy(); 436 syncache_destroy(); 437 tcp_tw_destroy(); 438 in_pcbinfo_destroy(&V_tcbinfo); 439 uma_zdestroy(V_sack_hole_zone); 440 uma_zdestroy(V_tcpcb_zone); 441 442 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_IN]); 443 if (error != 0) { 444 printf("%s: WARNING: unable to deregister helper hook " 445 "type=%d, id=%d: error %d returned\n", __func__, 446 HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN, error); 447 } 448 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_OUT]); 449 if (error != 0) { 450 printf("%s: WARNING: unable to deregister helper hook " 451 "type=%d, id=%d: error %d returned\n", __func__, 452 HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT, error); 453 } 454 } 455 #endif 456 457 void 458 tcp_fini(void *xtp) 459 { 460 461 } 462 463 /* 464 * Fill in the IP and TCP headers for an outgoing packet, given the tcpcb. 465 * tcp_template used to store this data in mbufs, but we now recopy it out 466 * of the tcpcb each time to conserve mbufs. 467 */ 468 void 469 tcpip_fillheaders(struct inpcb *inp, void *ip_ptr, void *tcp_ptr) 470 { 471 struct tcphdr *th = (struct tcphdr *)tcp_ptr; 472 473 INP_WLOCK_ASSERT(inp); 474 475 #ifdef INET6 476 if ((inp->inp_vflag & INP_IPV6) != 0) { 477 struct ip6_hdr *ip6; 478 479 ip6 = (struct ip6_hdr *)ip_ptr; 480 ip6->ip6_flow = (ip6->ip6_flow & ~IPV6_FLOWINFO_MASK) | 481 (inp->inp_flow & IPV6_FLOWINFO_MASK); 482 ip6->ip6_vfc = (ip6->ip6_vfc & ~IPV6_VERSION_MASK) | 483 (IPV6_VERSION & IPV6_VERSION_MASK); 484 ip6->ip6_nxt = IPPROTO_TCP; 485 ip6->ip6_plen = htons(sizeof(struct tcphdr)); 486 ip6->ip6_src = inp->in6p_laddr; 487 ip6->ip6_dst = inp->in6p_faddr; 488 } 489 #endif /* INET6 */ 490 #if defined(INET6) && defined(INET) 491 else 492 #endif 493 #ifdef INET 494 { 495 struct ip *ip; 496 497 ip = (struct ip *)ip_ptr; 498 ip->ip_v = IPVERSION; 499 ip->ip_hl = 5; 500 ip->ip_tos = inp->inp_ip_tos; 501 ip->ip_len = 0; 502 ip->ip_id = 0; 503 ip->ip_off = 0; 504 ip->ip_ttl = inp->inp_ip_ttl; 505 ip->ip_sum = 0; 506 ip->ip_p = IPPROTO_TCP; 507 ip->ip_src = inp->inp_laddr; 508 ip->ip_dst = inp->inp_faddr; 509 } 510 #endif /* INET */ 511 th->th_sport = inp->inp_lport; 512 th->th_dport = inp->inp_fport; 513 th->th_seq = 0; 514 th->th_ack = 0; 515 th->th_x2 = 0; 516 th->th_off = 5; 517 th->th_flags = 0; 518 th->th_win = 0; 519 th->th_urp = 0; 520 th->th_sum = 0; /* in_pseudo() is called later for ipv4 */ 521 } 522 523 /* 524 * Create template to be used to send tcp packets on a connection. 525 * Allocates an mbuf and fills in a skeletal tcp/ip header. The only 526 * use for this function is in keepalives, which use tcp_respond. 527 */ 528 struct tcptemp * 529 tcpip_maketemplate(struct inpcb *inp) 530 { 531 struct tcptemp *t; 532 533 t = malloc(sizeof(*t), M_TEMP, M_NOWAIT); 534 if (t == NULL) 535 return (NULL); 536 tcpip_fillheaders(inp, (void *)&t->tt_ipgen, (void *)&t->tt_t); 537 return (t); 538 } 539 540 /* 541 * Send a single message to the TCP at address specified by 542 * the given TCP/IP header. If m == NULL, then we make a copy 543 * of the tcpiphdr at ti and send directly to the addressed host. 544 * This is used to force keep alive messages out using the TCP 545 * template for a connection. If flags are given then we send 546 * a message back to the TCP which originated the * segment ti, 547 * and discard the mbuf containing it and any other attached mbufs. 548 * 549 * In any case the ack and sequence number of the transmitted 550 * segment are as specified by the parameters. 551 * 552 * NOTE: If m != NULL, then ti must point to *inside* the mbuf. 553 */ 554 void 555 tcp_respond(struct tcpcb *tp, void *ipgen, struct tcphdr *th, struct mbuf *m, 556 tcp_seq ack, tcp_seq seq, int flags) 557 { 558 int tlen; 559 int win = 0; 560 struct ip *ip; 561 struct tcphdr *nth; 562 #ifdef INET6 563 struct ip6_hdr *ip6; 564 int isipv6; 565 #endif /* INET6 */ 566 int ipflags = 0; 567 struct inpcb *inp; 568 569 KASSERT(tp != NULL || m != NULL, ("tcp_respond: tp and m both NULL")); 570 571 #ifdef INET6 572 isipv6 = ((struct ip *)ipgen)->ip_v == (IPV6_VERSION >> 4); 573 ip6 = ipgen; 574 #endif /* INET6 */ 575 ip = ipgen; 576 577 if (tp != NULL) { 578 inp = tp->t_inpcb; 579 KASSERT(inp != NULL, ("tcp control block w/o inpcb")); 580 INP_WLOCK_ASSERT(inp); 581 } else 582 inp = NULL; 583 584 if (tp != NULL) { 585 if (!(flags & TH_RST)) { 586 win = sbspace(&inp->inp_socket->so_rcv); 587 if (win > (long)TCP_MAXWIN << tp->rcv_scale) 588 win = (long)TCP_MAXWIN << tp->rcv_scale; 589 } 590 } 591 if (m == NULL) { 592 m = m_gethdr(M_NOWAIT, MT_DATA); 593 if (m == NULL) 594 return; 595 tlen = 0; 596 m->m_data += max_linkhdr; 597 #ifdef INET6 598 if (isipv6) { 599 bcopy((caddr_t)ip6, mtod(m, caddr_t), 600 sizeof(struct ip6_hdr)); 601 ip6 = mtod(m, struct ip6_hdr *); 602 nth = (struct tcphdr *)(ip6 + 1); 603 } else 604 #endif /* INET6 */ 605 { 606 bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip)); 607 ip = mtod(m, struct ip *); 608 nth = (struct tcphdr *)(ip + 1); 609 } 610 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr)); 611 flags = TH_ACK; 612 } else { 613 /* 614 * reuse the mbuf. 615 * XXX MRT We inherrit the FIB, which is lucky. 616 */ 617 m_freem(m->m_next); 618 m->m_next = NULL; 619 m->m_data = (caddr_t)ipgen; 620 /* m_len is set later */ 621 tlen = 0; 622 #define xchg(a,b,type) { type t; t=a; a=b; b=t; } 623 #ifdef INET6 624 if (isipv6) { 625 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); 626 nth = (struct tcphdr *)(ip6 + 1); 627 } else 628 #endif /* INET6 */ 629 { 630 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t); 631 nth = (struct tcphdr *)(ip + 1); 632 } 633 if (th != nth) { 634 /* 635 * this is usually a case when an extension header 636 * exists between the IPv6 header and the 637 * TCP header. 638 */ 639 nth->th_sport = th->th_sport; 640 nth->th_dport = th->th_dport; 641 } 642 xchg(nth->th_dport, nth->th_sport, uint16_t); 643 #undef xchg 644 } 645 #ifdef INET6 646 if (isipv6) { 647 ip6->ip6_flow = 0; 648 ip6->ip6_vfc = IPV6_VERSION; 649 ip6->ip6_nxt = IPPROTO_TCP; 650 tlen += sizeof (struct ip6_hdr) + sizeof (struct tcphdr); 651 ip6->ip6_plen = htons(tlen - sizeof(*ip6)); 652 } 653 #endif 654 #if defined(INET) && defined(INET6) 655 else 656 #endif 657 #ifdef INET 658 { 659 tlen += sizeof (struct tcpiphdr); 660 ip->ip_len = htons(tlen); 661 ip->ip_ttl = V_ip_defttl; 662 if (V_path_mtu_discovery) 663 ip->ip_off |= htons(IP_DF); 664 } 665 #endif 666 m->m_len = tlen; 667 m->m_pkthdr.len = tlen; 668 m->m_pkthdr.rcvif = NULL; 669 #ifdef MAC 670 if (inp != NULL) { 671 /* 672 * Packet is associated with a socket, so allow the 673 * label of the response to reflect the socket label. 674 */ 675 INP_WLOCK_ASSERT(inp); 676 mac_inpcb_create_mbuf(inp, m); 677 } else { 678 /* 679 * Packet is not associated with a socket, so possibly 680 * update the label in place. 681 */ 682 mac_netinet_tcp_reply(m); 683 } 684 #endif 685 nth->th_seq = htonl(seq); 686 nth->th_ack = htonl(ack); 687 nth->th_x2 = 0; 688 nth->th_off = sizeof (struct tcphdr) >> 2; 689 nth->th_flags = flags; 690 if (tp != NULL) 691 nth->th_win = htons((u_short) (win >> tp->rcv_scale)); 692 else 693 nth->th_win = htons((u_short)win); 694 nth->th_urp = 0; 695 696 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); 697 #ifdef INET6 698 if (isipv6) { 699 m->m_pkthdr.csum_flags = CSUM_TCP_IPV6; 700 nth->th_sum = in6_cksum_pseudo(ip6, 701 tlen - sizeof(struct ip6_hdr), IPPROTO_TCP, 0); 702 ip6->ip6_hlim = in6_selecthlim(tp != NULL ? tp->t_inpcb : 703 NULL, NULL); 704 } 705 #endif /* INET6 */ 706 #if defined(INET6) && defined(INET) 707 else 708 #endif 709 #ifdef INET 710 { 711 m->m_pkthdr.csum_flags = CSUM_TCP; 712 nth->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, 713 htons((u_short)(tlen - sizeof(struct ip) + ip->ip_p))); 714 } 715 #endif /* INET */ 716 #ifdef TCPDEBUG 717 if (tp == NULL || (inp->inp_socket->so_options & SO_DEBUG)) 718 tcp_trace(TA_OUTPUT, 0, tp, mtod(m, void *), th, 0); 719 #endif 720 if (flags & TH_RST) 721 TCP_PROBE5(accept__refused, NULL, NULL, mtod(m, const char *), 722 tp, nth); 723 724 TCP_PROBE5(send, NULL, tp, mtod(m, const char *), tp, nth); 725 #ifdef INET6 726 if (isipv6) 727 (void) ip6_output(m, NULL, NULL, ipflags, NULL, NULL, inp); 728 #endif /* INET6 */ 729 #if defined(INET) && defined(INET6) 730 else 731 #endif 732 #ifdef INET 733 (void) ip_output(m, NULL, NULL, ipflags, NULL, inp); 734 #endif 735 } 736 737 /* 738 * Create a new TCP control block, making an 739 * empty reassembly queue and hooking it to the argument 740 * protocol control block. The `inp' parameter must have 741 * come from the zone allocator set up in tcp_init(). 742 */ 743 struct tcpcb * 744 tcp_newtcpcb(struct inpcb *inp) 745 { 746 struct tcpcb_mem *tm; 747 struct tcpcb *tp; 748 #ifdef INET6 749 int isipv6 = (inp->inp_vflag & INP_IPV6) != 0; 750 #endif /* INET6 */ 751 752 tm = uma_zalloc(V_tcpcb_zone, M_NOWAIT | M_ZERO); 753 if (tm == NULL) 754 return (NULL); 755 tp = &tm->tcb; 756 757 /* Initialise cc_var struct for this tcpcb. */ 758 tp->ccv = &tm->ccv; 759 tp->ccv->type = IPPROTO_TCP; 760 tp->ccv->ccvc.tcp = tp; 761 762 /* 763 * Use the current system default CC algorithm. 764 */ 765 CC_LIST_RLOCK(); 766 KASSERT(!STAILQ_EMPTY(&cc_list), ("cc_list is empty!")); 767 CC_ALGO(tp) = CC_DEFAULT(); 768 CC_LIST_RUNLOCK(); 769 770 if (CC_ALGO(tp)->cb_init != NULL) 771 if (CC_ALGO(tp)->cb_init(tp->ccv) > 0) { 772 uma_zfree(V_tcpcb_zone, tm); 773 return (NULL); 774 } 775 776 tp->osd = &tm->osd; 777 if (khelp_init_osd(HELPER_CLASS_TCP, tp->osd)) { 778 uma_zfree(V_tcpcb_zone, tm); 779 return (NULL); 780 } 781 782 #ifdef VIMAGE 783 tp->t_vnet = inp->inp_vnet; 784 #endif 785 tp->t_timers = &tm->tt; 786 /* LIST_INIT(&tp->t_segq); */ /* XXX covered by M_ZERO */ 787 tp->t_maxseg = tp->t_maxopd = 788 #ifdef INET6 789 isipv6 ? V_tcp_v6mssdflt : 790 #endif /* INET6 */ 791 V_tcp_mssdflt; 792 793 /* Set up our timeouts. */ 794 callout_init(&tp->t_timers->tt_rexmt, CALLOUT_MPSAFE); 795 callout_init(&tp->t_timers->tt_persist, CALLOUT_MPSAFE); 796 callout_init(&tp->t_timers->tt_keep, CALLOUT_MPSAFE); 797 callout_init(&tp->t_timers->tt_2msl, CALLOUT_MPSAFE); 798 callout_init(&tp->t_timers->tt_delack, CALLOUT_MPSAFE); 799 800 if (V_tcp_do_rfc1323) 801 tp->t_flags = (TF_REQ_SCALE|TF_REQ_TSTMP); 802 if (V_tcp_do_sack) 803 tp->t_flags |= TF_SACK_PERMIT; 804 TAILQ_INIT(&tp->snd_holes); 805 tp->t_inpcb = inp; /* XXX */ 806 /* 807 * Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no 808 * rtt estimate. Set rttvar so that srtt + 4 * rttvar gives 809 * reasonable initial retransmit time. 810 */ 811 tp->t_srtt = TCPTV_SRTTBASE; 812 tp->t_rttvar = ((TCPTV_RTOBASE - TCPTV_SRTTBASE) << TCP_RTTVAR_SHIFT) / 4; 813 tp->t_rttmin = tcp_rexmit_min; 814 tp->t_rxtcur = TCPTV_RTOBASE; 815 tp->snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT; 816 tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT; 817 tp->t_rcvtime = ticks; 818 /* 819 * IPv4 TTL initialization is necessary for an IPv6 socket as well, 820 * because the socket may be bound to an IPv6 wildcard address, 821 * which may match an IPv4-mapped IPv6 address. 822 */ 823 inp->inp_ip_ttl = V_ip_defttl; 824 inp->inp_ppcb = tp; 825 return (tp); /* XXX */ 826 } 827 828 /* 829 * Switch the congestion control algorithm back to NewReno for any active 830 * control blocks using an algorithm which is about to go away. 831 * This ensures the CC framework can allow the unload to proceed without leaving 832 * any dangling pointers which would trigger a panic. 833 * Returning non-zero would inform the CC framework that something went wrong 834 * and it would be unsafe to allow the unload to proceed. However, there is no 835 * way for this to occur with this implementation so we always return zero. 836 */ 837 int 838 tcp_ccalgounload(struct cc_algo *unload_algo) 839 { 840 struct cc_algo *tmpalgo; 841 struct inpcb *inp; 842 struct tcpcb *tp; 843 VNET_ITERATOR_DECL(vnet_iter); 844 845 /* 846 * Check all active control blocks across all network stacks and change 847 * any that are using "unload_algo" back to NewReno. If "unload_algo" 848 * requires cleanup code to be run, call it. 849 */ 850 VNET_LIST_RLOCK(); 851 VNET_FOREACH(vnet_iter) { 852 CURVNET_SET(vnet_iter); 853 INP_INFO_RLOCK(&V_tcbinfo); 854 /* 855 * New connections already part way through being initialised 856 * with the CC algo we're removing will not race with this code 857 * because the INP_INFO_WLOCK is held during initialisation. We 858 * therefore don't enter the loop below until the connection 859 * list has stabilised. 860 */ 861 LIST_FOREACH(inp, &V_tcb, inp_list) { 862 INP_WLOCK(inp); 863 /* Important to skip tcptw structs. */ 864 if (!(inp->inp_flags & INP_TIMEWAIT) && 865 (tp = intotcpcb(inp)) != NULL) { 866 /* 867 * By holding INP_WLOCK here, we are assured 868 * that the connection is not currently 869 * executing inside the CC module's functions 870 * i.e. it is safe to make the switch back to 871 * NewReno. 872 */ 873 if (CC_ALGO(tp) == unload_algo) { 874 tmpalgo = CC_ALGO(tp); 875 /* NewReno does not require any init. */ 876 CC_ALGO(tp) = &newreno_cc_algo; 877 if (tmpalgo->cb_destroy != NULL) 878 tmpalgo->cb_destroy(tp->ccv); 879 } 880 } 881 INP_WUNLOCK(inp); 882 } 883 INP_INFO_RUNLOCK(&V_tcbinfo); 884 CURVNET_RESTORE(); 885 } 886 VNET_LIST_RUNLOCK(); 887 888 return (0); 889 } 890 891 /* 892 * Drop a TCP connection, reporting 893 * the specified error. If connection is synchronized, 894 * then send a RST to peer. 895 */ 896 struct tcpcb * 897 tcp_drop(struct tcpcb *tp, int errno) 898 { 899 struct socket *so = tp->t_inpcb->inp_socket; 900 901 INP_INFO_WLOCK_ASSERT(&V_tcbinfo); 902 INP_WLOCK_ASSERT(tp->t_inpcb); 903 904 if (TCPS_HAVERCVDSYN(tp->t_state)) { 905 tcp_state_change(tp, TCPS_CLOSED); 906 (void) tcp_output(tp); 907 TCPSTAT_INC(tcps_drops); 908 } else 909 TCPSTAT_INC(tcps_conndrops); 910 if (errno == ETIMEDOUT && tp->t_softerror) 911 errno = tp->t_softerror; 912 so->so_error = errno; 913 return (tcp_close(tp)); 914 } 915 916 void 917 tcp_discardcb(struct tcpcb *tp) 918 { 919 struct inpcb *inp = tp->t_inpcb; 920 struct socket *so = inp->inp_socket; 921 #ifdef INET6 922 int isipv6 = (inp->inp_vflag & INP_IPV6) != 0; 923 #endif /* INET6 */ 924 925 INP_WLOCK_ASSERT(inp); 926 927 /* 928 * Make sure that all of our timers are stopped before we delete the 929 * PCB. 930 * 931 * XXXRW: Really, we would like to use callout_drain() here in order 932 * to avoid races experienced in tcp_timer.c where a timer is already 933 * executing at this point. However, we can't, both because we're 934 * running in a context where we can't sleep, and also because we 935 * hold locks required by the timers. What we instead need to do is 936 * test to see if callout_drain() is required, and if so, defer some 937 * portion of the remainder of tcp_discardcb() to an asynchronous 938 * context that can callout_drain() and then continue. Some care 939 * will be required to ensure that no further processing takes place 940 * on the tcpcb, even though it hasn't been freed (a flag?). 941 */ 942 callout_stop(&tp->t_timers->tt_rexmt); 943 callout_stop(&tp->t_timers->tt_persist); 944 callout_stop(&tp->t_timers->tt_keep); 945 callout_stop(&tp->t_timers->tt_2msl); 946 callout_stop(&tp->t_timers->tt_delack); 947 948 /* 949 * If we got enough samples through the srtt filter, 950 * save the rtt and rttvar in the routing entry. 951 * 'Enough' is arbitrarily defined as 4 rtt samples. 952 * 4 samples is enough for the srtt filter to converge 953 * to within enough % of the correct value; fewer samples 954 * and we could save a bogus rtt. The danger is not high 955 * as tcp quickly recovers from everything. 956 * XXX: Works very well but needs some more statistics! 957 */ 958 if (tp->t_rttupdated >= 4) { 959 struct hc_metrics_lite metrics; 960 u_long ssthresh; 961 962 bzero(&metrics, sizeof(metrics)); 963 /* 964 * Update the ssthresh always when the conditions below 965 * are satisfied. This gives us better new start value 966 * for the congestion avoidance for new connections. 967 * ssthresh is only set if packet loss occured on a session. 968 * 969 * XXXRW: 'so' may be NULL here, and/or socket buffer may be 970 * being torn down. Ideally this code would not use 'so'. 971 */ 972 ssthresh = tp->snd_ssthresh; 973 if (ssthresh != 0 && ssthresh < so->so_snd.sb_hiwat / 2) { 974 /* 975 * convert the limit from user data bytes to 976 * packets then to packet data bytes. 977 */ 978 ssthresh = (ssthresh + tp->t_maxseg / 2) / tp->t_maxseg; 979 if (ssthresh < 2) 980 ssthresh = 2; 981 ssthresh *= (u_long)(tp->t_maxseg + 982 #ifdef INET6 983 (isipv6 ? sizeof (struct ip6_hdr) + 984 sizeof (struct tcphdr) : 985 #endif 986 sizeof (struct tcpiphdr) 987 #ifdef INET6 988 ) 989 #endif 990 ); 991 } else 992 ssthresh = 0; 993 metrics.rmx_ssthresh = ssthresh; 994 995 metrics.rmx_rtt = tp->t_srtt; 996 metrics.rmx_rttvar = tp->t_rttvar; 997 metrics.rmx_cwnd = tp->snd_cwnd; 998 metrics.rmx_sendpipe = 0; 999 metrics.rmx_recvpipe = 0; 1000 1001 tcp_hc_update(&inp->inp_inc, &metrics); 1002 } 1003 1004 /* free the reassembly queue, if any */ 1005 tcp_reass_flush(tp); 1006 1007 #ifdef TCP_OFFLOAD 1008 /* Disconnect offload device, if any. */ 1009 if (tp->t_flags & TF_TOE) 1010 tcp_offload_detach(tp); 1011 #endif 1012 1013 tcp_free_sackholes(tp); 1014 1015 /* Allow the CC algorithm to clean up after itself. */ 1016 if (CC_ALGO(tp)->cb_destroy != NULL) 1017 CC_ALGO(tp)->cb_destroy(tp->ccv); 1018 1019 khelp_destroy_osd(tp->osd); 1020 1021 CC_ALGO(tp) = NULL; 1022 inp->inp_ppcb = NULL; 1023 tp->t_inpcb = NULL; 1024 uma_zfree(V_tcpcb_zone, tp); 1025 } 1026 1027 /* 1028 * Attempt to close a TCP control block, marking it as dropped, and freeing 1029 * the socket if we hold the only reference. 1030 */ 1031 struct tcpcb * 1032 tcp_close(struct tcpcb *tp) 1033 { 1034 struct inpcb *inp = tp->t_inpcb; 1035 struct socket *so; 1036 1037 INP_INFO_WLOCK_ASSERT(&V_tcbinfo); 1038 INP_WLOCK_ASSERT(inp); 1039 1040 #ifdef TCP_OFFLOAD 1041 if (tp->t_state == TCPS_LISTEN) 1042 tcp_offload_listen_stop(tp); 1043 #endif 1044 in_pcbdrop(inp); 1045 TCPSTAT_INC(tcps_closed); 1046 KASSERT(inp->inp_socket != NULL, ("tcp_close: inp_socket NULL")); 1047 so = inp->inp_socket; 1048 soisdisconnected(so); 1049 if (inp->inp_flags & INP_SOCKREF) { 1050 KASSERT(so->so_state & SS_PROTOREF, 1051 ("tcp_close: !SS_PROTOREF")); 1052 inp->inp_flags &= ~INP_SOCKREF; 1053 INP_WUNLOCK(inp); 1054 ACCEPT_LOCK(); 1055 SOCK_LOCK(so); 1056 so->so_state &= ~SS_PROTOREF; 1057 sofree(so); 1058 return (NULL); 1059 } 1060 return (tp); 1061 } 1062 1063 void 1064 tcp_drain(void) 1065 { 1066 VNET_ITERATOR_DECL(vnet_iter); 1067 1068 if (!do_tcpdrain) 1069 return; 1070 1071 VNET_LIST_RLOCK_NOSLEEP(); 1072 VNET_FOREACH(vnet_iter) { 1073 CURVNET_SET(vnet_iter); 1074 struct inpcb *inpb; 1075 struct tcpcb *tcpb; 1076 1077 /* 1078 * Walk the tcpbs, if existing, and flush the reassembly queue, 1079 * if there is one... 1080 * XXX: The "Net/3" implementation doesn't imply that the TCP 1081 * reassembly queue should be flushed, but in a situation 1082 * where we're really low on mbufs, this is potentially 1083 * useful. 1084 */ 1085 INP_INFO_RLOCK(&V_tcbinfo); 1086 LIST_FOREACH(inpb, V_tcbinfo.ipi_listhead, inp_list) { 1087 if (inpb->inp_flags & INP_TIMEWAIT) 1088 continue; 1089 INP_WLOCK(inpb); 1090 if ((tcpb = intotcpcb(inpb)) != NULL) { 1091 tcp_reass_flush(tcpb); 1092 tcp_clean_sackreport(tcpb); 1093 } 1094 INP_WUNLOCK(inpb); 1095 } 1096 INP_INFO_RUNLOCK(&V_tcbinfo); 1097 CURVNET_RESTORE(); 1098 } 1099 VNET_LIST_RUNLOCK_NOSLEEP(); 1100 } 1101 1102 /* 1103 * Notify a tcp user of an asynchronous error; 1104 * store error as soft error, but wake up user 1105 * (for now, won't do anything until can select for soft error). 1106 * 1107 * Do not wake up user since there currently is no mechanism for 1108 * reporting soft errors (yet - a kqueue filter may be added). 1109 */ 1110 static struct inpcb * 1111 tcp_notify(struct inpcb *inp, int error) 1112 { 1113 struct tcpcb *tp; 1114 1115 INP_INFO_WLOCK_ASSERT(&V_tcbinfo); 1116 INP_WLOCK_ASSERT(inp); 1117 1118 if ((inp->inp_flags & INP_TIMEWAIT) || 1119 (inp->inp_flags & INP_DROPPED)) 1120 return (inp); 1121 1122 tp = intotcpcb(inp); 1123 KASSERT(tp != NULL, ("tcp_notify: tp == NULL")); 1124 1125 /* 1126 * Ignore some errors if we are hooked up. 1127 * If connection hasn't completed, has retransmitted several times, 1128 * and receives a second error, give up now. This is better 1129 * than waiting a long time to establish a connection that 1130 * can never complete. 1131 */ 1132 if (tp->t_state == TCPS_ESTABLISHED && 1133 (error == EHOSTUNREACH || error == ENETUNREACH || 1134 error == EHOSTDOWN)) { 1135 return (inp); 1136 } else if (tp->t_state < TCPS_ESTABLISHED && tp->t_rxtshift > 3 && 1137 tp->t_softerror) { 1138 tp = tcp_drop(tp, error); 1139 if (tp != NULL) 1140 return (inp); 1141 else 1142 return (NULL); 1143 } else { 1144 tp->t_softerror = error; 1145 return (inp); 1146 } 1147 #if 0 1148 wakeup( &so->so_timeo); 1149 sorwakeup(so); 1150 sowwakeup(so); 1151 #endif 1152 } 1153 1154 static int 1155 tcp_pcblist(SYSCTL_HANDLER_ARGS) 1156 { 1157 int error, i, m, n, pcb_count; 1158 struct inpcb *inp, **inp_list; 1159 inp_gen_t gencnt; 1160 struct xinpgen xig; 1161 1162 /* 1163 * The process of preparing the TCB list is too time-consuming and 1164 * resource-intensive to repeat twice on every request. 1165 */ 1166 if (req->oldptr == NULL) { 1167 n = V_tcbinfo.ipi_count + syncache_pcbcount(); 1168 n += imax(n / 8, 10); 1169 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xtcpcb); 1170 return (0); 1171 } 1172 1173 if (req->newptr != NULL) 1174 return (EPERM); 1175 1176 /* 1177 * OK, now we're committed to doing something. 1178 */ 1179 INP_INFO_RLOCK(&V_tcbinfo); 1180 gencnt = V_tcbinfo.ipi_gencnt; 1181 n = V_tcbinfo.ipi_count; 1182 INP_INFO_RUNLOCK(&V_tcbinfo); 1183 1184 m = syncache_pcbcount(); 1185 1186 error = sysctl_wire_old_buffer(req, 2 * (sizeof xig) 1187 + (n + m) * sizeof(struct xtcpcb)); 1188 if (error != 0) 1189 return (error); 1190 1191 xig.xig_len = sizeof xig; 1192 xig.xig_count = n + m; 1193 xig.xig_gen = gencnt; 1194 xig.xig_sogen = so_gencnt; 1195 error = SYSCTL_OUT(req, &xig, sizeof xig); 1196 if (error) 1197 return (error); 1198 1199 error = syncache_pcblist(req, m, &pcb_count); 1200 if (error) 1201 return (error); 1202 1203 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK); 1204 if (inp_list == NULL) 1205 return (ENOMEM); 1206 1207 INP_INFO_RLOCK(&V_tcbinfo); 1208 for (inp = LIST_FIRST(V_tcbinfo.ipi_listhead), i = 0; 1209 inp != NULL && i < n; inp = LIST_NEXT(inp, inp_list)) { 1210 INP_WLOCK(inp); 1211 if (inp->inp_gencnt <= gencnt) { 1212 /* 1213 * XXX: This use of cr_cansee(), introduced with 1214 * TCP state changes, is not quite right, but for 1215 * now, better than nothing. 1216 */ 1217 if (inp->inp_flags & INP_TIMEWAIT) { 1218 if (intotw(inp) != NULL) 1219 error = cr_cansee(req->td->td_ucred, 1220 intotw(inp)->tw_cred); 1221 else 1222 error = EINVAL; /* Skip this inp. */ 1223 } else 1224 error = cr_canseeinpcb(req->td->td_ucred, inp); 1225 if (error == 0) { 1226 in_pcbref(inp); 1227 inp_list[i++] = inp; 1228 } 1229 } 1230 INP_WUNLOCK(inp); 1231 } 1232 INP_INFO_RUNLOCK(&V_tcbinfo); 1233 n = i; 1234 1235 error = 0; 1236 for (i = 0; i < n; i++) { 1237 inp = inp_list[i]; 1238 INP_RLOCK(inp); 1239 if (inp->inp_gencnt <= gencnt) { 1240 struct xtcpcb xt; 1241 void *inp_ppcb; 1242 1243 bzero(&xt, sizeof(xt)); 1244 xt.xt_len = sizeof xt; 1245 /* XXX should avoid extra copy */ 1246 bcopy(inp, &xt.xt_inp, sizeof *inp); 1247 inp_ppcb = inp->inp_ppcb; 1248 if (inp_ppcb == NULL) 1249 bzero((char *) &xt.xt_tp, sizeof xt.xt_tp); 1250 else if (inp->inp_flags & INP_TIMEWAIT) { 1251 bzero((char *) &xt.xt_tp, sizeof xt.xt_tp); 1252 xt.xt_tp.t_state = TCPS_TIME_WAIT; 1253 } else { 1254 bcopy(inp_ppcb, &xt.xt_tp, sizeof xt.xt_tp); 1255 if (xt.xt_tp.t_timers) 1256 tcp_timer_to_xtimer(&xt.xt_tp, xt.xt_tp.t_timers, &xt.xt_timer); 1257 } 1258 if (inp->inp_socket != NULL) 1259 sotoxsocket(inp->inp_socket, &xt.xt_socket); 1260 else { 1261 bzero(&xt.xt_socket, sizeof xt.xt_socket); 1262 xt.xt_socket.xso_protocol = IPPROTO_TCP; 1263 } 1264 xt.xt_inp.inp_gencnt = inp->inp_gencnt; 1265 INP_RUNLOCK(inp); 1266 error = SYSCTL_OUT(req, &xt, sizeof xt); 1267 } else 1268 INP_RUNLOCK(inp); 1269 } 1270 INP_INFO_WLOCK(&V_tcbinfo); 1271 for (i = 0; i < n; i++) { 1272 inp = inp_list[i]; 1273 INP_RLOCK(inp); 1274 if (!in_pcbrele_rlocked(inp)) 1275 INP_RUNLOCK(inp); 1276 } 1277 INP_INFO_WUNLOCK(&V_tcbinfo); 1278 1279 if (!error) { 1280 /* 1281 * Give the user an updated idea of our state. 1282 * If the generation differs from what we told 1283 * her before, she knows that something happened 1284 * while we were processing this request, and it 1285 * might be necessary to retry. 1286 */ 1287 INP_INFO_RLOCK(&V_tcbinfo); 1288 xig.xig_gen = V_tcbinfo.ipi_gencnt; 1289 xig.xig_sogen = so_gencnt; 1290 xig.xig_count = V_tcbinfo.ipi_count + pcb_count; 1291 INP_INFO_RUNLOCK(&V_tcbinfo); 1292 error = SYSCTL_OUT(req, &xig, sizeof xig); 1293 } 1294 free(inp_list, M_TEMP); 1295 return (error); 1296 } 1297 1298 SYSCTL_PROC(_net_inet_tcp, TCPCTL_PCBLIST, pcblist, 1299 CTLTYPE_OPAQUE | CTLFLAG_RD, NULL, 0, 1300 tcp_pcblist, "S,xtcpcb", "List of active TCP connections"); 1301 1302 #ifdef INET 1303 static int 1304 tcp_getcred(SYSCTL_HANDLER_ARGS) 1305 { 1306 struct xucred xuc; 1307 struct sockaddr_in addrs[2]; 1308 struct inpcb *inp; 1309 int error; 1310 1311 error = priv_check(req->td, PRIV_NETINET_GETCRED); 1312 if (error) 1313 return (error); 1314 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 1315 if (error) 1316 return (error); 1317 inp = in_pcblookup(&V_tcbinfo, addrs[1].sin_addr, addrs[1].sin_port, 1318 addrs[0].sin_addr, addrs[0].sin_port, INPLOOKUP_RLOCKPCB, NULL); 1319 if (inp != NULL) { 1320 if (inp->inp_socket == NULL) 1321 error = ENOENT; 1322 if (error == 0) 1323 error = cr_canseeinpcb(req->td->td_ucred, inp); 1324 if (error == 0) 1325 cru2x(inp->inp_cred, &xuc); 1326 INP_RUNLOCK(inp); 1327 } else 1328 error = ENOENT; 1329 if (error == 0) 1330 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 1331 return (error); 1332 } 1333 1334 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, getcred, 1335 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0, 1336 tcp_getcred, "S,xucred", "Get the xucred of a TCP connection"); 1337 #endif /* INET */ 1338 1339 #ifdef INET6 1340 static int 1341 tcp6_getcred(SYSCTL_HANDLER_ARGS) 1342 { 1343 struct xucred xuc; 1344 struct sockaddr_in6 addrs[2]; 1345 struct inpcb *inp; 1346 int error; 1347 #ifdef INET 1348 int mapped = 0; 1349 #endif 1350 1351 error = priv_check(req->td, PRIV_NETINET_GETCRED); 1352 if (error) 1353 return (error); 1354 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 1355 if (error) 1356 return (error); 1357 if ((error = sa6_embedscope(&addrs[0], V_ip6_use_defzone)) != 0 || 1358 (error = sa6_embedscope(&addrs[1], V_ip6_use_defzone)) != 0) { 1359 return (error); 1360 } 1361 if (IN6_IS_ADDR_V4MAPPED(&addrs[0].sin6_addr)) { 1362 #ifdef INET 1363 if (IN6_IS_ADDR_V4MAPPED(&addrs[1].sin6_addr)) 1364 mapped = 1; 1365 else 1366 #endif 1367 return (EINVAL); 1368 } 1369 1370 #ifdef INET 1371 if (mapped == 1) 1372 inp = in_pcblookup(&V_tcbinfo, 1373 *(struct in_addr *)&addrs[1].sin6_addr.s6_addr[12], 1374 addrs[1].sin6_port, 1375 *(struct in_addr *)&addrs[0].sin6_addr.s6_addr[12], 1376 addrs[0].sin6_port, INPLOOKUP_RLOCKPCB, NULL); 1377 else 1378 #endif 1379 inp = in6_pcblookup(&V_tcbinfo, 1380 &addrs[1].sin6_addr, addrs[1].sin6_port, 1381 &addrs[0].sin6_addr, addrs[0].sin6_port, 1382 INPLOOKUP_RLOCKPCB, NULL); 1383 if (inp != NULL) { 1384 if (inp->inp_socket == NULL) 1385 error = ENOENT; 1386 if (error == 0) 1387 error = cr_canseeinpcb(req->td->td_ucred, inp); 1388 if (error == 0) 1389 cru2x(inp->inp_cred, &xuc); 1390 INP_RUNLOCK(inp); 1391 } else 1392 error = ENOENT; 1393 if (error == 0) 1394 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 1395 return (error); 1396 } 1397 1398 SYSCTL_PROC(_net_inet6_tcp6, OID_AUTO, getcred, 1399 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0, 1400 tcp6_getcred, "S,xucred", "Get the xucred of a TCP6 connection"); 1401 #endif /* INET6 */ 1402 1403 1404 #ifdef INET 1405 void 1406 tcp_ctlinput(int cmd, struct sockaddr *sa, void *vip) 1407 { 1408 struct ip *ip = vip; 1409 struct tcphdr *th; 1410 struct in_addr faddr; 1411 struct inpcb *inp; 1412 struct tcpcb *tp; 1413 struct inpcb *(*notify)(struct inpcb *, int) = tcp_notify; 1414 struct icmp *icp; 1415 struct in_conninfo inc; 1416 tcp_seq icmp_tcp_seq; 1417 int mtu; 1418 1419 faddr = ((struct sockaddr_in *)sa)->sin_addr; 1420 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY) 1421 return; 1422 1423 if (cmd == PRC_MSGSIZE) 1424 notify = tcp_mtudisc_notify; 1425 else if (V_icmp_may_rst && (cmd == PRC_UNREACH_ADMIN_PROHIB || 1426 cmd == PRC_UNREACH_PORT || cmd == PRC_TIMXCEED_INTRANS) && ip) 1427 notify = tcp_drop_syn_sent; 1428 /* 1429 * Redirects don't need to be handled up here. 1430 */ 1431 else if (PRC_IS_REDIRECT(cmd)) 1432 return; 1433 /* 1434 * Source quench is depreciated. 1435 */ 1436 else if (cmd == PRC_QUENCH) 1437 return; 1438 /* 1439 * Hostdead is ugly because it goes linearly through all PCBs. 1440 * XXX: We never get this from ICMP, otherwise it makes an 1441 * excellent DoS attack on machines with many connections. 1442 */ 1443 else if (cmd == PRC_HOSTDEAD) 1444 ip = NULL; 1445 else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0) 1446 return; 1447 if (ip != NULL) { 1448 icp = (struct icmp *)((caddr_t)ip 1449 - offsetof(struct icmp, icmp_ip)); 1450 th = (struct tcphdr *)((caddr_t)ip 1451 + (ip->ip_hl << 2)); 1452 INP_INFO_WLOCK(&V_tcbinfo); 1453 inp = in_pcblookup(&V_tcbinfo, faddr, th->th_dport, 1454 ip->ip_src, th->th_sport, INPLOOKUP_WLOCKPCB, NULL); 1455 if (inp != NULL) { 1456 if (!(inp->inp_flags & INP_TIMEWAIT) && 1457 !(inp->inp_flags & INP_DROPPED) && 1458 !(inp->inp_socket == NULL)) { 1459 icmp_tcp_seq = htonl(th->th_seq); 1460 tp = intotcpcb(inp); 1461 if (SEQ_GEQ(icmp_tcp_seq, tp->snd_una) && 1462 SEQ_LT(icmp_tcp_seq, tp->snd_max)) { 1463 if (cmd == PRC_MSGSIZE) { 1464 /* 1465 * MTU discovery: 1466 * If we got a needfrag set the MTU 1467 * in the route to the suggested new 1468 * value (if given) and then notify. 1469 */ 1470 bzero(&inc, sizeof(inc)); 1471 inc.inc_faddr = faddr; 1472 inc.inc_fibnum = 1473 inp->inp_inc.inc_fibnum; 1474 1475 mtu = ntohs(icp->icmp_nextmtu); 1476 /* 1477 * If no alternative MTU was 1478 * proposed, try the next smaller 1479 * one. 1480 */ 1481 if (!mtu) 1482 mtu = ip_next_mtu( 1483 ntohs(ip->ip_len), 1); 1484 if (mtu < V_tcp_minmss 1485 + sizeof(struct tcpiphdr)) 1486 mtu = V_tcp_minmss 1487 + sizeof(struct tcpiphdr); 1488 /* 1489 * Only cache the MTU if it 1490 * is smaller than the interface 1491 * or route MTU. tcp_mtudisc() 1492 * will do right thing by itself. 1493 */ 1494 if (mtu <= tcp_maxmtu(&inc, NULL)) 1495 tcp_hc_updatemtu(&inc, mtu); 1496 tcp_mtudisc(inp, mtu); 1497 } else 1498 inp = (*notify)(inp, 1499 inetctlerrmap[cmd]); 1500 } 1501 } 1502 if (inp != NULL) 1503 INP_WUNLOCK(inp); 1504 } else { 1505 bzero(&inc, sizeof(inc)); 1506 inc.inc_fport = th->th_dport; 1507 inc.inc_lport = th->th_sport; 1508 inc.inc_faddr = faddr; 1509 inc.inc_laddr = ip->ip_src; 1510 syncache_unreach(&inc, th); 1511 } 1512 INP_INFO_WUNLOCK(&V_tcbinfo); 1513 } else 1514 in_pcbnotifyall(&V_tcbinfo, faddr, inetctlerrmap[cmd], notify); 1515 } 1516 #endif /* INET */ 1517 1518 #ifdef INET6 1519 void 1520 tcp6_ctlinput(int cmd, struct sockaddr *sa, void *d) 1521 { 1522 struct tcphdr th; 1523 struct inpcb *(*notify)(struct inpcb *, int) = tcp_notify; 1524 struct ip6_hdr *ip6; 1525 struct mbuf *m; 1526 struct ip6ctlparam *ip6cp = NULL; 1527 const struct sockaddr_in6 *sa6_src = NULL; 1528 int off; 1529 struct tcp_portonly { 1530 u_int16_t th_sport; 1531 u_int16_t th_dport; 1532 } *thp; 1533 1534 if (sa->sa_family != AF_INET6 || 1535 sa->sa_len != sizeof(struct sockaddr_in6)) 1536 return; 1537 1538 if (cmd == PRC_MSGSIZE) 1539 notify = tcp_mtudisc_notify; 1540 else if (!PRC_IS_REDIRECT(cmd) && 1541 ((unsigned)cmd >= PRC_NCMDS || inet6ctlerrmap[cmd] == 0)) 1542 return; 1543 /* Source quench is depreciated. */ 1544 else if (cmd == PRC_QUENCH) 1545 return; 1546 1547 /* if the parameter is from icmp6, decode it. */ 1548 if (d != NULL) { 1549 ip6cp = (struct ip6ctlparam *)d; 1550 m = ip6cp->ip6c_m; 1551 ip6 = ip6cp->ip6c_ip6; 1552 off = ip6cp->ip6c_off; 1553 sa6_src = ip6cp->ip6c_src; 1554 } else { 1555 m = NULL; 1556 ip6 = NULL; 1557 off = 0; /* fool gcc */ 1558 sa6_src = &sa6_any; 1559 } 1560 1561 if (ip6 != NULL) { 1562 struct in_conninfo inc; 1563 /* 1564 * XXX: We assume that when IPV6 is non NULL, 1565 * M and OFF are valid. 1566 */ 1567 1568 /* check if we can safely examine src and dst ports */ 1569 if (m->m_pkthdr.len < off + sizeof(*thp)) 1570 return; 1571 1572 bzero(&th, sizeof(th)); 1573 m_copydata(m, off, sizeof(*thp), (caddr_t)&th); 1574 1575 in6_pcbnotify(&V_tcbinfo, sa, th.th_dport, 1576 (struct sockaddr *)ip6cp->ip6c_src, 1577 th.th_sport, cmd, NULL, notify); 1578 1579 bzero(&inc, sizeof(inc)); 1580 inc.inc_fport = th.th_dport; 1581 inc.inc_lport = th.th_sport; 1582 inc.inc6_faddr = ((struct sockaddr_in6 *)sa)->sin6_addr; 1583 inc.inc6_laddr = ip6cp->ip6c_src->sin6_addr; 1584 inc.inc_flags |= INC_ISIPV6; 1585 INP_INFO_WLOCK(&V_tcbinfo); 1586 syncache_unreach(&inc, &th); 1587 INP_INFO_WUNLOCK(&V_tcbinfo); 1588 } else 1589 in6_pcbnotify(&V_tcbinfo, sa, 0, (const struct sockaddr *)sa6_src, 1590 0, cmd, NULL, notify); 1591 } 1592 #endif /* INET6 */ 1593 1594 1595 /* 1596 * Following is where TCP initial sequence number generation occurs. 1597 * 1598 * There are two places where we must use initial sequence numbers: 1599 * 1. In SYN-ACK packets. 1600 * 2. In SYN packets. 1601 * 1602 * All ISNs for SYN-ACK packets are generated by the syncache. See 1603 * tcp_syncache.c for details. 1604 * 1605 * The ISNs in SYN packets must be monotonic; TIME_WAIT recycling 1606 * depends on this property. In addition, these ISNs should be 1607 * unguessable so as to prevent connection hijacking. To satisfy 1608 * the requirements of this situation, the algorithm outlined in 1609 * RFC 1948 is used, with only small modifications. 1610 * 1611 * Implementation details: 1612 * 1613 * Time is based off the system timer, and is corrected so that it 1614 * increases by one megabyte per second. This allows for proper 1615 * recycling on high speed LANs while still leaving over an hour 1616 * before rollover. 1617 * 1618 * As reading the *exact* system time is too expensive to be done 1619 * whenever setting up a TCP connection, we increment the time 1620 * offset in two ways. First, a small random positive increment 1621 * is added to isn_offset for each connection that is set up. 1622 * Second, the function tcp_isn_tick fires once per clock tick 1623 * and increments isn_offset as necessary so that sequence numbers 1624 * are incremented at approximately ISN_BYTES_PER_SECOND. The 1625 * random positive increments serve only to ensure that the same 1626 * exact sequence number is never sent out twice (as could otherwise 1627 * happen when a port is recycled in less than the system tick 1628 * interval.) 1629 * 1630 * net.inet.tcp.isn_reseed_interval controls the number of seconds 1631 * between seeding of isn_secret. This is normally set to zero, 1632 * as reseeding should not be necessary. 1633 * 1634 * Locking of the global variables isn_secret, isn_last_reseed, isn_offset, 1635 * isn_offset_old, and isn_ctx is performed using the TCP pcbinfo lock. In 1636 * general, this means holding an exclusive (write) lock. 1637 */ 1638 1639 #define ISN_BYTES_PER_SECOND 1048576 1640 #define ISN_STATIC_INCREMENT 4096 1641 #define ISN_RANDOM_INCREMENT (4096 - 1) 1642 1643 static VNET_DEFINE(u_char, isn_secret[32]); 1644 static VNET_DEFINE(int, isn_last); 1645 static VNET_DEFINE(int, isn_last_reseed); 1646 static VNET_DEFINE(u_int32_t, isn_offset); 1647 static VNET_DEFINE(u_int32_t, isn_offset_old); 1648 1649 #define V_isn_secret VNET(isn_secret) 1650 #define V_isn_last VNET(isn_last) 1651 #define V_isn_last_reseed VNET(isn_last_reseed) 1652 #define V_isn_offset VNET(isn_offset) 1653 #define V_isn_offset_old VNET(isn_offset_old) 1654 1655 tcp_seq 1656 tcp_new_isn(struct tcpcb *tp) 1657 { 1658 MD5_CTX isn_ctx; 1659 u_int32_t md5_buffer[4]; 1660 tcp_seq new_isn; 1661 u_int32_t projected_offset; 1662 1663 INP_WLOCK_ASSERT(tp->t_inpcb); 1664 1665 ISN_LOCK(); 1666 /* Seed if this is the first use, reseed if requested. */ 1667 if ((V_isn_last_reseed == 0) || ((V_tcp_isn_reseed_interval > 0) && 1668 (((u_int)V_isn_last_reseed + (u_int)V_tcp_isn_reseed_interval*hz) 1669 < (u_int)ticks))) { 1670 read_random(&V_isn_secret, sizeof(V_isn_secret)); 1671 V_isn_last_reseed = ticks; 1672 } 1673 1674 /* Compute the md5 hash and return the ISN. */ 1675 MD5Init(&isn_ctx); 1676 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_fport, sizeof(u_short)); 1677 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_lport, sizeof(u_short)); 1678 #ifdef INET6 1679 if ((tp->t_inpcb->inp_vflag & INP_IPV6) != 0) { 1680 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->in6p_faddr, 1681 sizeof(struct in6_addr)); 1682 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->in6p_laddr, 1683 sizeof(struct in6_addr)); 1684 } else 1685 #endif 1686 { 1687 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_faddr, 1688 sizeof(struct in_addr)); 1689 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_laddr, 1690 sizeof(struct in_addr)); 1691 } 1692 MD5Update(&isn_ctx, (u_char *) &V_isn_secret, sizeof(V_isn_secret)); 1693 MD5Final((u_char *) &md5_buffer, &isn_ctx); 1694 new_isn = (tcp_seq) md5_buffer[0]; 1695 V_isn_offset += ISN_STATIC_INCREMENT + 1696 (arc4random() & ISN_RANDOM_INCREMENT); 1697 if (ticks != V_isn_last) { 1698 projected_offset = V_isn_offset_old + 1699 ISN_BYTES_PER_SECOND / hz * (ticks - V_isn_last); 1700 if (SEQ_GT(projected_offset, V_isn_offset)) 1701 V_isn_offset = projected_offset; 1702 V_isn_offset_old = V_isn_offset; 1703 V_isn_last = ticks; 1704 } 1705 new_isn += V_isn_offset; 1706 ISN_UNLOCK(); 1707 return (new_isn); 1708 } 1709 1710 /* 1711 * When a specific ICMP unreachable message is received and the 1712 * connection state is SYN-SENT, drop the connection. This behavior 1713 * is controlled by the icmp_may_rst sysctl. 1714 */ 1715 struct inpcb * 1716 tcp_drop_syn_sent(struct inpcb *inp, int errno) 1717 { 1718 struct tcpcb *tp; 1719 1720 INP_INFO_WLOCK_ASSERT(&V_tcbinfo); 1721 INP_WLOCK_ASSERT(inp); 1722 1723 if ((inp->inp_flags & INP_TIMEWAIT) || 1724 (inp->inp_flags & INP_DROPPED)) 1725 return (inp); 1726 1727 tp = intotcpcb(inp); 1728 if (tp->t_state != TCPS_SYN_SENT) 1729 return (inp); 1730 1731 tp = tcp_drop(tp, errno); 1732 if (tp != NULL) 1733 return (inp); 1734 else 1735 return (NULL); 1736 } 1737 1738 /* 1739 * When `need fragmentation' ICMP is received, update our idea of the MSS 1740 * based on the new value. Also nudge TCP to send something, since we 1741 * know the packet we just sent was dropped. 1742 * This duplicates some code in the tcp_mss() function in tcp_input.c. 1743 */ 1744 static struct inpcb * 1745 tcp_mtudisc_notify(struct inpcb *inp, int error) 1746 { 1747 1748 return (tcp_mtudisc(inp, -1)); 1749 } 1750 1751 struct inpcb * 1752 tcp_mtudisc(struct inpcb *inp, int mtuoffer) 1753 { 1754 struct tcpcb *tp; 1755 struct socket *so; 1756 1757 INP_WLOCK_ASSERT(inp); 1758 if ((inp->inp_flags & INP_TIMEWAIT) || 1759 (inp->inp_flags & INP_DROPPED)) 1760 return (inp); 1761 1762 tp = intotcpcb(inp); 1763 KASSERT(tp != NULL, ("tcp_mtudisc: tp == NULL")); 1764 1765 tcp_mss_update(tp, -1, mtuoffer, NULL, NULL); 1766 1767 so = inp->inp_socket; 1768 SOCKBUF_LOCK(&so->so_snd); 1769 /* If the mss is larger than the socket buffer, decrease the mss. */ 1770 if (so->so_snd.sb_hiwat < tp->t_maxseg) 1771 tp->t_maxseg = so->so_snd.sb_hiwat; 1772 SOCKBUF_UNLOCK(&so->so_snd); 1773 1774 TCPSTAT_INC(tcps_mturesent); 1775 tp->t_rtttime = 0; 1776 tp->snd_nxt = tp->snd_una; 1777 tcp_free_sackholes(tp); 1778 tp->snd_recover = tp->snd_max; 1779 if (tp->t_flags & TF_SACK_PERMIT) 1780 EXIT_FASTRECOVERY(tp->t_flags); 1781 tcp_output(tp); 1782 return (inp); 1783 } 1784 1785 #ifdef INET 1786 /* 1787 * Look-up the routing entry to the peer of this inpcb. If no route 1788 * is found and it cannot be allocated, then return 0. This routine 1789 * is called by TCP routines that access the rmx structure and by 1790 * tcp_mss_update to get the peer/interface MTU. 1791 */ 1792 u_long 1793 tcp_maxmtu(struct in_conninfo *inc, struct tcp_ifcap *cap) 1794 { 1795 struct route sro; 1796 struct sockaddr_in *dst; 1797 struct ifnet *ifp; 1798 u_long maxmtu = 0; 1799 1800 KASSERT(inc != NULL, ("tcp_maxmtu with NULL in_conninfo pointer")); 1801 1802 bzero(&sro, sizeof(sro)); 1803 if (inc->inc_faddr.s_addr != INADDR_ANY) { 1804 dst = (struct sockaddr_in *)&sro.ro_dst; 1805 dst->sin_family = AF_INET; 1806 dst->sin_len = sizeof(*dst); 1807 dst->sin_addr = inc->inc_faddr; 1808 in_rtalloc_ign(&sro, 0, inc->inc_fibnum); 1809 } 1810 if (sro.ro_rt != NULL) { 1811 ifp = sro.ro_rt->rt_ifp; 1812 if (sro.ro_rt->rt_mtu == 0) 1813 maxmtu = ifp->if_mtu; 1814 else 1815 maxmtu = min(sro.ro_rt->rt_mtu, ifp->if_mtu); 1816 1817 /* Report additional interface capabilities. */ 1818 if (cap != NULL) { 1819 if (ifp->if_capenable & IFCAP_TSO4 && 1820 ifp->if_hwassist & CSUM_TSO) { 1821 cap->ifcap |= CSUM_TSO; 1822 cap->tsomax = ifp->if_hw_tsomax; 1823 } 1824 } 1825 RTFREE(sro.ro_rt); 1826 } 1827 return (maxmtu); 1828 } 1829 #endif /* INET */ 1830 1831 #ifdef INET6 1832 u_long 1833 tcp_maxmtu6(struct in_conninfo *inc, struct tcp_ifcap *cap) 1834 { 1835 struct route_in6 sro6; 1836 struct ifnet *ifp; 1837 u_long maxmtu = 0; 1838 1839 KASSERT(inc != NULL, ("tcp_maxmtu6 with NULL in_conninfo pointer")); 1840 1841 bzero(&sro6, sizeof(sro6)); 1842 if (!IN6_IS_ADDR_UNSPECIFIED(&inc->inc6_faddr)) { 1843 sro6.ro_dst.sin6_family = AF_INET6; 1844 sro6.ro_dst.sin6_len = sizeof(struct sockaddr_in6); 1845 sro6.ro_dst.sin6_addr = inc->inc6_faddr; 1846 in6_rtalloc_ign(&sro6, 0, inc->inc_fibnum); 1847 } 1848 if (sro6.ro_rt != NULL) { 1849 ifp = sro6.ro_rt->rt_ifp; 1850 if (sro6.ro_rt->rt_mtu == 0) 1851 maxmtu = IN6_LINKMTU(sro6.ro_rt->rt_ifp); 1852 else 1853 maxmtu = min(sro6.ro_rt->rt_mtu, 1854 IN6_LINKMTU(sro6.ro_rt->rt_ifp)); 1855 1856 /* Report additional interface capabilities. */ 1857 if (cap != NULL) { 1858 if (ifp->if_capenable & IFCAP_TSO6 && 1859 ifp->if_hwassist & CSUM_TSO) { 1860 cap->ifcap |= CSUM_TSO; 1861 cap->tsomax = ifp->if_hw_tsomax; 1862 } 1863 } 1864 RTFREE(sro6.ro_rt); 1865 } 1866 1867 return (maxmtu); 1868 } 1869 #endif /* INET6 */ 1870 1871 #ifdef IPSEC 1872 /* compute ESP/AH header size for TCP, including outer IP header. */ 1873 size_t 1874 ipsec_hdrsiz_tcp(struct tcpcb *tp) 1875 { 1876 struct inpcb *inp; 1877 struct mbuf *m; 1878 size_t hdrsiz; 1879 struct ip *ip; 1880 #ifdef INET6 1881 struct ip6_hdr *ip6; 1882 #endif 1883 struct tcphdr *th; 1884 1885 if ((tp == NULL) || ((inp = tp->t_inpcb) == NULL)) 1886 return (0); 1887 m = m_gethdr(M_NOWAIT, MT_DATA); 1888 if (!m) 1889 return (0); 1890 1891 #ifdef INET6 1892 if ((inp->inp_vflag & INP_IPV6) != 0) { 1893 ip6 = mtod(m, struct ip6_hdr *); 1894 th = (struct tcphdr *)(ip6 + 1); 1895 m->m_pkthdr.len = m->m_len = 1896 sizeof(struct ip6_hdr) + sizeof(struct tcphdr); 1897 tcpip_fillheaders(inp, ip6, th); 1898 hdrsiz = ipsec_hdrsiz(m, IPSEC_DIR_OUTBOUND, inp); 1899 } else 1900 #endif /* INET6 */ 1901 { 1902 ip = mtod(m, struct ip *); 1903 th = (struct tcphdr *)(ip + 1); 1904 m->m_pkthdr.len = m->m_len = sizeof(struct tcpiphdr); 1905 tcpip_fillheaders(inp, ip, th); 1906 hdrsiz = ipsec_hdrsiz(m, IPSEC_DIR_OUTBOUND, inp); 1907 } 1908 1909 m_free(m); 1910 return (hdrsiz); 1911 } 1912 #endif /* IPSEC */ 1913 1914 #ifdef TCP_SIGNATURE 1915 /* 1916 * Callback function invoked by m_apply() to digest TCP segment data 1917 * contained within an mbuf chain. 1918 */ 1919 static int 1920 tcp_signature_apply(void *fstate, void *data, u_int len) 1921 { 1922 1923 MD5Update(fstate, (u_char *)data, len); 1924 return (0); 1925 } 1926 1927 /* 1928 * Compute TCP-MD5 hash of a TCP segment. (RFC2385) 1929 * 1930 * Parameters: 1931 * m pointer to head of mbuf chain 1932 * _unused 1933 * len length of TCP segment data, excluding options 1934 * optlen length of TCP segment options 1935 * buf pointer to storage for computed MD5 digest 1936 * direction direction of flow (IPSEC_DIR_INBOUND or OUTBOUND) 1937 * 1938 * We do this over ip, tcphdr, segment data, and the key in the SADB. 1939 * When called from tcp_input(), we can be sure that th_sum has been 1940 * zeroed out and verified already. 1941 * 1942 * Return 0 if successful, otherwise return -1. 1943 * 1944 * XXX The key is retrieved from the system's PF_KEY SADB, by keying a 1945 * search with the destination IP address, and a 'magic SPI' to be 1946 * determined by the application. This is hardcoded elsewhere to 1179 1947 * right now. Another branch of this code exists which uses the SPD to 1948 * specify per-application flows but it is unstable. 1949 */ 1950 int 1951 tcp_signature_compute(struct mbuf *m, int _unused, int len, int optlen, 1952 u_char *buf, u_int direction) 1953 { 1954 union sockaddr_union dst; 1955 #ifdef INET 1956 struct ippseudo ippseudo; 1957 #endif 1958 MD5_CTX ctx; 1959 int doff; 1960 struct ip *ip; 1961 #ifdef INET 1962 struct ipovly *ipovly; 1963 #endif 1964 struct secasvar *sav; 1965 struct tcphdr *th; 1966 #ifdef INET6 1967 struct ip6_hdr *ip6; 1968 struct in6_addr in6; 1969 char ip6buf[INET6_ADDRSTRLEN]; 1970 uint32_t plen; 1971 uint16_t nhdr; 1972 #endif 1973 u_short savecsum; 1974 1975 KASSERT(m != NULL, ("NULL mbuf chain")); 1976 KASSERT(buf != NULL, ("NULL signature pointer")); 1977 1978 /* Extract the destination from the IP header in the mbuf. */ 1979 bzero(&dst, sizeof(union sockaddr_union)); 1980 ip = mtod(m, struct ip *); 1981 #ifdef INET6 1982 ip6 = NULL; /* Make the compiler happy. */ 1983 #endif 1984 switch (ip->ip_v) { 1985 #ifdef INET 1986 case IPVERSION: 1987 dst.sa.sa_len = sizeof(struct sockaddr_in); 1988 dst.sa.sa_family = AF_INET; 1989 dst.sin.sin_addr = (direction == IPSEC_DIR_INBOUND) ? 1990 ip->ip_src : ip->ip_dst; 1991 break; 1992 #endif 1993 #ifdef INET6 1994 case (IPV6_VERSION >> 4): 1995 ip6 = mtod(m, struct ip6_hdr *); 1996 dst.sa.sa_len = sizeof(struct sockaddr_in6); 1997 dst.sa.sa_family = AF_INET6; 1998 dst.sin6.sin6_addr = (direction == IPSEC_DIR_INBOUND) ? 1999 ip6->ip6_src : ip6->ip6_dst; 2000 break; 2001 #endif 2002 default: 2003 return (EINVAL); 2004 /* NOTREACHED */ 2005 break; 2006 } 2007 2008 /* Look up an SADB entry which matches the address of the peer. */ 2009 sav = KEY_ALLOCSA(&dst, IPPROTO_TCP, htonl(TCP_SIG_SPI)); 2010 if (sav == NULL) { 2011 ipseclog((LOG_ERR, "%s: SADB lookup failed for %s\n", __func__, 2012 (ip->ip_v == IPVERSION) ? inet_ntoa(dst.sin.sin_addr) : 2013 #ifdef INET6 2014 (ip->ip_v == (IPV6_VERSION >> 4)) ? 2015 ip6_sprintf(ip6buf, &dst.sin6.sin6_addr) : 2016 #endif 2017 "(unsupported)")); 2018 return (EINVAL); 2019 } 2020 2021 MD5Init(&ctx); 2022 /* 2023 * Step 1: Update MD5 hash with IP(v6) pseudo-header. 2024 * 2025 * XXX The ippseudo header MUST be digested in network byte order, 2026 * or else we'll fail the regression test. Assume all fields we've 2027 * been doing arithmetic on have been in host byte order. 2028 * XXX One cannot depend on ipovly->ih_len here. When called from 2029 * tcp_output(), the underlying ip_len member has not yet been set. 2030 */ 2031 switch (ip->ip_v) { 2032 #ifdef INET 2033 case IPVERSION: 2034 ipovly = (struct ipovly *)ip; 2035 ippseudo.ippseudo_src = ipovly->ih_src; 2036 ippseudo.ippseudo_dst = ipovly->ih_dst; 2037 ippseudo.ippseudo_pad = 0; 2038 ippseudo.ippseudo_p = IPPROTO_TCP; 2039 ippseudo.ippseudo_len = htons(len + sizeof(struct tcphdr) + 2040 optlen); 2041 MD5Update(&ctx, (char *)&ippseudo, sizeof(struct ippseudo)); 2042 2043 th = (struct tcphdr *)((u_char *)ip + sizeof(struct ip)); 2044 doff = sizeof(struct ip) + sizeof(struct tcphdr) + optlen; 2045 break; 2046 #endif 2047 #ifdef INET6 2048 /* 2049 * RFC 2385, 2.0 Proposal 2050 * For IPv6, the pseudo-header is as described in RFC 2460, namely the 2051 * 128-bit source IPv6 address, 128-bit destination IPv6 address, zero- 2052 * extended next header value (to form 32 bits), and 32-bit segment 2053 * length. 2054 * Note: Upper-Layer Packet Length comes before Next Header. 2055 */ 2056 case (IPV6_VERSION >> 4): 2057 in6 = ip6->ip6_src; 2058 in6_clearscope(&in6); 2059 MD5Update(&ctx, (char *)&in6, sizeof(struct in6_addr)); 2060 in6 = ip6->ip6_dst; 2061 in6_clearscope(&in6); 2062 MD5Update(&ctx, (char *)&in6, sizeof(struct in6_addr)); 2063 plen = htonl(len + sizeof(struct tcphdr) + optlen); 2064 MD5Update(&ctx, (char *)&plen, sizeof(uint32_t)); 2065 nhdr = 0; 2066 MD5Update(&ctx, (char *)&nhdr, sizeof(uint8_t)); 2067 MD5Update(&ctx, (char *)&nhdr, sizeof(uint8_t)); 2068 MD5Update(&ctx, (char *)&nhdr, sizeof(uint8_t)); 2069 nhdr = IPPROTO_TCP; 2070 MD5Update(&ctx, (char *)&nhdr, sizeof(uint8_t)); 2071 2072 th = (struct tcphdr *)((u_char *)ip6 + sizeof(struct ip6_hdr)); 2073 doff = sizeof(struct ip6_hdr) + sizeof(struct tcphdr) + optlen; 2074 break; 2075 #endif 2076 default: 2077 return (EINVAL); 2078 /* NOTREACHED */ 2079 break; 2080 } 2081 2082 2083 /* 2084 * Step 2: Update MD5 hash with TCP header, excluding options. 2085 * The TCP checksum must be set to zero. 2086 */ 2087 savecsum = th->th_sum; 2088 th->th_sum = 0; 2089 MD5Update(&ctx, (char *)th, sizeof(struct tcphdr)); 2090 th->th_sum = savecsum; 2091 2092 /* 2093 * Step 3: Update MD5 hash with TCP segment data. 2094 * Use m_apply() to avoid an early m_pullup(). 2095 */ 2096 if (len > 0) 2097 m_apply(m, doff, len, tcp_signature_apply, &ctx); 2098 2099 /* 2100 * Step 4: Update MD5 hash with shared secret. 2101 */ 2102 MD5Update(&ctx, sav->key_auth->key_data, _KEYLEN(sav->key_auth)); 2103 MD5Final(buf, &ctx); 2104 2105 key_sa_recordxfer(sav, m); 2106 KEY_FREESAV(&sav); 2107 return (0); 2108 } 2109 2110 /* 2111 * Verify the TCP-MD5 hash of a TCP segment. (RFC2385) 2112 * 2113 * Parameters: 2114 * m pointer to head of mbuf chain 2115 * len length of TCP segment data, excluding options 2116 * optlen length of TCP segment options 2117 * buf pointer to storage for computed MD5 digest 2118 * direction direction of flow (IPSEC_DIR_INBOUND or OUTBOUND) 2119 * 2120 * Return 1 if successful, otherwise return 0. 2121 */ 2122 int 2123 tcp_signature_verify(struct mbuf *m, int off0, int tlen, int optlen, 2124 struct tcpopt *to, struct tcphdr *th, u_int tcpbflag) 2125 { 2126 char tmpdigest[TCP_SIGLEN]; 2127 2128 if (tcp_sig_checksigs == 0) 2129 return (1); 2130 if ((tcpbflag & TF_SIGNATURE) == 0) { 2131 if ((to->to_flags & TOF_SIGNATURE) != 0) { 2132 2133 /* 2134 * If this socket is not expecting signature but 2135 * the segment contains signature just fail. 2136 */ 2137 TCPSTAT_INC(tcps_sig_err_sigopt); 2138 TCPSTAT_INC(tcps_sig_rcvbadsig); 2139 return (0); 2140 } 2141 2142 /* Signature is not expected, and not present in segment. */ 2143 return (1); 2144 } 2145 2146 /* 2147 * If this socket is expecting signature but the segment does not 2148 * contain any just fail. 2149 */ 2150 if ((to->to_flags & TOF_SIGNATURE) == 0) { 2151 TCPSTAT_INC(tcps_sig_err_nosigopt); 2152 TCPSTAT_INC(tcps_sig_rcvbadsig); 2153 return (0); 2154 } 2155 if (tcp_signature_compute(m, off0, tlen, optlen, &tmpdigest[0], 2156 IPSEC_DIR_INBOUND) == -1) { 2157 TCPSTAT_INC(tcps_sig_err_buildsig); 2158 TCPSTAT_INC(tcps_sig_rcvbadsig); 2159 return (0); 2160 } 2161 2162 if (bcmp(to->to_signature, &tmpdigest[0], TCP_SIGLEN) != 0) { 2163 TCPSTAT_INC(tcps_sig_rcvbadsig); 2164 return (0); 2165 } 2166 TCPSTAT_INC(tcps_sig_rcvgoodsig); 2167 return (1); 2168 } 2169 #endif /* TCP_SIGNATURE */ 2170 2171 static int 2172 sysctl_drop(SYSCTL_HANDLER_ARGS) 2173 { 2174 /* addrs[0] is a foreign socket, addrs[1] is a local one. */ 2175 struct sockaddr_storage addrs[2]; 2176 struct inpcb *inp; 2177 struct tcpcb *tp; 2178 struct tcptw *tw; 2179 struct sockaddr_in *fin, *lin; 2180 #ifdef INET6 2181 struct sockaddr_in6 *fin6, *lin6; 2182 #endif 2183 int error; 2184 2185 inp = NULL; 2186 fin = lin = NULL; 2187 #ifdef INET6 2188 fin6 = lin6 = NULL; 2189 #endif 2190 error = 0; 2191 2192 if (req->oldptr != NULL || req->oldlen != 0) 2193 return (EINVAL); 2194 if (req->newptr == NULL) 2195 return (EPERM); 2196 if (req->newlen < sizeof(addrs)) 2197 return (ENOMEM); 2198 error = SYSCTL_IN(req, &addrs, sizeof(addrs)); 2199 if (error) 2200 return (error); 2201 2202 switch (addrs[0].ss_family) { 2203 #ifdef INET6 2204 case AF_INET6: 2205 fin6 = (struct sockaddr_in6 *)&addrs[0]; 2206 lin6 = (struct sockaddr_in6 *)&addrs[1]; 2207 if (fin6->sin6_len != sizeof(struct sockaddr_in6) || 2208 lin6->sin6_len != sizeof(struct sockaddr_in6)) 2209 return (EINVAL); 2210 if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr)) { 2211 if (!IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr)) 2212 return (EINVAL); 2213 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[0]); 2214 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[1]); 2215 fin = (struct sockaddr_in *)&addrs[0]; 2216 lin = (struct sockaddr_in *)&addrs[1]; 2217 break; 2218 } 2219 error = sa6_embedscope(fin6, V_ip6_use_defzone); 2220 if (error) 2221 return (error); 2222 error = sa6_embedscope(lin6, V_ip6_use_defzone); 2223 if (error) 2224 return (error); 2225 break; 2226 #endif 2227 #ifdef INET 2228 case AF_INET: 2229 fin = (struct sockaddr_in *)&addrs[0]; 2230 lin = (struct sockaddr_in *)&addrs[1]; 2231 if (fin->sin_len != sizeof(struct sockaddr_in) || 2232 lin->sin_len != sizeof(struct sockaddr_in)) 2233 return (EINVAL); 2234 break; 2235 #endif 2236 default: 2237 return (EINVAL); 2238 } 2239 INP_INFO_WLOCK(&V_tcbinfo); 2240 switch (addrs[0].ss_family) { 2241 #ifdef INET6 2242 case AF_INET6: 2243 inp = in6_pcblookup(&V_tcbinfo, &fin6->sin6_addr, 2244 fin6->sin6_port, &lin6->sin6_addr, lin6->sin6_port, 2245 INPLOOKUP_WLOCKPCB, NULL); 2246 break; 2247 #endif 2248 #ifdef INET 2249 case AF_INET: 2250 inp = in_pcblookup(&V_tcbinfo, fin->sin_addr, fin->sin_port, 2251 lin->sin_addr, lin->sin_port, INPLOOKUP_WLOCKPCB, NULL); 2252 break; 2253 #endif 2254 } 2255 if (inp != NULL) { 2256 if (inp->inp_flags & INP_TIMEWAIT) { 2257 /* 2258 * XXXRW: There currently exists a state where an 2259 * inpcb is present, but its timewait state has been 2260 * discarded. For now, don't allow dropping of this 2261 * type of inpcb. 2262 */ 2263 tw = intotw(inp); 2264 if (tw != NULL) 2265 tcp_twclose(tw, 0); 2266 else 2267 INP_WUNLOCK(inp); 2268 } else if (!(inp->inp_flags & INP_DROPPED) && 2269 !(inp->inp_socket->so_options & SO_ACCEPTCONN)) { 2270 tp = intotcpcb(inp); 2271 tp = tcp_drop(tp, ECONNABORTED); 2272 if (tp != NULL) 2273 INP_WUNLOCK(inp); 2274 } else 2275 INP_WUNLOCK(inp); 2276 } else 2277 error = ESRCH; 2278 INP_INFO_WUNLOCK(&V_tcbinfo); 2279 return (error); 2280 } 2281 2282 SYSCTL_VNET_PROC(_net_inet_tcp, TCPCTL_DROP, drop, 2283 CTLTYPE_STRUCT|CTLFLAG_WR|CTLFLAG_SKIP, NULL, 2284 0, sysctl_drop, "", "Drop TCP connection"); 2285 2286 /* 2287 * Generate a standardized TCP log line for use throughout the 2288 * tcp subsystem. Memory allocation is done with M_NOWAIT to 2289 * allow use in the interrupt context. 2290 * 2291 * NB: The caller MUST free(s, M_TCPLOG) the returned string. 2292 * NB: The function may return NULL if memory allocation failed. 2293 * 2294 * Due to header inclusion and ordering limitations the struct ip 2295 * and ip6_hdr pointers have to be passed as void pointers. 2296 */ 2297 char * 2298 tcp_log_vain(struct in_conninfo *inc, struct tcphdr *th, void *ip4hdr, 2299 const void *ip6hdr) 2300 { 2301 2302 /* Is logging enabled? */ 2303 if (tcp_log_in_vain == 0) 2304 return (NULL); 2305 2306 return (tcp_log_addr(inc, th, ip4hdr, ip6hdr)); 2307 } 2308 2309 char * 2310 tcp_log_addrs(struct in_conninfo *inc, struct tcphdr *th, void *ip4hdr, 2311 const void *ip6hdr) 2312 { 2313 2314 /* Is logging enabled? */ 2315 if (tcp_log_debug == 0) 2316 return (NULL); 2317 2318 return (tcp_log_addr(inc, th, ip4hdr, ip6hdr)); 2319 } 2320 2321 static char * 2322 tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th, void *ip4hdr, 2323 const void *ip6hdr) 2324 { 2325 char *s, *sp; 2326 size_t size; 2327 struct ip *ip; 2328 #ifdef INET6 2329 const struct ip6_hdr *ip6; 2330 2331 ip6 = (const struct ip6_hdr *)ip6hdr; 2332 #endif /* INET6 */ 2333 ip = (struct ip *)ip4hdr; 2334 2335 /* 2336 * The log line looks like this: 2337 * "TCP: [1.2.3.4]:50332 to [1.2.3.4]:80 tcpflags 0x2<SYN>" 2338 */ 2339 size = sizeof("TCP: []:12345 to []:12345 tcpflags 0x2<>") + 2340 sizeof(PRINT_TH_FLAGS) + 1 + 2341 #ifdef INET6 2342 2 * INET6_ADDRSTRLEN; 2343 #else 2344 2 * INET_ADDRSTRLEN; 2345 #endif /* INET6 */ 2346 2347 s = malloc(size, M_TCPLOG, M_ZERO|M_NOWAIT); 2348 if (s == NULL) 2349 return (NULL); 2350 2351 strcat(s, "TCP: ["); 2352 sp = s + strlen(s); 2353 2354 if (inc && ((inc->inc_flags & INC_ISIPV6) == 0)) { 2355 inet_ntoa_r(inc->inc_faddr, sp); 2356 sp = s + strlen(s); 2357 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport)); 2358 sp = s + strlen(s); 2359 inet_ntoa_r(inc->inc_laddr, sp); 2360 sp = s + strlen(s); 2361 sprintf(sp, "]:%i", ntohs(inc->inc_lport)); 2362 #ifdef INET6 2363 } else if (inc) { 2364 ip6_sprintf(sp, &inc->inc6_faddr); 2365 sp = s + strlen(s); 2366 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport)); 2367 sp = s + strlen(s); 2368 ip6_sprintf(sp, &inc->inc6_laddr); 2369 sp = s + strlen(s); 2370 sprintf(sp, "]:%i", ntohs(inc->inc_lport)); 2371 } else if (ip6 && th) { 2372 ip6_sprintf(sp, &ip6->ip6_src); 2373 sp = s + strlen(s); 2374 sprintf(sp, "]:%i to [", ntohs(th->th_sport)); 2375 sp = s + strlen(s); 2376 ip6_sprintf(sp, &ip6->ip6_dst); 2377 sp = s + strlen(s); 2378 sprintf(sp, "]:%i", ntohs(th->th_dport)); 2379 #endif /* INET6 */ 2380 #ifdef INET 2381 } else if (ip && th) { 2382 inet_ntoa_r(ip->ip_src, sp); 2383 sp = s + strlen(s); 2384 sprintf(sp, "]:%i to [", ntohs(th->th_sport)); 2385 sp = s + strlen(s); 2386 inet_ntoa_r(ip->ip_dst, sp); 2387 sp = s + strlen(s); 2388 sprintf(sp, "]:%i", ntohs(th->th_dport)); 2389 #endif /* INET */ 2390 } else { 2391 free(s, M_TCPLOG); 2392 return (NULL); 2393 } 2394 sp = s + strlen(s); 2395 if (th) 2396 sprintf(sp, " tcpflags 0x%b", th->th_flags, PRINT_TH_FLAGS); 2397 if (*(s + size - 1) != '\0') 2398 panic("%s: string too long", __func__); 2399 return (s); 2400 } 2401 2402 /* 2403 * A subroutine which makes it easy to track TCP state changes with DTrace. 2404 * This function shouldn't be called for t_state initializations that don't 2405 * correspond to actual TCP state transitions. 2406 */ 2407 void 2408 tcp_state_change(struct tcpcb *tp, int newstate) 2409 { 2410 #if defined(KDTRACE_HOOKS) 2411 int pstate = tp->t_state; 2412 #endif 2413 2414 tp->t_state = newstate; 2415 TCP_PROBE6(state__change, NULL, tp, NULL, tp, NULL, pstate); 2416 } 2417