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 tcp_reass_init(); 379 380 TUNABLE_INT_FETCH("net.inet.tcp.sack.enable", &V_tcp_do_sack); 381 V_sack_hole_zone = uma_zcreate("sackhole", sizeof(struct sackhole), 382 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 383 384 /* Skip initialization of globals for non-default instances. */ 385 if (!IS_DEFAULT_VNET(curvnet)) 386 return; 387 388 /* XXX virtualize those bellow? */ 389 tcp_delacktime = TCPTV_DELACK; 390 tcp_keepinit = TCPTV_KEEP_INIT; 391 tcp_keepidle = TCPTV_KEEP_IDLE; 392 tcp_keepintvl = TCPTV_KEEPINTVL; 393 tcp_maxpersistidle = TCPTV_KEEP_IDLE; 394 tcp_msl = TCPTV_MSL; 395 tcp_rexmit_min = TCPTV_MIN; 396 if (tcp_rexmit_min < 1) 397 tcp_rexmit_min = 1; 398 tcp_rexmit_slop = TCPTV_CPU_VAR; 399 tcp_finwait2_timeout = TCPTV_FINWAIT2_TIMEOUT; 400 tcp_tcbhashsize = hashsize; 401 402 TUNABLE_INT_FETCH("net.inet.tcp.soreceive_stream", &tcp_soreceive_stream); 403 if (tcp_soreceive_stream) { 404 #ifdef INET 405 tcp_usrreqs.pru_soreceive = soreceive_stream; 406 #endif 407 #ifdef INET6 408 tcp6_usrreqs.pru_soreceive = soreceive_stream; 409 #endif /* INET6 */ 410 } 411 412 #ifdef INET6 413 #define TCP_MINPROTOHDR (sizeof(struct ip6_hdr) + sizeof(struct tcphdr)) 414 #else /* INET6 */ 415 #define TCP_MINPROTOHDR (sizeof(struct tcpiphdr)) 416 #endif /* INET6 */ 417 if (max_protohdr < TCP_MINPROTOHDR) 418 max_protohdr = TCP_MINPROTOHDR; 419 if (max_linkhdr + TCP_MINPROTOHDR > MHLEN) 420 panic("tcp_init"); 421 #undef TCP_MINPROTOHDR 422 423 ISN_LOCK_INIT(); 424 EVENTHANDLER_REGISTER(shutdown_pre_sync, tcp_fini, NULL, 425 SHUTDOWN_PRI_DEFAULT); 426 EVENTHANDLER_REGISTER(maxsockets_change, tcp_zone_change, NULL, 427 EVENTHANDLER_PRI_ANY); 428 } 429 430 #ifdef VIMAGE 431 void 432 tcp_destroy(void) 433 { 434 int error; 435 436 tcp_reass_destroy(); 437 tcp_hc_destroy(); 438 syncache_destroy(); 439 tcp_tw_destroy(); 440 in_pcbinfo_destroy(&V_tcbinfo); 441 uma_zdestroy(V_sack_hole_zone); 442 uma_zdestroy(V_tcpcb_zone); 443 444 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_IN]); 445 if (error != 0) { 446 printf("%s: WARNING: unable to deregister helper hook " 447 "type=%d, id=%d: error %d returned\n", __func__, 448 HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN, error); 449 } 450 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_OUT]); 451 if (error != 0) { 452 printf("%s: WARNING: unable to deregister helper hook " 453 "type=%d, id=%d: error %d returned\n", __func__, 454 HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT, error); 455 } 456 } 457 #endif 458 459 void 460 tcp_fini(void *xtp) 461 { 462 463 } 464 465 /* 466 * Fill in the IP and TCP headers for an outgoing packet, given the tcpcb. 467 * tcp_template used to store this data in mbufs, but we now recopy it out 468 * of the tcpcb each time to conserve mbufs. 469 */ 470 void 471 tcpip_fillheaders(struct inpcb *inp, void *ip_ptr, void *tcp_ptr) 472 { 473 struct tcphdr *th = (struct tcphdr *)tcp_ptr; 474 475 INP_WLOCK_ASSERT(inp); 476 477 #ifdef INET6 478 if ((inp->inp_vflag & INP_IPV6) != 0) { 479 struct ip6_hdr *ip6; 480 481 ip6 = (struct ip6_hdr *)ip_ptr; 482 ip6->ip6_flow = (ip6->ip6_flow & ~IPV6_FLOWINFO_MASK) | 483 (inp->inp_flow & IPV6_FLOWINFO_MASK); 484 ip6->ip6_vfc = (ip6->ip6_vfc & ~IPV6_VERSION_MASK) | 485 (IPV6_VERSION & IPV6_VERSION_MASK); 486 ip6->ip6_nxt = IPPROTO_TCP; 487 ip6->ip6_plen = htons(sizeof(struct tcphdr)); 488 ip6->ip6_src = inp->in6p_laddr; 489 ip6->ip6_dst = inp->in6p_faddr; 490 } 491 #endif /* INET6 */ 492 #if defined(INET6) && defined(INET) 493 else 494 #endif 495 #ifdef INET 496 { 497 struct ip *ip; 498 499 ip = (struct ip *)ip_ptr; 500 ip->ip_v = IPVERSION; 501 ip->ip_hl = 5; 502 ip->ip_tos = inp->inp_ip_tos; 503 ip->ip_len = 0; 504 ip->ip_id = 0; 505 ip->ip_off = 0; 506 ip->ip_ttl = inp->inp_ip_ttl; 507 ip->ip_sum = 0; 508 ip->ip_p = IPPROTO_TCP; 509 ip->ip_src = inp->inp_laddr; 510 ip->ip_dst = inp->inp_faddr; 511 } 512 #endif /* INET */ 513 th->th_sport = inp->inp_lport; 514 th->th_dport = inp->inp_fport; 515 th->th_seq = 0; 516 th->th_ack = 0; 517 th->th_x2 = 0; 518 th->th_off = 5; 519 th->th_flags = 0; 520 th->th_win = 0; 521 th->th_urp = 0; 522 th->th_sum = 0; /* in_pseudo() is called later for ipv4 */ 523 } 524 525 /* 526 * Create template to be used to send tcp packets on a connection. 527 * Allocates an mbuf and fills in a skeletal tcp/ip header. The only 528 * use for this function is in keepalives, which use tcp_respond. 529 */ 530 struct tcptemp * 531 tcpip_maketemplate(struct inpcb *inp) 532 { 533 struct tcptemp *t; 534 535 t = malloc(sizeof(*t), M_TEMP, M_NOWAIT); 536 if (t == NULL) 537 return (NULL); 538 tcpip_fillheaders(inp, (void *)&t->tt_ipgen, (void *)&t->tt_t); 539 return (t); 540 } 541 542 /* 543 * Send a single message to the TCP at address specified by 544 * the given TCP/IP header. If m == NULL, then we make a copy 545 * of the tcpiphdr at ti and send directly to the addressed host. 546 * This is used to force keep alive messages out using the TCP 547 * template for a connection. If flags are given then we send 548 * a message back to the TCP which originated the * segment ti, 549 * and discard the mbuf containing it and any other attached mbufs. 550 * 551 * In any case the ack and sequence number of the transmitted 552 * segment are as specified by the parameters. 553 * 554 * NOTE: If m != NULL, then ti must point to *inside* the mbuf. 555 */ 556 void 557 tcp_respond(struct tcpcb *tp, void *ipgen, struct tcphdr *th, struct mbuf *m, 558 tcp_seq ack, tcp_seq seq, int flags) 559 { 560 int tlen; 561 int win = 0; 562 struct ip *ip; 563 struct tcphdr *nth; 564 #ifdef INET6 565 struct ip6_hdr *ip6; 566 int isipv6; 567 #endif /* INET6 */ 568 int ipflags = 0; 569 struct inpcb *inp; 570 571 KASSERT(tp != NULL || m != NULL, ("tcp_respond: tp and m both NULL")); 572 573 #ifdef INET6 574 isipv6 = ((struct ip *)ipgen)->ip_v == (IPV6_VERSION >> 4); 575 ip6 = ipgen; 576 #endif /* INET6 */ 577 ip = ipgen; 578 579 if (tp != NULL) { 580 inp = tp->t_inpcb; 581 KASSERT(inp != NULL, ("tcp control block w/o inpcb")); 582 INP_WLOCK_ASSERT(inp); 583 } else 584 inp = NULL; 585 586 if (tp != NULL) { 587 if (!(flags & TH_RST)) { 588 win = sbspace(&inp->inp_socket->so_rcv); 589 if (win > (long)TCP_MAXWIN << tp->rcv_scale) 590 win = (long)TCP_MAXWIN << tp->rcv_scale; 591 } 592 } 593 if (m == NULL) { 594 m = m_gethdr(M_NOWAIT, MT_DATA); 595 if (m == NULL) 596 return; 597 tlen = 0; 598 m->m_data += max_linkhdr; 599 #ifdef INET6 600 if (isipv6) { 601 bcopy((caddr_t)ip6, mtod(m, caddr_t), 602 sizeof(struct ip6_hdr)); 603 ip6 = mtod(m, struct ip6_hdr *); 604 nth = (struct tcphdr *)(ip6 + 1); 605 } else 606 #endif /* INET6 */ 607 { 608 bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip)); 609 ip = mtod(m, struct ip *); 610 nth = (struct tcphdr *)(ip + 1); 611 } 612 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr)); 613 flags = TH_ACK; 614 } else { 615 /* 616 * reuse the mbuf. 617 * XXX MRT We inherrit the FIB, which is lucky. 618 */ 619 m_freem(m->m_next); 620 m->m_next = NULL; 621 m->m_data = (caddr_t)ipgen; 622 /* m_len is set later */ 623 tlen = 0; 624 #define xchg(a,b,type) { type t; t=a; a=b; b=t; } 625 #ifdef INET6 626 if (isipv6) { 627 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); 628 nth = (struct tcphdr *)(ip6 + 1); 629 } else 630 #endif /* INET6 */ 631 { 632 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t); 633 nth = (struct tcphdr *)(ip + 1); 634 } 635 if (th != nth) { 636 /* 637 * this is usually a case when an extension header 638 * exists between the IPv6 header and the 639 * TCP header. 640 */ 641 nth->th_sport = th->th_sport; 642 nth->th_dport = th->th_dport; 643 } 644 xchg(nth->th_dport, nth->th_sport, uint16_t); 645 #undef xchg 646 } 647 #ifdef INET6 648 if (isipv6) { 649 ip6->ip6_flow = 0; 650 ip6->ip6_vfc = IPV6_VERSION; 651 ip6->ip6_nxt = IPPROTO_TCP; 652 tlen += sizeof (struct ip6_hdr) + sizeof (struct tcphdr); 653 ip6->ip6_plen = htons(tlen - sizeof(*ip6)); 654 } 655 #endif 656 #if defined(INET) && defined(INET6) 657 else 658 #endif 659 #ifdef INET 660 { 661 tlen += sizeof (struct tcpiphdr); 662 ip->ip_len = htons(tlen); 663 ip->ip_ttl = V_ip_defttl; 664 if (V_path_mtu_discovery) 665 ip->ip_off |= htons(IP_DF); 666 } 667 #endif 668 m->m_len = tlen; 669 m->m_pkthdr.len = tlen; 670 m->m_pkthdr.rcvif = NULL; 671 #ifdef MAC 672 if (inp != NULL) { 673 /* 674 * Packet is associated with a socket, so allow the 675 * label of the response to reflect the socket label. 676 */ 677 INP_WLOCK_ASSERT(inp); 678 mac_inpcb_create_mbuf(inp, m); 679 } else { 680 /* 681 * Packet is not associated with a socket, so possibly 682 * update the label in place. 683 */ 684 mac_netinet_tcp_reply(m); 685 } 686 #endif 687 nth->th_seq = htonl(seq); 688 nth->th_ack = htonl(ack); 689 nth->th_x2 = 0; 690 nth->th_off = sizeof (struct tcphdr) >> 2; 691 nth->th_flags = flags; 692 if (tp != NULL) 693 nth->th_win = htons((u_short) (win >> tp->rcv_scale)); 694 else 695 nth->th_win = htons((u_short)win); 696 nth->th_urp = 0; 697 698 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); 699 #ifdef INET6 700 if (isipv6) { 701 m->m_pkthdr.csum_flags = CSUM_TCP_IPV6; 702 nth->th_sum = in6_cksum_pseudo(ip6, 703 tlen - sizeof(struct ip6_hdr), IPPROTO_TCP, 0); 704 ip6->ip6_hlim = in6_selecthlim(tp != NULL ? tp->t_inpcb : 705 NULL, NULL); 706 } 707 #endif /* INET6 */ 708 #if defined(INET6) && defined(INET) 709 else 710 #endif 711 #ifdef INET 712 { 713 m->m_pkthdr.csum_flags = CSUM_TCP; 714 nth->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, 715 htons((u_short)(tlen - sizeof(struct ip) + ip->ip_p))); 716 } 717 #endif /* INET */ 718 #ifdef TCPDEBUG 719 if (tp == NULL || (inp->inp_socket->so_options & SO_DEBUG)) 720 tcp_trace(TA_OUTPUT, 0, tp, mtod(m, void *), th, 0); 721 #endif 722 if (flags & TH_RST) 723 TCP_PROBE5(accept__refused, NULL, NULL, mtod(m, const char *), 724 tp, nth); 725 726 TCP_PROBE5(send, NULL, tp, mtod(m, const char *), tp, nth); 727 #ifdef INET6 728 if (isipv6) 729 (void) ip6_output(m, NULL, NULL, ipflags, NULL, NULL, inp); 730 #endif /* INET6 */ 731 #if defined(INET) && defined(INET6) 732 else 733 #endif 734 #ifdef INET 735 (void) ip_output(m, NULL, NULL, ipflags, NULL, inp); 736 #endif 737 } 738 739 /* 740 * Create a new TCP control block, making an 741 * empty reassembly queue and hooking it to the argument 742 * protocol control block. The `inp' parameter must have 743 * come from the zone allocator set up in tcp_init(). 744 */ 745 struct tcpcb * 746 tcp_newtcpcb(struct inpcb *inp) 747 { 748 struct tcpcb_mem *tm; 749 struct tcpcb *tp; 750 #ifdef INET6 751 int isipv6 = (inp->inp_vflag & INP_IPV6) != 0; 752 #endif /* INET6 */ 753 754 tm = uma_zalloc(V_tcpcb_zone, M_NOWAIT | M_ZERO); 755 if (tm == NULL) 756 return (NULL); 757 tp = &tm->tcb; 758 759 /* Initialise cc_var struct for this tcpcb. */ 760 tp->ccv = &tm->ccv; 761 tp->ccv->type = IPPROTO_TCP; 762 tp->ccv->ccvc.tcp = tp; 763 764 /* 765 * Use the current system default CC algorithm. 766 */ 767 CC_LIST_RLOCK(); 768 KASSERT(!STAILQ_EMPTY(&cc_list), ("cc_list is empty!")); 769 CC_ALGO(tp) = CC_DEFAULT(); 770 CC_LIST_RUNLOCK(); 771 772 if (CC_ALGO(tp)->cb_init != NULL) 773 if (CC_ALGO(tp)->cb_init(tp->ccv) > 0) { 774 uma_zfree(V_tcpcb_zone, tm); 775 return (NULL); 776 } 777 778 tp->osd = &tm->osd; 779 if (khelp_init_osd(HELPER_CLASS_TCP, tp->osd)) { 780 uma_zfree(V_tcpcb_zone, tm); 781 return (NULL); 782 } 783 784 #ifdef VIMAGE 785 tp->t_vnet = inp->inp_vnet; 786 #endif 787 tp->t_timers = &tm->tt; 788 /* LIST_INIT(&tp->t_segq); */ /* XXX covered by M_ZERO */ 789 tp->t_maxseg = tp->t_maxopd = 790 #ifdef INET6 791 isipv6 ? V_tcp_v6mssdflt : 792 #endif /* INET6 */ 793 V_tcp_mssdflt; 794 795 /* Set up our timeouts. */ 796 callout_init(&tp->t_timers->tt_rexmt, CALLOUT_MPSAFE); 797 callout_init(&tp->t_timers->tt_persist, CALLOUT_MPSAFE); 798 callout_init(&tp->t_timers->tt_keep, CALLOUT_MPSAFE); 799 callout_init(&tp->t_timers->tt_2msl, CALLOUT_MPSAFE); 800 callout_init(&tp->t_timers->tt_delack, CALLOUT_MPSAFE); 801 802 if (V_tcp_do_rfc1323) 803 tp->t_flags = (TF_REQ_SCALE|TF_REQ_TSTMP); 804 if (V_tcp_do_sack) 805 tp->t_flags |= TF_SACK_PERMIT; 806 TAILQ_INIT(&tp->snd_holes); 807 tp->t_inpcb = inp; /* XXX */ 808 /* 809 * Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no 810 * rtt estimate. Set rttvar so that srtt + 4 * rttvar gives 811 * reasonable initial retransmit time. 812 */ 813 tp->t_srtt = TCPTV_SRTTBASE; 814 tp->t_rttvar = ((TCPTV_RTOBASE - TCPTV_SRTTBASE) << TCP_RTTVAR_SHIFT) / 4; 815 tp->t_rttmin = tcp_rexmit_min; 816 tp->t_rxtcur = TCPTV_RTOBASE; 817 tp->snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT; 818 tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT; 819 tp->t_rcvtime = ticks; 820 /* 821 * IPv4 TTL initialization is necessary for an IPv6 socket as well, 822 * because the socket may be bound to an IPv6 wildcard address, 823 * which may match an IPv4-mapped IPv6 address. 824 */ 825 inp->inp_ip_ttl = V_ip_defttl; 826 inp->inp_ppcb = tp; 827 return (tp); /* XXX */ 828 } 829 830 /* 831 * Switch the congestion control algorithm back to NewReno for any active 832 * control blocks using an algorithm which is about to go away. 833 * This ensures the CC framework can allow the unload to proceed without leaving 834 * any dangling pointers which would trigger a panic. 835 * Returning non-zero would inform the CC framework that something went wrong 836 * and it would be unsafe to allow the unload to proceed. However, there is no 837 * way for this to occur with this implementation so we always return zero. 838 */ 839 int 840 tcp_ccalgounload(struct cc_algo *unload_algo) 841 { 842 struct cc_algo *tmpalgo; 843 struct inpcb *inp; 844 struct tcpcb *tp; 845 VNET_ITERATOR_DECL(vnet_iter); 846 847 /* 848 * Check all active control blocks across all network stacks and change 849 * any that are using "unload_algo" back to NewReno. If "unload_algo" 850 * requires cleanup code to be run, call it. 851 */ 852 VNET_LIST_RLOCK(); 853 VNET_FOREACH(vnet_iter) { 854 CURVNET_SET(vnet_iter); 855 INP_INFO_RLOCK(&V_tcbinfo); 856 /* 857 * New connections already part way through being initialised 858 * with the CC algo we're removing will not race with this code 859 * because the INP_INFO_WLOCK is held during initialisation. We 860 * therefore don't enter the loop below until the connection 861 * list has stabilised. 862 */ 863 LIST_FOREACH(inp, &V_tcb, inp_list) { 864 INP_WLOCK(inp); 865 /* Important to skip tcptw structs. */ 866 if (!(inp->inp_flags & INP_TIMEWAIT) && 867 (tp = intotcpcb(inp)) != NULL) { 868 /* 869 * By holding INP_WLOCK here, we are assured 870 * that the connection is not currently 871 * executing inside the CC module's functions 872 * i.e. it is safe to make the switch back to 873 * NewReno. 874 */ 875 if (CC_ALGO(tp) == unload_algo) { 876 tmpalgo = CC_ALGO(tp); 877 /* NewReno does not require any init. */ 878 CC_ALGO(tp) = &newreno_cc_algo; 879 if (tmpalgo->cb_destroy != NULL) 880 tmpalgo->cb_destroy(tp->ccv); 881 } 882 } 883 INP_WUNLOCK(inp); 884 } 885 INP_INFO_RUNLOCK(&V_tcbinfo); 886 CURVNET_RESTORE(); 887 } 888 VNET_LIST_RUNLOCK(); 889 890 return (0); 891 } 892 893 /* 894 * Drop a TCP connection, reporting 895 * the specified error. If connection is synchronized, 896 * then send a RST to peer. 897 */ 898 struct tcpcb * 899 tcp_drop(struct tcpcb *tp, int errno) 900 { 901 struct socket *so = tp->t_inpcb->inp_socket; 902 903 INP_INFO_WLOCK_ASSERT(&V_tcbinfo); 904 INP_WLOCK_ASSERT(tp->t_inpcb); 905 906 if (TCPS_HAVERCVDSYN(tp->t_state)) { 907 tcp_state_change(tp, TCPS_CLOSED); 908 (void) tcp_output(tp); 909 TCPSTAT_INC(tcps_drops); 910 } else 911 TCPSTAT_INC(tcps_conndrops); 912 if (errno == ETIMEDOUT && tp->t_softerror) 913 errno = tp->t_softerror; 914 so->so_error = errno; 915 return (tcp_close(tp)); 916 } 917 918 void 919 tcp_discardcb(struct tcpcb *tp) 920 { 921 struct inpcb *inp = tp->t_inpcb; 922 struct socket *so = inp->inp_socket; 923 #ifdef INET6 924 int isipv6 = (inp->inp_vflag & INP_IPV6) != 0; 925 #endif /* INET6 */ 926 927 INP_WLOCK_ASSERT(inp); 928 929 /* 930 * Make sure that all of our timers are stopped before we delete the 931 * PCB. 932 * 933 * XXXRW: Really, we would like to use callout_drain() here in order 934 * to avoid races experienced in tcp_timer.c where a timer is already 935 * executing at this point. However, we can't, both because we're 936 * running in a context where we can't sleep, and also because we 937 * hold locks required by the timers. What we instead need to do is 938 * test to see if callout_drain() is required, and if so, defer some 939 * portion of the remainder of tcp_discardcb() to an asynchronous 940 * context that can callout_drain() and then continue. Some care 941 * will be required to ensure that no further processing takes place 942 * on the tcpcb, even though it hasn't been freed (a flag?). 943 */ 944 callout_stop(&tp->t_timers->tt_rexmt); 945 callout_stop(&tp->t_timers->tt_persist); 946 callout_stop(&tp->t_timers->tt_keep); 947 callout_stop(&tp->t_timers->tt_2msl); 948 callout_stop(&tp->t_timers->tt_delack); 949 950 /* 951 * If we got enough samples through the srtt filter, 952 * save the rtt and rttvar in the routing entry. 953 * 'Enough' is arbitrarily defined as 4 rtt samples. 954 * 4 samples is enough for the srtt filter to converge 955 * to within enough % of the correct value; fewer samples 956 * and we could save a bogus rtt. The danger is not high 957 * as tcp quickly recovers from everything. 958 * XXX: Works very well but needs some more statistics! 959 */ 960 if (tp->t_rttupdated >= 4) { 961 struct hc_metrics_lite metrics; 962 u_long ssthresh; 963 964 bzero(&metrics, sizeof(metrics)); 965 /* 966 * Update the ssthresh always when the conditions below 967 * are satisfied. This gives us better new start value 968 * for the congestion avoidance for new connections. 969 * ssthresh is only set if packet loss occured on a session. 970 * 971 * XXXRW: 'so' may be NULL here, and/or socket buffer may be 972 * being torn down. Ideally this code would not use 'so'. 973 */ 974 ssthresh = tp->snd_ssthresh; 975 if (ssthresh != 0 && ssthresh < so->so_snd.sb_hiwat / 2) { 976 /* 977 * convert the limit from user data bytes to 978 * packets then to packet data bytes. 979 */ 980 ssthresh = (ssthresh + tp->t_maxseg / 2) / tp->t_maxseg; 981 if (ssthresh < 2) 982 ssthresh = 2; 983 ssthresh *= (u_long)(tp->t_maxseg + 984 #ifdef INET6 985 (isipv6 ? sizeof (struct ip6_hdr) + 986 sizeof (struct tcphdr) : 987 #endif 988 sizeof (struct tcpiphdr) 989 #ifdef INET6 990 ) 991 #endif 992 ); 993 } else 994 ssthresh = 0; 995 metrics.rmx_ssthresh = ssthresh; 996 997 metrics.rmx_rtt = tp->t_srtt; 998 metrics.rmx_rttvar = tp->t_rttvar; 999 metrics.rmx_cwnd = tp->snd_cwnd; 1000 metrics.rmx_sendpipe = 0; 1001 metrics.rmx_recvpipe = 0; 1002 1003 tcp_hc_update(&inp->inp_inc, &metrics); 1004 } 1005 1006 /* free the reassembly queue, if any */ 1007 tcp_reass_flush(tp); 1008 1009 #ifdef TCP_OFFLOAD 1010 /* Disconnect offload device, if any. */ 1011 if (tp->t_flags & TF_TOE) 1012 tcp_offload_detach(tp); 1013 #endif 1014 1015 tcp_free_sackholes(tp); 1016 1017 /* Allow the CC algorithm to clean up after itself. */ 1018 if (CC_ALGO(tp)->cb_destroy != NULL) 1019 CC_ALGO(tp)->cb_destroy(tp->ccv); 1020 1021 khelp_destroy_osd(tp->osd); 1022 1023 CC_ALGO(tp) = NULL; 1024 inp->inp_ppcb = NULL; 1025 tp->t_inpcb = NULL; 1026 uma_zfree(V_tcpcb_zone, tp); 1027 } 1028 1029 /* 1030 * Attempt to close a TCP control block, marking it as dropped, and freeing 1031 * the socket if we hold the only reference. 1032 */ 1033 struct tcpcb * 1034 tcp_close(struct tcpcb *tp) 1035 { 1036 struct inpcb *inp = tp->t_inpcb; 1037 struct socket *so; 1038 1039 INP_INFO_WLOCK_ASSERT(&V_tcbinfo); 1040 INP_WLOCK_ASSERT(inp); 1041 1042 #ifdef TCP_OFFLOAD 1043 if (tp->t_state == TCPS_LISTEN) 1044 tcp_offload_listen_stop(tp); 1045 #endif 1046 in_pcbdrop(inp); 1047 TCPSTAT_INC(tcps_closed); 1048 KASSERT(inp->inp_socket != NULL, ("tcp_close: inp_socket NULL")); 1049 so = inp->inp_socket; 1050 soisdisconnected(so); 1051 if (inp->inp_flags & INP_SOCKREF) { 1052 KASSERT(so->so_state & SS_PROTOREF, 1053 ("tcp_close: !SS_PROTOREF")); 1054 inp->inp_flags &= ~INP_SOCKREF; 1055 INP_WUNLOCK(inp); 1056 ACCEPT_LOCK(); 1057 SOCK_LOCK(so); 1058 so->so_state &= ~SS_PROTOREF; 1059 sofree(so); 1060 return (NULL); 1061 } 1062 return (tp); 1063 } 1064 1065 void 1066 tcp_drain(void) 1067 { 1068 VNET_ITERATOR_DECL(vnet_iter); 1069 1070 if (!do_tcpdrain) 1071 return; 1072 1073 VNET_LIST_RLOCK_NOSLEEP(); 1074 VNET_FOREACH(vnet_iter) { 1075 CURVNET_SET(vnet_iter); 1076 struct inpcb *inpb; 1077 struct tcpcb *tcpb; 1078 1079 /* 1080 * Walk the tcpbs, if existing, and flush the reassembly queue, 1081 * if there is one... 1082 * XXX: The "Net/3" implementation doesn't imply that the TCP 1083 * reassembly queue should be flushed, but in a situation 1084 * where we're really low on mbufs, this is potentially 1085 * useful. 1086 */ 1087 INP_INFO_RLOCK(&V_tcbinfo); 1088 LIST_FOREACH(inpb, V_tcbinfo.ipi_listhead, inp_list) { 1089 if (inpb->inp_flags & INP_TIMEWAIT) 1090 continue; 1091 INP_WLOCK(inpb); 1092 if ((tcpb = intotcpcb(inpb)) != NULL) { 1093 tcp_reass_flush(tcpb); 1094 tcp_clean_sackreport(tcpb); 1095 } 1096 INP_WUNLOCK(inpb); 1097 } 1098 INP_INFO_RUNLOCK(&V_tcbinfo); 1099 CURVNET_RESTORE(); 1100 } 1101 VNET_LIST_RUNLOCK_NOSLEEP(); 1102 } 1103 1104 /* 1105 * Notify a tcp user of an asynchronous error; 1106 * store error as soft error, but wake up user 1107 * (for now, won't do anything until can select for soft error). 1108 * 1109 * Do not wake up user since there currently is no mechanism for 1110 * reporting soft errors (yet - a kqueue filter may be added). 1111 */ 1112 static struct inpcb * 1113 tcp_notify(struct inpcb *inp, int error) 1114 { 1115 struct tcpcb *tp; 1116 1117 INP_INFO_WLOCK_ASSERT(&V_tcbinfo); 1118 INP_WLOCK_ASSERT(inp); 1119 1120 if ((inp->inp_flags & INP_TIMEWAIT) || 1121 (inp->inp_flags & INP_DROPPED)) 1122 return (inp); 1123 1124 tp = intotcpcb(inp); 1125 KASSERT(tp != NULL, ("tcp_notify: tp == NULL")); 1126 1127 /* 1128 * Ignore some errors if we are hooked up. 1129 * If connection hasn't completed, has retransmitted several times, 1130 * and receives a second error, give up now. This is better 1131 * than waiting a long time to establish a connection that 1132 * can never complete. 1133 */ 1134 if (tp->t_state == TCPS_ESTABLISHED && 1135 (error == EHOSTUNREACH || error == ENETUNREACH || 1136 error == EHOSTDOWN)) { 1137 return (inp); 1138 } else if (tp->t_state < TCPS_ESTABLISHED && tp->t_rxtshift > 3 && 1139 tp->t_softerror) { 1140 tp = tcp_drop(tp, error); 1141 if (tp != NULL) 1142 return (inp); 1143 else 1144 return (NULL); 1145 } else { 1146 tp->t_softerror = error; 1147 return (inp); 1148 } 1149 #if 0 1150 wakeup( &so->so_timeo); 1151 sorwakeup(so); 1152 sowwakeup(so); 1153 #endif 1154 } 1155 1156 static int 1157 tcp_pcblist(SYSCTL_HANDLER_ARGS) 1158 { 1159 int error, i, m, n, pcb_count; 1160 struct inpcb *inp, **inp_list; 1161 inp_gen_t gencnt; 1162 struct xinpgen xig; 1163 1164 /* 1165 * The process of preparing the TCB list is too time-consuming and 1166 * resource-intensive to repeat twice on every request. 1167 */ 1168 if (req->oldptr == NULL) { 1169 n = V_tcbinfo.ipi_count + syncache_pcbcount(); 1170 n += imax(n / 8, 10); 1171 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xtcpcb); 1172 return (0); 1173 } 1174 1175 if (req->newptr != NULL) 1176 return (EPERM); 1177 1178 /* 1179 * OK, now we're committed to doing something. 1180 */ 1181 INP_INFO_RLOCK(&V_tcbinfo); 1182 gencnt = V_tcbinfo.ipi_gencnt; 1183 n = V_tcbinfo.ipi_count; 1184 INP_INFO_RUNLOCK(&V_tcbinfo); 1185 1186 m = syncache_pcbcount(); 1187 1188 error = sysctl_wire_old_buffer(req, 2 * (sizeof xig) 1189 + (n + m) * sizeof(struct xtcpcb)); 1190 if (error != 0) 1191 return (error); 1192 1193 xig.xig_len = sizeof xig; 1194 xig.xig_count = n + m; 1195 xig.xig_gen = gencnt; 1196 xig.xig_sogen = so_gencnt; 1197 error = SYSCTL_OUT(req, &xig, sizeof xig); 1198 if (error) 1199 return (error); 1200 1201 error = syncache_pcblist(req, m, &pcb_count); 1202 if (error) 1203 return (error); 1204 1205 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK); 1206 if (inp_list == NULL) 1207 return (ENOMEM); 1208 1209 INP_INFO_RLOCK(&V_tcbinfo); 1210 for (inp = LIST_FIRST(V_tcbinfo.ipi_listhead), i = 0; 1211 inp != NULL && i < n; inp = LIST_NEXT(inp, inp_list)) { 1212 INP_WLOCK(inp); 1213 if (inp->inp_gencnt <= gencnt) { 1214 /* 1215 * XXX: This use of cr_cansee(), introduced with 1216 * TCP state changes, is not quite right, but for 1217 * now, better than nothing. 1218 */ 1219 if (inp->inp_flags & INP_TIMEWAIT) { 1220 if (intotw(inp) != NULL) 1221 error = cr_cansee(req->td->td_ucred, 1222 intotw(inp)->tw_cred); 1223 else 1224 error = EINVAL; /* Skip this inp. */ 1225 } else 1226 error = cr_canseeinpcb(req->td->td_ucred, inp); 1227 if (error == 0) { 1228 in_pcbref(inp); 1229 inp_list[i++] = inp; 1230 } 1231 } 1232 INP_WUNLOCK(inp); 1233 } 1234 INP_INFO_RUNLOCK(&V_tcbinfo); 1235 n = i; 1236 1237 error = 0; 1238 for (i = 0; i < n; i++) { 1239 inp = inp_list[i]; 1240 INP_RLOCK(inp); 1241 if (inp->inp_gencnt <= gencnt) { 1242 struct xtcpcb xt; 1243 void *inp_ppcb; 1244 1245 bzero(&xt, sizeof(xt)); 1246 xt.xt_len = sizeof xt; 1247 /* XXX should avoid extra copy */ 1248 bcopy(inp, &xt.xt_inp, sizeof *inp); 1249 inp_ppcb = inp->inp_ppcb; 1250 if (inp_ppcb == NULL) 1251 bzero((char *) &xt.xt_tp, sizeof xt.xt_tp); 1252 else if (inp->inp_flags & INP_TIMEWAIT) { 1253 bzero((char *) &xt.xt_tp, sizeof xt.xt_tp); 1254 xt.xt_tp.t_state = TCPS_TIME_WAIT; 1255 } else { 1256 bcopy(inp_ppcb, &xt.xt_tp, sizeof xt.xt_tp); 1257 if (xt.xt_tp.t_timers) 1258 tcp_timer_to_xtimer(&xt.xt_tp, xt.xt_tp.t_timers, &xt.xt_timer); 1259 } 1260 if (inp->inp_socket != NULL) 1261 sotoxsocket(inp->inp_socket, &xt.xt_socket); 1262 else { 1263 bzero(&xt.xt_socket, sizeof xt.xt_socket); 1264 xt.xt_socket.xso_protocol = IPPROTO_TCP; 1265 } 1266 xt.xt_inp.inp_gencnt = inp->inp_gencnt; 1267 INP_RUNLOCK(inp); 1268 error = SYSCTL_OUT(req, &xt, sizeof xt); 1269 } else 1270 INP_RUNLOCK(inp); 1271 } 1272 INP_INFO_WLOCK(&V_tcbinfo); 1273 for (i = 0; i < n; i++) { 1274 inp = inp_list[i]; 1275 INP_RLOCK(inp); 1276 if (!in_pcbrele_rlocked(inp)) 1277 INP_RUNLOCK(inp); 1278 } 1279 INP_INFO_WUNLOCK(&V_tcbinfo); 1280 1281 if (!error) { 1282 /* 1283 * Give the user an updated idea of our state. 1284 * If the generation differs from what we told 1285 * her before, she knows that something happened 1286 * while we were processing this request, and it 1287 * might be necessary to retry. 1288 */ 1289 INP_INFO_RLOCK(&V_tcbinfo); 1290 xig.xig_gen = V_tcbinfo.ipi_gencnt; 1291 xig.xig_sogen = so_gencnt; 1292 xig.xig_count = V_tcbinfo.ipi_count + pcb_count; 1293 INP_INFO_RUNLOCK(&V_tcbinfo); 1294 error = SYSCTL_OUT(req, &xig, sizeof xig); 1295 } 1296 free(inp_list, M_TEMP); 1297 return (error); 1298 } 1299 1300 SYSCTL_PROC(_net_inet_tcp, TCPCTL_PCBLIST, pcblist, 1301 CTLTYPE_OPAQUE | CTLFLAG_RD, NULL, 0, 1302 tcp_pcblist, "S,xtcpcb", "List of active TCP connections"); 1303 1304 #ifdef INET 1305 static int 1306 tcp_getcred(SYSCTL_HANDLER_ARGS) 1307 { 1308 struct xucred xuc; 1309 struct sockaddr_in addrs[2]; 1310 struct inpcb *inp; 1311 int error; 1312 1313 error = priv_check(req->td, PRIV_NETINET_GETCRED); 1314 if (error) 1315 return (error); 1316 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 1317 if (error) 1318 return (error); 1319 inp = in_pcblookup(&V_tcbinfo, addrs[1].sin_addr, addrs[1].sin_port, 1320 addrs[0].sin_addr, addrs[0].sin_port, INPLOOKUP_RLOCKPCB, NULL); 1321 if (inp != NULL) { 1322 if (inp->inp_socket == NULL) 1323 error = ENOENT; 1324 if (error == 0) 1325 error = cr_canseeinpcb(req->td->td_ucred, inp); 1326 if (error == 0) 1327 cru2x(inp->inp_cred, &xuc); 1328 INP_RUNLOCK(inp); 1329 } else 1330 error = ENOENT; 1331 if (error == 0) 1332 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 1333 return (error); 1334 } 1335 1336 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, getcred, 1337 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0, 1338 tcp_getcred, "S,xucred", "Get the xucred of a TCP connection"); 1339 #endif /* INET */ 1340 1341 #ifdef INET6 1342 static int 1343 tcp6_getcred(SYSCTL_HANDLER_ARGS) 1344 { 1345 struct xucred xuc; 1346 struct sockaddr_in6 addrs[2]; 1347 struct inpcb *inp; 1348 int error; 1349 #ifdef INET 1350 int mapped = 0; 1351 #endif 1352 1353 error = priv_check(req->td, PRIV_NETINET_GETCRED); 1354 if (error) 1355 return (error); 1356 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 1357 if (error) 1358 return (error); 1359 if ((error = sa6_embedscope(&addrs[0], V_ip6_use_defzone)) != 0 || 1360 (error = sa6_embedscope(&addrs[1], V_ip6_use_defzone)) != 0) { 1361 return (error); 1362 } 1363 if (IN6_IS_ADDR_V4MAPPED(&addrs[0].sin6_addr)) { 1364 #ifdef INET 1365 if (IN6_IS_ADDR_V4MAPPED(&addrs[1].sin6_addr)) 1366 mapped = 1; 1367 else 1368 #endif 1369 return (EINVAL); 1370 } 1371 1372 #ifdef INET 1373 if (mapped == 1) 1374 inp = in_pcblookup(&V_tcbinfo, 1375 *(struct in_addr *)&addrs[1].sin6_addr.s6_addr[12], 1376 addrs[1].sin6_port, 1377 *(struct in_addr *)&addrs[0].sin6_addr.s6_addr[12], 1378 addrs[0].sin6_port, INPLOOKUP_RLOCKPCB, NULL); 1379 else 1380 #endif 1381 inp = in6_pcblookup(&V_tcbinfo, 1382 &addrs[1].sin6_addr, addrs[1].sin6_port, 1383 &addrs[0].sin6_addr, addrs[0].sin6_port, 1384 INPLOOKUP_RLOCKPCB, NULL); 1385 if (inp != NULL) { 1386 if (inp->inp_socket == NULL) 1387 error = ENOENT; 1388 if (error == 0) 1389 error = cr_canseeinpcb(req->td->td_ucred, inp); 1390 if (error == 0) 1391 cru2x(inp->inp_cred, &xuc); 1392 INP_RUNLOCK(inp); 1393 } else 1394 error = ENOENT; 1395 if (error == 0) 1396 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 1397 return (error); 1398 } 1399 1400 SYSCTL_PROC(_net_inet6_tcp6, OID_AUTO, getcred, 1401 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0, 1402 tcp6_getcred, "S,xucred", "Get the xucred of a TCP6 connection"); 1403 #endif /* INET6 */ 1404 1405 1406 #ifdef INET 1407 void 1408 tcp_ctlinput(int cmd, struct sockaddr *sa, void *vip) 1409 { 1410 struct ip *ip = vip; 1411 struct tcphdr *th; 1412 struct in_addr faddr; 1413 struct inpcb *inp; 1414 struct tcpcb *tp; 1415 struct inpcb *(*notify)(struct inpcb *, int) = tcp_notify; 1416 struct icmp *icp; 1417 struct in_conninfo inc; 1418 tcp_seq icmp_tcp_seq; 1419 int mtu; 1420 1421 faddr = ((struct sockaddr_in *)sa)->sin_addr; 1422 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY) 1423 return; 1424 1425 if (cmd == PRC_MSGSIZE) 1426 notify = tcp_mtudisc_notify; 1427 else if (V_icmp_may_rst && (cmd == PRC_UNREACH_ADMIN_PROHIB || 1428 cmd == PRC_UNREACH_PORT || cmd == PRC_TIMXCEED_INTRANS) && ip) 1429 notify = tcp_drop_syn_sent; 1430 /* 1431 * Redirects don't need to be handled up here. 1432 */ 1433 else if (PRC_IS_REDIRECT(cmd)) 1434 return; 1435 /* 1436 * Source quench is depreciated. 1437 */ 1438 else if (cmd == PRC_QUENCH) 1439 return; 1440 /* 1441 * Hostdead is ugly because it goes linearly through all PCBs. 1442 * XXX: We never get this from ICMP, otherwise it makes an 1443 * excellent DoS attack on machines with many connections. 1444 */ 1445 else if (cmd == PRC_HOSTDEAD) 1446 ip = NULL; 1447 else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0) 1448 return; 1449 if (ip != NULL) { 1450 icp = (struct icmp *)((caddr_t)ip 1451 - offsetof(struct icmp, icmp_ip)); 1452 th = (struct tcphdr *)((caddr_t)ip 1453 + (ip->ip_hl << 2)); 1454 INP_INFO_WLOCK(&V_tcbinfo); 1455 inp = in_pcblookup(&V_tcbinfo, faddr, th->th_dport, 1456 ip->ip_src, th->th_sport, INPLOOKUP_WLOCKPCB, NULL); 1457 if (inp != NULL) { 1458 if (!(inp->inp_flags & INP_TIMEWAIT) && 1459 !(inp->inp_flags & INP_DROPPED) && 1460 !(inp->inp_socket == NULL)) { 1461 icmp_tcp_seq = htonl(th->th_seq); 1462 tp = intotcpcb(inp); 1463 if (SEQ_GEQ(icmp_tcp_seq, tp->snd_una) && 1464 SEQ_LT(icmp_tcp_seq, tp->snd_max)) { 1465 if (cmd == PRC_MSGSIZE) { 1466 /* 1467 * MTU discovery: 1468 * If we got a needfrag set the MTU 1469 * in the route to the suggested new 1470 * value (if given) and then notify. 1471 */ 1472 bzero(&inc, sizeof(inc)); 1473 inc.inc_faddr = faddr; 1474 inc.inc_fibnum = 1475 inp->inp_inc.inc_fibnum; 1476 1477 mtu = ntohs(icp->icmp_nextmtu); 1478 /* 1479 * If no alternative MTU was 1480 * proposed, try the next smaller 1481 * one. 1482 */ 1483 if (!mtu) 1484 mtu = ip_next_mtu( 1485 ntohs(ip->ip_len), 1); 1486 if (mtu < V_tcp_minmss 1487 + sizeof(struct tcpiphdr)) 1488 mtu = V_tcp_minmss 1489 + sizeof(struct tcpiphdr); 1490 /* 1491 * Only cache the MTU if it 1492 * is smaller than the interface 1493 * or route MTU. tcp_mtudisc() 1494 * will do right thing by itself. 1495 */ 1496 if (mtu <= tcp_maxmtu(&inc, NULL)) 1497 tcp_hc_updatemtu(&inc, mtu); 1498 tcp_mtudisc(inp, mtu); 1499 } else 1500 inp = (*notify)(inp, 1501 inetctlerrmap[cmd]); 1502 } 1503 } 1504 if (inp != NULL) 1505 INP_WUNLOCK(inp); 1506 } else { 1507 bzero(&inc, sizeof(inc)); 1508 inc.inc_fport = th->th_dport; 1509 inc.inc_lport = th->th_sport; 1510 inc.inc_faddr = faddr; 1511 inc.inc_laddr = ip->ip_src; 1512 syncache_unreach(&inc, th); 1513 } 1514 INP_INFO_WUNLOCK(&V_tcbinfo); 1515 } else 1516 in_pcbnotifyall(&V_tcbinfo, faddr, inetctlerrmap[cmd], notify); 1517 } 1518 #endif /* INET */ 1519 1520 #ifdef INET6 1521 void 1522 tcp6_ctlinput(int cmd, struct sockaddr *sa, void *d) 1523 { 1524 struct tcphdr th; 1525 struct inpcb *(*notify)(struct inpcb *, int) = tcp_notify; 1526 struct ip6_hdr *ip6; 1527 struct mbuf *m; 1528 struct ip6ctlparam *ip6cp = NULL; 1529 const struct sockaddr_in6 *sa6_src = NULL; 1530 int off; 1531 struct tcp_portonly { 1532 u_int16_t th_sport; 1533 u_int16_t th_dport; 1534 } *thp; 1535 1536 if (sa->sa_family != AF_INET6 || 1537 sa->sa_len != sizeof(struct sockaddr_in6)) 1538 return; 1539 1540 if (cmd == PRC_MSGSIZE) 1541 notify = tcp_mtudisc_notify; 1542 else if (!PRC_IS_REDIRECT(cmd) && 1543 ((unsigned)cmd >= PRC_NCMDS || inet6ctlerrmap[cmd] == 0)) 1544 return; 1545 /* Source quench is depreciated. */ 1546 else if (cmd == PRC_QUENCH) 1547 return; 1548 1549 /* if the parameter is from icmp6, decode it. */ 1550 if (d != NULL) { 1551 ip6cp = (struct ip6ctlparam *)d; 1552 m = ip6cp->ip6c_m; 1553 ip6 = ip6cp->ip6c_ip6; 1554 off = ip6cp->ip6c_off; 1555 sa6_src = ip6cp->ip6c_src; 1556 } else { 1557 m = NULL; 1558 ip6 = NULL; 1559 off = 0; /* fool gcc */ 1560 sa6_src = &sa6_any; 1561 } 1562 1563 if (ip6 != NULL) { 1564 struct in_conninfo inc; 1565 /* 1566 * XXX: We assume that when IPV6 is non NULL, 1567 * M and OFF are valid. 1568 */ 1569 1570 /* check if we can safely examine src and dst ports */ 1571 if (m->m_pkthdr.len < off + sizeof(*thp)) 1572 return; 1573 1574 bzero(&th, sizeof(th)); 1575 m_copydata(m, off, sizeof(*thp), (caddr_t)&th); 1576 1577 in6_pcbnotify(&V_tcbinfo, sa, th.th_dport, 1578 (struct sockaddr *)ip6cp->ip6c_src, 1579 th.th_sport, cmd, NULL, notify); 1580 1581 bzero(&inc, sizeof(inc)); 1582 inc.inc_fport = th.th_dport; 1583 inc.inc_lport = th.th_sport; 1584 inc.inc6_faddr = ((struct sockaddr_in6 *)sa)->sin6_addr; 1585 inc.inc6_laddr = ip6cp->ip6c_src->sin6_addr; 1586 inc.inc_flags |= INC_ISIPV6; 1587 INP_INFO_WLOCK(&V_tcbinfo); 1588 syncache_unreach(&inc, &th); 1589 INP_INFO_WUNLOCK(&V_tcbinfo); 1590 } else 1591 in6_pcbnotify(&V_tcbinfo, sa, 0, (const struct sockaddr *)sa6_src, 1592 0, cmd, NULL, notify); 1593 } 1594 #endif /* INET6 */ 1595 1596 1597 /* 1598 * Following is where TCP initial sequence number generation occurs. 1599 * 1600 * There are two places where we must use initial sequence numbers: 1601 * 1. In SYN-ACK packets. 1602 * 2. In SYN packets. 1603 * 1604 * All ISNs for SYN-ACK packets are generated by the syncache. See 1605 * tcp_syncache.c for details. 1606 * 1607 * The ISNs in SYN packets must be monotonic; TIME_WAIT recycling 1608 * depends on this property. In addition, these ISNs should be 1609 * unguessable so as to prevent connection hijacking. To satisfy 1610 * the requirements of this situation, the algorithm outlined in 1611 * RFC 1948 is used, with only small modifications. 1612 * 1613 * Implementation details: 1614 * 1615 * Time is based off the system timer, and is corrected so that it 1616 * increases by one megabyte per second. This allows for proper 1617 * recycling on high speed LANs while still leaving over an hour 1618 * before rollover. 1619 * 1620 * As reading the *exact* system time is too expensive to be done 1621 * whenever setting up a TCP connection, we increment the time 1622 * offset in two ways. First, a small random positive increment 1623 * is added to isn_offset for each connection that is set up. 1624 * Second, the function tcp_isn_tick fires once per clock tick 1625 * and increments isn_offset as necessary so that sequence numbers 1626 * are incremented at approximately ISN_BYTES_PER_SECOND. The 1627 * random positive increments serve only to ensure that the same 1628 * exact sequence number is never sent out twice (as could otherwise 1629 * happen when a port is recycled in less than the system tick 1630 * interval.) 1631 * 1632 * net.inet.tcp.isn_reseed_interval controls the number of seconds 1633 * between seeding of isn_secret. This is normally set to zero, 1634 * as reseeding should not be necessary. 1635 * 1636 * Locking of the global variables isn_secret, isn_last_reseed, isn_offset, 1637 * isn_offset_old, and isn_ctx is performed using the TCP pcbinfo lock. In 1638 * general, this means holding an exclusive (write) lock. 1639 */ 1640 1641 #define ISN_BYTES_PER_SECOND 1048576 1642 #define ISN_STATIC_INCREMENT 4096 1643 #define ISN_RANDOM_INCREMENT (4096 - 1) 1644 1645 static VNET_DEFINE(u_char, isn_secret[32]); 1646 static VNET_DEFINE(int, isn_last); 1647 static VNET_DEFINE(int, isn_last_reseed); 1648 static VNET_DEFINE(u_int32_t, isn_offset); 1649 static VNET_DEFINE(u_int32_t, isn_offset_old); 1650 1651 #define V_isn_secret VNET(isn_secret) 1652 #define V_isn_last VNET(isn_last) 1653 #define V_isn_last_reseed VNET(isn_last_reseed) 1654 #define V_isn_offset VNET(isn_offset) 1655 #define V_isn_offset_old VNET(isn_offset_old) 1656 1657 tcp_seq 1658 tcp_new_isn(struct tcpcb *tp) 1659 { 1660 MD5_CTX isn_ctx; 1661 u_int32_t md5_buffer[4]; 1662 tcp_seq new_isn; 1663 u_int32_t projected_offset; 1664 1665 INP_WLOCK_ASSERT(tp->t_inpcb); 1666 1667 ISN_LOCK(); 1668 /* Seed if this is the first use, reseed if requested. */ 1669 if ((V_isn_last_reseed == 0) || ((V_tcp_isn_reseed_interval > 0) && 1670 (((u_int)V_isn_last_reseed + (u_int)V_tcp_isn_reseed_interval*hz) 1671 < (u_int)ticks))) { 1672 read_random(&V_isn_secret, sizeof(V_isn_secret)); 1673 V_isn_last_reseed = ticks; 1674 } 1675 1676 /* Compute the md5 hash and return the ISN. */ 1677 MD5Init(&isn_ctx); 1678 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_fport, sizeof(u_short)); 1679 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_lport, sizeof(u_short)); 1680 #ifdef INET6 1681 if ((tp->t_inpcb->inp_vflag & INP_IPV6) != 0) { 1682 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->in6p_faddr, 1683 sizeof(struct in6_addr)); 1684 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->in6p_laddr, 1685 sizeof(struct in6_addr)); 1686 } else 1687 #endif 1688 { 1689 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_faddr, 1690 sizeof(struct in_addr)); 1691 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_laddr, 1692 sizeof(struct in_addr)); 1693 } 1694 MD5Update(&isn_ctx, (u_char *) &V_isn_secret, sizeof(V_isn_secret)); 1695 MD5Final((u_char *) &md5_buffer, &isn_ctx); 1696 new_isn = (tcp_seq) md5_buffer[0]; 1697 V_isn_offset += ISN_STATIC_INCREMENT + 1698 (arc4random() & ISN_RANDOM_INCREMENT); 1699 if (ticks != V_isn_last) { 1700 projected_offset = V_isn_offset_old + 1701 ISN_BYTES_PER_SECOND / hz * (ticks - V_isn_last); 1702 if (SEQ_GT(projected_offset, V_isn_offset)) 1703 V_isn_offset = projected_offset; 1704 V_isn_offset_old = V_isn_offset; 1705 V_isn_last = ticks; 1706 } 1707 new_isn += V_isn_offset; 1708 ISN_UNLOCK(); 1709 return (new_isn); 1710 } 1711 1712 /* 1713 * When a specific ICMP unreachable message is received and the 1714 * connection state is SYN-SENT, drop the connection. This behavior 1715 * is controlled by the icmp_may_rst sysctl. 1716 */ 1717 struct inpcb * 1718 tcp_drop_syn_sent(struct inpcb *inp, int errno) 1719 { 1720 struct tcpcb *tp; 1721 1722 INP_INFO_WLOCK_ASSERT(&V_tcbinfo); 1723 INP_WLOCK_ASSERT(inp); 1724 1725 if ((inp->inp_flags & INP_TIMEWAIT) || 1726 (inp->inp_flags & INP_DROPPED)) 1727 return (inp); 1728 1729 tp = intotcpcb(inp); 1730 if (tp->t_state != TCPS_SYN_SENT) 1731 return (inp); 1732 1733 tp = tcp_drop(tp, errno); 1734 if (tp != NULL) 1735 return (inp); 1736 else 1737 return (NULL); 1738 } 1739 1740 /* 1741 * When `need fragmentation' ICMP is received, update our idea of the MSS 1742 * based on the new value. Also nudge TCP to send something, since we 1743 * know the packet we just sent was dropped. 1744 * This duplicates some code in the tcp_mss() function in tcp_input.c. 1745 */ 1746 static struct inpcb * 1747 tcp_mtudisc_notify(struct inpcb *inp, int error) 1748 { 1749 1750 return (tcp_mtudisc(inp, -1)); 1751 } 1752 1753 struct inpcb * 1754 tcp_mtudisc(struct inpcb *inp, int mtuoffer) 1755 { 1756 struct tcpcb *tp; 1757 struct socket *so; 1758 1759 INP_WLOCK_ASSERT(inp); 1760 if ((inp->inp_flags & INP_TIMEWAIT) || 1761 (inp->inp_flags & INP_DROPPED)) 1762 return (inp); 1763 1764 tp = intotcpcb(inp); 1765 KASSERT(tp != NULL, ("tcp_mtudisc: tp == NULL")); 1766 1767 tcp_mss_update(tp, -1, mtuoffer, NULL, NULL); 1768 1769 so = inp->inp_socket; 1770 SOCKBUF_LOCK(&so->so_snd); 1771 /* If the mss is larger than the socket buffer, decrease the mss. */ 1772 if (so->so_snd.sb_hiwat < tp->t_maxseg) 1773 tp->t_maxseg = so->so_snd.sb_hiwat; 1774 SOCKBUF_UNLOCK(&so->so_snd); 1775 1776 TCPSTAT_INC(tcps_mturesent); 1777 tp->t_rtttime = 0; 1778 tp->snd_nxt = tp->snd_una; 1779 tcp_free_sackholes(tp); 1780 tp->snd_recover = tp->snd_max; 1781 if (tp->t_flags & TF_SACK_PERMIT) 1782 EXIT_FASTRECOVERY(tp->t_flags); 1783 tcp_output(tp); 1784 return (inp); 1785 } 1786 1787 #ifdef INET 1788 /* 1789 * Look-up the routing entry to the peer of this inpcb. If no route 1790 * is found and it cannot be allocated, then return 0. This routine 1791 * is called by TCP routines that access the rmx structure and by 1792 * tcp_mss_update to get the peer/interface MTU. 1793 */ 1794 u_long 1795 tcp_maxmtu(struct in_conninfo *inc, struct tcp_ifcap *cap) 1796 { 1797 struct route sro; 1798 struct sockaddr_in *dst; 1799 struct ifnet *ifp; 1800 u_long maxmtu = 0; 1801 1802 KASSERT(inc != NULL, ("tcp_maxmtu with NULL in_conninfo pointer")); 1803 1804 bzero(&sro, sizeof(sro)); 1805 if (inc->inc_faddr.s_addr != INADDR_ANY) { 1806 dst = (struct sockaddr_in *)&sro.ro_dst; 1807 dst->sin_family = AF_INET; 1808 dst->sin_len = sizeof(*dst); 1809 dst->sin_addr = inc->inc_faddr; 1810 in_rtalloc_ign(&sro, 0, inc->inc_fibnum); 1811 } 1812 if (sro.ro_rt != NULL) { 1813 ifp = sro.ro_rt->rt_ifp; 1814 if (sro.ro_rt->rt_rmx.rmx_mtu == 0) 1815 maxmtu = ifp->if_mtu; 1816 else 1817 maxmtu = min(sro.ro_rt->rt_rmx.rmx_mtu, ifp->if_mtu); 1818 1819 /* Report additional interface capabilities. */ 1820 if (cap != NULL) { 1821 if (ifp->if_capenable & IFCAP_TSO4 && 1822 ifp->if_hwassist & CSUM_TSO) 1823 cap->ifcap |= CSUM_TSO; 1824 cap->tsomax = ifp->if_hw_tsomax; 1825 } 1826 RTFREE(sro.ro_rt); 1827 } 1828 return (maxmtu); 1829 } 1830 #endif /* INET */ 1831 1832 #ifdef INET6 1833 u_long 1834 tcp_maxmtu6(struct in_conninfo *inc, struct tcp_ifcap *cap) 1835 { 1836 struct route_in6 sro6; 1837 struct ifnet *ifp; 1838 u_long maxmtu = 0; 1839 1840 KASSERT(inc != NULL, ("tcp_maxmtu6 with NULL in_conninfo pointer")); 1841 1842 bzero(&sro6, sizeof(sro6)); 1843 if (!IN6_IS_ADDR_UNSPECIFIED(&inc->inc6_faddr)) { 1844 sro6.ro_dst.sin6_family = AF_INET6; 1845 sro6.ro_dst.sin6_len = sizeof(struct sockaddr_in6); 1846 sro6.ro_dst.sin6_addr = inc->inc6_faddr; 1847 in6_rtalloc_ign(&sro6, 0, inc->inc_fibnum); 1848 } 1849 if (sro6.ro_rt != NULL) { 1850 ifp = sro6.ro_rt->rt_ifp; 1851 if (sro6.ro_rt->rt_rmx.rmx_mtu == 0) 1852 maxmtu = IN6_LINKMTU(sro6.ro_rt->rt_ifp); 1853 else 1854 maxmtu = min(sro6.ro_rt->rt_rmx.rmx_mtu, 1855 IN6_LINKMTU(sro6.ro_rt->rt_ifp)); 1856 1857 /* Report additional interface capabilities. */ 1858 if (cap != NULL) { 1859 if (ifp->if_capenable & IFCAP_TSO6 && 1860 ifp->if_hwassist & CSUM_TSO) 1861 cap->ifcap |= CSUM_TSO; 1862 cap->tsomax = ifp->if_hw_tsomax; 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