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