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/eventhandler.h> 45 #ifdef TCP_HHOOK 46 #include <sys/hhook.h> 47 #endif 48 #include <sys/kernel.h> 49 #ifdef TCP_HHOOK 50 #include <sys/khelp.h> 51 #endif 52 #include <sys/sysctl.h> 53 #include <sys/jail.h> 54 #include <sys/malloc.h> 55 #include <sys/refcount.h> 56 #include <sys/mbuf.h> 57 #ifdef INET6 58 #include <sys/domain.h> 59 #endif 60 #include <sys/priv.h> 61 #include <sys/proc.h> 62 #include <sys/sdt.h> 63 #include <sys/socket.h> 64 #include <sys/socketvar.h> 65 #include <sys/protosw.h> 66 #include <sys/random.h> 67 68 #include <vm/uma.h> 69 70 #include <net/route.h> 71 #include <net/if.h> 72 #include <net/if_var.h> 73 #include <net/vnet.h> 74 75 #include <netinet/in.h> 76 #include <netinet/in_fib.h> 77 #include <netinet/in_kdtrace.h> 78 #include <netinet/in_pcb.h> 79 #include <netinet/in_systm.h> 80 #include <netinet/in_var.h> 81 #include <netinet/ip.h> 82 #include <netinet/ip_icmp.h> 83 #include <netinet/ip_var.h> 84 #ifdef INET6 85 #include <netinet/icmp6.h> 86 #include <netinet/ip6.h> 87 #include <netinet6/in6_fib.h> 88 #include <netinet6/in6_pcb.h> 89 #include <netinet6/ip6_var.h> 90 #include <netinet6/scope6_var.h> 91 #include <netinet6/nd6.h> 92 #endif 93 94 #ifdef TCP_RFC7413 95 #include <netinet/tcp_fastopen.h> 96 #endif 97 #include <netinet/tcp.h> 98 #include <netinet/tcp_fsm.h> 99 #include <netinet/tcp_seq.h> 100 #include <netinet/tcp_timer.h> 101 #include <netinet/tcp_var.h> 102 #include <netinet/tcp_syncache.h> 103 #include <netinet/cc/cc.h> 104 #ifdef INET6 105 #include <netinet6/tcp6_var.h> 106 #endif 107 #include <netinet/tcpip.h> 108 #ifdef TCPPCAP 109 #include <netinet/tcp_pcap.h> 110 #endif 111 #ifdef TCPDEBUG 112 #include <netinet/tcp_debug.h> 113 #endif 114 #ifdef INET6 115 #include <netinet6/ip6protosw.h> 116 #endif 117 #ifdef TCP_OFFLOAD 118 #include <netinet/tcp_offload.h> 119 #endif 120 121 #ifdef IPSEC 122 #include <netipsec/ipsec.h> 123 #include <netipsec/xform.h> 124 #ifdef INET6 125 #include <netipsec/ipsec6.h> 126 #endif 127 #include <netipsec/key.h> 128 #include <sys/syslog.h> 129 #endif /*IPSEC*/ 130 131 #include <machine/in_cksum.h> 132 #include <sys/md5.h> 133 134 #include <security/mac/mac_framework.h> 135 136 VNET_DEFINE(int, tcp_mssdflt) = TCP_MSS; 137 #ifdef INET6 138 VNET_DEFINE(int, tcp_v6mssdflt) = TCP6_MSS; 139 #endif 140 141 struct rwlock tcp_function_lock; 142 143 static int 144 sysctl_net_inet_tcp_mss_check(SYSCTL_HANDLER_ARGS) 145 { 146 int error, new; 147 148 new = V_tcp_mssdflt; 149 error = sysctl_handle_int(oidp, &new, 0, req); 150 if (error == 0 && req->newptr) { 151 if (new < TCP_MINMSS) 152 error = EINVAL; 153 else 154 V_tcp_mssdflt = new; 155 } 156 return (error); 157 } 158 159 SYSCTL_PROC(_net_inet_tcp, TCPCTL_MSSDFLT, mssdflt, 160 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW, &VNET_NAME(tcp_mssdflt), 0, 161 &sysctl_net_inet_tcp_mss_check, "I", 162 "Default TCP Maximum Segment Size"); 163 164 #ifdef INET6 165 static int 166 sysctl_net_inet_tcp_mss_v6_check(SYSCTL_HANDLER_ARGS) 167 { 168 int error, new; 169 170 new = V_tcp_v6mssdflt; 171 error = sysctl_handle_int(oidp, &new, 0, req); 172 if (error == 0 && req->newptr) { 173 if (new < TCP_MINMSS) 174 error = EINVAL; 175 else 176 V_tcp_v6mssdflt = new; 177 } 178 return (error); 179 } 180 181 SYSCTL_PROC(_net_inet_tcp, TCPCTL_V6MSSDFLT, v6mssdflt, 182 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW, &VNET_NAME(tcp_v6mssdflt), 0, 183 &sysctl_net_inet_tcp_mss_v6_check, "I", 184 "Default TCP Maximum Segment Size for IPv6"); 185 #endif /* INET6 */ 186 187 /* 188 * Minimum MSS we accept and use. This prevents DoS attacks where 189 * we are forced to a ridiculous low MSS like 20 and send hundreds 190 * of packets instead of one. The effect scales with the available 191 * bandwidth and quickly saturates the CPU and network interface 192 * with packet generation and sending. Set to zero to disable MINMSS 193 * checking. This setting prevents us from sending too small packets. 194 */ 195 VNET_DEFINE(int, tcp_minmss) = TCP_MINMSS; 196 SYSCTL_INT(_net_inet_tcp, OID_AUTO, minmss, CTLFLAG_VNET | CTLFLAG_RW, 197 &VNET_NAME(tcp_minmss), 0, 198 "Minimum TCP Maximum Segment Size"); 199 200 VNET_DEFINE(int, tcp_do_rfc1323) = 1; 201 SYSCTL_INT(_net_inet_tcp, TCPCTL_DO_RFC1323, rfc1323, CTLFLAG_VNET | CTLFLAG_RW, 202 &VNET_NAME(tcp_do_rfc1323), 0, 203 "Enable rfc1323 (high performance TCP) extensions"); 204 205 static int tcp_log_debug = 0; 206 SYSCTL_INT(_net_inet_tcp, OID_AUTO, log_debug, CTLFLAG_RW, 207 &tcp_log_debug, 0, "Log errors caused by incoming TCP segments"); 208 209 static int tcp_tcbhashsize; 210 SYSCTL_INT(_net_inet_tcp, OID_AUTO, tcbhashsize, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, 211 &tcp_tcbhashsize, 0, "Size of TCP control-block hashtable"); 212 213 static int do_tcpdrain = 1; 214 SYSCTL_INT(_net_inet_tcp, OID_AUTO, do_tcpdrain, CTLFLAG_RW, &do_tcpdrain, 0, 215 "Enable tcp_drain routine for extra help when low on mbufs"); 216 217 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, pcbcount, CTLFLAG_VNET | CTLFLAG_RD, 218 &VNET_NAME(tcbinfo.ipi_count), 0, "Number of active PCBs"); 219 220 static VNET_DEFINE(int, icmp_may_rst) = 1; 221 #define V_icmp_may_rst VNET(icmp_may_rst) 222 SYSCTL_INT(_net_inet_tcp, OID_AUTO, icmp_may_rst, CTLFLAG_VNET | CTLFLAG_RW, 223 &VNET_NAME(icmp_may_rst), 0, 224 "Certain ICMP unreachable messages may abort connections in SYN_SENT"); 225 226 static VNET_DEFINE(int, tcp_isn_reseed_interval) = 0; 227 #define V_tcp_isn_reseed_interval VNET(tcp_isn_reseed_interval) 228 SYSCTL_INT(_net_inet_tcp, OID_AUTO, isn_reseed_interval, CTLFLAG_VNET | CTLFLAG_RW, 229 &VNET_NAME(tcp_isn_reseed_interval), 0, 230 "Seconds between reseeding of ISN secret"); 231 232 static int tcp_soreceive_stream; 233 SYSCTL_INT(_net_inet_tcp, OID_AUTO, soreceive_stream, CTLFLAG_RDTUN, 234 &tcp_soreceive_stream, 0, "Using soreceive_stream for TCP sockets"); 235 236 #ifdef TCP_SIGNATURE 237 static int tcp_sig_checksigs = 1; 238 SYSCTL_INT(_net_inet_tcp, OID_AUTO, signature_verify_input, CTLFLAG_RW, 239 &tcp_sig_checksigs, 0, "Verify RFC2385 digests on inbound traffic"); 240 #endif 241 242 VNET_DEFINE(uma_zone_t, sack_hole_zone); 243 #define V_sack_hole_zone VNET(sack_hole_zone) 244 245 #ifdef TCP_HHOOK 246 VNET_DEFINE(struct hhook_head *, tcp_hhh[HHOOK_TCP_LAST+1]); 247 #endif 248 249 static struct inpcb *tcp_notify(struct inpcb *, int); 250 static struct inpcb *tcp_mtudisc_notify(struct inpcb *, int); 251 static void tcp_mtudisc(struct inpcb *, int); 252 static char * tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th, 253 void *ip4hdr, const void *ip6hdr); 254 255 256 static struct tcp_function_block tcp_def_funcblk = { 257 "default", 258 tcp_output, 259 tcp_do_segment, 260 tcp_default_ctloutput, 261 NULL, 262 NULL, 263 NULL, 264 NULL, 265 NULL, 266 NULL, 267 0, 268 0 269 }; 270 271 int t_functions_inited = 0; 272 struct tcp_funchead t_functions; 273 static struct tcp_function_block *tcp_func_set_ptr = &tcp_def_funcblk; 274 275 static void 276 init_tcp_functions(void) 277 { 278 if (t_functions_inited == 0) { 279 TAILQ_INIT(&t_functions); 280 rw_init_flags(&tcp_function_lock, "tcp_func_lock" , 0); 281 t_functions_inited = 1; 282 } 283 } 284 285 static struct tcp_function_block * 286 find_tcp_functions_locked(struct tcp_function_set *fs) 287 { 288 struct tcp_function *f; 289 struct tcp_function_block *blk=NULL; 290 291 TAILQ_FOREACH(f, &t_functions, tf_next) { 292 if (strcmp(f->tf_fb->tfb_tcp_block_name, fs->function_set_name) == 0) { 293 blk = f->tf_fb; 294 break; 295 } 296 } 297 return(blk); 298 } 299 300 static struct tcp_function_block * 301 find_tcp_fb_locked(struct tcp_function_block *blk, struct tcp_function **s) 302 { 303 struct tcp_function_block *rblk=NULL; 304 struct tcp_function *f; 305 306 TAILQ_FOREACH(f, &t_functions, tf_next) { 307 if (f->tf_fb == blk) { 308 rblk = blk; 309 if (s) { 310 *s = f; 311 } 312 break; 313 } 314 } 315 return (rblk); 316 } 317 318 struct tcp_function_block * 319 find_and_ref_tcp_functions(struct tcp_function_set *fs) 320 { 321 struct tcp_function_block *blk; 322 323 rw_rlock(&tcp_function_lock); 324 blk = find_tcp_functions_locked(fs); 325 if (blk) 326 refcount_acquire(&blk->tfb_refcnt); 327 rw_runlock(&tcp_function_lock); 328 return(blk); 329 } 330 331 struct tcp_function_block * 332 find_and_ref_tcp_fb(struct tcp_function_block *blk) 333 { 334 struct tcp_function_block *rblk; 335 336 rw_rlock(&tcp_function_lock); 337 rblk = find_tcp_fb_locked(blk, NULL); 338 if (rblk) 339 refcount_acquire(&rblk->tfb_refcnt); 340 rw_runlock(&tcp_function_lock); 341 return(rblk); 342 } 343 344 345 static int 346 sysctl_net_inet_default_tcp_functions(SYSCTL_HANDLER_ARGS) 347 { 348 int error=ENOENT; 349 struct tcp_function_set fs; 350 struct tcp_function_block *blk; 351 352 memset(&fs, 0, sizeof(fs)); 353 rw_rlock(&tcp_function_lock); 354 blk = find_tcp_fb_locked(tcp_func_set_ptr, NULL); 355 if (blk) { 356 /* Found him */ 357 strcpy(fs.function_set_name, blk->tfb_tcp_block_name); 358 fs.pcbcnt = blk->tfb_refcnt; 359 } 360 rw_runlock(&tcp_function_lock); 361 error = sysctl_handle_string(oidp, fs.function_set_name, 362 sizeof(fs.function_set_name), req); 363 364 /* Check for error or no change */ 365 if (error != 0 || req->newptr == NULL) 366 return(error); 367 368 rw_wlock(&tcp_function_lock); 369 blk = find_tcp_functions_locked(&fs); 370 if ((blk == NULL) || 371 (blk->tfb_flags & TCP_FUNC_BEING_REMOVED)) { 372 error = ENOENT; 373 goto done; 374 } 375 tcp_func_set_ptr = blk; 376 done: 377 rw_wunlock(&tcp_function_lock); 378 return (error); 379 } 380 381 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, functions_default, 382 CTLTYPE_STRING | CTLFLAG_RW, 383 NULL, 0, sysctl_net_inet_default_tcp_functions, "A", 384 "Set/get the default TCP functions"); 385 386 static int 387 sysctl_net_inet_list_available(SYSCTL_HANDLER_ARGS) 388 { 389 int error, cnt, linesz; 390 struct tcp_function *f; 391 char *buffer, *cp; 392 size_t bufsz, outsz; 393 394 cnt = 0; 395 rw_rlock(&tcp_function_lock); 396 TAILQ_FOREACH(f, &t_functions, tf_next) { 397 cnt++; 398 } 399 rw_runlock(&tcp_function_lock); 400 401 bufsz = (cnt+2) * (TCP_FUNCTION_NAME_LEN_MAX + 12) + 1; 402 buffer = malloc(bufsz, M_TEMP, M_WAITOK); 403 404 error = 0; 405 cp = buffer; 406 407 linesz = snprintf(cp, bufsz, "\n%-32s%c %s\n", "Stack", 'D', "PCB count"); 408 cp += linesz; 409 bufsz -= linesz; 410 outsz = linesz; 411 412 rw_rlock(&tcp_function_lock); 413 TAILQ_FOREACH(f, &t_functions, tf_next) { 414 linesz = snprintf(cp, bufsz, "%-32s%c %u\n", 415 f->tf_fb->tfb_tcp_block_name, 416 (f->tf_fb == tcp_func_set_ptr) ? '*' : ' ', 417 f->tf_fb->tfb_refcnt); 418 if (linesz >= bufsz) { 419 error = EOVERFLOW; 420 break; 421 } 422 cp += linesz; 423 bufsz -= linesz; 424 outsz += linesz; 425 } 426 rw_runlock(&tcp_function_lock); 427 if (error == 0) 428 error = sysctl_handle_string(oidp, buffer, outsz + 1, req); 429 free(buffer, M_TEMP); 430 return (error); 431 } 432 433 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, functions_available, 434 CTLTYPE_STRING|CTLFLAG_RD, 435 NULL, 0, sysctl_net_inet_list_available, "A", 436 "list available TCP Function sets"); 437 438 /* 439 * Target size of TCP PCB hash tables. Must be a power of two. 440 * 441 * Note that this can be overridden by the kernel environment 442 * variable net.inet.tcp.tcbhashsize 443 */ 444 #ifndef TCBHASHSIZE 445 #define TCBHASHSIZE 0 446 #endif 447 448 /* 449 * XXX 450 * Callouts should be moved into struct tcp directly. They are currently 451 * separate because the tcpcb structure is exported to userland for sysctl 452 * parsing purposes, which do not know about callouts. 453 */ 454 struct tcpcb_mem { 455 struct tcpcb tcb; 456 struct tcp_timer tt; 457 struct cc_var ccv; 458 #ifdef TCP_HHOOK 459 struct osd osd; 460 #endif 461 }; 462 463 static VNET_DEFINE(uma_zone_t, tcpcb_zone); 464 #define V_tcpcb_zone VNET(tcpcb_zone) 465 466 MALLOC_DEFINE(M_TCPLOG, "tcplog", "TCP address and flags print buffers"); 467 MALLOC_DEFINE(M_TCPFUNCTIONS, "tcpfunc", "TCP function set memory"); 468 469 static struct mtx isn_mtx; 470 471 #define ISN_LOCK_INIT() mtx_init(&isn_mtx, "isn_mtx", NULL, MTX_DEF) 472 #define ISN_LOCK() mtx_lock(&isn_mtx) 473 #define ISN_UNLOCK() mtx_unlock(&isn_mtx) 474 475 /* 476 * TCP initialization. 477 */ 478 static void 479 tcp_zone_change(void *tag) 480 { 481 482 uma_zone_set_max(V_tcbinfo.ipi_zone, maxsockets); 483 uma_zone_set_max(V_tcpcb_zone, maxsockets); 484 tcp_tw_zone_change(); 485 } 486 487 static int 488 tcp_inpcb_init(void *mem, int size, int flags) 489 { 490 struct inpcb *inp = mem; 491 492 INP_LOCK_INIT(inp, "inp", "tcpinp"); 493 return (0); 494 } 495 496 /* 497 * Take a value and get the next power of 2 that doesn't overflow. 498 * Used to size the tcp_inpcb hash buckets. 499 */ 500 static int 501 maketcp_hashsize(int size) 502 { 503 int hashsize; 504 505 /* 506 * auto tune. 507 * get the next power of 2 higher than maxsockets. 508 */ 509 hashsize = 1 << fls(size); 510 /* catch overflow, and just go one power of 2 smaller */ 511 if (hashsize < size) { 512 hashsize = 1 << (fls(size) - 1); 513 } 514 return (hashsize); 515 } 516 517 int 518 register_tcp_functions(struct tcp_function_block *blk, int wait) 519 { 520 struct tcp_function_block *lblk; 521 struct tcp_function *n; 522 struct tcp_function_set fs; 523 524 if (t_functions_inited == 0) { 525 init_tcp_functions(); 526 } 527 if ((blk->tfb_tcp_output == NULL) || 528 (blk->tfb_tcp_do_segment == NULL) || 529 (blk->tfb_tcp_ctloutput == NULL) || 530 (strlen(blk->tfb_tcp_block_name) == 0)) { 531 /* 532 * These functions are required and you 533 * need a name. 534 */ 535 return (EINVAL); 536 } 537 if (blk->tfb_tcp_timer_stop_all || 538 blk->tfb_tcp_timer_activate || 539 blk->tfb_tcp_timer_active || 540 blk->tfb_tcp_timer_stop) { 541 /* 542 * If you define one timer function you 543 * must have them all. 544 */ 545 if ((blk->tfb_tcp_timer_stop_all == NULL) || 546 (blk->tfb_tcp_timer_activate == NULL) || 547 (blk->tfb_tcp_timer_active == NULL) || 548 (blk->tfb_tcp_timer_stop == NULL)) { 549 return (EINVAL); 550 } 551 } 552 n = malloc(sizeof(struct tcp_function), M_TCPFUNCTIONS, wait); 553 if (n == NULL) { 554 return (ENOMEM); 555 } 556 n->tf_fb = blk; 557 strcpy(fs.function_set_name, blk->tfb_tcp_block_name); 558 rw_wlock(&tcp_function_lock); 559 lblk = find_tcp_functions_locked(&fs); 560 if (lblk) { 561 /* Duplicate name space not allowed */ 562 rw_wunlock(&tcp_function_lock); 563 free(n, M_TCPFUNCTIONS); 564 return (EALREADY); 565 } 566 refcount_init(&blk->tfb_refcnt, 0); 567 blk->tfb_flags = 0; 568 TAILQ_INSERT_TAIL(&t_functions, n, tf_next); 569 rw_wunlock(&tcp_function_lock); 570 return(0); 571 } 572 573 int 574 deregister_tcp_functions(struct tcp_function_block *blk) 575 { 576 struct tcp_function_block *lblk; 577 struct tcp_function *f; 578 int error=ENOENT; 579 580 if (strcmp(blk->tfb_tcp_block_name, "default") == 0) { 581 /* You can't un-register the default */ 582 return (EPERM); 583 } 584 rw_wlock(&tcp_function_lock); 585 if (blk == tcp_func_set_ptr) { 586 /* You can't free the current default */ 587 rw_wunlock(&tcp_function_lock); 588 return (EBUSY); 589 } 590 if (blk->tfb_refcnt) { 591 /* Still tcb attached, mark it. */ 592 blk->tfb_flags |= TCP_FUNC_BEING_REMOVED; 593 rw_wunlock(&tcp_function_lock); 594 return (EBUSY); 595 } 596 lblk = find_tcp_fb_locked(blk, &f); 597 if (lblk) { 598 /* Found */ 599 TAILQ_REMOVE(&t_functions, f, tf_next); 600 f->tf_fb = NULL; 601 free(f, M_TCPFUNCTIONS); 602 error = 0; 603 } 604 rw_wunlock(&tcp_function_lock); 605 return (error); 606 } 607 608 void 609 tcp_init(void) 610 { 611 const char *tcbhash_tuneable; 612 int hashsize; 613 614 tcbhash_tuneable = "net.inet.tcp.tcbhashsize"; 615 616 #ifdef TCP_HHOOK 617 if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN, 618 &V_tcp_hhh[HHOOK_TCP_EST_IN], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0) 619 printf("%s: WARNING: unable to register helper hook\n", __func__); 620 if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT, 621 &V_tcp_hhh[HHOOK_TCP_EST_OUT], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0) 622 printf("%s: WARNING: unable to register helper hook\n", __func__); 623 #endif 624 hashsize = TCBHASHSIZE; 625 TUNABLE_INT_FETCH(tcbhash_tuneable, &hashsize); 626 if (hashsize == 0) { 627 /* 628 * Auto tune the hash size based on maxsockets. 629 * A perfect hash would have a 1:1 mapping 630 * (hashsize = maxsockets) however it's been 631 * suggested that O(2) average is better. 632 */ 633 hashsize = maketcp_hashsize(maxsockets / 4); 634 /* 635 * Our historical default is 512, 636 * do not autotune lower than this. 637 */ 638 if (hashsize < 512) 639 hashsize = 512; 640 if (bootverbose && IS_DEFAULT_VNET(curvnet)) 641 printf("%s: %s auto tuned to %d\n", __func__, 642 tcbhash_tuneable, hashsize); 643 } 644 /* 645 * We require a hashsize to be a power of two. 646 * Previously if it was not a power of two we would just reset it 647 * back to 512, which could be a nasty surprise if you did not notice 648 * the error message. 649 * Instead what we do is clip it to the closest power of two lower 650 * than the specified hash value. 651 */ 652 if (!powerof2(hashsize)) { 653 int oldhashsize = hashsize; 654 655 hashsize = maketcp_hashsize(hashsize); 656 /* prevent absurdly low value */ 657 if (hashsize < 16) 658 hashsize = 16; 659 printf("%s: WARNING: TCB hash size not a power of 2, " 660 "clipped from %d to %d.\n", __func__, oldhashsize, 661 hashsize); 662 } 663 in_pcbinfo_init(&V_tcbinfo, "tcp", &V_tcb, hashsize, hashsize, 664 "tcp_inpcb", tcp_inpcb_init, NULL, 0, IPI_HASHFIELDS_4TUPLE); 665 666 /* 667 * These have to be type stable for the benefit of the timers. 668 */ 669 V_tcpcb_zone = uma_zcreate("tcpcb", sizeof(struct tcpcb_mem), 670 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 671 uma_zone_set_max(V_tcpcb_zone, maxsockets); 672 uma_zone_set_warning(V_tcpcb_zone, "kern.ipc.maxsockets limit reached"); 673 674 tcp_tw_init(); 675 syncache_init(); 676 tcp_hc_init(); 677 678 TUNABLE_INT_FETCH("net.inet.tcp.sack.enable", &V_tcp_do_sack); 679 V_sack_hole_zone = uma_zcreate("sackhole", sizeof(struct sackhole), 680 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 681 682 /* Skip initialization of globals for non-default instances. */ 683 if (!IS_DEFAULT_VNET(curvnet)) 684 return; 685 686 tcp_reass_global_init(); 687 688 /* XXX virtualize those bellow? */ 689 tcp_delacktime = TCPTV_DELACK; 690 tcp_keepinit = TCPTV_KEEP_INIT; 691 tcp_keepidle = TCPTV_KEEP_IDLE; 692 tcp_keepintvl = TCPTV_KEEPINTVL; 693 tcp_maxpersistidle = TCPTV_KEEP_IDLE; 694 tcp_msl = TCPTV_MSL; 695 tcp_rexmit_min = TCPTV_MIN; 696 if (tcp_rexmit_min < 1) 697 tcp_rexmit_min = 1; 698 tcp_persmin = TCPTV_PERSMIN; 699 tcp_persmax = TCPTV_PERSMAX; 700 tcp_rexmit_slop = TCPTV_CPU_VAR; 701 tcp_finwait2_timeout = TCPTV_FINWAIT2_TIMEOUT; 702 tcp_tcbhashsize = hashsize; 703 /* Setup the tcp function block list */ 704 init_tcp_functions(); 705 register_tcp_functions(&tcp_def_funcblk, M_WAITOK); 706 707 if (tcp_soreceive_stream) { 708 #ifdef INET 709 tcp_usrreqs.pru_soreceive = soreceive_stream; 710 #endif 711 #ifdef INET6 712 tcp6_usrreqs.pru_soreceive = soreceive_stream; 713 #endif /* INET6 */ 714 } 715 716 #ifdef INET6 717 #define TCP_MINPROTOHDR (sizeof(struct ip6_hdr) + sizeof(struct tcphdr)) 718 #else /* INET6 */ 719 #define TCP_MINPROTOHDR (sizeof(struct tcpiphdr)) 720 #endif /* INET6 */ 721 if (max_protohdr < TCP_MINPROTOHDR) 722 max_protohdr = TCP_MINPROTOHDR; 723 if (max_linkhdr + TCP_MINPROTOHDR > MHLEN) 724 panic("tcp_init"); 725 #undef TCP_MINPROTOHDR 726 727 ISN_LOCK_INIT(); 728 EVENTHANDLER_REGISTER(shutdown_pre_sync, tcp_fini, NULL, 729 SHUTDOWN_PRI_DEFAULT); 730 EVENTHANDLER_REGISTER(maxsockets_change, tcp_zone_change, NULL, 731 EVENTHANDLER_PRI_ANY); 732 #ifdef TCPPCAP 733 tcp_pcap_init(); 734 #endif 735 736 #ifdef TCP_RFC7413 737 tcp_fastopen_init(); 738 #endif 739 } 740 741 #ifdef VIMAGE 742 static void 743 tcp_destroy(void *unused __unused) 744 { 745 int error, n; 746 747 /* 748 * All our processes are gone, all our sockets should be cleaned 749 * up, which means, we should be past the tcp_discardcb() calls. 750 * Sleep to let all tcpcb timers really disappear and cleanup. 751 */ 752 for (;;) { 753 INP_LIST_RLOCK(&V_tcbinfo); 754 n = V_tcbinfo.ipi_count; 755 INP_LIST_RUNLOCK(&V_tcbinfo); 756 if (n == 0) 757 break; 758 pause("tcpdes", hz / 10); 759 } 760 tcp_hc_destroy(); 761 syncache_destroy(); 762 tcp_tw_destroy(); 763 in_pcbinfo_destroy(&V_tcbinfo); 764 /* tcp_discardcb() clears the sack_holes up. */ 765 uma_zdestroy(V_sack_hole_zone); 766 uma_zdestroy(V_tcpcb_zone); 767 768 #ifdef TCP_RFC7413 769 /* 770 * Cannot free the zone until all tcpcbs are released as we attach 771 * the allocations to them. 772 */ 773 tcp_fastopen_destroy(); 774 #endif 775 776 #ifdef TCP_HHOOK 777 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_IN]); 778 if (error != 0) { 779 printf("%s: WARNING: unable to deregister helper hook " 780 "type=%d, id=%d: error %d returned\n", __func__, 781 HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN, error); 782 } 783 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_OUT]); 784 if (error != 0) { 785 printf("%s: WARNING: unable to deregister helper hook " 786 "type=%d, id=%d: error %d returned\n", __func__, 787 HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT, error); 788 } 789 #endif 790 } 791 VNET_SYSUNINIT(tcp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, tcp_destroy, NULL); 792 #endif 793 794 void 795 tcp_fini(void *xtp) 796 { 797 798 } 799 800 /* 801 * Fill in the IP and TCP headers for an outgoing packet, given the tcpcb. 802 * tcp_template used to store this data in mbufs, but we now recopy it out 803 * of the tcpcb each time to conserve mbufs. 804 */ 805 void 806 tcpip_fillheaders(struct inpcb *inp, void *ip_ptr, void *tcp_ptr) 807 { 808 struct tcphdr *th = (struct tcphdr *)tcp_ptr; 809 810 INP_WLOCK_ASSERT(inp); 811 812 #ifdef INET6 813 if ((inp->inp_vflag & INP_IPV6) != 0) { 814 struct ip6_hdr *ip6; 815 816 ip6 = (struct ip6_hdr *)ip_ptr; 817 ip6->ip6_flow = (ip6->ip6_flow & ~IPV6_FLOWINFO_MASK) | 818 (inp->inp_flow & IPV6_FLOWINFO_MASK); 819 ip6->ip6_vfc = (ip6->ip6_vfc & ~IPV6_VERSION_MASK) | 820 (IPV6_VERSION & IPV6_VERSION_MASK); 821 ip6->ip6_nxt = IPPROTO_TCP; 822 ip6->ip6_plen = htons(sizeof(struct tcphdr)); 823 ip6->ip6_src = inp->in6p_laddr; 824 ip6->ip6_dst = inp->in6p_faddr; 825 } 826 #endif /* INET6 */ 827 #if defined(INET6) && defined(INET) 828 else 829 #endif 830 #ifdef INET 831 { 832 struct ip *ip; 833 834 ip = (struct ip *)ip_ptr; 835 ip->ip_v = IPVERSION; 836 ip->ip_hl = 5; 837 ip->ip_tos = inp->inp_ip_tos; 838 ip->ip_len = 0; 839 ip->ip_id = 0; 840 ip->ip_off = 0; 841 ip->ip_ttl = inp->inp_ip_ttl; 842 ip->ip_sum = 0; 843 ip->ip_p = IPPROTO_TCP; 844 ip->ip_src = inp->inp_laddr; 845 ip->ip_dst = inp->inp_faddr; 846 } 847 #endif /* INET */ 848 th->th_sport = inp->inp_lport; 849 th->th_dport = inp->inp_fport; 850 th->th_seq = 0; 851 th->th_ack = 0; 852 th->th_x2 = 0; 853 th->th_off = 5; 854 th->th_flags = 0; 855 th->th_win = 0; 856 th->th_urp = 0; 857 th->th_sum = 0; /* in_pseudo() is called later for ipv4 */ 858 } 859 860 /* 861 * Create template to be used to send tcp packets on a connection. 862 * Allocates an mbuf and fills in a skeletal tcp/ip header. The only 863 * use for this function is in keepalives, which use tcp_respond. 864 */ 865 struct tcptemp * 866 tcpip_maketemplate(struct inpcb *inp) 867 { 868 struct tcptemp *t; 869 870 t = malloc(sizeof(*t), M_TEMP, M_NOWAIT); 871 if (t == NULL) 872 return (NULL); 873 tcpip_fillheaders(inp, (void *)&t->tt_ipgen, (void *)&t->tt_t); 874 return (t); 875 } 876 877 /* 878 * Send a single message to the TCP at address specified by 879 * the given TCP/IP header. If m == NULL, then we make a copy 880 * of the tcpiphdr at th and send directly to the addressed host. 881 * This is used to force keep alive messages out using the TCP 882 * template for a connection. If flags are given then we send 883 * a message back to the TCP which originated the segment th, 884 * and discard the mbuf containing it and any other attached mbufs. 885 * 886 * In any case the ack and sequence number of the transmitted 887 * segment are as specified by the parameters. 888 * 889 * NOTE: If m != NULL, then th must point to *inside* the mbuf. 890 */ 891 void 892 tcp_respond(struct tcpcb *tp, void *ipgen, struct tcphdr *th, struct mbuf *m, 893 tcp_seq ack, tcp_seq seq, int flags) 894 { 895 struct tcpopt to; 896 struct inpcb *inp; 897 struct ip *ip; 898 struct mbuf *optm; 899 struct tcphdr *nth; 900 u_char *optp; 901 #ifdef INET6 902 struct ip6_hdr *ip6; 903 int isipv6; 904 #endif /* INET6 */ 905 int optlen, tlen, win; 906 bool incl_opts; 907 908 KASSERT(tp != NULL || m != NULL, ("tcp_respond: tp and m both NULL")); 909 910 #ifdef INET6 911 isipv6 = ((struct ip *)ipgen)->ip_v == (IPV6_VERSION >> 4); 912 ip6 = ipgen; 913 #endif /* INET6 */ 914 ip = ipgen; 915 916 if (tp != NULL) { 917 inp = tp->t_inpcb; 918 KASSERT(inp != NULL, ("tcp control block w/o inpcb")); 919 INP_WLOCK_ASSERT(inp); 920 } else 921 inp = NULL; 922 923 incl_opts = false; 924 win = 0; 925 if (tp != NULL) { 926 if (!(flags & TH_RST)) { 927 win = sbspace(&inp->inp_socket->so_rcv); 928 if (win > TCP_MAXWIN << tp->rcv_scale) 929 win = TCP_MAXWIN << tp->rcv_scale; 930 } 931 if ((tp->t_flags & TF_NOOPT) == 0) 932 incl_opts = true; 933 } 934 if (m == NULL) { 935 m = m_gethdr(M_NOWAIT, MT_DATA); 936 if (m == NULL) 937 return; 938 m->m_data += max_linkhdr; 939 #ifdef INET6 940 if (isipv6) { 941 bcopy((caddr_t)ip6, mtod(m, caddr_t), 942 sizeof(struct ip6_hdr)); 943 ip6 = mtod(m, struct ip6_hdr *); 944 nth = (struct tcphdr *)(ip6 + 1); 945 } else 946 #endif /* INET6 */ 947 { 948 bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip)); 949 ip = mtod(m, struct ip *); 950 nth = (struct tcphdr *)(ip + 1); 951 } 952 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr)); 953 flags = TH_ACK; 954 } else if (!M_WRITABLE(m)) { 955 struct mbuf *n; 956 957 /* Can't reuse 'm', allocate a new mbuf. */ 958 n = m_gethdr(M_NOWAIT, MT_DATA); 959 if (n == NULL) { 960 m_freem(m); 961 return; 962 } 963 964 if (!m_dup_pkthdr(n, m, M_NOWAIT)) { 965 m_freem(m); 966 m_freem(n); 967 return; 968 } 969 970 n->m_data += max_linkhdr; 971 /* m_len is set later */ 972 #define xchg(a,b,type) { type t; t=a; a=b; b=t; } 973 #ifdef INET6 974 if (isipv6) { 975 bcopy((caddr_t)ip6, mtod(n, caddr_t), 976 sizeof(struct ip6_hdr)); 977 ip6 = mtod(n, struct ip6_hdr *); 978 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); 979 nth = (struct tcphdr *)(ip6 + 1); 980 } else 981 #endif /* INET6 */ 982 { 983 bcopy((caddr_t)ip, mtod(n, caddr_t), sizeof(struct ip)); 984 ip = mtod(n, struct ip *); 985 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t); 986 nth = (struct tcphdr *)(ip + 1); 987 } 988 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr)); 989 xchg(nth->th_dport, nth->th_sport, uint16_t); 990 th = nth; 991 m_freem(m); 992 m = n; 993 } else { 994 /* 995 * reuse the mbuf. 996 * XXX MRT We inherit the FIB, which is lucky. 997 */ 998 m_freem(m->m_next); 999 m->m_next = NULL; 1000 m->m_data = (caddr_t)ipgen; 1001 /* m_len is set later */ 1002 #ifdef INET6 1003 if (isipv6) { 1004 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); 1005 nth = (struct tcphdr *)(ip6 + 1); 1006 } else 1007 #endif /* INET6 */ 1008 { 1009 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t); 1010 nth = (struct tcphdr *)(ip + 1); 1011 } 1012 if (th != nth) { 1013 /* 1014 * this is usually a case when an extension header 1015 * exists between the IPv6 header and the 1016 * TCP header. 1017 */ 1018 nth->th_sport = th->th_sport; 1019 nth->th_dport = th->th_dport; 1020 } 1021 xchg(nth->th_dport, nth->th_sport, uint16_t); 1022 #undef xchg 1023 } 1024 tlen = 0; 1025 #ifdef INET6 1026 if (isipv6) 1027 tlen = sizeof (struct ip6_hdr) + sizeof (struct tcphdr); 1028 #endif 1029 #if defined(INET) && defined(INET6) 1030 else 1031 #endif 1032 #ifdef INET 1033 tlen = sizeof (struct tcpiphdr); 1034 #endif 1035 #ifdef INVARIANTS 1036 m->m_len = 0; 1037 KASSERT(M_TRAILINGSPACE(m) >= tlen, 1038 ("Not enough trailing space for message (m=%p, need=%d, have=%ld)", 1039 m, tlen, (long)M_TRAILINGSPACE(m))); 1040 #endif 1041 m->m_len = tlen; 1042 to.to_flags = 0; 1043 if (incl_opts) { 1044 /* Make sure we have room. */ 1045 if (M_TRAILINGSPACE(m) < TCP_MAXOLEN) { 1046 m->m_next = m_get(M_NOWAIT, MT_DATA); 1047 if (m->m_next) { 1048 optp = mtod(m->m_next, u_char *); 1049 optm = m->m_next; 1050 } else 1051 incl_opts = false; 1052 } else { 1053 optp = (u_char *) (nth + 1); 1054 optm = m; 1055 } 1056 } 1057 if (incl_opts) { 1058 /* Timestamps. */ 1059 if (tp->t_flags & TF_RCVD_TSTMP) { 1060 to.to_tsval = tcp_ts_getticks() + tp->ts_offset; 1061 to.to_tsecr = tp->ts_recent; 1062 to.to_flags |= TOF_TS; 1063 } 1064 #ifdef TCP_SIGNATURE 1065 /* TCP-MD5 (RFC2385). */ 1066 if (tp->t_flags & TF_SIGNATURE) 1067 to.to_flags |= TOF_SIGNATURE; 1068 #endif 1069 1070 /* Add the options. */ 1071 tlen += optlen = tcp_addoptions(&to, optp); 1072 1073 /* Update m_len in the correct mbuf. */ 1074 optm->m_len += optlen; 1075 } else 1076 optlen = 0; 1077 #ifdef INET6 1078 if (isipv6) { 1079 ip6->ip6_flow = 0; 1080 ip6->ip6_vfc = IPV6_VERSION; 1081 ip6->ip6_nxt = IPPROTO_TCP; 1082 ip6->ip6_plen = htons(tlen - sizeof(*ip6)); 1083 } 1084 #endif 1085 #if defined(INET) && defined(INET6) 1086 else 1087 #endif 1088 #ifdef INET 1089 { 1090 ip->ip_len = htons(tlen); 1091 ip->ip_ttl = V_ip_defttl; 1092 if (V_path_mtu_discovery) 1093 ip->ip_off |= htons(IP_DF); 1094 } 1095 #endif 1096 m->m_pkthdr.len = tlen; 1097 m->m_pkthdr.rcvif = NULL; 1098 #ifdef MAC 1099 if (inp != NULL) { 1100 /* 1101 * Packet is associated with a socket, so allow the 1102 * label of the response to reflect the socket label. 1103 */ 1104 INP_WLOCK_ASSERT(inp); 1105 mac_inpcb_create_mbuf(inp, m); 1106 } else { 1107 /* 1108 * Packet is not associated with a socket, so possibly 1109 * update the label in place. 1110 */ 1111 mac_netinet_tcp_reply(m); 1112 } 1113 #endif 1114 nth->th_seq = htonl(seq); 1115 nth->th_ack = htonl(ack); 1116 nth->th_x2 = 0; 1117 nth->th_off = (sizeof (struct tcphdr) + optlen) >> 2; 1118 nth->th_flags = flags; 1119 if (tp != NULL) 1120 nth->th_win = htons((u_short) (win >> tp->rcv_scale)); 1121 else 1122 nth->th_win = htons((u_short)win); 1123 nth->th_urp = 0; 1124 1125 #ifdef TCP_SIGNATURE 1126 if (to.to_flags & TOF_SIGNATURE) { 1127 tcp_signature_compute(m, 0, 0, optlen, to.to_signature, 1128 IPSEC_DIR_OUTBOUND); 1129 } 1130 #endif 1131 1132 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); 1133 #ifdef INET6 1134 if (isipv6) { 1135 m->m_pkthdr.csum_flags = CSUM_TCP_IPV6; 1136 nth->th_sum = in6_cksum_pseudo(ip6, 1137 tlen - sizeof(struct ip6_hdr), IPPROTO_TCP, 0); 1138 ip6->ip6_hlim = in6_selecthlim(tp != NULL ? tp->t_inpcb : 1139 NULL, NULL); 1140 } 1141 #endif /* INET6 */ 1142 #if defined(INET6) && defined(INET) 1143 else 1144 #endif 1145 #ifdef INET 1146 { 1147 m->m_pkthdr.csum_flags = CSUM_TCP; 1148 nth->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, 1149 htons((u_short)(tlen - sizeof(struct ip) + ip->ip_p))); 1150 } 1151 #endif /* INET */ 1152 #ifdef TCPDEBUG 1153 if (tp == NULL || (inp->inp_socket->so_options & SO_DEBUG)) 1154 tcp_trace(TA_OUTPUT, 0, tp, mtod(m, void *), th, 0); 1155 #endif 1156 TCP_PROBE3(debug__output, tp, th, mtod(m, const char *)); 1157 if (flags & TH_RST) 1158 TCP_PROBE5(accept__refused, NULL, NULL, mtod(m, const char *), 1159 tp, nth); 1160 1161 TCP_PROBE5(send, NULL, tp, mtod(m, const char *), tp, nth); 1162 #ifdef INET6 1163 if (isipv6) 1164 (void) ip6_output(m, NULL, NULL, 0, NULL, NULL, inp); 1165 #endif /* INET6 */ 1166 #if defined(INET) && defined(INET6) 1167 else 1168 #endif 1169 #ifdef INET 1170 (void) ip_output(m, NULL, NULL, 0, NULL, inp); 1171 #endif 1172 } 1173 1174 /* 1175 * Create a new TCP control block, making an 1176 * empty reassembly queue and hooking it to the argument 1177 * protocol control block. The `inp' parameter must have 1178 * come from the zone allocator set up in tcp_init(). 1179 */ 1180 struct tcpcb * 1181 tcp_newtcpcb(struct inpcb *inp) 1182 { 1183 struct tcpcb_mem *tm; 1184 struct tcpcb *tp; 1185 #ifdef INET6 1186 int isipv6 = (inp->inp_vflag & INP_IPV6) != 0; 1187 #endif /* INET6 */ 1188 1189 tm = uma_zalloc(V_tcpcb_zone, M_NOWAIT | M_ZERO); 1190 if (tm == NULL) 1191 return (NULL); 1192 tp = &tm->tcb; 1193 1194 /* Initialise cc_var struct for this tcpcb. */ 1195 tp->ccv = &tm->ccv; 1196 tp->ccv->type = IPPROTO_TCP; 1197 tp->ccv->ccvc.tcp = tp; 1198 rw_rlock(&tcp_function_lock); 1199 tp->t_fb = tcp_func_set_ptr; 1200 refcount_acquire(&tp->t_fb->tfb_refcnt); 1201 rw_runlock(&tcp_function_lock); 1202 /* 1203 * Use the current system default CC algorithm. 1204 */ 1205 CC_LIST_RLOCK(); 1206 KASSERT(!STAILQ_EMPTY(&cc_list), ("cc_list is empty!")); 1207 CC_ALGO(tp) = CC_DEFAULT(); 1208 CC_LIST_RUNLOCK(); 1209 1210 if (CC_ALGO(tp)->cb_init != NULL) 1211 if (CC_ALGO(tp)->cb_init(tp->ccv) > 0) { 1212 if (tp->t_fb->tfb_tcp_fb_fini) 1213 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); 1214 refcount_release(&tp->t_fb->tfb_refcnt); 1215 uma_zfree(V_tcpcb_zone, tm); 1216 return (NULL); 1217 } 1218 1219 #ifdef TCP_HHOOK 1220 tp->osd = &tm->osd; 1221 if (khelp_init_osd(HELPER_CLASS_TCP, tp->osd)) { 1222 if (tp->t_fb->tfb_tcp_fb_fini) 1223 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); 1224 refcount_release(&tp->t_fb->tfb_refcnt); 1225 uma_zfree(V_tcpcb_zone, tm); 1226 return (NULL); 1227 } 1228 #endif 1229 1230 #ifdef VIMAGE 1231 tp->t_vnet = inp->inp_vnet; 1232 #endif 1233 tp->t_timers = &tm->tt; 1234 /* LIST_INIT(&tp->t_segq); */ /* XXX covered by M_ZERO */ 1235 tp->t_maxseg = 1236 #ifdef INET6 1237 isipv6 ? V_tcp_v6mssdflt : 1238 #endif /* INET6 */ 1239 V_tcp_mssdflt; 1240 1241 /* Set up our timeouts. */ 1242 callout_init(&tp->t_timers->tt_rexmt, 1); 1243 callout_init(&tp->t_timers->tt_persist, 1); 1244 callout_init(&tp->t_timers->tt_keep, 1); 1245 callout_init(&tp->t_timers->tt_2msl, 1); 1246 callout_init(&tp->t_timers->tt_delack, 1); 1247 1248 if (V_tcp_do_rfc1323) 1249 tp->t_flags = (TF_REQ_SCALE|TF_REQ_TSTMP); 1250 if (V_tcp_do_sack) 1251 tp->t_flags |= TF_SACK_PERMIT; 1252 TAILQ_INIT(&tp->snd_holes); 1253 /* 1254 * The tcpcb will hold a reference on its inpcb until tcp_discardcb() 1255 * is called. 1256 */ 1257 in_pcbref(inp); /* Reference for tcpcb */ 1258 tp->t_inpcb = inp; 1259 1260 /* 1261 * Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no 1262 * rtt estimate. Set rttvar so that srtt + 4 * rttvar gives 1263 * reasonable initial retransmit time. 1264 */ 1265 tp->t_srtt = TCPTV_SRTTBASE; 1266 tp->t_rttvar = ((TCPTV_RTOBASE - TCPTV_SRTTBASE) << TCP_RTTVAR_SHIFT) / 4; 1267 tp->t_rttmin = tcp_rexmit_min; 1268 tp->t_rxtcur = TCPTV_RTOBASE; 1269 tp->snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT; 1270 tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT; 1271 tp->t_rcvtime = ticks; 1272 /* 1273 * IPv4 TTL initialization is necessary for an IPv6 socket as well, 1274 * because the socket may be bound to an IPv6 wildcard address, 1275 * which may match an IPv4-mapped IPv6 address. 1276 */ 1277 inp->inp_ip_ttl = V_ip_defttl; 1278 inp->inp_ppcb = tp; 1279 #ifdef TCPPCAP 1280 /* 1281 * Init the TCP PCAP queues. 1282 */ 1283 tcp_pcap_tcpcb_init(tp); 1284 #endif 1285 if (tp->t_fb->tfb_tcp_fb_init) { 1286 (*tp->t_fb->tfb_tcp_fb_init)(tp); 1287 } 1288 return (tp); /* XXX */ 1289 } 1290 1291 /* 1292 * Switch the congestion control algorithm back to NewReno for any active 1293 * control blocks using an algorithm which is about to go away. 1294 * This ensures the CC framework can allow the unload to proceed without leaving 1295 * any dangling pointers which would trigger a panic. 1296 * Returning non-zero would inform the CC framework that something went wrong 1297 * and it would be unsafe to allow the unload to proceed. However, there is no 1298 * way for this to occur with this implementation so we always return zero. 1299 */ 1300 int 1301 tcp_ccalgounload(struct cc_algo *unload_algo) 1302 { 1303 struct cc_algo *tmpalgo; 1304 struct inpcb *inp; 1305 struct tcpcb *tp; 1306 VNET_ITERATOR_DECL(vnet_iter); 1307 1308 /* 1309 * Check all active control blocks across all network stacks and change 1310 * any that are using "unload_algo" back to NewReno. If "unload_algo" 1311 * requires cleanup code to be run, call it. 1312 */ 1313 VNET_LIST_RLOCK(); 1314 VNET_FOREACH(vnet_iter) { 1315 CURVNET_SET(vnet_iter); 1316 INP_INFO_WLOCK(&V_tcbinfo); 1317 /* 1318 * New connections already part way through being initialised 1319 * with the CC algo we're removing will not race with this code 1320 * because the INP_INFO_WLOCK is held during initialisation. We 1321 * therefore don't enter the loop below until the connection 1322 * list has stabilised. 1323 */ 1324 LIST_FOREACH(inp, &V_tcb, inp_list) { 1325 INP_WLOCK(inp); 1326 /* Important to skip tcptw structs. */ 1327 if (!(inp->inp_flags & INP_TIMEWAIT) && 1328 (tp = intotcpcb(inp)) != NULL) { 1329 /* 1330 * By holding INP_WLOCK here, we are assured 1331 * that the connection is not currently 1332 * executing inside the CC module's functions 1333 * i.e. it is safe to make the switch back to 1334 * NewReno. 1335 */ 1336 if (CC_ALGO(tp) == unload_algo) { 1337 tmpalgo = CC_ALGO(tp); 1338 /* NewReno does not require any init. */ 1339 CC_ALGO(tp) = &newreno_cc_algo; 1340 if (tmpalgo->cb_destroy != NULL) 1341 tmpalgo->cb_destroy(tp->ccv); 1342 } 1343 } 1344 INP_WUNLOCK(inp); 1345 } 1346 INP_INFO_WUNLOCK(&V_tcbinfo); 1347 CURVNET_RESTORE(); 1348 } 1349 VNET_LIST_RUNLOCK(); 1350 1351 return (0); 1352 } 1353 1354 /* 1355 * Drop a TCP connection, reporting 1356 * the specified error. If connection is synchronized, 1357 * then send a RST to peer. 1358 */ 1359 struct tcpcb * 1360 tcp_drop(struct tcpcb *tp, int errno) 1361 { 1362 struct socket *so = tp->t_inpcb->inp_socket; 1363 1364 INP_INFO_LOCK_ASSERT(&V_tcbinfo); 1365 INP_WLOCK_ASSERT(tp->t_inpcb); 1366 1367 if (TCPS_HAVERCVDSYN(tp->t_state)) { 1368 tcp_state_change(tp, TCPS_CLOSED); 1369 (void) tp->t_fb->tfb_tcp_output(tp); 1370 TCPSTAT_INC(tcps_drops); 1371 } else 1372 TCPSTAT_INC(tcps_conndrops); 1373 if (errno == ETIMEDOUT && tp->t_softerror) 1374 errno = tp->t_softerror; 1375 so->so_error = errno; 1376 return (tcp_close(tp)); 1377 } 1378 1379 void 1380 tcp_discardcb(struct tcpcb *tp) 1381 { 1382 struct inpcb *inp = tp->t_inpcb; 1383 struct socket *so = inp->inp_socket; 1384 #ifdef INET6 1385 int isipv6 = (inp->inp_vflag & INP_IPV6) != 0; 1386 #endif /* INET6 */ 1387 int released; 1388 1389 INP_WLOCK_ASSERT(inp); 1390 1391 /* 1392 * Make sure that all of our timers are stopped before we delete the 1393 * PCB. 1394 * 1395 * If stopping a timer fails, we schedule a discard function in same 1396 * callout, and the last discard function called will take care of 1397 * deleting the tcpcb. 1398 */ 1399 tp->t_timers->tt_draincnt = 0; 1400 tcp_timer_stop(tp, TT_REXMT); 1401 tcp_timer_stop(tp, TT_PERSIST); 1402 tcp_timer_stop(tp, TT_KEEP); 1403 tcp_timer_stop(tp, TT_2MSL); 1404 tcp_timer_stop(tp, TT_DELACK); 1405 if (tp->t_fb->tfb_tcp_timer_stop_all) { 1406 /* 1407 * Call the stop-all function of the methods, 1408 * this function should call the tcp_timer_stop() 1409 * method with each of the function specific timeouts. 1410 * That stop will be called via the tfb_tcp_timer_stop() 1411 * which should use the async drain function of the 1412 * callout system (see tcp_var.h). 1413 */ 1414 tp->t_fb->tfb_tcp_timer_stop_all(tp); 1415 } 1416 1417 /* 1418 * If we got enough samples through the srtt filter, 1419 * save the rtt and rttvar in the routing entry. 1420 * 'Enough' is arbitrarily defined as 4 rtt samples. 1421 * 4 samples is enough for the srtt filter to converge 1422 * to within enough % of the correct value; fewer samples 1423 * and we could save a bogus rtt. The danger is not high 1424 * as tcp quickly recovers from everything. 1425 * XXX: Works very well but needs some more statistics! 1426 */ 1427 if (tp->t_rttupdated >= 4) { 1428 struct hc_metrics_lite metrics; 1429 uint32_t ssthresh; 1430 1431 bzero(&metrics, sizeof(metrics)); 1432 /* 1433 * Update the ssthresh always when the conditions below 1434 * are satisfied. This gives us better new start value 1435 * for the congestion avoidance for new connections. 1436 * ssthresh is only set if packet loss occurred on a session. 1437 * 1438 * XXXRW: 'so' may be NULL here, and/or socket buffer may be 1439 * being torn down. Ideally this code would not use 'so'. 1440 */ 1441 ssthresh = tp->snd_ssthresh; 1442 if (ssthresh != 0 && ssthresh < so->so_snd.sb_hiwat / 2) { 1443 /* 1444 * convert the limit from user data bytes to 1445 * packets then to packet data bytes. 1446 */ 1447 ssthresh = (ssthresh + tp->t_maxseg / 2) / tp->t_maxseg; 1448 if (ssthresh < 2) 1449 ssthresh = 2; 1450 ssthresh *= (tp->t_maxseg + 1451 #ifdef INET6 1452 (isipv6 ? sizeof (struct ip6_hdr) + 1453 sizeof (struct tcphdr) : 1454 #endif 1455 sizeof (struct tcpiphdr) 1456 #ifdef INET6 1457 ) 1458 #endif 1459 ); 1460 } else 1461 ssthresh = 0; 1462 metrics.rmx_ssthresh = ssthresh; 1463 1464 metrics.rmx_rtt = tp->t_srtt; 1465 metrics.rmx_rttvar = tp->t_rttvar; 1466 metrics.rmx_cwnd = tp->snd_cwnd; 1467 metrics.rmx_sendpipe = 0; 1468 metrics.rmx_recvpipe = 0; 1469 1470 tcp_hc_update(&inp->inp_inc, &metrics); 1471 } 1472 1473 /* free the reassembly queue, if any */ 1474 tcp_reass_flush(tp); 1475 1476 #ifdef TCP_OFFLOAD 1477 /* Disconnect offload device, if any. */ 1478 if (tp->t_flags & TF_TOE) 1479 tcp_offload_detach(tp); 1480 #endif 1481 1482 tcp_free_sackholes(tp); 1483 1484 #ifdef TCPPCAP 1485 /* Free the TCP PCAP queues. */ 1486 tcp_pcap_drain(&(tp->t_inpkts)); 1487 tcp_pcap_drain(&(tp->t_outpkts)); 1488 #endif 1489 1490 /* Allow the CC algorithm to clean up after itself. */ 1491 if (CC_ALGO(tp)->cb_destroy != NULL) 1492 CC_ALGO(tp)->cb_destroy(tp->ccv); 1493 1494 #ifdef TCP_HHOOK 1495 khelp_destroy_osd(tp->osd); 1496 #endif 1497 1498 CC_ALGO(tp) = NULL; 1499 inp->inp_ppcb = NULL; 1500 if (tp->t_timers->tt_draincnt == 0) { 1501 /* We own the last reference on tcpcb, let's free it. */ 1502 if (tp->t_fb->tfb_tcp_fb_fini) 1503 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); 1504 refcount_release(&tp->t_fb->tfb_refcnt); 1505 tp->t_inpcb = NULL; 1506 uma_zfree(V_tcpcb_zone, tp); 1507 released = in_pcbrele_wlocked(inp); 1508 KASSERT(!released, ("%s: inp %p should not have been released " 1509 "here", __func__, inp)); 1510 } 1511 } 1512 1513 void 1514 tcp_timer_discard(void *ptp) 1515 { 1516 struct inpcb *inp; 1517 struct tcpcb *tp; 1518 1519 tp = (struct tcpcb *)ptp; 1520 CURVNET_SET(tp->t_vnet); 1521 INP_INFO_RLOCK(&V_tcbinfo); 1522 inp = tp->t_inpcb; 1523 KASSERT(inp != NULL, ("%s: tp %p tp->t_inpcb == NULL", 1524 __func__, tp)); 1525 INP_WLOCK(inp); 1526 KASSERT((tp->t_timers->tt_flags & TT_STOPPED) != 0, 1527 ("%s: tcpcb has to be stopped here", __func__)); 1528 tp->t_timers->tt_draincnt--; 1529 if (tp->t_timers->tt_draincnt == 0) { 1530 /* We own the last reference on this tcpcb, let's free it. */ 1531 if (tp->t_fb->tfb_tcp_fb_fini) 1532 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); 1533 refcount_release(&tp->t_fb->tfb_refcnt); 1534 tp->t_inpcb = NULL; 1535 uma_zfree(V_tcpcb_zone, tp); 1536 if (in_pcbrele_wlocked(inp)) { 1537 INP_INFO_RUNLOCK(&V_tcbinfo); 1538 CURVNET_RESTORE(); 1539 return; 1540 } 1541 } 1542 INP_WUNLOCK(inp); 1543 INP_INFO_RUNLOCK(&V_tcbinfo); 1544 CURVNET_RESTORE(); 1545 } 1546 1547 /* 1548 * Attempt to close a TCP control block, marking it as dropped, and freeing 1549 * the socket if we hold the only reference. 1550 */ 1551 struct tcpcb * 1552 tcp_close(struct tcpcb *tp) 1553 { 1554 struct inpcb *inp = tp->t_inpcb; 1555 struct socket *so; 1556 1557 INP_INFO_LOCK_ASSERT(&V_tcbinfo); 1558 INP_WLOCK_ASSERT(inp); 1559 1560 #ifdef TCP_OFFLOAD 1561 if (tp->t_state == TCPS_LISTEN) 1562 tcp_offload_listen_stop(tp); 1563 #endif 1564 #ifdef TCP_RFC7413 1565 /* 1566 * This releases the TFO pending counter resource for TFO listen 1567 * sockets as well as passively-created TFO sockets that transition 1568 * from SYN_RECEIVED to CLOSED. 1569 */ 1570 if (tp->t_tfo_pending) { 1571 tcp_fastopen_decrement_counter(tp->t_tfo_pending); 1572 tp->t_tfo_pending = NULL; 1573 } 1574 #endif 1575 in_pcbdrop(inp); 1576 TCPSTAT_INC(tcps_closed); 1577 TCPSTATES_DEC(tp->t_state); 1578 KASSERT(inp->inp_socket != NULL, ("tcp_close: inp_socket NULL")); 1579 so = inp->inp_socket; 1580 soisdisconnected(so); 1581 if (inp->inp_flags & INP_SOCKREF) { 1582 KASSERT(so->so_state & SS_PROTOREF, 1583 ("tcp_close: !SS_PROTOREF")); 1584 inp->inp_flags &= ~INP_SOCKREF; 1585 INP_WUNLOCK(inp); 1586 ACCEPT_LOCK(); 1587 SOCK_LOCK(so); 1588 so->so_state &= ~SS_PROTOREF; 1589 sofree(so); 1590 return (NULL); 1591 } 1592 return (tp); 1593 } 1594 1595 void 1596 tcp_drain(void) 1597 { 1598 VNET_ITERATOR_DECL(vnet_iter); 1599 1600 if (!do_tcpdrain) 1601 return; 1602 1603 VNET_LIST_RLOCK_NOSLEEP(); 1604 VNET_FOREACH(vnet_iter) { 1605 CURVNET_SET(vnet_iter); 1606 struct inpcb *inpb; 1607 struct tcpcb *tcpb; 1608 1609 /* 1610 * Walk the tcpbs, if existing, and flush the reassembly queue, 1611 * if there is one... 1612 * XXX: The "Net/3" implementation doesn't imply that the TCP 1613 * reassembly queue should be flushed, but in a situation 1614 * where we're really low on mbufs, this is potentially 1615 * useful. 1616 */ 1617 INP_INFO_WLOCK(&V_tcbinfo); 1618 LIST_FOREACH(inpb, V_tcbinfo.ipi_listhead, inp_list) { 1619 if (inpb->inp_flags & INP_TIMEWAIT) 1620 continue; 1621 INP_WLOCK(inpb); 1622 if ((tcpb = intotcpcb(inpb)) != NULL) { 1623 tcp_reass_flush(tcpb); 1624 tcp_clean_sackreport(tcpb); 1625 #ifdef TCPPCAP 1626 if (tcp_pcap_aggressive_free) { 1627 /* Free the TCP PCAP queues. */ 1628 tcp_pcap_drain(&(tcpb->t_inpkts)); 1629 tcp_pcap_drain(&(tcpb->t_outpkts)); 1630 } 1631 #endif 1632 } 1633 INP_WUNLOCK(inpb); 1634 } 1635 INP_INFO_WUNLOCK(&V_tcbinfo); 1636 CURVNET_RESTORE(); 1637 } 1638 VNET_LIST_RUNLOCK_NOSLEEP(); 1639 } 1640 1641 /* 1642 * Notify a tcp user of an asynchronous error; 1643 * store error as soft error, but wake up user 1644 * (for now, won't do anything until can select for soft error). 1645 * 1646 * Do not wake up user since there currently is no mechanism for 1647 * reporting soft errors (yet - a kqueue filter may be added). 1648 */ 1649 static struct inpcb * 1650 tcp_notify(struct inpcb *inp, int error) 1651 { 1652 struct tcpcb *tp; 1653 1654 INP_INFO_LOCK_ASSERT(&V_tcbinfo); 1655 INP_WLOCK_ASSERT(inp); 1656 1657 if ((inp->inp_flags & INP_TIMEWAIT) || 1658 (inp->inp_flags & INP_DROPPED)) 1659 return (inp); 1660 1661 tp = intotcpcb(inp); 1662 KASSERT(tp != NULL, ("tcp_notify: tp == NULL")); 1663 1664 /* 1665 * Ignore some errors if we are hooked up. 1666 * If connection hasn't completed, has retransmitted several times, 1667 * and receives a second error, give up now. This is better 1668 * than waiting a long time to establish a connection that 1669 * can never complete. 1670 */ 1671 if (tp->t_state == TCPS_ESTABLISHED && 1672 (error == EHOSTUNREACH || error == ENETUNREACH || 1673 error == EHOSTDOWN)) { 1674 if (inp->inp_route.ro_rt) { 1675 RTFREE(inp->inp_route.ro_rt); 1676 inp->inp_route.ro_rt = (struct rtentry *)NULL; 1677 } 1678 return (inp); 1679 } else if (tp->t_state < TCPS_ESTABLISHED && tp->t_rxtshift > 3 && 1680 tp->t_softerror) { 1681 tp = tcp_drop(tp, error); 1682 if (tp != NULL) 1683 return (inp); 1684 else 1685 return (NULL); 1686 } else { 1687 tp->t_softerror = error; 1688 return (inp); 1689 } 1690 #if 0 1691 wakeup( &so->so_timeo); 1692 sorwakeup(so); 1693 sowwakeup(so); 1694 #endif 1695 } 1696 1697 static int 1698 tcp_pcblist(SYSCTL_HANDLER_ARGS) 1699 { 1700 int error, i, m, n, pcb_count; 1701 struct inpcb *inp, **inp_list; 1702 inp_gen_t gencnt; 1703 struct xinpgen xig; 1704 1705 /* 1706 * The process of preparing the TCB list is too time-consuming and 1707 * resource-intensive to repeat twice on every request. 1708 */ 1709 if (req->oldptr == NULL) { 1710 n = V_tcbinfo.ipi_count + 1711 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); 1712 n += imax(n / 8, 10); 1713 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xtcpcb); 1714 return (0); 1715 } 1716 1717 if (req->newptr != NULL) 1718 return (EPERM); 1719 1720 /* 1721 * OK, now we're committed to doing something. 1722 */ 1723 INP_LIST_RLOCK(&V_tcbinfo); 1724 gencnt = V_tcbinfo.ipi_gencnt; 1725 n = V_tcbinfo.ipi_count; 1726 INP_LIST_RUNLOCK(&V_tcbinfo); 1727 1728 m = counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); 1729 1730 error = sysctl_wire_old_buffer(req, 2 * (sizeof xig) 1731 + (n + m) * sizeof(struct xtcpcb)); 1732 if (error != 0) 1733 return (error); 1734 1735 xig.xig_len = sizeof xig; 1736 xig.xig_count = n + m; 1737 xig.xig_gen = gencnt; 1738 xig.xig_sogen = so_gencnt; 1739 error = SYSCTL_OUT(req, &xig, sizeof xig); 1740 if (error) 1741 return (error); 1742 1743 error = syncache_pcblist(req, m, &pcb_count); 1744 if (error) 1745 return (error); 1746 1747 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK); 1748 1749 INP_INFO_WLOCK(&V_tcbinfo); 1750 for (inp = LIST_FIRST(V_tcbinfo.ipi_listhead), i = 0; 1751 inp != NULL && i < n; inp = LIST_NEXT(inp, inp_list)) { 1752 INP_WLOCK(inp); 1753 if (inp->inp_gencnt <= gencnt) { 1754 /* 1755 * XXX: This use of cr_cansee(), introduced with 1756 * TCP state changes, is not quite right, but for 1757 * now, better than nothing. 1758 */ 1759 if (inp->inp_flags & INP_TIMEWAIT) { 1760 if (intotw(inp) != NULL) 1761 error = cr_cansee(req->td->td_ucred, 1762 intotw(inp)->tw_cred); 1763 else 1764 error = EINVAL; /* Skip this inp. */ 1765 } else 1766 error = cr_canseeinpcb(req->td->td_ucred, inp); 1767 if (error == 0) { 1768 in_pcbref(inp); 1769 inp_list[i++] = inp; 1770 } 1771 } 1772 INP_WUNLOCK(inp); 1773 } 1774 INP_INFO_WUNLOCK(&V_tcbinfo); 1775 n = i; 1776 1777 error = 0; 1778 for (i = 0; i < n; i++) { 1779 inp = inp_list[i]; 1780 INP_RLOCK(inp); 1781 if (inp->inp_gencnt <= gencnt) { 1782 struct xtcpcb xt; 1783 void *inp_ppcb; 1784 1785 bzero(&xt, sizeof(xt)); 1786 xt.xt_len = sizeof xt; 1787 /* XXX should avoid extra copy */ 1788 bcopy(inp, &xt.xt_inp, sizeof *inp); 1789 inp_ppcb = inp->inp_ppcb; 1790 if (inp_ppcb == NULL) 1791 bzero((char *) &xt.xt_tp, sizeof xt.xt_tp); 1792 else if (inp->inp_flags & INP_TIMEWAIT) { 1793 bzero((char *) &xt.xt_tp, sizeof xt.xt_tp); 1794 xt.xt_tp.t_state = TCPS_TIME_WAIT; 1795 } else { 1796 bcopy(inp_ppcb, &xt.xt_tp, sizeof xt.xt_tp); 1797 if (xt.xt_tp.t_timers) 1798 tcp_timer_to_xtimer(&xt.xt_tp, xt.xt_tp.t_timers, &xt.xt_timer); 1799 } 1800 if (inp->inp_socket != NULL) 1801 sotoxsocket(inp->inp_socket, &xt.xt_socket); 1802 else { 1803 bzero(&xt.xt_socket, sizeof xt.xt_socket); 1804 xt.xt_socket.xso_protocol = IPPROTO_TCP; 1805 } 1806 xt.xt_inp.inp_gencnt = inp->inp_gencnt; 1807 INP_RUNLOCK(inp); 1808 error = SYSCTL_OUT(req, &xt, sizeof xt); 1809 } else 1810 INP_RUNLOCK(inp); 1811 } 1812 INP_INFO_RLOCK(&V_tcbinfo); 1813 for (i = 0; i < n; i++) { 1814 inp = inp_list[i]; 1815 INP_RLOCK(inp); 1816 if (!in_pcbrele_rlocked(inp)) 1817 INP_RUNLOCK(inp); 1818 } 1819 INP_INFO_RUNLOCK(&V_tcbinfo); 1820 1821 if (!error) { 1822 /* 1823 * Give the user an updated idea of our state. 1824 * If the generation differs from what we told 1825 * her before, she knows that something happened 1826 * while we were processing this request, and it 1827 * might be necessary to retry. 1828 */ 1829 INP_LIST_RLOCK(&V_tcbinfo); 1830 xig.xig_gen = V_tcbinfo.ipi_gencnt; 1831 xig.xig_sogen = so_gencnt; 1832 xig.xig_count = V_tcbinfo.ipi_count + pcb_count; 1833 INP_LIST_RUNLOCK(&V_tcbinfo); 1834 error = SYSCTL_OUT(req, &xig, sizeof xig); 1835 } 1836 free(inp_list, M_TEMP); 1837 return (error); 1838 } 1839 1840 SYSCTL_PROC(_net_inet_tcp, TCPCTL_PCBLIST, pcblist, 1841 CTLTYPE_OPAQUE | CTLFLAG_RD, NULL, 0, 1842 tcp_pcblist, "S,xtcpcb", "List of active TCP connections"); 1843 1844 #ifdef INET 1845 static int 1846 tcp_getcred(SYSCTL_HANDLER_ARGS) 1847 { 1848 struct xucred xuc; 1849 struct sockaddr_in addrs[2]; 1850 struct inpcb *inp; 1851 int error; 1852 1853 error = priv_check(req->td, PRIV_NETINET_GETCRED); 1854 if (error) 1855 return (error); 1856 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 1857 if (error) 1858 return (error); 1859 inp = in_pcblookup(&V_tcbinfo, addrs[1].sin_addr, addrs[1].sin_port, 1860 addrs[0].sin_addr, addrs[0].sin_port, INPLOOKUP_RLOCKPCB, NULL); 1861 if (inp != NULL) { 1862 if (inp->inp_socket == NULL) 1863 error = ENOENT; 1864 if (error == 0) 1865 error = cr_canseeinpcb(req->td->td_ucred, inp); 1866 if (error == 0) 1867 cru2x(inp->inp_cred, &xuc); 1868 INP_RUNLOCK(inp); 1869 } else 1870 error = ENOENT; 1871 if (error == 0) 1872 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 1873 return (error); 1874 } 1875 1876 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, getcred, 1877 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0, 1878 tcp_getcred, "S,xucred", "Get the xucred of a TCP connection"); 1879 #endif /* INET */ 1880 1881 #ifdef INET6 1882 static int 1883 tcp6_getcred(SYSCTL_HANDLER_ARGS) 1884 { 1885 struct xucred xuc; 1886 struct sockaddr_in6 addrs[2]; 1887 struct inpcb *inp; 1888 int error; 1889 #ifdef INET 1890 int mapped = 0; 1891 #endif 1892 1893 error = priv_check(req->td, PRIV_NETINET_GETCRED); 1894 if (error) 1895 return (error); 1896 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 1897 if (error) 1898 return (error); 1899 if ((error = sa6_embedscope(&addrs[0], V_ip6_use_defzone)) != 0 || 1900 (error = sa6_embedscope(&addrs[1], V_ip6_use_defzone)) != 0) { 1901 return (error); 1902 } 1903 if (IN6_IS_ADDR_V4MAPPED(&addrs[0].sin6_addr)) { 1904 #ifdef INET 1905 if (IN6_IS_ADDR_V4MAPPED(&addrs[1].sin6_addr)) 1906 mapped = 1; 1907 else 1908 #endif 1909 return (EINVAL); 1910 } 1911 1912 #ifdef INET 1913 if (mapped == 1) 1914 inp = in_pcblookup(&V_tcbinfo, 1915 *(struct in_addr *)&addrs[1].sin6_addr.s6_addr[12], 1916 addrs[1].sin6_port, 1917 *(struct in_addr *)&addrs[0].sin6_addr.s6_addr[12], 1918 addrs[0].sin6_port, INPLOOKUP_RLOCKPCB, NULL); 1919 else 1920 #endif 1921 inp = in6_pcblookup(&V_tcbinfo, 1922 &addrs[1].sin6_addr, addrs[1].sin6_port, 1923 &addrs[0].sin6_addr, addrs[0].sin6_port, 1924 INPLOOKUP_RLOCKPCB, NULL); 1925 if (inp != NULL) { 1926 if (inp->inp_socket == NULL) 1927 error = ENOENT; 1928 if (error == 0) 1929 error = cr_canseeinpcb(req->td->td_ucred, inp); 1930 if (error == 0) 1931 cru2x(inp->inp_cred, &xuc); 1932 INP_RUNLOCK(inp); 1933 } else 1934 error = ENOENT; 1935 if (error == 0) 1936 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 1937 return (error); 1938 } 1939 1940 SYSCTL_PROC(_net_inet6_tcp6, OID_AUTO, getcred, 1941 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0, 1942 tcp6_getcred, "S,xucred", "Get the xucred of a TCP6 connection"); 1943 #endif /* INET6 */ 1944 1945 1946 #ifdef INET 1947 void 1948 tcp_ctlinput(int cmd, struct sockaddr *sa, void *vip) 1949 { 1950 struct ip *ip = vip; 1951 struct tcphdr *th; 1952 struct in_addr faddr; 1953 struct inpcb *inp; 1954 struct tcpcb *tp; 1955 struct inpcb *(*notify)(struct inpcb *, int) = tcp_notify; 1956 struct icmp *icp; 1957 struct in_conninfo inc; 1958 tcp_seq icmp_tcp_seq; 1959 int mtu; 1960 1961 faddr = ((struct sockaddr_in *)sa)->sin_addr; 1962 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY) 1963 return; 1964 1965 if (cmd == PRC_MSGSIZE) 1966 notify = tcp_mtudisc_notify; 1967 else if (V_icmp_may_rst && (cmd == PRC_UNREACH_ADMIN_PROHIB || 1968 cmd == PRC_UNREACH_PORT || cmd == PRC_TIMXCEED_INTRANS) && ip) 1969 notify = tcp_drop_syn_sent; 1970 1971 /* 1972 * Hostdead is ugly because it goes linearly through all PCBs. 1973 * XXX: We never get this from ICMP, otherwise it makes an 1974 * excellent DoS attack on machines with many connections. 1975 */ 1976 else if (cmd == PRC_HOSTDEAD) 1977 ip = NULL; 1978 else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0) 1979 return; 1980 1981 if (ip == NULL) { 1982 in_pcbnotifyall(&V_tcbinfo, faddr, inetctlerrmap[cmd], notify); 1983 return; 1984 } 1985 1986 icp = (struct icmp *)((caddr_t)ip - offsetof(struct icmp, icmp_ip)); 1987 th = (struct tcphdr *)((caddr_t)ip + (ip->ip_hl << 2)); 1988 INP_INFO_RLOCK(&V_tcbinfo); 1989 inp = in_pcblookup(&V_tcbinfo, faddr, th->th_dport, ip->ip_src, 1990 th->th_sport, INPLOOKUP_WLOCKPCB, NULL); 1991 if (inp != NULL && PRC_IS_REDIRECT(cmd)) { 1992 /* signal EHOSTDOWN, as it flushes the cached route */ 1993 inp = (*notify)(inp, EHOSTDOWN); 1994 if (inp != NULL) 1995 INP_WUNLOCK(inp); 1996 } else if (inp != NULL) { 1997 if (!(inp->inp_flags & INP_TIMEWAIT) && 1998 !(inp->inp_flags & INP_DROPPED) && 1999 !(inp->inp_socket == NULL)) { 2000 icmp_tcp_seq = ntohl(th->th_seq); 2001 tp = intotcpcb(inp); 2002 if (SEQ_GEQ(icmp_tcp_seq, tp->snd_una) && 2003 SEQ_LT(icmp_tcp_seq, tp->snd_max)) { 2004 if (cmd == PRC_MSGSIZE) { 2005 /* 2006 * MTU discovery: 2007 * If we got a needfrag set the MTU 2008 * in the route to the suggested new 2009 * value (if given) and then notify. 2010 */ 2011 mtu = ntohs(icp->icmp_nextmtu); 2012 /* 2013 * If no alternative MTU was 2014 * proposed, try the next smaller 2015 * one. 2016 */ 2017 if (!mtu) 2018 mtu = ip_next_mtu( 2019 ntohs(ip->ip_len), 1); 2020 if (mtu < V_tcp_minmss + 2021 sizeof(struct tcpiphdr)) 2022 mtu = V_tcp_minmss + 2023 sizeof(struct tcpiphdr); 2024 /* 2025 * Only process the offered MTU if it 2026 * is smaller than the current one. 2027 */ 2028 if (mtu < tp->t_maxseg + 2029 sizeof(struct tcpiphdr)) { 2030 bzero(&inc, sizeof(inc)); 2031 inc.inc_faddr = faddr; 2032 inc.inc_fibnum = 2033 inp->inp_inc.inc_fibnum; 2034 tcp_hc_updatemtu(&inc, mtu); 2035 tcp_mtudisc(inp, mtu); 2036 } 2037 } else 2038 inp = (*notify)(inp, 2039 inetctlerrmap[cmd]); 2040 } 2041 } 2042 if (inp != NULL) 2043 INP_WUNLOCK(inp); 2044 } else { 2045 bzero(&inc, sizeof(inc)); 2046 inc.inc_fport = th->th_dport; 2047 inc.inc_lport = th->th_sport; 2048 inc.inc_faddr = faddr; 2049 inc.inc_laddr = ip->ip_src; 2050 syncache_unreach(&inc, th); 2051 } 2052 INP_INFO_RUNLOCK(&V_tcbinfo); 2053 } 2054 #endif /* INET */ 2055 2056 #ifdef INET6 2057 void 2058 tcp6_ctlinput(int cmd, struct sockaddr *sa, void *d) 2059 { 2060 struct in6_addr *dst; 2061 struct tcphdr *th; 2062 struct inpcb *(*notify)(struct inpcb *, int) = tcp_notify; 2063 struct ip6_hdr *ip6; 2064 struct mbuf *m; 2065 struct inpcb *inp; 2066 struct tcpcb *tp; 2067 struct icmp6_hdr *icmp6; 2068 struct ip6ctlparam *ip6cp = NULL; 2069 const struct sockaddr_in6 *sa6_src = NULL; 2070 struct in_conninfo inc; 2071 tcp_seq icmp_tcp_seq; 2072 unsigned int mtu; 2073 unsigned int off; 2074 2075 2076 if (sa->sa_family != AF_INET6 || 2077 sa->sa_len != sizeof(struct sockaddr_in6)) 2078 return; 2079 2080 /* if the parameter is from icmp6, decode it. */ 2081 if (d != NULL) { 2082 ip6cp = (struct ip6ctlparam *)d; 2083 icmp6 = ip6cp->ip6c_icmp6; 2084 m = ip6cp->ip6c_m; 2085 ip6 = ip6cp->ip6c_ip6; 2086 off = ip6cp->ip6c_off; 2087 sa6_src = ip6cp->ip6c_src; 2088 dst = ip6cp->ip6c_finaldst; 2089 } else { 2090 m = NULL; 2091 ip6 = NULL; 2092 off = 0; /* fool gcc */ 2093 sa6_src = &sa6_any; 2094 dst = NULL; 2095 } 2096 2097 if (cmd == PRC_MSGSIZE) 2098 notify = tcp_mtudisc_notify; 2099 else if (V_icmp_may_rst && (cmd == PRC_UNREACH_ADMIN_PROHIB || 2100 cmd == PRC_UNREACH_PORT || cmd == PRC_TIMXCEED_INTRANS) && 2101 ip6 != NULL) 2102 notify = tcp_drop_syn_sent; 2103 2104 /* 2105 * Hostdead is ugly because it goes linearly through all PCBs. 2106 * XXX: We never get this from ICMP, otherwise it makes an 2107 * excellent DoS attack on machines with many connections. 2108 */ 2109 else if (cmd == PRC_HOSTDEAD) 2110 ip6 = NULL; 2111 else if ((unsigned)cmd >= PRC_NCMDS || inet6ctlerrmap[cmd] == 0) 2112 return; 2113 2114 if (ip6 == NULL) { 2115 in6_pcbnotify(&V_tcbinfo, sa, 0, 2116 (const struct sockaddr *)sa6_src, 2117 0, cmd, NULL, notify); 2118 return; 2119 } 2120 2121 /* Check if we can safely get the ports from the tcp hdr */ 2122 if (m == NULL || 2123 (m->m_pkthdr.len < 2124 (int32_t) (off + offsetof(struct tcphdr, th_seq)))) { 2125 return; 2126 } 2127 2128 th = (struct tcphdr *) mtodo(ip6cp->ip6c_m, ip6cp->ip6c_off); 2129 INP_INFO_RLOCK(&V_tcbinfo); 2130 inp = in6_pcblookup(&V_tcbinfo, &ip6->ip6_dst, th->th_dport, 2131 &ip6->ip6_src, th->th_sport, INPLOOKUP_WLOCKPCB, NULL); 2132 if (inp != NULL && PRC_IS_REDIRECT(cmd)) { 2133 /* signal EHOSTDOWN, as it flushes the cached route */ 2134 inp = (*notify)(inp, EHOSTDOWN); 2135 if (inp != NULL) 2136 INP_WUNLOCK(inp); 2137 } else if (inp != NULL) { 2138 if (!(inp->inp_flags & INP_TIMEWAIT) && 2139 !(inp->inp_flags & INP_DROPPED) && 2140 !(inp->inp_socket == NULL)) { 2141 icmp_tcp_seq = ntohl(th->th_seq); 2142 tp = intotcpcb(inp); 2143 if (SEQ_GEQ(icmp_tcp_seq, tp->snd_una) && 2144 SEQ_LT(icmp_tcp_seq, tp->snd_max)) { 2145 if (cmd == PRC_MSGSIZE) { 2146 /* 2147 * MTU discovery: 2148 * If we got a needfrag set the MTU 2149 * in the route to the suggested new 2150 * value (if given) and then notify. 2151 */ 2152 mtu = ntohl(icmp6->icmp6_mtu); 2153 /* 2154 * If no alternative MTU was 2155 * proposed, or the proposed 2156 * MTU was too small, set to 2157 * the min. 2158 */ 2159 if (mtu < IPV6_MMTU) 2160 mtu = IPV6_MMTU - 8; 2161 2162 2163 bzero(&inc, sizeof(inc)); 2164 inc.inc_fibnum = M_GETFIB(m); 2165 inc.inc_flags |= INC_ISIPV6; 2166 inc.inc6_faddr = *dst; 2167 if (in6_setscope(&inc.inc6_faddr, 2168 m->m_pkthdr.rcvif, NULL)) 2169 goto unlock_inp; 2170 2171 /* 2172 * Only process the offered MTU if it 2173 * is smaller than the current one. 2174 */ 2175 if (mtu < tp->t_maxseg + 2176 (sizeof (*th) + sizeof (*ip6))) { 2177 tcp_hc_updatemtu(&inc, mtu); 2178 tcp_mtudisc(inp, mtu); 2179 ICMP6STAT_INC(icp6s_pmtuchg); 2180 } 2181 } else 2182 inp = (*notify)(inp, 2183 inet6ctlerrmap[cmd]); 2184 } 2185 } 2186 unlock_inp: 2187 if (inp != NULL) 2188 INP_WUNLOCK(inp); 2189 } else { 2190 bzero(&inc, sizeof(inc)); 2191 inc.inc_fibnum = M_GETFIB(m); 2192 inc.inc_flags |= INC_ISIPV6; 2193 inc.inc_fport = th->th_dport; 2194 inc.inc_lport = th->th_sport; 2195 inc.inc6_faddr = *dst; 2196 inc.inc6_laddr = ip6->ip6_src; 2197 syncache_unreach(&inc, th); 2198 } 2199 INP_INFO_RUNLOCK(&V_tcbinfo); 2200 } 2201 #endif /* INET6 */ 2202 2203 2204 /* 2205 * Following is where TCP initial sequence number generation occurs. 2206 * 2207 * There are two places where we must use initial sequence numbers: 2208 * 1. In SYN-ACK packets. 2209 * 2. In SYN packets. 2210 * 2211 * All ISNs for SYN-ACK packets are generated by the syncache. See 2212 * tcp_syncache.c for details. 2213 * 2214 * The ISNs in SYN packets must be monotonic; TIME_WAIT recycling 2215 * depends on this property. In addition, these ISNs should be 2216 * unguessable so as to prevent connection hijacking. To satisfy 2217 * the requirements of this situation, the algorithm outlined in 2218 * RFC 1948 is used, with only small modifications. 2219 * 2220 * Implementation details: 2221 * 2222 * Time is based off the system timer, and is corrected so that it 2223 * increases by one megabyte per second. This allows for proper 2224 * recycling on high speed LANs while still leaving over an hour 2225 * before rollover. 2226 * 2227 * As reading the *exact* system time is too expensive to be done 2228 * whenever setting up a TCP connection, we increment the time 2229 * offset in two ways. First, a small random positive increment 2230 * is added to isn_offset for each connection that is set up. 2231 * Second, the function tcp_isn_tick fires once per clock tick 2232 * and increments isn_offset as necessary so that sequence numbers 2233 * are incremented at approximately ISN_BYTES_PER_SECOND. The 2234 * random positive increments serve only to ensure that the same 2235 * exact sequence number is never sent out twice (as could otherwise 2236 * happen when a port is recycled in less than the system tick 2237 * interval.) 2238 * 2239 * net.inet.tcp.isn_reseed_interval controls the number of seconds 2240 * between seeding of isn_secret. This is normally set to zero, 2241 * as reseeding should not be necessary. 2242 * 2243 * Locking of the global variables isn_secret, isn_last_reseed, isn_offset, 2244 * isn_offset_old, and isn_ctx is performed using the TCP pcbinfo lock. In 2245 * general, this means holding an exclusive (write) lock. 2246 */ 2247 2248 #define ISN_BYTES_PER_SECOND 1048576 2249 #define ISN_STATIC_INCREMENT 4096 2250 #define ISN_RANDOM_INCREMENT (4096 - 1) 2251 2252 static VNET_DEFINE(u_char, isn_secret[32]); 2253 static VNET_DEFINE(int, isn_last); 2254 static VNET_DEFINE(int, isn_last_reseed); 2255 static VNET_DEFINE(u_int32_t, isn_offset); 2256 static VNET_DEFINE(u_int32_t, isn_offset_old); 2257 2258 #define V_isn_secret VNET(isn_secret) 2259 #define V_isn_last VNET(isn_last) 2260 #define V_isn_last_reseed VNET(isn_last_reseed) 2261 #define V_isn_offset VNET(isn_offset) 2262 #define V_isn_offset_old VNET(isn_offset_old) 2263 2264 tcp_seq 2265 tcp_new_isn(struct tcpcb *tp) 2266 { 2267 MD5_CTX isn_ctx; 2268 u_int32_t md5_buffer[4]; 2269 tcp_seq new_isn; 2270 u_int32_t projected_offset; 2271 2272 INP_WLOCK_ASSERT(tp->t_inpcb); 2273 2274 ISN_LOCK(); 2275 /* Seed if this is the first use, reseed if requested. */ 2276 if ((V_isn_last_reseed == 0) || ((V_tcp_isn_reseed_interval > 0) && 2277 (((u_int)V_isn_last_reseed + (u_int)V_tcp_isn_reseed_interval*hz) 2278 < (u_int)ticks))) { 2279 read_random(&V_isn_secret, sizeof(V_isn_secret)); 2280 V_isn_last_reseed = ticks; 2281 } 2282 2283 /* Compute the md5 hash and return the ISN. */ 2284 MD5Init(&isn_ctx); 2285 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_fport, sizeof(u_short)); 2286 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_lport, sizeof(u_short)); 2287 #ifdef INET6 2288 if ((tp->t_inpcb->inp_vflag & INP_IPV6) != 0) { 2289 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->in6p_faddr, 2290 sizeof(struct in6_addr)); 2291 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->in6p_laddr, 2292 sizeof(struct in6_addr)); 2293 } else 2294 #endif 2295 { 2296 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_faddr, 2297 sizeof(struct in_addr)); 2298 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_laddr, 2299 sizeof(struct in_addr)); 2300 } 2301 MD5Update(&isn_ctx, (u_char *) &V_isn_secret, sizeof(V_isn_secret)); 2302 MD5Final((u_char *) &md5_buffer, &isn_ctx); 2303 new_isn = (tcp_seq) md5_buffer[0]; 2304 V_isn_offset += ISN_STATIC_INCREMENT + 2305 (arc4random() & ISN_RANDOM_INCREMENT); 2306 if (ticks != V_isn_last) { 2307 projected_offset = V_isn_offset_old + 2308 ISN_BYTES_PER_SECOND / hz * (ticks - V_isn_last); 2309 if (SEQ_GT(projected_offset, V_isn_offset)) 2310 V_isn_offset = projected_offset; 2311 V_isn_offset_old = V_isn_offset; 2312 V_isn_last = ticks; 2313 } 2314 new_isn += V_isn_offset; 2315 ISN_UNLOCK(); 2316 return (new_isn); 2317 } 2318 2319 /* 2320 * When a specific ICMP unreachable message is received and the 2321 * connection state is SYN-SENT, drop the connection. This behavior 2322 * is controlled by the icmp_may_rst sysctl. 2323 */ 2324 struct inpcb * 2325 tcp_drop_syn_sent(struct inpcb *inp, int errno) 2326 { 2327 struct tcpcb *tp; 2328 2329 INP_INFO_RLOCK_ASSERT(&V_tcbinfo); 2330 INP_WLOCK_ASSERT(inp); 2331 2332 if ((inp->inp_flags & INP_TIMEWAIT) || 2333 (inp->inp_flags & INP_DROPPED)) 2334 return (inp); 2335 2336 tp = intotcpcb(inp); 2337 if (tp->t_state != TCPS_SYN_SENT) 2338 return (inp); 2339 2340 tp = tcp_drop(tp, errno); 2341 if (tp != NULL) 2342 return (inp); 2343 else 2344 return (NULL); 2345 } 2346 2347 /* 2348 * When `need fragmentation' ICMP is received, update our idea of the MSS 2349 * based on the new value. Also nudge TCP to send something, since we 2350 * know the packet we just sent was dropped. 2351 * This duplicates some code in the tcp_mss() function in tcp_input.c. 2352 */ 2353 static struct inpcb * 2354 tcp_mtudisc_notify(struct inpcb *inp, int error) 2355 { 2356 2357 tcp_mtudisc(inp, -1); 2358 return (inp); 2359 } 2360 2361 static void 2362 tcp_mtudisc(struct inpcb *inp, int mtuoffer) 2363 { 2364 struct tcpcb *tp; 2365 struct socket *so; 2366 2367 INP_WLOCK_ASSERT(inp); 2368 if ((inp->inp_flags & INP_TIMEWAIT) || 2369 (inp->inp_flags & INP_DROPPED)) 2370 return; 2371 2372 tp = intotcpcb(inp); 2373 KASSERT(tp != NULL, ("tcp_mtudisc: tp == NULL")); 2374 2375 tcp_mss_update(tp, -1, mtuoffer, NULL, NULL); 2376 2377 so = inp->inp_socket; 2378 SOCKBUF_LOCK(&so->so_snd); 2379 /* If the mss is larger than the socket buffer, decrease the mss. */ 2380 if (so->so_snd.sb_hiwat < tp->t_maxseg) 2381 tp->t_maxseg = so->so_snd.sb_hiwat; 2382 SOCKBUF_UNLOCK(&so->so_snd); 2383 2384 TCPSTAT_INC(tcps_mturesent); 2385 tp->t_rtttime = 0; 2386 tp->snd_nxt = tp->snd_una; 2387 tcp_free_sackholes(tp); 2388 tp->snd_recover = tp->snd_max; 2389 if (tp->t_flags & TF_SACK_PERMIT) 2390 EXIT_FASTRECOVERY(tp->t_flags); 2391 tp->t_fb->tfb_tcp_output(tp); 2392 } 2393 2394 #ifdef INET 2395 /* 2396 * Look-up the routing entry to the peer of this inpcb. If no route 2397 * is found and it cannot be allocated, then return 0. This routine 2398 * is called by TCP routines that access the rmx structure and by 2399 * tcp_mss_update to get the peer/interface MTU. 2400 */ 2401 uint32_t 2402 tcp_maxmtu(struct in_conninfo *inc, struct tcp_ifcap *cap) 2403 { 2404 struct nhop4_extended nh4; 2405 struct ifnet *ifp; 2406 uint32_t maxmtu = 0; 2407 2408 KASSERT(inc != NULL, ("tcp_maxmtu with NULL in_conninfo pointer")); 2409 2410 if (inc->inc_faddr.s_addr != INADDR_ANY) { 2411 2412 if (fib4_lookup_nh_ext(inc->inc_fibnum, inc->inc_faddr, 2413 NHR_REF, 0, &nh4) != 0) 2414 return (0); 2415 2416 ifp = nh4.nh_ifp; 2417 maxmtu = nh4.nh_mtu; 2418 2419 /* Report additional interface capabilities. */ 2420 if (cap != NULL) { 2421 if (ifp->if_capenable & IFCAP_TSO4 && 2422 ifp->if_hwassist & CSUM_TSO) { 2423 cap->ifcap |= CSUM_TSO; 2424 cap->tsomax = ifp->if_hw_tsomax; 2425 cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount; 2426 cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize; 2427 } 2428 } 2429 fib4_free_nh_ext(inc->inc_fibnum, &nh4); 2430 } 2431 return (maxmtu); 2432 } 2433 #endif /* INET */ 2434 2435 #ifdef INET6 2436 uint32_t 2437 tcp_maxmtu6(struct in_conninfo *inc, struct tcp_ifcap *cap) 2438 { 2439 struct nhop6_extended nh6; 2440 struct in6_addr dst6; 2441 uint32_t scopeid; 2442 struct ifnet *ifp; 2443 uint32_t maxmtu = 0; 2444 2445 KASSERT(inc != NULL, ("tcp_maxmtu6 with NULL in_conninfo pointer")); 2446 2447 if (!IN6_IS_ADDR_UNSPECIFIED(&inc->inc6_faddr)) { 2448 in6_splitscope(&inc->inc6_faddr, &dst6, &scopeid); 2449 if (fib6_lookup_nh_ext(inc->inc_fibnum, &dst6, scopeid, 0, 2450 0, &nh6) != 0) 2451 return (0); 2452 2453 ifp = nh6.nh_ifp; 2454 maxmtu = nh6.nh_mtu; 2455 2456 /* Report additional interface capabilities. */ 2457 if (cap != NULL) { 2458 if (ifp->if_capenable & IFCAP_TSO6 && 2459 ifp->if_hwassist & CSUM_TSO) { 2460 cap->ifcap |= CSUM_TSO; 2461 cap->tsomax = ifp->if_hw_tsomax; 2462 cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount; 2463 cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize; 2464 } 2465 } 2466 fib6_free_nh_ext(inc->inc_fibnum, &nh6); 2467 } 2468 2469 return (maxmtu); 2470 } 2471 #endif /* INET6 */ 2472 2473 /* 2474 * Calculate effective SMSS per RFC5681 definition for a given TCP 2475 * connection at its current state, taking into account SACK and etc. 2476 */ 2477 u_int 2478 tcp_maxseg(const struct tcpcb *tp) 2479 { 2480 u_int optlen; 2481 2482 if (tp->t_flags & TF_NOOPT) 2483 return (tp->t_maxseg); 2484 2485 /* 2486 * Here we have a simplified code from tcp_addoptions(), 2487 * without a proper loop, and having most of paddings hardcoded. 2488 * We might make mistakes with padding here in some edge cases, 2489 * but this is harmless, since result of tcp_maxseg() is used 2490 * only in cwnd and ssthresh estimations. 2491 */ 2492 #define PAD(len) ((((len) / 4) + !!((len) % 4)) * 4) 2493 if (TCPS_HAVEESTABLISHED(tp->t_state)) { 2494 if (tp->t_flags & TF_RCVD_TSTMP) 2495 optlen = TCPOLEN_TSTAMP_APPA; 2496 else 2497 optlen = 0; 2498 #ifdef TCP_SIGNATURE 2499 if (tp->t_flags & TF_SIGNATURE) 2500 optlen += PAD(TCPOLEN_SIGNATURE); 2501 #endif 2502 if ((tp->t_flags & TF_SACK_PERMIT) && tp->rcv_numsacks > 0) { 2503 optlen += TCPOLEN_SACKHDR; 2504 optlen += tp->rcv_numsacks * TCPOLEN_SACK; 2505 optlen = PAD(optlen); 2506 } 2507 } else { 2508 if (tp->t_flags & TF_REQ_TSTMP) 2509 optlen = TCPOLEN_TSTAMP_APPA; 2510 else 2511 optlen = PAD(TCPOLEN_MAXSEG); 2512 if (tp->t_flags & TF_REQ_SCALE) 2513 optlen += PAD(TCPOLEN_WINDOW); 2514 #ifdef TCP_SIGNATURE 2515 if (tp->t_flags & TF_SIGNATURE) 2516 optlen += PAD(TCPOLEN_SIGNATURE); 2517 #endif 2518 if (tp->t_flags & TF_SACK_PERMIT) 2519 optlen += PAD(TCPOLEN_SACK_PERMITTED); 2520 } 2521 #undef PAD 2522 optlen = min(optlen, TCP_MAXOLEN); 2523 return (tp->t_maxseg - optlen); 2524 } 2525 2526 #ifdef IPSEC 2527 /* compute ESP/AH header size for TCP, including outer IP header. */ 2528 size_t 2529 ipsec_hdrsiz_tcp(struct tcpcb *tp) 2530 { 2531 struct inpcb *inp; 2532 struct mbuf *m; 2533 size_t hdrsiz; 2534 struct ip *ip; 2535 #ifdef INET6 2536 struct ip6_hdr *ip6; 2537 #endif 2538 struct tcphdr *th; 2539 2540 if ((tp == NULL) || ((inp = tp->t_inpcb) == NULL) || 2541 (!key_havesp(IPSEC_DIR_OUTBOUND))) 2542 return (0); 2543 m = m_gethdr(M_NOWAIT, MT_DATA); 2544 if (!m) 2545 return (0); 2546 2547 #ifdef INET6 2548 if ((inp->inp_vflag & INP_IPV6) != 0) { 2549 ip6 = mtod(m, struct ip6_hdr *); 2550 th = (struct tcphdr *)(ip6 + 1); 2551 m->m_pkthdr.len = m->m_len = 2552 sizeof(struct ip6_hdr) + sizeof(struct tcphdr); 2553 tcpip_fillheaders(inp, ip6, th); 2554 hdrsiz = ipsec_hdrsiz(m, IPSEC_DIR_OUTBOUND, inp); 2555 } else 2556 #endif /* INET6 */ 2557 { 2558 ip = mtod(m, struct ip *); 2559 th = (struct tcphdr *)(ip + 1); 2560 m->m_pkthdr.len = m->m_len = sizeof(struct tcpiphdr); 2561 tcpip_fillheaders(inp, ip, th); 2562 hdrsiz = ipsec_hdrsiz(m, IPSEC_DIR_OUTBOUND, inp); 2563 } 2564 2565 m_free(m); 2566 return (hdrsiz); 2567 } 2568 #endif /* IPSEC */ 2569 2570 #ifdef TCP_SIGNATURE 2571 /* 2572 * Callback function invoked by m_apply() to digest TCP segment data 2573 * contained within an mbuf chain. 2574 */ 2575 static int 2576 tcp_signature_apply(void *fstate, void *data, u_int len) 2577 { 2578 2579 MD5Update(fstate, (u_char *)data, len); 2580 return (0); 2581 } 2582 2583 /* 2584 * XXX The key is retrieved from the system's PF_KEY SADB, by keying a 2585 * search with the destination IP address, and a 'magic SPI' to be 2586 * determined by the application. This is hardcoded elsewhere to 1179 2587 */ 2588 struct secasvar * 2589 tcp_get_sav(struct mbuf *m, u_int direction) 2590 { 2591 union sockaddr_union dst; 2592 struct secasvar *sav; 2593 struct ip *ip; 2594 #ifdef INET6 2595 struct ip6_hdr *ip6; 2596 char ip6buf[INET6_ADDRSTRLEN]; 2597 #endif 2598 2599 /* Extract the destination from the IP header in the mbuf. */ 2600 bzero(&dst, sizeof(union sockaddr_union)); 2601 ip = mtod(m, struct ip *); 2602 #ifdef INET6 2603 ip6 = NULL; /* Make the compiler happy. */ 2604 #endif 2605 switch (ip->ip_v) { 2606 #ifdef INET 2607 case IPVERSION: 2608 dst.sa.sa_len = sizeof(struct sockaddr_in); 2609 dst.sa.sa_family = AF_INET; 2610 dst.sin.sin_addr = (direction == IPSEC_DIR_INBOUND) ? 2611 ip->ip_src : ip->ip_dst; 2612 break; 2613 #endif 2614 #ifdef INET6 2615 case (IPV6_VERSION >> 4): 2616 ip6 = mtod(m, struct ip6_hdr *); 2617 dst.sa.sa_len = sizeof(struct sockaddr_in6); 2618 dst.sa.sa_family = AF_INET6; 2619 dst.sin6.sin6_addr = (direction == IPSEC_DIR_INBOUND) ? 2620 ip6->ip6_src : ip6->ip6_dst; 2621 break; 2622 #endif 2623 default: 2624 return (NULL); 2625 /* NOTREACHED */ 2626 break; 2627 } 2628 2629 /* Look up an SADB entry which matches the address of the peer. */ 2630 sav = KEY_ALLOCSA(&dst, IPPROTO_TCP, htonl(TCP_SIG_SPI)); 2631 if (sav == NULL) { 2632 ipseclog((LOG_ERR, "%s: SADB lookup failed for %s\n", __func__, 2633 (ip->ip_v == IPVERSION) ? inet_ntoa(dst.sin.sin_addr) : 2634 #ifdef INET6 2635 (ip->ip_v == (IPV6_VERSION >> 4)) ? 2636 ip6_sprintf(ip6buf, &dst.sin6.sin6_addr) : 2637 #endif 2638 "(unsupported)")); 2639 } 2640 2641 return (sav); 2642 } 2643 2644 /* 2645 * Compute TCP-MD5 hash of a TCP segment. (RFC2385) 2646 * 2647 * Parameters: 2648 * m pointer to head of mbuf chain 2649 * len length of TCP segment data, excluding options 2650 * optlen length of TCP segment options 2651 * buf pointer to storage for computed MD5 digest 2652 * sav pointer to security assosiation 2653 * 2654 * We do this over ip, tcphdr, segment data, and the key in the SADB. 2655 * When called from tcp_input(), we can be sure that th_sum has been 2656 * zeroed out and verified already. 2657 * 2658 * Releases reference to SADB key before return. 2659 * 2660 * Return 0 if successful, otherwise return -1. 2661 * 2662 */ 2663 int 2664 tcp_signature_do_compute(struct mbuf *m, int len, int optlen, 2665 u_char *buf, struct secasvar *sav) 2666 { 2667 #ifdef INET 2668 struct ippseudo ippseudo; 2669 #endif 2670 MD5_CTX ctx; 2671 int doff; 2672 struct ip *ip; 2673 #ifdef INET 2674 struct ipovly *ipovly; 2675 #endif 2676 struct tcphdr *th; 2677 #ifdef INET6 2678 struct ip6_hdr *ip6; 2679 struct in6_addr in6; 2680 uint32_t plen; 2681 uint16_t nhdr; 2682 #endif 2683 u_short savecsum; 2684 2685 KASSERT(m != NULL, ("NULL mbuf chain")); 2686 KASSERT(buf != NULL, ("NULL signature pointer")); 2687 2688 /* Extract the destination from the IP header in the mbuf. */ 2689 ip = mtod(m, struct ip *); 2690 #ifdef INET6 2691 ip6 = NULL; /* Make the compiler happy. */ 2692 #endif 2693 2694 MD5Init(&ctx); 2695 /* 2696 * Step 1: Update MD5 hash with IP(v6) pseudo-header. 2697 * 2698 * XXX The ippseudo header MUST be digested in network byte order, 2699 * or else we'll fail the regression test. Assume all fields we've 2700 * been doing arithmetic on have been in host byte order. 2701 * XXX One cannot depend on ipovly->ih_len here. When called from 2702 * tcp_output(), the underlying ip_len member has not yet been set. 2703 */ 2704 switch (ip->ip_v) { 2705 #ifdef INET 2706 case IPVERSION: 2707 ipovly = (struct ipovly *)ip; 2708 ippseudo.ippseudo_src = ipovly->ih_src; 2709 ippseudo.ippseudo_dst = ipovly->ih_dst; 2710 ippseudo.ippseudo_pad = 0; 2711 ippseudo.ippseudo_p = IPPROTO_TCP; 2712 ippseudo.ippseudo_len = htons(len + sizeof(struct tcphdr) + 2713 optlen); 2714 MD5Update(&ctx, (char *)&ippseudo, sizeof(struct ippseudo)); 2715 2716 th = (struct tcphdr *)((u_char *)ip + sizeof(struct ip)); 2717 doff = sizeof(struct ip) + sizeof(struct tcphdr) + optlen; 2718 break; 2719 #endif 2720 #ifdef INET6 2721 /* 2722 * RFC 2385, 2.0 Proposal 2723 * For IPv6, the pseudo-header is as described in RFC 2460, namely the 2724 * 128-bit source IPv6 address, 128-bit destination IPv6 address, zero- 2725 * extended next header value (to form 32 bits), and 32-bit segment 2726 * length. 2727 * Note: Upper-Layer Packet Length comes before Next Header. 2728 */ 2729 case (IPV6_VERSION >> 4): 2730 in6 = ip6->ip6_src; 2731 in6_clearscope(&in6); 2732 MD5Update(&ctx, (char *)&in6, sizeof(struct in6_addr)); 2733 in6 = ip6->ip6_dst; 2734 in6_clearscope(&in6); 2735 MD5Update(&ctx, (char *)&in6, sizeof(struct in6_addr)); 2736 plen = htonl(len + sizeof(struct tcphdr) + optlen); 2737 MD5Update(&ctx, (char *)&plen, sizeof(uint32_t)); 2738 nhdr = 0; 2739 MD5Update(&ctx, (char *)&nhdr, sizeof(uint8_t)); 2740 MD5Update(&ctx, (char *)&nhdr, sizeof(uint8_t)); 2741 MD5Update(&ctx, (char *)&nhdr, sizeof(uint8_t)); 2742 nhdr = IPPROTO_TCP; 2743 MD5Update(&ctx, (char *)&nhdr, sizeof(uint8_t)); 2744 2745 th = (struct tcphdr *)((u_char *)ip6 + sizeof(struct ip6_hdr)); 2746 doff = sizeof(struct ip6_hdr) + sizeof(struct tcphdr) + optlen; 2747 break; 2748 #endif 2749 default: 2750 KEY_FREESAV(&sav); 2751 return (-1); 2752 /* NOTREACHED */ 2753 break; 2754 } 2755 2756 2757 /* 2758 * Step 2: Update MD5 hash with TCP header, excluding options. 2759 * The TCP checksum must be set to zero. 2760 */ 2761 savecsum = th->th_sum; 2762 th->th_sum = 0; 2763 MD5Update(&ctx, (char *)th, sizeof(struct tcphdr)); 2764 th->th_sum = savecsum; 2765 2766 /* 2767 * Step 3: Update MD5 hash with TCP segment data. 2768 * Use m_apply() to avoid an early m_pullup(). 2769 */ 2770 if (len > 0) 2771 m_apply(m, doff, len, tcp_signature_apply, &ctx); 2772 2773 /* 2774 * Step 4: Update MD5 hash with shared secret. 2775 */ 2776 MD5Update(&ctx, sav->key_auth->key_data, _KEYLEN(sav->key_auth)); 2777 MD5Final(buf, &ctx); 2778 2779 key_sa_recordxfer(sav, m); 2780 KEY_FREESAV(&sav); 2781 return (0); 2782 } 2783 2784 /* 2785 * Compute TCP-MD5 hash of a TCP segment. (RFC2385) 2786 * 2787 * Return 0 if successful, otherwise return -1. 2788 */ 2789 int 2790 tcp_signature_compute(struct mbuf *m, int _unused, int len, int optlen, 2791 u_char *buf, u_int direction) 2792 { 2793 struct secasvar *sav; 2794 2795 if ((sav = tcp_get_sav(m, direction)) == NULL) 2796 return (-1); 2797 2798 return (tcp_signature_do_compute(m, len, optlen, buf, sav)); 2799 } 2800 2801 /* 2802 * Verify the TCP-MD5 hash of a TCP segment. (RFC2385) 2803 * 2804 * Parameters: 2805 * m pointer to head of mbuf chain 2806 * len length of TCP segment data, excluding options 2807 * optlen length of TCP segment options 2808 * buf pointer to storage for computed MD5 digest 2809 * direction direction of flow (IPSEC_DIR_INBOUND or OUTBOUND) 2810 * 2811 * Return 1 if successful, otherwise return 0. 2812 */ 2813 int 2814 tcp_signature_verify(struct mbuf *m, int off0, int tlen, int optlen, 2815 struct tcpopt *to, struct tcphdr *th, u_int tcpbflag) 2816 { 2817 char tmpdigest[TCP_SIGLEN]; 2818 2819 if (tcp_sig_checksigs == 0) 2820 return (1); 2821 if ((tcpbflag & TF_SIGNATURE) == 0) { 2822 if ((to->to_flags & TOF_SIGNATURE) != 0) { 2823 2824 /* 2825 * If this socket is not expecting signature but 2826 * the segment contains signature just fail. 2827 */ 2828 TCPSTAT_INC(tcps_sig_err_sigopt); 2829 TCPSTAT_INC(tcps_sig_rcvbadsig); 2830 return (0); 2831 } 2832 2833 /* Signature is not expected, and not present in segment. */ 2834 return (1); 2835 } 2836 2837 /* 2838 * If this socket is expecting signature but the segment does not 2839 * contain any just fail. 2840 */ 2841 if ((to->to_flags & TOF_SIGNATURE) == 0) { 2842 TCPSTAT_INC(tcps_sig_err_nosigopt); 2843 TCPSTAT_INC(tcps_sig_rcvbadsig); 2844 return (0); 2845 } 2846 if (tcp_signature_compute(m, off0, tlen, optlen, &tmpdigest[0], 2847 IPSEC_DIR_INBOUND) == -1) { 2848 TCPSTAT_INC(tcps_sig_err_buildsig); 2849 TCPSTAT_INC(tcps_sig_rcvbadsig); 2850 return (0); 2851 } 2852 2853 if (bcmp(to->to_signature, &tmpdigest[0], TCP_SIGLEN) != 0) { 2854 TCPSTAT_INC(tcps_sig_rcvbadsig); 2855 return (0); 2856 } 2857 TCPSTAT_INC(tcps_sig_rcvgoodsig); 2858 return (1); 2859 } 2860 #endif /* TCP_SIGNATURE */ 2861 2862 static int 2863 sysctl_drop(SYSCTL_HANDLER_ARGS) 2864 { 2865 /* addrs[0] is a foreign socket, addrs[1] is a local one. */ 2866 struct sockaddr_storage addrs[2]; 2867 struct inpcb *inp; 2868 struct tcpcb *tp; 2869 struct tcptw *tw; 2870 struct sockaddr_in *fin, *lin; 2871 #ifdef INET6 2872 struct sockaddr_in6 *fin6, *lin6; 2873 #endif 2874 int error; 2875 2876 inp = NULL; 2877 fin = lin = NULL; 2878 #ifdef INET6 2879 fin6 = lin6 = NULL; 2880 #endif 2881 error = 0; 2882 2883 if (req->oldptr != NULL || req->oldlen != 0) 2884 return (EINVAL); 2885 if (req->newptr == NULL) 2886 return (EPERM); 2887 if (req->newlen < sizeof(addrs)) 2888 return (ENOMEM); 2889 error = SYSCTL_IN(req, &addrs, sizeof(addrs)); 2890 if (error) 2891 return (error); 2892 2893 switch (addrs[0].ss_family) { 2894 #ifdef INET6 2895 case AF_INET6: 2896 fin6 = (struct sockaddr_in6 *)&addrs[0]; 2897 lin6 = (struct sockaddr_in6 *)&addrs[1]; 2898 if (fin6->sin6_len != sizeof(struct sockaddr_in6) || 2899 lin6->sin6_len != sizeof(struct sockaddr_in6)) 2900 return (EINVAL); 2901 if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr)) { 2902 if (!IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr)) 2903 return (EINVAL); 2904 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[0]); 2905 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[1]); 2906 fin = (struct sockaddr_in *)&addrs[0]; 2907 lin = (struct sockaddr_in *)&addrs[1]; 2908 break; 2909 } 2910 error = sa6_embedscope(fin6, V_ip6_use_defzone); 2911 if (error) 2912 return (error); 2913 error = sa6_embedscope(lin6, V_ip6_use_defzone); 2914 if (error) 2915 return (error); 2916 break; 2917 #endif 2918 #ifdef INET 2919 case AF_INET: 2920 fin = (struct sockaddr_in *)&addrs[0]; 2921 lin = (struct sockaddr_in *)&addrs[1]; 2922 if (fin->sin_len != sizeof(struct sockaddr_in) || 2923 lin->sin_len != sizeof(struct sockaddr_in)) 2924 return (EINVAL); 2925 break; 2926 #endif 2927 default: 2928 return (EINVAL); 2929 } 2930 INP_INFO_RLOCK(&V_tcbinfo); 2931 switch (addrs[0].ss_family) { 2932 #ifdef INET6 2933 case AF_INET6: 2934 inp = in6_pcblookup(&V_tcbinfo, &fin6->sin6_addr, 2935 fin6->sin6_port, &lin6->sin6_addr, lin6->sin6_port, 2936 INPLOOKUP_WLOCKPCB, NULL); 2937 break; 2938 #endif 2939 #ifdef INET 2940 case AF_INET: 2941 inp = in_pcblookup(&V_tcbinfo, fin->sin_addr, fin->sin_port, 2942 lin->sin_addr, lin->sin_port, INPLOOKUP_WLOCKPCB, NULL); 2943 break; 2944 #endif 2945 } 2946 if (inp != NULL) { 2947 if (inp->inp_flags & INP_TIMEWAIT) { 2948 /* 2949 * XXXRW: There currently exists a state where an 2950 * inpcb is present, but its timewait state has been 2951 * discarded. For now, don't allow dropping of this 2952 * type of inpcb. 2953 */ 2954 tw = intotw(inp); 2955 if (tw != NULL) 2956 tcp_twclose(tw, 0); 2957 else 2958 INP_WUNLOCK(inp); 2959 } else if (!(inp->inp_flags & INP_DROPPED) && 2960 !(inp->inp_socket->so_options & SO_ACCEPTCONN)) { 2961 tp = intotcpcb(inp); 2962 tp = tcp_drop(tp, ECONNABORTED); 2963 if (tp != NULL) 2964 INP_WUNLOCK(inp); 2965 } else 2966 INP_WUNLOCK(inp); 2967 } else 2968 error = ESRCH; 2969 INP_INFO_RUNLOCK(&V_tcbinfo); 2970 return (error); 2971 } 2972 2973 SYSCTL_PROC(_net_inet_tcp, TCPCTL_DROP, drop, 2974 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP, NULL, 2975 0, sysctl_drop, "", "Drop TCP connection"); 2976 2977 /* 2978 * Generate a standardized TCP log line for use throughout the 2979 * tcp subsystem. Memory allocation is done with M_NOWAIT to 2980 * allow use in the interrupt context. 2981 * 2982 * NB: The caller MUST free(s, M_TCPLOG) the returned string. 2983 * NB: The function may return NULL if memory allocation failed. 2984 * 2985 * Due to header inclusion and ordering limitations the struct ip 2986 * and ip6_hdr pointers have to be passed as void pointers. 2987 */ 2988 char * 2989 tcp_log_vain(struct in_conninfo *inc, struct tcphdr *th, void *ip4hdr, 2990 const void *ip6hdr) 2991 { 2992 2993 /* Is logging enabled? */ 2994 if (tcp_log_in_vain == 0) 2995 return (NULL); 2996 2997 return (tcp_log_addr(inc, th, ip4hdr, ip6hdr)); 2998 } 2999 3000 char * 3001 tcp_log_addrs(struct in_conninfo *inc, struct tcphdr *th, void *ip4hdr, 3002 const void *ip6hdr) 3003 { 3004 3005 /* Is logging enabled? */ 3006 if (tcp_log_debug == 0) 3007 return (NULL); 3008 3009 return (tcp_log_addr(inc, th, ip4hdr, ip6hdr)); 3010 } 3011 3012 static char * 3013 tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th, void *ip4hdr, 3014 const void *ip6hdr) 3015 { 3016 char *s, *sp; 3017 size_t size; 3018 struct ip *ip; 3019 #ifdef INET6 3020 const struct ip6_hdr *ip6; 3021 3022 ip6 = (const struct ip6_hdr *)ip6hdr; 3023 #endif /* INET6 */ 3024 ip = (struct ip *)ip4hdr; 3025 3026 /* 3027 * The log line looks like this: 3028 * "TCP: [1.2.3.4]:50332 to [1.2.3.4]:80 tcpflags 0x2<SYN>" 3029 */ 3030 size = sizeof("TCP: []:12345 to []:12345 tcpflags 0x2<>") + 3031 sizeof(PRINT_TH_FLAGS) + 1 + 3032 #ifdef INET6 3033 2 * INET6_ADDRSTRLEN; 3034 #else 3035 2 * INET_ADDRSTRLEN; 3036 #endif /* INET6 */ 3037 3038 s = malloc(size, M_TCPLOG, M_ZERO|M_NOWAIT); 3039 if (s == NULL) 3040 return (NULL); 3041 3042 strcat(s, "TCP: ["); 3043 sp = s + strlen(s); 3044 3045 if (inc && ((inc->inc_flags & INC_ISIPV6) == 0)) { 3046 inet_ntoa_r(inc->inc_faddr, sp); 3047 sp = s + strlen(s); 3048 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport)); 3049 sp = s + strlen(s); 3050 inet_ntoa_r(inc->inc_laddr, sp); 3051 sp = s + strlen(s); 3052 sprintf(sp, "]:%i", ntohs(inc->inc_lport)); 3053 #ifdef INET6 3054 } else if (inc) { 3055 ip6_sprintf(sp, &inc->inc6_faddr); 3056 sp = s + strlen(s); 3057 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport)); 3058 sp = s + strlen(s); 3059 ip6_sprintf(sp, &inc->inc6_laddr); 3060 sp = s + strlen(s); 3061 sprintf(sp, "]:%i", ntohs(inc->inc_lport)); 3062 } else if (ip6 && th) { 3063 ip6_sprintf(sp, &ip6->ip6_src); 3064 sp = s + strlen(s); 3065 sprintf(sp, "]:%i to [", ntohs(th->th_sport)); 3066 sp = s + strlen(s); 3067 ip6_sprintf(sp, &ip6->ip6_dst); 3068 sp = s + strlen(s); 3069 sprintf(sp, "]:%i", ntohs(th->th_dport)); 3070 #endif /* INET6 */ 3071 #ifdef INET 3072 } else if (ip && th) { 3073 inet_ntoa_r(ip->ip_src, sp); 3074 sp = s + strlen(s); 3075 sprintf(sp, "]:%i to [", ntohs(th->th_sport)); 3076 sp = s + strlen(s); 3077 inet_ntoa_r(ip->ip_dst, sp); 3078 sp = s + strlen(s); 3079 sprintf(sp, "]:%i", ntohs(th->th_dport)); 3080 #endif /* INET */ 3081 } else { 3082 free(s, M_TCPLOG); 3083 return (NULL); 3084 } 3085 sp = s + strlen(s); 3086 if (th) 3087 sprintf(sp, " tcpflags 0x%b", th->th_flags, PRINT_TH_FLAGS); 3088 if (*(s + size - 1) != '\0') 3089 panic("%s: string too long", __func__); 3090 return (s); 3091 } 3092 3093 /* 3094 * A subroutine which makes it easy to track TCP state changes with DTrace. 3095 * This function shouldn't be called for t_state initializations that don't 3096 * correspond to actual TCP state transitions. 3097 */ 3098 void 3099 tcp_state_change(struct tcpcb *tp, int newstate) 3100 { 3101 #if defined(KDTRACE_HOOKS) 3102 int pstate = tp->t_state; 3103 #endif 3104 3105 TCPSTATES_DEC(tp->t_state); 3106 TCPSTATES_INC(newstate); 3107 tp->t_state = newstate; 3108 TCP_PROBE6(state__change, NULL, tp, NULL, tp, NULL, pstate); 3109 } 3110