1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)tcp_subr.c 8.2 (Berkeley) 5/24/95 32 */ 33 34 #include <sys/cdefs.h> 35 __FBSDID("$FreeBSD$"); 36 37 #include "opt_inet.h" 38 #include "opt_inet6.h" 39 #include "opt_ipsec.h" 40 #include "opt_kern_tls.h" 41 #include "opt_tcpdebug.h" 42 43 #include <sys/param.h> 44 #include <sys/systm.h> 45 #include <sys/arb.h> 46 #include <sys/callout.h> 47 #include <sys/eventhandler.h> 48 #ifdef TCP_HHOOK 49 #include <sys/hhook.h> 50 #endif 51 #include <sys/kernel.h> 52 #ifdef TCP_HHOOK 53 #include <sys/khelp.h> 54 #endif 55 #ifdef KERN_TLS 56 #include <sys/ktls.h> 57 #endif 58 #include <sys/qmath.h> 59 #include <sys/stats.h> 60 #include <sys/sysctl.h> 61 #include <sys/jail.h> 62 #include <sys/malloc.h> 63 #include <sys/refcount.h> 64 #include <sys/mbuf.h> 65 #ifdef INET6 66 #include <sys/domain.h> 67 #endif 68 #include <sys/priv.h> 69 #include <sys/proc.h> 70 #include <sys/sdt.h> 71 #include <sys/socket.h> 72 #include <sys/socketvar.h> 73 #include <sys/protosw.h> 74 #include <sys/random.h> 75 76 #include <vm/uma.h> 77 78 #include <net/route.h> 79 #include <net/route/nhop.h> 80 #include <net/if.h> 81 #include <net/if_var.h> 82 #include <net/vnet.h> 83 84 #include <netinet/in.h> 85 #include <netinet/in_fib.h> 86 #include <netinet/in_kdtrace.h> 87 #include <netinet/in_pcb.h> 88 #include <netinet/in_systm.h> 89 #include <netinet/in_var.h> 90 #include <netinet/ip.h> 91 #include <netinet/ip_icmp.h> 92 #include <netinet/ip_var.h> 93 #ifdef INET6 94 #include <netinet/icmp6.h> 95 #include <netinet/ip6.h> 96 #include <netinet6/in6_fib.h> 97 #include <netinet6/in6_pcb.h> 98 #include <netinet6/ip6_var.h> 99 #include <netinet6/scope6_var.h> 100 #include <netinet6/nd6.h> 101 #endif 102 103 #include <netinet/tcp.h> 104 #ifdef INVARIANTS 105 #define TCPSTATES 106 #endif 107 #include <netinet/tcp_fsm.h> 108 #include <netinet/tcp_seq.h> 109 #include <netinet/tcp_timer.h> 110 #include <netinet/tcp_var.h> 111 #include <netinet/tcp_log_buf.h> 112 #include <netinet/tcp_syncache.h> 113 #include <netinet/tcp_hpts.h> 114 #include <netinet/cc/cc.h> 115 #ifdef INET6 116 #include <netinet6/tcp6_var.h> 117 #endif 118 #include <netinet/tcpip.h> 119 #include <netinet/tcp_fastopen.h> 120 #ifdef TCPPCAP 121 #include <netinet/tcp_pcap.h> 122 #endif 123 #ifdef TCPDEBUG 124 #include <netinet/tcp_debug.h> 125 #endif 126 #ifdef INET6 127 #include <netinet6/ip6protosw.h> 128 #endif 129 #ifdef TCP_OFFLOAD 130 #include <netinet/tcp_offload.h> 131 #endif 132 #include <netinet/udp.h> 133 #include <netinet/udp_var.h> 134 135 #include <netipsec/ipsec_support.h> 136 137 #include <machine/in_cksum.h> 138 #include <crypto/siphash/siphash.h> 139 140 #include <security/mac/mac_framework.h> 141 142 VNET_DEFINE(int, tcp_mssdflt) = TCP_MSS; 143 #ifdef INET6 144 VNET_DEFINE(int, tcp_v6mssdflt) = TCP6_MSS; 145 #endif 146 147 #ifdef NETFLIX_EXP_DETECTION 148 /* Sack attack detection thresholds and such */ 149 SYSCTL_NODE(_net_inet_tcp, OID_AUTO, sack_attack, 150 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 151 "Sack Attack detection thresholds"); 152 int32_t tcp_force_detection = 0; 153 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, force_detection, 154 CTLFLAG_RW, 155 &tcp_force_detection, 0, 156 "Do we force detection even if the INP has it off?"); 157 int32_t tcp_sack_to_ack_thresh = 700; /* 70 % */ 158 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, sack_to_ack_thresh, 159 CTLFLAG_RW, 160 &tcp_sack_to_ack_thresh, 700, 161 "Percentage of sacks to acks we must see above (10.1 percent is 101)?"); 162 int32_t tcp_sack_to_move_thresh = 600; /* 60 % */ 163 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, move_thresh, 164 CTLFLAG_RW, 165 &tcp_sack_to_move_thresh, 600, 166 "Percentage of sack moves we must see above (10.1 percent is 101)"); 167 int32_t tcp_restoral_thresh = 650; /* 65 % (sack:2:ack -5%) */ 168 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, restore_thresh, 169 CTLFLAG_RW, 170 &tcp_restoral_thresh, 550, 171 "Percentage of sack to ack percentage we must see below to restore(10.1 percent is 101)"); 172 int32_t tcp_sad_decay_val = 800; 173 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, decay_per, 174 CTLFLAG_RW, 175 &tcp_sad_decay_val, 800, 176 "The decay percentage (10.1 percent equals 101 )"); 177 int32_t tcp_map_minimum = 500; 178 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, nummaps, 179 CTLFLAG_RW, 180 &tcp_map_minimum, 500, 181 "Number of Map enteries before we start detection"); 182 int32_t tcp_attack_on_turns_on_logging = 0; 183 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, attacks_logged, 184 CTLFLAG_RW, 185 &tcp_attack_on_turns_on_logging, 0, 186 "When we have a positive hit on attack, do we turn on logging?"); 187 int32_t tcp_sad_pacing_interval = 2000; 188 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, sad_pacing_int, 189 CTLFLAG_RW, 190 &tcp_sad_pacing_interval, 2000, 191 "What is the minimum pacing interval for a classified attacker?"); 192 193 int32_t tcp_sad_low_pps = 100; 194 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, sad_low_pps, 195 CTLFLAG_RW, 196 &tcp_sad_low_pps, 100, 197 "What is the input pps that below which we do not decay?"); 198 #endif 199 uint32_t tcp_ack_war_time_window = 1000; 200 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, ack_war_timewindow, 201 CTLFLAG_RW, 202 &tcp_ack_war_time_window, 1000, 203 "If the tcp_stack does ack-war prevention how many milliseconds are in its time window?"); 204 uint32_t tcp_ack_war_cnt = 5; 205 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, ack_war_cnt, 206 CTLFLAG_RW, 207 &tcp_ack_war_cnt, 5, 208 "If the tcp_stack does ack-war prevention how many acks can be sent in its time window?"); 209 210 struct rwlock tcp_function_lock; 211 212 static int 213 sysctl_net_inet_tcp_mss_check(SYSCTL_HANDLER_ARGS) 214 { 215 int error, new; 216 217 new = V_tcp_mssdflt; 218 error = sysctl_handle_int(oidp, &new, 0, req); 219 if (error == 0 && req->newptr) { 220 if (new < TCP_MINMSS) 221 error = EINVAL; 222 else 223 V_tcp_mssdflt = new; 224 } 225 return (error); 226 } 227 228 SYSCTL_PROC(_net_inet_tcp, TCPCTL_MSSDFLT, mssdflt, 229 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 230 &VNET_NAME(tcp_mssdflt), 0, &sysctl_net_inet_tcp_mss_check, "I", 231 "Default TCP Maximum Segment Size"); 232 233 #ifdef INET6 234 static int 235 sysctl_net_inet_tcp_mss_v6_check(SYSCTL_HANDLER_ARGS) 236 { 237 int error, new; 238 239 new = V_tcp_v6mssdflt; 240 error = sysctl_handle_int(oidp, &new, 0, req); 241 if (error == 0 && req->newptr) { 242 if (new < TCP_MINMSS) 243 error = EINVAL; 244 else 245 V_tcp_v6mssdflt = new; 246 } 247 return (error); 248 } 249 250 SYSCTL_PROC(_net_inet_tcp, TCPCTL_V6MSSDFLT, v6mssdflt, 251 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 252 &VNET_NAME(tcp_v6mssdflt), 0, &sysctl_net_inet_tcp_mss_v6_check, "I", 253 "Default TCP Maximum Segment Size for IPv6"); 254 #endif /* INET6 */ 255 256 /* 257 * Minimum MSS we accept and use. This prevents DoS attacks where 258 * we are forced to a ridiculous low MSS like 20 and send hundreds 259 * of packets instead of one. The effect scales with the available 260 * bandwidth and quickly saturates the CPU and network interface 261 * with packet generation and sending. Set to zero to disable MINMSS 262 * checking. This setting prevents us from sending too small packets. 263 */ 264 VNET_DEFINE(int, tcp_minmss) = TCP_MINMSS; 265 SYSCTL_INT(_net_inet_tcp, OID_AUTO, minmss, CTLFLAG_VNET | CTLFLAG_RW, 266 &VNET_NAME(tcp_minmss), 0, 267 "Minimum TCP Maximum Segment Size"); 268 269 VNET_DEFINE(int, tcp_do_rfc1323) = 1; 270 SYSCTL_INT(_net_inet_tcp, TCPCTL_DO_RFC1323, rfc1323, CTLFLAG_VNET | CTLFLAG_RW, 271 &VNET_NAME(tcp_do_rfc1323), 0, 272 "Enable rfc1323 (high performance TCP) extensions"); 273 274 /* 275 * As of June 2021, several TCP stacks violate RFC 7323 from September 2014. 276 * Some stacks negotiate TS, but never send them after connection setup. Some 277 * stacks negotiate TS, but don't send them when sending keep-alive segments. 278 * These include modern widely deployed TCP stacks. 279 * Therefore tolerating violations for now... 280 */ 281 VNET_DEFINE(int, tcp_tolerate_missing_ts) = 1; 282 SYSCTL_INT(_net_inet_tcp, OID_AUTO, tolerate_missing_ts, CTLFLAG_VNET | CTLFLAG_RW, 283 &VNET_NAME(tcp_tolerate_missing_ts), 0, 284 "Tolerate missing TCP timestamps"); 285 286 VNET_DEFINE(int, tcp_ts_offset_per_conn) = 1; 287 SYSCTL_INT(_net_inet_tcp, OID_AUTO, ts_offset_per_conn, CTLFLAG_VNET | CTLFLAG_RW, 288 &VNET_NAME(tcp_ts_offset_per_conn), 0, 289 "Initialize TCP timestamps per connection instead of per host pair"); 290 291 /* How many connections are pacing */ 292 static volatile uint32_t number_of_tcp_connections_pacing = 0; 293 static uint32_t shadow_num_connections = 0; 294 295 static int tcp_pacing_limit = 10000; 296 SYSCTL_INT(_net_inet_tcp, OID_AUTO, pacing_limit, CTLFLAG_RW, 297 &tcp_pacing_limit, 1000, 298 "If the TCP stack does pacing, is there a limit (-1 = no, 0 = no pacing N = number of connections)"); 299 300 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, pacing_count, CTLFLAG_RD, 301 &shadow_num_connections, 0, "Number of TCP connections being paced"); 302 303 static int tcp_log_debug = 0; 304 SYSCTL_INT(_net_inet_tcp, OID_AUTO, log_debug, CTLFLAG_RW, 305 &tcp_log_debug, 0, "Log errors caused by incoming TCP segments"); 306 307 static int tcp_tcbhashsize; 308 SYSCTL_INT(_net_inet_tcp, OID_AUTO, tcbhashsize, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, 309 &tcp_tcbhashsize, 0, "Size of TCP control-block hashtable"); 310 311 static int do_tcpdrain = 1; 312 SYSCTL_INT(_net_inet_tcp, OID_AUTO, do_tcpdrain, CTLFLAG_RW, &do_tcpdrain, 0, 313 "Enable tcp_drain routine for extra help when low on mbufs"); 314 315 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, pcbcount, CTLFLAG_VNET | CTLFLAG_RD, 316 &VNET_NAME(tcbinfo.ipi_count), 0, "Number of active PCBs"); 317 318 VNET_DEFINE_STATIC(int, icmp_may_rst) = 1; 319 #define V_icmp_may_rst VNET(icmp_may_rst) 320 SYSCTL_INT(_net_inet_tcp, OID_AUTO, icmp_may_rst, CTLFLAG_VNET | CTLFLAG_RW, 321 &VNET_NAME(icmp_may_rst), 0, 322 "Certain ICMP unreachable messages may abort connections in SYN_SENT"); 323 324 VNET_DEFINE_STATIC(int, tcp_isn_reseed_interval) = 0; 325 #define V_tcp_isn_reseed_interval VNET(tcp_isn_reseed_interval) 326 SYSCTL_INT(_net_inet_tcp, OID_AUTO, isn_reseed_interval, CTLFLAG_VNET | CTLFLAG_RW, 327 &VNET_NAME(tcp_isn_reseed_interval), 0, 328 "Seconds between reseeding of ISN secret"); 329 330 static int tcp_soreceive_stream; 331 SYSCTL_INT(_net_inet_tcp, OID_AUTO, soreceive_stream, CTLFLAG_RDTUN, 332 &tcp_soreceive_stream, 0, "Using soreceive_stream for TCP sockets"); 333 334 VNET_DEFINE(uma_zone_t, sack_hole_zone); 335 #define V_sack_hole_zone VNET(sack_hole_zone) 336 VNET_DEFINE(uint32_t, tcp_map_entries_limit) = 0; /* unlimited */ 337 static int 338 sysctl_net_inet_tcp_map_limit_check(SYSCTL_HANDLER_ARGS) 339 { 340 int error; 341 uint32_t new; 342 343 new = V_tcp_map_entries_limit; 344 error = sysctl_handle_int(oidp, &new, 0, req); 345 if (error == 0 && req->newptr) { 346 /* only allow "0" and value > minimum */ 347 if (new > 0 && new < TCP_MIN_MAP_ENTRIES_LIMIT) 348 error = EINVAL; 349 else 350 V_tcp_map_entries_limit = new; 351 } 352 return (error); 353 } 354 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, map_limit, 355 CTLFLAG_VNET | CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 356 &VNET_NAME(tcp_map_entries_limit), 0, 357 &sysctl_net_inet_tcp_map_limit_check, "IU", 358 "Total sendmap entries limit"); 359 360 VNET_DEFINE(uint32_t, tcp_map_split_limit) = 0; /* unlimited */ 361 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, split_limit, CTLFLAG_VNET | CTLFLAG_RW, 362 &VNET_NAME(tcp_map_split_limit), 0, 363 "Total sendmap split entries limit"); 364 365 #ifdef TCP_HHOOK 366 VNET_DEFINE(struct hhook_head *, tcp_hhh[HHOOK_TCP_LAST+1]); 367 #endif 368 369 #define TS_OFFSET_SECRET_LENGTH SIPHASH_KEY_LENGTH 370 VNET_DEFINE_STATIC(u_char, ts_offset_secret[TS_OFFSET_SECRET_LENGTH]); 371 #define V_ts_offset_secret VNET(ts_offset_secret) 372 373 static int tcp_default_fb_init(struct tcpcb *tp); 374 static void tcp_default_fb_fini(struct tcpcb *tp, int tcb_is_purged); 375 static int tcp_default_handoff_ok(struct tcpcb *tp); 376 static struct inpcb *tcp_notify(struct inpcb *, int); 377 static struct inpcb *tcp_mtudisc_notify(struct inpcb *, int); 378 static struct inpcb *tcp_mtudisc(struct inpcb *, int); 379 static char * tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th, 380 void *ip4hdr, const void *ip6hdr); 381 382 static struct tcp_function_block tcp_def_funcblk = { 383 .tfb_tcp_block_name = "freebsd", 384 .tfb_tcp_output = tcp_default_output, 385 .tfb_tcp_do_segment = tcp_do_segment, 386 .tfb_tcp_ctloutput = tcp_default_ctloutput, 387 .tfb_tcp_handoff_ok = tcp_default_handoff_ok, 388 .tfb_tcp_fb_init = tcp_default_fb_init, 389 .tfb_tcp_fb_fini = tcp_default_fb_fini, 390 }; 391 392 static int tcp_fb_cnt = 0; 393 struct tcp_funchead t_functions; 394 static struct tcp_function_block *tcp_func_set_ptr = &tcp_def_funcblk; 395 396 void 397 tcp_record_dsack(struct tcpcb *tp, tcp_seq start, tcp_seq end, int tlp) 398 { 399 TCPSTAT_INC(tcps_dsack_count); 400 tp->t_dsack_pack++; 401 if (tlp == 0) { 402 if (SEQ_GT(end, start)) { 403 tp->t_dsack_bytes += (end - start); 404 TCPSTAT_ADD(tcps_dsack_bytes, (end - start)); 405 } else { 406 tp->t_dsack_tlp_bytes += (start - end); 407 TCPSTAT_ADD(tcps_dsack_bytes, (start - end)); 408 } 409 } else { 410 if (SEQ_GT(end, start)) { 411 tp->t_dsack_bytes += (end - start); 412 TCPSTAT_ADD(tcps_dsack_tlp_bytes, (end - start)); 413 } else { 414 tp->t_dsack_tlp_bytes += (start - end); 415 TCPSTAT_ADD(tcps_dsack_tlp_bytes, (start - end)); 416 } 417 } 418 } 419 420 static struct tcp_function_block * 421 find_tcp_functions_locked(struct tcp_function_set *fs) 422 { 423 struct tcp_function *f; 424 struct tcp_function_block *blk=NULL; 425 426 TAILQ_FOREACH(f, &t_functions, tf_next) { 427 if (strcmp(f->tf_name, fs->function_set_name) == 0) { 428 blk = f->tf_fb; 429 break; 430 } 431 } 432 return(blk); 433 } 434 435 static struct tcp_function_block * 436 find_tcp_fb_locked(struct tcp_function_block *blk, struct tcp_function **s) 437 { 438 struct tcp_function_block *rblk=NULL; 439 struct tcp_function *f; 440 441 TAILQ_FOREACH(f, &t_functions, tf_next) { 442 if (f->tf_fb == blk) { 443 rblk = blk; 444 if (s) { 445 *s = f; 446 } 447 break; 448 } 449 } 450 return (rblk); 451 } 452 453 struct tcp_function_block * 454 find_and_ref_tcp_functions(struct tcp_function_set *fs) 455 { 456 struct tcp_function_block *blk; 457 458 rw_rlock(&tcp_function_lock); 459 blk = find_tcp_functions_locked(fs); 460 if (blk) 461 refcount_acquire(&blk->tfb_refcnt); 462 rw_runlock(&tcp_function_lock); 463 return(blk); 464 } 465 466 struct tcp_function_block * 467 find_and_ref_tcp_fb(struct tcp_function_block *blk) 468 { 469 struct tcp_function_block *rblk; 470 471 rw_rlock(&tcp_function_lock); 472 rblk = find_tcp_fb_locked(blk, NULL); 473 if (rblk) 474 refcount_acquire(&rblk->tfb_refcnt); 475 rw_runlock(&tcp_function_lock); 476 return(rblk); 477 } 478 479 /* Find a matching alias for the given tcp_function_block. */ 480 int 481 find_tcp_function_alias(struct tcp_function_block *blk, 482 struct tcp_function_set *fs) 483 { 484 struct tcp_function *f; 485 int found; 486 487 found = 0; 488 rw_rlock(&tcp_function_lock); 489 TAILQ_FOREACH(f, &t_functions, tf_next) { 490 if ((f->tf_fb == blk) && 491 (strncmp(f->tf_name, blk->tfb_tcp_block_name, 492 TCP_FUNCTION_NAME_LEN_MAX) != 0)) { 493 /* Matching function block with different name. */ 494 strncpy(fs->function_set_name, f->tf_name, 495 TCP_FUNCTION_NAME_LEN_MAX); 496 found = 1; 497 break; 498 } 499 } 500 /* Null terminate the string appropriately. */ 501 if (found) { 502 fs->function_set_name[TCP_FUNCTION_NAME_LEN_MAX - 1] = '\0'; 503 } else { 504 fs->function_set_name[0] = '\0'; 505 } 506 rw_runlock(&tcp_function_lock); 507 return (found); 508 } 509 510 static struct tcp_function_block * 511 find_and_ref_tcp_default_fb(void) 512 { 513 struct tcp_function_block *rblk; 514 515 rw_rlock(&tcp_function_lock); 516 rblk = tcp_func_set_ptr; 517 refcount_acquire(&rblk->tfb_refcnt); 518 rw_runlock(&tcp_function_lock); 519 return (rblk); 520 } 521 522 void 523 tcp_switch_back_to_default(struct tcpcb *tp) 524 { 525 struct tcp_function_block *tfb; 526 527 KASSERT(tp->t_fb != &tcp_def_funcblk, 528 ("%s: called by the built-in default stack", __func__)); 529 530 /* 531 * Release the old stack. This function will either find a new one 532 * or panic. 533 */ 534 if (tp->t_fb->tfb_tcp_fb_fini != NULL) 535 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 0); 536 refcount_release(&tp->t_fb->tfb_refcnt); 537 538 /* 539 * Now, we'll find a new function block to use. 540 * Start by trying the current user-selected 541 * default, unless this stack is the user-selected 542 * default. 543 */ 544 tfb = find_and_ref_tcp_default_fb(); 545 if (tfb == tp->t_fb) { 546 refcount_release(&tfb->tfb_refcnt); 547 tfb = NULL; 548 } 549 /* Does the stack accept this connection? */ 550 if (tfb != NULL && tfb->tfb_tcp_handoff_ok != NULL && 551 (*tfb->tfb_tcp_handoff_ok)(tp)) { 552 refcount_release(&tfb->tfb_refcnt); 553 tfb = NULL; 554 } 555 /* Try to use that stack. */ 556 if (tfb != NULL) { 557 /* Initialize the new stack. If it succeeds, we are done. */ 558 tp->t_fb = tfb; 559 if (tp->t_fb->tfb_tcp_fb_init == NULL || 560 (*tp->t_fb->tfb_tcp_fb_init)(tp) == 0) 561 return; 562 563 /* 564 * Initialization failed. Release the reference count on 565 * the stack. 566 */ 567 refcount_release(&tfb->tfb_refcnt); 568 } 569 570 /* 571 * If that wasn't feasible, use the built-in default 572 * stack which is not allowed to reject anyone. 573 */ 574 tfb = find_and_ref_tcp_fb(&tcp_def_funcblk); 575 if (tfb == NULL) { 576 /* there always should be a default */ 577 panic("Can't refer to tcp_def_funcblk"); 578 } 579 if (tfb->tfb_tcp_handoff_ok != NULL) { 580 if ((*tfb->tfb_tcp_handoff_ok) (tp)) { 581 /* The default stack cannot say no */ 582 panic("Default stack rejects a new session?"); 583 } 584 } 585 tp->t_fb = tfb; 586 if (tp->t_fb->tfb_tcp_fb_init != NULL && 587 (*tp->t_fb->tfb_tcp_fb_init)(tp)) { 588 /* The default stack cannot fail */ 589 panic("Default stack initialization failed"); 590 } 591 } 592 593 static void 594 tcp_recv_udp_tunneled_packet(struct mbuf *m, int off, struct inpcb *inp, 595 const struct sockaddr *sa, void *ctx) 596 { 597 struct ip *iph; 598 #ifdef INET6 599 struct ip6_hdr *ip6; 600 #endif 601 struct udphdr *uh; 602 struct tcphdr *th; 603 int thlen; 604 uint16_t port; 605 606 TCPSTAT_INC(tcps_tunneled_pkts); 607 if ((m->m_flags & M_PKTHDR) == 0) { 608 /* Can't handle one that is not a pkt hdr */ 609 TCPSTAT_INC(tcps_tunneled_errs); 610 goto out; 611 } 612 thlen = sizeof(struct tcphdr); 613 if (m->m_len < off + sizeof(struct udphdr) + thlen && 614 (m = m_pullup(m, off + sizeof(struct udphdr) + thlen)) == NULL) { 615 TCPSTAT_INC(tcps_tunneled_errs); 616 goto out; 617 } 618 iph = mtod(m, struct ip *); 619 uh = (struct udphdr *)((caddr_t)iph + off); 620 th = (struct tcphdr *)(uh + 1); 621 thlen = th->th_off << 2; 622 if (m->m_len < off + sizeof(struct udphdr) + thlen) { 623 m = m_pullup(m, off + sizeof(struct udphdr) + thlen); 624 if (m == NULL) { 625 TCPSTAT_INC(tcps_tunneled_errs); 626 goto out; 627 } else { 628 iph = mtod(m, struct ip *); 629 uh = (struct udphdr *)((caddr_t)iph + off); 630 th = (struct tcphdr *)(uh + 1); 631 } 632 } 633 m->m_pkthdr.tcp_tun_port = port = uh->uh_sport; 634 bcopy(th, uh, m->m_len - off); 635 m->m_len -= sizeof(struct udphdr); 636 m->m_pkthdr.len -= sizeof(struct udphdr); 637 /* 638 * We use the same algorithm for 639 * both UDP and TCP for c-sum. So 640 * the code in tcp_input will skip 641 * the checksum. So we do nothing 642 * with the flag (m->m_pkthdr.csum_flags). 643 */ 644 switch (iph->ip_v) { 645 #ifdef INET 646 case IPVERSION: 647 iph->ip_len = htons(ntohs(iph->ip_len) - sizeof(struct udphdr)); 648 tcp_input_with_port(&m, &off, IPPROTO_TCP, port); 649 break; 650 #endif 651 #ifdef INET6 652 case IPV6_VERSION >> 4: 653 ip6 = mtod(m, struct ip6_hdr *); 654 ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - sizeof(struct udphdr)); 655 tcp6_input_with_port(&m, &off, IPPROTO_TCP, port); 656 break; 657 #endif 658 default: 659 goto out; 660 break; 661 } 662 return; 663 out: 664 m_freem(m); 665 } 666 667 static int 668 sysctl_net_inet_default_tcp_functions(SYSCTL_HANDLER_ARGS) 669 { 670 int error=ENOENT; 671 struct tcp_function_set fs; 672 struct tcp_function_block *blk; 673 674 memset(&fs, 0, sizeof(fs)); 675 rw_rlock(&tcp_function_lock); 676 blk = find_tcp_fb_locked(tcp_func_set_ptr, NULL); 677 if (blk) { 678 /* Found him */ 679 strcpy(fs.function_set_name, blk->tfb_tcp_block_name); 680 fs.pcbcnt = blk->tfb_refcnt; 681 } 682 rw_runlock(&tcp_function_lock); 683 error = sysctl_handle_string(oidp, fs.function_set_name, 684 sizeof(fs.function_set_name), req); 685 686 /* Check for error or no change */ 687 if (error != 0 || req->newptr == NULL) 688 return(error); 689 690 rw_wlock(&tcp_function_lock); 691 blk = find_tcp_functions_locked(&fs); 692 if ((blk == NULL) || 693 (blk->tfb_flags & TCP_FUNC_BEING_REMOVED)) { 694 error = ENOENT; 695 goto done; 696 } 697 tcp_func_set_ptr = blk; 698 done: 699 rw_wunlock(&tcp_function_lock); 700 return (error); 701 } 702 703 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, functions_default, 704 CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 705 NULL, 0, sysctl_net_inet_default_tcp_functions, "A", 706 "Set/get the default TCP functions"); 707 708 static int 709 sysctl_net_inet_list_available(SYSCTL_HANDLER_ARGS) 710 { 711 int error, cnt, linesz; 712 struct tcp_function *f; 713 char *buffer, *cp; 714 size_t bufsz, outsz; 715 bool alias; 716 717 cnt = 0; 718 rw_rlock(&tcp_function_lock); 719 TAILQ_FOREACH(f, &t_functions, tf_next) { 720 cnt++; 721 } 722 rw_runlock(&tcp_function_lock); 723 724 bufsz = (cnt+2) * ((TCP_FUNCTION_NAME_LEN_MAX * 2) + 13) + 1; 725 buffer = malloc(bufsz, M_TEMP, M_WAITOK); 726 727 error = 0; 728 cp = buffer; 729 730 linesz = snprintf(cp, bufsz, "\n%-32s%c %-32s %s\n", "Stack", 'D', 731 "Alias", "PCB count"); 732 cp += linesz; 733 bufsz -= linesz; 734 outsz = linesz; 735 736 rw_rlock(&tcp_function_lock); 737 TAILQ_FOREACH(f, &t_functions, tf_next) { 738 alias = (f->tf_name != f->tf_fb->tfb_tcp_block_name); 739 linesz = snprintf(cp, bufsz, "%-32s%c %-32s %u\n", 740 f->tf_fb->tfb_tcp_block_name, 741 (f->tf_fb == tcp_func_set_ptr) ? '*' : ' ', 742 alias ? f->tf_name : "-", 743 f->tf_fb->tfb_refcnt); 744 if (linesz >= bufsz) { 745 error = EOVERFLOW; 746 break; 747 } 748 cp += linesz; 749 bufsz -= linesz; 750 outsz += linesz; 751 } 752 rw_runlock(&tcp_function_lock); 753 if (error == 0) 754 error = sysctl_handle_string(oidp, buffer, outsz + 1, req); 755 free(buffer, M_TEMP); 756 return (error); 757 } 758 759 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, functions_available, 760 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT, 761 NULL, 0, sysctl_net_inet_list_available, "A", 762 "list available TCP Function sets"); 763 764 VNET_DEFINE(int, tcp_udp_tunneling_port) = TCP_TUNNELING_PORT_DEFAULT; 765 766 #ifdef INET 767 VNET_DEFINE(struct socket *, udp4_tun_socket) = NULL; 768 #define V_udp4_tun_socket VNET(udp4_tun_socket) 769 #endif 770 #ifdef INET6 771 VNET_DEFINE(struct socket *, udp6_tun_socket) = NULL; 772 #define V_udp6_tun_socket VNET(udp6_tun_socket) 773 #endif 774 775 static void 776 tcp_over_udp_stop(void) 777 { 778 /* 779 * This function assumes sysctl caller holds inp_rinfo_lock() 780 * for writing! 781 */ 782 #ifdef INET 783 if (V_udp4_tun_socket != NULL) { 784 soclose(V_udp4_tun_socket); 785 V_udp4_tun_socket = NULL; 786 } 787 #endif 788 #ifdef INET6 789 if (V_udp6_tun_socket != NULL) { 790 soclose(V_udp6_tun_socket); 791 V_udp6_tun_socket = NULL; 792 } 793 #endif 794 } 795 796 static int 797 tcp_over_udp_start(void) 798 { 799 uint16_t port; 800 int ret; 801 #ifdef INET 802 struct sockaddr_in sin; 803 #endif 804 #ifdef INET6 805 struct sockaddr_in6 sin6; 806 #endif 807 /* 808 * This function assumes sysctl caller holds inp_info_rlock() 809 * for writing! 810 */ 811 port = V_tcp_udp_tunneling_port; 812 if (ntohs(port) == 0) { 813 /* Must have a port set */ 814 return (EINVAL); 815 } 816 #ifdef INET 817 if (V_udp4_tun_socket != NULL) { 818 /* Already running -- must stop first */ 819 return (EALREADY); 820 } 821 #endif 822 #ifdef INET6 823 if (V_udp6_tun_socket != NULL) { 824 /* Already running -- must stop first */ 825 return (EALREADY); 826 } 827 #endif 828 #ifdef INET 829 if ((ret = socreate(PF_INET, &V_udp4_tun_socket, 830 SOCK_DGRAM, IPPROTO_UDP, 831 curthread->td_ucred, curthread))) { 832 tcp_over_udp_stop(); 833 return (ret); 834 } 835 /* Call the special UDP hook. */ 836 if ((ret = udp_set_kernel_tunneling(V_udp4_tun_socket, 837 tcp_recv_udp_tunneled_packet, 838 tcp_ctlinput_viaudp, 839 NULL))) { 840 tcp_over_udp_stop(); 841 return (ret); 842 } 843 /* Ok, we have a socket, bind it to the port. */ 844 memset(&sin, 0, sizeof(struct sockaddr_in)); 845 sin.sin_len = sizeof(struct sockaddr_in); 846 sin.sin_family = AF_INET; 847 sin.sin_port = htons(port); 848 if ((ret = sobind(V_udp4_tun_socket, 849 (struct sockaddr *)&sin, curthread))) { 850 tcp_over_udp_stop(); 851 return (ret); 852 } 853 #endif 854 #ifdef INET6 855 if ((ret = socreate(PF_INET6, &V_udp6_tun_socket, 856 SOCK_DGRAM, IPPROTO_UDP, 857 curthread->td_ucred, curthread))) { 858 tcp_over_udp_stop(); 859 return (ret); 860 } 861 /* Call the special UDP hook. */ 862 if ((ret = udp_set_kernel_tunneling(V_udp6_tun_socket, 863 tcp_recv_udp_tunneled_packet, 864 tcp6_ctlinput_viaudp, 865 NULL))) { 866 tcp_over_udp_stop(); 867 return (ret); 868 } 869 /* Ok, we have a socket, bind it to the port. */ 870 memset(&sin6, 0, sizeof(struct sockaddr_in6)); 871 sin6.sin6_len = sizeof(struct sockaddr_in6); 872 sin6.sin6_family = AF_INET6; 873 sin6.sin6_port = htons(port); 874 if ((ret = sobind(V_udp6_tun_socket, 875 (struct sockaddr *)&sin6, curthread))) { 876 tcp_over_udp_stop(); 877 return (ret); 878 } 879 #endif 880 return (0); 881 } 882 883 static int 884 sysctl_net_inet_tcp_udp_tunneling_port_check(SYSCTL_HANDLER_ARGS) 885 { 886 int error; 887 uint32_t old, new; 888 889 old = V_tcp_udp_tunneling_port; 890 new = old; 891 error = sysctl_handle_int(oidp, &new, 0, req); 892 if ((error == 0) && 893 (req->newptr != NULL)) { 894 if ((new < TCP_TUNNELING_PORT_MIN) || 895 (new > TCP_TUNNELING_PORT_MAX)) { 896 error = EINVAL; 897 } else { 898 V_tcp_udp_tunneling_port = new; 899 if (old != 0) { 900 tcp_over_udp_stop(); 901 } 902 if (new != 0) { 903 error = tcp_over_udp_start(); 904 } 905 } 906 } 907 return (error); 908 } 909 910 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, udp_tunneling_port, 911 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 912 &VNET_NAME(tcp_udp_tunneling_port), 913 0, &sysctl_net_inet_tcp_udp_tunneling_port_check, "IU", 914 "Tunneling port for tcp over udp"); 915 916 VNET_DEFINE(int, tcp_udp_tunneling_overhead) = TCP_TUNNELING_OVERHEAD_DEFAULT; 917 918 static int 919 sysctl_net_inet_tcp_udp_tunneling_overhead_check(SYSCTL_HANDLER_ARGS) 920 { 921 int error, new; 922 923 new = V_tcp_udp_tunneling_overhead; 924 error = sysctl_handle_int(oidp, &new, 0, req); 925 if (error == 0 && req->newptr) { 926 if ((new < TCP_TUNNELING_OVERHEAD_MIN) || 927 (new > TCP_TUNNELING_OVERHEAD_MAX)) 928 error = EINVAL; 929 else 930 V_tcp_udp_tunneling_overhead = new; 931 } 932 return (error); 933 } 934 935 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, udp_tunneling_overhead, 936 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 937 &VNET_NAME(tcp_udp_tunneling_overhead), 938 0, &sysctl_net_inet_tcp_udp_tunneling_overhead_check, "IU", 939 "MSS reduction when using tcp over udp"); 940 941 /* 942 * Exports one (struct tcp_function_info) for each alias/name. 943 */ 944 static int 945 sysctl_net_inet_list_func_info(SYSCTL_HANDLER_ARGS) 946 { 947 int cnt, error; 948 struct tcp_function *f; 949 struct tcp_function_info tfi; 950 951 /* 952 * We don't allow writes. 953 */ 954 if (req->newptr != NULL) 955 return (EINVAL); 956 957 /* 958 * Wire the old buffer so we can directly copy the functions to 959 * user space without dropping the lock. 960 */ 961 if (req->oldptr != NULL) { 962 error = sysctl_wire_old_buffer(req, 0); 963 if (error) 964 return (error); 965 } 966 967 /* 968 * Walk the list and copy out matching entries. If INVARIANTS 969 * is compiled in, also walk the list to verify the length of 970 * the list matches what we have recorded. 971 */ 972 rw_rlock(&tcp_function_lock); 973 974 cnt = 0; 975 #ifndef INVARIANTS 976 if (req->oldptr == NULL) { 977 cnt = tcp_fb_cnt; 978 goto skip_loop; 979 } 980 #endif 981 TAILQ_FOREACH(f, &t_functions, tf_next) { 982 #ifdef INVARIANTS 983 cnt++; 984 #endif 985 if (req->oldptr != NULL) { 986 bzero(&tfi, sizeof(tfi)); 987 tfi.tfi_refcnt = f->tf_fb->tfb_refcnt; 988 tfi.tfi_id = f->tf_fb->tfb_id; 989 (void)strlcpy(tfi.tfi_alias, f->tf_name, 990 sizeof(tfi.tfi_alias)); 991 (void)strlcpy(tfi.tfi_name, 992 f->tf_fb->tfb_tcp_block_name, sizeof(tfi.tfi_name)); 993 error = SYSCTL_OUT(req, &tfi, sizeof(tfi)); 994 /* 995 * Don't stop on error, as that is the 996 * mechanism we use to accumulate length 997 * information if the buffer was too short. 998 */ 999 } 1000 } 1001 KASSERT(cnt == tcp_fb_cnt, 1002 ("%s: cnt (%d) != tcp_fb_cnt (%d)", __func__, cnt, tcp_fb_cnt)); 1003 #ifndef INVARIANTS 1004 skip_loop: 1005 #endif 1006 rw_runlock(&tcp_function_lock); 1007 if (req->oldptr == NULL) 1008 error = SYSCTL_OUT(req, NULL, 1009 (cnt + 1) * sizeof(struct tcp_function_info)); 1010 1011 return (error); 1012 } 1013 1014 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, function_info, 1015 CTLTYPE_OPAQUE | CTLFLAG_SKIP | CTLFLAG_RD | CTLFLAG_MPSAFE, 1016 NULL, 0, sysctl_net_inet_list_func_info, "S,tcp_function_info", 1017 "List TCP function block name-to-ID mappings"); 1018 1019 /* 1020 * tfb_tcp_handoff_ok() function for the default stack. 1021 * Note that we'll basically try to take all comers. 1022 */ 1023 static int 1024 tcp_default_handoff_ok(struct tcpcb *tp) 1025 { 1026 1027 return (0); 1028 } 1029 1030 /* 1031 * tfb_tcp_fb_init() function for the default stack. 1032 * 1033 * This handles making sure we have appropriate timers set if you are 1034 * transitioning a socket that has some amount of setup done. 1035 * 1036 * The init() fuction from the default can *never* return non-zero i.e. 1037 * it is required to always succeed since it is the stack of last resort! 1038 */ 1039 static int 1040 tcp_default_fb_init(struct tcpcb *tp) 1041 { 1042 1043 struct socket *so; 1044 1045 INP_WLOCK_ASSERT(tp->t_inpcb); 1046 1047 KASSERT(tp->t_state >= 0 && tp->t_state < TCPS_TIME_WAIT, 1048 ("%s: connection %p in unexpected state %d", __func__, tp, 1049 tp->t_state)); 1050 1051 /* 1052 * Nothing to do for ESTABLISHED or LISTEN states. And, we don't 1053 * know what to do for unexpected states (which includes TIME_WAIT). 1054 */ 1055 if (tp->t_state <= TCPS_LISTEN || tp->t_state >= TCPS_TIME_WAIT) 1056 return (0); 1057 1058 /* 1059 * Make sure some kind of transmission timer is set if there is 1060 * outstanding data. 1061 */ 1062 so = tp->t_inpcb->inp_socket; 1063 if ((!TCPS_HAVEESTABLISHED(tp->t_state) || sbavail(&so->so_snd) || 1064 tp->snd_una != tp->snd_max) && !(tcp_timer_active(tp, TT_REXMT) || 1065 tcp_timer_active(tp, TT_PERSIST))) { 1066 /* 1067 * If the session has established and it looks like it should 1068 * be in the persist state, set the persist timer. Otherwise, 1069 * set the retransmit timer. 1070 */ 1071 if (TCPS_HAVEESTABLISHED(tp->t_state) && tp->snd_wnd == 0 && 1072 (int32_t)(tp->snd_nxt - tp->snd_una) < 1073 (int32_t)sbavail(&so->so_snd)) 1074 tcp_setpersist(tp); 1075 else 1076 tcp_timer_activate(tp, TT_REXMT, tp->t_rxtcur); 1077 } 1078 1079 /* All non-embryonic sessions get a keepalive timer. */ 1080 if (!tcp_timer_active(tp, TT_KEEP)) 1081 tcp_timer_activate(tp, TT_KEEP, 1082 TCPS_HAVEESTABLISHED(tp->t_state) ? TP_KEEPIDLE(tp) : 1083 TP_KEEPINIT(tp)); 1084 1085 /* 1086 * Make sure critical variables are initialized 1087 * if transitioning while in Recovery. 1088 */ 1089 if IN_FASTRECOVERY(tp->t_flags) { 1090 if (tp->sackhint.recover_fs == 0) 1091 tp->sackhint.recover_fs = max(1, 1092 tp->snd_nxt - tp->snd_una); 1093 } 1094 1095 return (0); 1096 } 1097 1098 /* 1099 * tfb_tcp_fb_fini() function for the default stack. 1100 * 1101 * This changes state as necessary (or prudent) to prepare for another stack 1102 * to assume responsibility for the connection. 1103 */ 1104 static void 1105 tcp_default_fb_fini(struct tcpcb *tp, int tcb_is_purged) 1106 { 1107 1108 INP_WLOCK_ASSERT(tp->t_inpcb); 1109 return; 1110 } 1111 1112 /* 1113 * Target size of TCP PCB hash tables. Must be a power of two. 1114 * 1115 * Note that this can be overridden by the kernel environment 1116 * variable net.inet.tcp.tcbhashsize 1117 */ 1118 #ifndef TCBHASHSIZE 1119 #define TCBHASHSIZE 0 1120 #endif 1121 1122 /* 1123 * XXX 1124 * Callouts should be moved into struct tcp directly. They are currently 1125 * separate because the tcpcb structure is exported to userland for sysctl 1126 * parsing purposes, which do not know about callouts. 1127 */ 1128 struct tcpcb_mem { 1129 struct tcpcb tcb; 1130 struct tcp_timer tt; 1131 struct cc_var ccv; 1132 #ifdef TCP_HHOOK 1133 struct osd osd; 1134 #endif 1135 }; 1136 1137 VNET_DEFINE_STATIC(uma_zone_t, tcpcb_zone); 1138 #define V_tcpcb_zone VNET(tcpcb_zone) 1139 1140 MALLOC_DEFINE(M_TCPLOG, "tcplog", "TCP address and flags print buffers"); 1141 MALLOC_DEFINE(M_TCPFUNCTIONS, "tcpfunc", "TCP function set memory"); 1142 1143 static struct mtx isn_mtx; 1144 1145 #define ISN_LOCK_INIT() mtx_init(&isn_mtx, "isn_mtx", NULL, MTX_DEF) 1146 #define ISN_LOCK() mtx_lock(&isn_mtx) 1147 #define ISN_UNLOCK() mtx_unlock(&isn_mtx) 1148 1149 INPCBSTORAGE_DEFINE(tcpcbstor, "tcpinp", "tcp_inpcb", "tcp", "tcphash"); 1150 1151 /* 1152 * Take a value and get the next power of 2 that doesn't overflow. 1153 * Used to size the tcp_inpcb hash buckets. 1154 */ 1155 static int 1156 maketcp_hashsize(int size) 1157 { 1158 int hashsize; 1159 1160 /* 1161 * auto tune. 1162 * get the next power of 2 higher than maxsockets. 1163 */ 1164 hashsize = 1 << fls(size); 1165 /* catch overflow, and just go one power of 2 smaller */ 1166 if (hashsize < size) { 1167 hashsize = 1 << (fls(size) - 1); 1168 } 1169 return (hashsize); 1170 } 1171 1172 static volatile int next_tcp_stack_id = 1; 1173 1174 /* 1175 * Register a TCP function block with the name provided in the names 1176 * array. (Note that this function does NOT automatically register 1177 * blk->tfb_tcp_block_name as a stack name. Therefore, you should 1178 * explicitly include blk->tfb_tcp_block_name in the list of names if 1179 * you wish to register the stack with that name.) 1180 * 1181 * Either all name registrations will succeed or all will fail. If 1182 * a name registration fails, the function will update the num_names 1183 * argument to point to the array index of the name that encountered 1184 * the failure. 1185 * 1186 * Returns 0 on success, or an error code on failure. 1187 */ 1188 int 1189 register_tcp_functions_as_names(struct tcp_function_block *blk, int wait, 1190 const char *names[], int *num_names) 1191 { 1192 struct tcp_function *n; 1193 struct tcp_function_set fs; 1194 int error, i; 1195 1196 KASSERT(names != NULL && *num_names > 0, 1197 ("%s: Called with 0-length name list", __func__)); 1198 KASSERT(names != NULL, ("%s: Called with NULL name list", __func__)); 1199 KASSERT(rw_initialized(&tcp_function_lock), 1200 ("%s: called too early", __func__)); 1201 1202 if ((blk->tfb_tcp_output == NULL) || 1203 (blk->tfb_tcp_do_segment == NULL) || 1204 (blk->tfb_tcp_ctloutput == NULL) || 1205 (strlen(blk->tfb_tcp_block_name) == 0)) { 1206 /* 1207 * These functions are required and you 1208 * need a name. 1209 */ 1210 *num_names = 0; 1211 return (EINVAL); 1212 } 1213 if (blk->tfb_tcp_timer_stop_all || 1214 blk->tfb_tcp_timer_activate || 1215 blk->tfb_tcp_timer_active || 1216 blk->tfb_tcp_timer_stop) { 1217 /* 1218 * If you define one timer function you 1219 * must have them all. 1220 */ 1221 if ((blk->tfb_tcp_timer_stop_all == NULL) || 1222 (blk->tfb_tcp_timer_activate == NULL) || 1223 (blk->tfb_tcp_timer_active == NULL) || 1224 (blk->tfb_tcp_timer_stop == NULL)) { 1225 *num_names = 0; 1226 return (EINVAL); 1227 } 1228 } 1229 1230 if (blk->tfb_flags & TCP_FUNC_BEING_REMOVED) { 1231 *num_names = 0; 1232 return (EINVAL); 1233 } 1234 1235 refcount_init(&blk->tfb_refcnt, 0); 1236 blk->tfb_id = atomic_fetchadd_int(&next_tcp_stack_id, 1); 1237 for (i = 0; i < *num_names; i++) { 1238 n = malloc(sizeof(struct tcp_function), M_TCPFUNCTIONS, wait); 1239 if (n == NULL) { 1240 error = ENOMEM; 1241 goto cleanup; 1242 } 1243 n->tf_fb = blk; 1244 1245 (void)strlcpy(fs.function_set_name, names[i], 1246 sizeof(fs.function_set_name)); 1247 rw_wlock(&tcp_function_lock); 1248 if (find_tcp_functions_locked(&fs) != NULL) { 1249 /* Duplicate name space not allowed */ 1250 rw_wunlock(&tcp_function_lock); 1251 free(n, M_TCPFUNCTIONS); 1252 error = EALREADY; 1253 goto cleanup; 1254 } 1255 (void)strlcpy(n->tf_name, names[i], sizeof(n->tf_name)); 1256 TAILQ_INSERT_TAIL(&t_functions, n, tf_next); 1257 tcp_fb_cnt++; 1258 rw_wunlock(&tcp_function_lock); 1259 } 1260 return(0); 1261 1262 cleanup: 1263 /* 1264 * Deregister the names we just added. Because registration failed 1265 * for names[i], we don't need to deregister that name. 1266 */ 1267 *num_names = i; 1268 rw_wlock(&tcp_function_lock); 1269 while (--i >= 0) { 1270 TAILQ_FOREACH(n, &t_functions, tf_next) { 1271 if (!strncmp(n->tf_name, names[i], 1272 TCP_FUNCTION_NAME_LEN_MAX)) { 1273 TAILQ_REMOVE(&t_functions, n, tf_next); 1274 tcp_fb_cnt--; 1275 n->tf_fb = NULL; 1276 free(n, M_TCPFUNCTIONS); 1277 break; 1278 } 1279 } 1280 } 1281 rw_wunlock(&tcp_function_lock); 1282 return (error); 1283 } 1284 1285 /* 1286 * Register a TCP function block using the name provided in the name 1287 * argument. 1288 * 1289 * Returns 0 on success, or an error code on failure. 1290 */ 1291 int 1292 register_tcp_functions_as_name(struct tcp_function_block *blk, const char *name, 1293 int wait) 1294 { 1295 const char *name_list[1]; 1296 int num_names, rv; 1297 1298 num_names = 1; 1299 if (name != NULL) 1300 name_list[0] = name; 1301 else 1302 name_list[0] = blk->tfb_tcp_block_name; 1303 rv = register_tcp_functions_as_names(blk, wait, name_list, &num_names); 1304 return (rv); 1305 } 1306 1307 /* 1308 * Register a TCP function block using the name defined in 1309 * blk->tfb_tcp_block_name. 1310 * 1311 * Returns 0 on success, or an error code on failure. 1312 */ 1313 int 1314 register_tcp_functions(struct tcp_function_block *blk, int wait) 1315 { 1316 1317 return (register_tcp_functions_as_name(blk, NULL, wait)); 1318 } 1319 1320 /* 1321 * Deregister all names associated with a function block. This 1322 * functionally removes the function block from use within the system. 1323 * 1324 * When called with a true quiesce argument, mark the function block 1325 * as being removed so no more stacks will use it and determine 1326 * whether the removal would succeed. 1327 * 1328 * When called with a false quiesce argument, actually attempt the 1329 * removal. 1330 * 1331 * When called with a force argument, attempt to switch all TCBs to 1332 * use the default stack instead of returning EBUSY. 1333 * 1334 * Returns 0 on success (or if the removal would succeed, or an error 1335 * code on failure. 1336 */ 1337 int 1338 deregister_tcp_functions(struct tcp_function_block *blk, bool quiesce, 1339 bool force) 1340 { 1341 struct tcp_function *f; 1342 1343 if (blk == &tcp_def_funcblk) { 1344 /* You can't un-register the default */ 1345 return (EPERM); 1346 } 1347 rw_wlock(&tcp_function_lock); 1348 if (blk == tcp_func_set_ptr) { 1349 /* You can't free the current default */ 1350 rw_wunlock(&tcp_function_lock); 1351 return (EBUSY); 1352 } 1353 /* Mark the block so no more stacks can use it. */ 1354 blk->tfb_flags |= TCP_FUNC_BEING_REMOVED; 1355 /* 1356 * If TCBs are still attached to the stack, attempt to switch them 1357 * to the default stack. 1358 */ 1359 if (force && blk->tfb_refcnt) { 1360 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, 1361 INPLOOKUP_WLOCKPCB); 1362 struct inpcb *inp; 1363 struct tcpcb *tp; 1364 VNET_ITERATOR_DECL(vnet_iter); 1365 1366 rw_wunlock(&tcp_function_lock); 1367 1368 VNET_LIST_RLOCK(); 1369 VNET_FOREACH(vnet_iter) { 1370 CURVNET_SET(vnet_iter); 1371 while ((inp = inp_next(&inpi)) != NULL) { 1372 if (inp->inp_flags & INP_TIMEWAIT) 1373 continue; 1374 tp = intotcpcb(inp); 1375 if (tp == NULL || tp->t_fb != blk) 1376 continue; 1377 tcp_switch_back_to_default(tp); 1378 } 1379 CURVNET_RESTORE(); 1380 } 1381 VNET_LIST_RUNLOCK(); 1382 1383 rw_wlock(&tcp_function_lock); 1384 } 1385 if (blk->tfb_refcnt) { 1386 /* TCBs still attached. */ 1387 rw_wunlock(&tcp_function_lock); 1388 return (EBUSY); 1389 } 1390 if (quiesce) { 1391 /* Skip removal. */ 1392 rw_wunlock(&tcp_function_lock); 1393 return (0); 1394 } 1395 /* Remove any function names that map to this function block. */ 1396 while (find_tcp_fb_locked(blk, &f) != NULL) { 1397 TAILQ_REMOVE(&t_functions, f, tf_next); 1398 tcp_fb_cnt--; 1399 f->tf_fb = NULL; 1400 free(f, M_TCPFUNCTIONS); 1401 } 1402 rw_wunlock(&tcp_function_lock); 1403 return (0); 1404 } 1405 1406 static void 1407 tcp_vnet_init(void *arg __unused) 1408 { 1409 1410 #ifdef TCP_HHOOK 1411 if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN, 1412 &V_tcp_hhh[HHOOK_TCP_EST_IN], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0) 1413 printf("%s: WARNING: unable to register helper hook\n", __func__); 1414 if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT, 1415 &V_tcp_hhh[HHOOK_TCP_EST_OUT], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0) 1416 printf("%s: WARNING: unable to register helper hook\n", __func__); 1417 #endif 1418 #ifdef STATS 1419 if (tcp_stats_init()) 1420 printf("%s: WARNING: unable to initialise TCP stats\n", 1421 __func__); 1422 #endif 1423 in_pcbinfo_init(&V_tcbinfo, &tcpcbstor, tcp_tcbhashsize, 1424 tcp_tcbhashsize); 1425 1426 /* 1427 * These have to be type stable for the benefit of the timers. 1428 */ 1429 V_tcpcb_zone = uma_zcreate("tcpcb", sizeof(struct tcpcb_mem), 1430 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 1431 uma_zone_set_max(V_tcpcb_zone, maxsockets); 1432 uma_zone_set_warning(V_tcpcb_zone, "kern.ipc.maxsockets limit reached"); 1433 1434 tcp_tw_init(); 1435 syncache_init(); 1436 tcp_hc_init(); 1437 1438 TUNABLE_INT_FETCH("net.inet.tcp.sack.enable", &V_tcp_do_sack); 1439 V_sack_hole_zone = uma_zcreate("sackhole", sizeof(struct sackhole), 1440 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 1441 1442 tcp_fastopen_init(); 1443 1444 COUNTER_ARRAY_ALLOC(V_tcps_states, TCP_NSTATES, M_WAITOK); 1445 VNET_PCPUSTAT_ALLOC(tcpstat, M_WAITOK); 1446 1447 V_tcp_msl = TCPTV_MSL; 1448 } 1449 VNET_SYSINIT(tcp_vnet_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, 1450 tcp_vnet_init, NULL); 1451 1452 static void 1453 tcp_init(void *arg __unused) 1454 { 1455 const char *tcbhash_tuneable; 1456 int hashsize; 1457 1458 tcp_reass_global_init(); 1459 1460 /* XXX virtualize those below? */ 1461 tcp_delacktime = TCPTV_DELACK; 1462 tcp_keepinit = TCPTV_KEEP_INIT; 1463 tcp_keepidle = TCPTV_KEEP_IDLE; 1464 tcp_keepintvl = TCPTV_KEEPINTVL; 1465 tcp_maxpersistidle = TCPTV_KEEP_IDLE; 1466 tcp_rexmit_initial = TCPTV_RTOBASE; 1467 if (tcp_rexmit_initial < 1) 1468 tcp_rexmit_initial = 1; 1469 tcp_rexmit_min = TCPTV_MIN; 1470 if (tcp_rexmit_min < 1) 1471 tcp_rexmit_min = 1; 1472 tcp_persmin = TCPTV_PERSMIN; 1473 tcp_persmax = TCPTV_PERSMAX; 1474 tcp_rexmit_slop = TCPTV_CPU_VAR; 1475 tcp_finwait2_timeout = TCPTV_FINWAIT2_TIMEOUT; 1476 1477 /* Setup the tcp function block list */ 1478 TAILQ_INIT(&t_functions); 1479 rw_init(&tcp_function_lock, "tcp_func_lock"); 1480 register_tcp_functions(&tcp_def_funcblk, M_WAITOK); 1481 #ifdef TCP_BLACKBOX 1482 /* Initialize the TCP logging data. */ 1483 tcp_log_init(); 1484 #endif 1485 arc4rand(&V_ts_offset_secret, sizeof(V_ts_offset_secret), 0); 1486 1487 if (tcp_soreceive_stream) { 1488 #ifdef INET 1489 tcp_usrreqs.pru_soreceive = soreceive_stream; 1490 #endif 1491 #ifdef INET6 1492 tcp6_usrreqs.pru_soreceive = soreceive_stream; 1493 #endif /* INET6 */ 1494 } 1495 1496 #ifdef INET6 1497 #define TCP_MINPROTOHDR (sizeof(struct ip6_hdr) + sizeof(struct tcphdr)) 1498 #else /* INET6 */ 1499 #define TCP_MINPROTOHDR (sizeof(struct tcpiphdr)) 1500 #endif /* INET6 */ 1501 if (max_protohdr < TCP_MINPROTOHDR) 1502 max_protohdr = TCP_MINPROTOHDR; 1503 if (max_linkhdr + TCP_MINPROTOHDR > MHLEN) 1504 panic("tcp_init"); 1505 #undef TCP_MINPROTOHDR 1506 1507 ISN_LOCK_INIT(); 1508 EVENTHANDLER_REGISTER(shutdown_pre_sync, tcp_fini, NULL, 1509 SHUTDOWN_PRI_DEFAULT); 1510 1511 tcp_inp_lro_direct_queue = counter_u64_alloc(M_WAITOK); 1512 tcp_inp_lro_wokeup_queue = counter_u64_alloc(M_WAITOK); 1513 tcp_inp_lro_compressed = counter_u64_alloc(M_WAITOK); 1514 tcp_inp_lro_locks_taken = counter_u64_alloc(M_WAITOK); 1515 tcp_extra_mbuf = counter_u64_alloc(M_WAITOK); 1516 tcp_would_have_but = counter_u64_alloc(M_WAITOK); 1517 tcp_comp_total = counter_u64_alloc(M_WAITOK); 1518 tcp_uncomp_total = counter_u64_alloc(M_WAITOK); 1519 tcp_bad_csums = counter_u64_alloc(M_WAITOK); 1520 #ifdef TCPPCAP 1521 tcp_pcap_init(); 1522 #endif 1523 1524 hashsize = TCBHASHSIZE; 1525 tcbhash_tuneable = "net.inet.tcp.tcbhashsize"; 1526 TUNABLE_INT_FETCH(tcbhash_tuneable, &hashsize); 1527 if (hashsize == 0) { 1528 /* 1529 * Auto tune the hash size based on maxsockets. 1530 * A perfect hash would have a 1:1 mapping 1531 * (hashsize = maxsockets) however it's been 1532 * suggested that O(2) average is better. 1533 */ 1534 hashsize = maketcp_hashsize(maxsockets / 4); 1535 /* 1536 * Our historical default is 512, 1537 * do not autotune lower than this. 1538 */ 1539 if (hashsize < 512) 1540 hashsize = 512; 1541 if (bootverbose) 1542 printf("%s: %s auto tuned to %d\n", __func__, 1543 tcbhash_tuneable, hashsize); 1544 } 1545 /* 1546 * We require a hashsize to be a power of two. 1547 * Previously if it was not a power of two we would just reset it 1548 * back to 512, which could be a nasty surprise if you did not notice 1549 * the error message. 1550 * Instead what we do is clip it to the closest power of two lower 1551 * than the specified hash value. 1552 */ 1553 if (!powerof2(hashsize)) { 1554 int oldhashsize = hashsize; 1555 1556 hashsize = maketcp_hashsize(hashsize); 1557 /* prevent absurdly low value */ 1558 if (hashsize < 16) 1559 hashsize = 16; 1560 printf("%s: WARNING: TCB hash size not a power of 2, " 1561 "clipped from %d to %d.\n", __func__, oldhashsize, 1562 hashsize); 1563 } 1564 tcp_tcbhashsize = hashsize; 1565 } 1566 SYSINIT(tcp_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, tcp_init, NULL); 1567 1568 #ifdef VIMAGE 1569 static void 1570 tcp_destroy(void *unused __unused) 1571 { 1572 int n; 1573 #ifdef TCP_HHOOK 1574 int error; 1575 #endif 1576 1577 /* 1578 * All our processes are gone, all our sockets should be cleaned 1579 * up, which means, we should be past the tcp_discardcb() calls. 1580 * Sleep to let all tcpcb timers really disappear and cleanup. 1581 */ 1582 for (;;) { 1583 INP_INFO_WLOCK(&V_tcbinfo); 1584 n = V_tcbinfo.ipi_count; 1585 INP_INFO_WUNLOCK(&V_tcbinfo); 1586 if (n == 0) 1587 break; 1588 pause("tcpdes", hz / 10); 1589 } 1590 tcp_hc_destroy(); 1591 syncache_destroy(); 1592 tcp_tw_destroy(); 1593 in_pcbinfo_destroy(&V_tcbinfo); 1594 /* tcp_discardcb() clears the sack_holes up. */ 1595 uma_zdestroy(V_sack_hole_zone); 1596 uma_zdestroy(V_tcpcb_zone); 1597 1598 /* 1599 * Cannot free the zone until all tcpcbs are released as we attach 1600 * the allocations to them. 1601 */ 1602 tcp_fastopen_destroy(); 1603 1604 COUNTER_ARRAY_FREE(V_tcps_states, TCP_NSTATES); 1605 VNET_PCPUSTAT_FREE(tcpstat); 1606 1607 #ifdef TCP_HHOOK 1608 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_IN]); 1609 if (error != 0) { 1610 printf("%s: WARNING: unable to deregister helper hook " 1611 "type=%d, id=%d: error %d returned\n", __func__, 1612 HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN, error); 1613 } 1614 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_OUT]); 1615 if (error != 0) { 1616 printf("%s: WARNING: unable to deregister helper hook " 1617 "type=%d, id=%d: error %d returned\n", __func__, 1618 HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT, error); 1619 } 1620 #endif 1621 } 1622 VNET_SYSUNINIT(tcp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, tcp_destroy, NULL); 1623 #endif 1624 1625 void 1626 tcp_fini(void *xtp) 1627 { 1628 1629 } 1630 1631 /* 1632 * Fill in the IP and TCP headers for an outgoing packet, given the tcpcb. 1633 * tcp_template used to store this data in mbufs, but we now recopy it out 1634 * of the tcpcb each time to conserve mbufs. 1635 */ 1636 void 1637 tcpip_fillheaders(struct inpcb *inp, uint16_t port, void *ip_ptr, void *tcp_ptr) 1638 { 1639 struct tcphdr *th = (struct tcphdr *)tcp_ptr; 1640 1641 INP_WLOCK_ASSERT(inp); 1642 1643 #ifdef INET6 1644 if ((inp->inp_vflag & INP_IPV6) != 0) { 1645 struct ip6_hdr *ip6; 1646 1647 ip6 = (struct ip6_hdr *)ip_ptr; 1648 ip6->ip6_flow = (ip6->ip6_flow & ~IPV6_FLOWINFO_MASK) | 1649 (inp->inp_flow & IPV6_FLOWINFO_MASK); 1650 ip6->ip6_vfc = (ip6->ip6_vfc & ~IPV6_VERSION_MASK) | 1651 (IPV6_VERSION & IPV6_VERSION_MASK); 1652 if (port == 0) 1653 ip6->ip6_nxt = IPPROTO_TCP; 1654 else 1655 ip6->ip6_nxt = IPPROTO_UDP; 1656 ip6->ip6_plen = htons(sizeof(struct tcphdr)); 1657 ip6->ip6_src = inp->in6p_laddr; 1658 ip6->ip6_dst = inp->in6p_faddr; 1659 } 1660 #endif /* INET6 */ 1661 #if defined(INET6) && defined(INET) 1662 else 1663 #endif 1664 #ifdef INET 1665 { 1666 struct ip *ip; 1667 1668 ip = (struct ip *)ip_ptr; 1669 ip->ip_v = IPVERSION; 1670 ip->ip_hl = 5; 1671 ip->ip_tos = inp->inp_ip_tos; 1672 ip->ip_len = 0; 1673 ip->ip_id = 0; 1674 ip->ip_off = 0; 1675 ip->ip_ttl = inp->inp_ip_ttl; 1676 ip->ip_sum = 0; 1677 if (port == 0) 1678 ip->ip_p = IPPROTO_TCP; 1679 else 1680 ip->ip_p = IPPROTO_UDP; 1681 ip->ip_src = inp->inp_laddr; 1682 ip->ip_dst = inp->inp_faddr; 1683 } 1684 #endif /* INET */ 1685 th->th_sport = inp->inp_lport; 1686 th->th_dport = inp->inp_fport; 1687 th->th_seq = 0; 1688 th->th_ack = 0; 1689 th->th_x2 = 0; 1690 th->th_off = 5; 1691 th->th_flags = 0; 1692 th->th_win = 0; 1693 th->th_urp = 0; 1694 th->th_sum = 0; /* in_pseudo() is called later for ipv4 */ 1695 } 1696 1697 /* 1698 * Create template to be used to send tcp packets on a connection. 1699 * Allocates an mbuf and fills in a skeletal tcp/ip header. The only 1700 * use for this function is in keepalives, which use tcp_respond. 1701 */ 1702 struct tcptemp * 1703 tcpip_maketemplate(struct inpcb *inp) 1704 { 1705 struct tcptemp *t; 1706 1707 t = malloc(sizeof(*t), M_TEMP, M_NOWAIT); 1708 if (t == NULL) 1709 return (NULL); 1710 tcpip_fillheaders(inp, 0, (void *)&t->tt_ipgen, (void *)&t->tt_t); 1711 return (t); 1712 } 1713 1714 /* 1715 * Send a single message to the TCP at address specified by 1716 * the given TCP/IP header. If m == NULL, then we make a copy 1717 * of the tcpiphdr at th and send directly to the addressed host. 1718 * This is used to force keep alive messages out using the TCP 1719 * template for a connection. If flags are given then we send 1720 * a message back to the TCP which originated the segment th, 1721 * and discard the mbuf containing it and any other attached mbufs. 1722 * 1723 * In any case the ack and sequence number of the transmitted 1724 * segment are as specified by the parameters. 1725 * 1726 * NOTE: If m != NULL, then th must point to *inside* the mbuf. 1727 */ 1728 void 1729 tcp_respond(struct tcpcb *tp, void *ipgen, struct tcphdr *th, struct mbuf *m, 1730 tcp_seq ack, tcp_seq seq, int flags) 1731 { 1732 struct tcpopt to; 1733 struct inpcb *inp; 1734 struct ip *ip; 1735 struct mbuf *optm; 1736 struct udphdr *uh = NULL; 1737 struct tcphdr *nth; 1738 struct tcp_log_buffer *lgb; 1739 u_char *optp; 1740 #ifdef INET6 1741 struct ip6_hdr *ip6; 1742 int isipv6; 1743 #endif /* INET6 */ 1744 int optlen, tlen, win, ulen; 1745 bool incl_opts; 1746 uint16_t port; 1747 int output_ret; 1748 #ifdef INVARIANTS 1749 int thflags = th->th_flags; 1750 #endif 1751 1752 KASSERT(tp != NULL || m != NULL, ("tcp_respond: tp and m both NULL")); 1753 NET_EPOCH_ASSERT(); 1754 1755 #ifdef INET6 1756 isipv6 = ((struct ip *)ipgen)->ip_v == (IPV6_VERSION >> 4); 1757 ip6 = ipgen; 1758 #endif /* INET6 */ 1759 ip = ipgen; 1760 1761 if (tp != NULL) { 1762 inp = tp->t_inpcb; 1763 KASSERT(inp != NULL, ("tcp control block w/o inpcb")); 1764 INP_LOCK_ASSERT(inp); 1765 } else 1766 inp = NULL; 1767 1768 if (m != NULL) { 1769 #ifdef INET6 1770 if (isipv6 && ip6 && (ip6->ip6_nxt == IPPROTO_UDP)) 1771 port = m->m_pkthdr.tcp_tun_port; 1772 else 1773 #endif 1774 if (ip && (ip->ip_p == IPPROTO_UDP)) 1775 port = m->m_pkthdr.tcp_tun_port; 1776 else 1777 port = 0; 1778 } else 1779 port = tp->t_port; 1780 1781 incl_opts = false; 1782 win = 0; 1783 if (tp != NULL) { 1784 if (!(flags & TH_RST)) { 1785 win = sbspace(&inp->inp_socket->so_rcv); 1786 if (win > TCP_MAXWIN << tp->rcv_scale) 1787 win = TCP_MAXWIN << tp->rcv_scale; 1788 } 1789 if ((tp->t_flags & TF_NOOPT) == 0) 1790 incl_opts = true; 1791 } 1792 if (m == NULL) { 1793 m = m_gethdr(M_NOWAIT, MT_DATA); 1794 if (m == NULL) 1795 return; 1796 m->m_data += max_linkhdr; 1797 #ifdef INET6 1798 if (isipv6) { 1799 bcopy((caddr_t)ip6, mtod(m, caddr_t), 1800 sizeof(struct ip6_hdr)); 1801 ip6 = mtod(m, struct ip6_hdr *); 1802 nth = (struct tcphdr *)(ip6 + 1); 1803 if (port) { 1804 /* Insert a UDP header */ 1805 uh = (struct udphdr *)nth; 1806 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1807 uh->uh_dport = port; 1808 nth = (struct tcphdr *)(uh + 1); 1809 } 1810 } else 1811 #endif /* INET6 */ 1812 { 1813 bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip)); 1814 ip = mtod(m, struct ip *); 1815 nth = (struct tcphdr *)(ip + 1); 1816 if (port) { 1817 /* Insert a UDP header */ 1818 uh = (struct udphdr *)nth; 1819 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1820 uh->uh_dport = port; 1821 nth = (struct tcphdr *)(uh + 1); 1822 } 1823 } 1824 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr)); 1825 flags = TH_ACK; 1826 } else if ((!M_WRITABLE(m)) || (port != 0)) { 1827 struct mbuf *n; 1828 1829 /* Can't reuse 'm', allocate a new mbuf. */ 1830 n = m_gethdr(M_NOWAIT, MT_DATA); 1831 if (n == NULL) { 1832 m_freem(m); 1833 return; 1834 } 1835 1836 if (!m_dup_pkthdr(n, m, M_NOWAIT)) { 1837 m_freem(m); 1838 m_freem(n); 1839 return; 1840 } 1841 1842 n->m_data += max_linkhdr; 1843 /* m_len is set later */ 1844 #define xchg(a,b,type) { type t; t=a; a=b; b=t; } 1845 #ifdef INET6 1846 if (isipv6) { 1847 bcopy((caddr_t)ip6, mtod(n, caddr_t), 1848 sizeof(struct ip6_hdr)); 1849 ip6 = mtod(n, struct ip6_hdr *); 1850 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); 1851 nth = (struct tcphdr *)(ip6 + 1); 1852 if (port) { 1853 /* Insert a UDP header */ 1854 uh = (struct udphdr *)nth; 1855 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1856 uh->uh_dport = port; 1857 nth = (struct tcphdr *)(uh + 1); 1858 } 1859 } else 1860 #endif /* INET6 */ 1861 { 1862 bcopy((caddr_t)ip, mtod(n, caddr_t), sizeof(struct ip)); 1863 ip = mtod(n, struct ip *); 1864 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t); 1865 nth = (struct tcphdr *)(ip + 1); 1866 if (port) { 1867 /* Insert a UDP header */ 1868 uh = (struct udphdr *)nth; 1869 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1870 uh->uh_dport = port; 1871 nth = (struct tcphdr *)(uh + 1); 1872 } 1873 } 1874 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr)); 1875 xchg(nth->th_dport, nth->th_sport, uint16_t); 1876 th = nth; 1877 m_freem(m); 1878 m = n; 1879 } else { 1880 /* 1881 * reuse the mbuf. 1882 * XXX MRT We inherit the FIB, which is lucky. 1883 */ 1884 m_freem(m->m_next); 1885 m->m_next = NULL; 1886 m->m_data = (caddr_t)ipgen; 1887 /* m_len is set later */ 1888 #ifdef INET6 1889 if (isipv6) { 1890 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); 1891 nth = (struct tcphdr *)(ip6 + 1); 1892 } else 1893 #endif /* INET6 */ 1894 { 1895 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t); 1896 nth = (struct tcphdr *)(ip + 1); 1897 } 1898 if (th != nth) { 1899 /* 1900 * this is usually a case when an extension header 1901 * exists between the IPv6 header and the 1902 * TCP header. 1903 */ 1904 nth->th_sport = th->th_sport; 1905 nth->th_dport = th->th_dport; 1906 } 1907 xchg(nth->th_dport, nth->th_sport, uint16_t); 1908 #undef xchg 1909 } 1910 tlen = 0; 1911 #ifdef INET6 1912 if (isipv6) 1913 tlen = sizeof (struct ip6_hdr) + sizeof (struct tcphdr); 1914 #endif 1915 #if defined(INET) && defined(INET6) 1916 else 1917 #endif 1918 #ifdef INET 1919 tlen = sizeof (struct tcpiphdr); 1920 #endif 1921 if (port) 1922 tlen += sizeof (struct udphdr); 1923 #ifdef INVARIANTS 1924 m->m_len = 0; 1925 KASSERT(M_TRAILINGSPACE(m) >= tlen, 1926 ("Not enough trailing space for message (m=%p, need=%d, have=%ld)", 1927 m, tlen, (long)M_TRAILINGSPACE(m))); 1928 #endif 1929 m->m_len = tlen; 1930 to.to_flags = 0; 1931 if (incl_opts) { 1932 /* Make sure we have room. */ 1933 if (M_TRAILINGSPACE(m) < TCP_MAXOLEN) { 1934 m->m_next = m_get(M_NOWAIT, MT_DATA); 1935 if (m->m_next) { 1936 optp = mtod(m->m_next, u_char *); 1937 optm = m->m_next; 1938 } else 1939 incl_opts = false; 1940 } else { 1941 optp = (u_char *) (nth + 1); 1942 optm = m; 1943 } 1944 } 1945 if (incl_opts) { 1946 /* Timestamps. */ 1947 if (tp->t_flags & TF_RCVD_TSTMP) { 1948 to.to_tsval = tcp_ts_getticks() + tp->ts_offset; 1949 to.to_tsecr = tp->ts_recent; 1950 to.to_flags |= TOF_TS; 1951 } 1952 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 1953 /* TCP-MD5 (RFC2385). */ 1954 if (tp->t_flags & TF_SIGNATURE) 1955 to.to_flags |= TOF_SIGNATURE; 1956 #endif 1957 /* Add the options. */ 1958 tlen += optlen = tcp_addoptions(&to, optp); 1959 1960 /* Update m_len in the correct mbuf. */ 1961 optm->m_len += optlen; 1962 } else 1963 optlen = 0; 1964 #ifdef INET6 1965 if (isipv6) { 1966 if (uh) { 1967 ulen = tlen - sizeof(struct ip6_hdr); 1968 uh->uh_ulen = htons(ulen); 1969 } 1970 ip6->ip6_flow = 0; 1971 ip6->ip6_vfc = IPV6_VERSION; 1972 if (port) 1973 ip6->ip6_nxt = IPPROTO_UDP; 1974 else 1975 ip6->ip6_nxt = IPPROTO_TCP; 1976 ip6->ip6_plen = htons(tlen - sizeof(*ip6)); 1977 } 1978 #endif 1979 #if defined(INET) && defined(INET6) 1980 else 1981 #endif 1982 #ifdef INET 1983 { 1984 if (uh) { 1985 ulen = tlen - sizeof(struct ip); 1986 uh->uh_ulen = htons(ulen); 1987 } 1988 ip->ip_len = htons(tlen); 1989 ip->ip_ttl = V_ip_defttl; 1990 if (port) { 1991 ip->ip_p = IPPROTO_UDP; 1992 } else { 1993 ip->ip_p = IPPROTO_TCP; 1994 } 1995 if (V_path_mtu_discovery) 1996 ip->ip_off |= htons(IP_DF); 1997 } 1998 #endif 1999 m->m_pkthdr.len = tlen; 2000 m->m_pkthdr.rcvif = NULL; 2001 #ifdef MAC 2002 if (inp != NULL) { 2003 /* 2004 * Packet is associated with a socket, so allow the 2005 * label of the response to reflect the socket label. 2006 */ 2007 INP_LOCK_ASSERT(inp); 2008 mac_inpcb_create_mbuf(inp, m); 2009 } else { 2010 /* 2011 * Packet is not associated with a socket, so possibly 2012 * update the label in place. 2013 */ 2014 mac_netinet_tcp_reply(m); 2015 } 2016 #endif 2017 nth->th_seq = htonl(seq); 2018 nth->th_ack = htonl(ack); 2019 nth->th_x2 = 0; 2020 nth->th_off = (sizeof (struct tcphdr) + optlen) >> 2; 2021 nth->th_flags = flags; 2022 if (tp != NULL) 2023 nth->th_win = htons((u_short) (win >> tp->rcv_scale)); 2024 else 2025 nth->th_win = htons((u_short)win); 2026 nth->th_urp = 0; 2027 2028 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 2029 if (to.to_flags & TOF_SIGNATURE) { 2030 if (!TCPMD5_ENABLED() || 2031 TCPMD5_OUTPUT(m, nth, to.to_signature) != 0) { 2032 m_freem(m); 2033 return; 2034 } 2035 } 2036 #endif 2037 2038 #ifdef INET6 2039 if (isipv6) { 2040 if (port) { 2041 m->m_pkthdr.csum_flags = CSUM_UDP_IPV6; 2042 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 2043 uh->uh_sum = in6_cksum_pseudo(ip6, ulen, IPPROTO_UDP, 0); 2044 nth->th_sum = 0; 2045 } else { 2046 m->m_pkthdr.csum_flags = CSUM_TCP_IPV6; 2047 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); 2048 nth->th_sum = in6_cksum_pseudo(ip6, 2049 tlen - sizeof(struct ip6_hdr), IPPROTO_TCP, 0); 2050 } 2051 ip6->ip6_hlim = in6_selecthlim(tp != NULL ? tp->t_inpcb : 2052 NULL, NULL); 2053 } 2054 #endif /* INET6 */ 2055 #if defined(INET6) && defined(INET) 2056 else 2057 #endif 2058 #ifdef INET 2059 { 2060 if (port) { 2061 uh->uh_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, 2062 htons(ulen + IPPROTO_UDP)); 2063 m->m_pkthdr.csum_flags = CSUM_UDP; 2064 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 2065 nth->th_sum = 0; 2066 } else { 2067 m->m_pkthdr.csum_flags = CSUM_TCP; 2068 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); 2069 nth->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, 2070 htons((u_short)(tlen - sizeof(struct ip) + ip->ip_p))); 2071 } 2072 } 2073 #endif /* INET */ 2074 #ifdef TCPDEBUG 2075 if (tp == NULL || (inp->inp_socket->so_options & SO_DEBUG)) 2076 tcp_trace(TA_OUTPUT, 0, tp, mtod(m, void *), th, 0); 2077 #endif 2078 TCP_PROBE3(debug__output, tp, th, m); 2079 if (flags & TH_RST) 2080 TCP_PROBE5(accept__refused, NULL, NULL, m, tp, nth); 2081 lgb = NULL; 2082 if ((tp != NULL) && (tp->t_logstate != TCP_LOG_STATE_OFF)) { 2083 if (INP_WLOCKED(inp)) { 2084 union tcp_log_stackspecific log; 2085 struct timeval tv; 2086 2087 memset(&log.u_bbr, 0, sizeof(log.u_bbr)); 2088 log.u_bbr.inhpts = tp->t_inpcb->inp_in_hpts; 2089 log.u_bbr.flex8 = 4; 2090 log.u_bbr.pkts_out = tp->t_maxseg; 2091 log.u_bbr.timeStamp = tcp_get_usecs(&tv); 2092 log.u_bbr.delivered = 0; 2093 lgb = tcp_log_event_(tp, nth, NULL, NULL, TCP_LOG_OUT, 2094 ERRNO_UNK, 0, &log, false, NULL, NULL, 0, &tv); 2095 } else { 2096 /* 2097 * We can not log the packet, since we only own the 2098 * read lock, but a write lock is needed. The read lock 2099 * is not upgraded to a write lock, since only getting 2100 * the read lock was done intentionally to improve the 2101 * handling of SYN flooding attacks. 2102 * This happens only for pure SYN segments received in 2103 * the initial CLOSED state, or received in a more 2104 * advanced state than listen and the UDP encapsulation 2105 * port is unexpected. 2106 * The incoming SYN segments do not really belong to 2107 * the TCP connection and the handling does not change 2108 * the state of the TCP connection. Therefore, the 2109 * sending of the RST segments is not logged. Please 2110 * note that also the incoming SYN segments are not 2111 * logged. 2112 * 2113 * The following code ensures that the above description 2114 * is and stays correct. 2115 */ 2116 KASSERT((thflags & (TH_ACK|TH_SYN)) == TH_SYN && 2117 (tp->t_state == TCPS_CLOSED || 2118 (tp->t_state > TCPS_LISTEN && tp->t_port != port)), 2119 ("%s: Logging of TCP segment with flags 0x%b and " 2120 "UDP encapsulation port %u skipped in state %s", 2121 __func__, thflags, PRINT_TH_FLAGS, 2122 ntohs(port), tcpstates[tp->t_state])); 2123 } 2124 } 2125 2126 #ifdef INET6 2127 if (isipv6) { 2128 TCP_PROBE5(send, NULL, tp, ip6, tp, nth); 2129 output_ret = ip6_output(m, NULL, NULL, 0, NULL, NULL, inp); 2130 } 2131 #endif /* INET6 */ 2132 #if defined(INET) && defined(INET6) 2133 else 2134 #endif 2135 #ifdef INET 2136 { 2137 TCP_PROBE5(send, NULL, tp, ip, tp, nth); 2138 output_ret = ip_output(m, NULL, NULL, 0, NULL, inp); 2139 } 2140 #endif 2141 if (lgb != NULL) 2142 lgb->tlb_errno = output_ret; 2143 } 2144 2145 /* 2146 * Create a new TCP control block, making an 2147 * empty reassembly queue and hooking it to the argument 2148 * protocol control block. The `inp' parameter must have 2149 * come from the zone allocator set up in tcp_init(). 2150 */ 2151 struct tcpcb * 2152 tcp_newtcpcb(struct inpcb *inp) 2153 { 2154 struct tcpcb_mem *tm; 2155 struct tcpcb *tp; 2156 #ifdef INET6 2157 int isipv6 = (inp->inp_vflag & INP_IPV6) != 0; 2158 #endif /* INET6 */ 2159 2160 tm = uma_zalloc(V_tcpcb_zone, M_NOWAIT | M_ZERO); 2161 if (tm == NULL) 2162 return (NULL); 2163 tp = &tm->tcb; 2164 2165 /* Initialise cc_var struct for this tcpcb. */ 2166 tp->ccv = &tm->ccv; 2167 tp->ccv->type = IPPROTO_TCP; 2168 tp->ccv->ccvc.tcp = tp; 2169 rw_rlock(&tcp_function_lock); 2170 tp->t_fb = tcp_func_set_ptr; 2171 refcount_acquire(&tp->t_fb->tfb_refcnt); 2172 rw_runlock(&tcp_function_lock); 2173 /* 2174 * Use the current system default CC algorithm. 2175 */ 2176 CC_LIST_RLOCK(); 2177 KASSERT(!STAILQ_EMPTY(&cc_list), ("cc_list is empty!")); 2178 CC_ALGO(tp) = CC_DEFAULT_ALGO(); 2179 CC_LIST_RUNLOCK(); 2180 2181 /* 2182 * The tcpcb will hold a reference on its inpcb until tcp_discardcb() 2183 * is called. 2184 */ 2185 in_pcbref(inp); /* Reference for tcpcb */ 2186 tp->t_inpcb = inp; 2187 2188 if (CC_ALGO(tp)->cb_init != NULL) 2189 if (CC_ALGO(tp)->cb_init(tp->ccv, NULL) > 0) { 2190 if (tp->t_fb->tfb_tcp_fb_fini) 2191 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); 2192 in_pcbrele_wlocked(inp); 2193 refcount_release(&tp->t_fb->tfb_refcnt); 2194 uma_zfree(V_tcpcb_zone, tm); 2195 return (NULL); 2196 } 2197 2198 #ifdef TCP_HHOOK 2199 tp->osd = &tm->osd; 2200 if (khelp_init_osd(HELPER_CLASS_TCP, tp->osd)) { 2201 if (tp->t_fb->tfb_tcp_fb_fini) 2202 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); 2203 in_pcbrele_wlocked(inp); 2204 refcount_release(&tp->t_fb->tfb_refcnt); 2205 uma_zfree(V_tcpcb_zone, tm); 2206 return (NULL); 2207 } 2208 #endif 2209 2210 #ifdef VIMAGE 2211 tp->t_vnet = inp->inp_vnet; 2212 #endif 2213 tp->t_timers = &tm->tt; 2214 TAILQ_INIT(&tp->t_segq); 2215 tp->t_maxseg = 2216 #ifdef INET6 2217 isipv6 ? V_tcp_v6mssdflt : 2218 #endif /* INET6 */ 2219 V_tcp_mssdflt; 2220 2221 /* Set up our timeouts. */ 2222 callout_init(&tp->t_timers->tt_rexmt, 1); 2223 callout_init(&tp->t_timers->tt_persist, 1); 2224 callout_init(&tp->t_timers->tt_keep, 1); 2225 callout_init(&tp->t_timers->tt_2msl, 1); 2226 callout_init(&tp->t_timers->tt_delack, 1); 2227 2228 if (V_tcp_do_rfc1323) 2229 tp->t_flags = (TF_REQ_SCALE|TF_REQ_TSTMP); 2230 if (V_tcp_do_sack) 2231 tp->t_flags |= TF_SACK_PERMIT; 2232 TAILQ_INIT(&tp->snd_holes); 2233 2234 /* 2235 * Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no 2236 * rtt estimate. Set rttvar so that srtt + 4 * rttvar gives 2237 * reasonable initial retransmit time. 2238 */ 2239 tp->t_srtt = TCPTV_SRTTBASE; 2240 tp->t_rttvar = ((tcp_rexmit_initial - TCPTV_SRTTBASE) << TCP_RTTVAR_SHIFT) / 4; 2241 tp->t_rttmin = tcp_rexmit_min; 2242 tp->t_rxtcur = tcp_rexmit_initial; 2243 tp->snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT; 2244 tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT; 2245 tp->t_rcvtime = ticks; 2246 /* 2247 * IPv4 TTL initialization is necessary for an IPv6 socket as well, 2248 * because the socket may be bound to an IPv6 wildcard address, 2249 * which may match an IPv4-mapped IPv6 address. 2250 */ 2251 inp->inp_ip_ttl = V_ip_defttl; 2252 inp->inp_ppcb = tp; 2253 #ifdef TCPPCAP 2254 /* 2255 * Init the TCP PCAP queues. 2256 */ 2257 tcp_pcap_tcpcb_init(tp); 2258 #endif 2259 #ifdef TCP_BLACKBOX 2260 /* Initialize the per-TCPCB log data. */ 2261 tcp_log_tcpcbinit(tp); 2262 #endif 2263 tp->t_pacing_rate = -1; 2264 if (tp->t_fb->tfb_tcp_fb_init) { 2265 if ((*tp->t_fb->tfb_tcp_fb_init)(tp)) { 2266 refcount_release(&tp->t_fb->tfb_refcnt); 2267 in_pcbrele_wlocked(inp); 2268 uma_zfree(V_tcpcb_zone, tm); 2269 return (NULL); 2270 } 2271 } 2272 #ifdef STATS 2273 if (V_tcp_perconn_stats_enable == 1) 2274 tp->t_stats = stats_blob_alloc(V_tcp_perconn_stats_dflt_tpl, 0); 2275 #endif 2276 if (V_tcp_do_lrd) 2277 tp->t_flags |= TF_LRD; 2278 return (tp); /* XXX */ 2279 } 2280 2281 /* 2282 * Switch the congestion control algorithm back to Vnet default for any active 2283 * control blocks using an algorithm which is about to go away. If the algorithm 2284 * has a cb_init function and it fails (no memory) then the operation fails and 2285 * the unload will not succeed. 2286 * 2287 */ 2288 int 2289 tcp_ccalgounload(struct cc_algo *unload_algo) 2290 { 2291 struct cc_algo *oldalgo, *newalgo; 2292 struct inpcb *inp; 2293 struct tcpcb *tp; 2294 VNET_ITERATOR_DECL(vnet_iter); 2295 2296 /* 2297 * Check all active control blocks across all network stacks and change 2298 * any that are using "unload_algo" back to its default. If "unload_algo" 2299 * requires cleanup code to be run, call it. 2300 */ 2301 VNET_LIST_RLOCK(); 2302 VNET_FOREACH(vnet_iter) { 2303 CURVNET_SET(vnet_iter); 2304 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, 2305 INPLOOKUP_WLOCKPCB); 2306 /* 2307 * XXXGL: would new accept(2)d connections use algo being 2308 * unloaded? 2309 */ 2310 newalgo = CC_DEFAULT_ALGO(); 2311 while ((inp = inp_next(&inpi)) != NULL) { 2312 /* Important to skip tcptw structs. */ 2313 if (!(inp->inp_flags & INP_TIMEWAIT) && 2314 (tp = intotcpcb(inp)) != NULL) { 2315 /* 2316 * By holding INP_WLOCK here, we are assured 2317 * that the connection is not currently 2318 * executing inside the CC module's functions. 2319 * We attempt to switch to the Vnets default, 2320 * if the init fails then we fail the whole 2321 * operation and the module unload will fail. 2322 */ 2323 if (CC_ALGO(tp) == unload_algo) { 2324 struct cc_var cc_mem; 2325 int err; 2326 2327 oldalgo = CC_ALGO(tp); 2328 memset(&cc_mem, 0, sizeof(cc_mem)); 2329 cc_mem.ccvc.tcp = tp; 2330 if (newalgo->cb_init == NULL) { 2331 /* 2332 * No init we can skip the 2333 * dance around a possible failure. 2334 */ 2335 CC_DATA(tp) = NULL; 2336 goto proceed; 2337 } 2338 err = (newalgo->cb_init)(&cc_mem, NULL); 2339 if (err) { 2340 /* 2341 * Presumably no memory the caller will 2342 * need to try again. 2343 */ 2344 INP_WUNLOCK(inp); 2345 CURVNET_RESTORE(); 2346 VNET_LIST_RUNLOCK(); 2347 return (err); 2348 } 2349 proceed: 2350 if (oldalgo->cb_destroy != NULL) 2351 oldalgo->cb_destroy(tp->ccv); 2352 CC_ALGO(tp) = newalgo; 2353 memcpy(tp->ccv, &cc_mem, sizeof(struct cc_var)); 2354 if (TCPS_HAVEESTABLISHED(tp->t_state) && 2355 (CC_ALGO(tp)->conn_init != NULL)) { 2356 /* Yep run the connection init for the new CC */ 2357 CC_ALGO(tp)->conn_init(tp->ccv); 2358 } 2359 } 2360 } 2361 } 2362 CURVNET_RESTORE(); 2363 } 2364 VNET_LIST_RUNLOCK(); 2365 return (0); 2366 } 2367 2368 /* 2369 * Drop a TCP connection, reporting 2370 * the specified error. If connection is synchronized, 2371 * then send a RST to peer. 2372 */ 2373 struct tcpcb * 2374 tcp_drop(struct tcpcb *tp, int errno) 2375 { 2376 struct socket *so = tp->t_inpcb->inp_socket; 2377 2378 NET_EPOCH_ASSERT(); 2379 INP_WLOCK_ASSERT(tp->t_inpcb); 2380 2381 if (TCPS_HAVERCVDSYN(tp->t_state)) { 2382 tcp_state_change(tp, TCPS_CLOSED); 2383 /* Don't use tcp_output() here due to possible recursion. */ 2384 (void)tcp_output_nodrop(tp); 2385 TCPSTAT_INC(tcps_drops); 2386 } else 2387 TCPSTAT_INC(tcps_conndrops); 2388 if (errno == ETIMEDOUT && tp->t_softerror) 2389 errno = tp->t_softerror; 2390 so->so_error = errno; 2391 return (tcp_close(tp)); 2392 } 2393 2394 void 2395 tcp_discardcb(struct tcpcb *tp) 2396 { 2397 struct inpcb *inp = tp->t_inpcb; 2398 2399 INP_WLOCK_ASSERT(inp); 2400 2401 /* 2402 * Make sure that all of our timers are stopped before we delete the 2403 * PCB. 2404 * 2405 * If stopping a timer fails, we schedule a discard function in same 2406 * callout, and the last discard function called will take care of 2407 * deleting the tcpcb. 2408 */ 2409 tp->t_timers->tt_draincnt = 0; 2410 tcp_timer_stop(tp, TT_REXMT); 2411 tcp_timer_stop(tp, TT_PERSIST); 2412 tcp_timer_stop(tp, TT_KEEP); 2413 tcp_timer_stop(tp, TT_2MSL); 2414 tcp_timer_stop(tp, TT_DELACK); 2415 if (tp->t_fb->tfb_tcp_timer_stop_all) { 2416 /* 2417 * Call the stop-all function of the methods, 2418 * this function should call the tcp_timer_stop() 2419 * method with each of the function specific timeouts. 2420 * That stop will be called via the tfb_tcp_timer_stop() 2421 * which should use the async drain function of the 2422 * callout system (see tcp_var.h). 2423 */ 2424 tp->t_fb->tfb_tcp_timer_stop_all(tp); 2425 } 2426 2427 /* free the reassembly queue, if any */ 2428 tcp_reass_flush(tp); 2429 2430 #ifdef TCP_OFFLOAD 2431 /* Disconnect offload device, if any. */ 2432 if (tp->t_flags & TF_TOE) 2433 tcp_offload_detach(tp); 2434 #endif 2435 2436 tcp_free_sackholes(tp); 2437 2438 #ifdef TCPPCAP 2439 /* Free the TCP PCAP queues. */ 2440 tcp_pcap_drain(&(tp->t_inpkts)); 2441 tcp_pcap_drain(&(tp->t_outpkts)); 2442 #endif 2443 2444 /* Allow the CC algorithm to clean up after itself. */ 2445 if (CC_ALGO(tp)->cb_destroy != NULL) 2446 CC_ALGO(tp)->cb_destroy(tp->ccv); 2447 CC_DATA(tp) = NULL; 2448 2449 #ifdef TCP_HHOOK 2450 khelp_destroy_osd(tp->osd); 2451 #endif 2452 #ifdef STATS 2453 stats_blob_destroy(tp->t_stats); 2454 #endif 2455 2456 CC_ALGO(tp) = NULL; 2457 inp->inp_ppcb = NULL; 2458 if (tp->t_timers->tt_draincnt == 0) { 2459 bool released __diagused; 2460 2461 released = tcp_freecb(tp); 2462 KASSERT(!released, ("%s: inp %p should not have been released " 2463 "here", __func__, inp)); 2464 } 2465 } 2466 2467 bool 2468 tcp_freecb(struct tcpcb *tp) 2469 { 2470 struct inpcb *inp = tp->t_inpcb; 2471 struct socket *so = inp->inp_socket; 2472 #ifdef INET6 2473 bool isipv6 = (inp->inp_vflag & INP_IPV6) != 0; 2474 #endif 2475 2476 INP_WLOCK_ASSERT(inp); 2477 MPASS(tp->t_timers->tt_draincnt == 0); 2478 2479 /* We own the last reference on tcpcb, let's free it. */ 2480 #ifdef TCP_BLACKBOX 2481 tcp_log_tcpcbfini(tp); 2482 #endif 2483 TCPSTATES_DEC(tp->t_state); 2484 if (tp->t_fb->tfb_tcp_fb_fini) 2485 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); 2486 2487 /* 2488 * If we got enough samples through the srtt filter, 2489 * save the rtt and rttvar in the routing entry. 2490 * 'Enough' is arbitrarily defined as 4 rtt samples. 2491 * 4 samples is enough for the srtt filter to converge 2492 * to within enough % of the correct value; fewer samples 2493 * and we could save a bogus rtt. The danger is not high 2494 * as tcp quickly recovers from everything. 2495 * XXX: Works very well but needs some more statistics! 2496 * 2497 * XXXRRS: Updating must be after the stack fini() since 2498 * that may be converting some internal representation of 2499 * say srtt etc into the general one used by other stacks. 2500 * Lets also at least protect against the so being NULL 2501 * as RW stated below. 2502 */ 2503 if ((tp->t_rttupdated >= 4) && (so != NULL)) { 2504 struct hc_metrics_lite metrics; 2505 uint32_t ssthresh; 2506 2507 bzero(&metrics, sizeof(metrics)); 2508 /* 2509 * Update the ssthresh always when the conditions below 2510 * are satisfied. This gives us better new start value 2511 * for the congestion avoidance for new connections. 2512 * ssthresh is only set if packet loss occurred on a session. 2513 * 2514 * XXXRW: 'so' may be NULL here, and/or socket buffer may be 2515 * being torn down. Ideally this code would not use 'so'. 2516 */ 2517 ssthresh = tp->snd_ssthresh; 2518 if (ssthresh != 0 && ssthresh < so->so_snd.sb_hiwat / 2) { 2519 /* 2520 * convert the limit from user data bytes to 2521 * packets then to packet data bytes. 2522 */ 2523 ssthresh = (ssthresh + tp->t_maxseg / 2) / tp->t_maxseg; 2524 if (ssthresh < 2) 2525 ssthresh = 2; 2526 ssthresh *= (tp->t_maxseg + 2527 #ifdef INET6 2528 (isipv6 ? sizeof (struct ip6_hdr) + 2529 sizeof (struct tcphdr) : 2530 #endif 2531 sizeof (struct tcpiphdr) 2532 #ifdef INET6 2533 ) 2534 #endif 2535 ); 2536 } else 2537 ssthresh = 0; 2538 metrics.rmx_ssthresh = ssthresh; 2539 2540 metrics.rmx_rtt = tp->t_srtt; 2541 metrics.rmx_rttvar = tp->t_rttvar; 2542 metrics.rmx_cwnd = tp->snd_cwnd; 2543 metrics.rmx_sendpipe = 0; 2544 metrics.rmx_recvpipe = 0; 2545 2546 tcp_hc_update(&inp->inp_inc, &metrics); 2547 } 2548 2549 refcount_release(&tp->t_fb->tfb_refcnt); 2550 uma_zfree(V_tcpcb_zone, tp); 2551 2552 return (in_pcbrele_wlocked(inp)); 2553 } 2554 2555 /* 2556 * Attempt to close a TCP control block, marking it as dropped, and freeing 2557 * the socket if we hold the only reference. 2558 */ 2559 struct tcpcb * 2560 tcp_close(struct tcpcb *tp) 2561 { 2562 struct inpcb *inp = tp->t_inpcb; 2563 struct socket *so; 2564 2565 INP_WLOCK_ASSERT(inp); 2566 2567 #ifdef TCP_OFFLOAD 2568 if (tp->t_state == TCPS_LISTEN) 2569 tcp_offload_listen_stop(tp); 2570 #endif 2571 /* 2572 * This releases the TFO pending counter resource for TFO listen 2573 * sockets as well as passively-created TFO sockets that transition 2574 * from SYN_RECEIVED to CLOSED. 2575 */ 2576 if (tp->t_tfo_pending) { 2577 tcp_fastopen_decrement_counter(tp->t_tfo_pending); 2578 tp->t_tfo_pending = NULL; 2579 } 2580 #ifdef TCPHPTS 2581 tcp_hpts_remove(inp); 2582 #endif 2583 in_pcbdrop(inp); 2584 TCPSTAT_INC(tcps_closed); 2585 if (tp->t_state != TCPS_CLOSED) 2586 tcp_state_change(tp, TCPS_CLOSED); 2587 KASSERT(inp->inp_socket != NULL, ("tcp_close: inp_socket NULL")); 2588 so = inp->inp_socket; 2589 soisdisconnected(so); 2590 if (inp->inp_flags & INP_SOCKREF) { 2591 KASSERT(so->so_state & SS_PROTOREF, 2592 ("tcp_close: !SS_PROTOREF")); 2593 inp->inp_flags &= ~INP_SOCKREF; 2594 INP_WUNLOCK(inp); 2595 SOCK_LOCK(so); 2596 so->so_state &= ~SS_PROTOREF; 2597 sofree(so); 2598 return (NULL); 2599 } 2600 return (tp); 2601 } 2602 2603 void 2604 tcp_drain(void) 2605 { 2606 VNET_ITERATOR_DECL(vnet_iter); 2607 2608 if (!do_tcpdrain) 2609 return; 2610 2611 VNET_LIST_RLOCK_NOSLEEP(); 2612 VNET_FOREACH(vnet_iter) { 2613 CURVNET_SET(vnet_iter); 2614 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, 2615 INPLOOKUP_WLOCKPCB); 2616 struct inpcb *inpb; 2617 struct tcpcb *tcpb; 2618 2619 /* 2620 * Walk the tcpbs, if existing, and flush the reassembly queue, 2621 * if there is one... 2622 * XXX: The "Net/3" implementation doesn't imply that the TCP 2623 * reassembly queue should be flushed, but in a situation 2624 * where we're really low on mbufs, this is potentially 2625 * useful. 2626 */ 2627 while ((inpb = inp_next(&inpi)) != NULL) { 2628 if (inpb->inp_flags & INP_TIMEWAIT) 2629 continue; 2630 if ((tcpb = intotcpcb(inpb)) != NULL) { 2631 tcp_reass_flush(tcpb); 2632 tcp_clean_sackreport(tcpb); 2633 #ifdef TCP_BLACKBOX 2634 tcp_log_drain(tcpb); 2635 #endif 2636 #ifdef TCPPCAP 2637 if (tcp_pcap_aggressive_free) { 2638 /* Free the TCP PCAP queues. */ 2639 tcp_pcap_drain(&(tcpb->t_inpkts)); 2640 tcp_pcap_drain(&(tcpb->t_outpkts)); 2641 } 2642 #endif 2643 } 2644 } 2645 CURVNET_RESTORE(); 2646 } 2647 VNET_LIST_RUNLOCK_NOSLEEP(); 2648 } 2649 2650 /* 2651 * Notify a tcp user of an asynchronous error; 2652 * store error as soft error, but wake up user 2653 * (for now, won't do anything until can select for soft error). 2654 * 2655 * Do not wake up user since there currently is no mechanism for 2656 * reporting soft errors (yet - a kqueue filter may be added). 2657 */ 2658 static struct inpcb * 2659 tcp_notify(struct inpcb *inp, int error) 2660 { 2661 struct tcpcb *tp; 2662 2663 INP_WLOCK_ASSERT(inp); 2664 2665 if ((inp->inp_flags & INP_TIMEWAIT) || 2666 (inp->inp_flags & INP_DROPPED)) 2667 return (inp); 2668 2669 tp = intotcpcb(inp); 2670 KASSERT(tp != NULL, ("tcp_notify: tp == NULL")); 2671 2672 /* 2673 * Ignore some errors if we are hooked up. 2674 * If connection hasn't completed, has retransmitted several times, 2675 * and receives a second error, give up now. This is better 2676 * than waiting a long time to establish a connection that 2677 * can never complete. 2678 */ 2679 if (tp->t_state == TCPS_ESTABLISHED && 2680 (error == EHOSTUNREACH || error == ENETUNREACH || 2681 error == EHOSTDOWN)) { 2682 if (inp->inp_route.ro_nh) { 2683 NH_FREE(inp->inp_route.ro_nh); 2684 inp->inp_route.ro_nh = (struct nhop_object *)NULL; 2685 } 2686 return (inp); 2687 } else if (tp->t_state < TCPS_ESTABLISHED && tp->t_rxtshift > 3 && 2688 tp->t_softerror) { 2689 tp = tcp_drop(tp, error); 2690 if (tp != NULL) 2691 return (inp); 2692 else 2693 return (NULL); 2694 } else { 2695 tp->t_softerror = error; 2696 return (inp); 2697 } 2698 #if 0 2699 wakeup( &so->so_timeo); 2700 sorwakeup(so); 2701 sowwakeup(so); 2702 #endif 2703 } 2704 2705 static int 2706 tcp_pcblist(SYSCTL_HANDLER_ARGS) 2707 { 2708 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, 2709 INPLOOKUP_RLOCKPCB); 2710 struct xinpgen xig; 2711 struct inpcb *inp; 2712 int error; 2713 2714 if (req->newptr != NULL) 2715 return (EPERM); 2716 2717 if (req->oldptr == NULL) { 2718 int n; 2719 2720 n = V_tcbinfo.ipi_count + 2721 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); 2722 n += imax(n / 8, 10); 2723 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xtcpcb); 2724 return (0); 2725 } 2726 2727 if ((error = sysctl_wire_old_buffer(req, 0)) != 0) 2728 return (error); 2729 2730 bzero(&xig, sizeof(xig)); 2731 xig.xig_len = sizeof xig; 2732 xig.xig_count = V_tcbinfo.ipi_count + 2733 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); 2734 xig.xig_gen = V_tcbinfo.ipi_gencnt; 2735 xig.xig_sogen = so_gencnt; 2736 error = SYSCTL_OUT(req, &xig, sizeof xig); 2737 if (error) 2738 return (error); 2739 2740 error = syncache_pcblist(req); 2741 if (error) 2742 return (error); 2743 2744 while ((inp = inp_next(&inpi)) != NULL) { 2745 if (inp->inp_gencnt <= xig.xig_gen) { 2746 int crerr; 2747 2748 /* 2749 * XXX: This use of cr_cansee(), introduced with 2750 * TCP state changes, is not quite right, but for 2751 * now, better than nothing. 2752 */ 2753 if (inp->inp_flags & INP_TIMEWAIT) { 2754 if (intotw(inp) != NULL) 2755 crerr = cr_cansee(req->td->td_ucred, 2756 intotw(inp)->tw_cred); 2757 else 2758 crerr = EINVAL; /* Skip this inp. */ 2759 } else 2760 crerr = cr_canseeinpcb(req->td->td_ucred, inp); 2761 if (crerr == 0) { 2762 struct xtcpcb xt; 2763 2764 tcp_inptoxtp(inp, &xt); 2765 error = SYSCTL_OUT(req, &xt, sizeof xt); 2766 if (error) { 2767 INP_RUNLOCK(inp); 2768 break; 2769 } else 2770 continue; 2771 } 2772 } 2773 } 2774 2775 if (!error) { 2776 /* 2777 * Give the user an updated idea of our state. 2778 * If the generation differs from what we told 2779 * her before, she knows that something happened 2780 * while we were processing this request, and it 2781 * might be necessary to retry. 2782 */ 2783 xig.xig_gen = V_tcbinfo.ipi_gencnt; 2784 xig.xig_sogen = so_gencnt; 2785 xig.xig_count = V_tcbinfo.ipi_count + 2786 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); 2787 error = SYSCTL_OUT(req, &xig, sizeof xig); 2788 } 2789 2790 return (error); 2791 } 2792 2793 SYSCTL_PROC(_net_inet_tcp, TCPCTL_PCBLIST, pcblist, 2794 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_NEEDGIANT, 2795 NULL, 0, tcp_pcblist, "S,xtcpcb", 2796 "List of active TCP connections"); 2797 2798 #ifdef INET 2799 static int 2800 tcp_getcred(SYSCTL_HANDLER_ARGS) 2801 { 2802 struct xucred xuc; 2803 struct sockaddr_in addrs[2]; 2804 struct epoch_tracker et; 2805 struct inpcb *inp; 2806 int error; 2807 2808 error = priv_check(req->td, PRIV_NETINET_GETCRED); 2809 if (error) 2810 return (error); 2811 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 2812 if (error) 2813 return (error); 2814 NET_EPOCH_ENTER(et); 2815 inp = in_pcblookup(&V_tcbinfo, addrs[1].sin_addr, addrs[1].sin_port, 2816 addrs[0].sin_addr, addrs[0].sin_port, INPLOOKUP_RLOCKPCB, NULL); 2817 NET_EPOCH_EXIT(et); 2818 if (inp != NULL) { 2819 if (inp->inp_socket == NULL) 2820 error = ENOENT; 2821 if (error == 0) 2822 error = cr_canseeinpcb(req->td->td_ucred, inp); 2823 if (error == 0) 2824 cru2x(inp->inp_cred, &xuc); 2825 INP_RUNLOCK(inp); 2826 } else 2827 error = ENOENT; 2828 if (error == 0) 2829 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 2830 return (error); 2831 } 2832 2833 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, getcred, 2834 CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_NEEDGIANT, 2835 0, 0, tcp_getcred, "S,xucred", 2836 "Get the xucred of a TCP connection"); 2837 #endif /* INET */ 2838 2839 #ifdef INET6 2840 static int 2841 tcp6_getcred(SYSCTL_HANDLER_ARGS) 2842 { 2843 struct epoch_tracker et; 2844 struct xucred xuc; 2845 struct sockaddr_in6 addrs[2]; 2846 struct inpcb *inp; 2847 int error; 2848 #ifdef INET 2849 int mapped = 0; 2850 #endif 2851 2852 error = priv_check(req->td, PRIV_NETINET_GETCRED); 2853 if (error) 2854 return (error); 2855 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 2856 if (error) 2857 return (error); 2858 if ((error = sa6_embedscope(&addrs[0], V_ip6_use_defzone)) != 0 || 2859 (error = sa6_embedscope(&addrs[1], V_ip6_use_defzone)) != 0) { 2860 return (error); 2861 } 2862 if (IN6_IS_ADDR_V4MAPPED(&addrs[0].sin6_addr)) { 2863 #ifdef INET 2864 if (IN6_IS_ADDR_V4MAPPED(&addrs[1].sin6_addr)) 2865 mapped = 1; 2866 else 2867 #endif 2868 return (EINVAL); 2869 } 2870 2871 NET_EPOCH_ENTER(et); 2872 #ifdef INET 2873 if (mapped == 1) 2874 inp = in_pcblookup(&V_tcbinfo, 2875 *(struct in_addr *)&addrs[1].sin6_addr.s6_addr[12], 2876 addrs[1].sin6_port, 2877 *(struct in_addr *)&addrs[0].sin6_addr.s6_addr[12], 2878 addrs[0].sin6_port, INPLOOKUP_RLOCKPCB, NULL); 2879 else 2880 #endif 2881 inp = in6_pcblookup(&V_tcbinfo, 2882 &addrs[1].sin6_addr, addrs[1].sin6_port, 2883 &addrs[0].sin6_addr, addrs[0].sin6_port, 2884 INPLOOKUP_RLOCKPCB, NULL); 2885 NET_EPOCH_EXIT(et); 2886 if (inp != NULL) { 2887 if (inp->inp_socket == NULL) 2888 error = ENOENT; 2889 if (error == 0) 2890 error = cr_canseeinpcb(req->td->td_ucred, inp); 2891 if (error == 0) 2892 cru2x(inp->inp_cred, &xuc); 2893 INP_RUNLOCK(inp); 2894 } else 2895 error = ENOENT; 2896 if (error == 0) 2897 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 2898 return (error); 2899 } 2900 2901 SYSCTL_PROC(_net_inet6_tcp6, OID_AUTO, getcred, 2902 CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_NEEDGIANT, 2903 0, 0, tcp6_getcred, "S,xucred", 2904 "Get the xucred of a TCP6 connection"); 2905 #endif /* INET6 */ 2906 2907 #ifdef INET 2908 /* Path MTU to try next when a fragmentation-needed message is received. */ 2909 static inline int 2910 tcp_next_pmtu(const struct icmp *icp, const struct ip *ip) 2911 { 2912 int mtu = ntohs(icp->icmp_nextmtu); 2913 2914 /* If no alternative MTU was proposed, try the next smaller one. */ 2915 if (!mtu) 2916 mtu = ip_next_mtu(ntohs(ip->ip_len), 1); 2917 if (mtu < V_tcp_minmss + sizeof(struct tcpiphdr)) 2918 mtu = V_tcp_minmss + sizeof(struct tcpiphdr); 2919 2920 return (mtu); 2921 } 2922 2923 static void 2924 tcp_ctlinput_with_port(int cmd, struct sockaddr *sa, void *vip, uint16_t port) 2925 { 2926 struct ip *ip = vip; 2927 struct tcphdr *th; 2928 struct in_addr faddr; 2929 struct inpcb *inp; 2930 struct tcpcb *tp; 2931 struct inpcb *(*notify)(struct inpcb *, int) = tcp_notify; 2932 struct icmp *icp; 2933 struct in_conninfo inc; 2934 tcp_seq icmp_tcp_seq; 2935 int mtu; 2936 2937 faddr = ((struct sockaddr_in *)sa)->sin_addr; 2938 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY) 2939 return; 2940 2941 if (cmd == PRC_MSGSIZE) 2942 notify = tcp_mtudisc_notify; 2943 else if (V_icmp_may_rst && (cmd == PRC_UNREACH_ADMIN_PROHIB || 2944 cmd == PRC_UNREACH_PORT || cmd == PRC_UNREACH_PROTOCOL || 2945 cmd == PRC_TIMXCEED_INTRANS) && ip) 2946 notify = tcp_drop_syn_sent; 2947 2948 /* 2949 * Hostdead is ugly because it goes linearly through all PCBs. 2950 * XXX: We never get this from ICMP, otherwise it makes an 2951 * excellent DoS attack on machines with many connections. 2952 */ 2953 else if (cmd == PRC_HOSTDEAD) 2954 ip = NULL; 2955 else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0) 2956 return; 2957 2958 if (ip == NULL) { 2959 in_pcbnotifyall(&V_tcbinfo, faddr, inetctlerrmap[cmd], notify); 2960 return; 2961 } 2962 2963 icp = (struct icmp *)((caddr_t)ip - offsetof(struct icmp, icmp_ip)); 2964 th = (struct tcphdr *)((caddr_t)ip + (ip->ip_hl << 2)); 2965 inp = in_pcblookup(&V_tcbinfo, faddr, th->th_dport, ip->ip_src, 2966 th->th_sport, INPLOOKUP_WLOCKPCB, NULL); 2967 if (inp != NULL && PRC_IS_REDIRECT(cmd)) { 2968 /* signal EHOSTDOWN, as it flushes the cached route */ 2969 inp = (*notify)(inp, EHOSTDOWN); 2970 goto out; 2971 } 2972 icmp_tcp_seq = th->th_seq; 2973 if (inp != NULL) { 2974 if (!(inp->inp_flags & INP_TIMEWAIT) && 2975 !(inp->inp_flags & INP_DROPPED) && 2976 !(inp->inp_socket == NULL)) { 2977 tp = intotcpcb(inp); 2978 #ifdef TCP_OFFLOAD 2979 if (tp->t_flags & TF_TOE && cmd == PRC_MSGSIZE) { 2980 /* 2981 * MTU discovery for offloaded connections. Let 2982 * the TOE driver verify seq# and process it. 2983 */ 2984 mtu = tcp_next_pmtu(icp, ip); 2985 tcp_offload_pmtu_update(tp, icmp_tcp_seq, mtu); 2986 goto out; 2987 } 2988 #endif 2989 if (tp->t_port != port) { 2990 goto out; 2991 } 2992 if (SEQ_GEQ(ntohl(icmp_tcp_seq), tp->snd_una) && 2993 SEQ_LT(ntohl(icmp_tcp_seq), tp->snd_max)) { 2994 if (cmd == PRC_MSGSIZE) { 2995 /* 2996 * MTU discovery: we got a needfrag and 2997 * will potentially try a lower MTU. 2998 */ 2999 mtu = tcp_next_pmtu(icp, ip); 3000 3001 /* 3002 * Only process the offered MTU if it 3003 * is smaller than the current one. 3004 */ 3005 if (mtu < tp->t_maxseg + 3006 sizeof(struct tcpiphdr)) { 3007 bzero(&inc, sizeof(inc)); 3008 inc.inc_faddr = faddr; 3009 inc.inc_fibnum = 3010 inp->inp_inc.inc_fibnum; 3011 tcp_hc_updatemtu(&inc, mtu); 3012 inp = tcp_mtudisc(inp, mtu); 3013 } 3014 } else 3015 inp = (*notify)(inp, 3016 inetctlerrmap[cmd]); 3017 } 3018 } 3019 } else { 3020 bzero(&inc, sizeof(inc)); 3021 inc.inc_fport = th->th_dport; 3022 inc.inc_lport = th->th_sport; 3023 inc.inc_faddr = faddr; 3024 inc.inc_laddr = ip->ip_src; 3025 syncache_unreach(&inc, icmp_tcp_seq, port); 3026 } 3027 out: 3028 if (inp != NULL) 3029 INP_WUNLOCK(inp); 3030 } 3031 3032 void 3033 tcp_ctlinput(int cmd, struct sockaddr *sa, void *vip) 3034 { 3035 tcp_ctlinput_with_port(cmd, sa, vip, htons(0)); 3036 } 3037 3038 void 3039 tcp_ctlinput_viaudp(int cmd, struct sockaddr *sa, void *vip, void *unused) 3040 { 3041 /* Its a tunneled TCP over UDP icmp */ 3042 struct ip *outer_ip, *inner_ip; 3043 struct icmp *icmp; 3044 struct udphdr *udp; 3045 struct tcphdr *th, ttemp; 3046 int i_hlen, o_len; 3047 uint16_t port; 3048 3049 inner_ip = (struct ip *)vip; 3050 icmp = (struct icmp *)((caddr_t)inner_ip - 3051 (sizeof(struct icmp) - sizeof(struct ip))); 3052 outer_ip = (struct ip *)((caddr_t)icmp - sizeof(struct ip)); 3053 i_hlen = inner_ip->ip_hl << 2; 3054 o_len = ntohs(outer_ip->ip_len); 3055 if (o_len < 3056 (sizeof(struct ip) + 8 + i_hlen + sizeof(struct udphdr) + offsetof(struct tcphdr, th_ack))) { 3057 /* Not enough data present */ 3058 return; 3059 } 3060 /* Ok lets strip out the inner udphdr header by copying up on top of it the tcp hdr */ 3061 udp = (struct udphdr *)(((caddr_t)inner_ip) + i_hlen); 3062 if (ntohs(udp->uh_sport) != V_tcp_udp_tunneling_port) { 3063 return; 3064 } 3065 port = udp->uh_dport; 3066 th = (struct tcphdr *)(udp + 1); 3067 memcpy(&ttemp, th, sizeof(struct tcphdr)); 3068 memcpy(udp, &ttemp, sizeof(struct tcphdr)); 3069 /* Now adjust down the size of the outer IP header */ 3070 o_len -= sizeof(struct udphdr); 3071 outer_ip->ip_len = htons(o_len); 3072 /* Now call in to the normal handling code */ 3073 tcp_ctlinput_with_port(cmd, sa, vip, port); 3074 } 3075 #endif /* INET */ 3076 3077 #ifdef INET6 3078 static inline int 3079 tcp6_next_pmtu(const struct icmp6_hdr *icmp6) 3080 { 3081 int mtu = ntohl(icmp6->icmp6_mtu); 3082 3083 /* 3084 * If no alternative MTU was proposed, or the proposed MTU was too 3085 * small, set to the min. 3086 */ 3087 if (mtu < IPV6_MMTU) 3088 mtu = IPV6_MMTU - 8; /* XXXNP: what is the adjustment for? */ 3089 return (mtu); 3090 } 3091 3092 static void 3093 tcp6_ctlinput_with_port(int cmd, struct sockaddr *sa, void *d, uint16_t port) 3094 { 3095 struct in6_addr *dst; 3096 struct inpcb *(*notify)(struct inpcb *, int) = tcp_notify; 3097 struct ip6_hdr *ip6; 3098 struct mbuf *m; 3099 struct inpcb *inp; 3100 struct tcpcb *tp; 3101 struct icmp6_hdr *icmp6; 3102 struct ip6ctlparam *ip6cp = NULL; 3103 const struct sockaddr_in6 *sa6_src = NULL; 3104 struct in_conninfo inc; 3105 struct tcp_ports { 3106 uint16_t th_sport; 3107 uint16_t th_dport; 3108 } t_ports; 3109 tcp_seq icmp_tcp_seq; 3110 unsigned int mtu; 3111 unsigned int off; 3112 3113 if (sa->sa_family != AF_INET6 || 3114 sa->sa_len != sizeof(struct sockaddr_in6)) 3115 return; 3116 3117 /* if the parameter is from icmp6, decode it. */ 3118 if (d != NULL) { 3119 ip6cp = (struct ip6ctlparam *)d; 3120 icmp6 = ip6cp->ip6c_icmp6; 3121 m = ip6cp->ip6c_m; 3122 ip6 = ip6cp->ip6c_ip6; 3123 off = ip6cp->ip6c_off; 3124 sa6_src = ip6cp->ip6c_src; 3125 dst = ip6cp->ip6c_finaldst; 3126 } else { 3127 m = NULL; 3128 ip6 = NULL; 3129 off = 0; /* fool gcc */ 3130 sa6_src = &sa6_any; 3131 dst = NULL; 3132 } 3133 3134 if (cmd == PRC_MSGSIZE) 3135 notify = tcp_mtudisc_notify; 3136 else if (V_icmp_may_rst && (cmd == PRC_UNREACH_ADMIN_PROHIB || 3137 cmd == PRC_UNREACH_PORT || cmd == PRC_UNREACH_PROTOCOL || 3138 cmd == PRC_TIMXCEED_INTRANS) && ip6 != NULL) 3139 notify = tcp_drop_syn_sent; 3140 3141 /* 3142 * Hostdead is ugly because it goes linearly through all PCBs. 3143 * XXX: We never get this from ICMP, otherwise it makes an 3144 * excellent DoS attack on machines with many connections. 3145 */ 3146 else if (cmd == PRC_HOSTDEAD) 3147 ip6 = NULL; 3148 else if ((unsigned)cmd >= PRC_NCMDS || inet6ctlerrmap[cmd] == 0) 3149 return; 3150 3151 if (ip6 == NULL) { 3152 in6_pcbnotify(&V_tcbinfo, sa, 0, 3153 (const struct sockaddr *)sa6_src, 3154 0, cmd, NULL, notify); 3155 return; 3156 } 3157 3158 /* Check if we can safely get the ports from the tcp hdr */ 3159 if (m == NULL || 3160 (m->m_pkthdr.len < 3161 (int32_t) (off + sizeof(struct tcp_ports)))) { 3162 return; 3163 } 3164 bzero(&t_ports, sizeof(struct tcp_ports)); 3165 m_copydata(m, off, sizeof(struct tcp_ports), (caddr_t)&t_ports); 3166 inp = in6_pcblookup(&V_tcbinfo, &ip6->ip6_dst, t_ports.th_dport, 3167 &ip6->ip6_src, t_ports.th_sport, INPLOOKUP_WLOCKPCB, NULL); 3168 if (inp != NULL && PRC_IS_REDIRECT(cmd)) { 3169 /* signal EHOSTDOWN, as it flushes the cached route */ 3170 inp = (*notify)(inp, EHOSTDOWN); 3171 goto out; 3172 } 3173 off += sizeof(struct tcp_ports); 3174 if (m->m_pkthdr.len < (int32_t) (off + sizeof(tcp_seq))) { 3175 goto out; 3176 } 3177 m_copydata(m, off, sizeof(tcp_seq), (caddr_t)&icmp_tcp_seq); 3178 if (inp != NULL) { 3179 if (!(inp->inp_flags & INP_TIMEWAIT) && 3180 !(inp->inp_flags & INP_DROPPED) && 3181 !(inp->inp_socket == NULL)) { 3182 tp = intotcpcb(inp); 3183 #ifdef TCP_OFFLOAD 3184 if (tp->t_flags & TF_TOE && cmd == PRC_MSGSIZE) { 3185 /* MTU discovery for offloaded connections. */ 3186 mtu = tcp6_next_pmtu(icmp6); 3187 tcp_offload_pmtu_update(tp, icmp_tcp_seq, mtu); 3188 goto out; 3189 } 3190 #endif 3191 if (tp->t_port != port) { 3192 goto out; 3193 } 3194 if (SEQ_GEQ(ntohl(icmp_tcp_seq), tp->snd_una) && 3195 SEQ_LT(ntohl(icmp_tcp_seq), tp->snd_max)) { 3196 if (cmd == PRC_MSGSIZE) { 3197 /* 3198 * MTU discovery: 3199 * If we got a needfrag set the MTU 3200 * in the route to the suggested new 3201 * value (if given) and then notify. 3202 */ 3203 mtu = tcp6_next_pmtu(icmp6); 3204 3205 bzero(&inc, sizeof(inc)); 3206 inc.inc_fibnum = M_GETFIB(m); 3207 inc.inc_flags |= INC_ISIPV6; 3208 inc.inc6_faddr = *dst; 3209 if (in6_setscope(&inc.inc6_faddr, 3210 m->m_pkthdr.rcvif, NULL)) 3211 goto out; 3212 /* 3213 * Only process the offered MTU if it 3214 * is smaller than the current one. 3215 */ 3216 if (mtu < tp->t_maxseg + 3217 sizeof (struct tcphdr) + 3218 sizeof (struct ip6_hdr)) { 3219 tcp_hc_updatemtu(&inc, mtu); 3220 tcp_mtudisc(inp, mtu); 3221 ICMP6STAT_INC(icp6s_pmtuchg); 3222 } 3223 } else 3224 inp = (*notify)(inp, 3225 inet6ctlerrmap[cmd]); 3226 } 3227 } 3228 } else { 3229 bzero(&inc, sizeof(inc)); 3230 inc.inc_fibnum = M_GETFIB(m); 3231 inc.inc_flags |= INC_ISIPV6; 3232 inc.inc_fport = t_ports.th_dport; 3233 inc.inc_lport = t_ports.th_sport; 3234 inc.inc6_faddr = *dst; 3235 inc.inc6_laddr = ip6->ip6_src; 3236 syncache_unreach(&inc, icmp_tcp_seq, port); 3237 } 3238 out: 3239 if (inp != NULL) 3240 INP_WUNLOCK(inp); 3241 } 3242 3243 void 3244 tcp6_ctlinput(int cmd, struct sockaddr *sa, void *d) 3245 { 3246 tcp6_ctlinput_with_port(cmd, sa, d, htons(0)); 3247 } 3248 3249 void 3250 tcp6_ctlinput_viaudp(int cmd, struct sockaddr *sa, void *d, void *unused) 3251 { 3252 struct ip6ctlparam *ip6cp; 3253 struct mbuf *m; 3254 struct udphdr *udp; 3255 uint16_t port; 3256 3257 ip6cp = (struct ip6ctlparam *)d; 3258 m = m_pulldown(ip6cp->ip6c_m, ip6cp->ip6c_off, sizeof(struct udphdr), NULL); 3259 if (m == NULL) { 3260 return; 3261 } 3262 udp = mtod(m, struct udphdr *); 3263 if (ntohs(udp->uh_sport) != V_tcp_udp_tunneling_port) { 3264 return; 3265 } 3266 port = udp->uh_dport; 3267 m_adj(m, sizeof(struct udphdr)); 3268 if ((m->m_flags & M_PKTHDR) == 0) { 3269 ip6cp->ip6c_m->m_pkthdr.len -= sizeof(struct udphdr); 3270 } 3271 /* Now call in to the normal handling code */ 3272 tcp6_ctlinput_with_port(cmd, sa, d, port); 3273 } 3274 3275 #endif /* INET6 */ 3276 3277 static uint32_t 3278 tcp_keyed_hash(struct in_conninfo *inc, u_char *key, u_int len) 3279 { 3280 SIPHASH_CTX ctx; 3281 uint32_t hash[2]; 3282 3283 KASSERT(len >= SIPHASH_KEY_LENGTH, 3284 ("%s: keylen %u too short ", __func__, len)); 3285 SipHash24_Init(&ctx); 3286 SipHash_SetKey(&ctx, (uint8_t *)key); 3287 SipHash_Update(&ctx, &inc->inc_fport, sizeof(uint16_t)); 3288 SipHash_Update(&ctx, &inc->inc_lport, sizeof(uint16_t)); 3289 switch (inc->inc_flags & INC_ISIPV6) { 3290 #ifdef INET 3291 case 0: 3292 SipHash_Update(&ctx, &inc->inc_faddr, sizeof(struct in_addr)); 3293 SipHash_Update(&ctx, &inc->inc_laddr, sizeof(struct in_addr)); 3294 break; 3295 #endif 3296 #ifdef INET6 3297 case INC_ISIPV6: 3298 SipHash_Update(&ctx, &inc->inc6_faddr, sizeof(struct in6_addr)); 3299 SipHash_Update(&ctx, &inc->inc6_laddr, sizeof(struct in6_addr)); 3300 break; 3301 #endif 3302 } 3303 SipHash_Final((uint8_t *)hash, &ctx); 3304 3305 return (hash[0] ^ hash[1]); 3306 } 3307 3308 uint32_t 3309 tcp_new_ts_offset(struct in_conninfo *inc) 3310 { 3311 struct in_conninfo inc_store, *local_inc; 3312 3313 if (!V_tcp_ts_offset_per_conn) { 3314 memcpy(&inc_store, inc, sizeof(struct in_conninfo)); 3315 inc_store.inc_lport = 0; 3316 inc_store.inc_fport = 0; 3317 local_inc = &inc_store; 3318 } else { 3319 local_inc = inc; 3320 } 3321 return (tcp_keyed_hash(local_inc, V_ts_offset_secret, 3322 sizeof(V_ts_offset_secret))); 3323 } 3324 3325 /* 3326 * Following is where TCP initial sequence number generation occurs. 3327 * 3328 * There are two places where we must use initial sequence numbers: 3329 * 1. In SYN-ACK packets. 3330 * 2. In SYN packets. 3331 * 3332 * All ISNs for SYN-ACK packets are generated by the syncache. See 3333 * tcp_syncache.c for details. 3334 * 3335 * The ISNs in SYN packets must be monotonic; TIME_WAIT recycling 3336 * depends on this property. In addition, these ISNs should be 3337 * unguessable so as to prevent connection hijacking. To satisfy 3338 * the requirements of this situation, the algorithm outlined in 3339 * RFC 1948 is used, with only small modifications. 3340 * 3341 * Implementation details: 3342 * 3343 * Time is based off the system timer, and is corrected so that it 3344 * increases by one megabyte per second. This allows for proper 3345 * recycling on high speed LANs while still leaving over an hour 3346 * before rollover. 3347 * 3348 * As reading the *exact* system time is too expensive to be done 3349 * whenever setting up a TCP connection, we increment the time 3350 * offset in two ways. First, a small random positive increment 3351 * is added to isn_offset for each connection that is set up. 3352 * Second, the function tcp_isn_tick fires once per clock tick 3353 * and increments isn_offset as necessary so that sequence numbers 3354 * are incremented at approximately ISN_BYTES_PER_SECOND. The 3355 * random positive increments serve only to ensure that the same 3356 * exact sequence number is never sent out twice (as could otherwise 3357 * happen when a port is recycled in less than the system tick 3358 * interval.) 3359 * 3360 * net.inet.tcp.isn_reseed_interval controls the number of seconds 3361 * between seeding of isn_secret. This is normally set to zero, 3362 * as reseeding should not be necessary. 3363 * 3364 * Locking of the global variables isn_secret, isn_last_reseed, isn_offset, 3365 * isn_offset_old, and isn_ctx is performed using the ISN lock. In 3366 * general, this means holding an exclusive (write) lock. 3367 */ 3368 3369 #define ISN_BYTES_PER_SECOND 1048576 3370 #define ISN_STATIC_INCREMENT 4096 3371 #define ISN_RANDOM_INCREMENT (4096 - 1) 3372 #define ISN_SECRET_LENGTH SIPHASH_KEY_LENGTH 3373 3374 VNET_DEFINE_STATIC(u_char, isn_secret[ISN_SECRET_LENGTH]); 3375 VNET_DEFINE_STATIC(int, isn_last); 3376 VNET_DEFINE_STATIC(int, isn_last_reseed); 3377 VNET_DEFINE_STATIC(u_int32_t, isn_offset); 3378 VNET_DEFINE_STATIC(u_int32_t, isn_offset_old); 3379 3380 #define V_isn_secret VNET(isn_secret) 3381 #define V_isn_last VNET(isn_last) 3382 #define V_isn_last_reseed VNET(isn_last_reseed) 3383 #define V_isn_offset VNET(isn_offset) 3384 #define V_isn_offset_old VNET(isn_offset_old) 3385 3386 tcp_seq 3387 tcp_new_isn(struct in_conninfo *inc) 3388 { 3389 tcp_seq new_isn; 3390 u_int32_t projected_offset; 3391 3392 ISN_LOCK(); 3393 /* Seed if this is the first use, reseed if requested. */ 3394 if ((V_isn_last_reseed == 0) || ((V_tcp_isn_reseed_interval > 0) && 3395 (((u_int)V_isn_last_reseed + (u_int)V_tcp_isn_reseed_interval*hz) 3396 < (u_int)ticks))) { 3397 arc4rand(&V_isn_secret, sizeof(V_isn_secret), 0); 3398 V_isn_last_reseed = ticks; 3399 } 3400 3401 /* Compute the hash and return the ISN. */ 3402 new_isn = (tcp_seq)tcp_keyed_hash(inc, V_isn_secret, 3403 sizeof(V_isn_secret)); 3404 V_isn_offset += ISN_STATIC_INCREMENT + 3405 (arc4random() & ISN_RANDOM_INCREMENT); 3406 if (ticks != V_isn_last) { 3407 projected_offset = V_isn_offset_old + 3408 ISN_BYTES_PER_SECOND / hz * (ticks - V_isn_last); 3409 if (SEQ_GT(projected_offset, V_isn_offset)) 3410 V_isn_offset = projected_offset; 3411 V_isn_offset_old = V_isn_offset; 3412 V_isn_last = ticks; 3413 } 3414 new_isn += V_isn_offset; 3415 ISN_UNLOCK(); 3416 return (new_isn); 3417 } 3418 3419 /* 3420 * When a specific ICMP unreachable message is received and the 3421 * connection state is SYN-SENT, drop the connection. This behavior 3422 * is controlled by the icmp_may_rst sysctl. 3423 */ 3424 struct inpcb * 3425 tcp_drop_syn_sent(struct inpcb *inp, int errno) 3426 { 3427 struct tcpcb *tp; 3428 3429 NET_EPOCH_ASSERT(); 3430 INP_WLOCK_ASSERT(inp); 3431 3432 if ((inp->inp_flags & INP_TIMEWAIT) || 3433 (inp->inp_flags & INP_DROPPED)) 3434 return (inp); 3435 3436 tp = intotcpcb(inp); 3437 if (tp->t_state != TCPS_SYN_SENT) 3438 return (inp); 3439 3440 if (IS_FASTOPEN(tp->t_flags)) 3441 tcp_fastopen_disable_path(tp); 3442 3443 tp = tcp_drop(tp, errno); 3444 if (tp != NULL) 3445 return (inp); 3446 else 3447 return (NULL); 3448 } 3449 3450 /* 3451 * When `need fragmentation' ICMP is received, update our idea of the MSS 3452 * based on the new value. Also nudge TCP to send something, since we 3453 * know the packet we just sent was dropped. 3454 * This duplicates some code in the tcp_mss() function in tcp_input.c. 3455 */ 3456 static struct inpcb * 3457 tcp_mtudisc_notify(struct inpcb *inp, int error) 3458 { 3459 3460 return (tcp_mtudisc(inp, -1)); 3461 } 3462 3463 static struct inpcb * 3464 tcp_mtudisc(struct inpcb *inp, int mtuoffer) 3465 { 3466 struct tcpcb *tp; 3467 struct socket *so; 3468 3469 INP_WLOCK_ASSERT(inp); 3470 if ((inp->inp_flags & INP_TIMEWAIT) || 3471 (inp->inp_flags & INP_DROPPED)) 3472 return (inp); 3473 3474 tp = intotcpcb(inp); 3475 KASSERT(tp != NULL, ("tcp_mtudisc: tp == NULL")); 3476 3477 tcp_mss_update(tp, -1, mtuoffer, NULL, NULL); 3478 3479 so = inp->inp_socket; 3480 SOCKBUF_LOCK(&so->so_snd); 3481 /* If the mss is larger than the socket buffer, decrease the mss. */ 3482 if (so->so_snd.sb_hiwat < tp->t_maxseg) 3483 tp->t_maxseg = so->so_snd.sb_hiwat; 3484 SOCKBUF_UNLOCK(&so->so_snd); 3485 3486 TCPSTAT_INC(tcps_mturesent); 3487 tp->t_rtttime = 0; 3488 tp->snd_nxt = tp->snd_una; 3489 tcp_free_sackholes(tp); 3490 tp->snd_recover = tp->snd_max; 3491 if (tp->t_flags & TF_SACK_PERMIT) 3492 EXIT_FASTRECOVERY(tp->t_flags); 3493 if (tp->t_fb->tfb_tcp_mtu_chg != NULL) { 3494 /* 3495 * Conceptually the snd_nxt setting 3496 * and freeing sack holes should 3497 * be done by the default stacks 3498 * own tfb_tcp_mtu_chg(). 3499 */ 3500 tp->t_fb->tfb_tcp_mtu_chg(tp); 3501 } 3502 if (tcp_output(tp) < 0) 3503 return (NULL); 3504 else 3505 return (inp); 3506 } 3507 3508 #ifdef INET 3509 /* 3510 * Look-up the routing entry to the peer of this inpcb. If no route 3511 * is found and it cannot be allocated, then return 0. This routine 3512 * is called by TCP routines that access the rmx structure and by 3513 * tcp_mss_update to get the peer/interface MTU. 3514 */ 3515 uint32_t 3516 tcp_maxmtu(struct in_conninfo *inc, struct tcp_ifcap *cap) 3517 { 3518 struct nhop_object *nh; 3519 struct ifnet *ifp; 3520 uint32_t maxmtu = 0; 3521 3522 KASSERT(inc != NULL, ("tcp_maxmtu with NULL in_conninfo pointer")); 3523 3524 if (inc->inc_faddr.s_addr != INADDR_ANY) { 3525 nh = fib4_lookup(inc->inc_fibnum, inc->inc_faddr, 0, NHR_NONE, 0); 3526 if (nh == NULL) 3527 return (0); 3528 3529 ifp = nh->nh_ifp; 3530 maxmtu = nh->nh_mtu; 3531 3532 /* Report additional interface capabilities. */ 3533 if (cap != NULL) { 3534 if (ifp->if_capenable & IFCAP_TSO4 && 3535 ifp->if_hwassist & CSUM_TSO) { 3536 cap->ifcap |= CSUM_TSO; 3537 cap->tsomax = ifp->if_hw_tsomax; 3538 cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount; 3539 cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize; 3540 } 3541 } 3542 } 3543 return (maxmtu); 3544 } 3545 #endif /* INET */ 3546 3547 #ifdef INET6 3548 uint32_t 3549 tcp_maxmtu6(struct in_conninfo *inc, struct tcp_ifcap *cap) 3550 { 3551 struct nhop_object *nh; 3552 struct in6_addr dst6; 3553 uint32_t scopeid; 3554 struct ifnet *ifp; 3555 uint32_t maxmtu = 0; 3556 3557 KASSERT(inc != NULL, ("tcp_maxmtu6 with NULL in_conninfo pointer")); 3558 3559 if (inc->inc_flags & INC_IPV6MINMTU) 3560 return (IPV6_MMTU); 3561 3562 if (!IN6_IS_ADDR_UNSPECIFIED(&inc->inc6_faddr)) { 3563 in6_splitscope(&inc->inc6_faddr, &dst6, &scopeid); 3564 nh = fib6_lookup(inc->inc_fibnum, &dst6, scopeid, NHR_NONE, 0); 3565 if (nh == NULL) 3566 return (0); 3567 3568 ifp = nh->nh_ifp; 3569 maxmtu = nh->nh_mtu; 3570 3571 /* Report additional interface capabilities. */ 3572 if (cap != NULL) { 3573 if (ifp->if_capenable & IFCAP_TSO6 && 3574 ifp->if_hwassist & CSUM_TSO) { 3575 cap->ifcap |= CSUM_TSO; 3576 cap->tsomax = ifp->if_hw_tsomax; 3577 cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount; 3578 cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize; 3579 } 3580 } 3581 } 3582 3583 return (maxmtu); 3584 } 3585 3586 /* 3587 * Handle setsockopt(IPV6_USE_MIN_MTU) by a TCP stack. 3588 * 3589 * XXXGL: we are updating inpcb here with INC_IPV6MINMTU flag. 3590 * The right place to do that is ip6_setpktopt() that has just been 3591 * executed. By the way it just filled ip6po_minmtu for us. 3592 */ 3593 void 3594 tcp6_use_min_mtu(struct tcpcb *tp) 3595 { 3596 struct inpcb *inp = tp->t_inpcb; 3597 3598 INP_WLOCK_ASSERT(inp); 3599 /* 3600 * In case of the IPV6_USE_MIN_MTU socket 3601 * option, the INC_IPV6MINMTU flag to announce 3602 * a corresponding MSS during the initial 3603 * handshake. If the TCP connection is not in 3604 * the front states, just reduce the MSS being 3605 * used. This avoids the sending of TCP 3606 * segments which will be fragmented at the 3607 * IPv6 layer. 3608 */ 3609 inp->inp_inc.inc_flags |= INC_IPV6MINMTU; 3610 if ((tp->t_state >= TCPS_SYN_SENT) && 3611 (inp->inp_inc.inc_flags & INC_ISIPV6)) { 3612 struct ip6_pktopts *opt; 3613 3614 opt = inp->in6p_outputopts; 3615 if (opt != NULL && opt->ip6po_minmtu == IP6PO_MINMTU_ALL && 3616 tp->t_maxseg > TCP6_MSS) 3617 tp->t_maxseg = TCP6_MSS; 3618 } 3619 } 3620 #endif /* INET6 */ 3621 3622 /* 3623 * Calculate effective SMSS per RFC5681 definition for a given TCP 3624 * connection at its current state, taking into account SACK and etc. 3625 */ 3626 u_int 3627 tcp_maxseg(const struct tcpcb *tp) 3628 { 3629 u_int optlen; 3630 3631 if (tp->t_flags & TF_NOOPT) 3632 return (tp->t_maxseg); 3633 3634 /* 3635 * Here we have a simplified code from tcp_addoptions(), 3636 * without a proper loop, and having most of paddings hardcoded. 3637 * We might make mistakes with padding here in some edge cases, 3638 * but this is harmless, since result of tcp_maxseg() is used 3639 * only in cwnd and ssthresh estimations. 3640 */ 3641 if (TCPS_HAVEESTABLISHED(tp->t_state)) { 3642 if (tp->t_flags & TF_RCVD_TSTMP) 3643 optlen = TCPOLEN_TSTAMP_APPA; 3644 else 3645 optlen = 0; 3646 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3647 if (tp->t_flags & TF_SIGNATURE) 3648 optlen += PADTCPOLEN(TCPOLEN_SIGNATURE); 3649 #endif 3650 if ((tp->t_flags & TF_SACK_PERMIT) && tp->rcv_numsacks > 0) { 3651 optlen += TCPOLEN_SACKHDR; 3652 optlen += tp->rcv_numsacks * TCPOLEN_SACK; 3653 optlen = PADTCPOLEN(optlen); 3654 } 3655 } else { 3656 if (tp->t_flags & TF_REQ_TSTMP) 3657 optlen = TCPOLEN_TSTAMP_APPA; 3658 else 3659 optlen = PADTCPOLEN(TCPOLEN_MAXSEG); 3660 if (tp->t_flags & TF_REQ_SCALE) 3661 optlen += PADTCPOLEN(TCPOLEN_WINDOW); 3662 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3663 if (tp->t_flags & TF_SIGNATURE) 3664 optlen += PADTCPOLEN(TCPOLEN_SIGNATURE); 3665 #endif 3666 if (tp->t_flags & TF_SACK_PERMIT) 3667 optlen += PADTCPOLEN(TCPOLEN_SACK_PERMITTED); 3668 } 3669 #undef PAD 3670 optlen = min(optlen, TCP_MAXOLEN); 3671 return (tp->t_maxseg - optlen); 3672 } 3673 3674 3675 u_int 3676 tcp_fixed_maxseg(const struct tcpcb *tp) 3677 { 3678 int optlen; 3679 3680 if (tp->t_flags & TF_NOOPT) 3681 return (tp->t_maxseg); 3682 3683 /* 3684 * Here we have a simplified code from tcp_addoptions(), 3685 * without a proper loop, and having most of paddings hardcoded. 3686 * We only consider fixed options that we would send every 3687 * time I.e. SACK is not considered. This is important 3688 * for cc modules to figure out what the modulo of the 3689 * cwnd should be. 3690 */ 3691 #define PAD(len) ((((len) / 4) + !!((len) % 4)) * 4) 3692 if (TCPS_HAVEESTABLISHED(tp->t_state)) { 3693 if (tp->t_flags & TF_RCVD_TSTMP) 3694 optlen = TCPOLEN_TSTAMP_APPA; 3695 else 3696 optlen = 0; 3697 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3698 if (tp->t_flags & TF_SIGNATURE) 3699 optlen += PAD(TCPOLEN_SIGNATURE); 3700 #endif 3701 } else { 3702 if (tp->t_flags & TF_REQ_TSTMP) 3703 optlen = TCPOLEN_TSTAMP_APPA; 3704 else 3705 optlen = PAD(TCPOLEN_MAXSEG); 3706 if (tp->t_flags & TF_REQ_SCALE) 3707 optlen += PAD(TCPOLEN_WINDOW); 3708 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3709 if (tp->t_flags & TF_SIGNATURE) 3710 optlen += PAD(TCPOLEN_SIGNATURE); 3711 #endif 3712 if (tp->t_flags & TF_SACK_PERMIT) 3713 optlen += PAD(TCPOLEN_SACK_PERMITTED); 3714 } 3715 #undef PAD 3716 optlen = min(optlen, TCP_MAXOLEN); 3717 return (tp->t_maxseg - optlen); 3718 } 3719 3720 3721 3722 static int 3723 sysctl_drop(SYSCTL_HANDLER_ARGS) 3724 { 3725 /* addrs[0] is a foreign socket, addrs[1] is a local one. */ 3726 struct sockaddr_storage addrs[2]; 3727 struct inpcb *inp; 3728 struct tcpcb *tp; 3729 struct tcptw *tw; 3730 struct sockaddr_in *fin, *lin; 3731 struct epoch_tracker et; 3732 #ifdef INET6 3733 struct sockaddr_in6 *fin6, *lin6; 3734 #endif 3735 int error; 3736 3737 inp = NULL; 3738 fin = lin = NULL; 3739 #ifdef INET6 3740 fin6 = lin6 = NULL; 3741 #endif 3742 error = 0; 3743 3744 if (req->oldptr != NULL || req->oldlen != 0) 3745 return (EINVAL); 3746 if (req->newptr == NULL) 3747 return (EPERM); 3748 if (req->newlen < sizeof(addrs)) 3749 return (ENOMEM); 3750 error = SYSCTL_IN(req, &addrs, sizeof(addrs)); 3751 if (error) 3752 return (error); 3753 3754 switch (addrs[0].ss_family) { 3755 #ifdef INET6 3756 case AF_INET6: 3757 fin6 = (struct sockaddr_in6 *)&addrs[0]; 3758 lin6 = (struct sockaddr_in6 *)&addrs[1]; 3759 if (fin6->sin6_len != sizeof(struct sockaddr_in6) || 3760 lin6->sin6_len != sizeof(struct sockaddr_in6)) 3761 return (EINVAL); 3762 if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr)) { 3763 if (!IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr)) 3764 return (EINVAL); 3765 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[0]); 3766 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[1]); 3767 fin = (struct sockaddr_in *)&addrs[0]; 3768 lin = (struct sockaddr_in *)&addrs[1]; 3769 break; 3770 } 3771 error = sa6_embedscope(fin6, V_ip6_use_defzone); 3772 if (error) 3773 return (error); 3774 error = sa6_embedscope(lin6, V_ip6_use_defzone); 3775 if (error) 3776 return (error); 3777 break; 3778 #endif 3779 #ifdef INET 3780 case AF_INET: 3781 fin = (struct sockaddr_in *)&addrs[0]; 3782 lin = (struct sockaddr_in *)&addrs[1]; 3783 if (fin->sin_len != sizeof(struct sockaddr_in) || 3784 lin->sin_len != sizeof(struct sockaddr_in)) 3785 return (EINVAL); 3786 break; 3787 #endif 3788 default: 3789 return (EINVAL); 3790 } 3791 NET_EPOCH_ENTER(et); 3792 switch (addrs[0].ss_family) { 3793 #ifdef INET6 3794 case AF_INET6: 3795 inp = in6_pcblookup(&V_tcbinfo, &fin6->sin6_addr, 3796 fin6->sin6_port, &lin6->sin6_addr, lin6->sin6_port, 3797 INPLOOKUP_WLOCKPCB, NULL); 3798 break; 3799 #endif 3800 #ifdef INET 3801 case AF_INET: 3802 inp = in_pcblookup(&V_tcbinfo, fin->sin_addr, fin->sin_port, 3803 lin->sin_addr, lin->sin_port, INPLOOKUP_WLOCKPCB, NULL); 3804 break; 3805 #endif 3806 } 3807 if (inp != NULL) { 3808 if (inp->inp_flags & INP_TIMEWAIT) { 3809 /* 3810 * XXXRW: There currently exists a state where an 3811 * inpcb is present, but its timewait state has been 3812 * discarded. For now, don't allow dropping of this 3813 * type of inpcb. 3814 */ 3815 tw = intotw(inp); 3816 if (tw != NULL) 3817 tcp_twclose(tw, 0); 3818 else 3819 INP_WUNLOCK(inp); 3820 } else if ((inp->inp_flags & INP_DROPPED) == 0 && 3821 !SOLISTENING(inp->inp_socket)) { 3822 tp = intotcpcb(inp); 3823 tp = tcp_drop(tp, ECONNABORTED); 3824 if (tp != NULL) 3825 INP_WUNLOCK(inp); 3826 } else 3827 INP_WUNLOCK(inp); 3828 } else 3829 error = ESRCH; 3830 NET_EPOCH_EXIT(et); 3831 return (error); 3832 } 3833 3834 SYSCTL_PROC(_net_inet_tcp, TCPCTL_DROP, drop, 3835 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | 3836 CTLFLAG_NEEDGIANT, NULL, 0, sysctl_drop, "", 3837 "Drop TCP connection"); 3838 3839 #ifdef KERN_TLS 3840 static int 3841 sysctl_switch_tls(SYSCTL_HANDLER_ARGS) 3842 { 3843 /* addrs[0] is a foreign socket, addrs[1] is a local one. */ 3844 struct sockaddr_storage addrs[2]; 3845 struct inpcb *inp; 3846 struct sockaddr_in *fin, *lin; 3847 struct epoch_tracker et; 3848 #ifdef INET6 3849 struct sockaddr_in6 *fin6, *lin6; 3850 #endif 3851 int error; 3852 3853 inp = NULL; 3854 fin = lin = NULL; 3855 #ifdef INET6 3856 fin6 = lin6 = NULL; 3857 #endif 3858 error = 0; 3859 3860 if (req->oldptr != NULL || req->oldlen != 0) 3861 return (EINVAL); 3862 if (req->newptr == NULL) 3863 return (EPERM); 3864 if (req->newlen < sizeof(addrs)) 3865 return (ENOMEM); 3866 error = SYSCTL_IN(req, &addrs, sizeof(addrs)); 3867 if (error) 3868 return (error); 3869 3870 switch (addrs[0].ss_family) { 3871 #ifdef INET6 3872 case AF_INET6: 3873 fin6 = (struct sockaddr_in6 *)&addrs[0]; 3874 lin6 = (struct sockaddr_in6 *)&addrs[1]; 3875 if (fin6->sin6_len != sizeof(struct sockaddr_in6) || 3876 lin6->sin6_len != sizeof(struct sockaddr_in6)) 3877 return (EINVAL); 3878 if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr)) { 3879 if (!IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr)) 3880 return (EINVAL); 3881 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[0]); 3882 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[1]); 3883 fin = (struct sockaddr_in *)&addrs[0]; 3884 lin = (struct sockaddr_in *)&addrs[1]; 3885 break; 3886 } 3887 error = sa6_embedscope(fin6, V_ip6_use_defzone); 3888 if (error) 3889 return (error); 3890 error = sa6_embedscope(lin6, V_ip6_use_defzone); 3891 if (error) 3892 return (error); 3893 break; 3894 #endif 3895 #ifdef INET 3896 case AF_INET: 3897 fin = (struct sockaddr_in *)&addrs[0]; 3898 lin = (struct sockaddr_in *)&addrs[1]; 3899 if (fin->sin_len != sizeof(struct sockaddr_in) || 3900 lin->sin_len != sizeof(struct sockaddr_in)) 3901 return (EINVAL); 3902 break; 3903 #endif 3904 default: 3905 return (EINVAL); 3906 } 3907 NET_EPOCH_ENTER(et); 3908 switch (addrs[0].ss_family) { 3909 #ifdef INET6 3910 case AF_INET6: 3911 inp = in6_pcblookup(&V_tcbinfo, &fin6->sin6_addr, 3912 fin6->sin6_port, &lin6->sin6_addr, lin6->sin6_port, 3913 INPLOOKUP_WLOCKPCB, NULL); 3914 break; 3915 #endif 3916 #ifdef INET 3917 case AF_INET: 3918 inp = in_pcblookup(&V_tcbinfo, fin->sin_addr, fin->sin_port, 3919 lin->sin_addr, lin->sin_port, INPLOOKUP_WLOCKPCB, NULL); 3920 break; 3921 #endif 3922 } 3923 NET_EPOCH_EXIT(et); 3924 if (inp != NULL) { 3925 if ((inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) != 0 || 3926 inp->inp_socket == NULL) { 3927 error = ECONNRESET; 3928 INP_WUNLOCK(inp); 3929 } else { 3930 struct socket *so; 3931 3932 so = inp->inp_socket; 3933 soref(so); 3934 error = ktls_set_tx_mode(so, 3935 arg2 == 0 ? TCP_TLS_MODE_SW : TCP_TLS_MODE_IFNET); 3936 INP_WUNLOCK(inp); 3937 sorele(so); 3938 } 3939 } else 3940 error = ESRCH; 3941 return (error); 3942 } 3943 3944 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, switch_to_sw_tls, 3945 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | 3946 CTLFLAG_NEEDGIANT, NULL, 0, sysctl_switch_tls, "", 3947 "Switch TCP connection to SW TLS"); 3948 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, switch_to_ifnet_tls, 3949 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | 3950 CTLFLAG_NEEDGIANT, NULL, 1, sysctl_switch_tls, "", 3951 "Switch TCP connection to ifnet TLS"); 3952 #endif 3953 3954 /* 3955 * Generate a standardized TCP log line for use throughout the 3956 * tcp subsystem. Memory allocation is done with M_NOWAIT to 3957 * allow use in the interrupt context. 3958 * 3959 * NB: The caller MUST free(s, M_TCPLOG) the returned string. 3960 * NB: The function may return NULL if memory allocation failed. 3961 * 3962 * Due to header inclusion and ordering limitations the struct ip 3963 * and ip6_hdr pointers have to be passed as void pointers. 3964 */ 3965 char * 3966 tcp_log_vain(struct in_conninfo *inc, struct tcphdr *th, void *ip4hdr, 3967 const void *ip6hdr) 3968 { 3969 3970 /* Is logging enabled? */ 3971 if (V_tcp_log_in_vain == 0) 3972 return (NULL); 3973 3974 return (tcp_log_addr(inc, th, ip4hdr, ip6hdr)); 3975 } 3976 3977 char * 3978 tcp_log_addrs(struct in_conninfo *inc, struct tcphdr *th, void *ip4hdr, 3979 const void *ip6hdr) 3980 { 3981 3982 /* Is logging enabled? */ 3983 if (tcp_log_debug == 0) 3984 return (NULL); 3985 3986 return (tcp_log_addr(inc, th, ip4hdr, ip6hdr)); 3987 } 3988 3989 static char * 3990 tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th, void *ip4hdr, 3991 const void *ip6hdr) 3992 { 3993 char *s, *sp; 3994 size_t size; 3995 struct ip *ip; 3996 #ifdef INET6 3997 const struct ip6_hdr *ip6; 3998 3999 ip6 = (const struct ip6_hdr *)ip6hdr; 4000 #endif /* INET6 */ 4001 ip = (struct ip *)ip4hdr; 4002 4003 /* 4004 * The log line looks like this: 4005 * "TCP: [1.2.3.4]:50332 to [1.2.3.4]:80 tcpflags 0x2<SYN>" 4006 */ 4007 size = sizeof("TCP: []:12345 to []:12345 tcpflags 0x2<>") + 4008 sizeof(PRINT_TH_FLAGS) + 1 + 4009 #ifdef INET6 4010 2 * INET6_ADDRSTRLEN; 4011 #else 4012 2 * INET_ADDRSTRLEN; 4013 #endif /* INET6 */ 4014 4015 s = malloc(size, M_TCPLOG, M_ZERO|M_NOWAIT); 4016 if (s == NULL) 4017 return (NULL); 4018 4019 strcat(s, "TCP: ["); 4020 sp = s + strlen(s); 4021 4022 if (inc && ((inc->inc_flags & INC_ISIPV6) == 0)) { 4023 inet_ntoa_r(inc->inc_faddr, sp); 4024 sp = s + strlen(s); 4025 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport)); 4026 sp = s + strlen(s); 4027 inet_ntoa_r(inc->inc_laddr, sp); 4028 sp = s + strlen(s); 4029 sprintf(sp, "]:%i", ntohs(inc->inc_lport)); 4030 #ifdef INET6 4031 } else if (inc) { 4032 ip6_sprintf(sp, &inc->inc6_faddr); 4033 sp = s + strlen(s); 4034 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport)); 4035 sp = s + strlen(s); 4036 ip6_sprintf(sp, &inc->inc6_laddr); 4037 sp = s + strlen(s); 4038 sprintf(sp, "]:%i", ntohs(inc->inc_lport)); 4039 } else if (ip6 && th) { 4040 ip6_sprintf(sp, &ip6->ip6_src); 4041 sp = s + strlen(s); 4042 sprintf(sp, "]:%i to [", ntohs(th->th_sport)); 4043 sp = s + strlen(s); 4044 ip6_sprintf(sp, &ip6->ip6_dst); 4045 sp = s + strlen(s); 4046 sprintf(sp, "]:%i", ntohs(th->th_dport)); 4047 #endif /* INET6 */ 4048 #ifdef INET 4049 } else if (ip && th) { 4050 inet_ntoa_r(ip->ip_src, sp); 4051 sp = s + strlen(s); 4052 sprintf(sp, "]:%i to [", ntohs(th->th_sport)); 4053 sp = s + strlen(s); 4054 inet_ntoa_r(ip->ip_dst, sp); 4055 sp = s + strlen(s); 4056 sprintf(sp, "]:%i", ntohs(th->th_dport)); 4057 #endif /* INET */ 4058 } else { 4059 free(s, M_TCPLOG); 4060 return (NULL); 4061 } 4062 sp = s + strlen(s); 4063 if (th) 4064 sprintf(sp, " tcpflags 0x%b", th->th_flags, PRINT_TH_FLAGS); 4065 if (*(s + size - 1) != '\0') 4066 panic("%s: string too long", __func__); 4067 return (s); 4068 } 4069 4070 /* 4071 * A subroutine which makes it easy to track TCP state changes with DTrace. 4072 * This function shouldn't be called for t_state initializations that don't 4073 * correspond to actual TCP state transitions. 4074 */ 4075 void 4076 tcp_state_change(struct tcpcb *tp, int newstate) 4077 { 4078 #if defined(KDTRACE_HOOKS) 4079 int pstate = tp->t_state; 4080 #endif 4081 4082 TCPSTATES_DEC(tp->t_state); 4083 TCPSTATES_INC(newstate); 4084 tp->t_state = newstate; 4085 TCP_PROBE6(state__change, NULL, tp, NULL, tp, NULL, pstate); 4086 } 4087 4088 /* 4089 * Create an external-format (``xtcpcb'') structure using the information in 4090 * the kernel-format tcpcb structure pointed to by tp. This is done to 4091 * reduce the spew of irrelevant information over this interface, to isolate 4092 * user code from changes in the kernel structure, and potentially to provide 4093 * information-hiding if we decide that some of this information should be 4094 * hidden from users. 4095 */ 4096 void 4097 tcp_inptoxtp(const struct inpcb *inp, struct xtcpcb *xt) 4098 { 4099 struct tcpcb *tp = intotcpcb(inp); 4100 struct tcptw *tw = intotw(inp); 4101 sbintime_t now; 4102 4103 bzero(xt, sizeof(*xt)); 4104 if (inp->inp_flags & INP_TIMEWAIT) { 4105 xt->t_state = TCPS_TIME_WAIT; 4106 xt->xt_encaps_port = tw->t_port; 4107 } else { 4108 xt->t_state = tp->t_state; 4109 xt->t_logstate = tp->t_logstate; 4110 xt->t_flags = tp->t_flags; 4111 xt->t_sndzerowin = tp->t_sndzerowin; 4112 xt->t_sndrexmitpack = tp->t_sndrexmitpack; 4113 xt->t_rcvoopack = tp->t_rcvoopack; 4114 xt->t_rcv_wnd = tp->rcv_wnd; 4115 xt->t_snd_wnd = tp->snd_wnd; 4116 xt->t_snd_cwnd = tp->snd_cwnd; 4117 xt->t_snd_ssthresh = tp->snd_ssthresh; 4118 xt->t_dsack_bytes = tp->t_dsack_bytes; 4119 xt->t_dsack_tlp_bytes = tp->t_dsack_tlp_bytes; 4120 xt->t_dsack_pack = tp->t_dsack_pack; 4121 xt->t_maxseg = tp->t_maxseg; 4122 xt->xt_ecn = (tp->t_flags2 & TF2_ECN_PERMIT) ? 1 : 0 + 4123 (tp->t_flags2 & TF2_ACE_PERMIT) ? 2 : 0; 4124 4125 now = getsbinuptime(); 4126 #define COPYTIMER(ttt) do { \ 4127 if (callout_active(&tp->t_timers->ttt)) \ 4128 xt->ttt = (tp->t_timers->ttt.c_time - now) / \ 4129 SBT_1MS; \ 4130 else \ 4131 xt->ttt = 0; \ 4132 } while (0) 4133 COPYTIMER(tt_delack); 4134 COPYTIMER(tt_rexmt); 4135 COPYTIMER(tt_persist); 4136 COPYTIMER(tt_keep); 4137 COPYTIMER(tt_2msl); 4138 #undef COPYTIMER 4139 xt->t_rcvtime = 1000 * (ticks - tp->t_rcvtime) / hz; 4140 4141 xt->xt_encaps_port = tp->t_port; 4142 bcopy(tp->t_fb->tfb_tcp_block_name, xt->xt_stack, 4143 TCP_FUNCTION_NAME_LEN_MAX); 4144 bcopy(CC_ALGO(tp)->name, xt->xt_cc, 4145 TCP_CA_NAME_MAX); 4146 #ifdef TCP_BLACKBOX 4147 (void)tcp_log_get_id(tp, xt->xt_logid); 4148 #endif 4149 } 4150 4151 xt->xt_len = sizeof(struct xtcpcb); 4152 in_pcbtoxinpcb(inp, &xt->xt_inp); 4153 if (inp->inp_socket == NULL) 4154 xt->xt_inp.xi_socket.xso_protocol = IPPROTO_TCP; 4155 } 4156 4157 void 4158 tcp_log_end_status(struct tcpcb *tp, uint8_t status) 4159 { 4160 uint32_t bit, i; 4161 4162 if ((tp == NULL) || 4163 (status > TCP_EI_STATUS_MAX_VALUE) || 4164 (status == 0)) { 4165 /* Invalid */ 4166 return; 4167 } 4168 if (status > (sizeof(uint32_t) * 8)) { 4169 /* Should this be a KASSERT? */ 4170 return; 4171 } 4172 bit = 1U << (status - 1); 4173 if (bit & tp->t_end_info_status) { 4174 /* already logged */ 4175 return; 4176 } 4177 for (i = 0; i < TCP_END_BYTE_INFO; i++) { 4178 if (tp->t_end_info_bytes[i] == TCP_EI_EMPTY_SLOT) { 4179 tp->t_end_info_bytes[i] = status; 4180 tp->t_end_info_status |= bit; 4181 break; 4182 } 4183 } 4184 } 4185 4186 int 4187 tcp_can_enable_pacing(void) 4188 { 4189 4190 if ((tcp_pacing_limit == -1) || 4191 (tcp_pacing_limit > number_of_tcp_connections_pacing)) { 4192 atomic_fetchadd_int(&number_of_tcp_connections_pacing, 1); 4193 shadow_num_connections = number_of_tcp_connections_pacing; 4194 return (1); 4195 } else { 4196 return (0); 4197 } 4198 } 4199 4200 static uint8_t tcp_pacing_warning = 0; 4201 4202 void 4203 tcp_decrement_paced_conn(void) 4204 { 4205 uint32_t ret; 4206 4207 ret = atomic_fetchadd_int(&number_of_tcp_connections_pacing, -1); 4208 shadow_num_connections = number_of_tcp_connections_pacing; 4209 KASSERT(ret != 0, ("tcp_paced_connection_exits -1 would cause wrap?")); 4210 if (ret == 0) { 4211 if (tcp_pacing_limit != -1) { 4212 printf("Warning all pacing is now disabled, count decrements invalidly!\n"); 4213 tcp_pacing_limit = 0; 4214 } else if (tcp_pacing_warning == 0) { 4215 printf("Warning pacing count is invalid, invalid decrement\n"); 4216 tcp_pacing_warning = 1; 4217 } 4218 } 4219 } 4220