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 void 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_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 /* 1150 * TCP initialization. 1151 */ 1152 static void 1153 tcp_zone_change(void *tag) 1154 { 1155 1156 uma_zone_set_max(V_tcbinfo.ipi_zone, maxsockets); 1157 uma_zone_set_max(V_tcpcb_zone, maxsockets); 1158 tcp_tw_zone_change(); 1159 } 1160 1161 static int 1162 tcp_inpcb_init(void *mem, int size, int flags) 1163 { 1164 struct inpcb *inp = mem; 1165 1166 INP_LOCK_INIT(inp, "inp", "tcpinp"); 1167 return (0); 1168 } 1169 1170 /* 1171 * Take a value and get the next power of 2 that doesn't overflow. 1172 * Used to size the tcp_inpcb hash buckets. 1173 */ 1174 static int 1175 maketcp_hashsize(int size) 1176 { 1177 int hashsize; 1178 1179 /* 1180 * auto tune. 1181 * get the next power of 2 higher than maxsockets. 1182 */ 1183 hashsize = 1 << fls(size); 1184 /* catch overflow, and just go one power of 2 smaller */ 1185 if (hashsize < size) { 1186 hashsize = 1 << (fls(size) - 1); 1187 } 1188 return (hashsize); 1189 } 1190 1191 static volatile int next_tcp_stack_id = 1; 1192 1193 /* 1194 * Register a TCP function block with the name provided in the names 1195 * array. (Note that this function does NOT automatically register 1196 * blk->tfb_tcp_block_name as a stack name. Therefore, you should 1197 * explicitly include blk->tfb_tcp_block_name in the list of names if 1198 * you wish to register the stack with that name.) 1199 * 1200 * Either all name registrations will succeed or all will fail. If 1201 * a name registration fails, the function will update the num_names 1202 * argument to point to the array index of the name that encountered 1203 * the failure. 1204 * 1205 * Returns 0 on success, or an error code on failure. 1206 */ 1207 int 1208 register_tcp_functions_as_names(struct tcp_function_block *blk, int wait, 1209 const char *names[], int *num_names) 1210 { 1211 struct tcp_function *n; 1212 struct tcp_function_set fs; 1213 int error, i; 1214 1215 KASSERT(names != NULL && *num_names > 0, 1216 ("%s: Called with 0-length name list", __func__)); 1217 KASSERT(names != NULL, ("%s: Called with NULL name list", __func__)); 1218 KASSERT(rw_initialized(&tcp_function_lock), 1219 ("%s: called too early", __func__)); 1220 1221 if ((blk->tfb_tcp_output == NULL) || 1222 (blk->tfb_tcp_do_segment == NULL) || 1223 (blk->tfb_tcp_ctloutput == NULL) || 1224 (strlen(blk->tfb_tcp_block_name) == 0)) { 1225 /* 1226 * These functions are required and you 1227 * need a name. 1228 */ 1229 *num_names = 0; 1230 return (EINVAL); 1231 } 1232 if (blk->tfb_tcp_timer_stop_all || 1233 blk->tfb_tcp_timer_activate || 1234 blk->tfb_tcp_timer_active || 1235 blk->tfb_tcp_timer_stop) { 1236 /* 1237 * If you define one timer function you 1238 * must have them all. 1239 */ 1240 if ((blk->tfb_tcp_timer_stop_all == NULL) || 1241 (blk->tfb_tcp_timer_activate == NULL) || 1242 (blk->tfb_tcp_timer_active == NULL) || 1243 (blk->tfb_tcp_timer_stop == NULL)) { 1244 *num_names = 0; 1245 return (EINVAL); 1246 } 1247 } 1248 1249 if (blk->tfb_flags & TCP_FUNC_BEING_REMOVED) { 1250 *num_names = 0; 1251 return (EINVAL); 1252 } 1253 1254 refcount_init(&blk->tfb_refcnt, 0); 1255 blk->tfb_id = atomic_fetchadd_int(&next_tcp_stack_id, 1); 1256 for (i = 0; i < *num_names; i++) { 1257 n = malloc(sizeof(struct tcp_function), M_TCPFUNCTIONS, wait); 1258 if (n == NULL) { 1259 error = ENOMEM; 1260 goto cleanup; 1261 } 1262 n->tf_fb = blk; 1263 1264 (void)strlcpy(fs.function_set_name, names[i], 1265 sizeof(fs.function_set_name)); 1266 rw_wlock(&tcp_function_lock); 1267 if (find_tcp_functions_locked(&fs) != NULL) { 1268 /* Duplicate name space not allowed */ 1269 rw_wunlock(&tcp_function_lock); 1270 free(n, M_TCPFUNCTIONS); 1271 error = EALREADY; 1272 goto cleanup; 1273 } 1274 (void)strlcpy(n->tf_name, names[i], sizeof(n->tf_name)); 1275 TAILQ_INSERT_TAIL(&t_functions, n, tf_next); 1276 tcp_fb_cnt++; 1277 rw_wunlock(&tcp_function_lock); 1278 } 1279 return(0); 1280 1281 cleanup: 1282 /* 1283 * Deregister the names we just added. Because registration failed 1284 * for names[i], we don't need to deregister that name. 1285 */ 1286 *num_names = i; 1287 rw_wlock(&tcp_function_lock); 1288 while (--i >= 0) { 1289 TAILQ_FOREACH(n, &t_functions, tf_next) { 1290 if (!strncmp(n->tf_name, names[i], 1291 TCP_FUNCTION_NAME_LEN_MAX)) { 1292 TAILQ_REMOVE(&t_functions, n, tf_next); 1293 tcp_fb_cnt--; 1294 n->tf_fb = NULL; 1295 free(n, M_TCPFUNCTIONS); 1296 break; 1297 } 1298 } 1299 } 1300 rw_wunlock(&tcp_function_lock); 1301 return (error); 1302 } 1303 1304 /* 1305 * Register a TCP function block using the name provided in the name 1306 * argument. 1307 * 1308 * Returns 0 on success, or an error code on failure. 1309 */ 1310 int 1311 register_tcp_functions_as_name(struct tcp_function_block *blk, const char *name, 1312 int wait) 1313 { 1314 const char *name_list[1]; 1315 int num_names, rv; 1316 1317 num_names = 1; 1318 if (name != NULL) 1319 name_list[0] = name; 1320 else 1321 name_list[0] = blk->tfb_tcp_block_name; 1322 rv = register_tcp_functions_as_names(blk, wait, name_list, &num_names); 1323 return (rv); 1324 } 1325 1326 /* 1327 * Register a TCP function block using the name defined in 1328 * blk->tfb_tcp_block_name. 1329 * 1330 * Returns 0 on success, or an error code on failure. 1331 */ 1332 int 1333 register_tcp_functions(struct tcp_function_block *blk, int wait) 1334 { 1335 1336 return (register_tcp_functions_as_name(blk, NULL, wait)); 1337 } 1338 1339 /* 1340 * Deregister all names associated with a function block. This 1341 * functionally removes the function block from use within the system. 1342 * 1343 * When called with a true quiesce argument, mark the function block 1344 * as being removed so no more stacks will use it and determine 1345 * whether the removal would succeed. 1346 * 1347 * When called with a false quiesce argument, actually attempt the 1348 * removal. 1349 * 1350 * When called with a force argument, attempt to switch all TCBs to 1351 * use the default stack instead of returning EBUSY. 1352 * 1353 * Returns 0 on success (or if the removal would succeed, or an error 1354 * code on failure. 1355 */ 1356 int 1357 deregister_tcp_functions(struct tcp_function_block *blk, bool quiesce, 1358 bool force) 1359 { 1360 struct tcp_function *f; 1361 1362 if (blk == &tcp_def_funcblk) { 1363 /* You can't un-register the default */ 1364 return (EPERM); 1365 } 1366 rw_wlock(&tcp_function_lock); 1367 if (blk == tcp_func_set_ptr) { 1368 /* You can't free the current default */ 1369 rw_wunlock(&tcp_function_lock); 1370 return (EBUSY); 1371 } 1372 /* Mark the block so no more stacks can use it. */ 1373 blk->tfb_flags |= TCP_FUNC_BEING_REMOVED; 1374 /* 1375 * If TCBs are still attached to the stack, attempt to switch them 1376 * to the default stack. 1377 */ 1378 if (force && blk->tfb_refcnt) { 1379 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, 1380 INPLOOKUP_WLOCKPCB); 1381 struct inpcb *inp; 1382 struct tcpcb *tp; 1383 VNET_ITERATOR_DECL(vnet_iter); 1384 1385 rw_wunlock(&tcp_function_lock); 1386 1387 VNET_LIST_RLOCK(); 1388 VNET_FOREACH(vnet_iter) { 1389 CURVNET_SET(vnet_iter); 1390 while ((inp = inp_next(&inpi)) != NULL) { 1391 if (inp->inp_flags & INP_TIMEWAIT) 1392 continue; 1393 tp = intotcpcb(inp); 1394 if (tp == NULL || tp->t_fb != blk) 1395 continue; 1396 tcp_switch_back_to_default(tp); 1397 } 1398 CURVNET_RESTORE(); 1399 } 1400 VNET_LIST_RUNLOCK(); 1401 1402 rw_wlock(&tcp_function_lock); 1403 } 1404 if (blk->tfb_refcnt) { 1405 /* TCBs still attached. */ 1406 rw_wunlock(&tcp_function_lock); 1407 return (EBUSY); 1408 } 1409 if (quiesce) { 1410 /* Skip removal. */ 1411 rw_wunlock(&tcp_function_lock); 1412 return (0); 1413 } 1414 /* Remove any function names that map to this function block. */ 1415 while (find_tcp_fb_locked(blk, &f) != NULL) { 1416 TAILQ_REMOVE(&t_functions, f, tf_next); 1417 tcp_fb_cnt--; 1418 f->tf_fb = NULL; 1419 free(f, M_TCPFUNCTIONS); 1420 } 1421 rw_wunlock(&tcp_function_lock); 1422 return (0); 1423 } 1424 1425 void 1426 tcp_init(void) 1427 { 1428 const char *tcbhash_tuneable; 1429 int hashsize; 1430 1431 tcbhash_tuneable = "net.inet.tcp.tcbhashsize"; 1432 1433 #ifdef TCP_HHOOK 1434 if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN, 1435 &V_tcp_hhh[HHOOK_TCP_EST_IN], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0) 1436 printf("%s: WARNING: unable to register helper hook\n", __func__); 1437 if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT, 1438 &V_tcp_hhh[HHOOK_TCP_EST_OUT], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0) 1439 printf("%s: WARNING: unable to register helper hook\n", __func__); 1440 #endif 1441 #ifdef STATS 1442 if (tcp_stats_init()) 1443 printf("%s: WARNING: unable to initialise TCP stats\n", 1444 __func__); 1445 #endif 1446 hashsize = TCBHASHSIZE; 1447 TUNABLE_INT_FETCH(tcbhash_tuneable, &hashsize); 1448 if (hashsize == 0) { 1449 /* 1450 * Auto tune the hash size based on maxsockets. 1451 * A perfect hash would have a 1:1 mapping 1452 * (hashsize = maxsockets) however it's been 1453 * suggested that O(2) average is better. 1454 */ 1455 hashsize = maketcp_hashsize(maxsockets / 4); 1456 /* 1457 * Our historical default is 512, 1458 * do not autotune lower than this. 1459 */ 1460 if (hashsize < 512) 1461 hashsize = 512; 1462 if (bootverbose && IS_DEFAULT_VNET(curvnet)) 1463 printf("%s: %s auto tuned to %d\n", __func__, 1464 tcbhash_tuneable, hashsize); 1465 } 1466 /* 1467 * We require a hashsize to be a power of two. 1468 * Previously if it was not a power of two we would just reset it 1469 * back to 512, which could be a nasty surprise if you did not notice 1470 * the error message. 1471 * Instead what we do is clip it to the closest power of two lower 1472 * than the specified hash value. 1473 */ 1474 if (!powerof2(hashsize)) { 1475 int oldhashsize = hashsize; 1476 1477 hashsize = maketcp_hashsize(hashsize); 1478 /* prevent absurdly low value */ 1479 if (hashsize < 16) 1480 hashsize = 16; 1481 printf("%s: WARNING: TCB hash size not a power of 2, " 1482 "clipped from %d to %d.\n", __func__, oldhashsize, 1483 hashsize); 1484 } 1485 in_pcbinfo_init(&V_tcbinfo, "tcp", hashsize, hashsize, 1486 "tcp_inpcb", tcp_inpcb_init); 1487 1488 /* 1489 * These have to be type stable for the benefit of the timers. 1490 */ 1491 V_tcpcb_zone = uma_zcreate("tcpcb", sizeof(struct tcpcb_mem), 1492 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 1493 uma_zone_set_max(V_tcpcb_zone, maxsockets); 1494 uma_zone_set_warning(V_tcpcb_zone, "kern.ipc.maxsockets limit reached"); 1495 1496 tcp_tw_init(); 1497 syncache_init(); 1498 tcp_hc_init(); 1499 1500 TUNABLE_INT_FETCH("net.inet.tcp.sack.enable", &V_tcp_do_sack); 1501 V_sack_hole_zone = uma_zcreate("sackhole", sizeof(struct sackhole), 1502 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 1503 1504 tcp_fastopen_init(); 1505 1506 COUNTER_ARRAY_ALLOC(V_tcps_states, TCP_NSTATES, M_WAITOK); 1507 VNET_PCPUSTAT_ALLOC(tcpstat, M_WAITOK); 1508 1509 /* Skip initialization of globals for non-default instances. */ 1510 if (!IS_DEFAULT_VNET(curvnet)) 1511 return; 1512 1513 tcp_reass_global_init(); 1514 1515 /* XXX virtualize those bellow? */ 1516 tcp_delacktime = TCPTV_DELACK; 1517 tcp_keepinit = TCPTV_KEEP_INIT; 1518 tcp_keepidle = TCPTV_KEEP_IDLE; 1519 tcp_keepintvl = TCPTV_KEEPINTVL; 1520 tcp_maxpersistidle = TCPTV_KEEP_IDLE; 1521 tcp_msl = TCPTV_MSL; 1522 tcp_rexmit_initial = TCPTV_RTOBASE; 1523 if (tcp_rexmit_initial < 1) 1524 tcp_rexmit_initial = 1; 1525 tcp_rexmit_min = TCPTV_MIN; 1526 if (tcp_rexmit_min < 1) 1527 tcp_rexmit_min = 1; 1528 tcp_persmin = TCPTV_PERSMIN; 1529 tcp_persmax = TCPTV_PERSMAX; 1530 tcp_rexmit_slop = TCPTV_CPU_VAR; 1531 tcp_finwait2_timeout = TCPTV_FINWAIT2_TIMEOUT; 1532 tcp_tcbhashsize = hashsize; 1533 1534 /* Setup the tcp function block list */ 1535 TAILQ_INIT(&t_functions); 1536 rw_init(&tcp_function_lock, "tcp_func_lock"); 1537 register_tcp_functions(&tcp_def_funcblk, M_WAITOK); 1538 #ifdef TCP_BLACKBOX 1539 /* Initialize the TCP logging data. */ 1540 tcp_log_init(); 1541 #endif 1542 arc4rand(&V_ts_offset_secret, sizeof(V_ts_offset_secret), 0); 1543 1544 if (tcp_soreceive_stream) { 1545 #ifdef INET 1546 tcp_usrreqs.pru_soreceive = soreceive_stream; 1547 #endif 1548 #ifdef INET6 1549 tcp6_usrreqs.pru_soreceive = soreceive_stream; 1550 #endif /* INET6 */ 1551 } 1552 1553 #ifdef INET6 1554 #define TCP_MINPROTOHDR (sizeof(struct ip6_hdr) + sizeof(struct tcphdr)) 1555 #else /* INET6 */ 1556 #define TCP_MINPROTOHDR (sizeof(struct tcpiphdr)) 1557 #endif /* INET6 */ 1558 if (max_protohdr < TCP_MINPROTOHDR) 1559 max_protohdr = TCP_MINPROTOHDR; 1560 if (max_linkhdr + TCP_MINPROTOHDR > MHLEN) 1561 panic("tcp_init"); 1562 #undef TCP_MINPROTOHDR 1563 1564 ISN_LOCK_INIT(); 1565 EVENTHANDLER_REGISTER(shutdown_pre_sync, tcp_fini, NULL, 1566 SHUTDOWN_PRI_DEFAULT); 1567 EVENTHANDLER_REGISTER(maxsockets_change, tcp_zone_change, NULL, 1568 EVENTHANDLER_PRI_ANY); 1569 1570 tcp_inp_lro_direct_queue = counter_u64_alloc(M_WAITOK); 1571 tcp_inp_lro_wokeup_queue = counter_u64_alloc(M_WAITOK); 1572 tcp_inp_lro_compressed = counter_u64_alloc(M_WAITOK); 1573 tcp_inp_lro_locks_taken = counter_u64_alloc(M_WAITOK); 1574 tcp_extra_mbuf = counter_u64_alloc(M_WAITOK); 1575 tcp_would_have_but = counter_u64_alloc(M_WAITOK); 1576 tcp_comp_total = counter_u64_alloc(M_WAITOK); 1577 tcp_uncomp_total = counter_u64_alloc(M_WAITOK); 1578 tcp_bad_csums = counter_u64_alloc(M_WAITOK); 1579 #ifdef TCPPCAP 1580 tcp_pcap_init(); 1581 #endif 1582 } 1583 1584 #ifdef VIMAGE 1585 static void 1586 tcp_destroy(void *unused __unused) 1587 { 1588 int n; 1589 #ifdef TCP_HHOOK 1590 int error; 1591 #endif 1592 1593 /* 1594 * All our processes are gone, all our sockets should be cleaned 1595 * up, which means, we should be past the tcp_discardcb() calls. 1596 * Sleep to let all tcpcb timers really disappear and cleanup. 1597 */ 1598 for (;;) { 1599 INP_INFO_WLOCK(&V_tcbinfo); 1600 n = V_tcbinfo.ipi_count; 1601 INP_INFO_WUNLOCK(&V_tcbinfo); 1602 if (n == 0) 1603 break; 1604 pause("tcpdes", hz / 10); 1605 } 1606 tcp_hc_destroy(); 1607 syncache_destroy(); 1608 tcp_tw_destroy(); 1609 in_pcbinfo_destroy(&V_tcbinfo); 1610 /* tcp_discardcb() clears the sack_holes up. */ 1611 uma_zdestroy(V_sack_hole_zone); 1612 uma_zdestroy(V_tcpcb_zone); 1613 1614 /* 1615 * Cannot free the zone until all tcpcbs are released as we attach 1616 * the allocations to them. 1617 */ 1618 tcp_fastopen_destroy(); 1619 1620 COUNTER_ARRAY_FREE(V_tcps_states, TCP_NSTATES); 1621 VNET_PCPUSTAT_FREE(tcpstat); 1622 1623 #ifdef TCP_HHOOK 1624 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_IN]); 1625 if (error != 0) { 1626 printf("%s: WARNING: unable to deregister helper hook " 1627 "type=%d, id=%d: error %d returned\n", __func__, 1628 HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN, error); 1629 } 1630 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_OUT]); 1631 if (error != 0) { 1632 printf("%s: WARNING: unable to deregister helper hook " 1633 "type=%d, id=%d: error %d returned\n", __func__, 1634 HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT, error); 1635 } 1636 #endif 1637 } 1638 VNET_SYSUNINIT(tcp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, tcp_destroy, NULL); 1639 #endif 1640 1641 void 1642 tcp_fini(void *xtp) 1643 { 1644 1645 } 1646 1647 /* 1648 * Fill in the IP and TCP headers for an outgoing packet, given the tcpcb. 1649 * tcp_template used to store this data in mbufs, but we now recopy it out 1650 * of the tcpcb each time to conserve mbufs. 1651 */ 1652 void 1653 tcpip_fillheaders(struct inpcb *inp, uint16_t port, void *ip_ptr, void *tcp_ptr) 1654 { 1655 struct tcphdr *th = (struct tcphdr *)tcp_ptr; 1656 1657 INP_WLOCK_ASSERT(inp); 1658 1659 #ifdef INET6 1660 if ((inp->inp_vflag & INP_IPV6) != 0) { 1661 struct ip6_hdr *ip6; 1662 1663 ip6 = (struct ip6_hdr *)ip_ptr; 1664 ip6->ip6_flow = (ip6->ip6_flow & ~IPV6_FLOWINFO_MASK) | 1665 (inp->inp_flow & IPV6_FLOWINFO_MASK); 1666 ip6->ip6_vfc = (ip6->ip6_vfc & ~IPV6_VERSION_MASK) | 1667 (IPV6_VERSION & IPV6_VERSION_MASK); 1668 if (port == 0) 1669 ip6->ip6_nxt = IPPROTO_TCP; 1670 else 1671 ip6->ip6_nxt = IPPROTO_UDP; 1672 ip6->ip6_plen = htons(sizeof(struct tcphdr)); 1673 ip6->ip6_src = inp->in6p_laddr; 1674 ip6->ip6_dst = inp->in6p_faddr; 1675 } 1676 #endif /* INET6 */ 1677 #if defined(INET6) && defined(INET) 1678 else 1679 #endif 1680 #ifdef INET 1681 { 1682 struct ip *ip; 1683 1684 ip = (struct ip *)ip_ptr; 1685 ip->ip_v = IPVERSION; 1686 ip->ip_hl = 5; 1687 ip->ip_tos = inp->inp_ip_tos; 1688 ip->ip_len = 0; 1689 ip->ip_id = 0; 1690 ip->ip_off = 0; 1691 ip->ip_ttl = inp->inp_ip_ttl; 1692 ip->ip_sum = 0; 1693 if (port == 0) 1694 ip->ip_p = IPPROTO_TCP; 1695 else 1696 ip->ip_p = IPPROTO_UDP; 1697 ip->ip_src = inp->inp_laddr; 1698 ip->ip_dst = inp->inp_faddr; 1699 } 1700 #endif /* INET */ 1701 th->th_sport = inp->inp_lport; 1702 th->th_dport = inp->inp_fport; 1703 th->th_seq = 0; 1704 th->th_ack = 0; 1705 th->th_x2 = 0; 1706 th->th_off = 5; 1707 th->th_flags = 0; 1708 th->th_win = 0; 1709 th->th_urp = 0; 1710 th->th_sum = 0; /* in_pseudo() is called later for ipv4 */ 1711 } 1712 1713 /* 1714 * Create template to be used to send tcp packets on a connection. 1715 * Allocates an mbuf and fills in a skeletal tcp/ip header. The only 1716 * use for this function is in keepalives, which use tcp_respond. 1717 */ 1718 struct tcptemp * 1719 tcpip_maketemplate(struct inpcb *inp) 1720 { 1721 struct tcptemp *t; 1722 1723 t = malloc(sizeof(*t), M_TEMP, M_NOWAIT); 1724 if (t == NULL) 1725 return (NULL); 1726 tcpip_fillheaders(inp, 0, (void *)&t->tt_ipgen, (void *)&t->tt_t); 1727 return (t); 1728 } 1729 1730 /* 1731 * Send a single message to the TCP at address specified by 1732 * the given TCP/IP header. If m == NULL, then we make a copy 1733 * of the tcpiphdr at th and send directly to the addressed host. 1734 * This is used to force keep alive messages out using the TCP 1735 * template for a connection. If flags are given then we send 1736 * a message back to the TCP which originated the segment th, 1737 * and discard the mbuf containing it and any other attached mbufs. 1738 * 1739 * In any case the ack and sequence number of the transmitted 1740 * segment are as specified by the parameters. 1741 * 1742 * NOTE: If m != NULL, then th must point to *inside* the mbuf. 1743 */ 1744 void 1745 tcp_respond(struct tcpcb *tp, void *ipgen, struct tcphdr *th, struct mbuf *m, 1746 tcp_seq ack, tcp_seq seq, int flags) 1747 { 1748 struct tcpopt to; 1749 struct inpcb *inp; 1750 struct ip *ip; 1751 struct mbuf *optm; 1752 struct udphdr *uh = NULL; 1753 struct tcphdr *nth; 1754 struct tcp_log_buffer *lgb; 1755 u_char *optp; 1756 #ifdef INET6 1757 struct ip6_hdr *ip6; 1758 int isipv6; 1759 #endif /* INET6 */ 1760 int optlen, tlen, win, ulen; 1761 bool incl_opts; 1762 uint16_t port; 1763 int output_ret; 1764 #ifdef INVARIANTS 1765 int thflags = th->th_flags; 1766 #endif 1767 1768 KASSERT(tp != NULL || m != NULL, ("tcp_respond: tp and m both NULL")); 1769 NET_EPOCH_ASSERT(); 1770 1771 #ifdef INET6 1772 isipv6 = ((struct ip *)ipgen)->ip_v == (IPV6_VERSION >> 4); 1773 ip6 = ipgen; 1774 #endif /* INET6 */ 1775 ip = ipgen; 1776 1777 if (tp != NULL) { 1778 inp = tp->t_inpcb; 1779 KASSERT(inp != NULL, ("tcp control block w/o inpcb")); 1780 INP_LOCK_ASSERT(inp); 1781 } else 1782 inp = NULL; 1783 1784 if (m != NULL) { 1785 #ifdef INET6 1786 if (isipv6 && ip6 && (ip6->ip6_nxt == IPPROTO_UDP)) 1787 port = m->m_pkthdr.tcp_tun_port; 1788 else 1789 #endif 1790 if (ip && (ip->ip_p == IPPROTO_UDP)) 1791 port = m->m_pkthdr.tcp_tun_port; 1792 else 1793 port = 0; 1794 } else 1795 port = tp->t_port; 1796 1797 incl_opts = false; 1798 win = 0; 1799 if (tp != NULL) { 1800 if (!(flags & TH_RST)) { 1801 win = sbspace(&inp->inp_socket->so_rcv); 1802 if (win > TCP_MAXWIN << tp->rcv_scale) 1803 win = TCP_MAXWIN << tp->rcv_scale; 1804 } 1805 if ((tp->t_flags & TF_NOOPT) == 0) 1806 incl_opts = true; 1807 } 1808 if (m == NULL) { 1809 m = m_gethdr(M_NOWAIT, MT_DATA); 1810 if (m == NULL) 1811 return; 1812 m->m_data += max_linkhdr; 1813 #ifdef INET6 1814 if (isipv6) { 1815 bcopy((caddr_t)ip6, mtod(m, caddr_t), 1816 sizeof(struct ip6_hdr)); 1817 ip6 = mtod(m, struct ip6_hdr *); 1818 nth = (struct tcphdr *)(ip6 + 1); 1819 if (port) { 1820 /* Insert a UDP header */ 1821 uh = (struct udphdr *)nth; 1822 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1823 uh->uh_dport = port; 1824 nth = (struct tcphdr *)(uh + 1); 1825 } 1826 } else 1827 #endif /* INET6 */ 1828 { 1829 bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip)); 1830 ip = mtod(m, struct ip *); 1831 nth = (struct tcphdr *)(ip + 1); 1832 if (port) { 1833 /* Insert a UDP header */ 1834 uh = (struct udphdr *)nth; 1835 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1836 uh->uh_dport = port; 1837 nth = (struct tcphdr *)(uh + 1); 1838 } 1839 } 1840 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr)); 1841 flags = TH_ACK; 1842 } else if ((!M_WRITABLE(m)) || (port != 0)) { 1843 struct mbuf *n; 1844 1845 /* Can't reuse 'm', allocate a new mbuf. */ 1846 n = m_gethdr(M_NOWAIT, MT_DATA); 1847 if (n == NULL) { 1848 m_freem(m); 1849 return; 1850 } 1851 1852 if (!m_dup_pkthdr(n, m, M_NOWAIT)) { 1853 m_freem(m); 1854 m_freem(n); 1855 return; 1856 } 1857 1858 n->m_data += max_linkhdr; 1859 /* m_len is set later */ 1860 #define xchg(a,b,type) { type t; t=a; a=b; b=t; } 1861 #ifdef INET6 1862 if (isipv6) { 1863 bcopy((caddr_t)ip6, mtod(n, caddr_t), 1864 sizeof(struct ip6_hdr)); 1865 ip6 = mtod(n, struct ip6_hdr *); 1866 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); 1867 nth = (struct tcphdr *)(ip6 + 1); 1868 if (port) { 1869 /* Insert a UDP header */ 1870 uh = (struct udphdr *)nth; 1871 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1872 uh->uh_dport = port; 1873 nth = (struct tcphdr *)(uh + 1); 1874 } 1875 } else 1876 #endif /* INET6 */ 1877 { 1878 bcopy((caddr_t)ip, mtod(n, caddr_t), sizeof(struct ip)); 1879 ip = mtod(n, struct ip *); 1880 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t); 1881 nth = (struct tcphdr *)(ip + 1); 1882 if (port) { 1883 /* Insert a UDP header */ 1884 uh = (struct udphdr *)nth; 1885 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1886 uh->uh_dport = port; 1887 nth = (struct tcphdr *)(uh + 1); 1888 } 1889 } 1890 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr)); 1891 xchg(nth->th_dport, nth->th_sport, uint16_t); 1892 th = nth; 1893 m_freem(m); 1894 m = n; 1895 } else { 1896 /* 1897 * reuse the mbuf. 1898 * XXX MRT We inherit the FIB, which is lucky. 1899 */ 1900 m_freem(m->m_next); 1901 m->m_next = NULL; 1902 m->m_data = (caddr_t)ipgen; 1903 /* m_len is set later */ 1904 #ifdef INET6 1905 if (isipv6) { 1906 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); 1907 nth = (struct tcphdr *)(ip6 + 1); 1908 } else 1909 #endif /* INET6 */ 1910 { 1911 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t); 1912 nth = (struct tcphdr *)(ip + 1); 1913 } 1914 if (th != nth) { 1915 /* 1916 * this is usually a case when an extension header 1917 * exists between the IPv6 header and the 1918 * TCP header. 1919 */ 1920 nth->th_sport = th->th_sport; 1921 nth->th_dport = th->th_dport; 1922 } 1923 xchg(nth->th_dport, nth->th_sport, uint16_t); 1924 #undef xchg 1925 } 1926 tlen = 0; 1927 #ifdef INET6 1928 if (isipv6) 1929 tlen = sizeof (struct ip6_hdr) + sizeof (struct tcphdr); 1930 #endif 1931 #if defined(INET) && defined(INET6) 1932 else 1933 #endif 1934 #ifdef INET 1935 tlen = sizeof (struct tcpiphdr); 1936 #endif 1937 if (port) 1938 tlen += sizeof (struct udphdr); 1939 #ifdef INVARIANTS 1940 m->m_len = 0; 1941 KASSERT(M_TRAILINGSPACE(m) >= tlen, 1942 ("Not enough trailing space for message (m=%p, need=%d, have=%ld)", 1943 m, tlen, (long)M_TRAILINGSPACE(m))); 1944 #endif 1945 m->m_len = tlen; 1946 to.to_flags = 0; 1947 if (incl_opts) { 1948 /* Make sure we have room. */ 1949 if (M_TRAILINGSPACE(m) < TCP_MAXOLEN) { 1950 m->m_next = m_get(M_NOWAIT, MT_DATA); 1951 if (m->m_next) { 1952 optp = mtod(m->m_next, u_char *); 1953 optm = m->m_next; 1954 } else 1955 incl_opts = false; 1956 } else { 1957 optp = (u_char *) (nth + 1); 1958 optm = m; 1959 } 1960 } 1961 if (incl_opts) { 1962 /* Timestamps. */ 1963 if (tp->t_flags & TF_RCVD_TSTMP) { 1964 to.to_tsval = tcp_ts_getticks() + tp->ts_offset; 1965 to.to_tsecr = tp->ts_recent; 1966 to.to_flags |= TOF_TS; 1967 } 1968 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 1969 /* TCP-MD5 (RFC2385). */ 1970 if (tp->t_flags & TF_SIGNATURE) 1971 to.to_flags |= TOF_SIGNATURE; 1972 #endif 1973 /* Add the options. */ 1974 tlen += optlen = tcp_addoptions(&to, optp); 1975 1976 /* Update m_len in the correct mbuf. */ 1977 optm->m_len += optlen; 1978 } else 1979 optlen = 0; 1980 #ifdef INET6 1981 if (isipv6) { 1982 if (uh) { 1983 ulen = tlen - sizeof(struct ip6_hdr); 1984 uh->uh_ulen = htons(ulen); 1985 } 1986 ip6->ip6_flow = 0; 1987 ip6->ip6_vfc = IPV6_VERSION; 1988 if (port) 1989 ip6->ip6_nxt = IPPROTO_UDP; 1990 else 1991 ip6->ip6_nxt = IPPROTO_TCP; 1992 ip6->ip6_plen = htons(tlen - sizeof(*ip6)); 1993 } 1994 #endif 1995 #if defined(INET) && defined(INET6) 1996 else 1997 #endif 1998 #ifdef INET 1999 { 2000 if (uh) { 2001 ulen = tlen - sizeof(struct ip); 2002 uh->uh_ulen = htons(ulen); 2003 } 2004 ip->ip_len = htons(tlen); 2005 ip->ip_ttl = V_ip_defttl; 2006 if (port) { 2007 ip->ip_p = IPPROTO_UDP; 2008 } else { 2009 ip->ip_p = IPPROTO_TCP; 2010 } 2011 if (V_path_mtu_discovery) 2012 ip->ip_off |= htons(IP_DF); 2013 } 2014 #endif 2015 m->m_pkthdr.len = tlen; 2016 m->m_pkthdr.rcvif = NULL; 2017 #ifdef MAC 2018 if (inp != NULL) { 2019 /* 2020 * Packet is associated with a socket, so allow the 2021 * label of the response to reflect the socket label. 2022 */ 2023 INP_LOCK_ASSERT(inp); 2024 mac_inpcb_create_mbuf(inp, m); 2025 } else { 2026 /* 2027 * Packet is not associated with a socket, so possibly 2028 * update the label in place. 2029 */ 2030 mac_netinet_tcp_reply(m); 2031 } 2032 #endif 2033 nth->th_seq = htonl(seq); 2034 nth->th_ack = htonl(ack); 2035 nth->th_x2 = 0; 2036 nth->th_off = (sizeof (struct tcphdr) + optlen) >> 2; 2037 nth->th_flags = flags; 2038 if (tp != NULL) 2039 nth->th_win = htons((u_short) (win >> tp->rcv_scale)); 2040 else 2041 nth->th_win = htons((u_short)win); 2042 nth->th_urp = 0; 2043 2044 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 2045 if (to.to_flags & TOF_SIGNATURE) { 2046 if (!TCPMD5_ENABLED() || 2047 TCPMD5_OUTPUT(m, nth, to.to_signature) != 0) { 2048 m_freem(m); 2049 return; 2050 } 2051 } 2052 #endif 2053 2054 #ifdef INET6 2055 if (isipv6) { 2056 if (port) { 2057 m->m_pkthdr.csum_flags = CSUM_UDP_IPV6; 2058 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 2059 uh->uh_sum = in6_cksum_pseudo(ip6, ulen, IPPROTO_UDP, 0); 2060 nth->th_sum = 0; 2061 } else { 2062 m->m_pkthdr.csum_flags = CSUM_TCP_IPV6; 2063 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); 2064 nth->th_sum = in6_cksum_pseudo(ip6, 2065 tlen - sizeof(struct ip6_hdr), IPPROTO_TCP, 0); 2066 } 2067 ip6->ip6_hlim = in6_selecthlim(tp != NULL ? tp->t_inpcb : 2068 NULL, NULL); 2069 } 2070 #endif /* INET6 */ 2071 #if defined(INET6) && defined(INET) 2072 else 2073 #endif 2074 #ifdef INET 2075 { 2076 if (port) { 2077 uh->uh_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, 2078 htons(ulen + IPPROTO_UDP)); 2079 m->m_pkthdr.csum_flags = CSUM_UDP; 2080 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 2081 nth->th_sum = 0; 2082 } else { 2083 m->m_pkthdr.csum_flags = CSUM_TCP; 2084 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); 2085 nth->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, 2086 htons((u_short)(tlen - sizeof(struct ip) + ip->ip_p))); 2087 } 2088 } 2089 #endif /* INET */ 2090 #ifdef TCPDEBUG 2091 if (tp == NULL || (inp->inp_socket->so_options & SO_DEBUG)) 2092 tcp_trace(TA_OUTPUT, 0, tp, mtod(m, void *), th, 0); 2093 #endif 2094 TCP_PROBE3(debug__output, tp, th, m); 2095 if (flags & TH_RST) 2096 TCP_PROBE5(accept__refused, NULL, NULL, m, tp, nth); 2097 lgb = NULL; 2098 if ((tp != NULL) && (tp->t_logstate != TCP_LOG_STATE_OFF)) { 2099 if (INP_WLOCKED(inp)) { 2100 union tcp_log_stackspecific log; 2101 struct timeval tv; 2102 2103 memset(&log.u_bbr, 0, sizeof(log.u_bbr)); 2104 log.u_bbr.inhpts = tp->t_inpcb->inp_in_hpts; 2105 log.u_bbr.ininput = tp->t_inpcb->inp_in_dropq; 2106 log.u_bbr.flex8 = 4; 2107 log.u_bbr.pkts_out = tp->t_maxseg; 2108 log.u_bbr.timeStamp = tcp_get_usecs(&tv); 2109 log.u_bbr.delivered = 0; 2110 lgb = tcp_log_event_(tp, nth, NULL, NULL, TCP_LOG_OUT, 2111 ERRNO_UNK, 0, &log, false, NULL, NULL, 0, &tv); 2112 } else { 2113 /* 2114 * We can not log the packet, since we only own the 2115 * read lock, but a write lock is needed. The read lock 2116 * is not upgraded to a write lock, since only getting 2117 * the read lock was done intentionally to improve the 2118 * handling of SYN flooding attacks. 2119 * This happens only for pure SYN segments received in 2120 * the initial CLOSED state, or received in a more 2121 * advanced state than listen and the UDP encapsulation 2122 * port is unexpected. 2123 * The incoming SYN segments do not really belong to 2124 * the TCP connection and the handling does not change 2125 * the state of the TCP connection. Therefore, the 2126 * sending of the RST segments is not logged. Please 2127 * note that also the incoming SYN segments are not 2128 * logged. 2129 * 2130 * The following code ensures that the above description 2131 * is and stays correct. 2132 */ 2133 KASSERT((thflags & (TH_ACK|TH_SYN)) == TH_SYN && 2134 (tp->t_state == TCPS_CLOSED || 2135 (tp->t_state > TCPS_LISTEN && tp->t_port != port)), 2136 ("%s: Logging of TCP segment with flags 0x%b and " 2137 "UDP encapsulation port %u skipped in state %s", 2138 __func__, thflags, PRINT_TH_FLAGS, 2139 ntohs(port), tcpstates[tp->t_state])); 2140 } 2141 } 2142 2143 #ifdef INET6 2144 if (isipv6) { 2145 TCP_PROBE5(send, NULL, tp, ip6, tp, nth); 2146 output_ret = ip6_output(m, NULL, NULL, 0, NULL, NULL, inp); 2147 } 2148 #endif /* INET6 */ 2149 #if defined(INET) && defined(INET6) 2150 else 2151 #endif 2152 #ifdef INET 2153 { 2154 TCP_PROBE5(send, NULL, tp, ip, tp, nth); 2155 output_ret = ip_output(m, NULL, NULL, 0, NULL, inp); 2156 } 2157 #endif 2158 if (lgb != NULL) 2159 lgb->tlb_errno = output_ret; 2160 } 2161 2162 /* 2163 * Create a new TCP control block, making an 2164 * empty reassembly queue and hooking it to the argument 2165 * protocol control block. The `inp' parameter must have 2166 * come from the zone allocator set up in tcp_init(). 2167 */ 2168 struct tcpcb * 2169 tcp_newtcpcb(struct inpcb *inp) 2170 { 2171 struct tcpcb_mem *tm; 2172 struct tcpcb *tp; 2173 #ifdef INET6 2174 int isipv6 = (inp->inp_vflag & INP_IPV6) != 0; 2175 #endif /* INET6 */ 2176 2177 tm = uma_zalloc(V_tcpcb_zone, M_NOWAIT | M_ZERO); 2178 if (tm == NULL) 2179 return (NULL); 2180 tp = &tm->tcb; 2181 2182 /* Initialise cc_var struct for this tcpcb. */ 2183 tp->ccv = &tm->ccv; 2184 tp->ccv->type = IPPROTO_TCP; 2185 tp->ccv->ccvc.tcp = tp; 2186 rw_rlock(&tcp_function_lock); 2187 tp->t_fb = tcp_func_set_ptr; 2188 refcount_acquire(&tp->t_fb->tfb_refcnt); 2189 rw_runlock(&tcp_function_lock); 2190 /* 2191 * Use the current system default CC algorithm. 2192 */ 2193 CC_LIST_RLOCK(); 2194 KASSERT(!STAILQ_EMPTY(&cc_list), ("cc_list is empty!")); 2195 CC_ALGO(tp) = CC_DEFAULT_ALGO(); 2196 CC_LIST_RUNLOCK(); 2197 2198 /* 2199 * The tcpcb will hold a reference on its inpcb until tcp_discardcb() 2200 * is called. 2201 */ 2202 in_pcbref(inp); /* Reference for tcpcb */ 2203 tp->t_inpcb = inp; 2204 2205 if (CC_ALGO(tp)->cb_init != NULL) 2206 if (CC_ALGO(tp)->cb_init(tp->ccv, NULL) > 0) { 2207 if (tp->t_fb->tfb_tcp_fb_fini) 2208 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); 2209 in_pcbrele_wlocked(inp); 2210 refcount_release(&tp->t_fb->tfb_refcnt); 2211 uma_zfree(V_tcpcb_zone, tm); 2212 return (NULL); 2213 } 2214 2215 #ifdef TCP_HHOOK 2216 tp->osd = &tm->osd; 2217 if (khelp_init_osd(HELPER_CLASS_TCP, tp->osd)) { 2218 if (tp->t_fb->tfb_tcp_fb_fini) 2219 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); 2220 in_pcbrele_wlocked(inp); 2221 refcount_release(&tp->t_fb->tfb_refcnt); 2222 uma_zfree(V_tcpcb_zone, tm); 2223 return (NULL); 2224 } 2225 #endif 2226 2227 #ifdef VIMAGE 2228 tp->t_vnet = inp->inp_vnet; 2229 #endif 2230 tp->t_timers = &tm->tt; 2231 TAILQ_INIT(&tp->t_segq); 2232 tp->t_maxseg = 2233 #ifdef INET6 2234 isipv6 ? V_tcp_v6mssdflt : 2235 #endif /* INET6 */ 2236 V_tcp_mssdflt; 2237 2238 /* Set up our timeouts. */ 2239 callout_init(&tp->t_timers->tt_rexmt, 1); 2240 callout_init(&tp->t_timers->tt_persist, 1); 2241 callout_init(&tp->t_timers->tt_keep, 1); 2242 callout_init(&tp->t_timers->tt_2msl, 1); 2243 callout_init(&tp->t_timers->tt_delack, 1); 2244 2245 if (V_tcp_do_rfc1323) 2246 tp->t_flags = (TF_REQ_SCALE|TF_REQ_TSTMP); 2247 if (V_tcp_do_sack) 2248 tp->t_flags |= TF_SACK_PERMIT; 2249 TAILQ_INIT(&tp->snd_holes); 2250 2251 /* 2252 * Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no 2253 * rtt estimate. Set rttvar so that srtt + 4 * rttvar gives 2254 * reasonable initial retransmit time. 2255 */ 2256 tp->t_srtt = TCPTV_SRTTBASE; 2257 tp->t_rttvar = ((tcp_rexmit_initial - TCPTV_SRTTBASE) << TCP_RTTVAR_SHIFT) / 4; 2258 tp->t_rttmin = tcp_rexmit_min; 2259 tp->t_rxtcur = tcp_rexmit_initial; 2260 tp->snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT; 2261 tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT; 2262 tp->t_rcvtime = ticks; 2263 /* 2264 * IPv4 TTL initialization is necessary for an IPv6 socket as well, 2265 * because the socket may be bound to an IPv6 wildcard address, 2266 * which may match an IPv4-mapped IPv6 address. 2267 */ 2268 inp->inp_ip_ttl = V_ip_defttl; 2269 inp->inp_ppcb = tp; 2270 #ifdef TCPPCAP 2271 /* 2272 * Init the TCP PCAP queues. 2273 */ 2274 tcp_pcap_tcpcb_init(tp); 2275 #endif 2276 #ifdef TCP_BLACKBOX 2277 /* Initialize the per-TCPCB log data. */ 2278 tcp_log_tcpcbinit(tp); 2279 #endif 2280 tp->t_pacing_rate = -1; 2281 if (tp->t_fb->tfb_tcp_fb_init) { 2282 if ((*tp->t_fb->tfb_tcp_fb_init)(tp)) { 2283 refcount_release(&tp->t_fb->tfb_refcnt); 2284 in_pcbrele_wlocked(inp); 2285 uma_zfree(V_tcpcb_zone, tm); 2286 return (NULL); 2287 } 2288 } 2289 #ifdef STATS 2290 if (V_tcp_perconn_stats_enable == 1) 2291 tp->t_stats = stats_blob_alloc(V_tcp_perconn_stats_dflt_tpl, 0); 2292 #endif 2293 if (V_tcp_do_lrd) 2294 tp->t_flags |= TF_LRD; 2295 return (tp); /* XXX */ 2296 } 2297 2298 /* 2299 * Switch the congestion control algorithm back to Vnet default for any active 2300 * control blocks using an algorithm which is about to go away. If the algorithm 2301 * has a cb_init function and it fails (no memory) then the operation fails and 2302 * the unload will not succeed. 2303 * 2304 */ 2305 int 2306 tcp_ccalgounload(struct cc_algo *unload_algo) 2307 { 2308 struct cc_algo *oldalgo, *newalgo; 2309 struct inpcb *inp; 2310 struct tcpcb *tp; 2311 VNET_ITERATOR_DECL(vnet_iter); 2312 2313 /* 2314 * Check all active control blocks across all network stacks and change 2315 * any that are using "unload_algo" back to its default. If "unload_algo" 2316 * requires cleanup code to be run, call it. 2317 */ 2318 VNET_LIST_RLOCK(); 2319 VNET_FOREACH(vnet_iter) { 2320 CURVNET_SET(vnet_iter); 2321 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, 2322 INPLOOKUP_WLOCKPCB); 2323 /* 2324 * XXXGL: would new accept(2)d connections use algo being 2325 * unloaded? 2326 */ 2327 newalgo = CC_DEFAULT_ALGO(); 2328 while ((inp = inp_next(&inpi)) != NULL) { 2329 /* Important to skip tcptw structs. */ 2330 if (!(inp->inp_flags & INP_TIMEWAIT) && 2331 (tp = intotcpcb(inp)) != NULL) { 2332 /* 2333 * By holding INP_WLOCK here, we are assured 2334 * that the connection is not currently 2335 * executing inside the CC module's functions. 2336 * We attempt to switch to the Vnets default, 2337 * if the init fails then we fail the whole 2338 * operation and the module unload will fail. 2339 */ 2340 if (CC_ALGO(tp) == unload_algo) { 2341 struct cc_var cc_mem; 2342 int err; 2343 2344 oldalgo = CC_ALGO(tp); 2345 memset(&cc_mem, 0, sizeof(cc_mem)); 2346 cc_mem.ccvc.tcp = tp; 2347 if (newalgo->cb_init == NULL) { 2348 /* 2349 * No init we can skip the 2350 * dance around a possible failure. 2351 */ 2352 CC_DATA(tp) = NULL; 2353 goto proceed; 2354 } 2355 err = (newalgo->cb_init)(&cc_mem, NULL); 2356 if (err) { 2357 /* 2358 * Presumably no memory the caller will 2359 * need to try again. 2360 */ 2361 INP_WUNLOCK(inp); 2362 CURVNET_RESTORE(); 2363 VNET_LIST_RUNLOCK(); 2364 return (err); 2365 } 2366 proceed: 2367 if (oldalgo->cb_destroy != NULL) 2368 oldalgo->cb_destroy(tp->ccv); 2369 CC_ALGO(tp) = newalgo; 2370 memcpy(tp->ccv, &cc_mem, sizeof(struct cc_var)); 2371 if (TCPS_HAVEESTABLISHED(tp->t_state) && 2372 (CC_ALGO(tp)->conn_init != NULL)) { 2373 /* Yep run the connection init for the new CC */ 2374 CC_ALGO(tp)->conn_init(tp->ccv); 2375 } 2376 } 2377 } 2378 } 2379 CURVNET_RESTORE(); 2380 } 2381 VNET_LIST_RUNLOCK(); 2382 return (0); 2383 } 2384 2385 /* 2386 * Drop a TCP connection, reporting 2387 * the specified error. If connection is synchronized, 2388 * then send a RST to peer. 2389 */ 2390 struct tcpcb * 2391 tcp_drop(struct tcpcb *tp, int errno) 2392 { 2393 struct socket *so = tp->t_inpcb->inp_socket; 2394 2395 NET_EPOCH_ASSERT(); 2396 INP_WLOCK_ASSERT(tp->t_inpcb); 2397 2398 if (TCPS_HAVERCVDSYN(tp->t_state)) { 2399 tcp_state_change(tp, TCPS_CLOSED); 2400 (void) tp->t_fb->tfb_tcp_output(tp); 2401 TCPSTAT_INC(tcps_drops); 2402 } else 2403 TCPSTAT_INC(tcps_conndrops); 2404 if (errno == ETIMEDOUT && tp->t_softerror) 2405 errno = tp->t_softerror; 2406 so->so_error = errno; 2407 return (tcp_close(tp)); 2408 } 2409 2410 void 2411 tcp_discardcb(struct tcpcb *tp) 2412 { 2413 struct inpcb *inp = tp->t_inpcb; 2414 2415 INP_WLOCK_ASSERT(inp); 2416 2417 /* 2418 * Make sure that all of our timers are stopped before we delete the 2419 * PCB. 2420 * 2421 * If stopping a timer fails, we schedule a discard function in same 2422 * callout, and the last discard function called will take care of 2423 * deleting the tcpcb. 2424 */ 2425 tp->t_timers->tt_draincnt = 0; 2426 tcp_timer_stop(tp, TT_REXMT); 2427 tcp_timer_stop(tp, TT_PERSIST); 2428 tcp_timer_stop(tp, TT_KEEP); 2429 tcp_timer_stop(tp, TT_2MSL); 2430 tcp_timer_stop(tp, TT_DELACK); 2431 if (tp->t_fb->tfb_tcp_timer_stop_all) { 2432 /* 2433 * Call the stop-all function of the methods, 2434 * this function should call the tcp_timer_stop() 2435 * method with each of the function specific timeouts. 2436 * That stop will be called via the tfb_tcp_timer_stop() 2437 * which should use the async drain function of the 2438 * callout system (see tcp_var.h). 2439 */ 2440 tp->t_fb->tfb_tcp_timer_stop_all(tp); 2441 } 2442 2443 /* free the reassembly queue, if any */ 2444 tcp_reass_flush(tp); 2445 2446 #ifdef TCP_OFFLOAD 2447 /* Disconnect offload device, if any. */ 2448 if (tp->t_flags & TF_TOE) 2449 tcp_offload_detach(tp); 2450 #endif 2451 2452 tcp_free_sackholes(tp); 2453 2454 #ifdef TCPPCAP 2455 /* Free the TCP PCAP queues. */ 2456 tcp_pcap_drain(&(tp->t_inpkts)); 2457 tcp_pcap_drain(&(tp->t_outpkts)); 2458 #endif 2459 2460 /* Allow the CC algorithm to clean up after itself. */ 2461 if (CC_ALGO(tp)->cb_destroy != NULL) 2462 CC_ALGO(tp)->cb_destroy(tp->ccv); 2463 CC_DATA(tp) = NULL; 2464 2465 #ifdef TCP_HHOOK 2466 khelp_destroy_osd(tp->osd); 2467 #endif 2468 #ifdef STATS 2469 stats_blob_destroy(tp->t_stats); 2470 #endif 2471 2472 CC_ALGO(tp) = NULL; 2473 inp->inp_ppcb = NULL; 2474 if (tp->t_timers->tt_draincnt == 0) { 2475 bool released __diagused; 2476 2477 released = tcp_freecb(tp); 2478 KASSERT(!released, ("%s: inp %p should not have been released " 2479 "here", __func__, inp)); 2480 } 2481 } 2482 2483 bool 2484 tcp_freecb(struct tcpcb *tp) 2485 { 2486 struct inpcb *inp = tp->t_inpcb; 2487 struct socket *so = inp->inp_socket; 2488 #ifdef INET6 2489 bool isipv6 = (inp->inp_vflag & INP_IPV6) != 0; 2490 #endif 2491 2492 INP_WLOCK_ASSERT(inp); 2493 MPASS(tp->t_timers->tt_draincnt == 0); 2494 2495 /* We own the last reference on tcpcb, let's free it. */ 2496 #ifdef TCP_BLACKBOX 2497 tcp_log_tcpcbfini(tp); 2498 #endif 2499 TCPSTATES_DEC(tp->t_state); 2500 if (tp->t_fb->tfb_tcp_fb_fini) 2501 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); 2502 2503 /* 2504 * If we got enough samples through the srtt filter, 2505 * save the rtt and rttvar in the routing entry. 2506 * 'Enough' is arbitrarily defined as 4 rtt samples. 2507 * 4 samples is enough for the srtt filter to converge 2508 * to within enough % of the correct value; fewer samples 2509 * and we could save a bogus rtt. The danger is not high 2510 * as tcp quickly recovers from everything. 2511 * XXX: Works very well but needs some more statistics! 2512 * 2513 * XXXRRS: Updating must be after the stack fini() since 2514 * that may be converting some internal representation of 2515 * say srtt etc into the general one used by other stacks. 2516 * Lets also at least protect against the so being NULL 2517 * as RW stated below. 2518 */ 2519 if ((tp->t_rttupdated >= 4) && (so != NULL)) { 2520 struct hc_metrics_lite metrics; 2521 uint32_t ssthresh; 2522 2523 bzero(&metrics, sizeof(metrics)); 2524 /* 2525 * Update the ssthresh always when the conditions below 2526 * are satisfied. This gives us better new start value 2527 * for the congestion avoidance for new connections. 2528 * ssthresh is only set if packet loss occurred on a session. 2529 * 2530 * XXXRW: 'so' may be NULL here, and/or socket buffer may be 2531 * being torn down. Ideally this code would not use 'so'. 2532 */ 2533 ssthresh = tp->snd_ssthresh; 2534 if (ssthresh != 0 && ssthresh < so->so_snd.sb_hiwat / 2) { 2535 /* 2536 * convert the limit from user data bytes to 2537 * packets then to packet data bytes. 2538 */ 2539 ssthresh = (ssthresh + tp->t_maxseg / 2) / tp->t_maxseg; 2540 if (ssthresh < 2) 2541 ssthresh = 2; 2542 ssthresh *= (tp->t_maxseg + 2543 #ifdef INET6 2544 (isipv6 ? sizeof (struct ip6_hdr) + 2545 sizeof (struct tcphdr) : 2546 #endif 2547 sizeof (struct tcpiphdr) 2548 #ifdef INET6 2549 ) 2550 #endif 2551 ); 2552 } else 2553 ssthresh = 0; 2554 metrics.rmx_ssthresh = ssthresh; 2555 2556 metrics.rmx_rtt = tp->t_srtt; 2557 metrics.rmx_rttvar = tp->t_rttvar; 2558 metrics.rmx_cwnd = tp->snd_cwnd; 2559 metrics.rmx_sendpipe = 0; 2560 metrics.rmx_recvpipe = 0; 2561 2562 tcp_hc_update(&inp->inp_inc, &metrics); 2563 } 2564 2565 refcount_release(&tp->t_fb->tfb_refcnt); 2566 uma_zfree(V_tcpcb_zone, tp); 2567 2568 return (in_pcbrele_wlocked(inp)); 2569 } 2570 2571 /* 2572 * Attempt to close a TCP control block, marking it as dropped, and freeing 2573 * the socket if we hold the only reference. 2574 */ 2575 struct tcpcb * 2576 tcp_close(struct tcpcb *tp) 2577 { 2578 struct inpcb *inp = tp->t_inpcb; 2579 struct socket *so; 2580 2581 INP_WLOCK_ASSERT(inp); 2582 2583 #ifdef TCP_OFFLOAD 2584 if (tp->t_state == TCPS_LISTEN) 2585 tcp_offload_listen_stop(tp); 2586 #endif 2587 /* 2588 * This releases the TFO pending counter resource for TFO listen 2589 * sockets as well as passively-created TFO sockets that transition 2590 * from SYN_RECEIVED to CLOSED. 2591 */ 2592 if (tp->t_tfo_pending) { 2593 tcp_fastopen_decrement_counter(tp->t_tfo_pending); 2594 tp->t_tfo_pending = NULL; 2595 } 2596 #ifdef TCPHPTS 2597 tcp_hpts_remove(inp, HPTS_REMOVE_ALL); 2598 #endif 2599 in_pcbdrop(inp); 2600 TCPSTAT_INC(tcps_closed); 2601 if (tp->t_state != TCPS_CLOSED) 2602 tcp_state_change(tp, TCPS_CLOSED); 2603 KASSERT(inp->inp_socket != NULL, ("tcp_close: inp_socket NULL")); 2604 so = inp->inp_socket; 2605 soisdisconnected(so); 2606 if (inp->inp_flags & INP_SOCKREF) { 2607 KASSERT(so->so_state & SS_PROTOREF, 2608 ("tcp_close: !SS_PROTOREF")); 2609 inp->inp_flags &= ~INP_SOCKREF; 2610 INP_WUNLOCK(inp); 2611 SOCK_LOCK(so); 2612 so->so_state &= ~SS_PROTOREF; 2613 sofree(so); 2614 return (NULL); 2615 } 2616 return (tp); 2617 } 2618 2619 void 2620 tcp_drain(void) 2621 { 2622 VNET_ITERATOR_DECL(vnet_iter); 2623 2624 if (!do_tcpdrain) 2625 return; 2626 2627 VNET_LIST_RLOCK_NOSLEEP(); 2628 VNET_FOREACH(vnet_iter) { 2629 CURVNET_SET(vnet_iter); 2630 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, 2631 INPLOOKUP_WLOCKPCB); 2632 struct inpcb *inpb; 2633 struct tcpcb *tcpb; 2634 2635 /* 2636 * Walk the tcpbs, if existing, and flush the reassembly queue, 2637 * if there is one... 2638 * XXX: The "Net/3" implementation doesn't imply that the TCP 2639 * reassembly queue should be flushed, but in a situation 2640 * where we're really low on mbufs, this is potentially 2641 * useful. 2642 */ 2643 while ((inpb = inp_next(&inpi)) != NULL) { 2644 if (inpb->inp_flags & INP_TIMEWAIT) 2645 continue; 2646 if ((tcpb = intotcpcb(inpb)) != NULL) { 2647 tcp_reass_flush(tcpb); 2648 tcp_clean_sackreport(tcpb); 2649 #ifdef TCP_BLACKBOX 2650 tcp_log_drain(tcpb); 2651 #endif 2652 #ifdef TCPPCAP 2653 if (tcp_pcap_aggressive_free) { 2654 /* Free the TCP PCAP queues. */ 2655 tcp_pcap_drain(&(tcpb->t_inpkts)); 2656 tcp_pcap_drain(&(tcpb->t_outpkts)); 2657 } 2658 #endif 2659 } 2660 } 2661 CURVNET_RESTORE(); 2662 } 2663 VNET_LIST_RUNLOCK_NOSLEEP(); 2664 } 2665 2666 /* 2667 * Notify a tcp user of an asynchronous error; 2668 * store error as soft error, but wake up user 2669 * (for now, won't do anything until can select for soft error). 2670 * 2671 * Do not wake up user since there currently is no mechanism for 2672 * reporting soft errors (yet - a kqueue filter may be added). 2673 */ 2674 static struct inpcb * 2675 tcp_notify(struct inpcb *inp, int error) 2676 { 2677 struct tcpcb *tp; 2678 2679 INP_WLOCK_ASSERT(inp); 2680 2681 if ((inp->inp_flags & INP_TIMEWAIT) || 2682 (inp->inp_flags & INP_DROPPED)) 2683 return (inp); 2684 2685 tp = intotcpcb(inp); 2686 KASSERT(tp != NULL, ("tcp_notify: tp == NULL")); 2687 2688 /* 2689 * Ignore some errors if we are hooked up. 2690 * If connection hasn't completed, has retransmitted several times, 2691 * and receives a second error, give up now. This is better 2692 * than waiting a long time to establish a connection that 2693 * can never complete. 2694 */ 2695 if (tp->t_state == TCPS_ESTABLISHED && 2696 (error == EHOSTUNREACH || error == ENETUNREACH || 2697 error == EHOSTDOWN)) { 2698 if (inp->inp_route.ro_nh) { 2699 NH_FREE(inp->inp_route.ro_nh); 2700 inp->inp_route.ro_nh = (struct nhop_object *)NULL; 2701 } 2702 return (inp); 2703 } else if (tp->t_state < TCPS_ESTABLISHED && tp->t_rxtshift > 3 && 2704 tp->t_softerror) { 2705 tp = tcp_drop(tp, error); 2706 if (tp != NULL) 2707 return (inp); 2708 else 2709 return (NULL); 2710 } else { 2711 tp->t_softerror = error; 2712 return (inp); 2713 } 2714 #if 0 2715 wakeup( &so->so_timeo); 2716 sorwakeup(so); 2717 sowwakeup(so); 2718 #endif 2719 } 2720 2721 static int 2722 tcp_pcblist(SYSCTL_HANDLER_ARGS) 2723 { 2724 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, 2725 INPLOOKUP_RLOCKPCB); 2726 struct xinpgen xig; 2727 struct inpcb *inp; 2728 int error; 2729 2730 if (req->newptr != NULL) 2731 return (EPERM); 2732 2733 if (req->oldptr == NULL) { 2734 int n; 2735 2736 n = V_tcbinfo.ipi_count + 2737 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); 2738 n += imax(n / 8, 10); 2739 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xtcpcb); 2740 return (0); 2741 } 2742 2743 if ((error = sysctl_wire_old_buffer(req, 0)) != 0) 2744 return (error); 2745 2746 bzero(&xig, sizeof(xig)); 2747 xig.xig_len = sizeof xig; 2748 xig.xig_count = V_tcbinfo.ipi_count + 2749 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); 2750 xig.xig_gen = V_tcbinfo.ipi_gencnt; 2751 xig.xig_sogen = so_gencnt; 2752 error = SYSCTL_OUT(req, &xig, sizeof xig); 2753 if (error) 2754 return (error); 2755 2756 error = syncache_pcblist(req); 2757 if (error) 2758 return (error); 2759 2760 while ((inp = inp_next(&inpi)) != NULL) { 2761 if (inp->inp_gencnt <= xig.xig_gen) { 2762 int crerr; 2763 2764 /* 2765 * XXX: This use of cr_cansee(), introduced with 2766 * TCP state changes, is not quite right, but for 2767 * now, better than nothing. 2768 */ 2769 if (inp->inp_flags & INP_TIMEWAIT) { 2770 if (intotw(inp) != NULL) 2771 crerr = cr_cansee(req->td->td_ucred, 2772 intotw(inp)->tw_cred); 2773 else 2774 crerr = EINVAL; /* Skip this inp. */ 2775 } else 2776 crerr = cr_canseeinpcb(req->td->td_ucred, inp); 2777 if (crerr == 0) { 2778 struct xtcpcb xt; 2779 2780 tcp_inptoxtp(inp, &xt); 2781 error = SYSCTL_OUT(req, &xt, sizeof xt); 2782 if (error) { 2783 INP_RUNLOCK(inp); 2784 break; 2785 } else 2786 continue; 2787 } 2788 } 2789 } 2790 2791 if (!error) { 2792 /* 2793 * Give the user an updated idea of our state. 2794 * If the generation differs from what we told 2795 * her before, she knows that something happened 2796 * while we were processing this request, and it 2797 * might be necessary to retry. 2798 */ 2799 xig.xig_gen = V_tcbinfo.ipi_gencnt; 2800 xig.xig_sogen = so_gencnt; 2801 xig.xig_count = V_tcbinfo.ipi_count + 2802 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); 2803 error = SYSCTL_OUT(req, &xig, sizeof xig); 2804 } 2805 2806 return (error); 2807 } 2808 2809 SYSCTL_PROC(_net_inet_tcp, TCPCTL_PCBLIST, pcblist, 2810 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_NEEDGIANT, 2811 NULL, 0, tcp_pcblist, "S,xtcpcb", 2812 "List of active TCP connections"); 2813 2814 #ifdef INET 2815 static int 2816 tcp_getcred(SYSCTL_HANDLER_ARGS) 2817 { 2818 struct xucred xuc; 2819 struct sockaddr_in addrs[2]; 2820 struct epoch_tracker et; 2821 struct inpcb *inp; 2822 int error; 2823 2824 error = priv_check(req->td, PRIV_NETINET_GETCRED); 2825 if (error) 2826 return (error); 2827 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 2828 if (error) 2829 return (error); 2830 NET_EPOCH_ENTER(et); 2831 inp = in_pcblookup(&V_tcbinfo, addrs[1].sin_addr, addrs[1].sin_port, 2832 addrs[0].sin_addr, addrs[0].sin_port, INPLOOKUP_RLOCKPCB, NULL); 2833 NET_EPOCH_EXIT(et); 2834 if (inp != NULL) { 2835 if (inp->inp_socket == NULL) 2836 error = ENOENT; 2837 if (error == 0) 2838 error = cr_canseeinpcb(req->td->td_ucred, inp); 2839 if (error == 0) 2840 cru2x(inp->inp_cred, &xuc); 2841 INP_RUNLOCK(inp); 2842 } else 2843 error = ENOENT; 2844 if (error == 0) 2845 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 2846 return (error); 2847 } 2848 2849 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, getcred, 2850 CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_NEEDGIANT, 2851 0, 0, tcp_getcred, "S,xucred", 2852 "Get the xucred of a TCP connection"); 2853 #endif /* INET */ 2854 2855 #ifdef INET6 2856 static int 2857 tcp6_getcred(SYSCTL_HANDLER_ARGS) 2858 { 2859 struct epoch_tracker et; 2860 struct xucred xuc; 2861 struct sockaddr_in6 addrs[2]; 2862 struct inpcb *inp; 2863 int error; 2864 #ifdef INET 2865 int mapped = 0; 2866 #endif 2867 2868 error = priv_check(req->td, PRIV_NETINET_GETCRED); 2869 if (error) 2870 return (error); 2871 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 2872 if (error) 2873 return (error); 2874 if ((error = sa6_embedscope(&addrs[0], V_ip6_use_defzone)) != 0 || 2875 (error = sa6_embedscope(&addrs[1], V_ip6_use_defzone)) != 0) { 2876 return (error); 2877 } 2878 if (IN6_IS_ADDR_V4MAPPED(&addrs[0].sin6_addr)) { 2879 #ifdef INET 2880 if (IN6_IS_ADDR_V4MAPPED(&addrs[1].sin6_addr)) 2881 mapped = 1; 2882 else 2883 #endif 2884 return (EINVAL); 2885 } 2886 2887 NET_EPOCH_ENTER(et); 2888 #ifdef INET 2889 if (mapped == 1) 2890 inp = in_pcblookup(&V_tcbinfo, 2891 *(struct in_addr *)&addrs[1].sin6_addr.s6_addr[12], 2892 addrs[1].sin6_port, 2893 *(struct in_addr *)&addrs[0].sin6_addr.s6_addr[12], 2894 addrs[0].sin6_port, INPLOOKUP_RLOCKPCB, NULL); 2895 else 2896 #endif 2897 inp = in6_pcblookup(&V_tcbinfo, 2898 &addrs[1].sin6_addr, addrs[1].sin6_port, 2899 &addrs[0].sin6_addr, addrs[0].sin6_port, 2900 INPLOOKUP_RLOCKPCB, NULL); 2901 NET_EPOCH_EXIT(et); 2902 if (inp != NULL) { 2903 if (inp->inp_socket == NULL) 2904 error = ENOENT; 2905 if (error == 0) 2906 error = cr_canseeinpcb(req->td->td_ucred, inp); 2907 if (error == 0) 2908 cru2x(inp->inp_cred, &xuc); 2909 INP_RUNLOCK(inp); 2910 } else 2911 error = ENOENT; 2912 if (error == 0) 2913 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 2914 return (error); 2915 } 2916 2917 SYSCTL_PROC(_net_inet6_tcp6, OID_AUTO, getcred, 2918 CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_NEEDGIANT, 2919 0, 0, tcp6_getcred, "S,xucred", 2920 "Get the xucred of a TCP6 connection"); 2921 #endif /* INET6 */ 2922 2923 #ifdef INET 2924 /* Path MTU to try next when a fragmentation-needed message is received. */ 2925 static inline int 2926 tcp_next_pmtu(const struct icmp *icp, const struct ip *ip) 2927 { 2928 int mtu = ntohs(icp->icmp_nextmtu); 2929 2930 /* If no alternative MTU was proposed, try the next smaller one. */ 2931 if (!mtu) 2932 mtu = ip_next_mtu(ntohs(ip->ip_len), 1); 2933 if (mtu < V_tcp_minmss + sizeof(struct tcpiphdr)) 2934 mtu = V_tcp_minmss + sizeof(struct tcpiphdr); 2935 2936 return (mtu); 2937 } 2938 2939 static void 2940 tcp_ctlinput_with_port(int cmd, struct sockaddr *sa, void *vip, uint16_t port) 2941 { 2942 struct ip *ip = vip; 2943 struct tcphdr *th; 2944 struct in_addr faddr; 2945 struct inpcb *inp; 2946 struct tcpcb *tp; 2947 struct inpcb *(*notify)(struct inpcb *, int) = tcp_notify; 2948 struct icmp *icp; 2949 struct in_conninfo inc; 2950 tcp_seq icmp_tcp_seq; 2951 int mtu; 2952 2953 faddr = ((struct sockaddr_in *)sa)->sin_addr; 2954 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY) 2955 return; 2956 2957 if (cmd == PRC_MSGSIZE) 2958 notify = tcp_mtudisc_notify; 2959 else if (V_icmp_may_rst && (cmd == PRC_UNREACH_ADMIN_PROHIB || 2960 cmd == PRC_UNREACH_PORT || cmd == PRC_UNREACH_PROTOCOL || 2961 cmd == PRC_TIMXCEED_INTRANS) && ip) 2962 notify = tcp_drop_syn_sent; 2963 2964 /* 2965 * Hostdead is ugly because it goes linearly through all PCBs. 2966 * XXX: We never get this from ICMP, otherwise it makes an 2967 * excellent DoS attack on machines with many connections. 2968 */ 2969 else if (cmd == PRC_HOSTDEAD) 2970 ip = NULL; 2971 else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0) 2972 return; 2973 2974 if (ip == NULL) { 2975 in_pcbnotifyall(&V_tcbinfo, faddr, inetctlerrmap[cmd], notify); 2976 return; 2977 } 2978 2979 icp = (struct icmp *)((caddr_t)ip - offsetof(struct icmp, icmp_ip)); 2980 th = (struct tcphdr *)((caddr_t)ip + (ip->ip_hl << 2)); 2981 inp = in_pcblookup(&V_tcbinfo, faddr, th->th_dport, ip->ip_src, 2982 th->th_sport, INPLOOKUP_WLOCKPCB, NULL); 2983 if (inp != NULL && PRC_IS_REDIRECT(cmd)) { 2984 /* signal EHOSTDOWN, as it flushes the cached route */ 2985 inp = (*notify)(inp, EHOSTDOWN); 2986 goto out; 2987 } 2988 icmp_tcp_seq = th->th_seq; 2989 if (inp != NULL) { 2990 if (!(inp->inp_flags & INP_TIMEWAIT) && 2991 !(inp->inp_flags & INP_DROPPED) && 2992 !(inp->inp_socket == NULL)) { 2993 tp = intotcpcb(inp); 2994 #ifdef TCP_OFFLOAD 2995 if (tp->t_flags & TF_TOE && cmd == PRC_MSGSIZE) { 2996 /* 2997 * MTU discovery for offloaded connections. Let 2998 * the TOE driver verify seq# and process it. 2999 */ 3000 mtu = tcp_next_pmtu(icp, ip); 3001 tcp_offload_pmtu_update(tp, icmp_tcp_seq, mtu); 3002 goto out; 3003 } 3004 #endif 3005 if (tp->t_port != port) { 3006 goto out; 3007 } 3008 if (SEQ_GEQ(ntohl(icmp_tcp_seq), tp->snd_una) && 3009 SEQ_LT(ntohl(icmp_tcp_seq), tp->snd_max)) { 3010 if (cmd == PRC_MSGSIZE) { 3011 /* 3012 * MTU discovery: we got a needfrag and 3013 * will potentially try a lower MTU. 3014 */ 3015 mtu = tcp_next_pmtu(icp, ip); 3016 3017 /* 3018 * Only process the offered MTU if it 3019 * is smaller than the current one. 3020 */ 3021 if (mtu < tp->t_maxseg + 3022 sizeof(struct tcpiphdr)) { 3023 bzero(&inc, sizeof(inc)); 3024 inc.inc_faddr = faddr; 3025 inc.inc_fibnum = 3026 inp->inp_inc.inc_fibnum; 3027 tcp_hc_updatemtu(&inc, mtu); 3028 tcp_mtudisc(inp, mtu); 3029 } 3030 } else 3031 inp = (*notify)(inp, 3032 inetctlerrmap[cmd]); 3033 } 3034 } 3035 } else { 3036 bzero(&inc, sizeof(inc)); 3037 inc.inc_fport = th->th_dport; 3038 inc.inc_lport = th->th_sport; 3039 inc.inc_faddr = faddr; 3040 inc.inc_laddr = ip->ip_src; 3041 syncache_unreach(&inc, icmp_tcp_seq, port); 3042 } 3043 out: 3044 if (inp != NULL) 3045 INP_WUNLOCK(inp); 3046 } 3047 3048 void 3049 tcp_ctlinput(int cmd, struct sockaddr *sa, void *vip) 3050 { 3051 tcp_ctlinput_with_port(cmd, sa, vip, htons(0)); 3052 } 3053 3054 void 3055 tcp_ctlinput_viaudp(int cmd, struct sockaddr *sa, void *vip, void *unused) 3056 { 3057 /* Its a tunneled TCP over UDP icmp */ 3058 struct ip *outer_ip, *inner_ip; 3059 struct icmp *icmp; 3060 struct udphdr *udp; 3061 struct tcphdr *th, ttemp; 3062 int i_hlen, o_len; 3063 uint16_t port; 3064 3065 inner_ip = (struct ip *)vip; 3066 icmp = (struct icmp *)((caddr_t)inner_ip - 3067 (sizeof(struct icmp) - sizeof(struct ip))); 3068 outer_ip = (struct ip *)((caddr_t)icmp - sizeof(struct ip)); 3069 i_hlen = inner_ip->ip_hl << 2; 3070 o_len = ntohs(outer_ip->ip_len); 3071 if (o_len < 3072 (sizeof(struct ip) + 8 + i_hlen + sizeof(struct udphdr) + offsetof(struct tcphdr, th_ack))) { 3073 /* Not enough data present */ 3074 return; 3075 } 3076 /* Ok lets strip out the inner udphdr header by copying up on top of it the tcp hdr */ 3077 udp = (struct udphdr *)(((caddr_t)inner_ip) + i_hlen); 3078 if (ntohs(udp->uh_sport) != V_tcp_udp_tunneling_port) { 3079 return; 3080 } 3081 port = udp->uh_dport; 3082 th = (struct tcphdr *)(udp + 1); 3083 memcpy(&ttemp, th, sizeof(struct tcphdr)); 3084 memcpy(udp, &ttemp, sizeof(struct tcphdr)); 3085 /* Now adjust down the size of the outer IP header */ 3086 o_len -= sizeof(struct udphdr); 3087 outer_ip->ip_len = htons(o_len); 3088 /* Now call in to the normal handling code */ 3089 tcp_ctlinput_with_port(cmd, sa, vip, port); 3090 } 3091 #endif /* INET */ 3092 3093 #ifdef INET6 3094 static inline int 3095 tcp6_next_pmtu(const struct icmp6_hdr *icmp6) 3096 { 3097 int mtu = ntohl(icmp6->icmp6_mtu); 3098 3099 /* 3100 * If no alternative MTU was proposed, or the proposed MTU was too 3101 * small, set to the min. 3102 */ 3103 if (mtu < IPV6_MMTU) 3104 mtu = IPV6_MMTU - 8; /* XXXNP: what is the adjustment for? */ 3105 return (mtu); 3106 } 3107 3108 static void 3109 tcp6_ctlinput_with_port(int cmd, struct sockaddr *sa, void *d, uint16_t port) 3110 { 3111 struct in6_addr *dst; 3112 struct inpcb *(*notify)(struct inpcb *, int) = tcp_notify; 3113 struct ip6_hdr *ip6; 3114 struct mbuf *m; 3115 struct inpcb *inp; 3116 struct tcpcb *tp; 3117 struct icmp6_hdr *icmp6; 3118 struct ip6ctlparam *ip6cp = NULL; 3119 const struct sockaddr_in6 *sa6_src = NULL; 3120 struct in_conninfo inc; 3121 struct tcp_ports { 3122 uint16_t th_sport; 3123 uint16_t th_dport; 3124 } t_ports; 3125 tcp_seq icmp_tcp_seq; 3126 unsigned int mtu; 3127 unsigned int off; 3128 3129 if (sa->sa_family != AF_INET6 || 3130 sa->sa_len != sizeof(struct sockaddr_in6)) 3131 return; 3132 3133 /* if the parameter is from icmp6, decode it. */ 3134 if (d != NULL) { 3135 ip6cp = (struct ip6ctlparam *)d; 3136 icmp6 = ip6cp->ip6c_icmp6; 3137 m = ip6cp->ip6c_m; 3138 ip6 = ip6cp->ip6c_ip6; 3139 off = ip6cp->ip6c_off; 3140 sa6_src = ip6cp->ip6c_src; 3141 dst = ip6cp->ip6c_finaldst; 3142 } else { 3143 m = NULL; 3144 ip6 = NULL; 3145 off = 0; /* fool gcc */ 3146 sa6_src = &sa6_any; 3147 dst = NULL; 3148 } 3149 3150 if (cmd == PRC_MSGSIZE) 3151 notify = tcp_mtudisc_notify; 3152 else if (V_icmp_may_rst && (cmd == PRC_UNREACH_ADMIN_PROHIB || 3153 cmd == PRC_UNREACH_PORT || cmd == PRC_UNREACH_PROTOCOL || 3154 cmd == PRC_TIMXCEED_INTRANS) && ip6 != NULL) 3155 notify = tcp_drop_syn_sent; 3156 3157 /* 3158 * Hostdead is ugly because it goes linearly through all PCBs. 3159 * XXX: We never get this from ICMP, otherwise it makes an 3160 * excellent DoS attack on machines with many connections. 3161 */ 3162 else if (cmd == PRC_HOSTDEAD) 3163 ip6 = NULL; 3164 else if ((unsigned)cmd >= PRC_NCMDS || inet6ctlerrmap[cmd] == 0) 3165 return; 3166 3167 if (ip6 == NULL) { 3168 in6_pcbnotify(&V_tcbinfo, sa, 0, 3169 (const struct sockaddr *)sa6_src, 3170 0, cmd, NULL, notify); 3171 return; 3172 } 3173 3174 /* Check if we can safely get the ports from the tcp hdr */ 3175 if (m == NULL || 3176 (m->m_pkthdr.len < 3177 (int32_t) (off + sizeof(struct tcp_ports)))) { 3178 return; 3179 } 3180 bzero(&t_ports, sizeof(struct tcp_ports)); 3181 m_copydata(m, off, sizeof(struct tcp_ports), (caddr_t)&t_ports); 3182 inp = in6_pcblookup(&V_tcbinfo, &ip6->ip6_dst, t_ports.th_dport, 3183 &ip6->ip6_src, t_ports.th_sport, INPLOOKUP_WLOCKPCB, NULL); 3184 if (inp != NULL && PRC_IS_REDIRECT(cmd)) { 3185 /* signal EHOSTDOWN, as it flushes the cached route */ 3186 inp = (*notify)(inp, EHOSTDOWN); 3187 goto out; 3188 } 3189 off += sizeof(struct tcp_ports); 3190 if (m->m_pkthdr.len < (int32_t) (off + sizeof(tcp_seq))) { 3191 goto out; 3192 } 3193 m_copydata(m, off, sizeof(tcp_seq), (caddr_t)&icmp_tcp_seq); 3194 if (inp != NULL) { 3195 if (!(inp->inp_flags & INP_TIMEWAIT) && 3196 !(inp->inp_flags & INP_DROPPED) && 3197 !(inp->inp_socket == NULL)) { 3198 tp = intotcpcb(inp); 3199 #ifdef TCP_OFFLOAD 3200 if (tp->t_flags & TF_TOE && cmd == PRC_MSGSIZE) { 3201 /* MTU discovery for offloaded connections. */ 3202 mtu = tcp6_next_pmtu(icmp6); 3203 tcp_offload_pmtu_update(tp, icmp_tcp_seq, mtu); 3204 goto out; 3205 } 3206 #endif 3207 if (tp->t_port != port) { 3208 goto out; 3209 } 3210 if (SEQ_GEQ(ntohl(icmp_tcp_seq), tp->snd_una) && 3211 SEQ_LT(ntohl(icmp_tcp_seq), tp->snd_max)) { 3212 if (cmd == PRC_MSGSIZE) { 3213 /* 3214 * MTU discovery: 3215 * If we got a needfrag set the MTU 3216 * in the route to the suggested new 3217 * value (if given) and then notify. 3218 */ 3219 mtu = tcp6_next_pmtu(icmp6); 3220 3221 bzero(&inc, sizeof(inc)); 3222 inc.inc_fibnum = M_GETFIB(m); 3223 inc.inc_flags |= INC_ISIPV6; 3224 inc.inc6_faddr = *dst; 3225 if (in6_setscope(&inc.inc6_faddr, 3226 m->m_pkthdr.rcvif, NULL)) 3227 goto out; 3228 /* 3229 * Only process the offered MTU if it 3230 * is smaller than the current one. 3231 */ 3232 if (mtu < tp->t_maxseg + 3233 sizeof (struct tcphdr) + 3234 sizeof (struct ip6_hdr)) { 3235 tcp_hc_updatemtu(&inc, mtu); 3236 tcp_mtudisc(inp, mtu); 3237 ICMP6STAT_INC(icp6s_pmtuchg); 3238 } 3239 } else 3240 inp = (*notify)(inp, 3241 inet6ctlerrmap[cmd]); 3242 } 3243 } 3244 } else { 3245 bzero(&inc, sizeof(inc)); 3246 inc.inc_fibnum = M_GETFIB(m); 3247 inc.inc_flags |= INC_ISIPV6; 3248 inc.inc_fport = t_ports.th_dport; 3249 inc.inc_lport = t_ports.th_sport; 3250 inc.inc6_faddr = *dst; 3251 inc.inc6_laddr = ip6->ip6_src; 3252 syncache_unreach(&inc, icmp_tcp_seq, port); 3253 } 3254 out: 3255 if (inp != NULL) 3256 INP_WUNLOCK(inp); 3257 } 3258 3259 void 3260 tcp6_ctlinput(int cmd, struct sockaddr *sa, void *d) 3261 { 3262 tcp6_ctlinput_with_port(cmd, sa, d, htons(0)); 3263 } 3264 3265 void 3266 tcp6_ctlinput_viaudp(int cmd, struct sockaddr *sa, void *d, void *unused) 3267 { 3268 struct ip6ctlparam *ip6cp; 3269 struct mbuf *m; 3270 struct udphdr *udp; 3271 uint16_t port; 3272 3273 ip6cp = (struct ip6ctlparam *)d; 3274 m = m_pulldown(ip6cp->ip6c_m, ip6cp->ip6c_off, sizeof(struct udphdr), NULL); 3275 if (m == NULL) { 3276 return; 3277 } 3278 udp = mtod(m, struct udphdr *); 3279 if (ntohs(udp->uh_sport) != V_tcp_udp_tunneling_port) { 3280 return; 3281 } 3282 port = udp->uh_dport; 3283 m_adj(m, sizeof(struct udphdr)); 3284 if ((m->m_flags & M_PKTHDR) == 0) { 3285 ip6cp->ip6c_m->m_pkthdr.len -= sizeof(struct udphdr); 3286 } 3287 /* Now call in to the normal handling code */ 3288 tcp6_ctlinput_with_port(cmd, sa, d, port); 3289 } 3290 3291 #endif /* INET6 */ 3292 3293 static uint32_t 3294 tcp_keyed_hash(struct in_conninfo *inc, u_char *key, u_int len) 3295 { 3296 SIPHASH_CTX ctx; 3297 uint32_t hash[2]; 3298 3299 KASSERT(len >= SIPHASH_KEY_LENGTH, 3300 ("%s: keylen %u too short ", __func__, len)); 3301 SipHash24_Init(&ctx); 3302 SipHash_SetKey(&ctx, (uint8_t *)key); 3303 SipHash_Update(&ctx, &inc->inc_fport, sizeof(uint16_t)); 3304 SipHash_Update(&ctx, &inc->inc_lport, sizeof(uint16_t)); 3305 switch (inc->inc_flags & INC_ISIPV6) { 3306 #ifdef INET 3307 case 0: 3308 SipHash_Update(&ctx, &inc->inc_faddr, sizeof(struct in_addr)); 3309 SipHash_Update(&ctx, &inc->inc_laddr, sizeof(struct in_addr)); 3310 break; 3311 #endif 3312 #ifdef INET6 3313 case INC_ISIPV6: 3314 SipHash_Update(&ctx, &inc->inc6_faddr, sizeof(struct in6_addr)); 3315 SipHash_Update(&ctx, &inc->inc6_laddr, sizeof(struct in6_addr)); 3316 break; 3317 #endif 3318 } 3319 SipHash_Final((uint8_t *)hash, &ctx); 3320 3321 return (hash[0] ^ hash[1]); 3322 } 3323 3324 uint32_t 3325 tcp_new_ts_offset(struct in_conninfo *inc) 3326 { 3327 struct in_conninfo inc_store, *local_inc; 3328 3329 if (!V_tcp_ts_offset_per_conn) { 3330 memcpy(&inc_store, inc, sizeof(struct in_conninfo)); 3331 inc_store.inc_lport = 0; 3332 inc_store.inc_fport = 0; 3333 local_inc = &inc_store; 3334 } else { 3335 local_inc = inc; 3336 } 3337 return (tcp_keyed_hash(local_inc, V_ts_offset_secret, 3338 sizeof(V_ts_offset_secret))); 3339 } 3340 3341 /* 3342 * Following is where TCP initial sequence number generation occurs. 3343 * 3344 * There are two places where we must use initial sequence numbers: 3345 * 1. In SYN-ACK packets. 3346 * 2. In SYN packets. 3347 * 3348 * All ISNs for SYN-ACK packets are generated by the syncache. See 3349 * tcp_syncache.c for details. 3350 * 3351 * The ISNs in SYN packets must be monotonic; TIME_WAIT recycling 3352 * depends on this property. In addition, these ISNs should be 3353 * unguessable so as to prevent connection hijacking. To satisfy 3354 * the requirements of this situation, the algorithm outlined in 3355 * RFC 1948 is used, with only small modifications. 3356 * 3357 * Implementation details: 3358 * 3359 * Time is based off the system timer, and is corrected so that it 3360 * increases by one megabyte per second. This allows for proper 3361 * recycling on high speed LANs while still leaving over an hour 3362 * before rollover. 3363 * 3364 * As reading the *exact* system time is too expensive to be done 3365 * whenever setting up a TCP connection, we increment the time 3366 * offset in two ways. First, a small random positive increment 3367 * is added to isn_offset for each connection that is set up. 3368 * Second, the function tcp_isn_tick fires once per clock tick 3369 * and increments isn_offset as necessary so that sequence numbers 3370 * are incremented at approximately ISN_BYTES_PER_SECOND. The 3371 * random positive increments serve only to ensure that the same 3372 * exact sequence number is never sent out twice (as could otherwise 3373 * happen when a port is recycled in less than the system tick 3374 * interval.) 3375 * 3376 * net.inet.tcp.isn_reseed_interval controls the number of seconds 3377 * between seeding of isn_secret. This is normally set to zero, 3378 * as reseeding should not be necessary. 3379 * 3380 * Locking of the global variables isn_secret, isn_last_reseed, isn_offset, 3381 * isn_offset_old, and isn_ctx is performed using the ISN lock. In 3382 * general, this means holding an exclusive (write) lock. 3383 */ 3384 3385 #define ISN_BYTES_PER_SECOND 1048576 3386 #define ISN_STATIC_INCREMENT 4096 3387 #define ISN_RANDOM_INCREMENT (4096 - 1) 3388 #define ISN_SECRET_LENGTH SIPHASH_KEY_LENGTH 3389 3390 VNET_DEFINE_STATIC(u_char, isn_secret[ISN_SECRET_LENGTH]); 3391 VNET_DEFINE_STATIC(int, isn_last); 3392 VNET_DEFINE_STATIC(int, isn_last_reseed); 3393 VNET_DEFINE_STATIC(u_int32_t, isn_offset); 3394 VNET_DEFINE_STATIC(u_int32_t, isn_offset_old); 3395 3396 #define V_isn_secret VNET(isn_secret) 3397 #define V_isn_last VNET(isn_last) 3398 #define V_isn_last_reseed VNET(isn_last_reseed) 3399 #define V_isn_offset VNET(isn_offset) 3400 #define V_isn_offset_old VNET(isn_offset_old) 3401 3402 tcp_seq 3403 tcp_new_isn(struct in_conninfo *inc) 3404 { 3405 tcp_seq new_isn; 3406 u_int32_t projected_offset; 3407 3408 ISN_LOCK(); 3409 /* Seed if this is the first use, reseed if requested. */ 3410 if ((V_isn_last_reseed == 0) || ((V_tcp_isn_reseed_interval > 0) && 3411 (((u_int)V_isn_last_reseed + (u_int)V_tcp_isn_reseed_interval*hz) 3412 < (u_int)ticks))) { 3413 arc4rand(&V_isn_secret, sizeof(V_isn_secret), 0); 3414 V_isn_last_reseed = ticks; 3415 } 3416 3417 /* Compute the hash and return the ISN. */ 3418 new_isn = (tcp_seq)tcp_keyed_hash(inc, V_isn_secret, 3419 sizeof(V_isn_secret)); 3420 V_isn_offset += ISN_STATIC_INCREMENT + 3421 (arc4random() & ISN_RANDOM_INCREMENT); 3422 if (ticks != V_isn_last) { 3423 projected_offset = V_isn_offset_old + 3424 ISN_BYTES_PER_SECOND / hz * (ticks - V_isn_last); 3425 if (SEQ_GT(projected_offset, V_isn_offset)) 3426 V_isn_offset = projected_offset; 3427 V_isn_offset_old = V_isn_offset; 3428 V_isn_last = ticks; 3429 } 3430 new_isn += V_isn_offset; 3431 ISN_UNLOCK(); 3432 return (new_isn); 3433 } 3434 3435 /* 3436 * When a specific ICMP unreachable message is received and the 3437 * connection state is SYN-SENT, drop the connection. This behavior 3438 * is controlled by the icmp_may_rst sysctl. 3439 */ 3440 struct inpcb * 3441 tcp_drop_syn_sent(struct inpcb *inp, int errno) 3442 { 3443 struct tcpcb *tp; 3444 3445 NET_EPOCH_ASSERT(); 3446 INP_WLOCK_ASSERT(inp); 3447 3448 if ((inp->inp_flags & INP_TIMEWAIT) || 3449 (inp->inp_flags & INP_DROPPED)) 3450 return (inp); 3451 3452 tp = intotcpcb(inp); 3453 if (tp->t_state != TCPS_SYN_SENT) 3454 return (inp); 3455 3456 if (IS_FASTOPEN(tp->t_flags)) 3457 tcp_fastopen_disable_path(tp); 3458 3459 tp = tcp_drop(tp, errno); 3460 if (tp != NULL) 3461 return (inp); 3462 else 3463 return (NULL); 3464 } 3465 3466 /* 3467 * When `need fragmentation' ICMP is received, update our idea of the MSS 3468 * based on the new value. Also nudge TCP to send something, since we 3469 * know the packet we just sent was dropped. 3470 * This duplicates some code in the tcp_mss() function in tcp_input.c. 3471 */ 3472 static struct inpcb * 3473 tcp_mtudisc_notify(struct inpcb *inp, int error) 3474 { 3475 3476 tcp_mtudisc(inp, -1); 3477 return (inp); 3478 } 3479 3480 static void 3481 tcp_mtudisc(struct inpcb *inp, int mtuoffer) 3482 { 3483 struct tcpcb *tp; 3484 struct socket *so; 3485 3486 INP_WLOCK_ASSERT(inp); 3487 if ((inp->inp_flags & INP_TIMEWAIT) || 3488 (inp->inp_flags & INP_DROPPED)) 3489 return; 3490 3491 tp = intotcpcb(inp); 3492 KASSERT(tp != NULL, ("tcp_mtudisc: tp == NULL")); 3493 3494 tcp_mss_update(tp, -1, mtuoffer, NULL, NULL); 3495 3496 so = inp->inp_socket; 3497 SOCKBUF_LOCK(&so->so_snd); 3498 /* If the mss is larger than the socket buffer, decrease the mss. */ 3499 if (so->so_snd.sb_hiwat < tp->t_maxseg) 3500 tp->t_maxseg = so->so_snd.sb_hiwat; 3501 SOCKBUF_UNLOCK(&so->so_snd); 3502 3503 TCPSTAT_INC(tcps_mturesent); 3504 tp->t_rtttime = 0; 3505 tp->snd_nxt = tp->snd_una; 3506 tcp_free_sackholes(tp); 3507 tp->snd_recover = tp->snd_max; 3508 if (tp->t_flags & TF_SACK_PERMIT) 3509 EXIT_FASTRECOVERY(tp->t_flags); 3510 if (tp->t_fb->tfb_tcp_mtu_chg != NULL) { 3511 /* 3512 * Conceptually the snd_nxt setting 3513 * and freeing sack holes should 3514 * be done by the default stacks 3515 * own tfb_tcp_mtu_chg(). 3516 */ 3517 tp->t_fb->tfb_tcp_mtu_chg(tp); 3518 } 3519 tp->t_fb->tfb_tcp_output(tp); 3520 } 3521 3522 #ifdef INET 3523 /* 3524 * Look-up the routing entry to the peer of this inpcb. If no route 3525 * is found and it cannot be allocated, then return 0. This routine 3526 * is called by TCP routines that access the rmx structure and by 3527 * tcp_mss_update to get the peer/interface MTU. 3528 */ 3529 uint32_t 3530 tcp_maxmtu(struct in_conninfo *inc, struct tcp_ifcap *cap) 3531 { 3532 struct nhop_object *nh; 3533 struct ifnet *ifp; 3534 uint32_t maxmtu = 0; 3535 3536 KASSERT(inc != NULL, ("tcp_maxmtu with NULL in_conninfo pointer")); 3537 3538 if (inc->inc_faddr.s_addr != INADDR_ANY) { 3539 nh = fib4_lookup(inc->inc_fibnum, inc->inc_faddr, 0, NHR_NONE, 0); 3540 if (nh == NULL) 3541 return (0); 3542 3543 ifp = nh->nh_ifp; 3544 maxmtu = nh->nh_mtu; 3545 3546 /* Report additional interface capabilities. */ 3547 if (cap != NULL) { 3548 if (ifp->if_capenable & IFCAP_TSO4 && 3549 ifp->if_hwassist & CSUM_TSO) { 3550 cap->ifcap |= CSUM_TSO; 3551 cap->tsomax = ifp->if_hw_tsomax; 3552 cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount; 3553 cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize; 3554 } 3555 } 3556 } 3557 return (maxmtu); 3558 } 3559 #endif /* INET */ 3560 3561 #ifdef INET6 3562 uint32_t 3563 tcp_maxmtu6(struct in_conninfo *inc, struct tcp_ifcap *cap) 3564 { 3565 struct nhop_object *nh; 3566 struct in6_addr dst6; 3567 uint32_t scopeid; 3568 struct ifnet *ifp; 3569 uint32_t maxmtu = 0; 3570 3571 KASSERT(inc != NULL, ("tcp_maxmtu6 with NULL in_conninfo pointer")); 3572 3573 if (inc->inc_flags & INC_IPV6MINMTU) 3574 return (IPV6_MMTU); 3575 3576 if (!IN6_IS_ADDR_UNSPECIFIED(&inc->inc6_faddr)) { 3577 in6_splitscope(&inc->inc6_faddr, &dst6, &scopeid); 3578 nh = fib6_lookup(inc->inc_fibnum, &dst6, scopeid, NHR_NONE, 0); 3579 if (nh == NULL) 3580 return (0); 3581 3582 ifp = nh->nh_ifp; 3583 maxmtu = nh->nh_mtu; 3584 3585 /* Report additional interface capabilities. */ 3586 if (cap != NULL) { 3587 if (ifp->if_capenable & IFCAP_TSO6 && 3588 ifp->if_hwassist & CSUM_TSO) { 3589 cap->ifcap |= CSUM_TSO; 3590 cap->tsomax = ifp->if_hw_tsomax; 3591 cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount; 3592 cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize; 3593 } 3594 } 3595 } 3596 3597 return (maxmtu); 3598 } 3599 3600 /* 3601 * Handle setsockopt(IPV6_USE_MIN_MTU) by a TCP stack. 3602 * 3603 * XXXGL: we are updating inpcb here with INC_IPV6MINMTU flag. 3604 * The right place to do that is ip6_setpktopt() that has just been 3605 * executed. By the way it just filled ip6po_minmtu for us. 3606 */ 3607 void 3608 tcp6_use_min_mtu(struct tcpcb *tp) 3609 { 3610 struct inpcb *inp = tp->t_inpcb; 3611 3612 INP_WLOCK_ASSERT(inp); 3613 /* 3614 * In case of the IPV6_USE_MIN_MTU socket 3615 * option, the INC_IPV6MINMTU flag to announce 3616 * a corresponding MSS during the initial 3617 * handshake. If the TCP connection is not in 3618 * the front states, just reduce the MSS being 3619 * used. This avoids the sending of TCP 3620 * segments which will be fragmented at the 3621 * IPv6 layer. 3622 */ 3623 inp->inp_inc.inc_flags |= INC_IPV6MINMTU; 3624 if ((tp->t_state >= TCPS_SYN_SENT) && 3625 (inp->inp_inc.inc_flags & INC_ISIPV6)) { 3626 struct ip6_pktopts *opt; 3627 3628 opt = inp->in6p_outputopts; 3629 if (opt != NULL && opt->ip6po_minmtu == IP6PO_MINMTU_ALL && 3630 tp->t_maxseg > TCP6_MSS) 3631 tp->t_maxseg = TCP6_MSS; 3632 } 3633 } 3634 #endif /* INET6 */ 3635 3636 /* 3637 * Calculate effective SMSS per RFC5681 definition for a given TCP 3638 * connection at its current state, taking into account SACK and etc. 3639 */ 3640 u_int 3641 tcp_maxseg(const struct tcpcb *tp) 3642 { 3643 u_int optlen; 3644 3645 if (tp->t_flags & TF_NOOPT) 3646 return (tp->t_maxseg); 3647 3648 /* 3649 * Here we have a simplified code from tcp_addoptions(), 3650 * without a proper loop, and having most of paddings hardcoded. 3651 * We might make mistakes with padding here in some edge cases, 3652 * but this is harmless, since result of tcp_maxseg() is used 3653 * only in cwnd and ssthresh estimations. 3654 */ 3655 if (TCPS_HAVEESTABLISHED(tp->t_state)) { 3656 if (tp->t_flags & TF_RCVD_TSTMP) 3657 optlen = TCPOLEN_TSTAMP_APPA; 3658 else 3659 optlen = 0; 3660 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3661 if (tp->t_flags & TF_SIGNATURE) 3662 optlen += PADTCPOLEN(TCPOLEN_SIGNATURE); 3663 #endif 3664 if ((tp->t_flags & TF_SACK_PERMIT) && tp->rcv_numsacks > 0) { 3665 optlen += TCPOLEN_SACKHDR; 3666 optlen += tp->rcv_numsacks * TCPOLEN_SACK; 3667 optlen = PADTCPOLEN(optlen); 3668 } 3669 } else { 3670 if (tp->t_flags & TF_REQ_TSTMP) 3671 optlen = TCPOLEN_TSTAMP_APPA; 3672 else 3673 optlen = PADTCPOLEN(TCPOLEN_MAXSEG); 3674 if (tp->t_flags & TF_REQ_SCALE) 3675 optlen += PADTCPOLEN(TCPOLEN_WINDOW); 3676 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3677 if (tp->t_flags & TF_SIGNATURE) 3678 optlen += PADTCPOLEN(TCPOLEN_SIGNATURE); 3679 #endif 3680 if (tp->t_flags & TF_SACK_PERMIT) 3681 optlen += PADTCPOLEN(TCPOLEN_SACK_PERMITTED); 3682 } 3683 #undef PAD 3684 optlen = min(optlen, TCP_MAXOLEN); 3685 return (tp->t_maxseg - optlen); 3686 } 3687 3688 3689 u_int 3690 tcp_fixed_maxseg(const struct tcpcb *tp) 3691 { 3692 int optlen; 3693 3694 if (tp->t_flags & TF_NOOPT) 3695 return (tp->t_maxseg); 3696 3697 /* 3698 * Here we have a simplified code from tcp_addoptions(), 3699 * without a proper loop, and having most of paddings hardcoded. 3700 * We only consider fixed options that we would send every 3701 * time I.e. SACK is not considered. This is important 3702 * for cc modules to figure out what the modulo of the 3703 * cwnd should be. 3704 */ 3705 #define PAD(len) ((((len) / 4) + !!((len) % 4)) * 4) 3706 if (TCPS_HAVEESTABLISHED(tp->t_state)) { 3707 if (tp->t_flags & TF_RCVD_TSTMP) 3708 optlen = TCPOLEN_TSTAMP_APPA; 3709 else 3710 optlen = 0; 3711 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3712 if (tp->t_flags & TF_SIGNATURE) 3713 optlen += PAD(TCPOLEN_SIGNATURE); 3714 #endif 3715 } else { 3716 if (tp->t_flags & TF_REQ_TSTMP) 3717 optlen = TCPOLEN_TSTAMP_APPA; 3718 else 3719 optlen = PAD(TCPOLEN_MAXSEG); 3720 if (tp->t_flags & TF_REQ_SCALE) 3721 optlen += PAD(TCPOLEN_WINDOW); 3722 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3723 if (tp->t_flags & TF_SIGNATURE) 3724 optlen += PAD(TCPOLEN_SIGNATURE); 3725 #endif 3726 if (tp->t_flags & TF_SACK_PERMIT) 3727 optlen += PAD(TCPOLEN_SACK_PERMITTED); 3728 } 3729 #undef PAD 3730 optlen = min(optlen, TCP_MAXOLEN); 3731 return (tp->t_maxseg - optlen); 3732 } 3733 3734 3735 3736 static int 3737 sysctl_drop(SYSCTL_HANDLER_ARGS) 3738 { 3739 /* addrs[0] is a foreign socket, addrs[1] is a local one. */ 3740 struct sockaddr_storage addrs[2]; 3741 struct inpcb *inp; 3742 struct tcpcb *tp; 3743 struct tcptw *tw; 3744 struct sockaddr_in *fin, *lin; 3745 struct epoch_tracker et; 3746 #ifdef INET6 3747 struct sockaddr_in6 *fin6, *lin6; 3748 #endif 3749 int error; 3750 3751 inp = NULL; 3752 fin = lin = NULL; 3753 #ifdef INET6 3754 fin6 = lin6 = NULL; 3755 #endif 3756 error = 0; 3757 3758 if (req->oldptr != NULL || req->oldlen != 0) 3759 return (EINVAL); 3760 if (req->newptr == NULL) 3761 return (EPERM); 3762 if (req->newlen < sizeof(addrs)) 3763 return (ENOMEM); 3764 error = SYSCTL_IN(req, &addrs, sizeof(addrs)); 3765 if (error) 3766 return (error); 3767 3768 switch (addrs[0].ss_family) { 3769 #ifdef INET6 3770 case AF_INET6: 3771 fin6 = (struct sockaddr_in6 *)&addrs[0]; 3772 lin6 = (struct sockaddr_in6 *)&addrs[1]; 3773 if (fin6->sin6_len != sizeof(struct sockaddr_in6) || 3774 lin6->sin6_len != sizeof(struct sockaddr_in6)) 3775 return (EINVAL); 3776 if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr)) { 3777 if (!IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr)) 3778 return (EINVAL); 3779 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[0]); 3780 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[1]); 3781 fin = (struct sockaddr_in *)&addrs[0]; 3782 lin = (struct sockaddr_in *)&addrs[1]; 3783 break; 3784 } 3785 error = sa6_embedscope(fin6, V_ip6_use_defzone); 3786 if (error) 3787 return (error); 3788 error = sa6_embedscope(lin6, V_ip6_use_defzone); 3789 if (error) 3790 return (error); 3791 break; 3792 #endif 3793 #ifdef INET 3794 case AF_INET: 3795 fin = (struct sockaddr_in *)&addrs[0]; 3796 lin = (struct sockaddr_in *)&addrs[1]; 3797 if (fin->sin_len != sizeof(struct sockaddr_in) || 3798 lin->sin_len != sizeof(struct sockaddr_in)) 3799 return (EINVAL); 3800 break; 3801 #endif 3802 default: 3803 return (EINVAL); 3804 } 3805 NET_EPOCH_ENTER(et); 3806 switch (addrs[0].ss_family) { 3807 #ifdef INET6 3808 case AF_INET6: 3809 inp = in6_pcblookup(&V_tcbinfo, &fin6->sin6_addr, 3810 fin6->sin6_port, &lin6->sin6_addr, lin6->sin6_port, 3811 INPLOOKUP_WLOCKPCB, NULL); 3812 break; 3813 #endif 3814 #ifdef INET 3815 case AF_INET: 3816 inp = in_pcblookup(&V_tcbinfo, fin->sin_addr, fin->sin_port, 3817 lin->sin_addr, lin->sin_port, INPLOOKUP_WLOCKPCB, NULL); 3818 break; 3819 #endif 3820 } 3821 if (inp != NULL) { 3822 if (inp->inp_flags & INP_TIMEWAIT) { 3823 /* 3824 * XXXRW: There currently exists a state where an 3825 * inpcb is present, but its timewait state has been 3826 * discarded. For now, don't allow dropping of this 3827 * type of inpcb. 3828 */ 3829 tw = intotw(inp); 3830 if (tw != NULL) 3831 tcp_twclose(tw, 0); 3832 else 3833 INP_WUNLOCK(inp); 3834 } else if ((inp->inp_flags & INP_DROPPED) == 0 && 3835 !SOLISTENING(inp->inp_socket)) { 3836 tp = intotcpcb(inp); 3837 tp = tcp_drop(tp, ECONNABORTED); 3838 if (tp != NULL) 3839 INP_WUNLOCK(inp); 3840 } else 3841 INP_WUNLOCK(inp); 3842 } else 3843 error = ESRCH; 3844 NET_EPOCH_EXIT(et); 3845 return (error); 3846 } 3847 3848 SYSCTL_PROC(_net_inet_tcp, TCPCTL_DROP, drop, 3849 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | 3850 CTLFLAG_NEEDGIANT, NULL, 0, sysctl_drop, "", 3851 "Drop TCP connection"); 3852 3853 #ifdef KERN_TLS 3854 static int 3855 sysctl_switch_tls(SYSCTL_HANDLER_ARGS) 3856 { 3857 /* addrs[0] is a foreign socket, addrs[1] is a local one. */ 3858 struct sockaddr_storage addrs[2]; 3859 struct inpcb *inp; 3860 struct sockaddr_in *fin, *lin; 3861 struct epoch_tracker et; 3862 #ifdef INET6 3863 struct sockaddr_in6 *fin6, *lin6; 3864 #endif 3865 int error; 3866 3867 inp = NULL; 3868 fin = lin = NULL; 3869 #ifdef INET6 3870 fin6 = lin6 = NULL; 3871 #endif 3872 error = 0; 3873 3874 if (req->oldptr != NULL || req->oldlen != 0) 3875 return (EINVAL); 3876 if (req->newptr == NULL) 3877 return (EPERM); 3878 if (req->newlen < sizeof(addrs)) 3879 return (ENOMEM); 3880 error = SYSCTL_IN(req, &addrs, sizeof(addrs)); 3881 if (error) 3882 return (error); 3883 3884 switch (addrs[0].ss_family) { 3885 #ifdef INET6 3886 case AF_INET6: 3887 fin6 = (struct sockaddr_in6 *)&addrs[0]; 3888 lin6 = (struct sockaddr_in6 *)&addrs[1]; 3889 if (fin6->sin6_len != sizeof(struct sockaddr_in6) || 3890 lin6->sin6_len != sizeof(struct sockaddr_in6)) 3891 return (EINVAL); 3892 if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr)) { 3893 if (!IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr)) 3894 return (EINVAL); 3895 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[0]); 3896 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[1]); 3897 fin = (struct sockaddr_in *)&addrs[0]; 3898 lin = (struct sockaddr_in *)&addrs[1]; 3899 break; 3900 } 3901 error = sa6_embedscope(fin6, V_ip6_use_defzone); 3902 if (error) 3903 return (error); 3904 error = sa6_embedscope(lin6, V_ip6_use_defzone); 3905 if (error) 3906 return (error); 3907 break; 3908 #endif 3909 #ifdef INET 3910 case AF_INET: 3911 fin = (struct sockaddr_in *)&addrs[0]; 3912 lin = (struct sockaddr_in *)&addrs[1]; 3913 if (fin->sin_len != sizeof(struct sockaddr_in) || 3914 lin->sin_len != sizeof(struct sockaddr_in)) 3915 return (EINVAL); 3916 break; 3917 #endif 3918 default: 3919 return (EINVAL); 3920 } 3921 NET_EPOCH_ENTER(et); 3922 switch (addrs[0].ss_family) { 3923 #ifdef INET6 3924 case AF_INET6: 3925 inp = in6_pcblookup(&V_tcbinfo, &fin6->sin6_addr, 3926 fin6->sin6_port, &lin6->sin6_addr, lin6->sin6_port, 3927 INPLOOKUP_WLOCKPCB, NULL); 3928 break; 3929 #endif 3930 #ifdef INET 3931 case AF_INET: 3932 inp = in_pcblookup(&V_tcbinfo, fin->sin_addr, fin->sin_port, 3933 lin->sin_addr, lin->sin_port, INPLOOKUP_WLOCKPCB, NULL); 3934 break; 3935 #endif 3936 } 3937 NET_EPOCH_EXIT(et); 3938 if (inp != NULL) { 3939 if ((inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) != 0 || 3940 inp->inp_socket == NULL) { 3941 error = ECONNRESET; 3942 INP_WUNLOCK(inp); 3943 } else { 3944 struct socket *so; 3945 3946 so = inp->inp_socket; 3947 soref(so); 3948 error = ktls_set_tx_mode(so, 3949 arg2 == 0 ? TCP_TLS_MODE_SW : TCP_TLS_MODE_IFNET); 3950 INP_WUNLOCK(inp); 3951 sorele(so); 3952 } 3953 } else 3954 error = ESRCH; 3955 return (error); 3956 } 3957 3958 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, switch_to_sw_tls, 3959 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | 3960 CTLFLAG_NEEDGIANT, NULL, 0, sysctl_switch_tls, "", 3961 "Switch TCP connection to SW TLS"); 3962 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, switch_to_ifnet_tls, 3963 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | 3964 CTLFLAG_NEEDGIANT, NULL, 1, sysctl_switch_tls, "", 3965 "Switch TCP connection to ifnet TLS"); 3966 #endif 3967 3968 /* 3969 * Generate a standardized TCP log line for use throughout the 3970 * tcp subsystem. Memory allocation is done with M_NOWAIT to 3971 * allow use in the interrupt context. 3972 * 3973 * NB: The caller MUST free(s, M_TCPLOG) the returned string. 3974 * NB: The function may return NULL if memory allocation failed. 3975 * 3976 * Due to header inclusion and ordering limitations the struct ip 3977 * and ip6_hdr pointers have to be passed as void pointers. 3978 */ 3979 char * 3980 tcp_log_vain(struct in_conninfo *inc, struct tcphdr *th, void *ip4hdr, 3981 const void *ip6hdr) 3982 { 3983 3984 /* Is logging enabled? */ 3985 if (V_tcp_log_in_vain == 0) 3986 return (NULL); 3987 3988 return (tcp_log_addr(inc, th, ip4hdr, ip6hdr)); 3989 } 3990 3991 char * 3992 tcp_log_addrs(struct in_conninfo *inc, struct tcphdr *th, void *ip4hdr, 3993 const void *ip6hdr) 3994 { 3995 3996 /* Is logging enabled? */ 3997 if (tcp_log_debug == 0) 3998 return (NULL); 3999 4000 return (tcp_log_addr(inc, th, ip4hdr, ip6hdr)); 4001 } 4002 4003 static char * 4004 tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th, void *ip4hdr, 4005 const void *ip6hdr) 4006 { 4007 char *s, *sp; 4008 size_t size; 4009 struct ip *ip; 4010 #ifdef INET6 4011 const struct ip6_hdr *ip6; 4012 4013 ip6 = (const struct ip6_hdr *)ip6hdr; 4014 #endif /* INET6 */ 4015 ip = (struct ip *)ip4hdr; 4016 4017 /* 4018 * The log line looks like this: 4019 * "TCP: [1.2.3.4]:50332 to [1.2.3.4]:80 tcpflags 0x2<SYN>" 4020 */ 4021 size = sizeof("TCP: []:12345 to []:12345 tcpflags 0x2<>") + 4022 sizeof(PRINT_TH_FLAGS) + 1 + 4023 #ifdef INET6 4024 2 * INET6_ADDRSTRLEN; 4025 #else 4026 2 * INET_ADDRSTRLEN; 4027 #endif /* INET6 */ 4028 4029 s = malloc(size, M_TCPLOG, M_ZERO|M_NOWAIT); 4030 if (s == NULL) 4031 return (NULL); 4032 4033 strcat(s, "TCP: ["); 4034 sp = s + strlen(s); 4035 4036 if (inc && ((inc->inc_flags & INC_ISIPV6) == 0)) { 4037 inet_ntoa_r(inc->inc_faddr, sp); 4038 sp = s + strlen(s); 4039 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport)); 4040 sp = s + strlen(s); 4041 inet_ntoa_r(inc->inc_laddr, sp); 4042 sp = s + strlen(s); 4043 sprintf(sp, "]:%i", ntohs(inc->inc_lport)); 4044 #ifdef INET6 4045 } else if (inc) { 4046 ip6_sprintf(sp, &inc->inc6_faddr); 4047 sp = s + strlen(s); 4048 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport)); 4049 sp = s + strlen(s); 4050 ip6_sprintf(sp, &inc->inc6_laddr); 4051 sp = s + strlen(s); 4052 sprintf(sp, "]:%i", ntohs(inc->inc_lport)); 4053 } else if (ip6 && th) { 4054 ip6_sprintf(sp, &ip6->ip6_src); 4055 sp = s + strlen(s); 4056 sprintf(sp, "]:%i to [", ntohs(th->th_sport)); 4057 sp = s + strlen(s); 4058 ip6_sprintf(sp, &ip6->ip6_dst); 4059 sp = s + strlen(s); 4060 sprintf(sp, "]:%i", ntohs(th->th_dport)); 4061 #endif /* INET6 */ 4062 #ifdef INET 4063 } else if (ip && th) { 4064 inet_ntoa_r(ip->ip_src, sp); 4065 sp = s + strlen(s); 4066 sprintf(sp, "]:%i to [", ntohs(th->th_sport)); 4067 sp = s + strlen(s); 4068 inet_ntoa_r(ip->ip_dst, sp); 4069 sp = s + strlen(s); 4070 sprintf(sp, "]:%i", ntohs(th->th_dport)); 4071 #endif /* INET */ 4072 } else { 4073 free(s, M_TCPLOG); 4074 return (NULL); 4075 } 4076 sp = s + strlen(s); 4077 if (th) 4078 sprintf(sp, " tcpflags 0x%b", th->th_flags, PRINT_TH_FLAGS); 4079 if (*(s + size - 1) != '\0') 4080 panic("%s: string too long", __func__); 4081 return (s); 4082 } 4083 4084 /* 4085 * A subroutine which makes it easy to track TCP state changes with DTrace. 4086 * This function shouldn't be called for t_state initializations that don't 4087 * correspond to actual TCP state transitions. 4088 */ 4089 void 4090 tcp_state_change(struct tcpcb *tp, int newstate) 4091 { 4092 #if defined(KDTRACE_HOOKS) 4093 int pstate = tp->t_state; 4094 #endif 4095 4096 TCPSTATES_DEC(tp->t_state); 4097 TCPSTATES_INC(newstate); 4098 tp->t_state = newstate; 4099 TCP_PROBE6(state__change, NULL, tp, NULL, tp, NULL, pstate); 4100 } 4101 4102 /* 4103 * Create an external-format (``xtcpcb'') structure using the information in 4104 * the kernel-format tcpcb structure pointed to by tp. This is done to 4105 * reduce the spew of irrelevant information over this interface, to isolate 4106 * user code from changes in the kernel structure, and potentially to provide 4107 * information-hiding if we decide that some of this information should be 4108 * hidden from users. 4109 */ 4110 void 4111 tcp_inptoxtp(const struct inpcb *inp, struct xtcpcb *xt) 4112 { 4113 struct tcpcb *tp = intotcpcb(inp); 4114 struct tcptw *tw = intotw(inp); 4115 sbintime_t now; 4116 4117 bzero(xt, sizeof(*xt)); 4118 if (inp->inp_flags & INP_TIMEWAIT) { 4119 xt->t_state = TCPS_TIME_WAIT; 4120 xt->xt_encaps_port = tw->t_port; 4121 } else { 4122 xt->t_state = tp->t_state; 4123 xt->t_logstate = tp->t_logstate; 4124 xt->t_flags = tp->t_flags; 4125 xt->t_sndzerowin = tp->t_sndzerowin; 4126 xt->t_sndrexmitpack = tp->t_sndrexmitpack; 4127 xt->t_rcvoopack = tp->t_rcvoopack; 4128 xt->t_rcv_wnd = tp->rcv_wnd; 4129 xt->t_snd_wnd = tp->snd_wnd; 4130 xt->t_snd_cwnd = tp->snd_cwnd; 4131 xt->t_snd_ssthresh = tp->snd_ssthresh; 4132 xt->t_dsack_bytes = tp->t_dsack_bytes; 4133 xt->t_dsack_tlp_bytes = tp->t_dsack_tlp_bytes; 4134 xt->t_dsack_pack = tp->t_dsack_pack; 4135 xt->t_maxseg = tp->t_maxseg; 4136 xt->xt_ecn = (tp->t_flags2 & TF2_ECN_PERMIT) ? 1 : 0 + 4137 (tp->t_flags2 & TF2_ACE_PERMIT) ? 2 : 0; 4138 4139 now = getsbinuptime(); 4140 #define COPYTIMER(ttt) do { \ 4141 if (callout_active(&tp->t_timers->ttt)) \ 4142 xt->ttt = (tp->t_timers->ttt.c_time - now) / \ 4143 SBT_1MS; \ 4144 else \ 4145 xt->ttt = 0; \ 4146 } while (0) 4147 COPYTIMER(tt_delack); 4148 COPYTIMER(tt_rexmt); 4149 COPYTIMER(tt_persist); 4150 COPYTIMER(tt_keep); 4151 COPYTIMER(tt_2msl); 4152 #undef COPYTIMER 4153 xt->t_rcvtime = 1000 * (ticks - tp->t_rcvtime) / hz; 4154 4155 xt->xt_encaps_port = tp->t_port; 4156 bcopy(tp->t_fb->tfb_tcp_block_name, xt->xt_stack, 4157 TCP_FUNCTION_NAME_LEN_MAX); 4158 bcopy(CC_ALGO(tp)->name, xt->xt_cc, 4159 TCP_CA_NAME_MAX); 4160 #ifdef TCP_BLACKBOX 4161 (void)tcp_log_get_id(tp, xt->xt_logid); 4162 #endif 4163 } 4164 4165 xt->xt_len = sizeof(struct xtcpcb); 4166 in_pcbtoxinpcb(inp, &xt->xt_inp); 4167 if (inp->inp_socket == NULL) 4168 xt->xt_inp.xi_socket.xso_protocol = IPPROTO_TCP; 4169 } 4170 4171 void 4172 tcp_log_end_status(struct tcpcb *tp, uint8_t status) 4173 { 4174 uint32_t bit, i; 4175 4176 if ((tp == NULL) || 4177 (status > TCP_EI_STATUS_MAX_VALUE) || 4178 (status == 0)) { 4179 /* Invalid */ 4180 return; 4181 } 4182 if (status > (sizeof(uint32_t) * 8)) { 4183 /* Should this be a KASSERT? */ 4184 return; 4185 } 4186 bit = 1U << (status - 1); 4187 if (bit & tp->t_end_info_status) { 4188 /* already logged */ 4189 return; 4190 } 4191 for (i = 0; i < TCP_END_BYTE_INFO; i++) { 4192 if (tp->t_end_info_bytes[i] == TCP_EI_EMPTY_SLOT) { 4193 tp->t_end_info_bytes[i] = status; 4194 tp->t_end_info_status |= bit; 4195 break; 4196 } 4197 } 4198 } 4199 4200 int 4201 tcp_can_enable_pacing(void) 4202 { 4203 4204 if ((tcp_pacing_limit == -1) || 4205 (tcp_pacing_limit > number_of_tcp_connections_pacing)) { 4206 atomic_fetchadd_int(&number_of_tcp_connections_pacing, 1); 4207 shadow_num_connections = number_of_tcp_connections_pacing; 4208 return (1); 4209 } else { 4210 return (0); 4211 } 4212 } 4213 4214 static uint8_t tcp_pacing_warning = 0; 4215 4216 void 4217 tcp_decrement_paced_conn(void) 4218 { 4219 uint32_t ret; 4220 4221 ret = atomic_fetchadd_int(&number_of_tcp_connections_pacing, -1); 4222 shadow_num_connections = number_of_tcp_connections_pacing; 4223 KASSERT(ret != 0, ("tcp_paced_connection_exits -1 would cause wrap?")); 4224 if (ret == 0) { 4225 if (tcp_pacing_limit != -1) { 4226 printf("Warning all pacing is now disabled, count decrements invalidly!\n"); 4227 tcp_pacing_limit = 0; 4228 } else if (tcp_pacing_warning == 0) { 4229 printf("Warning pacing count is invalid, invalid decrement\n"); 4230 tcp_pacing_warning = 1; 4231 } 4232 } 4233 } 4234