1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)tcp_subr.c 8.2 (Berkeley) 5/24/95 32 */ 33 34 #include <sys/cdefs.h> 35 __FBSDID("$FreeBSD$"); 36 37 #include "opt_inet.h" 38 #include "opt_inet6.h" 39 #include "opt_ipsec.h" 40 #include "opt_kern_tls.h" 41 #include "opt_tcpdebug.h" 42 43 #include <sys/param.h> 44 #include <sys/systm.h> 45 #include <sys/arb.h> 46 #include <sys/callout.h> 47 #include <sys/eventhandler.h> 48 #ifdef TCP_HHOOK 49 #include <sys/hhook.h> 50 #endif 51 #include <sys/kernel.h> 52 #ifdef TCP_HHOOK 53 #include <sys/khelp.h> 54 #endif 55 #ifdef KERN_TLS 56 #include <sys/ktls.h> 57 #endif 58 #include <sys/qmath.h> 59 #include <sys/stats.h> 60 #include <sys/sysctl.h> 61 #include <sys/jail.h> 62 #include <sys/malloc.h> 63 #include <sys/refcount.h> 64 #include <sys/mbuf.h> 65 #ifdef INET6 66 #include <sys/domain.h> 67 #endif 68 #include <sys/priv.h> 69 #include <sys/proc.h> 70 #include <sys/sdt.h> 71 #include <sys/socket.h> 72 #include <sys/socketvar.h> 73 #include <sys/protosw.h> 74 #include <sys/random.h> 75 76 #include <vm/uma.h> 77 78 #include <net/route.h> 79 #include <net/route/nhop.h> 80 #include <net/if.h> 81 #include <net/if_var.h> 82 #include <net/vnet.h> 83 84 #include <netinet/in.h> 85 #include <netinet/in_fib.h> 86 #include <netinet/in_kdtrace.h> 87 #include <netinet/in_pcb.h> 88 #include <netinet/in_systm.h> 89 #include <netinet/in_var.h> 90 #include <netinet/ip.h> 91 #include <netinet/ip_icmp.h> 92 #include <netinet/ip_var.h> 93 #ifdef INET6 94 #include <netinet/icmp6.h> 95 #include <netinet/ip6.h> 96 #include <netinet6/in6_fib.h> 97 #include <netinet6/in6_pcb.h> 98 #include <netinet6/ip6_var.h> 99 #include <netinet6/scope6_var.h> 100 #include <netinet6/nd6.h> 101 #endif 102 103 #include <netinet/tcp.h> 104 #ifdef INVARIANTS 105 #define TCPSTATES 106 #endif 107 #include <netinet/tcp_fsm.h> 108 #include <netinet/tcp_seq.h> 109 #include <netinet/tcp_timer.h> 110 #include <netinet/tcp_var.h> 111 #include <netinet/tcp_log_buf.h> 112 #include <netinet/tcp_syncache.h> 113 #include <netinet/tcp_hpts.h> 114 #include <netinet/cc/cc.h> 115 #ifdef INET6 116 #include <netinet6/tcp6_var.h> 117 #endif 118 #include <netinet/tcpip.h> 119 #include <netinet/tcp_fastopen.h> 120 #ifdef TCPPCAP 121 #include <netinet/tcp_pcap.h> 122 #endif 123 #ifdef TCPDEBUG 124 #include <netinet/tcp_debug.h> 125 #endif 126 #ifdef INET6 127 #include <netinet6/ip6protosw.h> 128 #endif 129 #ifdef TCP_OFFLOAD 130 #include <netinet/tcp_offload.h> 131 #endif 132 #include <netinet/udp.h> 133 #include <netinet/udp_var.h> 134 135 #include <netipsec/ipsec_support.h> 136 137 #include <machine/in_cksum.h> 138 #include <crypto/siphash/siphash.h> 139 140 #include <security/mac/mac_framework.h> 141 142 VNET_DEFINE(int, tcp_mssdflt) = TCP_MSS; 143 #ifdef INET6 144 VNET_DEFINE(int, tcp_v6mssdflt) = TCP6_MSS; 145 #endif 146 147 #ifdef NETFLIX_EXP_DETECTION 148 /* Sack attack detection thresholds and such */ 149 SYSCTL_NODE(_net_inet_tcp, OID_AUTO, sack_attack, 150 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 151 "Sack Attack detection thresholds"); 152 int32_t tcp_force_detection = 0; 153 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, force_detection, 154 CTLFLAG_RW, 155 &tcp_force_detection, 0, 156 "Do we force detection even if the INP has it off?"); 157 int32_t tcp_sack_to_ack_thresh = 700; /* 70 % */ 158 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, sack_to_ack_thresh, 159 CTLFLAG_RW, 160 &tcp_sack_to_ack_thresh, 700, 161 "Percentage of sacks to acks we must see above (10.1 percent is 101)?"); 162 int32_t tcp_sack_to_move_thresh = 600; /* 60 % */ 163 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, move_thresh, 164 CTLFLAG_RW, 165 &tcp_sack_to_move_thresh, 600, 166 "Percentage of sack moves we must see above (10.1 percent is 101)"); 167 int32_t tcp_restoral_thresh = 650; /* 65 % (sack:2:ack -5%) */ 168 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, restore_thresh, 169 CTLFLAG_RW, 170 &tcp_restoral_thresh, 550, 171 "Percentage of sack to ack percentage we must see below to restore(10.1 percent is 101)"); 172 int32_t tcp_sad_decay_val = 800; 173 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, decay_per, 174 CTLFLAG_RW, 175 &tcp_sad_decay_val, 800, 176 "The decay percentage (10.1 percent equals 101 )"); 177 int32_t tcp_map_minimum = 500; 178 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, nummaps, 179 CTLFLAG_RW, 180 &tcp_map_minimum, 500, 181 "Number of Map enteries before we start detection"); 182 int32_t tcp_attack_on_turns_on_logging = 0; 183 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, attacks_logged, 184 CTLFLAG_RW, 185 &tcp_attack_on_turns_on_logging, 0, 186 "When we have a positive hit on attack, do we turn on logging?"); 187 int32_t tcp_sad_pacing_interval = 2000; 188 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, sad_pacing_int, 189 CTLFLAG_RW, 190 &tcp_sad_pacing_interval, 2000, 191 "What is the minimum pacing interval for a classified attacker?"); 192 193 int32_t tcp_sad_low_pps = 100; 194 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, sad_low_pps, 195 CTLFLAG_RW, 196 &tcp_sad_low_pps, 100, 197 "What is the input pps that below which we do not decay?"); 198 #endif 199 uint32_t tcp_ack_war_time_window = 1000; 200 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, ack_war_timewindow, 201 CTLFLAG_RW, 202 &tcp_ack_war_time_window, 1000, 203 "If the tcp_stack does ack-war prevention how many milliseconds are in its time window?"); 204 uint32_t tcp_ack_war_cnt = 5; 205 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, ack_war_cnt, 206 CTLFLAG_RW, 207 &tcp_ack_war_cnt, 5, 208 "If the tcp_stack does ack-war prevention how many acks can be sent in its time window?"); 209 210 struct rwlock tcp_function_lock; 211 212 static int 213 sysctl_net_inet_tcp_mss_check(SYSCTL_HANDLER_ARGS) 214 { 215 int error, new; 216 217 new = V_tcp_mssdflt; 218 error = sysctl_handle_int(oidp, &new, 0, req); 219 if (error == 0 && req->newptr) { 220 if (new < TCP_MINMSS) 221 error = EINVAL; 222 else 223 V_tcp_mssdflt = new; 224 } 225 return (error); 226 } 227 228 SYSCTL_PROC(_net_inet_tcp, TCPCTL_MSSDFLT, mssdflt, 229 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 230 &VNET_NAME(tcp_mssdflt), 0, &sysctl_net_inet_tcp_mss_check, "I", 231 "Default TCP Maximum Segment Size"); 232 233 #ifdef INET6 234 static int 235 sysctl_net_inet_tcp_mss_v6_check(SYSCTL_HANDLER_ARGS) 236 { 237 int error, new; 238 239 new = V_tcp_v6mssdflt; 240 error = sysctl_handle_int(oidp, &new, 0, req); 241 if (error == 0 && req->newptr) { 242 if (new < TCP_MINMSS) 243 error = EINVAL; 244 else 245 V_tcp_v6mssdflt = new; 246 } 247 return (error); 248 } 249 250 SYSCTL_PROC(_net_inet_tcp, TCPCTL_V6MSSDFLT, v6mssdflt, 251 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 252 &VNET_NAME(tcp_v6mssdflt), 0, &sysctl_net_inet_tcp_mss_v6_check, "I", 253 "Default TCP Maximum Segment Size for IPv6"); 254 #endif /* INET6 */ 255 256 /* 257 * Minimum MSS we accept and use. This prevents DoS attacks where 258 * we are forced to a ridiculous low MSS like 20 and send hundreds 259 * of packets instead of one. The effect scales with the available 260 * bandwidth and quickly saturates the CPU and network interface 261 * with packet generation and sending. Set to zero to disable MINMSS 262 * checking. This setting prevents us from sending too small packets. 263 */ 264 VNET_DEFINE(int, tcp_minmss) = TCP_MINMSS; 265 SYSCTL_INT(_net_inet_tcp, OID_AUTO, minmss, CTLFLAG_VNET | CTLFLAG_RW, 266 &VNET_NAME(tcp_minmss), 0, 267 "Minimum TCP Maximum Segment Size"); 268 269 VNET_DEFINE(int, tcp_do_rfc1323) = 1; 270 SYSCTL_INT(_net_inet_tcp, TCPCTL_DO_RFC1323, rfc1323, CTLFLAG_VNET | CTLFLAG_RW, 271 &VNET_NAME(tcp_do_rfc1323), 0, 272 "Enable rfc1323 (high performance TCP) extensions"); 273 274 /* 275 * As of June 2021, several TCP stacks violate RFC 7323 from September 2014. 276 * Some stacks negotiate TS, but never send them after connection setup. Some 277 * stacks negotiate TS, but don't send them when sending keep-alive segments. 278 * These include modern widely deployed TCP stacks. 279 * Therefore tolerating violations for now... 280 */ 281 VNET_DEFINE(int, tcp_tolerate_missing_ts) = 1; 282 SYSCTL_INT(_net_inet_tcp, OID_AUTO, tolerate_missing_ts, CTLFLAG_VNET | CTLFLAG_RW, 283 &VNET_NAME(tcp_tolerate_missing_ts), 0, 284 "Tolerate missing TCP timestamps"); 285 286 VNET_DEFINE(int, tcp_ts_offset_per_conn) = 1; 287 SYSCTL_INT(_net_inet_tcp, OID_AUTO, ts_offset_per_conn, CTLFLAG_VNET | CTLFLAG_RW, 288 &VNET_NAME(tcp_ts_offset_per_conn), 0, 289 "Initialize TCP timestamps per connection instead of per host pair"); 290 291 /* How many connections are pacing */ 292 static volatile uint32_t number_of_tcp_connections_pacing = 0; 293 static uint32_t shadow_num_connections = 0; 294 295 static int tcp_pacing_limit = 10000; 296 SYSCTL_INT(_net_inet_tcp, OID_AUTO, pacing_limit, CTLFLAG_RW, 297 &tcp_pacing_limit, 1000, 298 "If the TCP stack does pacing, is there a limit (-1 = no, 0 = no pacing N = number of connections)"); 299 300 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, pacing_count, CTLFLAG_RD, 301 &shadow_num_connections, 0, "Number of TCP connections being paced"); 302 303 static int tcp_log_debug = 0; 304 SYSCTL_INT(_net_inet_tcp, OID_AUTO, log_debug, CTLFLAG_RW, 305 &tcp_log_debug, 0, "Log errors caused by incoming TCP segments"); 306 307 static int tcp_tcbhashsize; 308 SYSCTL_INT(_net_inet_tcp, OID_AUTO, tcbhashsize, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, 309 &tcp_tcbhashsize, 0, "Size of TCP control-block hashtable"); 310 311 static int do_tcpdrain = 1; 312 SYSCTL_INT(_net_inet_tcp, OID_AUTO, do_tcpdrain, CTLFLAG_RW, &do_tcpdrain, 0, 313 "Enable tcp_drain routine for extra help when low on mbufs"); 314 315 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, pcbcount, CTLFLAG_VNET | CTLFLAG_RD, 316 &VNET_NAME(tcbinfo.ipi_count), 0, "Number of active PCBs"); 317 318 VNET_DEFINE_STATIC(int, icmp_may_rst) = 1; 319 #define V_icmp_may_rst VNET(icmp_may_rst) 320 SYSCTL_INT(_net_inet_tcp, OID_AUTO, icmp_may_rst, CTLFLAG_VNET | CTLFLAG_RW, 321 &VNET_NAME(icmp_may_rst), 0, 322 "Certain ICMP unreachable messages may abort connections in SYN_SENT"); 323 324 VNET_DEFINE_STATIC(int, tcp_isn_reseed_interval) = 0; 325 #define V_tcp_isn_reseed_interval VNET(tcp_isn_reseed_interval) 326 SYSCTL_INT(_net_inet_tcp, OID_AUTO, isn_reseed_interval, CTLFLAG_VNET | CTLFLAG_RW, 327 &VNET_NAME(tcp_isn_reseed_interval), 0, 328 "Seconds between reseeding of ISN secret"); 329 330 static int tcp_soreceive_stream; 331 SYSCTL_INT(_net_inet_tcp, OID_AUTO, soreceive_stream, CTLFLAG_RDTUN, 332 &tcp_soreceive_stream, 0, "Using soreceive_stream for TCP sockets"); 333 334 VNET_DEFINE(uma_zone_t, sack_hole_zone); 335 #define V_sack_hole_zone VNET(sack_hole_zone) 336 VNET_DEFINE(uint32_t, tcp_map_entries_limit) = 0; /* unlimited */ 337 static int 338 sysctl_net_inet_tcp_map_limit_check(SYSCTL_HANDLER_ARGS) 339 { 340 int error; 341 uint32_t new; 342 343 new = V_tcp_map_entries_limit; 344 error = sysctl_handle_int(oidp, &new, 0, req); 345 if (error == 0 && req->newptr) { 346 /* only allow "0" and value > minimum */ 347 if (new > 0 && new < TCP_MIN_MAP_ENTRIES_LIMIT) 348 error = EINVAL; 349 else 350 V_tcp_map_entries_limit = new; 351 } 352 return (error); 353 } 354 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, map_limit, 355 CTLFLAG_VNET | CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 356 &VNET_NAME(tcp_map_entries_limit), 0, 357 &sysctl_net_inet_tcp_map_limit_check, "IU", 358 "Total sendmap entries limit"); 359 360 VNET_DEFINE(uint32_t, tcp_map_split_limit) = 0; /* unlimited */ 361 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, split_limit, CTLFLAG_VNET | CTLFLAG_RW, 362 &VNET_NAME(tcp_map_split_limit), 0, 363 "Total sendmap split entries limit"); 364 365 #ifdef TCP_HHOOK 366 VNET_DEFINE(struct hhook_head *, tcp_hhh[HHOOK_TCP_LAST+1]); 367 #endif 368 369 #define TS_OFFSET_SECRET_LENGTH SIPHASH_KEY_LENGTH 370 VNET_DEFINE_STATIC(u_char, ts_offset_secret[TS_OFFSET_SECRET_LENGTH]); 371 #define V_ts_offset_secret VNET(ts_offset_secret) 372 373 static int tcp_default_fb_init(struct tcpcb *tp); 374 static void tcp_default_fb_fini(struct tcpcb *tp, int tcb_is_purged); 375 static int tcp_default_handoff_ok(struct tcpcb *tp); 376 static struct inpcb *tcp_notify(struct inpcb *, int); 377 static struct inpcb *tcp_mtudisc_notify(struct inpcb *, int); 378 static struct inpcb *tcp_mtudisc(struct inpcb *, int); 379 static char * tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th, 380 void *ip4hdr, const void *ip6hdr); 381 382 static struct tcp_function_block tcp_def_funcblk = { 383 .tfb_tcp_block_name = "freebsd", 384 .tfb_tcp_output = tcp_default_output, 385 .tfb_tcp_do_segment = tcp_do_segment, 386 .tfb_tcp_ctloutput = tcp_default_ctloutput, 387 .tfb_tcp_handoff_ok = tcp_default_handoff_ok, 388 .tfb_tcp_fb_init = tcp_default_fb_init, 389 .tfb_tcp_fb_fini = tcp_default_fb_fini, 390 }; 391 392 static int tcp_fb_cnt = 0; 393 struct tcp_funchead t_functions; 394 static struct tcp_function_block *tcp_func_set_ptr = &tcp_def_funcblk; 395 396 void 397 tcp_record_dsack(struct tcpcb *tp, tcp_seq start, tcp_seq end, int tlp) 398 { 399 TCPSTAT_INC(tcps_dsack_count); 400 tp->t_dsack_pack++; 401 if (tlp == 0) { 402 if (SEQ_GT(end, start)) { 403 tp->t_dsack_bytes += (end - start); 404 TCPSTAT_ADD(tcps_dsack_bytes, (end - start)); 405 } else { 406 tp->t_dsack_tlp_bytes += (start - end); 407 TCPSTAT_ADD(tcps_dsack_bytes, (start - end)); 408 } 409 } else { 410 if (SEQ_GT(end, start)) { 411 tp->t_dsack_bytes += (end - start); 412 TCPSTAT_ADD(tcps_dsack_tlp_bytes, (end - start)); 413 } else { 414 tp->t_dsack_tlp_bytes += (start - end); 415 TCPSTAT_ADD(tcps_dsack_tlp_bytes, (start - end)); 416 } 417 } 418 } 419 420 static struct tcp_function_block * 421 find_tcp_functions_locked(struct tcp_function_set *fs) 422 { 423 struct tcp_function *f; 424 struct tcp_function_block *blk=NULL; 425 426 TAILQ_FOREACH(f, &t_functions, tf_next) { 427 if (strcmp(f->tf_name, fs->function_set_name) == 0) { 428 blk = f->tf_fb; 429 break; 430 } 431 } 432 return(blk); 433 } 434 435 static struct tcp_function_block * 436 find_tcp_fb_locked(struct tcp_function_block *blk, struct tcp_function **s) 437 { 438 struct tcp_function_block *rblk=NULL; 439 struct tcp_function *f; 440 441 TAILQ_FOREACH(f, &t_functions, tf_next) { 442 if (f->tf_fb == blk) { 443 rblk = blk; 444 if (s) { 445 *s = f; 446 } 447 break; 448 } 449 } 450 return (rblk); 451 } 452 453 struct tcp_function_block * 454 find_and_ref_tcp_functions(struct tcp_function_set *fs) 455 { 456 struct tcp_function_block *blk; 457 458 rw_rlock(&tcp_function_lock); 459 blk = find_tcp_functions_locked(fs); 460 if (blk) 461 refcount_acquire(&blk->tfb_refcnt); 462 rw_runlock(&tcp_function_lock); 463 return(blk); 464 } 465 466 struct tcp_function_block * 467 find_and_ref_tcp_fb(struct tcp_function_block *blk) 468 { 469 struct tcp_function_block *rblk; 470 471 rw_rlock(&tcp_function_lock); 472 rblk = find_tcp_fb_locked(blk, NULL); 473 if (rblk) 474 refcount_acquire(&rblk->tfb_refcnt); 475 rw_runlock(&tcp_function_lock); 476 return(rblk); 477 } 478 479 /* Find a matching alias for the given tcp_function_block. */ 480 int 481 find_tcp_function_alias(struct tcp_function_block *blk, 482 struct tcp_function_set *fs) 483 { 484 struct tcp_function *f; 485 int found; 486 487 found = 0; 488 rw_rlock(&tcp_function_lock); 489 TAILQ_FOREACH(f, &t_functions, tf_next) { 490 if ((f->tf_fb == blk) && 491 (strncmp(f->tf_name, blk->tfb_tcp_block_name, 492 TCP_FUNCTION_NAME_LEN_MAX) != 0)) { 493 /* Matching function block with different name. */ 494 strncpy(fs->function_set_name, f->tf_name, 495 TCP_FUNCTION_NAME_LEN_MAX); 496 found = 1; 497 break; 498 } 499 } 500 /* Null terminate the string appropriately. */ 501 if (found) { 502 fs->function_set_name[TCP_FUNCTION_NAME_LEN_MAX - 1] = '\0'; 503 } else { 504 fs->function_set_name[0] = '\0'; 505 } 506 rw_runlock(&tcp_function_lock); 507 return (found); 508 } 509 510 static struct tcp_function_block * 511 find_and_ref_tcp_default_fb(void) 512 { 513 struct tcp_function_block *rblk; 514 515 rw_rlock(&tcp_function_lock); 516 rblk = tcp_func_set_ptr; 517 refcount_acquire(&rblk->tfb_refcnt); 518 rw_runlock(&tcp_function_lock); 519 return (rblk); 520 } 521 522 void 523 tcp_switch_back_to_default(struct tcpcb *tp) 524 { 525 struct tcp_function_block *tfb; 526 527 KASSERT(tp->t_fb != &tcp_def_funcblk, 528 ("%s: called by the built-in default stack", __func__)); 529 530 /* 531 * Release the old stack. This function will either find a new one 532 * or panic. 533 */ 534 if (tp->t_fb->tfb_tcp_fb_fini != NULL) 535 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 0); 536 refcount_release(&tp->t_fb->tfb_refcnt); 537 538 /* 539 * Now, we'll find a new function block to use. 540 * Start by trying the current user-selected 541 * default, unless this stack is the user-selected 542 * default. 543 */ 544 tfb = find_and_ref_tcp_default_fb(); 545 if (tfb == tp->t_fb) { 546 refcount_release(&tfb->tfb_refcnt); 547 tfb = NULL; 548 } 549 /* Does the stack accept this connection? */ 550 if (tfb != NULL && tfb->tfb_tcp_handoff_ok != NULL && 551 (*tfb->tfb_tcp_handoff_ok)(tp)) { 552 refcount_release(&tfb->tfb_refcnt); 553 tfb = NULL; 554 } 555 /* Try to use that stack. */ 556 if (tfb != NULL) { 557 /* Initialize the new stack. If it succeeds, we are done. */ 558 tp->t_fb = tfb; 559 if (tp->t_fb->tfb_tcp_fb_init == NULL || 560 (*tp->t_fb->tfb_tcp_fb_init)(tp) == 0) 561 return; 562 563 /* 564 * Initialization failed. Release the reference count on 565 * the stack. 566 */ 567 refcount_release(&tfb->tfb_refcnt); 568 } 569 570 /* 571 * If that wasn't feasible, use the built-in default 572 * stack which is not allowed to reject anyone. 573 */ 574 tfb = find_and_ref_tcp_fb(&tcp_def_funcblk); 575 if (tfb == NULL) { 576 /* there always should be a default */ 577 panic("Can't refer to tcp_def_funcblk"); 578 } 579 if (tfb->tfb_tcp_handoff_ok != NULL) { 580 if ((*tfb->tfb_tcp_handoff_ok) (tp)) { 581 /* The default stack cannot say no */ 582 panic("Default stack rejects a new session?"); 583 } 584 } 585 tp->t_fb = tfb; 586 if (tp->t_fb->tfb_tcp_fb_init != NULL && 587 (*tp->t_fb->tfb_tcp_fb_init)(tp)) { 588 /* The default stack cannot fail */ 589 panic("Default stack initialization failed"); 590 } 591 } 592 593 static void 594 tcp_recv_udp_tunneled_packet(struct mbuf *m, int off, struct inpcb *inp, 595 const struct sockaddr *sa, void *ctx) 596 { 597 struct ip *iph; 598 #ifdef INET6 599 struct ip6_hdr *ip6; 600 #endif 601 struct udphdr *uh; 602 struct tcphdr *th; 603 int thlen; 604 uint16_t port; 605 606 TCPSTAT_INC(tcps_tunneled_pkts); 607 if ((m->m_flags & M_PKTHDR) == 0) { 608 /* Can't handle one that is not a pkt hdr */ 609 TCPSTAT_INC(tcps_tunneled_errs); 610 goto out; 611 } 612 thlen = sizeof(struct tcphdr); 613 if (m->m_len < off + sizeof(struct udphdr) + thlen && 614 (m = m_pullup(m, off + sizeof(struct udphdr) + thlen)) == NULL) { 615 TCPSTAT_INC(tcps_tunneled_errs); 616 goto out; 617 } 618 iph = mtod(m, struct ip *); 619 uh = (struct udphdr *)((caddr_t)iph + off); 620 th = (struct tcphdr *)(uh + 1); 621 thlen = th->th_off << 2; 622 if (m->m_len < off + sizeof(struct udphdr) + thlen) { 623 m = m_pullup(m, off + sizeof(struct udphdr) + thlen); 624 if (m == NULL) { 625 TCPSTAT_INC(tcps_tunneled_errs); 626 goto out; 627 } else { 628 iph = mtod(m, struct ip *); 629 uh = (struct udphdr *)((caddr_t)iph + off); 630 th = (struct tcphdr *)(uh + 1); 631 } 632 } 633 m->m_pkthdr.tcp_tun_port = port = uh->uh_sport; 634 bcopy(th, uh, m->m_len - off); 635 m->m_len -= sizeof(struct udphdr); 636 m->m_pkthdr.len -= sizeof(struct udphdr); 637 /* 638 * We use the same algorithm for 639 * both UDP and TCP for c-sum. So 640 * the code in tcp_input will skip 641 * the checksum. So we do nothing 642 * with the flag (m->m_pkthdr.csum_flags). 643 */ 644 switch (iph->ip_v) { 645 #ifdef INET 646 case IPVERSION: 647 iph->ip_len = htons(ntohs(iph->ip_len) - sizeof(struct udphdr)); 648 tcp_input_with_port(&m, &off, IPPROTO_TCP, port); 649 break; 650 #endif 651 #ifdef INET6 652 case IPV6_VERSION >> 4: 653 ip6 = mtod(m, struct ip6_hdr *); 654 ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - sizeof(struct udphdr)); 655 tcp6_input_with_port(&m, &off, IPPROTO_TCP, port); 656 break; 657 #endif 658 default: 659 goto out; 660 break; 661 } 662 return; 663 out: 664 m_freem(m); 665 } 666 667 static int 668 sysctl_net_inet_default_tcp_functions(SYSCTL_HANDLER_ARGS) 669 { 670 int error=ENOENT; 671 struct tcp_function_set fs; 672 struct tcp_function_block *blk; 673 674 memset(&fs, 0, sizeof(fs)); 675 rw_rlock(&tcp_function_lock); 676 blk = find_tcp_fb_locked(tcp_func_set_ptr, NULL); 677 if (blk) { 678 /* Found him */ 679 strcpy(fs.function_set_name, blk->tfb_tcp_block_name); 680 fs.pcbcnt = blk->tfb_refcnt; 681 } 682 rw_runlock(&tcp_function_lock); 683 error = sysctl_handle_string(oidp, fs.function_set_name, 684 sizeof(fs.function_set_name), req); 685 686 /* Check for error or no change */ 687 if (error != 0 || req->newptr == NULL) 688 return(error); 689 690 rw_wlock(&tcp_function_lock); 691 blk = find_tcp_functions_locked(&fs); 692 if ((blk == NULL) || 693 (blk->tfb_flags & TCP_FUNC_BEING_REMOVED)) { 694 error = ENOENT; 695 goto done; 696 } 697 tcp_func_set_ptr = blk; 698 done: 699 rw_wunlock(&tcp_function_lock); 700 return (error); 701 } 702 703 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, functions_default, 704 CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 705 NULL, 0, sysctl_net_inet_default_tcp_functions, "A", 706 "Set/get the default TCP functions"); 707 708 static int 709 sysctl_net_inet_list_available(SYSCTL_HANDLER_ARGS) 710 { 711 int error, cnt, linesz; 712 struct tcp_function *f; 713 char *buffer, *cp; 714 size_t bufsz, outsz; 715 bool alias; 716 717 cnt = 0; 718 rw_rlock(&tcp_function_lock); 719 TAILQ_FOREACH(f, &t_functions, tf_next) { 720 cnt++; 721 } 722 rw_runlock(&tcp_function_lock); 723 724 bufsz = (cnt+2) * ((TCP_FUNCTION_NAME_LEN_MAX * 2) + 13) + 1; 725 buffer = malloc(bufsz, M_TEMP, M_WAITOK); 726 727 error = 0; 728 cp = buffer; 729 730 linesz = snprintf(cp, bufsz, "\n%-32s%c %-32s %s\n", "Stack", 'D', 731 "Alias", "PCB count"); 732 cp += linesz; 733 bufsz -= linesz; 734 outsz = linesz; 735 736 rw_rlock(&tcp_function_lock); 737 TAILQ_FOREACH(f, &t_functions, tf_next) { 738 alias = (f->tf_name != f->tf_fb->tfb_tcp_block_name); 739 linesz = snprintf(cp, bufsz, "%-32s%c %-32s %u\n", 740 f->tf_fb->tfb_tcp_block_name, 741 (f->tf_fb == tcp_func_set_ptr) ? '*' : ' ', 742 alias ? f->tf_name : "-", 743 f->tf_fb->tfb_refcnt); 744 if (linesz >= bufsz) { 745 error = EOVERFLOW; 746 break; 747 } 748 cp += linesz; 749 bufsz -= linesz; 750 outsz += linesz; 751 } 752 rw_runlock(&tcp_function_lock); 753 if (error == 0) 754 error = sysctl_handle_string(oidp, buffer, outsz + 1, req); 755 free(buffer, M_TEMP); 756 return (error); 757 } 758 759 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, functions_available, 760 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT, 761 NULL, 0, sysctl_net_inet_list_available, "A", 762 "list available TCP Function sets"); 763 764 VNET_DEFINE(int, tcp_udp_tunneling_port) = TCP_TUNNELING_PORT_DEFAULT; 765 766 #ifdef INET 767 VNET_DEFINE(struct socket *, udp4_tun_socket) = NULL; 768 #define V_udp4_tun_socket VNET(udp4_tun_socket) 769 #endif 770 #ifdef INET6 771 VNET_DEFINE(struct socket *, udp6_tun_socket) = NULL; 772 #define V_udp6_tun_socket VNET(udp6_tun_socket) 773 #endif 774 775 static void 776 tcp_over_udp_stop(void) 777 { 778 /* 779 * This function assumes sysctl caller holds inp_rinfo_lock() 780 * for writing! 781 */ 782 #ifdef INET 783 if (V_udp4_tun_socket != NULL) { 784 soclose(V_udp4_tun_socket); 785 V_udp4_tun_socket = NULL; 786 } 787 #endif 788 #ifdef INET6 789 if (V_udp6_tun_socket != NULL) { 790 soclose(V_udp6_tun_socket); 791 V_udp6_tun_socket = NULL; 792 } 793 #endif 794 } 795 796 static int 797 tcp_over_udp_start(void) 798 { 799 uint16_t port; 800 int ret; 801 #ifdef INET 802 struct sockaddr_in sin; 803 #endif 804 #ifdef INET6 805 struct sockaddr_in6 sin6; 806 #endif 807 /* 808 * This function assumes sysctl caller holds inp_info_rlock() 809 * for writing! 810 */ 811 port = V_tcp_udp_tunneling_port; 812 if (ntohs(port) == 0) { 813 /* Must have a port set */ 814 return (EINVAL); 815 } 816 #ifdef INET 817 if (V_udp4_tun_socket != NULL) { 818 /* Already running -- must stop first */ 819 return (EALREADY); 820 } 821 #endif 822 #ifdef INET6 823 if (V_udp6_tun_socket != NULL) { 824 /* Already running -- must stop first */ 825 return (EALREADY); 826 } 827 #endif 828 #ifdef INET 829 if ((ret = socreate(PF_INET, &V_udp4_tun_socket, 830 SOCK_DGRAM, IPPROTO_UDP, 831 curthread->td_ucred, curthread))) { 832 tcp_over_udp_stop(); 833 return (ret); 834 } 835 /* Call the special UDP hook. */ 836 if ((ret = udp_set_kernel_tunneling(V_udp4_tun_socket, 837 tcp_recv_udp_tunneled_packet, 838 tcp_ctlinput_viaudp, 839 NULL))) { 840 tcp_over_udp_stop(); 841 return (ret); 842 } 843 /* Ok, we have a socket, bind it to the port. */ 844 memset(&sin, 0, sizeof(struct sockaddr_in)); 845 sin.sin_len = sizeof(struct sockaddr_in); 846 sin.sin_family = AF_INET; 847 sin.sin_port = htons(port); 848 if ((ret = sobind(V_udp4_tun_socket, 849 (struct sockaddr *)&sin, curthread))) { 850 tcp_over_udp_stop(); 851 return (ret); 852 } 853 #endif 854 #ifdef INET6 855 if ((ret = socreate(PF_INET6, &V_udp6_tun_socket, 856 SOCK_DGRAM, IPPROTO_UDP, 857 curthread->td_ucred, curthread))) { 858 tcp_over_udp_stop(); 859 return (ret); 860 } 861 /* Call the special UDP hook. */ 862 if ((ret = udp_set_kernel_tunneling(V_udp6_tun_socket, 863 tcp_recv_udp_tunneled_packet, 864 tcp6_ctlinput_viaudp, 865 NULL))) { 866 tcp_over_udp_stop(); 867 return (ret); 868 } 869 /* Ok, we have a socket, bind it to the port. */ 870 memset(&sin6, 0, sizeof(struct sockaddr_in6)); 871 sin6.sin6_len = sizeof(struct sockaddr_in6); 872 sin6.sin6_family = AF_INET6; 873 sin6.sin6_port = htons(port); 874 if ((ret = sobind(V_udp6_tun_socket, 875 (struct sockaddr *)&sin6, curthread))) { 876 tcp_over_udp_stop(); 877 return (ret); 878 } 879 #endif 880 return (0); 881 } 882 883 static int 884 sysctl_net_inet_tcp_udp_tunneling_port_check(SYSCTL_HANDLER_ARGS) 885 { 886 int error; 887 uint32_t old, new; 888 889 old = V_tcp_udp_tunneling_port; 890 new = old; 891 error = sysctl_handle_int(oidp, &new, 0, req); 892 if ((error == 0) && 893 (req->newptr != NULL)) { 894 if ((new < TCP_TUNNELING_PORT_MIN) || 895 (new > TCP_TUNNELING_PORT_MAX)) { 896 error = EINVAL; 897 } else { 898 V_tcp_udp_tunneling_port = new; 899 if (old != 0) { 900 tcp_over_udp_stop(); 901 } 902 if (new != 0) { 903 error = tcp_over_udp_start(); 904 } 905 } 906 } 907 return (error); 908 } 909 910 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, udp_tunneling_port, 911 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 912 &VNET_NAME(tcp_udp_tunneling_port), 913 0, &sysctl_net_inet_tcp_udp_tunneling_port_check, "IU", 914 "Tunneling port for tcp over udp"); 915 916 VNET_DEFINE(int, tcp_udp_tunneling_overhead) = TCP_TUNNELING_OVERHEAD_DEFAULT; 917 918 static int 919 sysctl_net_inet_tcp_udp_tunneling_overhead_check(SYSCTL_HANDLER_ARGS) 920 { 921 int error, new; 922 923 new = V_tcp_udp_tunneling_overhead; 924 error = sysctl_handle_int(oidp, &new, 0, req); 925 if (error == 0 && req->newptr) { 926 if ((new < TCP_TUNNELING_OVERHEAD_MIN) || 927 (new > TCP_TUNNELING_OVERHEAD_MAX)) 928 error = EINVAL; 929 else 930 V_tcp_udp_tunneling_overhead = new; 931 } 932 return (error); 933 } 934 935 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, udp_tunneling_overhead, 936 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 937 &VNET_NAME(tcp_udp_tunneling_overhead), 938 0, &sysctl_net_inet_tcp_udp_tunneling_overhead_check, "IU", 939 "MSS reduction when using tcp over udp"); 940 941 /* 942 * Exports one (struct tcp_function_info) for each alias/name. 943 */ 944 static int 945 sysctl_net_inet_list_func_info(SYSCTL_HANDLER_ARGS) 946 { 947 int cnt, error; 948 struct tcp_function *f; 949 struct tcp_function_info tfi; 950 951 /* 952 * We don't allow writes. 953 */ 954 if (req->newptr != NULL) 955 return (EINVAL); 956 957 /* 958 * Wire the old buffer so we can directly copy the functions to 959 * user space without dropping the lock. 960 */ 961 if (req->oldptr != NULL) { 962 error = sysctl_wire_old_buffer(req, 0); 963 if (error) 964 return (error); 965 } 966 967 /* 968 * Walk the list and copy out matching entries. If INVARIANTS 969 * is compiled in, also walk the list to verify the length of 970 * the list matches what we have recorded. 971 */ 972 rw_rlock(&tcp_function_lock); 973 974 cnt = 0; 975 #ifndef INVARIANTS 976 if (req->oldptr == NULL) { 977 cnt = tcp_fb_cnt; 978 goto skip_loop; 979 } 980 #endif 981 TAILQ_FOREACH(f, &t_functions, tf_next) { 982 #ifdef INVARIANTS 983 cnt++; 984 #endif 985 if (req->oldptr != NULL) { 986 bzero(&tfi, sizeof(tfi)); 987 tfi.tfi_refcnt = f->tf_fb->tfb_refcnt; 988 tfi.tfi_id = f->tf_fb->tfb_id; 989 (void)strlcpy(tfi.tfi_alias, f->tf_name, 990 sizeof(tfi.tfi_alias)); 991 (void)strlcpy(tfi.tfi_name, 992 f->tf_fb->tfb_tcp_block_name, sizeof(tfi.tfi_name)); 993 error = SYSCTL_OUT(req, &tfi, sizeof(tfi)); 994 /* 995 * Don't stop on error, as that is the 996 * mechanism we use to accumulate length 997 * information if the buffer was too short. 998 */ 999 } 1000 } 1001 KASSERT(cnt == tcp_fb_cnt, 1002 ("%s: cnt (%d) != tcp_fb_cnt (%d)", __func__, cnt, tcp_fb_cnt)); 1003 #ifndef INVARIANTS 1004 skip_loop: 1005 #endif 1006 rw_runlock(&tcp_function_lock); 1007 if (req->oldptr == NULL) 1008 error = SYSCTL_OUT(req, NULL, 1009 (cnt + 1) * sizeof(struct tcp_function_info)); 1010 1011 return (error); 1012 } 1013 1014 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, function_info, 1015 CTLTYPE_OPAQUE | CTLFLAG_SKIP | CTLFLAG_RD | CTLFLAG_MPSAFE, 1016 NULL, 0, sysctl_net_inet_list_func_info, "S,tcp_function_info", 1017 "List TCP function block name-to-ID mappings"); 1018 1019 /* 1020 * tfb_tcp_handoff_ok() function for the default stack. 1021 * Note that we'll basically try to take all comers. 1022 */ 1023 static int 1024 tcp_default_handoff_ok(struct tcpcb *tp) 1025 { 1026 1027 return (0); 1028 } 1029 1030 /* 1031 * tfb_tcp_fb_init() function for the default stack. 1032 * 1033 * This handles making sure we have appropriate timers set if you are 1034 * transitioning a socket that has some amount of setup done. 1035 * 1036 * The init() fuction from the default can *never* return non-zero i.e. 1037 * it is required to always succeed since it is the stack of last resort! 1038 */ 1039 static int 1040 tcp_default_fb_init(struct tcpcb *tp) 1041 { 1042 1043 struct socket *so; 1044 1045 INP_WLOCK_ASSERT(tp->t_inpcb); 1046 1047 KASSERT(tp->t_state >= 0 && tp->t_state < TCPS_TIME_WAIT, 1048 ("%s: connection %p in unexpected state %d", __func__, tp, 1049 tp->t_state)); 1050 1051 /* 1052 * Nothing to do for ESTABLISHED or LISTEN states. And, we don't 1053 * know what to do for unexpected states (which includes TIME_WAIT). 1054 */ 1055 if (tp->t_state <= TCPS_LISTEN || tp->t_state >= TCPS_TIME_WAIT) 1056 return (0); 1057 1058 /* 1059 * Make sure some kind of transmission timer is set if there is 1060 * outstanding data. 1061 */ 1062 so = tp->t_inpcb->inp_socket; 1063 if ((!TCPS_HAVEESTABLISHED(tp->t_state) || sbavail(&so->so_snd) || 1064 tp->snd_una != tp->snd_max) && !(tcp_timer_active(tp, TT_REXMT) || 1065 tcp_timer_active(tp, TT_PERSIST))) { 1066 /* 1067 * If the session has established and it looks like it should 1068 * be in the persist state, set the persist timer. Otherwise, 1069 * set the retransmit timer. 1070 */ 1071 if (TCPS_HAVEESTABLISHED(tp->t_state) && tp->snd_wnd == 0 && 1072 (int32_t)(tp->snd_nxt - tp->snd_una) < 1073 (int32_t)sbavail(&so->so_snd)) 1074 tcp_setpersist(tp); 1075 else 1076 tcp_timer_activate(tp, TT_REXMT, tp->t_rxtcur); 1077 } 1078 1079 /* All non-embryonic sessions get a keepalive timer. */ 1080 if (!tcp_timer_active(tp, TT_KEEP)) 1081 tcp_timer_activate(tp, TT_KEEP, 1082 TCPS_HAVEESTABLISHED(tp->t_state) ? TP_KEEPIDLE(tp) : 1083 TP_KEEPINIT(tp)); 1084 1085 /* 1086 * Make sure critical variables are initialized 1087 * if transitioning while in Recovery. 1088 */ 1089 if IN_FASTRECOVERY(tp->t_flags) { 1090 if (tp->sackhint.recover_fs == 0) 1091 tp->sackhint.recover_fs = max(1, 1092 tp->snd_nxt - tp->snd_una); 1093 } 1094 1095 return (0); 1096 } 1097 1098 /* 1099 * tfb_tcp_fb_fini() function for the default stack. 1100 * 1101 * This changes state as necessary (or prudent) to prepare for another stack 1102 * to assume responsibility for the connection. 1103 */ 1104 static void 1105 tcp_default_fb_fini(struct tcpcb *tp, int tcb_is_purged) 1106 { 1107 1108 INP_WLOCK_ASSERT(tp->t_inpcb); 1109 return; 1110 } 1111 1112 /* 1113 * Target size of TCP PCB hash tables. Must be a power of two. 1114 * 1115 * Note that this can be overridden by the kernel environment 1116 * variable net.inet.tcp.tcbhashsize 1117 */ 1118 #ifndef TCBHASHSIZE 1119 #define TCBHASHSIZE 0 1120 #endif 1121 1122 /* 1123 * XXX 1124 * Callouts should be moved into struct tcp directly. They are currently 1125 * separate because the tcpcb structure is exported to userland for sysctl 1126 * parsing purposes, which do not know about callouts. 1127 */ 1128 struct tcpcb_mem { 1129 struct tcpcb tcb; 1130 struct tcp_timer tt; 1131 struct cc_var ccv; 1132 #ifdef TCP_HHOOK 1133 struct osd osd; 1134 #endif 1135 }; 1136 1137 VNET_DEFINE_STATIC(uma_zone_t, tcpcb_zone); 1138 #define V_tcpcb_zone VNET(tcpcb_zone) 1139 1140 MALLOC_DEFINE(M_TCPLOG, "tcplog", "TCP address and flags print buffers"); 1141 MALLOC_DEFINE(M_TCPFUNCTIONS, "tcpfunc", "TCP function set memory"); 1142 1143 static struct mtx isn_mtx; 1144 1145 #define ISN_LOCK_INIT() mtx_init(&isn_mtx, "isn_mtx", NULL, MTX_DEF) 1146 #define ISN_LOCK() mtx_lock(&isn_mtx) 1147 #define ISN_UNLOCK() mtx_unlock(&isn_mtx) 1148 1149 /* 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 static void 1426 tcp_vnet_init(void *arg __unused) 1427 { 1428 1429 #ifdef TCP_HHOOK 1430 if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN, 1431 &V_tcp_hhh[HHOOK_TCP_EST_IN], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0) 1432 printf("%s: WARNING: unable to register helper hook\n", __func__); 1433 if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT, 1434 &V_tcp_hhh[HHOOK_TCP_EST_OUT], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0) 1435 printf("%s: WARNING: unable to register helper hook\n", __func__); 1436 #endif 1437 #ifdef STATS 1438 if (tcp_stats_init()) 1439 printf("%s: WARNING: unable to initialise TCP stats\n", 1440 __func__); 1441 #endif 1442 in_pcbinfo_init(&V_tcbinfo, "tcp", tcp_tcbhashsize, tcp_tcbhashsize, 1443 "tcp_inpcb", tcp_inpcb_init); 1444 1445 /* 1446 * These have to be type stable for the benefit of the timers. 1447 */ 1448 V_tcpcb_zone = uma_zcreate("tcpcb", sizeof(struct tcpcb_mem), 1449 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 1450 uma_zone_set_max(V_tcpcb_zone, maxsockets); 1451 uma_zone_set_warning(V_tcpcb_zone, "kern.ipc.maxsockets limit reached"); 1452 1453 tcp_tw_init(); 1454 syncache_init(); 1455 tcp_hc_init(); 1456 1457 TUNABLE_INT_FETCH("net.inet.tcp.sack.enable", &V_tcp_do_sack); 1458 V_sack_hole_zone = uma_zcreate("sackhole", sizeof(struct sackhole), 1459 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 1460 1461 tcp_fastopen_init(); 1462 1463 COUNTER_ARRAY_ALLOC(V_tcps_states, TCP_NSTATES, M_WAITOK); 1464 VNET_PCPUSTAT_ALLOC(tcpstat, M_WAITOK); 1465 1466 V_tcp_msl = TCPTV_MSL; 1467 } 1468 VNET_SYSINIT(tcp_vnet_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, 1469 tcp_vnet_init, NULL); 1470 1471 static void 1472 tcp_init(void *arg __unused) 1473 { 1474 const char *tcbhash_tuneable; 1475 int hashsize; 1476 1477 tcp_reass_global_init(); 1478 1479 /* XXX virtualize those below? */ 1480 tcp_delacktime = TCPTV_DELACK; 1481 tcp_keepinit = TCPTV_KEEP_INIT; 1482 tcp_keepidle = TCPTV_KEEP_IDLE; 1483 tcp_keepintvl = TCPTV_KEEPINTVL; 1484 tcp_maxpersistidle = TCPTV_KEEP_IDLE; 1485 tcp_rexmit_initial = TCPTV_RTOBASE; 1486 if (tcp_rexmit_initial < 1) 1487 tcp_rexmit_initial = 1; 1488 tcp_rexmit_min = TCPTV_MIN; 1489 if (tcp_rexmit_min < 1) 1490 tcp_rexmit_min = 1; 1491 tcp_persmin = TCPTV_PERSMIN; 1492 tcp_persmax = TCPTV_PERSMAX; 1493 tcp_rexmit_slop = TCPTV_CPU_VAR; 1494 tcp_finwait2_timeout = TCPTV_FINWAIT2_TIMEOUT; 1495 1496 /* Setup the tcp function block list */ 1497 TAILQ_INIT(&t_functions); 1498 rw_init(&tcp_function_lock, "tcp_func_lock"); 1499 register_tcp_functions(&tcp_def_funcblk, M_WAITOK); 1500 #ifdef TCP_BLACKBOX 1501 /* Initialize the TCP logging data. */ 1502 tcp_log_init(); 1503 #endif 1504 arc4rand(&V_ts_offset_secret, sizeof(V_ts_offset_secret), 0); 1505 1506 if (tcp_soreceive_stream) { 1507 #ifdef INET 1508 tcp_usrreqs.pru_soreceive = soreceive_stream; 1509 #endif 1510 #ifdef INET6 1511 tcp6_usrreqs.pru_soreceive = soreceive_stream; 1512 #endif /* INET6 */ 1513 } 1514 1515 #ifdef INET6 1516 #define TCP_MINPROTOHDR (sizeof(struct ip6_hdr) + sizeof(struct tcphdr)) 1517 #else /* INET6 */ 1518 #define TCP_MINPROTOHDR (sizeof(struct tcpiphdr)) 1519 #endif /* INET6 */ 1520 if (max_protohdr < TCP_MINPROTOHDR) 1521 max_protohdr = TCP_MINPROTOHDR; 1522 if (max_linkhdr + TCP_MINPROTOHDR > MHLEN) 1523 panic("tcp_init"); 1524 #undef TCP_MINPROTOHDR 1525 1526 ISN_LOCK_INIT(); 1527 EVENTHANDLER_REGISTER(shutdown_pre_sync, tcp_fini, NULL, 1528 SHUTDOWN_PRI_DEFAULT); 1529 EVENTHANDLER_REGISTER(maxsockets_change, tcp_zone_change, NULL, 1530 EVENTHANDLER_PRI_ANY); 1531 1532 tcp_inp_lro_direct_queue = counter_u64_alloc(M_WAITOK); 1533 tcp_inp_lro_wokeup_queue = counter_u64_alloc(M_WAITOK); 1534 tcp_inp_lro_compressed = counter_u64_alloc(M_WAITOK); 1535 tcp_inp_lro_locks_taken = counter_u64_alloc(M_WAITOK); 1536 tcp_extra_mbuf = counter_u64_alloc(M_WAITOK); 1537 tcp_would_have_but = counter_u64_alloc(M_WAITOK); 1538 tcp_comp_total = counter_u64_alloc(M_WAITOK); 1539 tcp_uncomp_total = counter_u64_alloc(M_WAITOK); 1540 tcp_bad_csums = counter_u64_alloc(M_WAITOK); 1541 #ifdef TCPPCAP 1542 tcp_pcap_init(); 1543 #endif 1544 1545 hashsize = TCBHASHSIZE; 1546 tcbhash_tuneable = "net.inet.tcp.tcbhashsize"; 1547 TUNABLE_INT_FETCH(tcbhash_tuneable, &hashsize); 1548 if (hashsize == 0) { 1549 /* 1550 * Auto tune the hash size based on maxsockets. 1551 * A perfect hash would have a 1:1 mapping 1552 * (hashsize = maxsockets) however it's been 1553 * suggested that O(2) average is better. 1554 */ 1555 hashsize = maketcp_hashsize(maxsockets / 4); 1556 /* 1557 * Our historical default is 512, 1558 * do not autotune lower than this. 1559 */ 1560 if (hashsize < 512) 1561 hashsize = 512; 1562 if (bootverbose) 1563 printf("%s: %s auto tuned to %d\n", __func__, 1564 tcbhash_tuneable, hashsize); 1565 } 1566 /* 1567 * We require a hashsize to be a power of two. 1568 * Previously if it was not a power of two we would just reset it 1569 * back to 512, which could be a nasty surprise if you did not notice 1570 * the error message. 1571 * Instead what we do is clip it to the closest power of two lower 1572 * than the specified hash value. 1573 */ 1574 if (!powerof2(hashsize)) { 1575 int oldhashsize = hashsize; 1576 1577 hashsize = maketcp_hashsize(hashsize); 1578 /* prevent absurdly low value */ 1579 if (hashsize < 16) 1580 hashsize = 16; 1581 printf("%s: WARNING: TCB hash size not a power of 2, " 1582 "clipped from %d to %d.\n", __func__, oldhashsize, 1583 hashsize); 1584 } 1585 tcp_tcbhashsize = hashsize; 1586 } 1587 SYSINIT(tcp_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, tcp_init, NULL); 1588 1589 #ifdef VIMAGE 1590 static void 1591 tcp_destroy(void *unused __unused) 1592 { 1593 int n; 1594 #ifdef TCP_HHOOK 1595 int error; 1596 #endif 1597 1598 /* 1599 * All our processes are gone, all our sockets should be cleaned 1600 * up, which means, we should be past the tcp_discardcb() calls. 1601 * Sleep to let all tcpcb timers really disappear and cleanup. 1602 */ 1603 for (;;) { 1604 INP_INFO_WLOCK(&V_tcbinfo); 1605 n = V_tcbinfo.ipi_count; 1606 INP_INFO_WUNLOCK(&V_tcbinfo); 1607 if (n == 0) 1608 break; 1609 pause("tcpdes", hz / 10); 1610 } 1611 tcp_hc_destroy(); 1612 syncache_destroy(); 1613 tcp_tw_destroy(); 1614 in_pcbinfo_destroy(&V_tcbinfo); 1615 /* tcp_discardcb() clears the sack_holes up. */ 1616 uma_zdestroy(V_sack_hole_zone); 1617 uma_zdestroy(V_tcpcb_zone); 1618 1619 /* 1620 * Cannot free the zone until all tcpcbs are released as we attach 1621 * the allocations to them. 1622 */ 1623 tcp_fastopen_destroy(); 1624 1625 COUNTER_ARRAY_FREE(V_tcps_states, TCP_NSTATES); 1626 VNET_PCPUSTAT_FREE(tcpstat); 1627 1628 #ifdef TCP_HHOOK 1629 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_IN]); 1630 if (error != 0) { 1631 printf("%s: WARNING: unable to deregister helper hook " 1632 "type=%d, id=%d: error %d returned\n", __func__, 1633 HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN, error); 1634 } 1635 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_OUT]); 1636 if (error != 0) { 1637 printf("%s: WARNING: unable to deregister helper hook " 1638 "type=%d, id=%d: error %d returned\n", __func__, 1639 HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT, error); 1640 } 1641 #endif 1642 } 1643 VNET_SYSUNINIT(tcp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, tcp_destroy, NULL); 1644 #endif 1645 1646 void 1647 tcp_fini(void *xtp) 1648 { 1649 1650 } 1651 1652 /* 1653 * Fill in the IP and TCP headers for an outgoing packet, given the tcpcb. 1654 * tcp_template used to store this data in mbufs, but we now recopy it out 1655 * of the tcpcb each time to conserve mbufs. 1656 */ 1657 void 1658 tcpip_fillheaders(struct inpcb *inp, uint16_t port, void *ip_ptr, void *tcp_ptr) 1659 { 1660 struct tcphdr *th = (struct tcphdr *)tcp_ptr; 1661 1662 INP_WLOCK_ASSERT(inp); 1663 1664 #ifdef INET6 1665 if ((inp->inp_vflag & INP_IPV6) != 0) { 1666 struct ip6_hdr *ip6; 1667 1668 ip6 = (struct ip6_hdr *)ip_ptr; 1669 ip6->ip6_flow = (ip6->ip6_flow & ~IPV6_FLOWINFO_MASK) | 1670 (inp->inp_flow & IPV6_FLOWINFO_MASK); 1671 ip6->ip6_vfc = (ip6->ip6_vfc & ~IPV6_VERSION_MASK) | 1672 (IPV6_VERSION & IPV6_VERSION_MASK); 1673 if (port == 0) 1674 ip6->ip6_nxt = IPPROTO_TCP; 1675 else 1676 ip6->ip6_nxt = IPPROTO_UDP; 1677 ip6->ip6_plen = htons(sizeof(struct tcphdr)); 1678 ip6->ip6_src = inp->in6p_laddr; 1679 ip6->ip6_dst = inp->in6p_faddr; 1680 } 1681 #endif /* INET6 */ 1682 #if defined(INET6) && defined(INET) 1683 else 1684 #endif 1685 #ifdef INET 1686 { 1687 struct ip *ip; 1688 1689 ip = (struct ip *)ip_ptr; 1690 ip->ip_v = IPVERSION; 1691 ip->ip_hl = 5; 1692 ip->ip_tos = inp->inp_ip_tos; 1693 ip->ip_len = 0; 1694 ip->ip_id = 0; 1695 ip->ip_off = 0; 1696 ip->ip_ttl = inp->inp_ip_ttl; 1697 ip->ip_sum = 0; 1698 if (port == 0) 1699 ip->ip_p = IPPROTO_TCP; 1700 else 1701 ip->ip_p = IPPROTO_UDP; 1702 ip->ip_src = inp->inp_laddr; 1703 ip->ip_dst = inp->inp_faddr; 1704 } 1705 #endif /* INET */ 1706 th->th_sport = inp->inp_lport; 1707 th->th_dport = inp->inp_fport; 1708 th->th_seq = 0; 1709 th->th_ack = 0; 1710 th->th_x2 = 0; 1711 th->th_off = 5; 1712 th->th_flags = 0; 1713 th->th_win = 0; 1714 th->th_urp = 0; 1715 th->th_sum = 0; /* in_pseudo() is called later for ipv4 */ 1716 } 1717 1718 /* 1719 * Create template to be used to send tcp packets on a connection. 1720 * Allocates an mbuf and fills in a skeletal tcp/ip header. The only 1721 * use for this function is in keepalives, which use tcp_respond. 1722 */ 1723 struct tcptemp * 1724 tcpip_maketemplate(struct inpcb *inp) 1725 { 1726 struct tcptemp *t; 1727 1728 t = malloc(sizeof(*t), M_TEMP, M_NOWAIT); 1729 if (t == NULL) 1730 return (NULL); 1731 tcpip_fillheaders(inp, 0, (void *)&t->tt_ipgen, (void *)&t->tt_t); 1732 return (t); 1733 } 1734 1735 /* 1736 * Send a single message to the TCP at address specified by 1737 * the given TCP/IP header. If m == NULL, then we make a copy 1738 * of the tcpiphdr at th and send directly to the addressed host. 1739 * This is used to force keep alive messages out using the TCP 1740 * template for a connection. If flags are given then we send 1741 * a message back to the TCP which originated the segment th, 1742 * and discard the mbuf containing it and any other attached mbufs. 1743 * 1744 * In any case the ack and sequence number of the transmitted 1745 * segment are as specified by the parameters. 1746 * 1747 * NOTE: If m != NULL, then th must point to *inside* the mbuf. 1748 */ 1749 void 1750 tcp_respond(struct tcpcb *tp, void *ipgen, struct tcphdr *th, struct mbuf *m, 1751 tcp_seq ack, tcp_seq seq, int flags) 1752 { 1753 struct tcpopt to; 1754 struct inpcb *inp; 1755 struct ip *ip; 1756 struct mbuf *optm; 1757 struct udphdr *uh = NULL; 1758 struct tcphdr *nth; 1759 struct tcp_log_buffer *lgb; 1760 u_char *optp; 1761 #ifdef INET6 1762 struct ip6_hdr *ip6; 1763 int isipv6; 1764 #endif /* INET6 */ 1765 int optlen, tlen, win, ulen; 1766 bool incl_opts; 1767 uint16_t port; 1768 int output_ret; 1769 #ifdef INVARIANTS 1770 int thflags = th->th_flags; 1771 #endif 1772 1773 KASSERT(tp != NULL || m != NULL, ("tcp_respond: tp and m both NULL")); 1774 NET_EPOCH_ASSERT(); 1775 1776 #ifdef INET6 1777 isipv6 = ((struct ip *)ipgen)->ip_v == (IPV6_VERSION >> 4); 1778 ip6 = ipgen; 1779 #endif /* INET6 */ 1780 ip = ipgen; 1781 1782 if (tp != NULL) { 1783 inp = tp->t_inpcb; 1784 KASSERT(inp != NULL, ("tcp control block w/o inpcb")); 1785 INP_LOCK_ASSERT(inp); 1786 } else 1787 inp = NULL; 1788 1789 if (m != NULL) { 1790 #ifdef INET6 1791 if (isipv6 && ip6 && (ip6->ip6_nxt == IPPROTO_UDP)) 1792 port = m->m_pkthdr.tcp_tun_port; 1793 else 1794 #endif 1795 if (ip && (ip->ip_p == IPPROTO_UDP)) 1796 port = m->m_pkthdr.tcp_tun_port; 1797 else 1798 port = 0; 1799 } else 1800 port = tp->t_port; 1801 1802 incl_opts = false; 1803 win = 0; 1804 if (tp != NULL) { 1805 if (!(flags & TH_RST)) { 1806 win = sbspace(&inp->inp_socket->so_rcv); 1807 if (win > TCP_MAXWIN << tp->rcv_scale) 1808 win = TCP_MAXWIN << tp->rcv_scale; 1809 } 1810 if ((tp->t_flags & TF_NOOPT) == 0) 1811 incl_opts = true; 1812 } 1813 if (m == NULL) { 1814 m = m_gethdr(M_NOWAIT, MT_DATA); 1815 if (m == NULL) 1816 return; 1817 m->m_data += max_linkhdr; 1818 #ifdef INET6 1819 if (isipv6) { 1820 bcopy((caddr_t)ip6, mtod(m, caddr_t), 1821 sizeof(struct ip6_hdr)); 1822 ip6 = mtod(m, struct ip6_hdr *); 1823 nth = (struct tcphdr *)(ip6 + 1); 1824 if (port) { 1825 /* Insert a UDP header */ 1826 uh = (struct udphdr *)nth; 1827 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1828 uh->uh_dport = port; 1829 nth = (struct tcphdr *)(uh + 1); 1830 } 1831 } else 1832 #endif /* INET6 */ 1833 { 1834 bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip)); 1835 ip = mtod(m, struct ip *); 1836 nth = (struct tcphdr *)(ip + 1); 1837 if (port) { 1838 /* Insert a UDP header */ 1839 uh = (struct udphdr *)nth; 1840 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1841 uh->uh_dport = port; 1842 nth = (struct tcphdr *)(uh + 1); 1843 } 1844 } 1845 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr)); 1846 flags = TH_ACK; 1847 } else if ((!M_WRITABLE(m)) || (port != 0)) { 1848 struct mbuf *n; 1849 1850 /* Can't reuse 'm', allocate a new mbuf. */ 1851 n = m_gethdr(M_NOWAIT, MT_DATA); 1852 if (n == NULL) { 1853 m_freem(m); 1854 return; 1855 } 1856 1857 if (!m_dup_pkthdr(n, m, M_NOWAIT)) { 1858 m_freem(m); 1859 m_freem(n); 1860 return; 1861 } 1862 1863 n->m_data += max_linkhdr; 1864 /* m_len is set later */ 1865 #define xchg(a,b,type) { type t; t=a; a=b; b=t; } 1866 #ifdef INET6 1867 if (isipv6) { 1868 bcopy((caddr_t)ip6, mtod(n, caddr_t), 1869 sizeof(struct ip6_hdr)); 1870 ip6 = mtod(n, struct ip6_hdr *); 1871 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); 1872 nth = (struct tcphdr *)(ip6 + 1); 1873 if (port) { 1874 /* Insert a UDP header */ 1875 uh = (struct udphdr *)nth; 1876 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1877 uh->uh_dport = port; 1878 nth = (struct tcphdr *)(uh + 1); 1879 } 1880 } else 1881 #endif /* INET6 */ 1882 { 1883 bcopy((caddr_t)ip, mtod(n, caddr_t), sizeof(struct ip)); 1884 ip = mtod(n, struct ip *); 1885 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t); 1886 nth = (struct tcphdr *)(ip + 1); 1887 if (port) { 1888 /* Insert a UDP header */ 1889 uh = (struct udphdr *)nth; 1890 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1891 uh->uh_dport = port; 1892 nth = (struct tcphdr *)(uh + 1); 1893 } 1894 } 1895 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr)); 1896 xchg(nth->th_dport, nth->th_sport, uint16_t); 1897 th = nth; 1898 m_freem(m); 1899 m = n; 1900 } else { 1901 /* 1902 * reuse the mbuf. 1903 * XXX MRT We inherit the FIB, which is lucky. 1904 */ 1905 m_freem(m->m_next); 1906 m->m_next = NULL; 1907 m->m_data = (caddr_t)ipgen; 1908 /* m_len is set later */ 1909 #ifdef INET6 1910 if (isipv6) { 1911 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); 1912 nth = (struct tcphdr *)(ip6 + 1); 1913 } else 1914 #endif /* INET6 */ 1915 { 1916 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t); 1917 nth = (struct tcphdr *)(ip + 1); 1918 } 1919 if (th != nth) { 1920 /* 1921 * this is usually a case when an extension header 1922 * exists between the IPv6 header and the 1923 * TCP header. 1924 */ 1925 nth->th_sport = th->th_sport; 1926 nth->th_dport = th->th_dport; 1927 } 1928 xchg(nth->th_dport, nth->th_sport, uint16_t); 1929 #undef xchg 1930 } 1931 tlen = 0; 1932 #ifdef INET6 1933 if (isipv6) 1934 tlen = sizeof (struct ip6_hdr) + sizeof (struct tcphdr); 1935 #endif 1936 #if defined(INET) && defined(INET6) 1937 else 1938 #endif 1939 #ifdef INET 1940 tlen = sizeof (struct tcpiphdr); 1941 #endif 1942 if (port) 1943 tlen += sizeof (struct udphdr); 1944 #ifdef INVARIANTS 1945 m->m_len = 0; 1946 KASSERT(M_TRAILINGSPACE(m) >= tlen, 1947 ("Not enough trailing space for message (m=%p, need=%d, have=%ld)", 1948 m, tlen, (long)M_TRAILINGSPACE(m))); 1949 #endif 1950 m->m_len = tlen; 1951 to.to_flags = 0; 1952 if (incl_opts) { 1953 /* Make sure we have room. */ 1954 if (M_TRAILINGSPACE(m) < TCP_MAXOLEN) { 1955 m->m_next = m_get(M_NOWAIT, MT_DATA); 1956 if (m->m_next) { 1957 optp = mtod(m->m_next, u_char *); 1958 optm = m->m_next; 1959 } else 1960 incl_opts = false; 1961 } else { 1962 optp = (u_char *) (nth + 1); 1963 optm = m; 1964 } 1965 } 1966 if (incl_opts) { 1967 /* Timestamps. */ 1968 if (tp->t_flags & TF_RCVD_TSTMP) { 1969 to.to_tsval = tcp_ts_getticks() + tp->ts_offset; 1970 to.to_tsecr = tp->ts_recent; 1971 to.to_flags |= TOF_TS; 1972 } 1973 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 1974 /* TCP-MD5 (RFC2385). */ 1975 if (tp->t_flags & TF_SIGNATURE) 1976 to.to_flags |= TOF_SIGNATURE; 1977 #endif 1978 /* Add the options. */ 1979 tlen += optlen = tcp_addoptions(&to, optp); 1980 1981 /* Update m_len in the correct mbuf. */ 1982 optm->m_len += optlen; 1983 } else 1984 optlen = 0; 1985 #ifdef INET6 1986 if (isipv6) { 1987 if (uh) { 1988 ulen = tlen - sizeof(struct ip6_hdr); 1989 uh->uh_ulen = htons(ulen); 1990 } 1991 ip6->ip6_flow = 0; 1992 ip6->ip6_vfc = IPV6_VERSION; 1993 if (port) 1994 ip6->ip6_nxt = IPPROTO_UDP; 1995 else 1996 ip6->ip6_nxt = IPPROTO_TCP; 1997 ip6->ip6_plen = htons(tlen - sizeof(*ip6)); 1998 } 1999 #endif 2000 #if defined(INET) && defined(INET6) 2001 else 2002 #endif 2003 #ifdef INET 2004 { 2005 if (uh) { 2006 ulen = tlen - sizeof(struct ip); 2007 uh->uh_ulen = htons(ulen); 2008 } 2009 ip->ip_len = htons(tlen); 2010 ip->ip_ttl = V_ip_defttl; 2011 if (port) { 2012 ip->ip_p = IPPROTO_UDP; 2013 } else { 2014 ip->ip_p = IPPROTO_TCP; 2015 } 2016 if (V_path_mtu_discovery) 2017 ip->ip_off |= htons(IP_DF); 2018 } 2019 #endif 2020 m->m_pkthdr.len = tlen; 2021 m->m_pkthdr.rcvif = NULL; 2022 #ifdef MAC 2023 if (inp != NULL) { 2024 /* 2025 * Packet is associated with a socket, so allow the 2026 * label of the response to reflect the socket label. 2027 */ 2028 INP_LOCK_ASSERT(inp); 2029 mac_inpcb_create_mbuf(inp, m); 2030 } else { 2031 /* 2032 * Packet is not associated with a socket, so possibly 2033 * update the label in place. 2034 */ 2035 mac_netinet_tcp_reply(m); 2036 } 2037 #endif 2038 nth->th_seq = htonl(seq); 2039 nth->th_ack = htonl(ack); 2040 nth->th_x2 = 0; 2041 nth->th_off = (sizeof (struct tcphdr) + optlen) >> 2; 2042 nth->th_flags = flags; 2043 if (tp != NULL) 2044 nth->th_win = htons((u_short) (win >> tp->rcv_scale)); 2045 else 2046 nth->th_win = htons((u_short)win); 2047 nth->th_urp = 0; 2048 2049 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 2050 if (to.to_flags & TOF_SIGNATURE) { 2051 if (!TCPMD5_ENABLED() || 2052 TCPMD5_OUTPUT(m, nth, to.to_signature) != 0) { 2053 m_freem(m); 2054 return; 2055 } 2056 } 2057 #endif 2058 2059 #ifdef INET6 2060 if (isipv6) { 2061 if (port) { 2062 m->m_pkthdr.csum_flags = CSUM_UDP_IPV6; 2063 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 2064 uh->uh_sum = in6_cksum_pseudo(ip6, ulen, IPPROTO_UDP, 0); 2065 nth->th_sum = 0; 2066 } else { 2067 m->m_pkthdr.csum_flags = CSUM_TCP_IPV6; 2068 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); 2069 nth->th_sum = in6_cksum_pseudo(ip6, 2070 tlen - sizeof(struct ip6_hdr), IPPROTO_TCP, 0); 2071 } 2072 ip6->ip6_hlim = in6_selecthlim(tp != NULL ? tp->t_inpcb : 2073 NULL, NULL); 2074 } 2075 #endif /* INET6 */ 2076 #if defined(INET6) && defined(INET) 2077 else 2078 #endif 2079 #ifdef INET 2080 { 2081 if (port) { 2082 uh->uh_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, 2083 htons(ulen + IPPROTO_UDP)); 2084 m->m_pkthdr.csum_flags = CSUM_UDP; 2085 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 2086 nth->th_sum = 0; 2087 } else { 2088 m->m_pkthdr.csum_flags = CSUM_TCP; 2089 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); 2090 nth->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, 2091 htons((u_short)(tlen - sizeof(struct ip) + ip->ip_p))); 2092 } 2093 } 2094 #endif /* INET */ 2095 #ifdef TCPDEBUG 2096 if (tp == NULL || (inp->inp_socket->so_options & SO_DEBUG)) 2097 tcp_trace(TA_OUTPUT, 0, tp, mtod(m, void *), th, 0); 2098 #endif 2099 TCP_PROBE3(debug__output, tp, th, m); 2100 if (flags & TH_RST) 2101 TCP_PROBE5(accept__refused, NULL, NULL, m, tp, nth); 2102 lgb = NULL; 2103 if ((tp != NULL) && (tp->t_logstate != TCP_LOG_STATE_OFF)) { 2104 if (INP_WLOCKED(inp)) { 2105 union tcp_log_stackspecific log; 2106 struct timeval tv; 2107 2108 memset(&log.u_bbr, 0, sizeof(log.u_bbr)); 2109 log.u_bbr.inhpts = tp->t_inpcb->inp_in_hpts; 2110 log.u_bbr.flex8 = 4; 2111 log.u_bbr.pkts_out = tp->t_maxseg; 2112 log.u_bbr.timeStamp = tcp_get_usecs(&tv); 2113 log.u_bbr.delivered = 0; 2114 lgb = tcp_log_event_(tp, nth, NULL, NULL, TCP_LOG_OUT, 2115 ERRNO_UNK, 0, &log, false, NULL, NULL, 0, &tv); 2116 } else { 2117 /* 2118 * We can not log the packet, since we only own the 2119 * read lock, but a write lock is needed. The read lock 2120 * is not upgraded to a write lock, since only getting 2121 * the read lock was done intentionally to improve the 2122 * handling of SYN flooding attacks. 2123 * This happens only for pure SYN segments received in 2124 * the initial CLOSED state, or received in a more 2125 * advanced state than listen and the UDP encapsulation 2126 * port is unexpected. 2127 * The incoming SYN segments do not really belong to 2128 * the TCP connection and the handling does not change 2129 * the state of the TCP connection. Therefore, the 2130 * sending of the RST segments is not logged. Please 2131 * note that also the incoming SYN segments are not 2132 * logged. 2133 * 2134 * The following code ensures that the above description 2135 * is and stays correct. 2136 */ 2137 KASSERT((thflags & (TH_ACK|TH_SYN)) == TH_SYN && 2138 (tp->t_state == TCPS_CLOSED || 2139 (tp->t_state > TCPS_LISTEN && tp->t_port != port)), 2140 ("%s: Logging of TCP segment with flags 0x%b and " 2141 "UDP encapsulation port %u skipped in state %s", 2142 __func__, thflags, PRINT_TH_FLAGS, 2143 ntohs(port), tcpstates[tp->t_state])); 2144 } 2145 } 2146 2147 #ifdef INET6 2148 if (isipv6) { 2149 TCP_PROBE5(send, NULL, tp, ip6, tp, nth); 2150 output_ret = ip6_output(m, NULL, NULL, 0, NULL, NULL, inp); 2151 } 2152 #endif /* INET6 */ 2153 #if defined(INET) && defined(INET6) 2154 else 2155 #endif 2156 #ifdef INET 2157 { 2158 TCP_PROBE5(send, NULL, tp, ip, tp, nth); 2159 output_ret = ip_output(m, NULL, NULL, 0, NULL, inp); 2160 } 2161 #endif 2162 if (lgb != NULL) 2163 lgb->tlb_errno = output_ret; 2164 } 2165 2166 /* 2167 * Create a new TCP control block, making an 2168 * empty reassembly queue and hooking it to the argument 2169 * protocol control block. The `inp' parameter must have 2170 * come from the zone allocator set up in tcp_init(). 2171 */ 2172 struct tcpcb * 2173 tcp_newtcpcb(struct inpcb *inp) 2174 { 2175 struct tcpcb_mem *tm; 2176 struct tcpcb *tp; 2177 #ifdef INET6 2178 int isipv6 = (inp->inp_vflag & INP_IPV6) != 0; 2179 #endif /* INET6 */ 2180 2181 tm = uma_zalloc(V_tcpcb_zone, M_NOWAIT | M_ZERO); 2182 if (tm == NULL) 2183 return (NULL); 2184 tp = &tm->tcb; 2185 2186 /* Initialise cc_var struct for this tcpcb. */ 2187 tp->ccv = &tm->ccv; 2188 tp->ccv->type = IPPROTO_TCP; 2189 tp->ccv->ccvc.tcp = tp; 2190 rw_rlock(&tcp_function_lock); 2191 tp->t_fb = tcp_func_set_ptr; 2192 refcount_acquire(&tp->t_fb->tfb_refcnt); 2193 rw_runlock(&tcp_function_lock); 2194 /* 2195 * Use the current system default CC algorithm. 2196 */ 2197 CC_LIST_RLOCK(); 2198 KASSERT(!STAILQ_EMPTY(&cc_list), ("cc_list is empty!")); 2199 CC_ALGO(tp) = CC_DEFAULT_ALGO(); 2200 CC_LIST_RUNLOCK(); 2201 2202 /* 2203 * The tcpcb will hold a reference on its inpcb until tcp_discardcb() 2204 * is called. 2205 */ 2206 in_pcbref(inp); /* Reference for tcpcb */ 2207 tp->t_inpcb = inp; 2208 2209 if (CC_ALGO(tp)->cb_init != NULL) 2210 if (CC_ALGO(tp)->cb_init(tp->ccv, NULL) > 0) { 2211 if (tp->t_fb->tfb_tcp_fb_fini) 2212 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); 2213 in_pcbrele_wlocked(inp); 2214 refcount_release(&tp->t_fb->tfb_refcnt); 2215 uma_zfree(V_tcpcb_zone, tm); 2216 return (NULL); 2217 } 2218 2219 #ifdef TCP_HHOOK 2220 tp->osd = &tm->osd; 2221 if (khelp_init_osd(HELPER_CLASS_TCP, tp->osd)) { 2222 if (tp->t_fb->tfb_tcp_fb_fini) 2223 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); 2224 in_pcbrele_wlocked(inp); 2225 refcount_release(&tp->t_fb->tfb_refcnt); 2226 uma_zfree(V_tcpcb_zone, tm); 2227 return (NULL); 2228 } 2229 #endif 2230 2231 #ifdef VIMAGE 2232 tp->t_vnet = inp->inp_vnet; 2233 #endif 2234 tp->t_timers = &tm->tt; 2235 TAILQ_INIT(&tp->t_segq); 2236 tp->t_maxseg = 2237 #ifdef INET6 2238 isipv6 ? V_tcp_v6mssdflt : 2239 #endif /* INET6 */ 2240 V_tcp_mssdflt; 2241 2242 /* Set up our timeouts. */ 2243 callout_init(&tp->t_timers->tt_rexmt, 1); 2244 callout_init(&tp->t_timers->tt_persist, 1); 2245 callout_init(&tp->t_timers->tt_keep, 1); 2246 callout_init(&tp->t_timers->tt_2msl, 1); 2247 callout_init(&tp->t_timers->tt_delack, 1); 2248 2249 if (V_tcp_do_rfc1323) 2250 tp->t_flags = (TF_REQ_SCALE|TF_REQ_TSTMP); 2251 if (V_tcp_do_sack) 2252 tp->t_flags |= TF_SACK_PERMIT; 2253 TAILQ_INIT(&tp->snd_holes); 2254 2255 /* 2256 * Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no 2257 * rtt estimate. Set rttvar so that srtt + 4 * rttvar gives 2258 * reasonable initial retransmit time. 2259 */ 2260 tp->t_srtt = TCPTV_SRTTBASE; 2261 tp->t_rttvar = ((tcp_rexmit_initial - TCPTV_SRTTBASE) << TCP_RTTVAR_SHIFT) / 4; 2262 tp->t_rttmin = tcp_rexmit_min; 2263 tp->t_rxtcur = tcp_rexmit_initial; 2264 tp->snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT; 2265 tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT; 2266 tp->t_rcvtime = ticks; 2267 /* 2268 * IPv4 TTL initialization is necessary for an IPv6 socket as well, 2269 * because the socket may be bound to an IPv6 wildcard address, 2270 * which may match an IPv4-mapped IPv6 address. 2271 */ 2272 inp->inp_ip_ttl = V_ip_defttl; 2273 inp->inp_ppcb = tp; 2274 #ifdef TCPPCAP 2275 /* 2276 * Init the TCP PCAP queues. 2277 */ 2278 tcp_pcap_tcpcb_init(tp); 2279 #endif 2280 #ifdef TCP_BLACKBOX 2281 /* Initialize the per-TCPCB log data. */ 2282 tcp_log_tcpcbinit(tp); 2283 #endif 2284 tp->t_pacing_rate = -1; 2285 if (tp->t_fb->tfb_tcp_fb_init) { 2286 if ((*tp->t_fb->tfb_tcp_fb_init)(tp)) { 2287 refcount_release(&tp->t_fb->tfb_refcnt); 2288 in_pcbrele_wlocked(inp); 2289 uma_zfree(V_tcpcb_zone, tm); 2290 return (NULL); 2291 } 2292 } 2293 #ifdef STATS 2294 if (V_tcp_perconn_stats_enable == 1) 2295 tp->t_stats = stats_blob_alloc(V_tcp_perconn_stats_dflt_tpl, 0); 2296 #endif 2297 if (V_tcp_do_lrd) 2298 tp->t_flags |= TF_LRD; 2299 return (tp); /* XXX */ 2300 } 2301 2302 /* 2303 * Switch the congestion control algorithm back to Vnet default for any active 2304 * control blocks using an algorithm which is about to go away. If the algorithm 2305 * has a cb_init function and it fails (no memory) then the operation fails and 2306 * the unload will not succeed. 2307 * 2308 */ 2309 int 2310 tcp_ccalgounload(struct cc_algo *unload_algo) 2311 { 2312 struct cc_algo *oldalgo, *newalgo; 2313 struct inpcb *inp; 2314 struct tcpcb *tp; 2315 VNET_ITERATOR_DECL(vnet_iter); 2316 2317 /* 2318 * Check all active control blocks across all network stacks and change 2319 * any that are using "unload_algo" back to its default. If "unload_algo" 2320 * requires cleanup code to be run, call it. 2321 */ 2322 VNET_LIST_RLOCK(); 2323 VNET_FOREACH(vnet_iter) { 2324 CURVNET_SET(vnet_iter); 2325 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, 2326 INPLOOKUP_WLOCKPCB); 2327 /* 2328 * XXXGL: would new accept(2)d connections use algo being 2329 * unloaded? 2330 */ 2331 newalgo = CC_DEFAULT_ALGO(); 2332 while ((inp = inp_next(&inpi)) != NULL) { 2333 /* Important to skip tcptw structs. */ 2334 if (!(inp->inp_flags & INP_TIMEWAIT) && 2335 (tp = intotcpcb(inp)) != NULL) { 2336 /* 2337 * By holding INP_WLOCK here, we are assured 2338 * that the connection is not currently 2339 * executing inside the CC module's functions. 2340 * We attempt to switch to the Vnets default, 2341 * if the init fails then we fail the whole 2342 * operation and the module unload will fail. 2343 */ 2344 if (CC_ALGO(tp) == unload_algo) { 2345 struct cc_var cc_mem; 2346 int err; 2347 2348 oldalgo = CC_ALGO(tp); 2349 memset(&cc_mem, 0, sizeof(cc_mem)); 2350 cc_mem.ccvc.tcp = tp; 2351 if (newalgo->cb_init == NULL) { 2352 /* 2353 * No init we can skip the 2354 * dance around a possible failure. 2355 */ 2356 CC_DATA(tp) = NULL; 2357 goto proceed; 2358 } 2359 err = (newalgo->cb_init)(&cc_mem, NULL); 2360 if (err) { 2361 /* 2362 * Presumably no memory the caller will 2363 * need to try again. 2364 */ 2365 INP_WUNLOCK(inp); 2366 CURVNET_RESTORE(); 2367 VNET_LIST_RUNLOCK(); 2368 return (err); 2369 } 2370 proceed: 2371 if (oldalgo->cb_destroy != NULL) 2372 oldalgo->cb_destroy(tp->ccv); 2373 CC_ALGO(tp) = newalgo; 2374 memcpy(tp->ccv, &cc_mem, sizeof(struct cc_var)); 2375 if (TCPS_HAVEESTABLISHED(tp->t_state) && 2376 (CC_ALGO(tp)->conn_init != NULL)) { 2377 /* Yep run the connection init for the new CC */ 2378 CC_ALGO(tp)->conn_init(tp->ccv); 2379 } 2380 } 2381 } 2382 } 2383 CURVNET_RESTORE(); 2384 } 2385 VNET_LIST_RUNLOCK(); 2386 return (0); 2387 } 2388 2389 /* 2390 * Drop a TCP connection, reporting 2391 * the specified error. If connection is synchronized, 2392 * then send a RST to peer. 2393 */ 2394 struct tcpcb * 2395 tcp_drop(struct tcpcb *tp, int errno) 2396 { 2397 struct socket *so = tp->t_inpcb->inp_socket; 2398 2399 NET_EPOCH_ASSERT(); 2400 INP_WLOCK_ASSERT(tp->t_inpcb); 2401 2402 if (TCPS_HAVERCVDSYN(tp->t_state)) { 2403 tcp_state_change(tp, TCPS_CLOSED); 2404 /* Don't use tcp_output() here due to possible recursion. */ 2405 (void)tcp_output_nodrop(tp); 2406 TCPSTAT_INC(tcps_drops); 2407 } else 2408 TCPSTAT_INC(tcps_conndrops); 2409 if (errno == ETIMEDOUT && tp->t_softerror) 2410 errno = tp->t_softerror; 2411 so->so_error = errno; 2412 return (tcp_close(tp)); 2413 } 2414 2415 void 2416 tcp_discardcb(struct tcpcb *tp) 2417 { 2418 struct inpcb *inp = tp->t_inpcb; 2419 2420 INP_WLOCK_ASSERT(inp); 2421 2422 /* 2423 * Make sure that all of our timers are stopped before we delete the 2424 * PCB. 2425 * 2426 * If stopping a timer fails, we schedule a discard function in same 2427 * callout, and the last discard function called will take care of 2428 * deleting the tcpcb. 2429 */ 2430 tp->t_timers->tt_draincnt = 0; 2431 tcp_timer_stop(tp, TT_REXMT); 2432 tcp_timer_stop(tp, TT_PERSIST); 2433 tcp_timer_stop(tp, TT_KEEP); 2434 tcp_timer_stop(tp, TT_2MSL); 2435 tcp_timer_stop(tp, TT_DELACK); 2436 if (tp->t_fb->tfb_tcp_timer_stop_all) { 2437 /* 2438 * Call the stop-all function of the methods, 2439 * this function should call the tcp_timer_stop() 2440 * method with each of the function specific timeouts. 2441 * That stop will be called via the tfb_tcp_timer_stop() 2442 * which should use the async drain function of the 2443 * callout system (see tcp_var.h). 2444 */ 2445 tp->t_fb->tfb_tcp_timer_stop_all(tp); 2446 } 2447 2448 /* free the reassembly queue, if any */ 2449 tcp_reass_flush(tp); 2450 2451 #ifdef TCP_OFFLOAD 2452 /* Disconnect offload device, if any. */ 2453 if (tp->t_flags & TF_TOE) 2454 tcp_offload_detach(tp); 2455 #endif 2456 2457 tcp_free_sackholes(tp); 2458 2459 #ifdef TCPPCAP 2460 /* Free the TCP PCAP queues. */ 2461 tcp_pcap_drain(&(tp->t_inpkts)); 2462 tcp_pcap_drain(&(tp->t_outpkts)); 2463 #endif 2464 2465 /* Allow the CC algorithm to clean up after itself. */ 2466 if (CC_ALGO(tp)->cb_destroy != NULL) 2467 CC_ALGO(tp)->cb_destroy(tp->ccv); 2468 CC_DATA(tp) = NULL; 2469 2470 #ifdef TCP_HHOOK 2471 khelp_destroy_osd(tp->osd); 2472 #endif 2473 #ifdef STATS 2474 stats_blob_destroy(tp->t_stats); 2475 #endif 2476 2477 CC_ALGO(tp) = NULL; 2478 inp->inp_ppcb = NULL; 2479 if (tp->t_timers->tt_draincnt == 0) { 2480 bool released __diagused; 2481 2482 released = tcp_freecb(tp); 2483 KASSERT(!released, ("%s: inp %p should not have been released " 2484 "here", __func__, inp)); 2485 } 2486 } 2487 2488 bool 2489 tcp_freecb(struct tcpcb *tp) 2490 { 2491 struct inpcb *inp = tp->t_inpcb; 2492 struct socket *so = inp->inp_socket; 2493 #ifdef INET6 2494 bool isipv6 = (inp->inp_vflag & INP_IPV6) != 0; 2495 #endif 2496 2497 INP_WLOCK_ASSERT(inp); 2498 MPASS(tp->t_timers->tt_draincnt == 0); 2499 2500 /* We own the last reference on tcpcb, let's free it. */ 2501 #ifdef TCP_BLACKBOX 2502 tcp_log_tcpcbfini(tp); 2503 #endif 2504 TCPSTATES_DEC(tp->t_state); 2505 if (tp->t_fb->tfb_tcp_fb_fini) 2506 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); 2507 2508 /* 2509 * If we got enough samples through the srtt filter, 2510 * save the rtt and rttvar in the routing entry. 2511 * 'Enough' is arbitrarily defined as 4 rtt samples. 2512 * 4 samples is enough for the srtt filter to converge 2513 * to within enough % of the correct value; fewer samples 2514 * and we could save a bogus rtt. The danger is not high 2515 * as tcp quickly recovers from everything. 2516 * XXX: Works very well but needs some more statistics! 2517 * 2518 * XXXRRS: Updating must be after the stack fini() since 2519 * that may be converting some internal representation of 2520 * say srtt etc into the general one used by other stacks. 2521 * Lets also at least protect against the so being NULL 2522 * as RW stated below. 2523 */ 2524 if ((tp->t_rttupdated >= 4) && (so != NULL)) { 2525 struct hc_metrics_lite metrics; 2526 uint32_t ssthresh; 2527 2528 bzero(&metrics, sizeof(metrics)); 2529 /* 2530 * Update the ssthresh always when the conditions below 2531 * are satisfied. This gives us better new start value 2532 * for the congestion avoidance for new connections. 2533 * ssthresh is only set if packet loss occurred on a session. 2534 * 2535 * XXXRW: 'so' may be NULL here, and/or socket buffer may be 2536 * being torn down. Ideally this code would not use 'so'. 2537 */ 2538 ssthresh = tp->snd_ssthresh; 2539 if (ssthresh != 0 && ssthresh < so->so_snd.sb_hiwat / 2) { 2540 /* 2541 * convert the limit from user data bytes to 2542 * packets then to packet data bytes. 2543 */ 2544 ssthresh = (ssthresh + tp->t_maxseg / 2) / tp->t_maxseg; 2545 if (ssthresh < 2) 2546 ssthresh = 2; 2547 ssthresh *= (tp->t_maxseg + 2548 #ifdef INET6 2549 (isipv6 ? sizeof (struct ip6_hdr) + 2550 sizeof (struct tcphdr) : 2551 #endif 2552 sizeof (struct tcpiphdr) 2553 #ifdef INET6 2554 ) 2555 #endif 2556 ); 2557 } else 2558 ssthresh = 0; 2559 metrics.rmx_ssthresh = ssthresh; 2560 2561 metrics.rmx_rtt = tp->t_srtt; 2562 metrics.rmx_rttvar = tp->t_rttvar; 2563 metrics.rmx_cwnd = tp->snd_cwnd; 2564 metrics.rmx_sendpipe = 0; 2565 metrics.rmx_recvpipe = 0; 2566 2567 tcp_hc_update(&inp->inp_inc, &metrics); 2568 } 2569 2570 refcount_release(&tp->t_fb->tfb_refcnt); 2571 uma_zfree(V_tcpcb_zone, tp); 2572 2573 return (in_pcbrele_wlocked(inp)); 2574 } 2575 2576 /* 2577 * Attempt to close a TCP control block, marking it as dropped, and freeing 2578 * the socket if we hold the only reference. 2579 */ 2580 struct tcpcb * 2581 tcp_close(struct tcpcb *tp) 2582 { 2583 struct inpcb *inp = tp->t_inpcb; 2584 struct socket *so; 2585 2586 INP_WLOCK_ASSERT(inp); 2587 2588 #ifdef TCP_OFFLOAD 2589 if (tp->t_state == TCPS_LISTEN) 2590 tcp_offload_listen_stop(tp); 2591 #endif 2592 /* 2593 * This releases the TFO pending counter resource for TFO listen 2594 * sockets as well as passively-created TFO sockets that transition 2595 * from SYN_RECEIVED to CLOSED. 2596 */ 2597 if (tp->t_tfo_pending) { 2598 tcp_fastopen_decrement_counter(tp->t_tfo_pending); 2599 tp->t_tfo_pending = NULL; 2600 } 2601 #ifdef TCPHPTS 2602 tcp_hpts_remove(inp); 2603 #endif 2604 in_pcbdrop(inp); 2605 TCPSTAT_INC(tcps_closed); 2606 if (tp->t_state != TCPS_CLOSED) 2607 tcp_state_change(tp, TCPS_CLOSED); 2608 KASSERT(inp->inp_socket != NULL, ("tcp_close: inp_socket NULL")); 2609 so = inp->inp_socket; 2610 soisdisconnected(so); 2611 if (inp->inp_flags & INP_SOCKREF) { 2612 KASSERT(so->so_state & SS_PROTOREF, 2613 ("tcp_close: !SS_PROTOREF")); 2614 inp->inp_flags &= ~INP_SOCKREF; 2615 INP_WUNLOCK(inp); 2616 SOCK_LOCK(so); 2617 so->so_state &= ~SS_PROTOREF; 2618 sofree(so); 2619 return (NULL); 2620 } 2621 return (tp); 2622 } 2623 2624 void 2625 tcp_drain(void) 2626 { 2627 VNET_ITERATOR_DECL(vnet_iter); 2628 2629 if (!do_tcpdrain) 2630 return; 2631 2632 VNET_LIST_RLOCK_NOSLEEP(); 2633 VNET_FOREACH(vnet_iter) { 2634 CURVNET_SET(vnet_iter); 2635 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, 2636 INPLOOKUP_WLOCKPCB); 2637 struct inpcb *inpb; 2638 struct tcpcb *tcpb; 2639 2640 /* 2641 * Walk the tcpbs, if existing, and flush the reassembly queue, 2642 * if there is one... 2643 * XXX: The "Net/3" implementation doesn't imply that the TCP 2644 * reassembly queue should be flushed, but in a situation 2645 * where we're really low on mbufs, this is potentially 2646 * useful. 2647 */ 2648 while ((inpb = inp_next(&inpi)) != NULL) { 2649 if (inpb->inp_flags & INP_TIMEWAIT) 2650 continue; 2651 if ((tcpb = intotcpcb(inpb)) != NULL) { 2652 tcp_reass_flush(tcpb); 2653 tcp_clean_sackreport(tcpb); 2654 #ifdef TCP_BLACKBOX 2655 tcp_log_drain(tcpb); 2656 #endif 2657 #ifdef TCPPCAP 2658 if (tcp_pcap_aggressive_free) { 2659 /* Free the TCP PCAP queues. */ 2660 tcp_pcap_drain(&(tcpb->t_inpkts)); 2661 tcp_pcap_drain(&(tcpb->t_outpkts)); 2662 } 2663 #endif 2664 } 2665 } 2666 CURVNET_RESTORE(); 2667 } 2668 VNET_LIST_RUNLOCK_NOSLEEP(); 2669 } 2670 2671 /* 2672 * Notify a tcp user of an asynchronous error; 2673 * store error as soft error, but wake up user 2674 * (for now, won't do anything until can select for soft error). 2675 * 2676 * Do not wake up user since there currently is no mechanism for 2677 * reporting soft errors (yet - a kqueue filter may be added). 2678 */ 2679 static struct inpcb * 2680 tcp_notify(struct inpcb *inp, int error) 2681 { 2682 struct tcpcb *tp; 2683 2684 INP_WLOCK_ASSERT(inp); 2685 2686 if ((inp->inp_flags & INP_TIMEWAIT) || 2687 (inp->inp_flags & INP_DROPPED)) 2688 return (inp); 2689 2690 tp = intotcpcb(inp); 2691 KASSERT(tp != NULL, ("tcp_notify: tp == NULL")); 2692 2693 /* 2694 * Ignore some errors if we are hooked up. 2695 * If connection hasn't completed, has retransmitted several times, 2696 * and receives a second error, give up now. This is better 2697 * than waiting a long time to establish a connection that 2698 * can never complete. 2699 */ 2700 if (tp->t_state == TCPS_ESTABLISHED && 2701 (error == EHOSTUNREACH || error == ENETUNREACH || 2702 error == EHOSTDOWN)) { 2703 if (inp->inp_route.ro_nh) { 2704 NH_FREE(inp->inp_route.ro_nh); 2705 inp->inp_route.ro_nh = (struct nhop_object *)NULL; 2706 } 2707 return (inp); 2708 } else if (tp->t_state < TCPS_ESTABLISHED && tp->t_rxtshift > 3 && 2709 tp->t_softerror) { 2710 tp = tcp_drop(tp, error); 2711 if (tp != NULL) 2712 return (inp); 2713 else 2714 return (NULL); 2715 } else { 2716 tp->t_softerror = error; 2717 return (inp); 2718 } 2719 #if 0 2720 wakeup( &so->so_timeo); 2721 sorwakeup(so); 2722 sowwakeup(so); 2723 #endif 2724 } 2725 2726 static int 2727 tcp_pcblist(SYSCTL_HANDLER_ARGS) 2728 { 2729 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, 2730 INPLOOKUP_RLOCKPCB); 2731 struct xinpgen xig; 2732 struct inpcb *inp; 2733 int error; 2734 2735 if (req->newptr != NULL) 2736 return (EPERM); 2737 2738 if (req->oldptr == NULL) { 2739 int n; 2740 2741 n = V_tcbinfo.ipi_count + 2742 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); 2743 n += imax(n / 8, 10); 2744 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xtcpcb); 2745 return (0); 2746 } 2747 2748 if ((error = sysctl_wire_old_buffer(req, 0)) != 0) 2749 return (error); 2750 2751 bzero(&xig, sizeof(xig)); 2752 xig.xig_len = sizeof xig; 2753 xig.xig_count = V_tcbinfo.ipi_count + 2754 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); 2755 xig.xig_gen = V_tcbinfo.ipi_gencnt; 2756 xig.xig_sogen = so_gencnt; 2757 error = SYSCTL_OUT(req, &xig, sizeof xig); 2758 if (error) 2759 return (error); 2760 2761 error = syncache_pcblist(req); 2762 if (error) 2763 return (error); 2764 2765 while ((inp = inp_next(&inpi)) != NULL) { 2766 if (inp->inp_gencnt <= xig.xig_gen) { 2767 int crerr; 2768 2769 /* 2770 * XXX: This use of cr_cansee(), introduced with 2771 * TCP state changes, is not quite right, but for 2772 * now, better than nothing. 2773 */ 2774 if (inp->inp_flags & INP_TIMEWAIT) { 2775 if (intotw(inp) != NULL) 2776 crerr = cr_cansee(req->td->td_ucred, 2777 intotw(inp)->tw_cred); 2778 else 2779 crerr = EINVAL; /* Skip this inp. */ 2780 } else 2781 crerr = cr_canseeinpcb(req->td->td_ucred, inp); 2782 if (crerr == 0) { 2783 struct xtcpcb xt; 2784 2785 tcp_inptoxtp(inp, &xt); 2786 error = SYSCTL_OUT(req, &xt, sizeof xt); 2787 if (error) { 2788 INP_RUNLOCK(inp); 2789 break; 2790 } else 2791 continue; 2792 } 2793 } 2794 } 2795 2796 if (!error) { 2797 /* 2798 * Give the user an updated idea of our state. 2799 * If the generation differs from what we told 2800 * her before, she knows that something happened 2801 * while we were processing this request, and it 2802 * might be necessary to retry. 2803 */ 2804 xig.xig_gen = V_tcbinfo.ipi_gencnt; 2805 xig.xig_sogen = so_gencnt; 2806 xig.xig_count = V_tcbinfo.ipi_count + 2807 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); 2808 error = SYSCTL_OUT(req, &xig, sizeof xig); 2809 } 2810 2811 return (error); 2812 } 2813 2814 SYSCTL_PROC(_net_inet_tcp, TCPCTL_PCBLIST, pcblist, 2815 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_NEEDGIANT, 2816 NULL, 0, tcp_pcblist, "S,xtcpcb", 2817 "List of active TCP connections"); 2818 2819 #ifdef INET 2820 static int 2821 tcp_getcred(SYSCTL_HANDLER_ARGS) 2822 { 2823 struct xucred xuc; 2824 struct sockaddr_in addrs[2]; 2825 struct epoch_tracker et; 2826 struct inpcb *inp; 2827 int error; 2828 2829 error = priv_check(req->td, PRIV_NETINET_GETCRED); 2830 if (error) 2831 return (error); 2832 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 2833 if (error) 2834 return (error); 2835 NET_EPOCH_ENTER(et); 2836 inp = in_pcblookup(&V_tcbinfo, addrs[1].sin_addr, addrs[1].sin_port, 2837 addrs[0].sin_addr, addrs[0].sin_port, INPLOOKUP_RLOCKPCB, NULL); 2838 NET_EPOCH_EXIT(et); 2839 if (inp != NULL) { 2840 if (inp->inp_socket == NULL) 2841 error = ENOENT; 2842 if (error == 0) 2843 error = cr_canseeinpcb(req->td->td_ucred, inp); 2844 if (error == 0) 2845 cru2x(inp->inp_cred, &xuc); 2846 INP_RUNLOCK(inp); 2847 } else 2848 error = ENOENT; 2849 if (error == 0) 2850 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 2851 return (error); 2852 } 2853 2854 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, getcred, 2855 CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_NEEDGIANT, 2856 0, 0, tcp_getcred, "S,xucred", 2857 "Get the xucred of a TCP connection"); 2858 #endif /* INET */ 2859 2860 #ifdef INET6 2861 static int 2862 tcp6_getcred(SYSCTL_HANDLER_ARGS) 2863 { 2864 struct epoch_tracker et; 2865 struct xucred xuc; 2866 struct sockaddr_in6 addrs[2]; 2867 struct inpcb *inp; 2868 int error; 2869 #ifdef INET 2870 int mapped = 0; 2871 #endif 2872 2873 error = priv_check(req->td, PRIV_NETINET_GETCRED); 2874 if (error) 2875 return (error); 2876 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 2877 if (error) 2878 return (error); 2879 if ((error = sa6_embedscope(&addrs[0], V_ip6_use_defzone)) != 0 || 2880 (error = sa6_embedscope(&addrs[1], V_ip6_use_defzone)) != 0) { 2881 return (error); 2882 } 2883 if (IN6_IS_ADDR_V4MAPPED(&addrs[0].sin6_addr)) { 2884 #ifdef INET 2885 if (IN6_IS_ADDR_V4MAPPED(&addrs[1].sin6_addr)) 2886 mapped = 1; 2887 else 2888 #endif 2889 return (EINVAL); 2890 } 2891 2892 NET_EPOCH_ENTER(et); 2893 #ifdef INET 2894 if (mapped == 1) 2895 inp = in_pcblookup(&V_tcbinfo, 2896 *(struct in_addr *)&addrs[1].sin6_addr.s6_addr[12], 2897 addrs[1].sin6_port, 2898 *(struct in_addr *)&addrs[0].sin6_addr.s6_addr[12], 2899 addrs[0].sin6_port, INPLOOKUP_RLOCKPCB, NULL); 2900 else 2901 #endif 2902 inp = in6_pcblookup(&V_tcbinfo, 2903 &addrs[1].sin6_addr, addrs[1].sin6_port, 2904 &addrs[0].sin6_addr, addrs[0].sin6_port, 2905 INPLOOKUP_RLOCKPCB, NULL); 2906 NET_EPOCH_EXIT(et); 2907 if (inp != NULL) { 2908 if (inp->inp_socket == NULL) 2909 error = ENOENT; 2910 if (error == 0) 2911 error = cr_canseeinpcb(req->td->td_ucred, inp); 2912 if (error == 0) 2913 cru2x(inp->inp_cred, &xuc); 2914 INP_RUNLOCK(inp); 2915 } else 2916 error = ENOENT; 2917 if (error == 0) 2918 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 2919 return (error); 2920 } 2921 2922 SYSCTL_PROC(_net_inet6_tcp6, OID_AUTO, getcred, 2923 CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_NEEDGIANT, 2924 0, 0, tcp6_getcred, "S,xucred", 2925 "Get the xucred of a TCP6 connection"); 2926 #endif /* INET6 */ 2927 2928 #ifdef INET 2929 /* Path MTU to try next when a fragmentation-needed message is received. */ 2930 static inline int 2931 tcp_next_pmtu(const struct icmp *icp, const struct ip *ip) 2932 { 2933 int mtu = ntohs(icp->icmp_nextmtu); 2934 2935 /* If no alternative MTU was proposed, try the next smaller one. */ 2936 if (!mtu) 2937 mtu = ip_next_mtu(ntohs(ip->ip_len), 1); 2938 if (mtu < V_tcp_minmss + sizeof(struct tcpiphdr)) 2939 mtu = V_tcp_minmss + sizeof(struct tcpiphdr); 2940 2941 return (mtu); 2942 } 2943 2944 static void 2945 tcp_ctlinput_with_port(int cmd, struct sockaddr *sa, void *vip, uint16_t port) 2946 { 2947 struct ip *ip = vip; 2948 struct tcphdr *th; 2949 struct in_addr faddr; 2950 struct inpcb *inp; 2951 struct tcpcb *tp; 2952 struct inpcb *(*notify)(struct inpcb *, int) = tcp_notify; 2953 struct icmp *icp; 2954 struct in_conninfo inc; 2955 tcp_seq icmp_tcp_seq; 2956 int mtu; 2957 2958 faddr = ((struct sockaddr_in *)sa)->sin_addr; 2959 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY) 2960 return; 2961 2962 if (cmd == PRC_MSGSIZE) 2963 notify = tcp_mtudisc_notify; 2964 else if (V_icmp_may_rst && (cmd == PRC_UNREACH_ADMIN_PROHIB || 2965 cmd == PRC_UNREACH_PORT || cmd == PRC_UNREACH_PROTOCOL || 2966 cmd == PRC_TIMXCEED_INTRANS) && ip) 2967 notify = tcp_drop_syn_sent; 2968 2969 /* 2970 * Hostdead is ugly because it goes linearly through all PCBs. 2971 * XXX: We never get this from ICMP, otherwise it makes an 2972 * excellent DoS attack on machines with many connections. 2973 */ 2974 else if (cmd == PRC_HOSTDEAD) 2975 ip = NULL; 2976 else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0) 2977 return; 2978 2979 if (ip == NULL) { 2980 in_pcbnotifyall(&V_tcbinfo, faddr, inetctlerrmap[cmd], notify); 2981 return; 2982 } 2983 2984 icp = (struct icmp *)((caddr_t)ip - offsetof(struct icmp, icmp_ip)); 2985 th = (struct tcphdr *)((caddr_t)ip + (ip->ip_hl << 2)); 2986 inp = in_pcblookup(&V_tcbinfo, faddr, th->th_dport, ip->ip_src, 2987 th->th_sport, INPLOOKUP_WLOCKPCB, NULL); 2988 if (inp != NULL && PRC_IS_REDIRECT(cmd)) { 2989 /* signal EHOSTDOWN, as it flushes the cached route */ 2990 inp = (*notify)(inp, EHOSTDOWN); 2991 goto out; 2992 } 2993 icmp_tcp_seq = th->th_seq; 2994 if (inp != NULL) { 2995 if (!(inp->inp_flags & INP_TIMEWAIT) && 2996 !(inp->inp_flags & INP_DROPPED) && 2997 !(inp->inp_socket == NULL)) { 2998 tp = intotcpcb(inp); 2999 #ifdef TCP_OFFLOAD 3000 if (tp->t_flags & TF_TOE && cmd == PRC_MSGSIZE) { 3001 /* 3002 * MTU discovery for offloaded connections. Let 3003 * the TOE driver verify seq# and process it. 3004 */ 3005 mtu = tcp_next_pmtu(icp, ip); 3006 tcp_offload_pmtu_update(tp, icmp_tcp_seq, mtu); 3007 goto out; 3008 } 3009 #endif 3010 if (tp->t_port != port) { 3011 goto out; 3012 } 3013 if (SEQ_GEQ(ntohl(icmp_tcp_seq), tp->snd_una) && 3014 SEQ_LT(ntohl(icmp_tcp_seq), tp->snd_max)) { 3015 if (cmd == PRC_MSGSIZE) { 3016 /* 3017 * MTU discovery: we got a needfrag and 3018 * will potentially try a lower MTU. 3019 */ 3020 mtu = tcp_next_pmtu(icp, ip); 3021 3022 /* 3023 * Only process the offered MTU if it 3024 * is smaller than the current one. 3025 */ 3026 if (mtu < tp->t_maxseg + 3027 sizeof(struct tcpiphdr)) { 3028 bzero(&inc, sizeof(inc)); 3029 inc.inc_faddr = faddr; 3030 inc.inc_fibnum = 3031 inp->inp_inc.inc_fibnum; 3032 tcp_hc_updatemtu(&inc, mtu); 3033 inp = tcp_mtudisc(inp, mtu); 3034 } 3035 } else 3036 inp = (*notify)(inp, 3037 inetctlerrmap[cmd]); 3038 } 3039 } 3040 } else { 3041 bzero(&inc, sizeof(inc)); 3042 inc.inc_fport = th->th_dport; 3043 inc.inc_lport = th->th_sport; 3044 inc.inc_faddr = faddr; 3045 inc.inc_laddr = ip->ip_src; 3046 syncache_unreach(&inc, icmp_tcp_seq, port); 3047 } 3048 out: 3049 if (inp != NULL) 3050 INP_WUNLOCK(inp); 3051 } 3052 3053 void 3054 tcp_ctlinput(int cmd, struct sockaddr *sa, void *vip) 3055 { 3056 tcp_ctlinput_with_port(cmd, sa, vip, htons(0)); 3057 } 3058 3059 void 3060 tcp_ctlinput_viaudp(int cmd, struct sockaddr *sa, void *vip, void *unused) 3061 { 3062 /* Its a tunneled TCP over UDP icmp */ 3063 struct ip *outer_ip, *inner_ip; 3064 struct icmp *icmp; 3065 struct udphdr *udp; 3066 struct tcphdr *th, ttemp; 3067 int i_hlen, o_len; 3068 uint16_t port; 3069 3070 inner_ip = (struct ip *)vip; 3071 icmp = (struct icmp *)((caddr_t)inner_ip - 3072 (sizeof(struct icmp) - sizeof(struct ip))); 3073 outer_ip = (struct ip *)((caddr_t)icmp - sizeof(struct ip)); 3074 i_hlen = inner_ip->ip_hl << 2; 3075 o_len = ntohs(outer_ip->ip_len); 3076 if (o_len < 3077 (sizeof(struct ip) + 8 + i_hlen + sizeof(struct udphdr) + offsetof(struct tcphdr, th_ack))) { 3078 /* Not enough data present */ 3079 return; 3080 } 3081 /* Ok lets strip out the inner udphdr header by copying up on top of it the tcp hdr */ 3082 udp = (struct udphdr *)(((caddr_t)inner_ip) + i_hlen); 3083 if (ntohs(udp->uh_sport) != V_tcp_udp_tunneling_port) { 3084 return; 3085 } 3086 port = udp->uh_dport; 3087 th = (struct tcphdr *)(udp + 1); 3088 memcpy(&ttemp, th, sizeof(struct tcphdr)); 3089 memcpy(udp, &ttemp, sizeof(struct tcphdr)); 3090 /* Now adjust down the size of the outer IP header */ 3091 o_len -= sizeof(struct udphdr); 3092 outer_ip->ip_len = htons(o_len); 3093 /* Now call in to the normal handling code */ 3094 tcp_ctlinput_with_port(cmd, sa, vip, port); 3095 } 3096 #endif /* INET */ 3097 3098 #ifdef INET6 3099 static inline int 3100 tcp6_next_pmtu(const struct icmp6_hdr *icmp6) 3101 { 3102 int mtu = ntohl(icmp6->icmp6_mtu); 3103 3104 /* 3105 * If no alternative MTU was proposed, or the proposed MTU was too 3106 * small, set to the min. 3107 */ 3108 if (mtu < IPV6_MMTU) 3109 mtu = IPV6_MMTU - 8; /* XXXNP: what is the adjustment for? */ 3110 return (mtu); 3111 } 3112 3113 static void 3114 tcp6_ctlinput_with_port(int cmd, struct sockaddr *sa, void *d, uint16_t port) 3115 { 3116 struct in6_addr *dst; 3117 struct inpcb *(*notify)(struct inpcb *, int) = tcp_notify; 3118 struct ip6_hdr *ip6; 3119 struct mbuf *m; 3120 struct inpcb *inp; 3121 struct tcpcb *tp; 3122 struct icmp6_hdr *icmp6; 3123 struct ip6ctlparam *ip6cp = NULL; 3124 const struct sockaddr_in6 *sa6_src = NULL; 3125 struct in_conninfo inc; 3126 struct tcp_ports { 3127 uint16_t th_sport; 3128 uint16_t th_dport; 3129 } t_ports; 3130 tcp_seq icmp_tcp_seq; 3131 unsigned int mtu; 3132 unsigned int off; 3133 3134 if (sa->sa_family != AF_INET6 || 3135 sa->sa_len != sizeof(struct sockaddr_in6)) 3136 return; 3137 3138 /* if the parameter is from icmp6, decode it. */ 3139 if (d != NULL) { 3140 ip6cp = (struct ip6ctlparam *)d; 3141 icmp6 = ip6cp->ip6c_icmp6; 3142 m = ip6cp->ip6c_m; 3143 ip6 = ip6cp->ip6c_ip6; 3144 off = ip6cp->ip6c_off; 3145 sa6_src = ip6cp->ip6c_src; 3146 dst = ip6cp->ip6c_finaldst; 3147 } else { 3148 m = NULL; 3149 ip6 = NULL; 3150 off = 0; /* fool gcc */ 3151 sa6_src = &sa6_any; 3152 dst = NULL; 3153 } 3154 3155 if (cmd == PRC_MSGSIZE) 3156 notify = tcp_mtudisc_notify; 3157 else if (V_icmp_may_rst && (cmd == PRC_UNREACH_ADMIN_PROHIB || 3158 cmd == PRC_UNREACH_PORT || cmd == PRC_UNREACH_PROTOCOL || 3159 cmd == PRC_TIMXCEED_INTRANS) && ip6 != NULL) 3160 notify = tcp_drop_syn_sent; 3161 3162 /* 3163 * Hostdead is ugly because it goes linearly through all PCBs. 3164 * XXX: We never get this from ICMP, otherwise it makes an 3165 * excellent DoS attack on machines with many connections. 3166 */ 3167 else if (cmd == PRC_HOSTDEAD) 3168 ip6 = NULL; 3169 else if ((unsigned)cmd >= PRC_NCMDS || inet6ctlerrmap[cmd] == 0) 3170 return; 3171 3172 if (ip6 == NULL) { 3173 in6_pcbnotify(&V_tcbinfo, sa, 0, 3174 (const struct sockaddr *)sa6_src, 3175 0, cmd, NULL, notify); 3176 return; 3177 } 3178 3179 /* Check if we can safely get the ports from the tcp hdr */ 3180 if (m == NULL || 3181 (m->m_pkthdr.len < 3182 (int32_t) (off + sizeof(struct tcp_ports)))) { 3183 return; 3184 } 3185 bzero(&t_ports, sizeof(struct tcp_ports)); 3186 m_copydata(m, off, sizeof(struct tcp_ports), (caddr_t)&t_ports); 3187 inp = in6_pcblookup(&V_tcbinfo, &ip6->ip6_dst, t_ports.th_dport, 3188 &ip6->ip6_src, t_ports.th_sport, INPLOOKUP_WLOCKPCB, NULL); 3189 if (inp != NULL && PRC_IS_REDIRECT(cmd)) { 3190 /* signal EHOSTDOWN, as it flushes the cached route */ 3191 inp = (*notify)(inp, EHOSTDOWN); 3192 goto out; 3193 } 3194 off += sizeof(struct tcp_ports); 3195 if (m->m_pkthdr.len < (int32_t) (off + sizeof(tcp_seq))) { 3196 goto out; 3197 } 3198 m_copydata(m, off, sizeof(tcp_seq), (caddr_t)&icmp_tcp_seq); 3199 if (inp != NULL) { 3200 if (!(inp->inp_flags & INP_TIMEWAIT) && 3201 !(inp->inp_flags & INP_DROPPED) && 3202 !(inp->inp_socket == NULL)) { 3203 tp = intotcpcb(inp); 3204 #ifdef TCP_OFFLOAD 3205 if (tp->t_flags & TF_TOE && cmd == PRC_MSGSIZE) { 3206 /* MTU discovery for offloaded connections. */ 3207 mtu = tcp6_next_pmtu(icmp6); 3208 tcp_offload_pmtu_update(tp, icmp_tcp_seq, mtu); 3209 goto out; 3210 } 3211 #endif 3212 if (tp->t_port != port) { 3213 goto out; 3214 } 3215 if (SEQ_GEQ(ntohl(icmp_tcp_seq), tp->snd_una) && 3216 SEQ_LT(ntohl(icmp_tcp_seq), tp->snd_max)) { 3217 if (cmd == PRC_MSGSIZE) { 3218 /* 3219 * MTU discovery: 3220 * If we got a needfrag set the MTU 3221 * in the route to the suggested new 3222 * value (if given) and then notify. 3223 */ 3224 mtu = tcp6_next_pmtu(icmp6); 3225 3226 bzero(&inc, sizeof(inc)); 3227 inc.inc_fibnum = M_GETFIB(m); 3228 inc.inc_flags |= INC_ISIPV6; 3229 inc.inc6_faddr = *dst; 3230 if (in6_setscope(&inc.inc6_faddr, 3231 m->m_pkthdr.rcvif, NULL)) 3232 goto out; 3233 /* 3234 * Only process the offered MTU if it 3235 * is smaller than the current one. 3236 */ 3237 if (mtu < tp->t_maxseg + 3238 sizeof (struct tcphdr) + 3239 sizeof (struct ip6_hdr)) { 3240 tcp_hc_updatemtu(&inc, mtu); 3241 tcp_mtudisc(inp, mtu); 3242 ICMP6STAT_INC(icp6s_pmtuchg); 3243 } 3244 } else 3245 inp = (*notify)(inp, 3246 inet6ctlerrmap[cmd]); 3247 } 3248 } 3249 } else { 3250 bzero(&inc, sizeof(inc)); 3251 inc.inc_fibnum = M_GETFIB(m); 3252 inc.inc_flags |= INC_ISIPV6; 3253 inc.inc_fport = t_ports.th_dport; 3254 inc.inc_lport = t_ports.th_sport; 3255 inc.inc6_faddr = *dst; 3256 inc.inc6_laddr = ip6->ip6_src; 3257 syncache_unreach(&inc, icmp_tcp_seq, port); 3258 } 3259 out: 3260 if (inp != NULL) 3261 INP_WUNLOCK(inp); 3262 } 3263 3264 void 3265 tcp6_ctlinput(int cmd, struct sockaddr *sa, void *d) 3266 { 3267 tcp6_ctlinput_with_port(cmd, sa, d, htons(0)); 3268 } 3269 3270 void 3271 tcp6_ctlinput_viaudp(int cmd, struct sockaddr *sa, void *d, void *unused) 3272 { 3273 struct ip6ctlparam *ip6cp; 3274 struct mbuf *m; 3275 struct udphdr *udp; 3276 uint16_t port; 3277 3278 ip6cp = (struct ip6ctlparam *)d; 3279 m = m_pulldown(ip6cp->ip6c_m, ip6cp->ip6c_off, sizeof(struct udphdr), NULL); 3280 if (m == NULL) { 3281 return; 3282 } 3283 udp = mtod(m, struct udphdr *); 3284 if (ntohs(udp->uh_sport) != V_tcp_udp_tunneling_port) { 3285 return; 3286 } 3287 port = udp->uh_dport; 3288 m_adj(m, sizeof(struct udphdr)); 3289 if ((m->m_flags & M_PKTHDR) == 0) { 3290 ip6cp->ip6c_m->m_pkthdr.len -= sizeof(struct udphdr); 3291 } 3292 /* Now call in to the normal handling code */ 3293 tcp6_ctlinput_with_port(cmd, sa, d, port); 3294 } 3295 3296 #endif /* INET6 */ 3297 3298 static uint32_t 3299 tcp_keyed_hash(struct in_conninfo *inc, u_char *key, u_int len) 3300 { 3301 SIPHASH_CTX ctx; 3302 uint32_t hash[2]; 3303 3304 KASSERT(len >= SIPHASH_KEY_LENGTH, 3305 ("%s: keylen %u too short ", __func__, len)); 3306 SipHash24_Init(&ctx); 3307 SipHash_SetKey(&ctx, (uint8_t *)key); 3308 SipHash_Update(&ctx, &inc->inc_fport, sizeof(uint16_t)); 3309 SipHash_Update(&ctx, &inc->inc_lport, sizeof(uint16_t)); 3310 switch (inc->inc_flags & INC_ISIPV6) { 3311 #ifdef INET 3312 case 0: 3313 SipHash_Update(&ctx, &inc->inc_faddr, sizeof(struct in_addr)); 3314 SipHash_Update(&ctx, &inc->inc_laddr, sizeof(struct in_addr)); 3315 break; 3316 #endif 3317 #ifdef INET6 3318 case INC_ISIPV6: 3319 SipHash_Update(&ctx, &inc->inc6_faddr, sizeof(struct in6_addr)); 3320 SipHash_Update(&ctx, &inc->inc6_laddr, sizeof(struct in6_addr)); 3321 break; 3322 #endif 3323 } 3324 SipHash_Final((uint8_t *)hash, &ctx); 3325 3326 return (hash[0] ^ hash[1]); 3327 } 3328 3329 uint32_t 3330 tcp_new_ts_offset(struct in_conninfo *inc) 3331 { 3332 struct in_conninfo inc_store, *local_inc; 3333 3334 if (!V_tcp_ts_offset_per_conn) { 3335 memcpy(&inc_store, inc, sizeof(struct in_conninfo)); 3336 inc_store.inc_lport = 0; 3337 inc_store.inc_fport = 0; 3338 local_inc = &inc_store; 3339 } else { 3340 local_inc = inc; 3341 } 3342 return (tcp_keyed_hash(local_inc, V_ts_offset_secret, 3343 sizeof(V_ts_offset_secret))); 3344 } 3345 3346 /* 3347 * Following is where TCP initial sequence number generation occurs. 3348 * 3349 * There are two places where we must use initial sequence numbers: 3350 * 1. In SYN-ACK packets. 3351 * 2. In SYN packets. 3352 * 3353 * All ISNs for SYN-ACK packets are generated by the syncache. See 3354 * tcp_syncache.c for details. 3355 * 3356 * The ISNs in SYN packets must be monotonic; TIME_WAIT recycling 3357 * depends on this property. In addition, these ISNs should be 3358 * unguessable so as to prevent connection hijacking. To satisfy 3359 * the requirements of this situation, the algorithm outlined in 3360 * RFC 1948 is used, with only small modifications. 3361 * 3362 * Implementation details: 3363 * 3364 * Time is based off the system timer, and is corrected so that it 3365 * increases by one megabyte per second. This allows for proper 3366 * recycling on high speed LANs while still leaving over an hour 3367 * before rollover. 3368 * 3369 * As reading the *exact* system time is too expensive to be done 3370 * whenever setting up a TCP connection, we increment the time 3371 * offset in two ways. First, a small random positive increment 3372 * is added to isn_offset for each connection that is set up. 3373 * Second, the function tcp_isn_tick fires once per clock tick 3374 * and increments isn_offset as necessary so that sequence numbers 3375 * are incremented at approximately ISN_BYTES_PER_SECOND. The 3376 * random positive increments serve only to ensure that the same 3377 * exact sequence number is never sent out twice (as could otherwise 3378 * happen when a port is recycled in less than the system tick 3379 * interval.) 3380 * 3381 * net.inet.tcp.isn_reseed_interval controls the number of seconds 3382 * between seeding of isn_secret. This is normally set to zero, 3383 * as reseeding should not be necessary. 3384 * 3385 * Locking of the global variables isn_secret, isn_last_reseed, isn_offset, 3386 * isn_offset_old, and isn_ctx is performed using the ISN lock. In 3387 * general, this means holding an exclusive (write) lock. 3388 */ 3389 3390 #define ISN_BYTES_PER_SECOND 1048576 3391 #define ISN_STATIC_INCREMENT 4096 3392 #define ISN_RANDOM_INCREMENT (4096 - 1) 3393 #define ISN_SECRET_LENGTH SIPHASH_KEY_LENGTH 3394 3395 VNET_DEFINE_STATIC(u_char, isn_secret[ISN_SECRET_LENGTH]); 3396 VNET_DEFINE_STATIC(int, isn_last); 3397 VNET_DEFINE_STATIC(int, isn_last_reseed); 3398 VNET_DEFINE_STATIC(u_int32_t, isn_offset); 3399 VNET_DEFINE_STATIC(u_int32_t, isn_offset_old); 3400 3401 #define V_isn_secret VNET(isn_secret) 3402 #define V_isn_last VNET(isn_last) 3403 #define V_isn_last_reseed VNET(isn_last_reseed) 3404 #define V_isn_offset VNET(isn_offset) 3405 #define V_isn_offset_old VNET(isn_offset_old) 3406 3407 tcp_seq 3408 tcp_new_isn(struct in_conninfo *inc) 3409 { 3410 tcp_seq new_isn; 3411 u_int32_t projected_offset; 3412 3413 ISN_LOCK(); 3414 /* Seed if this is the first use, reseed if requested. */ 3415 if ((V_isn_last_reseed == 0) || ((V_tcp_isn_reseed_interval > 0) && 3416 (((u_int)V_isn_last_reseed + (u_int)V_tcp_isn_reseed_interval*hz) 3417 < (u_int)ticks))) { 3418 arc4rand(&V_isn_secret, sizeof(V_isn_secret), 0); 3419 V_isn_last_reseed = ticks; 3420 } 3421 3422 /* Compute the hash and return the ISN. */ 3423 new_isn = (tcp_seq)tcp_keyed_hash(inc, V_isn_secret, 3424 sizeof(V_isn_secret)); 3425 V_isn_offset += ISN_STATIC_INCREMENT + 3426 (arc4random() & ISN_RANDOM_INCREMENT); 3427 if (ticks != V_isn_last) { 3428 projected_offset = V_isn_offset_old + 3429 ISN_BYTES_PER_SECOND / hz * (ticks - V_isn_last); 3430 if (SEQ_GT(projected_offset, V_isn_offset)) 3431 V_isn_offset = projected_offset; 3432 V_isn_offset_old = V_isn_offset; 3433 V_isn_last = ticks; 3434 } 3435 new_isn += V_isn_offset; 3436 ISN_UNLOCK(); 3437 return (new_isn); 3438 } 3439 3440 /* 3441 * When a specific ICMP unreachable message is received and the 3442 * connection state is SYN-SENT, drop the connection. This behavior 3443 * is controlled by the icmp_may_rst sysctl. 3444 */ 3445 struct inpcb * 3446 tcp_drop_syn_sent(struct inpcb *inp, int errno) 3447 { 3448 struct tcpcb *tp; 3449 3450 NET_EPOCH_ASSERT(); 3451 INP_WLOCK_ASSERT(inp); 3452 3453 if ((inp->inp_flags & INP_TIMEWAIT) || 3454 (inp->inp_flags & INP_DROPPED)) 3455 return (inp); 3456 3457 tp = intotcpcb(inp); 3458 if (tp->t_state != TCPS_SYN_SENT) 3459 return (inp); 3460 3461 if (IS_FASTOPEN(tp->t_flags)) 3462 tcp_fastopen_disable_path(tp); 3463 3464 tp = tcp_drop(tp, errno); 3465 if (tp != NULL) 3466 return (inp); 3467 else 3468 return (NULL); 3469 } 3470 3471 /* 3472 * When `need fragmentation' ICMP is received, update our idea of the MSS 3473 * based on the new value. Also nudge TCP to send something, since we 3474 * know the packet we just sent was dropped. 3475 * This duplicates some code in the tcp_mss() function in tcp_input.c. 3476 */ 3477 static struct inpcb * 3478 tcp_mtudisc_notify(struct inpcb *inp, int error) 3479 { 3480 3481 return (tcp_mtudisc(inp, -1)); 3482 } 3483 3484 static struct inpcb * 3485 tcp_mtudisc(struct inpcb *inp, int mtuoffer) 3486 { 3487 struct tcpcb *tp; 3488 struct socket *so; 3489 3490 INP_WLOCK_ASSERT(inp); 3491 if ((inp->inp_flags & INP_TIMEWAIT) || 3492 (inp->inp_flags & INP_DROPPED)) 3493 return (inp); 3494 3495 tp = intotcpcb(inp); 3496 KASSERT(tp != NULL, ("tcp_mtudisc: tp == NULL")); 3497 3498 tcp_mss_update(tp, -1, mtuoffer, NULL, NULL); 3499 3500 so = inp->inp_socket; 3501 SOCKBUF_LOCK(&so->so_snd); 3502 /* If the mss is larger than the socket buffer, decrease the mss. */ 3503 if (so->so_snd.sb_hiwat < tp->t_maxseg) 3504 tp->t_maxseg = so->so_snd.sb_hiwat; 3505 SOCKBUF_UNLOCK(&so->so_snd); 3506 3507 TCPSTAT_INC(tcps_mturesent); 3508 tp->t_rtttime = 0; 3509 tp->snd_nxt = tp->snd_una; 3510 tcp_free_sackholes(tp); 3511 tp->snd_recover = tp->snd_max; 3512 if (tp->t_flags & TF_SACK_PERMIT) 3513 EXIT_FASTRECOVERY(tp->t_flags); 3514 if (tp->t_fb->tfb_tcp_mtu_chg != NULL) { 3515 /* 3516 * Conceptually the snd_nxt setting 3517 * and freeing sack holes should 3518 * be done by the default stacks 3519 * own tfb_tcp_mtu_chg(). 3520 */ 3521 tp->t_fb->tfb_tcp_mtu_chg(tp); 3522 } 3523 if (tcp_output(tp) < 0) 3524 return (NULL); 3525 else 3526 return (inp); 3527 } 3528 3529 #ifdef INET 3530 /* 3531 * Look-up the routing entry to the peer of this inpcb. If no route 3532 * is found and it cannot be allocated, then return 0. This routine 3533 * is called by TCP routines that access the rmx structure and by 3534 * tcp_mss_update to get the peer/interface MTU. 3535 */ 3536 uint32_t 3537 tcp_maxmtu(struct in_conninfo *inc, struct tcp_ifcap *cap) 3538 { 3539 struct nhop_object *nh; 3540 struct ifnet *ifp; 3541 uint32_t maxmtu = 0; 3542 3543 KASSERT(inc != NULL, ("tcp_maxmtu with NULL in_conninfo pointer")); 3544 3545 if (inc->inc_faddr.s_addr != INADDR_ANY) { 3546 nh = fib4_lookup(inc->inc_fibnum, inc->inc_faddr, 0, NHR_NONE, 0); 3547 if (nh == NULL) 3548 return (0); 3549 3550 ifp = nh->nh_ifp; 3551 maxmtu = nh->nh_mtu; 3552 3553 /* Report additional interface capabilities. */ 3554 if (cap != NULL) { 3555 if (ifp->if_capenable & IFCAP_TSO4 && 3556 ifp->if_hwassist & CSUM_TSO) { 3557 cap->ifcap |= CSUM_TSO; 3558 cap->tsomax = ifp->if_hw_tsomax; 3559 cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount; 3560 cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize; 3561 } 3562 } 3563 } 3564 return (maxmtu); 3565 } 3566 #endif /* INET */ 3567 3568 #ifdef INET6 3569 uint32_t 3570 tcp_maxmtu6(struct in_conninfo *inc, struct tcp_ifcap *cap) 3571 { 3572 struct nhop_object *nh; 3573 struct in6_addr dst6; 3574 uint32_t scopeid; 3575 struct ifnet *ifp; 3576 uint32_t maxmtu = 0; 3577 3578 KASSERT(inc != NULL, ("tcp_maxmtu6 with NULL in_conninfo pointer")); 3579 3580 if (inc->inc_flags & INC_IPV6MINMTU) 3581 return (IPV6_MMTU); 3582 3583 if (!IN6_IS_ADDR_UNSPECIFIED(&inc->inc6_faddr)) { 3584 in6_splitscope(&inc->inc6_faddr, &dst6, &scopeid); 3585 nh = fib6_lookup(inc->inc_fibnum, &dst6, scopeid, NHR_NONE, 0); 3586 if (nh == NULL) 3587 return (0); 3588 3589 ifp = nh->nh_ifp; 3590 maxmtu = nh->nh_mtu; 3591 3592 /* Report additional interface capabilities. */ 3593 if (cap != NULL) { 3594 if (ifp->if_capenable & IFCAP_TSO6 && 3595 ifp->if_hwassist & CSUM_TSO) { 3596 cap->ifcap |= CSUM_TSO; 3597 cap->tsomax = ifp->if_hw_tsomax; 3598 cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount; 3599 cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize; 3600 } 3601 } 3602 } 3603 3604 return (maxmtu); 3605 } 3606 3607 /* 3608 * Handle setsockopt(IPV6_USE_MIN_MTU) by a TCP stack. 3609 * 3610 * XXXGL: we are updating inpcb here with INC_IPV6MINMTU flag. 3611 * The right place to do that is ip6_setpktopt() that has just been 3612 * executed. By the way it just filled ip6po_minmtu for us. 3613 */ 3614 void 3615 tcp6_use_min_mtu(struct tcpcb *tp) 3616 { 3617 struct inpcb *inp = tp->t_inpcb; 3618 3619 INP_WLOCK_ASSERT(inp); 3620 /* 3621 * In case of the IPV6_USE_MIN_MTU socket 3622 * option, the INC_IPV6MINMTU flag to announce 3623 * a corresponding MSS during the initial 3624 * handshake. If the TCP connection is not in 3625 * the front states, just reduce the MSS being 3626 * used. This avoids the sending of TCP 3627 * segments which will be fragmented at the 3628 * IPv6 layer. 3629 */ 3630 inp->inp_inc.inc_flags |= INC_IPV6MINMTU; 3631 if ((tp->t_state >= TCPS_SYN_SENT) && 3632 (inp->inp_inc.inc_flags & INC_ISIPV6)) { 3633 struct ip6_pktopts *opt; 3634 3635 opt = inp->in6p_outputopts; 3636 if (opt != NULL && opt->ip6po_minmtu == IP6PO_MINMTU_ALL && 3637 tp->t_maxseg > TCP6_MSS) 3638 tp->t_maxseg = TCP6_MSS; 3639 } 3640 } 3641 #endif /* INET6 */ 3642 3643 /* 3644 * Calculate effective SMSS per RFC5681 definition for a given TCP 3645 * connection at its current state, taking into account SACK and etc. 3646 */ 3647 u_int 3648 tcp_maxseg(const struct tcpcb *tp) 3649 { 3650 u_int optlen; 3651 3652 if (tp->t_flags & TF_NOOPT) 3653 return (tp->t_maxseg); 3654 3655 /* 3656 * Here we have a simplified code from tcp_addoptions(), 3657 * without a proper loop, and having most of paddings hardcoded. 3658 * We might make mistakes with padding here in some edge cases, 3659 * but this is harmless, since result of tcp_maxseg() is used 3660 * only in cwnd and ssthresh estimations. 3661 */ 3662 if (TCPS_HAVEESTABLISHED(tp->t_state)) { 3663 if (tp->t_flags & TF_RCVD_TSTMP) 3664 optlen = TCPOLEN_TSTAMP_APPA; 3665 else 3666 optlen = 0; 3667 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3668 if (tp->t_flags & TF_SIGNATURE) 3669 optlen += PADTCPOLEN(TCPOLEN_SIGNATURE); 3670 #endif 3671 if ((tp->t_flags & TF_SACK_PERMIT) && tp->rcv_numsacks > 0) { 3672 optlen += TCPOLEN_SACKHDR; 3673 optlen += tp->rcv_numsacks * TCPOLEN_SACK; 3674 optlen = PADTCPOLEN(optlen); 3675 } 3676 } else { 3677 if (tp->t_flags & TF_REQ_TSTMP) 3678 optlen = TCPOLEN_TSTAMP_APPA; 3679 else 3680 optlen = PADTCPOLEN(TCPOLEN_MAXSEG); 3681 if (tp->t_flags & TF_REQ_SCALE) 3682 optlen += PADTCPOLEN(TCPOLEN_WINDOW); 3683 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3684 if (tp->t_flags & TF_SIGNATURE) 3685 optlen += PADTCPOLEN(TCPOLEN_SIGNATURE); 3686 #endif 3687 if (tp->t_flags & TF_SACK_PERMIT) 3688 optlen += PADTCPOLEN(TCPOLEN_SACK_PERMITTED); 3689 } 3690 #undef PAD 3691 optlen = min(optlen, TCP_MAXOLEN); 3692 return (tp->t_maxseg - optlen); 3693 } 3694 3695 3696 u_int 3697 tcp_fixed_maxseg(const struct tcpcb *tp) 3698 { 3699 int optlen; 3700 3701 if (tp->t_flags & TF_NOOPT) 3702 return (tp->t_maxseg); 3703 3704 /* 3705 * Here we have a simplified code from tcp_addoptions(), 3706 * without a proper loop, and having most of paddings hardcoded. 3707 * We only consider fixed options that we would send every 3708 * time I.e. SACK is not considered. This is important 3709 * for cc modules to figure out what the modulo of the 3710 * cwnd should be. 3711 */ 3712 #define PAD(len) ((((len) / 4) + !!((len) % 4)) * 4) 3713 if (TCPS_HAVEESTABLISHED(tp->t_state)) { 3714 if (tp->t_flags & TF_RCVD_TSTMP) 3715 optlen = TCPOLEN_TSTAMP_APPA; 3716 else 3717 optlen = 0; 3718 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3719 if (tp->t_flags & TF_SIGNATURE) 3720 optlen += PAD(TCPOLEN_SIGNATURE); 3721 #endif 3722 } else { 3723 if (tp->t_flags & TF_REQ_TSTMP) 3724 optlen = TCPOLEN_TSTAMP_APPA; 3725 else 3726 optlen = PAD(TCPOLEN_MAXSEG); 3727 if (tp->t_flags & TF_REQ_SCALE) 3728 optlen += PAD(TCPOLEN_WINDOW); 3729 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3730 if (tp->t_flags & TF_SIGNATURE) 3731 optlen += PAD(TCPOLEN_SIGNATURE); 3732 #endif 3733 if (tp->t_flags & TF_SACK_PERMIT) 3734 optlen += PAD(TCPOLEN_SACK_PERMITTED); 3735 } 3736 #undef PAD 3737 optlen = min(optlen, TCP_MAXOLEN); 3738 return (tp->t_maxseg - optlen); 3739 } 3740 3741 3742 3743 static int 3744 sysctl_drop(SYSCTL_HANDLER_ARGS) 3745 { 3746 /* addrs[0] is a foreign socket, addrs[1] is a local one. */ 3747 struct sockaddr_storage addrs[2]; 3748 struct inpcb *inp; 3749 struct tcpcb *tp; 3750 struct tcptw *tw; 3751 struct sockaddr_in *fin, *lin; 3752 struct epoch_tracker et; 3753 #ifdef INET6 3754 struct sockaddr_in6 *fin6, *lin6; 3755 #endif 3756 int error; 3757 3758 inp = NULL; 3759 fin = lin = NULL; 3760 #ifdef INET6 3761 fin6 = lin6 = NULL; 3762 #endif 3763 error = 0; 3764 3765 if (req->oldptr != NULL || req->oldlen != 0) 3766 return (EINVAL); 3767 if (req->newptr == NULL) 3768 return (EPERM); 3769 if (req->newlen < sizeof(addrs)) 3770 return (ENOMEM); 3771 error = SYSCTL_IN(req, &addrs, sizeof(addrs)); 3772 if (error) 3773 return (error); 3774 3775 switch (addrs[0].ss_family) { 3776 #ifdef INET6 3777 case AF_INET6: 3778 fin6 = (struct sockaddr_in6 *)&addrs[0]; 3779 lin6 = (struct sockaddr_in6 *)&addrs[1]; 3780 if (fin6->sin6_len != sizeof(struct sockaddr_in6) || 3781 lin6->sin6_len != sizeof(struct sockaddr_in6)) 3782 return (EINVAL); 3783 if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr)) { 3784 if (!IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr)) 3785 return (EINVAL); 3786 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[0]); 3787 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[1]); 3788 fin = (struct sockaddr_in *)&addrs[0]; 3789 lin = (struct sockaddr_in *)&addrs[1]; 3790 break; 3791 } 3792 error = sa6_embedscope(fin6, V_ip6_use_defzone); 3793 if (error) 3794 return (error); 3795 error = sa6_embedscope(lin6, V_ip6_use_defzone); 3796 if (error) 3797 return (error); 3798 break; 3799 #endif 3800 #ifdef INET 3801 case AF_INET: 3802 fin = (struct sockaddr_in *)&addrs[0]; 3803 lin = (struct sockaddr_in *)&addrs[1]; 3804 if (fin->sin_len != sizeof(struct sockaddr_in) || 3805 lin->sin_len != sizeof(struct sockaddr_in)) 3806 return (EINVAL); 3807 break; 3808 #endif 3809 default: 3810 return (EINVAL); 3811 } 3812 NET_EPOCH_ENTER(et); 3813 switch (addrs[0].ss_family) { 3814 #ifdef INET6 3815 case AF_INET6: 3816 inp = in6_pcblookup(&V_tcbinfo, &fin6->sin6_addr, 3817 fin6->sin6_port, &lin6->sin6_addr, lin6->sin6_port, 3818 INPLOOKUP_WLOCKPCB, NULL); 3819 break; 3820 #endif 3821 #ifdef INET 3822 case AF_INET: 3823 inp = in_pcblookup(&V_tcbinfo, fin->sin_addr, fin->sin_port, 3824 lin->sin_addr, lin->sin_port, INPLOOKUP_WLOCKPCB, NULL); 3825 break; 3826 #endif 3827 } 3828 if (inp != NULL) { 3829 if (inp->inp_flags & INP_TIMEWAIT) { 3830 /* 3831 * XXXRW: There currently exists a state where an 3832 * inpcb is present, but its timewait state has been 3833 * discarded. For now, don't allow dropping of this 3834 * type of inpcb. 3835 */ 3836 tw = intotw(inp); 3837 if (tw != NULL) 3838 tcp_twclose(tw, 0); 3839 else 3840 INP_WUNLOCK(inp); 3841 } else if ((inp->inp_flags & INP_DROPPED) == 0 && 3842 !SOLISTENING(inp->inp_socket)) { 3843 tp = intotcpcb(inp); 3844 tp = tcp_drop(tp, ECONNABORTED); 3845 if (tp != NULL) 3846 INP_WUNLOCK(inp); 3847 } else 3848 INP_WUNLOCK(inp); 3849 } else 3850 error = ESRCH; 3851 NET_EPOCH_EXIT(et); 3852 return (error); 3853 } 3854 3855 SYSCTL_PROC(_net_inet_tcp, TCPCTL_DROP, drop, 3856 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | 3857 CTLFLAG_NEEDGIANT, NULL, 0, sysctl_drop, "", 3858 "Drop TCP connection"); 3859 3860 #ifdef KERN_TLS 3861 static int 3862 sysctl_switch_tls(SYSCTL_HANDLER_ARGS) 3863 { 3864 /* addrs[0] is a foreign socket, addrs[1] is a local one. */ 3865 struct sockaddr_storage addrs[2]; 3866 struct inpcb *inp; 3867 struct sockaddr_in *fin, *lin; 3868 struct epoch_tracker et; 3869 #ifdef INET6 3870 struct sockaddr_in6 *fin6, *lin6; 3871 #endif 3872 int error; 3873 3874 inp = NULL; 3875 fin = lin = NULL; 3876 #ifdef INET6 3877 fin6 = lin6 = NULL; 3878 #endif 3879 error = 0; 3880 3881 if (req->oldptr != NULL || req->oldlen != 0) 3882 return (EINVAL); 3883 if (req->newptr == NULL) 3884 return (EPERM); 3885 if (req->newlen < sizeof(addrs)) 3886 return (ENOMEM); 3887 error = SYSCTL_IN(req, &addrs, sizeof(addrs)); 3888 if (error) 3889 return (error); 3890 3891 switch (addrs[0].ss_family) { 3892 #ifdef INET6 3893 case AF_INET6: 3894 fin6 = (struct sockaddr_in6 *)&addrs[0]; 3895 lin6 = (struct sockaddr_in6 *)&addrs[1]; 3896 if (fin6->sin6_len != sizeof(struct sockaddr_in6) || 3897 lin6->sin6_len != sizeof(struct sockaddr_in6)) 3898 return (EINVAL); 3899 if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr)) { 3900 if (!IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr)) 3901 return (EINVAL); 3902 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[0]); 3903 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[1]); 3904 fin = (struct sockaddr_in *)&addrs[0]; 3905 lin = (struct sockaddr_in *)&addrs[1]; 3906 break; 3907 } 3908 error = sa6_embedscope(fin6, V_ip6_use_defzone); 3909 if (error) 3910 return (error); 3911 error = sa6_embedscope(lin6, V_ip6_use_defzone); 3912 if (error) 3913 return (error); 3914 break; 3915 #endif 3916 #ifdef INET 3917 case AF_INET: 3918 fin = (struct sockaddr_in *)&addrs[0]; 3919 lin = (struct sockaddr_in *)&addrs[1]; 3920 if (fin->sin_len != sizeof(struct sockaddr_in) || 3921 lin->sin_len != sizeof(struct sockaddr_in)) 3922 return (EINVAL); 3923 break; 3924 #endif 3925 default: 3926 return (EINVAL); 3927 } 3928 NET_EPOCH_ENTER(et); 3929 switch (addrs[0].ss_family) { 3930 #ifdef INET6 3931 case AF_INET6: 3932 inp = in6_pcblookup(&V_tcbinfo, &fin6->sin6_addr, 3933 fin6->sin6_port, &lin6->sin6_addr, lin6->sin6_port, 3934 INPLOOKUP_WLOCKPCB, NULL); 3935 break; 3936 #endif 3937 #ifdef INET 3938 case AF_INET: 3939 inp = in_pcblookup(&V_tcbinfo, fin->sin_addr, fin->sin_port, 3940 lin->sin_addr, lin->sin_port, INPLOOKUP_WLOCKPCB, NULL); 3941 break; 3942 #endif 3943 } 3944 NET_EPOCH_EXIT(et); 3945 if (inp != NULL) { 3946 if ((inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) != 0 || 3947 inp->inp_socket == NULL) { 3948 error = ECONNRESET; 3949 INP_WUNLOCK(inp); 3950 } else { 3951 struct socket *so; 3952 3953 so = inp->inp_socket; 3954 soref(so); 3955 error = ktls_set_tx_mode(so, 3956 arg2 == 0 ? TCP_TLS_MODE_SW : TCP_TLS_MODE_IFNET); 3957 INP_WUNLOCK(inp); 3958 sorele(so); 3959 } 3960 } else 3961 error = ESRCH; 3962 return (error); 3963 } 3964 3965 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, switch_to_sw_tls, 3966 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | 3967 CTLFLAG_NEEDGIANT, NULL, 0, sysctl_switch_tls, "", 3968 "Switch TCP connection to SW TLS"); 3969 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, switch_to_ifnet_tls, 3970 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | 3971 CTLFLAG_NEEDGIANT, NULL, 1, sysctl_switch_tls, "", 3972 "Switch TCP connection to ifnet TLS"); 3973 #endif 3974 3975 /* 3976 * Generate a standardized TCP log line for use throughout the 3977 * tcp subsystem. Memory allocation is done with M_NOWAIT to 3978 * allow use in the interrupt context. 3979 * 3980 * NB: The caller MUST free(s, M_TCPLOG) the returned string. 3981 * NB: The function may return NULL if memory allocation failed. 3982 * 3983 * Due to header inclusion and ordering limitations the struct ip 3984 * and ip6_hdr pointers have to be passed as void pointers. 3985 */ 3986 char * 3987 tcp_log_vain(struct in_conninfo *inc, struct tcphdr *th, void *ip4hdr, 3988 const void *ip6hdr) 3989 { 3990 3991 /* Is logging enabled? */ 3992 if (V_tcp_log_in_vain == 0) 3993 return (NULL); 3994 3995 return (tcp_log_addr(inc, th, ip4hdr, ip6hdr)); 3996 } 3997 3998 char * 3999 tcp_log_addrs(struct in_conninfo *inc, struct tcphdr *th, void *ip4hdr, 4000 const void *ip6hdr) 4001 { 4002 4003 /* Is logging enabled? */ 4004 if (tcp_log_debug == 0) 4005 return (NULL); 4006 4007 return (tcp_log_addr(inc, th, ip4hdr, ip6hdr)); 4008 } 4009 4010 static char * 4011 tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th, void *ip4hdr, 4012 const void *ip6hdr) 4013 { 4014 char *s, *sp; 4015 size_t size; 4016 struct ip *ip; 4017 #ifdef INET6 4018 const struct ip6_hdr *ip6; 4019 4020 ip6 = (const struct ip6_hdr *)ip6hdr; 4021 #endif /* INET6 */ 4022 ip = (struct ip *)ip4hdr; 4023 4024 /* 4025 * The log line looks like this: 4026 * "TCP: [1.2.3.4]:50332 to [1.2.3.4]:80 tcpflags 0x2<SYN>" 4027 */ 4028 size = sizeof("TCP: []:12345 to []:12345 tcpflags 0x2<>") + 4029 sizeof(PRINT_TH_FLAGS) + 1 + 4030 #ifdef INET6 4031 2 * INET6_ADDRSTRLEN; 4032 #else 4033 2 * INET_ADDRSTRLEN; 4034 #endif /* INET6 */ 4035 4036 s = malloc(size, M_TCPLOG, M_ZERO|M_NOWAIT); 4037 if (s == NULL) 4038 return (NULL); 4039 4040 strcat(s, "TCP: ["); 4041 sp = s + strlen(s); 4042 4043 if (inc && ((inc->inc_flags & INC_ISIPV6) == 0)) { 4044 inet_ntoa_r(inc->inc_faddr, sp); 4045 sp = s + strlen(s); 4046 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport)); 4047 sp = s + strlen(s); 4048 inet_ntoa_r(inc->inc_laddr, sp); 4049 sp = s + strlen(s); 4050 sprintf(sp, "]:%i", ntohs(inc->inc_lport)); 4051 #ifdef INET6 4052 } else if (inc) { 4053 ip6_sprintf(sp, &inc->inc6_faddr); 4054 sp = s + strlen(s); 4055 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport)); 4056 sp = s + strlen(s); 4057 ip6_sprintf(sp, &inc->inc6_laddr); 4058 sp = s + strlen(s); 4059 sprintf(sp, "]:%i", ntohs(inc->inc_lport)); 4060 } else if (ip6 && th) { 4061 ip6_sprintf(sp, &ip6->ip6_src); 4062 sp = s + strlen(s); 4063 sprintf(sp, "]:%i to [", ntohs(th->th_sport)); 4064 sp = s + strlen(s); 4065 ip6_sprintf(sp, &ip6->ip6_dst); 4066 sp = s + strlen(s); 4067 sprintf(sp, "]:%i", ntohs(th->th_dport)); 4068 #endif /* INET6 */ 4069 #ifdef INET 4070 } else if (ip && th) { 4071 inet_ntoa_r(ip->ip_src, sp); 4072 sp = s + strlen(s); 4073 sprintf(sp, "]:%i to [", ntohs(th->th_sport)); 4074 sp = s + strlen(s); 4075 inet_ntoa_r(ip->ip_dst, sp); 4076 sp = s + strlen(s); 4077 sprintf(sp, "]:%i", ntohs(th->th_dport)); 4078 #endif /* INET */ 4079 } else { 4080 free(s, M_TCPLOG); 4081 return (NULL); 4082 } 4083 sp = s + strlen(s); 4084 if (th) 4085 sprintf(sp, " tcpflags 0x%b", th->th_flags, PRINT_TH_FLAGS); 4086 if (*(s + size - 1) != '\0') 4087 panic("%s: string too long", __func__); 4088 return (s); 4089 } 4090 4091 /* 4092 * A subroutine which makes it easy to track TCP state changes with DTrace. 4093 * This function shouldn't be called for t_state initializations that don't 4094 * correspond to actual TCP state transitions. 4095 */ 4096 void 4097 tcp_state_change(struct tcpcb *tp, int newstate) 4098 { 4099 #if defined(KDTRACE_HOOKS) 4100 int pstate = tp->t_state; 4101 #endif 4102 4103 TCPSTATES_DEC(tp->t_state); 4104 TCPSTATES_INC(newstate); 4105 tp->t_state = newstate; 4106 TCP_PROBE6(state__change, NULL, tp, NULL, tp, NULL, pstate); 4107 } 4108 4109 /* 4110 * Create an external-format (``xtcpcb'') structure using the information in 4111 * the kernel-format tcpcb structure pointed to by tp. This is done to 4112 * reduce the spew of irrelevant information over this interface, to isolate 4113 * user code from changes in the kernel structure, and potentially to provide 4114 * information-hiding if we decide that some of this information should be 4115 * hidden from users. 4116 */ 4117 void 4118 tcp_inptoxtp(const struct inpcb *inp, struct xtcpcb *xt) 4119 { 4120 struct tcpcb *tp = intotcpcb(inp); 4121 struct tcptw *tw = intotw(inp); 4122 sbintime_t now; 4123 4124 bzero(xt, sizeof(*xt)); 4125 if (inp->inp_flags & INP_TIMEWAIT) { 4126 xt->t_state = TCPS_TIME_WAIT; 4127 xt->xt_encaps_port = tw->t_port; 4128 } else { 4129 xt->t_state = tp->t_state; 4130 xt->t_logstate = tp->t_logstate; 4131 xt->t_flags = tp->t_flags; 4132 xt->t_sndzerowin = tp->t_sndzerowin; 4133 xt->t_sndrexmitpack = tp->t_sndrexmitpack; 4134 xt->t_rcvoopack = tp->t_rcvoopack; 4135 xt->t_rcv_wnd = tp->rcv_wnd; 4136 xt->t_snd_wnd = tp->snd_wnd; 4137 xt->t_snd_cwnd = tp->snd_cwnd; 4138 xt->t_snd_ssthresh = tp->snd_ssthresh; 4139 xt->t_dsack_bytes = tp->t_dsack_bytes; 4140 xt->t_dsack_tlp_bytes = tp->t_dsack_tlp_bytes; 4141 xt->t_dsack_pack = tp->t_dsack_pack; 4142 xt->t_maxseg = tp->t_maxseg; 4143 xt->xt_ecn = (tp->t_flags2 & TF2_ECN_PERMIT) ? 1 : 0 + 4144 (tp->t_flags2 & TF2_ACE_PERMIT) ? 2 : 0; 4145 4146 now = getsbinuptime(); 4147 #define COPYTIMER(ttt) do { \ 4148 if (callout_active(&tp->t_timers->ttt)) \ 4149 xt->ttt = (tp->t_timers->ttt.c_time - now) / \ 4150 SBT_1MS; \ 4151 else \ 4152 xt->ttt = 0; \ 4153 } while (0) 4154 COPYTIMER(tt_delack); 4155 COPYTIMER(tt_rexmt); 4156 COPYTIMER(tt_persist); 4157 COPYTIMER(tt_keep); 4158 COPYTIMER(tt_2msl); 4159 #undef COPYTIMER 4160 xt->t_rcvtime = 1000 * (ticks - tp->t_rcvtime) / hz; 4161 4162 xt->xt_encaps_port = tp->t_port; 4163 bcopy(tp->t_fb->tfb_tcp_block_name, xt->xt_stack, 4164 TCP_FUNCTION_NAME_LEN_MAX); 4165 bcopy(CC_ALGO(tp)->name, xt->xt_cc, 4166 TCP_CA_NAME_MAX); 4167 #ifdef TCP_BLACKBOX 4168 (void)tcp_log_get_id(tp, xt->xt_logid); 4169 #endif 4170 } 4171 4172 xt->xt_len = sizeof(struct xtcpcb); 4173 in_pcbtoxinpcb(inp, &xt->xt_inp); 4174 if (inp->inp_socket == NULL) 4175 xt->xt_inp.xi_socket.xso_protocol = IPPROTO_TCP; 4176 } 4177 4178 void 4179 tcp_log_end_status(struct tcpcb *tp, uint8_t status) 4180 { 4181 uint32_t bit, i; 4182 4183 if ((tp == NULL) || 4184 (status > TCP_EI_STATUS_MAX_VALUE) || 4185 (status == 0)) { 4186 /* Invalid */ 4187 return; 4188 } 4189 if (status > (sizeof(uint32_t) * 8)) { 4190 /* Should this be a KASSERT? */ 4191 return; 4192 } 4193 bit = 1U << (status - 1); 4194 if (bit & tp->t_end_info_status) { 4195 /* already logged */ 4196 return; 4197 } 4198 for (i = 0; i < TCP_END_BYTE_INFO; i++) { 4199 if (tp->t_end_info_bytes[i] == TCP_EI_EMPTY_SLOT) { 4200 tp->t_end_info_bytes[i] = status; 4201 tp->t_end_info_status |= bit; 4202 break; 4203 } 4204 } 4205 } 4206 4207 int 4208 tcp_can_enable_pacing(void) 4209 { 4210 4211 if ((tcp_pacing_limit == -1) || 4212 (tcp_pacing_limit > number_of_tcp_connections_pacing)) { 4213 atomic_fetchadd_int(&number_of_tcp_connections_pacing, 1); 4214 shadow_num_connections = number_of_tcp_connections_pacing; 4215 return (1); 4216 } else { 4217 return (0); 4218 } 4219 } 4220 4221 static uint8_t tcp_pacing_warning = 0; 4222 4223 void 4224 tcp_decrement_paced_conn(void) 4225 { 4226 uint32_t ret; 4227 4228 ret = atomic_fetchadd_int(&number_of_tcp_connections_pacing, -1); 4229 shadow_num_connections = number_of_tcp_connections_pacing; 4230 KASSERT(ret != 0, ("tcp_paced_connection_exits -1 would cause wrap?")); 4231 if (ret == 0) { 4232 if (tcp_pacing_limit != -1) { 4233 printf("Warning all pacing is now disabled, count decrements invalidly!\n"); 4234 tcp_pacing_limit = 0; 4235 } else if (tcp_pacing_warning == 0) { 4236 printf("Warning pacing count is invalid, invalid decrement\n"); 4237 tcp_pacing_warning = 1; 4238 } 4239 } 4240 } 4241