1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)tcp_subr.c 8.2 (Berkeley) 5/24/95 32 */ 33 34 #include <sys/cdefs.h> 35 __FBSDID("$FreeBSD$"); 36 37 #include "opt_inet.h" 38 #include "opt_inet6.h" 39 #include "opt_ipsec.h" 40 #include "opt_kern_tls.h" 41 #include "opt_tcpdebug.h" 42 43 #include <sys/param.h> 44 #include <sys/systm.h> 45 #include <sys/arb.h> 46 #include <sys/callout.h> 47 #include <sys/eventhandler.h> 48 #ifdef TCP_HHOOK 49 #include <sys/hhook.h> 50 #endif 51 #include <sys/kernel.h> 52 #ifdef TCP_HHOOK 53 #include <sys/khelp.h> 54 #endif 55 #ifdef KERN_TLS 56 #include <sys/ktls.h> 57 #endif 58 #include <sys/qmath.h> 59 #include <sys/stats.h> 60 #include <sys/sysctl.h> 61 #include <sys/jail.h> 62 #include <sys/malloc.h> 63 #include <sys/refcount.h> 64 #include <sys/mbuf.h> 65 #ifdef INET6 66 #include <sys/domain.h> 67 #endif 68 #include <sys/priv.h> 69 #include <sys/proc.h> 70 #include <sys/sdt.h> 71 #include <sys/socket.h> 72 #include <sys/socketvar.h> 73 #include <sys/protosw.h> 74 #include <sys/random.h> 75 76 #include <vm/uma.h> 77 78 #include <net/route.h> 79 #include <net/route/nhop.h> 80 #include <net/if.h> 81 #include <net/if_var.h> 82 #include <net/vnet.h> 83 84 #include <netinet/in.h> 85 #include <netinet/in_fib.h> 86 #include <netinet/in_kdtrace.h> 87 #include <netinet/in_pcb.h> 88 #include <netinet/in_systm.h> 89 #include <netinet/in_var.h> 90 #include <netinet/ip.h> 91 #include <netinet/ip_icmp.h> 92 #include <netinet/ip_var.h> 93 #ifdef INET6 94 #include <netinet/icmp6.h> 95 #include <netinet/ip6.h> 96 #include <netinet6/in6_fib.h> 97 #include <netinet6/in6_pcb.h> 98 #include <netinet6/ip6_var.h> 99 #include <netinet6/scope6_var.h> 100 #include <netinet6/nd6.h> 101 #endif 102 103 #include <netinet/tcp.h> 104 #ifdef INVARIANTS 105 #define TCPSTATES 106 #endif 107 #include <netinet/tcp_fsm.h> 108 #include <netinet/tcp_seq.h> 109 #include <netinet/tcp_timer.h> 110 #include <netinet/tcp_var.h> 111 #include <netinet/tcp_log_buf.h> 112 #include <netinet/tcp_syncache.h> 113 #include <netinet/tcp_hpts.h> 114 #include <netinet/cc/cc.h> 115 #ifdef INET6 116 #include <netinet6/tcp6_var.h> 117 #endif 118 #include <netinet/tcpip.h> 119 #include <netinet/tcp_fastopen.h> 120 #ifdef TCPPCAP 121 #include <netinet/tcp_pcap.h> 122 #endif 123 #ifdef TCPDEBUG 124 #include <netinet/tcp_debug.h> 125 #endif 126 #ifdef INET6 127 #include <netinet6/ip6protosw.h> 128 #endif 129 #ifdef TCP_OFFLOAD 130 #include <netinet/tcp_offload.h> 131 #endif 132 #include <netinet/udp.h> 133 #include <netinet/udp_var.h> 134 135 #include <netipsec/ipsec_support.h> 136 137 #include <machine/in_cksum.h> 138 #include <crypto/siphash/siphash.h> 139 140 #include <security/mac/mac_framework.h> 141 142 VNET_DEFINE(int, tcp_mssdflt) = TCP_MSS; 143 #ifdef INET6 144 VNET_DEFINE(int, tcp_v6mssdflt) = TCP6_MSS; 145 #endif 146 147 #ifdef NETFLIX_EXP_DETECTION 148 /* Sack attack detection thresholds and such */ 149 SYSCTL_NODE(_net_inet_tcp, OID_AUTO, sack_attack, 150 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 151 "Sack Attack detection thresholds"); 152 int32_t tcp_force_detection = 0; 153 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, force_detection, 154 CTLFLAG_RW, 155 &tcp_force_detection, 0, 156 "Do we force detection even if the INP has it off?"); 157 int32_t tcp_sack_to_ack_thresh = 700; /* 70 % */ 158 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, sack_to_ack_thresh, 159 CTLFLAG_RW, 160 &tcp_sack_to_ack_thresh, 700, 161 "Percentage of sacks to acks we must see above (10.1 percent is 101)?"); 162 int32_t tcp_sack_to_move_thresh = 600; /* 60 % */ 163 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, move_thresh, 164 CTLFLAG_RW, 165 &tcp_sack_to_move_thresh, 600, 166 "Percentage of sack moves we must see above (10.1 percent is 101)"); 167 int32_t tcp_restoral_thresh = 650; /* 65 % (sack:2:ack -5%) */ 168 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, restore_thresh, 169 CTLFLAG_RW, 170 &tcp_restoral_thresh, 550, 171 "Percentage of sack to ack percentage we must see below to restore(10.1 percent is 101)"); 172 int32_t tcp_sad_decay_val = 800; 173 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, decay_per, 174 CTLFLAG_RW, 175 &tcp_sad_decay_val, 800, 176 "The decay percentage (10.1 percent equals 101 )"); 177 int32_t tcp_map_minimum = 500; 178 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, nummaps, 179 CTLFLAG_RW, 180 &tcp_map_minimum, 500, 181 "Number of Map enteries before we start detection"); 182 int32_t tcp_attack_on_turns_on_logging = 0; 183 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, attacks_logged, 184 CTLFLAG_RW, 185 &tcp_attack_on_turns_on_logging, 0, 186 "When we have a positive hit on attack, do we turn on logging?"); 187 int32_t tcp_sad_pacing_interval = 2000; 188 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, sad_pacing_int, 189 CTLFLAG_RW, 190 &tcp_sad_pacing_interval, 2000, 191 "What is the minimum pacing interval for a classified attacker?"); 192 193 int32_t tcp_sad_low_pps = 100; 194 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, sad_low_pps, 195 CTLFLAG_RW, 196 &tcp_sad_low_pps, 100, 197 "What is the input pps that below which we do not decay?"); 198 #endif 199 uint32_t tcp_ack_war_time_window = 1000; 200 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, ack_war_timewindow, 201 CTLFLAG_RW, 202 &tcp_ack_war_time_window, 1000, 203 "If the tcp_stack does ack-war prevention how many milliseconds are in its time window?"); 204 uint32_t tcp_ack_war_cnt = 5; 205 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, ack_war_cnt, 206 CTLFLAG_RW, 207 &tcp_ack_war_cnt, 5, 208 "If the tcp_stack does ack-war prevention how many acks can be sent in its time window?"); 209 210 struct rwlock tcp_function_lock; 211 212 static int 213 sysctl_net_inet_tcp_mss_check(SYSCTL_HANDLER_ARGS) 214 { 215 int error, new; 216 217 new = V_tcp_mssdflt; 218 error = sysctl_handle_int(oidp, &new, 0, req); 219 if (error == 0 && req->newptr) { 220 if (new < TCP_MINMSS) 221 error = EINVAL; 222 else 223 V_tcp_mssdflt = new; 224 } 225 return (error); 226 } 227 228 SYSCTL_PROC(_net_inet_tcp, TCPCTL_MSSDFLT, mssdflt, 229 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 230 &VNET_NAME(tcp_mssdflt), 0, &sysctl_net_inet_tcp_mss_check, "I", 231 "Default TCP Maximum Segment Size"); 232 233 #ifdef INET6 234 static int 235 sysctl_net_inet_tcp_mss_v6_check(SYSCTL_HANDLER_ARGS) 236 { 237 int error, new; 238 239 new = V_tcp_v6mssdflt; 240 error = sysctl_handle_int(oidp, &new, 0, req); 241 if (error == 0 && req->newptr) { 242 if (new < TCP_MINMSS) 243 error = EINVAL; 244 else 245 V_tcp_v6mssdflt = new; 246 } 247 return (error); 248 } 249 250 SYSCTL_PROC(_net_inet_tcp, TCPCTL_V6MSSDFLT, v6mssdflt, 251 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 252 &VNET_NAME(tcp_v6mssdflt), 0, &sysctl_net_inet_tcp_mss_v6_check, "I", 253 "Default TCP Maximum Segment Size for IPv6"); 254 #endif /* INET6 */ 255 256 /* 257 * Minimum MSS we accept and use. This prevents DoS attacks where 258 * we are forced to a ridiculous low MSS like 20 and send hundreds 259 * of packets instead of one. The effect scales with the available 260 * bandwidth and quickly saturates the CPU and network interface 261 * with packet generation and sending. Set to zero to disable MINMSS 262 * checking. This setting prevents us from sending too small packets. 263 */ 264 VNET_DEFINE(int, tcp_minmss) = TCP_MINMSS; 265 SYSCTL_INT(_net_inet_tcp, OID_AUTO, minmss, CTLFLAG_VNET | CTLFLAG_RW, 266 &VNET_NAME(tcp_minmss), 0, 267 "Minimum TCP Maximum Segment Size"); 268 269 VNET_DEFINE(int, tcp_do_rfc1323) = 1; 270 SYSCTL_INT(_net_inet_tcp, TCPCTL_DO_RFC1323, rfc1323, CTLFLAG_VNET | CTLFLAG_RW, 271 &VNET_NAME(tcp_do_rfc1323), 0, 272 "Enable rfc1323 (high performance TCP) extensions"); 273 274 /* 275 * As of June 2021, several TCP stacks violate RFC 7323 from September 2014. 276 * Some stacks negotiate TS, but never send them after connection setup. Some 277 * stacks negotiate TS, but don't send them when sending keep-alive segments. 278 * These include modern widely deployed TCP stacks. 279 * Therefore tolerating violations for now... 280 */ 281 VNET_DEFINE(int, tcp_tolerate_missing_ts) = 1; 282 SYSCTL_INT(_net_inet_tcp, OID_AUTO, tolerate_missing_ts, CTLFLAG_VNET | CTLFLAG_RW, 283 &VNET_NAME(tcp_tolerate_missing_ts), 0, 284 "Tolerate missing TCP timestamps"); 285 286 VNET_DEFINE(int, tcp_ts_offset_per_conn) = 1; 287 SYSCTL_INT(_net_inet_tcp, OID_AUTO, ts_offset_per_conn, CTLFLAG_VNET | CTLFLAG_RW, 288 &VNET_NAME(tcp_ts_offset_per_conn), 0, 289 "Initialize TCP timestamps per connection instead of per host pair"); 290 291 /* How many connections are pacing */ 292 static volatile uint32_t number_of_tcp_connections_pacing = 0; 293 static uint32_t shadow_num_connections = 0; 294 295 static int tcp_pacing_limit = 10000; 296 SYSCTL_INT(_net_inet_tcp, OID_AUTO, pacing_limit, CTLFLAG_RW, 297 &tcp_pacing_limit, 1000, 298 "If the TCP stack does pacing, is there a limit (-1 = no, 0 = no pacing N = number of connections)"); 299 300 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, pacing_count, CTLFLAG_RD, 301 &shadow_num_connections, 0, "Number of TCP connections being paced"); 302 303 static int tcp_log_debug = 0; 304 SYSCTL_INT(_net_inet_tcp, OID_AUTO, log_debug, CTLFLAG_RW, 305 &tcp_log_debug, 0, "Log errors caused by incoming TCP segments"); 306 307 static int tcp_tcbhashsize; 308 SYSCTL_INT(_net_inet_tcp, OID_AUTO, tcbhashsize, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, 309 &tcp_tcbhashsize, 0, "Size of TCP control-block hashtable"); 310 311 static int do_tcpdrain = 1; 312 SYSCTL_INT(_net_inet_tcp, OID_AUTO, do_tcpdrain, CTLFLAG_RW, &do_tcpdrain, 0, 313 "Enable tcp_drain routine for extra help when low on mbufs"); 314 315 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, pcbcount, CTLFLAG_VNET | CTLFLAG_RD, 316 &VNET_NAME(tcbinfo.ipi_count), 0, "Number of active PCBs"); 317 318 VNET_DEFINE_STATIC(int, icmp_may_rst) = 1; 319 #define V_icmp_may_rst VNET(icmp_may_rst) 320 SYSCTL_INT(_net_inet_tcp, OID_AUTO, icmp_may_rst, CTLFLAG_VNET | CTLFLAG_RW, 321 &VNET_NAME(icmp_may_rst), 0, 322 "Certain ICMP unreachable messages may abort connections in SYN_SENT"); 323 324 VNET_DEFINE_STATIC(int, tcp_isn_reseed_interval) = 0; 325 #define V_tcp_isn_reseed_interval VNET(tcp_isn_reseed_interval) 326 SYSCTL_INT(_net_inet_tcp, OID_AUTO, isn_reseed_interval, CTLFLAG_VNET | CTLFLAG_RW, 327 &VNET_NAME(tcp_isn_reseed_interval), 0, 328 "Seconds between reseeding of ISN secret"); 329 330 static int tcp_soreceive_stream; 331 SYSCTL_INT(_net_inet_tcp, OID_AUTO, soreceive_stream, CTLFLAG_RDTUN, 332 &tcp_soreceive_stream, 0, "Using soreceive_stream for TCP sockets"); 333 334 VNET_DEFINE(uma_zone_t, sack_hole_zone); 335 #define V_sack_hole_zone VNET(sack_hole_zone) 336 VNET_DEFINE(uint32_t, tcp_map_entries_limit) = 0; /* unlimited */ 337 static int 338 sysctl_net_inet_tcp_map_limit_check(SYSCTL_HANDLER_ARGS) 339 { 340 int error; 341 uint32_t new; 342 343 new = V_tcp_map_entries_limit; 344 error = sysctl_handle_int(oidp, &new, 0, req); 345 if (error == 0 && req->newptr) { 346 /* only allow "0" and value > minimum */ 347 if (new > 0 && new < TCP_MIN_MAP_ENTRIES_LIMIT) 348 error = EINVAL; 349 else 350 V_tcp_map_entries_limit = new; 351 } 352 return (error); 353 } 354 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, map_limit, 355 CTLFLAG_VNET | CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 356 &VNET_NAME(tcp_map_entries_limit), 0, 357 &sysctl_net_inet_tcp_map_limit_check, "IU", 358 "Total sendmap entries limit"); 359 360 VNET_DEFINE(uint32_t, tcp_map_split_limit) = 0; /* unlimited */ 361 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, split_limit, CTLFLAG_VNET | CTLFLAG_RW, 362 &VNET_NAME(tcp_map_split_limit), 0, 363 "Total sendmap split entries limit"); 364 365 #ifdef TCP_HHOOK 366 VNET_DEFINE(struct hhook_head *, tcp_hhh[HHOOK_TCP_LAST+1]); 367 #endif 368 369 #define TS_OFFSET_SECRET_LENGTH SIPHASH_KEY_LENGTH 370 VNET_DEFINE_STATIC(u_char, ts_offset_secret[TS_OFFSET_SECRET_LENGTH]); 371 #define V_ts_offset_secret VNET(ts_offset_secret) 372 373 static int tcp_default_fb_init(struct tcpcb *tp); 374 static void tcp_default_fb_fini(struct tcpcb *tp, int tcb_is_purged); 375 static int tcp_default_handoff_ok(struct tcpcb *tp); 376 static struct inpcb *tcp_notify(struct inpcb *, int); 377 static struct inpcb *tcp_mtudisc_notify(struct inpcb *, int); 378 static void tcp_mtudisc(struct inpcb *, int); 379 static char * tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th, 380 void *ip4hdr, const void *ip6hdr); 381 382 static struct tcp_function_block tcp_def_funcblk = { 383 .tfb_tcp_block_name = "freebsd", 384 .tfb_tcp_output = tcp_output, 385 .tfb_tcp_do_segment = tcp_do_segment, 386 .tfb_tcp_ctloutput = tcp_default_ctloutput, 387 .tfb_tcp_handoff_ok = tcp_default_handoff_ok, 388 .tfb_tcp_fb_init = tcp_default_fb_init, 389 .tfb_tcp_fb_fini = tcp_default_fb_fini, 390 }; 391 392 static int tcp_fb_cnt = 0; 393 struct tcp_funchead t_functions; 394 static struct tcp_function_block *tcp_func_set_ptr = &tcp_def_funcblk; 395 396 void 397 tcp_record_dsack(struct tcpcb *tp, tcp_seq start, tcp_seq end, int tlp) 398 { 399 TCPSTAT_INC(tcps_dsack_count); 400 tp->t_dsack_pack++; 401 if (tlp == 0) { 402 if (SEQ_GT(end, start)) { 403 tp->t_dsack_bytes += (end - start); 404 TCPSTAT_ADD(tcps_dsack_bytes, (end - start)); 405 } else { 406 tp->t_dsack_tlp_bytes += (start - end); 407 TCPSTAT_ADD(tcps_dsack_bytes, (start - end)); 408 } 409 } else { 410 if (SEQ_GT(end, start)) { 411 tp->t_dsack_bytes += (end - start); 412 TCPSTAT_ADD(tcps_dsack_tlp_bytes, (end - start)); 413 } else { 414 tp->t_dsack_tlp_bytes += (start - end); 415 TCPSTAT_ADD(tcps_dsack_tlp_bytes, (start - end)); 416 } 417 } 418 } 419 420 static struct tcp_function_block * 421 find_tcp_functions_locked(struct tcp_function_set *fs) 422 { 423 struct tcp_function *f; 424 struct tcp_function_block *blk=NULL; 425 426 TAILQ_FOREACH(f, &t_functions, tf_next) { 427 if (strcmp(f->tf_name, fs->function_set_name) == 0) { 428 blk = f->tf_fb; 429 break; 430 } 431 } 432 return(blk); 433 } 434 435 static struct tcp_function_block * 436 find_tcp_fb_locked(struct tcp_function_block *blk, struct tcp_function **s) 437 { 438 struct tcp_function_block *rblk=NULL; 439 struct tcp_function *f; 440 441 TAILQ_FOREACH(f, &t_functions, tf_next) { 442 if (f->tf_fb == blk) { 443 rblk = blk; 444 if (s) { 445 *s = f; 446 } 447 break; 448 } 449 } 450 return (rblk); 451 } 452 453 struct tcp_function_block * 454 find_and_ref_tcp_functions(struct tcp_function_set *fs) 455 { 456 struct tcp_function_block *blk; 457 458 rw_rlock(&tcp_function_lock); 459 blk = find_tcp_functions_locked(fs); 460 if (blk) 461 refcount_acquire(&blk->tfb_refcnt); 462 rw_runlock(&tcp_function_lock); 463 return(blk); 464 } 465 466 struct tcp_function_block * 467 find_and_ref_tcp_fb(struct tcp_function_block *blk) 468 { 469 struct tcp_function_block *rblk; 470 471 rw_rlock(&tcp_function_lock); 472 rblk = find_tcp_fb_locked(blk, NULL); 473 if (rblk) 474 refcount_acquire(&rblk->tfb_refcnt); 475 rw_runlock(&tcp_function_lock); 476 return(rblk); 477 } 478 479 /* Find a matching alias for the given tcp_function_block. */ 480 int 481 find_tcp_function_alias(struct tcp_function_block *blk, 482 struct tcp_function_set *fs) 483 { 484 struct tcp_function *f; 485 int found; 486 487 found = 0; 488 rw_rlock(&tcp_function_lock); 489 TAILQ_FOREACH(f, &t_functions, tf_next) { 490 if ((f->tf_fb == blk) && 491 (strncmp(f->tf_name, blk->tfb_tcp_block_name, 492 TCP_FUNCTION_NAME_LEN_MAX) != 0)) { 493 /* Matching function block with different name. */ 494 strncpy(fs->function_set_name, f->tf_name, 495 TCP_FUNCTION_NAME_LEN_MAX); 496 found = 1; 497 break; 498 } 499 } 500 /* Null terminate the string appropriately. */ 501 if (found) { 502 fs->function_set_name[TCP_FUNCTION_NAME_LEN_MAX - 1] = '\0'; 503 } else { 504 fs->function_set_name[0] = '\0'; 505 } 506 rw_runlock(&tcp_function_lock); 507 return (found); 508 } 509 510 static struct tcp_function_block * 511 find_and_ref_tcp_default_fb(void) 512 { 513 struct tcp_function_block *rblk; 514 515 rw_rlock(&tcp_function_lock); 516 rblk = tcp_func_set_ptr; 517 refcount_acquire(&rblk->tfb_refcnt); 518 rw_runlock(&tcp_function_lock); 519 return (rblk); 520 } 521 522 void 523 tcp_switch_back_to_default(struct tcpcb *tp) 524 { 525 struct tcp_function_block *tfb; 526 527 KASSERT(tp->t_fb != &tcp_def_funcblk, 528 ("%s: called by the built-in default stack", __func__)); 529 530 /* 531 * Release the old stack. This function will either find a new one 532 * or panic. 533 */ 534 if (tp->t_fb->tfb_tcp_fb_fini != NULL) 535 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 0); 536 refcount_release(&tp->t_fb->tfb_refcnt); 537 538 /* 539 * Now, we'll find a new function block to use. 540 * Start by trying the current user-selected 541 * default, unless this stack is the user-selected 542 * default. 543 */ 544 tfb = find_and_ref_tcp_default_fb(); 545 if (tfb == tp->t_fb) { 546 refcount_release(&tfb->tfb_refcnt); 547 tfb = NULL; 548 } 549 /* Does the stack accept this connection? */ 550 if (tfb != NULL && tfb->tfb_tcp_handoff_ok != NULL && 551 (*tfb->tfb_tcp_handoff_ok)(tp)) { 552 refcount_release(&tfb->tfb_refcnt); 553 tfb = NULL; 554 } 555 /* Try to use that stack. */ 556 if (tfb != NULL) { 557 /* Initialize the new stack. If it succeeds, we are done. */ 558 tp->t_fb = tfb; 559 if (tp->t_fb->tfb_tcp_fb_init == NULL || 560 (*tp->t_fb->tfb_tcp_fb_init)(tp) == 0) 561 return; 562 563 /* 564 * Initialization failed. Release the reference count on 565 * the stack. 566 */ 567 refcount_release(&tfb->tfb_refcnt); 568 } 569 570 /* 571 * If that wasn't feasible, use the built-in default 572 * stack which is not allowed to reject anyone. 573 */ 574 tfb = find_and_ref_tcp_fb(&tcp_def_funcblk); 575 if (tfb == NULL) { 576 /* there always should be a default */ 577 panic("Can't refer to tcp_def_funcblk"); 578 } 579 if (tfb->tfb_tcp_handoff_ok != NULL) { 580 if ((*tfb->tfb_tcp_handoff_ok) (tp)) { 581 /* The default stack cannot say no */ 582 panic("Default stack rejects a new session?"); 583 } 584 } 585 tp->t_fb = tfb; 586 if (tp->t_fb->tfb_tcp_fb_init != NULL && 587 (*tp->t_fb->tfb_tcp_fb_init)(tp)) { 588 /* The default stack cannot fail */ 589 panic("Default stack initialization failed"); 590 } 591 } 592 593 static void 594 tcp_recv_udp_tunneled_packet(struct mbuf *m, int off, struct inpcb *inp, 595 const struct sockaddr *sa, void *ctx) 596 { 597 struct ip *iph; 598 #ifdef INET6 599 struct ip6_hdr *ip6; 600 #endif 601 struct udphdr *uh; 602 struct tcphdr *th; 603 int thlen; 604 uint16_t port; 605 606 TCPSTAT_INC(tcps_tunneled_pkts); 607 if ((m->m_flags & M_PKTHDR) == 0) { 608 /* Can't handle one that is not a pkt hdr */ 609 TCPSTAT_INC(tcps_tunneled_errs); 610 goto out; 611 } 612 thlen = sizeof(struct tcphdr); 613 if (m->m_len < off + sizeof(struct udphdr) + thlen && 614 (m = m_pullup(m, off + sizeof(struct udphdr) + thlen)) == NULL) { 615 TCPSTAT_INC(tcps_tunneled_errs); 616 goto out; 617 } 618 iph = mtod(m, struct ip *); 619 uh = (struct udphdr *)((caddr_t)iph + off); 620 th = (struct tcphdr *)(uh + 1); 621 thlen = th->th_off << 2; 622 if (m->m_len < off + sizeof(struct udphdr) + thlen) { 623 m = m_pullup(m, off + sizeof(struct udphdr) + thlen); 624 if (m == NULL) { 625 TCPSTAT_INC(tcps_tunneled_errs); 626 goto out; 627 } else { 628 iph = mtod(m, struct ip *); 629 uh = (struct udphdr *)((caddr_t)iph + off); 630 th = (struct tcphdr *)(uh + 1); 631 } 632 } 633 m->m_pkthdr.tcp_tun_port = port = uh->uh_sport; 634 bcopy(th, uh, m->m_len - off); 635 m->m_len -= sizeof(struct udphdr); 636 m->m_pkthdr.len -= sizeof(struct udphdr); 637 /* 638 * We use the same algorithm for 639 * both UDP and TCP for c-sum. So 640 * the code in tcp_input will skip 641 * the checksum. So we do nothing 642 * with the flag (m->m_pkthdr.csum_flags). 643 */ 644 switch (iph->ip_v) { 645 #ifdef INET 646 case IPVERSION: 647 iph->ip_len = htons(ntohs(iph->ip_len) - sizeof(struct udphdr)); 648 tcp_input_with_port(&m, &off, IPPROTO_TCP, port); 649 break; 650 #endif 651 #ifdef INET6 652 case IPV6_VERSION >> 4: 653 ip6 = mtod(m, struct ip6_hdr *); 654 ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - sizeof(struct udphdr)); 655 tcp6_input_with_port(&m, &off, IPPROTO_TCP, port); 656 break; 657 #endif 658 default: 659 goto out; 660 break; 661 } 662 return; 663 out: 664 m_freem(m); 665 } 666 667 static int 668 sysctl_net_inet_default_tcp_functions(SYSCTL_HANDLER_ARGS) 669 { 670 int error=ENOENT; 671 struct tcp_function_set fs; 672 struct tcp_function_block *blk; 673 674 memset(&fs, 0, sizeof(fs)); 675 rw_rlock(&tcp_function_lock); 676 blk = find_tcp_fb_locked(tcp_func_set_ptr, NULL); 677 if (blk) { 678 /* Found him */ 679 strcpy(fs.function_set_name, blk->tfb_tcp_block_name); 680 fs.pcbcnt = blk->tfb_refcnt; 681 } 682 rw_runlock(&tcp_function_lock); 683 error = sysctl_handle_string(oidp, fs.function_set_name, 684 sizeof(fs.function_set_name), req); 685 686 /* Check for error or no change */ 687 if (error != 0 || req->newptr == NULL) 688 return(error); 689 690 rw_wlock(&tcp_function_lock); 691 blk = find_tcp_functions_locked(&fs); 692 if ((blk == NULL) || 693 (blk->tfb_flags & TCP_FUNC_BEING_REMOVED)) { 694 error = ENOENT; 695 goto done; 696 } 697 tcp_func_set_ptr = blk; 698 done: 699 rw_wunlock(&tcp_function_lock); 700 return (error); 701 } 702 703 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, functions_default, 704 CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 705 NULL, 0, sysctl_net_inet_default_tcp_functions, "A", 706 "Set/get the default TCP functions"); 707 708 static int 709 sysctl_net_inet_list_available(SYSCTL_HANDLER_ARGS) 710 { 711 int error, cnt, linesz; 712 struct tcp_function *f; 713 char *buffer, *cp; 714 size_t bufsz, outsz; 715 bool alias; 716 717 cnt = 0; 718 rw_rlock(&tcp_function_lock); 719 TAILQ_FOREACH(f, &t_functions, tf_next) { 720 cnt++; 721 } 722 rw_runlock(&tcp_function_lock); 723 724 bufsz = (cnt+2) * ((TCP_FUNCTION_NAME_LEN_MAX * 2) + 13) + 1; 725 buffer = malloc(bufsz, M_TEMP, M_WAITOK); 726 727 error = 0; 728 cp = buffer; 729 730 linesz = snprintf(cp, bufsz, "\n%-32s%c %-32s %s\n", "Stack", 'D', 731 "Alias", "PCB count"); 732 cp += linesz; 733 bufsz -= linesz; 734 outsz = linesz; 735 736 rw_rlock(&tcp_function_lock); 737 TAILQ_FOREACH(f, &t_functions, tf_next) { 738 alias = (f->tf_name != f->tf_fb->tfb_tcp_block_name); 739 linesz = snprintf(cp, bufsz, "%-32s%c %-32s %u\n", 740 f->tf_fb->tfb_tcp_block_name, 741 (f->tf_fb == tcp_func_set_ptr) ? '*' : ' ', 742 alias ? f->tf_name : "-", 743 f->tf_fb->tfb_refcnt); 744 if (linesz >= bufsz) { 745 error = EOVERFLOW; 746 break; 747 } 748 cp += linesz; 749 bufsz -= linesz; 750 outsz += linesz; 751 } 752 rw_runlock(&tcp_function_lock); 753 if (error == 0) 754 error = sysctl_handle_string(oidp, buffer, outsz + 1, req); 755 free(buffer, M_TEMP); 756 return (error); 757 } 758 759 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, functions_available, 760 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT, 761 NULL, 0, sysctl_net_inet_list_available, "A", 762 "list available TCP Function sets"); 763 764 VNET_DEFINE(int, tcp_udp_tunneling_port) = TCP_TUNNELING_PORT_DEFAULT; 765 766 #ifdef INET 767 VNET_DEFINE(struct socket *, udp4_tun_socket) = NULL; 768 #define V_udp4_tun_socket VNET(udp4_tun_socket) 769 #endif 770 #ifdef INET6 771 VNET_DEFINE(struct socket *, udp6_tun_socket) = NULL; 772 #define V_udp6_tun_socket VNET(udp6_tun_socket) 773 #endif 774 775 static void 776 tcp_over_udp_stop(void) 777 { 778 /* 779 * This function assumes sysctl caller holds inp_rinfo_lock() 780 * for writing! 781 */ 782 #ifdef INET 783 if (V_udp4_tun_socket != NULL) { 784 soclose(V_udp4_tun_socket); 785 V_udp4_tun_socket = NULL; 786 } 787 #endif 788 #ifdef INET6 789 if (V_udp6_tun_socket != NULL) { 790 soclose(V_udp6_tun_socket); 791 V_udp6_tun_socket = NULL; 792 } 793 #endif 794 } 795 796 static int 797 tcp_over_udp_start(void) 798 { 799 uint16_t port; 800 int ret; 801 #ifdef INET 802 struct sockaddr_in sin; 803 #endif 804 #ifdef INET6 805 struct sockaddr_in6 sin6; 806 #endif 807 /* 808 * This function assumes sysctl caller holds inp_info_rlock() 809 * for writing! 810 */ 811 port = V_tcp_udp_tunneling_port; 812 if (ntohs(port) == 0) { 813 /* Must have a port set */ 814 return (EINVAL); 815 } 816 #ifdef INET 817 if (V_udp4_tun_socket != NULL) { 818 /* Already running -- must stop first */ 819 return (EALREADY); 820 } 821 #endif 822 #ifdef INET6 823 if (V_udp6_tun_socket != NULL) { 824 /* Already running -- must stop first */ 825 return (EALREADY); 826 } 827 #endif 828 #ifdef INET 829 if ((ret = socreate(PF_INET, &V_udp4_tun_socket, 830 SOCK_DGRAM, IPPROTO_UDP, 831 curthread->td_ucred, curthread))) { 832 tcp_over_udp_stop(); 833 return (ret); 834 } 835 /* Call the special UDP hook. */ 836 if ((ret = udp_set_kernel_tunneling(V_udp4_tun_socket, 837 tcp_recv_udp_tunneled_packet, 838 tcp_ctlinput_viaudp, 839 NULL))) { 840 tcp_over_udp_stop(); 841 return (ret); 842 } 843 /* Ok, we have a socket, bind it to the port. */ 844 memset(&sin, 0, sizeof(struct sockaddr_in)); 845 sin.sin_len = sizeof(struct sockaddr_in); 846 sin.sin_family = AF_INET; 847 sin.sin_port = htons(port); 848 if ((ret = sobind(V_udp4_tun_socket, 849 (struct sockaddr *)&sin, curthread))) { 850 tcp_over_udp_stop(); 851 return (ret); 852 } 853 #endif 854 #ifdef INET6 855 if ((ret = socreate(PF_INET6, &V_udp6_tun_socket, 856 SOCK_DGRAM, IPPROTO_UDP, 857 curthread->td_ucred, curthread))) { 858 tcp_over_udp_stop(); 859 return (ret); 860 } 861 /* Call the special UDP hook. */ 862 if ((ret = udp_set_kernel_tunneling(V_udp6_tun_socket, 863 tcp_recv_udp_tunneled_packet, 864 tcp6_ctlinput_viaudp, 865 NULL))) { 866 tcp_over_udp_stop(); 867 return (ret); 868 } 869 /* Ok, we have a socket, bind it to the port. */ 870 memset(&sin6, 0, sizeof(struct sockaddr_in6)); 871 sin6.sin6_len = sizeof(struct sockaddr_in6); 872 sin6.sin6_family = AF_INET6; 873 sin6.sin6_port = htons(port); 874 if ((ret = sobind(V_udp6_tun_socket, 875 (struct sockaddr *)&sin6, curthread))) { 876 tcp_over_udp_stop(); 877 return (ret); 878 } 879 #endif 880 return (0); 881 } 882 883 static int 884 sysctl_net_inet_tcp_udp_tunneling_port_check(SYSCTL_HANDLER_ARGS) 885 { 886 int error; 887 uint32_t old, new; 888 889 old = V_tcp_udp_tunneling_port; 890 new = old; 891 error = sysctl_handle_int(oidp, &new, 0, req); 892 if ((error == 0) && 893 (req->newptr != NULL)) { 894 if ((new < TCP_TUNNELING_PORT_MIN) || 895 (new > TCP_TUNNELING_PORT_MAX)) { 896 error = EINVAL; 897 } else { 898 V_tcp_udp_tunneling_port = new; 899 if (old != 0) { 900 tcp_over_udp_stop(); 901 } 902 if (new != 0) { 903 error = tcp_over_udp_start(); 904 } 905 } 906 } 907 return (error); 908 } 909 910 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, udp_tunneling_port, 911 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 912 &VNET_NAME(tcp_udp_tunneling_port), 913 0, &sysctl_net_inet_tcp_udp_tunneling_port_check, "IU", 914 "Tunneling port for tcp over udp"); 915 916 VNET_DEFINE(int, tcp_udp_tunneling_overhead) = TCP_TUNNELING_OVERHEAD_DEFAULT; 917 918 static int 919 sysctl_net_inet_tcp_udp_tunneling_overhead_check(SYSCTL_HANDLER_ARGS) 920 { 921 int error, new; 922 923 new = V_tcp_udp_tunneling_overhead; 924 error = sysctl_handle_int(oidp, &new, 0, req); 925 if (error == 0 && req->newptr) { 926 if ((new < TCP_TUNNELING_OVERHEAD_MIN) || 927 (new > TCP_TUNNELING_OVERHEAD_MAX)) 928 error = EINVAL; 929 else 930 V_tcp_udp_tunneling_overhead = new; 931 } 932 return (error); 933 } 934 935 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, udp_tunneling_overhead, 936 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 937 &VNET_NAME(tcp_udp_tunneling_overhead), 938 0, &sysctl_net_inet_tcp_udp_tunneling_overhead_check, "IU", 939 "MSS reduction when using tcp over udp"); 940 941 /* 942 * Exports one (struct tcp_function_info) for each alias/name. 943 */ 944 static int 945 sysctl_net_inet_list_func_info(SYSCTL_HANDLER_ARGS) 946 { 947 int cnt, error; 948 struct tcp_function *f; 949 struct tcp_function_info tfi; 950 951 /* 952 * We don't allow writes. 953 */ 954 if (req->newptr != NULL) 955 return (EINVAL); 956 957 /* 958 * Wire the old buffer so we can directly copy the functions to 959 * user space without dropping the lock. 960 */ 961 if (req->oldptr != NULL) { 962 error = sysctl_wire_old_buffer(req, 0); 963 if (error) 964 return (error); 965 } 966 967 /* 968 * Walk the list and copy out matching entries. If INVARIANTS 969 * is compiled in, also walk the list to verify the length of 970 * the list matches what we have recorded. 971 */ 972 rw_rlock(&tcp_function_lock); 973 974 cnt = 0; 975 #ifndef INVARIANTS 976 if (req->oldptr == NULL) { 977 cnt = tcp_fb_cnt; 978 goto skip_loop; 979 } 980 #endif 981 TAILQ_FOREACH(f, &t_functions, tf_next) { 982 #ifdef INVARIANTS 983 cnt++; 984 #endif 985 if (req->oldptr != NULL) { 986 bzero(&tfi, sizeof(tfi)); 987 tfi.tfi_refcnt = f->tf_fb->tfb_refcnt; 988 tfi.tfi_id = f->tf_fb->tfb_id; 989 (void)strlcpy(tfi.tfi_alias, f->tf_name, 990 sizeof(tfi.tfi_alias)); 991 (void)strlcpy(tfi.tfi_name, 992 f->tf_fb->tfb_tcp_block_name, sizeof(tfi.tfi_name)); 993 error = SYSCTL_OUT(req, &tfi, sizeof(tfi)); 994 /* 995 * Don't stop on error, as that is the 996 * mechanism we use to accumulate length 997 * information if the buffer was too short. 998 */ 999 } 1000 } 1001 KASSERT(cnt == tcp_fb_cnt, 1002 ("%s: cnt (%d) != tcp_fb_cnt (%d)", __func__, cnt, tcp_fb_cnt)); 1003 #ifndef INVARIANTS 1004 skip_loop: 1005 #endif 1006 rw_runlock(&tcp_function_lock); 1007 if (req->oldptr == NULL) 1008 error = SYSCTL_OUT(req, NULL, 1009 (cnt + 1) * sizeof(struct tcp_function_info)); 1010 1011 return (error); 1012 } 1013 1014 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, function_info, 1015 CTLTYPE_OPAQUE | CTLFLAG_SKIP | CTLFLAG_RD | CTLFLAG_MPSAFE, 1016 NULL, 0, sysctl_net_inet_list_func_info, "S,tcp_function_info", 1017 "List TCP function block name-to-ID mappings"); 1018 1019 /* 1020 * tfb_tcp_handoff_ok() function for the default stack. 1021 * Note that we'll basically try to take all comers. 1022 */ 1023 static int 1024 tcp_default_handoff_ok(struct tcpcb *tp) 1025 { 1026 1027 return (0); 1028 } 1029 1030 /* 1031 * tfb_tcp_fb_init() function for the default stack. 1032 * 1033 * This handles making sure we have appropriate timers set if you are 1034 * transitioning a socket that has some amount of setup done. 1035 * 1036 * The init() fuction from the default can *never* return non-zero i.e. 1037 * it is required to always succeed since it is the stack of last resort! 1038 */ 1039 static int 1040 tcp_default_fb_init(struct tcpcb *tp) 1041 { 1042 1043 struct socket *so; 1044 1045 INP_WLOCK_ASSERT(tp->t_inpcb); 1046 1047 KASSERT(tp->t_state >= 0 && tp->t_state < TCPS_TIME_WAIT, 1048 ("%s: connection %p in unexpected state %d", __func__, tp, 1049 tp->t_state)); 1050 1051 /* 1052 * Nothing to do for ESTABLISHED or LISTEN states. And, we don't 1053 * know what to do for unexpected states (which includes TIME_WAIT). 1054 */ 1055 if (tp->t_state <= TCPS_LISTEN || tp->t_state >= TCPS_TIME_WAIT) 1056 return (0); 1057 1058 /* 1059 * Make sure some kind of transmission timer is set if there is 1060 * outstanding data. 1061 */ 1062 so = tp->t_inpcb->inp_socket; 1063 if ((!TCPS_HAVEESTABLISHED(tp->t_state) || sbavail(&so->so_snd) || 1064 tp->snd_una != tp->snd_max) && !(tcp_timer_active(tp, TT_REXMT) || 1065 tcp_timer_active(tp, TT_PERSIST))) { 1066 /* 1067 * If the session has established and it looks like it should 1068 * be in the persist state, set the persist timer. Otherwise, 1069 * set the retransmit timer. 1070 */ 1071 if (TCPS_HAVEESTABLISHED(tp->t_state) && tp->snd_wnd == 0 && 1072 (int32_t)(tp->snd_nxt - tp->snd_una) < 1073 (int32_t)sbavail(&so->so_snd)) 1074 tcp_setpersist(tp); 1075 else 1076 tcp_timer_activate(tp, TT_REXMT, tp->t_rxtcur); 1077 } 1078 1079 /* All non-embryonic sessions get a keepalive timer. */ 1080 if (!tcp_timer_active(tp, TT_KEEP)) 1081 tcp_timer_activate(tp, TT_KEEP, 1082 TCPS_HAVEESTABLISHED(tp->t_state) ? TP_KEEPIDLE(tp) : 1083 TP_KEEPINIT(tp)); 1084 1085 /* 1086 * Make sure critical variables are initialized 1087 * if transitioning while in Recovery. 1088 */ 1089 if IN_FASTRECOVERY(tp->t_flags) { 1090 if (tp->sackhint.recover_fs == 0) 1091 tp->sackhint.recover_fs = max(1, 1092 tp->snd_nxt - tp->snd_una); 1093 } 1094 1095 return (0); 1096 } 1097 1098 /* 1099 * tfb_tcp_fb_fini() function for the default stack. 1100 * 1101 * This changes state as necessary (or prudent) to prepare for another stack 1102 * to assume responsibility for the connection. 1103 */ 1104 static void 1105 tcp_default_fb_fini(struct tcpcb *tp, int tcb_is_purged) 1106 { 1107 1108 INP_WLOCK_ASSERT(tp->t_inpcb); 1109 return; 1110 } 1111 1112 /* 1113 * Target size of TCP PCB hash tables. Must be a power of two. 1114 * 1115 * Note that this can be overridden by the kernel environment 1116 * variable net.inet.tcp.tcbhashsize 1117 */ 1118 #ifndef TCBHASHSIZE 1119 #define TCBHASHSIZE 0 1120 #endif 1121 1122 /* 1123 * XXX 1124 * Callouts should be moved into struct tcp directly. They are currently 1125 * separate because the tcpcb structure is exported to userland for sysctl 1126 * parsing purposes, which do not know about callouts. 1127 */ 1128 struct tcpcb_mem { 1129 struct tcpcb tcb; 1130 struct tcp_timer tt; 1131 struct cc_var ccv; 1132 #ifdef TCP_HHOOK 1133 struct osd osd; 1134 #endif 1135 }; 1136 1137 VNET_DEFINE_STATIC(uma_zone_t, tcpcb_zone); 1138 #define V_tcpcb_zone VNET(tcpcb_zone) 1139 1140 MALLOC_DEFINE(M_TCPLOG, "tcplog", "TCP address and flags print buffers"); 1141 MALLOC_DEFINE(M_TCPFUNCTIONS, "tcpfunc", "TCP function set memory"); 1142 1143 static struct mtx isn_mtx; 1144 1145 #define ISN_LOCK_INIT() mtx_init(&isn_mtx, "isn_mtx", NULL, MTX_DEF) 1146 #define ISN_LOCK() mtx_lock(&isn_mtx) 1147 #define ISN_UNLOCK() mtx_unlock(&isn_mtx) 1148 1149 /* 1150 * TCP initialization. 1151 */ 1152 static void 1153 tcp_zone_change(void *tag) 1154 { 1155 1156 uma_zone_set_max(V_tcbinfo.ipi_zone, maxsockets); 1157 uma_zone_set_max(V_tcpcb_zone, maxsockets); 1158 tcp_tw_zone_change(); 1159 } 1160 1161 static int 1162 tcp_inpcb_init(void *mem, int size, int flags) 1163 { 1164 struct inpcb *inp = mem; 1165 1166 INP_LOCK_INIT(inp, "inp", "tcpinp"); 1167 return (0); 1168 } 1169 1170 /* 1171 * Take a value and get the next power of 2 that doesn't overflow. 1172 * Used to size the tcp_inpcb hash buckets. 1173 */ 1174 static int 1175 maketcp_hashsize(int size) 1176 { 1177 int hashsize; 1178 1179 /* 1180 * auto tune. 1181 * get the next power of 2 higher than maxsockets. 1182 */ 1183 hashsize = 1 << fls(size); 1184 /* catch overflow, and just go one power of 2 smaller */ 1185 if (hashsize < size) { 1186 hashsize = 1 << (fls(size) - 1); 1187 } 1188 return (hashsize); 1189 } 1190 1191 static volatile int next_tcp_stack_id = 1; 1192 1193 /* 1194 * Register a TCP function block with the name provided in the names 1195 * array. (Note that this function does NOT automatically register 1196 * blk->tfb_tcp_block_name as a stack name. Therefore, you should 1197 * explicitly include blk->tfb_tcp_block_name in the list of names if 1198 * you wish to register the stack with that name.) 1199 * 1200 * Either all name registrations will succeed or all will fail. If 1201 * a name registration fails, the function will update the num_names 1202 * argument to point to the array index of the name that encountered 1203 * the failure. 1204 * 1205 * Returns 0 on success, or an error code on failure. 1206 */ 1207 int 1208 register_tcp_functions_as_names(struct tcp_function_block *blk, int wait, 1209 const char *names[], int *num_names) 1210 { 1211 struct tcp_function *n; 1212 struct tcp_function_set fs; 1213 int error, i; 1214 1215 KASSERT(names != NULL && *num_names > 0, 1216 ("%s: Called with 0-length name list", __func__)); 1217 KASSERT(names != NULL, ("%s: Called with NULL name list", __func__)); 1218 KASSERT(rw_initialized(&tcp_function_lock), 1219 ("%s: called too early", __func__)); 1220 1221 if ((blk->tfb_tcp_output == NULL) || 1222 (blk->tfb_tcp_do_segment == NULL) || 1223 (blk->tfb_tcp_ctloutput == NULL) || 1224 (strlen(blk->tfb_tcp_block_name) == 0)) { 1225 /* 1226 * These functions are required and you 1227 * need a name. 1228 */ 1229 *num_names = 0; 1230 return (EINVAL); 1231 } 1232 if (blk->tfb_tcp_timer_stop_all || 1233 blk->tfb_tcp_timer_activate || 1234 blk->tfb_tcp_timer_active || 1235 blk->tfb_tcp_timer_stop) { 1236 /* 1237 * If you define one timer function you 1238 * must have them all. 1239 */ 1240 if ((blk->tfb_tcp_timer_stop_all == NULL) || 1241 (blk->tfb_tcp_timer_activate == NULL) || 1242 (blk->tfb_tcp_timer_active == NULL) || 1243 (blk->tfb_tcp_timer_stop == NULL)) { 1244 *num_names = 0; 1245 return (EINVAL); 1246 } 1247 } 1248 1249 if (blk->tfb_flags & TCP_FUNC_BEING_REMOVED) { 1250 *num_names = 0; 1251 return (EINVAL); 1252 } 1253 1254 refcount_init(&blk->tfb_refcnt, 0); 1255 blk->tfb_id = atomic_fetchadd_int(&next_tcp_stack_id, 1); 1256 for (i = 0; i < *num_names; i++) { 1257 n = malloc(sizeof(struct tcp_function), M_TCPFUNCTIONS, wait); 1258 if (n == NULL) { 1259 error = ENOMEM; 1260 goto cleanup; 1261 } 1262 n->tf_fb = blk; 1263 1264 (void)strlcpy(fs.function_set_name, names[i], 1265 sizeof(fs.function_set_name)); 1266 rw_wlock(&tcp_function_lock); 1267 if (find_tcp_functions_locked(&fs) != NULL) { 1268 /* Duplicate name space not allowed */ 1269 rw_wunlock(&tcp_function_lock); 1270 free(n, M_TCPFUNCTIONS); 1271 error = EALREADY; 1272 goto cleanup; 1273 } 1274 (void)strlcpy(n->tf_name, names[i], sizeof(n->tf_name)); 1275 TAILQ_INSERT_TAIL(&t_functions, n, tf_next); 1276 tcp_fb_cnt++; 1277 rw_wunlock(&tcp_function_lock); 1278 } 1279 return(0); 1280 1281 cleanup: 1282 /* 1283 * Deregister the names we just added. Because registration failed 1284 * for names[i], we don't need to deregister that name. 1285 */ 1286 *num_names = i; 1287 rw_wlock(&tcp_function_lock); 1288 while (--i >= 0) { 1289 TAILQ_FOREACH(n, &t_functions, tf_next) { 1290 if (!strncmp(n->tf_name, names[i], 1291 TCP_FUNCTION_NAME_LEN_MAX)) { 1292 TAILQ_REMOVE(&t_functions, n, tf_next); 1293 tcp_fb_cnt--; 1294 n->tf_fb = NULL; 1295 free(n, M_TCPFUNCTIONS); 1296 break; 1297 } 1298 } 1299 } 1300 rw_wunlock(&tcp_function_lock); 1301 return (error); 1302 } 1303 1304 /* 1305 * Register a TCP function block using the name provided in the name 1306 * argument. 1307 * 1308 * Returns 0 on success, or an error code on failure. 1309 */ 1310 int 1311 register_tcp_functions_as_name(struct tcp_function_block *blk, const char *name, 1312 int wait) 1313 { 1314 const char *name_list[1]; 1315 int num_names, rv; 1316 1317 num_names = 1; 1318 if (name != NULL) 1319 name_list[0] = name; 1320 else 1321 name_list[0] = blk->tfb_tcp_block_name; 1322 rv = register_tcp_functions_as_names(blk, wait, name_list, &num_names); 1323 return (rv); 1324 } 1325 1326 /* 1327 * Register a TCP function block using the name defined in 1328 * blk->tfb_tcp_block_name. 1329 * 1330 * Returns 0 on success, or an error code on failure. 1331 */ 1332 int 1333 register_tcp_functions(struct tcp_function_block *blk, int wait) 1334 { 1335 1336 return (register_tcp_functions_as_name(blk, NULL, wait)); 1337 } 1338 1339 /* 1340 * Deregister all names associated with a function block. This 1341 * functionally removes the function block from use within the system. 1342 * 1343 * When called with a true quiesce argument, mark the function block 1344 * as being removed so no more stacks will use it and determine 1345 * whether the removal would succeed. 1346 * 1347 * When called with a false quiesce argument, actually attempt the 1348 * removal. 1349 * 1350 * When called with a force argument, attempt to switch all TCBs to 1351 * use the default stack instead of returning EBUSY. 1352 * 1353 * Returns 0 on success (or if the removal would succeed, or an error 1354 * code on failure. 1355 */ 1356 int 1357 deregister_tcp_functions(struct tcp_function_block *blk, bool quiesce, 1358 bool force) 1359 { 1360 struct tcp_function *f; 1361 1362 if (blk == &tcp_def_funcblk) { 1363 /* You can't un-register the default */ 1364 return (EPERM); 1365 } 1366 rw_wlock(&tcp_function_lock); 1367 if (blk == tcp_func_set_ptr) { 1368 /* You can't free the current default */ 1369 rw_wunlock(&tcp_function_lock); 1370 return (EBUSY); 1371 } 1372 /* Mark the block so no more stacks can use it. */ 1373 blk->tfb_flags |= TCP_FUNC_BEING_REMOVED; 1374 /* 1375 * If TCBs are still attached to the stack, attempt to switch them 1376 * to the default stack. 1377 */ 1378 if (force && blk->tfb_refcnt) { 1379 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, 1380 INPLOOKUP_WLOCKPCB); 1381 struct inpcb *inp; 1382 struct tcpcb *tp; 1383 VNET_ITERATOR_DECL(vnet_iter); 1384 1385 rw_wunlock(&tcp_function_lock); 1386 1387 VNET_LIST_RLOCK(); 1388 VNET_FOREACH(vnet_iter) { 1389 CURVNET_SET(vnet_iter); 1390 while ((inp = inp_next(&inpi)) != NULL) { 1391 if (inp->inp_flags & INP_TIMEWAIT) 1392 continue; 1393 tp = intotcpcb(inp); 1394 if (tp == NULL || tp->t_fb != blk) 1395 continue; 1396 tcp_switch_back_to_default(tp); 1397 } 1398 CURVNET_RESTORE(); 1399 } 1400 VNET_LIST_RUNLOCK(); 1401 1402 rw_wlock(&tcp_function_lock); 1403 } 1404 if (blk->tfb_refcnt) { 1405 /* TCBs still attached. */ 1406 rw_wunlock(&tcp_function_lock); 1407 return (EBUSY); 1408 } 1409 if (quiesce) { 1410 /* Skip removal. */ 1411 rw_wunlock(&tcp_function_lock); 1412 return (0); 1413 } 1414 /* Remove any function names that map to this function block. */ 1415 while (find_tcp_fb_locked(blk, &f) != NULL) { 1416 TAILQ_REMOVE(&t_functions, f, tf_next); 1417 tcp_fb_cnt--; 1418 f->tf_fb = NULL; 1419 free(f, M_TCPFUNCTIONS); 1420 } 1421 rw_wunlock(&tcp_function_lock); 1422 return (0); 1423 } 1424 1425 void 1426 tcp_init(void) 1427 { 1428 const char *tcbhash_tuneable; 1429 int hashsize; 1430 1431 tcbhash_tuneable = "net.inet.tcp.tcbhashsize"; 1432 1433 #ifdef TCP_HHOOK 1434 if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN, 1435 &V_tcp_hhh[HHOOK_TCP_EST_IN], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0) 1436 printf("%s: WARNING: unable to register helper hook\n", __func__); 1437 if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT, 1438 &V_tcp_hhh[HHOOK_TCP_EST_OUT], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0) 1439 printf("%s: WARNING: unable to register helper hook\n", __func__); 1440 #endif 1441 #ifdef STATS 1442 if (tcp_stats_init()) 1443 printf("%s: WARNING: unable to initialise TCP stats\n", 1444 __func__); 1445 #endif 1446 hashsize = TCBHASHSIZE; 1447 TUNABLE_INT_FETCH(tcbhash_tuneable, &hashsize); 1448 if (hashsize == 0) { 1449 /* 1450 * Auto tune the hash size based on maxsockets. 1451 * A perfect hash would have a 1:1 mapping 1452 * (hashsize = maxsockets) however it's been 1453 * suggested that O(2) average is better. 1454 */ 1455 hashsize = maketcp_hashsize(maxsockets / 4); 1456 /* 1457 * Our historical default is 512, 1458 * do not autotune lower than this. 1459 */ 1460 if (hashsize < 512) 1461 hashsize = 512; 1462 if (bootverbose && IS_DEFAULT_VNET(curvnet)) 1463 printf("%s: %s auto tuned to %d\n", __func__, 1464 tcbhash_tuneable, hashsize); 1465 } 1466 /* 1467 * We require a hashsize to be a power of two. 1468 * Previously if it was not a power of two we would just reset it 1469 * back to 512, which could be a nasty surprise if you did not notice 1470 * the error message. 1471 * Instead what we do is clip it to the closest power of two lower 1472 * than the specified hash value. 1473 */ 1474 if (!powerof2(hashsize)) { 1475 int oldhashsize = hashsize; 1476 1477 hashsize = maketcp_hashsize(hashsize); 1478 /* prevent absurdly low value */ 1479 if (hashsize < 16) 1480 hashsize = 16; 1481 printf("%s: WARNING: TCB hash size not a power of 2, " 1482 "clipped from %d to %d.\n", __func__, oldhashsize, 1483 hashsize); 1484 } 1485 in_pcbinfo_init(&V_tcbinfo, "tcp", hashsize, hashsize, 1486 "tcp_inpcb", tcp_inpcb_init); 1487 1488 /* 1489 * These have to be type stable for the benefit of the timers. 1490 */ 1491 V_tcpcb_zone = uma_zcreate("tcpcb", sizeof(struct tcpcb_mem), 1492 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 1493 uma_zone_set_max(V_tcpcb_zone, maxsockets); 1494 uma_zone_set_warning(V_tcpcb_zone, "kern.ipc.maxsockets limit reached"); 1495 1496 tcp_tw_init(); 1497 syncache_init(); 1498 tcp_hc_init(); 1499 1500 TUNABLE_INT_FETCH("net.inet.tcp.sack.enable", &V_tcp_do_sack); 1501 V_sack_hole_zone = uma_zcreate("sackhole", sizeof(struct sackhole), 1502 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 1503 1504 tcp_fastopen_init(); 1505 1506 COUNTER_ARRAY_ALLOC(V_tcps_states, TCP_NSTATES, M_WAITOK); 1507 VNET_PCPUSTAT_ALLOC(tcpstat, M_WAITOK); 1508 1509 V_tcp_msl = TCPTV_MSL; 1510 1511 /* Skip initialization of globals for non-default instances. */ 1512 if (!IS_DEFAULT_VNET(curvnet)) 1513 return; 1514 1515 tcp_reass_global_init(); 1516 1517 /* XXX virtualize those below? */ 1518 tcp_delacktime = TCPTV_DELACK; 1519 tcp_keepinit = TCPTV_KEEP_INIT; 1520 tcp_keepidle = TCPTV_KEEP_IDLE; 1521 tcp_keepintvl = TCPTV_KEEPINTVL; 1522 tcp_maxpersistidle = TCPTV_KEEP_IDLE; 1523 tcp_rexmit_initial = TCPTV_RTOBASE; 1524 if (tcp_rexmit_initial < 1) 1525 tcp_rexmit_initial = 1; 1526 tcp_rexmit_min = TCPTV_MIN; 1527 if (tcp_rexmit_min < 1) 1528 tcp_rexmit_min = 1; 1529 tcp_persmin = TCPTV_PERSMIN; 1530 tcp_persmax = TCPTV_PERSMAX; 1531 tcp_rexmit_slop = TCPTV_CPU_VAR; 1532 tcp_finwait2_timeout = TCPTV_FINWAIT2_TIMEOUT; 1533 tcp_tcbhashsize = hashsize; 1534 1535 /* Setup the tcp function block list */ 1536 TAILQ_INIT(&t_functions); 1537 rw_init(&tcp_function_lock, "tcp_func_lock"); 1538 register_tcp_functions(&tcp_def_funcblk, M_WAITOK); 1539 #ifdef TCP_BLACKBOX 1540 /* Initialize the TCP logging data. */ 1541 tcp_log_init(); 1542 #endif 1543 arc4rand(&V_ts_offset_secret, sizeof(V_ts_offset_secret), 0); 1544 1545 if (tcp_soreceive_stream) { 1546 #ifdef INET 1547 tcp_usrreqs.pru_soreceive = soreceive_stream; 1548 #endif 1549 #ifdef INET6 1550 tcp6_usrreqs.pru_soreceive = soreceive_stream; 1551 #endif /* INET6 */ 1552 } 1553 1554 #ifdef INET6 1555 #define TCP_MINPROTOHDR (sizeof(struct ip6_hdr) + sizeof(struct tcphdr)) 1556 #else /* INET6 */ 1557 #define TCP_MINPROTOHDR (sizeof(struct tcpiphdr)) 1558 #endif /* INET6 */ 1559 if (max_protohdr < TCP_MINPROTOHDR) 1560 max_protohdr = TCP_MINPROTOHDR; 1561 if (max_linkhdr + TCP_MINPROTOHDR > MHLEN) 1562 panic("tcp_init"); 1563 #undef TCP_MINPROTOHDR 1564 1565 ISN_LOCK_INIT(); 1566 EVENTHANDLER_REGISTER(shutdown_pre_sync, tcp_fini, NULL, 1567 SHUTDOWN_PRI_DEFAULT); 1568 EVENTHANDLER_REGISTER(maxsockets_change, tcp_zone_change, NULL, 1569 EVENTHANDLER_PRI_ANY); 1570 1571 tcp_inp_lro_direct_queue = counter_u64_alloc(M_WAITOK); 1572 tcp_inp_lro_wokeup_queue = counter_u64_alloc(M_WAITOK); 1573 tcp_inp_lro_compressed = counter_u64_alloc(M_WAITOK); 1574 tcp_inp_lro_locks_taken = counter_u64_alloc(M_WAITOK); 1575 tcp_extra_mbuf = counter_u64_alloc(M_WAITOK); 1576 tcp_would_have_but = counter_u64_alloc(M_WAITOK); 1577 tcp_comp_total = counter_u64_alloc(M_WAITOK); 1578 tcp_uncomp_total = counter_u64_alloc(M_WAITOK); 1579 tcp_bad_csums = counter_u64_alloc(M_WAITOK); 1580 #ifdef TCPPCAP 1581 tcp_pcap_init(); 1582 #endif 1583 } 1584 1585 #ifdef VIMAGE 1586 static void 1587 tcp_destroy(void *unused __unused) 1588 { 1589 int n; 1590 #ifdef TCP_HHOOK 1591 int error; 1592 #endif 1593 1594 /* 1595 * All our processes are gone, all our sockets should be cleaned 1596 * up, which means, we should be past the tcp_discardcb() calls. 1597 * Sleep to let all tcpcb timers really disappear and cleanup. 1598 */ 1599 for (;;) { 1600 INP_INFO_WLOCK(&V_tcbinfo); 1601 n = V_tcbinfo.ipi_count; 1602 INP_INFO_WUNLOCK(&V_tcbinfo); 1603 if (n == 0) 1604 break; 1605 pause("tcpdes", hz / 10); 1606 } 1607 tcp_hc_destroy(); 1608 syncache_destroy(); 1609 tcp_tw_destroy(); 1610 in_pcbinfo_destroy(&V_tcbinfo); 1611 /* tcp_discardcb() clears the sack_holes up. */ 1612 uma_zdestroy(V_sack_hole_zone); 1613 uma_zdestroy(V_tcpcb_zone); 1614 1615 /* 1616 * Cannot free the zone until all tcpcbs are released as we attach 1617 * the allocations to them. 1618 */ 1619 tcp_fastopen_destroy(); 1620 1621 COUNTER_ARRAY_FREE(V_tcps_states, TCP_NSTATES); 1622 VNET_PCPUSTAT_FREE(tcpstat); 1623 1624 #ifdef TCP_HHOOK 1625 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_IN]); 1626 if (error != 0) { 1627 printf("%s: WARNING: unable to deregister helper hook " 1628 "type=%d, id=%d: error %d returned\n", __func__, 1629 HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN, error); 1630 } 1631 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_OUT]); 1632 if (error != 0) { 1633 printf("%s: WARNING: unable to deregister helper hook " 1634 "type=%d, id=%d: error %d returned\n", __func__, 1635 HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT, error); 1636 } 1637 #endif 1638 } 1639 VNET_SYSUNINIT(tcp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, tcp_destroy, NULL); 1640 #endif 1641 1642 void 1643 tcp_fini(void *xtp) 1644 { 1645 1646 } 1647 1648 /* 1649 * Fill in the IP and TCP headers for an outgoing packet, given the tcpcb. 1650 * tcp_template used to store this data in mbufs, but we now recopy it out 1651 * of the tcpcb each time to conserve mbufs. 1652 */ 1653 void 1654 tcpip_fillheaders(struct inpcb *inp, uint16_t port, void *ip_ptr, void *tcp_ptr) 1655 { 1656 struct tcphdr *th = (struct tcphdr *)tcp_ptr; 1657 1658 INP_WLOCK_ASSERT(inp); 1659 1660 #ifdef INET6 1661 if ((inp->inp_vflag & INP_IPV6) != 0) { 1662 struct ip6_hdr *ip6; 1663 1664 ip6 = (struct ip6_hdr *)ip_ptr; 1665 ip6->ip6_flow = (ip6->ip6_flow & ~IPV6_FLOWINFO_MASK) | 1666 (inp->inp_flow & IPV6_FLOWINFO_MASK); 1667 ip6->ip6_vfc = (ip6->ip6_vfc & ~IPV6_VERSION_MASK) | 1668 (IPV6_VERSION & IPV6_VERSION_MASK); 1669 if (port == 0) 1670 ip6->ip6_nxt = IPPROTO_TCP; 1671 else 1672 ip6->ip6_nxt = IPPROTO_UDP; 1673 ip6->ip6_plen = htons(sizeof(struct tcphdr)); 1674 ip6->ip6_src = inp->in6p_laddr; 1675 ip6->ip6_dst = inp->in6p_faddr; 1676 } 1677 #endif /* INET6 */ 1678 #if defined(INET6) && defined(INET) 1679 else 1680 #endif 1681 #ifdef INET 1682 { 1683 struct ip *ip; 1684 1685 ip = (struct ip *)ip_ptr; 1686 ip->ip_v = IPVERSION; 1687 ip->ip_hl = 5; 1688 ip->ip_tos = inp->inp_ip_tos; 1689 ip->ip_len = 0; 1690 ip->ip_id = 0; 1691 ip->ip_off = 0; 1692 ip->ip_ttl = inp->inp_ip_ttl; 1693 ip->ip_sum = 0; 1694 if (port == 0) 1695 ip->ip_p = IPPROTO_TCP; 1696 else 1697 ip->ip_p = IPPROTO_UDP; 1698 ip->ip_src = inp->inp_laddr; 1699 ip->ip_dst = inp->inp_faddr; 1700 } 1701 #endif /* INET */ 1702 th->th_sport = inp->inp_lport; 1703 th->th_dport = inp->inp_fport; 1704 th->th_seq = 0; 1705 th->th_ack = 0; 1706 th->th_x2 = 0; 1707 th->th_off = 5; 1708 th->th_flags = 0; 1709 th->th_win = 0; 1710 th->th_urp = 0; 1711 th->th_sum = 0; /* in_pseudo() is called later for ipv4 */ 1712 } 1713 1714 /* 1715 * Create template to be used to send tcp packets on a connection. 1716 * Allocates an mbuf and fills in a skeletal tcp/ip header. The only 1717 * use for this function is in keepalives, which use tcp_respond. 1718 */ 1719 struct tcptemp * 1720 tcpip_maketemplate(struct inpcb *inp) 1721 { 1722 struct tcptemp *t; 1723 1724 t = malloc(sizeof(*t), M_TEMP, M_NOWAIT); 1725 if (t == NULL) 1726 return (NULL); 1727 tcpip_fillheaders(inp, 0, (void *)&t->tt_ipgen, (void *)&t->tt_t); 1728 return (t); 1729 } 1730 1731 /* 1732 * Send a single message to the TCP at address specified by 1733 * the given TCP/IP header. If m == NULL, then we make a copy 1734 * of the tcpiphdr at th and send directly to the addressed host. 1735 * This is used to force keep alive messages out using the TCP 1736 * template for a connection. If flags are given then we send 1737 * a message back to the TCP which originated the segment th, 1738 * and discard the mbuf containing it and any other attached mbufs. 1739 * 1740 * In any case the ack and sequence number of the transmitted 1741 * segment are as specified by the parameters. 1742 * 1743 * NOTE: If m != NULL, then th must point to *inside* the mbuf. 1744 */ 1745 void 1746 tcp_respond(struct tcpcb *tp, void *ipgen, struct tcphdr *th, struct mbuf *m, 1747 tcp_seq ack, tcp_seq seq, int flags) 1748 { 1749 struct tcpopt to; 1750 struct inpcb *inp; 1751 struct ip *ip; 1752 struct mbuf *optm; 1753 struct udphdr *uh = NULL; 1754 struct tcphdr *nth; 1755 struct tcp_log_buffer *lgb; 1756 u_char *optp; 1757 #ifdef INET6 1758 struct ip6_hdr *ip6; 1759 int isipv6; 1760 #endif /* INET6 */ 1761 int optlen, tlen, win, ulen; 1762 bool incl_opts; 1763 uint16_t port; 1764 int output_ret; 1765 #ifdef INVARIANTS 1766 int thflags = th->th_flags; 1767 #endif 1768 1769 KASSERT(tp != NULL || m != NULL, ("tcp_respond: tp and m both NULL")); 1770 NET_EPOCH_ASSERT(); 1771 1772 #ifdef INET6 1773 isipv6 = ((struct ip *)ipgen)->ip_v == (IPV6_VERSION >> 4); 1774 ip6 = ipgen; 1775 #endif /* INET6 */ 1776 ip = ipgen; 1777 1778 if (tp != NULL) { 1779 inp = tp->t_inpcb; 1780 KASSERT(inp != NULL, ("tcp control block w/o inpcb")); 1781 INP_LOCK_ASSERT(inp); 1782 } else 1783 inp = NULL; 1784 1785 if (m != NULL) { 1786 #ifdef INET6 1787 if (isipv6 && ip6 && (ip6->ip6_nxt == IPPROTO_UDP)) 1788 port = m->m_pkthdr.tcp_tun_port; 1789 else 1790 #endif 1791 if (ip && (ip->ip_p == IPPROTO_UDP)) 1792 port = m->m_pkthdr.tcp_tun_port; 1793 else 1794 port = 0; 1795 } else 1796 port = tp->t_port; 1797 1798 incl_opts = false; 1799 win = 0; 1800 if (tp != NULL) { 1801 if (!(flags & TH_RST)) { 1802 win = sbspace(&inp->inp_socket->so_rcv); 1803 if (win > TCP_MAXWIN << tp->rcv_scale) 1804 win = TCP_MAXWIN << tp->rcv_scale; 1805 } 1806 if ((tp->t_flags & TF_NOOPT) == 0) 1807 incl_opts = true; 1808 } 1809 if (m == NULL) { 1810 m = m_gethdr(M_NOWAIT, MT_DATA); 1811 if (m == NULL) 1812 return; 1813 m->m_data += max_linkhdr; 1814 #ifdef INET6 1815 if (isipv6) { 1816 bcopy((caddr_t)ip6, mtod(m, caddr_t), 1817 sizeof(struct ip6_hdr)); 1818 ip6 = mtod(m, struct ip6_hdr *); 1819 nth = (struct tcphdr *)(ip6 + 1); 1820 if (port) { 1821 /* Insert a UDP header */ 1822 uh = (struct udphdr *)nth; 1823 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1824 uh->uh_dport = port; 1825 nth = (struct tcphdr *)(uh + 1); 1826 } 1827 } else 1828 #endif /* INET6 */ 1829 { 1830 bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip)); 1831 ip = mtod(m, struct ip *); 1832 nth = (struct tcphdr *)(ip + 1); 1833 if (port) { 1834 /* Insert a UDP header */ 1835 uh = (struct udphdr *)nth; 1836 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1837 uh->uh_dport = port; 1838 nth = (struct tcphdr *)(uh + 1); 1839 } 1840 } 1841 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr)); 1842 flags = TH_ACK; 1843 } else if ((!M_WRITABLE(m)) || (port != 0)) { 1844 struct mbuf *n; 1845 1846 /* Can't reuse 'm', allocate a new mbuf. */ 1847 n = m_gethdr(M_NOWAIT, MT_DATA); 1848 if (n == NULL) { 1849 m_freem(m); 1850 return; 1851 } 1852 1853 if (!m_dup_pkthdr(n, m, M_NOWAIT)) { 1854 m_freem(m); 1855 m_freem(n); 1856 return; 1857 } 1858 1859 n->m_data += max_linkhdr; 1860 /* m_len is set later */ 1861 #define xchg(a,b,type) { type t; t=a; a=b; b=t; } 1862 #ifdef INET6 1863 if (isipv6) { 1864 bcopy((caddr_t)ip6, mtod(n, caddr_t), 1865 sizeof(struct ip6_hdr)); 1866 ip6 = mtod(n, struct ip6_hdr *); 1867 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); 1868 nth = (struct tcphdr *)(ip6 + 1); 1869 if (port) { 1870 /* Insert a UDP header */ 1871 uh = (struct udphdr *)nth; 1872 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1873 uh->uh_dport = port; 1874 nth = (struct tcphdr *)(uh + 1); 1875 } 1876 } else 1877 #endif /* INET6 */ 1878 { 1879 bcopy((caddr_t)ip, mtod(n, caddr_t), sizeof(struct ip)); 1880 ip = mtod(n, struct ip *); 1881 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t); 1882 nth = (struct tcphdr *)(ip + 1); 1883 if (port) { 1884 /* Insert a UDP header */ 1885 uh = (struct udphdr *)nth; 1886 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1887 uh->uh_dport = port; 1888 nth = (struct tcphdr *)(uh + 1); 1889 } 1890 } 1891 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr)); 1892 xchg(nth->th_dport, nth->th_sport, uint16_t); 1893 th = nth; 1894 m_freem(m); 1895 m = n; 1896 } else { 1897 /* 1898 * reuse the mbuf. 1899 * XXX MRT We inherit the FIB, which is lucky. 1900 */ 1901 m_freem(m->m_next); 1902 m->m_next = NULL; 1903 m->m_data = (caddr_t)ipgen; 1904 /* m_len is set later */ 1905 #ifdef INET6 1906 if (isipv6) { 1907 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); 1908 nth = (struct tcphdr *)(ip6 + 1); 1909 } else 1910 #endif /* INET6 */ 1911 { 1912 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t); 1913 nth = (struct tcphdr *)(ip + 1); 1914 } 1915 if (th != nth) { 1916 /* 1917 * this is usually a case when an extension header 1918 * exists between the IPv6 header and the 1919 * TCP header. 1920 */ 1921 nth->th_sport = th->th_sport; 1922 nth->th_dport = th->th_dport; 1923 } 1924 xchg(nth->th_dport, nth->th_sport, uint16_t); 1925 #undef xchg 1926 } 1927 tlen = 0; 1928 #ifdef INET6 1929 if (isipv6) 1930 tlen = sizeof (struct ip6_hdr) + sizeof (struct tcphdr); 1931 #endif 1932 #if defined(INET) && defined(INET6) 1933 else 1934 #endif 1935 #ifdef INET 1936 tlen = sizeof (struct tcpiphdr); 1937 #endif 1938 if (port) 1939 tlen += sizeof (struct udphdr); 1940 #ifdef INVARIANTS 1941 m->m_len = 0; 1942 KASSERT(M_TRAILINGSPACE(m) >= tlen, 1943 ("Not enough trailing space for message (m=%p, need=%d, have=%ld)", 1944 m, tlen, (long)M_TRAILINGSPACE(m))); 1945 #endif 1946 m->m_len = tlen; 1947 to.to_flags = 0; 1948 if (incl_opts) { 1949 /* Make sure we have room. */ 1950 if (M_TRAILINGSPACE(m) < TCP_MAXOLEN) { 1951 m->m_next = m_get(M_NOWAIT, MT_DATA); 1952 if (m->m_next) { 1953 optp = mtod(m->m_next, u_char *); 1954 optm = m->m_next; 1955 } else 1956 incl_opts = false; 1957 } else { 1958 optp = (u_char *) (nth + 1); 1959 optm = m; 1960 } 1961 } 1962 if (incl_opts) { 1963 /* Timestamps. */ 1964 if (tp->t_flags & TF_RCVD_TSTMP) { 1965 to.to_tsval = tcp_ts_getticks() + tp->ts_offset; 1966 to.to_tsecr = tp->ts_recent; 1967 to.to_flags |= TOF_TS; 1968 } 1969 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 1970 /* TCP-MD5 (RFC2385). */ 1971 if (tp->t_flags & TF_SIGNATURE) 1972 to.to_flags |= TOF_SIGNATURE; 1973 #endif 1974 /* Add the options. */ 1975 tlen += optlen = tcp_addoptions(&to, optp); 1976 1977 /* Update m_len in the correct mbuf. */ 1978 optm->m_len += optlen; 1979 } else 1980 optlen = 0; 1981 #ifdef INET6 1982 if (isipv6) { 1983 if (uh) { 1984 ulen = tlen - sizeof(struct ip6_hdr); 1985 uh->uh_ulen = htons(ulen); 1986 } 1987 ip6->ip6_flow = 0; 1988 ip6->ip6_vfc = IPV6_VERSION; 1989 if (port) 1990 ip6->ip6_nxt = IPPROTO_UDP; 1991 else 1992 ip6->ip6_nxt = IPPROTO_TCP; 1993 ip6->ip6_plen = htons(tlen - sizeof(*ip6)); 1994 } 1995 #endif 1996 #if defined(INET) && defined(INET6) 1997 else 1998 #endif 1999 #ifdef INET 2000 { 2001 if (uh) { 2002 ulen = tlen - sizeof(struct ip); 2003 uh->uh_ulen = htons(ulen); 2004 } 2005 ip->ip_len = htons(tlen); 2006 ip->ip_ttl = V_ip_defttl; 2007 if (port) { 2008 ip->ip_p = IPPROTO_UDP; 2009 } else { 2010 ip->ip_p = IPPROTO_TCP; 2011 } 2012 if (V_path_mtu_discovery) 2013 ip->ip_off |= htons(IP_DF); 2014 } 2015 #endif 2016 m->m_pkthdr.len = tlen; 2017 m->m_pkthdr.rcvif = NULL; 2018 #ifdef MAC 2019 if (inp != NULL) { 2020 /* 2021 * Packet is associated with a socket, so allow the 2022 * label of the response to reflect the socket label. 2023 */ 2024 INP_LOCK_ASSERT(inp); 2025 mac_inpcb_create_mbuf(inp, m); 2026 } else { 2027 /* 2028 * Packet is not associated with a socket, so possibly 2029 * update the label in place. 2030 */ 2031 mac_netinet_tcp_reply(m); 2032 } 2033 #endif 2034 nth->th_seq = htonl(seq); 2035 nth->th_ack = htonl(ack); 2036 nth->th_x2 = 0; 2037 nth->th_off = (sizeof (struct tcphdr) + optlen) >> 2; 2038 nth->th_flags = flags; 2039 if (tp != NULL) 2040 nth->th_win = htons((u_short) (win >> tp->rcv_scale)); 2041 else 2042 nth->th_win = htons((u_short)win); 2043 nth->th_urp = 0; 2044 2045 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 2046 if (to.to_flags & TOF_SIGNATURE) { 2047 if (!TCPMD5_ENABLED() || 2048 TCPMD5_OUTPUT(m, nth, to.to_signature) != 0) { 2049 m_freem(m); 2050 return; 2051 } 2052 } 2053 #endif 2054 2055 #ifdef INET6 2056 if (isipv6) { 2057 if (port) { 2058 m->m_pkthdr.csum_flags = CSUM_UDP_IPV6; 2059 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 2060 uh->uh_sum = in6_cksum_pseudo(ip6, ulen, IPPROTO_UDP, 0); 2061 nth->th_sum = 0; 2062 } else { 2063 m->m_pkthdr.csum_flags = CSUM_TCP_IPV6; 2064 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); 2065 nth->th_sum = in6_cksum_pseudo(ip6, 2066 tlen - sizeof(struct ip6_hdr), IPPROTO_TCP, 0); 2067 } 2068 ip6->ip6_hlim = in6_selecthlim(tp != NULL ? tp->t_inpcb : 2069 NULL, NULL); 2070 } 2071 #endif /* INET6 */ 2072 #if defined(INET6) && defined(INET) 2073 else 2074 #endif 2075 #ifdef INET 2076 { 2077 if (port) { 2078 uh->uh_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, 2079 htons(ulen + IPPROTO_UDP)); 2080 m->m_pkthdr.csum_flags = CSUM_UDP; 2081 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 2082 nth->th_sum = 0; 2083 } else { 2084 m->m_pkthdr.csum_flags = CSUM_TCP; 2085 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); 2086 nth->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, 2087 htons((u_short)(tlen - sizeof(struct ip) + ip->ip_p))); 2088 } 2089 } 2090 #endif /* INET */ 2091 #ifdef TCPDEBUG 2092 if (tp == NULL || (inp->inp_socket->so_options & SO_DEBUG)) 2093 tcp_trace(TA_OUTPUT, 0, tp, mtod(m, void *), th, 0); 2094 #endif 2095 TCP_PROBE3(debug__output, tp, th, m); 2096 if (flags & TH_RST) 2097 TCP_PROBE5(accept__refused, NULL, NULL, m, tp, nth); 2098 lgb = NULL; 2099 if ((tp != NULL) && (tp->t_logstate != TCP_LOG_STATE_OFF)) { 2100 if (INP_WLOCKED(inp)) { 2101 union tcp_log_stackspecific log; 2102 struct timeval tv; 2103 2104 memset(&log.u_bbr, 0, sizeof(log.u_bbr)); 2105 log.u_bbr.inhpts = tp->t_inpcb->inp_in_hpts; 2106 log.u_bbr.ininput = tp->t_inpcb->inp_in_dropq; 2107 log.u_bbr.flex8 = 4; 2108 log.u_bbr.pkts_out = tp->t_maxseg; 2109 log.u_bbr.timeStamp = tcp_get_usecs(&tv); 2110 log.u_bbr.delivered = 0; 2111 lgb = tcp_log_event_(tp, nth, NULL, NULL, TCP_LOG_OUT, 2112 ERRNO_UNK, 0, &log, false, NULL, NULL, 0, &tv); 2113 } else { 2114 /* 2115 * We can not log the packet, since we only own the 2116 * read lock, but a write lock is needed. The read lock 2117 * is not upgraded to a write lock, since only getting 2118 * the read lock was done intentionally to improve the 2119 * handling of SYN flooding attacks. 2120 * This happens only for pure SYN segments received in 2121 * the initial CLOSED state, or received in a more 2122 * advanced state than listen and the UDP encapsulation 2123 * port is unexpected. 2124 * The incoming SYN segments do not really belong to 2125 * the TCP connection and the handling does not change 2126 * the state of the TCP connection. Therefore, the 2127 * sending of the RST segments is not logged. Please 2128 * note that also the incoming SYN segments are not 2129 * logged. 2130 * 2131 * The following code ensures that the above description 2132 * is and stays correct. 2133 */ 2134 KASSERT((thflags & (TH_ACK|TH_SYN)) == TH_SYN && 2135 (tp->t_state == TCPS_CLOSED || 2136 (tp->t_state > TCPS_LISTEN && tp->t_port != port)), 2137 ("%s: Logging of TCP segment with flags 0x%b and " 2138 "UDP encapsulation port %u skipped in state %s", 2139 __func__, thflags, PRINT_TH_FLAGS, 2140 ntohs(port), tcpstates[tp->t_state])); 2141 } 2142 } 2143 2144 #ifdef INET6 2145 if (isipv6) { 2146 TCP_PROBE5(send, NULL, tp, ip6, tp, nth); 2147 output_ret = ip6_output(m, NULL, NULL, 0, NULL, NULL, inp); 2148 } 2149 #endif /* INET6 */ 2150 #if defined(INET) && defined(INET6) 2151 else 2152 #endif 2153 #ifdef INET 2154 { 2155 TCP_PROBE5(send, NULL, tp, ip, tp, nth); 2156 output_ret = ip_output(m, NULL, NULL, 0, NULL, inp); 2157 } 2158 #endif 2159 if (lgb != NULL) 2160 lgb->tlb_errno = output_ret; 2161 } 2162 2163 /* 2164 * Create a new TCP control block, making an 2165 * empty reassembly queue and hooking it to the argument 2166 * protocol control block. The `inp' parameter must have 2167 * come from the zone allocator set up in tcp_init(). 2168 */ 2169 struct tcpcb * 2170 tcp_newtcpcb(struct inpcb *inp) 2171 { 2172 struct tcpcb_mem *tm; 2173 struct tcpcb *tp; 2174 #ifdef INET6 2175 int isipv6 = (inp->inp_vflag & INP_IPV6) != 0; 2176 #endif /* INET6 */ 2177 2178 tm = uma_zalloc(V_tcpcb_zone, M_NOWAIT | M_ZERO); 2179 if (tm == NULL) 2180 return (NULL); 2181 tp = &tm->tcb; 2182 2183 /* Initialise cc_var struct for this tcpcb. */ 2184 tp->ccv = &tm->ccv; 2185 tp->ccv->type = IPPROTO_TCP; 2186 tp->ccv->ccvc.tcp = tp; 2187 rw_rlock(&tcp_function_lock); 2188 tp->t_fb = tcp_func_set_ptr; 2189 refcount_acquire(&tp->t_fb->tfb_refcnt); 2190 rw_runlock(&tcp_function_lock); 2191 /* 2192 * Use the current system default CC algorithm. 2193 */ 2194 CC_LIST_RLOCK(); 2195 KASSERT(!STAILQ_EMPTY(&cc_list), ("cc_list is empty!")); 2196 CC_ALGO(tp) = CC_DEFAULT_ALGO(); 2197 CC_LIST_RUNLOCK(); 2198 2199 /* 2200 * The tcpcb will hold a reference on its inpcb until tcp_discardcb() 2201 * is called. 2202 */ 2203 in_pcbref(inp); /* Reference for tcpcb */ 2204 tp->t_inpcb = inp; 2205 2206 if (CC_ALGO(tp)->cb_init != NULL) 2207 if (CC_ALGO(tp)->cb_init(tp->ccv, NULL) > 0) { 2208 if (tp->t_fb->tfb_tcp_fb_fini) 2209 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); 2210 in_pcbrele_wlocked(inp); 2211 refcount_release(&tp->t_fb->tfb_refcnt); 2212 uma_zfree(V_tcpcb_zone, tm); 2213 return (NULL); 2214 } 2215 2216 #ifdef TCP_HHOOK 2217 tp->osd = &tm->osd; 2218 if (khelp_init_osd(HELPER_CLASS_TCP, tp->osd)) { 2219 if (tp->t_fb->tfb_tcp_fb_fini) 2220 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); 2221 in_pcbrele_wlocked(inp); 2222 refcount_release(&tp->t_fb->tfb_refcnt); 2223 uma_zfree(V_tcpcb_zone, tm); 2224 return (NULL); 2225 } 2226 #endif 2227 2228 #ifdef VIMAGE 2229 tp->t_vnet = inp->inp_vnet; 2230 #endif 2231 tp->t_timers = &tm->tt; 2232 TAILQ_INIT(&tp->t_segq); 2233 tp->t_maxseg = 2234 #ifdef INET6 2235 isipv6 ? V_tcp_v6mssdflt : 2236 #endif /* INET6 */ 2237 V_tcp_mssdflt; 2238 2239 /* Set up our timeouts. */ 2240 callout_init(&tp->t_timers->tt_rexmt, 1); 2241 callout_init(&tp->t_timers->tt_persist, 1); 2242 callout_init(&tp->t_timers->tt_keep, 1); 2243 callout_init(&tp->t_timers->tt_2msl, 1); 2244 callout_init(&tp->t_timers->tt_delack, 1); 2245 2246 if (V_tcp_do_rfc1323) 2247 tp->t_flags = (TF_REQ_SCALE|TF_REQ_TSTMP); 2248 if (V_tcp_do_sack) 2249 tp->t_flags |= TF_SACK_PERMIT; 2250 TAILQ_INIT(&tp->snd_holes); 2251 2252 /* 2253 * Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no 2254 * rtt estimate. Set rttvar so that srtt + 4 * rttvar gives 2255 * reasonable initial retransmit time. 2256 */ 2257 tp->t_srtt = TCPTV_SRTTBASE; 2258 tp->t_rttvar = ((tcp_rexmit_initial - TCPTV_SRTTBASE) << TCP_RTTVAR_SHIFT) / 4; 2259 tp->t_rttmin = tcp_rexmit_min; 2260 tp->t_rxtcur = tcp_rexmit_initial; 2261 tp->snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT; 2262 tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT; 2263 tp->t_rcvtime = ticks; 2264 /* 2265 * IPv4 TTL initialization is necessary for an IPv6 socket as well, 2266 * because the socket may be bound to an IPv6 wildcard address, 2267 * which may match an IPv4-mapped IPv6 address. 2268 */ 2269 inp->inp_ip_ttl = V_ip_defttl; 2270 inp->inp_ppcb = tp; 2271 #ifdef TCPPCAP 2272 /* 2273 * Init the TCP PCAP queues. 2274 */ 2275 tcp_pcap_tcpcb_init(tp); 2276 #endif 2277 #ifdef TCP_BLACKBOX 2278 /* Initialize the per-TCPCB log data. */ 2279 tcp_log_tcpcbinit(tp); 2280 #endif 2281 tp->t_pacing_rate = -1; 2282 if (tp->t_fb->tfb_tcp_fb_init) { 2283 if ((*tp->t_fb->tfb_tcp_fb_init)(tp)) { 2284 refcount_release(&tp->t_fb->tfb_refcnt); 2285 in_pcbrele_wlocked(inp); 2286 uma_zfree(V_tcpcb_zone, tm); 2287 return (NULL); 2288 } 2289 } 2290 #ifdef STATS 2291 if (V_tcp_perconn_stats_enable == 1) 2292 tp->t_stats = stats_blob_alloc(V_tcp_perconn_stats_dflt_tpl, 0); 2293 #endif 2294 if (V_tcp_do_lrd) 2295 tp->t_flags |= TF_LRD; 2296 return (tp); /* XXX */ 2297 } 2298 2299 /* 2300 * Switch the congestion control algorithm back to Vnet default for any active 2301 * control blocks using an algorithm which is about to go away. If the algorithm 2302 * has a cb_init function and it fails (no memory) then the operation fails and 2303 * the unload will not succeed. 2304 * 2305 */ 2306 int 2307 tcp_ccalgounload(struct cc_algo *unload_algo) 2308 { 2309 struct cc_algo *oldalgo, *newalgo; 2310 struct inpcb *inp; 2311 struct tcpcb *tp; 2312 VNET_ITERATOR_DECL(vnet_iter); 2313 2314 /* 2315 * Check all active control blocks across all network stacks and change 2316 * any that are using "unload_algo" back to its default. If "unload_algo" 2317 * requires cleanup code to be run, call it. 2318 */ 2319 VNET_LIST_RLOCK(); 2320 VNET_FOREACH(vnet_iter) { 2321 CURVNET_SET(vnet_iter); 2322 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, 2323 INPLOOKUP_WLOCKPCB); 2324 /* 2325 * XXXGL: would new accept(2)d connections use algo being 2326 * unloaded? 2327 */ 2328 newalgo = CC_DEFAULT_ALGO(); 2329 while ((inp = inp_next(&inpi)) != NULL) { 2330 /* Important to skip tcptw structs. */ 2331 if (!(inp->inp_flags & INP_TIMEWAIT) && 2332 (tp = intotcpcb(inp)) != NULL) { 2333 /* 2334 * By holding INP_WLOCK here, we are assured 2335 * that the connection is not currently 2336 * executing inside the CC module's functions. 2337 * We attempt to switch to the Vnets default, 2338 * if the init fails then we fail the whole 2339 * operation and the module unload will fail. 2340 */ 2341 if (CC_ALGO(tp) == unload_algo) { 2342 struct cc_var cc_mem; 2343 int err; 2344 2345 oldalgo = CC_ALGO(tp); 2346 memset(&cc_mem, 0, sizeof(cc_mem)); 2347 cc_mem.ccvc.tcp = tp; 2348 if (newalgo->cb_init == NULL) { 2349 /* 2350 * No init we can skip the 2351 * dance around a possible failure. 2352 */ 2353 CC_DATA(tp) = NULL; 2354 goto proceed; 2355 } 2356 err = (newalgo->cb_init)(&cc_mem, NULL); 2357 if (err) { 2358 /* 2359 * Presumably no memory the caller will 2360 * need to try again. 2361 */ 2362 INP_WUNLOCK(inp); 2363 CURVNET_RESTORE(); 2364 VNET_LIST_RUNLOCK(); 2365 return (err); 2366 } 2367 proceed: 2368 if (oldalgo->cb_destroy != NULL) 2369 oldalgo->cb_destroy(tp->ccv); 2370 CC_ALGO(tp) = newalgo; 2371 memcpy(tp->ccv, &cc_mem, sizeof(struct cc_var)); 2372 if (TCPS_HAVEESTABLISHED(tp->t_state) && 2373 (CC_ALGO(tp)->conn_init != NULL)) { 2374 /* Yep run the connection init for the new CC */ 2375 CC_ALGO(tp)->conn_init(tp->ccv); 2376 } 2377 } 2378 } 2379 } 2380 CURVNET_RESTORE(); 2381 } 2382 VNET_LIST_RUNLOCK(); 2383 return (0); 2384 } 2385 2386 /* 2387 * Drop a TCP connection, reporting 2388 * the specified error. If connection is synchronized, 2389 * then send a RST to peer. 2390 */ 2391 struct tcpcb * 2392 tcp_drop(struct tcpcb *tp, int errno) 2393 { 2394 struct socket *so = tp->t_inpcb->inp_socket; 2395 2396 NET_EPOCH_ASSERT(); 2397 INP_WLOCK_ASSERT(tp->t_inpcb); 2398 2399 if (TCPS_HAVERCVDSYN(tp->t_state)) { 2400 tcp_state_change(tp, TCPS_CLOSED); 2401 (void) tp->t_fb->tfb_tcp_output(tp); 2402 TCPSTAT_INC(tcps_drops); 2403 } else 2404 TCPSTAT_INC(tcps_conndrops); 2405 if (errno == ETIMEDOUT && tp->t_softerror) 2406 errno = tp->t_softerror; 2407 so->so_error = errno; 2408 return (tcp_close(tp)); 2409 } 2410 2411 void 2412 tcp_discardcb(struct tcpcb *tp) 2413 { 2414 struct inpcb *inp = tp->t_inpcb; 2415 2416 INP_WLOCK_ASSERT(inp); 2417 2418 /* 2419 * Make sure that all of our timers are stopped before we delete the 2420 * PCB. 2421 * 2422 * If stopping a timer fails, we schedule a discard function in same 2423 * callout, and the last discard function called will take care of 2424 * deleting the tcpcb. 2425 */ 2426 tp->t_timers->tt_draincnt = 0; 2427 tcp_timer_stop(tp, TT_REXMT); 2428 tcp_timer_stop(tp, TT_PERSIST); 2429 tcp_timer_stop(tp, TT_KEEP); 2430 tcp_timer_stop(tp, TT_2MSL); 2431 tcp_timer_stop(tp, TT_DELACK); 2432 if (tp->t_fb->tfb_tcp_timer_stop_all) { 2433 /* 2434 * Call the stop-all function of the methods, 2435 * this function should call the tcp_timer_stop() 2436 * method with each of the function specific timeouts. 2437 * That stop will be called via the tfb_tcp_timer_stop() 2438 * which should use the async drain function of the 2439 * callout system (see tcp_var.h). 2440 */ 2441 tp->t_fb->tfb_tcp_timer_stop_all(tp); 2442 } 2443 2444 /* free the reassembly queue, if any */ 2445 tcp_reass_flush(tp); 2446 2447 #ifdef TCP_OFFLOAD 2448 /* Disconnect offload device, if any. */ 2449 if (tp->t_flags & TF_TOE) 2450 tcp_offload_detach(tp); 2451 #endif 2452 2453 tcp_free_sackholes(tp); 2454 2455 #ifdef TCPPCAP 2456 /* Free the TCP PCAP queues. */ 2457 tcp_pcap_drain(&(tp->t_inpkts)); 2458 tcp_pcap_drain(&(tp->t_outpkts)); 2459 #endif 2460 2461 /* Allow the CC algorithm to clean up after itself. */ 2462 if (CC_ALGO(tp)->cb_destroy != NULL) 2463 CC_ALGO(tp)->cb_destroy(tp->ccv); 2464 CC_DATA(tp) = NULL; 2465 2466 #ifdef TCP_HHOOK 2467 khelp_destroy_osd(tp->osd); 2468 #endif 2469 #ifdef STATS 2470 stats_blob_destroy(tp->t_stats); 2471 #endif 2472 2473 CC_ALGO(tp) = NULL; 2474 inp->inp_ppcb = NULL; 2475 if (tp->t_timers->tt_draincnt == 0) { 2476 bool released __diagused; 2477 2478 released = tcp_freecb(tp); 2479 KASSERT(!released, ("%s: inp %p should not have been released " 2480 "here", __func__, inp)); 2481 } 2482 } 2483 2484 bool 2485 tcp_freecb(struct tcpcb *tp) 2486 { 2487 struct inpcb *inp = tp->t_inpcb; 2488 struct socket *so = inp->inp_socket; 2489 #ifdef INET6 2490 bool isipv6 = (inp->inp_vflag & INP_IPV6) != 0; 2491 #endif 2492 2493 INP_WLOCK_ASSERT(inp); 2494 MPASS(tp->t_timers->tt_draincnt == 0); 2495 2496 /* We own the last reference on tcpcb, let's free it. */ 2497 #ifdef TCP_BLACKBOX 2498 tcp_log_tcpcbfini(tp); 2499 #endif 2500 TCPSTATES_DEC(tp->t_state); 2501 if (tp->t_fb->tfb_tcp_fb_fini) 2502 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); 2503 2504 /* 2505 * If we got enough samples through the srtt filter, 2506 * save the rtt and rttvar in the routing entry. 2507 * 'Enough' is arbitrarily defined as 4 rtt samples. 2508 * 4 samples is enough for the srtt filter to converge 2509 * to within enough % of the correct value; fewer samples 2510 * and we could save a bogus rtt. The danger is not high 2511 * as tcp quickly recovers from everything. 2512 * XXX: Works very well but needs some more statistics! 2513 * 2514 * XXXRRS: Updating must be after the stack fini() since 2515 * that may be converting some internal representation of 2516 * say srtt etc into the general one used by other stacks. 2517 * Lets also at least protect against the so being NULL 2518 * as RW stated below. 2519 */ 2520 if ((tp->t_rttupdated >= 4) && (so != NULL)) { 2521 struct hc_metrics_lite metrics; 2522 uint32_t ssthresh; 2523 2524 bzero(&metrics, sizeof(metrics)); 2525 /* 2526 * Update the ssthresh always when the conditions below 2527 * are satisfied. This gives us better new start value 2528 * for the congestion avoidance for new connections. 2529 * ssthresh is only set if packet loss occurred on a session. 2530 * 2531 * XXXRW: 'so' may be NULL here, and/or socket buffer may be 2532 * being torn down. Ideally this code would not use 'so'. 2533 */ 2534 ssthresh = tp->snd_ssthresh; 2535 if (ssthresh != 0 && ssthresh < so->so_snd.sb_hiwat / 2) { 2536 /* 2537 * convert the limit from user data bytes to 2538 * packets then to packet data bytes. 2539 */ 2540 ssthresh = (ssthresh + tp->t_maxseg / 2) / tp->t_maxseg; 2541 if (ssthresh < 2) 2542 ssthresh = 2; 2543 ssthresh *= (tp->t_maxseg + 2544 #ifdef INET6 2545 (isipv6 ? sizeof (struct ip6_hdr) + 2546 sizeof (struct tcphdr) : 2547 #endif 2548 sizeof (struct tcpiphdr) 2549 #ifdef INET6 2550 ) 2551 #endif 2552 ); 2553 } else 2554 ssthresh = 0; 2555 metrics.rmx_ssthresh = ssthresh; 2556 2557 metrics.rmx_rtt = tp->t_srtt; 2558 metrics.rmx_rttvar = tp->t_rttvar; 2559 metrics.rmx_cwnd = tp->snd_cwnd; 2560 metrics.rmx_sendpipe = 0; 2561 metrics.rmx_recvpipe = 0; 2562 2563 tcp_hc_update(&inp->inp_inc, &metrics); 2564 } 2565 2566 refcount_release(&tp->t_fb->tfb_refcnt); 2567 uma_zfree(V_tcpcb_zone, tp); 2568 2569 return (in_pcbrele_wlocked(inp)); 2570 } 2571 2572 /* 2573 * Attempt to close a TCP control block, marking it as dropped, and freeing 2574 * the socket if we hold the only reference. 2575 */ 2576 struct tcpcb * 2577 tcp_close(struct tcpcb *tp) 2578 { 2579 struct inpcb *inp = tp->t_inpcb; 2580 struct socket *so; 2581 2582 INP_WLOCK_ASSERT(inp); 2583 2584 #ifdef TCP_OFFLOAD 2585 if (tp->t_state == TCPS_LISTEN) 2586 tcp_offload_listen_stop(tp); 2587 #endif 2588 /* 2589 * This releases the TFO pending counter resource for TFO listen 2590 * sockets as well as passively-created TFO sockets that transition 2591 * from SYN_RECEIVED to CLOSED. 2592 */ 2593 if (tp->t_tfo_pending) { 2594 tcp_fastopen_decrement_counter(tp->t_tfo_pending); 2595 tp->t_tfo_pending = NULL; 2596 } 2597 #ifdef TCPHPTS 2598 tcp_hpts_remove(inp, HPTS_REMOVE_ALL); 2599 #endif 2600 in_pcbdrop(inp); 2601 TCPSTAT_INC(tcps_closed); 2602 if (tp->t_state != TCPS_CLOSED) 2603 tcp_state_change(tp, TCPS_CLOSED); 2604 KASSERT(inp->inp_socket != NULL, ("tcp_close: inp_socket NULL")); 2605 so = inp->inp_socket; 2606 soisdisconnected(so); 2607 if (inp->inp_flags & INP_SOCKREF) { 2608 KASSERT(so->so_state & SS_PROTOREF, 2609 ("tcp_close: !SS_PROTOREF")); 2610 inp->inp_flags &= ~INP_SOCKREF; 2611 INP_WUNLOCK(inp); 2612 SOCK_LOCK(so); 2613 so->so_state &= ~SS_PROTOREF; 2614 sofree(so); 2615 return (NULL); 2616 } 2617 return (tp); 2618 } 2619 2620 void 2621 tcp_drain(void) 2622 { 2623 VNET_ITERATOR_DECL(vnet_iter); 2624 2625 if (!do_tcpdrain) 2626 return; 2627 2628 VNET_LIST_RLOCK_NOSLEEP(); 2629 VNET_FOREACH(vnet_iter) { 2630 CURVNET_SET(vnet_iter); 2631 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, 2632 INPLOOKUP_WLOCKPCB); 2633 struct inpcb *inpb; 2634 struct tcpcb *tcpb; 2635 2636 /* 2637 * Walk the tcpbs, if existing, and flush the reassembly queue, 2638 * if there is one... 2639 * XXX: The "Net/3" implementation doesn't imply that the TCP 2640 * reassembly queue should be flushed, but in a situation 2641 * where we're really low on mbufs, this is potentially 2642 * useful. 2643 */ 2644 while ((inpb = inp_next(&inpi)) != NULL) { 2645 if (inpb->inp_flags & INP_TIMEWAIT) 2646 continue; 2647 if ((tcpb = intotcpcb(inpb)) != NULL) { 2648 tcp_reass_flush(tcpb); 2649 tcp_clean_sackreport(tcpb); 2650 #ifdef TCP_BLACKBOX 2651 tcp_log_drain(tcpb); 2652 #endif 2653 #ifdef TCPPCAP 2654 if (tcp_pcap_aggressive_free) { 2655 /* Free the TCP PCAP queues. */ 2656 tcp_pcap_drain(&(tcpb->t_inpkts)); 2657 tcp_pcap_drain(&(tcpb->t_outpkts)); 2658 } 2659 #endif 2660 } 2661 } 2662 CURVNET_RESTORE(); 2663 } 2664 VNET_LIST_RUNLOCK_NOSLEEP(); 2665 } 2666 2667 /* 2668 * Notify a tcp user of an asynchronous error; 2669 * store error as soft error, but wake up user 2670 * (for now, won't do anything until can select for soft error). 2671 * 2672 * Do not wake up user since there currently is no mechanism for 2673 * reporting soft errors (yet - a kqueue filter may be added). 2674 */ 2675 static struct inpcb * 2676 tcp_notify(struct inpcb *inp, int error) 2677 { 2678 struct tcpcb *tp; 2679 2680 INP_WLOCK_ASSERT(inp); 2681 2682 if ((inp->inp_flags & INP_TIMEWAIT) || 2683 (inp->inp_flags & INP_DROPPED)) 2684 return (inp); 2685 2686 tp = intotcpcb(inp); 2687 KASSERT(tp != NULL, ("tcp_notify: tp == NULL")); 2688 2689 /* 2690 * Ignore some errors if we are hooked up. 2691 * If connection hasn't completed, has retransmitted several times, 2692 * and receives a second error, give up now. This is better 2693 * than waiting a long time to establish a connection that 2694 * can never complete. 2695 */ 2696 if (tp->t_state == TCPS_ESTABLISHED && 2697 (error == EHOSTUNREACH || error == ENETUNREACH || 2698 error == EHOSTDOWN)) { 2699 if (inp->inp_route.ro_nh) { 2700 NH_FREE(inp->inp_route.ro_nh); 2701 inp->inp_route.ro_nh = (struct nhop_object *)NULL; 2702 } 2703 return (inp); 2704 } else if (tp->t_state < TCPS_ESTABLISHED && tp->t_rxtshift > 3 && 2705 tp->t_softerror) { 2706 tp = tcp_drop(tp, error); 2707 if (tp != NULL) 2708 return (inp); 2709 else 2710 return (NULL); 2711 } else { 2712 tp->t_softerror = error; 2713 return (inp); 2714 } 2715 #if 0 2716 wakeup( &so->so_timeo); 2717 sorwakeup(so); 2718 sowwakeup(so); 2719 #endif 2720 } 2721 2722 static int 2723 tcp_pcblist(SYSCTL_HANDLER_ARGS) 2724 { 2725 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, 2726 INPLOOKUP_RLOCKPCB); 2727 struct xinpgen xig; 2728 struct inpcb *inp; 2729 int error; 2730 2731 if (req->newptr != NULL) 2732 return (EPERM); 2733 2734 if (req->oldptr == NULL) { 2735 int n; 2736 2737 n = V_tcbinfo.ipi_count + 2738 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); 2739 n += imax(n / 8, 10); 2740 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xtcpcb); 2741 return (0); 2742 } 2743 2744 if ((error = sysctl_wire_old_buffer(req, 0)) != 0) 2745 return (error); 2746 2747 bzero(&xig, sizeof(xig)); 2748 xig.xig_len = sizeof xig; 2749 xig.xig_count = V_tcbinfo.ipi_count + 2750 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); 2751 xig.xig_gen = V_tcbinfo.ipi_gencnt; 2752 xig.xig_sogen = so_gencnt; 2753 error = SYSCTL_OUT(req, &xig, sizeof xig); 2754 if (error) 2755 return (error); 2756 2757 error = syncache_pcblist(req); 2758 if (error) 2759 return (error); 2760 2761 while ((inp = inp_next(&inpi)) != NULL) { 2762 if (inp->inp_gencnt <= xig.xig_gen) { 2763 int crerr; 2764 2765 /* 2766 * XXX: This use of cr_cansee(), introduced with 2767 * TCP state changes, is not quite right, but for 2768 * now, better than nothing. 2769 */ 2770 if (inp->inp_flags & INP_TIMEWAIT) { 2771 if (intotw(inp) != NULL) 2772 crerr = cr_cansee(req->td->td_ucred, 2773 intotw(inp)->tw_cred); 2774 else 2775 crerr = EINVAL; /* Skip this inp. */ 2776 } else 2777 crerr = cr_canseeinpcb(req->td->td_ucred, inp); 2778 if (crerr == 0) { 2779 struct xtcpcb xt; 2780 2781 tcp_inptoxtp(inp, &xt); 2782 error = SYSCTL_OUT(req, &xt, sizeof xt); 2783 if (error) { 2784 INP_RUNLOCK(inp); 2785 break; 2786 } else 2787 continue; 2788 } 2789 } 2790 } 2791 2792 if (!error) { 2793 /* 2794 * Give the user an updated idea of our state. 2795 * If the generation differs from what we told 2796 * her before, she knows that something happened 2797 * while we were processing this request, and it 2798 * might be necessary to retry. 2799 */ 2800 xig.xig_gen = V_tcbinfo.ipi_gencnt; 2801 xig.xig_sogen = so_gencnt; 2802 xig.xig_count = V_tcbinfo.ipi_count + 2803 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); 2804 error = SYSCTL_OUT(req, &xig, sizeof xig); 2805 } 2806 2807 return (error); 2808 } 2809 2810 SYSCTL_PROC(_net_inet_tcp, TCPCTL_PCBLIST, pcblist, 2811 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_NEEDGIANT, 2812 NULL, 0, tcp_pcblist, "S,xtcpcb", 2813 "List of active TCP connections"); 2814 2815 #ifdef INET 2816 static int 2817 tcp_getcred(SYSCTL_HANDLER_ARGS) 2818 { 2819 struct xucred xuc; 2820 struct sockaddr_in addrs[2]; 2821 struct epoch_tracker et; 2822 struct inpcb *inp; 2823 int error; 2824 2825 error = priv_check(req->td, PRIV_NETINET_GETCRED); 2826 if (error) 2827 return (error); 2828 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 2829 if (error) 2830 return (error); 2831 NET_EPOCH_ENTER(et); 2832 inp = in_pcblookup(&V_tcbinfo, addrs[1].sin_addr, addrs[1].sin_port, 2833 addrs[0].sin_addr, addrs[0].sin_port, INPLOOKUP_RLOCKPCB, NULL); 2834 NET_EPOCH_EXIT(et); 2835 if (inp != NULL) { 2836 if (inp->inp_socket == NULL) 2837 error = ENOENT; 2838 if (error == 0) 2839 error = cr_canseeinpcb(req->td->td_ucred, inp); 2840 if (error == 0) 2841 cru2x(inp->inp_cred, &xuc); 2842 INP_RUNLOCK(inp); 2843 } else 2844 error = ENOENT; 2845 if (error == 0) 2846 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 2847 return (error); 2848 } 2849 2850 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, getcred, 2851 CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_NEEDGIANT, 2852 0, 0, tcp_getcred, "S,xucred", 2853 "Get the xucred of a TCP connection"); 2854 #endif /* INET */ 2855 2856 #ifdef INET6 2857 static int 2858 tcp6_getcred(SYSCTL_HANDLER_ARGS) 2859 { 2860 struct epoch_tracker et; 2861 struct xucred xuc; 2862 struct sockaddr_in6 addrs[2]; 2863 struct inpcb *inp; 2864 int error; 2865 #ifdef INET 2866 int mapped = 0; 2867 #endif 2868 2869 error = priv_check(req->td, PRIV_NETINET_GETCRED); 2870 if (error) 2871 return (error); 2872 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 2873 if (error) 2874 return (error); 2875 if ((error = sa6_embedscope(&addrs[0], V_ip6_use_defzone)) != 0 || 2876 (error = sa6_embedscope(&addrs[1], V_ip6_use_defzone)) != 0) { 2877 return (error); 2878 } 2879 if (IN6_IS_ADDR_V4MAPPED(&addrs[0].sin6_addr)) { 2880 #ifdef INET 2881 if (IN6_IS_ADDR_V4MAPPED(&addrs[1].sin6_addr)) 2882 mapped = 1; 2883 else 2884 #endif 2885 return (EINVAL); 2886 } 2887 2888 NET_EPOCH_ENTER(et); 2889 #ifdef INET 2890 if (mapped == 1) 2891 inp = in_pcblookup(&V_tcbinfo, 2892 *(struct in_addr *)&addrs[1].sin6_addr.s6_addr[12], 2893 addrs[1].sin6_port, 2894 *(struct in_addr *)&addrs[0].sin6_addr.s6_addr[12], 2895 addrs[0].sin6_port, INPLOOKUP_RLOCKPCB, NULL); 2896 else 2897 #endif 2898 inp = in6_pcblookup(&V_tcbinfo, 2899 &addrs[1].sin6_addr, addrs[1].sin6_port, 2900 &addrs[0].sin6_addr, addrs[0].sin6_port, 2901 INPLOOKUP_RLOCKPCB, NULL); 2902 NET_EPOCH_EXIT(et); 2903 if (inp != NULL) { 2904 if (inp->inp_socket == NULL) 2905 error = ENOENT; 2906 if (error == 0) 2907 error = cr_canseeinpcb(req->td->td_ucred, inp); 2908 if (error == 0) 2909 cru2x(inp->inp_cred, &xuc); 2910 INP_RUNLOCK(inp); 2911 } else 2912 error = ENOENT; 2913 if (error == 0) 2914 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 2915 return (error); 2916 } 2917 2918 SYSCTL_PROC(_net_inet6_tcp6, OID_AUTO, getcred, 2919 CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_NEEDGIANT, 2920 0, 0, tcp6_getcred, "S,xucred", 2921 "Get the xucred of a TCP6 connection"); 2922 #endif /* INET6 */ 2923 2924 #ifdef INET 2925 /* Path MTU to try next when a fragmentation-needed message is received. */ 2926 static inline int 2927 tcp_next_pmtu(const struct icmp *icp, const struct ip *ip) 2928 { 2929 int mtu = ntohs(icp->icmp_nextmtu); 2930 2931 /* If no alternative MTU was proposed, try the next smaller one. */ 2932 if (!mtu) 2933 mtu = ip_next_mtu(ntohs(ip->ip_len), 1); 2934 if (mtu < V_tcp_minmss + sizeof(struct tcpiphdr)) 2935 mtu = V_tcp_minmss + sizeof(struct tcpiphdr); 2936 2937 return (mtu); 2938 } 2939 2940 static void 2941 tcp_ctlinput_with_port(int cmd, struct sockaddr *sa, void *vip, uint16_t port) 2942 { 2943 struct ip *ip = vip; 2944 struct tcphdr *th; 2945 struct in_addr faddr; 2946 struct inpcb *inp; 2947 struct tcpcb *tp; 2948 struct inpcb *(*notify)(struct inpcb *, int) = tcp_notify; 2949 struct icmp *icp; 2950 struct in_conninfo inc; 2951 tcp_seq icmp_tcp_seq; 2952 int mtu; 2953 2954 faddr = ((struct sockaddr_in *)sa)->sin_addr; 2955 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY) 2956 return; 2957 2958 if (cmd == PRC_MSGSIZE) 2959 notify = tcp_mtudisc_notify; 2960 else if (V_icmp_may_rst && (cmd == PRC_UNREACH_ADMIN_PROHIB || 2961 cmd == PRC_UNREACH_PORT || cmd == PRC_UNREACH_PROTOCOL || 2962 cmd == PRC_TIMXCEED_INTRANS) && ip) 2963 notify = tcp_drop_syn_sent; 2964 2965 /* 2966 * Hostdead is ugly because it goes linearly through all PCBs. 2967 * XXX: We never get this from ICMP, otherwise it makes an 2968 * excellent DoS attack on machines with many connections. 2969 */ 2970 else if (cmd == PRC_HOSTDEAD) 2971 ip = NULL; 2972 else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0) 2973 return; 2974 2975 if (ip == NULL) { 2976 in_pcbnotifyall(&V_tcbinfo, faddr, inetctlerrmap[cmd], notify); 2977 return; 2978 } 2979 2980 icp = (struct icmp *)((caddr_t)ip - offsetof(struct icmp, icmp_ip)); 2981 th = (struct tcphdr *)((caddr_t)ip + (ip->ip_hl << 2)); 2982 inp = in_pcblookup(&V_tcbinfo, faddr, th->th_dport, ip->ip_src, 2983 th->th_sport, INPLOOKUP_WLOCKPCB, NULL); 2984 if (inp != NULL && PRC_IS_REDIRECT(cmd)) { 2985 /* signal EHOSTDOWN, as it flushes the cached route */ 2986 inp = (*notify)(inp, EHOSTDOWN); 2987 goto out; 2988 } 2989 icmp_tcp_seq = th->th_seq; 2990 if (inp != NULL) { 2991 if (!(inp->inp_flags & INP_TIMEWAIT) && 2992 !(inp->inp_flags & INP_DROPPED) && 2993 !(inp->inp_socket == NULL)) { 2994 tp = intotcpcb(inp); 2995 #ifdef TCP_OFFLOAD 2996 if (tp->t_flags & TF_TOE && cmd == PRC_MSGSIZE) { 2997 /* 2998 * MTU discovery for offloaded connections. Let 2999 * the TOE driver verify seq# and process it. 3000 */ 3001 mtu = tcp_next_pmtu(icp, ip); 3002 tcp_offload_pmtu_update(tp, icmp_tcp_seq, mtu); 3003 goto out; 3004 } 3005 #endif 3006 if (tp->t_port != port) { 3007 goto out; 3008 } 3009 if (SEQ_GEQ(ntohl(icmp_tcp_seq), tp->snd_una) && 3010 SEQ_LT(ntohl(icmp_tcp_seq), tp->snd_max)) { 3011 if (cmd == PRC_MSGSIZE) { 3012 /* 3013 * MTU discovery: we got a needfrag and 3014 * will potentially try a lower MTU. 3015 */ 3016 mtu = tcp_next_pmtu(icp, ip); 3017 3018 /* 3019 * Only process the offered MTU if it 3020 * is smaller than the current one. 3021 */ 3022 if (mtu < tp->t_maxseg + 3023 sizeof(struct tcpiphdr)) { 3024 bzero(&inc, sizeof(inc)); 3025 inc.inc_faddr = faddr; 3026 inc.inc_fibnum = 3027 inp->inp_inc.inc_fibnum; 3028 tcp_hc_updatemtu(&inc, mtu); 3029 tcp_mtudisc(inp, mtu); 3030 } 3031 } else 3032 inp = (*notify)(inp, 3033 inetctlerrmap[cmd]); 3034 } 3035 } 3036 } else { 3037 bzero(&inc, sizeof(inc)); 3038 inc.inc_fport = th->th_dport; 3039 inc.inc_lport = th->th_sport; 3040 inc.inc_faddr = faddr; 3041 inc.inc_laddr = ip->ip_src; 3042 syncache_unreach(&inc, icmp_tcp_seq, port); 3043 } 3044 out: 3045 if (inp != NULL) 3046 INP_WUNLOCK(inp); 3047 } 3048 3049 void 3050 tcp_ctlinput(int cmd, struct sockaddr *sa, void *vip) 3051 { 3052 tcp_ctlinput_with_port(cmd, sa, vip, htons(0)); 3053 } 3054 3055 void 3056 tcp_ctlinput_viaudp(int cmd, struct sockaddr *sa, void *vip, void *unused) 3057 { 3058 /* Its a tunneled TCP over UDP icmp */ 3059 struct ip *outer_ip, *inner_ip; 3060 struct icmp *icmp; 3061 struct udphdr *udp; 3062 struct tcphdr *th, ttemp; 3063 int i_hlen, o_len; 3064 uint16_t port; 3065 3066 inner_ip = (struct ip *)vip; 3067 icmp = (struct icmp *)((caddr_t)inner_ip - 3068 (sizeof(struct icmp) - sizeof(struct ip))); 3069 outer_ip = (struct ip *)((caddr_t)icmp - sizeof(struct ip)); 3070 i_hlen = inner_ip->ip_hl << 2; 3071 o_len = ntohs(outer_ip->ip_len); 3072 if (o_len < 3073 (sizeof(struct ip) + 8 + i_hlen + sizeof(struct udphdr) + offsetof(struct tcphdr, th_ack))) { 3074 /* Not enough data present */ 3075 return; 3076 } 3077 /* Ok lets strip out the inner udphdr header by copying up on top of it the tcp hdr */ 3078 udp = (struct udphdr *)(((caddr_t)inner_ip) + i_hlen); 3079 if (ntohs(udp->uh_sport) != V_tcp_udp_tunneling_port) { 3080 return; 3081 } 3082 port = udp->uh_dport; 3083 th = (struct tcphdr *)(udp + 1); 3084 memcpy(&ttemp, th, sizeof(struct tcphdr)); 3085 memcpy(udp, &ttemp, sizeof(struct tcphdr)); 3086 /* Now adjust down the size of the outer IP header */ 3087 o_len -= sizeof(struct udphdr); 3088 outer_ip->ip_len = htons(o_len); 3089 /* Now call in to the normal handling code */ 3090 tcp_ctlinput_with_port(cmd, sa, vip, port); 3091 } 3092 #endif /* INET */ 3093 3094 #ifdef INET6 3095 static inline int 3096 tcp6_next_pmtu(const struct icmp6_hdr *icmp6) 3097 { 3098 int mtu = ntohl(icmp6->icmp6_mtu); 3099 3100 /* 3101 * If no alternative MTU was proposed, or the proposed MTU was too 3102 * small, set to the min. 3103 */ 3104 if (mtu < IPV6_MMTU) 3105 mtu = IPV6_MMTU - 8; /* XXXNP: what is the adjustment for? */ 3106 return (mtu); 3107 } 3108 3109 static void 3110 tcp6_ctlinput_with_port(int cmd, struct sockaddr *sa, void *d, uint16_t port) 3111 { 3112 struct in6_addr *dst; 3113 struct inpcb *(*notify)(struct inpcb *, int) = tcp_notify; 3114 struct ip6_hdr *ip6; 3115 struct mbuf *m; 3116 struct inpcb *inp; 3117 struct tcpcb *tp; 3118 struct icmp6_hdr *icmp6; 3119 struct ip6ctlparam *ip6cp = NULL; 3120 const struct sockaddr_in6 *sa6_src = NULL; 3121 struct in_conninfo inc; 3122 struct tcp_ports { 3123 uint16_t th_sport; 3124 uint16_t th_dport; 3125 } t_ports; 3126 tcp_seq icmp_tcp_seq; 3127 unsigned int mtu; 3128 unsigned int off; 3129 3130 if (sa->sa_family != AF_INET6 || 3131 sa->sa_len != sizeof(struct sockaddr_in6)) 3132 return; 3133 3134 /* if the parameter is from icmp6, decode it. */ 3135 if (d != NULL) { 3136 ip6cp = (struct ip6ctlparam *)d; 3137 icmp6 = ip6cp->ip6c_icmp6; 3138 m = ip6cp->ip6c_m; 3139 ip6 = ip6cp->ip6c_ip6; 3140 off = ip6cp->ip6c_off; 3141 sa6_src = ip6cp->ip6c_src; 3142 dst = ip6cp->ip6c_finaldst; 3143 } else { 3144 m = NULL; 3145 ip6 = NULL; 3146 off = 0; /* fool gcc */ 3147 sa6_src = &sa6_any; 3148 dst = NULL; 3149 } 3150 3151 if (cmd == PRC_MSGSIZE) 3152 notify = tcp_mtudisc_notify; 3153 else if (V_icmp_may_rst && (cmd == PRC_UNREACH_ADMIN_PROHIB || 3154 cmd == PRC_UNREACH_PORT || cmd == PRC_UNREACH_PROTOCOL || 3155 cmd == PRC_TIMXCEED_INTRANS) && ip6 != NULL) 3156 notify = tcp_drop_syn_sent; 3157 3158 /* 3159 * Hostdead is ugly because it goes linearly through all PCBs. 3160 * XXX: We never get this from ICMP, otherwise it makes an 3161 * excellent DoS attack on machines with many connections. 3162 */ 3163 else if (cmd == PRC_HOSTDEAD) 3164 ip6 = NULL; 3165 else if ((unsigned)cmd >= PRC_NCMDS || inet6ctlerrmap[cmd] == 0) 3166 return; 3167 3168 if (ip6 == NULL) { 3169 in6_pcbnotify(&V_tcbinfo, sa, 0, 3170 (const struct sockaddr *)sa6_src, 3171 0, cmd, NULL, notify); 3172 return; 3173 } 3174 3175 /* Check if we can safely get the ports from the tcp hdr */ 3176 if (m == NULL || 3177 (m->m_pkthdr.len < 3178 (int32_t) (off + sizeof(struct tcp_ports)))) { 3179 return; 3180 } 3181 bzero(&t_ports, sizeof(struct tcp_ports)); 3182 m_copydata(m, off, sizeof(struct tcp_ports), (caddr_t)&t_ports); 3183 inp = in6_pcblookup(&V_tcbinfo, &ip6->ip6_dst, t_ports.th_dport, 3184 &ip6->ip6_src, t_ports.th_sport, INPLOOKUP_WLOCKPCB, NULL); 3185 if (inp != NULL && PRC_IS_REDIRECT(cmd)) { 3186 /* signal EHOSTDOWN, as it flushes the cached route */ 3187 inp = (*notify)(inp, EHOSTDOWN); 3188 goto out; 3189 } 3190 off += sizeof(struct tcp_ports); 3191 if (m->m_pkthdr.len < (int32_t) (off + sizeof(tcp_seq))) { 3192 goto out; 3193 } 3194 m_copydata(m, off, sizeof(tcp_seq), (caddr_t)&icmp_tcp_seq); 3195 if (inp != NULL) { 3196 if (!(inp->inp_flags & INP_TIMEWAIT) && 3197 !(inp->inp_flags & INP_DROPPED) && 3198 !(inp->inp_socket == NULL)) { 3199 tp = intotcpcb(inp); 3200 #ifdef TCP_OFFLOAD 3201 if (tp->t_flags & TF_TOE && cmd == PRC_MSGSIZE) { 3202 /* MTU discovery for offloaded connections. */ 3203 mtu = tcp6_next_pmtu(icmp6); 3204 tcp_offload_pmtu_update(tp, icmp_tcp_seq, mtu); 3205 goto out; 3206 } 3207 #endif 3208 if (tp->t_port != port) { 3209 goto out; 3210 } 3211 if (SEQ_GEQ(ntohl(icmp_tcp_seq), tp->snd_una) && 3212 SEQ_LT(ntohl(icmp_tcp_seq), tp->snd_max)) { 3213 if (cmd == PRC_MSGSIZE) { 3214 /* 3215 * MTU discovery: 3216 * If we got a needfrag set the MTU 3217 * in the route to the suggested new 3218 * value (if given) and then notify. 3219 */ 3220 mtu = tcp6_next_pmtu(icmp6); 3221 3222 bzero(&inc, sizeof(inc)); 3223 inc.inc_fibnum = M_GETFIB(m); 3224 inc.inc_flags |= INC_ISIPV6; 3225 inc.inc6_faddr = *dst; 3226 if (in6_setscope(&inc.inc6_faddr, 3227 m->m_pkthdr.rcvif, NULL)) 3228 goto out; 3229 /* 3230 * Only process the offered MTU if it 3231 * is smaller than the current one. 3232 */ 3233 if (mtu < tp->t_maxseg + 3234 sizeof (struct tcphdr) + 3235 sizeof (struct ip6_hdr)) { 3236 tcp_hc_updatemtu(&inc, mtu); 3237 tcp_mtudisc(inp, mtu); 3238 ICMP6STAT_INC(icp6s_pmtuchg); 3239 } 3240 } else 3241 inp = (*notify)(inp, 3242 inet6ctlerrmap[cmd]); 3243 } 3244 } 3245 } else { 3246 bzero(&inc, sizeof(inc)); 3247 inc.inc_fibnum = M_GETFIB(m); 3248 inc.inc_flags |= INC_ISIPV6; 3249 inc.inc_fport = t_ports.th_dport; 3250 inc.inc_lport = t_ports.th_sport; 3251 inc.inc6_faddr = *dst; 3252 inc.inc6_laddr = ip6->ip6_src; 3253 syncache_unreach(&inc, icmp_tcp_seq, port); 3254 } 3255 out: 3256 if (inp != NULL) 3257 INP_WUNLOCK(inp); 3258 } 3259 3260 void 3261 tcp6_ctlinput(int cmd, struct sockaddr *sa, void *d) 3262 { 3263 tcp6_ctlinput_with_port(cmd, sa, d, htons(0)); 3264 } 3265 3266 void 3267 tcp6_ctlinput_viaudp(int cmd, struct sockaddr *sa, void *d, void *unused) 3268 { 3269 struct ip6ctlparam *ip6cp; 3270 struct mbuf *m; 3271 struct udphdr *udp; 3272 uint16_t port; 3273 3274 ip6cp = (struct ip6ctlparam *)d; 3275 m = m_pulldown(ip6cp->ip6c_m, ip6cp->ip6c_off, sizeof(struct udphdr), NULL); 3276 if (m == NULL) { 3277 return; 3278 } 3279 udp = mtod(m, struct udphdr *); 3280 if (ntohs(udp->uh_sport) != V_tcp_udp_tunneling_port) { 3281 return; 3282 } 3283 port = udp->uh_dport; 3284 m_adj(m, sizeof(struct udphdr)); 3285 if ((m->m_flags & M_PKTHDR) == 0) { 3286 ip6cp->ip6c_m->m_pkthdr.len -= sizeof(struct udphdr); 3287 } 3288 /* Now call in to the normal handling code */ 3289 tcp6_ctlinput_with_port(cmd, sa, d, port); 3290 } 3291 3292 #endif /* INET6 */ 3293 3294 static uint32_t 3295 tcp_keyed_hash(struct in_conninfo *inc, u_char *key, u_int len) 3296 { 3297 SIPHASH_CTX ctx; 3298 uint32_t hash[2]; 3299 3300 KASSERT(len >= SIPHASH_KEY_LENGTH, 3301 ("%s: keylen %u too short ", __func__, len)); 3302 SipHash24_Init(&ctx); 3303 SipHash_SetKey(&ctx, (uint8_t *)key); 3304 SipHash_Update(&ctx, &inc->inc_fport, sizeof(uint16_t)); 3305 SipHash_Update(&ctx, &inc->inc_lport, sizeof(uint16_t)); 3306 switch (inc->inc_flags & INC_ISIPV6) { 3307 #ifdef INET 3308 case 0: 3309 SipHash_Update(&ctx, &inc->inc_faddr, sizeof(struct in_addr)); 3310 SipHash_Update(&ctx, &inc->inc_laddr, sizeof(struct in_addr)); 3311 break; 3312 #endif 3313 #ifdef INET6 3314 case INC_ISIPV6: 3315 SipHash_Update(&ctx, &inc->inc6_faddr, sizeof(struct in6_addr)); 3316 SipHash_Update(&ctx, &inc->inc6_laddr, sizeof(struct in6_addr)); 3317 break; 3318 #endif 3319 } 3320 SipHash_Final((uint8_t *)hash, &ctx); 3321 3322 return (hash[0] ^ hash[1]); 3323 } 3324 3325 uint32_t 3326 tcp_new_ts_offset(struct in_conninfo *inc) 3327 { 3328 struct in_conninfo inc_store, *local_inc; 3329 3330 if (!V_tcp_ts_offset_per_conn) { 3331 memcpy(&inc_store, inc, sizeof(struct in_conninfo)); 3332 inc_store.inc_lport = 0; 3333 inc_store.inc_fport = 0; 3334 local_inc = &inc_store; 3335 } else { 3336 local_inc = inc; 3337 } 3338 return (tcp_keyed_hash(local_inc, V_ts_offset_secret, 3339 sizeof(V_ts_offset_secret))); 3340 } 3341 3342 /* 3343 * Following is where TCP initial sequence number generation occurs. 3344 * 3345 * There are two places where we must use initial sequence numbers: 3346 * 1. In SYN-ACK packets. 3347 * 2. In SYN packets. 3348 * 3349 * All ISNs for SYN-ACK packets are generated by the syncache. See 3350 * tcp_syncache.c for details. 3351 * 3352 * The ISNs in SYN packets must be monotonic; TIME_WAIT recycling 3353 * depends on this property. In addition, these ISNs should be 3354 * unguessable so as to prevent connection hijacking. To satisfy 3355 * the requirements of this situation, the algorithm outlined in 3356 * RFC 1948 is used, with only small modifications. 3357 * 3358 * Implementation details: 3359 * 3360 * Time is based off the system timer, and is corrected so that it 3361 * increases by one megabyte per second. This allows for proper 3362 * recycling on high speed LANs while still leaving over an hour 3363 * before rollover. 3364 * 3365 * As reading the *exact* system time is too expensive to be done 3366 * whenever setting up a TCP connection, we increment the time 3367 * offset in two ways. First, a small random positive increment 3368 * is added to isn_offset for each connection that is set up. 3369 * Second, the function tcp_isn_tick fires once per clock tick 3370 * and increments isn_offset as necessary so that sequence numbers 3371 * are incremented at approximately ISN_BYTES_PER_SECOND. The 3372 * random positive increments serve only to ensure that the same 3373 * exact sequence number is never sent out twice (as could otherwise 3374 * happen when a port is recycled in less than the system tick 3375 * interval.) 3376 * 3377 * net.inet.tcp.isn_reseed_interval controls the number of seconds 3378 * between seeding of isn_secret. This is normally set to zero, 3379 * as reseeding should not be necessary. 3380 * 3381 * Locking of the global variables isn_secret, isn_last_reseed, isn_offset, 3382 * isn_offset_old, and isn_ctx is performed using the ISN lock. In 3383 * general, this means holding an exclusive (write) lock. 3384 */ 3385 3386 #define ISN_BYTES_PER_SECOND 1048576 3387 #define ISN_STATIC_INCREMENT 4096 3388 #define ISN_RANDOM_INCREMENT (4096 - 1) 3389 #define ISN_SECRET_LENGTH SIPHASH_KEY_LENGTH 3390 3391 VNET_DEFINE_STATIC(u_char, isn_secret[ISN_SECRET_LENGTH]); 3392 VNET_DEFINE_STATIC(int, isn_last); 3393 VNET_DEFINE_STATIC(int, isn_last_reseed); 3394 VNET_DEFINE_STATIC(u_int32_t, isn_offset); 3395 VNET_DEFINE_STATIC(u_int32_t, isn_offset_old); 3396 3397 #define V_isn_secret VNET(isn_secret) 3398 #define V_isn_last VNET(isn_last) 3399 #define V_isn_last_reseed VNET(isn_last_reseed) 3400 #define V_isn_offset VNET(isn_offset) 3401 #define V_isn_offset_old VNET(isn_offset_old) 3402 3403 tcp_seq 3404 tcp_new_isn(struct in_conninfo *inc) 3405 { 3406 tcp_seq new_isn; 3407 u_int32_t projected_offset; 3408 3409 ISN_LOCK(); 3410 /* Seed if this is the first use, reseed if requested. */ 3411 if ((V_isn_last_reseed == 0) || ((V_tcp_isn_reseed_interval > 0) && 3412 (((u_int)V_isn_last_reseed + (u_int)V_tcp_isn_reseed_interval*hz) 3413 < (u_int)ticks))) { 3414 arc4rand(&V_isn_secret, sizeof(V_isn_secret), 0); 3415 V_isn_last_reseed = ticks; 3416 } 3417 3418 /* Compute the hash and return the ISN. */ 3419 new_isn = (tcp_seq)tcp_keyed_hash(inc, V_isn_secret, 3420 sizeof(V_isn_secret)); 3421 V_isn_offset += ISN_STATIC_INCREMENT + 3422 (arc4random() & ISN_RANDOM_INCREMENT); 3423 if (ticks != V_isn_last) { 3424 projected_offset = V_isn_offset_old + 3425 ISN_BYTES_PER_SECOND / hz * (ticks - V_isn_last); 3426 if (SEQ_GT(projected_offset, V_isn_offset)) 3427 V_isn_offset = projected_offset; 3428 V_isn_offset_old = V_isn_offset; 3429 V_isn_last = ticks; 3430 } 3431 new_isn += V_isn_offset; 3432 ISN_UNLOCK(); 3433 return (new_isn); 3434 } 3435 3436 /* 3437 * When a specific ICMP unreachable message is received and the 3438 * connection state is SYN-SENT, drop the connection. This behavior 3439 * is controlled by the icmp_may_rst sysctl. 3440 */ 3441 struct inpcb * 3442 tcp_drop_syn_sent(struct inpcb *inp, int errno) 3443 { 3444 struct tcpcb *tp; 3445 3446 NET_EPOCH_ASSERT(); 3447 INP_WLOCK_ASSERT(inp); 3448 3449 if ((inp->inp_flags & INP_TIMEWAIT) || 3450 (inp->inp_flags & INP_DROPPED)) 3451 return (inp); 3452 3453 tp = intotcpcb(inp); 3454 if (tp->t_state != TCPS_SYN_SENT) 3455 return (inp); 3456 3457 if (IS_FASTOPEN(tp->t_flags)) 3458 tcp_fastopen_disable_path(tp); 3459 3460 tp = tcp_drop(tp, errno); 3461 if (tp != NULL) 3462 return (inp); 3463 else 3464 return (NULL); 3465 } 3466 3467 /* 3468 * When `need fragmentation' ICMP is received, update our idea of the MSS 3469 * based on the new value. Also nudge TCP to send something, since we 3470 * know the packet we just sent was dropped. 3471 * This duplicates some code in the tcp_mss() function in tcp_input.c. 3472 */ 3473 static struct inpcb * 3474 tcp_mtudisc_notify(struct inpcb *inp, int error) 3475 { 3476 3477 tcp_mtudisc(inp, -1); 3478 return (inp); 3479 } 3480 3481 static void 3482 tcp_mtudisc(struct inpcb *inp, int mtuoffer) 3483 { 3484 struct tcpcb *tp; 3485 struct socket *so; 3486 3487 INP_WLOCK_ASSERT(inp); 3488 if ((inp->inp_flags & INP_TIMEWAIT) || 3489 (inp->inp_flags & INP_DROPPED)) 3490 return; 3491 3492 tp = intotcpcb(inp); 3493 KASSERT(tp != NULL, ("tcp_mtudisc: tp == NULL")); 3494 3495 tcp_mss_update(tp, -1, mtuoffer, NULL, NULL); 3496 3497 so = inp->inp_socket; 3498 SOCKBUF_LOCK(&so->so_snd); 3499 /* If the mss is larger than the socket buffer, decrease the mss. */ 3500 if (so->so_snd.sb_hiwat < tp->t_maxseg) 3501 tp->t_maxseg = so->so_snd.sb_hiwat; 3502 SOCKBUF_UNLOCK(&so->so_snd); 3503 3504 TCPSTAT_INC(tcps_mturesent); 3505 tp->t_rtttime = 0; 3506 tp->snd_nxt = tp->snd_una; 3507 tcp_free_sackholes(tp); 3508 tp->snd_recover = tp->snd_max; 3509 if (tp->t_flags & TF_SACK_PERMIT) 3510 EXIT_FASTRECOVERY(tp->t_flags); 3511 if (tp->t_fb->tfb_tcp_mtu_chg != NULL) { 3512 /* 3513 * Conceptually the snd_nxt setting 3514 * and freeing sack holes should 3515 * be done by the default stacks 3516 * own tfb_tcp_mtu_chg(). 3517 */ 3518 tp->t_fb->tfb_tcp_mtu_chg(tp); 3519 } 3520 tp->t_fb->tfb_tcp_output(tp); 3521 } 3522 3523 #ifdef INET 3524 /* 3525 * Look-up the routing entry to the peer of this inpcb. If no route 3526 * is found and it cannot be allocated, then return 0. This routine 3527 * is called by TCP routines that access the rmx structure and by 3528 * tcp_mss_update to get the peer/interface MTU. 3529 */ 3530 uint32_t 3531 tcp_maxmtu(struct in_conninfo *inc, struct tcp_ifcap *cap) 3532 { 3533 struct nhop_object *nh; 3534 struct ifnet *ifp; 3535 uint32_t maxmtu = 0; 3536 3537 KASSERT(inc != NULL, ("tcp_maxmtu with NULL in_conninfo pointer")); 3538 3539 if (inc->inc_faddr.s_addr != INADDR_ANY) { 3540 nh = fib4_lookup(inc->inc_fibnum, inc->inc_faddr, 0, NHR_NONE, 0); 3541 if (nh == NULL) 3542 return (0); 3543 3544 ifp = nh->nh_ifp; 3545 maxmtu = nh->nh_mtu; 3546 3547 /* Report additional interface capabilities. */ 3548 if (cap != NULL) { 3549 if (ifp->if_capenable & IFCAP_TSO4 && 3550 ifp->if_hwassist & CSUM_TSO) { 3551 cap->ifcap |= CSUM_TSO; 3552 cap->tsomax = ifp->if_hw_tsomax; 3553 cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount; 3554 cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize; 3555 } 3556 } 3557 } 3558 return (maxmtu); 3559 } 3560 #endif /* INET */ 3561 3562 #ifdef INET6 3563 uint32_t 3564 tcp_maxmtu6(struct in_conninfo *inc, struct tcp_ifcap *cap) 3565 { 3566 struct nhop_object *nh; 3567 struct in6_addr dst6; 3568 uint32_t scopeid; 3569 struct ifnet *ifp; 3570 uint32_t maxmtu = 0; 3571 3572 KASSERT(inc != NULL, ("tcp_maxmtu6 with NULL in_conninfo pointer")); 3573 3574 if (inc->inc_flags & INC_IPV6MINMTU) 3575 return (IPV6_MMTU); 3576 3577 if (!IN6_IS_ADDR_UNSPECIFIED(&inc->inc6_faddr)) { 3578 in6_splitscope(&inc->inc6_faddr, &dst6, &scopeid); 3579 nh = fib6_lookup(inc->inc_fibnum, &dst6, scopeid, NHR_NONE, 0); 3580 if (nh == NULL) 3581 return (0); 3582 3583 ifp = nh->nh_ifp; 3584 maxmtu = nh->nh_mtu; 3585 3586 /* Report additional interface capabilities. */ 3587 if (cap != NULL) { 3588 if (ifp->if_capenable & IFCAP_TSO6 && 3589 ifp->if_hwassist & CSUM_TSO) { 3590 cap->ifcap |= CSUM_TSO; 3591 cap->tsomax = ifp->if_hw_tsomax; 3592 cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount; 3593 cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize; 3594 } 3595 } 3596 } 3597 3598 return (maxmtu); 3599 } 3600 3601 /* 3602 * Handle setsockopt(IPV6_USE_MIN_MTU) by a TCP stack. 3603 * 3604 * XXXGL: we are updating inpcb here with INC_IPV6MINMTU flag. 3605 * The right place to do that is ip6_setpktopt() that has just been 3606 * executed. By the way it just filled ip6po_minmtu for us. 3607 */ 3608 void 3609 tcp6_use_min_mtu(struct tcpcb *tp) 3610 { 3611 struct inpcb *inp = tp->t_inpcb; 3612 3613 INP_WLOCK_ASSERT(inp); 3614 /* 3615 * In case of the IPV6_USE_MIN_MTU socket 3616 * option, the INC_IPV6MINMTU flag to announce 3617 * a corresponding MSS during the initial 3618 * handshake. If the TCP connection is not in 3619 * the front states, just reduce the MSS being 3620 * used. This avoids the sending of TCP 3621 * segments which will be fragmented at the 3622 * IPv6 layer. 3623 */ 3624 inp->inp_inc.inc_flags |= INC_IPV6MINMTU; 3625 if ((tp->t_state >= TCPS_SYN_SENT) && 3626 (inp->inp_inc.inc_flags & INC_ISIPV6)) { 3627 struct ip6_pktopts *opt; 3628 3629 opt = inp->in6p_outputopts; 3630 if (opt != NULL && opt->ip6po_minmtu == IP6PO_MINMTU_ALL && 3631 tp->t_maxseg > TCP6_MSS) 3632 tp->t_maxseg = TCP6_MSS; 3633 } 3634 } 3635 #endif /* INET6 */ 3636 3637 /* 3638 * Calculate effective SMSS per RFC5681 definition for a given TCP 3639 * connection at its current state, taking into account SACK and etc. 3640 */ 3641 u_int 3642 tcp_maxseg(const struct tcpcb *tp) 3643 { 3644 u_int optlen; 3645 3646 if (tp->t_flags & TF_NOOPT) 3647 return (tp->t_maxseg); 3648 3649 /* 3650 * Here we have a simplified code from tcp_addoptions(), 3651 * without a proper loop, and having most of paddings hardcoded. 3652 * We might make mistakes with padding here in some edge cases, 3653 * but this is harmless, since result of tcp_maxseg() is used 3654 * only in cwnd and ssthresh estimations. 3655 */ 3656 if (TCPS_HAVEESTABLISHED(tp->t_state)) { 3657 if (tp->t_flags & TF_RCVD_TSTMP) 3658 optlen = TCPOLEN_TSTAMP_APPA; 3659 else 3660 optlen = 0; 3661 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3662 if (tp->t_flags & TF_SIGNATURE) 3663 optlen += PADTCPOLEN(TCPOLEN_SIGNATURE); 3664 #endif 3665 if ((tp->t_flags & TF_SACK_PERMIT) && tp->rcv_numsacks > 0) { 3666 optlen += TCPOLEN_SACKHDR; 3667 optlen += tp->rcv_numsacks * TCPOLEN_SACK; 3668 optlen = PADTCPOLEN(optlen); 3669 } 3670 } else { 3671 if (tp->t_flags & TF_REQ_TSTMP) 3672 optlen = TCPOLEN_TSTAMP_APPA; 3673 else 3674 optlen = PADTCPOLEN(TCPOLEN_MAXSEG); 3675 if (tp->t_flags & TF_REQ_SCALE) 3676 optlen += PADTCPOLEN(TCPOLEN_WINDOW); 3677 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3678 if (tp->t_flags & TF_SIGNATURE) 3679 optlen += PADTCPOLEN(TCPOLEN_SIGNATURE); 3680 #endif 3681 if (tp->t_flags & TF_SACK_PERMIT) 3682 optlen += PADTCPOLEN(TCPOLEN_SACK_PERMITTED); 3683 } 3684 #undef PAD 3685 optlen = min(optlen, TCP_MAXOLEN); 3686 return (tp->t_maxseg - optlen); 3687 } 3688 3689 3690 u_int 3691 tcp_fixed_maxseg(const struct tcpcb *tp) 3692 { 3693 int optlen; 3694 3695 if (tp->t_flags & TF_NOOPT) 3696 return (tp->t_maxseg); 3697 3698 /* 3699 * Here we have a simplified code from tcp_addoptions(), 3700 * without a proper loop, and having most of paddings hardcoded. 3701 * We only consider fixed options that we would send every 3702 * time I.e. SACK is not considered. This is important 3703 * for cc modules to figure out what the modulo of the 3704 * cwnd should be. 3705 */ 3706 #define PAD(len) ((((len) / 4) + !!((len) % 4)) * 4) 3707 if (TCPS_HAVEESTABLISHED(tp->t_state)) { 3708 if (tp->t_flags & TF_RCVD_TSTMP) 3709 optlen = TCPOLEN_TSTAMP_APPA; 3710 else 3711 optlen = 0; 3712 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3713 if (tp->t_flags & TF_SIGNATURE) 3714 optlen += PAD(TCPOLEN_SIGNATURE); 3715 #endif 3716 } else { 3717 if (tp->t_flags & TF_REQ_TSTMP) 3718 optlen = TCPOLEN_TSTAMP_APPA; 3719 else 3720 optlen = PAD(TCPOLEN_MAXSEG); 3721 if (tp->t_flags & TF_REQ_SCALE) 3722 optlen += PAD(TCPOLEN_WINDOW); 3723 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3724 if (tp->t_flags & TF_SIGNATURE) 3725 optlen += PAD(TCPOLEN_SIGNATURE); 3726 #endif 3727 if (tp->t_flags & TF_SACK_PERMIT) 3728 optlen += PAD(TCPOLEN_SACK_PERMITTED); 3729 } 3730 #undef PAD 3731 optlen = min(optlen, TCP_MAXOLEN); 3732 return (tp->t_maxseg - optlen); 3733 } 3734 3735 3736 3737 static int 3738 sysctl_drop(SYSCTL_HANDLER_ARGS) 3739 { 3740 /* addrs[0] is a foreign socket, addrs[1] is a local one. */ 3741 struct sockaddr_storage addrs[2]; 3742 struct inpcb *inp; 3743 struct tcpcb *tp; 3744 struct tcptw *tw; 3745 struct sockaddr_in *fin, *lin; 3746 struct epoch_tracker et; 3747 #ifdef INET6 3748 struct sockaddr_in6 *fin6, *lin6; 3749 #endif 3750 int error; 3751 3752 inp = NULL; 3753 fin = lin = NULL; 3754 #ifdef INET6 3755 fin6 = lin6 = NULL; 3756 #endif 3757 error = 0; 3758 3759 if (req->oldptr != NULL || req->oldlen != 0) 3760 return (EINVAL); 3761 if (req->newptr == NULL) 3762 return (EPERM); 3763 if (req->newlen < sizeof(addrs)) 3764 return (ENOMEM); 3765 error = SYSCTL_IN(req, &addrs, sizeof(addrs)); 3766 if (error) 3767 return (error); 3768 3769 switch (addrs[0].ss_family) { 3770 #ifdef INET6 3771 case AF_INET6: 3772 fin6 = (struct sockaddr_in6 *)&addrs[0]; 3773 lin6 = (struct sockaddr_in6 *)&addrs[1]; 3774 if (fin6->sin6_len != sizeof(struct sockaddr_in6) || 3775 lin6->sin6_len != sizeof(struct sockaddr_in6)) 3776 return (EINVAL); 3777 if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr)) { 3778 if (!IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr)) 3779 return (EINVAL); 3780 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[0]); 3781 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[1]); 3782 fin = (struct sockaddr_in *)&addrs[0]; 3783 lin = (struct sockaddr_in *)&addrs[1]; 3784 break; 3785 } 3786 error = sa6_embedscope(fin6, V_ip6_use_defzone); 3787 if (error) 3788 return (error); 3789 error = sa6_embedscope(lin6, V_ip6_use_defzone); 3790 if (error) 3791 return (error); 3792 break; 3793 #endif 3794 #ifdef INET 3795 case AF_INET: 3796 fin = (struct sockaddr_in *)&addrs[0]; 3797 lin = (struct sockaddr_in *)&addrs[1]; 3798 if (fin->sin_len != sizeof(struct sockaddr_in) || 3799 lin->sin_len != sizeof(struct sockaddr_in)) 3800 return (EINVAL); 3801 break; 3802 #endif 3803 default: 3804 return (EINVAL); 3805 } 3806 NET_EPOCH_ENTER(et); 3807 switch (addrs[0].ss_family) { 3808 #ifdef INET6 3809 case AF_INET6: 3810 inp = in6_pcblookup(&V_tcbinfo, &fin6->sin6_addr, 3811 fin6->sin6_port, &lin6->sin6_addr, lin6->sin6_port, 3812 INPLOOKUP_WLOCKPCB, NULL); 3813 break; 3814 #endif 3815 #ifdef INET 3816 case AF_INET: 3817 inp = in_pcblookup(&V_tcbinfo, fin->sin_addr, fin->sin_port, 3818 lin->sin_addr, lin->sin_port, INPLOOKUP_WLOCKPCB, NULL); 3819 break; 3820 #endif 3821 } 3822 if (inp != NULL) { 3823 if (inp->inp_flags & INP_TIMEWAIT) { 3824 /* 3825 * XXXRW: There currently exists a state where an 3826 * inpcb is present, but its timewait state has been 3827 * discarded. For now, don't allow dropping of this 3828 * type of inpcb. 3829 */ 3830 tw = intotw(inp); 3831 if (tw != NULL) 3832 tcp_twclose(tw, 0); 3833 else 3834 INP_WUNLOCK(inp); 3835 } else if ((inp->inp_flags & INP_DROPPED) == 0 && 3836 !SOLISTENING(inp->inp_socket)) { 3837 tp = intotcpcb(inp); 3838 tp = tcp_drop(tp, ECONNABORTED); 3839 if (tp != NULL) 3840 INP_WUNLOCK(inp); 3841 } else 3842 INP_WUNLOCK(inp); 3843 } else 3844 error = ESRCH; 3845 NET_EPOCH_EXIT(et); 3846 return (error); 3847 } 3848 3849 SYSCTL_PROC(_net_inet_tcp, TCPCTL_DROP, drop, 3850 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | 3851 CTLFLAG_NEEDGIANT, NULL, 0, sysctl_drop, "", 3852 "Drop TCP connection"); 3853 3854 #ifdef KERN_TLS 3855 static int 3856 sysctl_switch_tls(SYSCTL_HANDLER_ARGS) 3857 { 3858 /* addrs[0] is a foreign socket, addrs[1] is a local one. */ 3859 struct sockaddr_storage addrs[2]; 3860 struct inpcb *inp; 3861 struct sockaddr_in *fin, *lin; 3862 struct epoch_tracker et; 3863 #ifdef INET6 3864 struct sockaddr_in6 *fin6, *lin6; 3865 #endif 3866 int error; 3867 3868 inp = NULL; 3869 fin = lin = NULL; 3870 #ifdef INET6 3871 fin6 = lin6 = NULL; 3872 #endif 3873 error = 0; 3874 3875 if (req->oldptr != NULL || req->oldlen != 0) 3876 return (EINVAL); 3877 if (req->newptr == NULL) 3878 return (EPERM); 3879 if (req->newlen < sizeof(addrs)) 3880 return (ENOMEM); 3881 error = SYSCTL_IN(req, &addrs, sizeof(addrs)); 3882 if (error) 3883 return (error); 3884 3885 switch (addrs[0].ss_family) { 3886 #ifdef INET6 3887 case AF_INET6: 3888 fin6 = (struct sockaddr_in6 *)&addrs[0]; 3889 lin6 = (struct sockaddr_in6 *)&addrs[1]; 3890 if (fin6->sin6_len != sizeof(struct sockaddr_in6) || 3891 lin6->sin6_len != sizeof(struct sockaddr_in6)) 3892 return (EINVAL); 3893 if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr)) { 3894 if (!IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr)) 3895 return (EINVAL); 3896 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[0]); 3897 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[1]); 3898 fin = (struct sockaddr_in *)&addrs[0]; 3899 lin = (struct sockaddr_in *)&addrs[1]; 3900 break; 3901 } 3902 error = sa6_embedscope(fin6, V_ip6_use_defzone); 3903 if (error) 3904 return (error); 3905 error = sa6_embedscope(lin6, V_ip6_use_defzone); 3906 if (error) 3907 return (error); 3908 break; 3909 #endif 3910 #ifdef INET 3911 case AF_INET: 3912 fin = (struct sockaddr_in *)&addrs[0]; 3913 lin = (struct sockaddr_in *)&addrs[1]; 3914 if (fin->sin_len != sizeof(struct sockaddr_in) || 3915 lin->sin_len != sizeof(struct sockaddr_in)) 3916 return (EINVAL); 3917 break; 3918 #endif 3919 default: 3920 return (EINVAL); 3921 } 3922 NET_EPOCH_ENTER(et); 3923 switch (addrs[0].ss_family) { 3924 #ifdef INET6 3925 case AF_INET6: 3926 inp = in6_pcblookup(&V_tcbinfo, &fin6->sin6_addr, 3927 fin6->sin6_port, &lin6->sin6_addr, lin6->sin6_port, 3928 INPLOOKUP_WLOCKPCB, NULL); 3929 break; 3930 #endif 3931 #ifdef INET 3932 case AF_INET: 3933 inp = in_pcblookup(&V_tcbinfo, fin->sin_addr, fin->sin_port, 3934 lin->sin_addr, lin->sin_port, INPLOOKUP_WLOCKPCB, NULL); 3935 break; 3936 #endif 3937 } 3938 NET_EPOCH_EXIT(et); 3939 if (inp != NULL) { 3940 if ((inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) != 0 || 3941 inp->inp_socket == NULL) { 3942 error = ECONNRESET; 3943 INP_WUNLOCK(inp); 3944 } else { 3945 struct socket *so; 3946 3947 so = inp->inp_socket; 3948 soref(so); 3949 error = ktls_set_tx_mode(so, 3950 arg2 == 0 ? TCP_TLS_MODE_SW : TCP_TLS_MODE_IFNET); 3951 INP_WUNLOCK(inp); 3952 sorele(so); 3953 } 3954 } else 3955 error = ESRCH; 3956 return (error); 3957 } 3958 3959 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, switch_to_sw_tls, 3960 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | 3961 CTLFLAG_NEEDGIANT, NULL, 0, sysctl_switch_tls, "", 3962 "Switch TCP connection to SW TLS"); 3963 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, switch_to_ifnet_tls, 3964 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | 3965 CTLFLAG_NEEDGIANT, NULL, 1, sysctl_switch_tls, "", 3966 "Switch TCP connection to ifnet TLS"); 3967 #endif 3968 3969 /* 3970 * Generate a standardized TCP log line for use throughout the 3971 * tcp subsystem. Memory allocation is done with M_NOWAIT to 3972 * allow use in the interrupt context. 3973 * 3974 * NB: The caller MUST free(s, M_TCPLOG) the returned string. 3975 * NB: The function may return NULL if memory allocation failed. 3976 * 3977 * Due to header inclusion and ordering limitations the struct ip 3978 * and ip6_hdr pointers have to be passed as void pointers. 3979 */ 3980 char * 3981 tcp_log_vain(struct in_conninfo *inc, struct tcphdr *th, void *ip4hdr, 3982 const void *ip6hdr) 3983 { 3984 3985 /* Is logging enabled? */ 3986 if (V_tcp_log_in_vain == 0) 3987 return (NULL); 3988 3989 return (tcp_log_addr(inc, th, ip4hdr, ip6hdr)); 3990 } 3991 3992 char * 3993 tcp_log_addrs(struct in_conninfo *inc, struct tcphdr *th, void *ip4hdr, 3994 const void *ip6hdr) 3995 { 3996 3997 /* Is logging enabled? */ 3998 if (tcp_log_debug == 0) 3999 return (NULL); 4000 4001 return (tcp_log_addr(inc, th, ip4hdr, ip6hdr)); 4002 } 4003 4004 static char * 4005 tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th, void *ip4hdr, 4006 const void *ip6hdr) 4007 { 4008 char *s, *sp; 4009 size_t size; 4010 struct ip *ip; 4011 #ifdef INET6 4012 const struct ip6_hdr *ip6; 4013 4014 ip6 = (const struct ip6_hdr *)ip6hdr; 4015 #endif /* INET6 */ 4016 ip = (struct ip *)ip4hdr; 4017 4018 /* 4019 * The log line looks like this: 4020 * "TCP: [1.2.3.4]:50332 to [1.2.3.4]:80 tcpflags 0x2<SYN>" 4021 */ 4022 size = sizeof("TCP: []:12345 to []:12345 tcpflags 0x2<>") + 4023 sizeof(PRINT_TH_FLAGS) + 1 + 4024 #ifdef INET6 4025 2 * INET6_ADDRSTRLEN; 4026 #else 4027 2 * INET_ADDRSTRLEN; 4028 #endif /* INET6 */ 4029 4030 s = malloc(size, M_TCPLOG, M_ZERO|M_NOWAIT); 4031 if (s == NULL) 4032 return (NULL); 4033 4034 strcat(s, "TCP: ["); 4035 sp = s + strlen(s); 4036 4037 if (inc && ((inc->inc_flags & INC_ISIPV6) == 0)) { 4038 inet_ntoa_r(inc->inc_faddr, sp); 4039 sp = s + strlen(s); 4040 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport)); 4041 sp = s + strlen(s); 4042 inet_ntoa_r(inc->inc_laddr, sp); 4043 sp = s + strlen(s); 4044 sprintf(sp, "]:%i", ntohs(inc->inc_lport)); 4045 #ifdef INET6 4046 } else if (inc) { 4047 ip6_sprintf(sp, &inc->inc6_faddr); 4048 sp = s + strlen(s); 4049 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport)); 4050 sp = s + strlen(s); 4051 ip6_sprintf(sp, &inc->inc6_laddr); 4052 sp = s + strlen(s); 4053 sprintf(sp, "]:%i", ntohs(inc->inc_lport)); 4054 } else if (ip6 && th) { 4055 ip6_sprintf(sp, &ip6->ip6_src); 4056 sp = s + strlen(s); 4057 sprintf(sp, "]:%i to [", ntohs(th->th_sport)); 4058 sp = s + strlen(s); 4059 ip6_sprintf(sp, &ip6->ip6_dst); 4060 sp = s + strlen(s); 4061 sprintf(sp, "]:%i", ntohs(th->th_dport)); 4062 #endif /* INET6 */ 4063 #ifdef INET 4064 } else if (ip && th) { 4065 inet_ntoa_r(ip->ip_src, sp); 4066 sp = s + strlen(s); 4067 sprintf(sp, "]:%i to [", ntohs(th->th_sport)); 4068 sp = s + strlen(s); 4069 inet_ntoa_r(ip->ip_dst, sp); 4070 sp = s + strlen(s); 4071 sprintf(sp, "]:%i", ntohs(th->th_dport)); 4072 #endif /* INET */ 4073 } else { 4074 free(s, M_TCPLOG); 4075 return (NULL); 4076 } 4077 sp = s + strlen(s); 4078 if (th) 4079 sprintf(sp, " tcpflags 0x%b", th->th_flags, PRINT_TH_FLAGS); 4080 if (*(s + size - 1) != '\0') 4081 panic("%s: string too long", __func__); 4082 return (s); 4083 } 4084 4085 /* 4086 * A subroutine which makes it easy to track TCP state changes with DTrace. 4087 * This function shouldn't be called for t_state initializations that don't 4088 * correspond to actual TCP state transitions. 4089 */ 4090 void 4091 tcp_state_change(struct tcpcb *tp, int newstate) 4092 { 4093 #if defined(KDTRACE_HOOKS) 4094 int pstate = tp->t_state; 4095 #endif 4096 4097 TCPSTATES_DEC(tp->t_state); 4098 TCPSTATES_INC(newstate); 4099 tp->t_state = newstate; 4100 TCP_PROBE6(state__change, NULL, tp, NULL, tp, NULL, pstate); 4101 } 4102 4103 /* 4104 * Create an external-format (``xtcpcb'') structure using the information in 4105 * the kernel-format tcpcb structure pointed to by tp. This is done to 4106 * reduce the spew of irrelevant information over this interface, to isolate 4107 * user code from changes in the kernel structure, and potentially to provide 4108 * information-hiding if we decide that some of this information should be 4109 * hidden from users. 4110 */ 4111 void 4112 tcp_inptoxtp(const struct inpcb *inp, struct xtcpcb *xt) 4113 { 4114 struct tcpcb *tp = intotcpcb(inp); 4115 struct tcptw *tw = intotw(inp); 4116 sbintime_t now; 4117 4118 bzero(xt, sizeof(*xt)); 4119 if (inp->inp_flags & INP_TIMEWAIT) { 4120 xt->t_state = TCPS_TIME_WAIT; 4121 xt->xt_encaps_port = tw->t_port; 4122 } else { 4123 xt->t_state = tp->t_state; 4124 xt->t_logstate = tp->t_logstate; 4125 xt->t_flags = tp->t_flags; 4126 xt->t_sndzerowin = tp->t_sndzerowin; 4127 xt->t_sndrexmitpack = tp->t_sndrexmitpack; 4128 xt->t_rcvoopack = tp->t_rcvoopack; 4129 xt->t_rcv_wnd = tp->rcv_wnd; 4130 xt->t_snd_wnd = tp->snd_wnd; 4131 xt->t_snd_cwnd = tp->snd_cwnd; 4132 xt->t_snd_ssthresh = tp->snd_ssthresh; 4133 xt->t_dsack_bytes = tp->t_dsack_bytes; 4134 xt->t_dsack_tlp_bytes = tp->t_dsack_tlp_bytes; 4135 xt->t_dsack_pack = tp->t_dsack_pack; 4136 xt->t_maxseg = tp->t_maxseg; 4137 xt->xt_ecn = (tp->t_flags2 & TF2_ECN_PERMIT) ? 1 : 0 + 4138 (tp->t_flags2 & TF2_ACE_PERMIT) ? 2 : 0; 4139 4140 now = getsbinuptime(); 4141 #define COPYTIMER(ttt) do { \ 4142 if (callout_active(&tp->t_timers->ttt)) \ 4143 xt->ttt = (tp->t_timers->ttt.c_time - now) / \ 4144 SBT_1MS; \ 4145 else \ 4146 xt->ttt = 0; \ 4147 } while (0) 4148 COPYTIMER(tt_delack); 4149 COPYTIMER(tt_rexmt); 4150 COPYTIMER(tt_persist); 4151 COPYTIMER(tt_keep); 4152 COPYTIMER(tt_2msl); 4153 #undef COPYTIMER 4154 xt->t_rcvtime = 1000 * (ticks - tp->t_rcvtime) / hz; 4155 4156 xt->xt_encaps_port = tp->t_port; 4157 bcopy(tp->t_fb->tfb_tcp_block_name, xt->xt_stack, 4158 TCP_FUNCTION_NAME_LEN_MAX); 4159 bcopy(CC_ALGO(tp)->name, xt->xt_cc, 4160 TCP_CA_NAME_MAX); 4161 #ifdef TCP_BLACKBOX 4162 (void)tcp_log_get_id(tp, xt->xt_logid); 4163 #endif 4164 } 4165 4166 xt->xt_len = sizeof(struct xtcpcb); 4167 in_pcbtoxinpcb(inp, &xt->xt_inp); 4168 if (inp->inp_socket == NULL) 4169 xt->xt_inp.xi_socket.xso_protocol = IPPROTO_TCP; 4170 } 4171 4172 void 4173 tcp_log_end_status(struct tcpcb *tp, uint8_t status) 4174 { 4175 uint32_t bit, i; 4176 4177 if ((tp == NULL) || 4178 (status > TCP_EI_STATUS_MAX_VALUE) || 4179 (status == 0)) { 4180 /* Invalid */ 4181 return; 4182 } 4183 if (status > (sizeof(uint32_t) * 8)) { 4184 /* Should this be a KASSERT? */ 4185 return; 4186 } 4187 bit = 1U << (status - 1); 4188 if (bit & tp->t_end_info_status) { 4189 /* already logged */ 4190 return; 4191 } 4192 for (i = 0; i < TCP_END_BYTE_INFO; i++) { 4193 if (tp->t_end_info_bytes[i] == TCP_EI_EMPTY_SLOT) { 4194 tp->t_end_info_bytes[i] = status; 4195 tp->t_end_info_status |= bit; 4196 break; 4197 } 4198 } 4199 } 4200 4201 int 4202 tcp_can_enable_pacing(void) 4203 { 4204 4205 if ((tcp_pacing_limit == -1) || 4206 (tcp_pacing_limit > number_of_tcp_connections_pacing)) { 4207 atomic_fetchadd_int(&number_of_tcp_connections_pacing, 1); 4208 shadow_num_connections = number_of_tcp_connections_pacing; 4209 return (1); 4210 } else { 4211 return (0); 4212 } 4213 } 4214 4215 static uint8_t tcp_pacing_warning = 0; 4216 4217 void 4218 tcp_decrement_paced_conn(void) 4219 { 4220 uint32_t ret; 4221 4222 ret = atomic_fetchadd_int(&number_of_tcp_connections_pacing, -1); 4223 shadow_num_connections = number_of_tcp_connections_pacing; 4224 KASSERT(ret != 0, ("tcp_paced_connection_exits -1 would cause wrap?")); 4225 if (ret == 0) { 4226 if (tcp_pacing_limit != -1) { 4227 printf("Warning all pacing is now disabled, count decrements invalidly!\n"); 4228 tcp_pacing_limit = 0; 4229 } else if (tcp_pacing_warning == 0) { 4230 printf("Warning pacing count is invalid, invalid decrement\n"); 4231 tcp_pacing_warning = 1; 4232 } 4233 } 4234 } 4235