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 42 #include <sys/param.h> 43 #include <sys/systm.h> 44 #include <sys/arb.h> 45 #include <sys/callout.h> 46 #include <sys/eventhandler.h> 47 #ifdef TCP_HHOOK 48 #include <sys/hhook.h> 49 #endif 50 #include <sys/kernel.h> 51 #ifdef TCP_HHOOK 52 #include <sys/khelp.h> 53 #endif 54 #ifdef KERN_TLS 55 #include <sys/ktls.h> 56 #endif 57 #include <sys/qmath.h> 58 #include <sys/stats.h> 59 #include <sys/sysctl.h> 60 #include <sys/jail.h> 61 #include <sys/malloc.h> 62 #include <sys/refcount.h> 63 #include <sys/mbuf.h> 64 #include <sys/priv.h> 65 #include <sys/proc.h> 66 #include <sys/sdt.h> 67 #include <sys/socket.h> 68 #include <sys/socketvar.h> 69 #include <sys/protosw.h> 70 #include <sys/random.h> 71 72 #include <vm/uma.h> 73 74 #include <net/route.h> 75 #include <net/route/nhop.h> 76 #include <net/if.h> 77 #include <net/if_var.h> 78 #include <net/if_private.h> 79 #include <net/vnet.h> 80 81 #include <netinet/in.h> 82 #include <netinet/in_fib.h> 83 #include <netinet/in_kdtrace.h> 84 #include <netinet/in_pcb.h> 85 #include <netinet/in_systm.h> 86 #include <netinet/in_var.h> 87 #include <netinet/ip.h> 88 #include <netinet/ip_icmp.h> 89 #include <netinet/ip_var.h> 90 #ifdef INET6 91 #include <netinet/icmp6.h> 92 #include <netinet/ip6.h> 93 #include <netinet6/in6_fib.h> 94 #include <netinet6/in6_pcb.h> 95 #include <netinet6/ip6_var.h> 96 #include <netinet6/scope6_var.h> 97 #include <netinet6/nd6.h> 98 #endif 99 100 #include <netinet/tcp.h> 101 #ifdef INVARIANTS 102 #define TCPSTATES 103 #endif 104 #include <netinet/tcp_fsm.h> 105 #include <netinet/tcp_seq.h> 106 #include <netinet/tcp_timer.h> 107 #include <netinet/tcp_var.h> 108 #include <netinet/tcp_ecn.h> 109 #include <netinet/tcp_log_buf.h> 110 #include <netinet/tcp_syncache.h> 111 #include <netinet/tcp_hpts.h> 112 #include <netinet/tcp_lro.h> 113 #include <netinet/cc/cc.h> 114 #include <netinet/tcpip.h> 115 #include <netinet/tcp_fastopen.h> 116 #include <netinet/tcp_accounting.h> 117 #ifdef TCPPCAP 118 #include <netinet/tcp_pcap.h> 119 #endif 120 #ifdef TCP_OFFLOAD 121 #include <netinet/tcp_offload.h> 122 #endif 123 #include <netinet/udp.h> 124 #include <netinet/udp_var.h> 125 #ifdef INET6 126 #include <netinet6/tcp6_var.h> 127 #endif 128 129 #include <netipsec/ipsec_support.h> 130 131 #include <machine/in_cksum.h> 132 #include <crypto/siphash/siphash.h> 133 134 #include <security/mac/mac_framework.h> 135 136 #ifdef INET6 137 static ip6proto_ctlinput_t tcp6_ctlinput; 138 static udp_tun_icmp_t tcp6_ctlinput_viaudp; 139 #endif 140 141 VNET_DEFINE(int, tcp_mssdflt) = TCP_MSS; 142 #ifdef INET6 143 VNET_DEFINE(int, tcp_v6mssdflt) = TCP6_MSS; 144 #endif 145 146 #ifdef TCP_SAD_DETECTION 147 /* Sack attack detection thresholds and such */ 148 SYSCTL_NODE(_net_inet_tcp, OID_AUTO, sack_attack, 149 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 150 "Sack Attack detection thresholds"); 151 int32_t tcp_force_detection = 0; 152 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, force_detection, 153 CTLFLAG_RW, 154 &tcp_force_detection, 0, 155 "Do we force detection even if the INP has it off?"); 156 int32_t tcp_sad_limit = 10000; 157 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, limit, 158 CTLFLAG_RW, 159 &tcp_sad_limit, 10000, 160 "If SaD is enabled, what is the limit to sendmap entries (0 = unlimited)?"); 161 int32_t tcp_sack_to_ack_thresh = 700; /* 70 % */ 162 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, sack_to_ack_thresh, 163 CTLFLAG_RW, 164 &tcp_sack_to_ack_thresh, 700, 165 "Percentage of sacks to acks we must see above (10.1 percent is 101)?"); 166 int32_t tcp_sack_to_move_thresh = 600; /* 60 % */ 167 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, move_thresh, 168 CTLFLAG_RW, 169 &tcp_sack_to_move_thresh, 600, 170 "Percentage of sack moves we must see above (10.1 percent is 101)"); 171 int32_t tcp_restoral_thresh = 650; /* 65 % (sack:2:ack -5%) */ 172 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, restore_thresh, 173 CTLFLAG_RW, 174 &tcp_restoral_thresh, 550, 175 "Percentage of sack to ack percentage we must see below to restore(10.1 percent is 101)"); 176 int32_t tcp_sad_decay_val = 800; 177 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, decay_per, 178 CTLFLAG_RW, 179 &tcp_sad_decay_val, 800, 180 "The decay percentage (10.1 percent equals 101 )"); 181 int32_t tcp_map_minimum = 500; 182 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, nummaps, 183 CTLFLAG_RW, 184 &tcp_map_minimum, 500, 185 "Number of Map enteries before we start detection"); 186 int32_t tcp_sad_pacing_interval = 2000; 187 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, sad_pacing_int, 188 CTLFLAG_RW, 189 &tcp_sad_pacing_interval, 2000, 190 "What is the minimum pacing interval for a classified attacker?"); 191 192 int32_t tcp_sad_low_pps = 100; 193 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, sad_low_pps, 194 CTLFLAG_RW, 195 &tcp_sad_low_pps, 100, 196 "What is the input pps that below which we do not decay?"); 197 #endif 198 uint32_t tcp_ack_war_time_window = 1000; 199 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, ack_war_timewindow, 200 CTLFLAG_RW, 201 &tcp_ack_war_time_window, 1000, 202 "If the tcp_stack does ack-war prevention how many milliseconds are in its time window?"); 203 uint32_t tcp_ack_war_cnt = 5; 204 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, ack_war_cnt, 205 CTLFLAG_RW, 206 &tcp_ack_war_cnt, 5, 207 "If the tcp_stack does ack-war prevention how many acks can be sent in its time window?"); 208 209 struct rwlock tcp_function_lock; 210 211 static int 212 sysctl_net_inet_tcp_mss_check(SYSCTL_HANDLER_ARGS) 213 { 214 int error, new; 215 216 new = V_tcp_mssdflt; 217 error = sysctl_handle_int(oidp, &new, 0, req); 218 if (error == 0 && req->newptr) { 219 if (new < TCP_MINMSS) 220 error = EINVAL; 221 else 222 V_tcp_mssdflt = new; 223 } 224 return (error); 225 } 226 227 SYSCTL_PROC(_net_inet_tcp, TCPCTL_MSSDFLT, mssdflt, 228 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 229 &VNET_NAME(tcp_mssdflt), 0, &sysctl_net_inet_tcp_mss_check, "I", 230 "Default TCP Maximum Segment Size"); 231 232 #ifdef INET6 233 static int 234 sysctl_net_inet_tcp_mss_v6_check(SYSCTL_HANDLER_ARGS) 235 { 236 int error, new; 237 238 new = V_tcp_v6mssdflt; 239 error = sysctl_handle_int(oidp, &new, 0, req); 240 if (error == 0 && req->newptr) { 241 if (new < TCP_MINMSS) 242 error = EINVAL; 243 else 244 V_tcp_v6mssdflt = new; 245 } 246 return (error); 247 } 248 249 SYSCTL_PROC(_net_inet_tcp, TCPCTL_V6MSSDFLT, v6mssdflt, 250 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 251 &VNET_NAME(tcp_v6mssdflt), 0, &sysctl_net_inet_tcp_mss_v6_check, "I", 252 "Default TCP Maximum Segment Size for IPv6"); 253 #endif /* INET6 */ 254 255 /* 256 * Minimum MSS we accept and use. This prevents DoS attacks where 257 * we are forced to a ridiculous low MSS like 20 and send hundreds 258 * of packets instead of one. The effect scales with the available 259 * bandwidth and quickly saturates the CPU and network interface 260 * with packet generation and sending. Set to zero to disable MINMSS 261 * checking. This setting prevents us from sending too small packets. 262 */ 263 VNET_DEFINE(int, tcp_minmss) = TCP_MINMSS; 264 SYSCTL_INT(_net_inet_tcp, OID_AUTO, minmss, CTLFLAG_VNET | CTLFLAG_RW, 265 &VNET_NAME(tcp_minmss), 0, 266 "Minimum TCP Maximum Segment Size"); 267 268 VNET_DEFINE(int, tcp_do_rfc1323) = 1; 269 SYSCTL_INT(_net_inet_tcp, TCPCTL_DO_RFC1323, rfc1323, CTLFLAG_VNET | CTLFLAG_RW, 270 &VNET_NAME(tcp_do_rfc1323), 0, 271 "Enable rfc1323 (high performance TCP) extensions"); 272 273 /* 274 * As of June 2021, several TCP stacks violate RFC 7323 from September 2014. 275 * Some stacks negotiate TS, but never send them after connection setup. Some 276 * stacks negotiate TS, but don't send them when sending keep-alive segments. 277 * These include modern widely deployed TCP stacks. 278 * Therefore tolerating violations for now... 279 */ 280 VNET_DEFINE(int, tcp_tolerate_missing_ts) = 1; 281 SYSCTL_INT(_net_inet_tcp, OID_AUTO, tolerate_missing_ts, CTLFLAG_VNET | CTLFLAG_RW, 282 &VNET_NAME(tcp_tolerate_missing_ts), 0, 283 "Tolerate missing TCP timestamps"); 284 285 VNET_DEFINE(int, tcp_ts_offset_per_conn) = 1; 286 SYSCTL_INT(_net_inet_tcp, OID_AUTO, ts_offset_per_conn, CTLFLAG_VNET | CTLFLAG_RW, 287 &VNET_NAME(tcp_ts_offset_per_conn), 0, 288 "Initialize TCP timestamps per connection instead of per host pair"); 289 290 /* How many connections are pacing */ 291 static volatile uint32_t number_of_tcp_connections_pacing = 0; 292 static uint32_t shadow_num_connections = 0; 293 294 static int tcp_pacing_limit = 10000; 295 SYSCTL_INT(_net_inet_tcp, OID_AUTO, pacing_limit, CTLFLAG_RW, 296 &tcp_pacing_limit, 1000, 297 "If the TCP stack does pacing, is there a limit (-1 = no, 0 = no pacing N = number of connections)"); 298 299 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, pacing_count, CTLFLAG_RD, 300 &shadow_num_connections, 0, "Number of TCP connections being paced"); 301 302 static int tcp_log_debug = 0; 303 SYSCTL_INT(_net_inet_tcp, OID_AUTO, log_debug, CTLFLAG_RW, 304 &tcp_log_debug, 0, "Log errors caused by incoming TCP segments"); 305 306 static int tcp_tcbhashsize; 307 SYSCTL_INT(_net_inet_tcp, OID_AUTO, tcbhashsize, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, 308 &tcp_tcbhashsize, 0, "Size of TCP control-block hashtable"); 309 310 static int do_tcpdrain = 1; 311 SYSCTL_INT(_net_inet_tcp, OID_AUTO, do_tcpdrain, CTLFLAG_RW, &do_tcpdrain, 0, 312 "Enable tcp_drain routine for extra help when low on mbufs"); 313 314 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, pcbcount, CTLFLAG_VNET | CTLFLAG_RD, 315 &VNET_NAME(tcbinfo.ipi_count), 0, "Number of active PCBs"); 316 317 VNET_DEFINE_STATIC(int, icmp_may_rst) = 1; 318 #define V_icmp_may_rst VNET(icmp_may_rst) 319 SYSCTL_INT(_net_inet_tcp, OID_AUTO, icmp_may_rst, CTLFLAG_VNET | CTLFLAG_RW, 320 &VNET_NAME(icmp_may_rst), 0, 321 "Certain ICMP unreachable messages may abort connections in SYN_SENT"); 322 323 VNET_DEFINE_STATIC(int, tcp_isn_reseed_interval) = 0; 324 #define V_tcp_isn_reseed_interval VNET(tcp_isn_reseed_interval) 325 SYSCTL_INT(_net_inet_tcp, OID_AUTO, isn_reseed_interval, CTLFLAG_VNET | CTLFLAG_RW, 326 &VNET_NAME(tcp_isn_reseed_interval), 0, 327 "Seconds between reseeding of ISN secret"); 328 329 static int tcp_soreceive_stream; 330 SYSCTL_INT(_net_inet_tcp, OID_AUTO, soreceive_stream, CTLFLAG_RDTUN, 331 &tcp_soreceive_stream, 0, "Using soreceive_stream for TCP sockets"); 332 333 VNET_DEFINE(uma_zone_t, sack_hole_zone); 334 #define V_sack_hole_zone VNET(sack_hole_zone) 335 VNET_DEFINE(uint32_t, tcp_map_entries_limit) = 0; /* unlimited */ 336 static int 337 sysctl_net_inet_tcp_map_limit_check(SYSCTL_HANDLER_ARGS) 338 { 339 int error; 340 uint32_t new; 341 342 new = V_tcp_map_entries_limit; 343 error = sysctl_handle_int(oidp, &new, 0, req); 344 if (error == 0 && req->newptr) { 345 /* only allow "0" and value > minimum */ 346 if (new > 0 && new < TCP_MIN_MAP_ENTRIES_LIMIT) 347 error = EINVAL; 348 else 349 V_tcp_map_entries_limit = new; 350 } 351 return (error); 352 } 353 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, map_limit, 354 CTLFLAG_VNET | CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 355 &VNET_NAME(tcp_map_entries_limit), 0, 356 &sysctl_net_inet_tcp_map_limit_check, "IU", 357 "Total sendmap entries limit"); 358 359 VNET_DEFINE(uint32_t, tcp_map_split_limit) = 0; /* unlimited */ 360 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, split_limit, CTLFLAG_VNET | CTLFLAG_RW, 361 &VNET_NAME(tcp_map_split_limit), 0, 362 "Total sendmap split entries limit"); 363 364 #ifdef TCP_HHOOK 365 VNET_DEFINE(struct hhook_head *, tcp_hhh[HHOOK_TCP_LAST+1]); 366 #endif 367 368 #define TS_OFFSET_SECRET_LENGTH SIPHASH_KEY_LENGTH 369 VNET_DEFINE_STATIC(u_char, ts_offset_secret[TS_OFFSET_SECRET_LENGTH]); 370 #define V_ts_offset_secret VNET(ts_offset_secret) 371 372 static int tcp_default_fb_init(struct tcpcb *tp, void **ptr); 373 static void tcp_default_fb_fini(struct tcpcb *tp, int tcb_is_purged); 374 static int tcp_default_handoff_ok(struct tcpcb *tp); 375 static struct inpcb *tcp_notify(struct inpcb *, int); 376 static struct inpcb *tcp_mtudisc_notify(struct inpcb *, int); 377 static struct inpcb *tcp_mtudisc(struct inpcb *, int); 378 static struct inpcb *tcp_drop_syn_sent(struct inpcb *, int); 379 static char * tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th, 380 const void *ip4hdr, const void *ip6hdr); 381 static ipproto_ctlinput_t tcp_ctlinput; 382 static udp_tun_icmp_t tcp_ctlinput_viaudp; 383 384 static struct tcp_function_block tcp_def_funcblk = { 385 .tfb_tcp_block_name = "freebsd", 386 .tfb_tcp_output = tcp_default_output, 387 .tfb_tcp_do_segment = tcp_do_segment, 388 .tfb_tcp_ctloutput = tcp_default_ctloutput, 389 .tfb_tcp_handoff_ok = tcp_default_handoff_ok, 390 .tfb_tcp_fb_init = tcp_default_fb_init, 391 .tfb_tcp_fb_fini = tcp_default_fb_fini, 392 }; 393 394 static int tcp_fb_cnt = 0; 395 struct tcp_funchead t_functions; 396 VNET_DEFINE_STATIC(struct tcp_function_block *, tcp_func_set_ptr) = &tcp_def_funcblk; 397 #define V_tcp_func_set_ptr VNET(tcp_func_set_ptr) 398 399 void 400 tcp_record_dsack(struct tcpcb *tp, tcp_seq start, tcp_seq end, int tlp) 401 { 402 TCPSTAT_INC(tcps_dsack_count); 403 tp->t_dsack_pack++; 404 if (tlp == 0) { 405 if (SEQ_GT(end, start)) { 406 tp->t_dsack_bytes += (end - start); 407 TCPSTAT_ADD(tcps_dsack_bytes, (end - start)); 408 } else { 409 tp->t_dsack_tlp_bytes += (start - end); 410 TCPSTAT_ADD(tcps_dsack_bytes, (start - end)); 411 } 412 } else { 413 if (SEQ_GT(end, start)) { 414 tp->t_dsack_bytes += (end - start); 415 TCPSTAT_ADD(tcps_dsack_tlp_bytes, (end - start)); 416 } else { 417 tp->t_dsack_tlp_bytes += (start - end); 418 TCPSTAT_ADD(tcps_dsack_tlp_bytes, (start - end)); 419 } 420 } 421 } 422 423 static struct tcp_function_block * 424 find_tcp_functions_locked(struct tcp_function_set *fs) 425 { 426 struct tcp_function *f; 427 struct tcp_function_block *blk=NULL; 428 429 TAILQ_FOREACH(f, &t_functions, tf_next) { 430 if (strcmp(f->tf_name, fs->function_set_name) == 0) { 431 blk = f->tf_fb; 432 break; 433 } 434 } 435 return(blk); 436 } 437 438 static struct tcp_function_block * 439 find_tcp_fb_locked(struct tcp_function_block *blk, struct tcp_function **s) 440 { 441 struct tcp_function_block *rblk=NULL; 442 struct tcp_function *f; 443 444 TAILQ_FOREACH(f, &t_functions, tf_next) { 445 if (f->tf_fb == blk) { 446 rblk = blk; 447 if (s) { 448 *s = f; 449 } 450 break; 451 } 452 } 453 return (rblk); 454 } 455 456 struct tcp_function_block * 457 find_and_ref_tcp_functions(struct tcp_function_set *fs) 458 { 459 struct tcp_function_block *blk; 460 461 rw_rlock(&tcp_function_lock); 462 blk = find_tcp_functions_locked(fs); 463 if (blk) 464 refcount_acquire(&blk->tfb_refcnt); 465 rw_runlock(&tcp_function_lock); 466 return(blk); 467 } 468 469 struct tcp_function_block * 470 find_and_ref_tcp_fb(struct tcp_function_block *blk) 471 { 472 struct tcp_function_block *rblk; 473 474 rw_rlock(&tcp_function_lock); 475 rblk = find_tcp_fb_locked(blk, NULL); 476 if (rblk) 477 refcount_acquire(&rblk->tfb_refcnt); 478 rw_runlock(&tcp_function_lock); 479 return(rblk); 480 } 481 482 /* Find a matching alias for the given tcp_function_block. */ 483 int 484 find_tcp_function_alias(struct tcp_function_block *blk, 485 struct tcp_function_set *fs) 486 { 487 struct tcp_function *f; 488 int found; 489 490 found = 0; 491 rw_rlock(&tcp_function_lock); 492 TAILQ_FOREACH(f, &t_functions, tf_next) { 493 if ((f->tf_fb == blk) && 494 (strncmp(f->tf_name, blk->tfb_tcp_block_name, 495 TCP_FUNCTION_NAME_LEN_MAX) != 0)) { 496 /* Matching function block with different name. */ 497 strncpy(fs->function_set_name, f->tf_name, 498 TCP_FUNCTION_NAME_LEN_MAX); 499 found = 1; 500 break; 501 } 502 } 503 /* Null terminate the string appropriately. */ 504 if (found) { 505 fs->function_set_name[TCP_FUNCTION_NAME_LEN_MAX - 1] = '\0'; 506 } else { 507 fs->function_set_name[0] = '\0'; 508 } 509 rw_runlock(&tcp_function_lock); 510 return (found); 511 } 512 513 static struct tcp_function_block * 514 find_and_ref_tcp_default_fb(void) 515 { 516 struct tcp_function_block *rblk; 517 518 rw_rlock(&tcp_function_lock); 519 rblk = V_tcp_func_set_ptr; 520 refcount_acquire(&rblk->tfb_refcnt); 521 rw_runlock(&tcp_function_lock); 522 return (rblk); 523 } 524 525 void 526 tcp_switch_back_to_default(struct tcpcb *tp) 527 { 528 struct tcp_function_block *tfb; 529 void *ptr = NULL; 530 531 KASSERT(tp->t_fb != &tcp_def_funcblk, 532 ("%s: called by the built-in default stack", __func__)); 533 534 /* 535 * Now, we'll find a new function block to use. 536 * Start by trying the current user-selected 537 * default, unless this stack is the user-selected 538 * default. 539 */ 540 tfb = find_and_ref_tcp_default_fb(); 541 if (tfb == tp->t_fb) { 542 refcount_release(&tfb->tfb_refcnt); 543 tfb = NULL; 544 } 545 /* Does the stack accept this connection? */ 546 if (tfb != NULL && tfb->tfb_tcp_handoff_ok != NULL && 547 (*tfb->tfb_tcp_handoff_ok)(tp)) { 548 refcount_release(&tfb->tfb_refcnt); 549 tfb = NULL; 550 } 551 /* Try to use that stack. */ 552 if (tfb != NULL) { 553 /* Initialize the new stack. If it succeeds, we are done. */ 554 if (tfb->tfb_tcp_fb_init == NULL || 555 (*tfb->tfb_tcp_fb_init)(tp, &ptr) == 0) { 556 /* Release the old stack */ 557 if (tp->t_fb->tfb_tcp_fb_fini != NULL) 558 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 0); 559 refcount_release(&tp->t_fb->tfb_refcnt); 560 /* Now set in all the pointers */ 561 tp->t_fb = tfb; 562 tp->t_fb_ptr = ptr; 563 return; 564 } 565 /* 566 * Initialization failed. Release the reference count on 567 * the looked up default stack. 568 */ 569 refcount_release(&tfb->tfb_refcnt); 570 } 571 572 /* 573 * If that wasn't feasible, use the built-in default 574 * stack which is not allowed to reject anyone. 575 */ 576 tfb = find_and_ref_tcp_fb(&tcp_def_funcblk); 577 if (tfb == NULL) { 578 /* there always should be a default */ 579 panic("Can't refer to tcp_def_funcblk"); 580 } 581 if (tfb->tfb_tcp_handoff_ok != NULL) { 582 if ((*tfb->tfb_tcp_handoff_ok) (tp)) { 583 /* The default stack cannot say no */ 584 panic("Default stack rejects a new session?"); 585 } 586 } 587 if (tfb->tfb_tcp_fb_init != NULL && 588 (*tfb->tfb_tcp_fb_init)(tp, &ptr)) { 589 /* The default stack cannot fail */ 590 panic("Default stack initialization failed"); 591 } 592 /* Now release the old stack */ 593 if (tp->t_fb->tfb_tcp_fb_fini != NULL) 594 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 0); 595 refcount_release(&tp->t_fb->tfb_refcnt); 596 /* And set in the pointers to the new */ 597 tp->t_fb = tfb; 598 tp->t_fb_ptr = ptr; 599 } 600 601 static bool 602 tcp_recv_udp_tunneled_packet(struct mbuf *m, int off, struct inpcb *inp, 603 const struct sockaddr *sa, void *ctx) 604 { 605 struct ip *iph; 606 #ifdef INET6 607 struct ip6_hdr *ip6; 608 #endif 609 struct udphdr *uh; 610 struct tcphdr *th; 611 int thlen; 612 uint16_t port; 613 614 TCPSTAT_INC(tcps_tunneled_pkts); 615 if ((m->m_flags & M_PKTHDR) == 0) { 616 /* Can't handle one that is not a pkt hdr */ 617 TCPSTAT_INC(tcps_tunneled_errs); 618 goto out; 619 } 620 thlen = sizeof(struct tcphdr); 621 if (m->m_len < off + sizeof(struct udphdr) + thlen && 622 (m = m_pullup(m, off + sizeof(struct udphdr) + thlen)) == NULL) { 623 TCPSTAT_INC(tcps_tunneled_errs); 624 goto out; 625 } 626 iph = mtod(m, struct ip *); 627 uh = (struct udphdr *)((caddr_t)iph + off); 628 th = (struct tcphdr *)(uh + 1); 629 thlen = th->th_off << 2; 630 if (m->m_len < off + sizeof(struct udphdr) + thlen) { 631 m = m_pullup(m, off + sizeof(struct udphdr) + thlen); 632 if (m == NULL) { 633 TCPSTAT_INC(tcps_tunneled_errs); 634 goto out; 635 } else { 636 iph = mtod(m, struct ip *); 637 uh = (struct udphdr *)((caddr_t)iph + off); 638 th = (struct tcphdr *)(uh + 1); 639 } 640 } 641 m->m_pkthdr.tcp_tun_port = port = uh->uh_sport; 642 bcopy(th, uh, m->m_len - off); 643 m->m_len -= sizeof(struct udphdr); 644 m->m_pkthdr.len -= sizeof(struct udphdr); 645 /* 646 * We use the same algorithm for 647 * both UDP and TCP for c-sum. So 648 * the code in tcp_input will skip 649 * the checksum. So we do nothing 650 * with the flag (m->m_pkthdr.csum_flags). 651 */ 652 switch (iph->ip_v) { 653 #ifdef INET 654 case IPVERSION: 655 iph->ip_len = htons(ntohs(iph->ip_len) - sizeof(struct udphdr)); 656 tcp_input_with_port(&m, &off, IPPROTO_TCP, port); 657 break; 658 #endif 659 #ifdef INET6 660 case IPV6_VERSION >> 4: 661 ip6 = mtod(m, struct ip6_hdr *); 662 ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - sizeof(struct udphdr)); 663 tcp6_input_with_port(&m, &off, IPPROTO_TCP, port); 664 break; 665 #endif 666 default: 667 goto out; 668 break; 669 } 670 return (true); 671 out: 672 m_freem(m); 673 674 return (true); 675 } 676 677 static int 678 sysctl_net_inet_default_tcp_functions(SYSCTL_HANDLER_ARGS) 679 { 680 int error=ENOENT; 681 struct tcp_function_set fs; 682 struct tcp_function_block *blk; 683 684 memset(&fs, 0, sizeof(fs)); 685 rw_rlock(&tcp_function_lock); 686 blk = find_tcp_fb_locked(V_tcp_func_set_ptr, NULL); 687 if (blk) { 688 /* Found him */ 689 strcpy(fs.function_set_name, blk->tfb_tcp_block_name); 690 fs.pcbcnt = blk->tfb_refcnt; 691 } 692 rw_runlock(&tcp_function_lock); 693 error = sysctl_handle_string(oidp, fs.function_set_name, 694 sizeof(fs.function_set_name), req); 695 696 /* Check for error or no change */ 697 if (error != 0 || req->newptr == NULL) 698 return(error); 699 700 rw_wlock(&tcp_function_lock); 701 blk = find_tcp_functions_locked(&fs); 702 if ((blk == NULL) || 703 (blk->tfb_flags & TCP_FUNC_BEING_REMOVED)) { 704 error = ENOENT; 705 goto done; 706 } 707 V_tcp_func_set_ptr = blk; 708 done: 709 rw_wunlock(&tcp_function_lock); 710 return (error); 711 } 712 713 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, functions_default, 714 CTLFLAG_VNET | CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 715 NULL, 0, sysctl_net_inet_default_tcp_functions, "A", 716 "Set/get the default TCP functions"); 717 718 static int 719 sysctl_net_inet_list_available(SYSCTL_HANDLER_ARGS) 720 { 721 int error, cnt, linesz; 722 struct tcp_function *f; 723 char *buffer, *cp; 724 size_t bufsz, outsz; 725 bool alias; 726 727 cnt = 0; 728 rw_rlock(&tcp_function_lock); 729 TAILQ_FOREACH(f, &t_functions, tf_next) { 730 cnt++; 731 } 732 rw_runlock(&tcp_function_lock); 733 734 bufsz = (cnt+2) * ((TCP_FUNCTION_NAME_LEN_MAX * 2) + 13) + 1; 735 buffer = malloc(bufsz, M_TEMP, M_WAITOK); 736 737 error = 0; 738 cp = buffer; 739 740 linesz = snprintf(cp, bufsz, "\n%-32s%c %-32s %s\n", "Stack", 'D', 741 "Alias", "PCB count"); 742 cp += linesz; 743 bufsz -= linesz; 744 outsz = linesz; 745 746 rw_rlock(&tcp_function_lock); 747 TAILQ_FOREACH(f, &t_functions, tf_next) { 748 alias = (f->tf_name != f->tf_fb->tfb_tcp_block_name); 749 linesz = snprintf(cp, bufsz, "%-32s%c %-32s %u\n", 750 f->tf_fb->tfb_tcp_block_name, 751 (f->tf_fb == V_tcp_func_set_ptr) ? '*' : ' ', 752 alias ? f->tf_name : "-", 753 f->tf_fb->tfb_refcnt); 754 if (linesz >= bufsz) { 755 error = EOVERFLOW; 756 break; 757 } 758 cp += linesz; 759 bufsz -= linesz; 760 outsz += linesz; 761 } 762 rw_runlock(&tcp_function_lock); 763 if (error == 0) 764 error = sysctl_handle_string(oidp, buffer, outsz + 1, req); 765 free(buffer, M_TEMP); 766 return (error); 767 } 768 769 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, functions_available, 770 CTLFLAG_VNET | CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT, 771 NULL, 0, sysctl_net_inet_list_available, "A", 772 "list available TCP Function sets"); 773 774 VNET_DEFINE(int, tcp_udp_tunneling_port) = TCP_TUNNELING_PORT_DEFAULT; 775 776 #ifdef INET 777 VNET_DEFINE(struct socket *, udp4_tun_socket) = NULL; 778 #define V_udp4_tun_socket VNET(udp4_tun_socket) 779 #endif 780 #ifdef INET6 781 VNET_DEFINE(struct socket *, udp6_tun_socket) = NULL; 782 #define V_udp6_tun_socket VNET(udp6_tun_socket) 783 #endif 784 785 static struct sx tcpoudp_lock; 786 787 static void 788 tcp_over_udp_stop(void) 789 { 790 791 sx_assert(&tcpoudp_lock, SA_XLOCKED); 792 793 #ifdef INET 794 if (V_udp4_tun_socket != NULL) { 795 soclose(V_udp4_tun_socket); 796 V_udp4_tun_socket = NULL; 797 } 798 #endif 799 #ifdef INET6 800 if (V_udp6_tun_socket != NULL) { 801 soclose(V_udp6_tun_socket); 802 V_udp6_tun_socket = NULL; 803 } 804 #endif 805 } 806 807 static int 808 tcp_over_udp_start(void) 809 { 810 uint16_t port; 811 int ret; 812 #ifdef INET 813 struct sockaddr_in sin; 814 #endif 815 #ifdef INET6 816 struct sockaddr_in6 sin6; 817 #endif 818 819 sx_assert(&tcpoudp_lock, SA_XLOCKED); 820 821 port = V_tcp_udp_tunneling_port; 822 if (ntohs(port) == 0) { 823 /* Must have a port set */ 824 return (EINVAL); 825 } 826 #ifdef INET 827 if (V_udp4_tun_socket != NULL) { 828 /* Already running -- must stop first */ 829 return (EALREADY); 830 } 831 #endif 832 #ifdef INET6 833 if (V_udp6_tun_socket != NULL) { 834 /* Already running -- must stop first */ 835 return (EALREADY); 836 } 837 #endif 838 #ifdef INET 839 if ((ret = socreate(PF_INET, &V_udp4_tun_socket, 840 SOCK_DGRAM, IPPROTO_UDP, 841 curthread->td_ucred, curthread))) { 842 tcp_over_udp_stop(); 843 return (ret); 844 } 845 /* Call the special UDP hook. */ 846 if ((ret = udp_set_kernel_tunneling(V_udp4_tun_socket, 847 tcp_recv_udp_tunneled_packet, 848 tcp_ctlinput_viaudp, 849 NULL))) { 850 tcp_over_udp_stop(); 851 return (ret); 852 } 853 /* Ok, we have a socket, bind it to the port. */ 854 memset(&sin, 0, sizeof(struct sockaddr_in)); 855 sin.sin_len = sizeof(struct sockaddr_in); 856 sin.sin_family = AF_INET; 857 sin.sin_port = htons(port); 858 if ((ret = sobind(V_udp4_tun_socket, 859 (struct sockaddr *)&sin, curthread))) { 860 tcp_over_udp_stop(); 861 return (ret); 862 } 863 #endif 864 #ifdef INET6 865 if ((ret = socreate(PF_INET6, &V_udp6_tun_socket, 866 SOCK_DGRAM, IPPROTO_UDP, 867 curthread->td_ucred, curthread))) { 868 tcp_over_udp_stop(); 869 return (ret); 870 } 871 /* Call the special UDP hook. */ 872 if ((ret = udp_set_kernel_tunneling(V_udp6_tun_socket, 873 tcp_recv_udp_tunneled_packet, 874 tcp6_ctlinput_viaudp, 875 NULL))) { 876 tcp_over_udp_stop(); 877 return (ret); 878 } 879 /* Ok, we have a socket, bind it to the port. */ 880 memset(&sin6, 0, sizeof(struct sockaddr_in6)); 881 sin6.sin6_len = sizeof(struct sockaddr_in6); 882 sin6.sin6_family = AF_INET6; 883 sin6.sin6_port = htons(port); 884 if ((ret = sobind(V_udp6_tun_socket, 885 (struct sockaddr *)&sin6, curthread))) { 886 tcp_over_udp_stop(); 887 return (ret); 888 } 889 #endif 890 return (0); 891 } 892 893 static int 894 sysctl_net_inet_tcp_udp_tunneling_port_check(SYSCTL_HANDLER_ARGS) 895 { 896 int error; 897 uint32_t old, new; 898 899 old = V_tcp_udp_tunneling_port; 900 new = old; 901 error = sysctl_handle_int(oidp, &new, 0, req); 902 if ((error == 0) && 903 (req->newptr != NULL)) { 904 if ((new < TCP_TUNNELING_PORT_MIN) || 905 (new > TCP_TUNNELING_PORT_MAX)) { 906 error = EINVAL; 907 } else { 908 sx_xlock(&tcpoudp_lock); 909 V_tcp_udp_tunneling_port = new; 910 if (old != 0) { 911 tcp_over_udp_stop(); 912 } 913 if (new != 0) { 914 error = tcp_over_udp_start(); 915 if (error != 0) { 916 V_tcp_udp_tunneling_port = 0; 917 } 918 } 919 sx_xunlock(&tcpoudp_lock); 920 } 921 } 922 return (error); 923 } 924 925 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, udp_tunneling_port, 926 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 927 &VNET_NAME(tcp_udp_tunneling_port), 928 0, &sysctl_net_inet_tcp_udp_tunneling_port_check, "IU", 929 "Tunneling port for tcp over udp"); 930 931 VNET_DEFINE(int, tcp_udp_tunneling_overhead) = TCP_TUNNELING_OVERHEAD_DEFAULT; 932 933 static int 934 sysctl_net_inet_tcp_udp_tunneling_overhead_check(SYSCTL_HANDLER_ARGS) 935 { 936 int error, new; 937 938 new = V_tcp_udp_tunneling_overhead; 939 error = sysctl_handle_int(oidp, &new, 0, req); 940 if (error == 0 && req->newptr) { 941 if ((new < TCP_TUNNELING_OVERHEAD_MIN) || 942 (new > TCP_TUNNELING_OVERHEAD_MAX)) 943 error = EINVAL; 944 else 945 V_tcp_udp_tunneling_overhead = new; 946 } 947 return (error); 948 } 949 950 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, udp_tunneling_overhead, 951 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 952 &VNET_NAME(tcp_udp_tunneling_overhead), 953 0, &sysctl_net_inet_tcp_udp_tunneling_overhead_check, "IU", 954 "MSS reduction when using tcp over udp"); 955 956 /* 957 * Exports one (struct tcp_function_info) for each alias/name. 958 */ 959 static int 960 sysctl_net_inet_list_func_info(SYSCTL_HANDLER_ARGS) 961 { 962 int cnt, error; 963 struct tcp_function *f; 964 struct tcp_function_info tfi; 965 966 /* 967 * We don't allow writes. 968 */ 969 if (req->newptr != NULL) 970 return (EINVAL); 971 972 /* 973 * Wire the old buffer so we can directly copy the functions to 974 * user space without dropping the lock. 975 */ 976 if (req->oldptr != NULL) { 977 error = sysctl_wire_old_buffer(req, 0); 978 if (error) 979 return (error); 980 } 981 982 /* 983 * Walk the list and copy out matching entries. If INVARIANTS 984 * is compiled in, also walk the list to verify the length of 985 * the list matches what we have recorded. 986 */ 987 rw_rlock(&tcp_function_lock); 988 989 cnt = 0; 990 #ifndef INVARIANTS 991 if (req->oldptr == NULL) { 992 cnt = tcp_fb_cnt; 993 goto skip_loop; 994 } 995 #endif 996 TAILQ_FOREACH(f, &t_functions, tf_next) { 997 #ifdef INVARIANTS 998 cnt++; 999 #endif 1000 if (req->oldptr != NULL) { 1001 bzero(&tfi, sizeof(tfi)); 1002 tfi.tfi_refcnt = f->tf_fb->tfb_refcnt; 1003 tfi.tfi_id = f->tf_fb->tfb_id; 1004 (void)strlcpy(tfi.tfi_alias, f->tf_name, 1005 sizeof(tfi.tfi_alias)); 1006 (void)strlcpy(tfi.tfi_name, 1007 f->tf_fb->tfb_tcp_block_name, sizeof(tfi.tfi_name)); 1008 error = SYSCTL_OUT(req, &tfi, sizeof(tfi)); 1009 /* 1010 * Don't stop on error, as that is the 1011 * mechanism we use to accumulate length 1012 * information if the buffer was too short. 1013 */ 1014 } 1015 } 1016 KASSERT(cnt == tcp_fb_cnt, 1017 ("%s: cnt (%d) != tcp_fb_cnt (%d)", __func__, cnt, tcp_fb_cnt)); 1018 #ifndef INVARIANTS 1019 skip_loop: 1020 #endif 1021 rw_runlock(&tcp_function_lock); 1022 if (req->oldptr == NULL) 1023 error = SYSCTL_OUT(req, NULL, 1024 (cnt + 1) * sizeof(struct tcp_function_info)); 1025 1026 return (error); 1027 } 1028 1029 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, function_info, 1030 CTLTYPE_OPAQUE | CTLFLAG_SKIP | CTLFLAG_RD | CTLFLAG_MPSAFE, 1031 NULL, 0, sysctl_net_inet_list_func_info, "S,tcp_function_info", 1032 "List TCP function block name-to-ID mappings"); 1033 1034 /* 1035 * tfb_tcp_handoff_ok() function for the default stack. 1036 * Note that we'll basically try to take all comers. 1037 */ 1038 static int 1039 tcp_default_handoff_ok(struct tcpcb *tp) 1040 { 1041 1042 return (0); 1043 } 1044 1045 /* 1046 * tfb_tcp_fb_init() function for the default stack. 1047 * 1048 * This handles making sure we have appropriate timers set if you are 1049 * transitioning a socket that has some amount of setup done. 1050 * 1051 * The init() fuction from the default can *never* return non-zero i.e. 1052 * it is required to always succeed since it is the stack of last resort! 1053 */ 1054 static int 1055 tcp_default_fb_init(struct tcpcb *tp, void **ptr) 1056 { 1057 struct socket *so = tptosocket(tp); 1058 int rexmt; 1059 1060 INP_WLOCK_ASSERT(tptoinpcb(tp)); 1061 /* We don't use the pointer */ 1062 *ptr = NULL; 1063 1064 KASSERT(tp->t_state >= 0 && tp->t_state < TCPS_TIME_WAIT, 1065 ("%s: connection %p in unexpected state %d", __func__, tp, 1066 tp->t_state)); 1067 1068 /* Make sure we get no interesting mbuf queuing behavior */ 1069 /* All mbuf queue/ack compress flags should be off */ 1070 tcp_lro_features_off(tptoinpcb(tp)); 1071 1072 /* Cancel the GP measurement in progress */ 1073 tp->t_flags &= ~TF_GPUTINPROG; 1074 /* Validate the timers are not in usec, if they are convert */ 1075 tcp_change_time_units(tp, TCP_TMR_GRANULARITY_TICKS); 1076 if ((tp->t_state == TCPS_SYN_SENT) || 1077 (tp->t_state == TCPS_SYN_RECEIVED)) 1078 rexmt = tcp_rexmit_initial * tcp_backoff[tp->t_rxtshift]; 1079 else 1080 rexmt = TCP_REXMTVAL(tp) * tcp_backoff[tp->t_rxtshift]; 1081 if (tp->t_rxtshift == 0) 1082 tp->t_rxtcur = rexmt; 1083 else 1084 TCPT_RANGESET(tp->t_rxtcur, rexmt, tp->t_rttmin, TCPTV_REXMTMAX); 1085 1086 /* 1087 * Nothing to do for ESTABLISHED or LISTEN states. And, we don't 1088 * know what to do for unexpected states (which includes TIME_WAIT). 1089 */ 1090 if (tp->t_state <= TCPS_LISTEN || tp->t_state >= TCPS_TIME_WAIT) 1091 return (0); 1092 1093 /* 1094 * Make sure some kind of transmission timer is set if there is 1095 * outstanding data. 1096 */ 1097 if ((!TCPS_HAVEESTABLISHED(tp->t_state) || sbavail(&so->so_snd) || 1098 tp->snd_una != tp->snd_max) && !(tcp_timer_active(tp, TT_REXMT) || 1099 tcp_timer_active(tp, TT_PERSIST))) { 1100 /* 1101 * If the session has established and it looks like it should 1102 * be in the persist state, set the persist timer. Otherwise, 1103 * set the retransmit timer. 1104 */ 1105 if (TCPS_HAVEESTABLISHED(tp->t_state) && tp->snd_wnd == 0 && 1106 (int32_t)(tp->snd_nxt - tp->snd_una) < 1107 (int32_t)sbavail(&so->so_snd)) 1108 tcp_setpersist(tp); 1109 else 1110 tcp_timer_activate(tp, TT_REXMT, tp->t_rxtcur); 1111 } 1112 1113 /* All non-embryonic sessions get a keepalive timer. */ 1114 if (!tcp_timer_active(tp, TT_KEEP)) 1115 tcp_timer_activate(tp, TT_KEEP, 1116 TCPS_HAVEESTABLISHED(tp->t_state) ? TP_KEEPIDLE(tp) : 1117 TP_KEEPINIT(tp)); 1118 1119 /* 1120 * Make sure critical variables are initialized 1121 * if transitioning while in Recovery. 1122 */ 1123 if IN_FASTRECOVERY(tp->t_flags) { 1124 if (tp->sackhint.recover_fs == 0) 1125 tp->sackhint.recover_fs = max(1, 1126 tp->snd_nxt - tp->snd_una); 1127 } 1128 1129 return (0); 1130 } 1131 1132 /* 1133 * tfb_tcp_fb_fini() function for the default stack. 1134 * 1135 * This changes state as necessary (or prudent) to prepare for another stack 1136 * to assume responsibility for the connection. 1137 */ 1138 static void 1139 tcp_default_fb_fini(struct tcpcb *tp, int tcb_is_purged) 1140 { 1141 1142 INP_WLOCK_ASSERT(tptoinpcb(tp)); 1143 } 1144 1145 /* 1146 * Target size of TCP PCB hash tables. Must be a power of two. 1147 * 1148 * Note that this can be overridden by the kernel environment 1149 * variable net.inet.tcp.tcbhashsize 1150 */ 1151 #ifndef TCBHASHSIZE 1152 #define TCBHASHSIZE 0 1153 #endif 1154 1155 MALLOC_DEFINE(M_TCPLOG, "tcplog", "TCP address and flags print buffers"); 1156 MALLOC_DEFINE(M_TCPFUNCTIONS, "tcpfunc", "TCP function set memory"); 1157 1158 static struct mtx isn_mtx; 1159 1160 #define ISN_LOCK_INIT() mtx_init(&isn_mtx, "isn_mtx", NULL, MTX_DEF) 1161 #define ISN_LOCK() mtx_lock(&isn_mtx) 1162 #define ISN_UNLOCK() mtx_unlock(&isn_mtx) 1163 1164 INPCBSTORAGE_DEFINE(tcpcbstor, tcpcb, "tcpinp", "tcp_inpcb", "tcp", "tcphash"); 1165 1166 /* 1167 * Take a value and get the next power of 2 that doesn't overflow. 1168 * Used to size the tcp_inpcb hash buckets. 1169 */ 1170 static int 1171 maketcp_hashsize(int size) 1172 { 1173 int hashsize; 1174 1175 /* 1176 * auto tune. 1177 * get the next power of 2 higher than maxsockets. 1178 */ 1179 hashsize = 1 << fls(size); 1180 /* catch overflow, and just go one power of 2 smaller */ 1181 if (hashsize < size) { 1182 hashsize = 1 << (fls(size) - 1); 1183 } 1184 return (hashsize); 1185 } 1186 1187 static volatile int next_tcp_stack_id = 1; 1188 1189 /* 1190 * Register a TCP function block with the name provided in the names 1191 * array. (Note that this function does NOT automatically register 1192 * blk->tfb_tcp_block_name as a stack name. Therefore, you should 1193 * explicitly include blk->tfb_tcp_block_name in the list of names if 1194 * you wish to register the stack with that name.) 1195 * 1196 * Either all name registrations will succeed or all will fail. If 1197 * a name registration fails, the function will update the num_names 1198 * argument to point to the array index of the name that encountered 1199 * the failure. 1200 * 1201 * Returns 0 on success, or an error code on failure. 1202 */ 1203 int 1204 register_tcp_functions_as_names(struct tcp_function_block *blk, int wait, 1205 const char *names[], int *num_names) 1206 { 1207 struct tcp_function *n; 1208 struct tcp_function_set fs; 1209 int error, i; 1210 1211 KASSERT(names != NULL && *num_names > 0, 1212 ("%s: Called with 0-length name list", __func__)); 1213 KASSERT(names != NULL, ("%s: Called with NULL name list", __func__)); 1214 KASSERT(rw_initialized(&tcp_function_lock), 1215 ("%s: called too early", __func__)); 1216 1217 if ((blk->tfb_tcp_output == NULL) || 1218 (blk->tfb_tcp_do_segment == NULL) || 1219 (blk->tfb_tcp_ctloutput == NULL) || 1220 (strlen(blk->tfb_tcp_block_name) == 0)) { 1221 /* 1222 * These functions are required and you 1223 * need a name. 1224 */ 1225 *num_names = 0; 1226 return (EINVAL); 1227 } 1228 1229 if (blk->tfb_flags & TCP_FUNC_BEING_REMOVED) { 1230 *num_names = 0; 1231 return (EINVAL); 1232 } 1233 1234 refcount_init(&blk->tfb_refcnt, 0); 1235 blk->tfb_id = atomic_fetchadd_int(&next_tcp_stack_id, 1); 1236 for (i = 0; i < *num_names; i++) { 1237 n = malloc(sizeof(struct tcp_function), M_TCPFUNCTIONS, wait); 1238 if (n == NULL) { 1239 error = ENOMEM; 1240 goto cleanup; 1241 } 1242 n->tf_fb = blk; 1243 1244 (void)strlcpy(fs.function_set_name, names[i], 1245 sizeof(fs.function_set_name)); 1246 rw_wlock(&tcp_function_lock); 1247 if (find_tcp_functions_locked(&fs) != NULL) { 1248 /* Duplicate name space not allowed */ 1249 rw_wunlock(&tcp_function_lock); 1250 free(n, M_TCPFUNCTIONS); 1251 error = EALREADY; 1252 goto cleanup; 1253 } 1254 (void)strlcpy(n->tf_name, names[i], sizeof(n->tf_name)); 1255 TAILQ_INSERT_TAIL(&t_functions, n, tf_next); 1256 tcp_fb_cnt++; 1257 rw_wunlock(&tcp_function_lock); 1258 } 1259 return(0); 1260 1261 cleanup: 1262 /* 1263 * Deregister the names we just added. Because registration failed 1264 * for names[i], we don't need to deregister that name. 1265 */ 1266 *num_names = i; 1267 rw_wlock(&tcp_function_lock); 1268 while (--i >= 0) { 1269 TAILQ_FOREACH(n, &t_functions, tf_next) { 1270 if (!strncmp(n->tf_name, names[i], 1271 TCP_FUNCTION_NAME_LEN_MAX)) { 1272 TAILQ_REMOVE(&t_functions, n, tf_next); 1273 tcp_fb_cnt--; 1274 n->tf_fb = NULL; 1275 free(n, M_TCPFUNCTIONS); 1276 break; 1277 } 1278 } 1279 } 1280 rw_wunlock(&tcp_function_lock); 1281 return (error); 1282 } 1283 1284 /* 1285 * Register a TCP function block using the name provided in the name 1286 * argument. 1287 * 1288 * Returns 0 on success, or an error code on failure. 1289 */ 1290 int 1291 register_tcp_functions_as_name(struct tcp_function_block *blk, const char *name, 1292 int wait) 1293 { 1294 const char *name_list[1]; 1295 int num_names, rv; 1296 1297 num_names = 1; 1298 if (name != NULL) 1299 name_list[0] = name; 1300 else 1301 name_list[0] = blk->tfb_tcp_block_name; 1302 rv = register_tcp_functions_as_names(blk, wait, name_list, &num_names); 1303 return (rv); 1304 } 1305 1306 /* 1307 * Register a TCP function block using the name defined in 1308 * blk->tfb_tcp_block_name. 1309 * 1310 * Returns 0 on success, or an error code on failure. 1311 */ 1312 int 1313 register_tcp_functions(struct tcp_function_block *blk, int wait) 1314 { 1315 1316 return (register_tcp_functions_as_name(blk, NULL, wait)); 1317 } 1318 1319 /* 1320 * Deregister all names associated with a function block. This 1321 * functionally removes the function block from use within the system. 1322 * 1323 * When called with a true quiesce argument, mark the function block 1324 * as being removed so no more stacks will use it and determine 1325 * whether the removal would succeed. 1326 * 1327 * When called with a false quiesce argument, actually attempt the 1328 * removal. 1329 * 1330 * When called with a force argument, attempt to switch all TCBs to 1331 * use the default stack instead of returning EBUSY. 1332 * 1333 * Returns 0 on success (or if the removal would succeed), or an error 1334 * code on failure. 1335 */ 1336 int 1337 deregister_tcp_functions(struct tcp_function_block *blk, bool quiesce, 1338 bool force) 1339 { 1340 struct tcp_function *f; 1341 VNET_ITERATOR_DECL(vnet_iter); 1342 1343 if (blk == &tcp_def_funcblk) { 1344 /* You can't un-register the default */ 1345 return (EPERM); 1346 } 1347 rw_wlock(&tcp_function_lock); 1348 VNET_LIST_RLOCK_NOSLEEP(); 1349 VNET_FOREACH(vnet_iter) { 1350 CURVNET_SET(vnet_iter); 1351 if (blk == V_tcp_func_set_ptr) { 1352 /* You can't free the current default in some vnet. */ 1353 CURVNET_RESTORE(); 1354 VNET_LIST_RUNLOCK_NOSLEEP(); 1355 rw_wunlock(&tcp_function_lock); 1356 return (EBUSY); 1357 } 1358 CURVNET_RESTORE(); 1359 } 1360 VNET_LIST_RUNLOCK_NOSLEEP(); 1361 /* Mark the block so no more stacks can use it. */ 1362 blk->tfb_flags |= TCP_FUNC_BEING_REMOVED; 1363 /* 1364 * If TCBs are still attached to the stack, attempt to switch them 1365 * to the default stack. 1366 */ 1367 if (force && blk->tfb_refcnt) { 1368 struct inpcb *inp; 1369 struct tcpcb *tp; 1370 VNET_ITERATOR_DECL(vnet_iter); 1371 1372 rw_wunlock(&tcp_function_lock); 1373 1374 VNET_LIST_RLOCK(); 1375 VNET_FOREACH(vnet_iter) { 1376 CURVNET_SET(vnet_iter); 1377 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, 1378 INPLOOKUP_WLOCKPCB); 1379 1380 while ((inp = inp_next(&inpi)) != NULL) { 1381 tp = intotcpcb(inp); 1382 if (tp == NULL || tp->t_fb != blk) 1383 continue; 1384 tcp_switch_back_to_default(tp); 1385 } 1386 CURVNET_RESTORE(); 1387 } 1388 VNET_LIST_RUNLOCK(); 1389 1390 rw_wlock(&tcp_function_lock); 1391 } 1392 if (blk->tfb_refcnt) { 1393 /* TCBs still attached. */ 1394 rw_wunlock(&tcp_function_lock); 1395 return (EBUSY); 1396 } 1397 if (quiesce) { 1398 /* Skip removal. */ 1399 rw_wunlock(&tcp_function_lock); 1400 return (0); 1401 } 1402 /* Remove any function names that map to this function block. */ 1403 while (find_tcp_fb_locked(blk, &f) != NULL) { 1404 TAILQ_REMOVE(&t_functions, f, tf_next); 1405 tcp_fb_cnt--; 1406 f->tf_fb = NULL; 1407 free(f, M_TCPFUNCTIONS); 1408 } 1409 rw_wunlock(&tcp_function_lock); 1410 return (0); 1411 } 1412 1413 static void 1414 tcp_drain(void) 1415 { 1416 struct epoch_tracker et; 1417 VNET_ITERATOR_DECL(vnet_iter); 1418 1419 if (!do_tcpdrain) 1420 return; 1421 1422 NET_EPOCH_ENTER(et); 1423 VNET_LIST_RLOCK_NOSLEEP(); 1424 VNET_FOREACH(vnet_iter) { 1425 CURVNET_SET(vnet_iter); 1426 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, 1427 INPLOOKUP_WLOCKPCB); 1428 struct inpcb *inpb; 1429 struct tcpcb *tcpb; 1430 1431 /* 1432 * Walk the tcpbs, if existing, and flush the reassembly queue, 1433 * if there is one... 1434 * XXX: The "Net/3" implementation doesn't imply that the TCP 1435 * reassembly queue should be flushed, but in a situation 1436 * where we're really low on mbufs, this is potentially 1437 * useful. 1438 */ 1439 while ((inpb = inp_next(&inpi)) != NULL) { 1440 if ((tcpb = intotcpcb(inpb)) != NULL) { 1441 tcp_reass_flush(tcpb); 1442 tcp_clean_sackreport(tcpb); 1443 #ifdef TCP_BLACKBOX 1444 tcp_log_drain(tcpb); 1445 #endif 1446 #ifdef TCPPCAP 1447 if (tcp_pcap_aggressive_free) { 1448 /* Free the TCP PCAP queues. */ 1449 tcp_pcap_drain(&(tcpb->t_inpkts)); 1450 tcp_pcap_drain(&(tcpb->t_outpkts)); 1451 } 1452 #endif 1453 } 1454 } 1455 CURVNET_RESTORE(); 1456 } 1457 VNET_LIST_RUNLOCK_NOSLEEP(); 1458 NET_EPOCH_EXIT(et); 1459 } 1460 1461 static void 1462 tcp_vnet_init(void *arg __unused) 1463 { 1464 1465 #ifdef TCP_HHOOK 1466 if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN, 1467 &V_tcp_hhh[HHOOK_TCP_EST_IN], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0) 1468 printf("%s: WARNING: unable to register helper hook\n", __func__); 1469 if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT, 1470 &V_tcp_hhh[HHOOK_TCP_EST_OUT], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0) 1471 printf("%s: WARNING: unable to register helper hook\n", __func__); 1472 #endif 1473 #ifdef STATS 1474 if (tcp_stats_init()) 1475 printf("%s: WARNING: unable to initialise TCP stats\n", 1476 __func__); 1477 #endif 1478 in_pcbinfo_init(&V_tcbinfo, &tcpcbstor, tcp_tcbhashsize, 1479 tcp_tcbhashsize); 1480 1481 syncache_init(); 1482 tcp_hc_init(); 1483 1484 TUNABLE_INT_FETCH("net.inet.tcp.sack.enable", &V_tcp_do_sack); 1485 V_sack_hole_zone = uma_zcreate("sackhole", sizeof(struct sackhole), 1486 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 1487 1488 tcp_fastopen_init(); 1489 1490 COUNTER_ARRAY_ALLOC(V_tcps_states, TCP_NSTATES, M_WAITOK); 1491 VNET_PCPUSTAT_ALLOC(tcpstat, M_WAITOK); 1492 1493 V_tcp_msl = TCPTV_MSL; 1494 } 1495 VNET_SYSINIT(tcp_vnet_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, 1496 tcp_vnet_init, NULL); 1497 1498 static void 1499 tcp_init(void *arg __unused) 1500 { 1501 const char *tcbhash_tuneable; 1502 int hashsize; 1503 1504 tcp_reass_global_init(); 1505 1506 /* XXX virtualize those below? */ 1507 tcp_delacktime = TCPTV_DELACK; 1508 tcp_keepinit = TCPTV_KEEP_INIT; 1509 tcp_keepidle = TCPTV_KEEP_IDLE; 1510 tcp_keepintvl = TCPTV_KEEPINTVL; 1511 tcp_maxpersistidle = TCPTV_KEEP_IDLE; 1512 tcp_rexmit_initial = TCPTV_RTOBASE; 1513 if (tcp_rexmit_initial < 1) 1514 tcp_rexmit_initial = 1; 1515 tcp_rexmit_min = TCPTV_MIN; 1516 if (tcp_rexmit_min < 1) 1517 tcp_rexmit_min = 1; 1518 tcp_persmin = TCPTV_PERSMIN; 1519 tcp_persmax = TCPTV_PERSMAX; 1520 tcp_rexmit_slop = TCPTV_CPU_VAR; 1521 tcp_finwait2_timeout = TCPTV_FINWAIT2_TIMEOUT; 1522 1523 /* Setup the tcp function block list */ 1524 TAILQ_INIT(&t_functions); 1525 rw_init(&tcp_function_lock, "tcp_func_lock"); 1526 register_tcp_functions(&tcp_def_funcblk, M_WAITOK); 1527 sx_init(&tcpoudp_lock, "TCP over UDP configuration"); 1528 #ifdef TCP_BLACKBOX 1529 /* Initialize the TCP logging data. */ 1530 tcp_log_init(); 1531 #endif 1532 arc4rand(&V_ts_offset_secret, sizeof(V_ts_offset_secret), 0); 1533 1534 if (tcp_soreceive_stream) { 1535 #ifdef INET 1536 tcp_protosw.pr_soreceive = soreceive_stream; 1537 #endif 1538 #ifdef INET6 1539 tcp6_protosw.pr_soreceive = soreceive_stream; 1540 #endif /* INET6 */ 1541 } 1542 1543 #ifdef INET6 1544 max_protohdr_grow(sizeof(struct ip6_hdr) + sizeof(struct tcphdr)); 1545 #else /* INET6 */ 1546 max_protohdr_grow(sizeof(struct tcpiphdr)); 1547 #endif /* INET6 */ 1548 1549 ISN_LOCK_INIT(); 1550 EVENTHANDLER_REGISTER(shutdown_pre_sync, tcp_fini, NULL, 1551 SHUTDOWN_PRI_DEFAULT); 1552 EVENTHANDLER_REGISTER(vm_lowmem, tcp_drain, NULL, LOWMEM_PRI_DEFAULT); 1553 EVENTHANDLER_REGISTER(mbuf_lowmem, tcp_drain, NULL, LOWMEM_PRI_DEFAULT); 1554 1555 tcp_inp_lro_direct_queue = counter_u64_alloc(M_WAITOK); 1556 tcp_inp_lro_wokeup_queue = counter_u64_alloc(M_WAITOK); 1557 tcp_inp_lro_compressed = counter_u64_alloc(M_WAITOK); 1558 tcp_inp_lro_locks_taken = counter_u64_alloc(M_WAITOK); 1559 tcp_extra_mbuf = counter_u64_alloc(M_WAITOK); 1560 tcp_would_have_but = counter_u64_alloc(M_WAITOK); 1561 tcp_comp_total = counter_u64_alloc(M_WAITOK); 1562 tcp_uncomp_total = counter_u64_alloc(M_WAITOK); 1563 tcp_bad_csums = counter_u64_alloc(M_WAITOK); 1564 #ifdef TCPPCAP 1565 tcp_pcap_init(); 1566 #endif 1567 1568 hashsize = TCBHASHSIZE; 1569 tcbhash_tuneable = "net.inet.tcp.tcbhashsize"; 1570 TUNABLE_INT_FETCH(tcbhash_tuneable, &hashsize); 1571 if (hashsize == 0) { 1572 /* 1573 * Auto tune the hash size based on maxsockets. 1574 * A perfect hash would have a 1:1 mapping 1575 * (hashsize = maxsockets) however it's been 1576 * suggested that O(2) average is better. 1577 */ 1578 hashsize = maketcp_hashsize(maxsockets / 4); 1579 /* 1580 * Our historical default is 512, 1581 * do not autotune lower than this. 1582 */ 1583 if (hashsize < 512) 1584 hashsize = 512; 1585 if (bootverbose) 1586 printf("%s: %s auto tuned to %d\n", __func__, 1587 tcbhash_tuneable, hashsize); 1588 } 1589 /* 1590 * We require a hashsize to be a power of two. 1591 * Previously if it was not a power of two we would just reset it 1592 * back to 512, which could be a nasty surprise if you did not notice 1593 * the error message. 1594 * Instead what we do is clip it to the closest power of two lower 1595 * than the specified hash value. 1596 */ 1597 if (!powerof2(hashsize)) { 1598 int oldhashsize = hashsize; 1599 1600 hashsize = maketcp_hashsize(hashsize); 1601 /* prevent absurdly low value */ 1602 if (hashsize < 16) 1603 hashsize = 16; 1604 printf("%s: WARNING: TCB hash size not a power of 2, " 1605 "clipped from %d to %d.\n", __func__, oldhashsize, 1606 hashsize); 1607 } 1608 tcp_tcbhashsize = hashsize; 1609 1610 #ifdef INET 1611 IPPROTO_REGISTER(IPPROTO_TCP, tcp_input, tcp_ctlinput); 1612 #endif 1613 #ifdef INET6 1614 IP6PROTO_REGISTER(IPPROTO_TCP, tcp6_input, tcp6_ctlinput); 1615 #endif 1616 } 1617 SYSINIT(tcp_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, tcp_init, NULL); 1618 1619 #ifdef VIMAGE 1620 static void 1621 tcp_destroy(void *unused __unused) 1622 { 1623 int n; 1624 #ifdef TCP_HHOOK 1625 int error; 1626 #endif 1627 1628 /* 1629 * All our processes are gone, all our sockets should be cleaned 1630 * up, which means, we should be past the tcp_discardcb() calls. 1631 * Sleep to let all tcpcb timers really disappear and cleanup. 1632 */ 1633 for (;;) { 1634 INP_INFO_WLOCK(&V_tcbinfo); 1635 n = V_tcbinfo.ipi_count; 1636 INP_INFO_WUNLOCK(&V_tcbinfo); 1637 if (n == 0) 1638 break; 1639 pause("tcpdes", hz / 10); 1640 } 1641 tcp_hc_destroy(); 1642 syncache_destroy(); 1643 in_pcbinfo_destroy(&V_tcbinfo); 1644 /* tcp_discardcb() clears the sack_holes up. */ 1645 uma_zdestroy(V_sack_hole_zone); 1646 1647 /* 1648 * Cannot free the zone until all tcpcbs are released as we attach 1649 * the allocations to them. 1650 */ 1651 tcp_fastopen_destroy(); 1652 1653 COUNTER_ARRAY_FREE(V_tcps_states, TCP_NSTATES); 1654 VNET_PCPUSTAT_FREE(tcpstat); 1655 1656 #ifdef TCP_HHOOK 1657 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_IN]); 1658 if (error != 0) { 1659 printf("%s: WARNING: unable to deregister helper hook " 1660 "type=%d, id=%d: error %d returned\n", __func__, 1661 HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN, error); 1662 } 1663 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_OUT]); 1664 if (error != 0) { 1665 printf("%s: WARNING: unable to deregister helper hook " 1666 "type=%d, id=%d: error %d returned\n", __func__, 1667 HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT, error); 1668 } 1669 #endif 1670 } 1671 VNET_SYSUNINIT(tcp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, tcp_destroy, NULL); 1672 #endif 1673 1674 void 1675 tcp_fini(void *xtp) 1676 { 1677 1678 } 1679 1680 /* 1681 * Fill in the IP and TCP headers for an outgoing packet, given the tcpcb. 1682 * tcp_template used to store this data in mbufs, but we now recopy it out 1683 * of the tcpcb each time to conserve mbufs. 1684 */ 1685 void 1686 tcpip_fillheaders(struct inpcb *inp, uint16_t port, void *ip_ptr, void *tcp_ptr) 1687 { 1688 struct tcphdr *th = (struct tcphdr *)tcp_ptr; 1689 1690 INP_WLOCK_ASSERT(inp); 1691 1692 #ifdef INET6 1693 if ((inp->inp_vflag & INP_IPV6) != 0) { 1694 struct ip6_hdr *ip6; 1695 1696 ip6 = (struct ip6_hdr *)ip_ptr; 1697 ip6->ip6_flow = (ip6->ip6_flow & ~IPV6_FLOWINFO_MASK) | 1698 (inp->inp_flow & IPV6_FLOWINFO_MASK); 1699 ip6->ip6_vfc = (ip6->ip6_vfc & ~IPV6_VERSION_MASK) | 1700 (IPV6_VERSION & IPV6_VERSION_MASK); 1701 if (port == 0) 1702 ip6->ip6_nxt = IPPROTO_TCP; 1703 else 1704 ip6->ip6_nxt = IPPROTO_UDP; 1705 ip6->ip6_plen = htons(sizeof(struct tcphdr)); 1706 ip6->ip6_src = inp->in6p_laddr; 1707 ip6->ip6_dst = inp->in6p_faddr; 1708 } 1709 #endif /* INET6 */ 1710 #if defined(INET6) && defined(INET) 1711 else 1712 #endif 1713 #ifdef INET 1714 { 1715 struct ip *ip; 1716 1717 ip = (struct ip *)ip_ptr; 1718 ip->ip_v = IPVERSION; 1719 ip->ip_hl = 5; 1720 ip->ip_tos = inp->inp_ip_tos; 1721 ip->ip_len = 0; 1722 ip->ip_id = 0; 1723 ip->ip_off = 0; 1724 ip->ip_ttl = inp->inp_ip_ttl; 1725 ip->ip_sum = 0; 1726 if (port == 0) 1727 ip->ip_p = IPPROTO_TCP; 1728 else 1729 ip->ip_p = IPPROTO_UDP; 1730 ip->ip_src = inp->inp_laddr; 1731 ip->ip_dst = inp->inp_faddr; 1732 } 1733 #endif /* INET */ 1734 th->th_sport = inp->inp_lport; 1735 th->th_dport = inp->inp_fport; 1736 th->th_seq = 0; 1737 th->th_ack = 0; 1738 th->th_off = 5; 1739 tcp_set_flags(th, 0); 1740 th->th_win = 0; 1741 th->th_urp = 0; 1742 th->th_sum = 0; /* in_pseudo() is called later for ipv4 */ 1743 } 1744 1745 /* 1746 * Create template to be used to send tcp packets on a connection. 1747 * Allocates an mbuf and fills in a skeletal tcp/ip header. The only 1748 * use for this function is in keepalives, which use tcp_respond. 1749 */ 1750 struct tcptemp * 1751 tcpip_maketemplate(struct inpcb *inp) 1752 { 1753 struct tcptemp *t; 1754 1755 t = malloc(sizeof(*t), M_TEMP, M_NOWAIT); 1756 if (t == NULL) 1757 return (NULL); 1758 tcpip_fillheaders(inp, 0, (void *)&t->tt_ipgen, (void *)&t->tt_t); 1759 return (t); 1760 } 1761 1762 /* 1763 * Send a single message to the TCP at address specified by 1764 * the given TCP/IP header. If m == NULL, then we make a copy 1765 * of the tcpiphdr at th and send directly to the addressed host. 1766 * This is used to force keep alive messages out using the TCP 1767 * template for a connection. If flags are given then we send 1768 * a message back to the TCP which originated the segment th, 1769 * and discard the mbuf containing it and any other attached mbufs. 1770 * 1771 * In any case the ack and sequence number of the transmitted 1772 * segment are as specified by the parameters. 1773 * 1774 * NOTE: If m != NULL, then th must point to *inside* the mbuf. 1775 */ 1776 void 1777 tcp_respond(struct tcpcb *tp, void *ipgen, struct tcphdr *th, struct mbuf *m, 1778 tcp_seq ack, tcp_seq seq, uint16_t flags) 1779 { 1780 struct tcpopt to; 1781 struct inpcb *inp; 1782 struct ip *ip; 1783 struct mbuf *optm; 1784 struct udphdr *uh = NULL; 1785 struct tcphdr *nth; 1786 struct tcp_log_buffer *lgb; 1787 u_char *optp; 1788 #ifdef INET6 1789 struct ip6_hdr *ip6; 1790 int isipv6; 1791 #endif /* INET6 */ 1792 int optlen, tlen, win, ulen; 1793 int ect = 0; 1794 bool incl_opts; 1795 uint16_t port; 1796 int output_ret; 1797 #ifdef INVARIANTS 1798 int thflags = tcp_get_flags(th); 1799 #endif 1800 1801 KASSERT(tp != NULL || m != NULL, ("tcp_respond: tp and m both NULL")); 1802 NET_EPOCH_ASSERT(); 1803 1804 #ifdef INET6 1805 isipv6 = ((struct ip *)ipgen)->ip_v == (IPV6_VERSION >> 4); 1806 ip6 = ipgen; 1807 #endif /* INET6 */ 1808 ip = ipgen; 1809 1810 if (tp != NULL) { 1811 inp = tptoinpcb(tp); 1812 INP_LOCK_ASSERT(inp); 1813 } else 1814 inp = NULL; 1815 1816 if (m != NULL) { 1817 #ifdef INET6 1818 if (isipv6 && ip6 && (ip6->ip6_nxt == IPPROTO_UDP)) 1819 port = m->m_pkthdr.tcp_tun_port; 1820 else 1821 #endif 1822 if (ip && (ip->ip_p == IPPROTO_UDP)) 1823 port = m->m_pkthdr.tcp_tun_port; 1824 else 1825 port = 0; 1826 } else 1827 port = tp->t_port; 1828 1829 incl_opts = false; 1830 win = 0; 1831 if (tp != NULL) { 1832 if (!(flags & TH_RST)) { 1833 win = sbspace(&inp->inp_socket->so_rcv); 1834 if (win > TCP_MAXWIN << tp->rcv_scale) 1835 win = TCP_MAXWIN << tp->rcv_scale; 1836 } 1837 if ((tp->t_flags & TF_NOOPT) == 0) 1838 incl_opts = true; 1839 } 1840 if (m == NULL) { 1841 m = m_gethdr(M_NOWAIT, MT_DATA); 1842 if (m == NULL) 1843 return; 1844 m->m_data += max_linkhdr; 1845 #ifdef INET6 1846 if (isipv6) { 1847 bcopy((caddr_t)ip6, mtod(m, caddr_t), 1848 sizeof(struct ip6_hdr)); 1849 ip6 = mtod(m, struct ip6_hdr *); 1850 nth = (struct tcphdr *)(ip6 + 1); 1851 if (port) { 1852 /* Insert a UDP header */ 1853 uh = (struct udphdr *)nth; 1854 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1855 uh->uh_dport = port; 1856 nth = (struct tcphdr *)(uh + 1); 1857 } 1858 } else 1859 #endif /* INET6 */ 1860 { 1861 bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip)); 1862 ip = mtod(m, struct ip *); 1863 nth = (struct tcphdr *)(ip + 1); 1864 if (port) { 1865 /* Insert a UDP header */ 1866 uh = (struct udphdr *)nth; 1867 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1868 uh->uh_dport = port; 1869 nth = (struct tcphdr *)(uh + 1); 1870 } 1871 } 1872 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr)); 1873 flags = TH_ACK; 1874 } else if ((!M_WRITABLE(m)) || (port != 0)) { 1875 struct mbuf *n; 1876 1877 /* Can't reuse 'm', allocate a new mbuf. */ 1878 n = m_gethdr(M_NOWAIT, MT_DATA); 1879 if (n == NULL) { 1880 m_freem(m); 1881 return; 1882 } 1883 1884 if (!m_dup_pkthdr(n, m, M_NOWAIT)) { 1885 m_freem(m); 1886 m_freem(n); 1887 return; 1888 } 1889 1890 n->m_data += max_linkhdr; 1891 /* m_len is set later */ 1892 #define xchg(a,b,type) { type t; t=a; a=b; b=t; } 1893 #ifdef INET6 1894 if (isipv6) { 1895 bcopy((caddr_t)ip6, mtod(n, caddr_t), 1896 sizeof(struct ip6_hdr)); 1897 ip6 = mtod(n, struct ip6_hdr *); 1898 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); 1899 nth = (struct tcphdr *)(ip6 + 1); 1900 if (port) { 1901 /* Insert a UDP header */ 1902 uh = (struct udphdr *)nth; 1903 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1904 uh->uh_dport = port; 1905 nth = (struct tcphdr *)(uh + 1); 1906 } 1907 } else 1908 #endif /* INET6 */ 1909 { 1910 bcopy((caddr_t)ip, mtod(n, caddr_t), sizeof(struct ip)); 1911 ip = mtod(n, struct ip *); 1912 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t); 1913 nth = (struct tcphdr *)(ip + 1); 1914 if (port) { 1915 /* Insert a UDP header */ 1916 uh = (struct udphdr *)nth; 1917 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1918 uh->uh_dport = port; 1919 nth = (struct tcphdr *)(uh + 1); 1920 } 1921 } 1922 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr)); 1923 xchg(nth->th_dport, nth->th_sport, uint16_t); 1924 th = nth; 1925 m_freem(m); 1926 m = n; 1927 } else { 1928 /* 1929 * reuse the mbuf. 1930 * XXX MRT We inherit the FIB, which is lucky. 1931 */ 1932 m_freem(m->m_next); 1933 m->m_next = NULL; 1934 m->m_data = (caddr_t)ipgen; 1935 /* m_len is set later */ 1936 #ifdef INET6 1937 if (isipv6) { 1938 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); 1939 nth = (struct tcphdr *)(ip6 + 1); 1940 } else 1941 #endif /* INET6 */ 1942 { 1943 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t); 1944 nth = (struct tcphdr *)(ip + 1); 1945 } 1946 if (th != nth) { 1947 /* 1948 * this is usually a case when an extension header 1949 * exists between the IPv6 header and the 1950 * TCP header. 1951 */ 1952 nth->th_sport = th->th_sport; 1953 nth->th_dport = th->th_dport; 1954 } 1955 xchg(nth->th_dport, nth->th_sport, uint16_t); 1956 #undef xchg 1957 } 1958 tlen = 0; 1959 #ifdef INET6 1960 if (isipv6) 1961 tlen = sizeof (struct ip6_hdr) + sizeof (struct tcphdr); 1962 #endif 1963 #if defined(INET) && defined(INET6) 1964 else 1965 #endif 1966 #ifdef INET 1967 tlen = sizeof (struct tcpiphdr); 1968 #endif 1969 if (port) 1970 tlen += sizeof (struct udphdr); 1971 #ifdef INVARIANTS 1972 m->m_len = 0; 1973 KASSERT(M_TRAILINGSPACE(m) >= tlen, 1974 ("Not enough trailing space for message (m=%p, need=%d, have=%ld)", 1975 m, tlen, (long)M_TRAILINGSPACE(m))); 1976 #endif 1977 m->m_len = tlen; 1978 to.to_flags = 0; 1979 if (incl_opts) { 1980 ect = tcp_ecn_output_established(tp, &flags, 0, false); 1981 /* Make sure we have room. */ 1982 if (M_TRAILINGSPACE(m) < TCP_MAXOLEN) { 1983 m->m_next = m_get(M_NOWAIT, MT_DATA); 1984 if (m->m_next) { 1985 optp = mtod(m->m_next, u_char *); 1986 optm = m->m_next; 1987 } else 1988 incl_opts = false; 1989 } else { 1990 optp = (u_char *) (nth + 1); 1991 optm = m; 1992 } 1993 } 1994 if (incl_opts) { 1995 /* Timestamps. */ 1996 if (tp->t_flags & TF_RCVD_TSTMP) { 1997 to.to_tsval = tcp_ts_getticks() + tp->ts_offset; 1998 to.to_tsecr = tp->ts_recent; 1999 to.to_flags |= TOF_TS; 2000 } 2001 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 2002 /* TCP-MD5 (RFC2385). */ 2003 if (tp->t_flags & TF_SIGNATURE) 2004 to.to_flags |= TOF_SIGNATURE; 2005 #endif 2006 /* Add the options. */ 2007 tlen += optlen = tcp_addoptions(&to, optp); 2008 2009 /* Update m_len in the correct mbuf. */ 2010 optm->m_len += optlen; 2011 } else 2012 optlen = 0; 2013 #ifdef INET6 2014 if (isipv6) { 2015 if (uh) { 2016 ulen = tlen - sizeof(struct ip6_hdr); 2017 uh->uh_ulen = htons(ulen); 2018 } 2019 ip6->ip6_flow = htonl(ect << IPV6_FLOWLABEL_LEN); 2020 ip6->ip6_vfc = IPV6_VERSION; 2021 if (port) 2022 ip6->ip6_nxt = IPPROTO_UDP; 2023 else 2024 ip6->ip6_nxt = IPPROTO_TCP; 2025 ip6->ip6_plen = htons(tlen - sizeof(*ip6)); 2026 } 2027 #endif 2028 #if defined(INET) && defined(INET6) 2029 else 2030 #endif 2031 #ifdef INET 2032 { 2033 if (uh) { 2034 ulen = tlen - sizeof(struct ip); 2035 uh->uh_ulen = htons(ulen); 2036 } 2037 ip->ip_tos = ect; 2038 ip->ip_len = htons(tlen); 2039 ip->ip_ttl = V_ip_defttl; 2040 if (port) { 2041 ip->ip_p = IPPROTO_UDP; 2042 } else { 2043 ip->ip_p = IPPROTO_TCP; 2044 } 2045 if (V_path_mtu_discovery) 2046 ip->ip_off |= htons(IP_DF); 2047 } 2048 #endif 2049 m->m_pkthdr.len = tlen; 2050 m->m_pkthdr.rcvif = NULL; 2051 #ifdef MAC 2052 if (inp != NULL) { 2053 /* 2054 * Packet is associated with a socket, so allow the 2055 * label of the response to reflect the socket label. 2056 */ 2057 INP_LOCK_ASSERT(inp); 2058 mac_inpcb_create_mbuf(inp, m); 2059 } else { 2060 /* 2061 * Packet is not associated with a socket, so possibly 2062 * update the label in place. 2063 */ 2064 mac_netinet_tcp_reply(m); 2065 } 2066 #endif 2067 nth->th_seq = htonl(seq); 2068 nth->th_ack = htonl(ack); 2069 nth->th_off = (sizeof (struct tcphdr) + optlen) >> 2; 2070 tcp_set_flags(nth, flags); 2071 if (tp != NULL) 2072 nth->th_win = htons((u_short) (win >> tp->rcv_scale)); 2073 else 2074 nth->th_win = htons((u_short)win); 2075 nth->th_urp = 0; 2076 2077 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 2078 if (to.to_flags & TOF_SIGNATURE) { 2079 if (!TCPMD5_ENABLED() || 2080 TCPMD5_OUTPUT(m, nth, to.to_signature) != 0) { 2081 m_freem(m); 2082 return; 2083 } 2084 } 2085 #endif 2086 2087 #ifdef INET6 2088 if (isipv6) { 2089 if (port) { 2090 m->m_pkthdr.csum_flags = CSUM_UDP_IPV6; 2091 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 2092 uh->uh_sum = in6_cksum_pseudo(ip6, ulen, IPPROTO_UDP, 0); 2093 nth->th_sum = 0; 2094 } else { 2095 m->m_pkthdr.csum_flags = CSUM_TCP_IPV6; 2096 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); 2097 nth->th_sum = in6_cksum_pseudo(ip6, 2098 tlen - sizeof(struct ip6_hdr), IPPROTO_TCP, 0); 2099 } 2100 ip6->ip6_hlim = in6_selecthlim(inp, NULL); 2101 } 2102 #endif /* INET6 */ 2103 #if defined(INET6) && defined(INET) 2104 else 2105 #endif 2106 #ifdef INET 2107 { 2108 if (port) { 2109 uh->uh_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, 2110 htons(ulen + IPPROTO_UDP)); 2111 m->m_pkthdr.csum_flags = CSUM_UDP; 2112 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 2113 nth->th_sum = 0; 2114 } else { 2115 m->m_pkthdr.csum_flags = CSUM_TCP; 2116 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); 2117 nth->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, 2118 htons((u_short)(tlen - sizeof(struct ip) + ip->ip_p))); 2119 } 2120 } 2121 #endif /* INET */ 2122 TCP_PROBE3(debug__output, tp, th, m); 2123 if (flags & TH_RST) 2124 TCP_PROBE5(accept__refused, NULL, NULL, m, tp, nth); 2125 lgb = NULL; 2126 if ((tp != NULL) && tcp_bblogging_on(tp)) { 2127 if (INP_WLOCKED(inp)) { 2128 union tcp_log_stackspecific log; 2129 struct timeval tv; 2130 2131 memset(&log.u_bbr, 0, sizeof(log.u_bbr)); 2132 log.u_bbr.inhpts = inp->inp_in_hpts; 2133 log.u_bbr.flex8 = 4; 2134 log.u_bbr.pkts_out = tp->t_maxseg; 2135 log.u_bbr.timeStamp = tcp_get_usecs(&tv); 2136 log.u_bbr.delivered = 0; 2137 lgb = tcp_log_event(tp, nth, NULL, NULL, TCP_LOG_OUT, 2138 ERRNO_UNK, 0, &log, false, NULL, NULL, 0, &tv); 2139 } else { 2140 /* 2141 * We can not log the packet, since we only own the 2142 * read lock, but a write lock is needed. The read lock 2143 * is not upgraded to a write lock, since only getting 2144 * the read lock was done intentionally to improve the 2145 * handling of SYN flooding attacks. 2146 * This happens only for pure SYN segments received in 2147 * the initial CLOSED state, or received in a more 2148 * advanced state than listen and the UDP encapsulation 2149 * port is unexpected. 2150 * The incoming SYN segments do not really belong to 2151 * the TCP connection and the handling does not change 2152 * the state of the TCP connection. Therefore, the 2153 * sending of the RST segments is not logged. Please 2154 * note that also the incoming SYN segments are not 2155 * logged. 2156 * 2157 * The following code ensures that the above description 2158 * is and stays correct. 2159 */ 2160 KASSERT((thflags & (TH_ACK|TH_SYN)) == TH_SYN && 2161 (tp->t_state == TCPS_CLOSED || 2162 (tp->t_state > TCPS_LISTEN && tp->t_port != port)), 2163 ("%s: Logging of TCP segment with flags 0x%b and " 2164 "UDP encapsulation port %u skipped in state %s", 2165 __func__, thflags, PRINT_TH_FLAGS, 2166 ntohs(port), tcpstates[tp->t_state])); 2167 } 2168 } 2169 2170 if (flags & TH_ACK) 2171 TCPSTAT_INC(tcps_sndacks); 2172 else if (flags & (TH_SYN|TH_FIN|TH_RST)) 2173 TCPSTAT_INC(tcps_sndctrl); 2174 TCPSTAT_INC(tcps_sndtotal); 2175 2176 #ifdef INET6 2177 if (isipv6) { 2178 TCP_PROBE5(send, NULL, tp, ip6, tp, nth); 2179 output_ret = ip6_output(m, NULL, NULL, 0, NULL, NULL, inp); 2180 } 2181 #endif /* INET6 */ 2182 #if defined(INET) && defined(INET6) 2183 else 2184 #endif 2185 #ifdef INET 2186 { 2187 TCP_PROBE5(send, NULL, tp, ip, tp, nth); 2188 output_ret = ip_output(m, NULL, NULL, 0, NULL, inp); 2189 } 2190 #endif 2191 if (lgb != NULL) 2192 lgb->tlb_errno = output_ret; 2193 } 2194 2195 /* 2196 * Create a new TCP control block, making an empty reassembly queue and hooking 2197 * it to the argument protocol control block. The `inp' parameter must have 2198 * come from the zone allocator set up by tcpcbstor declaration. 2199 */ 2200 struct tcpcb * 2201 tcp_newtcpcb(struct inpcb *inp) 2202 { 2203 struct tcpcb *tp = intotcpcb(inp); 2204 #ifdef INET6 2205 int isipv6 = (inp->inp_vflag & INP_IPV6) != 0; 2206 #endif /* INET6 */ 2207 2208 /* 2209 * Historically allocation was done with M_ZERO. There is a lot of 2210 * code that rely on that. For now take safe approach and zero whole 2211 * tcpcb. This definitely can be optimized. 2212 */ 2213 bzero(&tp->t_start_zero, t_zero_size); 2214 2215 /* Initialise cc_var struct for this tcpcb. */ 2216 tp->t_ccv.type = IPPROTO_TCP; 2217 tp->t_ccv.ccvc.tcp = tp; 2218 rw_rlock(&tcp_function_lock); 2219 tp->t_fb = V_tcp_func_set_ptr; 2220 refcount_acquire(&tp->t_fb->tfb_refcnt); 2221 rw_runlock(&tcp_function_lock); 2222 /* 2223 * Use the current system default CC algorithm. 2224 */ 2225 cc_attach(tp, CC_DEFAULT_ALGO()); 2226 2227 if (CC_ALGO(tp)->cb_init != NULL) 2228 if (CC_ALGO(tp)->cb_init(&tp->t_ccv, NULL) > 0) { 2229 cc_detach(tp); 2230 if (tp->t_fb->tfb_tcp_fb_fini) 2231 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); 2232 refcount_release(&tp->t_fb->tfb_refcnt); 2233 return (NULL); 2234 } 2235 2236 #ifdef TCP_HHOOK 2237 if (khelp_init_osd(HELPER_CLASS_TCP, &tp->t_osd)) { 2238 if (tp->t_fb->tfb_tcp_fb_fini) 2239 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); 2240 refcount_release(&tp->t_fb->tfb_refcnt); 2241 return (NULL); 2242 } 2243 #endif 2244 2245 TAILQ_INIT(&tp->t_segq); 2246 tp->t_maxseg = 2247 #ifdef INET6 2248 isipv6 ? V_tcp_v6mssdflt : 2249 #endif /* INET6 */ 2250 V_tcp_mssdflt; 2251 2252 callout_init_rw(&tp->t_callout, &inp->inp_lock, CALLOUT_RETURNUNLOCKED); 2253 for (int i = 0; i < TT_N; i++) 2254 tp->t_timers[i] = SBT_MAX; 2255 2256 switch (V_tcp_do_rfc1323) { 2257 case 0: 2258 break; 2259 default: 2260 case 1: 2261 tp->t_flags = (TF_REQ_SCALE|TF_REQ_TSTMP); 2262 break; 2263 case 2: 2264 tp->t_flags = TF_REQ_SCALE; 2265 break; 2266 case 3: 2267 tp->t_flags = TF_REQ_TSTMP; 2268 break; 2269 } 2270 if (V_tcp_do_sack) 2271 tp->t_flags |= TF_SACK_PERMIT; 2272 TAILQ_INIT(&tp->snd_holes); 2273 2274 /* 2275 * Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no 2276 * rtt estimate. Set rttvar so that srtt + 4 * rttvar gives 2277 * reasonable initial retransmit time. 2278 */ 2279 tp->t_srtt = TCPTV_SRTTBASE; 2280 tp->t_rttvar = ((tcp_rexmit_initial - TCPTV_SRTTBASE) << TCP_RTTVAR_SHIFT) / 4; 2281 tp->t_rttmin = tcp_rexmit_min; 2282 tp->t_rxtcur = tcp_rexmit_initial; 2283 tp->snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT; 2284 tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT; 2285 tp->t_rcvtime = ticks; 2286 /* We always start with ticks granularity */ 2287 tp->t_tmr_granularity = TCP_TMR_GRANULARITY_TICKS; 2288 /* 2289 * IPv4 TTL initialization is necessary for an IPv6 socket as well, 2290 * because the socket may be bound to an IPv6 wildcard address, 2291 * which may match an IPv4-mapped IPv6 address. 2292 */ 2293 inp->inp_ip_ttl = V_ip_defttl; 2294 #ifdef TCPHPTS 2295 /* 2296 * If using hpts lets drop a random number in so 2297 * not all new connections fall on the same CPU. 2298 */ 2299 inp->inp_hpts_cpu = hpts_random_cpu(inp); 2300 #endif 2301 #ifdef TCPPCAP 2302 /* 2303 * Init the TCP PCAP queues. 2304 */ 2305 tcp_pcap_tcpcb_init(tp); 2306 #endif 2307 #ifdef TCP_BLACKBOX 2308 /* Initialize the per-TCPCB log data. */ 2309 tcp_log_tcpcbinit(tp); 2310 #endif 2311 tp->t_pacing_rate = -1; 2312 if (tp->t_fb->tfb_tcp_fb_init) { 2313 if ((*tp->t_fb->tfb_tcp_fb_init)(tp, &tp->t_fb_ptr)) { 2314 refcount_release(&tp->t_fb->tfb_refcnt); 2315 return (NULL); 2316 } 2317 } 2318 #ifdef STATS 2319 if (V_tcp_perconn_stats_enable == 1) 2320 tp->t_stats = stats_blob_alloc(V_tcp_perconn_stats_dflt_tpl, 0); 2321 #endif 2322 if (V_tcp_do_lrd) 2323 tp->t_flags |= TF_LRD; 2324 2325 return (tp); 2326 } 2327 2328 /* 2329 * Drop a TCP connection, reporting 2330 * the specified error. If connection is synchronized, 2331 * then send a RST to peer. 2332 */ 2333 struct tcpcb * 2334 tcp_drop(struct tcpcb *tp, int errno) 2335 { 2336 struct socket *so = tptosocket(tp); 2337 2338 NET_EPOCH_ASSERT(); 2339 INP_WLOCK_ASSERT(tptoinpcb(tp)); 2340 2341 if (TCPS_HAVERCVDSYN(tp->t_state)) { 2342 tcp_state_change(tp, TCPS_CLOSED); 2343 /* Don't use tcp_output() here due to possible recursion. */ 2344 (void)tcp_output_nodrop(tp); 2345 TCPSTAT_INC(tcps_drops); 2346 } else 2347 TCPSTAT_INC(tcps_conndrops); 2348 if (errno == ETIMEDOUT && tp->t_softerror) 2349 errno = tp->t_softerror; 2350 so->so_error = errno; 2351 return (tcp_close(tp)); 2352 } 2353 2354 void 2355 tcp_discardcb(struct tcpcb *tp) 2356 { 2357 struct inpcb *inp = tptoinpcb(tp); 2358 struct socket *so = tptosocket(tp); 2359 #ifdef INET6 2360 bool isipv6 = (inp->inp_vflag & INP_IPV6) != 0; 2361 #endif 2362 2363 INP_WLOCK_ASSERT(inp); 2364 2365 tcp_timer_stop(tp); 2366 if (tp->t_fb->tfb_tcp_timer_stop_all) { 2367 tp->t_fb->tfb_tcp_timer_stop_all(tp); 2368 } 2369 2370 /* free the reassembly queue, if any */ 2371 tcp_reass_flush(tp); 2372 2373 #ifdef TCP_OFFLOAD 2374 /* Disconnect offload device, if any. */ 2375 if (tp->t_flags & TF_TOE) 2376 tcp_offload_detach(tp); 2377 #endif 2378 2379 tcp_free_sackholes(tp); 2380 2381 #ifdef TCPPCAP 2382 /* Free the TCP PCAP queues. */ 2383 tcp_pcap_drain(&(tp->t_inpkts)); 2384 tcp_pcap_drain(&(tp->t_outpkts)); 2385 #endif 2386 2387 /* Allow the CC algorithm to clean up after itself. */ 2388 if (CC_ALGO(tp)->cb_destroy != NULL) 2389 CC_ALGO(tp)->cb_destroy(&tp->t_ccv); 2390 CC_DATA(tp) = NULL; 2391 /* Detach from the CC algorithm */ 2392 cc_detach(tp); 2393 2394 #ifdef TCP_HHOOK 2395 khelp_destroy_osd(&tp->t_osd); 2396 #endif 2397 #ifdef STATS 2398 stats_blob_destroy(tp->t_stats); 2399 #endif 2400 2401 CC_ALGO(tp) = NULL; 2402 2403 #ifdef TCP_BLACKBOX 2404 tcp_log_tcpcbfini(tp); 2405 #endif 2406 TCPSTATES_DEC(tp->t_state); 2407 if (tp->t_fb->tfb_tcp_fb_fini) 2408 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); 2409 2410 /* 2411 * If we got enough samples through the srtt filter, 2412 * save the rtt and rttvar in the routing entry. 2413 * 'Enough' is arbitrarily defined as 4 rtt samples. 2414 * 4 samples is enough for the srtt filter to converge 2415 * to within enough % of the correct value; fewer samples 2416 * and we could save a bogus rtt. The danger is not high 2417 * as tcp quickly recovers from everything. 2418 * XXX: Works very well but needs some more statistics! 2419 * 2420 * XXXRRS: Updating must be after the stack fini() since 2421 * that may be converting some internal representation of 2422 * say srtt etc into the general one used by other stacks. 2423 * Lets also at least protect against the so being NULL 2424 * as RW stated below. 2425 */ 2426 if ((tp->t_rttupdated >= 4) && (so != NULL)) { 2427 struct hc_metrics_lite metrics; 2428 uint32_t ssthresh; 2429 2430 bzero(&metrics, sizeof(metrics)); 2431 /* 2432 * Update the ssthresh always when the conditions below 2433 * are satisfied. This gives us better new start value 2434 * for the congestion avoidance for new connections. 2435 * ssthresh is only set if packet loss occurred on a session. 2436 * 2437 * XXXRW: 'so' may be NULL here, and/or socket buffer may be 2438 * being torn down. Ideally this code would not use 'so'. 2439 */ 2440 ssthresh = tp->snd_ssthresh; 2441 if (ssthresh != 0 && ssthresh < so->so_snd.sb_hiwat / 2) { 2442 /* 2443 * convert the limit from user data bytes to 2444 * packets then to packet data bytes. 2445 */ 2446 ssthresh = (ssthresh + tp->t_maxseg / 2) / tp->t_maxseg; 2447 if (ssthresh < 2) 2448 ssthresh = 2; 2449 ssthresh *= (tp->t_maxseg + 2450 #ifdef INET6 2451 (isipv6 ? sizeof (struct ip6_hdr) + 2452 sizeof (struct tcphdr) : 2453 #endif 2454 sizeof (struct tcpiphdr) 2455 #ifdef INET6 2456 ) 2457 #endif 2458 ); 2459 } else 2460 ssthresh = 0; 2461 metrics.rmx_ssthresh = ssthresh; 2462 2463 metrics.rmx_rtt = tp->t_srtt; 2464 metrics.rmx_rttvar = tp->t_rttvar; 2465 metrics.rmx_cwnd = tp->snd_cwnd; 2466 metrics.rmx_sendpipe = 0; 2467 metrics.rmx_recvpipe = 0; 2468 2469 tcp_hc_update(&inp->inp_inc, &metrics); 2470 } 2471 2472 refcount_release(&tp->t_fb->tfb_refcnt); 2473 } 2474 2475 /* 2476 * Attempt to close a TCP control block, marking it as dropped, and freeing 2477 * the socket if we hold the only reference. 2478 */ 2479 struct tcpcb * 2480 tcp_close(struct tcpcb *tp) 2481 { 2482 struct inpcb *inp = tptoinpcb(tp); 2483 struct socket *so = tptosocket(tp); 2484 2485 INP_WLOCK_ASSERT(inp); 2486 2487 #ifdef TCP_OFFLOAD 2488 if (tp->t_state == TCPS_LISTEN) 2489 tcp_offload_listen_stop(tp); 2490 #endif 2491 /* 2492 * This releases the TFO pending counter resource for TFO listen 2493 * sockets as well as passively-created TFO sockets that transition 2494 * from SYN_RECEIVED to CLOSED. 2495 */ 2496 if (tp->t_tfo_pending) { 2497 tcp_fastopen_decrement_counter(tp->t_tfo_pending); 2498 tp->t_tfo_pending = NULL; 2499 } 2500 #ifdef TCPHPTS 2501 tcp_hpts_remove(inp); 2502 #endif 2503 in_pcbdrop(inp); 2504 TCPSTAT_INC(tcps_closed); 2505 if (tp->t_state != TCPS_CLOSED) 2506 tcp_state_change(tp, TCPS_CLOSED); 2507 KASSERT(inp->inp_socket != NULL, ("tcp_close: inp_socket NULL")); 2508 soisdisconnected(so); 2509 if (inp->inp_flags & INP_SOCKREF) { 2510 inp->inp_flags &= ~INP_SOCKREF; 2511 INP_WUNLOCK(inp); 2512 sorele(so); 2513 return (NULL); 2514 } 2515 return (tp); 2516 } 2517 2518 /* 2519 * Notify a tcp user of an asynchronous error; 2520 * store error as soft error, but wake up user 2521 * (for now, won't do anything until can select for soft error). 2522 * 2523 * Do not wake up user since there currently is no mechanism for 2524 * reporting soft errors (yet - a kqueue filter may be added). 2525 */ 2526 static struct inpcb * 2527 tcp_notify(struct inpcb *inp, int error) 2528 { 2529 struct tcpcb *tp; 2530 2531 INP_WLOCK_ASSERT(inp); 2532 2533 tp = intotcpcb(inp); 2534 KASSERT(tp != NULL, ("tcp_notify: tp == NULL")); 2535 2536 /* 2537 * Ignore some errors if we are hooked up. 2538 * If connection hasn't completed, has retransmitted several times, 2539 * and receives a second error, give up now. This is better 2540 * than waiting a long time to establish a connection that 2541 * can never complete. 2542 */ 2543 if (tp->t_state == TCPS_ESTABLISHED && 2544 (error == EHOSTUNREACH || error == ENETUNREACH || 2545 error == EHOSTDOWN)) { 2546 if (inp->inp_route.ro_nh) { 2547 NH_FREE(inp->inp_route.ro_nh); 2548 inp->inp_route.ro_nh = (struct nhop_object *)NULL; 2549 } 2550 return (inp); 2551 } else if (tp->t_state < TCPS_ESTABLISHED && tp->t_rxtshift > 3 && 2552 tp->t_softerror) { 2553 tp = tcp_drop(tp, error); 2554 if (tp != NULL) 2555 return (inp); 2556 else 2557 return (NULL); 2558 } else { 2559 tp->t_softerror = error; 2560 return (inp); 2561 } 2562 #if 0 2563 wakeup( &so->so_timeo); 2564 sorwakeup(so); 2565 sowwakeup(so); 2566 #endif 2567 } 2568 2569 static int 2570 tcp_pcblist(SYSCTL_HANDLER_ARGS) 2571 { 2572 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, 2573 INPLOOKUP_RLOCKPCB); 2574 struct xinpgen xig; 2575 struct inpcb *inp; 2576 int error; 2577 2578 if (req->newptr != NULL) 2579 return (EPERM); 2580 2581 if (req->oldptr == NULL) { 2582 int n; 2583 2584 n = V_tcbinfo.ipi_count + 2585 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); 2586 n += imax(n / 8, 10); 2587 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xtcpcb); 2588 return (0); 2589 } 2590 2591 if ((error = sysctl_wire_old_buffer(req, 0)) != 0) 2592 return (error); 2593 2594 bzero(&xig, sizeof(xig)); 2595 xig.xig_len = sizeof xig; 2596 xig.xig_count = V_tcbinfo.ipi_count + 2597 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); 2598 xig.xig_gen = V_tcbinfo.ipi_gencnt; 2599 xig.xig_sogen = so_gencnt; 2600 error = SYSCTL_OUT(req, &xig, sizeof xig); 2601 if (error) 2602 return (error); 2603 2604 error = syncache_pcblist(req); 2605 if (error) 2606 return (error); 2607 2608 while ((inp = inp_next(&inpi)) != NULL) { 2609 if (inp->inp_gencnt <= xig.xig_gen && 2610 cr_canseeinpcb(req->td->td_ucred, inp) == 0) { 2611 struct xtcpcb xt; 2612 2613 tcp_inptoxtp(inp, &xt); 2614 error = SYSCTL_OUT(req, &xt, sizeof xt); 2615 if (error) { 2616 INP_RUNLOCK(inp); 2617 break; 2618 } else 2619 continue; 2620 } 2621 } 2622 2623 if (!error) { 2624 /* 2625 * Give the user an updated idea of our state. 2626 * If the generation differs from what we told 2627 * her before, she knows that something happened 2628 * while we were processing this request, and it 2629 * might be necessary to retry. 2630 */ 2631 xig.xig_gen = V_tcbinfo.ipi_gencnt; 2632 xig.xig_sogen = so_gencnt; 2633 xig.xig_count = V_tcbinfo.ipi_count + 2634 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); 2635 error = SYSCTL_OUT(req, &xig, sizeof xig); 2636 } 2637 2638 return (error); 2639 } 2640 2641 SYSCTL_PROC(_net_inet_tcp, TCPCTL_PCBLIST, pcblist, 2642 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_NEEDGIANT, 2643 NULL, 0, tcp_pcblist, "S,xtcpcb", 2644 "List of active TCP connections"); 2645 2646 #ifdef INET 2647 static int 2648 tcp_getcred(SYSCTL_HANDLER_ARGS) 2649 { 2650 struct xucred xuc; 2651 struct sockaddr_in addrs[2]; 2652 struct epoch_tracker et; 2653 struct inpcb *inp; 2654 int error; 2655 2656 error = priv_check(req->td, PRIV_NETINET_GETCRED); 2657 if (error) 2658 return (error); 2659 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 2660 if (error) 2661 return (error); 2662 NET_EPOCH_ENTER(et); 2663 inp = in_pcblookup(&V_tcbinfo, addrs[1].sin_addr, addrs[1].sin_port, 2664 addrs[0].sin_addr, addrs[0].sin_port, INPLOOKUP_RLOCKPCB, NULL); 2665 NET_EPOCH_EXIT(et); 2666 if (inp != NULL) { 2667 if (error == 0) 2668 error = cr_canseeinpcb(req->td->td_ucred, inp); 2669 if (error == 0) 2670 cru2x(inp->inp_cred, &xuc); 2671 INP_RUNLOCK(inp); 2672 } else 2673 error = ENOENT; 2674 if (error == 0) 2675 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 2676 return (error); 2677 } 2678 2679 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, getcred, 2680 CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_NEEDGIANT, 2681 0, 0, tcp_getcred, "S,xucred", 2682 "Get the xucred of a TCP connection"); 2683 #endif /* INET */ 2684 2685 #ifdef INET6 2686 static int 2687 tcp6_getcred(SYSCTL_HANDLER_ARGS) 2688 { 2689 struct epoch_tracker et; 2690 struct xucred xuc; 2691 struct sockaddr_in6 addrs[2]; 2692 struct inpcb *inp; 2693 int error; 2694 #ifdef INET 2695 int mapped = 0; 2696 #endif 2697 2698 error = priv_check(req->td, PRIV_NETINET_GETCRED); 2699 if (error) 2700 return (error); 2701 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 2702 if (error) 2703 return (error); 2704 if ((error = sa6_embedscope(&addrs[0], V_ip6_use_defzone)) != 0 || 2705 (error = sa6_embedscope(&addrs[1], V_ip6_use_defzone)) != 0) { 2706 return (error); 2707 } 2708 if (IN6_IS_ADDR_V4MAPPED(&addrs[0].sin6_addr)) { 2709 #ifdef INET 2710 if (IN6_IS_ADDR_V4MAPPED(&addrs[1].sin6_addr)) 2711 mapped = 1; 2712 else 2713 #endif 2714 return (EINVAL); 2715 } 2716 2717 NET_EPOCH_ENTER(et); 2718 #ifdef INET 2719 if (mapped == 1) 2720 inp = in_pcblookup(&V_tcbinfo, 2721 *(struct in_addr *)&addrs[1].sin6_addr.s6_addr[12], 2722 addrs[1].sin6_port, 2723 *(struct in_addr *)&addrs[0].sin6_addr.s6_addr[12], 2724 addrs[0].sin6_port, INPLOOKUP_RLOCKPCB, NULL); 2725 else 2726 #endif 2727 inp = in6_pcblookup(&V_tcbinfo, 2728 &addrs[1].sin6_addr, addrs[1].sin6_port, 2729 &addrs[0].sin6_addr, addrs[0].sin6_port, 2730 INPLOOKUP_RLOCKPCB, NULL); 2731 NET_EPOCH_EXIT(et); 2732 if (inp != NULL) { 2733 if (error == 0) 2734 error = cr_canseeinpcb(req->td->td_ucred, inp); 2735 if (error == 0) 2736 cru2x(inp->inp_cred, &xuc); 2737 INP_RUNLOCK(inp); 2738 } else 2739 error = ENOENT; 2740 if (error == 0) 2741 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 2742 return (error); 2743 } 2744 2745 SYSCTL_PROC(_net_inet6_tcp6, OID_AUTO, getcred, 2746 CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_NEEDGIANT, 2747 0, 0, tcp6_getcred, "S,xucred", 2748 "Get the xucred of a TCP6 connection"); 2749 #endif /* INET6 */ 2750 2751 #ifdef INET 2752 /* Path MTU to try next when a fragmentation-needed message is received. */ 2753 static inline int 2754 tcp_next_pmtu(const struct icmp *icp, const struct ip *ip) 2755 { 2756 int mtu = ntohs(icp->icmp_nextmtu); 2757 2758 /* If no alternative MTU was proposed, try the next smaller one. */ 2759 if (!mtu) 2760 mtu = ip_next_mtu(ntohs(ip->ip_len), 1); 2761 if (mtu < V_tcp_minmss + sizeof(struct tcpiphdr)) 2762 mtu = V_tcp_minmss + sizeof(struct tcpiphdr); 2763 2764 return (mtu); 2765 } 2766 2767 static void 2768 tcp_ctlinput_with_port(struct icmp *icp, uint16_t port) 2769 { 2770 struct ip *ip; 2771 struct tcphdr *th; 2772 struct inpcb *inp; 2773 struct tcpcb *tp; 2774 struct inpcb *(*notify)(struct inpcb *, int); 2775 struct in_conninfo inc; 2776 tcp_seq icmp_tcp_seq; 2777 int errno, mtu; 2778 2779 errno = icmp_errmap(icp); 2780 switch (errno) { 2781 case 0: 2782 return; 2783 case EMSGSIZE: 2784 notify = tcp_mtudisc_notify; 2785 break; 2786 case ECONNREFUSED: 2787 if (V_icmp_may_rst) 2788 notify = tcp_drop_syn_sent; 2789 else 2790 notify = tcp_notify; 2791 break; 2792 case EHOSTUNREACH: 2793 if (V_icmp_may_rst && icp->icmp_type == ICMP_TIMXCEED) 2794 notify = tcp_drop_syn_sent; 2795 else 2796 notify = tcp_notify; 2797 break; 2798 default: 2799 notify = tcp_notify; 2800 } 2801 2802 ip = &icp->icmp_ip; 2803 th = (struct tcphdr *)((caddr_t)ip + (ip->ip_hl << 2)); 2804 icmp_tcp_seq = th->th_seq; 2805 inp = in_pcblookup(&V_tcbinfo, ip->ip_dst, th->th_dport, ip->ip_src, 2806 th->th_sport, INPLOOKUP_WLOCKPCB, NULL); 2807 if (inp != NULL) { 2808 tp = intotcpcb(inp); 2809 #ifdef TCP_OFFLOAD 2810 if (tp->t_flags & TF_TOE && errno == EMSGSIZE) { 2811 /* 2812 * MTU discovery for offloaded connections. Let 2813 * the TOE driver verify seq# and process it. 2814 */ 2815 mtu = tcp_next_pmtu(icp, ip); 2816 tcp_offload_pmtu_update(tp, icmp_tcp_seq, mtu); 2817 goto out; 2818 } 2819 #endif 2820 if (tp->t_port != port) 2821 goto out; 2822 if (SEQ_GEQ(ntohl(icmp_tcp_seq), tp->snd_una) && 2823 SEQ_LT(ntohl(icmp_tcp_seq), tp->snd_max)) { 2824 if (errno == EMSGSIZE) { 2825 /* 2826 * MTU discovery: we got a needfrag and 2827 * will potentially try a lower MTU. 2828 */ 2829 mtu = tcp_next_pmtu(icp, ip); 2830 2831 /* 2832 * Only process the offered MTU if it 2833 * is smaller than the current one. 2834 */ 2835 if (mtu < tp->t_maxseg + 2836 sizeof(struct tcpiphdr)) { 2837 bzero(&inc, sizeof(inc)); 2838 inc.inc_faddr = ip->ip_dst; 2839 inc.inc_fibnum = 2840 inp->inp_inc.inc_fibnum; 2841 tcp_hc_updatemtu(&inc, mtu); 2842 inp = tcp_mtudisc(inp, mtu); 2843 } 2844 } else 2845 inp = (*notify)(inp, errno); 2846 } 2847 } else { 2848 bzero(&inc, sizeof(inc)); 2849 inc.inc_fport = th->th_dport; 2850 inc.inc_lport = th->th_sport; 2851 inc.inc_faddr = ip->ip_dst; 2852 inc.inc_laddr = ip->ip_src; 2853 syncache_unreach(&inc, icmp_tcp_seq, port); 2854 } 2855 out: 2856 if (inp != NULL) 2857 INP_WUNLOCK(inp); 2858 } 2859 2860 static void 2861 tcp_ctlinput(struct icmp *icmp) 2862 { 2863 tcp_ctlinput_with_port(icmp, htons(0)); 2864 } 2865 2866 static void 2867 tcp_ctlinput_viaudp(udp_tun_icmp_param_t param) 2868 { 2869 /* Its a tunneled TCP over UDP icmp */ 2870 struct icmp *icmp = param.icmp; 2871 struct ip *outer_ip, *inner_ip; 2872 struct udphdr *udp; 2873 struct tcphdr *th, ttemp; 2874 int i_hlen, o_len; 2875 uint16_t port; 2876 2877 outer_ip = (struct ip *)((caddr_t)icmp - sizeof(struct ip)); 2878 inner_ip = &icmp->icmp_ip; 2879 i_hlen = inner_ip->ip_hl << 2; 2880 o_len = ntohs(outer_ip->ip_len); 2881 if (o_len < 2882 (sizeof(struct ip) + 8 + i_hlen + sizeof(struct udphdr) + offsetof(struct tcphdr, th_ack))) { 2883 /* Not enough data present */ 2884 return; 2885 } 2886 /* Ok lets strip out the inner udphdr header by copying up on top of it the tcp hdr */ 2887 udp = (struct udphdr *)(((caddr_t)inner_ip) + i_hlen); 2888 if (ntohs(udp->uh_sport) != V_tcp_udp_tunneling_port) { 2889 return; 2890 } 2891 port = udp->uh_dport; 2892 th = (struct tcphdr *)(udp + 1); 2893 memcpy(&ttemp, th, sizeof(struct tcphdr)); 2894 memcpy(udp, &ttemp, sizeof(struct tcphdr)); 2895 /* Now adjust down the size of the outer IP header */ 2896 o_len -= sizeof(struct udphdr); 2897 outer_ip->ip_len = htons(o_len); 2898 /* Now call in to the normal handling code */ 2899 tcp_ctlinput_with_port(icmp, port); 2900 } 2901 #endif /* INET */ 2902 2903 #ifdef INET6 2904 static inline int 2905 tcp6_next_pmtu(const struct icmp6_hdr *icmp6) 2906 { 2907 int mtu = ntohl(icmp6->icmp6_mtu); 2908 2909 /* 2910 * If no alternative MTU was proposed, or the proposed MTU was too 2911 * small, set to the min. 2912 */ 2913 if (mtu < IPV6_MMTU) 2914 mtu = IPV6_MMTU - 8; /* XXXNP: what is the adjustment for? */ 2915 return (mtu); 2916 } 2917 2918 static void 2919 tcp6_ctlinput_with_port(struct ip6ctlparam *ip6cp, uint16_t port) 2920 { 2921 struct in6_addr *dst; 2922 struct inpcb *(*notify)(struct inpcb *, int); 2923 struct ip6_hdr *ip6; 2924 struct mbuf *m; 2925 struct inpcb *inp; 2926 struct tcpcb *tp; 2927 struct icmp6_hdr *icmp6; 2928 struct in_conninfo inc; 2929 struct tcp_ports { 2930 uint16_t th_sport; 2931 uint16_t th_dport; 2932 } t_ports; 2933 tcp_seq icmp_tcp_seq; 2934 unsigned int mtu; 2935 unsigned int off; 2936 int errno; 2937 2938 icmp6 = ip6cp->ip6c_icmp6; 2939 m = ip6cp->ip6c_m; 2940 ip6 = ip6cp->ip6c_ip6; 2941 off = ip6cp->ip6c_off; 2942 dst = &ip6cp->ip6c_finaldst->sin6_addr; 2943 2944 errno = icmp6_errmap(icmp6); 2945 switch (errno) { 2946 case 0: 2947 return; 2948 case EMSGSIZE: 2949 notify = tcp_mtudisc_notify; 2950 break; 2951 case ECONNREFUSED: 2952 if (V_icmp_may_rst) 2953 notify = tcp_drop_syn_sent; 2954 else 2955 notify = tcp_notify; 2956 break; 2957 case EHOSTUNREACH: 2958 /* 2959 * There are only four ICMPs that may reset connection: 2960 * - administratively prohibited 2961 * - port unreachable 2962 * - time exceeded in transit 2963 * - unknown next header 2964 */ 2965 if (V_icmp_may_rst && 2966 ((icmp6->icmp6_type == ICMP6_DST_UNREACH && 2967 (icmp6->icmp6_code == ICMP6_DST_UNREACH_ADMIN || 2968 icmp6->icmp6_code == ICMP6_DST_UNREACH_NOPORT)) || 2969 (icmp6->icmp6_type == ICMP6_TIME_EXCEEDED && 2970 icmp6->icmp6_code == ICMP6_TIME_EXCEED_TRANSIT) || 2971 (icmp6->icmp6_type == ICMP6_PARAM_PROB && 2972 icmp6->icmp6_code == ICMP6_PARAMPROB_NEXTHEADER))) 2973 notify = tcp_drop_syn_sent; 2974 else 2975 notify = tcp_notify; 2976 break; 2977 default: 2978 notify = tcp_notify; 2979 } 2980 2981 /* Check if we can safely get the ports from the tcp hdr */ 2982 if (m == NULL || 2983 (m->m_pkthdr.len < 2984 (int32_t) (off + sizeof(struct tcp_ports)))) { 2985 return; 2986 } 2987 bzero(&t_ports, sizeof(struct tcp_ports)); 2988 m_copydata(m, off, sizeof(struct tcp_ports), (caddr_t)&t_ports); 2989 inp = in6_pcblookup(&V_tcbinfo, &ip6->ip6_dst, t_ports.th_dport, 2990 &ip6->ip6_src, t_ports.th_sport, INPLOOKUP_WLOCKPCB, NULL); 2991 off += sizeof(struct tcp_ports); 2992 if (m->m_pkthdr.len < (int32_t) (off + sizeof(tcp_seq))) { 2993 goto out; 2994 } 2995 m_copydata(m, off, sizeof(tcp_seq), (caddr_t)&icmp_tcp_seq); 2996 if (inp != NULL) { 2997 tp = intotcpcb(inp); 2998 #ifdef TCP_OFFLOAD 2999 if (tp->t_flags & TF_TOE && errno == EMSGSIZE) { 3000 /* MTU discovery for offloaded connections. */ 3001 mtu = tcp6_next_pmtu(icmp6); 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 if (SEQ_GEQ(ntohl(icmp_tcp_seq), tp->snd_una) && 3009 SEQ_LT(ntohl(icmp_tcp_seq), tp->snd_max)) { 3010 if (errno == EMSGSIZE) { 3011 /* 3012 * MTU discovery: 3013 * If we got a needfrag set the MTU 3014 * in the route to the suggested new 3015 * value (if given) and then notify. 3016 */ 3017 mtu = tcp6_next_pmtu(icmp6); 3018 3019 bzero(&inc, sizeof(inc)); 3020 inc.inc_fibnum = M_GETFIB(m); 3021 inc.inc_flags |= INC_ISIPV6; 3022 inc.inc6_faddr = *dst; 3023 if (in6_setscope(&inc.inc6_faddr, 3024 m->m_pkthdr.rcvif, NULL)) 3025 goto out; 3026 /* 3027 * Only process the offered MTU if it 3028 * is smaller than the current one. 3029 */ 3030 if (mtu < tp->t_maxseg + 3031 sizeof (struct tcphdr) + 3032 sizeof (struct ip6_hdr)) { 3033 tcp_hc_updatemtu(&inc, mtu); 3034 tcp_mtudisc(inp, mtu); 3035 ICMP6STAT_INC(icp6s_pmtuchg); 3036 } 3037 } else 3038 inp = (*notify)(inp, errno); 3039 } 3040 } else { 3041 bzero(&inc, sizeof(inc)); 3042 inc.inc_fibnum = M_GETFIB(m); 3043 inc.inc_flags |= INC_ISIPV6; 3044 inc.inc_fport = t_ports.th_dport; 3045 inc.inc_lport = t_ports.th_sport; 3046 inc.inc6_faddr = *dst; 3047 inc.inc6_laddr = ip6->ip6_src; 3048 syncache_unreach(&inc, icmp_tcp_seq, port); 3049 } 3050 out: 3051 if (inp != NULL) 3052 INP_WUNLOCK(inp); 3053 } 3054 3055 static void 3056 tcp6_ctlinput(struct ip6ctlparam *ctl) 3057 { 3058 tcp6_ctlinput_with_port(ctl, htons(0)); 3059 } 3060 3061 static void 3062 tcp6_ctlinput_viaudp(udp_tun_icmp_param_t param) 3063 { 3064 struct ip6ctlparam *ip6cp = param.ip6cp; 3065 struct mbuf *m; 3066 struct udphdr *udp; 3067 uint16_t port; 3068 3069 m = m_pulldown(ip6cp->ip6c_m, ip6cp->ip6c_off, sizeof(struct udphdr), NULL); 3070 if (m == NULL) { 3071 return; 3072 } 3073 udp = mtod(m, struct udphdr *); 3074 if (ntohs(udp->uh_sport) != V_tcp_udp_tunneling_port) { 3075 return; 3076 } 3077 port = udp->uh_dport; 3078 m_adj(m, sizeof(struct udphdr)); 3079 if ((m->m_flags & M_PKTHDR) == 0) { 3080 ip6cp->ip6c_m->m_pkthdr.len -= sizeof(struct udphdr); 3081 } 3082 /* Now call in to the normal handling code */ 3083 tcp6_ctlinput_with_port(ip6cp, port); 3084 } 3085 3086 #endif /* INET6 */ 3087 3088 static uint32_t 3089 tcp_keyed_hash(struct in_conninfo *inc, u_char *key, u_int len) 3090 { 3091 SIPHASH_CTX ctx; 3092 uint32_t hash[2]; 3093 3094 KASSERT(len >= SIPHASH_KEY_LENGTH, 3095 ("%s: keylen %u too short ", __func__, len)); 3096 SipHash24_Init(&ctx); 3097 SipHash_SetKey(&ctx, (uint8_t *)key); 3098 SipHash_Update(&ctx, &inc->inc_fport, sizeof(uint16_t)); 3099 SipHash_Update(&ctx, &inc->inc_lport, sizeof(uint16_t)); 3100 switch (inc->inc_flags & INC_ISIPV6) { 3101 #ifdef INET 3102 case 0: 3103 SipHash_Update(&ctx, &inc->inc_faddr, sizeof(struct in_addr)); 3104 SipHash_Update(&ctx, &inc->inc_laddr, sizeof(struct in_addr)); 3105 break; 3106 #endif 3107 #ifdef INET6 3108 case INC_ISIPV6: 3109 SipHash_Update(&ctx, &inc->inc6_faddr, sizeof(struct in6_addr)); 3110 SipHash_Update(&ctx, &inc->inc6_laddr, sizeof(struct in6_addr)); 3111 break; 3112 #endif 3113 } 3114 SipHash_Final((uint8_t *)hash, &ctx); 3115 3116 return (hash[0] ^ hash[1]); 3117 } 3118 3119 uint32_t 3120 tcp_new_ts_offset(struct in_conninfo *inc) 3121 { 3122 struct in_conninfo inc_store, *local_inc; 3123 3124 if (!V_tcp_ts_offset_per_conn) { 3125 memcpy(&inc_store, inc, sizeof(struct in_conninfo)); 3126 inc_store.inc_lport = 0; 3127 inc_store.inc_fport = 0; 3128 local_inc = &inc_store; 3129 } else { 3130 local_inc = inc; 3131 } 3132 return (tcp_keyed_hash(local_inc, V_ts_offset_secret, 3133 sizeof(V_ts_offset_secret))); 3134 } 3135 3136 /* 3137 * Following is where TCP initial sequence number generation occurs. 3138 * 3139 * There are two places where we must use initial sequence numbers: 3140 * 1. In SYN-ACK packets. 3141 * 2. In SYN packets. 3142 * 3143 * All ISNs for SYN-ACK packets are generated by the syncache. See 3144 * tcp_syncache.c for details. 3145 * 3146 * The ISNs in SYN packets must be monotonic; TIME_WAIT recycling 3147 * depends on this property. In addition, these ISNs should be 3148 * unguessable so as to prevent connection hijacking. To satisfy 3149 * the requirements of this situation, the algorithm outlined in 3150 * RFC 1948 is used, with only small modifications. 3151 * 3152 * Implementation details: 3153 * 3154 * Time is based off the system timer, and is corrected so that it 3155 * increases by one megabyte per second. This allows for proper 3156 * recycling on high speed LANs while still leaving over an hour 3157 * before rollover. 3158 * 3159 * As reading the *exact* system time is too expensive to be done 3160 * whenever setting up a TCP connection, we increment the time 3161 * offset in two ways. First, a small random positive increment 3162 * is added to isn_offset for each connection that is set up. 3163 * Second, the function tcp_isn_tick fires once per clock tick 3164 * and increments isn_offset as necessary so that sequence numbers 3165 * are incremented at approximately ISN_BYTES_PER_SECOND. The 3166 * random positive increments serve only to ensure that the same 3167 * exact sequence number is never sent out twice (as could otherwise 3168 * happen when a port is recycled in less than the system tick 3169 * interval.) 3170 * 3171 * net.inet.tcp.isn_reseed_interval controls the number of seconds 3172 * between seeding of isn_secret. This is normally set to zero, 3173 * as reseeding should not be necessary. 3174 * 3175 * Locking of the global variables isn_secret, isn_last_reseed, isn_offset, 3176 * isn_offset_old, and isn_ctx is performed using the ISN lock. In 3177 * general, this means holding an exclusive (write) lock. 3178 */ 3179 3180 #define ISN_BYTES_PER_SECOND 1048576 3181 #define ISN_STATIC_INCREMENT 4096 3182 #define ISN_RANDOM_INCREMENT (4096 - 1) 3183 #define ISN_SECRET_LENGTH SIPHASH_KEY_LENGTH 3184 3185 VNET_DEFINE_STATIC(u_char, isn_secret[ISN_SECRET_LENGTH]); 3186 VNET_DEFINE_STATIC(int, isn_last); 3187 VNET_DEFINE_STATIC(int, isn_last_reseed); 3188 VNET_DEFINE_STATIC(u_int32_t, isn_offset); 3189 VNET_DEFINE_STATIC(u_int32_t, isn_offset_old); 3190 3191 #define V_isn_secret VNET(isn_secret) 3192 #define V_isn_last VNET(isn_last) 3193 #define V_isn_last_reseed VNET(isn_last_reseed) 3194 #define V_isn_offset VNET(isn_offset) 3195 #define V_isn_offset_old VNET(isn_offset_old) 3196 3197 tcp_seq 3198 tcp_new_isn(struct in_conninfo *inc) 3199 { 3200 tcp_seq new_isn; 3201 u_int32_t projected_offset; 3202 3203 ISN_LOCK(); 3204 /* Seed if this is the first use, reseed if requested. */ 3205 if ((V_isn_last_reseed == 0) || ((V_tcp_isn_reseed_interval > 0) && 3206 (((u_int)V_isn_last_reseed + (u_int)V_tcp_isn_reseed_interval*hz) 3207 < (u_int)ticks))) { 3208 arc4rand(&V_isn_secret, sizeof(V_isn_secret), 0); 3209 V_isn_last_reseed = ticks; 3210 } 3211 3212 /* Compute the hash and return the ISN. */ 3213 new_isn = (tcp_seq)tcp_keyed_hash(inc, V_isn_secret, 3214 sizeof(V_isn_secret)); 3215 V_isn_offset += ISN_STATIC_INCREMENT + 3216 (arc4random() & ISN_RANDOM_INCREMENT); 3217 if (ticks != V_isn_last) { 3218 projected_offset = V_isn_offset_old + 3219 ISN_BYTES_PER_SECOND / hz * (ticks - V_isn_last); 3220 if (SEQ_GT(projected_offset, V_isn_offset)) 3221 V_isn_offset = projected_offset; 3222 V_isn_offset_old = V_isn_offset; 3223 V_isn_last = ticks; 3224 } 3225 new_isn += V_isn_offset; 3226 ISN_UNLOCK(); 3227 return (new_isn); 3228 } 3229 3230 /* 3231 * When a specific ICMP unreachable message is received and the 3232 * connection state is SYN-SENT, drop the connection. This behavior 3233 * is controlled by the icmp_may_rst sysctl. 3234 */ 3235 static struct inpcb * 3236 tcp_drop_syn_sent(struct inpcb *inp, int errno) 3237 { 3238 struct tcpcb *tp; 3239 3240 NET_EPOCH_ASSERT(); 3241 INP_WLOCK_ASSERT(inp); 3242 3243 tp = intotcpcb(inp); 3244 if (tp->t_state != TCPS_SYN_SENT) 3245 return (inp); 3246 3247 if (IS_FASTOPEN(tp->t_flags)) 3248 tcp_fastopen_disable_path(tp); 3249 3250 tp = tcp_drop(tp, errno); 3251 if (tp != NULL) 3252 return (inp); 3253 else 3254 return (NULL); 3255 } 3256 3257 /* 3258 * When `need fragmentation' ICMP is received, update our idea of the MSS 3259 * based on the new value. Also nudge TCP to send something, since we 3260 * know the packet we just sent was dropped. 3261 * This duplicates some code in the tcp_mss() function in tcp_input.c. 3262 */ 3263 static struct inpcb * 3264 tcp_mtudisc_notify(struct inpcb *inp, int error) 3265 { 3266 3267 return (tcp_mtudisc(inp, -1)); 3268 } 3269 3270 static struct inpcb * 3271 tcp_mtudisc(struct inpcb *inp, int mtuoffer) 3272 { 3273 struct tcpcb *tp; 3274 struct socket *so; 3275 3276 INP_WLOCK_ASSERT(inp); 3277 3278 tp = intotcpcb(inp); 3279 KASSERT(tp != NULL, ("tcp_mtudisc: tp == NULL")); 3280 3281 tcp_mss_update(tp, -1, mtuoffer, NULL, NULL); 3282 3283 so = inp->inp_socket; 3284 SOCKBUF_LOCK(&so->so_snd); 3285 /* If the mss is larger than the socket buffer, decrease the mss. */ 3286 if (so->so_snd.sb_hiwat < tp->t_maxseg) 3287 tp->t_maxseg = so->so_snd.sb_hiwat; 3288 SOCKBUF_UNLOCK(&so->so_snd); 3289 3290 TCPSTAT_INC(tcps_mturesent); 3291 tp->t_rtttime = 0; 3292 tp->snd_nxt = tp->snd_una; 3293 tcp_free_sackholes(tp); 3294 tp->snd_recover = tp->snd_max; 3295 if (tp->t_flags & TF_SACK_PERMIT) 3296 EXIT_FASTRECOVERY(tp->t_flags); 3297 if (tp->t_fb->tfb_tcp_mtu_chg != NULL) { 3298 /* 3299 * Conceptually the snd_nxt setting 3300 * and freeing sack holes should 3301 * be done by the default stacks 3302 * own tfb_tcp_mtu_chg(). 3303 */ 3304 tp->t_fb->tfb_tcp_mtu_chg(tp); 3305 } 3306 if (tcp_output(tp) < 0) 3307 return (NULL); 3308 else 3309 return (inp); 3310 } 3311 3312 #ifdef INET 3313 /* 3314 * Look-up the routing entry to the peer of this inpcb. If no route 3315 * is found and it cannot be allocated, then return 0. This routine 3316 * is called by TCP routines that access the rmx structure and by 3317 * tcp_mss_update to get the peer/interface MTU. 3318 */ 3319 uint32_t 3320 tcp_maxmtu(struct in_conninfo *inc, struct tcp_ifcap *cap) 3321 { 3322 struct nhop_object *nh; 3323 struct ifnet *ifp; 3324 uint32_t maxmtu = 0; 3325 3326 KASSERT(inc != NULL, ("tcp_maxmtu with NULL in_conninfo pointer")); 3327 3328 if (inc->inc_faddr.s_addr != INADDR_ANY) { 3329 nh = fib4_lookup(inc->inc_fibnum, inc->inc_faddr, 0, NHR_NONE, 0); 3330 if (nh == NULL) 3331 return (0); 3332 3333 ifp = nh->nh_ifp; 3334 maxmtu = nh->nh_mtu; 3335 3336 /* Report additional interface capabilities. */ 3337 if (cap != NULL) { 3338 if (ifp->if_capenable & IFCAP_TSO4 && 3339 ifp->if_hwassist & CSUM_TSO) { 3340 cap->ifcap |= CSUM_TSO; 3341 cap->tsomax = ifp->if_hw_tsomax; 3342 cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount; 3343 cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize; 3344 } 3345 } 3346 } 3347 return (maxmtu); 3348 } 3349 #endif /* INET */ 3350 3351 #ifdef INET6 3352 uint32_t 3353 tcp_maxmtu6(struct in_conninfo *inc, struct tcp_ifcap *cap) 3354 { 3355 struct nhop_object *nh; 3356 struct in6_addr dst6; 3357 uint32_t scopeid; 3358 struct ifnet *ifp; 3359 uint32_t maxmtu = 0; 3360 3361 KASSERT(inc != NULL, ("tcp_maxmtu6 with NULL in_conninfo pointer")); 3362 3363 if (inc->inc_flags & INC_IPV6MINMTU) 3364 return (IPV6_MMTU); 3365 3366 if (!IN6_IS_ADDR_UNSPECIFIED(&inc->inc6_faddr)) { 3367 in6_splitscope(&inc->inc6_faddr, &dst6, &scopeid); 3368 nh = fib6_lookup(inc->inc_fibnum, &dst6, scopeid, NHR_NONE, 0); 3369 if (nh == NULL) 3370 return (0); 3371 3372 ifp = nh->nh_ifp; 3373 maxmtu = nh->nh_mtu; 3374 3375 /* Report additional interface capabilities. */ 3376 if (cap != NULL) { 3377 if (ifp->if_capenable & IFCAP_TSO6 && 3378 ifp->if_hwassist & CSUM_TSO) { 3379 cap->ifcap |= CSUM_TSO; 3380 cap->tsomax = ifp->if_hw_tsomax; 3381 cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount; 3382 cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize; 3383 } 3384 } 3385 } 3386 3387 return (maxmtu); 3388 } 3389 3390 /* 3391 * Handle setsockopt(IPV6_USE_MIN_MTU) by a TCP stack. 3392 * 3393 * XXXGL: we are updating inpcb here with INC_IPV6MINMTU flag. 3394 * The right place to do that is ip6_setpktopt() that has just been 3395 * executed. By the way it just filled ip6po_minmtu for us. 3396 */ 3397 void 3398 tcp6_use_min_mtu(struct tcpcb *tp) 3399 { 3400 struct inpcb *inp = tptoinpcb(tp); 3401 3402 INP_WLOCK_ASSERT(inp); 3403 /* 3404 * In case of the IPV6_USE_MIN_MTU socket 3405 * option, the INC_IPV6MINMTU flag to announce 3406 * a corresponding MSS during the initial 3407 * handshake. If the TCP connection is not in 3408 * the front states, just reduce the MSS being 3409 * used. This avoids the sending of TCP 3410 * segments which will be fragmented at the 3411 * IPv6 layer. 3412 */ 3413 inp->inp_inc.inc_flags |= INC_IPV6MINMTU; 3414 if ((tp->t_state >= TCPS_SYN_SENT) && 3415 (inp->inp_inc.inc_flags & INC_ISIPV6)) { 3416 struct ip6_pktopts *opt; 3417 3418 opt = inp->in6p_outputopts; 3419 if (opt != NULL && opt->ip6po_minmtu == IP6PO_MINMTU_ALL && 3420 tp->t_maxseg > TCP6_MSS) 3421 tp->t_maxseg = TCP6_MSS; 3422 } 3423 } 3424 #endif /* INET6 */ 3425 3426 /* 3427 * Calculate effective SMSS per RFC5681 definition for a given TCP 3428 * connection at its current state, taking into account SACK and etc. 3429 */ 3430 u_int 3431 tcp_maxseg(const struct tcpcb *tp) 3432 { 3433 u_int optlen; 3434 3435 if (tp->t_flags & TF_NOOPT) 3436 return (tp->t_maxseg); 3437 3438 /* 3439 * Here we have a simplified code from tcp_addoptions(), 3440 * without a proper loop, and having most of paddings hardcoded. 3441 * We might make mistakes with padding here in some edge cases, 3442 * but this is harmless, since result of tcp_maxseg() is used 3443 * only in cwnd and ssthresh estimations. 3444 */ 3445 if (TCPS_HAVEESTABLISHED(tp->t_state)) { 3446 if (tp->t_flags & TF_RCVD_TSTMP) 3447 optlen = TCPOLEN_TSTAMP_APPA; 3448 else 3449 optlen = 0; 3450 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3451 if (tp->t_flags & TF_SIGNATURE) 3452 optlen += PADTCPOLEN(TCPOLEN_SIGNATURE); 3453 #endif 3454 if ((tp->t_flags & TF_SACK_PERMIT) && tp->rcv_numsacks > 0) { 3455 optlen += TCPOLEN_SACKHDR; 3456 optlen += tp->rcv_numsacks * TCPOLEN_SACK; 3457 optlen = PADTCPOLEN(optlen); 3458 } 3459 } else { 3460 if (tp->t_flags & TF_REQ_TSTMP) 3461 optlen = TCPOLEN_TSTAMP_APPA; 3462 else 3463 optlen = PADTCPOLEN(TCPOLEN_MAXSEG); 3464 if (tp->t_flags & TF_REQ_SCALE) 3465 optlen += PADTCPOLEN(TCPOLEN_WINDOW); 3466 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3467 if (tp->t_flags & TF_SIGNATURE) 3468 optlen += PADTCPOLEN(TCPOLEN_SIGNATURE); 3469 #endif 3470 if (tp->t_flags & TF_SACK_PERMIT) 3471 optlen += PADTCPOLEN(TCPOLEN_SACK_PERMITTED); 3472 } 3473 #undef PAD 3474 optlen = min(optlen, TCP_MAXOLEN); 3475 return (tp->t_maxseg - optlen); 3476 } 3477 3478 3479 u_int 3480 tcp_fixed_maxseg(const struct tcpcb *tp) 3481 { 3482 int optlen; 3483 3484 if (tp->t_flags & TF_NOOPT) 3485 return (tp->t_maxseg); 3486 3487 /* 3488 * Here we have a simplified code from tcp_addoptions(), 3489 * without a proper loop, and having most of paddings hardcoded. 3490 * We only consider fixed options that we would send every 3491 * time I.e. SACK is not considered. This is important 3492 * for cc modules to figure out what the modulo of the 3493 * cwnd should be. 3494 */ 3495 #define PAD(len) ((((len) / 4) + !!((len) % 4)) * 4) 3496 if (TCPS_HAVEESTABLISHED(tp->t_state)) { 3497 if (tp->t_flags & TF_RCVD_TSTMP) 3498 optlen = TCPOLEN_TSTAMP_APPA; 3499 else 3500 optlen = 0; 3501 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3502 if (tp->t_flags & TF_SIGNATURE) 3503 optlen += PAD(TCPOLEN_SIGNATURE); 3504 #endif 3505 } else { 3506 if (tp->t_flags & TF_REQ_TSTMP) 3507 optlen = TCPOLEN_TSTAMP_APPA; 3508 else 3509 optlen = PAD(TCPOLEN_MAXSEG); 3510 if (tp->t_flags & TF_REQ_SCALE) 3511 optlen += PAD(TCPOLEN_WINDOW); 3512 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3513 if (tp->t_flags & TF_SIGNATURE) 3514 optlen += PAD(TCPOLEN_SIGNATURE); 3515 #endif 3516 if (tp->t_flags & TF_SACK_PERMIT) 3517 optlen += PAD(TCPOLEN_SACK_PERMITTED); 3518 } 3519 #undef PAD 3520 optlen = min(optlen, TCP_MAXOLEN); 3521 return (tp->t_maxseg - optlen); 3522 } 3523 3524 3525 3526 static int 3527 sysctl_drop(SYSCTL_HANDLER_ARGS) 3528 { 3529 /* addrs[0] is a foreign socket, addrs[1] is a local one. */ 3530 struct sockaddr_storage addrs[2]; 3531 struct inpcb *inp; 3532 struct tcpcb *tp; 3533 #ifdef INET 3534 struct sockaddr_in *fin = NULL, *lin = NULL; 3535 #endif 3536 struct epoch_tracker et; 3537 #ifdef INET6 3538 struct sockaddr_in6 *fin6, *lin6; 3539 #endif 3540 int error; 3541 3542 inp = NULL; 3543 #ifdef INET6 3544 fin6 = lin6 = NULL; 3545 #endif 3546 error = 0; 3547 3548 if (req->oldptr != NULL || req->oldlen != 0) 3549 return (EINVAL); 3550 if (req->newptr == NULL) 3551 return (EPERM); 3552 if (req->newlen < sizeof(addrs)) 3553 return (ENOMEM); 3554 error = SYSCTL_IN(req, &addrs, sizeof(addrs)); 3555 if (error) 3556 return (error); 3557 3558 switch (addrs[0].ss_family) { 3559 #ifdef INET6 3560 case AF_INET6: 3561 fin6 = (struct sockaddr_in6 *)&addrs[0]; 3562 lin6 = (struct sockaddr_in6 *)&addrs[1]; 3563 if (fin6->sin6_len != sizeof(struct sockaddr_in6) || 3564 lin6->sin6_len != sizeof(struct sockaddr_in6)) 3565 return (EINVAL); 3566 if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr)) { 3567 if (!IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr)) 3568 return (EINVAL); 3569 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[0]); 3570 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[1]); 3571 #ifdef INET 3572 fin = (struct sockaddr_in *)&addrs[0]; 3573 lin = (struct sockaddr_in *)&addrs[1]; 3574 #endif 3575 break; 3576 } 3577 error = sa6_embedscope(fin6, V_ip6_use_defzone); 3578 if (error) 3579 return (error); 3580 error = sa6_embedscope(lin6, V_ip6_use_defzone); 3581 if (error) 3582 return (error); 3583 break; 3584 #endif 3585 #ifdef INET 3586 case AF_INET: 3587 fin = (struct sockaddr_in *)&addrs[0]; 3588 lin = (struct sockaddr_in *)&addrs[1]; 3589 if (fin->sin_len != sizeof(struct sockaddr_in) || 3590 lin->sin_len != sizeof(struct sockaddr_in)) 3591 return (EINVAL); 3592 break; 3593 #endif 3594 default: 3595 return (EINVAL); 3596 } 3597 NET_EPOCH_ENTER(et); 3598 switch (addrs[0].ss_family) { 3599 #ifdef INET6 3600 case AF_INET6: 3601 inp = in6_pcblookup(&V_tcbinfo, &fin6->sin6_addr, 3602 fin6->sin6_port, &lin6->sin6_addr, lin6->sin6_port, 3603 INPLOOKUP_WLOCKPCB, NULL); 3604 break; 3605 #endif 3606 #ifdef INET 3607 case AF_INET: 3608 inp = in_pcblookup(&V_tcbinfo, fin->sin_addr, fin->sin_port, 3609 lin->sin_addr, lin->sin_port, INPLOOKUP_WLOCKPCB, NULL); 3610 break; 3611 #endif 3612 } 3613 if (inp != NULL) { 3614 if (!SOLISTENING(inp->inp_socket)) { 3615 tp = intotcpcb(inp); 3616 tp = tcp_drop(tp, ECONNABORTED); 3617 if (tp != NULL) 3618 INP_WUNLOCK(inp); 3619 } else 3620 INP_WUNLOCK(inp); 3621 } else 3622 error = ESRCH; 3623 NET_EPOCH_EXIT(et); 3624 return (error); 3625 } 3626 3627 SYSCTL_PROC(_net_inet_tcp, TCPCTL_DROP, drop, 3628 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | 3629 CTLFLAG_NEEDGIANT, NULL, 0, sysctl_drop, "", 3630 "Drop TCP connection"); 3631 3632 static int 3633 tcp_sysctl_setsockopt(SYSCTL_HANDLER_ARGS) 3634 { 3635 return (sysctl_setsockopt(oidp, arg1, arg2, req, &V_tcbinfo, 3636 &tcp_ctloutput_set)); 3637 } 3638 3639 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, setsockopt, 3640 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | 3641 CTLFLAG_MPSAFE, NULL, 0, tcp_sysctl_setsockopt, "", 3642 "Set socket option for TCP endpoint"); 3643 3644 #ifdef KERN_TLS 3645 static int 3646 sysctl_switch_tls(SYSCTL_HANDLER_ARGS) 3647 { 3648 /* addrs[0] is a foreign socket, addrs[1] is a local one. */ 3649 struct sockaddr_storage addrs[2]; 3650 struct inpcb *inp; 3651 #ifdef INET 3652 struct sockaddr_in *fin = NULL, *lin = NULL; 3653 #endif 3654 struct epoch_tracker et; 3655 #ifdef INET6 3656 struct sockaddr_in6 *fin6, *lin6; 3657 #endif 3658 int error; 3659 3660 inp = NULL; 3661 #ifdef INET6 3662 fin6 = lin6 = NULL; 3663 #endif 3664 error = 0; 3665 3666 if (req->oldptr != NULL || req->oldlen != 0) 3667 return (EINVAL); 3668 if (req->newptr == NULL) 3669 return (EPERM); 3670 if (req->newlen < sizeof(addrs)) 3671 return (ENOMEM); 3672 error = SYSCTL_IN(req, &addrs, sizeof(addrs)); 3673 if (error) 3674 return (error); 3675 3676 switch (addrs[0].ss_family) { 3677 #ifdef INET6 3678 case AF_INET6: 3679 fin6 = (struct sockaddr_in6 *)&addrs[0]; 3680 lin6 = (struct sockaddr_in6 *)&addrs[1]; 3681 if (fin6->sin6_len != sizeof(struct sockaddr_in6) || 3682 lin6->sin6_len != sizeof(struct sockaddr_in6)) 3683 return (EINVAL); 3684 if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr)) { 3685 if (!IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr)) 3686 return (EINVAL); 3687 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[0]); 3688 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[1]); 3689 #ifdef INET 3690 fin = (struct sockaddr_in *)&addrs[0]; 3691 lin = (struct sockaddr_in *)&addrs[1]; 3692 #endif 3693 break; 3694 } 3695 error = sa6_embedscope(fin6, V_ip6_use_defzone); 3696 if (error) 3697 return (error); 3698 error = sa6_embedscope(lin6, V_ip6_use_defzone); 3699 if (error) 3700 return (error); 3701 break; 3702 #endif 3703 #ifdef INET 3704 case AF_INET: 3705 fin = (struct sockaddr_in *)&addrs[0]; 3706 lin = (struct sockaddr_in *)&addrs[1]; 3707 if (fin->sin_len != sizeof(struct sockaddr_in) || 3708 lin->sin_len != sizeof(struct sockaddr_in)) 3709 return (EINVAL); 3710 break; 3711 #endif 3712 default: 3713 return (EINVAL); 3714 } 3715 NET_EPOCH_ENTER(et); 3716 switch (addrs[0].ss_family) { 3717 #ifdef INET6 3718 case AF_INET6: 3719 inp = in6_pcblookup(&V_tcbinfo, &fin6->sin6_addr, 3720 fin6->sin6_port, &lin6->sin6_addr, lin6->sin6_port, 3721 INPLOOKUP_WLOCKPCB, NULL); 3722 break; 3723 #endif 3724 #ifdef INET 3725 case AF_INET: 3726 inp = in_pcblookup(&V_tcbinfo, fin->sin_addr, fin->sin_port, 3727 lin->sin_addr, lin->sin_port, INPLOOKUP_WLOCKPCB, NULL); 3728 break; 3729 #endif 3730 } 3731 NET_EPOCH_EXIT(et); 3732 if (inp != NULL) { 3733 struct socket *so; 3734 3735 so = inp->inp_socket; 3736 soref(so); 3737 error = ktls_set_tx_mode(so, 3738 arg2 == 0 ? TCP_TLS_MODE_SW : TCP_TLS_MODE_IFNET); 3739 INP_WUNLOCK(inp); 3740 sorele(so); 3741 } else 3742 error = ESRCH; 3743 return (error); 3744 } 3745 3746 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, switch_to_sw_tls, 3747 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | 3748 CTLFLAG_NEEDGIANT, NULL, 0, sysctl_switch_tls, "", 3749 "Switch TCP connection to SW TLS"); 3750 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, switch_to_ifnet_tls, 3751 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | 3752 CTLFLAG_NEEDGIANT, NULL, 1, sysctl_switch_tls, "", 3753 "Switch TCP connection to ifnet TLS"); 3754 #endif 3755 3756 /* 3757 * Generate a standardized TCP log line for use throughout the 3758 * tcp subsystem. Memory allocation is done with M_NOWAIT to 3759 * allow use in the interrupt context. 3760 * 3761 * NB: The caller MUST free(s, M_TCPLOG) the returned string. 3762 * NB: The function may return NULL if memory allocation failed. 3763 * 3764 * Due to header inclusion and ordering limitations the struct ip 3765 * and ip6_hdr pointers have to be passed as void pointers. 3766 */ 3767 char * 3768 tcp_log_vain(struct in_conninfo *inc, struct tcphdr *th, const void *ip4hdr, 3769 const void *ip6hdr) 3770 { 3771 3772 /* Is logging enabled? */ 3773 if (V_tcp_log_in_vain == 0) 3774 return (NULL); 3775 3776 return (tcp_log_addr(inc, th, ip4hdr, ip6hdr)); 3777 } 3778 3779 char * 3780 tcp_log_addrs(struct in_conninfo *inc, struct tcphdr *th, const void *ip4hdr, 3781 const void *ip6hdr) 3782 { 3783 3784 /* Is logging enabled? */ 3785 if (tcp_log_debug == 0) 3786 return (NULL); 3787 3788 return (tcp_log_addr(inc, th, ip4hdr, ip6hdr)); 3789 } 3790 3791 static char * 3792 tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th, const void *ip4hdr, 3793 const void *ip6hdr) 3794 { 3795 char *s, *sp; 3796 size_t size; 3797 #ifdef INET 3798 const struct ip *ip = (const struct ip *)ip4hdr; 3799 #endif 3800 #ifdef INET6 3801 const struct ip6_hdr *ip6 = (const struct ip6_hdr *)ip6hdr; 3802 #endif /* INET6 */ 3803 3804 /* 3805 * The log line looks like this: 3806 * "TCP: [1.2.3.4]:50332 to [1.2.3.4]:80 tcpflags 0x2<SYN>" 3807 */ 3808 size = sizeof("TCP: []:12345 to []:12345 tcpflags 0x2<>") + 3809 sizeof(PRINT_TH_FLAGS) + 1 + 3810 #ifdef INET6 3811 2 * INET6_ADDRSTRLEN; 3812 #else 3813 2 * INET_ADDRSTRLEN; 3814 #endif /* INET6 */ 3815 3816 s = malloc(size, M_TCPLOG, M_ZERO|M_NOWAIT); 3817 if (s == NULL) 3818 return (NULL); 3819 3820 strcat(s, "TCP: ["); 3821 sp = s + strlen(s); 3822 3823 if (inc && ((inc->inc_flags & INC_ISIPV6) == 0)) { 3824 inet_ntoa_r(inc->inc_faddr, sp); 3825 sp = s + strlen(s); 3826 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport)); 3827 sp = s + strlen(s); 3828 inet_ntoa_r(inc->inc_laddr, sp); 3829 sp = s + strlen(s); 3830 sprintf(sp, "]:%i", ntohs(inc->inc_lport)); 3831 #ifdef INET6 3832 } else if (inc) { 3833 ip6_sprintf(sp, &inc->inc6_faddr); 3834 sp = s + strlen(s); 3835 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport)); 3836 sp = s + strlen(s); 3837 ip6_sprintf(sp, &inc->inc6_laddr); 3838 sp = s + strlen(s); 3839 sprintf(sp, "]:%i", ntohs(inc->inc_lport)); 3840 } else if (ip6 && th) { 3841 ip6_sprintf(sp, &ip6->ip6_src); 3842 sp = s + strlen(s); 3843 sprintf(sp, "]:%i to [", ntohs(th->th_sport)); 3844 sp = s + strlen(s); 3845 ip6_sprintf(sp, &ip6->ip6_dst); 3846 sp = s + strlen(s); 3847 sprintf(sp, "]:%i", ntohs(th->th_dport)); 3848 #endif /* INET6 */ 3849 #ifdef INET 3850 } else if (ip && th) { 3851 inet_ntoa_r(ip->ip_src, sp); 3852 sp = s + strlen(s); 3853 sprintf(sp, "]:%i to [", ntohs(th->th_sport)); 3854 sp = s + strlen(s); 3855 inet_ntoa_r(ip->ip_dst, sp); 3856 sp = s + strlen(s); 3857 sprintf(sp, "]:%i", ntohs(th->th_dport)); 3858 #endif /* INET */ 3859 } else { 3860 free(s, M_TCPLOG); 3861 return (NULL); 3862 } 3863 sp = s + strlen(s); 3864 if (th) 3865 sprintf(sp, " tcpflags 0x%b", tcp_get_flags(th), PRINT_TH_FLAGS); 3866 if (*(s + size - 1) != '\0') 3867 panic("%s: string too long", __func__); 3868 return (s); 3869 } 3870 3871 /* 3872 * A subroutine which makes it easy to track TCP state changes with DTrace. 3873 * This function shouldn't be called for t_state initializations that don't 3874 * correspond to actual TCP state transitions. 3875 */ 3876 void 3877 tcp_state_change(struct tcpcb *tp, int newstate) 3878 { 3879 #if defined(KDTRACE_HOOKS) 3880 int pstate = tp->t_state; 3881 #endif 3882 3883 TCPSTATES_DEC(tp->t_state); 3884 TCPSTATES_INC(newstate); 3885 tp->t_state = newstate; 3886 TCP_PROBE6(state__change, NULL, tp, NULL, tp, NULL, pstate); 3887 } 3888 3889 /* 3890 * Create an external-format (``xtcpcb'') structure using the information in 3891 * the kernel-format tcpcb structure pointed to by tp. This is done to 3892 * reduce the spew of irrelevant information over this interface, to isolate 3893 * user code from changes in the kernel structure, and potentially to provide 3894 * information-hiding if we decide that some of this information should be 3895 * hidden from users. 3896 */ 3897 void 3898 tcp_inptoxtp(const struct inpcb *inp, struct xtcpcb *xt) 3899 { 3900 struct tcpcb *tp = intotcpcb(inp); 3901 sbintime_t now; 3902 3903 bzero(xt, sizeof(*xt)); 3904 xt->t_state = tp->t_state; 3905 xt->t_logstate = tcp_get_bblog_state(tp); 3906 xt->t_flags = tp->t_flags; 3907 xt->t_sndzerowin = tp->t_sndzerowin; 3908 xt->t_sndrexmitpack = tp->t_sndrexmitpack; 3909 xt->t_rcvoopack = tp->t_rcvoopack; 3910 xt->t_rcv_wnd = tp->rcv_wnd; 3911 xt->t_snd_wnd = tp->snd_wnd; 3912 xt->t_snd_cwnd = tp->snd_cwnd; 3913 xt->t_snd_ssthresh = tp->snd_ssthresh; 3914 xt->t_dsack_bytes = tp->t_dsack_bytes; 3915 xt->t_dsack_tlp_bytes = tp->t_dsack_tlp_bytes; 3916 xt->t_dsack_pack = tp->t_dsack_pack; 3917 xt->t_maxseg = tp->t_maxseg; 3918 xt->xt_ecn = (tp->t_flags2 & TF2_ECN_PERMIT) ? 1 : 0 + 3919 (tp->t_flags2 & TF2_ACE_PERMIT) ? 2 : 0; 3920 3921 now = getsbinuptime(); 3922 #define COPYTIMER(which,where) do { \ 3923 if (tp->t_timers[which] != SBT_MAX) \ 3924 xt->where = (tp->t_timers[which] - now) / SBT_1MS; \ 3925 else \ 3926 xt->where = 0; \ 3927 } while (0) 3928 COPYTIMER(TT_DELACK, tt_delack); 3929 COPYTIMER(TT_REXMT, tt_rexmt); 3930 COPYTIMER(TT_PERSIST, tt_persist); 3931 COPYTIMER(TT_KEEP, tt_keep); 3932 COPYTIMER(TT_2MSL, tt_2msl); 3933 #undef COPYTIMER 3934 xt->t_rcvtime = 1000 * (ticks - tp->t_rcvtime) / hz; 3935 3936 xt->xt_encaps_port = tp->t_port; 3937 bcopy(tp->t_fb->tfb_tcp_block_name, xt->xt_stack, 3938 TCP_FUNCTION_NAME_LEN_MAX); 3939 bcopy(CC_ALGO(tp)->name, xt->xt_cc, TCP_CA_NAME_MAX); 3940 #ifdef TCP_BLACKBOX 3941 (void)tcp_log_get_id(tp, xt->xt_logid); 3942 #endif 3943 3944 xt->xt_len = sizeof(struct xtcpcb); 3945 in_pcbtoxinpcb(inp, &xt->xt_inp); 3946 } 3947 3948 void 3949 tcp_log_end_status(struct tcpcb *tp, uint8_t status) 3950 { 3951 uint32_t bit, i; 3952 3953 if ((tp == NULL) || 3954 (status > TCP_EI_STATUS_MAX_VALUE) || 3955 (status == 0)) { 3956 /* Invalid */ 3957 return; 3958 } 3959 if (status > (sizeof(uint32_t) * 8)) { 3960 /* Should this be a KASSERT? */ 3961 return; 3962 } 3963 bit = 1U << (status - 1); 3964 if (bit & tp->t_end_info_status) { 3965 /* already logged */ 3966 return; 3967 } 3968 for (i = 0; i < TCP_END_BYTE_INFO; i++) { 3969 if (tp->t_end_info_bytes[i] == TCP_EI_EMPTY_SLOT) { 3970 tp->t_end_info_bytes[i] = status; 3971 tp->t_end_info_status |= bit; 3972 break; 3973 } 3974 } 3975 } 3976 3977 int 3978 tcp_can_enable_pacing(void) 3979 { 3980 3981 if ((tcp_pacing_limit == -1) || 3982 (tcp_pacing_limit > number_of_tcp_connections_pacing)) { 3983 atomic_fetchadd_int(&number_of_tcp_connections_pacing, 1); 3984 shadow_num_connections = number_of_tcp_connections_pacing; 3985 return (1); 3986 } else { 3987 return (0); 3988 } 3989 } 3990 3991 static uint8_t tcp_pacing_warning = 0; 3992 3993 void 3994 tcp_decrement_paced_conn(void) 3995 { 3996 uint32_t ret; 3997 3998 ret = atomic_fetchadd_int(&number_of_tcp_connections_pacing, -1); 3999 shadow_num_connections = number_of_tcp_connections_pacing; 4000 KASSERT(ret != 0, ("tcp_paced_connection_exits -1 would cause wrap?")); 4001 if (ret == 0) { 4002 if (tcp_pacing_limit != -1) { 4003 printf("Warning all pacing is now disabled, count decrements invalidly!\n"); 4004 tcp_pacing_limit = 0; 4005 } else if (tcp_pacing_warning == 0) { 4006 printf("Warning pacing count is invalid, invalid decrement\n"); 4007 tcp_pacing_warning = 1; 4008 } 4009 } 4010 } 4011 4012 #ifdef TCP_ACCOUNTING 4013 int 4014 tcp_do_ack_accounting(struct tcpcb *tp, struct tcphdr *th, struct tcpopt *to, uint32_t tiwin, int mss) 4015 { 4016 if (SEQ_LT(th->th_ack, tp->snd_una)) { 4017 /* Do we have a SACK? */ 4018 if (to->to_flags & TOF_SACK) { 4019 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4020 tp->tcp_cnt_counters[ACK_SACK]++; 4021 } 4022 return (ACK_SACK); 4023 } else { 4024 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4025 tp->tcp_cnt_counters[ACK_BEHIND]++; 4026 } 4027 return (ACK_BEHIND); 4028 } 4029 } else if (th->th_ack == tp->snd_una) { 4030 /* Do we have a SACK? */ 4031 if (to->to_flags & TOF_SACK) { 4032 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4033 tp->tcp_cnt_counters[ACK_SACK]++; 4034 } 4035 return (ACK_SACK); 4036 } else if (tiwin != tp->snd_wnd) { 4037 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4038 tp->tcp_cnt_counters[ACK_RWND]++; 4039 } 4040 return (ACK_RWND); 4041 } else { 4042 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4043 tp->tcp_cnt_counters[ACK_DUPACK]++; 4044 } 4045 return (ACK_DUPACK); 4046 } 4047 } else { 4048 if (!SEQ_GT(th->th_ack, tp->snd_max)) { 4049 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4050 tp->tcp_cnt_counters[CNT_OF_ACKS_IN] += (((th->th_ack - tp->snd_una) + mss - 1)/mss); 4051 } 4052 } 4053 if (to->to_flags & TOF_SACK) { 4054 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4055 tp->tcp_cnt_counters[ACK_CUMACK_SACK]++; 4056 } 4057 return (ACK_CUMACK_SACK); 4058 } else { 4059 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4060 tp->tcp_cnt_counters[ACK_CUMACK]++; 4061 } 4062 return (ACK_CUMACK); 4063 } 4064 } 4065 } 4066 #endif 4067 4068 void 4069 tcp_change_time_units(struct tcpcb *tp, int granularity) 4070 { 4071 if (tp->t_tmr_granularity == granularity) { 4072 /* We are there */ 4073 return; 4074 } 4075 if (granularity == TCP_TMR_GRANULARITY_USEC) { 4076 KASSERT((tp->t_tmr_granularity == TCP_TMR_GRANULARITY_TICKS), 4077 ("Granularity is not TICKS its %u in tp:%p", 4078 tp->t_tmr_granularity, tp)); 4079 tp->t_rttlow = TICKS_2_USEC(tp->t_rttlow); 4080 if (tp->t_srtt > 1) { 4081 uint32_t val, frac; 4082 4083 val = tp->t_srtt >> TCP_RTT_SHIFT; 4084 frac = tp->t_srtt & 0x1f; 4085 tp->t_srtt = TICKS_2_USEC(val); 4086 /* 4087 * frac is the fractional part of the srtt (if any) 4088 * but its in ticks and every bit represents 4089 * 1/32nd of a hz. 4090 */ 4091 if (frac) { 4092 if (hz == 1000) { 4093 frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_MSEC) / (uint64_t)TCP_RTT_SCALE); 4094 } else { 4095 frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_SEC) / ((uint64_t)(hz) * (uint64_t)TCP_RTT_SCALE)); 4096 } 4097 tp->t_srtt += frac; 4098 } 4099 } 4100 if (tp->t_rttvar) { 4101 uint32_t val, frac; 4102 4103 val = tp->t_rttvar >> TCP_RTTVAR_SHIFT; 4104 frac = tp->t_rttvar & 0x1f; 4105 tp->t_rttvar = TICKS_2_USEC(val); 4106 /* 4107 * frac is the fractional part of the srtt (if any) 4108 * but its in ticks and every bit represents 4109 * 1/32nd of a hz. 4110 */ 4111 if (frac) { 4112 if (hz == 1000) { 4113 frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_MSEC) / (uint64_t)TCP_RTT_SCALE); 4114 } else { 4115 frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_SEC) / ((uint64_t)(hz) * (uint64_t)TCP_RTT_SCALE)); 4116 } 4117 tp->t_rttvar += frac; 4118 } 4119 } 4120 tp->t_tmr_granularity = TCP_TMR_GRANULARITY_USEC; 4121 } else if (granularity == TCP_TMR_GRANULARITY_TICKS) { 4122 /* Convert back to ticks, with */ 4123 KASSERT((tp->t_tmr_granularity == TCP_TMR_GRANULARITY_USEC), 4124 ("Granularity is not USEC its %u in tp:%p", 4125 tp->t_tmr_granularity, tp)); 4126 if (tp->t_srtt > 1) { 4127 uint32_t val, frac; 4128 4129 val = USEC_2_TICKS(tp->t_srtt); 4130 frac = tp->t_srtt % (HPTS_USEC_IN_SEC / hz); 4131 tp->t_srtt = val << TCP_RTT_SHIFT; 4132 /* 4133 * frac is the fractional part here is left 4134 * over from converting to hz and shifting. 4135 * We need to convert this to the 5 bit 4136 * remainder. 4137 */ 4138 if (frac) { 4139 if (hz == 1000) { 4140 frac = (((uint64_t)frac * (uint64_t)TCP_RTT_SCALE) / (uint64_t)HPTS_USEC_IN_MSEC); 4141 } else { 4142 frac = (((uint64_t)frac * (uint64_t)(hz) * (uint64_t)TCP_RTT_SCALE) /(uint64_t)HPTS_USEC_IN_SEC); 4143 } 4144 tp->t_srtt += frac; 4145 } 4146 } 4147 if (tp->t_rttvar) { 4148 uint32_t val, frac; 4149 4150 val = USEC_2_TICKS(tp->t_rttvar); 4151 frac = tp->t_srtt % (HPTS_USEC_IN_SEC / hz); 4152 tp->t_rttvar = val << TCP_RTTVAR_SHIFT; 4153 /* 4154 * frac is the fractional part here is left 4155 * over from converting to hz and shifting. 4156 * We need to convert this to the 5 bit 4157 * remainder. 4158 */ 4159 if (frac) { 4160 if (hz == 1000) { 4161 frac = (((uint64_t)frac * (uint64_t)TCP_RTT_SCALE) / (uint64_t)HPTS_USEC_IN_MSEC); 4162 } else { 4163 frac = (((uint64_t)frac * (uint64_t)(hz) * (uint64_t)TCP_RTT_SCALE) /(uint64_t)HPTS_USEC_IN_SEC); 4164 } 4165 tp->t_rttvar += frac; 4166 } 4167 } 4168 tp->t_rttlow = USEC_2_TICKS(tp->t_rttlow); 4169 tp->t_tmr_granularity = TCP_TMR_GRANULARITY_TICKS; 4170 } 4171 #ifdef INVARIANTS 4172 else { 4173 panic("Unknown granularity:%d tp:%p", 4174 granularity, tp); 4175 } 4176 #endif 4177 } 4178 4179 void 4180 tcp_handle_orphaned_packets(struct tcpcb *tp) 4181 { 4182 struct mbuf *save, *m, *prev; 4183 /* 4184 * Called when a stack switch is occuring from the fini() 4185 * of the old stack. We assue the init() as already been 4186 * run of the new stack and it has set the inp_flags2 to 4187 * what it supports. This function will then deal with any 4188 * differences i.e. cleanup packets that maybe queued that 4189 * the newstack does not support. 4190 */ 4191 4192 if (tptoinpcb(tp)->inp_flags2 & INP_MBUF_L_ACKS) 4193 return; 4194 if ((tptoinpcb(tp)->inp_flags2 & INP_SUPPORTS_MBUFQ) == 0) { 4195 /* 4196 * It is unsafe to process the packets since a 4197 * reset may be lurking in them (its rare but it 4198 * can occur). If we were to find a RST, then we 4199 * would end up dropping the connection and the 4200 * INP lock, so when we return the caller (tcp_usrreq) 4201 * will blow up when it trys to unlock the inp. 4202 * This new stack does not do any fancy LRO features 4203 * so all we can do is toss the packets. 4204 */ 4205 m = tp->t_in_pkt; 4206 tp->t_in_pkt = NULL; 4207 tp->t_tail_pkt = NULL; 4208 while (m) { 4209 save = m->m_nextpkt; 4210 m->m_nextpkt = NULL; 4211 m_freem(m); 4212 m = save; 4213 } 4214 } else { 4215 /* 4216 * Here we have a stack that does mbuf queuing but 4217 * does not support compressed ack's. We must 4218 * walk all the mbufs and discard any compressed acks. 4219 */ 4220 m = tp->t_in_pkt; 4221 prev = NULL; 4222 while (m) { 4223 if (m->m_flags & M_ACKCMP) { 4224 /* We must toss this packet */ 4225 if (tp->t_tail_pkt == m) 4226 tp->t_tail_pkt = prev; 4227 if (prev) 4228 prev->m_nextpkt = m->m_nextpkt; 4229 else 4230 tp->t_in_pkt = m->m_nextpkt; 4231 m->m_nextpkt = NULL; 4232 m_freem(m); 4233 /* move forward */ 4234 if (prev) 4235 m = prev->m_nextpkt; 4236 else 4237 m = tp->t_in_pkt; 4238 } else { 4239 /* this one is ok */ 4240 prev = m; 4241 m = m->m_nextpkt; 4242 } 4243 } 4244 } 4245 } 4246 4247 #ifdef TCP_REQUEST_TRK 4248 uint32_t 4249 tcp_estimate_tls_overhead(struct socket *so, uint64_t tls_usr_bytes) 4250 { 4251 #ifdef KERN_TLS 4252 struct ktls_session *tls; 4253 uint32_t rec_oh, records; 4254 4255 tls = so->so_snd.sb_tls_info; 4256 if (tls == NULL) 4257 return (0); 4258 4259 rec_oh = tls->params.tls_hlen + tls->params.tls_tlen; 4260 records = ((tls_usr_bytes + tls->params.max_frame_len - 1)/tls->params.max_frame_len); 4261 return (records * rec_oh); 4262 #else 4263 return (0); 4264 #endif 4265 } 4266 4267 extern uint32_t tcp_stale_entry_time; 4268 uint32_t tcp_stale_entry_time = 250000; 4269 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, usrlog_stale, CTLFLAG_RW, 4270 &tcp_stale_entry_time, 250000, "Time that a http entry without a sendfile ages out"); 4271 4272 void 4273 tcp_http_log_req_info(struct tcpcb *tp, struct http_sendfile_track *http, 4274 uint16_t slot, uint8_t val, uint64_t offset, uint64_t nbytes) 4275 { 4276 if (tcp_bblogging_on(tp)) { 4277 union tcp_log_stackspecific log; 4278 struct timeval tv; 4279 4280 memset(&log.u_bbr, 0, sizeof(log.u_bbr)); 4281 #ifdef TCPHPTS 4282 log.u_bbr.inhpts = tcp_in_hpts(tptoinpcb(tp)); 4283 #endif 4284 log.u_bbr.flex8 = val; 4285 log.u_bbr.rttProp = http->timestamp; 4286 log.u_bbr.delRate = http->start; 4287 log.u_bbr.cur_del_rate = http->end; 4288 log.u_bbr.flex1 = http->start_seq; 4289 log.u_bbr.flex2 = http->end_seq; 4290 log.u_bbr.flex3 = http->flags; 4291 log.u_bbr.flex4 = ((http->localtime >> 32) & 0x00000000ffffffff); 4292 log.u_bbr.flex5 = (http->localtime & 0x00000000ffffffff); 4293 log.u_bbr.flex7 = slot; 4294 log.u_bbr.bw_inuse = offset; 4295 /* nbytes = flex6 | epoch */ 4296 log.u_bbr.flex6 = ((nbytes >> 32) & 0x00000000ffffffff); 4297 log.u_bbr.epoch = (nbytes & 0x00000000ffffffff); 4298 /* cspr = lt_epoch | pkts_out */ 4299 log.u_bbr.lt_epoch = ((http->cspr >> 32) & 0x00000000ffffffff); 4300 log.u_bbr.pkts_out |= (http->cspr & 0x00000000ffffffff); 4301 log.u_bbr.applimited = tp->t_http_closed; 4302 log.u_bbr.applimited <<= 8; 4303 log.u_bbr.applimited |= tp->t_http_open; 4304 log.u_bbr.applimited <<= 8; 4305 log.u_bbr.applimited |= tp->t_http_req; 4306 log.u_bbr.timeStamp = tcp_get_usecs(&tv); 4307 TCP_LOG_EVENTP(tp, NULL, 4308 &tptosocket(tp)->so_rcv, 4309 &tptosocket(tp)->so_snd, 4310 TCP_LOG_HTTP_T, 0, 4311 0, &log, false, &tv); 4312 } 4313 } 4314 4315 void 4316 tcp_http_free_a_slot(struct tcpcb *tp, struct http_sendfile_track *ent) 4317 { 4318 if (tp->t_http_req > 0) 4319 tp->t_http_req--; 4320 if (ent->flags & TCP_HTTP_TRACK_FLG_OPEN) { 4321 if (tp->t_http_open > 0) 4322 tp->t_http_open--; 4323 } else { 4324 if (tp->t_http_closed > 0) 4325 tp->t_http_closed--; 4326 } 4327 ent->flags = TCP_HTTP_TRACK_FLG_EMPTY; 4328 } 4329 4330 static void 4331 tcp_http_check_for_stale_entries(struct tcpcb *tp, uint64_t ts, int rm_oldest) 4332 { 4333 struct http_sendfile_track *ent; 4334 uint64_t time_delta, oldest_delta; 4335 int i, oldest, oldest_set = 0, cnt_rm = 0; 4336 4337 for(i = 0; i < MAX_TCP_HTTP_REQ; i++) { 4338 ent = &tp->t_http_info[i]; 4339 if (ent->flags != TCP_HTTP_TRACK_FLG_USED) { 4340 /* 4341 * We only care about closed end ranges 4342 * that are allocated and have no sendfile 4343 * ever touching them. They would be in 4344 * state USED. 4345 */ 4346 continue; 4347 } 4348 if (ts >= ent->localtime) 4349 time_delta = ts - ent->localtime; 4350 else 4351 time_delta = 0; 4352 if (time_delta && 4353 ((oldest_delta < time_delta) || (oldest_set == 0))) { 4354 oldest_set = 1; 4355 oldest = i; 4356 oldest_delta = time_delta; 4357 } 4358 if (tcp_stale_entry_time && (time_delta >= tcp_stale_entry_time)) { 4359 /* 4360 * No sendfile in a our time-limit 4361 * time to purge it. 4362 */ 4363 cnt_rm++; 4364 tcp_http_log_req_info(tp, &tp->t_http_info[i], i, TCP_HTTP_REQ_LOG_STALE, 4365 time_delta, 0); 4366 tcp_http_free_a_slot(tp, ent); 4367 } 4368 } 4369 if ((cnt_rm == 0) && rm_oldest && oldest_set) { 4370 ent = &tp->t_http_info[oldest]; 4371 tcp_http_log_req_info(tp, &tp->t_http_info[i], i, TCP_HTTP_REQ_LOG_STALE, 4372 oldest_delta, 1); 4373 tcp_http_free_a_slot(tp, ent); 4374 } 4375 } 4376 4377 int 4378 tcp_http_check_for_comp(struct tcpcb *tp, tcp_seq ack_point) 4379 { 4380 int i, ret=0; 4381 struct http_sendfile_track *ent; 4382 4383 /* Clean up any old closed end requests that are now completed */ 4384 if (tp->t_http_req == 0) 4385 return(0); 4386 if (tp->t_http_closed == 0) 4387 return(0); 4388 for(i = 0; i < MAX_TCP_HTTP_REQ; i++) { 4389 ent = &tp->t_http_info[i]; 4390 /* Skip empty ones */ 4391 if (ent->flags == TCP_HTTP_TRACK_FLG_EMPTY) 4392 continue; 4393 /* Skip open ones */ 4394 if (ent->flags & TCP_HTTP_TRACK_FLG_OPEN) 4395 continue; 4396 if (SEQ_GEQ(ack_point, ent->end_seq)) { 4397 /* We are past it -- free it */ 4398 tcp_http_log_req_info(tp, ent, 4399 i, TCP_HTTP_REQ_LOG_FREED, 0, 0); 4400 tcp_http_free_a_slot(tp, ent); 4401 ret++; 4402 } 4403 } 4404 return (ret); 4405 } 4406 4407 int 4408 tcp_http_is_entry_comp(struct tcpcb *tp, struct http_sendfile_track *ent, tcp_seq ack_point) 4409 { 4410 if (tp->t_http_req == 0) 4411 return(-1); 4412 if (tp->t_http_closed == 0) 4413 return(-1); 4414 if (ent->flags == TCP_HTTP_TRACK_FLG_EMPTY) 4415 return(-1); 4416 if (SEQ_GEQ(ack_point, ent->end_seq)) { 4417 return (1); 4418 } 4419 return (0); 4420 } 4421 4422 struct http_sendfile_track * 4423 tcp_http_find_a_req_that_is_completed_by(struct tcpcb *tp, tcp_seq th_ack, int *ip) 4424 { 4425 /* 4426 * Given an ack point (th_ack) walk through our entries and 4427 * return the first one found that th_ack goes past the 4428 * end_seq. 4429 */ 4430 struct http_sendfile_track *ent; 4431 int i; 4432 4433 if (tp->t_http_req == 0) { 4434 /* none open */ 4435 return (NULL); 4436 } 4437 for(i = 0; i < MAX_TCP_HTTP_REQ; i++) { 4438 ent = &tp->t_http_info[i]; 4439 if (ent->flags == TCP_HTTP_TRACK_FLG_EMPTY) 4440 continue; 4441 if ((ent->flags & TCP_HTTP_TRACK_FLG_OPEN) == 0) { 4442 if (SEQ_GEQ(th_ack, ent->end_seq)) { 4443 *ip = i; 4444 return (ent); 4445 } 4446 } 4447 } 4448 return (NULL); 4449 } 4450 4451 struct http_sendfile_track * 4452 tcp_http_find_req_for_seq(struct tcpcb *tp, tcp_seq seq) 4453 { 4454 struct http_sendfile_track *ent; 4455 int i; 4456 4457 if (tp->t_http_req == 0) { 4458 /* none open */ 4459 return (NULL); 4460 } 4461 for(i = 0; i < MAX_TCP_HTTP_REQ; i++) { 4462 ent = &tp->t_http_info[i]; 4463 tcp_http_log_req_info(tp, ent, i, TCP_HTTP_REQ_LOG_SEARCH, 4464 (uint64_t)seq, 0); 4465 if (ent->flags == TCP_HTTP_TRACK_FLG_EMPTY) { 4466 continue; 4467 } 4468 if (ent->flags & TCP_HTTP_TRACK_FLG_OPEN) { 4469 /* 4470 * An open end request only needs to 4471 * match the beginning seq or be 4472 * all we have (once we keep going on 4473 * a open end request we may have a seq 4474 * wrap). 4475 */ 4476 if ((SEQ_GEQ(seq, ent->start_seq)) || 4477 (tp->t_http_closed == 0)) 4478 return (ent); 4479 } else { 4480 /* 4481 * For this one we need to 4482 * be a bit more careful if its 4483 * completed at least. 4484 */ 4485 if ((SEQ_GEQ(seq, ent->start_seq)) && 4486 (SEQ_LT(seq, ent->end_seq))) { 4487 return (ent); 4488 } 4489 } 4490 } 4491 return (NULL); 4492 } 4493 4494 /* Should this be in its own file tcp_http.c ? */ 4495 struct http_sendfile_track * 4496 tcp_http_alloc_req_full(struct tcpcb *tp, struct http_req *req, uint64_t ts, int rec_dups) 4497 { 4498 struct http_sendfile_track *fil; 4499 int i, allocated; 4500 4501 /* In case the stack does not check for completions do so now */ 4502 tcp_http_check_for_comp(tp, tp->snd_una); 4503 /* Check for stale entries */ 4504 if (tp->t_http_req) 4505 tcp_http_check_for_stale_entries(tp, ts, 4506 (tp->t_http_req >= MAX_TCP_HTTP_REQ)); 4507 /* Check to see if this is a duplicate of one not started */ 4508 if (tp->t_http_req) { 4509 for(i = 0, allocated = 0; i < MAX_TCP_HTTP_REQ; i++) { 4510 fil = &tp->t_http_info[i]; 4511 if (fil->flags != TCP_HTTP_TRACK_FLG_USED) 4512 continue; 4513 if ((fil->timestamp == req->timestamp) && 4514 (fil->start == req->start) && 4515 ((fil->flags & TCP_HTTP_TRACK_FLG_OPEN) || 4516 (fil->end == req->end))) { 4517 /* 4518 * We already have this request 4519 * and it has not been started with sendfile. 4520 * This probably means the user was returned 4521 * a 4xx of some sort and its going to age 4522 * out, lets not duplicate it. 4523 */ 4524 return(fil); 4525 } 4526 } 4527 } 4528 /* Ok if there is no room at the inn we are in trouble */ 4529 if (tp->t_http_req >= MAX_TCP_HTTP_REQ) { 4530 tcp_trace_point(tp, TCP_TP_HTTP_LOG_FAIL); 4531 for(i = 0; i < MAX_TCP_HTTP_REQ; i++) { 4532 tcp_http_log_req_info(tp, &tp->t_http_info[i], 4533 i, TCP_HTTP_REQ_LOG_ALLOCFAIL, 0, 0); 4534 } 4535 return (NULL); 4536 } 4537 for(i = 0, allocated = 0; i < MAX_TCP_HTTP_REQ; i++) { 4538 fil = &tp->t_http_info[i]; 4539 if (fil->flags == TCP_HTTP_TRACK_FLG_EMPTY) { 4540 allocated = 1; 4541 fil->flags = TCP_HTTP_TRACK_FLG_USED; 4542 fil->timestamp = req->timestamp; 4543 fil->localtime = ts; 4544 fil->start = req->start; 4545 if (req->flags & TCP_LOG_HTTPD_RANGE_END) { 4546 fil->end = req->end; 4547 } else { 4548 fil->end = 0; 4549 fil->flags |= TCP_HTTP_TRACK_FLG_OPEN; 4550 } 4551 /* 4552 * We can set the min boundaries to the TCP Sequence space, 4553 * but it might be found to be further up when sendfile 4554 * actually runs on this range (if it ever does). 4555 */ 4556 fil->sbcc_at_s = tptosocket(tp)->so_snd.sb_ccc; 4557 fil->start_seq = tp->snd_una + 4558 tptosocket(tp)->so_snd.sb_ccc; 4559 fil->end_seq = (fil->start_seq + ((uint32_t)(fil->end - fil->start))); 4560 if (tptosocket(tp)->so_snd.sb_tls_info) { 4561 /* 4562 * This session is doing TLS. Take a swag guess 4563 * at the overhead. 4564 */ 4565 fil->end_seq += tcp_estimate_tls_overhead( 4566 tptosocket(tp), (fil->end - fil->start)); 4567 } 4568 tp->t_http_req++; 4569 if (fil->flags & TCP_HTTP_TRACK_FLG_OPEN) 4570 tp->t_http_open++; 4571 else 4572 tp->t_http_closed++; 4573 tcp_http_log_req_info(tp, fil, i, 4574 TCP_HTTP_REQ_LOG_NEW, 0, 0); 4575 break; 4576 } else 4577 fil = NULL; 4578 } 4579 return (fil); 4580 } 4581 4582 void 4583 tcp_http_alloc_req(struct tcpcb *tp, union tcp_log_userdata *user, uint64_t ts) 4584 { 4585 (void)tcp_http_alloc_req_full(tp, &user->http_req, ts, 1); 4586 } 4587 #endif 4588 4589 void 4590 tcp_log_socket_option(struct tcpcb *tp, uint32_t option_num, uint32_t option_val, int err) 4591 { 4592 if (tcp_bblogging_on(tp)) { 4593 struct tcp_log_buffer *l; 4594 4595 l = tcp_log_event(tp, NULL, 4596 &tptosocket(tp)->so_rcv, 4597 &tptosocket(tp)->so_snd, 4598 TCP_LOG_SOCKET_OPT, 4599 err, 0, NULL, 1, 4600 NULL, NULL, 0, NULL); 4601 if (l) { 4602 l->tlb_flex1 = option_num; 4603 l->tlb_flex2 = option_val; 4604 } 4605 } 4606 } 4607