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 = 450; /* 45 % (sack:2:ack -25%) (mv:ratio -15%) **/ 172 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, restore_thresh, 173 CTLFLAG_RW, 174 &tcp_restoral_thresh, 450, 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 static counter_u64_t tcp_pacing_failures; 294 295 static int tcp_pacing_limit = 10000; 296 SYSCTL_INT(_net_inet_tcp, OID_AUTO, pacing_limit, CTLFLAG_RW, 297 &tcp_pacing_limit, 1000, 298 "If the TCP stack does pacing, is there a limit (-1 = no, 0 = no pacing N = number of connections)"); 299 300 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, pacing_count, CTLFLAG_RD, 301 &shadow_num_connections, 0, "Number of TCP connections being paced"); 302 303 SYSCTL_COUNTER_U64(_net_inet_tcp, OID_AUTO, pacing_failures, CTLFLAG_RD, 304 &tcp_pacing_failures, "Number of times we failed to enable pacing to avoid exceeding the limit"); 305 306 static int tcp_log_debug = 0; 307 SYSCTL_INT(_net_inet_tcp, OID_AUTO, log_debug, CTLFLAG_RW, 308 &tcp_log_debug, 0, "Log errors caused by incoming TCP segments"); 309 310 static int tcp_tcbhashsize; 311 SYSCTL_INT(_net_inet_tcp, OID_AUTO, tcbhashsize, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, 312 &tcp_tcbhashsize, 0, "Size of TCP control-block hashtable"); 313 314 static int do_tcpdrain = 1; 315 SYSCTL_INT(_net_inet_tcp, OID_AUTO, do_tcpdrain, CTLFLAG_RW, &do_tcpdrain, 0, 316 "Enable tcp_drain routine for extra help when low on mbufs"); 317 318 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, pcbcount, CTLFLAG_VNET | CTLFLAG_RD, 319 &VNET_NAME(tcbinfo.ipi_count), 0, "Number of active PCBs"); 320 321 VNET_DEFINE_STATIC(int, icmp_may_rst) = 1; 322 #define V_icmp_may_rst VNET(icmp_may_rst) 323 SYSCTL_INT(_net_inet_tcp, OID_AUTO, icmp_may_rst, CTLFLAG_VNET | CTLFLAG_RW, 324 &VNET_NAME(icmp_may_rst), 0, 325 "Certain ICMP unreachable messages may abort connections in SYN_SENT"); 326 327 VNET_DEFINE_STATIC(int, tcp_isn_reseed_interval) = 0; 328 #define V_tcp_isn_reseed_interval VNET(tcp_isn_reseed_interval) 329 SYSCTL_INT(_net_inet_tcp, OID_AUTO, isn_reseed_interval, CTLFLAG_VNET | CTLFLAG_RW, 330 &VNET_NAME(tcp_isn_reseed_interval), 0, 331 "Seconds between reseeding of ISN secret"); 332 333 static int tcp_soreceive_stream; 334 SYSCTL_INT(_net_inet_tcp, OID_AUTO, soreceive_stream, CTLFLAG_RDTUN, 335 &tcp_soreceive_stream, 0, "Using soreceive_stream for TCP sockets"); 336 337 VNET_DEFINE(uma_zone_t, sack_hole_zone); 338 #define V_sack_hole_zone VNET(sack_hole_zone) 339 VNET_DEFINE(uint32_t, tcp_map_entries_limit) = 0; /* unlimited */ 340 static int 341 sysctl_net_inet_tcp_map_limit_check(SYSCTL_HANDLER_ARGS) 342 { 343 int error; 344 uint32_t new; 345 346 new = V_tcp_map_entries_limit; 347 error = sysctl_handle_int(oidp, &new, 0, req); 348 if (error == 0 && req->newptr) { 349 /* only allow "0" and value > minimum */ 350 if (new > 0 && new < TCP_MIN_MAP_ENTRIES_LIMIT) 351 error = EINVAL; 352 else 353 V_tcp_map_entries_limit = new; 354 } 355 return (error); 356 } 357 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, map_limit, 358 CTLFLAG_VNET | CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 359 &VNET_NAME(tcp_map_entries_limit), 0, 360 &sysctl_net_inet_tcp_map_limit_check, "IU", 361 "Total sendmap entries limit"); 362 363 VNET_DEFINE(uint32_t, tcp_map_split_limit) = 0; /* unlimited */ 364 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, split_limit, CTLFLAG_VNET | CTLFLAG_RW, 365 &VNET_NAME(tcp_map_split_limit), 0, 366 "Total sendmap split entries limit"); 367 368 #ifdef TCP_HHOOK 369 VNET_DEFINE(struct hhook_head *, tcp_hhh[HHOOK_TCP_LAST+1]); 370 #endif 371 372 #define TS_OFFSET_SECRET_LENGTH SIPHASH_KEY_LENGTH 373 VNET_DEFINE_STATIC(u_char, ts_offset_secret[TS_OFFSET_SECRET_LENGTH]); 374 #define V_ts_offset_secret VNET(ts_offset_secret) 375 376 static int tcp_default_fb_init(struct tcpcb *tp, void **ptr); 377 static void tcp_default_fb_fini(struct tcpcb *tp, int tcb_is_purged); 378 static int tcp_default_handoff_ok(struct tcpcb *tp); 379 static struct inpcb *tcp_notify(struct inpcb *, int); 380 static struct inpcb *tcp_mtudisc_notify(struct inpcb *, int); 381 static struct inpcb *tcp_mtudisc(struct inpcb *, int); 382 static struct inpcb *tcp_drop_syn_sent(struct inpcb *, int); 383 static char * tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th, 384 const void *ip4hdr, const void *ip6hdr); 385 static void tcp_default_switch_failed(struct tcpcb *tp); 386 static ipproto_ctlinput_t tcp_ctlinput; 387 static udp_tun_icmp_t tcp_ctlinput_viaudp; 388 389 static struct tcp_function_block tcp_def_funcblk = { 390 .tfb_tcp_block_name = "freebsd", 391 .tfb_tcp_output = tcp_default_output, 392 .tfb_tcp_do_segment = tcp_do_segment, 393 .tfb_tcp_ctloutput = tcp_default_ctloutput, 394 .tfb_tcp_handoff_ok = tcp_default_handoff_ok, 395 .tfb_tcp_fb_init = tcp_default_fb_init, 396 .tfb_tcp_fb_fini = tcp_default_fb_fini, 397 .tfb_switch_failed = tcp_default_switch_failed, 398 }; 399 400 static int tcp_fb_cnt = 0; 401 struct tcp_funchead t_functions; 402 VNET_DEFINE_STATIC(struct tcp_function_block *, tcp_func_set_ptr) = &tcp_def_funcblk; 403 #define V_tcp_func_set_ptr VNET(tcp_func_set_ptr) 404 405 void 406 tcp_record_dsack(struct tcpcb *tp, tcp_seq start, tcp_seq end, int tlp) 407 { 408 TCPSTAT_INC(tcps_dsack_count); 409 tp->t_dsack_pack++; 410 if (tlp == 0) { 411 if (SEQ_GT(end, start)) { 412 tp->t_dsack_bytes += (end - start); 413 TCPSTAT_ADD(tcps_dsack_bytes, (end - start)); 414 } else { 415 tp->t_dsack_tlp_bytes += (start - end); 416 TCPSTAT_ADD(tcps_dsack_bytes, (start - end)); 417 } 418 } else { 419 if (SEQ_GT(end, start)) { 420 tp->t_dsack_bytes += (end - start); 421 TCPSTAT_ADD(tcps_dsack_tlp_bytes, (end - start)); 422 } else { 423 tp->t_dsack_tlp_bytes += (start - end); 424 TCPSTAT_ADD(tcps_dsack_tlp_bytes, (start - end)); 425 } 426 } 427 } 428 429 static struct tcp_function_block * 430 find_tcp_functions_locked(struct tcp_function_set *fs) 431 { 432 struct tcp_function *f; 433 struct tcp_function_block *blk=NULL; 434 435 TAILQ_FOREACH(f, &t_functions, tf_next) { 436 if (strcmp(f->tf_name, fs->function_set_name) == 0) { 437 blk = f->tf_fb; 438 break; 439 } 440 } 441 return(blk); 442 } 443 444 static struct tcp_function_block * 445 find_tcp_fb_locked(struct tcp_function_block *blk, struct tcp_function **s) 446 { 447 struct tcp_function_block *rblk=NULL; 448 struct tcp_function *f; 449 450 TAILQ_FOREACH(f, &t_functions, tf_next) { 451 if (f->tf_fb == blk) { 452 rblk = blk; 453 if (s) { 454 *s = f; 455 } 456 break; 457 } 458 } 459 return (rblk); 460 } 461 462 struct tcp_function_block * 463 find_and_ref_tcp_functions(struct tcp_function_set *fs) 464 { 465 struct tcp_function_block *blk; 466 467 rw_rlock(&tcp_function_lock); 468 blk = find_tcp_functions_locked(fs); 469 if (blk) 470 refcount_acquire(&blk->tfb_refcnt); 471 rw_runlock(&tcp_function_lock); 472 return(blk); 473 } 474 475 struct tcp_function_block * 476 find_and_ref_tcp_fb(struct tcp_function_block *blk) 477 { 478 struct tcp_function_block *rblk; 479 480 rw_rlock(&tcp_function_lock); 481 rblk = find_tcp_fb_locked(blk, NULL); 482 if (rblk) 483 refcount_acquire(&rblk->tfb_refcnt); 484 rw_runlock(&tcp_function_lock); 485 return(rblk); 486 } 487 488 /* Find a matching alias for the given tcp_function_block. */ 489 int 490 find_tcp_function_alias(struct tcp_function_block *blk, 491 struct tcp_function_set *fs) 492 { 493 struct tcp_function *f; 494 int found; 495 496 found = 0; 497 rw_rlock(&tcp_function_lock); 498 TAILQ_FOREACH(f, &t_functions, tf_next) { 499 if ((f->tf_fb == blk) && 500 (strncmp(f->tf_name, blk->tfb_tcp_block_name, 501 TCP_FUNCTION_NAME_LEN_MAX) != 0)) { 502 /* Matching function block with different name. */ 503 strncpy(fs->function_set_name, f->tf_name, 504 TCP_FUNCTION_NAME_LEN_MAX); 505 found = 1; 506 break; 507 } 508 } 509 /* Null terminate the string appropriately. */ 510 if (found) { 511 fs->function_set_name[TCP_FUNCTION_NAME_LEN_MAX - 1] = '\0'; 512 } else { 513 fs->function_set_name[0] = '\0'; 514 } 515 rw_runlock(&tcp_function_lock); 516 return (found); 517 } 518 519 static struct tcp_function_block * 520 find_and_ref_tcp_default_fb(void) 521 { 522 struct tcp_function_block *rblk; 523 524 rw_rlock(&tcp_function_lock); 525 rblk = V_tcp_func_set_ptr; 526 refcount_acquire(&rblk->tfb_refcnt); 527 rw_runlock(&tcp_function_lock); 528 return (rblk); 529 } 530 531 void 532 tcp_switch_back_to_default(struct tcpcb *tp) 533 { 534 struct tcp_function_block *tfb; 535 void *ptr = NULL; 536 537 KASSERT(tp->t_fb != &tcp_def_funcblk, 538 ("%s: called by the built-in default stack", __func__)); 539 540 /* 541 * Now, we'll find a new function block to use. 542 * Start by trying the current user-selected 543 * default, unless this stack is the user-selected 544 * default. 545 */ 546 tfb = find_and_ref_tcp_default_fb(); 547 if (tfb == tp->t_fb) { 548 refcount_release(&tfb->tfb_refcnt); 549 tfb = NULL; 550 } 551 /* Does the stack accept this connection? */ 552 if (tfb != NULL && tfb->tfb_tcp_handoff_ok != NULL && 553 (*tfb->tfb_tcp_handoff_ok)(tp)) { 554 refcount_release(&tfb->tfb_refcnt); 555 tfb = NULL; 556 } 557 /* Try to use that stack. */ 558 if (tfb != NULL) { 559 /* Initialize the new stack. If it succeeds, we are done. */ 560 if (tfb->tfb_tcp_fb_init == NULL || 561 (*tfb->tfb_tcp_fb_init)(tp, &ptr) == 0) { 562 /* Release the old stack */ 563 if (tp->t_fb->tfb_tcp_fb_fini != NULL) 564 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 0); 565 refcount_release(&tp->t_fb->tfb_refcnt); 566 /* Now set in all the pointers */ 567 tp->t_fb = tfb; 568 tp->t_fb_ptr = ptr; 569 return; 570 } 571 /* 572 * Initialization failed. Release the reference count on 573 * the looked up default stack. 574 */ 575 refcount_release(&tfb->tfb_refcnt); 576 } 577 578 /* 579 * If that wasn't feasible, use the built-in default 580 * stack which is not allowed to reject anyone. 581 */ 582 tfb = find_and_ref_tcp_fb(&tcp_def_funcblk); 583 if (tfb == NULL) { 584 /* there always should be a default */ 585 panic("Can't refer to tcp_def_funcblk"); 586 } 587 if (tfb->tfb_tcp_handoff_ok != NULL) { 588 if ((*tfb->tfb_tcp_handoff_ok) (tp)) { 589 /* The default stack cannot say no */ 590 panic("Default stack rejects a new session?"); 591 } 592 } 593 if (tfb->tfb_tcp_fb_init != NULL && 594 (*tfb->tfb_tcp_fb_init)(tp, &ptr)) { 595 /* The default stack cannot fail */ 596 panic("Default stack initialization failed"); 597 } 598 /* Now release the old stack */ 599 if (tp->t_fb->tfb_tcp_fb_fini != NULL) 600 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 0); 601 refcount_release(&tp->t_fb->tfb_refcnt); 602 /* And set in the pointers to the new */ 603 tp->t_fb = tfb; 604 tp->t_fb_ptr = ptr; 605 } 606 607 static bool 608 tcp_recv_udp_tunneled_packet(struct mbuf *m, int off, struct inpcb *inp, 609 const struct sockaddr *sa, void *ctx) 610 { 611 struct ip *iph; 612 #ifdef INET6 613 struct ip6_hdr *ip6; 614 #endif 615 struct udphdr *uh; 616 struct tcphdr *th; 617 int thlen; 618 uint16_t port; 619 620 TCPSTAT_INC(tcps_tunneled_pkts); 621 if ((m->m_flags & M_PKTHDR) == 0) { 622 /* Can't handle one that is not a pkt hdr */ 623 TCPSTAT_INC(tcps_tunneled_errs); 624 goto out; 625 } 626 thlen = sizeof(struct tcphdr); 627 if (m->m_len < off + sizeof(struct udphdr) + thlen && 628 (m = m_pullup(m, off + sizeof(struct udphdr) + thlen)) == NULL) { 629 TCPSTAT_INC(tcps_tunneled_errs); 630 goto out; 631 } 632 iph = mtod(m, struct ip *); 633 uh = (struct udphdr *)((caddr_t)iph + off); 634 th = (struct tcphdr *)(uh + 1); 635 thlen = th->th_off << 2; 636 if (m->m_len < off + sizeof(struct udphdr) + thlen) { 637 m = m_pullup(m, off + sizeof(struct udphdr) + thlen); 638 if (m == NULL) { 639 TCPSTAT_INC(tcps_tunneled_errs); 640 goto out; 641 } else { 642 iph = mtod(m, struct ip *); 643 uh = (struct udphdr *)((caddr_t)iph + off); 644 th = (struct tcphdr *)(uh + 1); 645 } 646 } 647 m->m_pkthdr.tcp_tun_port = port = uh->uh_sport; 648 bcopy(th, uh, m->m_len - off); 649 m->m_len -= sizeof(struct udphdr); 650 m->m_pkthdr.len -= sizeof(struct udphdr); 651 /* 652 * We use the same algorithm for 653 * both UDP and TCP for c-sum. So 654 * the code in tcp_input will skip 655 * the checksum. So we do nothing 656 * with the flag (m->m_pkthdr.csum_flags). 657 */ 658 switch (iph->ip_v) { 659 #ifdef INET 660 case IPVERSION: 661 iph->ip_len = htons(ntohs(iph->ip_len) - sizeof(struct udphdr)); 662 tcp_input_with_port(&m, &off, IPPROTO_TCP, port); 663 break; 664 #endif 665 #ifdef INET6 666 case IPV6_VERSION >> 4: 667 ip6 = mtod(m, struct ip6_hdr *); 668 ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - sizeof(struct udphdr)); 669 tcp6_input_with_port(&m, &off, IPPROTO_TCP, port); 670 break; 671 #endif 672 default: 673 goto out; 674 break; 675 } 676 return (true); 677 out: 678 m_freem(m); 679 680 return (true); 681 } 682 683 static int 684 sysctl_net_inet_default_tcp_functions(SYSCTL_HANDLER_ARGS) 685 { 686 int error=ENOENT; 687 struct tcp_function_set fs; 688 struct tcp_function_block *blk; 689 690 memset(&fs, 0, sizeof(fs)); 691 rw_rlock(&tcp_function_lock); 692 blk = find_tcp_fb_locked(V_tcp_func_set_ptr, NULL); 693 if (blk) { 694 /* Found him */ 695 strcpy(fs.function_set_name, blk->tfb_tcp_block_name); 696 fs.pcbcnt = blk->tfb_refcnt; 697 } 698 rw_runlock(&tcp_function_lock); 699 error = sysctl_handle_string(oidp, fs.function_set_name, 700 sizeof(fs.function_set_name), req); 701 702 /* Check for error or no change */ 703 if (error != 0 || req->newptr == NULL) 704 return(error); 705 706 rw_wlock(&tcp_function_lock); 707 blk = find_tcp_functions_locked(&fs); 708 if ((blk == NULL) || 709 (blk->tfb_flags & TCP_FUNC_BEING_REMOVED)) { 710 error = ENOENT; 711 goto done; 712 } 713 V_tcp_func_set_ptr = blk; 714 done: 715 rw_wunlock(&tcp_function_lock); 716 return (error); 717 } 718 719 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, functions_default, 720 CTLFLAG_VNET | CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 721 NULL, 0, sysctl_net_inet_default_tcp_functions, "A", 722 "Set/get the default TCP functions"); 723 724 static int 725 sysctl_net_inet_list_available(SYSCTL_HANDLER_ARGS) 726 { 727 int error, cnt, linesz; 728 struct tcp_function *f; 729 char *buffer, *cp; 730 size_t bufsz, outsz; 731 bool alias; 732 733 cnt = 0; 734 rw_rlock(&tcp_function_lock); 735 TAILQ_FOREACH(f, &t_functions, tf_next) { 736 cnt++; 737 } 738 rw_runlock(&tcp_function_lock); 739 740 bufsz = (cnt+2) * ((TCP_FUNCTION_NAME_LEN_MAX * 2) + 13) + 1; 741 buffer = malloc(bufsz, M_TEMP, M_WAITOK); 742 743 error = 0; 744 cp = buffer; 745 746 linesz = snprintf(cp, bufsz, "\n%-32s%c %-32s %s\n", "Stack", 'D', 747 "Alias", "PCB count"); 748 cp += linesz; 749 bufsz -= linesz; 750 outsz = linesz; 751 752 rw_rlock(&tcp_function_lock); 753 TAILQ_FOREACH(f, &t_functions, tf_next) { 754 alias = (f->tf_name != f->tf_fb->tfb_tcp_block_name); 755 linesz = snprintf(cp, bufsz, "%-32s%c %-32s %u\n", 756 f->tf_fb->tfb_tcp_block_name, 757 (f->tf_fb == V_tcp_func_set_ptr) ? '*' : ' ', 758 alias ? f->tf_name : "-", 759 f->tf_fb->tfb_refcnt); 760 if (linesz >= bufsz) { 761 error = EOVERFLOW; 762 break; 763 } 764 cp += linesz; 765 bufsz -= linesz; 766 outsz += linesz; 767 } 768 rw_runlock(&tcp_function_lock); 769 if (error == 0) 770 error = sysctl_handle_string(oidp, buffer, outsz + 1, req); 771 free(buffer, M_TEMP); 772 return (error); 773 } 774 775 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, functions_available, 776 CTLFLAG_VNET | CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT, 777 NULL, 0, sysctl_net_inet_list_available, "A", 778 "list available TCP Function sets"); 779 780 VNET_DEFINE(int, tcp_udp_tunneling_port) = TCP_TUNNELING_PORT_DEFAULT; 781 782 #ifdef INET 783 VNET_DEFINE(struct socket *, udp4_tun_socket) = NULL; 784 #define V_udp4_tun_socket VNET(udp4_tun_socket) 785 #endif 786 #ifdef INET6 787 VNET_DEFINE(struct socket *, udp6_tun_socket) = NULL; 788 #define V_udp6_tun_socket VNET(udp6_tun_socket) 789 #endif 790 791 static struct sx tcpoudp_lock; 792 793 static void 794 tcp_over_udp_stop(void) 795 { 796 797 sx_assert(&tcpoudp_lock, SA_XLOCKED); 798 799 #ifdef INET 800 if (V_udp4_tun_socket != NULL) { 801 soclose(V_udp4_tun_socket); 802 V_udp4_tun_socket = NULL; 803 } 804 #endif 805 #ifdef INET6 806 if (V_udp6_tun_socket != NULL) { 807 soclose(V_udp6_tun_socket); 808 V_udp6_tun_socket = NULL; 809 } 810 #endif 811 } 812 813 static int 814 tcp_over_udp_start(void) 815 { 816 uint16_t port; 817 int ret; 818 #ifdef INET 819 struct sockaddr_in sin; 820 #endif 821 #ifdef INET6 822 struct sockaddr_in6 sin6; 823 #endif 824 825 sx_assert(&tcpoudp_lock, SA_XLOCKED); 826 827 port = V_tcp_udp_tunneling_port; 828 if (ntohs(port) == 0) { 829 /* Must have a port set */ 830 return (EINVAL); 831 } 832 #ifdef INET 833 if (V_udp4_tun_socket != NULL) { 834 /* Already running -- must stop first */ 835 return (EALREADY); 836 } 837 #endif 838 #ifdef INET6 839 if (V_udp6_tun_socket != NULL) { 840 /* Already running -- must stop first */ 841 return (EALREADY); 842 } 843 #endif 844 #ifdef INET 845 if ((ret = socreate(PF_INET, &V_udp4_tun_socket, 846 SOCK_DGRAM, IPPROTO_UDP, 847 curthread->td_ucred, curthread))) { 848 tcp_over_udp_stop(); 849 return (ret); 850 } 851 /* Call the special UDP hook. */ 852 if ((ret = udp_set_kernel_tunneling(V_udp4_tun_socket, 853 tcp_recv_udp_tunneled_packet, 854 tcp_ctlinput_viaudp, 855 NULL))) { 856 tcp_over_udp_stop(); 857 return (ret); 858 } 859 /* Ok, we have a socket, bind it to the port. */ 860 memset(&sin, 0, sizeof(struct sockaddr_in)); 861 sin.sin_len = sizeof(struct sockaddr_in); 862 sin.sin_family = AF_INET; 863 sin.sin_port = htons(port); 864 if ((ret = sobind(V_udp4_tun_socket, 865 (struct sockaddr *)&sin, curthread))) { 866 tcp_over_udp_stop(); 867 return (ret); 868 } 869 #endif 870 #ifdef INET6 871 if ((ret = socreate(PF_INET6, &V_udp6_tun_socket, 872 SOCK_DGRAM, IPPROTO_UDP, 873 curthread->td_ucred, curthread))) { 874 tcp_over_udp_stop(); 875 return (ret); 876 } 877 /* Call the special UDP hook. */ 878 if ((ret = udp_set_kernel_tunneling(V_udp6_tun_socket, 879 tcp_recv_udp_tunneled_packet, 880 tcp6_ctlinput_viaudp, 881 NULL))) { 882 tcp_over_udp_stop(); 883 return (ret); 884 } 885 /* Ok, we have a socket, bind it to the port. */ 886 memset(&sin6, 0, sizeof(struct sockaddr_in6)); 887 sin6.sin6_len = sizeof(struct sockaddr_in6); 888 sin6.sin6_family = AF_INET6; 889 sin6.sin6_port = htons(port); 890 if ((ret = sobind(V_udp6_tun_socket, 891 (struct sockaddr *)&sin6, curthread))) { 892 tcp_over_udp_stop(); 893 return (ret); 894 } 895 #endif 896 return (0); 897 } 898 899 static int 900 sysctl_net_inet_tcp_udp_tunneling_port_check(SYSCTL_HANDLER_ARGS) 901 { 902 int error; 903 uint32_t old, new; 904 905 old = V_tcp_udp_tunneling_port; 906 new = old; 907 error = sysctl_handle_int(oidp, &new, 0, req); 908 if ((error == 0) && 909 (req->newptr != NULL)) { 910 if ((new < TCP_TUNNELING_PORT_MIN) || 911 (new > TCP_TUNNELING_PORT_MAX)) { 912 error = EINVAL; 913 } else { 914 sx_xlock(&tcpoudp_lock); 915 V_tcp_udp_tunneling_port = new; 916 if (old != 0) { 917 tcp_over_udp_stop(); 918 } 919 if (new != 0) { 920 error = tcp_over_udp_start(); 921 if (error != 0) { 922 V_tcp_udp_tunneling_port = 0; 923 } 924 } 925 sx_xunlock(&tcpoudp_lock); 926 } 927 } 928 return (error); 929 } 930 931 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, udp_tunneling_port, 932 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 933 &VNET_NAME(tcp_udp_tunneling_port), 934 0, &sysctl_net_inet_tcp_udp_tunneling_port_check, "IU", 935 "Tunneling port for tcp over udp"); 936 937 VNET_DEFINE(int, tcp_udp_tunneling_overhead) = TCP_TUNNELING_OVERHEAD_DEFAULT; 938 939 static int 940 sysctl_net_inet_tcp_udp_tunneling_overhead_check(SYSCTL_HANDLER_ARGS) 941 { 942 int error, new; 943 944 new = V_tcp_udp_tunneling_overhead; 945 error = sysctl_handle_int(oidp, &new, 0, req); 946 if (error == 0 && req->newptr) { 947 if ((new < TCP_TUNNELING_OVERHEAD_MIN) || 948 (new > TCP_TUNNELING_OVERHEAD_MAX)) 949 error = EINVAL; 950 else 951 V_tcp_udp_tunneling_overhead = new; 952 } 953 return (error); 954 } 955 956 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, udp_tunneling_overhead, 957 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 958 &VNET_NAME(tcp_udp_tunneling_overhead), 959 0, &sysctl_net_inet_tcp_udp_tunneling_overhead_check, "IU", 960 "MSS reduction when using tcp over udp"); 961 962 /* 963 * Exports one (struct tcp_function_info) for each alias/name. 964 */ 965 static int 966 sysctl_net_inet_list_func_info(SYSCTL_HANDLER_ARGS) 967 { 968 int cnt, error; 969 struct tcp_function *f; 970 struct tcp_function_info tfi; 971 972 /* 973 * We don't allow writes. 974 */ 975 if (req->newptr != NULL) 976 return (EINVAL); 977 978 /* 979 * Wire the old buffer so we can directly copy the functions to 980 * user space without dropping the lock. 981 */ 982 if (req->oldptr != NULL) { 983 error = sysctl_wire_old_buffer(req, 0); 984 if (error) 985 return (error); 986 } 987 988 /* 989 * Walk the list and copy out matching entries. If INVARIANTS 990 * is compiled in, also walk the list to verify the length of 991 * the list matches what we have recorded. 992 */ 993 rw_rlock(&tcp_function_lock); 994 995 cnt = 0; 996 #ifndef INVARIANTS 997 if (req->oldptr == NULL) { 998 cnt = tcp_fb_cnt; 999 goto skip_loop; 1000 } 1001 #endif 1002 TAILQ_FOREACH(f, &t_functions, tf_next) { 1003 #ifdef INVARIANTS 1004 cnt++; 1005 #endif 1006 if (req->oldptr != NULL) { 1007 bzero(&tfi, sizeof(tfi)); 1008 tfi.tfi_refcnt = f->tf_fb->tfb_refcnt; 1009 tfi.tfi_id = f->tf_fb->tfb_id; 1010 (void)strlcpy(tfi.tfi_alias, f->tf_name, 1011 sizeof(tfi.tfi_alias)); 1012 (void)strlcpy(tfi.tfi_name, 1013 f->tf_fb->tfb_tcp_block_name, sizeof(tfi.tfi_name)); 1014 error = SYSCTL_OUT(req, &tfi, sizeof(tfi)); 1015 /* 1016 * Don't stop on error, as that is the 1017 * mechanism we use to accumulate length 1018 * information if the buffer was too short. 1019 */ 1020 } 1021 } 1022 KASSERT(cnt == tcp_fb_cnt, 1023 ("%s: cnt (%d) != tcp_fb_cnt (%d)", __func__, cnt, tcp_fb_cnt)); 1024 #ifndef INVARIANTS 1025 skip_loop: 1026 #endif 1027 rw_runlock(&tcp_function_lock); 1028 if (req->oldptr == NULL) 1029 error = SYSCTL_OUT(req, NULL, 1030 (cnt + 1) * sizeof(struct tcp_function_info)); 1031 1032 return (error); 1033 } 1034 1035 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, function_info, 1036 CTLTYPE_OPAQUE | CTLFLAG_SKIP | CTLFLAG_RD | CTLFLAG_MPSAFE, 1037 NULL, 0, sysctl_net_inet_list_func_info, "S,tcp_function_info", 1038 "List TCP function block name-to-ID mappings"); 1039 1040 /* 1041 * tfb_tcp_handoff_ok() function for the default stack. 1042 * Note that we'll basically try to take all comers. 1043 */ 1044 static int 1045 tcp_default_handoff_ok(struct tcpcb *tp) 1046 { 1047 1048 return (0); 1049 } 1050 1051 /* 1052 * tfb_tcp_fb_init() function for the default stack. 1053 * 1054 * This handles making sure we have appropriate timers set if you are 1055 * transitioning a socket that has some amount of setup done. 1056 * 1057 * The init() fuction from the default can *never* return non-zero i.e. 1058 * it is required to always succeed since it is the stack of last resort! 1059 */ 1060 static int 1061 tcp_default_fb_init(struct tcpcb *tp, void **ptr) 1062 { 1063 struct socket *so = tptosocket(tp); 1064 int rexmt; 1065 1066 INP_WLOCK_ASSERT(tptoinpcb(tp)); 1067 /* We don't use the pointer */ 1068 *ptr = NULL; 1069 1070 KASSERT(tp->t_state >= 0 && tp->t_state < TCPS_TIME_WAIT, 1071 ("%s: connection %p in unexpected state %d", __func__, tp, 1072 tp->t_state)); 1073 1074 /* Make sure we get no interesting mbuf queuing behavior */ 1075 /* All mbuf queue/ack compress flags should be off */ 1076 tcp_lro_features_off(tptoinpcb(tp)); 1077 1078 /* Cancel the GP measurement in progress */ 1079 tp->t_flags &= ~TF_GPUTINPROG; 1080 /* Validate the timers are not in usec, if they are convert */ 1081 tcp_change_time_units(tp, TCP_TMR_GRANULARITY_TICKS); 1082 if ((tp->t_state == TCPS_SYN_SENT) || 1083 (tp->t_state == TCPS_SYN_RECEIVED)) 1084 rexmt = tcp_rexmit_initial * tcp_backoff[tp->t_rxtshift]; 1085 else 1086 rexmt = TCP_REXMTVAL(tp) * tcp_backoff[tp->t_rxtshift]; 1087 if (tp->t_rxtshift == 0) 1088 tp->t_rxtcur = rexmt; 1089 else 1090 TCPT_RANGESET(tp->t_rxtcur, rexmt, tp->t_rttmin, TCPTV_REXMTMAX); 1091 1092 /* 1093 * Nothing to do for ESTABLISHED or LISTEN states. And, we don't 1094 * know what to do for unexpected states (which includes TIME_WAIT). 1095 */ 1096 if (tp->t_state <= TCPS_LISTEN || tp->t_state >= TCPS_TIME_WAIT) 1097 return (0); 1098 1099 /* 1100 * Make sure some kind of transmission timer is set if there is 1101 * outstanding data. 1102 */ 1103 if ((!TCPS_HAVEESTABLISHED(tp->t_state) || sbavail(&so->so_snd) || 1104 tp->snd_una != tp->snd_max) && !(tcp_timer_active(tp, TT_REXMT) || 1105 tcp_timer_active(tp, TT_PERSIST))) { 1106 /* 1107 * If the session has established and it looks like it should 1108 * be in the persist state, set the persist timer. Otherwise, 1109 * set the retransmit timer. 1110 */ 1111 if (TCPS_HAVEESTABLISHED(tp->t_state) && tp->snd_wnd == 0 && 1112 (int32_t)(tp->snd_nxt - tp->snd_una) < 1113 (int32_t)sbavail(&so->so_snd)) 1114 tcp_setpersist(tp); 1115 else 1116 tcp_timer_activate(tp, TT_REXMT, TP_RXTCUR(tp)); 1117 } 1118 1119 /* All non-embryonic sessions get a keepalive timer. */ 1120 if (!tcp_timer_active(tp, TT_KEEP)) 1121 tcp_timer_activate(tp, TT_KEEP, 1122 TCPS_HAVEESTABLISHED(tp->t_state) ? TP_KEEPIDLE(tp) : 1123 TP_KEEPINIT(tp)); 1124 1125 /* 1126 * Make sure critical variables are initialized 1127 * if transitioning while in Recovery. 1128 */ 1129 if IN_FASTRECOVERY(tp->t_flags) { 1130 if (tp->sackhint.recover_fs == 0) 1131 tp->sackhint.recover_fs = max(1, 1132 tp->snd_nxt - tp->snd_una); 1133 } 1134 1135 return (0); 1136 } 1137 1138 /* 1139 * tfb_tcp_fb_fini() function for the default stack. 1140 * 1141 * This changes state as necessary (or prudent) to prepare for another stack 1142 * to assume responsibility for the connection. 1143 */ 1144 static void 1145 tcp_default_fb_fini(struct tcpcb *tp, int tcb_is_purged) 1146 { 1147 1148 INP_WLOCK_ASSERT(tptoinpcb(tp)); 1149 1150 #ifdef TCP_BLACKBOX 1151 tcp_log_flowend(tp); 1152 #endif 1153 tp->t_acktime = 0; 1154 return; 1155 } 1156 1157 /* 1158 * Target size of TCP PCB hash tables. Must be a power of two. 1159 * 1160 * Note that this can be overridden by the kernel environment 1161 * variable net.inet.tcp.tcbhashsize 1162 */ 1163 #ifndef TCBHASHSIZE 1164 #define TCBHASHSIZE 0 1165 #endif 1166 1167 MALLOC_DEFINE(M_TCPLOG, "tcplog", "TCP address and flags print buffers"); 1168 MALLOC_DEFINE(M_TCPFUNCTIONS, "tcpfunc", "TCP function set memory"); 1169 1170 static struct mtx isn_mtx; 1171 1172 #define ISN_LOCK_INIT() mtx_init(&isn_mtx, "isn_mtx", NULL, MTX_DEF) 1173 #define ISN_LOCK() mtx_lock(&isn_mtx) 1174 #define ISN_UNLOCK() mtx_unlock(&isn_mtx) 1175 1176 INPCBSTORAGE_DEFINE(tcpcbstor, tcpcb, "tcpinp", "tcp_inpcb", "tcp", "tcphash"); 1177 1178 /* 1179 * Take a value and get the next power of 2 that doesn't overflow. 1180 * Used to size the tcp_inpcb hash buckets. 1181 */ 1182 static int 1183 maketcp_hashsize(int size) 1184 { 1185 int hashsize; 1186 1187 /* 1188 * auto tune. 1189 * get the next power of 2 higher than maxsockets. 1190 */ 1191 hashsize = 1 << fls(size); 1192 /* catch overflow, and just go one power of 2 smaller */ 1193 if (hashsize < size) { 1194 hashsize = 1 << (fls(size) - 1); 1195 } 1196 return (hashsize); 1197 } 1198 1199 static volatile int next_tcp_stack_id = 1; 1200 1201 /* 1202 * Register a TCP function block with the name provided in the names 1203 * array. (Note that this function does NOT automatically register 1204 * blk->tfb_tcp_block_name as a stack name. Therefore, you should 1205 * explicitly include blk->tfb_tcp_block_name in the list of names if 1206 * you wish to register the stack with that name.) 1207 * 1208 * Either all name registrations will succeed or all will fail. If 1209 * a name registration fails, the function will update the num_names 1210 * argument to point to the array index of the name that encountered 1211 * the failure. 1212 * 1213 * Returns 0 on success, or an error code on failure. 1214 */ 1215 int 1216 register_tcp_functions_as_names(struct tcp_function_block *blk, int wait, 1217 const char *names[], int *num_names) 1218 { 1219 struct tcp_function *n; 1220 struct tcp_function_set fs; 1221 int error, i; 1222 1223 KASSERT(names != NULL && *num_names > 0, 1224 ("%s: Called with 0-length name list", __func__)); 1225 KASSERT(names != NULL, ("%s: Called with NULL name list", __func__)); 1226 KASSERT(rw_initialized(&tcp_function_lock), 1227 ("%s: called too early", __func__)); 1228 1229 if ((blk->tfb_tcp_output == NULL) || 1230 (blk->tfb_tcp_do_segment == NULL) || 1231 (blk->tfb_tcp_ctloutput == NULL) || 1232 (strlen(blk->tfb_tcp_block_name) == 0)) { 1233 /* 1234 * These functions are required and you 1235 * need a name. 1236 */ 1237 *num_names = 0; 1238 return (EINVAL); 1239 } 1240 1241 if (blk->tfb_flags & TCP_FUNC_BEING_REMOVED) { 1242 *num_names = 0; 1243 return (EINVAL); 1244 } 1245 1246 refcount_init(&blk->tfb_refcnt, 0); 1247 blk->tfb_id = atomic_fetchadd_int(&next_tcp_stack_id, 1); 1248 for (i = 0; i < *num_names; i++) { 1249 n = malloc(sizeof(struct tcp_function), M_TCPFUNCTIONS, wait); 1250 if (n == NULL) { 1251 error = ENOMEM; 1252 goto cleanup; 1253 } 1254 n->tf_fb = blk; 1255 1256 (void)strlcpy(fs.function_set_name, names[i], 1257 sizeof(fs.function_set_name)); 1258 rw_wlock(&tcp_function_lock); 1259 if (find_tcp_functions_locked(&fs) != NULL) { 1260 /* Duplicate name space not allowed */ 1261 rw_wunlock(&tcp_function_lock); 1262 free(n, M_TCPFUNCTIONS); 1263 error = EALREADY; 1264 goto cleanup; 1265 } 1266 (void)strlcpy(n->tf_name, names[i], sizeof(n->tf_name)); 1267 TAILQ_INSERT_TAIL(&t_functions, n, tf_next); 1268 tcp_fb_cnt++; 1269 rw_wunlock(&tcp_function_lock); 1270 } 1271 return(0); 1272 1273 cleanup: 1274 /* 1275 * Deregister the names we just added. Because registration failed 1276 * for names[i], we don't need to deregister that name. 1277 */ 1278 *num_names = i; 1279 rw_wlock(&tcp_function_lock); 1280 while (--i >= 0) { 1281 TAILQ_FOREACH(n, &t_functions, tf_next) { 1282 if (!strncmp(n->tf_name, names[i], 1283 TCP_FUNCTION_NAME_LEN_MAX)) { 1284 TAILQ_REMOVE(&t_functions, n, tf_next); 1285 tcp_fb_cnt--; 1286 n->tf_fb = NULL; 1287 free(n, M_TCPFUNCTIONS); 1288 break; 1289 } 1290 } 1291 } 1292 rw_wunlock(&tcp_function_lock); 1293 return (error); 1294 } 1295 1296 /* 1297 * Register a TCP function block using the name provided in the name 1298 * argument. 1299 * 1300 * Returns 0 on success, or an error code on failure. 1301 */ 1302 int 1303 register_tcp_functions_as_name(struct tcp_function_block *blk, const char *name, 1304 int wait) 1305 { 1306 const char *name_list[1]; 1307 int num_names, rv; 1308 1309 num_names = 1; 1310 if (name != NULL) 1311 name_list[0] = name; 1312 else 1313 name_list[0] = blk->tfb_tcp_block_name; 1314 rv = register_tcp_functions_as_names(blk, wait, name_list, &num_names); 1315 return (rv); 1316 } 1317 1318 /* 1319 * Register a TCP function block using the name defined in 1320 * blk->tfb_tcp_block_name. 1321 * 1322 * Returns 0 on success, or an error code on failure. 1323 */ 1324 int 1325 register_tcp_functions(struct tcp_function_block *blk, int wait) 1326 { 1327 1328 return (register_tcp_functions_as_name(blk, NULL, wait)); 1329 } 1330 1331 /* 1332 * Deregister all names associated with a function block. This 1333 * functionally removes the function block from use within the system. 1334 * 1335 * When called with a true quiesce argument, mark the function block 1336 * as being removed so no more stacks will use it and determine 1337 * whether the removal would succeed. 1338 * 1339 * When called with a false quiesce argument, actually attempt the 1340 * removal. 1341 * 1342 * When called with a force argument, attempt to switch all TCBs to 1343 * use the default stack instead of returning EBUSY. 1344 * 1345 * Returns 0 on success (or if the removal would succeed), or an error 1346 * code on failure. 1347 */ 1348 int 1349 deregister_tcp_functions(struct tcp_function_block *blk, bool quiesce, 1350 bool force) 1351 { 1352 struct tcp_function *f; 1353 VNET_ITERATOR_DECL(vnet_iter); 1354 1355 if (blk == &tcp_def_funcblk) { 1356 /* You can't un-register the default */ 1357 return (EPERM); 1358 } 1359 rw_wlock(&tcp_function_lock); 1360 VNET_LIST_RLOCK_NOSLEEP(); 1361 VNET_FOREACH(vnet_iter) { 1362 CURVNET_SET(vnet_iter); 1363 if (blk == V_tcp_func_set_ptr) { 1364 /* You can't free the current default in some vnet. */ 1365 CURVNET_RESTORE(); 1366 VNET_LIST_RUNLOCK_NOSLEEP(); 1367 rw_wunlock(&tcp_function_lock); 1368 return (EBUSY); 1369 } 1370 CURVNET_RESTORE(); 1371 } 1372 VNET_LIST_RUNLOCK_NOSLEEP(); 1373 /* Mark the block so no more stacks can use it. */ 1374 blk->tfb_flags |= TCP_FUNC_BEING_REMOVED; 1375 /* 1376 * If TCBs are still attached to the stack, attempt to switch them 1377 * to the default stack. 1378 */ 1379 if (force && blk->tfb_refcnt) { 1380 struct inpcb *inp; 1381 struct tcpcb *tp; 1382 VNET_ITERATOR_DECL(vnet_iter); 1383 1384 rw_wunlock(&tcp_function_lock); 1385 1386 VNET_LIST_RLOCK(); 1387 VNET_FOREACH(vnet_iter) { 1388 CURVNET_SET(vnet_iter); 1389 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, 1390 INPLOOKUP_WLOCKPCB); 1391 1392 while ((inp = inp_next(&inpi)) != NULL) { 1393 tp = intotcpcb(inp); 1394 if (tp == NULL || tp->t_fb != blk) 1395 continue; 1396 tcp_switch_back_to_default(tp); 1397 } 1398 CURVNET_RESTORE(); 1399 } 1400 VNET_LIST_RUNLOCK(); 1401 1402 rw_wlock(&tcp_function_lock); 1403 } 1404 if (blk->tfb_refcnt) { 1405 /* TCBs still attached. */ 1406 rw_wunlock(&tcp_function_lock); 1407 return (EBUSY); 1408 } 1409 if (quiesce) { 1410 /* Skip removal. */ 1411 rw_wunlock(&tcp_function_lock); 1412 return (0); 1413 } 1414 /* Remove any function names that map to this function block. */ 1415 while (find_tcp_fb_locked(blk, &f) != NULL) { 1416 TAILQ_REMOVE(&t_functions, f, tf_next); 1417 tcp_fb_cnt--; 1418 f->tf_fb = NULL; 1419 free(f, M_TCPFUNCTIONS); 1420 } 1421 rw_wunlock(&tcp_function_lock); 1422 return (0); 1423 } 1424 1425 static void 1426 tcp_drain(void) 1427 { 1428 struct epoch_tracker et; 1429 VNET_ITERATOR_DECL(vnet_iter); 1430 1431 if (!do_tcpdrain) 1432 return; 1433 1434 NET_EPOCH_ENTER(et); 1435 VNET_LIST_RLOCK_NOSLEEP(); 1436 VNET_FOREACH(vnet_iter) { 1437 CURVNET_SET(vnet_iter); 1438 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, 1439 INPLOOKUP_WLOCKPCB); 1440 struct inpcb *inpb; 1441 struct tcpcb *tcpb; 1442 1443 /* 1444 * Walk the tcpbs, if existing, and flush the reassembly queue, 1445 * if there is one... 1446 * XXX: The "Net/3" implementation doesn't imply that the TCP 1447 * reassembly queue should be flushed, but in a situation 1448 * where we're really low on mbufs, this is potentially 1449 * useful. 1450 */ 1451 while ((inpb = inp_next(&inpi)) != NULL) { 1452 if ((tcpb = intotcpcb(inpb)) != NULL) { 1453 tcp_reass_flush(tcpb); 1454 tcp_clean_sackreport(tcpb); 1455 #ifdef TCP_BLACKBOX 1456 tcp_log_drain(tcpb); 1457 #endif 1458 #ifdef TCPPCAP 1459 if (tcp_pcap_aggressive_free) { 1460 /* Free the TCP PCAP queues. */ 1461 tcp_pcap_drain(&(tcpb->t_inpkts)); 1462 tcp_pcap_drain(&(tcpb->t_outpkts)); 1463 } 1464 #endif 1465 } 1466 } 1467 CURVNET_RESTORE(); 1468 } 1469 VNET_LIST_RUNLOCK_NOSLEEP(); 1470 NET_EPOCH_EXIT(et); 1471 } 1472 1473 static void 1474 tcp_vnet_init(void *arg __unused) 1475 { 1476 1477 #ifdef TCP_HHOOK 1478 if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN, 1479 &V_tcp_hhh[HHOOK_TCP_EST_IN], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0) 1480 printf("%s: WARNING: unable to register helper hook\n", __func__); 1481 if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT, 1482 &V_tcp_hhh[HHOOK_TCP_EST_OUT], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0) 1483 printf("%s: WARNING: unable to register helper hook\n", __func__); 1484 #endif 1485 #ifdef STATS 1486 if (tcp_stats_init()) 1487 printf("%s: WARNING: unable to initialise TCP stats\n", 1488 __func__); 1489 #endif 1490 in_pcbinfo_init(&V_tcbinfo, &tcpcbstor, tcp_tcbhashsize, 1491 tcp_tcbhashsize); 1492 1493 syncache_init(); 1494 tcp_hc_init(); 1495 1496 TUNABLE_INT_FETCH("net.inet.tcp.sack.enable", &V_tcp_do_sack); 1497 V_sack_hole_zone = uma_zcreate("sackhole", sizeof(struct sackhole), 1498 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 1499 1500 tcp_fastopen_init(); 1501 1502 COUNTER_ARRAY_ALLOC(V_tcps_states, TCP_NSTATES, M_WAITOK); 1503 VNET_PCPUSTAT_ALLOC(tcpstat, M_WAITOK); 1504 1505 V_tcp_msl = TCPTV_MSL; 1506 } 1507 VNET_SYSINIT(tcp_vnet_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, 1508 tcp_vnet_init, NULL); 1509 1510 static void 1511 tcp_init(void *arg __unused) 1512 { 1513 const char *tcbhash_tuneable; 1514 int hashsize; 1515 1516 tcp_reass_global_init(); 1517 1518 /* XXX virtualize those below? */ 1519 tcp_delacktime = TCPTV_DELACK; 1520 tcp_keepinit = TCPTV_KEEP_INIT; 1521 tcp_keepidle = TCPTV_KEEP_IDLE; 1522 tcp_keepintvl = TCPTV_KEEPINTVL; 1523 tcp_maxpersistidle = TCPTV_KEEP_IDLE; 1524 tcp_rexmit_initial = TCPTV_RTOBASE; 1525 if (tcp_rexmit_initial < 1) 1526 tcp_rexmit_initial = 1; 1527 tcp_rexmit_min = TCPTV_MIN; 1528 if (tcp_rexmit_min < 1) 1529 tcp_rexmit_min = 1; 1530 tcp_persmin = TCPTV_PERSMIN; 1531 tcp_persmax = TCPTV_PERSMAX; 1532 tcp_rexmit_slop = TCPTV_CPU_VAR; 1533 tcp_finwait2_timeout = TCPTV_FINWAIT2_TIMEOUT; 1534 1535 /* Setup the tcp function block list */ 1536 TAILQ_INIT(&t_functions); 1537 rw_init(&tcp_function_lock, "tcp_func_lock"); 1538 register_tcp_functions(&tcp_def_funcblk, M_WAITOK); 1539 sx_init(&tcpoudp_lock, "TCP over UDP configuration"); 1540 #ifdef TCP_BLACKBOX 1541 /* Initialize the TCP logging data. */ 1542 tcp_log_init(); 1543 #endif 1544 arc4rand(&V_ts_offset_secret, sizeof(V_ts_offset_secret), 0); 1545 1546 if (tcp_soreceive_stream) { 1547 #ifdef INET 1548 tcp_protosw.pr_soreceive = soreceive_stream; 1549 #endif 1550 #ifdef INET6 1551 tcp6_protosw.pr_soreceive = soreceive_stream; 1552 #endif /* INET6 */ 1553 } 1554 1555 #ifdef INET6 1556 max_protohdr_grow(sizeof(struct ip6_hdr) + sizeof(struct tcphdr)); 1557 #else /* INET6 */ 1558 max_protohdr_grow(sizeof(struct tcpiphdr)); 1559 #endif /* INET6 */ 1560 1561 ISN_LOCK_INIT(); 1562 EVENTHANDLER_REGISTER(shutdown_pre_sync, tcp_fini, NULL, 1563 SHUTDOWN_PRI_DEFAULT); 1564 EVENTHANDLER_REGISTER(vm_lowmem, tcp_drain, NULL, LOWMEM_PRI_DEFAULT); 1565 EVENTHANDLER_REGISTER(mbuf_lowmem, tcp_drain, NULL, LOWMEM_PRI_DEFAULT); 1566 1567 tcp_inp_lro_direct_queue = counter_u64_alloc(M_WAITOK); 1568 tcp_inp_lro_wokeup_queue = counter_u64_alloc(M_WAITOK); 1569 tcp_inp_lro_compressed = counter_u64_alloc(M_WAITOK); 1570 tcp_inp_lro_locks_taken = counter_u64_alloc(M_WAITOK); 1571 tcp_extra_mbuf = counter_u64_alloc(M_WAITOK); 1572 tcp_would_have_but = counter_u64_alloc(M_WAITOK); 1573 tcp_comp_total = counter_u64_alloc(M_WAITOK); 1574 tcp_uncomp_total = counter_u64_alloc(M_WAITOK); 1575 tcp_bad_csums = counter_u64_alloc(M_WAITOK); 1576 tcp_pacing_failures = counter_u64_alloc(M_WAITOK); 1577 #ifdef TCPPCAP 1578 tcp_pcap_init(); 1579 #endif 1580 1581 hashsize = TCBHASHSIZE; 1582 tcbhash_tuneable = "net.inet.tcp.tcbhashsize"; 1583 TUNABLE_INT_FETCH(tcbhash_tuneable, &hashsize); 1584 if (hashsize == 0) { 1585 /* 1586 * Auto tune the hash size based on maxsockets. 1587 * A perfect hash would have a 1:1 mapping 1588 * (hashsize = maxsockets) however it's been 1589 * suggested that O(2) average is better. 1590 */ 1591 hashsize = maketcp_hashsize(maxsockets / 4); 1592 /* 1593 * Our historical default is 512, 1594 * do not autotune lower than this. 1595 */ 1596 if (hashsize < 512) 1597 hashsize = 512; 1598 if (bootverbose) 1599 printf("%s: %s auto tuned to %d\n", __func__, 1600 tcbhash_tuneable, hashsize); 1601 } 1602 /* 1603 * We require a hashsize to be a power of two. 1604 * Previously if it was not a power of two we would just reset it 1605 * back to 512, which could be a nasty surprise if you did not notice 1606 * the error message. 1607 * Instead what we do is clip it to the closest power of two lower 1608 * than the specified hash value. 1609 */ 1610 if (!powerof2(hashsize)) { 1611 int oldhashsize = hashsize; 1612 1613 hashsize = maketcp_hashsize(hashsize); 1614 /* prevent absurdly low value */ 1615 if (hashsize < 16) 1616 hashsize = 16; 1617 printf("%s: WARNING: TCB hash size not a power of 2, " 1618 "clipped from %d to %d.\n", __func__, oldhashsize, 1619 hashsize); 1620 } 1621 tcp_tcbhashsize = hashsize; 1622 1623 #ifdef INET 1624 IPPROTO_REGISTER(IPPROTO_TCP, tcp_input, tcp_ctlinput); 1625 #endif 1626 #ifdef INET6 1627 IP6PROTO_REGISTER(IPPROTO_TCP, tcp6_input, tcp6_ctlinput); 1628 #endif 1629 } 1630 SYSINIT(tcp_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, tcp_init, NULL); 1631 1632 #ifdef VIMAGE 1633 static void 1634 tcp_destroy(void *unused __unused) 1635 { 1636 int n; 1637 #ifdef TCP_HHOOK 1638 int error; 1639 #endif 1640 1641 /* 1642 * All our processes are gone, all our sockets should be cleaned 1643 * up, which means, we should be past the tcp_discardcb() calls. 1644 * Sleep to let all tcpcb timers really disappear and cleanup. 1645 */ 1646 for (;;) { 1647 INP_INFO_WLOCK(&V_tcbinfo); 1648 n = V_tcbinfo.ipi_count; 1649 INP_INFO_WUNLOCK(&V_tcbinfo); 1650 if (n == 0) 1651 break; 1652 pause("tcpdes", hz / 10); 1653 } 1654 tcp_hc_destroy(); 1655 syncache_destroy(); 1656 in_pcbinfo_destroy(&V_tcbinfo); 1657 /* tcp_discardcb() clears the sack_holes up. */ 1658 uma_zdestroy(V_sack_hole_zone); 1659 1660 /* 1661 * Cannot free the zone until all tcpcbs are released as we attach 1662 * the allocations to them. 1663 */ 1664 tcp_fastopen_destroy(); 1665 1666 COUNTER_ARRAY_FREE(V_tcps_states, TCP_NSTATES); 1667 VNET_PCPUSTAT_FREE(tcpstat); 1668 1669 #ifdef TCP_HHOOK 1670 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_IN]); 1671 if (error != 0) { 1672 printf("%s: WARNING: unable to deregister helper hook " 1673 "type=%d, id=%d: error %d returned\n", __func__, 1674 HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN, error); 1675 } 1676 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_OUT]); 1677 if (error != 0) { 1678 printf("%s: WARNING: unable to deregister helper hook " 1679 "type=%d, id=%d: error %d returned\n", __func__, 1680 HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT, error); 1681 } 1682 #endif 1683 } 1684 VNET_SYSUNINIT(tcp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, tcp_destroy, NULL); 1685 #endif 1686 1687 void 1688 tcp_fini(void *xtp) 1689 { 1690 1691 } 1692 1693 /* 1694 * Fill in the IP and TCP headers for an outgoing packet, given the tcpcb. 1695 * tcp_template used to store this data in mbufs, but we now recopy it out 1696 * of the tcpcb each time to conserve mbufs. 1697 */ 1698 void 1699 tcpip_fillheaders(struct inpcb *inp, uint16_t port, void *ip_ptr, void *tcp_ptr) 1700 { 1701 struct tcphdr *th = (struct tcphdr *)tcp_ptr; 1702 1703 INP_WLOCK_ASSERT(inp); 1704 1705 #ifdef INET6 1706 if ((inp->inp_vflag & INP_IPV6) != 0) { 1707 struct ip6_hdr *ip6; 1708 1709 ip6 = (struct ip6_hdr *)ip_ptr; 1710 ip6->ip6_flow = (ip6->ip6_flow & ~IPV6_FLOWINFO_MASK) | 1711 (inp->inp_flow & IPV6_FLOWINFO_MASK); 1712 ip6->ip6_vfc = (ip6->ip6_vfc & ~IPV6_VERSION_MASK) | 1713 (IPV6_VERSION & IPV6_VERSION_MASK); 1714 if (port == 0) 1715 ip6->ip6_nxt = IPPROTO_TCP; 1716 else 1717 ip6->ip6_nxt = IPPROTO_UDP; 1718 ip6->ip6_plen = htons(sizeof(struct tcphdr)); 1719 ip6->ip6_src = inp->in6p_laddr; 1720 ip6->ip6_dst = inp->in6p_faddr; 1721 } 1722 #endif /* INET6 */ 1723 #if defined(INET6) && defined(INET) 1724 else 1725 #endif 1726 #ifdef INET 1727 { 1728 struct ip *ip; 1729 1730 ip = (struct ip *)ip_ptr; 1731 ip->ip_v = IPVERSION; 1732 ip->ip_hl = 5; 1733 ip->ip_tos = inp->inp_ip_tos; 1734 ip->ip_len = 0; 1735 ip->ip_id = 0; 1736 ip->ip_off = 0; 1737 ip->ip_ttl = inp->inp_ip_ttl; 1738 ip->ip_sum = 0; 1739 if (port == 0) 1740 ip->ip_p = IPPROTO_TCP; 1741 else 1742 ip->ip_p = IPPROTO_UDP; 1743 ip->ip_src = inp->inp_laddr; 1744 ip->ip_dst = inp->inp_faddr; 1745 } 1746 #endif /* INET */ 1747 th->th_sport = inp->inp_lport; 1748 th->th_dport = inp->inp_fport; 1749 th->th_seq = 0; 1750 th->th_ack = 0; 1751 th->th_off = 5; 1752 tcp_set_flags(th, 0); 1753 th->th_win = 0; 1754 th->th_urp = 0; 1755 th->th_sum = 0; /* in_pseudo() is called later for ipv4 */ 1756 } 1757 1758 /* 1759 * Create template to be used to send tcp packets on a connection. 1760 * Allocates an mbuf and fills in a skeletal tcp/ip header. The only 1761 * use for this function is in keepalives, which use tcp_respond. 1762 */ 1763 struct tcptemp * 1764 tcpip_maketemplate(struct inpcb *inp) 1765 { 1766 struct tcptemp *t; 1767 1768 t = malloc(sizeof(*t), M_TEMP, M_NOWAIT); 1769 if (t == NULL) 1770 return (NULL); 1771 tcpip_fillheaders(inp, 0, (void *)&t->tt_ipgen, (void *)&t->tt_t); 1772 return (t); 1773 } 1774 1775 /* 1776 * Send a single message to the TCP at address specified by 1777 * the given TCP/IP header. If m == NULL, then we make a copy 1778 * of the tcpiphdr at th and send directly to the addressed host. 1779 * This is used to force keep alive messages out using the TCP 1780 * template for a connection. If flags are given then we send 1781 * a message back to the TCP which originated the segment th, 1782 * and discard the mbuf containing it and any other attached mbufs. 1783 * 1784 * In any case the ack and sequence number of the transmitted 1785 * segment are as specified by the parameters. 1786 * 1787 * NOTE: If m != NULL, then th must point to *inside* the mbuf. 1788 */ 1789 void 1790 tcp_respond(struct tcpcb *tp, void *ipgen, struct tcphdr *th, struct mbuf *m, 1791 tcp_seq ack, tcp_seq seq, uint16_t flags) 1792 { 1793 struct tcpopt to; 1794 struct inpcb *inp; 1795 struct ip *ip; 1796 struct mbuf *optm; 1797 struct udphdr *uh = NULL; 1798 struct tcphdr *nth; 1799 struct tcp_log_buffer *lgb; 1800 u_char *optp; 1801 #ifdef INET6 1802 struct ip6_hdr *ip6; 1803 int isipv6; 1804 #endif /* INET6 */ 1805 int optlen, tlen, win, ulen; 1806 int ect = 0; 1807 bool incl_opts; 1808 uint16_t port; 1809 int output_ret; 1810 #ifdef INVARIANTS 1811 int thflags = tcp_get_flags(th); 1812 #endif 1813 1814 KASSERT(tp != NULL || m != NULL, ("tcp_respond: tp and m both NULL")); 1815 NET_EPOCH_ASSERT(); 1816 1817 #ifdef INET6 1818 isipv6 = ((struct ip *)ipgen)->ip_v == (IPV6_VERSION >> 4); 1819 ip6 = ipgen; 1820 #endif /* INET6 */ 1821 ip = ipgen; 1822 1823 if (tp != NULL) { 1824 inp = tptoinpcb(tp); 1825 INP_LOCK_ASSERT(inp); 1826 } else 1827 inp = NULL; 1828 1829 if (m != NULL) { 1830 #ifdef INET6 1831 if (isipv6 && ip6 && (ip6->ip6_nxt == IPPROTO_UDP)) 1832 port = m->m_pkthdr.tcp_tun_port; 1833 else 1834 #endif 1835 if (ip && (ip->ip_p == IPPROTO_UDP)) 1836 port = m->m_pkthdr.tcp_tun_port; 1837 else 1838 port = 0; 1839 } else 1840 port = tp->t_port; 1841 1842 incl_opts = false; 1843 win = 0; 1844 if (tp != NULL) { 1845 if (!(flags & TH_RST)) { 1846 win = sbspace(&inp->inp_socket->so_rcv); 1847 if (win > TCP_MAXWIN << tp->rcv_scale) 1848 win = TCP_MAXWIN << tp->rcv_scale; 1849 } 1850 if ((tp->t_flags & TF_NOOPT) == 0) 1851 incl_opts = true; 1852 } 1853 if (m == NULL) { 1854 m = m_gethdr(M_NOWAIT, MT_DATA); 1855 if (m == NULL) 1856 return; 1857 m->m_data += max_linkhdr; 1858 #ifdef INET6 1859 if (isipv6) { 1860 bcopy((caddr_t)ip6, mtod(m, caddr_t), 1861 sizeof(struct ip6_hdr)); 1862 ip6 = mtod(m, struct ip6_hdr *); 1863 nth = (struct tcphdr *)(ip6 + 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 } else 1872 #endif /* INET6 */ 1873 { 1874 bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip)); 1875 ip = mtod(m, struct ip *); 1876 nth = (struct tcphdr *)(ip + 1); 1877 if (port) { 1878 /* Insert a UDP header */ 1879 uh = (struct udphdr *)nth; 1880 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1881 uh->uh_dport = port; 1882 nth = (struct tcphdr *)(uh + 1); 1883 } 1884 } 1885 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr)); 1886 flags = TH_ACK; 1887 } else if ((!M_WRITABLE(m)) || (port != 0)) { 1888 struct mbuf *n; 1889 1890 /* Can't reuse 'm', allocate a new mbuf. */ 1891 n = m_gethdr(M_NOWAIT, MT_DATA); 1892 if (n == NULL) { 1893 m_freem(m); 1894 return; 1895 } 1896 1897 if (!m_dup_pkthdr(n, m, M_NOWAIT)) { 1898 m_freem(m); 1899 m_freem(n); 1900 return; 1901 } 1902 1903 n->m_data += max_linkhdr; 1904 /* m_len is set later */ 1905 #define xchg(a,b,type) { type t; t=a; a=b; b=t; } 1906 #ifdef INET6 1907 if (isipv6) { 1908 bcopy((caddr_t)ip6, mtod(n, caddr_t), 1909 sizeof(struct ip6_hdr)); 1910 ip6 = mtod(n, struct ip6_hdr *); 1911 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); 1912 nth = (struct tcphdr *)(ip6 + 1); 1913 if (port) { 1914 /* Insert a UDP header */ 1915 uh = (struct udphdr *)nth; 1916 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1917 uh->uh_dport = port; 1918 nth = (struct tcphdr *)(uh + 1); 1919 } 1920 } else 1921 #endif /* INET6 */ 1922 { 1923 bcopy((caddr_t)ip, mtod(n, caddr_t), sizeof(struct ip)); 1924 ip = mtod(n, struct ip *); 1925 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t); 1926 nth = (struct tcphdr *)(ip + 1); 1927 if (port) { 1928 /* Insert a UDP header */ 1929 uh = (struct udphdr *)nth; 1930 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1931 uh->uh_dport = port; 1932 nth = (struct tcphdr *)(uh + 1); 1933 } 1934 } 1935 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr)); 1936 xchg(nth->th_dport, nth->th_sport, uint16_t); 1937 th = nth; 1938 m_freem(m); 1939 m = n; 1940 } else { 1941 /* 1942 * reuse the mbuf. 1943 * XXX MRT We inherit the FIB, which is lucky. 1944 */ 1945 m_freem(m->m_next); 1946 m->m_next = NULL; 1947 m->m_data = (caddr_t)ipgen; 1948 /* clear any receive flags for proper bpf timestamping */ 1949 m->m_flags &= ~(M_TSTMP | M_TSTMP_LRO); 1950 /* m_len is set later */ 1951 #ifdef INET6 1952 if (isipv6) { 1953 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); 1954 nth = (struct tcphdr *)(ip6 + 1); 1955 } else 1956 #endif /* INET6 */ 1957 { 1958 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t); 1959 nth = (struct tcphdr *)(ip + 1); 1960 } 1961 if (th != nth) { 1962 /* 1963 * this is usually a case when an extension header 1964 * exists between the IPv6 header and the 1965 * TCP header. 1966 */ 1967 nth->th_sport = th->th_sport; 1968 nth->th_dport = th->th_dport; 1969 } 1970 xchg(nth->th_dport, nth->th_sport, uint16_t); 1971 #undef xchg 1972 } 1973 tlen = 0; 1974 #ifdef INET6 1975 if (isipv6) 1976 tlen = sizeof (struct ip6_hdr) + sizeof (struct tcphdr); 1977 #endif 1978 #if defined(INET) && defined(INET6) 1979 else 1980 #endif 1981 #ifdef INET 1982 tlen = sizeof (struct tcpiphdr); 1983 #endif 1984 if (port) 1985 tlen += sizeof (struct udphdr); 1986 #ifdef INVARIANTS 1987 m->m_len = 0; 1988 KASSERT(M_TRAILINGSPACE(m) >= tlen, 1989 ("Not enough trailing space for message (m=%p, need=%d, have=%ld)", 1990 m, tlen, (long)M_TRAILINGSPACE(m))); 1991 #endif 1992 m->m_len = tlen; 1993 to.to_flags = 0; 1994 if (incl_opts) { 1995 ect = tcp_ecn_output_established(tp, &flags, 0, false); 1996 /* Make sure we have room. */ 1997 if (M_TRAILINGSPACE(m) < TCP_MAXOLEN) { 1998 m->m_next = m_get(M_NOWAIT, MT_DATA); 1999 if (m->m_next) { 2000 optp = mtod(m->m_next, u_char *); 2001 optm = m->m_next; 2002 } else 2003 incl_opts = false; 2004 } else { 2005 optp = (u_char *) (nth + 1); 2006 optm = m; 2007 } 2008 } 2009 if (incl_opts) { 2010 /* Timestamps. */ 2011 if (tp->t_flags & TF_RCVD_TSTMP) { 2012 to.to_tsval = tcp_ts_getticks() + tp->ts_offset; 2013 to.to_tsecr = tp->ts_recent; 2014 to.to_flags |= TOF_TS; 2015 } 2016 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 2017 /* TCP-MD5 (RFC2385). */ 2018 if (tp->t_flags & TF_SIGNATURE) 2019 to.to_flags |= TOF_SIGNATURE; 2020 #endif 2021 /* Add the options. */ 2022 tlen += optlen = tcp_addoptions(&to, optp); 2023 2024 /* Update m_len in the correct mbuf. */ 2025 optm->m_len += optlen; 2026 } else 2027 optlen = 0; 2028 #ifdef INET6 2029 if (isipv6) { 2030 if (uh) { 2031 ulen = tlen - sizeof(struct ip6_hdr); 2032 uh->uh_ulen = htons(ulen); 2033 } 2034 ip6->ip6_flow = htonl(ect << IPV6_FLOWLABEL_LEN); 2035 ip6->ip6_vfc = IPV6_VERSION; 2036 if (port) 2037 ip6->ip6_nxt = IPPROTO_UDP; 2038 else 2039 ip6->ip6_nxt = IPPROTO_TCP; 2040 ip6->ip6_plen = htons(tlen - sizeof(*ip6)); 2041 } 2042 #endif 2043 #if defined(INET) && defined(INET6) 2044 else 2045 #endif 2046 #ifdef INET 2047 { 2048 if (uh) { 2049 ulen = tlen - sizeof(struct ip); 2050 uh->uh_ulen = htons(ulen); 2051 } 2052 ip->ip_tos = ect; 2053 ip->ip_len = htons(tlen); 2054 ip->ip_ttl = V_ip_defttl; 2055 if (port) { 2056 ip->ip_p = IPPROTO_UDP; 2057 } else { 2058 ip->ip_p = IPPROTO_TCP; 2059 } 2060 if (V_path_mtu_discovery) 2061 ip->ip_off |= htons(IP_DF); 2062 } 2063 #endif 2064 m->m_pkthdr.len = tlen; 2065 m->m_pkthdr.rcvif = NULL; 2066 #ifdef MAC 2067 if (inp != NULL) { 2068 /* 2069 * Packet is associated with a socket, so allow the 2070 * label of the response to reflect the socket label. 2071 */ 2072 INP_LOCK_ASSERT(inp); 2073 mac_inpcb_create_mbuf(inp, m); 2074 } else { 2075 /* 2076 * Packet is not associated with a socket, so possibly 2077 * update the label in place. 2078 */ 2079 mac_netinet_tcp_reply(m); 2080 } 2081 #endif 2082 nth->th_seq = htonl(seq); 2083 nth->th_ack = htonl(ack); 2084 nth->th_off = (sizeof (struct tcphdr) + optlen) >> 2; 2085 tcp_set_flags(nth, flags); 2086 if (tp && (flags & TH_RST)) { 2087 /* Log the reset */ 2088 tcp_log_end_status(tp, TCP_EI_STATUS_SERVER_RST); 2089 } 2090 if (tp != NULL) 2091 nth->th_win = htons((u_short) (win >> tp->rcv_scale)); 2092 else 2093 nth->th_win = htons((u_short)win); 2094 nth->th_urp = 0; 2095 2096 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 2097 if (to.to_flags & TOF_SIGNATURE) { 2098 if (!TCPMD5_ENABLED() || 2099 TCPMD5_OUTPUT(m, nth, to.to_signature) != 0) { 2100 m_freem(m); 2101 return; 2102 } 2103 } 2104 #endif 2105 2106 #ifdef INET6 2107 if (isipv6) { 2108 if (port) { 2109 m->m_pkthdr.csum_flags = CSUM_UDP_IPV6; 2110 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 2111 uh->uh_sum = in6_cksum_pseudo(ip6, ulen, IPPROTO_UDP, 0); 2112 nth->th_sum = 0; 2113 } else { 2114 m->m_pkthdr.csum_flags = CSUM_TCP_IPV6; 2115 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); 2116 nth->th_sum = in6_cksum_pseudo(ip6, 2117 tlen - sizeof(struct ip6_hdr), IPPROTO_TCP, 0); 2118 } 2119 ip6->ip6_hlim = in6_selecthlim(inp, NULL); 2120 } 2121 #endif /* INET6 */ 2122 #if defined(INET6) && defined(INET) 2123 else 2124 #endif 2125 #ifdef INET 2126 { 2127 if (port) { 2128 uh->uh_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, 2129 htons(ulen + IPPROTO_UDP)); 2130 m->m_pkthdr.csum_flags = CSUM_UDP; 2131 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 2132 nth->th_sum = 0; 2133 } else { 2134 m->m_pkthdr.csum_flags = CSUM_TCP; 2135 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); 2136 nth->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, 2137 htons((u_short)(tlen - sizeof(struct ip) + ip->ip_p))); 2138 } 2139 } 2140 #endif /* INET */ 2141 TCP_PROBE3(debug__output, tp, th, m); 2142 if (flags & TH_RST) 2143 TCP_PROBE5(accept__refused, NULL, NULL, m, tp, nth); 2144 lgb = NULL; 2145 if ((tp != NULL) && tcp_bblogging_on(tp)) { 2146 if (INP_WLOCKED(inp)) { 2147 union tcp_log_stackspecific log; 2148 struct timeval tv; 2149 2150 memset(&log.u_bbr, 0, sizeof(log.u_bbr)); 2151 log.u_bbr.inhpts = inp->inp_in_hpts; 2152 log.u_bbr.flex8 = 4; 2153 log.u_bbr.pkts_out = tp->t_maxseg; 2154 log.u_bbr.timeStamp = tcp_get_usecs(&tv); 2155 log.u_bbr.delivered = 0; 2156 lgb = tcp_log_event(tp, nth, NULL, NULL, TCP_LOG_OUT, 2157 ERRNO_UNK, 0, &log, false, NULL, NULL, 0, &tv); 2158 } else { 2159 /* 2160 * We can not log the packet, since we only own the 2161 * read lock, but a write lock is needed. The read lock 2162 * is not upgraded to a write lock, since only getting 2163 * the read lock was done intentionally to improve the 2164 * handling of SYN flooding attacks. 2165 * This happens only for pure SYN segments received in 2166 * the initial CLOSED state, or received in a more 2167 * advanced state than listen and the UDP encapsulation 2168 * port is unexpected. 2169 * The incoming SYN segments do not really belong to 2170 * the TCP connection and the handling does not change 2171 * the state of the TCP connection. Therefore, the 2172 * sending of the RST segments is not logged. Please 2173 * note that also the incoming SYN segments are not 2174 * logged. 2175 * 2176 * The following code ensures that the above description 2177 * is and stays correct. 2178 */ 2179 KASSERT((thflags & (TH_ACK|TH_SYN)) == TH_SYN && 2180 (tp->t_state == TCPS_CLOSED || 2181 (tp->t_state > TCPS_LISTEN && tp->t_port != port)), 2182 ("%s: Logging of TCP segment with flags 0x%b and " 2183 "UDP encapsulation port %u skipped in state %s", 2184 __func__, thflags, PRINT_TH_FLAGS, 2185 ntohs(port), tcpstates[tp->t_state])); 2186 } 2187 } 2188 2189 if (flags & TH_ACK) 2190 TCPSTAT_INC(tcps_sndacks); 2191 else if (flags & (TH_SYN|TH_FIN|TH_RST)) 2192 TCPSTAT_INC(tcps_sndctrl); 2193 TCPSTAT_INC(tcps_sndtotal); 2194 2195 #ifdef INET6 2196 if (isipv6) { 2197 TCP_PROBE5(send, NULL, tp, ip6, tp, nth); 2198 output_ret = ip6_output(m, NULL, NULL, 0, NULL, NULL, inp); 2199 } 2200 #endif /* INET6 */ 2201 #if defined(INET) && defined(INET6) 2202 else 2203 #endif 2204 #ifdef INET 2205 { 2206 TCP_PROBE5(send, NULL, tp, ip, tp, nth); 2207 output_ret = ip_output(m, NULL, NULL, 0, NULL, inp); 2208 } 2209 #endif 2210 if (lgb != NULL) 2211 lgb->tlb_errno = output_ret; 2212 } 2213 2214 /* 2215 * Create a new TCP control block, making an empty reassembly queue and hooking 2216 * it to the argument protocol control block. The `inp' parameter must have 2217 * come from the zone allocator set up by tcpcbstor declaration. 2218 */ 2219 struct tcpcb * 2220 tcp_newtcpcb(struct inpcb *inp) 2221 { 2222 struct tcpcb *tp = intotcpcb(inp); 2223 #ifdef INET6 2224 int isipv6 = (inp->inp_vflag & INP_IPV6) != 0; 2225 #endif /* INET6 */ 2226 2227 /* 2228 * Historically allocation was done with M_ZERO. There is a lot of 2229 * code that rely on that. For now take safe approach and zero whole 2230 * tcpcb. This definitely can be optimized. 2231 */ 2232 bzero(&tp->t_start_zero, t_zero_size); 2233 2234 /* Initialise cc_var struct for this tcpcb. */ 2235 tp->t_ccv.type = IPPROTO_TCP; 2236 tp->t_ccv.ccvc.tcp = tp; 2237 rw_rlock(&tcp_function_lock); 2238 tp->t_fb = V_tcp_func_set_ptr; 2239 refcount_acquire(&tp->t_fb->tfb_refcnt); 2240 rw_runlock(&tcp_function_lock); 2241 /* 2242 * Use the current system default CC algorithm. 2243 */ 2244 cc_attach(tp, CC_DEFAULT_ALGO()); 2245 2246 if (CC_ALGO(tp)->cb_init != NULL) 2247 if (CC_ALGO(tp)->cb_init(&tp->t_ccv, NULL) > 0) { 2248 cc_detach(tp); 2249 if (tp->t_fb->tfb_tcp_fb_fini) 2250 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); 2251 refcount_release(&tp->t_fb->tfb_refcnt); 2252 return (NULL); 2253 } 2254 2255 #ifdef TCP_HHOOK 2256 if (khelp_init_osd(HELPER_CLASS_TCP, &tp->t_osd)) { 2257 if (tp->t_fb->tfb_tcp_fb_fini) 2258 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); 2259 refcount_release(&tp->t_fb->tfb_refcnt); 2260 return (NULL); 2261 } 2262 #endif 2263 2264 TAILQ_INIT(&tp->t_segq); 2265 STAILQ_INIT(&tp->t_inqueue); 2266 tp->t_maxseg = 2267 #ifdef INET6 2268 isipv6 ? V_tcp_v6mssdflt : 2269 #endif /* INET6 */ 2270 V_tcp_mssdflt; 2271 2272 /* All mbuf queue/ack compress flags should be off */ 2273 tcp_lro_features_off(tptoinpcb(tp)); 2274 2275 callout_init_rw(&tp->t_callout, &inp->inp_lock, CALLOUT_RETURNUNLOCKED); 2276 for (int i = 0; i < TT_N; i++) 2277 tp->t_timers[i] = SBT_MAX; 2278 2279 switch (V_tcp_do_rfc1323) { 2280 case 0: 2281 break; 2282 default: 2283 case 1: 2284 tp->t_flags = (TF_REQ_SCALE|TF_REQ_TSTMP); 2285 break; 2286 case 2: 2287 tp->t_flags = TF_REQ_SCALE; 2288 break; 2289 case 3: 2290 tp->t_flags = TF_REQ_TSTMP; 2291 break; 2292 } 2293 if (V_tcp_do_sack) 2294 tp->t_flags |= TF_SACK_PERMIT; 2295 TAILQ_INIT(&tp->snd_holes); 2296 2297 /* 2298 * Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no 2299 * rtt estimate. Set rttvar so that srtt + 4 * rttvar gives 2300 * reasonable initial retransmit time. 2301 */ 2302 tp->t_srtt = TCPTV_SRTTBASE; 2303 tp->t_rttvar = ((tcp_rexmit_initial - TCPTV_SRTTBASE) << TCP_RTTVAR_SHIFT) / 4; 2304 tp->t_rttmin = tcp_rexmit_min; 2305 tp->t_rxtcur = tcp_rexmit_initial; 2306 tp->snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT; 2307 tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT; 2308 tp->t_rcvtime = ticks; 2309 /* We always start with ticks granularity */ 2310 tp->t_tmr_granularity = TCP_TMR_GRANULARITY_TICKS; 2311 /* 2312 * IPv4 TTL initialization is necessary for an IPv6 socket as well, 2313 * because the socket may be bound to an IPv6 wildcard address, 2314 * which may match an IPv4-mapped IPv6 address. 2315 */ 2316 inp->inp_ip_ttl = V_ip_defttl; 2317 #ifdef TCPHPTS 2318 /* 2319 * If using hpts lets drop a random number in so 2320 * not all new connections fall on the same CPU. 2321 */ 2322 inp->inp_hpts_cpu = hpts_random_cpu(inp); 2323 #endif 2324 #ifdef TCPPCAP 2325 /* 2326 * Init the TCP PCAP queues. 2327 */ 2328 tcp_pcap_tcpcb_init(tp); 2329 #endif 2330 #ifdef TCP_BLACKBOX 2331 /* Initialize the per-TCPCB log data. */ 2332 tcp_log_tcpcbinit(tp); 2333 #endif 2334 tp->t_pacing_rate = -1; 2335 if (tp->t_fb->tfb_tcp_fb_init) { 2336 if ((*tp->t_fb->tfb_tcp_fb_init)(tp, &tp->t_fb_ptr)) { 2337 refcount_release(&tp->t_fb->tfb_refcnt); 2338 return (NULL); 2339 } 2340 } 2341 #ifdef STATS 2342 if (V_tcp_perconn_stats_enable == 1) 2343 tp->t_stats = stats_blob_alloc(V_tcp_perconn_stats_dflt_tpl, 0); 2344 #endif 2345 if (V_tcp_do_lrd) 2346 tp->t_flags |= TF_LRD; 2347 2348 return (tp); 2349 } 2350 2351 /* 2352 * Drop a TCP connection, reporting 2353 * the specified error. If connection is synchronized, 2354 * then send a RST to peer. 2355 */ 2356 struct tcpcb * 2357 tcp_drop(struct tcpcb *tp, int errno) 2358 { 2359 struct socket *so = tptosocket(tp); 2360 2361 NET_EPOCH_ASSERT(); 2362 INP_WLOCK_ASSERT(tptoinpcb(tp)); 2363 2364 if (TCPS_HAVERCVDSYN(tp->t_state)) { 2365 tcp_state_change(tp, TCPS_CLOSED); 2366 /* Don't use tcp_output() here due to possible recursion. */ 2367 (void)tcp_output_nodrop(tp); 2368 TCPSTAT_INC(tcps_drops); 2369 } else 2370 TCPSTAT_INC(tcps_conndrops); 2371 if (errno == ETIMEDOUT && tp->t_softerror) 2372 errno = tp->t_softerror; 2373 so->so_error = errno; 2374 return (tcp_close(tp)); 2375 } 2376 2377 void 2378 tcp_discardcb(struct tcpcb *tp) 2379 { 2380 struct inpcb *inp = tptoinpcb(tp); 2381 struct socket *so = tptosocket(tp); 2382 #ifdef INET6 2383 bool isipv6 = (inp->inp_vflag & INP_IPV6) != 0; 2384 #endif 2385 2386 INP_WLOCK_ASSERT(inp); 2387 2388 tcp_timer_stop(tp); 2389 if (tp->t_fb->tfb_tcp_timer_stop_all) { 2390 tp->t_fb->tfb_tcp_timer_stop_all(tp); 2391 } 2392 2393 /* free the reassembly queue, if any */ 2394 tcp_reass_flush(tp); 2395 2396 #ifdef TCP_OFFLOAD 2397 /* Disconnect offload device, if any. */ 2398 if (tp->t_flags & TF_TOE) 2399 tcp_offload_detach(tp); 2400 #endif 2401 2402 tcp_free_sackholes(tp); 2403 2404 #ifdef TCPPCAP 2405 /* Free the TCP PCAP queues. */ 2406 tcp_pcap_drain(&(tp->t_inpkts)); 2407 tcp_pcap_drain(&(tp->t_outpkts)); 2408 #endif 2409 2410 /* Allow the CC algorithm to clean up after itself. */ 2411 if (CC_ALGO(tp)->cb_destroy != NULL) 2412 CC_ALGO(tp)->cb_destroy(&tp->t_ccv); 2413 CC_DATA(tp) = NULL; 2414 /* Detach from the CC algorithm */ 2415 cc_detach(tp); 2416 2417 #ifdef TCP_HHOOK 2418 khelp_destroy_osd(&tp->t_osd); 2419 #endif 2420 #ifdef STATS 2421 stats_blob_destroy(tp->t_stats); 2422 #endif 2423 2424 CC_ALGO(tp) = NULL; 2425 2426 TCPSTATES_DEC(tp->t_state); 2427 2428 if (tp->t_fb->tfb_tcp_fb_fini) 2429 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); 2430 #ifdef TCP_BLACKBOX 2431 tcp_log_tcpcbfini(tp); 2432 #endif 2433 MPASS(STAILQ_EMPTY(&tp->t_inqueue)); 2434 2435 /* 2436 * If we got enough samples through the srtt filter, 2437 * save the rtt and rttvar in the routing entry. 2438 * 'Enough' is arbitrarily defined as 4 rtt samples. 2439 * 4 samples is enough for the srtt filter to converge 2440 * to within enough % of the correct value; fewer samples 2441 * and we could save a bogus rtt. The danger is not high 2442 * as tcp quickly recovers from everything. 2443 * XXX: Works very well but needs some more statistics! 2444 * 2445 * XXXRRS: Updating must be after the stack fini() since 2446 * that may be converting some internal representation of 2447 * say srtt etc into the general one used by other stacks. 2448 * Lets also at least protect against the so being NULL 2449 * as RW stated below. 2450 */ 2451 if ((tp->t_rttupdated >= 4) && (so != NULL)) { 2452 struct hc_metrics_lite metrics; 2453 uint32_t ssthresh; 2454 2455 bzero(&metrics, sizeof(metrics)); 2456 /* 2457 * Update the ssthresh always when the conditions below 2458 * are satisfied. This gives us better new start value 2459 * for the congestion avoidance for new connections. 2460 * ssthresh is only set if packet loss occurred on a session. 2461 * 2462 * XXXRW: 'so' may be NULL here, and/or socket buffer may be 2463 * being torn down. Ideally this code would not use 'so'. 2464 */ 2465 ssthresh = tp->snd_ssthresh; 2466 if (ssthresh != 0 && ssthresh < so->so_snd.sb_hiwat / 2) { 2467 /* 2468 * convert the limit from user data bytes to 2469 * packets then to packet data bytes. 2470 */ 2471 ssthresh = (ssthresh + tp->t_maxseg / 2) / tp->t_maxseg; 2472 if (ssthresh < 2) 2473 ssthresh = 2; 2474 ssthresh *= (tp->t_maxseg + 2475 #ifdef INET6 2476 (isipv6 ? sizeof (struct ip6_hdr) + 2477 sizeof (struct tcphdr) : 2478 #endif 2479 sizeof (struct tcpiphdr) 2480 #ifdef INET6 2481 ) 2482 #endif 2483 ); 2484 } else 2485 ssthresh = 0; 2486 metrics.rmx_ssthresh = ssthresh; 2487 2488 metrics.rmx_rtt = tp->t_srtt; 2489 metrics.rmx_rttvar = tp->t_rttvar; 2490 metrics.rmx_cwnd = tp->snd_cwnd; 2491 metrics.rmx_sendpipe = 0; 2492 metrics.rmx_recvpipe = 0; 2493 2494 tcp_hc_update(&inp->inp_inc, &metrics); 2495 } 2496 2497 refcount_release(&tp->t_fb->tfb_refcnt); 2498 } 2499 2500 /* 2501 * Attempt to close a TCP control block, marking it as dropped, and freeing 2502 * the socket if we hold the only reference. 2503 */ 2504 struct tcpcb * 2505 tcp_close(struct tcpcb *tp) 2506 { 2507 struct inpcb *inp = tptoinpcb(tp); 2508 struct socket *so = tptosocket(tp); 2509 2510 INP_WLOCK_ASSERT(inp); 2511 2512 #ifdef TCP_OFFLOAD 2513 if (tp->t_state == TCPS_LISTEN) 2514 tcp_offload_listen_stop(tp); 2515 #endif 2516 /* 2517 * This releases the TFO pending counter resource for TFO listen 2518 * sockets as well as passively-created TFO sockets that transition 2519 * from SYN_RECEIVED to CLOSED. 2520 */ 2521 if (tp->t_tfo_pending) { 2522 tcp_fastopen_decrement_counter(tp->t_tfo_pending); 2523 tp->t_tfo_pending = NULL; 2524 } 2525 #ifdef TCPHPTS 2526 tcp_hpts_remove(inp); 2527 #endif 2528 in_pcbdrop(inp); 2529 TCPSTAT_INC(tcps_closed); 2530 if (tp->t_state != TCPS_CLOSED) 2531 tcp_state_change(tp, TCPS_CLOSED); 2532 KASSERT(inp->inp_socket != NULL, ("tcp_close: inp_socket NULL")); 2533 soisdisconnected(so); 2534 if (inp->inp_flags & INP_SOCKREF) { 2535 inp->inp_flags &= ~INP_SOCKREF; 2536 INP_WUNLOCK(inp); 2537 sorele(so); 2538 return (NULL); 2539 } 2540 return (tp); 2541 } 2542 2543 /* 2544 * Notify a tcp user of an asynchronous error; 2545 * store error as soft error, but wake up user 2546 * (for now, won't do anything until can select for soft error). 2547 * 2548 * Do not wake up user since there currently is no mechanism for 2549 * reporting soft errors (yet - a kqueue filter may be added). 2550 */ 2551 static struct inpcb * 2552 tcp_notify(struct inpcb *inp, int error) 2553 { 2554 struct tcpcb *tp; 2555 2556 INP_WLOCK_ASSERT(inp); 2557 2558 tp = intotcpcb(inp); 2559 KASSERT(tp != NULL, ("tcp_notify: tp == NULL")); 2560 2561 /* 2562 * Ignore some errors if we are hooked up. 2563 * If connection hasn't completed, has retransmitted several times, 2564 * and receives a second error, give up now. This is better 2565 * than waiting a long time to establish a connection that 2566 * can never complete. 2567 */ 2568 if (tp->t_state == TCPS_ESTABLISHED && 2569 (error == EHOSTUNREACH || error == ENETUNREACH || 2570 error == EHOSTDOWN)) { 2571 if (inp->inp_route.ro_nh) { 2572 NH_FREE(inp->inp_route.ro_nh); 2573 inp->inp_route.ro_nh = (struct nhop_object *)NULL; 2574 } 2575 return (inp); 2576 } else if (tp->t_state < TCPS_ESTABLISHED && tp->t_rxtshift > 3 && 2577 tp->t_softerror) { 2578 tp = tcp_drop(tp, error); 2579 if (tp != NULL) 2580 return (inp); 2581 else 2582 return (NULL); 2583 } else { 2584 tp->t_softerror = error; 2585 return (inp); 2586 } 2587 #if 0 2588 wakeup( &so->so_timeo); 2589 sorwakeup(so); 2590 sowwakeup(so); 2591 #endif 2592 } 2593 2594 static int 2595 tcp_pcblist(SYSCTL_HANDLER_ARGS) 2596 { 2597 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, 2598 INPLOOKUP_RLOCKPCB); 2599 struct xinpgen xig; 2600 struct inpcb *inp; 2601 int error; 2602 2603 if (req->newptr != NULL) 2604 return (EPERM); 2605 2606 if (req->oldptr == NULL) { 2607 int n; 2608 2609 n = V_tcbinfo.ipi_count + 2610 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); 2611 n += imax(n / 8, 10); 2612 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xtcpcb); 2613 return (0); 2614 } 2615 2616 if ((error = sysctl_wire_old_buffer(req, 0)) != 0) 2617 return (error); 2618 2619 bzero(&xig, sizeof(xig)); 2620 xig.xig_len = sizeof xig; 2621 xig.xig_count = V_tcbinfo.ipi_count + 2622 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); 2623 xig.xig_gen = V_tcbinfo.ipi_gencnt; 2624 xig.xig_sogen = so_gencnt; 2625 error = SYSCTL_OUT(req, &xig, sizeof xig); 2626 if (error) 2627 return (error); 2628 2629 error = syncache_pcblist(req); 2630 if (error) 2631 return (error); 2632 2633 while ((inp = inp_next(&inpi)) != NULL) { 2634 if (inp->inp_gencnt <= xig.xig_gen && 2635 cr_canseeinpcb(req->td->td_ucred, inp) == 0) { 2636 struct xtcpcb xt; 2637 2638 tcp_inptoxtp(inp, &xt); 2639 error = SYSCTL_OUT(req, &xt, sizeof xt); 2640 if (error) { 2641 INP_RUNLOCK(inp); 2642 break; 2643 } else 2644 continue; 2645 } 2646 } 2647 2648 if (!error) { 2649 /* 2650 * Give the user an updated idea of our state. 2651 * If the generation differs from what we told 2652 * her before, she knows that something happened 2653 * while we were processing this request, and it 2654 * might be necessary to retry. 2655 */ 2656 xig.xig_gen = V_tcbinfo.ipi_gencnt; 2657 xig.xig_sogen = so_gencnt; 2658 xig.xig_count = V_tcbinfo.ipi_count + 2659 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); 2660 error = SYSCTL_OUT(req, &xig, sizeof xig); 2661 } 2662 2663 return (error); 2664 } 2665 2666 SYSCTL_PROC(_net_inet_tcp, TCPCTL_PCBLIST, pcblist, 2667 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_NEEDGIANT, 2668 NULL, 0, tcp_pcblist, "S,xtcpcb", 2669 "List of active TCP connections"); 2670 2671 #ifdef INET 2672 static int 2673 tcp_getcred(SYSCTL_HANDLER_ARGS) 2674 { 2675 struct xucred xuc; 2676 struct sockaddr_in addrs[2]; 2677 struct epoch_tracker et; 2678 struct inpcb *inp; 2679 int error; 2680 2681 error = priv_check(req->td, PRIV_NETINET_GETCRED); 2682 if (error) 2683 return (error); 2684 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 2685 if (error) 2686 return (error); 2687 NET_EPOCH_ENTER(et); 2688 inp = in_pcblookup(&V_tcbinfo, addrs[1].sin_addr, addrs[1].sin_port, 2689 addrs[0].sin_addr, addrs[0].sin_port, INPLOOKUP_RLOCKPCB, NULL); 2690 NET_EPOCH_EXIT(et); 2691 if (inp != NULL) { 2692 if (error == 0) 2693 error = cr_canseeinpcb(req->td->td_ucred, inp); 2694 if (error == 0) 2695 cru2x(inp->inp_cred, &xuc); 2696 INP_RUNLOCK(inp); 2697 } else 2698 error = ENOENT; 2699 if (error == 0) 2700 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 2701 return (error); 2702 } 2703 2704 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, getcred, 2705 CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_NEEDGIANT, 2706 0, 0, tcp_getcred, "S,xucred", 2707 "Get the xucred of a TCP connection"); 2708 #endif /* INET */ 2709 2710 #ifdef INET6 2711 static int 2712 tcp6_getcred(SYSCTL_HANDLER_ARGS) 2713 { 2714 struct epoch_tracker et; 2715 struct xucred xuc; 2716 struct sockaddr_in6 addrs[2]; 2717 struct inpcb *inp; 2718 int error; 2719 #ifdef INET 2720 int mapped = 0; 2721 #endif 2722 2723 error = priv_check(req->td, PRIV_NETINET_GETCRED); 2724 if (error) 2725 return (error); 2726 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 2727 if (error) 2728 return (error); 2729 if ((error = sa6_embedscope(&addrs[0], V_ip6_use_defzone)) != 0 || 2730 (error = sa6_embedscope(&addrs[1], V_ip6_use_defzone)) != 0) { 2731 return (error); 2732 } 2733 if (IN6_IS_ADDR_V4MAPPED(&addrs[0].sin6_addr)) { 2734 #ifdef INET 2735 if (IN6_IS_ADDR_V4MAPPED(&addrs[1].sin6_addr)) 2736 mapped = 1; 2737 else 2738 #endif 2739 return (EINVAL); 2740 } 2741 2742 NET_EPOCH_ENTER(et); 2743 #ifdef INET 2744 if (mapped == 1) 2745 inp = in_pcblookup(&V_tcbinfo, 2746 *(struct in_addr *)&addrs[1].sin6_addr.s6_addr[12], 2747 addrs[1].sin6_port, 2748 *(struct in_addr *)&addrs[0].sin6_addr.s6_addr[12], 2749 addrs[0].sin6_port, INPLOOKUP_RLOCKPCB, NULL); 2750 else 2751 #endif 2752 inp = in6_pcblookup(&V_tcbinfo, 2753 &addrs[1].sin6_addr, addrs[1].sin6_port, 2754 &addrs[0].sin6_addr, addrs[0].sin6_port, 2755 INPLOOKUP_RLOCKPCB, NULL); 2756 NET_EPOCH_EXIT(et); 2757 if (inp != NULL) { 2758 if (error == 0) 2759 error = cr_canseeinpcb(req->td->td_ucred, inp); 2760 if (error == 0) 2761 cru2x(inp->inp_cred, &xuc); 2762 INP_RUNLOCK(inp); 2763 } else 2764 error = ENOENT; 2765 if (error == 0) 2766 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 2767 return (error); 2768 } 2769 2770 SYSCTL_PROC(_net_inet6_tcp6, OID_AUTO, getcred, 2771 CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_NEEDGIANT, 2772 0, 0, tcp6_getcred, "S,xucred", 2773 "Get the xucred of a TCP6 connection"); 2774 #endif /* INET6 */ 2775 2776 #ifdef INET 2777 /* Path MTU to try next when a fragmentation-needed message is received. */ 2778 static inline int 2779 tcp_next_pmtu(const struct icmp *icp, const struct ip *ip) 2780 { 2781 int mtu = ntohs(icp->icmp_nextmtu); 2782 2783 /* If no alternative MTU was proposed, try the next smaller one. */ 2784 if (!mtu) 2785 mtu = ip_next_mtu(ntohs(ip->ip_len), 1); 2786 if (mtu < V_tcp_minmss + sizeof(struct tcpiphdr)) 2787 mtu = V_tcp_minmss + sizeof(struct tcpiphdr); 2788 2789 return (mtu); 2790 } 2791 2792 static void 2793 tcp_ctlinput_with_port(struct icmp *icp, uint16_t port) 2794 { 2795 struct ip *ip; 2796 struct tcphdr *th; 2797 struct inpcb *inp; 2798 struct tcpcb *tp; 2799 struct inpcb *(*notify)(struct inpcb *, int); 2800 struct in_conninfo inc; 2801 tcp_seq icmp_tcp_seq; 2802 int errno, mtu; 2803 2804 errno = icmp_errmap(icp); 2805 switch (errno) { 2806 case 0: 2807 return; 2808 case EMSGSIZE: 2809 notify = tcp_mtudisc_notify; 2810 break; 2811 case ECONNREFUSED: 2812 if (V_icmp_may_rst) 2813 notify = tcp_drop_syn_sent; 2814 else 2815 notify = tcp_notify; 2816 break; 2817 case EHOSTUNREACH: 2818 if (V_icmp_may_rst && icp->icmp_type == ICMP_TIMXCEED) 2819 notify = tcp_drop_syn_sent; 2820 else 2821 notify = tcp_notify; 2822 break; 2823 default: 2824 notify = tcp_notify; 2825 } 2826 2827 ip = &icp->icmp_ip; 2828 th = (struct tcphdr *)((caddr_t)ip + (ip->ip_hl << 2)); 2829 icmp_tcp_seq = th->th_seq; 2830 inp = in_pcblookup(&V_tcbinfo, ip->ip_dst, th->th_dport, ip->ip_src, 2831 th->th_sport, INPLOOKUP_WLOCKPCB, NULL); 2832 if (inp != NULL) { 2833 tp = intotcpcb(inp); 2834 #ifdef TCP_OFFLOAD 2835 if (tp->t_flags & TF_TOE && errno == EMSGSIZE) { 2836 /* 2837 * MTU discovery for offloaded connections. Let 2838 * the TOE driver verify seq# and process it. 2839 */ 2840 mtu = tcp_next_pmtu(icp, ip); 2841 tcp_offload_pmtu_update(tp, icmp_tcp_seq, mtu); 2842 goto out; 2843 } 2844 #endif 2845 if (tp->t_port != port) 2846 goto out; 2847 if (SEQ_GEQ(ntohl(icmp_tcp_seq), tp->snd_una) && 2848 SEQ_LT(ntohl(icmp_tcp_seq), tp->snd_max)) { 2849 if (errno == EMSGSIZE) { 2850 /* 2851 * MTU discovery: we got a needfrag and 2852 * will potentially try a lower MTU. 2853 */ 2854 mtu = tcp_next_pmtu(icp, ip); 2855 2856 /* 2857 * Only process the offered MTU if it 2858 * is smaller than the current one. 2859 */ 2860 if (mtu < tp->t_maxseg + 2861 sizeof(struct tcpiphdr)) { 2862 bzero(&inc, sizeof(inc)); 2863 inc.inc_faddr = ip->ip_dst; 2864 inc.inc_fibnum = 2865 inp->inp_inc.inc_fibnum; 2866 tcp_hc_updatemtu(&inc, mtu); 2867 inp = tcp_mtudisc(inp, mtu); 2868 } 2869 } else 2870 inp = (*notify)(inp, errno); 2871 } 2872 } else { 2873 bzero(&inc, sizeof(inc)); 2874 inc.inc_fport = th->th_dport; 2875 inc.inc_lport = th->th_sport; 2876 inc.inc_faddr = ip->ip_dst; 2877 inc.inc_laddr = ip->ip_src; 2878 syncache_unreach(&inc, icmp_tcp_seq, port); 2879 } 2880 out: 2881 if (inp != NULL) 2882 INP_WUNLOCK(inp); 2883 } 2884 2885 static void 2886 tcp_ctlinput(struct icmp *icmp) 2887 { 2888 tcp_ctlinput_with_port(icmp, htons(0)); 2889 } 2890 2891 static void 2892 tcp_ctlinput_viaudp(udp_tun_icmp_param_t param) 2893 { 2894 /* Its a tunneled TCP over UDP icmp */ 2895 struct icmp *icmp = param.icmp; 2896 struct ip *outer_ip, *inner_ip; 2897 struct udphdr *udp; 2898 struct tcphdr *th, ttemp; 2899 int i_hlen, o_len; 2900 uint16_t port; 2901 2902 outer_ip = (struct ip *)((caddr_t)icmp - sizeof(struct ip)); 2903 inner_ip = &icmp->icmp_ip; 2904 i_hlen = inner_ip->ip_hl << 2; 2905 o_len = ntohs(outer_ip->ip_len); 2906 if (o_len < 2907 (sizeof(struct ip) + 8 + i_hlen + sizeof(struct udphdr) + offsetof(struct tcphdr, th_ack))) { 2908 /* Not enough data present */ 2909 return; 2910 } 2911 /* Ok lets strip out the inner udphdr header by copying up on top of it the tcp hdr */ 2912 udp = (struct udphdr *)(((caddr_t)inner_ip) + i_hlen); 2913 if (ntohs(udp->uh_sport) != V_tcp_udp_tunneling_port) { 2914 return; 2915 } 2916 port = udp->uh_dport; 2917 th = (struct tcphdr *)(udp + 1); 2918 memcpy(&ttemp, th, sizeof(struct tcphdr)); 2919 memcpy(udp, &ttemp, sizeof(struct tcphdr)); 2920 /* Now adjust down the size of the outer IP header */ 2921 o_len -= sizeof(struct udphdr); 2922 outer_ip->ip_len = htons(o_len); 2923 /* Now call in to the normal handling code */ 2924 tcp_ctlinput_with_port(icmp, port); 2925 } 2926 #endif /* INET */ 2927 2928 #ifdef INET6 2929 static inline int 2930 tcp6_next_pmtu(const struct icmp6_hdr *icmp6) 2931 { 2932 int mtu = ntohl(icmp6->icmp6_mtu); 2933 2934 /* 2935 * If no alternative MTU was proposed, or the proposed MTU was too 2936 * small, set to the min. 2937 */ 2938 if (mtu < IPV6_MMTU) 2939 mtu = IPV6_MMTU - 8; /* XXXNP: what is the adjustment for? */ 2940 return (mtu); 2941 } 2942 2943 static void 2944 tcp6_ctlinput_with_port(struct ip6ctlparam *ip6cp, uint16_t port) 2945 { 2946 struct in6_addr *dst; 2947 struct inpcb *(*notify)(struct inpcb *, int); 2948 struct ip6_hdr *ip6; 2949 struct mbuf *m; 2950 struct inpcb *inp; 2951 struct tcpcb *tp; 2952 struct icmp6_hdr *icmp6; 2953 struct in_conninfo inc; 2954 struct tcp_ports { 2955 uint16_t th_sport; 2956 uint16_t th_dport; 2957 } t_ports; 2958 tcp_seq icmp_tcp_seq; 2959 unsigned int mtu; 2960 unsigned int off; 2961 int errno; 2962 2963 icmp6 = ip6cp->ip6c_icmp6; 2964 m = ip6cp->ip6c_m; 2965 ip6 = ip6cp->ip6c_ip6; 2966 off = ip6cp->ip6c_off; 2967 dst = &ip6cp->ip6c_finaldst->sin6_addr; 2968 2969 errno = icmp6_errmap(icmp6); 2970 switch (errno) { 2971 case 0: 2972 return; 2973 case EMSGSIZE: 2974 notify = tcp_mtudisc_notify; 2975 break; 2976 case ECONNREFUSED: 2977 if (V_icmp_may_rst) 2978 notify = tcp_drop_syn_sent; 2979 else 2980 notify = tcp_notify; 2981 break; 2982 case EHOSTUNREACH: 2983 /* 2984 * There are only four ICMPs that may reset connection: 2985 * - administratively prohibited 2986 * - port unreachable 2987 * - time exceeded in transit 2988 * - unknown next header 2989 */ 2990 if (V_icmp_may_rst && 2991 ((icmp6->icmp6_type == ICMP6_DST_UNREACH && 2992 (icmp6->icmp6_code == ICMP6_DST_UNREACH_ADMIN || 2993 icmp6->icmp6_code == ICMP6_DST_UNREACH_NOPORT)) || 2994 (icmp6->icmp6_type == ICMP6_TIME_EXCEEDED && 2995 icmp6->icmp6_code == ICMP6_TIME_EXCEED_TRANSIT) || 2996 (icmp6->icmp6_type == ICMP6_PARAM_PROB && 2997 icmp6->icmp6_code == ICMP6_PARAMPROB_NEXTHEADER))) 2998 notify = tcp_drop_syn_sent; 2999 else 3000 notify = tcp_notify; 3001 break; 3002 default: 3003 notify = tcp_notify; 3004 } 3005 3006 /* Check if we can safely get the ports from the tcp hdr */ 3007 if (m == NULL || 3008 (m->m_pkthdr.len < 3009 (int32_t) (off + sizeof(struct tcp_ports)))) { 3010 return; 3011 } 3012 bzero(&t_ports, sizeof(struct tcp_ports)); 3013 m_copydata(m, off, sizeof(struct tcp_ports), (caddr_t)&t_ports); 3014 inp = in6_pcblookup(&V_tcbinfo, &ip6->ip6_dst, t_ports.th_dport, 3015 &ip6->ip6_src, t_ports.th_sport, INPLOOKUP_WLOCKPCB, NULL); 3016 off += sizeof(struct tcp_ports); 3017 if (m->m_pkthdr.len < (int32_t) (off + sizeof(tcp_seq))) { 3018 goto out; 3019 } 3020 m_copydata(m, off, sizeof(tcp_seq), (caddr_t)&icmp_tcp_seq); 3021 if (inp != NULL) { 3022 tp = intotcpcb(inp); 3023 #ifdef TCP_OFFLOAD 3024 if (tp->t_flags & TF_TOE && errno == EMSGSIZE) { 3025 /* MTU discovery for offloaded connections. */ 3026 mtu = tcp6_next_pmtu(icmp6); 3027 tcp_offload_pmtu_update(tp, icmp_tcp_seq, mtu); 3028 goto out; 3029 } 3030 #endif 3031 if (tp->t_port != port) 3032 goto out; 3033 if (SEQ_GEQ(ntohl(icmp_tcp_seq), tp->snd_una) && 3034 SEQ_LT(ntohl(icmp_tcp_seq), tp->snd_max)) { 3035 if (errno == EMSGSIZE) { 3036 /* 3037 * MTU discovery: 3038 * If we got a needfrag set the MTU 3039 * in the route to the suggested new 3040 * value (if given) and then notify. 3041 */ 3042 mtu = tcp6_next_pmtu(icmp6); 3043 3044 bzero(&inc, sizeof(inc)); 3045 inc.inc_fibnum = M_GETFIB(m); 3046 inc.inc_flags |= INC_ISIPV6; 3047 inc.inc6_faddr = *dst; 3048 if (in6_setscope(&inc.inc6_faddr, 3049 m->m_pkthdr.rcvif, NULL)) 3050 goto out; 3051 /* 3052 * Only process the offered MTU if it 3053 * is smaller than the current one. 3054 */ 3055 if (mtu < tp->t_maxseg + 3056 sizeof (struct tcphdr) + 3057 sizeof (struct ip6_hdr)) { 3058 tcp_hc_updatemtu(&inc, mtu); 3059 tcp_mtudisc(inp, mtu); 3060 ICMP6STAT_INC(icp6s_pmtuchg); 3061 } 3062 } else 3063 inp = (*notify)(inp, errno); 3064 } 3065 } else { 3066 bzero(&inc, sizeof(inc)); 3067 inc.inc_fibnum = M_GETFIB(m); 3068 inc.inc_flags |= INC_ISIPV6; 3069 inc.inc_fport = t_ports.th_dport; 3070 inc.inc_lport = t_ports.th_sport; 3071 inc.inc6_faddr = *dst; 3072 inc.inc6_laddr = ip6->ip6_src; 3073 syncache_unreach(&inc, icmp_tcp_seq, port); 3074 } 3075 out: 3076 if (inp != NULL) 3077 INP_WUNLOCK(inp); 3078 } 3079 3080 static void 3081 tcp6_ctlinput(struct ip6ctlparam *ctl) 3082 { 3083 tcp6_ctlinput_with_port(ctl, htons(0)); 3084 } 3085 3086 static void 3087 tcp6_ctlinput_viaudp(udp_tun_icmp_param_t param) 3088 { 3089 struct ip6ctlparam *ip6cp = param.ip6cp; 3090 struct mbuf *m; 3091 struct udphdr *udp; 3092 uint16_t port; 3093 3094 m = m_pulldown(ip6cp->ip6c_m, ip6cp->ip6c_off, sizeof(struct udphdr), NULL); 3095 if (m == NULL) { 3096 return; 3097 } 3098 udp = mtod(m, struct udphdr *); 3099 if (ntohs(udp->uh_sport) != V_tcp_udp_tunneling_port) { 3100 return; 3101 } 3102 port = udp->uh_dport; 3103 m_adj(m, sizeof(struct udphdr)); 3104 if ((m->m_flags & M_PKTHDR) == 0) { 3105 ip6cp->ip6c_m->m_pkthdr.len -= sizeof(struct udphdr); 3106 } 3107 /* Now call in to the normal handling code */ 3108 tcp6_ctlinput_with_port(ip6cp, port); 3109 } 3110 3111 #endif /* INET6 */ 3112 3113 static uint32_t 3114 tcp_keyed_hash(struct in_conninfo *inc, u_char *key, u_int len) 3115 { 3116 SIPHASH_CTX ctx; 3117 uint32_t hash[2]; 3118 3119 KASSERT(len >= SIPHASH_KEY_LENGTH, 3120 ("%s: keylen %u too short ", __func__, len)); 3121 SipHash24_Init(&ctx); 3122 SipHash_SetKey(&ctx, (uint8_t *)key); 3123 SipHash_Update(&ctx, &inc->inc_fport, sizeof(uint16_t)); 3124 SipHash_Update(&ctx, &inc->inc_lport, sizeof(uint16_t)); 3125 switch (inc->inc_flags & INC_ISIPV6) { 3126 #ifdef INET 3127 case 0: 3128 SipHash_Update(&ctx, &inc->inc_faddr, sizeof(struct in_addr)); 3129 SipHash_Update(&ctx, &inc->inc_laddr, sizeof(struct in_addr)); 3130 break; 3131 #endif 3132 #ifdef INET6 3133 case INC_ISIPV6: 3134 SipHash_Update(&ctx, &inc->inc6_faddr, sizeof(struct in6_addr)); 3135 SipHash_Update(&ctx, &inc->inc6_laddr, sizeof(struct in6_addr)); 3136 break; 3137 #endif 3138 } 3139 SipHash_Final((uint8_t *)hash, &ctx); 3140 3141 return (hash[0] ^ hash[1]); 3142 } 3143 3144 uint32_t 3145 tcp_new_ts_offset(struct in_conninfo *inc) 3146 { 3147 struct in_conninfo inc_store, *local_inc; 3148 3149 if (!V_tcp_ts_offset_per_conn) { 3150 memcpy(&inc_store, inc, sizeof(struct in_conninfo)); 3151 inc_store.inc_lport = 0; 3152 inc_store.inc_fport = 0; 3153 local_inc = &inc_store; 3154 } else { 3155 local_inc = inc; 3156 } 3157 return (tcp_keyed_hash(local_inc, V_ts_offset_secret, 3158 sizeof(V_ts_offset_secret))); 3159 } 3160 3161 /* 3162 * Following is where TCP initial sequence number generation occurs. 3163 * 3164 * There are two places where we must use initial sequence numbers: 3165 * 1. In SYN-ACK packets. 3166 * 2. In SYN packets. 3167 * 3168 * All ISNs for SYN-ACK packets are generated by the syncache. See 3169 * tcp_syncache.c for details. 3170 * 3171 * The ISNs in SYN packets must be monotonic; TIME_WAIT recycling 3172 * depends on this property. In addition, these ISNs should be 3173 * unguessable so as to prevent connection hijacking. To satisfy 3174 * the requirements of this situation, the algorithm outlined in 3175 * RFC 1948 is used, with only small modifications. 3176 * 3177 * Implementation details: 3178 * 3179 * Time is based off the system timer, and is corrected so that it 3180 * increases by one megabyte per second. This allows for proper 3181 * recycling on high speed LANs while still leaving over an hour 3182 * before rollover. 3183 * 3184 * As reading the *exact* system time is too expensive to be done 3185 * whenever setting up a TCP connection, we increment the time 3186 * offset in two ways. First, a small random positive increment 3187 * is added to isn_offset for each connection that is set up. 3188 * Second, the function tcp_isn_tick fires once per clock tick 3189 * and increments isn_offset as necessary so that sequence numbers 3190 * are incremented at approximately ISN_BYTES_PER_SECOND. The 3191 * random positive increments serve only to ensure that the same 3192 * exact sequence number is never sent out twice (as could otherwise 3193 * happen when a port is recycled in less than the system tick 3194 * interval.) 3195 * 3196 * net.inet.tcp.isn_reseed_interval controls the number of seconds 3197 * between seeding of isn_secret. This is normally set to zero, 3198 * as reseeding should not be necessary. 3199 * 3200 * Locking of the global variables isn_secret, isn_last_reseed, isn_offset, 3201 * isn_offset_old, and isn_ctx is performed using the ISN lock. In 3202 * general, this means holding an exclusive (write) lock. 3203 */ 3204 3205 #define ISN_BYTES_PER_SECOND 1048576 3206 #define ISN_STATIC_INCREMENT 4096 3207 #define ISN_RANDOM_INCREMENT (4096 - 1) 3208 #define ISN_SECRET_LENGTH SIPHASH_KEY_LENGTH 3209 3210 VNET_DEFINE_STATIC(u_char, isn_secret[ISN_SECRET_LENGTH]); 3211 VNET_DEFINE_STATIC(int, isn_last); 3212 VNET_DEFINE_STATIC(int, isn_last_reseed); 3213 VNET_DEFINE_STATIC(u_int32_t, isn_offset); 3214 VNET_DEFINE_STATIC(u_int32_t, isn_offset_old); 3215 3216 #define V_isn_secret VNET(isn_secret) 3217 #define V_isn_last VNET(isn_last) 3218 #define V_isn_last_reseed VNET(isn_last_reseed) 3219 #define V_isn_offset VNET(isn_offset) 3220 #define V_isn_offset_old VNET(isn_offset_old) 3221 3222 tcp_seq 3223 tcp_new_isn(struct in_conninfo *inc) 3224 { 3225 tcp_seq new_isn; 3226 u_int32_t projected_offset; 3227 3228 ISN_LOCK(); 3229 /* Seed if this is the first use, reseed if requested. */ 3230 if ((V_isn_last_reseed == 0) || ((V_tcp_isn_reseed_interval > 0) && 3231 (((u_int)V_isn_last_reseed + (u_int)V_tcp_isn_reseed_interval*hz) 3232 < (u_int)ticks))) { 3233 arc4rand(&V_isn_secret, sizeof(V_isn_secret), 0); 3234 V_isn_last_reseed = ticks; 3235 } 3236 3237 /* Compute the hash and return the ISN. */ 3238 new_isn = (tcp_seq)tcp_keyed_hash(inc, V_isn_secret, 3239 sizeof(V_isn_secret)); 3240 V_isn_offset += ISN_STATIC_INCREMENT + 3241 (arc4random() & ISN_RANDOM_INCREMENT); 3242 if (ticks != V_isn_last) { 3243 projected_offset = V_isn_offset_old + 3244 ISN_BYTES_PER_SECOND / hz * (ticks - V_isn_last); 3245 if (SEQ_GT(projected_offset, V_isn_offset)) 3246 V_isn_offset = projected_offset; 3247 V_isn_offset_old = V_isn_offset; 3248 V_isn_last = ticks; 3249 } 3250 new_isn += V_isn_offset; 3251 ISN_UNLOCK(); 3252 return (new_isn); 3253 } 3254 3255 /* 3256 * When a specific ICMP unreachable message is received and the 3257 * connection state is SYN-SENT, drop the connection. This behavior 3258 * is controlled by the icmp_may_rst sysctl. 3259 */ 3260 static struct inpcb * 3261 tcp_drop_syn_sent(struct inpcb *inp, int errno) 3262 { 3263 struct tcpcb *tp; 3264 3265 NET_EPOCH_ASSERT(); 3266 INP_WLOCK_ASSERT(inp); 3267 3268 tp = intotcpcb(inp); 3269 if (tp->t_state != TCPS_SYN_SENT) 3270 return (inp); 3271 3272 if (IS_FASTOPEN(tp->t_flags)) 3273 tcp_fastopen_disable_path(tp); 3274 3275 tp = tcp_drop(tp, errno); 3276 if (tp != NULL) 3277 return (inp); 3278 else 3279 return (NULL); 3280 } 3281 3282 /* 3283 * When `need fragmentation' ICMP is received, update our idea of the MSS 3284 * based on the new value. Also nudge TCP to send something, since we 3285 * know the packet we just sent was dropped. 3286 * This duplicates some code in the tcp_mss() function in tcp_input.c. 3287 */ 3288 static struct inpcb * 3289 tcp_mtudisc_notify(struct inpcb *inp, int error) 3290 { 3291 3292 return (tcp_mtudisc(inp, -1)); 3293 } 3294 3295 static struct inpcb * 3296 tcp_mtudisc(struct inpcb *inp, int mtuoffer) 3297 { 3298 struct tcpcb *tp; 3299 struct socket *so; 3300 3301 INP_WLOCK_ASSERT(inp); 3302 3303 tp = intotcpcb(inp); 3304 KASSERT(tp != NULL, ("tcp_mtudisc: tp == NULL")); 3305 3306 tcp_mss_update(tp, -1, mtuoffer, NULL, NULL); 3307 3308 so = inp->inp_socket; 3309 SOCKBUF_LOCK(&so->so_snd); 3310 /* If the mss is larger than the socket buffer, decrease the mss. */ 3311 if (so->so_snd.sb_hiwat < tp->t_maxseg) 3312 tp->t_maxseg = so->so_snd.sb_hiwat; 3313 SOCKBUF_UNLOCK(&so->so_snd); 3314 3315 TCPSTAT_INC(tcps_mturesent); 3316 tp->t_rtttime = 0; 3317 tp->snd_nxt = tp->snd_una; 3318 tcp_free_sackholes(tp); 3319 tp->snd_recover = tp->snd_max; 3320 if (tp->t_flags & TF_SACK_PERMIT) 3321 EXIT_FASTRECOVERY(tp->t_flags); 3322 if (tp->t_fb->tfb_tcp_mtu_chg != NULL) { 3323 /* 3324 * Conceptually the snd_nxt setting 3325 * and freeing sack holes should 3326 * be done by the default stacks 3327 * own tfb_tcp_mtu_chg(). 3328 */ 3329 tp->t_fb->tfb_tcp_mtu_chg(tp); 3330 } 3331 if (tcp_output(tp) < 0) 3332 return (NULL); 3333 else 3334 return (inp); 3335 } 3336 3337 #ifdef INET 3338 /* 3339 * Look-up the routing entry to the peer of this inpcb. If no route 3340 * is found and it cannot be allocated, then return 0. This routine 3341 * is called by TCP routines that access the rmx structure and by 3342 * tcp_mss_update to get the peer/interface MTU. 3343 */ 3344 uint32_t 3345 tcp_maxmtu(struct in_conninfo *inc, struct tcp_ifcap *cap) 3346 { 3347 struct nhop_object *nh; 3348 struct ifnet *ifp; 3349 uint32_t maxmtu = 0; 3350 3351 KASSERT(inc != NULL, ("tcp_maxmtu with NULL in_conninfo pointer")); 3352 3353 if (inc->inc_faddr.s_addr != INADDR_ANY) { 3354 nh = fib4_lookup(inc->inc_fibnum, inc->inc_faddr, 0, NHR_NONE, 0); 3355 if (nh == NULL) 3356 return (0); 3357 3358 ifp = nh->nh_ifp; 3359 maxmtu = nh->nh_mtu; 3360 3361 /* Report additional interface capabilities. */ 3362 if (cap != NULL) { 3363 if (ifp->if_capenable & IFCAP_TSO4 && 3364 ifp->if_hwassist & CSUM_TSO) { 3365 cap->ifcap |= CSUM_TSO; 3366 cap->tsomax = ifp->if_hw_tsomax; 3367 cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount; 3368 cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize; 3369 } 3370 } 3371 } 3372 return (maxmtu); 3373 } 3374 #endif /* INET */ 3375 3376 #ifdef INET6 3377 uint32_t 3378 tcp_maxmtu6(struct in_conninfo *inc, struct tcp_ifcap *cap) 3379 { 3380 struct nhop_object *nh; 3381 struct in6_addr dst6; 3382 uint32_t scopeid; 3383 struct ifnet *ifp; 3384 uint32_t maxmtu = 0; 3385 3386 KASSERT(inc != NULL, ("tcp_maxmtu6 with NULL in_conninfo pointer")); 3387 3388 if (inc->inc_flags & INC_IPV6MINMTU) 3389 return (IPV6_MMTU); 3390 3391 if (!IN6_IS_ADDR_UNSPECIFIED(&inc->inc6_faddr)) { 3392 in6_splitscope(&inc->inc6_faddr, &dst6, &scopeid); 3393 nh = fib6_lookup(inc->inc_fibnum, &dst6, scopeid, NHR_NONE, 0); 3394 if (nh == NULL) 3395 return (0); 3396 3397 ifp = nh->nh_ifp; 3398 maxmtu = nh->nh_mtu; 3399 3400 /* Report additional interface capabilities. */ 3401 if (cap != NULL) { 3402 if (ifp->if_capenable & IFCAP_TSO6 && 3403 ifp->if_hwassist & CSUM_TSO) { 3404 cap->ifcap |= CSUM_TSO; 3405 cap->tsomax = ifp->if_hw_tsomax; 3406 cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount; 3407 cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize; 3408 } 3409 } 3410 } 3411 3412 return (maxmtu); 3413 } 3414 3415 /* 3416 * Handle setsockopt(IPV6_USE_MIN_MTU) by a TCP stack. 3417 * 3418 * XXXGL: we are updating inpcb here with INC_IPV6MINMTU flag. 3419 * The right place to do that is ip6_setpktopt() that has just been 3420 * executed. By the way it just filled ip6po_minmtu for us. 3421 */ 3422 void 3423 tcp6_use_min_mtu(struct tcpcb *tp) 3424 { 3425 struct inpcb *inp = tptoinpcb(tp); 3426 3427 INP_WLOCK_ASSERT(inp); 3428 /* 3429 * In case of the IPV6_USE_MIN_MTU socket 3430 * option, the INC_IPV6MINMTU flag to announce 3431 * a corresponding MSS during the initial 3432 * handshake. If the TCP connection is not in 3433 * the front states, just reduce the MSS being 3434 * used. This avoids the sending of TCP 3435 * segments which will be fragmented at the 3436 * IPv6 layer. 3437 */ 3438 inp->inp_inc.inc_flags |= INC_IPV6MINMTU; 3439 if ((tp->t_state >= TCPS_SYN_SENT) && 3440 (inp->inp_inc.inc_flags & INC_ISIPV6)) { 3441 struct ip6_pktopts *opt; 3442 3443 opt = inp->in6p_outputopts; 3444 if (opt != NULL && opt->ip6po_minmtu == IP6PO_MINMTU_ALL && 3445 tp->t_maxseg > TCP6_MSS) 3446 tp->t_maxseg = TCP6_MSS; 3447 } 3448 } 3449 #endif /* INET6 */ 3450 3451 /* 3452 * Calculate effective SMSS per RFC5681 definition for a given TCP 3453 * connection at its current state, taking into account SACK and etc. 3454 */ 3455 u_int 3456 tcp_maxseg(const struct tcpcb *tp) 3457 { 3458 u_int optlen; 3459 3460 if (tp->t_flags & TF_NOOPT) 3461 return (tp->t_maxseg); 3462 3463 /* 3464 * Here we have a simplified code from tcp_addoptions(), 3465 * without a proper loop, and having most of paddings hardcoded. 3466 * We might make mistakes with padding here in some edge cases, 3467 * but this is harmless, since result of tcp_maxseg() is used 3468 * only in cwnd and ssthresh estimations. 3469 */ 3470 if (TCPS_HAVEESTABLISHED(tp->t_state)) { 3471 if (tp->t_flags & TF_RCVD_TSTMP) 3472 optlen = TCPOLEN_TSTAMP_APPA; 3473 else 3474 optlen = 0; 3475 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3476 if (tp->t_flags & TF_SIGNATURE) 3477 optlen += PADTCPOLEN(TCPOLEN_SIGNATURE); 3478 #endif 3479 if ((tp->t_flags & TF_SACK_PERMIT) && tp->rcv_numsacks > 0) { 3480 optlen += TCPOLEN_SACKHDR; 3481 optlen += tp->rcv_numsacks * TCPOLEN_SACK; 3482 optlen = PADTCPOLEN(optlen); 3483 } 3484 } else { 3485 if (tp->t_flags & TF_REQ_TSTMP) 3486 optlen = TCPOLEN_TSTAMP_APPA; 3487 else 3488 optlen = PADTCPOLEN(TCPOLEN_MAXSEG); 3489 if (tp->t_flags & TF_REQ_SCALE) 3490 optlen += PADTCPOLEN(TCPOLEN_WINDOW); 3491 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3492 if (tp->t_flags & TF_SIGNATURE) 3493 optlen += PADTCPOLEN(TCPOLEN_SIGNATURE); 3494 #endif 3495 if (tp->t_flags & TF_SACK_PERMIT) 3496 optlen += PADTCPOLEN(TCPOLEN_SACK_PERMITTED); 3497 } 3498 #undef PAD 3499 optlen = min(optlen, TCP_MAXOLEN); 3500 return (tp->t_maxseg - optlen); 3501 } 3502 3503 3504 u_int 3505 tcp_fixed_maxseg(const struct tcpcb *tp) 3506 { 3507 int optlen; 3508 3509 if (tp->t_flags & TF_NOOPT) 3510 return (tp->t_maxseg); 3511 3512 /* 3513 * Here we have a simplified code from tcp_addoptions(), 3514 * without a proper loop, and having most of paddings hardcoded. 3515 * We only consider fixed options that we would send every 3516 * time I.e. SACK is not considered. This is important 3517 * for cc modules to figure out what the modulo of the 3518 * cwnd should be. 3519 */ 3520 #define PAD(len) ((((len) / 4) + !!((len) % 4)) * 4) 3521 if (TCPS_HAVEESTABLISHED(tp->t_state)) { 3522 if (tp->t_flags & TF_RCVD_TSTMP) 3523 optlen = TCPOLEN_TSTAMP_APPA; 3524 else 3525 optlen = 0; 3526 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3527 if (tp->t_flags & TF_SIGNATURE) 3528 optlen += PAD(TCPOLEN_SIGNATURE); 3529 #endif 3530 } else { 3531 if (tp->t_flags & TF_REQ_TSTMP) 3532 optlen = TCPOLEN_TSTAMP_APPA; 3533 else 3534 optlen = PAD(TCPOLEN_MAXSEG); 3535 if (tp->t_flags & TF_REQ_SCALE) 3536 optlen += PAD(TCPOLEN_WINDOW); 3537 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3538 if (tp->t_flags & TF_SIGNATURE) 3539 optlen += PAD(TCPOLEN_SIGNATURE); 3540 #endif 3541 if (tp->t_flags & TF_SACK_PERMIT) 3542 optlen += PAD(TCPOLEN_SACK_PERMITTED); 3543 } 3544 #undef PAD 3545 optlen = min(optlen, TCP_MAXOLEN); 3546 return (tp->t_maxseg - optlen); 3547 } 3548 3549 3550 3551 static int 3552 sysctl_drop(SYSCTL_HANDLER_ARGS) 3553 { 3554 /* addrs[0] is a foreign socket, addrs[1] is a local one. */ 3555 struct sockaddr_storage addrs[2]; 3556 struct inpcb *inp; 3557 struct tcpcb *tp; 3558 #ifdef INET 3559 struct sockaddr_in *fin = NULL, *lin = NULL; 3560 #endif 3561 struct epoch_tracker et; 3562 #ifdef INET6 3563 struct sockaddr_in6 *fin6, *lin6; 3564 #endif 3565 int error; 3566 3567 inp = NULL; 3568 #ifdef INET6 3569 fin6 = lin6 = NULL; 3570 #endif 3571 error = 0; 3572 3573 if (req->oldptr != NULL || req->oldlen != 0) 3574 return (EINVAL); 3575 if (req->newptr == NULL) 3576 return (EPERM); 3577 if (req->newlen < sizeof(addrs)) 3578 return (ENOMEM); 3579 error = SYSCTL_IN(req, &addrs, sizeof(addrs)); 3580 if (error) 3581 return (error); 3582 3583 switch (addrs[0].ss_family) { 3584 #ifdef INET6 3585 case AF_INET6: 3586 fin6 = (struct sockaddr_in6 *)&addrs[0]; 3587 lin6 = (struct sockaddr_in6 *)&addrs[1]; 3588 if (fin6->sin6_len != sizeof(struct sockaddr_in6) || 3589 lin6->sin6_len != sizeof(struct sockaddr_in6)) 3590 return (EINVAL); 3591 if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr)) { 3592 if (!IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr)) 3593 return (EINVAL); 3594 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[0]); 3595 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[1]); 3596 #ifdef INET 3597 fin = (struct sockaddr_in *)&addrs[0]; 3598 lin = (struct sockaddr_in *)&addrs[1]; 3599 #endif 3600 break; 3601 } 3602 error = sa6_embedscope(fin6, V_ip6_use_defzone); 3603 if (error) 3604 return (error); 3605 error = sa6_embedscope(lin6, V_ip6_use_defzone); 3606 if (error) 3607 return (error); 3608 break; 3609 #endif 3610 #ifdef INET 3611 case AF_INET: 3612 fin = (struct sockaddr_in *)&addrs[0]; 3613 lin = (struct sockaddr_in *)&addrs[1]; 3614 if (fin->sin_len != sizeof(struct sockaddr_in) || 3615 lin->sin_len != sizeof(struct sockaddr_in)) 3616 return (EINVAL); 3617 break; 3618 #endif 3619 default: 3620 return (EINVAL); 3621 } 3622 NET_EPOCH_ENTER(et); 3623 switch (addrs[0].ss_family) { 3624 #ifdef INET6 3625 case AF_INET6: 3626 inp = in6_pcblookup(&V_tcbinfo, &fin6->sin6_addr, 3627 fin6->sin6_port, &lin6->sin6_addr, lin6->sin6_port, 3628 INPLOOKUP_WLOCKPCB, NULL); 3629 break; 3630 #endif 3631 #ifdef INET 3632 case AF_INET: 3633 inp = in_pcblookup(&V_tcbinfo, fin->sin_addr, fin->sin_port, 3634 lin->sin_addr, lin->sin_port, INPLOOKUP_WLOCKPCB, NULL); 3635 break; 3636 #endif 3637 } 3638 if (inp != NULL) { 3639 if (!SOLISTENING(inp->inp_socket)) { 3640 tp = intotcpcb(inp); 3641 tp = tcp_drop(tp, ECONNABORTED); 3642 if (tp != NULL) 3643 INP_WUNLOCK(inp); 3644 } else 3645 INP_WUNLOCK(inp); 3646 } else 3647 error = ESRCH; 3648 NET_EPOCH_EXIT(et); 3649 return (error); 3650 } 3651 3652 SYSCTL_PROC(_net_inet_tcp, TCPCTL_DROP, drop, 3653 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | 3654 CTLFLAG_NEEDGIANT, NULL, 0, sysctl_drop, "", 3655 "Drop TCP connection"); 3656 3657 static int 3658 tcp_sysctl_setsockopt(SYSCTL_HANDLER_ARGS) 3659 { 3660 return (sysctl_setsockopt(oidp, arg1, arg2, req, &V_tcbinfo, 3661 &tcp_ctloutput_set)); 3662 } 3663 3664 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, setsockopt, 3665 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | 3666 CTLFLAG_MPSAFE, NULL, 0, tcp_sysctl_setsockopt, "", 3667 "Set socket option for TCP endpoint"); 3668 3669 #ifdef KERN_TLS 3670 static int 3671 sysctl_switch_tls(SYSCTL_HANDLER_ARGS) 3672 { 3673 /* addrs[0] is a foreign socket, addrs[1] is a local one. */ 3674 struct sockaddr_storage addrs[2]; 3675 struct inpcb *inp; 3676 #ifdef INET 3677 struct sockaddr_in *fin = NULL, *lin = NULL; 3678 #endif 3679 struct epoch_tracker et; 3680 #ifdef INET6 3681 struct sockaddr_in6 *fin6, *lin6; 3682 #endif 3683 int error; 3684 3685 inp = NULL; 3686 #ifdef INET6 3687 fin6 = lin6 = NULL; 3688 #endif 3689 error = 0; 3690 3691 if (req->oldptr != NULL || req->oldlen != 0) 3692 return (EINVAL); 3693 if (req->newptr == NULL) 3694 return (EPERM); 3695 if (req->newlen < sizeof(addrs)) 3696 return (ENOMEM); 3697 error = SYSCTL_IN(req, &addrs, sizeof(addrs)); 3698 if (error) 3699 return (error); 3700 3701 switch (addrs[0].ss_family) { 3702 #ifdef INET6 3703 case AF_INET6: 3704 fin6 = (struct sockaddr_in6 *)&addrs[0]; 3705 lin6 = (struct sockaddr_in6 *)&addrs[1]; 3706 if (fin6->sin6_len != sizeof(struct sockaddr_in6) || 3707 lin6->sin6_len != sizeof(struct sockaddr_in6)) 3708 return (EINVAL); 3709 if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr)) { 3710 if (!IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr)) 3711 return (EINVAL); 3712 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[0]); 3713 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[1]); 3714 #ifdef INET 3715 fin = (struct sockaddr_in *)&addrs[0]; 3716 lin = (struct sockaddr_in *)&addrs[1]; 3717 #endif 3718 break; 3719 } 3720 error = sa6_embedscope(fin6, V_ip6_use_defzone); 3721 if (error) 3722 return (error); 3723 error = sa6_embedscope(lin6, V_ip6_use_defzone); 3724 if (error) 3725 return (error); 3726 break; 3727 #endif 3728 #ifdef INET 3729 case AF_INET: 3730 fin = (struct sockaddr_in *)&addrs[0]; 3731 lin = (struct sockaddr_in *)&addrs[1]; 3732 if (fin->sin_len != sizeof(struct sockaddr_in) || 3733 lin->sin_len != sizeof(struct sockaddr_in)) 3734 return (EINVAL); 3735 break; 3736 #endif 3737 default: 3738 return (EINVAL); 3739 } 3740 NET_EPOCH_ENTER(et); 3741 switch (addrs[0].ss_family) { 3742 #ifdef INET6 3743 case AF_INET6: 3744 inp = in6_pcblookup(&V_tcbinfo, &fin6->sin6_addr, 3745 fin6->sin6_port, &lin6->sin6_addr, lin6->sin6_port, 3746 INPLOOKUP_WLOCKPCB, NULL); 3747 break; 3748 #endif 3749 #ifdef INET 3750 case AF_INET: 3751 inp = in_pcblookup(&V_tcbinfo, fin->sin_addr, fin->sin_port, 3752 lin->sin_addr, lin->sin_port, INPLOOKUP_WLOCKPCB, NULL); 3753 break; 3754 #endif 3755 } 3756 NET_EPOCH_EXIT(et); 3757 if (inp != NULL) { 3758 struct socket *so; 3759 3760 so = inp->inp_socket; 3761 soref(so); 3762 error = ktls_set_tx_mode(so, 3763 arg2 == 0 ? TCP_TLS_MODE_SW : TCP_TLS_MODE_IFNET); 3764 INP_WUNLOCK(inp); 3765 sorele(so); 3766 } else 3767 error = ESRCH; 3768 return (error); 3769 } 3770 3771 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, switch_to_sw_tls, 3772 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | 3773 CTLFLAG_NEEDGIANT, NULL, 0, sysctl_switch_tls, "", 3774 "Switch TCP connection to SW TLS"); 3775 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, switch_to_ifnet_tls, 3776 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | 3777 CTLFLAG_NEEDGIANT, NULL, 1, sysctl_switch_tls, "", 3778 "Switch TCP connection to ifnet TLS"); 3779 #endif 3780 3781 /* 3782 * Generate a standardized TCP log line for use throughout the 3783 * tcp subsystem. Memory allocation is done with M_NOWAIT to 3784 * allow use in the interrupt context. 3785 * 3786 * NB: The caller MUST free(s, M_TCPLOG) the returned string. 3787 * NB: The function may return NULL if memory allocation failed. 3788 * 3789 * Due to header inclusion and ordering limitations the struct ip 3790 * and ip6_hdr pointers have to be passed as void pointers. 3791 */ 3792 char * 3793 tcp_log_vain(struct in_conninfo *inc, struct tcphdr *th, const void *ip4hdr, 3794 const void *ip6hdr) 3795 { 3796 3797 /* Is logging enabled? */ 3798 if (V_tcp_log_in_vain == 0) 3799 return (NULL); 3800 3801 return (tcp_log_addr(inc, th, ip4hdr, ip6hdr)); 3802 } 3803 3804 char * 3805 tcp_log_addrs(struct in_conninfo *inc, struct tcphdr *th, const void *ip4hdr, 3806 const void *ip6hdr) 3807 { 3808 3809 /* Is logging enabled? */ 3810 if (tcp_log_debug == 0) 3811 return (NULL); 3812 3813 return (tcp_log_addr(inc, th, ip4hdr, ip6hdr)); 3814 } 3815 3816 static char * 3817 tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th, const void *ip4hdr, 3818 const void *ip6hdr) 3819 { 3820 char *s, *sp; 3821 size_t size; 3822 #ifdef INET 3823 const struct ip *ip = (const struct ip *)ip4hdr; 3824 #endif 3825 #ifdef INET6 3826 const struct ip6_hdr *ip6 = (const struct ip6_hdr *)ip6hdr; 3827 #endif /* INET6 */ 3828 3829 /* 3830 * The log line looks like this: 3831 * "TCP: [1.2.3.4]:50332 to [1.2.3.4]:80 tcpflags 0x2<SYN>" 3832 */ 3833 size = sizeof("TCP: []:12345 to []:12345 tcpflags 0x2<>") + 3834 sizeof(PRINT_TH_FLAGS) + 1 + 3835 #ifdef INET6 3836 2 * INET6_ADDRSTRLEN; 3837 #else 3838 2 * INET_ADDRSTRLEN; 3839 #endif /* INET6 */ 3840 3841 s = malloc(size, M_TCPLOG, M_ZERO|M_NOWAIT); 3842 if (s == NULL) 3843 return (NULL); 3844 3845 strcat(s, "TCP: ["); 3846 sp = s + strlen(s); 3847 3848 if (inc && ((inc->inc_flags & INC_ISIPV6) == 0)) { 3849 inet_ntoa_r(inc->inc_faddr, sp); 3850 sp = s + strlen(s); 3851 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport)); 3852 sp = s + strlen(s); 3853 inet_ntoa_r(inc->inc_laddr, sp); 3854 sp = s + strlen(s); 3855 sprintf(sp, "]:%i", ntohs(inc->inc_lport)); 3856 #ifdef INET6 3857 } else if (inc) { 3858 ip6_sprintf(sp, &inc->inc6_faddr); 3859 sp = s + strlen(s); 3860 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport)); 3861 sp = s + strlen(s); 3862 ip6_sprintf(sp, &inc->inc6_laddr); 3863 sp = s + strlen(s); 3864 sprintf(sp, "]:%i", ntohs(inc->inc_lport)); 3865 } else if (ip6 && th) { 3866 ip6_sprintf(sp, &ip6->ip6_src); 3867 sp = s + strlen(s); 3868 sprintf(sp, "]:%i to [", ntohs(th->th_sport)); 3869 sp = s + strlen(s); 3870 ip6_sprintf(sp, &ip6->ip6_dst); 3871 sp = s + strlen(s); 3872 sprintf(sp, "]:%i", ntohs(th->th_dport)); 3873 #endif /* INET6 */ 3874 #ifdef INET 3875 } else if (ip && th) { 3876 inet_ntoa_r(ip->ip_src, sp); 3877 sp = s + strlen(s); 3878 sprintf(sp, "]:%i to [", ntohs(th->th_sport)); 3879 sp = s + strlen(s); 3880 inet_ntoa_r(ip->ip_dst, sp); 3881 sp = s + strlen(s); 3882 sprintf(sp, "]:%i", ntohs(th->th_dport)); 3883 #endif /* INET */ 3884 } else { 3885 free(s, M_TCPLOG); 3886 return (NULL); 3887 } 3888 sp = s + strlen(s); 3889 if (th) 3890 sprintf(sp, " tcpflags 0x%b", tcp_get_flags(th), PRINT_TH_FLAGS); 3891 if (*(s + size - 1) != '\0') 3892 panic("%s: string too long", __func__); 3893 return (s); 3894 } 3895 3896 /* 3897 * A subroutine which makes it easy to track TCP state changes with DTrace. 3898 * This function shouldn't be called for t_state initializations that don't 3899 * correspond to actual TCP state transitions. 3900 */ 3901 void 3902 tcp_state_change(struct tcpcb *tp, int newstate) 3903 { 3904 #if defined(KDTRACE_HOOKS) 3905 int pstate = tp->t_state; 3906 #endif 3907 3908 TCPSTATES_DEC(tp->t_state); 3909 TCPSTATES_INC(newstate); 3910 tp->t_state = newstate; 3911 TCP_PROBE6(state__change, NULL, tp, NULL, tp, NULL, pstate); 3912 } 3913 3914 /* 3915 * Create an external-format (``xtcpcb'') structure using the information in 3916 * the kernel-format tcpcb structure pointed to by tp. This is done to 3917 * reduce the spew of irrelevant information over this interface, to isolate 3918 * user code from changes in the kernel structure, and potentially to provide 3919 * information-hiding if we decide that some of this information should be 3920 * hidden from users. 3921 */ 3922 void 3923 tcp_inptoxtp(const struct inpcb *inp, struct xtcpcb *xt) 3924 { 3925 struct tcpcb *tp = intotcpcb(inp); 3926 sbintime_t now; 3927 3928 bzero(xt, sizeof(*xt)); 3929 xt->t_state = tp->t_state; 3930 xt->t_logstate = tcp_get_bblog_state(tp); 3931 xt->t_flags = tp->t_flags; 3932 xt->t_sndzerowin = tp->t_sndzerowin; 3933 xt->t_sndrexmitpack = tp->t_sndrexmitpack; 3934 xt->t_rcvoopack = tp->t_rcvoopack; 3935 xt->t_rcv_wnd = tp->rcv_wnd; 3936 xt->t_snd_wnd = tp->snd_wnd; 3937 xt->t_snd_cwnd = tp->snd_cwnd; 3938 xt->t_snd_ssthresh = tp->snd_ssthresh; 3939 xt->t_dsack_bytes = tp->t_dsack_bytes; 3940 xt->t_dsack_tlp_bytes = tp->t_dsack_tlp_bytes; 3941 xt->t_dsack_pack = tp->t_dsack_pack; 3942 xt->t_maxseg = tp->t_maxseg; 3943 xt->xt_ecn = (tp->t_flags2 & TF2_ECN_PERMIT) ? 1 : 0 + 3944 (tp->t_flags2 & TF2_ACE_PERMIT) ? 2 : 0; 3945 3946 now = getsbinuptime(); 3947 #define COPYTIMER(which,where) do { \ 3948 if (tp->t_timers[which] != SBT_MAX) \ 3949 xt->where = (tp->t_timers[which] - now) / SBT_1MS; \ 3950 else \ 3951 xt->where = 0; \ 3952 } while (0) 3953 COPYTIMER(TT_DELACK, tt_delack); 3954 COPYTIMER(TT_REXMT, tt_rexmt); 3955 COPYTIMER(TT_PERSIST, tt_persist); 3956 COPYTIMER(TT_KEEP, tt_keep); 3957 COPYTIMER(TT_2MSL, tt_2msl); 3958 #undef COPYTIMER 3959 xt->t_rcvtime = 1000 * (ticks - tp->t_rcvtime) / hz; 3960 3961 xt->xt_encaps_port = tp->t_port; 3962 bcopy(tp->t_fb->tfb_tcp_block_name, xt->xt_stack, 3963 TCP_FUNCTION_NAME_LEN_MAX); 3964 bcopy(CC_ALGO(tp)->name, xt->xt_cc, TCP_CA_NAME_MAX); 3965 #ifdef TCP_BLACKBOX 3966 (void)tcp_log_get_id(tp, xt->xt_logid); 3967 #endif 3968 3969 xt->xt_len = sizeof(struct xtcpcb); 3970 in_pcbtoxinpcb(inp, &xt->xt_inp); 3971 /* 3972 * TCP doesn't use inp_ppcb pointer, we embed inpcb into tcpcb. 3973 * Fixup the pointer that in_pcbtoxinpcb() has set. When printing 3974 * TCP netstat(1) used to use this pointer, so this fixup needs to 3975 * stay for stable/14. 3976 */ 3977 xt->xt_inp.inp_ppcb = (uintptr_t)tp; 3978 } 3979 3980 void 3981 tcp_log_end_status(struct tcpcb *tp, uint8_t status) 3982 { 3983 uint32_t bit, i; 3984 3985 if ((tp == NULL) || 3986 (status > TCP_EI_STATUS_MAX_VALUE) || 3987 (status == 0)) { 3988 /* Invalid */ 3989 return; 3990 } 3991 if (status > (sizeof(uint32_t) * 8)) { 3992 /* Should this be a KASSERT? */ 3993 return; 3994 } 3995 bit = 1U << (status - 1); 3996 if (bit & tp->t_end_info_status) { 3997 /* already logged */ 3998 return; 3999 } 4000 for (i = 0; i < TCP_END_BYTE_INFO; i++) { 4001 if (tp->t_end_info_bytes[i] == TCP_EI_EMPTY_SLOT) { 4002 tp->t_end_info_bytes[i] = status; 4003 tp->t_end_info_status |= bit; 4004 break; 4005 } 4006 } 4007 } 4008 4009 int 4010 tcp_can_enable_pacing(void) 4011 { 4012 4013 if ((tcp_pacing_limit == -1) || 4014 (tcp_pacing_limit > number_of_tcp_connections_pacing)) { 4015 atomic_fetchadd_int(&number_of_tcp_connections_pacing, 1); 4016 shadow_num_connections = number_of_tcp_connections_pacing; 4017 return (1); 4018 } else { 4019 counter_u64_add(tcp_pacing_failures, 1); 4020 return (0); 4021 } 4022 } 4023 4024 static uint8_t tcp_pacing_warning = 0; 4025 4026 void 4027 tcp_decrement_paced_conn(void) 4028 { 4029 uint32_t ret; 4030 4031 ret = atomic_fetchadd_int(&number_of_tcp_connections_pacing, -1); 4032 shadow_num_connections = number_of_tcp_connections_pacing; 4033 KASSERT(ret != 0, ("tcp_paced_connection_exits -1 would cause wrap?")); 4034 if (ret == 0) { 4035 if (tcp_pacing_limit != -1) { 4036 printf("Warning all pacing is now disabled, count decrements invalidly!\n"); 4037 tcp_pacing_limit = 0; 4038 } else if (tcp_pacing_warning == 0) { 4039 printf("Warning pacing count is invalid, invalid decrement\n"); 4040 tcp_pacing_warning = 1; 4041 } 4042 } 4043 } 4044 4045 static void 4046 tcp_default_switch_failed(struct tcpcb *tp) 4047 { 4048 /* 4049 * If a switch fails we only need to 4050 * care about two things: 4051 * a) The inp_flags2 4052 * and 4053 * b) The timer granularity. 4054 * Timeouts, at least for now, don't use the 4055 * old callout system in the other stacks so 4056 * those are hopefully safe. 4057 */ 4058 tcp_lro_features_off(tptoinpcb(tp)); 4059 tcp_change_time_units(tp, TCP_TMR_GRANULARITY_TICKS); 4060 } 4061 4062 #ifdef TCP_ACCOUNTING 4063 int 4064 tcp_do_ack_accounting(struct tcpcb *tp, struct tcphdr *th, struct tcpopt *to, uint32_t tiwin, int mss) 4065 { 4066 if (SEQ_LT(th->th_ack, tp->snd_una)) { 4067 /* Do we have a SACK? */ 4068 if (to->to_flags & TOF_SACK) { 4069 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4070 tp->tcp_cnt_counters[ACK_SACK]++; 4071 } 4072 return (ACK_SACK); 4073 } else { 4074 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4075 tp->tcp_cnt_counters[ACK_BEHIND]++; 4076 } 4077 return (ACK_BEHIND); 4078 } 4079 } else if (th->th_ack == tp->snd_una) { 4080 /* Do we have a SACK? */ 4081 if (to->to_flags & TOF_SACK) { 4082 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4083 tp->tcp_cnt_counters[ACK_SACK]++; 4084 } 4085 return (ACK_SACK); 4086 } else if (tiwin != tp->snd_wnd) { 4087 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4088 tp->tcp_cnt_counters[ACK_RWND]++; 4089 } 4090 return (ACK_RWND); 4091 } else { 4092 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4093 tp->tcp_cnt_counters[ACK_DUPACK]++; 4094 } 4095 return (ACK_DUPACK); 4096 } 4097 } else { 4098 if (!SEQ_GT(th->th_ack, tp->snd_max)) { 4099 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4100 tp->tcp_cnt_counters[CNT_OF_ACKS_IN] += (((th->th_ack - tp->snd_una) + mss - 1)/mss); 4101 } 4102 } 4103 if (to->to_flags & TOF_SACK) { 4104 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4105 tp->tcp_cnt_counters[ACK_CUMACK_SACK]++; 4106 } 4107 return (ACK_CUMACK_SACK); 4108 } else { 4109 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4110 tp->tcp_cnt_counters[ACK_CUMACK]++; 4111 } 4112 return (ACK_CUMACK); 4113 } 4114 } 4115 } 4116 #endif 4117 4118 void 4119 tcp_change_time_units(struct tcpcb *tp, int granularity) 4120 { 4121 if (tp->t_tmr_granularity == granularity) { 4122 /* We are there */ 4123 return; 4124 } 4125 if (granularity == TCP_TMR_GRANULARITY_USEC) { 4126 KASSERT((tp->t_tmr_granularity == TCP_TMR_GRANULARITY_TICKS), 4127 ("Granularity is not TICKS its %u in tp:%p", 4128 tp->t_tmr_granularity, tp)); 4129 tp->t_rttlow = TICKS_2_USEC(tp->t_rttlow); 4130 if (tp->t_srtt > 1) { 4131 uint32_t val, frac; 4132 4133 val = tp->t_srtt >> TCP_RTT_SHIFT; 4134 frac = tp->t_srtt & 0x1f; 4135 tp->t_srtt = TICKS_2_USEC(val); 4136 /* 4137 * frac is the fractional part of the srtt (if any) 4138 * but its in ticks and every bit represents 4139 * 1/32nd of a hz. 4140 */ 4141 if (frac) { 4142 if (hz == 1000) { 4143 frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_MSEC) / (uint64_t)TCP_RTT_SCALE); 4144 } else { 4145 frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_SEC) / ((uint64_t)(hz) * (uint64_t)TCP_RTT_SCALE)); 4146 } 4147 tp->t_srtt += frac; 4148 } 4149 } 4150 if (tp->t_rttvar) { 4151 uint32_t val, frac; 4152 4153 val = tp->t_rttvar >> TCP_RTTVAR_SHIFT; 4154 frac = tp->t_rttvar & 0x1f; 4155 tp->t_rttvar = TICKS_2_USEC(val); 4156 /* 4157 * frac is the fractional part of the srtt (if any) 4158 * but its in ticks and every bit represents 4159 * 1/32nd of a hz. 4160 */ 4161 if (frac) { 4162 if (hz == 1000) { 4163 frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_MSEC) / (uint64_t)TCP_RTT_SCALE); 4164 } else { 4165 frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_SEC) / ((uint64_t)(hz) * (uint64_t)TCP_RTT_SCALE)); 4166 } 4167 tp->t_rttvar += frac; 4168 } 4169 } 4170 tp->t_tmr_granularity = TCP_TMR_GRANULARITY_USEC; 4171 } else if (granularity == TCP_TMR_GRANULARITY_TICKS) { 4172 /* Convert back to ticks, with */ 4173 KASSERT((tp->t_tmr_granularity == TCP_TMR_GRANULARITY_USEC), 4174 ("Granularity is not USEC its %u in tp:%p", 4175 tp->t_tmr_granularity, tp)); 4176 if (tp->t_srtt > 1) { 4177 uint32_t val, frac; 4178 4179 val = USEC_2_TICKS(tp->t_srtt); 4180 frac = tp->t_srtt % (HPTS_USEC_IN_SEC / hz); 4181 tp->t_srtt = val << TCP_RTT_SHIFT; 4182 /* 4183 * frac is the fractional part here is left 4184 * over from converting to hz and shifting. 4185 * We need to convert this to the 5 bit 4186 * remainder. 4187 */ 4188 if (frac) { 4189 if (hz == 1000) { 4190 frac = (((uint64_t)frac * (uint64_t)TCP_RTT_SCALE) / (uint64_t)HPTS_USEC_IN_MSEC); 4191 } else { 4192 frac = (((uint64_t)frac * (uint64_t)(hz) * (uint64_t)TCP_RTT_SCALE) /(uint64_t)HPTS_USEC_IN_SEC); 4193 } 4194 tp->t_srtt += frac; 4195 } 4196 } 4197 if (tp->t_rttvar) { 4198 uint32_t val, frac; 4199 4200 val = USEC_2_TICKS(tp->t_rttvar); 4201 frac = tp->t_srtt % (HPTS_USEC_IN_SEC / hz); 4202 tp->t_rttvar = val << TCP_RTTVAR_SHIFT; 4203 /* 4204 * frac is the fractional part here is left 4205 * over from converting to hz and shifting. 4206 * We need to convert this to the 5 bit 4207 * remainder. 4208 */ 4209 if (frac) { 4210 if (hz == 1000) { 4211 frac = (((uint64_t)frac * (uint64_t)TCP_RTT_SCALE) / (uint64_t)HPTS_USEC_IN_MSEC); 4212 } else { 4213 frac = (((uint64_t)frac * (uint64_t)(hz) * (uint64_t)TCP_RTT_SCALE) /(uint64_t)HPTS_USEC_IN_SEC); 4214 } 4215 tp->t_rttvar += frac; 4216 } 4217 } 4218 tp->t_rttlow = USEC_2_TICKS(tp->t_rttlow); 4219 tp->t_tmr_granularity = TCP_TMR_GRANULARITY_TICKS; 4220 } 4221 #ifdef INVARIANTS 4222 else { 4223 panic("Unknown granularity:%d tp:%p", 4224 granularity, tp); 4225 } 4226 #endif 4227 } 4228 4229 void 4230 tcp_handle_orphaned_packets(struct tcpcb *tp) 4231 { 4232 struct mbuf *save, *m, *prev; 4233 /* 4234 * Called when a stack switch is occuring from the fini() 4235 * of the old stack. We assue the init() as already been 4236 * run of the new stack and it has set the inp_flags2 to 4237 * what it supports. This function will then deal with any 4238 * differences i.e. cleanup packets that maybe queued that 4239 * the newstack does not support. 4240 */ 4241 4242 if (tptoinpcb(tp)->inp_flags2 & INP_MBUF_L_ACKS) 4243 return; 4244 if ((tptoinpcb(tp)->inp_flags2 & INP_SUPPORTS_MBUFQ) == 0 && 4245 !STAILQ_EMPTY(&tp->t_inqueue)) { 4246 /* 4247 * It is unsafe to process the packets since a 4248 * reset may be lurking in them (its rare but it 4249 * can occur). If we were to find a RST, then we 4250 * would end up dropping the connection and the 4251 * INP lock, so when we return the caller (tcp_usrreq) 4252 * will blow up when it trys to unlock the inp. 4253 * This new stack does not do any fancy LRO features 4254 * so all we can do is toss the packets. 4255 */ 4256 m = STAILQ_FIRST(&tp->t_inqueue); 4257 STAILQ_INIT(&tp->t_inqueue); 4258 STAILQ_FOREACH_FROM_SAFE(m, &tp->t_inqueue, m_stailqpkt, save) 4259 m_freem(m); 4260 } else { 4261 /* 4262 * Here we have a stack that does mbuf queuing but 4263 * does not support compressed ack's. We must 4264 * walk all the mbufs and discard any compressed acks. 4265 */ 4266 STAILQ_FOREACH_SAFE(m, &tp->t_inqueue, m_stailqpkt, save) { 4267 if (m->m_flags & M_ACKCMP) { 4268 if (m == STAILQ_FIRST(&tp->t_inqueue)) 4269 STAILQ_REMOVE_HEAD(&tp->t_inqueue, 4270 m_stailqpkt); 4271 else 4272 STAILQ_REMOVE_AFTER(&tp->t_inqueue, 4273 prev, m_stailqpkt); 4274 m_freem(m); 4275 } else 4276 prev = m; 4277 } 4278 } 4279 } 4280 4281 #ifdef TCP_REQUEST_TRK 4282 uint32_t 4283 tcp_estimate_tls_overhead(struct socket *so, uint64_t tls_usr_bytes) 4284 { 4285 #ifdef KERN_TLS 4286 struct ktls_session *tls; 4287 uint32_t rec_oh, records; 4288 4289 tls = so->so_snd.sb_tls_info; 4290 if (tls == NULL) 4291 return (0); 4292 4293 rec_oh = tls->params.tls_hlen + tls->params.tls_tlen; 4294 records = ((tls_usr_bytes + tls->params.max_frame_len - 1)/tls->params.max_frame_len); 4295 return (records * rec_oh); 4296 #else 4297 return (0); 4298 #endif 4299 } 4300 4301 extern uint32_t tcp_stale_entry_time; 4302 uint32_t tcp_stale_entry_time = 250000; 4303 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, usrlog_stale, CTLFLAG_RW, 4304 &tcp_stale_entry_time, 250000, "Time that a http entry without a sendfile ages out"); 4305 4306 void 4307 tcp_http_log_req_info(struct tcpcb *tp, struct http_sendfile_track *http, 4308 uint16_t slot, uint8_t val, uint64_t offset, uint64_t nbytes) 4309 { 4310 if (tcp_bblogging_on(tp)) { 4311 union tcp_log_stackspecific log; 4312 struct timeval tv; 4313 4314 memset(&log.u_bbr, 0, sizeof(log.u_bbr)); 4315 #ifdef TCPHPTS 4316 log.u_bbr.inhpts = tcp_in_hpts(tptoinpcb(tp)); 4317 #endif 4318 log.u_bbr.flex8 = val; 4319 log.u_bbr.rttProp = http->timestamp; 4320 log.u_bbr.delRate = http->start; 4321 log.u_bbr.cur_del_rate = http->end; 4322 log.u_bbr.flex1 = http->start_seq; 4323 log.u_bbr.flex2 = http->end_seq; 4324 log.u_bbr.flex3 = http->flags; 4325 log.u_bbr.flex4 = ((http->localtime >> 32) & 0x00000000ffffffff); 4326 log.u_bbr.flex5 = (http->localtime & 0x00000000ffffffff); 4327 log.u_bbr.flex7 = slot; 4328 log.u_bbr.bw_inuse = offset; 4329 /* nbytes = flex6 | epoch */ 4330 log.u_bbr.flex6 = ((nbytes >> 32) & 0x00000000ffffffff); 4331 log.u_bbr.epoch = (nbytes & 0x00000000ffffffff); 4332 /* cspr = lt_epoch | pkts_out */ 4333 log.u_bbr.lt_epoch = ((http->cspr >> 32) & 0x00000000ffffffff); 4334 log.u_bbr.pkts_out |= (http->cspr & 0x00000000ffffffff); 4335 log.u_bbr.applimited = tp->t_http_closed; 4336 log.u_bbr.applimited <<= 8; 4337 log.u_bbr.applimited |= tp->t_http_open; 4338 log.u_bbr.applimited <<= 8; 4339 log.u_bbr.applimited |= tp->t_http_req; 4340 log.u_bbr.timeStamp = tcp_get_usecs(&tv); 4341 TCP_LOG_EVENTP(tp, NULL, 4342 &tptosocket(tp)->so_rcv, 4343 &tptosocket(tp)->so_snd, 4344 TCP_LOG_HTTP_T, 0, 4345 0, &log, false, &tv); 4346 } 4347 } 4348 4349 void 4350 tcp_http_free_a_slot(struct tcpcb *tp, struct http_sendfile_track *ent) 4351 { 4352 if (tp->t_http_req > 0) 4353 tp->t_http_req--; 4354 if (ent->flags & TCP_HTTP_TRACK_FLG_OPEN) { 4355 if (tp->t_http_open > 0) 4356 tp->t_http_open--; 4357 } else { 4358 if (tp->t_http_closed > 0) 4359 tp->t_http_closed--; 4360 } 4361 ent->flags = TCP_HTTP_TRACK_FLG_EMPTY; 4362 } 4363 4364 static void 4365 tcp_http_check_for_stale_entries(struct tcpcb *tp, uint64_t ts, int rm_oldest) 4366 { 4367 struct http_sendfile_track *ent; 4368 uint64_t time_delta, oldest_delta; 4369 int i, oldest, oldest_set = 0, cnt_rm = 0; 4370 4371 for(i = 0; i < MAX_TCP_HTTP_REQ; i++) { 4372 ent = &tp->t_http_info[i]; 4373 if (ent->flags != TCP_HTTP_TRACK_FLG_USED) { 4374 /* 4375 * We only care about closed end ranges 4376 * that are allocated and have no sendfile 4377 * ever touching them. They would be in 4378 * state USED. 4379 */ 4380 continue; 4381 } 4382 if (ts >= ent->localtime) 4383 time_delta = ts - ent->localtime; 4384 else 4385 time_delta = 0; 4386 if (time_delta && 4387 ((oldest_delta < time_delta) || (oldest_set == 0))) { 4388 oldest_set = 1; 4389 oldest = i; 4390 oldest_delta = time_delta; 4391 } 4392 if (tcp_stale_entry_time && (time_delta >= tcp_stale_entry_time)) { 4393 /* 4394 * No sendfile in a our time-limit 4395 * time to purge it. 4396 */ 4397 cnt_rm++; 4398 tcp_http_log_req_info(tp, &tp->t_http_info[i], i, TCP_HTTP_REQ_LOG_STALE, 4399 time_delta, 0); 4400 tcp_http_free_a_slot(tp, ent); 4401 } 4402 } 4403 if ((cnt_rm == 0) && rm_oldest && oldest_set) { 4404 ent = &tp->t_http_info[oldest]; 4405 tcp_http_log_req_info(tp, &tp->t_http_info[i], i, TCP_HTTP_REQ_LOG_STALE, 4406 oldest_delta, 1); 4407 tcp_http_free_a_slot(tp, ent); 4408 } 4409 } 4410 4411 int 4412 tcp_http_check_for_comp(struct tcpcb *tp, tcp_seq ack_point) 4413 { 4414 int i, ret=0; 4415 struct http_sendfile_track *ent; 4416 4417 /* Clean up any old closed end requests that are now completed */ 4418 if (tp->t_http_req == 0) 4419 return(0); 4420 if (tp->t_http_closed == 0) 4421 return(0); 4422 for(i = 0; i < MAX_TCP_HTTP_REQ; i++) { 4423 ent = &tp->t_http_info[i]; 4424 /* Skip empty ones */ 4425 if (ent->flags == TCP_HTTP_TRACK_FLG_EMPTY) 4426 continue; 4427 /* Skip open ones */ 4428 if (ent->flags & TCP_HTTP_TRACK_FLG_OPEN) 4429 continue; 4430 if (SEQ_GEQ(ack_point, ent->end_seq)) { 4431 /* We are past it -- free it */ 4432 tcp_http_log_req_info(tp, ent, 4433 i, TCP_HTTP_REQ_LOG_FREED, 0, 0); 4434 tcp_http_free_a_slot(tp, ent); 4435 ret++; 4436 } 4437 } 4438 return (ret); 4439 } 4440 4441 int 4442 tcp_http_is_entry_comp(struct tcpcb *tp, struct http_sendfile_track *ent, tcp_seq ack_point) 4443 { 4444 if (tp->t_http_req == 0) 4445 return(-1); 4446 if (tp->t_http_closed == 0) 4447 return(-1); 4448 if (ent->flags == TCP_HTTP_TRACK_FLG_EMPTY) 4449 return(-1); 4450 if (SEQ_GEQ(ack_point, ent->end_seq)) { 4451 return (1); 4452 } 4453 return (0); 4454 } 4455 4456 struct http_sendfile_track * 4457 tcp_http_find_a_req_that_is_completed_by(struct tcpcb *tp, tcp_seq th_ack, int *ip) 4458 { 4459 /* 4460 * Given an ack point (th_ack) walk through our entries and 4461 * return the first one found that th_ack goes past the 4462 * end_seq. 4463 */ 4464 struct http_sendfile_track *ent; 4465 int i; 4466 4467 if (tp->t_http_req == 0) { 4468 /* none open */ 4469 return (NULL); 4470 } 4471 for(i = 0; i < MAX_TCP_HTTP_REQ; i++) { 4472 ent = &tp->t_http_info[i]; 4473 if (ent->flags == TCP_HTTP_TRACK_FLG_EMPTY) 4474 continue; 4475 if ((ent->flags & TCP_HTTP_TRACK_FLG_OPEN) == 0) { 4476 if (SEQ_GEQ(th_ack, ent->end_seq)) { 4477 *ip = i; 4478 return (ent); 4479 } 4480 } 4481 } 4482 return (NULL); 4483 } 4484 4485 struct http_sendfile_track * 4486 tcp_http_find_req_for_seq(struct tcpcb *tp, tcp_seq seq) 4487 { 4488 struct http_sendfile_track *ent; 4489 int i; 4490 4491 if (tp->t_http_req == 0) { 4492 /* none open */ 4493 return (NULL); 4494 } 4495 for(i = 0; i < MAX_TCP_HTTP_REQ; i++) { 4496 ent = &tp->t_http_info[i]; 4497 tcp_http_log_req_info(tp, ent, i, TCP_HTTP_REQ_LOG_SEARCH, 4498 (uint64_t)seq, 0); 4499 if (ent->flags == TCP_HTTP_TRACK_FLG_EMPTY) { 4500 continue; 4501 } 4502 if (ent->flags & TCP_HTTP_TRACK_FLG_OPEN) { 4503 /* 4504 * An open end request only needs to 4505 * match the beginning seq or be 4506 * all we have (once we keep going on 4507 * a open end request we may have a seq 4508 * wrap). 4509 */ 4510 if ((SEQ_GEQ(seq, ent->start_seq)) || 4511 (tp->t_http_closed == 0)) 4512 return (ent); 4513 } else { 4514 /* 4515 * For this one we need to 4516 * be a bit more careful if its 4517 * completed at least. 4518 */ 4519 if ((SEQ_GEQ(seq, ent->start_seq)) && 4520 (SEQ_LT(seq, ent->end_seq))) { 4521 return (ent); 4522 } 4523 } 4524 } 4525 return (NULL); 4526 } 4527 4528 /* Should this be in its own file tcp_http.c ? */ 4529 struct http_sendfile_track * 4530 tcp_http_alloc_req_full(struct tcpcb *tp, struct http_req *req, uint64_t ts, int rec_dups) 4531 { 4532 struct http_sendfile_track *fil; 4533 int i, allocated; 4534 4535 /* In case the stack does not check for completions do so now */ 4536 tcp_http_check_for_comp(tp, tp->snd_una); 4537 /* Check for stale entries */ 4538 if (tp->t_http_req) 4539 tcp_http_check_for_stale_entries(tp, ts, 4540 (tp->t_http_req >= MAX_TCP_HTTP_REQ)); 4541 /* Check to see if this is a duplicate of one not started */ 4542 if (tp->t_http_req) { 4543 for(i = 0, allocated = 0; i < MAX_TCP_HTTP_REQ; i++) { 4544 fil = &tp->t_http_info[i]; 4545 if (fil->flags != TCP_HTTP_TRACK_FLG_USED) 4546 continue; 4547 if ((fil->timestamp == req->timestamp) && 4548 (fil->start == req->start) && 4549 ((fil->flags & TCP_HTTP_TRACK_FLG_OPEN) || 4550 (fil->end == req->end))) { 4551 /* 4552 * We already have this request 4553 * and it has not been started with sendfile. 4554 * This probably means the user was returned 4555 * a 4xx of some sort and its going to age 4556 * out, lets not duplicate it. 4557 */ 4558 return(fil); 4559 } 4560 } 4561 } 4562 /* Ok if there is no room at the inn we are in trouble */ 4563 if (tp->t_http_req >= MAX_TCP_HTTP_REQ) { 4564 tcp_trace_point(tp, TCP_TP_HTTP_LOG_FAIL); 4565 for(i = 0; i < MAX_TCP_HTTP_REQ; i++) { 4566 tcp_http_log_req_info(tp, &tp->t_http_info[i], 4567 i, TCP_HTTP_REQ_LOG_ALLOCFAIL, 0, 0); 4568 } 4569 return (NULL); 4570 } 4571 for(i = 0, allocated = 0; i < MAX_TCP_HTTP_REQ; i++) { 4572 fil = &tp->t_http_info[i]; 4573 if (fil->flags == TCP_HTTP_TRACK_FLG_EMPTY) { 4574 allocated = 1; 4575 fil->flags = TCP_HTTP_TRACK_FLG_USED; 4576 fil->timestamp = req->timestamp; 4577 fil->localtime = ts; 4578 fil->start = req->start; 4579 if (req->flags & TCP_LOG_HTTPD_RANGE_END) { 4580 fil->end = req->end; 4581 } else { 4582 fil->end = 0; 4583 fil->flags |= TCP_HTTP_TRACK_FLG_OPEN; 4584 } 4585 /* 4586 * We can set the min boundaries to the TCP Sequence space, 4587 * but it might be found to be further up when sendfile 4588 * actually runs on this range (if it ever does). 4589 */ 4590 fil->sbcc_at_s = tptosocket(tp)->so_snd.sb_ccc; 4591 fil->start_seq = tp->snd_una + 4592 tptosocket(tp)->so_snd.sb_ccc; 4593 fil->end_seq = (fil->start_seq + ((uint32_t)(fil->end - fil->start))); 4594 if (tptosocket(tp)->so_snd.sb_tls_info) { 4595 /* 4596 * This session is doing TLS. Take a swag guess 4597 * at the overhead. 4598 */ 4599 fil->end_seq += tcp_estimate_tls_overhead( 4600 tptosocket(tp), (fil->end - fil->start)); 4601 } 4602 tp->t_http_req++; 4603 if (fil->flags & TCP_HTTP_TRACK_FLG_OPEN) 4604 tp->t_http_open++; 4605 else 4606 tp->t_http_closed++; 4607 tcp_http_log_req_info(tp, fil, i, 4608 TCP_HTTP_REQ_LOG_NEW, 0, 0); 4609 break; 4610 } else 4611 fil = NULL; 4612 } 4613 return (fil); 4614 } 4615 4616 void 4617 tcp_http_alloc_req(struct tcpcb *tp, union tcp_log_userdata *user, uint64_t ts) 4618 { 4619 (void)tcp_http_alloc_req_full(tp, &user->http_req, ts, 1); 4620 } 4621 #endif 4622 4623 void 4624 tcp_log_socket_option(struct tcpcb *tp, uint32_t option_num, uint32_t option_val, int err) 4625 { 4626 if (tcp_bblogging_on(tp)) { 4627 struct tcp_log_buffer *l; 4628 4629 l = tcp_log_event(tp, NULL, 4630 &tptosocket(tp)->so_rcv, 4631 &tptosocket(tp)->so_snd, 4632 TCP_LOG_SOCKET_OPT, 4633 err, 0, NULL, 1, 4634 NULL, NULL, 0, NULL); 4635 if (l) { 4636 l->tlb_flex1 = option_num; 4637 l->tlb_flex2 = option_val; 4638 } 4639 } 4640 } 4641