1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)tcp_subr.c 8.2 (Berkeley) 5/24/95 32 */ 33 34 #include <sys/cdefs.h> 35 __FBSDID("$FreeBSD$"); 36 37 #include "opt_inet.h" 38 #include "opt_inet6.h" 39 #include "opt_ipsec.h" 40 #include "opt_kern_tls.h" 41 42 #include <sys/param.h> 43 #include <sys/systm.h> 44 #include <sys/arb.h> 45 #include <sys/callout.h> 46 #include <sys/eventhandler.h> 47 #ifdef TCP_HHOOK 48 #include <sys/hhook.h> 49 #endif 50 #include <sys/kernel.h> 51 #ifdef TCP_HHOOK 52 #include <sys/khelp.h> 53 #endif 54 #ifdef KERN_TLS 55 #include <sys/ktls.h> 56 #endif 57 #include <sys/qmath.h> 58 #include <sys/stats.h> 59 #include <sys/sysctl.h> 60 #include <sys/jail.h> 61 #include <sys/malloc.h> 62 #include <sys/refcount.h> 63 #include <sys/mbuf.h> 64 #include <sys/priv.h> 65 #include <sys/proc.h> 66 #include <sys/sdt.h> 67 #include <sys/socket.h> 68 #include <sys/socketvar.h> 69 #include <sys/protosw.h> 70 #include <sys/random.h> 71 72 #include <vm/uma.h> 73 74 #include <net/route.h> 75 #include <net/route/nhop.h> 76 #include <net/if.h> 77 #include <net/if_var.h> 78 #include <net/if_private.h> 79 #include <net/vnet.h> 80 81 #include <netinet/in.h> 82 #include <netinet/in_fib.h> 83 #include <netinet/in_kdtrace.h> 84 #include <netinet/in_pcb.h> 85 #include <netinet/in_systm.h> 86 #include <netinet/in_var.h> 87 #include <netinet/ip.h> 88 #include <netinet/ip_icmp.h> 89 #include <netinet/ip_var.h> 90 #ifdef INET6 91 #include <netinet/icmp6.h> 92 #include <netinet/ip6.h> 93 #include <netinet6/in6_fib.h> 94 #include <netinet6/in6_pcb.h> 95 #include <netinet6/ip6_var.h> 96 #include <netinet6/scope6_var.h> 97 #include <netinet6/nd6.h> 98 #endif 99 100 #include <netinet/tcp.h> 101 #ifdef INVARIANTS 102 #define TCPSTATES 103 #endif 104 #include <netinet/tcp_fsm.h> 105 #include <netinet/tcp_seq.h> 106 #include <netinet/tcp_timer.h> 107 #include <netinet/tcp_var.h> 108 #include <netinet/tcp_ecn.h> 109 #include <netinet/tcp_log_buf.h> 110 #include <netinet/tcp_syncache.h> 111 #include <netinet/tcp_hpts.h> 112 #include <netinet/tcp_lro.h> 113 #include <netinet/cc/cc.h> 114 #include <netinet/tcpip.h> 115 #include <netinet/tcp_fastopen.h> 116 #include <netinet/tcp_accounting.h> 117 #ifdef TCPPCAP 118 #include <netinet/tcp_pcap.h> 119 #endif 120 #ifdef TCP_OFFLOAD 121 #include <netinet/tcp_offload.h> 122 #endif 123 #include <netinet/udp.h> 124 #include <netinet/udp_var.h> 125 #ifdef INET6 126 #include <netinet6/tcp6_var.h> 127 #endif 128 129 #include <netipsec/ipsec_support.h> 130 131 #include <machine/in_cksum.h> 132 #include <crypto/siphash/siphash.h> 133 134 #include <security/mac/mac_framework.h> 135 136 #ifdef INET6 137 static ip6proto_ctlinput_t tcp6_ctlinput; 138 static udp_tun_icmp_t tcp6_ctlinput_viaudp; 139 #endif 140 141 VNET_DEFINE(int, tcp_mssdflt) = TCP_MSS; 142 #ifdef INET6 143 VNET_DEFINE(int, tcp_v6mssdflt) = TCP6_MSS; 144 #endif 145 146 #ifdef TCP_SAD_DETECTION 147 /* Sack attack detection thresholds and such */ 148 SYSCTL_NODE(_net_inet_tcp, OID_AUTO, sack_attack, 149 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 150 "Sack Attack detection thresholds"); 151 int32_t tcp_force_detection = 0; 152 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, force_detection, 153 CTLFLAG_RW, 154 &tcp_force_detection, 0, 155 "Do we force detection even if the INP has it off?"); 156 int32_t tcp_sad_limit = 10000; 157 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, limit, 158 CTLFLAG_RW, 159 &tcp_sad_limit, 10000, 160 "If SaD is enabled, what is the limit to sendmap entries (0 = unlimited)?"); 161 int32_t tcp_sack_to_ack_thresh = 700; /* 70 % */ 162 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, sack_to_ack_thresh, 163 CTLFLAG_RW, 164 &tcp_sack_to_ack_thresh, 700, 165 "Percentage of sacks to acks we must see above (10.1 percent is 101)?"); 166 int32_t tcp_sack_to_move_thresh = 600; /* 60 % */ 167 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, move_thresh, 168 CTLFLAG_RW, 169 &tcp_sack_to_move_thresh, 600, 170 "Percentage of sack moves we must see above (10.1 percent is 101)"); 171 int32_t tcp_restoral_thresh = 650; /* 65 % (sack:2:ack -5%) */ 172 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, restore_thresh, 173 CTLFLAG_RW, 174 &tcp_restoral_thresh, 550, 175 "Percentage of sack to ack percentage we must see below to restore(10.1 percent is 101)"); 176 int32_t tcp_sad_decay_val = 800; 177 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, decay_per, 178 CTLFLAG_RW, 179 &tcp_sad_decay_val, 800, 180 "The decay percentage (10.1 percent equals 101 )"); 181 int32_t tcp_map_minimum = 500; 182 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, nummaps, 183 CTLFLAG_RW, 184 &tcp_map_minimum, 500, 185 "Number of Map enteries before we start detection"); 186 int32_t tcp_sad_pacing_interval = 2000; 187 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, sad_pacing_int, 188 CTLFLAG_RW, 189 &tcp_sad_pacing_interval, 2000, 190 "What is the minimum pacing interval for a classified attacker?"); 191 192 int32_t tcp_sad_low_pps = 100; 193 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, sad_low_pps, 194 CTLFLAG_RW, 195 &tcp_sad_low_pps, 100, 196 "What is the input pps that below which we do not decay?"); 197 #endif 198 uint32_t tcp_ack_war_time_window = 1000; 199 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, ack_war_timewindow, 200 CTLFLAG_RW, 201 &tcp_ack_war_time_window, 1000, 202 "If the tcp_stack does ack-war prevention how many milliseconds are in its time window?"); 203 uint32_t tcp_ack_war_cnt = 5; 204 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, ack_war_cnt, 205 CTLFLAG_RW, 206 &tcp_ack_war_cnt, 5, 207 "If the tcp_stack does ack-war prevention how many acks can be sent in its time window?"); 208 209 struct rwlock tcp_function_lock; 210 211 static int 212 sysctl_net_inet_tcp_mss_check(SYSCTL_HANDLER_ARGS) 213 { 214 int error, new; 215 216 new = V_tcp_mssdflt; 217 error = sysctl_handle_int(oidp, &new, 0, req); 218 if (error == 0 && req->newptr) { 219 if (new < TCP_MINMSS) 220 error = EINVAL; 221 else 222 V_tcp_mssdflt = new; 223 } 224 return (error); 225 } 226 227 SYSCTL_PROC(_net_inet_tcp, TCPCTL_MSSDFLT, mssdflt, 228 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 229 &VNET_NAME(tcp_mssdflt), 0, &sysctl_net_inet_tcp_mss_check, "I", 230 "Default TCP Maximum Segment Size"); 231 232 #ifdef INET6 233 static int 234 sysctl_net_inet_tcp_mss_v6_check(SYSCTL_HANDLER_ARGS) 235 { 236 int error, new; 237 238 new = V_tcp_v6mssdflt; 239 error = sysctl_handle_int(oidp, &new, 0, req); 240 if (error == 0 && req->newptr) { 241 if (new < TCP_MINMSS) 242 error = EINVAL; 243 else 244 V_tcp_v6mssdflt = new; 245 } 246 return (error); 247 } 248 249 SYSCTL_PROC(_net_inet_tcp, TCPCTL_V6MSSDFLT, v6mssdflt, 250 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 251 &VNET_NAME(tcp_v6mssdflt), 0, &sysctl_net_inet_tcp_mss_v6_check, "I", 252 "Default TCP Maximum Segment Size for IPv6"); 253 #endif /* INET6 */ 254 255 /* 256 * Minimum MSS we accept and use. This prevents DoS attacks where 257 * we are forced to a ridiculous low MSS like 20 and send hundreds 258 * of packets instead of one. The effect scales with the available 259 * bandwidth and quickly saturates the CPU and network interface 260 * with packet generation and sending. Set to zero to disable MINMSS 261 * checking. This setting prevents us from sending too small packets. 262 */ 263 VNET_DEFINE(int, tcp_minmss) = TCP_MINMSS; 264 SYSCTL_INT(_net_inet_tcp, OID_AUTO, minmss, CTLFLAG_VNET | CTLFLAG_RW, 265 &VNET_NAME(tcp_minmss), 0, 266 "Minimum TCP Maximum Segment Size"); 267 268 VNET_DEFINE(int, tcp_do_rfc1323) = 1; 269 SYSCTL_INT(_net_inet_tcp, TCPCTL_DO_RFC1323, rfc1323, CTLFLAG_VNET | CTLFLAG_RW, 270 &VNET_NAME(tcp_do_rfc1323), 0, 271 "Enable rfc1323 (high performance TCP) extensions"); 272 273 /* 274 * As of June 2021, several TCP stacks violate RFC 7323 from September 2014. 275 * Some stacks negotiate TS, but never send them after connection setup. Some 276 * stacks negotiate TS, but don't send them when sending keep-alive segments. 277 * These include modern widely deployed TCP stacks. 278 * Therefore tolerating violations for now... 279 */ 280 VNET_DEFINE(int, tcp_tolerate_missing_ts) = 1; 281 SYSCTL_INT(_net_inet_tcp, OID_AUTO, tolerate_missing_ts, CTLFLAG_VNET | CTLFLAG_RW, 282 &VNET_NAME(tcp_tolerate_missing_ts), 0, 283 "Tolerate missing TCP timestamps"); 284 285 VNET_DEFINE(int, tcp_ts_offset_per_conn) = 1; 286 SYSCTL_INT(_net_inet_tcp, OID_AUTO, ts_offset_per_conn, CTLFLAG_VNET | CTLFLAG_RW, 287 &VNET_NAME(tcp_ts_offset_per_conn), 0, 288 "Initialize TCP timestamps per connection instead of per host pair"); 289 290 /* How many connections are pacing */ 291 static volatile uint32_t number_of_tcp_connections_pacing = 0; 292 static uint32_t shadow_num_connections = 0; 293 294 static int tcp_pacing_limit = 10000; 295 SYSCTL_INT(_net_inet_tcp, OID_AUTO, pacing_limit, CTLFLAG_RW, 296 &tcp_pacing_limit, 1000, 297 "If the TCP stack does pacing, is there a limit (-1 = no, 0 = no pacing N = number of connections)"); 298 299 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, pacing_count, CTLFLAG_RD, 300 &shadow_num_connections, 0, "Number of TCP connections being paced"); 301 302 static int tcp_log_debug = 0; 303 SYSCTL_INT(_net_inet_tcp, OID_AUTO, log_debug, CTLFLAG_RW, 304 &tcp_log_debug, 0, "Log errors caused by incoming TCP segments"); 305 306 static int tcp_tcbhashsize; 307 SYSCTL_INT(_net_inet_tcp, OID_AUTO, tcbhashsize, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, 308 &tcp_tcbhashsize, 0, "Size of TCP control-block hashtable"); 309 310 static int do_tcpdrain = 1; 311 SYSCTL_INT(_net_inet_tcp, OID_AUTO, do_tcpdrain, CTLFLAG_RW, &do_tcpdrain, 0, 312 "Enable tcp_drain routine for extra help when low on mbufs"); 313 314 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, pcbcount, CTLFLAG_VNET | CTLFLAG_RD, 315 &VNET_NAME(tcbinfo.ipi_count), 0, "Number of active PCBs"); 316 317 VNET_DEFINE_STATIC(int, icmp_may_rst) = 1; 318 #define V_icmp_may_rst VNET(icmp_may_rst) 319 SYSCTL_INT(_net_inet_tcp, OID_AUTO, icmp_may_rst, CTLFLAG_VNET | CTLFLAG_RW, 320 &VNET_NAME(icmp_may_rst), 0, 321 "Certain ICMP unreachable messages may abort connections in SYN_SENT"); 322 323 VNET_DEFINE_STATIC(int, tcp_isn_reseed_interval) = 0; 324 #define V_tcp_isn_reseed_interval VNET(tcp_isn_reseed_interval) 325 SYSCTL_INT(_net_inet_tcp, OID_AUTO, isn_reseed_interval, CTLFLAG_VNET | CTLFLAG_RW, 326 &VNET_NAME(tcp_isn_reseed_interval), 0, 327 "Seconds between reseeding of ISN secret"); 328 329 static int tcp_soreceive_stream; 330 SYSCTL_INT(_net_inet_tcp, OID_AUTO, soreceive_stream, CTLFLAG_RDTUN, 331 &tcp_soreceive_stream, 0, "Using soreceive_stream for TCP sockets"); 332 333 VNET_DEFINE(uma_zone_t, sack_hole_zone); 334 #define V_sack_hole_zone VNET(sack_hole_zone) 335 VNET_DEFINE(uint32_t, tcp_map_entries_limit) = 0; /* unlimited */ 336 static int 337 sysctl_net_inet_tcp_map_limit_check(SYSCTL_HANDLER_ARGS) 338 { 339 int error; 340 uint32_t new; 341 342 new = V_tcp_map_entries_limit; 343 error = sysctl_handle_int(oidp, &new, 0, req); 344 if (error == 0 && req->newptr) { 345 /* only allow "0" and value > minimum */ 346 if (new > 0 && new < TCP_MIN_MAP_ENTRIES_LIMIT) 347 error = EINVAL; 348 else 349 V_tcp_map_entries_limit = new; 350 } 351 return (error); 352 } 353 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, map_limit, 354 CTLFLAG_VNET | CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 355 &VNET_NAME(tcp_map_entries_limit), 0, 356 &sysctl_net_inet_tcp_map_limit_check, "IU", 357 "Total sendmap entries limit"); 358 359 VNET_DEFINE(uint32_t, tcp_map_split_limit) = 0; /* unlimited */ 360 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, split_limit, CTLFLAG_VNET | CTLFLAG_RW, 361 &VNET_NAME(tcp_map_split_limit), 0, 362 "Total sendmap split entries limit"); 363 364 #ifdef TCP_HHOOK 365 VNET_DEFINE(struct hhook_head *, tcp_hhh[HHOOK_TCP_LAST+1]); 366 #endif 367 368 #define TS_OFFSET_SECRET_LENGTH SIPHASH_KEY_LENGTH 369 VNET_DEFINE_STATIC(u_char, ts_offset_secret[TS_OFFSET_SECRET_LENGTH]); 370 #define V_ts_offset_secret VNET(ts_offset_secret) 371 372 static int tcp_default_fb_init(struct tcpcb *tp, void **ptr); 373 static void tcp_default_fb_fini(struct tcpcb *tp, int tcb_is_purged); 374 static int tcp_default_handoff_ok(struct tcpcb *tp); 375 static struct inpcb *tcp_notify(struct inpcb *, int); 376 static struct inpcb *tcp_mtudisc_notify(struct inpcb *, int); 377 static struct inpcb *tcp_mtudisc(struct inpcb *, int); 378 static struct inpcb *tcp_drop_syn_sent(struct inpcb *, int); 379 static char * tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th, 380 const void *ip4hdr, const void *ip6hdr); 381 static ipproto_ctlinput_t tcp_ctlinput; 382 static udp_tun_icmp_t tcp_ctlinput_viaudp; 383 384 static struct tcp_function_block tcp_def_funcblk = { 385 .tfb_tcp_block_name = "freebsd", 386 .tfb_tcp_output = tcp_default_output, 387 .tfb_tcp_do_segment = tcp_do_segment, 388 .tfb_tcp_ctloutput = tcp_default_ctloutput, 389 .tfb_tcp_handoff_ok = tcp_default_handoff_ok, 390 .tfb_tcp_fb_init = tcp_default_fb_init, 391 .tfb_tcp_fb_fini = tcp_default_fb_fini, 392 }; 393 394 static int tcp_fb_cnt = 0; 395 struct tcp_funchead t_functions; 396 static struct tcp_function_block *tcp_func_set_ptr = &tcp_def_funcblk; 397 398 void 399 tcp_record_dsack(struct tcpcb *tp, tcp_seq start, tcp_seq end, int tlp) 400 { 401 TCPSTAT_INC(tcps_dsack_count); 402 tp->t_dsack_pack++; 403 if (tlp == 0) { 404 if (SEQ_GT(end, start)) { 405 tp->t_dsack_bytes += (end - start); 406 TCPSTAT_ADD(tcps_dsack_bytes, (end - start)); 407 } else { 408 tp->t_dsack_tlp_bytes += (start - end); 409 TCPSTAT_ADD(tcps_dsack_bytes, (start - end)); 410 } 411 } else { 412 if (SEQ_GT(end, start)) { 413 tp->t_dsack_bytes += (end - start); 414 TCPSTAT_ADD(tcps_dsack_tlp_bytes, (end - start)); 415 } else { 416 tp->t_dsack_tlp_bytes += (start - end); 417 TCPSTAT_ADD(tcps_dsack_tlp_bytes, (start - end)); 418 } 419 } 420 } 421 422 static struct tcp_function_block * 423 find_tcp_functions_locked(struct tcp_function_set *fs) 424 { 425 struct tcp_function *f; 426 struct tcp_function_block *blk=NULL; 427 428 TAILQ_FOREACH(f, &t_functions, tf_next) { 429 if (strcmp(f->tf_name, fs->function_set_name) == 0) { 430 blk = f->tf_fb; 431 break; 432 } 433 } 434 return(blk); 435 } 436 437 static struct tcp_function_block * 438 find_tcp_fb_locked(struct tcp_function_block *blk, struct tcp_function **s) 439 { 440 struct tcp_function_block *rblk=NULL; 441 struct tcp_function *f; 442 443 TAILQ_FOREACH(f, &t_functions, tf_next) { 444 if (f->tf_fb == blk) { 445 rblk = blk; 446 if (s) { 447 *s = f; 448 } 449 break; 450 } 451 } 452 return (rblk); 453 } 454 455 struct tcp_function_block * 456 find_and_ref_tcp_functions(struct tcp_function_set *fs) 457 { 458 struct tcp_function_block *blk; 459 460 rw_rlock(&tcp_function_lock); 461 blk = find_tcp_functions_locked(fs); 462 if (blk) 463 refcount_acquire(&blk->tfb_refcnt); 464 rw_runlock(&tcp_function_lock); 465 return(blk); 466 } 467 468 struct tcp_function_block * 469 find_and_ref_tcp_fb(struct tcp_function_block *blk) 470 { 471 struct tcp_function_block *rblk; 472 473 rw_rlock(&tcp_function_lock); 474 rblk = find_tcp_fb_locked(blk, NULL); 475 if (rblk) 476 refcount_acquire(&rblk->tfb_refcnt); 477 rw_runlock(&tcp_function_lock); 478 return(rblk); 479 } 480 481 /* Find a matching alias for the given tcp_function_block. */ 482 int 483 find_tcp_function_alias(struct tcp_function_block *blk, 484 struct tcp_function_set *fs) 485 { 486 struct tcp_function *f; 487 int found; 488 489 found = 0; 490 rw_rlock(&tcp_function_lock); 491 TAILQ_FOREACH(f, &t_functions, tf_next) { 492 if ((f->tf_fb == blk) && 493 (strncmp(f->tf_name, blk->tfb_tcp_block_name, 494 TCP_FUNCTION_NAME_LEN_MAX) != 0)) { 495 /* Matching function block with different name. */ 496 strncpy(fs->function_set_name, f->tf_name, 497 TCP_FUNCTION_NAME_LEN_MAX); 498 found = 1; 499 break; 500 } 501 } 502 /* Null terminate the string appropriately. */ 503 if (found) { 504 fs->function_set_name[TCP_FUNCTION_NAME_LEN_MAX - 1] = '\0'; 505 } else { 506 fs->function_set_name[0] = '\0'; 507 } 508 rw_runlock(&tcp_function_lock); 509 return (found); 510 } 511 512 static struct tcp_function_block * 513 find_and_ref_tcp_default_fb(void) 514 { 515 struct tcp_function_block *rblk; 516 517 rw_rlock(&tcp_function_lock); 518 rblk = tcp_func_set_ptr; 519 refcount_acquire(&rblk->tfb_refcnt); 520 rw_runlock(&tcp_function_lock); 521 return (rblk); 522 } 523 524 void 525 tcp_switch_back_to_default(struct tcpcb *tp) 526 { 527 struct tcp_function_block *tfb; 528 void *ptr = NULL; 529 530 KASSERT(tp->t_fb != &tcp_def_funcblk, 531 ("%s: called by the built-in default stack", __func__)); 532 533 /* 534 * Now, we'll find a new function block to use. 535 * Start by trying the current user-selected 536 * default, unless this stack is the user-selected 537 * default. 538 */ 539 tfb = find_and_ref_tcp_default_fb(); 540 if (tfb == tp->t_fb) { 541 refcount_release(&tfb->tfb_refcnt); 542 tfb = NULL; 543 } 544 /* Does the stack accept this connection? */ 545 if (tfb != NULL && tfb->tfb_tcp_handoff_ok != NULL && 546 (*tfb->tfb_tcp_handoff_ok)(tp)) { 547 refcount_release(&tfb->tfb_refcnt); 548 tfb = NULL; 549 } 550 /* Try to use that stack. */ 551 if (tfb != NULL) { 552 /* Initialize the new stack. If it succeeds, we are done. */ 553 if (tfb->tfb_tcp_fb_init == NULL || 554 (*tfb->tfb_tcp_fb_init)(tp, &ptr) == 0) { 555 /* Release the old stack */ 556 if (tp->t_fb->tfb_tcp_fb_fini != NULL) 557 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 0); 558 refcount_release(&tp->t_fb->tfb_refcnt); 559 /* Now set in all the pointers */ 560 tp->t_fb = tfb; 561 tp->t_fb_ptr = ptr; 562 return; 563 } 564 /* 565 * Initialization failed. Release the reference count on 566 * the looked up default stack. 567 */ 568 refcount_release(&tfb->tfb_refcnt); 569 } 570 571 /* 572 * If that wasn't feasible, use the built-in default 573 * stack which is not allowed to reject anyone. 574 */ 575 tfb = find_and_ref_tcp_fb(&tcp_def_funcblk); 576 if (tfb == NULL) { 577 /* there always should be a default */ 578 panic("Can't refer to tcp_def_funcblk"); 579 } 580 if (tfb->tfb_tcp_handoff_ok != NULL) { 581 if ((*tfb->tfb_tcp_handoff_ok) (tp)) { 582 /* The default stack cannot say no */ 583 panic("Default stack rejects a new session?"); 584 } 585 } 586 if (tfb->tfb_tcp_fb_init != NULL && 587 (*tfb->tfb_tcp_fb_init)(tp, &ptr)) { 588 /* The default stack cannot fail */ 589 panic("Default stack initialization failed"); 590 } 591 /* Now release the old stack */ 592 if (tp->t_fb->tfb_tcp_fb_fini != NULL) 593 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 0); 594 refcount_release(&tp->t_fb->tfb_refcnt); 595 /* And set in the pointers to the new */ 596 tp->t_fb = tfb; 597 tp->t_fb_ptr = ptr; 598 } 599 600 static bool 601 tcp_recv_udp_tunneled_packet(struct mbuf *m, int off, struct inpcb *inp, 602 const struct sockaddr *sa, void *ctx) 603 { 604 struct ip *iph; 605 #ifdef INET6 606 struct ip6_hdr *ip6; 607 #endif 608 struct udphdr *uh; 609 struct tcphdr *th; 610 int thlen; 611 uint16_t port; 612 613 TCPSTAT_INC(tcps_tunneled_pkts); 614 if ((m->m_flags & M_PKTHDR) == 0) { 615 /* Can't handle one that is not a pkt hdr */ 616 TCPSTAT_INC(tcps_tunneled_errs); 617 goto out; 618 } 619 thlen = sizeof(struct tcphdr); 620 if (m->m_len < off + sizeof(struct udphdr) + thlen && 621 (m = m_pullup(m, off + sizeof(struct udphdr) + thlen)) == NULL) { 622 TCPSTAT_INC(tcps_tunneled_errs); 623 goto out; 624 } 625 iph = mtod(m, struct ip *); 626 uh = (struct udphdr *)((caddr_t)iph + off); 627 th = (struct tcphdr *)(uh + 1); 628 thlen = th->th_off << 2; 629 if (m->m_len < off + sizeof(struct udphdr) + thlen) { 630 m = m_pullup(m, off + sizeof(struct udphdr) + thlen); 631 if (m == NULL) { 632 TCPSTAT_INC(tcps_tunneled_errs); 633 goto out; 634 } else { 635 iph = mtod(m, struct ip *); 636 uh = (struct udphdr *)((caddr_t)iph + off); 637 th = (struct tcphdr *)(uh + 1); 638 } 639 } 640 m->m_pkthdr.tcp_tun_port = port = uh->uh_sport; 641 bcopy(th, uh, m->m_len - off); 642 m->m_len -= sizeof(struct udphdr); 643 m->m_pkthdr.len -= sizeof(struct udphdr); 644 /* 645 * We use the same algorithm for 646 * both UDP and TCP for c-sum. So 647 * the code in tcp_input will skip 648 * the checksum. So we do nothing 649 * with the flag (m->m_pkthdr.csum_flags). 650 */ 651 switch (iph->ip_v) { 652 #ifdef INET 653 case IPVERSION: 654 iph->ip_len = htons(ntohs(iph->ip_len) - sizeof(struct udphdr)); 655 tcp_input_with_port(&m, &off, IPPROTO_TCP, port); 656 break; 657 #endif 658 #ifdef INET6 659 case IPV6_VERSION >> 4: 660 ip6 = mtod(m, struct ip6_hdr *); 661 ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - sizeof(struct udphdr)); 662 tcp6_input_with_port(&m, &off, IPPROTO_TCP, port); 663 break; 664 #endif 665 default: 666 goto out; 667 break; 668 } 669 return (true); 670 out: 671 m_freem(m); 672 673 return (true); 674 } 675 676 static int 677 sysctl_net_inet_default_tcp_functions(SYSCTL_HANDLER_ARGS) 678 { 679 int error=ENOENT; 680 struct tcp_function_set fs; 681 struct tcp_function_block *blk; 682 683 memset(&fs, 0, sizeof(fs)); 684 rw_rlock(&tcp_function_lock); 685 blk = find_tcp_fb_locked(tcp_func_set_ptr, NULL); 686 if (blk) { 687 /* Found him */ 688 strcpy(fs.function_set_name, blk->tfb_tcp_block_name); 689 fs.pcbcnt = blk->tfb_refcnt; 690 } 691 rw_runlock(&tcp_function_lock); 692 error = sysctl_handle_string(oidp, fs.function_set_name, 693 sizeof(fs.function_set_name), req); 694 695 /* Check for error or no change */ 696 if (error != 0 || req->newptr == NULL) 697 return(error); 698 699 rw_wlock(&tcp_function_lock); 700 blk = find_tcp_functions_locked(&fs); 701 if ((blk == NULL) || 702 (blk->tfb_flags & TCP_FUNC_BEING_REMOVED)) { 703 error = ENOENT; 704 goto done; 705 } 706 tcp_func_set_ptr = blk; 707 done: 708 rw_wunlock(&tcp_function_lock); 709 return (error); 710 } 711 712 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, functions_default, 713 CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 714 NULL, 0, sysctl_net_inet_default_tcp_functions, "A", 715 "Set/get the default TCP functions"); 716 717 static int 718 sysctl_net_inet_list_available(SYSCTL_HANDLER_ARGS) 719 { 720 int error, cnt, linesz; 721 struct tcp_function *f; 722 char *buffer, *cp; 723 size_t bufsz, outsz; 724 bool alias; 725 726 cnt = 0; 727 rw_rlock(&tcp_function_lock); 728 TAILQ_FOREACH(f, &t_functions, tf_next) { 729 cnt++; 730 } 731 rw_runlock(&tcp_function_lock); 732 733 bufsz = (cnt+2) * ((TCP_FUNCTION_NAME_LEN_MAX * 2) + 13) + 1; 734 buffer = malloc(bufsz, M_TEMP, M_WAITOK); 735 736 error = 0; 737 cp = buffer; 738 739 linesz = snprintf(cp, bufsz, "\n%-32s%c %-32s %s\n", "Stack", 'D', 740 "Alias", "PCB count"); 741 cp += linesz; 742 bufsz -= linesz; 743 outsz = linesz; 744 745 rw_rlock(&tcp_function_lock); 746 TAILQ_FOREACH(f, &t_functions, tf_next) { 747 alias = (f->tf_name != f->tf_fb->tfb_tcp_block_name); 748 linesz = snprintf(cp, bufsz, "%-32s%c %-32s %u\n", 749 f->tf_fb->tfb_tcp_block_name, 750 (f->tf_fb == tcp_func_set_ptr) ? '*' : ' ', 751 alias ? f->tf_name : "-", 752 f->tf_fb->tfb_refcnt); 753 if (linesz >= bufsz) { 754 error = EOVERFLOW; 755 break; 756 } 757 cp += linesz; 758 bufsz -= linesz; 759 outsz += linesz; 760 } 761 rw_runlock(&tcp_function_lock); 762 if (error == 0) 763 error = sysctl_handle_string(oidp, buffer, outsz + 1, req); 764 free(buffer, M_TEMP); 765 return (error); 766 } 767 768 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, functions_available, 769 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT, 770 NULL, 0, sysctl_net_inet_list_available, "A", 771 "list available TCP Function sets"); 772 773 VNET_DEFINE(int, tcp_udp_tunneling_port) = TCP_TUNNELING_PORT_DEFAULT; 774 775 #ifdef INET 776 VNET_DEFINE(struct socket *, udp4_tun_socket) = NULL; 777 #define V_udp4_tun_socket VNET(udp4_tun_socket) 778 #endif 779 #ifdef INET6 780 VNET_DEFINE(struct socket *, udp6_tun_socket) = NULL; 781 #define V_udp6_tun_socket VNET(udp6_tun_socket) 782 #endif 783 784 static struct sx tcpoudp_lock; 785 786 static void 787 tcp_over_udp_stop(void) 788 { 789 790 sx_assert(&tcpoudp_lock, SA_XLOCKED); 791 792 #ifdef INET 793 if (V_udp4_tun_socket != NULL) { 794 soclose(V_udp4_tun_socket); 795 V_udp4_tun_socket = NULL; 796 } 797 #endif 798 #ifdef INET6 799 if (V_udp6_tun_socket != NULL) { 800 soclose(V_udp6_tun_socket); 801 V_udp6_tun_socket = NULL; 802 } 803 #endif 804 } 805 806 static int 807 tcp_over_udp_start(void) 808 { 809 uint16_t port; 810 int ret; 811 #ifdef INET 812 struct sockaddr_in sin; 813 #endif 814 #ifdef INET6 815 struct sockaddr_in6 sin6; 816 #endif 817 818 sx_assert(&tcpoudp_lock, SA_XLOCKED); 819 820 port = V_tcp_udp_tunneling_port; 821 if (ntohs(port) == 0) { 822 /* Must have a port set */ 823 return (EINVAL); 824 } 825 #ifdef INET 826 if (V_udp4_tun_socket != NULL) { 827 /* Already running -- must stop first */ 828 return (EALREADY); 829 } 830 #endif 831 #ifdef INET6 832 if (V_udp6_tun_socket != NULL) { 833 /* Already running -- must stop first */ 834 return (EALREADY); 835 } 836 #endif 837 #ifdef INET 838 if ((ret = socreate(PF_INET, &V_udp4_tun_socket, 839 SOCK_DGRAM, IPPROTO_UDP, 840 curthread->td_ucred, curthread))) { 841 tcp_over_udp_stop(); 842 return (ret); 843 } 844 /* Call the special UDP hook. */ 845 if ((ret = udp_set_kernel_tunneling(V_udp4_tun_socket, 846 tcp_recv_udp_tunneled_packet, 847 tcp_ctlinput_viaudp, 848 NULL))) { 849 tcp_over_udp_stop(); 850 return (ret); 851 } 852 /* Ok, we have a socket, bind it to the port. */ 853 memset(&sin, 0, sizeof(struct sockaddr_in)); 854 sin.sin_len = sizeof(struct sockaddr_in); 855 sin.sin_family = AF_INET; 856 sin.sin_port = htons(port); 857 if ((ret = sobind(V_udp4_tun_socket, 858 (struct sockaddr *)&sin, curthread))) { 859 tcp_over_udp_stop(); 860 return (ret); 861 } 862 #endif 863 #ifdef INET6 864 if ((ret = socreate(PF_INET6, &V_udp6_tun_socket, 865 SOCK_DGRAM, IPPROTO_UDP, 866 curthread->td_ucred, curthread))) { 867 tcp_over_udp_stop(); 868 return (ret); 869 } 870 /* Call the special UDP hook. */ 871 if ((ret = udp_set_kernel_tunneling(V_udp6_tun_socket, 872 tcp_recv_udp_tunneled_packet, 873 tcp6_ctlinput_viaudp, 874 NULL))) { 875 tcp_over_udp_stop(); 876 return (ret); 877 } 878 /* Ok, we have a socket, bind it to the port. */ 879 memset(&sin6, 0, sizeof(struct sockaddr_in6)); 880 sin6.sin6_len = sizeof(struct sockaddr_in6); 881 sin6.sin6_family = AF_INET6; 882 sin6.sin6_port = htons(port); 883 if ((ret = sobind(V_udp6_tun_socket, 884 (struct sockaddr *)&sin6, curthread))) { 885 tcp_over_udp_stop(); 886 return (ret); 887 } 888 #endif 889 return (0); 890 } 891 892 static int 893 sysctl_net_inet_tcp_udp_tunneling_port_check(SYSCTL_HANDLER_ARGS) 894 { 895 int error; 896 uint32_t old, new; 897 898 old = V_tcp_udp_tunneling_port; 899 new = old; 900 error = sysctl_handle_int(oidp, &new, 0, req); 901 if ((error == 0) && 902 (req->newptr != NULL)) { 903 if ((new < TCP_TUNNELING_PORT_MIN) || 904 (new > TCP_TUNNELING_PORT_MAX)) { 905 error = EINVAL; 906 } else { 907 sx_xlock(&tcpoudp_lock); 908 V_tcp_udp_tunneling_port = new; 909 if (old != 0) { 910 tcp_over_udp_stop(); 911 } 912 if (new != 0) { 913 error = tcp_over_udp_start(); 914 if (error != 0) { 915 V_tcp_udp_tunneling_port = 0; 916 } 917 } 918 sx_xunlock(&tcpoudp_lock); 919 } 920 } 921 return (error); 922 } 923 924 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, udp_tunneling_port, 925 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 926 &VNET_NAME(tcp_udp_tunneling_port), 927 0, &sysctl_net_inet_tcp_udp_tunneling_port_check, "IU", 928 "Tunneling port for tcp over udp"); 929 930 VNET_DEFINE(int, tcp_udp_tunneling_overhead) = TCP_TUNNELING_OVERHEAD_DEFAULT; 931 932 static int 933 sysctl_net_inet_tcp_udp_tunneling_overhead_check(SYSCTL_HANDLER_ARGS) 934 { 935 int error, new; 936 937 new = V_tcp_udp_tunneling_overhead; 938 error = sysctl_handle_int(oidp, &new, 0, req); 939 if (error == 0 && req->newptr) { 940 if ((new < TCP_TUNNELING_OVERHEAD_MIN) || 941 (new > TCP_TUNNELING_OVERHEAD_MAX)) 942 error = EINVAL; 943 else 944 V_tcp_udp_tunneling_overhead = new; 945 } 946 return (error); 947 } 948 949 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, udp_tunneling_overhead, 950 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 951 &VNET_NAME(tcp_udp_tunneling_overhead), 952 0, &sysctl_net_inet_tcp_udp_tunneling_overhead_check, "IU", 953 "MSS reduction when using tcp over udp"); 954 955 /* 956 * Exports one (struct tcp_function_info) for each alias/name. 957 */ 958 static int 959 sysctl_net_inet_list_func_info(SYSCTL_HANDLER_ARGS) 960 { 961 int cnt, error; 962 struct tcp_function *f; 963 struct tcp_function_info tfi; 964 965 /* 966 * We don't allow writes. 967 */ 968 if (req->newptr != NULL) 969 return (EINVAL); 970 971 /* 972 * Wire the old buffer so we can directly copy the functions to 973 * user space without dropping the lock. 974 */ 975 if (req->oldptr != NULL) { 976 error = sysctl_wire_old_buffer(req, 0); 977 if (error) 978 return (error); 979 } 980 981 /* 982 * Walk the list and copy out matching entries. If INVARIANTS 983 * is compiled in, also walk the list to verify the length of 984 * the list matches what we have recorded. 985 */ 986 rw_rlock(&tcp_function_lock); 987 988 cnt = 0; 989 #ifndef INVARIANTS 990 if (req->oldptr == NULL) { 991 cnt = tcp_fb_cnt; 992 goto skip_loop; 993 } 994 #endif 995 TAILQ_FOREACH(f, &t_functions, tf_next) { 996 #ifdef INVARIANTS 997 cnt++; 998 #endif 999 if (req->oldptr != NULL) { 1000 bzero(&tfi, sizeof(tfi)); 1001 tfi.tfi_refcnt = f->tf_fb->tfb_refcnt; 1002 tfi.tfi_id = f->tf_fb->tfb_id; 1003 (void)strlcpy(tfi.tfi_alias, f->tf_name, 1004 sizeof(tfi.tfi_alias)); 1005 (void)strlcpy(tfi.tfi_name, 1006 f->tf_fb->tfb_tcp_block_name, sizeof(tfi.tfi_name)); 1007 error = SYSCTL_OUT(req, &tfi, sizeof(tfi)); 1008 /* 1009 * Don't stop on error, as that is the 1010 * mechanism we use to accumulate length 1011 * information if the buffer was too short. 1012 */ 1013 } 1014 } 1015 KASSERT(cnt == tcp_fb_cnt, 1016 ("%s: cnt (%d) != tcp_fb_cnt (%d)", __func__, cnt, tcp_fb_cnt)); 1017 #ifndef INVARIANTS 1018 skip_loop: 1019 #endif 1020 rw_runlock(&tcp_function_lock); 1021 if (req->oldptr == NULL) 1022 error = SYSCTL_OUT(req, NULL, 1023 (cnt + 1) * sizeof(struct tcp_function_info)); 1024 1025 return (error); 1026 } 1027 1028 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, function_info, 1029 CTLTYPE_OPAQUE | CTLFLAG_SKIP | CTLFLAG_RD | CTLFLAG_MPSAFE, 1030 NULL, 0, sysctl_net_inet_list_func_info, "S,tcp_function_info", 1031 "List TCP function block name-to-ID mappings"); 1032 1033 /* 1034 * tfb_tcp_handoff_ok() function for the default stack. 1035 * Note that we'll basically try to take all comers. 1036 */ 1037 static int 1038 tcp_default_handoff_ok(struct tcpcb *tp) 1039 { 1040 1041 return (0); 1042 } 1043 1044 /* 1045 * tfb_tcp_fb_init() function for the default stack. 1046 * 1047 * This handles making sure we have appropriate timers set if you are 1048 * transitioning a socket that has some amount of setup done. 1049 * 1050 * The init() fuction from the default can *never* return non-zero i.e. 1051 * it is required to always succeed since it is the stack of last resort! 1052 */ 1053 static int 1054 tcp_default_fb_init(struct tcpcb *tp, void **ptr) 1055 { 1056 struct socket *so = tptosocket(tp); 1057 int rexmt; 1058 1059 INP_WLOCK_ASSERT(tptoinpcb(tp)); 1060 /* We don't use the pointer */ 1061 *ptr = NULL; 1062 1063 KASSERT(tp->t_state >= 0 && tp->t_state < TCPS_TIME_WAIT, 1064 ("%s: connection %p in unexpected state %d", __func__, tp, 1065 tp->t_state)); 1066 1067 /* Make sure we get no interesting mbuf queuing behavior */ 1068 /* All mbuf queue/ack compress flags should be off */ 1069 tcp_lro_features_off(tptoinpcb(tp)); 1070 1071 /* Cancel the GP measurement in progress */ 1072 tp->t_flags &= ~TF_GPUTINPROG; 1073 /* Validate the timers are not in usec, if they are convert */ 1074 tcp_change_time_units(tp, TCP_TMR_GRANULARITY_TICKS); 1075 if ((tp->t_state == TCPS_SYN_SENT) || 1076 (tp->t_state == TCPS_SYN_RECEIVED)) 1077 rexmt = tcp_rexmit_initial * tcp_backoff[tp->t_rxtshift]; 1078 else 1079 rexmt = TCP_REXMTVAL(tp) * tcp_backoff[tp->t_rxtshift]; 1080 if (tp->t_rxtshift == 0) 1081 tp->t_rxtcur = rexmt; 1082 else 1083 TCPT_RANGESET(tp->t_rxtcur, rexmt, tp->t_rttmin, TCPTV_REXMTMAX); 1084 1085 /* 1086 * Nothing to do for ESTABLISHED or LISTEN states. And, we don't 1087 * know what to do for unexpected states (which includes TIME_WAIT). 1088 */ 1089 if (tp->t_state <= TCPS_LISTEN || tp->t_state >= TCPS_TIME_WAIT) 1090 return (0); 1091 1092 /* 1093 * Make sure some kind of transmission timer is set if there is 1094 * outstanding data. 1095 */ 1096 if ((!TCPS_HAVEESTABLISHED(tp->t_state) || sbavail(&so->so_snd) || 1097 tp->snd_una != tp->snd_max) && !(tcp_timer_active(tp, TT_REXMT) || 1098 tcp_timer_active(tp, TT_PERSIST))) { 1099 /* 1100 * If the session has established and it looks like it should 1101 * be in the persist state, set the persist timer. Otherwise, 1102 * set the retransmit timer. 1103 */ 1104 if (TCPS_HAVEESTABLISHED(tp->t_state) && tp->snd_wnd == 0 && 1105 (int32_t)(tp->snd_nxt - tp->snd_una) < 1106 (int32_t)sbavail(&so->so_snd)) 1107 tcp_setpersist(tp); 1108 else 1109 tcp_timer_activate(tp, TT_REXMT, tp->t_rxtcur); 1110 } 1111 1112 /* All non-embryonic sessions get a keepalive timer. */ 1113 if (!tcp_timer_active(tp, TT_KEEP)) 1114 tcp_timer_activate(tp, TT_KEEP, 1115 TCPS_HAVEESTABLISHED(tp->t_state) ? TP_KEEPIDLE(tp) : 1116 TP_KEEPINIT(tp)); 1117 1118 /* 1119 * Make sure critical variables are initialized 1120 * if transitioning while in Recovery. 1121 */ 1122 if IN_FASTRECOVERY(tp->t_flags) { 1123 if (tp->sackhint.recover_fs == 0) 1124 tp->sackhint.recover_fs = max(1, 1125 tp->snd_nxt - tp->snd_una); 1126 } 1127 1128 return (0); 1129 } 1130 1131 /* 1132 * tfb_tcp_fb_fini() function for the default stack. 1133 * 1134 * This changes state as necessary (or prudent) to prepare for another stack 1135 * to assume responsibility for the connection. 1136 */ 1137 static void 1138 tcp_default_fb_fini(struct tcpcb *tp, int tcb_is_purged) 1139 { 1140 1141 INP_WLOCK_ASSERT(tptoinpcb(tp)); 1142 } 1143 1144 /* 1145 * Target size of TCP PCB hash tables. Must be a power of two. 1146 * 1147 * Note that this can be overridden by the kernel environment 1148 * variable net.inet.tcp.tcbhashsize 1149 */ 1150 #ifndef TCBHASHSIZE 1151 #define TCBHASHSIZE 0 1152 #endif 1153 1154 MALLOC_DEFINE(M_TCPLOG, "tcplog", "TCP address and flags print buffers"); 1155 MALLOC_DEFINE(M_TCPFUNCTIONS, "tcpfunc", "TCP function set memory"); 1156 1157 static struct mtx isn_mtx; 1158 1159 #define ISN_LOCK_INIT() mtx_init(&isn_mtx, "isn_mtx", NULL, MTX_DEF) 1160 #define ISN_LOCK() mtx_lock(&isn_mtx) 1161 #define ISN_UNLOCK() mtx_unlock(&isn_mtx) 1162 1163 INPCBSTORAGE_DEFINE(tcpcbstor, tcpcb, "tcpinp", "tcp_inpcb", "tcp", "tcphash"); 1164 1165 /* 1166 * Take a value and get the next power of 2 that doesn't overflow. 1167 * Used to size the tcp_inpcb hash buckets. 1168 */ 1169 static int 1170 maketcp_hashsize(int size) 1171 { 1172 int hashsize; 1173 1174 /* 1175 * auto tune. 1176 * get the next power of 2 higher than maxsockets. 1177 */ 1178 hashsize = 1 << fls(size); 1179 /* catch overflow, and just go one power of 2 smaller */ 1180 if (hashsize < size) { 1181 hashsize = 1 << (fls(size) - 1); 1182 } 1183 return (hashsize); 1184 } 1185 1186 static volatile int next_tcp_stack_id = 1; 1187 1188 /* 1189 * Register a TCP function block with the name provided in the names 1190 * array. (Note that this function does NOT automatically register 1191 * blk->tfb_tcp_block_name as a stack name. Therefore, you should 1192 * explicitly include blk->tfb_tcp_block_name in the list of names if 1193 * you wish to register the stack with that name.) 1194 * 1195 * Either all name registrations will succeed or all will fail. If 1196 * a name registration fails, the function will update the num_names 1197 * argument to point to the array index of the name that encountered 1198 * the failure. 1199 * 1200 * Returns 0 on success, or an error code on failure. 1201 */ 1202 int 1203 register_tcp_functions_as_names(struct tcp_function_block *blk, int wait, 1204 const char *names[], int *num_names) 1205 { 1206 struct tcp_function *n; 1207 struct tcp_function_set fs; 1208 int error, i; 1209 1210 KASSERT(names != NULL && *num_names > 0, 1211 ("%s: Called with 0-length name list", __func__)); 1212 KASSERT(names != NULL, ("%s: Called with NULL name list", __func__)); 1213 KASSERT(rw_initialized(&tcp_function_lock), 1214 ("%s: called too early", __func__)); 1215 1216 if ((blk->tfb_tcp_output == NULL) || 1217 (blk->tfb_tcp_do_segment == NULL) || 1218 (blk->tfb_tcp_ctloutput == NULL) || 1219 (strlen(blk->tfb_tcp_block_name) == 0)) { 1220 /* 1221 * These functions are required and you 1222 * need a name. 1223 */ 1224 *num_names = 0; 1225 return (EINVAL); 1226 } 1227 1228 if (blk->tfb_flags & TCP_FUNC_BEING_REMOVED) { 1229 *num_names = 0; 1230 return (EINVAL); 1231 } 1232 1233 refcount_init(&blk->tfb_refcnt, 0); 1234 blk->tfb_id = atomic_fetchadd_int(&next_tcp_stack_id, 1); 1235 for (i = 0; i < *num_names; i++) { 1236 n = malloc(sizeof(struct tcp_function), M_TCPFUNCTIONS, wait); 1237 if (n == NULL) { 1238 error = ENOMEM; 1239 goto cleanup; 1240 } 1241 n->tf_fb = blk; 1242 1243 (void)strlcpy(fs.function_set_name, names[i], 1244 sizeof(fs.function_set_name)); 1245 rw_wlock(&tcp_function_lock); 1246 if (find_tcp_functions_locked(&fs) != NULL) { 1247 /* Duplicate name space not allowed */ 1248 rw_wunlock(&tcp_function_lock); 1249 free(n, M_TCPFUNCTIONS); 1250 error = EALREADY; 1251 goto cleanup; 1252 } 1253 (void)strlcpy(n->tf_name, names[i], sizeof(n->tf_name)); 1254 TAILQ_INSERT_TAIL(&t_functions, n, tf_next); 1255 tcp_fb_cnt++; 1256 rw_wunlock(&tcp_function_lock); 1257 } 1258 return(0); 1259 1260 cleanup: 1261 /* 1262 * Deregister the names we just added. Because registration failed 1263 * for names[i], we don't need to deregister that name. 1264 */ 1265 *num_names = i; 1266 rw_wlock(&tcp_function_lock); 1267 while (--i >= 0) { 1268 TAILQ_FOREACH(n, &t_functions, tf_next) { 1269 if (!strncmp(n->tf_name, names[i], 1270 TCP_FUNCTION_NAME_LEN_MAX)) { 1271 TAILQ_REMOVE(&t_functions, n, tf_next); 1272 tcp_fb_cnt--; 1273 n->tf_fb = NULL; 1274 free(n, M_TCPFUNCTIONS); 1275 break; 1276 } 1277 } 1278 } 1279 rw_wunlock(&tcp_function_lock); 1280 return (error); 1281 } 1282 1283 /* 1284 * Register a TCP function block using the name provided in the name 1285 * argument. 1286 * 1287 * Returns 0 on success, or an error code on failure. 1288 */ 1289 int 1290 register_tcp_functions_as_name(struct tcp_function_block *blk, const char *name, 1291 int wait) 1292 { 1293 const char *name_list[1]; 1294 int num_names, rv; 1295 1296 num_names = 1; 1297 if (name != NULL) 1298 name_list[0] = name; 1299 else 1300 name_list[0] = blk->tfb_tcp_block_name; 1301 rv = register_tcp_functions_as_names(blk, wait, name_list, &num_names); 1302 return (rv); 1303 } 1304 1305 /* 1306 * Register a TCP function block using the name defined in 1307 * blk->tfb_tcp_block_name. 1308 * 1309 * Returns 0 on success, or an error code on failure. 1310 */ 1311 int 1312 register_tcp_functions(struct tcp_function_block *blk, int wait) 1313 { 1314 1315 return (register_tcp_functions_as_name(blk, NULL, wait)); 1316 } 1317 1318 /* 1319 * Deregister all names associated with a function block. This 1320 * functionally removes the function block from use within the system. 1321 * 1322 * When called with a true quiesce argument, mark the function block 1323 * as being removed so no more stacks will use it and determine 1324 * whether the removal would succeed. 1325 * 1326 * When called with a false quiesce argument, actually attempt the 1327 * removal. 1328 * 1329 * When called with a force argument, attempt to switch all TCBs to 1330 * use the default stack instead of returning EBUSY. 1331 * 1332 * Returns 0 on success (or if the removal would succeed, or an error 1333 * code on failure. 1334 */ 1335 int 1336 deregister_tcp_functions(struct tcp_function_block *blk, bool quiesce, 1337 bool force) 1338 { 1339 struct tcp_function *f; 1340 1341 if (blk == &tcp_def_funcblk) { 1342 /* You can't un-register the default */ 1343 return (EPERM); 1344 } 1345 rw_wlock(&tcp_function_lock); 1346 if (blk == tcp_func_set_ptr) { 1347 /* You can't free the current default */ 1348 rw_wunlock(&tcp_function_lock); 1349 return (EBUSY); 1350 } 1351 /* Mark the block so no more stacks can use it. */ 1352 blk->tfb_flags |= TCP_FUNC_BEING_REMOVED; 1353 /* 1354 * If TCBs are still attached to the stack, attempt to switch them 1355 * to the default stack. 1356 */ 1357 if (force && blk->tfb_refcnt) { 1358 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, 1359 INPLOOKUP_WLOCKPCB); 1360 struct inpcb *inp; 1361 struct tcpcb *tp; 1362 VNET_ITERATOR_DECL(vnet_iter); 1363 1364 rw_wunlock(&tcp_function_lock); 1365 1366 VNET_LIST_RLOCK(); 1367 VNET_FOREACH(vnet_iter) { 1368 CURVNET_SET(vnet_iter); 1369 while ((inp = inp_next(&inpi)) != NULL) { 1370 tp = intotcpcb(inp); 1371 if (tp == NULL || tp->t_fb != blk) 1372 continue; 1373 tcp_switch_back_to_default(tp); 1374 } 1375 CURVNET_RESTORE(); 1376 } 1377 VNET_LIST_RUNLOCK(); 1378 1379 rw_wlock(&tcp_function_lock); 1380 } 1381 if (blk->tfb_refcnt) { 1382 /* TCBs still attached. */ 1383 rw_wunlock(&tcp_function_lock); 1384 return (EBUSY); 1385 } 1386 if (quiesce) { 1387 /* Skip removal. */ 1388 rw_wunlock(&tcp_function_lock); 1389 return (0); 1390 } 1391 /* Remove any function names that map to this function block. */ 1392 while (find_tcp_fb_locked(blk, &f) != NULL) { 1393 TAILQ_REMOVE(&t_functions, f, tf_next); 1394 tcp_fb_cnt--; 1395 f->tf_fb = NULL; 1396 free(f, M_TCPFUNCTIONS); 1397 } 1398 rw_wunlock(&tcp_function_lock); 1399 return (0); 1400 } 1401 1402 static void 1403 tcp_drain(void) 1404 { 1405 struct epoch_tracker et; 1406 VNET_ITERATOR_DECL(vnet_iter); 1407 1408 if (!do_tcpdrain) 1409 return; 1410 1411 NET_EPOCH_ENTER(et); 1412 VNET_LIST_RLOCK_NOSLEEP(); 1413 VNET_FOREACH(vnet_iter) { 1414 CURVNET_SET(vnet_iter); 1415 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, 1416 INPLOOKUP_WLOCKPCB); 1417 struct inpcb *inpb; 1418 struct tcpcb *tcpb; 1419 1420 /* 1421 * Walk the tcpbs, if existing, and flush the reassembly queue, 1422 * if there is one... 1423 * XXX: The "Net/3" implementation doesn't imply that the TCP 1424 * reassembly queue should be flushed, but in a situation 1425 * where we're really low on mbufs, this is potentially 1426 * useful. 1427 */ 1428 while ((inpb = inp_next(&inpi)) != NULL) { 1429 if ((tcpb = intotcpcb(inpb)) != NULL) { 1430 tcp_reass_flush(tcpb); 1431 tcp_clean_sackreport(tcpb); 1432 #ifdef TCP_BLACKBOX 1433 tcp_log_drain(tcpb); 1434 #endif 1435 #ifdef TCPPCAP 1436 if (tcp_pcap_aggressive_free) { 1437 /* Free the TCP PCAP queues. */ 1438 tcp_pcap_drain(&(tcpb->t_inpkts)); 1439 tcp_pcap_drain(&(tcpb->t_outpkts)); 1440 } 1441 #endif 1442 } 1443 } 1444 CURVNET_RESTORE(); 1445 } 1446 VNET_LIST_RUNLOCK_NOSLEEP(); 1447 NET_EPOCH_EXIT(et); 1448 } 1449 1450 static void 1451 tcp_vnet_init(void *arg __unused) 1452 { 1453 1454 #ifdef TCP_HHOOK 1455 if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN, 1456 &V_tcp_hhh[HHOOK_TCP_EST_IN], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0) 1457 printf("%s: WARNING: unable to register helper hook\n", __func__); 1458 if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT, 1459 &V_tcp_hhh[HHOOK_TCP_EST_OUT], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0) 1460 printf("%s: WARNING: unable to register helper hook\n", __func__); 1461 #endif 1462 #ifdef STATS 1463 if (tcp_stats_init()) 1464 printf("%s: WARNING: unable to initialise TCP stats\n", 1465 __func__); 1466 #endif 1467 in_pcbinfo_init(&V_tcbinfo, &tcpcbstor, tcp_tcbhashsize, 1468 tcp_tcbhashsize); 1469 1470 syncache_init(); 1471 tcp_hc_init(); 1472 1473 TUNABLE_INT_FETCH("net.inet.tcp.sack.enable", &V_tcp_do_sack); 1474 V_sack_hole_zone = uma_zcreate("sackhole", sizeof(struct sackhole), 1475 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 1476 1477 tcp_fastopen_init(); 1478 1479 COUNTER_ARRAY_ALLOC(V_tcps_states, TCP_NSTATES, M_WAITOK); 1480 VNET_PCPUSTAT_ALLOC(tcpstat, M_WAITOK); 1481 1482 V_tcp_msl = TCPTV_MSL; 1483 } 1484 VNET_SYSINIT(tcp_vnet_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, 1485 tcp_vnet_init, NULL); 1486 1487 static void 1488 tcp_init(void *arg __unused) 1489 { 1490 const char *tcbhash_tuneable; 1491 int hashsize; 1492 1493 tcp_reass_global_init(); 1494 1495 /* XXX virtualize those below? */ 1496 tcp_delacktime = TCPTV_DELACK; 1497 tcp_keepinit = TCPTV_KEEP_INIT; 1498 tcp_keepidle = TCPTV_KEEP_IDLE; 1499 tcp_keepintvl = TCPTV_KEEPINTVL; 1500 tcp_maxpersistidle = TCPTV_KEEP_IDLE; 1501 tcp_rexmit_initial = TCPTV_RTOBASE; 1502 if (tcp_rexmit_initial < 1) 1503 tcp_rexmit_initial = 1; 1504 tcp_rexmit_min = TCPTV_MIN; 1505 if (tcp_rexmit_min < 1) 1506 tcp_rexmit_min = 1; 1507 tcp_persmin = TCPTV_PERSMIN; 1508 tcp_persmax = TCPTV_PERSMAX; 1509 tcp_rexmit_slop = TCPTV_CPU_VAR; 1510 tcp_finwait2_timeout = TCPTV_FINWAIT2_TIMEOUT; 1511 1512 /* Setup the tcp function block list */ 1513 TAILQ_INIT(&t_functions); 1514 rw_init(&tcp_function_lock, "tcp_func_lock"); 1515 register_tcp_functions(&tcp_def_funcblk, M_WAITOK); 1516 sx_init(&tcpoudp_lock, "TCP over UDP configuration"); 1517 #ifdef TCP_BLACKBOX 1518 /* Initialize the TCP logging data. */ 1519 tcp_log_init(); 1520 #endif 1521 arc4rand(&V_ts_offset_secret, sizeof(V_ts_offset_secret), 0); 1522 1523 if (tcp_soreceive_stream) { 1524 #ifdef INET 1525 tcp_protosw.pr_soreceive = soreceive_stream; 1526 #endif 1527 #ifdef INET6 1528 tcp6_protosw.pr_soreceive = soreceive_stream; 1529 #endif /* INET6 */ 1530 } 1531 1532 #ifdef INET6 1533 max_protohdr_grow(sizeof(struct ip6_hdr) + sizeof(struct tcphdr)); 1534 #else /* INET6 */ 1535 max_protohdr_grow(sizeof(struct tcpiphdr)); 1536 #endif /* INET6 */ 1537 1538 ISN_LOCK_INIT(); 1539 EVENTHANDLER_REGISTER(shutdown_pre_sync, tcp_fini, NULL, 1540 SHUTDOWN_PRI_DEFAULT); 1541 EVENTHANDLER_REGISTER(vm_lowmem, tcp_drain, NULL, LOWMEM_PRI_DEFAULT); 1542 EVENTHANDLER_REGISTER(mbuf_lowmem, tcp_drain, NULL, LOWMEM_PRI_DEFAULT); 1543 1544 tcp_inp_lro_direct_queue = counter_u64_alloc(M_WAITOK); 1545 tcp_inp_lro_wokeup_queue = counter_u64_alloc(M_WAITOK); 1546 tcp_inp_lro_compressed = counter_u64_alloc(M_WAITOK); 1547 tcp_inp_lro_locks_taken = counter_u64_alloc(M_WAITOK); 1548 tcp_extra_mbuf = counter_u64_alloc(M_WAITOK); 1549 tcp_would_have_but = counter_u64_alloc(M_WAITOK); 1550 tcp_comp_total = counter_u64_alloc(M_WAITOK); 1551 tcp_uncomp_total = counter_u64_alloc(M_WAITOK); 1552 tcp_bad_csums = counter_u64_alloc(M_WAITOK); 1553 #ifdef TCPPCAP 1554 tcp_pcap_init(); 1555 #endif 1556 1557 hashsize = TCBHASHSIZE; 1558 tcbhash_tuneable = "net.inet.tcp.tcbhashsize"; 1559 TUNABLE_INT_FETCH(tcbhash_tuneable, &hashsize); 1560 if (hashsize == 0) { 1561 /* 1562 * Auto tune the hash size based on maxsockets. 1563 * A perfect hash would have a 1:1 mapping 1564 * (hashsize = maxsockets) however it's been 1565 * suggested that O(2) average is better. 1566 */ 1567 hashsize = maketcp_hashsize(maxsockets / 4); 1568 /* 1569 * Our historical default is 512, 1570 * do not autotune lower than this. 1571 */ 1572 if (hashsize < 512) 1573 hashsize = 512; 1574 if (bootverbose) 1575 printf("%s: %s auto tuned to %d\n", __func__, 1576 tcbhash_tuneable, hashsize); 1577 } 1578 /* 1579 * We require a hashsize to be a power of two. 1580 * Previously if it was not a power of two we would just reset it 1581 * back to 512, which could be a nasty surprise if you did not notice 1582 * the error message. 1583 * Instead what we do is clip it to the closest power of two lower 1584 * than the specified hash value. 1585 */ 1586 if (!powerof2(hashsize)) { 1587 int oldhashsize = hashsize; 1588 1589 hashsize = maketcp_hashsize(hashsize); 1590 /* prevent absurdly low value */ 1591 if (hashsize < 16) 1592 hashsize = 16; 1593 printf("%s: WARNING: TCB hash size not a power of 2, " 1594 "clipped from %d to %d.\n", __func__, oldhashsize, 1595 hashsize); 1596 } 1597 tcp_tcbhashsize = hashsize; 1598 1599 #ifdef INET 1600 IPPROTO_REGISTER(IPPROTO_TCP, tcp_input, tcp_ctlinput); 1601 #endif 1602 #ifdef INET6 1603 IP6PROTO_REGISTER(IPPROTO_TCP, tcp6_input, tcp6_ctlinput); 1604 #endif 1605 } 1606 SYSINIT(tcp_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, tcp_init, NULL); 1607 1608 #ifdef VIMAGE 1609 static void 1610 tcp_destroy(void *unused __unused) 1611 { 1612 int n; 1613 #ifdef TCP_HHOOK 1614 int error; 1615 #endif 1616 1617 /* 1618 * All our processes are gone, all our sockets should be cleaned 1619 * up, which means, we should be past the tcp_discardcb() calls. 1620 * Sleep to let all tcpcb timers really disappear and cleanup. 1621 */ 1622 for (;;) { 1623 INP_INFO_WLOCK(&V_tcbinfo); 1624 n = V_tcbinfo.ipi_count; 1625 INP_INFO_WUNLOCK(&V_tcbinfo); 1626 if (n == 0) 1627 break; 1628 pause("tcpdes", hz / 10); 1629 } 1630 tcp_hc_destroy(); 1631 syncache_destroy(); 1632 in_pcbinfo_destroy(&V_tcbinfo); 1633 /* tcp_discardcb() clears the sack_holes up. */ 1634 uma_zdestroy(V_sack_hole_zone); 1635 1636 /* 1637 * Cannot free the zone until all tcpcbs are released as we attach 1638 * the allocations to them. 1639 */ 1640 tcp_fastopen_destroy(); 1641 1642 COUNTER_ARRAY_FREE(V_tcps_states, TCP_NSTATES); 1643 VNET_PCPUSTAT_FREE(tcpstat); 1644 1645 #ifdef TCP_HHOOK 1646 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_IN]); 1647 if (error != 0) { 1648 printf("%s: WARNING: unable to deregister helper hook " 1649 "type=%d, id=%d: error %d returned\n", __func__, 1650 HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN, error); 1651 } 1652 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_OUT]); 1653 if (error != 0) { 1654 printf("%s: WARNING: unable to deregister helper hook " 1655 "type=%d, id=%d: error %d returned\n", __func__, 1656 HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT, error); 1657 } 1658 #endif 1659 } 1660 VNET_SYSUNINIT(tcp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, tcp_destroy, NULL); 1661 #endif 1662 1663 void 1664 tcp_fini(void *xtp) 1665 { 1666 1667 } 1668 1669 /* 1670 * Fill in the IP and TCP headers for an outgoing packet, given the tcpcb. 1671 * tcp_template used to store this data in mbufs, but we now recopy it out 1672 * of the tcpcb each time to conserve mbufs. 1673 */ 1674 void 1675 tcpip_fillheaders(struct inpcb *inp, uint16_t port, void *ip_ptr, void *tcp_ptr) 1676 { 1677 struct tcphdr *th = (struct tcphdr *)tcp_ptr; 1678 1679 INP_WLOCK_ASSERT(inp); 1680 1681 #ifdef INET6 1682 if ((inp->inp_vflag & INP_IPV6) != 0) { 1683 struct ip6_hdr *ip6; 1684 1685 ip6 = (struct ip6_hdr *)ip_ptr; 1686 ip6->ip6_flow = (ip6->ip6_flow & ~IPV6_FLOWINFO_MASK) | 1687 (inp->inp_flow & IPV6_FLOWINFO_MASK); 1688 ip6->ip6_vfc = (ip6->ip6_vfc & ~IPV6_VERSION_MASK) | 1689 (IPV6_VERSION & IPV6_VERSION_MASK); 1690 if (port == 0) 1691 ip6->ip6_nxt = IPPROTO_TCP; 1692 else 1693 ip6->ip6_nxt = IPPROTO_UDP; 1694 ip6->ip6_plen = htons(sizeof(struct tcphdr)); 1695 ip6->ip6_src = inp->in6p_laddr; 1696 ip6->ip6_dst = inp->in6p_faddr; 1697 } 1698 #endif /* INET6 */ 1699 #if defined(INET6) && defined(INET) 1700 else 1701 #endif 1702 #ifdef INET 1703 { 1704 struct ip *ip; 1705 1706 ip = (struct ip *)ip_ptr; 1707 ip->ip_v = IPVERSION; 1708 ip->ip_hl = 5; 1709 ip->ip_tos = inp->inp_ip_tos; 1710 ip->ip_len = 0; 1711 ip->ip_id = 0; 1712 ip->ip_off = 0; 1713 ip->ip_ttl = inp->inp_ip_ttl; 1714 ip->ip_sum = 0; 1715 if (port == 0) 1716 ip->ip_p = IPPROTO_TCP; 1717 else 1718 ip->ip_p = IPPROTO_UDP; 1719 ip->ip_src = inp->inp_laddr; 1720 ip->ip_dst = inp->inp_faddr; 1721 } 1722 #endif /* INET */ 1723 th->th_sport = inp->inp_lport; 1724 th->th_dport = inp->inp_fport; 1725 th->th_seq = 0; 1726 th->th_ack = 0; 1727 th->th_off = 5; 1728 tcp_set_flags(th, 0); 1729 th->th_win = 0; 1730 th->th_urp = 0; 1731 th->th_sum = 0; /* in_pseudo() is called later for ipv4 */ 1732 } 1733 1734 /* 1735 * Create template to be used to send tcp packets on a connection. 1736 * Allocates an mbuf and fills in a skeletal tcp/ip header. The only 1737 * use for this function is in keepalives, which use tcp_respond. 1738 */ 1739 struct tcptemp * 1740 tcpip_maketemplate(struct inpcb *inp) 1741 { 1742 struct tcptemp *t; 1743 1744 t = malloc(sizeof(*t), M_TEMP, M_NOWAIT); 1745 if (t == NULL) 1746 return (NULL); 1747 tcpip_fillheaders(inp, 0, (void *)&t->tt_ipgen, (void *)&t->tt_t); 1748 return (t); 1749 } 1750 1751 /* 1752 * Send a single message to the TCP at address specified by 1753 * the given TCP/IP header. If m == NULL, then we make a copy 1754 * of the tcpiphdr at th and send directly to the addressed host. 1755 * This is used to force keep alive messages out using the TCP 1756 * template for a connection. If flags are given then we send 1757 * a message back to the TCP which originated the segment th, 1758 * and discard the mbuf containing it and any other attached mbufs. 1759 * 1760 * In any case the ack and sequence number of the transmitted 1761 * segment are as specified by the parameters. 1762 * 1763 * NOTE: If m != NULL, then th must point to *inside* the mbuf. 1764 */ 1765 void 1766 tcp_respond(struct tcpcb *tp, void *ipgen, struct tcphdr *th, struct mbuf *m, 1767 tcp_seq ack, tcp_seq seq, uint16_t flags) 1768 { 1769 struct tcpopt to; 1770 struct inpcb *inp; 1771 struct ip *ip; 1772 struct mbuf *optm; 1773 struct udphdr *uh = NULL; 1774 struct tcphdr *nth; 1775 struct tcp_log_buffer *lgb; 1776 u_char *optp; 1777 #ifdef INET6 1778 struct ip6_hdr *ip6; 1779 int isipv6; 1780 #endif /* INET6 */ 1781 int optlen, tlen, win, ulen; 1782 int ect = 0; 1783 bool incl_opts; 1784 uint16_t port; 1785 int output_ret; 1786 #ifdef INVARIANTS 1787 int thflags = tcp_get_flags(th); 1788 #endif 1789 1790 KASSERT(tp != NULL || m != NULL, ("tcp_respond: tp and m both NULL")); 1791 NET_EPOCH_ASSERT(); 1792 1793 #ifdef INET6 1794 isipv6 = ((struct ip *)ipgen)->ip_v == (IPV6_VERSION >> 4); 1795 ip6 = ipgen; 1796 #endif /* INET6 */ 1797 ip = ipgen; 1798 1799 if (tp != NULL) { 1800 inp = tptoinpcb(tp); 1801 INP_LOCK_ASSERT(inp); 1802 } else 1803 inp = NULL; 1804 1805 if (m != NULL) { 1806 #ifdef INET6 1807 if (isipv6 && ip6 && (ip6->ip6_nxt == IPPROTO_UDP)) 1808 port = m->m_pkthdr.tcp_tun_port; 1809 else 1810 #endif 1811 if (ip && (ip->ip_p == IPPROTO_UDP)) 1812 port = m->m_pkthdr.tcp_tun_port; 1813 else 1814 port = 0; 1815 } else 1816 port = tp->t_port; 1817 1818 incl_opts = false; 1819 win = 0; 1820 if (tp != NULL) { 1821 if (!(flags & TH_RST)) { 1822 win = sbspace(&inp->inp_socket->so_rcv); 1823 if (win > TCP_MAXWIN << tp->rcv_scale) 1824 win = TCP_MAXWIN << tp->rcv_scale; 1825 } 1826 if ((tp->t_flags & TF_NOOPT) == 0) 1827 incl_opts = true; 1828 } 1829 if (m == NULL) { 1830 m = m_gethdr(M_NOWAIT, MT_DATA); 1831 if (m == NULL) 1832 return; 1833 m->m_data += max_linkhdr; 1834 #ifdef INET6 1835 if (isipv6) { 1836 bcopy((caddr_t)ip6, mtod(m, caddr_t), 1837 sizeof(struct ip6_hdr)); 1838 ip6 = mtod(m, struct ip6_hdr *); 1839 nth = (struct tcphdr *)(ip6 + 1); 1840 if (port) { 1841 /* Insert a UDP header */ 1842 uh = (struct udphdr *)nth; 1843 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1844 uh->uh_dport = port; 1845 nth = (struct tcphdr *)(uh + 1); 1846 } 1847 } else 1848 #endif /* INET6 */ 1849 { 1850 bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip)); 1851 ip = mtod(m, struct ip *); 1852 nth = (struct tcphdr *)(ip + 1); 1853 if (port) { 1854 /* Insert a UDP header */ 1855 uh = (struct udphdr *)nth; 1856 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1857 uh->uh_dport = port; 1858 nth = (struct tcphdr *)(uh + 1); 1859 } 1860 } 1861 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr)); 1862 flags = TH_ACK; 1863 } else if ((!M_WRITABLE(m)) || (port != 0)) { 1864 struct mbuf *n; 1865 1866 /* Can't reuse 'm', allocate a new mbuf. */ 1867 n = m_gethdr(M_NOWAIT, MT_DATA); 1868 if (n == NULL) { 1869 m_freem(m); 1870 return; 1871 } 1872 1873 if (!m_dup_pkthdr(n, m, M_NOWAIT)) { 1874 m_freem(m); 1875 m_freem(n); 1876 return; 1877 } 1878 1879 n->m_data += max_linkhdr; 1880 /* m_len is set later */ 1881 #define xchg(a,b,type) { type t; t=a; a=b; b=t; } 1882 #ifdef INET6 1883 if (isipv6) { 1884 bcopy((caddr_t)ip6, mtod(n, caddr_t), 1885 sizeof(struct ip6_hdr)); 1886 ip6 = mtod(n, struct ip6_hdr *); 1887 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); 1888 nth = (struct tcphdr *)(ip6 + 1); 1889 if (port) { 1890 /* Insert a UDP header */ 1891 uh = (struct udphdr *)nth; 1892 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1893 uh->uh_dport = port; 1894 nth = (struct tcphdr *)(uh + 1); 1895 } 1896 } else 1897 #endif /* INET6 */ 1898 { 1899 bcopy((caddr_t)ip, mtod(n, caddr_t), sizeof(struct ip)); 1900 ip = mtod(n, struct ip *); 1901 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t); 1902 nth = (struct tcphdr *)(ip + 1); 1903 if (port) { 1904 /* Insert a UDP header */ 1905 uh = (struct udphdr *)nth; 1906 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1907 uh->uh_dport = port; 1908 nth = (struct tcphdr *)(uh + 1); 1909 } 1910 } 1911 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr)); 1912 xchg(nth->th_dport, nth->th_sport, uint16_t); 1913 th = nth; 1914 m_freem(m); 1915 m = n; 1916 } else { 1917 /* 1918 * reuse the mbuf. 1919 * XXX MRT We inherit the FIB, which is lucky. 1920 */ 1921 m_freem(m->m_next); 1922 m->m_next = NULL; 1923 m->m_data = (caddr_t)ipgen; 1924 /* m_len is set later */ 1925 #ifdef INET6 1926 if (isipv6) { 1927 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); 1928 nth = (struct tcphdr *)(ip6 + 1); 1929 } else 1930 #endif /* INET6 */ 1931 { 1932 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t); 1933 nth = (struct tcphdr *)(ip + 1); 1934 } 1935 if (th != nth) { 1936 /* 1937 * this is usually a case when an extension header 1938 * exists between the IPv6 header and the 1939 * TCP header. 1940 */ 1941 nth->th_sport = th->th_sport; 1942 nth->th_dport = th->th_dport; 1943 } 1944 xchg(nth->th_dport, nth->th_sport, uint16_t); 1945 #undef xchg 1946 } 1947 tlen = 0; 1948 #ifdef INET6 1949 if (isipv6) 1950 tlen = sizeof (struct ip6_hdr) + sizeof (struct tcphdr); 1951 #endif 1952 #if defined(INET) && defined(INET6) 1953 else 1954 #endif 1955 #ifdef INET 1956 tlen = sizeof (struct tcpiphdr); 1957 #endif 1958 if (port) 1959 tlen += sizeof (struct udphdr); 1960 #ifdef INVARIANTS 1961 m->m_len = 0; 1962 KASSERT(M_TRAILINGSPACE(m) >= tlen, 1963 ("Not enough trailing space for message (m=%p, need=%d, have=%ld)", 1964 m, tlen, (long)M_TRAILINGSPACE(m))); 1965 #endif 1966 m->m_len = tlen; 1967 to.to_flags = 0; 1968 if (incl_opts) { 1969 ect = tcp_ecn_output_established(tp, &flags, 0, false); 1970 /* Make sure we have room. */ 1971 if (M_TRAILINGSPACE(m) < TCP_MAXOLEN) { 1972 m->m_next = m_get(M_NOWAIT, MT_DATA); 1973 if (m->m_next) { 1974 optp = mtod(m->m_next, u_char *); 1975 optm = m->m_next; 1976 } else 1977 incl_opts = false; 1978 } else { 1979 optp = (u_char *) (nth + 1); 1980 optm = m; 1981 } 1982 } 1983 if (incl_opts) { 1984 /* Timestamps. */ 1985 if (tp->t_flags & TF_RCVD_TSTMP) { 1986 to.to_tsval = tcp_ts_getticks() + tp->ts_offset; 1987 to.to_tsecr = tp->ts_recent; 1988 to.to_flags |= TOF_TS; 1989 } 1990 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 1991 /* TCP-MD5 (RFC2385). */ 1992 if (tp->t_flags & TF_SIGNATURE) 1993 to.to_flags |= TOF_SIGNATURE; 1994 #endif 1995 /* Add the options. */ 1996 tlen += optlen = tcp_addoptions(&to, optp); 1997 1998 /* Update m_len in the correct mbuf. */ 1999 optm->m_len += optlen; 2000 } else 2001 optlen = 0; 2002 #ifdef INET6 2003 if (isipv6) { 2004 if (uh) { 2005 ulen = tlen - sizeof(struct ip6_hdr); 2006 uh->uh_ulen = htons(ulen); 2007 } 2008 ip6->ip6_flow = htonl(ect << 20); 2009 ip6->ip6_vfc = IPV6_VERSION; 2010 if (port) 2011 ip6->ip6_nxt = IPPROTO_UDP; 2012 else 2013 ip6->ip6_nxt = IPPROTO_TCP; 2014 ip6->ip6_plen = htons(tlen - sizeof(*ip6)); 2015 } 2016 #endif 2017 #if defined(INET) && defined(INET6) 2018 else 2019 #endif 2020 #ifdef INET 2021 { 2022 if (uh) { 2023 ulen = tlen - sizeof(struct ip); 2024 uh->uh_ulen = htons(ulen); 2025 } 2026 ip->ip_tos = ect; 2027 ip->ip_len = htons(tlen); 2028 ip->ip_ttl = V_ip_defttl; 2029 if (port) { 2030 ip->ip_p = IPPROTO_UDP; 2031 } else { 2032 ip->ip_p = IPPROTO_TCP; 2033 } 2034 if (V_path_mtu_discovery) 2035 ip->ip_off |= htons(IP_DF); 2036 } 2037 #endif 2038 m->m_pkthdr.len = tlen; 2039 m->m_pkthdr.rcvif = NULL; 2040 #ifdef MAC 2041 if (inp != NULL) { 2042 /* 2043 * Packet is associated with a socket, so allow the 2044 * label of the response to reflect the socket label. 2045 */ 2046 INP_LOCK_ASSERT(inp); 2047 mac_inpcb_create_mbuf(inp, m); 2048 } else { 2049 /* 2050 * Packet is not associated with a socket, so possibly 2051 * update the label in place. 2052 */ 2053 mac_netinet_tcp_reply(m); 2054 } 2055 #endif 2056 nth->th_seq = htonl(seq); 2057 nth->th_ack = htonl(ack); 2058 nth->th_off = (sizeof (struct tcphdr) + optlen) >> 2; 2059 tcp_set_flags(nth, flags); 2060 if (tp != NULL) 2061 nth->th_win = htons((u_short) (win >> tp->rcv_scale)); 2062 else 2063 nth->th_win = htons((u_short)win); 2064 nth->th_urp = 0; 2065 2066 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 2067 if (to.to_flags & TOF_SIGNATURE) { 2068 if (!TCPMD5_ENABLED() || 2069 TCPMD5_OUTPUT(m, nth, to.to_signature) != 0) { 2070 m_freem(m); 2071 return; 2072 } 2073 } 2074 #endif 2075 2076 #ifdef INET6 2077 if (isipv6) { 2078 if (port) { 2079 m->m_pkthdr.csum_flags = CSUM_UDP_IPV6; 2080 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 2081 uh->uh_sum = in6_cksum_pseudo(ip6, ulen, IPPROTO_UDP, 0); 2082 nth->th_sum = 0; 2083 } else { 2084 m->m_pkthdr.csum_flags = CSUM_TCP_IPV6; 2085 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); 2086 nth->th_sum = in6_cksum_pseudo(ip6, 2087 tlen - sizeof(struct ip6_hdr), IPPROTO_TCP, 0); 2088 } 2089 ip6->ip6_hlim = in6_selecthlim(inp, NULL); 2090 } 2091 #endif /* INET6 */ 2092 #if defined(INET6) && defined(INET) 2093 else 2094 #endif 2095 #ifdef INET 2096 { 2097 if (port) { 2098 uh->uh_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, 2099 htons(ulen + IPPROTO_UDP)); 2100 m->m_pkthdr.csum_flags = CSUM_UDP; 2101 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 2102 nth->th_sum = 0; 2103 } else { 2104 m->m_pkthdr.csum_flags = CSUM_TCP; 2105 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); 2106 nth->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, 2107 htons((u_short)(tlen - sizeof(struct ip) + ip->ip_p))); 2108 } 2109 } 2110 #endif /* INET */ 2111 TCP_PROBE3(debug__output, tp, th, m); 2112 if (flags & TH_RST) 2113 TCP_PROBE5(accept__refused, NULL, NULL, m, tp, nth); 2114 lgb = NULL; 2115 if ((tp != NULL) && tcp_bblogging_on(tp)) { 2116 if (INP_WLOCKED(inp)) { 2117 union tcp_log_stackspecific log; 2118 struct timeval tv; 2119 2120 memset(&log.u_bbr, 0, sizeof(log.u_bbr)); 2121 log.u_bbr.inhpts = inp->inp_in_hpts; 2122 log.u_bbr.flex8 = 4; 2123 log.u_bbr.pkts_out = tp->t_maxseg; 2124 log.u_bbr.timeStamp = tcp_get_usecs(&tv); 2125 log.u_bbr.delivered = 0; 2126 lgb = tcp_log_event(tp, nth, NULL, NULL, TCP_LOG_OUT, 2127 ERRNO_UNK, 0, &log, false, NULL, NULL, 0, &tv); 2128 } else { 2129 /* 2130 * We can not log the packet, since we only own the 2131 * read lock, but a write lock is needed. The read lock 2132 * is not upgraded to a write lock, since only getting 2133 * the read lock was done intentionally to improve the 2134 * handling of SYN flooding attacks. 2135 * This happens only for pure SYN segments received in 2136 * the initial CLOSED state, or received in a more 2137 * advanced state than listen and the UDP encapsulation 2138 * port is unexpected. 2139 * The incoming SYN segments do not really belong to 2140 * the TCP connection and the handling does not change 2141 * the state of the TCP connection. Therefore, the 2142 * sending of the RST segments is not logged. Please 2143 * note that also the incoming SYN segments are not 2144 * logged. 2145 * 2146 * The following code ensures that the above description 2147 * is and stays correct. 2148 */ 2149 KASSERT((thflags & (TH_ACK|TH_SYN)) == TH_SYN && 2150 (tp->t_state == TCPS_CLOSED || 2151 (tp->t_state > TCPS_LISTEN && tp->t_port != port)), 2152 ("%s: Logging of TCP segment with flags 0x%b and " 2153 "UDP encapsulation port %u skipped in state %s", 2154 __func__, thflags, PRINT_TH_FLAGS, 2155 ntohs(port), tcpstates[tp->t_state])); 2156 } 2157 } 2158 2159 if (flags & TH_ACK) 2160 TCPSTAT_INC(tcps_sndacks); 2161 else if (flags & (TH_SYN|TH_FIN|TH_RST)) 2162 TCPSTAT_INC(tcps_sndctrl); 2163 TCPSTAT_INC(tcps_sndtotal); 2164 2165 #ifdef INET6 2166 if (isipv6) { 2167 TCP_PROBE5(send, NULL, tp, ip6, tp, nth); 2168 output_ret = ip6_output(m, NULL, NULL, 0, NULL, NULL, inp); 2169 } 2170 #endif /* INET6 */ 2171 #if defined(INET) && defined(INET6) 2172 else 2173 #endif 2174 #ifdef INET 2175 { 2176 TCP_PROBE5(send, NULL, tp, ip, tp, nth); 2177 output_ret = ip_output(m, NULL, NULL, 0, NULL, inp); 2178 } 2179 #endif 2180 if (lgb != NULL) 2181 lgb->tlb_errno = output_ret; 2182 } 2183 2184 /* 2185 * Create a new TCP control block, making an empty reassembly queue and hooking 2186 * it to the argument protocol control block. The `inp' parameter must have 2187 * come from the zone allocator set up by tcpcbstor declaration. 2188 */ 2189 struct tcpcb * 2190 tcp_newtcpcb(struct inpcb *inp) 2191 { 2192 struct tcpcb *tp = intotcpcb(inp); 2193 #ifdef INET6 2194 int isipv6 = (inp->inp_vflag & INP_IPV6) != 0; 2195 #endif /* INET6 */ 2196 2197 /* 2198 * Historically allocation was done with M_ZERO. There is a lot of 2199 * code that rely on that. For now take safe approach and zero whole 2200 * tcpcb. This definitely can be optimized. 2201 */ 2202 bzero(&tp->t_start_zero, t_zero_size); 2203 2204 /* Initialise cc_var struct for this tcpcb. */ 2205 tp->t_ccv.type = IPPROTO_TCP; 2206 tp->t_ccv.ccvc.tcp = tp; 2207 rw_rlock(&tcp_function_lock); 2208 tp->t_fb = tcp_func_set_ptr; 2209 refcount_acquire(&tp->t_fb->tfb_refcnt); 2210 rw_runlock(&tcp_function_lock); 2211 /* 2212 * Use the current system default CC algorithm. 2213 */ 2214 cc_attach(tp, CC_DEFAULT_ALGO()); 2215 2216 if (CC_ALGO(tp)->cb_init != NULL) 2217 if (CC_ALGO(tp)->cb_init(&tp->t_ccv, NULL) > 0) { 2218 cc_detach(tp); 2219 if (tp->t_fb->tfb_tcp_fb_fini) 2220 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); 2221 refcount_release(&tp->t_fb->tfb_refcnt); 2222 return (NULL); 2223 } 2224 2225 #ifdef TCP_HHOOK 2226 if (khelp_init_osd(HELPER_CLASS_TCP, &tp->t_osd)) { 2227 if (tp->t_fb->tfb_tcp_fb_fini) 2228 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); 2229 refcount_release(&tp->t_fb->tfb_refcnt); 2230 return (NULL); 2231 } 2232 #endif 2233 2234 TAILQ_INIT(&tp->t_segq); 2235 tp->t_maxseg = 2236 #ifdef INET6 2237 isipv6 ? V_tcp_v6mssdflt : 2238 #endif /* INET6 */ 2239 V_tcp_mssdflt; 2240 2241 callout_init_rw(&tp->t_callout, &inp->inp_lock, CALLOUT_RETURNUNLOCKED); 2242 for (int i = 0; i < TT_N; i++) 2243 tp->t_timers[i] = SBT_MAX; 2244 2245 switch (V_tcp_do_rfc1323) { 2246 case 0: 2247 break; 2248 default: 2249 case 1: 2250 tp->t_flags = (TF_REQ_SCALE|TF_REQ_TSTMP); 2251 break; 2252 case 2: 2253 tp->t_flags = TF_REQ_SCALE; 2254 break; 2255 case 3: 2256 tp->t_flags = TF_REQ_TSTMP; 2257 break; 2258 } 2259 if (V_tcp_do_sack) 2260 tp->t_flags |= TF_SACK_PERMIT; 2261 TAILQ_INIT(&tp->snd_holes); 2262 2263 /* 2264 * Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no 2265 * rtt estimate. Set rttvar so that srtt + 4 * rttvar gives 2266 * reasonable initial retransmit time. 2267 */ 2268 tp->t_srtt = TCPTV_SRTTBASE; 2269 tp->t_rttvar = ((tcp_rexmit_initial - TCPTV_SRTTBASE) << TCP_RTTVAR_SHIFT) / 4; 2270 tp->t_rttmin = tcp_rexmit_min; 2271 tp->t_rxtcur = tcp_rexmit_initial; 2272 tp->snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT; 2273 tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT; 2274 tp->t_rcvtime = ticks; 2275 /* We always start with ticks granularity */ 2276 tp->t_tmr_granularity = TCP_TMR_GRANULARITY_TICKS; 2277 /* 2278 * IPv4 TTL initialization is necessary for an IPv6 socket as well, 2279 * because the socket may be bound to an IPv6 wildcard address, 2280 * which may match an IPv4-mapped IPv6 address. 2281 */ 2282 inp->inp_ip_ttl = V_ip_defttl; 2283 #ifdef TCPHPTS 2284 /* 2285 * If using hpts lets drop a random number in so 2286 * not all new connections fall on the same CPU. 2287 */ 2288 inp->inp_hpts_cpu = hpts_random_cpu(inp); 2289 #endif 2290 #ifdef TCPPCAP 2291 /* 2292 * Init the TCP PCAP queues. 2293 */ 2294 tcp_pcap_tcpcb_init(tp); 2295 #endif 2296 #ifdef TCP_BLACKBOX 2297 /* Initialize the per-TCPCB log data. */ 2298 tcp_log_tcpcbinit(tp); 2299 #endif 2300 tp->t_pacing_rate = -1; 2301 if (tp->t_fb->tfb_tcp_fb_init) { 2302 if ((*tp->t_fb->tfb_tcp_fb_init)(tp, &tp->t_fb_ptr)) { 2303 refcount_release(&tp->t_fb->tfb_refcnt); 2304 return (NULL); 2305 } 2306 } 2307 #ifdef STATS 2308 if (V_tcp_perconn_stats_enable == 1) 2309 tp->t_stats = stats_blob_alloc(V_tcp_perconn_stats_dflt_tpl, 0); 2310 #endif 2311 if (V_tcp_do_lrd) 2312 tp->t_flags |= TF_LRD; 2313 2314 return (tp); 2315 } 2316 2317 /* 2318 * Drop a TCP connection, reporting 2319 * the specified error. If connection is synchronized, 2320 * then send a RST to peer. 2321 */ 2322 struct tcpcb * 2323 tcp_drop(struct tcpcb *tp, int errno) 2324 { 2325 struct socket *so = tptosocket(tp); 2326 2327 NET_EPOCH_ASSERT(); 2328 INP_WLOCK_ASSERT(tptoinpcb(tp)); 2329 2330 if (TCPS_HAVERCVDSYN(tp->t_state)) { 2331 tcp_state_change(tp, TCPS_CLOSED); 2332 /* Don't use tcp_output() here due to possible recursion. */ 2333 (void)tcp_output_nodrop(tp); 2334 TCPSTAT_INC(tcps_drops); 2335 } else 2336 TCPSTAT_INC(tcps_conndrops); 2337 if (errno == ETIMEDOUT && tp->t_softerror) 2338 errno = tp->t_softerror; 2339 so->so_error = errno; 2340 return (tcp_close(tp)); 2341 } 2342 2343 void 2344 tcp_discardcb(struct tcpcb *tp) 2345 { 2346 struct inpcb *inp = tptoinpcb(tp); 2347 struct socket *so = tptosocket(tp); 2348 #ifdef INET6 2349 bool isipv6 = (inp->inp_vflag & INP_IPV6) != 0; 2350 #endif 2351 2352 INP_WLOCK_ASSERT(inp); 2353 2354 tcp_timer_stop(tp); 2355 if (tp->t_fb->tfb_tcp_timer_stop_all) { 2356 tp->t_fb->tfb_tcp_timer_stop_all(tp); 2357 } 2358 2359 /* free the reassembly queue, if any */ 2360 tcp_reass_flush(tp); 2361 2362 #ifdef TCP_OFFLOAD 2363 /* Disconnect offload device, if any. */ 2364 if (tp->t_flags & TF_TOE) 2365 tcp_offload_detach(tp); 2366 #endif 2367 2368 tcp_free_sackholes(tp); 2369 2370 #ifdef TCPPCAP 2371 /* Free the TCP PCAP queues. */ 2372 tcp_pcap_drain(&(tp->t_inpkts)); 2373 tcp_pcap_drain(&(tp->t_outpkts)); 2374 #endif 2375 2376 /* Allow the CC algorithm to clean up after itself. */ 2377 if (CC_ALGO(tp)->cb_destroy != NULL) 2378 CC_ALGO(tp)->cb_destroy(&tp->t_ccv); 2379 CC_DATA(tp) = NULL; 2380 /* Detach from the CC algorithm */ 2381 cc_detach(tp); 2382 2383 #ifdef TCP_HHOOK 2384 khelp_destroy_osd(&tp->t_osd); 2385 #endif 2386 #ifdef STATS 2387 stats_blob_destroy(tp->t_stats); 2388 #endif 2389 2390 CC_ALGO(tp) = NULL; 2391 2392 #ifdef TCP_BLACKBOX 2393 tcp_log_tcpcbfini(tp); 2394 #endif 2395 TCPSTATES_DEC(tp->t_state); 2396 if (tp->t_fb->tfb_tcp_fb_fini) 2397 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); 2398 2399 /* 2400 * If we got enough samples through the srtt filter, 2401 * save the rtt and rttvar in the routing entry. 2402 * 'Enough' is arbitrarily defined as 4 rtt samples. 2403 * 4 samples is enough for the srtt filter to converge 2404 * to within enough % of the correct value; fewer samples 2405 * and we could save a bogus rtt. The danger is not high 2406 * as tcp quickly recovers from everything. 2407 * XXX: Works very well but needs some more statistics! 2408 * 2409 * XXXRRS: Updating must be after the stack fini() since 2410 * that may be converting some internal representation of 2411 * say srtt etc into the general one used by other stacks. 2412 * Lets also at least protect against the so being NULL 2413 * as RW stated below. 2414 */ 2415 if ((tp->t_rttupdated >= 4) && (so != NULL)) { 2416 struct hc_metrics_lite metrics; 2417 uint32_t ssthresh; 2418 2419 bzero(&metrics, sizeof(metrics)); 2420 /* 2421 * Update the ssthresh always when the conditions below 2422 * are satisfied. This gives us better new start value 2423 * for the congestion avoidance for new connections. 2424 * ssthresh is only set if packet loss occurred on a session. 2425 * 2426 * XXXRW: 'so' may be NULL here, and/or socket buffer may be 2427 * being torn down. Ideally this code would not use 'so'. 2428 */ 2429 ssthresh = tp->snd_ssthresh; 2430 if (ssthresh != 0 && ssthresh < so->so_snd.sb_hiwat / 2) { 2431 /* 2432 * convert the limit from user data bytes to 2433 * packets then to packet data bytes. 2434 */ 2435 ssthresh = (ssthresh + tp->t_maxseg / 2) / tp->t_maxseg; 2436 if (ssthresh < 2) 2437 ssthresh = 2; 2438 ssthresh *= (tp->t_maxseg + 2439 #ifdef INET6 2440 (isipv6 ? sizeof (struct ip6_hdr) + 2441 sizeof (struct tcphdr) : 2442 #endif 2443 sizeof (struct tcpiphdr) 2444 #ifdef INET6 2445 ) 2446 #endif 2447 ); 2448 } else 2449 ssthresh = 0; 2450 metrics.rmx_ssthresh = ssthresh; 2451 2452 metrics.rmx_rtt = tp->t_srtt; 2453 metrics.rmx_rttvar = tp->t_rttvar; 2454 metrics.rmx_cwnd = tp->snd_cwnd; 2455 metrics.rmx_sendpipe = 0; 2456 metrics.rmx_recvpipe = 0; 2457 2458 tcp_hc_update(&inp->inp_inc, &metrics); 2459 } 2460 2461 refcount_release(&tp->t_fb->tfb_refcnt); 2462 } 2463 2464 /* 2465 * Attempt to close a TCP control block, marking it as dropped, and freeing 2466 * the socket if we hold the only reference. 2467 */ 2468 struct tcpcb * 2469 tcp_close(struct tcpcb *tp) 2470 { 2471 struct inpcb *inp = tptoinpcb(tp); 2472 struct socket *so = tptosocket(tp); 2473 2474 INP_WLOCK_ASSERT(inp); 2475 2476 #ifdef TCP_OFFLOAD 2477 if (tp->t_state == TCPS_LISTEN) 2478 tcp_offload_listen_stop(tp); 2479 #endif 2480 /* 2481 * This releases the TFO pending counter resource for TFO listen 2482 * sockets as well as passively-created TFO sockets that transition 2483 * from SYN_RECEIVED to CLOSED. 2484 */ 2485 if (tp->t_tfo_pending) { 2486 tcp_fastopen_decrement_counter(tp->t_tfo_pending); 2487 tp->t_tfo_pending = NULL; 2488 } 2489 #ifdef TCPHPTS 2490 tcp_hpts_remove(inp); 2491 #endif 2492 in_pcbdrop(inp); 2493 TCPSTAT_INC(tcps_closed); 2494 if (tp->t_state != TCPS_CLOSED) 2495 tcp_state_change(tp, TCPS_CLOSED); 2496 KASSERT(inp->inp_socket != NULL, ("tcp_close: inp_socket NULL")); 2497 soisdisconnected(so); 2498 if (inp->inp_flags & INP_SOCKREF) { 2499 inp->inp_flags &= ~INP_SOCKREF; 2500 INP_WUNLOCK(inp); 2501 sorele(so); 2502 return (NULL); 2503 } 2504 return (tp); 2505 } 2506 2507 /* 2508 * Notify a tcp user of an asynchronous error; 2509 * store error as soft error, but wake up user 2510 * (for now, won't do anything until can select for soft error). 2511 * 2512 * Do not wake up user since there currently is no mechanism for 2513 * reporting soft errors (yet - a kqueue filter may be added). 2514 */ 2515 static struct inpcb * 2516 tcp_notify(struct inpcb *inp, int error) 2517 { 2518 struct tcpcb *tp; 2519 2520 INP_WLOCK_ASSERT(inp); 2521 2522 tp = intotcpcb(inp); 2523 KASSERT(tp != NULL, ("tcp_notify: tp == NULL")); 2524 2525 /* 2526 * Ignore some errors if we are hooked up. 2527 * If connection hasn't completed, has retransmitted several times, 2528 * and receives a second error, give up now. This is better 2529 * than waiting a long time to establish a connection that 2530 * can never complete. 2531 */ 2532 if (tp->t_state == TCPS_ESTABLISHED && 2533 (error == EHOSTUNREACH || error == ENETUNREACH || 2534 error == EHOSTDOWN)) { 2535 if (inp->inp_route.ro_nh) { 2536 NH_FREE(inp->inp_route.ro_nh); 2537 inp->inp_route.ro_nh = (struct nhop_object *)NULL; 2538 } 2539 return (inp); 2540 } else if (tp->t_state < TCPS_ESTABLISHED && tp->t_rxtshift > 3 && 2541 tp->t_softerror) { 2542 tp = tcp_drop(tp, error); 2543 if (tp != NULL) 2544 return (inp); 2545 else 2546 return (NULL); 2547 } else { 2548 tp->t_softerror = error; 2549 return (inp); 2550 } 2551 #if 0 2552 wakeup( &so->so_timeo); 2553 sorwakeup(so); 2554 sowwakeup(so); 2555 #endif 2556 } 2557 2558 static int 2559 tcp_pcblist(SYSCTL_HANDLER_ARGS) 2560 { 2561 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, 2562 INPLOOKUP_RLOCKPCB); 2563 struct xinpgen xig; 2564 struct inpcb *inp; 2565 int error; 2566 2567 if (req->newptr != NULL) 2568 return (EPERM); 2569 2570 if (req->oldptr == NULL) { 2571 int n; 2572 2573 n = V_tcbinfo.ipi_count + 2574 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); 2575 n += imax(n / 8, 10); 2576 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xtcpcb); 2577 return (0); 2578 } 2579 2580 if ((error = sysctl_wire_old_buffer(req, 0)) != 0) 2581 return (error); 2582 2583 bzero(&xig, sizeof(xig)); 2584 xig.xig_len = sizeof xig; 2585 xig.xig_count = V_tcbinfo.ipi_count + 2586 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); 2587 xig.xig_gen = V_tcbinfo.ipi_gencnt; 2588 xig.xig_sogen = so_gencnt; 2589 error = SYSCTL_OUT(req, &xig, sizeof xig); 2590 if (error) 2591 return (error); 2592 2593 error = syncache_pcblist(req); 2594 if (error) 2595 return (error); 2596 2597 while ((inp = inp_next(&inpi)) != NULL) { 2598 if (inp->inp_gencnt <= xig.xig_gen && 2599 cr_canseeinpcb(req->td->td_ucred, inp) == 0) { 2600 struct xtcpcb xt; 2601 2602 tcp_inptoxtp(inp, &xt); 2603 error = SYSCTL_OUT(req, &xt, sizeof xt); 2604 if (error) { 2605 INP_RUNLOCK(inp); 2606 break; 2607 } else 2608 continue; 2609 } 2610 } 2611 2612 if (!error) { 2613 /* 2614 * Give the user an updated idea of our state. 2615 * If the generation differs from what we told 2616 * her before, she knows that something happened 2617 * while we were processing this request, and it 2618 * might be necessary to retry. 2619 */ 2620 xig.xig_gen = V_tcbinfo.ipi_gencnt; 2621 xig.xig_sogen = so_gencnt; 2622 xig.xig_count = V_tcbinfo.ipi_count + 2623 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); 2624 error = SYSCTL_OUT(req, &xig, sizeof xig); 2625 } 2626 2627 return (error); 2628 } 2629 2630 SYSCTL_PROC(_net_inet_tcp, TCPCTL_PCBLIST, pcblist, 2631 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_NEEDGIANT, 2632 NULL, 0, tcp_pcblist, "S,xtcpcb", 2633 "List of active TCP connections"); 2634 2635 #ifdef INET 2636 static int 2637 tcp_getcred(SYSCTL_HANDLER_ARGS) 2638 { 2639 struct xucred xuc; 2640 struct sockaddr_in addrs[2]; 2641 struct epoch_tracker et; 2642 struct inpcb *inp; 2643 int error; 2644 2645 error = priv_check(req->td, PRIV_NETINET_GETCRED); 2646 if (error) 2647 return (error); 2648 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 2649 if (error) 2650 return (error); 2651 NET_EPOCH_ENTER(et); 2652 inp = in_pcblookup(&V_tcbinfo, addrs[1].sin_addr, addrs[1].sin_port, 2653 addrs[0].sin_addr, addrs[0].sin_port, INPLOOKUP_RLOCKPCB, NULL); 2654 NET_EPOCH_EXIT(et); 2655 if (inp != NULL) { 2656 if (error == 0) 2657 error = cr_canseeinpcb(req->td->td_ucred, inp); 2658 if (error == 0) 2659 cru2x(inp->inp_cred, &xuc); 2660 INP_RUNLOCK(inp); 2661 } else 2662 error = ENOENT; 2663 if (error == 0) 2664 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 2665 return (error); 2666 } 2667 2668 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, getcred, 2669 CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_NEEDGIANT, 2670 0, 0, tcp_getcred, "S,xucred", 2671 "Get the xucred of a TCP connection"); 2672 #endif /* INET */ 2673 2674 #ifdef INET6 2675 static int 2676 tcp6_getcred(SYSCTL_HANDLER_ARGS) 2677 { 2678 struct epoch_tracker et; 2679 struct xucred xuc; 2680 struct sockaddr_in6 addrs[2]; 2681 struct inpcb *inp; 2682 int error; 2683 #ifdef INET 2684 int mapped = 0; 2685 #endif 2686 2687 error = priv_check(req->td, PRIV_NETINET_GETCRED); 2688 if (error) 2689 return (error); 2690 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 2691 if (error) 2692 return (error); 2693 if ((error = sa6_embedscope(&addrs[0], V_ip6_use_defzone)) != 0 || 2694 (error = sa6_embedscope(&addrs[1], V_ip6_use_defzone)) != 0) { 2695 return (error); 2696 } 2697 if (IN6_IS_ADDR_V4MAPPED(&addrs[0].sin6_addr)) { 2698 #ifdef INET 2699 if (IN6_IS_ADDR_V4MAPPED(&addrs[1].sin6_addr)) 2700 mapped = 1; 2701 else 2702 #endif 2703 return (EINVAL); 2704 } 2705 2706 NET_EPOCH_ENTER(et); 2707 #ifdef INET 2708 if (mapped == 1) 2709 inp = in_pcblookup(&V_tcbinfo, 2710 *(struct in_addr *)&addrs[1].sin6_addr.s6_addr[12], 2711 addrs[1].sin6_port, 2712 *(struct in_addr *)&addrs[0].sin6_addr.s6_addr[12], 2713 addrs[0].sin6_port, INPLOOKUP_RLOCKPCB, NULL); 2714 else 2715 #endif 2716 inp = in6_pcblookup(&V_tcbinfo, 2717 &addrs[1].sin6_addr, addrs[1].sin6_port, 2718 &addrs[0].sin6_addr, addrs[0].sin6_port, 2719 INPLOOKUP_RLOCKPCB, NULL); 2720 NET_EPOCH_EXIT(et); 2721 if (inp != NULL) { 2722 if (error == 0) 2723 error = cr_canseeinpcb(req->td->td_ucred, inp); 2724 if (error == 0) 2725 cru2x(inp->inp_cred, &xuc); 2726 INP_RUNLOCK(inp); 2727 } else 2728 error = ENOENT; 2729 if (error == 0) 2730 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 2731 return (error); 2732 } 2733 2734 SYSCTL_PROC(_net_inet6_tcp6, OID_AUTO, getcred, 2735 CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_NEEDGIANT, 2736 0, 0, tcp6_getcred, "S,xucred", 2737 "Get the xucred of a TCP6 connection"); 2738 #endif /* INET6 */ 2739 2740 #ifdef INET 2741 /* Path MTU to try next when a fragmentation-needed message is received. */ 2742 static inline int 2743 tcp_next_pmtu(const struct icmp *icp, const struct ip *ip) 2744 { 2745 int mtu = ntohs(icp->icmp_nextmtu); 2746 2747 /* If no alternative MTU was proposed, try the next smaller one. */ 2748 if (!mtu) 2749 mtu = ip_next_mtu(ntohs(ip->ip_len), 1); 2750 if (mtu < V_tcp_minmss + sizeof(struct tcpiphdr)) 2751 mtu = V_tcp_minmss + sizeof(struct tcpiphdr); 2752 2753 return (mtu); 2754 } 2755 2756 static void 2757 tcp_ctlinput_with_port(struct icmp *icp, uint16_t port) 2758 { 2759 struct ip *ip; 2760 struct tcphdr *th; 2761 struct inpcb *inp; 2762 struct tcpcb *tp; 2763 struct inpcb *(*notify)(struct inpcb *, int); 2764 struct in_conninfo inc; 2765 tcp_seq icmp_tcp_seq; 2766 int errno, mtu; 2767 2768 errno = icmp_errmap(icp); 2769 switch (errno) { 2770 case 0: 2771 return; 2772 case EMSGSIZE: 2773 notify = tcp_mtudisc_notify; 2774 break; 2775 case ECONNREFUSED: 2776 if (V_icmp_may_rst) 2777 notify = tcp_drop_syn_sent; 2778 else 2779 notify = tcp_notify; 2780 break; 2781 case EHOSTUNREACH: 2782 if (V_icmp_may_rst && icp->icmp_type == ICMP_TIMXCEED) 2783 notify = tcp_drop_syn_sent; 2784 else 2785 notify = tcp_notify; 2786 break; 2787 default: 2788 notify = tcp_notify; 2789 } 2790 2791 ip = &icp->icmp_ip; 2792 th = (struct tcphdr *)((caddr_t)ip + (ip->ip_hl << 2)); 2793 icmp_tcp_seq = th->th_seq; 2794 inp = in_pcblookup(&V_tcbinfo, ip->ip_dst, th->th_dport, ip->ip_src, 2795 th->th_sport, INPLOOKUP_WLOCKPCB, NULL); 2796 if (inp != NULL) { 2797 tp = intotcpcb(inp); 2798 #ifdef TCP_OFFLOAD 2799 if (tp->t_flags & TF_TOE && errno == EMSGSIZE) { 2800 /* 2801 * MTU discovery for offloaded connections. Let 2802 * the TOE driver verify seq# and process it. 2803 */ 2804 mtu = tcp_next_pmtu(icp, ip); 2805 tcp_offload_pmtu_update(tp, icmp_tcp_seq, mtu); 2806 goto out; 2807 } 2808 #endif 2809 if (tp->t_port != port) 2810 goto out; 2811 if (SEQ_GEQ(ntohl(icmp_tcp_seq), tp->snd_una) && 2812 SEQ_LT(ntohl(icmp_tcp_seq), tp->snd_max)) { 2813 if (errno == EMSGSIZE) { 2814 /* 2815 * MTU discovery: we got a needfrag and 2816 * will potentially try a lower MTU. 2817 */ 2818 mtu = tcp_next_pmtu(icp, ip); 2819 2820 /* 2821 * Only process the offered MTU if it 2822 * is smaller than the current one. 2823 */ 2824 if (mtu < tp->t_maxseg + 2825 sizeof(struct tcpiphdr)) { 2826 bzero(&inc, sizeof(inc)); 2827 inc.inc_faddr = ip->ip_dst; 2828 inc.inc_fibnum = 2829 inp->inp_inc.inc_fibnum; 2830 tcp_hc_updatemtu(&inc, mtu); 2831 inp = tcp_mtudisc(inp, mtu); 2832 } 2833 } else 2834 inp = (*notify)(inp, errno); 2835 } 2836 } else { 2837 bzero(&inc, sizeof(inc)); 2838 inc.inc_fport = th->th_dport; 2839 inc.inc_lport = th->th_sport; 2840 inc.inc_faddr = ip->ip_dst; 2841 inc.inc_laddr = ip->ip_src; 2842 syncache_unreach(&inc, icmp_tcp_seq, port); 2843 } 2844 out: 2845 if (inp != NULL) 2846 INP_WUNLOCK(inp); 2847 } 2848 2849 static void 2850 tcp_ctlinput(struct icmp *icmp) 2851 { 2852 tcp_ctlinput_with_port(icmp, htons(0)); 2853 } 2854 2855 static void 2856 tcp_ctlinput_viaudp(udp_tun_icmp_param_t param) 2857 { 2858 /* Its a tunneled TCP over UDP icmp */ 2859 struct icmp *icmp = param.icmp; 2860 struct ip *outer_ip, *inner_ip; 2861 struct udphdr *udp; 2862 struct tcphdr *th, ttemp; 2863 int i_hlen, o_len; 2864 uint16_t port; 2865 2866 outer_ip = (struct ip *)((caddr_t)icmp - sizeof(struct ip)); 2867 inner_ip = &icmp->icmp_ip; 2868 i_hlen = inner_ip->ip_hl << 2; 2869 o_len = ntohs(outer_ip->ip_len); 2870 if (o_len < 2871 (sizeof(struct ip) + 8 + i_hlen + sizeof(struct udphdr) + offsetof(struct tcphdr, th_ack))) { 2872 /* Not enough data present */ 2873 return; 2874 } 2875 /* Ok lets strip out the inner udphdr header by copying up on top of it the tcp hdr */ 2876 udp = (struct udphdr *)(((caddr_t)inner_ip) + i_hlen); 2877 if (ntohs(udp->uh_sport) != V_tcp_udp_tunneling_port) { 2878 return; 2879 } 2880 port = udp->uh_dport; 2881 th = (struct tcphdr *)(udp + 1); 2882 memcpy(&ttemp, th, sizeof(struct tcphdr)); 2883 memcpy(udp, &ttemp, sizeof(struct tcphdr)); 2884 /* Now adjust down the size of the outer IP header */ 2885 o_len -= sizeof(struct udphdr); 2886 outer_ip->ip_len = htons(o_len); 2887 /* Now call in to the normal handling code */ 2888 tcp_ctlinput_with_port(icmp, port); 2889 } 2890 #endif /* INET */ 2891 2892 #ifdef INET6 2893 static inline int 2894 tcp6_next_pmtu(const struct icmp6_hdr *icmp6) 2895 { 2896 int mtu = ntohl(icmp6->icmp6_mtu); 2897 2898 /* 2899 * If no alternative MTU was proposed, or the proposed MTU was too 2900 * small, set to the min. 2901 */ 2902 if (mtu < IPV6_MMTU) 2903 mtu = IPV6_MMTU - 8; /* XXXNP: what is the adjustment for? */ 2904 return (mtu); 2905 } 2906 2907 static void 2908 tcp6_ctlinput_with_port(struct ip6ctlparam *ip6cp, uint16_t port) 2909 { 2910 struct in6_addr *dst; 2911 struct inpcb *(*notify)(struct inpcb *, int); 2912 struct ip6_hdr *ip6; 2913 struct mbuf *m; 2914 struct inpcb *inp; 2915 struct tcpcb *tp; 2916 struct icmp6_hdr *icmp6; 2917 struct in_conninfo inc; 2918 struct tcp_ports { 2919 uint16_t th_sport; 2920 uint16_t th_dport; 2921 } t_ports; 2922 tcp_seq icmp_tcp_seq; 2923 unsigned int mtu; 2924 unsigned int off; 2925 int errno; 2926 2927 icmp6 = ip6cp->ip6c_icmp6; 2928 m = ip6cp->ip6c_m; 2929 ip6 = ip6cp->ip6c_ip6; 2930 off = ip6cp->ip6c_off; 2931 dst = &ip6cp->ip6c_finaldst->sin6_addr; 2932 2933 errno = icmp6_errmap(icmp6); 2934 switch (errno) { 2935 case 0: 2936 return; 2937 case EMSGSIZE: 2938 notify = tcp_mtudisc_notify; 2939 break; 2940 case ECONNREFUSED: 2941 if (V_icmp_may_rst) 2942 notify = tcp_drop_syn_sent; 2943 else 2944 notify = tcp_notify; 2945 break; 2946 case EHOSTUNREACH: 2947 /* 2948 * There are only four ICMPs that may reset connection: 2949 * - administratively prohibited 2950 * - port unreachable 2951 * - time exceeded in transit 2952 * - unknown next header 2953 */ 2954 if (V_icmp_may_rst && 2955 ((icmp6->icmp6_type == ICMP6_DST_UNREACH && 2956 (icmp6->icmp6_code == ICMP6_DST_UNREACH_ADMIN || 2957 icmp6->icmp6_code == ICMP6_DST_UNREACH_NOPORT)) || 2958 (icmp6->icmp6_type == ICMP6_TIME_EXCEEDED && 2959 icmp6->icmp6_code == ICMP6_TIME_EXCEED_TRANSIT) || 2960 (icmp6->icmp6_type == ICMP6_PARAM_PROB && 2961 icmp6->icmp6_code == ICMP6_PARAMPROB_NEXTHEADER))) 2962 notify = tcp_drop_syn_sent; 2963 else 2964 notify = tcp_notify; 2965 break; 2966 default: 2967 notify = tcp_notify; 2968 } 2969 2970 /* Check if we can safely get the ports from the tcp hdr */ 2971 if (m == NULL || 2972 (m->m_pkthdr.len < 2973 (int32_t) (off + sizeof(struct tcp_ports)))) { 2974 return; 2975 } 2976 bzero(&t_ports, sizeof(struct tcp_ports)); 2977 m_copydata(m, off, sizeof(struct tcp_ports), (caddr_t)&t_ports); 2978 inp = in6_pcblookup(&V_tcbinfo, &ip6->ip6_dst, t_ports.th_dport, 2979 &ip6->ip6_src, t_ports.th_sport, INPLOOKUP_WLOCKPCB, NULL); 2980 off += sizeof(struct tcp_ports); 2981 if (m->m_pkthdr.len < (int32_t) (off + sizeof(tcp_seq))) { 2982 goto out; 2983 } 2984 m_copydata(m, off, sizeof(tcp_seq), (caddr_t)&icmp_tcp_seq); 2985 if (inp != NULL) { 2986 tp = intotcpcb(inp); 2987 #ifdef TCP_OFFLOAD 2988 if (tp->t_flags & TF_TOE && errno == EMSGSIZE) { 2989 /* MTU discovery for offloaded connections. */ 2990 mtu = tcp6_next_pmtu(icmp6); 2991 tcp_offload_pmtu_update(tp, icmp_tcp_seq, mtu); 2992 goto out; 2993 } 2994 #endif 2995 if (tp->t_port != port) 2996 goto out; 2997 if (SEQ_GEQ(ntohl(icmp_tcp_seq), tp->snd_una) && 2998 SEQ_LT(ntohl(icmp_tcp_seq), tp->snd_max)) { 2999 if (errno == EMSGSIZE) { 3000 /* 3001 * MTU discovery: 3002 * If we got a needfrag set the MTU 3003 * in the route to the suggested new 3004 * value (if given) and then notify. 3005 */ 3006 mtu = tcp6_next_pmtu(icmp6); 3007 3008 bzero(&inc, sizeof(inc)); 3009 inc.inc_fibnum = M_GETFIB(m); 3010 inc.inc_flags |= INC_ISIPV6; 3011 inc.inc6_faddr = *dst; 3012 if (in6_setscope(&inc.inc6_faddr, 3013 m->m_pkthdr.rcvif, NULL)) 3014 goto out; 3015 /* 3016 * Only process the offered MTU if it 3017 * is smaller than the current one. 3018 */ 3019 if (mtu < tp->t_maxseg + 3020 sizeof (struct tcphdr) + 3021 sizeof (struct ip6_hdr)) { 3022 tcp_hc_updatemtu(&inc, mtu); 3023 tcp_mtudisc(inp, mtu); 3024 ICMP6STAT_INC(icp6s_pmtuchg); 3025 } 3026 } else 3027 inp = (*notify)(inp, errno); 3028 } 3029 } else { 3030 bzero(&inc, sizeof(inc)); 3031 inc.inc_fibnum = M_GETFIB(m); 3032 inc.inc_flags |= INC_ISIPV6; 3033 inc.inc_fport = t_ports.th_dport; 3034 inc.inc_lport = t_ports.th_sport; 3035 inc.inc6_faddr = *dst; 3036 inc.inc6_laddr = ip6->ip6_src; 3037 syncache_unreach(&inc, icmp_tcp_seq, port); 3038 } 3039 out: 3040 if (inp != NULL) 3041 INP_WUNLOCK(inp); 3042 } 3043 3044 static void 3045 tcp6_ctlinput(struct ip6ctlparam *ctl) 3046 { 3047 tcp6_ctlinput_with_port(ctl, htons(0)); 3048 } 3049 3050 static void 3051 tcp6_ctlinput_viaudp(udp_tun_icmp_param_t param) 3052 { 3053 struct ip6ctlparam *ip6cp = param.ip6cp; 3054 struct mbuf *m; 3055 struct udphdr *udp; 3056 uint16_t port; 3057 3058 m = m_pulldown(ip6cp->ip6c_m, ip6cp->ip6c_off, sizeof(struct udphdr), NULL); 3059 if (m == NULL) { 3060 return; 3061 } 3062 udp = mtod(m, struct udphdr *); 3063 if (ntohs(udp->uh_sport) != V_tcp_udp_tunneling_port) { 3064 return; 3065 } 3066 port = udp->uh_dport; 3067 m_adj(m, sizeof(struct udphdr)); 3068 if ((m->m_flags & M_PKTHDR) == 0) { 3069 ip6cp->ip6c_m->m_pkthdr.len -= sizeof(struct udphdr); 3070 } 3071 /* Now call in to the normal handling code */ 3072 tcp6_ctlinput_with_port(ip6cp, port); 3073 } 3074 3075 #endif /* INET6 */ 3076 3077 static uint32_t 3078 tcp_keyed_hash(struct in_conninfo *inc, u_char *key, u_int len) 3079 { 3080 SIPHASH_CTX ctx; 3081 uint32_t hash[2]; 3082 3083 KASSERT(len >= SIPHASH_KEY_LENGTH, 3084 ("%s: keylen %u too short ", __func__, len)); 3085 SipHash24_Init(&ctx); 3086 SipHash_SetKey(&ctx, (uint8_t *)key); 3087 SipHash_Update(&ctx, &inc->inc_fport, sizeof(uint16_t)); 3088 SipHash_Update(&ctx, &inc->inc_lport, sizeof(uint16_t)); 3089 switch (inc->inc_flags & INC_ISIPV6) { 3090 #ifdef INET 3091 case 0: 3092 SipHash_Update(&ctx, &inc->inc_faddr, sizeof(struct in_addr)); 3093 SipHash_Update(&ctx, &inc->inc_laddr, sizeof(struct in_addr)); 3094 break; 3095 #endif 3096 #ifdef INET6 3097 case INC_ISIPV6: 3098 SipHash_Update(&ctx, &inc->inc6_faddr, sizeof(struct in6_addr)); 3099 SipHash_Update(&ctx, &inc->inc6_laddr, sizeof(struct in6_addr)); 3100 break; 3101 #endif 3102 } 3103 SipHash_Final((uint8_t *)hash, &ctx); 3104 3105 return (hash[0] ^ hash[1]); 3106 } 3107 3108 uint32_t 3109 tcp_new_ts_offset(struct in_conninfo *inc) 3110 { 3111 struct in_conninfo inc_store, *local_inc; 3112 3113 if (!V_tcp_ts_offset_per_conn) { 3114 memcpy(&inc_store, inc, sizeof(struct in_conninfo)); 3115 inc_store.inc_lport = 0; 3116 inc_store.inc_fport = 0; 3117 local_inc = &inc_store; 3118 } else { 3119 local_inc = inc; 3120 } 3121 return (tcp_keyed_hash(local_inc, V_ts_offset_secret, 3122 sizeof(V_ts_offset_secret))); 3123 } 3124 3125 /* 3126 * Following is where TCP initial sequence number generation occurs. 3127 * 3128 * There are two places where we must use initial sequence numbers: 3129 * 1. In SYN-ACK packets. 3130 * 2. In SYN packets. 3131 * 3132 * All ISNs for SYN-ACK packets are generated by the syncache. See 3133 * tcp_syncache.c for details. 3134 * 3135 * The ISNs in SYN packets must be monotonic; TIME_WAIT recycling 3136 * depends on this property. In addition, these ISNs should be 3137 * unguessable so as to prevent connection hijacking. To satisfy 3138 * the requirements of this situation, the algorithm outlined in 3139 * RFC 1948 is used, with only small modifications. 3140 * 3141 * Implementation details: 3142 * 3143 * Time is based off the system timer, and is corrected so that it 3144 * increases by one megabyte per second. This allows for proper 3145 * recycling on high speed LANs while still leaving over an hour 3146 * before rollover. 3147 * 3148 * As reading the *exact* system time is too expensive to be done 3149 * whenever setting up a TCP connection, we increment the time 3150 * offset in two ways. First, a small random positive increment 3151 * is added to isn_offset for each connection that is set up. 3152 * Second, the function tcp_isn_tick fires once per clock tick 3153 * and increments isn_offset as necessary so that sequence numbers 3154 * are incremented at approximately ISN_BYTES_PER_SECOND. The 3155 * random positive increments serve only to ensure that the same 3156 * exact sequence number is never sent out twice (as could otherwise 3157 * happen when a port is recycled in less than the system tick 3158 * interval.) 3159 * 3160 * net.inet.tcp.isn_reseed_interval controls the number of seconds 3161 * between seeding of isn_secret. This is normally set to zero, 3162 * as reseeding should not be necessary. 3163 * 3164 * Locking of the global variables isn_secret, isn_last_reseed, isn_offset, 3165 * isn_offset_old, and isn_ctx is performed using the ISN lock. In 3166 * general, this means holding an exclusive (write) lock. 3167 */ 3168 3169 #define ISN_BYTES_PER_SECOND 1048576 3170 #define ISN_STATIC_INCREMENT 4096 3171 #define ISN_RANDOM_INCREMENT (4096 - 1) 3172 #define ISN_SECRET_LENGTH SIPHASH_KEY_LENGTH 3173 3174 VNET_DEFINE_STATIC(u_char, isn_secret[ISN_SECRET_LENGTH]); 3175 VNET_DEFINE_STATIC(int, isn_last); 3176 VNET_DEFINE_STATIC(int, isn_last_reseed); 3177 VNET_DEFINE_STATIC(u_int32_t, isn_offset); 3178 VNET_DEFINE_STATIC(u_int32_t, isn_offset_old); 3179 3180 #define V_isn_secret VNET(isn_secret) 3181 #define V_isn_last VNET(isn_last) 3182 #define V_isn_last_reseed VNET(isn_last_reseed) 3183 #define V_isn_offset VNET(isn_offset) 3184 #define V_isn_offset_old VNET(isn_offset_old) 3185 3186 tcp_seq 3187 tcp_new_isn(struct in_conninfo *inc) 3188 { 3189 tcp_seq new_isn; 3190 u_int32_t projected_offset; 3191 3192 ISN_LOCK(); 3193 /* Seed if this is the first use, reseed if requested. */ 3194 if ((V_isn_last_reseed == 0) || ((V_tcp_isn_reseed_interval > 0) && 3195 (((u_int)V_isn_last_reseed + (u_int)V_tcp_isn_reseed_interval*hz) 3196 < (u_int)ticks))) { 3197 arc4rand(&V_isn_secret, sizeof(V_isn_secret), 0); 3198 V_isn_last_reseed = ticks; 3199 } 3200 3201 /* Compute the hash and return the ISN. */ 3202 new_isn = (tcp_seq)tcp_keyed_hash(inc, V_isn_secret, 3203 sizeof(V_isn_secret)); 3204 V_isn_offset += ISN_STATIC_INCREMENT + 3205 (arc4random() & ISN_RANDOM_INCREMENT); 3206 if (ticks != V_isn_last) { 3207 projected_offset = V_isn_offset_old + 3208 ISN_BYTES_PER_SECOND / hz * (ticks - V_isn_last); 3209 if (SEQ_GT(projected_offset, V_isn_offset)) 3210 V_isn_offset = projected_offset; 3211 V_isn_offset_old = V_isn_offset; 3212 V_isn_last = ticks; 3213 } 3214 new_isn += V_isn_offset; 3215 ISN_UNLOCK(); 3216 return (new_isn); 3217 } 3218 3219 /* 3220 * When a specific ICMP unreachable message is received and the 3221 * connection state is SYN-SENT, drop the connection. This behavior 3222 * is controlled by the icmp_may_rst sysctl. 3223 */ 3224 static struct inpcb * 3225 tcp_drop_syn_sent(struct inpcb *inp, int errno) 3226 { 3227 struct tcpcb *tp; 3228 3229 NET_EPOCH_ASSERT(); 3230 INP_WLOCK_ASSERT(inp); 3231 3232 tp = intotcpcb(inp); 3233 if (tp->t_state != TCPS_SYN_SENT) 3234 return (inp); 3235 3236 if (IS_FASTOPEN(tp->t_flags)) 3237 tcp_fastopen_disable_path(tp); 3238 3239 tp = tcp_drop(tp, errno); 3240 if (tp != NULL) 3241 return (inp); 3242 else 3243 return (NULL); 3244 } 3245 3246 /* 3247 * When `need fragmentation' ICMP is received, update our idea of the MSS 3248 * based on the new value. Also nudge TCP to send something, since we 3249 * know the packet we just sent was dropped. 3250 * This duplicates some code in the tcp_mss() function in tcp_input.c. 3251 */ 3252 static struct inpcb * 3253 tcp_mtudisc_notify(struct inpcb *inp, int error) 3254 { 3255 3256 return (tcp_mtudisc(inp, -1)); 3257 } 3258 3259 static struct inpcb * 3260 tcp_mtudisc(struct inpcb *inp, int mtuoffer) 3261 { 3262 struct tcpcb *tp; 3263 struct socket *so; 3264 3265 INP_WLOCK_ASSERT(inp); 3266 3267 tp = intotcpcb(inp); 3268 KASSERT(tp != NULL, ("tcp_mtudisc: tp == NULL")); 3269 3270 tcp_mss_update(tp, -1, mtuoffer, NULL, NULL); 3271 3272 so = inp->inp_socket; 3273 SOCKBUF_LOCK(&so->so_snd); 3274 /* If the mss is larger than the socket buffer, decrease the mss. */ 3275 if (so->so_snd.sb_hiwat < tp->t_maxseg) 3276 tp->t_maxseg = so->so_snd.sb_hiwat; 3277 SOCKBUF_UNLOCK(&so->so_snd); 3278 3279 TCPSTAT_INC(tcps_mturesent); 3280 tp->t_rtttime = 0; 3281 tp->snd_nxt = tp->snd_una; 3282 tcp_free_sackholes(tp); 3283 tp->snd_recover = tp->snd_max; 3284 if (tp->t_flags & TF_SACK_PERMIT) 3285 EXIT_FASTRECOVERY(tp->t_flags); 3286 if (tp->t_fb->tfb_tcp_mtu_chg != NULL) { 3287 /* 3288 * Conceptually the snd_nxt setting 3289 * and freeing sack holes should 3290 * be done by the default stacks 3291 * own tfb_tcp_mtu_chg(). 3292 */ 3293 tp->t_fb->tfb_tcp_mtu_chg(tp); 3294 } 3295 if (tcp_output(tp) < 0) 3296 return (NULL); 3297 else 3298 return (inp); 3299 } 3300 3301 #ifdef INET 3302 /* 3303 * Look-up the routing entry to the peer of this inpcb. If no route 3304 * is found and it cannot be allocated, then return 0. This routine 3305 * is called by TCP routines that access the rmx structure and by 3306 * tcp_mss_update to get the peer/interface MTU. 3307 */ 3308 uint32_t 3309 tcp_maxmtu(struct in_conninfo *inc, struct tcp_ifcap *cap) 3310 { 3311 struct nhop_object *nh; 3312 struct ifnet *ifp; 3313 uint32_t maxmtu = 0; 3314 3315 KASSERT(inc != NULL, ("tcp_maxmtu with NULL in_conninfo pointer")); 3316 3317 if (inc->inc_faddr.s_addr != INADDR_ANY) { 3318 nh = fib4_lookup(inc->inc_fibnum, inc->inc_faddr, 0, NHR_NONE, 0); 3319 if (nh == NULL) 3320 return (0); 3321 3322 ifp = nh->nh_ifp; 3323 maxmtu = nh->nh_mtu; 3324 3325 /* Report additional interface capabilities. */ 3326 if (cap != NULL) { 3327 if (ifp->if_capenable & IFCAP_TSO4 && 3328 ifp->if_hwassist & CSUM_TSO) { 3329 cap->ifcap |= CSUM_TSO; 3330 cap->tsomax = ifp->if_hw_tsomax; 3331 cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount; 3332 cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize; 3333 } 3334 } 3335 } 3336 return (maxmtu); 3337 } 3338 #endif /* INET */ 3339 3340 #ifdef INET6 3341 uint32_t 3342 tcp_maxmtu6(struct in_conninfo *inc, struct tcp_ifcap *cap) 3343 { 3344 struct nhop_object *nh; 3345 struct in6_addr dst6; 3346 uint32_t scopeid; 3347 struct ifnet *ifp; 3348 uint32_t maxmtu = 0; 3349 3350 KASSERT(inc != NULL, ("tcp_maxmtu6 with NULL in_conninfo pointer")); 3351 3352 if (inc->inc_flags & INC_IPV6MINMTU) 3353 return (IPV6_MMTU); 3354 3355 if (!IN6_IS_ADDR_UNSPECIFIED(&inc->inc6_faddr)) { 3356 in6_splitscope(&inc->inc6_faddr, &dst6, &scopeid); 3357 nh = fib6_lookup(inc->inc_fibnum, &dst6, scopeid, NHR_NONE, 0); 3358 if (nh == NULL) 3359 return (0); 3360 3361 ifp = nh->nh_ifp; 3362 maxmtu = nh->nh_mtu; 3363 3364 /* Report additional interface capabilities. */ 3365 if (cap != NULL) { 3366 if (ifp->if_capenable & IFCAP_TSO6 && 3367 ifp->if_hwassist & CSUM_TSO) { 3368 cap->ifcap |= CSUM_TSO; 3369 cap->tsomax = ifp->if_hw_tsomax; 3370 cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount; 3371 cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize; 3372 } 3373 } 3374 } 3375 3376 return (maxmtu); 3377 } 3378 3379 /* 3380 * Handle setsockopt(IPV6_USE_MIN_MTU) by a TCP stack. 3381 * 3382 * XXXGL: we are updating inpcb here with INC_IPV6MINMTU flag. 3383 * The right place to do that is ip6_setpktopt() that has just been 3384 * executed. By the way it just filled ip6po_minmtu for us. 3385 */ 3386 void 3387 tcp6_use_min_mtu(struct tcpcb *tp) 3388 { 3389 struct inpcb *inp = tptoinpcb(tp); 3390 3391 INP_WLOCK_ASSERT(inp); 3392 /* 3393 * In case of the IPV6_USE_MIN_MTU socket 3394 * option, the INC_IPV6MINMTU flag to announce 3395 * a corresponding MSS during the initial 3396 * handshake. If the TCP connection is not in 3397 * the front states, just reduce the MSS being 3398 * used. This avoids the sending of TCP 3399 * segments which will be fragmented at the 3400 * IPv6 layer. 3401 */ 3402 inp->inp_inc.inc_flags |= INC_IPV6MINMTU; 3403 if ((tp->t_state >= TCPS_SYN_SENT) && 3404 (inp->inp_inc.inc_flags & INC_ISIPV6)) { 3405 struct ip6_pktopts *opt; 3406 3407 opt = inp->in6p_outputopts; 3408 if (opt != NULL && opt->ip6po_minmtu == IP6PO_MINMTU_ALL && 3409 tp->t_maxseg > TCP6_MSS) 3410 tp->t_maxseg = TCP6_MSS; 3411 } 3412 } 3413 #endif /* INET6 */ 3414 3415 /* 3416 * Calculate effective SMSS per RFC5681 definition for a given TCP 3417 * connection at its current state, taking into account SACK and etc. 3418 */ 3419 u_int 3420 tcp_maxseg(const struct tcpcb *tp) 3421 { 3422 u_int optlen; 3423 3424 if (tp->t_flags & TF_NOOPT) 3425 return (tp->t_maxseg); 3426 3427 /* 3428 * Here we have a simplified code from tcp_addoptions(), 3429 * without a proper loop, and having most of paddings hardcoded. 3430 * We might make mistakes with padding here in some edge cases, 3431 * but this is harmless, since result of tcp_maxseg() is used 3432 * only in cwnd and ssthresh estimations. 3433 */ 3434 if (TCPS_HAVEESTABLISHED(tp->t_state)) { 3435 if (tp->t_flags & TF_RCVD_TSTMP) 3436 optlen = TCPOLEN_TSTAMP_APPA; 3437 else 3438 optlen = 0; 3439 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3440 if (tp->t_flags & TF_SIGNATURE) 3441 optlen += PADTCPOLEN(TCPOLEN_SIGNATURE); 3442 #endif 3443 if ((tp->t_flags & TF_SACK_PERMIT) && tp->rcv_numsacks > 0) { 3444 optlen += TCPOLEN_SACKHDR; 3445 optlen += tp->rcv_numsacks * TCPOLEN_SACK; 3446 optlen = PADTCPOLEN(optlen); 3447 } 3448 } else { 3449 if (tp->t_flags & TF_REQ_TSTMP) 3450 optlen = TCPOLEN_TSTAMP_APPA; 3451 else 3452 optlen = PADTCPOLEN(TCPOLEN_MAXSEG); 3453 if (tp->t_flags & TF_REQ_SCALE) 3454 optlen += PADTCPOLEN(TCPOLEN_WINDOW); 3455 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3456 if (tp->t_flags & TF_SIGNATURE) 3457 optlen += PADTCPOLEN(TCPOLEN_SIGNATURE); 3458 #endif 3459 if (tp->t_flags & TF_SACK_PERMIT) 3460 optlen += PADTCPOLEN(TCPOLEN_SACK_PERMITTED); 3461 } 3462 #undef PAD 3463 optlen = min(optlen, TCP_MAXOLEN); 3464 return (tp->t_maxseg - optlen); 3465 } 3466 3467 3468 u_int 3469 tcp_fixed_maxseg(const struct tcpcb *tp) 3470 { 3471 int optlen; 3472 3473 if (tp->t_flags & TF_NOOPT) 3474 return (tp->t_maxseg); 3475 3476 /* 3477 * Here we have a simplified code from tcp_addoptions(), 3478 * without a proper loop, and having most of paddings hardcoded. 3479 * We only consider fixed options that we would send every 3480 * time I.e. SACK is not considered. This is important 3481 * for cc modules to figure out what the modulo of the 3482 * cwnd should be. 3483 */ 3484 #define PAD(len) ((((len) / 4) + !!((len) % 4)) * 4) 3485 if (TCPS_HAVEESTABLISHED(tp->t_state)) { 3486 if (tp->t_flags & TF_RCVD_TSTMP) 3487 optlen = TCPOLEN_TSTAMP_APPA; 3488 else 3489 optlen = 0; 3490 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3491 if (tp->t_flags & TF_SIGNATURE) 3492 optlen += PAD(TCPOLEN_SIGNATURE); 3493 #endif 3494 } else { 3495 if (tp->t_flags & TF_REQ_TSTMP) 3496 optlen = TCPOLEN_TSTAMP_APPA; 3497 else 3498 optlen = PAD(TCPOLEN_MAXSEG); 3499 if (tp->t_flags & TF_REQ_SCALE) 3500 optlen += PAD(TCPOLEN_WINDOW); 3501 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3502 if (tp->t_flags & TF_SIGNATURE) 3503 optlen += PAD(TCPOLEN_SIGNATURE); 3504 #endif 3505 if (tp->t_flags & TF_SACK_PERMIT) 3506 optlen += PAD(TCPOLEN_SACK_PERMITTED); 3507 } 3508 #undef PAD 3509 optlen = min(optlen, TCP_MAXOLEN); 3510 return (tp->t_maxseg - optlen); 3511 } 3512 3513 3514 3515 static int 3516 sysctl_drop(SYSCTL_HANDLER_ARGS) 3517 { 3518 /* addrs[0] is a foreign socket, addrs[1] is a local one. */ 3519 struct sockaddr_storage addrs[2]; 3520 struct inpcb *inp; 3521 struct tcpcb *tp; 3522 #ifdef INET 3523 struct sockaddr_in *fin = NULL, *lin = NULL; 3524 #endif 3525 struct epoch_tracker et; 3526 #ifdef INET6 3527 struct sockaddr_in6 *fin6, *lin6; 3528 #endif 3529 int error; 3530 3531 inp = NULL; 3532 #ifdef INET6 3533 fin6 = lin6 = NULL; 3534 #endif 3535 error = 0; 3536 3537 if (req->oldptr != NULL || req->oldlen != 0) 3538 return (EINVAL); 3539 if (req->newptr == NULL) 3540 return (EPERM); 3541 if (req->newlen < sizeof(addrs)) 3542 return (ENOMEM); 3543 error = SYSCTL_IN(req, &addrs, sizeof(addrs)); 3544 if (error) 3545 return (error); 3546 3547 switch (addrs[0].ss_family) { 3548 #ifdef INET6 3549 case AF_INET6: 3550 fin6 = (struct sockaddr_in6 *)&addrs[0]; 3551 lin6 = (struct sockaddr_in6 *)&addrs[1]; 3552 if (fin6->sin6_len != sizeof(struct sockaddr_in6) || 3553 lin6->sin6_len != sizeof(struct sockaddr_in6)) 3554 return (EINVAL); 3555 if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr)) { 3556 if (!IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr)) 3557 return (EINVAL); 3558 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[0]); 3559 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[1]); 3560 #ifdef INET 3561 fin = (struct sockaddr_in *)&addrs[0]; 3562 lin = (struct sockaddr_in *)&addrs[1]; 3563 #endif 3564 break; 3565 } 3566 error = sa6_embedscope(fin6, V_ip6_use_defzone); 3567 if (error) 3568 return (error); 3569 error = sa6_embedscope(lin6, V_ip6_use_defzone); 3570 if (error) 3571 return (error); 3572 break; 3573 #endif 3574 #ifdef INET 3575 case AF_INET: 3576 fin = (struct sockaddr_in *)&addrs[0]; 3577 lin = (struct sockaddr_in *)&addrs[1]; 3578 if (fin->sin_len != sizeof(struct sockaddr_in) || 3579 lin->sin_len != sizeof(struct sockaddr_in)) 3580 return (EINVAL); 3581 break; 3582 #endif 3583 default: 3584 return (EINVAL); 3585 } 3586 NET_EPOCH_ENTER(et); 3587 switch (addrs[0].ss_family) { 3588 #ifdef INET6 3589 case AF_INET6: 3590 inp = in6_pcblookup(&V_tcbinfo, &fin6->sin6_addr, 3591 fin6->sin6_port, &lin6->sin6_addr, lin6->sin6_port, 3592 INPLOOKUP_WLOCKPCB, NULL); 3593 break; 3594 #endif 3595 #ifdef INET 3596 case AF_INET: 3597 inp = in_pcblookup(&V_tcbinfo, fin->sin_addr, fin->sin_port, 3598 lin->sin_addr, lin->sin_port, INPLOOKUP_WLOCKPCB, NULL); 3599 break; 3600 #endif 3601 } 3602 if (inp != NULL) { 3603 if (!SOLISTENING(inp->inp_socket)) { 3604 tp = intotcpcb(inp); 3605 tp = tcp_drop(tp, ECONNABORTED); 3606 if (tp != NULL) 3607 INP_WUNLOCK(inp); 3608 } else 3609 INP_WUNLOCK(inp); 3610 } else 3611 error = ESRCH; 3612 NET_EPOCH_EXIT(et); 3613 return (error); 3614 } 3615 3616 SYSCTL_PROC(_net_inet_tcp, TCPCTL_DROP, drop, 3617 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | 3618 CTLFLAG_NEEDGIANT, NULL, 0, sysctl_drop, "", 3619 "Drop TCP connection"); 3620 3621 static int 3622 tcp_sysctl_setsockopt(SYSCTL_HANDLER_ARGS) 3623 { 3624 return (sysctl_setsockopt(oidp, arg1, arg2, req, &V_tcbinfo, 3625 &tcp_ctloutput_set)); 3626 } 3627 3628 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, setsockopt, 3629 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | 3630 CTLFLAG_MPSAFE, NULL, 0, tcp_sysctl_setsockopt, "", 3631 "Set socket option for TCP endpoint"); 3632 3633 #ifdef KERN_TLS 3634 static int 3635 sysctl_switch_tls(SYSCTL_HANDLER_ARGS) 3636 { 3637 /* addrs[0] is a foreign socket, addrs[1] is a local one. */ 3638 struct sockaddr_storage addrs[2]; 3639 struct inpcb *inp; 3640 #ifdef INET 3641 struct sockaddr_in *fin = NULL, *lin = NULL; 3642 #endif 3643 struct epoch_tracker et; 3644 #ifdef INET6 3645 struct sockaddr_in6 *fin6, *lin6; 3646 #endif 3647 int error; 3648 3649 inp = NULL; 3650 #ifdef INET6 3651 fin6 = lin6 = NULL; 3652 #endif 3653 error = 0; 3654 3655 if (req->oldptr != NULL || req->oldlen != 0) 3656 return (EINVAL); 3657 if (req->newptr == NULL) 3658 return (EPERM); 3659 if (req->newlen < sizeof(addrs)) 3660 return (ENOMEM); 3661 error = SYSCTL_IN(req, &addrs, sizeof(addrs)); 3662 if (error) 3663 return (error); 3664 3665 switch (addrs[0].ss_family) { 3666 #ifdef INET6 3667 case AF_INET6: 3668 fin6 = (struct sockaddr_in6 *)&addrs[0]; 3669 lin6 = (struct sockaddr_in6 *)&addrs[1]; 3670 if (fin6->sin6_len != sizeof(struct sockaddr_in6) || 3671 lin6->sin6_len != sizeof(struct sockaddr_in6)) 3672 return (EINVAL); 3673 if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr)) { 3674 if (!IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr)) 3675 return (EINVAL); 3676 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[0]); 3677 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[1]); 3678 #ifdef INET 3679 fin = (struct sockaddr_in *)&addrs[0]; 3680 lin = (struct sockaddr_in *)&addrs[1]; 3681 #endif 3682 break; 3683 } 3684 error = sa6_embedscope(fin6, V_ip6_use_defzone); 3685 if (error) 3686 return (error); 3687 error = sa6_embedscope(lin6, V_ip6_use_defzone); 3688 if (error) 3689 return (error); 3690 break; 3691 #endif 3692 #ifdef INET 3693 case AF_INET: 3694 fin = (struct sockaddr_in *)&addrs[0]; 3695 lin = (struct sockaddr_in *)&addrs[1]; 3696 if (fin->sin_len != sizeof(struct sockaddr_in) || 3697 lin->sin_len != sizeof(struct sockaddr_in)) 3698 return (EINVAL); 3699 break; 3700 #endif 3701 default: 3702 return (EINVAL); 3703 } 3704 NET_EPOCH_ENTER(et); 3705 switch (addrs[0].ss_family) { 3706 #ifdef INET6 3707 case AF_INET6: 3708 inp = in6_pcblookup(&V_tcbinfo, &fin6->sin6_addr, 3709 fin6->sin6_port, &lin6->sin6_addr, lin6->sin6_port, 3710 INPLOOKUP_WLOCKPCB, NULL); 3711 break; 3712 #endif 3713 #ifdef INET 3714 case AF_INET: 3715 inp = in_pcblookup(&V_tcbinfo, fin->sin_addr, fin->sin_port, 3716 lin->sin_addr, lin->sin_port, INPLOOKUP_WLOCKPCB, NULL); 3717 break; 3718 #endif 3719 } 3720 NET_EPOCH_EXIT(et); 3721 if (inp != NULL) { 3722 struct socket *so; 3723 3724 so = inp->inp_socket; 3725 soref(so); 3726 error = ktls_set_tx_mode(so, 3727 arg2 == 0 ? TCP_TLS_MODE_SW : TCP_TLS_MODE_IFNET); 3728 INP_WUNLOCK(inp); 3729 sorele(so); 3730 } else 3731 error = ESRCH; 3732 return (error); 3733 } 3734 3735 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, switch_to_sw_tls, 3736 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | 3737 CTLFLAG_NEEDGIANT, NULL, 0, sysctl_switch_tls, "", 3738 "Switch TCP connection to SW TLS"); 3739 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, switch_to_ifnet_tls, 3740 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | 3741 CTLFLAG_NEEDGIANT, NULL, 1, sysctl_switch_tls, "", 3742 "Switch TCP connection to ifnet TLS"); 3743 #endif 3744 3745 /* 3746 * Generate a standardized TCP log line for use throughout the 3747 * tcp subsystem. Memory allocation is done with M_NOWAIT to 3748 * allow use in the interrupt context. 3749 * 3750 * NB: The caller MUST free(s, M_TCPLOG) the returned string. 3751 * NB: The function may return NULL if memory allocation failed. 3752 * 3753 * Due to header inclusion and ordering limitations the struct ip 3754 * and ip6_hdr pointers have to be passed as void pointers. 3755 */ 3756 char * 3757 tcp_log_vain(struct in_conninfo *inc, struct tcphdr *th, const void *ip4hdr, 3758 const void *ip6hdr) 3759 { 3760 3761 /* Is logging enabled? */ 3762 if (V_tcp_log_in_vain == 0) 3763 return (NULL); 3764 3765 return (tcp_log_addr(inc, th, ip4hdr, ip6hdr)); 3766 } 3767 3768 char * 3769 tcp_log_addrs(struct in_conninfo *inc, struct tcphdr *th, const void *ip4hdr, 3770 const void *ip6hdr) 3771 { 3772 3773 /* Is logging enabled? */ 3774 if (tcp_log_debug == 0) 3775 return (NULL); 3776 3777 return (tcp_log_addr(inc, th, ip4hdr, ip6hdr)); 3778 } 3779 3780 static char * 3781 tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th, const void *ip4hdr, 3782 const void *ip6hdr) 3783 { 3784 char *s, *sp; 3785 size_t size; 3786 #ifdef INET 3787 const struct ip *ip = (const struct ip *)ip4hdr; 3788 #endif 3789 #ifdef INET6 3790 const struct ip6_hdr *ip6 = (const struct ip6_hdr *)ip6hdr; 3791 #endif /* INET6 */ 3792 3793 /* 3794 * The log line looks like this: 3795 * "TCP: [1.2.3.4]:50332 to [1.2.3.4]:80 tcpflags 0x2<SYN>" 3796 */ 3797 size = sizeof("TCP: []:12345 to []:12345 tcpflags 0x2<>") + 3798 sizeof(PRINT_TH_FLAGS) + 1 + 3799 #ifdef INET6 3800 2 * INET6_ADDRSTRLEN; 3801 #else 3802 2 * INET_ADDRSTRLEN; 3803 #endif /* INET6 */ 3804 3805 s = malloc(size, M_TCPLOG, M_ZERO|M_NOWAIT); 3806 if (s == NULL) 3807 return (NULL); 3808 3809 strcat(s, "TCP: ["); 3810 sp = s + strlen(s); 3811 3812 if (inc && ((inc->inc_flags & INC_ISIPV6) == 0)) { 3813 inet_ntoa_r(inc->inc_faddr, sp); 3814 sp = s + strlen(s); 3815 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport)); 3816 sp = s + strlen(s); 3817 inet_ntoa_r(inc->inc_laddr, sp); 3818 sp = s + strlen(s); 3819 sprintf(sp, "]:%i", ntohs(inc->inc_lport)); 3820 #ifdef INET6 3821 } else if (inc) { 3822 ip6_sprintf(sp, &inc->inc6_faddr); 3823 sp = s + strlen(s); 3824 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport)); 3825 sp = s + strlen(s); 3826 ip6_sprintf(sp, &inc->inc6_laddr); 3827 sp = s + strlen(s); 3828 sprintf(sp, "]:%i", ntohs(inc->inc_lport)); 3829 } else if (ip6 && th) { 3830 ip6_sprintf(sp, &ip6->ip6_src); 3831 sp = s + strlen(s); 3832 sprintf(sp, "]:%i to [", ntohs(th->th_sport)); 3833 sp = s + strlen(s); 3834 ip6_sprintf(sp, &ip6->ip6_dst); 3835 sp = s + strlen(s); 3836 sprintf(sp, "]:%i", ntohs(th->th_dport)); 3837 #endif /* INET6 */ 3838 #ifdef INET 3839 } else if (ip && th) { 3840 inet_ntoa_r(ip->ip_src, sp); 3841 sp = s + strlen(s); 3842 sprintf(sp, "]:%i to [", ntohs(th->th_sport)); 3843 sp = s + strlen(s); 3844 inet_ntoa_r(ip->ip_dst, sp); 3845 sp = s + strlen(s); 3846 sprintf(sp, "]:%i", ntohs(th->th_dport)); 3847 #endif /* INET */ 3848 } else { 3849 free(s, M_TCPLOG); 3850 return (NULL); 3851 } 3852 sp = s + strlen(s); 3853 if (th) 3854 sprintf(sp, " tcpflags 0x%b", tcp_get_flags(th), PRINT_TH_FLAGS); 3855 if (*(s + size - 1) != '\0') 3856 panic("%s: string too long", __func__); 3857 return (s); 3858 } 3859 3860 /* 3861 * A subroutine which makes it easy to track TCP state changes with DTrace. 3862 * This function shouldn't be called for t_state initializations that don't 3863 * correspond to actual TCP state transitions. 3864 */ 3865 void 3866 tcp_state_change(struct tcpcb *tp, int newstate) 3867 { 3868 #if defined(KDTRACE_HOOKS) 3869 int pstate = tp->t_state; 3870 #endif 3871 3872 TCPSTATES_DEC(tp->t_state); 3873 TCPSTATES_INC(newstate); 3874 tp->t_state = newstate; 3875 TCP_PROBE6(state__change, NULL, tp, NULL, tp, NULL, pstate); 3876 } 3877 3878 /* 3879 * Create an external-format (``xtcpcb'') structure using the information in 3880 * the kernel-format tcpcb structure pointed to by tp. This is done to 3881 * reduce the spew of irrelevant information over this interface, to isolate 3882 * user code from changes in the kernel structure, and potentially to provide 3883 * information-hiding if we decide that some of this information should be 3884 * hidden from users. 3885 */ 3886 void 3887 tcp_inptoxtp(const struct inpcb *inp, struct xtcpcb *xt) 3888 { 3889 struct tcpcb *tp = intotcpcb(inp); 3890 sbintime_t now; 3891 3892 bzero(xt, sizeof(*xt)); 3893 xt->t_state = tp->t_state; 3894 xt->t_logstate = tcp_get_bblog_state(tp); 3895 xt->t_flags = tp->t_flags; 3896 xt->t_sndzerowin = tp->t_sndzerowin; 3897 xt->t_sndrexmitpack = tp->t_sndrexmitpack; 3898 xt->t_rcvoopack = tp->t_rcvoopack; 3899 xt->t_rcv_wnd = tp->rcv_wnd; 3900 xt->t_snd_wnd = tp->snd_wnd; 3901 xt->t_snd_cwnd = tp->snd_cwnd; 3902 xt->t_snd_ssthresh = tp->snd_ssthresh; 3903 xt->t_dsack_bytes = tp->t_dsack_bytes; 3904 xt->t_dsack_tlp_bytes = tp->t_dsack_tlp_bytes; 3905 xt->t_dsack_pack = tp->t_dsack_pack; 3906 xt->t_maxseg = tp->t_maxseg; 3907 xt->xt_ecn = (tp->t_flags2 & TF2_ECN_PERMIT) ? 1 : 0 + 3908 (tp->t_flags2 & TF2_ACE_PERMIT) ? 2 : 0; 3909 3910 now = getsbinuptime(); 3911 #define COPYTIMER(which,where) do { \ 3912 if (tp->t_timers[which] != SBT_MAX) \ 3913 xt->where = (tp->t_timers[which] - now) / SBT_1MS; \ 3914 else \ 3915 xt->where = 0; \ 3916 } while (0) 3917 COPYTIMER(TT_DELACK, tt_delack); 3918 COPYTIMER(TT_REXMT, tt_rexmt); 3919 COPYTIMER(TT_PERSIST, tt_persist); 3920 COPYTIMER(TT_KEEP, tt_keep); 3921 COPYTIMER(TT_2MSL, tt_2msl); 3922 #undef COPYTIMER 3923 xt->t_rcvtime = 1000 * (ticks - tp->t_rcvtime) / hz; 3924 3925 xt->xt_encaps_port = tp->t_port; 3926 bcopy(tp->t_fb->tfb_tcp_block_name, xt->xt_stack, 3927 TCP_FUNCTION_NAME_LEN_MAX); 3928 bcopy(CC_ALGO(tp)->name, xt->xt_cc, TCP_CA_NAME_MAX); 3929 #ifdef TCP_BLACKBOX 3930 (void)tcp_log_get_id(tp, xt->xt_logid); 3931 #endif 3932 3933 xt->xt_len = sizeof(struct xtcpcb); 3934 in_pcbtoxinpcb(inp, &xt->xt_inp); 3935 } 3936 3937 void 3938 tcp_log_end_status(struct tcpcb *tp, uint8_t status) 3939 { 3940 uint32_t bit, i; 3941 3942 if ((tp == NULL) || 3943 (status > TCP_EI_STATUS_MAX_VALUE) || 3944 (status == 0)) { 3945 /* Invalid */ 3946 return; 3947 } 3948 if (status > (sizeof(uint32_t) * 8)) { 3949 /* Should this be a KASSERT? */ 3950 return; 3951 } 3952 bit = 1U << (status - 1); 3953 if (bit & tp->t_end_info_status) { 3954 /* already logged */ 3955 return; 3956 } 3957 for (i = 0; i < TCP_END_BYTE_INFO; i++) { 3958 if (tp->t_end_info_bytes[i] == TCP_EI_EMPTY_SLOT) { 3959 tp->t_end_info_bytes[i] = status; 3960 tp->t_end_info_status |= bit; 3961 break; 3962 } 3963 } 3964 } 3965 3966 int 3967 tcp_can_enable_pacing(void) 3968 { 3969 3970 if ((tcp_pacing_limit == -1) || 3971 (tcp_pacing_limit > number_of_tcp_connections_pacing)) { 3972 atomic_fetchadd_int(&number_of_tcp_connections_pacing, 1); 3973 shadow_num_connections = number_of_tcp_connections_pacing; 3974 return (1); 3975 } else { 3976 return (0); 3977 } 3978 } 3979 3980 static uint8_t tcp_pacing_warning = 0; 3981 3982 void 3983 tcp_decrement_paced_conn(void) 3984 { 3985 uint32_t ret; 3986 3987 ret = atomic_fetchadd_int(&number_of_tcp_connections_pacing, -1); 3988 shadow_num_connections = number_of_tcp_connections_pacing; 3989 KASSERT(ret != 0, ("tcp_paced_connection_exits -1 would cause wrap?")); 3990 if (ret == 0) { 3991 if (tcp_pacing_limit != -1) { 3992 printf("Warning all pacing is now disabled, count decrements invalidly!\n"); 3993 tcp_pacing_limit = 0; 3994 } else if (tcp_pacing_warning == 0) { 3995 printf("Warning pacing count is invalid, invalid decrement\n"); 3996 tcp_pacing_warning = 1; 3997 } 3998 } 3999 } 4000 4001 #ifdef TCP_ACCOUNTING 4002 int 4003 tcp_do_ack_accounting(struct tcpcb *tp, struct tcphdr *th, struct tcpopt *to, uint32_t tiwin, int mss) 4004 { 4005 if (SEQ_LT(th->th_ack, tp->snd_una)) { 4006 /* Do we have a SACK? */ 4007 if (to->to_flags & TOF_SACK) { 4008 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4009 tp->tcp_cnt_counters[ACK_SACK]++; 4010 } 4011 return (ACK_SACK); 4012 } else { 4013 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4014 tp->tcp_cnt_counters[ACK_BEHIND]++; 4015 } 4016 return (ACK_BEHIND); 4017 } 4018 } else if (th->th_ack == tp->snd_una) { 4019 /* Do we have a SACK? */ 4020 if (to->to_flags & TOF_SACK) { 4021 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4022 tp->tcp_cnt_counters[ACK_SACK]++; 4023 } 4024 return (ACK_SACK); 4025 } else if (tiwin != tp->snd_wnd) { 4026 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4027 tp->tcp_cnt_counters[ACK_RWND]++; 4028 } 4029 return (ACK_RWND); 4030 } else { 4031 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4032 tp->tcp_cnt_counters[ACK_DUPACK]++; 4033 } 4034 return (ACK_DUPACK); 4035 } 4036 } else { 4037 if (!SEQ_GT(th->th_ack, tp->snd_max)) { 4038 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4039 tp->tcp_cnt_counters[CNT_OF_ACKS_IN] += (((th->th_ack - tp->snd_una) + mss - 1)/mss); 4040 } 4041 } 4042 if (to->to_flags & TOF_SACK) { 4043 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4044 tp->tcp_cnt_counters[ACK_CUMACK_SACK]++; 4045 } 4046 return (ACK_CUMACK_SACK); 4047 } else { 4048 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4049 tp->tcp_cnt_counters[ACK_CUMACK]++; 4050 } 4051 return (ACK_CUMACK); 4052 } 4053 } 4054 } 4055 #endif 4056 4057 void 4058 tcp_change_time_units(struct tcpcb *tp, int granularity) 4059 { 4060 if (tp->t_tmr_granularity == granularity) { 4061 /* We are there */ 4062 return; 4063 } 4064 if (granularity == TCP_TMR_GRANULARITY_USEC) { 4065 KASSERT((tp->t_tmr_granularity == TCP_TMR_GRANULARITY_TICKS), 4066 ("Granularity is not TICKS its %u in tp:%p", 4067 tp->t_tmr_granularity, tp)); 4068 tp->t_rttlow = TICKS_2_USEC(tp->t_rttlow); 4069 if (tp->t_srtt > 1) { 4070 uint32_t val, frac; 4071 4072 val = tp->t_srtt >> TCP_RTT_SHIFT; 4073 frac = tp->t_srtt & 0x1f; 4074 tp->t_srtt = TICKS_2_USEC(val); 4075 /* 4076 * frac is the fractional part of the srtt (if any) 4077 * but its in ticks and every bit represents 4078 * 1/32nd of a hz. 4079 */ 4080 if (frac) { 4081 if (hz == 1000) { 4082 frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_MSEC) / (uint64_t)TCP_RTT_SCALE); 4083 } else { 4084 frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_SEC) / ((uint64_t)(hz) * (uint64_t)TCP_RTT_SCALE)); 4085 } 4086 tp->t_srtt += frac; 4087 } 4088 } 4089 if (tp->t_rttvar) { 4090 uint32_t val, frac; 4091 4092 val = tp->t_rttvar >> TCP_RTTVAR_SHIFT; 4093 frac = tp->t_rttvar & 0x1f; 4094 tp->t_rttvar = TICKS_2_USEC(val); 4095 /* 4096 * frac is the fractional part of the srtt (if any) 4097 * but its in ticks and every bit represents 4098 * 1/32nd of a hz. 4099 */ 4100 if (frac) { 4101 if (hz == 1000) { 4102 frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_MSEC) / (uint64_t)TCP_RTT_SCALE); 4103 } else { 4104 frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_SEC) / ((uint64_t)(hz) * (uint64_t)TCP_RTT_SCALE)); 4105 } 4106 tp->t_rttvar += frac; 4107 } 4108 } 4109 tp->t_tmr_granularity = TCP_TMR_GRANULARITY_USEC; 4110 } else if (granularity == TCP_TMR_GRANULARITY_TICKS) { 4111 /* Convert back to ticks, with */ 4112 KASSERT((tp->t_tmr_granularity == TCP_TMR_GRANULARITY_USEC), 4113 ("Granularity is not USEC its %u in tp:%p", 4114 tp->t_tmr_granularity, tp)); 4115 if (tp->t_srtt > 1) { 4116 uint32_t val, frac; 4117 4118 val = USEC_2_TICKS(tp->t_srtt); 4119 frac = tp->t_srtt % (HPTS_USEC_IN_SEC / hz); 4120 tp->t_srtt = val << TCP_RTT_SHIFT; 4121 /* 4122 * frac is the fractional part here is left 4123 * over from converting to hz and shifting. 4124 * We need to convert this to the 5 bit 4125 * remainder. 4126 */ 4127 if (frac) { 4128 if (hz == 1000) { 4129 frac = (((uint64_t)frac * (uint64_t)TCP_RTT_SCALE) / (uint64_t)HPTS_USEC_IN_MSEC); 4130 } else { 4131 frac = (((uint64_t)frac * (uint64_t)(hz) * (uint64_t)TCP_RTT_SCALE) /(uint64_t)HPTS_USEC_IN_SEC); 4132 } 4133 tp->t_srtt += frac; 4134 } 4135 } 4136 if (tp->t_rttvar) { 4137 uint32_t val, frac; 4138 4139 val = USEC_2_TICKS(tp->t_rttvar); 4140 frac = tp->t_srtt % (HPTS_USEC_IN_SEC / hz); 4141 tp->t_rttvar = val << TCP_RTTVAR_SHIFT; 4142 /* 4143 * frac is the fractional part here is left 4144 * over from converting to hz and shifting. 4145 * We need to convert this to the 5 bit 4146 * remainder. 4147 */ 4148 if (frac) { 4149 if (hz == 1000) { 4150 frac = (((uint64_t)frac * (uint64_t)TCP_RTT_SCALE) / (uint64_t)HPTS_USEC_IN_MSEC); 4151 } else { 4152 frac = (((uint64_t)frac * (uint64_t)(hz) * (uint64_t)TCP_RTT_SCALE) /(uint64_t)HPTS_USEC_IN_SEC); 4153 } 4154 tp->t_rttvar += frac; 4155 } 4156 } 4157 tp->t_rttlow = USEC_2_TICKS(tp->t_rttlow); 4158 tp->t_tmr_granularity = TCP_TMR_GRANULARITY_TICKS; 4159 } 4160 #ifdef INVARIANTS 4161 else { 4162 panic("Unknown granularity:%d tp:%p", 4163 granularity, tp); 4164 } 4165 #endif 4166 } 4167 4168 void 4169 tcp_handle_orphaned_packets(struct tcpcb *tp) 4170 { 4171 struct mbuf *save, *m, *prev; 4172 /* 4173 * Called when a stack switch is occuring from the fini() 4174 * of the old stack. We assue the init() as already been 4175 * run of the new stack and it has set the inp_flags2 to 4176 * what it supports. This function will then deal with any 4177 * differences i.e. cleanup packets that maybe queued that 4178 * the newstack does not support. 4179 */ 4180 4181 if (tptoinpcb(tp)->inp_flags2 & INP_MBUF_L_ACKS) 4182 return; 4183 if ((tptoinpcb(tp)->inp_flags2 & INP_SUPPORTS_MBUFQ) == 0) { 4184 /* 4185 * It is unsafe to process the packets since a 4186 * reset may be lurking in them (its rare but it 4187 * can occur). If we were to find a RST, then we 4188 * would end up dropping the connection and the 4189 * INP lock, so when we return the caller (tcp_usrreq) 4190 * will blow up when it trys to unlock the inp. 4191 * This new stack does not do any fancy LRO features 4192 * so all we can do is toss the packets. 4193 */ 4194 m = tp->t_in_pkt; 4195 tp->t_in_pkt = NULL; 4196 tp->t_tail_pkt = NULL; 4197 while (m) { 4198 save = m->m_nextpkt; 4199 m->m_nextpkt = NULL; 4200 m_freem(m); 4201 m = save; 4202 } 4203 } else { 4204 /* 4205 * Here we have a stack that does mbuf queuing but 4206 * does not support compressed ack's. We must 4207 * walk all the mbufs and discard any compressed acks. 4208 */ 4209 m = tp->t_in_pkt; 4210 prev = NULL; 4211 while (m) { 4212 if (m->m_flags & M_ACKCMP) { 4213 /* We must toss this packet */ 4214 if (tp->t_tail_pkt == m) 4215 tp->t_tail_pkt = prev; 4216 if (prev) 4217 prev->m_nextpkt = m->m_nextpkt; 4218 else 4219 tp->t_in_pkt = m->m_nextpkt; 4220 m->m_nextpkt = NULL; 4221 m_freem(m); 4222 /* move forward */ 4223 if (prev) 4224 m = prev->m_nextpkt; 4225 else 4226 m = tp->t_in_pkt; 4227 } else { 4228 /* this one is ok */ 4229 prev = m; 4230 m = m->m_nextpkt; 4231 } 4232 } 4233 } 4234 } 4235 4236 #ifdef TCP_REQUEST_TRK 4237 uint32_t 4238 tcp_estimate_tls_overhead(struct socket *so, uint64_t tls_usr_bytes) 4239 { 4240 #ifdef KERN_TLS 4241 struct ktls_session *tls; 4242 uint32_t rec_oh, records; 4243 4244 tls = so->so_snd.sb_tls_info; 4245 if (tls == NULL) 4246 return (0); 4247 4248 rec_oh = tls->params.tls_hlen + tls->params.tls_tlen; 4249 records = ((tls_usr_bytes + tls->params.max_frame_len - 1)/tls->params.max_frame_len); 4250 return (records * rec_oh); 4251 #else 4252 return (0); 4253 #endif 4254 } 4255 4256 extern uint32_t tcp_stale_entry_time; 4257 uint32_t tcp_stale_entry_time = 250000; 4258 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, usrlog_stale, CTLFLAG_RW, 4259 &tcp_stale_entry_time, 250000, "Time that a http entry without a sendfile ages out"); 4260 4261 void 4262 tcp_http_log_req_info(struct tcpcb *tp, struct http_sendfile_track *http, 4263 uint16_t slot, uint8_t val, uint64_t offset, uint64_t nbytes) 4264 { 4265 if (tcp_bblogging_on(tp)) { 4266 union tcp_log_stackspecific log; 4267 struct timeval tv; 4268 4269 memset(&log.u_bbr, 0, sizeof(log.u_bbr)); 4270 #ifdef TCPHPTS 4271 log.u_bbr.inhpts = tcp_in_hpts(tptoinpcb(tp)); 4272 #endif 4273 log.u_bbr.flex8 = val; 4274 log.u_bbr.rttProp = http->timestamp; 4275 log.u_bbr.delRate = http->start; 4276 log.u_bbr.cur_del_rate = http->end; 4277 log.u_bbr.flex1 = http->start_seq; 4278 log.u_bbr.flex2 = http->end_seq; 4279 log.u_bbr.flex3 = http->flags; 4280 log.u_bbr.flex4 = ((http->localtime >> 32) & 0x00000000ffffffff); 4281 log.u_bbr.flex5 = (http->localtime & 0x00000000ffffffff); 4282 log.u_bbr.flex7 = slot; 4283 log.u_bbr.bw_inuse = offset; 4284 /* nbytes = flex6 | epoch */ 4285 log.u_bbr.flex6 = ((nbytes >> 32) & 0x00000000ffffffff); 4286 log.u_bbr.epoch = (nbytes & 0x00000000ffffffff); 4287 /* cspr = lt_epoch | pkts_out */ 4288 log.u_bbr.lt_epoch = ((http->cspr >> 32) & 0x00000000ffffffff); 4289 log.u_bbr.pkts_out |= (http->cspr & 0x00000000ffffffff); 4290 log.u_bbr.applimited = tp->t_http_closed; 4291 log.u_bbr.applimited <<= 8; 4292 log.u_bbr.applimited |= tp->t_http_open; 4293 log.u_bbr.applimited <<= 8; 4294 log.u_bbr.applimited |= tp->t_http_req; 4295 log.u_bbr.timeStamp = tcp_get_usecs(&tv); 4296 TCP_LOG_EVENTP(tp, NULL, 4297 &tptosocket(tp)->so_rcv, 4298 &tptosocket(tp)->so_snd, 4299 TCP_LOG_HTTP_T, 0, 4300 0, &log, false, &tv); 4301 } 4302 } 4303 4304 void 4305 tcp_http_free_a_slot(struct tcpcb *tp, struct http_sendfile_track *ent) 4306 { 4307 if (tp->t_http_req > 0) 4308 tp->t_http_req--; 4309 if (ent->flags & TCP_HTTP_TRACK_FLG_OPEN) { 4310 if (tp->t_http_open > 0) 4311 tp->t_http_open--; 4312 } else { 4313 if (tp->t_http_closed > 0) 4314 tp->t_http_closed--; 4315 } 4316 ent->flags = TCP_HTTP_TRACK_FLG_EMPTY; 4317 } 4318 4319 static void 4320 tcp_http_check_for_stale_entries(struct tcpcb *tp, uint64_t ts, int rm_oldest) 4321 { 4322 struct http_sendfile_track *ent; 4323 uint64_t time_delta, oldest_delta; 4324 int i, oldest, oldest_set = 0, cnt_rm = 0; 4325 4326 for(i = 0; i < MAX_TCP_HTTP_REQ; i++) { 4327 ent = &tp->t_http_info[i]; 4328 if (ent->flags != TCP_HTTP_TRACK_FLG_USED) { 4329 /* 4330 * We only care about closed end ranges 4331 * that are allocated and have no sendfile 4332 * ever touching them. They would be in 4333 * state USED. 4334 */ 4335 continue; 4336 } 4337 if (ts >= ent->localtime) 4338 time_delta = ts - ent->localtime; 4339 else 4340 time_delta = 0; 4341 if (time_delta && 4342 ((oldest_delta < time_delta) || (oldest_set == 0))) { 4343 oldest_set = 1; 4344 oldest = i; 4345 oldest_delta = time_delta; 4346 } 4347 if (tcp_stale_entry_time && (time_delta >= tcp_stale_entry_time)) { 4348 /* 4349 * No sendfile in a our time-limit 4350 * time to purge it. 4351 */ 4352 cnt_rm++; 4353 tcp_http_log_req_info(tp, &tp->t_http_info[i], i, TCP_HTTP_REQ_LOG_STALE, 4354 time_delta, 0); 4355 tcp_http_free_a_slot(tp, ent); 4356 } 4357 } 4358 if ((cnt_rm == 0) && rm_oldest && oldest_set) { 4359 ent = &tp->t_http_info[oldest]; 4360 tcp_http_log_req_info(tp, &tp->t_http_info[i], i, TCP_HTTP_REQ_LOG_STALE, 4361 oldest_delta, 1); 4362 tcp_http_free_a_slot(tp, ent); 4363 } 4364 } 4365 4366 int 4367 tcp_http_check_for_comp(struct tcpcb *tp, tcp_seq ack_point) 4368 { 4369 int i, ret=0; 4370 struct http_sendfile_track *ent; 4371 4372 /* Clean up any old closed end requests that are now completed */ 4373 if (tp->t_http_req == 0) 4374 return(0); 4375 if (tp->t_http_closed == 0) 4376 return(0); 4377 for(i = 0; i < MAX_TCP_HTTP_REQ; i++) { 4378 ent = &tp->t_http_info[i]; 4379 /* Skip empty ones */ 4380 if (ent->flags == TCP_HTTP_TRACK_FLG_EMPTY) 4381 continue; 4382 /* Skip open ones */ 4383 if (ent->flags & TCP_HTTP_TRACK_FLG_OPEN) 4384 continue; 4385 if (SEQ_GEQ(ack_point, ent->end_seq)) { 4386 /* We are past it -- free it */ 4387 tcp_http_log_req_info(tp, ent, 4388 i, TCP_HTTP_REQ_LOG_FREED, 0, 0); 4389 tcp_http_free_a_slot(tp, ent); 4390 ret++; 4391 } 4392 } 4393 return (ret); 4394 } 4395 4396 int 4397 tcp_http_is_entry_comp(struct tcpcb *tp, struct http_sendfile_track *ent, tcp_seq ack_point) 4398 { 4399 if (tp->t_http_req == 0) 4400 return(-1); 4401 if (tp->t_http_closed == 0) 4402 return(-1); 4403 if (ent->flags == TCP_HTTP_TRACK_FLG_EMPTY) 4404 return(-1); 4405 if (SEQ_GEQ(ack_point, ent->end_seq)) { 4406 return (1); 4407 } 4408 return (0); 4409 } 4410 4411 struct http_sendfile_track * 4412 tcp_http_find_a_req_that_is_completed_by(struct tcpcb *tp, tcp_seq th_ack, int *ip) 4413 { 4414 /* 4415 * Given an ack point (th_ack) walk through our entries and 4416 * return the first one found that th_ack goes past the 4417 * end_seq. 4418 */ 4419 struct http_sendfile_track *ent; 4420 int i; 4421 4422 if (tp->t_http_req == 0) { 4423 /* none open */ 4424 return (NULL); 4425 } 4426 for(i = 0; i < MAX_TCP_HTTP_REQ; i++) { 4427 ent = &tp->t_http_info[i]; 4428 if (ent->flags == TCP_HTTP_TRACK_FLG_EMPTY) 4429 continue; 4430 if ((ent->flags & TCP_HTTP_TRACK_FLG_OPEN) == 0) { 4431 if (SEQ_GEQ(th_ack, ent->end_seq)) { 4432 *ip = i; 4433 return (ent); 4434 } 4435 } 4436 } 4437 return (NULL); 4438 } 4439 4440 struct http_sendfile_track * 4441 tcp_http_find_req_for_seq(struct tcpcb *tp, tcp_seq seq) 4442 { 4443 struct http_sendfile_track *ent; 4444 int i; 4445 4446 if (tp->t_http_req == 0) { 4447 /* none open */ 4448 return (NULL); 4449 } 4450 for(i = 0; i < MAX_TCP_HTTP_REQ; i++) { 4451 ent = &tp->t_http_info[i]; 4452 tcp_http_log_req_info(tp, ent, i, TCP_HTTP_REQ_LOG_SEARCH, 4453 (uint64_t)seq, 0); 4454 if (ent->flags == TCP_HTTP_TRACK_FLG_EMPTY) { 4455 continue; 4456 } 4457 if (ent->flags & TCP_HTTP_TRACK_FLG_OPEN) { 4458 /* 4459 * An open end request only needs to 4460 * match the beginning seq or be 4461 * all we have (once we keep going on 4462 * a open end request we may have a seq 4463 * wrap). 4464 */ 4465 if ((SEQ_GEQ(seq, ent->start_seq)) || 4466 (tp->t_http_closed == 0)) 4467 return (ent); 4468 } else { 4469 /* 4470 * For this one we need to 4471 * be a bit more careful if its 4472 * completed at least. 4473 */ 4474 if ((SEQ_GEQ(seq, ent->start_seq)) && 4475 (SEQ_LT(seq, ent->end_seq))) { 4476 return (ent); 4477 } 4478 } 4479 } 4480 return (NULL); 4481 } 4482 4483 /* Should this be in its own file tcp_http.c ? */ 4484 struct http_sendfile_track * 4485 tcp_http_alloc_req_full(struct tcpcb *tp, struct http_req *req, uint64_t ts, int rec_dups) 4486 { 4487 struct http_sendfile_track *fil; 4488 int i, allocated; 4489 4490 /* In case the stack does not check for completions do so now */ 4491 tcp_http_check_for_comp(tp, tp->snd_una); 4492 /* Check for stale entries */ 4493 if (tp->t_http_req) 4494 tcp_http_check_for_stale_entries(tp, ts, 4495 (tp->t_http_req >= MAX_TCP_HTTP_REQ)); 4496 /* Check to see if this is a duplicate of one not started */ 4497 if (tp->t_http_req) { 4498 for(i = 0, allocated = 0; i < MAX_TCP_HTTP_REQ; i++) { 4499 fil = &tp->t_http_info[i]; 4500 if (fil->flags != TCP_HTTP_TRACK_FLG_USED) 4501 continue; 4502 if ((fil->timestamp == req->timestamp) && 4503 (fil->start == req->start) && 4504 ((fil->flags & TCP_HTTP_TRACK_FLG_OPEN) || 4505 (fil->end == req->end))) { 4506 /* 4507 * We already have this request 4508 * and it has not been started with sendfile. 4509 * This probably means the user was returned 4510 * a 4xx of some sort and its going to age 4511 * out, lets not duplicate it. 4512 */ 4513 return(fil); 4514 } 4515 } 4516 } 4517 /* Ok if there is no room at the inn we are in trouble */ 4518 if (tp->t_http_req >= MAX_TCP_HTTP_REQ) { 4519 tcp_trace_point(tp, TCP_TP_HTTP_LOG_FAIL); 4520 for(i = 0; i < MAX_TCP_HTTP_REQ; i++) { 4521 tcp_http_log_req_info(tp, &tp->t_http_info[i], 4522 i, TCP_HTTP_REQ_LOG_ALLOCFAIL, 0, 0); 4523 } 4524 return (NULL); 4525 } 4526 for(i = 0, allocated = 0; i < MAX_TCP_HTTP_REQ; i++) { 4527 fil = &tp->t_http_info[i]; 4528 if (fil->flags == TCP_HTTP_TRACK_FLG_EMPTY) { 4529 allocated = 1; 4530 fil->flags = TCP_HTTP_TRACK_FLG_USED; 4531 fil->timestamp = req->timestamp; 4532 fil->localtime = ts; 4533 fil->start = req->start; 4534 if (req->flags & TCP_LOG_HTTPD_RANGE_END) { 4535 fil->end = req->end; 4536 } else { 4537 fil->end = 0; 4538 fil->flags |= TCP_HTTP_TRACK_FLG_OPEN; 4539 } 4540 /* 4541 * We can set the min boundaries to the TCP Sequence space, 4542 * but it might be found to be further up when sendfile 4543 * actually runs on this range (if it ever does). 4544 */ 4545 fil->sbcc_at_s = tptosocket(tp)->so_snd.sb_ccc; 4546 fil->start_seq = tp->snd_una + 4547 tptosocket(tp)->so_snd.sb_ccc; 4548 fil->end_seq = (fil->start_seq + ((uint32_t)(fil->end - fil->start))); 4549 if (tptosocket(tp)->so_snd.sb_tls_info) { 4550 /* 4551 * This session is doing TLS. Take a swag guess 4552 * at the overhead. 4553 */ 4554 fil->end_seq += tcp_estimate_tls_overhead( 4555 tptosocket(tp), (fil->end - fil->start)); 4556 } 4557 tp->t_http_req++; 4558 if (fil->flags & TCP_HTTP_TRACK_FLG_OPEN) 4559 tp->t_http_open++; 4560 else 4561 tp->t_http_closed++; 4562 tcp_http_log_req_info(tp, fil, i, 4563 TCP_HTTP_REQ_LOG_NEW, 0, 0); 4564 break; 4565 } else 4566 fil = NULL; 4567 } 4568 return (fil); 4569 } 4570 4571 void 4572 tcp_http_alloc_req(struct tcpcb *tp, union tcp_log_userdata *user, uint64_t ts) 4573 { 4574 (void)tcp_http_alloc_req_full(tp, &user->http_req, ts, 1); 4575 } 4576 #endif 4577 4578 void 4579 tcp_log_socket_option(struct tcpcb *tp, uint32_t option_num, uint32_t option_val, int err) 4580 { 4581 if (tcp_bblogging_on(tp)) { 4582 struct tcp_log_buffer *l; 4583 4584 l = tcp_log_event(tp, NULL, 4585 &tptosocket(tp)->so_rcv, 4586 &tptosocket(tp)->so_snd, 4587 TCP_LOG_SOCKET_OPT, 4588 err, 0, NULL, 1, 4589 NULL, NULL, 0, NULL); 4590 if (l) { 4591 l->tlb_flex1 = option_num; 4592 l->tlb_flex2 = option_val; 4593 } 4594 } 4595 } 4596