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 32 #include <sys/cdefs.h> 33 #include "opt_inet.h" 34 #include "opt_inet6.h" 35 #include "opt_ipsec.h" 36 #include "opt_kern_tls.h" 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/arb.h> 41 #include <sys/callout.h> 42 #include <sys/eventhandler.h> 43 #ifdef TCP_HHOOK 44 #include <sys/hhook.h> 45 #endif 46 #include <sys/kernel.h> 47 #ifdef TCP_HHOOK 48 #include <sys/khelp.h> 49 #endif 50 #ifdef KERN_TLS 51 #include <sys/ktls.h> 52 #endif 53 #include <sys/qmath.h> 54 #include <sys/stats.h> 55 #include <sys/sysctl.h> 56 #include <sys/jail.h> 57 #include <sys/malloc.h> 58 #include <sys/refcount.h> 59 #include <sys/mbuf.h> 60 #include <sys/priv.h> 61 #include <sys/proc.h> 62 #include <sys/sdt.h> 63 #include <sys/socket.h> 64 #include <sys/socketvar.h> 65 #include <sys/protosw.h> 66 #include <sys/random.h> 67 68 #include <vm/uma.h> 69 70 #include <net/route.h> 71 #include <net/route/nhop.h> 72 #include <net/if.h> 73 #include <net/if_var.h> 74 #include <net/if_private.h> 75 #include <net/vnet.h> 76 77 #include <netinet/in.h> 78 #include <netinet/in_fib.h> 79 #include <netinet/in_kdtrace.h> 80 #include <netinet/in_pcb.h> 81 #include <netinet/in_systm.h> 82 #include <netinet/in_var.h> 83 #include <netinet/ip.h> 84 #include <netinet/ip_icmp.h> 85 #include <netinet/ip_var.h> 86 #ifdef INET6 87 #include <netinet/icmp6.h> 88 #include <netinet/ip6.h> 89 #include <netinet6/in6_fib.h> 90 #include <netinet6/in6_pcb.h> 91 #include <netinet6/ip6_var.h> 92 #include <netinet6/scope6_var.h> 93 #include <netinet6/nd6.h> 94 #endif 95 96 #include <netinet/tcp.h> 97 #ifdef INVARIANTS 98 #define TCPSTATES 99 #endif 100 #include <netinet/tcp_fsm.h> 101 #include <netinet/tcp_seq.h> 102 #include <netinet/tcp_timer.h> 103 #include <netinet/tcp_var.h> 104 #include <netinet/tcp_ecn.h> 105 #include <netinet/tcp_log_buf.h> 106 #include <netinet/tcp_syncache.h> 107 #include <netinet/tcp_hpts.h> 108 #include <netinet/tcp_lro.h> 109 #include <netinet/cc/cc.h> 110 #include <netinet/tcpip.h> 111 #include <netinet/tcp_fastopen.h> 112 #include <netinet/tcp_accounting.h> 113 #ifdef TCPPCAP 114 #include <netinet/tcp_pcap.h> 115 #endif 116 #ifdef TCP_OFFLOAD 117 #include <netinet/tcp_offload.h> 118 #endif 119 #include <netinet/udp.h> 120 #include <netinet/udp_var.h> 121 #ifdef INET6 122 #include <netinet6/tcp6_var.h> 123 #endif 124 125 #include <netipsec/ipsec_support.h> 126 127 #include <machine/in_cksum.h> 128 #include <crypto/siphash/siphash.h> 129 130 #include <security/mac/mac_framework.h> 131 132 #ifdef INET6 133 static ip6proto_ctlinput_t tcp6_ctlinput; 134 static udp_tun_icmp_t tcp6_ctlinput_viaudp; 135 #endif 136 137 VNET_DEFINE(int, tcp_mssdflt) = TCP_MSS; 138 #ifdef INET6 139 VNET_DEFINE(int, tcp_v6mssdflt) = TCP6_MSS; 140 #endif 141 142 #ifdef TCP_SAD_DETECTION 143 /* Sack attack detection thresholds and such */ 144 SYSCTL_NODE(_net_inet_tcp, OID_AUTO, sack_attack, 145 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 146 "Sack Attack detection thresholds"); 147 int32_t tcp_force_detection = 0; 148 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, force_detection, 149 CTLFLAG_RW, 150 &tcp_force_detection, 0, 151 "Do we force detection even if the INP has it off?"); 152 int32_t tcp_sad_limit = 10000; 153 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, limit, 154 CTLFLAG_RW, 155 &tcp_sad_limit, 10000, 156 "If SaD is enabled, what is the limit to sendmap entries (0 = unlimited)?"); 157 int32_t tcp_sack_to_ack_thresh = 700; /* 70 % */ 158 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, sack_to_ack_thresh, 159 CTLFLAG_RW, 160 &tcp_sack_to_ack_thresh, 700, 161 "Percentage of sacks to acks we must see above (10.1 percent is 101)?"); 162 int32_t tcp_sack_to_move_thresh = 600; /* 60 % */ 163 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, move_thresh, 164 CTLFLAG_RW, 165 &tcp_sack_to_move_thresh, 600, 166 "Percentage of sack moves we must see above (10.1 percent is 101)"); 167 int32_t tcp_restoral_thresh = 450; /* 45 % (sack:2:ack -25%) (mv:ratio -15%) **/ 168 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, restore_thresh, 169 CTLFLAG_RW, 170 &tcp_restoral_thresh, 450, 171 "Percentage of sack to ack percentage we must see below to restore(10.1 percent is 101)"); 172 int32_t tcp_sad_decay_val = 800; 173 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, decay_per, 174 CTLFLAG_RW, 175 &tcp_sad_decay_val, 800, 176 "The decay percentage (10.1 percent equals 101 )"); 177 int32_t tcp_map_minimum = 500; 178 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, nummaps, 179 CTLFLAG_RW, 180 &tcp_map_minimum, 500, 181 "Number of Map enteries before we start detection"); 182 int32_t tcp_sad_pacing_interval = 2000; 183 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, sad_pacing_int, 184 CTLFLAG_RW, 185 &tcp_sad_pacing_interval, 2000, 186 "What is the minimum pacing interval for a classified attacker?"); 187 188 int32_t tcp_sad_low_pps = 100; 189 SYSCTL_INT(_net_inet_tcp_sack_attack, OID_AUTO, sad_low_pps, 190 CTLFLAG_RW, 191 &tcp_sad_low_pps, 100, 192 "What is the input pps that below which we do not decay?"); 193 #endif 194 uint32_t tcp_ack_war_time_window = 1000; 195 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, ack_war_timewindow, 196 CTLFLAG_RW, 197 &tcp_ack_war_time_window, 1000, 198 "If the tcp_stack does ack-war prevention how many milliseconds are in its time window?"); 199 uint32_t tcp_ack_war_cnt = 5; 200 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, ack_war_cnt, 201 CTLFLAG_RW, 202 &tcp_ack_war_cnt, 5, 203 "If the tcp_stack does ack-war prevention how many acks can be sent in its time window?"); 204 205 struct rwlock tcp_function_lock; 206 207 static int 208 sysctl_net_inet_tcp_mss_check(SYSCTL_HANDLER_ARGS) 209 { 210 int error, new; 211 212 new = V_tcp_mssdflt; 213 error = sysctl_handle_int(oidp, &new, 0, req); 214 if (error == 0 && req->newptr) { 215 if (new < TCP_MINMSS) 216 error = EINVAL; 217 else 218 V_tcp_mssdflt = new; 219 } 220 return (error); 221 } 222 223 SYSCTL_PROC(_net_inet_tcp, TCPCTL_MSSDFLT, mssdflt, 224 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 225 &VNET_NAME(tcp_mssdflt), 0, &sysctl_net_inet_tcp_mss_check, "I", 226 "Default TCP Maximum Segment Size"); 227 228 #ifdef INET6 229 static int 230 sysctl_net_inet_tcp_mss_v6_check(SYSCTL_HANDLER_ARGS) 231 { 232 int error, new; 233 234 new = V_tcp_v6mssdflt; 235 error = sysctl_handle_int(oidp, &new, 0, req); 236 if (error == 0 && req->newptr) { 237 if (new < TCP_MINMSS) 238 error = EINVAL; 239 else 240 V_tcp_v6mssdflt = new; 241 } 242 return (error); 243 } 244 245 SYSCTL_PROC(_net_inet_tcp, TCPCTL_V6MSSDFLT, v6mssdflt, 246 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 247 &VNET_NAME(tcp_v6mssdflt), 0, &sysctl_net_inet_tcp_mss_v6_check, "I", 248 "Default TCP Maximum Segment Size for IPv6"); 249 #endif /* INET6 */ 250 251 /* 252 * Minimum MSS we accept and use. This prevents DoS attacks where 253 * we are forced to a ridiculous low MSS like 20 and send hundreds 254 * of packets instead of one. The effect scales with the available 255 * bandwidth and quickly saturates the CPU and network interface 256 * with packet generation and sending. Set to zero to disable MINMSS 257 * checking. This setting prevents us from sending too small packets. 258 */ 259 VNET_DEFINE(int, tcp_minmss) = TCP_MINMSS; 260 SYSCTL_INT(_net_inet_tcp, OID_AUTO, minmss, CTLFLAG_VNET | CTLFLAG_RW, 261 &VNET_NAME(tcp_minmss), 0, 262 "Minimum TCP Maximum Segment Size"); 263 264 VNET_DEFINE(int, tcp_do_rfc1323) = 1; 265 SYSCTL_INT(_net_inet_tcp, TCPCTL_DO_RFC1323, rfc1323, CTLFLAG_VNET | CTLFLAG_RW, 266 &VNET_NAME(tcp_do_rfc1323), 0, 267 "Enable rfc1323 (high performance TCP) extensions"); 268 269 /* 270 * As of June 2021, several TCP stacks violate RFC 7323 from September 2014. 271 * Some stacks negotiate TS, but never send them after connection setup. Some 272 * stacks negotiate TS, but don't send them when sending keep-alive segments. 273 * These include modern widely deployed TCP stacks. 274 * Therefore tolerating violations for now... 275 */ 276 VNET_DEFINE(int, tcp_tolerate_missing_ts) = 1; 277 SYSCTL_INT(_net_inet_tcp, OID_AUTO, tolerate_missing_ts, CTLFLAG_VNET | CTLFLAG_RW, 278 &VNET_NAME(tcp_tolerate_missing_ts), 0, 279 "Tolerate missing TCP timestamps"); 280 281 VNET_DEFINE(int, tcp_ts_offset_per_conn) = 1; 282 SYSCTL_INT(_net_inet_tcp, OID_AUTO, ts_offset_per_conn, CTLFLAG_VNET | CTLFLAG_RW, 283 &VNET_NAME(tcp_ts_offset_per_conn), 0, 284 "Initialize TCP timestamps per connection instead of per host pair"); 285 286 /* How many connections are pacing */ 287 static volatile uint32_t number_of_tcp_connections_pacing = 0; 288 static uint32_t shadow_num_connections = 0; 289 static counter_u64_t tcp_pacing_failures; 290 291 static int tcp_pacing_limit = 10000; 292 SYSCTL_INT(_net_inet_tcp, OID_AUTO, pacing_limit, CTLFLAG_RW, 293 &tcp_pacing_limit, 1000, 294 "If the TCP stack does pacing, is there a limit (-1 = no, 0 = no pacing N = number of connections)"); 295 296 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, pacing_count, CTLFLAG_RD, 297 &shadow_num_connections, 0, "Number of TCP connections being paced"); 298 299 SYSCTL_COUNTER_U64(_net_inet_tcp, OID_AUTO, pacing_failures, CTLFLAG_RD, 300 &tcp_pacing_failures, "Number of times we failed to enable pacing to avoid exceeding the limit"); 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 /* 307 * Target size of TCP PCB hash tables. Must be a power of two. 308 * 309 * Note that this can be overridden by the kernel environment 310 * variable net.inet.tcp.tcbhashsize 311 */ 312 #ifndef TCBHASHSIZE 313 #define TCBHASHSIZE 0 314 #endif 315 static int tcp_tcbhashsize = TCBHASHSIZE; 316 SYSCTL_INT(_net_inet_tcp, OID_AUTO, tcbhashsize, CTLFLAG_RDTUN, 317 &tcp_tcbhashsize, 0, "Size of TCP control-block hashtable"); 318 319 static int do_tcpdrain = 1; 320 SYSCTL_INT(_net_inet_tcp, OID_AUTO, do_tcpdrain, CTLFLAG_RW, &do_tcpdrain, 0, 321 "Enable tcp_drain routine for extra help when low on mbufs"); 322 323 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, pcbcount, CTLFLAG_VNET | CTLFLAG_RD, 324 &VNET_NAME(tcbinfo.ipi_count), 0, "Number of active PCBs"); 325 326 VNET_DEFINE_STATIC(int, icmp_may_rst) = 1; 327 #define V_icmp_may_rst VNET(icmp_may_rst) 328 SYSCTL_INT(_net_inet_tcp, OID_AUTO, icmp_may_rst, CTLFLAG_VNET | CTLFLAG_RW, 329 &VNET_NAME(icmp_may_rst), 0, 330 "Certain ICMP unreachable messages may abort connections in SYN_SENT"); 331 332 VNET_DEFINE_STATIC(int, tcp_isn_reseed_interval) = 0; 333 #define V_tcp_isn_reseed_interval VNET(tcp_isn_reseed_interval) 334 SYSCTL_INT(_net_inet_tcp, OID_AUTO, isn_reseed_interval, CTLFLAG_VNET | CTLFLAG_RW, 335 &VNET_NAME(tcp_isn_reseed_interval), 0, 336 "Seconds between reseeding of ISN secret"); 337 338 static int tcp_soreceive_stream; 339 SYSCTL_INT(_net_inet_tcp, OID_AUTO, soreceive_stream, CTLFLAG_RDTUN, 340 &tcp_soreceive_stream, 0, "Using soreceive_stream for TCP sockets"); 341 342 VNET_DEFINE(uma_zone_t, sack_hole_zone); 343 #define V_sack_hole_zone VNET(sack_hole_zone) 344 VNET_DEFINE(uint32_t, tcp_map_entries_limit) = 0; /* unlimited */ 345 static int 346 sysctl_net_inet_tcp_map_limit_check(SYSCTL_HANDLER_ARGS) 347 { 348 int error; 349 uint32_t new; 350 351 new = V_tcp_map_entries_limit; 352 error = sysctl_handle_int(oidp, &new, 0, req); 353 if (error == 0 && req->newptr) { 354 /* only allow "0" and value > minimum */ 355 if (new > 0 && new < TCP_MIN_MAP_ENTRIES_LIMIT) 356 error = EINVAL; 357 else 358 V_tcp_map_entries_limit = new; 359 } 360 return (error); 361 } 362 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, map_limit, 363 CTLFLAG_VNET | CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 364 &VNET_NAME(tcp_map_entries_limit), 0, 365 &sysctl_net_inet_tcp_map_limit_check, "IU", 366 "Total sendmap entries limit"); 367 368 VNET_DEFINE(uint32_t, tcp_map_split_limit) = 0; /* unlimited */ 369 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, split_limit, CTLFLAG_VNET | CTLFLAG_RW, 370 &VNET_NAME(tcp_map_split_limit), 0, 371 "Total sendmap split entries limit"); 372 373 #ifdef TCP_HHOOK 374 VNET_DEFINE(struct hhook_head *, tcp_hhh[HHOOK_TCP_LAST+1]); 375 #endif 376 377 #define TS_OFFSET_SECRET_LENGTH SIPHASH_KEY_LENGTH 378 VNET_DEFINE_STATIC(u_char, ts_offset_secret[TS_OFFSET_SECRET_LENGTH]); 379 #define V_ts_offset_secret VNET(ts_offset_secret) 380 381 static int tcp_default_fb_init(struct tcpcb *tp, void **ptr); 382 static void tcp_default_fb_fini(struct tcpcb *tp, int tcb_is_purged); 383 static int tcp_default_handoff_ok(struct tcpcb *tp); 384 static struct inpcb *tcp_notify(struct inpcb *, int); 385 static struct inpcb *tcp_mtudisc_notify(struct inpcb *, int); 386 static struct inpcb *tcp_mtudisc(struct inpcb *, int); 387 static struct inpcb *tcp_drop_syn_sent(struct inpcb *, int); 388 static char * tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th, 389 const void *ip4hdr, const void *ip6hdr); 390 static void tcp_default_switch_failed(struct tcpcb *tp); 391 static ipproto_ctlinput_t tcp_ctlinput; 392 static udp_tun_icmp_t tcp_ctlinput_viaudp; 393 394 static struct tcp_function_block tcp_def_funcblk = { 395 .tfb_tcp_block_name = "freebsd", 396 .tfb_tcp_output = tcp_default_output, 397 .tfb_tcp_do_segment = tcp_do_segment, 398 .tfb_tcp_ctloutput = tcp_default_ctloutput, 399 .tfb_tcp_handoff_ok = tcp_default_handoff_ok, 400 .tfb_tcp_fb_init = tcp_default_fb_init, 401 .tfb_tcp_fb_fini = tcp_default_fb_fini, 402 .tfb_switch_failed = tcp_default_switch_failed, 403 }; 404 405 static int tcp_fb_cnt = 0; 406 struct tcp_funchead t_functions; 407 VNET_DEFINE_STATIC(struct tcp_function_block *, tcp_func_set_ptr) = &tcp_def_funcblk; 408 #define V_tcp_func_set_ptr VNET(tcp_func_set_ptr) 409 410 void 411 tcp_record_dsack(struct tcpcb *tp, tcp_seq start, tcp_seq end, int tlp) 412 { 413 TCPSTAT_INC(tcps_dsack_count); 414 tp->t_dsack_pack++; 415 if (tlp == 0) { 416 if (SEQ_GT(end, start)) { 417 tp->t_dsack_bytes += (end - start); 418 TCPSTAT_ADD(tcps_dsack_bytes, (end - start)); 419 } else { 420 tp->t_dsack_tlp_bytes += (start - end); 421 TCPSTAT_ADD(tcps_dsack_bytes, (start - end)); 422 } 423 } else { 424 if (SEQ_GT(end, start)) { 425 tp->t_dsack_bytes += (end - start); 426 TCPSTAT_ADD(tcps_dsack_tlp_bytes, (end - start)); 427 } else { 428 tp->t_dsack_tlp_bytes += (start - end); 429 TCPSTAT_ADD(tcps_dsack_tlp_bytes, (start - end)); 430 } 431 } 432 } 433 434 static struct tcp_function_block * 435 find_tcp_functions_locked(struct tcp_function_set *fs) 436 { 437 struct tcp_function *f; 438 struct tcp_function_block *blk=NULL; 439 440 TAILQ_FOREACH(f, &t_functions, tf_next) { 441 if (strcmp(f->tf_name, fs->function_set_name) == 0) { 442 blk = f->tf_fb; 443 break; 444 } 445 } 446 return(blk); 447 } 448 449 static struct tcp_function_block * 450 find_tcp_fb_locked(struct tcp_function_block *blk, struct tcp_function **s) 451 { 452 struct tcp_function_block *rblk=NULL; 453 struct tcp_function *f; 454 455 TAILQ_FOREACH(f, &t_functions, tf_next) { 456 if (f->tf_fb == blk) { 457 rblk = blk; 458 if (s) { 459 *s = f; 460 } 461 break; 462 } 463 } 464 return (rblk); 465 } 466 467 struct tcp_function_block * 468 find_and_ref_tcp_functions(struct tcp_function_set *fs) 469 { 470 struct tcp_function_block *blk; 471 472 rw_rlock(&tcp_function_lock); 473 blk = find_tcp_functions_locked(fs); 474 if (blk) 475 refcount_acquire(&blk->tfb_refcnt); 476 rw_runlock(&tcp_function_lock); 477 return(blk); 478 } 479 480 struct tcp_function_block * 481 find_and_ref_tcp_fb(struct tcp_function_block *blk) 482 { 483 struct tcp_function_block *rblk; 484 485 rw_rlock(&tcp_function_lock); 486 rblk = find_tcp_fb_locked(blk, NULL); 487 if (rblk) 488 refcount_acquire(&rblk->tfb_refcnt); 489 rw_runlock(&tcp_function_lock); 490 return(rblk); 491 } 492 493 /* Find a matching alias for the given tcp_function_block. */ 494 int 495 find_tcp_function_alias(struct tcp_function_block *blk, 496 struct tcp_function_set *fs) 497 { 498 struct tcp_function *f; 499 int found; 500 501 found = 0; 502 rw_rlock(&tcp_function_lock); 503 TAILQ_FOREACH(f, &t_functions, tf_next) { 504 if ((f->tf_fb == blk) && 505 (strncmp(f->tf_name, blk->tfb_tcp_block_name, 506 TCP_FUNCTION_NAME_LEN_MAX) != 0)) { 507 /* Matching function block with different name. */ 508 strncpy(fs->function_set_name, f->tf_name, 509 TCP_FUNCTION_NAME_LEN_MAX); 510 found = 1; 511 break; 512 } 513 } 514 /* Null terminate the string appropriately. */ 515 if (found) { 516 fs->function_set_name[TCP_FUNCTION_NAME_LEN_MAX - 1] = '\0'; 517 } else { 518 fs->function_set_name[0] = '\0'; 519 } 520 rw_runlock(&tcp_function_lock); 521 return (found); 522 } 523 524 static struct tcp_function_block * 525 find_and_ref_tcp_default_fb(void) 526 { 527 struct tcp_function_block *rblk; 528 529 rw_rlock(&tcp_function_lock); 530 rblk = V_tcp_func_set_ptr; 531 refcount_acquire(&rblk->tfb_refcnt); 532 rw_runlock(&tcp_function_lock); 533 return (rblk); 534 } 535 536 void 537 tcp_switch_back_to_default(struct tcpcb *tp) 538 { 539 struct tcp_function_block *tfb; 540 void *ptr = NULL; 541 542 KASSERT(tp->t_fb != &tcp_def_funcblk, 543 ("%s: called by the built-in default stack", __func__)); 544 545 if (tp->t_fb->tfb_tcp_timer_stop_all != NULL) 546 tp->t_fb->tfb_tcp_timer_stop_all(tp); 547 548 /* 549 * Now, we'll find a new function block to use. 550 * Start by trying the current user-selected 551 * default, unless this stack is the user-selected 552 * default. 553 */ 554 tfb = find_and_ref_tcp_default_fb(); 555 if (tfb == tp->t_fb) { 556 refcount_release(&tfb->tfb_refcnt); 557 tfb = NULL; 558 } 559 /* Does the stack accept this connection? */ 560 if (tfb != NULL && tfb->tfb_tcp_handoff_ok != NULL && 561 (*tfb->tfb_tcp_handoff_ok)(tp)) { 562 refcount_release(&tfb->tfb_refcnt); 563 tfb = NULL; 564 } 565 /* Try to use that stack. */ 566 if (tfb != NULL) { 567 /* Initialize the new stack. If it succeeds, we are done. */ 568 if (tfb->tfb_tcp_fb_init == NULL || 569 (*tfb->tfb_tcp_fb_init)(tp, &ptr) == 0) { 570 /* Release the old stack */ 571 if (tp->t_fb->tfb_tcp_fb_fini != NULL) 572 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 0); 573 refcount_release(&tp->t_fb->tfb_refcnt); 574 /* Now set in all the pointers */ 575 tp->t_fb = tfb; 576 tp->t_fb_ptr = ptr; 577 return; 578 } 579 /* 580 * Initialization failed. Release the reference count on 581 * the looked up default stack. 582 */ 583 refcount_release(&tfb->tfb_refcnt); 584 } 585 586 /* 587 * If that wasn't feasible, use the built-in default 588 * stack which is not allowed to reject anyone. 589 */ 590 tfb = find_and_ref_tcp_fb(&tcp_def_funcblk); 591 if (tfb == NULL) { 592 /* there always should be a default */ 593 panic("Can't refer to tcp_def_funcblk"); 594 } 595 if (tfb->tfb_tcp_handoff_ok != NULL) { 596 if ((*tfb->tfb_tcp_handoff_ok) (tp)) { 597 /* The default stack cannot say no */ 598 panic("Default stack rejects a new session?"); 599 } 600 } 601 if (tfb->tfb_tcp_fb_init != NULL && 602 (*tfb->tfb_tcp_fb_init)(tp, &ptr)) { 603 /* The default stack cannot fail */ 604 panic("Default stack initialization failed"); 605 } 606 /* Now release the old stack */ 607 if (tp->t_fb->tfb_tcp_fb_fini != NULL) 608 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 0); 609 refcount_release(&tp->t_fb->tfb_refcnt); 610 /* And set in the pointers to the new */ 611 tp->t_fb = tfb; 612 tp->t_fb_ptr = ptr; 613 } 614 615 static bool 616 tcp_recv_udp_tunneled_packet(struct mbuf *m, int off, struct inpcb *inp, 617 const struct sockaddr *sa, void *ctx) 618 { 619 struct ip *iph; 620 #ifdef INET6 621 struct ip6_hdr *ip6; 622 #endif 623 struct udphdr *uh; 624 struct tcphdr *th; 625 int thlen; 626 uint16_t port; 627 628 TCPSTAT_INC(tcps_tunneled_pkts); 629 if ((m->m_flags & M_PKTHDR) == 0) { 630 /* Can't handle one that is not a pkt hdr */ 631 TCPSTAT_INC(tcps_tunneled_errs); 632 goto out; 633 } 634 thlen = sizeof(struct tcphdr); 635 if (m->m_len < off + sizeof(struct udphdr) + thlen && 636 (m = m_pullup(m, off + sizeof(struct udphdr) + thlen)) == NULL) { 637 TCPSTAT_INC(tcps_tunneled_errs); 638 goto out; 639 } 640 iph = mtod(m, struct ip *); 641 uh = (struct udphdr *)((caddr_t)iph + off); 642 th = (struct tcphdr *)(uh + 1); 643 thlen = th->th_off << 2; 644 if (m->m_len < off + sizeof(struct udphdr) + thlen) { 645 m = m_pullup(m, off + sizeof(struct udphdr) + thlen); 646 if (m == NULL) { 647 TCPSTAT_INC(tcps_tunneled_errs); 648 goto out; 649 } else { 650 iph = mtod(m, struct ip *); 651 uh = (struct udphdr *)((caddr_t)iph + off); 652 th = (struct tcphdr *)(uh + 1); 653 } 654 } 655 m->m_pkthdr.tcp_tun_port = port = uh->uh_sport; 656 bcopy(th, uh, m->m_len - off); 657 m->m_len -= sizeof(struct udphdr); 658 m->m_pkthdr.len -= sizeof(struct udphdr); 659 /* 660 * We use the same algorithm for 661 * both UDP and TCP for c-sum. So 662 * the code in tcp_input will skip 663 * the checksum. So we do nothing 664 * with the flag (m->m_pkthdr.csum_flags). 665 */ 666 switch (iph->ip_v) { 667 #ifdef INET 668 case IPVERSION: 669 iph->ip_len = htons(ntohs(iph->ip_len) - sizeof(struct udphdr)); 670 tcp_input_with_port(&m, &off, IPPROTO_TCP, port); 671 break; 672 #endif 673 #ifdef INET6 674 case IPV6_VERSION >> 4: 675 ip6 = mtod(m, struct ip6_hdr *); 676 ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - sizeof(struct udphdr)); 677 tcp6_input_with_port(&m, &off, IPPROTO_TCP, port); 678 break; 679 #endif 680 default: 681 goto out; 682 break; 683 } 684 return (true); 685 out: 686 m_freem(m); 687 688 return (true); 689 } 690 691 static int 692 sysctl_net_inet_default_tcp_functions(SYSCTL_HANDLER_ARGS) 693 { 694 int error=ENOENT; 695 struct tcp_function_set fs; 696 struct tcp_function_block *blk; 697 698 memset(&fs, 0, sizeof(fs)); 699 rw_rlock(&tcp_function_lock); 700 blk = find_tcp_fb_locked(V_tcp_func_set_ptr, NULL); 701 if (blk) { 702 /* Found him */ 703 strcpy(fs.function_set_name, blk->tfb_tcp_block_name); 704 fs.pcbcnt = blk->tfb_refcnt; 705 } 706 rw_runlock(&tcp_function_lock); 707 error = sysctl_handle_string(oidp, fs.function_set_name, 708 sizeof(fs.function_set_name), req); 709 710 /* Check for error or no change */ 711 if (error != 0 || req->newptr == NULL) 712 return(error); 713 714 rw_wlock(&tcp_function_lock); 715 blk = find_tcp_functions_locked(&fs); 716 if ((blk == NULL) || 717 (blk->tfb_flags & TCP_FUNC_BEING_REMOVED)) { 718 error = ENOENT; 719 goto done; 720 } 721 V_tcp_func_set_ptr = blk; 722 done: 723 rw_wunlock(&tcp_function_lock); 724 return (error); 725 } 726 727 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, functions_default, 728 CTLFLAG_VNET | CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 729 NULL, 0, sysctl_net_inet_default_tcp_functions, "A", 730 "Set/get the default TCP functions"); 731 732 static int 733 sysctl_net_inet_list_available(SYSCTL_HANDLER_ARGS) 734 { 735 int error, cnt, linesz; 736 struct tcp_function *f; 737 char *buffer, *cp; 738 size_t bufsz, outsz; 739 bool alias; 740 741 cnt = 0; 742 rw_rlock(&tcp_function_lock); 743 TAILQ_FOREACH(f, &t_functions, tf_next) { 744 cnt++; 745 } 746 rw_runlock(&tcp_function_lock); 747 748 bufsz = (cnt+2) * ((TCP_FUNCTION_NAME_LEN_MAX * 2) + 13) + 1; 749 buffer = malloc(bufsz, M_TEMP, M_WAITOK); 750 751 error = 0; 752 cp = buffer; 753 754 linesz = snprintf(cp, bufsz, "\n%-32s%c %-32s %s\n", "Stack", 'D', 755 "Alias", "PCB count"); 756 cp += linesz; 757 bufsz -= linesz; 758 outsz = linesz; 759 760 rw_rlock(&tcp_function_lock); 761 TAILQ_FOREACH(f, &t_functions, tf_next) { 762 alias = (f->tf_name != f->tf_fb->tfb_tcp_block_name); 763 linesz = snprintf(cp, bufsz, "%-32s%c %-32s %u\n", 764 f->tf_fb->tfb_tcp_block_name, 765 (f->tf_fb == V_tcp_func_set_ptr) ? '*' : ' ', 766 alias ? f->tf_name : "-", 767 f->tf_fb->tfb_refcnt); 768 if (linesz >= bufsz) { 769 error = EOVERFLOW; 770 break; 771 } 772 cp += linesz; 773 bufsz -= linesz; 774 outsz += linesz; 775 } 776 rw_runlock(&tcp_function_lock); 777 if (error == 0) 778 error = sysctl_handle_string(oidp, buffer, outsz + 1, req); 779 free(buffer, M_TEMP); 780 return (error); 781 } 782 783 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, functions_available, 784 CTLFLAG_VNET | CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT, 785 NULL, 0, sysctl_net_inet_list_available, "A", 786 "list available TCP Function sets"); 787 788 VNET_DEFINE(int, tcp_udp_tunneling_port) = TCP_TUNNELING_PORT_DEFAULT; 789 790 #ifdef INET 791 VNET_DEFINE(struct socket *, udp4_tun_socket) = NULL; 792 #define V_udp4_tun_socket VNET(udp4_tun_socket) 793 #endif 794 #ifdef INET6 795 VNET_DEFINE(struct socket *, udp6_tun_socket) = NULL; 796 #define V_udp6_tun_socket VNET(udp6_tun_socket) 797 #endif 798 799 static struct sx tcpoudp_lock; 800 801 static void 802 tcp_over_udp_stop(void) 803 { 804 805 sx_assert(&tcpoudp_lock, SA_XLOCKED); 806 807 #ifdef INET 808 if (V_udp4_tun_socket != NULL) { 809 soclose(V_udp4_tun_socket); 810 V_udp4_tun_socket = NULL; 811 } 812 #endif 813 #ifdef INET6 814 if (V_udp6_tun_socket != NULL) { 815 soclose(V_udp6_tun_socket); 816 V_udp6_tun_socket = NULL; 817 } 818 #endif 819 } 820 821 static int 822 tcp_over_udp_start(void) 823 { 824 uint16_t port; 825 int ret; 826 #ifdef INET 827 struct sockaddr_in sin; 828 #endif 829 #ifdef INET6 830 struct sockaddr_in6 sin6; 831 #endif 832 833 sx_assert(&tcpoudp_lock, SA_XLOCKED); 834 835 port = V_tcp_udp_tunneling_port; 836 if (ntohs(port) == 0) { 837 /* Must have a port set */ 838 return (EINVAL); 839 } 840 #ifdef INET 841 if (V_udp4_tun_socket != NULL) { 842 /* Already running -- must stop first */ 843 return (EALREADY); 844 } 845 #endif 846 #ifdef INET6 847 if (V_udp6_tun_socket != NULL) { 848 /* Already running -- must stop first */ 849 return (EALREADY); 850 } 851 #endif 852 #ifdef INET 853 if ((ret = socreate(PF_INET, &V_udp4_tun_socket, 854 SOCK_DGRAM, IPPROTO_UDP, 855 curthread->td_ucred, curthread))) { 856 tcp_over_udp_stop(); 857 return (ret); 858 } 859 /* Call the special UDP hook. */ 860 if ((ret = udp_set_kernel_tunneling(V_udp4_tun_socket, 861 tcp_recv_udp_tunneled_packet, 862 tcp_ctlinput_viaudp, 863 NULL))) { 864 tcp_over_udp_stop(); 865 return (ret); 866 } 867 /* Ok, we have a socket, bind it to the port. */ 868 memset(&sin, 0, sizeof(struct sockaddr_in)); 869 sin.sin_len = sizeof(struct sockaddr_in); 870 sin.sin_family = AF_INET; 871 sin.sin_port = htons(port); 872 if ((ret = sobind(V_udp4_tun_socket, 873 (struct sockaddr *)&sin, curthread))) { 874 tcp_over_udp_stop(); 875 return (ret); 876 } 877 #endif 878 #ifdef INET6 879 if ((ret = socreate(PF_INET6, &V_udp6_tun_socket, 880 SOCK_DGRAM, IPPROTO_UDP, 881 curthread->td_ucred, curthread))) { 882 tcp_over_udp_stop(); 883 return (ret); 884 } 885 /* Call the special UDP hook. */ 886 if ((ret = udp_set_kernel_tunneling(V_udp6_tun_socket, 887 tcp_recv_udp_tunneled_packet, 888 tcp6_ctlinput_viaudp, 889 NULL))) { 890 tcp_over_udp_stop(); 891 return (ret); 892 } 893 /* Ok, we have a socket, bind it to the port. */ 894 memset(&sin6, 0, sizeof(struct sockaddr_in6)); 895 sin6.sin6_len = sizeof(struct sockaddr_in6); 896 sin6.sin6_family = AF_INET6; 897 sin6.sin6_port = htons(port); 898 if ((ret = sobind(V_udp6_tun_socket, 899 (struct sockaddr *)&sin6, curthread))) { 900 tcp_over_udp_stop(); 901 return (ret); 902 } 903 #endif 904 return (0); 905 } 906 907 static int 908 sysctl_net_inet_tcp_udp_tunneling_port_check(SYSCTL_HANDLER_ARGS) 909 { 910 int error; 911 uint32_t old, new; 912 913 old = V_tcp_udp_tunneling_port; 914 new = old; 915 error = sysctl_handle_int(oidp, &new, 0, req); 916 if ((error == 0) && 917 (req->newptr != NULL)) { 918 if ((new < TCP_TUNNELING_PORT_MIN) || 919 (new > TCP_TUNNELING_PORT_MAX)) { 920 error = EINVAL; 921 } else { 922 sx_xlock(&tcpoudp_lock); 923 V_tcp_udp_tunneling_port = new; 924 if (old != 0) { 925 tcp_over_udp_stop(); 926 } 927 if (new != 0) { 928 error = tcp_over_udp_start(); 929 if (error != 0) { 930 V_tcp_udp_tunneling_port = 0; 931 } 932 } 933 sx_xunlock(&tcpoudp_lock); 934 } 935 } 936 return (error); 937 } 938 939 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, udp_tunneling_port, 940 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 941 &VNET_NAME(tcp_udp_tunneling_port), 942 0, &sysctl_net_inet_tcp_udp_tunneling_port_check, "IU", 943 "Tunneling port for tcp over udp"); 944 945 VNET_DEFINE(int, tcp_udp_tunneling_overhead) = TCP_TUNNELING_OVERHEAD_DEFAULT; 946 947 static int 948 sysctl_net_inet_tcp_udp_tunneling_overhead_check(SYSCTL_HANDLER_ARGS) 949 { 950 int error, new; 951 952 new = V_tcp_udp_tunneling_overhead; 953 error = sysctl_handle_int(oidp, &new, 0, req); 954 if (error == 0 && req->newptr) { 955 if ((new < TCP_TUNNELING_OVERHEAD_MIN) || 956 (new > TCP_TUNNELING_OVERHEAD_MAX)) 957 error = EINVAL; 958 else 959 V_tcp_udp_tunneling_overhead = new; 960 } 961 return (error); 962 } 963 964 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, udp_tunneling_overhead, 965 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 966 &VNET_NAME(tcp_udp_tunneling_overhead), 967 0, &sysctl_net_inet_tcp_udp_tunneling_overhead_check, "IU", 968 "MSS reduction when using tcp over udp"); 969 970 /* 971 * Exports one (struct tcp_function_info) for each alias/name. 972 */ 973 static int 974 sysctl_net_inet_list_func_info(SYSCTL_HANDLER_ARGS) 975 { 976 int cnt, error; 977 struct tcp_function *f; 978 struct tcp_function_info tfi; 979 980 /* 981 * We don't allow writes. 982 */ 983 if (req->newptr != NULL) 984 return (EINVAL); 985 986 /* 987 * Wire the old buffer so we can directly copy the functions to 988 * user space without dropping the lock. 989 */ 990 if (req->oldptr != NULL) { 991 error = sysctl_wire_old_buffer(req, 0); 992 if (error) 993 return (error); 994 } 995 996 /* 997 * Walk the list and copy out matching entries. If INVARIANTS 998 * is compiled in, also walk the list to verify the length of 999 * the list matches what we have recorded. 1000 */ 1001 rw_rlock(&tcp_function_lock); 1002 1003 cnt = 0; 1004 #ifndef INVARIANTS 1005 if (req->oldptr == NULL) { 1006 cnt = tcp_fb_cnt; 1007 goto skip_loop; 1008 } 1009 #endif 1010 TAILQ_FOREACH(f, &t_functions, tf_next) { 1011 #ifdef INVARIANTS 1012 cnt++; 1013 #endif 1014 if (req->oldptr != NULL) { 1015 bzero(&tfi, sizeof(tfi)); 1016 tfi.tfi_refcnt = f->tf_fb->tfb_refcnt; 1017 tfi.tfi_id = f->tf_fb->tfb_id; 1018 (void)strlcpy(tfi.tfi_alias, f->tf_name, 1019 sizeof(tfi.tfi_alias)); 1020 (void)strlcpy(tfi.tfi_name, 1021 f->tf_fb->tfb_tcp_block_name, sizeof(tfi.tfi_name)); 1022 error = SYSCTL_OUT(req, &tfi, sizeof(tfi)); 1023 /* 1024 * Don't stop on error, as that is the 1025 * mechanism we use to accumulate length 1026 * information if the buffer was too short. 1027 */ 1028 } 1029 } 1030 KASSERT(cnt == tcp_fb_cnt, 1031 ("%s: cnt (%d) != tcp_fb_cnt (%d)", __func__, cnt, tcp_fb_cnt)); 1032 #ifndef INVARIANTS 1033 skip_loop: 1034 #endif 1035 rw_runlock(&tcp_function_lock); 1036 if (req->oldptr == NULL) 1037 error = SYSCTL_OUT(req, NULL, 1038 (cnt + 1) * sizeof(struct tcp_function_info)); 1039 1040 return (error); 1041 } 1042 1043 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, function_info, 1044 CTLTYPE_OPAQUE | CTLFLAG_SKIP | CTLFLAG_RD | CTLFLAG_MPSAFE, 1045 NULL, 0, sysctl_net_inet_list_func_info, "S,tcp_function_info", 1046 "List TCP function block name-to-ID mappings"); 1047 1048 /* 1049 * tfb_tcp_handoff_ok() function for the default stack. 1050 * Note that we'll basically try to take all comers. 1051 */ 1052 static int 1053 tcp_default_handoff_ok(struct tcpcb *tp) 1054 { 1055 1056 return (0); 1057 } 1058 1059 /* 1060 * tfb_tcp_fb_init() function for the default stack. 1061 * 1062 * This handles making sure we have appropriate timers set if you are 1063 * transitioning a socket that has some amount of setup done. 1064 * 1065 * The init() fuction from the default can *never* return non-zero i.e. 1066 * it is required to always succeed since it is the stack of last resort! 1067 */ 1068 static int 1069 tcp_default_fb_init(struct tcpcb *tp, void **ptr) 1070 { 1071 struct socket *so = tptosocket(tp); 1072 int rexmt; 1073 1074 INP_WLOCK_ASSERT(tptoinpcb(tp)); 1075 /* We don't use the pointer */ 1076 *ptr = NULL; 1077 1078 KASSERT(tp->t_state >= 0 && tp->t_state < TCPS_TIME_WAIT, 1079 ("%s: connection %p in unexpected state %d", __func__, tp, 1080 tp->t_state)); 1081 1082 /* Make sure we get no interesting mbuf queuing behavior */ 1083 /* All mbuf queue/ack compress flags should be off */ 1084 tcp_lro_features_off(tp); 1085 1086 /* Cancel the GP measurement in progress */ 1087 tp->t_flags &= ~TF_GPUTINPROG; 1088 /* Validate the timers are not in usec, if they are convert */ 1089 tcp_change_time_units(tp, TCP_TMR_GRANULARITY_TICKS); 1090 if ((tp->t_state == TCPS_SYN_SENT) || 1091 (tp->t_state == TCPS_SYN_RECEIVED)) 1092 rexmt = tcp_rexmit_initial * tcp_backoff[tp->t_rxtshift]; 1093 else 1094 rexmt = TCP_REXMTVAL(tp) * tcp_backoff[tp->t_rxtshift]; 1095 if (tp->t_rxtshift == 0) 1096 tp->t_rxtcur = rexmt; 1097 else 1098 TCPT_RANGESET(tp->t_rxtcur, rexmt, tp->t_rttmin, TCPTV_REXMTMAX); 1099 1100 /* 1101 * Nothing to do for ESTABLISHED or LISTEN states. And, we don't 1102 * know what to do for unexpected states (which includes TIME_WAIT). 1103 */ 1104 if (tp->t_state <= TCPS_LISTEN || tp->t_state >= TCPS_TIME_WAIT) 1105 return (0); 1106 1107 /* 1108 * Make sure some kind of transmission timer is set if there is 1109 * outstanding data. 1110 */ 1111 if ((!TCPS_HAVEESTABLISHED(tp->t_state) || sbavail(&so->so_snd) || 1112 tp->snd_una != tp->snd_max) && !(tcp_timer_active(tp, TT_REXMT) || 1113 tcp_timer_active(tp, TT_PERSIST))) { 1114 /* 1115 * If the session has established and it looks like it should 1116 * be in the persist state, set the persist timer. Otherwise, 1117 * set the retransmit timer. 1118 */ 1119 if (TCPS_HAVEESTABLISHED(tp->t_state) && tp->snd_wnd == 0 && 1120 (int32_t)(tp->snd_nxt - tp->snd_una) < 1121 (int32_t)sbavail(&so->so_snd)) 1122 tcp_setpersist(tp); 1123 else 1124 tcp_timer_activate(tp, TT_REXMT, TP_RXTCUR(tp)); 1125 } 1126 1127 /* All non-embryonic sessions get a keepalive timer. */ 1128 if (!tcp_timer_active(tp, TT_KEEP)) 1129 tcp_timer_activate(tp, TT_KEEP, 1130 TCPS_HAVEESTABLISHED(tp->t_state) ? TP_KEEPIDLE(tp) : 1131 TP_KEEPINIT(tp)); 1132 1133 /* 1134 * Make sure critical variables are initialized 1135 * if transitioning while in Recovery. 1136 */ 1137 if IN_FASTRECOVERY(tp->t_flags) { 1138 if (tp->sackhint.recover_fs == 0) 1139 tp->sackhint.recover_fs = max(1, 1140 tp->snd_nxt - tp->snd_una); 1141 } 1142 1143 return (0); 1144 } 1145 1146 /* 1147 * tfb_tcp_fb_fini() function for the default stack. 1148 * 1149 * This changes state as necessary (or prudent) to prepare for another stack 1150 * to assume responsibility for the connection. 1151 */ 1152 static void 1153 tcp_default_fb_fini(struct tcpcb *tp, int tcb_is_purged) 1154 { 1155 1156 INP_WLOCK_ASSERT(tptoinpcb(tp)); 1157 1158 #ifdef TCP_BLACKBOX 1159 tcp_log_flowend(tp); 1160 #endif 1161 tp->t_acktime = 0; 1162 return; 1163 } 1164 1165 MALLOC_DEFINE(M_TCPLOG, "tcplog", "TCP address and flags print buffers"); 1166 MALLOC_DEFINE(M_TCPFUNCTIONS, "tcpfunc", "TCP function set memory"); 1167 1168 static struct mtx isn_mtx; 1169 1170 #define ISN_LOCK_INIT() mtx_init(&isn_mtx, "isn_mtx", NULL, MTX_DEF) 1171 #define ISN_LOCK() mtx_lock(&isn_mtx) 1172 #define ISN_UNLOCK() mtx_unlock(&isn_mtx) 1173 1174 INPCBSTORAGE_DEFINE(tcpcbstor, tcpcb, "tcpinp", "tcp_inpcb", "tcp", "tcphash"); 1175 1176 /* 1177 * Take a value and get the next power of 2 that doesn't overflow. 1178 * Used to size the tcp_inpcb hash buckets. 1179 */ 1180 static int 1181 maketcp_hashsize(int size) 1182 { 1183 int hashsize; 1184 1185 /* 1186 * auto tune. 1187 * get the next power of 2 higher than maxsockets. 1188 */ 1189 hashsize = 1 << fls(size); 1190 /* catch overflow, and just go one power of 2 smaller */ 1191 if (hashsize < size) { 1192 hashsize = 1 << (fls(size) - 1); 1193 } 1194 return (hashsize); 1195 } 1196 1197 static volatile int next_tcp_stack_id = 1; 1198 1199 /* 1200 * Register a TCP function block with the name provided in the names 1201 * array. (Note that this function does NOT automatically register 1202 * blk->tfb_tcp_block_name as a stack name. Therefore, you should 1203 * explicitly include blk->tfb_tcp_block_name in the list of names if 1204 * you wish to register the stack with that name.) 1205 * 1206 * Either all name registrations will succeed or all will fail. If 1207 * a name registration fails, the function will update the num_names 1208 * argument to point to the array index of the name that encountered 1209 * the failure. 1210 * 1211 * Returns 0 on success, or an error code on failure. 1212 */ 1213 int 1214 register_tcp_functions_as_names(struct tcp_function_block *blk, int wait, 1215 const char *names[], int *num_names) 1216 { 1217 struct tcp_function *n; 1218 struct tcp_function_set fs; 1219 int error, i; 1220 1221 KASSERT(names != NULL && *num_names > 0, 1222 ("%s: Called with 0-length name list", __func__)); 1223 KASSERT(names != NULL, ("%s: Called with NULL name list", __func__)); 1224 KASSERT(rw_initialized(&tcp_function_lock), 1225 ("%s: called too early", __func__)); 1226 1227 if ((blk->tfb_tcp_output == NULL) || 1228 (blk->tfb_tcp_do_segment == NULL) || 1229 (blk->tfb_tcp_ctloutput == NULL) || 1230 (strlen(blk->tfb_tcp_block_name) == 0)) { 1231 /* 1232 * These functions are required and you 1233 * need a name. 1234 */ 1235 *num_names = 0; 1236 return (EINVAL); 1237 } 1238 1239 if (blk->tfb_flags & TCP_FUNC_BEING_REMOVED) { 1240 *num_names = 0; 1241 return (EINVAL); 1242 } 1243 1244 refcount_init(&blk->tfb_refcnt, 0); 1245 blk->tfb_id = atomic_fetchadd_int(&next_tcp_stack_id, 1); 1246 for (i = 0; i < *num_names; i++) { 1247 n = malloc(sizeof(struct tcp_function), M_TCPFUNCTIONS, wait); 1248 if (n == NULL) { 1249 error = ENOMEM; 1250 goto cleanup; 1251 } 1252 n->tf_fb = blk; 1253 1254 (void)strlcpy(fs.function_set_name, names[i], 1255 sizeof(fs.function_set_name)); 1256 rw_wlock(&tcp_function_lock); 1257 if (find_tcp_functions_locked(&fs) != NULL) { 1258 /* Duplicate name space not allowed */ 1259 rw_wunlock(&tcp_function_lock); 1260 free(n, M_TCPFUNCTIONS); 1261 error = EALREADY; 1262 goto cleanup; 1263 } 1264 (void)strlcpy(n->tf_name, names[i], sizeof(n->tf_name)); 1265 TAILQ_INSERT_TAIL(&t_functions, n, tf_next); 1266 tcp_fb_cnt++; 1267 rw_wunlock(&tcp_function_lock); 1268 } 1269 return(0); 1270 1271 cleanup: 1272 /* 1273 * Deregister the names we just added. Because registration failed 1274 * for names[i], we don't need to deregister that name. 1275 */ 1276 *num_names = i; 1277 rw_wlock(&tcp_function_lock); 1278 while (--i >= 0) { 1279 TAILQ_FOREACH(n, &t_functions, tf_next) { 1280 if (!strncmp(n->tf_name, names[i], 1281 TCP_FUNCTION_NAME_LEN_MAX)) { 1282 TAILQ_REMOVE(&t_functions, n, tf_next); 1283 tcp_fb_cnt--; 1284 n->tf_fb = NULL; 1285 free(n, M_TCPFUNCTIONS); 1286 break; 1287 } 1288 } 1289 } 1290 rw_wunlock(&tcp_function_lock); 1291 return (error); 1292 } 1293 1294 /* 1295 * Register a TCP function block using the name provided in the name 1296 * argument. 1297 * 1298 * Returns 0 on success, or an error code on failure. 1299 */ 1300 int 1301 register_tcp_functions_as_name(struct tcp_function_block *blk, const char *name, 1302 int wait) 1303 { 1304 const char *name_list[1]; 1305 int num_names, rv; 1306 1307 num_names = 1; 1308 if (name != NULL) 1309 name_list[0] = name; 1310 else 1311 name_list[0] = blk->tfb_tcp_block_name; 1312 rv = register_tcp_functions_as_names(blk, wait, name_list, &num_names); 1313 return (rv); 1314 } 1315 1316 /* 1317 * Register a TCP function block using the name defined in 1318 * blk->tfb_tcp_block_name. 1319 * 1320 * Returns 0 on success, or an error code on failure. 1321 */ 1322 int 1323 register_tcp_functions(struct tcp_function_block *blk, int wait) 1324 { 1325 1326 return (register_tcp_functions_as_name(blk, NULL, wait)); 1327 } 1328 1329 /* 1330 * Deregister all names associated with a function block. This 1331 * functionally removes the function block from use within the system. 1332 * 1333 * When called with a true quiesce argument, mark the function block 1334 * as being removed so no more stacks will use it and determine 1335 * whether the removal would succeed. 1336 * 1337 * When called with a false quiesce argument, actually attempt the 1338 * removal. 1339 * 1340 * When called with a force argument, attempt to switch all TCBs to 1341 * use the default stack instead of returning EBUSY. 1342 * 1343 * Returns 0 on success (or if the removal would succeed), or an error 1344 * code on failure. 1345 */ 1346 int 1347 deregister_tcp_functions(struct tcp_function_block *blk, bool quiesce, 1348 bool force) 1349 { 1350 struct tcp_function *f; 1351 VNET_ITERATOR_DECL(vnet_iter); 1352 1353 if (blk == &tcp_def_funcblk) { 1354 /* You can't un-register the default */ 1355 return (EPERM); 1356 } 1357 rw_wlock(&tcp_function_lock); 1358 VNET_LIST_RLOCK_NOSLEEP(); 1359 VNET_FOREACH(vnet_iter) { 1360 CURVNET_SET(vnet_iter); 1361 if (blk == V_tcp_func_set_ptr) { 1362 /* You can't free the current default in some vnet. */ 1363 CURVNET_RESTORE(); 1364 VNET_LIST_RUNLOCK_NOSLEEP(); 1365 rw_wunlock(&tcp_function_lock); 1366 return (EBUSY); 1367 } 1368 CURVNET_RESTORE(); 1369 } 1370 VNET_LIST_RUNLOCK_NOSLEEP(); 1371 /* Mark the block so no more stacks can use it. */ 1372 blk->tfb_flags |= TCP_FUNC_BEING_REMOVED; 1373 /* 1374 * If TCBs are still attached to the stack, attempt to switch them 1375 * to the default stack. 1376 */ 1377 if (force && blk->tfb_refcnt) { 1378 struct inpcb *inp; 1379 struct tcpcb *tp; 1380 VNET_ITERATOR_DECL(vnet_iter); 1381 1382 rw_wunlock(&tcp_function_lock); 1383 1384 VNET_LIST_RLOCK(); 1385 VNET_FOREACH(vnet_iter) { 1386 CURVNET_SET(vnet_iter); 1387 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, 1388 INPLOOKUP_WLOCKPCB); 1389 1390 while ((inp = inp_next(&inpi)) != NULL) { 1391 tp = intotcpcb(inp); 1392 if (tp == NULL || tp->t_fb != blk) 1393 continue; 1394 tcp_switch_back_to_default(tp); 1395 } 1396 CURVNET_RESTORE(); 1397 } 1398 VNET_LIST_RUNLOCK(); 1399 1400 rw_wlock(&tcp_function_lock); 1401 } 1402 if (blk->tfb_refcnt) { 1403 /* TCBs still attached. */ 1404 rw_wunlock(&tcp_function_lock); 1405 return (EBUSY); 1406 } 1407 if (quiesce) { 1408 /* Skip removal. */ 1409 rw_wunlock(&tcp_function_lock); 1410 return (0); 1411 } 1412 /* Remove any function names that map to this function block. */ 1413 while (find_tcp_fb_locked(blk, &f) != NULL) { 1414 TAILQ_REMOVE(&t_functions, f, tf_next); 1415 tcp_fb_cnt--; 1416 f->tf_fb = NULL; 1417 free(f, M_TCPFUNCTIONS); 1418 } 1419 rw_wunlock(&tcp_function_lock); 1420 return (0); 1421 } 1422 1423 static void 1424 tcp_drain(void) 1425 { 1426 struct epoch_tracker et; 1427 VNET_ITERATOR_DECL(vnet_iter); 1428 1429 if (!do_tcpdrain) 1430 return; 1431 1432 NET_EPOCH_ENTER(et); 1433 VNET_LIST_RLOCK_NOSLEEP(); 1434 VNET_FOREACH(vnet_iter) { 1435 CURVNET_SET(vnet_iter); 1436 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, 1437 INPLOOKUP_WLOCKPCB); 1438 struct inpcb *inpb; 1439 struct tcpcb *tcpb; 1440 1441 /* 1442 * Walk the tcpbs, if existing, and flush the reassembly queue, 1443 * if there is one... 1444 * XXX: The "Net/3" implementation doesn't imply that the TCP 1445 * reassembly queue should be flushed, but in a situation 1446 * where we're really low on mbufs, this is potentially 1447 * useful. 1448 */ 1449 while ((inpb = inp_next(&inpi)) != NULL) { 1450 if ((tcpb = intotcpcb(inpb)) != NULL) { 1451 tcp_reass_flush(tcpb); 1452 tcp_clean_sackreport(tcpb); 1453 #ifdef TCP_BLACKBOX 1454 tcp_log_drain(tcpb); 1455 #endif 1456 #ifdef TCPPCAP 1457 if (tcp_pcap_aggressive_free) { 1458 /* Free the TCP PCAP queues. */ 1459 tcp_pcap_drain(&(tcpb->t_inpkts)); 1460 tcp_pcap_drain(&(tcpb->t_outpkts)); 1461 } 1462 #endif 1463 } 1464 } 1465 CURVNET_RESTORE(); 1466 } 1467 VNET_LIST_RUNLOCK_NOSLEEP(); 1468 NET_EPOCH_EXIT(et); 1469 } 1470 1471 static void 1472 tcp_vnet_init(void *arg __unused) 1473 { 1474 1475 #ifdef TCP_HHOOK 1476 if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN, 1477 &V_tcp_hhh[HHOOK_TCP_EST_IN], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0) 1478 printf("%s: WARNING: unable to register helper hook\n", __func__); 1479 if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT, 1480 &V_tcp_hhh[HHOOK_TCP_EST_OUT], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0) 1481 printf("%s: WARNING: unable to register helper hook\n", __func__); 1482 #endif 1483 #ifdef STATS 1484 if (tcp_stats_init()) 1485 printf("%s: WARNING: unable to initialise TCP stats\n", 1486 __func__); 1487 #endif 1488 in_pcbinfo_init(&V_tcbinfo, &tcpcbstor, tcp_tcbhashsize, 1489 tcp_tcbhashsize); 1490 1491 syncache_init(); 1492 tcp_hc_init(); 1493 1494 TUNABLE_INT_FETCH("net.inet.tcp.sack.enable", &V_tcp_do_sack); 1495 V_sack_hole_zone = uma_zcreate("sackhole", sizeof(struct sackhole), 1496 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 1497 1498 tcp_fastopen_init(); 1499 1500 COUNTER_ARRAY_ALLOC(V_tcps_states, TCP_NSTATES, M_WAITOK); 1501 VNET_PCPUSTAT_ALLOC(tcpstat, M_WAITOK); 1502 1503 V_tcp_msl = TCPTV_MSL; 1504 } 1505 VNET_SYSINIT(tcp_vnet_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, 1506 tcp_vnet_init, NULL); 1507 1508 static void 1509 tcp_init(void *arg __unused) 1510 { 1511 int hashsize; 1512 1513 tcp_reass_global_init(); 1514 1515 /* XXX virtualize those below? */ 1516 tcp_delacktime = TCPTV_DELACK; 1517 tcp_keepinit = TCPTV_KEEP_INIT; 1518 tcp_keepidle = TCPTV_KEEP_IDLE; 1519 tcp_keepintvl = TCPTV_KEEPINTVL; 1520 tcp_maxpersistidle = TCPTV_KEEP_IDLE; 1521 tcp_rexmit_initial = TCPTV_RTOBASE; 1522 if (tcp_rexmit_initial < 1) 1523 tcp_rexmit_initial = 1; 1524 tcp_rexmit_min = TCPTV_MIN; 1525 if (tcp_rexmit_min < 1) 1526 tcp_rexmit_min = 1; 1527 tcp_persmin = TCPTV_PERSMIN; 1528 tcp_persmax = TCPTV_PERSMAX; 1529 tcp_rexmit_slop = TCPTV_CPU_VAR; 1530 tcp_finwait2_timeout = TCPTV_FINWAIT2_TIMEOUT; 1531 1532 /* Setup the tcp function block list */ 1533 TAILQ_INIT(&t_functions); 1534 rw_init(&tcp_function_lock, "tcp_func_lock"); 1535 register_tcp_functions(&tcp_def_funcblk, M_WAITOK); 1536 sx_init(&tcpoudp_lock, "TCP over UDP configuration"); 1537 #ifdef TCP_BLACKBOX 1538 /* Initialize the TCP logging data. */ 1539 tcp_log_init(); 1540 #endif 1541 arc4rand(&V_ts_offset_secret, sizeof(V_ts_offset_secret), 0); 1542 1543 if (tcp_soreceive_stream) { 1544 #ifdef INET 1545 tcp_protosw.pr_soreceive = soreceive_stream; 1546 #endif 1547 #ifdef INET6 1548 tcp6_protosw.pr_soreceive = soreceive_stream; 1549 #endif /* INET6 */ 1550 } 1551 1552 #ifdef INET6 1553 max_protohdr_grow(sizeof(struct ip6_hdr) + sizeof(struct tcphdr)); 1554 #else /* INET6 */ 1555 max_protohdr_grow(sizeof(struct tcpiphdr)); 1556 #endif /* INET6 */ 1557 1558 ISN_LOCK_INIT(); 1559 EVENTHANDLER_REGISTER(shutdown_pre_sync, tcp_fini, NULL, 1560 SHUTDOWN_PRI_DEFAULT); 1561 EVENTHANDLER_REGISTER(vm_lowmem, tcp_drain, NULL, LOWMEM_PRI_DEFAULT); 1562 EVENTHANDLER_REGISTER(mbuf_lowmem, tcp_drain, NULL, LOWMEM_PRI_DEFAULT); 1563 1564 tcp_inp_lro_direct_queue = counter_u64_alloc(M_WAITOK); 1565 tcp_inp_lro_wokeup_queue = counter_u64_alloc(M_WAITOK); 1566 tcp_inp_lro_compressed = counter_u64_alloc(M_WAITOK); 1567 tcp_inp_lro_locks_taken = counter_u64_alloc(M_WAITOK); 1568 tcp_extra_mbuf = counter_u64_alloc(M_WAITOK); 1569 tcp_would_have_but = counter_u64_alloc(M_WAITOK); 1570 tcp_comp_total = counter_u64_alloc(M_WAITOK); 1571 tcp_uncomp_total = counter_u64_alloc(M_WAITOK); 1572 tcp_bad_csums = counter_u64_alloc(M_WAITOK); 1573 tcp_pacing_failures = counter_u64_alloc(M_WAITOK); 1574 #ifdef TCPPCAP 1575 tcp_pcap_init(); 1576 #endif 1577 1578 hashsize = tcp_tcbhashsize; 1579 if (hashsize == 0) { 1580 /* 1581 * Auto tune the hash size based on maxsockets. 1582 * A perfect hash would have a 1:1 mapping 1583 * (hashsize = maxsockets) however it's been 1584 * suggested that O(2) average is better. 1585 */ 1586 hashsize = maketcp_hashsize(maxsockets / 4); 1587 /* 1588 * Our historical default is 512, 1589 * do not autotune lower than this. 1590 */ 1591 if (hashsize < 512) 1592 hashsize = 512; 1593 if (bootverbose) 1594 printf("%s: %s auto tuned to %d\n", __func__, 1595 "net.inet.tcp.tcbhashsize", hashsize); 1596 } 1597 /* 1598 * We require a hashsize to be a power of two. 1599 * Previously if it was not a power of two we would just reset it 1600 * back to 512, which could be a nasty surprise if you did not notice 1601 * the error message. 1602 * Instead what we do is clip it to the closest power of two lower 1603 * than the specified hash value. 1604 */ 1605 if (!powerof2(hashsize)) { 1606 int oldhashsize = hashsize; 1607 1608 hashsize = maketcp_hashsize(hashsize); 1609 /* prevent absurdly low value */ 1610 if (hashsize < 16) 1611 hashsize = 16; 1612 printf("%s: WARNING: TCB hash size not a power of 2, " 1613 "clipped from %d to %d.\n", __func__, oldhashsize, 1614 hashsize); 1615 } 1616 tcp_tcbhashsize = hashsize; 1617 1618 #ifdef INET 1619 IPPROTO_REGISTER(IPPROTO_TCP, tcp_input, tcp_ctlinput); 1620 #endif 1621 #ifdef INET6 1622 IP6PROTO_REGISTER(IPPROTO_TCP, tcp6_input, tcp6_ctlinput); 1623 #endif 1624 } 1625 SYSINIT(tcp_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, tcp_init, NULL); 1626 1627 #ifdef VIMAGE 1628 static void 1629 tcp_destroy(void *unused __unused) 1630 { 1631 int n; 1632 #ifdef TCP_HHOOK 1633 int error; 1634 #endif 1635 1636 /* 1637 * All our processes are gone, all our sockets should be cleaned 1638 * up, which means, we should be past the tcp_discardcb() calls. 1639 * Sleep to let all tcpcb timers really disappear and cleanup. 1640 */ 1641 for (;;) { 1642 INP_INFO_WLOCK(&V_tcbinfo); 1643 n = V_tcbinfo.ipi_count; 1644 INP_INFO_WUNLOCK(&V_tcbinfo); 1645 if (n == 0) 1646 break; 1647 pause("tcpdes", hz / 10); 1648 } 1649 tcp_hc_destroy(); 1650 syncache_destroy(); 1651 in_pcbinfo_destroy(&V_tcbinfo); 1652 /* tcp_discardcb() clears the sack_holes up. */ 1653 uma_zdestroy(V_sack_hole_zone); 1654 1655 /* 1656 * Cannot free the zone until all tcpcbs are released as we attach 1657 * the allocations to them. 1658 */ 1659 tcp_fastopen_destroy(); 1660 1661 COUNTER_ARRAY_FREE(V_tcps_states, TCP_NSTATES); 1662 VNET_PCPUSTAT_FREE(tcpstat); 1663 1664 #ifdef TCP_HHOOK 1665 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_IN]); 1666 if (error != 0) { 1667 printf("%s: WARNING: unable to deregister helper hook " 1668 "type=%d, id=%d: error %d returned\n", __func__, 1669 HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN, error); 1670 } 1671 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_OUT]); 1672 if (error != 0) { 1673 printf("%s: WARNING: unable to deregister helper hook " 1674 "type=%d, id=%d: error %d returned\n", __func__, 1675 HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT, error); 1676 } 1677 #endif 1678 } 1679 VNET_SYSUNINIT(tcp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, tcp_destroy, NULL); 1680 #endif 1681 1682 void 1683 tcp_fini(void *xtp) 1684 { 1685 1686 } 1687 1688 /* 1689 * Fill in the IP and TCP headers for an outgoing packet, given the tcpcb. 1690 * tcp_template used to store this data in mbufs, but we now recopy it out 1691 * of the tcpcb each time to conserve mbufs. 1692 */ 1693 void 1694 tcpip_fillheaders(struct inpcb *inp, uint16_t port, void *ip_ptr, void *tcp_ptr) 1695 { 1696 struct tcphdr *th = (struct tcphdr *)tcp_ptr; 1697 1698 INP_WLOCK_ASSERT(inp); 1699 1700 #ifdef INET6 1701 if ((inp->inp_vflag & INP_IPV6) != 0) { 1702 struct ip6_hdr *ip6; 1703 1704 ip6 = (struct ip6_hdr *)ip_ptr; 1705 ip6->ip6_flow = (ip6->ip6_flow & ~IPV6_FLOWINFO_MASK) | 1706 (inp->inp_flow & IPV6_FLOWINFO_MASK); 1707 ip6->ip6_vfc = (ip6->ip6_vfc & ~IPV6_VERSION_MASK) | 1708 (IPV6_VERSION & IPV6_VERSION_MASK); 1709 if (port == 0) 1710 ip6->ip6_nxt = IPPROTO_TCP; 1711 else 1712 ip6->ip6_nxt = IPPROTO_UDP; 1713 ip6->ip6_plen = htons(sizeof(struct tcphdr)); 1714 ip6->ip6_src = inp->in6p_laddr; 1715 ip6->ip6_dst = inp->in6p_faddr; 1716 } 1717 #endif /* INET6 */ 1718 #if defined(INET6) && defined(INET) 1719 else 1720 #endif 1721 #ifdef INET 1722 { 1723 struct ip *ip; 1724 1725 ip = (struct ip *)ip_ptr; 1726 ip->ip_v = IPVERSION; 1727 ip->ip_hl = 5; 1728 ip->ip_tos = inp->inp_ip_tos; 1729 ip->ip_len = 0; 1730 ip->ip_id = 0; 1731 ip->ip_off = 0; 1732 ip->ip_ttl = inp->inp_ip_ttl; 1733 ip->ip_sum = 0; 1734 if (port == 0) 1735 ip->ip_p = IPPROTO_TCP; 1736 else 1737 ip->ip_p = IPPROTO_UDP; 1738 ip->ip_src = inp->inp_laddr; 1739 ip->ip_dst = inp->inp_faddr; 1740 } 1741 #endif /* INET */ 1742 th->th_sport = inp->inp_lport; 1743 th->th_dport = inp->inp_fport; 1744 th->th_seq = 0; 1745 th->th_ack = 0; 1746 th->th_off = 5; 1747 tcp_set_flags(th, 0); 1748 th->th_win = 0; 1749 th->th_urp = 0; 1750 th->th_sum = 0; /* in_pseudo() is called later for ipv4 */ 1751 } 1752 1753 /* 1754 * Create template to be used to send tcp packets on a connection. 1755 * Allocates an mbuf and fills in a skeletal tcp/ip header. The only 1756 * use for this function is in keepalives, which use tcp_respond. 1757 */ 1758 struct tcptemp * 1759 tcpip_maketemplate(struct inpcb *inp) 1760 { 1761 struct tcptemp *t; 1762 1763 t = malloc(sizeof(*t), M_TEMP, M_NOWAIT); 1764 if (t == NULL) 1765 return (NULL); 1766 tcpip_fillheaders(inp, 0, (void *)&t->tt_ipgen, (void *)&t->tt_t); 1767 return (t); 1768 } 1769 1770 /* 1771 * Send a single message to the TCP at address specified by 1772 * the given TCP/IP header. If m == NULL, then we make a copy 1773 * of the tcpiphdr at th and send directly to the addressed host. 1774 * This is used to force keep alive messages out using the TCP 1775 * template for a connection. If flags are given then we send 1776 * a message back to the TCP which originated the segment th, 1777 * and discard the mbuf containing it and any other attached mbufs. 1778 * 1779 * In any case the ack and sequence number of the transmitted 1780 * segment are as specified by the parameters. 1781 * 1782 * NOTE: If m != NULL, then th must point to *inside* the mbuf. 1783 */ 1784 void 1785 tcp_respond(struct tcpcb *tp, void *ipgen, struct tcphdr *th, struct mbuf *m, 1786 tcp_seq ack, tcp_seq seq, uint16_t flags) 1787 { 1788 struct tcpopt to; 1789 struct inpcb *inp; 1790 struct ip *ip; 1791 struct mbuf *optm; 1792 struct udphdr *uh = NULL; 1793 struct tcphdr *nth; 1794 struct tcp_log_buffer *lgb; 1795 u_char *optp; 1796 #ifdef INET6 1797 struct ip6_hdr *ip6; 1798 int isipv6; 1799 #endif /* INET6 */ 1800 int optlen, tlen, win, ulen; 1801 int ect = 0; 1802 bool incl_opts; 1803 uint16_t port; 1804 int output_ret; 1805 #ifdef INVARIANTS 1806 int thflags = tcp_get_flags(th); 1807 #endif 1808 1809 KASSERT(tp != NULL || m != NULL, ("tcp_respond: tp and m both NULL")); 1810 NET_EPOCH_ASSERT(); 1811 1812 #ifdef INET6 1813 isipv6 = ((struct ip *)ipgen)->ip_v == (IPV6_VERSION >> 4); 1814 ip6 = ipgen; 1815 #endif /* INET6 */ 1816 ip = ipgen; 1817 1818 if (tp != NULL) { 1819 inp = tptoinpcb(tp); 1820 INP_LOCK_ASSERT(inp); 1821 } else 1822 inp = NULL; 1823 1824 if (m != NULL) { 1825 #ifdef INET6 1826 if (isipv6 && ip6 && (ip6->ip6_nxt == IPPROTO_UDP)) 1827 port = m->m_pkthdr.tcp_tun_port; 1828 else 1829 #endif 1830 if (ip && (ip->ip_p == IPPROTO_UDP)) 1831 port = m->m_pkthdr.tcp_tun_port; 1832 else 1833 port = 0; 1834 } else 1835 port = tp->t_port; 1836 1837 incl_opts = false; 1838 win = 0; 1839 if (tp != NULL) { 1840 if (!(flags & TH_RST)) { 1841 win = sbspace(&inp->inp_socket->so_rcv); 1842 if (win > TCP_MAXWIN << tp->rcv_scale) 1843 win = TCP_MAXWIN << tp->rcv_scale; 1844 } 1845 if ((tp->t_flags & TF_NOOPT) == 0) 1846 incl_opts = true; 1847 } 1848 if (m == NULL) { 1849 m = m_gethdr(M_NOWAIT, MT_DATA); 1850 if (m == NULL) 1851 return; 1852 m->m_data += max_linkhdr; 1853 #ifdef INET6 1854 if (isipv6) { 1855 bcopy((caddr_t)ip6, mtod(m, caddr_t), 1856 sizeof(struct ip6_hdr)); 1857 ip6 = mtod(m, struct ip6_hdr *); 1858 nth = (struct tcphdr *)(ip6 + 1); 1859 if (port) { 1860 /* Insert a UDP header */ 1861 uh = (struct udphdr *)nth; 1862 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1863 uh->uh_dport = port; 1864 nth = (struct tcphdr *)(uh + 1); 1865 } 1866 } else 1867 #endif /* INET6 */ 1868 { 1869 bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip)); 1870 ip = mtod(m, struct ip *); 1871 nth = (struct tcphdr *)(ip + 1); 1872 if (port) { 1873 /* Insert a UDP header */ 1874 uh = (struct udphdr *)nth; 1875 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1876 uh->uh_dport = port; 1877 nth = (struct tcphdr *)(uh + 1); 1878 } 1879 } 1880 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr)); 1881 flags = TH_ACK; 1882 } else if ((!M_WRITABLE(m)) || (port != 0)) { 1883 struct mbuf *n; 1884 1885 /* Can't reuse 'm', allocate a new mbuf. */ 1886 n = m_gethdr(M_NOWAIT, MT_DATA); 1887 if (n == NULL) { 1888 m_freem(m); 1889 return; 1890 } 1891 1892 if (!m_dup_pkthdr(n, m, M_NOWAIT)) { 1893 m_freem(m); 1894 m_freem(n); 1895 return; 1896 } 1897 1898 n->m_data += max_linkhdr; 1899 /* m_len is set later */ 1900 #define xchg(a,b,type) { type t; t=a; a=b; b=t; } 1901 #ifdef INET6 1902 if (isipv6) { 1903 bcopy((caddr_t)ip6, mtod(n, caddr_t), 1904 sizeof(struct ip6_hdr)); 1905 ip6 = mtod(n, struct ip6_hdr *); 1906 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); 1907 nth = (struct tcphdr *)(ip6 + 1); 1908 if (port) { 1909 /* Insert a UDP header */ 1910 uh = (struct udphdr *)nth; 1911 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1912 uh->uh_dport = port; 1913 nth = (struct tcphdr *)(uh + 1); 1914 } 1915 } else 1916 #endif /* INET6 */ 1917 { 1918 bcopy((caddr_t)ip, mtod(n, caddr_t), sizeof(struct ip)); 1919 ip = mtod(n, struct ip *); 1920 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t); 1921 nth = (struct tcphdr *)(ip + 1); 1922 if (port) { 1923 /* Insert a UDP header */ 1924 uh = (struct udphdr *)nth; 1925 uh->uh_sport = htons(V_tcp_udp_tunneling_port); 1926 uh->uh_dport = port; 1927 nth = (struct tcphdr *)(uh + 1); 1928 } 1929 } 1930 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr)); 1931 xchg(nth->th_dport, nth->th_sport, uint16_t); 1932 th = nth; 1933 m_freem(m); 1934 m = n; 1935 } else { 1936 /* 1937 * reuse the mbuf. 1938 * XXX MRT We inherit the FIB, which is lucky. 1939 */ 1940 m_freem(m->m_next); 1941 m->m_next = NULL; 1942 m->m_data = (caddr_t)ipgen; 1943 /* clear any receive flags for proper bpf timestamping */ 1944 m->m_flags &= ~(M_TSTMP | M_TSTMP_LRO); 1945 /* m_len is set later */ 1946 #ifdef INET6 1947 if (isipv6) { 1948 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); 1949 nth = (struct tcphdr *)(ip6 + 1); 1950 } else 1951 #endif /* INET6 */ 1952 { 1953 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t); 1954 nth = (struct tcphdr *)(ip + 1); 1955 } 1956 if (th != nth) { 1957 /* 1958 * this is usually a case when an extension header 1959 * exists between the IPv6 header and the 1960 * TCP header. 1961 */ 1962 nth->th_sport = th->th_sport; 1963 nth->th_dport = th->th_dport; 1964 } 1965 xchg(nth->th_dport, nth->th_sport, uint16_t); 1966 #undef xchg 1967 } 1968 tlen = 0; 1969 #ifdef INET6 1970 if (isipv6) 1971 tlen = sizeof (struct ip6_hdr) + sizeof (struct tcphdr); 1972 #endif 1973 #if defined(INET) && defined(INET6) 1974 else 1975 #endif 1976 #ifdef INET 1977 tlen = sizeof (struct tcpiphdr); 1978 #endif 1979 if (port) 1980 tlen += sizeof (struct udphdr); 1981 #ifdef INVARIANTS 1982 m->m_len = 0; 1983 KASSERT(M_TRAILINGSPACE(m) >= tlen, 1984 ("Not enough trailing space for message (m=%p, need=%d, have=%ld)", 1985 m, tlen, (long)M_TRAILINGSPACE(m))); 1986 #endif 1987 m->m_len = tlen; 1988 to.to_flags = 0; 1989 if (incl_opts) { 1990 ect = tcp_ecn_output_established(tp, &flags, 0, false); 1991 /* Make sure we have room. */ 1992 if (M_TRAILINGSPACE(m) < TCP_MAXOLEN) { 1993 m->m_next = m_get(M_NOWAIT, MT_DATA); 1994 if (m->m_next) { 1995 optp = mtod(m->m_next, u_char *); 1996 optm = m->m_next; 1997 } else 1998 incl_opts = false; 1999 } else { 2000 optp = (u_char *) (nth + 1); 2001 optm = m; 2002 } 2003 } 2004 if (incl_opts) { 2005 /* Timestamps. */ 2006 if (tp->t_flags & TF_RCVD_TSTMP) { 2007 to.to_tsval = tcp_ts_getticks() + tp->ts_offset; 2008 to.to_tsecr = tp->ts_recent; 2009 to.to_flags |= TOF_TS; 2010 } 2011 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 2012 /* TCP-MD5 (RFC2385). */ 2013 if (tp->t_flags & TF_SIGNATURE) 2014 to.to_flags |= TOF_SIGNATURE; 2015 #endif 2016 /* Add the options. */ 2017 tlen += optlen = tcp_addoptions(&to, optp); 2018 2019 /* Update m_len in the correct mbuf. */ 2020 optm->m_len += optlen; 2021 } else 2022 optlen = 0; 2023 #ifdef INET6 2024 if (isipv6) { 2025 if (uh) { 2026 ulen = tlen - sizeof(struct ip6_hdr); 2027 uh->uh_ulen = htons(ulen); 2028 } 2029 ip6->ip6_flow = htonl(ect << IPV6_FLOWLABEL_LEN); 2030 ip6->ip6_vfc = IPV6_VERSION; 2031 if (port) 2032 ip6->ip6_nxt = IPPROTO_UDP; 2033 else 2034 ip6->ip6_nxt = IPPROTO_TCP; 2035 ip6->ip6_plen = htons(tlen - sizeof(*ip6)); 2036 } 2037 #endif 2038 #if defined(INET) && defined(INET6) 2039 else 2040 #endif 2041 #ifdef INET 2042 { 2043 if (uh) { 2044 ulen = tlen - sizeof(struct ip); 2045 uh->uh_ulen = htons(ulen); 2046 } 2047 ip->ip_len = htons(tlen); 2048 if (inp != NULL) { 2049 ip->ip_tos = inp->inp_ip_tos & ~IPTOS_ECN_MASK; 2050 ip->ip_ttl = inp->inp_ip_ttl; 2051 } else { 2052 ip->ip_tos = 0; 2053 ip->ip_ttl = V_ip_defttl; 2054 } 2055 ip->ip_tos |= ect; 2056 if (port) { 2057 ip->ip_p = IPPROTO_UDP; 2058 } else { 2059 ip->ip_p = IPPROTO_TCP; 2060 } 2061 if (V_path_mtu_discovery) 2062 ip->ip_off |= htons(IP_DF); 2063 } 2064 #endif 2065 m->m_pkthdr.len = tlen; 2066 m->m_pkthdr.rcvif = NULL; 2067 #ifdef MAC 2068 if (inp != NULL) { 2069 /* 2070 * Packet is associated with a socket, so allow the 2071 * label of the response to reflect the socket label. 2072 */ 2073 INP_LOCK_ASSERT(inp); 2074 mac_inpcb_create_mbuf(inp, m); 2075 } else { 2076 /* 2077 * Packet is not associated with a socket, so possibly 2078 * update the label in place. 2079 */ 2080 mac_netinet_tcp_reply(m); 2081 } 2082 #endif 2083 nth->th_seq = htonl(seq); 2084 nth->th_ack = htonl(ack); 2085 nth->th_off = (sizeof (struct tcphdr) + optlen) >> 2; 2086 tcp_set_flags(nth, flags); 2087 if (tp && (flags & TH_RST)) { 2088 /* Log the reset */ 2089 tcp_log_end_status(tp, TCP_EI_STATUS_SERVER_RST); 2090 } 2091 if (tp != NULL) 2092 nth->th_win = htons((u_short) (win >> tp->rcv_scale)); 2093 else 2094 nth->th_win = htons((u_short)win); 2095 nth->th_urp = 0; 2096 2097 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 2098 if (to.to_flags & TOF_SIGNATURE) { 2099 if (!TCPMD5_ENABLED() || 2100 TCPMD5_OUTPUT(m, nth, to.to_signature) != 0) { 2101 m_freem(m); 2102 return; 2103 } 2104 } 2105 #endif 2106 2107 #ifdef INET6 2108 if (isipv6) { 2109 if (port) { 2110 m->m_pkthdr.csum_flags = CSUM_UDP_IPV6; 2111 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 2112 uh->uh_sum = in6_cksum_pseudo(ip6, ulen, IPPROTO_UDP, 0); 2113 nth->th_sum = 0; 2114 } else { 2115 m->m_pkthdr.csum_flags = CSUM_TCP_IPV6; 2116 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); 2117 nth->th_sum = in6_cksum_pseudo(ip6, 2118 tlen - sizeof(struct ip6_hdr), IPPROTO_TCP, 0); 2119 } 2120 ip6->ip6_hlim = in6_selecthlim(inp, NULL); 2121 } 2122 #endif /* INET6 */ 2123 #if defined(INET6) && defined(INET) 2124 else 2125 #endif 2126 #ifdef INET 2127 { 2128 if (port) { 2129 uh->uh_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, 2130 htons(ulen + IPPROTO_UDP)); 2131 m->m_pkthdr.csum_flags = CSUM_UDP; 2132 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 2133 nth->th_sum = 0; 2134 } else { 2135 m->m_pkthdr.csum_flags = CSUM_TCP; 2136 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); 2137 nth->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, 2138 htons((u_short)(tlen - sizeof(struct ip) + ip->ip_p))); 2139 } 2140 } 2141 #endif /* INET */ 2142 TCP_PROBE3(debug__output, tp, th, m); 2143 if (flags & TH_RST) 2144 TCP_PROBE5(accept__refused, NULL, NULL, m, tp, nth); 2145 lgb = NULL; 2146 if ((tp != NULL) && tcp_bblogging_on(tp)) { 2147 if (INP_WLOCKED(inp)) { 2148 union tcp_log_stackspecific log; 2149 struct timeval tv; 2150 2151 memset(&log.u_bbr, 0, sizeof(log.u_bbr)); 2152 log.u_bbr.inhpts = tcp_in_hpts(tp); 2153 log.u_bbr.flex8 = 4; 2154 log.u_bbr.pkts_out = tp->t_maxseg; 2155 log.u_bbr.timeStamp = tcp_get_usecs(&tv); 2156 log.u_bbr.delivered = 0; 2157 lgb = tcp_log_event(tp, nth, NULL, NULL, TCP_LOG_OUT, 2158 ERRNO_UNK, 0, &log, false, NULL, NULL, 0, &tv); 2159 } else { 2160 /* 2161 * We can not log the packet, since we only own the 2162 * read lock, but a write lock is needed. The read lock 2163 * is not upgraded to a write lock, since only getting 2164 * the read lock was done intentionally to improve the 2165 * handling of SYN flooding attacks. 2166 * This happens only for pure SYN segments received in 2167 * the initial CLOSED state, or received in a more 2168 * advanced state than listen and the UDP encapsulation 2169 * port is unexpected. 2170 * The incoming SYN segments do not really belong to 2171 * the TCP connection and the handling does not change 2172 * the state of the TCP connection. Therefore, the 2173 * sending of the RST segments is not logged. Please 2174 * note that also the incoming SYN segments are not 2175 * logged. 2176 * 2177 * The following code ensures that the above description 2178 * is and stays correct. 2179 */ 2180 KASSERT((thflags & (TH_ACK|TH_SYN)) == TH_SYN && 2181 (tp->t_state == TCPS_CLOSED || 2182 (tp->t_state > TCPS_LISTEN && tp->t_port != port)), 2183 ("%s: Logging of TCP segment with flags 0x%b and " 2184 "UDP encapsulation port %u skipped in state %s", 2185 __func__, thflags, PRINT_TH_FLAGS, 2186 ntohs(port), tcpstates[tp->t_state])); 2187 } 2188 } 2189 2190 if (flags & TH_ACK) 2191 TCPSTAT_INC(tcps_sndacks); 2192 else if (flags & (TH_SYN|TH_FIN|TH_RST)) 2193 TCPSTAT_INC(tcps_sndctrl); 2194 TCPSTAT_INC(tcps_sndtotal); 2195 2196 #ifdef INET6 2197 if (isipv6) { 2198 TCP_PROBE5(send, NULL, tp, ip6, tp, nth); 2199 output_ret = ip6_output(m, inp ? inp->in6p_outputopts : NULL, 2200 NULL, 0, NULL, NULL, inp); 2201 } 2202 #endif /* INET6 */ 2203 #if defined(INET) && defined(INET6) 2204 else 2205 #endif 2206 #ifdef INET 2207 { 2208 TCP_PROBE5(send, NULL, tp, ip, tp, nth); 2209 output_ret = ip_output(m, NULL, NULL, 0, NULL, inp); 2210 } 2211 #endif 2212 if (lgb != NULL) 2213 lgb->tlb_errno = output_ret; 2214 } 2215 2216 /* 2217 * Create a new TCP control block, making an empty reassembly queue and hooking 2218 * it to the argument protocol control block. The `inp' parameter must have 2219 * come from the zone allocator set up by tcpcbstor declaration. 2220 */ 2221 struct tcpcb * 2222 tcp_newtcpcb(struct inpcb *inp) 2223 { 2224 struct tcpcb *tp = intotcpcb(inp); 2225 #ifdef INET6 2226 int isipv6 = (inp->inp_vflag & INP_IPV6) != 0; 2227 #endif /* INET6 */ 2228 2229 /* 2230 * Historically allocation was done with M_ZERO. There is a lot of 2231 * code that rely on that. For now take safe approach and zero whole 2232 * tcpcb. This definitely can be optimized. 2233 */ 2234 bzero(&tp->t_start_zero, t_zero_size); 2235 2236 /* Initialise cc_var struct for this tcpcb. */ 2237 tp->t_ccv.type = IPPROTO_TCP; 2238 tp->t_ccv.ccvc.tcp = tp; 2239 rw_rlock(&tcp_function_lock); 2240 tp->t_fb = V_tcp_func_set_ptr; 2241 refcount_acquire(&tp->t_fb->tfb_refcnt); 2242 rw_runlock(&tcp_function_lock); 2243 /* 2244 * Use the current system default CC algorithm. 2245 */ 2246 cc_attach(tp, CC_DEFAULT_ALGO()); 2247 2248 if (CC_ALGO(tp)->cb_init != NULL) 2249 if (CC_ALGO(tp)->cb_init(&tp->t_ccv, NULL) > 0) { 2250 cc_detach(tp); 2251 if (tp->t_fb->tfb_tcp_fb_fini) 2252 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); 2253 refcount_release(&tp->t_fb->tfb_refcnt); 2254 return (NULL); 2255 } 2256 2257 #ifdef TCP_HHOOK 2258 if (khelp_init_osd(HELPER_CLASS_TCP, &tp->t_osd)) { 2259 if (tp->t_fb->tfb_tcp_fb_fini) 2260 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); 2261 refcount_release(&tp->t_fb->tfb_refcnt); 2262 return (NULL); 2263 } 2264 #endif 2265 2266 TAILQ_INIT(&tp->t_segq); 2267 STAILQ_INIT(&tp->t_inqueue); 2268 tp->t_maxseg = 2269 #ifdef INET6 2270 isipv6 ? V_tcp_v6mssdflt : 2271 #endif /* INET6 */ 2272 V_tcp_mssdflt; 2273 2274 /* All mbuf queue/ack compress flags should be off */ 2275 tcp_lro_features_off(tp); 2276 2277 tp->t_hpts_cpu = HPTS_CPU_NONE; 2278 tp->t_lro_cpu = HPTS_CPU_NONE; 2279 2280 callout_init_rw(&tp->t_callout, &inp->inp_lock, CALLOUT_RETURNUNLOCKED); 2281 for (int i = 0; i < TT_N; i++) 2282 tp->t_timers[i] = SBT_MAX; 2283 2284 switch (V_tcp_do_rfc1323) { 2285 case 0: 2286 break; 2287 default: 2288 case 1: 2289 tp->t_flags = (TF_REQ_SCALE|TF_REQ_TSTMP); 2290 break; 2291 case 2: 2292 tp->t_flags = TF_REQ_SCALE; 2293 break; 2294 case 3: 2295 tp->t_flags = TF_REQ_TSTMP; 2296 break; 2297 } 2298 if (V_tcp_do_sack) 2299 tp->t_flags |= TF_SACK_PERMIT; 2300 TAILQ_INIT(&tp->snd_holes); 2301 2302 /* 2303 * Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no 2304 * rtt estimate. Set rttvar so that srtt + 4 * rttvar gives 2305 * reasonable initial retransmit time. 2306 */ 2307 tp->t_srtt = TCPTV_SRTTBASE; 2308 tp->t_rttvar = ((tcp_rexmit_initial - TCPTV_SRTTBASE) << TCP_RTTVAR_SHIFT) / 4; 2309 tp->t_rttmin = tcp_rexmit_min; 2310 tp->t_rxtcur = tcp_rexmit_initial; 2311 tp->snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT; 2312 tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT; 2313 tp->t_rcvtime = ticks; 2314 /* We always start with ticks granularity */ 2315 tp->t_tmr_granularity = TCP_TMR_GRANULARITY_TICKS; 2316 /* 2317 * IPv4 TTL initialization is necessary for an IPv6 socket as well, 2318 * because the socket may be bound to an IPv6 wildcard address, 2319 * which may match an IPv4-mapped IPv6 address. 2320 */ 2321 inp->inp_ip_ttl = V_ip_defttl; 2322 #ifdef TCPPCAP 2323 /* 2324 * Init the TCP PCAP queues. 2325 */ 2326 tcp_pcap_tcpcb_init(tp); 2327 #endif 2328 #ifdef TCP_BLACKBOX 2329 /* Initialize the per-TCPCB log data. */ 2330 tcp_log_tcpcbinit(tp); 2331 #endif 2332 tp->t_pacing_rate = -1; 2333 if (tp->t_fb->tfb_tcp_fb_init) { 2334 if ((*tp->t_fb->tfb_tcp_fb_init)(tp, &tp->t_fb_ptr)) { 2335 refcount_release(&tp->t_fb->tfb_refcnt); 2336 return (NULL); 2337 } 2338 } 2339 #ifdef STATS 2340 if (V_tcp_perconn_stats_enable == 1) 2341 tp->t_stats = stats_blob_alloc(V_tcp_perconn_stats_dflt_tpl, 0); 2342 #endif 2343 if (V_tcp_do_lrd) 2344 tp->t_flags |= TF_LRD; 2345 2346 return (tp); 2347 } 2348 2349 /* 2350 * Drop a TCP connection, reporting 2351 * the specified error. If connection is synchronized, 2352 * then send a RST to peer. 2353 */ 2354 struct tcpcb * 2355 tcp_drop(struct tcpcb *tp, int errno) 2356 { 2357 struct socket *so = tptosocket(tp); 2358 2359 NET_EPOCH_ASSERT(); 2360 INP_WLOCK_ASSERT(tptoinpcb(tp)); 2361 2362 if (TCPS_HAVERCVDSYN(tp->t_state)) { 2363 tcp_state_change(tp, TCPS_CLOSED); 2364 /* Don't use tcp_output() here due to possible recursion. */ 2365 (void)tcp_output_nodrop(tp); 2366 TCPSTAT_INC(tcps_drops); 2367 } else 2368 TCPSTAT_INC(tcps_conndrops); 2369 if (errno == ETIMEDOUT && tp->t_softerror) 2370 errno = tp->t_softerror; 2371 so->so_error = errno; 2372 return (tcp_close(tp)); 2373 } 2374 2375 void 2376 tcp_discardcb(struct tcpcb *tp) 2377 { 2378 struct inpcb *inp = tptoinpcb(tp); 2379 struct socket *so = tptosocket(tp); 2380 struct mbuf *m; 2381 #ifdef INET6 2382 bool isipv6 = (inp->inp_vflag & INP_IPV6) != 0; 2383 #endif 2384 2385 INP_WLOCK_ASSERT(inp); 2386 MPASS(!callout_active(&tp->t_callout)); 2387 MPASS(TAILQ_EMPTY(&tp->snd_holes)); 2388 2389 /* free the reassembly queue, if any */ 2390 tcp_reass_flush(tp); 2391 2392 #ifdef TCP_OFFLOAD 2393 /* Disconnect offload device, if any. */ 2394 if (tp->t_flags & TF_TOE) 2395 tcp_offload_detach(tp); 2396 #endif 2397 #ifdef TCPPCAP 2398 /* Free the TCP PCAP queues. */ 2399 tcp_pcap_drain(&(tp->t_inpkts)); 2400 tcp_pcap_drain(&(tp->t_outpkts)); 2401 #endif 2402 2403 /* Allow the CC algorithm to clean up after itself. */ 2404 if (CC_ALGO(tp)->cb_destroy != NULL) 2405 CC_ALGO(tp)->cb_destroy(&tp->t_ccv); 2406 CC_DATA(tp) = NULL; 2407 /* Detach from the CC algorithm */ 2408 cc_detach(tp); 2409 2410 #ifdef TCP_HHOOK 2411 khelp_destroy_osd(&tp->t_osd); 2412 #endif 2413 #ifdef STATS 2414 stats_blob_destroy(tp->t_stats); 2415 #endif 2416 2417 CC_ALGO(tp) = NULL; 2418 if ((m = STAILQ_FIRST(&tp->t_inqueue)) != NULL) { 2419 struct mbuf *prev; 2420 2421 STAILQ_INIT(&tp->t_inqueue); 2422 STAILQ_FOREACH_FROM_SAFE(m, &tp->t_inqueue, m_stailqpkt, prev) 2423 m_freem(m); 2424 } 2425 TCPSTATES_DEC(tp->t_state); 2426 2427 if (tp->t_fb->tfb_tcp_fb_fini) 2428 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1); 2429 MPASS(!tcp_in_hpts(tp)); 2430 #ifdef TCP_BLACKBOX 2431 tcp_log_tcpcbfini(tp); 2432 #endif 2433 2434 /* 2435 * If we got enough samples through the srtt filter, 2436 * save the rtt and rttvar in the routing entry. 2437 * 'Enough' is arbitrarily defined as 4 rtt samples. 2438 * 4 samples is enough for the srtt filter to converge 2439 * to within enough % of the correct value; fewer samples 2440 * and we could save a bogus rtt. The danger is not high 2441 * as tcp quickly recovers from everything. 2442 * XXX: Works very well but needs some more statistics! 2443 * 2444 * XXXRRS: Updating must be after the stack fini() since 2445 * that may be converting some internal representation of 2446 * say srtt etc into the general one used by other stacks. 2447 * Lets also at least protect against the so being NULL 2448 * as RW stated below. 2449 */ 2450 if ((tp->t_rttupdated >= 4) && (so != NULL)) { 2451 struct hc_metrics_lite metrics; 2452 uint32_t ssthresh; 2453 2454 bzero(&metrics, sizeof(metrics)); 2455 /* 2456 * Update the ssthresh always when the conditions below 2457 * are satisfied. This gives us better new start value 2458 * for the congestion avoidance for new connections. 2459 * ssthresh is only set if packet loss occurred on a session. 2460 * 2461 * XXXRW: 'so' may be NULL here, and/or socket buffer may be 2462 * being torn down. Ideally this code would not use 'so'. 2463 */ 2464 ssthresh = tp->snd_ssthresh; 2465 if (ssthresh != 0 && ssthresh < so->so_snd.sb_hiwat / 2) { 2466 /* 2467 * convert the limit from user data bytes to 2468 * packets then to packet data bytes. 2469 */ 2470 ssthresh = (ssthresh + tp->t_maxseg / 2) / tp->t_maxseg; 2471 if (ssthresh < 2) 2472 ssthresh = 2; 2473 ssthresh *= (tp->t_maxseg + 2474 #ifdef INET6 2475 (isipv6 ? sizeof (struct ip6_hdr) + 2476 sizeof (struct tcphdr) : 2477 #endif 2478 sizeof (struct tcpiphdr) 2479 #ifdef INET6 2480 ) 2481 #endif 2482 ); 2483 } else 2484 ssthresh = 0; 2485 metrics.rmx_ssthresh = ssthresh; 2486 2487 metrics.rmx_rtt = tp->t_srtt; 2488 metrics.rmx_rttvar = tp->t_rttvar; 2489 metrics.rmx_cwnd = tp->snd_cwnd; 2490 metrics.rmx_sendpipe = 0; 2491 metrics.rmx_recvpipe = 0; 2492 2493 tcp_hc_update(&inp->inp_inc, &metrics); 2494 } 2495 2496 refcount_release(&tp->t_fb->tfb_refcnt); 2497 } 2498 2499 /* 2500 * Attempt to close a TCP control block, marking it as dropped, and freeing 2501 * the socket if we hold the only reference. 2502 */ 2503 struct tcpcb * 2504 tcp_close(struct tcpcb *tp) 2505 { 2506 struct inpcb *inp = tptoinpcb(tp); 2507 struct socket *so = tptosocket(tp); 2508 2509 INP_WLOCK_ASSERT(inp); 2510 2511 #ifdef TCP_OFFLOAD 2512 if (tp->t_state == TCPS_LISTEN) 2513 tcp_offload_listen_stop(tp); 2514 #endif 2515 /* 2516 * This releases the TFO pending counter resource for TFO listen 2517 * sockets as well as passively-created TFO sockets that transition 2518 * from SYN_RECEIVED to CLOSED. 2519 */ 2520 if (tp->t_tfo_pending) { 2521 tcp_fastopen_decrement_counter(tp->t_tfo_pending); 2522 tp->t_tfo_pending = NULL; 2523 } 2524 tcp_timer_stop(tp); 2525 if (tp->t_fb->tfb_tcp_timer_stop_all != NULL) 2526 tp->t_fb->tfb_tcp_timer_stop_all(tp); 2527 in_pcbdrop(inp); 2528 TCPSTAT_INC(tcps_closed); 2529 if (tp->t_state != TCPS_CLOSED) 2530 tcp_state_change(tp, TCPS_CLOSED); 2531 KASSERT(inp->inp_socket != NULL, ("tcp_close: inp_socket NULL")); 2532 tcp_free_sackholes(tp); 2533 soisdisconnected(so); 2534 if (inp->inp_flags & INP_SOCKREF) { 2535 inp->inp_flags &= ~INP_SOCKREF; 2536 INP_WUNLOCK(inp); 2537 sorele(so); 2538 return (NULL); 2539 } 2540 return (tp); 2541 } 2542 2543 /* 2544 * Notify a tcp user of an asynchronous error; 2545 * store error as soft error, but wake up user 2546 * (for now, won't do anything until can select for soft error). 2547 * 2548 * Do not wake up user since there currently is no mechanism for 2549 * reporting soft errors (yet - a kqueue filter may be added). 2550 */ 2551 static struct inpcb * 2552 tcp_notify(struct inpcb *inp, int error) 2553 { 2554 struct tcpcb *tp; 2555 2556 INP_WLOCK_ASSERT(inp); 2557 2558 tp = intotcpcb(inp); 2559 KASSERT(tp != NULL, ("tcp_notify: tp == NULL")); 2560 2561 /* 2562 * Ignore some errors if we are hooked up. 2563 * If connection hasn't completed, has retransmitted several times, 2564 * and receives a second error, give up now. This is better 2565 * than waiting a long time to establish a connection that 2566 * can never complete. 2567 */ 2568 if (tp->t_state == TCPS_ESTABLISHED && 2569 (error == EHOSTUNREACH || error == ENETUNREACH || 2570 error == EHOSTDOWN)) { 2571 if (inp->inp_route.ro_nh) { 2572 NH_FREE(inp->inp_route.ro_nh); 2573 inp->inp_route.ro_nh = (struct nhop_object *)NULL; 2574 } 2575 return (inp); 2576 } else if (tp->t_state < TCPS_ESTABLISHED && tp->t_rxtshift > 3 && 2577 tp->t_softerror) { 2578 tp = tcp_drop(tp, error); 2579 if (tp != NULL) 2580 return (inp); 2581 else 2582 return (NULL); 2583 } else { 2584 tp->t_softerror = error; 2585 return (inp); 2586 } 2587 #if 0 2588 wakeup( &so->so_timeo); 2589 sorwakeup(so); 2590 sowwakeup(so); 2591 #endif 2592 } 2593 2594 static int 2595 tcp_pcblist(SYSCTL_HANDLER_ARGS) 2596 { 2597 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo, 2598 INPLOOKUP_RLOCKPCB); 2599 struct xinpgen xig; 2600 struct inpcb *inp; 2601 int error; 2602 2603 if (req->newptr != NULL) 2604 return (EPERM); 2605 2606 if (req->oldptr == NULL) { 2607 int n; 2608 2609 n = V_tcbinfo.ipi_count + 2610 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); 2611 n += imax(n / 8, 10); 2612 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xtcpcb); 2613 return (0); 2614 } 2615 2616 if ((error = sysctl_wire_old_buffer(req, 0)) != 0) 2617 return (error); 2618 2619 bzero(&xig, sizeof(xig)); 2620 xig.xig_len = sizeof xig; 2621 xig.xig_count = V_tcbinfo.ipi_count + 2622 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); 2623 xig.xig_gen = V_tcbinfo.ipi_gencnt; 2624 xig.xig_sogen = so_gencnt; 2625 error = SYSCTL_OUT(req, &xig, sizeof xig); 2626 if (error) 2627 return (error); 2628 2629 error = syncache_pcblist(req); 2630 if (error) 2631 return (error); 2632 2633 while ((inp = inp_next(&inpi)) != NULL) { 2634 if (inp->inp_gencnt <= xig.xig_gen && 2635 cr_canseeinpcb(req->td->td_ucred, inp) == 0) { 2636 struct xtcpcb xt; 2637 2638 tcp_inptoxtp(inp, &xt); 2639 error = SYSCTL_OUT(req, &xt, sizeof xt); 2640 if (error) { 2641 INP_RUNLOCK(inp); 2642 break; 2643 } else 2644 continue; 2645 } 2646 } 2647 2648 if (!error) { 2649 /* 2650 * Give the user an updated idea of our state. 2651 * If the generation differs from what we told 2652 * her before, she knows that something happened 2653 * while we were processing this request, and it 2654 * might be necessary to retry. 2655 */ 2656 xig.xig_gen = V_tcbinfo.ipi_gencnt; 2657 xig.xig_sogen = so_gencnt; 2658 xig.xig_count = V_tcbinfo.ipi_count + 2659 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]); 2660 error = SYSCTL_OUT(req, &xig, sizeof xig); 2661 } 2662 2663 return (error); 2664 } 2665 2666 SYSCTL_PROC(_net_inet_tcp, TCPCTL_PCBLIST, pcblist, 2667 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_NEEDGIANT, 2668 NULL, 0, tcp_pcblist, "S,xtcpcb", 2669 "List of active TCP connections"); 2670 2671 #ifdef INET 2672 static int 2673 tcp_getcred(SYSCTL_HANDLER_ARGS) 2674 { 2675 struct xucred xuc; 2676 struct sockaddr_in addrs[2]; 2677 struct epoch_tracker et; 2678 struct inpcb *inp; 2679 int error; 2680 2681 error = priv_check(req->td, PRIV_NETINET_GETCRED); 2682 if (error) 2683 return (error); 2684 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 2685 if (error) 2686 return (error); 2687 NET_EPOCH_ENTER(et); 2688 inp = in_pcblookup(&V_tcbinfo, addrs[1].sin_addr, addrs[1].sin_port, 2689 addrs[0].sin_addr, addrs[0].sin_port, INPLOOKUP_RLOCKPCB, NULL); 2690 NET_EPOCH_EXIT(et); 2691 if (inp != NULL) { 2692 if (error == 0) 2693 error = cr_canseeinpcb(req->td->td_ucred, inp); 2694 if (error == 0) 2695 cru2x(inp->inp_cred, &xuc); 2696 INP_RUNLOCK(inp); 2697 } else 2698 error = ENOENT; 2699 if (error == 0) 2700 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 2701 return (error); 2702 } 2703 2704 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, getcred, 2705 CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_NEEDGIANT, 2706 0, 0, tcp_getcred, "S,xucred", 2707 "Get the xucred of a TCP connection"); 2708 #endif /* INET */ 2709 2710 #ifdef INET6 2711 static int 2712 tcp6_getcred(SYSCTL_HANDLER_ARGS) 2713 { 2714 struct epoch_tracker et; 2715 struct xucred xuc; 2716 struct sockaddr_in6 addrs[2]; 2717 struct inpcb *inp; 2718 int error; 2719 #ifdef INET 2720 int mapped = 0; 2721 #endif 2722 2723 error = priv_check(req->td, PRIV_NETINET_GETCRED); 2724 if (error) 2725 return (error); 2726 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 2727 if (error) 2728 return (error); 2729 if ((error = sa6_embedscope(&addrs[0], V_ip6_use_defzone)) != 0 || 2730 (error = sa6_embedscope(&addrs[1], V_ip6_use_defzone)) != 0) { 2731 return (error); 2732 } 2733 if (IN6_IS_ADDR_V4MAPPED(&addrs[0].sin6_addr)) { 2734 #ifdef INET 2735 if (IN6_IS_ADDR_V4MAPPED(&addrs[1].sin6_addr)) 2736 mapped = 1; 2737 else 2738 #endif 2739 return (EINVAL); 2740 } 2741 2742 NET_EPOCH_ENTER(et); 2743 #ifdef INET 2744 if (mapped == 1) 2745 inp = in_pcblookup(&V_tcbinfo, 2746 *(struct in_addr *)&addrs[1].sin6_addr.s6_addr[12], 2747 addrs[1].sin6_port, 2748 *(struct in_addr *)&addrs[0].sin6_addr.s6_addr[12], 2749 addrs[0].sin6_port, INPLOOKUP_RLOCKPCB, NULL); 2750 else 2751 #endif 2752 inp = in6_pcblookup(&V_tcbinfo, 2753 &addrs[1].sin6_addr, addrs[1].sin6_port, 2754 &addrs[0].sin6_addr, addrs[0].sin6_port, 2755 INPLOOKUP_RLOCKPCB, NULL); 2756 NET_EPOCH_EXIT(et); 2757 if (inp != NULL) { 2758 if (error == 0) 2759 error = cr_canseeinpcb(req->td->td_ucred, inp); 2760 if (error == 0) 2761 cru2x(inp->inp_cred, &xuc); 2762 INP_RUNLOCK(inp); 2763 } else 2764 error = ENOENT; 2765 if (error == 0) 2766 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 2767 return (error); 2768 } 2769 2770 SYSCTL_PROC(_net_inet6_tcp6, OID_AUTO, getcred, 2771 CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_NEEDGIANT, 2772 0, 0, tcp6_getcred, "S,xucred", 2773 "Get the xucred of a TCP6 connection"); 2774 #endif /* INET6 */ 2775 2776 #ifdef INET 2777 /* Path MTU to try next when a fragmentation-needed message is received. */ 2778 static inline int 2779 tcp_next_pmtu(const struct icmp *icp, const struct ip *ip) 2780 { 2781 int mtu = ntohs(icp->icmp_nextmtu); 2782 2783 /* If no alternative MTU was proposed, try the next smaller one. */ 2784 if (!mtu) 2785 mtu = ip_next_mtu(ntohs(ip->ip_len), 1); 2786 if (mtu < V_tcp_minmss + sizeof(struct tcpiphdr)) 2787 mtu = V_tcp_minmss + sizeof(struct tcpiphdr); 2788 2789 return (mtu); 2790 } 2791 2792 static void 2793 tcp_ctlinput_with_port(struct icmp *icp, uint16_t port) 2794 { 2795 struct ip *ip; 2796 struct tcphdr *th; 2797 struct inpcb *inp; 2798 struct tcpcb *tp; 2799 struct inpcb *(*notify)(struct inpcb *, int); 2800 struct in_conninfo inc; 2801 tcp_seq icmp_tcp_seq; 2802 int errno, mtu; 2803 2804 errno = icmp_errmap(icp); 2805 switch (errno) { 2806 case 0: 2807 return; 2808 case EMSGSIZE: 2809 notify = tcp_mtudisc_notify; 2810 break; 2811 case ECONNREFUSED: 2812 if (V_icmp_may_rst) 2813 notify = tcp_drop_syn_sent; 2814 else 2815 notify = tcp_notify; 2816 break; 2817 case EHOSTUNREACH: 2818 if (V_icmp_may_rst && icp->icmp_type == ICMP_TIMXCEED) 2819 notify = tcp_drop_syn_sent; 2820 else 2821 notify = tcp_notify; 2822 break; 2823 default: 2824 notify = tcp_notify; 2825 } 2826 2827 ip = &icp->icmp_ip; 2828 th = (struct tcphdr *)((caddr_t)ip + (ip->ip_hl << 2)); 2829 icmp_tcp_seq = th->th_seq; 2830 inp = in_pcblookup(&V_tcbinfo, ip->ip_dst, th->th_dport, ip->ip_src, 2831 th->th_sport, INPLOOKUP_WLOCKPCB, NULL); 2832 if (inp != NULL) { 2833 tp = intotcpcb(inp); 2834 #ifdef TCP_OFFLOAD 2835 if (tp->t_flags & TF_TOE && errno == EMSGSIZE) { 2836 /* 2837 * MTU discovery for offloaded connections. Let 2838 * the TOE driver verify seq# and process it. 2839 */ 2840 mtu = tcp_next_pmtu(icp, ip); 2841 tcp_offload_pmtu_update(tp, icmp_tcp_seq, mtu); 2842 goto out; 2843 } 2844 #endif 2845 if (tp->t_port != port) 2846 goto out; 2847 if (SEQ_GEQ(ntohl(icmp_tcp_seq), tp->snd_una) && 2848 SEQ_LT(ntohl(icmp_tcp_seq), tp->snd_max)) { 2849 if (errno == EMSGSIZE) { 2850 /* 2851 * MTU discovery: we got a needfrag and 2852 * will potentially try a lower MTU. 2853 */ 2854 mtu = tcp_next_pmtu(icp, ip); 2855 2856 /* 2857 * Only process the offered MTU if it 2858 * is smaller than the current one. 2859 */ 2860 if (mtu < tp->t_maxseg + 2861 sizeof(struct tcpiphdr)) { 2862 bzero(&inc, sizeof(inc)); 2863 inc.inc_faddr = ip->ip_dst; 2864 inc.inc_fibnum = 2865 inp->inp_inc.inc_fibnum; 2866 tcp_hc_updatemtu(&inc, mtu); 2867 inp = tcp_mtudisc(inp, mtu); 2868 } 2869 } else 2870 inp = (*notify)(inp, errno); 2871 } 2872 } else { 2873 bzero(&inc, sizeof(inc)); 2874 inc.inc_fport = th->th_dport; 2875 inc.inc_lport = th->th_sport; 2876 inc.inc_faddr = ip->ip_dst; 2877 inc.inc_laddr = ip->ip_src; 2878 syncache_unreach(&inc, icmp_tcp_seq, port); 2879 } 2880 out: 2881 if (inp != NULL) 2882 INP_WUNLOCK(inp); 2883 } 2884 2885 static void 2886 tcp_ctlinput(struct icmp *icmp) 2887 { 2888 tcp_ctlinput_with_port(icmp, htons(0)); 2889 } 2890 2891 static void 2892 tcp_ctlinput_viaudp(udp_tun_icmp_param_t param) 2893 { 2894 /* Its a tunneled TCP over UDP icmp */ 2895 struct icmp *icmp = param.icmp; 2896 struct ip *outer_ip, *inner_ip; 2897 struct udphdr *udp; 2898 struct tcphdr *th, ttemp; 2899 int i_hlen, o_len; 2900 uint16_t port; 2901 2902 outer_ip = (struct ip *)((caddr_t)icmp - sizeof(struct ip)); 2903 inner_ip = &icmp->icmp_ip; 2904 i_hlen = inner_ip->ip_hl << 2; 2905 o_len = ntohs(outer_ip->ip_len); 2906 if (o_len < 2907 (sizeof(struct ip) + 8 + i_hlen + sizeof(struct udphdr) + offsetof(struct tcphdr, th_ack))) { 2908 /* Not enough data present */ 2909 return; 2910 } 2911 /* Ok lets strip out the inner udphdr header by copying up on top of it the tcp hdr */ 2912 udp = (struct udphdr *)(((caddr_t)inner_ip) + i_hlen); 2913 if (ntohs(udp->uh_sport) != V_tcp_udp_tunneling_port) { 2914 return; 2915 } 2916 port = udp->uh_dport; 2917 th = (struct tcphdr *)(udp + 1); 2918 memcpy(&ttemp, th, sizeof(struct tcphdr)); 2919 memcpy(udp, &ttemp, sizeof(struct tcphdr)); 2920 /* Now adjust down the size of the outer IP header */ 2921 o_len -= sizeof(struct udphdr); 2922 outer_ip->ip_len = htons(o_len); 2923 /* Now call in to the normal handling code */ 2924 tcp_ctlinput_with_port(icmp, port); 2925 } 2926 #endif /* INET */ 2927 2928 #ifdef INET6 2929 static inline int 2930 tcp6_next_pmtu(const struct icmp6_hdr *icmp6) 2931 { 2932 int mtu = ntohl(icmp6->icmp6_mtu); 2933 2934 /* 2935 * If no alternative MTU was proposed, or the proposed MTU was too 2936 * small, set to the min. 2937 */ 2938 if (mtu < IPV6_MMTU) 2939 mtu = IPV6_MMTU - 8; /* XXXNP: what is the adjustment for? */ 2940 return (mtu); 2941 } 2942 2943 static void 2944 tcp6_ctlinput_with_port(struct ip6ctlparam *ip6cp, uint16_t port) 2945 { 2946 struct in6_addr *dst; 2947 struct inpcb *(*notify)(struct inpcb *, int); 2948 struct ip6_hdr *ip6; 2949 struct mbuf *m; 2950 struct inpcb *inp; 2951 struct tcpcb *tp; 2952 struct icmp6_hdr *icmp6; 2953 struct in_conninfo inc; 2954 struct tcp_ports { 2955 uint16_t th_sport; 2956 uint16_t th_dport; 2957 } t_ports; 2958 tcp_seq icmp_tcp_seq; 2959 unsigned int mtu; 2960 unsigned int off; 2961 int errno; 2962 2963 icmp6 = ip6cp->ip6c_icmp6; 2964 m = ip6cp->ip6c_m; 2965 ip6 = ip6cp->ip6c_ip6; 2966 off = ip6cp->ip6c_off; 2967 dst = &ip6cp->ip6c_finaldst->sin6_addr; 2968 2969 errno = icmp6_errmap(icmp6); 2970 switch (errno) { 2971 case 0: 2972 return; 2973 case EMSGSIZE: 2974 notify = tcp_mtudisc_notify; 2975 break; 2976 case ECONNREFUSED: 2977 if (V_icmp_may_rst) 2978 notify = tcp_drop_syn_sent; 2979 else 2980 notify = tcp_notify; 2981 break; 2982 case EHOSTUNREACH: 2983 /* 2984 * There are only four ICMPs that may reset connection: 2985 * - administratively prohibited 2986 * - port unreachable 2987 * - time exceeded in transit 2988 * - unknown next header 2989 */ 2990 if (V_icmp_may_rst && 2991 ((icmp6->icmp6_type == ICMP6_DST_UNREACH && 2992 (icmp6->icmp6_code == ICMP6_DST_UNREACH_ADMIN || 2993 icmp6->icmp6_code == ICMP6_DST_UNREACH_NOPORT)) || 2994 (icmp6->icmp6_type == ICMP6_TIME_EXCEEDED && 2995 icmp6->icmp6_code == ICMP6_TIME_EXCEED_TRANSIT) || 2996 (icmp6->icmp6_type == ICMP6_PARAM_PROB && 2997 icmp6->icmp6_code == ICMP6_PARAMPROB_NEXTHEADER))) 2998 notify = tcp_drop_syn_sent; 2999 else 3000 notify = tcp_notify; 3001 break; 3002 default: 3003 notify = tcp_notify; 3004 } 3005 3006 /* Check if we can safely get the ports from the tcp hdr */ 3007 if (m == NULL || 3008 (m->m_pkthdr.len < 3009 (int32_t) (off + sizeof(struct tcp_ports)))) { 3010 return; 3011 } 3012 bzero(&t_ports, sizeof(struct tcp_ports)); 3013 m_copydata(m, off, sizeof(struct tcp_ports), (caddr_t)&t_ports); 3014 inp = in6_pcblookup(&V_tcbinfo, &ip6->ip6_dst, t_ports.th_dport, 3015 &ip6->ip6_src, t_ports.th_sport, INPLOOKUP_WLOCKPCB, NULL); 3016 off += sizeof(struct tcp_ports); 3017 if (m->m_pkthdr.len < (int32_t) (off + sizeof(tcp_seq))) { 3018 goto out; 3019 } 3020 m_copydata(m, off, sizeof(tcp_seq), (caddr_t)&icmp_tcp_seq); 3021 if (inp != NULL) { 3022 tp = intotcpcb(inp); 3023 #ifdef TCP_OFFLOAD 3024 if (tp->t_flags & TF_TOE && errno == EMSGSIZE) { 3025 /* MTU discovery for offloaded connections. */ 3026 mtu = tcp6_next_pmtu(icmp6); 3027 tcp_offload_pmtu_update(tp, icmp_tcp_seq, mtu); 3028 goto out; 3029 } 3030 #endif 3031 if (tp->t_port != port) 3032 goto out; 3033 if (SEQ_GEQ(ntohl(icmp_tcp_seq), tp->snd_una) && 3034 SEQ_LT(ntohl(icmp_tcp_seq), tp->snd_max)) { 3035 if (errno == EMSGSIZE) { 3036 /* 3037 * MTU discovery: 3038 * If we got a needfrag set the MTU 3039 * in the route to the suggested new 3040 * value (if given) and then notify. 3041 */ 3042 mtu = tcp6_next_pmtu(icmp6); 3043 3044 bzero(&inc, sizeof(inc)); 3045 inc.inc_fibnum = M_GETFIB(m); 3046 inc.inc_flags |= INC_ISIPV6; 3047 inc.inc6_faddr = *dst; 3048 if (in6_setscope(&inc.inc6_faddr, 3049 m->m_pkthdr.rcvif, NULL)) 3050 goto out; 3051 /* 3052 * Only process the offered MTU if it 3053 * is smaller than the current one. 3054 */ 3055 if (mtu < tp->t_maxseg + 3056 sizeof (struct tcphdr) + 3057 sizeof (struct ip6_hdr)) { 3058 tcp_hc_updatemtu(&inc, mtu); 3059 tcp_mtudisc(inp, mtu); 3060 ICMP6STAT_INC(icp6s_pmtuchg); 3061 } 3062 } else 3063 inp = (*notify)(inp, errno); 3064 } 3065 } else { 3066 bzero(&inc, sizeof(inc)); 3067 inc.inc_fibnum = M_GETFIB(m); 3068 inc.inc_flags |= INC_ISIPV6; 3069 inc.inc_fport = t_ports.th_dport; 3070 inc.inc_lport = t_ports.th_sport; 3071 inc.inc6_faddr = *dst; 3072 inc.inc6_laddr = ip6->ip6_src; 3073 syncache_unreach(&inc, icmp_tcp_seq, port); 3074 } 3075 out: 3076 if (inp != NULL) 3077 INP_WUNLOCK(inp); 3078 } 3079 3080 static void 3081 tcp6_ctlinput(struct ip6ctlparam *ctl) 3082 { 3083 tcp6_ctlinput_with_port(ctl, htons(0)); 3084 } 3085 3086 static void 3087 tcp6_ctlinput_viaudp(udp_tun_icmp_param_t param) 3088 { 3089 struct ip6ctlparam *ip6cp = param.ip6cp; 3090 struct mbuf *m; 3091 struct udphdr *udp; 3092 uint16_t port; 3093 3094 m = m_pulldown(ip6cp->ip6c_m, ip6cp->ip6c_off, sizeof(struct udphdr), NULL); 3095 if (m == NULL) { 3096 return; 3097 } 3098 udp = mtod(m, struct udphdr *); 3099 if (ntohs(udp->uh_sport) != V_tcp_udp_tunneling_port) { 3100 return; 3101 } 3102 port = udp->uh_dport; 3103 m_adj(m, sizeof(struct udphdr)); 3104 if ((m->m_flags & M_PKTHDR) == 0) { 3105 ip6cp->ip6c_m->m_pkthdr.len -= sizeof(struct udphdr); 3106 } 3107 /* Now call in to the normal handling code */ 3108 tcp6_ctlinput_with_port(ip6cp, port); 3109 } 3110 3111 #endif /* INET6 */ 3112 3113 static uint32_t 3114 tcp_keyed_hash(struct in_conninfo *inc, u_char *key, u_int len) 3115 { 3116 SIPHASH_CTX ctx; 3117 uint32_t hash[2]; 3118 3119 KASSERT(len >= SIPHASH_KEY_LENGTH, 3120 ("%s: keylen %u too short ", __func__, len)); 3121 SipHash24_Init(&ctx); 3122 SipHash_SetKey(&ctx, (uint8_t *)key); 3123 SipHash_Update(&ctx, &inc->inc_fport, sizeof(uint16_t)); 3124 SipHash_Update(&ctx, &inc->inc_lport, sizeof(uint16_t)); 3125 switch (inc->inc_flags & INC_ISIPV6) { 3126 #ifdef INET 3127 case 0: 3128 SipHash_Update(&ctx, &inc->inc_faddr, sizeof(struct in_addr)); 3129 SipHash_Update(&ctx, &inc->inc_laddr, sizeof(struct in_addr)); 3130 break; 3131 #endif 3132 #ifdef INET6 3133 case INC_ISIPV6: 3134 SipHash_Update(&ctx, &inc->inc6_faddr, sizeof(struct in6_addr)); 3135 SipHash_Update(&ctx, &inc->inc6_laddr, sizeof(struct in6_addr)); 3136 break; 3137 #endif 3138 } 3139 SipHash_Final((uint8_t *)hash, &ctx); 3140 3141 return (hash[0] ^ hash[1]); 3142 } 3143 3144 uint32_t 3145 tcp_new_ts_offset(struct in_conninfo *inc) 3146 { 3147 struct in_conninfo inc_store, *local_inc; 3148 3149 if (!V_tcp_ts_offset_per_conn) { 3150 memcpy(&inc_store, inc, sizeof(struct in_conninfo)); 3151 inc_store.inc_lport = 0; 3152 inc_store.inc_fport = 0; 3153 local_inc = &inc_store; 3154 } else { 3155 local_inc = inc; 3156 } 3157 return (tcp_keyed_hash(local_inc, V_ts_offset_secret, 3158 sizeof(V_ts_offset_secret))); 3159 } 3160 3161 /* 3162 * Following is where TCP initial sequence number generation occurs. 3163 * 3164 * There are two places where we must use initial sequence numbers: 3165 * 1. In SYN-ACK packets. 3166 * 2. In SYN packets. 3167 * 3168 * All ISNs for SYN-ACK packets are generated by the syncache. See 3169 * tcp_syncache.c for details. 3170 * 3171 * The ISNs in SYN packets must be monotonic; TIME_WAIT recycling 3172 * depends on this property. In addition, these ISNs should be 3173 * unguessable so as to prevent connection hijacking. To satisfy 3174 * the requirements of this situation, the algorithm outlined in 3175 * RFC 1948 is used, with only small modifications. 3176 * 3177 * Implementation details: 3178 * 3179 * Time is based off the system timer, and is corrected so that it 3180 * increases by one megabyte per second. This allows for proper 3181 * recycling on high speed LANs while still leaving over an hour 3182 * before rollover. 3183 * 3184 * As reading the *exact* system time is too expensive to be done 3185 * whenever setting up a TCP connection, we increment the time 3186 * offset in two ways. First, a small random positive increment 3187 * is added to isn_offset for each connection that is set up. 3188 * Second, the function tcp_isn_tick fires once per clock tick 3189 * and increments isn_offset as necessary so that sequence numbers 3190 * are incremented at approximately ISN_BYTES_PER_SECOND. The 3191 * random positive increments serve only to ensure that the same 3192 * exact sequence number is never sent out twice (as could otherwise 3193 * happen when a port is recycled in less than the system tick 3194 * interval.) 3195 * 3196 * net.inet.tcp.isn_reseed_interval controls the number of seconds 3197 * between seeding of isn_secret. This is normally set to zero, 3198 * as reseeding should not be necessary. 3199 * 3200 * Locking of the global variables isn_secret, isn_last_reseed, isn_offset, 3201 * isn_offset_old, and isn_ctx is performed using the ISN lock. In 3202 * general, this means holding an exclusive (write) lock. 3203 */ 3204 3205 #define ISN_BYTES_PER_SECOND 1048576 3206 #define ISN_STATIC_INCREMENT 4096 3207 #define ISN_RANDOM_INCREMENT (4096 - 1) 3208 #define ISN_SECRET_LENGTH SIPHASH_KEY_LENGTH 3209 3210 VNET_DEFINE_STATIC(u_char, isn_secret[ISN_SECRET_LENGTH]); 3211 VNET_DEFINE_STATIC(int, isn_last); 3212 VNET_DEFINE_STATIC(int, isn_last_reseed); 3213 VNET_DEFINE_STATIC(u_int32_t, isn_offset); 3214 VNET_DEFINE_STATIC(u_int32_t, isn_offset_old); 3215 3216 #define V_isn_secret VNET(isn_secret) 3217 #define V_isn_last VNET(isn_last) 3218 #define V_isn_last_reseed VNET(isn_last_reseed) 3219 #define V_isn_offset VNET(isn_offset) 3220 #define V_isn_offset_old VNET(isn_offset_old) 3221 3222 tcp_seq 3223 tcp_new_isn(struct in_conninfo *inc) 3224 { 3225 tcp_seq new_isn; 3226 u_int32_t projected_offset; 3227 3228 ISN_LOCK(); 3229 /* Seed if this is the first use, reseed if requested. */ 3230 if ((V_isn_last_reseed == 0) || ((V_tcp_isn_reseed_interval > 0) && 3231 (((u_int)V_isn_last_reseed + (u_int)V_tcp_isn_reseed_interval*hz) 3232 < (u_int)ticks))) { 3233 arc4rand(&V_isn_secret, sizeof(V_isn_secret), 0); 3234 V_isn_last_reseed = ticks; 3235 } 3236 3237 /* Compute the hash and return the ISN. */ 3238 new_isn = (tcp_seq)tcp_keyed_hash(inc, V_isn_secret, 3239 sizeof(V_isn_secret)); 3240 V_isn_offset += ISN_STATIC_INCREMENT + 3241 (arc4random() & ISN_RANDOM_INCREMENT); 3242 if (ticks != V_isn_last) { 3243 projected_offset = V_isn_offset_old + 3244 ISN_BYTES_PER_SECOND / hz * (ticks - V_isn_last); 3245 if (SEQ_GT(projected_offset, V_isn_offset)) 3246 V_isn_offset = projected_offset; 3247 V_isn_offset_old = V_isn_offset; 3248 V_isn_last = ticks; 3249 } 3250 new_isn += V_isn_offset; 3251 ISN_UNLOCK(); 3252 return (new_isn); 3253 } 3254 3255 /* 3256 * When a specific ICMP unreachable message is received and the 3257 * connection state is SYN-SENT, drop the connection. This behavior 3258 * is controlled by the icmp_may_rst sysctl. 3259 */ 3260 static struct inpcb * 3261 tcp_drop_syn_sent(struct inpcb *inp, int errno) 3262 { 3263 struct tcpcb *tp; 3264 3265 NET_EPOCH_ASSERT(); 3266 INP_WLOCK_ASSERT(inp); 3267 3268 tp = intotcpcb(inp); 3269 if (tp->t_state != TCPS_SYN_SENT) 3270 return (inp); 3271 3272 if (IS_FASTOPEN(tp->t_flags)) 3273 tcp_fastopen_disable_path(tp); 3274 3275 tp = tcp_drop(tp, errno); 3276 if (tp != NULL) 3277 return (inp); 3278 else 3279 return (NULL); 3280 } 3281 3282 /* 3283 * When `need fragmentation' ICMP is received, update our idea of the MSS 3284 * based on the new value. Also nudge TCP to send something, since we 3285 * know the packet we just sent was dropped. 3286 * This duplicates some code in the tcp_mss() function in tcp_input.c. 3287 */ 3288 static struct inpcb * 3289 tcp_mtudisc_notify(struct inpcb *inp, int error) 3290 { 3291 3292 return (tcp_mtudisc(inp, -1)); 3293 } 3294 3295 static struct inpcb * 3296 tcp_mtudisc(struct inpcb *inp, int mtuoffer) 3297 { 3298 struct tcpcb *tp; 3299 struct socket *so; 3300 3301 INP_WLOCK_ASSERT(inp); 3302 3303 tp = intotcpcb(inp); 3304 KASSERT(tp != NULL, ("tcp_mtudisc: tp == NULL")); 3305 3306 tcp_mss_update(tp, -1, mtuoffer, NULL, NULL); 3307 3308 so = inp->inp_socket; 3309 SOCKBUF_LOCK(&so->so_snd); 3310 /* If the mss is larger than the socket buffer, decrease the mss. */ 3311 if (so->so_snd.sb_hiwat < tp->t_maxseg) 3312 tp->t_maxseg = so->so_snd.sb_hiwat; 3313 SOCKBUF_UNLOCK(&so->so_snd); 3314 3315 TCPSTAT_INC(tcps_mturesent); 3316 tp->t_rtttime = 0; 3317 tp->snd_nxt = tp->snd_una; 3318 tcp_free_sackholes(tp); 3319 tp->snd_recover = tp->snd_max; 3320 if (tp->t_flags & TF_SACK_PERMIT) 3321 EXIT_FASTRECOVERY(tp->t_flags); 3322 if (tp->t_fb->tfb_tcp_mtu_chg != NULL) { 3323 /* 3324 * Conceptually the snd_nxt setting 3325 * and freeing sack holes should 3326 * be done by the default stacks 3327 * own tfb_tcp_mtu_chg(). 3328 */ 3329 tp->t_fb->tfb_tcp_mtu_chg(tp); 3330 } 3331 if (tcp_output(tp) < 0) 3332 return (NULL); 3333 else 3334 return (inp); 3335 } 3336 3337 #ifdef INET 3338 /* 3339 * Look-up the routing entry to the peer of this inpcb. If no route 3340 * is found and it cannot be allocated, then return 0. This routine 3341 * is called by TCP routines that access the rmx structure and by 3342 * tcp_mss_update to get the peer/interface MTU. 3343 */ 3344 uint32_t 3345 tcp_maxmtu(struct in_conninfo *inc, struct tcp_ifcap *cap) 3346 { 3347 struct nhop_object *nh; 3348 struct ifnet *ifp; 3349 uint32_t maxmtu = 0; 3350 3351 KASSERT(inc != NULL, ("tcp_maxmtu with NULL in_conninfo pointer")); 3352 3353 if (inc->inc_faddr.s_addr != INADDR_ANY) { 3354 nh = fib4_lookup(inc->inc_fibnum, inc->inc_faddr, 0, NHR_NONE, 0); 3355 if (nh == NULL) 3356 return (0); 3357 3358 ifp = nh->nh_ifp; 3359 maxmtu = nh->nh_mtu; 3360 3361 /* Report additional interface capabilities. */ 3362 if (cap != NULL) { 3363 if (ifp->if_capenable & IFCAP_TSO4 && 3364 ifp->if_hwassist & CSUM_TSO) { 3365 cap->ifcap |= CSUM_TSO; 3366 cap->tsomax = ifp->if_hw_tsomax; 3367 cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount; 3368 cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize; 3369 } 3370 } 3371 } 3372 return (maxmtu); 3373 } 3374 #endif /* INET */ 3375 3376 #ifdef INET6 3377 uint32_t 3378 tcp_maxmtu6(struct in_conninfo *inc, struct tcp_ifcap *cap) 3379 { 3380 struct nhop_object *nh; 3381 struct in6_addr dst6; 3382 uint32_t scopeid; 3383 struct ifnet *ifp; 3384 uint32_t maxmtu = 0; 3385 3386 KASSERT(inc != NULL, ("tcp_maxmtu6 with NULL in_conninfo pointer")); 3387 3388 if (inc->inc_flags & INC_IPV6MINMTU) 3389 return (IPV6_MMTU); 3390 3391 if (!IN6_IS_ADDR_UNSPECIFIED(&inc->inc6_faddr)) { 3392 in6_splitscope(&inc->inc6_faddr, &dst6, &scopeid); 3393 nh = fib6_lookup(inc->inc_fibnum, &dst6, scopeid, NHR_NONE, 0); 3394 if (nh == NULL) 3395 return (0); 3396 3397 ifp = nh->nh_ifp; 3398 maxmtu = nh->nh_mtu; 3399 3400 /* Report additional interface capabilities. */ 3401 if (cap != NULL) { 3402 if (ifp->if_capenable & IFCAP_TSO6 && 3403 ifp->if_hwassist & CSUM_TSO) { 3404 cap->ifcap |= CSUM_TSO; 3405 cap->tsomax = ifp->if_hw_tsomax; 3406 cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount; 3407 cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize; 3408 } 3409 } 3410 } 3411 3412 return (maxmtu); 3413 } 3414 3415 /* 3416 * Handle setsockopt(IPV6_USE_MIN_MTU) by a TCP stack. 3417 * 3418 * XXXGL: we are updating inpcb here with INC_IPV6MINMTU flag. 3419 * The right place to do that is ip6_setpktopt() that has just been 3420 * executed. By the way it just filled ip6po_minmtu for us. 3421 */ 3422 void 3423 tcp6_use_min_mtu(struct tcpcb *tp) 3424 { 3425 struct inpcb *inp = tptoinpcb(tp); 3426 3427 INP_WLOCK_ASSERT(inp); 3428 /* 3429 * In case of the IPV6_USE_MIN_MTU socket 3430 * option, the INC_IPV6MINMTU flag to announce 3431 * a corresponding MSS during the initial 3432 * handshake. If the TCP connection is not in 3433 * the front states, just reduce the MSS being 3434 * used. This avoids the sending of TCP 3435 * segments which will be fragmented at the 3436 * IPv6 layer. 3437 */ 3438 inp->inp_inc.inc_flags |= INC_IPV6MINMTU; 3439 if ((tp->t_state >= TCPS_SYN_SENT) && 3440 (inp->inp_inc.inc_flags & INC_ISIPV6)) { 3441 struct ip6_pktopts *opt; 3442 3443 opt = inp->in6p_outputopts; 3444 if (opt != NULL && opt->ip6po_minmtu == IP6PO_MINMTU_ALL && 3445 tp->t_maxseg > TCP6_MSS) 3446 tp->t_maxseg = TCP6_MSS; 3447 } 3448 } 3449 #endif /* INET6 */ 3450 3451 /* 3452 * Calculate effective SMSS per RFC5681 definition for a given TCP 3453 * connection at its current state, taking into account SACK and etc. 3454 */ 3455 u_int 3456 tcp_maxseg(const struct tcpcb *tp) 3457 { 3458 u_int optlen; 3459 3460 if (tp->t_flags & TF_NOOPT) 3461 return (tp->t_maxseg); 3462 3463 /* 3464 * Here we have a simplified code from tcp_addoptions(), 3465 * without a proper loop, and having most of paddings hardcoded. 3466 * We might make mistakes with padding here in some edge cases, 3467 * but this is harmless, since result of tcp_maxseg() is used 3468 * only in cwnd and ssthresh estimations. 3469 */ 3470 if (TCPS_HAVEESTABLISHED(tp->t_state)) { 3471 if (tp->t_flags & TF_RCVD_TSTMP) 3472 optlen = TCPOLEN_TSTAMP_APPA; 3473 else 3474 optlen = 0; 3475 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3476 if (tp->t_flags & TF_SIGNATURE) 3477 optlen += PADTCPOLEN(TCPOLEN_SIGNATURE); 3478 #endif 3479 if ((tp->t_flags & TF_SACK_PERMIT) && tp->rcv_numsacks > 0) { 3480 optlen += TCPOLEN_SACKHDR; 3481 optlen += tp->rcv_numsacks * TCPOLEN_SACK; 3482 optlen = PADTCPOLEN(optlen); 3483 } 3484 } else { 3485 if (tp->t_flags & TF_REQ_TSTMP) 3486 optlen = TCPOLEN_TSTAMP_APPA; 3487 else 3488 optlen = PADTCPOLEN(TCPOLEN_MAXSEG); 3489 if (tp->t_flags & TF_REQ_SCALE) 3490 optlen += PADTCPOLEN(TCPOLEN_WINDOW); 3491 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3492 if (tp->t_flags & TF_SIGNATURE) 3493 optlen += PADTCPOLEN(TCPOLEN_SIGNATURE); 3494 #endif 3495 if (tp->t_flags & TF_SACK_PERMIT) 3496 optlen += PADTCPOLEN(TCPOLEN_SACK_PERMITTED); 3497 } 3498 #undef PAD 3499 optlen = min(optlen, TCP_MAXOLEN); 3500 return (tp->t_maxseg - optlen); 3501 } 3502 3503 3504 u_int 3505 tcp_fixed_maxseg(const struct tcpcb *tp) 3506 { 3507 int optlen; 3508 3509 if (tp->t_flags & TF_NOOPT) 3510 return (tp->t_maxseg); 3511 3512 /* 3513 * Here we have a simplified code from tcp_addoptions(), 3514 * without a proper loop, and having most of paddings hardcoded. 3515 * We only consider fixed options that we would send every 3516 * time I.e. SACK is not considered. This is important 3517 * for cc modules to figure out what the modulo of the 3518 * cwnd should be. 3519 */ 3520 #define PAD(len) ((((len) / 4) + !!((len) % 4)) * 4) 3521 if (TCPS_HAVEESTABLISHED(tp->t_state)) { 3522 if (tp->t_flags & TF_RCVD_TSTMP) 3523 optlen = TCPOLEN_TSTAMP_APPA; 3524 else 3525 optlen = 0; 3526 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3527 if (tp->t_flags & TF_SIGNATURE) 3528 optlen += PAD(TCPOLEN_SIGNATURE); 3529 #endif 3530 } else { 3531 if (tp->t_flags & TF_REQ_TSTMP) 3532 optlen = TCPOLEN_TSTAMP_APPA; 3533 else 3534 optlen = PAD(TCPOLEN_MAXSEG); 3535 if (tp->t_flags & TF_REQ_SCALE) 3536 optlen += PAD(TCPOLEN_WINDOW); 3537 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE) 3538 if (tp->t_flags & TF_SIGNATURE) 3539 optlen += PAD(TCPOLEN_SIGNATURE); 3540 #endif 3541 if (tp->t_flags & TF_SACK_PERMIT) 3542 optlen += PAD(TCPOLEN_SACK_PERMITTED); 3543 } 3544 #undef PAD 3545 optlen = min(optlen, TCP_MAXOLEN); 3546 return (tp->t_maxseg - optlen); 3547 } 3548 3549 3550 3551 static int 3552 sysctl_drop(SYSCTL_HANDLER_ARGS) 3553 { 3554 /* addrs[0] is a foreign socket, addrs[1] is a local one. */ 3555 struct sockaddr_storage addrs[2]; 3556 struct inpcb *inp; 3557 struct tcpcb *tp; 3558 #ifdef INET 3559 struct sockaddr_in *fin = NULL, *lin = NULL; 3560 #endif 3561 struct epoch_tracker et; 3562 #ifdef INET6 3563 struct sockaddr_in6 *fin6, *lin6; 3564 #endif 3565 int error; 3566 3567 inp = NULL; 3568 #ifdef INET6 3569 fin6 = lin6 = NULL; 3570 #endif 3571 error = 0; 3572 3573 if (req->oldptr != NULL || req->oldlen != 0) 3574 return (EINVAL); 3575 if (req->newptr == NULL) 3576 return (EPERM); 3577 if (req->newlen < sizeof(addrs)) 3578 return (ENOMEM); 3579 error = SYSCTL_IN(req, &addrs, sizeof(addrs)); 3580 if (error) 3581 return (error); 3582 3583 switch (addrs[0].ss_family) { 3584 #ifdef INET6 3585 case AF_INET6: 3586 fin6 = (struct sockaddr_in6 *)&addrs[0]; 3587 lin6 = (struct sockaddr_in6 *)&addrs[1]; 3588 if (fin6->sin6_len != sizeof(struct sockaddr_in6) || 3589 lin6->sin6_len != sizeof(struct sockaddr_in6)) 3590 return (EINVAL); 3591 if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr)) { 3592 if (!IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr)) 3593 return (EINVAL); 3594 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[0]); 3595 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[1]); 3596 #ifdef INET 3597 fin = (struct sockaddr_in *)&addrs[0]; 3598 lin = (struct sockaddr_in *)&addrs[1]; 3599 #endif 3600 break; 3601 } 3602 error = sa6_embedscope(fin6, V_ip6_use_defzone); 3603 if (error) 3604 return (error); 3605 error = sa6_embedscope(lin6, V_ip6_use_defzone); 3606 if (error) 3607 return (error); 3608 break; 3609 #endif 3610 #ifdef INET 3611 case AF_INET: 3612 fin = (struct sockaddr_in *)&addrs[0]; 3613 lin = (struct sockaddr_in *)&addrs[1]; 3614 if (fin->sin_len != sizeof(struct sockaddr_in) || 3615 lin->sin_len != sizeof(struct sockaddr_in)) 3616 return (EINVAL); 3617 break; 3618 #endif 3619 default: 3620 return (EINVAL); 3621 } 3622 NET_EPOCH_ENTER(et); 3623 switch (addrs[0].ss_family) { 3624 #ifdef INET6 3625 case AF_INET6: 3626 inp = in6_pcblookup(&V_tcbinfo, &fin6->sin6_addr, 3627 fin6->sin6_port, &lin6->sin6_addr, lin6->sin6_port, 3628 INPLOOKUP_WLOCKPCB, NULL); 3629 break; 3630 #endif 3631 #ifdef INET 3632 case AF_INET: 3633 inp = in_pcblookup(&V_tcbinfo, fin->sin_addr, fin->sin_port, 3634 lin->sin_addr, lin->sin_port, INPLOOKUP_WLOCKPCB, NULL); 3635 break; 3636 #endif 3637 } 3638 if (inp != NULL) { 3639 if (!SOLISTENING(inp->inp_socket)) { 3640 tp = intotcpcb(inp); 3641 tp = tcp_drop(tp, ECONNABORTED); 3642 if (tp != NULL) 3643 INP_WUNLOCK(inp); 3644 } else 3645 INP_WUNLOCK(inp); 3646 } else 3647 error = ESRCH; 3648 NET_EPOCH_EXIT(et); 3649 return (error); 3650 } 3651 3652 SYSCTL_PROC(_net_inet_tcp, TCPCTL_DROP, drop, 3653 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | 3654 CTLFLAG_NEEDGIANT, NULL, 0, sysctl_drop, "", 3655 "Drop TCP connection"); 3656 3657 static int 3658 tcp_sysctl_setsockopt(SYSCTL_HANDLER_ARGS) 3659 { 3660 return (sysctl_setsockopt(oidp, arg1, arg2, req, &V_tcbinfo, 3661 &tcp_ctloutput_set)); 3662 } 3663 3664 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, setsockopt, 3665 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | 3666 CTLFLAG_MPSAFE, NULL, 0, tcp_sysctl_setsockopt, "", 3667 "Set socket option for TCP endpoint"); 3668 3669 #ifdef KERN_TLS 3670 static int 3671 sysctl_switch_tls(SYSCTL_HANDLER_ARGS) 3672 { 3673 /* addrs[0] is a foreign socket, addrs[1] is a local one. */ 3674 struct sockaddr_storage addrs[2]; 3675 struct inpcb *inp; 3676 #ifdef INET 3677 struct sockaddr_in *fin = NULL, *lin = NULL; 3678 #endif 3679 struct epoch_tracker et; 3680 #ifdef INET6 3681 struct sockaddr_in6 *fin6, *lin6; 3682 #endif 3683 int error; 3684 3685 inp = NULL; 3686 #ifdef INET6 3687 fin6 = lin6 = NULL; 3688 #endif 3689 error = 0; 3690 3691 if (req->oldptr != NULL || req->oldlen != 0) 3692 return (EINVAL); 3693 if (req->newptr == NULL) 3694 return (EPERM); 3695 if (req->newlen < sizeof(addrs)) 3696 return (ENOMEM); 3697 error = SYSCTL_IN(req, &addrs, sizeof(addrs)); 3698 if (error) 3699 return (error); 3700 3701 switch (addrs[0].ss_family) { 3702 #ifdef INET6 3703 case AF_INET6: 3704 fin6 = (struct sockaddr_in6 *)&addrs[0]; 3705 lin6 = (struct sockaddr_in6 *)&addrs[1]; 3706 if (fin6->sin6_len != sizeof(struct sockaddr_in6) || 3707 lin6->sin6_len != sizeof(struct sockaddr_in6)) 3708 return (EINVAL); 3709 if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr)) { 3710 if (!IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr)) 3711 return (EINVAL); 3712 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[0]); 3713 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[1]); 3714 #ifdef INET 3715 fin = (struct sockaddr_in *)&addrs[0]; 3716 lin = (struct sockaddr_in *)&addrs[1]; 3717 #endif 3718 break; 3719 } 3720 error = sa6_embedscope(fin6, V_ip6_use_defzone); 3721 if (error) 3722 return (error); 3723 error = sa6_embedscope(lin6, V_ip6_use_defzone); 3724 if (error) 3725 return (error); 3726 break; 3727 #endif 3728 #ifdef INET 3729 case AF_INET: 3730 fin = (struct sockaddr_in *)&addrs[0]; 3731 lin = (struct sockaddr_in *)&addrs[1]; 3732 if (fin->sin_len != sizeof(struct sockaddr_in) || 3733 lin->sin_len != sizeof(struct sockaddr_in)) 3734 return (EINVAL); 3735 break; 3736 #endif 3737 default: 3738 return (EINVAL); 3739 } 3740 NET_EPOCH_ENTER(et); 3741 switch (addrs[0].ss_family) { 3742 #ifdef INET6 3743 case AF_INET6: 3744 inp = in6_pcblookup(&V_tcbinfo, &fin6->sin6_addr, 3745 fin6->sin6_port, &lin6->sin6_addr, lin6->sin6_port, 3746 INPLOOKUP_WLOCKPCB, NULL); 3747 break; 3748 #endif 3749 #ifdef INET 3750 case AF_INET: 3751 inp = in_pcblookup(&V_tcbinfo, fin->sin_addr, fin->sin_port, 3752 lin->sin_addr, lin->sin_port, INPLOOKUP_WLOCKPCB, NULL); 3753 break; 3754 #endif 3755 } 3756 NET_EPOCH_EXIT(et); 3757 if (inp != NULL) { 3758 struct socket *so; 3759 3760 so = inp->inp_socket; 3761 soref(so); 3762 error = ktls_set_tx_mode(so, 3763 arg2 == 0 ? TCP_TLS_MODE_SW : TCP_TLS_MODE_IFNET); 3764 INP_WUNLOCK(inp); 3765 sorele(so); 3766 } else 3767 error = ESRCH; 3768 return (error); 3769 } 3770 3771 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, switch_to_sw_tls, 3772 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | 3773 CTLFLAG_NEEDGIANT, NULL, 0, sysctl_switch_tls, "", 3774 "Switch TCP connection to SW TLS"); 3775 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, switch_to_ifnet_tls, 3776 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP | 3777 CTLFLAG_NEEDGIANT, NULL, 1, sysctl_switch_tls, "", 3778 "Switch TCP connection to ifnet TLS"); 3779 #endif 3780 3781 /* 3782 * Generate a standardized TCP log line for use throughout the 3783 * tcp subsystem. Memory allocation is done with M_NOWAIT to 3784 * allow use in the interrupt context. 3785 * 3786 * NB: The caller MUST free(s, M_TCPLOG) the returned string. 3787 * NB: The function may return NULL if memory allocation failed. 3788 * 3789 * Due to header inclusion and ordering limitations the struct ip 3790 * and ip6_hdr pointers have to be passed as void pointers. 3791 */ 3792 char * 3793 tcp_log_vain(struct in_conninfo *inc, struct tcphdr *th, const void *ip4hdr, 3794 const void *ip6hdr) 3795 { 3796 3797 /* Is logging enabled? */ 3798 if (V_tcp_log_in_vain == 0) 3799 return (NULL); 3800 3801 return (tcp_log_addr(inc, th, ip4hdr, ip6hdr)); 3802 } 3803 3804 char * 3805 tcp_log_addrs(struct in_conninfo *inc, struct tcphdr *th, const void *ip4hdr, 3806 const void *ip6hdr) 3807 { 3808 3809 /* Is logging enabled? */ 3810 if (tcp_log_debug == 0) 3811 return (NULL); 3812 3813 return (tcp_log_addr(inc, th, ip4hdr, ip6hdr)); 3814 } 3815 3816 static char * 3817 tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th, const void *ip4hdr, 3818 const void *ip6hdr) 3819 { 3820 char *s, *sp; 3821 size_t size; 3822 #ifdef INET 3823 const struct ip *ip = (const struct ip *)ip4hdr; 3824 #endif 3825 #ifdef INET6 3826 const struct ip6_hdr *ip6 = (const struct ip6_hdr *)ip6hdr; 3827 #endif /* INET6 */ 3828 3829 /* 3830 * The log line looks like this: 3831 * "TCP: [1.2.3.4]:50332 to [1.2.3.4]:80 tcpflags 0x2<SYN>" 3832 */ 3833 size = sizeof("TCP: []:12345 to []:12345 tcpflags 0x2<>") + 3834 sizeof(PRINT_TH_FLAGS) + 1 + 3835 #ifdef INET6 3836 2 * INET6_ADDRSTRLEN; 3837 #else 3838 2 * INET_ADDRSTRLEN; 3839 #endif /* INET6 */ 3840 3841 s = malloc(size, M_TCPLOG, M_ZERO|M_NOWAIT); 3842 if (s == NULL) 3843 return (NULL); 3844 3845 strcat(s, "TCP: ["); 3846 sp = s + strlen(s); 3847 3848 if (inc && ((inc->inc_flags & INC_ISIPV6) == 0)) { 3849 inet_ntoa_r(inc->inc_faddr, sp); 3850 sp = s + strlen(s); 3851 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport)); 3852 sp = s + strlen(s); 3853 inet_ntoa_r(inc->inc_laddr, sp); 3854 sp = s + strlen(s); 3855 sprintf(sp, "]:%i", ntohs(inc->inc_lport)); 3856 #ifdef INET6 3857 } else if (inc) { 3858 ip6_sprintf(sp, &inc->inc6_faddr); 3859 sp = s + strlen(s); 3860 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport)); 3861 sp = s + strlen(s); 3862 ip6_sprintf(sp, &inc->inc6_laddr); 3863 sp = s + strlen(s); 3864 sprintf(sp, "]:%i", ntohs(inc->inc_lport)); 3865 } else if (ip6 && th) { 3866 ip6_sprintf(sp, &ip6->ip6_src); 3867 sp = s + strlen(s); 3868 sprintf(sp, "]:%i to [", ntohs(th->th_sport)); 3869 sp = s + strlen(s); 3870 ip6_sprintf(sp, &ip6->ip6_dst); 3871 sp = s + strlen(s); 3872 sprintf(sp, "]:%i", ntohs(th->th_dport)); 3873 #endif /* INET6 */ 3874 #ifdef INET 3875 } else if (ip && th) { 3876 inet_ntoa_r(ip->ip_src, sp); 3877 sp = s + strlen(s); 3878 sprintf(sp, "]:%i to [", ntohs(th->th_sport)); 3879 sp = s + strlen(s); 3880 inet_ntoa_r(ip->ip_dst, sp); 3881 sp = s + strlen(s); 3882 sprintf(sp, "]:%i", ntohs(th->th_dport)); 3883 #endif /* INET */ 3884 } else { 3885 free(s, M_TCPLOG); 3886 return (NULL); 3887 } 3888 sp = s + strlen(s); 3889 if (th) 3890 sprintf(sp, " tcpflags 0x%b", tcp_get_flags(th), PRINT_TH_FLAGS); 3891 if (*(s + size - 1) != '\0') 3892 panic("%s: string too long", __func__); 3893 return (s); 3894 } 3895 3896 /* 3897 * A subroutine which makes it easy to track TCP state changes with DTrace. 3898 * This function shouldn't be called for t_state initializations that don't 3899 * correspond to actual TCP state transitions. 3900 */ 3901 void 3902 tcp_state_change(struct tcpcb *tp, int newstate) 3903 { 3904 #if defined(KDTRACE_HOOKS) 3905 int pstate = tp->t_state; 3906 #endif 3907 3908 TCPSTATES_DEC(tp->t_state); 3909 TCPSTATES_INC(newstate); 3910 tp->t_state = newstate; 3911 TCP_PROBE6(state__change, NULL, tp, NULL, tp, NULL, pstate); 3912 } 3913 3914 /* 3915 * Create an external-format (``xtcpcb'') structure using the information in 3916 * the kernel-format tcpcb structure pointed to by tp. This is done to 3917 * reduce the spew of irrelevant information over this interface, to isolate 3918 * user code from changes in the kernel structure, and potentially to provide 3919 * information-hiding if we decide that some of this information should be 3920 * hidden from users. 3921 */ 3922 void 3923 tcp_inptoxtp(const struct inpcb *inp, struct xtcpcb *xt) 3924 { 3925 struct tcpcb *tp = intotcpcb(inp); 3926 sbintime_t now; 3927 3928 bzero(xt, sizeof(*xt)); 3929 xt->t_state = tp->t_state; 3930 xt->t_logstate = tcp_get_bblog_state(tp); 3931 xt->t_flags = tp->t_flags; 3932 xt->t_sndzerowin = tp->t_sndzerowin; 3933 xt->t_sndrexmitpack = tp->t_sndrexmitpack; 3934 xt->t_rcvoopack = tp->t_rcvoopack; 3935 xt->t_rcv_wnd = tp->rcv_wnd; 3936 xt->t_snd_wnd = tp->snd_wnd; 3937 xt->t_snd_cwnd = tp->snd_cwnd; 3938 xt->t_snd_ssthresh = tp->snd_ssthresh; 3939 xt->t_dsack_bytes = tp->t_dsack_bytes; 3940 xt->t_dsack_tlp_bytes = tp->t_dsack_tlp_bytes; 3941 xt->t_dsack_pack = tp->t_dsack_pack; 3942 xt->t_maxseg = tp->t_maxseg; 3943 xt->xt_ecn = (tp->t_flags2 & TF2_ECN_PERMIT) ? 1 : 0 + 3944 (tp->t_flags2 & TF2_ACE_PERMIT) ? 2 : 0; 3945 3946 now = getsbinuptime(); 3947 #define COPYTIMER(which,where) do { \ 3948 if (tp->t_timers[which] != SBT_MAX) \ 3949 xt->where = (tp->t_timers[which] - now) / SBT_1MS; \ 3950 else \ 3951 xt->where = 0; \ 3952 } while (0) 3953 COPYTIMER(TT_DELACK, tt_delack); 3954 COPYTIMER(TT_REXMT, tt_rexmt); 3955 COPYTIMER(TT_PERSIST, tt_persist); 3956 COPYTIMER(TT_KEEP, tt_keep); 3957 COPYTIMER(TT_2MSL, tt_2msl); 3958 #undef COPYTIMER 3959 xt->t_rcvtime = 1000 * (ticks - tp->t_rcvtime) / hz; 3960 3961 xt->xt_encaps_port = tp->t_port; 3962 bcopy(tp->t_fb->tfb_tcp_block_name, xt->xt_stack, 3963 TCP_FUNCTION_NAME_LEN_MAX); 3964 bcopy(CC_ALGO(tp)->name, xt->xt_cc, TCP_CA_NAME_MAX); 3965 #ifdef TCP_BLACKBOX 3966 (void)tcp_log_get_id(tp, xt->xt_logid); 3967 #endif 3968 3969 xt->xt_len = sizeof(struct xtcpcb); 3970 in_pcbtoxinpcb(inp, &xt->xt_inp); 3971 /* 3972 * TCP doesn't use inp_ppcb pointer, we embed inpcb into tcpcb. 3973 * Fixup the pointer that in_pcbtoxinpcb() has set. When printing 3974 * TCP netstat(1) used to use this pointer, so this fixup needs to 3975 * stay for stable/14. 3976 */ 3977 xt->xt_inp.inp_ppcb = (uintptr_t)tp; 3978 } 3979 3980 void 3981 tcp_log_end_status(struct tcpcb *tp, uint8_t status) 3982 { 3983 uint32_t bit, i; 3984 3985 if ((tp == NULL) || 3986 (status > TCP_EI_STATUS_MAX_VALUE) || 3987 (status == 0)) { 3988 /* Invalid */ 3989 return; 3990 } 3991 if (status > (sizeof(uint32_t) * 8)) { 3992 /* Should this be a KASSERT? */ 3993 return; 3994 } 3995 bit = 1U << (status - 1); 3996 if (bit & tp->t_end_info_status) { 3997 /* already logged */ 3998 return; 3999 } 4000 for (i = 0; i < TCP_END_BYTE_INFO; i++) { 4001 if (tp->t_end_info_bytes[i] == TCP_EI_EMPTY_SLOT) { 4002 tp->t_end_info_bytes[i] = status; 4003 tp->t_end_info_status |= bit; 4004 break; 4005 } 4006 } 4007 } 4008 4009 int 4010 tcp_can_enable_pacing(void) 4011 { 4012 4013 if ((tcp_pacing_limit == -1) || 4014 (tcp_pacing_limit > number_of_tcp_connections_pacing)) { 4015 atomic_fetchadd_int(&number_of_tcp_connections_pacing, 1); 4016 shadow_num_connections = number_of_tcp_connections_pacing; 4017 return (1); 4018 } else { 4019 counter_u64_add(tcp_pacing_failures, 1); 4020 return (0); 4021 } 4022 } 4023 4024 static uint8_t tcp_pacing_warning = 0; 4025 4026 void 4027 tcp_decrement_paced_conn(void) 4028 { 4029 uint32_t ret; 4030 4031 ret = atomic_fetchadd_int(&number_of_tcp_connections_pacing, -1); 4032 shadow_num_connections = number_of_tcp_connections_pacing; 4033 KASSERT(ret != 0, ("tcp_paced_connection_exits -1 would cause wrap?")); 4034 if (ret == 0) { 4035 if (tcp_pacing_limit != -1) { 4036 printf("Warning all pacing is now disabled, count decrements invalidly!\n"); 4037 tcp_pacing_limit = 0; 4038 } else if (tcp_pacing_warning == 0) { 4039 printf("Warning pacing count is invalid, invalid decrement\n"); 4040 tcp_pacing_warning = 1; 4041 } 4042 } 4043 } 4044 4045 static void 4046 tcp_default_switch_failed(struct tcpcb *tp) 4047 { 4048 /* 4049 * If a switch fails we only need to 4050 * care about two things: 4051 * a) The t_flags2 4052 * and 4053 * b) The timer granularity. 4054 * Timeouts, at least for now, don't use the 4055 * old callout system in the other stacks so 4056 * those are hopefully safe. 4057 */ 4058 tcp_lro_features_off(tp); 4059 tcp_change_time_units(tp, TCP_TMR_GRANULARITY_TICKS); 4060 } 4061 4062 #ifdef TCP_ACCOUNTING 4063 int 4064 tcp_do_ack_accounting(struct tcpcb *tp, struct tcphdr *th, struct tcpopt *to, uint32_t tiwin, int mss) 4065 { 4066 if (SEQ_LT(th->th_ack, tp->snd_una)) { 4067 /* Do we have a SACK? */ 4068 if (to->to_flags & TOF_SACK) { 4069 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4070 tp->tcp_cnt_counters[ACK_SACK]++; 4071 } 4072 return (ACK_SACK); 4073 } else { 4074 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4075 tp->tcp_cnt_counters[ACK_BEHIND]++; 4076 } 4077 return (ACK_BEHIND); 4078 } 4079 } else if (th->th_ack == tp->snd_una) { 4080 /* Do we have a SACK? */ 4081 if (to->to_flags & TOF_SACK) { 4082 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4083 tp->tcp_cnt_counters[ACK_SACK]++; 4084 } 4085 return (ACK_SACK); 4086 } else if (tiwin != tp->snd_wnd) { 4087 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4088 tp->tcp_cnt_counters[ACK_RWND]++; 4089 } 4090 return (ACK_RWND); 4091 } else { 4092 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4093 tp->tcp_cnt_counters[ACK_DUPACK]++; 4094 } 4095 return (ACK_DUPACK); 4096 } 4097 } else { 4098 if (!SEQ_GT(th->th_ack, tp->snd_max)) { 4099 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4100 tp->tcp_cnt_counters[CNT_OF_ACKS_IN] += (((th->th_ack - tp->snd_una) + mss - 1)/mss); 4101 } 4102 } 4103 if (to->to_flags & TOF_SACK) { 4104 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4105 tp->tcp_cnt_counters[ACK_CUMACK_SACK]++; 4106 } 4107 return (ACK_CUMACK_SACK); 4108 } else { 4109 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) { 4110 tp->tcp_cnt_counters[ACK_CUMACK]++; 4111 } 4112 return (ACK_CUMACK); 4113 } 4114 } 4115 } 4116 #endif 4117 4118 void 4119 tcp_change_time_units(struct tcpcb *tp, int granularity) 4120 { 4121 if (tp->t_tmr_granularity == granularity) { 4122 /* We are there */ 4123 return; 4124 } 4125 if (granularity == TCP_TMR_GRANULARITY_USEC) { 4126 KASSERT((tp->t_tmr_granularity == TCP_TMR_GRANULARITY_TICKS), 4127 ("Granularity is not TICKS its %u in tp:%p", 4128 tp->t_tmr_granularity, tp)); 4129 tp->t_rttlow = TICKS_2_USEC(tp->t_rttlow); 4130 if (tp->t_srtt > 1) { 4131 uint32_t val, frac; 4132 4133 val = tp->t_srtt >> TCP_RTT_SHIFT; 4134 frac = tp->t_srtt & 0x1f; 4135 tp->t_srtt = TICKS_2_USEC(val); 4136 /* 4137 * frac is the fractional part of the srtt (if any) 4138 * but its in ticks and every bit represents 4139 * 1/32nd of a hz. 4140 */ 4141 if (frac) { 4142 if (hz == 1000) { 4143 frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_MSEC) / (uint64_t)TCP_RTT_SCALE); 4144 } else { 4145 frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_SEC) / ((uint64_t)(hz) * (uint64_t)TCP_RTT_SCALE)); 4146 } 4147 tp->t_srtt += frac; 4148 } 4149 } 4150 if (tp->t_rttvar) { 4151 uint32_t val, frac; 4152 4153 val = tp->t_rttvar >> TCP_RTTVAR_SHIFT; 4154 frac = tp->t_rttvar & 0x1f; 4155 tp->t_rttvar = TICKS_2_USEC(val); 4156 /* 4157 * frac is the fractional part of the srtt (if any) 4158 * but its in ticks and every bit represents 4159 * 1/32nd of a hz. 4160 */ 4161 if (frac) { 4162 if (hz == 1000) { 4163 frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_MSEC) / (uint64_t)TCP_RTT_SCALE); 4164 } else { 4165 frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_SEC) / ((uint64_t)(hz) * (uint64_t)TCP_RTT_SCALE)); 4166 } 4167 tp->t_rttvar += frac; 4168 } 4169 } 4170 tp->t_tmr_granularity = TCP_TMR_GRANULARITY_USEC; 4171 } else if (granularity == TCP_TMR_GRANULARITY_TICKS) { 4172 /* Convert back to ticks, with */ 4173 KASSERT((tp->t_tmr_granularity == TCP_TMR_GRANULARITY_USEC), 4174 ("Granularity is not USEC its %u in tp:%p", 4175 tp->t_tmr_granularity, tp)); 4176 if (tp->t_srtt > 1) { 4177 uint32_t val, frac; 4178 4179 val = USEC_2_TICKS(tp->t_srtt); 4180 frac = tp->t_srtt % (HPTS_USEC_IN_SEC / hz); 4181 tp->t_srtt = val << TCP_RTT_SHIFT; 4182 /* 4183 * frac is the fractional part here is left 4184 * over from converting to hz and shifting. 4185 * We need to convert this to the 5 bit 4186 * remainder. 4187 */ 4188 if (frac) { 4189 if (hz == 1000) { 4190 frac = (((uint64_t)frac * (uint64_t)TCP_RTT_SCALE) / (uint64_t)HPTS_USEC_IN_MSEC); 4191 } else { 4192 frac = (((uint64_t)frac * (uint64_t)(hz) * (uint64_t)TCP_RTT_SCALE) /(uint64_t)HPTS_USEC_IN_SEC); 4193 } 4194 tp->t_srtt += frac; 4195 } 4196 } 4197 if (tp->t_rttvar) { 4198 uint32_t val, frac; 4199 4200 val = USEC_2_TICKS(tp->t_rttvar); 4201 frac = tp->t_srtt % (HPTS_USEC_IN_SEC / hz); 4202 tp->t_rttvar = val << TCP_RTTVAR_SHIFT; 4203 /* 4204 * frac is the fractional part here is left 4205 * over from converting to hz and shifting. 4206 * We need to convert this to the 5 bit 4207 * remainder. 4208 */ 4209 if (frac) { 4210 if (hz == 1000) { 4211 frac = (((uint64_t)frac * (uint64_t)TCP_RTT_SCALE) / (uint64_t)HPTS_USEC_IN_MSEC); 4212 } else { 4213 frac = (((uint64_t)frac * (uint64_t)(hz) * (uint64_t)TCP_RTT_SCALE) /(uint64_t)HPTS_USEC_IN_SEC); 4214 } 4215 tp->t_rttvar += frac; 4216 } 4217 } 4218 tp->t_rttlow = USEC_2_TICKS(tp->t_rttlow); 4219 tp->t_tmr_granularity = TCP_TMR_GRANULARITY_TICKS; 4220 } 4221 #ifdef INVARIANTS 4222 else { 4223 panic("Unknown granularity:%d tp:%p", 4224 granularity, tp); 4225 } 4226 #endif 4227 } 4228 4229 void 4230 tcp_handle_orphaned_packets(struct tcpcb *tp) 4231 { 4232 struct mbuf *save, *m, *prev; 4233 /* 4234 * Called when a stack switch is occuring from the fini() 4235 * of the old stack. We assue the init() as already been 4236 * run of the new stack and it has set the t_flags2 to 4237 * what it supports. This function will then deal with any 4238 * differences i.e. cleanup packets that maybe queued that 4239 * the newstack does not support. 4240 */ 4241 4242 if (tp->t_flags2 & TF2_MBUF_L_ACKS) 4243 return; 4244 if ((tp->t_flags2 & TF2_SUPPORTS_MBUFQ) == 0 && 4245 !STAILQ_EMPTY(&tp->t_inqueue)) { 4246 /* 4247 * It is unsafe to process the packets since a 4248 * reset may be lurking in them (its rare but it 4249 * can occur). If we were to find a RST, then we 4250 * would end up dropping the connection and the 4251 * INP lock, so when we return the caller (tcp_usrreq) 4252 * will blow up when it trys to unlock the inp. 4253 * This new stack does not do any fancy LRO features 4254 * so all we can do is toss the packets. 4255 */ 4256 m = STAILQ_FIRST(&tp->t_inqueue); 4257 STAILQ_INIT(&tp->t_inqueue); 4258 STAILQ_FOREACH_FROM_SAFE(m, &tp->t_inqueue, m_stailqpkt, save) 4259 m_freem(m); 4260 } else { 4261 /* 4262 * Here we have a stack that does mbuf queuing but 4263 * does not support compressed ack's. We must 4264 * walk all the mbufs and discard any compressed acks. 4265 */ 4266 STAILQ_FOREACH_SAFE(m, &tp->t_inqueue, m_stailqpkt, save) { 4267 if (m->m_flags & M_ACKCMP) { 4268 if (m == STAILQ_FIRST(&tp->t_inqueue)) 4269 STAILQ_REMOVE_HEAD(&tp->t_inqueue, 4270 m_stailqpkt); 4271 else 4272 STAILQ_REMOVE_AFTER(&tp->t_inqueue, 4273 prev, m_stailqpkt); 4274 m_freem(m); 4275 } else 4276 prev = m; 4277 } 4278 } 4279 } 4280 4281 #ifdef TCP_REQUEST_TRK 4282 uint32_t 4283 tcp_estimate_tls_overhead(struct socket *so, uint64_t tls_usr_bytes) 4284 { 4285 #ifdef KERN_TLS 4286 struct ktls_session *tls; 4287 uint32_t rec_oh, records; 4288 4289 tls = so->so_snd.sb_tls_info; 4290 if (tls == NULL) 4291 return (0); 4292 4293 rec_oh = tls->params.tls_hlen + tls->params.tls_tlen; 4294 records = ((tls_usr_bytes + tls->params.max_frame_len - 1)/tls->params.max_frame_len); 4295 return (records * rec_oh); 4296 #else 4297 return (0); 4298 #endif 4299 } 4300 4301 extern uint32_t tcp_stale_entry_time; 4302 uint32_t tcp_stale_entry_time = 250000; 4303 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, usrlog_stale, CTLFLAG_RW, 4304 &tcp_stale_entry_time, 250000, "Time that a tcpreq entry without a sendfile ages out"); 4305 4306 void 4307 tcp_req_log_req_info(struct tcpcb *tp, struct tcp_sendfile_track *req, 4308 uint16_t slot, uint8_t val, uint64_t offset, uint64_t nbytes) 4309 { 4310 if (tcp_bblogging_on(tp)) { 4311 union tcp_log_stackspecific log; 4312 struct timeval tv; 4313 4314 memset(&log.u_bbr, 0, sizeof(log.u_bbr)); 4315 log.u_bbr.inhpts = tcp_in_hpts(tp); 4316 log.u_bbr.flex8 = val; 4317 log.u_bbr.rttProp = req->timestamp; 4318 log.u_bbr.delRate = req->start; 4319 log.u_bbr.cur_del_rate = req->end; 4320 log.u_bbr.flex1 = req->start_seq; 4321 log.u_bbr.flex2 = req->end_seq; 4322 log.u_bbr.flex3 = req->flags; 4323 log.u_bbr.flex4 = ((req->localtime >> 32) & 0x00000000ffffffff); 4324 log.u_bbr.flex5 = (req->localtime & 0x00000000ffffffff); 4325 log.u_bbr.flex7 = slot; 4326 log.u_bbr.bw_inuse = offset; 4327 /* nbytes = flex6 | epoch */ 4328 log.u_bbr.flex6 = ((nbytes >> 32) & 0x00000000ffffffff); 4329 log.u_bbr.epoch = (nbytes & 0x00000000ffffffff); 4330 /* cspr = lt_epoch | pkts_out */ 4331 log.u_bbr.lt_epoch = ((req->cspr >> 32) & 0x00000000ffffffff); 4332 log.u_bbr.pkts_out |= (req->cspr & 0x00000000ffffffff); 4333 log.u_bbr.applimited = tp->t_tcpreq_closed; 4334 log.u_bbr.applimited <<= 8; 4335 log.u_bbr.applimited |= tp->t_tcpreq_open; 4336 log.u_bbr.applimited <<= 8; 4337 log.u_bbr.applimited |= tp->t_tcpreq_req; 4338 log.u_bbr.timeStamp = tcp_get_usecs(&tv); 4339 TCP_LOG_EVENTP(tp, NULL, 4340 &tptosocket(tp)->so_rcv, 4341 &tptosocket(tp)->so_snd, 4342 TCP_LOG_REQ_T, 0, 4343 0, &log, false, &tv); 4344 } 4345 } 4346 4347 void 4348 tcp_req_free_a_slot(struct tcpcb *tp, struct tcp_sendfile_track *ent) 4349 { 4350 if (tp->t_tcpreq_req > 0) 4351 tp->t_tcpreq_req--; 4352 if (ent->flags & TCP_TRK_TRACK_FLG_OPEN) { 4353 if (tp->t_tcpreq_open > 0) 4354 tp->t_tcpreq_open--; 4355 } else { 4356 if (tp->t_tcpreq_closed > 0) 4357 tp->t_tcpreq_closed--; 4358 } 4359 ent->flags = TCP_TRK_TRACK_FLG_EMPTY; 4360 } 4361 4362 static void 4363 tcp_req_check_for_stale_entries(struct tcpcb *tp, uint64_t ts, int rm_oldest) 4364 { 4365 struct tcp_sendfile_track *ent; 4366 uint64_t time_delta, oldest_delta; 4367 int i, oldest, oldest_set = 0, cnt_rm = 0; 4368 4369 for(i = 0; i < MAX_TCP_TRK_REQ; i++) { 4370 ent = &tp->t_tcpreq_info[i]; 4371 if (ent->flags != TCP_TRK_TRACK_FLG_USED) { 4372 /* 4373 * We only care about closed end ranges 4374 * that are allocated and have no sendfile 4375 * ever touching them. They would be in 4376 * state USED. 4377 */ 4378 continue; 4379 } 4380 if (ts >= ent->localtime) 4381 time_delta = ts - ent->localtime; 4382 else 4383 time_delta = 0; 4384 if (time_delta && 4385 ((oldest_delta < time_delta) || (oldest_set == 0))) { 4386 oldest_set = 1; 4387 oldest = i; 4388 oldest_delta = time_delta; 4389 } 4390 if (tcp_stale_entry_time && (time_delta >= tcp_stale_entry_time)) { 4391 /* 4392 * No sendfile in a our time-limit 4393 * time to purge it. 4394 */ 4395 cnt_rm++; 4396 tcp_req_log_req_info(tp, &tp->t_tcpreq_info[i], i, TCP_TRK_REQ_LOG_STALE, 4397 time_delta, 0); 4398 tcp_req_free_a_slot(tp, ent); 4399 } 4400 } 4401 if ((cnt_rm == 0) && rm_oldest && oldest_set) { 4402 ent = &tp->t_tcpreq_info[oldest]; 4403 tcp_req_log_req_info(tp, &tp->t_tcpreq_info[i], i, TCP_TRK_REQ_LOG_STALE, 4404 oldest_delta, 1); 4405 tcp_req_free_a_slot(tp, ent); 4406 } 4407 } 4408 4409 int 4410 tcp_req_check_for_comp(struct tcpcb *tp, tcp_seq ack_point) 4411 { 4412 int i, ret=0; 4413 struct tcp_sendfile_track *ent; 4414 4415 /* Clean up any old closed end requests that are now completed */ 4416 if (tp->t_tcpreq_req == 0) 4417 return(0); 4418 if (tp->t_tcpreq_closed == 0) 4419 return(0); 4420 for(i = 0; i < MAX_TCP_TRK_REQ; i++) { 4421 ent = &tp->t_tcpreq_info[i]; 4422 /* Skip empty ones */ 4423 if (ent->flags == TCP_TRK_TRACK_FLG_EMPTY) 4424 continue; 4425 /* Skip open ones */ 4426 if (ent->flags & TCP_TRK_TRACK_FLG_OPEN) 4427 continue; 4428 if (SEQ_GEQ(ack_point, ent->end_seq)) { 4429 /* We are past it -- free it */ 4430 tcp_req_log_req_info(tp, ent, 4431 i, TCP_TRK_REQ_LOG_FREED, 0, 0); 4432 tcp_req_free_a_slot(tp, ent); 4433 ret++; 4434 } 4435 } 4436 return (ret); 4437 } 4438 4439 int 4440 tcp_req_is_entry_comp(struct tcpcb *tp, struct tcp_sendfile_track *ent, tcp_seq ack_point) 4441 { 4442 if (tp->t_tcpreq_req == 0) 4443 return(-1); 4444 if (tp->t_tcpreq_closed == 0) 4445 return(-1); 4446 if (ent->flags == TCP_TRK_TRACK_FLG_EMPTY) 4447 return(-1); 4448 if (SEQ_GEQ(ack_point, ent->end_seq)) { 4449 return (1); 4450 } 4451 return (0); 4452 } 4453 4454 struct tcp_sendfile_track * 4455 tcp_req_find_a_req_that_is_completed_by(struct tcpcb *tp, tcp_seq th_ack, int *ip) 4456 { 4457 /* 4458 * Given an ack point (th_ack) walk through our entries and 4459 * return the first one found that th_ack goes past the 4460 * end_seq. 4461 */ 4462 struct tcp_sendfile_track *ent; 4463 int i; 4464 4465 if (tp->t_tcpreq_req == 0) { 4466 /* none open */ 4467 return (NULL); 4468 } 4469 for(i = 0; i < MAX_TCP_TRK_REQ; i++) { 4470 ent = &tp->t_tcpreq_info[i]; 4471 if (ent->flags == TCP_TRK_TRACK_FLG_EMPTY) 4472 continue; 4473 if ((ent->flags & TCP_TRK_TRACK_FLG_OPEN) == 0) { 4474 if (SEQ_GEQ(th_ack, ent->end_seq)) { 4475 *ip = i; 4476 return (ent); 4477 } 4478 } 4479 } 4480 return (NULL); 4481 } 4482 4483 struct tcp_sendfile_track * 4484 tcp_req_find_req_for_seq(struct tcpcb *tp, tcp_seq seq) 4485 { 4486 struct tcp_sendfile_track *ent; 4487 int i; 4488 4489 if (tp->t_tcpreq_req == 0) { 4490 /* none open */ 4491 return (NULL); 4492 } 4493 for(i = 0; i < MAX_TCP_TRK_REQ; i++) { 4494 ent = &tp->t_tcpreq_info[i]; 4495 tcp_req_log_req_info(tp, ent, i, TCP_TRK_REQ_LOG_SEARCH, 4496 (uint64_t)seq, 0); 4497 if (ent->flags == TCP_TRK_TRACK_FLG_EMPTY) { 4498 continue; 4499 } 4500 if (ent->flags & TCP_TRK_TRACK_FLG_OPEN) { 4501 /* 4502 * An open end request only needs to 4503 * match the beginning seq or be 4504 * all we have (once we keep going on 4505 * a open end request we may have a seq 4506 * wrap). 4507 */ 4508 if ((SEQ_GEQ(seq, ent->start_seq)) || 4509 (tp->t_tcpreq_closed == 0)) 4510 return (ent); 4511 } else { 4512 /* 4513 * For this one we need to 4514 * be a bit more careful if its 4515 * completed at least. 4516 */ 4517 if ((SEQ_GEQ(seq, ent->start_seq)) && 4518 (SEQ_LT(seq, ent->end_seq))) { 4519 return (ent); 4520 } 4521 } 4522 } 4523 return (NULL); 4524 } 4525 4526 /* Should this be in its own file tcp_req.c ? */ 4527 struct tcp_sendfile_track * 4528 tcp_req_alloc_req_full(struct tcpcb *tp, struct tcp_snd_req *req, uint64_t ts, int rec_dups) 4529 { 4530 struct tcp_sendfile_track *fil; 4531 int i, allocated; 4532 4533 /* In case the stack does not check for completions do so now */ 4534 tcp_req_check_for_comp(tp, tp->snd_una); 4535 /* Check for stale entries */ 4536 if (tp->t_tcpreq_req) 4537 tcp_req_check_for_stale_entries(tp, ts, 4538 (tp->t_tcpreq_req >= MAX_TCP_TRK_REQ)); 4539 /* Check to see if this is a duplicate of one not started */ 4540 if (tp->t_tcpreq_req) { 4541 for(i = 0, allocated = 0; i < MAX_TCP_TRK_REQ; i++) { 4542 fil = &tp->t_tcpreq_info[i]; 4543 if (fil->flags != TCP_TRK_TRACK_FLG_USED) 4544 continue; 4545 if ((fil->timestamp == req->timestamp) && 4546 (fil->start == req->start) && 4547 ((fil->flags & TCP_TRK_TRACK_FLG_OPEN) || 4548 (fil->end == req->end))) { 4549 /* 4550 * We already have this request 4551 * and it has not been started with sendfile. 4552 * This probably means the user was returned 4553 * a 4xx of some sort and its going to age 4554 * out, lets not duplicate it. 4555 */ 4556 return(fil); 4557 } 4558 } 4559 } 4560 /* Ok if there is no room at the inn we are in trouble */ 4561 if (tp->t_tcpreq_req >= MAX_TCP_TRK_REQ) { 4562 tcp_trace_point(tp, TCP_TP_REQ_LOG_FAIL); 4563 for(i = 0; i < MAX_TCP_TRK_REQ; i++) { 4564 tcp_req_log_req_info(tp, &tp->t_tcpreq_info[i], 4565 i, TCP_TRK_REQ_LOG_ALLOCFAIL, 0, 0); 4566 } 4567 return (NULL); 4568 } 4569 for(i = 0, allocated = 0; i < MAX_TCP_TRK_REQ; i++) { 4570 fil = &tp->t_tcpreq_info[i]; 4571 if (fil->flags == TCP_TRK_TRACK_FLG_EMPTY) { 4572 allocated = 1; 4573 fil->flags = TCP_TRK_TRACK_FLG_USED; 4574 fil->timestamp = req->timestamp; 4575 fil->localtime = ts; 4576 fil->start = req->start; 4577 if (req->flags & TCP_LOG_HTTPD_RANGE_END) { 4578 fil->end = req->end; 4579 } else { 4580 fil->end = 0; 4581 fil->flags |= TCP_TRK_TRACK_FLG_OPEN; 4582 } 4583 /* 4584 * We can set the min boundaries to the TCP Sequence space, 4585 * but it might be found to be further up when sendfile 4586 * actually runs on this range (if it ever does). 4587 */ 4588 fil->sbcc_at_s = tptosocket(tp)->so_snd.sb_ccc; 4589 fil->start_seq = tp->snd_una + 4590 tptosocket(tp)->so_snd.sb_ccc; 4591 fil->end_seq = (fil->start_seq + ((uint32_t)(fil->end - fil->start))); 4592 if (tptosocket(tp)->so_snd.sb_tls_info) { 4593 /* 4594 * This session is doing TLS. Take a swag guess 4595 * at the overhead. 4596 */ 4597 fil->end_seq += tcp_estimate_tls_overhead( 4598 tptosocket(tp), (fil->end - fil->start)); 4599 } 4600 tp->t_tcpreq_req++; 4601 if (fil->flags & TCP_TRK_TRACK_FLG_OPEN) 4602 tp->t_tcpreq_open++; 4603 else 4604 tp->t_tcpreq_closed++; 4605 tcp_req_log_req_info(tp, fil, i, 4606 TCP_TRK_REQ_LOG_NEW, 0, 0); 4607 break; 4608 } else 4609 fil = NULL; 4610 } 4611 return (fil); 4612 } 4613 4614 void 4615 tcp_req_alloc_req(struct tcpcb *tp, union tcp_log_userdata *user, uint64_t ts) 4616 { 4617 (void)tcp_req_alloc_req_full(tp, &user->tcp_req, ts, 1); 4618 } 4619 #endif 4620 4621 void 4622 tcp_log_socket_option(struct tcpcb *tp, uint32_t option_num, uint32_t option_val, int err) 4623 { 4624 if (tcp_bblogging_on(tp)) { 4625 struct tcp_log_buffer *l; 4626 4627 l = tcp_log_event(tp, NULL, 4628 &tptosocket(tp)->so_rcv, 4629 &tptosocket(tp)->so_snd, 4630 TCP_LOG_SOCKET_OPT, 4631 err, 0, NULL, 1, 4632 NULL, NULL, 0, NULL); 4633 if (l) { 4634 l->tlb_flex1 = option_num; 4635 l->tlb_flex2 = option_val; 4636 } 4637 } 4638 } 4639 4640 uint32_t 4641 tcp_get_srtt(struct tcpcb *tp, int granularity) 4642 { 4643 uint32_t srtt; 4644 4645 KASSERT(granularity == TCP_TMR_GRANULARITY_USEC || 4646 granularity == TCP_TMR_GRANULARITY_TICKS, 4647 ("%s: called with unexpected granularity %d", __func__, 4648 granularity)); 4649 4650 srtt = tp->t_srtt; 4651 4652 /* 4653 * We only support two granularities. If the stored granularity 4654 * does not match the granularity requested by the caller, 4655 * convert the stored value to the requested unit of granularity. 4656 */ 4657 if (tp->t_tmr_granularity != granularity) { 4658 if (granularity == TCP_TMR_GRANULARITY_USEC) 4659 srtt = TICKS_2_USEC(srtt); 4660 else 4661 srtt = USEC_2_TICKS(srtt); 4662 } 4663 4664 /* 4665 * If the srtt is stored with ticks granularity, we need to 4666 * unshift to get the actual value. We do this after the 4667 * conversion above (if one was necessary) in order to maximize 4668 * precision. 4669 */ 4670 if (tp->t_tmr_granularity == TCP_TMR_GRANULARITY_TICKS) 4671 srtt = srtt >> TCP_RTT_SHIFT; 4672 4673 return (srtt); 4674 } 4675 4676 void 4677 tcp_account_for_send(struct tcpcb *tp, uint32_t len, uint8_t is_rxt, 4678 uint8_t is_tlp, bool hw_tls) 4679 { 4680 4681 if (is_tlp) { 4682 tp->t_sndtlppack++; 4683 tp->t_sndtlpbyte += len; 4684 } 4685 /* To get total bytes sent you must add t_snd_rxt_bytes to t_sndbytes */ 4686 if (is_rxt) 4687 tp->t_snd_rxt_bytes += len; 4688 else 4689 tp->t_sndbytes += len; 4690 4691 #ifdef KERN_TLS 4692 if (hw_tls && is_rxt && len != 0) { 4693 uint64_t rexmit_percent; 4694 4695 rexmit_percent = (1000ULL * tp->t_snd_rxt_bytes) / 4696 (10ULL * (tp->t_snd_rxt_bytes + tp->t_sndbytes)); 4697 if (rexmit_percent > ktls_ifnet_max_rexmit_pct) 4698 ktls_disable_ifnet(tp); 4699 } 4700 #endif 4701 } 4702