1 /* 2 * Copyright (c) 2003, 2004 Jeffrey M. Hsu. All rights reserved. 3 * Copyright (c) 2003, 2004 The DragonFly Project. All rights reserved. 4 * 5 * This code is derived from software contributed to The DragonFly Project 6 * by Jeffrey M. Hsu. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of The DragonFly Project nor the names of its 17 * contributors may be used to endorse or promote products derived 18 * from this software without specific, prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 24 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 27 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 30 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 /* 35 * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995 36 * The Regents of the University of California. All rights reserved. 37 * 38 * Redistribution and use in source and binary forms, with or without 39 * modification, are permitted provided that the following conditions 40 * are met: 41 * 1. Redistributions of source code must retain the above copyright 42 * notice, this list of conditions and the following disclaimer. 43 * 2. Redistributions in binary form must reproduce the above copyright 44 * notice, this list of conditions and the following disclaimer in the 45 * documentation and/or other materials provided with the distribution. 46 * 3. Neither the name of the University nor the names of its contributors 47 * may be used to endorse or promote products derived from this software 48 * without specific prior written permission. 49 * 50 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 51 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 52 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 53 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 54 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 55 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 56 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 57 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 58 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 59 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 60 * SUCH DAMAGE. 61 * 62 * @(#)tcp_subr.c 8.2 (Berkeley) 5/24/95 63 * $FreeBSD: src/sys/netinet/tcp_subr.c,v 1.73.2.31 2003/01/24 05:11:34 sam Exp $ 64 */ 65 66 #include "opt_inet.h" 67 #include "opt_inet6.h" 68 #include "opt_ipsec.h" 69 #include "opt_tcpdebug.h" 70 71 #include <sys/param.h> 72 #include <sys/systm.h> 73 #include <sys/callout.h> 74 #include <sys/kernel.h> 75 #include <sys/sysctl.h> 76 #include <sys/malloc.h> 77 #include <sys/mpipe.h> 78 #include <sys/mbuf.h> 79 #ifdef INET6 80 #include <sys/domain.h> 81 #endif 82 #include <sys/proc.h> 83 #include <sys/priv.h> 84 #include <sys/socket.h> 85 #include <sys/socketops.h> 86 #include <sys/socketvar.h> 87 #include <sys/protosw.h> 88 #include <sys/random.h> 89 #include <sys/in_cksum.h> 90 #include <sys/ktr.h> 91 92 #include <net/route.h> 93 #include <net/if.h> 94 #include <net/netisr2.h> 95 96 #define _IP_VHL 97 #include <netinet/in.h> 98 #include <netinet/in_systm.h> 99 #include <netinet/ip.h> 100 #include <netinet/ip6.h> 101 #include <netinet/in_pcb.h> 102 #include <netinet6/in6_pcb.h> 103 #include <netinet/in_var.h> 104 #include <netinet/ip_var.h> 105 #include <netinet6/ip6_var.h> 106 #include <netinet/ip_icmp.h> 107 #ifdef INET6 108 #include <netinet/icmp6.h> 109 #endif 110 #include <netinet/tcp.h> 111 #include <netinet/tcp_fsm.h> 112 #include <netinet/tcp_seq.h> 113 #include <netinet/tcp_timer.h> 114 #include <netinet/tcp_timer2.h> 115 #include <netinet/tcp_var.h> 116 #include <netinet6/tcp6_var.h> 117 #include <netinet/tcpip.h> 118 #ifdef TCPDEBUG 119 #include <netinet/tcp_debug.h> 120 #endif 121 #include <netinet6/ip6protosw.h> 122 123 #ifdef IPSEC 124 #include <netinet6/ipsec.h> 125 #include <netproto/key/key.h> 126 #ifdef INET6 127 #include <netinet6/ipsec6.h> 128 #endif 129 #endif 130 131 #ifdef FAST_IPSEC 132 #include <netproto/ipsec/ipsec.h> 133 #ifdef INET6 134 #include <netproto/ipsec/ipsec6.h> 135 #endif 136 #define IPSEC 137 #endif 138 139 #include <sys/md5.h> 140 #include <machine/smp.h> 141 142 #include <sys/msgport2.h> 143 #include <sys/mplock2.h> 144 #include <net/netmsg2.h> 145 146 #if !defined(KTR_TCP) 147 #define KTR_TCP KTR_ALL 148 #endif 149 /* 150 KTR_INFO_MASTER(tcp); 151 KTR_INFO(KTR_TCP, tcp, rxmsg, 0, "tcp getmsg", 0); 152 KTR_INFO(KTR_TCP, tcp, wait, 1, "tcp waitmsg", 0); 153 KTR_INFO(KTR_TCP, tcp, delayed, 2, "tcp execute delayed ops", 0); 154 #define logtcp(name) KTR_LOG(tcp_ ## name) 155 */ 156 157 #define TCP_IW_MAXSEGS_DFLT 4 158 #define TCP_IW_CAPSEGS_DFLT 4 159 160 struct tcp_reass_pcpu { 161 int draining; 162 struct netmsg_base drain_nmsg; 163 } __cachealign; 164 165 struct inpcbinfo tcbinfo[MAXCPU]; 166 struct tcpcbackq tcpcbackq[MAXCPU]; 167 struct tcp_reass_pcpu tcp_reassq[MAXCPU]; 168 169 int tcp_mssdflt = TCP_MSS; 170 SYSCTL_INT(_net_inet_tcp, TCPCTL_MSSDFLT, mssdflt, CTLFLAG_RW, 171 &tcp_mssdflt, 0, "Default TCP Maximum Segment Size"); 172 173 #ifdef INET6 174 int tcp_v6mssdflt = TCP6_MSS; 175 SYSCTL_INT(_net_inet_tcp, TCPCTL_V6MSSDFLT, v6mssdflt, CTLFLAG_RW, 176 &tcp_v6mssdflt, 0, "Default TCP Maximum Segment Size for IPv6"); 177 #endif 178 179 /* 180 * Minimum MSS we accept and use. This prevents DoS attacks where 181 * we are forced to a ridiculous low MSS like 20 and send hundreds 182 * of packets instead of one. The effect scales with the available 183 * bandwidth and quickly saturates the CPU and network interface 184 * with packet generation and sending. Set to zero to disable MINMSS 185 * checking. This setting prevents us from sending too small packets. 186 */ 187 int tcp_minmss = TCP_MINMSS; 188 SYSCTL_INT(_net_inet_tcp, OID_AUTO, minmss, CTLFLAG_RW, 189 &tcp_minmss , 0, "Minmum TCP Maximum Segment Size"); 190 191 #if 0 192 static int tcp_rttdflt = TCPTV_SRTTDFLT / PR_SLOWHZ; 193 SYSCTL_INT(_net_inet_tcp, TCPCTL_RTTDFLT, rttdflt, CTLFLAG_RW, 194 &tcp_rttdflt, 0, "Default maximum TCP Round Trip Time"); 195 #endif 196 197 int tcp_do_rfc1323 = 1; 198 SYSCTL_INT(_net_inet_tcp, TCPCTL_DO_RFC1323, rfc1323, CTLFLAG_RW, 199 &tcp_do_rfc1323, 0, "Enable rfc1323 (high performance TCP) extensions"); 200 201 static int tcp_tcbhashsize = 0; 202 SYSCTL_INT(_net_inet_tcp, OID_AUTO, tcbhashsize, CTLFLAG_RD, 203 &tcp_tcbhashsize, 0, "Size of TCP control block hashtable"); 204 205 static int do_tcpdrain = 1; 206 SYSCTL_INT(_net_inet_tcp, OID_AUTO, do_tcpdrain, CTLFLAG_RW, &do_tcpdrain, 0, 207 "Enable tcp_drain routine for extra help when low on mbufs"); 208 209 static int icmp_may_rst = 1; 210 SYSCTL_INT(_net_inet_tcp, OID_AUTO, icmp_may_rst, CTLFLAG_RW, &icmp_may_rst, 0, 211 "Certain ICMP unreachable messages may abort connections in SYN_SENT"); 212 213 static int tcp_isn_reseed_interval = 0; 214 SYSCTL_INT(_net_inet_tcp, OID_AUTO, isn_reseed_interval, CTLFLAG_RW, 215 &tcp_isn_reseed_interval, 0, "Seconds between reseeding of ISN secret"); 216 217 /* 218 * TCP bandwidth limiting sysctls. The inflight limiter is now turned on 219 * by default, but with generous values which should allow maximal 220 * bandwidth. In particular, the slop defaults to 50 (5 packets). 221 * 222 * The reason for doing this is that the limiter is the only mechanism we 223 * have which seems to do a really good job preventing receiver RX rings 224 * on network interfaces from getting blown out. Even though GigE/10GigE 225 * is supposed to flow control it looks like either it doesn't actually 226 * do it or Open Source drivers do not properly enable it. 227 * 228 * People using the limiter to reduce bottlenecks on slower WAN connections 229 * should set the slop to 20 (2 packets). 230 */ 231 static int tcp_inflight_enable = 1; 232 SYSCTL_INT(_net_inet_tcp, OID_AUTO, inflight_enable, CTLFLAG_RW, 233 &tcp_inflight_enable, 0, "Enable automatic TCP inflight data limiting"); 234 235 static int tcp_inflight_debug = 0; 236 SYSCTL_INT(_net_inet_tcp, OID_AUTO, inflight_debug, CTLFLAG_RW, 237 &tcp_inflight_debug, 0, "Debug TCP inflight calculations"); 238 239 /* 240 * NOTE: tcp_inflight_start is essentially the starting receive window 241 * for a connection. If set too low then fetches over tcp 242 * connections will take noticably longer to ramp-up over 243 * high-latency connections. 6144 is too low for a default, 244 * use something more reasonable. 245 */ 246 static int tcp_inflight_start = 33792; 247 SYSCTL_INT(_net_inet_tcp, OID_AUTO, inflight_start, CTLFLAG_RW, 248 &tcp_inflight_start, 0, "Start value for TCP inflight window"); 249 250 static int tcp_inflight_min = 6144; 251 SYSCTL_INT(_net_inet_tcp, OID_AUTO, inflight_min, CTLFLAG_RW, 252 &tcp_inflight_min, 0, "Lower bound for TCP inflight window"); 253 254 static int tcp_inflight_max = TCP_MAXWIN << TCP_MAX_WINSHIFT; 255 SYSCTL_INT(_net_inet_tcp, OID_AUTO, inflight_max, CTLFLAG_RW, 256 &tcp_inflight_max, 0, "Upper bound for TCP inflight window"); 257 258 static int tcp_inflight_stab = 50; 259 SYSCTL_INT(_net_inet_tcp, OID_AUTO, inflight_stab, CTLFLAG_RW, 260 &tcp_inflight_stab, 0, "Fudge bw 1/10% (50=5%)"); 261 262 static int tcp_inflight_adjrtt = 2; 263 SYSCTL_INT(_net_inet_tcp, OID_AUTO, inflight_adjrtt, CTLFLAG_RW, 264 &tcp_inflight_adjrtt, 0, "Slop for rtt 1/(hz*32)"); 265 266 static int tcp_do_rfc3390 = 1; 267 SYSCTL_INT(_net_inet_tcp, OID_AUTO, rfc3390, CTLFLAG_RW, 268 &tcp_do_rfc3390, 0, 269 "Enable RFC 3390 (Increasing TCP's Initial Congestion Window)"); 270 271 static u_long tcp_iw_maxsegs = TCP_IW_MAXSEGS_DFLT; 272 SYSCTL_ULONG(_net_inet_tcp, OID_AUTO, iwmaxsegs, CTLFLAG_RW, 273 &tcp_iw_maxsegs, 0, "TCP IW segments max"); 274 275 static u_long tcp_iw_capsegs = TCP_IW_CAPSEGS_DFLT; 276 SYSCTL_ULONG(_net_inet_tcp, OID_AUTO, iwcapsegs, CTLFLAG_RW, 277 &tcp_iw_capsegs, 0, "TCP IW segments"); 278 279 int tcp_low_rtobase = 1; 280 SYSCTL_INT(_net_inet_tcp, OID_AUTO, low_rtobase, CTLFLAG_RW, 281 &tcp_low_rtobase, 0, "Lowering the Initial RTO (RFC 6298)"); 282 283 static int tcp_do_ncr = 1; 284 SYSCTL_INT(_net_inet_tcp, OID_AUTO, ncr, CTLFLAG_RW, 285 &tcp_do_ncr, 0, "Non-Congestion Robustness (RFC 4653)"); 286 287 int tcp_ncr_linklocal = 0; 288 SYSCTL_INT(_net_inet_tcp, OID_AUTO, ncr_linklocal, CTLFLAG_RW, 289 &tcp_ncr_linklocal, 0, 290 "Enable Non-Congestion Robustness (RFC 4653) on link local network"); 291 292 int tcp_ncr_rxtthresh_max = 16; 293 SYSCTL_INT(_net_inet_tcp, OID_AUTO, ncr_rxtthresh_max, CTLFLAG_RW, 294 &tcp_ncr_rxtthresh_max, 0, 295 "Non-Congestion Robustness (RFC 4653), DupThresh upper limit"); 296 297 static MALLOC_DEFINE(M_TCPTEMP, "tcptemp", "TCP Templates for Keepalives"); 298 static struct malloc_pipe tcptemp_mpipe; 299 300 static void tcp_willblock(void); 301 static void tcp_notify (struct inpcb *, int); 302 303 struct tcp_stats tcpstats_percpu[MAXCPU] __cachealign; 304 struct tcp_state_count tcpstate_count[MAXCPU] __cachealign; 305 306 static void tcp_drain_dispatch(netmsg_t nmsg); 307 308 static int 309 sysctl_tcpstats(SYSCTL_HANDLER_ARGS) 310 { 311 int cpu, error = 0; 312 313 for (cpu = 0; cpu < netisr_ncpus; ++cpu) { 314 if ((error = SYSCTL_OUT(req, &tcpstats_percpu[cpu], 315 sizeof(struct tcp_stats)))) 316 break; 317 if ((error = SYSCTL_IN(req, &tcpstats_percpu[cpu], 318 sizeof(struct tcp_stats)))) 319 break; 320 } 321 322 return (error); 323 } 324 SYSCTL_PROC(_net_inet_tcp, TCPCTL_STATS, stats, (CTLTYPE_OPAQUE | CTLFLAG_RW), 325 0, 0, sysctl_tcpstats, "S,tcp_stats", "TCP statistics"); 326 327 /* 328 * Target size of TCP PCB hash tables. Must be a power of two. 329 * 330 * Note that this can be overridden by the kernel environment 331 * variable net.inet.tcp.tcbhashsize 332 */ 333 #ifndef TCBHASHSIZE 334 #define TCBHASHSIZE 512 335 #endif 336 337 /* 338 * This is the actual shape of what we allocate using the zone 339 * allocator. Doing it this way allows us to protect both structures 340 * using the same generation count, and also eliminates the overhead 341 * of allocating tcpcbs separately. By hiding the structure here, 342 * we avoid changing most of the rest of the code (although it needs 343 * to be changed, eventually, for greater efficiency). 344 */ 345 #define ALIGNMENT 32 346 #define ALIGNM1 (ALIGNMENT - 1) 347 struct inp_tp { 348 union { 349 struct inpcb inp; 350 char align[(sizeof(struct inpcb) + ALIGNM1) & ~ALIGNM1]; 351 } inp_tp_u; 352 struct tcpcb tcb; 353 struct tcp_callout inp_tp_rexmt; 354 struct tcp_callout inp_tp_persist; 355 struct tcp_callout inp_tp_keep; 356 struct tcp_callout inp_tp_2msl; 357 struct tcp_callout inp_tp_delack; 358 struct netmsg_tcp_timer inp_tp_timermsg; 359 struct netmsg_base inp_tp_sndmore; 360 }; 361 #undef ALIGNMENT 362 #undef ALIGNM1 363 364 /* 365 * Tcp initialization 366 */ 367 void 368 tcp_init(void) 369 { 370 struct inpcbportinfo *portinfo; 371 struct inpcbinfo *ticb; 372 int hashsize = TCBHASHSIZE; 373 int cpu; 374 375 /* 376 * note: tcptemp is used for keepalives, and it is ok for an 377 * allocation to fail so do not specify MPF_INT. 378 */ 379 mpipe_init(&tcptemp_mpipe, M_TCPTEMP, sizeof(struct tcptemp), 380 25, -1, 0, NULL, NULL, NULL); 381 382 tcp_delacktime = TCPTV_DELACK; 383 tcp_keepinit = TCPTV_KEEP_INIT; 384 tcp_keepidle = TCPTV_KEEP_IDLE; 385 tcp_keepintvl = TCPTV_KEEPINTVL; 386 tcp_maxpersistidle = TCPTV_KEEP_IDLE; 387 tcp_msl = TCPTV_MSL; 388 tcp_rexmit_min = TCPTV_MIN; 389 if (tcp_rexmit_min < 1) /* if kern.hz is too low */ 390 tcp_rexmit_min = 1; 391 tcp_rexmit_slop = TCPTV_CPU_VAR; 392 393 TUNABLE_INT_FETCH("net.inet.tcp.tcbhashsize", &hashsize); 394 if (!powerof2(hashsize)) { 395 kprintf("WARNING: TCB hash size not a power of 2\n"); 396 hashsize = 512; /* safe default */ 397 } 398 tcp_tcbhashsize = hashsize; 399 400 portinfo = kmalloc_cachealign(sizeof(*portinfo) * netisr_ncpus, M_PCB, 401 M_WAITOK); 402 403 for (cpu = 0; cpu < netisr_ncpus; cpu++) { 404 ticb = &tcbinfo[cpu]; 405 in_pcbinfo_init(ticb, cpu, FALSE); 406 ticb->hashbase = hashinit(hashsize, M_PCB, 407 &ticb->hashmask); 408 in_pcbportinfo_init(&portinfo[cpu], hashsize, cpu); 409 in_pcbportinfo_set(ticb, portinfo, netisr_ncpus); 410 ticb->wildcardhashbase = hashinit(hashsize, M_PCB, 411 &ticb->wildcardhashmask); 412 ticb->localgrphashbase = hashinit(hashsize, M_PCB, 413 &ticb->localgrphashmask); 414 ticb->ipi_size = sizeof(struct inp_tp); 415 TAILQ_INIT(&tcpcbackq[cpu].head); 416 } 417 418 tcp_reass_maxseg = nmbclusters / 16; 419 TUNABLE_INT_FETCH("net.inet.tcp.reass.maxsegments", &tcp_reass_maxseg); 420 421 #ifdef INET6 422 #define TCP_MINPROTOHDR (sizeof(struct ip6_hdr) + sizeof(struct tcphdr)) 423 #else 424 #define TCP_MINPROTOHDR (sizeof(struct tcpiphdr)) 425 #endif 426 if (max_protohdr < TCP_MINPROTOHDR) 427 max_protohdr = TCP_MINPROTOHDR; 428 if (max_linkhdr + TCP_MINPROTOHDR > MHLEN) 429 panic("tcp_init"); 430 #undef TCP_MINPROTOHDR 431 432 /* 433 * Initialize TCP statistics counters for each CPU. 434 */ 435 for (cpu = 0; cpu < netisr_ncpus; ++cpu) 436 bzero(&tcpstats_percpu[cpu], sizeof(struct tcp_stats)); 437 438 /* 439 * Initialize netmsgs for TCP drain 440 */ 441 for (cpu = 0; cpu < netisr_ncpus; ++cpu) { 442 netmsg_init(&tcp_reassq[cpu].drain_nmsg, NULL, 443 &netisr_adone_rport, MSGF_PRIORITY, tcp_drain_dispatch); 444 } 445 446 syncache_init(); 447 netisr_register_rollup(tcp_willblock, NETISR_ROLLUP_PRIO_TCP); 448 } 449 450 static void 451 tcp_willblock(void) 452 { 453 struct tcpcb *tp; 454 int cpu = mycpuid; 455 456 while ((tp = TAILQ_FIRST(&tcpcbackq[cpu].head)) != NULL) { 457 KKASSERT(tp->t_flags & TF_ONOUTPUTQ); 458 tp->t_flags &= ~TF_ONOUTPUTQ; 459 TAILQ_REMOVE(&tcpcbackq[cpu].head, tp, t_outputq); 460 tcp_output(tp); 461 } 462 } 463 464 /* 465 * Fill in the IP and TCP headers for an outgoing packet, given the tcpcb. 466 * tcp_template used to store this data in mbufs, but we now recopy it out 467 * of the tcpcb each time to conserve mbufs. 468 */ 469 void 470 tcp_fillheaders(struct tcpcb *tp, void *ip_ptr, void *tcp_ptr, boolean_t tso) 471 { 472 struct inpcb *inp = tp->t_inpcb; 473 struct tcphdr *tcp_hdr = (struct tcphdr *)tcp_ptr; 474 475 #ifdef INET6 476 if (INP_ISIPV6(inp)) { 477 struct ip6_hdr *ip6; 478 479 ip6 = (struct ip6_hdr *)ip_ptr; 480 ip6->ip6_flow = (ip6->ip6_flow & ~IPV6_FLOWINFO_MASK) | 481 (inp->in6p_flowinfo & IPV6_FLOWINFO_MASK); 482 ip6->ip6_vfc = (ip6->ip6_vfc & ~IPV6_VERSION_MASK) | 483 (IPV6_VERSION & IPV6_VERSION_MASK); 484 ip6->ip6_nxt = IPPROTO_TCP; 485 ip6->ip6_plen = sizeof(struct tcphdr); 486 ip6->ip6_src = inp->in6p_laddr; 487 ip6->ip6_dst = inp->in6p_faddr; 488 tcp_hdr->th_sum = 0; 489 } else 490 #endif 491 { 492 struct ip *ip = (struct ip *) ip_ptr; 493 u_int plen; 494 495 ip->ip_vhl = IP_VHL_BORING; 496 ip->ip_tos = 0; 497 ip->ip_len = 0; 498 ip->ip_id = 0; 499 ip->ip_off = 0; 500 ip->ip_ttl = 0; 501 ip->ip_sum = 0; 502 ip->ip_p = IPPROTO_TCP; 503 ip->ip_src = inp->inp_laddr; 504 ip->ip_dst = inp->inp_faddr; 505 506 if (tso) 507 plen = htons(IPPROTO_TCP); 508 else 509 plen = htons(sizeof(struct tcphdr) + IPPROTO_TCP); 510 tcp_hdr->th_sum = in_pseudo(ip->ip_src.s_addr, 511 ip->ip_dst.s_addr, plen); 512 } 513 514 tcp_hdr->th_sport = inp->inp_lport; 515 tcp_hdr->th_dport = inp->inp_fport; 516 tcp_hdr->th_seq = 0; 517 tcp_hdr->th_ack = 0; 518 tcp_hdr->th_x2 = 0; 519 tcp_hdr->th_off = 5; 520 tcp_hdr->th_flags = 0; 521 tcp_hdr->th_win = 0; 522 tcp_hdr->th_urp = 0; 523 } 524 525 /* 526 * Create template to be used to send tcp packets on a connection. 527 * Allocates an mbuf and fills in a skeletal tcp/ip header. The only 528 * use for this function is in keepalives, which use tcp_respond. 529 */ 530 struct tcptemp * 531 tcp_maketemplate(struct tcpcb *tp) 532 { 533 struct tcptemp *tmp; 534 535 if ((tmp = mpipe_alloc_nowait(&tcptemp_mpipe)) == NULL) 536 return (NULL); 537 tcp_fillheaders(tp, &tmp->tt_ipgen, &tmp->tt_t, FALSE); 538 return (tmp); 539 } 540 541 void 542 tcp_freetemplate(struct tcptemp *tmp) 543 { 544 mpipe_free(&tcptemp_mpipe, tmp); 545 } 546 547 /* 548 * Send a single message to the TCP at address specified by 549 * the given TCP/IP header. If m == NULL, then we make a copy 550 * of the tcpiphdr at ti and send directly to the addressed host. 551 * This is used to force keep alive messages out using the TCP 552 * template for a connection. If flags are given then we send 553 * a message back to the TCP which originated the * segment ti, 554 * and discard the mbuf containing it and any other attached mbufs. 555 * 556 * In any case the ack and sequence number of the transmitted 557 * segment are as specified by the parameters. 558 * 559 * NOTE: If m != NULL, then ti must point to *inside* the mbuf. 560 */ 561 void 562 tcp_respond(struct tcpcb *tp, void *ipgen, struct tcphdr *th, struct mbuf *m, 563 tcp_seq ack, tcp_seq seq, int flags) 564 { 565 int tlen; 566 long win = 0; 567 struct route *ro = NULL; 568 struct route sro; 569 struct ip *ip = ipgen; 570 struct tcphdr *nth; 571 int ipflags = 0; 572 struct route_in6 *ro6 = NULL; 573 struct route_in6 sro6; 574 struct ip6_hdr *ip6 = ipgen; 575 struct inpcb *inp = NULL; 576 boolean_t use_tmpro = TRUE; 577 #ifdef INET6 578 boolean_t isipv6 = (IP_VHL_V(ip->ip_vhl) == 6); 579 #else 580 const boolean_t isipv6 = FALSE; 581 #endif 582 583 if (tp != NULL) { 584 inp = tp->t_inpcb; 585 if (!(flags & TH_RST)) { 586 win = ssb_space(&inp->inp_socket->so_rcv); 587 if (win < 0) 588 win = 0; 589 if (win > (long)TCP_MAXWIN << tp->rcv_scale) 590 win = (long)TCP_MAXWIN << tp->rcv_scale; 591 } 592 /* 593 * Don't use the route cache of a listen socket, 594 * it is not MPSAFE; use temporary route cache. 595 */ 596 if (tp->t_state != TCPS_LISTEN) { 597 if (isipv6) 598 ro6 = &inp->in6p_route; 599 else 600 ro = &inp->inp_route; 601 use_tmpro = FALSE; 602 } 603 } 604 if (use_tmpro) { 605 if (isipv6) { 606 ro6 = &sro6; 607 bzero(ro6, sizeof *ro6); 608 } else { 609 ro = &sro; 610 bzero(ro, sizeof *ro); 611 } 612 } 613 if (m == NULL) { 614 m = m_gethdr(M_NOWAIT, MT_HEADER); 615 if (m == NULL) 616 return; 617 tlen = 0; 618 m->m_data += max_linkhdr; 619 if (isipv6) { 620 bcopy(ip6, mtod(m, caddr_t), sizeof(struct ip6_hdr)); 621 ip6 = mtod(m, struct ip6_hdr *); 622 nth = (struct tcphdr *)(ip6 + 1); 623 } else { 624 bcopy(ip, mtod(m, caddr_t), sizeof(struct ip)); 625 ip = mtod(m, struct ip *); 626 nth = (struct tcphdr *)(ip + 1); 627 } 628 bcopy(th, nth, sizeof(struct tcphdr)); 629 flags = TH_ACK; 630 } else { 631 m_freem(m->m_next); 632 m->m_next = NULL; 633 m->m_data = (caddr_t)ipgen; 634 /* m_len is set later */ 635 tlen = 0; 636 #define xchg(a, b, type) { type t; t = a; a = b; b = t; } 637 if (isipv6) { 638 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); 639 nth = (struct tcphdr *)(ip6 + 1); 640 } else { 641 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, n_long); 642 nth = (struct tcphdr *)(ip + 1); 643 } 644 if (th != nth) { 645 /* 646 * this is usually a case when an extension header 647 * exists between the IPv6 header and the 648 * TCP header. 649 */ 650 nth->th_sport = th->th_sport; 651 nth->th_dport = th->th_dport; 652 } 653 xchg(nth->th_dport, nth->th_sport, n_short); 654 #undef xchg 655 } 656 if (isipv6) { 657 ip6->ip6_flow = 0; 658 ip6->ip6_vfc = IPV6_VERSION; 659 ip6->ip6_nxt = IPPROTO_TCP; 660 ip6->ip6_plen = htons((u_short)(sizeof(struct tcphdr) + tlen)); 661 tlen += sizeof(struct ip6_hdr) + sizeof(struct tcphdr); 662 } else { 663 tlen += sizeof(struct tcpiphdr); 664 ip->ip_len = tlen; 665 ip->ip_ttl = ip_defttl; 666 } 667 m->m_len = tlen; 668 m->m_pkthdr.len = tlen; 669 m->m_pkthdr.rcvif = NULL; 670 nth->th_seq = htonl(seq); 671 nth->th_ack = htonl(ack); 672 nth->th_x2 = 0; 673 nth->th_off = sizeof(struct tcphdr) >> 2; 674 nth->th_flags = flags; 675 if (tp != NULL) 676 nth->th_win = htons((u_short) (win >> tp->rcv_scale)); 677 else 678 nth->th_win = htons((u_short)win); 679 nth->th_urp = 0; 680 if (isipv6) { 681 nth->th_sum = 0; 682 nth->th_sum = in6_cksum(m, IPPROTO_TCP, 683 sizeof(struct ip6_hdr), 684 tlen - sizeof(struct ip6_hdr)); 685 ip6->ip6_hlim = in6_selecthlim(inp, 686 (ro6 && ro6->ro_rt) ? ro6->ro_rt->rt_ifp : NULL); 687 } else { 688 nth->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, 689 htons((u_short)(tlen - sizeof(struct ip) + ip->ip_p))); 690 m->m_pkthdr.csum_flags = CSUM_TCP; 691 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); 692 m->m_pkthdr.csum_thlen = sizeof(struct tcphdr); 693 } 694 #ifdef TCPDEBUG 695 if (tp == NULL || (inp->inp_socket->so_options & SO_DEBUG)) 696 tcp_trace(TA_OUTPUT, 0, tp, mtod(m, void *), th, 0); 697 #endif 698 if (isipv6) { 699 ip6_output(m, NULL, ro6, ipflags, NULL, NULL, inp); 700 if ((ro6 == &sro6) && (ro6->ro_rt != NULL)) { 701 RTFREE(ro6->ro_rt); 702 ro6->ro_rt = NULL; 703 } 704 } else { 705 if (inp != NULL && (inp->inp_flags & INP_HASH)) 706 m_sethash(m, inp->inp_hashval); 707 ipflags |= IP_DEBUGROUTE; 708 ip_output(m, NULL, ro, ipflags, NULL, inp); 709 if ((ro == &sro) && (ro->ro_rt != NULL)) { 710 RTFREE(ro->ro_rt); 711 ro->ro_rt = NULL; 712 } 713 } 714 } 715 716 /* 717 * Create a new TCP control block, making an 718 * empty reassembly queue and hooking it to the argument 719 * protocol control block. The `inp' parameter must have 720 * come from the zone allocator set up in tcp_init(). 721 */ 722 void 723 tcp_newtcpcb(struct inpcb *inp) 724 { 725 struct inp_tp *it; 726 struct tcpcb *tp; 727 #ifdef INET6 728 boolean_t isipv6 = INP_ISIPV6(inp); 729 #else 730 const boolean_t isipv6 = FALSE; 731 #endif 732 733 it = (struct inp_tp *)inp; 734 tp = &it->tcb; 735 bzero(tp, sizeof(struct tcpcb)); 736 TAILQ_INIT(&tp->t_segq); 737 tp->t_maxseg = tp->t_maxopd = isipv6 ? tcp_v6mssdflt : tcp_mssdflt; 738 tp->t_rxtthresh = tcprexmtthresh; 739 740 /* Set up our timeouts. */ 741 tp->tt_rexmt = &it->inp_tp_rexmt; 742 tp->tt_persist = &it->inp_tp_persist; 743 tp->tt_keep = &it->inp_tp_keep; 744 tp->tt_2msl = &it->inp_tp_2msl; 745 tp->tt_delack = &it->inp_tp_delack; 746 tcp_inittimers(tp); 747 748 /* 749 * Zero out timer message. We don't create it here, 750 * since the current CPU may not be the owner of this 751 * inpcb. 752 */ 753 tp->tt_msg = &it->inp_tp_timermsg; 754 bzero(tp->tt_msg, sizeof(*tp->tt_msg)); 755 756 tp->t_keepinit = tcp_keepinit; 757 tp->t_keepidle = tcp_keepidle; 758 tp->t_keepintvl = tcp_keepintvl; 759 tp->t_keepcnt = tcp_keepcnt; 760 tp->t_maxidle = tp->t_keepintvl * tp->t_keepcnt; 761 762 if (tcp_do_ncr) 763 tp->t_flags |= TF_NCR; 764 if (tcp_do_rfc1323) 765 tp->t_flags |= (TF_REQ_SCALE | TF_REQ_TSTMP); 766 767 tp->t_inpcb = inp; /* XXX */ 768 TCP_STATE_INIT(tp); 769 /* 770 * Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no 771 * rtt estimate. Set rttvar so that srtt + 4 * rttvar gives 772 * reasonable initial retransmit time. 773 */ 774 tp->t_srtt = TCPTV_SRTTBASE; 775 tp->t_rttvar = 776 ((TCPTV_RTOBASE - TCPTV_SRTTBASE) << TCP_RTTVAR_SHIFT) / 4; 777 tp->t_rttmin = tcp_rexmit_min; 778 tp->t_rxtcur = TCPTV_RTOBASE; 779 tp->snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT; 780 tp->snd_bwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT; 781 tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT; 782 tp->snd_last = ticks; 783 tp->t_rcvtime = ticks; 784 /* 785 * IPv4 TTL initialization is necessary for an IPv6 socket as well, 786 * because the socket may be bound to an IPv6 wildcard address, 787 * which may match an IPv4-mapped IPv6 address. 788 */ 789 inp->inp_ip_ttl = ip_defttl; 790 inp->inp_ppcb = tp; 791 tcp_sack_tcpcb_init(tp); 792 793 tp->tt_sndmore = &it->inp_tp_sndmore; 794 tcp_output_init(tp); 795 } 796 797 /* 798 * Drop a TCP connection, reporting the specified error. 799 * If connection is synchronized, then send a RST to peer. 800 */ 801 struct tcpcb * 802 tcp_drop(struct tcpcb *tp, int error) 803 { 804 struct socket *so = tp->t_inpcb->inp_socket; 805 806 if (TCPS_HAVERCVDSYN(tp->t_state)) { 807 TCP_STATE_CHANGE(tp, TCPS_CLOSED); 808 tcp_output(tp); 809 tcpstat.tcps_drops++; 810 } else 811 tcpstat.tcps_conndrops++; 812 if (error == ETIMEDOUT && tp->t_softerror) 813 error = tp->t_softerror; 814 so->so_error = error; 815 return (tcp_close(tp)); 816 } 817 818 struct netmsg_listen_detach { 819 struct netmsg_base base; 820 struct tcpcb *nm_tp; 821 struct tcpcb *nm_tp_inh; 822 }; 823 824 static void 825 tcp_listen_detach_handler(netmsg_t msg) 826 { 827 struct netmsg_listen_detach *nmsg = (struct netmsg_listen_detach *)msg; 828 struct tcpcb *tp = nmsg->nm_tp; 829 int cpu = mycpuid, nextcpu; 830 831 if (tp->t_flags & TF_LISTEN) { 832 syncache_destroy(tp, nmsg->nm_tp_inh); 833 tcp_pcbport_merge_oncpu(tp); 834 } 835 836 in_pcbremwildcardhash_oncpu(tp->t_inpcb, &tcbinfo[cpu]); 837 838 nextcpu = cpu + 1; 839 if (nextcpu < netisr_ncpus) 840 lwkt_forwardmsg(netisr_cpuport(nextcpu), &nmsg->base.lmsg); 841 else 842 lwkt_replymsg(&nmsg->base.lmsg, 0); 843 } 844 845 /* 846 * Close a TCP control block: 847 * discard all space held by the tcp 848 * discard internet protocol block 849 * wake up any sleepers 850 */ 851 struct tcpcb * 852 tcp_close(struct tcpcb *tp) 853 { 854 struct tseg_qent *q; 855 struct inpcb *inp = tp->t_inpcb; 856 struct inpcb *inp_inh = NULL; 857 struct tcpcb *tp_inh = NULL; 858 struct socket *so = inp->inp_socket; 859 struct rtentry *rt; 860 boolean_t dosavessthresh; 861 #ifdef INET6 862 boolean_t isipv6 = INP_ISIPV6(inp); 863 #else 864 const boolean_t isipv6 = FALSE; 865 #endif 866 867 if (tp->t_flags & TF_LISTEN) { 868 /* 869 * Pending socket/syncache inheritance 870 * 871 * If this is a listen(2) socket, find another listen(2) 872 * socket in the same local group, which could inherit 873 * the syncache and sockets pending on the completion 874 * and incompletion queues. 875 * 876 * NOTE: 877 * Currently the inheritance could only happen on the 878 * listen(2) sockets w/ SO_REUSEPORT set. 879 */ 880 ASSERT_NETISR0; 881 inp_inh = in_pcblocalgroup_last(&tcbinfo[0], inp); 882 if (inp_inh != NULL) 883 tp_inh = intotcpcb(inp_inh); 884 } 885 886 /* 887 * INP_WILDCARD indicates that listen(2) has been called on 888 * this socket. This implies: 889 * - A wildcard inp's hash is replicated for each protocol thread. 890 * - Syncache for this inp grows independently in each protocol 891 * thread. 892 * - There is more than one cpu 893 * 894 * We have to chain a message to the rest of the protocol threads 895 * to cleanup the wildcard hash and the syncache. The cleanup 896 * in the current protocol thread is defered till the end of this 897 * function (syncache_destroy and in_pcbdetach). 898 * 899 * NOTE: 900 * After cleanup the inp's hash and syncache entries, this inp will 901 * no longer be available to the rest of the protocol threads, so we 902 * are safe to whack the inp in the following code. 903 */ 904 if ((inp->inp_flags & INP_WILDCARD) && netisr_ncpus > 1) { 905 struct netmsg_listen_detach nmsg; 906 907 KKASSERT(so->so_port == netisr_cpuport(0)); 908 ASSERT_NETISR0; 909 KKASSERT(inp->inp_pcbinfo == &tcbinfo[0]); 910 911 netmsg_init(&nmsg.base, NULL, &curthread->td_msgport, 912 MSGF_PRIORITY, tcp_listen_detach_handler); 913 nmsg.nm_tp = tp; 914 nmsg.nm_tp_inh = tp_inh; 915 lwkt_domsg(netisr_cpuport(1), &nmsg.base.lmsg, 0); 916 } 917 918 TCP_STATE_TERM(tp); 919 920 /* 921 * Make sure that all of our timers are stopped before we 922 * delete the PCB. For listen TCP socket (tp->tt_msg == NULL), 923 * timers are never used. If timer message is never created 924 * (tp->tt_msg->tt_tcb == NULL), timers are never used too. 925 */ 926 if (tp->tt_msg != NULL && tp->tt_msg->tt_tcb != NULL) { 927 tcp_callout_stop(tp, tp->tt_rexmt); 928 tcp_callout_stop(tp, tp->tt_persist); 929 tcp_callout_stop(tp, tp->tt_keep); 930 tcp_callout_stop(tp, tp->tt_2msl); 931 tcp_callout_stop(tp, tp->tt_delack); 932 } 933 934 if (tp->t_flags & TF_ONOUTPUTQ) { 935 KKASSERT(tp->tt_cpu == mycpu->gd_cpuid); 936 TAILQ_REMOVE(&tcpcbackq[tp->tt_cpu].head, tp, t_outputq); 937 tp->t_flags &= ~TF_ONOUTPUTQ; 938 } 939 940 /* 941 * If we got enough samples through the srtt filter, 942 * save the rtt and rttvar in the routing entry. 943 * 'Enough' is arbitrarily defined as the 16 samples. 944 * 16 samples is enough for the srtt filter to converge 945 * to within 5% of the correct value; fewer samples and 946 * we could save a very bogus rtt. 947 * 948 * Don't update the default route's characteristics and don't 949 * update anything that the user "locked". 950 */ 951 if (tp->t_rttupdated >= 16) { 952 u_long i = 0; 953 954 if (isipv6) { 955 struct sockaddr_in6 *sin6; 956 957 if ((rt = inp->in6p_route.ro_rt) == NULL) 958 goto no_valid_rt; 959 sin6 = (struct sockaddr_in6 *)rt_key(rt); 960 if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) 961 goto no_valid_rt; 962 } else 963 if ((rt = inp->inp_route.ro_rt) == NULL || 964 ((struct sockaddr_in *)rt_key(rt))-> 965 sin_addr.s_addr == INADDR_ANY) 966 goto no_valid_rt; 967 968 if (!(rt->rt_rmx.rmx_locks & RTV_RTT)) { 969 i = tp->t_srtt * (RTM_RTTUNIT / (hz * TCP_RTT_SCALE)); 970 if (rt->rt_rmx.rmx_rtt && i) 971 /* 972 * filter this update to half the old & half 973 * the new values, converting scale. 974 * See route.h and tcp_var.h for a 975 * description of the scaling constants. 976 */ 977 rt->rt_rmx.rmx_rtt = 978 (rt->rt_rmx.rmx_rtt + i) / 2; 979 else 980 rt->rt_rmx.rmx_rtt = i; 981 tcpstat.tcps_cachedrtt++; 982 } 983 if (!(rt->rt_rmx.rmx_locks & RTV_RTTVAR)) { 984 i = tp->t_rttvar * 985 (RTM_RTTUNIT / (hz * TCP_RTTVAR_SCALE)); 986 if (rt->rt_rmx.rmx_rttvar && i) 987 rt->rt_rmx.rmx_rttvar = 988 (rt->rt_rmx.rmx_rttvar + i) / 2; 989 else 990 rt->rt_rmx.rmx_rttvar = i; 991 tcpstat.tcps_cachedrttvar++; 992 } 993 /* 994 * The old comment here said: 995 * update the pipelimit (ssthresh) if it has been updated 996 * already or if a pipesize was specified & the threshhold 997 * got below half the pipesize. I.e., wait for bad news 998 * before we start updating, then update on both good 999 * and bad news. 1000 * 1001 * But we want to save the ssthresh even if no pipesize is 1002 * specified explicitly in the route, because such 1003 * connections still have an implicit pipesize specified 1004 * by the global tcp_sendspace. In the absence of a reliable 1005 * way to calculate the pipesize, it will have to do. 1006 */ 1007 i = tp->snd_ssthresh; 1008 if (rt->rt_rmx.rmx_sendpipe != 0) 1009 dosavessthresh = (i < rt->rt_rmx.rmx_sendpipe/2); 1010 else 1011 dosavessthresh = (i < so->so_snd.ssb_hiwat/2); 1012 if (dosavessthresh || 1013 (!(rt->rt_rmx.rmx_locks & RTV_SSTHRESH) && (i != 0) && 1014 (rt->rt_rmx.rmx_ssthresh != 0))) { 1015 /* 1016 * convert the limit from user data bytes to 1017 * packets then to packet data bytes. 1018 */ 1019 i = (i + tp->t_maxseg / 2) / tp->t_maxseg; 1020 if (i < 2) 1021 i = 2; 1022 i *= tp->t_maxseg + 1023 (isipv6 ? 1024 sizeof(struct ip6_hdr) + sizeof(struct tcphdr) : 1025 sizeof(struct tcpiphdr)); 1026 if (rt->rt_rmx.rmx_ssthresh) 1027 rt->rt_rmx.rmx_ssthresh = 1028 (rt->rt_rmx.rmx_ssthresh + i) / 2; 1029 else 1030 rt->rt_rmx.rmx_ssthresh = i; 1031 tcpstat.tcps_cachedssthresh++; 1032 } 1033 } 1034 1035 no_valid_rt: 1036 /* free the reassembly queue, if any */ 1037 while((q = TAILQ_FIRST(&tp->t_segq)) != NULL) { 1038 TAILQ_REMOVE(&tp->t_segq, q, tqe_q); 1039 m_freem(q->tqe_m); 1040 kfree(q, M_TSEGQ); 1041 atomic_add_int(&tcp_reass_qsize, -1); 1042 } 1043 /* throw away SACK blocks in scoreboard*/ 1044 if (TCP_DO_SACK(tp)) 1045 tcp_sack_destroy(&tp->scb); 1046 1047 inp->inp_ppcb = NULL; 1048 soisdisconnected(so); 1049 /* note: pcb detached later on */ 1050 1051 tcp_destroy_timermsg(tp); 1052 tcp_output_cancel(tp); 1053 1054 if (tp->t_flags & TF_LISTEN) { 1055 syncache_destroy(tp, tp_inh); 1056 tcp_pcbport_merge_oncpu(tp); 1057 tcp_pcbport_destroy(tp); 1058 if (inp_inh != NULL && inp_inh->inp_socket != NULL) { 1059 /* 1060 * Pending sockets inheritance only needs 1061 * to be done once in the current thread, 1062 * i.e. netisr0. 1063 */ 1064 soinherit(so, inp_inh->inp_socket); 1065 } 1066 } 1067 KASSERT(tp->t_pcbport == NULL, ("tcpcb port cache is not destroyed")); 1068 1069 so_async_rcvd_drop(so); 1070 /* Drop the reference for the asynchronized pru_rcvd */ 1071 sofree(so); 1072 1073 /* 1074 * NOTE: 1075 * - Remove self from listen tcpcb per-cpu port cache _before_ 1076 * pcbdetach. 1077 * - pcbdetach removes any wildcard hash entry on the current CPU. 1078 */ 1079 tcp_pcbport_remove(inp); 1080 #ifdef INET6 1081 if (isipv6) 1082 in6_pcbdetach(inp); 1083 else 1084 #endif 1085 in_pcbdetach(inp); 1086 1087 tcpstat.tcps_closed++; 1088 return (NULL); 1089 } 1090 1091 /* 1092 * Walk the tcpbs, if existing, and flush the reassembly queue, 1093 * if there is one... 1094 */ 1095 static void 1096 tcp_drain_oncpu(struct inpcbinfo *pcbinfo) 1097 { 1098 struct inpcbhead *head = &pcbinfo->pcblisthead; 1099 struct inpcb *inpb; 1100 1101 /* 1102 * Since we run in netisr, it is MP safe, even if 1103 * we block during the inpcb list iteration, i.e. 1104 * we don't need to use inpcb marker here. 1105 */ 1106 ASSERT_NETISR_NCPUS(pcbinfo->cpu); 1107 1108 LIST_FOREACH(inpb, head, inp_list) { 1109 struct tcpcb *tcpb; 1110 struct tseg_qent *te; 1111 1112 if (inpb->inp_flags & INP_PLACEMARKER) 1113 continue; 1114 1115 tcpb = intotcpcb(inpb); 1116 KASSERT(tcpb != NULL, ("tcp_drain_oncpu: tcpb is NULL")); 1117 1118 if ((te = TAILQ_FIRST(&tcpb->t_segq)) != NULL) { 1119 TAILQ_REMOVE(&tcpb->t_segq, te, tqe_q); 1120 if (te->tqe_th->th_flags & TH_FIN) 1121 tcpb->t_flags &= ~TF_QUEDFIN; 1122 m_freem(te->tqe_m); 1123 kfree(te, M_TSEGQ); 1124 atomic_add_int(&tcp_reass_qsize, -1); 1125 /* retry */ 1126 } 1127 } 1128 } 1129 1130 static void 1131 tcp_drain_dispatch(netmsg_t nmsg) 1132 { 1133 crit_enter(); 1134 lwkt_replymsg(&nmsg->lmsg, 0); /* reply ASAP */ 1135 crit_exit(); 1136 1137 tcp_drain_oncpu(&tcbinfo[mycpuid]); 1138 tcp_reassq[mycpuid].draining = 0; 1139 } 1140 1141 static void 1142 tcp_drain_ipi(void *arg __unused) 1143 { 1144 int cpu = mycpuid; 1145 struct lwkt_msg *msg = &tcp_reassq[cpu].drain_nmsg.lmsg; 1146 1147 crit_enter(); 1148 if (msg->ms_flags & MSGF_DONE) 1149 lwkt_sendmsg_oncpu(netisr_cpuport(cpu), msg); 1150 crit_exit(); 1151 } 1152 1153 void 1154 tcp_drain(void) 1155 { 1156 cpumask_t mask; 1157 int cpu; 1158 1159 if (!do_tcpdrain) 1160 return; 1161 1162 if (tcp_reass_qsize == 0) 1163 return; 1164 1165 CPUMASK_ASSBMASK(mask, netisr_ncpus); 1166 CPUMASK_ANDMASK(mask, smp_active_mask); 1167 1168 cpu = mycpuid; 1169 if (IN_NETISR_NCPUS(cpu)) { 1170 tcp_drain_oncpu(&tcbinfo[cpu]); 1171 CPUMASK_NANDBIT(mask, cpu); 1172 } 1173 1174 if (tcp_reass_qsize < netisr_ncpus) { 1175 /* Does not worth the trouble. */ 1176 return; 1177 } 1178 1179 for (cpu = 0; cpu < netisr_ncpus; ++cpu) { 1180 if (!CPUMASK_TESTBIT(mask, cpu)) 1181 continue; 1182 1183 if (tcp_reassq[cpu].draining) { 1184 /* Draining; skip this cpu. */ 1185 CPUMASK_NANDBIT(mask, cpu); 1186 continue; 1187 } 1188 tcp_reassq[cpu].draining = 1; 1189 } 1190 1191 if (CPUMASK_TESTNZERO(mask)) 1192 lwkt_send_ipiq_mask(mask, tcp_drain_ipi, NULL); 1193 } 1194 1195 /* 1196 * Notify a tcp user of an asynchronous error; 1197 * store error as soft error, but wake up user 1198 * (for now, won't do anything until can select for soft error). 1199 * 1200 * Do not wake up user since there currently is no mechanism for 1201 * reporting soft errors (yet - a kqueue filter may be added). 1202 */ 1203 static void 1204 tcp_notify(struct inpcb *inp, int error) 1205 { 1206 struct tcpcb *tp = intotcpcb(inp); 1207 1208 /* 1209 * Ignore some errors if we are hooked up. 1210 * If connection hasn't completed, has retransmitted several times, 1211 * and receives a second error, give up now. This is better 1212 * than waiting a long time to establish a connection that 1213 * can never complete. 1214 */ 1215 if (tp->t_state == TCPS_ESTABLISHED && 1216 (error == EHOSTUNREACH || error == ENETUNREACH || 1217 error == EHOSTDOWN)) { 1218 return; 1219 } else if (tp->t_state < TCPS_ESTABLISHED && tp->t_rxtshift > 3 && 1220 tp->t_softerror) 1221 tcp_drop(tp, error); 1222 else 1223 tp->t_softerror = error; 1224 #if 0 1225 wakeup(&so->so_timeo); 1226 sorwakeup(so); 1227 sowwakeup(so); 1228 #endif 1229 } 1230 1231 static int 1232 tcp_pcblist(SYSCTL_HANDLER_ARGS) 1233 { 1234 int error, i, n; 1235 struct inpcb *marker; 1236 struct inpcb *inp; 1237 int origcpu, ccpu; 1238 1239 error = 0; 1240 n = 0; 1241 1242 /* 1243 * The process of preparing the TCB list is too time-consuming and 1244 * resource-intensive to repeat twice on every request. 1245 */ 1246 if (req->oldptr == NULL) { 1247 for (ccpu = 0; ccpu < netisr_ncpus; ++ccpu) 1248 n += tcbinfo[ccpu].ipi_count; 1249 req->oldidx = (n + n/8 + 10) * sizeof(struct xtcpcb); 1250 return (0); 1251 } 1252 1253 if (req->newptr != NULL) 1254 return (EPERM); 1255 1256 marker = kmalloc(sizeof(struct inpcb), M_TEMP, M_WAITOK|M_ZERO); 1257 marker->inp_flags |= INP_PLACEMARKER; 1258 1259 /* 1260 * OK, now we're committed to doing something. Run the inpcb list 1261 * for each cpu in the system and construct the output. Use a 1262 * list placemarker to deal with list changes occuring during 1263 * copyout blockages (but otherwise depend on being on the correct 1264 * cpu to avoid races). 1265 */ 1266 origcpu = mycpu->gd_cpuid; 1267 for (ccpu = 0; ccpu < netisr_ncpus && error == 0; ++ccpu) { 1268 caddr_t inp_ppcb; 1269 struct xtcpcb xt; 1270 1271 lwkt_migratecpu(ccpu); 1272 1273 n = tcbinfo[ccpu].ipi_count; 1274 1275 LIST_INSERT_HEAD(&tcbinfo[ccpu].pcblisthead, marker, inp_list); 1276 i = 0; 1277 while ((inp = LIST_NEXT(marker, inp_list)) != NULL && i < n) { 1278 /* 1279 * process a snapshot of pcbs, ignoring placemarkers 1280 * and using our own to allow SYSCTL_OUT to block. 1281 */ 1282 LIST_REMOVE(marker, inp_list); 1283 LIST_INSERT_AFTER(inp, marker, inp_list); 1284 1285 if (inp->inp_flags & INP_PLACEMARKER) 1286 continue; 1287 if (prison_xinpcb(req->td, inp)) 1288 continue; 1289 1290 xt.xt_len = sizeof xt; 1291 bcopy(inp, &xt.xt_inp, sizeof *inp); 1292 inp_ppcb = inp->inp_ppcb; 1293 if (inp_ppcb != NULL) 1294 bcopy(inp_ppcb, &xt.xt_tp, sizeof xt.xt_tp); 1295 else 1296 bzero(&xt.xt_tp, sizeof xt.xt_tp); 1297 if (inp->inp_socket) 1298 sotoxsocket(inp->inp_socket, &xt.xt_socket); 1299 if ((error = SYSCTL_OUT(req, &xt, sizeof xt)) != 0) 1300 break; 1301 ++i; 1302 } 1303 LIST_REMOVE(marker, inp_list); 1304 if (error == 0 && i < n) { 1305 bzero(&xt, sizeof xt); 1306 xt.xt_len = sizeof xt; 1307 while (i < n) { 1308 error = SYSCTL_OUT(req, &xt, sizeof xt); 1309 if (error) 1310 break; 1311 ++i; 1312 } 1313 } 1314 } 1315 1316 /* 1317 * Make sure we are on the same cpu we were on originally, since 1318 * higher level callers expect this. Also don't pollute caches with 1319 * migrated userland data by (eventually) returning to userland 1320 * on a different cpu. 1321 */ 1322 lwkt_migratecpu(origcpu); 1323 kfree(marker, M_TEMP); 1324 return (error); 1325 } 1326 1327 SYSCTL_PROC(_net_inet_tcp, TCPCTL_PCBLIST, pcblist, CTLFLAG_RD, 0, 0, 1328 tcp_pcblist, "S,xtcpcb", "List of active TCP connections"); 1329 1330 static int 1331 tcp_getcred(SYSCTL_HANDLER_ARGS) 1332 { 1333 struct sockaddr_in addrs[2]; 1334 struct ucred cred0, *cred = NULL; 1335 struct inpcb *inp; 1336 int cpu, origcpu, error; 1337 1338 error = priv_check(req->td, PRIV_ROOT); 1339 if (error != 0) 1340 return (error); 1341 error = SYSCTL_IN(req, addrs, sizeof addrs); 1342 if (error != 0) 1343 return (error); 1344 1345 origcpu = mycpuid; 1346 cpu = tcp_addrcpu(addrs[1].sin_addr.s_addr, addrs[1].sin_port, 1347 addrs[0].sin_addr.s_addr, addrs[0].sin_port); 1348 1349 lwkt_migratecpu(cpu); 1350 1351 inp = in_pcblookup_hash(&tcbinfo[cpu], addrs[1].sin_addr, 1352 addrs[1].sin_port, addrs[0].sin_addr, addrs[0].sin_port, 0, NULL); 1353 if (inp == NULL || inp->inp_socket == NULL) { 1354 error = ENOENT; 1355 } else if (inp->inp_socket->so_cred != NULL) { 1356 cred0 = *(inp->inp_socket->so_cred); 1357 cred = &cred0; 1358 } 1359 1360 lwkt_migratecpu(origcpu); 1361 1362 if (error) 1363 return (error); 1364 1365 return SYSCTL_OUT(req, cred, sizeof(struct ucred)); 1366 } 1367 1368 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, getcred, (CTLTYPE_OPAQUE | CTLFLAG_RW), 1369 0, 0, tcp_getcred, "S,ucred", "Get the ucred of a TCP connection"); 1370 1371 #ifdef INET6 1372 static int 1373 tcp6_getcred(SYSCTL_HANDLER_ARGS) 1374 { 1375 struct sockaddr_in6 addrs[2]; 1376 struct inpcb *inp; 1377 int error; 1378 1379 error = priv_check(req->td, PRIV_ROOT); 1380 if (error != 0) 1381 return (error); 1382 error = SYSCTL_IN(req, addrs, sizeof addrs); 1383 if (error != 0) 1384 return (error); 1385 crit_enter(); 1386 inp = in6_pcblookup_hash(&tcbinfo[0], 1387 &addrs[1].sin6_addr, addrs[1].sin6_port, 1388 &addrs[0].sin6_addr, addrs[0].sin6_port, 0, NULL); 1389 if (inp == NULL || inp->inp_socket == NULL) { 1390 error = ENOENT; 1391 goto out; 1392 } 1393 error = SYSCTL_OUT(req, inp->inp_socket->so_cred, sizeof(struct ucred)); 1394 out: 1395 crit_exit(); 1396 return (error); 1397 } 1398 1399 SYSCTL_PROC(_net_inet6_tcp6, OID_AUTO, getcred, (CTLTYPE_OPAQUE | CTLFLAG_RW), 1400 0, 0, 1401 tcp6_getcred, "S,ucred", "Get the ucred of a TCP6 connection"); 1402 #endif 1403 1404 struct netmsg_tcp_notify { 1405 struct netmsg_base base; 1406 inp_notify_t nm_notify; 1407 struct in_addr nm_faddr; 1408 int nm_arg; 1409 }; 1410 1411 static void 1412 tcp_notifyall_oncpu(netmsg_t msg) 1413 { 1414 struct netmsg_tcp_notify *nm = (struct netmsg_tcp_notify *)msg; 1415 int nextcpu; 1416 1417 ASSERT_NETISR_NCPUS(mycpuid); 1418 1419 in_pcbnotifyall(&tcbinfo[mycpuid], nm->nm_faddr, 1420 nm->nm_arg, nm->nm_notify); 1421 1422 nextcpu = mycpuid + 1; 1423 if (nextcpu < netisr_ncpus) 1424 lwkt_forwardmsg(netisr_cpuport(nextcpu), &nm->base.lmsg); 1425 else 1426 lwkt_replymsg(&nm->base.lmsg, 0); 1427 } 1428 1429 inp_notify_t 1430 tcp_get_inpnotify(int cmd, const struct sockaddr *sa, 1431 int *arg, struct ip **ip0, int *cpuid) 1432 { 1433 struct ip *ip = *ip0; 1434 struct in_addr faddr; 1435 inp_notify_t notify = tcp_notify; 1436 1437 faddr = ((const struct sockaddr_in *)sa)->sin_addr; 1438 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY) 1439 return NULL; 1440 1441 *arg = inetctlerrmap[cmd]; 1442 if (cmd == PRC_QUENCH) { 1443 notify = tcp_quench; 1444 } else if (icmp_may_rst && 1445 (cmd == PRC_UNREACH_ADMIN_PROHIB || 1446 cmd == PRC_UNREACH_PORT || 1447 cmd == PRC_TIMXCEED_INTRANS) && 1448 ip != NULL) { 1449 notify = tcp_drop_syn_sent; 1450 } else if (cmd == PRC_MSGSIZE) { 1451 const struct icmp *icmp = (const struct icmp *) 1452 ((caddr_t)ip - offsetof(struct icmp, icmp_ip)); 1453 1454 *arg = ntohs(icmp->icmp_nextmtu); 1455 notify = tcp_mtudisc; 1456 } else if (PRC_IS_REDIRECT(cmd)) { 1457 ip = NULL; 1458 notify = in_rtchange; 1459 } else if (cmd == PRC_HOSTDEAD) { 1460 ip = NULL; 1461 } else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0) { 1462 return NULL; 1463 } 1464 1465 if (cpuid != NULL) { 1466 if (ip == NULL) { 1467 /* Go through all effective netisr CPUs. */ 1468 *cpuid = netisr_ncpus; 1469 } else { 1470 const struct tcphdr *th; 1471 1472 th = (const struct tcphdr *) 1473 ((caddr_t)ip + (IP_VHL_HL(ip->ip_vhl) << 2)); 1474 *cpuid = tcp_addrcpu(faddr.s_addr, th->th_dport, 1475 ip->ip_src.s_addr, th->th_sport); 1476 } 1477 } 1478 1479 *ip0 = ip; 1480 return notify; 1481 } 1482 1483 void 1484 tcp_ctlinput(netmsg_t msg) 1485 { 1486 int cmd = msg->ctlinput.nm_cmd; 1487 struct sockaddr *sa = msg->ctlinput.nm_arg; 1488 struct ip *ip = msg->ctlinput.nm_extra; 1489 struct in_addr faddr; 1490 inp_notify_t notify; 1491 int arg, cpuid; 1492 1493 ASSERT_NETISR_NCPUS(mycpuid); 1494 1495 notify = tcp_get_inpnotify(cmd, sa, &arg, &ip, &cpuid); 1496 if (notify == NULL) 1497 goto done; 1498 1499 faddr = ((struct sockaddr_in *)sa)->sin_addr; 1500 if (ip != NULL) { 1501 const struct tcphdr *th; 1502 struct inpcb *inp; 1503 1504 if (cpuid != mycpuid) 1505 goto done; 1506 1507 th = (const struct tcphdr *) 1508 ((caddr_t)ip + (IP_VHL_HL(ip->ip_vhl) << 2)); 1509 inp = in_pcblookup_hash(&tcbinfo[mycpuid], faddr, th->th_dport, 1510 ip->ip_src, th->th_sport, 0, NULL); 1511 if (inp != NULL && inp->inp_socket != NULL) { 1512 tcp_seq icmpseq = htonl(th->th_seq); 1513 struct tcpcb *tp = intotcpcb(inp); 1514 1515 if (SEQ_GEQ(icmpseq, tp->snd_una) && 1516 SEQ_LT(icmpseq, tp->snd_max)) 1517 notify(inp, arg); 1518 } else { 1519 struct in_conninfo inc; 1520 1521 inc.inc_fport = th->th_dport; 1522 inc.inc_lport = th->th_sport; 1523 inc.inc_faddr = faddr; 1524 inc.inc_laddr = ip->ip_src; 1525 #ifdef INET6 1526 inc.inc_isipv6 = 0; 1527 #endif 1528 syncache_unreach(&inc, th); 1529 } 1530 } else if (msg->ctlinput.nm_direct) { 1531 if (cpuid != netisr_ncpus && cpuid != mycpuid) 1532 goto done; 1533 1534 in_pcbnotifyall(&tcbinfo[mycpuid], faddr, arg, notify); 1535 } else { 1536 struct netmsg_tcp_notify *nm; 1537 1538 ASSERT_NETISR0; 1539 nm = kmalloc(sizeof(*nm), M_LWKTMSG, M_INTWAIT); 1540 netmsg_init(&nm->base, NULL, &netisr_afree_rport, 1541 0, tcp_notifyall_oncpu); 1542 nm->nm_faddr = faddr; 1543 nm->nm_arg = arg; 1544 nm->nm_notify = notify; 1545 1546 lwkt_sendmsg(netisr_cpuport(0), &nm->base.lmsg); 1547 } 1548 done: 1549 lwkt_replymsg(&msg->lmsg, 0); 1550 } 1551 1552 #ifdef INET6 1553 1554 void 1555 tcp6_ctlinput(netmsg_t msg) 1556 { 1557 int cmd = msg->ctlinput.nm_cmd; 1558 struct sockaddr *sa = msg->ctlinput.nm_arg; 1559 void *d = msg->ctlinput.nm_extra; 1560 struct tcphdr th; 1561 inp_notify_t notify = tcp_notify; 1562 struct ip6_hdr *ip6; 1563 struct mbuf *m; 1564 struct ip6ctlparam *ip6cp = NULL; 1565 const struct sockaddr_in6 *sa6_src = NULL; 1566 int off; 1567 struct tcp_portonly { 1568 u_int16_t th_sport; 1569 u_int16_t th_dport; 1570 } *thp; 1571 int arg; 1572 1573 if (sa->sa_family != AF_INET6 || 1574 sa->sa_len != sizeof(struct sockaddr_in6)) { 1575 goto out; 1576 } 1577 1578 arg = 0; 1579 if (cmd == PRC_QUENCH) 1580 notify = tcp_quench; 1581 else if (cmd == PRC_MSGSIZE) { 1582 struct ip6ctlparam *ip6cp = d; 1583 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6; 1584 1585 arg = ntohl(icmp6->icmp6_mtu); 1586 notify = tcp_mtudisc; 1587 } else if (!PRC_IS_REDIRECT(cmd) && 1588 ((unsigned)cmd > PRC_NCMDS || inet6ctlerrmap[cmd] == 0)) { 1589 goto out; 1590 } 1591 1592 /* if the parameter is from icmp6, decode it. */ 1593 if (d != NULL) { 1594 ip6cp = (struct ip6ctlparam *)d; 1595 m = ip6cp->ip6c_m; 1596 ip6 = ip6cp->ip6c_ip6; 1597 off = ip6cp->ip6c_off; 1598 sa6_src = ip6cp->ip6c_src; 1599 } else { 1600 m = NULL; 1601 ip6 = NULL; 1602 off = 0; /* fool gcc */ 1603 sa6_src = &sa6_any; 1604 } 1605 1606 if (ip6 != NULL) { 1607 struct in_conninfo inc; 1608 /* 1609 * XXX: We assume that when IPV6 is non NULL, 1610 * M and OFF are valid. 1611 */ 1612 1613 /* check if we can safely examine src and dst ports */ 1614 if (m->m_pkthdr.len < off + sizeof *thp) 1615 goto out; 1616 1617 bzero(&th, sizeof th); 1618 m_copydata(m, off, sizeof *thp, (caddr_t)&th); 1619 1620 in6_pcbnotify(&tcbinfo[0], sa, th.th_dport, 1621 (struct sockaddr *)ip6cp->ip6c_src, 1622 th.th_sport, cmd, arg, notify); 1623 1624 inc.inc_fport = th.th_dport; 1625 inc.inc_lport = th.th_sport; 1626 inc.inc6_faddr = ((struct sockaddr_in6 *)sa)->sin6_addr; 1627 inc.inc6_laddr = ip6cp->ip6c_src->sin6_addr; 1628 inc.inc_isipv6 = 1; 1629 syncache_unreach(&inc, &th); 1630 } else { 1631 in6_pcbnotify(&tcbinfo[0], sa, 0, 1632 (const struct sockaddr *)sa6_src, 0, cmd, arg, notify); 1633 } 1634 out: 1635 lwkt_replymsg(&msg->ctlinput.base.lmsg, 0); 1636 } 1637 1638 #endif 1639 1640 /* 1641 * Following is where TCP initial sequence number generation occurs. 1642 * 1643 * There are two places where we must use initial sequence numbers: 1644 * 1. In SYN-ACK packets. 1645 * 2. In SYN packets. 1646 * 1647 * All ISNs for SYN-ACK packets are generated by the syncache. See 1648 * tcp_syncache.c for details. 1649 * 1650 * The ISNs in SYN packets must be monotonic; TIME_WAIT recycling 1651 * depends on this property. In addition, these ISNs should be 1652 * unguessable so as to prevent connection hijacking. To satisfy 1653 * the requirements of this situation, the algorithm outlined in 1654 * RFC 1948 is used to generate sequence numbers. 1655 * 1656 * Implementation details: 1657 * 1658 * Time is based off the system timer, and is corrected so that it 1659 * increases by one megabyte per second. This allows for proper 1660 * recycling on high speed LANs while still leaving over an hour 1661 * before rollover. 1662 * 1663 * net.inet.tcp.isn_reseed_interval controls the number of seconds 1664 * between seeding of isn_secret. This is normally set to zero, 1665 * as reseeding should not be necessary. 1666 * 1667 */ 1668 1669 #define ISN_BYTES_PER_SECOND 1048576 1670 1671 u_char isn_secret[32]; 1672 int isn_last_reseed; 1673 MD5_CTX isn_ctx; 1674 1675 tcp_seq 1676 tcp_new_isn(struct tcpcb *tp) 1677 { 1678 u_int32_t md5_buffer[4]; 1679 tcp_seq new_isn; 1680 1681 /* Seed if this is the first use, reseed if requested. */ 1682 if ((isn_last_reseed == 0) || ((tcp_isn_reseed_interval > 0) && 1683 (((u_int)isn_last_reseed + (u_int)tcp_isn_reseed_interval*hz) 1684 < (u_int)ticks))) { 1685 read_random_unlimited(&isn_secret, sizeof isn_secret); 1686 isn_last_reseed = ticks; 1687 } 1688 1689 /* Compute the md5 hash and return the ISN. */ 1690 MD5Init(&isn_ctx); 1691 MD5Update(&isn_ctx, (u_char *)&tp->t_inpcb->inp_fport, sizeof(u_short)); 1692 MD5Update(&isn_ctx, (u_char *)&tp->t_inpcb->inp_lport, sizeof(u_short)); 1693 #ifdef INET6 1694 if (INP_ISIPV6(tp->t_inpcb)) { 1695 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->in6p_faddr, 1696 sizeof(struct in6_addr)); 1697 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->in6p_laddr, 1698 sizeof(struct in6_addr)); 1699 } else 1700 #endif 1701 { 1702 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_faddr, 1703 sizeof(struct in_addr)); 1704 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_laddr, 1705 sizeof(struct in_addr)); 1706 } 1707 MD5Update(&isn_ctx, (u_char *) &isn_secret, sizeof(isn_secret)); 1708 MD5Final((u_char *) &md5_buffer, &isn_ctx); 1709 new_isn = (tcp_seq) md5_buffer[0]; 1710 new_isn += ticks * (ISN_BYTES_PER_SECOND / hz); 1711 return (new_isn); 1712 } 1713 1714 /* 1715 * When a source quench is received, close congestion window 1716 * to one segment. We will gradually open it again as we proceed. 1717 */ 1718 void 1719 tcp_quench(struct inpcb *inp, int error) 1720 { 1721 struct tcpcb *tp = intotcpcb(inp); 1722 1723 KASSERT(tp != NULL, ("tcp_quench: tp is NULL")); 1724 tp->snd_cwnd = tp->t_maxseg; 1725 tp->snd_wacked = 0; 1726 } 1727 1728 /* 1729 * When a specific ICMP unreachable message is received and the 1730 * connection state is SYN-SENT, drop the connection. This behavior 1731 * is controlled by the icmp_may_rst sysctl. 1732 */ 1733 void 1734 tcp_drop_syn_sent(struct inpcb *inp, int error) 1735 { 1736 struct tcpcb *tp = intotcpcb(inp); 1737 1738 KASSERT(tp != NULL, ("tcp_drop_syn_sent: tp is NULL")); 1739 if (tp->t_state == TCPS_SYN_SENT) 1740 tcp_drop(tp, error); 1741 } 1742 1743 /* 1744 * When a `need fragmentation' ICMP is received, update our idea of the MSS 1745 * based on the new value in the route. Also nudge TCP to send something, 1746 * since we know the packet we just sent was dropped. 1747 * This duplicates some code in the tcp_mss() function in tcp_input.c. 1748 */ 1749 void 1750 tcp_mtudisc(struct inpcb *inp, int mtu) 1751 { 1752 struct tcpcb *tp = intotcpcb(inp); 1753 struct rtentry *rt; 1754 struct socket *so = inp->inp_socket; 1755 int maxopd, mss; 1756 #ifdef INET6 1757 boolean_t isipv6 = INP_ISIPV6(inp); 1758 #else 1759 const boolean_t isipv6 = FALSE; 1760 #endif 1761 1762 KASSERT(tp != NULL, ("tcp_mtudisc: tp is NULL")); 1763 1764 /* 1765 * If no MTU is provided in the ICMP message, use the 1766 * next lower likely value, as specified in RFC 1191. 1767 */ 1768 if (mtu == 0) { 1769 int oldmtu; 1770 1771 oldmtu = tp->t_maxopd + 1772 (isipv6 ? 1773 sizeof(struct ip6_hdr) + sizeof(struct tcphdr) : 1774 sizeof(struct tcpiphdr)); 1775 mtu = ip_next_mtu(oldmtu, 0); 1776 } 1777 1778 if (isipv6) 1779 rt = tcp_rtlookup6(&inp->inp_inc); 1780 else 1781 rt = tcp_rtlookup(&inp->inp_inc); 1782 if (rt != NULL) { 1783 if (rt->rt_rmx.rmx_mtu != 0 && rt->rt_rmx.rmx_mtu < mtu) 1784 mtu = rt->rt_rmx.rmx_mtu; 1785 1786 maxopd = mtu - 1787 (isipv6 ? 1788 sizeof(struct ip6_hdr) + sizeof(struct tcphdr) : 1789 sizeof(struct tcpiphdr)); 1790 1791 /* 1792 * XXX - The following conditional probably violates the TCP 1793 * spec. The problem is that, since we don't know the 1794 * other end's MSS, we are supposed to use a conservative 1795 * default. But, if we do that, then MTU discovery will 1796 * never actually take place, because the conservative 1797 * default is much less than the MTUs typically seen 1798 * on the Internet today. For the moment, we'll sweep 1799 * this under the carpet. 1800 * 1801 * The conservative default might not actually be a problem 1802 * if the only case this occurs is when sending an initial 1803 * SYN with options and data to a host we've never talked 1804 * to before. Then, they will reply with an MSS value which 1805 * will get recorded and the new parameters should get 1806 * recomputed. For Further Study. 1807 */ 1808 if (rt->rt_rmx.rmx_mssopt && rt->rt_rmx.rmx_mssopt < maxopd) 1809 maxopd = rt->rt_rmx.rmx_mssopt; 1810 } else 1811 maxopd = mtu - 1812 (isipv6 ? 1813 sizeof(struct ip6_hdr) + sizeof(struct tcphdr) : 1814 sizeof(struct tcpiphdr)); 1815 1816 if (tp->t_maxopd <= maxopd) 1817 return; 1818 tp->t_maxopd = maxopd; 1819 1820 mss = maxopd; 1821 if ((tp->t_flags & (TF_REQ_TSTMP | TF_RCVD_TSTMP | TF_NOOPT)) == 1822 (TF_REQ_TSTMP | TF_RCVD_TSTMP)) 1823 mss -= TCPOLEN_TSTAMP_APPA; 1824 1825 /* round down to multiple of MCLBYTES */ 1826 #if (MCLBYTES & (MCLBYTES - 1)) == 0 /* test if MCLBYTES power of 2 */ 1827 if (mss > MCLBYTES) 1828 mss &= ~(MCLBYTES - 1); 1829 #else 1830 if (mss > MCLBYTES) 1831 mss = (mss / MCLBYTES) * MCLBYTES; 1832 #endif 1833 1834 if (so->so_snd.ssb_hiwat < mss) 1835 mss = so->so_snd.ssb_hiwat; 1836 1837 tp->t_maxseg = mss; 1838 tp->t_rtttime = 0; 1839 tp->snd_nxt = tp->snd_una; 1840 tcp_output(tp); 1841 tcpstat.tcps_mturesent++; 1842 } 1843 1844 /* 1845 * Look-up the routing entry to the peer of this inpcb. If no route 1846 * is found and it cannot be allocated the return NULL. This routine 1847 * is called by TCP routines that access the rmx structure and by tcp_mss 1848 * to get the interface MTU. 1849 */ 1850 struct rtentry * 1851 tcp_rtlookup(struct in_conninfo *inc) 1852 { 1853 struct route *ro = &inc->inc_route; 1854 1855 if (ro->ro_rt == NULL || !(ro->ro_rt->rt_flags & RTF_UP)) { 1856 /* No route yet, so try to acquire one */ 1857 if (inc->inc_faddr.s_addr != INADDR_ANY) { 1858 /* 1859 * unused portions of the structure MUST be zero'd 1860 * out because rtalloc() treats it as opaque data 1861 */ 1862 bzero(&ro->ro_dst, sizeof(struct sockaddr_in)); 1863 ro->ro_dst.sa_family = AF_INET; 1864 ro->ro_dst.sa_len = sizeof(struct sockaddr_in); 1865 ((struct sockaddr_in *) &ro->ro_dst)->sin_addr = 1866 inc->inc_faddr; 1867 rtalloc(ro); 1868 } 1869 } 1870 return (ro->ro_rt); 1871 } 1872 1873 #ifdef INET6 1874 struct rtentry * 1875 tcp_rtlookup6(struct in_conninfo *inc) 1876 { 1877 struct route_in6 *ro6 = &inc->inc6_route; 1878 1879 if (ro6->ro_rt == NULL || !(ro6->ro_rt->rt_flags & RTF_UP)) { 1880 /* No route yet, so try to acquire one */ 1881 if (!IN6_IS_ADDR_UNSPECIFIED(&inc->inc6_faddr)) { 1882 /* 1883 * unused portions of the structure MUST be zero'd 1884 * out because rtalloc() treats it as opaque data 1885 */ 1886 bzero(&ro6->ro_dst, sizeof(struct sockaddr_in6)); 1887 ro6->ro_dst.sin6_family = AF_INET6; 1888 ro6->ro_dst.sin6_len = sizeof(struct sockaddr_in6); 1889 ro6->ro_dst.sin6_addr = inc->inc6_faddr; 1890 rtalloc((struct route *)ro6); 1891 } 1892 } 1893 return (ro6->ro_rt); 1894 } 1895 #endif 1896 1897 #ifdef IPSEC 1898 /* compute ESP/AH header size for TCP, including outer IP header. */ 1899 size_t 1900 ipsec_hdrsiz_tcp(struct tcpcb *tp) 1901 { 1902 struct inpcb *inp; 1903 struct mbuf *m; 1904 size_t hdrsiz; 1905 struct ip *ip; 1906 struct tcphdr *th; 1907 1908 if ((tp == NULL) || ((inp = tp->t_inpcb) == NULL)) 1909 return (0); 1910 MGETHDR(m, M_NOWAIT, MT_DATA); 1911 if (!m) 1912 return (0); 1913 1914 #ifdef INET6 1915 if (INP_ISIPV6(inp)) { 1916 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1917 1918 th = (struct tcphdr *)(ip6 + 1); 1919 m->m_pkthdr.len = m->m_len = 1920 sizeof(struct ip6_hdr) + sizeof(struct tcphdr); 1921 tcp_fillheaders(tp, ip6, th, FALSE); 1922 hdrsiz = ipsec6_hdrsiz(m, IPSEC_DIR_OUTBOUND, inp); 1923 } else 1924 #endif 1925 { 1926 ip = mtod(m, struct ip *); 1927 th = (struct tcphdr *)(ip + 1); 1928 m->m_pkthdr.len = m->m_len = sizeof(struct tcpiphdr); 1929 tcp_fillheaders(tp, ip, th, FALSE); 1930 hdrsiz = ipsec4_hdrsiz(m, IPSEC_DIR_OUTBOUND, inp); 1931 } 1932 1933 m_free(m); 1934 return (hdrsiz); 1935 } 1936 #endif 1937 1938 /* 1939 * TCP BANDWIDTH DELAY PRODUCT WINDOW LIMITING 1940 * 1941 * This code attempts to calculate the bandwidth-delay product as a 1942 * means of determining the optimal window size to maximize bandwidth, 1943 * minimize RTT, and avoid the over-allocation of buffers on interfaces and 1944 * routers. This code also does a fairly good job keeping RTTs in check 1945 * across slow links like modems. We implement an algorithm which is very 1946 * similar (but not meant to be) TCP/Vegas. The code operates on the 1947 * transmitter side of a TCP connection and so only effects the transmit 1948 * side of the connection. 1949 * 1950 * BACKGROUND: TCP makes no provision for the management of buffer space 1951 * at the end points or at the intermediate routers and switches. A TCP 1952 * stream, whether using NewReno or not, will eventually buffer as 1953 * many packets as it is able and the only reason this typically works is 1954 * due to the fairly small default buffers made available for a connection 1955 * (typicaly 16K or 32K). As machines use larger windows and/or window 1956 * scaling it is now fairly easy for even a single TCP connection to blow-out 1957 * all available buffer space not only on the local interface, but on 1958 * intermediate routers and switches as well. NewReno makes a misguided 1959 * attempt to 'solve' this problem by waiting for an actual failure to occur, 1960 * then backing off, then steadily increasing the window again until another 1961 * failure occurs, ad-infinitum. This results in terrible oscillation that 1962 * is only made worse as network loads increase and the idea of intentionally 1963 * blowing out network buffers is, frankly, a terrible way to manage network 1964 * resources. 1965 * 1966 * It is far better to limit the transmit window prior to the failure 1967 * condition being achieved. There are two general ways to do this: First 1968 * you can 'scan' through different transmit window sizes and locate the 1969 * point where the RTT stops increasing, indicating that you have filled the 1970 * pipe, then scan backwards until you note that RTT stops decreasing, then 1971 * repeat ad-infinitum. This method works in principle but has severe 1972 * implementation issues due to RTT variances, timer granularity, and 1973 * instability in the algorithm which can lead to many false positives and 1974 * create oscillations as well as interact badly with other TCP streams 1975 * implementing the same algorithm. 1976 * 1977 * The second method is to limit the window to the bandwidth delay product 1978 * of the link. This is the method we implement. RTT variances and our 1979 * own manipulation of the congestion window, bwnd, can potentially 1980 * destabilize the algorithm. For this reason we have to stabilize the 1981 * elements used to calculate the window. We do this by using the minimum 1982 * observed RTT, the long term average of the observed bandwidth, and 1983 * by adding two segments worth of slop. It isn't perfect but it is able 1984 * to react to changing conditions and gives us a very stable basis on 1985 * which to extend the algorithm. 1986 */ 1987 void 1988 tcp_xmit_bandwidth_limit(struct tcpcb *tp, tcp_seq ack_seq) 1989 { 1990 u_long bw; 1991 u_long ibw; 1992 u_long bwnd; 1993 int save_ticks; 1994 int delta_ticks; 1995 1996 /* 1997 * If inflight_enable is disabled in the middle of a tcp connection, 1998 * make sure snd_bwnd is effectively disabled. 1999 */ 2000 if (!tcp_inflight_enable) { 2001 tp->snd_bwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT; 2002 tp->snd_bandwidth = 0; 2003 return; 2004 } 2005 2006 /* 2007 * Validate the delta time. If a connection is new or has been idle 2008 * a long time we have to reset the bandwidth calculator. 2009 */ 2010 save_ticks = ticks; 2011 cpu_ccfence(); 2012 delta_ticks = save_ticks - tp->t_bw_rtttime; 2013 if (tp->t_bw_rtttime == 0 || delta_ticks < 0 || delta_ticks > hz * 10) { 2014 tp->t_bw_rtttime = save_ticks; 2015 tp->t_bw_rtseq = ack_seq; 2016 if (tp->snd_bandwidth == 0) 2017 tp->snd_bandwidth = tcp_inflight_start; 2018 return; 2019 } 2020 2021 /* 2022 * A delta of at least 1 tick is required. Waiting 2 ticks will 2023 * result in better (bw) accuracy. More than that and the ramp-up 2024 * will be too slow. 2025 */ 2026 if (delta_ticks == 0 || delta_ticks == 1) 2027 return; 2028 2029 /* 2030 * Sanity check, plus ignore pure window update acks. 2031 */ 2032 if ((int)(ack_seq - tp->t_bw_rtseq) <= 0) 2033 return; 2034 2035 /* 2036 * Figure out the bandwidth. Due to the tick granularity this 2037 * is a very rough number and it MUST be averaged over a fairly 2038 * long period of time. XXX we need to take into account a link 2039 * that is not using all available bandwidth, but for now our 2040 * slop will ramp us up if this case occurs and the bandwidth later 2041 * increases. 2042 */ 2043 ibw = (int64_t)(ack_seq - tp->t_bw_rtseq) * hz / delta_ticks; 2044 tp->t_bw_rtttime = save_ticks; 2045 tp->t_bw_rtseq = ack_seq; 2046 bw = ((int64_t)tp->snd_bandwidth * 15 + ibw) >> 4; 2047 2048 tp->snd_bandwidth = bw; 2049 2050 /* 2051 * Calculate the semi-static bandwidth delay product, plus two maximal 2052 * segments. The additional slop puts us squarely in the sweet 2053 * spot and also handles the bandwidth run-up case. Without the 2054 * slop we could be locking ourselves into a lower bandwidth. 2055 * 2056 * At very high speeds the bw calculation can become overly sensitive 2057 * and error prone when delta_ticks is low (e.g. usually 1). To deal 2058 * with the problem the stab must be scaled to the bw. A stab of 50 2059 * (the default) increases the bw for the purposes of the bwnd 2060 * calculation by 5%. 2061 * 2062 * Situations Handled: 2063 * (1) Prevents over-queueing of packets on LANs, especially on 2064 * high speed LANs, allowing larger TCP buffers to be 2065 * specified, and also does a good job preventing 2066 * over-queueing of packets over choke points like modems 2067 * (at least for the transmit side). 2068 * 2069 * (2) Is able to handle changing network loads (bandwidth 2070 * drops so bwnd drops, bandwidth increases so bwnd 2071 * increases). 2072 * 2073 * (3) Theoretically should stabilize in the face of multiple 2074 * connections implementing the same algorithm (this may need 2075 * a little work). 2076 * 2077 * (4) Stability value (defaults to 20 = 2 maximal packets) can 2078 * be adjusted with a sysctl but typically only needs to be on 2079 * very slow connections. A value no smaller then 5 should 2080 * be used, but only reduce this default if you have no other 2081 * choice. 2082 */ 2083 2084 #define USERTT ((tp->t_srtt + tp->t_rttvar) + tcp_inflight_adjrtt) 2085 bw += bw * tcp_inflight_stab / 1000; 2086 bwnd = (int64_t)bw * USERTT / (hz << TCP_RTT_SHIFT) + 2087 (int)tp->t_maxseg * 2; 2088 #undef USERTT 2089 2090 if (tcp_inflight_debug > 0) { 2091 static int ltime; 2092 if ((u_int)(save_ticks - ltime) >= hz / tcp_inflight_debug) { 2093 ltime = save_ticks; 2094 kprintf("%p ibw %ld bw %ld rttvar %d srtt %d " 2095 "bwnd %ld delta %d snd_win %ld\n", 2096 tp, ibw, bw, tp->t_rttvar, tp->t_srtt, 2097 bwnd, delta_ticks, tp->snd_wnd); 2098 } 2099 } 2100 if ((long)bwnd < tcp_inflight_min) 2101 bwnd = tcp_inflight_min; 2102 if (bwnd > tcp_inflight_max) 2103 bwnd = tcp_inflight_max; 2104 if ((long)bwnd < tp->t_maxseg * 2) 2105 bwnd = tp->t_maxseg * 2; 2106 tp->snd_bwnd = bwnd; 2107 } 2108 2109 static void 2110 tcp_rmx_iwsegs(struct tcpcb *tp, u_long *maxsegs, u_long *capsegs) 2111 { 2112 struct rtentry *rt; 2113 struct inpcb *inp = tp->t_inpcb; 2114 #ifdef INET6 2115 boolean_t isipv6 = INP_ISIPV6(inp); 2116 #else 2117 const boolean_t isipv6 = FALSE; 2118 #endif 2119 2120 /* XXX */ 2121 if (tcp_iw_maxsegs < TCP_IW_MAXSEGS_DFLT) 2122 tcp_iw_maxsegs = TCP_IW_MAXSEGS_DFLT; 2123 if (tcp_iw_capsegs < TCP_IW_CAPSEGS_DFLT) 2124 tcp_iw_capsegs = TCP_IW_CAPSEGS_DFLT; 2125 2126 if (isipv6) 2127 rt = tcp_rtlookup6(&inp->inp_inc); 2128 else 2129 rt = tcp_rtlookup(&inp->inp_inc); 2130 if (rt == NULL || 2131 rt->rt_rmx.rmx_iwmaxsegs < TCP_IW_MAXSEGS_DFLT || 2132 rt->rt_rmx.rmx_iwcapsegs < TCP_IW_CAPSEGS_DFLT) { 2133 *maxsegs = tcp_iw_maxsegs; 2134 *capsegs = tcp_iw_capsegs; 2135 return; 2136 } 2137 *maxsegs = rt->rt_rmx.rmx_iwmaxsegs; 2138 *capsegs = rt->rt_rmx.rmx_iwcapsegs; 2139 } 2140 2141 u_long 2142 tcp_initial_window(struct tcpcb *tp) 2143 { 2144 if (tcp_do_rfc3390) { 2145 /* 2146 * RFC3390: 2147 * "If the SYN or SYN/ACK is lost, the initial window 2148 * used by a sender after a correctly transmitted SYN 2149 * MUST be one segment consisting of MSS bytes." 2150 * 2151 * However, we do something a little bit more aggressive 2152 * then RFC3390 here: 2153 * - Only if time spent in the SYN or SYN|ACK retransmition 2154 * >= 3 seconds, the IW is reduced. We do this mainly 2155 * because when RFC3390 is published, the initial RTO is 2156 * still 3 seconds (the threshold we test here), while 2157 * after RFC6298, the initial RTO is 1 second. This 2158 * behaviour probably still falls within the spirit of 2159 * RFC3390. 2160 * - When IW is reduced, 2*MSS is used instead of 1*MSS. 2161 * Mainly to avoid sender and receiver deadlock until 2162 * delayed ACK timer expires. And even RFC2581 does not 2163 * try to reduce IW upon SYN or SYN|ACK retransmition 2164 * timeout. 2165 * 2166 * See also: 2167 * http://tools.ietf.org/html/draft-ietf-tcpm-initcwnd-03 2168 */ 2169 if (tp->t_rxtsyn >= TCPTV_RTOBASE3) { 2170 return (2 * tp->t_maxseg); 2171 } else { 2172 u_long maxsegs, capsegs; 2173 2174 tcp_rmx_iwsegs(tp, &maxsegs, &capsegs); 2175 return min(maxsegs * tp->t_maxseg, 2176 max(2 * tp->t_maxseg, capsegs * 1460)); 2177 } 2178 } else { 2179 /* 2180 * Even RFC2581 (back to 1999) allows 2*SMSS IW. 2181 * 2182 * Mainly to avoid sender and receiver deadlock 2183 * until delayed ACK timer expires. 2184 */ 2185 return (2 * tp->t_maxseg); 2186 } 2187 } 2188 2189 #ifdef TCP_SIGNATURE 2190 /* 2191 * Compute TCP-MD5 hash of a TCP segment. (RFC2385) 2192 * 2193 * We do this over ip, tcphdr, segment data, and the key in the SADB. 2194 * When called from tcp_input(), we can be sure that th_sum has been 2195 * zeroed out and verified already. 2196 * 2197 * Return 0 if successful, otherwise return -1. 2198 * 2199 * XXX The key is retrieved from the system's PF_KEY SADB, by keying a 2200 * search with the destination IP address, and a 'magic SPI' to be 2201 * determined by the application. This is hardcoded elsewhere to 1179 2202 * right now. Another branch of this code exists which uses the SPD to 2203 * specify per-application flows but it is unstable. 2204 */ 2205 int 2206 tcpsignature_compute( 2207 struct mbuf *m, /* mbuf chain */ 2208 int len, /* length of TCP data */ 2209 int optlen, /* length of TCP options */ 2210 u_char *buf, /* storage for MD5 digest */ 2211 u_int direction) /* direction of flow */ 2212 { 2213 struct ippseudo ippseudo; 2214 MD5_CTX ctx; 2215 int doff; 2216 struct ip *ip; 2217 struct ipovly *ipovly; 2218 struct secasvar *sav; 2219 struct tcphdr *th; 2220 #ifdef INET6 2221 struct ip6_hdr *ip6; 2222 struct in6_addr in6; 2223 uint32_t plen; 2224 uint16_t nhdr; 2225 #endif /* INET6 */ 2226 u_short savecsum; 2227 2228 KASSERT(m != NULL, ("passed NULL mbuf. Game over.")); 2229 KASSERT(buf != NULL, ("passed NULL storage pointer for MD5 signature")); 2230 /* 2231 * Extract the destination from the IP header in the mbuf. 2232 */ 2233 ip = mtod(m, struct ip *); 2234 #ifdef INET6 2235 ip6 = NULL; /* Make the compiler happy. */ 2236 #endif /* INET6 */ 2237 /* 2238 * Look up an SADB entry which matches the address found in 2239 * the segment. 2240 */ 2241 switch (IP_VHL_V(ip->ip_vhl)) { 2242 case IPVERSION: 2243 sav = key_allocsa(AF_INET, (caddr_t)&ip->ip_src, (caddr_t)&ip->ip_dst, 2244 IPPROTO_TCP, htonl(TCP_SIG_SPI)); 2245 break; 2246 #ifdef INET6 2247 case (IPV6_VERSION >> 4): 2248 ip6 = mtod(m, struct ip6_hdr *); 2249 sav = key_allocsa(AF_INET6, (caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst, 2250 IPPROTO_TCP, htonl(TCP_SIG_SPI)); 2251 break; 2252 #endif /* INET6 */ 2253 default: 2254 return (EINVAL); 2255 /* NOTREACHED */ 2256 break; 2257 } 2258 if (sav == NULL) { 2259 kprintf("%s: SADB lookup failed\n", __func__); 2260 return (EINVAL); 2261 } 2262 MD5Init(&ctx); 2263 2264 /* 2265 * Step 1: Update MD5 hash with IP pseudo-header. 2266 * 2267 * XXX The ippseudo header MUST be digested in network byte order, 2268 * or else we'll fail the regression test. Assume all fields we've 2269 * been doing arithmetic on have been in host byte order. 2270 * XXX One cannot depend on ipovly->ih_len here. When called from 2271 * tcp_output(), the underlying ip_len member has not yet been set. 2272 */ 2273 switch (IP_VHL_V(ip->ip_vhl)) { 2274 case IPVERSION: 2275 ipovly = (struct ipovly *)ip; 2276 ippseudo.ippseudo_src = ipovly->ih_src; 2277 ippseudo.ippseudo_dst = ipovly->ih_dst; 2278 ippseudo.ippseudo_pad = 0; 2279 ippseudo.ippseudo_p = IPPROTO_TCP; 2280 ippseudo.ippseudo_len = htons(len + sizeof(struct tcphdr) + optlen); 2281 MD5Update(&ctx, (char *)&ippseudo, sizeof(struct ippseudo)); 2282 th = (struct tcphdr *)((u_char *)ip + sizeof(struct ip)); 2283 doff = sizeof(struct ip) + sizeof(struct tcphdr) + optlen; 2284 break; 2285 #ifdef INET6 2286 /* 2287 * RFC 2385, 2.0 Proposal 2288 * For IPv6, the pseudo-header is as described in RFC 2460, namely the 2289 * 128-bit source IPv6 address, 128-bit destination IPv6 address, zero- 2290 * extended next header value (to form 32 bits), and 32-bit segment 2291 * length. 2292 * Note: Upper-Layer Packet Length comes before Next Header. 2293 */ 2294 case (IPV6_VERSION >> 4): 2295 in6 = ip6->ip6_src; 2296 in6_clearscope(&in6); 2297 MD5Update(&ctx, (char *)&in6, sizeof(struct in6_addr)); 2298 in6 = ip6->ip6_dst; 2299 in6_clearscope(&in6); 2300 MD5Update(&ctx, (char *)&in6, sizeof(struct in6_addr)); 2301 plen = htonl(len + sizeof(struct tcphdr) + optlen); 2302 MD5Update(&ctx, (char *)&plen, sizeof(uint32_t)); 2303 nhdr = 0; 2304 MD5Update(&ctx, (char *)&nhdr, sizeof(uint8_t)); 2305 MD5Update(&ctx, (char *)&nhdr, sizeof(uint8_t)); 2306 MD5Update(&ctx, (char *)&nhdr, sizeof(uint8_t)); 2307 nhdr = IPPROTO_TCP; 2308 MD5Update(&ctx, (char *)&nhdr, sizeof(uint8_t)); 2309 th = (struct tcphdr *)((u_char *)ip6 + sizeof(struct ip6_hdr)); 2310 doff = sizeof(struct ip6_hdr) + sizeof(struct tcphdr) + optlen; 2311 break; 2312 #endif /* INET6 */ 2313 default: 2314 return (EINVAL); 2315 /* NOTREACHED */ 2316 break; 2317 } 2318 /* 2319 * Step 2: Update MD5 hash with TCP header, excluding options. 2320 * The TCP checksum must be set to zero. 2321 */ 2322 savecsum = th->th_sum; 2323 th->th_sum = 0; 2324 MD5Update(&ctx, (char *)th, sizeof(struct tcphdr)); 2325 th->th_sum = savecsum; 2326 /* 2327 * Step 3: Update MD5 hash with TCP segment data. 2328 * Use m_apply() to avoid an early m_pullup(). 2329 */ 2330 if (len > 0) 2331 m_apply(m, doff, len, tcpsignature_apply, &ctx); 2332 /* 2333 * Step 4: Update MD5 hash with shared secret. 2334 */ 2335 MD5Update(&ctx, _KEYBUF(sav->key_auth), _KEYLEN(sav->key_auth)); 2336 MD5Final(buf, &ctx); 2337 key_sa_recordxfer(sav, m); 2338 key_freesav(sav); 2339 return (0); 2340 } 2341 2342 int 2343 tcpsignature_apply(void *fstate, void *data, unsigned int len) 2344 { 2345 2346 MD5Update((MD5_CTX *)fstate, (unsigned char *)data, len); 2347 return (0); 2348 } 2349 #endif /* TCP_SIGNATURE */ 2350 2351 static void 2352 tcp_drop_sysctl_dispatch(netmsg_t nmsg) 2353 { 2354 struct lwkt_msg *lmsg = &nmsg->lmsg; 2355 /* addrs[0] is a foreign socket, addrs[1] is a local one. */ 2356 struct sockaddr_storage *addrs = lmsg->u.ms_resultp; 2357 int error; 2358 struct sockaddr_in *fin, *lin; 2359 #ifdef INET6 2360 struct sockaddr_in6 *fin6, *lin6; 2361 struct in6_addr f6, l6; 2362 #endif 2363 struct inpcb *inp; 2364 2365 switch (addrs[0].ss_family) { 2366 #ifdef INET6 2367 case AF_INET6: 2368 fin6 = (struct sockaddr_in6 *)&addrs[0]; 2369 lin6 = (struct sockaddr_in6 *)&addrs[1]; 2370 error = in6_embedscope(&f6, fin6, NULL, NULL); 2371 if (error) 2372 goto done; 2373 error = in6_embedscope(&l6, lin6, NULL, NULL); 2374 if (error) 2375 goto done; 2376 inp = in6_pcblookup_hash(&tcbinfo[mycpuid], &f6, 2377 fin6->sin6_port, &l6, lin6->sin6_port, FALSE, NULL); 2378 break; 2379 #endif 2380 #ifdef INET 2381 case AF_INET: 2382 fin = (struct sockaddr_in *)&addrs[0]; 2383 lin = (struct sockaddr_in *)&addrs[1]; 2384 inp = in_pcblookup_hash(&tcbinfo[mycpuid], fin->sin_addr, 2385 fin->sin_port, lin->sin_addr, lin->sin_port, FALSE, NULL); 2386 break; 2387 #endif 2388 default: 2389 /* 2390 * Must not reach here, since the address family was 2391 * checked in sysctl handler. 2392 */ 2393 panic("unknown address family %d", addrs[0].ss_family); 2394 } 2395 if (inp != NULL) { 2396 struct tcpcb *tp = intotcpcb(inp); 2397 2398 KASSERT((inp->inp_flags & INP_WILDCARD) == 0, 2399 ("in wildcard hash")); 2400 KASSERT(tp != NULL, ("tcp_drop_sysctl_dispatch: tp is NULL")); 2401 KASSERT((tp->t_flags & TF_LISTEN) == 0, ("listen socket")); 2402 tcp_drop(tp, ECONNABORTED); 2403 error = 0; 2404 } else { 2405 error = ESRCH; 2406 } 2407 #ifdef INET6 2408 done: 2409 #endif 2410 lwkt_replymsg(lmsg, error); 2411 } 2412 2413 static int 2414 sysctl_tcp_drop(SYSCTL_HANDLER_ARGS) 2415 { 2416 /* addrs[0] is a foreign socket, addrs[1] is a local one. */ 2417 struct sockaddr_storage addrs[2]; 2418 struct sockaddr_in *fin, *lin; 2419 #ifdef INET6 2420 struct sockaddr_in6 *fin6, *lin6; 2421 #endif 2422 struct netmsg_base nmsg; 2423 struct lwkt_msg *lmsg = &nmsg.lmsg; 2424 struct lwkt_port *port = NULL; 2425 int error; 2426 2427 fin = lin = NULL; 2428 #ifdef INET6 2429 fin6 = lin6 = NULL; 2430 #endif 2431 error = 0; 2432 2433 if (req->oldptr != NULL || req->oldlen != 0) 2434 return (EINVAL); 2435 if (req->newptr == NULL) 2436 return (EPERM); 2437 if (req->newlen < sizeof(addrs)) 2438 return (ENOMEM); 2439 error = SYSCTL_IN(req, &addrs, sizeof(addrs)); 2440 if (error) 2441 return (error); 2442 2443 switch (addrs[0].ss_family) { 2444 #ifdef INET6 2445 case AF_INET6: 2446 fin6 = (struct sockaddr_in6 *)&addrs[0]; 2447 lin6 = (struct sockaddr_in6 *)&addrs[1]; 2448 if (fin6->sin6_len != sizeof(struct sockaddr_in6) || 2449 lin6->sin6_len != sizeof(struct sockaddr_in6)) 2450 return (EINVAL); 2451 if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr) || 2452 IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr)) 2453 return (EADDRNOTAVAIL); 2454 #if 0 2455 error = sa6_embedscope(fin6, V_ip6_use_defzone); 2456 if (error) 2457 return (error); 2458 error = sa6_embedscope(lin6, V_ip6_use_defzone); 2459 if (error) 2460 return (error); 2461 #endif 2462 port = tcp6_addrport(); 2463 break; 2464 #endif 2465 #ifdef INET 2466 case AF_INET: 2467 fin = (struct sockaddr_in *)&addrs[0]; 2468 lin = (struct sockaddr_in *)&addrs[1]; 2469 if (fin->sin_len != sizeof(struct sockaddr_in) || 2470 lin->sin_len != sizeof(struct sockaddr_in)) 2471 return (EINVAL); 2472 port = tcp_addrport(fin->sin_addr.s_addr, fin->sin_port, 2473 lin->sin_addr.s_addr, lin->sin_port); 2474 break; 2475 #endif 2476 default: 2477 return (EINVAL); 2478 } 2479 2480 netmsg_init(&nmsg, NULL, &curthread->td_msgport, 0, 2481 tcp_drop_sysctl_dispatch); 2482 lmsg->u.ms_resultp = addrs; 2483 return lwkt_domsg(port, lmsg, 0); 2484 } 2485 2486 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, drop, 2487 CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP, NULL, 2488 0, sysctl_tcp_drop, "", "Drop TCP connection"); 2489 2490 static int 2491 sysctl_tcps_count(SYSCTL_HANDLER_ARGS) 2492 { 2493 u_long state_count[TCP_NSTATES]; 2494 int cpu; 2495 2496 memset(state_count, 0, sizeof(state_count)); 2497 for (cpu = 0; cpu < netisr_ncpus; ++cpu) { 2498 int i; 2499 2500 for (i = 0; i < TCP_NSTATES; ++i) 2501 state_count[i] += tcpstate_count[cpu].tcps_count[i]; 2502 } 2503 2504 return sysctl_handle_opaque(oidp, state_count, sizeof(state_count), req); 2505 } 2506 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, state_count, 2507 CTLTYPE_OPAQUE | CTLFLAG_RD, NULL, 0, 2508 sysctl_tcps_count, "LU", "TCP connection counts by state"); 2509 2510 void 2511 tcp_pcbport_create(struct tcpcb *tp) 2512 { 2513 int cpu; 2514 2515 KASSERT((tp->t_flags & TF_LISTEN) && tp->t_state == TCPS_LISTEN, 2516 ("not a listen tcpcb")); 2517 2518 KASSERT(tp->t_pcbport == NULL, ("tcpcb port cache was created")); 2519 tp->t_pcbport = kmalloc_cachealign( 2520 sizeof(struct tcp_pcbport) * netisr_ncpus, M_PCB, M_WAITOK); 2521 2522 for (cpu = 0; cpu < netisr_ncpus; ++cpu) { 2523 struct inpcbport *phd; 2524 2525 phd = &tp->t_pcbport[cpu].t_phd; 2526 LIST_INIT(&phd->phd_pcblist); 2527 /* Though, not used ... */ 2528 phd->phd_port = tp->t_inpcb->inp_lport; 2529 } 2530 } 2531 2532 void 2533 tcp_pcbport_merge_oncpu(struct tcpcb *tp) 2534 { 2535 struct inpcbport *phd; 2536 struct inpcb *inp; 2537 int cpu = mycpuid; 2538 2539 KASSERT(cpu < netisr_ncpus, ("invalid cpu%d", cpu)); 2540 phd = &tp->t_pcbport[cpu].t_phd; 2541 2542 while ((inp = LIST_FIRST(&phd->phd_pcblist)) != NULL) { 2543 KASSERT(inp->inp_phd == phd && inp->inp_porthash == NULL, 2544 ("not on tcpcb port cache")); 2545 LIST_REMOVE(inp, inp_portlist); 2546 in_pcbinsporthash_lport(inp); 2547 KASSERT(inp->inp_phd == tp->t_inpcb->inp_phd && 2548 inp->inp_porthash == tp->t_inpcb->inp_porthash, 2549 ("tcpcb port cache merge failed")); 2550 } 2551 } 2552 2553 void 2554 tcp_pcbport_destroy(struct tcpcb *tp) 2555 { 2556 #ifdef INVARIANTS 2557 int cpu; 2558 2559 for (cpu = 0; cpu < netisr_ncpus; ++cpu) { 2560 KASSERT(LIST_EMPTY(&tp->t_pcbport[cpu].t_phd.phd_pcblist), 2561 ("tcpcb port cache is not empty")); 2562 } 2563 #endif 2564 kfree(tp->t_pcbport, M_PCB); 2565 tp->t_pcbport = NULL; 2566 } 2567