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