1 /* 2 * TCP over IPv6 3 * Linux INET6 implementation 4 * 5 * Authors: 6 * Pedro Roque <roque@di.fc.ul.pt> 7 * 8 * $Id: tcp_ipv6.c,v 1.144 2002/02/01 22:01:04 davem Exp $ 9 * 10 * Based on: 11 * linux/net/ipv4/tcp.c 12 * linux/net/ipv4/tcp_input.c 13 * linux/net/ipv4/tcp_output.c 14 * 15 * Fixes: 16 * Hideaki YOSHIFUJI : sin6_scope_id support 17 * YOSHIFUJI Hideaki @USAGI and: Support IPV6_V6ONLY socket option, which 18 * Alexey Kuznetsov allow both IPv4 and IPv6 sockets to bind 19 * a single port at the same time. 20 * YOSHIFUJI Hideaki @USAGI: convert /proc/net/tcp6 to seq_file. 21 * 22 * This program is free software; you can redistribute it and/or 23 * modify it under the terms of the GNU General Public License 24 * as published by the Free Software Foundation; either version 25 * 2 of the License, or (at your option) any later version. 26 */ 27 28 #include <linux/module.h> 29 #include <linux/config.h> 30 #include <linux/errno.h> 31 #include <linux/types.h> 32 #include <linux/socket.h> 33 #include <linux/sockios.h> 34 #include <linux/net.h> 35 #include <linux/jiffies.h> 36 #include <linux/in.h> 37 #include <linux/in6.h> 38 #include <linux/netdevice.h> 39 #include <linux/init.h> 40 #include <linux/jhash.h> 41 #include <linux/ipsec.h> 42 #include <linux/times.h> 43 44 #include <linux/ipv6.h> 45 #include <linux/icmpv6.h> 46 #include <linux/random.h> 47 48 #include <net/tcp.h> 49 #include <net/ndisc.h> 50 #include <net/inet6_hashtables.h> 51 #include <net/ipv6.h> 52 #include <net/transp_v6.h> 53 #include <net/addrconf.h> 54 #include <net/ip6_route.h> 55 #include <net/ip6_checksum.h> 56 #include <net/inet_ecn.h> 57 #include <net/protocol.h> 58 #include <net/xfrm.h> 59 #include <net/addrconf.h> 60 #include <net/snmp.h> 61 #include <net/dsfield.h> 62 63 #include <asm/uaccess.h> 64 65 #include <linux/proc_fs.h> 66 #include <linux/seq_file.h> 67 68 static void tcp_v6_send_reset(struct sk_buff *skb); 69 static void tcp_v6_reqsk_send_ack(struct sk_buff *skb, struct request_sock *req); 70 static void tcp_v6_send_check(struct sock *sk, struct tcphdr *th, int len, 71 struct sk_buff *skb); 72 73 static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb); 74 static int tcp_v6_xmit(struct sk_buff *skb, int ipfragok); 75 76 static struct tcp_func ipv6_mapped; 77 static struct tcp_func ipv6_specific; 78 79 static inline int tcp_v6_bind_conflict(const struct sock *sk, 80 const struct inet_bind_bucket *tb) 81 { 82 const struct sock *sk2; 83 const struct hlist_node *node; 84 85 /* We must walk the whole port owner list in this case. -DaveM */ 86 sk_for_each_bound(sk2, node, &tb->owners) { 87 if (sk != sk2 && 88 (!sk->sk_bound_dev_if || 89 !sk2->sk_bound_dev_if || 90 sk->sk_bound_dev_if == sk2->sk_bound_dev_if) && 91 (!sk->sk_reuse || !sk2->sk_reuse || 92 sk2->sk_state == TCP_LISTEN) && 93 ipv6_rcv_saddr_equal(sk, sk2)) 94 break; 95 } 96 97 return node != NULL; 98 } 99 100 /* Grrr, addr_type already calculated by caller, but I don't want 101 * to add some silly "cookie" argument to this method just for that. 102 * But it doesn't matter, the recalculation is in the rarest path 103 * this function ever takes. 104 */ 105 static int tcp_v6_get_port(struct sock *sk, unsigned short snum) 106 { 107 struct inet_bind_hashbucket *head; 108 struct inet_bind_bucket *tb; 109 struct hlist_node *node; 110 int ret; 111 112 local_bh_disable(); 113 if (snum == 0) { 114 int low = sysctl_local_port_range[0]; 115 int high = sysctl_local_port_range[1]; 116 int remaining = (high - low) + 1; 117 int rover; 118 119 spin_lock(&tcp_hashinfo.portalloc_lock); 120 if (tcp_hashinfo.port_rover < low) 121 rover = low; 122 else 123 rover = tcp_hashinfo.port_rover; 124 do { rover++; 125 if (rover > high) 126 rover = low; 127 head = &tcp_hashinfo.bhash[inet_bhashfn(rover, tcp_hashinfo.bhash_size)]; 128 spin_lock(&head->lock); 129 inet_bind_bucket_for_each(tb, node, &head->chain) 130 if (tb->port == rover) 131 goto next; 132 break; 133 next: 134 spin_unlock(&head->lock); 135 } while (--remaining > 0); 136 tcp_hashinfo.port_rover = rover; 137 spin_unlock(&tcp_hashinfo.portalloc_lock); 138 139 /* Exhausted local port range during search? It is not 140 * possible for us to be holding one of the bind hash 141 * locks if this test triggers, because if 'remaining' 142 * drops to zero, we broke out of the do/while loop at 143 * the top level, not from the 'break;' statement. 144 */ 145 ret = 1; 146 if (unlikely(remaining <= 0)) 147 goto fail; 148 149 /* OK, here is the one we will use. */ 150 snum = rover; 151 } else { 152 head = &tcp_hashinfo.bhash[inet_bhashfn(snum, tcp_hashinfo.bhash_size)]; 153 spin_lock(&head->lock); 154 inet_bind_bucket_for_each(tb, node, &head->chain) 155 if (tb->port == snum) 156 goto tb_found; 157 } 158 tb = NULL; 159 goto tb_not_found; 160 tb_found: 161 if (tb && !hlist_empty(&tb->owners)) { 162 if (tb->fastreuse > 0 && sk->sk_reuse && 163 sk->sk_state != TCP_LISTEN) { 164 goto success; 165 } else { 166 ret = 1; 167 if (tcp_v6_bind_conflict(sk, tb)) 168 goto fail_unlock; 169 } 170 } 171 tb_not_found: 172 ret = 1; 173 if (tb == NULL) { 174 tb = inet_bind_bucket_create(tcp_hashinfo.bind_bucket_cachep, head, snum); 175 if (tb == NULL) 176 goto fail_unlock; 177 } 178 if (hlist_empty(&tb->owners)) { 179 if (sk->sk_reuse && sk->sk_state != TCP_LISTEN) 180 tb->fastreuse = 1; 181 else 182 tb->fastreuse = 0; 183 } else if (tb->fastreuse && 184 (!sk->sk_reuse || sk->sk_state == TCP_LISTEN)) 185 tb->fastreuse = 0; 186 187 success: 188 if (!inet_csk(sk)->icsk_bind_hash) 189 inet_bind_hash(sk, tb, snum); 190 BUG_TRAP(inet_csk(sk)->icsk_bind_hash == tb); 191 ret = 0; 192 193 fail_unlock: 194 spin_unlock(&head->lock); 195 fail: 196 local_bh_enable(); 197 return ret; 198 } 199 200 static __inline__ void __tcp_v6_hash(struct sock *sk) 201 { 202 struct hlist_head *list; 203 rwlock_t *lock; 204 205 BUG_TRAP(sk_unhashed(sk)); 206 207 if (sk->sk_state == TCP_LISTEN) { 208 list = &tcp_hashinfo.listening_hash[inet_sk_listen_hashfn(sk)]; 209 lock = &tcp_hashinfo.lhash_lock; 210 inet_listen_wlock(&tcp_hashinfo); 211 } else { 212 sk->sk_hashent = inet6_sk_ehashfn(sk, tcp_hashinfo.ehash_size); 213 list = &tcp_hashinfo.ehash[sk->sk_hashent].chain; 214 lock = &tcp_hashinfo.ehash[sk->sk_hashent].lock; 215 write_lock(lock); 216 } 217 218 __sk_add_node(sk, list); 219 sock_prot_inc_use(sk->sk_prot); 220 write_unlock(lock); 221 } 222 223 224 static void tcp_v6_hash(struct sock *sk) 225 { 226 if (sk->sk_state != TCP_CLOSE) { 227 struct tcp_sock *tp = tcp_sk(sk); 228 229 if (tp->af_specific == &ipv6_mapped) { 230 tcp_prot.hash(sk); 231 return; 232 } 233 local_bh_disable(); 234 __tcp_v6_hash(sk); 235 local_bh_enable(); 236 } 237 } 238 239 /* 240 * Open request hash tables. 241 */ 242 243 static u32 tcp_v6_synq_hash(const struct in6_addr *raddr, const u16 rport, const u32 rnd) 244 { 245 u32 a, b, c; 246 247 a = raddr->s6_addr32[0]; 248 b = raddr->s6_addr32[1]; 249 c = raddr->s6_addr32[2]; 250 251 a += JHASH_GOLDEN_RATIO; 252 b += JHASH_GOLDEN_RATIO; 253 c += rnd; 254 __jhash_mix(a, b, c); 255 256 a += raddr->s6_addr32[3]; 257 b += (u32) rport; 258 __jhash_mix(a, b, c); 259 260 return c & (TCP_SYNQ_HSIZE - 1); 261 } 262 263 static struct request_sock *tcp_v6_search_req(const struct sock *sk, 264 struct request_sock ***prevp, 265 __u16 rport, 266 struct in6_addr *raddr, 267 struct in6_addr *laddr, 268 int iif) 269 { 270 const struct inet_connection_sock *icsk = inet_csk(sk); 271 struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt; 272 struct request_sock *req, **prev; 273 274 for (prev = &lopt->syn_table[tcp_v6_synq_hash(raddr, rport, lopt->hash_rnd)]; 275 (req = *prev) != NULL; 276 prev = &req->dl_next) { 277 const struct tcp6_request_sock *treq = tcp6_rsk(req); 278 279 if (inet_rsk(req)->rmt_port == rport && 280 req->rsk_ops->family == AF_INET6 && 281 ipv6_addr_equal(&treq->rmt_addr, raddr) && 282 ipv6_addr_equal(&treq->loc_addr, laddr) && 283 (!treq->iif || treq->iif == iif)) { 284 BUG_TRAP(req->sk == NULL); 285 *prevp = prev; 286 return req; 287 } 288 } 289 290 return NULL; 291 } 292 293 static __inline__ u16 tcp_v6_check(struct tcphdr *th, int len, 294 struct in6_addr *saddr, 295 struct in6_addr *daddr, 296 unsigned long base) 297 { 298 return csum_ipv6_magic(saddr, daddr, len, IPPROTO_TCP, base); 299 } 300 301 static __u32 tcp_v6_init_sequence(struct sock *sk, struct sk_buff *skb) 302 { 303 if (skb->protocol == htons(ETH_P_IPV6)) { 304 return secure_tcpv6_sequence_number(skb->nh.ipv6h->daddr.s6_addr32, 305 skb->nh.ipv6h->saddr.s6_addr32, 306 skb->h.th->dest, 307 skb->h.th->source); 308 } else { 309 return secure_tcp_sequence_number(skb->nh.iph->daddr, 310 skb->nh.iph->saddr, 311 skb->h.th->dest, 312 skb->h.th->source); 313 } 314 } 315 316 static int __tcp_v6_check_established(struct sock *sk, const __u16 lport, 317 struct inet_timewait_sock **twp) 318 { 319 struct inet_sock *inet = inet_sk(sk); 320 const struct ipv6_pinfo *np = inet6_sk(sk); 321 const struct in6_addr *daddr = &np->rcv_saddr; 322 const struct in6_addr *saddr = &np->daddr; 323 const int dif = sk->sk_bound_dev_if; 324 const u32 ports = INET_COMBINED_PORTS(inet->dport, lport); 325 const int hash = inet6_ehashfn(daddr, inet->num, saddr, inet->dport, 326 tcp_hashinfo.ehash_size); 327 struct inet_ehash_bucket *head = &tcp_hashinfo.ehash[hash]; 328 struct sock *sk2; 329 const struct hlist_node *node; 330 struct inet_timewait_sock *tw; 331 332 write_lock(&head->lock); 333 334 /* Check TIME-WAIT sockets first. */ 335 sk_for_each(sk2, node, &(head + tcp_hashinfo.ehash_size)->chain) { 336 const struct tcp6_timewait_sock *tcp6tw = tcp6_twsk(sk2); 337 338 tw = inet_twsk(sk2); 339 340 if(*((__u32 *)&(tw->tw_dport)) == ports && 341 sk2->sk_family == PF_INET6 && 342 ipv6_addr_equal(&tcp6tw->tw_v6_daddr, saddr) && 343 ipv6_addr_equal(&tcp6tw->tw_v6_rcv_saddr, daddr) && 344 sk2->sk_bound_dev_if == sk->sk_bound_dev_if) { 345 const struct tcp_timewait_sock *tcptw = tcp_twsk(sk2); 346 struct tcp_sock *tp = tcp_sk(sk); 347 348 if (tcptw->tw_ts_recent_stamp && 349 (!twp || 350 (sysctl_tcp_tw_reuse && 351 xtime.tv_sec - tcptw->tw_ts_recent_stamp > 1))) { 352 /* See comment in tcp_ipv4.c */ 353 tp->write_seq = tcptw->tw_snd_nxt + 65535 + 2; 354 if (!tp->write_seq) 355 tp->write_seq = 1; 356 tp->rx_opt.ts_recent = tcptw->tw_ts_recent; 357 tp->rx_opt.ts_recent_stamp = tcptw->tw_ts_recent_stamp; 358 sock_hold(sk2); 359 goto unique; 360 } else 361 goto not_unique; 362 } 363 } 364 tw = NULL; 365 366 /* And established part... */ 367 sk_for_each(sk2, node, &head->chain) { 368 if (INET6_MATCH(sk2, saddr, daddr, ports, dif)) 369 goto not_unique; 370 } 371 372 unique: 373 BUG_TRAP(sk_unhashed(sk)); 374 __sk_add_node(sk, &head->chain); 375 sk->sk_hashent = hash; 376 sock_prot_inc_use(sk->sk_prot); 377 write_unlock(&head->lock); 378 379 if (twp) { 380 *twp = tw; 381 NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED); 382 } else if (tw) { 383 /* Silly. Should hash-dance instead... */ 384 inet_twsk_deschedule(tw, &tcp_death_row); 385 NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED); 386 387 inet_twsk_put(tw); 388 } 389 return 0; 390 391 not_unique: 392 write_unlock(&head->lock); 393 return -EADDRNOTAVAIL; 394 } 395 396 static inline u32 tcpv6_port_offset(const struct sock *sk) 397 { 398 const struct inet_sock *inet = inet_sk(sk); 399 const struct ipv6_pinfo *np = inet6_sk(sk); 400 401 return secure_tcpv6_port_ephemeral(np->rcv_saddr.s6_addr32, 402 np->daddr.s6_addr32, 403 inet->dport); 404 } 405 406 static int tcp_v6_hash_connect(struct sock *sk) 407 { 408 unsigned short snum = inet_sk(sk)->num; 409 struct inet_bind_hashbucket *head; 410 struct inet_bind_bucket *tb; 411 int ret; 412 413 if (!snum) { 414 int low = sysctl_local_port_range[0]; 415 int high = sysctl_local_port_range[1]; 416 int range = high - low; 417 int i; 418 int port; 419 static u32 hint; 420 u32 offset = hint + tcpv6_port_offset(sk); 421 struct hlist_node *node; 422 struct inet_timewait_sock *tw = NULL; 423 424 local_bh_disable(); 425 for (i = 1; i <= range; i++) { 426 port = low + (i + offset) % range; 427 head = &tcp_hashinfo.bhash[inet_bhashfn(port, tcp_hashinfo.bhash_size)]; 428 spin_lock(&head->lock); 429 430 /* Does not bother with rcv_saddr checks, 431 * because the established check is already 432 * unique enough. 433 */ 434 inet_bind_bucket_for_each(tb, node, &head->chain) { 435 if (tb->port == port) { 436 BUG_TRAP(!hlist_empty(&tb->owners)); 437 if (tb->fastreuse >= 0) 438 goto next_port; 439 if (!__tcp_v6_check_established(sk, 440 port, 441 &tw)) 442 goto ok; 443 goto next_port; 444 } 445 } 446 447 tb = inet_bind_bucket_create(tcp_hashinfo.bind_bucket_cachep, head, port); 448 if (!tb) { 449 spin_unlock(&head->lock); 450 break; 451 } 452 tb->fastreuse = -1; 453 goto ok; 454 455 next_port: 456 spin_unlock(&head->lock); 457 } 458 local_bh_enable(); 459 460 return -EADDRNOTAVAIL; 461 462 ok: 463 hint += i; 464 465 /* Head lock still held and bh's disabled */ 466 inet_bind_hash(sk, tb, port); 467 if (sk_unhashed(sk)) { 468 inet_sk(sk)->sport = htons(port); 469 __tcp_v6_hash(sk); 470 } 471 spin_unlock(&head->lock); 472 473 if (tw) { 474 inet_twsk_deschedule(tw, &tcp_death_row); 475 inet_twsk_put(tw); 476 } 477 478 ret = 0; 479 goto out; 480 } 481 482 head = &tcp_hashinfo.bhash[inet_bhashfn(snum, tcp_hashinfo.bhash_size)]; 483 tb = inet_csk(sk)->icsk_bind_hash; 484 spin_lock_bh(&head->lock); 485 486 if (sk_head(&tb->owners) == sk && !sk->sk_bind_node.next) { 487 __tcp_v6_hash(sk); 488 spin_unlock_bh(&head->lock); 489 return 0; 490 } else { 491 spin_unlock(&head->lock); 492 /* No definite answer... Walk to established hash table */ 493 ret = __tcp_v6_check_established(sk, snum, NULL); 494 out: 495 local_bh_enable(); 496 return ret; 497 } 498 } 499 500 static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr, 501 int addr_len) 502 { 503 struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr; 504 struct inet_sock *inet = inet_sk(sk); 505 struct ipv6_pinfo *np = inet6_sk(sk); 506 struct tcp_sock *tp = tcp_sk(sk); 507 struct in6_addr *saddr = NULL, *final_p = NULL, final; 508 struct flowi fl; 509 struct dst_entry *dst; 510 int addr_type; 511 int err; 512 513 if (addr_len < SIN6_LEN_RFC2133) 514 return -EINVAL; 515 516 if (usin->sin6_family != AF_INET6) 517 return(-EAFNOSUPPORT); 518 519 memset(&fl, 0, sizeof(fl)); 520 521 if (np->sndflow) { 522 fl.fl6_flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK; 523 IP6_ECN_flow_init(fl.fl6_flowlabel); 524 if (fl.fl6_flowlabel&IPV6_FLOWLABEL_MASK) { 525 struct ip6_flowlabel *flowlabel; 526 flowlabel = fl6_sock_lookup(sk, fl.fl6_flowlabel); 527 if (flowlabel == NULL) 528 return -EINVAL; 529 ipv6_addr_copy(&usin->sin6_addr, &flowlabel->dst); 530 fl6_sock_release(flowlabel); 531 } 532 } 533 534 /* 535 * connect() to INADDR_ANY means loopback (BSD'ism). 536 */ 537 538 if(ipv6_addr_any(&usin->sin6_addr)) 539 usin->sin6_addr.s6_addr[15] = 0x1; 540 541 addr_type = ipv6_addr_type(&usin->sin6_addr); 542 543 if(addr_type & IPV6_ADDR_MULTICAST) 544 return -ENETUNREACH; 545 546 if (addr_type&IPV6_ADDR_LINKLOCAL) { 547 if (addr_len >= sizeof(struct sockaddr_in6) && 548 usin->sin6_scope_id) { 549 /* If interface is set while binding, indices 550 * must coincide. 551 */ 552 if (sk->sk_bound_dev_if && 553 sk->sk_bound_dev_if != usin->sin6_scope_id) 554 return -EINVAL; 555 556 sk->sk_bound_dev_if = usin->sin6_scope_id; 557 } 558 559 /* Connect to link-local address requires an interface */ 560 if (!sk->sk_bound_dev_if) 561 return -EINVAL; 562 } 563 564 if (tp->rx_opt.ts_recent_stamp && 565 !ipv6_addr_equal(&np->daddr, &usin->sin6_addr)) { 566 tp->rx_opt.ts_recent = 0; 567 tp->rx_opt.ts_recent_stamp = 0; 568 tp->write_seq = 0; 569 } 570 571 ipv6_addr_copy(&np->daddr, &usin->sin6_addr); 572 np->flow_label = fl.fl6_flowlabel; 573 574 /* 575 * TCP over IPv4 576 */ 577 578 if (addr_type == IPV6_ADDR_MAPPED) { 579 u32 exthdrlen = tp->ext_header_len; 580 struct sockaddr_in sin; 581 582 SOCK_DEBUG(sk, "connect: ipv4 mapped\n"); 583 584 if (__ipv6_only_sock(sk)) 585 return -ENETUNREACH; 586 587 sin.sin_family = AF_INET; 588 sin.sin_port = usin->sin6_port; 589 sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3]; 590 591 tp->af_specific = &ipv6_mapped; 592 sk->sk_backlog_rcv = tcp_v4_do_rcv; 593 594 err = tcp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin)); 595 596 if (err) { 597 tp->ext_header_len = exthdrlen; 598 tp->af_specific = &ipv6_specific; 599 sk->sk_backlog_rcv = tcp_v6_do_rcv; 600 goto failure; 601 } else { 602 ipv6_addr_set(&np->saddr, 0, 0, htonl(0x0000FFFF), 603 inet->saddr); 604 ipv6_addr_set(&np->rcv_saddr, 0, 0, htonl(0x0000FFFF), 605 inet->rcv_saddr); 606 } 607 608 return err; 609 } 610 611 if (!ipv6_addr_any(&np->rcv_saddr)) 612 saddr = &np->rcv_saddr; 613 614 fl.proto = IPPROTO_TCP; 615 ipv6_addr_copy(&fl.fl6_dst, &np->daddr); 616 ipv6_addr_copy(&fl.fl6_src, 617 (saddr ? saddr : &np->saddr)); 618 fl.oif = sk->sk_bound_dev_if; 619 fl.fl_ip_dport = usin->sin6_port; 620 fl.fl_ip_sport = inet->sport; 621 622 if (np->opt && np->opt->srcrt) { 623 struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt; 624 ipv6_addr_copy(&final, &fl.fl6_dst); 625 ipv6_addr_copy(&fl.fl6_dst, rt0->addr); 626 final_p = &final; 627 } 628 629 err = ip6_dst_lookup(sk, &dst, &fl); 630 if (err) 631 goto failure; 632 if (final_p) 633 ipv6_addr_copy(&fl.fl6_dst, final_p); 634 635 if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) 636 goto failure; 637 638 if (saddr == NULL) { 639 saddr = &fl.fl6_src; 640 ipv6_addr_copy(&np->rcv_saddr, saddr); 641 } 642 643 /* set the source address */ 644 ipv6_addr_copy(&np->saddr, saddr); 645 inet->rcv_saddr = LOOPBACK4_IPV6; 646 647 ip6_dst_store(sk, dst, NULL); 648 sk->sk_route_caps = dst->dev->features & 649 ~(NETIF_F_IP_CSUM | NETIF_F_TSO); 650 651 tp->ext_header_len = 0; 652 if (np->opt) 653 tp->ext_header_len = np->opt->opt_flen + np->opt->opt_nflen; 654 655 tp->rx_opt.mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - sizeof(struct ipv6hdr); 656 657 inet->dport = usin->sin6_port; 658 659 tcp_set_state(sk, TCP_SYN_SENT); 660 err = tcp_v6_hash_connect(sk); 661 if (err) 662 goto late_failure; 663 664 if (!tp->write_seq) 665 tp->write_seq = secure_tcpv6_sequence_number(np->saddr.s6_addr32, 666 np->daddr.s6_addr32, 667 inet->sport, 668 inet->dport); 669 670 err = tcp_connect(sk); 671 if (err) 672 goto late_failure; 673 674 return 0; 675 676 late_failure: 677 tcp_set_state(sk, TCP_CLOSE); 678 __sk_dst_reset(sk); 679 failure: 680 inet->dport = 0; 681 sk->sk_route_caps = 0; 682 return err; 683 } 684 685 static void tcp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 686 int type, int code, int offset, __u32 info) 687 { 688 struct ipv6hdr *hdr = (struct ipv6hdr*)skb->data; 689 const struct tcphdr *th = (struct tcphdr *)(skb->data+offset); 690 struct ipv6_pinfo *np; 691 struct sock *sk; 692 int err; 693 struct tcp_sock *tp; 694 __u32 seq; 695 696 sk = inet6_lookup(&tcp_hashinfo, &hdr->daddr, th->dest, &hdr->saddr, 697 th->source, skb->dev->ifindex); 698 699 if (sk == NULL) { 700 ICMP6_INC_STATS_BH(__in6_dev_get(skb->dev), ICMP6_MIB_INERRORS); 701 return; 702 } 703 704 if (sk->sk_state == TCP_TIME_WAIT) { 705 inet_twsk_put((struct inet_timewait_sock *)sk); 706 return; 707 } 708 709 bh_lock_sock(sk); 710 if (sock_owned_by_user(sk)) 711 NET_INC_STATS_BH(LINUX_MIB_LOCKDROPPEDICMPS); 712 713 if (sk->sk_state == TCP_CLOSE) 714 goto out; 715 716 tp = tcp_sk(sk); 717 seq = ntohl(th->seq); 718 if (sk->sk_state != TCP_LISTEN && 719 !between(seq, tp->snd_una, tp->snd_nxt)) { 720 NET_INC_STATS_BH(LINUX_MIB_OUTOFWINDOWICMPS); 721 goto out; 722 } 723 724 np = inet6_sk(sk); 725 726 if (type == ICMPV6_PKT_TOOBIG) { 727 struct dst_entry *dst = NULL; 728 729 if (sock_owned_by_user(sk)) 730 goto out; 731 if ((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) 732 goto out; 733 734 /* icmp should have updated the destination cache entry */ 735 dst = __sk_dst_check(sk, np->dst_cookie); 736 737 if (dst == NULL) { 738 struct inet_sock *inet = inet_sk(sk); 739 struct flowi fl; 740 741 /* BUGGG_FUTURE: Again, it is not clear how 742 to handle rthdr case. Ignore this complexity 743 for now. 744 */ 745 memset(&fl, 0, sizeof(fl)); 746 fl.proto = IPPROTO_TCP; 747 ipv6_addr_copy(&fl.fl6_dst, &np->daddr); 748 ipv6_addr_copy(&fl.fl6_src, &np->saddr); 749 fl.oif = sk->sk_bound_dev_if; 750 fl.fl_ip_dport = inet->dport; 751 fl.fl_ip_sport = inet->sport; 752 753 if ((err = ip6_dst_lookup(sk, &dst, &fl))) { 754 sk->sk_err_soft = -err; 755 goto out; 756 } 757 758 if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) { 759 sk->sk_err_soft = -err; 760 goto out; 761 } 762 763 } else 764 dst_hold(dst); 765 766 if (tp->pmtu_cookie > dst_mtu(dst)) { 767 tcp_sync_mss(sk, dst_mtu(dst)); 768 tcp_simple_retransmit(sk); 769 } /* else let the usual retransmit timer handle it */ 770 dst_release(dst); 771 goto out; 772 } 773 774 icmpv6_err_convert(type, code, &err); 775 776 /* Might be for an request_sock */ 777 switch (sk->sk_state) { 778 struct request_sock *req, **prev; 779 case TCP_LISTEN: 780 if (sock_owned_by_user(sk)) 781 goto out; 782 783 req = tcp_v6_search_req(sk, &prev, th->dest, &hdr->daddr, 784 &hdr->saddr, inet6_iif(skb)); 785 if (!req) 786 goto out; 787 788 /* ICMPs are not backlogged, hence we cannot get 789 * an established socket here. 790 */ 791 BUG_TRAP(req->sk == NULL); 792 793 if (seq != tcp_rsk(req)->snt_isn) { 794 NET_INC_STATS_BH(LINUX_MIB_OUTOFWINDOWICMPS); 795 goto out; 796 } 797 798 inet_csk_reqsk_queue_drop(sk, req, prev); 799 goto out; 800 801 case TCP_SYN_SENT: 802 case TCP_SYN_RECV: /* Cannot happen. 803 It can, it SYNs are crossed. --ANK */ 804 if (!sock_owned_by_user(sk)) { 805 TCP_INC_STATS_BH(TCP_MIB_ATTEMPTFAILS); 806 sk->sk_err = err; 807 sk->sk_error_report(sk); /* Wake people up to see the error (see connect in sock.c) */ 808 809 tcp_done(sk); 810 } else 811 sk->sk_err_soft = err; 812 goto out; 813 } 814 815 if (!sock_owned_by_user(sk) && np->recverr) { 816 sk->sk_err = err; 817 sk->sk_error_report(sk); 818 } else 819 sk->sk_err_soft = err; 820 821 out: 822 bh_unlock_sock(sk); 823 sock_put(sk); 824 } 825 826 827 static int tcp_v6_send_synack(struct sock *sk, struct request_sock *req, 828 struct dst_entry *dst) 829 { 830 struct tcp6_request_sock *treq = tcp6_rsk(req); 831 struct ipv6_pinfo *np = inet6_sk(sk); 832 struct sk_buff * skb; 833 struct ipv6_txoptions *opt = NULL; 834 struct in6_addr * final_p = NULL, final; 835 struct flowi fl; 836 int err = -1; 837 838 memset(&fl, 0, sizeof(fl)); 839 fl.proto = IPPROTO_TCP; 840 ipv6_addr_copy(&fl.fl6_dst, &treq->rmt_addr); 841 ipv6_addr_copy(&fl.fl6_src, &treq->loc_addr); 842 fl.fl6_flowlabel = 0; 843 fl.oif = treq->iif; 844 fl.fl_ip_dport = inet_rsk(req)->rmt_port; 845 fl.fl_ip_sport = inet_sk(sk)->sport; 846 847 if (dst == NULL) { 848 opt = np->opt; 849 if (opt == NULL && 850 np->rxopt.bits.osrcrt == 2 && 851 treq->pktopts) { 852 struct sk_buff *pktopts = treq->pktopts; 853 struct inet6_skb_parm *rxopt = IP6CB(pktopts); 854 if (rxopt->srcrt) 855 opt = ipv6_invert_rthdr(sk, (struct ipv6_rt_hdr*)(pktopts->nh.raw + rxopt->srcrt)); 856 } 857 858 if (opt && opt->srcrt) { 859 struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt; 860 ipv6_addr_copy(&final, &fl.fl6_dst); 861 ipv6_addr_copy(&fl.fl6_dst, rt0->addr); 862 final_p = &final; 863 } 864 865 err = ip6_dst_lookup(sk, &dst, &fl); 866 if (err) 867 goto done; 868 if (final_p) 869 ipv6_addr_copy(&fl.fl6_dst, final_p); 870 if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) 871 goto done; 872 } 873 874 skb = tcp_make_synack(sk, dst, req); 875 if (skb) { 876 struct tcphdr *th = skb->h.th; 877 878 th->check = tcp_v6_check(th, skb->len, 879 &treq->loc_addr, &treq->rmt_addr, 880 csum_partial((char *)th, skb->len, skb->csum)); 881 882 ipv6_addr_copy(&fl.fl6_dst, &treq->rmt_addr); 883 err = ip6_xmit(sk, skb, &fl, opt, 0); 884 if (err == NET_XMIT_CN) 885 err = 0; 886 } 887 888 done: 889 if (opt && opt != np->opt) 890 sock_kfree_s(sk, opt, opt->tot_len); 891 return err; 892 } 893 894 static void tcp_v6_reqsk_destructor(struct request_sock *req) 895 { 896 if (tcp6_rsk(req)->pktopts) 897 kfree_skb(tcp6_rsk(req)->pktopts); 898 } 899 900 static struct request_sock_ops tcp6_request_sock_ops = { 901 .family = AF_INET6, 902 .obj_size = sizeof(struct tcp6_request_sock), 903 .rtx_syn_ack = tcp_v6_send_synack, 904 .send_ack = tcp_v6_reqsk_send_ack, 905 .destructor = tcp_v6_reqsk_destructor, 906 .send_reset = tcp_v6_send_reset 907 }; 908 909 static int ipv6_opt_accepted(struct sock *sk, struct sk_buff *skb) 910 { 911 struct ipv6_pinfo *np = inet6_sk(sk); 912 struct inet6_skb_parm *opt = IP6CB(skb); 913 914 if (np->rxopt.all) { 915 if ((opt->hop && (np->rxopt.bits.hopopts || np->rxopt.bits.ohopopts)) || 916 ((IPV6_FLOWINFO_MASK & *(u32*)skb->nh.raw) && np->rxopt.bits.rxflow) || 917 (opt->srcrt && (np->rxopt.bits.srcrt || np->rxopt.bits.osrcrt)) || 918 ((opt->dst1 || opt->dst0) && (np->rxopt.bits.dstopts || np->rxopt.bits.odstopts))) 919 return 1; 920 } 921 return 0; 922 } 923 924 925 static void tcp_v6_send_check(struct sock *sk, struct tcphdr *th, int len, 926 struct sk_buff *skb) 927 { 928 struct ipv6_pinfo *np = inet6_sk(sk); 929 930 if (skb->ip_summed == CHECKSUM_HW) { 931 th->check = ~csum_ipv6_magic(&np->saddr, &np->daddr, len, IPPROTO_TCP, 0); 932 skb->csum = offsetof(struct tcphdr, check); 933 } else { 934 th->check = csum_ipv6_magic(&np->saddr, &np->daddr, len, IPPROTO_TCP, 935 csum_partial((char *)th, th->doff<<2, 936 skb->csum)); 937 } 938 } 939 940 941 static void tcp_v6_send_reset(struct sk_buff *skb) 942 { 943 struct tcphdr *th = skb->h.th, *t1; 944 struct sk_buff *buff; 945 struct flowi fl; 946 947 if (th->rst) 948 return; 949 950 if (!ipv6_unicast_destination(skb)) 951 return; 952 953 /* 954 * We need to grab some memory, and put together an RST, 955 * and then put it into the queue to be sent. 956 */ 957 958 buff = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + sizeof(struct tcphdr), 959 GFP_ATOMIC); 960 if (buff == NULL) 961 return; 962 963 skb_reserve(buff, MAX_HEADER + sizeof(struct ipv6hdr) + sizeof(struct tcphdr)); 964 965 t1 = (struct tcphdr *) skb_push(buff,sizeof(struct tcphdr)); 966 967 /* Swap the send and the receive. */ 968 memset(t1, 0, sizeof(*t1)); 969 t1->dest = th->source; 970 t1->source = th->dest; 971 t1->doff = sizeof(*t1)/4; 972 t1->rst = 1; 973 974 if(th->ack) { 975 t1->seq = th->ack_seq; 976 } else { 977 t1->ack = 1; 978 t1->ack_seq = htonl(ntohl(th->seq) + th->syn + th->fin 979 + skb->len - (th->doff<<2)); 980 } 981 982 buff->csum = csum_partial((char *)t1, sizeof(*t1), 0); 983 984 memset(&fl, 0, sizeof(fl)); 985 ipv6_addr_copy(&fl.fl6_dst, &skb->nh.ipv6h->saddr); 986 ipv6_addr_copy(&fl.fl6_src, &skb->nh.ipv6h->daddr); 987 988 t1->check = csum_ipv6_magic(&fl.fl6_src, &fl.fl6_dst, 989 sizeof(*t1), IPPROTO_TCP, 990 buff->csum); 991 992 fl.proto = IPPROTO_TCP; 993 fl.oif = inet6_iif(skb); 994 fl.fl_ip_dport = t1->dest; 995 fl.fl_ip_sport = t1->source; 996 997 /* sk = NULL, but it is safe for now. RST socket required. */ 998 if (!ip6_dst_lookup(NULL, &buff->dst, &fl)) { 999 1000 if ((xfrm_lookup(&buff->dst, &fl, NULL, 0)) < 0) 1001 return; 1002 1003 ip6_xmit(NULL, buff, &fl, NULL, 0); 1004 TCP_INC_STATS_BH(TCP_MIB_OUTSEGS); 1005 TCP_INC_STATS_BH(TCP_MIB_OUTRSTS); 1006 return; 1007 } 1008 1009 kfree_skb(buff); 1010 } 1011 1012 static void tcp_v6_send_ack(struct sk_buff *skb, u32 seq, u32 ack, u32 win, u32 ts) 1013 { 1014 struct tcphdr *th = skb->h.th, *t1; 1015 struct sk_buff *buff; 1016 struct flowi fl; 1017 int tot_len = sizeof(struct tcphdr); 1018 1019 if (ts) 1020 tot_len += 3*4; 1021 1022 buff = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + tot_len, 1023 GFP_ATOMIC); 1024 if (buff == NULL) 1025 return; 1026 1027 skb_reserve(buff, MAX_HEADER + sizeof(struct ipv6hdr) + tot_len); 1028 1029 t1 = (struct tcphdr *) skb_push(buff,tot_len); 1030 1031 /* Swap the send and the receive. */ 1032 memset(t1, 0, sizeof(*t1)); 1033 t1->dest = th->source; 1034 t1->source = th->dest; 1035 t1->doff = tot_len/4; 1036 t1->seq = htonl(seq); 1037 t1->ack_seq = htonl(ack); 1038 t1->ack = 1; 1039 t1->window = htons(win); 1040 1041 if (ts) { 1042 u32 *ptr = (u32*)(t1 + 1); 1043 *ptr++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | 1044 (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP); 1045 *ptr++ = htonl(tcp_time_stamp); 1046 *ptr = htonl(ts); 1047 } 1048 1049 buff->csum = csum_partial((char *)t1, tot_len, 0); 1050 1051 memset(&fl, 0, sizeof(fl)); 1052 ipv6_addr_copy(&fl.fl6_dst, &skb->nh.ipv6h->saddr); 1053 ipv6_addr_copy(&fl.fl6_src, &skb->nh.ipv6h->daddr); 1054 1055 t1->check = csum_ipv6_magic(&fl.fl6_src, &fl.fl6_dst, 1056 tot_len, IPPROTO_TCP, 1057 buff->csum); 1058 1059 fl.proto = IPPROTO_TCP; 1060 fl.oif = inet6_iif(skb); 1061 fl.fl_ip_dport = t1->dest; 1062 fl.fl_ip_sport = t1->source; 1063 1064 if (!ip6_dst_lookup(NULL, &buff->dst, &fl)) { 1065 if ((xfrm_lookup(&buff->dst, &fl, NULL, 0)) < 0) 1066 return; 1067 ip6_xmit(NULL, buff, &fl, NULL, 0); 1068 TCP_INC_STATS_BH(TCP_MIB_OUTSEGS); 1069 return; 1070 } 1071 1072 kfree_skb(buff); 1073 } 1074 1075 static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb) 1076 { 1077 struct inet_timewait_sock *tw = inet_twsk(sk); 1078 const struct tcp_timewait_sock *tcptw = tcp_twsk(sk); 1079 1080 tcp_v6_send_ack(skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt, 1081 tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale, 1082 tcptw->tw_ts_recent); 1083 1084 inet_twsk_put(tw); 1085 } 1086 1087 static void tcp_v6_reqsk_send_ack(struct sk_buff *skb, struct request_sock *req) 1088 { 1089 tcp_v6_send_ack(skb, tcp_rsk(req)->snt_isn + 1, tcp_rsk(req)->rcv_isn + 1, req->rcv_wnd, req->ts_recent); 1090 } 1091 1092 1093 static struct sock *tcp_v6_hnd_req(struct sock *sk,struct sk_buff *skb) 1094 { 1095 struct request_sock *req, **prev; 1096 const struct tcphdr *th = skb->h.th; 1097 struct sock *nsk; 1098 1099 /* Find possible connection requests. */ 1100 req = tcp_v6_search_req(sk, &prev, th->source, &skb->nh.ipv6h->saddr, 1101 &skb->nh.ipv6h->daddr, inet6_iif(skb)); 1102 if (req) 1103 return tcp_check_req(sk, skb, req, prev); 1104 1105 nsk = __inet6_lookup_established(&tcp_hashinfo, &skb->nh.ipv6h->saddr, 1106 th->source, &skb->nh.ipv6h->daddr, 1107 ntohs(th->dest), inet6_iif(skb)); 1108 1109 if (nsk) { 1110 if (nsk->sk_state != TCP_TIME_WAIT) { 1111 bh_lock_sock(nsk); 1112 return nsk; 1113 } 1114 inet_twsk_put((struct inet_timewait_sock *)nsk); 1115 return NULL; 1116 } 1117 1118 #if 0 /*def CONFIG_SYN_COOKIES*/ 1119 if (!th->rst && !th->syn && th->ack) 1120 sk = cookie_v6_check(sk, skb, &(IPCB(skb)->opt)); 1121 #endif 1122 return sk; 1123 } 1124 1125 static void tcp_v6_synq_add(struct sock *sk, struct request_sock *req) 1126 { 1127 struct inet_connection_sock *icsk = inet_csk(sk); 1128 struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt; 1129 const u32 h = tcp_v6_synq_hash(&tcp6_rsk(req)->rmt_addr, inet_rsk(req)->rmt_port, lopt->hash_rnd); 1130 1131 reqsk_queue_hash_req(&icsk->icsk_accept_queue, h, req, TCP_TIMEOUT_INIT); 1132 inet_csk_reqsk_queue_added(sk, TCP_TIMEOUT_INIT); 1133 } 1134 1135 1136 /* FIXME: this is substantially similar to the ipv4 code. 1137 * Can some kind of merge be done? -- erics 1138 */ 1139 static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb) 1140 { 1141 struct tcp6_request_sock *treq; 1142 struct ipv6_pinfo *np = inet6_sk(sk); 1143 struct tcp_options_received tmp_opt; 1144 struct tcp_sock *tp = tcp_sk(sk); 1145 struct request_sock *req = NULL; 1146 __u32 isn = TCP_SKB_CB(skb)->when; 1147 1148 if (skb->protocol == htons(ETH_P_IP)) 1149 return tcp_v4_conn_request(sk, skb); 1150 1151 if (!ipv6_unicast_destination(skb)) 1152 goto drop; 1153 1154 /* 1155 * There are no SYN attacks on IPv6, yet... 1156 */ 1157 if (inet_csk_reqsk_queue_is_full(sk) && !isn) { 1158 if (net_ratelimit()) 1159 printk(KERN_INFO "TCPv6: dropping request, synflood is possible\n"); 1160 goto drop; 1161 } 1162 1163 if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1) 1164 goto drop; 1165 1166 req = reqsk_alloc(&tcp6_request_sock_ops); 1167 if (req == NULL) 1168 goto drop; 1169 1170 tcp_clear_options(&tmp_opt); 1171 tmp_opt.mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - sizeof(struct ipv6hdr); 1172 tmp_opt.user_mss = tp->rx_opt.user_mss; 1173 1174 tcp_parse_options(skb, &tmp_opt, 0); 1175 1176 tmp_opt.tstamp_ok = tmp_opt.saw_tstamp; 1177 tcp_openreq_init(req, &tmp_opt, skb); 1178 1179 treq = tcp6_rsk(req); 1180 ipv6_addr_copy(&treq->rmt_addr, &skb->nh.ipv6h->saddr); 1181 ipv6_addr_copy(&treq->loc_addr, &skb->nh.ipv6h->daddr); 1182 TCP_ECN_create_request(req, skb->h.th); 1183 treq->pktopts = NULL; 1184 if (ipv6_opt_accepted(sk, skb) || 1185 np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo || 1186 np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) { 1187 atomic_inc(&skb->users); 1188 treq->pktopts = skb; 1189 } 1190 treq->iif = sk->sk_bound_dev_if; 1191 1192 /* So that link locals have meaning */ 1193 if (!sk->sk_bound_dev_if && 1194 ipv6_addr_type(&treq->rmt_addr) & IPV6_ADDR_LINKLOCAL) 1195 treq->iif = inet6_iif(skb); 1196 1197 if (isn == 0) 1198 isn = tcp_v6_init_sequence(sk,skb); 1199 1200 tcp_rsk(req)->snt_isn = isn; 1201 1202 if (tcp_v6_send_synack(sk, req, NULL)) 1203 goto drop; 1204 1205 tcp_v6_synq_add(sk, req); 1206 1207 return 0; 1208 1209 drop: 1210 if (req) 1211 reqsk_free(req); 1212 1213 TCP_INC_STATS_BH(TCP_MIB_ATTEMPTFAILS); 1214 return 0; /* don't send reset */ 1215 } 1216 1217 static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb, 1218 struct request_sock *req, 1219 struct dst_entry *dst) 1220 { 1221 struct tcp6_request_sock *treq = tcp6_rsk(req); 1222 struct ipv6_pinfo *newnp, *np = inet6_sk(sk); 1223 struct tcp6_sock *newtcp6sk; 1224 struct inet_sock *newinet; 1225 struct tcp_sock *newtp; 1226 struct sock *newsk; 1227 struct ipv6_txoptions *opt; 1228 1229 if (skb->protocol == htons(ETH_P_IP)) { 1230 /* 1231 * v6 mapped 1232 */ 1233 1234 newsk = tcp_v4_syn_recv_sock(sk, skb, req, dst); 1235 1236 if (newsk == NULL) 1237 return NULL; 1238 1239 newtcp6sk = (struct tcp6_sock *)newsk; 1240 inet_sk(newsk)->pinet6 = &newtcp6sk->inet6; 1241 1242 newinet = inet_sk(newsk); 1243 newnp = inet6_sk(newsk); 1244 newtp = tcp_sk(newsk); 1245 1246 memcpy(newnp, np, sizeof(struct ipv6_pinfo)); 1247 1248 ipv6_addr_set(&newnp->daddr, 0, 0, htonl(0x0000FFFF), 1249 newinet->daddr); 1250 1251 ipv6_addr_set(&newnp->saddr, 0, 0, htonl(0x0000FFFF), 1252 newinet->saddr); 1253 1254 ipv6_addr_copy(&newnp->rcv_saddr, &newnp->saddr); 1255 1256 newtp->af_specific = &ipv6_mapped; 1257 newsk->sk_backlog_rcv = tcp_v4_do_rcv; 1258 newnp->pktoptions = NULL; 1259 newnp->opt = NULL; 1260 newnp->mcast_oif = inet6_iif(skb); 1261 newnp->mcast_hops = skb->nh.ipv6h->hop_limit; 1262 1263 /* 1264 * No need to charge this sock to the relevant IPv6 refcnt debug socks count 1265 * here, tcp_create_openreq_child now does this for us, see the comment in 1266 * that function for the gory details. -acme 1267 */ 1268 1269 /* It is tricky place. Until this moment IPv4 tcp 1270 worked with IPv6 af_tcp.af_specific. 1271 Sync it now. 1272 */ 1273 tcp_sync_mss(newsk, newtp->pmtu_cookie); 1274 1275 return newsk; 1276 } 1277 1278 opt = np->opt; 1279 1280 if (sk_acceptq_is_full(sk)) 1281 goto out_overflow; 1282 1283 if (np->rxopt.bits.osrcrt == 2 && 1284 opt == NULL && treq->pktopts) { 1285 struct inet6_skb_parm *rxopt = IP6CB(treq->pktopts); 1286 if (rxopt->srcrt) 1287 opt = ipv6_invert_rthdr(sk, (struct ipv6_rt_hdr *)(treq->pktopts->nh.raw + rxopt->srcrt)); 1288 } 1289 1290 if (dst == NULL) { 1291 struct in6_addr *final_p = NULL, final; 1292 struct flowi fl; 1293 1294 memset(&fl, 0, sizeof(fl)); 1295 fl.proto = IPPROTO_TCP; 1296 ipv6_addr_copy(&fl.fl6_dst, &treq->rmt_addr); 1297 if (opt && opt->srcrt) { 1298 struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt; 1299 ipv6_addr_copy(&final, &fl.fl6_dst); 1300 ipv6_addr_copy(&fl.fl6_dst, rt0->addr); 1301 final_p = &final; 1302 } 1303 ipv6_addr_copy(&fl.fl6_src, &treq->loc_addr); 1304 fl.oif = sk->sk_bound_dev_if; 1305 fl.fl_ip_dport = inet_rsk(req)->rmt_port; 1306 fl.fl_ip_sport = inet_sk(sk)->sport; 1307 1308 if (ip6_dst_lookup(sk, &dst, &fl)) 1309 goto out; 1310 1311 if (final_p) 1312 ipv6_addr_copy(&fl.fl6_dst, final_p); 1313 1314 if ((xfrm_lookup(&dst, &fl, sk, 0)) < 0) 1315 goto out; 1316 } 1317 1318 newsk = tcp_create_openreq_child(sk, req, skb); 1319 if (newsk == NULL) 1320 goto out; 1321 1322 /* 1323 * No need to charge this sock to the relevant IPv6 refcnt debug socks 1324 * count here, tcp_create_openreq_child now does this for us, see the 1325 * comment in that function for the gory details. -acme 1326 */ 1327 1328 ip6_dst_store(newsk, dst, NULL); 1329 newsk->sk_route_caps = dst->dev->features & 1330 ~(NETIF_F_IP_CSUM | NETIF_F_TSO); 1331 1332 newtcp6sk = (struct tcp6_sock *)newsk; 1333 inet_sk(newsk)->pinet6 = &newtcp6sk->inet6; 1334 1335 newtp = tcp_sk(newsk); 1336 newinet = inet_sk(newsk); 1337 newnp = inet6_sk(newsk); 1338 1339 memcpy(newnp, np, sizeof(struct ipv6_pinfo)); 1340 1341 ipv6_addr_copy(&newnp->daddr, &treq->rmt_addr); 1342 ipv6_addr_copy(&newnp->saddr, &treq->loc_addr); 1343 ipv6_addr_copy(&newnp->rcv_saddr, &treq->loc_addr); 1344 newsk->sk_bound_dev_if = treq->iif; 1345 1346 /* Now IPv6 options... 1347 1348 First: no IPv4 options. 1349 */ 1350 newinet->opt = NULL; 1351 1352 /* Clone RX bits */ 1353 newnp->rxopt.all = np->rxopt.all; 1354 1355 /* Clone pktoptions received with SYN */ 1356 newnp->pktoptions = NULL; 1357 if (treq->pktopts != NULL) { 1358 newnp->pktoptions = skb_clone(treq->pktopts, GFP_ATOMIC); 1359 kfree_skb(treq->pktopts); 1360 treq->pktopts = NULL; 1361 if (newnp->pktoptions) 1362 skb_set_owner_r(newnp->pktoptions, newsk); 1363 } 1364 newnp->opt = NULL; 1365 newnp->mcast_oif = inet6_iif(skb); 1366 newnp->mcast_hops = skb->nh.ipv6h->hop_limit; 1367 1368 /* Clone native IPv6 options from listening socket (if any) 1369 1370 Yes, keeping reference count would be much more clever, 1371 but we make one more one thing there: reattach optmem 1372 to newsk. 1373 */ 1374 if (opt) { 1375 newnp->opt = ipv6_dup_options(newsk, opt); 1376 if (opt != np->opt) 1377 sock_kfree_s(sk, opt, opt->tot_len); 1378 } 1379 1380 newtp->ext_header_len = 0; 1381 if (newnp->opt) 1382 newtp->ext_header_len = newnp->opt->opt_nflen + 1383 newnp->opt->opt_flen; 1384 1385 tcp_sync_mss(newsk, dst_mtu(dst)); 1386 newtp->advmss = dst_metric(dst, RTAX_ADVMSS); 1387 tcp_initialize_rcv_mss(newsk); 1388 1389 newinet->daddr = newinet->saddr = newinet->rcv_saddr = LOOPBACK4_IPV6; 1390 1391 __tcp_v6_hash(newsk); 1392 inet_inherit_port(&tcp_hashinfo, sk, newsk); 1393 1394 return newsk; 1395 1396 out_overflow: 1397 NET_INC_STATS_BH(LINUX_MIB_LISTENOVERFLOWS); 1398 out: 1399 NET_INC_STATS_BH(LINUX_MIB_LISTENDROPS); 1400 if (opt && opt != np->opt) 1401 sock_kfree_s(sk, opt, opt->tot_len); 1402 dst_release(dst); 1403 return NULL; 1404 } 1405 1406 static int tcp_v6_checksum_init(struct sk_buff *skb) 1407 { 1408 if (skb->ip_summed == CHECKSUM_HW) { 1409 skb->ip_summed = CHECKSUM_UNNECESSARY; 1410 if (!tcp_v6_check(skb->h.th,skb->len,&skb->nh.ipv6h->saddr, 1411 &skb->nh.ipv6h->daddr,skb->csum)) 1412 return 0; 1413 LIMIT_NETDEBUG(KERN_DEBUG "hw tcp v6 csum failed\n"); 1414 } 1415 if (skb->len <= 76) { 1416 if (tcp_v6_check(skb->h.th,skb->len,&skb->nh.ipv6h->saddr, 1417 &skb->nh.ipv6h->daddr,skb_checksum(skb, 0, skb->len, 0))) 1418 return -1; 1419 skb->ip_summed = CHECKSUM_UNNECESSARY; 1420 } else { 1421 skb->csum = ~tcp_v6_check(skb->h.th,skb->len,&skb->nh.ipv6h->saddr, 1422 &skb->nh.ipv6h->daddr,0); 1423 } 1424 return 0; 1425 } 1426 1427 /* The socket must have it's spinlock held when we get 1428 * here. 1429 * 1430 * We have a potential double-lock case here, so even when 1431 * doing backlog processing we use the BH locking scheme. 1432 * This is because we cannot sleep with the original spinlock 1433 * held. 1434 */ 1435 static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) 1436 { 1437 struct ipv6_pinfo *np = inet6_sk(sk); 1438 struct tcp_sock *tp; 1439 struct sk_buff *opt_skb = NULL; 1440 1441 /* Imagine: socket is IPv6. IPv4 packet arrives, 1442 goes to IPv4 receive handler and backlogged. 1443 From backlog it always goes here. Kerboom... 1444 Fortunately, tcp_rcv_established and rcv_established 1445 handle them correctly, but it is not case with 1446 tcp_v6_hnd_req and tcp_v6_send_reset(). --ANK 1447 */ 1448 1449 if (skb->protocol == htons(ETH_P_IP)) 1450 return tcp_v4_do_rcv(sk, skb); 1451 1452 if (sk_filter(sk, skb, 0)) 1453 goto discard; 1454 1455 /* 1456 * socket locking is here for SMP purposes as backlog rcv 1457 * is currently called with bh processing disabled. 1458 */ 1459 1460 /* Do Stevens' IPV6_PKTOPTIONS. 1461 1462 Yes, guys, it is the only place in our code, where we 1463 may make it not affecting IPv4. 1464 The rest of code is protocol independent, 1465 and I do not like idea to uglify IPv4. 1466 1467 Actually, all the idea behind IPV6_PKTOPTIONS 1468 looks not very well thought. For now we latch 1469 options, received in the last packet, enqueued 1470 by tcp. Feel free to propose better solution. 1471 --ANK (980728) 1472 */ 1473 if (np->rxopt.all) 1474 opt_skb = skb_clone(skb, GFP_ATOMIC); 1475 1476 if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */ 1477 TCP_CHECK_TIMER(sk); 1478 if (tcp_rcv_established(sk, skb, skb->h.th, skb->len)) 1479 goto reset; 1480 TCP_CHECK_TIMER(sk); 1481 if (opt_skb) 1482 goto ipv6_pktoptions; 1483 return 0; 1484 } 1485 1486 if (skb->len < (skb->h.th->doff<<2) || tcp_checksum_complete(skb)) 1487 goto csum_err; 1488 1489 if (sk->sk_state == TCP_LISTEN) { 1490 struct sock *nsk = tcp_v6_hnd_req(sk, skb); 1491 if (!nsk) 1492 goto discard; 1493 1494 /* 1495 * Queue it on the new socket if the new socket is active, 1496 * otherwise we just shortcircuit this and continue with 1497 * the new socket.. 1498 */ 1499 if(nsk != sk) { 1500 if (tcp_child_process(sk, nsk, skb)) 1501 goto reset; 1502 if (opt_skb) 1503 __kfree_skb(opt_skb); 1504 return 0; 1505 } 1506 } 1507 1508 TCP_CHECK_TIMER(sk); 1509 if (tcp_rcv_state_process(sk, skb, skb->h.th, skb->len)) 1510 goto reset; 1511 TCP_CHECK_TIMER(sk); 1512 if (opt_skb) 1513 goto ipv6_pktoptions; 1514 return 0; 1515 1516 reset: 1517 tcp_v6_send_reset(skb); 1518 discard: 1519 if (opt_skb) 1520 __kfree_skb(opt_skb); 1521 kfree_skb(skb); 1522 return 0; 1523 csum_err: 1524 TCP_INC_STATS_BH(TCP_MIB_INERRS); 1525 goto discard; 1526 1527 1528 ipv6_pktoptions: 1529 /* Do you ask, what is it? 1530 1531 1. skb was enqueued by tcp. 1532 2. skb is added to tail of read queue, rather than out of order. 1533 3. socket is not in passive state. 1534 4. Finally, it really contains options, which user wants to receive. 1535 */ 1536 tp = tcp_sk(sk); 1537 if (TCP_SKB_CB(opt_skb)->end_seq == tp->rcv_nxt && 1538 !((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))) { 1539 if (np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo) 1540 np->mcast_oif = inet6_iif(opt_skb); 1541 if (np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) 1542 np->mcast_hops = opt_skb->nh.ipv6h->hop_limit; 1543 if (ipv6_opt_accepted(sk, opt_skb)) { 1544 skb_set_owner_r(opt_skb, sk); 1545 opt_skb = xchg(&np->pktoptions, opt_skb); 1546 } else { 1547 __kfree_skb(opt_skb); 1548 opt_skb = xchg(&np->pktoptions, NULL); 1549 } 1550 } 1551 1552 if (opt_skb) 1553 kfree_skb(opt_skb); 1554 return 0; 1555 } 1556 1557 static int tcp_v6_rcv(struct sk_buff **pskb, unsigned int *nhoffp) 1558 { 1559 struct sk_buff *skb = *pskb; 1560 struct tcphdr *th; 1561 struct sock *sk; 1562 int ret; 1563 1564 if (skb->pkt_type != PACKET_HOST) 1565 goto discard_it; 1566 1567 /* 1568 * Count it even if it's bad. 1569 */ 1570 TCP_INC_STATS_BH(TCP_MIB_INSEGS); 1571 1572 if (!pskb_may_pull(skb, sizeof(struct tcphdr))) 1573 goto discard_it; 1574 1575 th = skb->h.th; 1576 1577 if (th->doff < sizeof(struct tcphdr)/4) 1578 goto bad_packet; 1579 if (!pskb_may_pull(skb, th->doff*4)) 1580 goto discard_it; 1581 1582 if ((skb->ip_summed != CHECKSUM_UNNECESSARY && 1583 tcp_v6_checksum_init(skb) < 0)) 1584 goto bad_packet; 1585 1586 th = skb->h.th; 1587 TCP_SKB_CB(skb)->seq = ntohl(th->seq); 1588 TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin + 1589 skb->len - th->doff*4); 1590 TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq); 1591 TCP_SKB_CB(skb)->when = 0; 1592 TCP_SKB_CB(skb)->flags = ipv6_get_dsfield(skb->nh.ipv6h); 1593 TCP_SKB_CB(skb)->sacked = 0; 1594 1595 sk = __inet6_lookup(&tcp_hashinfo, &skb->nh.ipv6h->saddr, th->source, 1596 &skb->nh.ipv6h->daddr, ntohs(th->dest), 1597 inet6_iif(skb)); 1598 1599 if (!sk) 1600 goto no_tcp_socket; 1601 1602 process: 1603 if (sk->sk_state == TCP_TIME_WAIT) 1604 goto do_time_wait; 1605 1606 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) 1607 goto discard_and_relse; 1608 1609 if (sk_filter(sk, skb, 0)) 1610 goto discard_and_relse; 1611 1612 skb->dev = NULL; 1613 1614 bh_lock_sock(sk); 1615 ret = 0; 1616 if (!sock_owned_by_user(sk)) { 1617 if (!tcp_prequeue(sk, skb)) 1618 ret = tcp_v6_do_rcv(sk, skb); 1619 } else 1620 sk_add_backlog(sk, skb); 1621 bh_unlock_sock(sk); 1622 1623 sock_put(sk); 1624 return ret ? -1 : 0; 1625 1626 no_tcp_socket: 1627 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 1628 goto discard_it; 1629 1630 if (skb->len < (th->doff<<2) || tcp_checksum_complete(skb)) { 1631 bad_packet: 1632 TCP_INC_STATS_BH(TCP_MIB_INERRS); 1633 } else { 1634 tcp_v6_send_reset(skb); 1635 } 1636 1637 discard_it: 1638 1639 /* 1640 * Discard frame 1641 */ 1642 1643 kfree_skb(skb); 1644 return 0; 1645 1646 discard_and_relse: 1647 sock_put(sk); 1648 goto discard_it; 1649 1650 do_time_wait: 1651 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) { 1652 inet_twsk_put((struct inet_timewait_sock *)sk); 1653 goto discard_it; 1654 } 1655 1656 if (skb->len < (th->doff<<2) || tcp_checksum_complete(skb)) { 1657 TCP_INC_STATS_BH(TCP_MIB_INERRS); 1658 inet_twsk_put((struct inet_timewait_sock *)sk); 1659 goto discard_it; 1660 } 1661 1662 switch (tcp_timewait_state_process((struct inet_timewait_sock *)sk, 1663 skb, th)) { 1664 case TCP_TW_SYN: 1665 { 1666 struct sock *sk2; 1667 1668 sk2 = inet6_lookup_listener(&tcp_hashinfo, 1669 &skb->nh.ipv6h->daddr, 1670 ntohs(th->dest), inet6_iif(skb)); 1671 if (sk2 != NULL) { 1672 struct inet_timewait_sock *tw = inet_twsk(sk); 1673 inet_twsk_deschedule(tw, &tcp_death_row); 1674 inet_twsk_put(tw); 1675 sk = sk2; 1676 goto process; 1677 } 1678 /* Fall through to ACK */ 1679 } 1680 case TCP_TW_ACK: 1681 tcp_v6_timewait_ack(sk, skb); 1682 break; 1683 case TCP_TW_RST: 1684 goto no_tcp_socket; 1685 case TCP_TW_SUCCESS:; 1686 } 1687 goto discard_it; 1688 } 1689 1690 static int tcp_v6_rebuild_header(struct sock *sk) 1691 { 1692 int err; 1693 struct dst_entry *dst; 1694 struct ipv6_pinfo *np = inet6_sk(sk); 1695 1696 dst = __sk_dst_check(sk, np->dst_cookie); 1697 1698 if (dst == NULL) { 1699 struct inet_sock *inet = inet_sk(sk); 1700 struct in6_addr *final_p = NULL, final; 1701 struct flowi fl; 1702 1703 memset(&fl, 0, sizeof(fl)); 1704 fl.proto = IPPROTO_TCP; 1705 ipv6_addr_copy(&fl.fl6_dst, &np->daddr); 1706 ipv6_addr_copy(&fl.fl6_src, &np->saddr); 1707 fl.fl6_flowlabel = np->flow_label; 1708 fl.oif = sk->sk_bound_dev_if; 1709 fl.fl_ip_dport = inet->dport; 1710 fl.fl_ip_sport = inet->sport; 1711 1712 if (np->opt && np->opt->srcrt) { 1713 struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt; 1714 ipv6_addr_copy(&final, &fl.fl6_dst); 1715 ipv6_addr_copy(&fl.fl6_dst, rt0->addr); 1716 final_p = &final; 1717 } 1718 1719 err = ip6_dst_lookup(sk, &dst, &fl); 1720 if (err) { 1721 sk->sk_route_caps = 0; 1722 return err; 1723 } 1724 if (final_p) 1725 ipv6_addr_copy(&fl.fl6_dst, final_p); 1726 1727 if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) { 1728 sk->sk_err_soft = -err; 1729 return err; 1730 } 1731 1732 ip6_dst_store(sk, dst, NULL); 1733 sk->sk_route_caps = dst->dev->features & 1734 ~(NETIF_F_IP_CSUM | NETIF_F_TSO); 1735 } 1736 1737 return 0; 1738 } 1739 1740 static int tcp_v6_xmit(struct sk_buff *skb, int ipfragok) 1741 { 1742 struct sock *sk = skb->sk; 1743 struct inet_sock *inet = inet_sk(sk); 1744 struct ipv6_pinfo *np = inet6_sk(sk); 1745 struct flowi fl; 1746 struct dst_entry *dst; 1747 struct in6_addr *final_p = NULL, final; 1748 1749 memset(&fl, 0, sizeof(fl)); 1750 fl.proto = IPPROTO_TCP; 1751 ipv6_addr_copy(&fl.fl6_dst, &np->daddr); 1752 ipv6_addr_copy(&fl.fl6_src, &np->saddr); 1753 fl.fl6_flowlabel = np->flow_label; 1754 IP6_ECN_flow_xmit(sk, fl.fl6_flowlabel); 1755 fl.oif = sk->sk_bound_dev_if; 1756 fl.fl_ip_sport = inet->sport; 1757 fl.fl_ip_dport = inet->dport; 1758 1759 if (np->opt && np->opt->srcrt) { 1760 struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt; 1761 ipv6_addr_copy(&final, &fl.fl6_dst); 1762 ipv6_addr_copy(&fl.fl6_dst, rt0->addr); 1763 final_p = &final; 1764 } 1765 1766 dst = __sk_dst_check(sk, np->dst_cookie); 1767 1768 if (dst == NULL) { 1769 int err = ip6_dst_lookup(sk, &dst, &fl); 1770 1771 if (err) { 1772 sk->sk_err_soft = -err; 1773 return err; 1774 } 1775 1776 if (final_p) 1777 ipv6_addr_copy(&fl.fl6_dst, final_p); 1778 1779 if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) { 1780 sk->sk_route_caps = 0; 1781 return err; 1782 } 1783 1784 ip6_dst_store(sk, dst, NULL); 1785 sk->sk_route_caps = dst->dev->features & 1786 ~(NETIF_F_IP_CSUM | NETIF_F_TSO); 1787 } 1788 1789 skb->dst = dst_clone(dst); 1790 1791 /* Restore final destination back after routing done */ 1792 ipv6_addr_copy(&fl.fl6_dst, &np->daddr); 1793 1794 return ip6_xmit(sk, skb, &fl, np->opt, 0); 1795 } 1796 1797 static void v6_addr2sockaddr(struct sock *sk, struct sockaddr * uaddr) 1798 { 1799 struct ipv6_pinfo *np = inet6_sk(sk); 1800 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) uaddr; 1801 1802 sin6->sin6_family = AF_INET6; 1803 ipv6_addr_copy(&sin6->sin6_addr, &np->daddr); 1804 sin6->sin6_port = inet_sk(sk)->dport; 1805 /* We do not store received flowlabel for TCP */ 1806 sin6->sin6_flowinfo = 0; 1807 sin6->sin6_scope_id = 0; 1808 if (sk->sk_bound_dev_if && 1809 ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) 1810 sin6->sin6_scope_id = sk->sk_bound_dev_if; 1811 } 1812 1813 static int tcp_v6_remember_stamp(struct sock *sk) 1814 { 1815 /* Alas, not yet... */ 1816 return 0; 1817 } 1818 1819 static struct tcp_func ipv6_specific = { 1820 .queue_xmit = tcp_v6_xmit, 1821 .send_check = tcp_v6_send_check, 1822 .rebuild_header = tcp_v6_rebuild_header, 1823 .conn_request = tcp_v6_conn_request, 1824 .syn_recv_sock = tcp_v6_syn_recv_sock, 1825 .remember_stamp = tcp_v6_remember_stamp, 1826 .net_header_len = sizeof(struct ipv6hdr), 1827 1828 .setsockopt = ipv6_setsockopt, 1829 .getsockopt = ipv6_getsockopt, 1830 .addr2sockaddr = v6_addr2sockaddr, 1831 .sockaddr_len = sizeof(struct sockaddr_in6) 1832 }; 1833 1834 /* 1835 * TCP over IPv4 via INET6 API 1836 */ 1837 1838 static struct tcp_func ipv6_mapped = { 1839 .queue_xmit = ip_queue_xmit, 1840 .send_check = tcp_v4_send_check, 1841 .rebuild_header = inet_sk_rebuild_header, 1842 .conn_request = tcp_v6_conn_request, 1843 .syn_recv_sock = tcp_v6_syn_recv_sock, 1844 .remember_stamp = tcp_v4_remember_stamp, 1845 .net_header_len = sizeof(struct iphdr), 1846 1847 .setsockopt = ipv6_setsockopt, 1848 .getsockopt = ipv6_getsockopt, 1849 .addr2sockaddr = v6_addr2sockaddr, 1850 .sockaddr_len = sizeof(struct sockaddr_in6) 1851 }; 1852 1853 1854 1855 /* NOTE: A lot of things set to zero explicitly by call to 1856 * sk_alloc() so need not be done here. 1857 */ 1858 static int tcp_v6_init_sock(struct sock *sk) 1859 { 1860 struct inet_connection_sock *icsk = inet_csk(sk); 1861 struct tcp_sock *tp = tcp_sk(sk); 1862 1863 skb_queue_head_init(&tp->out_of_order_queue); 1864 tcp_init_xmit_timers(sk); 1865 tcp_prequeue_init(tp); 1866 1867 icsk->icsk_rto = TCP_TIMEOUT_INIT; 1868 tp->mdev = TCP_TIMEOUT_INIT; 1869 1870 /* So many TCP implementations out there (incorrectly) count the 1871 * initial SYN frame in their delayed-ACK and congestion control 1872 * algorithms that we must have the following bandaid to talk 1873 * efficiently to them. -DaveM 1874 */ 1875 tp->snd_cwnd = 2; 1876 1877 /* See draft-stevens-tcpca-spec-01 for discussion of the 1878 * initialization of these values. 1879 */ 1880 tp->snd_ssthresh = 0x7fffffff; 1881 tp->snd_cwnd_clamp = ~0; 1882 tp->mss_cache = 536; 1883 1884 tp->reordering = sysctl_tcp_reordering; 1885 1886 sk->sk_state = TCP_CLOSE; 1887 1888 tp->af_specific = &ipv6_specific; 1889 icsk->icsk_ca_ops = &tcp_init_congestion_ops; 1890 sk->sk_write_space = sk_stream_write_space; 1891 sock_set_flag(sk, SOCK_USE_WRITE_QUEUE); 1892 1893 sk->sk_sndbuf = sysctl_tcp_wmem[1]; 1894 sk->sk_rcvbuf = sysctl_tcp_rmem[1]; 1895 1896 atomic_inc(&tcp_sockets_allocated); 1897 1898 return 0; 1899 } 1900 1901 static int tcp_v6_destroy_sock(struct sock *sk) 1902 { 1903 tcp_v4_destroy_sock(sk); 1904 return inet6_destroy_sock(sk); 1905 } 1906 1907 /* Proc filesystem TCPv6 sock list dumping. */ 1908 static void get_openreq6(struct seq_file *seq, 1909 struct sock *sk, struct request_sock *req, int i, int uid) 1910 { 1911 struct in6_addr *dest, *src; 1912 int ttd = req->expires - jiffies; 1913 1914 if (ttd < 0) 1915 ttd = 0; 1916 1917 src = &tcp6_rsk(req)->loc_addr; 1918 dest = &tcp6_rsk(req)->rmt_addr; 1919 seq_printf(seq, 1920 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1921 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %p\n", 1922 i, 1923 src->s6_addr32[0], src->s6_addr32[1], 1924 src->s6_addr32[2], src->s6_addr32[3], 1925 ntohs(inet_sk(sk)->sport), 1926 dest->s6_addr32[0], dest->s6_addr32[1], 1927 dest->s6_addr32[2], dest->s6_addr32[3], 1928 ntohs(inet_rsk(req)->rmt_port), 1929 TCP_SYN_RECV, 1930 0,0, /* could print option size, but that is af dependent. */ 1931 1, /* timers active (only the expire timer) */ 1932 jiffies_to_clock_t(ttd), 1933 req->retrans, 1934 uid, 1935 0, /* non standard timer */ 1936 0, /* open_requests have no inode */ 1937 0, req); 1938 } 1939 1940 static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i) 1941 { 1942 struct in6_addr *dest, *src; 1943 __u16 destp, srcp; 1944 int timer_active; 1945 unsigned long timer_expires; 1946 struct inet_sock *inet = inet_sk(sp); 1947 struct tcp_sock *tp = tcp_sk(sp); 1948 const struct inet_connection_sock *icsk = inet_csk(sp); 1949 struct ipv6_pinfo *np = inet6_sk(sp); 1950 1951 dest = &np->daddr; 1952 src = &np->rcv_saddr; 1953 destp = ntohs(inet->dport); 1954 srcp = ntohs(inet->sport); 1955 1956 if (icsk->icsk_pending == ICSK_TIME_RETRANS) { 1957 timer_active = 1; 1958 timer_expires = icsk->icsk_timeout; 1959 } else if (icsk->icsk_pending == ICSK_TIME_PROBE0) { 1960 timer_active = 4; 1961 timer_expires = icsk->icsk_timeout; 1962 } else if (timer_pending(&sp->sk_timer)) { 1963 timer_active = 2; 1964 timer_expires = sp->sk_timer.expires; 1965 } else { 1966 timer_active = 0; 1967 timer_expires = jiffies; 1968 } 1969 1970 seq_printf(seq, 1971 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1972 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %p %u %u %u %u %d\n", 1973 i, 1974 src->s6_addr32[0], src->s6_addr32[1], 1975 src->s6_addr32[2], src->s6_addr32[3], srcp, 1976 dest->s6_addr32[0], dest->s6_addr32[1], 1977 dest->s6_addr32[2], dest->s6_addr32[3], destp, 1978 sp->sk_state, 1979 tp->write_seq-tp->snd_una, tp->rcv_nxt-tp->copied_seq, 1980 timer_active, 1981 jiffies_to_clock_t(timer_expires - jiffies), 1982 icsk->icsk_retransmits, 1983 sock_i_uid(sp), 1984 icsk->icsk_probes_out, 1985 sock_i_ino(sp), 1986 atomic_read(&sp->sk_refcnt), sp, 1987 icsk->icsk_rto, 1988 icsk->icsk_ack.ato, 1989 (icsk->icsk_ack.quick << 1 ) | icsk->icsk_ack.pingpong, 1990 tp->snd_cwnd, tp->snd_ssthresh>=0xFFFF?-1:tp->snd_ssthresh 1991 ); 1992 } 1993 1994 static void get_timewait6_sock(struct seq_file *seq, 1995 struct inet_timewait_sock *tw, int i) 1996 { 1997 struct in6_addr *dest, *src; 1998 __u16 destp, srcp; 1999 struct tcp6_timewait_sock *tcp6tw = tcp6_twsk((struct sock *)tw); 2000 int ttd = tw->tw_ttd - jiffies; 2001 2002 if (ttd < 0) 2003 ttd = 0; 2004 2005 dest = &tcp6tw->tw_v6_daddr; 2006 src = &tcp6tw->tw_v6_rcv_saddr; 2007 destp = ntohs(tw->tw_dport); 2008 srcp = ntohs(tw->tw_sport); 2009 2010 seq_printf(seq, 2011 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 2012 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %p\n", 2013 i, 2014 src->s6_addr32[0], src->s6_addr32[1], 2015 src->s6_addr32[2], src->s6_addr32[3], srcp, 2016 dest->s6_addr32[0], dest->s6_addr32[1], 2017 dest->s6_addr32[2], dest->s6_addr32[3], destp, 2018 tw->tw_substate, 0, 0, 2019 3, jiffies_to_clock_t(ttd), 0, 0, 0, 0, 2020 atomic_read(&tw->tw_refcnt), tw); 2021 } 2022 2023 #ifdef CONFIG_PROC_FS 2024 static int tcp6_seq_show(struct seq_file *seq, void *v) 2025 { 2026 struct tcp_iter_state *st; 2027 2028 if (v == SEQ_START_TOKEN) { 2029 seq_puts(seq, 2030 " sl " 2031 "local_address " 2032 "remote_address " 2033 "st tx_queue rx_queue tr tm->when retrnsmt" 2034 " uid timeout inode\n"); 2035 goto out; 2036 } 2037 st = seq->private; 2038 2039 switch (st->state) { 2040 case TCP_SEQ_STATE_LISTENING: 2041 case TCP_SEQ_STATE_ESTABLISHED: 2042 get_tcp6_sock(seq, v, st->num); 2043 break; 2044 case TCP_SEQ_STATE_OPENREQ: 2045 get_openreq6(seq, st->syn_wait_sk, v, st->num, st->uid); 2046 break; 2047 case TCP_SEQ_STATE_TIME_WAIT: 2048 get_timewait6_sock(seq, v, st->num); 2049 break; 2050 } 2051 out: 2052 return 0; 2053 } 2054 2055 static struct file_operations tcp6_seq_fops; 2056 static struct tcp_seq_afinfo tcp6_seq_afinfo = { 2057 .owner = THIS_MODULE, 2058 .name = "tcp6", 2059 .family = AF_INET6, 2060 .seq_show = tcp6_seq_show, 2061 .seq_fops = &tcp6_seq_fops, 2062 }; 2063 2064 int __init tcp6_proc_init(void) 2065 { 2066 return tcp_proc_register(&tcp6_seq_afinfo); 2067 } 2068 2069 void tcp6_proc_exit(void) 2070 { 2071 tcp_proc_unregister(&tcp6_seq_afinfo); 2072 } 2073 #endif 2074 2075 struct proto tcpv6_prot = { 2076 .name = "TCPv6", 2077 .owner = THIS_MODULE, 2078 .close = tcp_close, 2079 .connect = tcp_v6_connect, 2080 .disconnect = tcp_disconnect, 2081 .accept = inet_csk_accept, 2082 .ioctl = tcp_ioctl, 2083 .init = tcp_v6_init_sock, 2084 .destroy = tcp_v6_destroy_sock, 2085 .shutdown = tcp_shutdown, 2086 .setsockopt = tcp_setsockopt, 2087 .getsockopt = tcp_getsockopt, 2088 .sendmsg = tcp_sendmsg, 2089 .recvmsg = tcp_recvmsg, 2090 .backlog_rcv = tcp_v6_do_rcv, 2091 .hash = tcp_v6_hash, 2092 .unhash = tcp_unhash, 2093 .get_port = tcp_v6_get_port, 2094 .enter_memory_pressure = tcp_enter_memory_pressure, 2095 .sockets_allocated = &tcp_sockets_allocated, 2096 .memory_allocated = &tcp_memory_allocated, 2097 .memory_pressure = &tcp_memory_pressure, 2098 .orphan_count = &tcp_orphan_count, 2099 .sysctl_mem = sysctl_tcp_mem, 2100 .sysctl_wmem = sysctl_tcp_wmem, 2101 .sysctl_rmem = sysctl_tcp_rmem, 2102 .max_header = MAX_TCP_HEADER, 2103 .obj_size = sizeof(struct tcp6_sock), 2104 .twsk_obj_size = sizeof(struct tcp6_timewait_sock), 2105 .rsk_prot = &tcp6_request_sock_ops, 2106 }; 2107 2108 static struct inet6_protocol tcpv6_protocol = { 2109 .handler = tcp_v6_rcv, 2110 .err_handler = tcp_v6_err, 2111 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 2112 }; 2113 2114 static struct inet_protosw tcpv6_protosw = { 2115 .type = SOCK_STREAM, 2116 .protocol = IPPROTO_TCP, 2117 .prot = &tcpv6_prot, 2118 .ops = &inet6_stream_ops, 2119 .capability = -1, 2120 .no_check = 0, 2121 .flags = INET_PROTOSW_PERMANENT, 2122 }; 2123 2124 void __init tcpv6_init(void) 2125 { 2126 /* register inet6 protocol */ 2127 if (inet6_add_protocol(&tcpv6_protocol, IPPROTO_TCP) < 0) 2128 printk(KERN_ERR "tcpv6_init: Could not register protocol\n"); 2129 inet6_register_protosw(&tcpv6_protosw); 2130 } 2131