1 /* 2 * TCP over IPv6 3 * Linux INET6 implementation 4 * 5 * Authors: 6 * Pedro Roque <roque@di.fc.ul.pt> 7 * 8 * Based on: 9 * linux/net/ipv4/tcp.c 10 * linux/net/ipv4/tcp_input.c 11 * linux/net/ipv4/tcp_output.c 12 * 13 * Fixes: 14 * Hideaki YOSHIFUJI : sin6_scope_id support 15 * YOSHIFUJI Hideaki @USAGI and: Support IPV6_V6ONLY socket option, which 16 * Alexey Kuznetsov allow both IPv4 and IPv6 sockets to bind 17 * a single port at the same time. 18 * YOSHIFUJI Hideaki @USAGI: convert /proc/net/tcp6 to seq_file. 19 * 20 * This program is free software; you can redistribute it and/or 21 * modify it under the terms of the GNU General Public License 22 * as published by the Free Software Foundation; either version 23 * 2 of the License, or (at your option) any later version. 24 */ 25 26 #include <linux/bottom_half.h> 27 #include <linux/module.h> 28 #include <linux/errno.h> 29 #include <linux/types.h> 30 #include <linux/socket.h> 31 #include <linux/sockios.h> 32 #include <linux/net.h> 33 #include <linux/jiffies.h> 34 #include <linux/in.h> 35 #include <linux/in6.h> 36 #include <linux/netdevice.h> 37 #include <linux/init.h> 38 #include <linux/jhash.h> 39 #include <linux/ipsec.h> 40 #include <linux/times.h> 41 #include <linux/slab.h> 42 #include <linux/uaccess.h> 43 #include <linux/ipv6.h> 44 #include <linux/icmpv6.h> 45 #include <linux/random.h> 46 47 #include <net/tcp.h> 48 #include <net/ndisc.h> 49 #include <net/inet6_hashtables.h> 50 #include <net/inet6_connection_sock.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/snmp.h> 60 #include <net/dsfield.h> 61 #include <net/timewait_sock.h> 62 #include <net/inet_common.h> 63 #include <net/secure_seq.h> 64 #include <net/busy_poll.h> 65 66 #include <linux/proc_fs.h> 67 #include <linux/seq_file.h> 68 69 #include <crypto/hash.h> 70 #include <linux/scatterlist.h> 71 72 static void tcp_v6_send_reset(const struct sock *sk, struct sk_buff *skb); 73 static void tcp_v6_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, 74 struct request_sock *req); 75 76 static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb); 77 78 static const struct inet_connection_sock_af_ops ipv6_mapped; 79 static const struct inet_connection_sock_af_ops ipv6_specific; 80 #ifdef CONFIG_TCP_MD5SIG 81 static const struct tcp_sock_af_ops tcp_sock_ipv6_specific; 82 static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific; 83 #else 84 static struct tcp_md5sig_key *tcp_v6_md5_do_lookup(const struct sock *sk, 85 const struct in6_addr *addr) 86 { 87 return NULL; 88 } 89 #endif 90 91 static void inet6_sk_rx_dst_set(struct sock *sk, const struct sk_buff *skb) 92 { 93 struct dst_entry *dst = skb_dst(skb); 94 95 if (dst && dst_hold_safe(dst)) { 96 const struct rt6_info *rt = (const struct rt6_info *)dst; 97 98 sk->sk_rx_dst = dst; 99 inet_sk(sk)->rx_dst_ifindex = skb->skb_iif; 100 inet6_sk(sk)->rx_dst_cookie = rt6_get_cookie(rt); 101 } 102 } 103 104 static __u32 tcp_v6_init_sequence(const struct sk_buff *skb) 105 { 106 return secure_tcpv6_sequence_number(ipv6_hdr(skb)->daddr.s6_addr32, 107 ipv6_hdr(skb)->saddr.s6_addr32, 108 tcp_hdr(skb)->dest, 109 tcp_hdr(skb)->source); 110 } 111 112 static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr, 113 int addr_len) 114 { 115 struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr; 116 struct inet_sock *inet = inet_sk(sk); 117 struct inet_connection_sock *icsk = inet_csk(sk); 118 struct ipv6_pinfo *np = inet6_sk(sk); 119 struct tcp_sock *tp = tcp_sk(sk); 120 struct in6_addr *saddr = NULL, *final_p, final; 121 struct ipv6_txoptions *opt; 122 struct flowi6 fl6; 123 struct dst_entry *dst; 124 int addr_type; 125 int err; 126 127 if (addr_len < SIN6_LEN_RFC2133) 128 return -EINVAL; 129 130 if (usin->sin6_family != AF_INET6) 131 return -EAFNOSUPPORT; 132 133 memset(&fl6, 0, sizeof(fl6)); 134 135 if (np->sndflow) { 136 fl6.flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK; 137 IP6_ECN_flow_init(fl6.flowlabel); 138 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) { 139 struct ip6_flowlabel *flowlabel; 140 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel); 141 if (!flowlabel) 142 return -EINVAL; 143 fl6_sock_release(flowlabel); 144 } 145 } 146 147 /* 148 * connect() to INADDR_ANY means loopback (BSD'ism). 149 */ 150 151 if (ipv6_addr_any(&usin->sin6_addr)) 152 usin->sin6_addr.s6_addr[15] = 0x1; 153 154 addr_type = ipv6_addr_type(&usin->sin6_addr); 155 156 if (addr_type & IPV6_ADDR_MULTICAST) 157 return -ENETUNREACH; 158 159 if (addr_type&IPV6_ADDR_LINKLOCAL) { 160 if (addr_len >= sizeof(struct sockaddr_in6) && 161 usin->sin6_scope_id) { 162 /* If interface is set while binding, indices 163 * must coincide. 164 */ 165 if (sk->sk_bound_dev_if && 166 sk->sk_bound_dev_if != usin->sin6_scope_id) 167 return -EINVAL; 168 169 sk->sk_bound_dev_if = usin->sin6_scope_id; 170 } 171 172 /* Connect to link-local address requires an interface */ 173 if (!sk->sk_bound_dev_if) 174 return -EINVAL; 175 } 176 177 if (tp->rx_opt.ts_recent_stamp && 178 !ipv6_addr_equal(&sk->sk_v6_daddr, &usin->sin6_addr)) { 179 tp->rx_opt.ts_recent = 0; 180 tp->rx_opt.ts_recent_stamp = 0; 181 tp->write_seq = 0; 182 } 183 184 sk->sk_v6_daddr = usin->sin6_addr; 185 np->flow_label = fl6.flowlabel; 186 187 /* 188 * TCP over IPv4 189 */ 190 191 if (addr_type == IPV6_ADDR_MAPPED) { 192 u32 exthdrlen = icsk->icsk_ext_hdr_len; 193 struct sockaddr_in sin; 194 195 SOCK_DEBUG(sk, "connect: ipv4 mapped\n"); 196 197 if (__ipv6_only_sock(sk)) 198 return -ENETUNREACH; 199 200 sin.sin_family = AF_INET; 201 sin.sin_port = usin->sin6_port; 202 sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3]; 203 204 icsk->icsk_af_ops = &ipv6_mapped; 205 sk->sk_backlog_rcv = tcp_v4_do_rcv; 206 #ifdef CONFIG_TCP_MD5SIG 207 tp->af_specific = &tcp_sock_ipv6_mapped_specific; 208 #endif 209 210 err = tcp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin)); 211 212 if (err) { 213 icsk->icsk_ext_hdr_len = exthdrlen; 214 icsk->icsk_af_ops = &ipv6_specific; 215 sk->sk_backlog_rcv = tcp_v6_do_rcv; 216 #ifdef CONFIG_TCP_MD5SIG 217 tp->af_specific = &tcp_sock_ipv6_specific; 218 #endif 219 goto failure; 220 } 221 np->saddr = sk->sk_v6_rcv_saddr; 222 223 return err; 224 } 225 226 if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) 227 saddr = &sk->sk_v6_rcv_saddr; 228 229 fl6.flowi6_proto = IPPROTO_TCP; 230 fl6.daddr = sk->sk_v6_daddr; 231 fl6.saddr = saddr ? *saddr : np->saddr; 232 fl6.flowi6_oif = sk->sk_bound_dev_if; 233 fl6.flowi6_mark = sk->sk_mark; 234 fl6.fl6_dport = usin->sin6_port; 235 fl6.fl6_sport = inet->inet_sport; 236 237 opt = rcu_dereference_protected(np->opt, sock_owned_by_user(sk)); 238 final_p = fl6_update_dst(&fl6, opt, &final); 239 240 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6)); 241 242 dst = ip6_dst_lookup_flow(sk, &fl6, final_p); 243 if (IS_ERR(dst)) { 244 err = PTR_ERR(dst); 245 goto failure; 246 } 247 248 if (!saddr) { 249 saddr = &fl6.saddr; 250 sk->sk_v6_rcv_saddr = *saddr; 251 } 252 253 /* set the source address */ 254 np->saddr = *saddr; 255 inet->inet_rcv_saddr = LOOPBACK4_IPV6; 256 257 sk->sk_gso_type = SKB_GSO_TCPV6; 258 ip6_dst_store(sk, dst, NULL, NULL); 259 260 if (tcp_death_row.sysctl_tw_recycle && 261 !tp->rx_opt.ts_recent_stamp && 262 ipv6_addr_equal(&fl6.daddr, &sk->sk_v6_daddr)) 263 tcp_fetch_timewait_stamp(sk, dst); 264 265 icsk->icsk_ext_hdr_len = 0; 266 if (opt) 267 icsk->icsk_ext_hdr_len = opt->opt_flen + 268 opt->opt_nflen; 269 270 tp->rx_opt.mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - sizeof(struct ipv6hdr); 271 272 inet->inet_dport = usin->sin6_port; 273 274 tcp_set_state(sk, TCP_SYN_SENT); 275 err = inet6_hash_connect(&tcp_death_row, sk); 276 if (err) 277 goto late_failure; 278 279 sk_set_txhash(sk); 280 281 if (!tp->write_seq && likely(!tp->repair)) 282 tp->write_seq = secure_tcpv6_sequence_number(np->saddr.s6_addr32, 283 sk->sk_v6_daddr.s6_addr32, 284 inet->inet_sport, 285 inet->inet_dport); 286 287 err = tcp_connect(sk); 288 if (err) 289 goto late_failure; 290 291 return 0; 292 293 late_failure: 294 tcp_set_state(sk, TCP_CLOSE); 295 __sk_dst_reset(sk); 296 failure: 297 inet->inet_dport = 0; 298 sk->sk_route_caps = 0; 299 return err; 300 } 301 302 static void tcp_v6_mtu_reduced(struct sock *sk) 303 { 304 struct dst_entry *dst; 305 306 if ((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) 307 return; 308 309 dst = inet6_csk_update_pmtu(sk, tcp_sk(sk)->mtu_info); 310 if (!dst) 311 return; 312 313 if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst)) { 314 tcp_sync_mss(sk, dst_mtu(dst)); 315 tcp_simple_retransmit(sk); 316 } 317 } 318 319 static void tcp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 320 u8 type, u8 code, int offset, __be32 info) 321 { 322 const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data; 323 const struct tcphdr *th = (struct tcphdr *)(skb->data+offset); 324 struct net *net = dev_net(skb->dev); 325 struct request_sock *fastopen; 326 struct ipv6_pinfo *np; 327 struct tcp_sock *tp; 328 __u32 seq, snd_una; 329 struct sock *sk; 330 bool fatal; 331 int err; 332 333 sk = __inet6_lookup_established(net, &tcp_hashinfo, 334 &hdr->daddr, th->dest, 335 &hdr->saddr, ntohs(th->source), 336 skb->dev->ifindex); 337 338 if (!sk) { 339 ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev), 340 ICMP6_MIB_INERRORS); 341 return; 342 } 343 344 if (sk->sk_state == TCP_TIME_WAIT) { 345 inet_twsk_put(inet_twsk(sk)); 346 return; 347 } 348 seq = ntohl(th->seq); 349 fatal = icmpv6_err_convert(type, code, &err); 350 if (sk->sk_state == TCP_NEW_SYN_RECV) 351 return tcp_req_err(sk, seq, fatal); 352 353 bh_lock_sock(sk); 354 if (sock_owned_by_user(sk) && type != ICMPV6_PKT_TOOBIG) 355 NET_INC_STATS_BH(net, LINUX_MIB_LOCKDROPPEDICMPS); 356 357 if (sk->sk_state == TCP_CLOSE) 358 goto out; 359 360 if (ipv6_hdr(skb)->hop_limit < inet6_sk(sk)->min_hopcount) { 361 NET_INC_STATS_BH(net, LINUX_MIB_TCPMINTTLDROP); 362 goto out; 363 } 364 365 tp = tcp_sk(sk); 366 /* XXX (TFO) - tp->snd_una should be ISN (tcp_create_openreq_child() */ 367 fastopen = tp->fastopen_rsk; 368 snd_una = fastopen ? tcp_rsk(fastopen)->snt_isn : tp->snd_una; 369 if (sk->sk_state != TCP_LISTEN && 370 !between(seq, snd_una, tp->snd_nxt)) { 371 NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS); 372 goto out; 373 } 374 375 np = inet6_sk(sk); 376 377 if (type == NDISC_REDIRECT) { 378 struct dst_entry *dst = __sk_dst_check(sk, np->dst_cookie); 379 380 if (dst) 381 dst->ops->redirect(dst, sk, skb); 382 goto out; 383 } 384 385 if (type == ICMPV6_PKT_TOOBIG) { 386 /* We are not interested in TCP_LISTEN and open_requests 387 * (SYN-ACKs send out by Linux are always <576bytes so 388 * they should go through unfragmented). 389 */ 390 if (sk->sk_state == TCP_LISTEN) 391 goto out; 392 393 if (!ip6_sk_accept_pmtu(sk)) 394 goto out; 395 396 tp->mtu_info = ntohl(info); 397 if (!sock_owned_by_user(sk)) 398 tcp_v6_mtu_reduced(sk); 399 else if (!test_and_set_bit(TCP_MTU_REDUCED_DEFERRED, 400 &tp->tsq_flags)) 401 sock_hold(sk); 402 goto out; 403 } 404 405 406 /* Might be for an request_sock */ 407 switch (sk->sk_state) { 408 case TCP_SYN_SENT: 409 case TCP_SYN_RECV: 410 /* Only in fast or simultaneous open. If a fast open socket is 411 * is already accepted it is treated as a connected one below. 412 */ 413 if (fastopen && !fastopen->sk) 414 break; 415 416 if (!sock_owned_by_user(sk)) { 417 sk->sk_err = err; 418 sk->sk_error_report(sk); /* Wake people up to see the error (see connect in sock.c) */ 419 420 tcp_done(sk); 421 } else 422 sk->sk_err_soft = err; 423 goto out; 424 } 425 426 if (!sock_owned_by_user(sk) && np->recverr) { 427 sk->sk_err = err; 428 sk->sk_error_report(sk); 429 } else 430 sk->sk_err_soft = err; 431 432 out: 433 bh_unlock_sock(sk); 434 sock_put(sk); 435 } 436 437 438 static int tcp_v6_send_synack(const struct sock *sk, struct dst_entry *dst, 439 struct flowi *fl, 440 struct request_sock *req, 441 struct tcp_fastopen_cookie *foc, 442 bool attach_req) 443 { 444 struct inet_request_sock *ireq = inet_rsk(req); 445 struct ipv6_pinfo *np = inet6_sk(sk); 446 struct flowi6 *fl6 = &fl->u.ip6; 447 struct sk_buff *skb; 448 int err = -ENOMEM; 449 450 /* First, grab a route. */ 451 if (!dst && (dst = inet6_csk_route_req(sk, fl6, req, 452 IPPROTO_TCP)) == NULL) 453 goto done; 454 455 skb = tcp_make_synack(sk, dst, req, foc, attach_req); 456 457 if (skb) { 458 __tcp_v6_send_check(skb, &ireq->ir_v6_loc_addr, 459 &ireq->ir_v6_rmt_addr); 460 461 fl6->daddr = ireq->ir_v6_rmt_addr; 462 if (np->repflow && ireq->pktopts) 463 fl6->flowlabel = ip6_flowlabel(ipv6_hdr(ireq->pktopts)); 464 465 rcu_read_lock(); 466 err = ip6_xmit(sk, skb, fl6, rcu_dereference(np->opt), 467 np->tclass); 468 rcu_read_unlock(); 469 err = net_xmit_eval(err); 470 } 471 472 done: 473 return err; 474 } 475 476 477 static void tcp_v6_reqsk_destructor(struct request_sock *req) 478 { 479 kfree_skb(inet_rsk(req)->pktopts); 480 } 481 482 #ifdef CONFIG_TCP_MD5SIG 483 static struct tcp_md5sig_key *tcp_v6_md5_do_lookup(const struct sock *sk, 484 const struct in6_addr *addr) 485 { 486 return tcp_md5_do_lookup(sk, (union tcp_md5_addr *)addr, AF_INET6); 487 } 488 489 static struct tcp_md5sig_key *tcp_v6_md5_lookup(const struct sock *sk, 490 const struct sock *addr_sk) 491 { 492 return tcp_v6_md5_do_lookup(sk, &addr_sk->sk_v6_daddr); 493 } 494 495 static int tcp_v6_parse_md5_keys(struct sock *sk, char __user *optval, 496 int optlen) 497 { 498 struct tcp_md5sig cmd; 499 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&cmd.tcpm_addr; 500 501 if (optlen < sizeof(cmd)) 502 return -EINVAL; 503 504 if (copy_from_user(&cmd, optval, sizeof(cmd))) 505 return -EFAULT; 506 507 if (sin6->sin6_family != AF_INET6) 508 return -EINVAL; 509 510 if (!cmd.tcpm_keylen) { 511 if (ipv6_addr_v4mapped(&sin6->sin6_addr)) 512 return tcp_md5_do_del(sk, (union tcp_md5_addr *)&sin6->sin6_addr.s6_addr32[3], 513 AF_INET); 514 return tcp_md5_do_del(sk, (union tcp_md5_addr *)&sin6->sin6_addr, 515 AF_INET6); 516 } 517 518 if (cmd.tcpm_keylen > TCP_MD5SIG_MAXKEYLEN) 519 return -EINVAL; 520 521 if (ipv6_addr_v4mapped(&sin6->sin6_addr)) 522 return tcp_md5_do_add(sk, (union tcp_md5_addr *)&sin6->sin6_addr.s6_addr32[3], 523 AF_INET, cmd.tcpm_key, cmd.tcpm_keylen, GFP_KERNEL); 524 525 return tcp_md5_do_add(sk, (union tcp_md5_addr *)&sin6->sin6_addr, 526 AF_INET6, cmd.tcpm_key, cmd.tcpm_keylen, GFP_KERNEL); 527 } 528 529 static int tcp_v6_md5_hash_pseudoheader(struct tcp_md5sig_pool *hp, 530 const struct in6_addr *daddr, 531 const struct in6_addr *saddr, int nbytes) 532 { 533 struct tcp6_pseudohdr *bp; 534 struct scatterlist sg; 535 536 bp = &hp->md5_blk.ip6; 537 /* 1. TCP pseudo-header (RFC2460) */ 538 bp->saddr = *saddr; 539 bp->daddr = *daddr; 540 bp->protocol = cpu_to_be32(IPPROTO_TCP); 541 bp->len = cpu_to_be32(nbytes); 542 543 sg_init_one(&sg, bp, sizeof(*bp)); 544 ahash_request_set_crypt(hp->md5_req, &sg, NULL, sizeof(*bp)); 545 return crypto_ahash_update(hp->md5_req); 546 } 547 548 static int tcp_v6_md5_hash_hdr(char *md5_hash, struct tcp_md5sig_key *key, 549 const struct in6_addr *daddr, struct in6_addr *saddr, 550 const struct tcphdr *th) 551 { 552 struct tcp_md5sig_pool *hp; 553 struct ahash_request *req; 554 555 hp = tcp_get_md5sig_pool(); 556 if (!hp) 557 goto clear_hash_noput; 558 req = hp->md5_req; 559 560 if (crypto_ahash_init(req)) 561 goto clear_hash; 562 if (tcp_v6_md5_hash_pseudoheader(hp, daddr, saddr, th->doff << 2)) 563 goto clear_hash; 564 if (tcp_md5_hash_header(hp, th)) 565 goto clear_hash; 566 if (tcp_md5_hash_key(hp, key)) 567 goto clear_hash; 568 ahash_request_set_crypt(req, NULL, md5_hash, 0); 569 if (crypto_ahash_final(req)) 570 goto clear_hash; 571 572 tcp_put_md5sig_pool(); 573 return 0; 574 575 clear_hash: 576 tcp_put_md5sig_pool(); 577 clear_hash_noput: 578 memset(md5_hash, 0, 16); 579 return 1; 580 } 581 582 static int tcp_v6_md5_hash_skb(char *md5_hash, 583 const struct tcp_md5sig_key *key, 584 const struct sock *sk, 585 const struct sk_buff *skb) 586 { 587 const struct in6_addr *saddr, *daddr; 588 struct tcp_md5sig_pool *hp; 589 struct ahash_request *req; 590 const struct tcphdr *th = tcp_hdr(skb); 591 592 if (sk) { /* valid for establish/request sockets */ 593 saddr = &sk->sk_v6_rcv_saddr; 594 daddr = &sk->sk_v6_daddr; 595 } else { 596 const struct ipv6hdr *ip6h = ipv6_hdr(skb); 597 saddr = &ip6h->saddr; 598 daddr = &ip6h->daddr; 599 } 600 601 hp = tcp_get_md5sig_pool(); 602 if (!hp) 603 goto clear_hash_noput; 604 req = hp->md5_req; 605 606 if (crypto_ahash_init(req)) 607 goto clear_hash; 608 609 if (tcp_v6_md5_hash_pseudoheader(hp, daddr, saddr, skb->len)) 610 goto clear_hash; 611 if (tcp_md5_hash_header(hp, th)) 612 goto clear_hash; 613 if (tcp_md5_hash_skb_data(hp, skb, th->doff << 2)) 614 goto clear_hash; 615 if (tcp_md5_hash_key(hp, key)) 616 goto clear_hash; 617 ahash_request_set_crypt(req, NULL, md5_hash, 0); 618 if (crypto_ahash_final(req)) 619 goto clear_hash; 620 621 tcp_put_md5sig_pool(); 622 return 0; 623 624 clear_hash: 625 tcp_put_md5sig_pool(); 626 clear_hash_noput: 627 memset(md5_hash, 0, 16); 628 return 1; 629 } 630 631 #endif 632 633 static bool tcp_v6_inbound_md5_hash(const struct sock *sk, 634 const struct sk_buff *skb) 635 { 636 #ifdef CONFIG_TCP_MD5SIG 637 const __u8 *hash_location = NULL; 638 struct tcp_md5sig_key *hash_expected; 639 const struct ipv6hdr *ip6h = ipv6_hdr(skb); 640 const struct tcphdr *th = tcp_hdr(skb); 641 int genhash; 642 u8 newhash[16]; 643 644 hash_expected = tcp_v6_md5_do_lookup(sk, &ip6h->saddr); 645 hash_location = tcp_parse_md5sig_option(th); 646 647 /* We've parsed the options - do we have a hash? */ 648 if (!hash_expected && !hash_location) 649 return false; 650 651 if (hash_expected && !hash_location) { 652 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND); 653 return true; 654 } 655 656 if (!hash_expected && hash_location) { 657 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED); 658 return true; 659 } 660 661 /* check the signature */ 662 genhash = tcp_v6_md5_hash_skb(newhash, 663 hash_expected, 664 NULL, skb); 665 666 if (genhash || memcmp(hash_location, newhash, 16) != 0) { 667 net_info_ratelimited("MD5 Hash %s for [%pI6c]:%u->[%pI6c]:%u\n", 668 genhash ? "failed" : "mismatch", 669 &ip6h->saddr, ntohs(th->source), 670 &ip6h->daddr, ntohs(th->dest)); 671 return true; 672 } 673 #endif 674 return false; 675 } 676 677 static void tcp_v6_init_req(struct request_sock *req, 678 const struct sock *sk_listener, 679 struct sk_buff *skb) 680 { 681 struct inet_request_sock *ireq = inet_rsk(req); 682 const struct ipv6_pinfo *np = inet6_sk(sk_listener); 683 684 ireq->ir_v6_rmt_addr = ipv6_hdr(skb)->saddr; 685 ireq->ir_v6_loc_addr = ipv6_hdr(skb)->daddr; 686 687 /* So that link locals have meaning */ 688 if (!sk_listener->sk_bound_dev_if && 689 ipv6_addr_type(&ireq->ir_v6_rmt_addr) & IPV6_ADDR_LINKLOCAL) 690 ireq->ir_iif = tcp_v6_iif(skb); 691 692 if (!TCP_SKB_CB(skb)->tcp_tw_isn && 693 (ipv6_opt_accepted(sk_listener, skb, &TCP_SKB_CB(skb)->header.h6) || 694 np->rxopt.bits.rxinfo || 695 np->rxopt.bits.rxoinfo || np->rxopt.bits.rxhlim || 696 np->rxopt.bits.rxohlim || np->repflow)) { 697 atomic_inc(&skb->users); 698 ireq->pktopts = skb; 699 } 700 } 701 702 static struct dst_entry *tcp_v6_route_req(const struct sock *sk, 703 struct flowi *fl, 704 const struct request_sock *req, 705 bool *strict) 706 { 707 if (strict) 708 *strict = true; 709 return inet6_csk_route_req(sk, &fl->u.ip6, req, IPPROTO_TCP); 710 } 711 712 struct request_sock_ops tcp6_request_sock_ops __read_mostly = { 713 .family = AF_INET6, 714 .obj_size = sizeof(struct tcp6_request_sock), 715 .rtx_syn_ack = tcp_rtx_synack, 716 .send_ack = tcp_v6_reqsk_send_ack, 717 .destructor = tcp_v6_reqsk_destructor, 718 .send_reset = tcp_v6_send_reset, 719 .syn_ack_timeout = tcp_syn_ack_timeout, 720 }; 721 722 static const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops = { 723 .mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - 724 sizeof(struct ipv6hdr), 725 #ifdef CONFIG_TCP_MD5SIG 726 .req_md5_lookup = tcp_v6_md5_lookup, 727 .calc_md5_hash = tcp_v6_md5_hash_skb, 728 #endif 729 .init_req = tcp_v6_init_req, 730 #ifdef CONFIG_SYN_COOKIES 731 .cookie_init_seq = cookie_v6_init_sequence, 732 #endif 733 .route_req = tcp_v6_route_req, 734 .init_seq = tcp_v6_init_sequence, 735 .send_synack = tcp_v6_send_synack, 736 }; 737 738 static void tcp_v6_send_response(const struct sock *sk, struct sk_buff *skb, u32 seq, 739 u32 ack, u32 win, u32 tsval, u32 tsecr, 740 int oif, struct tcp_md5sig_key *key, int rst, 741 u8 tclass, u32 label) 742 { 743 const struct tcphdr *th = tcp_hdr(skb); 744 struct tcphdr *t1; 745 struct sk_buff *buff; 746 struct flowi6 fl6; 747 struct net *net = sk ? sock_net(sk) : dev_net(skb_dst(skb)->dev); 748 struct sock *ctl_sk = net->ipv6.tcp_sk; 749 unsigned int tot_len = sizeof(struct tcphdr); 750 struct dst_entry *dst; 751 __be32 *topt; 752 753 if (tsecr) 754 tot_len += TCPOLEN_TSTAMP_ALIGNED; 755 #ifdef CONFIG_TCP_MD5SIG 756 if (key) 757 tot_len += TCPOLEN_MD5SIG_ALIGNED; 758 #endif 759 760 buff = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + tot_len, 761 GFP_ATOMIC); 762 if (!buff) 763 return; 764 765 skb_reserve(buff, MAX_HEADER + sizeof(struct ipv6hdr) + tot_len); 766 767 t1 = (struct tcphdr *) skb_push(buff, tot_len); 768 skb_reset_transport_header(buff); 769 770 /* Swap the send and the receive. */ 771 memset(t1, 0, sizeof(*t1)); 772 t1->dest = th->source; 773 t1->source = th->dest; 774 t1->doff = tot_len / 4; 775 t1->seq = htonl(seq); 776 t1->ack_seq = htonl(ack); 777 t1->ack = !rst || !th->ack; 778 t1->rst = rst; 779 t1->window = htons(win); 780 781 topt = (__be32 *)(t1 + 1); 782 783 if (tsecr) { 784 *topt++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | 785 (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP); 786 *topt++ = htonl(tsval); 787 *topt++ = htonl(tsecr); 788 } 789 790 #ifdef CONFIG_TCP_MD5SIG 791 if (key) { 792 *topt++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | 793 (TCPOPT_MD5SIG << 8) | TCPOLEN_MD5SIG); 794 tcp_v6_md5_hash_hdr((__u8 *)topt, key, 795 &ipv6_hdr(skb)->saddr, 796 &ipv6_hdr(skb)->daddr, t1); 797 } 798 #endif 799 800 memset(&fl6, 0, sizeof(fl6)); 801 fl6.daddr = ipv6_hdr(skb)->saddr; 802 fl6.saddr = ipv6_hdr(skb)->daddr; 803 fl6.flowlabel = label; 804 805 buff->ip_summed = CHECKSUM_PARTIAL; 806 buff->csum = 0; 807 808 __tcp_v6_send_check(buff, &fl6.saddr, &fl6.daddr); 809 810 fl6.flowi6_proto = IPPROTO_TCP; 811 if (rt6_need_strict(&fl6.daddr) && !oif) 812 fl6.flowi6_oif = tcp_v6_iif(skb); 813 else { 814 if (!oif && netif_index_is_l3_master(net, skb->skb_iif)) 815 oif = skb->skb_iif; 816 817 fl6.flowi6_oif = oif; 818 } 819 820 fl6.flowi6_mark = IP6_REPLY_MARK(net, skb->mark); 821 fl6.fl6_dport = t1->dest; 822 fl6.fl6_sport = t1->source; 823 security_skb_classify_flow(skb, flowi6_to_flowi(&fl6)); 824 825 /* Pass a socket to ip6_dst_lookup either it is for RST 826 * Underlying function will use this to retrieve the network 827 * namespace 828 */ 829 dst = ip6_dst_lookup_flow(ctl_sk, &fl6, NULL); 830 if (!IS_ERR(dst)) { 831 skb_dst_set(buff, dst); 832 ip6_xmit(ctl_sk, buff, &fl6, NULL, tclass); 833 TCP_INC_STATS_BH(net, TCP_MIB_OUTSEGS); 834 if (rst) 835 TCP_INC_STATS_BH(net, TCP_MIB_OUTRSTS); 836 return; 837 } 838 839 kfree_skb(buff); 840 } 841 842 static void tcp_v6_send_reset(const struct sock *sk, struct sk_buff *skb) 843 { 844 const struct tcphdr *th = tcp_hdr(skb); 845 u32 seq = 0, ack_seq = 0; 846 struct tcp_md5sig_key *key = NULL; 847 #ifdef CONFIG_TCP_MD5SIG 848 const __u8 *hash_location = NULL; 849 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 850 unsigned char newhash[16]; 851 int genhash; 852 struct sock *sk1 = NULL; 853 #endif 854 int oif; 855 856 if (th->rst) 857 return; 858 859 /* If sk not NULL, it means we did a successful lookup and incoming 860 * route had to be correct. prequeue might have dropped our dst. 861 */ 862 if (!sk && !ipv6_unicast_destination(skb)) 863 return; 864 865 #ifdef CONFIG_TCP_MD5SIG 866 hash_location = tcp_parse_md5sig_option(th); 867 if (sk && sk_fullsock(sk)) { 868 key = tcp_v6_md5_do_lookup(sk, &ipv6h->saddr); 869 } else if (hash_location) { 870 /* 871 * active side is lost. Try to find listening socket through 872 * source port, and then find md5 key through listening socket. 873 * we are not loose security here: 874 * Incoming packet is checked with md5 hash with finding key, 875 * no RST generated if md5 hash doesn't match. 876 */ 877 sk1 = inet6_lookup_listener(dev_net(skb_dst(skb)->dev), 878 &tcp_hashinfo, NULL, 0, 879 &ipv6h->saddr, 880 th->source, &ipv6h->daddr, 881 ntohs(th->source), tcp_v6_iif(skb)); 882 if (!sk1) 883 return; 884 885 rcu_read_lock(); 886 key = tcp_v6_md5_do_lookup(sk1, &ipv6h->saddr); 887 if (!key) 888 goto release_sk1; 889 890 genhash = tcp_v6_md5_hash_skb(newhash, key, NULL, skb); 891 if (genhash || memcmp(hash_location, newhash, 16) != 0) 892 goto release_sk1; 893 } 894 #endif 895 896 if (th->ack) 897 seq = ntohl(th->ack_seq); 898 else 899 ack_seq = ntohl(th->seq) + th->syn + th->fin + skb->len - 900 (th->doff << 2); 901 902 oif = sk ? sk->sk_bound_dev_if : 0; 903 tcp_v6_send_response(sk, skb, seq, ack_seq, 0, 0, 0, oif, key, 1, 0, 0); 904 905 #ifdef CONFIG_TCP_MD5SIG 906 release_sk1: 907 if (sk1) { 908 rcu_read_unlock(); 909 sock_put(sk1); 910 } 911 #endif 912 } 913 914 static void tcp_v6_send_ack(const struct sock *sk, struct sk_buff *skb, u32 seq, 915 u32 ack, u32 win, u32 tsval, u32 tsecr, int oif, 916 struct tcp_md5sig_key *key, u8 tclass, 917 u32 label) 918 { 919 tcp_v6_send_response(sk, skb, seq, ack, win, tsval, tsecr, oif, key, 0, 920 tclass, label); 921 } 922 923 static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb) 924 { 925 struct inet_timewait_sock *tw = inet_twsk(sk); 926 struct tcp_timewait_sock *tcptw = tcp_twsk(sk); 927 928 tcp_v6_send_ack(sk, skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt, 929 tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale, 930 tcp_time_stamp + tcptw->tw_ts_offset, 931 tcptw->tw_ts_recent, tw->tw_bound_dev_if, tcp_twsk_md5_key(tcptw), 932 tw->tw_tclass, cpu_to_be32(tw->tw_flowlabel)); 933 934 inet_twsk_put(tw); 935 } 936 937 static void tcp_v6_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, 938 struct request_sock *req) 939 { 940 /* sk->sk_state == TCP_LISTEN -> for regular TCP_SYN_RECV 941 * sk->sk_state == TCP_SYN_RECV -> for Fast Open. 942 */ 943 tcp_v6_send_ack(sk, skb, (sk->sk_state == TCP_LISTEN) ? 944 tcp_rsk(req)->snt_isn + 1 : tcp_sk(sk)->snd_nxt, 945 tcp_rsk(req)->rcv_nxt, req->rsk_rcv_wnd, 946 tcp_time_stamp, req->ts_recent, sk->sk_bound_dev_if, 947 tcp_v6_md5_do_lookup(sk, &ipv6_hdr(skb)->daddr), 948 0, 0); 949 } 950 951 952 static struct sock *tcp_v6_cookie_check(struct sock *sk, struct sk_buff *skb) 953 { 954 #ifdef CONFIG_SYN_COOKIES 955 const struct tcphdr *th = tcp_hdr(skb); 956 957 if (!th->syn) 958 sk = cookie_v6_check(sk, skb); 959 #endif 960 return sk; 961 } 962 963 static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb) 964 { 965 if (skb->protocol == htons(ETH_P_IP)) 966 return tcp_v4_conn_request(sk, skb); 967 968 if (!ipv6_unicast_destination(skb)) 969 goto drop; 970 971 return tcp_conn_request(&tcp6_request_sock_ops, 972 &tcp_request_sock_ipv6_ops, sk, skb); 973 974 drop: 975 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS); 976 return 0; /* don't send reset */ 977 } 978 979 static struct sock *tcp_v6_syn_recv_sock(const struct sock *sk, struct sk_buff *skb, 980 struct request_sock *req, 981 struct dst_entry *dst, 982 struct request_sock *req_unhash, 983 bool *own_req) 984 { 985 struct inet_request_sock *ireq; 986 struct ipv6_pinfo *newnp; 987 const struct ipv6_pinfo *np = inet6_sk(sk); 988 struct ipv6_txoptions *opt; 989 struct tcp6_sock *newtcp6sk; 990 struct inet_sock *newinet; 991 struct tcp_sock *newtp; 992 struct sock *newsk; 993 #ifdef CONFIG_TCP_MD5SIG 994 struct tcp_md5sig_key *key; 995 #endif 996 struct flowi6 fl6; 997 998 if (skb->protocol == htons(ETH_P_IP)) { 999 /* 1000 * v6 mapped 1001 */ 1002 1003 newsk = tcp_v4_syn_recv_sock(sk, skb, req, dst, 1004 req_unhash, own_req); 1005 1006 if (!newsk) 1007 return NULL; 1008 1009 newtcp6sk = (struct tcp6_sock *)newsk; 1010 inet_sk(newsk)->pinet6 = &newtcp6sk->inet6; 1011 1012 newinet = inet_sk(newsk); 1013 newnp = inet6_sk(newsk); 1014 newtp = tcp_sk(newsk); 1015 1016 memcpy(newnp, np, sizeof(struct ipv6_pinfo)); 1017 1018 newnp->saddr = newsk->sk_v6_rcv_saddr; 1019 1020 inet_csk(newsk)->icsk_af_ops = &ipv6_mapped; 1021 newsk->sk_backlog_rcv = tcp_v4_do_rcv; 1022 #ifdef CONFIG_TCP_MD5SIG 1023 newtp->af_specific = &tcp_sock_ipv6_mapped_specific; 1024 #endif 1025 1026 newnp->ipv6_ac_list = NULL; 1027 newnp->ipv6_fl_list = NULL; 1028 newnp->pktoptions = NULL; 1029 newnp->opt = NULL; 1030 newnp->mcast_oif = tcp_v6_iif(skb); 1031 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit; 1032 newnp->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(skb)); 1033 if (np->repflow) 1034 newnp->flow_label = ip6_flowlabel(ipv6_hdr(skb)); 1035 1036 /* 1037 * No need to charge this sock to the relevant IPv6 refcnt debug socks count 1038 * here, tcp_create_openreq_child now does this for us, see the comment in 1039 * that function for the gory details. -acme 1040 */ 1041 1042 /* It is tricky place. Until this moment IPv4 tcp 1043 worked with IPv6 icsk.icsk_af_ops. 1044 Sync it now. 1045 */ 1046 tcp_sync_mss(newsk, inet_csk(newsk)->icsk_pmtu_cookie); 1047 1048 return newsk; 1049 } 1050 1051 ireq = inet_rsk(req); 1052 1053 if (sk_acceptq_is_full(sk)) 1054 goto out_overflow; 1055 1056 if (!dst) { 1057 dst = inet6_csk_route_req(sk, &fl6, req, IPPROTO_TCP); 1058 if (!dst) 1059 goto out; 1060 } 1061 1062 newsk = tcp_create_openreq_child(sk, req, skb); 1063 if (!newsk) 1064 goto out_nonewsk; 1065 1066 /* 1067 * No need to charge this sock to the relevant IPv6 refcnt debug socks 1068 * count here, tcp_create_openreq_child now does this for us, see the 1069 * comment in that function for the gory details. -acme 1070 */ 1071 1072 newsk->sk_gso_type = SKB_GSO_TCPV6; 1073 ip6_dst_store(newsk, dst, NULL, NULL); 1074 inet6_sk_rx_dst_set(newsk, skb); 1075 1076 newtcp6sk = (struct tcp6_sock *)newsk; 1077 inet_sk(newsk)->pinet6 = &newtcp6sk->inet6; 1078 1079 newtp = tcp_sk(newsk); 1080 newinet = inet_sk(newsk); 1081 newnp = inet6_sk(newsk); 1082 1083 memcpy(newnp, np, sizeof(struct ipv6_pinfo)); 1084 1085 newsk->sk_v6_daddr = ireq->ir_v6_rmt_addr; 1086 newnp->saddr = ireq->ir_v6_loc_addr; 1087 newsk->sk_v6_rcv_saddr = ireq->ir_v6_loc_addr; 1088 newsk->sk_bound_dev_if = ireq->ir_iif; 1089 1090 /* Now IPv6 options... 1091 1092 First: no IPv4 options. 1093 */ 1094 newinet->inet_opt = NULL; 1095 newnp->ipv6_ac_list = NULL; 1096 newnp->ipv6_fl_list = NULL; 1097 1098 /* Clone RX bits */ 1099 newnp->rxopt.all = np->rxopt.all; 1100 1101 newnp->pktoptions = NULL; 1102 newnp->opt = NULL; 1103 newnp->mcast_oif = tcp_v6_iif(skb); 1104 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit; 1105 newnp->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(skb)); 1106 if (np->repflow) 1107 newnp->flow_label = ip6_flowlabel(ipv6_hdr(skb)); 1108 1109 /* Clone native IPv6 options from listening socket (if any) 1110 1111 Yes, keeping reference count would be much more clever, 1112 but we make one more one thing there: reattach optmem 1113 to newsk. 1114 */ 1115 opt = rcu_dereference(np->opt); 1116 if (opt) { 1117 opt = ipv6_dup_options(newsk, opt); 1118 RCU_INIT_POINTER(newnp->opt, opt); 1119 } 1120 inet_csk(newsk)->icsk_ext_hdr_len = 0; 1121 if (opt) 1122 inet_csk(newsk)->icsk_ext_hdr_len = opt->opt_nflen + 1123 opt->opt_flen; 1124 1125 tcp_ca_openreq_child(newsk, dst); 1126 1127 tcp_sync_mss(newsk, dst_mtu(dst)); 1128 newtp->advmss = dst_metric_advmss(dst); 1129 if (tcp_sk(sk)->rx_opt.user_mss && 1130 tcp_sk(sk)->rx_opt.user_mss < newtp->advmss) 1131 newtp->advmss = tcp_sk(sk)->rx_opt.user_mss; 1132 1133 tcp_initialize_rcv_mss(newsk); 1134 1135 newinet->inet_daddr = newinet->inet_saddr = LOOPBACK4_IPV6; 1136 newinet->inet_rcv_saddr = LOOPBACK4_IPV6; 1137 1138 #ifdef CONFIG_TCP_MD5SIG 1139 /* Copy over the MD5 key from the original socket */ 1140 key = tcp_v6_md5_do_lookup(sk, &newsk->sk_v6_daddr); 1141 if (key) { 1142 /* We're using one, so create a matching key 1143 * on the newsk structure. If we fail to get 1144 * memory, then we end up not copying the key 1145 * across. Shucks. 1146 */ 1147 tcp_md5_do_add(newsk, (union tcp_md5_addr *)&newsk->sk_v6_daddr, 1148 AF_INET6, key->key, key->keylen, 1149 sk_gfp_mask(sk, GFP_ATOMIC)); 1150 } 1151 #endif 1152 1153 if (__inet_inherit_port(sk, newsk) < 0) { 1154 inet_csk_prepare_forced_close(newsk); 1155 tcp_done(newsk); 1156 goto out; 1157 } 1158 *own_req = inet_ehash_nolisten(newsk, req_to_sk(req_unhash)); 1159 if (*own_req) { 1160 tcp_move_syn(newtp, req); 1161 1162 /* Clone pktoptions received with SYN, if we own the req */ 1163 if (ireq->pktopts) { 1164 newnp->pktoptions = skb_clone(ireq->pktopts, 1165 sk_gfp_mask(sk, GFP_ATOMIC)); 1166 consume_skb(ireq->pktopts); 1167 ireq->pktopts = NULL; 1168 if (newnp->pktoptions) 1169 skb_set_owner_r(newnp->pktoptions, newsk); 1170 } 1171 } 1172 1173 return newsk; 1174 1175 out_overflow: 1176 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS); 1177 out_nonewsk: 1178 dst_release(dst); 1179 out: 1180 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS); 1181 return NULL; 1182 } 1183 1184 /* The socket must have it's spinlock held when we get 1185 * here, unless it is a TCP_LISTEN socket. 1186 * 1187 * We have a potential double-lock case here, so even when 1188 * doing backlog processing we use the BH locking scheme. 1189 * This is because we cannot sleep with the original spinlock 1190 * held. 1191 */ 1192 static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) 1193 { 1194 struct ipv6_pinfo *np = inet6_sk(sk); 1195 struct tcp_sock *tp; 1196 struct sk_buff *opt_skb = NULL; 1197 1198 /* Imagine: socket is IPv6. IPv4 packet arrives, 1199 goes to IPv4 receive handler and backlogged. 1200 From backlog it always goes here. Kerboom... 1201 Fortunately, tcp_rcv_established and rcv_established 1202 handle them correctly, but it is not case with 1203 tcp_v6_hnd_req and tcp_v6_send_reset(). --ANK 1204 */ 1205 1206 if (skb->protocol == htons(ETH_P_IP)) 1207 return tcp_v4_do_rcv(sk, skb); 1208 1209 if (sk_filter(sk, skb)) 1210 goto discard; 1211 1212 /* 1213 * socket locking is here for SMP purposes as backlog rcv 1214 * is currently called with bh processing disabled. 1215 */ 1216 1217 /* Do Stevens' IPV6_PKTOPTIONS. 1218 1219 Yes, guys, it is the only place in our code, where we 1220 may make it not affecting IPv4. 1221 The rest of code is protocol independent, 1222 and I do not like idea to uglify IPv4. 1223 1224 Actually, all the idea behind IPV6_PKTOPTIONS 1225 looks not very well thought. For now we latch 1226 options, received in the last packet, enqueued 1227 by tcp. Feel free to propose better solution. 1228 --ANK (980728) 1229 */ 1230 if (np->rxopt.all) 1231 opt_skb = skb_clone(skb, sk_gfp_mask(sk, GFP_ATOMIC)); 1232 1233 if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */ 1234 struct dst_entry *dst = sk->sk_rx_dst; 1235 1236 sock_rps_save_rxhash(sk, skb); 1237 sk_mark_napi_id(sk, skb); 1238 if (dst) { 1239 if (inet_sk(sk)->rx_dst_ifindex != skb->skb_iif || 1240 dst->ops->check(dst, np->rx_dst_cookie) == NULL) { 1241 dst_release(dst); 1242 sk->sk_rx_dst = NULL; 1243 } 1244 } 1245 1246 tcp_rcv_established(sk, skb, tcp_hdr(skb), skb->len); 1247 if (opt_skb) 1248 goto ipv6_pktoptions; 1249 return 0; 1250 } 1251 1252 if (tcp_checksum_complete(skb)) 1253 goto csum_err; 1254 1255 if (sk->sk_state == TCP_LISTEN) { 1256 struct sock *nsk = tcp_v6_cookie_check(sk, skb); 1257 1258 if (!nsk) 1259 goto discard; 1260 1261 if (nsk != sk) { 1262 sock_rps_save_rxhash(nsk, skb); 1263 sk_mark_napi_id(nsk, skb); 1264 if (tcp_child_process(sk, nsk, skb)) 1265 goto reset; 1266 if (opt_skb) 1267 __kfree_skb(opt_skb); 1268 return 0; 1269 } 1270 } else 1271 sock_rps_save_rxhash(sk, skb); 1272 1273 if (tcp_rcv_state_process(sk, skb)) 1274 goto reset; 1275 if (opt_skb) 1276 goto ipv6_pktoptions; 1277 return 0; 1278 1279 reset: 1280 tcp_v6_send_reset(sk, skb); 1281 discard: 1282 if (opt_skb) 1283 __kfree_skb(opt_skb); 1284 kfree_skb(skb); 1285 return 0; 1286 csum_err: 1287 TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_CSUMERRORS); 1288 TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_INERRS); 1289 goto discard; 1290 1291 1292 ipv6_pktoptions: 1293 /* Do you ask, what is it? 1294 1295 1. skb was enqueued by tcp. 1296 2. skb is added to tail of read queue, rather than out of order. 1297 3. socket is not in passive state. 1298 4. Finally, it really contains options, which user wants to receive. 1299 */ 1300 tp = tcp_sk(sk); 1301 if (TCP_SKB_CB(opt_skb)->end_seq == tp->rcv_nxt && 1302 !((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))) { 1303 if (np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo) 1304 np->mcast_oif = tcp_v6_iif(opt_skb); 1305 if (np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) 1306 np->mcast_hops = ipv6_hdr(opt_skb)->hop_limit; 1307 if (np->rxopt.bits.rxflow || np->rxopt.bits.rxtclass) 1308 np->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(opt_skb)); 1309 if (np->repflow) 1310 np->flow_label = ip6_flowlabel(ipv6_hdr(opt_skb)); 1311 if (ipv6_opt_accepted(sk, opt_skb, &TCP_SKB_CB(opt_skb)->header.h6)) { 1312 skb_set_owner_r(opt_skb, sk); 1313 opt_skb = xchg(&np->pktoptions, opt_skb); 1314 } else { 1315 __kfree_skb(opt_skb); 1316 opt_skb = xchg(&np->pktoptions, NULL); 1317 } 1318 } 1319 1320 kfree_skb(opt_skb); 1321 return 0; 1322 } 1323 1324 static void tcp_v6_fill_cb(struct sk_buff *skb, const struct ipv6hdr *hdr, 1325 const struct tcphdr *th) 1326 { 1327 /* This is tricky: we move IP6CB at its correct location into 1328 * TCP_SKB_CB(). It must be done after xfrm6_policy_check(), because 1329 * _decode_session6() uses IP6CB(). 1330 * barrier() makes sure compiler won't play aliasing games. 1331 */ 1332 memmove(&TCP_SKB_CB(skb)->header.h6, IP6CB(skb), 1333 sizeof(struct inet6_skb_parm)); 1334 barrier(); 1335 1336 TCP_SKB_CB(skb)->seq = ntohl(th->seq); 1337 TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin + 1338 skb->len - th->doff*4); 1339 TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq); 1340 TCP_SKB_CB(skb)->tcp_flags = tcp_flag_byte(th); 1341 TCP_SKB_CB(skb)->tcp_tw_isn = 0; 1342 TCP_SKB_CB(skb)->ip_dsfield = ipv6_get_dsfield(hdr); 1343 TCP_SKB_CB(skb)->sacked = 0; 1344 } 1345 1346 static void tcp_v6_restore_cb(struct sk_buff *skb) 1347 { 1348 /* We need to move header back to the beginning if xfrm6_policy_check() 1349 * and tcp_v6_fill_cb() are going to be called again. 1350 */ 1351 memmove(IP6CB(skb), &TCP_SKB_CB(skb)->header.h6, 1352 sizeof(struct inet6_skb_parm)); 1353 } 1354 1355 static int tcp_v6_rcv(struct sk_buff *skb) 1356 { 1357 const struct tcphdr *th; 1358 const struct ipv6hdr *hdr; 1359 struct sock *sk; 1360 int ret; 1361 struct net *net = dev_net(skb->dev); 1362 1363 if (skb->pkt_type != PACKET_HOST) 1364 goto discard_it; 1365 1366 /* 1367 * Count it even if it's bad. 1368 */ 1369 TCP_INC_STATS_BH(net, TCP_MIB_INSEGS); 1370 1371 if (!pskb_may_pull(skb, sizeof(struct tcphdr))) 1372 goto discard_it; 1373 1374 th = tcp_hdr(skb); 1375 1376 if (th->doff < sizeof(struct tcphdr)/4) 1377 goto bad_packet; 1378 if (!pskb_may_pull(skb, th->doff*4)) 1379 goto discard_it; 1380 1381 if (skb_checksum_init(skb, IPPROTO_TCP, ip6_compute_pseudo)) 1382 goto csum_error; 1383 1384 th = tcp_hdr(skb); 1385 hdr = ipv6_hdr(skb); 1386 1387 lookup: 1388 sk = __inet6_lookup_skb(&tcp_hashinfo, skb, __tcp_hdrlen(th), 1389 th->source, th->dest, inet6_iif(skb)); 1390 if (!sk) 1391 goto no_tcp_socket; 1392 1393 process: 1394 if (sk->sk_state == TCP_TIME_WAIT) 1395 goto do_time_wait; 1396 1397 if (sk->sk_state == TCP_NEW_SYN_RECV) { 1398 struct request_sock *req = inet_reqsk(sk); 1399 struct sock *nsk; 1400 1401 sk = req->rsk_listener; 1402 tcp_v6_fill_cb(skb, hdr, th); 1403 if (tcp_v6_inbound_md5_hash(sk, skb)) { 1404 reqsk_put(req); 1405 goto discard_it; 1406 } 1407 if (unlikely(sk->sk_state != TCP_LISTEN)) { 1408 inet_csk_reqsk_queue_drop_and_put(sk, req); 1409 goto lookup; 1410 } 1411 sock_hold(sk); 1412 nsk = tcp_check_req(sk, skb, req, false); 1413 if (!nsk) { 1414 reqsk_put(req); 1415 goto discard_and_relse; 1416 } 1417 if (nsk == sk) { 1418 reqsk_put(req); 1419 tcp_v6_restore_cb(skb); 1420 } else if (tcp_child_process(sk, nsk, skb)) { 1421 tcp_v6_send_reset(nsk, skb); 1422 goto discard_and_relse; 1423 } else { 1424 sock_put(sk); 1425 return 0; 1426 } 1427 } 1428 if (hdr->hop_limit < inet6_sk(sk)->min_hopcount) { 1429 NET_INC_STATS_BH(net, LINUX_MIB_TCPMINTTLDROP); 1430 goto discard_and_relse; 1431 } 1432 1433 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) 1434 goto discard_and_relse; 1435 1436 tcp_v6_fill_cb(skb, hdr, th); 1437 1438 if (tcp_v6_inbound_md5_hash(sk, skb)) 1439 goto discard_and_relse; 1440 1441 if (sk_filter(sk, skb)) 1442 goto discard_and_relse; 1443 1444 skb->dev = NULL; 1445 1446 if (sk->sk_state == TCP_LISTEN) { 1447 ret = tcp_v6_do_rcv(sk, skb); 1448 goto put_and_return; 1449 } 1450 1451 sk_incoming_cpu_update(sk); 1452 1453 bh_lock_sock_nested(sk); 1454 tcp_segs_in(tcp_sk(sk), skb); 1455 ret = 0; 1456 if (!sock_owned_by_user(sk)) { 1457 if (!tcp_prequeue(sk, skb)) 1458 ret = tcp_v6_do_rcv(sk, skb); 1459 } else if (unlikely(sk_add_backlog(sk, skb, 1460 sk->sk_rcvbuf + sk->sk_sndbuf))) { 1461 bh_unlock_sock(sk); 1462 NET_INC_STATS_BH(net, LINUX_MIB_TCPBACKLOGDROP); 1463 goto discard_and_relse; 1464 } 1465 bh_unlock_sock(sk); 1466 1467 put_and_return: 1468 sock_put(sk); 1469 return ret ? -1 : 0; 1470 1471 no_tcp_socket: 1472 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 1473 goto discard_it; 1474 1475 tcp_v6_fill_cb(skb, hdr, th); 1476 1477 if (tcp_checksum_complete(skb)) { 1478 csum_error: 1479 TCP_INC_STATS_BH(net, TCP_MIB_CSUMERRORS); 1480 bad_packet: 1481 TCP_INC_STATS_BH(net, TCP_MIB_INERRS); 1482 } else { 1483 tcp_v6_send_reset(NULL, skb); 1484 } 1485 1486 discard_it: 1487 kfree_skb(skb); 1488 return 0; 1489 1490 discard_and_relse: 1491 sock_put(sk); 1492 goto discard_it; 1493 1494 do_time_wait: 1495 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) { 1496 inet_twsk_put(inet_twsk(sk)); 1497 goto discard_it; 1498 } 1499 1500 tcp_v6_fill_cb(skb, hdr, th); 1501 1502 if (tcp_checksum_complete(skb)) { 1503 inet_twsk_put(inet_twsk(sk)); 1504 goto csum_error; 1505 } 1506 1507 switch (tcp_timewait_state_process(inet_twsk(sk), skb, th)) { 1508 case TCP_TW_SYN: 1509 { 1510 struct sock *sk2; 1511 1512 sk2 = inet6_lookup_listener(dev_net(skb->dev), &tcp_hashinfo, 1513 skb, __tcp_hdrlen(th), 1514 &ipv6_hdr(skb)->saddr, th->source, 1515 &ipv6_hdr(skb)->daddr, 1516 ntohs(th->dest), tcp_v6_iif(skb)); 1517 if (sk2) { 1518 struct inet_timewait_sock *tw = inet_twsk(sk); 1519 inet_twsk_deschedule_put(tw); 1520 sk = sk2; 1521 tcp_v6_restore_cb(skb); 1522 goto process; 1523 } 1524 /* Fall through to ACK */ 1525 } 1526 case TCP_TW_ACK: 1527 tcp_v6_timewait_ack(sk, skb); 1528 break; 1529 case TCP_TW_RST: 1530 tcp_v6_restore_cb(skb); 1531 tcp_v6_send_reset(sk, skb); 1532 inet_twsk_deschedule_put(inet_twsk(sk)); 1533 goto discard_it; 1534 case TCP_TW_SUCCESS: 1535 ; 1536 } 1537 goto discard_it; 1538 } 1539 1540 static void tcp_v6_early_demux(struct sk_buff *skb) 1541 { 1542 const struct ipv6hdr *hdr; 1543 const struct tcphdr *th; 1544 struct sock *sk; 1545 1546 if (skb->pkt_type != PACKET_HOST) 1547 return; 1548 1549 if (!pskb_may_pull(skb, skb_transport_offset(skb) + sizeof(struct tcphdr))) 1550 return; 1551 1552 hdr = ipv6_hdr(skb); 1553 th = tcp_hdr(skb); 1554 1555 if (th->doff < sizeof(struct tcphdr) / 4) 1556 return; 1557 1558 /* Note : We use inet6_iif() here, not tcp_v6_iif() */ 1559 sk = __inet6_lookup_established(dev_net(skb->dev), &tcp_hashinfo, 1560 &hdr->saddr, th->source, 1561 &hdr->daddr, ntohs(th->dest), 1562 inet6_iif(skb)); 1563 if (sk) { 1564 skb->sk = sk; 1565 skb->destructor = sock_edemux; 1566 if (sk_fullsock(sk)) { 1567 struct dst_entry *dst = READ_ONCE(sk->sk_rx_dst); 1568 1569 if (dst) 1570 dst = dst_check(dst, inet6_sk(sk)->rx_dst_cookie); 1571 if (dst && 1572 inet_sk(sk)->rx_dst_ifindex == skb->skb_iif) 1573 skb_dst_set_noref(skb, dst); 1574 } 1575 } 1576 } 1577 1578 static struct timewait_sock_ops tcp6_timewait_sock_ops = { 1579 .twsk_obj_size = sizeof(struct tcp6_timewait_sock), 1580 .twsk_unique = tcp_twsk_unique, 1581 .twsk_destructor = tcp_twsk_destructor, 1582 }; 1583 1584 static const struct inet_connection_sock_af_ops ipv6_specific = { 1585 .queue_xmit = inet6_csk_xmit, 1586 .send_check = tcp_v6_send_check, 1587 .rebuild_header = inet6_sk_rebuild_header, 1588 .sk_rx_dst_set = inet6_sk_rx_dst_set, 1589 .conn_request = tcp_v6_conn_request, 1590 .syn_recv_sock = tcp_v6_syn_recv_sock, 1591 .net_header_len = sizeof(struct ipv6hdr), 1592 .net_frag_header_len = sizeof(struct frag_hdr), 1593 .setsockopt = ipv6_setsockopt, 1594 .getsockopt = ipv6_getsockopt, 1595 .addr2sockaddr = inet6_csk_addr2sockaddr, 1596 .sockaddr_len = sizeof(struct sockaddr_in6), 1597 .bind_conflict = inet6_csk_bind_conflict, 1598 #ifdef CONFIG_COMPAT 1599 .compat_setsockopt = compat_ipv6_setsockopt, 1600 .compat_getsockopt = compat_ipv6_getsockopt, 1601 #endif 1602 .mtu_reduced = tcp_v6_mtu_reduced, 1603 }; 1604 1605 #ifdef CONFIG_TCP_MD5SIG 1606 static const struct tcp_sock_af_ops tcp_sock_ipv6_specific = { 1607 .md5_lookup = tcp_v6_md5_lookup, 1608 .calc_md5_hash = tcp_v6_md5_hash_skb, 1609 .md5_parse = tcp_v6_parse_md5_keys, 1610 }; 1611 #endif 1612 1613 /* 1614 * TCP over IPv4 via INET6 API 1615 */ 1616 static const struct inet_connection_sock_af_ops ipv6_mapped = { 1617 .queue_xmit = ip_queue_xmit, 1618 .send_check = tcp_v4_send_check, 1619 .rebuild_header = inet_sk_rebuild_header, 1620 .sk_rx_dst_set = inet_sk_rx_dst_set, 1621 .conn_request = tcp_v6_conn_request, 1622 .syn_recv_sock = tcp_v6_syn_recv_sock, 1623 .net_header_len = sizeof(struct iphdr), 1624 .setsockopt = ipv6_setsockopt, 1625 .getsockopt = ipv6_getsockopt, 1626 .addr2sockaddr = inet6_csk_addr2sockaddr, 1627 .sockaddr_len = sizeof(struct sockaddr_in6), 1628 .bind_conflict = inet6_csk_bind_conflict, 1629 #ifdef CONFIG_COMPAT 1630 .compat_setsockopt = compat_ipv6_setsockopt, 1631 .compat_getsockopt = compat_ipv6_getsockopt, 1632 #endif 1633 .mtu_reduced = tcp_v4_mtu_reduced, 1634 }; 1635 1636 #ifdef CONFIG_TCP_MD5SIG 1637 static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific = { 1638 .md5_lookup = tcp_v4_md5_lookup, 1639 .calc_md5_hash = tcp_v4_md5_hash_skb, 1640 .md5_parse = tcp_v6_parse_md5_keys, 1641 }; 1642 #endif 1643 1644 /* NOTE: A lot of things set to zero explicitly by call to 1645 * sk_alloc() so need not be done here. 1646 */ 1647 static int tcp_v6_init_sock(struct sock *sk) 1648 { 1649 struct inet_connection_sock *icsk = inet_csk(sk); 1650 1651 tcp_init_sock(sk); 1652 1653 icsk->icsk_af_ops = &ipv6_specific; 1654 1655 #ifdef CONFIG_TCP_MD5SIG 1656 tcp_sk(sk)->af_specific = &tcp_sock_ipv6_specific; 1657 #endif 1658 1659 return 0; 1660 } 1661 1662 static void tcp_v6_destroy_sock(struct sock *sk) 1663 { 1664 tcp_v4_destroy_sock(sk); 1665 inet6_destroy_sock(sk); 1666 } 1667 1668 #ifdef CONFIG_PROC_FS 1669 /* Proc filesystem TCPv6 sock list dumping. */ 1670 static void get_openreq6(struct seq_file *seq, 1671 const struct request_sock *req, int i) 1672 { 1673 long ttd = req->rsk_timer.expires - jiffies; 1674 const struct in6_addr *src = &inet_rsk(req)->ir_v6_loc_addr; 1675 const struct in6_addr *dest = &inet_rsk(req)->ir_v6_rmt_addr; 1676 1677 if (ttd < 0) 1678 ttd = 0; 1679 1680 seq_printf(seq, 1681 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1682 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %d %d %pK\n", 1683 i, 1684 src->s6_addr32[0], src->s6_addr32[1], 1685 src->s6_addr32[2], src->s6_addr32[3], 1686 inet_rsk(req)->ir_num, 1687 dest->s6_addr32[0], dest->s6_addr32[1], 1688 dest->s6_addr32[2], dest->s6_addr32[3], 1689 ntohs(inet_rsk(req)->ir_rmt_port), 1690 TCP_SYN_RECV, 1691 0, 0, /* could print option size, but that is af dependent. */ 1692 1, /* timers active (only the expire timer) */ 1693 jiffies_to_clock_t(ttd), 1694 req->num_timeout, 1695 from_kuid_munged(seq_user_ns(seq), 1696 sock_i_uid(req->rsk_listener)), 1697 0, /* non standard timer */ 1698 0, /* open_requests have no inode */ 1699 0, req); 1700 } 1701 1702 static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i) 1703 { 1704 const struct in6_addr *dest, *src; 1705 __u16 destp, srcp; 1706 int timer_active; 1707 unsigned long timer_expires; 1708 const struct inet_sock *inet = inet_sk(sp); 1709 const struct tcp_sock *tp = tcp_sk(sp); 1710 const struct inet_connection_sock *icsk = inet_csk(sp); 1711 const struct fastopen_queue *fastopenq = &icsk->icsk_accept_queue.fastopenq; 1712 int rx_queue; 1713 int state; 1714 1715 dest = &sp->sk_v6_daddr; 1716 src = &sp->sk_v6_rcv_saddr; 1717 destp = ntohs(inet->inet_dport); 1718 srcp = ntohs(inet->inet_sport); 1719 1720 if (icsk->icsk_pending == ICSK_TIME_RETRANS) { 1721 timer_active = 1; 1722 timer_expires = icsk->icsk_timeout; 1723 } else if (icsk->icsk_pending == ICSK_TIME_PROBE0) { 1724 timer_active = 4; 1725 timer_expires = icsk->icsk_timeout; 1726 } else if (timer_pending(&sp->sk_timer)) { 1727 timer_active = 2; 1728 timer_expires = sp->sk_timer.expires; 1729 } else { 1730 timer_active = 0; 1731 timer_expires = jiffies; 1732 } 1733 1734 state = sk_state_load(sp); 1735 if (state == TCP_LISTEN) 1736 rx_queue = sp->sk_ack_backlog; 1737 else 1738 /* Because we don't lock the socket, 1739 * we might find a transient negative value. 1740 */ 1741 rx_queue = max_t(int, tp->rcv_nxt - tp->copied_seq, 0); 1742 1743 seq_printf(seq, 1744 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1745 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %lu %lu %u %u %d\n", 1746 i, 1747 src->s6_addr32[0], src->s6_addr32[1], 1748 src->s6_addr32[2], src->s6_addr32[3], srcp, 1749 dest->s6_addr32[0], dest->s6_addr32[1], 1750 dest->s6_addr32[2], dest->s6_addr32[3], destp, 1751 state, 1752 tp->write_seq - tp->snd_una, 1753 rx_queue, 1754 timer_active, 1755 jiffies_delta_to_clock_t(timer_expires - jiffies), 1756 icsk->icsk_retransmits, 1757 from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)), 1758 icsk->icsk_probes_out, 1759 sock_i_ino(sp), 1760 atomic_read(&sp->sk_refcnt), sp, 1761 jiffies_to_clock_t(icsk->icsk_rto), 1762 jiffies_to_clock_t(icsk->icsk_ack.ato), 1763 (icsk->icsk_ack.quick << 1) | icsk->icsk_ack.pingpong, 1764 tp->snd_cwnd, 1765 state == TCP_LISTEN ? 1766 fastopenq->max_qlen : 1767 (tcp_in_initial_slowstart(tp) ? -1 : tp->snd_ssthresh) 1768 ); 1769 } 1770 1771 static void get_timewait6_sock(struct seq_file *seq, 1772 struct inet_timewait_sock *tw, int i) 1773 { 1774 long delta = tw->tw_timer.expires - jiffies; 1775 const struct in6_addr *dest, *src; 1776 __u16 destp, srcp; 1777 1778 dest = &tw->tw_v6_daddr; 1779 src = &tw->tw_v6_rcv_saddr; 1780 destp = ntohs(tw->tw_dport); 1781 srcp = ntohs(tw->tw_sport); 1782 1783 seq_printf(seq, 1784 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1785 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK\n", 1786 i, 1787 src->s6_addr32[0], src->s6_addr32[1], 1788 src->s6_addr32[2], src->s6_addr32[3], srcp, 1789 dest->s6_addr32[0], dest->s6_addr32[1], 1790 dest->s6_addr32[2], dest->s6_addr32[3], destp, 1791 tw->tw_substate, 0, 0, 1792 3, jiffies_delta_to_clock_t(delta), 0, 0, 0, 0, 1793 atomic_read(&tw->tw_refcnt), tw); 1794 } 1795 1796 static int tcp6_seq_show(struct seq_file *seq, void *v) 1797 { 1798 struct tcp_iter_state *st; 1799 struct sock *sk = v; 1800 1801 if (v == SEQ_START_TOKEN) { 1802 seq_puts(seq, 1803 " sl " 1804 "local_address " 1805 "remote_address " 1806 "st tx_queue rx_queue tr tm->when retrnsmt" 1807 " uid timeout inode\n"); 1808 goto out; 1809 } 1810 st = seq->private; 1811 1812 if (sk->sk_state == TCP_TIME_WAIT) 1813 get_timewait6_sock(seq, v, st->num); 1814 else if (sk->sk_state == TCP_NEW_SYN_RECV) 1815 get_openreq6(seq, v, st->num); 1816 else 1817 get_tcp6_sock(seq, v, st->num); 1818 out: 1819 return 0; 1820 } 1821 1822 static const struct file_operations tcp6_afinfo_seq_fops = { 1823 .owner = THIS_MODULE, 1824 .open = tcp_seq_open, 1825 .read = seq_read, 1826 .llseek = seq_lseek, 1827 .release = seq_release_net 1828 }; 1829 1830 static struct tcp_seq_afinfo tcp6_seq_afinfo = { 1831 .name = "tcp6", 1832 .family = AF_INET6, 1833 .seq_fops = &tcp6_afinfo_seq_fops, 1834 .seq_ops = { 1835 .show = tcp6_seq_show, 1836 }, 1837 }; 1838 1839 int __net_init tcp6_proc_init(struct net *net) 1840 { 1841 return tcp_proc_register(net, &tcp6_seq_afinfo); 1842 } 1843 1844 void tcp6_proc_exit(struct net *net) 1845 { 1846 tcp_proc_unregister(net, &tcp6_seq_afinfo); 1847 } 1848 #endif 1849 1850 static void tcp_v6_clear_sk(struct sock *sk, int size) 1851 { 1852 struct inet_sock *inet = inet_sk(sk); 1853 1854 /* we do not want to clear pinet6 field, because of RCU lookups */ 1855 sk_prot_clear_nulls(sk, offsetof(struct inet_sock, pinet6)); 1856 1857 size -= offsetof(struct inet_sock, pinet6) + sizeof(inet->pinet6); 1858 memset(&inet->pinet6 + 1, 0, size); 1859 } 1860 1861 struct proto tcpv6_prot = { 1862 .name = "TCPv6", 1863 .owner = THIS_MODULE, 1864 .close = tcp_close, 1865 .connect = tcp_v6_connect, 1866 .disconnect = tcp_disconnect, 1867 .accept = inet_csk_accept, 1868 .ioctl = tcp_ioctl, 1869 .init = tcp_v6_init_sock, 1870 .destroy = tcp_v6_destroy_sock, 1871 .shutdown = tcp_shutdown, 1872 .setsockopt = tcp_setsockopt, 1873 .getsockopt = tcp_getsockopt, 1874 .recvmsg = tcp_recvmsg, 1875 .sendmsg = tcp_sendmsg, 1876 .sendpage = tcp_sendpage, 1877 .backlog_rcv = tcp_v6_do_rcv, 1878 .release_cb = tcp_release_cb, 1879 .hash = inet6_hash, 1880 .unhash = inet_unhash, 1881 .get_port = inet_csk_get_port, 1882 .enter_memory_pressure = tcp_enter_memory_pressure, 1883 .stream_memory_free = tcp_stream_memory_free, 1884 .sockets_allocated = &tcp_sockets_allocated, 1885 .memory_allocated = &tcp_memory_allocated, 1886 .memory_pressure = &tcp_memory_pressure, 1887 .orphan_count = &tcp_orphan_count, 1888 .sysctl_mem = sysctl_tcp_mem, 1889 .sysctl_wmem = sysctl_tcp_wmem, 1890 .sysctl_rmem = sysctl_tcp_rmem, 1891 .max_header = MAX_TCP_HEADER, 1892 .obj_size = sizeof(struct tcp6_sock), 1893 .slab_flags = SLAB_DESTROY_BY_RCU, 1894 .twsk_prot = &tcp6_timewait_sock_ops, 1895 .rsk_prot = &tcp6_request_sock_ops, 1896 .h.hashinfo = &tcp_hashinfo, 1897 .no_autobind = true, 1898 #ifdef CONFIG_COMPAT 1899 .compat_setsockopt = compat_tcp_setsockopt, 1900 .compat_getsockopt = compat_tcp_getsockopt, 1901 #endif 1902 .clear_sk = tcp_v6_clear_sk, 1903 .diag_destroy = tcp_abort, 1904 }; 1905 1906 static const struct inet6_protocol tcpv6_protocol = { 1907 .early_demux = tcp_v6_early_demux, 1908 .handler = tcp_v6_rcv, 1909 .err_handler = tcp_v6_err, 1910 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 1911 }; 1912 1913 static struct inet_protosw tcpv6_protosw = { 1914 .type = SOCK_STREAM, 1915 .protocol = IPPROTO_TCP, 1916 .prot = &tcpv6_prot, 1917 .ops = &inet6_stream_ops, 1918 .flags = INET_PROTOSW_PERMANENT | 1919 INET_PROTOSW_ICSK, 1920 }; 1921 1922 static int __net_init tcpv6_net_init(struct net *net) 1923 { 1924 return inet_ctl_sock_create(&net->ipv6.tcp_sk, PF_INET6, 1925 SOCK_RAW, IPPROTO_TCP, net); 1926 } 1927 1928 static void __net_exit tcpv6_net_exit(struct net *net) 1929 { 1930 inet_ctl_sock_destroy(net->ipv6.tcp_sk); 1931 } 1932 1933 static void __net_exit tcpv6_net_exit_batch(struct list_head *net_exit_list) 1934 { 1935 inet_twsk_purge(&tcp_hashinfo, &tcp_death_row, AF_INET6); 1936 } 1937 1938 static struct pernet_operations tcpv6_net_ops = { 1939 .init = tcpv6_net_init, 1940 .exit = tcpv6_net_exit, 1941 .exit_batch = tcpv6_net_exit_batch, 1942 }; 1943 1944 int __init tcpv6_init(void) 1945 { 1946 int ret; 1947 1948 ret = inet6_add_protocol(&tcpv6_protocol, IPPROTO_TCP); 1949 if (ret) 1950 goto out; 1951 1952 /* register inet6 protocol */ 1953 ret = inet6_register_protosw(&tcpv6_protosw); 1954 if (ret) 1955 goto out_tcpv6_protocol; 1956 1957 ret = register_pernet_subsys(&tcpv6_net_ops); 1958 if (ret) 1959 goto out_tcpv6_protosw; 1960 out: 1961 return ret; 1962 1963 out_tcpv6_protosw: 1964 inet6_unregister_protosw(&tcpv6_protosw); 1965 out_tcpv6_protocol: 1966 inet6_del_protocol(&tcpv6_protocol, IPPROTO_TCP); 1967 goto out; 1968 } 1969 1970 void tcpv6_exit(void) 1971 { 1972 unregister_pernet_subsys(&tcpv6_net_ops); 1973 inet6_unregister_protosw(&tcpv6_protosw); 1974 inet6_del_protocol(&tcpv6_protocol, IPPROTO_TCP); 1975 } 1976