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 fl6.flowi6_oif = oif; 815 fl6.flowi6_mark = IP6_REPLY_MARK(net, skb->mark); 816 fl6.fl6_dport = t1->dest; 817 fl6.fl6_sport = t1->source; 818 security_skb_classify_flow(skb, flowi6_to_flowi(&fl6)); 819 820 /* Pass a socket to ip6_dst_lookup either it is for RST 821 * Underlying function will use this to retrieve the network 822 * namespace 823 */ 824 dst = ip6_dst_lookup_flow(ctl_sk, &fl6, NULL); 825 if (!IS_ERR(dst)) { 826 skb_dst_set(buff, dst); 827 ip6_xmit(ctl_sk, buff, &fl6, NULL, tclass); 828 TCP_INC_STATS_BH(net, TCP_MIB_OUTSEGS); 829 if (rst) 830 TCP_INC_STATS_BH(net, TCP_MIB_OUTRSTS); 831 return; 832 } 833 834 kfree_skb(buff); 835 } 836 837 static void tcp_v6_send_reset(const struct sock *sk, struct sk_buff *skb) 838 { 839 const struct tcphdr *th = tcp_hdr(skb); 840 u32 seq = 0, ack_seq = 0; 841 struct tcp_md5sig_key *key = NULL; 842 #ifdef CONFIG_TCP_MD5SIG 843 const __u8 *hash_location = NULL; 844 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 845 unsigned char newhash[16]; 846 int genhash; 847 struct sock *sk1 = NULL; 848 #endif 849 int oif; 850 851 if (th->rst) 852 return; 853 854 /* If sk not NULL, it means we did a successful lookup and incoming 855 * route had to be correct. prequeue might have dropped our dst. 856 */ 857 if (!sk && !ipv6_unicast_destination(skb)) 858 return; 859 860 #ifdef CONFIG_TCP_MD5SIG 861 hash_location = tcp_parse_md5sig_option(th); 862 if (sk && sk_fullsock(sk)) { 863 key = tcp_v6_md5_do_lookup(sk, &ipv6h->saddr); 864 } else if (hash_location) { 865 /* 866 * active side is lost. Try to find listening socket through 867 * source port, and then find md5 key through listening socket. 868 * we are not loose security here: 869 * Incoming packet is checked with md5 hash with finding key, 870 * no RST generated if md5 hash doesn't match. 871 */ 872 sk1 = inet6_lookup_listener(dev_net(skb_dst(skb)->dev), 873 &tcp_hashinfo, &ipv6h->saddr, 874 th->source, &ipv6h->daddr, 875 ntohs(th->source), tcp_v6_iif(skb)); 876 if (!sk1) 877 return; 878 879 rcu_read_lock(); 880 key = tcp_v6_md5_do_lookup(sk1, &ipv6h->saddr); 881 if (!key) 882 goto release_sk1; 883 884 genhash = tcp_v6_md5_hash_skb(newhash, key, NULL, skb); 885 if (genhash || memcmp(hash_location, newhash, 16) != 0) 886 goto release_sk1; 887 } 888 #endif 889 890 if (th->ack) 891 seq = ntohl(th->ack_seq); 892 else 893 ack_seq = ntohl(th->seq) + th->syn + th->fin + skb->len - 894 (th->doff << 2); 895 896 oif = sk ? sk->sk_bound_dev_if : 0; 897 tcp_v6_send_response(sk, skb, seq, ack_seq, 0, 0, 0, oif, key, 1, 0, 0); 898 899 #ifdef CONFIG_TCP_MD5SIG 900 release_sk1: 901 if (sk1) { 902 rcu_read_unlock(); 903 sock_put(sk1); 904 } 905 #endif 906 } 907 908 static void tcp_v6_send_ack(const struct sock *sk, struct sk_buff *skb, u32 seq, 909 u32 ack, u32 win, u32 tsval, u32 tsecr, int oif, 910 struct tcp_md5sig_key *key, u8 tclass, 911 u32 label) 912 { 913 tcp_v6_send_response(sk, skb, seq, ack, win, tsval, tsecr, oif, key, 0, 914 tclass, label); 915 } 916 917 static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb) 918 { 919 struct inet_timewait_sock *tw = inet_twsk(sk); 920 struct tcp_timewait_sock *tcptw = tcp_twsk(sk); 921 922 tcp_v6_send_ack(sk, skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt, 923 tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale, 924 tcp_time_stamp + tcptw->tw_ts_offset, 925 tcptw->tw_ts_recent, tw->tw_bound_dev_if, tcp_twsk_md5_key(tcptw), 926 tw->tw_tclass, cpu_to_be32(tw->tw_flowlabel)); 927 928 inet_twsk_put(tw); 929 } 930 931 static void tcp_v6_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, 932 struct request_sock *req) 933 { 934 /* sk->sk_state == TCP_LISTEN -> for regular TCP_SYN_RECV 935 * sk->sk_state == TCP_SYN_RECV -> for Fast Open. 936 */ 937 tcp_v6_send_ack(sk, skb, (sk->sk_state == TCP_LISTEN) ? 938 tcp_rsk(req)->snt_isn + 1 : tcp_sk(sk)->snd_nxt, 939 tcp_rsk(req)->rcv_nxt, req->rsk_rcv_wnd, 940 tcp_time_stamp, req->ts_recent, sk->sk_bound_dev_if, 941 tcp_v6_md5_do_lookup(sk, &ipv6_hdr(skb)->daddr), 942 0, 0); 943 } 944 945 946 static struct sock *tcp_v6_cookie_check(struct sock *sk, struct sk_buff *skb) 947 { 948 #ifdef CONFIG_SYN_COOKIES 949 const struct tcphdr *th = tcp_hdr(skb); 950 951 if (!th->syn) 952 sk = cookie_v6_check(sk, skb); 953 #endif 954 return sk; 955 } 956 957 static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb) 958 { 959 if (skb->protocol == htons(ETH_P_IP)) 960 return tcp_v4_conn_request(sk, skb); 961 962 if (!ipv6_unicast_destination(skb)) 963 goto drop; 964 965 return tcp_conn_request(&tcp6_request_sock_ops, 966 &tcp_request_sock_ipv6_ops, sk, skb); 967 968 drop: 969 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS); 970 return 0; /* don't send reset */ 971 } 972 973 static struct sock *tcp_v6_syn_recv_sock(const struct sock *sk, struct sk_buff *skb, 974 struct request_sock *req, 975 struct dst_entry *dst, 976 struct request_sock *req_unhash, 977 bool *own_req) 978 { 979 struct inet_request_sock *ireq; 980 struct ipv6_pinfo *newnp; 981 const struct ipv6_pinfo *np = inet6_sk(sk); 982 struct ipv6_txoptions *opt; 983 struct tcp6_sock *newtcp6sk; 984 struct inet_sock *newinet; 985 struct tcp_sock *newtp; 986 struct sock *newsk; 987 #ifdef CONFIG_TCP_MD5SIG 988 struct tcp_md5sig_key *key; 989 #endif 990 struct flowi6 fl6; 991 992 if (skb->protocol == htons(ETH_P_IP)) { 993 /* 994 * v6 mapped 995 */ 996 997 newsk = tcp_v4_syn_recv_sock(sk, skb, req, dst, 998 req_unhash, own_req); 999 1000 if (!newsk) 1001 return NULL; 1002 1003 newtcp6sk = (struct tcp6_sock *)newsk; 1004 inet_sk(newsk)->pinet6 = &newtcp6sk->inet6; 1005 1006 newinet = inet_sk(newsk); 1007 newnp = inet6_sk(newsk); 1008 newtp = tcp_sk(newsk); 1009 1010 memcpy(newnp, np, sizeof(struct ipv6_pinfo)); 1011 1012 newnp->saddr = newsk->sk_v6_rcv_saddr; 1013 1014 inet_csk(newsk)->icsk_af_ops = &ipv6_mapped; 1015 newsk->sk_backlog_rcv = tcp_v4_do_rcv; 1016 #ifdef CONFIG_TCP_MD5SIG 1017 newtp->af_specific = &tcp_sock_ipv6_mapped_specific; 1018 #endif 1019 1020 newnp->ipv6_ac_list = NULL; 1021 newnp->ipv6_fl_list = NULL; 1022 newnp->pktoptions = NULL; 1023 newnp->opt = NULL; 1024 newnp->mcast_oif = tcp_v6_iif(skb); 1025 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit; 1026 newnp->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(skb)); 1027 if (np->repflow) 1028 newnp->flow_label = ip6_flowlabel(ipv6_hdr(skb)); 1029 1030 /* 1031 * No need to charge this sock to the relevant IPv6 refcnt debug socks count 1032 * here, tcp_create_openreq_child now does this for us, see the comment in 1033 * that function for the gory details. -acme 1034 */ 1035 1036 /* It is tricky place. Until this moment IPv4 tcp 1037 worked with IPv6 icsk.icsk_af_ops. 1038 Sync it now. 1039 */ 1040 tcp_sync_mss(newsk, inet_csk(newsk)->icsk_pmtu_cookie); 1041 1042 return newsk; 1043 } 1044 1045 ireq = inet_rsk(req); 1046 1047 if (sk_acceptq_is_full(sk)) 1048 goto out_overflow; 1049 1050 if (!dst) { 1051 dst = inet6_csk_route_req(sk, &fl6, req, IPPROTO_TCP); 1052 if (!dst) 1053 goto out; 1054 } 1055 1056 newsk = tcp_create_openreq_child(sk, req, skb); 1057 if (!newsk) 1058 goto out_nonewsk; 1059 1060 /* 1061 * No need to charge this sock to the relevant IPv6 refcnt debug socks 1062 * count here, tcp_create_openreq_child now does this for us, see the 1063 * comment in that function for the gory details. -acme 1064 */ 1065 1066 newsk->sk_gso_type = SKB_GSO_TCPV6; 1067 ip6_dst_store(newsk, dst, NULL, NULL); 1068 inet6_sk_rx_dst_set(newsk, skb); 1069 1070 newtcp6sk = (struct tcp6_sock *)newsk; 1071 inet_sk(newsk)->pinet6 = &newtcp6sk->inet6; 1072 1073 newtp = tcp_sk(newsk); 1074 newinet = inet_sk(newsk); 1075 newnp = inet6_sk(newsk); 1076 1077 memcpy(newnp, np, sizeof(struct ipv6_pinfo)); 1078 1079 newsk->sk_v6_daddr = ireq->ir_v6_rmt_addr; 1080 newnp->saddr = ireq->ir_v6_loc_addr; 1081 newsk->sk_v6_rcv_saddr = ireq->ir_v6_loc_addr; 1082 newsk->sk_bound_dev_if = ireq->ir_iif; 1083 1084 /* Now IPv6 options... 1085 1086 First: no IPv4 options. 1087 */ 1088 newinet->inet_opt = NULL; 1089 newnp->ipv6_ac_list = NULL; 1090 newnp->ipv6_fl_list = NULL; 1091 1092 /* Clone RX bits */ 1093 newnp->rxopt.all = np->rxopt.all; 1094 1095 newnp->pktoptions = NULL; 1096 newnp->opt = NULL; 1097 newnp->mcast_oif = tcp_v6_iif(skb); 1098 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit; 1099 newnp->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(skb)); 1100 if (np->repflow) 1101 newnp->flow_label = ip6_flowlabel(ipv6_hdr(skb)); 1102 1103 /* Clone native IPv6 options from listening socket (if any) 1104 1105 Yes, keeping reference count would be much more clever, 1106 but we make one more one thing there: reattach optmem 1107 to newsk. 1108 */ 1109 opt = rcu_dereference(np->opt); 1110 if (opt) { 1111 opt = ipv6_dup_options(newsk, opt); 1112 RCU_INIT_POINTER(newnp->opt, opt); 1113 } 1114 inet_csk(newsk)->icsk_ext_hdr_len = 0; 1115 if (opt) 1116 inet_csk(newsk)->icsk_ext_hdr_len = opt->opt_nflen + 1117 opt->opt_flen; 1118 1119 tcp_ca_openreq_child(newsk, dst); 1120 1121 tcp_sync_mss(newsk, dst_mtu(dst)); 1122 newtp->advmss = dst_metric_advmss(dst); 1123 if (tcp_sk(sk)->rx_opt.user_mss && 1124 tcp_sk(sk)->rx_opt.user_mss < newtp->advmss) 1125 newtp->advmss = tcp_sk(sk)->rx_opt.user_mss; 1126 1127 tcp_initialize_rcv_mss(newsk); 1128 1129 newinet->inet_daddr = newinet->inet_saddr = LOOPBACK4_IPV6; 1130 newinet->inet_rcv_saddr = LOOPBACK4_IPV6; 1131 1132 #ifdef CONFIG_TCP_MD5SIG 1133 /* Copy over the MD5 key from the original socket */ 1134 key = tcp_v6_md5_do_lookup(sk, &newsk->sk_v6_daddr); 1135 if (key) { 1136 /* We're using one, so create a matching key 1137 * on the newsk structure. If we fail to get 1138 * memory, then we end up not copying the key 1139 * across. Shucks. 1140 */ 1141 tcp_md5_do_add(newsk, (union tcp_md5_addr *)&newsk->sk_v6_daddr, 1142 AF_INET6, key->key, key->keylen, 1143 sk_gfp_mask(sk, GFP_ATOMIC)); 1144 } 1145 #endif 1146 1147 if (__inet_inherit_port(sk, newsk) < 0) { 1148 inet_csk_prepare_forced_close(newsk); 1149 tcp_done(newsk); 1150 goto out; 1151 } 1152 *own_req = inet_ehash_nolisten(newsk, req_to_sk(req_unhash)); 1153 if (*own_req) { 1154 tcp_move_syn(newtp, req); 1155 1156 /* Clone pktoptions received with SYN, if we own the req */ 1157 if (ireq->pktopts) { 1158 newnp->pktoptions = skb_clone(ireq->pktopts, 1159 sk_gfp_mask(sk, GFP_ATOMIC)); 1160 consume_skb(ireq->pktopts); 1161 ireq->pktopts = NULL; 1162 if (newnp->pktoptions) 1163 skb_set_owner_r(newnp->pktoptions, newsk); 1164 } 1165 } 1166 1167 return newsk; 1168 1169 out_overflow: 1170 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS); 1171 out_nonewsk: 1172 dst_release(dst); 1173 out: 1174 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS); 1175 return NULL; 1176 } 1177 1178 /* The socket must have it's spinlock held when we get 1179 * here, unless it is a TCP_LISTEN socket. 1180 * 1181 * We have a potential double-lock case here, so even when 1182 * doing backlog processing we use the BH locking scheme. 1183 * This is because we cannot sleep with the original spinlock 1184 * held. 1185 */ 1186 static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) 1187 { 1188 struct ipv6_pinfo *np = inet6_sk(sk); 1189 struct tcp_sock *tp; 1190 struct sk_buff *opt_skb = NULL; 1191 1192 /* Imagine: socket is IPv6. IPv4 packet arrives, 1193 goes to IPv4 receive handler and backlogged. 1194 From backlog it always goes here. Kerboom... 1195 Fortunately, tcp_rcv_established and rcv_established 1196 handle them correctly, but it is not case with 1197 tcp_v6_hnd_req and tcp_v6_send_reset(). --ANK 1198 */ 1199 1200 if (skb->protocol == htons(ETH_P_IP)) 1201 return tcp_v4_do_rcv(sk, skb); 1202 1203 if (sk_filter(sk, skb)) 1204 goto discard; 1205 1206 /* 1207 * socket locking is here for SMP purposes as backlog rcv 1208 * is currently called with bh processing disabled. 1209 */ 1210 1211 /* Do Stevens' IPV6_PKTOPTIONS. 1212 1213 Yes, guys, it is the only place in our code, where we 1214 may make it not affecting IPv4. 1215 The rest of code is protocol independent, 1216 and I do not like idea to uglify IPv4. 1217 1218 Actually, all the idea behind IPV6_PKTOPTIONS 1219 looks not very well thought. For now we latch 1220 options, received in the last packet, enqueued 1221 by tcp. Feel free to propose better solution. 1222 --ANK (980728) 1223 */ 1224 if (np->rxopt.all) 1225 opt_skb = skb_clone(skb, sk_gfp_mask(sk, GFP_ATOMIC)); 1226 1227 if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */ 1228 struct dst_entry *dst = sk->sk_rx_dst; 1229 1230 sock_rps_save_rxhash(sk, skb); 1231 sk_mark_napi_id(sk, skb); 1232 if (dst) { 1233 if (inet_sk(sk)->rx_dst_ifindex != skb->skb_iif || 1234 dst->ops->check(dst, np->rx_dst_cookie) == NULL) { 1235 dst_release(dst); 1236 sk->sk_rx_dst = NULL; 1237 } 1238 } 1239 1240 tcp_rcv_established(sk, skb, tcp_hdr(skb), skb->len); 1241 if (opt_skb) 1242 goto ipv6_pktoptions; 1243 return 0; 1244 } 1245 1246 if (tcp_checksum_complete(skb)) 1247 goto csum_err; 1248 1249 if (sk->sk_state == TCP_LISTEN) { 1250 struct sock *nsk = tcp_v6_cookie_check(sk, skb); 1251 1252 if (!nsk) 1253 goto discard; 1254 1255 if (nsk != sk) { 1256 sock_rps_save_rxhash(nsk, skb); 1257 sk_mark_napi_id(nsk, skb); 1258 if (tcp_child_process(sk, nsk, skb)) 1259 goto reset; 1260 if (opt_skb) 1261 __kfree_skb(opt_skb); 1262 return 0; 1263 } 1264 } else 1265 sock_rps_save_rxhash(sk, skb); 1266 1267 if (tcp_rcv_state_process(sk, skb)) 1268 goto reset; 1269 if (opt_skb) 1270 goto ipv6_pktoptions; 1271 return 0; 1272 1273 reset: 1274 tcp_v6_send_reset(sk, skb); 1275 discard: 1276 if (opt_skb) 1277 __kfree_skb(opt_skb); 1278 kfree_skb(skb); 1279 return 0; 1280 csum_err: 1281 TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_CSUMERRORS); 1282 TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_INERRS); 1283 goto discard; 1284 1285 1286 ipv6_pktoptions: 1287 /* Do you ask, what is it? 1288 1289 1. skb was enqueued by tcp. 1290 2. skb is added to tail of read queue, rather than out of order. 1291 3. socket is not in passive state. 1292 4. Finally, it really contains options, which user wants to receive. 1293 */ 1294 tp = tcp_sk(sk); 1295 if (TCP_SKB_CB(opt_skb)->end_seq == tp->rcv_nxt && 1296 !((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))) { 1297 if (np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo) 1298 np->mcast_oif = tcp_v6_iif(opt_skb); 1299 if (np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) 1300 np->mcast_hops = ipv6_hdr(opt_skb)->hop_limit; 1301 if (np->rxopt.bits.rxflow || np->rxopt.bits.rxtclass) 1302 np->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(opt_skb)); 1303 if (np->repflow) 1304 np->flow_label = ip6_flowlabel(ipv6_hdr(opt_skb)); 1305 if (ipv6_opt_accepted(sk, opt_skb, &TCP_SKB_CB(opt_skb)->header.h6)) { 1306 skb_set_owner_r(opt_skb, sk); 1307 opt_skb = xchg(&np->pktoptions, opt_skb); 1308 } else { 1309 __kfree_skb(opt_skb); 1310 opt_skb = xchg(&np->pktoptions, NULL); 1311 } 1312 } 1313 1314 kfree_skb(opt_skb); 1315 return 0; 1316 } 1317 1318 static void tcp_v6_fill_cb(struct sk_buff *skb, const struct ipv6hdr *hdr, 1319 const struct tcphdr *th) 1320 { 1321 /* This is tricky: we move IP6CB at its correct location into 1322 * TCP_SKB_CB(). It must be done after xfrm6_policy_check(), because 1323 * _decode_session6() uses IP6CB(). 1324 * barrier() makes sure compiler won't play aliasing games. 1325 */ 1326 memmove(&TCP_SKB_CB(skb)->header.h6, IP6CB(skb), 1327 sizeof(struct inet6_skb_parm)); 1328 barrier(); 1329 1330 TCP_SKB_CB(skb)->seq = ntohl(th->seq); 1331 TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin + 1332 skb->len - th->doff*4); 1333 TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq); 1334 TCP_SKB_CB(skb)->tcp_flags = tcp_flag_byte(th); 1335 TCP_SKB_CB(skb)->tcp_tw_isn = 0; 1336 TCP_SKB_CB(skb)->ip_dsfield = ipv6_get_dsfield(hdr); 1337 TCP_SKB_CB(skb)->sacked = 0; 1338 } 1339 1340 static void tcp_v6_restore_cb(struct sk_buff *skb) 1341 { 1342 /* We need to move header back to the beginning if xfrm6_policy_check() 1343 * and tcp_v6_fill_cb() are going to be called again. 1344 */ 1345 memmove(IP6CB(skb), &TCP_SKB_CB(skb)->header.h6, 1346 sizeof(struct inet6_skb_parm)); 1347 } 1348 1349 static int tcp_v6_rcv(struct sk_buff *skb) 1350 { 1351 const struct tcphdr *th; 1352 const struct ipv6hdr *hdr; 1353 struct sock *sk; 1354 int ret; 1355 struct net *net = dev_net(skb->dev); 1356 1357 if (skb->pkt_type != PACKET_HOST) 1358 goto discard_it; 1359 1360 /* 1361 * Count it even if it's bad. 1362 */ 1363 TCP_INC_STATS_BH(net, TCP_MIB_INSEGS); 1364 1365 if (!pskb_may_pull(skb, sizeof(struct tcphdr))) 1366 goto discard_it; 1367 1368 th = tcp_hdr(skb); 1369 1370 if (th->doff < sizeof(struct tcphdr)/4) 1371 goto bad_packet; 1372 if (!pskb_may_pull(skb, th->doff*4)) 1373 goto discard_it; 1374 1375 if (skb_checksum_init(skb, IPPROTO_TCP, ip6_compute_pseudo)) 1376 goto csum_error; 1377 1378 th = tcp_hdr(skb); 1379 hdr = ipv6_hdr(skb); 1380 1381 lookup: 1382 sk = __inet6_lookup_skb(&tcp_hashinfo, skb, th->source, th->dest, 1383 inet6_iif(skb)); 1384 if (!sk) 1385 goto no_tcp_socket; 1386 1387 process: 1388 if (sk->sk_state == TCP_TIME_WAIT) 1389 goto do_time_wait; 1390 1391 if (sk->sk_state == TCP_NEW_SYN_RECV) { 1392 struct request_sock *req = inet_reqsk(sk); 1393 struct sock *nsk; 1394 1395 sk = req->rsk_listener; 1396 tcp_v6_fill_cb(skb, hdr, th); 1397 if (tcp_v6_inbound_md5_hash(sk, skb)) { 1398 reqsk_put(req); 1399 goto discard_it; 1400 } 1401 if (unlikely(sk->sk_state != TCP_LISTEN)) { 1402 inet_csk_reqsk_queue_drop_and_put(sk, req); 1403 goto lookup; 1404 } 1405 sock_hold(sk); 1406 nsk = tcp_check_req(sk, skb, req, false); 1407 if (!nsk) { 1408 reqsk_put(req); 1409 goto discard_and_relse; 1410 } 1411 if (nsk == sk) { 1412 reqsk_put(req); 1413 tcp_v6_restore_cb(skb); 1414 } else if (tcp_child_process(sk, nsk, skb)) { 1415 tcp_v6_send_reset(nsk, skb); 1416 goto discard_and_relse; 1417 } else { 1418 sock_put(sk); 1419 return 0; 1420 } 1421 } 1422 if (hdr->hop_limit < inet6_sk(sk)->min_hopcount) { 1423 NET_INC_STATS_BH(net, LINUX_MIB_TCPMINTTLDROP); 1424 goto discard_and_relse; 1425 } 1426 1427 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) 1428 goto discard_and_relse; 1429 1430 tcp_v6_fill_cb(skb, hdr, th); 1431 1432 if (tcp_v6_inbound_md5_hash(sk, skb)) 1433 goto discard_and_relse; 1434 1435 if (sk_filter(sk, skb)) 1436 goto discard_and_relse; 1437 1438 skb->dev = NULL; 1439 1440 if (sk->sk_state == TCP_LISTEN) { 1441 ret = tcp_v6_do_rcv(sk, skb); 1442 goto put_and_return; 1443 } 1444 1445 sk_incoming_cpu_update(sk); 1446 1447 bh_lock_sock_nested(sk); 1448 tcp_sk(sk)->segs_in += max_t(u16, 1, skb_shinfo(skb)->gso_segs); 1449 ret = 0; 1450 if (!sock_owned_by_user(sk)) { 1451 if (!tcp_prequeue(sk, skb)) 1452 ret = tcp_v6_do_rcv(sk, skb); 1453 } else if (unlikely(sk_add_backlog(sk, skb, 1454 sk->sk_rcvbuf + sk->sk_sndbuf))) { 1455 bh_unlock_sock(sk); 1456 NET_INC_STATS_BH(net, LINUX_MIB_TCPBACKLOGDROP); 1457 goto discard_and_relse; 1458 } 1459 bh_unlock_sock(sk); 1460 1461 put_and_return: 1462 sock_put(sk); 1463 return ret ? -1 : 0; 1464 1465 no_tcp_socket: 1466 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 1467 goto discard_it; 1468 1469 tcp_v6_fill_cb(skb, hdr, th); 1470 1471 if (tcp_checksum_complete(skb)) { 1472 csum_error: 1473 TCP_INC_STATS_BH(net, TCP_MIB_CSUMERRORS); 1474 bad_packet: 1475 TCP_INC_STATS_BH(net, TCP_MIB_INERRS); 1476 } else { 1477 tcp_v6_send_reset(NULL, skb); 1478 } 1479 1480 discard_it: 1481 kfree_skb(skb); 1482 return 0; 1483 1484 discard_and_relse: 1485 sock_put(sk); 1486 goto discard_it; 1487 1488 do_time_wait: 1489 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) { 1490 inet_twsk_put(inet_twsk(sk)); 1491 goto discard_it; 1492 } 1493 1494 tcp_v6_fill_cb(skb, hdr, th); 1495 1496 if (tcp_checksum_complete(skb)) { 1497 inet_twsk_put(inet_twsk(sk)); 1498 goto csum_error; 1499 } 1500 1501 switch (tcp_timewait_state_process(inet_twsk(sk), skb, th)) { 1502 case TCP_TW_SYN: 1503 { 1504 struct sock *sk2; 1505 1506 sk2 = inet6_lookup_listener(dev_net(skb->dev), &tcp_hashinfo, 1507 &ipv6_hdr(skb)->saddr, th->source, 1508 &ipv6_hdr(skb)->daddr, 1509 ntohs(th->dest), tcp_v6_iif(skb)); 1510 if (sk2) { 1511 struct inet_timewait_sock *tw = inet_twsk(sk); 1512 inet_twsk_deschedule_put(tw); 1513 sk = sk2; 1514 tcp_v6_restore_cb(skb); 1515 goto process; 1516 } 1517 /* Fall through to ACK */ 1518 } 1519 case TCP_TW_ACK: 1520 tcp_v6_timewait_ack(sk, skb); 1521 break; 1522 case TCP_TW_RST: 1523 tcp_v6_restore_cb(skb); 1524 tcp_v6_send_reset(sk, skb); 1525 inet_twsk_deschedule_put(inet_twsk(sk)); 1526 goto discard_it; 1527 case TCP_TW_SUCCESS: 1528 ; 1529 } 1530 goto discard_it; 1531 } 1532 1533 static void tcp_v6_early_demux(struct sk_buff *skb) 1534 { 1535 const struct ipv6hdr *hdr; 1536 const struct tcphdr *th; 1537 struct sock *sk; 1538 1539 if (skb->pkt_type != PACKET_HOST) 1540 return; 1541 1542 if (!pskb_may_pull(skb, skb_transport_offset(skb) + sizeof(struct tcphdr))) 1543 return; 1544 1545 hdr = ipv6_hdr(skb); 1546 th = tcp_hdr(skb); 1547 1548 if (th->doff < sizeof(struct tcphdr) / 4) 1549 return; 1550 1551 /* Note : We use inet6_iif() here, not tcp_v6_iif() */ 1552 sk = __inet6_lookup_established(dev_net(skb->dev), &tcp_hashinfo, 1553 &hdr->saddr, th->source, 1554 &hdr->daddr, ntohs(th->dest), 1555 inet6_iif(skb)); 1556 if (sk) { 1557 skb->sk = sk; 1558 skb->destructor = sock_edemux; 1559 if (sk_fullsock(sk)) { 1560 struct dst_entry *dst = READ_ONCE(sk->sk_rx_dst); 1561 1562 if (dst) 1563 dst = dst_check(dst, inet6_sk(sk)->rx_dst_cookie); 1564 if (dst && 1565 inet_sk(sk)->rx_dst_ifindex == skb->skb_iif) 1566 skb_dst_set_noref(skb, dst); 1567 } 1568 } 1569 } 1570 1571 static struct timewait_sock_ops tcp6_timewait_sock_ops = { 1572 .twsk_obj_size = sizeof(struct tcp6_timewait_sock), 1573 .twsk_unique = tcp_twsk_unique, 1574 .twsk_destructor = tcp_twsk_destructor, 1575 }; 1576 1577 static const struct inet_connection_sock_af_ops ipv6_specific = { 1578 .queue_xmit = inet6_csk_xmit, 1579 .send_check = tcp_v6_send_check, 1580 .rebuild_header = inet6_sk_rebuild_header, 1581 .sk_rx_dst_set = inet6_sk_rx_dst_set, 1582 .conn_request = tcp_v6_conn_request, 1583 .syn_recv_sock = tcp_v6_syn_recv_sock, 1584 .net_header_len = sizeof(struct ipv6hdr), 1585 .net_frag_header_len = sizeof(struct frag_hdr), 1586 .setsockopt = ipv6_setsockopt, 1587 .getsockopt = ipv6_getsockopt, 1588 .addr2sockaddr = inet6_csk_addr2sockaddr, 1589 .sockaddr_len = sizeof(struct sockaddr_in6), 1590 .bind_conflict = inet6_csk_bind_conflict, 1591 #ifdef CONFIG_COMPAT 1592 .compat_setsockopt = compat_ipv6_setsockopt, 1593 .compat_getsockopt = compat_ipv6_getsockopt, 1594 #endif 1595 .mtu_reduced = tcp_v6_mtu_reduced, 1596 }; 1597 1598 #ifdef CONFIG_TCP_MD5SIG 1599 static const struct tcp_sock_af_ops tcp_sock_ipv6_specific = { 1600 .md5_lookup = tcp_v6_md5_lookup, 1601 .calc_md5_hash = tcp_v6_md5_hash_skb, 1602 .md5_parse = tcp_v6_parse_md5_keys, 1603 }; 1604 #endif 1605 1606 /* 1607 * TCP over IPv4 via INET6 API 1608 */ 1609 static const struct inet_connection_sock_af_ops ipv6_mapped = { 1610 .queue_xmit = ip_queue_xmit, 1611 .send_check = tcp_v4_send_check, 1612 .rebuild_header = inet_sk_rebuild_header, 1613 .sk_rx_dst_set = inet_sk_rx_dst_set, 1614 .conn_request = tcp_v6_conn_request, 1615 .syn_recv_sock = tcp_v6_syn_recv_sock, 1616 .net_header_len = sizeof(struct iphdr), 1617 .setsockopt = ipv6_setsockopt, 1618 .getsockopt = ipv6_getsockopt, 1619 .addr2sockaddr = inet6_csk_addr2sockaddr, 1620 .sockaddr_len = sizeof(struct sockaddr_in6), 1621 .bind_conflict = inet6_csk_bind_conflict, 1622 #ifdef CONFIG_COMPAT 1623 .compat_setsockopt = compat_ipv6_setsockopt, 1624 .compat_getsockopt = compat_ipv6_getsockopt, 1625 #endif 1626 .mtu_reduced = tcp_v4_mtu_reduced, 1627 }; 1628 1629 #ifdef CONFIG_TCP_MD5SIG 1630 static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific = { 1631 .md5_lookup = tcp_v4_md5_lookup, 1632 .calc_md5_hash = tcp_v4_md5_hash_skb, 1633 .md5_parse = tcp_v6_parse_md5_keys, 1634 }; 1635 #endif 1636 1637 /* NOTE: A lot of things set to zero explicitly by call to 1638 * sk_alloc() so need not be done here. 1639 */ 1640 static int tcp_v6_init_sock(struct sock *sk) 1641 { 1642 struct inet_connection_sock *icsk = inet_csk(sk); 1643 1644 tcp_init_sock(sk); 1645 1646 icsk->icsk_af_ops = &ipv6_specific; 1647 1648 #ifdef CONFIG_TCP_MD5SIG 1649 tcp_sk(sk)->af_specific = &tcp_sock_ipv6_specific; 1650 #endif 1651 1652 return 0; 1653 } 1654 1655 static void tcp_v6_destroy_sock(struct sock *sk) 1656 { 1657 tcp_v4_destroy_sock(sk); 1658 inet6_destroy_sock(sk); 1659 } 1660 1661 #ifdef CONFIG_PROC_FS 1662 /* Proc filesystem TCPv6 sock list dumping. */ 1663 static void get_openreq6(struct seq_file *seq, 1664 const struct request_sock *req, int i) 1665 { 1666 long ttd = req->rsk_timer.expires - jiffies; 1667 const struct in6_addr *src = &inet_rsk(req)->ir_v6_loc_addr; 1668 const struct in6_addr *dest = &inet_rsk(req)->ir_v6_rmt_addr; 1669 1670 if (ttd < 0) 1671 ttd = 0; 1672 1673 seq_printf(seq, 1674 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1675 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %d %d %pK\n", 1676 i, 1677 src->s6_addr32[0], src->s6_addr32[1], 1678 src->s6_addr32[2], src->s6_addr32[3], 1679 inet_rsk(req)->ir_num, 1680 dest->s6_addr32[0], dest->s6_addr32[1], 1681 dest->s6_addr32[2], dest->s6_addr32[3], 1682 ntohs(inet_rsk(req)->ir_rmt_port), 1683 TCP_SYN_RECV, 1684 0, 0, /* could print option size, but that is af dependent. */ 1685 1, /* timers active (only the expire timer) */ 1686 jiffies_to_clock_t(ttd), 1687 req->num_timeout, 1688 from_kuid_munged(seq_user_ns(seq), 1689 sock_i_uid(req->rsk_listener)), 1690 0, /* non standard timer */ 1691 0, /* open_requests have no inode */ 1692 0, req); 1693 } 1694 1695 static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i) 1696 { 1697 const struct in6_addr *dest, *src; 1698 __u16 destp, srcp; 1699 int timer_active; 1700 unsigned long timer_expires; 1701 const struct inet_sock *inet = inet_sk(sp); 1702 const struct tcp_sock *tp = tcp_sk(sp); 1703 const struct inet_connection_sock *icsk = inet_csk(sp); 1704 const struct fastopen_queue *fastopenq = &icsk->icsk_accept_queue.fastopenq; 1705 int rx_queue; 1706 int state; 1707 1708 dest = &sp->sk_v6_daddr; 1709 src = &sp->sk_v6_rcv_saddr; 1710 destp = ntohs(inet->inet_dport); 1711 srcp = ntohs(inet->inet_sport); 1712 1713 if (icsk->icsk_pending == ICSK_TIME_RETRANS) { 1714 timer_active = 1; 1715 timer_expires = icsk->icsk_timeout; 1716 } else if (icsk->icsk_pending == ICSK_TIME_PROBE0) { 1717 timer_active = 4; 1718 timer_expires = icsk->icsk_timeout; 1719 } else if (timer_pending(&sp->sk_timer)) { 1720 timer_active = 2; 1721 timer_expires = sp->sk_timer.expires; 1722 } else { 1723 timer_active = 0; 1724 timer_expires = jiffies; 1725 } 1726 1727 state = sk_state_load(sp); 1728 if (state == TCP_LISTEN) 1729 rx_queue = sp->sk_ack_backlog; 1730 else 1731 /* Because we don't lock the socket, 1732 * we might find a transient negative value. 1733 */ 1734 rx_queue = max_t(int, tp->rcv_nxt - tp->copied_seq, 0); 1735 1736 seq_printf(seq, 1737 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1738 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %lu %lu %u %u %d\n", 1739 i, 1740 src->s6_addr32[0], src->s6_addr32[1], 1741 src->s6_addr32[2], src->s6_addr32[3], srcp, 1742 dest->s6_addr32[0], dest->s6_addr32[1], 1743 dest->s6_addr32[2], dest->s6_addr32[3], destp, 1744 state, 1745 tp->write_seq - tp->snd_una, 1746 rx_queue, 1747 timer_active, 1748 jiffies_delta_to_clock_t(timer_expires - jiffies), 1749 icsk->icsk_retransmits, 1750 from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)), 1751 icsk->icsk_probes_out, 1752 sock_i_ino(sp), 1753 atomic_read(&sp->sk_refcnt), sp, 1754 jiffies_to_clock_t(icsk->icsk_rto), 1755 jiffies_to_clock_t(icsk->icsk_ack.ato), 1756 (icsk->icsk_ack.quick << 1) | icsk->icsk_ack.pingpong, 1757 tp->snd_cwnd, 1758 state == TCP_LISTEN ? 1759 fastopenq->max_qlen : 1760 (tcp_in_initial_slowstart(tp) ? -1 : tp->snd_ssthresh) 1761 ); 1762 } 1763 1764 static void get_timewait6_sock(struct seq_file *seq, 1765 struct inet_timewait_sock *tw, int i) 1766 { 1767 long delta = tw->tw_timer.expires - jiffies; 1768 const struct in6_addr *dest, *src; 1769 __u16 destp, srcp; 1770 1771 dest = &tw->tw_v6_daddr; 1772 src = &tw->tw_v6_rcv_saddr; 1773 destp = ntohs(tw->tw_dport); 1774 srcp = ntohs(tw->tw_sport); 1775 1776 seq_printf(seq, 1777 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1778 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK\n", 1779 i, 1780 src->s6_addr32[0], src->s6_addr32[1], 1781 src->s6_addr32[2], src->s6_addr32[3], srcp, 1782 dest->s6_addr32[0], dest->s6_addr32[1], 1783 dest->s6_addr32[2], dest->s6_addr32[3], destp, 1784 tw->tw_substate, 0, 0, 1785 3, jiffies_delta_to_clock_t(delta), 0, 0, 0, 0, 1786 atomic_read(&tw->tw_refcnt), tw); 1787 } 1788 1789 static int tcp6_seq_show(struct seq_file *seq, void *v) 1790 { 1791 struct tcp_iter_state *st; 1792 struct sock *sk = v; 1793 1794 if (v == SEQ_START_TOKEN) { 1795 seq_puts(seq, 1796 " sl " 1797 "local_address " 1798 "remote_address " 1799 "st tx_queue rx_queue tr tm->when retrnsmt" 1800 " uid timeout inode\n"); 1801 goto out; 1802 } 1803 st = seq->private; 1804 1805 if (sk->sk_state == TCP_TIME_WAIT) 1806 get_timewait6_sock(seq, v, st->num); 1807 else if (sk->sk_state == TCP_NEW_SYN_RECV) 1808 get_openreq6(seq, v, st->num); 1809 else 1810 get_tcp6_sock(seq, v, st->num); 1811 out: 1812 return 0; 1813 } 1814 1815 static const struct file_operations tcp6_afinfo_seq_fops = { 1816 .owner = THIS_MODULE, 1817 .open = tcp_seq_open, 1818 .read = seq_read, 1819 .llseek = seq_lseek, 1820 .release = seq_release_net 1821 }; 1822 1823 static struct tcp_seq_afinfo tcp6_seq_afinfo = { 1824 .name = "tcp6", 1825 .family = AF_INET6, 1826 .seq_fops = &tcp6_afinfo_seq_fops, 1827 .seq_ops = { 1828 .show = tcp6_seq_show, 1829 }, 1830 }; 1831 1832 int __net_init tcp6_proc_init(struct net *net) 1833 { 1834 return tcp_proc_register(net, &tcp6_seq_afinfo); 1835 } 1836 1837 void tcp6_proc_exit(struct net *net) 1838 { 1839 tcp_proc_unregister(net, &tcp6_seq_afinfo); 1840 } 1841 #endif 1842 1843 static void tcp_v6_clear_sk(struct sock *sk, int size) 1844 { 1845 struct inet_sock *inet = inet_sk(sk); 1846 1847 /* we do not want to clear pinet6 field, because of RCU lookups */ 1848 sk_prot_clear_nulls(sk, offsetof(struct inet_sock, pinet6)); 1849 1850 size -= offsetof(struct inet_sock, pinet6) + sizeof(inet->pinet6); 1851 memset(&inet->pinet6 + 1, 0, size); 1852 } 1853 1854 struct proto tcpv6_prot = { 1855 .name = "TCPv6", 1856 .owner = THIS_MODULE, 1857 .close = tcp_close, 1858 .connect = tcp_v6_connect, 1859 .disconnect = tcp_disconnect, 1860 .accept = inet_csk_accept, 1861 .ioctl = tcp_ioctl, 1862 .init = tcp_v6_init_sock, 1863 .destroy = tcp_v6_destroy_sock, 1864 .shutdown = tcp_shutdown, 1865 .setsockopt = tcp_setsockopt, 1866 .getsockopt = tcp_getsockopt, 1867 .recvmsg = tcp_recvmsg, 1868 .sendmsg = tcp_sendmsg, 1869 .sendpage = tcp_sendpage, 1870 .backlog_rcv = tcp_v6_do_rcv, 1871 .release_cb = tcp_release_cb, 1872 .hash = inet_hash, 1873 .unhash = inet_unhash, 1874 .get_port = inet_csk_get_port, 1875 .enter_memory_pressure = tcp_enter_memory_pressure, 1876 .stream_memory_free = tcp_stream_memory_free, 1877 .sockets_allocated = &tcp_sockets_allocated, 1878 .memory_allocated = &tcp_memory_allocated, 1879 .memory_pressure = &tcp_memory_pressure, 1880 .orphan_count = &tcp_orphan_count, 1881 .sysctl_mem = sysctl_tcp_mem, 1882 .sysctl_wmem = sysctl_tcp_wmem, 1883 .sysctl_rmem = sysctl_tcp_rmem, 1884 .max_header = MAX_TCP_HEADER, 1885 .obj_size = sizeof(struct tcp6_sock), 1886 .slab_flags = SLAB_DESTROY_BY_RCU, 1887 .twsk_prot = &tcp6_timewait_sock_ops, 1888 .rsk_prot = &tcp6_request_sock_ops, 1889 .h.hashinfo = &tcp_hashinfo, 1890 .no_autobind = true, 1891 #ifdef CONFIG_COMPAT 1892 .compat_setsockopt = compat_tcp_setsockopt, 1893 .compat_getsockopt = compat_tcp_getsockopt, 1894 #endif 1895 .clear_sk = tcp_v6_clear_sk, 1896 .diag_destroy = tcp_abort, 1897 }; 1898 1899 static const struct inet6_protocol tcpv6_protocol = { 1900 .early_demux = tcp_v6_early_demux, 1901 .handler = tcp_v6_rcv, 1902 .err_handler = tcp_v6_err, 1903 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 1904 }; 1905 1906 static struct inet_protosw tcpv6_protosw = { 1907 .type = SOCK_STREAM, 1908 .protocol = IPPROTO_TCP, 1909 .prot = &tcpv6_prot, 1910 .ops = &inet6_stream_ops, 1911 .flags = INET_PROTOSW_PERMANENT | 1912 INET_PROTOSW_ICSK, 1913 }; 1914 1915 static int __net_init tcpv6_net_init(struct net *net) 1916 { 1917 return inet_ctl_sock_create(&net->ipv6.tcp_sk, PF_INET6, 1918 SOCK_RAW, IPPROTO_TCP, net); 1919 } 1920 1921 static void __net_exit tcpv6_net_exit(struct net *net) 1922 { 1923 inet_ctl_sock_destroy(net->ipv6.tcp_sk); 1924 } 1925 1926 static void __net_exit tcpv6_net_exit_batch(struct list_head *net_exit_list) 1927 { 1928 inet_twsk_purge(&tcp_hashinfo, &tcp_death_row, AF_INET6); 1929 } 1930 1931 static struct pernet_operations tcpv6_net_ops = { 1932 .init = tcpv6_net_init, 1933 .exit = tcpv6_net_exit, 1934 .exit_batch = tcpv6_net_exit_batch, 1935 }; 1936 1937 int __init tcpv6_init(void) 1938 { 1939 int ret; 1940 1941 ret = inet6_add_protocol(&tcpv6_protocol, IPPROTO_TCP); 1942 if (ret) 1943 goto out; 1944 1945 /* register inet6 protocol */ 1946 ret = inet6_register_protosw(&tcpv6_protosw); 1947 if (ret) 1948 goto out_tcpv6_protocol; 1949 1950 ret = register_pernet_subsys(&tcpv6_net_ops); 1951 if (ret) 1952 goto out_tcpv6_protosw; 1953 out: 1954 return ret; 1955 1956 out_tcpv6_protosw: 1957 inet6_unregister_protosw(&tcpv6_protosw); 1958 out_tcpv6_protocol: 1959 inet6_del_protocol(&tcpv6_protocol, IPPROTO_TCP); 1960 goto out; 1961 } 1962 1963 void tcpv6_exit(void) 1964 { 1965 unregister_pernet_subsys(&tcpv6_net_ops); 1966 inet6_unregister_protosw(&tcpv6_protosw); 1967 inet6_del_protocol(&tcpv6_protocol, IPPROTO_TCP); 1968 } 1969