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, NULL, 0, 874 &ipv6h->saddr, 875 th->source, &ipv6h->daddr, 876 ntohs(th->source), tcp_v6_iif(skb)); 877 if (!sk1) 878 return; 879 880 rcu_read_lock(); 881 key = tcp_v6_md5_do_lookup(sk1, &ipv6h->saddr); 882 if (!key) 883 goto release_sk1; 884 885 genhash = tcp_v6_md5_hash_skb(newhash, key, NULL, skb); 886 if (genhash || memcmp(hash_location, newhash, 16) != 0) 887 goto release_sk1; 888 } 889 #endif 890 891 if (th->ack) 892 seq = ntohl(th->ack_seq); 893 else 894 ack_seq = ntohl(th->seq) + th->syn + th->fin + skb->len - 895 (th->doff << 2); 896 897 oif = sk ? sk->sk_bound_dev_if : 0; 898 tcp_v6_send_response(sk, skb, seq, ack_seq, 0, 0, 0, oif, key, 1, 0, 0); 899 900 #ifdef CONFIG_TCP_MD5SIG 901 release_sk1: 902 if (sk1) { 903 rcu_read_unlock(); 904 sock_put(sk1); 905 } 906 #endif 907 } 908 909 static void tcp_v6_send_ack(const struct sock *sk, struct sk_buff *skb, u32 seq, 910 u32 ack, u32 win, u32 tsval, u32 tsecr, int oif, 911 struct tcp_md5sig_key *key, u8 tclass, 912 u32 label) 913 { 914 tcp_v6_send_response(sk, skb, seq, ack, win, tsval, tsecr, oif, key, 0, 915 tclass, label); 916 } 917 918 static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb) 919 { 920 struct inet_timewait_sock *tw = inet_twsk(sk); 921 struct tcp_timewait_sock *tcptw = tcp_twsk(sk); 922 923 tcp_v6_send_ack(sk, skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt, 924 tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale, 925 tcp_time_stamp + tcptw->tw_ts_offset, 926 tcptw->tw_ts_recent, tw->tw_bound_dev_if, tcp_twsk_md5_key(tcptw), 927 tw->tw_tclass, cpu_to_be32(tw->tw_flowlabel)); 928 929 inet_twsk_put(tw); 930 } 931 932 static void tcp_v6_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, 933 struct request_sock *req) 934 { 935 /* sk->sk_state == TCP_LISTEN -> for regular TCP_SYN_RECV 936 * sk->sk_state == TCP_SYN_RECV -> for Fast Open. 937 */ 938 tcp_v6_send_ack(sk, skb, (sk->sk_state == TCP_LISTEN) ? 939 tcp_rsk(req)->snt_isn + 1 : tcp_sk(sk)->snd_nxt, 940 tcp_rsk(req)->rcv_nxt, req->rsk_rcv_wnd, 941 tcp_time_stamp, req->ts_recent, sk->sk_bound_dev_if, 942 tcp_v6_md5_do_lookup(sk, &ipv6_hdr(skb)->daddr), 943 0, 0); 944 } 945 946 947 static struct sock *tcp_v6_cookie_check(struct sock *sk, struct sk_buff *skb) 948 { 949 #ifdef CONFIG_SYN_COOKIES 950 const struct tcphdr *th = tcp_hdr(skb); 951 952 if (!th->syn) 953 sk = cookie_v6_check(sk, skb); 954 #endif 955 return sk; 956 } 957 958 static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb) 959 { 960 if (skb->protocol == htons(ETH_P_IP)) 961 return tcp_v4_conn_request(sk, skb); 962 963 if (!ipv6_unicast_destination(skb)) 964 goto drop; 965 966 return tcp_conn_request(&tcp6_request_sock_ops, 967 &tcp_request_sock_ipv6_ops, sk, skb); 968 969 drop: 970 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS); 971 return 0; /* don't send reset */ 972 } 973 974 static struct sock *tcp_v6_syn_recv_sock(const struct sock *sk, struct sk_buff *skb, 975 struct request_sock *req, 976 struct dst_entry *dst, 977 struct request_sock *req_unhash, 978 bool *own_req) 979 { 980 struct inet_request_sock *ireq; 981 struct ipv6_pinfo *newnp; 982 const struct ipv6_pinfo *np = inet6_sk(sk); 983 struct ipv6_txoptions *opt; 984 struct tcp6_sock *newtcp6sk; 985 struct inet_sock *newinet; 986 struct tcp_sock *newtp; 987 struct sock *newsk; 988 #ifdef CONFIG_TCP_MD5SIG 989 struct tcp_md5sig_key *key; 990 #endif 991 struct flowi6 fl6; 992 993 if (skb->protocol == htons(ETH_P_IP)) { 994 /* 995 * v6 mapped 996 */ 997 998 newsk = tcp_v4_syn_recv_sock(sk, skb, req, dst, 999 req_unhash, own_req); 1000 1001 if (!newsk) 1002 return NULL; 1003 1004 newtcp6sk = (struct tcp6_sock *)newsk; 1005 inet_sk(newsk)->pinet6 = &newtcp6sk->inet6; 1006 1007 newinet = inet_sk(newsk); 1008 newnp = inet6_sk(newsk); 1009 newtp = tcp_sk(newsk); 1010 1011 memcpy(newnp, np, sizeof(struct ipv6_pinfo)); 1012 1013 newnp->saddr = newsk->sk_v6_rcv_saddr; 1014 1015 inet_csk(newsk)->icsk_af_ops = &ipv6_mapped; 1016 newsk->sk_backlog_rcv = tcp_v4_do_rcv; 1017 #ifdef CONFIG_TCP_MD5SIG 1018 newtp->af_specific = &tcp_sock_ipv6_mapped_specific; 1019 #endif 1020 1021 newnp->ipv6_ac_list = NULL; 1022 newnp->ipv6_fl_list = NULL; 1023 newnp->pktoptions = NULL; 1024 newnp->opt = NULL; 1025 newnp->mcast_oif = tcp_v6_iif(skb); 1026 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit; 1027 newnp->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(skb)); 1028 if (np->repflow) 1029 newnp->flow_label = ip6_flowlabel(ipv6_hdr(skb)); 1030 1031 /* 1032 * No need to charge this sock to the relevant IPv6 refcnt debug socks count 1033 * here, tcp_create_openreq_child now does this for us, see the comment in 1034 * that function for the gory details. -acme 1035 */ 1036 1037 /* It is tricky place. Until this moment IPv4 tcp 1038 worked with IPv6 icsk.icsk_af_ops. 1039 Sync it now. 1040 */ 1041 tcp_sync_mss(newsk, inet_csk(newsk)->icsk_pmtu_cookie); 1042 1043 return newsk; 1044 } 1045 1046 ireq = inet_rsk(req); 1047 1048 if (sk_acceptq_is_full(sk)) 1049 goto out_overflow; 1050 1051 if (!dst) { 1052 dst = inet6_csk_route_req(sk, &fl6, req, IPPROTO_TCP); 1053 if (!dst) 1054 goto out; 1055 } 1056 1057 newsk = tcp_create_openreq_child(sk, req, skb); 1058 if (!newsk) 1059 goto out_nonewsk; 1060 1061 /* 1062 * No need to charge this sock to the relevant IPv6 refcnt debug socks 1063 * count here, tcp_create_openreq_child now does this for us, see the 1064 * comment in that function for the gory details. -acme 1065 */ 1066 1067 newsk->sk_gso_type = SKB_GSO_TCPV6; 1068 ip6_dst_store(newsk, dst, NULL, NULL); 1069 inet6_sk_rx_dst_set(newsk, skb); 1070 1071 newtcp6sk = (struct tcp6_sock *)newsk; 1072 inet_sk(newsk)->pinet6 = &newtcp6sk->inet6; 1073 1074 newtp = tcp_sk(newsk); 1075 newinet = inet_sk(newsk); 1076 newnp = inet6_sk(newsk); 1077 1078 memcpy(newnp, np, sizeof(struct ipv6_pinfo)); 1079 1080 newsk->sk_v6_daddr = ireq->ir_v6_rmt_addr; 1081 newnp->saddr = ireq->ir_v6_loc_addr; 1082 newsk->sk_v6_rcv_saddr = ireq->ir_v6_loc_addr; 1083 newsk->sk_bound_dev_if = ireq->ir_iif; 1084 1085 /* Now IPv6 options... 1086 1087 First: no IPv4 options. 1088 */ 1089 newinet->inet_opt = NULL; 1090 newnp->ipv6_ac_list = NULL; 1091 newnp->ipv6_fl_list = NULL; 1092 1093 /* Clone RX bits */ 1094 newnp->rxopt.all = np->rxopt.all; 1095 1096 newnp->pktoptions = NULL; 1097 newnp->opt = NULL; 1098 newnp->mcast_oif = tcp_v6_iif(skb); 1099 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit; 1100 newnp->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(skb)); 1101 if (np->repflow) 1102 newnp->flow_label = ip6_flowlabel(ipv6_hdr(skb)); 1103 1104 /* Clone native IPv6 options from listening socket (if any) 1105 1106 Yes, keeping reference count would be much more clever, 1107 but we make one more one thing there: reattach optmem 1108 to newsk. 1109 */ 1110 opt = rcu_dereference(np->opt); 1111 if (opt) { 1112 opt = ipv6_dup_options(newsk, opt); 1113 RCU_INIT_POINTER(newnp->opt, opt); 1114 } 1115 inet_csk(newsk)->icsk_ext_hdr_len = 0; 1116 if (opt) 1117 inet_csk(newsk)->icsk_ext_hdr_len = opt->opt_nflen + 1118 opt->opt_flen; 1119 1120 tcp_ca_openreq_child(newsk, dst); 1121 1122 tcp_sync_mss(newsk, dst_mtu(dst)); 1123 newtp->advmss = dst_metric_advmss(dst); 1124 if (tcp_sk(sk)->rx_opt.user_mss && 1125 tcp_sk(sk)->rx_opt.user_mss < newtp->advmss) 1126 newtp->advmss = tcp_sk(sk)->rx_opt.user_mss; 1127 1128 tcp_initialize_rcv_mss(newsk); 1129 1130 newinet->inet_daddr = newinet->inet_saddr = LOOPBACK4_IPV6; 1131 newinet->inet_rcv_saddr = LOOPBACK4_IPV6; 1132 1133 #ifdef CONFIG_TCP_MD5SIG 1134 /* Copy over the MD5 key from the original socket */ 1135 key = tcp_v6_md5_do_lookup(sk, &newsk->sk_v6_daddr); 1136 if (key) { 1137 /* We're using one, so create a matching key 1138 * on the newsk structure. If we fail to get 1139 * memory, then we end up not copying the key 1140 * across. Shucks. 1141 */ 1142 tcp_md5_do_add(newsk, (union tcp_md5_addr *)&newsk->sk_v6_daddr, 1143 AF_INET6, key->key, key->keylen, 1144 sk_gfp_mask(sk, GFP_ATOMIC)); 1145 } 1146 #endif 1147 1148 if (__inet_inherit_port(sk, newsk) < 0) { 1149 inet_csk_prepare_forced_close(newsk); 1150 tcp_done(newsk); 1151 goto out; 1152 } 1153 *own_req = inet_ehash_nolisten(newsk, req_to_sk(req_unhash)); 1154 if (*own_req) { 1155 tcp_move_syn(newtp, req); 1156 1157 /* Clone pktoptions received with SYN, if we own the req */ 1158 if (ireq->pktopts) { 1159 newnp->pktoptions = skb_clone(ireq->pktopts, 1160 sk_gfp_mask(sk, GFP_ATOMIC)); 1161 consume_skb(ireq->pktopts); 1162 ireq->pktopts = NULL; 1163 if (newnp->pktoptions) 1164 skb_set_owner_r(newnp->pktoptions, newsk); 1165 } 1166 } 1167 1168 return newsk; 1169 1170 out_overflow: 1171 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS); 1172 out_nonewsk: 1173 dst_release(dst); 1174 out: 1175 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS); 1176 return NULL; 1177 } 1178 1179 /* The socket must have it's spinlock held when we get 1180 * here, unless it is a TCP_LISTEN socket. 1181 * 1182 * We have a potential double-lock case here, so even when 1183 * doing backlog processing we use the BH locking scheme. 1184 * This is because we cannot sleep with the original spinlock 1185 * held. 1186 */ 1187 static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) 1188 { 1189 struct ipv6_pinfo *np = inet6_sk(sk); 1190 struct tcp_sock *tp; 1191 struct sk_buff *opt_skb = NULL; 1192 1193 /* Imagine: socket is IPv6. IPv4 packet arrives, 1194 goes to IPv4 receive handler and backlogged. 1195 From backlog it always goes here. Kerboom... 1196 Fortunately, tcp_rcv_established and rcv_established 1197 handle them correctly, but it is not case with 1198 tcp_v6_hnd_req and tcp_v6_send_reset(). --ANK 1199 */ 1200 1201 if (skb->protocol == htons(ETH_P_IP)) 1202 return tcp_v4_do_rcv(sk, skb); 1203 1204 if (sk_filter(sk, skb)) 1205 goto discard; 1206 1207 /* 1208 * socket locking is here for SMP purposes as backlog rcv 1209 * is currently called with bh processing disabled. 1210 */ 1211 1212 /* Do Stevens' IPV6_PKTOPTIONS. 1213 1214 Yes, guys, it is the only place in our code, where we 1215 may make it not affecting IPv4. 1216 The rest of code is protocol independent, 1217 and I do not like idea to uglify IPv4. 1218 1219 Actually, all the idea behind IPV6_PKTOPTIONS 1220 looks not very well thought. For now we latch 1221 options, received in the last packet, enqueued 1222 by tcp. Feel free to propose better solution. 1223 --ANK (980728) 1224 */ 1225 if (np->rxopt.all) 1226 opt_skb = skb_clone(skb, sk_gfp_mask(sk, GFP_ATOMIC)); 1227 1228 if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */ 1229 struct dst_entry *dst = sk->sk_rx_dst; 1230 1231 sock_rps_save_rxhash(sk, skb); 1232 sk_mark_napi_id(sk, skb); 1233 if (dst) { 1234 if (inet_sk(sk)->rx_dst_ifindex != skb->skb_iif || 1235 dst->ops->check(dst, np->rx_dst_cookie) == NULL) { 1236 dst_release(dst); 1237 sk->sk_rx_dst = NULL; 1238 } 1239 } 1240 1241 tcp_rcv_established(sk, skb, tcp_hdr(skb), skb->len); 1242 if (opt_skb) 1243 goto ipv6_pktoptions; 1244 return 0; 1245 } 1246 1247 if (tcp_checksum_complete(skb)) 1248 goto csum_err; 1249 1250 if (sk->sk_state == TCP_LISTEN) { 1251 struct sock *nsk = tcp_v6_cookie_check(sk, skb); 1252 1253 if (!nsk) 1254 goto discard; 1255 1256 if (nsk != sk) { 1257 sock_rps_save_rxhash(nsk, skb); 1258 sk_mark_napi_id(nsk, skb); 1259 if (tcp_child_process(sk, nsk, skb)) 1260 goto reset; 1261 if (opt_skb) 1262 __kfree_skb(opt_skb); 1263 return 0; 1264 } 1265 } else 1266 sock_rps_save_rxhash(sk, skb); 1267 1268 if (tcp_rcv_state_process(sk, skb)) 1269 goto reset; 1270 if (opt_skb) 1271 goto ipv6_pktoptions; 1272 return 0; 1273 1274 reset: 1275 tcp_v6_send_reset(sk, skb); 1276 discard: 1277 if (opt_skb) 1278 __kfree_skb(opt_skb); 1279 kfree_skb(skb); 1280 return 0; 1281 csum_err: 1282 TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_CSUMERRORS); 1283 TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_INERRS); 1284 goto discard; 1285 1286 1287 ipv6_pktoptions: 1288 /* Do you ask, what is it? 1289 1290 1. skb was enqueued by tcp. 1291 2. skb is added to tail of read queue, rather than out of order. 1292 3. socket is not in passive state. 1293 4. Finally, it really contains options, which user wants to receive. 1294 */ 1295 tp = tcp_sk(sk); 1296 if (TCP_SKB_CB(opt_skb)->end_seq == tp->rcv_nxt && 1297 !((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))) { 1298 if (np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo) 1299 np->mcast_oif = tcp_v6_iif(opt_skb); 1300 if (np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) 1301 np->mcast_hops = ipv6_hdr(opt_skb)->hop_limit; 1302 if (np->rxopt.bits.rxflow || np->rxopt.bits.rxtclass) 1303 np->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(opt_skb)); 1304 if (np->repflow) 1305 np->flow_label = ip6_flowlabel(ipv6_hdr(opt_skb)); 1306 if (ipv6_opt_accepted(sk, opt_skb, &TCP_SKB_CB(opt_skb)->header.h6)) { 1307 skb_set_owner_r(opt_skb, sk); 1308 opt_skb = xchg(&np->pktoptions, opt_skb); 1309 } else { 1310 __kfree_skb(opt_skb); 1311 opt_skb = xchg(&np->pktoptions, NULL); 1312 } 1313 } 1314 1315 kfree_skb(opt_skb); 1316 return 0; 1317 } 1318 1319 static void tcp_v6_fill_cb(struct sk_buff *skb, const struct ipv6hdr *hdr, 1320 const struct tcphdr *th) 1321 { 1322 /* This is tricky: we move IP6CB at its correct location into 1323 * TCP_SKB_CB(). It must be done after xfrm6_policy_check(), because 1324 * _decode_session6() uses IP6CB(). 1325 * barrier() makes sure compiler won't play aliasing games. 1326 */ 1327 memmove(&TCP_SKB_CB(skb)->header.h6, IP6CB(skb), 1328 sizeof(struct inet6_skb_parm)); 1329 barrier(); 1330 1331 TCP_SKB_CB(skb)->seq = ntohl(th->seq); 1332 TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin + 1333 skb->len - th->doff*4); 1334 TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq); 1335 TCP_SKB_CB(skb)->tcp_flags = tcp_flag_byte(th); 1336 TCP_SKB_CB(skb)->tcp_tw_isn = 0; 1337 TCP_SKB_CB(skb)->ip_dsfield = ipv6_get_dsfield(hdr); 1338 TCP_SKB_CB(skb)->sacked = 0; 1339 } 1340 1341 static void tcp_v6_restore_cb(struct sk_buff *skb) 1342 { 1343 /* We need to move header back to the beginning if xfrm6_policy_check() 1344 * and tcp_v6_fill_cb() are going to be called again. 1345 */ 1346 memmove(IP6CB(skb), &TCP_SKB_CB(skb)->header.h6, 1347 sizeof(struct inet6_skb_parm)); 1348 } 1349 1350 static int tcp_v6_rcv(struct sk_buff *skb) 1351 { 1352 const struct tcphdr *th; 1353 const struct ipv6hdr *hdr; 1354 struct sock *sk; 1355 int ret; 1356 struct net *net = dev_net(skb->dev); 1357 1358 if (skb->pkt_type != PACKET_HOST) 1359 goto discard_it; 1360 1361 /* 1362 * Count it even if it's bad. 1363 */ 1364 TCP_INC_STATS_BH(net, TCP_MIB_INSEGS); 1365 1366 if (!pskb_may_pull(skb, sizeof(struct tcphdr))) 1367 goto discard_it; 1368 1369 th = tcp_hdr(skb); 1370 1371 if (th->doff < sizeof(struct tcphdr)/4) 1372 goto bad_packet; 1373 if (!pskb_may_pull(skb, th->doff*4)) 1374 goto discard_it; 1375 1376 if (skb_checksum_init(skb, IPPROTO_TCP, ip6_compute_pseudo)) 1377 goto csum_error; 1378 1379 th = tcp_hdr(skb); 1380 hdr = ipv6_hdr(skb); 1381 1382 lookup: 1383 sk = __inet6_lookup_skb(&tcp_hashinfo, skb, __tcp_hdrlen(th), 1384 th->source, th->dest, inet6_iif(skb)); 1385 if (!sk) 1386 goto no_tcp_socket; 1387 1388 process: 1389 if (sk->sk_state == TCP_TIME_WAIT) 1390 goto do_time_wait; 1391 1392 if (sk->sk_state == TCP_NEW_SYN_RECV) { 1393 struct request_sock *req = inet_reqsk(sk); 1394 struct sock *nsk; 1395 1396 sk = req->rsk_listener; 1397 tcp_v6_fill_cb(skb, hdr, th); 1398 if (tcp_v6_inbound_md5_hash(sk, skb)) { 1399 reqsk_put(req); 1400 goto discard_it; 1401 } 1402 if (unlikely(sk->sk_state != TCP_LISTEN)) { 1403 inet_csk_reqsk_queue_drop_and_put(sk, req); 1404 goto lookup; 1405 } 1406 sock_hold(sk); 1407 nsk = tcp_check_req(sk, skb, req, false); 1408 if (!nsk) { 1409 reqsk_put(req); 1410 goto discard_and_relse; 1411 } 1412 if (nsk == sk) { 1413 reqsk_put(req); 1414 tcp_v6_restore_cb(skb); 1415 } else if (tcp_child_process(sk, nsk, skb)) { 1416 tcp_v6_send_reset(nsk, skb); 1417 goto discard_and_relse; 1418 } else { 1419 sock_put(sk); 1420 return 0; 1421 } 1422 } 1423 if (hdr->hop_limit < inet6_sk(sk)->min_hopcount) { 1424 NET_INC_STATS_BH(net, LINUX_MIB_TCPMINTTLDROP); 1425 goto discard_and_relse; 1426 } 1427 1428 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) 1429 goto discard_and_relse; 1430 1431 tcp_v6_fill_cb(skb, hdr, th); 1432 1433 if (tcp_v6_inbound_md5_hash(sk, skb)) 1434 goto discard_and_relse; 1435 1436 if (sk_filter(sk, skb)) 1437 goto discard_and_relse; 1438 1439 skb->dev = NULL; 1440 1441 if (sk->sk_state == TCP_LISTEN) { 1442 ret = tcp_v6_do_rcv(sk, skb); 1443 goto put_and_return; 1444 } 1445 1446 sk_incoming_cpu_update(sk); 1447 1448 bh_lock_sock_nested(sk); 1449 tcp_segs_in(tcp_sk(sk), skb); 1450 ret = 0; 1451 if (!sock_owned_by_user(sk)) { 1452 if (!tcp_prequeue(sk, skb)) 1453 ret = tcp_v6_do_rcv(sk, skb); 1454 } else if (unlikely(sk_add_backlog(sk, skb, 1455 sk->sk_rcvbuf + sk->sk_sndbuf))) { 1456 bh_unlock_sock(sk); 1457 NET_INC_STATS_BH(net, LINUX_MIB_TCPBACKLOGDROP); 1458 goto discard_and_relse; 1459 } 1460 bh_unlock_sock(sk); 1461 1462 put_and_return: 1463 sock_put(sk); 1464 return ret ? -1 : 0; 1465 1466 no_tcp_socket: 1467 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 1468 goto discard_it; 1469 1470 tcp_v6_fill_cb(skb, hdr, th); 1471 1472 if (tcp_checksum_complete(skb)) { 1473 csum_error: 1474 TCP_INC_STATS_BH(net, TCP_MIB_CSUMERRORS); 1475 bad_packet: 1476 TCP_INC_STATS_BH(net, TCP_MIB_INERRS); 1477 } else { 1478 tcp_v6_send_reset(NULL, skb); 1479 } 1480 1481 discard_it: 1482 kfree_skb(skb); 1483 return 0; 1484 1485 discard_and_relse: 1486 sock_put(sk); 1487 goto discard_it; 1488 1489 do_time_wait: 1490 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) { 1491 inet_twsk_put(inet_twsk(sk)); 1492 goto discard_it; 1493 } 1494 1495 tcp_v6_fill_cb(skb, hdr, th); 1496 1497 if (tcp_checksum_complete(skb)) { 1498 inet_twsk_put(inet_twsk(sk)); 1499 goto csum_error; 1500 } 1501 1502 switch (tcp_timewait_state_process(inet_twsk(sk), skb, th)) { 1503 case TCP_TW_SYN: 1504 { 1505 struct sock *sk2; 1506 1507 sk2 = inet6_lookup_listener(dev_net(skb->dev), &tcp_hashinfo, 1508 skb, __tcp_hdrlen(th), 1509 &ipv6_hdr(skb)->saddr, th->source, 1510 &ipv6_hdr(skb)->daddr, 1511 ntohs(th->dest), tcp_v6_iif(skb)); 1512 if (sk2) { 1513 struct inet_timewait_sock *tw = inet_twsk(sk); 1514 inet_twsk_deschedule_put(tw); 1515 sk = sk2; 1516 tcp_v6_restore_cb(skb); 1517 goto process; 1518 } 1519 /* Fall through to ACK */ 1520 } 1521 case TCP_TW_ACK: 1522 tcp_v6_timewait_ack(sk, skb); 1523 break; 1524 case TCP_TW_RST: 1525 tcp_v6_restore_cb(skb); 1526 tcp_v6_send_reset(sk, skb); 1527 inet_twsk_deschedule_put(inet_twsk(sk)); 1528 goto discard_it; 1529 case TCP_TW_SUCCESS: 1530 ; 1531 } 1532 goto discard_it; 1533 } 1534 1535 static void tcp_v6_early_demux(struct sk_buff *skb) 1536 { 1537 const struct ipv6hdr *hdr; 1538 const struct tcphdr *th; 1539 struct sock *sk; 1540 1541 if (skb->pkt_type != PACKET_HOST) 1542 return; 1543 1544 if (!pskb_may_pull(skb, skb_transport_offset(skb) + sizeof(struct tcphdr))) 1545 return; 1546 1547 hdr = ipv6_hdr(skb); 1548 th = tcp_hdr(skb); 1549 1550 if (th->doff < sizeof(struct tcphdr) / 4) 1551 return; 1552 1553 /* Note : We use inet6_iif() here, not tcp_v6_iif() */ 1554 sk = __inet6_lookup_established(dev_net(skb->dev), &tcp_hashinfo, 1555 &hdr->saddr, th->source, 1556 &hdr->daddr, ntohs(th->dest), 1557 inet6_iif(skb)); 1558 if (sk) { 1559 skb->sk = sk; 1560 skb->destructor = sock_edemux; 1561 if (sk_fullsock(sk)) { 1562 struct dst_entry *dst = READ_ONCE(sk->sk_rx_dst); 1563 1564 if (dst) 1565 dst = dst_check(dst, inet6_sk(sk)->rx_dst_cookie); 1566 if (dst && 1567 inet_sk(sk)->rx_dst_ifindex == skb->skb_iif) 1568 skb_dst_set_noref(skb, dst); 1569 } 1570 } 1571 } 1572 1573 static struct timewait_sock_ops tcp6_timewait_sock_ops = { 1574 .twsk_obj_size = sizeof(struct tcp6_timewait_sock), 1575 .twsk_unique = tcp_twsk_unique, 1576 .twsk_destructor = tcp_twsk_destructor, 1577 }; 1578 1579 static const struct inet_connection_sock_af_ops ipv6_specific = { 1580 .queue_xmit = inet6_csk_xmit, 1581 .send_check = tcp_v6_send_check, 1582 .rebuild_header = inet6_sk_rebuild_header, 1583 .sk_rx_dst_set = inet6_sk_rx_dst_set, 1584 .conn_request = tcp_v6_conn_request, 1585 .syn_recv_sock = tcp_v6_syn_recv_sock, 1586 .net_header_len = sizeof(struct ipv6hdr), 1587 .net_frag_header_len = sizeof(struct frag_hdr), 1588 .setsockopt = ipv6_setsockopt, 1589 .getsockopt = ipv6_getsockopt, 1590 .addr2sockaddr = inet6_csk_addr2sockaddr, 1591 .sockaddr_len = sizeof(struct sockaddr_in6), 1592 .bind_conflict = inet6_csk_bind_conflict, 1593 #ifdef CONFIG_COMPAT 1594 .compat_setsockopt = compat_ipv6_setsockopt, 1595 .compat_getsockopt = compat_ipv6_getsockopt, 1596 #endif 1597 .mtu_reduced = tcp_v6_mtu_reduced, 1598 }; 1599 1600 #ifdef CONFIG_TCP_MD5SIG 1601 static const struct tcp_sock_af_ops tcp_sock_ipv6_specific = { 1602 .md5_lookup = tcp_v6_md5_lookup, 1603 .calc_md5_hash = tcp_v6_md5_hash_skb, 1604 .md5_parse = tcp_v6_parse_md5_keys, 1605 }; 1606 #endif 1607 1608 /* 1609 * TCP over IPv4 via INET6 API 1610 */ 1611 static const struct inet_connection_sock_af_ops ipv6_mapped = { 1612 .queue_xmit = ip_queue_xmit, 1613 .send_check = tcp_v4_send_check, 1614 .rebuild_header = inet_sk_rebuild_header, 1615 .sk_rx_dst_set = inet_sk_rx_dst_set, 1616 .conn_request = tcp_v6_conn_request, 1617 .syn_recv_sock = tcp_v6_syn_recv_sock, 1618 .net_header_len = sizeof(struct iphdr), 1619 .setsockopt = ipv6_setsockopt, 1620 .getsockopt = ipv6_getsockopt, 1621 .addr2sockaddr = inet6_csk_addr2sockaddr, 1622 .sockaddr_len = sizeof(struct sockaddr_in6), 1623 .bind_conflict = inet6_csk_bind_conflict, 1624 #ifdef CONFIG_COMPAT 1625 .compat_setsockopt = compat_ipv6_setsockopt, 1626 .compat_getsockopt = compat_ipv6_getsockopt, 1627 #endif 1628 .mtu_reduced = tcp_v4_mtu_reduced, 1629 }; 1630 1631 #ifdef CONFIG_TCP_MD5SIG 1632 static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific = { 1633 .md5_lookup = tcp_v4_md5_lookup, 1634 .calc_md5_hash = tcp_v4_md5_hash_skb, 1635 .md5_parse = tcp_v6_parse_md5_keys, 1636 }; 1637 #endif 1638 1639 /* NOTE: A lot of things set to zero explicitly by call to 1640 * sk_alloc() so need not be done here. 1641 */ 1642 static int tcp_v6_init_sock(struct sock *sk) 1643 { 1644 struct inet_connection_sock *icsk = inet_csk(sk); 1645 1646 tcp_init_sock(sk); 1647 1648 icsk->icsk_af_ops = &ipv6_specific; 1649 1650 #ifdef CONFIG_TCP_MD5SIG 1651 tcp_sk(sk)->af_specific = &tcp_sock_ipv6_specific; 1652 #endif 1653 1654 return 0; 1655 } 1656 1657 static void tcp_v6_destroy_sock(struct sock *sk) 1658 { 1659 tcp_v4_destroy_sock(sk); 1660 inet6_destroy_sock(sk); 1661 } 1662 1663 #ifdef CONFIG_PROC_FS 1664 /* Proc filesystem TCPv6 sock list dumping. */ 1665 static void get_openreq6(struct seq_file *seq, 1666 const struct request_sock *req, int i) 1667 { 1668 long ttd = req->rsk_timer.expires - jiffies; 1669 const struct in6_addr *src = &inet_rsk(req)->ir_v6_loc_addr; 1670 const struct in6_addr *dest = &inet_rsk(req)->ir_v6_rmt_addr; 1671 1672 if (ttd < 0) 1673 ttd = 0; 1674 1675 seq_printf(seq, 1676 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1677 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %d %d %pK\n", 1678 i, 1679 src->s6_addr32[0], src->s6_addr32[1], 1680 src->s6_addr32[2], src->s6_addr32[3], 1681 inet_rsk(req)->ir_num, 1682 dest->s6_addr32[0], dest->s6_addr32[1], 1683 dest->s6_addr32[2], dest->s6_addr32[3], 1684 ntohs(inet_rsk(req)->ir_rmt_port), 1685 TCP_SYN_RECV, 1686 0, 0, /* could print option size, but that is af dependent. */ 1687 1, /* timers active (only the expire timer) */ 1688 jiffies_to_clock_t(ttd), 1689 req->num_timeout, 1690 from_kuid_munged(seq_user_ns(seq), 1691 sock_i_uid(req->rsk_listener)), 1692 0, /* non standard timer */ 1693 0, /* open_requests have no inode */ 1694 0, req); 1695 } 1696 1697 static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i) 1698 { 1699 const struct in6_addr *dest, *src; 1700 __u16 destp, srcp; 1701 int timer_active; 1702 unsigned long timer_expires; 1703 const struct inet_sock *inet = inet_sk(sp); 1704 const struct tcp_sock *tp = tcp_sk(sp); 1705 const struct inet_connection_sock *icsk = inet_csk(sp); 1706 const struct fastopen_queue *fastopenq = &icsk->icsk_accept_queue.fastopenq; 1707 int rx_queue; 1708 int state; 1709 1710 dest = &sp->sk_v6_daddr; 1711 src = &sp->sk_v6_rcv_saddr; 1712 destp = ntohs(inet->inet_dport); 1713 srcp = ntohs(inet->inet_sport); 1714 1715 if (icsk->icsk_pending == ICSK_TIME_RETRANS) { 1716 timer_active = 1; 1717 timer_expires = icsk->icsk_timeout; 1718 } else if (icsk->icsk_pending == ICSK_TIME_PROBE0) { 1719 timer_active = 4; 1720 timer_expires = icsk->icsk_timeout; 1721 } else if (timer_pending(&sp->sk_timer)) { 1722 timer_active = 2; 1723 timer_expires = sp->sk_timer.expires; 1724 } else { 1725 timer_active = 0; 1726 timer_expires = jiffies; 1727 } 1728 1729 state = sk_state_load(sp); 1730 if (state == TCP_LISTEN) 1731 rx_queue = sp->sk_ack_backlog; 1732 else 1733 /* Because we don't lock the socket, 1734 * we might find a transient negative value. 1735 */ 1736 rx_queue = max_t(int, tp->rcv_nxt - tp->copied_seq, 0); 1737 1738 seq_printf(seq, 1739 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1740 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %lu %lu %u %u %d\n", 1741 i, 1742 src->s6_addr32[0], src->s6_addr32[1], 1743 src->s6_addr32[2], src->s6_addr32[3], srcp, 1744 dest->s6_addr32[0], dest->s6_addr32[1], 1745 dest->s6_addr32[2], dest->s6_addr32[3], destp, 1746 state, 1747 tp->write_seq - tp->snd_una, 1748 rx_queue, 1749 timer_active, 1750 jiffies_delta_to_clock_t(timer_expires - jiffies), 1751 icsk->icsk_retransmits, 1752 from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)), 1753 icsk->icsk_probes_out, 1754 sock_i_ino(sp), 1755 atomic_read(&sp->sk_refcnt), sp, 1756 jiffies_to_clock_t(icsk->icsk_rto), 1757 jiffies_to_clock_t(icsk->icsk_ack.ato), 1758 (icsk->icsk_ack.quick << 1) | icsk->icsk_ack.pingpong, 1759 tp->snd_cwnd, 1760 state == TCP_LISTEN ? 1761 fastopenq->max_qlen : 1762 (tcp_in_initial_slowstart(tp) ? -1 : tp->snd_ssthresh) 1763 ); 1764 } 1765 1766 static void get_timewait6_sock(struct seq_file *seq, 1767 struct inet_timewait_sock *tw, int i) 1768 { 1769 long delta = tw->tw_timer.expires - jiffies; 1770 const struct in6_addr *dest, *src; 1771 __u16 destp, srcp; 1772 1773 dest = &tw->tw_v6_daddr; 1774 src = &tw->tw_v6_rcv_saddr; 1775 destp = ntohs(tw->tw_dport); 1776 srcp = ntohs(tw->tw_sport); 1777 1778 seq_printf(seq, 1779 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1780 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK\n", 1781 i, 1782 src->s6_addr32[0], src->s6_addr32[1], 1783 src->s6_addr32[2], src->s6_addr32[3], srcp, 1784 dest->s6_addr32[0], dest->s6_addr32[1], 1785 dest->s6_addr32[2], dest->s6_addr32[3], destp, 1786 tw->tw_substate, 0, 0, 1787 3, jiffies_delta_to_clock_t(delta), 0, 0, 0, 0, 1788 atomic_read(&tw->tw_refcnt), tw); 1789 } 1790 1791 static int tcp6_seq_show(struct seq_file *seq, void *v) 1792 { 1793 struct tcp_iter_state *st; 1794 struct sock *sk = v; 1795 1796 if (v == SEQ_START_TOKEN) { 1797 seq_puts(seq, 1798 " sl " 1799 "local_address " 1800 "remote_address " 1801 "st tx_queue rx_queue tr tm->when retrnsmt" 1802 " uid timeout inode\n"); 1803 goto out; 1804 } 1805 st = seq->private; 1806 1807 if (sk->sk_state == TCP_TIME_WAIT) 1808 get_timewait6_sock(seq, v, st->num); 1809 else if (sk->sk_state == TCP_NEW_SYN_RECV) 1810 get_openreq6(seq, v, st->num); 1811 else 1812 get_tcp6_sock(seq, v, st->num); 1813 out: 1814 return 0; 1815 } 1816 1817 static const struct file_operations tcp6_afinfo_seq_fops = { 1818 .owner = THIS_MODULE, 1819 .open = tcp_seq_open, 1820 .read = seq_read, 1821 .llseek = seq_lseek, 1822 .release = seq_release_net 1823 }; 1824 1825 static struct tcp_seq_afinfo tcp6_seq_afinfo = { 1826 .name = "tcp6", 1827 .family = AF_INET6, 1828 .seq_fops = &tcp6_afinfo_seq_fops, 1829 .seq_ops = { 1830 .show = tcp6_seq_show, 1831 }, 1832 }; 1833 1834 int __net_init tcp6_proc_init(struct net *net) 1835 { 1836 return tcp_proc_register(net, &tcp6_seq_afinfo); 1837 } 1838 1839 void tcp6_proc_exit(struct net *net) 1840 { 1841 tcp_proc_unregister(net, &tcp6_seq_afinfo); 1842 } 1843 #endif 1844 1845 static void tcp_v6_clear_sk(struct sock *sk, int size) 1846 { 1847 struct inet_sock *inet = inet_sk(sk); 1848 1849 /* we do not want to clear pinet6 field, because of RCU lookups */ 1850 sk_prot_clear_nulls(sk, offsetof(struct inet_sock, pinet6)); 1851 1852 size -= offsetof(struct inet_sock, pinet6) + sizeof(inet->pinet6); 1853 memset(&inet->pinet6 + 1, 0, size); 1854 } 1855 1856 struct proto tcpv6_prot = { 1857 .name = "TCPv6", 1858 .owner = THIS_MODULE, 1859 .close = tcp_close, 1860 .connect = tcp_v6_connect, 1861 .disconnect = tcp_disconnect, 1862 .accept = inet_csk_accept, 1863 .ioctl = tcp_ioctl, 1864 .init = tcp_v6_init_sock, 1865 .destroy = tcp_v6_destroy_sock, 1866 .shutdown = tcp_shutdown, 1867 .setsockopt = tcp_setsockopt, 1868 .getsockopt = tcp_getsockopt, 1869 .recvmsg = tcp_recvmsg, 1870 .sendmsg = tcp_sendmsg, 1871 .sendpage = tcp_sendpage, 1872 .backlog_rcv = tcp_v6_do_rcv, 1873 .release_cb = tcp_release_cb, 1874 .hash = inet6_hash, 1875 .unhash = inet_unhash, 1876 .get_port = inet_csk_get_port, 1877 .enter_memory_pressure = tcp_enter_memory_pressure, 1878 .stream_memory_free = tcp_stream_memory_free, 1879 .sockets_allocated = &tcp_sockets_allocated, 1880 .memory_allocated = &tcp_memory_allocated, 1881 .memory_pressure = &tcp_memory_pressure, 1882 .orphan_count = &tcp_orphan_count, 1883 .sysctl_mem = sysctl_tcp_mem, 1884 .sysctl_wmem = sysctl_tcp_wmem, 1885 .sysctl_rmem = sysctl_tcp_rmem, 1886 .max_header = MAX_TCP_HEADER, 1887 .obj_size = sizeof(struct tcp6_sock), 1888 .slab_flags = SLAB_DESTROY_BY_RCU, 1889 .twsk_prot = &tcp6_timewait_sock_ops, 1890 .rsk_prot = &tcp6_request_sock_ops, 1891 .h.hashinfo = &tcp_hashinfo, 1892 .no_autobind = true, 1893 #ifdef CONFIG_COMPAT 1894 .compat_setsockopt = compat_tcp_setsockopt, 1895 .compat_getsockopt = compat_tcp_getsockopt, 1896 #endif 1897 .clear_sk = tcp_v6_clear_sk, 1898 .diag_destroy = tcp_abort, 1899 }; 1900 1901 static const struct inet6_protocol tcpv6_protocol = { 1902 .early_demux = tcp_v6_early_demux, 1903 .handler = tcp_v6_rcv, 1904 .err_handler = tcp_v6_err, 1905 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 1906 }; 1907 1908 static struct inet_protosw tcpv6_protosw = { 1909 .type = SOCK_STREAM, 1910 .protocol = IPPROTO_TCP, 1911 .prot = &tcpv6_prot, 1912 .ops = &inet6_stream_ops, 1913 .flags = INET_PROTOSW_PERMANENT | 1914 INET_PROTOSW_ICSK, 1915 }; 1916 1917 static int __net_init tcpv6_net_init(struct net *net) 1918 { 1919 return inet_ctl_sock_create(&net->ipv6.tcp_sk, PF_INET6, 1920 SOCK_RAW, IPPROTO_TCP, net); 1921 } 1922 1923 static void __net_exit tcpv6_net_exit(struct net *net) 1924 { 1925 inet_ctl_sock_destroy(net->ipv6.tcp_sk); 1926 } 1927 1928 static void __net_exit tcpv6_net_exit_batch(struct list_head *net_exit_list) 1929 { 1930 inet_twsk_purge(&tcp_hashinfo, &tcp_death_row, AF_INET6); 1931 } 1932 1933 static struct pernet_operations tcpv6_net_ops = { 1934 .init = tcpv6_net_init, 1935 .exit = tcpv6_net_exit, 1936 .exit_batch = tcpv6_net_exit_batch, 1937 }; 1938 1939 int __init tcpv6_init(void) 1940 { 1941 int ret; 1942 1943 ret = inet6_add_protocol(&tcpv6_protocol, IPPROTO_TCP); 1944 if (ret) 1945 goto out; 1946 1947 /* register inet6 protocol */ 1948 ret = inet6_register_protosw(&tcpv6_protosw); 1949 if (ret) 1950 goto out_tcpv6_protocol; 1951 1952 ret = register_pernet_subsys(&tcpv6_net_ops); 1953 if (ret) 1954 goto out_tcpv6_protosw; 1955 out: 1956 return ret; 1957 1958 out_tcpv6_protosw: 1959 inet6_unregister_protosw(&tcpv6_protosw); 1960 out_tcpv6_protocol: 1961 inet6_del_protocol(&tcpv6_protocol, IPPROTO_TCP); 1962 goto out; 1963 } 1964 1965 void tcpv6_exit(void) 1966 { 1967 unregister_pernet_subsys(&tcpv6_net_ops); 1968 inet6_unregister_protosw(&tcpv6_protosw); 1969 inet6_del_protocol(&tcpv6_protocol, IPPROTO_TCP); 1970 } 1971