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, lockdep_sock_is_held(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(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(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(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(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 enum tcp_synack_type synack_type) 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, synack_type); 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(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND); 653 return true; 654 } 655 656 if (!hash_expected && hash_location) { 657 NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED); 658 return true; 659 } 660 661 /* check the signature */ 662 genhash = tcp_v6_md5_hash_skb(newhash, 663 hash_expected, 664 NULL, skb); 665 666 if (genhash || memcmp(hash_location, newhash, 16) != 0) { 667 net_info_ratelimited("MD5 Hash %s for [%pI6c]:%u->[%pI6c]:%u\n", 668 genhash ? "failed" : "mismatch", 669 &ip6h->saddr, ntohs(th->source), 670 &ip6h->daddr, ntohs(th->dest)); 671 return true; 672 } 673 #endif 674 return false; 675 } 676 677 static void tcp_v6_init_req(struct request_sock *req, 678 const struct sock *sk_listener, 679 struct sk_buff *skb) 680 { 681 struct inet_request_sock *ireq = inet_rsk(req); 682 const struct ipv6_pinfo *np = inet6_sk(sk_listener); 683 684 ireq->ir_v6_rmt_addr = ipv6_hdr(skb)->saddr; 685 ireq->ir_v6_loc_addr = ipv6_hdr(skb)->daddr; 686 687 /* So that link locals have meaning */ 688 if (!sk_listener->sk_bound_dev_if && 689 ipv6_addr_type(&ireq->ir_v6_rmt_addr) & IPV6_ADDR_LINKLOCAL) 690 ireq->ir_iif = tcp_v6_iif(skb); 691 692 if (!TCP_SKB_CB(skb)->tcp_tw_isn && 693 (ipv6_opt_accepted(sk_listener, skb, &TCP_SKB_CB(skb)->header.h6) || 694 np->rxopt.bits.rxinfo || 695 np->rxopt.bits.rxoinfo || np->rxopt.bits.rxhlim || 696 np->rxopt.bits.rxohlim || np->repflow)) { 697 atomic_inc(&skb->users); 698 ireq->pktopts = skb; 699 } 700 } 701 702 static struct dst_entry *tcp_v6_route_req(const struct sock *sk, 703 struct flowi *fl, 704 const struct request_sock *req, 705 bool *strict) 706 { 707 if (strict) 708 *strict = true; 709 return inet6_csk_route_req(sk, &fl->u.ip6, req, IPPROTO_TCP); 710 } 711 712 struct request_sock_ops tcp6_request_sock_ops __read_mostly = { 713 .family = AF_INET6, 714 .obj_size = sizeof(struct tcp6_request_sock), 715 .rtx_syn_ack = tcp_rtx_synack, 716 .send_ack = tcp_v6_reqsk_send_ack, 717 .destructor = tcp_v6_reqsk_destructor, 718 .send_reset = tcp_v6_send_reset, 719 .syn_ack_timeout = tcp_syn_ack_timeout, 720 }; 721 722 static const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops = { 723 .mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - 724 sizeof(struct ipv6hdr), 725 #ifdef CONFIG_TCP_MD5SIG 726 .req_md5_lookup = tcp_v6_md5_lookup, 727 .calc_md5_hash = tcp_v6_md5_hash_skb, 728 #endif 729 .init_req = tcp_v6_init_req, 730 #ifdef CONFIG_SYN_COOKIES 731 .cookie_init_seq = cookie_v6_init_sequence, 732 #endif 733 .route_req = tcp_v6_route_req, 734 .init_seq = tcp_v6_init_sequence, 735 .send_synack = tcp_v6_send_synack, 736 }; 737 738 static void tcp_v6_send_response(const struct sock *sk, struct sk_buff *skb, u32 seq, 739 u32 ack, u32 win, u32 tsval, u32 tsecr, 740 int oif, struct tcp_md5sig_key *key, int rst, 741 u8 tclass, u32 label) 742 { 743 const struct tcphdr *th = tcp_hdr(skb); 744 struct tcphdr *t1; 745 struct sk_buff *buff; 746 struct flowi6 fl6; 747 struct net *net = sk ? sock_net(sk) : dev_net(skb_dst(skb)->dev); 748 struct sock *ctl_sk = net->ipv6.tcp_sk; 749 unsigned int tot_len = sizeof(struct tcphdr); 750 struct dst_entry *dst; 751 __be32 *topt; 752 753 if (tsecr) 754 tot_len += TCPOLEN_TSTAMP_ALIGNED; 755 #ifdef CONFIG_TCP_MD5SIG 756 if (key) 757 tot_len += TCPOLEN_MD5SIG_ALIGNED; 758 #endif 759 760 buff = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + tot_len, 761 GFP_ATOMIC); 762 if (!buff) 763 return; 764 765 skb_reserve(buff, MAX_HEADER + sizeof(struct ipv6hdr) + tot_len); 766 767 t1 = (struct tcphdr *) skb_push(buff, tot_len); 768 skb_reset_transport_header(buff); 769 770 /* Swap the send and the receive. */ 771 memset(t1, 0, sizeof(*t1)); 772 t1->dest = th->source; 773 t1->source = th->dest; 774 t1->doff = tot_len / 4; 775 t1->seq = htonl(seq); 776 t1->ack_seq = htonl(ack); 777 t1->ack = !rst || !th->ack; 778 t1->rst = rst; 779 t1->window = htons(win); 780 781 topt = (__be32 *)(t1 + 1); 782 783 if (tsecr) { 784 *topt++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | 785 (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP); 786 *topt++ = htonl(tsval); 787 *topt++ = htonl(tsecr); 788 } 789 790 #ifdef CONFIG_TCP_MD5SIG 791 if (key) { 792 *topt++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | 793 (TCPOPT_MD5SIG << 8) | TCPOLEN_MD5SIG); 794 tcp_v6_md5_hash_hdr((__u8 *)topt, key, 795 &ipv6_hdr(skb)->saddr, 796 &ipv6_hdr(skb)->daddr, t1); 797 } 798 #endif 799 800 memset(&fl6, 0, sizeof(fl6)); 801 fl6.daddr = ipv6_hdr(skb)->saddr; 802 fl6.saddr = ipv6_hdr(skb)->daddr; 803 fl6.flowlabel = label; 804 805 buff->ip_summed = CHECKSUM_PARTIAL; 806 buff->csum = 0; 807 808 __tcp_v6_send_check(buff, &fl6.saddr, &fl6.daddr); 809 810 fl6.flowi6_proto = IPPROTO_TCP; 811 if (rt6_need_strict(&fl6.daddr) && !oif) 812 fl6.flowi6_oif = tcp_v6_iif(skb); 813 else { 814 if (!oif && netif_index_is_l3_master(net, skb->skb_iif)) 815 oif = skb->skb_iif; 816 817 fl6.flowi6_oif = oif; 818 } 819 820 fl6.flowi6_mark = IP6_REPLY_MARK(net, skb->mark); 821 fl6.fl6_dport = t1->dest; 822 fl6.fl6_sport = t1->source; 823 security_skb_classify_flow(skb, flowi6_to_flowi(&fl6)); 824 825 /* Pass a socket to ip6_dst_lookup either it is for RST 826 * Underlying function will use this to retrieve the network 827 * namespace 828 */ 829 dst = ip6_dst_lookup_flow(ctl_sk, &fl6, NULL); 830 if (!IS_ERR(dst)) { 831 skb_dst_set(buff, dst); 832 ip6_xmit(ctl_sk, buff, &fl6, NULL, tclass); 833 TCP_INC_STATS(net, TCP_MIB_OUTSEGS); 834 if (rst) 835 TCP_INC_STATS(net, TCP_MIB_OUTRSTS); 836 return; 837 } 838 839 kfree_skb(buff); 840 } 841 842 static void tcp_v6_send_reset(const struct sock *sk, struct sk_buff *skb) 843 { 844 const struct tcphdr *th = tcp_hdr(skb); 845 u32 seq = 0, ack_seq = 0; 846 struct tcp_md5sig_key *key = NULL; 847 #ifdef CONFIG_TCP_MD5SIG 848 const __u8 *hash_location = NULL; 849 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 850 unsigned char newhash[16]; 851 int genhash; 852 struct sock *sk1 = NULL; 853 #endif 854 int oif; 855 856 if (th->rst) 857 return; 858 859 /* If sk not NULL, it means we did a successful lookup and incoming 860 * route had to be correct. prequeue might have dropped our dst. 861 */ 862 if (!sk && !ipv6_unicast_destination(skb)) 863 return; 864 865 #ifdef CONFIG_TCP_MD5SIG 866 rcu_read_lock(); 867 hash_location = tcp_parse_md5sig_option(th); 868 if (sk && sk_fullsock(sk)) { 869 key = tcp_v6_md5_do_lookup(sk, &ipv6h->saddr); 870 } else if (hash_location) { 871 /* 872 * active side is lost. Try to find listening socket through 873 * source port, and then find md5 key through listening socket. 874 * we are not loose security here: 875 * Incoming packet is checked with md5 hash with finding key, 876 * no RST generated if md5 hash doesn't match. 877 */ 878 sk1 = inet6_lookup_listener(dev_net(skb_dst(skb)->dev), 879 &tcp_hashinfo, NULL, 0, 880 &ipv6h->saddr, 881 th->source, &ipv6h->daddr, 882 ntohs(th->source), tcp_v6_iif(skb)); 883 if (!sk1) 884 goto out; 885 886 key = tcp_v6_md5_do_lookup(sk1, &ipv6h->saddr); 887 if (!key) 888 goto out; 889 890 genhash = tcp_v6_md5_hash_skb(newhash, key, NULL, skb); 891 if (genhash || memcmp(hash_location, newhash, 16) != 0) 892 goto out; 893 } 894 #endif 895 896 if (th->ack) 897 seq = ntohl(th->ack_seq); 898 else 899 ack_seq = ntohl(th->seq) + th->syn + th->fin + skb->len - 900 (th->doff << 2); 901 902 oif = sk ? sk->sk_bound_dev_if : 0; 903 tcp_v6_send_response(sk, skb, seq, ack_seq, 0, 0, 0, oif, key, 1, 0, 0); 904 905 #ifdef CONFIG_TCP_MD5SIG 906 out: 907 rcu_read_unlock(); 908 #endif 909 } 910 911 static void tcp_v6_send_ack(const struct sock *sk, struct sk_buff *skb, u32 seq, 912 u32 ack, u32 win, u32 tsval, u32 tsecr, int oif, 913 struct tcp_md5sig_key *key, u8 tclass, 914 u32 label) 915 { 916 tcp_v6_send_response(sk, skb, seq, ack, win, tsval, tsecr, oif, key, 0, 917 tclass, label); 918 } 919 920 static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb) 921 { 922 struct inet_timewait_sock *tw = inet_twsk(sk); 923 struct tcp_timewait_sock *tcptw = tcp_twsk(sk); 924 925 tcp_v6_send_ack(sk, skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt, 926 tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale, 927 tcp_time_stamp + tcptw->tw_ts_offset, 928 tcptw->tw_ts_recent, tw->tw_bound_dev_if, tcp_twsk_md5_key(tcptw), 929 tw->tw_tclass, cpu_to_be32(tw->tw_flowlabel)); 930 931 inet_twsk_put(tw); 932 } 933 934 static void tcp_v6_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, 935 struct request_sock *req) 936 { 937 /* sk->sk_state == TCP_LISTEN -> for regular TCP_SYN_RECV 938 * sk->sk_state == TCP_SYN_RECV -> for Fast Open. 939 */ 940 tcp_v6_send_ack(sk, skb, (sk->sk_state == TCP_LISTEN) ? 941 tcp_rsk(req)->snt_isn + 1 : tcp_sk(sk)->snd_nxt, 942 tcp_rsk(req)->rcv_nxt, req->rsk_rcv_wnd, 943 tcp_time_stamp, req->ts_recent, sk->sk_bound_dev_if, 944 tcp_v6_md5_do_lookup(sk, &ipv6_hdr(skb)->daddr), 945 0, 0); 946 } 947 948 949 static struct sock *tcp_v6_cookie_check(struct sock *sk, struct sk_buff *skb) 950 { 951 #ifdef CONFIG_SYN_COOKIES 952 const struct tcphdr *th = tcp_hdr(skb); 953 954 if (!th->syn) 955 sk = cookie_v6_check(sk, skb); 956 #endif 957 return sk; 958 } 959 960 static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb) 961 { 962 if (skb->protocol == htons(ETH_P_IP)) 963 return tcp_v4_conn_request(sk, skb); 964 965 if (!ipv6_unicast_destination(skb)) 966 goto drop; 967 968 return tcp_conn_request(&tcp6_request_sock_ops, 969 &tcp_request_sock_ipv6_ops, sk, skb); 970 971 drop: 972 tcp_listendrop(sk); 973 return 0; /* don't send reset */ 974 } 975 976 static struct sock *tcp_v6_syn_recv_sock(const struct sock *sk, struct sk_buff *skb, 977 struct request_sock *req, 978 struct dst_entry *dst, 979 struct request_sock *req_unhash, 980 bool *own_req) 981 { 982 struct inet_request_sock *ireq; 983 struct ipv6_pinfo *newnp; 984 const struct ipv6_pinfo *np = inet6_sk(sk); 985 struct ipv6_txoptions *opt; 986 struct tcp6_sock *newtcp6sk; 987 struct inet_sock *newinet; 988 struct tcp_sock *newtp; 989 struct sock *newsk; 990 #ifdef CONFIG_TCP_MD5SIG 991 struct tcp_md5sig_key *key; 992 #endif 993 struct flowi6 fl6; 994 995 if (skb->protocol == htons(ETH_P_IP)) { 996 /* 997 * v6 mapped 998 */ 999 1000 newsk = tcp_v4_syn_recv_sock(sk, skb, req, dst, 1001 req_unhash, own_req); 1002 1003 if (!newsk) 1004 return NULL; 1005 1006 newtcp6sk = (struct tcp6_sock *)newsk; 1007 inet_sk(newsk)->pinet6 = &newtcp6sk->inet6; 1008 1009 newinet = inet_sk(newsk); 1010 newnp = inet6_sk(newsk); 1011 newtp = tcp_sk(newsk); 1012 1013 memcpy(newnp, np, sizeof(struct ipv6_pinfo)); 1014 1015 newnp->saddr = newsk->sk_v6_rcv_saddr; 1016 1017 inet_csk(newsk)->icsk_af_ops = &ipv6_mapped; 1018 newsk->sk_backlog_rcv = tcp_v4_do_rcv; 1019 #ifdef CONFIG_TCP_MD5SIG 1020 newtp->af_specific = &tcp_sock_ipv6_mapped_specific; 1021 #endif 1022 1023 newnp->ipv6_ac_list = NULL; 1024 newnp->ipv6_fl_list = NULL; 1025 newnp->pktoptions = NULL; 1026 newnp->opt = NULL; 1027 newnp->mcast_oif = tcp_v6_iif(skb); 1028 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit; 1029 newnp->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(skb)); 1030 if (np->repflow) 1031 newnp->flow_label = ip6_flowlabel(ipv6_hdr(skb)); 1032 1033 /* 1034 * No need to charge this sock to the relevant IPv6 refcnt debug socks count 1035 * here, tcp_create_openreq_child now does this for us, see the comment in 1036 * that function for the gory details. -acme 1037 */ 1038 1039 /* It is tricky place. Until this moment IPv4 tcp 1040 worked with IPv6 icsk.icsk_af_ops. 1041 Sync it now. 1042 */ 1043 tcp_sync_mss(newsk, inet_csk(newsk)->icsk_pmtu_cookie); 1044 1045 return newsk; 1046 } 1047 1048 ireq = inet_rsk(req); 1049 1050 if (sk_acceptq_is_full(sk)) 1051 goto out_overflow; 1052 1053 if (!dst) { 1054 dst = inet6_csk_route_req(sk, &fl6, req, IPPROTO_TCP); 1055 if (!dst) 1056 goto out; 1057 } 1058 1059 newsk = tcp_create_openreq_child(sk, req, skb); 1060 if (!newsk) 1061 goto out_nonewsk; 1062 1063 /* 1064 * No need to charge this sock to the relevant IPv6 refcnt debug socks 1065 * count here, tcp_create_openreq_child now does this for us, see the 1066 * comment in that function for the gory details. -acme 1067 */ 1068 1069 newsk->sk_gso_type = SKB_GSO_TCPV6; 1070 ip6_dst_store(newsk, dst, NULL, NULL); 1071 inet6_sk_rx_dst_set(newsk, skb); 1072 1073 newtcp6sk = (struct tcp6_sock *)newsk; 1074 inet_sk(newsk)->pinet6 = &newtcp6sk->inet6; 1075 1076 newtp = tcp_sk(newsk); 1077 newinet = inet_sk(newsk); 1078 newnp = inet6_sk(newsk); 1079 1080 memcpy(newnp, np, sizeof(struct ipv6_pinfo)); 1081 1082 newsk->sk_v6_daddr = ireq->ir_v6_rmt_addr; 1083 newnp->saddr = ireq->ir_v6_loc_addr; 1084 newsk->sk_v6_rcv_saddr = ireq->ir_v6_loc_addr; 1085 newsk->sk_bound_dev_if = ireq->ir_iif; 1086 1087 /* Now IPv6 options... 1088 1089 First: no IPv4 options. 1090 */ 1091 newinet->inet_opt = NULL; 1092 newnp->ipv6_ac_list = NULL; 1093 newnp->ipv6_fl_list = NULL; 1094 1095 /* Clone RX bits */ 1096 newnp->rxopt.all = np->rxopt.all; 1097 1098 newnp->pktoptions = NULL; 1099 newnp->opt = NULL; 1100 newnp->mcast_oif = tcp_v6_iif(skb); 1101 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit; 1102 newnp->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(skb)); 1103 if (np->repflow) 1104 newnp->flow_label = ip6_flowlabel(ipv6_hdr(skb)); 1105 1106 /* Clone native IPv6 options from listening socket (if any) 1107 1108 Yes, keeping reference count would be much more clever, 1109 but we make one more one thing there: reattach optmem 1110 to newsk. 1111 */ 1112 opt = rcu_dereference(np->opt); 1113 if (opt) { 1114 opt = ipv6_dup_options(newsk, opt); 1115 RCU_INIT_POINTER(newnp->opt, opt); 1116 } 1117 inet_csk(newsk)->icsk_ext_hdr_len = 0; 1118 if (opt) 1119 inet_csk(newsk)->icsk_ext_hdr_len = opt->opt_nflen + 1120 opt->opt_flen; 1121 1122 tcp_ca_openreq_child(newsk, dst); 1123 1124 tcp_sync_mss(newsk, dst_mtu(dst)); 1125 newtp->advmss = dst_metric_advmss(dst); 1126 if (tcp_sk(sk)->rx_opt.user_mss && 1127 tcp_sk(sk)->rx_opt.user_mss < newtp->advmss) 1128 newtp->advmss = tcp_sk(sk)->rx_opt.user_mss; 1129 1130 tcp_initialize_rcv_mss(newsk); 1131 1132 newinet->inet_daddr = newinet->inet_saddr = LOOPBACK4_IPV6; 1133 newinet->inet_rcv_saddr = LOOPBACK4_IPV6; 1134 1135 #ifdef CONFIG_TCP_MD5SIG 1136 /* Copy over the MD5 key from the original socket */ 1137 key = tcp_v6_md5_do_lookup(sk, &newsk->sk_v6_daddr); 1138 if (key) { 1139 /* We're using one, so create a matching key 1140 * on the newsk structure. If we fail to get 1141 * memory, then we end up not copying the key 1142 * across. Shucks. 1143 */ 1144 tcp_md5_do_add(newsk, (union tcp_md5_addr *)&newsk->sk_v6_daddr, 1145 AF_INET6, key->key, key->keylen, 1146 sk_gfp_mask(sk, GFP_ATOMIC)); 1147 } 1148 #endif 1149 1150 if (__inet_inherit_port(sk, newsk) < 0) { 1151 inet_csk_prepare_forced_close(newsk); 1152 tcp_done(newsk); 1153 goto out; 1154 } 1155 *own_req = inet_ehash_nolisten(newsk, req_to_sk(req_unhash)); 1156 if (*own_req) { 1157 tcp_move_syn(newtp, req); 1158 1159 /* Clone pktoptions received with SYN, if we own the req */ 1160 if (ireq->pktopts) { 1161 newnp->pktoptions = skb_clone(ireq->pktopts, 1162 sk_gfp_mask(sk, GFP_ATOMIC)); 1163 consume_skb(ireq->pktopts); 1164 ireq->pktopts = NULL; 1165 if (newnp->pktoptions) 1166 skb_set_owner_r(newnp->pktoptions, newsk); 1167 } 1168 } 1169 1170 return newsk; 1171 1172 out_overflow: 1173 __NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS); 1174 out_nonewsk: 1175 dst_release(dst); 1176 out: 1177 tcp_listendrop(sk); 1178 return NULL; 1179 } 1180 1181 /* The socket must have it's spinlock held when we get 1182 * here, unless it is a TCP_LISTEN socket. 1183 * 1184 * We have a potential double-lock case here, so even when 1185 * doing backlog processing we use the BH locking scheme. 1186 * This is because we cannot sleep with the original spinlock 1187 * held. 1188 */ 1189 static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) 1190 { 1191 struct ipv6_pinfo *np = inet6_sk(sk); 1192 struct tcp_sock *tp; 1193 struct sk_buff *opt_skb = NULL; 1194 1195 /* Imagine: socket is IPv6. IPv4 packet arrives, 1196 goes to IPv4 receive handler and backlogged. 1197 From backlog it always goes here. Kerboom... 1198 Fortunately, tcp_rcv_established and rcv_established 1199 handle them correctly, but it is not case with 1200 tcp_v6_hnd_req and tcp_v6_send_reset(). --ANK 1201 */ 1202 1203 if (skb->protocol == htons(ETH_P_IP)) 1204 return tcp_v4_do_rcv(sk, skb); 1205 1206 if (sk_filter(sk, skb)) 1207 goto discard; 1208 1209 /* 1210 * socket locking is here for SMP purposes as backlog rcv 1211 * is currently called with bh processing disabled. 1212 */ 1213 1214 /* Do Stevens' IPV6_PKTOPTIONS. 1215 1216 Yes, guys, it is the only place in our code, where we 1217 may make it not affecting IPv4. 1218 The rest of code is protocol independent, 1219 and I do not like idea to uglify IPv4. 1220 1221 Actually, all the idea behind IPV6_PKTOPTIONS 1222 looks not very well thought. For now we latch 1223 options, received in the last packet, enqueued 1224 by tcp. Feel free to propose better solution. 1225 --ANK (980728) 1226 */ 1227 if (np->rxopt.all) 1228 opt_skb = skb_clone(skb, sk_gfp_mask(sk, GFP_ATOMIC)); 1229 1230 if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */ 1231 struct dst_entry *dst = sk->sk_rx_dst; 1232 1233 sock_rps_save_rxhash(sk, skb); 1234 sk_mark_napi_id(sk, skb); 1235 if (dst) { 1236 if (inet_sk(sk)->rx_dst_ifindex != skb->skb_iif || 1237 dst->ops->check(dst, np->rx_dst_cookie) == NULL) { 1238 dst_release(dst); 1239 sk->sk_rx_dst = NULL; 1240 } 1241 } 1242 1243 tcp_rcv_established(sk, skb, tcp_hdr(skb), skb->len); 1244 if (opt_skb) 1245 goto ipv6_pktoptions; 1246 return 0; 1247 } 1248 1249 if (tcp_checksum_complete(skb)) 1250 goto csum_err; 1251 1252 if (sk->sk_state == TCP_LISTEN) { 1253 struct sock *nsk = tcp_v6_cookie_check(sk, skb); 1254 1255 if (!nsk) 1256 goto discard; 1257 1258 if (nsk != sk) { 1259 sock_rps_save_rxhash(nsk, skb); 1260 sk_mark_napi_id(nsk, skb); 1261 if (tcp_child_process(sk, nsk, skb)) 1262 goto reset; 1263 if (opt_skb) 1264 __kfree_skb(opt_skb); 1265 return 0; 1266 } 1267 } else 1268 sock_rps_save_rxhash(sk, skb); 1269 1270 if (tcp_rcv_state_process(sk, skb)) 1271 goto reset; 1272 if (opt_skb) 1273 goto ipv6_pktoptions; 1274 return 0; 1275 1276 reset: 1277 tcp_v6_send_reset(sk, skb); 1278 discard: 1279 if (opt_skb) 1280 __kfree_skb(opt_skb); 1281 kfree_skb(skb); 1282 return 0; 1283 csum_err: 1284 TCP_INC_STATS(sock_net(sk), TCP_MIB_CSUMERRORS); 1285 TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS); 1286 goto discard; 1287 1288 1289 ipv6_pktoptions: 1290 /* Do you ask, what is it? 1291 1292 1. skb was enqueued by tcp. 1293 2. skb is added to tail of read queue, rather than out of order. 1294 3. socket is not in passive state. 1295 4. Finally, it really contains options, which user wants to receive. 1296 */ 1297 tp = tcp_sk(sk); 1298 if (TCP_SKB_CB(opt_skb)->end_seq == tp->rcv_nxt && 1299 !((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))) { 1300 if (np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo) 1301 np->mcast_oif = tcp_v6_iif(opt_skb); 1302 if (np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) 1303 np->mcast_hops = ipv6_hdr(opt_skb)->hop_limit; 1304 if (np->rxopt.bits.rxflow || np->rxopt.bits.rxtclass) 1305 np->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(opt_skb)); 1306 if (np->repflow) 1307 np->flow_label = ip6_flowlabel(ipv6_hdr(opt_skb)); 1308 if (ipv6_opt_accepted(sk, opt_skb, &TCP_SKB_CB(opt_skb)->header.h6)) { 1309 skb_set_owner_r(opt_skb, sk); 1310 opt_skb = xchg(&np->pktoptions, opt_skb); 1311 } else { 1312 __kfree_skb(opt_skb); 1313 opt_skb = xchg(&np->pktoptions, NULL); 1314 } 1315 } 1316 1317 kfree_skb(opt_skb); 1318 return 0; 1319 } 1320 1321 static void tcp_v6_fill_cb(struct sk_buff *skb, const struct ipv6hdr *hdr, 1322 const struct tcphdr *th) 1323 { 1324 /* This is tricky: we move IP6CB at its correct location into 1325 * TCP_SKB_CB(). It must be done after xfrm6_policy_check(), because 1326 * _decode_session6() uses IP6CB(). 1327 * barrier() makes sure compiler won't play aliasing games. 1328 */ 1329 memmove(&TCP_SKB_CB(skb)->header.h6, IP6CB(skb), 1330 sizeof(struct inet6_skb_parm)); 1331 barrier(); 1332 1333 TCP_SKB_CB(skb)->seq = ntohl(th->seq); 1334 TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin + 1335 skb->len - th->doff*4); 1336 TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq); 1337 TCP_SKB_CB(skb)->tcp_flags = tcp_flag_byte(th); 1338 TCP_SKB_CB(skb)->tcp_tw_isn = 0; 1339 TCP_SKB_CB(skb)->ip_dsfield = ipv6_get_dsfield(hdr); 1340 TCP_SKB_CB(skb)->sacked = 0; 1341 } 1342 1343 static void tcp_v6_restore_cb(struct sk_buff *skb) 1344 { 1345 /* We need to move header back to the beginning if xfrm6_policy_check() 1346 * and tcp_v6_fill_cb() are going to be called again. 1347 */ 1348 memmove(IP6CB(skb), &TCP_SKB_CB(skb)->header.h6, 1349 sizeof(struct inet6_skb_parm)); 1350 } 1351 1352 static int tcp_v6_rcv(struct sk_buff *skb) 1353 { 1354 const struct tcphdr *th; 1355 const struct ipv6hdr *hdr; 1356 bool refcounted; 1357 struct sock *sk; 1358 int ret; 1359 struct net *net = dev_net(skb->dev); 1360 1361 if (skb->pkt_type != PACKET_HOST) 1362 goto discard_it; 1363 1364 /* 1365 * Count it even if it's bad. 1366 */ 1367 __TCP_INC_STATS(net, TCP_MIB_INSEGS); 1368 1369 if (!pskb_may_pull(skb, sizeof(struct tcphdr))) 1370 goto discard_it; 1371 1372 th = (const struct tcphdr *)skb->data; 1373 1374 if (unlikely(th->doff < sizeof(struct tcphdr)/4)) 1375 goto bad_packet; 1376 if (!pskb_may_pull(skb, th->doff*4)) 1377 goto discard_it; 1378 1379 if (skb_checksum_init(skb, IPPROTO_TCP, ip6_compute_pseudo)) 1380 goto csum_error; 1381 1382 th = (const struct tcphdr *)skb->data; 1383 hdr = ipv6_hdr(skb); 1384 1385 lookup: 1386 sk = __inet6_lookup_skb(&tcp_hashinfo, skb, __tcp_hdrlen(th), 1387 th->source, th->dest, inet6_iif(skb), 1388 &refcounted); 1389 if (!sk) 1390 goto no_tcp_socket; 1391 1392 process: 1393 if (sk->sk_state == TCP_TIME_WAIT) 1394 goto do_time_wait; 1395 1396 if (sk->sk_state == TCP_NEW_SYN_RECV) { 1397 struct request_sock *req = inet_reqsk(sk); 1398 struct sock *nsk; 1399 1400 sk = req->rsk_listener; 1401 tcp_v6_fill_cb(skb, hdr, th); 1402 if (tcp_v6_inbound_md5_hash(sk, skb)) { 1403 reqsk_put(req); 1404 goto discard_it; 1405 } 1406 if (unlikely(sk->sk_state != TCP_LISTEN)) { 1407 inet_csk_reqsk_queue_drop_and_put(sk, req); 1408 goto lookup; 1409 } 1410 sock_hold(sk); 1411 refcounted = true; 1412 nsk = tcp_check_req(sk, skb, req, false); 1413 if (!nsk) { 1414 reqsk_put(req); 1415 goto discard_and_relse; 1416 } 1417 if (nsk == sk) { 1418 reqsk_put(req); 1419 tcp_v6_restore_cb(skb); 1420 } else if (tcp_child_process(sk, nsk, skb)) { 1421 tcp_v6_send_reset(nsk, skb); 1422 goto discard_and_relse; 1423 } else { 1424 sock_put(sk); 1425 return 0; 1426 } 1427 } 1428 if (hdr->hop_limit < inet6_sk(sk)->min_hopcount) { 1429 __NET_INC_STATS(net, LINUX_MIB_TCPMINTTLDROP); 1430 goto discard_and_relse; 1431 } 1432 1433 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) 1434 goto discard_and_relse; 1435 1436 tcp_v6_fill_cb(skb, hdr, th); 1437 1438 if (tcp_v6_inbound_md5_hash(sk, skb)) 1439 goto discard_and_relse; 1440 1441 if (sk_filter(sk, skb)) 1442 goto discard_and_relse; 1443 1444 skb->dev = NULL; 1445 1446 if (sk->sk_state == TCP_LISTEN) { 1447 ret = tcp_v6_do_rcv(sk, skb); 1448 goto put_and_return; 1449 } 1450 1451 sk_incoming_cpu_update(sk); 1452 1453 bh_lock_sock_nested(sk); 1454 tcp_segs_in(tcp_sk(sk), skb); 1455 ret = 0; 1456 if (!sock_owned_by_user(sk)) { 1457 if (!tcp_prequeue(sk, skb)) 1458 ret = tcp_v6_do_rcv(sk, skb); 1459 } else if (unlikely(sk_add_backlog(sk, skb, 1460 sk->sk_rcvbuf + sk->sk_sndbuf))) { 1461 bh_unlock_sock(sk); 1462 __NET_INC_STATS(net, LINUX_MIB_TCPBACKLOGDROP); 1463 goto discard_and_relse; 1464 } 1465 bh_unlock_sock(sk); 1466 1467 put_and_return: 1468 if (refcounted) 1469 sock_put(sk); 1470 return ret ? -1 : 0; 1471 1472 no_tcp_socket: 1473 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 1474 goto discard_it; 1475 1476 tcp_v6_fill_cb(skb, hdr, th); 1477 1478 if (tcp_checksum_complete(skb)) { 1479 csum_error: 1480 __TCP_INC_STATS(net, TCP_MIB_CSUMERRORS); 1481 bad_packet: 1482 __TCP_INC_STATS(net, TCP_MIB_INERRS); 1483 } else { 1484 tcp_v6_send_reset(NULL, skb); 1485 } 1486 1487 discard_it: 1488 kfree_skb(skb); 1489 return 0; 1490 1491 discard_and_relse: 1492 sk_drops_add(sk, skb); 1493 if (refcounted) 1494 sock_put(sk); 1495 goto discard_it; 1496 1497 do_time_wait: 1498 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) { 1499 inet_twsk_put(inet_twsk(sk)); 1500 goto discard_it; 1501 } 1502 1503 tcp_v6_fill_cb(skb, hdr, th); 1504 1505 if (tcp_checksum_complete(skb)) { 1506 inet_twsk_put(inet_twsk(sk)); 1507 goto csum_error; 1508 } 1509 1510 switch (tcp_timewait_state_process(inet_twsk(sk), skb, th)) { 1511 case TCP_TW_SYN: 1512 { 1513 struct sock *sk2; 1514 1515 sk2 = inet6_lookup_listener(dev_net(skb->dev), &tcp_hashinfo, 1516 skb, __tcp_hdrlen(th), 1517 &ipv6_hdr(skb)->saddr, th->source, 1518 &ipv6_hdr(skb)->daddr, 1519 ntohs(th->dest), tcp_v6_iif(skb)); 1520 if (sk2) { 1521 struct inet_timewait_sock *tw = inet_twsk(sk); 1522 inet_twsk_deschedule_put(tw); 1523 sk = sk2; 1524 tcp_v6_restore_cb(skb); 1525 refcounted = false; 1526 goto process; 1527 } 1528 /* Fall through to ACK */ 1529 } 1530 case TCP_TW_ACK: 1531 tcp_v6_timewait_ack(sk, skb); 1532 break; 1533 case TCP_TW_RST: 1534 tcp_v6_restore_cb(skb); 1535 tcp_v6_send_reset(sk, skb); 1536 inet_twsk_deschedule_put(inet_twsk(sk)); 1537 goto discard_it; 1538 case TCP_TW_SUCCESS: 1539 ; 1540 } 1541 goto discard_it; 1542 } 1543 1544 static void tcp_v6_early_demux(struct sk_buff *skb) 1545 { 1546 const struct ipv6hdr *hdr; 1547 const struct tcphdr *th; 1548 struct sock *sk; 1549 1550 if (skb->pkt_type != PACKET_HOST) 1551 return; 1552 1553 if (!pskb_may_pull(skb, skb_transport_offset(skb) + sizeof(struct tcphdr))) 1554 return; 1555 1556 hdr = ipv6_hdr(skb); 1557 th = tcp_hdr(skb); 1558 1559 if (th->doff < sizeof(struct tcphdr) / 4) 1560 return; 1561 1562 /* Note : We use inet6_iif() here, not tcp_v6_iif() */ 1563 sk = __inet6_lookup_established(dev_net(skb->dev), &tcp_hashinfo, 1564 &hdr->saddr, th->source, 1565 &hdr->daddr, ntohs(th->dest), 1566 inet6_iif(skb)); 1567 if (sk) { 1568 skb->sk = sk; 1569 skb->destructor = sock_edemux; 1570 if (sk_fullsock(sk)) { 1571 struct dst_entry *dst = READ_ONCE(sk->sk_rx_dst); 1572 1573 if (dst) 1574 dst = dst_check(dst, inet6_sk(sk)->rx_dst_cookie); 1575 if (dst && 1576 inet_sk(sk)->rx_dst_ifindex == skb->skb_iif) 1577 skb_dst_set_noref(skb, dst); 1578 } 1579 } 1580 } 1581 1582 static struct timewait_sock_ops tcp6_timewait_sock_ops = { 1583 .twsk_obj_size = sizeof(struct tcp6_timewait_sock), 1584 .twsk_unique = tcp_twsk_unique, 1585 .twsk_destructor = tcp_twsk_destructor, 1586 }; 1587 1588 static const struct inet_connection_sock_af_ops ipv6_specific = { 1589 .queue_xmit = inet6_csk_xmit, 1590 .send_check = tcp_v6_send_check, 1591 .rebuild_header = inet6_sk_rebuild_header, 1592 .sk_rx_dst_set = inet6_sk_rx_dst_set, 1593 .conn_request = tcp_v6_conn_request, 1594 .syn_recv_sock = tcp_v6_syn_recv_sock, 1595 .net_header_len = sizeof(struct ipv6hdr), 1596 .net_frag_header_len = sizeof(struct frag_hdr), 1597 .setsockopt = ipv6_setsockopt, 1598 .getsockopt = ipv6_getsockopt, 1599 .addr2sockaddr = inet6_csk_addr2sockaddr, 1600 .sockaddr_len = sizeof(struct sockaddr_in6), 1601 .bind_conflict = inet6_csk_bind_conflict, 1602 #ifdef CONFIG_COMPAT 1603 .compat_setsockopt = compat_ipv6_setsockopt, 1604 .compat_getsockopt = compat_ipv6_getsockopt, 1605 #endif 1606 .mtu_reduced = tcp_v6_mtu_reduced, 1607 }; 1608 1609 #ifdef CONFIG_TCP_MD5SIG 1610 static const struct tcp_sock_af_ops tcp_sock_ipv6_specific = { 1611 .md5_lookup = tcp_v6_md5_lookup, 1612 .calc_md5_hash = tcp_v6_md5_hash_skb, 1613 .md5_parse = tcp_v6_parse_md5_keys, 1614 }; 1615 #endif 1616 1617 /* 1618 * TCP over IPv4 via INET6 API 1619 */ 1620 static const struct inet_connection_sock_af_ops ipv6_mapped = { 1621 .queue_xmit = ip_queue_xmit, 1622 .send_check = tcp_v4_send_check, 1623 .rebuild_header = inet_sk_rebuild_header, 1624 .sk_rx_dst_set = inet_sk_rx_dst_set, 1625 .conn_request = tcp_v6_conn_request, 1626 .syn_recv_sock = tcp_v6_syn_recv_sock, 1627 .net_header_len = sizeof(struct iphdr), 1628 .setsockopt = ipv6_setsockopt, 1629 .getsockopt = ipv6_getsockopt, 1630 .addr2sockaddr = inet6_csk_addr2sockaddr, 1631 .sockaddr_len = sizeof(struct sockaddr_in6), 1632 .bind_conflict = inet6_csk_bind_conflict, 1633 #ifdef CONFIG_COMPAT 1634 .compat_setsockopt = compat_ipv6_setsockopt, 1635 .compat_getsockopt = compat_ipv6_getsockopt, 1636 #endif 1637 .mtu_reduced = tcp_v4_mtu_reduced, 1638 }; 1639 1640 #ifdef CONFIG_TCP_MD5SIG 1641 static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific = { 1642 .md5_lookup = tcp_v4_md5_lookup, 1643 .calc_md5_hash = tcp_v4_md5_hash_skb, 1644 .md5_parse = tcp_v6_parse_md5_keys, 1645 }; 1646 #endif 1647 1648 /* NOTE: A lot of things set to zero explicitly by call to 1649 * sk_alloc() so need not be done here. 1650 */ 1651 static int tcp_v6_init_sock(struct sock *sk) 1652 { 1653 struct inet_connection_sock *icsk = inet_csk(sk); 1654 1655 tcp_init_sock(sk); 1656 1657 icsk->icsk_af_ops = &ipv6_specific; 1658 1659 #ifdef CONFIG_TCP_MD5SIG 1660 tcp_sk(sk)->af_specific = &tcp_sock_ipv6_specific; 1661 #endif 1662 1663 return 0; 1664 } 1665 1666 static void tcp_v6_destroy_sock(struct sock *sk) 1667 { 1668 tcp_v4_destroy_sock(sk); 1669 inet6_destroy_sock(sk); 1670 } 1671 1672 #ifdef CONFIG_PROC_FS 1673 /* Proc filesystem TCPv6 sock list dumping. */ 1674 static void get_openreq6(struct seq_file *seq, 1675 const struct request_sock *req, int i) 1676 { 1677 long ttd = req->rsk_timer.expires - jiffies; 1678 const struct in6_addr *src = &inet_rsk(req)->ir_v6_loc_addr; 1679 const struct in6_addr *dest = &inet_rsk(req)->ir_v6_rmt_addr; 1680 1681 if (ttd < 0) 1682 ttd = 0; 1683 1684 seq_printf(seq, 1685 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1686 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %d %d %pK\n", 1687 i, 1688 src->s6_addr32[0], src->s6_addr32[1], 1689 src->s6_addr32[2], src->s6_addr32[3], 1690 inet_rsk(req)->ir_num, 1691 dest->s6_addr32[0], dest->s6_addr32[1], 1692 dest->s6_addr32[2], dest->s6_addr32[3], 1693 ntohs(inet_rsk(req)->ir_rmt_port), 1694 TCP_SYN_RECV, 1695 0, 0, /* could print option size, but that is af dependent. */ 1696 1, /* timers active (only the expire timer) */ 1697 jiffies_to_clock_t(ttd), 1698 req->num_timeout, 1699 from_kuid_munged(seq_user_ns(seq), 1700 sock_i_uid(req->rsk_listener)), 1701 0, /* non standard timer */ 1702 0, /* open_requests have no inode */ 1703 0, req); 1704 } 1705 1706 static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i) 1707 { 1708 const struct in6_addr *dest, *src; 1709 __u16 destp, srcp; 1710 int timer_active; 1711 unsigned long timer_expires; 1712 const struct inet_sock *inet = inet_sk(sp); 1713 const struct tcp_sock *tp = tcp_sk(sp); 1714 const struct inet_connection_sock *icsk = inet_csk(sp); 1715 const struct fastopen_queue *fastopenq = &icsk->icsk_accept_queue.fastopenq; 1716 int rx_queue; 1717 int state; 1718 1719 dest = &sp->sk_v6_daddr; 1720 src = &sp->sk_v6_rcv_saddr; 1721 destp = ntohs(inet->inet_dport); 1722 srcp = ntohs(inet->inet_sport); 1723 1724 if (icsk->icsk_pending == ICSK_TIME_RETRANS || 1725 icsk->icsk_pending == ICSK_TIME_EARLY_RETRANS || 1726 icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) { 1727 timer_active = 1; 1728 timer_expires = icsk->icsk_timeout; 1729 } else if (icsk->icsk_pending == ICSK_TIME_PROBE0) { 1730 timer_active = 4; 1731 timer_expires = icsk->icsk_timeout; 1732 } else if (timer_pending(&sp->sk_timer)) { 1733 timer_active = 2; 1734 timer_expires = sp->sk_timer.expires; 1735 } else { 1736 timer_active = 0; 1737 timer_expires = jiffies; 1738 } 1739 1740 state = sk_state_load(sp); 1741 if (state == TCP_LISTEN) 1742 rx_queue = sp->sk_ack_backlog; 1743 else 1744 /* Because we don't lock the socket, 1745 * we might find a transient negative value. 1746 */ 1747 rx_queue = max_t(int, tp->rcv_nxt - tp->copied_seq, 0); 1748 1749 seq_printf(seq, 1750 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1751 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %lu %lu %u %u %d\n", 1752 i, 1753 src->s6_addr32[0], src->s6_addr32[1], 1754 src->s6_addr32[2], src->s6_addr32[3], srcp, 1755 dest->s6_addr32[0], dest->s6_addr32[1], 1756 dest->s6_addr32[2], dest->s6_addr32[3], destp, 1757 state, 1758 tp->write_seq - tp->snd_una, 1759 rx_queue, 1760 timer_active, 1761 jiffies_delta_to_clock_t(timer_expires - jiffies), 1762 icsk->icsk_retransmits, 1763 from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)), 1764 icsk->icsk_probes_out, 1765 sock_i_ino(sp), 1766 atomic_read(&sp->sk_refcnt), sp, 1767 jiffies_to_clock_t(icsk->icsk_rto), 1768 jiffies_to_clock_t(icsk->icsk_ack.ato), 1769 (icsk->icsk_ack.quick << 1) | icsk->icsk_ack.pingpong, 1770 tp->snd_cwnd, 1771 state == TCP_LISTEN ? 1772 fastopenq->max_qlen : 1773 (tcp_in_initial_slowstart(tp) ? -1 : tp->snd_ssthresh) 1774 ); 1775 } 1776 1777 static void get_timewait6_sock(struct seq_file *seq, 1778 struct inet_timewait_sock *tw, int i) 1779 { 1780 long delta = tw->tw_timer.expires - jiffies; 1781 const struct in6_addr *dest, *src; 1782 __u16 destp, srcp; 1783 1784 dest = &tw->tw_v6_daddr; 1785 src = &tw->tw_v6_rcv_saddr; 1786 destp = ntohs(tw->tw_dport); 1787 srcp = ntohs(tw->tw_sport); 1788 1789 seq_printf(seq, 1790 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1791 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK\n", 1792 i, 1793 src->s6_addr32[0], src->s6_addr32[1], 1794 src->s6_addr32[2], src->s6_addr32[3], srcp, 1795 dest->s6_addr32[0], dest->s6_addr32[1], 1796 dest->s6_addr32[2], dest->s6_addr32[3], destp, 1797 tw->tw_substate, 0, 0, 1798 3, jiffies_delta_to_clock_t(delta), 0, 0, 0, 0, 1799 atomic_read(&tw->tw_refcnt), tw); 1800 } 1801 1802 static int tcp6_seq_show(struct seq_file *seq, void *v) 1803 { 1804 struct tcp_iter_state *st; 1805 struct sock *sk = v; 1806 1807 if (v == SEQ_START_TOKEN) { 1808 seq_puts(seq, 1809 " sl " 1810 "local_address " 1811 "remote_address " 1812 "st tx_queue rx_queue tr tm->when retrnsmt" 1813 " uid timeout inode\n"); 1814 goto out; 1815 } 1816 st = seq->private; 1817 1818 if (sk->sk_state == TCP_TIME_WAIT) 1819 get_timewait6_sock(seq, v, st->num); 1820 else if (sk->sk_state == TCP_NEW_SYN_RECV) 1821 get_openreq6(seq, v, st->num); 1822 else 1823 get_tcp6_sock(seq, v, st->num); 1824 out: 1825 return 0; 1826 } 1827 1828 static const struct file_operations tcp6_afinfo_seq_fops = { 1829 .owner = THIS_MODULE, 1830 .open = tcp_seq_open, 1831 .read = seq_read, 1832 .llseek = seq_lseek, 1833 .release = seq_release_net 1834 }; 1835 1836 static struct tcp_seq_afinfo tcp6_seq_afinfo = { 1837 .name = "tcp6", 1838 .family = AF_INET6, 1839 .seq_fops = &tcp6_afinfo_seq_fops, 1840 .seq_ops = { 1841 .show = tcp6_seq_show, 1842 }, 1843 }; 1844 1845 int __net_init tcp6_proc_init(struct net *net) 1846 { 1847 return tcp_proc_register(net, &tcp6_seq_afinfo); 1848 } 1849 1850 void tcp6_proc_exit(struct net *net) 1851 { 1852 tcp_proc_unregister(net, &tcp6_seq_afinfo); 1853 } 1854 #endif 1855 1856 static void tcp_v6_clear_sk(struct sock *sk, int size) 1857 { 1858 struct inet_sock *inet = inet_sk(sk); 1859 1860 /* we do not want to clear pinet6 field, because of RCU lookups */ 1861 sk_prot_clear_nulls(sk, offsetof(struct inet_sock, pinet6)); 1862 1863 size -= offsetof(struct inet_sock, pinet6) + sizeof(inet->pinet6); 1864 memset(&inet->pinet6 + 1, 0, size); 1865 } 1866 1867 struct proto tcpv6_prot = { 1868 .name = "TCPv6", 1869 .owner = THIS_MODULE, 1870 .close = tcp_close, 1871 .connect = tcp_v6_connect, 1872 .disconnect = tcp_disconnect, 1873 .accept = inet_csk_accept, 1874 .ioctl = tcp_ioctl, 1875 .init = tcp_v6_init_sock, 1876 .destroy = tcp_v6_destroy_sock, 1877 .shutdown = tcp_shutdown, 1878 .setsockopt = tcp_setsockopt, 1879 .getsockopt = tcp_getsockopt, 1880 .recvmsg = tcp_recvmsg, 1881 .sendmsg = tcp_sendmsg, 1882 .sendpage = tcp_sendpage, 1883 .backlog_rcv = tcp_v6_do_rcv, 1884 .release_cb = tcp_release_cb, 1885 .hash = inet6_hash, 1886 .unhash = inet_unhash, 1887 .get_port = inet_csk_get_port, 1888 .enter_memory_pressure = tcp_enter_memory_pressure, 1889 .stream_memory_free = tcp_stream_memory_free, 1890 .sockets_allocated = &tcp_sockets_allocated, 1891 .memory_allocated = &tcp_memory_allocated, 1892 .memory_pressure = &tcp_memory_pressure, 1893 .orphan_count = &tcp_orphan_count, 1894 .sysctl_mem = sysctl_tcp_mem, 1895 .sysctl_wmem = sysctl_tcp_wmem, 1896 .sysctl_rmem = sysctl_tcp_rmem, 1897 .max_header = MAX_TCP_HEADER, 1898 .obj_size = sizeof(struct tcp6_sock), 1899 .slab_flags = SLAB_DESTROY_BY_RCU, 1900 .twsk_prot = &tcp6_timewait_sock_ops, 1901 .rsk_prot = &tcp6_request_sock_ops, 1902 .h.hashinfo = &tcp_hashinfo, 1903 .no_autobind = true, 1904 #ifdef CONFIG_COMPAT 1905 .compat_setsockopt = compat_tcp_setsockopt, 1906 .compat_getsockopt = compat_tcp_getsockopt, 1907 #endif 1908 .clear_sk = tcp_v6_clear_sk, 1909 .diag_destroy = tcp_abort, 1910 }; 1911 1912 static const struct inet6_protocol tcpv6_protocol = { 1913 .early_demux = tcp_v6_early_demux, 1914 .handler = tcp_v6_rcv, 1915 .err_handler = tcp_v6_err, 1916 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 1917 }; 1918 1919 static struct inet_protosw tcpv6_protosw = { 1920 .type = SOCK_STREAM, 1921 .protocol = IPPROTO_TCP, 1922 .prot = &tcpv6_prot, 1923 .ops = &inet6_stream_ops, 1924 .flags = INET_PROTOSW_PERMANENT | 1925 INET_PROTOSW_ICSK, 1926 }; 1927 1928 static int __net_init tcpv6_net_init(struct net *net) 1929 { 1930 return inet_ctl_sock_create(&net->ipv6.tcp_sk, PF_INET6, 1931 SOCK_RAW, IPPROTO_TCP, net); 1932 } 1933 1934 static void __net_exit tcpv6_net_exit(struct net *net) 1935 { 1936 inet_ctl_sock_destroy(net->ipv6.tcp_sk); 1937 } 1938 1939 static void __net_exit tcpv6_net_exit_batch(struct list_head *net_exit_list) 1940 { 1941 inet_twsk_purge(&tcp_hashinfo, &tcp_death_row, AF_INET6); 1942 } 1943 1944 static struct pernet_operations tcpv6_net_ops = { 1945 .init = tcpv6_net_init, 1946 .exit = tcpv6_net_exit, 1947 .exit_batch = tcpv6_net_exit_batch, 1948 }; 1949 1950 int __init tcpv6_init(void) 1951 { 1952 int ret; 1953 1954 ret = inet6_add_protocol(&tcpv6_protocol, IPPROTO_TCP); 1955 if (ret) 1956 goto out; 1957 1958 /* register inet6 protocol */ 1959 ret = inet6_register_protosw(&tcpv6_protosw); 1960 if (ret) 1961 goto out_tcpv6_protocol; 1962 1963 ret = register_pernet_subsys(&tcpv6_net_ops); 1964 if (ret) 1965 goto out_tcpv6_protosw; 1966 out: 1967 return ret; 1968 1969 out_tcpv6_protosw: 1970 inet6_unregister_protosw(&tcpv6_protosw); 1971 out_tcpv6_protocol: 1972 inet6_del_protocol(&tcpv6_protocol, IPPROTO_TCP); 1973 goto out; 1974 } 1975 1976 void tcpv6_exit(void) 1977 { 1978 unregister_pernet_subsys(&tcpv6_net_ops); 1979 inet6_unregister_protosw(&tcpv6_protosw); 1980 inet6_del_protocol(&tcpv6_protocol, IPPROTO_TCP); 1981 } 1982