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 <linux/crypto.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 int err; 331 332 sk = __inet6_lookup_established(net, &tcp_hashinfo, 333 &hdr->daddr, th->dest, 334 &hdr->saddr, ntohs(th->source), 335 skb->dev->ifindex); 336 337 if (!sk) { 338 ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev), 339 ICMP6_MIB_INERRORS); 340 return; 341 } 342 343 if (sk->sk_state == TCP_TIME_WAIT) { 344 inet_twsk_put(inet_twsk(sk)); 345 return; 346 } 347 seq = ntohl(th->seq); 348 if (sk->sk_state == TCP_NEW_SYN_RECV) 349 return tcp_req_err(sk, seq); 350 351 bh_lock_sock(sk); 352 if (sock_owned_by_user(sk) && type != ICMPV6_PKT_TOOBIG) 353 NET_INC_STATS_BH(net, LINUX_MIB_LOCKDROPPEDICMPS); 354 355 if (sk->sk_state == TCP_CLOSE) 356 goto out; 357 358 if (ipv6_hdr(skb)->hop_limit < inet6_sk(sk)->min_hopcount) { 359 NET_INC_STATS_BH(net, LINUX_MIB_TCPMINTTLDROP); 360 goto out; 361 } 362 363 tp = tcp_sk(sk); 364 /* XXX (TFO) - tp->snd_una should be ISN (tcp_create_openreq_child() */ 365 fastopen = tp->fastopen_rsk; 366 snd_una = fastopen ? tcp_rsk(fastopen)->snt_isn : tp->snd_una; 367 if (sk->sk_state != TCP_LISTEN && 368 !between(seq, snd_una, tp->snd_nxt)) { 369 NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS); 370 goto out; 371 } 372 373 np = inet6_sk(sk); 374 375 if (type == NDISC_REDIRECT) { 376 struct dst_entry *dst = __sk_dst_check(sk, np->dst_cookie); 377 378 if (dst) 379 dst->ops->redirect(dst, sk, skb); 380 goto out; 381 } 382 383 if (type == ICMPV6_PKT_TOOBIG) { 384 /* We are not interested in TCP_LISTEN and open_requests 385 * (SYN-ACKs send out by Linux are always <576bytes so 386 * they should go through unfragmented). 387 */ 388 if (sk->sk_state == TCP_LISTEN) 389 goto out; 390 391 if (!ip6_sk_accept_pmtu(sk)) 392 goto out; 393 394 tp->mtu_info = ntohl(info); 395 if (!sock_owned_by_user(sk)) 396 tcp_v6_mtu_reduced(sk); 397 else if (!test_and_set_bit(TCP_MTU_REDUCED_DEFERRED, 398 &tp->tsq_flags)) 399 sock_hold(sk); 400 goto out; 401 } 402 403 icmpv6_err_convert(type, code, &err); 404 405 /* Might be for an request_sock */ 406 switch (sk->sk_state) { 407 case TCP_SYN_SENT: 408 case TCP_SYN_RECV: 409 /* Only in fast or simultaneous open. If a fast open socket is 410 * is already accepted it is treated as a connected one below. 411 */ 412 if (fastopen && !fastopen->sk) 413 break; 414 415 if (!sock_owned_by_user(sk)) { 416 sk->sk_err = err; 417 sk->sk_error_report(sk); /* Wake people up to see the error (see connect in sock.c) */ 418 419 tcp_done(sk); 420 } else 421 sk->sk_err_soft = err; 422 goto out; 423 } 424 425 if (!sock_owned_by_user(sk) && np->recverr) { 426 sk->sk_err = err; 427 sk->sk_error_report(sk); 428 } else 429 sk->sk_err_soft = err; 430 431 out: 432 bh_unlock_sock(sk); 433 sock_put(sk); 434 } 435 436 437 static int tcp_v6_send_synack(const struct sock *sk, struct dst_entry *dst, 438 struct flowi *fl, 439 struct request_sock *req, 440 struct tcp_fastopen_cookie *foc, 441 bool attach_req) 442 { 443 struct inet_request_sock *ireq = inet_rsk(req); 444 struct ipv6_pinfo *np = inet6_sk(sk); 445 struct flowi6 *fl6 = &fl->u.ip6; 446 struct sk_buff *skb; 447 int err = -ENOMEM; 448 449 /* First, grab a route. */ 450 if (!dst && (dst = inet6_csk_route_req(sk, fl6, req, 451 IPPROTO_TCP)) == NULL) 452 goto done; 453 454 skb = tcp_make_synack(sk, dst, req, foc, attach_req); 455 456 if (skb) { 457 __tcp_v6_send_check(skb, &ireq->ir_v6_loc_addr, 458 &ireq->ir_v6_rmt_addr); 459 460 fl6->daddr = ireq->ir_v6_rmt_addr; 461 if (np->repflow && ireq->pktopts) 462 fl6->flowlabel = ip6_flowlabel(ipv6_hdr(ireq->pktopts)); 463 464 rcu_read_lock(); 465 err = ip6_xmit(sk, skb, fl6, rcu_dereference(np->opt), 466 np->tclass); 467 rcu_read_unlock(); 468 err = net_xmit_eval(err); 469 } 470 471 done: 472 return err; 473 } 474 475 476 static void tcp_v6_reqsk_destructor(struct request_sock *req) 477 { 478 kfree_skb(inet_rsk(req)->pktopts); 479 } 480 481 #ifdef CONFIG_TCP_MD5SIG 482 static struct tcp_md5sig_key *tcp_v6_md5_do_lookup(const struct sock *sk, 483 const struct in6_addr *addr) 484 { 485 return tcp_md5_do_lookup(sk, (union tcp_md5_addr *)addr, AF_INET6); 486 } 487 488 static struct tcp_md5sig_key *tcp_v6_md5_lookup(const struct sock *sk, 489 const struct sock *addr_sk) 490 { 491 return tcp_v6_md5_do_lookup(sk, &addr_sk->sk_v6_daddr); 492 } 493 494 static int tcp_v6_parse_md5_keys(struct sock *sk, char __user *optval, 495 int optlen) 496 { 497 struct tcp_md5sig cmd; 498 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&cmd.tcpm_addr; 499 500 if (optlen < sizeof(cmd)) 501 return -EINVAL; 502 503 if (copy_from_user(&cmd, optval, sizeof(cmd))) 504 return -EFAULT; 505 506 if (sin6->sin6_family != AF_INET6) 507 return -EINVAL; 508 509 if (!cmd.tcpm_keylen) { 510 if (ipv6_addr_v4mapped(&sin6->sin6_addr)) 511 return tcp_md5_do_del(sk, (union tcp_md5_addr *)&sin6->sin6_addr.s6_addr32[3], 512 AF_INET); 513 return tcp_md5_do_del(sk, (union tcp_md5_addr *)&sin6->sin6_addr, 514 AF_INET6); 515 } 516 517 if (cmd.tcpm_keylen > TCP_MD5SIG_MAXKEYLEN) 518 return -EINVAL; 519 520 if (ipv6_addr_v4mapped(&sin6->sin6_addr)) 521 return tcp_md5_do_add(sk, (union tcp_md5_addr *)&sin6->sin6_addr.s6_addr32[3], 522 AF_INET, cmd.tcpm_key, cmd.tcpm_keylen, GFP_KERNEL); 523 524 return tcp_md5_do_add(sk, (union tcp_md5_addr *)&sin6->sin6_addr, 525 AF_INET6, cmd.tcpm_key, cmd.tcpm_keylen, GFP_KERNEL); 526 } 527 528 static int tcp_v6_md5_hash_pseudoheader(struct tcp_md5sig_pool *hp, 529 const struct in6_addr *daddr, 530 const struct in6_addr *saddr, int nbytes) 531 { 532 struct tcp6_pseudohdr *bp; 533 struct scatterlist sg; 534 535 bp = &hp->md5_blk.ip6; 536 /* 1. TCP pseudo-header (RFC2460) */ 537 bp->saddr = *saddr; 538 bp->daddr = *daddr; 539 bp->protocol = cpu_to_be32(IPPROTO_TCP); 540 bp->len = cpu_to_be32(nbytes); 541 542 sg_init_one(&sg, bp, sizeof(*bp)); 543 return crypto_hash_update(&hp->md5_desc, &sg, sizeof(*bp)); 544 } 545 546 static int tcp_v6_md5_hash_hdr(char *md5_hash, struct tcp_md5sig_key *key, 547 const struct in6_addr *daddr, struct in6_addr *saddr, 548 const struct tcphdr *th) 549 { 550 struct tcp_md5sig_pool *hp; 551 struct hash_desc *desc; 552 553 hp = tcp_get_md5sig_pool(); 554 if (!hp) 555 goto clear_hash_noput; 556 desc = &hp->md5_desc; 557 558 if (crypto_hash_init(desc)) 559 goto clear_hash; 560 if (tcp_v6_md5_hash_pseudoheader(hp, daddr, saddr, th->doff << 2)) 561 goto clear_hash; 562 if (tcp_md5_hash_header(hp, th)) 563 goto clear_hash; 564 if (tcp_md5_hash_key(hp, key)) 565 goto clear_hash; 566 if (crypto_hash_final(desc, md5_hash)) 567 goto clear_hash; 568 569 tcp_put_md5sig_pool(); 570 return 0; 571 572 clear_hash: 573 tcp_put_md5sig_pool(); 574 clear_hash_noput: 575 memset(md5_hash, 0, 16); 576 return 1; 577 } 578 579 static int tcp_v6_md5_hash_skb(char *md5_hash, 580 const struct tcp_md5sig_key *key, 581 const struct sock *sk, 582 const struct sk_buff *skb) 583 { 584 const struct in6_addr *saddr, *daddr; 585 struct tcp_md5sig_pool *hp; 586 struct hash_desc *desc; 587 const struct tcphdr *th = tcp_hdr(skb); 588 589 if (sk) { /* valid for establish/request sockets */ 590 saddr = &sk->sk_v6_rcv_saddr; 591 daddr = &sk->sk_v6_daddr; 592 } else { 593 const struct ipv6hdr *ip6h = ipv6_hdr(skb); 594 saddr = &ip6h->saddr; 595 daddr = &ip6h->daddr; 596 } 597 598 hp = tcp_get_md5sig_pool(); 599 if (!hp) 600 goto clear_hash_noput; 601 desc = &hp->md5_desc; 602 603 if (crypto_hash_init(desc)) 604 goto clear_hash; 605 606 if (tcp_v6_md5_hash_pseudoheader(hp, daddr, saddr, skb->len)) 607 goto clear_hash; 608 if (tcp_md5_hash_header(hp, th)) 609 goto clear_hash; 610 if (tcp_md5_hash_skb_data(hp, skb, th->doff << 2)) 611 goto clear_hash; 612 if (tcp_md5_hash_key(hp, key)) 613 goto clear_hash; 614 if (crypto_hash_final(desc, md5_hash)) 615 goto clear_hash; 616 617 tcp_put_md5sig_pool(); 618 return 0; 619 620 clear_hash: 621 tcp_put_md5sig_pool(); 622 clear_hash_noput: 623 memset(md5_hash, 0, 16); 624 return 1; 625 } 626 627 #endif 628 629 static bool tcp_v6_inbound_md5_hash(const struct sock *sk, 630 const struct sk_buff *skb) 631 { 632 #ifdef CONFIG_TCP_MD5SIG 633 const __u8 *hash_location = NULL; 634 struct tcp_md5sig_key *hash_expected; 635 const struct ipv6hdr *ip6h = ipv6_hdr(skb); 636 const struct tcphdr *th = tcp_hdr(skb); 637 int genhash; 638 u8 newhash[16]; 639 640 hash_expected = tcp_v6_md5_do_lookup(sk, &ip6h->saddr); 641 hash_location = tcp_parse_md5sig_option(th); 642 643 /* We've parsed the options - do we have a hash? */ 644 if (!hash_expected && !hash_location) 645 return false; 646 647 if (hash_expected && !hash_location) { 648 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND); 649 return true; 650 } 651 652 if (!hash_expected && hash_location) { 653 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED); 654 return true; 655 } 656 657 /* check the signature */ 658 genhash = tcp_v6_md5_hash_skb(newhash, 659 hash_expected, 660 NULL, skb); 661 662 if (genhash || memcmp(hash_location, newhash, 16) != 0) { 663 net_info_ratelimited("MD5 Hash %s for [%pI6c]:%u->[%pI6c]:%u\n", 664 genhash ? "failed" : "mismatch", 665 &ip6h->saddr, ntohs(th->source), 666 &ip6h->daddr, ntohs(th->dest)); 667 return true; 668 } 669 #endif 670 return false; 671 } 672 673 static void tcp_v6_init_req(struct request_sock *req, 674 const struct sock *sk_listener, 675 struct sk_buff *skb) 676 { 677 struct inet_request_sock *ireq = inet_rsk(req); 678 const struct ipv6_pinfo *np = inet6_sk(sk_listener); 679 680 ireq->ir_v6_rmt_addr = ipv6_hdr(skb)->saddr; 681 ireq->ir_v6_loc_addr = ipv6_hdr(skb)->daddr; 682 683 /* So that link locals have meaning */ 684 if (!sk_listener->sk_bound_dev_if && 685 ipv6_addr_type(&ireq->ir_v6_rmt_addr) & IPV6_ADDR_LINKLOCAL) 686 ireq->ir_iif = tcp_v6_iif(skb); 687 688 if (!TCP_SKB_CB(skb)->tcp_tw_isn && 689 (ipv6_opt_accepted(sk_listener, skb, &TCP_SKB_CB(skb)->header.h6) || 690 np->rxopt.bits.rxinfo || 691 np->rxopt.bits.rxoinfo || np->rxopt.bits.rxhlim || 692 np->rxopt.bits.rxohlim || np->repflow)) { 693 atomic_inc(&skb->users); 694 ireq->pktopts = skb; 695 } 696 } 697 698 static struct dst_entry *tcp_v6_route_req(const struct sock *sk, 699 struct flowi *fl, 700 const struct request_sock *req, 701 bool *strict) 702 { 703 if (strict) 704 *strict = true; 705 return inet6_csk_route_req(sk, &fl->u.ip6, req, IPPROTO_TCP); 706 } 707 708 struct request_sock_ops tcp6_request_sock_ops __read_mostly = { 709 .family = AF_INET6, 710 .obj_size = sizeof(struct tcp6_request_sock), 711 .rtx_syn_ack = tcp_rtx_synack, 712 .send_ack = tcp_v6_reqsk_send_ack, 713 .destructor = tcp_v6_reqsk_destructor, 714 .send_reset = tcp_v6_send_reset, 715 .syn_ack_timeout = tcp_syn_ack_timeout, 716 }; 717 718 static const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops = { 719 .mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - 720 sizeof(struct ipv6hdr), 721 #ifdef CONFIG_TCP_MD5SIG 722 .req_md5_lookup = tcp_v6_md5_lookup, 723 .calc_md5_hash = tcp_v6_md5_hash_skb, 724 #endif 725 .init_req = tcp_v6_init_req, 726 #ifdef CONFIG_SYN_COOKIES 727 .cookie_init_seq = cookie_v6_init_sequence, 728 #endif 729 .route_req = tcp_v6_route_req, 730 .init_seq = tcp_v6_init_sequence, 731 .send_synack = tcp_v6_send_synack, 732 }; 733 734 static void tcp_v6_send_response(const struct sock *sk, struct sk_buff *skb, u32 seq, 735 u32 ack, u32 win, u32 tsval, u32 tsecr, 736 int oif, struct tcp_md5sig_key *key, int rst, 737 u8 tclass, u32 label) 738 { 739 const struct tcphdr *th = tcp_hdr(skb); 740 struct tcphdr *t1; 741 struct sk_buff *buff; 742 struct flowi6 fl6; 743 struct net *net = sk ? sock_net(sk) : dev_net(skb_dst(skb)->dev); 744 struct sock *ctl_sk = net->ipv6.tcp_sk; 745 unsigned int tot_len = sizeof(struct tcphdr); 746 struct dst_entry *dst; 747 __be32 *topt; 748 749 if (tsecr) 750 tot_len += TCPOLEN_TSTAMP_ALIGNED; 751 #ifdef CONFIG_TCP_MD5SIG 752 if (key) 753 tot_len += TCPOLEN_MD5SIG_ALIGNED; 754 #endif 755 756 buff = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + tot_len, 757 GFP_ATOMIC); 758 if (!buff) 759 return; 760 761 skb_reserve(buff, MAX_HEADER + sizeof(struct ipv6hdr) + tot_len); 762 763 t1 = (struct tcphdr *) skb_push(buff, tot_len); 764 skb_reset_transport_header(buff); 765 766 /* Swap the send and the receive. */ 767 memset(t1, 0, sizeof(*t1)); 768 t1->dest = th->source; 769 t1->source = th->dest; 770 t1->doff = tot_len / 4; 771 t1->seq = htonl(seq); 772 t1->ack_seq = htonl(ack); 773 t1->ack = !rst || !th->ack; 774 t1->rst = rst; 775 t1->window = htons(win); 776 777 topt = (__be32 *)(t1 + 1); 778 779 if (tsecr) { 780 *topt++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | 781 (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP); 782 *topt++ = htonl(tsval); 783 *topt++ = htonl(tsecr); 784 } 785 786 #ifdef CONFIG_TCP_MD5SIG 787 if (key) { 788 *topt++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | 789 (TCPOPT_MD5SIG << 8) | TCPOLEN_MD5SIG); 790 tcp_v6_md5_hash_hdr((__u8 *)topt, key, 791 &ipv6_hdr(skb)->saddr, 792 &ipv6_hdr(skb)->daddr, t1); 793 } 794 #endif 795 796 memset(&fl6, 0, sizeof(fl6)); 797 fl6.daddr = ipv6_hdr(skb)->saddr; 798 fl6.saddr = ipv6_hdr(skb)->daddr; 799 fl6.flowlabel = label; 800 801 buff->ip_summed = CHECKSUM_PARTIAL; 802 buff->csum = 0; 803 804 __tcp_v6_send_check(buff, &fl6.saddr, &fl6.daddr); 805 806 fl6.flowi6_proto = IPPROTO_TCP; 807 if (rt6_need_strict(&fl6.daddr) && !oif) 808 fl6.flowi6_oif = tcp_v6_iif(skb); 809 else 810 fl6.flowi6_oif = oif; 811 fl6.flowi6_mark = IP6_REPLY_MARK(net, skb->mark); 812 fl6.fl6_dport = t1->dest; 813 fl6.fl6_sport = t1->source; 814 security_skb_classify_flow(skb, flowi6_to_flowi(&fl6)); 815 816 /* Pass a socket to ip6_dst_lookup either it is for RST 817 * Underlying function will use this to retrieve the network 818 * namespace 819 */ 820 dst = ip6_dst_lookup_flow(ctl_sk, &fl6, NULL); 821 if (!IS_ERR(dst)) { 822 skb_dst_set(buff, dst); 823 ip6_xmit(ctl_sk, buff, &fl6, NULL, tclass); 824 TCP_INC_STATS_BH(net, TCP_MIB_OUTSEGS); 825 if (rst) 826 TCP_INC_STATS_BH(net, TCP_MIB_OUTRSTS); 827 return; 828 } 829 830 kfree_skb(buff); 831 } 832 833 static void tcp_v6_send_reset(const struct sock *sk, struct sk_buff *skb) 834 { 835 const struct tcphdr *th = tcp_hdr(skb); 836 u32 seq = 0, ack_seq = 0; 837 struct tcp_md5sig_key *key = NULL; 838 #ifdef CONFIG_TCP_MD5SIG 839 const __u8 *hash_location = NULL; 840 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 841 unsigned char newhash[16]; 842 int genhash; 843 struct sock *sk1 = NULL; 844 #endif 845 int oif; 846 847 if (th->rst) 848 return; 849 850 /* If sk not NULL, it means we did a successful lookup and incoming 851 * route had to be correct. prequeue might have dropped our dst. 852 */ 853 if (!sk && !ipv6_unicast_destination(skb)) 854 return; 855 856 #ifdef CONFIG_TCP_MD5SIG 857 hash_location = tcp_parse_md5sig_option(th); 858 if (sk && sk_fullsock(sk)) { 859 key = tcp_v6_md5_do_lookup(sk, &ipv6h->saddr); 860 } else if (hash_location) { 861 /* 862 * active side is lost. Try to find listening socket through 863 * source port, and then find md5 key through listening socket. 864 * we are not loose security here: 865 * Incoming packet is checked with md5 hash with finding key, 866 * no RST generated if md5 hash doesn't match. 867 */ 868 sk1 = inet6_lookup_listener(dev_net(skb_dst(skb)->dev), 869 &tcp_hashinfo, &ipv6h->saddr, 870 th->source, &ipv6h->daddr, 871 ntohs(th->source), tcp_v6_iif(skb)); 872 if (!sk1) 873 return; 874 875 rcu_read_lock(); 876 key = tcp_v6_md5_do_lookup(sk1, &ipv6h->saddr); 877 if (!key) 878 goto release_sk1; 879 880 genhash = tcp_v6_md5_hash_skb(newhash, key, NULL, skb); 881 if (genhash || memcmp(hash_location, newhash, 16) != 0) 882 goto release_sk1; 883 } 884 #endif 885 886 if (th->ack) 887 seq = ntohl(th->ack_seq); 888 else 889 ack_seq = ntohl(th->seq) + th->syn + th->fin + skb->len - 890 (th->doff << 2); 891 892 oif = sk ? sk->sk_bound_dev_if : 0; 893 tcp_v6_send_response(sk, skb, seq, ack_seq, 0, 0, 0, oif, key, 1, 0, 0); 894 895 #ifdef CONFIG_TCP_MD5SIG 896 release_sk1: 897 if (sk1) { 898 rcu_read_unlock(); 899 sock_put(sk1); 900 } 901 #endif 902 } 903 904 static void tcp_v6_send_ack(const struct sock *sk, struct sk_buff *skb, u32 seq, 905 u32 ack, u32 win, u32 tsval, u32 tsecr, int oif, 906 struct tcp_md5sig_key *key, u8 tclass, 907 u32 label) 908 { 909 tcp_v6_send_response(sk, skb, seq, ack, win, tsval, tsecr, oif, key, 0, 910 tclass, label); 911 } 912 913 static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb) 914 { 915 struct inet_timewait_sock *tw = inet_twsk(sk); 916 struct tcp_timewait_sock *tcptw = tcp_twsk(sk); 917 918 tcp_v6_send_ack(sk, skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt, 919 tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale, 920 tcp_time_stamp + tcptw->tw_ts_offset, 921 tcptw->tw_ts_recent, tw->tw_bound_dev_if, tcp_twsk_md5_key(tcptw), 922 tw->tw_tclass, cpu_to_be32(tw->tw_flowlabel)); 923 924 inet_twsk_put(tw); 925 } 926 927 static void tcp_v6_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, 928 struct request_sock *req) 929 { 930 /* sk->sk_state == TCP_LISTEN -> for regular TCP_SYN_RECV 931 * sk->sk_state == TCP_SYN_RECV -> for Fast Open. 932 */ 933 tcp_v6_send_ack(sk, skb, (sk->sk_state == TCP_LISTEN) ? 934 tcp_rsk(req)->snt_isn + 1 : tcp_sk(sk)->snd_nxt, 935 tcp_rsk(req)->rcv_nxt, req->rsk_rcv_wnd, 936 tcp_time_stamp, req->ts_recent, sk->sk_bound_dev_if, 937 tcp_v6_md5_do_lookup(sk, &ipv6_hdr(skb)->daddr), 938 0, 0); 939 } 940 941 942 static struct sock *tcp_v6_cookie_check(struct sock *sk, struct sk_buff *skb) 943 { 944 #ifdef CONFIG_SYN_COOKIES 945 const struct tcphdr *th = tcp_hdr(skb); 946 947 if (!th->syn) 948 sk = cookie_v6_check(sk, skb); 949 #endif 950 return sk; 951 } 952 953 static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb) 954 { 955 if (skb->protocol == htons(ETH_P_IP)) 956 return tcp_v4_conn_request(sk, skb); 957 958 if (!ipv6_unicast_destination(skb)) 959 goto drop; 960 961 return tcp_conn_request(&tcp6_request_sock_ops, 962 &tcp_request_sock_ipv6_ops, sk, skb); 963 964 drop: 965 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS); 966 return 0; /* don't send reset */ 967 } 968 969 static struct sock *tcp_v6_syn_recv_sock(const struct sock *sk, struct sk_buff *skb, 970 struct request_sock *req, 971 struct dst_entry *dst, 972 struct request_sock *req_unhash, 973 bool *own_req) 974 { 975 struct inet_request_sock *ireq; 976 struct ipv6_pinfo *newnp; 977 const struct ipv6_pinfo *np = inet6_sk(sk); 978 struct ipv6_txoptions *opt; 979 struct tcp6_sock *newtcp6sk; 980 struct inet_sock *newinet; 981 struct tcp_sock *newtp; 982 struct sock *newsk; 983 #ifdef CONFIG_TCP_MD5SIG 984 struct tcp_md5sig_key *key; 985 #endif 986 struct flowi6 fl6; 987 988 if (skb->protocol == htons(ETH_P_IP)) { 989 /* 990 * v6 mapped 991 */ 992 993 newsk = tcp_v4_syn_recv_sock(sk, skb, req, dst, 994 req_unhash, own_req); 995 996 if (!newsk) 997 return NULL; 998 999 newtcp6sk = (struct tcp6_sock *)newsk; 1000 inet_sk(newsk)->pinet6 = &newtcp6sk->inet6; 1001 1002 newinet = inet_sk(newsk); 1003 newnp = inet6_sk(newsk); 1004 newtp = tcp_sk(newsk); 1005 1006 memcpy(newnp, np, sizeof(struct ipv6_pinfo)); 1007 1008 newnp->saddr = newsk->sk_v6_rcv_saddr; 1009 1010 inet_csk(newsk)->icsk_af_ops = &ipv6_mapped; 1011 newsk->sk_backlog_rcv = tcp_v4_do_rcv; 1012 #ifdef CONFIG_TCP_MD5SIG 1013 newtp->af_specific = &tcp_sock_ipv6_mapped_specific; 1014 #endif 1015 1016 newnp->ipv6_ac_list = NULL; 1017 newnp->ipv6_fl_list = NULL; 1018 newnp->pktoptions = NULL; 1019 newnp->opt = NULL; 1020 newnp->mcast_oif = tcp_v6_iif(skb); 1021 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit; 1022 newnp->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(skb)); 1023 if (np->repflow) 1024 newnp->flow_label = ip6_flowlabel(ipv6_hdr(skb)); 1025 1026 /* 1027 * No need to charge this sock to the relevant IPv6 refcnt debug socks count 1028 * here, tcp_create_openreq_child now does this for us, see the comment in 1029 * that function for the gory details. -acme 1030 */ 1031 1032 /* It is tricky place. Until this moment IPv4 tcp 1033 worked with IPv6 icsk.icsk_af_ops. 1034 Sync it now. 1035 */ 1036 tcp_sync_mss(newsk, inet_csk(newsk)->icsk_pmtu_cookie); 1037 1038 return newsk; 1039 } 1040 1041 ireq = inet_rsk(req); 1042 1043 if (sk_acceptq_is_full(sk)) 1044 goto out_overflow; 1045 1046 if (!dst) { 1047 dst = inet6_csk_route_req(sk, &fl6, req, IPPROTO_TCP); 1048 if (!dst) 1049 goto out; 1050 } 1051 1052 newsk = tcp_create_openreq_child(sk, req, skb); 1053 if (!newsk) 1054 goto out_nonewsk; 1055 1056 /* 1057 * No need to charge this sock to the relevant IPv6 refcnt debug socks 1058 * count here, tcp_create_openreq_child now does this for us, see the 1059 * comment in that function for the gory details. -acme 1060 */ 1061 1062 newsk->sk_gso_type = SKB_GSO_TCPV6; 1063 ip6_dst_store(newsk, dst, NULL, NULL); 1064 inet6_sk_rx_dst_set(newsk, skb); 1065 1066 newtcp6sk = (struct tcp6_sock *)newsk; 1067 inet_sk(newsk)->pinet6 = &newtcp6sk->inet6; 1068 1069 newtp = tcp_sk(newsk); 1070 newinet = inet_sk(newsk); 1071 newnp = inet6_sk(newsk); 1072 1073 memcpy(newnp, np, sizeof(struct ipv6_pinfo)); 1074 1075 newsk->sk_v6_daddr = ireq->ir_v6_rmt_addr; 1076 newnp->saddr = ireq->ir_v6_loc_addr; 1077 newsk->sk_v6_rcv_saddr = ireq->ir_v6_loc_addr; 1078 newsk->sk_bound_dev_if = ireq->ir_iif; 1079 1080 /* Now IPv6 options... 1081 1082 First: no IPv4 options. 1083 */ 1084 newinet->inet_opt = NULL; 1085 newnp->ipv6_ac_list = NULL; 1086 newnp->ipv6_fl_list = NULL; 1087 1088 /* Clone RX bits */ 1089 newnp->rxopt.all = np->rxopt.all; 1090 1091 newnp->pktoptions = NULL; 1092 newnp->opt = NULL; 1093 newnp->mcast_oif = tcp_v6_iif(skb); 1094 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit; 1095 newnp->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(skb)); 1096 if (np->repflow) 1097 newnp->flow_label = ip6_flowlabel(ipv6_hdr(skb)); 1098 1099 /* Clone native IPv6 options from listening socket (if any) 1100 1101 Yes, keeping reference count would be much more clever, 1102 but we make one more one thing there: reattach optmem 1103 to newsk. 1104 */ 1105 opt = rcu_dereference(np->opt); 1106 if (opt) { 1107 opt = ipv6_dup_options(newsk, opt); 1108 RCU_INIT_POINTER(newnp->opt, opt); 1109 } 1110 inet_csk(newsk)->icsk_ext_hdr_len = 0; 1111 if (opt) 1112 inet_csk(newsk)->icsk_ext_hdr_len = opt->opt_nflen + 1113 opt->opt_flen; 1114 1115 tcp_ca_openreq_child(newsk, dst); 1116 1117 tcp_sync_mss(newsk, dst_mtu(dst)); 1118 newtp->advmss = dst_metric_advmss(dst); 1119 if (tcp_sk(sk)->rx_opt.user_mss && 1120 tcp_sk(sk)->rx_opt.user_mss < newtp->advmss) 1121 newtp->advmss = tcp_sk(sk)->rx_opt.user_mss; 1122 1123 tcp_initialize_rcv_mss(newsk); 1124 1125 newinet->inet_daddr = newinet->inet_saddr = LOOPBACK4_IPV6; 1126 newinet->inet_rcv_saddr = LOOPBACK4_IPV6; 1127 1128 #ifdef CONFIG_TCP_MD5SIG 1129 /* Copy over the MD5 key from the original socket */ 1130 key = tcp_v6_md5_do_lookup(sk, &newsk->sk_v6_daddr); 1131 if (key) { 1132 /* We're using one, so create a matching key 1133 * on the newsk structure. If we fail to get 1134 * memory, then we end up not copying the key 1135 * across. Shucks. 1136 */ 1137 tcp_md5_do_add(newsk, (union tcp_md5_addr *)&newsk->sk_v6_daddr, 1138 AF_INET6, key->key, key->keylen, 1139 sk_gfp_mask(sk, GFP_ATOMIC)); 1140 } 1141 #endif 1142 1143 if (__inet_inherit_port(sk, newsk) < 0) { 1144 inet_csk_prepare_forced_close(newsk); 1145 tcp_done(newsk); 1146 goto out; 1147 } 1148 *own_req = inet_ehash_nolisten(newsk, req_to_sk(req_unhash)); 1149 if (*own_req) { 1150 tcp_move_syn(newtp, req); 1151 1152 /* Clone pktoptions received with SYN, if we own the req */ 1153 if (ireq->pktopts) { 1154 newnp->pktoptions = skb_clone(ireq->pktopts, 1155 sk_gfp_mask(sk, GFP_ATOMIC)); 1156 consume_skb(ireq->pktopts); 1157 ireq->pktopts = NULL; 1158 if (newnp->pktoptions) 1159 skb_set_owner_r(newnp->pktoptions, newsk); 1160 } 1161 } 1162 1163 return newsk; 1164 1165 out_overflow: 1166 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS); 1167 out_nonewsk: 1168 dst_release(dst); 1169 out: 1170 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS); 1171 return NULL; 1172 } 1173 1174 /* The socket must have it's spinlock held when we get 1175 * here, unless it is a TCP_LISTEN socket. 1176 * 1177 * We have a potential double-lock case here, so even when 1178 * doing backlog processing we use the BH locking scheme. 1179 * This is because we cannot sleep with the original spinlock 1180 * held. 1181 */ 1182 static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) 1183 { 1184 struct ipv6_pinfo *np = inet6_sk(sk); 1185 struct tcp_sock *tp; 1186 struct sk_buff *opt_skb = NULL; 1187 1188 /* Imagine: socket is IPv6. IPv4 packet arrives, 1189 goes to IPv4 receive handler and backlogged. 1190 From backlog it always goes here. Kerboom... 1191 Fortunately, tcp_rcv_established and rcv_established 1192 handle them correctly, but it is not case with 1193 tcp_v6_hnd_req and tcp_v6_send_reset(). --ANK 1194 */ 1195 1196 if (skb->protocol == htons(ETH_P_IP)) 1197 return tcp_v4_do_rcv(sk, skb); 1198 1199 if (sk_filter(sk, skb)) 1200 goto discard; 1201 1202 /* 1203 * socket locking is here for SMP purposes as backlog rcv 1204 * is currently called with bh processing disabled. 1205 */ 1206 1207 /* Do Stevens' IPV6_PKTOPTIONS. 1208 1209 Yes, guys, it is the only place in our code, where we 1210 may make it not affecting IPv4. 1211 The rest of code is protocol independent, 1212 and I do not like idea to uglify IPv4. 1213 1214 Actually, all the idea behind IPV6_PKTOPTIONS 1215 looks not very well thought. For now we latch 1216 options, received in the last packet, enqueued 1217 by tcp. Feel free to propose better solution. 1218 --ANK (980728) 1219 */ 1220 if (np->rxopt.all) 1221 opt_skb = skb_clone(skb, sk_gfp_mask(sk, GFP_ATOMIC)); 1222 1223 if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */ 1224 struct dst_entry *dst = sk->sk_rx_dst; 1225 1226 sock_rps_save_rxhash(sk, skb); 1227 sk_mark_napi_id(sk, skb); 1228 if (dst) { 1229 if (inet_sk(sk)->rx_dst_ifindex != skb->skb_iif || 1230 dst->ops->check(dst, np->rx_dst_cookie) == NULL) { 1231 dst_release(dst); 1232 sk->sk_rx_dst = NULL; 1233 } 1234 } 1235 1236 tcp_rcv_established(sk, skb, tcp_hdr(skb), skb->len); 1237 if (opt_skb) 1238 goto ipv6_pktoptions; 1239 return 0; 1240 } 1241 1242 if (tcp_checksum_complete(skb)) 1243 goto csum_err; 1244 1245 if (sk->sk_state == TCP_LISTEN) { 1246 struct sock *nsk = tcp_v6_cookie_check(sk, skb); 1247 1248 if (!nsk) 1249 goto discard; 1250 1251 if (nsk != sk) { 1252 sock_rps_save_rxhash(nsk, skb); 1253 sk_mark_napi_id(nsk, skb); 1254 if (tcp_child_process(sk, nsk, skb)) 1255 goto reset; 1256 if (opt_skb) 1257 __kfree_skb(opt_skb); 1258 return 0; 1259 } 1260 } else 1261 sock_rps_save_rxhash(sk, skb); 1262 1263 if (tcp_rcv_state_process(sk, skb)) 1264 goto reset; 1265 if (opt_skb) 1266 goto ipv6_pktoptions; 1267 return 0; 1268 1269 reset: 1270 tcp_v6_send_reset(sk, skb); 1271 discard: 1272 if (opt_skb) 1273 __kfree_skb(opt_skb); 1274 kfree_skb(skb); 1275 return 0; 1276 csum_err: 1277 TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_CSUMERRORS); 1278 TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_INERRS); 1279 goto discard; 1280 1281 1282 ipv6_pktoptions: 1283 /* Do you ask, what is it? 1284 1285 1. skb was enqueued by tcp. 1286 2. skb is added to tail of read queue, rather than out of order. 1287 3. socket is not in passive state. 1288 4. Finally, it really contains options, which user wants to receive. 1289 */ 1290 tp = tcp_sk(sk); 1291 if (TCP_SKB_CB(opt_skb)->end_seq == tp->rcv_nxt && 1292 !((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))) { 1293 if (np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo) 1294 np->mcast_oif = tcp_v6_iif(opt_skb); 1295 if (np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) 1296 np->mcast_hops = ipv6_hdr(opt_skb)->hop_limit; 1297 if (np->rxopt.bits.rxflow || np->rxopt.bits.rxtclass) 1298 np->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(opt_skb)); 1299 if (np->repflow) 1300 np->flow_label = ip6_flowlabel(ipv6_hdr(opt_skb)); 1301 if (ipv6_opt_accepted(sk, opt_skb, &TCP_SKB_CB(opt_skb)->header.h6)) { 1302 skb_set_owner_r(opt_skb, sk); 1303 opt_skb = xchg(&np->pktoptions, opt_skb); 1304 } else { 1305 __kfree_skb(opt_skb); 1306 opt_skb = xchg(&np->pktoptions, NULL); 1307 } 1308 } 1309 1310 kfree_skb(opt_skb); 1311 return 0; 1312 } 1313 1314 static void tcp_v6_fill_cb(struct sk_buff *skb, const struct ipv6hdr *hdr, 1315 const struct tcphdr *th) 1316 { 1317 /* This is tricky: we move IP6CB at its correct location into 1318 * TCP_SKB_CB(). It must be done after xfrm6_policy_check(), because 1319 * _decode_session6() uses IP6CB(). 1320 * barrier() makes sure compiler won't play aliasing games. 1321 */ 1322 memmove(&TCP_SKB_CB(skb)->header.h6, IP6CB(skb), 1323 sizeof(struct inet6_skb_parm)); 1324 barrier(); 1325 1326 TCP_SKB_CB(skb)->seq = ntohl(th->seq); 1327 TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin + 1328 skb->len - th->doff*4); 1329 TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq); 1330 TCP_SKB_CB(skb)->tcp_flags = tcp_flag_byte(th); 1331 TCP_SKB_CB(skb)->tcp_tw_isn = 0; 1332 TCP_SKB_CB(skb)->ip_dsfield = ipv6_get_dsfield(hdr); 1333 TCP_SKB_CB(skb)->sacked = 0; 1334 } 1335 1336 static void tcp_v6_restore_cb(struct sk_buff *skb) 1337 { 1338 /* We need to move header back to the beginning if xfrm6_policy_check() 1339 * and tcp_v6_fill_cb() are going to be called again. 1340 */ 1341 memmove(IP6CB(skb), &TCP_SKB_CB(skb)->header.h6, 1342 sizeof(struct inet6_skb_parm)); 1343 } 1344 1345 static int tcp_v6_rcv(struct sk_buff *skb) 1346 { 1347 const struct tcphdr *th; 1348 const struct ipv6hdr *hdr; 1349 struct sock *sk; 1350 int ret; 1351 struct net *net = dev_net(skb->dev); 1352 1353 if (skb->pkt_type != PACKET_HOST) 1354 goto discard_it; 1355 1356 /* 1357 * Count it even if it's bad. 1358 */ 1359 TCP_INC_STATS_BH(net, TCP_MIB_INSEGS); 1360 1361 if (!pskb_may_pull(skb, sizeof(struct tcphdr))) 1362 goto discard_it; 1363 1364 th = tcp_hdr(skb); 1365 1366 if (th->doff < sizeof(struct tcphdr)/4) 1367 goto bad_packet; 1368 if (!pskb_may_pull(skb, th->doff*4)) 1369 goto discard_it; 1370 1371 if (skb_checksum_init(skb, IPPROTO_TCP, ip6_compute_pseudo)) 1372 goto csum_error; 1373 1374 th = tcp_hdr(skb); 1375 hdr = ipv6_hdr(skb); 1376 1377 lookup: 1378 sk = __inet6_lookup_skb(&tcp_hashinfo, skb, th->source, th->dest, 1379 inet6_iif(skb)); 1380 if (!sk) 1381 goto no_tcp_socket; 1382 1383 process: 1384 if (sk->sk_state == TCP_TIME_WAIT) 1385 goto do_time_wait; 1386 1387 if (sk->sk_state == TCP_NEW_SYN_RECV) { 1388 struct request_sock *req = inet_reqsk(sk); 1389 struct sock *nsk = NULL; 1390 1391 sk = req->rsk_listener; 1392 tcp_v6_fill_cb(skb, hdr, th); 1393 if (tcp_v6_inbound_md5_hash(sk, skb)) { 1394 reqsk_put(req); 1395 goto discard_it; 1396 } 1397 if (likely(sk->sk_state == TCP_LISTEN)) { 1398 nsk = tcp_check_req(sk, skb, req, false); 1399 } else { 1400 inet_csk_reqsk_queue_drop_and_put(sk, req); 1401 goto lookup; 1402 } 1403 if (!nsk) { 1404 reqsk_put(req); 1405 goto discard_it; 1406 } 1407 if (nsk == sk) { 1408 sock_hold(sk); 1409 reqsk_put(req); 1410 tcp_v6_restore_cb(skb); 1411 } else if (tcp_child_process(sk, nsk, skb)) { 1412 tcp_v6_send_reset(nsk, skb); 1413 goto discard_it; 1414 } else { 1415 return 0; 1416 } 1417 } 1418 if (hdr->hop_limit < inet6_sk(sk)->min_hopcount) { 1419 NET_INC_STATS_BH(net, LINUX_MIB_TCPMINTTLDROP); 1420 goto discard_and_relse; 1421 } 1422 1423 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) 1424 goto discard_and_relse; 1425 1426 tcp_v6_fill_cb(skb, hdr, th); 1427 1428 if (tcp_v6_inbound_md5_hash(sk, skb)) 1429 goto discard_and_relse; 1430 1431 if (sk_filter(sk, skb)) 1432 goto discard_and_relse; 1433 1434 skb->dev = NULL; 1435 1436 if (sk->sk_state == TCP_LISTEN) { 1437 ret = tcp_v6_do_rcv(sk, skb); 1438 goto put_and_return; 1439 } 1440 1441 sk_incoming_cpu_update(sk); 1442 1443 bh_lock_sock_nested(sk); 1444 tcp_sk(sk)->segs_in += max_t(u16, 1, skb_shinfo(skb)->gso_segs); 1445 ret = 0; 1446 if (!sock_owned_by_user(sk)) { 1447 if (!tcp_prequeue(sk, skb)) 1448 ret = tcp_v6_do_rcv(sk, skb); 1449 } else if (unlikely(sk_add_backlog(sk, skb, 1450 sk->sk_rcvbuf + sk->sk_sndbuf))) { 1451 bh_unlock_sock(sk); 1452 NET_INC_STATS_BH(net, LINUX_MIB_TCPBACKLOGDROP); 1453 goto discard_and_relse; 1454 } 1455 bh_unlock_sock(sk); 1456 1457 put_and_return: 1458 sock_put(sk); 1459 return ret ? -1 : 0; 1460 1461 no_tcp_socket: 1462 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 1463 goto discard_it; 1464 1465 tcp_v6_fill_cb(skb, hdr, th); 1466 1467 if (tcp_checksum_complete(skb)) { 1468 csum_error: 1469 TCP_INC_STATS_BH(net, TCP_MIB_CSUMERRORS); 1470 bad_packet: 1471 TCP_INC_STATS_BH(net, TCP_MIB_INERRS); 1472 } else { 1473 tcp_v6_send_reset(NULL, skb); 1474 } 1475 1476 discard_it: 1477 kfree_skb(skb); 1478 return 0; 1479 1480 discard_and_relse: 1481 sock_put(sk); 1482 goto discard_it; 1483 1484 do_time_wait: 1485 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) { 1486 inet_twsk_put(inet_twsk(sk)); 1487 goto discard_it; 1488 } 1489 1490 tcp_v6_fill_cb(skb, hdr, th); 1491 1492 if (tcp_checksum_complete(skb)) { 1493 inet_twsk_put(inet_twsk(sk)); 1494 goto csum_error; 1495 } 1496 1497 switch (tcp_timewait_state_process(inet_twsk(sk), skb, th)) { 1498 case TCP_TW_SYN: 1499 { 1500 struct sock *sk2; 1501 1502 sk2 = inet6_lookup_listener(dev_net(skb->dev), &tcp_hashinfo, 1503 &ipv6_hdr(skb)->saddr, th->source, 1504 &ipv6_hdr(skb)->daddr, 1505 ntohs(th->dest), tcp_v6_iif(skb)); 1506 if (sk2) { 1507 struct inet_timewait_sock *tw = inet_twsk(sk); 1508 inet_twsk_deschedule_put(tw); 1509 sk = sk2; 1510 tcp_v6_restore_cb(skb); 1511 goto process; 1512 } 1513 /* Fall through to ACK */ 1514 } 1515 case TCP_TW_ACK: 1516 tcp_v6_timewait_ack(sk, skb); 1517 break; 1518 case TCP_TW_RST: 1519 tcp_v6_restore_cb(skb); 1520 tcp_v6_send_reset(sk, skb); 1521 inet_twsk_deschedule_put(inet_twsk(sk)); 1522 goto discard_it; 1523 case TCP_TW_SUCCESS: 1524 ; 1525 } 1526 goto discard_it; 1527 } 1528 1529 static void tcp_v6_early_demux(struct sk_buff *skb) 1530 { 1531 const struct ipv6hdr *hdr; 1532 const struct tcphdr *th; 1533 struct sock *sk; 1534 1535 if (skb->pkt_type != PACKET_HOST) 1536 return; 1537 1538 if (!pskb_may_pull(skb, skb_transport_offset(skb) + sizeof(struct tcphdr))) 1539 return; 1540 1541 hdr = ipv6_hdr(skb); 1542 th = tcp_hdr(skb); 1543 1544 if (th->doff < sizeof(struct tcphdr) / 4) 1545 return; 1546 1547 /* Note : We use inet6_iif() here, not tcp_v6_iif() */ 1548 sk = __inet6_lookup_established(dev_net(skb->dev), &tcp_hashinfo, 1549 &hdr->saddr, th->source, 1550 &hdr->daddr, ntohs(th->dest), 1551 inet6_iif(skb)); 1552 if (sk) { 1553 skb->sk = sk; 1554 skb->destructor = sock_edemux; 1555 if (sk_fullsock(sk)) { 1556 struct dst_entry *dst = READ_ONCE(sk->sk_rx_dst); 1557 1558 if (dst) 1559 dst = dst_check(dst, inet6_sk(sk)->rx_dst_cookie); 1560 if (dst && 1561 inet_sk(sk)->rx_dst_ifindex == skb->skb_iif) 1562 skb_dst_set_noref(skb, dst); 1563 } 1564 } 1565 } 1566 1567 static struct timewait_sock_ops tcp6_timewait_sock_ops = { 1568 .twsk_obj_size = sizeof(struct tcp6_timewait_sock), 1569 .twsk_unique = tcp_twsk_unique, 1570 .twsk_destructor = tcp_twsk_destructor, 1571 }; 1572 1573 static const struct inet_connection_sock_af_ops ipv6_specific = { 1574 .queue_xmit = inet6_csk_xmit, 1575 .send_check = tcp_v6_send_check, 1576 .rebuild_header = inet6_sk_rebuild_header, 1577 .sk_rx_dst_set = inet6_sk_rx_dst_set, 1578 .conn_request = tcp_v6_conn_request, 1579 .syn_recv_sock = tcp_v6_syn_recv_sock, 1580 .net_header_len = sizeof(struct ipv6hdr), 1581 .net_frag_header_len = sizeof(struct frag_hdr), 1582 .setsockopt = ipv6_setsockopt, 1583 .getsockopt = ipv6_getsockopt, 1584 .addr2sockaddr = inet6_csk_addr2sockaddr, 1585 .sockaddr_len = sizeof(struct sockaddr_in6), 1586 .bind_conflict = inet6_csk_bind_conflict, 1587 #ifdef CONFIG_COMPAT 1588 .compat_setsockopt = compat_ipv6_setsockopt, 1589 .compat_getsockopt = compat_ipv6_getsockopt, 1590 #endif 1591 .mtu_reduced = tcp_v6_mtu_reduced, 1592 }; 1593 1594 #ifdef CONFIG_TCP_MD5SIG 1595 static const struct tcp_sock_af_ops tcp_sock_ipv6_specific = { 1596 .md5_lookup = tcp_v6_md5_lookup, 1597 .calc_md5_hash = tcp_v6_md5_hash_skb, 1598 .md5_parse = tcp_v6_parse_md5_keys, 1599 }; 1600 #endif 1601 1602 /* 1603 * TCP over IPv4 via INET6 API 1604 */ 1605 static const struct inet_connection_sock_af_ops ipv6_mapped = { 1606 .queue_xmit = ip_queue_xmit, 1607 .send_check = tcp_v4_send_check, 1608 .rebuild_header = inet_sk_rebuild_header, 1609 .sk_rx_dst_set = inet_sk_rx_dst_set, 1610 .conn_request = tcp_v6_conn_request, 1611 .syn_recv_sock = tcp_v6_syn_recv_sock, 1612 .net_header_len = sizeof(struct iphdr), 1613 .setsockopt = ipv6_setsockopt, 1614 .getsockopt = ipv6_getsockopt, 1615 .addr2sockaddr = inet6_csk_addr2sockaddr, 1616 .sockaddr_len = sizeof(struct sockaddr_in6), 1617 .bind_conflict = inet6_csk_bind_conflict, 1618 #ifdef CONFIG_COMPAT 1619 .compat_setsockopt = compat_ipv6_setsockopt, 1620 .compat_getsockopt = compat_ipv6_getsockopt, 1621 #endif 1622 .mtu_reduced = tcp_v4_mtu_reduced, 1623 }; 1624 1625 #ifdef CONFIG_TCP_MD5SIG 1626 static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific = { 1627 .md5_lookup = tcp_v4_md5_lookup, 1628 .calc_md5_hash = tcp_v4_md5_hash_skb, 1629 .md5_parse = tcp_v6_parse_md5_keys, 1630 }; 1631 #endif 1632 1633 /* NOTE: A lot of things set to zero explicitly by call to 1634 * sk_alloc() so need not be done here. 1635 */ 1636 static int tcp_v6_init_sock(struct sock *sk) 1637 { 1638 struct inet_connection_sock *icsk = inet_csk(sk); 1639 1640 tcp_init_sock(sk); 1641 1642 icsk->icsk_af_ops = &ipv6_specific; 1643 1644 #ifdef CONFIG_TCP_MD5SIG 1645 tcp_sk(sk)->af_specific = &tcp_sock_ipv6_specific; 1646 #endif 1647 1648 return 0; 1649 } 1650 1651 static void tcp_v6_destroy_sock(struct sock *sk) 1652 { 1653 tcp_v4_destroy_sock(sk); 1654 inet6_destroy_sock(sk); 1655 } 1656 1657 #ifdef CONFIG_PROC_FS 1658 /* Proc filesystem TCPv6 sock list dumping. */ 1659 static void get_openreq6(struct seq_file *seq, 1660 const struct request_sock *req, int i) 1661 { 1662 long ttd = req->rsk_timer.expires - jiffies; 1663 const struct in6_addr *src = &inet_rsk(req)->ir_v6_loc_addr; 1664 const struct in6_addr *dest = &inet_rsk(req)->ir_v6_rmt_addr; 1665 1666 if (ttd < 0) 1667 ttd = 0; 1668 1669 seq_printf(seq, 1670 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1671 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %d %d %pK\n", 1672 i, 1673 src->s6_addr32[0], src->s6_addr32[1], 1674 src->s6_addr32[2], src->s6_addr32[3], 1675 inet_rsk(req)->ir_num, 1676 dest->s6_addr32[0], dest->s6_addr32[1], 1677 dest->s6_addr32[2], dest->s6_addr32[3], 1678 ntohs(inet_rsk(req)->ir_rmt_port), 1679 TCP_SYN_RECV, 1680 0, 0, /* could print option size, but that is af dependent. */ 1681 1, /* timers active (only the expire timer) */ 1682 jiffies_to_clock_t(ttd), 1683 req->num_timeout, 1684 from_kuid_munged(seq_user_ns(seq), 1685 sock_i_uid(req->rsk_listener)), 1686 0, /* non standard timer */ 1687 0, /* open_requests have no inode */ 1688 0, req); 1689 } 1690 1691 static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i) 1692 { 1693 const struct in6_addr *dest, *src; 1694 __u16 destp, srcp; 1695 int timer_active; 1696 unsigned long timer_expires; 1697 const struct inet_sock *inet = inet_sk(sp); 1698 const struct tcp_sock *tp = tcp_sk(sp); 1699 const struct inet_connection_sock *icsk = inet_csk(sp); 1700 const struct fastopen_queue *fastopenq = &icsk->icsk_accept_queue.fastopenq; 1701 int rx_queue; 1702 int state; 1703 1704 dest = &sp->sk_v6_daddr; 1705 src = &sp->sk_v6_rcv_saddr; 1706 destp = ntohs(inet->inet_dport); 1707 srcp = ntohs(inet->inet_sport); 1708 1709 if (icsk->icsk_pending == ICSK_TIME_RETRANS) { 1710 timer_active = 1; 1711 timer_expires = icsk->icsk_timeout; 1712 } else if (icsk->icsk_pending == ICSK_TIME_PROBE0) { 1713 timer_active = 4; 1714 timer_expires = icsk->icsk_timeout; 1715 } else if (timer_pending(&sp->sk_timer)) { 1716 timer_active = 2; 1717 timer_expires = sp->sk_timer.expires; 1718 } else { 1719 timer_active = 0; 1720 timer_expires = jiffies; 1721 } 1722 1723 state = sk_state_load(sp); 1724 if (state == TCP_LISTEN) 1725 rx_queue = sp->sk_ack_backlog; 1726 else 1727 /* Because we don't lock the socket, 1728 * we might find a transient negative value. 1729 */ 1730 rx_queue = max_t(int, tp->rcv_nxt - tp->copied_seq, 0); 1731 1732 seq_printf(seq, 1733 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1734 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %lu %lu %u %u %d\n", 1735 i, 1736 src->s6_addr32[0], src->s6_addr32[1], 1737 src->s6_addr32[2], src->s6_addr32[3], srcp, 1738 dest->s6_addr32[0], dest->s6_addr32[1], 1739 dest->s6_addr32[2], dest->s6_addr32[3], destp, 1740 state, 1741 tp->write_seq - tp->snd_una, 1742 rx_queue, 1743 timer_active, 1744 jiffies_delta_to_clock_t(timer_expires - jiffies), 1745 icsk->icsk_retransmits, 1746 from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)), 1747 icsk->icsk_probes_out, 1748 sock_i_ino(sp), 1749 atomic_read(&sp->sk_refcnt), sp, 1750 jiffies_to_clock_t(icsk->icsk_rto), 1751 jiffies_to_clock_t(icsk->icsk_ack.ato), 1752 (icsk->icsk_ack.quick << 1) | icsk->icsk_ack.pingpong, 1753 tp->snd_cwnd, 1754 state == TCP_LISTEN ? 1755 fastopenq->max_qlen : 1756 (tcp_in_initial_slowstart(tp) ? -1 : tp->snd_ssthresh) 1757 ); 1758 } 1759 1760 static void get_timewait6_sock(struct seq_file *seq, 1761 struct inet_timewait_sock *tw, int i) 1762 { 1763 long delta = tw->tw_timer.expires - jiffies; 1764 const struct in6_addr *dest, *src; 1765 __u16 destp, srcp; 1766 1767 dest = &tw->tw_v6_daddr; 1768 src = &tw->tw_v6_rcv_saddr; 1769 destp = ntohs(tw->tw_dport); 1770 srcp = ntohs(tw->tw_sport); 1771 1772 seq_printf(seq, 1773 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1774 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK\n", 1775 i, 1776 src->s6_addr32[0], src->s6_addr32[1], 1777 src->s6_addr32[2], src->s6_addr32[3], srcp, 1778 dest->s6_addr32[0], dest->s6_addr32[1], 1779 dest->s6_addr32[2], dest->s6_addr32[3], destp, 1780 tw->tw_substate, 0, 0, 1781 3, jiffies_delta_to_clock_t(delta), 0, 0, 0, 0, 1782 atomic_read(&tw->tw_refcnt), tw); 1783 } 1784 1785 static int tcp6_seq_show(struct seq_file *seq, void *v) 1786 { 1787 struct tcp_iter_state *st; 1788 struct sock *sk = v; 1789 1790 if (v == SEQ_START_TOKEN) { 1791 seq_puts(seq, 1792 " sl " 1793 "local_address " 1794 "remote_address " 1795 "st tx_queue rx_queue tr tm->when retrnsmt" 1796 " uid timeout inode\n"); 1797 goto out; 1798 } 1799 st = seq->private; 1800 1801 if (sk->sk_state == TCP_TIME_WAIT) 1802 get_timewait6_sock(seq, v, st->num); 1803 else if (sk->sk_state == TCP_NEW_SYN_RECV) 1804 get_openreq6(seq, v, st->num); 1805 else 1806 get_tcp6_sock(seq, v, st->num); 1807 out: 1808 return 0; 1809 } 1810 1811 static const struct file_operations tcp6_afinfo_seq_fops = { 1812 .owner = THIS_MODULE, 1813 .open = tcp_seq_open, 1814 .read = seq_read, 1815 .llseek = seq_lseek, 1816 .release = seq_release_net 1817 }; 1818 1819 static struct tcp_seq_afinfo tcp6_seq_afinfo = { 1820 .name = "tcp6", 1821 .family = AF_INET6, 1822 .seq_fops = &tcp6_afinfo_seq_fops, 1823 .seq_ops = { 1824 .show = tcp6_seq_show, 1825 }, 1826 }; 1827 1828 int __net_init tcp6_proc_init(struct net *net) 1829 { 1830 return tcp_proc_register(net, &tcp6_seq_afinfo); 1831 } 1832 1833 void tcp6_proc_exit(struct net *net) 1834 { 1835 tcp_proc_unregister(net, &tcp6_seq_afinfo); 1836 } 1837 #endif 1838 1839 static void tcp_v6_clear_sk(struct sock *sk, int size) 1840 { 1841 struct inet_sock *inet = inet_sk(sk); 1842 1843 /* we do not want to clear pinet6 field, because of RCU lookups */ 1844 sk_prot_clear_nulls(sk, offsetof(struct inet_sock, pinet6)); 1845 1846 size -= offsetof(struct inet_sock, pinet6) + sizeof(inet->pinet6); 1847 memset(&inet->pinet6 + 1, 0, size); 1848 } 1849 1850 struct proto tcpv6_prot = { 1851 .name = "TCPv6", 1852 .owner = THIS_MODULE, 1853 .close = tcp_close, 1854 .connect = tcp_v6_connect, 1855 .disconnect = tcp_disconnect, 1856 .accept = inet_csk_accept, 1857 .ioctl = tcp_ioctl, 1858 .init = tcp_v6_init_sock, 1859 .destroy = tcp_v6_destroy_sock, 1860 .shutdown = tcp_shutdown, 1861 .setsockopt = tcp_setsockopt, 1862 .getsockopt = tcp_getsockopt, 1863 .recvmsg = tcp_recvmsg, 1864 .sendmsg = tcp_sendmsg, 1865 .sendpage = tcp_sendpage, 1866 .backlog_rcv = tcp_v6_do_rcv, 1867 .release_cb = tcp_release_cb, 1868 .hash = inet_hash, 1869 .unhash = inet_unhash, 1870 .get_port = inet_csk_get_port, 1871 .enter_memory_pressure = tcp_enter_memory_pressure, 1872 .stream_memory_free = tcp_stream_memory_free, 1873 .sockets_allocated = &tcp_sockets_allocated, 1874 .memory_allocated = &tcp_memory_allocated, 1875 .memory_pressure = &tcp_memory_pressure, 1876 .orphan_count = &tcp_orphan_count, 1877 .sysctl_mem = sysctl_tcp_mem, 1878 .sysctl_wmem = sysctl_tcp_wmem, 1879 .sysctl_rmem = sysctl_tcp_rmem, 1880 .max_header = MAX_TCP_HEADER, 1881 .obj_size = sizeof(struct tcp6_sock), 1882 .slab_flags = SLAB_DESTROY_BY_RCU, 1883 .twsk_prot = &tcp6_timewait_sock_ops, 1884 .rsk_prot = &tcp6_request_sock_ops, 1885 .h.hashinfo = &tcp_hashinfo, 1886 .no_autobind = true, 1887 #ifdef CONFIG_COMPAT 1888 .compat_setsockopt = compat_tcp_setsockopt, 1889 .compat_getsockopt = compat_tcp_getsockopt, 1890 #endif 1891 .clear_sk = tcp_v6_clear_sk, 1892 .diag_destroy = tcp_abort, 1893 }; 1894 1895 static const struct inet6_protocol tcpv6_protocol = { 1896 .early_demux = tcp_v6_early_demux, 1897 .handler = tcp_v6_rcv, 1898 .err_handler = tcp_v6_err, 1899 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 1900 }; 1901 1902 static struct inet_protosw tcpv6_protosw = { 1903 .type = SOCK_STREAM, 1904 .protocol = IPPROTO_TCP, 1905 .prot = &tcpv6_prot, 1906 .ops = &inet6_stream_ops, 1907 .flags = INET_PROTOSW_PERMANENT | 1908 INET_PROTOSW_ICSK, 1909 }; 1910 1911 static int __net_init tcpv6_net_init(struct net *net) 1912 { 1913 return inet_ctl_sock_create(&net->ipv6.tcp_sk, PF_INET6, 1914 SOCK_RAW, IPPROTO_TCP, net); 1915 } 1916 1917 static void __net_exit tcpv6_net_exit(struct net *net) 1918 { 1919 inet_ctl_sock_destroy(net->ipv6.tcp_sk); 1920 } 1921 1922 static void __net_exit tcpv6_net_exit_batch(struct list_head *net_exit_list) 1923 { 1924 inet_twsk_purge(&tcp_hashinfo, &tcp_death_row, AF_INET6); 1925 } 1926 1927 static struct pernet_operations tcpv6_net_ops = { 1928 .init = tcpv6_net_init, 1929 .exit = tcpv6_net_exit, 1930 .exit_batch = tcpv6_net_exit_batch, 1931 }; 1932 1933 int __init tcpv6_init(void) 1934 { 1935 int ret; 1936 1937 ret = inet6_add_protocol(&tcpv6_protocol, IPPROTO_TCP); 1938 if (ret) 1939 goto out; 1940 1941 /* register inet6 protocol */ 1942 ret = inet6_register_protosw(&tcpv6_protosw); 1943 if (ret) 1944 goto out_tcpv6_protocol; 1945 1946 ret = register_pernet_subsys(&tcpv6_net_ops); 1947 if (ret) 1948 goto out_tcpv6_protosw; 1949 out: 1950 return ret; 1951 1952 out_tcpv6_protosw: 1953 inet6_unregister_protosw(&tcpv6_protosw); 1954 out_tcpv6_protocol: 1955 inet6_del_protocol(&tcpv6_protocol, IPPROTO_TCP); 1956 goto out; 1957 } 1958 1959 void tcpv6_exit(void) 1960 { 1961 unregister_pernet_subsys(&tcpv6_net_ops); 1962 inet6_unregister_protosw(&tcpv6_protosw); 1963 inet6_del_protocol(&tcpv6_protocol, IPPROTO_TCP); 1964 } 1965