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/tcp_memcontrol.h> 65 #include <net/busy_poll.h> 66 67 #include <linux/proc_fs.h> 68 #include <linux/seq_file.h> 69 70 #include <linux/crypto.h> 71 #include <linux/scatterlist.h> 72 73 static void tcp_v6_send_reset(struct sock *sk, struct sk_buff *skb); 74 static void tcp_v6_reqsk_send_ack(struct sock *sk, struct sk_buff *skb, 75 struct request_sock *req); 76 77 static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb); 78 79 static const struct inet_connection_sock_af_ops ipv6_mapped; 80 static const struct inet_connection_sock_af_ops ipv6_specific; 81 #ifdef CONFIG_TCP_MD5SIG 82 static const struct tcp_sock_af_ops tcp_sock_ipv6_specific; 83 static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific; 84 #else 85 static struct tcp_md5sig_key *tcp_v6_md5_do_lookup(struct sock *sk, 86 const struct in6_addr *addr) 87 { 88 return NULL; 89 } 90 #endif 91 92 static void inet6_sk_rx_dst_set(struct sock *sk, const struct sk_buff *skb) 93 { 94 struct dst_entry *dst = skb_dst(skb); 95 96 if (dst) { 97 const struct rt6_info *rt = (const struct rt6_info *)dst; 98 99 dst_hold(dst); 100 sk->sk_rx_dst = dst; 101 inet_sk(sk)->rx_dst_ifindex = skb->skb_iif; 102 inet6_sk(sk)->rx_dst_cookie = rt6_get_cookie(rt); 103 } 104 } 105 106 static __u32 tcp_v6_init_sequence(const struct sk_buff *skb) 107 { 108 return secure_tcpv6_sequence_number(ipv6_hdr(skb)->daddr.s6_addr32, 109 ipv6_hdr(skb)->saddr.s6_addr32, 110 tcp_hdr(skb)->dest, 111 tcp_hdr(skb)->source); 112 } 113 114 static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr, 115 int addr_len) 116 { 117 struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr; 118 struct inet_sock *inet = inet_sk(sk); 119 struct inet_connection_sock *icsk = inet_csk(sk); 120 struct ipv6_pinfo *np = inet6_sk(sk); 121 struct tcp_sock *tp = tcp_sk(sk); 122 struct in6_addr *saddr = NULL, *final_p, final; 123 struct rt6_info *rt; 124 struct flowi6 fl6; 125 struct dst_entry *dst; 126 int addr_type; 127 int err; 128 129 if (addr_len < SIN6_LEN_RFC2133) 130 return -EINVAL; 131 132 if (usin->sin6_family != AF_INET6) 133 return -EAFNOSUPPORT; 134 135 memset(&fl6, 0, sizeof(fl6)); 136 137 if (np->sndflow) { 138 fl6.flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK; 139 IP6_ECN_flow_init(fl6.flowlabel); 140 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) { 141 struct ip6_flowlabel *flowlabel; 142 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel); 143 if (!flowlabel) 144 return -EINVAL; 145 fl6_sock_release(flowlabel); 146 } 147 } 148 149 /* 150 * connect() to INADDR_ANY means loopback (BSD'ism). 151 */ 152 153 if (ipv6_addr_any(&usin->sin6_addr)) 154 usin->sin6_addr.s6_addr[15] = 0x1; 155 156 addr_type = ipv6_addr_type(&usin->sin6_addr); 157 158 if (addr_type & IPV6_ADDR_MULTICAST) 159 return -ENETUNREACH; 160 161 if (addr_type&IPV6_ADDR_LINKLOCAL) { 162 if (addr_len >= sizeof(struct sockaddr_in6) && 163 usin->sin6_scope_id) { 164 /* If interface is set while binding, indices 165 * must coincide. 166 */ 167 if (sk->sk_bound_dev_if && 168 sk->sk_bound_dev_if != usin->sin6_scope_id) 169 return -EINVAL; 170 171 sk->sk_bound_dev_if = usin->sin6_scope_id; 172 } 173 174 /* Connect to link-local address requires an interface */ 175 if (!sk->sk_bound_dev_if) 176 return -EINVAL; 177 } 178 179 if (tp->rx_opt.ts_recent_stamp && 180 !ipv6_addr_equal(&sk->sk_v6_daddr, &usin->sin6_addr)) { 181 tp->rx_opt.ts_recent = 0; 182 tp->rx_opt.ts_recent_stamp = 0; 183 tp->write_seq = 0; 184 } 185 186 sk->sk_v6_daddr = usin->sin6_addr; 187 np->flow_label = fl6.flowlabel; 188 189 /* 190 * TCP over IPv4 191 */ 192 193 if (addr_type == IPV6_ADDR_MAPPED) { 194 u32 exthdrlen = icsk->icsk_ext_hdr_len; 195 struct sockaddr_in sin; 196 197 SOCK_DEBUG(sk, "connect: ipv4 mapped\n"); 198 199 if (__ipv6_only_sock(sk)) 200 return -ENETUNREACH; 201 202 sin.sin_family = AF_INET; 203 sin.sin_port = usin->sin6_port; 204 sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3]; 205 206 icsk->icsk_af_ops = &ipv6_mapped; 207 sk->sk_backlog_rcv = tcp_v4_do_rcv; 208 #ifdef CONFIG_TCP_MD5SIG 209 tp->af_specific = &tcp_sock_ipv6_mapped_specific; 210 #endif 211 212 err = tcp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin)); 213 214 if (err) { 215 icsk->icsk_ext_hdr_len = exthdrlen; 216 icsk->icsk_af_ops = &ipv6_specific; 217 sk->sk_backlog_rcv = tcp_v6_do_rcv; 218 #ifdef CONFIG_TCP_MD5SIG 219 tp->af_specific = &tcp_sock_ipv6_specific; 220 #endif 221 goto failure; 222 } 223 np->saddr = sk->sk_v6_rcv_saddr; 224 225 return err; 226 } 227 228 if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) 229 saddr = &sk->sk_v6_rcv_saddr; 230 231 fl6.flowi6_proto = IPPROTO_TCP; 232 fl6.daddr = sk->sk_v6_daddr; 233 fl6.saddr = saddr ? *saddr : np->saddr; 234 fl6.flowi6_oif = sk->sk_bound_dev_if; 235 fl6.flowi6_mark = sk->sk_mark; 236 fl6.fl6_dport = usin->sin6_port; 237 fl6.fl6_sport = inet->inet_sport; 238 239 final_p = fl6_update_dst(&fl6, np->opt, &final); 240 241 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6)); 242 243 dst = ip6_dst_lookup_flow(sk, &fl6, final_p); 244 if (IS_ERR(dst)) { 245 err = PTR_ERR(dst); 246 goto failure; 247 } 248 249 if (!saddr) { 250 saddr = &fl6.saddr; 251 sk->sk_v6_rcv_saddr = *saddr; 252 } 253 254 /* set the source address */ 255 np->saddr = *saddr; 256 inet->inet_rcv_saddr = LOOPBACK4_IPV6; 257 258 sk->sk_gso_type = SKB_GSO_TCPV6; 259 __ip6_dst_store(sk, dst, NULL, NULL); 260 261 rt = (struct rt6_info *) dst; 262 if (tcp_death_row.sysctl_tw_recycle && 263 !tp->rx_opt.ts_recent_stamp && 264 ipv6_addr_equal(&fl6.daddr, &sk->sk_v6_daddr)) 265 tcp_fetch_timewait_stamp(sk, dst); 266 267 icsk->icsk_ext_hdr_len = 0; 268 if (np->opt) 269 icsk->icsk_ext_hdr_len = (np->opt->opt_flen + 270 np->opt->opt_nflen); 271 272 tp->rx_opt.mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - sizeof(struct ipv6hdr); 273 274 inet->inet_dport = usin->sin6_port; 275 276 tcp_set_state(sk, TCP_SYN_SENT); 277 err = inet6_hash_connect(&tcp_death_row, sk); 278 if (err) 279 goto late_failure; 280 281 ip6_set_txhash(sk); 282 283 if (!tp->write_seq && likely(!tp->repair)) 284 tp->write_seq = secure_tcpv6_sequence_number(np->saddr.s6_addr32, 285 sk->sk_v6_daddr.s6_addr32, 286 inet->inet_sport, 287 inet->inet_dport); 288 289 err = tcp_connect(sk); 290 if (err) 291 goto late_failure; 292 293 return 0; 294 295 late_failure: 296 tcp_set_state(sk, TCP_CLOSE); 297 __sk_dst_reset(sk); 298 failure: 299 inet->inet_dport = 0; 300 sk->sk_route_caps = 0; 301 return err; 302 } 303 304 static void tcp_v6_mtu_reduced(struct sock *sk) 305 { 306 struct dst_entry *dst; 307 308 if ((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) 309 return; 310 311 dst = inet6_csk_update_pmtu(sk, tcp_sk(sk)->mtu_info); 312 if (!dst) 313 return; 314 315 if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst)) { 316 tcp_sync_mss(sk, dst_mtu(dst)); 317 tcp_simple_retransmit(sk); 318 } 319 } 320 321 static void tcp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 322 u8 type, u8 code, int offset, __be32 info) 323 { 324 const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data; 325 const struct tcphdr *th = (struct tcphdr *)(skb->data+offset); 326 struct net *net = dev_net(skb->dev); 327 struct request_sock *fastopen; 328 struct ipv6_pinfo *np; 329 struct tcp_sock *tp; 330 __u32 seq, snd_una; 331 struct sock *sk; 332 int err; 333 334 sk = __inet6_lookup_established(net, &tcp_hashinfo, 335 &hdr->daddr, th->dest, 336 &hdr->saddr, ntohs(th->source), 337 skb->dev->ifindex); 338 339 if (!sk) { 340 ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev), 341 ICMP6_MIB_INERRORS); 342 return; 343 } 344 345 if (sk->sk_state == TCP_TIME_WAIT) { 346 inet_twsk_put(inet_twsk(sk)); 347 return; 348 } 349 seq = ntohl(th->seq); 350 if (sk->sk_state == TCP_NEW_SYN_RECV) 351 return tcp_req_err(sk, seq); 352 353 bh_lock_sock(sk); 354 if (sock_owned_by_user(sk) && type != ICMPV6_PKT_TOOBIG) 355 NET_INC_STATS_BH(net, LINUX_MIB_LOCKDROPPEDICMPS); 356 357 if (sk->sk_state == TCP_CLOSE) 358 goto out; 359 360 if (ipv6_hdr(skb)->hop_limit < inet6_sk(sk)->min_hopcount) { 361 NET_INC_STATS_BH(net, LINUX_MIB_TCPMINTTLDROP); 362 goto out; 363 } 364 365 tp = tcp_sk(sk); 366 /* XXX (TFO) - tp->snd_una should be ISN (tcp_create_openreq_child() */ 367 fastopen = tp->fastopen_rsk; 368 snd_una = fastopen ? tcp_rsk(fastopen)->snt_isn : tp->snd_una; 369 if (sk->sk_state != TCP_LISTEN && 370 !between(seq, snd_una, tp->snd_nxt)) { 371 NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS); 372 goto out; 373 } 374 375 np = inet6_sk(sk); 376 377 if (type == NDISC_REDIRECT) { 378 struct dst_entry *dst = __sk_dst_check(sk, np->dst_cookie); 379 380 if (dst) 381 dst->ops->redirect(dst, sk, skb); 382 goto out; 383 } 384 385 if (type == ICMPV6_PKT_TOOBIG) { 386 /* We are not interested in TCP_LISTEN and open_requests 387 * (SYN-ACKs send out by Linux are always <576bytes so 388 * they should go through unfragmented). 389 */ 390 if (sk->sk_state == TCP_LISTEN) 391 goto out; 392 393 if (!ip6_sk_accept_pmtu(sk)) 394 goto out; 395 396 tp->mtu_info = ntohl(info); 397 if (!sock_owned_by_user(sk)) 398 tcp_v6_mtu_reduced(sk); 399 else if (!test_and_set_bit(TCP_MTU_REDUCED_DEFERRED, 400 &tp->tsq_flags)) 401 sock_hold(sk); 402 goto out; 403 } 404 405 icmpv6_err_convert(type, code, &err); 406 407 /* Might be for an request_sock */ 408 switch (sk->sk_state) { 409 case TCP_SYN_SENT: 410 case TCP_SYN_RECV: 411 /* Only in fast or simultaneous open. If a fast open socket is 412 * is already accepted it is treated as a connected one below. 413 */ 414 if (fastopen && !fastopen->sk) 415 break; 416 417 if (!sock_owned_by_user(sk)) { 418 sk->sk_err = err; 419 sk->sk_error_report(sk); /* Wake people up to see the error (see connect in sock.c) */ 420 421 tcp_done(sk); 422 } else 423 sk->sk_err_soft = err; 424 goto out; 425 } 426 427 if (!sock_owned_by_user(sk) && np->recverr) { 428 sk->sk_err = err; 429 sk->sk_error_report(sk); 430 } else 431 sk->sk_err_soft = err; 432 433 out: 434 bh_unlock_sock(sk); 435 sock_put(sk); 436 } 437 438 439 static int tcp_v6_send_synack(struct sock *sk, struct dst_entry *dst, 440 struct flowi *fl, 441 struct request_sock *req, 442 u16 queue_mapping, 443 struct tcp_fastopen_cookie *foc) 444 { 445 struct inet_request_sock *ireq = inet_rsk(req); 446 struct ipv6_pinfo *np = inet6_sk(sk); 447 struct flowi6 *fl6 = &fl->u.ip6; 448 struct sk_buff *skb; 449 int err = -ENOMEM; 450 451 /* First, grab a route. */ 452 if (!dst && (dst = inet6_csk_route_req(sk, fl6, req)) == NULL) 453 goto done; 454 455 skb = tcp_make_synack(sk, dst, req, foc); 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 skb_set_queue_mapping(skb, queue_mapping); 466 err = ip6_xmit(sk, skb, fl6, np->opt, np->tclass); 467 err = net_xmit_eval(err); 468 } 469 470 done: 471 return err; 472 } 473 474 475 static void tcp_v6_reqsk_destructor(struct request_sock *req) 476 { 477 kfree_skb(inet_rsk(req)->pktopts); 478 } 479 480 #ifdef CONFIG_TCP_MD5SIG 481 static struct tcp_md5sig_key *tcp_v6_md5_do_lookup(struct sock *sk, 482 const struct in6_addr *addr) 483 { 484 return tcp_md5_do_lookup(sk, (union tcp_md5_addr *)addr, AF_INET6); 485 } 486 487 static struct tcp_md5sig_key *tcp_v6_md5_lookup(struct sock *sk, 488 const struct sock *addr_sk) 489 { 490 return tcp_v6_md5_do_lookup(sk, &addr_sk->sk_v6_daddr); 491 } 492 493 static int tcp_v6_parse_md5_keys(struct sock *sk, char __user *optval, 494 int optlen) 495 { 496 struct tcp_md5sig cmd; 497 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&cmd.tcpm_addr; 498 499 if (optlen < sizeof(cmd)) 500 return -EINVAL; 501 502 if (copy_from_user(&cmd, optval, sizeof(cmd))) 503 return -EFAULT; 504 505 if (sin6->sin6_family != AF_INET6) 506 return -EINVAL; 507 508 if (!cmd.tcpm_keylen) { 509 if (ipv6_addr_v4mapped(&sin6->sin6_addr)) 510 return tcp_md5_do_del(sk, (union tcp_md5_addr *)&sin6->sin6_addr.s6_addr32[3], 511 AF_INET); 512 return tcp_md5_do_del(sk, (union tcp_md5_addr *)&sin6->sin6_addr, 513 AF_INET6); 514 } 515 516 if (cmd.tcpm_keylen > TCP_MD5SIG_MAXKEYLEN) 517 return -EINVAL; 518 519 if (ipv6_addr_v4mapped(&sin6->sin6_addr)) 520 return tcp_md5_do_add(sk, (union tcp_md5_addr *)&sin6->sin6_addr.s6_addr32[3], 521 AF_INET, cmd.tcpm_key, cmd.tcpm_keylen, GFP_KERNEL); 522 523 return tcp_md5_do_add(sk, (union tcp_md5_addr *)&sin6->sin6_addr, 524 AF_INET6, cmd.tcpm_key, cmd.tcpm_keylen, GFP_KERNEL); 525 } 526 527 static int tcp_v6_md5_hash_pseudoheader(struct tcp_md5sig_pool *hp, 528 const struct in6_addr *daddr, 529 const struct in6_addr *saddr, int nbytes) 530 { 531 struct tcp6_pseudohdr *bp; 532 struct scatterlist sg; 533 534 bp = &hp->md5_blk.ip6; 535 /* 1. TCP pseudo-header (RFC2460) */ 536 bp->saddr = *saddr; 537 bp->daddr = *daddr; 538 bp->protocol = cpu_to_be32(IPPROTO_TCP); 539 bp->len = cpu_to_be32(nbytes); 540 541 sg_init_one(&sg, bp, sizeof(*bp)); 542 return crypto_hash_update(&hp->md5_desc, &sg, sizeof(*bp)); 543 } 544 545 static int tcp_v6_md5_hash_hdr(char *md5_hash, struct tcp_md5sig_key *key, 546 const struct in6_addr *daddr, struct in6_addr *saddr, 547 const struct tcphdr *th) 548 { 549 struct tcp_md5sig_pool *hp; 550 struct hash_desc *desc; 551 552 hp = tcp_get_md5sig_pool(); 553 if (!hp) 554 goto clear_hash_noput; 555 desc = &hp->md5_desc; 556 557 if (crypto_hash_init(desc)) 558 goto clear_hash; 559 if (tcp_v6_md5_hash_pseudoheader(hp, daddr, saddr, th->doff << 2)) 560 goto clear_hash; 561 if (tcp_md5_hash_header(hp, th)) 562 goto clear_hash; 563 if (tcp_md5_hash_key(hp, key)) 564 goto clear_hash; 565 if (crypto_hash_final(desc, md5_hash)) 566 goto clear_hash; 567 568 tcp_put_md5sig_pool(); 569 return 0; 570 571 clear_hash: 572 tcp_put_md5sig_pool(); 573 clear_hash_noput: 574 memset(md5_hash, 0, 16); 575 return 1; 576 } 577 578 static int tcp_v6_md5_hash_skb(char *md5_hash, 579 const struct tcp_md5sig_key *key, 580 const struct sock *sk, 581 const struct sk_buff *skb) 582 { 583 const struct in6_addr *saddr, *daddr; 584 struct tcp_md5sig_pool *hp; 585 struct hash_desc *desc; 586 const struct tcphdr *th = tcp_hdr(skb); 587 588 if (sk) { /* valid for establish/request sockets */ 589 saddr = &sk->sk_v6_rcv_saddr; 590 daddr = &sk->sk_v6_daddr; 591 } else { 592 const struct ipv6hdr *ip6h = ipv6_hdr(skb); 593 saddr = &ip6h->saddr; 594 daddr = &ip6h->daddr; 595 } 596 597 hp = tcp_get_md5sig_pool(); 598 if (!hp) 599 goto clear_hash_noput; 600 desc = &hp->md5_desc; 601 602 if (crypto_hash_init(desc)) 603 goto clear_hash; 604 605 if (tcp_v6_md5_hash_pseudoheader(hp, daddr, saddr, skb->len)) 606 goto clear_hash; 607 if (tcp_md5_hash_header(hp, th)) 608 goto clear_hash; 609 if (tcp_md5_hash_skb_data(hp, skb, th->doff << 2)) 610 goto clear_hash; 611 if (tcp_md5_hash_key(hp, key)) 612 goto clear_hash; 613 if (crypto_hash_final(desc, md5_hash)) 614 goto clear_hash; 615 616 tcp_put_md5sig_pool(); 617 return 0; 618 619 clear_hash: 620 tcp_put_md5sig_pool(); 621 clear_hash_noput: 622 memset(md5_hash, 0, 16); 623 return 1; 624 } 625 626 static bool tcp_v6_inbound_md5_hash(struct sock *sk, const struct sk_buff *skb) 627 { 628 const __u8 *hash_location = NULL; 629 struct tcp_md5sig_key *hash_expected; 630 const struct ipv6hdr *ip6h = ipv6_hdr(skb); 631 const struct tcphdr *th = tcp_hdr(skb); 632 int genhash; 633 u8 newhash[16]; 634 635 hash_expected = tcp_v6_md5_do_lookup(sk, &ip6h->saddr); 636 hash_location = tcp_parse_md5sig_option(th); 637 638 /* We've parsed the options - do we have a hash? */ 639 if (!hash_expected && !hash_location) 640 return false; 641 642 if (hash_expected && !hash_location) { 643 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND); 644 return true; 645 } 646 647 if (!hash_expected && hash_location) { 648 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED); 649 return true; 650 } 651 652 /* check the signature */ 653 genhash = tcp_v6_md5_hash_skb(newhash, 654 hash_expected, 655 NULL, skb); 656 657 if (genhash || memcmp(hash_location, newhash, 16) != 0) { 658 net_info_ratelimited("MD5 Hash %s for [%pI6c]:%u->[%pI6c]:%u\n", 659 genhash ? "failed" : "mismatch", 660 &ip6h->saddr, ntohs(th->source), 661 &ip6h->daddr, ntohs(th->dest)); 662 return true; 663 } 664 return false; 665 } 666 #endif 667 668 static void tcp_v6_init_req(struct request_sock *req, struct sock *sk, 669 struct sk_buff *skb) 670 { 671 struct inet_request_sock *ireq = inet_rsk(req); 672 struct ipv6_pinfo *np = inet6_sk(sk); 673 674 ireq->ir_v6_rmt_addr = ipv6_hdr(skb)->saddr; 675 ireq->ir_v6_loc_addr = ipv6_hdr(skb)->daddr; 676 677 /* So that link locals have meaning */ 678 if (!sk->sk_bound_dev_if && 679 ipv6_addr_type(&ireq->ir_v6_rmt_addr) & IPV6_ADDR_LINKLOCAL) 680 ireq->ir_iif = tcp_v6_iif(skb); 681 682 if (!TCP_SKB_CB(skb)->tcp_tw_isn && 683 (ipv6_opt_accepted(sk, skb, &TCP_SKB_CB(skb)->header.h6) || 684 np->rxopt.bits.rxinfo || 685 np->rxopt.bits.rxoinfo || np->rxopt.bits.rxhlim || 686 np->rxopt.bits.rxohlim || np->repflow)) { 687 atomic_inc(&skb->users); 688 ireq->pktopts = skb; 689 } 690 } 691 692 static struct dst_entry *tcp_v6_route_req(struct sock *sk, struct flowi *fl, 693 const struct request_sock *req, 694 bool *strict) 695 { 696 if (strict) 697 *strict = true; 698 return inet6_csk_route_req(sk, &fl->u.ip6, req); 699 } 700 701 struct request_sock_ops tcp6_request_sock_ops __read_mostly = { 702 .family = AF_INET6, 703 .obj_size = sizeof(struct tcp6_request_sock), 704 .rtx_syn_ack = tcp_rtx_synack, 705 .send_ack = tcp_v6_reqsk_send_ack, 706 .destructor = tcp_v6_reqsk_destructor, 707 .send_reset = tcp_v6_send_reset, 708 .syn_ack_timeout = tcp_syn_ack_timeout, 709 }; 710 711 static const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops = { 712 .mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - 713 sizeof(struct ipv6hdr), 714 #ifdef CONFIG_TCP_MD5SIG 715 .req_md5_lookup = tcp_v6_md5_lookup, 716 .calc_md5_hash = tcp_v6_md5_hash_skb, 717 #endif 718 .init_req = tcp_v6_init_req, 719 #ifdef CONFIG_SYN_COOKIES 720 .cookie_init_seq = cookie_v6_init_sequence, 721 #endif 722 .route_req = tcp_v6_route_req, 723 .init_seq = tcp_v6_init_sequence, 724 .send_synack = tcp_v6_send_synack, 725 .queue_hash_add = inet6_csk_reqsk_queue_hash_add, 726 }; 727 728 static void tcp_v6_send_response(struct sock *sk, struct sk_buff *skb, u32 seq, 729 u32 ack, u32 win, u32 tsval, u32 tsecr, 730 int oif, struct tcp_md5sig_key *key, int rst, 731 u8 tclass, u32 label) 732 { 733 const struct tcphdr *th = tcp_hdr(skb); 734 struct tcphdr *t1; 735 struct sk_buff *buff; 736 struct flowi6 fl6; 737 struct net *net = sk ? sock_net(sk) : dev_net(skb_dst(skb)->dev); 738 struct sock *ctl_sk = net->ipv6.tcp_sk; 739 unsigned int tot_len = sizeof(struct tcphdr); 740 struct dst_entry *dst; 741 __be32 *topt; 742 743 if (tsecr) 744 tot_len += TCPOLEN_TSTAMP_ALIGNED; 745 #ifdef CONFIG_TCP_MD5SIG 746 if (key) 747 tot_len += TCPOLEN_MD5SIG_ALIGNED; 748 #endif 749 750 buff = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + tot_len, 751 GFP_ATOMIC); 752 if (!buff) 753 return; 754 755 skb_reserve(buff, MAX_HEADER + sizeof(struct ipv6hdr) + tot_len); 756 757 t1 = (struct tcphdr *) skb_push(buff, tot_len); 758 skb_reset_transport_header(buff); 759 760 /* Swap the send and the receive. */ 761 memset(t1, 0, sizeof(*t1)); 762 t1->dest = th->source; 763 t1->source = th->dest; 764 t1->doff = tot_len / 4; 765 t1->seq = htonl(seq); 766 t1->ack_seq = htonl(ack); 767 t1->ack = !rst || !th->ack; 768 t1->rst = rst; 769 t1->window = htons(win); 770 771 topt = (__be32 *)(t1 + 1); 772 773 if (tsecr) { 774 *topt++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | 775 (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP); 776 *topt++ = htonl(tsval); 777 *topt++ = htonl(tsecr); 778 } 779 780 #ifdef CONFIG_TCP_MD5SIG 781 if (key) { 782 *topt++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | 783 (TCPOPT_MD5SIG << 8) | TCPOLEN_MD5SIG); 784 tcp_v6_md5_hash_hdr((__u8 *)topt, key, 785 &ipv6_hdr(skb)->saddr, 786 &ipv6_hdr(skb)->daddr, t1); 787 } 788 #endif 789 790 memset(&fl6, 0, sizeof(fl6)); 791 fl6.daddr = ipv6_hdr(skb)->saddr; 792 fl6.saddr = ipv6_hdr(skb)->daddr; 793 fl6.flowlabel = label; 794 795 buff->ip_summed = CHECKSUM_PARTIAL; 796 buff->csum = 0; 797 798 __tcp_v6_send_check(buff, &fl6.saddr, &fl6.daddr); 799 800 fl6.flowi6_proto = IPPROTO_TCP; 801 if (rt6_need_strict(&fl6.daddr) && !oif) 802 fl6.flowi6_oif = tcp_v6_iif(skb); 803 else 804 fl6.flowi6_oif = oif; 805 fl6.flowi6_mark = IP6_REPLY_MARK(net, skb->mark); 806 fl6.fl6_dport = t1->dest; 807 fl6.fl6_sport = t1->source; 808 security_skb_classify_flow(skb, flowi6_to_flowi(&fl6)); 809 810 /* Pass a socket to ip6_dst_lookup either it is for RST 811 * Underlying function will use this to retrieve the network 812 * namespace 813 */ 814 dst = ip6_dst_lookup_flow(ctl_sk, &fl6, NULL); 815 if (!IS_ERR(dst)) { 816 skb_dst_set(buff, dst); 817 ip6_xmit(ctl_sk, buff, &fl6, NULL, tclass); 818 TCP_INC_STATS_BH(net, TCP_MIB_OUTSEGS); 819 if (rst) 820 TCP_INC_STATS_BH(net, TCP_MIB_OUTRSTS); 821 return; 822 } 823 824 kfree_skb(buff); 825 } 826 827 static void tcp_v6_send_reset(struct sock *sk, struct sk_buff *skb) 828 { 829 const struct tcphdr *th = tcp_hdr(skb); 830 u32 seq = 0, ack_seq = 0; 831 struct tcp_md5sig_key *key = NULL; 832 #ifdef CONFIG_TCP_MD5SIG 833 const __u8 *hash_location = NULL; 834 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 835 unsigned char newhash[16]; 836 int genhash; 837 struct sock *sk1 = NULL; 838 #endif 839 int oif; 840 841 if (th->rst) 842 return; 843 844 /* If sk not NULL, it means we did a successful lookup and incoming 845 * route had to be correct. prequeue might have dropped our dst. 846 */ 847 if (!sk && !ipv6_unicast_destination(skb)) 848 return; 849 850 #ifdef CONFIG_TCP_MD5SIG 851 hash_location = tcp_parse_md5sig_option(th); 852 if (!sk && hash_location) { 853 /* 854 * active side is lost. Try to find listening socket through 855 * source port, and then find md5 key through listening socket. 856 * we are not loose security here: 857 * Incoming packet is checked with md5 hash with finding key, 858 * no RST generated if md5 hash doesn't match. 859 */ 860 sk1 = inet6_lookup_listener(dev_net(skb_dst(skb)->dev), 861 &tcp_hashinfo, &ipv6h->saddr, 862 th->source, &ipv6h->daddr, 863 ntohs(th->source), tcp_v6_iif(skb)); 864 if (!sk1) 865 return; 866 867 rcu_read_lock(); 868 key = tcp_v6_md5_do_lookup(sk1, &ipv6h->saddr); 869 if (!key) 870 goto release_sk1; 871 872 genhash = tcp_v6_md5_hash_skb(newhash, key, NULL, skb); 873 if (genhash || memcmp(hash_location, newhash, 16) != 0) 874 goto release_sk1; 875 } else { 876 key = sk ? tcp_v6_md5_do_lookup(sk, &ipv6h->saddr) : NULL; 877 } 878 #endif 879 880 if (th->ack) 881 seq = ntohl(th->ack_seq); 882 else 883 ack_seq = ntohl(th->seq) + th->syn + th->fin + skb->len - 884 (th->doff << 2); 885 886 oif = sk ? sk->sk_bound_dev_if : 0; 887 tcp_v6_send_response(sk, skb, seq, ack_seq, 0, 0, 0, oif, key, 1, 0, 0); 888 889 #ifdef CONFIG_TCP_MD5SIG 890 release_sk1: 891 if (sk1) { 892 rcu_read_unlock(); 893 sock_put(sk1); 894 } 895 #endif 896 } 897 898 static void tcp_v6_send_ack(struct sock *sk, struct sk_buff *skb, u32 seq, 899 u32 ack, u32 win, u32 tsval, u32 tsecr, int oif, 900 struct tcp_md5sig_key *key, u8 tclass, 901 u32 label) 902 { 903 tcp_v6_send_response(sk, skb, seq, ack, win, tsval, tsecr, oif, key, 0, 904 tclass, label); 905 } 906 907 static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb) 908 { 909 struct inet_timewait_sock *tw = inet_twsk(sk); 910 struct tcp_timewait_sock *tcptw = tcp_twsk(sk); 911 912 tcp_v6_send_ack(sk, skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt, 913 tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale, 914 tcp_time_stamp + tcptw->tw_ts_offset, 915 tcptw->tw_ts_recent, tw->tw_bound_dev_if, tcp_twsk_md5_key(tcptw), 916 tw->tw_tclass, cpu_to_be32(tw->tw_flowlabel)); 917 918 inet_twsk_put(tw); 919 } 920 921 static void tcp_v6_reqsk_send_ack(struct sock *sk, struct sk_buff *skb, 922 struct request_sock *req) 923 { 924 /* sk->sk_state == TCP_LISTEN -> for regular TCP_SYN_RECV 925 * sk->sk_state == TCP_SYN_RECV -> for Fast Open. 926 */ 927 tcp_v6_send_ack(sk, skb, (sk->sk_state == TCP_LISTEN) ? 928 tcp_rsk(req)->snt_isn + 1 : tcp_sk(sk)->snd_nxt, 929 tcp_rsk(req)->rcv_nxt, req->rcv_wnd, 930 tcp_time_stamp, req->ts_recent, sk->sk_bound_dev_if, 931 tcp_v6_md5_do_lookup(sk, &ipv6_hdr(skb)->daddr), 932 0, 0); 933 } 934 935 936 static struct sock *tcp_v6_hnd_req(struct sock *sk, struct sk_buff *skb) 937 { 938 const struct tcphdr *th = tcp_hdr(skb); 939 struct request_sock *req; 940 struct sock *nsk; 941 942 /* Find possible connection requests. */ 943 req = inet6_csk_search_req(sk, th->source, 944 &ipv6_hdr(skb)->saddr, 945 &ipv6_hdr(skb)->daddr, tcp_v6_iif(skb)); 946 if (req) { 947 nsk = tcp_check_req(sk, skb, req, false); 948 if (!nsk) 949 reqsk_put(req); 950 return nsk; 951 } 952 nsk = __inet6_lookup_established(sock_net(sk), &tcp_hashinfo, 953 &ipv6_hdr(skb)->saddr, th->source, 954 &ipv6_hdr(skb)->daddr, ntohs(th->dest), 955 tcp_v6_iif(skb)); 956 957 if (nsk) { 958 if (nsk->sk_state != TCP_TIME_WAIT) { 959 bh_lock_sock(nsk); 960 return nsk; 961 } 962 inet_twsk_put(inet_twsk(nsk)); 963 return NULL; 964 } 965 966 #ifdef CONFIG_SYN_COOKIES 967 if (!th->syn) 968 sk = cookie_v6_check(sk, skb); 969 #endif 970 return sk; 971 } 972 973 static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb) 974 { 975 if (skb->protocol == htons(ETH_P_IP)) 976 return tcp_v4_conn_request(sk, skb); 977 978 if (!ipv6_unicast_destination(skb)) 979 goto drop; 980 981 return tcp_conn_request(&tcp6_request_sock_ops, 982 &tcp_request_sock_ipv6_ops, sk, skb); 983 984 drop: 985 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS); 986 return 0; /* don't send reset */ 987 } 988 989 static struct sock *tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb, 990 struct request_sock *req, 991 struct dst_entry *dst) 992 { 993 struct inet_request_sock *ireq; 994 struct ipv6_pinfo *newnp, *np = inet6_sk(sk); 995 struct tcp6_sock *newtcp6sk; 996 struct inet_sock *newinet; 997 struct tcp_sock *newtp; 998 struct sock *newsk; 999 #ifdef CONFIG_TCP_MD5SIG 1000 struct tcp_md5sig_key *key; 1001 #endif 1002 struct flowi6 fl6; 1003 1004 if (skb->protocol == htons(ETH_P_IP)) { 1005 /* 1006 * v6 mapped 1007 */ 1008 1009 newsk = tcp_v4_syn_recv_sock(sk, skb, req, dst); 1010 1011 if (!newsk) 1012 return NULL; 1013 1014 newtcp6sk = (struct tcp6_sock *)newsk; 1015 inet_sk(newsk)->pinet6 = &newtcp6sk->inet6; 1016 1017 newinet = inet_sk(newsk); 1018 newnp = inet6_sk(newsk); 1019 newtp = tcp_sk(newsk); 1020 1021 memcpy(newnp, np, sizeof(struct ipv6_pinfo)); 1022 1023 newnp->saddr = newsk->sk_v6_rcv_saddr; 1024 1025 inet_csk(newsk)->icsk_af_ops = &ipv6_mapped; 1026 newsk->sk_backlog_rcv = tcp_v4_do_rcv; 1027 #ifdef CONFIG_TCP_MD5SIG 1028 newtp->af_specific = &tcp_sock_ipv6_mapped_specific; 1029 #endif 1030 1031 newnp->ipv6_ac_list = NULL; 1032 newnp->ipv6_fl_list = NULL; 1033 newnp->pktoptions = NULL; 1034 newnp->opt = NULL; 1035 newnp->mcast_oif = tcp_v6_iif(skb); 1036 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit; 1037 newnp->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(skb)); 1038 if (np->repflow) 1039 newnp->flow_label = ip6_flowlabel(ipv6_hdr(skb)); 1040 1041 /* 1042 * No need to charge this sock to the relevant IPv6 refcnt debug socks count 1043 * here, tcp_create_openreq_child now does this for us, see the comment in 1044 * that function for the gory details. -acme 1045 */ 1046 1047 /* It is tricky place. Until this moment IPv4 tcp 1048 worked with IPv6 icsk.icsk_af_ops. 1049 Sync it now. 1050 */ 1051 tcp_sync_mss(newsk, inet_csk(newsk)->icsk_pmtu_cookie); 1052 1053 return newsk; 1054 } 1055 1056 ireq = inet_rsk(req); 1057 1058 if (sk_acceptq_is_full(sk)) 1059 goto out_overflow; 1060 1061 if (!dst) { 1062 dst = inet6_csk_route_req(sk, &fl6, req); 1063 if (!dst) 1064 goto out; 1065 } 1066 1067 newsk = tcp_create_openreq_child(sk, req, skb); 1068 if (!newsk) 1069 goto out_nonewsk; 1070 1071 /* 1072 * No need to charge this sock to the relevant IPv6 refcnt debug socks 1073 * count here, tcp_create_openreq_child now does this for us, see the 1074 * comment in that function for the gory details. -acme 1075 */ 1076 1077 newsk->sk_gso_type = SKB_GSO_TCPV6; 1078 __ip6_dst_store(newsk, dst, NULL, NULL); 1079 inet6_sk_rx_dst_set(newsk, skb); 1080 1081 newtcp6sk = (struct tcp6_sock *)newsk; 1082 inet_sk(newsk)->pinet6 = &newtcp6sk->inet6; 1083 1084 newtp = tcp_sk(newsk); 1085 newinet = inet_sk(newsk); 1086 newnp = inet6_sk(newsk); 1087 1088 memcpy(newnp, np, sizeof(struct ipv6_pinfo)); 1089 1090 newsk->sk_v6_daddr = ireq->ir_v6_rmt_addr; 1091 newnp->saddr = ireq->ir_v6_loc_addr; 1092 newsk->sk_v6_rcv_saddr = ireq->ir_v6_loc_addr; 1093 newsk->sk_bound_dev_if = ireq->ir_iif; 1094 1095 ip6_set_txhash(newsk); 1096 1097 /* Now IPv6 options... 1098 1099 First: no IPv4 options. 1100 */ 1101 newinet->inet_opt = NULL; 1102 newnp->ipv6_ac_list = NULL; 1103 newnp->ipv6_fl_list = NULL; 1104 1105 /* Clone RX bits */ 1106 newnp->rxopt.all = np->rxopt.all; 1107 1108 /* Clone pktoptions received with SYN */ 1109 newnp->pktoptions = NULL; 1110 if (ireq->pktopts) { 1111 newnp->pktoptions = skb_clone(ireq->pktopts, 1112 sk_gfp_atomic(sk, GFP_ATOMIC)); 1113 consume_skb(ireq->pktopts); 1114 ireq->pktopts = NULL; 1115 if (newnp->pktoptions) 1116 skb_set_owner_r(newnp->pktoptions, newsk); 1117 } 1118 newnp->opt = NULL; 1119 newnp->mcast_oif = tcp_v6_iif(skb); 1120 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit; 1121 newnp->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(skb)); 1122 if (np->repflow) 1123 newnp->flow_label = ip6_flowlabel(ipv6_hdr(skb)); 1124 1125 /* Clone native IPv6 options from listening socket (if any) 1126 1127 Yes, keeping reference count would be much more clever, 1128 but we make one more one thing there: reattach optmem 1129 to newsk. 1130 */ 1131 if (np->opt) 1132 newnp->opt = ipv6_dup_options(newsk, np->opt); 1133 1134 inet_csk(newsk)->icsk_ext_hdr_len = 0; 1135 if (newnp->opt) 1136 inet_csk(newsk)->icsk_ext_hdr_len = (newnp->opt->opt_nflen + 1137 newnp->opt->opt_flen); 1138 1139 tcp_ca_openreq_child(newsk, dst); 1140 1141 tcp_sync_mss(newsk, dst_mtu(dst)); 1142 newtp->advmss = dst_metric_advmss(dst); 1143 if (tcp_sk(sk)->rx_opt.user_mss && 1144 tcp_sk(sk)->rx_opt.user_mss < newtp->advmss) 1145 newtp->advmss = tcp_sk(sk)->rx_opt.user_mss; 1146 1147 tcp_initialize_rcv_mss(newsk); 1148 1149 newinet->inet_daddr = newinet->inet_saddr = LOOPBACK4_IPV6; 1150 newinet->inet_rcv_saddr = LOOPBACK4_IPV6; 1151 1152 #ifdef CONFIG_TCP_MD5SIG 1153 /* Copy over the MD5 key from the original socket */ 1154 key = tcp_v6_md5_do_lookup(sk, &newsk->sk_v6_daddr); 1155 if (key) { 1156 /* We're using one, so create a matching key 1157 * on the newsk structure. If we fail to get 1158 * memory, then we end up not copying the key 1159 * across. Shucks. 1160 */ 1161 tcp_md5_do_add(newsk, (union tcp_md5_addr *)&newsk->sk_v6_daddr, 1162 AF_INET6, key->key, key->keylen, 1163 sk_gfp_atomic(sk, GFP_ATOMIC)); 1164 } 1165 #endif 1166 1167 if (__inet_inherit_port(sk, newsk) < 0) { 1168 inet_csk_prepare_forced_close(newsk); 1169 tcp_done(newsk); 1170 goto out; 1171 } 1172 __inet_hash(newsk, NULL); 1173 1174 return newsk; 1175 1176 out_overflow: 1177 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS); 1178 out_nonewsk: 1179 dst_release(dst); 1180 out: 1181 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS); 1182 return NULL; 1183 } 1184 1185 /* The socket must have it's spinlock held when we get 1186 * here. 1187 * 1188 * We have a potential double-lock case here, so even when 1189 * doing backlog processing we use the BH locking scheme. 1190 * This is because we cannot sleep with the original spinlock 1191 * held. 1192 */ 1193 static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) 1194 { 1195 struct ipv6_pinfo *np = inet6_sk(sk); 1196 struct tcp_sock *tp; 1197 struct sk_buff *opt_skb = NULL; 1198 1199 /* Imagine: socket is IPv6. IPv4 packet arrives, 1200 goes to IPv4 receive handler and backlogged. 1201 From backlog it always goes here. Kerboom... 1202 Fortunately, tcp_rcv_established and rcv_established 1203 handle them correctly, but it is not case with 1204 tcp_v6_hnd_req and tcp_v6_send_reset(). --ANK 1205 */ 1206 1207 if (skb->protocol == htons(ETH_P_IP)) 1208 return tcp_v4_do_rcv(sk, skb); 1209 1210 if (sk_filter(sk, skb)) 1211 goto discard; 1212 1213 /* 1214 * socket locking is here for SMP purposes as backlog rcv 1215 * is currently called with bh processing disabled. 1216 */ 1217 1218 /* Do Stevens' IPV6_PKTOPTIONS. 1219 1220 Yes, guys, it is the only place in our code, where we 1221 may make it not affecting IPv4. 1222 The rest of code is protocol independent, 1223 and I do not like idea to uglify IPv4. 1224 1225 Actually, all the idea behind IPV6_PKTOPTIONS 1226 looks not very well thought. For now we latch 1227 options, received in the last packet, enqueued 1228 by tcp. Feel free to propose better solution. 1229 --ANK (980728) 1230 */ 1231 if (np->rxopt.all) 1232 opt_skb = skb_clone(skb, sk_gfp_atomic(sk, GFP_ATOMIC)); 1233 1234 if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */ 1235 struct dst_entry *dst = sk->sk_rx_dst; 1236 1237 sock_rps_save_rxhash(sk, skb); 1238 sk_mark_napi_id(sk, skb); 1239 if (dst) { 1240 if (inet_sk(sk)->rx_dst_ifindex != skb->skb_iif || 1241 dst->ops->check(dst, np->rx_dst_cookie) == NULL) { 1242 dst_release(dst); 1243 sk->sk_rx_dst = NULL; 1244 } 1245 } 1246 1247 tcp_rcv_established(sk, skb, tcp_hdr(skb), skb->len); 1248 if (opt_skb) 1249 goto ipv6_pktoptions; 1250 return 0; 1251 } 1252 1253 if (skb->len < tcp_hdrlen(skb) || tcp_checksum_complete(skb)) 1254 goto csum_err; 1255 1256 if (sk->sk_state == TCP_LISTEN) { 1257 struct sock *nsk = tcp_v6_hnd_req(sk, skb); 1258 if (!nsk) 1259 goto discard; 1260 1261 /* 1262 * Queue it on the new socket if the new socket is active, 1263 * otherwise we just shortcircuit this and continue with 1264 * the new socket.. 1265 */ 1266 if (nsk != sk) { 1267 sock_rps_save_rxhash(nsk, skb); 1268 sk_mark_napi_id(sk, skb); 1269 if (tcp_child_process(sk, nsk, skb)) 1270 goto reset; 1271 if (opt_skb) 1272 __kfree_skb(opt_skb); 1273 return 0; 1274 } 1275 } else 1276 sock_rps_save_rxhash(sk, skb); 1277 1278 if (tcp_rcv_state_process(sk, skb, tcp_hdr(skb), skb->len)) 1279 goto reset; 1280 if (opt_skb) 1281 goto ipv6_pktoptions; 1282 return 0; 1283 1284 reset: 1285 tcp_v6_send_reset(sk, skb); 1286 discard: 1287 if (opt_skb) 1288 __kfree_skb(opt_skb); 1289 kfree_skb(skb); 1290 return 0; 1291 csum_err: 1292 TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_CSUMERRORS); 1293 TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_INERRS); 1294 goto discard; 1295 1296 1297 ipv6_pktoptions: 1298 /* Do you ask, what is it? 1299 1300 1. skb was enqueued by tcp. 1301 2. skb is added to tail of read queue, rather than out of order. 1302 3. socket is not in passive state. 1303 4. Finally, it really contains options, which user wants to receive. 1304 */ 1305 tp = tcp_sk(sk); 1306 if (TCP_SKB_CB(opt_skb)->end_seq == tp->rcv_nxt && 1307 !((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))) { 1308 if (np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo) 1309 np->mcast_oif = tcp_v6_iif(opt_skb); 1310 if (np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) 1311 np->mcast_hops = ipv6_hdr(opt_skb)->hop_limit; 1312 if (np->rxopt.bits.rxflow || np->rxopt.bits.rxtclass) 1313 np->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(opt_skb)); 1314 if (np->repflow) 1315 np->flow_label = ip6_flowlabel(ipv6_hdr(opt_skb)); 1316 if (ipv6_opt_accepted(sk, opt_skb, &TCP_SKB_CB(opt_skb)->header.h6)) { 1317 skb_set_owner_r(opt_skb, sk); 1318 opt_skb = xchg(&np->pktoptions, opt_skb); 1319 } else { 1320 __kfree_skb(opt_skb); 1321 opt_skb = xchg(&np->pktoptions, NULL); 1322 } 1323 } 1324 1325 kfree_skb(opt_skb); 1326 return 0; 1327 } 1328 1329 static void tcp_v6_fill_cb(struct sk_buff *skb, const struct ipv6hdr *hdr, 1330 const struct tcphdr *th) 1331 { 1332 /* This is tricky: we move IP6CB at its correct location into 1333 * TCP_SKB_CB(). It must be done after xfrm6_policy_check(), because 1334 * _decode_session6() uses IP6CB(). 1335 * barrier() makes sure compiler won't play aliasing games. 1336 */ 1337 memmove(&TCP_SKB_CB(skb)->header.h6, IP6CB(skb), 1338 sizeof(struct inet6_skb_parm)); 1339 barrier(); 1340 1341 TCP_SKB_CB(skb)->seq = ntohl(th->seq); 1342 TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin + 1343 skb->len - th->doff*4); 1344 TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq); 1345 TCP_SKB_CB(skb)->tcp_flags = tcp_flag_byte(th); 1346 TCP_SKB_CB(skb)->tcp_tw_isn = 0; 1347 TCP_SKB_CB(skb)->ip_dsfield = ipv6_get_dsfield(hdr); 1348 TCP_SKB_CB(skb)->sacked = 0; 1349 } 1350 1351 static void tcp_v6_restore_cb(struct sk_buff *skb) 1352 { 1353 /* We need to move header back to the beginning if xfrm6_policy_check() 1354 * and tcp_v6_fill_cb() are going to be called again. 1355 */ 1356 memmove(IP6CB(skb), &TCP_SKB_CB(skb)->header.h6, 1357 sizeof(struct inet6_skb_parm)); 1358 } 1359 1360 static int tcp_v6_rcv(struct sk_buff *skb) 1361 { 1362 const struct tcphdr *th; 1363 const struct ipv6hdr *hdr; 1364 struct sock *sk; 1365 int ret; 1366 struct net *net = dev_net(skb->dev); 1367 1368 if (skb->pkt_type != PACKET_HOST) 1369 goto discard_it; 1370 1371 /* 1372 * Count it even if it's bad. 1373 */ 1374 TCP_INC_STATS_BH(net, TCP_MIB_INSEGS); 1375 1376 if (!pskb_may_pull(skb, sizeof(struct tcphdr))) 1377 goto discard_it; 1378 1379 th = tcp_hdr(skb); 1380 1381 if (th->doff < sizeof(struct tcphdr)/4) 1382 goto bad_packet; 1383 if (!pskb_may_pull(skb, th->doff*4)) 1384 goto discard_it; 1385 1386 if (skb_checksum_init(skb, IPPROTO_TCP, ip6_compute_pseudo)) 1387 goto csum_error; 1388 1389 th = tcp_hdr(skb); 1390 hdr = ipv6_hdr(skb); 1391 1392 sk = __inet6_lookup_skb(&tcp_hashinfo, skb, th->source, th->dest, 1393 inet6_iif(skb)); 1394 if (!sk) 1395 goto no_tcp_socket; 1396 1397 process: 1398 if (sk->sk_state == TCP_TIME_WAIT) 1399 goto do_time_wait; 1400 1401 if (hdr->hop_limit < inet6_sk(sk)->min_hopcount) { 1402 NET_INC_STATS_BH(net, LINUX_MIB_TCPMINTTLDROP); 1403 goto discard_and_relse; 1404 } 1405 1406 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) 1407 goto discard_and_relse; 1408 1409 tcp_v6_fill_cb(skb, hdr, th); 1410 1411 #ifdef CONFIG_TCP_MD5SIG 1412 if (tcp_v6_inbound_md5_hash(sk, skb)) 1413 goto discard_and_relse; 1414 #endif 1415 1416 if (sk_filter(sk, skb)) 1417 goto discard_and_relse; 1418 1419 sk_incoming_cpu_update(sk); 1420 skb->dev = NULL; 1421 1422 bh_lock_sock_nested(sk); 1423 tcp_sk(sk)->segs_in += max_t(u16, 1, skb_shinfo(skb)->gso_segs); 1424 ret = 0; 1425 if (!sock_owned_by_user(sk)) { 1426 if (!tcp_prequeue(sk, skb)) 1427 ret = tcp_v6_do_rcv(sk, skb); 1428 } else if (unlikely(sk_add_backlog(sk, skb, 1429 sk->sk_rcvbuf + sk->sk_sndbuf))) { 1430 bh_unlock_sock(sk); 1431 NET_INC_STATS_BH(net, LINUX_MIB_TCPBACKLOGDROP); 1432 goto discard_and_relse; 1433 } 1434 bh_unlock_sock(sk); 1435 1436 sock_put(sk); 1437 return ret ? -1 : 0; 1438 1439 no_tcp_socket: 1440 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 1441 goto discard_it; 1442 1443 tcp_v6_fill_cb(skb, hdr, th); 1444 1445 if (skb->len < (th->doff<<2) || tcp_checksum_complete(skb)) { 1446 csum_error: 1447 TCP_INC_STATS_BH(net, TCP_MIB_CSUMERRORS); 1448 bad_packet: 1449 TCP_INC_STATS_BH(net, TCP_MIB_INERRS); 1450 } else { 1451 tcp_v6_send_reset(NULL, skb); 1452 } 1453 1454 discard_it: 1455 kfree_skb(skb); 1456 return 0; 1457 1458 discard_and_relse: 1459 sock_put(sk); 1460 goto discard_it; 1461 1462 do_time_wait: 1463 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) { 1464 inet_twsk_put(inet_twsk(sk)); 1465 goto discard_it; 1466 } 1467 1468 tcp_v6_fill_cb(skb, hdr, th); 1469 1470 if (skb->len < (th->doff<<2)) { 1471 inet_twsk_put(inet_twsk(sk)); 1472 goto bad_packet; 1473 } 1474 if (tcp_checksum_complete(skb)) { 1475 inet_twsk_put(inet_twsk(sk)); 1476 goto csum_error; 1477 } 1478 1479 switch (tcp_timewait_state_process(inet_twsk(sk), skb, th)) { 1480 case TCP_TW_SYN: 1481 { 1482 struct sock *sk2; 1483 1484 sk2 = inet6_lookup_listener(dev_net(skb->dev), &tcp_hashinfo, 1485 &ipv6_hdr(skb)->saddr, th->source, 1486 &ipv6_hdr(skb)->daddr, 1487 ntohs(th->dest), tcp_v6_iif(skb)); 1488 if (sk2) { 1489 struct inet_timewait_sock *tw = inet_twsk(sk); 1490 inet_twsk_deschedule(tw); 1491 inet_twsk_put(tw); 1492 sk = sk2; 1493 tcp_v6_restore_cb(skb); 1494 goto process; 1495 } 1496 /* Fall through to ACK */ 1497 } 1498 case TCP_TW_ACK: 1499 tcp_v6_timewait_ack(sk, skb); 1500 break; 1501 case TCP_TW_RST: 1502 tcp_v6_restore_cb(skb); 1503 goto no_tcp_socket; 1504 case TCP_TW_SUCCESS: 1505 ; 1506 } 1507 goto discard_it; 1508 } 1509 1510 static void tcp_v6_early_demux(struct sk_buff *skb) 1511 { 1512 const struct ipv6hdr *hdr; 1513 const struct tcphdr *th; 1514 struct sock *sk; 1515 1516 if (skb->pkt_type != PACKET_HOST) 1517 return; 1518 1519 if (!pskb_may_pull(skb, skb_transport_offset(skb) + sizeof(struct tcphdr))) 1520 return; 1521 1522 hdr = ipv6_hdr(skb); 1523 th = tcp_hdr(skb); 1524 1525 if (th->doff < sizeof(struct tcphdr) / 4) 1526 return; 1527 1528 /* Note : We use inet6_iif() here, not tcp_v6_iif() */ 1529 sk = __inet6_lookup_established(dev_net(skb->dev), &tcp_hashinfo, 1530 &hdr->saddr, th->source, 1531 &hdr->daddr, ntohs(th->dest), 1532 inet6_iif(skb)); 1533 if (sk) { 1534 skb->sk = sk; 1535 skb->destructor = sock_edemux; 1536 if (sk_fullsock(sk)) { 1537 struct dst_entry *dst = READ_ONCE(sk->sk_rx_dst); 1538 1539 if (dst) 1540 dst = dst_check(dst, inet6_sk(sk)->rx_dst_cookie); 1541 if (dst && 1542 inet_sk(sk)->rx_dst_ifindex == skb->skb_iif) 1543 skb_dst_set_noref(skb, dst); 1544 } 1545 } 1546 } 1547 1548 static struct timewait_sock_ops tcp6_timewait_sock_ops = { 1549 .twsk_obj_size = sizeof(struct tcp6_timewait_sock), 1550 .twsk_unique = tcp_twsk_unique, 1551 .twsk_destructor = tcp_twsk_destructor, 1552 }; 1553 1554 static const struct inet_connection_sock_af_ops ipv6_specific = { 1555 .queue_xmit = inet6_csk_xmit, 1556 .send_check = tcp_v6_send_check, 1557 .rebuild_header = inet6_sk_rebuild_header, 1558 .sk_rx_dst_set = inet6_sk_rx_dst_set, 1559 .conn_request = tcp_v6_conn_request, 1560 .syn_recv_sock = tcp_v6_syn_recv_sock, 1561 .net_header_len = sizeof(struct ipv6hdr), 1562 .net_frag_header_len = sizeof(struct frag_hdr), 1563 .setsockopt = ipv6_setsockopt, 1564 .getsockopt = ipv6_getsockopt, 1565 .addr2sockaddr = inet6_csk_addr2sockaddr, 1566 .sockaddr_len = sizeof(struct sockaddr_in6), 1567 .bind_conflict = inet6_csk_bind_conflict, 1568 #ifdef CONFIG_COMPAT 1569 .compat_setsockopt = compat_ipv6_setsockopt, 1570 .compat_getsockopt = compat_ipv6_getsockopt, 1571 #endif 1572 .mtu_reduced = tcp_v6_mtu_reduced, 1573 }; 1574 1575 #ifdef CONFIG_TCP_MD5SIG 1576 static const struct tcp_sock_af_ops tcp_sock_ipv6_specific = { 1577 .md5_lookup = tcp_v6_md5_lookup, 1578 .calc_md5_hash = tcp_v6_md5_hash_skb, 1579 .md5_parse = tcp_v6_parse_md5_keys, 1580 }; 1581 #endif 1582 1583 /* 1584 * TCP over IPv4 via INET6 API 1585 */ 1586 static const struct inet_connection_sock_af_ops ipv6_mapped = { 1587 .queue_xmit = ip_queue_xmit, 1588 .send_check = tcp_v4_send_check, 1589 .rebuild_header = inet_sk_rebuild_header, 1590 .sk_rx_dst_set = inet_sk_rx_dst_set, 1591 .conn_request = tcp_v6_conn_request, 1592 .syn_recv_sock = tcp_v6_syn_recv_sock, 1593 .net_header_len = sizeof(struct iphdr), 1594 .setsockopt = ipv6_setsockopt, 1595 .getsockopt = ipv6_getsockopt, 1596 .addr2sockaddr = inet6_csk_addr2sockaddr, 1597 .sockaddr_len = sizeof(struct sockaddr_in6), 1598 .bind_conflict = inet6_csk_bind_conflict, 1599 #ifdef CONFIG_COMPAT 1600 .compat_setsockopt = compat_ipv6_setsockopt, 1601 .compat_getsockopt = compat_ipv6_getsockopt, 1602 #endif 1603 .mtu_reduced = tcp_v4_mtu_reduced, 1604 }; 1605 1606 #ifdef CONFIG_TCP_MD5SIG 1607 static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific = { 1608 .md5_lookup = tcp_v4_md5_lookup, 1609 .calc_md5_hash = tcp_v4_md5_hash_skb, 1610 .md5_parse = tcp_v6_parse_md5_keys, 1611 }; 1612 #endif 1613 1614 /* NOTE: A lot of things set to zero explicitly by call to 1615 * sk_alloc() so need not be done here. 1616 */ 1617 static int tcp_v6_init_sock(struct sock *sk) 1618 { 1619 struct inet_connection_sock *icsk = inet_csk(sk); 1620 1621 tcp_init_sock(sk); 1622 1623 icsk->icsk_af_ops = &ipv6_specific; 1624 1625 #ifdef CONFIG_TCP_MD5SIG 1626 tcp_sk(sk)->af_specific = &tcp_sock_ipv6_specific; 1627 #endif 1628 1629 return 0; 1630 } 1631 1632 static void tcp_v6_destroy_sock(struct sock *sk) 1633 { 1634 tcp_v4_destroy_sock(sk); 1635 inet6_destroy_sock(sk); 1636 } 1637 1638 #ifdef CONFIG_PROC_FS 1639 /* Proc filesystem TCPv6 sock list dumping. */ 1640 static void get_openreq6(struct seq_file *seq, 1641 struct request_sock *req, int i, kuid_t uid) 1642 { 1643 long ttd = req->rsk_timer.expires - jiffies; 1644 const struct in6_addr *src = &inet_rsk(req)->ir_v6_loc_addr; 1645 const struct in6_addr *dest = &inet_rsk(req)->ir_v6_rmt_addr; 1646 1647 if (ttd < 0) 1648 ttd = 0; 1649 1650 seq_printf(seq, 1651 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1652 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %d %d %pK\n", 1653 i, 1654 src->s6_addr32[0], src->s6_addr32[1], 1655 src->s6_addr32[2], src->s6_addr32[3], 1656 inet_rsk(req)->ir_num, 1657 dest->s6_addr32[0], dest->s6_addr32[1], 1658 dest->s6_addr32[2], dest->s6_addr32[3], 1659 ntohs(inet_rsk(req)->ir_rmt_port), 1660 TCP_SYN_RECV, 1661 0, 0, /* could print option size, but that is af dependent. */ 1662 1, /* timers active (only the expire timer) */ 1663 jiffies_to_clock_t(ttd), 1664 req->num_timeout, 1665 from_kuid_munged(seq_user_ns(seq), uid), 1666 0, /* non standard timer */ 1667 0, /* open_requests have no inode */ 1668 0, req); 1669 } 1670 1671 static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i) 1672 { 1673 const struct in6_addr *dest, *src; 1674 __u16 destp, srcp; 1675 int timer_active; 1676 unsigned long timer_expires; 1677 const struct inet_sock *inet = inet_sk(sp); 1678 const struct tcp_sock *tp = tcp_sk(sp); 1679 const struct inet_connection_sock *icsk = inet_csk(sp); 1680 struct fastopen_queue *fastopenq = icsk->icsk_accept_queue.fastopenq; 1681 1682 dest = &sp->sk_v6_daddr; 1683 src = &sp->sk_v6_rcv_saddr; 1684 destp = ntohs(inet->inet_dport); 1685 srcp = ntohs(inet->inet_sport); 1686 1687 if (icsk->icsk_pending == ICSK_TIME_RETRANS) { 1688 timer_active = 1; 1689 timer_expires = icsk->icsk_timeout; 1690 } else if (icsk->icsk_pending == ICSK_TIME_PROBE0) { 1691 timer_active = 4; 1692 timer_expires = icsk->icsk_timeout; 1693 } else if (timer_pending(&sp->sk_timer)) { 1694 timer_active = 2; 1695 timer_expires = sp->sk_timer.expires; 1696 } else { 1697 timer_active = 0; 1698 timer_expires = jiffies; 1699 } 1700 1701 seq_printf(seq, 1702 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1703 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %lu %lu %u %u %d\n", 1704 i, 1705 src->s6_addr32[0], src->s6_addr32[1], 1706 src->s6_addr32[2], src->s6_addr32[3], srcp, 1707 dest->s6_addr32[0], dest->s6_addr32[1], 1708 dest->s6_addr32[2], dest->s6_addr32[3], destp, 1709 sp->sk_state, 1710 tp->write_seq-tp->snd_una, 1711 (sp->sk_state == TCP_LISTEN) ? sp->sk_ack_backlog : (tp->rcv_nxt - tp->copied_seq), 1712 timer_active, 1713 jiffies_delta_to_clock_t(timer_expires - jiffies), 1714 icsk->icsk_retransmits, 1715 from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)), 1716 icsk->icsk_probes_out, 1717 sock_i_ino(sp), 1718 atomic_read(&sp->sk_refcnt), sp, 1719 jiffies_to_clock_t(icsk->icsk_rto), 1720 jiffies_to_clock_t(icsk->icsk_ack.ato), 1721 (icsk->icsk_ack.quick << 1) | icsk->icsk_ack.pingpong, 1722 tp->snd_cwnd, 1723 sp->sk_state == TCP_LISTEN ? 1724 (fastopenq ? fastopenq->max_qlen : 0) : 1725 (tcp_in_initial_slowstart(tp) ? -1 : tp->snd_ssthresh) 1726 ); 1727 } 1728 1729 static void get_timewait6_sock(struct seq_file *seq, 1730 struct inet_timewait_sock *tw, int i) 1731 { 1732 long delta = tw->tw_timer.expires - jiffies; 1733 const struct in6_addr *dest, *src; 1734 __u16 destp, srcp; 1735 1736 dest = &tw->tw_v6_daddr; 1737 src = &tw->tw_v6_rcv_saddr; 1738 destp = ntohs(tw->tw_dport); 1739 srcp = ntohs(tw->tw_sport); 1740 1741 seq_printf(seq, 1742 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1743 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK\n", 1744 i, 1745 src->s6_addr32[0], src->s6_addr32[1], 1746 src->s6_addr32[2], src->s6_addr32[3], srcp, 1747 dest->s6_addr32[0], dest->s6_addr32[1], 1748 dest->s6_addr32[2], dest->s6_addr32[3], destp, 1749 tw->tw_substate, 0, 0, 1750 3, jiffies_delta_to_clock_t(delta), 0, 0, 0, 0, 1751 atomic_read(&tw->tw_refcnt), tw); 1752 } 1753 1754 static int tcp6_seq_show(struct seq_file *seq, void *v) 1755 { 1756 struct tcp_iter_state *st; 1757 struct sock *sk = v; 1758 1759 if (v == SEQ_START_TOKEN) { 1760 seq_puts(seq, 1761 " sl " 1762 "local_address " 1763 "remote_address " 1764 "st tx_queue rx_queue tr tm->when retrnsmt" 1765 " uid timeout inode\n"); 1766 goto out; 1767 } 1768 st = seq->private; 1769 1770 switch (st->state) { 1771 case TCP_SEQ_STATE_LISTENING: 1772 case TCP_SEQ_STATE_ESTABLISHED: 1773 if (sk->sk_state == TCP_TIME_WAIT) 1774 get_timewait6_sock(seq, v, st->num); 1775 else 1776 get_tcp6_sock(seq, v, st->num); 1777 break; 1778 case TCP_SEQ_STATE_OPENREQ: 1779 get_openreq6(seq, v, st->num, st->uid); 1780 break; 1781 } 1782 out: 1783 return 0; 1784 } 1785 1786 static const struct file_operations tcp6_afinfo_seq_fops = { 1787 .owner = THIS_MODULE, 1788 .open = tcp_seq_open, 1789 .read = seq_read, 1790 .llseek = seq_lseek, 1791 .release = seq_release_net 1792 }; 1793 1794 static struct tcp_seq_afinfo tcp6_seq_afinfo = { 1795 .name = "tcp6", 1796 .family = AF_INET6, 1797 .seq_fops = &tcp6_afinfo_seq_fops, 1798 .seq_ops = { 1799 .show = tcp6_seq_show, 1800 }, 1801 }; 1802 1803 int __net_init tcp6_proc_init(struct net *net) 1804 { 1805 return tcp_proc_register(net, &tcp6_seq_afinfo); 1806 } 1807 1808 void tcp6_proc_exit(struct net *net) 1809 { 1810 tcp_proc_unregister(net, &tcp6_seq_afinfo); 1811 } 1812 #endif 1813 1814 static void tcp_v6_clear_sk(struct sock *sk, int size) 1815 { 1816 struct inet_sock *inet = inet_sk(sk); 1817 1818 /* we do not want to clear pinet6 field, because of RCU lookups */ 1819 sk_prot_clear_nulls(sk, offsetof(struct inet_sock, pinet6)); 1820 1821 size -= offsetof(struct inet_sock, pinet6) + sizeof(inet->pinet6); 1822 memset(&inet->pinet6 + 1, 0, size); 1823 } 1824 1825 struct proto tcpv6_prot = { 1826 .name = "TCPv6", 1827 .owner = THIS_MODULE, 1828 .close = tcp_close, 1829 .connect = tcp_v6_connect, 1830 .disconnect = tcp_disconnect, 1831 .accept = inet_csk_accept, 1832 .ioctl = tcp_ioctl, 1833 .init = tcp_v6_init_sock, 1834 .destroy = tcp_v6_destroy_sock, 1835 .shutdown = tcp_shutdown, 1836 .setsockopt = tcp_setsockopt, 1837 .getsockopt = tcp_getsockopt, 1838 .recvmsg = tcp_recvmsg, 1839 .sendmsg = tcp_sendmsg, 1840 .sendpage = tcp_sendpage, 1841 .backlog_rcv = tcp_v6_do_rcv, 1842 .release_cb = tcp_release_cb, 1843 .hash = inet_hash, 1844 .unhash = inet_unhash, 1845 .get_port = inet_csk_get_port, 1846 .enter_memory_pressure = tcp_enter_memory_pressure, 1847 .stream_memory_free = tcp_stream_memory_free, 1848 .sockets_allocated = &tcp_sockets_allocated, 1849 .memory_allocated = &tcp_memory_allocated, 1850 .memory_pressure = &tcp_memory_pressure, 1851 .orphan_count = &tcp_orphan_count, 1852 .sysctl_mem = sysctl_tcp_mem, 1853 .sysctl_wmem = sysctl_tcp_wmem, 1854 .sysctl_rmem = sysctl_tcp_rmem, 1855 .max_header = MAX_TCP_HEADER, 1856 .obj_size = sizeof(struct tcp6_sock), 1857 .slab_flags = SLAB_DESTROY_BY_RCU, 1858 .twsk_prot = &tcp6_timewait_sock_ops, 1859 .rsk_prot = &tcp6_request_sock_ops, 1860 .h.hashinfo = &tcp_hashinfo, 1861 .no_autobind = true, 1862 #ifdef CONFIG_COMPAT 1863 .compat_setsockopt = compat_tcp_setsockopt, 1864 .compat_getsockopt = compat_tcp_getsockopt, 1865 #endif 1866 #ifdef CONFIG_MEMCG_KMEM 1867 .proto_cgroup = tcp_proto_cgroup, 1868 #endif 1869 .clear_sk = tcp_v6_clear_sk, 1870 }; 1871 1872 static const struct inet6_protocol tcpv6_protocol = { 1873 .early_demux = tcp_v6_early_demux, 1874 .handler = tcp_v6_rcv, 1875 .err_handler = tcp_v6_err, 1876 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 1877 }; 1878 1879 static struct inet_protosw tcpv6_protosw = { 1880 .type = SOCK_STREAM, 1881 .protocol = IPPROTO_TCP, 1882 .prot = &tcpv6_prot, 1883 .ops = &inet6_stream_ops, 1884 .flags = INET_PROTOSW_PERMANENT | 1885 INET_PROTOSW_ICSK, 1886 }; 1887 1888 static int __net_init tcpv6_net_init(struct net *net) 1889 { 1890 return inet_ctl_sock_create(&net->ipv6.tcp_sk, PF_INET6, 1891 SOCK_RAW, IPPROTO_TCP, net); 1892 } 1893 1894 static void __net_exit tcpv6_net_exit(struct net *net) 1895 { 1896 inet_ctl_sock_destroy(net->ipv6.tcp_sk); 1897 } 1898 1899 static void __net_exit tcpv6_net_exit_batch(struct list_head *net_exit_list) 1900 { 1901 inet_twsk_purge(&tcp_hashinfo, &tcp_death_row, AF_INET6); 1902 } 1903 1904 static struct pernet_operations tcpv6_net_ops = { 1905 .init = tcpv6_net_init, 1906 .exit = tcpv6_net_exit, 1907 .exit_batch = tcpv6_net_exit_batch, 1908 }; 1909 1910 int __init tcpv6_init(void) 1911 { 1912 int ret; 1913 1914 ret = inet6_add_protocol(&tcpv6_protocol, IPPROTO_TCP); 1915 if (ret) 1916 goto out; 1917 1918 /* register inet6 protocol */ 1919 ret = inet6_register_protosw(&tcpv6_protosw); 1920 if (ret) 1921 goto out_tcpv6_protocol; 1922 1923 ret = register_pernet_subsys(&tcpv6_net_ops); 1924 if (ret) 1925 goto out_tcpv6_protosw; 1926 out: 1927 return ret; 1928 1929 out_tcpv6_protosw: 1930 inet6_unregister_protosw(&tcpv6_protosw); 1931 out_tcpv6_protocol: 1932 inet6_del_protocol(&tcpv6_protocol, IPPROTO_TCP); 1933 goto out; 1934 } 1935 1936 void tcpv6_exit(void) 1937 { 1938 unregister_pernet_subsys(&tcpv6_net_ops); 1939 inet6_unregister_protosw(&tcpv6_protosw); 1940 inet6_del_protocol(&tcpv6_protocol, IPPROTO_TCP); 1941 } 1942