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(const struct sock *sk, struct sk_buff *skb); 74 static void tcp_v6_reqsk_send_ack(const 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(const 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 flowi6 fl6; 124 struct dst_entry *dst; 125 int addr_type; 126 int err; 127 128 if (addr_len < SIN6_LEN_RFC2133) 129 return -EINVAL; 130 131 if (usin->sin6_family != AF_INET6) 132 return -EAFNOSUPPORT; 133 134 memset(&fl6, 0, sizeof(fl6)); 135 136 if (np->sndflow) { 137 fl6.flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK; 138 IP6_ECN_flow_init(fl6.flowlabel); 139 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) { 140 struct ip6_flowlabel *flowlabel; 141 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel); 142 if (!flowlabel) 143 return -EINVAL; 144 fl6_sock_release(flowlabel); 145 } 146 } 147 148 /* 149 * connect() to INADDR_ANY means loopback (BSD'ism). 150 */ 151 152 if (ipv6_addr_any(&usin->sin6_addr)) 153 usin->sin6_addr.s6_addr[15] = 0x1; 154 155 addr_type = ipv6_addr_type(&usin->sin6_addr); 156 157 if (addr_type & IPV6_ADDR_MULTICAST) 158 return -ENETUNREACH; 159 160 if (addr_type&IPV6_ADDR_LINKLOCAL) { 161 if (addr_len >= sizeof(struct sockaddr_in6) && 162 usin->sin6_scope_id) { 163 /* If interface is set while binding, indices 164 * must coincide. 165 */ 166 if (sk->sk_bound_dev_if && 167 sk->sk_bound_dev_if != usin->sin6_scope_id) 168 return -EINVAL; 169 170 sk->sk_bound_dev_if = usin->sin6_scope_id; 171 } 172 173 /* Connect to link-local address requires an interface */ 174 if (!sk->sk_bound_dev_if) 175 return -EINVAL; 176 } 177 178 if (tp->rx_opt.ts_recent_stamp && 179 !ipv6_addr_equal(&sk->sk_v6_daddr, &usin->sin6_addr)) { 180 tp->rx_opt.ts_recent = 0; 181 tp->rx_opt.ts_recent_stamp = 0; 182 tp->write_seq = 0; 183 } 184 185 sk->sk_v6_daddr = usin->sin6_addr; 186 np->flow_label = fl6.flowlabel; 187 188 /* 189 * TCP over IPv4 190 */ 191 192 if (addr_type == IPV6_ADDR_MAPPED) { 193 u32 exthdrlen = icsk->icsk_ext_hdr_len; 194 struct sockaddr_in sin; 195 196 SOCK_DEBUG(sk, "connect: ipv4 mapped\n"); 197 198 if (__ipv6_only_sock(sk)) 199 return -ENETUNREACH; 200 201 sin.sin_family = AF_INET; 202 sin.sin_port = usin->sin6_port; 203 sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3]; 204 205 icsk->icsk_af_ops = &ipv6_mapped; 206 sk->sk_backlog_rcv = tcp_v4_do_rcv; 207 #ifdef CONFIG_TCP_MD5SIG 208 tp->af_specific = &tcp_sock_ipv6_mapped_specific; 209 #endif 210 211 err = tcp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin)); 212 213 if (err) { 214 icsk->icsk_ext_hdr_len = exthdrlen; 215 icsk->icsk_af_ops = &ipv6_specific; 216 sk->sk_backlog_rcv = tcp_v6_do_rcv; 217 #ifdef CONFIG_TCP_MD5SIG 218 tp->af_specific = &tcp_sock_ipv6_specific; 219 #endif 220 goto failure; 221 } 222 np->saddr = sk->sk_v6_rcv_saddr; 223 224 return err; 225 } 226 227 if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) 228 saddr = &sk->sk_v6_rcv_saddr; 229 230 fl6.flowi6_proto = IPPROTO_TCP; 231 fl6.daddr = sk->sk_v6_daddr; 232 fl6.saddr = saddr ? *saddr : np->saddr; 233 fl6.flowi6_oif = sk->sk_bound_dev_if; 234 fl6.flowi6_mark = sk->sk_mark; 235 fl6.fl6_dport = usin->sin6_port; 236 fl6.fl6_sport = inet->inet_sport; 237 238 final_p = fl6_update_dst(&fl6, np->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 (np->opt) 267 icsk->icsk_ext_hdr_len = (np->opt->opt_flen + 268 np->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 err = ip6_xmit(sk, skb, fl6, np->opt, np->tclass); 465 err = net_xmit_eval(err); 466 } 467 468 done: 469 return err; 470 } 471 472 473 static void tcp_v6_reqsk_destructor(struct request_sock *req) 474 { 475 kfree_skb(inet_rsk(req)->pktopts); 476 } 477 478 #ifdef CONFIG_TCP_MD5SIG 479 static struct tcp_md5sig_key *tcp_v6_md5_do_lookup(const struct sock *sk, 480 const struct in6_addr *addr) 481 { 482 return tcp_md5_do_lookup(sk, (union tcp_md5_addr *)addr, AF_INET6); 483 } 484 485 static struct tcp_md5sig_key *tcp_v6_md5_lookup(const struct sock *sk, 486 const struct sock *addr_sk) 487 { 488 return tcp_v6_md5_do_lookup(sk, &addr_sk->sk_v6_daddr); 489 } 490 491 static int tcp_v6_parse_md5_keys(struct sock *sk, char __user *optval, 492 int optlen) 493 { 494 struct tcp_md5sig cmd; 495 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&cmd.tcpm_addr; 496 497 if (optlen < sizeof(cmd)) 498 return -EINVAL; 499 500 if (copy_from_user(&cmd, optval, sizeof(cmd))) 501 return -EFAULT; 502 503 if (sin6->sin6_family != AF_INET6) 504 return -EINVAL; 505 506 if (!cmd.tcpm_keylen) { 507 if (ipv6_addr_v4mapped(&sin6->sin6_addr)) 508 return tcp_md5_do_del(sk, (union tcp_md5_addr *)&sin6->sin6_addr.s6_addr32[3], 509 AF_INET); 510 return tcp_md5_do_del(sk, (union tcp_md5_addr *)&sin6->sin6_addr, 511 AF_INET6); 512 } 513 514 if (cmd.tcpm_keylen > TCP_MD5SIG_MAXKEYLEN) 515 return -EINVAL; 516 517 if (ipv6_addr_v4mapped(&sin6->sin6_addr)) 518 return tcp_md5_do_add(sk, (union tcp_md5_addr *)&sin6->sin6_addr.s6_addr32[3], 519 AF_INET, cmd.tcpm_key, cmd.tcpm_keylen, GFP_KERNEL); 520 521 return tcp_md5_do_add(sk, (union tcp_md5_addr *)&sin6->sin6_addr, 522 AF_INET6, cmd.tcpm_key, cmd.tcpm_keylen, GFP_KERNEL); 523 } 524 525 static int tcp_v6_md5_hash_pseudoheader(struct tcp_md5sig_pool *hp, 526 const struct in6_addr *daddr, 527 const struct in6_addr *saddr, int nbytes) 528 { 529 struct tcp6_pseudohdr *bp; 530 struct scatterlist sg; 531 532 bp = &hp->md5_blk.ip6; 533 /* 1. TCP pseudo-header (RFC2460) */ 534 bp->saddr = *saddr; 535 bp->daddr = *daddr; 536 bp->protocol = cpu_to_be32(IPPROTO_TCP); 537 bp->len = cpu_to_be32(nbytes); 538 539 sg_init_one(&sg, bp, sizeof(*bp)); 540 return crypto_hash_update(&hp->md5_desc, &sg, sizeof(*bp)); 541 } 542 543 static int tcp_v6_md5_hash_hdr(char *md5_hash, struct tcp_md5sig_key *key, 544 const struct in6_addr *daddr, struct in6_addr *saddr, 545 const struct tcphdr *th) 546 { 547 struct tcp_md5sig_pool *hp; 548 struct hash_desc *desc; 549 550 hp = tcp_get_md5sig_pool(); 551 if (!hp) 552 goto clear_hash_noput; 553 desc = &hp->md5_desc; 554 555 if (crypto_hash_init(desc)) 556 goto clear_hash; 557 if (tcp_v6_md5_hash_pseudoheader(hp, daddr, saddr, th->doff << 2)) 558 goto clear_hash; 559 if (tcp_md5_hash_header(hp, th)) 560 goto clear_hash; 561 if (tcp_md5_hash_key(hp, key)) 562 goto clear_hash; 563 if (crypto_hash_final(desc, md5_hash)) 564 goto clear_hash; 565 566 tcp_put_md5sig_pool(); 567 return 0; 568 569 clear_hash: 570 tcp_put_md5sig_pool(); 571 clear_hash_noput: 572 memset(md5_hash, 0, 16); 573 return 1; 574 } 575 576 static int tcp_v6_md5_hash_skb(char *md5_hash, 577 const struct tcp_md5sig_key *key, 578 const struct sock *sk, 579 const struct sk_buff *skb) 580 { 581 const struct in6_addr *saddr, *daddr; 582 struct tcp_md5sig_pool *hp; 583 struct hash_desc *desc; 584 const struct tcphdr *th = tcp_hdr(skb); 585 586 if (sk) { /* valid for establish/request sockets */ 587 saddr = &sk->sk_v6_rcv_saddr; 588 daddr = &sk->sk_v6_daddr; 589 } else { 590 const struct ipv6hdr *ip6h = ipv6_hdr(skb); 591 saddr = &ip6h->saddr; 592 daddr = &ip6h->daddr; 593 } 594 595 hp = tcp_get_md5sig_pool(); 596 if (!hp) 597 goto clear_hash_noput; 598 desc = &hp->md5_desc; 599 600 if (crypto_hash_init(desc)) 601 goto clear_hash; 602 603 if (tcp_v6_md5_hash_pseudoheader(hp, daddr, saddr, skb->len)) 604 goto clear_hash; 605 if (tcp_md5_hash_header(hp, th)) 606 goto clear_hash; 607 if (tcp_md5_hash_skb_data(hp, skb, th->doff << 2)) 608 goto clear_hash; 609 if (tcp_md5_hash_key(hp, key)) 610 goto clear_hash; 611 if (crypto_hash_final(desc, md5_hash)) 612 goto clear_hash; 613 614 tcp_put_md5sig_pool(); 615 return 0; 616 617 clear_hash: 618 tcp_put_md5sig_pool(); 619 clear_hash_noput: 620 memset(md5_hash, 0, 16); 621 return 1; 622 } 623 624 #endif 625 626 static bool tcp_v6_inbound_md5_hash(const struct sock *sk, 627 const struct sk_buff *skb) 628 { 629 #ifdef CONFIG_TCP_MD5SIG 630 const __u8 *hash_location = NULL; 631 struct tcp_md5sig_key *hash_expected; 632 const struct ipv6hdr *ip6h = ipv6_hdr(skb); 633 const struct tcphdr *th = tcp_hdr(skb); 634 int genhash; 635 u8 newhash[16]; 636 637 hash_expected = tcp_v6_md5_do_lookup(sk, &ip6h->saddr); 638 hash_location = tcp_parse_md5sig_option(th); 639 640 /* We've parsed the options - do we have a hash? */ 641 if (!hash_expected && !hash_location) 642 return false; 643 644 if (hash_expected && !hash_location) { 645 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND); 646 return true; 647 } 648 649 if (!hash_expected && hash_location) { 650 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED); 651 return true; 652 } 653 654 /* check the signature */ 655 genhash = tcp_v6_md5_hash_skb(newhash, 656 hash_expected, 657 NULL, skb); 658 659 if (genhash || memcmp(hash_location, newhash, 16) != 0) { 660 net_info_ratelimited("MD5 Hash %s for [%pI6c]:%u->[%pI6c]:%u\n", 661 genhash ? "failed" : "mismatch", 662 &ip6h->saddr, ntohs(th->source), 663 &ip6h->daddr, ntohs(th->dest)); 664 return true; 665 } 666 #endif 667 return false; 668 } 669 670 static void tcp_v6_init_req(struct request_sock *req, 671 const struct sock *sk_listener, 672 struct sk_buff *skb) 673 { 674 struct inet_request_sock *ireq = inet_rsk(req); 675 const struct ipv6_pinfo *np = inet6_sk(sk_listener); 676 677 ireq->ir_v6_rmt_addr = ipv6_hdr(skb)->saddr; 678 ireq->ir_v6_loc_addr = ipv6_hdr(skb)->daddr; 679 680 /* So that link locals have meaning */ 681 if (!sk_listener->sk_bound_dev_if && 682 ipv6_addr_type(&ireq->ir_v6_rmt_addr) & IPV6_ADDR_LINKLOCAL) 683 ireq->ir_iif = tcp_v6_iif(skb); 684 685 if (!TCP_SKB_CB(skb)->tcp_tw_isn && 686 (ipv6_opt_accepted(sk_listener, skb, &TCP_SKB_CB(skb)->header.h6) || 687 np->rxopt.bits.rxinfo || 688 np->rxopt.bits.rxoinfo || np->rxopt.bits.rxhlim || 689 np->rxopt.bits.rxohlim || np->repflow)) { 690 atomic_inc(&skb->users); 691 ireq->pktopts = skb; 692 } 693 } 694 695 static struct dst_entry *tcp_v6_route_req(const struct sock *sk, 696 struct flowi *fl, 697 const struct request_sock *req, 698 bool *strict) 699 { 700 if (strict) 701 *strict = true; 702 return inet6_csk_route_req(sk, &fl->u.ip6, req, IPPROTO_TCP); 703 } 704 705 struct request_sock_ops tcp6_request_sock_ops __read_mostly = { 706 .family = AF_INET6, 707 .obj_size = sizeof(struct tcp6_request_sock), 708 .rtx_syn_ack = tcp_rtx_synack, 709 .send_ack = tcp_v6_reqsk_send_ack, 710 .destructor = tcp_v6_reqsk_destructor, 711 .send_reset = tcp_v6_send_reset, 712 .syn_ack_timeout = tcp_syn_ack_timeout, 713 }; 714 715 static const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops = { 716 .mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - 717 sizeof(struct ipv6hdr), 718 #ifdef CONFIG_TCP_MD5SIG 719 .req_md5_lookup = tcp_v6_md5_lookup, 720 .calc_md5_hash = tcp_v6_md5_hash_skb, 721 #endif 722 .init_req = tcp_v6_init_req, 723 #ifdef CONFIG_SYN_COOKIES 724 .cookie_init_seq = cookie_v6_init_sequence, 725 #endif 726 .route_req = tcp_v6_route_req, 727 .init_seq = tcp_v6_init_sequence, 728 .send_synack = tcp_v6_send_synack, 729 }; 730 731 static void tcp_v6_send_response(const struct sock *sk, struct sk_buff *skb, u32 seq, 732 u32 ack, u32 win, u32 tsval, u32 tsecr, 733 int oif, struct tcp_md5sig_key *key, int rst, 734 u8 tclass, u32 label) 735 { 736 const struct tcphdr *th = tcp_hdr(skb); 737 struct tcphdr *t1; 738 struct sk_buff *buff; 739 struct flowi6 fl6; 740 struct net *net = sk ? sock_net(sk) : dev_net(skb_dst(skb)->dev); 741 struct sock *ctl_sk = net->ipv6.tcp_sk; 742 unsigned int tot_len = sizeof(struct tcphdr); 743 struct dst_entry *dst; 744 __be32 *topt; 745 746 if (tsecr) 747 tot_len += TCPOLEN_TSTAMP_ALIGNED; 748 #ifdef CONFIG_TCP_MD5SIG 749 if (key) 750 tot_len += TCPOLEN_MD5SIG_ALIGNED; 751 #endif 752 753 buff = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + tot_len, 754 GFP_ATOMIC); 755 if (!buff) 756 return; 757 758 skb_reserve(buff, MAX_HEADER + sizeof(struct ipv6hdr) + tot_len); 759 760 t1 = (struct tcphdr *) skb_push(buff, tot_len); 761 skb_reset_transport_header(buff); 762 763 /* Swap the send and the receive. */ 764 memset(t1, 0, sizeof(*t1)); 765 t1->dest = th->source; 766 t1->source = th->dest; 767 t1->doff = tot_len / 4; 768 t1->seq = htonl(seq); 769 t1->ack_seq = htonl(ack); 770 t1->ack = !rst || !th->ack; 771 t1->rst = rst; 772 t1->window = htons(win); 773 774 topt = (__be32 *)(t1 + 1); 775 776 if (tsecr) { 777 *topt++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | 778 (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP); 779 *topt++ = htonl(tsval); 780 *topt++ = htonl(tsecr); 781 } 782 783 #ifdef CONFIG_TCP_MD5SIG 784 if (key) { 785 *topt++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | 786 (TCPOPT_MD5SIG << 8) | TCPOLEN_MD5SIG); 787 tcp_v6_md5_hash_hdr((__u8 *)topt, key, 788 &ipv6_hdr(skb)->saddr, 789 &ipv6_hdr(skb)->daddr, t1); 790 } 791 #endif 792 793 memset(&fl6, 0, sizeof(fl6)); 794 fl6.daddr = ipv6_hdr(skb)->saddr; 795 fl6.saddr = ipv6_hdr(skb)->daddr; 796 fl6.flowlabel = label; 797 798 buff->ip_summed = CHECKSUM_PARTIAL; 799 buff->csum = 0; 800 801 __tcp_v6_send_check(buff, &fl6.saddr, &fl6.daddr); 802 803 fl6.flowi6_proto = IPPROTO_TCP; 804 if (rt6_need_strict(&fl6.daddr) && !oif) 805 fl6.flowi6_oif = tcp_v6_iif(skb); 806 else 807 fl6.flowi6_oif = oif; 808 fl6.flowi6_mark = IP6_REPLY_MARK(net, skb->mark); 809 fl6.fl6_dport = t1->dest; 810 fl6.fl6_sport = t1->source; 811 security_skb_classify_flow(skb, flowi6_to_flowi(&fl6)); 812 813 /* Pass a socket to ip6_dst_lookup either it is for RST 814 * Underlying function will use this to retrieve the network 815 * namespace 816 */ 817 dst = ip6_dst_lookup_flow(ctl_sk, &fl6, NULL); 818 if (!IS_ERR(dst)) { 819 skb_dst_set(buff, dst); 820 ip6_xmit(ctl_sk, buff, &fl6, NULL, tclass); 821 TCP_INC_STATS_BH(net, TCP_MIB_OUTSEGS); 822 if (rst) 823 TCP_INC_STATS_BH(net, TCP_MIB_OUTRSTS); 824 return; 825 } 826 827 kfree_skb(buff); 828 } 829 830 static void tcp_v6_send_reset(const struct sock *sk, struct sk_buff *skb) 831 { 832 const struct tcphdr *th = tcp_hdr(skb); 833 u32 seq = 0, ack_seq = 0; 834 struct tcp_md5sig_key *key = NULL; 835 #ifdef CONFIG_TCP_MD5SIG 836 const __u8 *hash_location = NULL; 837 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 838 unsigned char newhash[16]; 839 int genhash; 840 struct sock *sk1 = NULL; 841 #endif 842 int oif; 843 844 if (th->rst) 845 return; 846 847 /* If sk not NULL, it means we did a successful lookup and incoming 848 * route had to be correct. prequeue might have dropped our dst. 849 */ 850 if (!sk && !ipv6_unicast_destination(skb)) 851 return; 852 853 #ifdef CONFIG_TCP_MD5SIG 854 hash_location = tcp_parse_md5sig_option(th); 855 if (!sk && hash_location) { 856 /* 857 * active side is lost. Try to find listening socket through 858 * source port, and then find md5 key through listening socket. 859 * we are not loose security here: 860 * Incoming packet is checked with md5 hash with finding key, 861 * no RST generated if md5 hash doesn't match. 862 */ 863 sk1 = inet6_lookup_listener(dev_net(skb_dst(skb)->dev), 864 &tcp_hashinfo, &ipv6h->saddr, 865 th->source, &ipv6h->daddr, 866 ntohs(th->source), tcp_v6_iif(skb)); 867 if (!sk1) 868 return; 869 870 rcu_read_lock(); 871 key = tcp_v6_md5_do_lookup(sk1, &ipv6h->saddr); 872 if (!key) 873 goto release_sk1; 874 875 genhash = tcp_v6_md5_hash_skb(newhash, key, NULL, skb); 876 if (genhash || memcmp(hash_location, newhash, 16) != 0) 877 goto release_sk1; 878 } else { 879 key = sk ? tcp_v6_md5_do_lookup(sk, &ipv6h->saddr) : NULL; 880 } 881 #endif 882 883 if (th->ack) 884 seq = ntohl(th->ack_seq); 885 else 886 ack_seq = ntohl(th->seq) + th->syn + th->fin + skb->len - 887 (th->doff << 2); 888 889 oif = sk ? sk->sk_bound_dev_if : 0; 890 tcp_v6_send_response(sk, skb, seq, ack_seq, 0, 0, 0, oif, key, 1, 0, 0); 891 892 #ifdef CONFIG_TCP_MD5SIG 893 release_sk1: 894 if (sk1) { 895 rcu_read_unlock(); 896 sock_put(sk1); 897 } 898 #endif 899 } 900 901 static void tcp_v6_send_ack(const struct sock *sk, struct sk_buff *skb, u32 seq, 902 u32 ack, u32 win, u32 tsval, u32 tsecr, int oif, 903 struct tcp_md5sig_key *key, u8 tclass, 904 u32 label) 905 { 906 tcp_v6_send_response(sk, skb, seq, ack, win, tsval, tsecr, oif, key, 0, 907 tclass, label); 908 } 909 910 static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb) 911 { 912 struct inet_timewait_sock *tw = inet_twsk(sk); 913 struct tcp_timewait_sock *tcptw = tcp_twsk(sk); 914 915 tcp_v6_send_ack(sk, skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt, 916 tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale, 917 tcp_time_stamp + tcptw->tw_ts_offset, 918 tcptw->tw_ts_recent, tw->tw_bound_dev_if, tcp_twsk_md5_key(tcptw), 919 tw->tw_tclass, cpu_to_be32(tw->tw_flowlabel)); 920 921 inet_twsk_put(tw); 922 } 923 924 static void tcp_v6_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, 925 struct request_sock *req) 926 { 927 /* sk->sk_state == TCP_LISTEN -> for regular TCP_SYN_RECV 928 * sk->sk_state == TCP_SYN_RECV -> for Fast Open. 929 */ 930 tcp_v6_send_ack(sk, skb, (sk->sk_state == TCP_LISTEN) ? 931 tcp_rsk(req)->snt_isn + 1 : tcp_sk(sk)->snd_nxt, 932 tcp_rsk(req)->rcv_nxt, req->rsk_rcv_wnd, 933 tcp_time_stamp, req->ts_recent, sk->sk_bound_dev_if, 934 tcp_v6_md5_do_lookup(sk, &ipv6_hdr(skb)->daddr), 935 0, 0); 936 } 937 938 939 static struct sock *tcp_v6_cookie_check(struct sock *sk, struct sk_buff *skb) 940 { 941 #ifdef CONFIG_SYN_COOKIES 942 const struct tcphdr *th = tcp_hdr(skb); 943 944 if (!th->syn) 945 sk = cookie_v6_check(sk, skb); 946 #endif 947 return sk; 948 } 949 950 static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb) 951 { 952 if (skb->protocol == htons(ETH_P_IP)) 953 return tcp_v4_conn_request(sk, skb); 954 955 if (!ipv6_unicast_destination(skb)) 956 goto drop; 957 958 return tcp_conn_request(&tcp6_request_sock_ops, 959 &tcp_request_sock_ipv6_ops, sk, skb); 960 961 drop: 962 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS); 963 return 0; /* don't send reset */ 964 } 965 966 static struct sock *tcp_v6_syn_recv_sock(const struct sock *sk, struct sk_buff *skb, 967 struct request_sock *req, 968 struct dst_entry *dst, 969 struct request_sock *req_unhash, 970 bool *own_req) 971 { 972 struct inet_request_sock *ireq; 973 struct ipv6_pinfo *newnp; 974 const struct ipv6_pinfo *np = inet6_sk(sk); 975 struct tcp6_sock *newtcp6sk; 976 struct inet_sock *newinet; 977 struct tcp_sock *newtp; 978 struct sock *newsk; 979 #ifdef CONFIG_TCP_MD5SIG 980 struct tcp_md5sig_key *key; 981 #endif 982 struct flowi6 fl6; 983 984 if (skb->protocol == htons(ETH_P_IP)) { 985 /* 986 * v6 mapped 987 */ 988 989 newsk = tcp_v4_syn_recv_sock(sk, skb, req, dst, 990 req_unhash, own_req); 991 992 if (!newsk) 993 return NULL; 994 995 newtcp6sk = (struct tcp6_sock *)newsk; 996 inet_sk(newsk)->pinet6 = &newtcp6sk->inet6; 997 998 newinet = inet_sk(newsk); 999 newnp = inet6_sk(newsk); 1000 newtp = tcp_sk(newsk); 1001 1002 memcpy(newnp, np, sizeof(struct ipv6_pinfo)); 1003 1004 newnp->saddr = newsk->sk_v6_rcv_saddr; 1005 1006 inet_csk(newsk)->icsk_af_ops = &ipv6_mapped; 1007 newsk->sk_backlog_rcv = tcp_v4_do_rcv; 1008 #ifdef CONFIG_TCP_MD5SIG 1009 newtp->af_specific = &tcp_sock_ipv6_mapped_specific; 1010 #endif 1011 1012 newnp->ipv6_ac_list = NULL; 1013 newnp->ipv6_fl_list = NULL; 1014 newnp->pktoptions = NULL; 1015 newnp->opt = NULL; 1016 newnp->mcast_oif = tcp_v6_iif(skb); 1017 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit; 1018 newnp->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(skb)); 1019 if (np->repflow) 1020 newnp->flow_label = ip6_flowlabel(ipv6_hdr(skb)); 1021 1022 /* 1023 * No need to charge this sock to the relevant IPv6 refcnt debug socks count 1024 * here, tcp_create_openreq_child now does this for us, see the comment in 1025 * that function for the gory details. -acme 1026 */ 1027 1028 /* It is tricky place. Until this moment IPv4 tcp 1029 worked with IPv6 icsk.icsk_af_ops. 1030 Sync it now. 1031 */ 1032 tcp_sync_mss(newsk, inet_csk(newsk)->icsk_pmtu_cookie); 1033 1034 return newsk; 1035 } 1036 1037 ireq = inet_rsk(req); 1038 1039 if (sk_acceptq_is_full(sk)) 1040 goto out_overflow; 1041 1042 if (!dst) { 1043 dst = inet6_csk_route_req(sk, &fl6, req, IPPROTO_TCP); 1044 if (!dst) 1045 goto out; 1046 } 1047 1048 newsk = tcp_create_openreq_child(sk, req, skb); 1049 if (!newsk) 1050 goto out_nonewsk; 1051 1052 /* 1053 * No need to charge this sock to the relevant IPv6 refcnt debug socks 1054 * count here, tcp_create_openreq_child now does this for us, see the 1055 * comment in that function for the gory details. -acme 1056 */ 1057 1058 newsk->sk_gso_type = SKB_GSO_TCPV6; 1059 __ip6_dst_store(newsk, dst, NULL, NULL); 1060 inet6_sk_rx_dst_set(newsk, skb); 1061 1062 newtcp6sk = (struct tcp6_sock *)newsk; 1063 inet_sk(newsk)->pinet6 = &newtcp6sk->inet6; 1064 1065 newtp = tcp_sk(newsk); 1066 newinet = inet_sk(newsk); 1067 newnp = inet6_sk(newsk); 1068 1069 memcpy(newnp, np, sizeof(struct ipv6_pinfo)); 1070 1071 newsk->sk_v6_daddr = ireq->ir_v6_rmt_addr; 1072 newnp->saddr = ireq->ir_v6_loc_addr; 1073 newsk->sk_v6_rcv_saddr = ireq->ir_v6_loc_addr; 1074 newsk->sk_bound_dev_if = ireq->ir_iif; 1075 1076 /* Now IPv6 options... 1077 1078 First: no IPv4 options. 1079 */ 1080 newinet->inet_opt = NULL; 1081 newnp->ipv6_ac_list = NULL; 1082 newnp->ipv6_fl_list = NULL; 1083 1084 /* Clone RX bits */ 1085 newnp->rxopt.all = np->rxopt.all; 1086 1087 newnp->pktoptions = NULL; 1088 newnp->opt = NULL; 1089 newnp->mcast_oif = tcp_v6_iif(skb); 1090 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit; 1091 newnp->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(skb)); 1092 if (np->repflow) 1093 newnp->flow_label = ip6_flowlabel(ipv6_hdr(skb)); 1094 1095 /* Clone native IPv6 options from listening socket (if any) 1096 1097 Yes, keeping reference count would be much more clever, 1098 but we make one more one thing there: reattach optmem 1099 to newsk. 1100 */ 1101 if (np->opt) 1102 newnp->opt = ipv6_dup_options(newsk, np->opt); 1103 1104 inet_csk(newsk)->icsk_ext_hdr_len = 0; 1105 if (newnp->opt) 1106 inet_csk(newsk)->icsk_ext_hdr_len = (newnp->opt->opt_nflen + 1107 newnp->opt->opt_flen); 1108 1109 tcp_ca_openreq_child(newsk, dst); 1110 1111 tcp_sync_mss(newsk, dst_mtu(dst)); 1112 newtp->advmss = dst_metric_advmss(dst); 1113 if (tcp_sk(sk)->rx_opt.user_mss && 1114 tcp_sk(sk)->rx_opt.user_mss < newtp->advmss) 1115 newtp->advmss = tcp_sk(sk)->rx_opt.user_mss; 1116 1117 tcp_initialize_rcv_mss(newsk); 1118 1119 newinet->inet_daddr = newinet->inet_saddr = LOOPBACK4_IPV6; 1120 newinet->inet_rcv_saddr = LOOPBACK4_IPV6; 1121 1122 #ifdef CONFIG_TCP_MD5SIG 1123 /* Copy over the MD5 key from the original socket */ 1124 key = tcp_v6_md5_do_lookup(sk, &newsk->sk_v6_daddr); 1125 if (key) { 1126 /* We're using one, so create a matching key 1127 * on the newsk structure. If we fail to get 1128 * memory, then we end up not copying the key 1129 * across. Shucks. 1130 */ 1131 tcp_md5_do_add(newsk, (union tcp_md5_addr *)&newsk->sk_v6_daddr, 1132 AF_INET6, key->key, key->keylen, 1133 sk_gfp_atomic(sk, GFP_ATOMIC)); 1134 } 1135 #endif 1136 1137 if (__inet_inherit_port(sk, newsk) < 0) { 1138 inet_csk_prepare_forced_close(newsk); 1139 tcp_done(newsk); 1140 goto out; 1141 } 1142 *own_req = inet_ehash_nolisten(newsk, req_to_sk(req_unhash)); 1143 /* Clone pktoptions received with SYN, if we own the req */ 1144 if (*own_req && ireq->pktopts) { 1145 newnp->pktoptions = skb_clone(ireq->pktopts, 1146 sk_gfp_atomic(sk, GFP_ATOMIC)); 1147 consume_skb(ireq->pktopts); 1148 ireq->pktopts = NULL; 1149 if (newnp->pktoptions) 1150 skb_set_owner_r(newnp->pktoptions, newsk); 1151 } 1152 1153 return newsk; 1154 1155 out_overflow: 1156 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS); 1157 out_nonewsk: 1158 dst_release(dst); 1159 out: 1160 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS); 1161 return NULL; 1162 } 1163 1164 /* The socket must have it's spinlock held when we get 1165 * here, unless it is a TCP_LISTEN socket. 1166 * 1167 * We have a potential double-lock case here, so even when 1168 * doing backlog processing we use the BH locking scheme. 1169 * This is because we cannot sleep with the original spinlock 1170 * held. 1171 */ 1172 static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) 1173 { 1174 struct ipv6_pinfo *np = inet6_sk(sk); 1175 struct tcp_sock *tp; 1176 struct sk_buff *opt_skb = NULL; 1177 1178 /* Imagine: socket is IPv6. IPv4 packet arrives, 1179 goes to IPv4 receive handler and backlogged. 1180 From backlog it always goes here. Kerboom... 1181 Fortunately, tcp_rcv_established and rcv_established 1182 handle them correctly, but it is not case with 1183 tcp_v6_hnd_req and tcp_v6_send_reset(). --ANK 1184 */ 1185 1186 if (skb->protocol == htons(ETH_P_IP)) 1187 return tcp_v4_do_rcv(sk, skb); 1188 1189 if (sk_filter(sk, skb)) 1190 goto discard; 1191 1192 /* 1193 * socket locking is here for SMP purposes as backlog rcv 1194 * is currently called with bh processing disabled. 1195 */ 1196 1197 /* Do Stevens' IPV6_PKTOPTIONS. 1198 1199 Yes, guys, it is the only place in our code, where we 1200 may make it not affecting IPv4. 1201 The rest of code is protocol independent, 1202 and I do not like idea to uglify IPv4. 1203 1204 Actually, all the idea behind IPV6_PKTOPTIONS 1205 looks not very well thought. For now we latch 1206 options, received in the last packet, enqueued 1207 by tcp. Feel free to propose better solution. 1208 --ANK (980728) 1209 */ 1210 if (np->rxopt.all) 1211 opt_skb = skb_clone(skb, sk_gfp_atomic(sk, GFP_ATOMIC)); 1212 1213 if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */ 1214 struct dst_entry *dst = sk->sk_rx_dst; 1215 1216 sock_rps_save_rxhash(sk, skb); 1217 sk_mark_napi_id(sk, skb); 1218 if (dst) { 1219 if (inet_sk(sk)->rx_dst_ifindex != skb->skb_iif || 1220 dst->ops->check(dst, np->rx_dst_cookie) == NULL) { 1221 dst_release(dst); 1222 sk->sk_rx_dst = NULL; 1223 } 1224 } 1225 1226 tcp_rcv_established(sk, skb, tcp_hdr(skb), skb->len); 1227 if (opt_skb) 1228 goto ipv6_pktoptions; 1229 return 0; 1230 } 1231 1232 if (tcp_checksum_complete(skb)) 1233 goto csum_err; 1234 1235 if (sk->sk_state == TCP_LISTEN) { 1236 struct sock *nsk = tcp_v6_cookie_check(sk, skb); 1237 1238 if (!nsk) 1239 goto discard; 1240 1241 if (nsk != sk) { 1242 sock_rps_save_rxhash(nsk, skb); 1243 sk_mark_napi_id(nsk, skb); 1244 if (tcp_child_process(sk, nsk, skb)) 1245 goto reset; 1246 if (opt_skb) 1247 __kfree_skb(opt_skb); 1248 return 0; 1249 } 1250 } else 1251 sock_rps_save_rxhash(sk, skb); 1252 1253 if (tcp_rcv_state_process(sk, skb)) 1254 goto reset; 1255 if (opt_skb) 1256 goto ipv6_pktoptions; 1257 return 0; 1258 1259 reset: 1260 tcp_v6_send_reset(sk, skb); 1261 discard: 1262 if (opt_skb) 1263 __kfree_skb(opt_skb); 1264 kfree_skb(skb); 1265 return 0; 1266 csum_err: 1267 TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_CSUMERRORS); 1268 TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_INERRS); 1269 goto discard; 1270 1271 1272 ipv6_pktoptions: 1273 /* Do you ask, what is it? 1274 1275 1. skb was enqueued by tcp. 1276 2. skb is added to tail of read queue, rather than out of order. 1277 3. socket is not in passive state. 1278 4. Finally, it really contains options, which user wants to receive. 1279 */ 1280 tp = tcp_sk(sk); 1281 if (TCP_SKB_CB(opt_skb)->end_seq == tp->rcv_nxt && 1282 !((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))) { 1283 if (np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo) 1284 np->mcast_oif = tcp_v6_iif(opt_skb); 1285 if (np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) 1286 np->mcast_hops = ipv6_hdr(opt_skb)->hop_limit; 1287 if (np->rxopt.bits.rxflow || np->rxopt.bits.rxtclass) 1288 np->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(opt_skb)); 1289 if (np->repflow) 1290 np->flow_label = ip6_flowlabel(ipv6_hdr(opt_skb)); 1291 if (ipv6_opt_accepted(sk, opt_skb, &TCP_SKB_CB(opt_skb)->header.h6)) { 1292 skb_set_owner_r(opt_skb, sk); 1293 opt_skb = xchg(&np->pktoptions, opt_skb); 1294 } else { 1295 __kfree_skb(opt_skb); 1296 opt_skb = xchg(&np->pktoptions, NULL); 1297 } 1298 } 1299 1300 kfree_skb(opt_skb); 1301 return 0; 1302 } 1303 1304 static void tcp_v6_fill_cb(struct sk_buff *skb, const struct ipv6hdr *hdr, 1305 const struct tcphdr *th) 1306 { 1307 /* This is tricky: we move IP6CB at its correct location into 1308 * TCP_SKB_CB(). It must be done after xfrm6_policy_check(), because 1309 * _decode_session6() uses IP6CB(). 1310 * barrier() makes sure compiler won't play aliasing games. 1311 */ 1312 memmove(&TCP_SKB_CB(skb)->header.h6, IP6CB(skb), 1313 sizeof(struct inet6_skb_parm)); 1314 barrier(); 1315 1316 TCP_SKB_CB(skb)->seq = ntohl(th->seq); 1317 TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin + 1318 skb->len - th->doff*4); 1319 TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq); 1320 TCP_SKB_CB(skb)->tcp_flags = tcp_flag_byte(th); 1321 TCP_SKB_CB(skb)->tcp_tw_isn = 0; 1322 TCP_SKB_CB(skb)->ip_dsfield = ipv6_get_dsfield(hdr); 1323 TCP_SKB_CB(skb)->sacked = 0; 1324 } 1325 1326 static void tcp_v6_restore_cb(struct sk_buff *skb) 1327 { 1328 /* We need to move header back to the beginning if xfrm6_policy_check() 1329 * and tcp_v6_fill_cb() are going to be called again. 1330 */ 1331 memmove(IP6CB(skb), &TCP_SKB_CB(skb)->header.h6, 1332 sizeof(struct inet6_skb_parm)); 1333 } 1334 1335 static int tcp_v6_rcv(struct sk_buff *skb) 1336 { 1337 const struct tcphdr *th; 1338 const struct ipv6hdr *hdr; 1339 struct sock *sk; 1340 int ret; 1341 struct net *net = dev_net(skb->dev); 1342 1343 if (skb->pkt_type != PACKET_HOST) 1344 goto discard_it; 1345 1346 /* 1347 * Count it even if it's bad. 1348 */ 1349 TCP_INC_STATS_BH(net, TCP_MIB_INSEGS); 1350 1351 if (!pskb_may_pull(skb, sizeof(struct tcphdr))) 1352 goto discard_it; 1353 1354 th = tcp_hdr(skb); 1355 1356 if (th->doff < sizeof(struct tcphdr)/4) 1357 goto bad_packet; 1358 if (!pskb_may_pull(skb, th->doff*4)) 1359 goto discard_it; 1360 1361 if (skb_checksum_init(skb, IPPROTO_TCP, ip6_compute_pseudo)) 1362 goto csum_error; 1363 1364 th = tcp_hdr(skb); 1365 hdr = ipv6_hdr(skb); 1366 1367 lookup: 1368 sk = __inet6_lookup_skb(&tcp_hashinfo, skb, th->source, th->dest, 1369 inet6_iif(skb)); 1370 if (!sk) 1371 goto no_tcp_socket; 1372 1373 process: 1374 if (sk->sk_state == TCP_TIME_WAIT) 1375 goto do_time_wait; 1376 1377 if (sk->sk_state == TCP_NEW_SYN_RECV) { 1378 struct request_sock *req = inet_reqsk(sk); 1379 struct sock *nsk = NULL; 1380 1381 sk = req->rsk_listener; 1382 tcp_v6_fill_cb(skb, hdr, th); 1383 if (tcp_v6_inbound_md5_hash(sk, skb)) { 1384 reqsk_put(req); 1385 goto discard_it; 1386 } 1387 if (likely(sk->sk_state == TCP_LISTEN)) { 1388 nsk = tcp_check_req(sk, skb, req, false); 1389 } else { 1390 inet_csk_reqsk_queue_drop_and_put(sk, req); 1391 goto lookup; 1392 } 1393 if (!nsk) { 1394 reqsk_put(req); 1395 goto discard_it; 1396 } 1397 if (nsk == sk) { 1398 sock_hold(sk); 1399 reqsk_put(req); 1400 tcp_v6_restore_cb(skb); 1401 } else if (tcp_child_process(sk, nsk, skb)) { 1402 tcp_v6_send_reset(nsk, skb); 1403 goto discard_it; 1404 } else { 1405 return 0; 1406 } 1407 } 1408 if (hdr->hop_limit < inet6_sk(sk)->min_hopcount) { 1409 NET_INC_STATS_BH(net, LINUX_MIB_TCPMINTTLDROP); 1410 goto discard_and_relse; 1411 } 1412 1413 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) 1414 goto discard_and_relse; 1415 1416 tcp_v6_fill_cb(skb, hdr, th); 1417 1418 if (tcp_v6_inbound_md5_hash(sk, skb)) 1419 goto discard_and_relse; 1420 1421 if (sk_filter(sk, skb)) 1422 goto discard_and_relse; 1423 1424 skb->dev = NULL; 1425 1426 if (sk->sk_state == TCP_LISTEN) { 1427 ret = tcp_v6_do_rcv(sk, skb); 1428 goto put_and_return; 1429 } 1430 1431 sk_incoming_cpu_update(sk); 1432 1433 bh_lock_sock_nested(sk); 1434 tcp_sk(sk)->segs_in += max_t(u16, 1, skb_shinfo(skb)->gso_segs); 1435 ret = 0; 1436 if (!sock_owned_by_user(sk)) { 1437 if (!tcp_prequeue(sk, skb)) 1438 ret = tcp_v6_do_rcv(sk, skb); 1439 } else if (unlikely(sk_add_backlog(sk, skb, 1440 sk->sk_rcvbuf + sk->sk_sndbuf))) { 1441 bh_unlock_sock(sk); 1442 NET_INC_STATS_BH(net, LINUX_MIB_TCPBACKLOGDROP); 1443 goto discard_and_relse; 1444 } 1445 bh_unlock_sock(sk); 1446 1447 put_and_return: 1448 sock_put(sk); 1449 return ret ? -1 : 0; 1450 1451 no_tcp_socket: 1452 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 1453 goto discard_it; 1454 1455 tcp_v6_fill_cb(skb, hdr, th); 1456 1457 if (tcp_checksum_complete(skb)) { 1458 csum_error: 1459 TCP_INC_STATS_BH(net, TCP_MIB_CSUMERRORS); 1460 bad_packet: 1461 TCP_INC_STATS_BH(net, TCP_MIB_INERRS); 1462 } else { 1463 tcp_v6_send_reset(NULL, skb); 1464 } 1465 1466 discard_it: 1467 kfree_skb(skb); 1468 return 0; 1469 1470 discard_and_relse: 1471 sock_put(sk); 1472 goto discard_it; 1473 1474 do_time_wait: 1475 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) { 1476 inet_twsk_put(inet_twsk(sk)); 1477 goto discard_it; 1478 } 1479 1480 tcp_v6_fill_cb(skb, hdr, th); 1481 1482 if (tcp_checksum_complete(skb)) { 1483 inet_twsk_put(inet_twsk(sk)); 1484 goto csum_error; 1485 } 1486 1487 switch (tcp_timewait_state_process(inet_twsk(sk), skb, th)) { 1488 case TCP_TW_SYN: 1489 { 1490 struct sock *sk2; 1491 1492 sk2 = inet6_lookup_listener(dev_net(skb->dev), &tcp_hashinfo, 1493 &ipv6_hdr(skb)->saddr, th->source, 1494 &ipv6_hdr(skb)->daddr, 1495 ntohs(th->dest), tcp_v6_iif(skb)); 1496 if (sk2) { 1497 struct inet_timewait_sock *tw = inet_twsk(sk); 1498 inet_twsk_deschedule_put(tw); 1499 sk = sk2; 1500 tcp_v6_restore_cb(skb); 1501 goto process; 1502 } 1503 /* Fall through to ACK */ 1504 } 1505 case TCP_TW_ACK: 1506 tcp_v6_timewait_ack(sk, skb); 1507 break; 1508 case TCP_TW_RST: 1509 tcp_v6_restore_cb(skb); 1510 goto no_tcp_socket; 1511 case TCP_TW_SUCCESS: 1512 ; 1513 } 1514 goto discard_it; 1515 } 1516 1517 static void tcp_v6_early_demux(struct sk_buff *skb) 1518 { 1519 const struct ipv6hdr *hdr; 1520 const struct tcphdr *th; 1521 struct sock *sk; 1522 1523 if (skb->pkt_type != PACKET_HOST) 1524 return; 1525 1526 if (!pskb_may_pull(skb, skb_transport_offset(skb) + sizeof(struct tcphdr))) 1527 return; 1528 1529 hdr = ipv6_hdr(skb); 1530 th = tcp_hdr(skb); 1531 1532 if (th->doff < sizeof(struct tcphdr) / 4) 1533 return; 1534 1535 /* Note : We use inet6_iif() here, not tcp_v6_iif() */ 1536 sk = __inet6_lookup_established(dev_net(skb->dev), &tcp_hashinfo, 1537 &hdr->saddr, th->source, 1538 &hdr->daddr, ntohs(th->dest), 1539 inet6_iif(skb)); 1540 if (sk) { 1541 skb->sk = sk; 1542 skb->destructor = sock_edemux; 1543 if (sk_fullsock(sk)) { 1544 struct dst_entry *dst = READ_ONCE(sk->sk_rx_dst); 1545 1546 if (dst) 1547 dst = dst_check(dst, inet6_sk(sk)->rx_dst_cookie); 1548 if (dst && 1549 inet_sk(sk)->rx_dst_ifindex == skb->skb_iif) 1550 skb_dst_set_noref(skb, dst); 1551 } 1552 } 1553 } 1554 1555 static struct timewait_sock_ops tcp6_timewait_sock_ops = { 1556 .twsk_obj_size = sizeof(struct tcp6_timewait_sock), 1557 .twsk_unique = tcp_twsk_unique, 1558 .twsk_destructor = tcp_twsk_destructor, 1559 }; 1560 1561 static const struct inet_connection_sock_af_ops ipv6_specific = { 1562 .queue_xmit = inet6_csk_xmit, 1563 .send_check = tcp_v6_send_check, 1564 .rebuild_header = inet6_sk_rebuild_header, 1565 .sk_rx_dst_set = inet6_sk_rx_dst_set, 1566 .conn_request = tcp_v6_conn_request, 1567 .syn_recv_sock = tcp_v6_syn_recv_sock, 1568 .net_header_len = sizeof(struct ipv6hdr), 1569 .net_frag_header_len = sizeof(struct frag_hdr), 1570 .setsockopt = ipv6_setsockopt, 1571 .getsockopt = ipv6_getsockopt, 1572 .addr2sockaddr = inet6_csk_addr2sockaddr, 1573 .sockaddr_len = sizeof(struct sockaddr_in6), 1574 .bind_conflict = inet6_csk_bind_conflict, 1575 #ifdef CONFIG_COMPAT 1576 .compat_setsockopt = compat_ipv6_setsockopt, 1577 .compat_getsockopt = compat_ipv6_getsockopt, 1578 #endif 1579 .mtu_reduced = tcp_v6_mtu_reduced, 1580 }; 1581 1582 #ifdef CONFIG_TCP_MD5SIG 1583 static const struct tcp_sock_af_ops tcp_sock_ipv6_specific = { 1584 .md5_lookup = tcp_v6_md5_lookup, 1585 .calc_md5_hash = tcp_v6_md5_hash_skb, 1586 .md5_parse = tcp_v6_parse_md5_keys, 1587 }; 1588 #endif 1589 1590 /* 1591 * TCP over IPv4 via INET6 API 1592 */ 1593 static const struct inet_connection_sock_af_ops ipv6_mapped = { 1594 .queue_xmit = ip_queue_xmit, 1595 .send_check = tcp_v4_send_check, 1596 .rebuild_header = inet_sk_rebuild_header, 1597 .sk_rx_dst_set = inet_sk_rx_dst_set, 1598 .conn_request = tcp_v6_conn_request, 1599 .syn_recv_sock = tcp_v6_syn_recv_sock, 1600 .net_header_len = sizeof(struct iphdr), 1601 .setsockopt = ipv6_setsockopt, 1602 .getsockopt = ipv6_getsockopt, 1603 .addr2sockaddr = inet6_csk_addr2sockaddr, 1604 .sockaddr_len = sizeof(struct sockaddr_in6), 1605 .bind_conflict = inet6_csk_bind_conflict, 1606 #ifdef CONFIG_COMPAT 1607 .compat_setsockopt = compat_ipv6_setsockopt, 1608 .compat_getsockopt = compat_ipv6_getsockopt, 1609 #endif 1610 .mtu_reduced = tcp_v4_mtu_reduced, 1611 }; 1612 1613 #ifdef CONFIG_TCP_MD5SIG 1614 static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific = { 1615 .md5_lookup = tcp_v4_md5_lookup, 1616 .calc_md5_hash = tcp_v4_md5_hash_skb, 1617 .md5_parse = tcp_v6_parse_md5_keys, 1618 }; 1619 #endif 1620 1621 /* NOTE: A lot of things set to zero explicitly by call to 1622 * sk_alloc() so need not be done here. 1623 */ 1624 static int tcp_v6_init_sock(struct sock *sk) 1625 { 1626 struct inet_connection_sock *icsk = inet_csk(sk); 1627 1628 tcp_init_sock(sk); 1629 1630 icsk->icsk_af_ops = &ipv6_specific; 1631 1632 #ifdef CONFIG_TCP_MD5SIG 1633 tcp_sk(sk)->af_specific = &tcp_sock_ipv6_specific; 1634 #endif 1635 1636 return 0; 1637 } 1638 1639 static void tcp_v6_destroy_sock(struct sock *sk) 1640 { 1641 tcp_v4_destroy_sock(sk); 1642 inet6_destroy_sock(sk); 1643 } 1644 1645 #ifdef CONFIG_PROC_FS 1646 /* Proc filesystem TCPv6 sock list dumping. */ 1647 static void get_openreq6(struct seq_file *seq, 1648 const struct request_sock *req, int i) 1649 { 1650 long ttd = req->rsk_timer.expires - jiffies; 1651 const struct in6_addr *src = &inet_rsk(req)->ir_v6_loc_addr; 1652 const struct in6_addr *dest = &inet_rsk(req)->ir_v6_rmt_addr; 1653 1654 if (ttd < 0) 1655 ttd = 0; 1656 1657 seq_printf(seq, 1658 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1659 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %d %d %pK\n", 1660 i, 1661 src->s6_addr32[0], src->s6_addr32[1], 1662 src->s6_addr32[2], src->s6_addr32[3], 1663 inet_rsk(req)->ir_num, 1664 dest->s6_addr32[0], dest->s6_addr32[1], 1665 dest->s6_addr32[2], dest->s6_addr32[3], 1666 ntohs(inet_rsk(req)->ir_rmt_port), 1667 TCP_SYN_RECV, 1668 0, 0, /* could print option size, but that is af dependent. */ 1669 1, /* timers active (only the expire timer) */ 1670 jiffies_to_clock_t(ttd), 1671 req->num_timeout, 1672 from_kuid_munged(seq_user_ns(seq), 1673 sock_i_uid(req->rsk_listener)), 1674 0, /* non standard timer */ 1675 0, /* open_requests have no inode */ 1676 0, req); 1677 } 1678 1679 static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i) 1680 { 1681 const struct in6_addr *dest, *src; 1682 __u16 destp, srcp; 1683 int timer_active; 1684 unsigned long timer_expires; 1685 const struct inet_sock *inet = inet_sk(sp); 1686 const struct tcp_sock *tp = tcp_sk(sp); 1687 const struct inet_connection_sock *icsk = inet_csk(sp); 1688 const struct fastopen_queue *fastopenq = &icsk->icsk_accept_queue.fastopenq; 1689 1690 dest = &sp->sk_v6_daddr; 1691 src = &sp->sk_v6_rcv_saddr; 1692 destp = ntohs(inet->inet_dport); 1693 srcp = ntohs(inet->inet_sport); 1694 1695 if (icsk->icsk_pending == ICSK_TIME_RETRANS) { 1696 timer_active = 1; 1697 timer_expires = icsk->icsk_timeout; 1698 } else if (icsk->icsk_pending == ICSK_TIME_PROBE0) { 1699 timer_active = 4; 1700 timer_expires = icsk->icsk_timeout; 1701 } else if (timer_pending(&sp->sk_timer)) { 1702 timer_active = 2; 1703 timer_expires = sp->sk_timer.expires; 1704 } else { 1705 timer_active = 0; 1706 timer_expires = jiffies; 1707 } 1708 1709 seq_printf(seq, 1710 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1711 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %lu %lu %u %u %d\n", 1712 i, 1713 src->s6_addr32[0], src->s6_addr32[1], 1714 src->s6_addr32[2], src->s6_addr32[3], srcp, 1715 dest->s6_addr32[0], dest->s6_addr32[1], 1716 dest->s6_addr32[2], dest->s6_addr32[3], destp, 1717 sp->sk_state, 1718 tp->write_seq-tp->snd_una, 1719 (sp->sk_state == TCP_LISTEN) ? sp->sk_ack_backlog : (tp->rcv_nxt - tp->copied_seq), 1720 timer_active, 1721 jiffies_delta_to_clock_t(timer_expires - jiffies), 1722 icsk->icsk_retransmits, 1723 from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)), 1724 icsk->icsk_probes_out, 1725 sock_i_ino(sp), 1726 atomic_read(&sp->sk_refcnt), sp, 1727 jiffies_to_clock_t(icsk->icsk_rto), 1728 jiffies_to_clock_t(icsk->icsk_ack.ato), 1729 (icsk->icsk_ack.quick << 1) | icsk->icsk_ack.pingpong, 1730 tp->snd_cwnd, 1731 sp->sk_state == TCP_LISTEN ? 1732 fastopenq->max_qlen : 1733 (tcp_in_initial_slowstart(tp) ? -1 : tp->snd_ssthresh) 1734 ); 1735 } 1736 1737 static void get_timewait6_sock(struct seq_file *seq, 1738 struct inet_timewait_sock *tw, int i) 1739 { 1740 long delta = tw->tw_timer.expires - jiffies; 1741 const struct in6_addr *dest, *src; 1742 __u16 destp, srcp; 1743 1744 dest = &tw->tw_v6_daddr; 1745 src = &tw->tw_v6_rcv_saddr; 1746 destp = ntohs(tw->tw_dport); 1747 srcp = ntohs(tw->tw_sport); 1748 1749 seq_printf(seq, 1750 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1751 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK\n", 1752 i, 1753 src->s6_addr32[0], src->s6_addr32[1], 1754 src->s6_addr32[2], src->s6_addr32[3], srcp, 1755 dest->s6_addr32[0], dest->s6_addr32[1], 1756 dest->s6_addr32[2], dest->s6_addr32[3], destp, 1757 tw->tw_substate, 0, 0, 1758 3, jiffies_delta_to_clock_t(delta), 0, 0, 0, 0, 1759 atomic_read(&tw->tw_refcnt), tw); 1760 } 1761 1762 static int tcp6_seq_show(struct seq_file *seq, void *v) 1763 { 1764 struct tcp_iter_state *st; 1765 struct sock *sk = v; 1766 1767 if (v == SEQ_START_TOKEN) { 1768 seq_puts(seq, 1769 " sl " 1770 "local_address " 1771 "remote_address " 1772 "st tx_queue rx_queue tr tm->when retrnsmt" 1773 " uid timeout inode\n"); 1774 goto out; 1775 } 1776 st = seq->private; 1777 1778 if (sk->sk_state == TCP_TIME_WAIT) 1779 get_timewait6_sock(seq, v, st->num); 1780 else if (sk->sk_state == TCP_NEW_SYN_RECV) 1781 get_openreq6(seq, v, st->num); 1782 else 1783 get_tcp6_sock(seq, v, st->num); 1784 out: 1785 return 0; 1786 } 1787 1788 static const struct file_operations tcp6_afinfo_seq_fops = { 1789 .owner = THIS_MODULE, 1790 .open = tcp_seq_open, 1791 .read = seq_read, 1792 .llseek = seq_lseek, 1793 .release = seq_release_net 1794 }; 1795 1796 static struct tcp_seq_afinfo tcp6_seq_afinfo = { 1797 .name = "tcp6", 1798 .family = AF_INET6, 1799 .seq_fops = &tcp6_afinfo_seq_fops, 1800 .seq_ops = { 1801 .show = tcp6_seq_show, 1802 }, 1803 }; 1804 1805 int __net_init tcp6_proc_init(struct net *net) 1806 { 1807 return tcp_proc_register(net, &tcp6_seq_afinfo); 1808 } 1809 1810 void tcp6_proc_exit(struct net *net) 1811 { 1812 tcp_proc_unregister(net, &tcp6_seq_afinfo); 1813 } 1814 #endif 1815 1816 static void tcp_v6_clear_sk(struct sock *sk, int size) 1817 { 1818 struct inet_sock *inet = inet_sk(sk); 1819 1820 /* we do not want to clear pinet6 field, because of RCU lookups */ 1821 sk_prot_clear_nulls(sk, offsetof(struct inet_sock, pinet6)); 1822 1823 size -= offsetof(struct inet_sock, pinet6) + sizeof(inet->pinet6); 1824 memset(&inet->pinet6 + 1, 0, size); 1825 } 1826 1827 struct proto tcpv6_prot = { 1828 .name = "TCPv6", 1829 .owner = THIS_MODULE, 1830 .close = tcp_close, 1831 .connect = tcp_v6_connect, 1832 .disconnect = tcp_disconnect, 1833 .accept = inet_csk_accept, 1834 .ioctl = tcp_ioctl, 1835 .init = tcp_v6_init_sock, 1836 .destroy = tcp_v6_destroy_sock, 1837 .shutdown = tcp_shutdown, 1838 .setsockopt = tcp_setsockopt, 1839 .getsockopt = tcp_getsockopt, 1840 .recvmsg = tcp_recvmsg, 1841 .sendmsg = tcp_sendmsg, 1842 .sendpage = tcp_sendpage, 1843 .backlog_rcv = tcp_v6_do_rcv, 1844 .release_cb = tcp_release_cb, 1845 .hash = inet_hash, 1846 .unhash = inet_unhash, 1847 .get_port = inet_csk_get_port, 1848 .enter_memory_pressure = tcp_enter_memory_pressure, 1849 .stream_memory_free = tcp_stream_memory_free, 1850 .sockets_allocated = &tcp_sockets_allocated, 1851 .memory_allocated = &tcp_memory_allocated, 1852 .memory_pressure = &tcp_memory_pressure, 1853 .orphan_count = &tcp_orphan_count, 1854 .sysctl_mem = sysctl_tcp_mem, 1855 .sysctl_wmem = sysctl_tcp_wmem, 1856 .sysctl_rmem = sysctl_tcp_rmem, 1857 .max_header = MAX_TCP_HEADER, 1858 .obj_size = sizeof(struct tcp6_sock), 1859 .slab_flags = SLAB_DESTROY_BY_RCU, 1860 .twsk_prot = &tcp6_timewait_sock_ops, 1861 .rsk_prot = &tcp6_request_sock_ops, 1862 .h.hashinfo = &tcp_hashinfo, 1863 .no_autobind = true, 1864 #ifdef CONFIG_COMPAT 1865 .compat_setsockopt = compat_tcp_setsockopt, 1866 .compat_getsockopt = compat_tcp_getsockopt, 1867 #endif 1868 #ifdef CONFIG_MEMCG_KMEM 1869 .proto_cgroup = tcp_proto_cgroup, 1870 #endif 1871 .clear_sk = tcp_v6_clear_sk, 1872 }; 1873 1874 static const struct inet6_protocol tcpv6_protocol = { 1875 .early_demux = tcp_v6_early_demux, 1876 .handler = tcp_v6_rcv, 1877 .err_handler = tcp_v6_err, 1878 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 1879 }; 1880 1881 static struct inet_protosw tcpv6_protosw = { 1882 .type = SOCK_STREAM, 1883 .protocol = IPPROTO_TCP, 1884 .prot = &tcpv6_prot, 1885 .ops = &inet6_stream_ops, 1886 .flags = INET_PROTOSW_PERMANENT | 1887 INET_PROTOSW_ICSK, 1888 }; 1889 1890 static int __net_init tcpv6_net_init(struct net *net) 1891 { 1892 return inet_ctl_sock_create(&net->ipv6.tcp_sk, PF_INET6, 1893 SOCK_RAW, IPPROTO_TCP, net); 1894 } 1895 1896 static void __net_exit tcpv6_net_exit(struct net *net) 1897 { 1898 inet_ctl_sock_destroy(net->ipv6.tcp_sk); 1899 } 1900 1901 static void __net_exit tcpv6_net_exit_batch(struct list_head *net_exit_list) 1902 { 1903 inet_twsk_purge(&tcp_hashinfo, &tcp_death_row, AF_INET6); 1904 } 1905 1906 static struct pernet_operations tcpv6_net_ops = { 1907 .init = tcpv6_net_init, 1908 .exit = tcpv6_net_exit, 1909 .exit_batch = tcpv6_net_exit_batch, 1910 }; 1911 1912 int __init tcpv6_init(void) 1913 { 1914 int ret; 1915 1916 ret = inet6_add_protocol(&tcpv6_protocol, IPPROTO_TCP); 1917 if (ret) 1918 goto out; 1919 1920 /* register inet6 protocol */ 1921 ret = inet6_register_protosw(&tcpv6_protosw); 1922 if (ret) 1923 goto out_tcpv6_protocol; 1924 1925 ret = register_pernet_subsys(&tcpv6_net_ops); 1926 if (ret) 1927 goto out_tcpv6_protosw; 1928 out: 1929 return ret; 1930 1931 out_tcpv6_protosw: 1932 inet6_unregister_protosw(&tcpv6_protosw); 1933 out_tcpv6_protocol: 1934 inet6_del_protocol(&tcpv6_protocol, IPPROTO_TCP); 1935 goto out; 1936 } 1937 1938 void tcpv6_exit(void) 1939 { 1940 unregister_pernet_subsys(&tcpv6_net_ops); 1941 inet6_unregister_protosw(&tcpv6_protosw); 1942 inet6_del_protocol(&tcpv6_protocol, IPPROTO_TCP); 1943 } 1944