vcs.maemo.org Git - h-e-n/blob - net/ipv6/tcp_ipv6.c

   1 /*
   2  *      TCP over IPv6
   3  *      Linux INET6 implementation
   4  *
   5  *      Authors:
   6  *      Pedro Roque             <roque@di.fc.ul.pt>
   7  *
   8  *      $Id: tcp_ipv6.c,v 1.144 2002/02/01 22:01:04 davem Exp $
   9  *
  10  *      Based on:
  11  *      linux/net/ipv4/tcp.c
  12  *      linux/net/ipv4/tcp_input.c
  13  *      linux/net/ipv4/tcp_output.c
  14  *
  15  *      Fixes:
  16  *      Hideaki YOSHIFUJI       :       sin6_scope_id support
  17  *      YOSHIFUJI Hideaki @USAGI and:   Support IPV6_V6ONLY socket option, which
  18  *      Alexey Kuznetsov                allow both IPv4 and IPv6 sockets to bind
  19  *                                      a single port at the same time.
  20  *      YOSHIFUJI Hideaki @USAGI:       convert /proc/net/tcp6 to seq_file.
  21  *
  22  *      This program is free software; you can redistribute it and/or
  23  *      modify it under the terms of the GNU General Public License
  24  *      as published by the Free Software Foundation; either version
  25  *      2 of the License, or (at your option) any later version.
  26  */
  27
  28 #include <linux/module.h>
  29 #include <linux/config.h>
  30 #include <linux/errno.h>
  31 #include <linux/types.h>
  32 #include <linux/socket.h>
  33 #include <linux/sockios.h>
  34 #include <linux/net.h>
  35 #include <linux/jiffies.h>
  36 #include <linux/in.h>
  37 #include <linux/in6.h>
  38 #include <linux/netdevice.h>
  39 #include <linux/init.h>
  40 #include <linux/jhash.h>
  41 #include <linux/ipsec.h>
  42 #include <linux/times.h>
  43
  44 #include <linux/ipv6.h>
  45 #include <linux/icmpv6.h>
  46 #include <linux/random.h>
  47
  48 #include <net/tcp.h>
  49 #include <net/ndisc.h>
  50 #include <net/inet6_hashtables.h>
  51 #include <net/inet6_connection_sock.h>
  52 #include <net/ipv6.h>
  53 #include <net/transp_v6.h>
  54 #include <net/addrconf.h>
  55 #include <net/ip6_route.h>
  56 #include <net/ip6_checksum.h>
  57 #include <net/inet_ecn.h>
  58 #include <net/protocol.h>
  59 #include <net/xfrm.h>
  60 #include <net/addrconf.h>
  61 #include <net/snmp.h>
  62 #include <net/dsfield.h>
  63
  64 #include <asm/uaccess.h>
  65
  66 #include <linux/proc_fs.h>
  67 #include <linux/seq_file.h>
  68
  69 static void     tcp_v6_send_reset(struct sk_buff *skb);
  70 static void     tcp_v6_reqsk_send_ack(struct sk_buff *skb, struct request_sock *req);
  71 static void     tcp_v6_send_check(struct sock *sk, struct tcphdr *th, int len,
  72                                   struct sk_buff *skb);
  73
  74 static int      tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb);
  75 static int      tcp_v6_xmit(struct sk_buff *skb, int ipfragok);
  76
  77 static struct tcp_func ipv6_mapped;
  78 static struct tcp_func ipv6_specific;
  79
  80 int inet6_csk_bind_conflict(const struct sock *sk,
  81                             const struct inet_bind_bucket *tb)
  82 {
  83         const struct sock *sk2;
  84         const struct hlist_node *node;
  85
  86         /* We must walk the whole port owner list in this case. -DaveM */
  87         sk_for_each_bound(sk2, node, &tb->owners) {
  88                 if (sk != sk2 &&
  89                     (!sk->sk_bound_dev_if ||
  90                      !sk2->sk_bound_dev_if ||
  91                      sk->sk_bound_dev_if == sk2->sk_bound_dev_if) &&
  92                     (!sk->sk_reuse || !sk2->sk_reuse ||
  93                      sk2->sk_state == TCP_LISTEN) &&
  94                      ipv6_rcv_saddr_equal(sk, sk2))
  95                         break;
  96         }
  97
  98         return node != NULL;
  99 }
 100
 101 static int tcp_v6_get_port(struct sock *sk, unsigned short snum)
 102 {
 103         return inet_csk_get_port(&tcp_hashinfo, sk, snum,
 104                                  inet6_csk_bind_conflict);
 105 }
 106
 107 static void tcp_v6_hash(struct sock *sk)
 108 {
 109         if (sk->sk_state != TCP_CLOSE) {
 110                 struct tcp_sock *tp = tcp_sk(sk);
 111
 112                 if (tp->af_specific == &ipv6_mapped) {
 113                         tcp_prot.hash(sk);
 114                         return;
 115                 }
 116                 local_bh_disable();
 117                 __inet6_hash(&tcp_hashinfo, sk);
 118                 local_bh_enable();
 119         }
 120 }
 121
 122 static __inline__ u16 tcp_v6_check(struct tcphdr *th, int len,
 123                                    struct in6_addr *saddr,
 124                                    struct in6_addr *daddr,
 125                                    unsigned long base)
 126 {
 127         return csum_ipv6_magic(saddr, daddr, len, IPPROTO_TCP, base);
 128 }
 129
 130 static __u32 tcp_v6_init_sequence(struct sock *sk, struct sk_buff *skb)
 131 {
 132         if (skb->protocol == htons(ETH_P_IPV6)) {
 133                 return secure_tcpv6_sequence_number(skb->nh.ipv6h->daddr.s6_addr32,
 134                                                     skb->nh.ipv6h->saddr.s6_addr32,
 135                                                     skb->h.th->dest,
 136                                                     skb->h.th->source);
 137         } else {
 138                 return secure_tcp_sequence_number(skb->nh.iph->daddr,
 139                                                   skb->nh.iph->saddr,
 140                                                   skb->h.th->dest,
 141                                                   skb->h.th->source);
 142         }
 143 }
 144
 145 static int __tcp_v6_check_established(struct sock *sk, const __u16 lport,
 146                                       struct inet_timewait_sock **twp)
 147 {
 148         struct inet_sock *inet = inet_sk(sk);
 149         const struct ipv6_pinfo *np = inet6_sk(sk);
 150         const struct in6_addr *daddr = &np->rcv_saddr;
 151         const struct in6_addr *saddr = &np->daddr;
 152         const int dif = sk->sk_bound_dev_if;
 153         const u32 ports = INET_COMBINED_PORTS(inet->dport, lport);
 154         unsigned int hash = inet6_ehashfn(daddr, inet->num, saddr, inet->dport);
 155         struct inet_ehash_bucket *head = inet_ehash_bucket(&tcp_hashinfo, hash);
 156         struct sock *sk2;
 157         const struct hlist_node *node;
 158         struct inet_timewait_sock *tw;
 159
 160         prefetch(head->chain.first);
 161         write_lock(&head->lock);
 162
 163         /* Check TIME-WAIT sockets first. */
 164         sk_for_each(sk2, node, &(head + tcp_hashinfo.ehash_size)->chain) {
 165                 const struct tcp6_timewait_sock *tcp6tw = tcp6_twsk(sk2);
 166
 167                 tw = inet_twsk(sk2);
 168
 169                 if(*((__u32 *)&(tw->tw_dport))  == ports        &&
 170                    sk2->sk_family               == PF_INET6     &&
 171                    ipv6_addr_equal(&tcp6tw->tw_v6_daddr, saddr) &&
 172                    ipv6_addr_equal(&tcp6tw->tw_v6_rcv_saddr, daddr)     &&
 173                    sk2->sk_bound_dev_if == sk->sk_bound_dev_if) {
 174                         const struct tcp_timewait_sock *tcptw = tcp_twsk(sk2);
 175                         struct tcp_sock *tp = tcp_sk(sk);
 176
 177                         if (tcptw->tw_ts_recent_stamp &&
 178                             (!twp ||
 179                              (sysctl_tcp_tw_reuse &&
 180                               xtime.tv_sec - tcptw->tw_ts_recent_stamp > 1))) {
 181                                 /* See comment in tcp_ipv4.c */
 182                                 tp->write_seq = tcptw->tw_snd_nxt + 65535 + 2;
 183                                 if (!tp->write_seq)
 184                                         tp->write_seq = 1;
 185                                 tp->rx_opt.ts_recent       = tcptw->tw_ts_recent;
 186                                 tp->rx_opt.ts_recent_stamp = tcptw->tw_ts_recent_stamp;
 187                                 sock_hold(sk2);
 188                                 goto unique;
 189                         } else
 190                                 goto not_unique;
 191                 }
 192         }
 193         tw = NULL;
 194
 195         /* And established part... */
 196         sk_for_each(sk2, node, &head->chain) {
 197                 if (INET6_MATCH(sk2, hash, saddr, daddr, ports, dif))
 198                         goto not_unique;
 199         }
 200
 201 unique:
 202         BUG_TRAP(sk_unhashed(sk));
 203         __sk_add_node(sk, &head->chain);
 204         sk->sk_hash = hash;
 205         sock_prot_inc_use(sk->sk_prot);
 206         write_unlock(&head->lock);
 207
 208         if (twp) {
 209                 *twp = tw;
 210                 NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED);
 211         } else if (tw) {
 212                 /* Silly. Should hash-dance instead... */
 213                 inet_twsk_deschedule(tw, &tcp_death_row);
 214                 NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED);
 215
 216                 inet_twsk_put(tw);
 217         }
 218         return 0;
 219
 220 not_unique:
 221         write_unlock(&head->lock);
 222         return -EADDRNOTAVAIL;
 223 }
 224
 225 static inline u32 tcpv6_port_offset(const struct sock *sk)
 226 {
 227         const struct inet_sock *inet = inet_sk(sk);
 228         const struct ipv6_pinfo *np = inet6_sk(sk);
 229
 230         return secure_tcpv6_port_ephemeral(np->rcv_saddr.s6_addr32,
 231                                            np->daddr.s6_addr32,
 232                                            inet->dport);
 233 }
 234
 235 static int tcp_v6_hash_connect(struct sock *sk)
 236 {
 237         unsigned short snum = inet_sk(sk)->num;
 238         struct inet_bind_hashbucket *head;
 239         struct inet_bind_bucket *tb;
 240         int ret;
 241
 242         if (!snum) {
 243                 int low = sysctl_local_port_range[0];
 244                 int high = sysctl_local_port_range[1];
 245                 int range = high - low;
 246                 int i;
 247                 int port;
 248                 static u32 hint;
 249                 u32 offset = hint + tcpv6_port_offset(sk);
 250                 struct hlist_node *node;
 251                 struct inet_timewait_sock *tw = NULL;
 252
 253                 local_bh_disable();
 254                 for (i = 1; i <= range; i++) {
 255                         port = low + (i + offset) % range;
 256                         head = &tcp_hashinfo.bhash[inet_bhashfn(port, tcp_hashinfo.bhash_size)];
 257                         spin_lock(&head->lock);
 258
 259                         /* Does not bother with rcv_saddr checks,
 260                          * because the established check is already
 261                          * unique enough.
 262                          */
 263                         inet_bind_bucket_for_each(tb, node, &head->chain) {
 264                                 if (tb->port == port) {
 265                                         BUG_TRAP(!hlist_empty(&tb->owners));
 266                                         if (tb->fastreuse >= 0)
 267                                                 goto next_port;
 268                                         if (!__tcp_v6_check_established(sk,
 269                                                                         port,
 270                                                                         &tw))
 271                                                 goto ok;
 272                                         goto next_port;
 273                                 }
 274                         }
 275
 276                         tb = inet_bind_bucket_create(tcp_hashinfo.bind_bucket_cachep, head, port);
 277                         if (!tb) {
 278                                 spin_unlock(&head->lock);
 279                                 break;
 280                         }
 281                         tb->fastreuse = -1;
 282                         goto ok;
 283
 284                 next_port:
 285                         spin_unlock(&head->lock);
 286                 }
 287                 local_bh_enable();
 288
 289                 return -EADDRNOTAVAIL;
 290
 291 ok:
 292                 hint += i;
 293
 294                 /* Head lock still held and bh's disabled */
 295                 inet_bind_hash(sk, tb, port);
 296                 if (sk_unhashed(sk)) {
 297                         inet_sk(sk)->sport = htons(port);
 298                         __inet6_hash(&tcp_hashinfo, sk);
 299                 }
 300                 spin_unlock(&head->lock);
 301
 302                 if (tw) {
 303                         inet_twsk_deschedule(tw, &tcp_death_row);
 304                         inet_twsk_put(tw);
 305                 }
 306
 307                 ret = 0;
 308                 goto out;
 309         }
 310
 311         head = &tcp_hashinfo.bhash[inet_bhashfn(snum, tcp_hashinfo.bhash_size)];
 312         tb   = inet_csk(sk)->icsk_bind_hash;
 313         spin_lock_bh(&head->lock);
 314
 315         if (sk_head(&tb->owners) == sk && !sk->sk_bind_node.next) {
 316                 __inet6_hash(&tcp_hashinfo, sk);
 317                 spin_unlock_bh(&head->lock);
 318                 return 0;
 319         } else {
 320                 spin_unlock(&head->lock);
 321                 /* No definite answer... Walk to established hash table */
 322                 ret = __tcp_v6_check_established(sk, snum, NULL);
 323 out:
 324                 local_bh_enable();
 325                 return ret;
 326         }
 327 }
 328
 329 static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
 330                           int addr_len)
 331 {
 332         struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr;
 333         struct inet_sock *inet = inet_sk(sk);
 334         struct ipv6_pinfo *np = inet6_sk(sk);
 335         struct tcp_sock *tp = tcp_sk(sk);
 336         struct in6_addr *saddr = NULL, *final_p = NULL, final;
 337         struct flowi fl;
 338         struct dst_entry *dst;
 339         int addr_type;
 340         int err;
 341
 342         if (addr_len < SIN6_LEN_RFC2133)
 343                 return -EINVAL;
 344
 345         if (usin->sin6_family != AF_INET6)
 346                 return(-EAFNOSUPPORT);
 347
 348         memset(&fl, 0, sizeof(fl));
 349
 350         if (np->sndflow) {
 351                 fl.fl6_flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK;
 352                 IP6_ECN_flow_init(fl.fl6_flowlabel);
 353                 if (fl.fl6_flowlabel&IPV6_FLOWLABEL_MASK) {
 354                         struct ip6_flowlabel *flowlabel;
 355                         flowlabel = fl6_sock_lookup(sk, fl.fl6_flowlabel);
 356                         if (flowlabel == NULL)
 357                                 return -EINVAL;
 358                         ipv6_addr_copy(&usin->sin6_addr, &flowlabel->dst);
 359                         fl6_sock_release(flowlabel);
 360                 }
 361         }
 362
 363         /*
 364          *      connect() to INADDR_ANY means loopback (BSD'ism).
 365          */
 366
 367         if(ipv6_addr_any(&usin->sin6_addr))
 368                 usin->sin6_addr.s6_addr[15] = 0x1;
 369
 370         addr_type = ipv6_addr_type(&usin->sin6_addr);
 371
 372         if(addr_type & IPV6_ADDR_MULTICAST)
 373                 return -ENETUNREACH;
 374
 375         if (addr_type&IPV6_ADDR_LINKLOCAL) {
 376                 if (addr_len >= sizeof(struct sockaddr_in6) &&
 377                     usin->sin6_scope_id) {
 378                         /* If interface is set while binding, indices
 379                          * must coincide.
 380                          */
 381                         if (sk->sk_bound_dev_if &&
 382                             sk->sk_bound_dev_if != usin->sin6_scope_id)
 383                                 return -EINVAL;
 384
 385                         sk->sk_bound_dev_if = usin->sin6_scope_id;
 386                 }
 387
 388                 /* Connect to link-local address requires an interface */
 389                 if (!sk->sk_bound_dev_if)
 390                         return -EINVAL;
 391         }
 392
 393         if (tp->rx_opt.ts_recent_stamp &&
 394             !ipv6_addr_equal(&np->daddr, &usin->sin6_addr)) {
 395                 tp->rx_opt.ts_recent = 0;
 396                 tp->rx_opt.ts_recent_stamp = 0;
 397                 tp->write_seq = 0;
 398         }
 399
 400         ipv6_addr_copy(&np->daddr, &usin->sin6_addr);
 401         np->flow_label = fl.fl6_flowlabel;
 402
 403         /*
 404          *      TCP over IPv4
 405          */
 406
 407         if (addr_type == IPV6_ADDR_MAPPED) {
 408                 u32 exthdrlen = tp->ext_header_len;
 409                 struct sockaddr_in sin;
 410
 411                 SOCK_DEBUG(sk, "connect: ipv4 mapped\n");
 412
 413                 if (__ipv6_only_sock(sk))
 414                         return -ENETUNREACH;
 415
 416                 sin.sin_family = AF_INET;
 417                 sin.sin_port = usin->sin6_port;
 418                 sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3];
 419
 420                 tp->af_specific = &ipv6_mapped;
 421                 sk->sk_backlog_rcv = tcp_v4_do_rcv;
 422
 423                 err = tcp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin));
 424
 425                 if (err) {
 426                         tp->ext_header_len = exthdrlen;
 427                         tp->af_specific = &ipv6_specific;
 428                         sk->sk_backlog_rcv = tcp_v6_do_rcv;
 429                         goto failure;
 430                 } else {
 431                         ipv6_addr_set(&np->saddr, 0, 0, htonl(0x0000FFFF),
 432                                       inet->saddr);
 433                         ipv6_addr_set(&np->rcv_saddr, 0, 0, htonl(0x0000FFFF),
 434                                       inet->rcv_saddr);
 435                 }
 436
 437                 return err;
 438         }
 439
 440         if (!ipv6_addr_any(&np->rcv_saddr))
 441                 saddr = &np->rcv_saddr;
 442
 443         fl.proto = IPPROTO_TCP;
 444         ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
 445         ipv6_addr_copy(&fl.fl6_src,
 446                        (saddr ? saddr : &np->saddr));
 447         fl.oif = sk->sk_bound_dev_if;
 448         fl.fl_ip_dport = usin->sin6_port;
 449         fl.fl_ip_sport = inet->sport;
 450
 451         if (np->opt && np->opt->srcrt) {
 452                 struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt;
 453                 ipv6_addr_copy(&final, &fl.fl6_dst);
 454                 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
 455                 final_p = &final;
 456         }
 457
 458         err = ip6_dst_lookup(sk, &dst, &fl);
 459         if (err)
 460                 goto failure;
 461         if (final_p)
 462                 ipv6_addr_copy(&fl.fl6_dst, final_p);
 463
 464         if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0)
 465                 goto failure;
 466
 467         if (saddr == NULL) {
 468                 saddr = &fl.fl6_src;
 469                 ipv6_addr_copy(&np->rcv_saddr, saddr);
 470         }
 471
 472         /* set the source address */
 473         ipv6_addr_copy(&np->saddr, saddr);
 474         inet->rcv_saddr = LOOPBACK4_IPV6;
 475
 476         ip6_dst_store(sk, dst, NULL);
 477         sk->sk_route_caps = dst->dev->features &
 478                 ~(NETIF_F_IP_CSUM | NETIF_F_TSO);
 479
 480         tp->ext_header_len = 0;
 481         if (np->opt)
 482                 tp->ext_header_len = np->opt->opt_flen + np->opt->opt_nflen;
 483
 484         tp->rx_opt.mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - sizeof(struct ipv6hdr);
 485
 486         inet->dport = usin->sin6_port;
 487
 488         tcp_set_state(sk, TCP_SYN_SENT);
 489         err = tcp_v6_hash_connect(sk);
 490         if (err)
 491                 goto late_failure;
 492
 493         if (!tp->write_seq)
 494                 tp->write_seq = secure_tcpv6_sequence_number(np->saddr.s6_addr32,
 495                                                              np->daddr.s6_addr32,
 496                                                              inet->sport,
 497                                                              inet->dport);
 498
 499         err = tcp_connect(sk);
 500         if (err)
 501                 goto late_failure;
 502
 503         return 0;
 504
 505 late_failure:
 506         tcp_set_state(sk, TCP_CLOSE);
 507         __sk_dst_reset(sk);
 508 failure:
 509         inet->dport = 0;
 510         sk->sk_route_caps = 0;
 511         return err;
 512 }
 513
 514 static void tcp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 515                 int type, int code, int offset, __u32 info)
 516 {
 517         struct ipv6hdr *hdr = (struct ipv6hdr*)skb->data;
 518         const struct tcphdr *th = (struct tcphdr *)(skb->data+offset);
 519         struct ipv6_pinfo *np;
 520         struct sock *sk;
 521         int err;
 522         struct tcp_sock *tp;
 523         __u32 seq;
 524
 525         sk = inet6_lookup(&tcp_hashinfo, &hdr->daddr, th->dest, &hdr->saddr,
 526                           th->source, skb->dev->ifindex);
 527
 528         if (sk == NULL) {
 529                 ICMP6_INC_STATS_BH(__in6_dev_get(skb->dev), ICMP6_MIB_INERRORS);
 530                 return;
 531         }
 532
 533         if (sk->sk_state == TCP_TIME_WAIT) {
 534                 inet_twsk_put((struct inet_timewait_sock *)sk);
 535                 return;
 536         }
 537
 538         bh_lock_sock(sk);
 539         if (sock_owned_by_user(sk))
 540                 NET_INC_STATS_BH(LINUX_MIB_LOCKDROPPEDICMPS);
 541
 542         if (sk->sk_state == TCP_CLOSE)
 543                 goto out;
 544
 545         tp = tcp_sk(sk);
 546         seq = ntohl(th->seq);
 547         if (sk->sk_state != TCP_LISTEN &&
 548             !between(seq, tp->snd_una, tp->snd_nxt)) {
 549                 NET_INC_STATS_BH(LINUX_MIB_OUTOFWINDOWICMPS);
 550                 goto out;
 551         }
 552
 553         np = inet6_sk(sk);
 554
 555         if (type == ICMPV6_PKT_TOOBIG) {
 556                 struct dst_entry *dst = NULL;
 557
 558                 if (sock_owned_by_user(sk))
 559                         goto out;
 560                 if ((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE))
 561                         goto out;
 562
 563                 /* icmp should have updated the destination cache entry */
 564                 dst = __sk_dst_check(sk, np->dst_cookie);
 565
 566                 if (dst == NULL) {
 567                         struct inet_sock *inet = inet_sk(sk);
 568                         struct flowi fl;
 569
 570                         /* BUGGG_FUTURE: Again, it is not clear how
 571                            to handle rthdr case. Ignore this complexity
 572                            for now.
 573                          */
 574                         memset(&fl, 0, sizeof(fl));
 575                         fl.proto = IPPROTO_TCP;
 576                         ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
 577                         ipv6_addr_copy(&fl.fl6_src, &np->saddr);
 578                         fl.oif = sk->sk_bound_dev_if;
 579                         fl.fl_ip_dport = inet->dport;
 580                         fl.fl_ip_sport = inet->sport;
 581
 582                         if ((err = ip6_dst_lookup(sk, &dst, &fl))) {
 583                                 sk->sk_err_soft = -err;
 584                                 goto out;
 585                         }
 586
 587                         if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) {
 588                                 sk->sk_err_soft = -err;
 589                                 goto out;
 590                         }
 591
 592                 } else
 593                         dst_hold(dst);
 594
 595                 if (tp->pmtu_cookie > dst_mtu(dst)) {
 596                         tcp_sync_mss(sk, dst_mtu(dst));
 597                         tcp_simple_retransmit(sk);
 598                 } /* else let the usual retransmit timer handle it */
 599                 dst_release(dst);
 600                 goto out;
 601         }
 602
 603         icmpv6_err_convert(type, code, &err);
 604
 605         /* Might be for an request_sock */
 606         switch (sk->sk_state) {
 607                 struct request_sock *req, **prev;
 608         case TCP_LISTEN:
 609                 if (sock_owned_by_user(sk))
 610                         goto out;
 611
 612                 req = inet6_csk_search_req(sk, &prev, th->dest, &hdr->daddr,
 613                                            &hdr->saddr, inet6_iif(skb));
 614                 if (!req)
 615                         goto out;
 616
 617                 /* ICMPs are not backlogged, hence we cannot get
 618                  * an established socket here.
 619                  */
 620                 BUG_TRAP(req->sk == NULL);
 621
 622                 if (seq != tcp_rsk(req)->snt_isn) {
 623                         NET_INC_STATS_BH(LINUX_MIB_OUTOFWINDOWICMPS);
 624                         goto out;
 625                 }
 626
 627                 inet_csk_reqsk_queue_drop(sk, req, prev);
 628                 goto out;
 629
 630         case TCP_SYN_SENT:
 631         case TCP_SYN_RECV:  /* Cannot happen.
 632                                It can, it SYNs are crossed. --ANK */
 633                 if (!sock_owned_by_user(sk)) {
 634                         TCP_INC_STATS_BH(TCP_MIB_ATTEMPTFAILS);
 635                         sk->sk_err = err;
 636                         sk->sk_error_report(sk);                /* Wake people up to see the error (see connect in sock.c) */
 637
 638                         tcp_done(sk);
 639                 } else
 640                         sk->sk_err_soft = err;
 641                 goto out;
 642         }
 643
 644         if (!sock_owned_by_user(sk) && np->recverr) {
 645                 sk->sk_err = err;
 646                 sk->sk_error_report(sk);
 647         } else
 648                 sk->sk_err_soft = err;
 649
 650 out:
 651         bh_unlock_sock(sk);
 652         sock_put(sk);
 653 }
 654
 655
 656 static int tcp_v6_send_synack(struct sock *sk, struct request_sock *req,
 657                               struct dst_entry *dst)
 658 {
 659         struct tcp6_request_sock *treq = tcp6_rsk(req);
 660         struct ipv6_pinfo *np = inet6_sk(sk);
 661         struct sk_buff * skb;
 662         struct ipv6_txoptions *opt = NULL;
 663         struct in6_addr * final_p = NULL, final;
 664         struct flowi fl;
 665         int err = -1;
 666
 667         memset(&fl, 0, sizeof(fl));
 668         fl.proto = IPPROTO_TCP;
 669         ipv6_addr_copy(&fl.fl6_dst, &treq->rmt_addr);
 670         ipv6_addr_copy(&fl.fl6_src, &treq->loc_addr);
 671         fl.fl6_flowlabel = 0;
 672         fl.oif = treq->iif;
 673         fl.fl_ip_dport = inet_rsk(req)->rmt_port;
 674         fl.fl_ip_sport = inet_sk(sk)->sport;
 675
 676         if (dst == NULL) {
 677                 opt = np->opt;
 678                 if (opt == NULL &&
 679                     np->rxopt.bits.osrcrt == 2 &&
 680                     treq->pktopts) {
 681                         struct sk_buff *pktopts = treq->pktopts;
 682                         struct inet6_skb_parm *rxopt = IP6CB(pktopts);
 683                         if (rxopt->srcrt)
 684                                 opt = ipv6_invert_rthdr(sk, (struct ipv6_rt_hdr*)(pktopts->nh.raw + rxopt->srcrt));
 685                 }
 686
 687                 if (opt && opt->srcrt) {
 688                         struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt;
 689                         ipv6_addr_copy(&final, &fl.fl6_dst);
 690                         ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
 691                         final_p = &final;
 692                 }
 693
 694                 err = ip6_dst_lookup(sk, &dst, &fl);
 695                 if (err)
 696                         goto done;
 697                 if (final_p)
 698                         ipv6_addr_copy(&fl.fl6_dst, final_p);
 699                 if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0)
 700                         goto done;
 701         }
 702
 703         skb = tcp_make_synack(sk, dst, req);
 704         if (skb) {
 705                 struct tcphdr *th = skb->h.th;
 706
 707                 th->check = tcp_v6_check(th, skb->len,
 708                                          &treq->loc_addr, &treq->rmt_addr,
 709                                          csum_partial((char *)th, skb->len, skb->csum));
 710
 711                 ipv6_addr_copy(&fl.fl6_dst, &treq->rmt_addr);
 712                 err = ip6_xmit(sk, skb, &fl, opt, 0);
 713                 if (err == NET_XMIT_CN)
 714                         err = 0;
 715         }
 716
 717 done:
 718         if (opt && opt != np->opt)
 719                 sock_kfree_s(sk, opt, opt->tot_len);
 720         return err;
 721 }
 722
 723 static void tcp_v6_reqsk_destructor(struct request_sock *req)
 724 {
 725         if (tcp6_rsk(req)->pktopts)
 726                 kfree_skb(tcp6_rsk(req)->pktopts);
 727 }
 728
 729 static struct request_sock_ops tcp6_request_sock_ops = {
 730         .family         =       AF_INET6,
 731         .obj_size       =       sizeof(struct tcp6_request_sock),
 732         .rtx_syn_ack    =       tcp_v6_send_synack,
 733         .send_ack       =       tcp_v6_reqsk_send_ack,
 734         .destructor     =       tcp_v6_reqsk_destructor,
 735         .send_reset     =       tcp_v6_send_reset
 736 };
 737
 738 static int ipv6_opt_accepted(struct sock *sk, struct sk_buff *skb)
 739 {
 740         struct ipv6_pinfo *np = inet6_sk(sk);
 741         struct inet6_skb_parm *opt = IP6CB(skb);
 742
 743         if (np->rxopt.all) {
 744                 if ((opt->hop && (np->rxopt.bits.hopopts || np->rxopt.bits.ohopopts)) ||
 745                     ((IPV6_FLOWINFO_MASK & *(u32*)skb->nh.raw) && np->rxopt.bits.rxflow) ||
 746                     (opt->srcrt && (np->rxopt.bits.srcrt || np->rxopt.bits.osrcrt)) ||
 747                     ((opt->dst1 || opt->dst0) && (np->rxopt.bits.dstopts || np->rxopt.bits.odstopts)))
 748                         return 1;
 749         }
 750         return 0;
 751 }
 752
 753
 754 static void tcp_v6_send_check(struct sock *sk, struct tcphdr *th, int len,
 755                               struct sk_buff *skb)
 756 {
 757         struct ipv6_pinfo *np = inet6_sk(sk);
 758
 759         if (skb->ip_summed == CHECKSUM_HW) {
 760                 th->check = ~csum_ipv6_magic(&np->saddr, &np->daddr, len, IPPROTO_TCP,  0);
 761                 skb->csum = offsetof(struct tcphdr, check);
 762         } else {
 763                 th->check = csum_ipv6_magic(&np->saddr, &np->daddr, len, IPPROTO_TCP,
 764                                             csum_partial((char *)th, th->doff<<2,
 765                                                          skb->csum));
 766         }
 767 }
 768
 769
 770 static void tcp_v6_send_reset(struct sk_buff *skb)
 771 {
 772         struct tcphdr *th = skb->h.th, *t1;
 773         struct sk_buff *buff;
 774         struct flowi fl;
 775
 776         if (th->rst)
 777                 return;
 778
 779         if (!ipv6_unicast_destination(skb))
 780                 return;
 781
 782         /*
 783          * We need to grab some memory, and put together an RST,
 784          * and then put it into the queue to be sent.
 785          */
 786
 787         buff = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + sizeof(struct tcphdr),
 788                          GFP_ATOMIC);
 789         if (buff == NULL)
 790                 return;
 791
 792         skb_reserve(buff, MAX_HEADER + sizeof(struct ipv6hdr) + sizeof(struct tcphdr));
 793
 794         t1 = (struct tcphdr *) skb_push(buff,sizeof(struct tcphdr));
 795
 796         /* Swap the send and the receive. */
 797         memset(t1, 0, sizeof(*t1));
 798         t1->dest = th->source;
 799         t1->source = th->dest;
 800         t1->doff = sizeof(*t1)/4;
 801         t1->rst = 1;
 802
 803         if(th->ack) {
 804                 t1->seq = th->ack_seq;
 805         } else {
 806                 t1->ack = 1;
 807                 t1->ack_seq = htonl(ntohl(th->seq) + th->syn + th->fin
 808                                     + skb->len - (th->doff<<2));
 809         }
 810
 811         buff->csum = csum_partial((char *)t1, sizeof(*t1), 0);
 812
 813         memset(&fl, 0, sizeof(fl));
 814         ipv6_addr_copy(&fl.fl6_dst, &skb->nh.ipv6h->saddr);
 815         ipv6_addr_copy(&fl.fl6_src, &skb->nh.ipv6h->daddr);
 816
 817         t1->check = csum_ipv6_magic(&fl.fl6_src, &fl.fl6_dst,
 818                                     sizeof(*t1), IPPROTO_TCP,
 819                                     buff->csum);
 820
 821         fl.proto = IPPROTO_TCP;
 822         fl.oif = inet6_iif(skb);
 823         fl.fl_ip_dport = t1->dest;
 824         fl.fl_ip_sport = t1->source;
 825
 826         /* sk = NULL, but it is safe for now. RST socket required. */
 827         if (!ip6_dst_lookup(NULL, &buff->dst, &fl)) {
 828
 829                 if (xfrm_lookup(&buff->dst, &fl, NULL, 0) >= 0) {
 830                         ip6_xmit(NULL, buff, &fl, NULL, 0);
 831                         TCP_INC_STATS_BH(TCP_MIB_OUTSEGS);
 832                         TCP_INC_STATS_BH(TCP_MIB_OUTRSTS);
 833                         return;
 834                 }
 835         }
 836
 837         kfree_skb(buff);
 838 }
 839
 840 static void tcp_v6_send_ack(struct sk_buff *skb, u32 seq, u32 ack, u32 win, u32 ts)
 841 {
 842         struct tcphdr *th = skb->h.th, *t1;
 843         struct sk_buff *buff;
 844         struct flowi fl;
 845         int tot_len = sizeof(struct tcphdr);
 846
 847         if (ts)
 848                 tot_len += 3*4;
 849
 850         buff = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + tot_len,
 851                          GFP_ATOMIC);
 852         if (buff == NULL)
 853                 return;
 854
 855         skb_reserve(buff, MAX_HEADER + sizeof(struct ipv6hdr) + tot_len);
 856
 857         t1 = (struct tcphdr *) skb_push(buff,tot_len);
 858
 859         /* Swap the send and the receive. */
 860         memset(t1, 0, sizeof(*t1));
 861         t1->dest = th->source;
 862         t1->source = th->dest;
 863         t1->doff = tot_len/4;
 864         t1->seq = htonl(seq);
 865         t1->ack_seq = htonl(ack);
 866         t1->ack = 1;
 867         t1->window = htons(win);
 868
 869         if (ts) {
 870                 u32 *ptr = (u32*)(t1 + 1);
 871                 *ptr++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) |
 872                                (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP);
 873                 *ptr++ = htonl(tcp_time_stamp);
 874                 *ptr = htonl(ts);
 875         }
 876
 877         buff->csum = csum_partial((char *)t1, tot_len, 0);
 878
 879         memset(&fl, 0, sizeof(fl));
 880         ipv6_addr_copy(&fl.fl6_dst, &skb->nh.ipv6h->saddr);
 881         ipv6_addr_copy(&fl.fl6_src, &skb->nh.ipv6h->daddr);
 882
 883         t1->check = csum_ipv6_magic(&fl.fl6_src, &fl.fl6_dst,
 884                                     tot_len, IPPROTO_TCP,
 885                                     buff->csum);
 886
 887         fl.proto = IPPROTO_TCP;
 888         fl.oif = inet6_iif(skb);
 889         fl.fl_ip_dport = t1->dest;
 890         fl.fl_ip_sport = t1->source;
 891
 892         if (!ip6_dst_lookup(NULL, &buff->dst, &fl)) {
 893                 if (xfrm_lookup(&buff->dst, &fl, NULL, 0) >= 0) {
 894                         ip6_xmit(NULL, buff, &fl, NULL, 0);
 895                         TCP_INC_STATS_BH(TCP_MIB_OUTSEGS);
 896                         return;
 897                 }
 898         }
 899
 900         kfree_skb(buff);
 901 }
 902
 903 static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb)
 904 {
 905         struct inet_timewait_sock *tw = inet_twsk(sk);
 906         const struct tcp_timewait_sock *tcptw = tcp_twsk(sk);
 907
 908         tcp_v6_send_ack(skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt,
 909                         tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale,
 910                         tcptw->tw_ts_recent);
 911
 912         inet_twsk_put(tw);
 913 }
 914
 915 static void tcp_v6_reqsk_send_ack(struct sk_buff *skb, struct request_sock *req)
 916 {
 917         tcp_v6_send_ack(skb, tcp_rsk(req)->snt_isn + 1, tcp_rsk(req)->rcv_isn + 1, req->rcv_wnd, req->ts_recent);
 918 }
 919
 920
 921 static struct sock *tcp_v6_hnd_req(struct sock *sk,struct sk_buff *skb)
 922 {
 923         struct request_sock *req, **prev;
 924         const struct tcphdr *th = skb->h.th;
 925         struct sock *nsk;
 926
 927         /* Find possible connection requests. */
 928         req = inet6_csk_search_req(sk, &prev, th->source,
 929                                    &skb->nh.ipv6h->saddr,
 930                                    &skb->nh.ipv6h->daddr, inet6_iif(skb));
 931         if (req)
 932                 return tcp_check_req(sk, skb, req, prev);
 933
 934         nsk = __inet6_lookup_established(&tcp_hashinfo, &skb->nh.ipv6h->saddr,
 935                                          th->source, &skb->nh.ipv6h->daddr,
 936                                          ntohs(th->dest), inet6_iif(skb));
 937
 938         if (nsk) {
 939                 if (nsk->sk_state != TCP_TIME_WAIT) {
 940                         bh_lock_sock(nsk);
 941                         return nsk;
 942                 }
 943                 inet_twsk_put((struct inet_timewait_sock *)nsk);
 944                 return NULL;
 945         }
 946
 947 #if 0 /*def CONFIG_SYN_COOKIES*/
 948         if (!th->rst && !th->syn && th->ack)
 949                 sk = cookie_v6_check(sk, skb, &(IPCB(skb)->opt));
 950 #endif
 951         return sk;
 952 }
 953
 954 /* FIXME: this is substantially similar to the ipv4 code.
 955  * Can some kind of merge be done? -- erics
 956  */
 957 static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
 958 {
 959         struct tcp6_request_sock *treq;
 960         struct ipv6_pinfo *np = inet6_sk(sk);
 961         struct tcp_options_received tmp_opt;
 962         struct tcp_sock *tp = tcp_sk(sk);
 963         struct request_sock *req = NULL;
 964         __u32 isn = TCP_SKB_CB(skb)->when;
 965
 966         if (skb->protocol == htons(ETH_P_IP))
 967                 return tcp_v4_conn_request(sk, skb);
 968
 969         if (!ipv6_unicast_destination(skb))
 970                 goto drop;
 971
 972         /*
 973          *      There are no SYN attacks on IPv6, yet...
 974          */
 975         if (inet_csk_reqsk_queue_is_full(sk) && !isn) {
 976                 if (net_ratelimit())
 977                         printk(KERN_INFO "TCPv6: dropping request, synflood is possible\n");
 978                 goto drop;
 979         }
 980
 981         if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1)
 982                 goto drop;
 983
 984         req = reqsk_alloc(&tcp6_request_sock_ops);
 985         if (req == NULL)
 986                 goto drop;
 987
 988         tcp_clear_options(&tmp_opt);
 989         tmp_opt.mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - sizeof(struct ipv6hdr);
 990         tmp_opt.user_mss = tp->rx_opt.user_mss;
 991
 992         tcp_parse_options(skb, &tmp_opt, 0);
 993
 994         tmp_opt.tstamp_ok = tmp_opt.saw_tstamp;
 995         tcp_openreq_init(req, &tmp_opt, skb);
 996
 997         treq = tcp6_rsk(req);
 998         ipv6_addr_copy(&treq->rmt_addr, &skb->nh.ipv6h->saddr);
 999         ipv6_addr_copy(&treq->loc_addr, &skb->nh.ipv6h->daddr);
1000         TCP_ECN_create_request(req, skb->h.th);
1001         treq->pktopts = NULL;
1002         if (ipv6_opt_accepted(sk, skb) ||
1003             np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
1004             np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) {
1005                 atomic_inc(&skb->users);
1006                 treq->pktopts = skb;
1007         }
1008         treq->iif = sk->sk_bound_dev_if;
1009
1010         /* So that link locals have meaning */
1011         if (!sk->sk_bound_dev_if &&
1012             ipv6_addr_type(&treq->rmt_addr) & IPV6_ADDR_LINKLOCAL)
1013                 treq->iif = inet6_iif(skb);
1014
1015         if (isn == 0)
1016                 isn = tcp_v6_init_sequence(sk,skb);
1017
1018         tcp_rsk(req)->snt_isn = isn;
1019
1020         if (tcp_v6_send_synack(sk, req, NULL))
1021                 goto drop;
1022
1023         inet6_csk_reqsk_queue_hash_add(sk, req, TCP_TIMEOUT_INIT);
1024         return 0;
1025
1026 drop:
1027         if (req)
1028                 reqsk_free(req);
1029
1030         TCP_INC_STATS_BH(TCP_MIB_ATTEMPTFAILS);
1031         return 0; /* don't send reset */
1032 }
1033
1034 static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
1035                                           struct request_sock *req,
1036                                           struct dst_entry *dst)
1037 {
1038         struct tcp6_request_sock *treq = tcp6_rsk(req);
1039         struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
1040         struct tcp6_sock *newtcp6sk;
1041         struct inet_sock *newinet;
1042         struct tcp_sock *newtp;
1043         struct sock *newsk;
1044         struct ipv6_txoptions *opt;
1045
1046         if (skb->protocol == htons(ETH_P_IP)) {
1047                 /*
1048                  *      v6 mapped
1049                  */
1050
1051                 newsk = tcp_v4_syn_recv_sock(sk, skb, req, dst);
1052
1053                 if (newsk == NULL)
1054                         return NULL;
1055
1056                 newtcp6sk = (struct tcp6_sock *)newsk;
1057                 inet_sk(newsk)->pinet6 = &newtcp6sk->inet6;
1058
1059                 newinet = inet_sk(newsk);
1060                 newnp = inet6_sk(newsk);
1061                 newtp = tcp_sk(newsk);
1062
1063                 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
1064
1065                 ipv6_addr_set(&newnp->daddr, 0, 0, htonl(0x0000FFFF),
1066                               newinet->daddr);
1067
1068                 ipv6_addr_set(&newnp->saddr, 0, 0, htonl(0x0000FFFF),
1069                               newinet->saddr);
1070
1071                 ipv6_addr_copy(&newnp->rcv_saddr, &newnp->saddr);
1072
1073                 newtp->af_specific = &ipv6_mapped;
1074                 newsk->sk_backlog_rcv = tcp_v4_do_rcv;
1075                 newnp->pktoptions  = NULL;
1076                 newnp->opt         = NULL;
1077                 newnp->mcast_oif   = inet6_iif(skb);
1078                 newnp->mcast_hops  = skb->nh.ipv6h->hop_limit;
1079
1080                 /*
1081                  * No need to charge this sock to the relevant IPv6 refcnt debug socks count
1082                  * here, tcp_create_openreq_child now does this for us, see the comment in
1083                  * that function for the gory details. -acme
1084                  */
1085
1086                 /* It is tricky place. Until this moment IPv4 tcp
1087                    worked with IPv6 af_tcp.af_specific.
1088                    Sync it now.
1089                  */
1090                 tcp_sync_mss(newsk, newtp->pmtu_cookie);
1091
1092                 return newsk;
1093         }
1094
1095         opt = np->opt;
1096
1097         if (sk_acceptq_is_full(sk))
1098                 goto out_overflow;
1099
1100         if (np->rxopt.bits.osrcrt == 2 &&
1101             opt == NULL && treq->pktopts) {
1102                 struct inet6_skb_parm *rxopt = IP6CB(treq->pktopts);
1103                 if (rxopt->srcrt)
1104                         opt = ipv6_invert_rthdr(sk, (struct ipv6_rt_hdr *)(treq->pktopts->nh.raw + rxopt->srcrt));
1105         }
1106
1107         if (dst == NULL) {
1108                 struct in6_addr *final_p = NULL, final;
1109                 struct flowi fl;
1110
1111                 memset(&fl, 0, sizeof(fl));
1112                 fl.proto = IPPROTO_TCP;
1113                 ipv6_addr_copy(&fl.fl6_dst, &treq->rmt_addr);
1114                 if (opt && opt->srcrt) {
1115                         struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt;
1116                         ipv6_addr_copy(&final, &fl.fl6_dst);
1117                         ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
1118                         final_p = &final;
1119                 }
1120                 ipv6_addr_copy(&fl.fl6_src, &treq->loc_addr);
1121                 fl.oif = sk->sk_bound_dev_if;
1122                 fl.fl_ip_dport = inet_rsk(req)->rmt_port;
1123                 fl.fl_ip_sport = inet_sk(sk)->sport;
1124
1125                 if (ip6_dst_lookup(sk, &dst, &fl))
1126                         goto out;
1127
1128                 if (final_p)
1129                         ipv6_addr_copy(&fl.fl6_dst, final_p);
1130
1131                 if ((xfrm_lookup(&dst, &fl, sk, 0)) < 0)
1132                         goto out;
1133         }
1134
1135         newsk = tcp_create_openreq_child(sk, req, skb);
1136         if (newsk == NULL)
1137                 goto out;
1138
1139         /*
1140          * No need to charge this sock to the relevant IPv6 refcnt debug socks
1141          * count here, tcp_create_openreq_child now does this for us, see the
1142          * comment in that function for the gory details. -acme
1143          */
1144
1145         ip6_dst_store(newsk, dst, NULL);
1146         newsk->sk_route_caps = dst->dev->features &
1147                 ~(NETIF_F_IP_CSUM | NETIF_F_TSO);
1148
1149         newtcp6sk = (struct tcp6_sock *)newsk;
1150         inet_sk(newsk)->pinet6 = &newtcp6sk->inet6;
1151
1152         newtp = tcp_sk(newsk);
1153         newinet = inet_sk(newsk);
1154         newnp = inet6_sk(newsk);
1155
1156         memcpy(newnp, np, sizeof(struct ipv6_pinfo));
1157
1158         ipv6_addr_copy(&newnp->daddr, &treq->rmt_addr);
1159         ipv6_addr_copy(&newnp->saddr, &treq->loc_addr);
1160         ipv6_addr_copy(&newnp->rcv_saddr, &treq->loc_addr);
1161         newsk->sk_bound_dev_if = treq->iif;
1162
1163         /* Now IPv6 options...
1164
1165            First: no IPv4 options.
1166          */
1167         newinet->opt = NULL;
1168
1169         /* Clone RX bits */
1170         newnp->rxopt.all = np->rxopt.all;
1171
1172         /* Clone pktoptions received with SYN */
1173         newnp->pktoptions = NULL;
1174         if (treq->pktopts != NULL) {
1175                 newnp->pktoptions = skb_clone(treq->pktopts, GFP_ATOMIC);
1176                 kfree_skb(treq->pktopts);
1177                 treq->pktopts = NULL;
1178                 if (newnp->pktoptions)
1179                         skb_set_owner_r(newnp->pktoptions, newsk);
1180         }
1181         newnp->opt        = NULL;
1182         newnp->mcast_oif  = inet6_iif(skb);
1183         newnp->mcast_hops = skb->nh.ipv6h->hop_limit;
1184
1185         /* Clone native IPv6 options from listening socket (if any)
1186
1187            Yes, keeping reference count would be much more clever,
1188            but we make one more one thing there: reattach optmem
1189            to newsk.
1190          */
1191         if (opt) {
1192                 newnp->opt = ipv6_dup_options(newsk, opt);
1193                 if (opt != np->opt)
1194                         sock_kfree_s(sk, opt, opt->tot_len);
1195         }
1196
1197         newtp->ext_header_len = 0;
1198         if (newnp->opt)
1199                 newtp->ext_header_len = newnp->opt->opt_nflen +
1200                                         newnp->opt->opt_flen;
1201
1202         tcp_sync_mss(newsk, dst_mtu(dst));
1203         newtp->advmss = dst_metric(dst, RTAX_ADVMSS);
1204         tcp_initialize_rcv_mss(newsk);
1205
1206         newinet->daddr = newinet->saddr = newinet->rcv_saddr = LOOPBACK4_IPV6;
1207
1208         __inet6_hash(&tcp_hashinfo, newsk);
1209         inet_inherit_port(&tcp_hashinfo, sk, newsk);
1210
1211         return newsk;
1212
1213 out_overflow:
1214         NET_INC_STATS_BH(LINUX_MIB_LISTENOVERFLOWS);
1215 out:
1216         NET_INC_STATS_BH(LINUX_MIB_LISTENDROPS);
1217         if (opt && opt != np->opt)
1218                 sock_kfree_s(sk, opt, opt->tot_len);
1219         dst_release(dst);
1220         return NULL;
1221 }
1222
1223 static int tcp_v6_checksum_init(struct sk_buff *skb)
1224 {
1225         if (skb->ip_summed == CHECKSUM_HW) {
1226                 if (!tcp_v6_check(skb->h.th,skb->len,&skb->nh.ipv6h->saddr,
1227                                   &skb->nh.ipv6h->daddr,skb->csum)) {
1228                         skb->ip_summed = CHECKSUM_UNNECESSARY;
1229                         return 0;
1230                 }
1231         }
1232
1233         skb->csum = ~tcp_v6_check(skb->h.th,skb->len,&skb->nh.ipv6h->saddr,
1234                                   &skb->nh.ipv6h->daddr, 0);
1235
1236         if (skb->len <= 76) {
1237                 return __skb_checksum_complete(skb);
1238         }
1239         return 0;
1240 }
1241
1242 /* The socket must have it's spinlock held when we get
1243  * here.
1244  *
1245  * We have a potential double-lock case here, so even when
1246  * doing backlog processing we use the BH locking scheme.
1247  * This is because we cannot sleep with the original spinlock
1248  * held.
1249  */
1250 static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
1251 {
1252         struct ipv6_pinfo *np = inet6_sk(sk);
1253         struct tcp_sock *tp;
1254         struct sk_buff *opt_skb = NULL;
1255
1256         /* Imagine: socket is IPv6. IPv4 packet arrives,
1257            goes to IPv4 receive handler and backlogged.
1258            From backlog it always goes here. Kerboom...
1259            Fortunately, tcp_rcv_established and rcv_established
1260            handle them correctly, but it is not case with
1261            tcp_v6_hnd_req and tcp_v6_send_reset().   --ANK
1262          */
1263
1264         if (skb->protocol == htons(ETH_P_IP))
1265                 return tcp_v4_do_rcv(sk, skb);
1266
1267         if (sk_filter(sk, skb, 0))
1268                 goto discard;
1269
1270         /*
1271          *      socket locking is here for SMP purposes as backlog rcv
1272          *      is currently called with bh processing disabled.
1273          */
1274
1275         /* Do Stevens' IPV6_PKTOPTIONS.
1276
1277            Yes, guys, it is the only place in our code, where we
1278            may make it not affecting IPv4.
1279            The rest of code is protocol independent,
1280            and I do not like idea to uglify IPv4.
1281
1282            Actually, all the idea behind IPV6_PKTOPTIONS
1283            looks not very well thought. For now we latch
1284            options, received in the last packet, enqueued
1285            by tcp. Feel free to propose better solution.
1286                                                --ANK (980728)
1287          */
1288         if (np->rxopt.all)
1289                 opt_skb = skb_clone(skb, GFP_ATOMIC);
1290
1291         if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */
1292                 TCP_CHECK_TIMER(sk);
1293                 if (tcp_rcv_established(sk, skb, skb->h.th, skb->len))
1294                         goto reset;
1295                 TCP_CHECK_TIMER(sk);
1296                 if (opt_skb)
1297                         goto ipv6_pktoptions;
1298                 return 0;
1299         }
1300
1301         if (skb->len < (skb->h.th->doff<<2) || tcp_checksum_complete(skb))
1302                 goto csum_err;
1303
1304         if (sk->sk_state == TCP_LISTEN) {
1305                 struct sock *nsk = tcp_v6_hnd_req(sk, skb);
1306                 if (!nsk)
1307                         goto discard;
1308
1309                 /*
1310                  * Queue it on the new socket if the new socket is active,
1311                  * otherwise we just shortcircuit this and continue with
1312                  * the new socket..
1313                  */
1314                 if(nsk != sk) {
1315                         if (tcp_child_process(sk, nsk, skb))
1316                                 goto reset;
1317                         if (opt_skb)
1318                                 __kfree_skb(opt_skb);
1319                         return 0;
1320                 }
1321         }
1322
1323         TCP_CHECK_TIMER(sk);
1324         if (tcp_rcv_state_process(sk, skb, skb->h.th, skb->len))
1325                 goto reset;
1326         TCP_CHECK_TIMER(sk);
1327         if (opt_skb)
1328                 goto ipv6_pktoptions;
1329         return 0;
1330
1331 reset:
1332         tcp_v6_send_reset(skb);
1333 discard:
1334         if (opt_skb)
1335                 __kfree_skb(opt_skb);
1336         kfree_skb(skb);
1337         return 0;
1338 csum_err:
1339         TCP_INC_STATS_BH(TCP_MIB_INERRS);
1340         goto discard;
1341
1342
1343 ipv6_pktoptions:
1344         /* Do you ask, what is it?
1345
1346            1. skb was enqueued by tcp.
1347            2. skb is added to tail of read queue, rather than out of order.
1348            3. socket is not in passive state.
1349            4. Finally, it really contains options, which user wants to receive.
1350          */
1351         tp = tcp_sk(sk);
1352         if (TCP_SKB_CB(opt_skb)->end_seq == tp->rcv_nxt &&
1353             !((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))) {
1354                 if (np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo)
1355                         np->mcast_oif = inet6_iif(opt_skb);
1356                 if (np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim)
1357                         np->mcast_hops = opt_skb->nh.ipv6h->hop_limit;
1358                 if (ipv6_opt_accepted(sk, opt_skb)) {
1359                         skb_set_owner_r(opt_skb, sk);
1360                         opt_skb = xchg(&np->pktoptions, opt_skb);
1361                 } else {
1362                         __kfree_skb(opt_skb);
1363                         opt_skb = xchg(&np->pktoptions, NULL);
1364                 }
1365         }
1366
1367         if (opt_skb)
1368                 kfree_skb(opt_skb);
1369         return 0;
1370 }
1371
1372 static int tcp_v6_rcv(struct sk_buff **pskb, unsigned int *nhoffp)
1373 {
1374         struct sk_buff *skb = *pskb;
1375         struct tcphdr *th;
1376         struct sock *sk;
1377         int ret;
1378
1379         if (skb->pkt_type != PACKET_HOST)
1380                 goto discard_it;
1381
1382         /*
1383          *      Count it even if it's bad.
1384          */
1385         TCP_INC_STATS_BH(TCP_MIB_INSEGS);
1386
1387         if (!pskb_may_pull(skb, sizeof(struct tcphdr)))
1388                 goto discard_it;
1389
1390         th = skb->h.th;
1391
1392         if (th->doff < sizeof(struct tcphdr)/4)
1393                 goto bad_packet;
1394         if (!pskb_may_pull(skb, th->doff*4))
1395                 goto discard_it;
1396
1397         if ((skb->ip_summed != CHECKSUM_UNNECESSARY &&
1398              tcp_v6_checksum_init(skb)))
1399                 goto bad_packet;
1400
1401         th = skb->h.th;
1402         TCP_SKB_CB(skb)->seq = ntohl(th->seq);
1403         TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin +
1404                                     skb->len - th->doff*4);
1405         TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq);
1406         TCP_SKB_CB(skb)->when = 0;
1407         TCP_SKB_CB(skb)->flags = ipv6_get_dsfield(skb->nh.ipv6h);
1408         TCP_SKB_CB(skb)->sacked = 0;
1409
1410         sk = __inet6_lookup(&tcp_hashinfo, &skb->nh.ipv6h->saddr, th->source,
1411                             &skb->nh.ipv6h->daddr, ntohs(th->dest),
1412                             inet6_iif(skb));
1413
1414         if (!sk)
1415                 goto no_tcp_socket;
1416
1417 process:
1418         if (sk->sk_state == TCP_TIME_WAIT)
1419                 goto do_time_wait;
1420
1421         if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
1422                 goto discard_and_relse;
1423
1424         if (sk_filter(sk, skb, 0))
1425                 goto discard_and_relse;
1426
1427         skb->dev = NULL;
1428
1429         bh_lock_sock(sk);
1430         ret = 0;
1431         if (!sock_owned_by_user(sk)) {
1432                 if (!tcp_prequeue(sk, skb))
1433                         ret = tcp_v6_do_rcv(sk, skb);
1434         } else
1435                 sk_add_backlog(sk, skb);
1436         bh_unlock_sock(sk);
1437
1438         sock_put(sk);
1439         return ret ? -1 : 0;
1440
1441 no_tcp_socket:
1442         if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
1443                 goto discard_it;
1444
1445         if (skb->len < (th->doff<<2) || tcp_checksum_complete(skb)) {
1446 bad_packet:
1447                 TCP_INC_STATS_BH(TCP_MIB_INERRS);
1448         } else {
1449                 tcp_v6_send_reset(skb);
1450         }
1451
1452 discard_it:
1453
1454         /*
1455          *      Discard frame
1456          */
1457
1458         kfree_skb(skb);
1459         return 0;
1460
1461 discard_and_relse:
1462         sock_put(sk);
1463         goto discard_it;
1464
1465 do_time_wait:
1466         if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
1467                 inet_twsk_put((struct inet_timewait_sock *)sk);
1468                 goto discard_it;
1469         }
1470
1471         if (skb->len < (th->doff<<2) || tcp_checksum_complete(skb)) {
1472                 TCP_INC_STATS_BH(TCP_MIB_INERRS);
1473                 inet_twsk_put((struct inet_timewait_sock *)sk);
1474                 goto discard_it;
1475         }
1476
1477         switch (tcp_timewait_state_process((struct inet_timewait_sock *)sk,
1478                                            skb, th)) {
1479         case TCP_TW_SYN:
1480         {
1481                 struct sock *sk2;
1482
1483                 sk2 = inet6_lookup_listener(&tcp_hashinfo,
1484                                             &skb->nh.ipv6h->daddr,
1485                                             ntohs(th->dest), inet6_iif(skb));
1486                 if (sk2 != NULL) {
1487                         struct inet_timewait_sock *tw = inet_twsk(sk);
1488                         inet_twsk_deschedule(tw, &tcp_death_row);
1489                         inet_twsk_put(tw);
1490                         sk = sk2;
1491                         goto process;
1492                 }
1493                 /* Fall through to ACK */
1494         }
1495         case TCP_TW_ACK:
1496                 tcp_v6_timewait_ack(sk, skb);
1497                 break;
1498         case TCP_TW_RST:
1499                 goto no_tcp_socket;
1500         case TCP_TW_SUCCESS:;
1501         }
1502         goto discard_it;
1503 }
1504
1505 static int tcp_v6_rebuild_header(struct sock *sk)
1506 {
1507         int err;
1508         struct dst_entry *dst;
1509         struct ipv6_pinfo *np = inet6_sk(sk);
1510
1511         dst = __sk_dst_check(sk, np->dst_cookie);
1512
1513         if (dst == NULL) {
1514                 struct inet_sock *inet = inet_sk(sk);
1515                 struct in6_addr *final_p = NULL, final;
1516                 struct flowi fl;
1517
1518                 memset(&fl, 0, sizeof(fl));
1519                 fl.proto = IPPROTO_TCP;
1520                 ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
1521                 ipv6_addr_copy(&fl.fl6_src, &np->saddr);
1522                 fl.fl6_flowlabel = np->flow_label;
1523                 fl.oif = sk->sk_bound_dev_if;
1524                 fl.fl_ip_dport = inet->dport;
1525                 fl.fl_ip_sport = inet->sport;
1526
1527                 if (np->opt && np->opt->srcrt) {
1528                         struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
1529                         ipv6_addr_copy(&final, &fl.fl6_dst);
1530                         ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
1531                         final_p = &final;
1532                 }
1533
1534                 err = ip6_dst_lookup(sk, &dst, &fl);
1535                 if (err) {
1536                         sk->sk_route_caps = 0;
1537                         return err;
1538                 }
1539                 if (final_p)
1540                         ipv6_addr_copy(&fl.fl6_dst, final_p);
1541
1542                 if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) {
1543                         sk->sk_err_soft = -err;
1544                         return err;
1545                 }
1546
1547                 ip6_dst_store(sk, dst, NULL);
1548                 sk->sk_route_caps = dst->dev->features &
1549                         ~(NETIF_F_IP_CSUM | NETIF_F_TSO);
1550         }
1551
1552         return 0;
1553 }
1554
1555 static int tcp_v6_xmit(struct sk_buff *skb, int ipfragok)
1556 {
1557         struct sock *sk = skb->sk;
1558         struct inet_sock *inet = inet_sk(sk);
1559         struct ipv6_pinfo *np = inet6_sk(sk);
1560         struct flowi fl;
1561         struct dst_entry *dst;
1562         struct in6_addr *final_p = NULL, final;
1563
1564         memset(&fl, 0, sizeof(fl));
1565         fl.proto = IPPROTO_TCP;
1566         ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
1567         ipv6_addr_copy(&fl.fl6_src, &np->saddr);
1568         fl.fl6_flowlabel = np->flow_label;
1569         IP6_ECN_flow_xmit(sk, fl.fl6_flowlabel);
1570         fl.oif = sk->sk_bound_dev_if;
1571         fl.fl_ip_sport = inet->sport;
1572         fl.fl_ip_dport = inet->dport;
1573
1574         if (np->opt && np->opt->srcrt) {
1575                 struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
1576                 ipv6_addr_copy(&final, &fl.fl6_dst);
1577                 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
1578                 final_p = &final;
1579         }
1580
1581         dst = __sk_dst_check(sk, np->dst_cookie);
1582
1583         if (dst == NULL) {
1584                 int err = ip6_dst_lookup(sk, &dst, &fl);
1585
1586                 if (err) {
1587                         sk->sk_err_soft = -err;
1588                         return err;
1589                 }
1590
1591                 if (final_p)
1592                         ipv6_addr_copy(&fl.fl6_dst, final_p);
1593
1594                 if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) {
1595                         sk->sk_route_caps = 0;
1596                         return err;
1597                 }
1598
1599                 ip6_dst_store(sk, dst, NULL);
1600                 sk->sk_route_caps = dst->dev->features &
1601                         ~(NETIF_F_IP_CSUM | NETIF_F_TSO);
1602         }
1603
1604         skb->dst = dst_clone(dst);
1605
1606         /* Restore final destination back after routing done */
1607         ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
1608
1609         return ip6_xmit(sk, skb, &fl, np->opt, 0);
1610 }
1611
1612 static void v6_addr2sockaddr(struct sock *sk, struct sockaddr * uaddr)
1613 {
1614         struct ipv6_pinfo *np = inet6_sk(sk);
1615         struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) uaddr;
1616
1617         sin6->sin6_family = AF_INET6;
1618         ipv6_addr_copy(&sin6->sin6_addr, &np->daddr);
1619         sin6->sin6_port = inet_sk(sk)->dport;
1620         /* We do not store received flowlabel for TCP */
1621         sin6->sin6_flowinfo = 0;
1622         sin6->sin6_scope_id = 0;
1623         if (sk->sk_bound_dev_if &&
1624             ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
1625                 sin6->sin6_scope_id = sk->sk_bound_dev_if;
1626 }
1627
1628 static int tcp_v6_remember_stamp(struct sock *sk)
1629 {
1630         /* Alas, not yet... */
1631         return 0;
1632 }
1633
1634 static struct tcp_func ipv6_specific = {
1635         .queue_xmit     =       tcp_v6_xmit,
1636         .send_check     =       tcp_v6_send_check,
1637         .rebuild_header =       tcp_v6_rebuild_header,
1638         .conn_request   =       tcp_v6_conn_request,
1639         .syn_recv_sock  =       tcp_v6_syn_recv_sock,
1640         .remember_stamp =       tcp_v6_remember_stamp,
1641         .net_header_len =       sizeof(struct ipv6hdr),
1642
1643         .setsockopt     =       ipv6_setsockopt,
1644         .getsockopt     =       ipv6_getsockopt,
1645         .addr2sockaddr  =       v6_addr2sockaddr,
1646         .sockaddr_len   =       sizeof(struct sockaddr_in6)
1647 };
1648
1649 /*
1650  *      TCP over IPv4 via INET6 API
1651  */
1652
1653 static struct tcp_func ipv6_mapped = {
1654         .queue_xmit     =       ip_queue_xmit,
1655         .send_check     =       tcp_v4_send_check,
1656         .rebuild_header =       inet_sk_rebuild_header,
1657         .conn_request   =       tcp_v6_conn_request,
1658         .syn_recv_sock  =       tcp_v6_syn_recv_sock,
1659         .remember_stamp =       tcp_v4_remember_stamp,
1660         .net_header_len =       sizeof(struct iphdr),
1661
1662         .setsockopt     =       ipv6_setsockopt,
1663         .getsockopt     =       ipv6_getsockopt,
1664         .addr2sockaddr  =       v6_addr2sockaddr,
1665         .sockaddr_len   =       sizeof(struct sockaddr_in6)
1666 };
1667
1668
1669
1670 /* NOTE: A lot of things set to zero explicitly by call to
1671  *       sk_alloc() so need not be done here.
1672  */
1673 static int tcp_v6_init_sock(struct sock *sk)
1674 {
1675         struct inet_connection_sock *icsk = inet_csk(sk);
1676         struct tcp_sock *tp = tcp_sk(sk);
1677
1678         skb_queue_head_init(&tp->out_of_order_queue);
1679         tcp_init_xmit_timers(sk);
1680         tcp_prequeue_init(tp);
1681
1682         icsk->icsk_rto = TCP_TIMEOUT_INIT;
1683         tp->mdev = TCP_TIMEOUT_INIT;
1684
1685         /* So many TCP implementations out there (incorrectly) count the
1686          * initial SYN frame in their delayed-ACK and congestion control
1687          * algorithms that we must have the following bandaid to talk
1688          * efficiently to them.  -DaveM
1689          */
1690         tp->snd_cwnd = 2;
1691
1692         /* See draft-stevens-tcpca-spec-01 for discussion of the
1693          * initialization of these values.
1694          */
1695         tp->snd_ssthresh = 0x7fffffff;
1696         tp->snd_cwnd_clamp = ~0;
1697         tp->mss_cache = 536;
1698
1699         tp->reordering = sysctl_tcp_reordering;
1700
1701         sk->sk_state = TCP_CLOSE;
1702
1703         tp->af_specific = &ipv6_specific;
1704         icsk->icsk_ca_ops = &tcp_init_congestion_ops;
1705         sk->sk_write_space = sk_stream_write_space;
1706         sock_set_flag(sk, SOCK_USE_WRITE_QUEUE);
1707
1708         sk->sk_sndbuf = sysctl_tcp_wmem[1];
1709         sk->sk_rcvbuf = sysctl_tcp_rmem[1];
1710
1711         atomic_inc(&tcp_sockets_allocated);
1712
1713         return 0;
1714 }
1715
1716 static int tcp_v6_destroy_sock(struct sock *sk)
1717 {
1718         tcp_v4_destroy_sock(sk);
1719         return inet6_destroy_sock(sk);
1720 }
1721
1722 /* Proc filesystem TCPv6 sock list dumping. */
1723 static void get_openreq6(struct seq_file *seq,
1724                          struct sock *sk, struct request_sock *req, int i, int uid)
1725 {
1726         struct in6_addr *dest, *src;
1727         int ttd = req->expires - jiffies;
1728
1729         if (ttd < 0)
1730                 ttd = 0;
1731
1732         src = &tcp6_rsk(req)->loc_addr;
1733         dest = &tcp6_rsk(req)->rmt_addr;
1734         seq_printf(seq,
1735                    "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1736                    "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %p\n",
1737                    i,
1738                    src->s6_addr32[0], src->s6_addr32[1],
1739                    src->s6_addr32[2], src->s6_addr32[3],
1740                    ntohs(inet_sk(sk)->sport),
1741                    dest->s6_addr32[0], dest->s6_addr32[1],
1742                    dest->s6_addr32[2], dest->s6_addr32[3],
1743                    ntohs(inet_rsk(req)->rmt_port),
1744                    TCP_SYN_RECV,
1745                    0,0, /* could print option size, but that is af dependent. */
1746                    1,   /* timers active (only the expire timer) */
1747                    jiffies_to_clock_t(ttd),
1748                    req->retrans,
1749                    uid,
1750                    0,  /* non standard timer */
1751                    0, /* open_requests have no inode */
1752                    0, req);
1753 }
1754
1755 static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i)
1756 {
1757         struct in6_addr *dest, *src;
1758         __u16 destp, srcp;
1759         int timer_active;
1760         unsigned long timer_expires;
1761         struct inet_sock *inet = inet_sk(sp);
1762         struct tcp_sock *tp = tcp_sk(sp);
1763         const struct inet_connection_sock *icsk = inet_csk(sp);
1764         struct ipv6_pinfo *np = inet6_sk(sp);
1765
1766         dest  = &np->daddr;
1767         src   = &np->rcv_saddr;
1768         destp = ntohs(inet->dport);
1769         srcp  = ntohs(inet->sport);
1770
1771         if (icsk->icsk_pending == ICSK_TIME_RETRANS) {
1772                 timer_active    = 1;
1773                 timer_expires   = icsk->icsk_timeout;
1774         } else if (icsk->icsk_pending == ICSK_TIME_PROBE0) {
1775                 timer_active    = 4;
1776                 timer_expires   = icsk->icsk_timeout;
1777         } else if (timer_pending(&sp->sk_timer)) {
1778                 timer_active    = 2;
1779                 timer_expires   = sp->sk_timer.expires;
1780         } else {
1781                 timer_active    = 0;
1782                 timer_expires = jiffies;
1783         }
1784
1785         seq_printf(seq,
1786                    "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1787                    "%02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %p %u %u %u %u %d\n",
1788                    i,
1789                    src->s6_addr32[0], src->s6_addr32[1],
1790                    src->s6_addr32[2], src->s6_addr32[3], srcp,
1791                    dest->s6_addr32[0], dest->s6_addr32[1],
1792                    dest->s6_addr32[2], dest->s6_addr32[3], destp,
1793                    sp->sk_state,
1794                    tp->write_seq-tp->snd_una, tp->rcv_nxt-tp->copied_seq,
1795                    timer_active,
1796                    jiffies_to_clock_t(timer_expires - jiffies),
1797                    icsk->icsk_retransmits,
1798                    sock_i_uid(sp),
1799                    icsk->icsk_probes_out,
1800                    sock_i_ino(sp),
1801                    atomic_read(&sp->sk_refcnt), sp,
1802                    icsk->icsk_rto,
1803                    icsk->icsk_ack.ato,
1804                    (icsk->icsk_ack.quick << 1 ) | icsk->icsk_ack.pingpong,
1805                    tp->snd_cwnd, tp->snd_ssthresh>=0xFFFF?-1:tp->snd_ssthresh
1806                    );
1807 }
1808
1809 static void get_timewait6_sock(struct seq_file *seq,
1810                                struct inet_timewait_sock *tw, int i)
1811 {
1812         struct in6_addr *dest, *src;
1813         __u16 destp, srcp;
1814         struct tcp6_timewait_sock *tcp6tw = tcp6_twsk((struct sock *)tw);
1815         int ttd = tw->tw_ttd - jiffies;
1816
1817         if (ttd < 0)
1818                 ttd = 0;
1819
1820         dest = &tcp6tw->tw_v6_daddr;
1821         src  = &tcp6tw->tw_v6_rcv_saddr;
1822         destp = ntohs(tw->tw_dport);
1823         srcp  = ntohs(tw->tw_sport);
1824
1825         seq_printf(seq,
1826                    "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1827                    "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %p\n",
1828                    i,
1829                    src->s6_addr32[0], src->s6_addr32[1],
1830                    src->s6_addr32[2], src->s6_addr32[3], srcp,
1831                    dest->s6_addr32[0], dest->s6_addr32[1],
1832                    dest->s6_addr32[2], dest->s6_addr32[3], destp,
1833                    tw->tw_substate, 0, 0,
1834                    3, jiffies_to_clock_t(ttd), 0, 0, 0, 0,
1835                    atomic_read(&tw->tw_refcnt), tw);
1836 }
1837
1838 #ifdef CONFIG_PROC_FS
1839 static int tcp6_seq_show(struct seq_file *seq, void *v)
1840 {
1841         struct tcp_iter_state *st;
1842
1843         if (v == SEQ_START_TOKEN) {
1844                 seq_puts(seq,
1845                          "  sl  "
1846                          "local_address                         "
1847                          "remote_address                        "
1848                          "st tx_queue rx_queue tr tm->when retrnsmt"
1849                          "   uid  timeout inode\n");
1850                 goto out;
1851         }
1852         st = seq->private;
1853
1854         switch (st->state) {
1855         case TCP_SEQ_STATE_LISTENING:
1856         case TCP_SEQ_STATE_ESTABLISHED:
1857                 get_tcp6_sock(seq, v, st->num);
1858                 break;
1859         case TCP_SEQ_STATE_OPENREQ:
1860                 get_openreq6(seq, st->syn_wait_sk, v, st->num, st->uid);
1861                 break;
1862         case TCP_SEQ_STATE_TIME_WAIT:
1863                 get_timewait6_sock(seq, v, st->num);
1864                 break;
1865         }
1866 out:
1867         return 0;
1868 }
1869
1870 static struct file_operations tcp6_seq_fops;
1871 static struct tcp_seq_afinfo tcp6_seq_afinfo = {
1872         .owner          = THIS_MODULE,
1873         .name           = "tcp6",
1874         .family         = AF_INET6,
1875         .seq_show       = tcp6_seq_show,
1876         .seq_fops       = &tcp6_seq_fops,
1877 };
1878
1879 int __init tcp6_proc_init(void)
1880 {
1881         return tcp_proc_register(&tcp6_seq_afinfo);
1882 }
1883
1884 void tcp6_proc_exit(void)
1885 {
1886         tcp_proc_unregister(&tcp6_seq_afinfo);
1887 }
1888 #endif
1889
1890 struct proto tcpv6_prot = {
1891         .name                   = "TCPv6",
1892         .owner                  = THIS_MODULE,
1893         .close                  = tcp_close,
1894         .connect                = tcp_v6_connect,
1895         .disconnect             = tcp_disconnect,
1896         .accept                 = inet_csk_accept,
1897         .ioctl                  = tcp_ioctl,
1898         .init                   = tcp_v6_init_sock,
1899         .destroy                = tcp_v6_destroy_sock,
1900         .shutdown               = tcp_shutdown,
1901         .setsockopt             = tcp_setsockopt,
1902         .getsockopt             = tcp_getsockopt,
1903         .sendmsg                = tcp_sendmsg,
1904         .recvmsg                = tcp_recvmsg,
1905         .backlog_rcv            = tcp_v6_do_rcv,
1906         .hash                   = tcp_v6_hash,
1907         .unhash                 = tcp_unhash,
1908         .get_port               = tcp_v6_get_port,
1909         .enter_memory_pressure  = tcp_enter_memory_pressure,
1910         .sockets_allocated      = &tcp_sockets_allocated,
1911         .memory_allocated       = &tcp_memory_allocated,
1912         .memory_pressure        = &tcp_memory_pressure,
1913         .orphan_count           = &tcp_orphan_count,
1914         .sysctl_mem             = sysctl_tcp_mem,
1915         .sysctl_wmem            = sysctl_tcp_wmem,
1916         .sysctl_rmem            = sysctl_tcp_rmem,
1917         .max_header             = MAX_TCP_HEADER,
1918         .obj_size               = sizeof(struct tcp6_sock),
1919         .twsk_obj_size          = sizeof(struct tcp6_timewait_sock),
1920         .rsk_prot               = &tcp6_request_sock_ops,
1921 };
1922
1923 static struct inet6_protocol tcpv6_protocol = {
1924         .handler        =       tcp_v6_rcv,
1925         .err_handler    =       tcp_v6_err,
1926         .flags          =       INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1927 };
1928
1929 static struct inet_protosw tcpv6_protosw = {
1930         .type           =       SOCK_STREAM,
1931         .protocol       =       IPPROTO_TCP,
1932         .prot           =       &tcpv6_prot,
1933         .ops            =       &inet6_stream_ops,
1934         .capability     =       -1,
1935         .no_check       =       0,
1936         .flags          =       INET_PROTOSW_PERMANENT,
1937 };
1938
1939 void __init tcpv6_init(void)
1940 {
1941         /* register inet6 protocol */
1942         if (inet6_add_protocol(&tcpv6_protocol, IPPROTO_TCP) < 0)
1943                 printk(KERN_ERR "tcpv6_init: Could not register protocol\n");
1944         inet6_register_protosw(&tcpv6_protosw);
1945 }