net/sctp/ipv6.c

   1 /* SCTP kernel implementation
   2  * (C) Copyright IBM Corp. 2002, 2004
   3  * Copyright (c) 2001 Nokia, Inc.
   4  * Copyright (c) 2001 La Monte H.P. Yarroll
   5  * Copyright (c) 2002-2003 Intel Corp.
   6  *
   7  * This file is part of the SCTP kernel implementation
   8  *
   9  * SCTP over IPv6.
  10  *
  11  * This SCTP implementation is free software;
  12  * you can redistribute it and/or modify it under the terms of
  13  * the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2, or (at your option)
  15  * any later version.
  16  *
  17  * This SCTP implementation is distributed in the hope that it
  18  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
  19  *                 ************************
  20  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  21  * See the GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with GNU CC; see the file COPYING.  If not, see
  25  * <http://www.gnu.org/licenses/>.
  26  *
  27  * Please send any bug reports or fixes you make to the
  28  * email address(es):
  29  *    lksctp developers <linux-sctp@vger.kernel.org>
  30  *
  31  * Written or modified by:
  32  *    Le Yanqun             <yanqun.le@nokia.com>
  33  *    Hui Huang             <hui.huang@nokia.com>
  34  *    La Monte H.P. Yarroll <piggy@acm.org>
  35  *    Sridhar Samudrala     <sri@us.ibm.com>
  36  *    Jon Grimm             <jgrimm@us.ibm.com>
  37  *    Ardelle Fan           <ardelle.fan@intel.com>
  38  *
  39  * Based on:
  40  *      linux/net/ipv6/tcp_ipv6.c
  41  */
  42
  43 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  44
  45 #include <linux/module.h>
  46 #include <linux/errno.h>
  47 #include <linux/types.h>
  48 #include <linux/socket.h>
  49 #include <linux/sockios.h>
  50 #include <linux/net.h>
  51 #include <linux/in.h>
  52 #include <linux/in6.h>
  53 #include <linux/netdevice.h>
  54 #include <linux/init.h>
  55 #include <linux/ipsec.h>
  56 #include <linux/slab.h>
  57
  58 #include <linux/ipv6.h>
  59 #include <linux/icmpv6.h>
  60 #include <linux/random.h>
  61 #include <linux/seq_file.h>
  62
  63 #include <net/protocol.h>
  64 #include <net/ndisc.h>
  65 #include <net/ip.h>
  66 #include <net/ipv6.h>
  67 #include <net/transp_v6.h>
  68 #include <net/addrconf.h>
  69 #include <net/ip6_route.h>
  70 #include <net/inet_common.h>
  71 #include <net/inet_ecn.h>
  72 #include <net/sctp/sctp.h>
  73
  74 #include <linux/uaccess.h>
  75
  76 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
  77                                          union sctp_addr *s2);
  78 static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr,
  79                               __be16 port);
  80 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
  81                             const union sctp_addr *addr2);
  82
  83 /* Event handler for inet6 address addition/deletion events.
  84  * The sctp_local_addr_list needs to be protocted by a spin lock since
  85  * multiple notifiers (say IPv4 and IPv6) may be running at the same
  86  * time and thus corrupt the list.
  87  * The reader side is protected with RCU.
  88  */
  89 static int sctp_inet6addr_event(struct notifier_block *this, unsigned long ev,
  90                                 void *ptr)
  91 {
  92         struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
  93         struct sctp_sockaddr_entry *addr = NULL;
  94         struct sctp_sockaddr_entry *temp;
  95         struct net *net = dev_net(ifa->idev->dev);
  96         int found = 0;
  97
  98         switch (ev) {
  99         case NETDEV_UP:
 100                 addr = kzalloc(sizeof(*addr), GFP_ATOMIC);
 101                 if (addr) {
 102                         addr->a.v6.sin6_family = AF_INET6;
 103                         addr->a.v6.sin6_addr = ifa->addr;
 104                         addr->a.v6.sin6_scope_id = ifa->idev->dev->ifindex;
 105                         addr->valid = 1;
 106                         spin_lock_bh(&net->sctp.local_addr_lock);
 107                         list_add_tail_rcu(&addr->list, &net->sctp.local_addr_list);
 108                         sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_NEW);
 109                         spin_unlock_bh(&net->sctp.local_addr_lock);
 110                 }
 111                 break;
 112         case NETDEV_DOWN:
 113                 spin_lock_bh(&net->sctp.local_addr_lock);
 114                 list_for_each_entry_safe(addr, temp,
 115                                         &net->sctp.local_addr_list, list) {
 116                         if (addr->a.sa.sa_family == AF_INET6 &&
 117                                         ipv6_addr_equal(&addr->a.v6.sin6_addr,
 118                                                 &ifa->addr)) {
 119                                 sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_DEL);
 120                                 found = 1;
 121                                 addr->valid = 0;
 122                                 list_del_rcu(&addr->list);
 123                                 break;
 124                         }
 125                 }
 126                 spin_unlock_bh(&net->sctp.local_addr_lock);
 127                 if (found)
 128                         kfree_rcu(addr, rcu);
 129                 break;
 130         }
 131
 132         return NOTIFY_DONE;
 133 }
 134
 135 static struct notifier_block sctp_inet6addr_notifier = {
 136         .notifier_call = sctp_inet6addr_event,
 137 };
 138
 139 /* ICMP error handler. */
 140 static void sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 141                         u8 type, u8 code, int offset, __be32 info)
 142 {
 143         struct inet6_dev *idev;
 144         struct sock *sk;
 145         struct sctp_association *asoc;
 146         struct sctp_transport *transport;
 147         struct ipv6_pinfo *np;
 148         __u16 saveip, savesctp;
 149         int err;
 150         struct net *net = dev_net(skb->dev);
 151
 152         idev = in6_dev_get(skb->dev);
 153
 154         /* Fix up skb to look at the embedded net header. */
 155         saveip   = skb->network_header;
 156         savesctp = skb->transport_header;
 157         skb_reset_network_header(skb);
 158         skb_set_transport_header(skb, offset);
 159         sk = sctp_err_lookup(net, AF_INET6, skb, sctp_hdr(skb), &asoc, &transport);
 160         /* Put back, the original pointers. */
 161         skb->network_header   = saveip;
 162         skb->transport_header = savesctp;
 163         if (!sk) {
 164                 __ICMP6_INC_STATS(net, idev, ICMP6_MIB_INERRORS);
 165                 goto out;
 166         }
 167
 168         /* Warning:  The sock lock is held.  Remember to call
 169          * sctp_err_finish!
 170          */
 171
 172         switch (type) {
 173         case ICMPV6_PKT_TOOBIG:
 174                 if (ip6_sk_accept_pmtu(sk))
 175                         sctp_icmp_frag_needed(sk, asoc, transport, ntohl(info));
 176                 goto out_unlock;
 177         case ICMPV6_PARAMPROB:
 178                 if (ICMPV6_UNK_NEXTHDR == code) {
 179                         sctp_icmp_proto_unreachable(sk, asoc, transport);
 180                         goto out_unlock;
 181                 }
 182                 break;
 183         case NDISC_REDIRECT:
 184                 sctp_icmp_redirect(sk, transport, skb);
 185                 goto out_unlock;
 186         default:
 187                 break;
 188         }
 189
 190         np = inet6_sk(sk);
 191         icmpv6_err_convert(type, code, &err);
 192         if (!sock_owned_by_user(sk) && np->recverr) {
 193                 sk->sk_err = err;
 194                 sk->sk_error_report(sk);
 195         } else {  /* Only an error on timeout */
 196                 sk->sk_err_soft = err;
 197         }
 198
 199 out_unlock:
 200         sctp_err_finish(sk, transport);
 201 out:
 202         if (likely(idev != NULL))
 203                 in6_dev_put(idev);
 204 }
 205
 206 static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *transport)
 207 {
 208         struct sock *sk = skb->sk;
 209         struct ipv6_pinfo *np = inet6_sk(sk);
 210         struct flowi6 *fl6 = &transport->fl.u.ip6;
 211         __u8 tclass = np->tclass;
 212         int res;
 213
 214         pr_debug("%s: skb:%p, len:%d, src:%pI6 dst:%pI6\n", __func__, skb,
 215                  skb->len, &fl6->saddr, &fl6->daddr);
 216
 217         if (transport->dscp & SCTP_DSCP_SET_MASK)
 218                 tclass = transport->dscp & SCTP_DSCP_VAL_MASK;
 219
 220         if (INET_ECN_is_capable(tclass))
 221                 IP6_ECN_flow_xmit(sk, fl6->flowlabel);
 222
 223         if (!(transport->param_flags & SPP_PMTUD_ENABLE))
 224                 skb->ignore_df = 1;
 225
 226         SCTP_INC_STATS(sock_net(sk), SCTP_MIB_OUTSCTPPACKS);
 227
 228         rcu_read_lock();
 229         res = ip6_xmit(sk, skb, fl6, sk->sk_mark, rcu_dereference(np->opt),
 230                        tclass);
 231         rcu_read_unlock();
 232         return res;
 233 }
 234
 235 /* Returns the dst cache entry for the given source and destination ip
 236  * addresses.
 237  */
 238 static void sctp_v6_get_dst(struct sctp_transport *t, union sctp_addr *saddr,
 239                             struct flowi *fl, struct sock *sk)
 240 {
 241         struct sctp_association *asoc = t->asoc;
 242         struct dst_entry *dst = NULL;
 243         struct flowi _fl;
 244         struct flowi6 *fl6 = &_fl.u.ip6;
 245         struct sctp_bind_addr *bp;
 246         struct ipv6_pinfo *np = inet6_sk(sk);
 247         struct sctp_sockaddr_entry *laddr;
 248         union sctp_addr *daddr = &t->ipaddr;
 249         union sctp_addr dst_saddr;
 250         struct in6_addr *final_p, final;
 251         enum sctp_scope scope;
 252         __u8 matchlen = 0;
 253
 254         memset(&_fl, 0, sizeof(_fl));
 255         fl6->daddr = daddr->v6.sin6_addr;
 256         fl6->fl6_dport = daddr->v6.sin6_port;
 257         fl6->flowi6_proto = IPPROTO_SCTP;
 258         if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
 259                 fl6->flowi6_oif = daddr->v6.sin6_scope_id;
 260         else if (asoc)
 261                 fl6->flowi6_oif = asoc->base.sk->sk_bound_dev_if;
 262         if (t->flowlabel & SCTP_FLOWLABEL_SET_MASK)
 263                 fl6->flowlabel = htonl(t->flowlabel & SCTP_FLOWLABEL_VAL_MASK);
 264
 265         if (np->sndflow && (fl6->flowlabel & IPV6_FLOWLABEL_MASK)) {
 266                 struct ip6_flowlabel *flowlabel;
 267
 268                 flowlabel = fl6_sock_lookup(sk, fl6->flowlabel);
 269                 if (!flowlabel)
 270                         goto out;
 271                 fl6_sock_release(flowlabel);
 272         }
 273
 274         pr_debug("%s: dst=%pI6 ", __func__, &fl6->daddr);
 275
 276         if (asoc)
 277                 fl6->fl6_sport = htons(asoc->base.bind_addr.port);
 278
 279         if (saddr) {
 280                 fl6->saddr = saddr->v6.sin6_addr;
 281                 if (!fl6->fl6_sport)
 282                         fl6->fl6_sport = saddr->v6.sin6_port;
 283
 284                 pr_debug("src=%pI6 - ", &fl6->saddr);
 285         }
 286
 287         rcu_read_lock();
 288         final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final);
 289         rcu_read_unlock();
 290
 291         dst = ip6_dst_lookup_flow(sock_net(sk), sk, fl6, final_p);
 292         if (!asoc || saddr) {
 293                 t->dst = dst;
 294                 memcpy(fl, &_fl, sizeof(_fl));
 295                 goto out;
 296         }
 297
 298         bp = &asoc->base.bind_addr;
 299         scope = sctp_scope(daddr);
 300         /* ip6_dst_lookup has filled in the fl6->saddr for us.  Check
 301          * to see if we can use it.
 302          */
 303         if (!IS_ERR(dst)) {
 304                 /* Walk through the bind address list and look for a bind
 305                  * address that matches the source address of the returned dst.
 306                  */
 307                 sctp_v6_to_addr(&dst_saddr, &fl6->saddr, htons(bp->port));
 308                 rcu_read_lock();
 309                 list_for_each_entry_rcu(laddr, &bp->address_list, list) {
 310                         if (!laddr->valid || laddr->state == SCTP_ADDR_DEL ||
 311                             (laddr->state != SCTP_ADDR_SRC &&
 312                              !asoc->src_out_of_asoc_ok))
 313                                 continue;
 314
 315                         /* Do not compare against v4 addrs */
 316                         if ((laddr->a.sa.sa_family == AF_INET6) &&
 317                             (sctp_v6_cmp_addr(&dst_saddr, &laddr->a))) {
 318                                 rcu_read_unlock();
 319                                 t->dst = dst;
 320                                 memcpy(fl, &_fl, sizeof(_fl));
 321                                 goto out;
 322                         }
 323                 }
 324                 rcu_read_unlock();
 325                 /* None of the bound addresses match the source address of the
 326                  * dst. So release it.
 327                  */
 328                 dst_release(dst);
 329                 dst = NULL;
 330         }
 331
 332         /* Walk through the bind address list and try to get the
 333          * best source address for a given destination.
 334          */
 335         rcu_read_lock();
 336         list_for_each_entry_rcu(laddr, &bp->address_list, list) {
 337                 struct dst_entry *bdst;
 338                 __u8 bmatchlen;
 339
 340                 if (!laddr->valid ||
 341                     laddr->state != SCTP_ADDR_SRC ||
 342                     laddr->a.sa.sa_family != AF_INET6 ||
 343                     scope > sctp_scope(&laddr->a))
 344                         continue;
 345
 346                 fl6->saddr = laddr->a.v6.sin6_addr;
 347                 fl6->fl6_sport = laddr->a.v6.sin6_port;
 348                 final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final);
 349                 bdst = ip6_dst_lookup_flow(sock_net(sk), sk, fl6, final_p);
 350
 351                 if (IS_ERR(bdst))
 352                         continue;
 353
 354                 if (ipv6_chk_addr(dev_net(bdst->dev),
 355                                   &laddr->a.v6.sin6_addr, bdst->dev, 1)) {
 356                         if (!IS_ERR_OR_NULL(dst))
 357                                 dst_release(dst);
 358                         dst = bdst;
 359                         t->dst = dst;
 360                         memcpy(fl, &_fl, sizeof(_fl));
 361                         break;
 362                 }
 363
 364                 bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
 365                 if (matchlen > bmatchlen) {
 366                         dst_release(bdst);
 367                         continue;
 368                 }
 369
 370                 if (!IS_ERR_OR_NULL(dst))
 371                         dst_release(dst);
 372                 dst = bdst;
 373                 matchlen = bmatchlen;
 374                 t->dst = dst;
 375                 memcpy(fl, &_fl, sizeof(_fl));
 376         }
 377         rcu_read_unlock();
 378
 379 out:
 380         if (!IS_ERR_OR_NULL(dst)) {
 381                 struct rt6_info *rt;
 382
 383                 rt = (struct rt6_info *)dst;
 384                 t->dst_cookie = rt6_get_cookie(rt);
 385                 pr_debug("rt6_dst:%pI6/%d rt6_src:%pI6\n",
 386                          &rt->rt6i_dst.addr, rt->rt6i_dst.plen,
 387                          &fl->u.ip6.saddr);
 388         } else {
 389                 t->dst = NULL;
 390                 pr_debug("no route\n");
 391         }
 392 }
 393
 394 /* Returns the number of consecutive initial bits that match in the 2 ipv6
 395  * addresses.
 396  */
 397 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
 398                                          union sctp_addr *s2)
 399 {
 400         return ipv6_addr_diff(&s1->v6.sin6_addr, &s2->v6.sin6_addr);
 401 }
 402
 403 /* Fills in the source address(saddr) based on the destination address(daddr)
 404  * and asoc's bind address list.
 405  */
 406 static void sctp_v6_get_saddr(struct sctp_sock *sk,
 407                               struct sctp_transport *t,
 408                               struct flowi *fl)
 409 {
 410         struct flowi6 *fl6 = &fl->u.ip6;
 411         union sctp_addr *saddr = &t->saddr;
 412
 413         pr_debug("%s: asoc:%p dst:%p\n", __func__, t->asoc, t->dst);
 414
 415         if (t->dst) {
 416                 saddr->v6.sin6_family = AF_INET6;
 417                 saddr->v6.sin6_addr = fl6->saddr;
 418         }
 419 }
 420
 421 /* Make a copy of all potential local addresses. */
 422 static void sctp_v6_copy_addrlist(struct list_head *addrlist,
 423                                   struct net_device *dev)
 424 {
 425         struct inet6_dev *in6_dev;
 426         struct inet6_ifaddr *ifp;
 427         struct sctp_sockaddr_entry *addr;
 428
 429         rcu_read_lock();
 430         if ((in6_dev = __in6_dev_get(dev)) == NULL) {
 431                 rcu_read_unlock();
 432                 return;
 433         }
 434
 435         read_lock_bh(&in6_dev->lock);
 436         list_for_each_entry(ifp, &in6_dev->addr_list, if_list) {
 437                 /* Add the address to the local list.  */
 438                 addr = kzalloc(sizeof(*addr), GFP_ATOMIC);
 439                 if (addr) {
 440                         addr->a.v6.sin6_family = AF_INET6;
 441                         addr->a.v6.sin6_addr = ifp->addr;
 442                         addr->a.v6.sin6_scope_id = dev->ifindex;
 443                         addr->valid = 1;
 444                         INIT_LIST_HEAD(&addr->list);
 445                         list_add_tail(&addr->list, addrlist);
 446                 }
 447         }
 448
 449         read_unlock_bh(&in6_dev->lock);
 450         rcu_read_unlock();
 451 }
 452
 453 /* Copy over any ip options */
 454 static void sctp_v6_copy_ip_options(struct sock *sk, struct sock *newsk)
 455 {
 456         struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
 457         struct ipv6_txoptions *opt;
 458
 459         newnp = inet6_sk(newsk);
 460
 461         rcu_read_lock();
 462         opt = rcu_dereference(np->opt);
 463         if (opt) {
 464                 opt = ipv6_dup_options(newsk, opt);
 465                 if (!opt)
 466                         pr_err("%s: Failed to copy ip options\n", __func__);
 467         }
 468         RCU_INIT_POINTER(newnp->opt, opt);
 469         rcu_read_unlock();
 470 }
 471
 472 /* Account for the IP options */
 473 static int sctp_v6_ip_options_len(struct sock *sk)
 474 {
 475         struct ipv6_pinfo *np = inet6_sk(sk);
 476         struct ipv6_txoptions *opt;
 477         int len = 0;
 478
 479         rcu_read_lock();
 480         opt = rcu_dereference(np->opt);
 481         if (opt)
 482                 len = opt->opt_flen + opt->opt_nflen;
 483
 484         rcu_read_unlock();
 485         return len;
 486 }
 487
 488 /* Initialize a sockaddr_storage from in incoming skb. */
 489 static void sctp_v6_from_skb(union sctp_addr *addr, struct sk_buff *skb,
 490                              int is_saddr)
 491 {
 492         /* Always called on head skb, so this is safe */
 493         struct sctphdr *sh = sctp_hdr(skb);
 494         struct sockaddr_in6 *sa = &addr->v6;
 495
 496         addr->v6.sin6_family = AF_INET6;
 497         addr->v6.sin6_flowinfo = 0; /* FIXME */
 498         addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif;
 499
 500         if (is_saddr) {
 501                 sa->sin6_port = sh->source;
 502                 sa->sin6_addr = ipv6_hdr(skb)->saddr;
 503         } else {
 504                 sa->sin6_port = sh->dest;
 505                 sa->sin6_addr = ipv6_hdr(skb)->daddr;
 506         }
 507 }
 508
 509 /* Initialize an sctp_addr from a socket. */
 510 static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
 511 {
 512         addr->v6.sin6_family = AF_INET6;
 513         addr->v6.sin6_port = 0;
 514         addr->v6.sin6_addr = sk->sk_v6_rcv_saddr;
 515 }
 516
 517 /* Initialize sk->sk_rcv_saddr from sctp_addr. */
 518 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
 519 {
 520         if (addr->sa.sa_family == AF_INET) {
 521                 sk->sk_v6_rcv_saddr.s6_addr32[0] = 0;
 522                 sk->sk_v6_rcv_saddr.s6_addr32[1] = 0;
 523                 sk->sk_v6_rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
 524                 sk->sk_v6_rcv_saddr.s6_addr32[3] =
 525                         addr->v4.sin_addr.s_addr;
 526         } else {
 527                 sk->sk_v6_rcv_saddr = addr->v6.sin6_addr;
 528         }
 529 }
 530
 531 /* Initialize sk->sk_daddr from sctp_addr. */
 532 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
 533 {
 534         if (addr->sa.sa_family == AF_INET) {
 535                 sk->sk_v6_daddr.s6_addr32[0] = 0;
 536                 sk->sk_v6_daddr.s6_addr32[1] = 0;
 537                 sk->sk_v6_daddr.s6_addr32[2] = htonl(0x0000ffff);
 538                 sk->sk_v6_daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
 539         } else {
 540                 sk->sk_v6_daddr = addr->v6.sin6_addr;
 541         }
 542 }
 543
 544 /* Initialize a sctp_addr from an address parameter. */
 545 static bool sctp_v6_from_addr_param(union sctp_addr *addr,
 546                                     union sctp_addr_param *param,
 547                                     __be16 port, int iif)
 548 {
 549         if (ntohs(param->v6.param_hdr.length) < sizeof(struct sctp_ipv6addr_param))
 550                 return false;
 551
 552         addr->v6.sin6_family = AF_INET6;
 553         addr->v6.sin6_port = port;
 554         addr->v6.sin6_flowinfo = 0; /* BUG */
 555         addr->v6.sin6_addr = param->v6.addr;
 556         addr->v6.sin6_scope_id = iif;
 557
 558         return true;
 559 }
 560
 561 /* Initialize an address parameter from a sctp_addr and return the length
 562  * of the address parameter.
 563  */
 564 static int sctp_v6_to_addr_param(const union sctp_addr *addr,
 565                                  union sctp_addr_param *param)
 566 {
 567         int length = sizeof(struct sctp_ipv6addr_param);
 568
 569         param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
 570         param->v6.param_hdr.length = htons(length);
 571         param->v6.addr = addr->v6.sin6_addr;
 572
 573         return length;
 574 }
 575
 576 /* Initialize a sctp_addr from struct in6_addr. */
 577 static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr,
 578                               __be16 port)
 579 {
 580         addr->sa.sa_family = AF_INET6;
 581         addr->v6.sin6_port = port;
 582         addr->v6.sin6_flowinfo = 0;
 583         addr->v6.sin6_addr = *saddr;
 584         addr->v6.sin6_scope_id = 0;
 585 }
 586
 587 static int __sctp_v6_cmp_addr(const union sctp_addr *addr1,
 588                               const union sctp_addr *addr2)
 589 {
 590         if (addr1->sa.sa_family != addr2->sa.sa_family) {
 591                 if (addr1->sa.sa_family == AF_INET &&
 592                     addr2->sa.sa_family == AF_INET6 &&
 593                     ipv6_addr_v4mapped(&addr2->v6.sin6_addr) &&
 594                     addr2->v6.sin6_addr.s6_addr32[3] ==
 595                     addr1->v4.sin_addr.s_addr)
 596                         return 1;
 597
 598                 if (addr2->sa.sa_family == AF_INET &&
 599                     addr1->sa.sa_family == AF_INET6 &&
 600                     ipv6_addr_v4mapped(&addr1->v6.sin6_addr) &&
 601                     addr1->v6.sin6_addr.s6_addr32[3] ==
 602                     addr2->v4.sin_addr.s_addr)
 603                         return 1;
 604
 605                 return 0;
 606         }
 607
 608         if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
 609                 return 0;
 610
 611         /* If this is a linklocal address, compare the scope_id. */
 612         if ((ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) &&
 613             addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
 614             addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)
 615                 return 0;
 616
 617         return 1;
 618 }
 619
 620 /* Compare addresses exactly.
 621  * v4-mapped-v6 is also in consideration.
 622  */
 623 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
 624                             const union sctp_addr *addr2)
 625 {
 626         return __sctp_v6_cmp_addr(addr1, addr2) &&
 627                addr1->v6.sin6_port == addr2->v6.sin6_port;
 628 }
 629
 630 /* Initialize addr struct to INADDR_ANY. */
 631 static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port)
 632 {
 633         memset(addr, 0x00, sizeof(union sctp_addr));
 634         addr->v6.sin6_family = AF_INET6;
 635         addr->v6.sin6_port = port;
 636 }
 637
 638 /* Is this a wildcard address? */
 639 static int sctp_v6_is_any(const union sctp_addr *addr)
 640 {
 641         return ipv6_addr_any(&addr->v6.sin6_addr);
 642 }
 643
 644 /* Should this be available for binding?   */
 645 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
 646 {
 647         int type;
 648         struct net *net = sock_net(&sp->inet.sk);
 649         const struct in6_addr *in6 = (const struct in6_addr *)&addr->v6.sin6_addr;
 650
 651         type = ipv6_addr_type(in6);
 652         if (IPV6_ADDR_ANY == type)
 653                 return 1;
 654         if (type == IPV6_ADDR_MAPPED) {
 655                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
 656                         return 0;
 657                 sctp_v6_map_v4(addr);
 658                 return sctp_get_af_specific(AF_INET)->available(addr, sp);
 659         }
 660         if (!(type & IPV6_ADDR_UNICAST))
 661                 return 0;
 662
 663         return ipv6_can_nonlocal_bind(net, &sp->inet) ||
 664                ipv6_chk_addr(net, in6, NULL, 0);
 665 }
 666
 667 /* This function checks if the address is a valid address to be used for
 668  * SCTP.
 669  *
 670  * Output:
 671  * Return 0 - If the address is a non-unicast or an illegal address.
 672  * Return 1 - If the address is a unicast.
 673  */
 674 static int sctp_v6_addr_valid(union sctp_addr *addr,
 675                               struct sctp_sock *sp,
 676                               const struct sk_buff *skb)
 677 {
 678         int ret = ipv6_addr_type(&addr->v6.sin6_addr);
 679
 680         /* Support v4-mapped-v6 address. */
 681         if (ret == IPV6_ADDR_MAPPED) {
 682                 /* Note: This routine is used in input, so v4-mapped-v6
 683                  * are disallowed here when there is no sctp_sock.
 684                  */
 685                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
 686                         return 0;
 687                 sctp_v6_map_v4(addr);
 688                 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb);
 689         }
 690
 691         /* Is this a non-unicast address */
 692         if (!(ret & IPV6_ADDR_UNICAST))
 693                 return 0;
 694
 695         return 1;
 696 }
 697
 698 /* What is the scope of 'addr'?  */
 699 static enum sctp_scope sctp_v6_scope(union sctp_addr *addr)
 700 {
 701         enum sctp_scope retval;
 702         int v6scope;
 703
 704         /* The IPv6 scope is really a set of bit fields.
 705          * See IFA_* in <net/if_inet6.h>.  Map to a generic SCTP scope.
 706          */
 707
 708         v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
 709         switch (v6scope) {
 710         case IFA_HOST:
 711                 retval = SCTP_SCOPE_LOOPBACK;
 712                 break;
 713         case IFA_LINK:
 714                 retval = SCTP_SCOPE_LINK;
 715                 break;
 716         case IFA_SITE:
 717                 retval = SCTP_SCOPE_PRIVATE;
 718                 break;
 719         default:
 720                 retval = SCTP_SCOPE_GLOBAL;
 721                 break;
 722         }
 723
 724         return retval;
 725 }
 726
 727 /* Create and initialize a new sk for the socket to be returned by accept(). */
 728 static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
 729                                              struct sctp_association *asoc,
 730                                              bool kern)
 731 {
 732         struct sock *newsk;
 733         struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
 734         struct sctp6_sock *newsctp6sk;
 735
 736         newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot, kern);
 737         if (!newsk)
 738                 goto out;
 739
 740         sock_init_data(NULL, newsk);
 741
 742         sctp_copy_sock(newsk, sk, asoc);
 743         sock_reset_flag(sk, SOCK_ZAPPED);
 744
 745         newsctp6sk = (struct sctp6_sock *)newsk;
 746         inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
 747
 748         sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped;
 749
 750         newnp = inet6_sk(newsk);
 751
 752         memcpy(newnp, np, sizeof(struct ipv6_pinfo));
 753         newnp->ipv6_mc_list = NULL;
 754         newnp->ipv6_ac_list = NULL;
 755         newnp->ipv6_fl_list = NULL;
 756
 757         sctp_v6_copy_ip_options(sk, newsk);
 758
 759         /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
 760          * and getpeername().
 761          */
 762         sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
 763
 764         newsk->sk_v6_rcv_saddr = sk->sk_v6_rcv_saddr;
 765
 766         sk_refcnt_debug_inc(newsk);
 767
 768         if (newsk->sk_prot->init(newsk)) {
 769                 sk_common_release(newsk);
 770                 newsk = NULL;
 771         }
 772
 773 out:
 774         return newsk;
 775 }
 776
 777 /* Format a sockaddr for return to user space. This makes sure the return is
 778  * AF_INET or AF_INET6 depending on the SCTP_I_WANT_MAPPED_V4_ADDR option.
 779  */
 780 static int sctp_v6_addr_to_user(struct sctp_sock *sp, union sctp_addr *addr)
 781 {
 782         if (sp->v4mapped) {
 783                 if (addr->sa.sa_family == AF_INET)
 784                         sctp_v4_map_v6(addr);
 785         } else {
 786                 if (addr->sa.sa_family == AF_INET6 &&
 787                     ipv6_addr_v4mapped(&addr->v6.sin6_addr))
 788                         sctp_v6_map_v4(addr);
 789         }
 790
 791         if (addr->sa.sa_family == AF_INET) {
 792                 memset(addr->v4.sin_zero, 0, sizeof(addr->v4.sin_zero));
 793                 return sizeof(struct sockaddr_in);
 794         }
 795         return sizeof(struct sockaddr_in6);
 796 }
 797
 798 /* Where did this skb come from?  */
 799 static int sctp_v6_skb_iif(const struct sk_buff *skb)
 800 {
 801         return IP6CB(skb)->iif;
 802 }
 803
 804 /* Was this packet marked by Explicit Congestion Notification? */
 805 static int sctp_v6_is_ce(const struct sk_buff *skb)
 806 {
 807         return *((__u32 *)(ipv6_hdr(skb))) & (__force __u32)htonl(1 << 20);
 808 }
 809
 810 /* Dump the v6 addr to the seq file. */
 811 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
 812 {
 813         seq_printf(seq, "%pI6 ", &addr->v6.sin6_addr);
 814 }
 815
 816 static void sctp_v6_ecn_capable(struct sock *sk)
 817 {
 818         inet6_sk(sk)->tclass |= INET_ECN_ECT_0;
 819 }
 820
 821 /* Initialize a PF_INET msgname from a ulpevent. */
 822 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
 823                                      char *msgname, int *addrlen)
 824 {
 825         union sctp_addr *addr;
 826         struct sctp_association *asoc;
 827         union sctp_addr *paddr;
 828
 829         if (!msgname)
 830                 return;
 831
 832         addr = (union sctp_addr *)msgname;
 833         asoc = event->asoc;
 834         paddr = &asoc->peer.primary_addr;
 835
 836         if (paddr->sa.sa_family == AF_INET) {
 837                 addr->v4.sin_family = AF_INET;
 838                 addr->v4.sin_port = htons(asoc->peer.port);
 839                 addr->v4.sin_addr = paddr->v4.sin_addr;
 840         } else {
 841                 addr->v6.sin6_family = AF_INET6;
 842                 addr->v6.sin6_flowinfo = 0;
 843                 if (ipv6_addr_type(&paddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
 844                         addr->v6.sin6_scope_id = paddr->v6.sin6_scope_id;
 845                 else
 846                         addr->v6.sin6_scope_id = 0;
 847                 addr->v6.sin6_port = htons(asoc->peer.port);
 848                 addr->v6.sin6_addr = paddr->v6.sin6_addr;
 849         }
 850
 851         *addrlen = sctp_v6_addr_to_user(sctp_sk(asoc->base.sk), addr);
 852 }
 853
 854 /* Initialize a msg_name from an inbound skb. */
 855 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
 856                                    int *addr_len)
 857 {
 858         union sctp_addr *addr;
 859         struct sctphdr *sh;
 860
 861         if (!msgname)
 862                 return;
 863
 864         addr = (union sctp_addr *)msgname;
 865         sh = sctp_hdr(skb);
 866
 867         if (ip_hdr(skb)->version == 4) {
 868                 addr->v4.sin_family = AF_INET;
 869                 addr->v4.sin_port = sh->source;
 870                 addr->v4.sin_addr.s_addr = ip_hdr(skb)->saddr;
 871         } else {
 872                 addr->v6.sin6_family = AF_INET6;
 873                 addr->v6.sin6_flowinfo = 0;
 874                 addr->v6.sin6_port = sh->source;
 875                 addr->v6.sin6_addr = ipv6_hdr(skb)->saddr;
 876                 if (ipv6_addr_type(&addr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
 877                         addr->v6.sin6_scope_id = sctp_v6_skb_iif(skb);
 878                 else
 879                         addr->v6.sin6_scope_id = 0;
 880         }
 881
 882         *addr_len = sctp_v6_addr_to_user(sctp_sk(skb->sk), addr);
 883 }
 884
 885 /* Do we support this AF? */
 886 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
 887 {
 888         switch (family) {
 889         case AF_INET6:
 890                 return 1;
 891         /* v4-mapped-v6 addresses */
 892         case AF_INET:
 893                 if (!__ipv6_only_sock(sctp_opt2sk(sp)))
 894                         return 1;
 895                 /* fallthru */
 896         default:
 897                 return 0;
 898         }
 899 }
 900
 901 /* Address matching with wildcards allowed.  This extra level
 902  * of indirection lets us choose whether a PF_INET6 should
 903  * disallow any v4 addresses if we so choose.
 904  */
 905 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
 906                                const union sctp_addr *addr2,
 907                                struct sctp_sock *opt)
 908 {
 909         struct sock *sk = sctp_opt2sk(opt);
 910         struct sctp_af *af1, *af2;
 911
 912         af1 = sctp_get_af_specific(addr1->sa.sa_family);
 913         af2 = sctp_get_af_specific(addr2->sa.sa_family);
 914
 915         if (!af1 || !af2)
 916                 return 0;
 917
 918         /* If the socket is IPv6 only, v4 addrs will not match */
 919         if (__ipv6_only_sock(sk) && af1 != af2)
 920                 return 0;
 921
 922         /* Today, wildcard AF_INET/AF_INET6. */
 923         if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2))
 924                 return 1;
 925
 926         if (addr1->sa.sa_family == AF_INET && addr2->sa.sa_family == AF_INET)
 927                 return addr1->v4.sin_addr.s_addr == addr2->v4.sin_addr.s_addr;
 928
 929         return __sctp_v6_cmp_addr(addr1, addr2);
 930 }
 931
 932 /* Verify that the provided sockaddr looks bindable.   Common verification,
 933  * has already been taken care of.
 934  */
 935 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
 936 {
 937         struct sctp_af *af;
 938
 939         /* ASSERT: address family has already been verified. */
 940         if (addr->sa.sa_family != AF_INET6)
 941                 af = sctp_get_af_specific(addr->sa.sa_family);
 942         else {
 943                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
 944                 struct net_device *dev;
 945
 946                 if (type & IPV6_ADDR_LINKLOCAL) {
 947                         struct net *net;
 948                         if (!addr->v6.sin6_scope_id)
 949                                 return 0;
 950                         net = sock_net(&opt->inet.sk);
 951                         rcu_read_lock();
 952                         dev = dev_get_by_index_rcu(net, addr->v6.sin6_scope_id);
 953                         if (!dev || !(ipv6_can_nonlocal_bind(net, &opt->inet) ||
 954                                       ipv6_chk_addr(net, &addr->v6.sin6_addr,
 955                                                     dev, 0))) {
 956                                 rcu_read_unlock();
 957                                 return 0;
 958                         }
 959                         rcu_read_unlock();
 960                 }
 961
 962                 af = opt->pf->af;
 963         }
 964         return af->available(addr, opt);
 965 }
 966
 967 /* Verify that the provided sockaddr looks sendable.   Common verification,
 968  * has already been taken care of.
 969  */
 970 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
 971 {
 972         struct sctp_af *af = NULL;
 973
 974         /* ASSERT: address family has already been verified. */
 975         if (addr->sa.sa_family != AF_INET6)
 976                 af = sctp_get_af_specific(addr->sa.sa_family);
 977         else {
 978                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
 979                 struct net_device *dev;
 980
 981                 if (type & IPV6_ADDR_LINKLOCAL) {
 982                         if (!addr->v6.sin6_scope_id)
 983                                 return 0;
 984                         rcu_read_lock();
 985                         dev = dev_get_by_index_rcu(sock_net(&opt->inet.sk),
 986                                                    addr->v6.sin6_scope_id);
 987                         rcu_read_unlock();
 988                         if (!dev)
 989                                 return 0;
 990                 }
 991                 af = opt->pf->af;
 992         }
 993
 994         return af != NULL;
 995 }
 996
 997 /* Fill in Supported Address Type information for INIT and INIT-ACK
 998  * chunks.   Note: In the future, we may want to look at sock options
 999  * to determine whether a PF_INET6 socket really wants to have IPV4
1000  * addresses.
1001  * Returns number of addresses supported.
1002  */
1003 static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
1004                                       __be16 *types)
1005 {
1006         types[0] = SCTP_PARAM_IPV6_ADDRESS;
1007         if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) {
1008                 types[1] = SCTP_PARAM_IPV4_ADDRESS;
1009                 return 2;
1010         }
1011         return 1;
1012 }
1013
1014 /* Handle SCTP_I_WANT_MAPPED_V4_ADDR for getpeername() and getsockname() */
1015 static int sctp_getname(struct socket *sock, struct sockaddr *uaddr,
1016                         int peer)
1017 {
1018         int rc;
1019
1020         rc = inet6_getname(sock, uaddr, peer);
1021
1022         if (rc < 0)
1023                 return rc;
1024
1025         rc = sctp_v6_addr_to_user(sctp_sk(sock->sk),
1026                                           (union sctp_addr *)uaddr);
1027
1028         return rc;
1029 }
1030
1031 static const struct proto_ops inet6_seqpacket_ops = {
1032         .family            = PF_INET6,
1033         .owner             = THIS_MODULE,
1034         .release           = inet6_release,
1035         .bind              = inet6_bind,
1036         .connect           = sctp_inet_connect,
1037         .socketpair        = sock_no_socketpair,
1038         .accept            = inet_accept,
1039         .getname           = sctp_getname,
1040         .poll              = sctp_poll,
1041         .ioctl             = inet6_ioctl,
1042         .listen            = sctp_inet_listen,
1043         .shutdown          = inet_shutdown,
1044         .setsockopt        = sock_common_setsockopt,
1045         .getsockopt        = sock_common_getsockopt,
1046         .sendmsg           = inet_sendmsg,
1047         .recvmsg           = inet_recvmsg,
1048         .mmap              = sock_no_mmap,
1049 #ifdef CONFIG_COMPAT
1050         .compat_setsockopt = compat_sock_common_setsockopt,
1051         .compat_getsockopt = compat_sock_common_getsockopt,
1052 #endif
1053 };
1054
1055 static struct inet_protosw sctpv6_seqpacket_protosw = {
1056         .type          = SOCK_SEQPACKET,
1057         .protocol      = IPPROTO_SCTP,
1058         .prot          = &sctpv6_prot,
1059         .ops           = &inet6_seqpacket_ops,
1060         .flags         = SCTP_PROTOSW_FLAG
1061 };
1062 static struct inet_protosw sctpv6_stream_protosw = {
1063         .type          = SOCK_STREAM,
1064         .protocol      = IPPROTO_SCTP,
1065         .prot          = &sctpv6_prot,
1066         .ops           = &inet6_seqpacket_ops,
1067         .flags         = SCTP_PROTOSW_FLAG,
1068 };
1069
1070 static int sctp6_rcv(struct sk_buff *skb)
1071 {
1072         return sctp_rcv(skb) ? -1 : 0;
1073 }
1074
1075 static const struct inet6_protocol sctpv6_protocol = {
1076         .handler      = sctp6_rcv,
1077         .err_handler  = sctp_v6_err,
1078         .flags        = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
1079 };
1080
1081 static struct sctp_af sctp_af_inet6 = {
1082         .sa_family         = AF_INET6,
1083         .sctp_xmit         = sctp_v6_xmit,
1084         .setsockopt        = ipv6_setsockopt,
1085         .getsockopt        = ipv6_getsockopt,
1086         .get_dst           = sctp_v6_get_dst,
1087         .get_saddr         = sctp_v6_get_saddr,
1088         .copy_addrlist     = sctp_v6_copy_addrlist,
1089         .from_skb          = sctp_v6_from_skb,
1090         .from_sk           = sctp_v6_from_sk,
1091         .from_addr_param   = sctp_v6_from_addr_param,
1092         .to_addr_param     = sctp_v6_to_addr_param,
1093         .cmp_addr          = sctp_v6_cmp_addr,
1094         .scope             = sctp_v6_scope,
1095         .addr_valid        = sctp_v6_addr_valid,
1096         .inaddr_any        = sctp_v6_inaddr_any,
1097         .is_any            = sctp_v6_is_any,
1098         .available         = sctp_v6_available,
1099         .skb_iif           = sctp_v6_skb_iif,
1100         .is_ce             = sctp_v6_is_ce,
1101         .seq_dump_addr     = sctp_v6_seq_dump_addr,
1102         .ecn_capable       = sctp_v6_ecn_capable,
1103         .net_header_len    = sizeof(struct ipv6hdr),
1104         .sockaddr_len      = sizeof(struct sockaddr_in6),
1105         .ip_options_len    = sctp_v6_ip_options_len,
1106 #ifdef CONFIG_COMPAT
1107         .compat_setsockopt = compat_ipv6_setsockopt,
1108         .compat_getsockopt = compat_ipv6_getsockopt,
1109 #endif
1110 };
1111
1112 static struct sctp_pf sctp_pf_inet6 = {
1113         .event_msgname = sctp_inet6_event_msgname,
1114         .skb_msgname   = sctp_inet6_skb_msgname,
1115         .af_supported  = sctp_inet6_af_supported,
1116         .cmp_addr      = sctp_inet6_cmp_addr,
1117         .bind_verify   = sctp_inet6_bind_verify,
1118         .send_verify   = sctp_inet6_send_verify,
1119         .supported_addrs = sctp_inet6_supported_addrs,
1120         .create_accept_sk = sctp_v6_create_accept_sk,
1121         .addr_to_user  = sctp_v6_addr_to_user,
1122         .to_sk_saddr   = sctp_v6_to_sk_saddr,
1123         .to_sk_daddr   = sctp_v6_to_sk_daddr,
1124         .copy_ip_options = sctp_v6_copy_ip_options,
1125         .af            = &sctp_af_inet6,
1126 };
1127
1128 /* Initialize IPv6 support and register with socket layer.  */
1129 void sctp_v6_pf_init(void)
1130 {
1131         /* Register the SCTP specific PF_INET6 functions. */
1132         sctp_register_pf(&sctp_pf_inet6, PF_INET6);
1133
1134         /* Register the SCTP specific AF_INET6 functions. */
1135         sctp_register_af(&sctp_af_inet6);
1136 }
1137
1138 void sctp_v6_pf_exit(void)
1139 {
1140         list_del(&sctp_af_inet6.list);
1141 }
1142
1143 /* Initialize IPv6 support and register with socket layer.  */
1144 int sctp_v6_protosw_init(void)
1145 {
1146         int rc;
1147
1148         rc = proto_register(&sctpv6_prot, 1);
1149         if (rc)
1150                 return rc;
1151
1152         /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
1153         inet6_register_protosw(&sctpv6_seqpacket_protosw);
1154         inet6_register_protosw(&sctpv6_stream_protosw);
1155
1156         return 0;
1157 }
1158
1159 void sctp_v6_protosw_exit(void)
1160 {
1161         inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
1162         inet6_unregister_protosw(&sctpv6_stream_protosw);
1163         proto_unregister(&sctpv6_prot);
1164 }
1165
1166
1167 /* Register with inet6 layer. */
1168 int sctp_v6_add_protocol(void)
1169 {
1170         /* Register notifier for inet6 address additions/deletions. */
1171         register_inet6addr_notifier(&sctp_inet6addr_notifier);
1172
1173         if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
1174                 return -EAGAIN;
1175
1176         return 0;
1177 }
1178
1179 /* Unregister with inet6 layer. */
1180 void sctp_v6_del_protocol(void)
1181 {
1182         inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
1183         unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1184 }