net/sctp/ipv6.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /* SCTP kernel implementation
   3  * (C) Copyright IBM Corp. 2002, 2004
   4  * Copyright (c) 2001 Nokia, Inc.
   5  * Copyright (c) 2001 La Monte H.P. Yarroll
   6  * Copyright (c) 2002-2003 Intel Corp.
   7  *
   8  * This file is part of the SCTP kernel implementation
   9  *
  10  * SCTP over IPv6.
  11  *
  12  * Please send any bug reports or fixes you make to the
  13  * email address(es):
  14  *    lksctp developers <linux-sctp@vger.kernel.org>
  15  *
  16  * Written or modified by:
  17  *    Le Yanqun             <yanqun.le@nokia.com>
  18  *    Hui Huang             <hui.huang@nokia.com>
  19  *    La Monte H.P. Yarroll <piggy@acm.org>
  20  *    Sridhar Samudrala     <sri@us.ibm.com>
  21  *    Jon Grimm             <jgrimm@us.ibm.com>
  22  *    Ardelle Fan           <ardelle.fan@intel.com>
  23  *
  24  * Based on:
  25  *      linux/net/ipv6/tcp_ipv6.c
  26  */
  27
  28 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  29
  30 #include <linux/module.h>
  31 #include <linux/errno.h>
  32 #include <linux/types.h>
  33 #include <linux/socket.h>
  34 #include <linux/sockios.h>
  35 #include <linux/net.h>
  36 #include <linux/in.h>
  37 #include <linux/in6.h>
  38 #include <linux/netdevice.h>
  39 #include <linux/init.h>
  40 #include <linux/ipsec.h>
  41 #include <linux/slab.h>
  42
  43 #include <linux/ipv6.h>
  44 #include <linux/icmpv6.h>
  45 #include <linux/random.h>
  46 #include <linux/seq_file.h>
  47
  48 #include <net/protocol.h>
  49 #include <net/ndisc.h>
  50 #include <net/ip.h>
  51 #include <net/ipv6.h>
  52 #include <net/transp_v6.h>
  53 #include <net/addrconf.h>
  54 #include <net/ip6_route.h>
  55 #include <net/inet_common.h>
  56 #include <net/inet_ecn.h>
  57 #include <net/sctp/sctp.h>
  58 #include <net/udp_tunnel.h>
  59
  60 #include <linux/uaccess.h>
  61
  62 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
  63                                          union sctp_addr *s2);
  64 static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr,
  65                               __be16 port);
  66 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
  67                             const union sctp_addr *addr2);
  68
  69 /* Event handler for inet6 address addition/deletion events.
  70  * The sctp_local_addr_list needs to be protocted by a spin lock since
  71  * multiple notifiers (say IPv4 and IPv6) may be running at the same
  72  * time and thus corrupt the list.
  73  * The reader side is protected with RCU.
  74  */
  75 static int sctp_inet6addr_event(struct notifier_block *this, unsigned long ev,
  76                                 void *ptr)
  77 {
  78         struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
  79         struct sctp_sockaddr_entry *addr = NULL;
  80         struct sctp_sockaddr_entry *temp;
  81         struct net *net = dev_net(ifa->idev->dev);
  82         int found = 0;
  83
  84         switch (ev) {
  85         case NETDEV_UP:
  86                 addr = kzalloc(sizeof(*addr), GFP_ATOMIC);
  87                 if (addr) {
  88                         addr->a.v6.sin6_family = AF_INET6;
  89                         addr->a.v6.sin6_addr = ifa->addr;
  90                         addr->a.v6.sin6_scope_id = ifa->idev->dev->ifindex;
  91                         addr->valid = 1;
  92                         spin_lock_bh(&net->sctp.local_addr_lock);
  93                         list_add_tail_rcu(&addr->list, &net->sctp.local_addr_list);
  94                         sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_NEW);
  95                         spin_unlock_bh(&net->sctp.local_addr_lock);
  96                 }
  97                 break;
  98         case NETDEV_DOWN:
  99                 spin_lock_bh(&net->sctp.local_addr_lock);
 100                 list_for_each_entry_safe(addr, temp,
 101                                         &net->sctp.local_addr_list, list) {
 102                         if (addr->a.sa.sa_family == AF_INET6 &&
 103                             ipv6_addr_equal(&addr->a.v6.sin6_addr,
 104                                             &ifa->addr) &&
 105                             addr->a.v6.sin6_scope_id == ifa->idev->dev->ifindex) {
 106                                 sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_DEL);
 107                                 found = 1;
 108                                 addr->valid = 0;
 109                                 list_del_rcu(&addr->list);
 110                                 break;
 111                         }
 112                 }
 113                 spin_unlock_bh(&net->sctp.local_addr_lock);
 114                 if (found)
 115                         kfree_rcu(addr, rcu);
 116                 break;
 117         }
 118
 119         return NOTIFY_DONE;
 120 }
 121
 122 static struct notifier_block sctp_inet6addr_notifier = {
 123         .notifier_call = sctp_inet6addr_event,
 124 };
 125
 126 static void sctp_v6_err_handle(struct sctp_transport *t, struct sk_buff *skb,
 127                                __u8 type, __u8 code, __u32 info)
 128 {
 129         struct sctp_association *asoc = t->asoc;
 130         struct sock *sk = asoc->base.sk;
 131         struct ipv6_pinfo *np;
 132         int err = 0;
 133
 134         switch (type) {
 135         case ICMPV6_PKT_TOOBIG:
 136                 if (ip6_sk_accept_pmtu(sk))
 137                         sctp_icmp_frag_needed(sk, asoc, t, info);
 138                 return;
 139         case ICMPV6_PARAMPROB:
 140                 if (ICMPV6_UNK_NEXTHDR == code) {
 141                         sctp_icmp_proto_unreachable(sk, asoc, t);
 142                         return;
 143                 }
 144                 break;
 145         case NDISC_REDIRECT:
 146                 sctp_icmp_redirect(sk, t, skb);
 147                 return;
 148         default:
 149                 break;
 150         }
 151
 152         np = inet6_sk(sk);
 153         icmpv6_err_convert(type, code, &err);
 154         if (!sock_owned_by_user(sk) && np->recverr) {
 155                 sk->sk_err = err;
 156                 sk_error_report(sk);
 157         } else {
 158                 WRITE_ONCE(sk->sk_err_soft, err);
 159         }
 160 }
 161
 162 /* ICMP error handler. */
 163 static int sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 164                        u8 type, u8 code, int offset, __be32 info)
 165 {
 166         struct net *net = dev_net(skb->dev);
 167         struct sctp_transport *transport;
 168         struct sctp_association *asoc;
 169         __u16 saveip, savesctp;
 170         struct sock *sk;
 171
 172         /* Fix up skb to look at the embedded net header. */
 173         saveip   = skb->network_header;
 174         savesctp = skb->transport_header;
 175         skb_reset_network_header(skb);
 176         skb_set_transport_header(skb, offset);
 177         sk = sctp_err_lookup(net, AF_INET6, skb, sctp_hdr(skb), &asoc, &transport);
 178         /* Put back, the original pointers. */
 179         skb->network_header   = saveip;
 180         skb->transport_header = savesctp;
 181         if (!sk) {
 182                 __ICMP6_INC_STATS(net, __in6_dev_get(skb->dev), ICMP6_MIB_INERRORS);
 183                 return -ENOENT;
 184         }
 185
 186         sctp_v6_err_handle(transport, skb, type, code, ntohl(info));
 187         sctp_err_finish(sk, transport);
 188
 189         return 0;
 190 }
 191
 192 int sctp_udp_v6_err(struct sock *sk, struct sk_buff *skb)
 193 {
 194         struct net *net = dev_net(skb->dev);
 195         struct sctp_association *asoc;
 196         struct sctp_transport *t;
 197         struct icmp6hdr *hdr;
 198         __u32 info = 0;
 199
 200         skb->transport_header += sizeof(struct udphdr);
 201         sk = sctp_err_lookup(net, AF_INET6, skb, sctp_hdr(skb), &asoc, &t);
 202         if (!sk) {
 203                 __ICMP6_INC_STATS(net, __in6_dev_get(skb->dev), ICMP6_MIB_INERRORS);
 204                 return -ENOENT;
 205         }
 206
 207         skb->transport_header -= sizeof(struct udphdr);
 208         hdr = (struct icmp6hdr *)(skb_network_header(skb) - sizeof(struct icmp6hdr));
 209         if (hdr->icmp6_type == NDISC_REDIRECT) {
 210                 /* can't be handled without outer ip6hdr known, leave it to udpv6_err */
 211                 sctp_err_finish(sk, t);
 212                 return 0;
 213         }
 214         if (hdr->icmp6_type == ICMPV6_PKT_TOOBIG)
 215                 info = ntohl(hdr->icmp6_mtu);
 216         sctp_v6_err_handle(t, skb, hdr->icmp6_type, hdr->icmp6_code, info);
 217
 218         sctp_err_finish(sk, t);
 219         return 1;
 220 }
 221
 222 static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *t)
 223 {
 224         struct dst_entry *dst = dst_clone(t->dst);
 225         struct flowi6 *fl6 = &t->fl.u.ip6;
 226         struct sock *sk = skb->sk;
 227         struct ipv6_pinfo *np = inet6_sk(sk);
 228         __u8 tclass = np->tclass;
 229         __be32 label;
 230
 231         pr_debug("%s: skb:%p, len:%d, src:%pI6 dst:%pI6\n", __func__, skb,
 232                  skb->len, &fl6->saddr, &fl6->daddr);
 233
 234         if (t->dscp & SCTP_DSCP_SET_MASK)
 235                 tclass = t->dscp & SCTP_DSCP_VAL_MASK;
 236
 237         if (INET_ECN_is_capable(tclass))
 238                 IP6_ECN_flow_xmit(sk, fl6->flowlabel);
 239
 240         if (!(t->param_flags & SPP_PMTUD_ENABLE))
 241                 skb->ignore_df = 1;
 242
 243         SCTP_INC_STATS(sock_net(sk), SCTP_MIB_OUTSCTPPACKS);
 244
 245         if (!t->encap_port || !sctp_sk(sk)->udp_port) {
 246                 int res;
 247
 248                 skb_dst_set(skb, dst);
 249                 rcu_read_lock();
 250                 res = ip6_xmit(sk, skb, fl6, sk->sk_mark,
 251                                rcu_dereference(np->opt),
 252                                tclass, sk->sk_priority);
 253                 rcu_read_unlock();
 254                 return res;
 255         }
 256
 257         if (skb_is_gso(skb))
 258                 skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_TUNNEL_CSUM;
 259
 260         skb->encapsulation = 1;
 261         skb_reset_inner_mac_header(skb);
 262         skb_reset_inner_transport_header(skb);
 263         skb_set_inner_ipproto(skb, IPPROTO_SCTP);
 264         label = ip6_make_flowlabel(sock_net(sk), skb, fl6->flowlabel, true, fl6);
 265
 266         return udp_tunnel6_xmit_skb(dst, sk, skb, NULL, &fl6->saddr,
 267                                     &fl6->daddr, tclass, ip6_dst_hoplimit(dst),
 268                                     label, sctp_sk(sk)->udp_port, t->encap_port, false);
 269 }
 270
 271 /* Returns the dst cache entry for the given source and destination ip
 272  * addresses.
 273  */
 274 static void sctp_v6_get_dst(struct sctp_transport *t, union sctp_addr *saddr,
 275                             struct flowi *fl, struct sock *sk)
 276 {
 277         struct sctp_association *asoc = t->asoc;
 278         struct dst_entry *dst = NULL;
 279         struct flowi _fl;
 280         struct flowi6 *fl6 = &_fl.u.ip6;
 281         struct sctp_bind_addr *bp;
 282         struct ipv6_pinfo *np = inet6_sk(sk);
 283         struct sctp_sockaddr_entry *laddr;
 284         union sctp_addr *daddr = &t->ipaddr;
 285         union sctp_addr dst_saddr;
 286         struct in6_addr *final_p, final;
 287         enum sctp_scope scope;
 288         __u8 matchlen = 0;
 289
 290         memset(&_fl, 0, sizeof(_fl));
 291         fl6->daddr = daddr->v6.sin6_addr;
 292         fl6->fl6_dport = daddr->v6.sin6_port;
 293         fl6->flowi6_proto = IPPROTO_SCTP;
 294         if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
 295                 fl6->flowi6_oif = daddr->v6.sin6_scope_id;
 296         else if (asoc)
 297                 fl6->flowi6_oif = asoc->base.sk->sk_bound_dev_if;
 298         if (t->flowlabel & SCTP_FLOWLABEL_SET_MASK)
 299                 fl6->flowlabel = htonl(t->flowlabel & SCTP_FLOWLABEL_VAL_MASK);
 300
 301         if (np->sndflow && (fl6->flowlabel & IPV6_FLOWLABEL_MASK)) {
 302                 struct ip6_flowlabel *flowlabel;
 303
 304                 flowlabel = fl6_sock_lookup(sk, fl6->flowlabel);
 305                 if (IS_ERR(flowlabel))
 306                         goto out;
 307                 fl6_sock_release(flowlabel);
 308         }
 309
 310         pr_debug("%s: dst=%pI6 ", __func__, &fl6->daddr);
 311
 312         if (asoc)
 313                 fl6->fl6_sport = htons(asoc->base.bind_addr.port);
 314
 315         if (saddr) {
 316                 fl6->saddr = saddr->v6.sin6_addr;
 317                 if (!fl6->fl6_sport)
 318                         fl6->fl6_sport = saddr->v6.sin6_port;
 319
 320                 pr_debug("src=%pI6 - ", &fl6->saddr);
 321         }
 322
 323         rcu_read_lock();
 324         final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final);
 325         rcu_read_unlock();
 326
 327         dst = ip6_dst_lookup_flow(sock_net(sk), sk, fl6, final_p);
 328         if (!asoc || saddr) {
 329                 t->dst = dst;
 330                 memcpy(fl, &_fl, sizeof(_fl));
 331                 goto out;
 332         }
 333
 334         bp = &asoc->base.bind_addr;
 335         scope = sctp_scope(daddr);
 336         /* ip6_dst_lookup has filled in the fl6->saddr for us.  Check
 337          * to see if we can use it.
 338          */
 339         if (!IS_ERR(dst)) {
 340                 /* Walk through the bind address list and look for a bind
 341                  * address that matches the source address of the returned dst.
 342                  */
 343                 sctp_v6_to_addr(&dst_saddr, &fl6->saddr, htons(bp->port));
 344                 rcu_read_lock();
 345                 list_for_each_entry_rcu(laddr, &bp->address_list, list) {
 346                         if (!laddr->valid || laddr->state == SCTP_ADDR_DEL ||
 347                             (laddr->state != SCTP_ADDR_SRC &&
 348                              !asoc->src_out_of_asoc_ok))
 349                                 continue;
 350
 351                         /* Do not compare against v4 addrs */
 352                         if ((laddr->a.sa.sa_family == AF_INET6) &&
 353                             (sctp_v6_cmp_addr(&dst_saddr, &laddr->a))) {
 354                                 rcu_read_unlock();
 355                                 t->dst = dst;
 356                                 memcpy(fl, &_fl, sizeof(_fl));
 357                                 goto out;
 358                         }
 359                 }
 360                 rcu_read_unlock();
 361                 /* None of the bound addresses match the source address of the
 362                  * dst. So release it.
 363                  */
 364                 dst_release(dst);
 365                 dst = NULL;
 366         }
 367
 368         /* Walk through the bind address list and try to get the
 369          * best source address for a given destination.
 370          */
 371         rcu_read_lock();
 372         list_for_each_entry_rcu(laddr, &bp->address_list, list) {
 373                 struct dst_entry *bdst;
 374                 __u8 bmatchlen;
 375
 376                 if (!laddr->valid ||
 377                     laddr->state != SCTP_ADDR_SRC ||
 378                     laddr->a.sa.sa_family != AF_INET6 ||
 379                     scope > sctp_scope(&laddr->a))
 380                         continue;
 381
 382                 fl6->saddr = laddr->a.v6.sin6_addr;
 383                 fl6->fl6_sport = laddr->a.v6.sin6_port;
 384                 final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final);
 385                 bdst = ip6_dst_lookup_flow(sock_net(sk), sk, fl6, final_p);
 386
 387                 if (IS_ERR(bdst))
 388                         continue;
 389
 390                 if (ipv6_chk_addr(dev_net(bdst->dev),
 391                                   &laddr->a.v6.sin6_addr, bdst->dev, 1)) {
 392                         if (!IS_ERR_OR_NULL(dst))
 393                                 dst_release(dst);
 394                         dst = bdst;
 395                         t->dst = dst;
 396                         memcpy(fl, &_fl, sizeof(_fl));
 397                         break;
 398                 }
 399
 400                 bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
 401                 if (matchlen > bmatchlen) {
 402                         dst_release(bdst);
 403                         continue;
 404                 }
 405
 406                 if (!IS_ERR_OR_NULL(dst))
 407                         dst_release(dst);
 408                 dst = bdst;
 409                 matchlen = bmatchlen;
 410                 t->dst = dst;
 411                 memcpy(fl, &_fl, sizeof(_fl));
 412         }
 413         rcu_read_unlock();
 414
 415 out:
 416         if (!IS_ERR_OR_NULL(dst)) {
 417                 struct rt6_info *rt;
 418
 419                 rt = (struct rt6_info *)dst;
 420                 t->dst_cookie = rt6_get_cookie(rt);
 421                 pr_debug("rt6_dst:%pI6/%d rt6_src:%pI6\n",
 422                          &rt->rt6i_dst.addr, rt->rt6i_dst.plen,
 423                          &fl->u.ip6.saddr);
 424         } else {
 425                 t->dst = NULL;
 426                 pr_debug("no route\n");
 427         }
 428 }
 429
 430 /* Returns the number of consecutive initial bits that match in the 2 ipv6
 431  * addresses.
 432  */
 433 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
 434                                          union sctp_addr *s2)
 435 {
 436         return ipv6_addr_diff(&s1->v6.sin6_addr, &s2->v6.sin6_addr);
 437 }
 438
 439 /* Fills in the source address(saddr) based on the destination address(daddr)
 440  * and asoc's bind address list.
 441  */
 442 static void sctp_v6_get_saddr(struct sctp_sock *sk,
 443                               struct sctp_transport *t,
 444                               struct flowi *fl)
 445 {
 446         struct flowi6 *fl6 = &fl->u.ip6;
 447         union sctp_addr *saddr = &t->saddr;
 448
 449         pr_debug("%s: asoc:%p dst:%p\n", __func__, t->asoc, t->dst);
 450
 451         if (t->dst) {
 452                 saddr->v6.sin6_family = AF_INET6;
 453                 saddr->v6.sin6_addr = fl6->saddr;
 454         }
 455 }
 456
 457 /* Make a copy of all potential local addresses. */
 458 static void sctp_v6_copy_addrlist(struct list_head *addrlist,
 459                                   struct net_device *dev)
 460 {
 461         struct inet6_dev *in6_dev;
 462         struct inet6_ifaddr *ifp;
 463         struct sctp_sockaddr_entry *addr;
 464
 465         rcu_read_lock();
 466         if ((in6_dev = __in6_dev_get(dev)) == NULL) {
 467                 rcu_read_unlock();
 468                 return;
 469         }
 470
 471         read_lock_bh(&in6_dev->lock);
 472         list_for_each_entry(ifp, &in6_dev->addr_list, if_list) {
 473                 /* Add the address to the local list.  */
 474                 addr = kzalloc(sizeof(*addr), GFP_ATOMIC);
 475                 if (addr) {
 476                         addr->a.v6.sin6_family = AF_INET6;
 477                         addr->a.v6.sin6_addr = ifp->addr;
 478                         addr->a.v6.sin6_scope_id = dev->ifindex;
 479                         addr->valid = 1;
 480                         INIT_LIST_HEAD(&addr->list);
 481                         list_add_tail(&addr->list, addrlist);
 482                 }
 483         }
 484
 485         read_unlock_bh(&in6_dev->lock);
 486         rcu_read_unlock();
 487 }
 488
 489 /* Copy over any ip options */
 490 static void sctp_v6_copy_ip_options(struct sock *sk, struct sock *newsk)
 491 {
 492         struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
 493         struct ipv6_txoptions *opt;
 494
 495         newnp = inet6_sk(newsk);
 496
 497         rcu_read_lock();
 498         opt = rcu_dereference(np->opt);
 499         if (opt) {
 500                 opt = ipv6_dup_options(newsk, opt);
 501                 if (!opt)
 502                         pr_err("%s: Failed to copy ip options\n", __func__);
 503         }
 504         RCU_INIT_POINTER(newnp->opt, opt);
 505         rcu_read_unlock();
 506 }
 507
 508 /* Account for the IP options */
 509 static int sctp_v6_ip_options_len(struct sock *sk)
 510 {
 511         struct ipv6_pinfo *np = inet6_sk(sk);
 512         struct ipv6_txoptions *opt;
 513         int len = 0;
 514
 515         rcu_read_lock();
 516         opt = rcu_dereference(np->opt);
 517         if (opt)
 518                 len = opt->opt_flen + opt->opt_nflen;
 519
 520         rcu_read_unlock();
 521         return len;
 522 }
 523
 524 /* Initialize a sockaddr_storage from in incoming skb. */
 525 static void sctp_v6_from_skb(union sctp_addr *addr, struct sk_buff *skb,
 526                              int is_saddr)
 527 {
 528         /* Always called on head skb, so this is safe */
 529         struct sctphdr *sh = sctp_hdr(skb);
 530         struct sockaddr_in6 *sa = &addr->v6;
 531
 532         addr->v6.sin6_family = AF_INET6;
 533         addr->v6.sin6_flowinfo = 0; /* FIXME */
 534         addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif;
 535
 536         if (is_saddr) {
 537                 sa->sin6_port = sh->source;
 538                 sa->sin6_addr = ipv6_hdr(skb)->saddr;
 539         } else {
 540                 sa->sin6_port = sh->dest;
 541                 sa->sin6_addr = ipv6_hdr(skb)->daddr;
 542         }
 543 }
 544
 545 /* Initialize an sctp_addr from a socket. */
 546 static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
 547 {
 548         addr->v6.sin6_family = AF_INET6;
 549         addr->v6.sin6_port = 0;
 550         addr->v6.sin6_addr = sk->sk_v6_rcv_saddr;
 551 }
 552
 553 /* Initialize sk->sk_rcv_saddr from sctp_addr. */
 554 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
 555 {
 556         if (addr->sa.sa_family == AF_INET) {
 557                 sk->sk_v6_rcv_saddr.s6_addr32[0] = 0;
 558                 sk->sk_v6_rcv_saddr.s6_addr32[1] = 0;
 559                 sk->sk_v6_rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
 560                 sk->sk_v6_rcv_saddr.s6_addr32[3] =
 561                         addr->v4.sin_addr.s_addr;
 562         } else {
 563                 sk->sk_v6_rcv_saddr = addr->v6.sin6_addr;
 564         }
 565 }
 566
 567 /* Initialize sk->sk_daddr from sctp_addr. */
 568 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
 569 {
 570         if (addr->sa.sa_family == AF_INET) {
 571                 sk->sk_v6_daddr.s6_addr32[0] = 0;
 572                 sk->sk_v6_daddr.s6_addr32[1] = 0;
 573                 sk->sk_v6_daddr.s6_addr32[2] = htonl(0x0000ffff);
 574                 sk->sk_v6_daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
 575         } else {
 576                 sk->sk_v6_daddr = addr->v6.sin6_addr;
 577         }
 578 }
 579
 580 /* Initialize a sctp_addr from an address parameter. */
 581 static bool sctp_v6_from_addr_param(union sctp_addr *addr,
 582                                     union sctp_addr_param *param,
 583                                     __be16 port, int iif)
 584 {
 585         if (ntohs(param->v6.param_hdr.length) < sizeof(struct sctp_ipv6addr_param))
 586                 return false;
 587
 588         addr->v6.sin6_family = AF_INET6;
 589         addr->v6.sin6_port = port;
 590         addr->v6.sin6_flowinfo = 0; /* BUG */
 591         addr->v6.sin6_addr = param->v6.addr;
 592         addr->v6.sin6_scope_id = iif;
 593
 594         return true;
 595 }
 596
 597 /* Initialize an address parameter from a sctp_addr and return the length
 598  * of the address parameter.
 599  */
 600 static int sctp_v6_to_addr_param(const union sctp_addr *addr,
 601                                  union sctp_addr_param *param)
 602 {
 603         int length = sizeof(struct sctp_ipv6addr_param);
 604
 605         param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
 606         param->v6.param_hdr.length = htons(length);
 607         param->v6.addr = addr->v6.sin6_addr;
 608
 609         return length;
 610 }
 611
 612 /* Initialize a sctp_addr from struct in6_addr. */
 613 static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr,
 614                               __be16 port)
 615 {
 616         addr->sa.sa_family = AF_INET6;
 617         addr->v6.sin6_port = port;
 618         addr->v6.sin6_flowinfo = 0;
 619         addr->v6.sin6_addr = *saddr;
 620         addr->v6.sin6_scope_id = 0;
 621 }
 622
 623 static int __sctp_v6_cmp_addr(const union sctp_addr *addr1,
 624                               const union sctp_addr *addr2)
 625 {
 626         if (addr1->sa.sa_family != addr2->sa.sa_family) {
 627                 if (addr1->sa.sa_family == AF_INET &&
 628                     addr2->sa.sa_family == AF_INET6 &&
 629                     ipv6_addr_v4mapped(&addr2->v6.sin6_addr) &&
 630                     addr2->v6.sin6_addr.s6_addr32[3] ==
 631                     addr1->v4.sin_addr.s_addr)
 632                         return 1;
 633
 634                 if (addr2->sa.sa_family == AF_INET &&
 635                     addr1->sa.sa_family == AF_INET6 &&
 636                     ipv6_addr_v4mapped(&addr1->v6.sin6_addr) &&
 637                     addr1->v6.sin6_addr.s6_addr32[3] ==
 638                     addr2->v4.sin_addr.s_addr)
 639                         return 1;
 640
 641                 return 0;
 642         }
 643
 644         if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
 645                 return 0;
 646
 647         /* If this is a linklocal address, compare the scope_id. */
 648         if ((ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) &&
 649             addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
 650             addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)
 651                 return 0;
 652
 653         return 1;
 654 }
 655
 656 /* Compare addresses exactly.
 657  * v4-mapped-v6 is also in consideration.
 658  */
 659 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
 660                             const union sctp_addr *addr2)
 661 {
 662         return __sctp_v6_cmp_addr(addr1, addr2) &&
 663                addr1->v6.sin6_port == addr2->v6.sin6_port;
 664 }
 665
 666 /* Initialize addr struct to INADDR_ANY. */
 667 static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port)
 668 {
 669         memset(addr, 0x00, sizeof(union sctp_addr));
 670         addr->v6.sin6_family = AF_INET6;
 671         addr->v6.sin6_port = port;
 672 }
 673
 674 /* Is this a wildcard address? */
 675 static int sctp_v6_is_any(const union sctp_addr *addr)
 676 {
 677         return ipv6_addr_any(&addr->v6.sin6_addr);
 678 }
 679
 680 /* Should this be available for binding?   */
 681 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
 682 {
 683         const struct in6_addr *in6 = (const struct in6_addr *)&addr->v6.sin6_addr;
 684         struct sock *sk = &sp->inet.sk;
 685         struct net *net = sock_net(sk);
 686         struct net_device *dev = NULL;
 687         int type;
 688
 689         type = ipv6_addr_type(in6);
 690         if (IPV6_ADDR_ANY == type)
 691                 return 1;
 692         if (type == IPV6_ADDR_MAPPED) {
 693                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
 694                         return 0;
 695                 sctp_v6_map_v4(addr);
 696                 return sctp_get_af_specific(AF_INET)->available(addr, sp);
 697         }
 698         if (!(type & IPV6_ADDR_UNICAST))
 699                 return 0;
 700
 701         if (sk->sk_bound_dev_if) {
 702                 dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if);
 703                 if (!dev)
 704                         return 0;
 705         }
 706
 707         return ipv6_can_nonlocal_bind(net, &sp->inet) ||
 708                ipv6_chk_addr(net, in6, dev, 0);
 709 }
 710
 711 /* This function checks if the address is a valid address to be used for
 712  * SCTP.
 713  *
 714  * Output:
 715  * Return 0 - If the address is a non-unicast or an illegal address.
 716  * Return 1 - If the address is a unicast.
 717  */
 718 static int sctp_v6_addr_valid(union sctp_addr *addr,
 719                               struct sctp_sock *sp,
 720                               const struct sk_buff *skb)
 721 {
 722         int ret = ipv6_addr_type(&addr->v6.sin6_addr);
 723
 724         /* Support v4-mapped-v6 address. */
 725         if (ret == IPV6_ADDR_MAPPED) {
 726                 /* Note: This routine is used in input, so v4-mapped-v6
 727                  * are disallowed here when there is no sctp_sock.
 728                  */
 729                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
 730                         return 0;
 731                 sctp_v6_map_v4(addr);
 732                 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb);
 733         }
 734
 735         /* Is this a non-unicast address */
 736         if (!(ret & IPV6_ADDR_UNICAST))
 737                 return 0;
 738
 739         return 1;
 740 }
 741
 742 /* What is the scope of 'addr'?  */
 743 static enum sctp_scope sctp_v6_scope(union sctp_addr *addr)
 744 {
 745         enum sctp_scope retval;
 746         int v6scope;
 747
 748         /* The IPv6 scope is really a set of bit fields.
 749          * See IFA_* in <net/if_inet6.h>.  Map to a generic SCTP scope.
 750          */
 751
 752         v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
 753         switch (v6scope) {
 754         case IFA_HOST:
 755                 retval = SCTP_SCOPE_LOOPBACK;
 756                 break;
 757         case IFA_LINK:
 758                 retval = SCTP_SCOPE_LINK;
 759                 break;
 760         case IFA_SITE:
 761                 retval = SCTP_SCOPE_PRIVATE;
 762                 break;
 763         default:
 764                 retval = SCTP_SCOPE_GLOBAL;
 765                 break;
 766         }
 767
 768         return retval;
 769 }
 770
 771 /* Create and initialize a new sk for the socket to be returned by accept(). */
 772 static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
 773                                              struct sctp_association *asoc,
 774                                              bool kern)
 775 {
 776         struct sock *newsk;
 777         struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
 778         struct sctp6_sock *newsctp6sk;
 779
 780         newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot, kern);
 781         if (!newsk)
 782                 goto out;
 783
 784         sock_init_data(NULL, newsk);
 785
 786         sctp_copy_sock(newsk, sk, asoc);
 787         sock_reset_flag(sk, SOCK_ZAPPED);
 788
 789         newsctp6sk = (struct sctp6_sock *)newsk;
 790         inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
 791
 792         sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped;
 793
 794         newnp = inet6_sk(newsk);
 795
 796         memcpy(newnp, np, sizeof(struct ipv6_pinfo));
 797         newnp->ipv6_mc_list = NULL;
 798         newnp->ipv6_ac_list = NULL;
 799         newnp->ipv6_fl_list = NULL;
 800
 801         sctp_v6_copy_ip_options(sk, newsk);
 802
 803         /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
 804          * and getpeername().
 805          */
 806         sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
 807
 808         newsk->sk_v6_rcv_saddr = sk->sk_v6_rcv_saddr;
 809
 810         if (newsk->sk_prot->init(newsk)) {
 811                 sk_common_release(newsk);
 812                 newsk = NULL;
 813         }
 814
 815 out:
 816         return newsk;
 817 }
 818
 819 /* Format a sockaddr for return to user space. This makes sure the return is
 820  * AF_INET or AF_INET6 depending on the SCTP_I_WANT_MAPPED_V4_ADDR option.
 821  */
 822 static int sctp_v6_addr_to_user(struct sctp_sock *sp, union sctp_addr *addr)
 823 {
 824         if (sp->v4mapped) {
 825                 if (addr->sa.sa_family == AF_INET)
 826                         sctp_v4_map_v6(addr);
 827         } else {
 828                 if (addr->sa.sa_family == AF_INET6 &&
 829                     ipv6_addr_v4mapped(&addr->v6.sin6_addr))
 830                         sctp_v6_map_v4(addr);
 831         }
 832
 833         if (addr->sa.sa_family == AF_INET) {
 834                 memset(addr->v4.sin_zero, 0, sizeof(addr->v4.sin_zero));
 835                 return sizeof(struct sockaddr_in);
 836         }
 837         return sizeof(struct sockaddr_in6);
 838 }
 839
 840 /* Where did this skb come from?  */
 841 static int sctp_v6_skb_iif(const struct sk_buff *skb)
 842 {
 843         return inet6_iif(skb);
 844 }
 845
 846 static int sctp_v6_skb_sdif(const struct sk_buff *skb)
 847 {
 848         return inet6_sdif(skb);
 849 }
 850
 851 /* Was this packet marked by Explicit Congestion Notification? */
 852 static int sctp_v6_is_ce(const struct sk_buff *skb)
 853 {
 854         return *((__u32 *)(ipv6_hdr(skb))) & (__force __u32)htonl(1 << 20);
 855 }
 856
 857 /* Dump the v6 addr to the seq file. */
 858 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
 859 {
 860         seq_printf(seq, "%pI6 ", &addr->v6.sin6_addr);
 861 }
 862
 863 static void sctp_v6_ecn_capable(struct sock *sk)
 864 {
 865         inet6_sk(sk)->tclass |= INET_ECN_ECT_0;
 866 }
 867
 868 /* Initialize a PF_INET msgname from a ulpevent. */
 869 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
 870                                      char *msgname, int *addrlen)
 871 {
 872         union sctp_addr *addr;
 873         struct sctp_association *asoc;
 874         union sctp_addr *paddr;
 875
 876         if (!msgname)
 877                 return;
 878
 879         addr = (union sctp_addr *)msgname;
 880         asoc = event->asoc;
 881         paddr = &asoc->peer.primary_addr;
 882
 883         if (paddr->sa.sa_family == AF_INET) {
 884                 addr->v4.sin_family = AF_INET;
 885                 addr->v4.sin_port = htons(asoc->peer.port);
 886                 addr->v4.sin_addr = paddr->v4.sin_addr;
 887         } else {
 888                 addr->v6.sin6_family = AF_INET6;
 889                 addr->v6.sin6_flowinfo = 0;
 890                 if (ipv6_addr_type(&paddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
 891                         addr->v6.sin6_scope_id = paddr->v6.sin6_scope_id;
 892                 else
 893                         addr->v6.sin6_scope_id = 0;
 894                 addr->v6.sin6_port = htons(asoc->peer.port);
 895                 addr->v6.sin6_addr = paddr->v6.sin6_addr;
 896         }
 897
 898         *addrlen = sctp_v6_addr_to_user(sctp_sk(asoc->base.sk), addr);
 899 }
 900
 901 /* Initialize a msg_name from an inbound skb. */
 902 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
 903                                    int *addr_len)
 904 {
 905         union sctp_addr *addr;
 906         struct sctphdr *sh;
 907
 908         if (!msgname)
 909                 return;
 910
 911         addr = (union sctp_addr *)msgname;
 912         sh = sctp_hdr(skb);
 913
 914         if (ip_hdr(skb)->version == 4) {
 915                 addr->v4.sin_family = AF_INET;
 916                 addr->v4.sin_port = sh->source;
 917                 addr->v4.sin_addr.s_addr = ip_hdr(skb)->saddr;
 918         } else {
 919                 addr->v6.sin6_family = AF_INET6;
 920                 addr->v6.sin6_flowinfo = 0;
 921                 addr->v6.sin6_port = sh->source;
 922                 addr->v6.sin6_addr = ipv6_hdr(skb)->saddr;
 923                 if (ipv6_addr_type(&addr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
 924                         addr->v6.sin6_scope_id = sctp_v6_skb_iif(skb);
 925                 else
 926                         addr->v6.sin6_scope_id = 0;
 927         }
 928
 929         *addr_len = sctp_v6_addr_to_user(sctp_sk(skb->sk), addr);
 930 }
 931
 932 /* Do we support this AF? */
 933 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
 934 {
 935         switch (family) {
 936         case AF_INET6:
 937                 return 1;
 938         /* v4-mapped-v6 addresses */
 939         case AF_INET:
 940                 if (!ipv6_only_sock(sctp_opt2sk(sp)))
 941                         return 1;
 942                 fallthrough;
 943         default:
 944                 return 0;
 945         }
 946 }
 947
 948 /* Address matching with wildcards allowed.  This extra level
 949  * of indirection lets us choose whether a PF_INET6 should
 950  * disallow any v4 addresses if we so choose.
 951  */
 952 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
 953                                const union sctp_addr *addr2,
 954                                struct sctp_sock *opt)
 955 {
 956         struct sock *sk = sctp_opt2sk(opt);
 957         struct sctp_af *af1, *af2;
 958
 959         af1 = sctp_get_af_specific(addr1->sa.sa_family);
 960         af2 = sctp_get_af_specific(addr2->sa.sa_family);
 961
 962         if (!af1 || !af2)
 963                 return 0;
 964
 965         /* If the socket is IPv6 only, v4 addrs will not match */
 966         if (ipv6_only_sock(sk) && af1 != af2)
 967                 return 0;
 968
 969         /* Today, wildcard AF_INET/AF_INET6. */
 970         if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2))
 971                 return 1;
 972
 973         if (addr1->sa.sa_family == AF_INET && addr2->sa.sa_family == AF_INET)
 974                 return addr1->v4.sin_addr.s_addr == addr2->v4.sin_addr.s_addr;
 975
 976         return __sctp_v6_cmp_addr(addr1, addr2);
 977 }
 978
 979 /* Verify that the provided sockaddr looks bindable.   Common verification,
 980  * has already been taken care of.
 981  */
 982 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
 983 {
 984         struct sctp_af *af;
 985
 986         /* ASSERT: address family has already been verified. */
 987         if (addr->sa.sa_family != AF_INET6)
 988                 af = sctp_get_af_specific(addr->sa.sa_family);
 989         else {
 990                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
 991                 struct net_device *dev;
 992
 993                 if (type & IPV6_ADDR_LINKLOCAL) {
 994                         struct net *net;
 995                         if (!addr->v6.sin6_scope_id)
 996                                 return 0;
 997                         net = sock_net(&opt->inet.sk);
 998                         rcu_read_lock();
 999                         dev = dev_get_by_index_rcu(net, addr->v6.sin6_scope_id);
1000                         if (!dev || !(ipv6_can_nonlocal_bind(net, &opt->inet) ||
1001                                       ipv6_chk_addr(net, &addr->v6.sin6_addr,
1002                                                     dev, 0))) {
1003                                 rcu_read_unlock();
1004                                 return 0;
1005                         }
1006                         rcu_read_unlock();
1007                 }
1008
1009                 af = opt->pf->af;
1010         }
1011         return af->available(addr, opt);
1012 }
1013
1014 /* Verify that the provided sockaddr looks sendable.   Common verification,
1015  * has already been taken care of.
1016  */
1017 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
1018 {
1019         struct sctp_af *af = NULL;
1020
1021         /* ASSERT: address family has already been verified. */
1022         if (addr->sa.sa_family != AF_INET6)
1023                 af = sctp_get_af_specific(addr->sa.sa_family);
1024         else {
1025                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
1026                 struct net_device *dev;
1027
1028                 if (type & IPV6_ADDR_LINKLOCAL) {
1029                         if (!addr->v6.sin6_scope_id)
1030                                 return 0;
1031                         rcu_read_lock();
1032                         dev = dev_get_by_index_rcu(sock_net(&opt->inet.sk),
1033                                                    addr->v6.sin6_scope_id);
1034                         rcu_read_unlock();
1035                         if (!dev)
1036                                 return 0;
1037                 }
1038                 af = opt->pf->af;
1039         }
1040
1041         return af != NULL;
1042 }
1043
1044 /* Fill in Supported Address Type information for INIT and INIT-ACK
1045  * chunks.   Note: In the future, we may want to look at sock options
1046  * to determine whether a PF_INET6 socket really wants to have IPV4
1047  * addresses.
1048  * Returns number of addresses supported.
1049  */
1050 static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
1051                                       __be16 *types)
1052 {
1053         types[0] = SCTP_PARAM_IPV6_ADDRESS;
1054         if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) {
1055                 types[1] = SCTP_PARAM_IPV4_ADDRESS;
1056                 return 2;
1057         }
1058         return 1;
1059 }
1060
1061 /* Handle SCTP_I_WANT_MAPPED_V4_ADDR for getpeername() and getsockname() */
1062 static int sctp_getname(struct socket *sock, struct sockaddr *uaddr,
1063                         int peer)
1064 {
1065         int rc;
1066
1067         rc = inet6_getname(sock, uaddr, peer);
1068
1069         if (rc < 0)
1070                 return rc;
1071
1072         rc = sctp_v6_addr_to_user(sctp_sk(sock->sk),
1073                                           (union sctp_addr *)uaddr);
1074
1075         return rc;
1076 }
1077
1078 static const struct proto_ops inet6_seqpacket_ops = {
1079         .family            = PF_INET6,
1080         .owner             = THIS_MODULE,
1081         .release           = inet6_release,
1082         .bind              = inet6_bind,
1083         .connect           = sctp_inet_connect,
1084         .socketpair        = sock_no_socketpair,
1085         .accept            = inet_accept,
1086         .getname           = sctp_getname,
1087         .poll              = sctp_poll,
1088         .ioctl             = inet6_ioctl,
1089         .gettstamp         = sock_gettstamp,
1090         .listen            = sctp_inet_listen,
1091         .shutdown          = inet_shutdown,
1092         .setsockopt        = sock_common_setsockopt,
1093         .getsockopt        = sock_common_getsockopt,
1094         .sendmsg           = inet_sendmsg,
1095         .recvmsg           = inet_recvmsg,
1096         .mmap              = sock_no_mmap,
1097 #ifdef CONFIG_COMPAT
1098         .compat_ioctl      = inet6_compat_ioctl,
1099 #endif
1100 };
1101
1102 static struct inet_protosw sctpv6_seqpacket_protosw = {
1103         .type          = SOCK_SEQPACKET,
1104         .protocol      = IPPROTO_SCTP,
1105         .prot          = &sctpv6_prot,
1106         .ops           = &inet6_seqpacket_ops,
1107         .flags         = SCTP_PROTOSW_FLAG
1108 };
1109 static struct inet_protosw sctpv6_stream_protosw = {
1110         .type          = SOCK_STREAM,
1111         .protocol      = IPPROTO_SCTP,
1112         .prot          = &sctpv6_prot,
1113         .ops           = &inet6_seqpacket_ops,
1114         .flags         = SCTP_PROTOSW_FLAG,
1115 };
1116
1117 static int sctp6_rcv(struct sk_buff *skb)
1118 {
1119         SCTP_INPUT_CB(skb)->encap_port = 0;
1120         return sctp_rcv(skb) ? -1 : 0;
1121 }
1122
1123 static const struct inet6_protocol sctpv6_protocol = {
1124         .handler      = sctp6_rcv,
1125         .err_handler  = sctp_v6_err,
1126         .flags        = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
1127 };
1128
1129 static struct sctp_af sctp_af_inet6 = {
1130         .sa_family         = AF_INET6,
1131         .sctp_xmit         = sctp_v6_xmit,
1132         .setsockopt        = ipv6_setsockopt,
1133         .getsockopt        = ipv6_getsockopt,
1134         .get_dst           = sctp_v6_get_dst,
1135         .get_saddr         = sctp_v6_get_saddr,
1136         .copy_addrlist     = sctp_v6_copy_addrlist,
1137         .from_skb          = sctp_v6_from_skb,
1138         .from_sk           = sctp_v6_from_sk,
1139         .from_addr_param   = sctp_v6_from_addr_param,
1140         .to_addr_param     = sctp_v6_to_addr_param,
1141         .cmp_addr          = sctp_v6_cmp_addr,
1142         .scope             = sctp_v6_scope,
1143         .addr_valid        = sctp_v6_addr_valid,
1144         .inaddr_any        = sctp_v6_inaddr_any,
1145         .is_any            = sctp_v6_is_any,
1146         .available         = sctp_v6_available,
1147         .skb_iif           = sctp_v6_skb_iif,
1148         .skb_sdif          = sctp_v6_skb_sdif,
1149         .is_ce             = sctp_v6_is_ce,
1150         .seq_dump_addr     = sctp_v6_seq_dump_addr,
1151         .ecn_capable       = sctp_v6_ecn_capable,
1152         .net_header_len    = sizeof(struct ipv6hdr),
1153         .sockaddr_len      = sizeof(struct sockaddr_in6),
1154         .ip_options_len    = sctp_v6_ip_options_len,
1155 };
1156
1157 static struct sctp_pf sctp_pf_inet6 = {
1158         .event_msgname = sctp_inet6_event_msgname,
1159         .skb_msgname   = sctp_inet6_skb_msgname,
1160         .af_supported  = sctp_inet6_af_supported,
1161         .cmp_addr      = sctp_inet6_cmp_addr,
1162         .bind_verify   = sctp_inet6_bind_verify,
1163         .send_verify   = sctp_inet6_send_verify,
1164         .supported_addrs = sctp_inet6_supported_addrs,
1165         .create_accept_sk = sctp_v6_create_accept_sk,
1166         .addr_to_user  = sctp_v6_addr_to_user,
1167         .to_sk_saddr   = sctp_v6_to_sk_saddr,
1168         .to_sk_daddr   = sctp_v6_to_sk_daddr,
1169         .copy_ip_options = sctp_v6_copy_ip_options,
1170         .af            = &sctp_af_inet6,
1171 };
1172
1173 /* Initialize IPv6 support and register with socket layer.  */
1174 void sctp_v6_pf_init(void)
1175 {
1176         /* Register the SCTP specific PF_INET6 functions. */
1177         sctp_register_pf(&sctp_pf_inet6, PF_INET6);
1178
1179         /* Register the SCTP specific AF_INET6 functions. */
1180         sctp_register_af(&sctp_af_inet6);
1181 }
1182
1183 void sctp_v6_pf_exit(void)
1184 {
1185         list_del(&sctp_af_inet6.list);
1186 }
1187
1188 /* Initialize IPv6 support and register with socket layer.  */
1189 int sctp_v6_protosw_init(void)
1190 {
1191         int rc;
1192
1193         rc = proto_register(&sctpv6_prot, 1);
1194         if (rc)
1195                 return rc;
1196
1197         /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
1198         inet6_register_protosw(&sctpv6_seqpacket_protosw);
1199         inet6_register_protosw(&sctpv6_stream_protosw);
1200
1201         return 0;
1202 }
1203
1204 void sctp_v6_protosw_exit(void)
1205 {
1206         inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
1207         inet6_unregister_protosw(&sctpv6_stream_protosw);
1208         proto_unregister(&sctpv6_prot);
1209 }
1210
1211
1212 /* Register with inet6 layer. */
1213 int sctp_v6_add_protocol(void)
1214 {
1215         /* Register notifier for inet6 address additions/deletions. */
1216         register_inet6addr_notifier(&sctp_inet6addr_notifier);
1217
1218         if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
1219                 return -EAGAIN;
1220
1221         return 0;
1222 }
1223
1224 /* Unregister with inet6 layer. */
1225 void sctp_v6_del_protocol(void)
1226 {
1227         inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
1228         unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1229 }