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, write to
  25  * the Free Software Foundation, 59 Temple Place - Suite 330,
  26  * Boston, MA 02111-1307, USA.
  27  *
  28  * Please send any bug reports or fixes you make to the
  29  * email address(es):
  30  *    lksctp developers <lksctp-developers@lists.sourceforge.net>
  31  *
  32  * Or submit a bug report through the following website:
  33  *    http://www.sf.net/projects/lksctp
  34  *
  35  * Written or modified by:
  36  *    Le Yanqun             <yanqun.le@nokia.com>
  37  *    Hui Huang             <hui.huang@nokia.com>
  38  *    La Monte H.P. Yarroll <piggy@acm.org>
  39  *    Sridhar Samudrala     <sri@us.ibm.com>
  40  *    Jon Grimm             <jgrimm@us.ibm.com>
  41  *    Ardelle Fan           <ardelle.fan@intel.com>
  42  *
  43  * Based on:
  44  *      linux/net/ipv6/tcp_ipv6.c
  45  *
  46  * Any bugs reported given to us we will try to fix... any fixes shared will
  47  * be incorporated into the next SCTP release.
  48  */
  49
  50 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  51
  52 #include <linux/module.h>
  53 #include <linux/errno.h>
  54 #include <linux/types.h>
  55 #include <linux/socket.h>
  56 #include <linux/sockios.h>
  57 #include <linux/net.h>
  58 #include <linux/in.h>
  59 #include <linux/in6.h>
  60 #include <linux/netdevice.h>
  61 #include <linux/init.h>
  62 #include <linux/ipsec.h>
  63 #include <linux/slab.h>
  64
  65 #include <linux/ipv6.h>
  66 #include <linux/icmpv6.h>
  67 #include <linux/random.h>
  68 #include <linux/seq_file.h>
  69
  70 #include <net/protocol.h>
  71 #include <net/ndisc.h>
  72 #include <net/ip.h>
  73 #include <net/ipv6.h>
  74 #include <net/transp_v6.h>
  75 #include <net/addrconf.h>
  76 #include <net/ip6_route.h>
  77 #include <net/inet_common.h>
  78 #include <net/inet_ecn.h>
  79 #include <net/sctp/sctp.h>
  80
  81 #include <asm/uaccess.h>
  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         int found = 0;
  96
  97         switch (ev) {
  98         case NETDEV_UP:
  99                 addr = kmalloc(sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC);
 100                 if (addr) {
 101                         addr->a.v6.sin6_family = AF_INET6;
 102                         addr->a.v6.sin6_port = 0;
 103                         ipv6_addr_copy(&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(&sctp_local_addr_lock);
 107                         list_add_tail_rcu(&addr->list, &sctp_local_addr_list);
 108                         spin_unlock_bh(&sctp_local_addr_lock);
 109                 }
 110                 break;
 111         case NETDEV_DOWN:
 112                 spin_lock_bh(&sctp_local_addr_lock);
 113                 list_for_each_entry_safe(addr, temp,
 114                                         &sctp_local_addr_list, list) {
 115                         if (addr->a.sa.sa_family == AF_INET6 &&
 116                                         ipv6_addr_equal(&addr->a.v6.sin6_addr,
 117                                                 &ifa->addr)) {
 118                                 found = 1;
 119                                 addr->valid = 0;
 120                                 list_del_rcu(&addr->list);
 121                                 break;
 122                         }
 123                 }
 124                 spin_unlock_bh(&sctp_local_addr_lock);
 125                 if (found)
 126                         call_rcu(&addr->rcu, sctp_local_addr_free);
 127                 break;
 128         }
 129
 130         return NOTIFY_DONE;
 131 }
 132
 133 static struct notifier_block sctp_inet6addr_notifier = {
 134         .notifier_call = sctp_inet6addr_event,
 135 };
 136
 137 /* ICMP error handler. */
 138 SCTP_STATIC void sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 139                              u8 type, u8 code, int offset, __be32 info)
 140 {
 141         struct inet6_dev *idev;
 142         struct sock *sk;
 143         struct sctp_association *asoc;
 144         struct sctp_transport *transport;
 145         struct ipv6_pinfo *np;
 146         sk_buff_data_t saveip, savesctp;
 147         int err;
 148
 149         idev = in6_dev_get(skb->dev);
 150
 151         /* Fix up skb to look at the embedded net header. */
 152         saveip   = skb->network_header;
 153         savesctp = skb->transport_header;
 154         skb_reset_network_header(skb);
 155         skb_set_transport_header(skb, offset);
 156         sk = sctp_err_lookup(AF_INET6, skb, sctp_hdr(skb), &asoc, &transport);
 157         /* Put back, the original pointers. */
 158         skb->network_header   = saveip;
 159         skb->transport_header = savesctp;
 160         if (!sk) {
 161                 ICMP6_INC_STATS_BH(dev_net(skb->dev), idev, ICMP6_MIB_INERRORS);
 162                 goto out;
 163         }
 164
 165         /* Warning:  The sock lock is held.  Remember to call
 166          * sctp_err_finish!
 167          */
 168
 169         switch (type) {
 170         case ICMPV6_PKT_TOOBIG:
 171                 sctp_icmp_frag_needed(sk, asoc, transport, ntohl(info));
 172                 goto out_unlock;
 173         case ICMPV6_PARAMPROB:
 174                 if (ICMPV6_UNK_NEXTHDR == code) {
 175                         sctp_icmp_proto_unreachable(sk, asoc, transport);
 176                         goto out_unlock;
 177                 }
 178                 break;
 179         default:
 180                 break;
 181         }
 182
 183         np = inet6_sk(sk);
 184         icmpv6_err_convert(type, code, &err);
 185         if (!sock_owned_by_user(sk) && np->recverr) {
 186                 sk->sk_err = err;
 187                 sk->sk_error_report(sk);
 188         } else {  /* Only an error on timeout */
 189                 sk->sk_err_soft = err;
 190         }
 191
 192 out_unlock:
 193         sctp_err_finish(sk, asoc);
 194 out:
 195         if (likely(idev != NULL))
 196                 in6_dev_put(idev);
 197 }
 198
 199 /* Based on tcp_v6_xmit() in tcp_ipv6.c. */
 200 static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *transport)
 201 {
 202         struct sock *sk = skb->sk;
 203         struct ipv6_pinfo *np = inet6_sk(sk);
 204         struct flowi fl;
 205
 206         memset(&fl, 0, sizeof(fl));
 207
 208         fl.proto = sk->sk_protocol;
 209
 210         /* Fill in the dest address from the route entry passed with the skb
 211          * and the source address from the transport.
 212          */
 213         ipv6_addr_copy(&fl.fl6_dst, &transport->ipaddr.v6.sin6_addr);
 214         ipv6_addr_copy(&fl.fl6_src, &transport->saddr.v6.sin6_addr);
 215
 216         fl.fl6_flowlabel = np->flow_label;
 217         IP6_ECN_flow_xmit(sk, fl.fl6_flowlabel);
 218         if (ipv6_addr_type(&fl.fl6_src) & IPV6_ADDR_LINKLOCAL)
 219                 fl.oif = transport->saddr.v6.sin6_scope_id;
 220         else
 221                 fl.oif = sk->sk_bound_dev_if;
 222
 223         if (np->opt && np->opt->srcrt) {
 224                 struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
 225                 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
 226         }
 227
 228         SCTP_DEBUG_PRINTK("%s: skb:%p, len:%d, src:%pI6 dst:%pI6\n",
 229                           __func__, skb, skb->len,
 230                           &fl.fl6_src, &fl.fl6_dst);
 231
 232         SCTP_INC_STATS(SCTP_MIB_OUTSCTPPACKS);
 233
 234         if (!(transport->param_flags & SPP_PMTUD_ENABLE))
 235                 skb->local_df = 1;
 236
 237         return ip6_xmit(sk, skb, &fl, np->opt);
 238 }
 239
 240 /* Returns the dst cache entry for the given source and destination ip
 241  * addresses.
 242  */
 243 static struct dst_entry *sctp_v6_get_dst(struct sctp_association *asoc,
 244                                          union sctp_addr *daddr,
 245                                          union sctp_addr *saddr)
 246 {
 247         struct dst_entry *dst;
 248         struct flowi fl;
 249
 250         memset(&fl, 0, sizeof(fl));
 251         ipv6_addr_copy(&fl.fl6_dst, &daddr->v6.sin6_addr);
 252         if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
 253                 fl.oif = daddr->v6.sin6_scope_id;
 254
 255
 256         SCTP_DEBUG_PRINTK("%s: DST=%pI6 ", __func__, &fl.fl6_dst);
 257
 258         if (saddr) {
 259                 ipv6_addr_copy(&fl.fl6_src, &saddr->v6.sin6_addr);
 260                 SCTP_DEBUG_PRINTK("SRC=%pI6 - ", &fl.fl6_src);
 261         }
 262
 263         dst = ip6_route_output(&init_net, NULL, &fl);
 264         if (!dst->error) {
 265                 struct rt6_info *rt;
 266                 rt = (struct rt6_info *)dst;
 267                 SCTP_DEBUG_PRINTK("rt6_dst:%pI6 rt6_src:%pI6\n",
 268                         &rt->rt6i_dst.addr, &rt->rt6i_src.addr);
 269                 return dst;
 270         }
 271         SCTP_DEBUG_PRINTK("NO ROUTE\n");
 272         dst_release(dst);
 273         return NULL;
 274 }
 275
 276 /* Returns the number of consecutive initial bits that match in the 2 ipv6
 277  * addresses.
 278  */
 279 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
 280                                          union sctp_addr *s2)
 281 {
 282         return ipv6_addr_diff(&s1->v6.sin6_addr, &s2->v6.sin6_addr);
 283 }
 284
 285 /* Fills in the source address(saddr) based on the destination address(daddr)
 286  * and asoc's bind address list.
 287  */
 288 static void sctp_v6_get_saddr(struct sctp_sock *sk,
 289                               struct sctp_association *asoc,
 290                               struct dst_entry *dst,
 291                               union sctp_addr *daddr,
 292                               union sctp_addr *saddr)
 293 {
 294         struct sctp_bind_addr *bp;
 295         struct sctp_sockaddr_entry *laddr;
 296         sctp_scope_t scope;
 297         union sctp_addr *baddr = NULL;
 298         __u8 matchlen = 0;
 299         __u8 bmatchlen;
 300
 301         SCTP_DEBUG_PRINTK("%s: asoc:%p dst:%p daddr:%pI6 ",
 302                           __func__, asoc, dst, &daddr->v6.sin6_addr);
 303
 304         if (!asoc) {
 305                 ipv6_dev_get_saddr(sock_net(sctp_opt2sk(sk)),
 306                                    dst ? ip6_dst_idev(dst)->dev : NULL,
 307                                    &daddr->v6.sin6_addr,
 308                                    inet6_sk(&sk->inet.sk)->srcprefs,
 309                                    &saddr->v6.sin6_addr);
 310                 SCTP_DEBUG_PRINTK("saddr from ipv6_get_saddr: %pI6\n",
 311                                   &saddr->v6.sin6_addr);
 312                 return;
 313         }
 314
 315         scope = sctp_scope(daddr);
 316
 317         bp = &asoc->base.bind_addr;
 318
 319         /* Go through the bind address list and find the best source address
 320          * that matches the scope of the destination address.
 321          */
 322         rcu_read_lock();
 323         list_for_each_entry_rcu(laddr, &bp->address_list, list) {
 324                 if (!laddr->valid)
 325                         continue;
 326                 if ((laddr->state == SCTP_ADDR_SRC) &&
 327                     (laddr->a.sa.sa_family == AF_INET6) &&
 328                     (scope <= sctp_scope(&laddr->a))) {
 329                         bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
 330                         if (!baddr || (matchlen < bmatchlen)) {
 331                                 baddr = &laddr->a;
 332                                 matchlen = bmatchlen;
 333                         }
 334                 }
 335         }
 336
 337         if (baddr) {
 338                 memcpy(saddr, baddr, sizeof(union sctp_addr));
 339                 SCTP_DEBUG_PRINTK("saddr: %pI6\n", &saddr->v6.sin6_addr);
 340         } else {
 341                 pr_err("%s: asoc:%p Could not find a valid source "
 342                        "address for the dest:%pI6\n",
 343                        __func__, asoc, &daddr->v6.sin6_addr);
 344         }
 345
 346         rcu_read_unlock();
 347 }
 348
 349 /* Make a copy of all potential local addresses. */
 350 static void sctp_v6_copy_addrlist(struct list_head *addrlist,
 351                                   struct net_device *dev)
 352 {
 353         struct inet6_dev *in6_dev;
 354         struct inet6_ifaddr *ifp;
 355         struct sctp_sockaddr_entry *addr;
 356
 357         rcu_read_lock();
 358         if ((in6_dev = __in6_dev_get(dev)) == NULL) {
 359                 rcu_read_unlock();
 360                 return;
 361         }
 362
 363         read_lock_bh(&in6_dev->lock);
 364         list_for_each_entry(ifp, &in6_dev->addr_list, if_list) {
 365                 /* Add the address to the local list.  */
 366                 addr = t_new(struct sctp_sockaddr_entry, GFP_ATOMIC);
 367                 if (addr) {
 368                         addr->a.v6.sin6_family = AF_INET6;
 369                         addr->a.v6.sin6_port = 0;
 370                         ipv6_addr_copy(&addr->a.v6.sin6_addr, &ifp->addr);
 371                         addr->a.v6.sin6_scope_id = dev->ifindex;
 372                         addr->valid = 1;
 373                         INIT_LIST_HEAD(&addr->list);
 374                         list_add_tail(&addr->list, addrlist);
 375                 }
 376         }
 377
 378         read_unlock_bh(&in6_dev->lock);
 379         rcu_read_unlock();
 380 }
 381
 382 /* Initialize a sockaddr_storage from in incoming skb. */
 383 static void sctp_v6_from_skb(union sctp_addr *addr,struct sk_buff *skb,
 384                              int is_saddr)
 385 {
 386         void *from;
 387         __be16 *port;
 388         struct sctphdr *sh;
 389
 390         port = &addr->v6.sin6_port;
 391         addr->v6.sin6_family = AF_INET6;
 392         addr->v6.sin6_flowinfo = 0; /* FIXME */
 393         addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif;
 394
 395         sh = sctp_hdr(skb);
 396         if (is_saddr) {
 397                 *port  = sh->source;
 398                 from = &ipv6_hdr(skb)->saddr;
 399         } else {
 400                 *port = sh->dest;
 401                 from = &ipv6_hdr(skb)->daddr;
 402         }
 403         ipv6_addr_copy(&addr->v6.sin6_addr, from);
 404 }
 405
 406 /* Initialize an sctp_addr from a socket. */
 407 static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
 408 {
 409         addr->v6.sin6_family = AF_INET6;
 410         addr->v6.sin6_port = 0;
 411         ipv6_addr_copy(&addr->v6.sin6_addr, &inet6_sk(sk)->rcv_saddr);
 412 }
 413
 414 /* Initialize sk->sk_rcv_saddr from sctp_addr. */
 415 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
 416 {
 417         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
 418                 inet6_sk(sk)->rcv_saddr.s6_addr32[0] = 0;
 419                 inet6_sk(sk)->rcv_saddr.s6_addr32[1] = 0;
 420                 inet6_sk(sk)->rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
 421                 inet6_sk(sk)->rcv_saddr.s6_addr32[3] =
 422                         addr->v4.sin_addr.s_addr;
 423         } else {
 424                 ipv6_addr_copy(&inet6_sk(sk)->rcv_saddr, &addr->v6.sin6_addr);
 425         }
 426 }
 427
 428 /* Initialize sk->sk_daddr from sctp_addr. */
 429 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
 430 {
 431         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
 432                 inet6_sk(sk)->daddr.s6_addr32[0] = 0;
 433                 inet6_sk(sk)->daddr.s6_addr32[1] = 0;
 434                 inet6_sk(sk)->daddr.s6_addr32[2] = htonl(0x0000ffff);
 435                 inet6_sk(sk)->daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
 436         } else {
 437                 ipv6_addr_copy(&inet6_sk(sk)->daddr, &addr->v6.sin6_addr);
 438         }
 439 }
 440
 441 /* Initialize a sctp_addr from an address parameter. */
 442 static void sctp_v6_from_addr_param(union sctp_addr *addr,
 443                                     union sctp_addr_param *param,
 444                                     __be16 port, int iif)
 445 {
 446         addr->v6.sin6_family = AF_INET6;
 447         addr->v6.sin6_port = port;
 448         addr->v6.sin6_flowinfo = 0; /* BUG */
 449         ipv6_addr_copy(&addr->v6.sin6_addr, &param->v6.addr);
 450         addr->v6.sin6_scope_id = iif;
 451 }
 452
 453 /* Initialize an address parameter from a sctp_addr and return the length
 454  * of the address parameter.
 455  */
 456 static int sctp_v6_to_addr_param(const union sctp_addr *addr,
 457                                  union sctp_addr_param *param)
 458 {
 459         int length = sizeof(sctp_ipv6addr_param_t);
 460
 461         param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
 462         param->v6.param_hdr.length = htons(length);
 463         ipv6_addr_copy(&param->v6.addr, &addr->v6.sin6_addr);
 464
 465         return length;
 466 }
 467
 468 /* Initialize a sctp_addr from a dst_entry. */
 469 static void sctp_v6_dst_saddr(union sctp_addr *addr, struct dst_entry *dst,
 470                               __be16 port)
 471 {
 472         struct rt6_info *rt = (struct rt6_info *)dst;
 473         addr->sa.sa_family = AF_INET6;
 474         addr->v6.sin6_port = port;
 475         ipv6_addr_copy(&addr->v6.sin6_addr, &rt->rt6i_src.addr);
 476 }
 477
 478 /* Compare addresses exactly.
 479  * v4-mapped-v6 is also in consideration.
 480  */
 481 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
 482                             const union sctp_addr *addr2)
 483 {
 484         if (addr1->sa.sa_family != addr2->sa.sa_family) {
 485                 if (addr1->sa.sa_family == AF_INET &&
 486                     addr2->sa.sa_family == AF_INET6 &&
 487                     ipv6_addr_v4mapped(&addr2->v6.sin6_addr)) {
 488                         if (addr2->v6.sin6_port == addr1->v4.sin_port &&
 489                             addr2->v6.sin6_addr.s6_addr32[3] ==
 490                             addr1->v4.sin_addr.s_addr)
 491                                 return 1;
 492                 }
 493                 if (addr2->sa.sa_family == AF_INET &&
 494                     addr1->sa.sa_family == AF_INET6 &&
 495                     ipv6_addr_v4mapped(&addr1->v6.sin6_addr)) {
 496                         if (addr1->v6.sin6_port == addr2->v4.sin_port &&
 497                             addr1->v6.sin6_addr.s6_addr32[3] ==
 498                             addr2->v4.sin_addr.s_addr)
 499                                 return 1;
 500                 }
 501                 return 0;
 502         }
 503         if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
 504                 return 0;
 505         /* If this is a linklocal address, compare the scope_id. */
 506         if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) {
 507                 if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
 508                     (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) {
 509                         return 0;
 510                 }
 511         }
 512
 513         return 1;
 514 }
 515
 516 /* Initialize addr struct to INADDR_ANY. */
 517 static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port)
 518 {
 519         memset(addr, 0x00, sizeof(union sctp_addr));
 520         addr->v6.sin6_family = AF_INET6;
 521         addr->v6.sin6_port = port;
 522 }
 523
 524 /* Is this a wildcard address? */
 525 static int sctp_v6_is_any(const union sctp_addr *addr)
 526 {
 527         return ipv6_addr_any(&addr->v6.sin6_addr);
 528 }
 529
 530 /* Should this be available for binding?   */
 531 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
 532 {
 533         int type;
 534         struct in6_addr *in6 = (struct in6_addr *)&addr->v6.sin6_addr;
 535
 536         type = ipv6_addr_type(in6);
 537         if (IPV6_ADDR_ANY == type)
 538                 return 1;
 539         if (type == IPV6_ADDR_MAPPED) {
 540                 if (sp && !sp->v4mapped)
 541                         return 0;
 542                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
 543                         return 0;
 544                 sctp_v6_map_v4(addr);
 545                 return sctp_get_af_specific(AF_INET)->available(addr, sp);
 546         }
 547         if (!(type & IPV6_ADDR_UNICAST))
 548                 return 0;
 549
 550         return ipv6_chk_addr(&init_net, in6, NULL, 0);
 551 }
 552
 553 /* This function checks if the address is a valid address to be used for
 554  * SCTP.
 555  *
 556  * Output:
 557  * Return 0 - If the address is a non-unicast or an illegal address.
 558  * Return 1 - If the address is a unicast.
 559  */
 560 static int sctp_v6_addr_valid(union sctp_addr *addr,
 561                               struct sctp_sock *sp,
 562                               const struct sk_buff *skb)
 563 {
 564         int ret = ipv6_addr_type(&addr->v6.sin6_addr);
 565
 566         /* Support v4-mapped-v6 address. */
 567         if (ret == IPV6_ADDR_MAPPED) {
 568                 /* Note: This routine is used in input, so v4-mapped-v6
 569                  * are disallowed here when there is no sctp_sock.
 570                  */
 571                 if (!sp || !sp->v4mapped)
 572                         return 0;
 573                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
 574                         return 0;
 575                 sctp_v6_map_v4(addr);
 576                 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb);
 577         }
 578
 579         /* Is this a non-unicast address */
 580         if (!(ret & IPV6_ADDR_UNICAST))
 581                 return 0;
 582
 583         return 1;
 584 }
 585
 586 /* What is the scope of 'addr'?  */
 587 static sctp_scope_t sctp_v6_scope(union sctp_addr *addr)
 588 {
 589         int v6scope;
 590         sctp_scope_t retval;
 591
 592         /* The IPv6 scope is really a set of bit fields.
 593          * See IFA_* in <net/if_inet6.h>.  Map to a generic SCTP scope.
 594          */
 595
 596         v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
 597         switch (v6scope) {
 598         case IFA_HOST:
 599                 retval = SCTP_SCOPE_LOOPBACK;
 600                 break;
 601         case IFA_LINK:
 602                 retval = SCTP_SCOPE_LINK;
 603                 break;
 604         case IFA_SITE:
 605                 retval = SCTP_SCOPE_PRIVATE;
 606                 break;
 607         default:
 608                 retval = SCTP_SCOPE_GLOBAL;
 609                 break;
 610         }
 611
 612         return retval;
 613 }
 614
 615 /* Create and initialize a new sk for the socket to be returned by accept(). */
 616 static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
 617                                              struct sctp_association *asoc)
 618 {
 619         struct sock *newsk;
 620         struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
 621         struct sctp6_sock *newsctp6sk;
 622
 623         newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot);
 624         if (!newsk)
 625                 goto out;
 626
 627         sock_init_data(NULL, newsk);
 628
 629         sctp_copy_sock(newsk, sk, asoc);
 630         sock_reset_flag(sk, SOCK_ZAPPED);
 631
 632         newsctp6sk = (struct sctp6_sock *)newsk;
 633         inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
 634
 635         sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped;
 636
 637         newnp = inet6_sk(newsk);
 638
 639         memcpy(newnp, np, sizeof(struct ipv6_pinfo));
 640
 641         /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
 642          * and getpeername().
 643          */
 644         sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
 645
 646         sk_refcnt_debug_inc(newsk);
 647
 648         if (newsk->sk_prot->init(newsk)) {
 649                 sk_common_release(newsk);
 650                 newsk = NULL;
 651         }
 652
 653 out:
 654         return newsk;
 655 }
 656
 657 /* Map v4 address to mapped v6 address */
 658 static void sctp_v6_addr_v4map(struct sctp_sock *sp, union sctp_addr *addr)
 659 {
 660         if (sp->v4mapped && AF_INET == addr->sa.sa_family)
 661                 sctp_v4_map_v6(addr);
 662 }
 663
 664 /* Where did this skb come from?  */
 665 static int sctp_v6_skb_iif(const struct sk_buff *skb)
 666 {
 667         struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb;
 668         return opt->iif;
 669 }
 670
 671 /* Was this packet marked by Explicit Congestion Notification? */
 672 static int sctp_v6_is_ce(const struct sk_buff *skb)
 673 {
 674         return *((__u32 *)(ipv6_hdr(skb))) & htonl(1 << 20);
 675 }
 676
 677 /* Dump the v6 addr to the seq file. */
 678 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
 679 {
 680         seq_printf(seq, "%pI6 ", &addr->v6.sin6_addr);
 681 }
 682
 683 static void sctp_v6_ecn_capable(struct sock *sk)
 684 {
 685         inet6_sk(sk)->tclass |= INET_ECN_ECT_0;
 686 }
 687
 688 /* Initialize a PF_INET6 socket msg_name. */
 689 static void sctp_inet6_msgname(char *msgname, int *addr_len)
 690 {
 691         struct sockaddr_in6 *sin6;
 692
 693         sin6 = (struct sockaddr_in6 *)msgname;
 694         sin6->sin6_family = AF_INET6;
 695         sin6->sin6_flowinfo = 0;
 696         sin6->sin6_scope_id = 0; /*FIXME */
 697         *addr_len = sizeof(struct sockaddr_in6);
 698 }
 699
 700 /* Initialize a PF_INET msgname from a ulpevent. */
 701 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
 702                                      char *msgname, int *addrlen)
 703 {
 704         struct sockaddr_in6 *sin6, *sin6from;
 705
 706         if (msgname) {
 707                 union sctp_addr *addr;
 708                 struct sctp_association *asoc;
 709
 710                 asoc = event->asoc;
 711                 sctp_inet6_msgname(msgname, addrlen);
 712                 sin6 = (struct sockaddr_in6 *)msgname;
 713                 sin6->sin6_port = htons(asoc->peer.port);
 714                 addr = &asoc->peer.primary_addr;
 715
 716                 /* Note: If we go to a common v6 format, this code
 717                  * will change.
 718                  */
 719
 720                 /* Map ipv4 address into v4-mapped-on-v6 address.  */
 721                 if (sctp_sk(asoc->base.sk)->v4mapped &&
 722                     AF_INET == addr->sa.sa_family) {
 723                         sctp_v4_map_v6((union sctp_addr *)sin6);
 724                         sin6->sin6_addr.s6_addr32[3] =
 725                                 addr->v4.sin_addr.s_addr;
 726                         return;
 727                 }
 728
 729                 sin6from = &asoc->peer.primary_addr.v6;
 730                 ipv6_addr_copy(&sin6->sin6_addr, &sin6from->sin6_addr);
 731                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 732                         sin6->sin6_scope_id = sin6from->sin6_scope_id;
 733         }
 734 }
 735
 736 /* Initialize a msg_name from an inbound skb. */
 737 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
 738                                    int *addr_len)
 739 {
 740         struct sctphdr *sh;
 741         struct sockaddr_in6 *sin6;
 742
 743         if (msgname) {
 744                 sctp_inet6_msgname(msgname, addr_len);
 745                 sin6 = (struct sockaddr_in6 *)msgname;
 746                 sh = sctp_hdr(skb);
 747                 sin6->sin6_port = sh->source;
 748
 749                 /* Map ipv4 address into v4-mapped-on-v6 address. */
 750                 if (sctp_sk(skb->sk)->v4mapped &&
 751                     ip_hdr(skb)->version == 4) {
 752                         sctp_v4_map_v6((union sctp_addr *)sin6);
 753                         sin6->sin6_addr.s6_addr32[3] = ip_hdr(skb)->saddr;
 754                         return;
 755                 }
 756
 757                 /* Otherwise, just copy the v6 address. */
 758                 ipv6_addr_copy(&sin6->sin6_addr, &ipv6_hdr(skb)->saddr);
 759                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) {
 760                         struct sctp_ulpevent *ev = sctp_skb2event(skb);
 761                         sin6->sin6_scope_id = ev->iif;
 762                 }
 763         }
 764 }
 765
 766 /* Do we support this AF? */
 767 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
 768 {
 769         switch (family) {
 770         case AF_INET6:
 771                 return 1;
 772         /* v4-mapped-v6 addresses */
 773         case AF_INET:
 774                 if (!__ipv6_only_sock(sctp_opt2sk(sp)))
 775                         return 1;
 776         default:
 777                 return 0;
 778         }
 779 }
 780
 781 /* Address matching with wildcards allowed.  This extra level
 782  * of indirection lets us choose whether a PF_INET6 should
 783  * disallow any v4 addresses if we so choose.
 784  */
 785 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
 786                                const union sctp_addr *addr2,
 787                                struct sctp_sock *opt)
 788 {
 789         struct sctp_af *af1, *af2;
 790         struct sock *sk = sctp_opt2sk(opt);
 791
 792         af1 = sctp_get_af_specific(addr1->sa.sa_family);
 793         af2 = sctp_get_af_specific(addr2->sa.sa_family);
 794
 795         if (!af1 || !af2)
 796                 return 0;
 797
 798         /* If the socket is IPv6 only, v4 addrs will not match */
 799         if (__ipv6_only_sock(sk) && af1 != af2)
 800                 return 0;
 801
 802         /* Today, wildcard AF_INET/AF_INET6. */
 803         if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2))
 804                 return 1;
 805
 806         if (addr1->sa.sa_family != addr2->sa.sa_family)
 807                 return 0;
 808
 809         return af1->cmp_addr(addr1, addr2);
 810 }
 811
 812 /* Verify that the provided sockaddr looks bindable.   Common verification,
 813  * has already been taken care of.
 814  */
 815 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
 816 {
 817         struct sctp_af *af;
 818
 819         /* ASSERT: address family has already been verified. */
 820         if (addr->sa.sa_family != AF_INET6)
 821                 af = sctp_get_af_specific(addr->sa.sa_family);
 822         else {
 823                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
 824                 struct net_device *dev;
 825
 826                 if (type & IPV6_ADDR_LINKLOCAL) {
 827                         if (!addr->v6.sin6_scope_id)
 828                                 return 0;
 829                         rcu_read_lock();
 830                         dev = dev_get_by_index_rcu(&init_net,
 831                                                    addr->v6.sin6_scope_id);
 832                         if (!dev ||
 833                             !ipv6_chk_addr(&init_net, &addr->v6.sin6_addr,
 834                                            dev, 0)) {
 835                                 rcu_read_unlock();
 836                                 return 0;
 837                         }
 838                         rcu_read_unlock();
 839                 } else if (type == IPV6_ADDR_MAPPED) {
 840                         if (!opt->v4mapped)
 841                                 return 0;
 842                 }
 843
 844                 af = opt->pf->af;
 845         }
 846         return af->available(addr, opt);
 847 }
 848
 849 /* Verify that the provided sockaddr looks sendable.   Common verification,
 850  * has already been taken care of.
 851  */
 852 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
 853 {
 854         struct sctp_af *af = NULL;
 855
 856         /* ASSERT: address family has already been verified. */
 857         if (addr->sa.sa_family != AF_INET6)
 858                 af = sctp_get_af_specific(addr->sa.sa_family);
 859         else {
 860                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
 861                 struct net_device *dev;
 862
 863                 if (type & IPV6_ADDR_LINKLOCAL) {
 864                         if (!addr->v6.sin6_scope_id)
 865                                 return 0;
 866                         rcu_read_lock();
 867                         dev = dev_get_by_index_rcu(&init_net,
 868                                                    addr->v6.sin6_scope_id);
 869                         rcu_read_unlock();
 870                         if (!dev)
 871                                 return 0;
 872                 }
 873                 af = opt->pf->af;
 874         }
 875
 876         return af != NULL;
 877 }
 878
 879 /* Fill in Supported Address Type information for INIT and INIT-ACK
 880  * chunks.   Note: In the future, we may want to look at sock options
 881  * to determine whether a PF_INET6 socket really wants to have IPV4
 882  * addresses.
 883  * Returns number of addresses supported.
 884  */
 885 static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
 886                                       __be16 *types)
 887 {
 888         types[0] = SCTP_PARAM_IPV6_ADDRESS;
 889         if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) {
 890                 types[1] = SCTP_PARAM_IPV4_ADDRESS;
 891                 return 2;
 892         }
 893         return 1;
 894 }
 895
 896 static const struct proto_ops inet6_seqpacket_ops = {
 897         .family            = PF_INET6,
 898         .owner             = THIS_MODULE,
 899         .release           = inet6_release,
 900         .bind              = inet6_bind,
 901         .connect           = inet_dgram_connect,
 902         .socketpair        = sock_no_socketpair,
 903         .accept            = inet_accept,
 904         .getname           = inet6_getname,
 905         .poll              = sctp_poll,
 906         .ioctl             = inet6_ioctl,
 907         .listen            = sctp_inet_listen,
 908         .shutdown          = inet_shutdown,
 909         .setsockopt        = sock_common_setsockopt,
 910         .getsockopt        = sock_common_getsockopt,
 911         .sendmsg           = inet_sendmsg,
 912         .recvmsg           = sock_common_recvmsg,
 913         .mmap              = sock_no_mmap,
 914 #ifdef CONFIG_COMPAT
 915         .compat_setsockopt = compat_sock_common_setsockopt,
 916         .compat_getsockopt = compat_sock_common_getsockopt,
 917 #endif
 918 };
 919
 920 static struct inet_protosw sctpv6_seqpacket_protosw = {
 921         .type          = SOCK_SEQPACKET,
 922         .protocol      = IPPROTO_SCTP,
 923         .prot          = &sctpv6_prot,
 924         .ops           = &inet6_seqpacket_ops,
 925         .no_check      = 0,
 926         .flags         = SCTP_PROTOSW_FLAG
 927 };
 928 static struct inet_protosw sctpv6_stream_protosw = {
 929         .type          = SOCK_STREAM,
 930         .protocol      = IPPROTO_SCTP,
 931         .prot          = &sctpv6_prot,
 932         .ops           = &inet6_seqpacket_ops,
 933         .no_check      = 0,
 934         .flags         = SCTP_PROTOSW_FLAG,
 935 };
 936
 937 static int sctp6_rcv(struct sk_buff *skb)
 938 {
 939         return sctp_rcv(skb) ? -1 : 0;
 940 }
 941
 942 static const struct inet6_protocol sctpv6_protocol = {
 943         .handler      = sctp6_rcv,
 944         .err_handler  = sctp_v6_err,
 945         .flags        = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
 946 };
 947
 948 static struct sctp_af sctp_af_inet6 = {
 949         .sa_family         = AF_INET6,
 950         .sctp_xmit         = sctp_v6_xmit,
 951         .setsockopt        = ipv6_setsockopt,
 952         .getsockopt        = ipv6_getsockopt,
 953         .get_dst           = sctp_v6_get_dst,
 954         .get_saddr         = sctp_v6_get_saddr,
 955         .copy_addrlist     = sctp_v6_copy_addrlist,
 956         .from_skb          = sctp_v6_from_skb,
 957         .from_sk           = sctp_v6_from_sk,
 958         .to_sk_saddr       = sctp_v6_to_sk_saddr,
 959         .to_sk_daddr       = sctp_v6_to_sk_daddr,
 960         .from_addr_param   = sctp_v6_from_addr_param,
 961         .to_addr_param     = sctp_v6_to_addr_param,
 962         .dst_saddr         = sctp_v6_dst_saddr,
 963         .cmp_addr          = sctp_v6_cmp_addr,
 964         .scope             = sctp_v6_scope,
 965         .addr_valid        = sctp_v6_addr_valid,
 966         .inaddr_any        = sctp_v6_inaddr_any,
 967         .is_any            = sctp_v6_is_any,
 968         .available         = sctp_v6_available,
 969         .skb_iif           = sctp_v6_skb_iif,
 970         .is_ce             = sctp_v6_is_ce,
 971         .seq_dump_addr     = sctp_v6_seq_dump_addr,
 972         .ecn_capable       = sctp_v6_ecn_capable,
 973         .net_header_len    = sizeof(struct ipv6hdr),
 974         .sockaddr_len      = sizeof(struct sockaddr_in6),
 975 #ifdef CONFIG_COMPAT
 976         .compat_setsockopt = compat_ipv6_setsockopt,
 977         .compat_getsockopt = compat_ipv6_getsockopt,
 978 #endif
 979 };
 980
 981 static struct sctp_pf sctp_pf_inet6 = {
 982         .event_msgname = sctp_inet6_event_msgname,
 983         .skb_msgname   = sctp_inet6_skb_msgname,
 984         .af_supported  = sctp_inet6_af_supported,
 985         .cmp_addr      = sctp_inet6_cmp_addr,
 986         .bind_verify   = sctp_inet6_bind_verify,
 987         .send_verify   = sctp_inet6_send_verify,
 988         .supported_addrs = sctp_inet6_supported_addrs,
 989         .create_accept_sk = sctp_v6_create_accept_sk,
 990         .addr_v4map    = sctp_v6_addr_v4map,
 991         .af            = &sctp_af_inet6,
 992 };
 993
 994 /* Initialize IPv6 support and register with socket layer.  */
 995 void sctp_v6_pf_init(void)
 996 {
 997         /* Register the SCTP specific PF_INET6 functions. */
 998         sctp_register_pf(&sctp_pf_inet6, PF_INET6);
 999
1000         /* Register the SCTP specific AF_INET6 functions. */
1001         sctp_register_af(&sctp_af_inet6);
1002 }
1003
1004 void sctp_v6_pf_exit(void)
1005 {
1006         list_del(&sctp_af_inet6.list);
1007 }
1008
1009 /* Initialize IPv6 support and register with socket layer.  */
1010 int sctp_v6_protosw_init(void)
1011 {
1012         int rc;
1013
1014         rc = proto_register(&sctpv6_prot, 1);
1015         if (rc)
1016                 return rc;
1017
1018         /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
1019         inet6_register_protosw(&sctpv6_seqpacket_protosw);
1020         inet6_register_protosw(&sctpv6_stream_protosw);
1021
1022         return 0;
1023 }
1024
1025 void sctp_v6_protosw_exit(void)
1026 {
1027         inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
1028         inet6_unregister_protosw(&sctpv6_stream_protosw);
1029         proto_unregister(&sctpv6_prot);
1030 }
1031
1032
1033 /* Register with inet6 layer. */
1034 int sctp_v6_add_protocol(void)
1035 {
1036         /* Register notifier for inet6 address additions/deletions. */
1037         register_inet6addr_notifier(&sctp_inet6addr_notifier);
1038
1039         if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
1040                 return -EAGAIN;
1041
1042         return 0;
1043 }
1044
1045 /* Unregister with inet6 layer. */
1046 void sctp_v6_del_protocol(void)
1047 {
1048         inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
1049         unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1050 }