Pileus Git - ~andy/linux/blob - 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 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
  84                                          union sctp_addr *s2);
  85 static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr,
  86                               __be16 port);
  87 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
  88                             const union sctp_addr *addr2);
  89
  90 /* Event handler for inet6 address addition/deletion events.
  91  * The sctp_local_addr_list needs to be protocted by a spin lock since
  92  * multiple notifiers (say IPv4 and IPv6) may be running at the same
  93  * time and thus corrupt the list.
  94  * The reader side is protected with RCU.
  95  */
  96 static int sctp_inet6addr_event(struct notifier_block *this, unsigned long ev,
  97                                 void *ptr)
  98 {
  99         struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
 100         struct sctp_sockaddr_entry *addr = NULL;
 101         struct sctp_sockaddr_entry *temp;
 102         int found = 0;
 103
 104         switch (ev) {
 105         case NETDEV_UP:
 106                 addr = kmalloc(sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC);
 107                 if (addr) {
 108                         addr->a.v6.sin6_family = AF_INET6;
 109                         addr->a.v6.sin6_port = 0;
 110                         ipv6_addr_copy(&addr->a.v6.sin6_addr, &ifa->addr);
 111                         addr->a.v6.sin6_scope_id = ifa->idev->dev->ifindex;
 112                         addr->valid = 1;
 113                         spin_lock_bh(&sctp_local_addr_lock);
 114                         list_add_tail_rcu(&addr->list, &sctp_local_addr_list);
 115                         spin_unlock_bh(&sctp_local_addr_lock);
 116                 }
 117                 break;
 118         case NETDEV_DOWN:
 119                 spin_lock_bh(&sctp_local_addr_lock);
 120                 list_for_each_entry_safe(addr, temp,
 121                                         &sctp_local_addr_list, list) {
 122                         if (addr->a.sa.sa_family == AF_INET6 &&
 123                                         ipv6_addr_equal(&addr->a.v6.sin6_addr,
 124                                                 &ifa->addr)) {
 125                                 found = 1;
 126                                 addr->valid = 0;
 127                                 list_del_rcu(&addr->list);
 128                                 break;
 129                         }
 130                 }
 131                 spin_unlock_bh(&sctp_local_addr_lock);
 132                 if (found)
 133                         call_rcu(&addr->rcu, sctp_local_addr_free);
 134                 break;
 135         }
 136
 137         return NOTIFY_DONE;
 138 }
 139
 140 static struct notifier_block sctp_inet6addr_notifier = {
 141         .notifier_call = sctp_inet6addr_event,
 142 };
 143
 144 /* ICMP error handler. */
 145 SCTP_STATIC void sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 146                              u8 type, u8 code, int offset, __be32 info)
 147 {
 148         struct inet6_dev *idev;
 149         struct sock *sk;
 150         struct sctp_association *asoc;
 151         struct sctp_transport *transport;
 152         struct ipv6_pinfo *np;
 153         sk_buff_data_t saveip, savesctp;
 154         int err;
 155
 156         idev = in6_dev_get(skb->dev);
 157
 158         /* Fix up skb to look at the embedded net header. */
 159         saveip   = skb->network_header;
 160         savesctp = skb->transport_header;
 161         skb_reset_network_header(skb);
 162         skb_set_transport_header(skb, offset);
 163         sk = sctp_err_lookup(AF_INET6, skb, sctp_hdr(skb), &asoc, &transport);
 164         /* Put back, the original pointers. */
 165         skb->network_header   = saveip;
 166         skb->transport_header = savesctp;
 167         if (!sk) {
 168                 ICMP6_INC_STATS_BH(dev_net(skb->dev), idev, ICMP6_MIB_INERRORS);
 169                 goto out;
 170         }
 171
 172         /* Warning:  The sock lock is held.  Remember to call
 173          * sctp_err_finish!
 174          */
 175
 176         switch (type) {
 177         case ICMPV6_PKT_TOOBIG:
 178                 sctp_icmp_frag_needed(sk, asoc, transport, ntohl(info));
 179                 goto out_unlock;
 180         case ICMPV6_PARAMPROB:
 181                 if (ICMPV6_UNK_NEXTHDR == code) {
 182                         sctp_icmp_proto_unreachable(sk, asoc, transport);
 183                         goto out_unlock;
 184                 }
 185                 break;
 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, asoc);
 201 out:
 202         if (likely(idev != NULL))
 203                 in6_dev_put(idev);
 204 }
 205
 206 /* Based on tcp_v6_xmit() in tcp_ipv6.c. */
 207 static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *transport)
 208 {
 209         struct sock *sk = skb->sk;
 210         struct ipv6_pinfo *np = inet6_sk(sk);
 211         struct flowi6 fl6;
 212
 213         memset(&fl6, 0, sizeof(fl6));
 214
 215         fl6.flowi6_proto = sk->sk_protocol;
 216
 217         /* Fill in the dest address from the route entry passed with the skb
 218          * and the source address from the transport.
 219          */
 220         ipv6_addr_copy(&fl6.daddr, &transport->ipaddr.v6.sin6_addr);
 221         ipv6_addr_copy(&fl6.saddr, &transport->saddr.v6.sin6_addr);
 222
 223         fl6.flowlabel = np->flow_label;
 224         IP6_ECN_flow_xmit(sk, fl6.flowlabel);
 225         if (ipv6_addr_type(&fl6.saddr) & IPV6_ADDR_LINKLOCAL)
 226                 fl6.flowi6_oif = transport->saddr.v6.sin6_scope_id;
 227         else
 228                 fl6.flowi6_oif = sk->sk_bound_dev_if;
 229
 230         if (np->opt && np->opt->srcrt) {
 231                 struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
 232                 ipv6_addr_copy(&fl6.daddr, rt0->addr);
 233         }
 234
 235         SCTP_DEBUG_PRINTK("%s: skb:%p, len:%d, src:%pI6 dst:%pI6\n",
 236                           __func__, skb, skb->len,
 237                           &fl6.saddr, &fl6.daddr);
 238
 239         SCTP_INC_STATS(SCTP_MIB_OUTSCTPPACKS);
 240
 241         if (!(transport->param_flags & SPP_PMTUD_ENABLE))
 242                 skb->local_df = 1;
 243
 244         return ip6_xmit(sk, skb, &fl6, np->opt);
 245 }
 246
 247 /* Returns the dst cache entry for the given source and destination ip
 248  * addresses.
 249  */
 250 static struct dst_entry *sctp_v6_get_dst(struct sctp_association *asoc,
 251                                          union sctp_addr *daddr,
 252                                          union sctp_addr *saddr,
 253                                          struct flowi *fl,
 254                                          struct sock *sk)
 255 {
 256         struct dst_entry *dst = NULL;
 257         struct flowi6 *fl6 = &fl->u.ip6;
 258         struct sctp_bind_addr *bp;
 259         struct sctp_sockaddr_entry *laddr;
 260         union sctp_addr *baddr = NULL;
 261         union sctp_addr dst_saddr;
 262         __u8 matchlen = 0;
 263         __u8 bmatchlen;
 264         sctp_scope_t scope;
 265         int err = 0;
 266
 267         memset(fl6, 0, sizeof(struct flowi6));
 268         ipv6_addr_copy(&fl6->daddr, &daddr->v6.sin6_addr);
 269         if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
 270                 fl6->flowi6_oif = daddr->v6.sin6_scope_id;
 271
 272
 273         SCTP_DEBUG_PRINTK("%s: DST=%pI6 ", __func__, &fl6->daddr);
 274
 275         if (saddr) {
 276                 ipv6_addr_copy(&fl6->saddr, &saddr->v6.sin6_addr);
 277                 SCTP_DEBUG_PRINTK("SRC=%pI6 - ", &fl6->saddr);
 278         }
 279
 280         err = ip6_dst_lookup(sk, &dst, fl6);
 281         if (!asoc || saddr)
 282                 goto out;
 283
 284         bp = &asoc->base.bind_addr;
 285         scope = sctp_scope(daddr);
 286         /* ip6_dst_lookup has filled in the fl6->saddr for us.  Check
 287          * to see if we can use it.
 288          */
 289         if (!err) {
 290                 /* Walk through the bind address list and look for a bind
 291                  * address that matches the source address of the returned dst.
 292                  */
 293                 sctp_v6_to_addr(&dst_saddr, &fl6->saddr, htons(bp->port));
 294                 rcu_read_lock();
 295                 list_for_each_entry_rcu(laddr, &bp->address_list, list) {
 296                         if (!laddr->valid || (laddr->state != SCTP_ADDR_SRC))
 297                                 continue;
 298
 299                         /* Do not compare against v4 addrs */
 300                         if ((laddr->a.sa.sa_family == AF_INET6) &&
 301                             (sctp_v6_cmp_addr(&dst_saddr, &laddr->a))) {
 302                                 rcu_read_unlock();
 303                                 goto out;
 304                         }
 305                 }
 306                 rcu_read_unlock();
 307                 /* None of the bound addresses match the source address of the
 308                  * dst. So release it.
 309                  */
 310                 dst_release(dst);
 311                 dst = NULL;
 312         }
 313
 314         /* Walk through the bind address list and try to get the
 315          * best source address for a given destination.
 316          */
 317         rcu_read_lock();
 318         list_for_each_entry_rcu(laddr, &bp->address_list, list) {
 319                 if (!laddr->valid && laddr->state != SCTP_ADDR_SRC)
 320                         continue;
 321                 if ((laddr->a.sa.sa_family == AF_INET6) &&
 322                     (scope <= sctp_scope(&laddr->a))) {
 323                         bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
 324                         if (!baddr || (matchlen < bmatchlen)) {
 325                                 baddr = &laddr->a;
 326                                 matchlen = bmatchlen;
 327                         }
 328                 }
 329         }
 330         rcu_read_unlock();
 331         if (baddr) {
 332                 ipv6_addr_copy(&fl6->saddr, &baddr->v6.sin6_addr);
 333                 err = ip6_dst_lookup(sk, &dst, fl6);
 334         }
 335
 336 out:
 337         if (!err) {
 338                 struct rt6_info *rt;
 339                 rt = (struct rt6_info *)dst;
 340                 SCTP_DEBUG_PRINTK("rt6_dst:%pI6 rt6_src:%pI6\n",
 341                         &rt->rt6i_dst.addr, &fl6->saddr);
 342                 return dst;
 343         }
 344         SCTP_DEBUG_PRINTK("NO ROUTE\n");
 345         return NULL;
 346 }
 347
 348 /* Returns the number of consecutive initial bits that match in the 2 ipv6
 349  * addresses.
 350  */
 351 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
 352                                          union sctp_addr *s2)
 353 {
 354         return ipv6_addr_diff(&s1->v6.sin6_addr, &s2->v6.sin6_addr);
 355 }
 356
 357 /* Fills in the source address(saddr) based on the destination address(daddr)
 358  * and asoc's bind address list.
 359  */
 360 static void sctp_v6_get_saddr(struct sctp_sock *sk,
 361                               struct sctp_transport *t,
 362                               union sctp_addr *daddr,
 363                               struct flowi *fl)
 364 {
 365         struct flowi6 *fl6 = &fl->u.ip6;
 366         union sctp_addr *saddr = &t->saddr;
 367
 368         SCTP_DEBUG_PRINTK("%s: asoc:%p dst:%p daddr:%pI6 ",
 369                           __func__, t->asoc, t->dst, &daddr->v6.sin6_addr);
 370
 371
 372         if (t->dst) {
 373                 saddr->v6.sin6_family = AF_INET6;
 374                 ipv6_addr_copy(&saddr->v6.sin6_addr, &fl6->saddr);
 375         }
 376 }
 377
 378 /* Make a copy of all potential local addresses. */
 379 static void sctp_v6_copy_addrlist(struct list_head *addrlist,
 380                                   struct net_device *dev)
 381 {
 382         struct inet6_dev *in6_dev;
 383         struct inet6_ifaddr *ifp;
 384         struct sctp_sockaddr_entry *addr;
 385
 386         rcu_read_lock();
 387         if ((in6_dev = __in6_dev_get(dev)) == NULL) {
 388                 rcu_read_unlock();
 389                 return;
 390         }
 391
 392         read_lock_bh(&in6_dev->lock);
 393         list_for_each_entry(ifp, &in6_dev->addr_list, if_list) {
 394                 /* Add the address to the local list.  */
 395                 addr = t_new(struct sctp_sockaddr_entry, GFP_ATOMIC);
 396                 if (addr) {
 397                         addr->a.v6.sin6_family = AF_INET6;
 398                         addr->a.v6.sin6_port = 0;
 399                         ipv6_addr_copy(&addr->a.v6.sin6_addr, &ifp->addr);
 400                         addr->a.v6.sin6_scope_id = dev->ifindex;
 401                         addr->valid = 1;
 402                         INIT_LIST_HEAD(&addr->list);
 403                         list_add_tail(&addr->list, addrlist);
 404                 }
 405         }
 406
 407         read_unlock_bh(&in6_dev->lock);
 408         rcu_read_unlock();
 409 }
 410
 411 /* Initialize a sockaddr_storage from in incoming skb. */
 412 static void sctp_v6_from_skb(union sctp_addr *addr,struct sk_buff *skb,
 413                              int is_saddr)
 414 {
 415         void *from;
 416         __be16 *port;
 417         struct sctphdr *sh;
 418
 419         port = &addr->v6.sin6_port;
 420         addr->v6.sin6_family = AF_INET6;
 421         addr->v6.sin6_flowinfo = 0; /* FIXME */
 422         addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif;
 423
 424         sh = sctp_hdr(skb);
 425         if (is_saddr) {
 426                 *port  = sh->source;
 427                 from = &ipv6_hdr(skb)->saddr;
 428         } else {
 429                 *port = sh->dest;
 430                 from = &ipv6_hdr(skb)->daddr;
 431         }
 432         ipv6_addr_copy(&addr->v6.sin6_addr, from);
 433 }
 434
 435 /* Initialize an sctp_addr from a socket. */
 436 static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
 437 {
 438         addr->v6.sin6_family = AF_INET6;
 439         addr->v6.sin6_port = 0;
 440         ipv6_addr_copy(&addr->v6.sin6_addr, &inet6_sk(sk)->rcv_saddr);
 441 }
 442
 443 /* Initialize sk->sk_rcv_saddr from sctp_addr. */
 444 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
 445 {
 446         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
 447                 inet6_sk(sk)->rcv_saddr.s6_addr32[0] = 0;
 448                 inet6_sk(sk)->rcv_saddr.s6_addr32[1] = 0;
 449                 inet6_sk(sk)->rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
 450                 inet6_sk(sk)->rcv_saddr.s6_addr32[3] =
 451                         addr->v4.sin_addr.s_addr;
 452         } else {
 453                 ipv6_addr_copy(&inet6_sk(sk)->rcv_saddr, &addr->v6.sin6_addr);
 454         }
 455 }
 456
 457 /* Initialize sk->sk_daddr from sctp_addr. */
 458 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
 459 {
 460         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
 461                 inet6_sk(sk)->daddr.s6_addr32[0] = 0;
 462                 inet6_sk(sk)->daddr.s6_addr32[1] = 0;
 463                 inet6_sk(sk)->daddr.s6_addr32[2] = htonl(0x0000ffff);
 464                 inet6_sk(sk)->daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
 465         } else {
 466                 ipv6_addr_copy(&inet6_sk(sk)->daddr, &addr->v6.sin6_addr);
 467         }
 468 }
 469
 470 /* Initialize a sctp_addr from an address parameter. */
 471 static void sctp_v6_from_addr_param(union sctp_addr *addr,
 472                                     union sctp_addr_param *param,
 473                                     __be16 port, int iif)
 474 {
 475         addr->v6.sin6_family = AF_INET6;
 476         addr->v6.sin6_port = port;
 477         addr->v6.sin6_flowinfo = 0; /* BUG */
 478         ipv6_addr_copy(&addr->v6.sin6_addr, &param->v6.addr);
 479         addr->v6.sin6_scope_id = iif;
 480 }
 481
 482 /* Initialize an address parameter from a sctp_addr and return the length
 483  * of the address parameter.
 484  */
 485 static int sctp_v6_to_addr_param(const union sctp_addr *addr,
 486                                  union sctp_addr_param *param)
 487 {
 488         int length = sizeof(sctp_ipv6addr_param_t);
 489
 490         param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
 491         param->v6.param_hdr.length = htons(length);
 492         ipv6_addr_copy(&param->v6.addr, &addr->v6.sin6_addr);
 493
 494         return length;
 495 }
 496
 497 /* Initialize a sctp_addr from struct in6_addr. */
 498 static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr,
 499                               __be16 port)
 500 {
 501         addr->sa.sa_family = AF_INET6;
 502         addr->v6.sin6_port = port;
 503         ipv6_addr_copy(&addr->v6.sin6_addr, saddr);
 504 }
 505
 506 /* Compare addresses exactly.
 507  * v4-mapped-v6 is also in consideration.
 508  */
 509 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
 510                             const union sctp_addr *addr2)
 511 {
 512         if (addr1->sa.sa_family != addr2->sa.sa_family) {
 513                 if (addr1->sa.sa_family == AF_INET &&
 514                     addr2->sa.sa_family == AF_INET6 &&
 515                     ipv6_addr_v4mapped(&addr2->v6.sin6_addr)) {
 516                         if (addr2->v6.sin6_port == addr1->v4.sin_port &&
 517                             addr2->v6.sin6_addr.s6_addr32[3] ==
 518                             addr1->v4.sin_addr.s_addr)
 519                                 return 1;
 520                 }
 521                 if (addr2->sa.sa_family == AF_INET &&
 522                     addr1->sa.sa_family == AF_INET6 &&
 523                     ipv6_addr_v4mapped(&addr1->v6.sin6_addr)) {
 524                         if (addr1->v6.sin6_port == addr2->v4.sin_port &&
 525                             addr1->v6.sin6_addr.s6_addr32[3] ==
 526                             addr2->v4.sin_addr.s_addr)
 527                                 return 1;
 528                 }
 529                 return 0;
 530         }
 531         if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
 532                 return 0;
 533         /* If this is a linklocal address, compare the scope_id. */
 534         if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) {
 535                 if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
 536                     (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) {
 537                         return 0;
 538                 }
 539         }
 540
 541         return 1;
 542 }
 543
 544 /* Initialize addr struct to INADDR_ANY. */
 545 static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port)
 546 {
 547         memset(addr, 0x00, sizeof(union sctp_addr));
 548         addr->v6.sin6_family = AF_INET6;
 549         addr->v6.sin6_port = port;
 550 }
 551
 552 /* Is this a wildcard address? */
 553 static int sctp_v6_is_any(const union sctp_addr *addr)
 554 {
 555         return ipv6_addr_any(&addr->v6.sin6_addr);
 556 }
 557
 558 /* Should this be available for binding?   */
 559 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
 560 {
 561         int type;
 562         const struct in6_addr *in6 = (const struct in6_addr *)&addr->v6.sin6_addr;
 563
 564         type = ipv6_addr_type(in6);
 565         if (IPV6_ADDR_ANY == type)
 566                 return 1;
 567         if (type == IPV6_ADDR_MAPPED) {
 568                 if (sp && !sp->v4mapped)
 569                         return 0;
 570                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
 571                         return 0;
 572                 sctp_v6_map_v4(addr);
 573                 return sctp_get_af_specific(AF_INET)->available(addr, sp);
 574         }
 575         if (!(type & IPV6_ADDR_UNICAST))
 576                 return 0;
 577
 578         return ipv6_chk_addr(&init_net, in6, NULL, 0);
 579 }
 580
 581 /* This function checks if the address is a valid address to be used for
 582  * SCTP.
 583  *
 584  * Output:
 585  * Return 0 - If the address is a non-unicast or an illegal address.
 586  * Return 1 - If the address is a unicast.
 587  */
 588 static int sctp_v6_addr_valid(union sctp_addr *addr,
 589                               struct sctp_sock *sp,
 590                               const struct sk_buff *skb)
 591 {
 592         int ret = ipv6_addr_type(&addr->v6.sin6_addr);
 593
 594         /* Support v4-mapped-v6 address. */
 595         if (ret == IPV6_ADDR_MAPPED) {
 596                 /* Note: This routine is used in input, so v4-mapped-v6
 597                  * are disallowed here when there is no sctp_sock.
 598                  */
 599                 if (!sp || !sp->v4mapped)
 600                         return 0;
 601                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
 602                         return 0;
 603                 sctp_v6_map_v4(addr);
 604                 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb);
 605         }
 606
 607         /* Is this a non-unicast address */
 608         if (!(ret & IPV6_ADDR_UNICAST))
 609                 return 0;
 610
 611         return 1;
 612 }
 613
 614 /* What is the scope of 'addr'?  */
 615 static sctp_scope_t sctp_v6_scope(union sctp_addr *addr)
 616 {
 617         int v6scope;
 618         sctp_scope_t retval;
 619
 620         /* The IPv6 scope is really a set of bit fields.
 621          * See IFA_* in <net/if_inet6.h>.  Map to a generic SCTP scope.
 622          */
 623
 624         v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
 625         switch (v6scope) {
 626         case IFA_HOST:
 627                 retval = SCTP_SCOPE_LOOPBACK;
 628                 break;
 629         case IFA_LINK:
 630                 retval = SCTP_SCOPE_LINK;
 631                 break;
 632         case IFA_SITE:
 633                 retval = SCTP_SCOPE_PRIVATE;
 634                 break;
 635         default:
 636                 retval = SCTP_SCOPE_GLOBAL;
 637                 break;
 638         }
 639
 640         return retval;
 641 }
 642
 643 /* Create and initialize a new sk for the socket to be returned by accept(). */
 644 static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
 645                                              struct sctp_association *asoc)
 646 {
 647         struct sock *newsk;
 648         struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
 649         struct sctp6_sock *newsctp6sk;
 650
 651         newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot);
 652         if (!newsk)
 653                 goto out;
 654
 655         sock_init_data(NULL, newsk);
 656
 657         sctp_copy_sock(newsk, sk, asoc);
 658         sock_reset_flag(sk, SOCK_ZAPPED);
 659
 660         newsctp6sk = (struct sctp6_sock *)newsk;
 661         inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
 662
 663         sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped;
 664
 665         newnp = inet6_sk(newsk);
 666
 667         memcpy(newnp, np, sizeof(struct ipv6_pinfo));
 668
 669         /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
 670          * and getpeername().
 671          */
 672         sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
 673
 674         sk_refcnt_debug_inc(newsk);
 675
 676         if (newsk->sk_prot->init(newsk)) {
 677                 sk_common_release(newsk);
 678                 newsk = NULL;
 679         }
 680
 681 out:
 682         return newsk;
 683 }
 684
 685 /* Map v4 address to mapped v6 address */
 686 static void sctp_v6_addr_v4map(struct sctp_sock *sp, union sctp_addr *addr)
 687 {
 688         if (sp->v4mapped && AF_INET == addr->sa.sa_family)
 689                 sctp_v4_map_v6(addr);
 690 }
 691
 692 /* Where did this skb come from?  */
 693 static int sctp_v6_skb_iif(const struct sk_buff *skb)
 694 {
 695         struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb;
 696         return opt->iif;
 697 }
 698
 699 /* Was this packet marked by Explicit Congestion Notification? */
 700 static int sctp_v6_is_ce(const struct sk_buff *skb)
 701 {
 702         return *((__u32 *)(ipv6_hdr(skb))) & htonl(1 << 20);
 703 }
 704
 705 /* Dump the v6 addr to the seq file. */
 706 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
 707 {
 708         seq_printf(seq, "%pI6 ", &addr->v6.sin6_addr);
 709 }
 710
 711 static void sctp_v6_ecn_capable(struct sock *sk)
 712 {
 713         inet6_sk(sk)->tclass |= INET_ECN_ECT_0;
 714 }
 715
 716 /* Initialize a PF_INET6 socket msg_name. */
 717 static void sctp_inet6_msgname(char *msgname, int *addr_len)
 718 {
 719         struct sockaddr_in6 *sin6;
 720
 721         sin6 = (struct sockaddr_in6 *)msgname;
 722         sin6->sin6_family = AF_INET6;
 723         sin6->sin6_flowinfo = 0;
 724         sin6->sin6_scope_id = 0; /*FIXME */
 725         *addr_len = sizeof(struct sockaddr_in6);
 726 }
 727
 728 /* Initialize a PF_INET msgname from a ulpevent. */
 729 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
 730                                      char *msgname, int *addrlen)
 731 {
 732         struct sockaddr_in6 *sin6, *sin6from;
 733
 734         if (msgname) {
 735                 union sctp_addr *addr;
 736                 struct sctp_association *asoc;
 737
 738                 asoc = event->asoc;
 739                 sctp_inet6_msgname(msgname, addrlen);
 740                 sin6 = (struct sockaddr_in6 *)msgname;
 741                 sin6->sin6_port = htons(asoc->peer.port);
 742                 addr = &asoc->peer.primary_addr;
 743
 744                 /* Note: If we go to a common v6 format, this code
 745                  * will change.
 746                  */
 747
 748                 /* Map ipv4 address into v4-mapped-on-v6 address.  */
 749                 if (sctp_sk(asoc->base.sk)->v4mapped &&
 750                     AF_INET == addr->sa.sa_family) {
 751                         sctp_v4_map_v6((union sctp_addr *)sin6);
 752                         sin6->sin6_addr.s6_addr32[3] =
 753                                 addr->v4.sin_addr.s_addr;
 754                         return;
 755                 }
 756
 757                 sin6from = &asoc->peer.primary_addr.v6;
 758                 ipv6_addr_copy(&sin6->sin6_addr, &sin6from->sin6_addr);
 759                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 760                         sin6->sin6_scope_id = sin6from->sin6_scope_id;
 761         }
 762 }
 763
 764 /* Initialize a msg_name from an inbound skb. */
 765 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
 766                                    int *addr_len)
 767 {
 768         struct sctphdr *sh;
 769         struct sockaddr_in6 *sin6;
 770
 771         if (msgname) {
 772                 sctp_inet6_msgname(msgname, addr_len);
 773                 sin6 = (struct sockaddr_in6 *)msgname;
 774                 sh = sctp_hdr(skb);
 775                 sin6->sin6_port = sh->source;
 776
 777                 /* Map ipv4 address into v4-mapped-on-v6 address. */
 778                 if (sctp_sk(skb->sk)->v4mapped &&
 779                     ip_hdr(skb)->version == 4) {
 780                         sctp_v4_map_v6((union sctp_addr *)sin6);
 781                         sin6->sin6_addr.s6_addr32[3] = ip_hdr(skb)->saddr;
 782                         return;
 783                 }
 784
 785                 /* Otherwise, just copy the v6 address. */
 786                 ipv6_addr_copy(&sin6->sin6_addr, &ipv6_hdr(skb)->saddr);
 787                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) {
 788                         struct sctp_ulpevent *ev = sctp_skb2event(skb);
 789                         sin6->sin6_scope_id = ev->iif;
 790                 }
 791         }
 792 }
 793
 794 /* Do we support this AF? */
 795 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
 796 {
 797         switch (family) {
 798         case AF_INET6:
 799                 return 1;
 800         /* v4-mapped-v6 addresses */
 801         case AF_INET:
 802                 if (!__ipv6_only_sock(sctp_opt2sk(sp)))
 803                         return 1;
 804         default:
 805                 return 0;
 806         }
 807 }
 808
 809 /* Address matching with wildcards allowed.  This extra level
 810  * of indirection lets us choose whether a PF_INET6 should
 811  * disallow any v4 addresses if we so choose.
 812  */
 813 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
 814                                const union sctp_addr *addr2,
 815                                struct sctp_sock *opt)
 816 {
 817         struct sctp_af *af1, *af2;
 818         struct sock *sk = sctp_opt2sk(opt);
 819
 820         af1 = sctp_get_af_specific(addr1->sa.sa_family);
 821         af2 = sctp_get_af_specific(addr2->sa.sa_family);
 822
 823         if (!af1 || !af2)
 824                 return 0;
 825
 826         /* If the socket is IPv6 only, v4 addrs will not match */
 827         if (__ipv6_only_sock(sk) && af1 != af2)
 828                 return 0;
 829
 830         /* Today, wildcard AF_INET/AF_INET6. */
 831         if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2))
 832                 return 1;
 833
 834         if (addr1->sa.sa_family != addr2->sa.sa_family)
 835                 return 0;
 836
 837         return af1->cmp_addr(addr1, addr2);
 838 }
 839
 840 /* Verify that the provided sockaddr looks bindable.   Common verification,
 841  * has already been taken care of.
 842  */
 843 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
 844 {
 845         struct sctp_af *af;
 846
 847         /* ASSERT: address family has already been verified. */
 848         if (addr->sa.sa_family != AF_INET6)
 849                 af = sctp_get_af_specific(addr->sa.sa_family);
 850         else {
 851                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
 852                 struct net_device *dev;
 853
 854                 if (type & IPV6_ADDR_LINKLOCAL) {
 855                         if (!addr->v6.sin6_scope_id)
 856                                 return 0;
 857                         rcu_read_lock();
 858                         dev = dev_get_by_index_rcu(&init_net,
 859                                                    addr->v6.sin6_scope_id);
 860                         if (!dev ||
 861                             !ipv6_chk_addr(&init_net, &addr->v6.sin6_addr,
 862                                            dev, 0)) {
 863                                 rcu_read_unlock();
 864                                 return 0;
 865                         }
 866                         rcu_read_unlock();
 867                 } else if (type == IPV6_ADDR_MAPPED) {
 868                         if (!opt->v4mapped)
 869                                 return 0;
 870                 }
 871
 872                 af = opt->pf->af;
 873         }
 874         return af->available(addr, opt);
 875 }
 876
 877 /* Verify that the provided sockaddr looks sendable.   Common verification,
 878  * has already been taken care of.
 879  */
 880 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
 881 {
 882         struct sctp_af *af = NULL;
 883
 884         /* ASSERT: address family has already been verified. */
 885         if (addr->sa.sa_family != AF_INET6)
 886                 af = sctp_get_af_specific(addr->sa.sa_family);
 887         else {
 888                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
 889                 struct net_device *dev;
 890
 891                 if (type & IPV6_ADDR_LINKLOCAL) {
 892                         if (!addr->v6.sin6_scope_id)
 893                                 return 0;
 894                         rcu_read_lock();
 895                         dev = dev_get_by_index_rcu(&init_net,
 896                                                    addr->v6.sin6_scope_id);
 897                         rcu_read_unlock();
 898                         if (!dev)
 899                                 return 0;
 900                 }
 901                 af = opt->pf->af;
 902         }
 903
 904         return af != NULL;
 905 }
 906
 907 /* Fill in Supported Address Type information for INIT and INIT-ACK
 908  * chunks.   Note: In the future, we may want to look at sock options
 909  * to determine whether a PF_INET6 socket really wants to have IPV4
 910  * addresses.
 911  * Returns number of addresses supported.
 912  */
 913 static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
 914                                       __be16 *types)
 915 {
 916         types[0] = SCTP_PARAM_IPV6_ADDRESS;
 917         if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) {
 918                 types[1] = SCTP_PARAM_IPV4_ADDRESS;
 919                 return 2;
 920         }
 921         return 1;
 922 }
 923
 924 static const struct proto_ops inet6_seqpacket_ops = {
 925         .family            = PF_INET6,
 926         .owner             = THIS_MODULE,
 927         .release           = inet6_release,
 928         .bind              = inet6_bind,
 929         .connect           = inet_dgram_connect,
 930         .socketpair        = sock_no_socketpair,
 931         .accept            = inet_accept,
 932         .getname           = inet6_getname,
 933         .poll              = sctp_poll,
 934         .ioctl             = inet6_ioctl,
 935         .listen            = sctp_inet_listen,
 936         .shutdown          = inet_shutdown,
 937         .setsockopt        = sock_common_setsockopt,
 938         .getsockopt        = sock_common_getsockopt,
 939         .sendmsg           = inet_sendmsg,
 940         .recvmsg           = sock_common_recvmsg,
 941         .mmap              = sock_no_mmap,
 942 #ifdef CONFIG_COMPAT
 943         .compat_setsockopt = compat_sock_common_setsockopt,
 944         .compat_getsockopt = compat_sock_common_getsockopt,
 945 #endif
 946 };
 947
 948 static struct inet_protosw sctpv6_seqpacket_protosw = {
 949         .type          = SOCK_SEQPACKET,
 950         .protocol      = IPPROTO_SCTP,
 951         .prot          = &sctpv6_prot,
 952         .ops           = &inet6_seqpacket_ops,
 953         .no_check      = 0,
 954         .flags         = SCTP_PROTOSW_FLAG
 955 };
 956 static struct inet_protosw sctpv6_stream_protosw = {
 957         .type          = SOCK_STREAM,
 958         .protocol      = IPPROTO_SCTP,
 959         .prot          = &sctpv6_prot,
 960         .ops           = &inet6_seqpacket_ops,
 961         .no_check      = 0,
 962         .flags         = SCTP_PROTOSW_FLAG,
 963 };
 964
 965 static int sctp6_rcv(struct sk_buff *skb)
 966 {
 967         return sctp_rcv(skb) ? -1 : 0;
 968 }
 969
 970 static const struct inet6_protocol sctpv6_protocol = {
 971         .handler      = sctp6_rcv,
 972         .err_handler  = sctp_v6_err,
 973         .flags        = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
 974 };
 975
 976 static struct sctp_af sctp_af_inet6 = {
 977         .sa_family         = AF_INET6,
 978         .sctp_xmit         = sctp_v6_xmit,
 979         .setsockopt        = ipv6_setsockopt,
 980         .getsockopt        = ipv6_getsockopt,
 981         .get_dst           = sctp_v6_get_dst,
 982         .get_saddr         = sctp_v6_get_saddr,
 983         .copy_addrlist     = sctp_v6_copy_addrlist,
 984         .from_skb          = sctp_v6_from_skb,
 985         .from_sk           = sctp_v6_from_sk,
 986         .to_sk_saddr       = sctp_v6_to_sk_saddr,
 987         .to_sk_daddr       = sctp_v6_to_sk_daddr,
 988         .from_addr_param   = sctp_v6_from_addr_param,
 989         .to_addr_param     = sctp_v6_to_addr_param,
 990         .cmp_addr          = sctp_v6_cmp_addr,
 991         .scope             = sctp_v6_scope,
 992         .addr_valid        = sctp_v6_addr_valid,
 993         .inaddr_any        = sctp_v6_inaddr_any,
 994         .is_any            = sctp_v6_is_any,
 995         .available         = sctp_v6_available,
 996         .skb_iif           = sctp_v6_skb_iif,
 997         .is_ce             = sctp_v6_is_ce,
 998         .seq_dump_addr     = sctp_v6_seq_dump_addr,
 999         .ecn_capable       = sctp_v6_ecn_capable,
1000         .net_header_len    = sizeof(struct ipv6hdr),
1001         .sockaddr_len      = sizeof(struct sockaddr_in6),
1002 #ifdef CONFIG_COMPAT
1003         .compat_setsockopt = compat_ipv6_setsockopt,
1004         .compat_getsockopt = compat_ipv6_getsockopt,
1005 #endif
1006 };
1007
1008 static struct sctp_pf sctp_pf_inet6 = {
1009         .event_msgname = sctp_inet6_event_msgname,
1010         .skb_msgname   = sctp_inet6_skb_msgname,
1011         .af_supported  = sctp_inet6_af_supported,
1012         .cmp_addr      = sctp_inet6_cmp_addr,
1013         .bind_verify   = sctp_inet6_bind_verify,
1014         .send_verify   = sctp_inet6_send_verify,
1015         .supported_addrs = sctp_inet6_supported_addrs,
1016         .create_accept_sk = sctp_v6_create_accept_sk,
1017         .addr_v4map    = sctp_v6_addr_v4map,
1018         .af            = &sctp_af_inet6,
1019 };
1020
1021 /* Initialize IPv6 support and register with socket layer.  */
1022 void sctp_v6_pf_init(void)
1023 {
1024         /* Register the SCTP specific PF_INET6 functions. */
1025         sctp_register_pf(&sctp_pf_inet6, PF_INET6);
1026
1027         /* Register the SCTP specific AF_INET6 functions. */
1028         sctp_register_af(&sctp_af_inet6);
1029 }
1030
1031 void sctp_v6_pf_exit(void)
1032 {
1033         list_del(&sctp_af_inet6.list);
1034 }
1035
1036 /* Initialize IPv6 support and register with socket layer.  */
1037 int sctp_v6_protosw_init(void)
1038 {
1039         int rc;
1040
1041         rc = proto_register(&sctpv6_prot, 1);
1042         if (rc)
1043                 return rc;
1044
1045         /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
1046         inet6_register_protosw(&sctpv6_seqpacket_protosw);
1047         inet6_register_protosw(&sctpv6_stream_protosw);
1048
1049         return 0;
1050 }
1051
1052 void sctp_v6_protosw_exit(void)
1053 {
1054         inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
1055         inet6_unregister_protosw(&sctpv6_stream_protosw);
1056         proto_unregister(&sctpv6_prot);
1057 }
1058
1059
1060 /* Register with inet6 layer. */
1061 int sctp_v6_add_protocol(void)
1062 {
1063         /* Register notifier for inet6 address additions/deletions. */
1064         register_inet6addr_notifier(&sctp_inet6addr_notifier);
1065
1066         if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
1067                 return -EAGAIN;
1068
1069         return 0;
1070 }
1071
1072 /* Unregister with inet6 layer. */
1073 void sctp_v6_del_protocol(void)
1074 {
1075         inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
1076         unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1077 }