net/sctp/ipv6.c

   1 /* SCTP kernel implementation
   2  * (C) Copyright IBM Corp. 2002, 2004
   3  * Copyright (c) 2001 Nokia, Inc.
   4  * Copyright (c) 2001 La Monte H.P. Yarroll
   5  * Copyright (c) 2002-2003 Intel Corp.
   6  *
   7  * This file is part of the SCTP kernel implementation
   8  *
   9  * SCTP over IPv6.
  10  *
  11  * This SCTP implementation is free software;
  12  * you can redistribute it and/or modify it under the terms of
  13  * the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2, or (at your option)
  15  * any later version.
  16  *
  17  * This SCTP implementation is distributed in the hope that it
  18  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
  19  *                 ************************
  20  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  21  * See the GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with GNU CC; see the file COPYING.  If not, see
  25  * <http://www.gnu.org/licenses/>.
  26  *
  27  * Please send any bug reports or fixes you make to the
  28  * email address(es):
  29  *    lksctp developers <linux-sctp@vger.kernel.org>
  30  *
  31  * Written or modified by:
  32  *    Le Yanqun             <yanqun.le@nokia.com>
  33  *    Hui Huang             <hui.huang@nokia.com>
  34  *    La Monte H.P. Yarroll <piggy@acm.org>
  35  *    Sridhar Samudrala     <sri@us.ibm.com>
  36  *    Jon Grimm             <jgrimm@us.ibm.com>
  37  *    Ardelle Fan           <ardelle.fan@intel.com>
  38  *
  39  * Based on:
  40  *      linux/net/ipv6/tcp_ipv6.c
  41  */
  42
  43 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  44
  45 #include <linux/module.h>
  46 #include <linux/errno.h>
  47 #include <linux/types.h>
  48 #include <linux/socket.h>
  49 #include <linux/sockios.h>
  50 #include <linux/net.h>
  51 #include <linux/in.h>
  52 #include <linux/in6.h>
  53 #include <linux/netdevice.h>
  54 #include <linux/init.h>
  55 #include <linux/ipsec.h>
  56 #include <linux/slab.h>
  57
  58 #include <linux/ipv6.h>
  59 #include <linux/icmpv6.h>
  60 #include <linux/random.h>
  61 #include <linux/seq_file.h>
  62
  63 #include <net/protocol.h>
  64 #include <net/ndisc.h>
  65 #include <net/ip.h>
  66 #include <net/ipv6.h>
  67 #include <net/transp_v6.h>
  68 #include <net/addrconf.h>
  69 #include <net/ip6_route.h>
  70 #include <net/inet_common.h>
  71 #include <net/inet_ecn.h>
  72 #include <net/sctp/sctp.h>
  73
  74 #include <asm/uaccess.h>
  75
  76 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
  77                                          union sctp_addr *s2);
  78 static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr,
  79                               __be16 port);
  80 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
  81                             const union sctp_addr *addr2);
  82
  83 /* Event handler for inet6 address addition/deletion events.
  84  * The sctp_local_addr_list needs to be protocted by a spin lock since
  85  * multiple notifiers (say IPv4 and IPv6) may be running at the same
  86  * time and thus corrupt the list.
  87  * The reader side is protected with RCU.
  88  */
  89 static int sctp_inet6addr_event(struct notifier_block *this, unsigned long ev,
  90                                 void *ptr)
  91 {
  92         struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
  93         struct sctp_sockaddr_entry *addr = NULL;
  94         struct sctp_sockaddr_entry *temp;
  95         struct net *net = dev_net(ifa->idev->dev);
  96         int found = 0;
  97
  98         switch (ev) {
  99         case NETDEV_UP:
 100                 addr = kzalloc(sizeof(*addr), GFP_ATOMIC);
 101                 if (addr) {
 102                         addr->a.v6.sin6_family = AF_INET6;
 103                         addr->a.v6.sin6_addr = ifa->addr;
 104                         addr->a.v6.sin6_scope_id = ifa->idev->dev->ifindex;
 105                         addr->valid = 1;
 106                         spin_lock_bh(&net->sctp.local_addr_lock);
 107                         list_add_tail_rcu(&addr->list, &net->sctp.local_addr_list);
 108                         sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_NEW);
 109                         spin_unlock_bh(&net->sctp.local_addr_lock);
 110                 }
 111                 break;
 112         case NETDEV_DOWN:
 113                 spin_lock_bh(&net->sctp.local_addr_lock);
 114                 list_for_each_entry_safe(addr, temp,
 115                                         &net->sctp.local_addr_list, list) {
 116                         if (addr->a.sa.sa_family == AF_INET6 &&
 117                                         ipv6_addr_equal(&addr->a.v6.sin6_addr,
 118                                                 &ifa->addr)) {
 119                                 sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_DEL);
 120                                 found = 1;
 121                                 addr->valid = 0;
 122                                 list_del_rcu(&addr->list);
 123                                 break;
 124                         }
 125                 }
 126                 spin_unlock_bh(&net->sctp.local_addr_lock);
 127                 if (found)
 128                         kfree_rcu(addr, rcu);
 129                 break;
 130         }
 131
 132         return NOTIFY_DONE;
 133 }
 134
 135 static struct notifier_block sctp_inet6addr_notifier = {
 136         .notifier_call = sctp_inet6addr_event,
 137 };
 138
 139 /* ICMP error handler. */
 140 static void sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 141                         u8 type, u8 code, int offset, __be32 info)
 142 {
 143         struct inet6_dev *idev;
 144         struct sock *sk;
 145         struct sctp_association *asoc;
 146         struct sctp_transport *transport;
 147         struct ipv6_pinfo *np;
 148         __u16 saveip, savesctp;
 149         int err;
 150         struct net *net = dev_net(skb->dev);
 151
 152         idev = in6_dev_get(skb->dev);
 153
 154         /* Fix up skb to look at the embedded net header. */
 155         saveip   = skb->network_header;
 156         savesctp = skb->transport_header;
 157         skb_reset_network_header(skb);
 158         skb_set_transport_header(skb, offset);
 159         sk = sctp_err_lookup(net, AF_INET6, skb, sctp_hdr(skb), &asoc, &transport);
 160         /* Put back, the original pointers. */
 161         skb->network_header   = saveip;
 162         skb->transport_header = savesctp;
 163         if (!sk) {
 164                 ICMP6_INC_STATS_BH(net, idev, ICMP6_MIB_INERRORS);
 165                 goto out;
 166         }
 167
 168         /* Warning:  The sock lock is held.  Remember to call
 169          * sctp_err_finish!
 170          */
 171
 172         switch (type) {
 173         case ICMPV6_PKT_TOOBIG:
 174                 if (ip6_sk_accept_pmtu(sk))
 175                         sctp_icmp_frag_needed(sk, asoc, transport, ntohl(info));
 176                 goto out_unlock;
 177         case ICMPV6_PARAMPROB:
 178                 if (ICMPV6_UNK_NEXTHDR == code) {
 179                         sctp_icmp_proto_unreachable(sk, asoc, transport);
 180                         goto out_unlock;
 181                 }
 182                 break;
 183         case NDISC_REDIRECT:
 184                 sctp_icmp_redirect(sk, transport, skb);
 185                 goto out_unlock;
 186         default:
 187                 break;
 188         }
 189
 190         np = inet6_sk(sk);
 191         icmpv6_err_convert(type, code, &err);
 192         if (!sock_owned_by_user(sk) && np->recverr) {
 193                 sk->sk_err = err;
 194                 sk->sk_error_report(sk);
 195         } else {  /* Only an error on timeout */
 196                 sk->sk_err_soft = err;
 197         }
 198
 199 out_unlock:
 200         sctp_err_finish(sk, asoc);
 201 out:
 202         if (likely(idev != NULL))
 203                 in6_dev_put(idev);
 204 }
 205
 206 static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *transport)
 207 {
 208         struct sock *sk = skb->sk;
 209         struct ipv6_pinfo *np = inet6_sk(sk);
 210         struct flowi6 *fl6 = &transport->fl.u.ip6;
 211         int res;
 212
 213         pr_debug("%s: skb:%p, len:%d, src:%pI6 dst:%pI6\n", __func__, skb,
 214                  skb->len, &fl6->saddr, &fl6->daddr);
 215
 216         IP6_ECN_flow_xmit(sk, fl6->flowlabel);
 217
 218         if (!(transport->param_flags & SPP_PMTUD_ENABLE))
 219                 skb->ignore_df = 1;
 220
 221         SCTP_INC_STATS(sock_net(sk), SCTP_MIB_OUTSCTPPACKS);
 222
 223         rcu_read_lock();
 224         res = ip6_xmit(sk, skb, fl6, rcu_dereference(np->opt), np->tclass);
 225         rcu_read_unlock();
 226         return res;
 227 }
 228
 229 /* Returns the dst cache entry for the given source and destination ip
 230  * addresses.
 231  */
 232 static void sctp_v6_get_dst(struct sctp_transport *t, union sctp_addr *saddr,
 233                             struct flowi *fl, struct sock *sk)
 234 {
 235         struct sctp_association *asoc = t->asoc;
 236         struct dst_entry *dst = NULL;
 237         struct flowi _fl;
 238         struct flowi6 *fl6 = &_fl.u.ip6;
 239         struct sctp_bind_addr *bp;
 240         struct ipv6_pinfo *np = inet6_sk(sk);
 241         struct sctp_sockaddr_entry *laddr;
 242         union sctp_addr *daddr = &t->ipaddr;
 243         union sctp_addr dst_saddr;
 244         struct in6_addr *final_p, final;
 245         __u8 matchlen = 0;
 246         sctp_scope_t scope;
 247
 248         memset(&_fl, 0, sizeof(_fl));
 249         fl6->daddr = daddr->v6.sin6_addr;
 250         fl6->fl6_dport = daddr->v6.sin6_port;
 251         fl6->flowi6_proto = IPPROTO_SCTP;
 252         if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
 253                 fl6->flowi6_oif = daddr->v6.sin6_scope_id;
 254
 255         pr_debug("%s: dst=%pI6 ", __func__, &fl6->daddr);
 256
 257         if (asoc)
 258                 fl6->fl6_sport = htons(asoc->base.bind_addr.port);
 259
 260         if (saddr) {
 261                 fl6->saddr = saddr->v6.sin6_addr;
 262                 fl6->fl6_sport = saddr->v6.sin6_port;
 263
 264                 pr_debug("src=%pI6 - ", &fl6->saddr);
 265         }
 266
 267         rcu_read_lock();
 268         final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final);
 269         rcu_read_unlock();
 270
 271         dst = ip6_dst_lookup_flow(sock_net(sk), sk, fl6, final_p);
 272         if (!asoc || saddr) {
 273                 t->dst = dst;
 274                 memcpy(fl, &_fl, sizeof(_fl));
 275                 goto out;
 276         }
 277
 278         bp = &asoc->base.bind_addr;
 279         scope = sctp_scope(daddr);
 280         /* ip6_dst_lookup has filled in the fl6->saddr for us.  Check
 281          * to see if we can use it.
 282          */
 283         if (!IS_ERR(dst)) {
 284                 /* Walk through the bind address list and look for a bind
 285                  * address that matches the source address of the returned dst.
 286                  */
 287                 sctp_v6_to_addr(&dst_saddr, &fl6->saddr, htons(bp->port));
 288                 rcu_read_lock();
 289                 list_for_each_entry_rcu(laddr, &bp->address_list, list) {
 290                         if (!laddr->valid || laddr->state == SCTP_ADDR_DEL ||
 291                             (laddr->state != SCTP_ADDR_SRC &&
 292                              !asoc->src_out_of_asoc_ok))
 293                                 continue;
 294
 295                         /* Do not compare against v4 addrs */
 296                         if ((laddr->a.sa.sa_family == AF_INET6) &&
 297                             (sctp_v6_cmp_addr(&dst_saddr, &laddr->a))) {
 298                                 rcu_read_unlock();
 299                                 t->dst = dst;
 300                                 memcpy(fl, &_fl, sizeof(_fl));
 301                                 goto out;
 302                         }
 303                 }
 304                 rcu_read_unlock();
 305                 /* None of the bound addresses match the source address of the
 306                  * dst. So release it.
 307                  */
 308                 dst_release(dst);
 309                 dst = NULL;
 310         }
 311
 312         /* Walk through the bind address list and try to get the
 313          * best source address for a given destination.
 314          */
 315         rcu_read_lock();
 316         list_for_each_entry_rcu(laddr, &bp->address_list, list) {
 317                 struct dst_entry *bdst;
 318                 __u8 bmatchlen;
 319
 320                 if (!laddr->valid ||
 321                     laddr->state != SCTP_ADDR_SRC ||
 322                     laddr->a.sa.sa_family != AF_INET6 ||
 323                     scope > sctp_scope(&laddr->a))
 324                         continue;
 325
 326                 fl6->saddr = laddr->a.v6.sin6_addr;
 327                 fl6->fl6_sport = laddr->a.v6.sin6_port;
 328                 final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final);
 329                 bdst = ip6_dst_lookup_flow(sock_net(sk), sk, fl6, final_p);
 330
 331                 if (IS_ERR(bdst))
 332                         continue;
 333
 334                 if (ipv6_chk_addr(dev_net(bdst->dev),
 335                                   &laddr->a.v6.sin6_addr, bdst->dev, 1)) {
 336                         if (!IS_ERR_OR_NULL(dst))
 337                                 dst_release(dst);
 338                         dst = bdst;
 339                         t->dst = dst;
 340                         memcpy(fl, &_fl, sizeof(_fl));
 341                         break;
 342                 }
 343
 344                 bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
 345                 if (matchlen > bmatchlen) {
 346                         dst_release(bdst);
 347                         continue;
 348                 }
 349
 350                 if (!IS_ERR_OR_NULL(dst))
 351                         dst_release(dst);
 352                 dst = bdst;
 353                 matchlen = bmatchlen;
 354                 t->dst = dst;
 355                 memcpy(fl, &_fl, sizeof(_fl));
 356         }
 357         rcu_read_unlock();
 358
 359 out:
 360         if (!IS_ERR_OR_NULL(dst)) {
 361                 struct rt6_info *rt;
 362
 363                 rt = (struct rt6_info *)dst;
 364                 t->dst_cookie = rt6_get_cookie(rt);
 365                 pr_debug("rt6_dst:%pI6/%d rt6_src:%pI6\n",
 366                          &rt->rt6i_dst.addr, rt->rt6i_dst.plen,
 367                          &fl->u.ip6.saddr);
 368         } else {
 369                 t->dst = NULL;
 370                 pr_debug("no route\n");
 371         }
 372 }
 373
 374 /* Returns the number of consecutive initial bits that match in the 2 ipv6
 375  * addresses.
 376  */
 377 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
 378                                          union sctp_addr *s2)
 379 {
 380         return ipv6_addr_diff(&s1->v6.sin6_addr, &s2->v6.sin6_addr);
 381 }
 382
 383 /* Fills in the source address(saddr) based on the destination address(daddr)
 384  * and asoc's bind address list.
 385  */
 386 static void sctp_v6_get_saddr(struct sctp_sock *sk,
 387                               struct sctp_transport *t,
 388                               struct flowi *fl)
 389 {
 390         struct flowi6 *fl6 = &fl->u.ip6;
 391         union sctp_addr *saddr = &t->saddr;
 392
 393         pr_debug("%s: asoc:%p dst:%p\n", __func__, t->asoc, t->dst);
 394
 395         if (t->dst) {
 396                 saddr->v6.sin6_family = AF_INET6;
 397                 saddr->v6.sin6_addr = fl6->saddr;
 398         }
 399 }
 400
 401 /* Make a copy of all potential local addresses. */
 402 static void sctp_v6_copy_addrlist(struct list_head *addrlist,
 403                                   struct net_device *dev)
 404 {
 405         struct inet6_dev *in6_dev;
 406         struct inet6_ifaddr *ifp;
 407         struct sctp_sockaddr_entry *addr;
 408
 409         rcu_read_lock();
 410         if ((in6_dev = __in6_dev_get(dev)) == NULL) {
 411                 rcu_read_unlock();
 412                 return;
 413         }
 414
 415         read_lock_bh(&in6_dev->lock);
 416         list_for_each_entry(ifp, &in6_dev->addr_list, if_list) {
 417                 /* Add the address to the local list.  */
 418                 addr = kzalloc(sizeof(*addr), GFP_ATOMIC);
 419                 if (addr) {
 420                         addr->a.v6.sin6_family = AF_INET6;
 421                         addr->a.v6.sin6_addr = ifp->addr;
 422                         addr->a.v6.sin6_scope_id = dev->ifindex;
 423                         addr->valid = 1;
 424                         INIT_LIST_HEAD(&addr->list);
 425                         list_add_tail(&addr->list, addrlist);
 426                 }
 427         }
 428
 429         read_unlock_bh(&in6_dev->lock);
 430         rcu_read_unlock();
 431 }
 432
 433 /* Initialize a sockaddr_storage from in incoming skb. */
 434 static void sctp_v6_from_skb(union sctp_addr *addr, struct sk_buff *skb,
 435                              int is_saddr)
 436 {
 437         __be16 *port;
 438         struct sctphdr *sh;
 439
 440         port = &addr->v6.sin6_port;
 441         addr->v6.sin6_family = AF_INET6;
 442         addr->v6.sin6_flowinfo = 0; /* FIXME */
 443         addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif;
 444
 445         sh = sctp_hdr(skb);
 446         if (is_saddr) {
 447                 *port  = sh->source;
 448                 addr->v6.sin6_addr = ipv6_hdr(skb)->saddr;
 449         } else {
 450                 *port = sh->dest;
 451                 addr->v6.sin6_addr = ipv6_hdr(skb)->daddr;
 452         }
 453 }
 454
 455 /* Initialize an sctp_addr from a socket. */
 456 static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
 457 {
 458         addr->v6.sin6_family = AF_INET6;
 459         addr->v6.sin6_port = 0;
 460         addr->v6.sin6_addr = sk->sk_v6_rcv_saddr;
 461 }
 462
 463 /* Initialize sk->sk_rcv_saddr from sctp_addr. */
 464 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
 465 {
 466         if (addr->sa.sa_family == AF_INET) {
 467                 sk->sk_v6_rcv_saddr.s6_addr32[0] = 0;
 468                 sk->sk_v6_rcv_saddr.s6_addr32[1] = 0;
 469                 sk->sk_v6_rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
 470                 sk->sk_v6_rcv_saddr.s6_addr32[3] =
 471                         addr->v4.sin_addr.s_addr;
 472         } else {
 473                 sk->sk_v6_rcv_saddr = addr->v6.sin6_addr;
 474         }
 475 }
 476
 477 /* Initialize sk->sk_daddr from sctp_addr. */
 478 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
 479 {
 480         if (addr->sa.sa_family == AF_INET) {
 481                 sk->sk_v6_daddr.s6_addr32[0] = 0;
 482                 sk->sk_v6_daddr.s6_addr32[1] = 0;
 483                 sk->sk_v6_daddr.s6_addr32[2] = htonl(0x0000ffff);
 484                 sk->sk_v6_daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
 485         } else {
 486                 sk->sk_v6_daddr = addr->v6.sin6_addr;
 487         }
 488 }
 489
 490 /* Initialize a sctp_addr from an address parameter. */
 491 static bool sctp_v6_from_addr_param(union sctp_addr *addr,
 492                                     union sctp_addr_param *param,
 493                                     __be16 port, int iif)
 494 {
 495         if (ntohs(param->v6.param_hdr.length) < sizeof(struct sctp_ipv6addr_param))
 496                 return false;
 497
 498         addr->v6.sin6_family = AF_INET6;
 499         addr->v6.sin6_port = port;
 500         addr->v6.sin6_flowinfo = 0; /* BUG */
 501         addr->v6.sin6_addr = param->v6.addr;
 502         addr->v6.sin6_scope_id = iif;
 503
 504         return true;
 505 }
 506
 507 /* Initialize an address parameter from a sctp_addr and return the length
 508  * of the address parameter.
 509  */
 510 static int sctp_v6_to_addr_param(const union sctp_addr *addr,
 511                                  union sctp_addr_param *param)
 512 {
 513         int length = sizeof(sctp_ipv6addr_param_t);
 514
 515         param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
 516         param->v6.param_hdr.length = htons(length);
 517         param->v6.addr = addr->v6.sin6_addr;
 518
 519         return length;
 520 }
 521
 522 /* Initialize a sctp_addr from struct in6_addr. */
 523 static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr,
 524                               __be16 port)
 525 {
 526         addr->sa.sa_family = AF_INET6;
 527         addr->v6.sin6_port = port;
 528         addr->v6.sin6_flowinfo = 0;
 529         addr->v6.sin6_addr = *saddr;
 530         addr->v6.sin6_scope_id = 0;
 531 }
 532
 533 static int __sctp_v6_cmp_addr(const union sctp_addr *addr1,
 534                               const union sctp_addr *addr2)
 535 {
 536         if (addr1->sa.sa_family != addr2->sa.sa_family) {
 537                 if (addr1->sa.sa_family == AF_INET &&
 538                     addr2->sa.sa_family == AF_INET6 &&
 539                     ipv6_addr_v4mapped(&addr2->v6.sin6_addr) &&
 540                     addr2->v6.sin6_addr.s6_addr32[3] ==
 541                     addr1->v4.sin_addr.s_addr)
 542                         return 1;
 543
 544                 if (addr2->sa.sa_family == AF_INET &&
 545                     addr1->sa.sa_family == AF_INET6 &&
 546                     ipv6_addr_v4mapped(&addr1->v6.sin6_addr) &&
 547                     addr1->v6.sin6_addr.s6_addr32[3] ==
 548                     addr2->v4.sin_addr.s_addr)
 549                         return 1;
 550
 551                 return 0;
 552         }
 553
 554         if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
 555                 return 0;
 556
 557         /* If this is a linklocal address, compare the scope_id. */
 558         if ((ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) &&
 559             addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
 560             addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)
 561                 return 0;
 562
 563         return 1;
 564 }
 565
 566 /* Compare addresses exactly.
 567  * v4-mapped-v6 is also in consideration.
 568  */
 569 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
 570                             const union sctp_addr *addr2)
 571 {
 572         return __sctp_v6_cmp_addr(addr1, addr2) &&
 573                addr1->v6.sin6_port == addr2->v6.sin6_port;
 574 }
 575
 576 /* Initialize addr struct to INADDR_ANY. */
 577 static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port)
 578 {
 579         memset(addr, 0x00, sizeof(union sctp_addr));
 580         addr->v6.sin6_family = AF_INET6;
 581         addr->v6.sin6_port = port;
 582 }
 583
 584 /* Is this a wildcard address? */
 585 static int sctp_v6_is_any(const union sctp_addr *addr)
 586 {
 587         return ipv6_addr_any(&addr->v6.sin6_addr);
 588 }
 589
 590 /* Should this be available for binding?   */
 591 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
 592 {
 593         int type;
 594         const struct in6_addr *in6 = (const struct in6_addr *)&addr->v6.sin6_addr;
 595
 596         type = ipv6_addr_type(in6);
 597         if (IPV6_ADDR_ANY == type)
 598                 return 1;
 599         if (type == IPV6_ADDR_MAPPED) {
 600                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
 601                         return 0;
 602                 sctp_v6_map_v4(addr);
 603                 return sctp_get_af_specific(AF_INET)->available(addr, sp);
 604         }
 605         if (!(type & IPV6_ADDR_UNICAST))
 606                 return 0;
 607
 608         return ipv6_chk_addr(sock_net(&sp->inet.sk), in6, NULL, 0);
 609 }
 610
 611 /* This function checks if the address is a valid address to be used for
 612  * SCTP.
 613  *
 614  * Output:
 615  * Return 0 - If the address is a non-unicast or an illegal address.
 616  * Return 1 - If the address is a unicast.
 617  */
 618 static int sctp_v6_addr_valid(union sctp_addr *addr,
 619                               struct sctp_sock *sp,
 620                               const struct sk_buff *skb)
 621 {
 622         int ret = ipv6_addr_type(&addr->v6.sin6_addr);
 623
 624         /* Support v4-mapped-v6 address. */
 625         if (ret == IPV6_ADDR_MAPPED) {
 626                 /* Note: This routine is used in input, so v4-mapped-v6
 627                  * are disallowed here when there is no sctp_sock.
 628                  */
 629                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
 630                         return 0;
 631                 sctp_v6_map_v4(addr);
 632                 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb);
 633         }
 634
 635         /* Is this a non-unicast address */
 636         if (!(ret & IPV6_ADDR_UNICAST))
 637                 return 0;
 638
 639         return 1;
 640 }
 641
 642 /* What is the scope of 'addr'?  */
 643 static sctp_scope_t sctp_v6_scope(union sctp_addr *addr)
 644 {
 645         int v6scope;
 646         sctp_scope_t retval;
 647
 648         /* The IPv6 scope is really a set of bit fields.
 649          * See IFA_* in <net/if_inet6.h>.  Map to a generic SCTP scope.
 650          */
 651
 652         v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
 653         switch (v6scope) {
 654         case IFA_HOST:
 655                 retval = SCTP_SCOPE_LOOPBACK;
 656                 break;
 657         case IFA_LINK:
 658                 retval = SCTP_SCOPE_LINK;
 659                 break;
 660         case IFA_SITE:
 661                 retval = SCTP_SCOPE_PRIVATE;
 662                 break;
 663         default:
 664                 retval = SCTP_SCOPE_GLOBAL;
 665                 break;
 666         }
 667
 668         return retval;
 669 }
 670
 671 /* Create and initialize a new sk for the socket to be returned by accept(). */
 672 static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
 673                                              struct sctp_association *asoc)
 674 {
 675         struct sock *newsk;
 676         struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
 677         struct sctp6_sock *newsctp6sk;
 678         struct ipv6_txoptions *opt;
 679
 680         newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot, 0);
 681         if (!newsk)
 682                 goto out;
 683
 684         sock_init_data(NULL, newsk);
 685
 686         sctp_copy_sock(newsk, sk, asoc);
 687         sock_reset_flag(sk, SOCK_ZAPPED);
 688
 689         newsctp6sk = (struct sctp6_sock *)newsk;
 690         inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
 691
 692         sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped;
 693
 694         newnp = inet6_sk(newsk);
 695
 696         memcpy(newnp, np, sizeof(struct ipv6_pinfo));
 697         newnp->ipv6_mc_list = NULL;
 698         newnp->ipv6_ac_list = NULL;
 699         newnp->ipv6_fl_list = NULL;
 700
 701         rcu_read_lock();
 702         opt = rcu_dereference(np->opt);
 703         if (opt)
 704                 opt = ipv6_dup_options(newsk, opt);
 705         RCU_INIT_POINTER(newnp->opt, opt);
 706         rcu_read_unlock();
 707
 708         /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
 709          * and getpeername().
 710          */
 711         sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
 712
 713         newsk->sk_v6_rcv_saddr = sk->sk_v6_rcv_saddr;
 714
 715         sk_refcnt_debug_inc(newsk);
 716
 717         if (newsk->sk_prot->init(newsk)) {
 718                 sk_common_release(newsk);
 719                 newsk = NULL;
 720         }
 721
 722 out:
 723         return newsk;
 724 }
 725
 726 /* Format a sockaddr for return to user space. This makes sure the return is
 727  * AF_INET or AF_INET6 depending on the SCTP_I_WANT_MAPPED_V4_ADDR option.
 728  */
 729 static int sctp_v6_addr_to_user(struct sctp_sock *sp, union sctp_addr *addr)
 730 {
 731         if (sp->v4mapped) {
 732                 if (addr->sa.sa_family == AF_INET)
 733                         sctp_v4_map_v6(addr);
 734         } else {
 735                 if (addr->sa.sa_family == AF_INET6 &&
 736                     ipv6_addr_v4mapped(&addr->v6.sin6_addr))
 737                         sctp_v6_map_v4(addr);
 738         }
 739
 740         if (addr->sa.sa_family == AF_INET) {
 741                 memset(addr->v4.sin_zero, 0, sizeof(addr->v4.sin_zero));
 742                 return sizeof(struct sockaddr_in);
 743         }
 744         return sizeof(struct sockaddr_in6);
 745 }
 746
 747 /* Where did this skb come from?  */
 748 static int sctp_v6_skb_iif(const struct sk_buff *skb)
 749 {
 750         struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb;
 751         return opt->iif;
 752 }
 753
 754 /* Was this packet marked by Explicit Congestion Notification? */
 755 static int sctp_v6_is_ce(const struct sk_buff *skb)
 756 {
 757         return *((__u32 *)(ipv6_hdr(skb))) & htonl(1 << 20);
 758 }
 759
 760 /* Dump the v6 addr to the seq file. */
 761 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
 762 {
 763         seq_printf(seq, "%pI6 ", &addr->v6.sin6_addr);
 764 }
 765
 766 static void sctp_v6_ecn_capable(struct sock *sk)
 767 {
 768         inet6_sk(sk)->tclass |= INET_ECN_ECT_0;
 769 }
 770
 771 /* Initialize a PF_INET msgname from a ulpevent. */
 772 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
 773                                      char *msgname, int *addrlen)
 774 {
 775         union sctp_addr *addr;
 776         struct sctp_association *asoc;
 777         union sctp_addr *paddr;
 778
 779         if (!msgname)
 780                 return;
 781
 782         addr = (union sctp_addr *)msgname;
 783         asoc = event->asoc;
 784         paddr = &asoc->peer.primary_addr;
 785
 786         if (paddr->sa.sa_family == AF_INET) {
 787                 addr->v4.sin_family = AF_INET;
 788                 addr->v4.sin_port = htons(asoc->peer.port);
 789                 addr->v4.sin_addr = paddr->v4.sin_addr;
 790         } else {
 791                 addr->v6.sin6_family = AF_INET6;
 792                 addr->v6.sin6_flowinfo = 0;
 793                 if (ipv6_addr_type(&paddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
 794                         addr->v6.sin6_scope_id = paddr->v6.sin6_scope_id;
 795                 else
 796                         addr->v6.sin6_scope_id = 0;
 797                 addr->v6.sin6_port = htons(asoc->peer.port);
 798                 addr->v6.sin6_addr = paddr->v6.sin6_addr;
 799         }
 800
 801         *addrlen = sctp_v6_addr_to_user(sctp_sk(asoc->base.sk), addr);
 802 }
 803
 804 /* Initialize a msg_name from an inbound skb. */
 805 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
 806                                    int *addr_len)
 807 {
 808         union sctp_addr *addr;
 809         struct sctphdr *sh;
 810
 811         if (!msgname)
 812                 return;
 813
 814         addr = (union sctp_addr *)msgname;
 815         sh = sctp_hdr(skb);
 816
 817         if (ip_hdr(skb)->version == 4) {
 818                 addr->v4.sin_family = AF_INET;
 819                 addr->v4.sin_port = sh->source;
 820                 addr->v4.sin_addr.s_addr =  ip_hdr(skb)->saddr;
 821         } else {
 822                 addr->v6.sin6_family = AF_INET6;
 823                 addr->v6.sin6_flowinfo = 0;
 824                 addr->v6.sin6_port = sh->source;
 825                 addr->v6.sin6_addr = ipv6_hdr(skb)->saddr;
 826                 if (ipv6_addr_type(&addr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) {
 827                         struct sctp_ulpevent *ev = sctp_skb2event(skb);
 828                         addr->v6.sin6_scope_id = ev->iif;
 829                 } else {
 830                         addr->v6.sin6_scope_id = 0;
 831                 }
 832         }
 833
 834         *addr_len = sctp_v6_addr_to_user(sctp_sk(skb->sk), addr);
 835 }
 836
 837 /* Do we support this AF? */
 838 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
 839 {
 840         switch (family) {
 841         case AF_INET6:
 842                 return 1;
 843         /* v4-mapped-v6 addresses */
 844         case AF_INET:
 845                 if (!__ipv6_only_sock(sctp_opt2sk(sp)))
 846                         return 1;
 847         default:
 848                 return 0;
 849         }
 850 }
 851
 852 /* Address matching with wildcards allowed.  This extra level
 853  * of indirection lets us choose whether a PF_INET6 should
 854  * disallow any v4 addresses if we so choose.
 855  */
 856 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
 857                                const union sctp_addr *addr2,
 858                                struct sctp_sock *opt)
 859 {
 860         struct sock *sk = sctp_opt2sk(opt);
 861         struct sctp_af *af1, *af2;
 862
 863         af1 = sctp_get_af_specific(addr1->sa.sa_family);
 864         af2 = sctp_get_af_specific(addr2->sa.sa_family);
 865
 866         if (!af1 || !af2)
 867                 return 0;
 868
 869         /* If the socket is IPv6 only, v4 addrs will not match */
 870         if (__ipv6_only_sock(sk) && af1 != af2)
 871                 return 0;
 872
 873         /* Today, wildcard AF_INET/AF_INET6. */
 874         if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2))
 875                 return 1;
 876
 877         if (addr1->sa.sa_family == AF_INET && addr2->sa.sa_family == AF_INET)
 878                 return addr1->v4.sin_addr.s_addr == addr2->v4.sin_addr.s_addr;
 879
 880         return __sctp_v6_cmp_addr(addr1, addr2);
 881 }
 882
 883 /* Verify that the provided sockaddr looks bindable.   Common verification,
 884  * has already been taken care of.
 885  */
 886 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
 887 {
 888         struct sctp_af *af;
 889
 890         /* ASSERT: address family has already been verified. */
 891         if (addr->sa.sa_family != AF_INET6)
 892                 af = sctp_get_af_specific(addr->sa.sa_family);
 893         else {
 894                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
 895                 struct net_device *dev;
 896
 897                 if (type & IPV6_ADDR_LINKLOCAL) {
 898                         struct net *net;
 899                         if (!addr->v6.sin6_scope_id)
 900                                 return 0;
 901                         net = sock_net(&opt->inet.sk);
 902                         rcu_read_lock();
 903                         dev = dev_get_by_index_rcu(net, addr->v6.sin6_scope_id);
 904                         if (!dev ||
 905                             !ipv6_chk_addr(net, &addr->v6.sin6_addr, dev, 0)) {
 906                                 rcu_read_unlock();
 907                                 return 0;
 908                         }
 909                         rcu_read_unlock();
 910                 }
 911
 912                 af = opt->pf->af;
 913         }
 914         return af->available(addr, opt);
 915 }
 916
 917 /* Verify that the provided sockaddr looks sendable.   Common verification,
 918  * has already been taken care of.
 919  */
 920 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
 921 {
 922         struct sctp_af *af = NULL;
 923
 924         /* ASSERT: address family has already been verified. */
 925         if (addr->sa.sa_family != AF_INET6)
 926                 af = sctp_get_af_specific(addr->sa.sa_family);
 927         else {
 928                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
 929                 struct net_device *dev;
 930
 931                 if (type & IPV6_ADDR_LINKLOCAL) {
 932                         if (!addr->v6.sin6_scope_id)
 933                                 return 0;
 934                         rcu_read_lock();
 935                         dev = dev_get_by_index_rcu(sock_net(&opt->inet.sk),
 936                                                    addr->v6.sin6_scope_id);
 937                         rcu_read_unlock();
 938                         if (!dev)
 939                                 return 0;
 940                 }
 941                 af = opt->pf->af;
 942         }
 943
 944         return af != NULL;
 945 }
 946
 947 /* Fill in Supported Address Type information for INIT and INIT-ACK
 948  * chunks.   Note: In the future, we may want to look at sock options
 949  * to determine whether a PF_INET6 socket really wants to have IPV4
 950  * addresses.
 951  * Returns number of addresses supported.
 952  */
 953 static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
 954                                       __be16 *types)
 955 {
 956         types[0] = SCTP_PARAM_IPV6_ADDRESS;
 957         if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) {
 958                 types[1] = SCTP_PARAM_IPV4_ADDRESS;
 959                 return 2;
 960         }
 961         return 1;
 962 }
 963
 964 /* Handle SCTP_I_WANT_MAPPED_V4_ADDR for getpeername() and getsockname() */
 965 static int sctp_getname(struct socket *sock, struct sockaddr *uaddr,
 966                         int *uaddr_len, int peer)
 967 {
 968         int rc;
 969
 970         rc = inet6_getname(sock, uaddr, uaddr_len, peer);
 971
 972         if (rc != 0)
 973                 return rc;
 974
 975         *uaddr_len = sctp_v6_addr_to_user(sctp_sk(sock->sk),
 976                                           (union sctp_addr *)uaddr);
 977
 978         return rc;
 979 }
 980
 981 static const struct proto_ops inet6_seqpacket_ops = {
 982         .family            = PF_INET6,
 983         .owner             = THIS_MODULE,
 984         .release           = inet6_release,
 985         .bind              = inet6_bind,
 986         .connect           = sctp_inet_connect,
 987         .socketpair        = sock_no_socketpair,
 988         .accept            = inet_accept,
 989         .getname           = sctp_getname,
 990         .poll              = sctp_poll,
 991         .ioctl             = inet6_ioctl,
 992         .listen            = sctp_inet_listen,
 993         .shutdown          = inet_shutdown,
 994         .setsockopt        = sock_common_setsockopt,
 995         .getsockopt        = sock_common_getsockopt,
 996         .sendmsg           = inet_sendmsg,
 997         .recvmsg           = sock_common_recvmsg,
 998         .mmap              = sock_no_mmap,
 999 #ifdef CONFIG_COMPAT
1000         .compat_setsockopt = compat_sock_common_setsockopt,
1001         .compat_getsockopt = compat_sock_common_getsockopt,
1002 #endif
1003 };
1004
1005 static struct inet_protosw sctpv6_seqpacket_protosw = {
1006         .type          = SOCK_SEQPACKET,
1007         .protocol      = IPPROTO_SCTP,
1008         .prot          = &sctpv6_prot,
1009         .ops           = &inet6_seqpacket_ops,
1010         .flags         = SCTP_PROTOSW_FLAG
1011 };
1012 static struct inet_protosw sctpv6_stream_protosw = {
1013         .type          = SOCK_STREAM,
1014         .protocol      = IPPROTO_SCTP,
1015         .prot          = &sctpv6_prot,
1016         .ops           = &inet6_seqpacket_ops,
1017         .flags         = SCTP_PROTOSW_FLAG,
1018 };
1019
1020 static int sctp6_rcv(struct sk_buff *skb)
1021 {
1022         return sctp_rcv(skb) ? -1 : 0;
1023 }
1024
1025 static const struct inet6_protocol sctpv6_protocol = {
1026         .handler      = sctp6_rcv,
1027         .err_handler  = sctp_v6_err,
1028         .flags        = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
1029 };
1030
1031 static struct sctp_af sctp_af_inet6 = {
1032         .sa_family         = AF_INET6,
1033         .sctp_xmit         = sctp_v6_xmit,
1034         .setsockopt        = ipv6_setsockopt,
1035         .getsockopt        = ipv6_getsockopt,
1036         .get_dst           = sctp_v6_get_dst,
1037         .get_saddr         = sctp_v6_get_saddr,
1038         .copy_addrlist     = sctp_v6_copy_addrlist,
1039         .from_skb          = sctp_v6_from_skb,
1040         .from_sk           = sctp_v6_from_sk,
1041         .from_addr_param   = sctp_v6_from_addr_param,
1042         .to_addr_param     = sctp_v6_to_addr_param,
1043         .cmp_addr          = sctp_v6_cmp_addr,
1044         .scope             = sctp_v6_scope,
1045         .addr_valid        = sctp_v6_addr_valid,
1046         .inaddr_any        = sctp_v6_inaddr_any,
1047         .is_any            = sctp_v6_is_any,
1048         .available         = sctp_v6_available,
1049         .skb_iif           = sctp_v6_skb_iif,
1050         .is_ce             = sctp_v6_is_ce,
1051         .seq_dump_addr     = sctp_v6_seq_dump_addr,
1052         .ecn_capable       = sctp_v6_ecn_capable,
1053         .net_header_len    = sizeof(struct ipv6hdr),
1054         .sockaddr_len      = sizeof(struct sockaddr_in6),
1055 #ifdef CONFIG_COMPAT
1056         .compat_setsockopt = compat_ipv6_setsockopt,
1057         .compat_getsockopt = compat_ipv6_getsockopt,
1058 #endif
1059 };
1060
1061 static struct sctp_pf sctp_pf_inet6 = {
1062         .event_msgname = sctp_inet6_event_msgname,
1063         .skb_msgname   = sctp_inet6_skb_msgname,
1064         .af_supported  = sctp_inet6_af_supported,
1065         .cmp_addr      = sctp_inet6_cmp_addr,
1066         .bind_verify   = sctp_inet6_bind_verify,
1067         .send_verify   = sctp_inet6_send_verify,
1068         .supported_addrs = sctp_inet6_supported_addrs,
1069         .create_accept_sk = sctp_v6_create_accept_sk,
1070         .addr_to_user  = sctp_v6_addr_to_user,
1071         .to_sk_saddr   = sctp_v6_to_sk_saddr,
1072         .to_sk_daddr   = sctp_v6_to_sk_daddr,
1073         .af            = &sctp_af_inet6,
1074 };
1075
1076 /* Initialize IPv6 support and register with socket layer.  */
1077 void sctp_v6_pf_init(void)
1078 {
1079         /* Register the SCTP specific PF_INET6 functions. */
1080         sctp_register_pf(&sctp_pf_inet6, PF_INET6);
1081
1082         /* Register the SCTP specific AF_INET6 functions. */
1083         sctp_register_af(&sctp_af_inet6);
1084 }
1085
1086 void sctp_v6_pf_exit(void)
1087 {
1088         list_del(&sctp_af_inet6.list);
1089 }
1090
1091 /* Initialize IPv6 support and register with socket layer.  */
1092 int sctp_v6_protosw_init(void)
1093 {
1094         int rc;
1095
1096         rc = proto_register(&sctpv6_prot, 1);
1097         if (rc)
1098                 return rc;
1099
1100         /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
1101         inet6_register_protosw(&sctpv6_seqpacket_protosw);
1102         inet6_register_protosw(&sctpv6_stream_protosw);
1103
1104         return 0;
1105 }
1106
1107 void sctp_v6_protosw_exit(void)
1108 {
1109         inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
1110         inet6_unregister_protosw(&sctpv6_stream_protosw);
1111         proto_unregister(&sctpv6_prot);
1112 }
1113
1114
1115 /* Register with inet6 layer. */
1116 int sctp_v6_add_protocol(void)
1117 {
1118         /* Register notifier for inet6 address additions/deletions. */
1119         register_inet6addr_notifier(&sctp_inet6addr_notifier);
1120
1121         if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
1122                 return -EAGAIN;
1123
1124         return 0;
1125 }
1126
1127 /* Unregister with inet6 layer. */
1128 void sctp_v6_del_protocol(void)
1129 {
1130         inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
1131         unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1132 }