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 <linux-sctp@vger.kernel.org>
  31  *
  32  * Written or modified by:
  33  *    Le Yanqun             <yanqun.le@nokia.com>
  34  *    Hui Huang             <hui.huang@nokia.com>
  35  *    La Monte H.P. Yarroll <piggy@acm.org>
  36  *    Sridhar Samudrala     <sri@us.ibm.com>
  37  *    Jon Grimm             <jgrimm@us.ibm.com>
  38  *    Ardelle Fan           <ardelle.fan@intel.com>
  39  *
  40  * Based on:
  41  *      linux/net/ipv6/tcp_ipv6.c
  42  */
  43
  44 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  45
  46 #include <linux/module.h>
  47 #include <linux/errno.h>
  48 #include <linux/types.h>
  49 #include <linux/socket.h>
  50 #include <linux/sockios.h>
  51 #include <linux/net.h>
  52 #include <linux/in.h>
  53 #include <linux/in6.h>
  54 #include <linux/netdevice.h>
  55 #include <linux/init.h>
  56 #include <linux/ipsec.h>
  57 #include <linux/slab.h>
  58
  59 #include <linux/ipv6.h>
  60 #include <linux/icmpv6.h>
  61 #include <linux/random.h>
  62 #include <linux/seq_file.h>
  63
  64 #include <net/protocol.h>
  65 #include <net/ndisc.h>
  66 #include <net/ip.h>
  67 #include <net/ipv6.h>
  68 #include <net/transp_v6.h>
  69 #include <net/addrconf.h>
  70 #include <net/ip6_route.h>
  71 #include <net/inet_common.h>
  72 #include <net/inet_ecn.h>
  73 #include <net/sctp/sctp.h>
  74
  75 #include <asm/uaccess.h>
  76
  77 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
  78                                          union sctp_addr *s2);
  79 static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr,
  80                               __be16 port);
  81 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
  82                             const union sctp_addr *addr2);
  83
  84 /* Event handler for inet6 address addition/deletion events.
  85  * The sctp_local_addr_list needs to be protocted by a spin lock since
  86  * multiple notifiers (say IPv4 and IPv6) may be running at the same
  87  * time and thus corrupt the list.
  88  * The reader side is protected with RCU.
  89  */
  90 static int sctp_inet6addr_event(struct notifier_block *this, unsigned long ev,
  91                                 void *ptr)
  92 {
  93         struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
  94         struct sctp_sockaddr_entry *addr = NULL;
  95         struct sctp_sockaddr_entry *temp;
  96         struct net *net = dev_net(ifa->idev->dev);
  97         int found = 0;
  98
  99         switch (ev) {
 100         case NETDEV_UP:
 101                 addr = kmalloc(sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC);
 102                 if (addr) {
 103                         addr->a.v6.sin6_family = AF_INET6;
 104                         addr->a.v6.sin6_port = 0;
 105                         addr->a.v6.sin6_addr = ifa->addr;
 106                         addr->a.v6.sin6_scope_id = ifa->idev->dev->ifindex;
 107                         addr->valid = 1;
 108                         spin_lock_bh(&net->sctp.local_addr_lock);
 109                         list_add_tail_rcu(&addr->list, &net->sctp.local_addr_list);
 110                         sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_NEW);
 111                         spin_unlock_bh(&net->sctp.local_addr_lock);
 112                 }
 113                 break;
 114         case NETDEV_DOWN:
 115                 spin_lock_bh(&net->sctp.local_addr_lock);
 116                 list_for_each_entry_safe(addr, temp,
 117                                         &net->sctp.local_addr_list, list) {
 118                         if (addr->a.sa.sa_family == AF_INET6 &&
 119                                         ipv6_addr_equal(&addr->a.v6.sin6_addr,
 120                                                 &ifa->addr)) {
 121                                 sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_DEL);
 122                                 found = 1;
 123                                 addr->valid = 0;
 124                                 list_del_rcu(&addr->list);
 125                                 break;
 126                         }
 127                 }
 128                 spin_unlock_bh(&net->sctp.local_addr_lock);
 129                 if (found)
 130                         kfree_rcu(addr, rcu);
 131                 break;
 132         }
 133
 134         return NOTIFY_DONE;
 135 }
 136
 137 static struct notifier_block sctp_inet6addr_notifier = {
 138         .notifier_call = sctp_inet6addr_event,
 139 };
 140
 141 /* ICMP error handler. */
 142 static void sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 143                         u8 type, u8 code, int offset, __be32 info)
 144 {
 145         struct inet6_dev *idev;
 146         struct sock *sk;
 147         struct sctp_association *asoc;
 148         struct sctp_transport *transport;
 149         struct ipv6_pinfo *np;
 150         __u16 saveip, savesctp;
 151         int err;
 152         struct net *net = dev_net(skb->dev);
 153
 154         idev = in6_dev_get(skb->dev);
 155
 156         /* Fix up skb to look at the embedded net header. */
 157         saveip   = skb->network_header;
 158         savesctp = skb->transport_header;
 159         skb_reset_network_header(skb);
 160         skb_set_transport_header(skb, offset);
 161         sk = sctp_err_lookup(net, AF_INET6, skb, sctp_hdr(skb), &asoc, &transport);
 162         /* Put back, the original pointers. */
 163         skb->network_header   = saveip;
 164         skb->transport_header = savesctp;
 165         if (!sk) {
 166                 ICMP6_INC_STATS_BH(net, idev, ICMP6_MIB_INERRORS);
 167                 goto out;
 168         }
 169
 170         /* Warning:  The sock lock is held.  Remember to call
 171          * sctp_err_finish!
 172          */
 173
 174         switch (type) {
 175         case ICMPV6_PKT_TOOBIG:
 176                 sctp_icmp_frag_needed(sk, asoc, transport, ntohl(info));
 177                 goto out_unlock;
 178         case ICMPV6_PARAMPROB:
 179                 if (ICMPV6_UNK_NEXTHDR == code) {
 180                         sctp_icmp_proto_unreachable(sk, asoc, transport);
 181                         goto out_unlock;
 182                 }
 183                 break;
 184         case NDISC_REDIRECT:
 185                 sctp_icmp_redirect(sk, transport, skb);
 186                 goto out_unlock;
 187         default:
 188                 break;
 189         }
 190
 191         np = inet6_sk(sk);
 192         icmpv6_err_convert(type, code, &err);
 193         if (!sock_owned_by_user(sk) && np->recverr) {
 194                 sk->sk_err = err;
 195                 sk->sk_error_report(sk);
 196         } else {  /* Only an error on timeout */
 197                 sk->sk_err_soft = err;
 198         }
 199
 200 out_unlock:
 201         sctp_err_finish(sk, asoc);
 202 out:
 203         if (likely(idev != NULL))
 204                 in6_dev_put(idev);
 205 }
 206
 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 = &transport->fl.u.ip6;
 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->local_df = 1;
 220
 221         SCTP_INC_STATS(sock_net(sk), SCTP_MIB_OUTSCTPPACKS);
 222
 223         return ip6_xmit(sk, skb, fl6, np->opt, np->tclass);
 224 }
 225
 226 /* Returns the dst cache entry for the given source and destination ip
 227  * addresses.
 228  */
 229 static void sctp_v6_get_dst(struct sctp_transport *t, union sctp_addr *saddr,
 230                             struct flowi *fl, struct sock *sk)
 231 {
 232         struct sctp_association *asoc = t->asoc;
 233         struct dst_entry *dst = NULL;
 234         struct flowi6 *fl6 = &fl->u.ip6;
 235         struct sctp_bind_addr *bp;
 236         struct ipv6_pinfo *np = inet6_sk(sk);
 237         struct sctp_sockaddr_entry *laddr;
 238         union sctp_addr *baddr = NULL;
 239         union sctp_addr *daddr = &t->ipaddr;
 240         union sctp_addr dst_saddr;
 241         struct in6_addr *final_p, final;
 242         __u8 matchlen = 0;
 243         __u8 bmatchlen;
 244         sctp_scope_t scope;
 245
 246         memset(fl6, 0, sizeof(struct flowi6));
 247         fl6->daddr = daddr->v6.sin6_addr;
 248         fl6->fl6_dport = daddr->v6.sin6_port;
 249         fl6->flowi6_proto = IPPROTO_SCTP;
 250         if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
 251                 fl6->flowi6_oif = daddr->v6.sin6_scope_id;
 252
 253         pr_debug("%s: dst=%pI6 ", __func__, &fl6->daddr);
 254
 255         if (asoc)
 256                 fl6->fl6_sport = htons(asoc->base.bind_addr.port);
 257
 258         if (saddr) {
 259                 fl6->saddr = saddr->v6.sin6_addr;
 260                 fl6->fl6_sport = saddr->v6.sin6_port;
 261
 262                 pr_debug("src=%pI6 - ", &fl6->saddr);
 263         }
 264
 265         final_p = fl6_update_dst(fl6, np->opt, &final);
 266         dst = ip6_dst_lookup_flow(sk, fl6, final_p, false);
 267         if (!asoc || saddr)
 268                 goto out;
 269
 270         bp = &asoc->base.bind_addr;
 271         scope = sctp_scope(daddr);
 272         /* ip6_dst_lookup has filled in the fl6->saddr for us.  Check
 273          * to see if we can use it.
 274          */
 275         if (!IS_ERR(dst)) {
 276                 /* Walk through the bind address list and look for a bind
 277                  * address that matches the source address of the returned dst.
 278                  */
 279                 sctp_v6_to_addr(&dst_saddr, &fl6->saddr, htons(bp->port));
 280                 rcu_read_lock();
 281                 list_for_each_entry_rcu(laddr, &bp->address_list, list) {
 282                         if (!laddr->valid || (laddr->state != SCTP_ADDR_SRC))
 283                                 continue;
 284
 285                         /* Do not compare against v4 addrs */
 286                         if ((laddr->a.sa.sa_family == AF_INET6) &&
 287                             (sctp_v6_cmp_addr(&dst_saddr, &laddr->a))) {
 288                                 rcu_read_unlock();
 289                                 goto out;
 290                         }
 291                 }
 292                 rcu_read_unlock();
 293                 /* None of the bound addresses match the source address of the
 294                  * dst. So release it.
 295                  */
 296                 dst_release(dst);
 297                 dst = NULL;
 298         }
 299
 300         /* Walk through the bind address list and try to get the
 301          * best source address for a given destination.
 302          */
 303         rcu_read_lock();
 304         list_for_each_entry_rcu(laddr, &bp->address_list, list) {
 305                 if (!laddr->valid)
 306                         continue;
 307                 if ((laddr->state == SCTP_ADDR_SRC) &&
 308                     (laddr->a.sa.sa_family == AF_INET6) &&
 309                     (scope <= sctp_scope(&laddr->a))) {
 310                         bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
 311                         if (!baddr || (matchlen < bmatchlen)) {
 312                                 baddr = &laddr->a;
 313                                 matchlen = bmatchlen;
 314                         }
 315                 }
 316         }
 317         rcu_read_unlock();
 318
 319         if (baddr) {
 320                 fl6->saddr = baddr->v6.sin6_addr;
 321                 fl6->fl6_sport = baddr->v6.sin6_port;
 322                 final_p = fl6_update_dst(fl6, np->opt, &final);
 323                 dst = ip6_dst_lookup_flow(sk, fl6, final_p, false);
 324         }
 325
 326 out:
 327         if (!IS_ERR_OR_NULL(dst)) {
 328                 struct rt6_info *rt;
 329
 330                 rt = (struct rt6_info *)dst;
 331                 t->dst = dst;
 332                 t->dst_cookie = rt->rt6i_node ? rt->rt6i_node->fn_sernum : 0;
 333                 pr_debug("rt6_dst:%pI6 rt6_src:%pI6\n", &rt->rt6i_dst.addr,
 334                          &fl6->saddr);
 335         } else {
 336                 t->dst = NULL;
 337
 338                 pr_debug("no route\n");
 339         }
 340 }
 341
 342 /* Returns the number of consecutive initial bits that match in the 2 ipv6
 343  * addresses.
 344  */
 345 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
 346                                          union sctp_addr *s2)
 347 {
 348         return ipv6_addr_diff(&s1->v6.sin6_addr, &s2->v6.sin6_addr);
 349 }
 350
 351 /* Fills in the source address(saddr) based on the destination address(daddr)
 352  * and asoc's bind address list.
 353  */
 354 static void sctp_v6_get_saddr(struct sctp_sock *sk,
 355                               struct sctp_transport *t,
 356                               struct flowi *fl)
 357 {
 358         struct flowi6 *fl6 = &fl->u.ip6;
 359         union sctp_addr *saddr = &t->saddr;
 360
 361         pr_debug("%s: asoc:%p dst:%p\n", __func__, t->asoc, t->dst);
 362
 363         if (t->dst) {
 364                 saddr->v6.sin6_family = AF_INET6;
 365                 saddr->v6.sin6_addr = fl6->saddr;
 366         }
 367 }
 368
 369 /* Make a copy of all potential local addresses. */
 370 static void sctp_v6_copy_addrlist(struct list_head *addrlist,
 371                                   struct net_device *dev)
 372 {
 373         struct inet6_dev *in6_dev;
 374         struct inet6_ifaddr *ifp;
 375         struct sctp_sockaddr_entry *addr;
 376
 377         rcu_read_lock();
 378         if ((in6_dev = __in6_dev_get(dev)) == NULL) {
 379                 rcu_read_unlock();
 380                 return;
 381         }
 382
 383         read_lock_bh(&in6_dev->lock);
 384         list_for_each_entry(ifp, &in6_dev->addr_list, if_list) {
 385                 /* Add the address to the local list.  */
 386                 addr = kzalloc(sizeof(*addr), GFP_ATOMIC);
 387                 if (addr) {
 388                         addr->a.v6.sin6_family = AF_INET6;
 389                         addr->a.v6.sin6_port = 0;
 390                         addr->a.v6.sin6_addr = ifp->addr;
 391                         addr->a.v6.sin6_scope_id = dev->ifindex;
 392                         addr->valid = 1;
 393                         INIT_LIST_HEAD(&addr->list);
 394                         list_add_tail(&addr->list, addrlist);
 395                 }
 396         }
 397
 398         read_unlock_bh(&in6_dev->lock);
 399         rcu_read_unlock();
 400 }
 401
 402 /* Initialize a sockaddr_storage from in incoming skb. */
 403 static void sctp_v6_from_skb(union sctp_addr *addr,struct sk_buff *skb,
 404                              int is_saddr)
 405 {
 406         __be16 *port;
 407         struct sctphdr *sh;
 408
 409         port = &addr->v6.sin6_port;
 410         addr->v6.sin6_family = AF_INET6;
 411         addr->v6.sin6_flowinfo = 0; /* FIXME */
 412         addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif;
 413
 414         sh = sctp_hdr(skb);
 415         if (is_saddr) {
 416                 *port  = sh->source;
 417                 addr->v6.sin6_addr = ipv6_hdr(skb)->saddr;
 418         } else {
 419                 *port = sh->dest;
 420                 addr->v6.sin6_addr = ipv6_hdr(skb)->daddr;
 421         }
 422 }
 423
 424 /* Initialize an sctp_addr from a socket. */
 425 static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
 426 {
 427         addr->v6.sin6_family = AF_INET6;
 428         addr->v6.sin6_port = 0;
 429         addr->v6.sin6_addr = inet6_sk(sk)->rcv_saddr;
 430 }
 431
 432 /* Initialize sk->sk_rcv_saddr from sctp_addr. */
 433 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
 434 {
 435         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
 436                 inet6_sk(sk)->rcv_saddr.s6_addr32[0] = 0;
 437                 inet6_sk(sk)->rcv_saddr.s6_addr32[1] = 0;
 438                 inet6_sk(sk)->rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
 439                 inet6_sk(sk)->rcv_saddr.s6_addr32[3] =
 440                         addr->v4.sin_addr.s_addr;
 441         } else {
 442                 inet6_sk(sk)->rcv_saddr = addr->v6.sin6_addr;
 443         }
 444 }
 445
 446 /* Initialize sk->sk_daddr from sctp_addr. */
 447 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
 448 {
 449         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
 450                 inet6_sk(sk)->daddr.s6_addr32[0] = 0;
 451                 inet6_sk(sk)->daddr.s6_addr32[1] = 0;
 452                 inet6_sk(sk)->daddr.s6_addr32[2] = htonl(0x0000ffff);
 453                 inet6_sk(sk)->daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
 454         } else {
 455                 inet6_sk(sk)->daddr = addr->v6.sin6_addr;
 456         }
 457 }
 458
 459 /* Initialize a sctp_addr from an address parameter. */
 460 static void sctp_v6_from_addr_param(union sctp_addr *addr,
 461                                     union sctp_addr_param *param,
 462                                     __be16 port, int iif)
 463 {
 464         addr->v6.sin6_family = AF_INET6;
 465         addr->v6.sin6_port = port;
 466         addr->v6.sin6_flowinfo = 0; /* BUG */
 467         addr->v6.sin6_addr = param->v6.addr;
 468         addr->v6.sin6_scope_id = iif;
 469 }
 470
 471 /* Initialize an address parameter from a sctp_addr and return the length
 472  * of the address parameter.
 473  */
 474 static int sctp_v6_to_addr_param(const union sctp_addr *addr,
 475                                  union sctp_addr_param *param)
 476 {
 477         int length = sizeof(sctp_ipv6addr_param_t);
 478
 479         param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
 480         param->v6.param_hdr.length = htons(length);
 481         param->v6.addr = addr->v6.sin6_addr;
 482
 483         return length;
 484 }
 485
 486 /* Initialize a sctp_addr from struct in6_addr. */
 487 static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr,
 488                               __be16 port)
 489 {
 490         addr->sa.sa_family = AF_INET6;
 491         addr->v6.sin6_port = port;
 492         addr->v6.sin6_addr = *saddr;
 493 }
 494
 495 /* Compare addresses exactly.
 496  * v4-mapped-v6 is also in consideration.
 497  */
 498 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
 499                             const union sctp_addr *addr2)
 500 {
 501         if (addr1->sa.sa_family != addr2->sa.sa_family) {
 502                 if (addr1->sa.sa_family == AF_INET &&
 503                     addr2->sa.sa_family == AF_INET6 &&
 504                     ipv6_addr_v4mapped(&addr2->v6.sin6_addr)) {
 505                         if (addr2->v6.sin6_port == addr1->v4.sin_port &&
 506                             addr2->v6.sin6_addr.s6_addr32[3] ==
 507                             addr1->v4.sin_addr.s_addr)
 508                                 return 1;
 509                 }
 510                 if (addr2->sa.sa_family == AF_INET &&
 511                     addr1->sa.sa_family == AF_INET6 &&
 512                     ipv6_addr_v4mapped(&addr1->v6.sin6_addr)) {
 513                         if (addr1->v6.sin6_port == addr2->v4.sin_port &&
 514                             addr1->v6.sin6_addr.s6_addr32[3] ==
 515                             addr2->v4.sin_addr.s_addr)
 516                                 return 1;
 517                 }
 518                 return 0;
 519         }
 520         if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
 521                 return 0;
 522         /* If this is a linklocal address, compare the scope_id. */
 523         if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) {
 524                 if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
 525                     (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) {
 526                         return 0;
 527                 }
 528         }
 529
 530         return 1;
 531 }
 532
 533 /* Initialize addr struct to INADDR_ANY. */
 534 static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port)
 535 {
 536         memset(addr, 0x00, sizeof(union sctp_addr));
 537         addr->v6.sin6_family = AF_INET6;
 538         addr->v6.sin6_port = port;
 539 }
 540
 541 /* Is this a wildcard address? */
 542 static int sctp_v6_is_any(const union sctp_addr *addr)
 543 {
 544         return ipv6_addr_any(&addr->v6.sin6_addr);
 545 }
 546
 547 /* Should this be available for binding?   */
 548 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
 549 {
 550         int type;
 551         const struct in6_addr *in6 = (const struct in6_addr *)&addr->v6.sin6_addr;
 552
 553         type = ipv6_addr_type(in6);
 554         if (IPV6_ADDR_ANY == type)
 555                 return 1;
 556         if (type == IPV6_ADDR_MAPPED) {
 557                 if (sp && !sp->v4mapped)
 558                         return 0;
 559                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
 560                         return 0;
 561                 sctp_v6_map_v4(addr);
 562                 return sctp_get_af_specific(AF_INET)->available(addr, sp);
 563         }
 564         if (!(type & IPV6_ADDR_UNICAST))
 565                 return 0;
 566
 567         return ipv6_chk_addr(sock_net(&sp->inet.sk), in6, NULL, 0);
 568 }
 569
 570 /* This function checks if the address is a valid address to be used for
 571  * SCTP.
 572  *
 573  * Output:
 574  * Return 0 - If the address is a non-unicast or an illegal address.
 575  * Return 1 - If the address is a unicast.
 576  */
 577 static int sctp_v6_addr_valid(union sctp_addr *addr,
 578                               struct sctp_sock *sp,
 579                               const struct sk_buff *skb)
 580 {
 581         int ret = ipv6_addr_type(&addr->v6.sin6_addr);
 582
 583         /* Support v4-mapped-v6 address. */
 584         if (ret == IPV6_ADDR_MAPPED) {
 585                 /* Note: This routine is used in input, so v4-mapped-v6
 586                  * are disallowed here when there is no sctp_sock.
 587                  */
 588                 if (!sp || !sp->v4mapped)
 589                         return 0;
 590                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
 591                         return 0;
 592                 sctp_v6_map_v4(addr);
 593                 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb);
 594         }
 595
 596         /* Is this a non-unicast address */
 597         if (!(ret & IPV6_ADDR_UNICAST))
 598                 return 0;
 599
 600         return 1;
 601 }
 602
 603 /* What is the scope of 'addr'?  */
 604 static sctp_scope_t sctp_v6_scope(union sctp_addr *addr)
 605 {
 606         int v6scope;
 607         sctp_scope_t retval;
 608
 609         /* The IPv6 scope is really a set of bit fields.
 610          * See IFA_* in <net/if_inet6.h>.  Map to a generic SCTP scope.
 611          */
 612
 613         v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
 614         switch (v6scope) {
 615         case IFA_HOST:
 616                 retval = SCTP_SCOPE_LOOPBACK;
 617                 break;
 618         case IFA_LINK:
 619                 retval = SCTP_SCOPE_LINK;
 620                 break;
 621         case IFA_SITE:
 622                 retval = SCTP_SCOPE_PRIVATE;
 623                 break;
 624         default:
 625                 retval = SCTP_SCOPE_GLOBAL;
 626                 break;
 627         }
 628
 629         return retval;
 630 }
 631
 632 /* Create and initialize a new sk for the socket to be returned by accept(). */
 633 static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
 634                                              struct sctp_association *asoc)
 635 {
 636         struct sock *newsk;
 637         struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
 638         struct sctp6_sock *newsctp6sk;
 639
 640         newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot);
 641         if (!newsk)
 642                 goto out;
 643
 644         sock_init_data(NULL, newsk);
 645
 646         sctp_copy_sock(newsk, sk, asoc);
 647         sock_reset_flag(sk, SOCK_ZAPPED);
 648
 649         newsctp6sk = (struct sctp6_sock *)newsk;
 650         inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
 651
 652         sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped;
 653
 654         newnp = inet6_sk(newsk);
 655
 656         memcpy(newnp, np, sizeof(struct ipv6_pinfo));
 657
 658         /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
 659          * and getpeername().
 660          */
 661         sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
 662
 663         sk_refcnt_debug_inc(newsk);
 664
 665         if (newsk->sk_prot->init(newsk)) {
 666                 sk_common_release(newsk);
 667                 newsk = NULL;
 668         }
 669
 670 out:
 671         return newsk;
 672 }
 673
 674 /* Map v4 address to mapped v6 address */
 675 static void sctp_v6_addr_v4map(struct sctp_sock *sp, union sctp_addr *addr)
 676 {
 677         if (sp->v4mapped && AF_INET == addr->sa.sa_family)
 678                 sctp_v4_map_v6(addr);
 679 }
 680
 681 /* Where did this skb come from?  */
 682 static int sctp_v6_skb_iif(const struct sk_buff *skb)
 683 {
 684         struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb;
 685         return opt->iif;
 686 }
 687
 688 /* Was this packet marked by Explicit Congestion Notification? */
 689 static int sctp_v6_is_ce(const struct sk_buff *skb)
 690 {
 691         return *((__u32 *)(ipv6_hdr(skb))) & htonl(1 << 20);
 692 }
 693
 694 /* Dump the v6 addr to the seq file. */
 695 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
 696 {
 697         seq_printf(seq, "%pI6 ", &addr->v6.sin6_addr);
 698 }
 699
 700 static void sctp_v6_ecn_capable(struct sock *sk)
 701 {
 702         inet6_sk(sk)->tclass |= INET_ECN_ECT_0;
 703 }
 704
 705 /* Initialize a PF_INET6 socket msg_name. */
 706 static void sctp_inet6_msgname(char *msgname, int *addr_len)
 707 {
 708         struct sockaddr_in6 *sin6;
 709
 710         sin6 = (struct sockaddr_in6 *)msgname;
 711         sin6->sin6_family = AF_INET6;
 712         sin6->sin6_flowinfo = 0;
 713         sin6->sin6_scope_id = 0; /*FIXME */
 714         *addr_len = sizeof(struct sockaddr_in6);
 715 }
 716
 717 /* Initialize a PF_INET msgname from a ulpevent. */
 718 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
 719                                      char *msgname, int *addrlen)
 720 {
 721         struct sockaddr_in6 *sin6, *sin6from;
 722
 723         if (msgname) {
 724                 union sctp_addr *addr;
 725                 struct sctp_association *asoc;
 726
 727                 asoc = event->asoc;
 728                 sctp_inet6_msgname(msgname, addrlen);
 729                 sin6 = (struct sockaddr_in6 *)msgname;
 730                 sin6->sin6_port = htons(asoc->peer.port);
 731                 addr = &asoc->peer.primary_addr;
 732
 733                 /* Note: If we go to a common v6 format, this code
 734                  * will change.
 735                  */
 736
 737                 /* Map ipv4 address into v4-mapped-on-v6 address.  */
 738                 if (sctp_sk(asoc->base.sk)->v4mapped &&
 739                     AF_INET == addr->sa.sa_family) {
 740                         sctp_v4_map_v6((union sctp_addr *)sin6);
 741                         sin6->sin6_addr.s6_addr32[3] =
 742                                 addr->v4.sin_addr.s_addr;
 743                         return;
 744                 }
 745
 746                 sin6from = &asoc->peer.primary_addr.v6;
 747                 sin6->sin6_addr = sin6from->sin6_addr;
 748                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 749                         sin6->sin6_scope_id = sin6from->sin6_scope_id;
 750         }
 751 }
 752
 753 /* Initialize a msg_name from an inbound skb. */
 754 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
 755                                    int *addr_len)
 756 {
 757         struct sctphdr *sh;
 758         struct sockaddr_in6 *sin6;
 759
 760         if (msgname) {
 761                 sctp_inet6_msgname(msgname, addr_len);
 762                 sin6 = (struct sockaddr_in6 *)msgname;
 763                 sh = sctp_hdr(skb);
 764                 sin6->sin6_port = sh->source;
 765
 766                 /* Map ipv4 address into v4-mapped-on-v6 address. */
 767                 if (sctp_sk(skb->sk)->v4mapped &&
 768                     ip_hdr(skb)->version == 4) {
 769                         sctp_v4_map_v6((union sctp_addr *)sin6);
 770                         sin6->sin6_addr.s6_addr32[3] = ip_hdr(skb)->saddr;
 771                         return;
 772                 }
 773
 774                 /* Otherwise, just copy the v6 address. */
 775                 sin6->sin6_addr = ipv6_hdr(skb)->saddr;
 776                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) {
 777                         struct sctp_ulpevent *ev = sctp_skb2event(skb);
 778                         sin6->sin6_scope_id = ev->iif;
 779                 }
 780         }
 781 }
 782
 783 /* Do we support this AF? */
 784 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
 785 {
 786         switch (family) {
 787         case AF_INET6:
 788                 return 1;
 789         /* v4-mapped-v6 addresses */
 790         case AF_INET:
 791                 if (!__ipv6_only_sock(sctp_opt2sk(sp)))
 792                         return 1;
 793         default:
 794                 return 0;
 795         }
 796 }
 797
 798 /* Address matching with wildcards allowed.  This extra level
 799  * of indirection lets us choose whether a PF_INET6 should
 800  * disallow any v4 addresses if we so choose.
 801  */
 802 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
 803                                const union sctp_addr *addr2,
 804                                struct sctp_sock *opt)
 805 {
 806         struct sctp_af *af1, *af2;
 807         struct sock *sk = sctp_opt2sk(opt);
 808
 809         af1 = sctp_get_af_specific(addr1->sa.sa_family);
 810         af2 = sctp_get_af_specific(addr2->sa.sa_family);
 811
 812         if (!af1 || !af2)
 813                 return 0;
 814
 815         /* If the socket is IPv6 only, v4 addrs will not match */
 816         if (__ipv6_only_sock(sk) && af1 != af2)
 817                 return 0;
 818
 819         /* Today, wildcard AF_INET/AF_INET6. */
 820         if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2))
 821                 return 1;
 822
 823         if (addr1->sa.sa_family != addr2->sa.sa_family)
 824                 return 0;
 825
 826         return af1->cmp_addr(addr1, addr2);
 827 }
 828
 829 /* Verify that the provided sockaddr looks bindable.   Common verification,
 830  * has already been taken care of.
 831  */
 832 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
 833 {
 834         struct sctp_af *af;
 835
 836         /* ASSERT: address family has already been verified. */
 837         if (addr->sa.sa_family != AF_INET6)
 838                 af = sctp_get_af_specific(addr->sa.sa_family);
 839         else {
 840                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
 841                 struct net_device *dev;
 842
 843                 if (type & IPV6_ADDR_LINKLOCAL) {
 844                         struct net *net;
 845                         if (!addr->v6.sin6_scope_id)
 846                                 return 0;
 847                         net = sock_net(&opt->inet.sk);
 848                         rcu_read_lock();
 849                         dev = dev_get_by_index_rcu(net, addr->v6.sin6_scope_id);
 850                         if (!dev ||
 851                             !ipv6_chk_addr(net, &addr->v6.sin6_addr, dev, 0)) {
 852                                 rcu_read_unlock();
 853                                 return 0;
 854                         }
 855                         rcu_read_unlock();
 856                 } else if (type == IPV6_ADDR_MAPPED) {
 857                         if (!opt->v4mapped)
 858                                 return 0;
 859                 }
 860
 861                 af = opt->pf->af;
 862         }
 863         return af->available(addr, opt);
 864 }
 865
 866 /* Verify that the provided sockaddr looks sendable.   Common verification,
 867  * has already been taken care of.
 868  */
 869 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
 870 {
 871         struct sctp_af *af = NULL;
 872
 873         /* ASSERT: address family has already been verified. */
 874         if (addr->sa.sa_family != AF_INET6)
 875                 af = sctp_get_af_specific(addr->sa.sa_family);
 876         else {
 877                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
 878                 struct net_device *dev;
 879
 880                 if (type & IPV6_ADDR_LINKLOCAL) {
 881                         if (!addr->v6.sin6_scope_id)
 882                                 return 0;
 883                         rcu_read_lock();
 884                         dev = dev_get_by_index_rcu(sock_net(&opt->inet.sk),
 885                                                    addr->v6.sin6_scope_id);
 886                         rcu_read_unlock();
 887                         if (!dev)
 888                                 return 0;
 889                 }
 890                 af = opt->pf->af;
 891         }
 892
 893         return af != NULL;
 894 }
 895
 896 /* Fill in Supported Address Type information for INIT and INIT-ACK
 897  * chunks.   Note: In the future, we may want to look at sock options
 898  * to determine whether a PF_INET6 socket really wants to have IPV4
 899  * addresses.
 900  * Returns number of addresses supported.
 901  */
 902 static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
 903                                       __be16 *types)
 904 {
 905         types[0] = SCTP_PARAM_IPV6_ADDRESS;
 906         if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) {
 907                 types[1] = SCTP_PARAM_IPV4_ADDRESS;
 908                 return 2;
 909         }
 910         return 1;
 911 }
 912
 913 static const struct proto_ops inet6_seqpacket_ops = {
 914         .family            = PF_INET6,
 915         .owner             = THIS_MODULE,
 916         .release           = inet6_release,
 917         .bind              = inet6_bind,
 918         .connect           = inet_dgram_connect,
 919         .socketpair        = sock_no_socketpair,
 920         .accept            = inet_accept,
 921         .getname           = inet6_getname,
 922         .poll              = sctp_poll,
 923         .ioctl             = inet6_ioctl,
 924         .listen            = sctp_inet_listen,
 925         .shutdown          = inet_shutdown,
 926         .setsockopt        = sock_common_setsockopt,
 927         .getsockopt        = sock_common_getsockopt,
 928         .sendmsg           = inet_sendmsg,
 929         .recvmsg           = sock_common_recvmsg,
 930         .mmap              = sock_no_mmap,
 931 #ifdef CONFIG_COMPAT
 932         .compat_setsockopt = compat_sock_common_setsockopt,
 933         .compat_getsockopt = compat_sock_common_getsockopt,
 934 #endif
 935 };
 936
 937 static struct inet_protosw sctpv6_seqpacket_protosw = {
 938         .type          = SOCK_SEQPACKET,
 939         .protocol      = IPPROTO_SCTP,
 940         .prot          = &sctpv6_prot,
 941         .ops           = &inet6_seqpacket_ops,
 942         .no_check      = 0,
 943         .flags         = SCTP_PROTOSW_FLAG
 944 };
 945 static struct inet_protosw sctpv6_stream_protosw = {
 946         .type          = SOCK_STREAM,
 947         .protocol      = IPPROTO_SCTP,
 948         .prot          = &sctpv6_prot,
 949         .ops           = &inet6_seqpacket_ops,
 950         .no_check      = 0,
 951         .flags         = SCTP_PROTOSW_FLAG,
 952 };
 953
 954 static int sctp6_rcv(struct sk_buff *skb)
 955 {
 956         return sctp_rcv(skb) ? -1 : 0;
 957 }
 958
 959 static const struct inet6_protocol sctpv6_protocol = {
 960         .handler      = sctp6_rcv,
 961         .err_handler  = sctp_v6_err,
 962         .flags        = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
 963 };
 964
 965 static struct sctp_af sctp_af_inet6 = {
 966         .sa_family         = AF_INET6,
 967         .sctp_xmit         = sctp_v6_xmit,
 968         .setsockopt        = ipv6_setsockopt,
 969         .getsockopt        = ipv6_getsockopt,
 970         .get_dst           = sctp_v6_get_dst,
 971         .get_saddr         = sctp_v6_get_saddr,
 972         .copy_addrlist     = sctp_v6_copy_addrlist,
 973         .from_skb          = sctp_v6_from_skb,
 974         .from_sk           = sctp_v6_from_sk,
 975         .to_sk_saddr       = sctp_v6_to_sk_saddr,
 976         .to_sk_daddr       = sctp_v6_to_sk_daddr,
 977         .from_addr_param   = sctp_v6_from_addr_param,
 978         .to_addr_param     = sctp_v6_to_addr_param,
 979         .cmp_addr          = sctp_v6_cmp_addr,
 980         .scope             = sctp_v6_scope,
 981         .addr_valid        = sctp_v6_addr_valid,
 982         .inaddr_any        = sctp_v6_inaddr_any,
 983         .is_any            = sctp_v6_is_any,
 984         .available         = sctp_v6_available,
 985         .skb_iif           = sctp_v6_skb_iif,
 986         .is_ce             = sctp_v6_is_ce,
 987         .seq_dump_addr     = sctp_v6_seq_dump_addr,
 988         .ecn_capable       = sctp_v6_ecn_capable,
 989         .net_header_len    = sizeof(struct ipv6hdr),
 990         .sockaddr_len      = sizeof(struct sockaddr_in6),
 991 #ifdef CONFIG_COMPAT
 992         .compat_setsockopt = compat_ipv6_setsockopt,
 993         .compat_getsockopt = compat_ipv6_getsockopt,
 994 #endif
 995 };
 996
 997 static struct sctp_pf sctp_pf_inet6 = {
 998         .event_msgname = sctp_inet6_event_msgname,
 999         .skb_msgname   = sctp_inet6_skb_msgname,
1000         .af_supported  = sctp_inet6_af_supported,
1001         .cmp_addr      = sctp_inet6_cmp_addr,
1002         .bind_verify   = sctp_inet6_bind_verify,
1003         .send_verify   = sctp_inet6_send_verify,
1004         .supported_addrs = sctp_inet6_supported_addrs,
1005         .create_accept_sk = sctp_v6_create_accept_sk,
1006         .addr_v4map    = sctp_v6_addr_v4map,
1007         .af            = &sctp_af_inet6,
1008 };
1009
1010 /* Initialize IPv6 support and register with socket layer.  */
1011 void sctp_v6_pf_init(void)
1012 {
1013         /* Register the SCTP specific PF_INET6 functions. */
1014         sctp_register_pf(&sctp_pf_inet6, PF_INET6);
1015
1016         /* Register the SCTP specific AF_INET6 functions. */
1017         sctp_register_af(&sctp_af_inet6);
1018 }
1019
1020 void sctp_v6_pf_exit(void)
1021 {
1022         list_del(&sctp_af_inet6.list);
1023 }
1024
1025 /* Initialize IPv6 support and register with socket layer.  */
1026 int sctp_v6_protosw_init(void)
1027 {
1028         int rc;
1029
1030         rc = proto_register(&sctpv6_prot, 1);
1031         if (rc)
1032                 return rc;
1033
1034         /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
1035         inet6_register_protosw(&sctpv6_seqpacket_protosw);
1036         inet6_register_protosw(&sctpv6_stream_protosw);
1037
1038         return 0;
1039 }
1040
1041 void sctp_v6_protosw_exit(void)
1042 {
1043         inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
1044         inet6_unregister_protosw(&sctpv6_stream_protosw);
1045         proto_unregister(&sctpv6_prot);
1046 }
1047
1048
1049 /* Register with inet6 layer. */
1050 int sctp_v6_add_protocol(void)
1051 {
1052         /* Register notifier for inet6 address additions/deletions. */
1053         register_inet6addr_notifier(&sctp_inet6addr_notifier);
1054
1055         if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
1056                 return -EAGAIN;
1057
1058         return 0;
1059 }
1060
1061 /* Unregister with inet6 layer. */
1062 void sctp_v6_del_protocol(void)
1063 {
1064         inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
1065         unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1066 }