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   1 /* SCTP kernel reference 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 reference Implementation
   8  *
   9  * SCTP over IPv6.
  10  *
  11  * The SCTP reference 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  * The SCTP reference 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 #include <linux/module.h>
  51 #include <linux/errno.h>
  52 #include <linux/types.h>
  53 #include <linux/socket.h>
  54 #include <linux/sockios.h>
  55 #include <linux/net.h>
  56 #include <linux/in.h>
  57 #include <linux/in6.h>
  58 #include <linux/netdevice.h>
  59 #include <linux/init.h>
  60 #include <linux/ipsec.h>
  61
  62 #include <linux/ipv6.h>
  63 #include <linux/icmpv6.h>
  64 #include <linux/random.h>
  65 #include <linux/seq_file.h>
  66
  67 #include <net/protocol.h>
  68 #include <net/ndisc.h>
  69 #include <net/ip.h>
  70 #include <net/ipv6.h>
  71 #include <net/transp_v6.h>
  72 #include <net/addrconf.h>
  73 #include <net/ip6_route.h>
  74 #include <net/inet_common.h>
  75 #include <net/inet_ecn.h>
  76 #include <net/sctp/sctp.h>
  77
  78 #include <asm/uaccess.h>
  79
  80 /* Event handler for inet6 address addition/deletion events.  */
  81 static int sctp_inet6addr_event(struct notifier_block *this, unsigned long ev,
  82                                 void *ptr)
  83 {
  84         struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
  85         struct sctp_sockaddr_entry *addr;
  86         struct list_head *pos, *temp;
  87
  88         switch (ev) {
  89         case NETDEV_UP:
  90                 addr = kmalloc(sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC);
  91                 if (addr) {
  92                         addr->a.v6.sin6_family = AF_INET6;
  93                         addr->a.v6.sin6_port = 0;
  94                         memcpy(&addr->a.v6.sin6_addr, &ifa->addr,
  95                                  sizeof(struct in6_addr));
  96                         addr->a.v6.sin6_scope_id = ifa->idev->dev->ifindex;
  97                         list_add_tail(&addr->list, &sctp_local_addr_list);
  98                 }
  99                 break;
 100         case NETDEV_DOWN:
 101                 list_for_each_safe(pos, temp, &sctp_local_addr_list) {
 102                         addr = list_entry(pos, struct sctp_sockaddr_entry, list);
 103                         if (ipv6_addr_equal(&addr->a.v6.sin6_addr, &ifa->addr)) {
 104                                 list_del(pos);
 105                                 kfree(addr);
 106                                 break;
 107                         }
 108                 }
 109
 110                 break;
 111         }
 112
 113         return NOTIFY_DONE;
 114 }
 115
 116 static struct notifier_block sctp_inet6addr_notifier = {
 117         .notifier_call = sctp_inet6addr_event,
 118 };
 119
 120 /* ICMP error handler. */
 121 SCTP_STATIC void sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 122                              int type, int code, int offset, __be32 info)
 123 {
 124         struct inet6_dev *idev;
 125         struct sock *sk;
 126         struct sctp_association *asoc;
 127         struct sctp_transport *transport;
 128         struct ipv6_pinfo *np;
 129         sk_buff_data_t saveip, savesctp;
 130         int err;
 131
 132         idev = in6_dev_get(skb->dev);
 133
 134         /* Fix up skb to look at the embedded net header. */
 135         saveip   = skb->network_header;
 136         savesctp = skb->transport_header;
 137         skb_reset_network_header(skb);
 138         skb_set_transport_header(skb, offset);
 139         sk = sctp_err_lookup(AF_INET6, skb, sctp_hdr(skb), &asoc, &transport);
 140         /* Put back, the original pointers. */
 141         skb->network_header   = saveip;
 142         skb->transport_header = savesctp;
 143         if (!sk) {
 144                 ICMP6_INC_STATS_BH(idev, ICMP6_MIB_INERRORS);
 145                 goto out;
 146         }
 147
 148         /* Warning:  The sock lock is held.  Remember to call
 149          * sctp_err_finish!
 150          */
 151
 152         switch (type) {
 153         case ICMPV6_PKT_TOOBIG:
 154                 sctp_icmp_frag_needed(sk, asoc, transport, ntohl(info));
 155                 goto out_unlock;
 156         case ICMPV6_PARAMPROB:
 157                 if (ICMPV6_UNK_NEXTHDR == code) {
 158                         sctp_icmp_proto_unreachable(sk, asoc, transport);
 159                         goto out_unlock;
 160                 }
 161                 break;
 162         default:
 163                 break;
 164         }
 165
 166         np = inet6_sk(sk);
 167         icmpv6_err_convert(type, code, &err);
 168         if (!sock_owned_by_user(sk) && np->recverr) {
 169                 sk->sk_err = err;
 170                 sk->sk_error_report(sk);
 171         } else {  /* Only an error on timeout */
 172                 sk->sk_err_soft = err;
 173         }
 174
 175 out_unlock:
 176         sctp_err_finish(sk, asoc);
 177 out:
 178         if (likely(idev != NULL))
 179                 in6_dev_put(idev);
 180 }
 181
 182 /* Based on tcp_v6_xmit() in tcp_ipv6.c. */
 183 static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *transport,
 184                         int ipfragok)
 185 {
 186         struct sock *sk = skb->sk;
 187         struct ipv6_pinfo *np = inet6_sk(sk);
 188         struct flowi fl;
 189
 190         memset(&fl, 0, sizeof(fl));
 191
 192         fl.proto = sk->sk_protocol;
 193
 194         /* Fill in the dest address from the route entry passed with the skb
 195          * and the source address from the transport.
 196          */
 197         ipv6_addr_copy(&fl.fl6_dst, &transport->ipaddr.v6.sin6_addr);
 198         ipv6_addr_copy(&fl.fl6_src, &transport->saddr.v6.sin6_addr);
 199
 200         fl.fl6_flowlabel = np->flow_label;
 201         IP6_ECN_flow_xmit(sk, fl.fl6_flowlabel);
 202         if (ipv6_addr_type(&fl.fl6_src) & IPV6_ADDR_LINKLOCAL)
 203                 fl.oif = transport->saddr.v6.sin6_scope_id;
 204         else
 205                 fl.oif = sk->sk_bound_dev_if;
 206
 207         if (np->opt && np->opt->srcrt) {
 208                 struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
 209                 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
 210         }
 211
 212         SCTP_DEBUG_PRINTK("%s: skb:%p, len:%d, "
 213                           "src:" NIP6_FMT " dst:" NIP6_FMT "\n",
 214                           __FUNCTION__, skb, skb->len,
 215                           NIP6(fl.fl6_src), NIP6(fl.fl6_dst));
 216
 217         SCTP_INC_STATS(SCTP_MIB_OUTSCTPPACKS);
 218
 219         return ip6_xmit(sk, skb, &fl, np->opt, ipfragok);
 220 }
 221
 222 /* Returns the dst cache entry for the given source and destination ip
 223  * addresses.
 224  */
 225 static struct dst_entry *sctp_v6_get_dst(struct sctp_association *asoc,
 226                                          union sctp_addr *daddr,
 227                                          union sctp_addr *saddr)
 228 {
 229         struct dst_entry *dst;
 230         struct flowi fl;
 231
 232         memset(&fl, 0, sizeof(fl));
 233         ipv6_addr_copy(&fl.fl6_dst, &daddr->v6.sin6_addr);
 234         if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
 235                 fl.oif = daddr->v6.sin6_scope_id;
 236
 237
 238         SCTP_DEBUG_PRINTK("%s: DST=" NIP6_FMT " ",
 239                           __FUNCTION__, NIP6(fl.fl6_dst));
 240
 241         if (saddr) {
 242                 ipv6_addr_copy(&fl.fl6_src, &saddr->v6.sin6_addr);
 243                 SCTP_DEBUG_PRINTK(
 244                         "SRC=" NIP6_FMT " - ",
 245                         NIP6(fl.fl6_src));
 246         }
 247
 248         dst = ip6_route_output(NULL, &fl);
 249         if (!dst->error) {
 250                 struct rt6_info *rt;
 251                 rt = (struct rt6_info *)dst;
 252                 SCTP_DEBUG_PRINTK(
 253                         "rt6_dst:" NIP6_FMT " rt6_src:" NIP6_FMT "\n",
 254                         NIP6(rt->rt6i_dst.addr), NIP6(rt->rt6i_src.addr));
 255                 return dst;
 256         }
 257         SCTP_DEBUG_PRINTK("NO ROUTE\n");
 258         dst_release(dst);
 259         return NULL;
 260 }
 261
 262 /* Returns the number of consecutive initial bits that match in the 2 ipv6
 263  * addresses.
 264  */
 265 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
 266                                          union sctp_addr *s2)
 267 {
 268         struct in6_addr *a1 = &s1->v6.sin6_addr;
 269         struct in6_addr *a2 = &s2->v6.sin6_addr;
 270         int i, j;
 271
 272         for (i = 0; i < 4 ; i++) {
 273                 __be32 a1xora2;
 274
 275                 a1xora2 = a1->s6_addr32[i] ^ a2->s6_addr32[i];
 276
 277                 if ((j = fls(ntohl(a1xora2))))
 278                         return (i * 32 + 32 - j);
 279         }
 280
 281         return (i*32);
 282 }
 283
 284 /* Fills in the source address(saddr) based on the destination address(daddr)
 285  * and asoc's bind address list.
 286  */
 287 static void sctp_v6_get_saddr(struct sctp_association *asoc,
 288                               struct dst_entry *dst,
 289                               union sctp_addr *daddr,
 290                               union sctp_addr *saddr)
 291 {
 292         struct sctp_bind_addr *bp;
 293         rwlock_t *addr_lock;
 294         struct sctp_sockaddr_entry *laddr;
 295         struct list_head *pos;
 296         sctp_scope_t scope;
 297         union sctp_addr *baddr = NULL;
 298         __u8 matchlen = 0;
 299         __u8 bmatchlen;
 300
 301         SCTP_DEBUG_PRINTK("%s: asoc:%p dst:%p "
 302                           "daddr:" NIP6_FMT " ",
 303                           __FUNCTION__, asoc, dst, NIP6(daddr->v6.sin6_addr));
 304
 305         if (!asoc) {
 306                 ipv6_get_saddr(dst, &daddr->v6.sin6_addr,&saddr->v6.sin6_addr);
 307                 SCTP_DEBUG_PRINTK("saddr from ipv6_get_saddr: " NIP6_FMT "\n",
 308                                   NIP6(saddr->v6.sin6_addr));
 309                 return;
 310         }
 311
 312         scope = sctp_scope(daddr);
 313
 314         bp = &asoc->base.bind_addr;
 315         addr_lock = &asoc->base.addr_lock;
 316
 317         /* Go through the bind address list and find the best source address
 318          * that matches the scope of the destination address.
 319          */
 320         sctp_read_lock(addr_lock);
 321         list_for_each(pos, &bp->address_list) {
 322                 laddr = list_entry(pos, struct sctp_sockaddr_entry, list);
 323                 if ((laddr->use_as_src) &&
 324                     (laddr->a.sa.sa_family == AF_INET6) &&
 325                     (scope <= sctp_scope(&laddr->a))) {
 326                         bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
 327                         if (!baddr || (matchlen < bmatchlen)) {
 328                                 baddr = &laddr->a;
 329                                 matchlen = bmatchlen;
 330                         }
 331                 }
 332         }
 333
 334         if (baddr) {
 335                 memcpy(saddr, baddr, sizeof(union sctp_addr));
 336                 SCTP_DEBUG_PRINTK("saddr: " NIP6_FMT "\n",
 337                                   NIP6(saddr->v6.sin6_addr));
 338         } else {
 339                 printk(KERN_ERR "%s: asoc:%p Could not find a valid source "
 340                        "address for the dest:" NIP6_FMT "\n",
 341                        __FUNCTION__, asoc, NIP6(daddr->v6.sin6_addr));
 342         }
 343
 344         sctp_read_unlock(addr_lock);
 345 }
 346
 347 /* Make a copy of all potential local addresses. */
 348 static void sctp_v6_copy_addrlist(struct list_head *addrlist,
 349                                   struct net_device *dev)
 350 {
 351         struct inet6_dev *in6_dev;
 352         struct inet6_ifaddr *ifp;
 353         struct sctp_sockaddr_entry *addr;
 354
 355         rcu_read_lock();
 356         if ((in6_dev = __in6_dev_get(dev)) == NULL) {
 357                 rcu_read_unlock();
 358                 return;
 359         }
 360
 361         read_lock_bh(&in6_dev->lock);
 362         for (ifp = in6_dev->addr_list; ifp; ifp = ifp->if_next) {
 363                 /* Add the address to the local list.  */
 364                 addr = t_new(struct sctp_sockaddr_entry, GFP_ATOMIC);
 365                 if (addr) {
 366                         addr->a.v6.sin6_family = AF_INET6;
 367                         addr->a.v6.sin6_port = 0;
 368                         addr->a.v6.sin6_addr = ifp->addr;
 369                         addr->a.v6.sin6_scope_id = dev->ifindex;
 370                         INIT_LIST_HEAD(&addr->list);
 371                         list_add_tail(&addr->list, addrlist);
 372                 }
 373         }
 374
 375         read_unlock_bh(&in6_dev->lock);
 376         rcu_read_unlock();
 377 }
 378
 379 /* Initialize a sockaddr_storage from in incoming skb. */
 380 static void sctp_v6_from_skb(union sctp_addr *addr,struct sk_buff *skb,
 381                              int is_saddr)
 382 {
 383         void *from;
 384         __be16 *port;
 385         struct sctphdr *sh;
 386
 387         port = &addr->v6.sin6_port;
 388         addr->v6.sin6_family = AF_INET6;
 389         addr->v6.sin6_flowinfo = 0; /* FIXME */
 390         addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif;
 391
 392         sh = sctp_hdr(skb);
 393         if (is_saddr) {
 394                 *port  = sh->source;
 395                 from = &ipv6_hdr(skb)->saddr;
 396         } else {
 397                 *port = sh->dest;
 398                 from = &ipv6_hdr(skb)->daddr;
 399         }
 400         ipv6_addr_copy(&addr->v6.sin6_addr, from);
 401 }
 402
 403 /* Initialize an sctp_addr from a socket. */
 404 static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
 405 {
 406         addr->v6.sin6_family = AF_INET6;
 407         addr->v6.sin6_port = 0;
 408         addr->v6.sin6_addr = inet6_sk(sk)->rcv_saddr;
 409 }
 410
 411 /* Initialize sk->sk_rcv_saddr from sctp_addr. */
 412 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
 413 {
 414         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
 415                 inet6_sk(sk)->rcv_saddr.s6_addr32[0] = 0;
 416                 inet6_sk(sk)->rcv_saddr.s6_addr32[1] = 0;
 417                 inet6_sk(sk)->rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
 418                 inet6_sk(sk)->rcv_saddr.s6_addr32[3] =
 419                         addr->v4.sin_addr.s_addr;
 420         } else {
 421                 inet6_sk(sk)->rcv_saddr = addr->v6.sin6_addr;
 422         }
 423 }
 424
 425 /* Initialize sk->sk_daddr from sctp_addr. */
 426 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
 427 {
 428         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
 429                 inet6_sk(sk)->daddr.s6_addr32[0] = 0;
 430                 inet6_sk(sk)->daddr.s6_addr32[1] = 0;
 431                 inet6_sk(sk)->daddr.s6_addr32[2] = htonl(0x0000ffff);
 432                 inet6_sk(sk)->daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
 433         } else {
 434                 inet6_sk(sk)->daddr = addr->v6.sin6_addr;
 435         }
 436 }
 437
 438 /* Initialize a sctp_addr from an address parameter. */
 439 static void sctp_v6_from_addr_param(union sctp_addr *addr,
 440                                     union sctp_addr_param *param,
 441                                     __be16 port, int iif)
 442 {
 443         addr->v6.sin6_family = AF_INET6;
 444         addr->v6.sin6_port = port;
 445         addr->v6.sin6_flowinfo = 0; /* BUG */
 446         ipv6_addr_copy(&addr->v6.sin6_addr, &param->v6.addr);
 447         addr->v6.sin6_scope_id = iif;
 448 }
 449
 450 /* Initialize an address parameter from a sctp_addr and return the length
 451  * of the address parameter.
 452  */
 453 static int sctp_v6_to_addr_param(const union sctp_addr *addr,
 454                                  union sctp_addr_param *param)
 455 {
 456         int length = sizeof(sctp_ipv6addr_param_t);
 457
 458         param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
 459         param->v6.param_hdr.length = htons(length);
 460         ipv6_addr_copy(&param->v6.addr, &addr->v6.sin6_addr);
 461
 462         return length;
 463 }
 464
 465 /* Initialize a sctp_addr from a dst_entry. */
 466 static void sctp_v6_dst_saddr(union sctp_addr *addr, struct dst_entry *dst,
 467                               __be16 port)
 468 {
 469         struct rt6_info *rt = (struct rt6_info *)dst;
 470         addr->sa.sa_family = AF_INET6;
 471         addr->v6.sin6_port = port;
 472         ipv6_addr_copy(&addr->v6.sin6_addr, &rt->rt6i_src.addr);
 473 }
 474
 475 /* Compare addresses exactly.
 476  * v4-mapped-v6 is also in consideration.
 477  */
 478 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
 479                             const union sctp_addr *addr2)
 480 {
 481         if (addr1->sa.sa_family != addr2->sa.sa_family) {
 482                 if (addr1->sa.sa_family == AF_INET &&
 483                     addr2->sa.sa_family == AF_INET6 &&
 484                     IPV6_ADDR_MAPPED == ipv6_addr_type(&addr2->v6.sin6_addr)) {
 485                         if (addr2->v6.sin6_port == addr1->v4.sin_port &&
 486                             addr2->v6.sin6_addr.s6_addr32[3] ==
 487                             addr1->v4.sin_addr.s_addr)
 488                                 return 1;
 489                 }
 490                 if (addr2->sa.sa_family == AF_INET &&
 491                     addr1->sa.sa_family == AF_INET6 &&
 492                     IPV6_ADDR_MAPPED == ipv6_addr_type(&addr1->v6.sin6_addr)) {
 493                         if (addr1->v6.sin6_port == addr2->v4.sin_port &&
 494                             addr1->v6.sin6_addr.s6_addr32[3] ==
 495                             addr2->v4.sin_addr.s_addr)
 496                                 return 1;
 497                 }
 498                 return 0;
 499         }
 500         if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
 501                 return 0;
 502         /* If this is a linklocal address, compare the scope_id. */
 503         if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) {
 504                 if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
 505                     (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) {
 506                         return 0;
 507                 }
 508         }
 509
 510         return 1;
 511 }
 512
 513 /* Initialize addr struct to INADDR_ANY. */
 514 static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port)
 515 {
 516         memset(addr, 0x00, sizeof(union sctp_addr));
 517         addr->v6.sin6_family = AF_INET6;
 518         addr->v6.sin6_port = port;
 519 }
 520
 521 /* Is this a wildcard address? */
 522 static int sctp_v6_is_any(const union sctp_addr *addr)
 523 {
 524         return ipv6_addr_any(&addr->v6.sin6_addr);
 525 }
 526
 527 /* Should this be available for binding?   */
 528 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
 529 {
 530         int type;
 531         struct in6_addr *in6 = (struct in6_addr *)&addr->v6.sin6_addr;
 532
 533         type = ipv6_addr_type(in6);
 534         if (IPV6_ADDR_ANY == type)
 535                 return 1;
 536         if (type == IPV6_ADDR_MAPPED) {
 537                 if (sp && !sp->v4mapped)
 538                         return 0;
 539                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
 540                         return 0;
 541                 sctp_v6_map_v4(addr);
 542                 return sctp_get_af_specific(AF_INET)->available(addr, sp);
 543         }
 544         if (!(type & IPV6_ADDR_UNICAST))
 545                 return 0;
 546
 547         return ipv6_chk_addr(in6, NULL, 0);
 548 }
 549
 550 /* This function checks if the address is a valid address to be used for
 551  * SCTP.
 552  *
 553  * Output:
 554  * Return 0 - If the address is a non-unicast or an illegal address.
 555  * Return 1 - If the address is a unicast.
 556  */
 557 static int sctp_v6_addr_valid(union sctp_addr *addr,
 558                               struct sctp_sock *sp,
 559                               const struct sk_buff *skb)
 560 {
 561         int ret = ipv6_addr_type(&addr->v6.sin6_addr);
 562
 563         /* Support v4-mapped-v6 address. */
 564         if (ret == IPV6_ADDR_MAPPED) {
 565                 /* Note: This routine is used in input, so v4-mapped-v6
 566                  * are disallowed here when there is no sctp_sock.
 567                  */
 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)->addr_valid(addr, sp, skb);
 574         }
 575
 576         /* Is this a non-unicast address */
 577         if (!(ret & IPV6_ADDR_UNICAST))
 578                 return 0;
 579
 580         return 1;
 581 }
 582
 583 /* What is the scope of 'addr'?  */
 584 static sctp_scope_t sctp_v6_scope(union sctp_addr *addr)
 585 {
 586         int v6scope;
 587         sctp_scope_t retval;
 588
 589         /* The IPv6 scope is really a set of bit fields.
 590          * See IFA_* in <net/if_inet6.h>.  Map to a generic SCTP scope.
 591          */
 592
 593         v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
 594         switch (v6scope) {
 595         case IFA_HOST:
 596                 retval = SCTP_SCOPE_LOOPBACK;
 597                 break;
 598         case IFA_LINK:
 599                 retval = SCTP_SCOPE_LINK;
 600                 break;
 601         case IFA_SITE:
 602                 retval = SCTP_SCOPE_PRIVATE;
 603                 break;
 604         default:
 605                 retval = SCTP_SCOPE_GLOBAL;
 606                 break;
 607         }
 608
 609         return retval;
 610 }
 611
 612 /* Create and initialize a new sk for the socket to be returned by accept(). */
 613 static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
 614                                              struct sctp_association *asoc)
 615 {
 616         struct inet_sock *inet = inet_sk(sk);
 617         struct sock *newsk;
 618         struct inet_sock *newinet;
 619         struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
 620         struct sctp6_sock *newsctp6sk;
 621
 622         newsk = sk_alloc(PF_INET6, GFP_KERNEL, sk->sk_prot, 1);
 623         if (!newsk)
 624                 goto out;
 625
 626         sock_init_data(NULL, newsk);
 627
 628         newsk->sk_type = SOCK_STREAM;
 629
 630         newsk->sk_prot = sk->sk_prot;
 631         newsk->sk_no_check = sk->sk_no_check;
 632         newsk->sk_reuse = sk->sk_reuse;
 633
 634         newsk->sk_destruct = inet_sock_destruct;
 635         newsk->sk_family = PF_INET6;
 636         newsk->sk_protocol = IPPROTO_SCTP;
 637         newsk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
 638         newsk->sk_shutdown = sk->sk_shutdown;
 639         sock_reset_flag(sk, SOCK_ZAPPED);
 640
 641         newsctp6sk = (struct sctp6_sock *)newsk;
 642         inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
 643
 644         newinet = inet_sk(newsk);
 645         newnp = inet6_sk(newsk);
 646
 647         memcpy(newnp, np, sizeof(struct ipv6_pinfo));
 648
 649         /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
 650          * and getpeername().
 651          */
 652         newinet->sport = inet->sport;
 653         newnp->saddr = np->saddr;
 654         newnp->rcv_saddr = np->rcv_saddr;
 655         newinet->dport = htons(asoc->peer.port);
 656         sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
 657
 658         /* Init the ipv4 part of the socket since we can have sockets
 659          * using v6 API for ipv4.
 660          */
 661         newinet->uc_ttl = -1;
 662         newinet->mc_loop = 1;
 663         newinet->mc_ttl = 1;
 664         newinet->mc_index = 0;
 665         newinet->mc_list = NULL;
 666
 667         if (ipv4_config.no_pmtu_disc)
 668                 newinet->pmtudisc = IP_PMTUDISC_DONT;
 669         else
 670                 newinet->pmtudisc = IP_PMTUDISC_WANT;
 671
 672         sk_refcnt_debug_inc(newsk);
 673
 674         if (newsk->sk_prot->init(newsk)) {
 675                 sk_common_release(newsk);
 676                 newsk = NULL;
 677         }
 678
 679 out:
 680         return newsk;
 681 }
 682
 683 /* Map v4 address to mapped v6 address */
 684 static void sctp_v6_addr_v4map(struct sctp_sock *sp, union sctp_addr *addr)
 685 {
 686         if (sp->v4mapped && AF_INET == addr->sa.sa_family)
 687                 sctp_v4_map_v6(addr);
 688 }
 689
 690 /* Where did this skb come from?  */
 691 static int sctp_v6_skb_iif(const struct sk_buff *skb)
 692 {
 693         struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb;
 694         return opt->iif;
 695 }
 696
 697 /* Was this packet marked by Explicit Congestion Notification? */
 698 static int sctp_v6_is_ce(const struct sk_buff *skb)
 699 {
 700         return *((__u32 *)(ipv6_hdr(skb))) & htonl(1 << 20);
 701 }
 702
 703 /* Dump the v6 addr to the seq file. */
 704 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
 705 {
 706         seq_printf(seq, NIP6_FMT " ", NIP6(addr->v6.sin6_addr));
 707 }
 708
 709 /* Initialize a PF_INET6 socket msg_name. */
 710 static void sctp_inet6_msgname(char *msgname, int *addr_len)
 711 {
 712         struct sockaddr_in6 *sin6;
 713
 714         sin6 = (struct sockaddr_in6 *)msgname;
 715         sin6->sin6_family = AF_INET6;
 716         sin6->sin6_flowinfo = 0;
 717         sin6->sin6_scope_id = 0; /*FIXME */
 718         *addr_len = sizeof(struct sockaddr_in6);
 719 }
 720
 721 /* Initialize a PF_INET msgname from a ulpevent. */
 722 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
 723                                      char *msgname, int *addrlen)
 724 {
 725         struct sockaddr_in6 *sin6, *sin6from;
 726
 727         if (msgname) {
 728                 union sctp_addr *addr;
 729                 struct sctp_association *asoc;
 730
 731                 asoc = event->asoc;
 732                 sctp_inet6_msgname(msgname, addrlen);
 733                 sin6 = (struct sockaddr_in6 *)msgname;
 734                 sin6->sin6_port = htons(asoc->peer.port);
 735                 addr = &asoc->peer.primary_addr;
 736
 737                 /* Note: If we go to a common v6 format, this code
 738                  * will change.
 739                  */
 740
 741                 /* Map ipv4 address into v4-mapped-on-v6 address.  */
 742                 if (sctp_sk(asoc->base.sk)->v4mapped &&
 743                     AF_INET == addr->sa.sa_family) {
 744                         sctp_v4_map_v6((union sctp_addr *)sin6);
 745                         sin6->sin6_addr.s6_addr32[3] =
 746                                 addr->v4.sin_addr.s_addr;
 747                         return;
 748                 }
 749
 750                 sin6from = &asoc->peer.primary_addr.v6;
 751                 ipv6_addr_copy(&sin6->sin6_addr, &sin6from->sin6_addr);
 752                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 753                         sin6->sin6_scope_id = sin6from->sin6_scope_id;
 754         }
 755 }
 756
 757 /* Initialize a msg_name from an inbound skb. */
 758 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
 759                                    int *addr_len)
 760 {
 761         struct sctphdr *sh;
 762         struct sockaddr_in6 *sin6;
 763
 764         if (msgname) {
 765                 sctp_inet6_msgname(msgname, addr_len);
 766                 sin6 = (struct sockaddr_in6 *)msgname;
 767                 sh = sctp_hdr(skb);
 768                 sin6->sin6_port = sh->source;
 769
 770                 /* Map ipv4 address into v4-mapped-on-v6 address. */
 771                 if (sctp_sk(skb->sk)->v4mapped &&
 772                     ip_hdr(skb)->version == 4) {
 773                         sctp_v4_map_v6((union sctp_addr *)sin6);
 774                         sin6->sin6_addr.s6_addr32[3] = ip_hdr(skb)->saddr;
 775                         return;
 776                 }
 777
 778                 /* Otherwise, just copy the v6 address. */
 779                 ipv6_addr_copy(&sin6->sin6_addr, &ipv6_hdr(skb)->saddr);
 780                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) {
 781                         struct sctp_ulpevent *ev = sctp_skb2event(skb);
 782                         sin6->sin6_scope_id = ev->iif;
 783                 }
 784         }
 785 }
 786
 787 /* Do we support this AF? */
 788 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
 789 {
 790         switch (family) {
 791         case AF_INET6:
 792                 return 1;
 793         /* v4-mapped-v6 addresses */
 794         case AF_INET:
 795                 if (!__ipv6_only_sock(sctp_opt2sk(sp)) && sp->v4mapped)
 796                         return 1;
 797         default:
 798                 return 0;
 799         }
 800 }
 801
 802 /* Address matching with wildcards allowed.  This extra level
 803  * of indirection lets us choose whether a PF_INET6 should
 804  * disallow any v4 addresses if we so choose.
 805  */
 806 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
 807                                const union sctp_addr *addr2,
 808                                struct sctp_sock *opt)
 809 {
 810         struct sctp_af *af1, *af2;
 811
 812         af1 = sctp_get_af_specific(addr1->sa.sa_family);
 813         af2 = sctp_get_af_specific(addr2->sa.sa_family);
 814
 815         if (!af1 || !af2)
 816                 return 0;
 817         /* Today, wildcard AF_INET/AF_INET6. */
 818         if (sctp_is_any(addr1) || sctp_is_any(addr2))
 819                 return 1;
 820
 821         if (addr1->sa.sa_family != addr2->sa.sa_family)
 822                 return 0;
 823
 824         return af1->cmp_addr(addr1, addr2);
 825 }
 826
 827 /* Verify that the provided sockaddr looks bindable.   Common verification,
 828  * has already been taken care of.
 829  */
 830 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
 831 {
 832         struct sctp_af *af;
 833
 834         /* ASSERT: address family has already been verified. */
 835         if (addr->sa.sa_family != AF_INET6)
 836                 af = sctp_get_af_specific(addr->sa.sa_family);
 837         else {
 838                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
 839                 struct net_device *dev;
 840
 841                 if (type & IPV6_ADDR_LINKLOCAL) {
 842                         if (!addr->v6.sin6_scope_id)
 843                                 return 0;
 844                         dev = dev_get_by_index(addr->v6.sin6_scope_id);
 845                         if (!dev)
 846                                 return 0;
 847                         dev_put(dev);
 848                 }
 849                 af = opt->pf->af;
 850         }
 851         return af->available(addr, opt);
 852 }
 853
 854 /* Verify that the provided sockaddr looks sendable.   Common verification,
 855  * has already been taken care of.
 856  */
 857 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
 858 {
 859         struct sctp_af *af = NULL;
 860
 861         /* ASSERT: address family has already been verified. */
 862         if (addr->sa.sa_family != AF_INET6)
 863                 af = sctp_get_af_specific(addr->sa.sa_family);
 864         else {
 865                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
 866                 struct net_device *dev;
 867
 868                 if (type & IPV6_ADDR_LINKLOCAL) {
 869                         if (!addr->v6.sin6_scope_id)
 870                                 return 0;
 871                         dev = dev_get_by_index(addr->v6.sin6_scope_id);
 872                         if (!dev)
 873                                 return 0;
 874                         dev_put(dev);
 875                 }
 876                 af = opt->pf->af;
 877         }
 878
 879         return af != NULL;
 880 }
 881
 882 /* Fill in Supported Address Type information for INIT and INIT-ACK
 883  * chunks.   Note: In the future, we may want to look at sock options
 884  * to determine whether a PF_INET6 socket really wants to have IPV4
 885  * addresses.
 886  * Returns number of addresses supported.
 887  */
 888 static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
 889                                       __be16 *types)
 890 {
 891         types[0] = SCTP_PARAM_IPV4_ADDRESS;
 892         types[1] = SCTP_PARAM_IPV6_ADDRESS;
 893         return 2;
 894 }
 895
 896 static const struct proto_ops inet6_seqpacket_ops = {
 897         .family            = PF_INET6,
 898         .owner             = THIS_MODULE,
 899         .release           = inet6_release,
 900         .bind              = inet6_bind,
 901         .connect           = inet_dgram_connect,
 902         .socketpair        = sock_no_socketpair,
 903         .accept            = inet_accept,
 904         .getname           = inet6_getname,
 905         .poll              = sctp_poll,
 906         .ioctl             = inet6_ioctl,
 907         .listen            = sctp_inet_listen,
 908         .shutdown          = inet_shutdown,
 909         .setsockopt        = sock_common_setsockopt,
 910         .getsockopt        = sock_common_getsockopt,
 911         .sendmsg           = inet_sendmsg,
 912         .recvmsg           = sock_common_recvmsg,
 913         .mmap              = sock_no_mmap,
 914 #ifdef CONFIG_COMPAT
 915         .compat_setsockopt = compat_sock_common_setsockopt,
 916         .compat_getsockopt = compat_sock_common_getsockopt,
 917 #endif
 918 };
 919
 920 static struct inet_protosw sctpv6_seqpacket_protosw = {
 921         .type          = SOCK_SEQPACKET,
 922         .protocol      = IPPROTO_SCTP,
 923         .prot          = &sctpv6_prot,
 924         .ops           = &inet6_seqpacket_ops,
 925         .capability    = -1,
 926         .no_check      = 0,
 927         .flags         = SCTP_PROTOSW_FLAG
 928 };
 929 static struct inet_protosw sctpv6_stream_protosw = {
 930         .type          = SOCK_STREAM,
 931         .protocol      = IPPROTO_SCTP,
 932         .prot          = &sctpv6_prot,
 933         .ops           = &inet6_seqpacket_ops,
 934         .capability    = -1,
 935         .no_check      = 0,
 936         .flags         = SCTP_PROTOSW_FLAG,
 937 };
 938
 939 static int sctp6_rcv(struct sk_buff **pskb)
 940 {
 941         return sctp_rcv(*pskb) ? -1 : 0;
 942 }
 943
 944 static struct inet6_protocol sctpv6_protocol = {
 945         .handler      = sctp6_rcv,
 946         .err_handler  = sctp_v6_err,
 947         .flags        = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
 948 };
 949
 950 static struct sctp_af sctp_ipv6_specific = {
 951         .sa_family         = AF_INET6,
 952         .sctp_xmit         = sctp_v6_xmit,
 953         .setsockopt        = ipv6_setsockopt,
 954         .getsockopt        = ipv6_getsockopt,
 955         .get_dst           = sctp_v6_get_dst,
 956         .get_saddr         = sctp_v6_get_saddr,
 957         .copy_addrlist     = sctp_v6_copy_addrlist,
 958         .from_skb          = sctp_v6_from_skb,
 959         .from_sk           = sctp_v6_from_sk,
 960         .to_sk_saddr       = sctp_v6_to_sk_saddr,
 961         .to_sk_daddr       = sctp_v6_to_sk_daddr,
 962         .from_addr_param   = sctp_v6_from_addr_param,
 963         .to_addr_param     = sctp_v6_to_addr_param,
 964         .dst_saddr         = sctp_v6_dst_saddr,
 965         .cmp_addr          = sctp_v6_cmp_addr,
 966         .scope             = sctp_v6_scope,
 967         .addr_valid        = sctp_v6_addr_valid,
 968         .inaddr_any        = sctp_v6_inaddr_any,
 969         .is_any            = sctp_v6_is_any,
 970         .available         = sctp_v6_available,
 971         .skb_iif           = sctp_v6_skb_iif,
 972         .is_ce             = sctp_v6_is_ce,
 973         .seq_dump_addr     = sctp_v6_seq_dump_addr,
 974         .net_header_len    = sizeof(struct ipv6hdr),
 975         .sockaddr_len      = sizeof(struct sockaddr_in6),
 976 #ifdef CONFIG_COMPAT
 977         .compat_setsockopt = compat_ipv6_setsockopt,
 978         .compat_getsockopt = compat_ipv6_getsockopt,
 979 #endif
 980 };
 981
 982 static struct sctp_pf sctp_pf_inet6_specific = {
 983         .event_msgname = sctp_inet6_event_msgname,
 984         .skb_msgname   = sctp_inet6_skb_msgname,
 985         .af_supported  = sctp_inet6_af_supported,
 986         .cmp_addr      = sctp_inet6_cmp_addr,
 987         .bind_verify   = sctp_inet6_bind_verify,
 988         .send_verify   = sctp_inet6_send_verify,
 989         .supported_addrs = sctp_inet6_supported_addrs,
 990         .create_accept_sk = sctp_v6_create_accept_sk,
 991         .addr_v4map    = sctp_v6_addr_v4map,
 992         .af            = &sctp_ipv6_specific,
 993 };
 994
 995 /* Initialize IPv6 support and register with inet6 stack.  */
 996 int sctp_v6_init(void)
 997 {
 998         int rc = proto_register(&sctpv6_prot, 1);
 999
1000         if (rc)
1001                 goto out;
1002         /* Register inet6 protocol. */
1003         rc = -EAGAIN;
1004         if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
1005                 goto out_unregister_sctp_proto;
1006
1007         /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
1008         inet6_register_protosw(&sctpv6_seqpacket_protosw);
1009         inet6_register_protosw(&sctpv6_stream_protosw);
1010
1011         /* Register the SCTP specific PF_INET6 functions. */
1012         sctp_register_pf(&sctp_pf_inet6_specific, PF_INET6);
1013
1014         /* Register the SCTP specific AF_INET6 functions. */
1015         sctp_register_af(&sctp_ipv6_specific);
1016
1017         /* Register notifier for inet6 address additions/deletions. */
1018         register_inet6addr_notifier(&sctp_inet6addr_notifier);
1019         rc = 0;
1020 out:
1021         return rc;
1022 out_unregister_sctp_proto:
1023         proto_unregister(&sctpv6_prot);
1024         goto out;
1025 }
1026
1027 /* IPv6 specific exit support. */
1028 void sctp_v6_exit(void)
1029 {
1030         list_del(&sctp_ipv6_specific.list);
1031         inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
1032         inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
1033         inet6_unregister_protosw(&sctpv6_stream_protosw);
1034         unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1035         proto_unregister(&sctpv6_prot);
1036 }