Pileus Git - ~andy/linux/blob - net/sctp/ipv6.c

   1 /* SCTP kernel implementation
   2  * (C) Copyright IBM Corp. 2002, 2004
   3  * Copyright (c) 2001 Nokia, Inc.
   4  * Copyright (c) 2001 La Monte H.P. Yarroll
   5  * Copyright (c) 2002-2003 Intel Corp.
   6  *
   7  * This file is part of the SCTP kernel implementation
   8  *
   9  * SCTP over IPv6.
  10  *
  11  * This SCTP implementation is free software;
  12  * you can redistribute it and/or modify it under the terms of
  13  * the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2, or (at your option)
  15  * any later version.
  16  *
  17  * This SCTP implementation is distributed in the hope that it
  18  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
  19  *                 ************************
  20  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  21  * See the GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with GNU CC; see the file COPYING.  If not, write to
  25  * the Free Software Foundation, 59 Temple Place - Suite 330,
  26  * Boston, MA 02111-1307, USA.
  27  *
  28  * Please send any bug reports or fixes you make to the
  29  * email address(es):
  30  *    lksctp developers <lksctp-developers@lists.sourceforge.net>
  31  *
  32  * Or submit a bug report through the following website:
  33  *    http://www.sf.net/projects/lksctp
  34  *
  35  * Written or modified by:
  36  *    Le Yanqun             <yanqun.le@nokia.com>
  37  *    Hui Huang             <hui.huang@nokia.com>
  38  *    La Monte H.P. Yarroll <piggy@acm.org>
  39  *    Sridhar Samudrala     <sri@us.ibm.com>
  40  *    Jon Grimm             <jgrimm@us.ibm.com>
  41  *    Ardelle Fan           <ardelle.fan@intel.com>
  42  *
  43  * Based on:
  44  *      linux/net/ipv6/tcp_ipv6.c
  45  *
  46  * Any bugs reported given to us we will try to fix... any fixes shared will
  47  * be incorporated into the next SCTP release.
  48  */
  49
  50 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  51
  52 #include <linux/module.h>
  53 #include <linux/errno.h>
  54 #include <linux/types.h>
  55 #include <linux/socket.h>
  56 #include <linux/sockios.h>
  57 #include <linux/net.h>
  58 #include <linux/in.h>
  59 #include <linux/in6.h>
  60 #include <linux/netdevice.h>
  61 #include <linux/init.h>
  62 #include <linux/ipsec.h>
  63 #include <linux/slab.h>
  64
  65 #include <linux/ipv6.h>
  66 #include <linux/icmpv6.h>
  67 #include <linux/random.h>
  68 #include <linux/seq_file.h>
  69
  70 #include <net/protocol.h>
  71 #include <net/ndisc.h>
  72 #include <net/ip.h>
  73 #include <net/ipv6.h>
  74 #include <net/transp_v6.h>
  75 #include <net/addrconf.h>
  76 #include <net/ip6_route.h>
  77 #include <net/inet_common.h>
  78 #include <net/inet_ecn.h>
  79 #include <net/sctp/sctp.h>
  80
  81 #include <asm/uaccess.h>
  82
  83 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
  84                                          union sctp_addr *s2);
  85
  86 /* Event handler for inet6 address addition/deletion events.
  87  * The sctp_local_addr_list needs to be protocted by a spin lock since
  88  * multiple notifiers (say IPv4 and IPv6) may be running at the same
  89  * time and thus corrupt the list.
  90  * The reader side is protected with RCU.
  91  */
  92 static int sctp_inet6addr_event(struct notifier_block *this, unsigned long ev,
  93                                 void *ptr)
  94 {
  95         struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
  96         struct sctp_sockaddr_entry *addr = NULL;
  97         struct sctp_sockaddr_entry *temp;
  98         int found = 0;
  99
 100         switch (ev) {
 101         case NETDEV_UP:
 102                 addr = kmalloc(sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC);
 103                 if (addr) {
 104                         addr->a.v6.sin6_family = AF_INET6;
 105                         addr->a.v6.sin6_port = 0;
 106                         ipv6_addr_copy(&addr->a.v6.sin6_addr, &ifa->addr);
 107                         addr->a.v6.sin6_scope_id = ifa->idev->dev->ifindex;
 108                         addr->valid = 1;
 109                         spin_lock_bh(&sctp_local_addr_lock);
 110                         list_add_tail_rcu(&addr->list, &sctp_local_addr_list);
 111                         spin_unlock_bh(&sctp_local_addr_lock);
 112                 }
 113                 break;
 114         case NETDEV_DOWN:
 115                 spin_lock_bh(&sctp_local_addr_lock);
 116                 list_for_each_entry_safe(addr, temp,
 117                                         &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                                 found = 1;
 122                                 addr->valid = 0;
 123                                 list_del_rcu(&addr->list);
 124                                 break;
 125                         }
 126                 }
 127                 spin_unlock_bh(&sctp_local_addr_lock);
 128                 if (found)
 129                         call_rcu(&addr->rcu, sctp_local_addr_free);
 130                 break;
 131         }
 132
 133         return NOTIFY_DONE;
 134 }
 135
 136 static struct notifier_block sctp_inet6addr_notifier = {
 137         .notifier_call = sctp_inet6addr_event,
 138 };
 139
 140 /* ICMP error handler. */
 141 SCTP_STATIC void sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 142                              u8 type, u8 code, int offset, __be32 info)
 143 {
 144         struct inet6_dev *idev;
 145         struct sock *sk;
 146         struct sctp_association *asoc;
 147         struct sctp_transport *transport;
 148         struct ipv6_pinfo *np;
 149         sk_buff_data_t saveip, savesctp;
 150         int err;
 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(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(dev_net(skb->dev), 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                 sctp_icmp_frag_needed(sk, asoc, transport, ntohl(info));
 175                 goto out_unlock;
 176         case ICMPV6_PARAMPROB:
 177                 if (ICMPV6_UNK_NEXTHDR == code) {
 178                         sctp_icmp_proto_unreachable(sk, asoc, transport);
 179                         goto out_unlock;
 180                 }
 181                 break;
 182         default:
 183                 break;
 184         }
 185
 186         np = inet6_sk(sk);
 187         icmpv6_err_convert(type, code, &err);
 188         if (!sock_owned_by_user(sk) && np->recverr) {
 189                 sk->sk_err = err;
 190                 sk->sk_error_report(sk);
 191         } else {  /* Only an error on timeout */
 192                 sk->sk_err_soft = err;
 193         }
 194
 195 out_unlock:
 196         sctp_err_finish(sk, asoc);
 197 out:
 198         if (likely(idev != NULL))
 199                 in6_dev_put(idev);
 200 }
 201
 202 /* Based on tcp_v6_xmit() in tcp_ipv6.c. */
 203 static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *transport)
 204 {
 205         struct sock *sk = skb->sk;
 206         struct ipv6_pinfo *np = inet6_sk(sk);
 207         struct flowi6 fl6;
 208
 209         memset(&fl6, 0, sizeof(fl6));
 210
 211         fl6.flowi6_proto = sk->sk_protocol;
 212
 213         /* Fill in the dest address from the route entry passed with the skb
 214          * and the source address from the transport.
 215          */
 216         ipv6_addr_copy(&fl6.daddr, &transport->ipaddr.v6.sin6_addr);
 217         ipv6_addr_copy(&fl6.saddr, &transport->saddr.v6.sin6_addr);
 218
 219         fl6.flowlabel = np->flow_label;
 220         IP6_ECN_flow_xmit(sk, fl6.flowlabel);
 221         if (ipv6_addr_type(&fl6.saddr) & IPV6_ADDR_LINKLOCAL)
 222                 fl6.flowi6_oif = transport->saddr.v6.sin6_scope_id;
 223         else
 224                 fl6.flowi6_oif = sk->sk_bound_dev_if;
 225
 226         if (np->opt && np->opt->srcrt) {
 227                 struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
 228                 ipv6_addr_copy(&fl6.daddr, rt0->addr);
 229         }
 230
 231         SCTP_DEBUG_PRINTK("%s: skb:%p, len:%d, src:%pI6 dst:%pI6\n",
 232                           __func__, skb, skb->len,
 233                           &fl6.saddr, &fl6.daddr);
 234
 235         SCTP_INC_STATS(SCTP_MIB_OUTSCTPPACKS);
 236
 237         if (!(transport->param_flags & SPP_PMTUD_ENABLE))
 238                 skb->local_df = 1;
 239
 240         return ip6_xmit(sk, skb, &fl6, np->opt);
 241 }
 242
 243 /* Returns the dst cache entry for the given source and destination ip
 244  * addresses.
 245  */
 246 static struct dst_entry *sctp_v6_get_dst(struct sctp_association *asoc,
 247                                          union sctp_addr *daddr,
 248                                          union sctp_addr *saddr)
 249 {
 250         struct dst_entry *dst = NULL;
 251         struct flowi6 fl6;
 252         struct sctp_bind_addr *bp;
 253         struct sctp_sockaddr_entry *laddr;
 254         union sctp_addr *baddr = NULL;
 255         __u8 matchlen = 0;
 256         __u8 bmatchlen;
 257         sctp_scope_t scope;
 258
 259         memset(&fl6, 0, sizeof(fl6));
 260         ipv6_addr_copy(&fl6.daddr, &daddr->v6.sin6_addr);
 261         if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
 262                 fl6.flowi6_oif = daddr->v6.sin6_scope_id;
 263
 264
 265         SCTP_DEBUG_PRINTK("%s: DST=%pI6 ", __func__, &fl6.daddr);
 266
 267         if (saddr) {
 268                 ipv6_addr_copy(&fl6.saddr, &saddr->v6.sin6_addr);
 269                 SCTP_DEBUG_PRINTK("SRC=%pI6 - ", &fl6.saddr);
 270         }
 271
 272         dst = ip6_route_output(&init_net, NULL, &fl6);
 273         if (!asoc || saddr)
 274                 goto out;
 275
 276         if (dst->error) {
 277                 dst_release(dst);
 278                 dst = NULL;
 279                 bp = &asoc->base.bind_addr;
 280                 scope = sctp_scope(daddr);
 281                 /* Walk through the bind address list and try to get a dst that
 282                  * matches a bind address as the source address.
 283                  */
 284                 rcu_read_lock();
 285                 list_for_each_entry_rcu(laddr, &bp->address_list, list) {
 286                         if (!laddr->valid)
 287                                 continue;
 288                         if ((laddr->state == SCTP_ADDR_SRC) &&
 289                             (laddr->a.sa.sa_family == AF_INET6) &&
 290                             (scope <= sctp_scope(&laddr->a))) {
 291                                 bmatchlen = sctp_v6_addr_match_len(daddr,
 292                                                                    &laddr->a);
 293                                 if (!baddr || (matchlen < bmatchlen)) {
 294                                         baddr = &laddr->a;
 295                                         matchlen = bmatchlen;
 296                                 }
 297                         }
 298                 }
 299                 rcu_read_unlock();
 300                 if (baddr) {
 301                         ipv6_addr_copy(&fl6.saddr, &baddr->v6.sin6_addr);
 302                         dst = ip6_route_output(&init_net, NULL, &fl6);
 303                 }
 304         }
 305 out:
 306         if (!dst->error) {
 307                 struct rt6_info *rt;
 308                 rt = (struct rt6_info *)dst;
 309                 SCTP_DEBUG_PRINTK("rt6_dst:%pI6 rt6_src:%pI6\n",
 310                         &rt->rt6i_dst.addr, &rt->rt6i_src.addr);
 311                 return dst;
 312         }
 313         SCTP_DEBUG_PRINTK("NO ROUTE\n");
 314         dst_release(dst);
 315         return NULL;
 316 }
 317
 318 /* Returns the number of consecutive initial bits that match in the 2 ipv6
 319  * addresses.
 320  */
 321 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
 322                                          union sctp_addr *s2)
 323 {
 324         return ipv6_addr_diff(&s1->v6.sin6_addr, &s2->v6.sin6_addr);
 325 }
 326
 327 /* Fills in the source address(saddr) based on the destination address(daddr)
 328  * and asoc's bind address list.
 329  */
 330 static void sctp_v6_get_saddr(struct sctp_sock *sk,
 331                               struct sctp_association *asoc,
 332                               struct dst_entry *dst,
 333                               union sctp_addr *daddr,
 334                               union sctp_addr *saddr)
 335 {
 336         struct sctp_bind_addr *bp;
 337         struct sctp_sockaddr_entry *laddr;
 338         sctp_scope_t scope;
 339         union sctp_addr *baddr = NULL;
 340         __u8 matchlen = 0;
 341         __u8 bmatchlen;
 342
 343         SCTP_DEBUG_PRINTK("%s: asoc:%p dst:%p daddr:%pI6 ",
 344                           __func__, asoc, dst, &daddr->v6.sin6_addr);
 345
 346         if (!asoc) {
 347                 ipv6_dev_get_saddr(sock_net(sctp_opt2sk(sk)),
 348                                    dst ? ip6_dst_idev(dst)->dev : NULL,
 349                                    &daddr->v6.sin6_addr,
 350                                    inet6_sk(&sk->inet.sk)->srcprefs,
 351                                    &saddr->v6.sin6_addr);
 352                 SCTP_DEBUG_PRINTK("saddr from ipv6_get_saddr: %pI6\n",
 353                                   &saddr->v6.sin6_addr);
 354                 return;
 355         }
 356
 357         scope = sctp_scope(daddr);
 358
 359         bp = &asoc->base.bind_addr;
 360
 361         /* Go through the bind address list and find the best source address
 362          * that matches the scope of the destination address.
 363          */
 364         rcu_read_lock();
 365         list_for_each_entry_rcu(laddr, &bp->address_list, list) {
 366                 if (!laddr->valid)
 367                         continue;
 368                 if ((laddr->state == SCTP_ADDR_SRC) &&
 369                     (laddr->a.sa.sa_family == AF_INET6) &&
 370                     (scope <= sctp_scope(&laddr->a))) {
 371                         bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
 372                         if (!baddr || (matchlen < bmatchlen)) {
 373                                 baddr = &laddr->a;
 374                                 matchlen = bmatchlen;
 375                         }
 376                 }
 377         }
 378
 379         if (baddr) {
 380                 memcpy(saddr, baddr, sizeof(union sctp_addr));
 381                 SCTP_DEBUG_PRINTK("saddr: %pI6\n", &saddr->v6.sin6_addr);
 382         } else {
 383                 pr_err("%s: asoc:%p Could not find a valid source "
 384                        "address for the dest:%pI6\n",
 385                        __func__, asoc, &daddr->v6.sin6_addr);
 386         }
 387
 388         rcu_read_unlock();
 389 }
 390
 391 /* Make a copy of all potential local addresses. */
 392 static void sctp_v6_copy_addrlist(struct list_head *addrlist,
 393                                   struct net_device *dev)
 394 {
 395         struct inet6_dev *in6_dev;
 396         struct inet6_ifaddr *ifp;
 397         struct sctp_sockaddr_entry *addr;
 398
 399         rcu_read_lock();
 400         if ((in6_dev = __in6_dev_get(dev)) == NULL) {
 401                 rcu_read_unlock();
 402                 return;
 403         }
 404
 405         read_lock_bh(&in6_dev->lock);
 406         list_for_each_entry(ifp, &in6_dev->addr_list, if_list) {
 407                 /* Add the address to the local list.  */
 408                 addr = t_new(struct sctp_sockaddr_entry, GFP_ATOMIC);
 409                 if (addr) {
 410                         addr->a.v6.sin6_family = AF_INET6;
 411                         addr->a.v6.sin6_port = 0;
 412                         ipv6_addr_copy(&addr->a.v6.sin6_addr, &ifp->addr);
 413                         addr->a.v6.sin6_scope_id = dev->ifindex;
 414                         addr->valid = 1;
 415                         INIT_LIST_HEAD(&addr->list);
 416                         list_add_tail(&addr->list, addrlist);
 417                 }
 418         }
 419
 420         read_unlock_bh(&in6_dev->lock);
 421         rcu_read_unlock();
 422 }
 423
 424 /* Initialize a sockaddr_storage from in incoming skb. */
 425 static void sctp_v6_from_skb(union sctp_addr *addr,struct sk_buff *skb,
 426                              int is_saddr)
 427 {
 428         void *from;
 429         __be16 *port;
 430         struct sctphdr *sh;
 431
 432         port = &addr->v6.sin6_port;
 433         addr->v6.sin6_family = AF_INET6;
 434         addr->v6.sin6_flowinfo = 0; /* FIXME */
 435         addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif;
 436
 437         sh = sctp_hdr(skb);
 438         if (is_saddr) {
 439                 *port  = sh->source;
 440                 from = &ipv6_hdr(skb)->saddr;
 441         } else {
 442                 *port = sh->dest;
 443                 from = &ipv6_hdr(skb)->daddr;
 444         }
 445         ipv6_addr_copy(&addr->v6.sin6_addr, from);
 446 }
 447
 448 /* Initialize an sctp_addr from a socket. */
 449 static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
 450 {
 451         addr->v6.sin6_family = AF_INET6;
 452         addr->v6.sin6_port = 0;
 453         ipv6_addr_copy(&addr->v6.sin6_addr, &inet6_sk(sk)->rcv_saddr);
 454 }
 455
 456 /* Initialize sk->sk_rcv_saddr from sctp_addr. */
 457 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
 458 {
 459         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
 460                 inet6_sk(sk)->rcv_saddr.s6_addr32[0] = 0;
 461                 inet6_sk(sk)->rcv_saddr.s6_addr32[1] = 0;
 462                 inet6_sk(sk)->rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
 463                 inet6_sk(sk)->rcv_saddr.s6_addr32[3] =
 464                         addr->v4.sin_addr.s_addr;
 465         } else {
 466                 ipv6_addr_copy(&inet6_sk(sk)->rcv_saddr, &addr->v6.sin6_addr);
 467         }
 468 }
 469
 470 /* Initialize sk->sk_daddr from sctp_addr. */
 471 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
 472 {
 473         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
 474                 inet6_sk(sk)->daddr.s6_addr32[0] = 0;
 475                 inet6_sk(sk)->daddr.s6_addr32[1] = 0;
 476                 inet6_sk(sk)->daddr.s6_addr32[2] = htonl(0x0000ffff);
 477                 inet6_sk(sk)->daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
 478         } else {
 479                 ipv6_addr_copy(&inet6_sk(sk)->daddr, &addr->v6.sin6_addr);
 480         }
 481 }
 482
 483 /* Initialize a sctp_addr from an address parameter. */
 484 static void sctp_v6_from_addr_param(union sctp_addr *addr,
 485                                     union sctp_addr_param *param,
 486                                     __be16 port, int iif)
 487 {
 488         addr->v6.sin6_family = AF_INET6;
 489         addr->v6.sin6_port = port;
 490         addr->v6.sin6_flowinfo = 0; /* BUG */
 491         ipv6_addr_copy(&addr->v6.sin6_addr, &param->v6.addr);
 492         addr->v6.sin6_scope_id = iif;
 493 }
 494
 495 /* Initialize an address parameter from a sctp_addr and return the length
 496  * of the address parameter.
 497  */
 498 static int sctp_v6_to_addr_param(const union sctp_addr *addr,
 499                                  union sctp_addr_param *param)
 500 {
 501         int length = sizeof(sctp_ipv6addr_param_t);
 502
 503         param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
 504         param->v6.param_hdr.length = htons(length);
 505         ipv6_addr_copy(&param->v6.addr, &addr->v6.sin6_addr);
 506
 507         return length;
 508 }
 509
 510 /* Initialize a sctp_addr from a dst_entry. */
 511 static void sctp_v6_dst_saddr(union sctp_addr *addr, struct dst_entry *dst,
 512                               __be16 port)
 513 {
 514         struct rt6_info *rt = (struct rt6_info *)dst;
 515         addr->sa.sa_family = AF_INET6;
 516         addr->v6.sin6_port = port;
 517         ipv6_addr_copy(&addr->v6.sin6_addr, &rt->rt6i_src.addr);
 518 }
 519
 520 /* Compare addresses exactly.
 521  * v4-mapped-v6 is also in consideration.
 522  */
 523 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
 524                             const union sctp_addr *addr2)
 525 {
 526         if (addr1->sa.sa_family != addr2->sa.sa_family) {
 527                 if (addr1->sa.sa_family == AF_INET &&
 528                     addr2->sa.sa_family == AF_INET6 &&
 529                     ipv6_addr_v4mapped(&addr2->v6.sin6_addr)) {
 530                         if (addr2->v6.sin6_port == addr1->v4.sin_port &&
 531                             addr2->v6.sin6_addr.s6_addr32[3] ==
 532                             addr1->v4.sin_addr.s_addr)
 533                                 return 1;
 534                 }
 535                 if (addr2->sa.sa_family == AF_INET &&
 536                     addr1->sa.sa_family == AF_INET6 &&
 537                     ipv6_addr_v4mapped(&addr1->v6.sin6_addr)) {
 538                         if (addr1->v6.sin6_port == addr2->v4.sin_port &&
 539                             addr1->v6.sin6_addr.s6_addr32[3] ==
 540                             addr2->v4.sin_addr.s_addr)
 541                                 return 1;
 542                 }
 543                 return 0;
 544         }
 545         if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
 546                 return 0;
 547         /* If this is a linklocal address, compare the scope_id. */
 548         if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) {
 549                 if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
 550                     (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) {
 551                         return 0;
 552                 }
 553         }
 554
 555         return 1;
 556 }
 557
 558 /* Initialize addr struct to INADDR_ANY. */
 559 static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port)
 560 {
 561         memset(addr, 0x00, sizeof(union sctp_addr));
 562         addr->v6.sin6_family = AF_INET6;
 563         addr->v6.sin6_port = port;
 564 }
 565
 566 /* Is this a wildcard address? */
 567 static int sctp_v6_is_any(const union sctp_addr *addr)
 568 {
 569         return ipv6_addr_any(&addr->v6.sin6_addr);
 570 }
 571
 572 /* Should this be available for binding?   */
 573 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
 574 {
 575         int type;
 576         const struct in6_addr *in6 = (const struct in6_addr *)&addr->v6.sin6_addr;
 577
 578         type = ipv6_addr_type(in6);
 579         if (IPV6_ADDR_ANY == type)
 580                 return 1;
 581         if (type == IPV6_ADDR_MAPPED) {
 582                 if (sp && !sp->v4mapped)
 583                         return 0;
 584                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
 585                         return 0;
 586                 sctp_v6_map_v4(addr);
 587                 return sctp_get_af_specific(AF_INET)->available(addr, sp);
 588         }
 589         if (!(type & IPV6_ADDR_UNICAST))
 590                 return 0;
 591
 592         return ipv6_chk_addr(&init_net, in6, NULL, 0);
 593 }
 594
 595 /* This function checks if the address is a valid address to be used for
 596  * SCTP.
 597  *
 598  * Output:
 599  * Return 0 - If the address is a non-unicast or an illegal address.
 600  * Return 1 - If the address is a unicast.
 601  */
 602 static int sctp_v6_addr_valid(union sctp_addr *addr,
 603                               struct sctp_sock *sp,
 604                               const struct sk_buff *skb)
 605 {
 606         int ret = ipv6_addr_type(&addr->v6.sin6_addr);
 607
 608         /* Support v4-mapped-v6 address. */
 609         if (ret == IPV6_ADDR_MAPPED) {
 610                 /* Note: This routine is used in input, so v4-mapped-v6
 611                  * are disallowed here when there is no sctp_sock.
 612                  */
 613                 if (!sp || !sp->v4mapped)
 614                         return 0;
 615                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
 616                         return 0;
 617                 sctp_v6_map_v4(addr);
 618                 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb);
 619         }
 620
 621         /* Is this a non-unicast address */
 622         if (!(ret & IPV6_ADDR_UNICAST))
 623                 return 0;
 624
 625         return 1;
 626 }
 627
 628 /* What is the scope of 'addr'?  */
 629 static sctp_scope_t sctp_v6_scope(union sctp_addr *addr)
 630 {
 631         int v6scope;
 632         sctp_scope_t retval;
 633
 634         /* The IPv6 scope is really a set of bit fields.
 635          * See IFA_* in <net/if_inet6.h>.  Map to a generic SCTP scope.
 636          */
 637
 638         v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
 639         switch (v6scope) {
 640         case IFA_HOST:
 641                 retval = SCTP_SCOPE_LOOPBACK;
 642                 break;
 643         case IFA_LINK:
 644                 retval = SCTP_SCOPE_LINK;
 645                 break;
 646         case IFA_SITE:
 647                 retval = SCTP_SCOPE_PRIVATE;
 648                 break;
 649         default:
 650                 retval = SCTP_SCOPE_GLOBAL;
 651                 break;
 652         }
 653
 654         return retval;
 655 }
 656
 657 /* Create and initialize a new sk for the socket to be returned by accept(). */
 658 static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
 659                                              struct sctp_association *asoc)
 660 {
 661         struct sock *newsk;
 662         struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
 663         struct sctp6_sock *newsctp6sk;
 664
 665         newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot);
 666         if (!newsk)
 667                 goto out;
 668
 669         sock_init_data(NULL, newsk);
 670
 671         sctp_copy_sock(newsk, sk, asoc);
 672         sock_reset_flag(sk, SOCK_ZAPPED);
 673
 674         newsctp6sk = (struct sctp6_sock *)newsk;
 675         inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
 676
 677         sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped;
 678
 679         newnp = inet6_sk(newsk);
 680
 681         memcpy(newnp, np, sizeof(struct ipv6_pinfo));
 682
 683         /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
 684          * and getpeername().
 685          */
 686         sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
 687
 688         sk_refcnt_debug_inc(newsk);
 689
 690         if (newsk->sk_prot->init(newsk)) {
 691                 sk_common_release(newsk);
 692                 newsk = NULL;
 693         }
 694
 695 out:
 696         return newsk;
 697 }
 698
 699 /* Map v4 address to mapped v6 address */
 700 static void sctp_v6_addr_v4map(struct sctp_sock *sp, union sctp_addr *addr)
 701 {
 702         if (sp->v4mapped && AF_INET == addr->sa.sa_family)
 703                 sctp_v4_map_v6(addr);
 704 }
 705
 706 /* Where did this skb come from?  */
 707 static int sctp_v6_skb_iif(const struct sk_buff *skb)
 708 {
 709         struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb;
 710         return opt->iif;
 711 }
 712
 713 /* Was this packet marked by Explicit Congestion Notification? */
 714 static int sctp_v6_is_ce(const struct sk_buff *skb)
 715 {
 716         return *((__u32 *)(ipv6_hdr(skb))) & htonl(1 << 20);
 717 }
 718
 719 /* Dump the v6 addr to the seq file. */
 720 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
 721 {
 722         seq_printf(seq, "%pI6 ", &addr->v6.sin6_addr);
 723 }
 724
 725 static void sctp_v6_ecn_capable(struct sock *sk)
 726 {
 727         inet6_sk(sk)->tclass |= INET_ECN_ECT_0;
 728 }
 729
 730 /* Initialize a PF_INET6 socket msg_name. */
 731 static void sctp_inet6_msgname(char *msgname, int *addr_len)
 732 {
 733         struct sockaddr_in6 *sin6;
 734
 735         sin6 = (struct sockaddr_in6 *)msgname;
 736         sin6->sin6_family = AF_INET6;
 737         sin6->sin6_flowinfo = 0;
 738         sin6->sin6_scope_id = 0; /*FIXME */
 739         *addr_len = sizeof(struct sockaddr_in6);
 740 }
 741
 742 /* Initialize a PF_INET msgname from a ulpevent. */
 743 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
 744                                      char *msgname, int *addrlen)
 745 {
 746         struct sockaddr_in6 *sin6, *sin6from;
 747
 748         if (msgname) {
 749                 union sctp_addr *addr;
 750                 struct sctp_association *asoc;
 751
 752                 asoc = event->asoc;
 753                 sctp_inet6_msgname(msgname, addrlen);
 754                 sin6 = (struct sockaddr_in6 *)msgname;
 755                 sin6->sin6_port = htons(asoc->peer.port);
 756                 addr = &asoc->peer.primary_addr;
 757
 758                 /* Note: If we go to a common v6 format, this code
 759                  * will change.
 760                  */
 761
 762                 /* Map ipv4 address into v4-mapped-on-v6 address.  */
 763                 if (sctp_sk(asoc->base.sk)->v4mapped &&
 764                     AF_INET == addr->sa.sa_family) {
 765                         sctp_v4_map_v6((union sctp_addr *)sin6);
 766                         sin6->sin6_addr.s6_addr32[3] =
 767                                 addr->v4.sin_addr.s_addr;
 768                         return;
 769                 }
 770
 771                 sin6from = &asoc->peer.primary_addr.v6;
 772                 ipv6_addr_copy(&sin6->sin6_addr, &sin6from->sin6_addr);
 773                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 774                         sin6->sin6_scope_id = sin6from->sin6_scope_id;
 775         }
 776 }
 777
 778 /* Initialize a msg_name from an inbound skb. */
 779 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
 780                                    int *addr_len)
 781 {
 782         struct sctphdr *sh;
 783         struct sockaddr_in6 *sin6;
 784
 785         if (msgname) {
 786                 sctp_inet6_msgname(msgname, addr_len);
 787                 sin6 = (struct sockaddr_in6 *)msgname;
 788                 sh = sctp_hdr(skb);
 789                 sin6->sin6_port = sh->source;
 790
 791                 /* Map ipv4 address into v4-mapped-on-v6 address. */
 792                 if (sctp_sk(skb->sk)->v4mapped &&
 793                     ip_hdr(skb)->version == 4) {
 794                         sctp_v4_map_v6((union sctp_addr *)sin6);
 795                         sin6->sin6_addr.s6_addr32[3] = ip_hdr(skb)->saddr;
 796                         return;
 797                 }
 798
 799                 /* Otherwise, just copy the v6 address. */
 800                 ipv6_addr_copy(&sin6->sin6_addr, &ipv6_hdr(skb)->saddr);
 801                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) {
 802                         struct sctp_ulpevent *ev = sctp_skb2event(skb);
 803                         sin6->sin6_scope_id = ev->iif;
 804                 }
 805         }
 806 }
 807
 808 /* Do we support this AF? */
 809 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
 810 {
 811         switch (family) {
 812         case AF_INET6:
 813                 return 1;
 814         /* v4-mapped-v6 addresses */
 815         case AF_INET:
 816                 if (!__ipv6_only_sock(sctp_opt2sk(sp)))
 817                         return 1;
 818         default:
 819                 return 0;
 820         }
 821 }
 822
 823 /* Address matching with wildcards allowed.  This extra level
 824  * of indirection lets us choose whether a PF_INET6 should
 825  * disallow any v4 addresses if we so choose.
 826  */
 827 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
 828                                const union sctp_addr *addr2,
 829                                struct sctp_sock *opt)
 830 {
 831         struct sctp_af *af1, *af2;
 832         struct sock *sk = sctp_opt2sk(opt);
 833
 834         af1 = sctp_get_af_specific(addr1->sa.sa_family);
 835         af2 = sctp_get_af_specific(addr2->sa.sa_family);
 836
 837         if (!af1 || !af2)
 838                 return 0;
 839
 840         /* If the socket is IPv6 only, v4 addrs will not match */
 841         if (__ipv6_only_sock(sk) && af1 != af2)
 842                 return 0;
 843
 844         /* Today, wildcard AF_INET/AF_INET6. */
 845         if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2))
 846                 return 1;
 847
 848         if (addr1->sa.sa_family != addr2->sa.sa_family)
 849                 return 0;
 850
 851         return af1->cmp_addr(addr1, addr2);
 852 }
 853
 854 /* Verify that the provided sockaddr looks bindable.   Common verification,
 855  * has already been taken care of.
 856  */
 857 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
 858 {
 859         struct sctp_af *af;
 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                         rcu_read_lock();
 872                         dev = dev_get_by_index_rcu(&init_net,
 873                                                    addr->v6.sin6_scope_id);
 874                         if (!dev ||
 875                             !ipv6_chk_addr(&init_net, &addr->v6.sin6_addr,
 876                                            dev, 0)) {
 877                                 rcu_read_unlock();
 878                                 return 0;
 879                         }
 880                         rcu_read_unlock();
 881                 } else if (type == IPV6_ADDR_MAPPED) {
 882                         if (!opt->v4mapped)
 883                                 return 0;
 884                 }
 885
 886                 af = opt->pf->af;
 887         }
 888         return af->available(addr, opt);
 889 }
 890
 891 /* Verify that the provided sockaddr looks sendable.   Common verification,
 892  * has already been taken care of.
 893  */
 894 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
 895 {
 896         struct sctp_af *af = NULL;
 897
 898         /* ASSERT: address family has already been verified. */
 899         if (addr->sa.sa_family != AF_INET6)
 900                 af = sctp_get_af_specific(addr->sa.sa_family);
 901         else {
 902                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
 903                 struct net_device *dev;
 904
 905                 if (type & IPV6_ADDR_LINKLOCAL) {
 906                         if (!addr->v6.sin6_scope_id)
 907                                 return 0;
 908                         rcu_read_lock();
 909                         dev = dev_get_by_index_rcu(&init_net,
 910                                                    addr->v6.sin6_scope_id);
 911                         rcu_read_unlock();
 912                         if (!dev)
 913                                 return 0;
 914                 }
 915                 af = opt->pf->af;
 916         }
 917
 918         return af != NULL;
 919 }
 920
 921 /* Fill in Supported Address Type information for INIT and INIT-ACK
 922  * chunks.   Note: In the future, we may want to look at sock options
 923  * to determine whether a PF_INET6 socket really wants to have IPV4
 924  * addresses.
 925  * Returns number of addresses supported.
 926  */
 927 static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
 928                                       __be16 *types)
 929 {
 930         types[0] = SCTP_PARAM_IPV6_ADDRESS;
 931         if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) {
 932                 types[1] = SCTP_PARAM_IPV4_ADDRESS;
 933                 return 2;
 934         }
 935         return 1;
 936 }
 937
 938 static const struct proto_ops inet6_seqpacket_ops = {
 939         .family            = PF_INET6,
 940         .owner             = THIS_MODULE,
 941         .release           = inet6_release,
 942         .bind              = inet6_bind,
 943         .connect           = inet_dgram_connect,
 944         .socketpair        = sock_no_socketpair,
 945         .accept            = inet_accept,
 946         .getname           = inet6_getname,
 947         .poll              = sctp_poll,
 948         .ioctl             = inet6_ioctl,
 949         .listen            = sctp_inet_listen,
 950         .shutdown          = inet_shutdown,
 951         .setsockopt        = sock_common_setsockopt,
 952         .getsockopt        = sock_common_getsockopt,
 953         .sendmsg           = inet_sendmsg,
 954         .recvmsg           = sock_common_recvmsg,
 955         .mmap              = sock_no_mmap,
 956 #ifdef CONFIG_COMPAT
 957         .compat_setsockopt = compat_sock_common_setsockopt,
 958         .compat_getsockopt = compat_sock_common_getsockopt,
 959 #endif
 960 };
 961
 962 static struct inet_protosw sctpv6_seqpacket_protosw = {
 963         .type          = SOCK_SEQPACKET,
 964         .protocol      = IPPROTO_SCTP,
 965         .prot          = &sctpv6_prot,
 966         .ops           = &inet6_seqpacket_ops,
 967         .no_check      = 0,
 968         .flags         = SCTP_PROTOSW_FLAG
 969 };
 970 static struct inet_protosw sctpv6_stream_protosw = {
 971         .type          = SOCK_STREAM,
 972         .protocol      = IPPROTO_SCTP,
 973         .prot          = &sctpv6_prot,
 974         .ops           = &inet6_seqpacket_ops,
 975         .no_check      = 0,
 976         .flags         = SCTP_PROTOSW_FLAG,
 977 };
 978
 979 static int sctp6_rcv(struct sk_buff *skb)
 980 {
 981         return sctp_rcv(skb) ? -1 : 0;
 982 }
 983
 984 static const struct inet6_protocol sctpv6_protocol = {
 985         .handler      = sctp6_rcv,
 986         .err_handler  = sctp_v6_err,
 987         .flags        = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
 988 };
 989
 990 static struct sctp_af sctp_af_inet6 = {
 991         .sa_family         = AF_INET6,
 992         .sctp_xmit         = sctp_v6_xmit,
 993         .setsockopt        = ipv6_setsockopt,
 994         .getsockopt        = ipv6_getsockopt,
 995         .get_dst           = sctp_v6_get_dst,
 996         .get_saddr         = sctp_v6_get_saddr,
 997         .copy_addrlist     = sctp_v6_copy_addrlist,
 998         .from_skb          = sctp_v6_from_skb,
 999         .from_sk           = sctp_v6_from_sk,
1000         .to_sk_saddr       = sctp_v6_to_sk_saddr,
1001         .to_sk_daddr       = sctp_v6_to_sk_daddr,
1002         .from_addr_param   = sctp_v6_from_addr_param,
1003         .to_addr_param     = sctp_v6_to_addr_param,
1004         .dst_saddr         = sctp_v6_dst_saddr,
1005         .cmp_addr          = sctp_v6_cmp_addr,
1006         .scope             = sctp_v6_scope,
1007         .addr_valid        = sctp_v6_addr_valid,
1008         .inaddr_any        = sctp_v6_inaddr_any,
1009         .is_any            = sctp_v6_is_any,
1010         .available         = sctp_v6_available,
1011         .skb_iif           = sctp_v6_skb_iif,
1012         .is_ce             = sctp_v6_is_ce,
1013         .seq_dump_addr     = sctp_v6_seq_dump_addr,
1014         .ecn_capable       = sctp_v6_ecn_capable,
1015         .net_header_len    = sizeof(struct ipv6hdr),
1016         .sockaddr_len      = sizeof(struct sockaddr_in6),
1017 #ifdef CONFIG_COMPAT
1018         .compat_setsockopt = compat_ipv6_setsockopt,
1019         .compat_getsockopt = compat_ipv6_getsockopt,
1020 #endif
1021 };
1022
1023 static struct sctp_pf sctp_pf_inet6 = {
1024         .event_msgname = sctp_inet6_event_msgname,
1025         .skb_msgname   = sctp_inet6_skb_msgname,
1026         .af_supported  = sctp_inet6_af_supported,
1027         .cmp_addr      = sctp_inet6_cmp_addr,
1028         .bind_verify   = sctp_inet6_bind_verify,
1029         .send_verify   = sctp_inet6_send_verify,
1030         .supported_addrs = sctp_inet6_supported_addrs,
1031         .create_accept_sk = sctp_v6_create_accept_sk,
1032         .addr_v4map    = sctp_v6_addr_v4map,
1033         .af            = &sctp_af_inet6,
1034 };
1035
1036 /* Initialize IPv6 support and register with socket layer.  */
1037 void sctp_v6_pf_init(void)
1038 {
1039         /* Register the SCTP specific PF_INET6 functions. */
1040         sctp_register_pf(&sctp_pf_inet6, PF_INET6);
1041
1042         /* Register the SCTP specific AF_INET6 functions. */
1043         sctp_register_af(&sctp_af_inet6);
1044 }
1045
1046 void sctp_v6_pf_exit(void)
1047 {
1048         list_del(&sctp_af_inet6.list);
1049 }
1050
1051 /* Initialize IPv6 support and register with socket layer.  */
1052 int sctp_v6_protosw_init(void)
1053 {
1054         int rc;
1055
1056         rc = proto_register(&sctpv6_prot, 1);
1057         if (rc)
1058                 return rc;
1059
1060         /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
1061         inet6_register_protosw(&sctpv6_seqpacket_protosw);
1062         inet6_register_protosw(&sctpv6_stream_protosw);
1063
1064         return 0;
1065 }
1066
1067 void sctp_v6_protosw_exit(void)
1068 {
1069         inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
1070         inet6_unregister_protosw(&sctpv6_stream_protosw);
1071         proto_unregister(&sctpv6_prot);
1072 }
1073
1074
1075 /* Register with inet6 layer. */
1076 int sctp_v6_add_protocol(void)
1077 {
1078         /* Register notifier for inet6 address additions/deletions. */
1079         register_inet6addr_notifier(&sctp_inet6addr_notifier);
1080
1081         if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
1082                 return -EAGAIN;
1083
1084         return 0;
1085 }
1086
1087 /* Unregister with inet6 layer. */
1088 void sctp_v6_del_protocol(void)
1089 {
1090         inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
1091         unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1092 }