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 #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  * The sctp_local_addr_list needs to be protocted by a spin lock since
  82  * multiple notifiers (say IPv4 and IPv6) may be running at the same
  83  * time and thus corrupt the list.
  84  * The reader side is protected with RCU.
  85  */
  86 static int sctp_inet6addr_event(struct notifier_block *this, unsigned long ev,
  87                                 void *ptr)
  88 {
  89         struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
  90         struct sctp_sockaddr_entry *addr = NULL;
  91         struct sctp_sockaddr_entry *temp;
  92         int found = 0;
  93
  94         switch (ev) {
  95         case NETDEV_UP:
  96                 addr = kmalloc(sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC);
  97                 if (addr) {
  98                         addr->a.v6.sin6_family = AF_INET6;
  99                         addr->a.v6.sin6_port = 0;
 100                         memcpy(&addr->a.v6.sin6_addr, &ifa->addr,
 101                                  sizeof(struct in6_addr));
 102                         addr->a.v6.sin6_scope_id = ifa->idev->dev->ifindex;
 103                         addr->valid = 1;
 104                         spin_lock_bh(&sctp_local_addr_lock);
 105                         list_add_tail_rcu(&addr->list, &sctp_local_addr_list);
 106                         spin_unlock_bh(&sctp_local_addr_lock);
 107                 }
 108                 break;
 109         case NETDEV_DOWN:
 110                 spin_lock_bh(&sctp_local_addr_lock);
 111                 list_for_each_entry_safe(addr, temp,
 112                                         &sctp_local_addr_list, list) {
 113                         if (addr->a.sa.sa_family == AF_INET6 &&
 114                                         ipv6_addr_equal(&addr->a.v6.sin6_addr,
 115                                                 &ifa->addr)) {
 116                                 found = 1;
 117                                 addr->valid = 0;
 118                                 list_del_rcu(&addr->list);
 119                                 break;
 120                         }
 121                 }
 122                 spin_unlock_bh(&sctp_local_addr_lock);
 123                 if (found)
 124                         call_rcu(&addr->rcu, sctp_local_addr_free);
 125                 break;
 126         }
 127
 128         return NOTIFY_DONE;
 129 }
 130
 131 static struct notifier_block sctp_inet6addr_notifier = {
 132         .notifier_call = sctp_inet6addr_event,
 133 };
 134
 135 /* ICMP error handler. */
 136 SCTP_STATIC void sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 137                              int type, int code, int offset, __be32 info)
 138 {
 139         struct inet6_dev *idev;
 140         struct sock *sk;
 141         struct sctp_association *asoc;
 142         struct sctp_transport *transport;
 143         struct ipv6_pinfo *np;
 144         sk_buff_data_t saveip, savesctp;
 145         int err;
 146
 147         idev = in6_dev_get(skb->dev);
 148
 149         /* Fix up skb to look at the embedded net header. */
 150         saveip   = skb->network_header;
 151         savesctp = skb->transport_header;
 152         skb_reset_network_header(skb);
 153         skb_set_transport_header(skb, offset);
 154         sk = sctp_err_lookup(AF_INET6, skb, sctp_hdr(skb), &asoc, &transport);
 155         /* Put back, the original pointers. */
 156         skb->network_header   = saveip;
 157         skb->transport_header = savesctp;
 158         if (!sk) {
 159                 ICMP6_INC_STATS_BH(idev, ICMP6_MIB_INERRORS);
 160                 goto out;
 161         }
 162
 163         /* Warning:  The sock lock is held.  Remember to call
 164          * sctp_err_finish!
 165          */
 166
 167         switch (type) {
 168         case ICMPV6_PKT_TOOBIG:
 169                 sctp_icmp_frag_needed(sk, asoc, transport, ntohl(info));
 170                 goto out_unlock;
 171         case ICMPV6_PARAMPROB:
 172                 if (ICMPV6_UNK_NEXTHDR == code) {
 173                         sctp_icmp_proto_unreachable(sk, asoc, transport);
 174                         goto out_unlock;
 175                 }
 176                 break;
 177         default:
 178                 break;
 179         }
 180
 181         np = inet6_sk(sk);
 182         icmpv6_err_convert(type, code, &err);
 183         if (!sock_owned_by_user(sk) && np->recverr) {
 184                 sk->sk_err = err;
 185                 sk->sk_error_report(sk);
 186         } else {  /* Only an error on timeout */
 187                 sk->sk_err_soft = err;
 188         }
 189
 190 out_unlock:
 191         sctp_err_finish(sk, asoc);
 192 out:
 193         if (likely(idev != NULL))
 194                 in6_dev_put(idev);
 195 }
 196
 197 /* Based on tcp_v6_xmit() in tcp_ipv6.c. */
 198 static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *transport)
 199 {
 200         struct sock *sk = skb->sk;
 201         struct ipv6_pinfo *np = inet6_sk(sk);
 202         struct flowi fl;
 203
 204         memset(&fl, 0, sizeof(fl));
 205
 206         fl.proto = sk->sk_protocol;
 207
 208         /* Fill in the dest address from the route entry passed with the skb
 209          * and the source address from the transport.
 210          */
 211         ipv6_addr_copy(&fl.fl6_dst, &transport->ipaddr.v6.sin6_addr);
 212         ipv6_addr_copy(&fl.fl6_src, &transport->saddr.v6.sin6_addr);
 213
 214         fl.fl6_flowlabel = np->flow_label;
 215         IP6_ECN_flow_xmit(sk, fl.fl6_flowlabel);
 216         if (ipv6_addr_type(&fl.fl6_src) & IPV6_ADDR_LINKLOCAL)
 217                 fl.oif = transport->saddr.v6.sin6_scope_id;
 218         else
 219                 fl.oif = sk->sk_bound_dev_if;
 220
 221         if (np->opt && np->opt->srcrt) {
 222                 struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
 223                 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
 224         }
 225
 226         SCTP_DEBUG_PRINTK("%s: skb:%p, len:%d, "
 227                           "src:" NIP6_FMT " dst:" NIP6_FMT "\n",
 228                           __func__, skb, skb->len,
 229                           NIP6(fl.fl6_src), NIP6(fl.fl6_dst));
 230
 231         SCTP_INC_STATS(SCTP_MIB_OUTSCTPPACKS);
 232
 233         if (!(transport->param_flags & SPP_PMTUD_ENABLE))
 234                 skb->local_df = 1;
 235
 236         return ip6_xmit(sk, skb, &fl, np->opt, 0);
 237 }
 238
 239 /* Returns the dst cache entry for the given source and destination ip
 240  * addresses.
 241  */
 242 static struct dst_entry *sctp_v6_get_dst(struct sctp_association *asoc,
 243                                          union sctp_addr *daddr,
 244                                          union sctp_addr *saddr)
 245 {
 246         struct dst_entry *dst;
 247         struct flowi fl;
 248
 249         memset(&fl, 0, sizeof(fl));
 250         ipv6_addr_copy(&fl.fl6_dst, &daddr->v6.sin6_addr);
 251         if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
 252                 fl.oif = daddr->v6.sin6_scope_id;
 253
 254
 255         SCTP_DEBUG_PRINTK("%s: DST=" NIP6_FMT " ",
 256                           __func__, NIP6(fl.fl6_dst));
 257
 258         if (saddr) {
 259                 ipv6_addr_copy(&fl.fl6_src, &saddr->v6.sin6_addr);
 260                 SCTP_DEBUG_PRINTK(
 261                         "SRC=" NIP6_FMT " - ",
 262                         NIP6(fl.fl6_src));
 263         }
 264
 265         dst = ip6_route_output(&init_net, NULL, &fl);
 266         if (!dst->error) {
 267                 struct rt6_info *rt;
 268                 rt = (struct rt6_info *)dst;
 269                 SCTP_DEBUG_PRINTK(
 270                         "rt6_dst:" NIP6_FMT " rt6_src:" NIP6_FMT "\n",
 271                         NIP6(rt->rt6i_dst.addr), NIP6(rt->rt6i_src.addr));
 272                 return dst;
 273         }
 274         SCTP_DEBUG_PRINTK("NO ROUTE\n");
 275         dst_release(dst);
 276         return NULL;
 277 }
 278
 279 /* Returns the number of consecutive initial bits that match in the 2 ipv6
 280  * addresses.
 281  */
 282 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
 283                                          union sctp_addr *s2)
 284 {
 285         struct in6_addr *a1 = &s1->v6.sin6_addr;
 286         struct in6_addr *a2 = &s2->v6.sin6_addr;
 287         int i, j;
 288
 289         for (i = 0; i < 4 ; i++) {
 290                 __be32 a1xora2;
 291
 292                 a1xora2 = a1->s6_addr32[i] ^ a2->s6_addr32[i];
 293
 294                 if ((j = fls(ntohl(a1xora2))))
 295                         return (i * 32 + 32 - j);
 296         }
 297
 298         return (i*32);
 299 }
 300
 301 /* Fills in the source address(saddr) based on the destination address(daddr)
 302  * and asoc's bind address list.
 303  */
 304 static void sctp_v6_get_saddr(struct sctp_sock *sk,
 305                               struct sctp_association *asoc,
 306                               struct dst_entry *dst,
 307                               union sctp_addr *daddr,
 308                               union sctp_addr *saddr)
 309 {
 310         struct sctp_bind_addr *bp;
 311         struct sctp_sockaddr_entry *laddr;
 312         sctp_scope_t scope;
 313         union sctp_addr *baddr = NULL;
 314         __u8 matchlen = 0;
 315         __u8 bmatchlen;
 316
 317         SCTP_DEBUG_PRINTK("%s: asoc:%p dst:%p "
 318                           "daddr:" NIP6_FMT " ",
 319                           __func__, asoc, dst, NIP6(daddr->v6.sin6_addr));
 320
 321         if (!asoc) {
 322                 ipv6_dev_get_saddr(sock_net(sctp_opt2sk(sk)),
 323                                    dst ? ip6_dst_idev(dst)->dev : NULL,
 324                                    &daddr->v6.sin6_addr,
 325                                    inet6_sk(&sk->inet.sk)->srcprefs,
 326                                    &saddr->v6.sin6_addr);
 327                 SCTP_DEBUG_PRINTK("saddr from ipv6_get_saddr: " NIP6_FMT "\n",
 328                                   NIP6(saddr->v6.sin6_addr));
 329                 return;
 330         }
 331
 332         scope = sctp_scope(daddr);
 333
 334         bp = &asoc->base.bind_addr;
 335
 336         /* Go through the bind address list and find the best source address
 337          * that matches the scope of the destination address.
 338          */
 339         rcu_read_lock();
 340         list_for_each_entry_rcu(laddr, &bp->address_list, list) {
 341                 if (!laddr->valid)
 342                         continue;
 343                 if ((laddr->state == SCTP_ADDR_SRC) &&
 344                     (laddr->a.sa.sa_family == AF_INET6) &&
 345                     (scope <= sctp_scope(&laddr->a))) {
 346                         bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
 347                         if (!baddr || (matchlen < bmatchlen)) {
 348                                 baddr = &laddr->a;
 349                                 matchlen = bmatchlen;
 350                         }
 351                 }
 352         }
 353
 354         if (baddr) {
 355                 memcpy(saddr, baddr, sizeof(union sctp_addr));
 356                 SCTP_DEBUG_PRINTK("saddr: " NIP6_FMT "\n",
 357                                   NIP6(saddr->v6.sin6_addr));
 358         } else {
 359                 printk(KERN_ERR "%s: asoc:%p Could not find a valid source "
 360                        "address for the dest:" NIP6_FMT "\n",
 361                        __func__, asoc, NIP6(daddr->v6.sin6_addr));
 362         }
 363
 364         rcu_read_unlock();
 365 }
 366
 367 /* Make a copy of all potential local addresses. */
 368 static void sctp_v6_copy_addrlist(struct list_head *addrlist,
 369                                   struct net_device *dev)
 370 {
 371         struct inet6_dev *in6_dev;
 372         struct inet6_ifaddr *ifp;
 373         struct sctp_sockaddr_entry *addr;
 374
 375         rcu_read_lock();
 376         if ((in6_dev = __in6_dev_get(dev)) == NULL) {
 377                 rcu_read_unlock();
 378                 return;
 379         }
 380
 381         read_lock_bh(&in6_dev->lock);
 382         for (ifp = in6_dev->addr_list; ifp; ifp = ifp->if_next) {
 383                 /* Add the address to the local list.  */
 384                 addr = t_new(struct sctp_sockaddr_entry, GFP_ATOMIC);
 385                 if (addr) {
 386                         addr->a.v6.sin6_family = AF_INET6;
 387                         addr->a.v6.sin6_port = 0;
 388                         addr->a.v6.sin6_addr = ifp->addr;
 389                         addr->a.v6.sin6_scope_id = dev->ifindex;
 390                         addr->valid = 1;
 391                         INIT_LIST_HEAD(&addr->list);
 392                         INIT_RCU_HEAD(&addr->rcu);
 393                         list_add_tail(&addr->list, addrlist);
 394                 }
 395         }
 396
 397         read_unlock_bh(&in6_dev->lock);
 398         rcu_read_unlock();
 399 }
 400
 401 /* Initialize a sockaddr_storage from in incoming skb. */
 402 static void sctp_v6_from_skb(union sctp_addr *addr,struct sk_buff *skb,
 403                              int is_saddr)
 404 {
 405         void *from;
 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                 from = &ipv6_hdr(skb)->saddr;
 418         } else {
 419                 *port = sh->dest;
 420                 from = &ipv6_hdr(skb)->daddr;
 421         }
 422         ipv6_addr_copy(&addr->v6.sin6_addr, from);
 423 }
 424
 425 /* Initialize an sctp_addr from a socket. */
 426 static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
 427 {
 428         addr->v6.sin6_family = AF_INET6;
 429         addr->v6.sin6_port = 0;
 430         addr->v6.sin6_addr = inet6_sk(sk)->rcv_saddr;
 431 }
 432
 433 /* Initialize sk->sk_rcv_saddr from sctp_addr. */
 434 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
 435 {
 436         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
 437                 inet6_sk(sk)->rcv_saddr.s6_addr32[0] = 0;
 438                 inet6_sk(sk)->rcv_saddr.s6_addr32[1] = 0;
 439                 inet6_sk(sk)->rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
 440                 inet6_sk(sk)->rcv_saddr.s6_addr32[3] =
 441                         addr->v4.sin_addr.s_addr;
 442         } else {
 443                 inet6_sk(sk)->rcv_saddr = addr->v6.sin6_addr;
 444         }
 445 }
 446
 447 /* Initialize sk->sk_daddr from sctp_addr. */
 448 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
 449 {
 450         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
 451                 inet6_sk(sk)->daddr.s6_addr32[0] = 0;
 452                 inet6_sk(sk)->daddr.s6_addr32[1] = 0;
 453                 inet6_sk(sk)->daddr.s6_addr32[2] = htonl(0x0000ffff);
 454                 inet6_sk(sk)->daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
 455         } else {
 456                 inet6_sk(sk)->daddr = addr->v6.sin6_addr;
 457         }
 458 }
 459
 460 /* Initialize a sctp_addr from an address parameter. */
 461 static void sctp_v6_from_addr_param(union sctp_addr *addr,
 462                                     union sctp_addr_param *param,
 463                                     __be16 port, int iif)
 464 {
 465         addr->v6.sin6_family = AF_INET6;
 466         addr->v6.sin6_port = port;
 467         addr->v6.sin6_flowinfo = 0; /* BUG */
 468         ipv6_addr_copy(&addr->v6.sin6_addr, &param->v6.addr);
 469         addr->v6.sin6_scope_id = iif;
 470 }
 471
 472 /* Initialize an address parameter from a sctp_addr and return the length
 473  * of the address parameter.
 474  */
 475 static int sctp_v6_to_addr_param(const union sctp_addr *addr,
 476                                  union sctp_addr_param *param)
 477 {
 478         int length = sizeof(sctp_ipv6addr_param_t);
 479
 480         param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
 481         param->v6.param_hdr.length = htons(length);
 482         ipv6_addr_copy(&param->v6.addr, &addr->v6.sin6_addr);
 483
 484         return length;
 485 }
 486
 487 /* Initialize a sctp_addr from a dst_entry. */
 488 static void sctp_v6_dst_saddr(union sctp_addr *addr, struct dst_entry *dst,
 489                               __be16 port)
 490 {
 491         struct rt6_info *rt = (struct rt6_info *)dst;
 492         addr->sa.sa_family = AF_INET6;
 493         addr->v6.sin6_port = port;
 494         ipv6_addr_copy(&addr->v6.sin6_addr, &rt->rt6i_src.addr);
 495 }
 496
 497 /* Compare addresses exactly.
 498  * v4-mapped-v6 is also in consideration.
 499  */
 500 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
 501                             const union sctp_addr *addr2)
 502 {
 503         if (addr1->sa.sa_family != addr2->sa.sa_family) {
 504                 if (addr1->sa.sa_family == AF_INET &&
 505                     addr2->sa.sa_family == AF_INET6 &&
 506                     ipv6_addr_v4mapped(&addr2->v6.sin6_addr)) {
 507                         if (addr2->v6.sin6_port == addr1->v4.sin_port &&
 508                             addr2->v6.sin6_addr.s6_addr32[3] ==
 509                             addr1->v4.sin_addr.s_addr)
 510                                 return 1;
 511                 }
 512                 if (addr2->sa.sa_family == AF_INET &&
 513                     addr1->sa.sa_family == AF_INET6 &&
 514                     ipv6_addr_v4mapped(&addr1->v6.sin6_addr)) {
 515                         if (addr1->v6.sin6_port == addr2->v4.sin_port &&
 516                             addr1->v6.sin6_addr.s6_addr32[3] ==
 517                             addr2->v4.sin_addr.s_addr)
 518                                 return 1;
 519                 }
 520                 return 0;
 521         }
 522         if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
 523                 return 0;
 524         /* If this is a linklocal address, compare the scope_id. */
 525         if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) {
 526                 if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
 527                     (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) {
 528                         return 0;
 529                 }
 530         }
 531
 532         return 1;
 533 }
 534
 535 /* Initialize addr struct to INADDR_ANY. */
 536 static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port)
 537 {
 538         memset(addr, 0x00, sizeof(union sctp_addr));
 539         addr->v6.sin6_family = AF_INET6;
 540         addr->v6.sin6_port = port;
 541 }
 542
 543 /* Is this a wildcard address? */
 544 static int sctp_v6_is_any(const union sctp_addr *addr)
 545 {
 546         return ipv6_addr_any(&addr->v6.sin6_addr);
 547 }
 548
 549 /* Should this be available for binding?   */
 550 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
 551 {
 552         int type;
 553         struct in6_addr *in6 = (struct in6_addr *)&addr->v6.sin6_addr;
 554
 555         type = ipv6_addr_type(in6);
 556         if (IPV6_ADDR_ANY == type)
 557                 return 1;
 558         if (type == IPV6_ADDR_MAPPED) {
 559                 if (sp && !sp->v4mapped)
 560                         return 0;
 561                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
 562                         return 0;
 563                 sctp_v6_map_v4(addr);
 564                 return sctp_get_af_specific(AF_INET)->available(addr, sp);
 565         }
 566         if (!(type & IPV6_ADDR_UNICAST))
 567                 return 0;
 568
 569         return ipv6_chk_addr(&init_net, in6, NULL, 0);
 570 }
 571
 572 /* This function checks if the address is a valid address to be used for
 573  * SCTP.
 574  *
 575  * Output:
 576  * Return 0 - If the address is a non-unicast or an illegal address.
 577  * Return 1 - If the address is a unicast.
 578  */
 579 static int sctp_v6_addr_valid(union sctp_addr *addr,
 580                               struct sctp_sock *sp,
 581                               const struct sk_buff *skb)
 582 {
 583         int ret = ipv6_addr_type(&addr->v6.sin6_addr);
 584
 585         /* Support v4-mapped-v6 address. */
 586         if (ret == IPV6_ADDR_MAPPED) {
 587                 /* Note: This routine is used in input, so v4-mapped-v6
 588                  * are disallowed here when there is no sctp_sock.
 589                  */
 590                 if (!sp || !sp->v4mapped)
 591                         return 0;
 592                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
 593                         return 0;
 594                 sctp_v6_map_v4(addr);
 595                 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb);
 596         }
 597
 598         /* Is this a non-unicast address */
 599         if (!(ret & IPV6_ADDR_UNICAST))
 600                 return 0;
 601
 602         return 1;
 603 }
 604
 605 /* What is the scope of 'addr'?  */
 606 static sctp_scope_t sctp_v6_scope(union sctp_addr *addr)
 607 {
 608         int v6scope;
 609         sctp_scope_t retval;
 610
 611         /* The IPv6 scope is really a set of bit fields.
 612          * See IFA_* in <net/if_inet6.h>.  Map to a generic SCTP scope.
 613          */
 614
 615         v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
 616         switch (v6scope) {
 617         case IFA_HOST:
 618                 retval = SCTP_SCOPE_LOOPBACK;
 619                 break;
 620         case IFA_LINK:
 621                 retval = SCTP_SCOPE_LINK;
 622                 break;
 623         case IFA_SITE:
 624                 retval = SCTP_SCOPE_PRIVATE;
 625                 break;
 626         default:
 627                 retval = SCTP_SCOPE_GLOBAL;
 628                 break;
 629         }
 630
 631         return retval;
 632 }
 633
 634 /* Create and initialize a new sk for the socket to be returned by accept(). */
 635 static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
 636                                              struct sctp_association *asoc)
 637 {
 638         struct inet_sock *inet = inet_sk(sk);
 639         struct sock *newsk;
 640         struct inet_sock *newinet;
 641         struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
 642         struct sctp6_sock *newsctp6sk;
 643
 644         newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot);
 645         if (!newsk)
 646                 goto out;
 647
 648         sock_init_data(NULL, newsk);
 649
 650         newsk->sk_type = SOCK_STREAM;
 651
 652         newsk->sk_prot = sk->sk_prot;
 653         newsk->sk_no_check = sk->sk_no_check;
 654         newsk->sk_reuse = sk->sk_reuse;
 655
 656         newsk->sk_destruct = inet_sock_destruct;
 657         newsk->sk_family = PF_INET6;
 658         newsk->sk_protocol = IPPROTO_SCTP;
 659         newsk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
 660         newsk->sk_shutdown = sk->sk_shutdown;
 661         sock_reset_flag(sk, SOCK_ZAPPED);
 662
 663         newsctp6sk = (struct sctp6_sock *)newsk;
 664         inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
 665
 666         sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped;
 667
 668         newinet = inet_sk(newsk);
 669         newnp = inet6_sk(newsk);
 670
 671         memcpy(newnp, np, sizeof(struct ipv6_pinfo));
 672
 673         /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
 674          * and getpeername().
 675          */
 676         newinet->sport = inet->sport;
 677         newnp->saddr = np->saddr;
 678         newnp->rcv_saddr = np->rcv_saddr;
 679         newinet->dport = htons(asoc->peer.port);
 680         sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
 681
 682         /* Init the ipv4 part of the socket since we can have sockets
 683          * using v6 API for ipv4.
 684          */
 685         newinet->uc_ttl = -1;
 686         newinet->mc_loop = 1;
 687         newinet->mc_ttl = 1;
 688         newinet->mc_index = 0;
 689         newinet->mc_list = NULL;
 690
 691         if (ipv4_config.no_pmtu_disc)
 692                 newinet->pmtudisc = IP_PMTUDISC_DONT;
 693         else
 694                 newinet->pmtudisc = IP_PMTUDISC_WANT;
 695
 696         sk_refcnt_debug_inc(newsk);
 697
 698         if (newsk->sk_prot->init(newsk)) {
 699                 sk_common_release(newsk);
 700                 newsk = NULL;
 701         }
 702
 703 out:
 704         return newsk;
 705 }
 706
 707 /* Map v4 address to mapped v6 address */
 708 static void sctp_v6_addr_v4map(struct sctp_sock *sp, union sctp_addr *addr)
 709 {
 710         if (sp->v4mapped && AF_INET == addr->sa.sa_family)
 711                 sctp_v4_map_v6(addr);
 712 }
 713
 714 /* Where did this skb come from?  */
 715 static int sctp_v6_skb_iif(const struct sk_buff *skb)
 716 {
 717         struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb;
 718         return opt->iif;
 719 }
 720
 721 /* Was this packet marked by Explicit Congestion Notification? */
 722 static int sctp_v6_is_ce(const struct sk_buff *skb)
 723 {
 724         return *((__u32 *)(ipv6_hdr(skb))) & htonl(1 << 20);
 725 }
 726
 727 /* Dump the v6 addr to the seq file. */
 728 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
 729 {
 730         seq_printf(seq, NIP6_FMT " ", NIP6(addr->v6.sin6_addr));
 731 }
 732
 733 static void sctp_v6_ecn_capable(struct sock *sk)
 734 {
 735         inet6_sk(sk)->tclass |= INET_ECN_ECT_0;
 736 }
 737
 738 /* Initialize a PF_INET6 socket msg_name. */
 739 static void sctp_inet6_msgname(char *msgname, int *addr_len)
 740 {
 741         struct sockaddr_in6 *sin6;
 742
 743         sin6 = (struct sockaddr_in6 *)msgname;
 744         sin6->sin6_family = AF_INET6;
 745         sin6->sin6_flowinfo = 0;
 746         sin6->sin6_scope_id = 0; /*FIXME */
 747         *addr_len = sizeof(struct sockaddr_in6);
 748 }
 749
 750 /* Initialize a PF_INET msgname from a ulpevent. */
 751 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
 752                                      char *msgname, int *addrlen)
 753 {
 754         struct sockaddr_in6 *sin6, *sin6from;
 755
 756         if (msgname) {
 757                 union sctp_addr *addr;
 758                 struct sctp_association *asoc;
 759
 760                 asoc = event->asoc;
 761                 sctp_inet6_msgname(msgname, addrlen);
 762                 sin6 = (struct sockaddr_in6 *)msgname;
 763                 sin6->sin6_port = htons(asoc->peer.port);
 764                 addr = &asoc->peer.primary_addr;
 765
 766                 /* Note: If we go to a common v6 format, this code
 767                  * will change.
 768                  */
 769
 770                 /* Map ipv4 address into v4-mapped-on-v6 address.  */
 771                 if (sctp_sk(asoc->base.sk)->v4mapped &&
 772                     AF_INET == addr->sa.sa_family) {
 773                         sctp_v4_map_v6((union sctp_addr *)sin6);
 774                         sin6->sin6_addr.s6_addr32[3] =
 775                                 addr->v4.sin_addr.s_addr;
 776                         return;
 777                 }
 778
 779                 sin6from = &asoc->peer.primary_addr.v6;
 780                 ipv6_addr_copy(&sin6->sin6_addr, &sin6from->sin6_addr);
 781                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 782                         sin6->sin6_scope_id = sin6from->sin6_scope_id;
 783         }
 784 }
 785
 786 /* Initialize a msg_name from an inbound skb. */
 787 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
 788                                    int *addr_len)
 789 {
 790         struct sctphdr *sh;
 791         struct sockaddr_in6 *sin6;
 792
 793         if (msgname) {
 794                 sctp_inet6_msgname(msgname, addr_len);
 795                 sin6 = (struct sockaddr_in6 *)msgname;
 796                 sh = sctp_hdr(skb);
 797                 sin6->sin6_port = sh->source;
 798
 799                 /* Map ipv4 address into v4-mapped-on-v6 address. */
 800                 if (sctp_sk(skb->sk)->v4mapped &&
 801                     ip_hdr(skb)->version == 4) {
 802                         sctp_v4_map_v6((union sctp_addr *)sin6);
 803                         sin6->sin6_addr.s6_addr32[3] = ip_hdr(skb)->saddr;
 804                         return;
 805                 }
 806
 807                 /* Otherwise, just copy the v6 address. */
 808                 ipv6_addr_copy(&sin6->sin6_addr, &ipv6_hdr(skb)->saddr);
 809                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) {
 810                         struct sctp_ulpevent *ev = sctp_skb2event(skb);
 811                         sin6->sin6_scope_id = ev->iif;
 812                 }
 813         }
 814 }
 815
 816 /* Do we support this AF? */
 817 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
 818 {
 819         switch (family) {
 820         case AF_INET6:
 821                 return 1;
 822         /* v4-mapped-v6 addresses */
 823         case AF_INET:
 824                 if (!__ipv6_only_sock(sctp_opt2sk(sp)))
 825                         return 1;
 826         default:
 827                 return 0;
 828         }
 829 }
 830
 831 /* Address matching with wildcards allowed.  This extra level
 832  * of indirection lets us choose whether a PF_INET6 should
 833  * disallow any v4 addresses if we so choose.
 834  */
 835 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
 836                                const union sctp_addr *addr2,
 837                                struct sctp_sock *opt)
 838 {
 839         struct sctp_af *af1, *af2;
 840
 841         af1 = sctp_get_af_specific(addr1->sa.sa_family);
 842         af2 = sctp_get_af_specific(addr2->sa.sa_family);
 843
 844         if (!af1 || !af2)
 845                 return 0;
 846
 847         /* If the socket is IPv6 only, v4 addrs will not match */
 848         if (__ipv6_only_sock(sctp_opt2sk(opt)) && af1 != af2)
 849                 return 0;
 850
 851         /* Today, wildcard AF_INET/AF_INET6. */
 852         if (sctp_is_any(addr1) || sctp_is_any(addr2))
 853                 return 1;
 854
 855         if (addr1->sa.sa_family != addr2->sa.sa_family)
 856                 return 0;
 857
 858         return af1->cmp_addr(addr1, addr2);
 859 }
 860
 861 /* Verify that the provided sockaddr looks bindable.   Common verification,
 862  * has already been taken care of.
 863  */
 864 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
 865 {
 866         struct sctp_af *af;
 867
 868         /* ASSERT: address family has already been verified. */
 869         if (addr->sa.sa_family != AF_INET6)
 870                 af = sctp_get_af_specific(addr->sa.sa_family);
 871         else {
 872                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
 873                 struct net_device *dev;
 874
 875                 if (type & IPV6_ADDR_LINKLOCAL) {
 876                         if (!addr->v6.sin6_scope_id)
 877                                 return 0;
 878                         dev = dev_get_by_index(&init_net, addr->v6.sin6_scope_id);
 879                         if (!dev)
 880                                 return 0;
 881                         if (!ipv6_chk_addr(&init_net, &addr->v6.sin6_addr,
 882                                            dev, 0)) {
 883                                 dev_put(dev);
 884                                 return 0;
 885                         }
 886                         dev_put(dev);
 887                 } else if (type == IPV6_ADDR_MAPPED) {
 888                         if (!opt->v4mapped)
 889                                 return 0;
 890                 }
 891
 892                 af = opt->pf->af;
 893         }
 894         return af->available(addr, opt);
 895 }
 896
 897 /* Verify that the provided sockaddr looks sendable.   Common verification,
 898  * has already been taken care of.
 899  */
 900 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
 901 {
 902         struct sctp_af *af = NULL;
 903
 904         /* ASSERT: address family has already been verified. */
 905         if (addr->sa.sa_family != AF_INET6)
 906                 af = sctp_get_af_specific(addr->sa.sa_family);
 907         else {
 908                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
 909                 struct net_device *dev;
 910
 911                 if (type & IPV6_ADDR_LINKLOCAL) {
 912                         if (!addr->v6.sin6_scope_id)
 913                                 return 0;
 914                         dev = dev_get_by_index(&init_net, addr->v6.sin6_scope_id);
 915                         if (!dev)
 916                                 return 0;
 917                         dev_put(dev);
 918                 }
 919                 af = opt->pf->af;
 920         }
 921
 922         return af != NULL;
 923 }
 924
 925 /* Fill in Supported Address Type information for INIT and INIT-ACK
 926  * chunks.   Note: In the future, we may want to look at sock options
 927  * to determine whether a PF_INET6 socket really wants to have IPV4
 928  * addresses.
 929  * Returns number of addresses supported.
 930  */
 931 static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
 932                                       __be16 *types)
 933 {
 934         types[0] = SCTP_PARAM_IPV6_ADDRESS;
 935         if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) {
 936                 types[1] = SCTP_PARAM_IPV4_ADDRESS;
 937                 return 2;
 938         }
 939         return 1;
 940 }
 941
 942 static const struct proto_ops inet6_seqpacket_ops = {
 943         .family            = PF_INET6,
 944         .owner             = THIS_MODULE,
 945         .release           = inet6_release,
 946         .bind              = inet6_bind,
 947         .connect           = inet_dgram_connect,
 948         .socketpair        = sock_no_socketpair,
 949         .accept            = inet_accept,
 950         .getname           = inet6_getname,
 951         .poll              = sctp_poll,
 952         .ioctl             = inet6_ioctl,
 953         .listen            = sctp_inet_listen,
 954         .shutdown          = inet_shutdown,
 955         .setsockopt        = sock_common_setsockopt,
 956         .getsockopt        = sock_common_getsockopt,
 957         .sendmsg           = inet_sendmsg,
 958         .recvmsg           = sock_common_recvmsg,
 959         .mmap              = sock_no_mmap,
 960 #ifdef CONFIG_COMPAT
 961         .compat_setsockopt = compat_sock_common_setsockopt,
 962         .compat_getsockopt = compat_sock_common_getsockopt,
 963 #endif
 964 };
 965
 966 static struct inet_protosw sctpv6_seqpacket_protosw = {
 967         .type          = SOCK_SEQPACKET,
 968         .protocol      = IPPROTO_SCTP,
 969         .prot          = &sctpv6_prot,
 970         .ops           = &inet6_seqpacket_ops,
 971         .capability    = -1,
 972         .no_check      = 0,
 973         .flags         = SCTP_PROTOSW_FLAG
 974 };
 975 static struct inet_protosw sctpv6_stream_protosw = {
 976         .type          = SOCK_STREAM,
 977         .protocol      = IPPROTO_SCTP,
 978         .prot          = &sctpv6_prot,
 979         .ops           = &inet6_seqpacket_ops,
 980         .capability    = -1,
 981         .no_check      = 0,
 982         .flags         = SCTP_PROTOSW_FLAG,
 983 };
 984
 985 static int sctp6_rcv(struct sk_buff *skb)
 986 {
 987         return sctp_rcv(skb) ? -1 : 0;
 988 }
 989
 990 static struct inet6_protocol sctpv6_protocol = {
 991         .handler      = sctp6_rcv,
 992         .err_handler  = sctp_v6_err,
 993         .flags        = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
 994 };
 995
 996 static struct sctp_af sctp_af_inet6 = {
 997         .sa_family         = AF_INET6,
 998         .sctp_xmit         = sctp_v6_xmit,
 999         .setsockopt        = ipv6_setsockopt,
1000         .getsockopt        = ipv6_getsockopt,
1001         .get_dst           = sctp_v6_get_dst,
1002         .get_saddr         = sctp_v6_get_saddr,
1003         .copy_addrlist     = sctp_v6_copy_addrlist,
1004         .from_skb          = sctp_v6_from_skb,
1005         .from_sk           = sctp_v6_from_sk,
1006         .to_sk_saddr       = sctp_v6_to_sk_saddr,
1007         .to_sk_daddr       = sctp_v6_to_sk_daddr,
1008         .from_addr_param   = sctp_v6_from_addr_param,
1009         .to_addr_param     = sctp_v6_to_addr_param,
1010         .dst_saddr         = sctp_v6_dst_saddr,
1011         .cmp_addr          = sctp_v6_cmp_addr,
1012         .scope             = sctp_v6_scope,
1013         .addr_valid        = sctp_v6_addr_valid,
1014         .inaddr_any        = sctp_v6_inaddr_any,
1015         .is_any            = sctp_v6_is_any,
1016         .available         = sctp_v6_available,
1017         .skb_iif           = sctp_v6_skb_iif,
1018         .is_ce             = sctp_v6_is_ce,
1019         .seq_dump_addr     = sctp_v6_seq_dump_addr,
1020         .ecn_capable       = sctp_v6_ecn_capable,
1021         .net_header_len    = sizeof(struct ipv6hdr),
1022         .sockaddr_len      = sizeof(struct sockaddr_in6),
1023 #ifdef CONFIG_COMPAT
1024         .compat_setsockopt = compat_ipv6_setsockopt,
1025         .compat_getsockopt = compat_ipv6_getsockopt,
1026 #endif
1027 };
1028
1029 static struct sctp_pf sctp_pf_inet6 = {
1030         .event_msgname = sctp_inet6_event_msgname,
1031         .skb_msgname   = sctp_inet6_skb_msgname,
1032         .af_supported  = sctp_inet6_af_supported,
1033         .cmp_addr      = sctp_inet6_cmp_addr,
1034         .bind_verify   = sctp_inet6_bind_verify,
1035         .send_verify   = sctp_inet6_send_verify,
1036         .supported_addrs = sctp_inet6_supported_addrs,
1037         .create_accept_sk = sctp_v6_create_accept_sk,
1038         .addr_v4map    = sctp_v6_addr_v4map,
1039         .af            = &sctp_af_inet6,
1040 };
1041
1042 /* Initialize IPv6 support and register with socket layer.  */
1043 void sctp_v6_pf_init(void)
1044 {
1045         /* Register the SCTP specific PF_INET6 functions. */
1046         sctp_register_pf(&sctp_pf_inet6, PF_INET6);
1047
1048         /* Register the SCTP specific AF_INET6 functions. */
1049         sctp_register_af(&sctp_af_inet6);
1050 }
1051
1052 void sctp_v6_pf_exit(void)
1053 {
1054         list_del(&sctp_af_inet6.list);
1055 }
1056
1057 /* Initialize IPv6 support and register with socket layer.  */
1058 int sctp_v6_protosw_init(void)
1059 {
1060         int rc;
1061
1062         rc = proto_register(&sctpv6_prot, 1);
1063         if (rc)
1064                 return rc;
1065
1066         /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
1067         inet6_register_protosw(&sctpv6_seqpacket_protosw);
1068         inet6_register_protosw(&sctpv6_stream_protosw);
1069
1070         return 0;
1071 }
1072
1073 void sctp_v6_protosw_exit(void)
1074 {
1075         inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
1076         inet6_unregister_protosw(&sctpv6_stream_protosw);
1077         proto_unregister(&sctpv6_prot);
1078 }
1079
1080
1081 /* Register with inet6 layer. */
1082 int sctp_v6_add_protocol(void)
1083 {
1084         /* Register notifier for inet6 address additions/deletions. */
1085         register_inet6addr_notifier(&sctp_inet6addr_notifier);
1086
1087         if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
1088                 return -EAGAIN;
1089
1090         return 0;
1091 }
1092
1093 /* Unregister with inet6 layer. */
1094 void sctp_v6_del_protocol(void)
1095 {
1096         inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
1097         unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1098 }