net/sctp/ipv6.c

   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/sched.h>
  57 #include <linux/in.h>
  58 #include <linux/in6.h>
  59 #include <linux/netdevice.h>
  60 #include <linux/init.h>
  61 #include <linux/ipsec.h>
  62
  63 #include <linux/ipv6.h>
  64 #include <linux/icmpv6.h>
  65 #include <linux/random.h>
  66 #include <linux/seq_file.h>
  67
  68 #include <net/protocol.h>
  69 #include <net/ndisc.h>
  70 #include <net/ip.h>
  71 #include <net/ipv6.h>
  72 #include <net/transp_v6.h>
  73 #include <net/addrconf.h>
  74 #include <net/ip6_route.h>
  75 #include <net/inet_common.h>
  76 #include <net/inet_ecn.h>
  77 #include <net/sctp/sctp.h>
  78
  79 #include <asm/uaccess.h>
  80
  81 extern int sctp_inetaddr_event(struct notifier_block *, unsigned long, void *);
  82 static struct notifier_block sctp_inet6addr_notifier = {
  83         .notifier_call = sctp_inetaddr_event,
  84 };
  85
  86 /* ICMP error handler. */
  87 SCTP_STATIC void sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
  88                              int type, int code, int offset, __u32 info)
  89 {
  90         struct inet6_dev *idev;
  91         struct ipv6hdr *iph = (struct ipv6hdr *)skb->data;
  92         struct sctphdr *sh = (struct sctphdr *)(skb->data + offset);
  93         struct sock *sk;
  94         struct sctp_association *asoc;
  95         struct sctp_transport *transport;
  96         struct ipv6_pinfo *np;
  97         char *saveip, *savesctp;
  98         int err;
  99
 100         idev = in6_dev_get(skb->dev);
 101
 102         /* Fix up skb to look at the embedded net header. */
 103         saveip = skb->nh.raw;
 104         savesctp  = skb->h.raw;
 105         skb->nh.ipv6h = iph;
 106         skb->h.raw = (char *)sh;
 107         sk = sctp_err_lookup(AF_INET6, skb, sh, &asoc, &transport);
 108         /* Put back, the original pointers. */
 109         skb->nh.raw = saveip;
 110         skb->h.raw = savesctp;
 111         if (!sk) {
 112                 ICMP6_INC_STATS_BH(idev, ICMP6_MIB_INERRORS);
 113                 goto out;
 114         }
 115
 116         /* Warning:  The sock lock is held.  Remember to call
 117          * sctp_err_finish!
 118          */
 119
 120         switch (type) {
 121         case ICMPV6_PKT_TOOBIG:
 122                 sctp_icmp_frag_needed(sk, asoc, transport, ntohl(info));
 123                 goto out_unlock;
 124         case ICMPV6_PARAMPROB:
 125                 if (ICMPV6_UNK_NEXTHDR == code) {
 126                         sctp_icmp_proto_unreachable(sk, asoc, transport);
 127                         goto out_unlock;
 128                 }
 129                 break;
 130         default:
 131                 break;
 132         }
 133
 134         np = inet6_sk(sk);
 135         icmpv6_err_convert(type, code, &err);
 136         if (!sock_owned_by_user(sk) && np->recverr) {
 137                 sk->sk_err = err;
 138                 sk->sk_error_report(sk);
 139         } else {  /* Only an error on timeout */
 140                 sk->sk_err_soft = err;
 141         }
 142
 143 out_unlock:
 144         sctp_err_finish(sk, asoc);
 145 out:
 146         if (likely(idev != NULL))
 147                 in6_dev_put(idev);
 148 }
 149
 150 /* Based on tcp_v6_xmit() in tcp_ipv6.c. */
 151 static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *transport,
 152                         int ipfragok)
 153 {
 154         struct sock *sk = skb->sk;
 155         struct ipv6_pinfo *np = inet6_sk(sk);
 156         struct flowi fl;
 157
 158         memset(&fl, 0, sizeof(fl));
 159
 160         fl.proto = sk->sk_protocol;
 161
 162         /* Fill in the dest address from the route entry passed with the skb
 163          * and the source address from the transport.
 164          */
 165         ipv6_addr_copy(&fl.fl6_dst, &transport->ipaddr.v6.sin6_addr);
 166         ipv6_addr_copy(&fl.fl6_src, &transport->saddr.v6.sin6_addr);
 167
 168         fl.fl6_flowlabel = np->flow_label;
 169         IP6_ECN_flow_xmit(sk, fl.fl6_flowlabel);
 170         if (ipv6_addr_type(&fl.fl6_src) & IPV6_ADDR_LINKLOCAL)
 171                 fl.oif = transport->saddr.v6.sin6_scope_id;
 172         else
 173                 fl.oif = sk->sk_bound_dev_if;
 174         fl.fl_ip_sport = inet_sk(sk)->sport;
 175         fl.fl_ip_dport = transport->ipaddr.v6.sin6_port;
 176
 177         if (np->opt && np->opt->srcrt) {
 178                 struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
 179                 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
 180         }
 181
 182         SCTP_DEBUG_PRINTK("%s: skb:%p, len:%d, "
 183                           "src:" NIP6_FMT " dst:" NIP6_FMT "\n",
 184                           __FUNCTION__, skb, skb->len,
 185                           NIP6(fl.fl6_src), NIP6(fl.fl6_dst));
 186
 187         SCTP_INC_STATS(SCTP_MIB_OUTSCTPPACKS);
 188
 189         return ip6_xmit(sk, skb, &fl, np->opt, ipfragok);
 190 }
 191
 192 /* Returns the dst cache entry for the given source and destination ip
 193  * addresses.
 194  */
 195 static struct dst_entry *sctp_v6_get_dst(struct sctp_association *asoc,
 196                                          union sctp_addr *daddr,
 197                                          union sctp_addr *saddr)
 198 {
 199         struct dst_entry *dst;
 200         struct flowi fl;
 201
 202         memset(&fl, 0, sizeof(fl));
 203         ipv6_addr_copy(&fl.fl6_dst, &daddr->v6.sin6_addr);
 204         if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
 205                 fl.oif = daddr->v6.sin6_scope_id;
 206
 207
 208         SCTP_DEBUG_PRINTK("%s: DST=" NIP6_FMT " ",
 209                           __FUNCTION__, NIP6(fl.fl6_dst));
 210
 211         if (saddr) {
 212                 ipv6_addr_copy(&fl.fl6_src, &saddr->v6.sin6_addr);
 213                 SCTP_DEBUG_PRINTK(
 214                         "SRC=" NIP6_FMT " - ",
 215                         NIP6(fl.fl6_src));
 216         }
 217
 218         dst = ip6_route_output(NULL, &fl);
 219         if (dst) {
 220                 struct rt6_info *rt;
 221                 rt = (struct rt6_info *)dst;
 222                 SCTP_DEBUG_PRINTK(
 223                         "rt6_dst:" NIP6_FMT " rt6_src:" NIP6_FMT "\n",
 224                         NIP6(rt->rt6i_dst.addr), NIP6(rt->rt6i_src.addr));
 225         } else {
 226                 SCTP_DEBUG_PRINTK("NO ROUTE\n");
 227         }
 228
 229         return dst;
 230 }
 231
 232 /* Returns the number of consecutive initial bits that match in the 2 ipv6
 233  * addresses.
 234  */
 235 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
 236                                          union sctp_addr *s2)
 237 {
 238         struct in6_addr *a1 = &s1->v6.sin6_addr;
 239         struct in6_addr *a2 = &s2->v6.sin6_addr;
 240         int i, j;
 241
 242         for (i = 0; i < 4 ; i++) {
 243                 __u32 a1xora2;
 244
 245                 a1xora2 = a1->s6_addr32[i] ^ a2->s6_addr32[i];
 246
 247                 if ((j = fls(ntohl(a1xora2))))
 248                         return (i * 32 + 32 - j);
 249         }
 250
 251         return (i*32);
 252 }
 253
 254 /* Fills in the source address(saddr) based on the destination address(daddr)
 255  * and asoc's bind address list.
 256  */
 257 static void sctp_v6_get_saddr(struct sctp_association *asoc,
 258                               struct dst_entry *dst,
 259                               union sctp_addr *daddr,
 260                               union sctp_addr *saddr)
 261 {
 262         struct sctp_bind_addr *bp;
 263         rwlock_t *addr_lock;
 264         struct sctp_sockaddr_entry *laddr;
 265         struct list_head *pos;
 266         sctp_scope_t scope;
 267         union sctp_addr *baddr = NULL;
 268         __u8 matchlen = 0;
 269         __u8 bmatchlen;
 270
 271         SCTP_DEBUG_PRINTK("%s: asoc:%p dst:%p "
 272                           "daddr:" NIP6_FMT " ",
 273                           __FUNCTION__, asoc, dst, NIP6(daddr->v6.sin6_addr));
 274
 275         if (!asoc) {
 276                 ipv6_get_saddr(dst, &daddr->v6.sin6_addr,&saddr->v6.sin6_addr);
 277                 SCTP_DEBUG_PRINTK("saddr from ipv6_get_saddr: " NIP6_FMT "\n",
 278                                   NIP6(saddr->v6.sin6_addr));
 279                 return;
 280         }
 281
 282         scope = sctp_scope(daddr);
 283
 284         bp = &asoc->base.bind_addr;
 285         addr_lock = &asoc->base.addr_lock;
 286
 287         /* Go through the bind address list and find the best source address
 288          * that matches the scope of the destination address.
 289          */
 290         sctp_read_lock(addr_lock);
 291         list_for_each(pos, &bp->address_list) {
 292                 laddr = list_entry(pos, struct sctp_sockaddr_entry, list);
 293                 if ((laddr->a.sa.sa_family == AF_INET6) &&
 294                     (scope <= sctp_scope(&laddr->a))) {
 295                         bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
 296                         if (!baddr || (matchlen < bmatchlen)) {
 297                                 baddr = &laddr->a;
 298                                 matchlen = bmatchlen;
 299                         }
 300                 }
 301         }
 302
 303         if (baddr) {
 304                 memcpy(saddr, baddr, sizeof(union sctp_addr));
 305                 SCTP_DEBUG_PRINTK("saddr: " NIP6_FMT "\n",
 306                                   NIP6(saddr->v6.sin6_addr));
 307         } else {
 308                 printk(KERN_ERR "%s: asoc:%p Could not find a valid source "
 309                        "address for the dest:" NIP6_FMT "\n",
 310                        __FUNCTION__, asoc, NIP6(daddr->v6.sin6_addr));
 311         }
 312
 313         sctp_read_unlock(addr_lock);
 314 }
 315
 316 /* Make a copy of all potential local addresses. */
 317 static void sctp_v6_copy_addrlist(struct list_head *addrlist,
 318                                   struct net_device *dev)
 319 {
 320         struct inet6_dev *in6_dev;
 321         struct inet6_ifaddr *ifp;
 322         struct sctp_sockaddr_entry *addr;
 323
 324         read_lock(&addrconf_lock);
 325         if ((in6_dev = __in6_dev_get(dev)) == NULL) {
 326                 read_unlock(&addrconf_lock);
 327                 return;
 328         }
 329
 330         read_lock(&in6_dev->lock);
 331         for (ifp = in6_dev->addr_list; ifp; ifp = ifp->if_next) {
 332                 /* Add the address to the local list.  */
 333                 addr = t_new(struct sctp_sockaddr_entry, GFP_ATOMIC);
 334                 if (addr) {
 335                         addr->a.v6.sin6_family = AF_INET6;
 336                         addr->a.v6.sin6_port = 0;
 337                         addr->a.v6.sin6_addr = ifp->addr;
 338                         addr->a.v6.sin6_scope_id = dev->ifindex;
 339                         INIT_LIST_HEAD(&addr->list);
 340                         list_add_tail(&addr->list, addrlist);
 341                 }
 342         }
 343
 344         read_unlock(&in6_dev->lock);
 345         read_unlock(&addrconf_lock);
 346 }
 347
 348 /* Initialize a sockaddr_storage from in incoming skb. */
 349 static void sctp_v6_from_skb(union sctp_addr *addr,struct sk_buff *skb,
 350                              int is_saddr)
 351 {
 352         void *from;
 353         __u16 *port;
 354         struct sctphdr *sh;
 355
 356         port = &addr->v6.sin6_port;
 357         addr->v6.sin6_family = AF_INET6;
 358         addr->v6.sin6_flowinfo = 0; /* FIXME */
 359         addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif;
 360
 361         sh = (struct sctphdr *) skb->h.raw;
 362         if (is_saddr) {
 363                 *port  = ntohs(sh->source);
 364                 from = &skb->nh.ipv6h->saddr;
 365         } else {
 366                 *port = ntohs(sh->dest);
 367                 from = &skb->nh.ipv6h->daddr;
 368         }
 369         ipv6_addr_copy(&addr->v6.sin6_addr, from);
 370 }
 371
 372 /* Initialize an sctp_addr from a socket. */
 373 static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
 374 {
 375         addr->v6.sin6_family = AF_INET6;
 376         addr->v6.sin6_port = inet_sk(sk)->num;
 377         addr->v6.sin6_addr = inet6_sk(sk)->rcv_saddr;
 378 }
 379
 380 /* Initialize sk->sk_rcv_saddr from sctp_addr. */
 381 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
 382 {
 383         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
 384                 inet6_sk(sk)->rcv_saddr.s6_addr32[0] = 0;
 385                 inet6_sk(sk)->rcv_saddr.s6_addr32[1] = 0;
 386                 inet6_sk(sk)->rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
 387                 inet6_sk(sk)->rcv_saddr.s6_addr32[3] =
 388                         addr->v4.sin_addr.s_addr;
 389         } else {
 390                 inet6_sk(sk)->rcv_saddr = addr->v6.sin6_addr;
 391         }
 392 }
 393
 394 /* Initialize sk->sk_daddr from sctp_addr. */
 395 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
 396 {
 397         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
 398                 inet6_sk(sk)->daddr.s6_addr32[0] = 0;
 399                 inet6_sk(sk)->daddr.s6_addr32[1] = 0;
 400                 inet6_sk(sk)->daddr.s6_addr32[2] = htonl(0x0000ffff);
 401                 inet6_sk(sk)->daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
 402         } else {
 403                 inet6_sk(sk)->daddr = addr->v6.sin6_addr;
 404         }
 405 }
 406
 407 /* Initialize a sctp_addr from an address parameter. */
 408 static void sctp_v6_from_addr_param(union sctp_addr *addr,
 409                                     union sctp_addr_param *param,
 410                                     __u16 port, int iif)
 411 {
 412         addr->v6.sin6_family = AF_INET6;
 413         addr->v6.sin6_port = port;
 414         addr->v6.sin6_flowinfo = 0; /* BUG */
 415         ipv6_addr_copy(&addr->v6.sin6_addr, &param->v6.addr);
 416         addr->v6.sin6_scope_id = iif;
 417 }
 418
 419 /* Initialize an address parameter from a sctp_addr and return the length
 420  * of the address parameter.
 421  */
 422 static int sctp_v6_to_addr_param(const union sctp_addr *addr,
 423                                  union sctp_addr_param *param)
 424 {
 425         int length = sizeof(sctp_ipv6addr_param_t);
 426
 427         param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
 428         param->v6.param_hdr.length = ntohs(length);
 429         ipv6_addr_copy(&param->v6.addr, &addr->v6.sin6_addr);
 430
 431         return length;
 432 }
 433
 434 /* Initialize a sctp_addr from a dst_entry. */
 435 static void sctp_v6_dst_saddr(union sctp_addr *addr, struct dst_entry *dst,
 436                               unsigned short port)
 437 {
 438         struct rt6_info *rt = (struct rt6_info *)dst;
 439         addr->sa.sa_family = AF_INET6;
 440         addr->v6.sin6_port = port;
 441         ipv6_addr_copy(&addr->v6.sin6_addr, &rt->rt6i_src.addr);
 442 }
 443
 444 /* Compare addresses exactly.
 445  * v4-mapped-v6 is also in consideration.
 446  */
 447 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
 448                             const union sctp_addr *addr2)
 449 {
 450         if (addr1->sa.sa_family != addr2->sa.sa_family) {
 451                 if (addr1->sa.sa_family == AF_INET &&
 452                     addr2->sa.sa_family == AF_INET6 &&
 453                     IPV6_ADDR_MAPPED == ipv6_addr_type(&addr2->v6.sin6_addr)) {
 454                         if (addr2->v6.sin6_port == addr1->v4.sin_port &&
 455                             addr2->v6.sin6_addr.s6_addr32[3] ==
 456                             addr1->v4.sin_addr.s_addr)
 457                                 return 1;
 458                 }
 459                 if (addr2->sa.sa_family == AF_INET &&
 460                     addr1->sa.sa_family == AF_INET6 &&
 461                     IPV6_ADDR_MAPPED == ipv6_addr_type(&addr1->v6.sin6_addr)) {
 462                         if (addr1->v6.sin6_port == addr2->v4.sin_port &&
 463                             addr1->v6.sin6_addr.s6_addr32[3] ==
 464                             addr2->v4.sin_addr.s_addr)
 465                                 return 1;
 466                 }
 467                 return 0;
 468         }
 469         if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
 470                 return 0;
 471         /* If this is a linklocal address, compare the scope_id. */
 472         if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) {
 473                 if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
 474                     (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) {
 475                         return 0;
 476                 }
 477         }
 478
 479         return 1;
 480 }
 481
 482 /* Initialize addr struct to INADDR_ANY. */
 483 static void sctp_v6_inaddr_any(union sctp_addr *addr, unsigned short port)
 484 {
 485         memset(addr, 0x00, sizeof(union sctp_addr));
 486         addr->v6.sin6_family = AF_INET6;
 487         addr->v6.sin6_port = port;
 488 }
 489
 490 /* Is this a wildcard address? */
 491 static int sctp_v6_is_any(const union sctp_addr *addr)
 492 {
 493         return ipv6_addr_any(&addr->v6.sin6_addr);
 494 }
 495
 496 /* Should this be available for binding?   */
 497 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
 498 {
 499         int type;
 500         struct in6_addr *in6 = (struct in6_addr *)&addr->v6.sin6_addr;
 501
 502         type = ipv6_addr_type(in6);
 503         if (IPV6_ADDR_ANY == type)
 504                 return 1;
 505         if (type == IPV6_ADDR_MAPPED) {
 506                 if (sp && !sp->v4mapped)
 507                         return 0;
 508                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
 509                         return 0;
 510                 sctp_v6_map_v4(addr);
 511                 return sctp_get_af_specific(AF_INET)->available(addr, sp);
 512         }
 513         if (!(type & IPV6_ADDR_UNICAST))
 514                 return 0;
 515
 516         return ipv6_chk_addr(in6, NULL, 0);
 517 }
 518
 519 /* This function checks if the address is a valid address to be used for
 520  * SCTP.
 521  *
 522  * Output:
 523  * Return 0 - If the address is a non-unicast or an illegal address.
 524  * Return 1 - If the address is a unicast.
 525  */
 526 static int sctp_v6_addr_valid(union sctp_addr *addr,
 527                               struct sctp_sock *sp,
 528                               const struct sk_buff *skb)
 529 {
 530         int ret = ipv6_addr_type(&addr->v6.sin6_addr);
 531
 532         /* Support v4-mapped-v6 address. */
 533         if (ret == IPV6_ADDR_MAPPED) {
 534                 /* Note: This routine is used in input, so v4-mapped-v6
 535                  * are disallowed here when there is no sctp_sock.
 536                  */
 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)->addr_valid(addr, sp, skb);
 543         }
 544
 545         /* Is this a non-unicast address */
 546         if (!(ret & IPV6_ADDR_UNICAST))
 547                 return 0;
 548
 549         return 1;
 550 }
 551
 552 /* What is the scope of 'addr'?  */
 553 static sctp_scope_t sctp_v6_scope(union sctp_addr *addr)
 554 {
 555         int v6scope;
 556         sctp_scope_t retval;
 557
 558         /* The IPv6 scope is really a set of bit fields.
 559          * See IFA_* in <net/if_inet6.h>.  Map to a generic SCTP scope.
 560          */
 561
 562         v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
 563         switch (v6scope) {
 564         case IFA_HOST:
 565                 retval = SCTP_SCOPE_LOOPBACK;
 566                 break;
 567         case IFA_LINK:
 568                 retval = SCTP_SCOPE_LINK;
 569                 break;
 570         case IFA_SITE:
 571                 retval = SCTP_SCOPE_PRIVATE;
 572                 break;
 573         default:
 574                 retval = SCTP_SCOPE_GLOBAL;
 575                 break;
 576         };
 577
 578         return retval;
 579 }
 580
 581 /* Create and initialize a new sk for the socket to be returned by accept(). */
 582 static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
 583                                              struct sctp_association *asoc)
 584 {
 585         struct inet_sock *inet = inet_sk(sk);
 586         struct sock *newsk;
 587         struct inet_sock *newinet;
 588         struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
 589         struct sctp6_sock *newsctp6sk;
 590
 591         newsk = sk_alloc(PF_INET6, GFP_KERNEL, sk->sk_prot, 1);
 592         if (!newsk)
 593                 goto out;
 594
 595         sock_init_data(NULL, newsk);
 596
 597         newsk->sk_type = SOCK_STREAM;
 598
 599         newsk->sk_prot = sk->sk_prot;
 600         newsk->sk_no_check = sk->sk_no_check;
 601         newsk->sk_reuse = sk->sk_reuse;
 602
 603         newsk->sk_destruct = inet_sock_destruct;
 604         newsk->sk_family = PF_INET6;
 605         newsk->sk_protocol = IPPROTO_SCTP;
 606         newsk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
 607         newsk->sk_shutdown = sk->sk_shutdown;
 608         sock_reset_flag(sk, SOCK_ZAPPED);
 609
 610         newsctp6sk = (struct sctp6_sock *)newsk;
 611         inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
 612
 613         newinet = inet_sk(newsk);
 614         newnp = inet6_sk(newsk);
 615
 616         memcpy(newnp, np, sizeof(struct ipv6_pinfo));
 617
 618         /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
 619          * and getpeername().
 620          */
 621         newinet->sport = inet->sport;
 622         newnp->saddr = np->saddr;
 623         newnp->rcv_saddr = np->rcv_saddr;
 624         newinet->dport = htons(asoc->peer.port);
 625         sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
 626
 627         /* Init the ipv4 part of the socket since we can have sockets
 628          * using v6 API for ipv4.
 629          */
 630         newinet->uc_ttl = -1;
 631         newinet->mc_loop = 1;
 632         newinet->mc_ttl = 1;
 633         newinet->mc_index = 0;
 634         newinet->mc_list = NULL;
 635
 636         if (ipv4_config.no_pmtu_disc)
 637                 newinet->pmtudisc = IP_PMTUDISC_DONT;
 638         else
 639                 newinet->pmtudisc = IP_PMTUDISC_WANT;
 640
 641         sk_refcnt_debug_inc(newsk);
 642
 643         if (newsk->sk_prot->init(newsk)) {
 644                 sk_common_release(newsk);
 645                 newsk = NULL;
 646         }
 647
 648 out:
 649         return newsk;
 650 }
 651
 652 /* Map v4 address to mapped v6 address */
 653 static void sctp_v6_addr_v4map(struct sctp_sock *sp, union sctp_addr *addr)
 654 {
 655         if (sp->v4mapped && AF_INET == addr->sa.sa_family)
 656                 sctp_v4_map_v6(addr);
 657 }
 658
 659 /* Where did this skb come from?  */
 660 static int sctp_v6_skb_iif(const struct sk_buff *skb)
 661 {
 662         struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb;
 663         return opt->iif;
 664 }
 665
 666 /* Was this packet marked by Explicit Congestion Notification? */
 667 static int sctp_v6_is_ce(const struct sk_buff *skb)
 668 {
 669         return *((__u32 *)(skb->nh.ipv6h)) & htonl(1<<20);
 670 }
 671
 672 /* Dump the v6 addr to the seq file. */
 673 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
 674 {
 675         seq_printf(seq, NIP6_FMT " ", NIP6(addr->v6.sin6_addr));
 676 }
 677
 678 /* Initialize a PF_INET6 socket msg_name. */
 679 static void sctp_inet6_msgname(char *msgname, int *addr_len)
 680 {
 681         struct sockaddr_in6 *sin6;
 682
 683         sin6 = (struct sockaddr_in6 *)msgname;
 684         sin6->sin6_family = AF_INET6;
 685         sin6->sin6_flowinfo = 0;
 686         sin6->sin6_scope_id = 0; /*FIXME */
 687         *addr_len = sizeof(struct sockaddr_in6);
 688 }
 689
 690 /* Initialize a PF_INET msgname from a ulpevent. */
 691 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
 692                                      char *msgname, int *addrlen)
 693 {
 694         struct sockaddr_in6 *sin6, *sin6from;
 695
 696         if (msgname) {
 697                 union sctp_addr *addr;
 698                 struct sctp_association *asoc;
 699
 700                 asoc = event->asoc;
 701                 sctp_inet6_msgname(msgname, addrlen);
 702                 sin6 = (struct sockaddr_in6 *)msgname;
 703                 sin6->sin6_port = htons(asoc->peer.port);
 704                 addr = &asoc->peer.primary_addr;
 705
 706                 /* Note: If we go to a common v6 format, this code
 707                  * will change.
 708                  */
 709
 710                 /* Map ipv4 address into v4-mapped-on-v6 address.  */
 711                 if (sctp_sk(asoc->base.sk)->v4mapped &&
 712                     AF_INET == addr->sa.sa_family) {
 713                         sctp_v4_map_v6((union sctp_addr *)sin6);
 714                         sin6->sin6_addr.s6_addr32[3] =
 715                                 addr->v4.sin_addr.s_addr;
 716                         return;
 717                 }
 718
 719                 sin6from = &asoc->peer.primary_addr.v6;
 720                 ipv6_addr_copy(&sin6->sin6_addr, &sin6from->sin6_addr);
 721                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 722                         sin6->sin6_scope_id = sin6from->sin6_scope_id;
 723         }
 724 }
 725
 726 /* Initialize a msg_name from an inbound skb. */
 727 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
 728                                    int *addr_len)
 729 {
 730         struct sctphdr *sh;
 731         struct sockaddr_in6 *sin6;
 732
 733         if (msgname) {
 734                 sctp_inet6_msgname(msgname, addr_len);
 735                 sin6 = (struct sockaddr_in6 *)msgname;
 736                 sh = (struct sctphdr *)skb->h.raw;
 737                 sin6->sin6_port = sh->source;
 738
 739                 /* Map ipv4 address into v4-mapped-on-v6 address. */
 740                 if (sctp_sk(skb->sk)->v4mapped &&
 741                     skb->nh.iph->version == 4) {
 742                         sctp_v4_map_v6((union sctp_addr *)sin6);
 743                         sin6->sin6_addr.s6_addr32[3] = skb->nh.iph->saddr;
 744                         return;
 745                 }
 746
 747                 /* Otherwise, just copy the v6 address. */
 748                 ipv6_addr_copy(&sin6->sin6_addr, &skb->nh.ipv6h->saddr);
 749                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) {
 750                         struct sctp_ulpevent *ev = sctp_skb2event(skb);
 751                         sin6->sin6_scope_id = ev->iif;
 752                 }
 753         }
 754 }
 755
 756 /* Do we support this AF? */
 757 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
 758 {
 759         switch (family) {
 760         case AF_INET6:
 761                 return 1;
 762         /* v4-mapped-v6 addresses */
 763         case AF_INET:
 764                 if (!__ipv6_only_sock(sctp_opt2sk(sp)) && sp->v4mapped)
 765                         return 1;
 766         default:
 767                 return 0;
 768         }
 769 }
 770
 771 /* Address matching with wildcards allowed.  This extra level
 772  * of indirection lets us choose whether a PF_INET6 should
 773  * disallow any v4 addresses if we so choose.
 774  */
 775 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
 776                                const union sctp_addr *addr2,
 777                                struct sctp_sock *opt)
 778 {
 779         struct sctp_af *af1, *af2;
 780
 781         af1 = sctp_get_af_specific(addr1->sa.sa_family);
 782         af2 = sctp_get_af_specific(addr2->sa.sa_family);
 783
 784         if (!af1 || !af2)
 785                 return 0;
 786         /* Today, wildcard AF_INET/AF_INET6. */
 787         if (sctp_is_any(addr1) || sctp_is_any(addr2))
 788                 return 1;
 789
 790         if (addr1->sa.sa_family != addr2->sa.sa_family)
 791                 return 0;
 792
 793         return af1->cmp_addr(addr1, addr2);
 794 }
 795
 796 /* Verify that the provided sockaddr looks bindable.   Common verification,
 797  * has already been taken care of.
 798  */
 799 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
 800 {
 801         struct sctp_af *af;
 802
 803         /* ASSERT: address family has already been verified. */
 804         if (addr->sa.sa_family != AF_INET6)
 805                 af = sctp_get_af_specific(addr->sa.sa_family);
 806         else {
 807                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
 808                 struct net_device *dev;
 809
 810                 if (type & IPV6_ADDR_LINKLOCAL) {
 811                         if (!addr->v6.sin6_scope_id)
 812                                 return 0;
 813                         dev = dev_get_by_index(addr->v6.sin6_scope_id);
 814                         if (!dev)
 815                                 return 0;
 816                         dev_put(dev);
 817                 }
 818                 af = opt->pf->af;
 819         }
 820         return af->available(addr, opt);
 821 }
 822
 823 /* Verify that the provided sockaddr looks sendable.   Common verification,
 824  * has already been taken care of.
 825  */
 826 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
 827 {
 828         struct sctp_af *af = NULL;
 829
 830         /* ASSERT: address family has already been verified. */
 831         if (addr->sa.sa_family != AF_INET6)
 832                 af = sctp_get_af_specific(addr->sa.sa_family);
 833         else {
 834                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
 835                 struct net_device *dev;
 836
 837                 if (type & IPV6_ADDR_LINKLOCAL) {
 838                         if (!addr->v6.sin6_scope_id)
 839                                 return 0;
 840                         dev = dev_get_by_index(addr->v6.sin6_scope_id);
 841                         if (!dev)
 842                                 return 0;
 843                         dev_put(dev);
 844                 }
 845                 af = opt->pf->af;
 846         }
 847
 848         return af != NULL;
 849 }
 850
 851 /* Fill in Supported Address Type information for INIT and INIT-ACK
 852  * chunks.   Note: In the future, we may want to look at sock options
 853  * to determine whether a PF_INET6 socket really wants to have IPV4
 854  * addresses.
 855  * Returns number of addresses supported.
 856  */
 857 static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
 858                                       __u16 *types)
 859 {
 860         types[0] = SCTP_PARAM_IPV4_ADDRESS;
 861         types[1] = SCTP_PARAM_IPV6_ADDRESS;
 862         return 2;
 863 }
 864
 865 static const struct proto_ops inet6_seqpacket_ops = {
 866         .family            = PF_INET6,
 867         .owner             = THIS_MODULE,
 868         .release           = inet6_release,
 869         .bind              = inet6_bind,
 870         .connect           = inet_dgram_connect,
 871         .socketpair        = sock_no_socketpair,
 872         .accept            = inet_accept,
 873         .getname           = inet6_getname,
 874         .poll              = sctp_poll,
 875         .ioctl             = inet6_ioctl,
 876         .listen            = sctp_inet_listen,
 877         .shutdown          = inet_shutdown,
 878         .setsockopt        = sock_common_setsockopt,
 879         .getsockopt        = sock_common_getsockopt,
 880         .sendmsg           = inet_sendmsg,
 881         .recvmsg           = sock_common_recvmsg,
 882         .mmap              = sock_no_mmap,
 883 #ifdef CONFIG_COMPAT
 884         .compat_setsockopt = compat_sock_common_setsockopt,
 885         .compat_getsockopt = compat_sock_common_getsockopt,
 886 #endif
 887 };
 888
 889 static struct inet_protosw sctpv6_seqpacket_protosw = {
 890         .type          = SOCK_SEQPACKET,
 891         .protocol      = IPPROTO_SCTP,
 892         .prot          = &sctpv6_prot,
 893         .ops           = &inet6_seqpacket_ops,
 894         .capability    = -1,
 895         .no_check      = 0,
 896         .flags         = SCTP_PROTOSW_FLAG
 897 };
 898 static struct inet_protosw sctpv6_stream_protosw = {
 899         .type          = SOCK_STREAM,
 900         .protocol      = IPPROTO_SCTP,
 901         .prot          = &sctpv6_prot,
 902         .ops           = &inet6_seqpacket_ops,
 903         .capability    = -1,
 904         .no_check      = 0,
 905         .flags         = SCTP_PROTOSW_FLAG,
 906 };
 907
 908 static int sctp6_rcv(struct sk_buff **pskb)
 909 {
 910         return sctp_rcv(*pskb) ? -1 : 0;
 911 }
 912
 913 static struct inet6_protocol sctpv6_protocol = {
 914         .handler      = sctp6_rcv,
 915         .err_handler  = sctp_v6_err,
 916         .flags        = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
 917 };
 918
 919 static struct sctp_af sctp_ipv6_specific = {
 920         .sa_family         = AF_INET6,
 921         .sctp_xmit         = sctp_v6_xmit,
 922         .setsockopt        = ipv6_setsockopt,
 923         .getsockopt        = ipv6_getsockopt,
 924         .get_dst           = sctp_v6_get_dst,
 925         .get_saddr         = sctp_v6_get_saddr,
 926         .copy_addrlist     = sctp_v6_copy_addrlist,
 927         .from_skb          = sctp_v6_from_skb,
 928         .from_sk           = sctp_v6_from_sk,
 929         .to_sk_saddr       = sctp_v6_to_sk_saddr,
 930         .to_sk_daddr       = sctp_v6_to_sk_daddr,
 931         .from_addr_param   = sctp_v6_from_addr_param,
 932         .to_addr_param     = sctp_v6_to_addr_param,
 933         .dst_saddr         = sctp_v6_dst_saddr,
 934         .cmp_addr          = sctp_v6_cmp_addr,
 935         .scope             = sctp_v6_scope,
 936         .addr_valid        = sctp_v6_addr_valid,
 937         .inaddr_any        = sctp_v6_inaddr_any,
 938         .is_any            = sctp_v6_is_any,
 939         .available         = sctp_v6_available,
 940         .skb_iif           = sctp_v6_skb_iif,
 941         .is_ce             = sctp_v6_is_ce,
 942         .seq_dump_addr     = sctp_v6_seq_dump_addr,
 943         .net_header_len    = sizeof(struct ipv6hdr),
 944         .sockaddr_len      = sizeof(struct sockaddr_in6),
 945 #ifdef CONFIG_COMPAT
 946         .compat_setsockopt = compat_ipv6_setsockopt,
 947         .compat_getsockopt = compat_ipv6_getsockopt,
 948 #endif
 949 };
 950
 951 static struct sctp_pf sctp_pf_inet6_specific = {
 952         .event_msgname = sctp_inet6_event_msgname,
 953         .skb_msgname   = sctp_inet6_skb_msgname,
 954         .af_supported  = sctp_inet6_af_supported,
 955         .cmp_addr      = sctp_inet6_cmp_addr,
 956         .bind_verify   = sctp_inet6_bind_verify,
 957         .send_verify   = sctp_inet6_send_verify,
 958         .supported_addrs = sctp_inet6_supported_addrs,
 959         .create_accept_sk = sctp_v6_create_accept_sk,
 960         .addr_v4map    = sctp_v6_addr_v4map,
 961         .af            = &sctp_ipv6_specific,
 962 };
 963
 964 /* Initialize IPv6 support and register with inet6 stack.  */
 965 int sctp_v6_init(void)
 966 {
 967         int rc = proto_register(&sctpv6_prot, 1);
 968
 969         if (rc)
 970                 goto out;
 971         /* Register inet6 protocol. */
 972         rc = -EAGAIN;
 973         if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
 974                 goto out_unregister_sctp_proto;
 975
 976         /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
 977         inet6_register_protosw(&sctpv6_seqpacket_protosw);
 978         inet6_register_protosw(&sctpv6_stream_protosw);
 979
 980         /* Register the SCTP specific PF_INET6 functions. */
 981         sctp_register_pf(&sctp_pf_inet6_specific, PF_INET6);
 982
 983         /* Register the SCTP specific AF_INET6 functions. */
 984         sctp_register_af(&sctp_ipv6_specific);
 985
 986         /* Register notifier for inet6 address additions/deletions. */
 987         register_inet6addr_notifier(&sctp_inet6addr_notifier);
 988         rc = 0;
 989 out:
 990         return rc;
 991 out_unregister_sctp_proto:
 992         proto_unregister(&sctpv6_prot);
 993         goto out;
 994 }
 995
 996 /* IPv6 specific exit support. */
 997 void sctp_v6_exit(void)
 998 {
 999         list_del(&sctp_ipv6_specific.list);
1000         inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
1001         inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
1002         inet6_unregister_protosw(&sctpv6_stream_protosw);
1003         unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1004         proto_unregister(&sctpv6_prot);
1005 }