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->use_as_src) &&
 294                     (laddr->a.sa.sa_family == AF_INET6) &&
 295                     (scope <= sctp_scope(&laddr->a))) {
 296                         bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
 297                         if (!baddr || (matchlen < bmatchlen)) {
 298                                 baddr = &laddr->a;
 299                                 matchlen = bmatchlen;
 300                         }
 301                 }
 302         }
 303
 304         if (baddr) {
 305                 memcpy(saddr, baddr, sizeof(union sctp_addr));
 306                 SCTP_DEBUG_PRINTK("saddr: " NIP6_FMT "\n",
 307                                   NIP6(saddr->v6.sin6_addr));
 308         } else {
 309                 printk(KERN_ERR "%s: asoc:%p Could not find a valid source "
 310                        "address for the dest:" NIP6_FMT "\n",
 311                        __FUNCTION__, asoc, NIP6(daddr->v6.sin6_addr));
 312         }
 313
 314         sctp_read_unlock(addr_lock);
 315 }
 316
 317 /* Make a copy of all potential local addresses. */
 318 static void sctp_v6_copy_addrlist(struct list_head *addrlist,
 319                                   struct net_device *dev)
 320 {
 321         struct inet6_dev *in6_dev;
 322         struct inet6_ifaddr *ifp;
 323         struct sctp_sockaddr_entry *addr;
 324
 325         read_lock(&addrconf_lock);
 326         if ((in6_dev = __in6_dev_get(dev)) == NULL) {
 327                 read_unlock(&addrconf_lock);
 328                 return;
 329         }
 330
 331         read_lock(&in6_dev->lock);
 332         for (ifp = in6_dev->addr_list; ifp; ifp = ifp->if_next) {
 333                 /* Add the address to the local list.  */
 334                 addr = t_new(struct sctp_sockaddr_entry, GFP_ATOMIC);
 335                 if (addr) {
 336                         addr->a.v6.sin6_family = AF_INET6;
 337                         addr->a.v6.sin6_port = 0;
 338                         addr->a.v6.sin6_addr = ifp->addr;
 339                         addr->a.v6.sin6_scope_id = dev->ifindex;
 340                         INIT_LIST_HEAD(&addr->list);
 341                         list_add_tail(&addr->list, addrlist);
 342                 }
 343         }
 344
 345         read_unlock(&in6_dev->lock);
 346         read_unlock(&addrconf_lock);
 347 }
 348
 349 /* Initialize a sockaddr_storage from in incoming skb. */
 350 static void sctp_v6_from_skb(union sctp_addr *addr,struct sk_buff *skb,
 351                              int is_saddr)
 352 {
 353         void *from;
 354         __u16 *port;
 355         struct sctphdr *sh;
 356
 357         port = &addr->v6.sin6_port;
 358         addr->v6.sin6_family = AF_INET6;
 359         addr->v6.sin6_flowinfo = 0; /* FIXME */
 360         addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif;
 361
 362         sh = (struct sctphdr *) skb->h.raw;
 363         if (is_saddr) {
 364                 *port  = ntohs(sh->source);
 365                 from = &skb->nh.ipv6h->saddr;
 366         } else {
 367                 *port = ntohs(sh->dest);
 368                 from = &skb->nh.ipv6h->daddr;
 369         }
 370         ipv6_addr_copy(&addr->v6.sin6_addr, from);
 371 }
 372
 373 /* Initialize an sctp_addr from a socket. */
 374 static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
 375 {
 376         addr->v6.sin6_family = AF_INET6;
 377         addr->v6.sin6_port = inet_sk(sk)->num;
 378         addr->v6.sin6_addr = inet6_sk(sk)->rcv_saddr;
 379 }
 380
 381 /* Initialize sk->sk_rcv_saddr from sctp_addr. */
 382 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
 383 {
 384         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
 385                 inet6_sk(sk)->rcv_saddr.s6_addr32[0] = 0;
 386                 inet6_sk(sk)->rcv_saddr.s6_addr32[1] = 0;
 387                 inet6_sk(sk)->rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
 388                 inet6_sk(sk)->rcv_saddr.s6_addr32[3] =
 389                         addr->v4.sin_addr.s_addr;
 390         } else {
 391                 inet6_sk(sk)->rcv_saddr = addr->v6.sin6_addr;
 392         }
 393 }
 394
 395 /* Initialize sk->sk_daddr from sctp_addr. */
 396 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
 397 {
 398         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
 399                 inet6_sk(sk)->daddr.s6_addr32[0] = 0;
 400                 inet6_sk(sk)->daddr.s6_addr32[1] = 0;
 401                 inet6_sk(sk)->daddr.s6_addr32[2] = htonl(0x0000ffff);
 402                 inet6_sk(sk)->daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
 403         } else {
 404                 inet6_sk(sk)->daddr = addr->v6.sin6_addr;
 405         }
 406 }
 407
 408 /* Initialize a sctp_addr from an address parameter. */
 409 static void sctp_v6_from_addr_param(union sctp_addr *addr,
 410                                     union sctp_addr_param *param,
 411                                     __u16 port, int iif)
 412 {
 413         addr->v6.sin6_family = AF_INET6;
 414         addr->v6.sin6_port = port;
 415         addr->v6.sin6_flowinfo = 0; /* BUG */
 416         ipv6_addr_copy(&addr->v6.sin6_addr, &param->v6.addr);
 417         addr->v6.sin6_scope_id = iif;
 418 }
 419
 420 /* Initialize an address parameter from a sctp_addr and return the length
 421  * of the address parameter.
 422  */
 423 static int sctp_v6_to_addr_param(const union sctp_addr *addr,
 424                                  union sctp_addr_param *param)
 425 {
 426         int length = sizeof(sctp_ipv6addr_param_t);
 427
 428         param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
 429         param->v6.param_hdr.length = ntohs(length);
 430         ipv6_addr_copy(&param->v6.addr, &addr->v6.sin6_addr);
 431
 432         return length;
 433 }
 434
 435 /* Initialize a sctp_addr from a dst_entry. */
 436 static void sctp_v6_dst_saddr(union sctp_addr *addr, struct dst_entry *dst,
 437                               unsigned short port)
 438 {
 439         struct rt6_info *rt = (struct rt6_info *)dst;
 440         addr->sa.sa_family = AF_INET6;
 441         addr->v6.sin6_port = port;
 442         ipv6_addr_copy(&addr->v6.sin6_addr, &rt->rt6i_src.addr);
 443 }
 444
 445 /* Compare addresses exactly.
 446  * v4-mapped-v6 is also in consideration.
 447  */
 448 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
 449                             const union sctp_addr *addr2)
 450 {
 451         if (addr1->sa.sa_family != addr2->sa.sa_family) {
 452                 if (addr1->sa.sa_family == AF_INET &&
 453                     addr2->sa.sa_family == AF_INET6 &&
 454                     IPV6_ADDR_MAPPED == ipv6_addr_type(&addr2->v6.sin6_addr)) {
 455                         if (addr2->v6.sin6_port == addr1->v4.sin_port &&
 456                             addr2->v6.sin6_addr.s6_addr32[3] ==
 457                             addr1->v4.sin_addr.s_addr)
 458                                 return 1;
 459                 }
 460                 if (addr2->sa.sa_family == AF_INET &&
 461                     addr1->sa.sa_family == AF_INET6 &&
 462                     IPV6_ADDR_MAPPED == ipv6_addr_type(&addr1->v6.sin6_addr)) {
 463                         if (addr1->v6.sin6_port == addr2->v4.sin_port &&
 464                             addr1->v6.sin6_addr.s6_addr32[3] ==
 465                             addr2->v4.sin_addr.s_addr)
 466                                 return 1;
 467                 }
 468                 return 0;
 469         }
 470         if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
 471                 return 0;
 472         /* If this is a linklocal address, compare the scope_id. */
 473         if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) {
 474                 if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
 475                     (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) {
 476                         return 0;
 477                 }
 478         }
 479
 480         return 1;
 481 }
 482
 483 /* Initialize addr struct to INADDR_ANY. */
 484 static void sctp_v6_inaddr_any(union sctp_addr *addr, unsigned short port)
 485 {
 486         memset(addr, 0x00, sizeof(union sctp_addr));
 487         addr->v6.sin6_family = AF_INET6;
 488         addr->v6.sin6_port = port;
 489 }
 490
 491 /* Is this a wildcard address? */
 492 static int sctp_v6_is_any(const union sctp_addr *addr)
 493 {
 494         return ipv6_addr_any(&addr->v6.sin6_addr);
 495 }
 496
 497 /* Should this be available for binding?   */
 498 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
 499 {
 500         int type;
 501         struct in6_addr *in6 = (struct in6_addr *)&addr->v6.sin6_addr;
 502
 503         type = ipv6_addr_type(in6);
 504         if (IPV6_ADDR_ANY == type)
 505                 return 1;
 506         if (type == IPV6_ADDR_MAPPED) {
 507                 if (sp && !sp->v4mapped)
 508                         return 0;
 509                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
 510                         return 0;
 511                 sctp_v6_map_v4(addr);
 512                 return sctp_get_af_specific(AF_INET)->available(addr, sp);
 513         }
 514         if (!(type & IPV6_ADDR_UNICAST))
 515                 return 0;
 516
 517         return ipv6_chk_addr(in6, NULL, 0);
 518 }
 519
 520 /* This function checks if the address is a valid address to be used for
 521  * SCTP.
 522  *
 523  * Output:
 524  * Return 0 - If the address is a non-unicast or an illegal address.
 525  * Return 1 - If the address is a unicast.
 526  */
 527 static int sctp_v6_addr_valid(union sctp_addr *addr,
 528                               struct sctp_sock *sp,
 529                               const struct sk_buff *skb)
 530 {
 531         int ret = ipv6_addr_type(&addr->v6.sin6_addr);
 532
 533         /* Support v4-mapped-v6 address. */
 534         if (ret == IPV6_ADDR_MAPPED) {
 535                 /* Note: This routine is used in input, so v4-mapped-v6
 536                  * are disallowed here when there is no sctp_sock.
 537                  */
 538                 if (!sp || !sp->v4mapped)
 539                         return 0;
 540                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
 541                         return 0;
 542                 sctp_v6_map_v4(addr);
 543                 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb);
 544         }
 545
 546         /* Is this a non-unicast address */
 547         if (!(ret & IPV6_ADDR_UNICAST))
 548                 return 0;
 549
 550         return 1;
 551 }
 552
 553 /* What is the scope of 'addr'?  */
 554 static sctp_scope_t sctp_v6_scope(union sctp_addr *addr)
 555 {
 556         int v6scope;
 557         sctp_scope_t retval;
 558
 559         /* The IPv6 scope is really a set of bit fields.
 560          * See IFA_* in <net/if_inet6.h>.  Map to a generic SCTP scope.
 561          */
 562
 563         v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
 564         switch (v6scope) {
 565         case IFA_HOST:
 566                 retval = SCTP_SCOPE_LOOPBACK;
 567                 break;
 568         case IFA_LINK:
 569                 retval = SCTP_SCOPE_LINK;
 570                 break;
 571         case IFA_SITE:
 572                 retval = SCTP_SCOPE_PRIVATE;
 573                 break;
 574         default:
 575                 retval = SCTP_SCOPE_GLOBAL;
 576                 break;
 577         };
 578
 579         return retval;
 580 }
 581
 582 /* Create and initialize a new sk for the socket to be returned by accept(). */
 583 static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
 584                                              struct sctp_association *asoc)
 585 {
 586         struct inet_sock *inet = inet_sk(sk);
 587         struct sock *newsk;
 588         struct inet_sock *newinet;
 589         struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
 590         struct sctp6_sock *newsctp6sk;
 591
 592         newsk = sk_alloc(PF_INET6, GFP_KERNEL, sk->sk_prot, 1);
 593         if (!newsk)
 594                 goto out;
 595
 596         sock_init_data(NULL, newsk);
 597
 598         newsk->sk_type = SOCK_STREAM;
 599
 600         newsk->sk_prot = sk->sk_prot;
 601         newsk->sk_no_check = sk->sk_no_check;
 602         newsk->sk_reuse = sk->sk_reuse;
 603
 604         newsk->sk_destruct = inet_sock_destruct;
 605         newsk->sk_family = PF_INET6;
 606         newsk->sk_protocol = IPPROTO_SCTP;
 607         newsk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
 608         newsk->sk_shutdown = sk->sk_shutdown;
 609         sock_reset_flag(sk, SOCK_ZAPPED);
 610
 611         newsctp6sk = (struct sctp6_sock *)newsk;
 612         inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
 613
 614         newinet = inet_sk(newsk);
 615         newnp = inet6_sk(newsk);
 616
 617         memcpy(newnp, np, sizeof(struct ipv6_pinfo));
 618
 619         /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
 620          * and getpeername().
 621          */
 622         newinet->sport = inet->sport;
 623         newnp->saddr = np->saddr;
 624         newnp->rcv_saddr = np->rcv_saddr;
 625         newinet->dport = htons(asoc->peer.port);
 626         sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
 627
 628         /* Init the ipv4 part of the socket since we can have sockets
 629          * using v6 API for ipv4.
 630          */
 631         newinet->uc_ttl = -1;
 632         newinet->mc_loop = 1;
 633         newinet->mc_ttl = 1;
 634         newinet->mc_index = 0;
 635         newinet->mc_list = NULL;
 636
 637         if (ipv4_config.no_pmtu_disc)
 638                 newinet->pmtudisc = IP_PMTUDISC_DONT;
 639         else
 640                 newinet->pmtudisc = IP_PMTUDISC_WANT;
 641
 642         sk_refcnt_debug_inc(newsk);
 643
 644         if (newsk->sk_prot->init(newsk)) {
 645                 sk_common_release(newsk);
 646                 newsk = NULL;
 647         }
 648
 649 out:
 650         return newsk;
 651 }
 652
 653 /* Map v4 address to mapped v6 address */
 654 static void sctp_v6_addr_v4map(struct sctp_sock *sp, union sctp_addr *addr)
 655 {
 656         if (sp->v4mapped && AF_INET == addr->sa.sa_family)
 657                 sctp_v4_map_v6(addr);
 658 }
 659
 660 /* Where did this skb come from?  */
 661 static int sctp_v6_skb_iif(const struct sk_buff *skb)
 662 {
 663         struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb;
 664         return opt->iif;
 665 }
 666
 667 /* Was this packet marked by Explicit Congestion Notification? */
 668 static int sctp_v6_is_ce(const struct sk_buff *skb)
 669 {
 670         return *((__u32 *)(skb->nh.ipv6h)) & htonl(1<<20);
 671 }
 672
 673 /* Dump the v6 addr to the seq file. */
 674 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
 675 {
 676         seq_printf(seq, NIP6_FMT " ", NIP6(addr->v6.sin6_addr));
 677 }
 678
 679 /* Initialize a PF_INET6 socket msg_name. */
 680 static void sctp_inet6_msgname(char *msgname, int *addr_len)
 681 {
 682         struct sockaddr_in6 *sin6;
 683
 684         sin6 = (struct sockaddr_in6 *)msgname;
 685         sin6->sin6_family = AF_INET6;
 686         sin6->sin6_flowinfo = 0;
 687         sin6->sin6_scope_id = 0; /*FIXME */
 688         *addr_len = sizeof(struct sockaddr_in6);
 689 }
 690
 691 /* Initialize a PF_INET msgname from a ulpevent. */
 692 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
 693                                      char *msgname, int *addrlen)
 694 {
 695         struct sockaddr_in6 *sin6, *sin6from;
 696
 697         if (msgname) {
 698                 union sctp_addr *addr;
 699                 struct sctp_association *asoc;
 700
 701                 asoc = event->asoc;
 702                 sctp_inet6_msgname(msgname, addrlen);
 703                 sin6 = (struct sockaddr_in6 *)msgname;
 704                 sin6->sin6_port = htons(asoc->peer.port);
 705                 addr = &asoc->peer.primary_addr;
 706
 707                 /* Note: If we go to a common v6 format, this code
 708                  * will change.
 709                  */
 710
 711                 /* Map ipv4 address into v4-mapped-on-v6 address.  */
 712                 if (sctp_sk(asoc->base.sk)->v4mapped &&
 713                     AF_INET == addr->sa.sa_family) {
 714                         sctp_v4_map_v6((union sctp_addr *)sin6);
 715                         sin6->sin6_addr.s6_addr32[3] =
 716                                 addr->v4.sin_addr.s_addr;
 717                         return;
 718                 }
 719
 720                 sin6from = &asoc->peer.primary_addr.v6;
 721                 ipv6_addr_copy(&sin6->sin6_addr, &sin6from->sin6_addr);
 722                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 723                         sin6->sin6_scope_id = sin6from->sin6_scope_id;
 724         }
 725 }
 726
 727 /* Initialize a msg_name from an inbound skb. */
 728 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
 729                                    int *addr_len)
 730 {
 731         struct sctphdr *sh;
 732         struct sockaddr_in6 *sin6;
 733
 734         if (msgname) {
 735                 sctp_inet6_msgname(msgname, addr_len);
 736                 sin6 = (struct sockaddr_in6 *)msgname;
 737                 sh = (struct sctphdr *)skb->h.raw;
 738                 sin6->sin6_port = sh->source;
 739
 740                 /* Map ipv4 address into v4-mapped-on-v6 address. */
 741                 if (sctp_sk(skb->sk)->v4mapped &&
 742                     skb->nh.iph->version == 4) {
 743                         sctp_v4_map_v6((union sctp_addr *)sin6);
 744                         sin6->sin6_addr.s6_addr32[3] = skb->nh.iph->saddr;
 745                         return;
 746                 }
 747
 748                 /* Otherwise, just copy the v6 address. */
 749                 ipv6_addr_copy(&sin6->sin6_addr, &skb->nh.ipv6h->saddr);
 750                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) {
 751                         struct sctp_ulpevent *ev = sctp_skb2event(skb);
 752                         sin6->sin6_scope_id = ev->iif;
 753                 }
 754         }
 755 }
 756
 757 /* Do we support this AF? */
 758 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
 759 {
 760         switch (family) {
 761         case AF_INET6:
 762                 return 1;
 763         /* v4-mapped-v6 addresses */
 764         case AF_INET:
 765                 if (!__ipv6_only_sock(sctp_opt2sk(sp)) && sp->v4mapped)
 766                         return 1;
 767         default:
 768                 return 0;
 769         }
 770 }
 771
 772 /* Address matching with wildcards allowed.  This extra level
 773  * of indirection lets us choose whether a PF_INET6 should
 774  * disallow any v4 addresses if we so choose.
 775  */
 776 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
 777                                const union sctp_addr *addr2,
 778                                struct sctp_sock *opt)
 779 {
 780         struct sctp_af *af1, *af2;
 781
 782         af1 = sctp_get_af_specific(addr1->sa.sa_family);
 783         af2 = sctp_get_af_specific(addr2->sa.sa_family);
 784
 785         if (!af1 || !af2)
 786                 return 0;
 787         /* Today, wildcard AF_INET/AF_INET6. */
 788         if (sctp_is_any(addr1) || sctp_is_any(addr2))
 789                 return 1;
 790
 791         if (addr1->sa.sa_family != addr2->sa.sa_family)
 792                 return 0;
 793
 794         return af1->cmp_addr(addr1, addr2);
 795 }
 796
 797 /* Verify that the provided sockaddr looks bindable.   Common verification,
 798  * has already been taken care of.
 799  */
 800 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
 801 {
 802         struct sctp_af *af;
 803
 804         /* ASSERT: address family has already been verified. */
 805         if (addr->sa.sa_family != AF_INET6)
 806                 af = sctp_get_af_specific(addr->sa.sa_family);
 807         else {
 808                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
 809                 struct net_device *dev;
 810
 811                 if (type & IPV6_ADDR_LINKLOCAL) {
 812                         if (!addr->v6.sin6_scope_id)
 813                                 return 0;
 814                         dev = dev_get_by_index(addr->v6.sin6_scope_id);
 815                         if (!dev)
 816                                 return 0;
 817                         dev_put(dev);
 818                 }
 819                 af = opt->pf->af;
 820         }
 821         return af->available(addr, opt);
 822 }
 823
 824 /* Verify that the provided sockaddr looks sendable.   Common verification,
 825  * has already been taken care of.
 826  */
 827 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
 828 {
 829         struct sctp_af *af = NULL;
 830
 831         /* ASSERT: address family has already been verified. */
 832         if (addr->sa.sa_family != AF_INET6)
 833                 af = sctp_get_af_specific(addr->sa.sa_family);
 834         else {
 835                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
 836                 struct net_device *dev;
 837
 838                 if (type & IPV6_ADDR_LINKLOCAL) {
 839                         if (!addr->v6.sin6_scope_id)
 840                                 return 0;
 841                         dev = dev_get_by_index(addr->v6.sin6_scope_id);
 842                         if (!dev)
 843                                 return 0;
 844                         dev_put(dev);
 845                 }
 846                 af = opt->pf->af;
 847         }
 848
 849         return af != NULL;
 850 }
 851
 852 /* Fill in Supported Address Type information for INIT and INIT-ACK
 853  * chunks.   Note: In the future, we may want to look at sock options
 854  * to determine whether a PF_INET6 socket really wants to have IPV4
 855  * addresses.
 856  * Returns number of addresses supported.
 857  */
 858 static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
 859                                       __u16 *types)
 860 {
 861         types[0] = SCTP_PARAM_IPV4_ADDRESS;
 862         types[1] = SCTP_PARAM_IPV6_ADDRESS;
 863         return 2;
 864 }
 865
 866 static const struct proto_ops inet6_seqpacket_ops = {
 867         .family            = PF_INET6,
 868         .owner             = THIS_MODULE,
 869         .release           = inet6_release,
 870         .bind              = inet6_bind,
 871         .connect           = inet_dgram_connect,
 872         .socketpair        = sock_no_socketpair,
 873         .accept            = inet_accept,
 874         .getname           = inet6_getname,
 875         .poll              = sctp_poll,
 876         .ioctl             = inet6_ioctl,
 877         .listen            = sctp_inet_listen,
 878         .shutdown          = inet_shutdown,
 879         .setsockopt        = sock_common_setsockopt,
 880         .getsockopt        = sock_common_getsockopt,
 881         .sendmsg           = inet_sendmsg,
 882         .recvmsg           = sock_common_recvmsg,
 883         .mmap              = sock_no_mmap,
 884 #ifdef CONFIG_COMPAT
 885         .compat_setsockopt = compat_sock_common_setsockopt,
 886         .compat_getsockopt = compat_sock_common_getsockopt,
 887 #endif
 888 };
 889
 890 static struct inet_protosw sctpv6_seqpacket_protosw = {
 891         .type          = SOCK_SEQPACKET,
 892         .protocol      = IPPROTO_SCTP,
 893         .prot          = &sctpv6_prot,
 894         .ops           = &inet6_seqpacket_ops,
 895         .capability    = -1,
 896         .no_check      = 0,
 897         .flags         = SCTP_PROTOSW_FLAG
 898 };
 899 static struct inet_protosw sctpv6_stream_protosw = {
 900         .type          = SOCK_STREAM,
 901         .protocol      = IPPROTO_SCTP,
 902         .prot          = &sctpv6_prot,
 903         .ops           = &inet6_seqpacket_ops,
 904         .capability    = -1,
 905         .no_check      = 0,
 906         .flags         = SCTP_PROTOSW_FLAG,
 907 };
 908
 909 static int sctp6_rcv(struct sk_buff **pskb)
 910 {
 911         return sctp_rcv(*pskb) ? -1 : 0;
 912 }
 913
 914 static struct inet6_protocol sctpv6_protocol = {
 915         .handler      = sctp6_rcv,
 916         .err_handler  = sctp_v6_err,
 917         .flags        = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
 918 };
 919
 920 static struct sctp_af sctp_ipv6_specific = {
 921         .sa_family         = AF_INET6,
 922         .sctp_xmit         = sctp_v6_xmit,
 923         .setsockopt        = ipv6_setsockopt,
 924         .getsockopt        = ipv6_getsockopt,
 925         .get_dst           = sctp_v6_get_dst,
 926         .get_saddr         = sctp_v6_get_saddr,
 927         .copy_addrlist     = sctp_v6_copy_addrlist,
 928         .from_skb          = sctp_v6_from_skb,
 929         .from_sk           = sctp_v6_from_sk,
 930         .to_sk_saddr       = sctp_v6_to_sk_saddr,
 931         .to_sk_daddr       = sctp_v6_to_sk_daddr,
 932         .from_addr_param   = sctp_v6_from_addr_param,
 933         .to_addr_param     = sctp_v6_to_addr_param,
 934         .dst_saddr         = sctp_v6_dst_saddr,
 935         .cmp_addr          = sctp_v6_cmp_addr,
 936         .scope             = sctp_v6_scope,
 937         .addr_valid        = sctp_v6_addr_valid,
 938         .inaddr_any        = sctp_v6_inaddr_any,
 939         .is_any            = sctp_v6_is_any,
 940         .available         = sctp_v6_available,
 941         .skb_iif           = sctp_v6_skb_iif,
 942         .is_ce             = sctp_v6_is_ce,
 943         .seq_dump_addr     = sctp_v6_seq_dump_addr,
 944         .net_header_len    = sizeof(struct ipv6hdr),
 945         .sockaddr_len      = sizeof(struct sockaddr_in6),
 946 #ifdef CONFIG_COMPAT
 947         .compat_setsockopt = compat_ipv6_setsockopt,
 948         .compat_getsockopt = compat_ipv6_getsockopt,
 949 #endif
 950 };
 951
 952 static struct sctp_pf sctp_pf_inet6_specific = {
 953         .event_msgname = sctp_inet6_event_msgname,
 954         .skb_msgname   = sctp_inet6_skb_msgname,
 955         .af_supported  = sctp_inet6_af_supported,
 956         .cmp_addr      = sctp_inet6_cmp_addr,
 957         .bind_verify   = sctp_inet6_bind_verify,
 958         .send_verify   = sctp_inet6_send_verify,
 959         .supported_addrs = sctp_inet6_supported_addrs,
 960         .create_accept_sk = sctp_v6_create_accept_sk,
 961         .addr_v4map    = sctp_v6_addr_v4map,
 962         .af            = &sctp_ipv6_specific,
 963 };
 964
 965 /* Initialize IPv6 support and register with inet6 stack.  */
 966 int sctp_v6_init(void)
 967 {
 968         int rc = proto_register(&sctpv6_prot, 1);
 969
 970         if (rc)
 971                 goto out;
 972         /* Register inet6 protocol. */
 973         rc = -EAGAIN;
 974         if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
 975                 goto out_unregister_sctp_proto;
 976
 977         /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
 978         inet6_register_protosw(&sctpv6_seqpacket_protosw);
 979         inet6_register_protosw(&sctpv6_stream_protosw);
 980
 981         /* Register the SCTP specific PF_INET6 functions. */
 982         sctp_register_pf(&sctp_pf_inet6_specific, PF_INET6);
 983
 984         /* Register the SCTP specific AF_INET6 functions. */
 985         sctp_register_af(&sctp_ipv6_specific);
 986
 987         /* Register notifier for inet6 address additions/deletions. */
 988         register_inet6addr_notifier(&sctp_inet6addr_notifier);
 989         rc = 0;
 990 out:
 991         return rc;
 992 out_unregister_sctp_proto:
 993         proto_unregister(&sctpv6_prot);
 994         goto out;
 995 }
 996
 997 /* IPv6 specific exit support. */
 998 void sctp_v6_exit(void)
 999 {
1000         list_del(&sctp_ipv6_specific.list);
1001         inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
1002         inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
1003         inet6_unregister_protosw(&sctpv6_stream_protosw);
1004         unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1005         proto_unregister(&sctpv6_prot);
1006 }