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/tcp.h>
  70 #include <net/ndisc.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 struct notifier_block sctp_inetaddr_notifier;
  82
  83 /* ICMP error handler. */
  84 void sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
  85                  int type, int code, int offset, __u32 info)
  86 {
  87         struct inet6_dev *idev;
  88         struct ipv6hdr *iph = (struct ipv6hdr *)skb->data;
  89         struct sctphdr *sh = (struct sctphdr *)(skb->data + offset);
  90         struct sock *sk;
  91         struct sctp_endpoint *ep;
  92         struct sctp_association *asoc;
  93         struct sctp_transport *transport;
  94         struct ipv6_pinfo *np;
  95         char *saveip, *savesctp;
  96         int err;
  97
  98         idev = in6_dev_get(skb->dev);
  99
 100         /* Fix up skb to look at the embedded net header. */
 101         saveip = skb->nh.raw;
 102         savesctp  = skb->h.raw;
 103         skb->nh.ipv6h = iph;
 104         skb->h.raw = (char *)sh;
 105         sk = sctp_err_lookup(AF_INET6, skb, sh, &ep, &asoc, &transport);
 106         /* Put back, the original pointers. */
 107         skb->nh.raw = saveip;
 108         skb->h.raw = savesctp;
 109         if (!sk) {
 110                 ICMP6_INC_STATS_BH(idev, Icmp6InErrors);
 111                 goto out;
 112         }
 113
 114         /* Warning:  The sock lock is held.  Remember to call
 115          * sctp_err_finish!
 116          */
 117
 118         switch (type) {
 119         case ICMPV6_PKT_TOOBIG:
 120                 sctp_icmp_frag_needed(sk, asoc, transport, ntohl(info));
 121                 goto out_unlock;
 122         default:
 123                 break;
 124         }
 125
 126         np = inet6_sk(sk);
 127         icmpv6_err_convert(type, code, &err);
 128         if (!sock_owned_by_user(sk) && np->recverr) {
 129                 sk->sk_err = err;
 130                 sk->sk_error_report(sk);
 131         } else {  /* Only an error on timeout */
 132                 sk->sk_err_soft = err;
 133         }
 134
 135 out_unlock:
 136         sctp_err_finish(sk, ep, asoc);
 137 out:
 138         if (likely(idev != NULL))
 139                 in6_dev_put(idev);
 140 }
 141
 142 /* Based on tcp_v6_xmit() in tcp_ipv6.c. */
 143 static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *transport,
 144                         int ipfragok)
 145 {
 146         struct sock *sk = skb->sk;
 147         struct ipv6_pinfo *np = inet6_sk(sk);
 148         struct flowi fl;
 149
 150         memset(&fl, 0, sizeof(fl));
 151
 152         fl.proto = sk->sk_protocol;
 153
 154         /* Fill in the dest address from the route entry passed with the skb
 155          * and the source address from the transport.
 156          */
 157         ipv6_addr_copy(&fl.fl6_dst, &transport->ipaddr.v6.sin6_addr);
 158         ipv6_addr_copy(&fl.fl6_src, &transport->saddr.v6.sin6_addr);
 159
 160         fl.fl6_flowlabel = np->flow_label;
 161         IP6_ECN_flow_xmit(sk, fl.fl6_flowlabel);
 162         if (ipv6_addr_type(&fl.fl6_src) & IPV6_ADDR_LINKLOCAL)
 163                 fl.oif = transport->saddr.v6.sin6_scope_id;
 164         else
 165                 fl.oif = sk->sk_bound_dev_if;
 166         fl.fl_ip_sport = inet_sk(sk)->sport;
 167         fl.fl_ip_dport = transport->ipaddr.v6.sin6_port;
 168
 169         if (np->opt && np->opt->srcrt) {
 170                 struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
 171                 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
 172         }
 173
 174         SCTP_DEBUG_PRINTK("%s: skb:%p, len:%d, "
 175                           "src:%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x "
 176                           "dst:%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
 177                           __FUNCTION__, skb, skb->len,
 178                           NIP6(fl.fl6_src), NIP6(fl.fl6_dst));
 179
 180         SCTP_INC_STATS(SctpOutSCTPPacks);
 181
 182         return ip6_xmit(sk, skb, &fl, np->opt, ipfragok);
 183 }
 184
 185 /* Returns the dst cache entry for the given source and destination ip
 186  * addresses.
 187  */
 188 struct dst_entry *sctp_v6_get_dst(struct sctp_association *asoc,
 189                                   union sctp_addr *daddr,
 190                                   union sctp_addr *saddr)
 191 {
 192         struct dst_entry *dst;
 193         struct flowi fl;
 194
 195         memset(&fl, 0, sizeof(fl));
 196         ipv6_addr_copy(&fl.fl6_dst, &daddr->v6.sin6_addr);
 197         if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
 198                 fl.oif = daddr->v6.sin6_scope_id;
 199
 200
 201         SCTP_DEBUG_PRINTK("%s: DST=%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x ",
 202                           __FUNCTION__, NIP6(fl.fl6_dst));
 203
 204         if (saddr) {
 205                 ipv6_addr_copy(&fl.fl6_src, &saddr->v6.sin6_addr);
 206                 SCTP_DEBUG_PRINTK(
 207                         "SRC=%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x - ",
 208                         NIP6(fl.fl6_src));
 209         }
 210
 211         dst = ip6_route_output(NULL, &fl);
 212         if (dst) {
 213                 struct rt6_info *rt;
 214                 rt = (struct rt6_info *)dst;
 215                 SCTP_DEBUG_PRINTK(
 216                         "rt6_dst:%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x "
 217                         "rt6_src:%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
 218                         NIP6(rt->rt6i_dst.addr), NIP6(rt->rt6i_src.addr));
 219         } else {
 220                 SCTP_DEBUG_PRINTK("NO ROUTE\n");
 221         }
 222
 223         return dst;
 224 }
 225
 226 /* Returns the number of consecutive initial bits that match in the 2 ipv6
 227  * addresses.
 228  */
 229 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
 230                                          union sctp_addr *s2)
 231 {
 232         struct in6_addr *a1 = &s1->v6.sin6_addr;
 233         struct in6_addr *a2 = &s2->v6.sin6_addr;
 234         int i, j;
 235
 236         for (i = 0; i < 4 ; i++) {
 237                 __u32 a1xora2;
 238
 239                 a1xora2 = a1->s6_addr32[i] ^ a2->s6_addr32[i];
 240
 241                 if ((j = fls(ntohl(a1xora2))))
 242                         return (i * 32 + 32 - j);
 243         }
 244
 245         return (i*32);
 246 }
 247
 248 /* Fills in the source address(saddr) based on the destination address(daddr)
 249  * and asoc's bind address list.
 250  */
 251 void sctp_v6_get_saddr(struct sctp_association *asoc, struct dst_entry *dst,
 252                        union sctp_addr *daddr, union sctp_addr *saddr)
 253 {
 254         struct sctp_bind_addr *bp;
 255         rwlock_t *addr_lock;
 256         struct sctp_sockaddr_entry *laddr;
 257         struct list_head *pos;
 258         sctp_scope_t scope;
 259         union sctp_addr *baddr = NULL;
 260         __u8 matchlen = 0;
 261         __u8 bmatchlen;
 262
 263         SCTP_DEBUG_PRINTK("%s: asoc:%p dst:%p "
 264                           "daddr:%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x ",
 265                           __FUNCTION__, asoc, dst, NIP6(daddr->v6.sin6_addr));
 266
 267         if (!asoc) {
 268                 ipv6_get_saddr(dst, &daddr->v6.sin6_addr,&saddr->v6.sin6_addr);
 269                 SCTP_DEBUG_PRINTK("saddr from ipv6_get_saddr: "
 270                                   "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
 271                                   NIP6(saddr->v6.sin6_addr));
 272                 return;
 273         }
 274
 275         scope = sctp_scope(daddr);
 276
 277         bp = &asoc->base.bind_addr;
 278         addr_lock = &asoc->base.addr_lock;
 279
 280         /* Go through the bind address list and find the best source address
 281          * that matches the scope of the destination address.
 282          */
 283         sctp_read_lock(addr_lock);
 284         list_for_each(pos, &bp->address_list) {
 285                 laddr = list_entry(pos, struct sctp_sockaddr_entry, list);
 286                 if ((laddr->a.sa.sa_family == AF_INET6) &&
 287                     (scope <= sctp_scope(&laddr->a))) {
 288                         bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
 289                         if (!baddr || (matchlen < bmatchlen)) {
 290                                 baddr = &laddr->a;
 291                                 matchlen = bmatchlen;
 292                         }
 293                 }
 294         }
 295
 296         if (baddr) {
 297                 memcpy(saddr, baddr, sizeof(union sctp_addr));
 298                 SCTP_DEBUG_PRINTK("saddr: "
 299                                   "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
 300                                   NIP6(saddr->v6.sin6_addr));
 301         } else {
 302                 printk(KERN_ERR "%s: asoc:%p Could not find a valid source "
 303                        "address for the "
 304                        "dest:%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
 305                        __FUNCTION__, asoc, NIP6(daddr->v6.sin6_addr));
 306         }
 307
 308         sctp_read_unlock(addr_lock);
 309 }
 310
 311 /* Make a copy of all potential local addresses. */
 312 static void sctp_v6_copy_addrlist(struct list_head *addrlist,
 313                                   struct net_device *dev)
 314 {
 315         struct inet6_dev *in6_dev;
 316         struct inet6_ifaddr *ifp;
 317         struct sctp_sockaddr_entry *addr;
 318
 319         read_lock(&addrconf_lock);
 320         if ((in6_dev = __in6_dev_get(dev)) == NULL) {
 321                 read_unlock(&addrconf_lock);
 322                 return;
 323         }
 324
 325         read_lock(&in6_dev->lock);
 326         for (ifp = in6_dev->addr_list; ifp; ifp = ifp->if_next) {
 327                 /* Add the address to the local list.  */
 328                 addr = t_new(struct sctp_sockaddr_entry, GFP_ATOMIC);
 329                 if (addr) {
 330                         addr->a.v6.sin6_family = AF_INET6;
 331                         addr->a.v6.sin6_port = 0;
 332                         addr->a.v6.sin6_addr = ifp->addr;
 333                         addr->a.v6.sin6_scope_id = dev->ifindex;
 334                         INIT_LIST_HEAD(&addr->list);
 335                         list_add_tail(&addr->list, addrlist);
 336                 }
 337         }
 338
 339         read_unlock(&in6_dev->lock);
 340         read_unlock(&addrconf_lock);
 341 }
 342
 343 /* Initialize a sockaddr_storage from in incoming skb. */
 344 static void sctp_v6_from_skb(union sctp_addr *addr,struct sk_buff *skb,
 345                              int is_saddr)
 346 {
 347         void *from;
 348         __u16 *port;
 349         struct sctphdr *sh;
 350
 351         port = &addr->v6.sin6_port;
 352         addr->v6.sin6_family = AF_INET6;
 353         addr->v6.sin6_flowinfo = 0; /* FIXME */
 354         addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif;
 355
 356         sh = (struct sctphdr *) skb->h.raw;
 357         if (is_saddr) {
 358                 *port  = ntohs(sh->source);
 359                 from = &skb->nh.ipv6h->saddr;
 360         } else {
 361                 *port = ntohs(sh->dest);
 362                 from = &skb->nh.ipv6h->daddr;
 363         }
 364         ipv6_addr_copy(&addr->v6.sin6_addr, from);
 365 }
 366
 367 /* Initialize an sctp_addr from a socket. */
 368 static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
 369 {
 370         addr->v6.sin6_family = AF_INET6;
 371         addr->v6.sin6_port = inet_sk(sk)->num;
 372         addr->v6.sin6_addr = inet6_sk(sk)->rcv_saddr;
 373 }
 374
 375 /* Initialize sk->sk_rcv_saddr from sctp_addr. */
 376 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
 377 {
 378         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
 379                 inet6_sk(sk)->rcv_saddr.s6_addr32[0] = 0;
 380                 inet6_sk(sk)->rcv_saddr.s6_addr32[1] = 0;
 381                 inet6_sk(sk)->rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
 382                 inet6_sk(sk)->rcv_saddr.s6_addr32[3] =
 383                         addr->v4.sin_addr.s_addr;
 384         } else {
 385                 inet6_sk(sk)->rcv_saddr = addr->v6.sin6_addr;
 386         }
 387 }
 388
 389 /* Initialize sk->sk_daddr from sctp_addr. */
 390 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
 391 {
 392         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
 393                 inet6_sk(sk)->daddr.s6_addr32[0] = 0;
 394                 inet6_sk(sk)->daddr.s6_addr32[1] = 0;
 395                 inet6_sk(sk)->daddr.s6_addr32[2] = htonl(0x0000ffff);
 396                 inet6_sk(sk)->daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
 397         } else {
 398                 inet6_sk(sk)->daddr = addr->v6.sin6_addr;
 399         }
 400 }
 401
 402 /* Initialize a sctp_addr from an address parameter. */
 403 static void sctp_v6_from_addr_param(union sctp_addr *addr,
 404                                     union sctp_addr_param *param,
 405                                     __u16 port, int iif)
 406 {
 407         addr->v6.sin6_family = AF_INET6;
 408         addr->v6.sin6_port = port;
 409         addr->v6.sin6_flowinfo = 0; /* BUG */
 410         ipv6_addr_copy(&addr->v6.sin6_addr, &param->v6.addr);
 411         addr->v6.sin6_scope_id = iif;
 412 }
 413
 414 /* Initialize an address parameter from a sctp_addr and return the length
 415  * of the address parameter.
 416  */
 417 static int sctp_v6_to_addr_param(const union sctp_addr *addr,
 418                                  union sctp_addr_param *param)
 419 {
 420         int length = sizeof(sctp_ipv6addr_param_t);
 421
 422         param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
 423         param->v6.param_hdr.length = ntohs(length);
 424         ipv6_addr_copy(&param->v6.addr, &addr->v6.sin6_addr);
 425
 426         return length;
 427 }
 428
 429 /* Initialize a sctp_addr from a dst_entry. */
 430 static void sctp_v6_dst_saddr(union sctp_addr *addr, struct dst_entry *dst,
 431                               unsigned short port)
 432 {
 433         struct rt6_info *rt = (struct rt6_info *)dst;
 434         addr->sa.sa_family = AF_INET6;
 435         addr->v6.sin6_port = port;
 436         ipv6_addr_copy(&addr->v6.sin6_addr, &rt->rt6i_src.addr);
 437 }
 438
 439 /* Compare addresses exactly.
 440  * v4-mapped-v6 is also in consideration.
 441  */
 442 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
 443                             const union sctp_addr *addr2)
 444 {
 445         if (addr1->sa.sa_family != addr2->sa.sa_family) {
 446                 if (addr1->sa.sa_family == AF_INET &&
 447                     addr2->sa.sa_family == AF_INET6 &&
 448                     IPV6_ADDR_MAPPED == ipv6_addr_type(&addr2->v6.sin6_addr)) {
 449                         if (addr2->v6.sin6_port == addr1->v4.sin_port &&
 450                             addr2->v6.sin6_addr.s6_addr32[3] ==
 451                             addr1->v4.sin_addr.s_addr)
 452                                 return 1;
 453                 }
 454                 if (addr2->sa.sa_family == AF_INET &&
 455                     addr1->sa.sa_family == AF_INET6 &&
 456                     IPV6_ADDR_MAPPED == ipv6_addr_type(&addr1->v6.sin6_addr)) {
 457                         if (addr1->v6.sin6_port == addr2->v4.sin_port &&
 458                             addr1->v6.sin6_addr.s6_addr32[3] ==
 459                             addr2->v4.sin_addr.s_addr)
 460                                 return 1;
 461                 }
 462                 return 0;
 463         }
 464         if (ipv6_addr_cmp(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
 465                 return 0;
 466         /* If this is a linklocal address, compare the scope_id. */
 467         if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) {
 468                 if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
 469                     (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) {
 470                         return 0;
 471                 }
 472         }
 473
 474         return 1;
 475 }
 476
 477 /* Initialize addr struct to INADDR_ANY. */
 478 static void sctp_v6_inaddr_any(union sctp_addr *addr, unsigned short port)
 479 {
 480         memset(addr, 0x00, sizeof(union sctp_addr));
 481         addr->v6.sin6_family = AF_INET6;
 482         addr->v6.sin6_port = port;
 483 }
 484
 485 /* Is this a wildcard address? */
 486 static int sctp_v6_is_any(const union sctp_addr *addr)
 487 {
 488         int type;
 489         type = ipv6_addr_type((struct in6_addr *)&addr->v6.sin6_addr);
 490         return IPV6_ADDR_ANY == type;
 491 }
 492
 493 /* Should this be available for binding?   */
 494 static int sctp_v6_available(union sctp_addr *addr, struct sctp_opt *sp)
 495 {
 496         int type;
 497         struct in6_addr *in6 = (struct in6_addr *)&addr->v6.sin6_addr;
 498
 499         type = ipv6_addr_type(in6);
 500         if (IPV6_ADDR_ANY == type)
 501                 return 1;
 502         if (type == IPV6_ADDR_MAPPED) {
 503                 if (sp && !sp->v4mapped)
 504                         return 0;
 505                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
 506                         return 0;
 507                 sctp_v6_map_v4(addr);
 508                 return sctp_get_af_specific(AF_INET)->available(addr, sp);
 509         }
 510         if (!(type & IPV6_ADDR_UNICAST))
 511                 return 0;
 512
 513         return ipv6_chk_addr(in6, NULL, 0);
 514 }
 515
 516 /* This function checks if the address is a valid address to be used for
 517  * SCTP.
 518  *
 519  * Output:
 520  * Return 0 - If the address is a non-unicast or an illegal address.
 521  * Return 1 - If the address is a unicast.
 522  */
 523 static int sctp_v6_addr_valid(union sctp_addr *addr, struct sctp_opt *sp)
 524 {
 525         int ret = ipv6_addr_type(&addr->v6.sin6_addr);
 526
 527         /* Support v4-mapped-v6 address. */
 528         if (ret == IPV6_ADDR_MAPPED) {
 529                 /* Note: This routine is used in input, so v4-mapped-v6
 530                  * are disallowed here when there is no sctp_opt.
 531                  */
 532                 if (!sp || !sp->v4mapped)
 533                         return 0;
 534                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
 535                         return 0;
 536                 sctp_v6_map_v4(addr);
 537                 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp);
 538         }
 539
 540         /* Is this a non-unicast address */
 541         if (!(ret & IPV6_ADDR_UNICAST))
 542                 return 0;
 543
 544         return 1;
 545 }
 546
 547 /* What is the scope of 'addr'?  */
 548 static sctp_scope_t sctp_v6_scope(union sctp_addr *addr)
 549 {
 550         int v6scope;
 551         sctp_scope_t retval;
 552
 553         /* The IPv6 scope is really a set of bit fields.
 554          * See IFA_* in <net/if_inet6.h>.  Map to a generic SCTP scope.
 555          */
 556
 557         v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
 558         switch (v6scope) {
 559         case IFA_HOST:
 560                 retval = SCTP_SCOPE_LOOPBACK;
 561                 break;
 562         case IFA_LINK:
 563                 retval = SCTP_SCOPE_LINK;
 564                 break;
 565         case IFA_SITE:
 566                 retval = SCTP_SCOPE_PRIVATE;
 567                 break;
 568         default:
 569                 retval = SCTP_SCOPE_GLOBAL;
 570                 break;
 571         };
 572
 573         return retval;
 574 }
 575
 576 /* Create and initialize a new sk for the socket to be returned by accept(). */
 577 struct sock *sctp_v6_create_accept_sk(struct sock *sk,
 578                                       struct sctp_association *asoc)
 579 {
 580         struct inet_opt *inet = inet_sk(sk);
 581         struct sock *newsk;
 582         struct inet_opt *newinet;
 583         struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
 584         struct sctp6_sock *newsctp6sk;
 585
 586         newsk = sk_alloc(PF_INET6, GFP_KERNEL, sizeof(struct sctp6_sock),
 587                          sk->sk_slab);
 588         if (!newsk)
 589                 goto out;
 590
 591         sock_init_data(NULL, newsk);
 592         sk_set_owner(newsk, THIS_MODULE);
 593
 594         newsk->sk_type = SOCK_STREAM;
 595
 596         newsk->sk_prot = sk->sk_prot;
 597         newsk->sk_no_check = sk->sk_no_check;
 598         newsk->sk_reuse = sk->sk_reuse;
 599
 600         newsk->sk_destruct = inet_sock_destruct;
 601         newsk->sk_zapped = 0;
 602         newsk->sk_family = PF_INET6;
 603         newsk->sk_protocol = IPPROTO_SCTP;
 604         newsk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
 605         newsk->sk_shutdown = sk->sk_shutdown;
 606
 607         newsctp6sk = (struct sctp6_sock *)newsk;
 608         newsctp6sk->pinet6 = &newsctp6sk->inet6;
 609
 610         newinet = inet_sk(newsk);
 611         newnp = inet6_sk(newsk);
 612
 613         memcpy(newnp, np, sizeof(struct ipv6_pinfo));
 614
 615         /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
 616          * and getpeername().
 617          */
 618         newinet->sport = inet->sport;
 619         newnp->saddr = np->saddr;
 620         newnp->rcv_saddr = np->rcv_saddr;
 621         newinet->dport = htons(asoc->peer.port);
 622         sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
 623
 624         /* Init the ipv4 part of the socket since we can have sockets
 625          * using v6 API for ipv4.
 626          */
 627         newinet->uc_ttl = -1;
 628         newinet->mc_loop = 1;
 629         newinet->mc_ttl = 1;
 630         newinet->mc_index = 0;
 631         newinet->mc_list = NULL;
 632
 633         if (ipv4_config.no_pmtu_disc)
 634                 newinet->pmtudisc = IP_PMTUDISC_DONT;
 635         else
 636                 newinet->pmtudisc = IP_PMTUDISC_WANT;
 637
 638 #ifdef INET_REFCNT_DEBUG
 639         atomic_inc(&inet6_sock_nr);
 640         atomic_inc(&inet_sock_nr);
 641 #endif
 642
 643         if (newsk->sk_prot->init(newsk)) {
 644                 inet_sock_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_opt *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, "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x ",
 676                    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_opt *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_opt *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_opt *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                 struct sock *sk;
 809                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
 810                 sk = sctp_opt2sk(opt);
 811                 if (type & IPV6_ADDR_LINKLOCAL) {
 812                         /* Note: Behavior similar to af_inet6.c:
 813                          *  1) Overrides previous bound_dev_if
 814                          *  2) Destructive even if bind isn't successful.
 815                          */
 816
 817                         if (addr->v6.sin6_scope_id)
 818                                 sk->sk_bound_dev_if = addr->v6.sin6_scope_id;
 819                         if (!sk->sk_bound_dev_if)
 820                                 return 0;
 821                 }
 822                 af = opt->pf->af;
 823         }
 824         return af->available(addr, opt);
 825 }
 826
 827 /* Verify that the provided sockaddr looks bindable.   Common verification,
 828  * has already been taken care of.
 829  */
 830 static int sctp_inet6_send_verify(struct sctp_opt *opt, union sctp_addr *addr)
 831 {
 832         struct sctp_af *af = NULL;
 833
 834         /* ASSERT: address family has already been verified. */
 835         if (addr->sa.sa_family != AF_INET6)
 836                 af = sctp_get_af_specific(addr->sa.sa_family);
 837         else {
 838                 struct sock *sk;
 839                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
 840                 sk = sctp_opt2sk(opt);
 841                 if (type & IPV6_ADDR_LINKLOCAL) {
 842                         /* Note: Behavior similar to af_inet6.c:
 843                          *  1) Overrides previous bound_dev_if
 844                          *  2) Destructive even if bind isn't successful.
 845                          */
 846
 847                         if (addr->v6.sin6_scope_id)
 848                                 sk->sk_bound_dev_if = addr->v6.sin6_scope_id;
 849                         if (!sk->sk_bound_dev_if)
 850                                 return 0;
 851                 }
 852                 af = opt->pf->af;
 853         }
 854
 855         return af != NULL;
 856 }
 857
 858 /* Fill in Supported Address Type information for INIT and INIT-ACK
 859  * chunks.   Note: In the future, we may want to look at sock options
 860  * to determine whether a PF_INET6 socket really wants to have IPV4
 861  * addresses.
 862  * Returns number of addresses supported.
 863  */
 864 static int sctp_inet6_supported_addrs(const struct sctp_opt *opt,
 865                                       __u16 *types)
 866 {
 867         types[0] = SCTP_PARAM_IPV4_ADDRESS;
 868         types[1] = SCTP_PARAM_IPV6_ADDRESS;
 869         return 2;
 870 }
 871
 872 static struct proto_ops inet6_seqpacket_ops = {
 873         .family     = PF_INET6,
 874         .owner      = THIS_MODULE,
 875         .release    = inet6_release,
 876         .bind       = inet6_bind,
 877         .connect    = inet_dgram_connect,
 878         .socketpair = sock_no_socketpair,
 879         .accept     = inet_accept,
 880         .getname    = inet6_getname,
 881         .poll       = sctp_poll,
 882         .ioctl      = inet6_ioctl,
 883         .listen     = sctp_inet_listen,
 884         .shutdown   = inet_shutdown,
 885         .setsockopt = inet_setsockopt,
 886         .getsockopt = inet_getsockopt,
 887         .sendmsg    = inet_sendmsg,
 888         .recvmsg    = inet_recvmsg,
 889         .mmap       = sock_no_mmap,
 890 };
 891
 892 static struct inet_protosw sctpv6_seqpacket_protosw = {
 893         .type          = SOCK_SEQPACKET,
 894         .protocol      = IPPROTO_SCTP,
 895         .prot          = &sctp_prot,
 896         .ops           = &inet6_seqpacket_ops,
 897         .capability    = -1,
 898         .no_check      = 0,
 899         .flags         = SCTP_PROTOSW_FLAG
 900 };
 901 static struct inet_protosw sctpv6_stream_protosw = {
 902         .type          = SOCK_STREAM,
 903         .protocol      = IPPROTO_SCTP,
 904         .prot          = &sctp_prot,
 905         .ops           = &inet6_seqpacket_ops,
 906         .capability    = -1,
 907         .no_check      = 0,
 908         .flags         = SCTP_PROTOSW_FLAG,
 909 };
 910
 911 static int sctp6_rcv(struct sk_buff **pskb, unsigned int *nhoffp)
 912 {
 913         return sctp_rcv(*pskb) ? -1 : 0;
 914 }
 915
 916 static struct inet6_protocol sctpv6_protocol = {
 917         .handler      = sctp6_rcv,
 918         .err_handler  = sctp_v6_err,
 919         .flags        = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
 920 };
 921
 922 static struct sctp_af sctp_ipv6_specific = {
 923         .sctp_xmit       = sctp_v6_xmit,
 924         .setsockopt      = ipv6_setsockopt,
 925         .getsockopt      = ipv6_getsockopt,
 926         .get_dst         = sctp_v6_get_dst,
 927         .get_saddr       = sctp_v6_get_saddr,
 928         .copy_addrlist   = sctp_v6_copy_addrlist,
 929         .from_skb        = sctp_v6_from_skb,
 930         .from_sk         = sctp_v6_from_sk,
 931         .to_sk_saddr     = sctp_v6_to_sk_saddr,
 932         .to_sk_daddr     = sctp_v6_to_sk_daddr,
 933         .from_addr_param = sctp_v6_from_addr_param,
 934         .to_addr_param   = sctp_v6_to_addr_param,
 935         .dst_saddr       = sctp_v6_dst_saddr,
 936         .cmp_addr        = sctp_v6_cmp_addr,
 937         .scope           = sctp_v6_scope,
 938         .addr_valid      = sctp_v6_addr_valid,
 939         .inaddr_any      = sctp_v6_inaddr_any,
 940         .is_any          = sctp_v6_is_any,
 941         .available       = sctp_v6_available,
 942         .skb_iif         = sctp_v6_skb_iif,
 943         .is_ce           = sctp_v6_is_ce,
 944         .seq_dump_addr   = sctp_v6_seq_dump_addr,
 945         .net_header_len  = sizeof(struct ipv6hdr),
 946         .sockaddr_len    = sizeof(struct sockaddr_in6),
 947         .sa_family       = AF_INET6,
 948 };
 949
 950 static struct sctp_pf sctp_pf_inet6_specific = {
 951         .event_msgname = sctp_inet6_event_msgname,
 952         .skb_msgname   = sctp_inet6_skb_msgname,
 953         .af_supported  = sctp_inet6_af_supported,
 954         .cmp_addr      = sctp_inet6_cmp_addr,
 955         .bind_verify   = sctp_inet6_bind_verify,
 956         .send_verify   = sctp_inet6_send_verify,
 957         .supported_addrs = sctp_inet6_supported_addrs,
 958         .create_accept_sk = sctp_v6_create_accept_sk,
 959         .addr_v4map    = sctp_v6_addr_v4map,
 960         .af            = &sctp_ipv6_specific,
 961 };
 962
 963 /* Initialize IPv6 support and register with inet6 stack.  */
 964 int sctp_v6_init(void)
 965 {
 966         /* Register inet6 protocol. */
 967         if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
 968                 return -EAGAIN;
 969
 970         /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
 971         inet6_register_protosw(&sctpv6_seqpacket_protosw);
 972         inet6_register_protosw(&sctpv6_stream_protosw);
 973
 974         /* Register the SCTP specific PF_INET6 functions. */
 975         sctp_register_pf(&sctp_pf_inet6_specific, PF_INET6);
 976
 977         /* Register the SCTP specific AF_INET6 functions. */
 978         sctp_register_af(&sctp_ipv6_specific);
 979
 980         /* Register notifier for inet6 address additions/deletions. */
 981         register_inet6addr_notifier(&sctp_inetaddr_notifier);
 982
 983         return 0;
 984 }
 985
 986 /* IPv6 specific exit support. */
 987 void sctp_v6_exit(void)
 988 {
 989         list_del(&sctp_ipv6_specific.list);
 990         inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
 991         inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
 992         inet6_unregister_protosw(&sctpv6_stream_protosw);
 993         unregister_inet6addr_notifier(&sctp_inetaddr_notifier);
 994 }