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:%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x "
 184                           "dst:%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
 185                           __FUNCTION__, skb, skb->len,
 186                           NIP6(fl.fl6_src), NIP6(fl.fl6_dst));
 187
 188         SCTP_INC_STATS(SCTP_MIB_OUTSCTPPACKS);
 189
 190         return ip6_xmit(sk, skb, &fl, np->opt, ipfragok);
 191 }
 192
 193 /* Returns the dst cache entry for the given source and destination ip
 194  * addresses.
 195  */
 196 static struct dst_entry *sctp_v6_get_dst(struct sctp_association *asoc,
 197                                          union sctp_addr *daddr,
 198                                          union sctp_addr *saddr)
 199 {
 200         struct dst_entry *dst;
 201         struct flowi fl;
 202
 203         memset(&fl, 0, sizeof(fl));
 204         ipv6_addr_copy(&fl.fl6_dst, &daddr->v6.sin6_addr);
 205         if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
 206                 fl.oif = daddr->v6.sin6_scope_id;
 207
 208
 209         SCTP_DEBUG_PRINTK("%s: DST=%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x ",
 210                           __FUNCTION__, NIP6(fl.fl6_dst));
 211
 212         if (saddr) {
 213                 ipv6_addr_copy(&fl.fl6_src, &saddr->v6.sin6_addr);
 214                 SCTP_DEBUG_PRINTK(
 215                         "SRC=%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x - ",
 216                         NIP6(fl.fl6_src));
 217         }
 218
 219         dst = ip6_route_output(NULL, &fl);
 220         if (dst) {
 221                 struct rt6_info *rt;
 222                 rt = (struct rt6_info *)dst;
 223                 SCTP_DEBUG_PRINTK(
 224                         "rt6_dst:%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x "
 225                         "rt6_src:%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
 226                         NIP6(rt->rt6i_dst.addr), NIP6(rt->rt6i_src.addr));
 227         } else {
 228                 SCTP_DEBUG_PRINTK("NO ROUTE\n");
 229         }
 230
 231         return dst;
 232 }
 233
 234 /* Returns the number of consecutive initial bits that match in the 2 ipv6
 235  * addresses.
 236  */
 237 static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
 238                                          union sctp_addr *s2)
 239 {
 240         struct in6_addr *a1 = &s1->v6.sin6_addr;
 241         struct in6_addr *a2 = &s2->v6.sin6_addr;
 242         int i, j;
 243
 244         for (i = 0; i < 4 ; i++) {
 245                 __u32 a1xora2;
 246
 247                 a1xora2 = a1->s6_addr32[i] ^ a2->s6_addr32[i];
 248
 249                 if ((j = fls(ntohl(a1xora2))))
 250                         return (i * 32 + 32 - j);
 251         }
 252
 253         return (i*32);
 254 }
 255
 256 /* Fills in the source address(saddr) based on the destination address(daddr)
 257  * and asoc's bind address list.
 258  */
 259 static void sctp_v6_get_saddr(struct sctp_association *asoc,
 260                               struct dst_entry *dst,
 261                               union sctp_addr *daddr,
 262                               union sctp_addr *saddr)
 263 {
 264         struct sctp_bind_addr *bp;
 265         rwlock_t *addr_lock;
 266         struct sctp_sockaddr_entry *laddr;
 267         struct list_head *pos;
 268         sctp_scope_t scope;
 269         union sctp_addr *baddr = NULL;
 270         __u8 matchlen = 0;
 271         __u8 bmatchlen;
 272
 273         SCTP_DEBUG_PRINTK("%s: asoc:%p dst:%p "
 274                           "daddr:%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x ",
 275                           __FUNCTION__, asoc, dst, NIP6(daddr->v6.sin6_addr));
 276
 277         if (!asoc) {
 278                 ipv6_get_saddr(dst, &daddr->v6.sin6_addr,&saddr->v6.sin6_addr);
 279                 SCTP_DEBUG_PRINTK("saddr from ipv6_get_saddr: "
 280                                   "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
 281                                   NIP6(saddr->v6.sin6_addr));
 282                 return;
 283         }
 284
 285         scope = sctp_scope(daddr);
 286
 287         bp = &asoc->base.bind_addr;
 288         addr_lock = &asoc->base.addr_lock;
 289
 290         /* Go through the bind address list and find the best source address
 291          * that matches the scope of the destination address.
 292          */
 293         sctp_read_lock(addr_lock);
 294         list_for_each(pos, &bp->address_list) {
 295                 laddr = list_entry(pos, struct sctp_sockaddr_entry, list);
 296                 if ((laddr->a.sa.sa_family == AF_INET6) &&
 297                     (scope <= sctp_scope(&laddr->a))) {
 298                         bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
 299                         if (!baddr || (matchlen < bmatchlen)) {
 300                                 baddr = &laddr->a;
 301                                 matchlen = bmatchlen;
 302                         }
 303                 }
 304         }
 305
 306         if (baddr) {
 307                 memcpy(saddr, baddr, sizeof(union sctp_addr));
 308                 SCTP_DEBUG_PRINTK("saddr: "
 309                                   "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
 310                                   NIP6(saddr->v6.sin6_addr));
 311         } else {
 312                 printk(KERN_ERR "%s: asoc:%p Could not find a valid source "
 313                        "address for the "
 314                        "dest:%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
 315                        __FUNCTION__, asoc, NIP6(daddr->v6.sin6_addr));
 316         }
 317
 318         sctp_read_unlock(addr_lock);
 319 }
 320
 321 /* Make a copy of all potential local addresses. */
 322 static void sctp_v6_copy_addrlist(struct list_head *addrlist,
 323                                   struct net_device *dev)
 324 {
 325         struct inet6_dev *in6_dev;
 326         struct inet6_ifaddr *ifp;
 327         struct sctp_sockaddr_entry *addr;
 328
 329         read_lock(&addrconf_lock);
 330         if ((in6_dev = __in6_dev_get(dev)) == NULL) {
 331                 read_unlock(&addrconf_lock);
 332                 return;
 333         }
 334
 335         read_lock(&in6_dev->lock);
 336         for (ifp = in6_dev->addr_list; ifp; ifp = ifp->if_next) {
 337                 /* Add the address to the local list.  */
 338                 addr = t_new(struct sctp_sockaddr_entry, GFP_ATOMIC);
 339                 if (addr) {
 340                         addr->a.v6.sin6_family = AF_INET6;
 341                         addr->a.v6.sin6_port = 0;
 342                         addr->a.v6.sin6_addr = ifp->addr;
 343                         addr->a.v6.sin6_scope_id = dev->ifindex;
 344                         INIT_LIST_HEAD(&addr->list);
 345                         list_add_tail(&addr->list, addrlist);
 346                 }
 347         }
 348
 349         read_unlock(&in6_dev->lock);
 350         read_unlock(&addrconf_lock);
 351 }
 352
 353 /* Initialize a sockaddr_storage from in incoming skb. */
 354 static void sctp_v6_from_skb(union sctp_addr *addr,struct sk_buff *skb,
 355                              int is_saddr)
 356 {
 357         void *from;
 358         __u16 *port;
 359         struct sctphdr *sh;
 360
 361         port = &addr->v6.sin6_port;
 362         addr->v6.sin6_family = AF_INET6;
 363         addr->v6.sin6_flowinfo = 0; /* FIXME */
 364         addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif;
 365
 366         sh = (struct sctphdr *) skb->h.raw;
 367         if (is_saddr) {
 368                 *port  = ntohs(sh->source);
 369                 from = &skb->nh.ipv6h->saddr;
 370         } else {
 371                 *port = ntohs(sh->dest);
 372                 from = &skb->nh.ipv6h->daddr;
 373         }
 374         ipv6_addr_copy(&addr->v6.sin6_addr, from);
 375 }
 376
 377 /* Initialize an sctp_addr from a socket. */
 378 static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
 379 {
 380         addr->v6.sin6_family = AF_INET6;
 381         addr->v6.sin6_port = inet_sk(sk)->num;
 382         addr->v6.sin6_addr = inet6_sk(sk)->rcv_saddr;
 383 }
 384
 385 /* Initialize sk->sk_rcv_saddr from sctp_addr. */
 386 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
 387 {
 388         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
 389                 inet6_sk(sk)->rcv_saddr.s6_addr32[0] = 0;
 390                 inet6_sk(sk)->rcv_saddr.s6_addr32[1] = 0;
 391                 inet6_sk(sk)->rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
 392                 inet6_sk(sk)->rcv_saddr.s6_addr32[3] =
 393                         addr->v4.sin_addr.s_addr;
 394         } else {
 395                 inet6_sk(sk)->rcv_saddr = addr->v6.sin6_addr;
 396         }
 397 }
 398
 399 /* Initialize sk->sk_daddr from sctp_addr. */
 400 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
 401 {
 402         if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
 403                 inet6_sk(sk)->daddr.s6_addr32[0] = 0;
 404                 inet6_sk(sk)->daddr.s6_addr32[1] = 0;
 405                 inet6_sk(sk)->daddr.s6_addr32[2] = htonl(0x0000ffff);
 406                 inet6_sk(sk)->daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
 407         } else {
 408                 inet6_sk(sk)->daddr = addr->v6.sin6_addr;
 409         }
 410 }
 411
 412 /* Initialize a sctp_addr from an address parameter. */
 413 static void sctp_v6_from_addr_param(union sctp_addr *addr,
 414                                     union sctp_addr_param *param,
 415                                     __u16 port, int iif)
 416 {
 417         addr->v6.sin6_family = AF_INET6;
 418         addr->v6.sin6_port = port;
 419         addr->v6.sin6_flowinfo = 0; /* BUG */
 420         ipv6_addr_copy(&addr->v6.sin6_addr, &param->v6.addr);
 421         addr->v6.sin6_scope_id = iif;
 422 }
 423
 424 /* Initialize an address parameter from a sctp_addr and return the length
 425  * of the address parameter.
 426  */
 427 static int sctp_v6_to_addr_param(const union sctp_addr *addr,
 428                                  union sctp_addr_param *param)
 429 {
 430         int length = sizeof(sctp_ipv6addr_param_t);
 431
 432         param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
 433         param->v6.param_hdr.length = ntohs(length);
 434         ipv6_addr_copy(&param->v6.addr, &addr->v6.sin6_addr);
 435
 436         return length;
 437 }
 438
 439 /* Initialize a sctp_addr from a dst_entry. */
 440 static void sctp_v6_dst_saddr(union sctp_addr *addr, struct dst_entry *dst,
 441                               unsigned short port)
 442 {
 443         struct rt6_info *rt = (struct rt6_info *)dst;
 444         addr->sa.sa_family = AF_INET6;
 445         addr->v6.sin6_port = port;
 446         ipv6_addr_copy(&addr->v6.sin6_addr, &rt->rt6i_src.addr);
 447 }
 448
 449 /* Compare addresses exactly.
 450  * v4-mapped-v6 is also in consideration.
 451  */
 452 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
 453                             const union sctp_addr *addr2)
 454 {
 455         if (addr1->sa.sa_family != addr2->sa.sa_family) {
 456                 if (addr1->sa.sa_family == AF_INET &&
 457                     addr2->sa.sa_family == AF_INET6 &&
 458                     IPV6_ADDR_MAPPED == ipv6_addr_type(&addr2->v6.sin6_addr)) {
 459                         if (addr2->v6.sin6_port == addr1->v4.sin_port &&
 460                             addr2->v6.sin6_addr.s6_addr32[3] ==
 461                             addr1->v4.sin_addr.s_addr)
 462                                 return 1;
 463                 }
 464                 if (addr2->sa.sa_family == AF_INET &&
 465                     addr1->sa.sa_family == AF_INET6 &&
 466                     IPV6_ADDR_MAPPED == ipv6_addr_type(&addr1->v6.sin6_addr)) {
 467                         if (addr1->v6.sin6_port == addr2->v4.sin_port &&
 468                             addr1->v6.sin6_addr.s6_addr32[3] ==
 469                             addr2->v4.sin_addr.s_addr)
 470                                 return 1;
 471                 }
 472                 return 0;
 473         }
 474         if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
 475                 return 0;
 476         /* If this is a linklocal address, compare the scope_id. */
 477         if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) {
 478                 if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
 479                     (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) {
 480                         return 0;
 481                 }
 482         }
 483
 484         return 1;
 485 }
 486
 487 /* Initialize addr struct to INADDR_ANY. */
 488 static void sctp_v6_inaddr_any(union sctp_addr *addr, unsigned short port)
 489 {
 490         memset(addr, 0x00, sizeof(union sctp_addr));
 491         addr->v6.sin6_family = AF_INET6;
 492         addr->v6.sin6_port = port;
 493 }
 494
 495 /* Is this a wildcard address? */
 496 static int sctp_v6_is_any(const union sctp_addr *addr)
 497 {
 498         return ipv6_addr_any(&addr->v6.sin6_addr);
 499 }
 500
 501 /* Should this be available for binding?   */
 502 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
 503 {
 504         int type;
 505         struct in6_addr *in6 = (struct in6_addr *)&addr->v6.sin6_addr;
 506
 507         type = ipv6_addr_type(in6);
 508         if (IPV6_ADDR_ANY == type)
 509                 return 1;
 510         if (type == IPV6_ADDR_MAPPED) {
 511                 if (sp && !sp->v4mapped)
 512                         return 0;
 513                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
 514                         return 0;
 515                 sctp_v6_map_v4(addr);
 516                 return sctp_get_af_specific(AF_INET)->available(addr, sp);
 517         }
 518         if (!(type & IPV6_ADDR_UNICAST))
 519                 return 0;
 520
 521         return ipv6_chk_addr(in6, NULL, 0);
 522 }
 523
 524 /* This function checks if the address is a valid address to be used for
 525  * SCTP.
 526  *
 527  * Output:
 528  * Return 0 - If the address is a non-unicast or an illegal address.
 529  * Return 1 - If the address is a unicast.
 530  */
 531 static int sctp_v6_addr_valid(union sctp_addr *addr, struct sctp_sock *sp)
 532 {
 533         int ret = ipv6_addr_type(&addr->v6.sin6_addr);
 534
 535         /* Support v4-mapped-v6 address. */
 536         if (ret == IPV6_ADDR_MAPPED) {
 537                 /* Note: This routine is used in input, so v4-mapped-v6
 538                  * are disallowed here when there is no sctp_sock.
 539                  */
 540                 if (!sp || !sp->v4mapped)
 541                         return 0;
 542                 if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
 543                         return 0;
 544                 sctp_v6_map_v4(addr);
 545                 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp);
 546         }
 547
 548         /* Is this a non-unicast address */
 549         if (!(ret & IPV6_ADDR_UNICAST))
 550                 return 0;
 551
 552         return 1;
 553 }
 554
 555 /* What is the scope of 'addr'?  */
 556 static sctp_scope_t sctp_v6_scope(union sctp_addr *addr)
 557 {
 558         int v6scope;
 559         sctp_scope_t retval;
 560
 561         /* The IPv6 scope is really a set of bit fields.
 562          * See IFA_* in <net/if_inet6.h>.  Map to a generic SCTP scope.
 563          */
 564
 565         v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
 566         switch (v6scope) {
 567         case IFA_HOST:
 568                 retval = SCTP_SCOPE_LOOPBACK;
 569                 break;
 570         case IFA_LINK:
 571                 retval = SCTP_SCOPE_LINK;
 572                 break;
 573         case IFA_SITE:
 574                 retval = SCTP_SCOPE_PRIVATE;
 575                 break;
 576         default:
 577                 retval = SCTP_SCOPE_GLOBAL;
 578                 break;
 579         };
 580
 581         return retval;
 582 }
 583
 584 /* Create and initialize a new sk for the socket to be returned by accept(). */
 585 static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
 586                                              struct sctp_association *asoc)
 587 {
 588         struct inet_sock *inet = inet_sk(sk);
 589         struct sock *newsk;
 590         struct inet_sock *newinet;
 591         struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
 592         struct sctp6_sock *newsctp6sk;
 593
 594         newsk = sk_alloc(PF_INET6, GFP_KERNEL, sk->sk_prot, 1);
 595         if (!newsk)
 596                 goto out;
 597
 598         sock_init_data(NULL, newsk);
 599
 600         newsk->sk_type = SOCK_STREAM;
 601
 602         newsk->sk_prot = sk->sk_prot;
 603         newsk->sk_no_check = sk->sk_no_check;
 604         newsk->sk_reuse = sk->sk_reuse;
 605
 606         newsk->sk_destruct = inet_sock_destruct;
 607         newsk->sk_family = PF_INET6;
 608         newsk->sk_protocol = IPPROTO_SCTP;
 609         newsk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
 610         newsk->sk_shutdown = sk->sk_shutdown;
 611         sock_reset_flag(sk, SOCK_ZAPPED);
 612
 613         newsctp6sk = (struct sctp6_sock *)newsk;
 614         inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
 615
 616         newinet = inet_sk(newsk);
 617         newnp = inet6_sk(newsk);
 618
 619         memcpy(newnp, np, sizeof(struct ipv6_pinfo));
 620
 621         /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
 622          * and getpeername().
 623          */
 624         newinet->sport = inet->sport;
 625         newnp->saddr = np->saddr;
 626         newnp->rcv_saddr = np->rcv_saddr;
 627         newinet->dport = htons(asoc->peer.port);
 628         sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
 629
 630         /* Init the ipv4 part of the socket since we can have sockets
 631          * using v6 API for ipv4.
 632          */
 633         newinet->uc_ttl = -1;
 634         newinet->mc_loop = 1;
 635         newinet->mc_ttl = 1;
 636         newinet->mc_index = 0;
 637         newinet->mc_list = NULL;
 638
 639         if (ipv4_config.no_pmtu_disc)
 640                 newinet->pmtudisc = IP_PMTUDISC_DONT;
 641         else
 642                 newinet->pmtudisc = IP_PMTUDISC_WANT;
 643
 644         sk_refcnt_debug_inc(newsk);
 645
 646         if (newsk->sk_prot->init(newsk)) {
 647                 sk_common_release(newsk);
 648                 newsk = NULL;
 649         }
 650
 651 out:
 652         return newsk;
 653 }
 654
 655 /* Map v4 address to mapped v6 address */
 656 static void sctp_v6_addr_v4map(struct sctp_sock *sp, union sctp_addr *addr)
 657 {
 658         if (sp->v4mapped && AF_INET == addr->sa.sa_family)
 659                 sctp_v4_map_v6(addr);
 660 }
 661
 662 /* Where did this skb come from?  */
 663 static int sctp_v6_skb_iif(const struct sk_buff *skb)
 664 {
 665         struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb;
 666         return opt->iif;
 667 }
 668
 669 /* Was this packet marked by Explicit Congestion Notification? */
 670 static int sctp_v6_is_ce(const struct sk_buff *skb)
 671 {
 672         return *((__u32 *)(skb->nh.ipv6h)) & htonl(1<<20);
 673 }
 674
 675 /* Dump the v6 addr to the seq file. */
 676 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
 677 {
 678         seq_printf(seq, "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x ",
 679                    NIP6(addr->v6.sin6_addr));
 680 }
 681
 682 /* Initialize a PF_INET6 socket msg_name. */
 683 static void sctp_inet6_msgname(char *msgname, int *addr_len)
 684 {
 685         struct sockaddr_in6 *sin6;
 686
 687         sin6 = (struct sockaddr_in6 *)msgname;
 688         sin6->sin6_family = AF_INET6;
 689         sin6->sin6_flowinfo = 0;
 690         sin6->sin6_scope_id = 0; /*FIXME */
 691         *addr_len = sizeof(struct sockaddr_in6);
 692 }
 693
 694 /* Initialize a PF_INET msgname from a ulpevent. */
 695 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
 696                                      char *msgname, int *addrlen)
 697 {
 698         struct sockaddr_in6 *sin6, *sin6from;
 699
 700         if (msgname) {
 701                 union sctp_addr *addr;
 702                 struct sctp_association *asoc;
 703
 704                 asoc = event->asoc;
 705                 sctp_inet6_msgname(msgname, addrlen);
 706                 sin6 = (struct sockaddr_in6 *)msgname;
 707                 sin6->sin6_port = htons(asoc->peer.port);
 708                 addr = &asoc->peer.primary_addr;
 709
 710                 /* Note: If we go to a common v6 format, this code
 711                  * will change.
 712                  */
 713
 714                 /* Map ipv4 address into v4-mapped-on-v6 address.  */
 715                 if (sctp_sk(asoc->base.sk)->v4mapped &&
 716                     AF_INET == addr->sa.sa_family) {
 717                         sctp_v4_map_v6((union sctp_addr *)sin6);
 718                         sin6->sin6_addr.s6_addr32[3] =
 719                                 addr->v4.sin_addr.s_addr;
 720                         return;
 721                 }
 722
 723                 sin6from = &asoc->peer.primary_addr.v6;
 724                 ipv6_addr_copy(&sin6->sin6_addr, &sin6from->sin6_addr);
 725                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 726                         sin6->sin6_scope_id = sin6from->sin6_scope_id;
 727         }
 728 }
 729
 730 /* Initialize a msg_name from an inbound skb. */
 731 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
 732                                    int *addr_len)
 733 {
 734         struct sctphdr *sh;
 735         struct sockaddr_in6 *sin6;
 736
 737         if (msgname) {
 738                 sctp_inet6_msgname(msgname, addr_len);
 739                 sin6 = (struct sockaddr_in6 *)msgname;
 740                 sh = (struct sctphdr *)skb->h.raw;
 741                 sin6->sin6_port = sh->source;
 742
 743                 /* Map ipv4 address into v4-mapped-on-v6 address. */
 744                 if (sctp_sk(skb->sk)->v4mapped &&
 745                     skb->nh.iph->version == 4) {
 746                         sctp_v4_map_v6((union sctp_addr *)sin6);
 747                         sin6->sin6_addr.s6_addr32[3] = skb->nh.iph->saddr;
 748                         return;
 749                 }
 750
 751                 /* Otherwise, just copy the v6 address. */
 752                 ipv6_addr_copy(&sin6->sin6_addr, &skb->nh.ipv6h->saddr);
 753                 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) {
 754                         struct sctp_ulpevent *ev = sctp_skb2event(skb);
 755                         sin6->sin6_scope_id = ev->iif;
 756                 }
 757         }
 758 }
 759
 760 /* Do we support this AF? */
 761 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
 762 {
 763         switch (family) {
 764         case AF_INET6:
 765                 return 1;
 766         /* v4-mapped-v6 addresses */
 767         case AF_INET:
 768                 if (!__ipv6_only_sock(sctp_opt2sk(sp)) && sp->v4mapped)
 769                         return 1;
 770         default:
 771                 return 0;
 772         }
 773 }
 774
 775 /* Address matching with wildcards allowed.  This extra level
 776  * of indirection lets us choose whether a PF_INET6 should
 777  * disallow any v4 addresses if we so choose.
 778  */
 779 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
 780                                const union sctp_addr *addr2,
 781                                struct sctp_sock *opt)
 782 {
 783         struct sctp_af *af1, *af2;
 784
 785         af1 = sctp_get_af_specific(addr1->sa.sa_family);
 786         af2 = sctp_get_af_specific(addr2->sa.sa_family);
 787
 788         if (!af1 || !af2)
 789                 return 0;
 790         /* Today, wildcard AF_INET/AF_INET6. */
 791         if (sctp_is_any(addr1) || sctp_is_any(addr2))
 792                 return 1;
 793
 794         if (addr1->sa.sa_family != addr2->sa.sa_family)
 795                 return 0;
 796
 797         return af1->cmp_addr(addr1, addr2);
 798 }
 799
 800 /* Verify that the provided sockaddr looks bindable.   Common verification,
 801  * has already been taken care of.
 802  */
 803 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
 804 {
 805         struct sctp_af *af;
 806
 807         /* ASSERT: address family has already been verified. */
 808         if (addr->sa.sa_family != AF_INET6)
 809                 af = sctp_get_af_specific(addr->sa.sa_family);
 810         else {
 811                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
 812                 struct net_device *dev;
 813
 814                 if (type & IPV6_ADDR_LINKLOCAL) {
 815                         if (!addr->v6.sin6_scope_id)
 816                                 return 0;
 817                         dev = dev_get_by_index(addr->v6.sin6_scope_id);
 818                         if (!dev)
 819                                 return 0;
 820                         dev_put(dev);
 821                 }
 822                 af = opt->pf->af;
 823         }
 824         return af->available(addr, opt);
 825 }
 826
 827 /* Verify that the provided sockaddr looks sendable.   Common verification,
 828  * has already been taken care of.
 829  */
 830 static int sctp_inet6_send_verify(struct sctp_sock *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                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
 839                 struct net_device *dev;
 840
 841                 if (type & IPV6_ADDR_LINKLOCAL) {
 842                         if (!addr->v6.sin6_scope_id)
 843                                 return 0;
 844                         dev = dev_get_by_index(addr->v6.sin6_scope_id);
 845                         if (!dev)
 846                                 return 0;
 847                         dev_put(dev);
 848                 }
 849                 af = opt->pf->af;
 850         }
 851
 852         return af != NULL;
 853 }
 854
 855 /* Fill in Supported Address Type information for INIT and INIT-ACK
 856  * chunks.   Note: In the future, we may want to look at sock options
 857  * to determine whether a PF_INET6 socket really wants to have IPV4
 858  * addresses.
 859  * Returns number of addresses supported.
 860  */
 861 static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
 862                                       __u16 *types)
 863 {
 864         types[0] = SCTP_PARAM_IPV4_ADDRESS;
 865         types[1] = SCTP_PARAM_IPV6_ADDRESS;
 866         return 2;
 867 }
 868
 869 static struct proto_ops inet6_seqpacket_ops = {
 870         .family     = PF_INET6,
 871         .owner      = THIS_MODULE,
 872         .release    = inet6_release,
 873         .bind       = inet6_bind,
 874         .connect    = inet_dgram_connect,
 875         .socketpair = sock_no_socketpair,
 876         .accept     = inet_accept,
 877         .getname    = inet6_getname,
 878         .poll       = sctp_poll,
 879         .ioctl      = inet6_ioctl,
 880         .listen     = sctp_inet_listen,
 881         .shutdown   = inet_shutdown,
 882         .setsockopt = sock_common_setsockopt,
 883         .getsockopt = sock_common_getsockopt,
 884         .sendmsg    = inet_sendmsg,
 885         .recvmsg    = sock_common_recvmsg,
 886         .mmap       = sock_no_mmap,
 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, unsigned int *nhoffp)
 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         .sctp_xmit       = sctp_v6_xmit,
 921         .setsockopt      = ipv6_setsockopt,
 922         .getsockopt      = ipv6_getsockopt,
 923         .get_dst         = sctp_v6_get_dst,
 924         .get_saddr       = sctp_v6_get_saddr,
 925         .copy_addrlist   = sctp_v6_copy_addrlist,
 926         .from_skb        = sctp_v6_from_skb,
 927         .from_sk         = sctp_v6_from_sk,
 928         .to_sk_saddr     = sctp_v6_to_sk_saddr,
 929         .to_sk_daddr     = sctp_v6_to_sk_daddr,
 930         .from_addr_param = sctp_v6_from_addr_param,
 931         .to_addr_param   = sctp_v6_to_addr_param,
 932         .dst_saddr       = sctp_v6_dst_saddr,
 933         .cmp_addr        = sctp_v6_cmp_addr,
 934         .scope           = sctp_v6_scope,
 935         .addr_valid      = sctp_v6_addr_valid,
 936         .inaddr_any      = sctp_v6_inaddr_any,
 937         .is_any          = sctp_v6_is_any,
 938         .available       = sctp_v6_available,
 939         .skb_iif         = sctp_v6_skb_iif,
 940         .is_ce           = sctp_v6_is_ce,
 941         .seq_dump_addr   = sctp_v6_seq_dump_addr,
 942         .net_header_len  = sizeof(struct ipv6hdr),
 943         .sockaddr_len    = sizeof(struct sockaddr_in6),
 944         .sa_family       = AF_INET6,
 945 };
 946
 947 static struct sctp_pf sctp_pf_inet6_specific = {
 948         .event_msgname = sctp_inet6_event_msgname,
 949         .skb_msgname   = sctp_inet6_skb_msgname,
 950         .af_supported  = sctp_inet6_af_supported,
 951         .cmp_addr      = sctp_inet6_cmp_addr,
 952         .bind_verify   = sctp_inet6_bind_verify,
 953         .send_verify   = sctp_inet6_send_verify,
 954         .supported_addrs = sctp_inet6_supported_addrs,
 955         .create_accept_sk = sctp_v6_create_accept_sk,
 956         .addr_v4map    = sctp_v6_addr_v4map,
 957         .af            = &sctp_ipv6_specific,
 958 };
 959
 960 /* Initialize IPv6 support and register with inet6 stack.  */
 961 int sctp_v6_init(void)
 962 {
 963         int rc = proto_register(&sctpv6_prot, 1);
 964
 965         if (rc)
 966                 goto out;
 967         /* Register inet6 protocol. */
 968         rc = -EAGAIN;
 969         if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
 970                 goto out_unregister_sctp_proto;
 971
 972         /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
 973         inet6_register_protosw(&sctpv6_seqpacket_protosw);
 974         inet6_register_protosw(&sctpv6_stream_protosw);
 975
 976         /* Register the SCTP specific PF_INET6 functions. */
 977         sctp_register_pf(&sctp_pf_inet6_specific, PF_INET6);
 978
 979         /* Register the SCTP specific AF_INET6 functions. */
 980         sctp_register_af(&sctp_ipv6_specific);
 981
 982         /* Register notifier for inet6 address additions/deletions. */
 983         register_inet6addr_notifier(&sctp_inet6addr_notifier);
 984         rc = 0;
 985 out:
 986         return rc;
 987 out_unregister_sctp_proto:
 988         proto_unregister(&sctpv6_prot);
 989         goto out;
 990 }
 991
 992 /* IPv6 specific exit support. */
 993 void sctp_v6_exit(void)
 994 {
 995         list_del(&sctp_ipv6_specific.list);
 996         inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
 997         inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
 998         inet6_unregister_protosw(&sctpv6_stream_protosw);
 999         unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1000         proto_unregister(&sctpv6_prot);
1001 }