linux/net/sctp/ipv6.c
<<
>>
Prefs
   1/* SCTP kernel implementation
   2 * (C) Copyright IBM Corp. 2002, 2004
   3 * Copyright (c) 2001 Nokia, Inc.
   4 * Copyright (c) 2001 La Monte H.P. Yarroll
   5 * Copyright (c) 2002-2003 Intel Corp.
   6 *
   7 * This file is part of the SCTP kernel implementation
   8 *
   9 * SCTP over IPv6.
  10 *
  11 * This SCTP implementation is free software;
  12 * you can redistribute it and/or modify it under the terms of
  13 * the GNU General Public License as published by
  14 * the Free Software Foundation; either version 2, or (at your option)
  15 * any later version.
  16 *
  17 * This SCTP implementation is distributed in the hope that it
  18 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
  19 *                 ************************
  20 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  21 * See the GNU General Public License for more details.
  22 *
  23 * You should have received a copy of the GNU General Public License
  24 * along with GNU CC; see the file COPYING.  If not, write to
  25 * the Free Software Foundation, 59 Temple Place - Suite 330,
  26 * Boston, MA 02111-1307, USA.
  27 *
  28 * Please send any bug reports or fixes you make to the
  29 * email address(es):
  30 *    lksctp developers <lksctp-developers@lists.sourceforge.net>
  31 *
  32 * Or submit a bug report through the following website:
  33 *    http://www.sf.net/projects/lksctp
  34 *
  35 * Written or modified by:
  36 *    Le Yanqun             <yanqun.le@nokia.com>
  37 *    Hui Huang             <hui.huang@nokia.com>
  38 *    La Monte H.P. Yarroll <piggy@acm.org>
  39 *    Sridhar Samudrala     <sri@us.ibm.com>
  40 *    Jon Grimm             <jgrimm@us.ibm.com>
  41 *    Ardelle Fan           <ardelle.fan@intel.com>
  42 *
  43 * Based on:
  44 *      linux/net/ipv6/tcp_ipv6.c
  45 *
  46 * Any bugs reported given to us we will try to fix... any fixes shared will
  47 * be incorporated into the next SCTP release.
  48 */
  49
  50#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  51
  52#include <linux/module.h>
  53#include <linux/errno.h>
  54#include <linux/types.h>
  55#include <linux/socket.h>
  56#include <linux/sockios.h>
  57#include <linux/net.h>
  58#include <linux/in.h>
  59#include <linux/in6.h>
  60#include <linux/netdevice.h>
  61#include <linux/init.h>
  62#include <linux/ipsec.h>
  63#include <linux/slab.h>
  64
  65#include <linux/ipv6.h>
  66#include <linux/icmpv6.h>
  67#include <linux/random.h>
  68#include <linux/seq_file.h>
  69
  70#include <net/protocol.h>
  71#include <net/ndisc.h>
  72#include <net/ip.h>
  73#include <net/ipv6.h>
  74#include <net/transp_v6.h>
  75#include <net/addrconf.h>
  76#include <net/ip6_route.h>
  77#include <net/inet_common.h>
  78#include <net/inet_ecn.h>
  79#include <net/sctp/sctp.h>
  80
  81#include <asm/uaccess.h>
  82
  83static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
  84                                         union sctp_addr *s2);
  85static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr,
  86                              __be16 port);
  87static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
  88                            const union sctp_addr *addr2);
  89
  90/* Event handler for inet6 address addition/deletion events.
  91 * The sctp_local_addr_list needs to be protocted by a spin lock since
  92 * multiple notifiers (say IPv4 and IPv6) may be running at the same
  93 * time and thus corrupt the list.
  94 * The reader side is protected with RCU.
  95 */
  96static int sctp_inet6addr_event(struct notifier_block *this, unsigned long ev,
  97                                void *ptr)
  98{
  99        struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
 100        struct sctp_sockaddr_entry *addr = NULL;
 101        struct sctp_sockaddr_entry *temp;
 102        int found = 0;
 103
 104        switch (ev) {
 105        case NETDEV_UP:
 106                addr = kmalloc(sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC);
 107                if (addr) {
 108                        addr->a.v6.sin6_family = AF_INET6;
 109                        addr->a.v6.sin6_port = 0;
 110                        addr->a.v6.sin6_addr = ifa->addr;
 111                        addr->a.v6.sin6_scope_id = ifa->idev->dev->ifindex;
 112                        addr->valid = 1;
 113                        spin_lock_bh(&sctp_local_addr_lock);
 114                        list_add_tail_rcu(&addr->list, &sctp_local_addr_list);
 115                        sctp_addr_wq_mgmt(addr, SCTP_ADDR_NEW);
 116                        spin_unlock_bh(&sctp_local_addr_lock);
 117                }
 118                break;
 119        case NETDEV_DOWN:
 120                spin_lock_bh(&sctp_local_addr_lock);
 121                list_for_each_entry_safe(addr, temp,
 122                                        &sctp_local_addr_list, list) {
 123                        if (addr->a.sa.sa_family == AF_INET6 &&
 124                                        ipv6_addr_equal(&addr->a.v6.sin6_addr,
 125                                                &ifa->addr)) {
 126                                sctp_addr_wq_mgmt(addr, SCTP_ADDR_DEL);
 127                                found = 1;
 128                                addr->valid = 0;
 129                                list_del_rcu(&addr->list);
 130                                break;
 131                        }
 132                }
 133                spin_unlock_bh(&sctp_local_addr_lock);
 134                if (found)
 135                        kfree_rcu(addr, rcu);
 136                break;
 137        }
 138
 139        return NOTIFY_DONE;
 140}
 141
 142static struct notifier_block sctp_inet6addr_notifier = {
 143        .notifier_call = sctp_inet6addr_event,
 144};
 145
 146/* ICMP error handler. */
 147SCTP_STATIC void sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 148                             u8 type, u8 code, int offset, __be32 info)
 149{
 150        struct inet6_dev *idev;
 151        struct sock *sk;
 152        struct sctp_association *asoc;
 153        struct sctp_transport *transport;
 154        struct ipv6_pinfo *np;
 155        sk_buff_data_t saveip, savesctp;
 156        int err;
 157
 158        idev = in6_dev_get(skb->dev);
 159
 160        /* Fix up skb to look at the embedded net header. */
 161        saveip   = skb->network_header;
 162        savesctp = skb->transport_header;
 163        skb_reset_network_header(skb);
 164        skb_set_transport_header(skb, offset);
 165        sk = sctp_err_lookup(AF_INET6, skb, sctp_hdr(skb), &asoc, &transport);
 166        /* Put back, the original pointers. */
 167        skb->network_header   = saveip;
 168        skb->transport_header = savesctp;
 169        if (!sk) {
 170                ICMP6_INC_STATS_BH(dev_net(skb->dev), idev, ICMP6_MIB_INERRORS);
 171                goto out;
 172        }
 173
 174        /* Warning:  The sock lock is held.  Remember to call
 175         * sctp_err_finish!
 176         */
 177
 178        switch (type) {
 179        case ICMPV6_PKT_TOOBIG:
 180                sctp_icmp_frag_needed(sk, asoc, transport, ntohl(info));
 181                goto out_unlock;
 182        case ICMPV6_PARAMPROB:
 183                if (ICMPV6_UNK_NEXTHDR == code) {
 184                        sctp_icmp_proto_unreachable(sk, asoc, transport);
 185                        goto out_unlock;
 186                }
 187                break;
 188        case NDISC_REDIRECT:
 189                sctp_icmp_redirect(sk, transport, skb);
 190                break;
 191        default:
 192                break;
 193        }
 194
 195        np = inet6_sk(sk);
 196        icmpv6_err_convert(type, code, &err);
 197        if (!sock_owned_by_user(sk) && np->recverr) {
 198                sk->sk_err = err;
 199                sk->sk_error_report(sk);
 200        } else {  /* Only an error on timeout */
 201                sk->sk_err_soft = err;
 202        }
 203
 204out_unlock:
 205        sctp_err_finish(sk, asoc);
 206out:
 207        if (likely(idev != NULL))
 208                in6_dev_put(idev);
 209}
 210
 211/* Based on tcp_v6_xmit() in tcp_ipv6.c. */
 212static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *transport)
 213{
 214        struct sock *sk = skb->sk;
 215        struct ipv6_pinfo *np = inet6_sk(sk);
 216        struct flowi6 fl6;
 217
 218        memset(&fl6, 0, sizeof(fl6));
 219
 220        fl6.flowi6_proto = sk->sk_protocol;
 221
 222        /* Fill in the dest address from the route entry passed with the skb
 223         * and the source address from the transport.
 224         */
 225        fl6.daddr = transport->ipaddr.v6.sin6_addr;
 226        fl6.saddr = transport->saddr.v6.sin6_addr;
 227
 228        fl6.flowlabel = np->flow_label;
 229        IP6_ECN_flow_xmit(sk, fl6.flowlabel);
 230        if (ipv6_addr_type(&fl6.saddr) & IPV6_ADDR_LINKLOCAL)
 231                fl6.flowi6_oif = transport->saddr.v6.sin6_scope_id;
 232        else
 233                fl6.flowi6_oif = sk->sk_bound_dev_if;
 234
 235        if (np->opt && np->opt->srcrt) {
 236                struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
 237                fl6.daddr = *rt0->addr;
 238        }
 239
 240        SCTP_DEBUG_PRINTK("%s: skb:%p, len:%d, src:%pI6 dst:%pI6\n",
 241                          __func__, skb, skb->len,
 242                          &fl6.saddr, &fl6.daddr);
 243
 244        SCTP_INC_STATS(SCTP_MIB_OUTSCTPPACKS);
 245
 246        if (!(transport->param_flags & SPP_PMTUD_ENABLE))
 247                skb->local_df = 1;
 248
 249        return ip6_xmit(sk, skb, &fl6, np->opt, np->tclass);
 250}
 251
 252/* Returns the dst cache entry for the given source and destination ip
 253 * addresses.
 254 */
 255static void sctp_v6_get_dst(struct sctp_transport *t, union sctp_addr *saddr,
 256                            struct flowi *fl, struct sock *sk)
 257{
 258        struct sctp_association *asoc = t->asoc;
 259        struct dst_entry *dst = NULL;
 260        struct flowi6 *fl6 = &fl->u.ip6;
 261        struct sctp_bind_addr *bp;
 262        struct sctp_sockaddr_entry *laddr;
 263        union sctp_addr *baddr = NULL;
 264        union sctp_addr *daddr = &t->ipaddr;
 265        union sctp_addr dst_saddr;
 266        __u8 matchlen = 0;
 267        __u8 bmatchlen;
 268        sctp_scope_t scope;
 269
 270        memset(fl6, 0, sizeof(struct flowi6));
 271        fl6->daddr = daddr->v6.sin6_addr;
 272        fl6->fl6_dport = daddr->v6.sin6_port;
 273        fl6->flowi6_proto = IPPROTO_SCTP;
 274        if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
 275                fl6->flowi6_oif = daddr->v6.sin6_scope_id;
 276
 277        SCTP_DEBUG_PRINTK("%s: DST=%pI6 ", __func__, &fl6->daddr);
 278
 279        if (asoc)
 280                fl6->fl6_sport = htons(asoc->base.bind_addr.port);
 281
 282        if (saddr) {
 283                fl6->saddr = saddr->v6.sin6_addr;
 284                fl6->fl6_sport = saddr->v6.sin6_port;
 285                SCTP_DEBUG_PRINTK("SRC=%pI6 - ", &fl6->saddr);
 286        }
 287
 288        dst = ip6_dst_lookup_flow(sk, fl6, NULL, false);
 289        if (!asoc || saddr)
 290                goto out;
 291
 292        bp = &asoc->base.bind_addr;
 293        scope = sctp_scope(daddr);
 294        /* ip6_dst_lookup has filled in the fl6->saddr for us.  Check
 295         * to see if we can use it.
 296         */
 297        if (!IS_ERR(dst)) {
 298                /* Walk through the bind address list and look for a bind
 299                 * address that matches the source address of the returned dst.
 300                 */
 301                sctp_v6_to_addr(&dst_saddr, &fl6->saddr, htons(bp->port));
 302                rcu_read_lock();
 303                list_for_each_entry_rcu(laddr, &bp->address_list, list) {
 304                        if (!laddr->valid || (laddr->state != SCTP_ADDR_SRC))
 305                                continue;
 306
 307                        /* Do not compare against v4 addrs */
 308                        if ((laddr->a.sa.sa_family == AF_INET6) &&
 309                            (sctp_v6_cmp_addr(&dst_saddr, &laddr->a))) {
 310                                rcu_read_unlock();
 311                                goto out;
 312                        }
 313                }
 314                rcu_read_unlock();
 315                /* None of the bound addresses match the source address of the
 316                 * dst. So release it.
 317                 */
 318                dst_release(dst);
 319                dst = NULL;
 320        }
 321
 322        /* Walk through the bind address list and try to get the
 323         * best source address for a given destination.
 324         */
 325        rcu_read_lock();
 326        list_for_each_entry_rcu(laddr, &bp->address_list, list) {
 327                if (!laddr->valid && laddr->state != SCTP_ADDR_SRC)
 328                        continue;
 329                if ((laddr->a.sa.sa_family == AF_INET6) &&
 330                    (scope <= sctp_scope(&laddr->a))) {
 331                        bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a);
 332                        if (!baddr || (matchlen < bmatchlen)) {
 333                                baddr = &laddr->a;
 334                                matchlen = bmatchlen;
 335                        }
 336                }
 337        }
 338        rcu_read_unlock();
 339        if (baddr) {
 340                fl6->saddr = baddr->v6.sin6_addr;
 341                fl6->fl6_sport = baddr->v6.sin6_port;
 342                dst = ip6_dst_lookup_flow(sk, fl6, NULL, false);
 343        }
 344
 345out:
 346        if (!IS_ERR(dst)) {
 347                struct rt6_info *rt;
 348                rt = (struct rt6_info *)dst;
 349                t->dst = dst;
 350                SCTP_DEBUG_PRINTK("rt6_dst:%pI6 rt6_src:%pI6\n",
 351                        &rt->rt6i_dst.addr, &fl6->saddr);
 352        } else {
 353                t->dst = NULL;
 354                SCTP_DEBUG_PRINTK("NO ROUTE\n");
 355        }
 356}
 357
 358/* Returns the number of consecutive initial bits that match in the 2 ipv6
 359 * addresses.
 360 */
 361static inline int sctp_v6_addr_match_len(union sctp_addr *s1,
 362                                         union sctp_addr *s2)
 363{
 364        return ipv6_addr_diff(&s1->v6.sin6_addr, &s2->v6.sin6_addr);
 365}
 366
 367/* Fills in the source address(saddr) based on the destination address(daddr)
 368 * and asoc's bind address list.
 369 */
 370static void sctp_v6_get_saddr(struct sctp_sock *sk,
 371                              struct sctp_transport *t,
 372                              struct flowi *fl)
 373{
 374        struct flowi6 *fl6 = &fl->u.ip6;
 375        union sctp_addr *saddr = &t->saddr;
 376
 377        SCTP_DEBUG_PRINTK("%s: asoc:%p dst:%p\n", __func__, t->asoc, t->dst);
 378
 379        if (t->dst) {
 380                saddr->v6.sin6_family = AF_INET6;
 381                saddr->v6.sin6_addr = fl6->saddr;
 382        }
 383}
 384
 385/* Make a copy of all potential local addresses. */
 386static void sctp_v6_copy_addrlist(struct list_head *addrlist,
 387                                  struct net_device *dev)
 388{
 389        struct inet6_dev *in6_dev;
 390        struct inet6_ifaddr *ifp;
 391        struct sctp_sockaddr_entry *addr;
 392
 393        rcu_read_lock();
 394        if ((in6_dev = __in6_dev_get(dev)) == NULL) {
 395                rcu_read_unlock();
 396                return;
 397        }
 398
 399        read_lock_bh(&in6_dev->lock);
 400        list_for_each_entry(ifp, &in6_dev->addr_list, if_list) {
 401                /* Add the address to the local list.  */
 402                addr = t_new(struct sctp_sockaddr_entry, GFP_ATOMIC);
 403                if (addr) {
 404                        addr->a.v6.sin6_family = AF_INET6;
 405                        addr->a.v6.sin6_port = 0;
 406                        addr->a.v6.sin6_addr = ifp->addr;
 407                        addr->a.v6.sin6_scope_id = dev->ifindex;
 408                        addr->valid = 1;
 409                        INIT_LIST_HEAD(&addr->list);
 410                        list_add_tail(&addr->list, addrlist);
 411                }
 412        }
 413
 414        read_unlock_bh(&in6_dev->lock);
 415        rcu_read_unlock();
 416}
 417
 418/* Initialize a sockaddr_storage from in incoming skb. */
 419static void sctp_v6_from_skb(union sctp_addr *addr,struct sk_buff *skb,
 420                             int is_saddr)
 421{
 422        __be16 *port;
 423        struct sctphdr *sh;
 424
 425        port = &addr->v6.sin6_port;
 426        addr->v6.sin6_family = AF_INET6;
 427        addr->v6.sin6_flowinfo = 0; /* FIXME */
 428        addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif;
 429
 430        sh = sctp_hdr(skb);
 431        if (is_saddr) {
 432                *port  = sh->source;
 433                addr->v6.sin6_addr = ipv6_hdr(skb)->saddr;
 434        } else {
 435                *port = sh->dest;
 436                addr->v6.sin6_addr = ipv6_hdr(skb)->daddr;
 437        }
 438}
 439
 440/* Initialize an sctp_addr from a socket. */
 441static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
 442{
 443        addr->v6.sin6_family = AF_INET6;
 444        addr->v6.sin6_port = 0;
 445        addr->v6.sin6_addr = inet6_sk(sk)->rcv_saddr;
 446}
 447
 448/* Initialize sk->sk_rcv_saddr from sctp_addr. */
 449static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk)
 450{
 451        if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
 452                inet6_sk(sk)->rcv_saddr.s6_addr32[0] = 0;
 453                inet6_sk(sk)->rcv_saddr.s6_addr32[1] = 0;
 454                inet6_sk(sk)->rcv_saddr.s6_addr32[2] = htonl(0x0000ffff);
 455                inet6_sk(sk)->rcv_saddr.s6_addr32[3] =
 456                        addr->v4.sin_addr.s_addr;
 457        } else {
 458                inet6_sk(sk)->rcv_saddr = addr->v6.sin6_addr;
 459        }
 460}
 461
 462/* Initialize sk->sk_daddr from sctp_addr. */
 463static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk)
 464{
 465        if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) {
 466                inet6_sk(sk)->daddr.s6_addr32[0] = 0;
 467                inet6_sk(sk)->daddr.s6_addr32[1] = 0;
 468                inet6_sk(sk)->daddr.s6_addr32[2] = htonl(0x0000ffff);
 469                inet6_sk(sk)->daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
 470        } else {
 471                inet6_sk(sk)->daddr = addr->v6.sin6_addr;
 472        }
 473}
 474
 475/* Initialize a sctp_addr from an address parameter. */
 476static void sctp_v6_from_addr_param(union sctp_addr *addr,
 477                                    union sctp_addr_param *param,
 478                                    __be16 port, int iif)
 479{
 480        addr->v6.sin6_family = AF_INET6;
 481        addr->v6.sin6_port = port;
 482        addr->v6.sin6_flowinfo = 0; /* BUG */
 483        addr->v6.sin6_addr = param->v6.addr;
 484        addr->v6.sin6_scope_id = iif;
 485}
 486
 487/* Initialize an address parameter from a sctp_addr and return the length
 488 * of the address parameter.
 489 */
 490static int sctp_v6_to_addr_param(const union sctp_addr *addr,
 491                                 union sctp_addr_param *param)
 492{
 493        int length = sizeof(sctp_ipv6addr_param_t);
 494
 495        param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS;
 496        param->v6.param_hdr.length = htons(length);
 497        param->v6.addr = addr->v6.sin6_addr;
 498
 499        return length;
 500}
 501
 502/* Initialize a sctp_addr from struct in6_addr. */
 503static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr,
 504                              __be16 port)
 505{
 506        addr->sa.sa_family = AF_INET6;
 507        addr->v6.sin6_port = port;
 508        addr->v6.sin6_addr = *saddr;
 509}
 510
 511/* Compare addresses exactly.
 512 * v4-mapped-v6 is also in consideration.
 513 */
 514static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
 515                            const union sctp_addr *addr2)
 516{
 517        if (addr1->sa.sa_family != addr2->sa.sa_family) {
 518                if (addr1->sa.sa_family == AF_INET &&
 519                    addr2->sa.sa_family == AF_INET6 &&
 520                    ipv6_addr_v4mapped(&addr2->v6.sin6_addr)) {
 521                        if (addr2->v6.sin6_port == addr1->v4.sin_port &&
 522                            addr2->v6.sin6_addr.s6_addr32[3] ==
 523                            addr1->v4.sin_addr.s_addr)
 524                                return 1;
 525                }
 526                if (addr2->sa.sa_family == AF_INET &&
 527                    addr1->sa.sa_family == AF_INET6 &&
 528                    ipv6_addr_v4mapped(&addr1->v6.sin6_addr)) {
 529                        if (addr1->v6.sin6_port == addr2->v4.sin_port &&
 530                            addr1->v6.sin6_addr.s6_addr32[3] ==
 531                            addr2->v4.sin_addr.s_addr)
 532                                return 1;
 533                }
 534                return 0;
 535        }
 536        if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr))
 537                return 0;
 538        /* If this is a linklocal address, compare the scope_id. */
 539        if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) {
 540                if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id &&
 541                    (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) {
 542                        return 0;
 543                }
 544        }
 545
 546        return 1;
 547}
 548
 549/* Initialize addr struct to INADDR_ANY. */
 550static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port)
 551{
 552        memset(addr, 0x00, sizeof(union sctp_addr));
 553        addr->v6.sin6_family = AF_INET6;
 554        addr->v6.sin6_port = port;
 555}
 556
 557/* Is this a wildcard address? */
 558static int sctp_v6_is_any(const union sctp_addr *addr)
 559{
 560        return ipv6_addr_any(&addr->v6.sin6_addr);
 561}
 562
 563/* Should this be available for binding?   */
 564static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp)
 565{
 566        int type;
 567        const struct in6_addr *in6 = (const struct in6_addr *)&addr->v6.sin6_addr;
 568
 569        type = ipv6_addr_type(in6);
 570        if (IPV6_ADDR_ANY == type)
 571                return 1;
 572        if (type == IPV6_ADDR_MAPPED) {
 573                if (sp && !sp->v4mapped)
 574                        return 0;
 575                if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
 576                        return 0;
 577                sctp_v6_map_v4(addr);
 578                return sctp_get_af_specific(AF_INET)->available(addr, sp);
 579        }
 580        if (!(type & IPV6_ADDR_UNICAST))
 581                return 0;
 582
 583        return ipv6_chk_addr(&init_net, in6, NULL, 0);
 584}
 585
 586/* This function checks if the address is a valid address to be used for
 587 * SCTP.
 588 *
 589 * Output:
 590 * Return 0 - If the address is a non-unicast or an illegal address.
 591 * Return 1 - If the address is a unicast.
 592 */
 593static int sctp_v6_addr_valid(union sctp_addr *addr,
 594                              struct sctp_sock *sp,
 595                              const struct sk_buff *skb)
 596{
 597        int ret = ipv6_addr_type(&addr->v6.sin6_addr);
 598
 599        /* Support v4-mapped-v6 address. */
 600        if (ret == IPV6_ADDR_MAPPED) {
 601                /* Note: This routine is used in input, so v4-mapped-v6
 602                 * are disallowed here when there is no sctp_sock.
 603                 */
 604                if (!sp || !sp->v4mapped)
 605                        return 0;
 606                if (sp && ipv6_only_sock(sctp_opt2sk(sp)))
 607                        return 0;
 608                sctp_v6_map_v4(addr);
 609                return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb);
 610        }
 611
 612        /* Is this a non-unicast address */
 613        if (!(ret & IPV6_ADDR_UNICAST))
 614                return 0;
 615
 616        return 1;
 617}
 618
 619/* What is the scope of 'addr'?  */
 620static sctp_scope_t sctp_v6_scope(union sctp_addr *addr)
 621{
 622        int v6scope;
 623        sctp_scope_t retval;
 624
 625        /* The IPv6 scope is really a set of bit fields.
 626         * See IFA_* in <net/if_inet6.h>.  Map to a generic SCTP scope.
 627         */
 628
 629        v6scope = ipv6_addr_scope(&addr->v6.sin6_addr);
 630        switch (v6scope) {
 631        case IFA_HOST:
 632                retval = SCTP_SCOPE_LOOPBACK;
 633                break;
 634        case IFA_LINK:
 635                retval = SCTP_SCOPE_LINK;
 636                break;
 637        case IFA_SITE:
 638                retval = SCTP_SCOPE_PRIVATE;
 639                break;
 640        default:
 641                retval = SCTP_SCOPE_GLOBAL;
 642                break;
 643        }
 644
 645        return retval;
 646}
 647
 648/* Create and initialize a new sk for the socket to be returned by accept(). */
 649static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
 650                                             struct sctp_association *asoc)
 651{
 652        struct sock *newsk;
 653        struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
 654        struct sctp6_sock *newsctp6sk;
 655
 656        newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot);
 657        if (!newsk)
 658                goto out;
 659
 660        sock_init_data(NULL, newsk);
 661
 662        sctp_copy_sock(newsk, sk, asoc);
 663        sock_reset_flag(sk, SOCK_ZAPPED);
 664
 665        newsctp6sk = (struct sctp6_sock *)newsk;
 666        inet_sk(newsk)->pinet6 = &newsctp6sk->inet6;
 667
 668        sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped;
 669
 670        newnp = inet6_sk(newsk);
 671
 672        memcpy(newnp, np, sizeof(struct ipv6_pinfo));
 673
 674        /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
 675         * and getpeername().
 676         */
 677        sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk);
 678
 679        sk_refcnt_debug_inc(newsk);
 680
 681        if (newsk->sk_prot->init(newsk)) {
 682                sk_common_release(newsk);
 683                newsk = NULL;
 684        }
 685
 686out:
 687        return newsk;
 688}
 689
 690/* Map v4 address to mapped v6 address */
 691static void sctp_v6_addr_v4map(struct sctp_sock *sp, union sctp_addr *addr)
 692{
 693        if (sp->v4mapped && AF_INET == addr->sa.sa_family)
 694                sctp_v4_map_v6(addr);
 695}
 696
 697/* Where did this skb come from?  */
 698static int sctp_v6_skb_iif(const struct sk_buff *skb)
 699{
 700        struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb;
 701        return opt->iif;
 702}
 703
 704/* Was this packet marked by Explicit Congestion Notification? */
 705static int sctp_v6_is_ce(const struct sk_buff *skb)
 706{
 707        return *((__u32 *)(ipv6_hdr(skb))) & htonl(1 << 20);
 708}
 709
 710/* Dump the v6 addr to the seq file. */
 711static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr)
 712{
 713        seq_printf(seq, "%pI6 ", &addr->v6.sin6_addr);
 714}
 715
 716static void sctp_v6_ecn_capable(struct sock *sk)
 717{
 718        inet6_sk(sk)->tclass |= INET_ECN_ECT_0;
 719}
 720
 721/* Initialize a PF_INET6 socket msg_name. */
 722static void sctp_inet6_msgname(char *msgname, int *addr_len)
 723{
 724        struct sockaddr_in6 *sin6;
 725
 726        sin6 = (struct sockaddr_in6 *)msgname;
 727        sin6->sin6_family = AF_INET6;
 728        sin6->sin6_flowinfo = 0;
 729        sin6->sin6_scope_id = 0; /*FIXME */
 730        *addr_len = sizeof(struct sockaddr_in6);
 731}
 732
 733/* Initialize a PF_INET msgname from a ulpevent. */
 734static void sctp_inet6_event_msgname(struct sctp_ulpevent *event,
 735                                     char *msgname, int *addrlen)
 736{
 737        struct sockaddr_in6 *sin6, *sin6from;
 738
 739        if (msgname) {
 740                union sctp_addr *addr;
 741                struct sctp_association *asoc;
 742
 743                asoc = event->asoc;
 744                sctp_inet6_msgname(msgname, addrlen);
 745                sin6 = (struct sockaddr_in6 *)msgname;
 746                sin6->sin6_port = htons(asoc->peer.port);
 747                addr = &asoc->peer.primary_addr;
 748
 749                /* Note: If we go to a common v6 format, this code
 750                 * will change.
 751                 */
 752
 753                /* Map ipv4 address into v4-mapped-on-v6 address.  */
 754                if (sctp_sk(asoc->base.sk)->v4mapped &&
 755                    AF_INET == addr->sa.sa_family) {
 756                        sctp_v4_map_v6((union sctp_addr *)sin6);
 757                        sin6->sin6_addr.s6_addr32[3] =
 758                                addr->v4.sin_addr.s_addr;
 759                        return;
 760                }
 761
 762                sin6from = &asoc->peer.primary_addr.v6;
 763                sin6->sin6_addr = sin6from->sin6_addr;
 764                if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 765                        sin6->sin6_scope_id = sin6from->sin6_scope_id;
 766        }
 767}
 768
 769/* Initialize a msg_name from an inbound skb. */
 770static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname,
 771                                   int *addr_len)
 772{
 773        struct sctphdr *sh;
 774        struct sockaddr_in6 *sin6;
 775
 776        if (msgname) {
 777                sctp_inet6_msgname(msgname, addr_len);
 778                sin6 = (struct sockaddr_in6 *)msgname;
 779                sh = sctp_hdr(skb);
 780                sin6->sin6_port = sh->source;
 781
 782                /* Map ipv4 address into v4-mapped-on-v6 address. */
 783                if (sctp_sk(skb->sk)->v4mapped &&
 784                    ip_hdr(skb)->version == 4) {
 785                        sctp_v4_map_v6((union sctp_addr *)sin6);
 786                        sin6->sin6_addr.s6_addr32[3] = ip_hdr(skb)->saddr;
 787                        return;
 788                }
 789
 790                /* Otherwise, just copy the v6 address. */
 791                sin6->sin6_addr = ipv6_hdr(skb)->saddr;
 792                if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) {
 793                        struct sctp_ulpevent *ev = sctp_skb2event(skb);
 794                        sin6->sin6_scope_id = ev->iif;
 795                }
 796        }
 797}
 798
 799/* Do we support this AF? */
 800static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp)
 801{
 802        switch (family) {
 803        case AF_INET6:
 804                return 1;
 805        /* v4-mapped-v6 addresses */
 806        case AF_INET:
 807                if (!__ipv6_only_sock(sctp_opt2sk(sp)))
 808                        return 1;
 809        default:
 810                return 0;
 811        }
 812}
 813
 814/* Address matching with wildcards allowed.  This extra level
 815 * of indirection lets us choose whether a PF_INET6 should
 816 * disallow any v4 addresses if we so choose.
 817 */
 818static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
 819                               const union sctp_addr *addr2,
 820                               struct sctp_sock *opt)
 821{
 822        struct sctp_af *af1, *af2;
 823        struct sock *sk = sctp_opt2sk(opt);
 824
 825        af1 = sctp_get_af_specific(addr1->sa.sa_family);
 826        af2 = sctp_get_af_specific(addr2->sa.sa_family);
 827
 828        if (!af1 || !af2)
 829                return 0;
 830
 831        /* If the socket is IPv6 only, v4 addrs will not match */
 832        if (__ipv6_only_sock(sk) && af1 != af2)
 833                return 0;
 834
 835        /* Today, wildcard AF_INET/AF_INET6. */
 836        if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2))
 837                return 1;
 838
 839        if (addr1->sa.sa_family != addr2->sa.sa_family)
 840                return 0;
 841
 842        return af1->cmp_addr(addr1, addr2);
 843}
 844
 845/* Verify that the provided sockaddr looks bindable.   Common verification,
 846 * has already been taken care of.
 847 */
 848static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
 849{
 850        struct sctp_af *af;
 851
 852        /* ASSERT: address family has already been verified. */
 853        if (addr->sa.sa_family != AF_INET6)
 854                af = sctp_get_af_specific(addr->sa.sa_family);
 855        else {
 856                int type = ipv6_addr_type(&addr->v6.sin6_addr);
 857                struct net_device *dev;
 858
 859                if (type & IPV6_ADDR_LINKLOCAL) {
 860                        if (!addr->v6.sin6_scope_id)
 861                                return 0;
 862                        rcu_read_lock();
 863                        dev = dev_get_by_index_rcu(&init_net,
 864                                                   addr->v6.sin6_scope_id);
 865                        if (!dev ||
 866                            !ipv6_chk_addr(&init_net, &addr->v6.sin6_addr,
 867                                           dev, 0)) {
 868                                rcu_read_unlock();
 869                                return 0;
 870                        }
 871                        rcu_read_unlock();
 872                } else if (type == IPV6_ADDR_MAPPED) {
 873                        if (!opt->v4mapped)
 874                                return 0;
 875                }
 876
 877                af = opt->pf->af;
 878        }
 879        return af->available(addr, opt);
 880}
 881
 882/* Verify that the provided sockaddr looks sendable.   Common verification,
 883 * has already been taken care of.
 884 */
 885static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
 886{
 887        struct sctp_af *af = NULL;
 888
 889        /* ASSERT: address family has already been verified. */
 890        if (addr->sa.sa_family != AF_INET6)
 891                af = sctp_get_af_specific(addr->sa.sa_family);
 892        else {
 893                int type = ipv6_addr_type(&addr->v6.sin6_addr);
 894                struct net_device *dev;
 895
 896                if (type & IPV6_ADDR_LINKLOCAL) {
 897                        if (!addr->v6.sin6_scope_id)
 898                                return 0;
 899                        rcu_read_lock();
 900                        dev = dev_get_by_index_rcu(&init_net,
 901                                                   addr->v6.sin6_scope_id);
 902                        rcu_read_unlock();
 903                        if (!dev)
 904                                return 0;
 905                }
 906                af = opt->pf->af;
 907        }
 908
 909        return af != NULL;
 910}
 911
 912/* Fill in Supported Address Type information for INIT and INIT-ACK
 913 * chunks.   Note: In the future, we may want to look at sock options
 914 * to determine whether a PF_INET6 socket really wants to have IPV4
 915 * addresses.
 916 * Returns number of addresses supported.
 917 */
 918static int sctp_inet6_supported_addrs(const struct sctp_sock *opt,
 919                                      __be16 *types)
 920{
 921        types[0] = SCTP_PARAM_IPV6_ADDRESS;
 922        if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) {
 923                types[1] = SCTP_PARAM_IPV4_ADDRESS;
 924                return 2;
 925        }
 926        return 1;
 927}
 928
 929static const struct proto_ops inet6_seqpacket_ops = {
 930        .family            = PF_INET6,
 931        .owner             = THIS_MODULE,
 932        .release           = inet6_release,
 933        .bind              = inet6_bind,
 934        .connect           = inet_dgram_connect,
 935        .socketpair        = sock_no_socketpair,
 936        .accept            = inet_accept,
 937        .getname           = inet6_getname,
 938        .poll              = sctp_poll,
 939        .ioctl             = inet6_ioctl,
 940        .listen            = sctp_inet_listen,
 941        .shutdown          = inet_shutdown,
 942        .setsockopt        = sock_common_setsockopt,
 943        .getsockopt        = sock_common_getsockopt,
 944        .sendmsg           = inet_sendmsg,
 945        .recvmsg           = sock_common_recvmsg,
 946        .mmap              = sock_no_mmap,
 947#ifdef CONFIG_COMPAT
 948        .compat_setsockopt = compat_sock_common_setsockopt,
 949        .compat_getsockopt = compat_sock_common_getsockopt,
 950#endif
 951};
 952
 953static struct inet_protosw sctpv6_seqpacket_protosw = {
 954        .type          = SOCK_SEQPACKET,
 955        .protocol      = IPPROTO_SCTP,
 956        .prot          = &sctpv6_prot,
 957        .ops           = &inet6_seqpacket_ops,
 958        .no_check      = 0,
 959        .flags         = SCTP_PROTOSW_FLAG
 960};
 961static struct inet_protosw sctpv6_stream_protosw = {
 962        .type          = SOCK_STREAM,
 963        .protocol      = IPPROTO_SCTP,
 964        .prot          = &sctpv6_prot,
 965        .ops           = &inet6_seqpacket_ops,
 966        .no_check      = 0,
 967        .flags         = SCTP_PROTOSW_FLAG,
 968};
 969
 970static int sctp6_rcv(struct sk_buff *skb)
 971{
 972        return sctp_rcv(skb) ? -1 : 0;
 973}
 974
 975static const struct inet6_protocol sctpv6_protocol = {
 976        .handler      = sctp6_rcv,
 977        .err_handler  = sctp_v6_err,
 978        .flags        = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
 979};
 980
 981static struct sctp_af sctp_af_inet6 = {
 982        .sa_family         = AF_INET6,
 983        .sctp_xmit         = sctp_v6_xmit,
 984        .setsockopt        = ipv6_setsockopt,
 985        .getsockopt        = ipv6_getsockopt,
 986        .get_dst           = sctp_v6_get_dst,
 987        .get_saddr         = sctp_v6_get_saddr,
 988        .copy_addrlist     = sctp_v6_copy_addrlist,
 989        .from_skb          = sctp_v6_from_skb,
 990        .from_sk           = sctp_v6_from_sk,
 991        .to_sk_saddr       = sctp_v6_to_sk_saddr,
 992        .to_sk_daddr       = sctp_v6_to_sk_daddr,
 993        .from_addr_param   = sctp_v6_from_addr_param,
 994        .to_addr_param     = sctp_v6_to_addr_param,
 995        .cmp_addr          = sctp_v6_cmp_addr,
 996        .scope             = sctp_v6_scope,
 997        .addr_valid        = sctp_v6_addr_valid,
 998        .inaddr_any        = sctp_v6_inaddr_any,
 999        .is_any            = sctp_v6_is_any,
1000        .available         = sctp_v6_available,
1001        .skb_iif           = sctp_v6_skb_iif,
1002        .is_ce             = sctp_v6_is_ce,
1003        .seq_dump_addr     = sctp_v6_seq_dump_addr,
1004        .ecn_capable       = sctp_v6_ecn_capable,
1005        .net_header_len    = sizeof(struct ipv6hdr),
1006        .sockaddr_len      = sizeof(struct sockaddr_in6),
1007#ifdef CONFIG_COMPAT
1008        .compat_setsockopt = compat_ipv6_setsockopt,
1009        .compat_getsockopt = compat_ipv6_getsockopt,
1010#endif
1011};
1012
1013static struct sctp_pf sctp_pf_inet6 = {
1014        .event_msgname = sctp_inet6_event_msgname,
1015        .skb_msgname   = sctp_inet6_skb_msgname,
1016        .af_supported  = sctp_inet6_af_supported,
1017        .cmp_addr      = sctp_inet6_cmp_addr,
1018        .bind_verify   = sctp_inet6_bind_verify,
1019        .send_verify   = sctp_inet6_send_verify,
1020        .supported_addrs = sctp_inet6_supported_addrs,
1021        .create_accept_sk = sctp_v6_create_accept_sk,
1022        .addr_v4map    = sctp_v6_addr_v4map,
1023        .af            = &sctp_af_inet6,
1024};
1025
1026/* Initialize IPv6 support and register with socket layer.  */
1027void sctp_v6_pf_init(void)
1028{
1029        /* Register the SCTP specific PF_INET6 functions. */
1030        sctp_register_pf(&sctp_pf_inet6, PF_INET6);
1031
1032        /* Register the SCTP specific AF_INET6 functions. */
1033        sctp_register_af(&sctp_af_inet6);
1034}
1035
1036void sctp_v6_pf_exit(void)
1037{
1038        list_del(&sctp_af_inet6.list);
1039}
1040
1041/* Initialize IPv6 support and register with socket layer.  */
1042int sctp_v6_protosw_init(void)
1043{
1044        int rc;
1045
1046        rc = proto_register(&sctpv6_prot, 1);
1047        if (rc)
1048                return rc;
1049
1050        /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */
1051        inet6_register_protosw(&sctpv6_seqpacket_protosw);
1052        inet6_register_protosw(&sctpv6_stream_protosw);
1053
1054        return 0;
1055}
1056
1057void sctp_v6_protosw_exit(void)
1058{
1059        inet6_unregister_protosw(&sctpv6_seqpacket_protosw);
1060        inet6_unregister_protosw(&sctpv6_stream_protosw);
1061        proto_unregister(&sctpv6_prot);
1062}
1063
1064
1065/* Register with inet6 layer. */
1066int sctp_v6_add_protocol(void)
1067{
1068        /* Register notifier for inet6 address additions/deletions. */
1069        register_inet6addr_notifier(&sctp_inet6addr_notifier);
1070
1071        if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0)
1072                return -EAGAIN;
1073
1074        return 0;
1075}
1076
1077/* Unregister with inet6 layer. */
1078void sctp_v6_del_protocol(void)
1079{
1080        inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP);
1081        unregister_inet6addr_notifier(&sctp_inet6addr_notifier);
1082}
1083
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.