net/netfilter/nf_conntrack_h323_main.c

   1 /*
   2  * H.323 connection tracking helper
   3  *
   4  * Copyright (c) 2006 Jing Min Zhao <zhaojingmin@users.sourceforge.net>
   5  *
   6  * This source code is licensed under General Public License version 2.
   7  *
   8  * Based on the 'brute force' H.323 connection tracking module by
   9  * Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
  10  *
  11  * For more information, please see http://nath323.sourceforge.net/
  12  */
  13
  14 #include <linux/module.h>
  15 #include <linux/moduleparam.h>
  16 #include <linux/ctype.h>
  17 #include <linux/inet.h>
  18 #include <linux/in.h>
  19 #include <linux/ip.h>
  20 #include <linux/slab.h>
  21 #include <linux/udp.h>
  22 #include <linux/tcp.h>
  23 #include <linux/skbuff.h>
  24 #include <net/route.h>
  25 #include <net/ip6_route.h>
  26
  27 #include <net/netfilter/nf_conntrack.h>
  28 #include <net/netfilter/nf_conntrack_core.h>
  29 #include <net/netfilter/nf_conntrack_tuple.h>
  30 #include <net/netfilter/nf_conntrack_expect.h>
  31 #include <net/netfilter/nf_conntrack_ecache.h>
  32 #include <net/netfilter/nf_conntrack_helper.h>
  33 #include <net/netfilter/nf_conntrack_zones.h>
  34 #include <linux/netfilter/nf_conntrack_h323.h>
  35
  36 /* Parameters */
  37 static unsigned int default_rrq_ttl __read_mostly = 300;
  38 module_param(default_rrq_ttl, uint, 0600);
  39 MODULE_PARM_DESC(default_rrq_ttl, "use this TTL if it's missing in RRQ");
  40
  41 static int gkrouted_only __read_mostly = 1;
  42 module_param(gkrouted_only, int, 0600);
  43 MODULE_PARM_DESC(gkrouted_only, "only accept calls from gatekeeper");
  44
  45 static int callforward_filter __read_mostly = 1;
  46 module_param(callforward_filter, bool, 0600);
  47 MODULE_PARM_DESC(callforward_filter, "only create call forwarding expectations "
  48                                      "if both endpoints are on different sides "
  49                                      "(determined by routing information)");
  50
  51 /* Hooks for NAT */
  52 int (*set_h245_addr_hook) (struct sk_buff *skb,
  53                            unsigned char **data, int dataoff,
  54                            H245_TransportAddress *taddr,
  55                            union nf_inet_addr *addr, __be16 port)
  56                            __read_mostly;
  57 int (*set_h225_addr_hook) (struct sk_buff *skb,
  58                            unsigned char **data, int dataoff,
  59                            TransportAddress *taddr,
  60                            union nf_inet_addr *addr, __be16 port)
  61                            __read_mostly;
  62 int (*set_sig_addr_hook) (struct sk_buff *skb,
  63                           struct nf_conn *ct,
  64                           enum ip_conntrack_info ctinfo,
  65                           unsigned char **data,
  66                           TransportAddress *taddr, int count) __read_mostly;
  67 int (*set_ras_addr_hook) (struct sk_buff *skb,
  68                           struct nf_conn *ct,
  69                           enum ip_conntrack_info ctinfo,
  70                           unsigned char **data,
  71                           TransportAddress *taddr, int count) __read_mostly;
  72 int (*nat_rtp_rtcp_hook) (struct sk_buff *skb,
  73                           struct nf_conn *ct,
  74                           enum ip_conntrack_info ctinfo,
  75                           unsigned char **data, int dataoff,
  76                           H245_TransportAddress *taddr,
  77                           __be16 port, __be16 rtp_port,
  78                           struct nf_conntrack_expect *rtp_exp,
  79                           struct nf_conntrack_expect *rtcp_exp) __read_mostly;
  80 int (*nat_t120_hook) (struct sk_buff *skb,
  81                       struct nf_conn *ct,
  82                       enum ip_conntrack_info ctinfo,
  83                       unsigned char **data, int dataoff,
  84                       H245_TransportAddress *taddr, __be16 port,
  85                       struct nf_conntrack_expect *exp) __read_mostly;
  86 int (*nat_h245_hook) (struct sk_buff *skb,
  87                       struct nf_conn *ct,
  88                       enum ip_conntrack_info ctinfo,
  89                       unsigned char **data, int dataoff,
  90                       TransportAddress *taddr, __be16 port,
  91                       struct nf_conntrack_expect *exp) __read_mostly;
  92 int (*nat_callforwarding_hook) (struct sk_buff *skb,
  93                                 struct nf_conn *ct,
  94                                 enum ip_conntrack_info ctinfo,
  95                                 unsigned char **data, int dataoff,
  96                                 TransportAddress *taddr, __be16 port,
  97                                 struct nf_conntrack_expect *exp) __read_mostly;
  98 int (*nat_q931_hook) (struct sk_buff *skb,
  99                       struct nf_conn *ct,
 100                       enum ip_conntrack_info ctinfo,
 101                       unsigned char **data, TransportAddress *taddr, int idx,
 102                       __be16 port, struct nf_conntrack_expect *exp)
 103                       __read_mostly;
 104
 105 static DEFINE_SPINLOCK(nf_h323_lock);
 106 static char *h323_buffer;
 107
 108 static struct nf_conntrack_helper nf_conntrack_helper_h245;
 109 static struct nf_conntrack_helper nf_conntrack_helper_q931[];
 110 static struct nf_conntrack_helper nf_conntrack_helper_ras[];
 111
 112 /****************************************************************************/
 113 static int get_tpkt_data(struct sk_buff *skb, unsigned int protoff,
 114                          struct nf_conn *ct, enum ip_conntrack_info ctinfo,
 115                          unsigned char **data, int *datalen, int *dataoff)
 116 {
 117         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
 118         int dir = CTINFO2DIR(ctinfo);
 119         const struct tcphdr *th;
 120         struct tcphdr _tcph;
 121         int tcpdatalen;
 122         int tcpdataoff;
 123         unsigned char *tpkt;
 124         int tpktlen;
 125         int tpktoff;
 126
 127         /* Get TCP header */
 128         th = skb_header_pointer(skb, protoff, sizeof(_tcph), &_tcph);
 129         if (th == NULL)
 130                 return 0;
 131
 132         /* Get TCP data offset */
 133         tcpdataoff = protoff + th->doff * 4;
 134
 135         /* Get TCP data length */
 136         tcpdatalen = skb->len - tcpdataoff;
 137         if (tcpdatalen <= 0)    /* No TCP data */
 138                 goto clear_out;
 139
 140         if (*data == NULL) {    /* first TPKT */
 141                 /* Get first TPKT pointer */
 142                 tpkt = skb_header_pointer(skb, tcpdataoff, tcpdatalen,
 143                                           h323_buffer);
 144                 BUG_ON(tpkt == NULL);
 145
 146                 /* Validate TPKT identifier */
 147                 if (tcpdatalen < 4 || tpkt[0] != 0x03 || tpkt[1] != 0) {
 148                         /* Netmeeting sends TPKT header and data separately */
 149                         if (info->tpkt_len[dir] > 0) {
 150                                 pr_debug("nf_ct_h323: previous packet "
 151                                          "indicated separate TPKT data of %hu "
 152                                          "bytes\n", info->tpkt_len[dir]);
 153                                 if (info->tpkt_len[dir] <= tcpdatalen) {
 154                                         /* Yes, there was a TPKT header
 155                                          * received */
 156                                         *data = tpkt;
 157                                         *datalen = info->tpkt_len[dir];
 158                                         *dataoff = 0;
 159                                         goto out;
 160                                 }
 161
 162                                 /* Fragmented TPKT */
 163                                 pr_debug("nf_ct_h323: fragmented TPKT\n");
 164                                 goto clear_out;
 165                         }
 166
 167                         /* It is not even a TPKT */
 168                         return 0;
 169                 }
 170                 tpktoff = 0;
 171         } else {                /* Next TPKT */
 172                 tpktoff = *dataoff + *datalen;
 173                 tcpdatalen -= tpktoff;
 174                 if (tcpdatalen <= 4)    /* No more TPKT */
 175                         goto clear_out;
 176                 tpkt = *data + *datalen;
 177
 178                 /* Validate TPKT identifier */
 179                 if (tpkt[0] != 0x03 || tpkt[1] != 0)
 180                         goto clear_out;
 181         }
 182
 183         /* Validate TPKT length */
 184         tpktlen = tpkt[2] * 256 + tpkt[3];
 185         if (tpktlen < 4)
 186                 goto clear_out;
 187         if (tpktlen > tcpdatalen) {
 188                 if (tcpdatalen == 4) {  /* Separate TPKT header */
 189                         /* Netmeeting sends TPKT header and data separately */
 190                         pr_debug("nf_ct_h323: separate TPKT header indicates "
 191                                  "there will be TPKT data of %hu bytes\n",
 192                                  tpktlen - 4);
 193                         info->tpkt_len[dir] = tpktlen - 4;
 194                         return 0;
 195                 }
 196
 197                 if (net_ratelimit())
 198                         printk("nf_ct_h323: incomplete TPKT (fragmented?)\n");
 199                 goto clear_out;
 200         }
 201
 202         /* This is the encapsulated data */
 203         *data = tpkt + 4;
 204         *datalen = tpktlen - 4;
 205         *dataoff = tpktoff + 4;
 206
 207       out:
 208         /* Clear TPKT length */
 209         info->tpkt_len[dir] = 0;
 210         return 1;
 211
 212       clear_out:
 213         info->tpkt_len[dir] = 0;
 214         return 0;
 215 }
 216
 217 /****************************************************************************/
 218 static int get_h245_addr(struct nf_conn *ct, const unsigned char *data,
 219                          H245_TransportAddress *taddr,
 220                          union nf_inet_addr *addr, __be16 *port)
 221 {
 222         const unsigned char *p;
 223         int len;
 224
 225         if (taddr->choice != eH245_TransportAddress_unicastAddress)
 226                 return 0;
 227
 228         switch (taddr->unicastAddress.choice) {
 229         case eUnicastAddress_iPAddress:
 230                 if (nf_ct_l3num(ct) != AF_INET)
 231                         return 0;
 232                 p = data + taddr->unicastAddress.iPAddress.network;
 233                 len = 4;
 234                 break;
 235         case eUnicastAddress_iP6Address:
 236                 if (nf_ct_l3num(ct) != AF_INET6)
 237                         return 0;
 238                 p = data + taddr->unicastAddress.iP6Address.network;
 239                 len = 16;
 240                 break;
 241         default:
 242                 return 0;
 243         }
 244
 245         memcpy(addr, p, len);
 246         memset((void *)addr + len, 0, sizeof(*addr) - len);
 247         memcpy(port, p + len, sizeof(__be16));
 248
 249         return 1;
 250 }
 251
 252 /****************************************************************************/
 253 static int expect_rtp_rtcp(struct sk_buff *skb, struct nf_conn *ct,
 254                            enum ip_conntrack_info ctinfo,
 255                            unsigned char **data, int dataoff,
 256                            H245_TransportAddress *taddr)
 257 {
 258         int dir = CTINFO2DIR(ctinfo);
 259         int ret = 0;
 260         __be16 port;
 261         __be16 rtp_port, rtcp_port;
 262         union nf_inet_addr addr;
 263         struct nf_conntrack_expect *rtp_exp;
 264         struct nf_conntrack_expect *rtcp_exp;
 265         typeof(nat_rtp_rtcp_hook) nat_rtp_rtcp;
 266
 267         /* Read RTP or RTCP address */
 268         if (!get_h245_addr(ct, *data, taddr, &addr, &port) ||
 269             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
 270             port == 0)
 271                 return 0;
 272
 273         /* RTP port is even */
 274         port &= htons(~1);
 275         rtp_port = port;
 276         rtcp_port = htons(ntohs(port) + 1);
 277
 278         /* Create expect for RTP */
 279         if ((rtp_exp = nf_ct_expect_alloc(ct)) == NULL)
 280                 return -1;
 281         nf_ct_expect_init(rtp_exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 282                           &ct->tuplehash[!dir].tuple.src.u3,
 283                           &ct->tuplehash[!dir].tuple.dst.u3,
 284                           IPPROTO_UDP, NULL, &rtp_port);
 285
 286         /* Create expect for RTCP */
 287         if ((rtcp_exp = nf_ct_expect_alloc(ct)) == NULL) {
 288                 nf_ct_expect_put(rtp_exp);
 289                 return -1;
 290         }
 291         nf_ct_expect_init(rtcp_exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 292                           &ct->tuplehash[!dir].tuple.src.u3,
 293                           &ct->tuplehash[!dir].tuple.dst.u3,
 294                           IPPROTO_UDP, NULL, &rtcp_port);
 295
 296         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 297                    &ct->tuplehash[!dir].tuple.dst.u3,
 298                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 299                    (nat_rtp_rtcp = rcu_dereference(nat_rtp_rtcp_hook)) &&
 300                    ct->status & IPS_NAT_MASK) {
 301                 /* NAT needed */
 302                 ret = nat_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
 303                                    taddr, port, rtp_port, rtp_exp, rtcp_exp);
 304         } else {                /* Conntrack only */
 305                 if (nf_ct_expect_related(rtp_exp) == 0) {
 306                         if (nf_ct_expect_related(rtcp_exp) == 0) {
 307                                 pr_debug("nf_ct_h323: expect RTP ");
 308                                 nf_ct_dump_tuple(&rtp_exp->tuple);
 309                                 pr_debug("nf_ct_h323: expect RTCP ");
 310                                 nf_ct_dump_tuple(&rtcp_exp->tuple);
 311                         } else {
 312                                 nf_ct_unexpect_related(rtp_exp);
 313                                 ret = -1;
 314                         }
 315                 } else
 316                         ret = -1;
 317         }
 318
 319         nf_ct_expect_put(rtp_exp);
 320         nf_ct_expect_put(rtcp_exp);
 321
 322         return ret;
 323 }
 324
 325 /****************************************************************************/
 326 static int expect_t120(struct sk_buff *skb,
 327                        struct nf_conn *ct,
 328                        enum ip_conntrack_info ctinfo,
 329                        unsigned char **data, int dataoff,
 330                        H245_TransportAddress *taddr)
 331 {
 332         int dir = CTINFO2DIR(ctinfo);
 333         int ret = 0;
 334         __be16 port;
 335         union nf_inet_addr addr;
 336         struct nf_conntrack_expect *exp;
 337         typeof(nat_t120_hook) nat_t120;
 338
 339         /* Read T.120 address */
 340         if (!get_h245_addr(ct, *data, taddr, &addr, &port) ||
 341             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
 342             port == 0)
 343                 return 0;
 344
 345         /* Create expect for T.120 connections */
 346         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
 347                 return -1;
 348         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 349                           &ct->tuplehash[!dir].tuple.src.u3,
 350                           &ct->tuplehash[!dir].tuple.dst.u3,
 351                           IPPROTO_TCP, NULL, &port);
 352         exp->flags = NF_CT_EXPECT_PERMANENT;    /* Accept multiple channels */
 353
 354         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 355                    &ct->tuplehash[!dir].tuple.dst.u3,
 356                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 357             (nat_t120 = rcu_dereference(nat_t120_hook)) &&
 358             ct->status & IPS_NAT_MASK) {
 359                 /* NAT needed */
 360                 ret = nat_t120(skb, ct, ctinfo, data, dataoff, taddr,
 361                                port, exp);
 362         } else {                /* Conntrack only */
 363                 if (nf_ct_expect_related(exp) == 0) {
 364                         pr_debug("nf_ct_h323: expect T.120 ");
 365                         nf_ct_dump_tuple(&exp->tuple);
 366                 } else
 367                         ret = -1;
 368         }
 369
 370         nf_ct_expect_put(exp);
 371
 372         return ret;
 373 }
 374
 375 /****************************************************************************/
 376 static int process_h245_channel(struct sk_buff *skb,
 377                                 struct nf_conn *ct,
 378                                 enum ip_conntrack_info ctinfo,
 379                                 unsigned char **data, int dataoff,
 380                                 H2250LogicalChannelParameters *channel)
 381 {
 382         int ret;
 383
 384         if (channel->options & eH2250LogicalChannelParameters_mediaChannel) {
 385                 /* RTP */
 386                 ret = expect_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
 387                                       &channel->mediaChannel);
 388                 if (ret < 0)
 389                         return -1;
 390         }
 391
 392         if (channel->
 393             options & eH2250LogicalChannelParameters_mediaControlChannel) {
 394                 /* RTCP */
 395                 ret = expect_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
 396                                       &channel->mediaControlChannel);
 397                 if (ret < 0)
 398                         return -1;
 399         }
 400
 401         return 0;
 402 }
 403
 404 /****************************************************************************/
 405 static int process_olc(struct sk_buff *skb, struct nf_conn *ct,
 406                        enum ip_conntrack_info ctinfo,
 407                        unsigned char **data, int dataoff,
 408                        OpenLogicalChannel *olc)
 409 {
 410         int ret;
 411
 412         pr_debug("nf_ct_h323: OpenLogicalChannel\n");
 413
 414         if (olc->forwardLogicalChannelParameters.multiplexParameters.choice ==
 415             eOpenLogicalChannel_forwardLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters)
 416         {
 417                 ret = process_h245_channel(skb, ct, ctinfo, data, dataoff,
 418                                            &olc->
 419                                            forwardLogicalChannelParameters.
 420                                            multiplexParameters.
 421                                            h2250LogicalChannelParameters);
 422                 if (ret < 0)
 423                         return -1;
 424         }
 425
 426         if ((olc->options &
 427              eOpenLogicalChannel_reverseLogicalChannelParameters) &&
 428             (olc->reverseLogicalChannelParameters.options &
 429              eOpenLogicalChannel_reverseLogicalChannelParameters_multiplexParameters)
 430             && (olc->reverseLogicalChannelParameters.multiplexParameters.
 431                 choice ==
 432                 eOpenLogicalChannel_reverseLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters))
 433         {
 434                 ret =
 435                     process_h245_channel(skb, ct, ctinfo, data, dataoff,
 436                                          &olc->
 437                                          reverseLogicalChannelParameters.
 438                                          multiplexParameters.
 439                                          h2250LogicalChannelParameters);
 440                 if (ret < 0)
 441                         return -1;
 442         }
 443
 444         if ((olc->options & eOpenLogicalChannel_separateStack) &&
 445             olc->forwardLogicalChannelParameters.dataType.choice ==
 446             eDataType_data &&
 447             olc->forwardLogicalChannelParameters.dataType.data.application.
 448             choice == eDataApplicationCapability_application_t120 &&
 449             olc->forwardLogicalChannelParameters.dataType.data.application.
 450             t120.choice == eDataProtocolCapability_separateLANStack &&
 451             olc->separateStack.networkAddress.choice ==
 452             eNetworkAccessParameters_networkAddress_localAreaAddress) {
 453                 ret = expect_t120(skb, ct, ctinfo, data, dataoff,
 454                                   &olc->separateStack.networkAddress.
 455                                   localAreaAddress);
 456                 if (ret < 0)
 457                         return -1;
 458         }
 459
 460         return 0;
 461 }
 462
 463 /****************************************************************************/
 464 static int process_olca(struct sk_buff *skb, struct nf_conn *ct,
 465                         enum ip_conntrack_info ctinfo,
 466                         unsigned char **data, int dataoff,
 467                         OpenLogicalChannelAck *olca)
 468 {
 469         H2250LogicalChannelAckParameters *ack;
 470         int ret;
 471
 472         pr_debug("nf_ct_h323: OpenLogicalChannelAck\n");
 473
 474         if ((olca->options &
 475              eOpenLogicalChannelAck_reverseLogicalChannelParameters) &&
 476             (olca->reverseLogicalChannelParameters.options &
 477              eOpenLogicalChannelAck_reverseLogicalChannelParameters_multiplexParameters)
 478             && (olca->reverseLogicalChannelParameters.multiplexParameters.
 479                 choice ==
 480                 eOpenLogicalChannelAck_reverseLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters))
 481         {
 482                 ret = process_h245_channel(skb, ct, ctinfo, data, dataoff,
 483                                            &olca->
 484                                            reverseLogicalChannelParameters.
 485                                            multiplexParameters.
 486                                            h2250LogicalChannelParameters);
 487                 if (ret < 0)
 488                         return -1;
 489         }
 490
 491         if ((olca->options &
 492              eOpenLogicalChannelAck_forwardMultiplexAckParameters) &&
 493             (olca->forwardMultiplexAckParameters.choice ==
 494              eOpenLogicalChannelAck_forwardMultiplexAckParameters_h2250LogicalChannelAckParameters))
 495         {
 496                 ack = &olca->forwardMultiplexAckParameters.
 497                     h2250LogicalChannelAckParameters;
 498                 if (ack->options &
 499                     eH2250LogicalChannelAckParameters_mediaChannel) {
 500                         /* RTP */
 501                         ret = expect_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
 502                                               &ack->mediaChannel);
 503                         if (ret < 0)
 504                                 return -1;
 505                 }
 506
 507                 if (ack->options &
 508                     eH2250LogicalChannelAckParameters_mediaControlChannel) {
 509                         /* RTCP */
 510                         ret = expect_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
 511                                               &ack->mediaControlChannel);
 512                         if (ret < 0)
 513                                 return -1;
 514                 }
 515         }
 516
 517         if ((olca->options & eOpenLogicalChannelAck_separateStack) &&
 518                 olca->separateStack.networkAddress.choice ==
 519                 eNetworkAccessParameters_networkAddress_localAreaAddress) {
 520                 ret = expect_t120(skb, ct, ctinfo, data, dataoff,
 521                                   &olca->separateStack.networkAddress.
 522                                   localAreaAddress);
 523                 if (ret < 0)
 524                         return -1;
 525         }
 526
 527         return 0;
 528 }
 529
 530 /****************************************************************************/
 531 static int process_h245(struct sk_buff *skb, struct nf_conn *ct,
 532                         enum ip_conntrack_info ctinfo,
 533                         unsigned char **data, int dataoff,
 534                         MultimediaSystemControlMessage *mscm)
 535 {
 536         switch (mscm->choice) {
 537         case eMultimediaSystemControlMessage_request:
 538                 if (mscm->request.choice ==
 539                     eRequestMessage_openLogicalChannel) {
 540                         return process_olc(skb, ct, ctinfo, data, dataoff,
 541                                            &mscm->request.openLogicalChannel);
 542                 }
 543                 pr_debug("nf_ct_h323: H.245 Request %d\n",
 544                          mscm->request.choice);
 545                 break;
 546         case eMultimediaSystemControlMessage_response:
 547                 if (mscm->response.choice ==
 548                     eResponseMessage_openLogicalChannelAck) {
 549                         return process_olca(skb, ct, ctinfo, data, dataoff,
 550                                             &mscm->response.
 551                                             openLogicalChannelAck);
 552                 }
 553                 pr_debug("nf_ct_h323: H.245 Response %d\n",
 554                          mscm->response.choice);
 555                 break;
 556         default:
 557                 pr_debug("nf_ct_h323: H.245 signal %d\n", mscm->choice);
 558                 break;
 559         }
 560
 561         return 0;
 562 }
 563
 564 /****************************************************************************/
 565 static int h245_help(struct sk_buff *skb, unsigned int protoff,
 566                      struct nf_conn *ct, enum ip_conntrack_info ctinfo)
 567 {
 568         static MultimediaSystemControlMessage mscm;
 569         unsigned char *data = NULL;
 570         int datalen;
 571         int dataoff;
 572         int ret;
 573
 574         /* Until there's been traffic both ways, don't look in packets. */
 575         if (ctinfo != IP_CT_ESTABLISHED &&
 576             ctinfo != IP_CT_ESTABLISHED + IP_CT_IS_REPLY) {
 577                 return NF_ACCEPT;
 578         }
 579         pr_debug("nf_ct_h245: skblen = %u\n", skb->len);
 580
 581         spin_lock_bh(&nf_h323_lock);
 582
 583         /* Process each TPKT */
 584         while (get_tpkt_data(skb, protoff, ct, ctinfo,
 585                              &data, &datalen, &dataoff)) {
 586                 pr_debug("nf_ct_h245: TPKT len=%d ", datalen);
 587                 nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
 588
 589                 /* Decode H.245 signal */
 590                 ret = DecodeMultimediaSystemControlMessage(data, datalen,
 591                                                            &mscm);
 592                 if (ret < 0) {
 593                         pr_debug("nf_ct_h245: decoding error: %s\n",
 594                                  ret == H323_ERROR_BOUND ?
 595                                  "out of bound" : "out of range");
 596                         /* We don't drop when decoding error */
 597                         break;
 598                 }
 599
 600                 /* Process H.245 signal */
 601                 if (process_h245(skb, ct, ctinfo, &data, dataoff, &mscm) < 0)
 602                         goto drop;
 603         }
 604
 605         spin_unlock_bh(&nf_h323_lock);
 606         return NF_ACCEPT;
 607
 608       drop:
 609         spin_unlock_bh(&nf_h323_lock);
 610         if (net_ratelimit())
 611                 printk("nf_ct_h245: packet dropped\n");
 612         return NF_DROP;
 613 }
 614
 615 /****************************************************************************/
 616 static const struct nf_conntrack_expect_policy h245_exp_policy = {
 617         .max_expected   = H323_RTP_CHANNEL_MAX * 4 + 2 /* T.120 */,
 618         .timeout        = 240,
 619 };
 620
 621 static struct nf_conntrack_helper nf_conntrack_helper_h245 __read_mostly = {
 622         .name                   = "H.245",
 623         .me                     = THIS_MODULE,
 624         .tuple.src.l3num        = AF_UNSPEC,
 625         .tuple.dst.protonum     = IPPROTO_UDP,
 626         .help                   = h245_help,
 627         .expect_policy          = &h245_exp_policy,
 628 };
 629
 630 /****************************************************************************/
 631 int get_h225_addr(struct nf_conn *ct, unsigned char *data,
 632                   TransportAddress *taddr,
 633                   union nf_inet_addr *addr, __be16 *port)
 634 {
 635         const unsigned char *p;
 636         int len;
 637
 638         switch (taddr->choice) {
 639         case eTransportAddress_ipAddress:
 640                 if (nf_ct_l3num(ct) != AF_INET)
 641                         return 0;
 642                 p = data + taddr->ipAddress.ip;
 643                 len = 4;
 644                 break;
 645         case eTransportAddress_ip6Address:
 646                 if (nf_ct_l3num(ct) != AF_INET6)
 647                         return 0;
 648                 p = data + taddr->ip6Address.ip;
 649                 len = 16;
 650                 break;
 651         default:
 652                 return 0;
 653         }
 654
 655         memcpy(addr, p, len);
 656         memset((void *)addr + len, 0, sizeof(*addr) - len);
 657         memcpy(port, p + len, sizeof(__be16));
 658
 659         return 1;
 660 }
 661
 662 /****************************************************************************/
 663 static int expect_h245(struct sk_buff *skb, struct nf_conn *ct,
 664                        enum ip_conntrack_info ctinfo,
 665                        unsigned char **data, int dataoff,
 666                        TransportAddress *taddr)
 667 {
 668         int dir = CTINFO2DIR(ctinfo);
 669         int ret = 0;
 670         __be16 port;
 671         union nf_inet_addr addr;
 672         struct nf_conntrack_expect *exp;
 673         typeof(nat_h245_hook) nat_h245;
 674
 675         /* Read h245Address */
 676         if (!get_h225_addr(ct, *data, taddr, &addr, &port) ||
 677             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
 678             port == 0)
 679                 return 0;
 680
 681         /* Create expect for h245 connection */
 682         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
 683                 return -1;
 684         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 685                           &ct->tuplehash[!dir].tuple.src.u3,
 686                           &ct->tuplehash[!dir].tuple.dst.u3,
 687                           IPPROTO_TCP, NULL, &port);
 688         exp->helper = &nf_conntrack_helper_h245;
 689
 690         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 691                    &ct->tuplehash[!dir].tuple.dst.u3,
 692                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 693             (nat_h245 = rcu_dereference(nat_h245_hook)) &&
 694             ct->status & IPS_NAT_MASK) {
 695                 /* NAT needed */
 696                 ret = nat_h245(skb, ct, ctinfo, data, dataoff, taddr,
 697                                port, exp);
 698         } else {                /* Conntrack only */
 699                 if (nf_ct_expect_related(exp) == 0) {
 700                         pr_debug("nf_ct_q931: expect H.245 ");
 701                         nf_ct_dump_tuple(&exp->tuple);
 702                 } else
 703                         ret = -1;
 704         }
 705
 706         nf_ct_expect_put(exp);
 707
 708         return ret;
 709 }
 710
 711 /* If the calling party is on the same side of the forward-to party,
 712  * we don't need to track the second call */
 713 static int callforward_do_filter(const union nf_inet_addr *src,
 714                                  const union nf_inet_addr *dst,
 715                                  u_int8_t family)
 716 {
 717         const struct nf_afinfo *afinfo;
 718         struct flowi fl1, fl2;
 719         int ret = 0;
 720
 721         /* rcu_read_lock()ed by nf_hook_slow() */
 722         afinfo = nf_get_afinfo(family);
 723         if (!afinfo)
 724                 return 0;
 725
 726         memset(&fl1, 0, sizeof(fl1));
 727         memset(&fl2, 0, sizeof(fl2));
 728
 729         switch (family) {
 730         case AF_INET: {
 731                 struct rtable *rt1, *rt2;
 732
 733                 fl1.fl4_dst = src->ip;
 734                 fl2.fl4_dst = dst->ip;
 735                 if (!afinfo->route((struct dst_entry **)&rt1, &fl1)) {
 736                         if (!afinfo->route((struct dst_entry **)&rt2, &fl2)) {
 737                                 if (rt1->rt_gateway == rt2->rt_gateway &&
 738                                     rt1->u.dst.dev  == rt2->u.dst.dev)
 739                                         ret = 1;
 740                                 dst_release(&rt2->u.dst);
 741                         }
 742                         dst_release(&rt1->u.dst);
 743                 }
 744                 break;
 745         }
 746 #if defined(CONFIG_NF_CONNTRACK_IPV6) || \
 747     defined(CONFIG_NF_CONNTRACK_IPV6_MODULE)
 748         case AF_INET6: {
 749                 struct rt6_info *rt1, *rt2;
 750
 751                 memcpy(&fl1.fl6_dst, src, sizeof(fl1.fl6_dst));
 752                 memcpy(&fl2.fl6_dst, dst, sizeof(fl2.fl6_dst));
 753                 if (!afinfo->route((struct dst_entry **)&rt1, &fl1)) {
 754                         if (!afinfo->route((struct dst_entry **)&rt2, &fl2)) {
 755                                 if (!memcmp(&rt1->rt6i_gateway, &rt2->rt6i_gateway,
 756                                             sizeof(rt1->rt6i_gateway)) &&
 757                                     rt1->u.dst.dev == rt2->u.dst.dev)
 758                                         ret = 1;
 759                                 dst_release(&rt2->u.dst);
 760                         }
 761                         dst_release(&rt1->u.dst);
 762                 }
 763                 break;
 764         }
 765 #endif
 766         }
 767         return ret;
 768
 769 }
 770
 771 /****************************************************************************/
 772 static int expect_callforwarding(struct sk_buff *skb,
 773                                  struct nf_conn *ct,
 774                                  enum ip_conntrack_info ctinfo,
 775                                  unsigned char **data, int dataoff,
 776                                  TransportAddress *taddr)
 777 {
 778         int dir = CTINFO2DIR(ctinfo);
 779         int ret = 0;
 780         __be16 port;
 781         union nf_inet_addr addr;
 782         struct nf_conntrack_expect *exp;
 783         typeof(nat_callforwarding_hook) nat_callforwarding;
 784
 785         /* Read alternativeAddress */
 786         if (!get_h225_addr(ct, *data, taddr, &addr, &port) || port == 0)
 787                 return 0;
 788
 789         /* If the calling party is on the same side of the forward-to party,
 790          * we don't need to track the second call */
 791         if (callforward_filter &&
 792             callforward_do_filter(&addr, &ct->tuplehash[!dir].tuple.src.u3,
 793                                   nf_ct_l3num(ct))) {
 794                 pr_debug("nf_ct_q931: Call Forwarding not tracked\n");
 795                 return 0;
 796         }
 797
 798         /* Create expect for the second call leg */
 799         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
 800                 return -1;
 801         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 802                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
 803                           IPPROTO_TCP, NULL, &port);
 804         exp->helper = nf_conntrack_helper_q931;
 805
 806         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 807                    &ct->tuplehash[!dir].tuple.dst.u3,
 808                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 809             (nat_callforwarding = rcu_dereference(nat_callforwarding_hook)) &&
 810             ct->status & IPS_NAT_MASK) {
 811                 /* Need NAT */
 812                 ret = nat_callforwarding(skb, ct, ctinfo, data, dataoff,
 813                                          taddr, port, exp);
 814         } else {                /* Conntrack only */
 815                 if (nf_ct_expect_related(exp) == 0) {
 816                         pr_debug("nf_ct_q931: expect Call Forwarding ");
 817                         nf_ct_dump_tuple(&exp->tuple);
 818                 } else
 819                         ret = -1;
 820         }
 821
 822         nf_ct_expect_put(exp);
 823
 824         return ret;
 825 }
 826
 827 /****************************************************************************/
 828 static int process_setup(struct sk_buff *skb, struct nf_conn *ct,
 829                          enum ip_conntrack_info ctinfo,
 830                          unsigned char **data, int dataoff,
 831                          Setup_UUIE *setup)
 832 {
 833         int dir = CTINFO2DIR(ctinfo);
 834         int ret;
 835         int i;
 836         __be16 port;
 837         union nf_inet_addr addr;
 838         typeof(set_h225_addr_hook) set_h225_addr;
 839
 840         pr_debug("nf_ct_q931: Setup\n");
 841
 842         if (setup->options & eSetup_UUIE_h245Address) {
 843                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
 844                                   &setup->h245Address);
 845                 if (ret < 0)
 846                         return -1;
 847         }
 848
 849         set_h225_addr = rcu_dereference(set_h225_addr_hook);
 850         if ((setup->options & eSetup_UUIE_destCallSignalAddress) &&
 851             (set_h225_addr) && ct->status & IPS_NAT_MASK &&
 852             get_h225_addr(ct, *data, &setup->destCallSignalAddress,
 853                           &addr, &port) &&
 854             memcmp(&addr, &ct->tuplehash[!dir].tuple.src.u3, sizeof(addr))) {
 855                 pr_debug("nf_ct_q931: set destCallSignalAddress %pI6:%hu->%pI6:%hu\n",
 856                          &addr, ntohs(port), &ct->tuplehash[!dir].tuple.src.u3,
 857                          ntohs(ct->tuplehash[!dir].tuple.src.u.tcp.port));
 858                 ret = set_h225_addr(skb, data, dataoff,
 859                                     &setup->destCallSignalAddress,
 860                                     &ct->tuplehash[!dir].tuple.src.u3,
 861                                     ct->tuplehash[!dir].tuple.src.u.tcp.port);
 862                 if (ret < 0)
 863                         return -1;
 864         }
 865
 866         if ((setup->options & eSetup_UUIE_sourceCallSignalAddress) &&
 867             (set_h225_addr) && ct->status & IPS_NAT_MASK &&
 868             get_h225_addr(ct, *data, &setup->sourceCallSignalAddress,
 869                           &addr, &port) &&
 870             memcmp(&addr, &ct->tuplehash[!dir].tuple.dst.u3, sizeof(addr))) {
 871                 pr_debug("nf_ct_q931: set sourceCallSignalAddress %pI6:%hu->%pI6:%hu\n",
 872                          &addr, ntohs(port), &ct->tuplehash[!dir].tuple.dst.u3,
 873                          ntohs(ct->tuplehash[!dir].tuple.dst.u.tcp.port));
 874                 ret = set_h225_addr(skb, data, dataoff,
 875                                     &setup->sourceCallSignalAddress,
 876                                     &ct->tuplehash[!dir].tuple.dst.u3,
 877                                     ct->tuplehash[!dir].tuple.dst.u.tcp.port);
 878                 if (ret < 0)
 879                         return -1;
 880         }
 881
 882         if (setup->options & eSetup_UUIE_fastStart) {
 883                 for (i = 0; i < setup->fastStart.count; i++) {
 884                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
 885                                           &setup->fastStart.item[i]);
 886                         if (ret < 0)
 887                                 return -1;
 888                 }
 889         }
 890
 891         return 0;
 892 }
 893
 894 /****************************************************************************/
 895 static int process_callproceeding(struct sk_buff *skb,
 896                                   struct nf_conn *ct,
 897                                   enum ip_conntrack_info ctinfo,
 898                                   unsigned char **data, int dataoff,
 899                                   CallProceeding_UUIE *callproc)
 900 {
 901         int ret;
 902         int i;
 903
 904         pr_debug("nf_ct_q931: CallProceeding\n");
 905
 906         if (callproc->options & eCallProceeding_UUIE_h245Address) {
 907                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
 908                                   &callproc->h245Address);
 909                 if (ret < 0)
 910                         return -1;
 911         }
 912
 913         if (callproc->options & eCallProceeding_UUIE_fastStart) {
 914                 for (i = 0; i < callproc->fastStart.count; i++) {
 915                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
 916                                           &callproc->fastStart.item[i]);
 917                         if (ret < 0)
 918                                 return -1;
 919                 }
 920         }
 921
 922         return 0;
 923 }
 924
 925 /****************************************************************************/
 926 static int process_connect(struct sk_buff *skb, struct nf_conn *ct,
 927                            enum ip_conntrack_info ctinfo,
 928                            unsigned char **data, int dataoff,
 929                            Connect_UUIE *connect)
 930 {
 931         int ret;
 932         int i;
 933
 934         pr_debug("nf_ct_q931: Connect\n");
 935
 936         if (connect->options & eConnect_UUIE_h245Address) {
 937                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
 938                                   &connect->h245Address);
 939                 if (ret < 0)
 940                         return -1;
 941         }
 942
 943         if (connect->options & eConnect_UUIE_fastStart) {
 944                 for (i = 0; i < connect->fastStart.count; i++) {
 945                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
 946                                           &connect->fastStart.item[i]);
 947                         if (ret < 0)
 948                                 return -1;
 949                 }
 950         }
 951
 952         return 0;
 953 }
 954
 955 /****************************************************************************/
 956 static int process_alerting(struct sk_buff *skb, struct nf_conn *ct,
 957                             enum ip_conntrack_info ctinfo,
 958                             unsigned char **data, int dataoff,
 959                             Alerting_UUIE *alert)
 960 {
 961         int ret;
 962         int i;
 963
 964         pr_debug("nf_ct_q931: Alerting\n");
 965
 966         if (alert->options & eAlerting_UUIE_h245Address) {
 967                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
 968                                   &alert->h245Address);
 969                 if (ret < 0)
 970                         return -1;
 971         }
 972
 973         if (alert->options & eAlerting_UUIE_fastStart) {
 974                 for (i = 0; i < alert->fastStart.count; i++) {
 975                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
 976                                           &alert->fastStart.item[i]);
 977                         if (ret < 0)
 978                                 return -1;
 979                 }
 980         }
 981
 982         return 0;
 983 }
 984
 985 /****************************************************************************/
 986 static int process_facility(struct sk_buff *skb, struct nf_conn *ct,
 987                             enum ip_conntrack_info ctinfo,
 988                             unsigned char **data, int dataoff,
 989                             Facility_UUIE *facility)
 990 {
 991         int ret;
 992         int i;
 993
 994         pr_debug("nf_ct_q931: Facility\n");
 995
 996         if (facility->reason.choice == eFacilityReason_callForwarded) {
 997                 if (facility->options & eFacility_UUIE_alternativeAddress)
 998                         return expect_callforwarding(skb, ct, ctinfo, data,
 999                                                      dataoff,
1000                                                      &facility->
1001                                                      alternativeAddress);
1002                 return 0;
1003         }
1004
1005         if (facility->options & eFacility_UUIE_h245Address) {
1006                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
1007                                   &facility->h245Address);
1008                 if (ret < 0)
1009                         return -1;
1010         }
1011
1012         if (facility->options & eFacility_UUIE_fastStart) {
1013                 for (i = 0; i < facility->fastStart.count; i++) {
1014                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
1015                                           &facility->fastStart.item[i]);
1016                         if (ret < 0)
1017                                 return -1;
1018                 }
1019         }
1020
1021         return 0;
1022 }
1023
1024 /****************************************************************************/
1025 static int process_progress(struct sk_buff *skb, struct nf_conn *ct,
1026                             enum ip_conntrack_info ctinfo,
1027                             unsigned char **data, int dataoff,
1028                             Progress_UUIE *progress)
1029 {
1030         int ret;
1031         int i;
1032
1033         pr_debug("nf_ct_q931: Progress\n");
1034
1035         if (progress->options & eProgress_UUIE_h245Address) {
1036                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
1037                                   &progress->h245Address);
1038                 if (ret < 0)
1039                         return -1;
1040         }
1041
1042         if (progress->options & eProgress_UUIE_fastStart) {
1043                 for (i = 0; i < progress->fastStart.count; i++) {
1044                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
1045                                           &progress->fastStart.item[i]);
1046                         if (ret < 0)
1047                                 return -1;
1048                 }
1049         }
1050
1051         return 0;
1052 }
1053
1054 /****************************************************************************/
1055 static int process_q931(struct sk_buff *skb, struct nf_conn *ct,
1056                         enum ip_conntrack_info ctinfo,
1057                         unsigned char **data, int dataoff, Q931 *q931)
1058 {
1059         H323_UU_PDU *pdu = &q931->UUIE.h323_uu_pdu;
1060         int i;
1061         int ret = 0;
1062
1063         switch (pdu->h323_message_body.choice) {
1064         case eH323_UU_PDU_h323_message_body_setup:
1065                 ret = process_setup(skb, ct, ctinfo, data, dataoff,
1066                                     &pdu->h323_message_body.setup);
1067                 break;
1068         case eH323_UU_PDU_h323_message_body_callProceeding:
1069                 ret = process_callproceeding(skb, ct, ctinfo, data, dataoff,
1070                                              &pdu->h323_message_body.
1071                                              callProceeding);
1072                 break;
1073         case eH323_UU_PDU_h323_message_body_connect:
1074                 ret = process_connect(skb, ct, ctinfo, data, dataoff,
1075                                       &pdu->h323_message_body.connect);
1076                 break;
1077         case eH323_UU_PDU_h323_message_body_alerting:
1078                 ret = process_alerting(skb, ct, ctinfo, data, dataoff,
1079                                        &pdu->h323_message_body.alerting);
1080                 break;
1081         case eH323_UU_PDU_h323_message_body_facility:
1082                 ret = process_facility(skb, ct, ctinfo, data, dataoff,
1083                                        &pdu->h323_message_body.facility);
1084                 break;
1085         case eH323_UU_PDU_h323_message_body_progress:
1086                 ret = process_progress(skb, ct, ctinfo, data, dataoff,
1087                                        &pdu->h323_message_body.progress);
1088                 break;
1089         default:
1090                 pr_debug("nf_ct_q931: Q.931 signal %d\n",
1091                          pdu->h323_message_body.choice);
1092                 break;
1093         }
1094
1095         if (ret < 0)
1096                 return -1;
1097
1098         if (pdu->options & eH323_UU_PDU_h245Control) {
1099                 for (i = 0; i < pdu->h245Control.count; i++) {
1100                         ret = process_h245(skb, ct, ctinfo, data, dataoff,
1101                                            &pdu->h245Control.item[i]);
1102                         if (ret < 0)
1103                                 return -1;
1104                 }
1105         }
1106
1107         return 0;
1108 }
1109
1110 /****************************************************************************/
1111 static int q931_help(struct sk_buff *skb, unsigned int protoff,
1112                      struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1113 {
1114         static Q931 q931;
1115         unsigned char *data = NULL;
1116         int datalen;
1117         int dataoff;
1118         int ret;
1119
1120         /* Until there's been traffic both ways, don't look in packets. */
1121         if (ctinfo != IP_CT_ESTABLISHED &&
1122             ctinfo != IP_CT_ESTABLISHED + IP_CT_IS_REPLY) {
1123                 return NF_ACCEPT;
1124         }
1125         pr_debug("nf_ct_q931: skblen = %u\n", skb->len);
1126
1127         spin_lock_bh(&nf_h323_lock);
1128
1129         /* Process each TPKT */
1130         while (get_tpkt_data(skb, protoff, ct, ctinfo,
1131                              &data, &datalen, &dataoff)) {
1132                 pr_debug("nf_ct_q931: TPKT len=%d ", datalen);
1133                 nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1134
1135                 /* Decode Q.931 signal */
1136                 ret = DecodeQ931(data, datalen, &q931);
1137                 if (ret < 0) {
1138                         pr_debug("nf_ct_q931: decoding error: %s\n",
1139                                  ret == H323_ERROR_BOUND ?
1140                                  "out of bound" : "out of range");
1141                         /* We don't drop when decoding error */
1142                         break;
1143                 }
1144
1145                 /* Process Q.931 signal */
1146                 if (process_q931(skb, ct, ctinfo, &data, dataoff, &q931) < 0)
1147                         goto drop;
1148         }
1149
1150         spin_unlock_bh(&nf_h323_lock);
1151         return NF_ACCEPT;
1152
1153       drop:
1154         spin_unlock_bh(&nf_h323_lock);
1155         if (net_ratelimit())
1156                 printk("nf_ct_q931: packet dropped\n");
1157         return NF_DROP;
1158 }
1159
1160 /****************************************************************************/
1161 static const struct nf_conntrack_expect_policy q931_exp_policy = {
1162         /* T.120 and H.245 */
1163         .max_expected           = H323_RTP_CHANNEL_MAX * 4 + 4,
1164         .timeout                = 240,
1165 };
1166
1167 static struct nf_conntrack_helper nf_conntrack_helper_q931[] __read_mostly = {
1168         {
1169                 .name                   = "Q.931",
1170                 .me                     = THIS_MODULE,
1171                 .tuple.src.l3num        = AF_INET,
1172                 .tuple.src.u.tcp.port   = cpu_to_be16(Q931_PORT),
1173                 .tuple.dst.protonum     = IPPROTO_TCP,
1174                 .help                   = q931_help,
1175                 .expect_policy          = &q931_exp_policy,
1176         },
1177         {
1178                 .name                   = "Q.931",
1179                 .me                     = THIS_MODULE,
1180                 .tuple.src.l3num        = AF_INET6,
1181                 .tuple.src.u.tcp.port   = cpu_to_be16(Q931_PORT),
1182                 .tuple.dst.protonum     = IPPROTO_TCP,
1183                 .help                   = q931_help,
1184                 .expect_policy          = &q931_exp_policy,
1185         },
1186 };
1187
1188 /****************************************************************************/
1189 static unsigned char *get_udp_data(struct sk_buff *skb, unsigned int protoff,
1190                                    int *datalen)
1191 {
1192         const struct udphdr *uh;
1193         struct udphdr _uh;
1194         int dataoff;
1195
1196         uh = skb_header_pointer(skb, protoff, sizeof(_uh), &_uh);
1197         if (uh == NULL)
1198                 return NULL;
1199         dataoff = protoff + sizeof(_uh);
1200         if (dataoff >= skb->len)
1201                 return NULL;
1202         *datalen = skb->len - dataoff;
1203         return skb_header_pointer(skb, dataoff, *datalen, h323_buffer);
1204 }
1205
1206 /****************************************************************************/
1207 static struct nf_conntrack_expect *find_expect(struct nf_conn *ct,
1208                                                union nf_inet_addr *addr,
1209                                                __be16 port)
1210 {
1211         struct net *net = nf_ct_net(ct);
1212         struct nf_conntrack_expect *exp;
1213         struct nf_conntrack_tuple tuple;
1214
1215         memset(&tuple.src.u3, 0, sizeof(tuple.src.u3));
1216         tuple.src.u.tcp.port = 0;
1217         memcpy(&tuple.dst.u3, addr, sizeof(tuple.dst.u3));
1218         tuple.dst.u.tcp.port = port;
1219         tuple.dst.protonum = IPPROTO_TCP;
1220
1221         exp = __nf_ct_expect_find(net, nf_ct_zone(ct), &tuple);
1222         if (exp && exp->master == ct)
1223                 return exp;
1224         return NULL;
1225 }
1226
1227 /****************************************************************************/
1228 static int set_expect_timeout(struct nf_conntrack_expect *exp,
1229                               unsigned timeout)
1230 {
1231         if (!exp || !del_timer(&exp->timeout))
1232                 return 0;
1233
1234         exp->timeout.expires = jiffies + timeout * HZ;
1235         add_timer(&exp->timeout);
1236
1237         return 1;
1238 }
1239
1240 /****************************************************************************/
1241 static int expect_q931(struct sk_buff *skb, struct nf_conn *ct,
1242                        enum ip_conntrack_info ctinfo,
1243                        unsigned char **data,
1244                        TransportAddress *taddr, int count)
1245 {
1246         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1247         int dir = CTINFO2DIR(ctinfo);
1248         int ret = 0;
1249         int i;
1250         __be16 port;
1251         union nf_inet_addr addr;
1252         struct nf_conntrack_expect *exp;
1253         typeof(nat_q931_hook) nat_q931;
1254
1255         /* Look for the first related address */
1256         for (i = 0; i < count; i++) {
1257                 if (get_h225_addr(ct, *data, &taddr[i], &addr, &port) &&
1258                     memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3,
1259                            sizeof(addr)) == 0 && port != 0)
1260                         break;
1261         }
1262
1263         if (i >= count)         /* Not found */
1264                 return 0;
1265
1266         /* Create expect for Q.931 */
1267         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1268                 return -1;
1269         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1270                           gkrouted_only ? /* only accept calls from GK? */
1271                                 &ct->tuplehash[!dir].tuple.src.u3 : NULL,
1272                           &ct->tuplehash[!dir].tuple.dst.u3,
1273                           IPPROTO_TCP, NULL, &port);
1274         exp->helper = nf_conntrack_helper_q931;
1275         exp->flags = NF_CT_EXPECT_PERMANENT;    /* Accept multiple calls */
1276
1277         nat_q931 = rcu_dereference(nat_q931_hook);
1278         if (nat_q931 && ct->status & IPS_NAT_MASK) {    /* Need NAT */
1279                 ret = nat_q931(skb, ct, ctinfo, data, taddr, i, port, exp);
1280         } else {                /* Conntrack only */
1281                 if (nf_ct_expect_related(exp) == 0) {
1282                         pr_debug("nf_ct_ras: expect Q.931 ");
1283                         nf_ct_dump_tuple(&exp->tuple);
1284
1285                         /* Save port for looking up expect in processing RCF */
1286                         info->sig_port[dir] = port;
1287                 } else
1288                         ret = -1;
1289         }
1290
1291         nf_ct_expect_put(exp);
1292
1293         return ret;
1294 }
1295
1296 /****************************************************************************/
1297 static int process_grq(struct sk_buff *skb, struct nf_conn *ct,
1298                        enum ip_conntrack_info ctinfo,
1299                        unsigned char **data, GatekeeperRequest *grq)
1300 {
1301         typeof(set_ras_addr_hook) set_ras_addr;
1302
1303         pr_debug("nf_ct_ras: GRQ\n");
1304
1305         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1306         if (set_ras_addr && ct->status & IPS_NAT_MASK)  /* NATed */
1307                 return set_ras_addr(skb, ct, ctinfo, data,
1308                                     &grq->rasAddress, 1);
1309         return 0;
1310 }
1311
1312 /****************************************************************************/
1313 static int process_gcf(struct sk_buff *skb, struct nf_conn *ct,
1314                        enum ip_conntrack_info ctinfo,
1315                        unsigned char **data, GatekeeperConfirm *gcf)
1316 {
1317         int dir = CTINFO2DIR(ctinfo);
1318         int ret = 0;
1319         __be16 port;
1320         union nf_inet_addr addr;
1321         struct nf_conntrack_expect *exp;
1322
1323         pr_debug("nf_ct_ras: GCF\n");
1324
1325         if (!get_h225_addr(ct, *data, &gcf->rasAddress, &addr, &port))
1326                 return 0;
1327
1328         /* Registration port is the same as discovery port */
1329         if (!memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1330             port == ct->tuplehash[dir].tuple.src.u.udp.port)
1331                 return 0;
1332
1333         /* Avoid RAS expectation loops. A GCF is never expected. */
1334         if (test_bit(IPS_EXPECTED_BIT, &ct->status))
1335                 return 0;
1336
1337         /* Need new expect */
1338         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1339                 return -1;
1340         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1341                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1342                           IPPROTO_UDP, NULL, &port);
1343         exp->helper = nf_conntrack_helper_ras;
1344
1345         if (nf_ct_expect_related(exp) == 0) {
1346                 pr_debug("nf_ct_ras: expect RAS ");
1347                 nf_ct_dump_tuple(&exp->tuple);
1348         } else
1349                 ret = -1;
1350
1351         nf_ct_expect_put(exp);
1352
1353         return ret;
1354 }
1355
1356 /****************************************************************************/
1357 static int process_rrq(struct sk_buff *skb, struct nf_conn *ct,
1358                        enum ip_conntrack_info ctinfo,
1359                        unsigned char **data, RegistrationRequest *rrq)
1360 {
1361         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1362         int ret;
1363         typeof(set_ras_addr_hook) set_ras_addr;
1364
1365         pr_debug("nf_ct_ras: RRQ\n");
1366
1367         ret = expect_q931(skb, ct, ctinfo, data,
1368                           rrq->callSignalAddress.item,
1369                           rrq->callSignalAddress.count);
1370         if (ret < 0)
1371                 return -1;
1372
1373         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1374         if (set_ras_addr && ct->status & IPS_NAT_MASK) {
1375                 ret = set_ras_addr(skb, ct, ctinfo, data,
1376                                    rrq->rasAddress.item,
1377                                    rrq->rasAddress.count);
1378                 if (ret < 0)
1379                         return -1;
1380         }
1381
1382         if (rrq->options & eRegistrationRequest_timeToLive) {
1383                 pr_debug("nf_ct_ras: RRQ TTL = %u seconds\n", rrq->timeToLive);
1384                 info->timeout = rrq->timeToLive;
1385         } else
1386                 info->timeout = default_rrq_ttl;
1387
1388         return 0;
1389 }
1390
1391 /****************************************************************************/
1392 static int process_rcf(struct sk_buff *skb, struct nf_conn *ct,
1393                        enum ip_conntrack_info ctinfo,
1394                        unsigned char **data, RegistrationConfirm *rcf)
1395 {
1396         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1397         int dir = CTINFO2DIR(ctinfo);
1398         int ret;
1399         struct nf_conntrack_expect *exp;
1400         typeof(set_sig_addr_hook) set_sig_addr;
1401
1402         pr_debug("nf_ct_ras: RCF\n");
1403
1404         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1405         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1406                 ret = set_sig_addr(skb, ct, ctinfo, data,
1407                                         rcf->callSignalAddress.item,
1408                                         rcf->callSignalAddress.count);
1409                 if (ret < 0)
1410                         return -1;
1411         }
1412
1413         if (rcf->options & eRegistrationConfirm_timeToLive) {
1414                 pr_debug("nf_ct_ras: RCF TTL = %u seconds\n", rcf->timeToLive);
1415                 info->timeout = rcf->timeToLive;
1416         }
1417
1418         if (info->timeout > 0) {
1419                 pr_debug("nf_ct_ras: set RAS connection timeout to "
1420                          "%u seconds\n", info->timeout);
1421                 nf_ct_refresh(ct, skb, info->timeout * HZ);
1422
1423                 /* Set expect timeout */
1424                 spin_lock_bh(&nf_conntrack_lock);
1425                 exp = find_expect(ct, &ct->tuplehash[dir].tuple.dst.u3,
1426                                   info->sig_port[!dir]);
1427                 if (exp) {
1428                         pr_debug("nf_ct_ras: set Q.931 expect "
1429                                  "timeout to %u seconds for",
1430                                  info->timeout);
1431                         nf_ct_dump_tuple(&exp->tuple);
1432                         set_expect_timeout(exp, info->timeout);
1433                 }
1434                 spin_unlock_bh(&nf_conntrack_lock);
1435         }
1436
1437         return 0;
1438 }
1439
1440 /****************************************************************************/
1441 static int process_urq(struct sk_buff *skb, struct nf_conn *ct,
1442                        enum ip_conntrack_info ctinfo,
1443                        unsigned char **data, UnregistrationRequest *urq)
1444 {
1445         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1446         int dir = CTINFO2DIR(ctinfo);
1447         int ret;
1448         typeof(set_sig_addr_hook) set_sig_addr;
1449
1450         pr_debug("nf_ct_ras: URQ\n");
1451
1452         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1453         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1454                 ret = set_sig_addr(skb, ct, ctinfo, data,
1455                                    urq->callSignalAddress.item,
1456                                    urq->callSignalAddress.count);
1457                 if (ret < 0)
1458                         return -1;
1459         }
1460
1461         /* Clear old expect */
1462         nf_ct_remove_expectations(ct);
1463         info->sig_port[dir] = 0;
1464         info->sig_port[!dir] = 0;
1465
1466         /* Give it 30 seconds for UCF or URJ */
1467         nf_ct_refresh(ct, skb, 30 * HZ);
1468
1469         return 0;
1470 }
1471
1472 /****************************************************************************/
1473 static int process_arq(struct sk_buff *skb, struct nf_conn *ct,
1474                        enum ip_conntrack_info ctinfo,
1475                        unsigned char **data, AdmissionRequest *arq)
1476 {
1477         const struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1478         int dir = CTINFO2DIR(ctinfo);
1479         __be16 port;
1480         union nf_inet_addr addr;
1481         typeof(set_h225_addr_hook) set_h225_addr;
1482
1483         pr_debug("nf_ct_ras: ARQ\n");
1484
1485         set_h225_addr = rcu_dereference(set_h225_addr_hook);
1486         if ((arq->options & eAdmissionRequest_destCallSignalAddress) &&
1487             get_h225_addr(ct, *data, &arq->destCallSignalAddress,
1488                           &addr, &port) &&
1489             !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1490             port == info->sig_port[dir] &&
1491             set_h225_addr && ct->status & IPS_NAT_MASK) {
1492                 /* Answering ARQ */
1493                 return set_h225_addr(skb, data, 0,
1494                                      &arq->destCallSignalAddress,
1495                                      &ct->tuplehash[!dir].tuple.dst.u3,
1496                                      info->sig_port[!dir]);
1497         }
1498
1499         if ((arq->options & eAdmissionRequest_srcCallSignalAddress) &&
1500             get_h225_addr(ct, *data, &arq->srcCallSignalAddress,
1501                           &addr, &port) &&
1502             !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1503             set_h225_addr && ct->status & IPS_NAT_MASK) {
1504                 /* Calling ARQ */
1505                 return set_h225_addr(skb, data, 0,
1506                                      &arq->srcCallSignalAddress,
1507                                      &ct->tuplehash[!dir].tuple.dst.u3,
1508                                      port);
1509         }
1510
1511         return 0;
1512 }
1513
1514 /****************************************************************************/
1515 static int process_acf(struct sk_buff *skb, struct nf_conn *ct,
1516                        enum ip_conntrack_info ctinfo,
1517                        unsigned char **data, AdmissionConfirm *acf)
1518 {
1519         int dir = CTINFO2DIR(ctinfo);
1520         int ret = 0;
1521         __be16 port;
1522         union nf_inet_addr addr;
1523         struct nf_conntrack_expect *exp;
1524         typeof(set_sig_addr_hook) set_sig_addr;
1525
1526         pr_debug("nf_ct_ras: ACF\n");
1527
1528         if (!get_h225_addr(ct, *data, &acf->destCallSignalAddress,
1529                            &addr, &port))
1530                 return 0;
1531
1532         if (!memcmp(&addr, &ct->tuplehash[dir].tuple.dst.u3, sizeof(addr))) {
1533                 /* Answering ACF */
1534                 set_sig_addr = rcu_dereference(set_sig_addr_hook);
1535                 if (set_sig_addr && ct->status & IPS_NAT_MASK)
1536                         return set_sig_addr(skb, ct, ctinfo, data,
1537                                             &acf->destCallSignalAddress, 1);
1538                 return 0;
1539         }
1540
1541         /* Need new expect */
1542         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1543                 return -1;
1544         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1545                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1546                           IPPROTO_TCP, NULL, &port);
1547         exp->flags = NF_CT_EXPECT_PERMANENT;
1548         exp->helper = nf_conntrack_helper_q931;
1549
1550         if (nf_ct_expect_related(exp) == 0) {
1551                 pr_debug("nf_ct_ras: expect Q.931 ");
1552                 nf_ct_dump_tuple(&exp->tuple);
1553         } else
1554                 ret = -1;
1555
1556         nf_ct_expect_put(exp);
1557
1558         return ret;
1559 }
1560
1561 /****************************************************************************/
1562 static int process_lrq(struct sk_buff *skb, struct nf_conn *ct,
1563                        enum ip_conntrack_info ctinfo,
1564                        unsigned char **data, LocationRequest *lrq)
1565 {
1566         typeof(set_ras_addr_hook) set_ras_addr;
1567
1568         pr_debug("nf_ct_ras: LRQ\n");
1569
1570         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1571         if (set_ras_addr && ct->status & IPS_NAT_MASK)
1572                 return set_ras_addr(skb, ct, ctinfo, data,
1573                                     &lrq->replyAddress, 1);
1574         return 0;
1575 }
1576
1577 /****************************************************************************/
1578 static int process_lcf(struct sk_buff *skb, struct nf_conn *ct,
1579                        enum ip_conntrack_info ctinfo,
1580                        unsigned char **data, LocationConfirm *lcf)
1581 {
1582         int dir = CTINFO2DIR(ctinfo);
1583         int ret = 0;
1584         __be16 port;
1585         union nf_inet_addr addr;
1586         struct nf_conntrack_expect *exp;
1587
1588         pr_debug("nf_ct_ras: LCF\n");
1589
1590         if (!get_h225_addr(ct, *data, &lcf->callSignalAddress,
1591                            &addr, &port))
1592                 return 0;
1593
1594         /* Need new expect for call signal */
1595         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1596                 return -1;
1597         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1598                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1599                           IPPROTO_TCP, NULL, &port);
1600         exp->flags = NF_CT_EXPECT_PERMANENT;
1601         exp->helper = nf_conntrack_helper_q931;
1602
1603         if (nf_ct_expect_related(exp) == 0) {
1604                 pr_debug("nf_ct_ras: expect Q.931 ");
1605                 nf_ct_dump_tuple(&exp->tuple);
1606         } else
1607                 ret = -1;
1608
1609         nf_ct_expect_put(exp);
1610
1611         /* Ignore rasAddress */
1612
1613         return ret;
1614 }
1615
1616 /****************************************************************************/
1617 static int process_irr(struct sk_buff *skb, struct nf_conn *ct,
1618                        enum ip_conntrack_info ctinfo,
1619                        unsigned char **data, InfoRequestResponse *irr)
1620 {
1621         int ret;
1622         typeof(set_ras_addr_hook) set_ras_addr;
1623         typeof(set_sig_addr_hook) set_sig_addr;
1624
1625         pr_debug("nf_ct_ras: IRR\n");
1626
1627         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1628         if (set_ras_addr && ct->status & IPS_NAT_MASK) {
1629                 ret = set_ras_addr(skb, ct, ctinfo, data,
1630                                    &irr->rasAddress, 1);
1631                 if (ret < 0)
1632                         return -1;
1633         }
1634
1635         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1636         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1637                 ret = set_sig_addr(skb, ct, ctinfo, data,
1638                                         irr->callSignalAddress.item,
1639                                         irr->callSignalAddress.count);
1640                 if (ret < 0)
1641                         return -1;
1642         }
1643
1644         return 0;
1645 }
1646
1647 /****************************************************************************/
1648 static int process_ras(struct sk_buff *skb, struct nf_conn *ct,
1649                        enum ip_conntrack_info ctinfo,
1650                        unsigned char **data, RasMessage *ras)
1651 {
1652         switch (ras->choice) {
1653         case eRasMessage_gatekeeperRequest:
1654                 return process_grq(skb, ct, ctinfo, data,
1655                                    &ras->gatekeeperRequest);
1656         case eRasMessage_gatekeeperConfirm:
1657                 return process_gcf(skb, ct, ctinfo, data,
1658                                    &ras->gatekeeperConfirm);
1659         case eRasMessage_registrationRequest:
1660                 return process_rrq(skb, ct, ctinfo, data,
1661                                    &ras->registrationRequest);
1662         case eRasMessage_registrationConfirm:
1663                 return process_rcf(skb, ct, ctinfo, data,
1664                                    &ras->registrationConfirm);
1665         case eRasMessage_unregistrationRequest:
1666                 return process_urq(skb, ct, ctinfo, data,
1667                                    &ras->unregistrationRequest);
1668         case eRasMessage_admissionRequest:
1669                 return process_arq(skb, ct, ctinfo, data,
1670                                    &ras->admissionRequest);
1671         case eRasMessage_admissionConfirm:
1672                 return process_acf(skb, ct, ctinfo, data,
1673                                    &ras->admissionConfirm);
1674         case eRasMessage_locationRequest:
1675                 return process_lrq(skb, ct, ctinfo, data,
1676                                    &ras->locationRequest);
1677         case eRasMessage_locationConfirm:
1678                 return process_lcf(skb, ct, ctinfo, data,
1679                                    &ras->locationConfirm);
1680         case eRasMessage_infoRequestResponse:
1681                 return process_irr(skb, ct, ctinfo, data,
1682                                    &ras->infoRequestResponse);
1683         default:
1684                 pr_debug("nf_ct_ras: RAS message %d\n", ras->choice);
1685                 break;
1686         }
1687
1688         return 0;
1689 }
1690
1691 /****************************************************************************/
1692 static int ras_help(struct sk_buff *skb, unsigned int protoff,
1693                     struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1694 {
1695         static RasMessage ras;
1696         unsigned char *data;
1697         int datalen = 0;
1698         int ret;
1699
1700         pr_debug("nf_ct_ras: skblen = %u\n", skb->len);
1701
1702         spin_lock_bh(&nf_h323_lock);
1703
1704         /* Get UDP data */
1705         data = get_udp_data(skb, protoff, &datalen);
1706         if (data == NULL)
1707                 goto accept;
1708         pr_debug("nf_ct_ras: RAS message len=%d ", datalen);
1709         nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1710
1711         /* Decode RAS message */
1712         ret = DecodeRasMessage(data, datalen, &ras);
1713         if (ret < 0) {
1714                 pr_debug("nf_ct_ras: decoding error: %s\n",
1715                          ret == H323_ERROR_BOUND ?
1716                          "out of bound" : "out of range");
1717                 goto accept;
1718         }
1719
1720         /* Process RAS message */
1721         if (process_ras(skb, ct, ctinfo, &data, &ras) < 0)
1722                 goto drop;
1723
1724       accept:
1725         spin_unlock_bh(&nf_h323_lock);
1726         return NF_ACCEPT;
1727
1728       drop:
1729         spin_unlock_bh(&nf_h323_lock);
1730         if (net_ratelimit())
1731                 printk("nf_ct_ras: packet dropped\n");
1732         return NF_DROP;
1733 }
1734
1735 /****************************************************************************/
1736 static const struct nf_conntrack_expect_policy ras_exp_policy = {
1737         .max_expected           = 32,
1738         .timeout                = 240,
1739 };
1740
1741 static struct nf_conntrack_helper nf_conntrack_helper_ras[] __read_mostly = {
1742         {
1743                 .name                   = "RAS",
1744                 .me                     = THIS_MODULE,
1745                 .tuple.src.l3num        = AF_INET,
1746                 .tuple.src.u.udp.port   = cpu_to_be16(RAS_PORT),
1747                 .tuple.dst.protonum     = IPPROTO_UDP,
1748                 .help                   = ras_help,
1749                 .expect_policy          = &ras_exp_policy,
1750         },
1751         {
1752                 .name                   = "RAS",
1753                 .me                     = THIS_MODULE,
1754                 .tuple.src.l3num        = AF_INET6,
1755                 .tuple.src.u.udp.port   = cpu_to_be16(RAS_PORT),
1756                 .tuple.dst.protonum     = IPPROTO_UDP,
1757                 .help                   = ras_help,
1758                 .expect_policy          = &ras_exp_policy,
1759         },
1760 };
1761
1762 /****************************************************************************/
1763 static void __exit nf_conntrack_h323_fini(void)
1764 {
1765         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[1]);
1766         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1767         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1768         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1769         nf_conntrack_helper_unregister(&nf_conntrack_helper_h245);
1770         kfree(h323_buffer);
1771         pr_debug("nf_ct_h323: fini\n");
1772 }
1773
1774 /****************************************************************************/
1775 static int __init nf_conntrack_h323_init(void)
1776 {
1777         int ret;
1778
1779         h323_buffer = kmalloc(65536, GFP_KERNEL);
1780         if (!h323_buffer)
1781                 return -ENOMEM;
1782         ret = nf_conntrack_helper_register(&nf_conntrack_helper_h245);
1783         if (ret < 0)
1784                 goto err1;
1785         ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[0]);
1786         if (ret < 0)
1787                 goto err2;
1788         ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[1]);
1789         if (ret < 0)
1790                 goto err3;
1791         ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[0]);
1792         if (ret < 0)
1793                 goto err4;
1794         ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[1]);
1795         if (ret < 0)
1796                 goto err5;
1797         pr_debug("nf_ct_h323: init success\n");
1798         return 0;
1799
1800 err5:
1801         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1802 err4:
1803         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1804 err3:
1805         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1806 err2:
1807         nf_conntrack_helper_unregister(&nf_conntrack_helper_h245);
1808 err1:
1809         kfree(h323_buffer);
1810         return ret;
1811 }
1812
1813 /****************************************************************************/
1814 module_init(nf_conntrack_h323_init);
1815 module_exit(nf_conntrack_h323_fini);
1816
1817 EXPORT_SYMBOL_GPL(get_h225_addr);
1818 EXPORT_SYMBOL_GPL(set_h245_addr_hook);
1819 EXPORT_SYMBOL_GPL(set_h225_addr_hook);
1820 EXPORT_SYMBOL_GPL(set_sig_addr_hook);
1821 EXPORT_SYMBOL_GPL(set_ras_addr_hook);
1822 EXPORT_SYMBOL_GPL(nat_rtp_rtcp_hook);
1823 EXPORT_SYMBOL_GPL(nat_t120_hook);
1824 EXPORT_SYMBOL_GPL(nat_h245_hook);
1825 EXPORT_SYMBOL_GPL(nat_callforwarding_hook);
1826 EXPORT_SYMBOL_GPL(nat_q931_hook);
1827
1828 MODULE_AUTHOR("Jing Min Zhao <zhaojingmin@users.sourceforge.net>");
1829 MODULE_DESCRIPTION("H.323 connection tracking helper");
1830 MODULE_LICENSE("GPL");
1831 MODULE_ALIAS("ip_conntrack_h323");
1832 MODULE_ALIAS_NFCT_HELPER("h323");