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/udp.h>
  21 #include <linux/tcp.h>
  22 #include <linux/skbuff.h>
  23 #include <net/route.h>
  24 #include <net/ip6_route.h>
  25
  26 #include <net/netfilter/nf_conntrack.h>
  27 #include <net/netfilter/nf_conntrack_core.h>
  28 #include <net/netfilter/nf_conntrack_tuple.h>
  29 #include <net/netfilter/nf_conntrack_expect.h>
  30 #include <net/netfilter/nf_conntrack_ecache.h>
  31 #include <net/netfilter/nf_conntrack_helper.h>
  32 #include <linux/netfilter/nf_conntrack_h323.h>
  33
  34 /* Parameters */
  35 static unsigned int default_rrq_ttl __read_mostly = 300;
  36 module_param(default_rrq_ttl, uint, 0600);
  37 MODULE_PARM_DESC(default_rrq_ttl, "use this TTL if it's missing in RRQ");
  38
  39 static int gkrouted_only __read_mostly = 1;
  40 module_param(gkrouted_only, int, 0600);
  41 MODULE_PARM_DESC(gkrouted_only, "only accept calls from gatekeeper");
  42
  43 static int callforward_filter __read_mostly = 1;
  44 module_param(callforward_filter, bool, 0600);
  45 MODULE_PARM_DESC(callforward_filter, "only create call forwarding expectations "
  46                                      "if both endpoints are on different sides "
  47                                      "(determined by routing information)");
  48
  49 /* Hooks for NAT */
  50 int (*set_h245_addr_hook) (struct sk_buff *skb,
  51                            unsigned char **data, int dataoff,
  52                            H245_TransportAddress *taddr,
  53                            union nf_inet_addr *addr, __be16 port)
  54                            __read_mostly;
  55 int (*set_h225_addr_hook) (struct sk_buff *skb,
  56                            unsigned char **data, int dataoff,
  57                            TransportAddress *taddr,
  58                            union nf_inet_addr *addr, __be16 port)
  59                            __read_mostly;
  60 int (*set_sig_addr_hook) (struct sk_buff *skb,
  61                           struct nf_conn *ct,
  62                           enum ip_conntrack_info ctinfo,
  63                           unsigned char **data,
  64                           TransportAddress *taddr, int count) __read_mostly;
  65 int (*set_ras_addr_hook) (struct sk_buff *skb,
  66                           struct nf_conn *ct,
  67                           enum ip_conntrack_info ctinfo,
  68                           unsigned char **data,
  69                           TransportAddress *taddr, int count) __read_mostly;
  70 int (*nat_rtp_rtcp_hook) (struct sk_buff *skb,
  71                           struct nf_conn *ct,
  72                           enum ip_conntrack_info ctinfo,
  73                           unsigned char **data, int dataoff,
  74                           H245_TransportAddress *taddr,
  75                           __be16 port, __be16 rtp_port,
  76                           struct nf_conntrack_expect *rtp_exp,
  77                           struct nf_conntrack_expect *rtcp_exp) __read_mostly;
  78 int (*nat_t120_hook) (struct sk_buff *skb,
  79                       struct nf_conn *ct,
  80                       enum ip_conntrack_info ctinfo,
  81                       unsigned char **data, int dataoff,
  82                       H245_TransportAddress *taddr, __be16 port,
  83                       struct nf_conntrack_expect *exp) __read_mostly;
  84 int (*nat_h245_hook) (struct sk_buff *skb,
  85                       struct nf_conn *ct,
  86                       enum ip_conntrack_info ctinfo,
  87                       unsigned char **data, int dataoff,
  88                       TransportAddress *taddr, __be16 port,
  89                       struct nf_conntrack_expect *exp) __read_mostly;
  90 int (*nat_callforwarding_hook) (struct sk_buff *skb,
  91                                 struct nf_conn *ct,
  92                                 enum ip_conntrack_info ctinfo,
  93                                 unsigned char **data, int dataoff,
  94                                 TransportAddress *taddr, __be16 port,
  95                                 struct nf_conntrack_expect *exp) __read_mostly;
  96 int (*nat_q931_hook) (struct sk_buff *skb,
  97                       struct nf_conn *ct,
  98                       enum ip_conntrack_info ctinfo,
  99                       unsigned char **data, TransportAddress *taddr, int idx,
 100                       __be16 port, struct nf_conntrack_expect *exp)
 101                       __read_mostly;
 102
 103 static DEFINE_SPINLOCK(nf_h323_lock);
 104 static char *h323_buffer;
 105
 106 static struct nf_conntrack_helper nf_conntrack_helper_h245;
 107 static struct nf_conntrack_helper nf_conntrack_helper_q931[];
 108 static struct nf_conntrack_helper nf_conntrack_helper_ras[];
 109
 110 /****************************************************************************/
 111 static int get_tpkt_data(struct sk_buff *skb, unsigned int protoff,
 112                          struct nf_conn *ct, enum ip_conntrack_info ctinfo,
 113                          unsigned char **data, int *datalen, int *dataoff)
 114 {
 115         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
 116         int dir = CTINFO2DIR(ctinfo);
 117         const struct tcphdr *th;
 118         struct tcphdr _tcph;
 119         int tcpdatalen;
 120         int tcpdataoff;
 121         unsigned char *tpkt;
 122         int tpktlen;
 123         int tpktoff;
 124
 125         /* Get TCP header */
 126         th = skb_header_pointer(skb, protoff, sizeof(_tcph), &_tcph);
 127         if (th == NULL)
 128                 return 0;
 129
 130         /* Get TCP data offset */
 131         tcpdataoff = protoff + th->doff * 4;
 132
 133         /* Get TCP data length */
 134         tcpdatalen = skb->len - tcpdataoff;
 135         if (tcpdatalen <= 0)    /* No TCP data */
 136                 goto clear_out;
 137
 138         if (*data == NULL) {    /* first TPKT */
 139                 /* Get first TPKT pointer */
 140                 tpkt = skb_header_pointer(skb, tcpdataoff, tcpdatalen,
 141                                           h323_buffer);
 142                 BUG_ON(tpkt == NULL);
 143
 144                 /* Validate TPKT identifier */
 145                 if (tcpdatalen < 4 || tpkt[0] != 0x03 || tpkt[1] != 0) {
 146                         /* Netmeeting sends TPKT header and data separately */
 147                         if (info->tpkt_len[dir] > 0) {
 148                                 pr_debug("nf_ct_h323: previous packet "
 149                                          "indicated separate TPKT data of %hu "
 150                                          "bytes\n", info->tpkt_len[dir]);
 151                                 if (info->tpkt_len[dir] <= tcpdatalen) {
 152                                         /* Yes, there was a TPKT header
 153                                          * received */
 154                                         *data = tpkt;
 155                                         *datalen = info->tpkt_len[dir];
 156                                         *dataoff = 0;
 157                                         goto out;
 158                                 }
 159
 160                                 /* Fragmented TPKT */
 161                                 pr_debug("nf_ct_h323: fragmented TPKT\n");
 162                                 goto clear_out;
 163                         }
 164
 165                         /* It is not even a TPKT */
 166                         return 0;
 167                 }
 168                 tpktoff = 0;
 169         } else {                /* Next TPKT */
 170                 tpktoff = *dataoff + *datalen;
 171                 tcpdatalen -= tpktoff;
 172                 if (tcpdatalen <= 4)    /* No more TPKT */
 173                         goto clear_out;
 174                 tpkt = *data + *datalen;
 175
 176                 /* Validate TPKT identifier */
 177                 if (tpkt[0] != 0x03 || tpkt[1] != 0)
 178                         goto clear_out;
 179         }
 180
 181         /* Validate TPKT length */
 182         tpktlen = tpkt[2] * 256 + tpkt[3];
 183         if (tpktlen < 4)
 184                 goto clear_out;
 185         if (tpktlen > tcpdatalen) {
 186                 if (tcpdatalen == 4) {  /* Separate TPKT header */
 187                         /* Netmeeting sends TPKT header and data separately */
 188                         pr_debug("nf_ct_h323: separate TPKT header indicates "
 189                                  "there will be TPKT data of %hu bytes\n",
 190                                  tpktlen - 4);
 191                         info->tpkt_len[dir] = tpktlen - 4;
 192                         return 0;
 193                 }
 194
 195                 if (net_ratelimit())
 196                         printk("nf_ct_h323: incomplete TPKT (fragmented?)\n");
 197                 goto clear_out;
 198         }
 199
 200         /* This is the encapsulated data */
 201         *data = tpkt + 4;
 202         *datalen = tpktlen - 4;
 203         *dataoff = tpktoff + 4;
 204
 205       out:
 206         /* Clear TPKT length */
 207         info->tpkt_len[dir] = 0;
 208         return 1;
 209
 210       clear_out:
 211         info->tpkt_len[dir] = 0;
 212         return 0;
 213 }
 214
 215 /****************************************************************************/
 216 static int get_h245_addr(struct nf_conn *ct, const unsigned char *data,
 217                          H245_TransportAddress *taddr,
 218                          union nf_inet_addr *addr, __be16 *port)
 219 {
 220         const unsigned char *p;
 221         int family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 222         int len;
 223
 224         if (taddr->choice != eH245_TransportAddress_unicastAddress)
 225                 return 0;
 226
 227         switch (taddr->unicastAddress.choice) {
 228         case eUnicastAddress_iPAddress:
 229                 if (family != AF_INET)
 230                         return 0;
 231                 p = data + taddr->unicastAddress.iPAddress.network;
 232                 len = 4;
 233                 break;
 234         case eUnicastAddress_iP6Address:
 235                 if (family != AF_INET6)
 236                         return 0;
 237                 p = data + taddr->unicastAddress.iP6Address.network;
 238                 len = 16;
 239                 break;
 240         default:
 241                 return 0;
 242         }
 243
 244         memcpy(addr, p, len);
 245         memset((void *)addr + len, 0, sizeof(*addr) - len);
 246         memcpy(port, p + len, sizeof(__be16));
 247
 248         return 1;
 249 }
 250
 251 /****************************************************************************/
 252 static int expect_rtp_rtcp(struct sk_buff *skb, struct nf_conn *ct,
 253                            enum ip_conntrack_info ctinfo,
 254                            unsigned char **data, int dataoff,
 255                            H245_TransportAddress *taddr)
 256 {
 257         int dir = CTINFO2DIR(ctinfo);
 258         int ret = 0;
 259         __be16 port;
 260         __be16 rtp_port, rtcp_port;
 261         union nf_inet_addr addr;
 262         struct nf_conntrack_expect *rtp_exp;
 263         struct nf_conntrack_expect *rtcp_exp;
 264         typeof(nat_rtp_rtcp_hook) nat_rtp_rtcp;
 265
 266         /* Read RTP or RTCP address */
 267         if (!get_h245_addr(ct, *data, taddr, &addr, &port) ||
 268             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
 269             port == 0)
 270                 return 0;
 271
 272         /* RTP port is even */
 273         port &= htons(~1);
 274         rtp_port = port;
 275         rtcp_port = htons(ntohs(port) + 1);
 276
 277         /* Create expect for RTP */
 278         if ((rtp_exp = nf_ct_expect_alloc(ct)) == NULL)
 279                 return -1;
 280         nf_ct_expect_init(rtp_exp, NF_CT_EXPECT_CLASS_DEFAULT,
 281                           ct->tuplehash[!dir].tuple.src.l3num,
 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,
 292                           ct->tuplehash[!dir].tuple.src.l3num,
 293                           &ct->tuplehash[!dir].tuple.src.u3,
 294                           &ct->tuplehash[!dir].tuple.dst.u3,
 295                           IPPROTO_UDP, NULL, &rtcp_port);
 296
 297         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 298                    &ct->tuplehash[!dir].tuple.dst.u3,
 299                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 300                    (nat_rtp_rtcp = rcu_dereference(nat_rtp_rtcp_hook)) &&
 301                    ct->status & IPS_NAT_MASK) {
 302                 /* NAT needed */
 303                 ret = nat_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
 304                                    taddr, port, rtp_port, rtp_exp, rtcp_exp);
 305         } else {                /* Conntrack only */
 306                 if (nf_ct_expect_related(rtp_exp) == 0) {
 307                         if (nf_ct_expect_related(rtcp_exp) == 0) {
 308                                 pr_debug("nf_ct_h323: expect RTP ");
 309                                 NF_CT_DUMP_TUPLE(&rtp_exp->tuple);
 310                                 pr_debug("nf_ct_h323: expect RTCP ");
 311                                 NF_CT_DUMP_TUPLE(&rtcp_exp->tuple);
 312                         } else {
 313                                 nf_ct_unexpect_related(rtp_exp);
 314                                 ret = -1;
 315                         }
 316                 } else
 317                         ret = -1;
 318         }
 319
 320         nf_ct_expect_put(rtp_exp);
 321         nf_ct_expect_put(rtcp_exp);
 322
 323         return ret;
 324 }
 325
 326 /****************************************************************************/
 327 static int expect_t120(struct sk_buff *skb,
 328                        struct nf_conn *ct,
 329                        enum ip_conntrack_info ctinfo,
 330                        unsigned char **data, int dataoff,
 331                        H245_TransportAddress *taddr)
 332 {
 333         int dir = CTINFO2DIR(ctinfo);
 334         int ret = 0;
 335         __be16 port;
 336         union nf_inet_addr addr;
 337         struct nf_conntrack_expect *exp;
 338         typeof(nat_t120_hook) nat_t120;
 339
 340         /* Read T.120 address */
 341         if (!get_h245_addr(ct, *data, taddr, &addr, &port) ||
 342             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
 343             port == 0)
 344                 return 0;
 345
 346         /* Create expect for T.120 connections */
 347         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
 348                 return -1;
 349         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT,
 350                           ct->tuplehash[!dir].tuple.src.l3num,
 351                           &ct->tuplehash[!dir].tuple.src.u3,
 352                           &ct->tuplehash[!dir].tuple.dst.u3,
 353                           IPPROTO_TCP, NULL, &port);
 354         exp->flags = NF_CT_EXPECT_PERMANENT;    /* Accept multiple channels */
 355
 356         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 357                    &ct->tuplehash[!dir].tuple.dst.u3,
 358                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 359             (nat_t120 = rcu_dereference(nat_t120_hook)) &&
 360             ct->status & IPS_NAT_MASK) {
 361                 /* NAT needed */
 362                 ret = nat_t120(skb, ct, ctinfo, data, dataoff, taddr,
 363                                port, exp);
 364         } else {                /* Conntrack only */
 365                 if (nf_ct_expect_related(exp) == 0) {
 366                         pr_debug("nf_ct_h323: expect T.120 ");
 367                         NF_CT_DUMP_TUPLE(&exp->tuple);
 368                 } else
 369                         ret = -1;
 370         }
 371
 372         nf_ct_expect_put(exp);
 373
 374         return ret;
 375 }
 376
 377 /****************************************************************************/
 378 static int process_h245_channel(struct sk_buff *skb,
 379                                 struct nf_conn *ct,
 380                                 enum ip_conntrack_info ctinfo,
 381                                 unsigned char **data, int dataoff,
 382                                 H2250LogicalChannelParameters *channel)
 383 {
 384         int ret;
 385
 386         if (channel->options & eH2250LogicalChannelParameters_mediaChannel) {
 387                 /* RTP */
 388                 ret = expect_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
 389                                       &channel->mediaChannel);
 390                 if (ret < 0)
 391                         return -1;
 392         }
 393
 394         if (channel->
 395             options & eH2250LogicalChannelParameters_mediaControlChannel) {
 396                 /* RTCP */
 397                 ret = expect_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
 398                                       &channel->mediaControlChannel);
 399                 if (ret < 0)
 400                         return -1;
 401         }
 402
 403         return 0;
 404 }
 405
 406 /****************************************************************************/
 407 static int process_olc(struct sk_buff *skb, struct nf_conn *ct,
 408                        enum ip_conntrack_info ctinfo,
 409                        unsigned char **data, int dataoff,
 410                        OpenLogicalChannel *olc)
 411 {
 412         int ret;
 413
 414         pr_debug("nf_ct_h323: OpenLogicalChannel\n");
 415
 416         if (olc->forwardLogicalChannelParameters.multiplexParameters.choice ==
 417             eOpenLogicalChannel_forwardLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters)
 418         {
 419                 ret = process_h245_channel(skb, ct, ctinfo, data, dataoff,
 420                                            &olc->
 421                                            forwardLogicalChannelParameters.
 422                                            multiplexParameters.
 423                                            h2250LogicalChannelParameters);
 424                 if (ret < 0)
 425                         return -1;
 426         }
 427
 428         if ((olc->options &
 429              eOpenLogicalChannel_reverseLogicalChannelParameters) &&
 430             (olc->reverseLogicalChannelParameters.options &
 431              eOpenLogicalChannel_reverseLogicalChannelParameters_multiplexParameters)
 432             && (olc->reverseLogicalChannelParameters.multiplexParameters.
 433                 choice ==
 434                 eOpenLogicalChannel_reverseLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters))
 435         {
 436                 ret =
 437                     process_h245_channel(skb, ct, ctinfo, data, dataoff,
 438                                          &olc->
 439                                          reverseLogicalChannelParameters.
 440                                          multiplexParameters.
 441                                          h2250LogicalChannelParameters);
 442                 if (ret < 0)
 443                         return -1;
 444         }
 445
 446         if ((olc->options & eOpenLogicalChannel_separateStack) &&
 447             olc->forwardLogicalChannelParameters.dataType.choice ==
 448             eDataType_data &&
 449             olc->forwardLogicalChannelParameters.dataType.data.application.
 450             choice == eDataApplicationCapability_application_t120 &&
 451             olc->forwardLogicalChannelParameters.dataType.data.application.
 452             t120.choice == eDataProtocolCapability_separateLANStack &&
 453             olc->separateStack.networkAddress.choice ==
 454             eNetworkAccessParameters_networkAddress_localAreaAddress) {
 455                 ret = expect_t120(skb, ct, ctinfo, data, dataoff,
 456                                   &olc->separateStack.networkAddress.
 457                                   localAreaAddress);
 458                 if (ret < 0)
 459                         return -1;
 460         }
 461
 462         return 0;
 463 }
 464
 465 /****************************************************************************/
 466 static int process_olca(struct sk_buff *skb, struct nf_conn *ct,
 467                         enum ip_conntrack_info ctinfo,
 468                         unsigned char **data, int dataoff,
 469                         OpenLogicalChannelAck *olca)
 470 {
 471         H2250LogicalChannelAckParameters *ack;
 472         int ret;
 473
 474         pr_debug("nf_ct_h323: OpenLogicalChannelAck\n");
 475
 476         if ((olca->options &
 477              eOpenLogicalChannelAck_reverseLogicalChannelParameters) &&
 478             (olca->reverseLogicalChannelParameters.options &
 479              eOpenLogicalChannelAck_reverseLogicalChannelParameters_multiplexParameters)
 480             && (olca->reverseLogicalChannelParameters.multiplexParameters.
 481                 choice ==
 482                 eOpenLogicalChannelAck_reverseLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters))
 483         {
 484                 ret = process_h245_channel(skb, ct, ctinfo, data, dataoff,
 485                                            &olca->
 486                                            reverseLogicalChannelParameters.
 487                                            multiplexParameters.
 488                                            h2250LogicalChannelParameters);
 489                 if (ret < 0)
 490                         return -1;
 491         }
 492
 493         if ((olca->options &
 494              eOpenLogicalChannelAck_forwardMultiplexAckParameters) &&
 495             (olca->forwardMultiplexAckParameters.choice ==
 496              eOpenLogicalChannelAck_forwardMultiplexAckParameters_h2250LogicalChannelAckParameters))
 497         {
 498                 ack = &olca->forwardMultiplexAckParameters.
 499                     h2250LogicalChannelAckParameters;
 500                 if (ack->options &
 501                     eH2250LogicalChannelAckParameters_mediaChannel) {
 502                         /* RTP */
 503                         ret = expect_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
 504                                               &ack->mediaChannel);
 505                         if (ret < 0)
 506                                 return -1;
 507                 }
 508
 509                 if (ack->options &
 510                     eH2250LogicalChannelAckParameters_mediaControlChannel) {
 511                         /* RTCP */
 512                         ret = expect_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
 513                                               &ack->mediaControlChannel);
 514                         if (ret < 0)
 515                                 return -1;
 516                 }
 517         }
 518
 519         if ((olca->options & eOpenLogicalChannelAck_separateStack) &&
 520                 olca->separateStack.networkAddress.choice ==
 521                 eNetworkAccessParameters_networkAddress_localAreaAddress) {
 522                 ret = expect_t120(skb, ct, ctinfo, data, dataoff,
 523                                   &olca->separateStack.networkAddress.
 524                                   localAreaAddress);
 525                 if (ret < 0)
 526                         return -1;
 527         }
 528
 529         return 0;
 530 }
 531
 532 /****************************************************************************/
 533 static int process_h245(struct sk_buff *skb, struct nf_conn *ct,
 534                         enum ip_conntrack_info ctinfo,
 535                         unsigned char **data, int dataoff,
 536                         MultimediaSystemControlMessage *mscm)
 537 {
 538         switch (mscm->choice) {
 539         case eMultimediaSystemControlMessage_request:
 540                 if (mscm->request.choice ==
 541                     eRequestMessage_openLogicalChannel) {
 542                         return process_olc(skb, ct, ctinfo, data, dataoff,
 543                                            &mscm->request.openLogicalChannel);
 544                 }
 545                 pr_debug("nf_ct_h323: H.245 Request %d\n",
 546                          mscm->request.choice);
 547                 break;
 548         case eMultimediaSystemControlMessage_response:
 549                 if (mscm->response.choice ==
 550                     eResponseMessage_openLogicalChannelAck) {
 551                         return process_olca(skb, ct, ctinfo, data, dataoff,
 552                                             &mscm->response.
 553                                             openLogicalChannelAck);
 554                 }
 555                 pr_debug("nf_ct_h323: H.245 Response %d\n",
 556                          mscm->response.choice);
 557                 break;
 558         default:
 559                 pr_debug("nf_ct_h323: H.245 signal %d\n", mscm->choice);
 560                 break;
 561         }
 562
 563         return 0;
 564 }
 565
 566 /****************************************************************************/
 567 static int h245_help(struct sk_buff *skb, unsigned int protoff,
 568                      struct nf_conn *ct, enum ip_conntrack_info ctinfo)
 569 {
 570         static MultimediaSystemControlMessage mscm;
 571         unsigned char *data = NULL;
 572         int datalen;
 573         int dataoff;
 574         int ret;
 575
 576         /* Until there's been traffic both ways, don't look in packets. */
 577         if (ctinfo != IP_CT_ESTABLISHED &&
 578             ctinfo != IP_CT_ESTABLISHED + IP_CT_IS_REPLY) {
 579                 return NF_ACCEPT;
 580         }
 581         pr_debug("nf_ct_h245: skblen = %u\n", skb->len);
 582
 583         spin_lock_bh(&nf_h323_lock);
 584
 585         /* Process each TPKT */
 586         while (get_tpkt_data(skb, protoff, ct, ctinfo,
 587                              &data, &datalen, &dataoff)) {
 588                 pr_debug("nf_ct_h245: TPKT len=%d ", datalen);
 589                 NF_CT_DUMP_TUPLE(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
 590
 591                 /* Decode H.245 signal */
 592                 ret = DecodeMultimediaSystemControlMessage(data, datalen,
 593                                                            &mscm);
 594                 if (ret < 0) {
 595                         pr_debug("nf_ct_h245: decoding error: %s\n",
 596                                  ret == H323_ERROR_BOUND ?
 597                                  "out of bound" : "out of range");
 598                         /* We don't drop when decoding error */
 599                         break;
 600                 }
 601
 602                 /* Process H.245 signal */
 603                 if (process_h245(skb, ct, ctinfo, &data, dataoff, &mscm) < 0)
 604                         goto drop;
 605         }
 606
 607         spin_unlock_bh(&nf_h323_lock);
 608         return NF_ACCEPT;
 609
 610       drop:
 611         spin_unlock_bh(&nf_h323_lock);
 612         if (net_ratelimit())
 613                 printk("nf_ct_h245: packet dropped\n");
 614         return NF_DROP;
 615 }
 616
 617 /****************************************************************************/
 618 static const struct nf_conntrack_expect_policy h245_exp_policy = {
 619         .max_expected   = H323_RTP_CHANNEL_MAX * 4 + 2 /* T.120 */,
 620         .timeout        = 240,
 621 };
 622
 623 static struct nf_conntrack_helper nf_conntrack_helper_h245 __read_mostly = {
 624         .name                   = "H.245",
 625         .me                     = THIS_MODULE,
 626         .tuple.dst.protonum     = IPPROTO_UDP,
 627         .help                   = h245_help,
 628         .expect_policy          = &h245_exp_policy,
 629 };
 630
 631 /****************************************************************************/
 632 int get_h225_addr(struct nf_conn *ct, unsigned char *data,
 633                   TransportAddress *taddr,
 634                   union nf_inet_addr *addr, __be16 *port)
 635 {
 636         const unsigned char *p;
 637         int family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 638         int len;
 639
 640         switch (taddr->choice) {
 641         case eTransportAddress_ipAddress:
 642                 if (family != AF_INET)
 643                         return 0;
 644                 p = data + taddr->ipAddress.ip;
 645                 len = 4;
 646                 break;
 647         case eTransportAddress_ip6Address:
 648                 if (family != AF_INET6)
 649                         return 0;
 650                 p = data + taddr->ip6Address.ip;
 651                 len = 16;
 652                 break;
 653         default:
 654                 return 0;
 655         }
 656
 657         memcpy(addr, p, len);
 658         memset((void *)addr + len, 0, sizeof(*addr) - len);
 659         memcpy(port, p + len, sizeof(__be16));
 660
 661         return 1;
 662 }
 663
 664 /****************************************************************************/
 665 static int expect_h245(struct sk_buff *skb, struct nf_conn *ct,
 666                        enum ip_conntrack_info ctinfo,
 667                        unsigned char **data, int dataoff,
 668                        TransportAddress *taddr)
 669 {
 670         int dir = CTINFO2DIR(ctinfo);
 671         int ret = 0;
 672         __be16 port;
 673         union nf_inet_addr addr;
 674         struct nf_conntrack_expect *exp;
 675         typeof(nat_h245_hook) nat_h245;
 676
 677         /* Read h245Address */
 678         if (!get_h225_addr(ct, *data, taddr, &addr, &port) ||
 679             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
 680             port == 0)
 681                 return 0;
 682
 683         /* Create expect for h245 connection */
 684         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
 685                 return -1;
 686         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT,
 687                           ct->tuplehash[!dir].tuple.src.l3num,
 688                           &ct->tuplehash[!dir].tuple.src.u3,
 689                           &ct->tuplehash[!dir].tuple.dst.u3,
 690                           IPPROTO_TCP, NULL, &port);
 691         exp->helper = &nf_conntrack_helper_h245;
 692
 693         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 694                    &ct->tuplehash[!dir].tuple.dst.u3,
 695                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 696             (nat_h245 = rcu_dereference(nat_h245_hook)) &&
 697             ct->status & IPS_NAT_MASK) {
 698                 /* NAT needed */
 699                 ret = nat_h245(skb, ct, ctinfo, data, dataoff, taddr,
 700                                port, exp);
 701         } else {                /* Conntrack only */
 702                 if (nf_ct_expect_related(exp) == 0) {
 703                         pr_debug("nf_ct_q931: expect H.245 ");
 704                         NF_CT_DUMP_TUPLE(&exp->tuple);
 705                 } else
 706                         ret = -1;
 707         }
 708
 709         nf_ct_expect_put(exp);
 710
 711         return ret;
 712 }
 713
 714 /* If the calling party is on the same side of the forward-to party,
 715  * we don't need to track the second call */
 716 static int callforward_do_filter(const union nf_inet_addr *src,
 717                                  const union nf_inet_addr *dst, int family)
 718 {
 719         const struct nf_afinfo *afinfo;
 720         struct flowi fl1, fl2;
 721         int ret = 0;
 722
 723         /* rcu_read_lock()ed by nf_hook_slow() */
 724         afinfo = nf_get_afinfo(family);
 725         if (!afinfo)
 726                 return 0;
 727
 728         memset(&fl1, 0, sizeof(fl1));
 729         memset(&fl2, 0, sizeof(fl2));
 730
 731         switch (family) {
 732         case AF_INET: {
 733                 struct rtable *rt1, *rt2;
 734
 735                 fl1.fl4_dst = src->ip;
 736                 fl2.fl4_dst = dst->ip;
 737                 if (!afinfo->route((struct dst_entry **)&rt1, &fl1)) {
 738                         if (!afinfo->route((struct dst_entry **)&rt2, &fl2)) {
 739                                 if (rt1->rt_gateway == rt2->rt_gateway &&
 740                                     rt1->u.dst.dev  == rt2->u.dst.dev)
 741                                         ret = 1;
 742                                 dst_release(&rt2->u.dst);
 743                         }
 744                         dst_release(&rt1->u.dst);
 745                 }
 746                 break;
 747         }
 748 #if defined(CONFIG_NF_CONNTRACK_IPV6) || \
 749     defined(CONFIG_NF_CONNTRACK_IPV6_MODULE)
 750         case AF_INET6: {
 751                 struct rt6_info *rt1, *rt2;
 752
 753                 memcpy(&fl1.fl6_dst, src, sizeof(fl1.fl6_dst));
 754                 memcpy(&fl2.fl6_dst, dst, sizeof(fl2.fl6_dst));
 755                 if (!afinfo->route((struct dst_entry **)&rt1, &fl1)) {
 756                         if (!afinfo->route((struct dst_entry **)&rt2, &fl2)) {
 757                                 if (!memcmp(&rt1->rt6i_gateway, &rt2->rt6i_gateway,
 758                                             sizeof(rt1->rt6i_gateway)) &&
 759                                     rt1->u.dst.dev == rt2->u.dst.dev)
 760                                         ret = 1;
 761                                 dst_release(&rt2->u.dst);
 762                         }
 763                         dst_release(&rt1->u.dst);
 764                 }
 765                 break;
 766         }
 767 #endif
 768         }
 769         return ret;
 770
 771 }
 772
 773 /****************************************************************************/
 774 static int expect_callforwarding(struct sk_buff *skb,
 775                                  struct nf_conn *ct,
 776                                  enum ip_conntrack_info ctinfo,
 777                                  unsigned char **data, int dataoff,
 778                                  TransportAddress *taddr)
 779 {
 780         int dir = CTINFO2DIR(ctinfo);
 781         int ret = 0;
 782         __be16 port;
 783         union nf_inet_addr addr;
 784         struct nf_conntrack_expect *exp;
 785         typeof(nat_callforwarding_hook) nat_callforwarding;
 786
 787         /* Read alternativeAddress */
 788         if (!get_h225_addr(ct, *data, taddr, &addr, &port) || port == 0)
 789                 return 0;
 790
 791         /* If the calling party is on the same side of the forward-to party,
 792          * we don't need to track the second call */
 793         if (callforward_filter &&
 794             callforward_do_filter(&addr, &ct->tuplehash[!dir].tuple.src.u3,
 795                                   ct->tuplehash[!dir].tuple.src.l3num)) {
 796                 pr_debug("nf_ct_q931: Call Forwarding not tracked\n");
 797                 return 0;
 798         }
 799
 800         /* Create expect for the second call leg */
 801         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
 802                 return -1;
 803         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT,
 804                           ct->tuplehash[!dir].tuple.src.l3num,
 805                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
 806                           IPPROTO_TCP, NULL, &port);
 807         exp->helper = nf_conntrack_helper_q931;
 808
 809         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 810                    &ct->tuplehash[!dir].tuple.dst.u3,
 811                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 812             (nat_callforwarding = rcu_dereference(nat_callforwarding_hook)) &&
 813             ct->status & IPS_NAT_MASK) {
 814                 /* Need NAT */
 815                 ret = nat_callforwarding(skb, ct, ctinfo, data, dataoff,
 816                                          taddr, port, exp);
 817         } else {                /* Conntrack only */
 818                 if (nf_ct_expect_related(exp) == 0) {
 819                         pr_debug("nf_ct_q931: expect Call Forwarding ");
 820                         NF_CT_DUMP_TUPLE(&exp->tuple);
 821                 } else
 822                         ret = -1;
 823         }
 824
 825         nf_ct_expect_put(exp);
 826
 827         return ret;
 828 }
 829
 830 /****************************************************************************/
 831 static int process_setup(struct sk_buff *skb, struct nf_conn *ct,
 832                          enum ip_conntrack_info ctinfo,
 833                          unsigned char **data, int dataoff,
 834                          Setup_UUIE *setup)
 835 {
 836         int dir = CTINFO2DIR(ctinfo);
 837         int ret;
 838         int i;
 839         __be16 port;
 840         union nf_inet_addr addr;
 841         typeof(set_h225_addr_hook) set_h225_addr;
 842
 843         pr_debug("nf_ct_q931: Setup\n");
 844
 845         if (setup->options & eSetup_UUIE_h245Address) {
 846                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
 847                                   &setup->h245Address);
 848                 if (ret < 0)
 849                         return -1;
 850         }
 851
 852         set_h225_addr = rcu_dereference(set_h225_addr_hook);
 853         if ((setup->options & eSetup_UUIE_destCallSignalAddress) &&
 854             (set_h225_addr) && ct->status & IPS_NAT_MASK &&
 855             get_h225_addr(ct, *data, &setup->destCallSignalAddress,
 856                           &addr, &port) &&
 857             memcmp(&addr, &ct->tuplehash[!dir].tuple.src.u3, sizeof(addr))) {
 858                 pr_debug("nf_ct_q931: set destCallSignalAddress "
 859                          NIP6_FMT ":%hu->" NIP6_FMT ":%hu\n",
 860                          NIP6(*(struct in6_addr *)&addr), ntohs(port),
 861                          NIP6(*(struct in6_addr *)&ct->tuplehash[!dir].tuple.src.u3),
 862                          ntohs(ct->tuplehash[!dir].tuple.src.u.tcp.port));
 863                 ret = set_h225_addr(skb, data, dataoff,
 864                                     &setup->destCallSignalAddress,
 865                                     &ct->tuplehash[!dir].tuple.src.u3,
 866                                     ct->tuplehash[!dir].tuple.src.u.tcp.port);
 867                 if (ret < 0)
 868                         return -1;
 869         }
 870
 871         if ((setup->options & eSetup_UUIE_sourceCallSignalAddress) &&
 872             (set_h225_addr) && ct->status & IPS_NAT_MASK &&
 873             get_h225_addr(ct, *data, &setup->sourceCallSignalAddress,
 874                           &addr, &port) &&
 875             memcmp(&addr, &ct->tuplehash[!dir].tuple.dst.u3, sizeof(addr))) {
 876                 pr_debug("nf_ct_q931: set sourceCallSignalAddress "
 877                          NIP6_FMT ":%hu->" NIP6_FMT ":%hu\n",
 878                          NIP6(*(struct in6_addr *)&addr), ntohs(port),
 879                          NIP6(*(struct in6_addr *)&ct->tuplehash[!dir].tuple.dst.u3),
 880                          ntohs(ct->tuplehash[!dir].tuple.dst.u.tcp.port));
 881                 ret = set_h225_addr(skb, data, dataoff,
 882                                     &setup->sourceCallSignalAddress,
 883                                     &ct->tuplehash[!dir].tuple.dst.u3,
 884                                     ct->tuplehash[!dir].tuple.dst.u.tcp.port);
 885                 if (ret < 0)
 886                         return -1;
 887         }
 888
 889         if (setup->options & eSetup_UUIE_fastStart) {
 890                 for (i = 0; i < setup->fastStart.count; i++) {
 891                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
 892                                           &setup->fastStart.item[i]);
 893                         if (ret < 0)
 894                                 return -1;
 895                 }
 896         }
 897
 898         return 0;
 899 }
 900
 901 /****************************************************************************/
 902 static int process_callproceeding(struct sk_buff *skb,
 903                                   struct nf_conn *ct,
 904                                   enum ip_conntrack_info ctinfo,
 905                                   unsigned char **data, int dataoff,
 906                                   CallProceeding_UUIE *callproc)
 907 {
 908         int ret;
 909         int i;
 910
 911         pr_debug("nf_ct_q931: CallProceeding\n");
 912
 913         if (callproc->options & eCallProceeding_UUIE_h245Address) {
 914                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
 915                                   &callproc->h245Address);
 916                 if (ret < 0)
 917                         return -1;
 918         }
 919
 920         if (callproc->options & eCallProceeding_UUIE_fastStart) {
 921                 for (i = 0; i < callproc->fastStart.count; i++) {
 922                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
 923                                           &callproc->fastStart.item[i]);
 924                         if (ret < 0)
 925                                 return -1;
 926                 }
 927         }
 928
 929         return 0;
 930 }
 931
 932 /****************************************************************************/
 933 static int process_connect(struct sk_buff *skb, struct nf_conn *ct,
 934                            enum ip_conntrack_info ctinfo,
 935                            unsigned char **data, int dataoff,
 936                            Connect_UUIE *connect)
 937 {
 938         int ret;
 939         int i;
 940
 941         pr_debug("nf_ct_q931: Connect\n");
 942
 943         if (connect->options & eConnect_UUIE_h245Address) {
 944                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
 945                                   &connect->h245Address);
 946                 if (ret < 0)
 947                         return -1;
 948         }
 949
 950         if (connect->options & eConnect_UUIE_fastStart) {
 951                 for (i = 0; i < connect->fastStart.count; i++) {
 952                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
 953                                           &connect->fastStart.item[i]);
 954                         if (ret < 0)
 955                                 return -1;
 956                 }
 957         }
 958
 959         return 0;
 960 }
 961
 962 /****************************************************************************/
 963 static int process_alerting(struct sk_buff *skb, struct nf_conn *ct,
 964                             enum ip_conntrack_info ctinfo,
 965                             unsigned char **data, int dataoff,
 966                             Alerting_UUIE *alert)
 967 {
 968         int ret;
 969         int i;
 970
 971         pr_debug("nf_ct_q931: Alerting\n");
 972
 973         if (alert->options & eAlerting_UUIE_h245Address) {
 974                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
 975                                   &alert->h245Address);
 976                 if (ret < 0)
 977                         return -1;
 978         }
 979
 980         if (alert->options & eAlerting_UUIE_fastStart) {
 981                 for (i = 0; i < alert->fastStart.count; i++) {
 982                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
 983                                           &alert->fastStart.item[i]);
 984                         if (ret < 0)
 985                                 return -1;
 986                 }
 987         }
 988
 989         return 0;
 990 }
 991
 992 /****************************************************************************/
 993 static int process_facility(struct sk_buff *skb, struct nf_conn *ct,
 994                             enum ip_conntrack_info ctinfo,
 995                             unsigned char **data, int dataoff,
 996                             Facility_UUIE *facility)
 997 {
 998         int ret;
 999         int i;
1000
1001         pr_debug("nf_ct_q931: Facility\n");
1002
1003         if (facility->reason.choice == eFacilityReason_callForwarded) {
1004                 if (facility->options & eFacility_UUIE_alternativeAddress)
1005                         return expect_callforwarding(skb, ct, ctinfo, data,
1006                                                      dataoff,
1007                                                      &facility->
1008                                                      alternativeAddress);
1009                 return 0;
1010         }
1011
1012         if (facility->options & eFacility_UUIE_h245Address) {
1013                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
1014                                   &facility->h245Address);
1015                 if (ret < 0)
1016                         return -1;
1017         }
1018
1019         if (facility->options & eFacility_UUIE_fastStart) {
1020                 for (i = 0; i < facility->fastStart.count; i++) {
1021                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
1022                                           &facility->fastStart.item[i]);
1023                         if (ret < 0)
1024                                 return -1;
1025                 }
1026         }
1027
1028         return 0;
1029 }
1030
1031 /****************************************************************************/
1032 static int process_progress(struct sk_buff *skb, struct nf_conn *ct,
1033                             enum ip_conntrack_info ctinfo,
1034                             unsigned char **data, int dataoff,
1035                             Progress_UUIE *progress)
1036 {
1037         int ret;
1038         int i;
1039
1040         pr_debug("nf_ct_q931: Progress\n");
1041
1042         if (progress->options & eProgress_UUIE_h245Address) {
1043                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
1044                                   &progress->h245Address);
1045                 if (ret < 0)
1046                         return -1;
1047         }
1048
1049         if (progress->options & eProgress_UUIE_fastStart) {
1050                 for (i = 0; i < progress->fastStart.count; i++) {
1051                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
1052                                           &progress->fastStart.item[i]);
1053                         if (ret < 0)
1054                                 return -1;
1055                 }
1056         }
1057
1058         return 0;
1059 }
1060
1061 /****************************************************************************/
1062 static int process_q931(struct sk_buff *skb, struct nf_conn *ct,
1063                         enum ip_conntrack_info ctinfo,
1064                         unsigned char **data, int dataoff, Q931 *q931)
1065 {
1066         H323_UU_PDU *pdu = &q931->UUIE.h323_uu_pdu;
1067         int i;
1068         int ret = 0;
1069
1070         switch (pdu->h323_message_body.choice) {
1071         case eH323_UU_PDU_h323_message_body_setup:
1072                 ret = process_setup(skb, ct, ctinfo, data, dataoff,
1073                                     &pdu->h323_message_body.setup);
1074                 break;
1075         case eH323_UU_PDU_h323_message_body_callProceeding:
1076                 ret = process_callproceeding(skb, ct, ctinfo, data, dataoff,
1077                                              &pdu->h323_message_body.
1078                                              callProceeding);
1079                 break;
1080         case eH323_UU_PDU_h323_message_body_connect:
1081                 ret = process_connect(skb, ct, ctinfo, data, dataoff,
1082                                       &pdu->h323_message_body.connect);
1083                 break;
1084         case eH323_UU_PDU_h323_message_body_alerting:
1085                 ret = process_alerting(skb, ct, ctinfo, data, dataoff,
1086                                        &pdu->h323_message_body.alerting);
1087                 break;
1088         case eH323_UU_PDU_h323_message_body_facility:
1089                 ret = process_facility(skb, ct, ctinfo, data, dataoff,
1090                                        &pdu->h323_message_body.facility);
1091                 break;
1092         case eH323_UU_PDU_h323_message_body_progress:
1093                 ret = process_progress(skb, ct, ctinfo, data, dataoff,
1094                                        &pdu->h323_message_body.progress);
1095                 break;
1096         default:
1097                 pr_debug("nf_ct_q931: Q.931 signal %d\n",
1098                          pdu->h323_message_body.choice);
1099                 break;
1100         }
1101
1102         if (ret < 0)
1103                 return -1;
1104
1105         if (pdu->options & eH323_UU_PDU_h245Control) {
1106                 for (i = 0; i < pdu->h245Control.count; i++) {
1107                         ret = process_h245(skb, ct, ctinfo, data, dataoff,
1108                                            &pdu->h245Control.item[i]);
1109                         if (ret < 0)
1110                                 return -1;
1111                 }
1112         }
1113
1114         return 0;
1115 }
1116
1117 /****************************************************************************/
1118 static int q931_help(struct sk_buff *skb, unsigned int protoff,
1119                      struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1120 {
1121         static Q931 q931;
1122         unsigned char *data = NULL;
1123         int datalen;
1124         int dataoff;
1125         int ret;
1126
1127         /* Until there's been traffic both ways, don't look in packets. */
1128         if (ctinfo != IP_CT_ESTABLISHED &&
1129             ctinfo != IP_CT_ESTABLISHED + IP_CT_IS_REPLY) {
1130                 return NF_ACCEPT;
1131         }
1132         pr_debug("nf_ct_q931: skblen = %u\n", skb->len);
1133
1134         spin_lock_bh(&nf_h323_lock);
1135
1136         /* Process each TPKT */
1137         while (get_tpkt_data(skb, protoff, ct, ctinfo,
1138                              &data, &datalen, &dataoff)) {
1139                 pr_debug("nf_ct_q931: TPKT len=%d ", datalen);
1140                 NF_CT_DUMP_TUPLE(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1141
1142                 /* Decode Q.931 signal */
1143                 ret = DecodeQ931(data, datalen, &q931);
1144                 if (ret < 0) {
1145                         pr_debug("nf_ct_q931: decoding error: %s\n",
1146                                  ret == H323_ERROR_BOUND ?
1147                                  "out of bound" : "out of range");
1148                         /* We don't drop when decoding error */
1149                         break;
1150                 }
1151
1152                 /* Process Q.931 signal */
1153                 if (process_q931(skb, ct, ctinfo, &data, dataoff, &q931) < 0)
1154                         goto drop;
1155         }
1156
1157         spin_unlock_bh(&nf_h323_lock);
1158         return NF_ACCEPT;
1159
1160       drop:
1161         spin_unlock_bh(&nf_h323_lock);
1162         if (net_ratelimit())
1163                 printk("nf_ct_q931: packet dropped\n");
1164         return NF_DROP;
1165 }
1166
1167 /****************************************************************************/
1168 static const struct nf_conntrack_expect_policy q931_exp_policy = {
1169         /* T.120 and H.245 */
1170         .max_expected           = H323_RTP_CHANNEL_MAX * 4 + 4,
1171         .timeout                = 240,
1172 };
1173
1174 static struct nf_conntrack_helper nf_conntrack_helper_q931[] __read_mostly = {
1175         {
1176                 .name                   = "Q.931",
1177                 .me                     = THIS_MODULE,
1178                 .tuple.src.l3num        = AF_INET,
1179                 .tuple.src.u.tcp.port   = __constant_htons(Q931_PORT),
1180                 .tuple.dst.protonum     = IPPROTO_TCP,
1181                 .help                   = q931_help,
1182                 .expect_policy          = &q931_exp_policy,
1183         },
1184         {
1185                 .name                   = "Q.931",
1186                 .me                     = THIS_MODULE,
1187                 .tuple.src.l3num        = AF_INET6,
1188                 .tuple.src.u.tcp.port   = __constant_htons(Q931_PORT),
1189                 .tuple.dst.protonum     = IPPROTO_TCP,
1190                 .help                   = q931_help,
1191                 .expect_policy          = &q931_exp_policy,
1192         },
1193 };
1194
1195 /****************************************************************************/
1196 static unsigned char *get_udp_data(struct sk_buff *skb, unsigned int protoff,
1197                                    int *datalen)
1198 {
1199         const struct udphdr *uh;
1200         struct udphdr _uh;
1201         int dataoff;
1202
1203         uh = skb_header_pointer(skb, protoff, sizeof(_uh), &_uh);
1204         if (uh == NULL)
1205                 return NULL;
1206         dataoff = protoff + sizeof(_uh);
1207         if (dataoff >= skb->len)
1208                 return NULL;
1209         *datalen = skb->len - dataoff;
1210         return skb_header_pointer(skb, dataoff, *datalen, h323_buffer);
1211 }
1212
1213 /****************************************************************************/
1214 static struct nf_conntrack_expect *find_expect(struct nf_conn *ct,
1215                                                union nf_inet_addr *addr,
1216                                                __be16 port)
1217 {
1218         struct nf_conntrack_expect *exp;
1219         struct nf_conntrack_tuple tuple;
1220
1221         memset(&tuple.src.u3, 0, sizeof(tuple.src.u3));
1222         tuple.src.u.tcp.port = 0;
1223         memcpy(&tuple.dst.u3, addr, sizeof(tuple.dst.u3));
1224         tuple.dst.u.tcp.port = port;
1225         tuple.dst.protonum = IPPROTO_TCP;
1226
1227         exp = __nf_ct_expect_find(&tuple);
1228         if (exp && exp->master == ct)
1229                 return exp;
1230         return NULL;
1231 }
1232
1233 /****************************************************************************/
1234 static int set_expect_timeout(struct nf_conntrack_expect *exp,
1235                               unsigned timeout)
1236 {
1237         if (!exp || !del_timer(&exp->timeout))
1238                 return 0;
1239
1240         exp->timeout.expires = jiffies + timeout * HZ;
1241         add_timer(&exp->timeout);
1242
1243         return 1;
1244 }
1245
1246 /****************************************************************************/
1247 static int expect_q931(struct sk_buff *skb, struct nf_conn *ct,
1248                        enum ip_conntrack_info ctinfo,
1249                        unsigned char **data,
1250                        TransportAddress *taddr, int count)
1251 {
1252         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1253         int dir = CTINFO2DIR(ctinfo);
1254         int ret = 0;
1255         int i;
1256         __be16 port;
1257         union nf_inet_addr addr;
1258         struct nf_conntrack_expect *exp;
1259         typeof(nat_q931_hook) nat_q931;
1260
1261         /* Look for the first related address */
1262         for (i = 0; i < count; i++) {
1263                 if (get_h225_addr(ct, *data, &taddr[i], &addr, &port) &&
1264                     memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3,
1265                            sizeof(addr)) == 0 && port != 0)
1266                         break;
1267         }
1268
1269         if (i >= count)         /* Not found */
1270                 return 0;
1271
1272         /* Create expect for Q.931 */
1273         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1274                 return -1;
1275         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT,
1276                           ct->tuplehash[!dir].tuple.src.l3num,
1277                           gkrouted_only ? /* only accept calls from GK? */
1278                                 &ct->tuplehash[!dir].tuple.src.u3 : NULL,
1279                           &ct->tuplehash[!dir].tuple.dst.u3,
1280                           IPPROTO_TCP, NULL, &port);
1281         exp->helper = nf_conntrack_helper_q931;
1282         exp->flags = NF_CT_EXPECT_PERMANENT;    /* Accept multiple calls */
1283
1284         nat_q931 = rcu_dereference(nat_q931_hook);
1285         if (nat_q931 && ct->status & IPS_NAT_MASK) {    /* Need NAT */
1286                 ret = nat_q931(skb, ct, ctinfo, data, taddr, i, port, exp);
1287         } else {                /* Conntrack only */
1288                 if (nf_ct_expect_related(exp) == 0) {
1289                         pr_debug("nf_ct_ras: expect Q.931 ");
1290                         NF_CT_DUMP_TUPLE(&exp->tuple);
1291
1292                         /* Save port for looking up expect in processing RCF */
1293                         info->sig_port[dir] = port;
1294                 } else
1295                         ret = -1;
1296         }
1297
1298         nf_ct_expect_put(exp);
1299
1300         return ret;
1301 }
1302
1303 /****************************************************************************/
1304 static int process_grq(struct sk_buff *skb, struct nf_conn *ct,
1305                        enum ip_conntrack_info ctinfo,
1306                        unsigned char **data, GatekeeperRequest *grq)
1307 {
1308         typeof(set_ras_addr_hook) set_ras_addr;
1309
1310         pr_debug("nf_ct_ras: GRQ\n");
1311
1312         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1313         if (set_ras_addr && ct->status & IPS_NAT_MASK)  /* NATed */
1314                 return set_ras_addr(skb, ct, ctinfo, data,
1315                                     &grq->rasAddress, 1);
1316         return 0;
1317 }
1318
1319 /****************************************************************************/
1320 static int process_gcf(struct sk_buff *skb, struct nf_conn *ct,
1321                        enum ip_conntrack_info ctinfo,
1322                        unsigned char **data, GatekeeperConfirm *gcf)
1323 {
1324         int dir = CTINFO2DIR(ctinfo);
1325         int ret = 0;
1326         __be16 port;
1327         union nf_inet_addr addr;
1328         struct nf_conntrack_expect *exp;
1329
1330         pr_debug("nf_ct_ras: GCF\n");
1331
1332         if (!get_h225_addr(ct, *data, &gcf->rasAddress, &addr, &port))
1333                 return 0;
1334
1335         /* Registration port is the same as discovery port */
1336         if (!memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1337             port == ct->tuplehash[dir].tuple.src.u.udp.port)
1338                 return 0;
1339
1340         /* Avoid RAS expectation loops. A GCF is never expected. */
1341         if (test_bit(IPS_EXPECTED_BIT, &ct->status))
1342                 return 0;
1343
1344         /* Need new expect */
1345         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1346                 return -1;
1347         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT,
1348                           ct->tuplehash[!dir].tuple.src.l3num,
1349                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1350                           IPPROTO_UDP, NULL, &port);
1351         exp->helper = nf_conntrack_helper_ras;
1352
1353         if (nf_ct_expect_related(exp) == 0) {
1354                 pr_debug("nf_ct_ras: expect RAS ");
1355                 NF_CT_DUMP_TUPLE(&exp->tuple);
1356         } else
1357                 ret = -1;
1358
1359         nf_ct_expect_put(exp);
1360
1361         return ret;
1362 }
1363
1364 /****************************************************************************/
1365 static int process_rrq(struct sk_buff *skb, struct nf_conn *ct,
1366                        enum ip_conntrack_info ctinfo,
1367                        unsigned char **data, RegistrationRequest *rrq)
1368 {
1369         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1370         int ret;
1371         typeof(set_ras_addr_hook) set_ras_addr;
1372
1373         pr_debug("nf_ct_ras: RRQ\n");
1374
1375         ret = expect_q931(skb, ct, ctinfo, data,
1376                           rrq->callSignalAddress.item,
1377                           rrq->callSignalAddress.count);
1378         if (ret < 0)
1379                 return -1;
1380
1381         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1382         if (set_ras_addr && ct->status & IPS_NAT_MASK) {
1383                 ret = set_ras_addr(skb, ct, ctinfo, data,
1384                                    rrq->rasAddress.item,
1385                                    rrq->rasAddress.count);
1386                 if (ret < 0)
1387                         return -1;
1388         }
1389
1390         if (rrq->options & eRegistrationRequest_timeToLive) {
1391                 pr_debug("nf_ct_ras: RRQ TTL = %u seconds\n", rrq->timeToLive);
1392                 info->timeout = rrq->timeToLive;
1393         } else
1394                 info->timeout = default_rrq_ttl;
1395
1396         return 0;
1397 }
1398
1399 /****************************************************************************/
1400 static int process_rcf(struct sk_buff *skb, struct nf_conn *ct,
1401                        enum ip_conntrack_info ctinfo,
1402                        unsigned char **data, RegistrationConfirm *rcf)
1403 {
1404         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1405         int dir = CTINFO2DIR(ctinfo);
1406         int ret;
1407         struct nf_conntrack_expect *exp;
1408         typeof(set_sig_addr_hook) set_sig_addr;
1409
1410         pr_debug("nf_ct_ras: RCF\n");
1411
1412         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1413         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1414                 ret = set_sig_addr(skb, ct, ctinfo, data,
1415                                         rcf->callSignalAddress.item,
1416                                         rcf->callSignalAddress.count);
1417                 if (ret < 0)
1418                         return -1;
1419         }
1420
1421         if (rcf->options & eRegistrationConfirm_timeToLive) {
1422                 pr_debug("nf_ct_ras: RCF TTL = %u seconds\n", rcf->timeToLive);
1423                 info->timeout = rcf->timeToLive;
1424         }
1425
1426         if (info->timeout > 0) {
1427                 pr_debug("nf_ct_ras: set RAS connection timeout to "
1428                          "%u seconds\n", info->timeout);
1429                 nf_ct_refresh(ct, skb, info->timeout * HZ);
1430
1431                 /* Set expect timeout */
1432                 spin_lock_bh(&nf_conntrack_lock);
1433                 exp = find_expect(ct, &ct->tuplehash[dir].tuple.dst.u3,
1434                                   info->sig_port[!dir]);
1435                 if (exp) {
1436                         pr_debug("nf_ct_ras: set Q.931 expect "
1437                                  "timeout to %u seconds for",
1438                                  info->timeout);
1439                         NF_CT_DUMP_TUPLE(&exp->tuple);
1440                         set_expect_timeout(exp, info->timeout);
1441                 }
1442                 spin_unlock_bh(&nf_conntrack_lock);
1443         }
1444
1445         return 0;
1446 }
1447
1448 /****************************************************************************/
1449 static int process_urq(struct sk_buff *skb, struct nf_conn *ct,
1450                        enum ip_conntrack_info ctinfo,
1451                        unsigned char **data, UnregistrationRequest *urq)
1452 {
1453         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1454         int dir = CTINFO2DIR(ctinfo);
1455         int ret;
1456         typeof(set_sig_addr_hook) set_sig_addr;
1457
1458         pr_debug("nf_ct_ras: URQ\n");
1459
1460         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1461         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1462                 ret = set_sig_addr(skb, ct, ctinfo, data,
1463                                    urq->callSignalAddress.item,
1464                                    urq->callSignalAddress.count);
1465                 if (ret < 0)
1466                         return -1;
1467         }
1468
1469         /* Clear old expect */
1470         nf_ct_remove_expectations(ct);
1471         info->sig_port[dir] = 0;
1472         info->sig_port[!dir] = 0;
1473
1474         /* Give it 30 seconds for UCF or URJ */
1475         nf_ct_refresh(ct, skb, 30 * HZ);
1476
1477         return 0;
1478 }
1479
1480 /****************************************************************************/
1481 static int process_arq(struct sk_buff *skb, struct nf_conn *ct,
1482                        enum ip_conntrack_info ctinfo,
1483                        unsigned char **data, AdmissionRequest *arq)
1484 {
1485         const struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1486         int dir = CTINFO2DIR(ctinfo);
1487         __be16 port;
1488         union nf_inet_addr addr;
1489         typeof(set_h225_addr_hook) set_h225_addr;
1490
1491         pr_debug("nf_ct_ras: ARQ\n");
1492
1493         set_h225_addr = rcu_dereference(set_h225_addr_hook);
1494         if ((arq->options & eAdmissionRequest_destCallSignalAddress) &&
1495             get_h225_addr(ct, *data, &arq->destCallSignalAddress,
1496                           &addr, &port) &&
1497             !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1498             port == info->sig_port[dir] &&
1499             set_h225_addr && ct->status & IPS_NAT_MASK) {
1500                 /* Answering ARQ */
1501                 return set_h225_addr(skb, data, 0,
1502                                      &arq->destCallSignalAddress,
1503                                      &ct->tuplehash[!dir].tuple.dst.u3,
1504                                      info->sig_port[!dir]);
1505         }
1506
1507         if ((arq->options & eAdmissionRequest_srcCallSignalAddress) &&
1508             get_h225_addr(ct, *data, &arq->srcCallSignalAddress,
1509                           &addr, &port) &&
1510             !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1511             set_h225_addr && ct->status & IPS_NAT_MASK) {
1512                 /* Calling ARQ */
1513                 return set_h225_addr(skb, data, 0,
1514                                      &arq->srcCallSignalAddress,
1515                                      &ct->tuplehash[!dir].tuple.dst.u3,
1516                                      port);
1517         }
1518
1519         return 0;
1520 }
1521
1522 /****************************************************************************/
1523 static int process_acf(struct sk_buff *skb, struct nf_conn *ct,
1524                        enum ip_conntrack_info ctinfo,
1525                        unsigned char **data, AdmissionConfirm *acf)
1526 {
1527         int dir = CTINFO2DIR(ctinfo);
1528         int ret = 0;
1529         __be16 port;
1530         union nf_inet_addr addr;
1531         struct nf_conntrack_expect *exp;
1532         typeof(set_sig_addr_hook) set_sig_addr;
1533
1534         pr_debug("nf_ct_ras: ACF\n");
1535
1536         if (!get_h225_addr(ct, *data, &acf->destCallSignalAddress,
1537                            &addr, &port))
1538                 return 0;
1539
1540         if (!memcmp(&addr, &ct->tuplehash[dir].tuple.dst.u3, sizeof(addr))) {
1541                 /* Answering ACF */
1542                 set_sig_addr = rcu_dereference(set_sig_addr_hook);
1543                 if (set_sig_addr && ct->status & IPS_NAT_MASK)
1544                         return set_sig_addr(skb, ct, ctinfo, data,
1545                                             &acf->destCallSignalAddress, 1);
1546                 return 0;
1547         }
1548
1549         /* Need new expect */
1550         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1551                 return -1;
1552         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT,
1553                           ct->tuplehash[!dir].tuple.src.l3num,
1554                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1555                           IPPROTO_TCP, NULL, &port);
1556         exp->flags = NF_CT_EXPECT_PERMANENT;
1557         exp->helper = nf_conntrack_helper_q931;
1558
1559         if (nf_ct_expect_related(exp) == 0) {
1560                 pr_debug("nf_ct_ras: expect Q.931 ");
1561                 NF_CT_DUMP_TUPLE(&exp->tuple);
1562         } else
1563                 ret = -1;
1564
1565         nf_ct_expect_put(exp);
1566
1567         return ret;
1568 }
1569
1570 /****************************************************************************/
1571 static int process_lrq(struct sk_buff *skb, struct nf_conn *ct,
1572                        enum ip_conntrack_info ctinfo,
1573                        unsigned char **data, LocationRequest *lrq)
1574 {
1575         typeof(set_ras_addr_hook) set_ras_addr;
1576
1577         pr_debug("nf_ct_ras: LRQ\n");
1578
1579         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1580         if (set_ras_addr && ct->status & IPS_NAT_MASK)
1581                 return set_ras_addr(skb, ct, ctinfo, data,
1582                                     &lrq->replyAddress, 1);
1583         return 0;
1584 }
1585
1586 /****************************************************************************/
1587 static int process_lcf(struct sk_buff *skb, struct nf_conn *ct,
1588                        enum ip_conntrack_info ctinfo,
1589                        unsigned char **data, LocationConfirm *lcf)
1590 {
1591         int dir = CTINFO2DIR(ctinfo);
1592         int ret = 0;
1593         __be16 port;
1594         union nf_inet_addr addr;
1595         struct nf_conntrack_expect *exp;
1596
1597         pr_debug("nf_ct_ras: LCF\n");
1598
1599         if (!get_h225_addr(ct, *data, &lcf->callSignalAddress,
1600                            &addr, &port))
1601                 return 0;
1602
1603         /* Need new expect for call signal */
1604         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1605                 return -1;
1606         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT,
1607                           ct->tuplehash[!dir].tuple.src.l3num,
1608                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1609                           IPPROTO_TCP, NULL, &port);
1610         exp->flags = NF_CT_EXPECT_PERMANENT;
1611         exp->helper = nf_conntrack_helper_q931;
1612
1613         if (nf_ct_expect_related(exp) == 0) {
1614                 pr_debug("nf_ct_ras: expect Q.931 ");
1615                 NF_CT_DUMP_TUPLE(&exp->tuple);
1616         } else
1617                 ret = -1;
1618
1619         nf_ct_expect_put(exp);
1620
1621         /* Ignore rasAddress */
1622
1623         return ret;
1624 }
1625
1626 /****************************************************************************/
1627 static int process_irr(struct sk_buff *skb, struct nf_conn *ct,
1628                        enum ip_conntrack_info ctinfo,
1629                        unsigned char **data, InfoRequestResponse *irr)
1630 {
1631         int ret;
1632         typeof(set_ras_addr_hook) set_ras_addr;
1633         typeof(set_sig_addr_hook) set_sig_addr;
1634
1635         pr_debug("nf_ct_ras: IRR\n");
1636
1637         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1638         if (set_ras_addr && ct->status & IPS_NAT_MASK) {
1639                 ret = set_ras_addr(skb, ct, ctinfo, data,
1640                                    &irr->rasAddress, 1);
1641                 if (ret < 0)
1642                         return -1;
1643         }
1644
1645         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1646         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1647                 ret = set_sig_addr(skb, ct, ctinfo, data,
1648                                         irr->callSignalAddress.item,
1649                                         irr->callSignalAddress.count);
1650                 if (ret < 0)
1651                         return -1;
1652         }
1653
1654         return 0;
1655 }
1656
1657 /****************************************************************************/
1658 static int process_ras(struct sk_buff *skb, struct nf_conn *ct,
1659                        enum ip_conntrack_info ctinfo,
1660                        unsigned char **data, RasMessage *ras)
1661 {
1662         switch (ras->choice) {
1663         case eRasMessage_gatekeeperRequest:
1664                 return process_grq(skb, ct, ctinfo, data,
1665                                    &ras->gatekeeperRequest);
1666         case eRasMessage_gatekeeperConfirm:
1667                 return process_gcf(skb, ct, ctinfo, data,
1668                                    &ras->gatekeeperConfirm);
1669         case eRasMessage_registrationRequest:
1670                 return process_rrq(skb, ct, ctinfo, data,
1671                                    &ras->registrationRequest);
1672         case eRasMessage_registrationConfirm:
1673                 return process_rcf(skb, ct, ctinfo, data,
1674                                    &ras->registrationConfirm);
1675         case eRasMessage_unregistrationRequest:
1676                 return process_urq(skb, ct, ctinfo, data,
1677                                    &ras->unregistrationRequest);
1678         case eRasMessage_admissionRequest:
1679                 return process_arq(skb, ct, ctinfo, data,
1680                                    &ras->admissionRequest);
1681         case eRasMessage_admissionConfirm:
1682                 return process_acf(skb, ct, ctinfo, data,
1683                                    &ras->admissionConfirm);
1684         case eRasMessage_locationRequest:
1685                 return process_lrq(skb, ct, ctinfo, data,
1686                                    &ras->locationRequest);
1687         case eRasMessage_locationConfirm:
1688                 return process_lcf(skb, ct, ctinfo, data,
1689                                    &ras->locationConfirm);
1690         case eRasMessage_infoRequestResponse:
1691                 return process_irr(skb, ct, ctinfo, data,
1692                                    &ras->infoRequestResponse);
1693         default:
1694                 pr_debug("nf_ct_ras: RAS message %d\n", ras->choice);
1695                 break;
1696         }
1697
1698         return 0;
1699 }
1700
1701 /****************************************************************************/
1702 static int ras_help(struct sk_buff *skb, unsigned int protoff,
1703                     struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1704 {
1705         static RasMessage ras;
1706         unsigned char *data;
1707         int datalen = 0;
1708         int ret;
1709
1710         pr_debug("nf_ct_ras: skblen = %u\n", skb->len);
1711
1712         spin_lock_bh(&nf_h323_lock);
1713
1714         /* Get UDP data */
1715         data = get_udp_data(skb, protoff, &datalen);
1716         if (data == NULL)
1717                 goto accept;
1718         pr_debug("nf_ct_ras: RAS message len=%d ", datalen);
1719         NF_CT_DUMP_TUPLE(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1720
1721         /* Decode RAS message */
1722         ret = DecodeRasMessage(data, datalen, &ras);
1723         if (ret < 0) {
1724                 pr_debug("nf_ct_ras: decoding error: %s\n",
1725                          ret == H323_ERROR_BOUND ?
1726                          "out of bound" : "out of range");
1727                 goto accept;
1728         }
1729
1730         /* Process RAS message */
1731         if (process_ras(skb, ct, ctinfo, &data, &ras) < 0)
1732                 goto drop;
1733
1734       accept:
1735         spin_unlock_bh(&nf_h323_lock);
1736         return NF_ACCEPT;
1737
1738       drop:
1739         spin_unlock_bh(&nf_h323_lock);
1740         if (net_ratelimit())
1741                 printk("nf_ct_ras: packet dropped\n");
1742         return NF_DROP;
1743 }
1744
1745 /****************************************************************************/
1746 static const struct nf_conntrack_expect_policy ras_exp_policy = {
1747         .max_expected           = 32,
1748         .timeout                = 240,
1749 };
1750
1751 static struct nf_conntrack_helper nf_conntrack_helper_ras[] __read_mostly = {
1752         {
1753                 .name                   = "RAS",
1754                 .me                     = THIS_MODULE,
1755                 .tuple.src.l3num        = AF_INET,
1756                 .tuple.src.u.udp.port   = __constant_htons(RAS_PORT),
1757                 .tuple.dst.protonum     = IPPROTO_UDP,
1758                 .help                   = ras_help,
1759                 .expect_policy          = &ras_exp_policy,
1760         },
1761         {
1762                 .name                   = "RAS",
1763                 .me                     = THIS_MODULE,
1764                 .tuple.src.l3num        = AF_INET6,
1765                 .tuple.src.u.udp.port   = __constant_htons(RAS_PORT),
1766                 .tuple.dst.protonum     = IPPROTO_UDP,
1767                 .help                   = ras_help,
1768                 .expect_policy          = &ras_exp_policy,
1769         },
1770 };
1771
1772 /****************************************************************************/
1773 static void __exit nf_conntrack_h323_fini(void)
1774 {
1775         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[1]);
1776         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1777         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1778         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1779         kfree(h323_buffer);
1780         pr_debug("nf_ct_h323: fini\n");
1781 }
1782
1783 /****************************************************************************/
1784 static int __init nf_conntrack_h323_init(void)
1785 {
1786         int ret;
1787
1788         h323_buffer = kmalloc(65536, GFP_KERNEL);
1789         if (!h323_buffer)
1790                 return -ENOMEM;
1791         ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[0]);
1792         if (ret < 0)
1793                 goto err1;
1794         ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[1]);
1795         if (ret < 0)
1796                 goto err2;
1797         ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[0]);
1798         if (ret < 0)
1799                 goto err3;
1800         ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[1]);
1801         if (ret < 0)
1802                 goto err4;
1803         pr_debug("nf_ct_h323: init success\n");
1804         return 0;
1805
1806 err4:
1807         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1808 err3:
1809         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1810 err2:
1811         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1812 err1:
1813         return ret;
1814 }
1815
1816 /****************************************************************************/
1817 module_init(nf_conntrack_h323_init);
1818 module_exit(nf_conntrack_h323_fini);
1819
1820 EXPORT_SYMBOL_GPL(get_h225_addr);
1821 EXPORT_SYMBOL_GPL(set_h245_addr_hook);
1822 EXPORT_SYMBOL_GPL(set_h225_addr_hook);
1823 EXPORT_SYMBOL_GPL(set_sig_addr_hook);
1824 EXPORT_SYMBOL_GPL(set_ras_addr_hook);
1825 EXPORT_SYMBOL_GPL(nat_rtp_rtcp_hook);
1826 EXPORT_SYMBOL_GPL(nat_t120_hook);
1827 EXPORT_SYMBOL_GPL(nat_h245_hook);
1828 EXPORT_SYMBOL_GPL(nat_callforwarding_hook);
1829 EXPORT_SYMBOL_GPL(nat_q931_hook);
1830
1831 MODULE_AUTHOR("Jing Min Zhao <zhaojingmin@users.sourceforge.net>");
1832 MODULE_DESCRIPTION("H.323 connection tracking helper");
1833 MODULE_LICENSE("GPL");
1834 MODULE_ALIAS("ip_conntrack_h323");