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 len;
 222
 223         if (taddr->choice != eH245_TransportAddress_unicastAddress)
 224                 return 0;
 225
 226         switch (taddr->unicastAddress.choice) {
 227         case eUnicastAddress_iPAddress:
 228                 if (nf_ct_l3num(ct) != AF_INET)
 229                         return 0;
 230                 p = data + taddr->unicastAddress.iPAddress.network;
 231                 len = 4;
 232                 break;
 233         case eUnicastAddress_iP6Address:
 234                 if (nf_ct_l3num(ct) != AF_INET6)
 235                         return 0;
 236                 p = data + taddr->unicastAddress.iP6Address.network;
 237                 len = 16;
 238                 break;
 239         default:
 240                 return 0;
 241         }
 242
 243         memcpy(addr, p, len);
 244         memset((void *)addr + len, 0, sizeof(*addr) - len);
 245         memcpy(port, p + len, sizeof(__be16));
 246
 247         return 1;
 248 }
 249
 250 /****************************************************************************/
 251 static int expect_rtp_rtcp(struct sk_buff *skb, struct nf_conn *ct,
 252                            enum ip_conntrack_info ctinfo,
 253                            unsigned char **data, int dataoff,
 254                            H245_TransportAddress *taddr)
 255 {
 256         int dir = CTINFO2DIR(ctinfo);
 257         int ret = 0;
 258         __be16 port;
 259         __be16 rtp_port, rtcp_port;
 260         union nf_inet_addr addr;
 261         struct nf_conntrack_expect *rtp_exp;
 262         struct nf_conntrack_expect *rtcp_exp;
 263         typeof(nat_rtp_rtcp_hook) nat_rtp_rtcp;
 264
 265         /* Read RTP or RTCP address */
 266         if (!get_h245_addr(ct, *data, taddr, &addr, &port) ||
 267             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
 268             port == 0)
 269                 return 0;
 270
 271         /* RTP port is even */
 272         port &= htons(~1);
 273         rtp_port = port;
 274         rtcp_port = htons(ntohs(port) + 1);
 275
 276         /* Create expect for RTP */
 277         if ((rtp_exp = nf_ct_expect_alloc(ct)) == NULL)
 278                 return -1;
 279         nf_ct_expect_init(rtp_exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 280                           &ct->tuplehash[!dir].tuple.src.u3,
 281                           &ct->tuplehash[!dir].tuple.dst.u3,
 282                           IPPROTO_UDP, NULL, &rtp_port);
 283
 284         /* Create expect for RTCP */
 285         if ((rtcp_exp = nf_ct_expect_alloc(ct)) == NULL) {
 286                 nf_ct_expect_put(rtp_exp);
 287                 return -1;
 288         }
 289         nf_ct_expect_init(rtcp_exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 290                           &ct->tuplehash[!dir].tuple.src.u3,
 291                           &ct->tuplehash[!dir].tuple.dst.u3,
 292                           IPPROTO_UDP, NULL, &rtcp_port);
 293
 294         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 295                    &ct->tuplehash[!dir].tuple.dst.u3,
 296                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 297                    (nat_rtp_rtcp = rcu_dereference(nat_rtp_rtcp_hook)) &&
 298                    ct->status & IPS_NAT_MASK) {
 299                 /* NAT needed */
 300                 ret = nat_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
 301                                    taddr, port, rtp_port, rtp_exp, rtcp_exp);
 302         } else {                /* Conntrack only */
 303                 if (nf_ct_expect_related(rtp_exp) == 0) {
 304                         if (nf_ct_expect_related(rtcp_exp) == 0) {
 305                                 pr_debug("nf_ct_h323: expect RTP ");
 306                                 nf_ct_dump_tuple(&rtp_exp->tuple);
 307                                 pr_debug("nf_ct_h323: expect RTCP ");
 308                                 nf_ct_dump_tuple(&rtcp_exp->tuple);
 309                         } else {
 310                                 nf_ct_unexpect_related(rtp_exp);
 311                                 ret = -1;
 312                         }
 313                 } else
 314                         ret = -1;
 315         }
 316
 317         nf_ct_expect_put(rtp_exp);
 318         nf_ct_expect_put(rtcp_exp);
 319
 320         return ret;
 321 }
 322
 323 /****************************************************************************/
 324 static int expect_t120(struct sk_buff *skb,
 325                        struct nf_conn *ct,
 326                        enum ip_conntrack_info ctinfo,
 327                        unsigned char **data, int dataoff,
 328                        H245_TransportAddress *taddr)
 329 {
 330         int dir = CTINFO2DIR(ctinfo);
 331         int ret = 0;
 332         __be16 port;
 333         union nf_inet_addr addr;
 334         struct nf_conntrack_expect *exp;
 335         typeof(nat_t120_hook) nat_t120;
 336
 337         /* Read T.120 address */
 338         if (!get_h245_addr(ct, *data, taddr, &addr, &port) ||
 339             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
 340             port == 0)
 341                 return 0;
 342
 343         /* Create expect for T.120 connections */
 344         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
 345                 return -1;
 346         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 347                           &ct->tuplehash[!dir].tuple.src.u3,
 348                           &ct->tuplehash[!dir].tuple.dst.u3,
 349                           IPPROTO_TCP, NULL, &port);
 350         exp->flags = NF_CT_EXPECT_PERMANENT;    /* Accept multiple channels */
 351
 352         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 353                    &ct->tuplehash[!dir].tuple.dst.u3,
 354                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 355             (nat_t120 = rcu_dereference(nat_t120_hook)) &&
 356             ct->status & IPS_NAT_MASK) {
 357                 /* NAT needed */
 358                 ret = nat_t120(skb, ct, ctinfo, data, dataoff, taddr,
 359                                port, exp);
 360         } else {                /* Conntrack only */
 361                 if (nf_ct_expect_related(exp) == 0) {
 362                         pr_debug("nf_ct_h323: expect T.120 ");
 363                         nf_ct_dump_tuple(&exp->tuple);
 364                 } else
 365                         ret = -1;
 366         }
 367
 368         nf_ct_expect_put(exp);
 369
 370         return ret;
 371 }
 372
 373 /****************************************************************************/
 374 static int process_h245_channel(struct sk_buff *skb,
 375                                 struct nf_conn *ct,
 376                                 enum ip_conntrack_info ctinfo,
 377                                 unsigned char **data, int dataoff,
 378                                 H2250LogicalChannelParameters *channel)
 379 {
 380         int ret;
 381
 382         if (channel->options & eH2250LogicalChannelParameters_mediaChannel) {
 383                 /* RTP */
 384                 ret = expect_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
 385                                       &channel->mediaChannel);
 386                 if (ret < 0)
 387                         return -1;
 388         }
 389
 390         if (channel->
 391             options & eH2250LogicalChannelParameters_mediaControlChannel) {
 392                 /* RTCP */
 393                 ret = expect_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
 394                                       &channel->mediaControlChannel);
 395                 if (ret < 0)
 396                         return -1;
 397         }
 398
 399         return 0;
 400 }
 401
 402 /****************************************************************************/
 403 static int process_olc(struct sk_buff *skb, struct nf_conn *ct,
 404                        enum ip_conntrack_info ctinfo,
 405                        unsigned char **data, int dataoff,
 406                        OpenLogicalChannel *olc)
 407 {
 408         int ret;
 409
 410         pr_debug("nf_ct_h323: OpenLogicalChannel\n");
 411
 412         if (olc->forwardLogicalChannelParameters.multiplexParameters.choice ==
 413             eOpenLogicalChannel_forwardLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters)
 414         {
 415                 ret = process_h245_channel(skb, ct, ctinfo, data, dataoff,
 416                                            &olc->
 417                                            forwardLogicalChannelParameters.
 418                                            multiplexParameters.
 419                                            h2250LogicalChannelParameters);
 420                 if (ret < 0)
 421                         return -1;
 422         }
 423
 424         if ((olc->options &
 425              eOpenLogicalChannel_reverseLogicalChannelParameters) &&
 426             (olc->reverseLogicalChannelParameters.options &
 427              eOpenLogicalChannel_reverseLogicalChannelParameters_multiplexParameters)
 428             && (olc->reverseLogicalChannelParameters.multiplexParameters.
 429                 choice ==
 430                 eOpenLogicalChannel_reverseLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters))
 431         {
 432                 ret =
 433                     process_h245_channel(skb, ct, ctinfo, data, dataoff,
 434                                          &olc->
 435                                          reverseLogicalChannelParameters.
 436                                          multiplexParameters.
 437                                          h2250LogicalChannelParameters);
 438                 if (ret < 0)
 439                         return -1;
 440         }
 441
 442         if ((olc->options & eOpenLogicalChannel_separateStack) &&
 443             olc->forwardLogicalChannelParameters.dataType.choice ==
 444             eDataType_data &&
 445             olc->forwardLogicalChannelParameters.dataType.data.application.
 446             choice == eDataApplicationCapability_application_t120 &&
 447             olc->forwardLogicalChannelParameters.dataType.data.application.
 448             t120.choice == eDataProtocolCapability_separateLANStack &&
 449             olc->separateStack.networkAddress.choice ==
 450             eNetworkAccessParameters_networkAddress_localAreaAddress) {
 451                 ret = expect_t120(skb, ct, ctinfo, data, dataoff,
 452                                   &olc->separateStack.networkAddress.
 453                                   localAreaAddress);
 454                 if (ret < 0)
 455                         return -1;
 456         }
 457
 458         return 0;
 459 }
 460
 461 /****************************************************************************/
 462 static int process_olca(struct sk_buff *skb, struct nf_conn *ct,
 463                         enum ip_conntrack_info ctinfo,
 464                         unsigned char **data, int dataoff,
 465                         OpenLogicalChannelAck *olca)
 466 {
 467         H2250LogicalChannelAckParameters *ack;
 468         int ret;
 469
 470         pr_debug("nf_ct_h323: OpenLogicalChannelAck\n");
 471
 472         if ((olca->options &
 473              eOpenLogicalChannelAck_reverseLogicalChannelParameters) &&
 474             (olca->reverseLogicalChannelParameters.options &
 475              eOpenLogicalChannelAck_reverseLogicalChannelParameters_multiplexParameters)
 476             && (olca->reverseLogicalChannelParameters.multiplexParameters.
 477                 choice ==
 478                 eOpenLogicalChannelAck_reverseLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters))
 479         {
 480                 ret = process_h245_channel(skb, ct, ctinfo, data, dataoff,
 481                                            &olca->
 482                                            reverseLogicalChannelParameters.
 483                                            multiplexParameters.
 484                                            h2250LogicalChannelParameters);
 485                 if (ret < 0)
 486                         return -1;
 487         }
 488
 489         if ((olca->options &
 490              eOpenLogicalChannelAck_forwardMultiplexAckParameters) &&
 491             (olca->forwardMultiplexAckParameters.choice ==
 492              eOpenLogicalChannelAck_forwardMultiplexAckParameters_h2250LogicalChannelAckParameters))
 493         {
 494                 ack = &olca->forwardMultiplexAckParameters.
 495                     h2250LogicalChannelAckParameters;
 496                 if (ack->options &
 497                     eH2250LogicalChannelAckParameters_mediaChannel) {
 498                         /* RTP */
 499                         ret = expect_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
 500                                               &ack->mediaChannel);
 501                         if (ret < 0)
 502                                 return -1;
 503                 }
 504
 505                 if (ack->options &
 506                     eH2250LogicalChannelAckParameters_mediaControlChannel) {
 507                         /* RTCP */
 508                         ret = expect_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
 509                                               &ack->mediaControlChannel);
 510                         if (ret < 0)
 511                                 return -1;
 512                 }
 513         }
 514
 515         if ((olca->options & eOpenLogicalChannelAck_separateStack) &&
 516                 olca->separateStack.networkAddress.choice ==
 517                 eNetworkAccessParameters_networkAddress_localAreaAddress) {
 518                 ret = expect_t120(skb, ct, ctinfo, data, dataoff,
 519                                   &olca->separateStack.networkAddress.
 520                                   localAreaAddress);
 521                 if (ret < 0)
 522                         return -1;
 523         }
 524
 525         return 0;
 526 }
 527
 528 /****************************************************************************/
 529 static int process_h245(struct sk_buff *skb, struct nf_conn *ct,
 530                         enum ip_conntrack_info ctinfo,
 531                         unsigned char **data, int dataoff,
 532                         MultimediaSystemControlMessage *mscm)
 533 {
 534         switch (mscm->choice) {
 535         case eMultimediaSystemControlMessage_request:
 536                 if (mscm->request.choice ==
 537                     eRequestMessage_openLogicalChannel) {
 538                         return process_olc(skb, ct, ctinfo, data, dataoff,
 539                                            &mscm->request.openLogicalChannel);
 540                 }
 541                 pr_debug("nf_ct_h323: H.245 Request %d\n",
 542                          mscm->request.choice);
 543                 break;
 544         case eMultimediaSystemControlMessage_response:
 545                 if (mscm->response.choice ==
 546                     eResponseMessage_openLogicalChannelAck) {
 547                         return process_olca(skb, ct, ctinfo, data, dataoff,
 548                                             &mscm->response.
 549                                             openLogicalChannelAck);
 550                 }
 551                 pr_debug("nf_ct_h323: H.245 Response %d\n",
 552                          mscm->response.choice);
 553                 break;
 554         default:
 555                 pr_debug("nf_ct_h323: H.245 signal %d\n", mscm->choice);
 556                 break;
 557         }
 558
 559         return 0;
 560 }
 561
 562 /****************************************************************************/
 563 static int h245_help(struct sk_buff *skb, unsigned int protoff,
 564                      struct nf_conn *ct, enum ip_conntrack_info ctinfo)
 565 {
 566         static MultimediaSystemControlMessage mscm;
 567         unsigned char *data = NULL;
 568         int datalen;
 569         int dataoff;
 570         int ret;
 571
 572         /* Until there's been traffic both ways, don't look in packets. */
 573         if (ctinfo != IP_CT_ESTABLISHED &&
 574             ctinfo != IP_CT_ESTABLISHED + IP_CT_IS_REPLY) {
 575                 return NF_ACCEPT;
 576         }
 577         pr_debug("nf_ct_h245: skblen = %u\n", skb->len);
 578
 579         spin_lock_bh(&nf_h323_lock);
 580
 581         /* Process each TPKT */
 582         while (get_tpkt_data(skb, protoff, ct, ctinfo,
 583                              &data, &datalen, &dataoff)) {
 584                 pr_debug("nf_ct_h245: TPKT len=%d ", datalen);
 585                 nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
 586
 587                 /* Decode H.245 signal */
 588                 ret = DecodeMultimediaSystemControlMessage(data, datalen,
 589                                                            &mscm);
 590                 if (ret < 0) {
 591                         pr_debug("nf_ct_h245: decoding error: %s\n",
 592                                  ret == H323_ERROR_BOUND ?
 593                                  "out of bound" : "out of range");
 594                         /* We don't drop when decoding error */
 595                         break;
 596                 }
 597
 598                 /* Process H.245 signal */
 599                 if (process_h245(skb, ct, ctinfo, &data, dataoff, &mscm) < 0)
 600                         goto drop;
 601         }
 602
 603         spin_unlock_bh(&nf_h323_lock);
 604         return NF_ACCEPT;
 605
 606       drop:
 607         spin_unlock_bh(&nf_h323_lock);
 608         if (net_ratelimit())
 609                 printk("nf_ct_h245: packet dropped\n");
 610         return NF_DROP;
 611 }
 612
 613 /****************************************************************************/
 614 static const struct nf_conntrack_expect_policy h245_exp_policy = {
 615         .max_expected   = H323_RTP_CHANNEL_MAX * 4 + 2 /* T.120 */,
 616         .timeout        = 240,
 617 };
 618
 619 static struct nf_conntrack_helper nf_conntrack_helper_h245 __read_mostly = {
 620         .name                   = "H.245",
 621         .me                     = THIS_MODULE,
 622         .tuple.src.l3num        = AF_UNSPEC,
 623         .tuple.dst.protonum     = IPPROTO_UDP,
 624         .help                   = h245_help,
 625         .expect_policy          = &h245_exp_policy,
 626 };
 627
 628 /****************************************************************************/
 629 int get_h225_addr(struct nf_conn *ct, unsigned char *data,
 630                   TransportAddress *taddr,
 631                   union nf_inet_addr *addr, __be16 *port)
 632 {
 633         const unsigned char *p;
 634         int len;
 635
 636         switch (taddr->choice) {
 637         case eTransportAddress_ipAddress:
 638                 if (nf_ct_l3num(ct) != AF_INET)
 639                         return 0;
 640                 p = data + taddr->ipAddress.ip;
 641                 len = 4;
 642                 break;
 643         case eTransportAddress_ip6Address:
 644                 if (nf_ct_l3num(ct) != AF_INET6)
 645                         return 0;
 646                 p = data + taddr->ip6Address.ip;
 647                 len = 16;
 648                 break;
 649         default:
 650                 return 0;
 651         }
 652
 653         memcpy(addr, p, len);
 654         memset((void *)addr + len, 0, sizeof(*addr) - len);
 655         memcpy(port, p + len, sizeof(__be16));
 656
 657         return 1;
 658 }
 659
 660 /****************************************************************************/
 661 static int expect_h245(struct sk_buff *skb, struct nf_conn *ct,
 662                        enum ip_conntrack_info ctinfo,
 663                        unsigned char **data, int dataoff,
 664                        TransportAddress *taddr)
 665 {
 666         int dir = CTINFO2DIR(ctinfo);
 667         int ret = 0;
 668         __be16 port;
 669         union nf_inet_addr addr;
 670         struct nf_conntrack_expect *exp;
 671         typeof(nat_h245_hook) nat_h245;
 672
 673         /* Read h245Address */
 674         if (!get_h225_addr(ct, *data, taddr, &addr, &port) ||
 675             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
 676             port == 0)
 677                 return 0;
 678
 679         /* Create expect for h245 connection */
 680         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
 681                 return -1;
 682         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 683                           &ct->tuplehash[!dir].tuple.src.u3,
 684                           &ct->tuplehash[!dir].tuple.dst.u3,
 685                           IPPROTO_TCP, NULL, &port);
 686         exp->helper = &nf_conntrack_helper_h245;
 687
 688         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 689                    &ct->tuplehash[!dir].tuple.dst.u3,
 690                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 691             (nat_h245 = rcu_dereference(nat_h245_hook)) &&
 692             ct->status & IPS_NAT_MASK) {
 693                 /* NAT needed */
 694                 ret = nat_h245(skb, ct, ctinfo, data, dataoff, taddr,
 695                                port, exp);
 696         } else {                /* Conntrack only */
 697                 if (nf_ct_expect_related(exp) == 0) {
 698                         pr_debug("nf_ct_q931: expect H.245 ");
 699                         nf_ct_dump_tuple(&exp->tuple);
 700                 } else
 701                         ret = -1;
 702         }
 703
 704         nf_ct_expect_put(exp);
 705
 706         return ret;
 707 }
 708
 709 /* If the calling party is on the same side of the forward-to party,
 710  * we don't need to track the second call */
 711 static int callforward_do_filter(const union nf_inet_addr *src,
 712                                  const union nf_inet_addr *dst,
 713                                  u_int8_t family)
 714 {
 715         const struct nf_afinfo *afinfo;
 716         struct flowi fl1, fl2;
 717         int ret = 0;
 718
 719         /* rcu_read_lock()ed by nf_hook_slow() */
 720         afinfo = nf_get_afinfo(family);
 721         if (!afinfo)
 722                 return 0;
 723
 724         memset(&fl1, 0, sizeof(fl1));
 725         memset(&fl2, 0, sizeof(fl2));
 726
 727         switch (family) {
 728         case AF_INET: {
 729                 struct rtable *rt1, *rt2;
 730
 731                 fl1.fl4_dst = src->ip;
 732                 fl2.fl4_dst = dst->ip;
 733                 if (!afinfo->route((struct dst_entry **)&rt1, &fl1)) {
 734                         if (!afinfo->route((struct dst_entry **)&rt2, &fl2)) {
 735                                 if (rt1->rt_gateway == rt2->rt_gateway &&
 736                                     rt1->u.dst.dev  == rt2->u.dst.dev)
 737                                         ret = 1;
 738                                 dst_release(&rt2->u.dst);
 739                         }
 740                         dst_release(&rt1->u.dst);
 741                 }
 742                 break;
 743         }
 744 #if defined(CONFIG_NF_CONNTRACK_IPV6) || \
 745     defined(CONFIG_NF_CONNTRACK_IPV6_MODULE)
 746         case AF_INET6: {
 747                 struct rt6_info *rt1, *rt2;
 748
 749                 memcpy(&fl1.fl6_dst, src, sizeof(fl1.fl6_dst));
 750                 memcpy(&fl2.fl6_dst, dst, sizeof(fl2.fl6_dst));
 751                 if (!afinfo->route((struct dst_entry **)&rt1, &fl1)) {
 752                         if (!afinfo->route((struct dst_entry **)&rt2, &fl2)) {
 753                                 if (!memcmp(&rt1->rt6i_gateway, &rt2->rt6i_gateway,
 754                                             sizeof(rt1->rt6i_gateway)) &&
 755                                     rt1->u.dst.dev == rt2->u.dst.dev)
 756                                         ret = 1;
 757                                 dst_release(&rt2->u.dst);
 758                         }
 759                         dst_release(&rt1->u.dst);
 760                 }
 761                 break;
 762         }
 763 #endif
 764         }
 765         return ret;
 766
 767 }
 768
 769 /****************************************************************************/
 770 static int expect_callforwarding(struct sk_buff *skb,
 771                                  struct nf_conn *ct,
 772                                  enum ip_conntrack_info ctinfo,
 773                                  unsigned char **data, int dataoff,
 774                                  TransportAddress *taddr)
 775 {
 776         int dir = CTINFO2DIR(ctinfo);
 777         int ret = 0;
 778         __be16 port;
 779         union nf_inet_addr addr;
 780         struct nf_conntrack_expect *exp;
 781         typeof(nat_callforwarding_hook) nat_callforwarding;
 782
 783         /* Read alternativeAddress */
 784         if (!get_h225_addr(ct, *data, taddr, &addr, &port) || port == 0)
 785                 return 0;
 786
 787         /* If the calling party is on the same side of the forward-to party,
 788          * we don't need to track the second call */
 789         if (callforward_filter &&
 790             callforward_do_filter(&addr, &ct->tuplehash[!dir].tuple.src.u3,
 791                                   nf_ct_l3num(ct))) {
 792                 pr_debug("nf_ct_q931: Call Forwarding not tracked\n");
 793                 return 0;
 794         }
 795
 796         /* Create expect for the second call leg */
 797         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
 798                 return -1;
 799         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 800                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
 801                           IPPROTO_TCP, NULL, &port);
 802         exp->helper = nf_conntrack_helper_q931;
 803
 804         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 805                    &ct->tuplehash[!dir].tuple.dst.u3,
 806                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 807             (nat_callforwarding = rcu_dereference(nat_callforwarding_hook)) &&
 808             ct->status & IPS_NAT_MASK) {
 809                 /* Need NAT */
 810                 ret = nat_callforwarding(skb, ct, ctinfo, data, dataoff,
 811                                          taddr, port, exp);
 812         } else {                /* Conntrack only */
 813                 if (nf_ct_expect_related(exp) == 0) {
 814                         pr_debug("nf_ct_q931: expect Call Forwarding ");
 815                         nf_ct_dump_tuple(&exp->tuple);
 816                 } else
 817                         ret = -1;
 818         }
 819
 820         nf_ct_expect_put(exp);
 821
 822         return ret;
 823 }
 824
 825 /****************************************************************************/
 826 static int process_setup(struct sk_buff *skb, struct nf_conn *ct,
 827                          enum ip_conntrack_info ctinfo,
 828                          unsigned char **data, int dataoff,
 829                          Setup_UUIE *setup)
 830 {
 831         int dir = CTINFO2DIR(ctinfo);
 832         int ret;
 833         int i;
 834         __be16 port;
 835         union nf_inet_addr addr;
 836         typeof(set_h225_addr_hook) set_h225_addr;
 837
 838         pr_debug("nf_ct_q931: Setup\n");
 839
 840         if (setup->options & eSetup_UUIE_h245Address) {
 841                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
 842                                   &setup->h245Address);
 843                 if (ret < 0)
 844                         return -1;
 845         }
 846
 847         set_h225_addr = rcu_dereference(set_h225_addr_hook);
 848         if ((setup->options & eSetup_UUIE_destCallSignalAddress) &&
 849             (set_h225_addr) && ct->status & IPS_NAT_MASK &&
 850             get_h225_addr(ct, *data, &setup->destCallSignalAddress,
 851                           &addr, &port) &&
 852             memcmp(&addr, &ct->tuplehash[!dir].tuple.src.u3, sizeof(addr))) {
 853                 pr_debug("nf_ct_q931: set destCallSignalAddress "
 854                          NIP6_FMT ":%hu->" NIP6_FMT ":%hu\n",
 855                          NIP6(*(struct in6_addr *)&addr), ntohs(port),
 856                          NIP6(*(struct in6_addr *)&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 "
 872                          NIP6_FMT ":%hu->" NIP6_FMT ":%hu\n",
 873                          NIP6(*(struct in6_addr *)&addr), ntohs(port),
 874                          NIP6(*(struct in6_addr *)&ct->tuplehash[!dir].tuple.dst.u3),
 875                          ntohs(ct->tuplehash[!dir].tuple.dst.u.tcp.port));
 876                 ret = set_h225_addr(skb, data, dataoff,
 877                                     &setup->sourceCallSignalAddress,
 878                                     &ct->tuplehash[!dir].tuple.dst.u3,
 879                                     ct->tuplehash[!dir].tuple.dst.u.tcp.port);
 880                 if (ret < 0)
 881                         return -1;
 882         }
 883
 884         if (setup->options & eSetup_UUIE_fastStart) {
 885                 for (i = 0; i < setup->fastStart.count; i++) {
 886                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
 887                                           &setup->fastStart.item[i]);
 888                         if (ret < 0)
 889                                 return -1;
 890                 }
 891         }
 892
 893         return 0;
 894 }
 895
 896 /****************************************************************************/
 897 static int process_callproceeding(struct sk_buff *skb,
 898                                   struct nf_conn *ct,
 899                                   enum ip_conntrack_info ctinfo,
 900                                   unsigned char **data, int dataoff,
 901                                   CallProceeding_UUIE *callproc)
 902 {
 903         int ret;
 904         int i;
 905
 906         pr_debug("nf_ct_q931: CallProceeding\n");
 907
 908         if (callproc->options & eCallProceeding_UUIE_h245Address) {
 909                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
 910                                   &callproc->h245Address);
 911                 if (ret < 0)
 912                         return -1;
 913         }
 914
 915         if (callproc->options & eCallProceeding_UUIE_fastStart) {
 916                 for (i = 0; i < callproc->fastStart.count; i++) {
 917                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
 918                                           &callproc->fastStart.item[i]);
 919                         if (ret < 0)
 920                                 return -1;
 921                 }
 922         }
 923
 924         return 0;
 925 }
 926
 927 /****************************************************************************/
 928 static int process_connect(struct sk_buff *skb, struct nf_conn *ct,
 929                            enum ip_conntrack_info ctinfo,
 930                            unsigned char **data, int dataoff,
 931                            Connect_UUIE *connect)
 932 {
 933         int ret;
 934         int i;
 935
 936         pr_debug("nf_ct_q931: Connect\n");
 937
 938         if (connect->options & eConnect_UUIE_h245Address) {
 939                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
 940                                   &connect->h245Address);
 941                 if (ret < 0)
 942                         return -1;
 943         }
 944
 945         if (connect->options & eConnect_UUIE_fastStart) {
 946                 for (i = 0; i < connect->fastStart.count; i++) {
 947                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
 948                                           &connect->fastStart.item[i]);
 949                         if (ret < 0)
 950                                 return -1;
 951                 }
 952         }
 953
 954         return 0;
 955 }
 956
 957 /****************************************************************************/
 958 static int process_alerting(struct sk_buff *skb, struct nf_conn *ct,
 959                             enum ip_conntrack_info ctinfo,
 960                             unsigned char **data, int dataoff,
 961                             Alerting_UUIE *alert)
 962 {
 963         int ret;
 964         int i;
 965
 966         pr_debug("nf_ct_q931: Alerting\n");
 967
 968         if (alert->options & eAlerting_UUIE_h245Address) {
 969                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
 970                                   &alert->h245Address);
 971                 if (ret < 0)
 972                         return -1;
 973         }
 974
 975         if (alert->options & eAlerting_UUIE_fastStart) {
 976                 for (i = 0; i < alert->fastStart.count; i++) {
 977                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
 978                                           &alert->fastStart.item[i]);
 979                         if (ret < 0)
 980                                 return -1;
 981                 }
 982         }
 983
 984         return 0;
 985 }
 986
 987 /****************************************************************************/
 988 static int process_facility(struct sk_buff *skb, struct nf_conn *ct,
 989                             enum ip_conntrack_info ctinfo,
 990                             unsigned char **data, int dataoff,
 991                             Facility_UUIE *facility)
 992 {
 993         int ret;
 994         int i;
 995
 996         pr_debug("nf_ct_q931: Facility\n");
 997
 998         if (facility->reason.choice == eFacilityReason_callForwarded) {
 999                 if (facility->options & eFacility_UUIE_alternativeAddress)
1000                         return expect_callforwarding(skb, ct, ctinfo, data,
1001                                                      dataoff,
1002                                                      &facility->
1003                                                      alternativeAddress);
1004                 return 0;
1005         }
1006
1007         if (facility->options & eFacility_UUIE_h245Address) {
1008                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
1009                                   &facility->h245Address);
1010                 if (ret < 0)
1011                         return -1;
1012         }
1013
1014         if (facility->options & eFacility_UUIE_fastStart) {
1015                 for (i = 0; i < facility->fastStart.count; i++) {
1016                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
1017                                           &facility->fastStart.item[i]);
1018                         if (ret < 0)
1019                                 return -1;
1020                 }
1021         }
1022
1023         return 0;
1024 }
1025
1026 /****************************************************************************/
1027 static int process_progress(struct sk_buff *skb, struct nf_conn *ct,
1028                             enum ip_conntrack_info ctinfo,
1029                             unsigned char **data, int dataoff,
1030                             Progress_UUIE *progress)
1031 {
1032         int ret;
1033         int i;
1034
1035         pr_debug("nf_ct_q931: Progress\n");
1036
1037         if (progress->options & eProgress_UUIE_h245Address) {
1038                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
1039                                   &progress->h245Address);
1040                 if (ret < 0)
1041                         return -1;
1042         }
1043
1044         if (progress->options & eProgress_UUIE_fastStart) {
1045                 for (i = 0; i < progress->fastStart.count; i++) {
1046                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
1047                                           &progress->fastStart.item[i]);
1048                         if (ret < 0)
1049                                 return -1;
1050                 }
1051         }
1052
1053         return 0;
1054 }
1055
1056 /****************************************************************************/
1057 static int process_q931(struct sk_buff *skb, struct nf_conn *ct,
1058                         enum ip_conntrack_info ctinfo,
1059                         unsigned char **data, int dataoff, Q931 *q931)
1060 {
1061         H323_UU_PDU *pdu = &q931->UUIE.h323_uu_pdu;
1062         int i;
1063         int ret = 0;
1064
1065         switch (pdu->h323_message_body.choice) {
1066         case eH323_UU_PDU_h323_message_body_setup:
1067                 ret = process_setup(skb, ct, ctinfo, data, dataoff,
1068                                     &pdu->h323_message_body.setup);
1069                 break;
1070         case eH323_UU_PDU_h323_message_body_callProceeding:
1071                 ret = process_callproceeding(skb, ct, ctinfo, data, dataoff,
1072                                              &pdu->h323_message_body.
1073                                              callProceeding);
1074                 break;
1075         case eH323_UU_PDU_h323_message_body_connect:
1076                 ret = process_connect(skb, ct, ctinfo, data, dataoff,
1077                                       &pdu->h323_message_body.connect);
1078                 break;
1079         case eH323_UU_PDU_h323_message_body_alerting:
1080                 ret = process_alerting(skb, ct, ctinfo, data, dataoff,
1081                                        &pdu->h323_message_body.alerting);
1082                 break;
1083         case eH323_UU_PDU_h323_message_body_facility:
1084                 ret = process_facility(skb, ct, ctinfo, data, dataoff,
1085                                        &pdu->h323_message_body.facility);
1086                 break;
1087         case eH323_UU_PDU_h323_message_body_progress:
1088                 ret = process_progress(skb, ct, ctinfo, data, dataoff,
1089                                        &pdu->h323_message_body.progress);
1090                 break;
1091         default:
1092                 pr_debug("nf_ct_q931: Q.931 signal %d\n",
1093                          pdu->h323_message_body.choice);
1094                 break;
1095         }
1096
1097         if (ret < 0)
1098                 return -1;
1099
1100         if (pdu->options & eH323_UU_PDU_h245Control) {
1101                 for (i = 0; i < pdu->h245Control.count; i++) {
1102                         ret = process_h245(skb, ct, ctinfo, data, dataoff,
1103                                            &pdu->h245Control.item[i]);
1104                         if (ret < 0)
1105                                 return -1;
1106                 }
1107         }
1108
1109         return 0;
1110 }
1111
1112 /****************************************************************************/
1113 static int q931_help(struct sk_buff *skb, unsigned int protoff,
1114                      struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1115 {
1116         static Q931 q931;
1117         unsigned char *data = NULL;
1118         int datalen;
1119         int dataoff;
1120         int ret;
1121
1122         /* Until there's been traffic both ways, don't look in packets. */
1123         if (ctinfo != IP_CT_ESTABLISHED &&
1124             ctinfo != IP_CT_ESTABLISHED + IP_CT_IS_REPLY) {
1125                 return NF_ACCEPT;
1126         }
1127         pr_debug("nf_ct_q931: skblen = %u\n", skb->len);
1128
1129         spin_lock_bh(&nf_h323_lock);
1130
1131         /* Process each TPKT */
1132         while (get_tpkt_data(skb, protoff, ct, ctinfo,
1133                              &data, &datalen, &dataoff)) {
1134                 pr_debug("nf_ct_q931: TPKT len=%d ", datalen);
1135                 nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1136
1137                 /* Decode Q.931 signal */
1138                 ret = DecodeQ931(data, datalen, &q931);
1139                 if (ret < 0) {
1140                         pr_debug("nf_ct_q931: decoding error: %s\n",
1141                                  ret == H323_ERROR_BOUND ?
1142                                  "out of bound" : "out of range");
1143                         /* We don't drop when decoding error */
1144                         break;
1145                 }
1146
1147                 /* Process Q.931 signal */
1148                 if (process_q931(skb, ct, ctinfo, &data, dataoff, &q931) < 0)
1149                         goto drop;
1150         }
1151
1152         spin_unlock_bh(&nf_h323_lock);
1153         return NF_ACCEPT;
1154
1155       drop:
1156         spin_unlock_bh(&nf_h323_lock);
1157         if (net_ratelimit())
1158                 printk("nf_ct_q931: packet dropped\n");
1159         return NF_DROP;
1160 }
1161
1162 /****************************************************************************/
1163 static const struct nf_conntrack_expect_policy q931_exp_policy = {
1164         /* T.120 and H.245 */
1165         .max_expected           = H323_RTP_CHANNEL_MAX * 4 + 4,
1166         .timeout                = 240,
1167 };
1168
1169 static struct nf_conntrack_helper nf_conntrack_helper_q931[] __read_mostly = {
1170         {
1171                 .name                   = "Q.931",
1172                 .me                     = THIS_MODULE,
1173                 .tuple.src.l3num        = AF_INET,
1174                 .tuple.src.u.tcp.port   = __constant_htons(Q931_PORT),
1175                 .tuple.dst.protonum     = IPPROTO_TCP,
1176                 .help                   = q931_help,
1177                 .expect_policy          = &q931_exp_policy,
1178         },
1179         {
1180                 .name                   = "Q.931",
1181                 .me                     = THIS_MODULE,
1182                 .tuple.src.l3num        = AF_INET6,
1183                 .tuple.src.u.tcp.port   = __constant_htons(Q931_PORT),
1184                 .tuple.dst.protonum     = IPPROTO_TCP,
1185                 .help                   = q931_help,
1186                 .expect_policy          = &q931_exp_policy,
1187         },
1188 };
1189
1190 /****************************************************************************/
1191 static unsigned char *get_udp_data(struct sk_buff *skb, unsigned int protoff,
1192                                    int *datalen)
1193 {
1194         const struct udphdr *uh;
1195         struct udphdr _uh;
1196         int dataoff;
1197
1198         uh = skb_header_pointer(skb, protoff, sizeof(_uh), &_uh);
1199         if (uh == NULL)
1200                 return NULL;
1201         dataoff = protoff + sizeof(_uh);
1202         if (dataoff >= skb->len)
1203                 return NULL;
1204         *datalen = skb->len - dataoff;
1205         return skb_header_pointer(skb, dataoff, *datalen, h323_buffer);
1206 }
1207
1208 /****************************************************************************/
1209 static struct nf_conntrack_expect *find_expect(struct nf_conn *ct,
1210                                                union nf_inet_addr *addr,
1211                                                __be16 port)
1212 {
1213         struct net *net = nf_ct_net(ct);
1214         struct nf_conntrack_expect *exp;
1215         struct nf_conntrack_tuple tuple;
1216
1217         memset(&tuple.src.u3, 0, sizeof(tuple.src.u3));
1218         tuple.src.u.tcp.port = 0;
1219         memcpy(&tuple.dst.u3, addr, sizeof(tuple.dst.u3));
1220         tuple.dst.u.tcp.port = port;
1221         tuple.dst.protonum = IPPROTO_TCP;
1222
1223         exp = __nf_ct_expect_find(net, &tuple);
1224         if (exp && exp->master == ct)
1225                 return exp;
1226         return NULL;
1227 }
1228
1229 /****************************************************************************/
1230 static int set_expect_timeout(struct nf_conntrack_expect *exp,
1231                               unsigned timeout)
1232 {
1233         if (!exp || !del_timer(&exp->timeout))
1234                 return 0;
1235
1236         exp->timeout.expires = jiffies + timeout * HZ;
1237         add_timer(&exp->timeout);
1238
1239         return 1;
1240 }
1241
1242 /****************************************************************************/
1243 static int expect_q931(struct sk_buff *skb, struct nf_conn *ct,
1244                        enum ip_conntrack_info ctinfo,
1245                        unsigned char **data,
1246                        TransportAddress *taddr, int count)
1247 {
1248         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1249         int dir = CTINFO2DIR(ctinfo);
1250         int ret = 0;
1251         int i;
1252         __be16 port;
1253         union nf_inet_addr addr;
1254         struct nf_conntrack_expect *exp;
1255         typeof(nat_q931_hook) nat_q931;
1256
1257         /* Look for the first related address */
1258         for (i = 0; i < count; i++) {
1259                 if (get_h225_addr(ct, *data, &taddr[i], &addr, &port) &&
1260                     memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3,
1261                            sizeof(addr)) == 0 && port != 0)
1262                         break;
1263         }
1264
1265         if (i >= count)         /* Not found */
1266                 return 0;
1267
1268         /* Create expect for Q.931 */
1269         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1270                 return -1;
1271         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1272                           gkrouted_only ? /* only accept calls from GK? */
1273                                 &ct->tuplehash[!dir].tuple.src.u3 : NULL,
1274                           &ct->tuplehash[!dir].tuple.dst.u3,
1275                           IPPROTO_TCP, NULL, &port);
1276         exp->helper = nf_conntrack_helper_q931;
1277         exp->flags = NF_CT_EXPECT_PERMANENT;    /* Accept multiple calls */
1278
1279         nat_q931 = rcu_dereference(nat_q931_hook);
1280         if (nat_q931 && ct->status & IPS_NAT_MASK) {    /* Need NAT */
1281                 ret = nat_q931(skb, ct, ctinfo, data, taddr, i, port, exp);
1282         } else {                /* Conntrack only */
1283                 if (nf_ct_expect_related(exp) == 0) {
1284                         pr_debug("nf_ct_ras: expect Q.931 ");
1285                         nf_ct_dump_tuple(&exp->tuple);
1286
1287                         /* Save port for looking up expect in processing RCF */
1288                         info->sig_port[dir] = port;
1289                 } else
1290                         ret = -1;
1291         }
1292
1293         nf_ct_expect_put(exp);
1294
1295         return ret;
1296 }
1297
1298 /****************************************************************************/
1299 static int process_grq(struct sk_buff *skb, struct nf_conn *ct,
1300                        enum ip_conntrack_info ctinfo,
1301                        unsigned char **data, GatekeeperRequest *grq)
1302 {
1303         typeof(set_ras_addr_hook) set_ras_addr;
1304
1305         pr_debug("nf_ct_ras: GRQ\n");
1306
1307         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1308         if (set_ras_addr && ct->status & IPS_NAT_MASK)  /* NATed */
1309                 return set_ras_addr(skb, ct, ctinfo, data,
1310                                     &grq->rasAddress, 1);
1311         return 0;
1312 }
1313
1314 /****************************************************************************/
1315 static int process_gcf(struct sk_buff *skb, struct nf_conn *ct,
1316                        enum ip_conntrack_info ctinfo,
1317                        unsigned char **data, GatekeeperConfirm *gcf)
1318 {
1319         int dir = CTINFO2DIR(ctinfo);
1320         int ret = 0;
1321         __be16 port;
1322         union nf_inet_addr addr;
1323         struct nf_conntrack_expect *exp;
1324
1325         pr_debug("nf_ct_ras: GCF\n");
1326
1327         if (!get_h225_addr(ct, *data, &gcf->rasAddress, &addr, &port))
1328                 return 0;
1329
1330         /* Registration port is the same as discovery port */
1331         if (!memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1332             port == ct->tuplehash[dir].tuple.src.u.udp.port)
1333                 return 0;
1334
1335         /* Avoid RAS expectation loops. A GCF is never expected. */
1336         if (test_bit(IPS_EXPECTED_BIT, &ct->status))
1337                 return 0;
1338
1339         /* Need new expect */
1340         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1341                 return -1;
1342         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1343                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1344                           IPPROTO_UDP, NULL, &port);
1345         exp->helper = nf_conntrack_helper_ras;
1346
1347         if (nf_ct_expect_related(exp) == 0) {
1348                 pr_debug("nf_ct_ras: expect RAS ");
1349                 nf_ct_dump_tuple(&exp->tuple);
1350         } else
1351                 ret = -1;
1352
1353         nf_ct_expect_put(exp);
1354
1355         return ret;
1356 }
1357
1358 /****************************************************************************/
1359 static int process_rrq(struct sk_buff *skb, struct nf_conn *ct,
1360                        enum ip_conntrack_info ctinfo,
1361                        unsigned char **data, RegistrationRequest *rrq)
1362 {
1363         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1364         int ret;
1365         typeof(set_ras_addr_hook) set_ras_addr;
1366
1367         pr_debug("nf_ct_ras: RRQ\n");
1368
1369         ret = expect_q931(skb, ct, ctinfo, data,
1370                           rrq->callSignalAddress.item,
1371                           rrq->callSignalAddress.count);
1372         if (ret < 0)
1373                 return -1;
1374
1375         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1376         if (set_ras_addr && ct->status & IPS_NAT_MASK) {
1377                 ret = set_ras_addr(skb, ct, ctinfo, data,
1378                                    rrq->rasAddress.item,
1379                                    rrq->rasAddress.count);
1380                 if (ret < 0)
1381                         return -1;
1382         }
1383
1384         if (rrq->options & eRegistrationRequest_timeToLive) {
1385                 pr_debug("nf_ct_ras: RRQ TTL = %u seconds\n", rrq->timeToLive);
1386                 info->timeout = rrq->timeToLive;
1387         } else
1388                 info->timeout = default_rrq_ttl;
1389
1390         return 0;
1391 }
1392
1393 /****************************************************************************/
1394 static int process_rcf(struct sk_buff *skb, struct nf_conn *ct,
1395                        enum ip_conntrack_info ctinfo,
1396                        unsigned char **data, RegistrationConfirm *rcf)
1397 {
1398         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1399         int dir = CTINFO2DIR(ctinfo);
1400         int ret;
1401         struct nf_conntrack_expect *exp;
1402         typeof(set_sig_addr_hook) set_sig_addr;
1403
1404         pr_debug("nf_ct_ras: RCF\n");
1405
1406         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1407         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1408                 ret = set_sig_addr(skb, ct, ctinfo, data,
1409                                         rcf->callSignalAddress.item,
1410                                         rcf->callSignalAddress.count);
1411                 if (ret < 0)
1412                         return -1;
1413         }
1414
1415         if (rcf->options & eRegistrationConfirm_timeToLive) {
1416                 pr_debug("nf_ct_ras: RCF TTL = %u seconds\n", rcf->timeToLive);
1417                 info->timeout = rcf->timeToLive;
1418         }
1419
1420         if (info->timeout > 0) {
1421                 pr_debug("nf_ct_ras: set RAS connection timeout to "
1422                          "%u seconds\n", info->timeout);
1423                 nf_ct_refresh(ct, skb, info->timeout * HZ);
1424
1425                 /* Set expect timeout */
1426                 spin_lock_bh(&nf_conntrack_lock);
1427                 exp = find_expect(ct, &ct->tuplehash[dir].tuple.dst.u3,
1428                                   info->sig_port[!dir]);
1429                 if (exp) {
1430                         pr_debug("nf_ct_ras: set Q.931 expect "
1431                                  "timeout to %u seconds for",
1432                                  info->timeout);
1433                         nf_ct_dump_tuple(&exp->tuple);
1434                         set_expect_timeout(exp, info->timeout);
1435                 }
1436                 spin_unlock_bh(&nf_conntrack_lock);
1437         }
1438
1439         return 0;
1440 }
1441
1442 /****************************************************************************/
1443 static int process_urq(struct sk_buff *skb, struct nf_conn *ct,
1444                        enum ip_conntrack_info ctinfo,
1445                        unsigned char **data, UnregistrationRequest *urq)
1446 {
1447         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1448         int dir = CTINFO2DIR(ctinfo);
1449         int ret;
1450         typeof(set_sig_addr_hook) set_sig_addr;
1451
1452         pr_debug("nf_ct_ras: URQ\n");
1453
1454         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1455         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1456                 ret = set_sig_addr(skb, ct, ctinfo, data,
1457                                    urq->callSignalAddress.item,
1458                                    urq->callSignalAddress.count);
1459                 if (ret < 0)
1460                         return -1;
1461         }
1462
1463         /* Clear old expect */
1464         nf_ct_remove_expectations(ct);
1465         info->sig_port[dir] = 0;
1466         info->sig_port[!dir] = 0;
1467
1468         /* Give it 30 seconds for UCF or URJ */
1469         nf_ct_refresh(ct, skb, 30 * HZ);
1470
1471         return 0;
1472 }
1473
1474 /****************************************************************************/
1475 static int process_arq(struct sk_buff *skb, struct nf_conn *ct,
1476                        enum ip_conntrack_info ctinfo,
1477                        unsigned char **data, AdmissionRequest *arq)
1478 {
1479         const struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1480         int dir = CTINFO2DIR(ctinfo);
1481         __be16 port;
1482         union nf_inet_addr addr;
1483         typeof(set_h225_addr_hook) set_h225_addr;
1484
1485         pr_debug("nf_ct_ras: ARQ\n");
1486
1487         set_h225_addr = rcu_dereference(set_h225_addr_hook);
1488         if ((arq->options & eAdmissionRequest_destCallSignalAddress) &&
1489             get_h225_addr(ct, *data, &arq->destCallSignalAddress,
1490                           &addr, &port) &&
1491             !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1492             port == info->sig_port[dir] &&
1493             set_h225_addr && ct->status & IPS_NAT_MASK) {
1494                 /* Answering ARQ */
1495                 return set_h225_addr(skb, data, 0,
1496                                      &arq->destCallSignalAddress,
1497                                      &ct->tuplehash[!dir].tuple.dst.u3,
1498                                      info->sig_port[!dir]);
1499         }
1500
1501         if ((arq->options & eAdmissionRequest_srcCallSignalAddress) &&
1502             get_h225_addr(ct, *data, &arq->srcCallSignalAddress,
1503                           &addr, &port) &&
1504             !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1505             set_h225_addr && ct->status & IPS_NAT_MASK) {
1506                 /* Calling ARQ */
1507                 return set_h225_addr(skb, data, 0,
1508                                      &arq->srcCallSignalAddress,
1509                                      &ct->tuplehash[!dir].tuple.dst.u3,
1510                                      port);
1511         }
1512
1513         return 0;
1514 }
1515
1516 /****************************************************************************/
1517 static int process_acf(struct sk_buff *skb, struct nf_conn *ct,
1518                        enum ip_conntrack_info ctinfo,
1519                        unsigned char **data, AdmissionConfirm *acf)
1520 {
1521         int dir = CTINFO2DIR(ctinfo);
1522         int ret = 0;
1523         __be16 port;
1524         union nf_inet_addr addr;
1525         struct nf_conntrack_expect *exp;
1526         typeof(set_sig_addr_hook) set_sig_addr;
1527
1528         pr_debug("nf_ct_ras: ACF\n");
1529
1530         if (!get_h225_addr(ct, *data, &acf->destCallSignalAddress,
1531                            &addr, &port))
1532                 return 0;
1533
1534         if (!memcmp(&addr, &ct->tuplehash[dir].tuple.dst.u3, sizeof(addr))) {
1535                 /* Answering ACF */
1536                 set_sig_addr = rcu_dereference(set_sig_addr_hook);
1537                 if (set_sig_addr && ct->status & IPS_NAT_MASK)
1538                         return set_sig_addr(skb, ct, ctinfo, data,
1539                                             &acf->destCallSignalAddress, 1);
1540                 return 0;
1541         }
1542
1543         /* Need new expect */
1544         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1545                 return -1;
1546         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1547                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1548                           IPPROTO_TCP, NULL, &port);
1549         exp->flags = NF_CT_EXPECT_PERMANENT;
1550         exp->helper = nf_conntrack_helper_q931;
1551
1552         if (nf_ct_expect_related(exp) == 0) {
1553                 pr_debug("nf_ct_ras: expect Q.931 ");
1554                 nf_ct_dump_tuple(&exp->tuple);
1555         } else
1556                 ret = -1;
1557
1558         nf_ct_expect_put(exp);
1559
1560         return ret;
1561 }
1562
1563 /****************************************************************************/
1564 static int process_lrq(struct sk_buff *skb, struct nf_conn *ct,
1565                        enum ip_conntrack_info ctinfo,
1566                        unsigned char **data, LocationRequest *lrq)
1567 {
1568         typeof(set_ras_addr_hook) set_ras_addr;
1569
1570         pr_debug("nf_ct_ras: LRQ\n");
1571
1572         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1573         if (set_ras_addr && ct->status & IPS_NAT_MASK)
1574                 return set_ras_addr(skb, ct, ctinfo, data,
1575                                     &lrq->replyAddress, 1);
1576         return 0;
1577 }
1578
1579 /****************************************************************************/
1580 static int process_lcf(struct sk_buff *skb, struct nf_conn *ct,
1581                        enum ip_conntrack_info ctinfo,
1582                        unsigned char **data, LocationConfirm *lcf)
1583 {
1584         int dir = CTINFO2DIR(ctinfo);
1585         int ret = 0;
1586         __be16 port;
1587         union nf_inet_addr addr;
1588         struct nf_conntrack_expect *exp;
1589
1590         pr_debug("nf_ct_ras: LCF\n");
1591
1592         if (!get_h225_addr(ct, *data, &lcf->callSignalAddress,
1593                            &addr, &port))
1594                 return 0;
1595
1596         /* Need new expect for call signal */
1597         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1598                 return -1;
1599         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1600                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1601                           IPPROTO_TCP, NULL, &port);
1602         exp->flags = NF_CT_EXPECT_PERMANENT;
1603         exp->helper = nf_conntrack_helper_q931;
1604
1605         if (nf_ct_expect_related(exp) == 0) {
1606                 pr_debug("nf_ct_ras: expect Q.931 ");
1607                 nf_ct_dump_tuple(&exp->tuple);
1608         } else
1609                 ret = -1;
1610
1611         nf_ct_expect_put(exp);
1612
1613         /* Ignore rasAddress */
1614
1615         return ret;
1616 }
1617
1618 /****************************************************************************/
1619 static int process_irr(struct sk_buff *skb, struct nf_conn *ct,
1620                        enum ip_conntrack_info ctinfo,
1621                        unsigned char **data, InfoRequestResponse *irr)
1622 {
1623         int ret;
1624         typeof(set_ras_addr_hook) set_ras_addr;
1625         typeof(set_sig_addr_hook) set_sig_addr;
1626
1627         pr_debug("nf_ct_ras: IRR\n");
1628
1629         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1630         if (set_ras_addr && ct->status & IPS_NAT_MASK) {
1631                 ret = set_ras_addr(skb, ct, ctinfo, data,
1632                                    &irr->rasAddress, 1);
1633                 if (ret < 0)
1634                         return -1;
1635         }
1636
1637         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1638         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1639                 ret = set_sig_addr(skb, ct, ctinfo, data,
1640                                         irr->callSignalAddress.item,
1641                                         irr->callSignalAddress.count);
1642                 if (ret < 0)
1643                         return -1;
1644         }
1645
1646         return 0;
1647 }
1648
1649 /****************************************************************************/
1650 static int process_ras(struct sk_buff *skb, struct nf_conn *ct,
1651                        enum ip_conntrack_info ctinfo,
1652                        unsigned char **data, RasMessage *ras)
1653 {
1654         switch (ras->choice) {
1655         case eRasMessage_gatekeeperRequest:
1656                 return process_grq(skb, ct, ctinfo, data,
1657                                    &ras->gatekeeperRequest);
1658         case eRasMessage_gatekeeperConfirm:
1659                 return process_gcf(skb, ct, ctinfo, data,
1660                                    &ras->gatekeeperConfirm);
1661         case eRasMessage_registrationRequest:
1662                 return process_rrq(skb, ct, ctinfo, data,
1663                                    &ras->registrationRequest);
1664         case eRasMessage_registrationConfirm:
1665                 return process_rcf(skb, ct, ctinfo, data,
1666                                    &ras->registrationConfirm);
1667         case eRasMessage_unregistrationRequest:
1668                 return process_urq(skb, ct, ctinfo, data,
1669                                    &ras->unregistrationRequest);
1670         case eRasMessage_admissionRequest:
1671                 return process_arq(skb, ct, ctinfo, data,
1672                                    &ras->admissionRequest);
1673         case eRasMessage_admissionConfirm:
1674                 return process_acf(skb, ct, ctinfo, data,
1675                                    &ras->admissionConfirm);
1676         case eRasMessage_locationRequest:
1677                 return process_lrq(skb, ct, ctinfo, data,
1678                                    &ras->locationRequest);
1679         case eRasMessage_locationConfirm:
1680                 return process_lcf(skb, ct, ctinfo, data,
1681                                    &ras->locationConfirm);
1682         case eRasMessage_infoRequestResponse:
1683                 return process_irr(skb, ct, ctinfo, data,
1684                                    &ras->infoRequestResponse);
1685         default:
1686                 pr_debug("nf_ct_ras: RAS message %d\n", ras->choice);
1687                 break;
1688         }
1689
1690         return 0;
1691 }
1692
1693 /****************************************************************************/
1694 static int ras_help(struct sk_buff *skb, unsigned int protoff,
1695                     struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1696 {
1697         static RasMessage ras;
1698         unsigned char *data;
1699         int datalen = 0;
1700         int ret;
1701
1702         pr_debug("nf_ct_ras: skblen = %u\n", skb->len);
1703
1704         spin_lock_bh(&nf_h323_lock);
1705
1706         /* Get UDP data */
1707         data = get_udp_data(skb, protoff, &datalen);
1708         if (data == NULL)
1709                 goto accept;
1710         pr_debug("nf_ct_ras: RAS message len=%d ", datalen);
1711         nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1712
1713         /* Decode RAS message */
1714         ret = DecodeRasMessage(data, datalen, &ras);
1715         if (ret < 0) {
1716                 pr_debug("nf_ct_ras: decoding error: %s\n",
1717                          ret == H323_ERROR_BOUND ?
1718                          "out of bound" : "out of range");
1719                 goto accept;
1720         }
1721
1722         /* Process RAS message */
1723         if (process_ras(skb, ct, ctinfo, &data, &ras) < 0)
1724                 goto drop;
1725
1726       accept:
1727         spin_unlock_bh(&nf_h323_lock);
1728         return NF_ACCEPT;
1729
1730       drop:
1731         spin_unlock_bh(&nf_h323_lock);
1732         if (net_ratelimit())
1733                 printk("nf_ct_ras: packet dropped\n");
1734         return NF_DROP;
1735 }
1736
1737 /****************************************************************************/
1738 static const struct nf_conntrack_expect_policy ras_exp_policy = {
1739         .max_expected           = 32,
1740         .timeout                = 240,
1741 };
1742
1743 static struct nf_conntrack_helper nf_conntrack_helper_ras[] __read_mostly = {
1744         {
1745                 .name                   = "RAS",
1746                 .me                     = THIS_MODULE,
1747                 .tuple.src.l3num        = AF_INET,
1748                 .tuple.src.u.udp.port   = __constant_htons(RAS_PORT),
1749                 .tuple.dst.protonum     = IPPROTO_UDP,
1750                 .help                   = ras_help,
1751                 .expect_policy          = &ras_exp_policy,
1752         },
1753         {
1754                 .name                   = "RAS",
1755                 .me                     = THIS_MODULE,
1756                 .tuple.src.l3num        = AF_INET6,
1757                 .tuple.src.u.udp.port   = __constant_htons(RAS_PORT),
1758                 .tuple.dst.protonum     = IPPROTO_UDP,
1759                 .help                   = ras_help,
1760                 .expect_policy          = &ras_exp_policy,
1761         },
1762 };
1763
1764 /****************************************************************************/
1765 static void __exit nf_conntrack_h323_fini(void)
1766 {
1767         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[1]);
1768         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1769         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1770         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1771         nf_conntrack_helper_unregister(&nf_conntrack_helper_h245);
1772         kfree(h323_buffer);
1773         pr_debug("nf_ct_h323: fini\n");
1774 }
1775
1776 /****************************************************************************/
1777 static int __init nf_conntrack_h323_init(void)
1778 {
1779         int ret;
1780
1781         h323_buffer = kmalloc(65536, GFP_KERNEL);
1782         if (!h323_buffer)
1783                 return -ENOMEM;
1784         ret = nf_conntrack_helper_register(&nf_conntrack_helper_h245);
1785         if (ret < 0)
1786                 goto err1;
1787         ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[0]);
1788         if (ret < 0)
1789                 goto err2;
1790         ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[1]);
1791         if (ret < 0)
1792                 goto err3;
1793         ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[0]);
1794         if (ret < 0)
1795                 goto err4;
1796         ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[1]);
1797         if (ret < 0)
1798                 goto err5;
1799         pr_debug("nf_ct_h323: init success\n");
1800         return 0;
1801
1802 err5:
1803         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1804 err4:
1805         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1806 err3:
1807         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1808 err2:
1809         nf_conntrack_helper_unregister(&nf_conntrack_helper_h245);
1810 err1:
1811         kfree(h323_buffer);
1812         return ret;
1813 }
1814
1815 /****************************************************************************/
1816 module_init(nf_conntrack_h323_init);
1817 module_exit(nf_conntrack_h323_fini);
1818
1819 EXPORT_SYMBOL_GPL(get_h225_addr);
1820 EXPORT_SYMBOL_GPL(set_h245_addr_hook);
1821 EXPORT_SYMBOL_GPL(set_h225_addr_hook);
1822 EXPORT_SYMBOL_GPL(set_sig_addr_hook);
1823 EXPORT_SYMBOL_GPL(set_ras_addr_hook);
1824 EXPORT_SYMBOL_GPL(nat_rtp_rtcp_hook);
1825 EXPORT_SYMBOL_GPL(nat_t120_hook);
1826 EXPORT_SYMBOL_GPL(nat_h245_hook);
1827 EXPORT_SYMBOL_GPL(nat_callforwarding_hook);
1828 EXPORT_SYMBOL_GPL(nat_q931_hook);
1829
1830 MODULE_AUTHOR("Jing Min Zhao <zhaojingmin@users.sourceforge.net>");
1831 MODULE_DESCRIPTION("H.323 connection tracking helper");
1832 MODULE_LICENSE("GPL");
1833 MODULE_ALIAS("ip_conntrack_h323");