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, ct->tuplehash[!dir].tuple.src.l3num,
 281                           &ct->tuplehash[!dir].tuple.src.u3,
 282                           &ct->tuplehash[!dir].tuple.dst.u3,
 283                           IPPROTO_UDP, NULL, &rtp_port);
 284
 285         /* Create expect for RTCP */
 286         if ((rtcp_exp = nf_ct_expect_alloc(ct)) == NULL) {
 287                 nf_ct_expect_put(rtp_exp);
 288                 return -1;
 289         }
 290         nf_ct_expect_init(rtcp_exp, ct->tuplehash[!dir].tuple.src.l3num,
 291                           &ct->tuplehash[!dir].tuple.src.u3,
 292                           &ct->tuplehash[!dir].tuple.dst.u3,
 293                           IPPROTO_UDP, NULL, &rtcp_port);
 294
 295         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 296                    &ct->tuplehash[!dir].tuple.dst.u3,
 297                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 298                    (nat_rtp_rtcp = rcu_dereference(nat_rtp_rtcp_hook)) &&
 299                    ct->status & IPS_NAT_MASK) {
 300                 /* NAT needed */
 301                 ret = nat_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
 302                                    taddr, port, rtp_port, rtp_exp, rtcp_exp);
 303         } else {                /* Conntrack only */
 304                 if (nf_ct_expect_related(rtp_exp) == 0) {
 305                         if (nf_ct_expect_related(rtcp_exp) == 0) {
 306                                 pr_debug("nf_ct_h323: expect RTP ");
 307                                 NF_CT_DUMP_TUPLE(&rtp_exp->tuple);
 308                                 pr_debug("nf_ct_h323: expect RTCP ");
 309                                 NF_CT_DUMP_TUPLE(&rtcp_exp->tuple);
 310                         } else {
 311                                 nf_ct_unexpect_related(rtp_exp);
 312                                 ret = -1;
 313                         }
 314                 } else
 315                         ret = -1;
 316         }
 317
 318         nf_ct_expect_put(rtp_exp);
 319         nf_ct_expect_put(rtcp_exp);
 320
 321         return ret;
 322 }
 323
 324 /****************************************************************************/
 325 static int expect_t120(struct sk_buff *skb,
 326                        struct nf_conn *ct,
 327                        enum ip_conntrack_info ctinfo,
 328                        unsigned char **data, int dataoff,
 329                        H245_TransportAddress *taddr)
 330 {
 331         int dir = CTINFO2DIR(ctinfo);
 332         int ret = 0;
 333         __be16 port;
 334         union nf_inet_addr addr;
 335         struct nf_conntrack_expect *exp;
 336         typeof(nat_t120_hook) nat_t120;
 337
 338         /* Read T.120 address */
 339         if (!get_h245_addr(ct, *data, taddr, &addr, &port) ||
 340             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
 341             port == 0)
 342                 return 0;
 343
 344         /* Create expect for T.120 connections */
 345         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
 346                 return -1;
 347         nf_ct_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num,
 348                           &ct->tuplehash[!dir].tuple.src.u3,
 349                           &ct->tuplehash[!dir].tuple.dst.u3,
 350                           IPPROTO_TCP, NULL, &port);
 351         exp->flags = NF_CT_EXPECT_PERMANENT;    /* Accept multiple channels */
 352
 353         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 354                    &ct->tuplehash[!dir].tuple.dst.u3,
 355                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 356             (nat_t120 = rcu_dereference(nat_t120_hook)) &&
 357             ct->status & IPS_NAT_MASK) {
 358                 /* NAT needed */
 359                 ret = nat_t120(skb, ct, ctinfo, data, dataoff, taddr,
 360                                port, exp);
 361         } else {                /* Conntrack only */
 362                 if (nf_ct_expect_related(exp) == 0) {
 363                         pr_debug("nf_ct_h323: expect T.120 ");
 364                         NF_CT_DUMP_TUPLE(&exp->tuple);
 365                 } else
 366                         ret = -1;
 367         }
 368
 369         nf_ct_expect_put(exp);
 370
 371         return ret;
 372 }
 373
 374 /****************************************************************************/
 375 static int process_h245_channel(struct sk_buff *skb,
 376                                 struct nf_conn *ct,
 377                                 enum ip_conntrack_info ctinfo,
 378                                 unsigned char **data, int dataoff,
 379                                 H2250LogicalChannelParameters *channel)
 380 {
 381         int ret;
 382
 383         if (channel->options & eH2250LogicalChannelParameters_mediaChannel) {
 384                 /* RTP */
 385                 ret = expect_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
 386                                       &channel->mediaChannel);
 387                 if (ret < 0)
 388                         return -1;
 389         }
 390
 391         if (channel->
 392             options & eH2250LogicalChannelParameters_mediaControlChannel) {
 393                 /* RTCP */
 394                 ret = expect_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
 395                                       &channel->mediaControlChannel);
 396                 if (ret < 0)
 397                         return -1;
 398         }
 399
 400         return 0;
 401 }
 402
 403 /****************************************************************************/
 404 static int process_olc(struct sk_buff *skb, struct nf_conn *ct,
 405                        enum ip_conntrack_info ctinfo,
 406                        unsigned char **data, int dataoff,
 407                        OpenLogicalChannel *olc)
 408 {
 409         int ret;
 410
 411         pr_debug("nf_ct_h323: OpenLogicalChannel\n");
 412
 413         if (olc->forwardLogicalChannelParameters.multiplexParameters.choice ==
 414             eOpenLogicalChannel_forwardLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters)
 415         {
 416                 ret = process_h245_channel(skb, ct, ctinfo, data, dataoff,
 417                                            &olc->
 418                                            forwardLogicalChannelParameters.
 419                                            multiplexParameters.
 420                                            h2250LogicalChannelParameters);
 421                 if (ret < 0)
 422                         return -1;
 423         }
 424
 425         if ((olc->options &
 426              eOpenLogicalChannel_reverseLogicalChannelParameters) &&
 427             (olc->reverseLogicalChannelParameters.options &
 428              eOpenLogicalChannel_reverseLogicalChannelParameters_multiplexParameters)
 429             && (olc->reverseLogicalChannelParameters.multiplexParameters.
 430                 choice ==
 431                 eOpenLogicalChannel_reverseLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters))
 432         {
 433                 ret =
 434                     process_h245_channel(skb, ct, ctinfo, data, dataoff,
 435                                          &olc->
 436                                          reverseLogicalChannelParameters.
 437                                          multiplexParameters.
 438                                          h2250LogicalChannelParameters);
 439                 if (ret < 0)
 440                         return -1;
 441         }
 442
 443         if ((olc->options & eOpenLogicalChannel_separateStack) &&
 444             olc->forwardLogicalChannelParameters.dataType.choice ==
 445             eDataType_data &&
 446             olc->forwardLogicalChannelParameters.dataType.data.application.
 447             choice == eDataApplicationCapability_application_t120 &&
 448             olc->forwardLogicalChannelParameters.dataType.data.application.
 449             t120.choice == eDataProtocolCapability_separateLANStack &&
 450             olc->separateStack.networkAddress.choice ==
 451             eNetworkAccessParameters_networkAddress_localAreaAddress) {
 452                 ret = expect_t120(skb, ct, ctinfo, data, dataoff,
 453                                   &olc->separateStack.networkAddress.
 454                                   localAreaAddress);
 455                 if (ret < 0)
 456                         return -1;
 457         }
 458
 459         return 0;
 460 }
 461
 462 /****************************************************************************/
 463 static int process_olca(struct sk_buff *skb, struct nf_conn *ct,
 464                         enum ip_conntrack_info ctinfo,
 465                         unsigned char **data, int dataoff,
 466                         OpenLogicalChannelAck *olca)
 467 {
 468         H2250LogicalChannelAckParameters *ack;
 469         int ret;
 470
 471         pr_debug("nf_ct_h323: OpenLogicalChannelAck\n");
 472
 473         if ((olca->options &
 474              eOpenLogicalChannelAck_reverseLogicalChannelParameters) &&
 475             (olca->reverseLogicalChannelParameters.options &
 476              eOpenLogicalChannelAck_reverseLogicalChannelParameters_multiplexParameters)
 477             && (olca->reverseLogicalChannelParameters.multiplexParameters.
 478                 choice ==
 479                 eOpenLogicalChannelAck_reverseLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters))
 480         {
 481                 ret = process_h245_channel(skb, ct, ctinfo, data, dataoff,
 482                                            &olca->
 483                                            reverseLogicalChannelParameters.
 484                                            multiplexParameters.
 485                                            h2250LogicalChannelParameters);
 486                 if (ret < 0)
 487                         return -1;
 488         }
 489
 490         if ((olca->options &
 491              eOpenLogicalChannelAck_forwardMultiplexAckParameters) &&
 492             (olca->forwardMultiplexAckParameters.choice ==
 493              eOpenLogicalChannelAck_forwardMultiplexAckParameters_h2250LogicalChannelAckParameters))
 494         {
 495                 ack = &olca->forwardMultiplexAckParameters.
 496                     h2250LogicalChannelAckParameters;
 497                 if (ack->options &
 498                     eH2250LogicalChannelAckParameters_mediaChannel) {
 499                         /* RTP */
 500                         ret = expect_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
 501                                               &ack->mediaChannel);
 502                         if (ret < 0)
 503                                 return -1;
 504                 }
 505
 506                 if (ack->options &
 507                     eH2250LogicalChannelAckParameters_mediaControlChannel) {
 508                         /* RTCP */
 509                         ret = expect_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
 510                                               &ack->mediaControlChannel);
 511                         if (ret < 0)
 512                                 return -1;
 513                 }
 514         }
 515
 516         if ((olca->options & eOpenLogicalChannelAck_separateStack) &&
 517                 olca->separateStack.networkAddress.choice ==
 518                 eNetworkAccessParameters_networkAddress_localAreaAddress) {
 519                 ret = expect_t120(skb, ct, ctinfo, data, dataoff,
 520                                   &olca->separateStack.networkAddress.
 521                                   localAreaAddress);
 522                 if (ret < 0)
 523                         return -1;
 524         }
 525
 526         return 0;
 527 }
 528
 529 /****************************************************************************/
 530 static int process_h245(struct sk_buff *skb, struct nf_conn *ct,
 531                         enum ip_conntrack_info ctinfo,
 532                         unsigned char **data, int dataoff,
 533                         MultimediaSystemControlMessage *mscm)
 534 {
 535         switch (mscm->choice) {
 536         case eMultimediaSystemControlMessage_request:
 537                 if (mscm->request.choice ==
 538                     eRequestMessage_openLogicalChannel) {
 539                         return process_olc(skb, ct, ctinfo, data, dataoff,
 540                                            &mscm->request.openLogicalChannel);
 541                 }
 542                 pr_debug("nf_ct_h323: H.245 Request %d\n",
 543                          mscm->request.choice);
 544                 break;
 545         case eMultimediaSystemControlMessage_response:
 546                 if (mscm->response.choice ==
 547                     eResponseMessage_openLogicalChannelAck) {
 548                         return process_olca(skb, ct, ctinfo, data, dataoff,
 549                                             &mscm->response.
 550                                             openLogicalChannelAck);
 551                 }
 552                 pr_debug("nf_ct_h323: H.245 Response %d\n",
 553                          mscm->response.choice);
 554                 break;
 555         default:
 556                 pr_debug("nf_ct_h323: H.245 signal %d\n", mscm->choice);
 557                 break;
 558         }
 559
 560         return 0;
 561 }
 562
 563 /****************************************************************************/
 564 static int h245_help(struct sk_buff *skb, unsigned int protoff,
 565                      struct nf_conn *ct, enum ip_conntrack_info ctinfo)
 566 {
 567         static MultimediaSystemControlMessage mscm;
 568         unsigned char *data = NULL;
 569         int datalen;
 570         int dataoff;
 571         int ret;
 572
 573         /* Until there's been traffic both ways, don't look in packets. */
 574         if (ctinfo != IP_CT_ESTABLISHED &&
 575             ctinfo != IP_CT_ESTABLISHED + IP_CT_IS_REPLY) {
 576                 return NF_ACCEPT;
 577         }
 578         pr_debug("nf_ct_h245: skblen = %u\n", skb->len);
 579
 580         spin_lock_bh(&nf_h323_lock);
 581
 582         /* Process each TPKT */
 583         while (get_tpkt_data(skb, protoff, ct, ctinfo,
 584                              &data, &datalen, &dataoff)) {
 585                 pr_debug("nf_ct_h245: TPKT len=%d ", datalen);
 586                 NF_CT_DUMP_TUPLE(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
 587
 588                 /* Decode H.245 signal */
 589                 ret = DecodeMultimediaSystemControlMessage(data, datalen,
 590                                                            &mscm);
 591                 if (ret < 0) {
 592                         pr_debug("nf_ct_h245: decoding error: %s\n",
 593                                  ret == H323_ERROR_BOUND ?
 594                                  "out of bound" : "out of range");
 595                         /* We don't drop when decoding error */
 596                         break;
 597                 }
 598
 599                 /* Process H.245 signal */
 600                 if (process_h245(skb, ct, ctinfo, &data, dataoff, &mscm) < 0)
 601                         goto drop;
 602         }
 603
 604         spin_unlock_bh(&nf_h323_lock);
 605         return NF_ACCEPT;
 606
 607       drop:
 608         spin_unlock_bh(&nf_h323_lock);
 609         if (net_ratelimit())
 610                 printk("nf_ct_h245: packet dropped\n");
 611         return NF_DROP;
 612 }
 613
 614 /****************************************************************************/
 615 static struct nf_conntrack_helper nf_conntrack_helper_h245 __read_mostly = {
 616         .name                   = "H.245",
 617         .me                     = THIS_MODULE,
 618         .max_expected           = H323_RTP_CHANNEL_MAX * 4 + 2 /* T.120 */,
 619         .timeout                = 240,
 620         .tuple.dst.protonum     = IPPROTO_UDP,
 621         .help                   = h245_help
 622 };
 623
 624 /****************************************************************************/
 625 int get_h225_addr(struct nf_conn *ct, unsigned char *data,
 626                   TransportAddress *taddr,
 627                   union nf_inet_addr *addr, __be16 *port)
 628 {
 629         const unsigned char *p;
 630         int family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 631         int len;
 632
 633         switch (taddr->choice) {
 634         case eTransportAddress_ipAddress:
 635                 if (family != AF_INET)
 636                         return 0;
 637                 p = data + taddr->ipAddress.ip;
 638                 len = 4;
 639                 break;
 640         case eTransportAddress_ip6Address:
 641                 if (family != AF_INET6)
 642                         return 0;
 643                 p = data + taddr->ip6Address.ip;
 644                 len = 16;
 645                 break;
 646         default:
 647                 return 0;
 648         }
 649
 650         memcpy(addr, p, len);
 651         memset((void *)addr + len, 0, sizeof(*addr) - len);
 652         memcpy(port, p + len, sizeof(__be16));
 653
 654         return 1;
 655 }
 656
 657 /****************************************************************************/
 658 static int expect_h245(struct sk_buff *skb, struct nf_conn *ct,
 659                        enum ip_conntrack_info ctinfo,
 660                        unsigned char **data, int dataoff,
 661                        TransportAddress *taddr)
 662 {
 663         int dir = CTINFO2DIR(ctinfo);
 664         int ret = 0;
 665         __be16 port;
 666         union nf_inet_addr addr;
 667         struct nf_conntrack_expect *exp;
 668         typeof(nat_h245_hook) nat_h245;
 669
 670         /* Read h245Address */
 671         if (!get_h225_addr(ct, *data, taddr, &addr, &port) ||
 672             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
 673             port == 0)
 674                 return 0;
 675
 676         /* Create expect for h245 connection */
 677         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
 678                 return -1;
 679         nf_ct_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num,
 680                           &ct->tuplehash[!dir].tuple.src.u3,
 681                           &ct->tuplehash[!dir].tuple.dst.u3,
 682                           IPPROTO_TCP, NULL, &port);
 683         exp->helper = &nf_conntrack_helper_h245;
 684
 685         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 686                    &ct->tuplehash[!dir].tuple.dst.u3,
 687                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 688             (nat_h245 = rcu_dereference(nat_h245_hook)) &&
 689             ct->status & IPS_NAT_MASK) {
 690                 /* NAT needed */
 691                 ret = nat_h245(skb, ct, ctinfo, data, dataoff, taddr,
 692                                port, exp);
 693         } else {                /* Conntrack only */
 694                 if (nf_ct_expect_related(exp) == 0) {
 695                         pr_debug("nf_ct_q931: expect H.245 ");
 696                         NF_CT_DUMP_TUPLE(&exp->tuple);
 697                 } else
 698                         ret = -1;
 699         }
 700
 701         nf_ct_expect_put(exp);
 702
 703         return ret;
 704 }
 705
 706 /* If the calling party is on the same side of the forward-to party,
 707  * we don't need to track the second call */
 708 static int callforward_do_filter(const union nf_inet_addr *src,
 709                                  const union nf_inet_addr *dst, int family)
 710 {
 711         const struct nf_afinfo *afinfo;
 712         struct flowi fl1, fl2;
 713         int ret = 0;
 714
 715         /* rcu_read_lock()ed by nf_hook_slow() */
 716         afinfo = nf_get_afinfo(family);
 717         if (!afinfo)
 718                 return 0;
 719
 720         memset(&fl1, 0, sizeof(fl1));
 721         memset(&fl2, 0, sizeof(fl2));
 722
 723         switch (family) {
 724         case AF_INET: {
 725                 struct rtable *rt1, *rt2;
 726
 727                 fl1.fl4_dst = src->ip;
 728                 fl2.fl4_dst = dst->ip;
 729                 if (!afinfo->route((struct dst_entry **)&rt1, &fl1)) {
 730                         if (!afinfo->route((struct dst_entry **)&rt2, &fl2)) {
 731                                 if (rt1->rt_gateway == rt2->rt_gateway &&
 732                                     rt1->u.dst.dev  == rt2->u.dst.dev)
 733                                         ret = 1;
 734                                 dst_release(&rt2->u.dst);
 735                         }
 736                         dst_release(&rt1->u.dst);
 737                 }
 738                 break;
 739         }
 740 #if defined(CONFIG_NF_CONNTRACK_IPV6) || \
 741     defined(CONFIG_NF_CONNTRACK_IPV6_MODULE)
 742         case AF_INET6: {
 743                 struct rt6_info *rt1, *rt2;
 744
 745                 memcpy(&fl1.fl6_dst, src, sizeof(fl1.fl6_dst));
 746                 memcpy(&fl2.fl6_dst, dst, sizeof(fl2.fl6_dst));
 747                 if (!afinfo->route((struct dst_entry **)&rt1, &fl1)) {
 748                         if (!afinfo->route((struct dst_entry **)&rt2, &fl2)) {
 749                                 if (!memcmp(&rt1->rt6i_gateway, &rt2->rt6i_gateway,
 750                                             sizeof(rt1->rt6i_gateway)) &&
 751                                     rt1->u.dst.dev == rt2->u.dst.dev)
 752                                         ret = 1;
 753                                 dst_release(&rt2->u.dst);
 754                         }
 755                         dst_release(&rt1->u.dst);
 756                 }
 757                 break;
 758         }
 759 #endif
 760         }
 761         return ret;
 762
 763 }
 764
 765 /****************************************************************************/
 766 static int expect_callforwarding(struct sk_buff *skb,
 767                                  struct nf_conn *ct,
 768                                  enum ip_conntrack_info ctinfo,
 769                                  unsigned char **data, int dataoff,
 770                                  TransportAddress *taddr)
 771 {
 772         int dir = CTINFO2DIR(ctinfo);
 773         int ret = 0;
 774         __be16 port;
 775         union nf_inet_addr addr;
 776         struct nf_conntrack_expect *exp;
 777         typeof(nat_callforwarding_hook) nat_callforwarding;
 778
 779         /* Read alternativeAddress */
 780         if (!get_h225_addr(ct, *data, taddr, &addr, &port) || port == 0)
 781                 return 0;
 782
 783         /* If the calling party is on the same side of the forward-to party,
 784          * we don't need to track the second call */
 785         if (callforward_filter &&
 786             callforward_do_filter(&addr, &ct->tuplehash[!dir].tuple.src.u3,
 787                                   ct->tuplehash[!dir].tuple.src.l3num)) {
 788                 pr_debug("nf_ct_q931: Call Forwarding not tracked\n");
 789                 return 0;
 790         }
 791
 792         /* Create expect for the second call leg */
 793         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
 794                 return -1;
 795         nf_ct_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num,
 796                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
 797                           IPPROTO_TCP, NULL, &port);
 798         exp->helper = nf_conntrack_helper_q931;
 799
 800         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 801                    &ct->tuplehash[!dir].tuple.dst.u3,
 802                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 803             (nat_callforwarding = rcu_dereference(nat_callforwarding_hook)) &&
 804             ct->status & IPS_NAT_MASK) {
 805                 /* Need NAT */
 806                 ret = nat_callforwarding(skb, ct, ctinfo, data, dataoff,
 807                                          taddr, port, exp);
 808         } else {                /* Conntrack only */
 809                 if (nf_ct_expect_related(exp) == 0) {
 810                         pr_debug("nf_ct_q931: expect Call Forwarding ");
 811                         NF_CT_DUMP_TUPLE(&exp->tuple);
 812                 } else
 813                         ret = -1;
 814         }
 815
 816         nf_ct_expect_put(exp);
 817
 818         return ret;
 819 }
 820
 821 /****************************************************************************/
 822 static int process_setup(struct sk_buff *skb, struct nf_conn *ct,
 823                          enum ip_conntrack_info ctinfo,
 824                          unsigned char **data, int dataoff,
 825                          Setup_UUIE *setup)
 826 {
 827         int dir = CTINFO2DIR(ctinfo);
 828         int ret;
 829         int i;
 830         __be16 port;
 831         union nf_inet_addr addr;
 832         typeof(set_h225_addr_hook) set_h225_addr;
 833
 834         pr_debug("nf_ct_q931: Setup\n");
 835
 836         if (setup->options & eSetup_UUIE_h245Address) {
 837                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
 838                                   &setup->h245Address);
 839                 if (ret < 0)
 840                         return -1;
 841         }
 842
 843         set_h225_addr = rcu_dereference(set_h225_addr_hook);
 844         if ((setup->options & eSetup_UUIE_destCallSignalAddress) &&
 845             (set_h225_addr) && ct->status & IPS_NAT_MASK &&
 846             get_h225_addr(ct, *data, &setup->destCallSignalAddress,
 847                           &addr, &port) &&
 848             memcmp(&addr, &ct->tuplehash[!dir].tuple.src.u3, sizeof(addr))) {
 849                 pr_debug("nf_ct_q931: set destCallSignalAddress "
 850                          NIP6_FMT ":%hu->" NIP6_FMT ":%hu\n",
 851                          NIP6(*(struct in6_addr *)&addr), ntohs(port),
 852                          NIP6(*(struct in6_addr *)&ct->tuplehash[!dir].tuple.src.u3),
 853                          ntohs(ct->tuplehash[!dir].tuple.src.u.tcp.port));
 854                 ret = set_h225_addr(skb, data, dataoff,
 855                                     &setup->destCallSignalAddress,
 856                                     &ct->tuplehash[!dir].tuple.src.u3,
 857                                     ct->tuplehash[!dir].tuple.src.u.tcp.port);
 858                 if (ret < 0)
 859                         return -1;
 860         }
 861
 862         if ((setup->options & eSetup_UUIE_sourceCallSignalAddress) &&
 863             (set_h225_addr) && ct->status & IPS_NAT_MASK &&
 864             get_h225_addr(ct, *data, &setup->sourceCallSignalAddress,
 865                           &addr, &port) &&
 866             memcmp(&addr, &ct->tuplehash[!dir].tuple.dst.u3, sizeof(addr))) {
 867                 pr_debug("nf_ct_q931: set sourceCallSignalAddress "
 868                          NIP6_FMT ":%hu->" NIP6_FMT ":%hu\n",
 869                          NIP6(*(struct in6_addr *)&addr), ntohs(port),
 870                          NIP6(*(struct in6_addr *)&ct->tuplehash[!dir].tuple.dst.u3),
 871                          ntohs(ct->tuplehash[!dir].tuple.dst.u.tcp.port));
 872                 ret = set_h225_addr(skb, data, dataoff,
 873                                     &setup->sourceCallSignalAddress,
 874                                     &ct->tuplehash[!dir].tuple.dst.u3,
 875                                     ct->tuplehash[!dir].tuple.dst.u.tcp.port);
 876                 if (ret < 0)
 877                         return -1;
 878         }
 879
 880         if (setup->options & eSetup_UUIE_fastStart) {
 881                 for (i = 0; i < setup->fastStart.count; i++) {
 882                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
 883                                           &setup->fastStart.item[i]);
 884                         if (ret < 0)
 885                                 return -1;
 886                 }
 887         }
 888
 889         return 0;
 890 }
 891
 892 /****************************************************************************/
 893 static int process_callproceeding(struct sk_buff *skb,
 894                                   struct nf_conn *ct,
 895                                   enum ip_conntrack_info ctinfo,
 896                                   unsigned char **data, int dataoff,
 897                                   CallProceeding_UUIE *callproc)
 898 {
 899         int ret;
 900         int i;
 901
 902         pr_debug("nf_ct_q931: CallProceeding\n");
 903
 904         if (callproc->options & eCallProceeding_UUIE_h245Address) {
 905                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
 906                                   &callproc->h245Address);
 907                 if (ret < 0)
 908                         return -1;
 909         }
 910
 911         if (callproc->options & eCallProceeding_UUIE_fastStart) {
 912                 for (i = 0; i < callproc->fastStart.count; i++) {
 913                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
 914                                           &callproc->fastStart.item[i]);
 915                         if (ret < 0)
 916                                 return -1;
 917                 }
 918         }
 919
 920         return 0;
 921 }
 922
 923 /****************************************************************************/
 924 static int process_connect(struct sk_buff *skb, struct nf_conn *ct,
 925                            enum ip_conntrack_info ctinfo,
 926                            unsigned char **data, int dataoff,
 927                            Connect_UUIE *connect)
 928 {
 929         int ret;
 930         int i;
 931
 932         pr_debug("nf_ct_q931: Connect\n");
 933
 934         if (connect->options & eConnect_UUIE_h245Address) {
 935                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
 936                                   &connect->h245Address);
 937                 if (ret < 0)
 938                         return -1;
 939         }
 940
 941         if (connect->options & eConnect_UUIE_fastStart) {
 942                 for (i = 0; i < connect->fastStart.count; i++) {
 943                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
 944                                           &connect->fastStart.item[i]);
 945                         if (ret < 0)
 946                                 return -1;
 947                 }
 948         }
 949
 950         return 0;
 951 }
 952
 953 /****************************************************************************/
 954 static int process_alerting(struct sk_buff *skb, struct nf_conn *ct,
 955                             enum ip_conntrack_info ctinfo,
 956                             unsigned char **data, int dataoff,
 957                             Alerting_UUIE *alert)
 958 {
 959         int ret;
 960         int i;
 961
 962         pr_debug("nf_ct_q931: Alerting\n");
 963
 964         if (alert->options & eAlerting_UUIE_h245Address) {
 965                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
 966                                   &alert->h245Address);
 967                 if (ret < 0)
 968                         return -1;
 969         }
 970
 971         if (alert->options & eAlerting_UUIE_fastStart) {
 972                 for (i = 0; i < alert->fastStart.count; i++) {
 973                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
 974                                           &alert->fastStart.item[i]);
 975                         if (ret < 0)
 976                                 return -1;
 977                 }
 978         }
 979
 980         return 0;
 981 }
 982
 983 /****************************************************************************/
 984 static int process_facility(struct sk_buff *skb, struct nf_conn *ct,
 985                             enum ip_conntrack_info ctinfo,
 986                             unsigned char **data, int dataoff,
 987                             Facility_UUIE *facility)
 988 {
 989         int ret;
 990         int i;
 991
 992         pr_debug("nf_ct_q931: Facility\n");
 993
 994         if (facility->reason.choice == eFacilityReason_callForwarded) {
 995                 if (facility->options & eFacility_UUIE_alternativeAddress)
 996                         return expect_callforwarding(skb, ct, ctinfo, data,
 997                                                      dataoff,
 998                                                      &facility->
 999                                                      alternativeAddress);
1000                 return 0;
1001         }
1002
1003         if (facility->options & eFacility_UUIE_h245Address) {
1004                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
1005                                   &facility->h245Address);
1006                 if (ret < 0)
1007                         return -1;
1008         }
1009
1010         if (facility->options & eFacility_UUIE_fastStart) {
1011                 for (i = 0; i < facility->fastStart.count; i++) {
1012                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
1013                                           &facility->fastStart.item[i]);
1014                         if (ret < 0)
1015                                 return -1;
1016                 }
1017         }
1018
1019         return 0;
1020 }
1021
1022 /****************************************************************************/
1023 static int process_progress(struct sk_buff *skb, struct nf_conn *ct,
1024                             enum ip_conntrack_info ctinfo,
1025                             unsigned char **data, int dataoff,
1026                             Progress_UUIE *progress)
1027 {
1028         int ret;
1029         int i;
1030
1031         pr_debug("nf_ct_q931: Progress\n");
1032
1033         if (progress->options & eProgress_UUIE_h245Address) {
1034                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
1035                                   &progress->h245Address);
1036                 if (ret < 0)
1037                         return -1;
1038         }
1039
1040         if (progress->options & eProgress_UUIE_fastStart) {
1041                 for (i = 0; i < progress->fastStart.count; i++) {
1042                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
1043                                           &progress->fastStart.item[i]);
1044                         if (ret < 0)
1045                                 return -1;
1046                 }
1047         }
1048
1049         return 0;
1050 }
1051
1052 /****************************************************************************/
1053 static int process_q931(struct sk_buff *skb, struct nf_conn *ct,
1054                         enum ip_conntrack_info ctinfo,
1055                         unsigned char **data, int dataoff, Q931 *q931)
1056 {
1057         H323_UU_PDU *pdu = &q931->UUIE.h323_uu_pdu;
1058         int i;
1059         int ret = 0;
1060
1061         switch (pdu->h323_message_body.choice) {
1062         case eH323_UU_PDU_h323_message_body_setup:
1063                 ret = process_setup(skb, ct, ctinfo, data, dataoff,
1064                                     &pdu->h323_message_body.setup);
1065                 break;
1066         case eH323_UU_PDU_h323_message_body_callProceeding:
1067                 ret = process_callproceeding(skb, ct, ctinfo, data, dataoff,
1068                                              &pdu->h323_message_body.
1069                                              callProceeding);
1070                 break;
1071         case eH323_UU_PDU_h323_message_body_connect:
1072                 ret = process_connect(skb, ct, ctinfo, data, dataoff,
1073                                       &pdu->h323_message_body.connect);
1074                 break;
1075         case eH323_UU_PDU_h323_message_body_alerting:
1076                 ret = process_alerting(skb, ct, ctinfo, data, dataoff,
1077                                        &pdu->h323_message_body.alerting);
1078                 break;
1079         case eH323_UU_PDU_h323_message_body_facility:
1080                 ret = process_facility(skb, ct, ctinfo, data, dataoff,
1081                                        &pdu->h323_message_body.facility);
1082                 break;
1083         case eH323_UU_PDU_h323_message_body_progress:
1084                 ret = process_progress(skb, ct, ctinfo, data, dataoff,
1085                                        &pdu->h323_message_body.progress);
1086                 break;
1087         default:
1088                 pr_debug("nf_ct_q931: Q.931 signal %d\n",
1089                          pdu->h323_message_body.choice);
1090                 break;
1091         }
1092
1093         if (ret < 0)
1094                 return -1;
1095
1096         if (pdu->options & eH323_UU_PDU_h245Control) {
1097                 for (i = 0; i < pdu->h245Control.count; i++) {
1098                         ret = process_h245(skb, ct, ctinfo, data, dataoff,
1099                                            &pdu->h245Control.item[i]);
1100                         if (ret < 0)
1101                                 return -1;
1102                 }
1103         }
1104
1105         return 0;
1106 }
1107
1108 /****************************************************************************/
1109 static int q931_help(struct sk_buff *skb, unsigned int protoff,
1110                      struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1111 {
1112         static Q931 q931;
1113         unsigned char *data = NULL;
1114         int datalen;
1115         int dataoff;
1116         int ret;
1117
1118         /* Until there's been traffic both ways, don't look in packets. */
1119         if (ctinfo != IP_CT_ESTABLISHED &&
1120             ctinfo != IP_CT_ESTABLISHED + IP_CT_IS_REPLY) {
1121                 return NF_ACCEPT;
1122         }
1123         pr_debug("nf_ct_q931: skblen = %u\n", skb->len);
1124
1125         spin_lock_bh(&nf_h323_lock);
1126
1127         /* Process each TPKT */
1128         while (get_tpkt_data(skb, protoff, ct, ctinfo,
1129                              &data, &datalen, &dataoff)) {
1130                 pr_debug("nf_ct_q931: TPKT len=%d ", datalen);
1131                 NF_CT_DUMP_TUPLE(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1132
1133                 /* Decode Q.931 signal */
1134                 ret = DecodeQ931(data, datalen, &q931);
1135                 if (ret < 0) {
1136                         pr_debug("nf_ct_q931: decoding error: %s\n",
1137                                  ret == H323_ERROR_BOUND ?
1138                                  "out of bound" : "out of range");
1139                         /* We don't drop when decoding error */
1140                         break;
1141                 }
1142
1143                 /* Process Q.931 signal */
1144                 if (process_q931(skb, ct, ctinfo, &data, dataoff, &q931) < 0)
1145                         goto drop;
1146         }
1147
1148         spin_unlock_bh(&nf_h323_lock);
1149         return NF_ACCEPT;
1150
1151       drop:
1152         spin_unlock_bh(&nf_h323_lock);
1153         if (net_ratelimit())
1154                 printk("nf_ct_q931: packet dropped\n");
1155         return NF_DROP;
1156 }
1157
1158 /****************************************************************************/
1159 static struct nf_conntrack_helper nf_conntrack_helper_q931[] __read_mostly = {
1160         {
1161                 .name                   = "Q.931",
1162                 .me                     = THIS_MODULE,
1163                                           /* T.120 and H.245 */
1164                 .max_expected           = H323_RTP_CHANNEL_MAX * 4 + 4,
1165                 .timeout                = 240,
1166                 .tuple.src.l3num        = AF_INET,
1167                 .tuple.src.u.tcp.port   = __constant_htons(Q931_PORT),
1168                 .tuple.dst.protonum     = IPPROTO_TCP,
1169                 .help                   = q931_help
1170         },
1171         {
1172                 .name                   = "Q.931",
1173                 .me                     = THIS_MODULE,
1174                                           /* T.120 and H.245 */
1175                 .max_expected           = H323_RTP_CHANNEL_MAX * 4 + 4,
1176                 .timeout                = 240,
1177                 .tuple.src.l3num        = AF_INET6,
1178                 .tuple.src.u.tcp.port   = __constant_htons(Q931_PORT),
1179                 .tuple.dst.protonum     = IPPROTO_TCP,
1180                 .help                   = q931_help
1181         },
1182 };
1183
1184 /****************************************************************************/
1185 static unsigned char *get_udp_data(struct sk_buff *skb, unsigned int protoff,
1186                                    int *datalen)
1187 {
1188         const struct udphdr *uh;
1189         struct udphdr _uh;
1190         int dataoff;
1191
1192         uh = skb_header_pointer(skb, protoff, sizeof(_uh), &_uh);
1193         if (uh == NULL)
1194                 return NULL;
1195         dataoff = protoff + sizeof(_uh);
1196         if (dataoff >= skb->len)
1197                 return NULL;
1198         *datalen = skb->len - dataoff;
1199         return skb_header_pointer(skb, dataoff, *datalen, h323_buffer);
1200 }
1201
1202 /****************************************************************************/
1203 static struct nf_conntrack_expect *find_expect(struct nf_conn *ct,
1204                                                union nf_inet_addr *addr,
1205                                                __be16 port)
1206 {
1207         struct nf_conntrack_expect *exp;
1208         struct nf_conntrack_tuple tuple;
1209
1210         memset(&tuple.src.u3, 0, sizeof(tuple.src.u3));
1211         tuple.src.u.tcp.port = 0;
1212         memcpy(&tuple.dst.u3, addr, sizeof(tuple.dst.u3));
1213         tuple.dst.u.tcp.port = port;
1214         tuple.dst.protonum = IPPROTO_TCP;
1215
1216         exp = __nf_ct_expect_find(&tuple);
1217         if (exp && exp->master == ct)
1218                 return exp;
1219         return NULL;
1220 }
1221
1222 /****************************************************************************/
1223 static int set_expect_timeout(struct nf_conntrack_expect *exp,
1224                               unsigned timeout)
1225 {
1226         if (!exp || !del_timer(&exp->timeout))
1227                 return 0;
1228
1229         exp->timeout.expires = jiffies + timeout * HZ;
1230         add_timer(&exp->timeout);
1231
1232         return 1;
1233 }
1234
1235 /****************************************************************************/
1236 static int expect_q931(struct sk_buff *skb, struct nf_conn *ct,
1237                        enum ip_conntrack_info ctinfo,
1238                        unsigned char **data,
1239                        TransportAddress *taddr, int count)
1240 {
1241         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1242         int dir = CTINFO2DIR(ctinfo);
1243         int ret = 0;
1244         int i;
1245         __be16 port;
1246         union nf_inet_addr addr;
1247         struct nf_conntrack_expect *exp;
1248         typeof(nat_q931_hook) nat_q931;
1249
1250         /* Look for the first related address */
1251         for (i = 0; i < count; i++) {
1252                 if (get_h225_addr(ct, *data, &taddr[i], &addr, &port) &&
1253                     memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3,
1254                            sizeof(addr)) == 0 && port != 0)
1255                         break;
1256         }
1257
1258         if (i >= count)         /* Not found */
1259                 return 0;
1260
1261         /* Create expect for Q.931 */
1262         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1263                 return -1;
1264         nf_ct_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num,
1265                           gkrouted_only ? /* only accept calls from GK? */
1266                                 &ct->tuplehash[!dir].tuple.src.u3 : NULL,
1267                           &ct->tuplehash[!dir].tuple.dst.u3,
1268                           IPPROTO_TCP, NULL, &port);
1269         exp->helper = nf_conntrack_helper_q931;
1270         exp->flags = NF_CT_EXPECT_PERMANENT;    /* Accept multiple calls */
1271
1272         nat_q931 = rcu_dereference(nat_q931_hook);
1273         if (nat_q931 && ct->status & IPS_NAT_MASK) {    /* Need NAT */
1274                 ret = nat_q931(skb, ct, ctinfo, data, taddr, i, port, exp);
1275         } else {                /* Conntrack only */
1276                 if (nf_ct_expect_related(exp) == 0) {
1277                         pr_debug("nf_ct_ras: expect Q.931 ");
1278                         NF_CT_DUMP_TUPLE(&exp->tuple);
1279
1280                         /* Save port for looking up expect in processing RCF */
1281                         info->sig_port[dir] = port;
1282                 } else
1283                         ret = -1;
1284         }
1285
1286         nf_ct_expect_put(exp);
1287
1288         return ret;
1289 }
1290
1291 /****************************************************************************/
1292 static int process_grq(struct sk_buff *skb, struct nf_conn *ct,
1293                        enum ip_conntrack_info ctinfo,
1294                        unsigned char **data, GatekeeperRequest *grq)
1295 {
1296         typeof(set_ras_addr_hook) set_ras_addr;
1297
1298         pr_debug("nf_ct_ras: GRQ\n");
1299
1300         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1301         if (set_ras_addr && ct->status & IPS_NAT_MASK)  /* NATed */
1302                 return set_ras_addr(skb, ct, ctinfo, data,
1303                                     &grq->rasAddress, 1);
1304         return 0;
1305 }
1306
1307 /****************************************************************************/
1308 static int process_gcf(struct sk_buff *skb, struct nf_conn *ct,
1309                        enum ip_conntrack_info ctinfo,
1310                        unsigned char **data, GatekeeperConfirm *gcf)
1311 {
1312         int dir = CTINFO2DIR(ctinfo);
1313         int ret = 0;
1314         __be16 port;
1315         union nf_inet_addr addr;
1316         struct nf_conntrack_expect *exp;
1317
1318         pr_debug("nf_ct_ras: GCF\n");
1319
1320         if (!get_h225_addr(ct, *data, &gcf->rasAddress, &addr, &port))
1321                 return 0;
1322
1323         /* Registration port is the same as discovery port */
1324         if (!memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1325             port == ct->tuplehash[dir].tuple.src.u.udp.port)
1326                 return 0;
1327
1328         /* Avoid RAS expectation loops. A GCF is never expected. */
1329         if (test_bit(IPS_EXPECTED_BIT, &ct->status))
1330                 return 0;
1331
1332         /* Need new expect */
1333         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1334                 return -1;
1335         nf_ct_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num,
1336                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1337                           IPPROTO_UDP, NULL, &port);
1338         exp->helper = nf_conntrack_helper_ras;
1339
1340         if (nf_ct_expect_related(exp) == 0) {
1341                 pr_debug("nf_ct_ras: expect RAS ");
1342                 NF_CT_DUMP_TUPLE(&exp->tuple);
1343         } else
1344                 ret = -1;
1345
1346         nf_ct_expect_put(exp);
1347
1348         return ret;
1349 }
1350
1351 /****************************************************************************/
1352 static int process_rrq(struct sk_buff *skb, struct nf_conn *ct,
1353                        enum ip_conntrack_info ctinfo,
1354                        unsigned char **data, RegistrationRequest *rrq)
1355 {
1356         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1357         int ret;
1358         typeof(set_ras_addr_hook) set_ras_addr;
1359
1360         pr_debug("nf_ct_ras: RRQ\n");
1361
1362         ret = expect_q931(skb, ct, ctinfo, data,
1363                           rrq->callSignalAddress.item,
1364                           rrq->callSignalAddress.count);
1365         if (ret < 0)
1366                 return -1;
1367
1368         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1369         if (set_ras_addr && ct->status & IPS_NAT_MASK) {
1370                 ret = set_ras_addr(skb, ct, ctinfo, data,
1371                                    rrq->rasAddress.item,
1372                                    rrq->rasAddress.count);
1373                 if (ret < 0)
1374                         return -1;
1375         }
1376
1377         if (rrq->options & eRegistrationRequest_timeToLive) {
1378                 pr_debug("nf_ct_ras: RRQ TTL = %u seconds\n", rrq->timeToLive);
1379                 info->timeout = rrq->timeToLive;
1380         } else
1381                 info->timeout = default_rrq_ttl;
1382
1383         return 0;
1384 }
1385
1386 /****************************************************************************/
1387 static int process_rcf(struct sk_buff *skb, struct nf_conn *ct,
1388                        enum ip_conntrack_info ctinfo,
1389                        unsigned char **data, RegistrationConfirm *rcf)
1390 {
1391         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1392         int dir = CTINFO2DIR(ctinfo);
1393         int ret;
1394         struct nf_conntrack_expect *exp;
1395         typeof(set_sig_addr_hook) set_sig_addr;
1396
1397         pr_debug("nf_ct_ras: RCF\n");
1398
1399         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1400         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1401                 ret = set_sig_addr(skb, ct, ctinfo, data,
1402                                         rcf->callSignalAddress.item,
1403                                         rcf->callSignalAddress.count);
1404                 if (ret < 0)
1405                         return -1;
1406         }
1407
1408         if (rcf->options & eRegistrationConfirm_timeToLive) {
1409                 pr_debug("nf_ct_ras: RCF TTL = %u seconds\n", rcf->timeToLive);
1410                 info->timeout = rcf->timeToLive;
1411         }
1412
1413         if (info->timeout > 0) {
1414                 pr_debug("nf_ct_ras: set RAS connection timeout to "
1415                          "%u seconds\n", info->timeout);
1416                 nf_ct_refresh(ct, skb, info->timeout * HZ);
1417
1418                 /* Set expect timeout */
1419                 spin_lock_bh(&nf_conntrack_lock);
1420                 exp = find_expect(ct, &ct->tuplehash[dir].tuple.dst.u3,
1421                                   info->sig_port[!dir]);
1422                 if (exp) {
1423                         pr_debug("nf_ct_ras: set Q.931 expect "
1424                                  "timeout to %u seconds for",
1425                                  info->timeout);
1426                         NF_CT_DUMP_TUPLE(&exp->tuple);
1427                         set_expect_timeout(exp, info->timeout);
1428                 }
1429                 spin_unlock_bh(&nf_conntrack_lock);
1430         }
1431
1432         return 0;
1433 }
1434
1435 /****************************************************************************/
1436 static int process_urq(struct sk_buff *skb, struct nf_conn *ct,
1437                        enum ip_conntrack_info ctinfo,
1438                        unsigned char **data, UnregistrationRequest *urq)
1439 {
1440         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1441         int dir = CTINFO2DIR(ctinfo);
1442         int ret;
1443         typeof(set_sig_addr_hook) set_sig_addr;
1444
1445         pr_debug("nf_ct_ras: URQ\n");
1446
1447         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1448         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1449                 ret = set_sig_addr(skb, ct, ctinfo, data,
1450                                    urq->callSignalAddress.item,
1451                                    urq->callSignalAddress.count);
1452                 if (ret < 0)
1453                         return -1;
1454         }
1455
1456         /* Clear old expect */
1457         nf_ct_remove_expectations(ct);
1458         info->sig_port[dir] = 0;
1459         info->sig_port[!dir] = 0;
1460
1461         /* Give it 30 seconds for UCF or URJ */
1462         nf_ct_refresh(ct, skb, 30 * HZ);
1463
1464         return 0;
1465 }
1466
1467 /****************************************************************************/
1468 static int process_arq(struct sk_buff *skb, struct nf_conn *ct,
1469                        enum ip_conntrack_info ctinfo,
1470                        unsigned char **data, AdmissionRequest *arq)
1471 {
1472         const struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1473         int dir = CTINFO2DIR(ctinfo);
1474         __be16 port;
1475         union nf_inet_addr addr;
1476         typeof(set_h225_addr_hook) set_h225_addr;
1477
1478         pr_debug("nf_ct_ras: ARQ\n");
1479
1480         set_h225_addr = rcu_dereference(set_h225_addr_hook);
1481         if ((arq->options & eAdmissionRequest_destCallSignalAddress) &&
1482             get_h225_addr(ct, *data, &arq->destCallSignalAddress,
1483                           &addr, &port) &&
1484             !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1485             port == info->sig_port[dir] &&
1486             set_h225_addr && ct->status & IPS_NAT_MASK) {
1487                 /* Answering ARQ */
1488                 return set_h225_addr(skb, data, 0,
1489                                      &arq->destCallSignalAddress,
1490                                      &ct->tuplehash[!dir].tuple.dst.u3,
1491                                      info->sig_port[!dir]);
1492         }
1493
1494         if ((arq->options & eAdmissionRequest_srcCallSignalAddress) &&
1495             get_h225_addr(ct, *data, &arq->srcCallSignalAddress,
1496                           &addr, &port) &&
1497             !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1498             set_h225_addr && ct->status & IPS_NAT_MASK) {
1499                 /* Calling ARQ */
1500                 return set_h225_addr(skb, data, 0,
1501                                      &arq->srcCallSignalAddress,
1502                                      &ct->tuplehash[!dir].tuple.dst.u3,
1503                                      port);
1504         }
1505
1506         return 0;
1507 }
1508
1509 /****************************************************************************/
1510 static int process_acf(struct sk_buff *skb, struct nf_conn *ct,
1511                        enum ip_conntrack_info ctinfo,
1512                        unsigned char **data, AdmissionConfirm *acf)
1513 {
1514         int dir = CTINFO2DIR(ctinfo);
1515         int ret = 0;
1516         __be16 port;
1517         union nf_inet_addr addr;
1518         struct nf_conntrack_expect *exp;
1519         typeof(set_sig_addr_hook) set_sig_addr;
1520
1521         pr_debug("nf_ct_ras: ACF\n");
1522
1523         if (!get_h225_addr(ct, *data, &acf->destCallSignalAddress,
1524                            &addr, &port))
1525                 return 0;
1526
1527         if (!memcmp(&addr, &ct->tuplehash[dir].tuple.dst.u3, sizeof(addr))) {
1528                 /* Answering ACF */
1529                 set_sig_addr = rcu_dereference(set_sig_addr_hook);
1530                 if (set_sig_addr && ct->status & IPS_NAT_MASK)
1531                         return set_sig_addr(skb, ct, ctinfo, data,
1532                                             &acf->destCallSignalAddress, 1);
1533                 return 0;
1534         }
1535
1536         /* Need new expect */
1537         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1538                 return -1;
1539         nf_ct_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num,
1540                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1541                           IPPROTO_TCP, NULL, &port);
1542         exp->flags = NF_CT_EXPECT_PERMANENT;
1543         exp->helper = nf_conntrack_helper_q931;
1544
1545         if (nf_ct_expect_related(exp) == 0) {
1546                 pr_debug("nf_ct_ras: expect Q.931 ");
1547                 NF_CT_DUMP_TUPLE(&exp->tuple);
1548         } else
1549                 ret = -1;
1550
1551         nf_ct_expect_put(exp);
1552
1553         return ret;
1554 }
1555
1556 /****************************************************************************/
1557 static int process_lrq(struct sk_buff *skb, struct nf_conn *ct,
1558                        enum ip_conntrack_info ctinfo,
1559                        unsigned char **data, LocationRequest *lrq)
1560 {
1561         typeof(set_ras_addr_hook) set_ras_addr;
1562
1563         pr_debug("nf_ct_ras: LRQ\n");
1564
1565         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1566         if (set_ras_addr && ct->status & IPS_NAT_MASK)
1567                 return set_ras_addr(skb, ct, ctinfo, data,
1568                                     &lrq->replyAddress, 1);
1569         return 0;
1570 }
1571
1572 /****************************************************************************/
1573 static int process_lcf(struct sk_buff *skb, struct nf_conn *ct,
1574                        enum ip_conntrack_info ctinfo,
1575                        unsigned char **data, LocationConfirm *lcf)
1576 {
1577         int dir = CTINFO2DIR(ctinfo);
1578         int ret = 0;
1579         __be16 port;
1580         union nf_inet_addr addr;
1581         struct nf_conntrack_expect *exp;
1582
1583         pr_debug("nf_ct_ras: LCF\n");
1584
1585         if (!get_h225_addr(ct, *data, &lcf->callSignalAddress,
1586                            &addr, &port))
1587                 return 0;
1588
1589         /* Need new expect for call signal */
1590         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1591                 return -1;
1592         nf_ct_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num,
1593                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1594                           IPPROTO_TCP, NULL, &port);
1595         exp->flags = NF_CT_EXPECT_PERMANENT;
1596         exp->helper = nf_conntrack_helper_q931;
1597
1598         if (nf_ct_expect_related(exp) == 0) {
1599                 pr_debug("nf_ct_ras: expect Q.931 ");
1600                 NF_CT_DUMP_TUPLE(&exp->tuple);
1601         } else
1602                 ret = -1;
1603
1604         nf_ct_expect_put(exp);
1605
1606         /* Ignore rasAddress */
1607
1608         return ret;
1609 }
1610
1611 /****************************************************************************/
1612 static int process_irr(struct sk_buff *skb, struct nf_conn *ct,
1613                        enum ip_conntrack_info ctinfo,
1614                        unsigned char **data, InfoRequestResponse *irr)
1615 {
1616         int ret;
1617         typeof(set_ras_addr_hook) set_ras_addr;
1618         typeof(set_sig_addr_hook) set_sig_addr;
1619
1620         pr_debug("nf_ct_ras: IRR\n");
1621
1622         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1623         if (set_ras_addr && ct->status & IPS_NAT_MASK) {
1624                 ret = set_ras_addr(skb, ct, ctinfo, data,
1625                                    &irr->rasAddress, 1);
1626                 if (ret < 0)
1627                         return -1;
1628         }
1629
1630         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1631         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1632                 ret = set_sig_addr(skb, ct, ctinfo, data,
1633                                         irr->callSignalAddress.item,
1634                                         irr->callSignalAddress.count);
1635                 if (ret < 0)
1636                         return -1;
1637         }
1638
1639         return 0;
1640 }
1641
1642 /****************************************************************************/
1643 static int process_ras(struct sk_buff *skb, struct nf_conn *ct,
1644                        enum ip_conntrack_info ctinfo,
1645                        unsigned char **data, RasMessage *ras)
1646 {
1647         switch (ras->choice) {
1648         case eRasMessage_gatekeeperRequest:
1649                 return process_grq(skb, ct, ctinfo, data,
1650                                    &ras->gatekeeperRequest);
1651         case eRasMessage_gatekeeperConfirm:
1652                 return process_gcf(skb, ct, ctinfo, data,
1653                                    &ras->gatekeeperConfirm);
1654         case eRasMessage_registrationRequest:
1655                 return process_rrq(skb, ct, ctinfo, data,
1656                                    &ras->registrationRequest);
1657         case eRasMessage_registrationConfirm:
1658                 return process_rcf(skb, ct, ctinfo, data,
1659                                    &ras->registrationConfirm);
1660         case eRasMessage_unregistrationRequest:
1661                 return process_urq(skb, ct, ctinfo, data,
1662                                    &ras->unregistrationRequest);
1663         case eRasMessage_admissionRequest:
1664                 return process_arq(skb, ct, ctinfo, data,
1665                                    &ras->admissionRequest);
1666         case eRasMessage_admissionConfirm:
1667                 return process_acf(skb, ct, ctinfo, data,
1668                                    &ras->admissionConfirm);
1669         case eRasMessage_locationRequest:
1670                 return process_lrq(skb, ct, ctinfo, data,
1671                                    &ras->locationRequest);
1672         case eRasMessage_locationConfirm:
1673                 return process_lcf(skb, ct, ctinfo, data,
1674                                    &ras->locationConfirm);
1675         case eRasMessage_infoRequestResponse:
1676                 return process_irr(skb, ct, ctinfo, data,
1677                                    &ras->infoRequestResponse);
1678         default:
1679                 pr_debug("nf_ct_ras: RAS message %d\n", ras->choice);
1680                 break;
1681         }
1682
1683         return 0;
1684 }
1685
1686 /****************************************************************************/
1687 static int ras_help(struct sk_buff *skb, unsigned int protoff,
1688                     struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1689 {
1690         static RasMessage ras;
1691         unsigned char *data;
1692         int datalen = 0;
1693         int ret;
1694
1695         pr_debug("nf_ct_ras: skblen = %u\n", skb->len);
1696
1697         spin_lock_bh(&nf_h323_lock);
1698
1699         /* Get UDP data */
1700         data = get_udp_data(skb, protoff, &datalen);
1701         if (data == NULL)
1702                 goto accept;
1703         pr_debug("nf_ct_ras: RAS message len=%d ", datalen);
1704         NF_CT_DUMP_TUPLE(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1705
1706         /* Decode RAS message */
1707         ret = DecodeRasMessage(data, datalen, &ras);
1708         if (ret < 0) {
1709                 pr_debug("nf_ct_ras: decoding error: %s\n",
1710                          ret == H323_ERROR_BOUND ?
1711                          "out of bound" : "out of range");
1712                 goto accept;
1713         }
1714
1715         /* Process RAS message */
1716         if (process_ras(skb, ct, ctinfo, &data, &ras) < 0)
1717                 goto drop;
1718
1719       accept:
1720         spin_unlock_bh(&nf_h323_lock);
1721         return NF_ACCEPT;
1722
1723       drop:
1724         spin_unlock_bh(&nf_h323_lock);
1725         if (net_ratelimit())
1726                 printk("nf_ct_ras: packet dropped\n");
1727         return NF_DROP;
1728 }
1729
1730 /****************************************************************************/
1731 static struct nf_conntrack_helper nf_conntrack_helper_ras[] __read_mostly = {
1732         {
1733                 .name                   = "RAS",
1734                 .me                     = THIS_MODULE,
1735                 .max_expected           = 32,
1736                 .timeout                = 240,
1737                 .tuple.src.l3num        = AF_INET,
1738                 .tuple.src.u.udp.port   = __constant_htons(RAS_PORT),
1739                 .tuple.dst.protonum     = IPPROTO_UDP,
1740                 .help                   = ras_help,
1741         },
1742         {
1743                 .name                   = "RAS",
1744                 .me                     = THIS_MODULE,
1745                 .max_expected           = 32,
1746                 .timeout                = 240,
1747                 .tuple.src.l3num        = AF_INET6,
1748                 .tuple.src.u.udp.port   = __constant_htons(RAS_PORT),
1749                 .tuple.dst.protonum     = IPPROTO_UDP,
1750                 .help                   = ras_help,
1751         },
1752 };
1753
1754 /****************************************************************************/
1755 static void __exit nf_conntrack_h323_fini(void)
1756 {
1757         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[1]);
1758         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1759         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1760         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1761         kfree(h323_buffer);
1762         pr_debug("nf_ct_h323: fini\n");
1763 }
1764
1765 /****************************************************************************/
1766 static int __init nf_conntrack_h323_init(void)
1767 {
1768         int ret;
1769
1770         h323_buffer = kmalloc(65536, GFP_KERNEL);
1771         if (!h323_buffer)
1772                 return -ENOMEM;
1773         ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[0]);
1774         if (ret < 0)
1775                 goto err1;
1776         ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[1]);
1777         if (ret < 0)
1778                 goto err2;
1779         ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[0]);
1780         if (ret < 0)
1781                 goto err3;
1782         ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[1]);
1783         if (ret < 0)
1784                 goto err4;
1785         pr_debug("nf_ct_h323: init success\n");
1786         return 0;
1787
1788 err4:
1789         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1790 err3:
1791         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1792 err2:
1793         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1794 err1:
1795         return ret;
1796 }
1797
1798 /****************************************************************************/
1799 module_init(nf_conntrack_h323_init);
1800 module_exit(nf_conntrack_h323_fini);
1801
1802 EXPORT_SYMBOL_GPL(get_h225_addr);
1803 EXPORT_SYMBOL_GPL(set_h245_addr_hook);
1804 EXPORT_SYMBOL_GPL(set_h225_addr_hook);
1805 EXPORT_SYMBOL_GPL(set_sig_addr_hook);
1806 EXPORT_SYMBOL_GPL(set_ras_addr_hook);
1807 EXPORT_SYMBOL_GPL(nat_rtp_rtcp_hook);
1808 EXPORT_SYMBOL_GPL(nat_t120_hook);
1809 EXPORT_SYMBOL_GPL(nat_h245_hook);
1810 EXPORT_SYMBOL_GPL(nat_callforwarding_hook);
1811 EXPORT_SYMBOL_GPL(nat_q931_hook);
1812
1813 MODULE_AUTHOR("Jing Min Zhao <zhaojingmin@users.sourceforge.net>");
1814 MODULE_DESCRIPTION("H.323 connection tracking helper");
1815 MODULE_LICENSE("GPL");
1816 MODULE_ALIAS("ip_conntrack_h323");