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 #if 0
  35 #define DEBUGP printk
  36 #else
  37 #define DEBUGP(format, args...)
  38 #endif
  39
  40 /* Parameters */
  41 static unsigned int default_rrq_ttl __read_mostly = 300;
  42 module_param(default_rrq_ttl, uint, 0600);
  43 MODULE_PARM_DESC(default_rrq_ttl, "use this TTL if it's missing in RRQ");
  44
  45 static int gkrouted_only __read_mostly = 1;
  46 module_param(gkrouted_only, int, 0600);
  47 MODULE_PARM_DESC(gkrouted_only, "only accept calls from gatekeeper");
  48
  49 static int callforward_filter __read_mostly = 1;
  50 module_param(callforward_filter, bool, 0600);
  51 MODULE_PARM_DESC(callforward_filter, "only create call forwarding expectations "
  52                                      "if both endpoints are on different sides "
  53                                      "(determined by routing information)");
  54
  55 /* Hooks for NAT */
  56 int (*set_h245_addr_hook) (struct sk_buff **pskb,
  57                            unsigned char **data, int dataoff,
  58                            H245_TransportAddress *taddr,
  59                            union nf_conntrack_address *addr, __be16 port)
  60                            __read_mostly;
  61 int (*set_h225_addr_hook) (struct sk_buff **pskb,
  62                            unsigned char **data, int dataoff,
  63                            TransportAddress *taddr,
  64                            union nf_conntrack_address *addr, __be16 port)
  65                            __read_mostly;
  66 int (*set_sig_addr_hook) (struct sk_buff **pskb,
  67                           struct nf_conn *ct,
  68                           enum ip_conntrack_info ctinfo,
  69                           unsigned char **data,
  70                           TransportAddress *taddr, int count) __read_mostly;
  71 int (*set_ras_addr_hook) (struct sk_buff **pskb,
  72                           struct nf_conn *ct,
  73                           enum ip_conntrack_info ctinfo,
  74                           unsigned char **data,
  75                           TransportAddress *taddr, int count) __read_mostly;
  76 int (*nat_rtp_rtcp_hook) (struct sk_buff **pskb,
  77                           struct nf_conn *ct,
  78                           enum ip_conntrack_info ctinfo,
  79                           unsigned char **data, int dataoff,
  80                           H245_TransportAddress *taddr,
  81                           __be16 port, __be16 rtp_port,
  82                           struct nf_conntrack_expect *rtp_exp,
  83                           struct nf_conntrack_expect *rtcp_exp) __read_mostly;
  84 int (*nat_t120_hook) (struct sk_buff **pskb,
  85                       struct nf_conn *ct,
  86                       enum ip_conntrack_info ctinfo,
  87                       unsigned char **data, int dataoff,
  88                       H245_TransportAddress *taddr, __be16 port,
  89                       struct nf_conntrack_expect *exp) __read_mostly;
  90 int (*nat_h245_hook) (struct sk_buff **pskb,
  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_callforwarding_hook) (struct sk_buff **pskb,
  97                                 struct nf_conn *ct,
  98                                 enum ip_conntrack_info ctinfo,
  99                                 unsigned char **data, int dataoff,
 100                                 TransportAddress *taddr, __be16 port,
 101                                 struct nf_conntrack_expect *exp) __read_mostly;
 102 int (*nat_q931_hook) (struct sk_buff **pskb,
 103                       struct nf_conn *ct,
 104                       enum ip_conntrack_info ctinfo,
 105                       unsigned char **data, TransportAddress *taddr, int idx,
 106                       __be16 port, struct nf_conntrack_expect *exp)
 107                       __read_mostly;
 108
 109 static DEFINE_SPINLOCK(nf_h323_lock);
 110 static char *h323_buffer;
 111
 112 static struct nf_conntrack_helper nf_conntrack_helper_h245;
 113 static struct nf_conntrack_helper nf_conntrack_helper_q931[];
 114 static struct nf_conntrack_helper nf_conntrack_helper_ras[];
 115
 116 /****************************************************************************/
 117 static int get_tpkt_data(struct sk_buff **pskb, unsigned int protoff,
 118                          struct nf_conn *ct, enum ip_conntrack_info ctinfo,
 119                          unsigned char **data, int *datalen, int *dataoff)
 120 {
 121         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
 122         int dir = CTINFO2DIR(ctinfo);
 123         struct tcphdr _tcph, *th;
 124         int tcpdatalen;
 125         int tcpdataoff;
 126         unsigned char *tpkt;
 127         int tpktlen;
 128         int tpktoff;
 129
 130         /* Get TCP header */
 131         th = skb_header_pointer(*pskb, protoff, sizeof(_tcph), &_tcph);
 132         if (th == NULL)
 133                 return 0;
 134
 135         /* Get TCP data offset */
 136         tcpdataoff = protoff + th->doff * 4;
 137
 138         /* Get TCP data length */
 139         tcpdatalen = (*pskb)->len - tcpdataoff;
 140         if (tcpdatalen <= 0)    /* No TCP data */
 141                 goto clear_out;
 142
 143         if (*data == NULL) {    /* first TPKT */
 144                 /* Get first TPKT pointer */
 145                 tpkt = skb_header_pointer(*pskb, tcpdataoff, tcpdatalen,
 146                                           h323_buffer);
 147                 BUG_ON(tpkt == NULL);
 148
 149                 /* Validate TPKT identifier */
 150                 if (tcpdatalen < 4 || tpkt[0] != 0x03 || tpkt[1] != 0) {
 151                         /* Netmeeting sends TPKT header and data separately */
 152                         if (info->tpkt_len[dir] > 0) {
 153                                 DEBUGP("nf_ct_h323: previous packet "
 154                                        "indicated separate TPKT data of %hu "
 155                                        "bytes\n", info->tpkt_len[dir]);
 156                                 if (info->tpkt_len[dir] <= tcpdatalen) {
 157                                         /* Yes, there was a TPKT header
 158                                          * received */
 159                                         *data = tpkt;
 160                                         *datalen = info->tpkt_len[dir];
 161                                         *dataoff = 0;
 162                                         goto out;
 163                                 }
 164
 165                                 /* Fragmented TPKT */
 166                                 if (net_ratelimit())
 167                                         printk("nf_ct_h323: "
 168                                                "fragmented TPKT\n");
 169                                 goto clear_out;
 170                         }
 171
 172                         /* It is not even a TPKT */
 173                         return 0;
 174                 }
 175                 tpktoff = 0;
 176         } else {                /* Next TPKT */
 177                 tpktoff = *dataoff + *datalen;
 178                 tcpdatalen -= tpktoff;
 179                 if (tcpdatalen <= 4)    /* No more TPKT */
 180                         goto clear_out;
 181                 tpkt = *data + *datalen;
 182
 183                 /* Validate TPKT identifier */
 184                 if (tpkt[0] != 0x03 || tpkt[1] != 0)
 185                         goto clear_out;
 186         }
 187
 188         /* Validate TPKT length */
 189         tpktlen = tpkt[2] * 256 + tpkt[3];
 190         if (tpktlen < 4)
 191                 goto clear_out;
 192         if (tpktlen > tcpdatalen) {
 193                 if (tcpdatalen == 4) {  /* Separate TPKT header */
 194                         /* Netmeeting sends TPKT header and data separately */
 195                         DEBUGP("nf_ct_h323: separate TPKT header indicates "
 196                                "there will be TPKT data of %hu bytes\n",
 197                                tpktlen - 4);
 198                         info->tpkt_len[dir] = tpktlen - 4;
 199                         return 0;
 200                 }
 201
 202                 if (net_ratelimit())
 203                         printk("nf_ct_h323: incomplete TPKT (fragmented?)\n");
 204                 goto clear_out;
 205         }
 206
 207         /* This is the encapsulated data */
 208         *data = tpkt + 4;
 209         *datalen = tpktlen - 4;
 210         *dataoff = tpktoff + 4;
 211
 212       out:
 213         /* Clear TPKT length */
 214         info->tpkt_len[dir] = 0;
 215         return 1;
 216
 217       clear_out:
 218         info->tpkt_len[dir] = 0;
 219         return 0;
 220 }
 221
 222 /****************************************************************************/
 223 static int get_h245_addr(struct nf_conn *ct, unsigned char *data,
 224                          H245_TransportAddress *taddr,
 225                          union nf_conntrack_address *addr, __be16 *port)
 226 {
 227         unsigned char *p;
 228         int family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 229         int len;
 230
 231         if (taddr->choice != eH245_TransportAddress_unicastAddress)
 232                 return 0;
 233
 234         switch (taddr->unicastAddress.choice) {
 235         case eUnicastAddress_iPAddress:
 236                 if (family != AF_INET)
 237                         return 0;
 238                 p = data + taddr->unicastAddress.iPAddress.network;
 239                 len = 4;
 240                 break;
 241         case eUnicastAddress_iP6Address:
 242                 if (family != AF_INET6)
 243                         return 0;
 244                 p = data + taddr->unicastAddress.iP6Address.network;
 245                 len = 16;
 246                 break;
 247         default:
 248                 return 0;
 249         }
 250
 251         memcpy(addr, p, len);
 252         memset((void *)addr + len, 0, sizeof(*addr) - len);
 253         memcpy(port, p + len, sizeof(__be16));
 254
 255         return 1;
 256 }
 257
 258 /****************************************************************************/
 259 static int expect_rtp_rtcp(struct sk_buff **pskb, struct nf_conn *ct,
 260                            enum ip_conntrack_info ctinfo,
 261                            unsigned char **data, int dataoff,
 262                            H245_TransportAddress *taddr)
 263 {
 264         int dir = CTINFO2DIR(ctinfo);
 265         int ret = 0;
 266         __be16 port;
 267         __be16 rtp_port, rtcp_port;
 268         union nf_conntrack_address addr;
 269         struct nf_conntrack_expect *rtp_exp;
 270         struct nf_conntrack_expect *rtcp_exp;
 271         typeof(nat_rtp_rtcp_hook) nat_rtp_rtcp;
 272
 273         /* Read RTP or RTCP address */
 274         if (!get_h245_addr(ct, *data, taddr, &addr, &port) ||
 275             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
 276             port == 0)
 277                 return 0;
 278
 279         /* RTP port is even */
 280         port &= htons(~1);
 281         rtp_port = port;
 282         rtcp_port = htons(ntohs(port) + 1);
 283
 284         /* Create expect for RTP */
 285         if ((rtp_exp = nf_ct_expect_alloc(ct)) == NULL)
 286                 return -1;
 287         nf_ct_expect_init(rtp_exp, ct->tuplehash[!dir].tuple.src.l3num,
 288                           &ct->tuplehash[!dir].tuple.src.u3,
 289                           &ct->tuplehash[!dir].tuple.dst.u3,
 290                           IPPROTO_UDP, NULL, &rtp_port);
 291
 292         /* Create expect for RTCP */
 293         if ((rtcp_exp = nf_ct_expect_alloc(ct)) == NULL) {
 294                 nf_ct_expect_put(rtp_exp);
 295                 return -1;
 296         }
 297         nf_ct_expect_init(rtcp_exp, ct->tuplehash[!dir].tuple.src.l3num,
 298                           &ct->tuplehash[!dir].tuple.src.u3,
 299                           &ct->tuplehash[!dir].tuple.dst.u3,
 300                           IPPROTO_UDP, NULL, &rtcp_port);
 301
 302         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 303                    &ct->tuplehash[!dir].tuple.dst.u3,
 304                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 305                    (nat_rtp_rtcp = rcu_dereference(nat_rtp_rtcp_hook)) &&
 306                    ct->status & IPS_NAT_MASK) {
 307                 /* NAT needed */
 308                 ret = nat_rtp_rtcp(pskb, ct, ctinfo, data, dataoff,
 309                                    taddr, port, rtp_port, rtp_exp, rtcp_exp);
 310         } else {                /* Conntrack only */
 311                 if (nf_ct_expect_related(rtp_exp) == 0) {
 312                         if (nf_ct_expect_related(rtcp_exp) == 0) {
 313                                 DEBUGP("nf_ct_h323: expect RTP ");
 314                                 NF_CT_DUMP_TUPLE(&rtp_exp->tuple);
 315                                 DEBUGP("nf_ct_h323: expect RTCP ");
 316                                 NF_CT_DUMP_TUPLE(&rtcp_exp->tuple);
 317                         } else {
 318                                 nf_ct_unexpect_related(rtp_exp);
 319                                 ret = -1;
 320                         }
 321                 } else
 322                         ret = -1;
 323         }
 324
 325         nf_ct_expect_put(rtp_exp);
 326         nf_ct_expect_put(rtcp_exp);
 327
 328         return ret;
 329 }
 330
 331 /****************************************************************************/
 332 static int expect_t120(struct sk_buff **pskb,
 333                        struct nf_conn *ct,
 334                        enum ip_conntrack_info ctinfo,
 335                        unsigned char **data, int dataoff,
 336                        H245_TransportAddress *taddr)
 337 {
 338         int dir = CTINFO2DIR(ctinfo);
 339         int ret = 0;
 340         __be16 port;
 341         union nf_conntrack_address addr;
 342         struct nf_conntrack_expect *exp;
 343         typeof(nat_t120_hook) nat_t120;
 344
 345         /* Read T.120 address */
 346         if (!get_h245_addr(ct, *data, taddr, &addr, &port) ||
 347             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
 348             port == 0)
 349                 return 0;
 350
 351         /* Create expect for T.120 connections */
 352         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
 353                 return -1;
 354         nf_ct_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num,
 355                           &ct->tuplehash[!dir].tuple.src.u3,
 356                           &ct->tuplehash[!dir].tuple.dst.u3,
 357                           IPPROTO_TCP, NULL, &port);
 358         exp->flags = NF_CT_EXPECT_PERMANENT;    /* Accept multiple channels */
 359
 360         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 361                    &ct->tuplehash[!dir].tuple.dst.u3,
 362                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 363             (nat_t120 = rcu_dereference(nat_t120_hook)) &&
 364             ct->status & IPS_NAT_MASK) {
 365                 /* NAT needed */
 366                 ret = nat_t120(pskb, ct, ctinfo, data, dataoff, taddr,
 367                                port, exp);
 368         } else {                /* Conntrack only */
 369                 if (nf_ct_expect_related(exp) == 0) {
 370                         DEBUGP("nf_ct_h323: expect T.120 ");
 371                         NF_CT_DUMP_TUPLE(&exp->tuple);
 372                 } else
 373                         ret = -1;
 374         }
 375
 376         nf_ct_expect_put(exp);
 377
 378         return ret;
 379 }
 380
 381 /****************************************************************************/
 382 static int process_h245_channel(struct sk_buff **pskb,
 383                                 struct nf_conn *ct,
 384                                 enum ip_conntrack_info ctinfo,
 385                                 unsigned char **data, int dataoff,
 386                                 H2250LogicalChannelParameters *channel)
 387 {
 388         int ret;
 389
 390         if (channel->options & eH2250LogicalChannelParameters_mediaChannel) {
 391                 /* RTP */
 392                 ret = expect_rtp_rtcp(pskb, ct, ctinfo, data, dataoff,
 393                                       &channel->mediaChannel);
 394                 if (ret < 0)
 395                         return -1;
 396         }
 397
 398         if (channel->
 399             options & eH2250LogicalChannelParameters_mediaControlChannel) {
 400                 /* RTCP */
 401                 ret = expect_rtp_rtcp(pskb, ct, ctinfo, data, dataoff,
 402                                       &channel->mediaControlChannel);
 403                 if (ret < 0)
 404                         return -1;
 405         }
 406
 407         return 0;
 408 }
 409
 410 /****************************************************************************/
 411 static int process_olc(struct sk_buff **pskb, struct nf_conn *ct,
 412                        enum ip_conntrack_info ctinfo,
 413                        unsigned char **data, int dataoff,
 414                        OpenLogicalChannel *olc)
 415 {
 416         int ret;
 417
 418         DEBUGP("nf_ct_h323: OpenLogicalChannel\n");
 419
 420         if (olc->forwardLogicalChannelParameters.multiplexParameters.choice ==
 421             eOpenLogicalChannel_forwardLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters)
 422         {
 423                 ret = process_h245_channel(pskb, ct, ctinfo, data, dataoff,
 424                                            &olc->
 425                                            forwardLogicalChannelParameters.
 426                                            multiplexParameters.
 427                                            h2250LogicalChannelParameters);
 428                 if (ret < 0)
 429                         return -1;
 430         }
 431
 432         if ((olc->options &
 433              eOpenLogicalChannel_reverseLogicalChannelParameters) &&
 434             (olc->reverseLogicalChannelParameters.options &
 435              eOpenLogicalChannel_reverseLogicalChannelParameters_multiplexParameters)
 436             && (olc->reverseLogicalChannelParameters.multiplexParameters.
 437                 choice ==
 438                 eOpenLogicalChannel_reverseLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters))
 439         {
 440                 ret =
 441                     process_h245_channel(pskb, ct, ctinfo, data, dataoff,
 442                                          &olc->
 443                                          reverseLogicalChannelParameters.
 444                                          multiplexParameters.
 445                                          h2250LogicalChannelParameters);
 446                 if (ret < 0)
 447                         return -1;
 448         }
 449
 450         if ((olc->options & eOpenLogicalChannel_separateStack) &&
 451             olc->forwardLogicalChannelParameters.dataType.choice ==
 452             eDataType_data &&
 453             olc->forwardLogicalChannelParameters.dataType.data.application.
 454             choice == eDataApplicationCapability_application_t120 &&
 455             olc->forwardLogicalChannelParameters.dataType.data.application.
 456             t120.choice == eDataProtocolCapability_separateLANStack &&
 457             olc->separateStack.networkAddress.choice ==
 458             eNetworkAccessParameters_networkAddress_localAreaAddress) {
 459                 ret = expect_t120(pskb, ct, ctinfo, data, dataoff,
 460                                   &olc->separateStack.networkAddress.
 461                                   localAreaAddress);
 462                 if (ret < 0)
 463                         return -1;
 464         }
 465
 466         return 0;
 467 }
 468
 469 /****************************************************************************/
 470 static int process_olca(struct sk_buff **pskb, struct nf_conn *ct,
 471                         enum ip_conntrack_info ctinfo,
 472                         unsigned char **data, int dataoff,
 473                         OpenLogicalChannelAck *olca)
 474 {
 475         H2250LogicalChannelAckParameters *ack;
 476         int ret;
 477
 478         DEBUGP("nf_ct_h323: OpenLogicalChannelAck\n");
 479
 480         if ((olca->options &
 481              eOpenLogicalChannelAck_reverseLogicalChannelParameters) &&
 482             (olca->reverseLogicalChannelParameters.options &
 483              eOpenLogicalChannelAck_reverseLogicalChannelParameters_multiplexParameters)
 484             && (olca->reverseLogicalChannelParameters.multiplexParameters.
 485                 choice ==
 486                 eOpenLogicalChannelAck_reverseLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters))
 487         {
 488                 ret = process_h245_channel(pskb, ct, ctinfo, data, dataoff,
 489                                            &olca->
 490                                            reverseLogicalChannelParameters.
 491                                            multiplexParameters.
 492                                            h2250LogicalChannelParameters);
 493                 if (ret < 0)
 494                         return -1;
 495         }
 496
 497         if ((olca->options &
 498              eOpenLogicalChannelAck_forwardMultiplexAckParameters) &&
 499             (olca->forwardMultiplexAckParameters.choice ==
 500              eOpenLogicalChannelAck_forwardMultiplexAckParameters_h2250LogicalChannelAckParameters))
 501         {
 502                 ack = &olca->forwardMultiplexAckParameters.
 503                     h2250LogicalChannelAckParameters;
 504                 if (ack->options &
 505                     eH2250LogicalChannelAckParameters_mediaChannel) {
 506                         /* RTP */
 507                         ret = expect_rtp_rtcp(pskb, ct, ctinfo, data, dataoff,
 508                                               &ack->mediaChannel);
 509                         if (ret < 0)
 510                                 return -1;
 511                 }
 512
 513                 if (ack->options &
 514                     eH2250LogicalChannelAckParameters_mediaControlChannel) {
 515                         /* RTCP */
 516                         ret = expect_rtp_rtcp(pskb, ct, ctinfo, data, dataoff,
 517                                               &ack->mediaControlChannel);
 518                         if (ret < 0)
 519                                 return -1;
 520                 }
 521         }
 522
 523         if ((olca->options & eOpenLogicalChannelAck_separateStack) &&
 524                 olca->separateStack.networkAddress.choice ==
 525                 eNetworkAccessParameters_networkAddress_localAreaAddress) {
 526                 ret = expect_t120(pskb, ct, ctinfo, data, dataoff,
 527                                   &olca->separateStack.networkAddress.
 528                                   localAreaAddress);
 529                 if (ret < 0)
 530                         return -1;
 531         }
 532
 533         return 0;
 534 }
 535
 536 /****************************************************************************/
 537 static int process_h245(struct sk_buff **pskb, struct nf_conn *ct,
 538                         enum ip_conntrack_info ctinfo,
 539                         unsigned char **data, int dataoff,
 540                         MultimediaSystemControlMessage *mscm)
 541 {
 542         switch (mscm->choice) {
 543         case eMultimediaSystemControlMessage_request:
 544                 if (mscm->request.choice ==
 545                     eRequestMessage_openLogicalChannel) {
 546                         return process_olc(pskb, ct, ctinfo, data, dataoff,
 547                                            &mscm->request.openLogicalChannel);
 548                 }
 549                 DEBUGP("nf_ct_h323: H.245 Request %d\n",
 550                        mscm->request.choice);
 551                 break;
 552         case eMultimediaSystemControlMessage_response:
 553                 if (mscm->response.choice ==
 554                     eResponseMessage_openLogicalChannelAck) {
 555                         return process_olca(pskb, ct, ctinfo, data, dataoff,
 556                                             &mscm->response.
 557                                             openLogicalChannelAck);
 558                 }
 559                 DEBUGP("nf_ct_h323: H.245 Response %d\n",
 560                        mscm->response.choice);
 561                 break;
 562         default:
 563                 DEBUGP("nf_ct_h323: H.245 signal %d\n", mscm->choice);
 564                 break;
 565         }
 566
 567         return 0;
 568 }
 569
 570 /****************************************************************************/
 571 static int h245_help(struct sk_buff **pskb, unsigned int protoff,
 572                      struct nf_conn *ct, enum ip_conntrack_info ctinfo)
 573 {
 574         static MultimediaSystemControlMessage mscm;
 575         unsigned char *data = NULL;
 576         int datalen;
 577         int dataoff;
 578         int ret;
 579
 580         /* Until there's been traffic both ways, don't look in packets. */
 581         if (ctinfo != IP_CT_ESTABLISHED &&
 582             ctinfo != IP_CT_ESTABLISHED + IP_CT_IS_REPLY) {
 583                 return NF_ACCEPT;
 584         }
 585         DEBUGP("nf_ct_h245: skblen = %u\n", (*pskb)->len);
 586
 587         spin_lock_bh(&nf_h323_lock);
 588
 589         /* Process each TPKT */
 590         while (get_tpkt_data(pskb, protoff, ct, ctinfo,
 591                              &data, &datalen, &dataoff)) {
 592                 DEBUGP("nf_ct_h245: TPKT len=%d ", datalen);
 593                 NF_CT_DUMP_TUPLE(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
 594
 595                 /* Decode H.245 signal */
 596                 ret = DecodeMultimediaSystemControlMessage(data, datalen,
 597                                                            &mscm);
 598                 if (ret < 0) {
 599                         if (net_ratelimit())
 600                                 printk("nf_ct_h245: decoding error: %s\n",
 601                                        ret == H323_ERROR_BOUND ?
 602                                        "out of bound" : "out of range");
 603                         /* We don't drop when decoding error */
 604                         break;
 605                 }
 606
 607                 /* Process H.245 signal */
 608                 if (process_h245(pskb, ct, ctinfo, &data, dataoff, &mscm) < 0)
 609                         goto drop;
 610         }
 611
 612         spin_unlock_bh(&nf_h323_lock);
 613         return NF_ACCEPT;
 614
 615       drop:
 616         spin_unlock_bh(&nf_h323_lock);
 617         if (net_ratelimit())
 618                 printk("nf_ct_h245: packet dropped\n");
 619         return NF_DROP;
 620 }
 621
 622 /****************************************************************************/
 623 static struct nf_conntrack_helper nf_conntrack_helper_h245 __read_mostly = {
 624         .name                   = "H.245",
 625         .me                     = THIS_MODULE,
 626         .max_expected           = H323_RTP_CHANNEL_MAX * 4 + 2 /* T.120 */,
 627         .timeout                = 240,
 628         .tuple.dst.protonum     = IPPROTO_UDP,
 629         .help                   = h245_help
 630 };
 631
 632 /****************************************************************************/
 633 int get_h225_addr(struct nf_conn *ct, unsigned char *data,
 634                   TransportAddress *taddr,
 635                   union nf_conntrack_address *addr, __be16 *port)
 636 {
 637         unsigned char *p;
 638         int family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
 639         int len;
 640
 641         switch (taddr->choice) {
 642         case eTransportAddress_ipAddress:
 643                 if (family != AF_INET)
 644                         return 0;
 645                 p = data + taddr->ipAddress.ip;
 646                 len = 4;
 647                 break;
 648         case eTransportAddress_ip6Address:
 649                 if (family != AF_INET6)
 650                         return 0;
 651                 p = data + taddr->ip6Address.ip;
 652                 len = 16;
 653                 break;
 654         default:
 655                 return 0;
 656         }
 657
 658         memcpy(addr, p, len);
 659         memset((void *)addr + len, 0, sizeof(*addr) - len);
 660         memcpy(port, p + len, sizeof(__be16));
 661
 662         return 1;
 663 }
 664
 665 /****************************************************************************/
 666 static int expect_h245(struct sk_buff **pskb, struct nf_conn *ct,
 667                        enum ip_conntrack_info ctinfo,
 668                        unsigned char **data, int dataoff,
 669                        TransportAddress *taddr)
 670 {
 671         int dir = CTINFO2DIR(ctinfo);
 672         int ret = 0;
 673         __be16 port;
 674         union nf_conntrack_address addr;
 675         struct nf_conntrack_expect *exp;
 676         typeof(nat_h245_hook) nat_h245;
 677
 678         /* Read h245Address */
 679         if (!get_h225_addr(ct, *data, taddr, &addr, &port) ||
 680             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
 681             port == 0)
 682                 return 0;
 683
 684         /* Create expect for h245 connection */
 685         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
 686                 return -1;
 687         nf_ct_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num,
 688                           &ct->tuplehash[!dir].tuple.src.u3,
 689                           &ct->tuplehash[!dir].tuple.dst.u3,
 690                           IPPROTO_TCP, NULL, &port);
 691         exp->helper = &nf_conntrack_helper_h245;
 692
 693         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 694                    &ct->tuplehash[!dir].tuple.dst.u3,
 695                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 696             (nat_h245 = rcu_dereference(nat_h245_hook)) &&
 697             ct->status & IPS_NAT_MASK) {
 698                 /* NAT needed */
 699                 ret = nat_h245(pskb, ct, ctinfo, data, dataoff, taddr,
 700                                port, exp);
 701         } else {                /* Conntrack only */
 702                 if (nf_ct_expect_related(exp) == 0) {
 703                         DEBUGP("nf_ct_q931: expect H.245 ");
 704                         NF_CT_DUMP_TUPLE(&exp->tuple);
 705                 } else
 706                         ret = -1;
 707         }
 708
 709         nf_ct_expect_put(exp);
 710
 711         return ret;
 712 }
 713
 714 /* If the calling party is on the same side of the forward-to party,
 715  * we don't need to track the second call */
 716 static int callforward_do_filter(union nf_conntrack_address *src,
 717                                  union nf_conntrack_address *dst,
 718                                  int family)
 719 {
 720         struct flowi fl1, fl2;
 721         int ret = 0;
 722
 723         memset(&fl1, 0, sizeof(fl1));
 724         memset(&fl2, 0, sizeof(fl2));
 725
 726         switch (family) {
 727         case AF_INET: {
 728                 struct rtable *rt1, *rt2;
 729
 730                 fl1.fl4_dst = src->ip;
 731                 fl2.fl4_dst = dst->ip;
 732                 if (ip_route_output_key(&rt1, &fl1) == 0) {
 733                         if (ip_route_output_key(&rt2, &fl2) == 0) {
 734                                 if (rt1->rt_gateway == rt2->rt_gateway &&
 735                                     rt1->u.dst.dev  == rt2->u.dst.dev)
 736                                         ret = 1;
 737                                 dst_release(&rt2->u.dst);
 738                         }
 739                         dst_release(&rt1->u.dst);
 740                 }
 741                 break;
 742         }
 743 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 744         case AF_INET6: {
 745                 struct rt6_info *rt1, *rt2;
 746
 747                 memcpy(&fl1.fl6_dst, src, sizeof(fl1.fl6_dst));
 748                 memcpy(&fl2.fl6_dst, dst, sizeof(fl2.fl6_dst));
 749                 rt1 = (struct rt6_info *)ip6_route_output(NULL, &fl1);
 750                 if (rt1) {
 751                         rt2 = (struct rt6_info *)ip6_route_output(NULL, &fl2);
 752                         if (rt2) {
 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 **pskb,
 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_conntrack_address 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                                   ct->tuplehash[!dir].tuple.src.l3num)) {
 792                 DEBUGP("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, ct->tuplehash[!dir].tuple.src.l3num,
 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(pskb, ct, ctinfo, data, dataoff,
 811                                          taddr, port, exp);
 812         } else {                /* Conntrack only */
 813                 if (nf_ct_expect_related(exp) == 0) {
 814                         DEBUGP("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 **pskb, 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_conntrack_address addr;
 836         typeof(set_h225_addr_hook) set_h225_addr;
 837
 838         DEBUGP("nf_ct_q931: Setup\n");
 839
 840         if (setup->options & eSetup_UUIE_h245Address) {
 841                 ret = expect_h245(pskb, 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                 DEBUGP("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(pskb, 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                 DEBUGP("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(pskb, 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(pskb, 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 **pskb,
 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         DEBUGP("nf_ct_q931: CallProceeding\n");
 907
 908         if (callproc->options & eCallProceeding_UUIE_h245Address) {
 909                 ret = expect_h245(pskb, 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(pskb, 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 **pskb, 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         DEBUGP("nf_ct_q931: Connect\n");
 937
 938         if (connect->options & eConnect_UUIE_h245Address) {
 939                 ret = expect_h245(pskb, 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(pskb, 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 **pskb, 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         DEBUGP("nf_ct_q931: Alerting\n");
 967
 968         if (alert->options & eAlerting_UUIE_h245Address) {
 969                 ret = expect_h245(pskb, 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(pskb, 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 **pskb, 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         DEBUGP("nf_ct_q931: Facility\n");
 997
 998         if (facility->reason.choice == eFacilityReason_callForwarded) {
 999                 if (facility->options & eFacility_UUIE_alternativeAddress)
1000                         return expect_callforwarding(pskb, 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(pskb, 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(pskb, 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 **pskb, 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         DEBUGP("nf_ct_q931: Progress\n");
1036
1037         if (progress->options & eProgress_UUIE_h245Address) {
1038                 ret = expect_h245(pskb, 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(pskb, 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 **pskb, 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(pskb, 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(pskb, 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(pskb, 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(pskb, 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(pskb, 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(pskb, ct, ctinfo, data, dataoff,
1089                                        &pdu->h323_message_body.progress);
1090                 break;
1091         default:
1092                 DEBUGP("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(pskb, 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 **pskb, 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         DEBUGP("nf_ct_q931: skblen = %u\n", (*pskb)->len);
1128
1129         spin_lock_bh(&nf_h323_lock);
1130
1131         /* Process each TPKT */
1132         while (get_tpkt_data(pskb, protoff, ct, ctinfo,
1133                              &data, &datalen, &dataoff)) {
1134                 DEBUGP("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                         if (net_ratelimit())
1141                                 printk("nf_ct_q931: decoding error: %s\n",
1142                                        ret == H323_ERROR_BOUND ?
1143                                        "out of bound" : "out of range");
1144                         /* We don't drop when decoding error */
1145                         break;
1146                 }
1147
1148                 /* Process Q.931 signal */
1149                 if (process_q931(pskb, ct, ctinfo, &data, dataoff, &q931) < 0)
1150                         goto drop;
1151         }
1152
1153         spin_unlock_bh(&nf_h323_lock);
1154         return NF_ACCEPT;
1155
1156       drop:
1157         spin_unlock_bh(&nf_h323_lock);
1158         if (net_ratelimit())
1159                 printk("nf_ct_q931: packet dropped\n");
1160         return NF_DROP;
1161 }
1162
1163 /****************************************************************************/
1164 static struct nf_conntrack_helper nf_conntrack_helper_q931[] __read_mostly = {
1165         {
1166                 .name                   = "Q.931",
1167                 .me                     = THIS_MODULE,
1168                                           /* T.120 and H.245 */
1169                 .max_expected           = H323_RTP_CHANNEL_MAX * 4 + 4,
1170                 .timeout                = 240,
1171                 .tuple.src.l3num        = AF_INET,
1172                 .tuple.src.u.tcp.port   = __constant_htons(Q931_PORT),
1173                 .tuple.dst.protonum     = IPPROTO_TCP,
1174                 .help                   = q931_help
1175         },
1176         {
1177                 .name                   = "Q.931",
1178                 .me                     = THIS_MODULE,
1179                                           /* T.120 and H.245 */
1180                 .max_expected           = H323_RTP_CHANNEL_MAX * 4 + 4,
1181                 .timeout                = 240,
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         },
1187 };
1188
1189 /****************************************************************************/
1190 static unsigned char *get_udp_data(struct sk_buff **pskb, unsigned int protoff,
1191                                    int *datalen)
1192 {
1193         struct udphdr _uh, *uh;
1194         int dataoff;
1195
1196         uh = skb_header_pointer(*pskb, protoff, sizeof(_uh), &_uh);
1197         if (uh == NULL)
1198                 return NULL;
1199         dataoff = protoff + sizeof(_uh);
1200         if (dataoff >= (*pskb)->len)
1201                 return NULL;
1202         *datalen = (*pskb)->len - dataoff;
1203         return skb_header_pointer(*pskb, dataoff, *datalen, h323_buffer);
1204 }
1205
1206 /****************************************************************************/
1207 static struct nf_conntrack_expect *find_expect(struct nf_conn *ct,
1208                                                union nf_conntrack_address *addr,
1209                                                __be16 port)
1210 {
1211         struct nf_conntrack_expect *exp;
1212         struct nf_conntrack_tuple tuple;
1213
1214         memset(&tuple.src.u3, 0, sizeof(tuple.src.u3));
1215         tuple.src.u.tcp.port = 0;
1216         memcpy(&tuple.dst.u3, addr, sizeof(tuple.dst.u3));
1217         tuple.dst.u.tcp.port = port;
1218         tuple.dst.protonum = IPPROTO_TCP;
1219
1220         exp = __nf_ct_expect_find(&tuple);
1221         if (exp && exp->master == ct)
1222                 return exp;
1223         return NULL;
1224 }
1225
1226 /****************************************************************************/
1227 static int set_expect_timeout(struct nf_conntrack_expect *exp,
1228                               unsigned timeout)
1229 {
1230         if (!exp || !del_timer(&exp->timeout))
1231                 return 0;
1232
1233         exp->timeout.expires = jiffies + timeout * HZ;
1234         add_timer(&exp->timeout);
1235
1236         return 1;
1237 }
1238
1239 /****************************************************************************/
1240 static int expect_q931(struct sk_buff **pskb, struct nf_conn *ct,
1241                        enum ip_conntrack_info ctinfo,
1242                        unsigned char **data,
1243                        TransportAddress *taddr, int count)
1244 {
1245         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1246         int dir = CTINFO2DIR(ctinfo);
1247         int ret = 0;
1248         int i;
1249         __be16 port;
1250         union nf_conntrack_address addr;
1251         struct nf_conntrack_expect *exp;
1252         typeof(nat_q931_hook) nat_q931;
1253
1254         /* Look for the first related address */
1255         for (i = 0; i < count; i++) {
1256                 if (get_h225_addr(ct, *data, &taddr[i], &addr, &port) &&
1257                     memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3,
1258                            sizeof(addr)) == 0 && port != 0)
1259                         break;
1260         }
1261
1262         if (i >= count)         /* Not found */
1263                 return 0;
1264
1265         /* Create expect for Q.931 */
1266         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1267                 return -1;
1268         nf_ct_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num,
1269                           gkrouted_only ? /* only accept calls from GK? */
1270                                 &ct->tuplehash[!dir].tuple.src.u3 : NULL,
1271                           &ct->tuplehash[!dir].tuple.dst.u3,
1272                           IPPROTO_TCP, NULL, &port);
1273         exp->helper = nf_conntrack_helper_q931;
1274         exp->flags = NF_CT_EXPECT_PERMANENT;    /* Accept multiple calls */
1275
1276         nat_q931 = rcu_dereference(nat_q931_hook);
1277         if (nat_q931 && ct->status & IPS_NAT_MASK) {    /* Need NAT */
1278                 ret = nat_q931(pskb, ct, ctinfo, data, taddr, i, port, exp);
1279         } else {                /* Conntrack only */
1280                 if (nf_ct_expect_related(exp) == 0) {
1281                         DEBUGP("nf_ct_ras: expect Q.931 ");
1282                         NF_CT_DUMP_TUPLE(&exp->tuple);
1283
1284                         /* Save port for looking up expect in processing RCF */
1285                         info->sig_port[dir] = port;
1286                 } else
1287                         ret = -1;
1288         }
1289
1290         nf_ct_expect_put(exp);
1291
1292         return ret;
1293 }
1294
1295 /****************************************************************************/
1296 static int process_grq(struct sk_buff **pskb, struct nf_conn *ct,
1297                        enum ip_conntrack_info ctinfo,
1298                        unsigned char **data, GatekeeperRequest *grq)
1299 {
1300         typeof(set_ras_addr_hook) set_ras_addr;
1301
1302         DEBUGP("nf_ct_ras: GRQ\n");
1303
1304         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1305         if (set_ras_addr && ct->status & IPS_NAT_MASK)  /* NATed */
1306                 return set_ras_addr(pskb, ct, ctinfo, data,
1307                                     &grq->rasAddress, 1);
1308         return 0;
1309 }
1310
1311 /****************************************************************************/
1312 static int process_gcf(struct sk_buff **pskb, struct nf_conn *ct,
1313                        enum ip_conntrack_info ctinfo,
1314                        unsigned char **data, GatekeeperConfirm *gcf)
1315 {
1316         int dir = CTINFO2DIR(ctinfo);
1317         int ret = 0;
1318         __be16 port;
1319         union nf_conntrack_address addr;
1320         struct nf_conntrack_expect *exp;
1321
1322         DEBUGP("nf_ct_ras: GCF\n");
1323
1324         if (!get_h225_addr(ct, *data, &gcf->rasAddress, &addr, &port))
1325                 return 0;
1326
1327         /* Registration port is the same as discovery port */
1328         if (!memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1329             port == ct->tuplehash[dir].tuple.src.u.udp.port)
1330                 return 0;
1331
1332         /* Avoid RAS expectation loops. A GCF is never expected. */
1333         if (test_bit(IPS_EXPECTED_BIT, &ct->status))
1334                 return 0;
1335
1336         /* Need new expect */
1337         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1338                 return -1;
1339         nf_ct_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num,
1340                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1341                           IPPROTO_UDP, NULL, &port);
1342         exp->helper = nf_conntrack_helper_ras;
1343
1344         if (nf_ct_expect_related(exp) == 0) {
1345                 DEBUGP("nf_ct_ras: expect RAS ");
1346                 NF_CT_DUMP_TUPLE(&exp->tuple);
1347         } else
1348                 ret = -1;
1349
1350         nf_ct_expect_put(exp);
1351
1352         return ret;
1353 }
1354
1355 /****************************************************************************/
1356 static int process_rrq(struct sk_buff **pskb, struct nf_conn *ct,
1357                        enum ip_conntrack_info ctinfo,
1358                        unsigned char **data, RegistrationRequest *rrq)
1359 {
1360         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1361         int ret;
1362         typeof(set_ras_addr_hook) set_ras_addr;
1363
1364         DEBUGP("nf_ct_ras: RRQ\n");
1365
1366         ret = expect_q931(pskb, ct, ctinfo, data,
1367                           rrq->callSignalAddress.item,
1368                           rrq->callSignalAddress.count);
1369         if (ret < 0)
1370                 return -1;
1371
1372         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1373         if (set_ras_addr && ct->status & IPS_NAT_MASK) {
1374                 ret = set_ras_addr(pskb, ct, ctinfo, data,
1375                                    rrq->rasAddress.item,
1376                                    rrq->rasAddress.count);
1377                 if (ret < 0)
1378                         return -1;
1379         }
1380
1381         if (rrq->options & eRegistrationRequest_timeToLive) {
1382                 DEBUGP("nf_ct_ras: RRQ TTL = %u seconds\n", rrq->timeToLive);
1383                 info->timeout = rrq->timeToLive;
1384         } else
1385                 info->timeout = default_rrq_ttl;
1386
1387         return 0;
1388 }
1389
1390 /****************************************************************************/
1391 static int process_rcf(struct sk_buff **pskb, struct nf_conn *ct,
1392                        enum ip_conntrack_info ctinfo,
1393                        unsigned char **data, RegistrationConfirm *rcf)
1394 {
1395         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1396         int dir = CTINFO2DIR(ctinfo);
1397         int ret;
1398         struct nf_conntrack_expect *exp;
1399         typeof(set_sig_addr_hook) set_sig_addr;
1400
1401         DEBUGP("nf_ct_ras: RCF\n");
1402
1403         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1404         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1405                 ret = set_sig_addr(pskb, ct, ctinfo, data,
1406                                         rcf->callSignalAddress.item,
1407                                         rcf->callSignalAddress.count);
1408                 if (ret < 0)
1409                         return -1;
1410         }
1411
1412         if (rcf->options & eRegistrationConfirm_timeToLive) {
1413                 DEBUGP("nf_ct_ras: RCF TTL = %u seconds\n", rcf->timeToLive);
1414                 info->timeout = rcf->timeToLive;
1415         }
1416
1417         if (info->timeout > 0) {
1418                 DEBUGP
1419                     ("nf_ct_ras: set RAS connection timeout to %u seconds\n",
1420                      info->timeout);
1421                 nf_ct_refresh(ct, *pskb, info->timeout * HZ);
1422
1423                 /* Set expect timeout */
1424                 read_lock_bh(&nf_conntrack_lock);
1425                 exp = find_expect(ct, &ct->tuplehash[dir].tuple.dst.u3,
1426                                   info->sig_port[!dir]);
1427                 if (exp) {
1428                         DEBUGP("nf_ct_ras: set Q.931 expect "
1429                                "timeout to %u seconds for",
1430                                info->timeout);
1431                         NF_CT_DUMP_TUPLE(&exp->tuple);
1432                         set_expect_timeout(exp, info->timeout);
1433                 }
1434                 read_unlock_bh(&nf_conntrack_lock);
1435         }
1436
1437         return 0;
1438 }
1439
1440 /****************************************************************************/
1441 static int process_urq(struct sk_buff **pskb, struct nf_conn *ct,
1442                        enum ip_conntrack_info ctinfo,
1443                        unsigned char **data, UnregistrationRequest *urq)
1444 {
1445         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1446         int dir = CTINFO2DIR(ctinfo);
1447         int ret;
1448         typeof(set_sig_addr_hook) set_sig_addr;
1449
1450         DEBUGP("nf_ct_ras: URQ\n");
1451
1452         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1453         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1454                 ret = set_sig_addr(pskb, ct, ctinfo, data,
1455                                    urq->callSignalAddress.item,
1456                                    urq->callSignalAddress.count);
1457                 if (ret < 0)
1458                         return -1;
1459         }
1460
1461         /* Clear old expect */
1462         nf_ct_remove_expectations(ct);
1463         info->sig_port[dir] = 0;
1464         info->sig_port[!dir] = 0;
1465
1466         /* Give it 30 seconds for UCF or URJ */
1467         nf_ct_refresh(ct, *pskb, 30 * HZ);
1468
1469         return 0;
1470 }
1471
1472 /****************************************************************************/
1473 static int process_arq(struct sk_buff **pskb, struct nf_conn *ct,
1474                        enum ip_conntrack_info ctinfo,
1475                        unsigned char **data, AdmissionRequest *arq)
1476 {
1477         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1478         int dir = CTINFO2DIR(ctinfo);
1479         __be16 port;
1480         union nf_conntrack_address addr;
1481         typeof(set_h225_addr_hook) set_h225_addr;
1482
1483         DEBUGP("nf_ct_ras: ARQ\n");
1484
1485         set_h225_addr = rcu_dereference(set_h225_addr_hook);
1486         if ((arq->options & eAdmissionRequest_destCallSignalAddress) &&
1487             get_h225_addr(ct, *data, &arq->destCallSignalAddress,
1488                           &addr, &port) &&
1489             !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1490             port == info->sig_port[dir] &&
1491             set_h225_addr && ct->status & IPS_NAT_MASK) {
1492                 /* Answering ARQ */
1493                 return set_h225_addr(pskb, data, 0,
1494                                      &arq->destCallSignalAddress,
1495                                      &ct->tuplehash[!dir].tuple.dst.u3,
1496                                      info->sig_port[!dir]);
1497         }
1498
1499         if ((arq->options & eAdmissionRequest_srcCallSignalAddress) &&
1500             get_h225_addr(ct, *data, &arq->srcCallSignalAddress,
1501                           &addr, &port) &&
1502             !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1503             set_h225_addr && ct->status & IPS_NAT_MASK) {
1504                 /* Calling ARQ */
1505                 return set_h225_addr(pskb, data, 0,
1506                                      &arq->srcCallSignalAddress,
1507                                      &ct->tuplehash[!dir].tuple.dst.u3,
1508                                      port);
1509         }
1510
1511         return 0;
1512 }
1513
1514 /****************************************************************************/
1515 static int process_acf(struct sk_buff **pskb, struct nf_conn *ct,
1516                        enum ip_conntrack_info ctinfo,
1517                        unsigned char **data, AdmissionConfirm *acf)
1518 {
1519         int dir = CTINFO2DIR(ctinfo);
1520         int ret = 0;
1521         __be16 port;
1522         union nf_conntrack_address addr;
1523         struct nf_conntrack_expect *exp;
1524         typeof(set_sig_addr_hook) set_sig_addr;
1525
1526         DEBUGP("nf_ct_ras: ACF\n");
1527
1528         if (!get_h225_addr(ct, *data, &acf->destCallSignalAddress,
1529                            &addr, &port))
1530                 return 0;
1531
1532         if (!memcmp(&addr, &ct->tuplehash[dir].tuple.dst.u3, sizeof(addr))) {
1533                 /* Answering ACF */
1534                 set_sig_addr = rcu_dereference(set_sig_addr_hook);
1535                 if (set_sig_addr && ct->status & IPS_NAT_MASK)
1536                         return set_sig_addr(pskb, ct, ctinfo, data,
1537                                             &acf->destCallSignalAddress, 1);
1538                 return 0;
1539         }
1540
1541         /* Need new expect */
1542         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1543                 return -1;
1544         nf_ct_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num,
1545                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1546                           IPPROTO_TCP, NULL, &port);
1547         exp->flags = NF_CT_EXPECT_PERMANENT;
1548         exp->helper = nf_conntrack_helper_q931;
1549
1550         if (nf_ct_expect_related(exp) == 0) {
1551                 DEBUGP("nf_ct_ras: expect Q.931 ");
1552                 NF_CT_DUMP_TUPLE(&exp->tuple);
1553         } else
1554                 ret = -1;
1555
1556         nf_ct_expect_put(exp);
1557
1558         return ret;
1559 }
1560
1561 /****************************************************************************/
1562 static int process_lrq(struct sk_buff **pskb, struct nf_conn *ct,
1563                        enum ip_conntrack_info ctinfo,
1564                        unsigned char **data, LocationRequest *lrq)
1565 {
1566         typeof(set_ras_addr_hook) set_ras_addr;
1567
1568         DEBUGP("nf_ct_ras: LRQ\n");
1569
1570         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1571         if (set_ras_addr && ct->status & IPS_NAT_MASK)
1572                 return set_ras_addr(pskb, ct, ctinfo, data,
1573                                     &lrq->replyAddress, 1);
1574         return 0;
1575 }
1576
1577 /****************************************************************************/
1578 static int process_lcf(struct sk_buff **pskb, struct nf_conn *ct,
1579                        enum ip_conntrack_info ctinfo,
1580                        unsigned char **data, LocationConfirm *lcf)
1581 {
1582         int dir = CTINFO2DIR(ctinfo);
1583         int ret = 0;
1584         __be16 port;
1585         union nf_conntrack_address addr;
1586         struct nf_conntrack_expect *exp;
1587
1588         DEBUGP("nf_ct_ras: LCF\n");
1589
1590         if (!get_h225_addr(ct, *data, &lcf->callSignalAddress,
1591                            &addr, &port))
1592                 return 0;
1593
1594         /* Need new expect for call signal */
1595         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1596                 return -1;
1597         nf_ct_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num,
1598                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1599                           IPPROTO_TCP, NULL, &port);
1600         exp->flags = NF_CT_EXPECT_PERMANENT;
1601         exp->helper = nf_conntrack_helper_q931;
1602
1603         if (nf_ct_expect_related(exp) == 0) {
1604                 DEBUGP("nf_ct_ras: expect Q.931 ");
1605                 NF_CT_DUMP_TUPLE(&exp->tuple);
1606         } else
1607                 ret = -1;
1608
1609         nf_ct_expect_put(exp);
1610
1611         /* Ignore rasAddress */
1612
1613         return ret;
1614 }
1615
1616 /****************************************************************************/
1617 static int process_irr(struct sk_buff **pskb, struct nf_conn *ct,
1618                        enum ip_conntrack_info ctinfo,
1619                        unsigned char **data, InfoRequestResponse *irr)
1620 {
1621         int ret;
1622         typeof(set_ras_addr_hook) set_ras_addr;
1623         typeof(set_sig_addr_hook) set_sig_addr;
1624
1625         DEBUGP("nf_ct_ras: IRR\n");
1626
1627         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1628         if (set_ras_addr && ct->status & IPS_NAT_MASK) {
1629                 ret = set_ras_addr(pskb, ct, ctinfo, data,
1630                                    &irr->rasAddress, 1);
1631                 if (ret < 0)
1632                         return -1;
1633         }
1634
1635         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1636         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1637                 ret = set_sig_addr(pskb, ct, ctinfo, data,
1638                                         irr->callSignalAddress.item,
1639                                         irr->callSignalAddress.count);
1640                 if (ret < 0)
1641                         return -1;
1642         }
1643
1644         return 0;
1645 }
1646
1647 /****************************************************************************/
1648 static int process_ras(struct sk_buff **pskb, struct nf_conn *ct,
1649                        enum ip_conntrack_info ctinfo,
1650                        unsigned char **data, RasMessage *ras)
1651 {
1652         switch (ras->choice) {
1653         case eRasMessage_gatekeeperRequest:
1654                 return process_grq(pskb, ct, ctinfo, data,
1655                                    &ras->gatekeeperRequest);
1656         case eRasMessage_gatekeeperConfirm:
1657                 return process_gcf(pskb, ct, ctinfo, data,
1658                                    &ras->gatekeeperConfirm);
1659         case eRasMessage_registrationRequest:
1660                 return process_rrq(pskb, ct, ctinfo, data,
1661                                    &ras->registrationRequest);
1662         case eRasMessage_registrationConfirm:
1663                 return process_rcf(pskb, ct, ctinfo, data,
1664                                    &ras->registrationConfirm);
1665         case eRasMessage_unregistrationRequest:
1666                 return process_urq(pskb, ct, ctinfo, data,
1667                                    &ras->unregistrationRequest);
1668         case eRasMessage_admissionRequest:
1669                 return process_arq(pskb, ct, ctinfo, data,
1670                                    &ras->admissionRequest);
1671         case eRasMessage_admissionConfirm:
1672                 return process_acf(pskb, ct, ctinfo, data,
1673                                    &ras->admissionConfirm);
1674         case eRasMessage_locationRequest:
1675                 return process_lrq(pskb, ct, ctinfo, data,
1676                                    &ras->locationRequest);
1677         case eRasMessage_locationConfirm:
1678                 return process_lcf(pskb, ct, ctinfo, data,
1679                                    &ras->locationConfirm);
1680         case eRasMessage_infoRequestResponse:
1681                 return process_irr(pskb, ct, ctinfo, data,
1682                                    &ras->infoRequestResponse);
1683         default:
1684                 DEBUGP("nf_ct_ras: RAS message %d\n", ras->choice);
1685                 break;
1686         }
1687
1688         return 0;
1689 }
1690
1691 /****************************************************************************/
1692 static int ras_help(struct sk_buff **pskb, unsigned int protoff,
1693                     struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1694 {
1695         static RasMessage ras;
1696         unsigned char *data;
1697         int datalen = 0;
1698         int ret;
1699
1700         DEBUGP("nf_ct_ras: skblen = %u\n", (*pskb)->len);
1701
1702         spin_lock_bh(&nf_h323_lock);
1703
1704         /* Get UDP data */
1705         data = get_udp_data(pskb, protoff, &datalen);
1706         if (data == NULL)
1707                 goto accept;
1708         DEBUGP("nf_ct_ras: RAS message len=%d ", datalen);
1709         NF_CT_DUMP_TUPLE(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1710
1711         /* Decode RAS message */
1712         ret = DecodeRasMessage(data, datalen, &ras);
1713         if (ret < 0) {
1714                 if (net_ratelimit())
1715                         printk("nf_ct_ras: decoding error: %s\n",
1716                                ret == H323_ERROR_BOUND ?
1717                                "out of bound" : "out of range");
1718                 goto accept;
1719         }
1720
1721         /* Process RAS message */
1722         if (process_ras(pskb, ct, ctinfo, &data, &ras) < 0)
1723                 goto drop;
1724
1725       accept:
1726         spin_unlock_bh(&nf_h323_lock);
1727         return NF_ACCEPT;
1728
1729       drop:
1730         spin_unlock_bh(&nf_h323_lock);
1731         if (net_ratelimit())
1732                 printk("nf_ct_ras: packet dropped\n");
1733         return NF_DROP;
1734 }
1735
1736 /****************************************************************************/
1737 static struct nf_conntrack_helper nf_conntrack_helper_ras[] __read_mostly = {
1738         {
1739                 .name                   = "RAS",
1740                 .me                     = THIS_MODULE,
1741                 .max_expected           = 32,
1742                 .timeout                = 240,
1743                 .tuple.src.l3num        = AF_INET,
1744                 .tuple.src.u.udp.port   = __constant_htons(RAS_PORT),
1745                 .tuple.dst.protonum     = IPPROTO_UDP,
1746                 .help                   = ras_help,
1747         },
1748         {
1749                 .name                   = "RAS",
1750                 .me                     = THIS_MODULE,
1751                 .max_expected           = 32,
1752                 .timeout                = 240,
1753                 .tuple.src.l3num        = AF_INET6,
1754                 .tuple.src.u.udp.port   = __constant_htons(RAS_PORT),
1755                 .tuple.dst.protonum     = IPPROTO_UDP,
1756                 .help                   = ras_help,
1757         },
1758 };
1759
1760 /****************************************************************************/
1761 static void __exit nf_conntrack_h323_fini(void)
1762 {
1763         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[1]);
1764         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1765         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1766         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1767         kfree(h323_buffer);
1768         DEBUGP("nf_ct_h323: fini\n");
1769 }
1770
1771 /****************************************************************************/
1772 static int __init nf_conntrack_h323_init(void)
1773 {
1774         int ret;
1775
1776         h323_buffer = kmalloc(65536, GFP_KERNEL);
1777         if (!h323_buffer)
1778                 return -ENOMEM;
1779         ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[0]);
1780         if (ret < 0)
1781                 goto err1;
1782         ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[1]);
1783         if (ret < 0)
1784                 goto err2;
1785         ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[0]);
1786         if (ret < 0)
1787                 goto err3;
1788         ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[1]);
1789         if (ret < 0)
1790                 goto err4;
1791         DEBUGP("nf_ct_h323: init success\n");
1792         return 0;
1793
1794 err4:
1795         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1796 err3:
1797         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1798 err2:
1799         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1800 err1:
1801         return ret;
1802 }
1803
1804 /****************************************************************************/
1805 module_init(nf_conntrack_h323_init);
1806 module_exit(nf_conntrack_h323_fini);
1807
1808 EXPORT_SYMBOL_GPL(get_h225_addr);
1809 EXPORT_SYMBOL_GPL(set_h245_addr_hook);
1810 EXPORT_SYMBOL_GPL(set_h225_addr_hook);
1811 EXPORT_SYMBOL_GPL(set_sig_addr_hook);
1812 EXPORT_SYMBOL_GPL(set_ras_addr_hook);
1813 EXPORT_SYMBOL_GPL(nat_rtp_rtcp_hook);
1814 EXPORT_SYMBOL_GPL(nat_t120_hook);
1815 EXPORT_SYMBOL_GPL(nat_h245_hook);
1816 EXPORT_SYMBOL_GPL(nat_callforwarding_hook);
1817 EXPORT_SYMBOL_GPL(nat_q931_hook);
1818
1819 MODULE_AUTHOR("Jing Min Zhao <zhaojingmin@users.sourceforge.net>");
1820 MODULE_DESCRIPTION("H.323 connection tracking helper");
1821 MODULE_LICENSE("GPL");
1822 MODULE_ALIAS("ip_conntrack_h323");