net/netfilter/nf_conntrack_h323_main.c

   1 /*
   2  * H.323 connection tracking helper
   3  *
   4  * Copyright (c) 2006 Jing Min Zhao <zhaojingmin@users.sourceforge.net>
   5  *
   6  * This source code is licensed under General Public License version 2.
   7  *
   8  * Based on the 'brute force' H.323 connection tracking module by
   9  * Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
  10  *
  11  * For more information, please see http://nath323.sourceforge.net/
  12  */
  13
  14 #include <linux/module.h>
  15 #include <linux/moduleparam.h>
  16 #include <linux/ctype.h>
  17 #include <linux/inet.h>
  18 #include <linux/in.h>
  19 #include <linux/ip.h>
  20 #include <linux/slab.h>
  21 #include <linux/udp.h>
  22 #include <linux/tcp.h>
  23 #include <linux/skbuff.h>
  24 #include <net/route.h>
  25 #include <net/ip6_route.h>
  26
  27 #include <net/netfilter/nf_conntrack.h>
  28 #include <net/netfilter/nf_conntrack_core.h>
  29 #include <net/netfilter/nf_conntrack_tuple.h>
  30 #include <net/netfilter/nf_conntrack_expect.h>
  31 #include <net/netfilter/nf_conntrack_ecache.h>
  32 #include <net/netfilter/nf_conntrack_helper.h>
  33 #include <net/netfilter/nf_conntrack_zones.h>
  34 #include <linux/netfilter/nf_conntrack_h323.h>
  35
  36 /* Parameters */
  37 static unsigned int default_rrq_ttl __read_mostly = 300;
  38 module_param(default_rrq_ttl, uint, 0600);
  39 MODULE_PARM_DESC(default_rrq_ttl, "use this TTL if it's missing in RRQ");
  40
  41 static int gkrouted_only __read_mostly = 1;
  42 module_param(gkrouted_only, int, 0600);
  43 MODULE_PARM_DESC(gkrouted_only, "only accept calls from gatekeeper");
  44
  45 static int callforward_filter __read_mostly = 1;
  46 module_param(callforward_filter, bool, 0600);
  47 MODULE_PARM_DESC(callforward_filter, "only create call forwarding expectations "
  48                                      "if both endpoints are on different sides "
  49                                      "(determined by routing information)");
  50
  51 /* Hooks for NAT */
  52 int (*set_h245_addr_hook) (struct sk_buff *skb,
  53                            unsigned char **data, int dataoff,
  54                            H245_TransportAddress *taddr,
  55                            union nf_inet_addr *addr, __be16 port)
  56                            __read_mostly;
  57 int (*set_h225_addr_hook) (struct sk_buff *skb,
  58                            unsigned char **data, int dataoff,
  59                            TransportAddress *taddr,
  60                            union nf_inet_addr *addr, __be16 port)
  61                            __read_mostly;
  62 int (*set_sig_addr_hook) (struct sk_buff *skb,
  63                           struct nf_conn *ct,
  64                           enum ip_conntrack_info ctinfo,
  65                           unsigned char **data,
  66                           TransportAddress *taddr, int count) __read_mostly;
  67 int (*set_ras_addr_hook) (struct sk_buff *skb,
  68                           struct nf_conn *ct,
  69                           enum ip_conntrack_info ctinfo,
  70                           unsigned char **data,
  71                           TransportAddress *taddr, int count) __read_mostly;
  72 int (*nat_rtp_rtcp_hook) (struct sk_buff *skb,
  73                           struct nf_conn *ct,
  74                           enum ip_conntrack_info ctinfo,
  75                           unsigned char **data, int dataoff,
  76                           H245_TransportAddress *taddr,
  77                           __be16 port, __be16 rtp_port,
  78                           struct nf_conntrack_expect *rtp_exp,
  79                           struct nf_conntrack_expect *rtcp_exp) __read_mostly;
  80 int (*nat_t120_hook) (struct sk_buff *skb,
  81                       struct nf_conn *ct,
  82                       enum ip_conntrack_info ctinfo,
  83                       unsigned char **data, int dataoff,
  84                       H245_TransportAddress *taddr, __be16 port,
  85                       struct nf_conntrack_expect *exp) __read_mostly;
  86 int (*nat_h245_hook) (struct sk_buff *skb,
  87                       struct nf_conn *ct,
  88                       enum ip_conntrack_info ctinfo,
  89                       unsigned char **data, int dataoff,
  90                       TransportAddress *taddr, __be16 port,
  91                       struct nf_conntrack_expect *exp) __read_mostly;
  92 int (*nat_callforwarding_hook) (struct sk_buff *skb,
  93                                 struct nf_conn *ct,
  94                                 enum ip_conntrack_info ctinfo,
  95                                 unsigned char **data, int dataoff,
  96                                 TransportAddress *taddr, __be16 port,
  97                                 struct nf_conntrack_expect *exp) __read_mostly;
  98 int (*nat_q931_hook) (struct sk_buff *skb,
  99                       struct nf_conn *ct,
 100                       enum ip_conntrack_info ctinfo,
 101                       unsigned char **data, TransportAddress *taddr, int idx,
 102                       __be16 port, struct nf_conntrack_expect *exp)
 103                       __read_mostly;
 104
 105 static DEFINE_SPINLOCK(nf_h323_lock);
 106 static char *h323_buffer;
 107
 108 static struct nf_conntrack_helper nf_conntrack_helper_h245;
 109 static struct nf_conntrack_helper nf_conntrack_helper_q931[];
 110 static struct nf_conntrack_helper nf_conntrack_helper_ras[];
 111
 112 /****************************************************************************/
 113 static int get_tpkt_data(struct sk_buff *skb, unsigned int protoff,
 114                          struct nf_conn *ct, enum ip_conntrack_info ctinfo,
 115                          unsigned char **data, int *datalen, int *dataoff)
 116 {
 117         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
 118         int dir = CTINFO2DIR(ctinfo);
 119         const struct tcphdr *th;
 120         struct tcphdr _tcph;
 121         int tcpdatalen;
 122         int tcpdataoff;
 123         unsigned char *tpkt;
 124         int tpktlen;
 125         int tpktoff;
 126
 127         /* Get TCP header */
 128         th = skb_header_pointer(skb, protoff, sizeof(_tcph), &_tcph);
 129         if (th == NULL)
 130                 return 0;
 131
 132         /* Get TCP data offset */
 133         tcpdataoff = protoff + th->doff * 4;
 134
 135         /* Get TCP data length */
 136         tcpdatalen = skb->len - tcpdataoff;
 137         if (tcpdatalen <= 0)    /* No TCP data */
 138                 goto clear_out;
 139
 140         if (*data == NULL) {    /* first TPKT */
 141                 /* Get first TPKT pointer */
 142                 tpkt = skb_header_pointer(skb, tcpdataoff, tcpdatalen,
 143                                           h323_buffer);
 144                 BUG_ON(tpkt == NULL);
 145
 146                 /* Validate TPKT identifier */
 147                 if (tcpdatalen < 4 || tpkt[0] != 0x03 || tpkt[1] != 0) {
 148                         /* Netmeeting sends TPKT header and data separately */
 149                         if (info->tpkt_len[dir] > 0) {
 150                                 pr_debug("nf_ct_h323: previous packet "
 151                                          "indicated separate TPKT data of %hu "
 152                                          "bytes\n", info->tpkt_len[dir]);
 153                                 if (info->tpkt_len[dir] <= tcpdatalen) {
 154                                         /* Yes, there was a TPKT header
 155                                          * received */
 156                                         *data = tpkt;
 157                                         *datalen = info->tpkt_len[dir];
 158                                         *dataoff = 0;
 159                                         goto out;
 160                                 }
 161
 162                                 /* Fragmented TPKT */
 163                                 pr_debug("nf_ct_h323: fragmented TPKT\n");
 164                                 goto clear_out;
 165                         }
 166
 167                         /* It is not even a TPKT */
 168                         return 0;
 169                 }
 170                 tpktoff = 0;
 171         } else {                /* Next TPKT */
 172                 tpktoff = *dataoff + *datalen;
 173                 tcpdatalen -= tpktoff;
 174                 if (tcpdatalen <= 4)    /* No more TPKT */
 175                         goto clear_out;
 176                 tpkt = *data + *datalen;
 177
 178                 /* Validate TPKT identifier */
 179                 if (tpkt[0] != 0x03 || tpkt[1] != 0)
 180                         goto clear_out;
 181         }
 182
 183         /* Validate TPKT length */
 184         tpktlen = tpkt[2] * 256 + tpkt[3];
 185         if (tpktlen < 4)
 186                 goto clear_out;
 187         if (tpktlen > tcpdatalen) {
 188                 if (tcpdatalen == 4) {  /* Separate TPKT header */
 189                         /* Netmeeting sends TPKT header and data separately */
 190                         pr_debug("nf_ct_h323: separate TPKT header indicates "
 191                                  "there will be TPKT data of %hu bytes\n",
 192                                  tpktlen - 4);
 193                         info->tpkt_len[dir] = tpktlen - 4;
 194                         return 0;
 195                 }
 196
 197                 pr_debug("nf_ct_h323: incomplete TPKT (fragmented?)\n");
 198                 goto clear_out;
 199         }
 200
 201         /* This is the encapsulated data */
 202         *data = tpkt + 4;
 203         *datalen = tpktlen - 4;
 204         *dataoff = tpktoff + 4;
 205
 206       out:
 207         /* Clear TPKT length */
 208         info->tpkt_len[dir] = 0;
 209         return 1;
 210
 211       clear_out:
 212         info->tpkt_len[dir] = 0;
 213         return 0;
 214 }
 215
 216 /****************************************************************************/
 217 static int get_h245_addr(struct nf_conn *ct, const unsigned char *data,
 218                          H245_TransportAddress *taddr,
 219                          union nf_inet_addr *addr, __be16 *port)
 220 {
 221         const unsigned char *p;
 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 (nf_ct_l3num(ct) != AF_INET)
 230                         return 0;
 231                 p = data + taddr->unicastAddress.iPAddress.network;
 232                 len = 4;
 233                 break;
 234         case eUnicastAddress_iP6Address:
 235                 if (nf_ct_l3num(ct) != AF_INET6)
 236                         return 0;
 237                 p = data + taddr->unicastAddress.iP6Address.network;
 238                 len = 16;
 239                 break;
 240         default:
 241                 return 0;
 242         }
 243
 244         memcpy(addr, p, len);
 245         memset((void *)addr + len, 0, sizeof(*addr) - len);
 246         memcpy(port, p + len, sizeof(__be16));
 247
 248         return 1;
 249 }
 250
 251 /****************************************************************************/
 252 static int expect_rtp_rtcp(struct sk_buff *skb, struct nf_conn *ct,
 253                            enum ip_conntrack_info ctinfo,
 254                            unsigned char **data, int dataoff,
 255                            H245_TransportAddress *taddr)
 256 {
 257         int dir = CTINFO2DIR(ctinfo);
 258         int ret = 0;
 259         __be16 port;
 260         __be16 rtp_port, rtcp_port;
 261         union nf_inet_addr addr;
 262         struct nf_conntrack_expect *rtp_exp;
 263         struct nf_conntrack_expect *rtcp_exp;
 264         typeof(nat_rtp_rtcp_hook) nat_rtp_rtcp;
 265
 266         /* Read RTP or RTCP address */
 267         if (!get_h245_addr(ct, *data, taddr, &addr, &port) ||
 268             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
 269             port == 0)
 270                 return 0;
 271
 272         /* RTP port is even */
 273         port &= htons(~1);
 274         rtp_port = port;
 275         rtcp_port = htons(ntohs(port) + 1);
 276
 277         /* Create expect for RTP */
 278         if ((rtp_exp = nf_ct_expect_alloc(ct)) == NULL)
 279                 return -1;
 280         nf_ct_expect_init(rtp_exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 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, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 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, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 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 && ctinfo != IP_CT_ESTABLISHED_REPLY)
 575                 return NF_ACCEPT;
 576
 577         pr_debug("nf_ct_h245: skblen = %u\n", skb->len);
 578
 579         spin_lock_bh(&nf_h323_lock);
 580
 581         /* Process each TPKT */
 582         while (get_tpkt_data(skb, protoff, ct, ctinfo,
 583                              &data, &datalen, &dataoff)) {
 584                 pr_debug("nf_ct_h245: TPKT len=%d ", datalen);
 585                 nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
 586
 587                 /* Decode H.245 signal */
 588                 ret = DecodeMultimediaSystemControlMessage(data, datalen,
 589                                                            &mscm);
 590                 if (ret < 0) {
 591                         pr_debug("nf_ct_h245: decoding error: %s\n",
 592                                  ret == H323_ERROR_BOUND ?
 593                                  "out of bound" : "out of range");
 594                         /* We don't drop when decoding error */
 595                         break;
 596                 }
 597
 598                 /* Process H.245 signal */
 599                 if (process_h245(skb, ct, ctinfo, &data, dataoff, &mscm) < 0)
 600                         goto drop;
 601         }
 602
 603         spin_unlock_bh(&nf_h323_lock);
 604         return NF_ACCEPT;
 605
 606       drop:
 607         spin_unlock_bh(&nf_h323_lock);
 608         if (net_ratelimit())
 609                 pr_info("nf_ct_h245: packet dropped\n");
 610         return NF_DROP;
 611 }
 612
 613 /****************************************************************************/
 614 static const struct nf_conntrack_expect_policy h245_exp_policy = {
 615         .max_expected   = H323_RTP_CHANNEL_MAX * 4 + 2 /* T.120 */,
 616         .timeout        = 240,
 617 };
 618
 619 static struct nf_conntrack_helper nf_conntrack_helper_h245 __read_mostly = {
 620         .name                   = "H.245",
 621         .me                     = THIS_MODULE,
 622         .tuple.src.l3num        = AF_UNSPEC,
 623         .tuple.dst.protonum     = IPPROTO_UDP,
 624         .help                   = h245_help,
 625         .expect_policy          = &h245_exp_policy,
 626 };
 627
 628 /****************************************************************************/
 629 int get_h225_addr(struct nf_conn *ct, unsigned char *data,
 630                   TransportAddress *taddr,
 631                   union nf_inet_addr *addr, __be16 *port)
 632 {
 633         const unsigned char *p;
 634         int len;
 635
 636         switch (taddr->choice) {
 637         case eTransportAddress_ipAddress:
 638                 if (nf_ct_l3num(ct) != AF_INET)
 639                         return 0;
 640                 p = data + taddr->ipAddress.ip;
 641                 len = 4;
 642                 break;
 643         case eTransportAddress_ip6Address:
 644                 if (nf_ct_l3num(ct) != AF_INET6)
 645                         return 0;
 646                 p = data + taddr->ip6Address.ip;
 647                 len = 16;
 648                 break;
 649         default:
 650                 return 0;
 651         }
 652
 653         memcpy(addr, p, len);
 654         memset((void *)addr + len, 0, sizeof(*addr) - len);
 655         memcpy(port, p + len, sizeof(__be16));
 656
 657         return 1;
 658 }
 659
 660 /****************************************************************************/
 661 static int expect_h245(struct sk_buff *skb, struct nf_conn *ct,
 662                        enum ip_conntrack_info ctinfo,
 663                        unsigned char **data, int dataoff,
 664                        TransportAddress *taddr)
 665 {
 666         int dir = CTINFO2DIR(ctinfo);
 667         int ret = 0;
 668         __be16 port;
 669         union nf_inet_addr addr;
 670         struct nf_conntrack_expect *exp;
 671         typeof(nat_h245_hook) nat_h245;
 672
 673         /* Read h245Address */
 674         if (!get_h225_addr(ct, *data, taddr, &addr, &port) ||
 675             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
 676             port == 0)
 677                 return 0;
 678
 679         /* Create expect for h245 connection */
 680         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
 681                 return -1;
 682         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 683                           &ct->tuplehash[!dir].tuple.src.u3,
 684                           &ct->tuplehash[!dir].tuple.dst.u3,
 685                           IPPROTO_TCP, NULL, &port);
 686         exp->helper = &nf_conntrack_helper_h245;
 687
 688         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 689                    &ct->tuplehash[!dir].tuple.dst.u3,
 690                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 691             (nat_h245 = rcu_dereference(nat_h245_hook)) &&
 692             ct->status & IPS_NAT_MASK) {
 693                 /* NAT needed */
 694                 ret = nat_h245(skb, ct, ctinfo, data, dataoff, taddr,
 695                                port, exp);
 696         } else {                /* Conntrack only */
 697                 if (nf_ct_expect_related(exp) == 0) {
 698                         pr_debug("nf_ct_q931: expect H.245 ");
 699                         nf_ct_dump_tuple(&exp->tuple);
 700                 } else
 701                         ret = -1;
 702         }
 703
 704         nf_ct_expect_put(exp);
 705
 706         return ret;
 707 }
 708
 709 /* If the calling party is on the same side of the forward-to party,
 710  * we don't need to track the second call */
 711 static int callforward_do_filter(const union nf_inet_addr *src,
 712                                  const union nf_inet_addr *dst,
 713                                  u_int8_t family)
 714 {
 715         const struct nf_afinfo *afinfo;
 716         int ret = 0;
 717
 718         /* rcu_read_lock()ed by nf_hook_slow() */
 719         afinfo = nf_get_afinfo(family);
 720         if (!afinfo)
 721                 return 0;
 722
 723         switch (family) {
 724         case AF_INET: {
 725                 struct flowi4 fl1, fl2;
 726                 struct rtable *rt1, *rt2;
 727
 728                 memset(&fl1, 0, sizeof(fl1));
 729                 fl1.daddr = src->ip;
 730
 731                 memset(&fl2, 0, sizeof(fl2));
 732                 fl2.daddr = dst->ip;
 733                 if (!afinfo->route(&init_net, (struct dst_entry **)&rt1,
 734                                    flowi4_to_flowi(&fl1), false)) {
 735                         if (!afinfo->route(&init_net, (struct dst_entry **)&rt2,
 736                                            flowi4_to_flowi(&fl2), false)) {
 737                                 if (rt1->rt_gateway == rt2->rt_gateway &&
 738                                     rt1->dst.dev  == rt2->dst.dev)
 739                                         ret = 1;
 740                                 dst_release(&rt2->dst);
 741                         }
 742                         dst_release(&rt1->dst);
 743                 }
 744                 break;
 745         }
 746 #if defined(CONFIG_NF_CONNTRACK_IPV6) || \
 747     defined(CONFIG_NF_CONNTRACK_IPV6_MODULE)
 748         case AF_INET6: {
 749                 struct flowi6 fl1, fl2;
 750                 struct rt6_info *rt1, *rt2;
 751
 752                 memset(&fl1, 0, sizeof(fl1));
 753                 ipv6_addr_copy(&fl1.daddr, &src->in6);
 754
 755                 memset(&fl2, 0, sizeof(fl2));
 756                 ipv6_addr_copy(&fl2.daddr, &dst->in6);
 757                 if (!afinfo->route(&init_net, (struct dst_entry **)&rt1,
 758                                    flowi6_to_flowi(&fl1), false)) {
 759                         if (!afinfo->route(&init_net, (struct dst_entry **)&rt2,
 760                                            flowi6_to_flowi(&fl2), false)) {
 761                                 if (!memcmp(&rt1->rt6i_gateway, &rt2->rt6i_gateway,
 762                                             sizeof(rt1->rt6i_gateway)) &&
 763                                     rt1->dst.dev == rt2->dst.dev)
 764                                         ret = 1;
 765                                 dst_release(&rt2->dst);
 766                         }
 767                         dst_release(&rt1->dst);
 768                 }
 769                 break;
 770         }
 771 #endif
 772         }
 773         return ret;
 774
 775 }
 776
 777 /****************************************************************************/
 778 static int expect_callforwarding(struct sk_buff *skb,
 779                                  struct nf_conn *ct,
 780                                  enum ip_conntrack_info ctinfo,
 781                                  unsigned char **data, int dataoff,
 782                                  TransportAddress *taddr)
 783 {
 784         int dir = CTINFO2DIR(ctinfo);
 785         int ret = 0;
 786         __be16 port;
 787         union nf_inet_addr addr;
 788         struct nf_conntrack_expect *exp;
 789         typeof(nat_callforwarding_hook) nat_callforwarding;
 790
 791         /* Read alternativeAddress */
 792         if (!get_h225_addr(ct, *data, taddr, &addr, &port) || port == 0)
 793                 return 0;
 794
 795         /* If the calling party is on the same side of the forward-to party,
 796          * we don't need to track the second call */
 797         if (callforward_filter &&
 798             callforward_do_filter(&addr, &ct->tuplehash[!dir].tuple.src.u3,
 799                                   nf_ct_l3num(ct))) {
 800                 pr_debug("nf_ct_q931: Call Forwarding not tracked\n");
 801                 return 0;
 802         }
 803
 804         /* Create expect for the second call leg */
 805         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
 806                 return -1;
 807         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 808                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
 809                           IPPROTO_TCP, NULL, &port);
 810         exp->helper = nf_conntrack_helper_q931;
 811
 812         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 813                    &ct->tuplehash[!dir].tuple.dst.u3,
 814                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 815             (nat_callforwarding = rcu_dereference(nat_callforwarding_hook)) &&
 816             ct->status & IPS_NAT_MASK) {
 817                 /* Need NAT */
 818                 ret = nat_callforwarding(skb, ct, ctinfo, data, dataoff,
 819                                          taddr, port, exp);
 820         } else {                /* Conntrack only */
 821                 if (nf_ct_expect_related(exp) == 0) {
 822                         pr_debug("nf_ct_q931: expect Call Forwarding ");
 823                         nf_ct_dump_tuple(&exp->tuple);
 824                 } else
 825                         ret = -1;
 826         }
 827
 828         nf_ct_expect_put(exp);
 829
 830         return ret;
 831 }
 832
 833 /****************************************************************************/
 834 static int process_setup(struct sk_buff *skb, struct nf_conn *ct,
 835                          enum ip_conntrack_info ctinfo,
 836                          unsigned char **data, int dataoff,
 837                          Setup_UUIE *setup)
 838 {
 839         int dir = CTINFO2DIR(ctinfo);
 840         int ret;
 841         int i;
 842         __be16 port;
 843         union nf_inet_addr addr;
 844         typeof(set_h225_addr_hook) set_h225_addr;
 845
 846         pr_debug("nf_ct_q931: Setup\n");
 847
 848         if (setup->options & eSetup_UUIE_h245Address) {
 849                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
 850                                   &setup->h245Address);
 851                 if (ret < 0)
 852                         return -1;
 853         }
 854
 855         set_h225_addr = rcu_dereference(set_h225_addr_hook);
 856         if ((setup->options & eSetup_UUIE_destCallSignalAddress) &&
 857             (set_h225_addr) && ct->status & IPS_NAT_MASK &&
 858             get_h225_addr(ct, *data, &setup->destCallSignalAddress,
 859                           &addr, &port) &&
 860             memcmp(&addr, &ct->tuplehash[!dir].tuple.src.u3, sizeof(addr))) {
 861                 pr_debug("nf_ct_q931: set destCallSignalAddress %pI6:%hu->%pI6:%hu\n",
 862                          &addr, ntohs(port), &ct->tuplehash[!dir].tuple.src.u3,
 863                          ntohs(ct->tuplehash[!dir].tuple.src.u.tcp.port));
 864                 ret = set_h225_addr(skb, data, dataoff,
 865                                     &setup->destCallSignalAddress,
 866                                     &ct->tuplehash[!dir].tuple.src.u3,
 867                                     ct->tuplehash[!dir].tuple.src.u.tcp.port);
 868                 if (ret < 0)
 869                         return -1;
 870         }
 871
 872         if ((setup->options & eSetup_UUIE_sourceCallSignalAddress) &&
 873             (set_h225_addr) && ct->status & IPS_NAT_MASK &&
 874             get_h225_addr(ct, *data, &setup->sourceCallSignalAddress,
 875                           &addr, &port) &&
 876             memcmp(&addr, &ct->tuplehash[!dir].tuple.dst.u3, sizeof(addr))) {
 877                 pr_debug("nf_ct_q931: set sourceCallSignalAddress %pI6:%hu->%pI6:%hu\n",
 878                          &addr, ntohs(port), &ct->tuplehash[!dir].tuple.dst.u3,
 879                          ntohs(ct->tuplehash[!dir].tuple.dst.u.tcp.port));
 880                 ret = set_h225_addr(skb, data, dataoff,
 881                                     &setup->sourceCallSignalAddress,
 882                                     &ct->tuplehash[!dir].tuple.dst.u3,
 883                                     ct->tuplehash[!dir].tuple.dst.u.tcp.port);
 884                 if (ret < 0)
 885                         return -1;
 886         }
 887
 888         if (setup->options & eSetup_UUIE_fastStart) {
 889                 for (i = 0; i < setup->fastStart.count; i++) {
 890                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
 891                                           &setup->fastStart.item[i]);
 892                         if (ret < 0)
 893                                 return -1;
 894                 }
 895         }
 896
 897         return 0;
 898 }
 899
 900 /****************************************************************************/
 901 static int process_callproceeding(struct sk_buff *skb,
 902                                   struct nf_conn *ct,
 903                                   enum ip_conntrack_info ctinfo,
 904                                   unsigned char **data, int dataoff,
 905                                   CallProceeding_UUIE *callproc)
 906 {
 907         int ret;
 908         int i;
 909
 910         pr_debug("nf_ct_q931: CallProceeding\n");
 911
 912         if (callproc->options & eCallProceeding_UUIE_h245Address) {
 913                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
 914                                   &callproc->h245Address);
 915                 if (ret < 0)
 916                         return -1;
 917         }
 918
 919         if (callproc->options & eCallProceeding_UUIE_fastStart) {
 920                 for (i = 0; i < callproc->fastStart.count; i++) {
 921                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
 922                                           &callproc->fastStart.item[i]);
 923                         if (ret < 0)
 924                                 return -1;
 925                 }
 926         }
 927
 928         return 0;
 929 }
 930
 931 /****************************************************************************/
 932 static int process_connect(struct sk_buff *skb, struct nf_conn *ct,
 933                            enum ip_conntrack_info ctinfo,
 934                            unsigned char **data, int dataoff,
 935                            Connect_UUIE *connect)
 936 {
 937         int ret;
 938         int i;
 939
 940         pr_debug("nf_ct_q931: Connect\n");
 941
 942         if (connect->options & eConnect_UUIE_h245Address) {
 943                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
 944                                   &connect->h245Address);
 945                 if (ret < 0)
 946                         return -1;
 947         }
 948
 949         if (connect->options & eConnect_UUIE_fastStart) {
 950                 for (i = 0; i < connect->fastStart.count; i++) {
 951                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
 952                                           &connect->fastStart.item[i]);
 953                         if (ret < 0)
 954                                 return -1;
 955                 }
 956         }
 957
 958         return 0;
 959 }
 960
 961 /****************************************************************************/
 962 static int process_alerting(struct sk_buff *skb, struct nf_conn *ct,
 963                             enum ip_conntrack_info ctinfo,
 964                             unsigned char **data, int dataoff,
 965                             Alerting_UUIE *alert)
 966 {
 967         int ret;
 968         int i;
 969
 970         pr_debug("nf_ct_q931: Alerting\n");
 971
 972         if (alert->options & eAlerting_UUIE_h245Address) {
 973                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
 974                                   &alert->h245Address);
 975                 if (ret < 0)
 976                         return -1;
 977         }
 978
 979         if (alert->options & eAlerting_UUIE_fastStart) {
 980                 for (i = 0; i < alert->fastStart.count; i++) {
 981                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
 982                                           &alert->fastStart.item[i]);
 983                         if (ret < 0)
 984                                 return -1;
 985                 }
 986         }
 987
 988         return 0;
 989 }
 990
 991 /****************************************************************************/
 992 static int process_facility(struct sk_buff *skb, struct nf_conn *ct,
 993                             enum ip_conntrack_info ctinfo,
 994                             unsigned char **data, int dataoff,
 995                             Facility_UUIE *facility)
 996 {
 997         int ret;
 998         int i;
 999
1000         pr_debug("nf_ct_q931: Facility\n");
1001
1002         if (facility->reason.choice == eFacilityReason_callForwarded) {
1003                 if (facility->options & eFacility_UUIE_alternativeAddress)
1004                         return expect_callforwarding(skb, ct, ctinfo, data,
1005                                                      dataoff,
1006                                                      &facility->
1007                                                      alternativeAddress);
1008                 return 0;
1009         }
1010
1011         if (facility->options & eFacility_UUIE_h245Address) {
1012                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
1013                                   &facility->h245Address);
1014                 if (ret < 0)
1015                         return -1;
1016         }
1017
1018         if (facility->options & eFacility_UUIE_fastStart) {
1019                 for (i = 0; i < facility->fastStart.count; i++) {
1020                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
1021                                           &facility->fastStart.item[i]);
1022                         if (ret < 0)
1023                                 return -1;
1024                 }
1025         }
1026
1027         return 0;
1028 }
1029
1030 /****************************************************************************/
1031 static int process_progress(struct sk_buff *skb, struct nf_conn *ct,
1032                             enum ip_conntrack_info ctinfo,
1033                             unsigned char **data, int dataoff,
1034                             Progress_UUIE *progress)
1035 {
1036         int ret;
1037         int i;
1038
1039         pr_debug("nf_ct_q931: Progress\n");
1040
1041         if (progress->options & eProgress_UUIE_h245Address) {
1042                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
1043                                   &progress->h245Address);
1044                 if (ret < 0)
1045                         return -1;
1046         }
1047
1048         if (progress->options & eProgress_UUIE_fastStart) {
1049                 for (i = 0; i < progress->fastStart.count; i++) {
1050                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
1051                                           &progress->fastStart.item[i]);
1052                         if (ret < 0)
1053                                 return -1;
1054                 }
1055         }
1056
1057         return 0;
1058 }
1059
1060 /****************************************************************************/
1061 static int process_q931(struct sk_buff *skb, struct nf_conn *ct,
1062                         enum ip_conntrack_info ctinfo,
1063                         unsigned char **data, int dataoff, Q931 *q931)
1064 {
1065         H323_UU_PDU *pdu = &q931->UUIE.h323_uu_pdu;
1066         int i;
1067         int ret = 0;
1068
1069         switch (pdu->h323_message_body.choice) {
1070         case eH323_UU_PDU_h323_message_body_setup:
1071                 ret = process_setup(skb, ct, ctinfo, data, dataoff,
1072                                     &pdu->h323_message_body.setup);
1073                 break;
1074         case eH323_UU_PDU_h323_message_body_callProceeding:
1075                 ret = process_callproceeding(skb, ct, ctinfo, data, dataoff,
1076                                              &pdu->h323_message_body.
1077                                              callProceeding);
1078                 break;
1079         case eH323_UU_PDU_h323_message_body_connect:
1080                 ret = process_connect(skb, ct, ctinfo, data, dataoff,
1081                                       &pdu->h323_message_body.connect);
1082                 break;
1083         case eH323_UU_PDU_h323_message_body_alerting:
1084                 ret = process_alerting(skb, ct, ctinfo, data, dataoff,
1085                                        &pdu->h323_message_body.alerting);
1086                 break;
1087         case eH323_UU_PDU_h323_message_body_facility:
1088                 ret = process_facility(skb, ct, ctinfo, data, dataoff,
1089                                        &pdu->h323_message_body.facility);
1090                 break;
1091         case eH323_UU_PDU_h323_message_body_progress:
1092                 ret = process_progress(skb, ct, ctinfo, data, dataoff,
1093                                        &pdu->h323_message_body.progress);
1094                 break;
1095         default:
1096                 pr_debug("nf_ct_q931: Q.931 signal %d\n",
1097                          pdu->h323_message_body.choice);
1098                 break;
1099         }
1100
1101         if (ret < 0)
1102                 return -1;
1103
1104         if (pdu->options & eH323_UU_PDU_h245Control) {
1105                 for (i = 0; i < pdu->h245Control.count; i++) {
1106                         ret = process_h245(skb, ct, ctinfo, data, dataoff,
1107                                            &pdu->h245Control.item[i]);
1108                         if (ret < 0)
1109                                 return -1;
1110                 }
1111         }
1112
1113         return 0;
1114 }
1115
1116 /****************************************************************************/
1117 static int q931_help(struct sk_buff *skb, unsigned int protoff,
1118                      struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1119 {
1120         static Q931 q931;
1121         unsigned char *data = NULL;
1122         int datalen;
1123         int dataoff;
1124         int ret;
1125
1126         /* Until there's been traffic both ways, don't look in packets. */
1127         if (ctinfo != IP_CT_ESTABLISHED && ctinfo != IP_CT_ESTABLISHED_REPLY)
1128                 return NF_ACCEPT;
1129
1130         pr_debug("nf_ct_q931: skblen = %u\n", skb->len);
1131
1132         spin_lock_bh(&nf_h323_lock);
1133
1134         /* Process each TPKT */
1135         while (get_tpkt_data(skb, protoff, ct, ctinfo,
1136                              &data, &datalen, &dataoff)) {
1137                 pr_debug("nf_ct_q931: TPKT len=%d ", datalen);
1138                 nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1139
1140                 /* Decode Q.931 signal */
1141                 ret = DecodeQ931(data, datalen, &q931);
1142                 if (ret < 0) {
1143                         pr_debug("nf_ct_q931: decoding error: %s\n",
1144                                  ret == H323_ERROR_BOUND ?
1145                                  "out of bound" : "out of range");
1146                         /* We don't drop when decoding error */
1147                         break;
1148                 }
1149
1150                 /* Process Q.931 signal */
1151                 if (process_q931(skb, ct, ctinfo, &data, dataoff, &q931) < 0)
1152                         goto drop;
1153         }
1154
1155         spin_unlock_bh(&nf_h323_lock);
1156         return NF_ACCEPT;
1157
1158       drop:
1159         spin_unlock_bh(&nf_h323_lock);
1160         if (net_ratelimit())
1161                 pr_info("nf_ct_q931: packet dropped\n");
1162         return NF_DROP;
1163 }
1164
1165 /****************************************************************************/
1166 static const struct nf_conntrack_expect_policy q931_exp_policy = {
1167         /* T.120 and H.245 */
1168         .max_expected           = H323_RTP_CHANNEL_MAX * 4 + 4,
1169         .timeout                = 240,
1170 };
1171
1172 static struct nf_conntrack_helper nf_conntrack_helper_q931[] __read_mostly = {
1173         {
1174                 .name                   = "Q.931",
1175                 .me                     = THIS_MODULE,
1176                 .tuple.src.l3num        = AF_INET,
1177                 .tuple.src.u.tcp.port   = cpu_to_be16(Q931_PORT),
1178                 .tuple.dst.protonum     = IPPROTO_TCP,
1179                 .help                   = q931_help,
1180                 .expect_policy          = &q931_exp_policy,
1181         },
1182         {
1183                 .name                   = "Q.931",
1184                 .me                     = THIS_MODULE,
1185                 .tuple.src.l3num        = AF_INET6,
1186                 .tuple.src.u.tcp.port   = cpu_to_be16(Q931_PORT),
1187                 .tuple.dst.protonum     = IPPROTO_TCP,
1188                 .help                   = q931_help,
1189                 .expect_policy          = &q931_exp_policy,
1190         },
1191 };
1192
1193 /****************************************************************************/
1194 static unsigned char *get_udp_data(struct sk_buff *skb, unsigned int protoff,
1195                                    int *datalen)
1196 {
1197         const struct udphdr *uh;
1198         struct udphdr _uh;
1199         int dataoff;
1200
1201         uh = skb_header_pointer(skb, protoff, sizeof(_uh), &_uh);
1202         if (uh == NULL)
1203                 return NULL;
1204         dataoff = protoff + sizeof(_uh);
1205         if (dataoff >= skb->len)
1206                 return NULL;
1207         *datalen = skb->len - dataoff;
1208         return skb_header_pointer(skb, dataoff, *datalen, h323_buffer);
1209 }
1210
1211 /****************************************************************************/
1212 static struct nf_conntrack_expect *find_expect(struct nf_conn *ct,
1213                                                union nf_inet_addr *addr,
1214                                                __be16 port)
1215 {
1216         struct net *net = nf_ct_net(ct);
1217         struct nf_conntrack_expect *exp;
1218         struct nf_conntrack_tuple tuple;
1219
1220         memset(&tuple.src.u3, 0, sizeof(tuple.src.u3));
1221         tuple.src.u.tcp.port = 0;
1222         memcpy(&tuple.dst.u3, addr, sizeof(tuple.dst.u3));
1223         tuple.dst.u.tcp.port = port;
1224         tuple.dst.protonum = IPPROTO_TCP;
1225
1226         exp = __nf_ct_expect_find(net, nf_ct_zone(ct), &tuple);
1227         if (exp && exp->master == ct)
1228                 return exp;
1229         return NULL;
1230 }
1231
1232 /****************************************************************************/
1233 static int set_expect_timeout(struct nf_conntrack_expect *exp,
1234                               unsigned timeout)
1235 {
1236         if (!exp || !del_timer(&exp->timeout))
1237                 return 0;
1238
1239         exp->timeout.expires = jiffies + timeout * HZ;
1240         add_timer(&exp->timeout);
1241
1242         return 1;
1243 }
1244
1245 /****************************************************************************/
1246 static int expect_q931(struct sk_buff *skb, struct nf_conn *ct,
1247                        enum ip_conntrack_info ctinfo,
1248                        unsigned char **data,
1249                        TransportAddress *taddr, int count)
1250 {
1251         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1252         int dir = CTINFO2DIR(ctinfo);
1253         int ret = 0;
1254         int i;
1255         __be16 port;
1256         union nf_inet_addr addr;
1257         struct nf_conntrack_expect *exp;
1258         typeof(nat_q931_hook) nat_q931;
1259
1260         /* Look for the first related address */
1261         for (i = 0; i < count; i++) {
1262                 if (get_h225_addr(ct, *data, &taddr[i], &addr, &port) &&
1263                     memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3,
1264                            sizeof(addr)) == 0 && port != 0)
1265                         break;
1266         }
1267
1268         if (i >= count)         /* Not found */
1269                 return 0;
1270
1271         /* Create expect for Q.931 */
1272         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1273                 return -1;
1274         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1275                           gkrouted_only ? /* only accept calls from GK? */
1276                                 &ct->tuplehash[!dir].tuple.src.u3 : NULL,
1277                           &ct->tuplehash[!dir].tuple.dst.u3,
1278                           IPPROTO_TCP, NULL, &port);
1279         exp->helper = nf_conntrack_helper_q931;
1280         exp->flags = NF_CT_EXPECT_PERMANENT;    /* Accept multiple calls */
1281
1282         nat_q931 = rcu_dereference(nat_q931_hook);
1283         if (nat_q931 && ct->status & IPS_NAT_MASK) {    /* Need NAT */
1284                 ret = nat_q931(skb, ct, ctinfo, data, taddr, i, port, exp);
1285         } else {                /* Conntrack only */
1286                 if (nf_ct_expect_related(exp) == 0) {
1287                         pr_debug("nf_ct_ras: expect Q.931 ");
1288                         nf_ct_dump_tuple(&exp->tuple);
1289
1290                         /* Save port for looking up expect in processing RCF */
1291                         info->sig_port[dir] = port;
1292                 } else
1293                         ret = -1;
1294         }
1295
1296         nf_ct_expect_put(exp);
1297
1298         return ret;
1299 }
1300
1301 /****************************************************************************/
1302 static int process_grq(struct sk_buff *skb, struct nf_conn *ct,
1303                        enum ip_conntrack_info ctinfo,
1304                        unsigned char **data, GatekeeperRequest *grq)
1305 {
1306         typeof(set_ras_addr_hook) set_ras_addr;
1307
1308         pr_debug("nf_ct_ras: GRQ\n");
1309
1310         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1311         if (set_ras_addr && ct->status & IPS_NAT_MASK)  /* NATed */
1312                 return set_ras_addr(skb, ct, ctinfo, data,
1313                                     &grq->rasAddress, 1);
1314         return 0;
1315 }
1316
1317 /****************************************************************************/
1318 static int process_gcf(struct sk_buff *skb, struct nf_conn *ct,
1319                        enum ip_conntrack_info ctinfo,
1320                        unsigned char **data, GatekeeperConfirm *gcf)
1321 {
1322         int dir = CTINFO2DIR(ctinfo);
1323         int ret = 0;
1324         __be16 port;
1325         union nf_inet_addr addr;
1326         struct nf_conntrack_expect *exp;
1327
1328         pr_debug("nf_ct_ras: GCF\n");
1329
1330         if (!get_h225_addr(ct, *data, &gcf->rasAddress, &addr, &port))
1331                 return 0;
1332
1333         /* Registration port is the same as discovery port */
1334         if (!memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1335             port == ct->tuplehash[dir].tuple.src.u.udp.port)
1336                 return 0;
1337
1338         /* Avoid RAS expectation loops. A GCF is never expected. */
1339         if (test_bit(IPS_EXPECTED_BIT, &ct->status))
1340                 return 0;
1341
1342         /* Need new expect */
1343         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1344                 return -1;
1345         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1346                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1347                           IPPROTO_UDP, NULL, &port);
1348         exp->helper = nf_conntrack_helper_ras;
1349
1350         if (nf_ct_expect_related(exp) == 0) {
1351                 pr_debug("nf_ct_ras: expect RAS ");
1352                 nf_ct_dump_tuple(&exp->tuple);
1353         } else
1354                 ret = -1;
1355
1356         nf_ct_expect_put(exp);
1357
1358         return ret;
1359 }
1360
1361 /****************************************************************************/
1362 static int process_rrq(struct sk_buff *skb, struct nf_conn *ct,
1363                        enum ip_conntrack_info ctinfo,
1364                        unsigned char **data, RegistrationRequest *rrq)
1365 {
1366         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1367         int ret;
1368         typeof(set_ras_addr_hook) set_ras_addr;
1369
1370         pr_debug("nf_ct_ras: RRQ\n");
1371
1372         ret = expect_q931(skb, ct, ctinfo, data,
1373                           rrq->callSignalAddress.item,
1374                           rrq->callSignalAddress.count);
1375         if (ret < 0)
1376                 return -1;
1377
1378         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1379         if (set_ras_addr && ct->status & IPS_NAT_MASK) {
1380                 ret = set_ras_addr(skb, ct, ctinfo, data,
1381                                    rrq->rasAddress.item,
1382                                    rrq->rasAddress.count);
1383                 if (ret < 0)
1384                         return -1;
1385         }
1386
1387         if (rrq->options & eRegistrationRequest_timeToLive) {
1388                 pr_debug("nf_ct_ras: RRQ TTL = %u seconds\n", rrq->timeToLive);
1389                 info->timeout = rrq->timeToLive;
1390         } else
1391                 info->timeout = default_rrq_ttl;
1392
1393         return 0;
1394 }
1395
1396 /****************************************************************************/
1397 static int process_rcf(struct sk_buff *skb, struct nf_conn *ct,
1398                        enum ip_conntrack_info ctinfo,
1399                        unsigned char **data, RegistrationConfirm *rcf)
1400 {
1401         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1402         int dir = CTINFO2DIR(ctinfo);
1403         int ret;
1404         struct nf_conntrack_expect *exp;
1405         typeof(set_sig_addr_hook) set_sig_addr;
1406
1407         pr_debug("nf_ct_ras: RCF\n");
1408
1409         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1410         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1411                 ret = set_sig_addr(skb, ct, ctinfo, data,
1412                                         rcf->callSignalAddress.item,
1413                                         rcf->callSignalAddress.count);
1414                 if (ret < 0)
1415                         return -1;
1416         }
1417
1418         if (rcf->options & eRegistrationConfirm_timeToLive) {
1419                 pr_debug("nf_ct_ras: RCF TTL = %u seconds\n", rcf->timeToLive);
1420                 info->timeout = rcf->timeToLive;
1421         }
1422
1423         if (info->timeout > 0) {
1424                 pr_debug("nf_ct_ras: set RAS connection timeout to "
1425                          "%u seconds\n", info->timeout);
1426                 nf_ct_refresh(ct, skb, info->timeout * HZ);
1427
1428                 /* Set expect timeout */
1429                 spin_lock_bh(&nf_conntrack_lock);
1430                 exp = find_expect(ct, &ct->tuplehash[dir].tuple.dst.u3,
1431                                   info->sig_port[!dir]);
1432                 if (exp) {
1433                         pr_debug("nf_ct_ras: set Q.931 expect "
1434                                  "timeout to %u seconds for",
1435                                  info->timeout);
1436                         nf_ct_dump_tuple(&exp->tuple);
1437                         set_expect_timeout(exp, info->timeout);
1438                 }
1439                 spin_unlock_bh(&nf_conntrack_lock);
1440         }
1441
1442         return 0;
1443 }
1444
1445 /****************************************************************************/
1446 static int process_urq(struct sk_buff *skb, struct nf_conn *ct,
1447                        enum ip_conntrack_info ctinfo,
1448                        unsigned char **data, UnregistrationRequest *urq)
1449 {
1450         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1451         int dir = CTINFO2DIR(ctinfo);
1452         int ret;
1453         typeof(set_sig_addr_hook) set_sig_addr;
1454
1455         pr_debug("nf_ct_ras: URQ\n");
1456
1457         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1458         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1459                 ret = set_sig_addr(skb, ct, ctinfo, data,
1460                                    urq->callSignalAddress.item,
1461                                    urq->callSignalAddress.count);
1462                 if (ret < 0)
1463                         return -1;
1464         }
1465
1466         /* Clear old expect */
1467         nf_ct_remove_expectations(ct);
1468         info->sig_port[dir] = 0;
1469         info->sig_port[!dir] = 0;
1470
1471         /* Give it 30 seconds for UCF or URJ */
1472         nf_ct_refresh(ct, skb, 30 * HZ);
1473
1474         return 0;
1475 }
1476
1477 /****************************************************************************/
1478 static int process_arq(struct sk_buff *skb, struct nf_conn *ct,
1479                        enum ip_conntrack_info ctinfo,
1480                        unsigned char **data, AdmissionRequest *arq)
1481 {
1482         const struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1483         int dir = CTINFO2DIR(ctinfo);
1484         __be16 port;
1485         union nf_inet_addr addr;
1486         typeof(set_h225_addr_hook) set_h225_addr;
1487
1488         pr_debug("nf_ct_ras: ARQ\n");
1489
1490         set_h225_addr = rcu_dereference(set_h225_addr_hook);
1491         if ((arq->options & eAdmissionRequest_destCallSignalAddress) &&
1492             get_h225_addr(ct, *data, &arq->destCallSignalAddress,
1493                           &addr, &port) &&
1494             !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1495             port == info->sig_port[dir] &&
1496             set_h225_addr && ct->status & IPS_NAT_MASK) {
1497                 /* Answering ARQ */
1498                 return set_h225_addr(skb, data, 0,
1499                                      &arq->destCallSignalAddress,
1500                                      &ct->tuplehash[!dir].tuple.dst.u3,
1501                                      info->sig_port[!dir]);
1502         }
1503
1504         if ((arq->options & eAdmissionRequest_srcCallSignalAddress) &&
1505             get_h225_addr(ct, *data, &arq->srcCallSignalAddress,
1506                           &addr, &port) &&
1507             !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1508             set_h225_addr && ct->status & IPS_NAT_MASK) {
1509                 /* Calling ARQ */
1510                 return set_h225_addr(skb, data, 0,
1511                                      &arq->srcCallSignalAddress,
1512                                      &ct->tuplehash[!dir].tuple.dst.u3,
1513                                      port);
1514         }
1515
1516         return 0;
1517 }
1518
1519 /****************************************************************************/
1520 static int process_acf(struct sk_buff *skb, struct nf_conn *ct,
1521                        enum ip_conntrack_info ctinfo,
1522                        unsigned char **data, AdmissionConfirm *acf)
1523 {
1524         int dir = CTINFO2DIR(ctinfo);
1525         int ret = 0;
1526         __be16 port;
1527         union nf_inet_addr addr;
1528         struct nf_conntrack_expect *exp;
1529         typeof(set_sig_addr_hook) set_sig_addr;
1530
1531         pr_debug("nf_ct_ras: ACF\n");
1532
1533         if (!get_h225_addr(ct, *data, &acf->destCallSignalAddress,
1534                            &addr, &port))
1535                 return 0;
1536
1537         if (!memcmp(&addr, &ct->tuplehash[dir].tuple.dst.u3, sizeof(addr))) {
1538                 /* Answering ACF */
1539                 set_sig_addr = rcu_dereference(set_sig_addr_hook);
1540                 if (set_sig_addr && ct->status & IPS_NAT_MASK)
1541                         return set_sig_addr(skb, ct, ctinfo, data,
1542                                             &acf->destCallSignalAddress, 1);
1543                 return 0;
1544         }
1545
1546         /* Need new expect */
1547         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1548                 return -1;
1549         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1550                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1551                           IPPROTO_TCP, NULL, &port);
1552         exp->flags = NF_CT_EXPECT_PERMANENT;
1553         exp->helper = nf_conntrack_helper_q931;
1554
1555         if (nf_ct_expect_related(exp) == 0) {
1556                 pr_debug("nf_ct_ras: expect Q.931 ");
1557                 nf_ct_dump_tuple(&exp->tuple);
1558         } else
1559                 ret = -1;
1560
1561         nf_ct_expect_put(exp);
1562
1563         return ret;
1564 }
1565
1566 /****************************************************************************/
1567 static int process_lrq(struct sk_buff *skb, struct nf_conn *ct,
1568                        enum ip_conntrack_info ctinfo,
1569                        unsigned char **data, LocationRequest *lrq)
1570 {
1571         typeof(set_ras_addr_hook) set_ras_addr;
1572
1573         pr_debug("nf_ct_ras: LRQ\n");
1574
1575         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1576         if (set_ras_addr && ct->status & IPS_NAT_MASK)
1577                 return set_ras_addr(skb, ct, ctinfo, data,
1578                                     &lrq->replyAddress, 1);
1579         return 0;
1580 }
1581
1582 /****************************************************************************/
1583 static int process_lcf(struct sk_buff *skb, struct nf_conn *ct,
1584                        enum ip_conntrack_info ctinfo,
1585                        unsigned char **data, LocationConfirm *lcf)
1586 {
1587         int dir = CTINFO2DIR(ctinfo);
1588         int ret = 0;
1589         __be16 port;
1590         union nf_inet_addr addr;
1591         struct nf_conntrack_expect *exp;
1592
1593         pr_debug("nf_ct_ras: LCF\n");
1594
1595         if (!get_h225_addr(ct, *data, &lcf->callSignalAddress,
1596                            &addr, &port))
1597                 return 0;
1598
1599         /* Need new expect for call signal */
1600         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1601                 return -1;
1602         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1603                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1604                           IPPROTO_TCP, NULL, &port);
1605         exp->flags = NF_CT_EXPECT_PERMANENT;
1606         exp->helper = nf_conntrack_helper_q931;
1607
1608         if (nf_ct_expect_related(exp) == 0) {
1609                 pr_debug("nf_ct_ras: expect Q.931 ");
1610                 nf_ct_dump_tuple(&exp->tuple);
1611         } else
1612                 ret = -1;
1613
1614         nf_ct_expect_put(exp);
1615
1616         /* Ignore rasAddress */
1617
1618         return ret;
1619 }
1620
1621 /****************************************************************************/
1622 static int process_irr(struct sk_buff *skb, struct nf_conn *ct,
1623                        enum ip_conntrack_info ctinfo,
1624                        unsigned char **data, InfoRequestResponse *irr)
1625 {
1626         int ret;
1627         typeof(set_ras_addr_hook) set_ras_addr;
1628         typeof(set_sig_addr_hook) set_sig_addr;
1629
1630         pr_debug("nf_ct_ras: IRR\n");
1631
1632         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1633         if (set_ras_addr && ct->status & IPS_NAT_MASK) {
1634                 ret = set_ras_addr(skb, ct, ctinfo, data,
1635                                    &irr->rasAddress, 1);
1636                 if (ret < 0)
1637                         return -1;
1638         }
1639
1640         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1641         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1642                 ret = set_sig_addr(skb, ct, ctinfo, data,
1643                                         irr->callSignalAddress.item,
1644                                         irr->callSignalAddress.count);
1645                 if (ret < 0)
1646                         return -1;
1647         }
1648
1649         return 0;
1650 }
1651
1652 /****************************************************************************/
1653 static int process_ras(struct sk_buff *skb, struct nf_conn *ct,
1654                        enum ip_conntrack_info ctinfo,
1655                        unsigned char **data, RasMessage *ras)
1656 {
1657         switch (ras->choice) {
1658         case eRasMessage_gatekeeperRequest:
1659                 return process_grq(skb, ct, ctinfo, data,
1660                                    &ras->gatekeeperRequest);
1661         case eRasMessage_gatekeeperConfirm:
1662                 return process_gcf(skb, ct, ctinfo, data,
1663                                    &ras->gatekeeperConfirm);
1664         case eRasMessage_registrationRequest:
1665                 return process_rrq(skb, ct, ctinfo, data,
1666                                    &ras->registrationRequest);
1667         case eRasMessage_registrationConfirm:
1668                 return process_rcf(skb, ct, ctinfo, data,
1669                                    &ras->registrationConfirm);
1670         case eRasMessage_unregistrationRequest:
1671                 return process_urq(skb, ct, ctinfo, data,
1672                                    &ras->unregistrationRequest);
1673         case eRasMessage_admissionRequest:
1674                 return process_arq(skb, ct, ctinfo, data,
1675                                    &ras->admissionRequest);
1676         case eRasMessage_admissionConfirm:
1677                 return process_acf(skb, ct, ctinfo, data,
1678                                    &ras->admissionConfirm);
1679         case eRasMessage_locationRequest:
1680                 return process_lrq(skb, ct, ctinfo, data,
1681                                    &ras->locationRequest);
1682         case eRasMessage_locationConfirm:
1683                 return process_lcf(skb, ct, ctinfo, data,
1684                                    &ras->locationConfirm);
1685         case eRasMessage_infoRequestResponse:
1686                 return process_irr(skb, ct, ctinfo, data,
1687                                    &ras->infoRequestResponse);
1688         default:
1689                 pr_debug("nf_ct_ras: RAS message %d\n", ras->choice);
1690                 break;
1691         }
1692
1693         return 0;
1694 }
1695
1696 /****************************************************************************/
1697 static int ras_help(struct sk_buff *skb, unsigned int protoff,
1698                     struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1699 {
1700         static RasMessage ras;
1701         unsigned char *data;
1702         int datalen = 0;
1703         int ret;
1704
1705         pr_debug("nf_ct_ras: skblen = %u\n", skb->len);
1706
1707         spin_lock_bh(&nf_h323_lock);
1708
1709         /* Get UDP data */
1710         data = get_udp_data(skb, protoff, &datalen);
1711         if (data == NULL)
1712                 goto accept;
1713         pr_debug("nf_ct_ras: RAS message len=%d ", datalen);
1714         nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1715
1716         /* Decode RAS message */
1717         ret = DecodeRasMessage(data, datalen, &ras);
1718         if (ret < 0) {
1719                 pr_debug("nf_ct_ras: decoding error: %s\n",
1720                          ret == H323_ERROR_BOUND ?
1721                          "out of bound" : "out of range");
1722                 goto accept;
1723         }
1724
1725         /* Process RAS message */
1726         if (process_ras(skb, ct, ctinfo, &data, &ras) < 0)
1727                 goto drop;
1728
1729       accept:
1730         spin_unlock_bh(&nf_h323_lock);
1731         return NF_ACCEPT;
1732
1733       drop:
1734         spin_unlock_bh(&nf_h323_lock);
1735         if (net_ratelimit())
1736                 pr_info("nf_ct_ras: packet dropped\n");
1737         return NF_DROP;
1738 }
1739
1740 /****************************************************************************/
1741 static const struct nf_conntrack_expect_policy ras_exp_policy = {
1742         .max_expected           = 32,
1743         .timeout                = 240,
1744 };
1745
1746 static struct nf_conntrack_helper nf_conntrack_helper_ras[] __read_mostly = {
1747         {
1748                 .name                   = "RAS",
1749                 .me                     = THIS_MODULE,
1750                 .tuple.src.l3num        = AF_INET,
1751                 .tuple.src.u.udp.port   = cpu_to_be16(RAS_PORT),
1752                 .tuple.dst.protonum     = IPPROTO_UDP,
1753                 .help                   = ras_help,
1754                 .expect_policy          = &ras_exp_policy,
1755         },
1756         {
1757                 .name                   = "RAS",
1758                 .me                     = THIS_MODULE,
1759                 .tuple.src.l3num        = AF_INET6,
1760                 .tuple.src.u.udp.port   = cpu_to_be16(RAS_PORT),
1761                 .tuple.dst.protonum     = IPPROTO_UDP,
1762                 .help                   = ras_help,
1763                 .expect_policy          = &ras_exp_policy,
1764         },
1765 };
1766
1767 /****************************************************************************/
1768 static void __exit nf_conntrack_h323_fini(void)
1769 {
1770         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[1]);
1771         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1772         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1773         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1774         nf_conntrack_helper_unregister(&nf_conntrack_helper_h245);
1775         kfree(h323_buffer);
1776         pr_debug("nf_ct_h323: fini\n");
1777 }
1778
1779 /****************************************************************************/
1780 static int __init nf_conntrack_h323_init(void)
1781 {
1782         int ret;
1783
1784         h323_buffer = kmalloc(65536, GFP_KERNEL);
1785         if (!h323_buffer)
1786                 return -ENOMEM;
1787         ret = nf_conntrack_helper_register(&nf_conntrack_helper_h245);
1788         if (ret < 0)
1789                 goto err1;
1790         ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[0]);
1791         if (ret < 0)
1792                 goto err2;
1793         ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[1]);
1794         if (ret < 0)
1795                 goto err3;
1796         ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[0]);
1797         if (ret < 0)
1798                 goto err4;
1799         ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[1]);
1800         if (ret < 0)
1801                 goto err5;
1802         pr_debug("nf_ct_h323: init success\n");
1803         return 0;
1804
1805 err5:
1806         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1807 err4:
1808         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1809 err3:
1810         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1811 err2:
1812         nf_conntrack_helper_unregister(&nf_conntrack_helper_h245);
1813 err1:
1814         kfree(h323_buffer);
1815         return ret;
1816 }
1817
1818 /****************************************************************************/
1819 module_init(nf_conntrack_h323_init);
1820 module_exit(nf_conntrack_h323_fini);
1821
1822 EXPORT_SYMBOL_GPL(get_h225_addr);
1823 EXPORT_SYMBOL_GPL(set_h245_addr_hook);
1824 EXPORT_SYMBOL_GPL(set_h225_addr_hook);
1825 EXPORT_SYMBOL_GPL(set_sig_addr_hook);
1826 EXPORT_SYMBOL_GPL(set_ras_addr_hook);
1827 EXPORT_SYMBOL_GPL(nat_rtp_rtcp_hook);
1828 EXPORT_SYMBOL_GPL(nat_t120_hook);
1829 EXPORT_SYMBOL_GPL(nat_h245_hook);
1830 EXPORT_SYMBOL_GPL(nat_callforwarding_hook);
1831 EXPORT_SYMBOL_GPL(nat_q931_hook);
1832
1833 MODULE_AUTHOR("Jing Min Zhao <zhaojingmin@users.sourceforge.net>");
1834 MODULE_DESCRIPTION("H.323 connection tracking helper");
1835 MODULE_LICENSE("GPL");
1836 MODULE_ALIAS("ip_conntrack_h323");
1837 MODULE_ALIAS_NFCT_HELPER("h323");