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 bool callforward_filter __read_mostly = true;
  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 IS_ENABLED(CONFIG_NF_CONNTRACK_IPV6)
 747         case AF_INET6: {
 748                 struct flowi6 fl1, fl2;
 749                 struct rt6_info *rt1, *rt2;
 750
 751                 memset(&fl1, 0, sizeof(fl1));
 752                 fl1.daddr = src->in6;
 753
 754                 memset(&fl2, 0, sizeof(fl2));
 755                 fl2.daddr = dst->in6;
 756                 if (!afinfo->route(&init_net, (struct dst_entry **)&rt1,
 757                                    flowi6_to_flowi(&fl1), false)) {
 758                         if (!afinfo->route(&init_net, (struct dst_entry **)&rt2,
 759                                            flowi6_to_flowi(&fl2), false)) {
 760                                 if (!memcmp(&rt1->rt6i_gateway, &rt2->rt6i_gateway,
 761                                             sizeof(rt1->rt6i_gateway)) &&
 762                                     rt1->dst.dev == rt2->dst.dev)
 763                                         ret = 1;
 764                                 dst_release(&rt2->dst);
 765                         }
 766                         dst_release(&rt1->dst);
 767                 }
 768                 break;
 769         }
 770 #endif
 771         }
 772         return ret;
 773
 774 }
 775
 776 /****************************************************************************/
 777 static int expect_callforwarding(struct sk_buff *skb,
 778                                  struct nf_conn *ct,
 779                                  enum ip_conntrack_info ctinfo,
 780                                  unsigned char **data, int dataoff,
 781                                  TransportAddress *taddr)
 782 {
 783         int dir = CTINFO2DIR(ctinfo);
 784         int ret = 0;
 785         __be16 port;
 786         union nf_inet_addr addr;
 787         struct nf_conntrack_expect *exp;
 788         typeof(nat_callforwarding_hook) nat_callforwarding;
 789
 790         /* Read alternativeAddress */
 791         if (!get_h225_addr(ct, *data, taddr, &addr, &port) || port == 0)
 792                 return 0;
 793
 794         /* If the calling party is on the same side of the forward-to party,
 795          * we don't need to track the second call */
 796         if (callforward_filter &&
 797             callforward_do_filter(&addr, &ct->tuplehash[!dir].tuple.src.u3,
 798                                   nf_ct_l3num(ct))) {
 799                 pr_debug("nf_ct_q931: Call Forwarding not tracked\n");
 800                 return 0;
 801         }
 802
 803         /* Create expect for the second call leg */
 804         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
 805                 return -1;
 806         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 807                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
 808                           IPPROTO_TCP, NULL, &port);
 809         exp->helper = nf_conntrack_helper_q931;
 810
 811         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 812                    &ct->tuplehash[!dir].tuple.dst.u3,
 813                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 814             (nat_callforwarding = rcu_dereference(nat_callforwarding_hook)) &&
 815             ct->status & IPS_NAT_MASK) {
 816                 /* Need NAT */
 817                 ret = nat_callforwarding(skb, ct, ctinfo, data, dataoff,
 818                                          taddr, port, exp);
 819         } else {                /* Conntrack only */
 820                 if (nf_ct_expect_related(exp) == 0) {
 821                         pr_debug("nf_ct_q931: expect Call Forwarding ");
 822                         nf_ct_dump_tuple(&exp->tuple);
 823                 } else
 824                         ret = -1;
 825         }
 826
 827         nf_ct_expect_put(exp);
 828
 829         return ret;
 830 }
 831
 832 /****************************************************************************/
 833 static int process_setup(struct sk_buff *skb, struct nf_conn *ct,
 834                          enum ip_conntrack_info ctinfo,
 835                          unsigned char **data, int dataoff,
 836                          Setup_UUIE *setup)
 837 {
 838         int dir = CTINFO2DIR(ctinfo);
 839         int ret;
 840         int i;
 841         __be16 port;
 842         union nf_inet_addr addr;
 843         typeof(set_h225_addr_hook) set_h225_addr;
 844
 845         pr_debug("nf_ct_q931: Setup\n");
 846
 847         if (setup->options & eSetup_UUIE_h245Address) {
 848                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
 849                                   &setup->h245Address);
 850                 if (ret < 0)
 851                         return -1;
 852         }
 853
 854         set_h225_addr = rcu_dereference(set_h225_addr_hook);
 855         if ((setup->options & eSetup_UUIE_destCallSignalAddress) &&
 856             (set_h225_addr) && ct->status & IPS_NAT_MASK &&
 857             get_h225_addr(ct, *data, &setup->destCallSignalAddress,
 858                           &addr, &port) &&
 859             memcmp(&addr, &ct->tuplehash[!dir].tuple.src.u3, sizeof(addr))) {
 860                 pr_debug("nf_ct_q931: set destCallSignalAddress %pI6:%hu->%pI6:%hu\n",
 861                          &addr, ntohs(port), &ct->tuplehash[!dir].tuple.src.u3,
 862                          ntohs(ct->tuplehash[!dir].tuple.src.u.tcp.port));
 863                 ret = set_h225_addr(skb, data, dataoff,
 864                                     &setup->destCallSignalAddress,
 865                                     &ct->tuplehash[!dir].tuple.src.u3,
 866                                     ct->tuplehash[!dir].tuple.src.u.tcp.port);
 867                 if (ret < 0)
 868                         return -1;
 869         }
 870
 871         if ((setup->options & eSetup_UUIE_sourceCallSignalAddress) &&
 872             (set_h225_addr) && ct->status & IPS_NAT_MASK &&
 873             get_h225_addr(ct, *data, &setup->sourceCallSignalAddress,
 874                           &addr, &port) &&
 875             memcmp(&addr, &ct->tuplehash[!dir].tuple.dst.u3, sizeof(addr))) {
 876                 pr_debug("nf_ct_q931: set sourceCallSignalAddress %pI6:%hu->%pI6:%hu\n",
 877                          &addr, ntohs(port), &ct->tuplehash[!dir].tuple.dst.u3,
 878                          ntohs(ct->tuplehash[!dir].tuple.dst.u.tcp.port));
 879                 ret = set_h225_addr(skb, data, dataoff,
 880                                     &setup->sourceCallSignalAddress,
 881                                     &ct->tuplehash[!dir].tuple.dst.u3,
 882                                     ct->tuplehash[!dir].tuple.dst.u.tcp.port);
 883                 if (ret < 0)
 884                         return -1;
 885         }
 886
 887         if (setup->options & eSetup_UUIE_fastStart) {
 888                 for (i = 0; i < setup->fastStart.count; i++) {
 889                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
 890                                           &setup->fastStart.item[i]);
 891                         if (ret < 0)
 892                                 return -1;
 893                 }
 894         }
 895
 896         return 0;
 897 }
 898
 899 /****************************************************************************/
 900 static int process_callproceeding(struct sk_buff *skb,
 901                                   struct nf_conn *ct,
 902                                   enum ip_conntrack_info ctinfo,
 903                                   unsigned char **data, int dataoff,
 904                                   CallProceeding_UUIE *callproc)
 905 {
 906         int ret;
 907         int i;
 908
 909         pr_debug("nf_ct_q931: CallProceeding\n");
 910
 911         if (callproc->options & eCallProceeding_UUIE_h245Address) {
 912                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
 913                                   &callproc->h245Address);
 914                 if (ret < 0)
 915                         return -1;
 916         }
 917
 918         if (callproc->options & eCallProceeding_UUIE_fastStart) {
 919                 for (i = 0; i < callproc->fastStart.count; i++) {
 920                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
 921                                           &callproc->fastStart.item[i]);
 922                         if (ret < 0)
 923                                 return -1;
 924                 }
 925         }
 926
 927         return 0;
 928 }
 929
 930 /****************************************************************************/
 931 static int process_connect(struct sk_buff *skb, struct nf_conn *ct,
 932                            enum ip_conntrack_info ctinfo,
 933                            unsigned char **data, int dataoff,
 934                            Connect_UUIE *connect)
 935 {
 936         int ret;
 937         int i;
 938
 939         pr_debug("nf_ct_q931: Connect\n");
 940
 941         if (connect->options & eConnect_UUIE_h245Address) {
 942                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
 943                                   &connect->h245Address);
 944                 if (ret < 0)
 945                         return -1;
 946         }
 947
 948         if (connect->options & eConnect_UUIE_fastStart) {
 949                 for (i = 0; i < connect->fastStart.count; i++) {
 950                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
 951                                           &connect->fastStart.item[i]);
 952                         if (ret < 0)
 953                                 return -1;
 954                 }
 955         }
 956
 957         return 0;
 958 }
 959
 960 /****************************************************************************/
 961 static int process_alerting(struct sk_buff *skb, struct nf_conn *ct,
 962                             enum ip_conntrack_info ctinfo,
 963                             unsigned char **data, int dataoff,
 964                             Alerting_UUIE *alert)
 965 {
 966         int ret;
 967         int i;
 968
 969         pr_debug("nf_ct_q931: Alerting\n");
 970
 971         if (alert->options & eAlerting_UUIE_h245Address) {
 972                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
 973                                   &alert->h245Address);
 974                 if (ret < 0)
 975                         return -1;
 976         }
 977
 978         if (alert->options & eAlerting_UUIE_fastStart) {
 979                 for (i = 0; i < alert->fastStart.count; i++) {
 980                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
 981                                           &alert->fastStart.item[i]);
 982                         if (ret < 0)
 983                                 return -1;
 984                 }
 985         }
 986
 987         return 0;
 988 }
 989
 990 /****************************************************************************/
 991 static int process_facility(struct sk_buff *skb, struct nf_conn *ct,
 992                             enum ip_conntrack_info ctinfo,
 993                             unsigned char **data, int dataoff,
 994                             Facility_UUIE *facility)
 995 {
 996         int ret;
 997         int i;
 998
 999         pr_debug("nf_ct_q931: Facility\n");
1000
1001         if (facility->reason.choice == eFacilityReason_callForwarded) {
1002                 if (facility->options & eFacility_UUIE_alternativeAddress)
1003                         return expect_callforwarding(skb, ct, ctinfo, data,
1004                                                      dataoff,
1005                                                      &facility->
1006                                                      alternativeAddress);
1007                 return 0;
1008         }
1009
1010         if (facility->options & eFacility_UUIE_h245Address) {
1011                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
1012                                   &facility->h245Address);
1013                 if (ret < 0)
1014                         return -1;
1015         }
1016
1017         if (facility->options & eFacility_UUIE_fastStart) {
1018                 for (i = 0; i < facility->fastStart.count; i++) {
1019                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
1020                                           &facility->fastStart.item[i]);
1021                         if (ret < 0)
1022                                 return -1;
1023                 }
1024         }
1025
1026         return 0;
1027 }
1028
1029 /****************************************************************************/
1030 static int process_progress(struct sk_buff *skb, struct nf_conn *ct,
1031                             enum ip_conntrack_info ctinfo,
1032                             unsigned char **data, int dataoff,
1033                             Progress_UUIE *progress)
1034 {
1035         int ret;
1036         int i;
1037
1038         pr_debug("nf_ct_q931: Progress\n");
1039
1040         if (progress->options & eProgress_UUIE_h245Address) {
1041                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
1042                                   &progress->h245Address);
1043                 if (ret < 0)
1044                         return -1;
1045         }
1046
1047         if (progress->options & eProgress_UUIE_fastStart) {
1048                 for (i = 0; i < progress->fastStart.count; i++) {
1049                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
1050                                           &progress->fastStart.item[i]);
1051                         if (ret < 0)
1052                                 return -1;
1053                 }
1054         }
1055
1056         return 0;
1057 }
1058
1059 /****************************************************************************/
1060 static int process_q931(struct sk_buff *skb, struct nf_conn *ct,
1061                         enum ip_conntrack_info ctinfo,
1062                         unsigned char **data, int dataoff, Q931 *q931)
1063 {
1064         H323_UU_PDU *pdu = &q931->UUIE.h323_uu_pdu;
1065         int i;
1066         int ret = 0;
1067
1068         switch (pdu->h323_message_body.choice) {
1069         case eH323_UU_PDU_h323_message_body_setup:
1070                 ret = process_setup(skb, ct, ctinfo, data, dataoff,
1071                                     &pdu->h323_message_body.setup);
1072                 break;
1073         case eH323_UU_PDU_h323_message_body_callProceeding:
1074                 ret = process_callproceeding(skb, ct, ctinfo, data, dataoff,
1075                                              &pdu->h323_message_body.
1076                                              callProceeding);
1077                 break;
1078         case eH323_UU_PDU_h323_message_body_connect:
1079                 ret = process_connect(skb, ct, ctinfo, data, dataoff,
1080                                       &pdu->h323_message_body.connect);
1081                 break;
1082         case eH323_UU_PDU_h323_message_body_alerting:
1083                 ret = process_alerting(skb, ct, ctinfo, data, dataoff,
1084                                        &pdu->h323_message_body.alerting);
1085                 break;
1086         case eH323_UU_PDU_h323_message_body_facility:
1087                 ret = process_facility(skb, ct, ctinfo, data, dataoff,
1088                                        &pdu->h323_message_body.facility);
1089                 break;
1090         case eH323_UU_PDU_h323_message_body_progress:
1091                 ret = process_progress(skb, ct, ctinfo, data, dataoff,
1092                                        &pdu->h323_message_body.progress);
1093                 break;
1094         default:
1095                 pr_debug("nf_ct_q931: Q.931 signal %d\n",
1096                          pdu->h323_message_body.choice);
1097                 break;
1098         }
1099
1100         if (ret < 0)
1101                 return -1;
1102
1103         if (pdu->options & eH323_UU_PDU_h245Control) {
1104                 for (i = 0; i < pdu->h245Control.count; i++) {
1105                         ret = process_h245(skb, ct, ctinfo, data, dataoff,
1106                                            &pdu->h245Control.item[i]);
1107                         if (ret < 0)
1108                                 return -1;
1109                 }
1110         }
1111
1112         return 0;
1113 }
1114
1115 /****************************************************************************/
1116 static int q931_help(struct sk_buff *skb, unsigned int protoff,
1117                      struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1118 {
1119         static Q931 q931;
1120         unsigned char *data = NULL;
1121         int datalen;
1122         int dataoff;
1123         int ret;
1124
1125         /* Until there's been traffic both ways, don't look in packets. */
1126         if (ctinfo != IP_CT_ESTABLISHED && ctinfo != IP_CT_ESTABLISHED_REPLY)
1127                 return NF_ACCEPT;
1128
1129         pr_debug("nf_ct_q931: skblen = %u\n", skb->len);
1130
1131         spin_lock_bh(&nf_h323_lock);
1132
1133         /* Process each TPKT */
1134         while (get_tpkt_data(skb, protoff, ct, ctinfo,
1135                              &data, &datalen, &dataoff)) {
1136                 pr_debug("nf_ct_q931: TPKT len=%d ", datalen);
1137                 nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1138
1139                 /* Decode Q.931 signal */
1140                 ret = DecodeQ931(data, datalen, &q931);
1141                 if (ret < 0) {
1142                         pr_debug("nf_ct_q931: decoding error: %s\n",
1143                                  ret == H323_ERROR_BOUND ?
1144                                  "out of bound" : "out of range");
1145                         /* We don't drop when decoding error */
1146                         break;
1147                 }
1148
1149                 /* Process Q.931 signal */
1150                 if (process_q931(skb, ct, ctinfo, &data, dataoff, &q931) < 0)
1151                         goto drop;
1152         }
1153
1154         spin_unlock_bh(&nf_h323_lock);
1155         return NF_ACCEPT;
1156
1157       drop:
1158         spin_unlock_bh(&nf_h323_lock);
1159         if (net_ratelimit())
1160                 pr_info("nf_ct_q931: packet dropped\n");
1161         return NF_DROP;
1162 }
1163
1164 /****************************************************************************/
1165 static const struct nf_conntrack_expect_policy q931_exp_policy = {
1166         /* T.120 and H.245 */
1167         .max_expected           = H323_RTP_CHANNEL_MAX * 4 + 4,
1168         .timeout                = 240,
1169 };
1170
1171 static struct nf_conntrack_helper nf_conntrack_helper_q931[] __read_mostly = {
1172         {
1173                 .name                   = "Q.931",
1174                 .me                     = THIS_MODULE,
1175                 .tuple.src.l3num        = AF_INET,
1176                 .tuple.src.u.tcp.port   = cpu_to_be16(Q931_PORT),
1177                 .tuple.dst.protonum     = IPPROTO_TCP,
1178                 .help                   = q931_help,
1179                 .expect_policy          = &q931_exp_policy,
1180         },
1181         {
1182                 .name                   = "Q.931",
1183                 .me                     = THIS_MODULE,
1184                 .tuple.src.l3num        = AF_INET6,
1185                 .tuple.src.u.tcp.port   = cpu_to_be16(Q931_PORT),
1186                 .tuple.dst.protonum     = IPPROTO_TCP,
1187                 .help                   = q931_help,
1188                 .expect_policy          = &q931_exp_policy,
1189         },
1190 };
1191
1192 /****************************************************************************/
1193 static unsigned char *get_udp_data(struct sk_buff *skb, unsigned int protoff,
1194                                    int *datalen)
1195 {
1196         const struct udphdr *uh;
1197         struct udphdr _uh;
1198         int dataoff;
1199
1200         uh = skb_header_pointer(skb, protoff, sizeof(_uh), &_uh);
1201         if (uh == NULL)
1202                 return NULL;
1203         dataoff = protoff + sizeof(_uh);
1204         if (dataoff >= skb->len)
1205                 return NULL;
1206         *datalen = skb->len - dataoff;
1207         return skb_header_pointer(skb, dataoff, *datalen, h323_buffer);
1208 }
1209
1210 /****************************************************************************/
1211 static struct nf_conntrack_expect *find_expect(struct nf_conn *ct,
1212                                                union nf_inet_addr *addr,
1213                                                __be16 port)
1214 {
1215         struct net *net = nf_ct_net(ct);
1216         struct nf_conntrack_expect *exp;
1217         struct nf_conntrack_tuple tuple;
1218
1219         memset(&tuple.src.u3, 0, sizeof(tuple.src.u3));
1220         tuple.src.u.tcp.port = 0;
1221         memcpy(&tuple.dst.u3, addr, sizeof(tuple.dst.u3));
1222         tuple.dst.u.tcp.port = port;
1223         tuple.dst.protonum = IPPROTO_TCP;
1224
1225         exp = __nf_ct_expect_find(net, nf_ct_zone(ct), &tuple);
1226         if (exp && exp->master == ct)
1227                 return exp;
1228         return NULL;
1229 }
1230
1231 /****************************************************************************/
1232 static int set_expect_timeout(struct nf_conntrack_expect *exp,
1233                               unsigned timeout)
1234 {
1235         if (!exp || !del_timer(&exp->timeout))
1236                 return 0;
1237
1238         exp->timeout.expires = jiffies + timeout * HZ;
1239         add_timer(&exp->timeout);
1240
1241         return 1;
1242 }
1243
1244 /****************************************************************************/
1245 static int expect_q931(struct sk_buff *skb, struct nf_conn *ct,
1246                        enum ip_conntrack_info ctinfo,
1247                        unsigned char **data,
1248                        TransportAddress *taddr, int count)
1249 {
1250         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1251         int dir = CTINFO2DIR(ctinfo);
1252         int ret = 0;
1253         int i;
1254         __be16 port;
1255         union nf_inet_addr addr;
1256         struct nf_conntrack_expect *exp;
1257         typeof(nat_q931_hook) nat_q931;
1258
1259         /* Look for the first related address */
1260         for (i = 0; i < count; i++) {
1261                 if (get_h225_addr(ct, *data, &taddr[i], &addr, &port) &&
1262                     memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3,
1263                            sizeof(addr)) == 0 && port != 0)
1264                         break;
1265         }
1266
1267         if (i >= count)         /* Not found */
1268                 return 0;
1269
1270         /* Create expect for Q.931 */
1271         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1272                 return -1;
1273         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1274                           gkrouted_only ? /* only accept calls from GK? */
1275                                 &ct->tuplehash[!dir].tuple.src.u3 : NULL,
1276                           &ct->tuplehash[!dir].tuple.dst.u3,
1277                           IPPROTO_TCP, NULL, &port);
1278         exp->helper = nf_conntrack_helper_q931;
1279         exp->flags = NF_CT_EXPECT_PERMANENT;    /* Accept multiple calls */
1280
1281         nat_q931 = rcu_dereference(nat_q931_hook);
1282         if (nat_q931 && ct->status & IPS_NAT_MASK) {    /* Need NAT */
1283                 ret = nat_q931(skb, ct, ctinfo, data, taddr, i, port, exp);
1284         } else {                /* Conntrack only */
1285                 if (nf_ct_expect_related(exp) == 0) {
1286                         pr_debug("nf_ct_ras: expect Q.931 ");
1287                         nf_ct_dump_tuple(&exp->tuple);
1288
1289                         /* Save port for looking up expect in processing RCF */
1290                         info->sig_port[dir] = port;
1291                 } else
1292                         ret = -1;
1293         }
1294
1295         nf_ct_expect_put(exp);
1296
1297         return ret;
1298 }
1299
1300 /****************************************************************************/
1301 static int process_grq(struct sk_buff *skb, struct nf_conn *ct,
1302                        enum ip_conntrack_info ctinfo,
1303                        unsigned char **data, GatekeeperRequest *grq)
1304 {
1305         typeof(set_ras_addr_hook) set_ras_addr;
1306
1307         pr_debug("nf_ct_ras: GRQ\n");
1308
1309         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1310         if (set_ras_addr && ct->status & IPS_NAT_MASK)  /* NATed */
1311                 return set_ras_addr(skb, ct, ctinfo, data,
1312                                     &grq->rasAddress, 1);
1313         return 0;
1314 }
1315
1316 /****************************************************************************/
1317 static int process_gcf(struct sk_buff *skb, struct nf_conn *ct,
1318                        enum ip_conntrack_info ctinfo,
1319                        unsigned char **data, GatekeeperConfirm *gcf)
1320 {
1321         int dir = CTINFO2DIR(ctinfo);
1322         int ret = 0;
1323         __be16 port;
1324         union nf_inet_addr addr;
1325         struct nf_conntrack_expect *exp;
1326
1327         pr_debug("nf_ct_ras: GCF\n");
1328
1329         if (!get_h225_addr(ct, *data, &gcf->rasAddress, &addr, &port))
1330                 return 0;
1331
1332         /* Registration port is the same as discovery port */
1333         if (!memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1334             port == ct->tuplehash[dir].tuple.src.u.udp.port)
1335                 return 0;
1336
1337         /* Avoid RAS expectation loops. A GCF is never expected. */
1338         if (test_bit(IPS_EXPECTED_BIT, &ct->status))
1339                 return 0;
1340
1341         /* Need new expect */
1342         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1343                 return -1;
1344         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1345                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1346                           IPPROTO_UDP, NULL, &port);
1347         exp->helper = nf_conntrack_helper_ras;
1348
1349         if (nf_ct_expect_related(exp) == 0) {
1350                 pr_debug("nf_ct_ras: expect RAS ");
1351                 nf_ct_dump_tuple(&exp->tuple);
1352         } else
1353                 ret = -1;
1354
1355         nf_ct_expect_put(exp);
1356
1357         return ret;
1358 }
1359
1360 /****************************************************************************/
1361 static int process_rrq(struct sk_buff *skb, struct nf_conn *ct,
1362                        enum ip_conntrack_info ctinfo,
1363                        unsigned char **data, RegistrationRequest *rrq)
1364 {
1365         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1366         int ret;
1367         typeof(set_ras_addr_hook) set_ras_addr;
1368
1369         pr_debug("nf_ct_ras: RRQ\n");
1370
1371         ret = expect_q931(skb, ct, ctinfo, data,
1372                           rrq->callSignalAddress.item,
1373                           rrq->callSignalAddress.count);
1374         if (ret < 0)
1375                 return -1;
1376
1377         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1378         if (set_ras_addr && ct->status & IPS_NAT_MASK) {
1379                 ret = set_ras_addr(skb, ct, ctinfo, data,
1380                                    rrq->rasAddress.item,
1381                                    rrq->rasAddress.count);
1382                 if (ret < 0)
1383                         return -1;
1384         }
1385
1386         if (rrq->options & eRegistrationRequest_timeToLive) {
1387                 pr_debug("nf_ct_ras: RRQ TTL = %u seconds\n", rrq->timeToLive);
1388                 info->timeout = rrq->timeToLive;
1389         } else
1390                 info->timeout = default_rrq_ttl;
1391
1392         return 0;
1393 }
1394
1395 /****************************************************************************/
1396 static int process_rcf(struct sk_buff *skb, struct nf_conn *ct,
1397                        enum ip_conntrack_info ctinfo,
1398                        unsigned char **data, RegistrationConfirm *rcf)
1399 {
1400         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1401         int dir = CTINFO2DIR(ctinfo);
1402         int ret;
1403         struct nf_conntrack_expect *exp;
1404         typeof(set_sig_addr_hook) set_sig_addr;
1405
1406         pr_debug("nf_ct_ras: RCF\n");
1407
1408         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1409         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1410                 ret = set_sig_addr(skb, ct, ctinfo, data,
1411                                         rcf->callSignalAddress.item,
1412                                         rcf->callSignalAddress.count);
1413                 if (ret < 0)
1414                         return -1;
1415         }
1416
1417         if (rcf->options & eRegistrationConfirm_timeToLive) {
1418                 pr_debug("nf_ct_ras: RCF TTL = %u seconds\n", rcf->timeToLive);
1419                 info->timeout = rcf->timeToLive;
1420         }
1421
1422         if (info->timeout > 0) {
1423                 pr_debug("nf_ct_ras: set RAS connection timeout to "
1424                          "%u seconds\n", info->timeout);
1425                 nf_ct_refresh(ct, skb, info->timeout * HZ);
1426
1427                 /* Set expect timeout */
1428                 spin_lock_bh(&nf_conntrack_lock);
1429                 exp = find_expect(ct, &ct->tuplehash[dir].tuple.dst.u3,
1430                                   info->sig_port[!dir]);
1431                 if (exp) {
1432                         pr_debug("nf_ct_ras: set Q.931 expect "
1433                                  "timeout to %u seconds for",
1434                                  info->timeout);
1435                         nf_ct_dump_tuple(&exp->tuple);
1436                         set_expect_timeout(exp, info->timeout);
1437                 }
1438                 spin_unlock_bh(&nf_conntrack_lock);
1439         }
1440
1441         return 0;
1442 }
1443
1444 /****************************************************************************/
1445 static int process_urq(struct sk_buff *skb, struct nf_conn *ct,
1446                        enum ip_conntrack_info ctinfo,
1447                        unsigned char **data, UnregistrationRequest *urq)
1448 {
1449         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1450         int dir = CTINFO2DIR(ctinfo);
1451         int ret;
1452         typeof(set_sig_addr_hook) set_sig_addr;
1453
1454         pr_debug("nf_ct_ras: URQ\n");
1455
1456         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1457         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1458                 ret = set_sig_addr(skb, ct, ctinfo, data,
1459                                    urq->callSignalAddress.item,
1460                                    urq->callSignalAddress.count);
1461                 if (ret < 0)
1462                         return -1;
1463         }
1464
1465         /* Clear old expect */
1466         nf_ct_remove_expectations(ct);
1467         info->sig_port[dir] = 0;
1468         info->sig_port[!dir] = 0;
1469
1470         /* Give it 30 seconds for UCF or URJ */
1471         nf_ct_refresh(ct, skb, 30 * HZ);
1472
1473         return 0;
1474 }
1475
1476 /****************************************************************************/
1477 static int process_arq(struct sk_buff *skb, struct nf_conn *ct,
1478                        enum ip_conntrack_info ctinfo,
1479                        unsigned char **data, AdmissionRequest *arq)
1480 {
1481         const struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1482         int dir = CTINFO2DIR(ctinfo);
1483         __be16 port;
1484         union nf_inet_addr addr;
1485         typeof(set_h225_addr_hook) set_h225_addr;
1486
1487         pr_debug("nf_ct_ras: ARQ\n");
1488
1489         set_h225_addr = rcu_dereference(set_h225_addr_hook);
1490         if ((arq->options & eAdmissionRequest_destCallSignalAddress) &&
1491             get_h225_addr(ct, *data, &arq->destCallSignalAddress,
1492                           &addr, &port) &&
1493             !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1494             port == info->sig_port[dir] &&
1495             set_h225_addr && ct->status & IPS_NAT_MASK) {
1496                 /* Answering ARQ */
1497                 return set_h225_addr(skb, data, 0,
1498                                      &arq->destCallSignalAddress,
1499                                      &ct->tuplehash[!dir].tuple.dst.u3,
1500                                      info->sig_port[!dir]);
1501         }
1502
1503         if ((arq->options & eAdmissionRequest_srcCallSignalAddress) &&
1504             get_h225_addr(ct, *data, &arq->srcCallSignalAddress,
1505                           &addr, &port) &&
1506             !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1507             set_h225_addr && ct->status & IPS_NAT_MASK) {
1508                 /* Calling ARQ */
1509                 return set_h225_addr(skb, data, 0,
1510                                      &arq->srcCallSignalAddress,
1511                                      &ct->tuplehash[!dir].tuple.dst.u3,
1512                                      port);
1513         }
1514
1515         return 0;
1516 }
1517
1518 /****************************************************************************/
1519 static int process_acf(struct sk_buff *skb, struct nf_conn *ct,
1520                        enum ip_conntrack_info ctinfo,
1521                        unsigned char **data, AdmissionConfirm *acf)
1522 {
1523         int dir = CTINFO2DIR(ctinfo);
1524         int ret = 0;
1525         __be16 port;
1526         union nf_inet_addr addr;
1527         struct nf_conntrack_expect *exp;
1528         typeof(set_sig_addr_hook) set_sig_addr;
1529
1530         pr_debug("nf_ct_ras: ACF\n");
1531
1532         if (!get_h225_addr(ct, *data, &acf->destCallSignalAddress,
1533                            &addr, &port))
1534                 return 0;
1535
1536         if (!memcmp(&addr, &ct->tuplehash[dir].tuple.dst.u3, sizeof(addr))) {
1537                 /* Answering ACF */
1538                 set_sig_addr = rcu_dereference(set_sig_addr_hook);
1539                 if (set_sig_addr && ct->status & IPS_NAT_MASK)
1540                         return set_sig_addr(skb, ct, ctinfo, data,
1541                                             &acf->destCallSignalAddress, 1);
1542                 return 0;
1543         }
1544
1545         /* Need new expect */
1546         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1547                 return -1;
1548         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1549                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1550                           IPPROTO_TCP, NULL, &port);
1551         exp->flags = NF_CT_EXPECT_PERMANENT;
1552         exp->helper = nf_conntrack_helper_q931;
1553
1554         if (nf_ct_expect_related(exp) == 0) {
1555                 pr_debug("nf_ct_ras: expect Q.931 ");
1556                 nf_ct_dump_tuple(&exp->tuple);
1557         } else
1558                 ret = -1;
1559
1560         nf_ct_expect_put(exp);
1561
1562         return ret;
1563 }
1564
1565 /****************************************************************************/
1566 static int process_lrq(struct sk_buff *skb, struct nf_conn *ct,
1567                        enum ip_conntrack_info ctinfo,
1568                        unsigned char **data, LocationRequest *lrq)
1569 {
1570         typeof(set_ras_addr_hook) set_ras_addr;
1571
1572         pr_debug("nf_ct_ras: LRQ\n");
1573
1574         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1575         if (set_ras_addr && ct->status & IPS_NAT_MASK)
1576                 return set_ras_addr(skb, ct, ctinfo, data,
1577                                     &lrq->replyAddress, 1);
1578         return 0;
1579 }
1580
1581 /****************************************************************************/
1582 static int process_lcf(struct sk_buff *skb, struct nf_conn *ct,
1583                        enum ip_conntrack_info ctinfo,
1584                        unsigned char **data, LocationConfirm *lcf)
1585 {
1586         int dir = CTINFO2DIR(ctinfo);
1587         int ret = 0;
1588         __be16 port;
1589         union nf_inet_addr addr;
1590         struct nf_conntrack_expect *exp;
1591
1592         pr_debug("nf_ct_ras: LCF\n");
1593
1594         if (!get_h225_addr(ct, *data, &lcf->callSignalAddress,
1595                            &addr, &port))
1596                 return 0;
1597
1598         /* Need new expect for call signal */
1599         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1600                 return -1;
1601         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1602                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1603                           IPPROTO_TCP, NULL, &port);
1604         exp->flags = NF_CT_EXPECT_PERMANENT;
1605         exp->helper = nf_conntrack_helper_q931;
1606
1607         if (nf_ct_expect_related(exp) == 0) {
1608                 pr_debug("nf_ct_ras: expect Q.931 ");
1609                 nf_ct_dump_tuple(&exp->tuple);
1610         } else
1611                 ret = -1;
1612
1613         nf_ct_expect_put(exp);
1614
1615         /* Ignore rasAddress */
1616
1617         return ret;
1618 }
1619
1620 /****************************************************************************/
1621 static int process_irr(struct sk_buff *skb, struct nf_conn *ct,
1622                        enum ip_conntrack_info ctinfo,
1623                        unsigned char **data, InfoRequestResponse *irr)
1624 {
1625         int ret;
1626         typeof(set_ras_addr_hook) set_ras_addr;
1627         typeof(set_sig_addr_hook) set_sig_addr;
1628
1629         pr_debug("nf_ct_ras: IRR\n");
1630
1631         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1632         if (set_ras_addr && ct->status & IPS_NAT_MASK) {
1633                 ret = set_ras_addr(skb, ct, ctinfo, data,
1634                                    &irr->rasAddress, 1);
1635                 if (ret < 0)
1636                         return -1;
1637         }
1638
1639         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1640         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1641                 ret = set_sig_addr(skb, ct, ctinfo, data,
1642                                         irr->callSignalAddress.item,
1643                                         irr->callSignalAddress.count);
1644                 if (ret < 0)
1645                         return -1;
1646         }
1647
1648         return 0;
1649 }
1650
1651 /****************************************************************************/
1652 static int process_ras(struct sk_buff *skb, struct nf_conn *ct,
1653                        enum ip_conntrack_info ctinfo,
1654                        unsigned char **data, RasMessage *ras)
1655 {
1656         switch (ras->choice) {
1657         case eRasMessage_gatekeeperRequest:
1658                 return process_grq(skb, ct, ctinfo, data,
1659                                    &ras->gatekeeperRequest);
1660         case eRasMessage_gatekeeperConfirm:
1661                 return process_gcf(skb, ct, ctinfo, data,
1662                                    &ras->gatekeeperConfirm);
1663         case eRasMessage_registrationRequest:
1664                 return process_rrq(skb, ct, ctinfo, data,
1665                                    &ras->registrationRequest);
1666         case eRasMessage_registrationConfirm:
1667                 return process_rcf(skb, ct, ctinfo, data,
1668                                    &ras->registrationConfirm);
1669         case eRasMessage_unregistrationRequest:
1670                 return process_urq(skb, ct, ctinfo, data,
1671                                    &ras->unregistrationRequest);
1672         case eRasMessage_admissionRequest:
1673                 return process_arq(skb, ct, ctinfo, data,
1674                                    &ras->admissionRequest);
1675         case eRasMessage_admissionConfirm:
1676                 return process_acf(skb, ct, ctinfo, data,
1677                                    &ras->admissionConfirm);
1678         case eRasMessage_locationRequest:
1679                 return process_lrq(skb, ct, ctinfo, data,
1680                                    &ras->locationRequest);
1681         case eRasMessage_locationConfirm:
1682                 return process_lcf(skb, ct, ctinfo, data,
1683                                    &ras->locationConfirm);
1684         case eRasMessage_infoRequestResponse:
1685                 return process_irr(skb, ct, ctinfo, data,
1686                                    &ras->infoRequestResponse);
1687         default:
1688                 pr_debug("nf_ct_ras: RAS message %d\n", ras->choice);
1689                 break;
1690         }
1691
1692         return 0;
1693 }
1694
1695 /****************************************************************************/
1696 static int ras_help(struct sk_buff *skb, unsigned int protoff,
1697                     struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1698 {
1699         static RasMessage ras;
1700         unsigned char *data;
1701         int datalen = 0;
1702         int ret;
1703
1704         pr_debug("nf_ct_ras: skblen = %u\n", skb->len);
1705
1706         spin_lock_bh(&nf_h323_lock);
1707
1708         /* Get UDP data */
1709         data = get_udp_data(skb, protoff, &datalen);
1710         if (data == NULL)
1711                 goto accept;
1712         pr_debug("nf_ct_ras: RAS message len=%d ", datalen);
1713         nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1714
1715         /* Decode RAS message */
1716         ret = DecodeRasMessage(data, datalen, &ras);
1717         if (ret < 0) {
1718                 pr_debug("nf_ct_ras: decoding error: %s\n",
1719                          ret == H323_ERROR_BOUND ?
1720                          "out of bound" : "out of range");
1721                 goto accept;
1722         }
1723
1724         /* Process RAS message */
1725         if (process_ras(skb, ct, ctinfo, &data, &ras) < 0)
1726                 goto drop;
1727
1728       accept:
1729         spin_unlock_bh(&nf_h323_lock);
1730         return NF_ACCEPT;
1731
1732       drop:
1733         spin_unlock_bh(&nf_h323_lock);
1734         if (net_ratelimit())
1735                 pr_info("nf_ct_ras: packet dropped\n");
1736         return NF_DROP;
1737 }
1738
1739 /****************************************************************************/
1740 static const struct nf_conntrack_expect_policy ras_exp_policy = {
1741         .max_expected           = 32,
1742         .timeout                = 240,
1743 };
1744
1745 static struct nf_conntrack_helper nf_conntrack_helper_ras[] __read_mostly = {
1746         {
1747                 .name                   = "RAS",
1748                 .me                     = THIS_MODULE,
1749                 .tuple.src.l3num        = AF_INET,
1750                 .tuple.src.u.udp.port   = cpu_to_be16(RAS_PORT),
1751                 .tuple.dst.protonum     = IPPROTO_UDP,
1752                 .help                   = ras_help,
1753                 .expect_policy          = &ras_exp_policy,
1754         },
1755         {
1756                 .name                   = "RAS",
1757                 .me                     = THIS_MODULE,
1758                 .tuple.src.l3num        = AF_INET6,
1759                 .tuple.src.u.udp.port   = cpu_to_be16(RAS_PORT),
1760                 .tuple.dst.protonum     = IPPROTO_UDP,
1761                 .help                   = ras_help,
1762                 .expect_policy          = &ras_exp_policy,
1763         },
1764 };
1765
1766 /****************************************************************************/
1767 static void __exit nf_conntrack_h323_fini(void)
1768 {
1769         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[1]);
1770         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1771         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1772         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1773         nf_conntrack_helper_unregister(&nf_conntrack_helper_h245);
1774         kfree(h323_buffer);
1775         pr_debug("nf_ct_h323: fini\n");
1776 }
1777
1778 /****************************************************************************/
1779 static int __init nf_conntrack_h323_init(void)
1780 {
1781         int ret;
1782
1783         h323_buffer = kmalloc(65536, GFP_KERNEL);
1784         if (!h323_buffer)
1785                 return -ENOMEM;
1786         ret = nf_conntrack_helper_register(&nf_conntrack_helper_h245);
1787         if (ret < 0)
1788                 goto err1;
1789         ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[0]);
1790         if (ret < 0)
1791                 goto err2;
1792         ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[1]);
1793         if (ret < 0)
1794                 goto err3;
1795         ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[0]);
1796         if (ret < 0)
1797                 goto err4;
1798         ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[1]);
1799         if (ret < 0)
1800                 goto err5;
1801         pr_debug("nf_ct_h323: init success\n");
1802         return 0;
1803
1804 err5:
1805         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1806 err4:
1807         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1808 err3:
1809         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1810 err2:
1811         nf_conntrack_helper_unregister(&nf_conntrack_helper_h245);
1812 err1:
1813         kfree(h323_buffer);
1814         return ret;
1815 }
1816
1817 /****************************************************************************/
1818 module_init(nf_conntrack_h323_init);
1819 module_exit(nf_conntrack_h323_fini);
1820
1821 EXPORT_SYMBOL_GPL(get_h225_addr);
1822 EXPORT_SYMBOL_GPL(set_h245_addr_hook);
1823 EXPORT_SYMBOL_GPL(set_h225_addr_hook);
1824 EXPORT_SYMBOL_GPL(set_sig_addr_hook);
1825 EXPORT_SYMBOL_GPL(set_ras_addr_hook);
1826 EXPORT_SYMBOL_GPL(nat_rtp_rtcp_hook);
1827 EXPORT_SYMBOL_GPL(nat_t120_hook);
1828 EXPORT_SYMBOL_GPL(nat_h245_hook);
1829 EXPORT_SYMBOL_GPL(nat_callforwarding_hook);
1830 EXPORT_SYMBOL_GPL(nat_q931_hook);
1831
1832 MODULE_AUTHOR("Jing Min Zhao <zhaojingmin@users.sourceforge.net>");
1833 MODULE_DESCRIPTION("H.323 connection tracking helper");
1834 MODULE_LICENSE("GPL");
1835 MODULE_ALIAS("ip_conntrack_h323");
1836 MODULE_ALIAS_NFCT_HELPER("h323");