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