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, unsigned int protoff,
  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, unsigned int protoff,
  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 int protoff, 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 int protoff, 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 int protoff,
  76                           unsigned char **data, int dataoff,
  77                           H245_TransportAddress *taddr,
  78                           __be16 port, __be16 rtp_port,
  79                           struct nf_conntrack_expect *rtp_exp,
  80                           struct nf_conntrack_expect *rtcp_exp) __read_mostly;
  81 int (*nat_t120_hook) (struct sk_buff *skb,
  82                       struct nf_conn *ct,
  83                       enum ip_conntrack_info ctinfo,
  84                       unsigned int protoff,
  85                       unsigned char **data, int dataoff,
  86                       H245_TransportAddress *taddr, __be16 port,
  87                       struct nf_conntrack_expect *exp) __read_mostly;
  88 int (*nat_h245_hook) (struct sk_buff *skb,
  89                       struct nf_conn *ct,
  90                       enum ip_conntrack_info ctinfo,
  91                       unsigned int protoff,
  92                       unsigned char **data, int dataoff,
  93                       TransportAddress *taddr, __be16 port,
  94                       struct nf_conntrack_expect *exp) __read_mostly;
  95 int (*nat_callforwarding_hook) (struct sk_buff *skb,
  96                                 struct nf_conn *ct,
  97                                 enum ip_conntrack_info ctinfo,
  98                                 unsigned int protoff,
  99                                 unsigned char **data, int dataoff,
 100                                 TransportAddress *taddr, __be16 port,
 101                                 struct nf_conntrack_expect *exp) __read_mostly;
 102 int (*nat_q931_hook) (struct sk_buff *skb,
 103                       struct nf_conn *ct,
 104                       enum ip_conntrack_info ctinfo,
 105                       unsigned int protoff,
 106                       unsigned char **data, TransportAddress *taddr, int idx,
 107                       __be16 port, struct nf_conntrack_expect *exp)
 108                       __read_mostly;
 109
 110 static DEFINE_SPINLOCK(nf_h323_lock);
 111 static char *h323_buffer;
 112
 113 static struct nf_conntrack_helper nf_conntrack_helper_h245;
 114 static struct nf_conntrack_helper nf_conntrack_helper_q931[];
 115 static struct nf_conntrack_helper nf_conntrack_helper_ras[];
 116
 117 /****************************************************************************/
 118 static int get_tpkt_data(struct sk_buff *skb, unsigned int protoff,
 119                          struct nf_conn *ct, enum ip_conntrack_info ctinfo,
 120                          unsigned char **data, int *datalen, int *dataoff)
 121 {
 122         struct nf_ct_h323_master *info = nfct_help_data(ct);
 123         int dir = CTINFO2DIR(ctinfo);
 124         const struct tcphdr *th;
 125         struct tcphdr _tcph;
 126         int tcpdatalen;
 127         int tcpdataoff;
 128         unsigned char *tpkt;
 129         int tpktlen;
 130         int tpktoff;
 131
 132         /* Get TCP header */
 133         th = skb_header_pointer(skb, protoff, sizeof(_tcph), &_tcph);
 134         if (th == NULL)
 135                 return 0;
 136
 137         /* Get TCP data offset */
 138         tcpdataoff = protoff + th->doff * 4;
 139
 140         /* Get TCP data length */
 141         tcpdatalen = skb->len - tcpdataoff;
 142         if (tcpdatalen <= 0)    /* No TCP data */
 143                 goto clear_out;
 144
 145         if (*data == NULL) {    /* first TPKT */
 146                 /* Get first TPKT pointer */
 147                 tpkt = skb_header_pointer(skb, tcpdataoff, tcpdatalen,
 148                                           h323_buffer);
 149                 BUG_ON(tpkt == NULL);
 150
 151                 /* Validate TPKT identifier */
 152                 if (tcpdatalen < 4 || tpkt[0] != 0x03 || tpkt[1] != 0) {
 153                         /* Netmeeting sends TPKT header and data separately */
 154                         if (info->tpkt_len[dir] > 0) {
 155                                 pr_debug("nf_ct_h323: previous packet "
 156                                          "indicated separate TPKT data of %hu "
 157                                          "bytes\n", info->tpkt_len[dir]);
 158                                 if (info->tpkt_len[dir] <= tcpdatalen) {
 159                                         /* Yes, there was a TPKT header
 160                                          * received */
 161                                         *data = tpkt;
 162                                         *datalen = info->tpkt_len[dir];
 163                                         *dataoff = 0;
 164                                         goto out;
 165                                 }
 166
 167                                 /* Fragmented TPKT */
 168                                 pr_debug("nf_ct_h323: fragmented TPKT\n");
 169                                 goto clear_out;
 170                         }
 171
 172                         /* It is not even a TPKT */
 173                         return 0;
 174                 }
 175                 tpktoff = 0;
 176         } else {                /* Next TPKT */
 177                 tpktoff = *dataoff + *datalen;
 178                 tcpdatalen -= tpktoff;
 179                 if (tcpdatalen <= 4)    /* No more TPKT */
 180                         goto clear_out;
 181                 tpkt = *data + *datalen;
 182
 183                 /* Validate TPKT identifier */
 184                 if (tpkt[0] != 0x03 || tpkt[1] != 0)
 185                         goto clear_out;
 186         }
 187
 188         /* Validate TPKT length */
 189         tpktlen = tpkt[2] * 256 + tpkt[3];
 190         if (tpktlen < 4)
 191                 goto clear_out;
 192         if (tpktlen > tcpdatalen) {
 193                 if (tcpdatalen == 4) {  /* Separate TPKT header */
 194                         /* Netmeeting sends TPKT header and data separately */
 195                         pr_debug("nf_ct_h323: separate TPKT header indicates "
 196                                  "there will be TPKT data of %hu bytes\n",
 197                                  tpktlen - 4);
 198                         info->tpkt_len[dir] = tpktlen - 4;
 199                         return 0;
 200                 }
 201
 202                 pr_debug("nf_ct_h323: incomplete TPKT (fragmented?)\n");
 203                 goto clear_out;
 204         }
 205
 206         /* This is the encapsulated data */
 207         *data = tpkt + 4;
 208         *datalen = tpktlen - 4;
 209         *dataoff = tpktoff + 4;
 210
 211       out:
 212         /* Clear TPKT length */
 213         info->tpkt_len[dir] = 0;
 214         return 1;
 215
 216       clear_out:
 217         info->tpkt_len[dir] = 0;
 218         return 0;
 219 }
 220
 221 /****************************************************************************/
 222 static int get_h245_addr(struct nf_conn *ct, const unsigned char *data,
 223                          H245_TransportAddress *taddr,
 224                          union nf_inet_addr *addr, __be16 *port)
 225 {
 226         const unsigned char *p;
 227         int len;
 228
 229         if (taddr->choice != eH245_TransportAddress_unicastAddress)
 230                 return 0;
 231
 232         switch (taddr->unicastAddress.choice) {
 233         case eUnicastAddress_iPAddress:
 234                 if (nf_ct_l3num(ct) != AF_INET)
 235                         return 0;
 236                 p = data + taddr->unicastAddress.iPAddress.network;
 237                 len = 4;
 238                 break;
 239         case eUnicastAddress_iP6Address:
 240                 if (nf_ct_l3num(ct) != AF_INET6)
 241                         return 0;
 242                 p = data + taddr->unicastAddress.iP6Address.network;
 243                 len = 16;
 244                 break;
 245         default:
 246                 return 0;
 247         }
 248
 249         memcpy(addr, p, len);
 250         memset((void *)addr + len, 0, sizeof(*addr) - len);
 251         memcpy(port, p + len, sizeof(__be16));
 252
 253         return 1;
 254 }
 255
 256 /****************************************************************************/
 257 static int expect_rtp_rtcp(struct sk_buff *skb, struct nf_conn *ct,
 258                            enum ip_conntrack_info ctinfo,
 259                            unsigned int protoff,
 260                            unsigned char **data, int dataoff,
 261                            H245_TransportAddress *taddr)
 262 {
 263         int dir = CTINFO2DIR(ctinfo);
 264         int ret = 0;
 265         __be16 port;
 266         __be16 rtp_port, rtcp_port;
 267         union nf_inet_addr addr;
 268         struct nf_conntrack_expect *rtp_exp;
 269         struct nf_conntrack_expect *rtcp_exp;
 270         typeof(nat_rtp_rtcp_hook) nat_rtp_rtcp;
 271
 272         /* Read RTP or RTCP address */
 273         if (!get_h245_addr(ct, *data, taddr, &addr, &port) ||
 274             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
 275             port == 0)
 276                 return 0;
 277
 278         /* RTP port is even */
 279         rtp_port = port & ~htons(1);
 280         rtcp_port = port | htons(1);
 281
 282         /* Create expect for RTP */
 283         if ((rtp_exp = nf_ct_expect_alloc(ct)) == NULL)
 284                 return -1;
 285         nf_ct_expect_init(rtp_exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 286                           &ct->tuplehash[!dir].tuple.src.u3,
 287                           &ct->tuplehash[!dir].tuple.dst.u3,
 288                           IPPROTO_UDP, NULL, &rtp_port);
 289
 290         /* Create expect for RTCP */
 291         if ((rtcp_exp = nf_ct_expect_alloc(ct)) == NULL) {
 292                 nf_ct_expect_put(rtp_exp);
 293                 return -1;
 294         }
 295         nf_ct_expect_init(rtcp_exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 296                           &ct->tuplehash[!dir].tuple.src.u3,
 297                           &ct->tuplehash[!dir].tuple.dst.u3,
 298                           IPPROTO_UDP, NULL, &rtcp_port);
 299
 300         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 301                    &ct->tuplehash[!dir].tuple.dst.u3,
 302                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 303                    (nat_rtp_rtcp = rcu_dereference(nat_rtp_rtcp_hook)) &&
 304                    nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 305                    ct->status & IPS_NAT_MASK) {
 306                 /* NAT needed */
 307                 ret = nat_rtp_rtcp(skb, ct, ctinfo, protoff, data, dataoff,
 308                                    taddr, port, rtp_port, rtp_exp, rtcp_exp);
 309         } else {                /* Conntrack only */
 310                 if (nf_ct_expect_related(rtp_exp) == 0) {
 311                         if (nf_ct_expect_related(rtcp_exp) == 0) {
 312                                 pr_debug("nf_ct_h323: expect RTP ");
 313                                 nf_ct_dump_tuple(&rtp_exp->tuple);
 314                                 pr_debug("nf_ct_h323: expect RTCP ");
 315                                 nf_ct_dump_tuple(&rtcp_exp->tuple);
 316                         } else {
 317                                 nf_ct_unexpect_related(rtp_exp);
 318                                 ret = -1;
 319                         }
 320                 } else
 321                         ret = -1;
 322         }
 323
 324         nf_ct_expect_put(rtp_exp);
 325         nf_ct_expect_put(rtcp_exp);
 326
 327         return ret;
 328 }
 329
 330 /****************************************************************************/
 331 static int expect_t120(struct sk_buff *skb,
 332                        struct nf_conn *ct,
 333                        enum ip_conntrack_info ctinfo,
 334                        unsigned int protoff,
 335                        unsigned char **data, int dataoff,
 336                        H245_TransportAddress *taddr)
 337 {
 338         int dir = CTINFO2DIR(ctinfo);
 339         int ret = 0;
 340         __be16 port;
 341         union nf_inet_addr addr;
 342         struct nf_conntrack_expect *exp;
 343         typeof(nat_t120_hook) nat_t120;
 344
 345         /* Read T.120 address */
 346         if (!get_h245_addr(ct, *data, taddr, &addr, &port) ||
 347             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
 348             port == 0)
 349                 return 0;
 350
 351         /* Create expect for T.120 connections */
 352         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
 353                 return -1;
 354         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 355                           &ct->tuplehash[!dir].tuple.src.u3,
 356                           &ct->tuplehash[!dir].tuple.dst.u3,
 357                           IPPROTO_TCP, NULL, &port);
 358         exp->flags = NF_CT_EXPECT_PERMANENT;    /* Accept multiple channels */
 359
 360         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 361                    &ct->tuplehash[!dir].tuple.dst.u3,
 362                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 363             (nat_t120 = rcu_dereference(nat_t120_hook)) &&
 364             nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 365             ct->status & IPS_NAT_MASK) {
 366                 /* NAT needed */
 367                 ret = nat_t120(skb, ct, ctinfo, protoff, data, dataoff, taddr,
 368                                port, exp);
 369         } else {                /* Conntrack only */
 370                 if (nf_ct_expect_related(exp) == 0) {
 371                         pr_debug("nf_ct_h323: expect T.120 ");
 372                         nf_ct_dump_tuple(&exp->tuple);
 373                 } else
 374                         ret = -1;
 375         }
 376
 377         nf_ct_expect_put(exp);
 378
 379         return ret;
 380 }
 381
 382 /****************************************************************************/
 383 static int process_h245_channel(struct sk_buff *skb,
 384                                 struct nf_conn *ct,
 385                                 enum ip_conntrack_info ctinfo,
 386                                 unsigned int protoff,
 387                                 unsigned char **data, int dataoff,
 388                                 H2250LogicalChannelParameters *channel)
 389 {
 390         int ret;
 391
 392         if (channel->options & eH2250LogicalChannelParameters_mediaChannel) {
 393                 /* RTP */
 394                 ret = expect_rtp_rtcp(skb, ct, ctinfo, protoff, data, dataoff,
 395                                       &channel->mediaChannel);
 396                 if (ret < 0)
 397                         return -1;
 398         }
 399
 400         if (channel->
 401             options & eH2250LogicalChannelParameters_mediaControlChannel) {
 402                 /* RTCP */
 403                 ret = expect_rtp_rtcp(skb, ct, ctinfo, protoff, data, dataoff,
 404                                       &channel->mediaControlChannel);
 405                 if (ret < 0)
 406                         return -1;
 407         }
 408
 409         return 0;
 410 }
 411
 412 /****************************************************************************/
 413 static int process_olc(struct sk_buff *skb, struct nf_conn *ct,
 414                        enum ip_conntrack_info ctinfo,
 415                        unsigned int protoff,
 416                        unsigned char **data, int dataoff,
 417                        OpenLogicalChannel *olc)
 418 {
 419         int ret;
 420
 421         pr_debug("nf_ct_h323: OpenLogicalChannel\n");
 422
 423         if (olc->forwardLogicalChannelParameters.multiplexParameters.choice ==
 424             eOpenLogicalChannel_forwardLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters)
 425         {
 426                 ret = process_h245_channel(skb, ct, ctinfo,
 427                                            protoff, data, dataoff,
 428                                            &olc->
 429                                            forwardLogicalChannelParameters.
 430                                            multiplexParameters.
 431                                            h2250LogicalChannelParameters);
 432                 if (ret < 0)
 433                         return -1;
 434         }
 435
 436         if ((olc->options &
 437              eOpenLogicalChannel_reverseLogicalChannelParameters) &&
 438             (olc->reverseLogicalChannelParameters.options &
 439              eOpenLogicalChannel_reverseLogicalChannelParameters_multiplexParameters)
 440             && (olc->reverseLogicalChannelParameters.multiplexParameters.
 441                 choice ==
 442                 eOpenLogicalChannel_reverseLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters))
 443         {
 444                 ret =
 445                     process_h245_channel(skb, ct, ctinfo,
 446                                          protoff, data, dataoff,
 447                                          &olc->
 448                                          reverseLogicalChannelParameters.
 449                                          multiplexParameters.
 450                                          h2250LogicalChannelParameters);
 451                 if (ret < 0)
 452                         return -1;
 453         }
 454
 455         if ((olc->options & eOpenLogicalChannel_separateStack) &&
 456             olc->forwardLogicalChannelParameters.dataType.choice ==
 457             eDataType_data &&
 458             olc->forwardLogicalChannelParameters.dataType.data.application.
 459             choice == eDataApplicationCapability_application_t120 &&
 460             olc->forwardLogicalChannelParameters.dataType.data.application.
 461             t120.choice == eDataProtocolCapability_separateLANStack &&
 462             olc->separateStack.networkAddress.choice ==
 463             eNetworkAccessParameters_networkAddress_localAreaAddress) {
 464                 ret = expect_t120(skb, ct, ctinfo, protoff, data, dataoff,
 465                                   &olc->separateStack.networkAddress.
 466                                   localAreaAddress);
 467                 if (ret < 0)
 468                         return -1;
 469         }
 470
 471         return 0;
 472 }
 473
 474 /****************************************************************************/
 475 static int process_olca(struct sk_buff *skb, struct nf_conn *ct,
 476                         enum ip_conntrack_info ctinfo,
 477                         unsigned int protoff, unsigned char **data, int dataoff,
 478                         OpenLogicalChannelAck *olca)
 479 {
 480         H2250LogicalChannelAckParameters *ack;
 481         int ret;
 482
 483         pr_debug("nf_ct_h323: OpenLogicalChannelAck\n");
 484
 485         if ((olca->options &
 486              eOpenLogicalChannelAck_reverseLogicalChannelParameters) &&
 487             (olca->reverseLogicalChannelParameters.options &
 488              eOpenLogicalChannelAck_reverseLogicalChannelParameters_multiplexParameters)
 489             && (olca->reverseLogicalChannelParameters.multiplexParameters.
 490                 choice ==
 491                 eOpenLogicalChannelAck_reverseLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters))
 492         {
 493                 ret = process_h245_channel(skb, ct, ctinfo,
 494                                            protoff, data, dataoff,
 495                                            &olca->
 496                                            reverseLogicalChannelParameters.
 497                                            multiplexParameters.
 498                                            h2250LogicalChannelParameters);
 499                 if (ret < 0)
 500                         return -1;
 501         }
 502
 503         if ((olca->options &
 504              eOpenLogicalChannelAck_forwardMultiplexAckParameters) &&
 505             (olca->forwardMultiplexAckParameters.choice ==
 506              eOpenLogicalChannelAck_forwardMultiplexAckParameters_h2250LogicalChannelAckParameters))
 507         {
 508                 ack = &olca->forwardMultiplexAckParameters.
 509                     h2250LogicalChannelAckParameters;
 510                 if (ack->options &
 511                     eH2250LogicalChannelAckParameters_mediaChannel) {
 512                         /* RTP */
 513                         ret = expect_rtp_rtcp(skb, ct, ctinfo,
 514                                               protoff, data, dataoff,
 515                                               &ack->mediaChannel);
 516                         if (ret < 0)
 517                                 return -1;
 518                 }
 519
 520                 if (ack->options &
 521                     eH2250LogicalChannelAckParameters_mediaControlChannel) {
 522                         /* RTCP */
 523                         ret = expect_rtp_rtcp(skb, ct, ctinfo,
 524                                               protoff, data, dataoff,
 525                                               &ack->mediaControlChannel);
 526                         if (ret < 0)
 527                                 return -1;
 528                 }
 529         }
 530
 531         if ((olca->options & eOpenLogicalChannelAck_separateStack) &&
 532                 olca->separateStack.networkAddress.choice ==
 533                 eNetworkAccessParameters_networkAddress_localAreaAddress) {
 534                 ret = expect_t120(skb, ct, ctinfo, protoff, data, dataoff,
 535                                   &olca->separateStack.networkAddress.
 536                                   localAreaAddress);
 537                 if (ret < 0)
 538                         return -1;
 539         }
 540
 541         return 0;
 542 }
 543
 544 /****************************************************************************/
 545 static int process_h245(struct sk_buff *skb, struct nf_conn *ct,
 546                         enum ip_conntrack_info ctinfo,
 547                         unsigned int protoff, unsigned char **data, int dataoff,
 548                         MultimediaSystemControlMessage *mscm)
 549 {
 550         switch (mscm->choice) {
 551         case eMultimediaSystemControlMessage_request:
 552                 if (mscm->request.choice ==
 553                     eRequestMessage_openLogicalChannel) {
 554                         return process_olc(skb, ct, ctinfo,
 555                                            protoff, data, dataoff,
 556                                            &mscm->request.openLogicalChannel);
 557                 }
 558                 pr_debug("nf_ct_h323: H.245 Request %d\n",
 559                          mscm->request.choice);
 560                 break;
 561         case eMultimediaSystemControlMessage_response:
 562                 if (mscm->response.choice ==
 563                     eResponseMessage_openLogicalChannelAck) {
 564                         return process_olca(skb, ct, ctinfo,
 565                                             protoff, data, dataoff,
 566                                             &mscm->response.
 567                                             openLogicalChannelAck);
 568                 }
 569                 pr_debug("nf_ct_h323: H.245 Response %d\n",
 570                          mscm->response.choice);
 571                 break;
 572         default:
 573                 pr_debug("nf_ct_h323: H.245 signal %d\n", mscm->choice);
 574                 break;
 575         }
 576
 577         return 0;
 578 }
 579
 580 /****************************************************************************/
 581 static int h245_help(struct sk_buff *skb, unsigned int protoff,
 582                      struct nf_conn *ct, enum ip_conntrack_info ctinfo)
 583 {
 584         static MultimediaSystemControlMessage mscm;
 585         unsigned char *data = NULL;
 586         int datalen;
 587         int dataoff;
 588         int ret;
 589
 590         /* Until there's been traffic both ways, don't look in packets. */
 591         if (ctinfo != IP_CT_ESTABLISHED && ctinfo != IP_CT_ESTABLISHED_REPLY)
 592                 return NF_ACCEPT;
 593
 594         pr_debug("nf_ct_h245: skblen = %u\n", skb->len);
 595
 596         spin_lock_bh(&nf_h323_lock);
 597
 598         /* Process each TPKT */
 599         while (get_tpkt_data(skb, protoff, ct, ctinfo,
 600                              &data, &datalen, &dataoff)) {
 601                 pr_debug("nf_ct_h245: TPKT len=%d ", datalen);
 602                 nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
 603
 604                 /* Decode H.245 signal */
 605                 ret = DecodeMultimediaSystemControlMessage(data, datalen,
 606                                                            &mscm);
 607                 if (ret < 0) {
 608                         pr_debug("nf_ct_h245: decoding error: %s\n",
 609                                  ret == H323_ERROR_BOUND ?
 610                                  "out of bound" : "out of range");
 611                         /* We don't drop when decoding error */
 612                         break;
 613                 }
 614
 615                 /* Process H.245 signal */
 616                 if (process_h245(skb, ct, ctinfo, protoff,
 617                                  &data, dataoff, &mscm) < 0)
 618                         goto drop;
 619         }
 620
 621         spin_unlock_bh(&nf_h323_lock);
 622         return NF_ACCEPT;
 623
 624       drop:
 625         spin_unlock_bh(&nf_h323_lock);
 626         net_info_ratelimited("nf_ct_h245: packet dropped\n");
 627         return NF_DROP;
 628 }
 629
 630 /****************************************************************************/
 631 static const struct nf_conntrack_expect_policy h245_exp_policy = {
 632         .max_expected   = H323_RTP_CHANNEL_MAX * 4 + 2 /* T.120 */,
 633         .timeout        = 240,
 634 };
 635
 636 static struct nf_conntrack_helper nf_conntrack_helper_h245 __read_mostly = {
 637         .name                   = "H.245",
 638         .me                     = THIS_MODULE,
 639         .data_len               = sizeof(struct nf_ct_h323_master),
 640         .tuple.src.l3num        = AF_UNSPEC,
 641         .tuple.dst.protonum     = IPPROTO_UDP,
 642         .help                   = h245_help,
 643         .expect_policy          = &h245_exp_policy,
 644 };
 645
 646 /****************************************************************************/
 647 int get_h225_addr(struct nf_conn *ct, unsigned char *data,
 648                   TransportAddress *taddr,
 649                   union nf_inet_addr *addr, __be16 *port)
 650 {
 651         const unsigned char *p;
 652         int len;
 653
 654         switch (taddr->choice) {
 655         case eTransportAddress_ipAddress:
 656                 if (nf_ct_l3num(ct) != AF_INET)
 657                         return 0;
 658                 p = data + taddr->ipAddress.ip;
 659                 len = 4;
 660                 break;
 661         case eTransportAddress_ip6Address:
 662                 if (nf_ct_l3num(ct) != AF_INET6)
 663                         return 0;
 664                 p = data + taddr->ip6Address.ip;
 665                 len = 16;
 666                 break;
 667         default:
 668                 return 0;
 669         }
 670
 671         memcpy(addr, p, len);
 672         memset((void *)addr + len, 0, sizeof(*addr) - len);
 673         memcpy(port, p + len, sizeof(__be16));
 674
 675         return 1;
 676 }
 677
 678 /****************************************************************************/
 679 static int expect_h245(struct sk_buff *skb, struct nf_conn *ct,
 680                        enum ip_conntrack_info ctinfo,
 681                        unsigned int protoff, unsigned char **data, int dataoff,
 682                        TransportAddress *taddr)
 683 {
 684         int dir = CTINFO2DIR(ctinfo);
 685         int ret = 0;
 686         __be16 port;
 687         union nf_inet_addr addr;
 688         struct nf_conntrack_expect *exp;
 689         typeof(nat_h245_hook) nat_h245;
 690
 691         /* Read h245Address */
 692         if (!get_h225_addr(ct, *data, taddr, &addr, &port) ||
 693             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
 694             port == 0)
 695                 return 0;
 696
 697         /* Create expect for h245 connection */
 698         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
 699                 return -1;
 700         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 701                           &ct->tuplehash[!dir].tuple.src.u3,
 702                           &ct->tuplehash[!dir].tuple.dst.u3,
 703                           IPPROTO_TCP, NULL, &port);
 704         exp->helper = &nf_conntrack_helper_h245;
 705
 706         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 707                    &ct->tuplehash[!dir].tuple.dst.u3,
 708                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 709             (nat_h245 = rcu_dereference(nat_h245_hook)) &&
 710             nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 711             ct->status & IPS_NAT_MASK) {
 712                 /* NAT needed */
 713                 ret = nat_h245(skb, ct, ctinfo, protoff, data, dataoff, taddr,
 714                                port, exp);
 715         } else {                /* Conntrack only */
 716                 if (nf_ct_expect_related(exp) == 0) {
 717                         pr_debug("nf_ct_q931: expect H.245 ");
 718                         nf_ct_dump_tuple(&exp->tuple);
 719                 } else
 720                         ret = -1;
 721         }
 722
 723         nf_ct_expect_put(exp);
 724
 725         return ret;
 726 }
 727
 728 /* If the calling party is on the same side of the forward-to party,
 729  * we don't need to track the second call */
 730 static int callforward_do_filter(const union nf_inet_addr *src,
 731                                  const union nf_inet_addr *dst,
 732                                  u_int8_t family)
 733 {
 734         const struct nf_afinfo *afinfo;
 735         int ret = 0;
 736
 737         /* rcu_read_lock()ed by nf_hook_slow() */
 738         afinfo = nf_get_afinfo(family);
 739         if (!afinfo)
 740                 return 0;
 741
 742         switch (family) {
 743         case AF_INET: {
 744                 struct flowi4 fl1, fl2;
 745                 struct rtable *rt1, *rt2;
 746
 747                 memset(&fl1, 0, sizeof(fl1));
 748                 fl1.daddr = src->ip;
 749
 750                 memset(&fl2, 0, sizeof(fl2));
 751                 fl2.daddr = dst->ip;
 752                 if (!afinfo->route(&init_net, (struct dst_entry **)&rt1,
 753                                    flowi4_to_flowi(&fl1), false)) {
 754                         if (!afinfo->route(&init_net, (struct dst_entry **)&rt2,
 755                                            flowi4_to_flowi(&fl2), false)) {
 756                                 if (rt_nexthop(rt1, fl1.daddr) ==
 757                                     rt_nexthop(rt2, fl2.daddr) &&
 758                                     rt1->dst.dev  == rt2->dst.dev)
 759                                         ret = 1;
 760                                 dst_release(&rt2->dst);
 761                         }
 762                         dst_release(&rt1->dst);
 763                 }
 764                 break;
 765         }
 766 #if IS_ENABLED(CONFIG_NF_CONNTRACK_IPV6)
 767         case AF_INET6: {
 768                 struct flowi6 fl1, fl2;
 769                 struct rt6_info *rt1, *rt2;
 770
 771                 memset(&fl1, 0, sizeof(fl1));
 772                 fl1.daddr = src->in6;
 773
 774                 memset(&fl2, 0, sizeof(fl2));
 775                 fl2.daddr = dst->in6;
 776                 if (!afinfo->route(&init_net, (struct dst_entry **)&rt1,
 777                                    flowi6_to_flowi(&fl1), false)) {
 778                         if (!afinfo->route(&init_net, (struct dst_entry **)&rt2,
 779                                            flowi6_to_flowi(&fl2), false)) {
 780                                 if (!memcmp(&rt1->rt6i_gateway, &rt2->rt6i_gateway,
 781                                             sizeof(rt1->rt6i_gateway)) &&
 782                                     rt1->dst.dev == rt2->dst.dev)
 783                                         ret = 1;
 784                                 dst_release(&rt2->dst);
 785                         }
 786                         dst_release(&rt1->dst);
 787                 }
 788                 break;
 789         }
 790 #endif
 791         }
 792         return ret;
 793
 794 }
 795
 796 /****************************************************************************/
 797 static int expect_callforwarding(struct sk_buff *skb,
 798                                  struct nf_conn *ct,
 799                                  enum ip_conntrack_info ctinfo,
 800                                  unsigned int protoff,
 801                                  unsigned char **data, int dataoff,
 802                                  TransportAddress *taddr)
 803 {
 804         int dir = CTINFO2DIR(ctinfo);
 805         int ret = 0;
 806         __be16 port;
 807         union nf_inet_addr addr;
 808         struct nf_conntrack_expect *exp;
 809         typeof(nat_callforwarding_hook) nat_callforwarding;
 810
 811         /* Read alternativeAddress */
 812         if (!get_h225_addr(ct, *data, taddr, &addr, &port) || port == 0)
 813                 return 0;
 814
 815         /* If the calling party is on the same side of the forward-to party,
 816          * we don't need to track the second call */
 817         if (callforward_filter &&
 818             callforward_do_filter(&addr, &ct->tuplehash[!dir].tuple.src.u3,
 819                                   nf_ct_l3num(ct))) {
 820                 pr_debug("nf_ct_q931: Call Forwarding not tracked\n");
 821                 return 0;
 822         }
 823
 824         /* Create expect for the second call leg */
 825         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
 826                 return -1;
 827         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 828                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
 829                           IPPROTO_TCP, NULL, &port);
 830         exp->helper = nf_conntrack_helper_q931;
 831
 832         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 833                    &ct->tuplehash[!dir].tuple.dst.u3,
 834                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 835             (nat_callforwarding = rcu_dereference(nat_callforwarding_hook)) &&
 836             nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 837             ct->status & IPS_NAT_MASK) {
 838                 /* Need NAT */
 839                 ret = nat_callforwarding(skb, ct, ctinfo,
 840                                          protoff, data, dataoff,
 841                                          taddr, port, exp);
 842         } else {                /* Conntrack only */
 843                 if (nf_ct_expect_related(exp) == 0) {
 844                         pr_debug("nf_ct_q931: expect Call Forwarding ");
 845                         nf_ct_dump_tuple(&exp->tuple);
 846                 } else
 847                         ret = -1;
 848         }
 849
 850         nf_ct_expect_put(exp);
 851
 852         return ret;
 853 }
 854
 855 /****************************************************************************/
 856 static int process_setup(struct sk_buff *skb, struct nf_conn *ct,
 857                          enum ip_conntrack_info ctinfo,
 858                          unsigned int protoff,
 859                          unsigned char **data, int dataoff,
 860                          Setup_UUIE *setup)
 861 {
 862         int dir = CTINFO2DIR(ctinfo);
 863         int ret;
 864         int i;
 865         __be16 port;
 866         union nf_inet_addr addr;
 867         typeof(set_h225_addr_hook) set_h225_addr;
 868
 869         pr_debug("nf_ct_q931: Setup\n");
 870
 871         if (setup->options & eSetup_UUIE_h245Address) {
 872                 ret = expect_h245(skb, ct, ctinfo, protoff, data, dataoff,
 873                                   &setup->h245Address);
 874                 if (ret < 0)
 875                         return -1;
 876         }
 877
 878         set_h225_addr = rcu_dereference(set_h225_addr_hook);
 879         if ((setup->options & eSetup_UUIE_destCallSignalAddress) &&
 880             (set_h225_addr) && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 881             ct->status & IPS_NAT_MASK &&
 882             get_h225_addr(ct, *data, &setup->destCallSignalAddress,
 883                           &addr, &port) &&
 884             memcmp(&addr, &ct->tuplehash[!dir].tuple.src.u3, sizeof(addr))) {
 885                 pr_debug("nf_ct_q931: set destCallSignalAddress %pI6:%hu->%pI6:%hu\n",
 886                          &addr, ntohs(port), &ct->tuplehash[!dir].tuple.src.u3,
 887                          ntohs(ct->tuplehash[!dir].tuple.src.u.tcp.port));
 888                 ret = set_h225_addr(skb, protoff, data, dataoff,
 889                                     &setup->destCallSignalAddress,
 890                                     &ct->tuplehash[!dir].tuple.src.u3,
 891                                     ct->tuplehash[!dir].tuple.src.u.tcp.port);
 892                 if (ret < 0)
 893                         return -1;
 894         }
 895
 896         if ((setup->options & eSetup_UUIE_sourceCallSignalAddress) &&
 897             (set_h225_addr) && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 898             ct->status & IPS_NAT_MASK &&
 899             get_h225_addr(ct, *data, &setup->sourceCallSignalAddress,
 900                           &addr, &port) &&
 901             memcmp(&addr, &ct->tuplehash[!dir].tuple.dst.u3, sizeof(addr))) {
 902                 pr_debug("nf_ct_q931: set sourceCallSignalAddress %pI6:%hu->%pI6:%hu\n",
 903                          &addr, ntohs(port), &ct->tuplehash[!dir].tuple.dst.u3,
 904                          ntohs(ct->tuplehash[!dir].tuple.dst.u.tcp.port));
 905                 ret = set_h225_addr(skb, protoff, data, dataoff,
 906                                     &setup->sourceCallSignalAddress,
 907                                     &ct->tuplehash[!dir].tuple.dst.u3,
 908                                     ct->tuplehash[!dir].tuple.dst.u.tcp.port);
 909                 if (ret < 0)
 910                         return -1;
 911         }
 912
 913         if (setup->options & eSetup_UUIE_fastStart) {
 914                 for (i = 0; i < setup->fastStart.count; i++) {
 915                         ret = process_olc(skb, ct, ctinfo,
 916                                           protoff, data, dataoff,
 917                                           &setup->fastStart.item[i]);
 918                         if (ret < 0)
 919                                 return -1;
 920                 }
 921         }
 922
 923         return 0;
 924 }
 925
 926 /****************************************************************************/
 927 static int process_callproceeding(struct sk_buff *skb,
 928                                   struct nf_conn *ct,
 929                                   enum ip_conntrack_info ctinfo,
 930                                   unsigned int protoff,
 931                                   unsigned char **data, int dataoff,
 932                                   CallProceeding_UUIE *callproc)
 933 {
 934         int ret;
 935         int i;
 936
 937         pr_debug("nf_ct_q931: CallProceeding\n");
 938
 939         if (callproc->options & eCallProceeding_UUIE_h245Address) {
 940                 ret = expect_h245(skb, ct, ctinfo, protoff, data, dataoff,
 941                                   &callproc->h245Address);
 942                 if (ret < 0)
 943                         return -1;
 944         }
 945
 946         if (callproc->options & eCallProceeding_UUIE_fastStart) {
 947                 for (i = 0; i < callproc->fastStart.count; i++) {
 948                         ret = process_olc(skb, ct, ctinfo,
 949                                           protoff, data, dataoff,
 950                                           &callproc->fastStart.item[i]);
 951                         if (ret < 0)
 952                                 return -1;
 953                 }
 954         }
 955
 956         return 0;
 957 }
 958
 959 /****************************************************************************/
 960 static int process_connect(struct sk_buff *skb, struct nf_conn *ct,
 961                            enum ip_conntrack_info ctinfo,
 962                            unsigned int protoff,
 963                            unsigned char **data, int dataoff,
 964                            Connect_UUIE *connect)
 965 {
 966         int ret;
 967         int i;
 968
 969         pr_debug("nf_ct_q931: Connect\n");
 970
 971         if (connect->options & eConnect_UUIE_h245Address) {
 972                 ret = expect_h245(skb, ct, ctinfo, protoff, data, dataoff,
 973                                   &connect->h245Address);
 974                 if (ret < 0)
 975                         return -1;
 976         }
 977
 978         if (connect->options & eConnect_UUIE_fastStart) {
 979                 for (i = 0; i < connect->fastStart.count; i++) {
 980                         ret = process_olc(skb, ct, ctinfo,
 981                                           protoff, data, dataoff,
 982                                           &connect->fastStart.item[i]);
 983                         if (ret < 0)
 984                                 return -1;
 985                 }
 986         }
 987
 988         return 0;
 989 }
 990
 991 /****************************************************************************/
 992 static int process_alerting(struct sk_buff *skb, struct nf_conn *ct,
 993                             enum ip_conntrack_info ctinfo,
 994                             unsigned int protoff,
 995                             unsigned char **data, int dataoff,
 996                             Alerting_UUIE *alert)
 997 {
 998         int ret;
 999         int i;
1000
1001         pr_debug("nf_ct_q931: Alerting\n");
1002
1003         if (alert->options & eAlerting_UUIE_h245Address) {
1004                 ret = expect_h245(skb, ct, ctinfo, protoff, data, dataoff,
1005                                   &alert->h245Address);
1006                 if (ret < 0)
1007                         return -1;
1008         }
1009
1010         if (alert->options & eAlerting_UUIE_fastStart) {
1011                 for (i = 0; i < alert->fastStart.count; i++) {
1012                         ret = process_olc(skb, ct, ctinfo,
1013                                           protoff, data, dataoff,
1014                                           &alert->fastStart.item[i]);
1015                         if (ret < 0)
1016                                 return -1;
1017                 }
1018         }
1019
1020         return 0;
1021 }
1022
1023 /****************************************************************************/
1024 static int process_facility(struct sk_buff *skb, struct nf_conn *ct,
1025                             enum ip_conntrack_info ctinfo,
1026                             unsigned int protoff,
1027                             unsigned char **data, int dataoff,
1028                             Facility_UUIE *facility)
1029 {
1030         int ret;
1031         int i;
1032
1033         pr_debug("nf_ct_q931: Facility\n");
1034
1035         if (facility->reason.choice == eFacilityReason_callForwarded) {
1036                 if (facility->options & eFacility_UUIE_alternativeAddress)
1037                         return expect_callforwarding(skb, ct, ctinfo,
1038                                                      protoff, data, dataoff,
1039                                                      &facility->
1040                                                      alternativeAddress);
1041                 return 0;
1042         }
1043
1044         if (facility->options & eFacility_UUIE_h245Address) {
1045                 ret = expect_h245(skb, ct, ctinfo, protoff, data, dataoff,
1046                                   &facility->h245Address);
1047                 if (ret < 0)
1048                         return -1;
1049         }
1050
1051         if (facility->options & eFacility_UUIE_fastStart) {
1052                 for (i = 0; i < facility->fastStart.count; i++) {
1053                         ret = process_olc(skb, ct, ctinfo,
1054                                           protoff, data, dataoff,
1055                                           &facility->fastStart.item[i]);
1056                         if (ret < 0)
1057                                 return -1;
1058                 }
1059         }
1060
1061         return 0;
1062 }
1063
1064 /****************************************************************************/
1065 static int process_progress(struct sk_buff *skb, struct nf_conn *ct,
1066                             enum ip_conntrack_info ctinfo,
1067                             unsigned int protoff,
1068                             unsigned char **data, int dataoff,
1069                             Progress_UUIE *progress)
1070 {
1071         int ret;
1072         int i;
1073
1074         pr_debug("nf_ct_q931: Progress\n");
1075
1076         if (progress->options & eProgress_UUIE_h245Address) {
1077                 ret = expect_h245(skb, ct, ctinfo, protoff, data, dataoff,
1078                                   &progress->h245Address);
1079                 if (ret < 0)
1080                         return -1;
1081         }
1082
1083         if (progress->options & eProgress_UUIE_fastStart) {
1084                 for (i = 0; i < progress->fastStart.count; i++) {
1085                         ret = process_olc(skb, ct, ctinfo,
1086                                           protoff, data, dataoff,
1087                                           &progress->fastStart.item[i]);
1088                         if (ret < 0)
1089                                 return -1;
1090                 }
1091         }
1092
1093         return 0;
1094 }
1095
1096 /****************************************************************************/
1097 static int process_q931(struct sk_buff *skb, struct nf_conn *ct,
1098                         enum ip_conntrack_info ctinfo,
1099                         unsigned int protoff, unsigned char **data, int dataoff,
1100                         Q931 *q931)
1101 {
1102         H323_UU_PDU *pdu = &q931->UUIE.h323_uu_pdu;
1103         int i;
1104         int ret = 0;
1105
1106         switch (pdu->h323_message_body.choice) {
1107         case eH323_UU_PDU_h323_message_body_setup:
1108                 ret = process_setup(skb, ct, ctinfo, protoff, data, dataoff,
1109                                     &pdu->h323_message_body.setup);
1110                 break;
1111         case eH323_UU_PDU_h323_message_body_callProceeding:
1112                 ret = process_callproceeding(skb, ct, ctinfo,
1113                                              protoff, data, dataoff,
1114                                              &pdu->h323_message_body.
1115                                              callProceeding);
1116                 break;
1117         case eH323_UU_PDU_h323_message_body_connect:
1118                 ret = process_connect(skb, ct, ctinfo, protoff, data, dataoff,
1119                                       &pdu->h323_message_body.connect);
1120                 break;
1121         case eH323_UU_PDU_h323_message_body_alerting:
1122                 ret = process_alerting(skb, ct, ctinfo, protoff, data, dataoff,
1123                                        &pdu->h323_message_body.alerting);
1124                 break;
1125         case eH323_UU_PDU_h323_message_body_facility:
1126                 ret = process_facility(skb, ct, ctinfo, protoff, data, dataoff,
1127                                        &pdu->h323_message_body.facility);
1128                 break;
1129         case eH323_UU_PDU_h323_message_body_progress:
1130                 ret = process_progress(skb, ct, ctinfo, protoff, data, dataoff,
1131                                        &pdu->h323_message_body.progress);
1132                 break;
1133         default:
1134                 pr_debug("nf_ct_q931: Q.931 signal %d\n",
1135                          pdu->h323_message_body.choice);
1136                 break;
1137         }
1138
1139         if (ret < 0)
1140                 return -1;
1141
1142         if (pdu->options & eH323_UU_PDU_h245Control) {
1143                 for (i = 0; i < pdu->h245Control.count; i++) {
1144                         ret = process_h245(skb, ct, ctinfo,
1145                                            protoff, data, dataoff,
1146                                            &pdu->h245Control.item[i]);
1147                         if (ret < 0)
1148                                 return -1;
1149                 }
1150         }
1151
1152         return 0;
1153 }
1154
1155 /****************************************************************************/
1156 static int q931_help(struct sk_buff *skb, unsigned int protoff,
1157                      struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1158 {
1159         static Q931 q931;
1160         unsigned char *data = NULL;
1161         int datalen;
1162         int dataoff;
1163         int ret;
1164
1165         /* Until there's been traffic both ways, don't look in packets. */
1166         if (ctinfo != IP_CT_ESTABLISHED && ctinfo != IP_CT_ESTABLISHED_REPLY)
1167                 return NF_ACCEPT;
1168
1169         pr_debug("nf_ct_q931: skblen = %u\n", skb->len);
1170
1171         spin_lock_bh(&nf_h323_lock);
1172
1173         /* Process each TPKT */
1174         while (get_tpkt_data(skb, protoff, ct, ctinfo,
1175                              &data, &datalen, &dataoff)) {
1176                 pr_debug("nf_ct_q931: TPKT len=%d ", datalen);
1177                 nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1178
1179                 /* Decode Q.931 signal */
1180                 ret = DecodeQ931(data, datalen, &q931);
1181                 if (ret < 0) {
1182                         pr_debug("nf_ct_q931: decoding error: %s\n",
1183                                  ret == H323_ERROR_BOUND ?
1184                                  "out of bound" : "out of range");
1185                         /* We don't drop when decoding error */
1186                         break;
1187                 }
1188
1189                 /* Process Q.931 signal */
1190                 if (process_q931(skb, ct, ctinfo, protoff,
1191                                  &data, dataoff, &q931) < 0)
1192                         goto drop;
1193         }
1194
1195         spin_unlock_bh(&nf_h323_lock);
1196         return NF_ACCEPT;
1197
1198       drop:
1199         spin_unlock_bh(&nf_h323_lock);
1200         net_info_ratelimited("nf_ct_q931: packet dropped\n");
1201         return NF_DROP;
1202 }
1203
1204 /****************************************************************************/
1205 static const struct nf_conntrack_expect_policy q931_exp_policy = {
1206         /* T.120 and H.245 */
1207         .max_expected           = H323_RTP_CHANNEL_MAX * 4 + 4,
1208         .timeout                = 240,
1209 };
1210
1211 static struct nf_conntrack_helper nf_conntrack_helper_q931[] __read_mostly = {
1212         {
1213                 .name                   = "Q.931",
1214                 .me                     = THIS_MODULE,
1215                 .data_len               = sizeof(struct nf_ct_h323_master),
1216                 .tuple.src.l3num        = AF_INET,
1217                 .tuple.src.u.tcp.port   = cpu_to_be16(Q931_PORT),
1218                 .tuple.dst.protonum     = IPPROTO_TCP,
1219                 .help                   = q931_help,
1220                 .expect_policy          = &q931_exp_policy,
1221         },
1222         {
1223                 .name                   = "Q.931",
1224                 .me                     = THIS_MODULE,
1225                 .tuple.src.l3num        = AF_INET6,
1226                 .tuple.src.u.tcp.port   = cpu_to_be16(Q931_PORT),
1227                 .tuple.dst.protonum     = IPPROTO_TCP,
1228                 .help                   = q931_help,
1229                 .expect_policy          = &q931_exp_policy,
1230         },
1231 };
1232
1233 /****************************************************************************/
1234 static unsigned char *get_udp_data(struct sk_buff *skb, unsigned int protoff,
1235                                    int *datalen)
1236 {
1237         const struct udphdr *uh;
1238         struct udphdr _uh;
1239         int dataoff;
1240
1241         uh = skb_header_pointer(skb, protoff, sizeof(_uh), &_uh);
1242         if (uh == NULL)
1243                 return NULL;
1244         dataoff = protoff + sizeof(_uh);
1245         if (dataoff >= skb->len)
1246                 return NULL;
1247         *datalen = skb->len - dataoff;
1248         return skb_header_pointer(skb, dataoff, *datalen, h323_buffer);
1249 }
1250
1251 /****************************************************************************/
1252 static struct nf_conntrack_expect *find_expect(struct nf_conn *ct,
1253                                                union nf_inet_addr *addr,
1254                                                __be16 port)
1255 {
1256         struct net *net = nf_ct_net(ct);
1257         struct nf_conntrack_expect *exp;
1258         struct nf_conntrack_tuple tuple;
1259
1260         memset(&tuple.src.u3, 0, sizeof(tuple.src.u3));
1261         tuple.src.u.tcp.port = 0;
1262         memcpy(&tuple.dst.u3, addr, sizeof(tuple.dst.u3));
1263         tuple.dst.u.tcp.port = port;
1264         tuple.dst.protonum = IPPROTO_TCP;
1265
1266         exp = __nf_ct_expect_find(net, nf_ct_zone(ct), &tuple);
1267         if (exp && exp->master == ct)
1268                 return exp;
1269         return NULL;
1270 }
1271
1272 /****************************************************************************/
1273 static int set_expect_timeout(struct nf_conntrack_expect *exp,
1274                               unsigned int timeout)
1275 {
1276         if (!exp || !del_timer(&exp->timeout))
1277                 return 0;
1278
1279         exp->timeout.expires = jiffies + timeout * HZ;
1280         add_timer(&exp->timeout);
1281
1282         return 1;
1283 }
1284
1285 /****************************************************************************/
1286 static int expect_q931(struct sk_buff *skb, struct nf_conn *ct,
1287                        enum ip_conntrack_info ctinfo,
1288                        unsigned int protoff, unsigned char **data,
1289                        TransportAddress *taddr, int count)
1290 {
1291         struct nf_ct_h323_master *info = nfct_help_data(ct);
1292         int dir = CTINFO2DIR(ctinfo);
1293         int ret = 0;
1294         int i;
1295         __be16 port;
1296         union nf_inet_addr addr;
1297         struct nf_conntrack_expect *exp;
1298         typeof(nat_q931_hook) nat_q931;
1299
1300         /* Look for the first related address */
1301         for (i = 0; i < count; i++) {
1302                 if (get_h225_addr(ct, *data, &taddr[i], &addr, &port) &&
1303                     memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3,
1304                            sizeof(addr)) == 0 && port != 0)
1305                         break;
1306         }
1307
1308         if (i >= count)         /* Not found */
1309                 return 0;
1310
1311         /* Create expect for Q.931 */
1312         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1313                 return -1;
1314         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1315                           gkrouted_only ? /* only accept calls from GK? */
1316                                 &ct->tuplehash[!dir].tuple.src.u3 : NULL,
1317                           &ct->tuplehash[!dir].tuple.dst.u3,
1318                           IPPROTO_TCP, NULL, &port);
1319         exp->helper = nf_conntrack_helper_q931;
1320         exp->flags = NF_CT_EXPECT_PERMANENT;    /* Accept multiple calls */
1321
1322         nat_q931 = rcu_dereference(nat_q931_hook);
1323         if (nat_q931 && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1324             ct->status & IPS_NAT_MASK) {        /* Need NAT */
1325                 ret = nat_q931(skb, ct, ctinfo, protoff, data,
1326                                taddr, i, port, exp);
1327         } else {                /* Conntrack only */
1328                 if (nf_ct_expect_related(exp) == 0) {
1329                         pr_debug("nf_ct_ras: expect Q.931 ");
1330                         nf_ct_dump_tuple(&exp->tuple);
1331
1332                         /* Save port for looking up expect in processing RCF */
1333                         info->sig_port[dir] = port;
1334                 } else
1335                         ret = -1;
1336         }
1337
1338         nf_ct_expect_put(exp);
1339
1340         return ret;
1341 }
1342
1343 /****************************************************************************/
1344 static int process_grq(struct sk_buff *skb, struct nf_conn *ct,
1345                        enum ip_conntrack_info ctinfo,
1346                        unsigned int protoff,
1347                        unsigned char **data, GatekeeperRequest *grq)
1348 {
1349         typeof(set_ras_addr_hook) set_ras_addr;
1350
1351         pr_debug("nf_ct_ras: GRQ\n");
1352
1353         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1354         if (set_ras_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1355             ct->status & IPS_NAT_MASK)  /* NATed */
1356                 return set_ras_addr(skb, ct, ctinfo, protoff, data,
1357                                     &grq->rasAddress, 1);
1358         return 0;
1359 }
1360
1361 /****************************************************************************/
1362 static int process_gcf(struct sk_buff *skb, struct nf_conn *ct,
1363                        enum ip_conntrack_info ctinfo,
1364                        unsigned int protoff,
1365                        unsigned char **data, GatekeeperConfirm *gcf)
1366 {
1367         int dir = CTINFO2DIR(ctinfo);
1368         int ret = 0;
1369         __be16 port;
1370         union nf_inet_addr addr;
1371         struct nf_conntrack_expect *exp;
1372
1373         pr_debug("nf_ct_ras: GCF\n");
1374
1375         if (!get_h225_addr(ct, *data, &gcf->rasAddress, &addr, &port))
1376                 return 0;
1377
1378         /* Registration port is the same as discovery port */
1379         if (!memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1380             port == ct->tuplehash[dir].tuple.src.u.udp.port)
1381                 return 0;
1382
1383         /* Avoid RAS expectation loops. A GCF is never expected. */
1384         if (test_bit(IPS_EXPECTED_BIT, &ct->status))
1385                 return 0;
1386
1387         /* Need new expect */
1388         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1389                 return -1;
1390         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1391                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1392                           IPPROTO_UDP, NULL, &port);
1393         exp->helper = nf_conntrack_helper_ras;
1394
1395         if (nf_ct_expect_related(exp) == 0) {
1396                 pr_debug("nf_ct_ras: expect RAS ");
1397                 nf_ct_dump_tuple(&exp->tuple);
1398         } else
1399                 ret = -1;
1400
1401         nf_ct_expect_put(exp);
1402
1403         return ret;
1404 }
1405
1406 /****************************************************************************/
1407 static int process_rrq(struct sk_buff *skb, struct nf_conn *ct,
1408                        enum ip_conntrack_info ctinfo,
1409                        unsigned int protoff,
1410                        unsigned char **data, RegistrationRequest *rrq)
1411 {
1412         struct nf_ct_h323_master *info = nfct_help_data(ct);
1413         int ret;
1414         typeof(set_ras_addr_hook) set_ras_addr;
1415
1416         pr_debug("nf_ct_ras: RRQ\n");
1417
1418         ret = expect_q931(skb, ct, ctinfo, protoff, data,
1419                           rrq->callSignalAddress.item,
1420                           rrq->callSignalAddress.count);
1421         if (ret < 0)
1422                 return -1;
1423
1424         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1425         if (set_ras_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1426             ct->status & IPS_NAT_MASK) {
1427                 ret = set_ras_addr(skb, ct, ctinfo, protoff, data,
1428                                    rrq->rasAddress.item,
1429                                    rrq->rasAddress.count);
1430                 if (ret < 0)
1431                         return -1;
1432         }
1433
1434         if (rrq->options & eRegistrationRequest_timeToLive) {
1435                 pr_debug("nf_ct_ras: RRQ TTL = %u seconds\n", rrq->timeToLive);
1436                 info->timeout = rrq->timeToLive;
1437         } else
1438                 info->timeout = default_rrq_ttl;
1439
1440         return 0;
1441 }
1442
1443 /****************************************************************************/
1444 static int process_rcf(struct sk_buff *skb, struct nf_conn *ct,
1445                        enum ip_conntrack_info ctinfo,
1446                        unsigned int protoff,
1447                        unsigned char **data, RegistrationConfirm *rcf)
1448 {
1449         struct nf_ct_h323_master *info = nfct_help_data(ct);
1450         int dir = CTINFO2DIR(ctinfo);
1451         int ret;
1452         struct nf_conntrack_expect *exp;
1453         typeof(set_sig_addr_hook) set_sig_addr;
1454
1455         pr_debug("nf_ct_ras: RCF\n");
1456
1457         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1458         if (set_sig_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1459             ct->status & IPS_NAT_MASK) {
1460                 ret = set_sig_addr(skb, ct, ctinfo, protoff, data,
1461                                         rcf->callSignalAddress.item,
1462                                         rcf->callSignalAddress.count);
1463                 if (ret < 0)
1464                         return -1;
1465         }
1466
1467         if (rcf->options & eRegistrationConfirm_timeToLive) {
1468                 pr_debug("nf_ct_ras: RCF TTL = %u seconds\n", rcf->timeToLive);
1469                 info->timeout = rcf->timeToLive;
1470         }
1471
1472         if (info->timeout > 0) {
1473                 pr_debug("nf_ct_ras: set RAS connection timeout to "
1474                          "%u seconds\n", info->timeout);
1475                 nf_ct_refresh(ct, skb, info->timeout * HZ);
1476
1477                 /* Set expect timeout */
1478                 spin_lock_bh(&nf_conntrack_lock);
1479                 exp = find_expect(ct, &ct->tuplehash[dir].tuple.dst.u3,
1480                                   info->sig_port[!dir]);
1481                 if (exp) {
1482                         pr_debug("nf_ct_ras: set Q.931 expect "
1483                                  "timeout to %u seconds for",
1484                                  info->timeout);
1485                         nf_ct_dump_tuple(&exp->tuple);
1486                         set_expect_timeout(exp, info->timeout);
1487                 }
1488                 spin_unlock_bh(&nf_conntrack_lock);
1489         }
1490
1491         return 0;
1492 }
1493
1494 /****************************************************************************/
1495 static int process_urq(struct sk_buff *skb, struct nf_conn *ct,
1496                        enum ip_conntrack_info ctinfo,
1497                        unsigned int protoff,
1498                        unsigned char **data, UnregistrationRequest *urq)
1499 {
1500         struct nf_ct_h323_master *info = nfct_help_data(ct);
1501         int dir = CTINFO2DIR(ctinfo);
1502         int ret;
1503         typeof(set_sig_addr_hook) set_sig_addr;
1504
1505         pr_debug("nf_ct_ras: URQ\n");
1506
1507         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1508         if (set_sig_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1509             ct->status & IPS_NAT_MASK) {
1510                 ret = set_sig_addr(skb, ct, ctinfo, protoff, data,
1511                                    urq->callSignalAddress.item,
1512                                    urq->callSignalAddress.count);
1513                 if (ret < 0)
1514                         return -1;
1515         }
1516
1517         /* Clear old expect */
1518         nf_ct_remove_expectations(ct);
1519         info->sig_port[dir] = 0;
1520         info->sig_port[!dir] = 0;
1521
1522         /* Give it 30 seconds for UCF or URJ */
1523         nf_ct_refresh(ct, skb, 30 * HZ);
1524
1525         return 0;
1526 }
1527
1528 /****************************************************************************/
1529 static int process_arq(struct sk_buff *skb, struct nf_conn *ct,
1530                        enum ip_conntrack_info ctinfo,
1531                        unsigned int protoff,
1532                        unsigned char **data, AdmissionRequest *arq)
1533 {
1534         const struct nf_ct_h323_master *info = nfct_help_data(ct);
1535         int dir = CTINFO2DIR(ctinfo);
1536         __be16 port;
1537         union nf_inet_addr addr;
1538         typeof(set_h225_addr_hook) set_h225_addr;
1539
1540         pr_debug("nf_ct_ras: ARQ\n");
1541
1542         set_h225_addr = rcu_dereference(set_h225_addr_hook);
1543         if ((arq->options & eAdmissionRequest_destCallSignalAddress) &&
1544             get_h225_addr(ct, *data, &arq->destCallSignalAddress,
1545                           &addr, &port) &&
1546             !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1547             port == info->sig_port[dir] &&
1548             nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1549             set_h225_addr && ct->status & IPS_NAT_MASK) {
1550                 /* Answering ARQ */
1551                 return set_h225_addr(skb, protoff, data, 0,
1552                                      &arq->destCallSignalAddress,
1553                                      &ct->tuplehash[!dir].tuple.dst.u3,
1554                                      info->sig_port[!dir]);
1555         }
1556
1557         if ((arq->options & eAdmissionRequest_srcCallSignalAddress) &&
1558             get_h225_addr(ct, *data, &arq->srcCallSignalAddress,
1559                           &addr, &port) &&
1560             !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1561             set_h225_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1562             ct->status & IPS_NAT_MASK) {
1563                 /* Calling ARQ */
1564                 return set_h225_addr(skb, protoff, data, 0,
1565                                      &arq->srcCallSignalAddress,
1566                                      &ct->tuplehash[!dir].tuple.dst.u3,
1567                                      port);
1568         }
1569
1570         return 0;
1571 }
1572
1573 /****************************************************************************/
1574 static int process_acf(struct sk_buff *skb, struct nf_conn *ct,
1575                        enum ip_conntrack_info ctinfo,
1576                        unsigned int protoff,
1577                        unsigned char **data, AdmissionConfirm *acf)
1578 {
1579         int dir = CTINFO2DIR(ctinfo);
1580         int ret = 0;
1581         __be16 port;
1582         union nf_inet_addr addr;
1583         struct nf_conntrack_expect *exp;
1584         typeof(set_sig_addr_hook) set_sig_addr;
1585
1586         pr_debug("nf_ct_ras: ACF\n");
1587
1588         if (!get_h225_addr(ct, *data, &acf->destCallSignalAddress,
1589                            &addr, &port))
1590                 return 0;
1591
1592         if (!memcmp(&addr, &ct->tuplehash[dir].tuple.dst.u3, sizeof(addr))) {
1593                 /* Answering ACF */
1594                 set_sig_addr = rcu_dereference(set_sig_addr_hook);
1595                 if (set_sig_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1596                     ct->status & IPS_NAT_MASK)
1597                         return set_sig_addr(skb, ct, ctinfo, protoff, data,
1598                                             &acf->destCallSignalAddress, 1);
1599                 return 0;
1600         }
1601
1602         /* Need new expect */
1603         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1604                 return -1;
1605         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1606                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1607                           IPPROTO_TCP, NULL, &port);
1608         exp->flags = NF_CT_EXPECT_PERMANENT;
1609         exp->helper = nf_conntrack_helper_q931;
1610
1611         if (nf_ct_expect_related(exp) == 0) {
1612                 pr_debug("nf_ct_ras: expect Q.931 ");
1613                 nf_ct_dump_tuple(&exp->tuple);
1614         } else
1615                 ret = -1;
1616
1617         nf_ct_expect_put(exp);
1618
1619         return ret;
1620 }
1621
1622 /****************************************************************************/
1623 static int process_lrq(struct sk_buff *skb, struct nf_conn *ct,
1624                        enum ip_conntrack_info ctinfo,
1625                        unsigned int protoff,
1626                        unsigned char **data, LocationRequest *lrq)
1627 {
1628         typeof(set_ras_addr_hook) set_ras_addr;
1629
1630         pr_debug("nf_ct_ras: LRQ\n");
1631
1632         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1633         if (set_ras_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1634             ct->status & IPS_NAT_MASK)
1635                 return set_ras_addr(skb, ct, ctinfo, protoff, data,
1636                                     &lrq->replyAddress, 1);
1637         return 0;
1638 }
1639
1640 /****************************************************************************/
1641 static int process_lcf(struct sk_buff *skb, struct nf_conn *ct,
1642                        enum ip_conntrack_info ctinfo,
1643                        unsigned int protoff,
1644                        unsigned char **data, LocationConfirm *lcf)
1645 {
1646         int dir = CTINFO2DIR(ctinfo);
1647         int ret = 0;
1648         __be16 port;
1649         union nf_inet_addr addr;
1650         struct nf_conntrack_expect *exp;
1651
1652         pr_debug("nf_ct_ras: LCF\n");
1653
1654         if (!get_h225_addr(ct, *data, &lcf->callSignalAddress,
1655                            &addr, &port))
1656                 return 0;
1657
1658         /* Need new expect for call signal */
1659         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1660                 return -1;
1661         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1662                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1663                           IPPROTO_TCP, NULL, &port);
1664         exp->flags = NF_CT_EXPECT_PERMANENT;
1665         exp->helper = nf_conntrack_helper_q931;
1666
1667         if (nf_ct_expect_related(exp) == 0) {
1668                 pr_debug("nf_ct_ras: expect Q.931 ");
1669                 nf_ct_dump_tuple(&exp->tuple);
1670         } else
1671                 ret = -1;
1672
1673         nf_ct_expect_put(exp);
1674
1675         /* Ignore rasAddress */
1676
1677         return ret;
1678 }
1679
1680 /****************************************************************************/
1681 static int process_irr(struct sk_buff *skb, struct nf_conn *ct,
1682                        enum ip_conntrack_info ctinfo,
1683                        unsigned int protoff,
1684                        unsigned char **data, InfoRequestResponse *irr)
1685 {
1686         int ret;
1687         typeof(set_ras_addr_hook) set_ras_addr;
1688         typeof(set_sig_addr_hook) set_sig_addr;
1689
1690         pr_debug("nf_ct_ras: IRR\n");
1691
1692         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1693         if (set_ras_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1694             ct->status & IPS_NAT_MASK) {
1695                 ret = set_ras_addr(skb, ct, ctinfo, protoff, data,
1696                                    &irr->rasAddress, 1);
1697                 if (ret < 0)
1698                         return -1;
1699         }
1700
1701         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1702         if (set_sig_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1703             ct->status & IPS_NAT_MASK) {
1704                 ret = set_sig_addr(skb, ct, ctinfo, protoff, data,
1705                                         irr->callSignalAddress.item,
1706                                         irr->callSignalAddress.count);
1707                 if (ret < 0)
1708                         return -1;
1709         }
1710
1711         return 0;
1712 }
1713
1714 /****************************************************************************/
1715 static int process_ras(struct sk_buff *skb, struct nf_conn *ct,
1716                        enum ip_conntrack_info ctinfo,
1717                        unsigned int protoff,
1718                        unsigned char **data, RasMessage *ras)
1719 {
1720         switch (ras->choice) {
1721         case eRasMessage_gatekeeperRequest:
1722                 return process_grq(skb, ct, ctinfo, protoff, data,
1723                                    &ras->gatekeeperRequest);
1724         case eRasMessage_gatekeeperConfirm:
1725                 return process_gcf(skb, ct, ctinfo, protoff, data,
1726                                    &ras->gatekeeperConfirm);
1727         case eRasMessage_registrationRequest:
1728                 return process_rrq(skb, ct, ctinfo, protoff, data,
1729                                    &ras->registrationRequest);
1730         case eRasMessage_registrationConfirm:
1731                 return process_rcf(skb, ct, ctinfo, protoff, data,
1732                                    &ras->registrationConfirm);
1733         case eRasMessage_unregistrationRequest:
1734                 return process_urq(skb, ct, ctinfo, protoff, data,
1735                                    &ras->unregistrationRequest);
1736         case eRasMessage_admissionRequest:
1737                 return process_arq(skb, ct, ctinfo, protoff, data,
1738                                    &ras->admissionRequest);
1739         case eRasMessage_admissionConfirm:
1740                 return process_acf(skb, ct, ctinfo, protoff, data,
1741                                    &ras->admissionConfirm);
1742         case eRasMessage_locationRequest:
1743                 return process_lrq(skb, ct, ctinfo, protoff, data,
1744                                    &ras->locationRequest);
1745         case eRasMessage_locationConfirm:
1746                 return process_lcf(skb, ct, ctinfo, protoff, data,
1747                                    &ras->locationConfirm);
1748         case eRasMessage_infoRequestResponse:
1749                 return process_irr(skb, ct, ctinfo, protoff, data,
1750                                    &ras->infoRequestResponse);
1751         default:
1752                 pr_debug("nf_ct_ras: RAS message %d\n", ras->choice);
1753                 break;
1754         }
1755
1756         return 0;
1757 }
1758
1759 /****************************************************************************/
1760 static int ras_help(struct sk_buff *skb, unsigned int protoff,
1761                     struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1762 {
1763         static RasMessage ras;
1764         unsigned char *data;
1765         int datalen = 0;
1766         int ret;
1767
1768         pr_debug("nf_ct_ras: skblen = %u\n", skb->len);
1769
1770         spin_lock_bh(&nf_h323_lock);
1771
1772         /* Get UDP data */
1773         data = get_udp_data(skb, protoff, &datalen);
1774         if (data == NULL)
1775                 goto accept;
1776         pr_debug("nf_ct_ras: RAS message len=%d ", datalen);
1777         nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1778
1779         /* Decode RAS message */
1780         ret = DecodeRasMessage(data, datalen, &ras);
1781         if (ret < 0) {
1782                 pr_debug("nf_ct_ras: decoding error: %s\n",
1783                          ret == H323_ERROR_BOUND ?
1784                          "out of bound" : "out of range");
1785                 goto accept;
1786         }
1787
1788         /* Process RAS message */
1789         if (process_ras(skb, ct, ctinfo, protoff, &data, &ras) < 0)
1790                 goto drop;
1791
1792       accept:
1793         spin_unlock_bh(&nf_h323_lock);
1794         return NF_ACCEPT;
1795
1796       drop:
1797         spin_unlock_bh(&nf_h323_lock);
1798         net_info_ratelimited("nf_ct_ras: packet dropped\n");
1799         return NF_DROP;
1800 }
1801
1802 /****************************************************************************/
1803 static const struct nf_conntrack_expect_policy ras_exp_policy = {
1804         .max_expected           = 32,
1805         .timeout                = 240,
1806 };
1807
1808 static struct nf_conntrack_helper nf_conntrack_helper_ras[] __read_mostly = {
1809         {
1810                 .name                   = "RAS",
1811                 .me                     = THIS_MODULE,
1812                 .data_len               = sizeof(struct nf_ct_h323_master),
1813                 .tuple.src.l3num        = AF_INET,
1814                 .tuple.src.u.udp.port   = cpu_to_be16(RAS_PORT),
1815                 .tuple.dst.protonum     = IPPROTO_UDP,
1816                 .help                   = ras_help,
1817                 .expect_policy          = &ras_exp_policy,
1818         },
1819         {
1820                 .name                   = "RAS",
1821                 .me                     = THIS_MODULE,
1822                 .data_len               = sizeof(struct nf_ct_h323_master),
1823                 .tuple.src.l3num        = AF_INET6,
1824                 .tuple.src.u.udp.port   = cpu_to_be16(RAS_PORT),
1825                 .tuple.dst.protonum     = IPPROTO_UDP,
1826                 .help                   = ras_help,
1827                 .expect_policy          = &ras_exp_policy,
1828         },
1829 };
1830
1831 /****************************************************************************/
1832 static void __exit nf_conntrack_h323_fini(void)
1833 {
1834         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[1]);
1835         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1836         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1837         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1838         nf_conntrack_helper_unregister(&nf_conntrack_helper_h245);
1839         kfree(h323_buffer);
1840         pr_debug("nf_ct_h323: fini\n");
1841 }
1842
1843 /****************************************************************************/
1844 static int __init nf_conntrack_h323_init(void)
1845 {
1846         int ret;
1847
1848         h323_buffer = kmalloc(65536, GFP_KERNEL);
1849         if (!h323_buffer)
1850                 return -ENOMEM;
1851         ret = nf_conntrack_helper_register(&nf_conntrack_helper_h245);
1852         if (ret < 0)
1853                 goto err1;
1854         ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[0]);
1855         if (ret < 0)
1856                 goto err2;
1857         ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[1]);
1858         if (ret < 0)
1859                 goto err3;
1860         ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[0]);
1861         if (ret < 0)
1862                 goto err4;
1863         ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[1]);
1864         if (ret < 0)
1865                 goto err5;
1866         pr_debug("nf_ct_h323: init success\n");
1867         return 0;
1868
1869 err5:
1870         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1871 err4:
1872         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1873 err3:
1874         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1875 err2:
1876         nf_conntrack_helper_unregister(&nf_conntrack_helper_h245);
1877 err1:
1878         kfree(h323_buffer);
1879         return ret;
1880 }
1881
1882 /****************************************************************************/
1883 module_init(nf_conntrack_h323_init);
1884 module_exit(nf_conntrack_h323_fini);
1885
1886 EXPORT_SYMBOL_GPL(get_h225_addr);
1887 EXPORT_SYMBOL_GPL(set_h245_addr_hook);
1888 EXPORT_SYMBOL_GPL(set_h225_addr_hook);
1889 EXPORT_SYMBOL_GPL(set_sig_addr_hook);
1890 EXPORT_SYMBOL_GPL(set_ras_addr_hook);
1891 EXPORT_SYMBOL_GPL(nat_rtp_rtcp_hook);
1892 EXPORT_SYMBOL_GPL(nat_t120_hook);
1893 EXPORT_SYMBOL_GPL(nat_h245_hook);
1894 EXPORT_SYMBOL_GPL(nat_callforwarding_hook);
1895 EXPORT_SYMBOL_GPL(nat_q931_hook);
1896
1897 MODULE_AUTHOR("Jing Min Zhao <zhaojingmin@users.sourceforge.net>");
1898 MODULE_DESCRIPTION("H.323 connection tracking helper");
1899 MODULE_LICENSE("GPL");
1900 MODULE_ALIAS("ip_conntrack_h323");
1901 MODULE_ALIAS_NFCT_HELPER("RAS");
1902 MODULE_ALIAS_NFCT_HELPER("Q.931");
1903 MODULE_ALIAS_NFCT_HELPER("H.245");