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 (rt1->rt_gateway == rt2->rt_gateway &&
 757                                     rt1->dst.dev  == rt2->dst.dev)
 758                                         ret = 1;
 759                                 dst_release(&rt2->dst);
 760                         }
 761                         dst_release(&rt1->dst);
 762                 }
 763                 break;
 764         }
 765 #if IS_ENABLED(CONFIG_NF_CONNTRACK_IPV6)
 766         case AF_INET6: {
 767                 struct flowi6 fl1, fl2;
 768                 struct rt6_info *rt1, *rt2;
 769
 770                 memset(&fl1, 0, sizeof(fl1));
 771                 fl1.daddr = src->in6;
 772
 773                 memset(&fl2, 0, sizeof(fl2));
 774                 fl2.daddr = dst->in6;
 775                 if (!afinfo->route(&init_net, (struct dst_entry **)&rt1,
 776                                    flowi6_to_flowi(&fl1), false)) {
 777                         if (!afinfo->route(&init_net, (struct dst_entry **)&rt2,
 778                                            flowi6_to_flowi(&fl2), false)) {
 779                                 if (!memcmp(&rt1->rt6i_gateway, &rt2->rt6i_gateway,
 780                                             sizeof(rt1->rt6i_gateway)) &&
 781                                     rt1->dst.dev == rt2->dst.dev)
 782                                         ret = 1;
 783                                 dst_release(&rt2->dst);
 784                         }
 785                         dst_release(&rt1->dst);
 786                 }
 787                 break;
 788         }
 789 #endif
 790         }
 791         return ret;
 792
 793 }
 794
 795 /****************************************************************************/
 796 static int expect_callforwarding(struct sk_buff *skb,
 797                                  struct nf_conn *ct,
 798                                  enum ip_conntrack_info ctinfo,
 799                                  unsigned int protoff,
 800                                  unsigned char **data, int dataoff,
 801                                  TransportAddress *taddr)
 802 {
 803         int dir = CTINFO2DIR(ctinfo);
 804         int ret = 0;
 805         __be16 port;
 806         union nf_inet_addr addr;
 807         struct nf_conntrack_expect *exp;
 808         typeof(nat_callforwarding_hook) nat_callforwarding;
 809
 810         /* Read alternativeAddress */
 811         if (!get_h225_addr(ct, *data, taddr, &addr, &port) || port == 0)
 812                 return 0;
 813
 814         /* If the calling party is on the same side of the forward-to party,
 815          * we don't need to track the second call */
 816         if (callforward_filter &&
 817             callforward_do_filter(&addr, &ct->tuplehash[!dir].tuple.src.u3,
 818                                   nf_ct_l3num(ct))) {
 819                 pr_debug("nf_ct_q931: Call Forwarding not tracked\n");
 820                 return 0;
 821         }
 822
 823         /* Create expect for the second call leg */
 824         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
 825                 return -1;
 826         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 827                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
 828                           IPPROTO_TCP, NULL, &port);
 829         exp->helper = nf_conntrack_helper_q931;
 830
 831         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 832                    &ct->tuplehash[!dir].tuple.dst.u3,
 833                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 834             (nat_callforwarding = rcu_dereference(nat_callforwarding_hook)) &&
 835             nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 836             ct->status & IPS_NAT_MASK) {
 837                 /* Need NAT */
 838                 ret = nat_callforwarding(skb, ct, ctinfo,
 839                                          protoff, data, dataoff,
 840                                          taddr, port, exp);
 841         } else {                /* Conntrack only */
 842                 if (nf_ct_expect_related(exp) == 0) {
 843                         pr_debug("nf_ct_q931: expect Call Forwarding ");
 844                         nf_ct_dump_tuple(&exp->tuple);
 845                 } else
 846                         ret = -1;
 847         }
 848
 849         nf_ct_expect_put(exp);
 850
 851         return ret;
 852 }
 853
 854 /****************************************************************************/
 855 static int process_setup(struct sk_buff *skb, struct nf_conn *ct,
 856                          enum ip_conntrack_info ctinfo,
 857                          unsigned int protoff,
 858                          unsigned char **data, int dataoff,
 859                          Setup_UUIE *setup)
 860 {
 861         int dir = CTINFO2DIR(ctinfo);
 862         int ret;
 863         int i;
 864         __be16 port;
 865         union nf_inet_addr addr;
 866         typeof(set_h225_addr_hook) set_h225_addr;
 867
 868         pr_debug("nf_ct_q931: Setup\n");
 869
 870         if (setup->options & eSetup_UUIE_h245Address) {
 871                 ret = expect_h245(skb, ct, ctinfo, protoff, data, dataoff,
 872                                   &setup->h245Address);
 873                 if (ret < 0)
 874                         return -1;
 875         }
 876
 877         set_h225_addr = rcu_dereference(set_h225_addr_hook);
 878         if ((setup->options & eSetup_UUIE_destCallSignalAddress) &&
 879             (set_h225_addr) && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 880             ct->status & IPS_NAT_MASK &&
 881             get_h225_addr(ct, *data, &setup->destCallSignalAddress,
 882                           &addr, &port) &&
 883             memcmp(&addr, &ct->tuplehash[!dir].tuple.src.u3, sizeof(addr))) {
 884                 pr_debug("nf_ct_q931: set destCallSignalAddress %pI6:%hu->%pI6:%hu\n",
 885                          &addr, ntohs(port), &ct->tuplehash[!dir].tuple.src.u3,
 886                          ntohs(ct->tuplehash[!dir].tuple.src.u.tcp.port));
 887                 ret = set_h225_addr(skb, protoff, data, dataoff,
 888                                     &setup->destCallSignalAddress,
 889                                     &ct->tuplehash[!dir].tuple.src.u3,
 890                                     ct->tuplehash[!dir].tuple.src.u.tcp.port);
 891                 if (ret < 0)
 892                         return -1;
 893         }
 894
 895         if ((setup->options & eSetup_UUIE_sourceCallSignalAddress) &&
 896             (set_h225_addr) && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 897             ct->status & IPS_NAT_MASK &&
 898             get_h225_addr(ct, *data, &setup->sourceCallSignalAddress,
 899                           &addr, &port) &&
 900             memcmp(&addr, &ct->tuplehash[!dir].tuple.dst.u3, sizeof(addr))) {
 901                 pr_debug("nf_ct_q931: set sourceCallSignalAddress %pI6:%hu->%pI6:%hu\n",
 902                          &addr, ntohs(port), &ct->tuplehash[!dir].tuple.dst.u3,
 903                          ntohs(ct->tuplehash[!dir].tuple.dst.u.tcp.port));
 904                 ret = set_h225_addr(skb, protoff, data, dataoff,
 905                                     &setup->sourceCallSignalAddress,
 906                                     &ct->tuplehash[!dir].tuple.dst.u3,
 907                                     ct->tuplehash[!dir].tuple.dst.u.tcp.port);
 908                 if (ret < 0)
 909                         return -1;
 910         }
 911
 912         if (setup->options & eSetup_UUIE_fastStart) {
 913                 for (i = 0; i < setup->fastStart.count; i++) {
 914                         ret = process_olc(skb, ct, ctinfo,
 915                                           protoff, data, dataoff,
 916                                           &setup->fastStart.item[i]);
 917                         if (ret < 0)
 918                                 return -1;
 919                 }
 920         }
 921
 922         return 0;
 923 }
 924
 925 /****************************************************************************/
 926 static int process_callproceeding(struct sk_buff *skb,
 927                                   struct nf_conn *ct,
 928                                   enum ip_conntrack_info ctinfo,
 929                                   unsigned int protoff,
 930                                   unsigned char **data, int dataoff,
 931                                   CallProceeding_UUIE *callproc)
 932 {
 933         int ret;
 934         int i;
 935
 936         pr_debug("nf_ct_q931: CallProceeding\n");
 937
 938         if (callproc->options & eCallProceeding_UUIE_h245Address) {
 939                 ret = expect_h245(skb, ct, ctinfo, protoff, data, dataoff,
 940                                   &callproc->h245Address);
 941                 if (ret < 0)
 942                         return -1;
 943         }
 944
 945         if (callproc->options & eCallProceeding_UUIE_fastStart) {
 946                 for (i = 0; i < callproc->fastStart.count; i++) {
 947                         ret = process_olc(skb, ct, ctinfo,
 948                                           protoff, data, dataoff,
 949                                           &callproc->fastStart.item[i]);
 950                         if (ret < 0)
 951                                 return -1;
 952                 }
 953         }
 954
 955         return 0;
 956 }
 957
 958 /****************************************************************************/
 959 static int process_connect(struct sk_buff *skb, struct nf_conn *ct,
 960                            enum ip_conntrack_info ctinfo,
 961                            unsigned int protoff,
 962                            unsigned char **data, int dataoff,
 963                            Connect_UUIE *connect)
 964 {
 965         int ret;
 966         int i;
 967
 968         pr_debug("nf_ct_q931: Connect\n");
 969
 970         if (connect->options & eConnect_UUIE_h245Address) {
 971                 ret = expect_h245(skb, ct, ctinfo, protoff, data, dataoff,
 972                                   &connect->h245Address);
 973                 if (ret < 0)
 974                         return -1;
 975         }
 976
 977         if (connect->options & eConnect_UUIE_fastStart) {
 978                 for (i = 0; i < connect->fastStart.count; i++) {
 979                         ret = process_olc(skb, ct, ctinfo,
 980                                           protoff, data, dataoff,
 981                                           &connect->fastStart.item[i]);
 982                         if (ret < 0)
 983                                 return -1;
 984                 }
 985         }
 986
 987         return 0;
 988 }
 989
 990 /****************************************************************************/
 991 static int process_alerting(struct sk_buff *skb, struct nf_conn *ct,
 992                             enum ip_conntrack_info ctinfo,
 993                             unsigned int protoff,
 994                             unsigned char **data, int dataoff,
 995                             Alerting_UUIE *alert)
 996 {
 997         int ret;
 998         int i;
 999
1000         pr_debug("nf_ct_q931: Alerting\n");
1001
1002         if (alert->options & eAlerting_UUIE_h245Address) {
1003                 ret = expect_h245(skb, ct, ctinfo, protoff, data, dataoff,
1004                                   &alert->h245Address);
1005                 if (ret < 0)
1006                         return -1;
1007         }
1008
1009         if (alert->options & eAlerting_UUIE_fastStart) {
1010                 for (i = 0; i < alert->fastStart.count; i++) {
1011                         ret = process_olc(skb, ct, ctinfo,
1012                                           protoff, data, dataoff,
1013                                           &alert->fastStart.item[i]);
1014                         if (ret < 0)
1015                                 return -1;
1016                 }
1017         }
1018
1019         return 0;
1020 }
1021
1022 /****************************************************************************/
1023 static int process_facility(struct sk_buff *skb, struct nf_conn *ct,
1024                             enum ip_conntrack_info ctinfo,
1025                             unsigned int protoff,
1026                             unsigned char **data, int dataoff,
1027                             Facility_UUIE *facility)
1028 {
1029         int ret;
1030         int i;
1031
1032         pr_debug("nf_ct_q931: Facility\n");
1033
1034         if (facility->reason.choice == eFacilityReason_callForwarded) {
1035                 if (facility->options & eFacility_UUIE_alternativeAddress)
1036                         return expect_callforwarding(skb, ct, ctinfo,
1037                                                      protoff, data, dataoff,
1038                                                      &facility->
1039                                                      alternativeAddress);
1040                 return 0;
1041         }
1042
1043         if (facility->options & eFacility_UUIE_h245Address) {
1044                 ret = expect_h245(skb, ct, ctinfo, protoff, data, dataoff,
1045                                   &facility->h245Address);
1046                 if (ret < 0)
1047                         return -1;
1048         }
1049
1050         if (facility->options & eFacility_UUIE_fastStart) {
1051                 for (i = 0; i < facility->fastStart.count; i++) {
1052                         ret = process_olc(skb, ct, ctinfo,
1053                                           protoff, data, dataoff,
1054                                           &facility->fastStart.item[i]);
1055                         if (ret < 0)
1056                                 return -1;
1057                 }
1058         }
1059
1060         return 0;
1061 }
1062
1063 /****************************************************************************/
1064 static int process_progress(struct sk_buff *skb, struct nf_conn *ct,
1065                             enum ip_conntrack_info ctinfo,
1066                             unsigned int protoff,
1067                             unsigned char **data, int dataoff,
1068                             Progress_UUIE *progress)
1069 {
1070         int ret;
1071         int i;
1072
1073         pr_debug("nf_ct_q931: Progress\n");
1074
1075         if (progress->options & eProgress_UUIE_h245Address) {
1076                 ret = expect_h245(skb, ct, ctinfo, protoff, data, dataoff,
1077                                   &progress->h245Address);
1078                 if (ret < 0)
1079                         return -1;
1080         }
1081
1082         if (progress->options & eProgress_UUIE_fastStart) {
1083                 for (i = 0; i < progress->fastStart.count; i++) {
1084                         ret = process_olc(skb, ct, ctinfo,
1085                                           protoff, data, dataoff,
1086                                           &progress->fastStart.item[i]);
1087                         if (ret < 0)
1088                                 return -1;
1089                 }
1090         }
1091
1092         return 0;
1093 }
1094
1095 /****************************************************************************/
1096 static int process_q931(struct sk_buff *skb, struct nf_conn *ct,
1097                         enum ip_conntrack_info ctinfo,
1098                         unsigned int protoff, unsigned char **data, int dataoff,
1099                         Q931 *q931)
1100 {
1101         H323_UU_PDU *pdu = &q931->UUIE.h323_uu_pdu;
1102         int i;
1103         int ret = 0;
1104
1105         switch (pdu->h323_message_body.choice) {
1106         case eH323_UU_PDU_h323_message_body_setup:
1107                 ret = process_setup(skb, ct, ctinfo, protoff, data, dataoff,
1108                                     &pdu->h323_message_body.setup);
1109                 break;
1110         case eH323_UU_PDU_h323_message_body_callProceeding:
1111                 ret = process_callproceeding(skb, ct, ctinfo,
1112                                              protoff, data, dataoff,
1113                                              &pdu->h323_message_body.
1114                                              callProceeding);
1115                 break;
1116         case eH323_UU_PDU_h323_message_body_connect:
1117                 ret = process_connect(skb, ct, ctinfo, protoff, data, dataoff,
1118                                       &pdu->h323_message_body.connect);
1119                 break;
1120         case eH323_UU_PDU_h323_message_body_alerting:
1121                 ret = process_alerting(skb, ct, ctinfo, protoff, data, dataoff,
1122                                        &pdu->h323_message_body.alerting);
1123                 break;
1124         case eH323_UU_PDU_h323_message_body_facility:
1125                 ret = process_facility(skb, ct, ctinfo, protoff, data, dataoff,
1126                                        &pdu->h323_message_body.facility);
1127                 break;
1128         case eH323_UU_PDU_h323_message_body_progress:
1129                 ret = process_progress(skb, ct, ctinfo, protoff, data, dataoff,
1130                                        &pdu->h323_message_body.progress);
1131                 break;
1132         default:
1133                 pr_debug("nf_ct_q931: Q.931 signal %d\n",
1134                          pdu->h323_message_body.choice);
1135                 break;
1136         }
1137
1138         if (ret < 0)
1139                 return -1;
1140
1141         if (pdu->options & eH323_UU_PDU_h245Control) {
1142                 for (i = 0; i < pdu->h245Control.count; i++) {
1143                         ret = process_h245(skb, ct, ctinfo,
1144                                            protoff, data, dataoff,
1145                                            &pdu->h245Control.item[i]);
1146                         if (ret < 0)
1147                                 return -1;
1148                 }
1149         }
1150
1151         return 0;
1152 }
1153
1154 /****************************************************************************/
1155 static int q931_help(struct sk_buff *skb, unsigned int protoff,
1156                      struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1157 {
1158         static Q931 q931;
1159         unsigned char *data = NULL;
1160         int datalen;
1161         int dataoff;
1162         int ret;
1163
1164         /* Until there's been traffic both ways, don't look in packets. */
1165         if (ctinfo != IP_CT_ESTABLISHED && ctinfo != IP_CT_ESTABLISHED_REPLY)
1166                 return NF_ACCEPT;
1167
1168         pr_debug("nf_ct_q931: skblen = %u\n", skb->len);
1169
1170         spin_lock_bh(&nf_h323_lock);
1171
1172         /* Process each TPKT */
1173         while (get_tpkt_data(skb, protoff, ct, ctinfo,
1174                              &data, &datalen, &dataoff)) {
1175                 pr_debug("nf_ct_q931: TPKT len=%d ", datalen);
1176                 nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1177
1178                 /* Decode Q.931 signal */
1179                 ret = DecodeQ931(data, datalen, &q931);
1180                 if (ret < 0) {
1181                         pr_debug("nf_ct_q931: decoding error: %s\n",
1182                                  ret == H323_ERROR_BOUND ?
1183                                  "out of bound" : "out of range");
1184                         /* We don't drop when decoding error */
1185                         break;
1186                 }
1187
1188                 /* Process Q.931 signal */
1189                 if (process_q931(skb, ct, ctinfo, protoff,
1190                                  &data, dataoff, &q931) < 0)
1191                         goto drop;
1192         }
1193
1194         spin_unlock_bh(&nf_h323_lock);
1195         return NF_ACCEPT;
1196
1197       drop:
1198         spin_unlock_bh(&nf_h323_lock);
1199         net_info_ratelimited("nf_ct_q931: packet dropped\n");
1200         return NF_DROP;
1201 }
1202
1203 /****************************************************************************/
1204 static const struct nf_conntrack_expect_policy q931_exp_policy = {
1205         /* T.120 and H.245 */
1206         .max_expected           = H323_RTP_CHANNEL_MAX * 4 + 4,
1207         .timeout                = 240,
1208 };
1209
1210 static struct nf_conntrack_helper nf_conntrack_helper_q931[] __read_mostly = {
1211         {
1212                 .name                   = "Q.931",
1213                 .me                     = THIS_MODULE,
1214                 .data_len               = sizeof(struct nf_ct_h323_master),
1215                 .tuple.src.l3num        = AF_INET,
1216                 .tuple.src.u.tcp.port   = cpu_to_be16(Q931_PORT),
1217                 .tuple.dst.protonum     = IPPROTO_TCP,
1218                 .help                   = q931_help,
1219                 .expect_policy          = &q931_exp_policy,
1220         },
1221         {
1222                 .name                   = "Q.931",
1223                 .me                     = THIS_MODULE,
1224                 .tuple.src.l3num        = AF_INET6,
1225                 .tuple.src.u.tcp.port   = cpu_to_be16(Q931_PORT),
1226                 .tuple.dst.protonum     = IPPROTO_TCP,
1227                 .help                   = q931_help,
1228                 .expect_policy          = &q931_exp_policy,
1229         },
1230 };
1231
1232 /****************************************************************************/
1233 static unsigned char *get_udp_data(struct sk_buff *skb, unsigned int protoff,
1234                                    int *datalen)
1235 {
1236         const struct udphdr *uh;
1237         struct udphdr _uh;
1238         int dataoff;
1239
1240         uh = skb_header_pointer(skb, protoff, sizeof(_uh), &_uh);
1241         if (uh == NULL)
1242                 return NULL;
1243         dataoff = protoff + sizeof(_uh);
1244         if (dataoff >= skb->len)
1245                 return NULL;
1246         *datalen = skb->len - dataoff;
1247         return skb_header_pointer(skb, dataoff, *datalen, h323_buffer);
1248 }
1249
1250 /****************************************************************************/
1251 static struct nf_conntrack_expect *find_expect(struct nf_conn *ct,
1252                                                union nf_inet_addr *addr,
1253                                                __be16 port)
1254 {
1255         struct net *net = nf_ct_net(ct);
1256         struct nf_conntrack_expect *exp;
1257         struct nf_conntrack_tuple tuple;
1258
1259         memset(&tuple.src.u3, 0, sizeof(tuple.src.u3));
1260         tuple.src.u.tcp.port = 0;
1261         memcpy(&tuple.dst.u3, addr, sizeof(tuple.dst.u3));
1262         tuple.dst.u.tcp.port = port;
1263         tuple.dst.protonum = IPPROTO_TCP;
1264
1265         exp = __nf_ct_expect_find(net, nf_ct_zone(ct), &tuple);
1266         if (exp && exp->master == ct)
1267                 return exp;
1268         return NULL;
1269 }
1270
1271 /****************************************************************************/
1272 static int set_expect_timeout(struct nf_conntrack_expect *exp,
1273                               unsigned int timeout)
1274 {
1275         if (!exp || !del_timer(&exp->timeout))
1276                 return 0;
1277
1278         exp->timeout.expires = jiffies + timeout * HZ;
1279         add_timer(&exp->timeout);
1280
1281         return 1;
1282 }
1283
1284 /****************************************************************************/
1285 static int expect_q931(struct sk_buff *skb, struct nf_conn *ct,
1286                        enum ip_conntrack_info ctinfo,
1287                        unsigned int protoff, unsigned char **data,
1288                        TransportAddress *taddr, int count)
1289 {
1290         struct nf_ct_h323_master *info = nfct_help_data(ct);
1291         int dir = CTINFO2DIR(ctinfo);
1292         int ret = 0;
1293         int i;
1294         __be16 port;
1295         union nf_inet_addr addr;
1296         struct nf_conntrack_expect *exp;
1297         typeof(nat_q931_hook) nat_q931;
1298
1299         /* Look for the first related address */
1300         for (i = 0; i < count; i++) {
1301                 if (get_h225_addr(ct, *data, &taddr[i], &addr, &port) &&
1302                     memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3,
1303                            sizeof(addr)) == 0 && port != 0)
1304                         break;
1305         }
1306
1307         if (i >= count)         /* Not found */
1308                 return 0;
1309
1310         /* Create expect for Q.931 */
1311         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1312                 return -1;
1313         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1314                           gkrouted_only ? /* only accept calls from GK? */
1315                                 &ct->tuplehash[!dir].tuple.src.u3 : NULL,
1316                           &ct->tuplehash[!dir].tuple.dst.u3,
1317                           IPPROTO_TCP, NULL, &port);
1318         exp->helper = nf_conntrack_helper_q931;
1319         exp->flags = NF_CT_EXPECT_PERMANENT;    /* Accept multiple calls */
1320
1321         nat_q931 = rcu_dereference(nat_q931_hook);
1322         if (nat_q931 && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1323             ct->status & IPS_NAT_MASK) {        /* Need NAT */
1324                 ret = nat_q931(skb, ct, ctinfo, protoff, data,
1325                                taddr, i, port, exp);
1326         } else {                /* Conntrack only */
1327                 if (nf_ct_expect_related(exp) == 0) {
1328                         pr_debug("nf_ct_ras: expect Q.931 ");
1329                         nf_ct_dump_tuple(&exp->tuple);
1330
1331                         /* Save port for looking up expect in processing RCF */
1332                         info->sig_port[dir] = port;
1333                 } else
1334                         ret = -1;
1335         }
1336
1337         nf_ct_expect_put(exp);
1338
1339         return ret;
1340 }
1341
1342 /****************************************************************************/
1343 static int process_grq(struct sk_buff *skb, struct nf_conn *ct,
1344                        enum ip_conntrack_info ctinfo,
1345                        unsigned int protoff,
1346                        unsigned char **data, GatekeeperRequest *grq)
1347 {
1348         typeof(set_ras_addr_hook) set_ras_addr;
1349
1350         pr_debug("nf_ct_ras: GRQ\n");
1351
1352         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1353         if (set_ras_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1354             ct->status & IPS_NAT_MASK)  /* NATed */
1355                 return set_ras_addr(skb, ct, ctinfo, protoff, data,
1356                                     &grq->rasAddress, 1);
1357         return 0;
1358 }
1359
1360 /****************************************************************************/
1361 static int process_gcf(struct sk_buff *skb, struct nf_conn *ct,
1362                        enum ip_conntrack_info ctinfo,
1363                        unsigned int protoff,
1364                        unsigned char **data, GatekeeperConfirm *gcf)
1365 {
1366         int dir = CTINFO2DIR(ctinfo);
1367         int ret = 0;
1368         __be16 port;
1369         union nf_inet_addr addr;
1370         struct nf_conntrack_expect *exp;
1371
1372         pr_debug("nf_ct_ras: GCF\n");
1373
1374         if (!get_h225_addr(ct, *data, &gcf->rasAddress, &addr, &port))
1375                 return 0;
1376
1377         /* Registration port is the same as discovery port */
1378         if (!memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1379             port == ct->tuplehash[dir].tuple.src.u.udp.port)
1380                 return 0;
1381
1382         /* Avoid RAS expectation loops. A GCF is never expected. */
1383         if (test_bit(IPS_EXPECTED_BIT, &ct->status))
1384                 return 0;
1385
1386         /* Need new expect */
1387         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1388                 return -1;
1389         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1390                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1391                           IPPROTO_UDP, NULL, &port);
1392         exp->helper = nf_conntrack_helper_ras;
1393
1394         if (nf_ct_expect_related(exp) == 0) {
1395                 pr_debug("nf_ct_ras: expect RAS ");
1396                 nf_ct_dump_tuple(&exp->tuple);
1397         } else
1398                 ret = -1;
1399
1400         nf_ct_expect_put(exp);
1401
1402         return ret;
1403 }
1404
1405 /****************************************************************************/
1406 static int process_rrq(struct sk_buff *skb, struct nf_conn *ct,
1407                        enum ip_conntrack_info ctinfo,
1408                        unsigned int protoff,
1409                        unsigned char **data, RegistrationRequest *rrq)
1410 {
1411         struct nf_ct_h323_master *info = nfct_help_data(ct);
1412         int ret;
1413         typeof(set_ras_addr_hook) set_ras_addr;
1414
1415         pr_debug("nf_ct_ras: RRQ\n");
1416
1417         ret = expect_q931(skb, ct, ctinfo, protoff, data,
1418                           rrq->callSignalAddress.item,
1419                           rrq->callSignalAddress.count);
1420         if (ret < 0)
1421                 return -1;
1422
1423         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1424         if (set_ras_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1425             ct->status & IPS_NAT_MASK) {
1426                 ret = set_ras_addr(skb, ct, ctinfo, protoff, data,
1427                                    rrq->rasAddress.item,
1428                                    rrq->rasAddress.count);
1429                 if (ret < 0)
1430                         return -1;
1431         }
1432
1433         if (rrq->options & eRegistrationRequest_timeToLive) {
1434                 pr_debug("nf_ct_ras: RRQ TTL = %u seconds\n", rrq->timeToLive);
1435                 info->timeout = rrq->timeToLive;
1436         } else
1437                 info->timeout = default_rrq_ttl;
1438
1439         return 0;
1440 }
1441
1442 /****************************************************************************/
1443 static int process_rcf(struct sk_buff *skb, struct nf_conn *ct,
1444                        enum ip_conntrack_info ctinfo,
1445                        unsigned int protoff,
1446                        unsigned char **data, RegistrationConfirm *rcf)
1447 {
1448         struct nf_ct_h323_master *info = nfct_help_data(ct);
1449         int dir = CTINFO2DIR(ctinfo);
1450         int ret;
1451         struct nf_conntrack_expect *exp;
1452         typeof(set_sig_addr_hook) set_sig_addr;
1453
1454         pr_debug("nf_ct_ras: RCF\n");
1455
1456         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1457         if (set_sig_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1458             ct->status & IPS_NAT_MASK) {
1459                 ret = set_sig_addr(skb, ct, ctinfo, protoff, data,
1460                                         rcf->callSignalAddress.item,
1461                                         rcf->callSignalAddress.count);
1462                 if (ret < 0)
1463                         return -1;
1464         }
1465
1466         if (rcf->options & eRegistrationConfirm_timeToLive) {
1467                 pr_debug("nf_ct_ras: RCF TTL = %u seconds\n", rcf->timeToLive);
1468                 info->timeout = rcf->timeToLive;
1469         }
1470
1471         if (info->timeout > 0) {
1472                 pr_debug("nf_ct_ras: set RAS connection timeout to "
1473                          "%u seconds\n", info->timeout);
1474                 nf_ct_refresh(ct, skb, info->timeout * HZ);
1475
1476                 /* Set expect timeout */
1477                 spin_lock_bh(&nf_conntrack_lock);
1478                 exp = find_expect(ct, &ct->tuplehash[dir].tuple.dst.u3,
1479                                   info->sig_port[!dir]);
1480                 if (exp) {
1481                         pr_debug("nf_ct_ras: set Q.931 expect "
1482                                  "timeout to %u seconds for",
1483                                  info->timeout);
1484                         nf_ct_dump_tuple(&exp->tuple);
1485                         set_expect_timeout(exp, info->timeout);
1486                 }
1487                 spin_unlock_bh(&nf_conntrack_lock);
1488         }
1489
1490         return 0;
1491 }
1492
1493 /****************************************************************************/
1494 static int process_urq(struct sk_buff *skb, struct nf_conn *ct,
1495                        enum ip_conntrack_info ctinfo,
1496                        unsigned int protoff,
1497                        unsigned char **data, UnregistrationRequest *urq)
1498 {
1499         struct nf_ct_h323_master *info = nfct_help_data(ct);
1500         int dir = CTINFO2DIR(ctinfo);
1501         int ret;
1502         typeof(set_sig_addr_hook) set_sig_addr;
1503
1504         pr_debug("nf_ct_ras: URQ\n");
1505
1506         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1507         if (set_sig_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1508             ct->status & IPS_NAT_MASK) {
1509                 ret = set_sig_addr(skb, ct, ctinfo, protoff, data,
1510                                    urq->callSignalAddress.item,
1511                                    urq->callSignalAddress.count);
1512                 if (ret < 0)
1513                         return -1;
1514         }
1515
1516         /* Clear old expect */
1517         nf_ct_remove_expectations(ct);
1518         info->sig_port[dir] = 0;
1519         info->sig_port[!dir] = 0;
1520
1521         /* Give it 30 seconds for UCF or URJ */
1522         nf_ct_refresh(ct, skb, 30 * HZ);
1523
1524         return 0;
1525 }
1526
1527 /****************************************************************************/
1528 static int process_arq(struct sk_buff *skb, struct nf_conn *ct,
1529                        enum ip_conntrack_info ctinfo,
1530                        unsigned int protoff,
1531                        unsigned char **data, AdmissionRequest *arq)
1532 {
1533         const struct nf_ct_h323_master *info = nfct_help_data(ct);
1534         int dir = CTINFO2DIR(ctinfo);
1535         __be16 port;
1536         union nf_inet_addr addr;
1537         typeof(set_h225_addr_hook) set_h225_addr;
1538
1539         pr_debug("nf_ct_ras: ARQ\n");
1540
1541         set_h225_addr = rcu_dereference(set_h225_addr_hook);
1542         if ((arq->options & eAdmissionRequest_destCallSignalAddress) &&
1543             get_h225_addr(ct, *data, &arq->destCallSignalAddress,
1544                           &addr, &port) &&
1545             !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1546             port == info->sig_port[dir] &&
1547             nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1548             set_h225_addr && ct->status & IPS_NAT_MASK) {
1549                 /* Answering ARQ */
1550                 return set_h225_addr(skb, protoff, data, 0,
1551                                      &arq->destCallSignalAddress,
1552                                      &ct->tuplehash[!dir].tuple.dst.u3,
1553                                      info->sig_port[!dir]);
1554         }
1555
1556         if ((arq->options & eAdmissionRequest_srcCallSignalAddress) &&
1557             get_h225_addr(ct, *data, &arq->srcCallSignalAddress,
1558                           &addr, &port) &&
1559             !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1560             set_h225_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1561             ct->status & IPS_NAT_MASK) {
1562                 /* Calling ARQ */
1563                 return set_h225_addr(skb, protoff, data, 0,
1564                                      &arq->srcCallSignalAddress,
1565                                      &ct->tuplehash[!dir].tuple.dst.u3,
1566                                      port);
1567         }
1568
1569         return 0;
1570 }
1571
1572 /****************************************************************************/
1573 static int process_acf(struct sk_buff *skb, struct nf_conn *ct,
1574                        enum ip_conntrack_info ctinfo,
1575                        unsigned int protoff,
1576                        unsigned char **data, AdmissionConfirm *acf)
1577 {
1578         int dir = CTINFO2DIR(ctinfo);
1579         int ret = 0;
1580         __be16 port;
1581         union nf_inet_addr addr;
1582         struct nf_conntrack_expect *exp;
1583         typeof(set_sig_addr_hook) set_sig_addr;
1584
1585         pr_debug("nf_ct_ras: ACF\n");
1586
1587         if (!get_h225_addr(ct, *data, &acf->destCallSignalAddress,
1588                            &addr, &port))
1589                 return 0;
1590
1591         if (!memcmp(&addr, &ct->tuplehash[dir].tuple.dst.u3, sizeof(addr))) {
1592                 /* Answering ACF */
1593                 set_sig_addr = rcu_dereference(set_sig_addr_hook);
1594                 if (set_sig_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1595                     ct->status & IPS_NAT_MASK)
1596                         return set_sig_addr(skb, ct, ctinfo, protoff, data,
1597                                             &acf->destCallSignalAddress, 1);
1598                 return 0;
1599         }
1600
1601         /* Need new expect */
1602         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1603                 return -1;
1604         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1605                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1606                           IPPROTO_TCP, NULL, &port);
1607         exp->flags = NF_CT_EXPECT_PERMANENT;
1608         exp->helper = nf_conntrack_helper_q931;
1609
1610         if (nf_ct_expect_related(exp) == 0) {
1611                 pr_debug("nf_ct_ras: expect Q.931 ");
1612                 nf_ct_dump_tuple(&exp->tuple);
1613         } else
1614                 ret = -1;
1615
1616         nf_ct_expect_put(exp);
1617
1618         return ret;
1619 }
1620
1621 /****************************************************************************/
1622 static int process_lrq(struct sk_buff *skb, struct nf_conn *ct,
1623                        enum ip_conntrack_info ctinfo,
1624                        unsigned int protoff,
1625                        unsigned char **data, LocationRequest *lrq)
1626 {
1627         typeof(set_ras_addr_hook) set_ras_addr;
1628
1629         pr_debug("nf_ct_ras: LRQ\n");
1630
1631         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1632         if (set_ras_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1633             ct->status & IPS_NAT_MASK)
1634                 return set_ras_addr(skb, ct, ctinfo, protoff, data,
1635                                     &lrq->replyAddress, 1);
1636         return 0;
1637 }
1638
1639 /****************************************************************************/
1640 static int process_lcf(struct sk_buff *skb, struct nf_conn *ct,
1641                        enum ip_conntrack_info ctinfo,
1642                        unsigned int protoff,
1643                        unsigned char **data, LocationConfirm *lcf)
1644 {
1645         int dir = CTINFO2DIR(ctinfo);
1646         int ret = 0;
1647         __be16 port;
1648         union nf_inet_addr addr;
1649         struct nf_conntrack_expect *exp;
1650
1651         pr_debug("nf_ct_ras: LCF\n");
1652
1653         if (!get_h225_addr(ct, *data, &lcf->callSignalAddress,
1654                            &addr, &port))
1655                 return 0;
1656
1657         /* Need new expect for call signal */
1658         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1659                 return -1;
1660         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1661                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1662                           IPPROTO_TCP, NULL, &port);
1663         exp->flags = NF_CT_EXPECT_PERMANENT;
1664         exp->helper = nf_conntrack_helper_q931;
1665
1666         if (nf_ct_expect_related(exp) == 0) {
1667                 pr_debug("nf_ct_ras: expect Q.931 ");
1668                 nf_ct_dump_tuple(&exp->tuple);
1669         } else
1670                 ret = -1;
1671
1672         nf_ct_expect_put(exp);
1673
1674         /* Ignore rasAddress */
1675
1676         return ret;
1677 }
1678
1679 /****************************************************************************/
1680 static int process_irr(struct sk_buff *skb, struct nf_conn *ct,
1681                        enum ip_conntrack_info ctinfo,
1682                        unsigned int protoff,
1683                        unsigned char **data, InfoRequestResponse *irr)
1684 {
1685         int ret;
1686         typeof(set_ras_addr_hook) set_ras_addr;
1687         typeof(set_sig_addr_hook) set_sig_addr;
1688
1689         pr_debug("nf_ct_ras: IRR\n");
1690
1691         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1692         if (set_ras_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1693             ct->status & IPS_NAT_MASK) {
1694                 ret = set_ras_addr(skb, ct, ctinfo, protoff, data,
1695                                    &irr->rasAddress, 1);
1696                 if (ret < 0)
1697                         return -1;
1698         }
1699
1700         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1701         if (set_sig_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1702             ct->status & IPS_NAT_MASK) {
1703                 ret = set_sig_addr(skb, ct, ctinfo, protoff, data,
1704                                         irr->callSignalAddress.item,
1705                                         irr->callSignalAddress.count);
1706                 if (ret < 0)
1707                         return -1;
1708         }
1709
1710         return 0;
1711 }
1712
1713 /****************************************************************************/
1714 static int process_ras(struct sk_buff *skb, struct nf_conn *ct,
1715                        enum ip_conntrack_info ctinfo,
1716                        unsigned int protoff,
1717                        unsigned char **data, RasMessage *ras)
1718 {
1719         switch (ras->choice) {
1720         case eRasMessage_gatekeeperRequest:
1721                 return process_grq(skb, ct, ctinfo, protoff, data,
1722                                    &ras->gatekeeperRequest);
1723         case eRasMessage_gatekeeperConfirm:
1724                 return process_gcf(skb, ct, ctinfo, protoff, data,
1725                                    &ras->gatekeeperConfirm);
1726         case eRasMessage_registrationRequest:
1727                 return process_rrq(skb, ct, ctinfo, protoff, data,
1728                                    &ras->registrationRequest);
1729         case eRasMessage_registrationConfirm:
1730                 return process_rcf(skb, ct, ctinfo, protoff, data,
1731                                    &ras->registrationConfirm);
1732         case eRasMessage_unregistrationRequest:
1733                 return process_urq(skb, ct, ctinfo, protoff, data,
1734                                    &ras->unregistrationRequest);
1735         case eRasMessage_admissionRequest:
1736                 return process_arq(skb, ct, ctinfo, protoff, data,
1737                                    &ras->admissionRequest);
1738         case eRasMessage_admissionConfirm:
1739                 return process_acf(skb, ct, ctinfo, protoff, data,
1740                                    &ras->admissionConfirm);
1741         case eRasMessage_locationRequest:
1742                 return process_lrq(skb, ct, ctinfo, protoff, data,
1743                                    &ras->locationRequest);
1744         case eRasMessage_locationConfirm:
1745                 return process_lcf(skb, ct, ctinfo, protoff, data,
1746                                    &ras->locationConfirm);
1747         case eRasMessage_infoRequestResponse:
1748                 return process_irr(skb, ct, ctinfo, protoff, data,
1749                                    &ras->infoRequestResponse);
1750         default:
1751                 pr_debug("nf_ct_ras: RAS message %d\n", ras->choice);
1752                 break;
1753         }
1754
1755         return 0;
1756 }
1757
1758 /****************************************************************************/
1759 static int ras_help(struct sk_buff *skb, unsigned int protoff,
1760                     struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1761 {
1762         static RasMessage ras;
1763         unsigned char *data;
1764         int datalen = 0;
1765         int ret;
1766
1767         pr_debug("nf_ct_ras: skblen = %u\n", skb->len);
1768
1769         spin_lock_bh(&nf_h323_lock);
1770
1771         /* Get UDP data */
1772         data = get_udp_data(skb, protoff, &datalen);
1773         if (data == NULL)
1774                 goto accept;
1775         pr_debug("nf_ct_ras: RAS message len=%d ", datalen);
1776         nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1777
1778         /* Decode RAS message */
1779         ret = DecodeRasMessage(data, datalen, &ras);
1780         if (ret < 0) {
1781                 pr_debug("nf_ct_ras: decoding error: %s\n",
1782                          ret == H323_ERROR_BOUND ?
1783                          "out of bound" : "out of range");
1784                 goto accept;
1785         }
1786
1787         /* Process RAS message */
1788         if (process_ras(skb, ct, ctinfo, protoff, &data, &ras) < 0)
1789                 goto drop;
1790
1791       accept:
1792         spin_unlock_bh(&nf_h323_lock);
1793         return NF_ACCEPT;
1794
1795       drop:
1796         spin_unlock_bh(&nf_h323_lock);
1797         net_info_ratelimited("nf_ct_ras: packet dropped\n");
1798         return NF_DROP;
1799 }
1800
1801 /****************************************************************************/
1802 static const struct nf_conntrack_expect_policy ras_exp_policy = {
1803         .max_expected           = 32,
1804         .timeout                = 240,
1805 };
1806
1807 static struct nf_conntrack_helper nf_conntrack_helper_ras[] __read_mostly = {
1808         {
1809                 .name                   = "RAS",
1810                 .me                     = THIS_MODULE,
1811                 .data_len               = sizeof(struct nf_ct_h323_master),
1812                 .tuple.src.l3num        = AF_INET,
1813                 .tuple.src.u.udp.port   = cpu_to_be16(RAS_PORT),
1814                 .tuple.dst.protonum     = IPPROTO_UDP,
1815                 .help                   = ras_help,
1816                 .expect_policy          = &ras_exp_policy,
1817         },
1818         {
1819                 .name                   = "RAS",
1820                 .me                     = THIS_MODULE,
1821                 .data_len               = sizeof(struct nf_ct_h323_master),
1822                 .tuple.src.l3num        = AF_INET6,
1823                 .tuple.src.u.udp.port   = cpu_to_be16(RAS_PORT),
1824                 .tuple.dst.protonum     = IPPROTO_UDP,
1825                 .help                   = ras_help,
1826                 .expect_policy          = &ras_exp_policy,
1827         },
1828 };
1829
1830 /****************************************************************************/
1831 static void __exit nf_conntrack_h323_fini(void)
1832 {
1833         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[1]);
1834         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1835         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1836         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1837         nf_conntrack_helper_unregister(&nf_conntrack_helper_h245);
1838         kfree(h323_buffer);
1839         pr_debug("nf_ct_h323: fini\n");
1840 }
1841
1842 /****************************************************************************/
1843 static int __init nf_conntrack_h323_init(void)
1844 {
1845         int ret;
1846
1847         h323_buffer = kmalloc(65536, GFP_KERNEL);
1848         if (!h323_buffer)
1849                 return -ENOMEM;
1850         ret = nf_conntrack_helper_register(&nf_conntrack_helper_h245);
1851         if (ret < 0)
1852                 goto err1;
1853         ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[0]);
1854         if (ret < 0)
1855                 goto err2;
1856         ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[1]);
1857         if (ret < 0)
1858                 goto err3;
1859         ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[0]);
1860         if (ret < 0)
1861                 goto err4;
1862         ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[1]);
1863         if (ret < 0)
1864                 goto err5;
1865         pr_debug("nf_ct_h323: init success\n");
1866         return 0;
1867
1868 err5:
1869         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1870 err4:
1871         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1872 err3:
1873         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1874 err2:
1875         nf_conntrack_helper_unregister(&nf_conntrack_helper_h245);
1876 err1:
1877         kfree(h323_buffer);
1878         return ret;
1879 }
1880
1881 /****************************************************************************/
1882 module_init(nf_conntrack_h323_init);
1883 module_exit(nf_conntrack_h323_fini);
1884
1885 EXPORT_SYMBOL_GPL(get_h225_addr);
1886 EXPORT_SYMBOL_GPL(set_h245_addr_hook);
1887 EXPORT_SYMBOL_GPL(set_h225_addr_hook);
1888 EXPORT_SYMBOL_GPL(set_sig_addr_hook);
1889 EXPORT_SYMBOL_GPL(set_ras_addr_hook);
1890 EXPORT_SYMBOL_GPL(nat_rtp_rtcp_hook);
1891 EXPORT_SYMBOL_GPL(nat_t120_hook);
1892 EXPORT_SYMBOL_GPL(nat_h245_hook);
1893 EXPORT_SYMBOL_GPL(nat_callforwarding_hook);
1894 EXPORT_SYMBOL_GPL(nat_q931_hook);
1895
1896 MODULE_AUTHOR("Jing Min Zhao <zhaojingmin@users.sourceforge.net>");
1897 MODULE_DESCRIPTION("H.323 connection tracking helper");
1898 MODULE_LICENSE("GPL");
1899 MODULE_ALIAS("ip_conntrack_h323");
1900 MODULE_ALIAS_NFCT_HELPER("RAS");
1901 MODULE_ALIAS_NFCT_HELPER("Q.931");
1902 MODULE_ALIAS_NFCT_HELPER("H.245");