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  * Copyright (c) 2006-2012 Patrick McHardy <kaber@trash.net>
   6  *
   7  * This source code is licensed under General Public License version 2.
   8  *
   9  * Based on the 'brute force' H.323 connection tracking module by
  10  * Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
  11  *
  12  * For more information, please see http://nath323.sourceforge.net/
  13  */
  14
  15 #include <linux/module.h>
  16 #include <linux/moduleparam.h>
  17 #include <linux/ctype.h>
  18 #include <linux/inet.h>
  19 #include <linux/in.h>
  20 #include <linux/ip.h>
  21 #include <linux/slab.h>
  22 #include <linux/udp.h>
  23 #include <linux/tcp.h>
  24 #include <linux/skbuff.h>
  25 #include <net/route.h>
  26 #include <net/ip6_route.h>
  27
  28 #include <net/netfilter/nf_conntrack.h>
  29 #include <net/netfilter/nf_conntrack_core.h>
  30 #include <net/netfilter/nf_conntrack_tuple.h>
  31 #include <net/netfilter/nf_conntrack_expect.h>
  32 #include <net/netfilter/nf_conntrack_ecache.h>
  33 #include <net/netfilter/nf_conntrack_helper.h>
  34 #include <net/netfilter/nf_conntrack_zones.h>
  35 #include <linux/netfilter/nf_conntrack_h323.h>
  36
  37 /* Parameters */
  38 static unsigned int default_rrq_ttl __read_mostly = 300;
  39 module_param(default_rrq_ttl, uint, 0600);
  40 MODULE_PARM_DESC(default_rrq_ttl, "use this TTL if it's missing in RRQ");
  41
  42 static int gkrouted_only __read_mostly = 1;
  43 module_param(gkrouted_only, int, 0600);
  44 MODULE_PARM_DESC(gkrouted_only, "only accept calls from gatekeeper");
  45
  46 static bool callforward_filter __read_mostly = true;
  47 module_param(callforward_filter, bool, 0600);
  48 MODULE_PARM_DESC(callforward_filter, "only create call forwarding expectations "
  49                                      "if both endpoints are on different sides "
  50                                      "(determined by routing information)");
  51
  52 /* Hooks for NAT */
  53 int (*set_h245_addr_hook) (struct sk_buff *skb, unsigned int protoff,
  54                            unsigned char **data, int dataoff,
  55                            H245_TransportAddress *taddr,
  56                            union nf_inet_addr *addr, __be16 port)
  57                            __read_mostly;
  58 int (*set_h225_addr_hook) (struct sk_buff *skb, unsigned int protoff,
  59                            unsigned char **data, int dataoff,
  60                            TransportAddress *taddr,
  61                            union nf_inet_addr *addr, __be16 port)
  62                            __read_mostly;
  63 int (*set_sig_addr_hook) (struct sk_buff *skb,
  64                           struct nf_conn *ct,
  65                           enum ip_conntrack_info ctinfo,
  66                           unsigned int protoff, unsigned char **data,
  67                           TransportAddress *taddr, int count) __read_mostly;
  68 int (*set_ras_addr_hook) (struct sk_buff *skb,
  69                           struct nf_conn *ct,
  70                           enum ip_conntrack_info ctinfo,
  71                           unsigned int protoff, unsigned char **data,
  72                           TransportAddress *taddr, int count) __read_mostly;
  73 int (*nat_rtp_rtcp_hook) (struct sk_buff *skb,
  74                           struct nf_conn *ct,
  75                           enum ip_conntrack_info ctinfo,
  76                           unsigned int protoff,
  77                           unsigned char **data, int dataoff,
  78                           H245_TransportAddress *taddr,
  79                           __be16 port, __be16 rtp_port,
  80                           struct nf_conntrack_expect *rtp_exp,
  81                           struct nf_conntrack_expect *rtcp_exp) __read_mostly;
  82 int (*nat_t120_hook) (struct sk_buff *skb,
  83                       struct nf_conn *ct,
  84                       enum ip_conntrack_info ctinfo,
  85                       unsigned int protoff,
  86                       unsigned char **data, int dataoff,
  87                       H245_TransportAddress *taddr, __be16 port,
  88                       struct nf_conntrack_expect *exp) __read_mostly;
  89 int (*nat_h245_hook) (struct sk_buff *skb,
  90                       struct nf_conn *ct,
  91                       enum ip_conntrack_info ctinfo,
  92                       unsigned int protoff,
  93                       unsigned char **data, int dataoff,
  94                       TransportAddress *taddr, __be16 port,
  95                       struct nf_conntrack_expect *exp) __read_mostly;
  96 int (*nat_callforwarding_hook) (struct sk_buff *skb,
  97                                 struct nf_conn *ct,
  98                                 enum ip_conntrack_info ctinfo,
  99                                 unsigned int protoff,
 100                                 unsigned char **data, int dataoff,
 101                                 TransportAddress *taddr, __be16 port,
 102                                 struct nf_conntrack_expect *exp) __read_mostly;
 103 int (*nat_q931_hook) (struct sk_buff *skb,
 104                       struct nf_conn *ct,
 105                       enum ip_conntrack_info ctinfo,
 106                       unsigned int protoff,
 107                       unsigned char **data, TransportAddress *taddr, int idx,
 108                       __be16 port, struct nf_conntrack_expect *exp)
 109                       __read_mostly;
 110
 111 static DEFINE_SPINLOCK(nf_h323_lock);
 112 static char *h323_buffer;
 113
 114 static struct nf_conntrack_helper nf_conntrack_helper_h245;
 115 static struct nf_conntrack_helper nf_conntrack_helper_q931[];
 116 static struct nf_conntrack_helper nf_conntrack_helper_ras[];
 117
 118 /****************************************************************************/
 119 static int get_tpkt_data(struct sk_buff *skb, unsigned int protoff,
 120                          struct nf_conn *ct, enum ip_conntrack_info ctinfo,
 121                          unsigned char **data, int *datalen, int *dataoff)
 122 {
 123         struct nf_ct_h323_master *info = nfct_help_data(ct);
 124         int dir = CTINFO2DIR(ctinfo);
 125         const struct tcphdr *th;
 126         struct tcphdr _tcph;
 127         int tcpdatalen;
 128         int tcpdataoff;
 129         unsigned char *tpkt;
 130         int tpktlen;
 131         int tpktoff;
 132
 133         /* Get TCP header */
 134         th = skb_header_pointer(skb, protoff, sizeof(_tcph), &_tcph);
 135         if (th == NULL)
 136                 return 0;
 137
 138         /* Get TCP data offset */
 139         tcpdataoff = protoff + th->doff * 4;
 140
 141         /* Get TCP data length */
 142         tcpdatalen = skb->len - tcpdataoff;
 143         if (tcpdatalen <= 0)    /* No TCP data */
 144                 goto clear_out;
 145
 146         if (*data == NULL) {    /* first TPKT */
 147                 /* Get first TPKT pointer */
 148                 tpkt = skb_header_pointer(skb, tcpdataoff, tcpdatalen,
 149                                           h323_buffer);
 150                 BUG_ON(tpkt == NULL);
 151
 152                 /* Validate TPKT identifier */
 153                 if (tcpdatalen < 4 || tpkt[0] != 0x03 || tpkt[1] != 0) {
 154                         /* Netmeeting sends TPKT header and data separately */
 155                         if (info->tpkt_len[dir] > 0) {
 156                                 pr_debug("nf_ct_h323: previous packet "
 157                                          "indicated separate TPKT data of %hu "
 158                                          "bytes\n", info->tpkt_len[dir]);
 159                                 if (info->tpkt_len[dir] <= tcpdatalen) {
 160                                         /* Yes, there was a TPKT header
 161                                          * received */
 162                                         *data = tpkt;
 163                                         *datalen = info->tpkt_len[dir];
 164                                         *dataoff = 0;
 165                                         goto out;
 166                                 }
 167
 168                                 /* Fragmented TPKT */
 169                                 pr_debug("nf_ct_h323: fragmented TPKT\n");
 170                                 goto clear_out;
 171                         }
 172
 173                         /* It is not even a TPKT */
 174                         return 0;
 175                 }
 176                 tpktoff = 0;
 177         } else {                /* Next TPKT */
 178                 tpktoff = *dataoff + *datalen;
 179                 tcpdatalen -= tpktoff;
 180                 if (tcpdatalen <= 4)    /* No more TPKT */
 181                         goto clear_out;
 182                 tpkt = *data + *datalen;
 183
 184                 /* Validate TPKT identifier */
 185                 if (tpkt[0] != 0x03 || tpkt[1] != 0)
 186                         goto clear_out;
 187         }
 188
 189         /* Validate TPKT length */
 190         tpktlen = tpkt[2] * 256 + tpkt[3];
 191         if (tpktlen < 4)
 192                 goto clear_out;
 193         if (tpktlen > tcpdatalen) {
 194                 if (tcpdatalen == 4) {  /* Separate TPKT header */
 195                         /* Netmeeting sends TPKT header and data separately */
 196                         pr_debug("nf_ct_h323: separate TPKT header indicates "
 197                                  "there will be TPKT data of %hu bytes\n",
 198                                  tpktlen - 4);
 199                         info->tpkt_len[dir] = tpktlen - 4;
 200                         return 0;
 201                 }
 202
 203                 pr_debug("nf_ct_h323: incomplete TPKT (fragmented?)\n");
 204                 goto clear_out;
 205         }
 206
 207         /* This is the encapsulated data */
 208         *data = tpkt + 4;
 209         *datalen = tpktlen - 4;
 210         *dataoff = tpktoff + 4;
 211
 212       out:
 213         /* Clear TPKT length */
 214         info->tpkt_len[dir] = 0;
 215         return 1;
 216
 217       clear_out:
 218         info->tpkt_len[dir] = 0;
 219         return 0;
 220 }
 221
 222 /****************************************************************************/
 223 static int get_h245_addr(struct nf_conn *ct, const unsigned char *data,
 224                          H245_TransportAddress *taddr,
 225                          union nf_inet_addr *addr, __be16 *port)
 226 {
 227         const unsigned char *p;
 228         int len;
 229
 230         if (taddr->choice != eH245_TransportAddress_unicastAddress)
 231                 return 0;
 232
 233         switch (taddr->unicastAddress.choice) {
 234         case eUnicastAddress_iPAddress:
 235                 if (nf_ct_l3num(ct) != AF_INET)
 236                         return 0;
 237                 p = data + taddr->unicastAddress.iPAddress.network;
 238                 len = 4;
 239                 break;
 240         case eUnicastAddress_iP6Address:
 241                 if (nf_ct_l3num(ct) != AF_INET6)
 242                         return 0;
 243                 p = data + taddr->unicastAddress.iP6Address.network;
 244                 len = 16;
 245                 break;
 246         default:
 247                 return 0;
 248         }
 249
 250         memcpy(addr, p, len);
 251         memset((void *)addr + len, 0, sizeof(*addr) - len);
 252         memcpy(port, p + len, sizeof(__be16));
 253
 254         return 1;
 255 }
 256
 257 /****************************************************************************/
 258 static int expect_rtp_rtcp(struct sk_buff *skb, struct nf_conn *ct,
 259                            enum ip_conntrack_info ctinfo,
 260                            unsigned int protoff,
 261                            unsigned char **data, int dataoff,
 262                            H245_TransportAddress *taddr)
 263 {
 264         int dir = CTINFO2DIR(ctinfo);
 265         int ret = 0;
 266         __be16 port;
 267         __be16 rtp_port, rtcp_port;
 268         union nf_inet_addr addr;
 269         struct nf_conntrack_expect *rtp_exp;
 270         struct nf_conntrack_expect *rtcp_exp;
 271         typeof(nat_rtp_rtcp_hook) nat_rtp_rtcp;
 272
 273         /* Read RTP or RTCP address */
 274         if (!get_h245_addr(ct, *data, taddr, &addr, &port) ||
 275             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
 276             port == 0)
 277                 return 0;
 278
 279         /* RTP port is even */
 280         rtp_port = port & ~htons(1);
 281         rtcp_port = port | htons(1);
 282
 283         /* Create expect for RTP */
 284         if ((rtp_exp = nf_ct_expect_alloc(ct)) == NULL)
 285                 return -1;
 286         nf_ct_expect_init(rtp_exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 287                           &ct->tuplehash[!dir].tuple.src.u3,
 288                           &ct->tuplehash[!dir].tuple.dst.u3,
 289                           IPPROTO_UDP, NULL, &rtp_port);
 290
 291         /* Create expect for RTCP */
 292         if ((rtcp_exp = nf_ct_expect_alloc(ct)) == NULL) {
 293                 nf_ct_expect_put(rtp_exp);
 294                 return -1;
 295         }
 296         nf_ct_expect_init(rtcp_exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 297                           &ct->tuplehash[!dir].tuple.src.u3,
 298                           &ct->tuplehash[!dir].tuple.dst.u3,
 299                           IPPROTO_UDP, NULL, &rtcp_port);
 300
 301         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 302                    &ct->tuplehash[!dir].tuple.dst.u3,
 303                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 304                    (nat_rtp_rtcp = rcu_dereference(nat_rtp_rtcp_hook)) &&
 305                    nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 306                    ct->status & IPS_NAT_MASK) {
 307                 /* NAT needed */
 308                 ret = nat_rtp_rtcp(skb, ct, ctinfo, protoff, data, dataoff,
 309                                    taddr, port, rtp_port, rtp_exp, rtcp_exp);
 310         } else {                /* Conntrack only */
 311                 if (nf_ct_expect_related(rtp_exp) == 0) {
 312                         if (nf_ct_expect_related(rtcp_exp) == 0) {
 313                                 pr_debug("nf_ct_h323: expect RTP ");
 314                                 nf_ct_dump_tuple(&rtp_exp->tuple);
 315                                 pr_debug("nf_ct_h323: expect RTCP ");
 316                                 nf_ct_dump_tuple(&rtcp_exp->tuple);
 317                         } else {
 318                                 nf_ct_unexpect_related(rtp_exp);
 319                                 ret = -1;
 320                         }
 321                 } else
 322                         ret = -1;
 323         }
 324
 325         nf_ct_expect_put(rtp_exp);
 326         nf_ct_expect_put(rtcp_exp);
 327
 328         return ret;
 329 }
 330
 331 /****************************************************************************/
 332 static int expect_t120(struct sk_buff *skb,
 333                        struct nf_conn *ct,
 334                        enum ip_conntrack_info ctinfo,
 335                        unsigned int protoff,
 336                        unsigned char **data, int dataoff,
 337                        H245_TransportAddress *taddr)
 338 {
 339         int dir = CTINFO2DIR(ctinfo);
 340         int ret = 0;
 341         __be16 port;
 342         union nf_inet_addr addr;
 343         struct nf_conntrack_expect *exp;
 344         typeof(nat_t120_hook) nat_t120;
 345
 346         /* Read T.120 address */
 347         if (!get_h245_addr(ct, *data, taddr, &addr, &port) ||
 348             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
 349             port == 0)
 350                 return 0;
 351
 352         /* Create expect for T.120 connections */
 353         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
 354                 return -1;
 355         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 356                           &ct->tuplehash[!dir].tuple.src.u3,
 357                           &ct->tuplehash[!dir].tuple.dst.u3,
 358                           IPPROTO_TCP, NULL, &port);
 359         exp->flags = NF_CT_EXPECT_PERMANENT;    /* Accept multiple channels */
 360
 361         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 362                    &ct->tuplehash[!dir].tuple.dst.u3,
 363                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 364             (nat_t120 = rcu_dereference(nat_t120_hook)) &&
 365             nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 366             ct->status & IPS_NAT_MASK) {
 367                 /* NAT needed */
 368                 ret = nat_t120(skb, ct, ctinfo, protoff, data, dataoff, taddr,
 369                                port, exp);
 370         } else {                /* Conntrack only */
 371                 if (nf_ct_expect_related(exp) == 0) {
 372                         pr_debug("nf_ct_h323: expect T.120 ");
 373                         nf_ct_dump_tuple(&exp->tuple);
 374                 } else
 375                         ret = -1;
 376         }
 377
 378         nf_ct_expect_put(exp);
 379
 380         return ret;
 381 }
 382
 383 /****************************************************************************/
 384 static int process_h245_channel(struct sk_buff *skb,
 385                                 struct nf_conn *ct,
 386                                 enum ip_conntrack_info ctinfo,
 387                                 unsigned int protoff,
 388                                 unsigned char **data, int dataoff,
 389                                 H2250LogicalChannelParameters *channel)
 390 {
 391         int ret;
 392
 393         if (channel->options & eH2250LogicalChannelParameters_mediaChannel) {
 394                 /* RTP */
 395                 ret = expect_rtp_rtcp(skb, ct, ctinfo, protoff, data, dataoff,
 396                                       &channel->mediaChannel);
 397                 if (ret < 0)
 398                         return -1;
 399         }
 400
 401         if (channel->
 402             options & eH2250LogicalChannelParameters_mediaControlChannel) {
 403                 /* RTCP */
 404                 ret = expect_rtp_rtcp(skb, ct, ctinfo, protoff, data, dataoff,
 405                                       &channel->mediaControlChannel);
 406                 if (ret < 0)
 407                         return -1;
 408         }
 409
 410         return 0;
 411 }
 412
 413 /****************************************************************************/
 414 static int process_olc(struct sk_buff *skb, struct nf_conn *ct,
 415                        enum ip_conntrack_info ctinfo,
 416                        unsigned int protoff,
 417                        unsigned char **data, int dataoff,
 418                        OpenLogicalChannel *olc)
 419 {
 420         int ret;
 421
 422         pr_debug("nf_ct_h323: OpenLogicalChannel\n");
 423
 424         if (olc->forwardLogicalChannelParameters.multiplexParameters.choice ==
 425             eOpenLogicalChannel_forwardLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters)
 426         {
 427                 ret = process_h245_channel(skb, ct, ctinfo,
 428                                            protoff, data, dataoff,
 429                                            &olc->
 430                                            forwardLogicalChannelParameters.
 431                                            multiplexParameters.
 432                                            h2250LogicalChannelParameters);
 433                 if (ret < 0)
 434                         return -1;
 435         }
 436
 437         if ((olc->options &
 438              eOpenLogicalChannel_reverseLogicalChannelParameters) &&
 439             (olc->reverseLogicalChannelParameters.options &
 440              eOpenLogicalChannel_reverseLogicalChannelParameters_multiplexParameters)
 441             && (olc->reverseLogicalChannelParameters.multiplexParameters.
 442                 choice ==
 443                 eOpenLogicalChannel_reverseLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters))
 444         {
 445                 ret =
 446                     process_h245_channel(skb, ct, ctinfo,
 447                                          protoff, data, dataoff,
 448                                          &olc->
 449                                          reverseLogicalChannelParameters.
 450                                          multiplexParameters.
 451                                          h2250LogicalChannelParameters);
 452                 if (ret < 0)
 453                         return -1;
 454         }
 455
 456         if ((olc->options & eOpenLogicalChannel_separateStack) &&
 457             olc->forwardLogicalChannelParameters.dataType.choice ==
 458             eDataType_data &&
 459             olc->forwardLogicalChannelParameters.dataType.data.application.
 460             choice == eDataApplicationCapability_application_t120 &&
 461             olc->forwardLogicalChannelParameters.dataType.data.application.
 462             t120.choice == eDataProtocolCapability_separateLANStack &&
 463             olc->separateStack.networkAddress.choice ==
 464             eNetworkAccessParameters_networkAddress_localAreaAddress) {
 465                 ret = expect_t120(skb, ct, ctinfo, protoff, data, dataoff,
 466                                   &olc->separateStack.networkAddress.
 467                                   localAreaAddress);
 468                 if (ret < 0)
 469                         return -1;
 470         }
 471
 472         return 0;
 473 }
 474
 475 /****************************************************************************/
 476 static int process_olca(struct sk_buff *skb, struct nf_conn *ct,
 477                         enum ip_conntrack_info ctinfo,
 478                         unsigned int protoff, unsigned char **data, int dataoff,
 479                         OpenLogicalChannelAck *olca)
 480 {
 481         H2250LogicalChannelAckParameters *ack;
 482         int ret;
 483
 484         pr_debug("nf_ct_h323: OpenLogicalChannelAck\n");
 485
 486         if ((olca->options &
 487              eOpenLogicalChannelAck_reverseLogicalChannelParameters) &&
 488             (olca->reverseLogicalChannelParameters.options &
 489              eOpenLogicalChannelAck_reverseLogicalChannelParameters_multiplexParameters)
 490             && (olca->reverseLogicalChannelParameters.multiplexParameters.
 491                 choice ==
 492                 eOpenLogicalChannelAck_reverseLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters))
 493         {
 494                 ret = process_h245_channel(skb, ct, ctinfo,
 495                                            protoff, data, dataoff,
 496                                            &olca->
 497                                            reverseLogicalChannelParameters.
 498                                            multiplexParameters.
 499                                            h2250LogicalChannelParameters);
 500                 if (ret < 0)
 501                         return -1;
 502         }
 503
 504         if ((olca->options &
 505              eOpenLogicalChannelAck_forwardMultiplexAckParameters) &&
 506             (olca->forwardMultiplexAckParameters.choice ==
 507              eOpenLogicalChannelAck_forwardMultiplexAckParameters_h2250LogicalChannelAckParameters))
 508         {
 509                 ack = &olca->forwardMultiplexAckParameters.
 510                     h2250LogicalChannelAckParameters;
 511                 if (ack->options &
 512                     eH2250LogicalChannelAckParameters_mediaChannel) {
 513                         /* RTP */
 514                         ret = expect_rtp_rtcp(skb, ct, ctinfo,
 515                                               protoff, data, dataoff,
 516                                               &ack->mediaChannel);
 517                         if (ret < 0)
 518                                 return -1;
 519                 }
 520
 521                 if (ack->options &
 522                     eH2250LogicalChannelAckParameters_mediaControlChannel) {
 523                         /* RTCP */
 524                         ret = expect_rtp_rtcp(skb, ct, ctinfo,
 525                                               protoff, data, dataoff,
 526                                               &ack->mediaControlChannel);
 527                         if (ret < 0)
 528                                 return -1;
 529                 }
 530         }
 531
 532         if ((olca->options & eOpenLogicalChannelAck_separateStack) &&
 533                 olca->separateStack.networkAddress.choice ==
 534                 eNetworkAccessParameters_networkAddress_localAreaAddress) {
 535                 ret = expect_t120(skb, ct, ctinfo, protoff, data, dataoff,
 536                                   &olca->separateStack.networkAddress.
 537                                   localAreaAddress);
 538                 if (ret < 0)
 539                         return -1;
 540         }
 541
 542         return 0;
 543 }
 544
 545 /****************************************************************************/
 546 static int process_h245(struct sk_buff *skb, struct nf_conn *ct,
 547                         enum ip_conntrack_info ctinfo,
 548                         unsigned int protoff, unsigned char **data, int dataoff,
 549                         MultimediaSystemControlMessage *mscm)
 550 {
 551         switch (mscm->choice) {
 552         case eMultimediaSystemControlMessage_request:
 553                 if (mscm->request.choice ==
 554                     eRequestMessage_openLogicalChannel) {
 555                         return process_olc(skb, ct, ctinfo,
 556                                            protoff, data, dataoff,
 557                                            &mscm->request.openLogicalChannel);
 558                 }
 559                 pr_debug("nf_ct_h323: H.245 Request %d\n",
 560                          mscm->request.choice);
 561                 break;
 562         case eMultimediaSystemControlMessage_response:
 563                 if (mscm->response.choice ==
 564                     eResponseMessage_openLogicalChannelAck) {
 565                         return process_olca(skb, ct, ctinfo,
 566                                             protoff, data, dataoff,
 567                                             &mscm->response.
 568                                             openLogicalChannelAck);
 569                 }
 570                 pr_debug("nf_ct_h323: H.245 Response %d\n",
 571                          mscm->response.choice);
 572                 break;
 573         default:
 574                 pr_debug("nf_ct_h323: H.245 signal %d\n", mscm->choice);
 575                 break;
 576         }
 577
 578         return 0;
 579 }
 580
 581 /****************************************************************************/
 582 static int h245_help(struct sk_buff *skb, unsigned int protoff,
 583                      struct nf_conn *ct, enum ip_conntrack_info ctinfo)
 584 {
 585         static MultimediaSystemControlMessage mscm;
 586         unsigned char *data = NULL;
 587         int datalen;
 588         int dataoff;
 589         int ret;
 590
 591         /* Until there's been traffic both ways, don't look in packets. */
 592         if (ctinfo != IP_CT_ESTABLISHED && ctinfo != IP_CT_ESTABLISHED_REPLY)
 593                 return NF_ACCEPT;
 594
 595         pr_debug("nf_ct_h245: skblen = %u\n", skb->len);
 596
 597         spin_lock_bh(&nf_h323_lock);
 598
 599         /* Process each TPKT */
 600         while (get_tpkt_data(skb, protoff, ct, ctinfo,
 601                              &data, &datalen, &dataoff)) {
 602                 pr_debug("nf_ct_h245: TPKT len=%d ", datalen);
 603                 nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
 604
 605                 /* Decode H.245 signal */
 606                 ret = DecodeMultimediaSystemControlMessage(data, datalen,
 607                                                            &mscm);
 608                 if (ret < 0) {
 609                         pr_debug("nf_ct_h245: decoding error: %s\n",
 610                                  ret == H323_ERROR_BOUND ?
 611                                  "out of bound" : "out of range");
 612                         /* We don't drop when decoding error */
 613                         break;
 614                 }
 615
 616                 /* Process H.245 signal */
 617                 if (process_h245(skb, ct, ctinfo, protoff,
 618                                  &data, dataoff, &mscm) < 0)
 619                         goto drop;
 620         }
 621
 622         spin_unlock_bh(&nf_h323_lock);
 623         return NF_ACCEPT;
 624
 625       drop:
 626         spin_unlock_bh(&nf_h323_lock);
 627         nf_ct_helper_log(skb, ct, "cannot process H.245 message");
 628         return NF_DROP;
 629 }
 630
 631 /****************************************************************************/
 632 static const struct nf_conntrack_expect_policy h245_exp_policy = {
 633         .max_expected   = H323_RTP_CHANNEL_MAX * 4 + 2 /* T.120 */,
 634         .timeout        = 240,
 635 };
 636
 637 static struct nf_conntrack_helper nf_conntrack_helper_h245 __read_mostly = {
 638         .name                   = "H.245",
 639         .me                     = THIS_MODULE,
 640         .data_len               = sizeof(struct nf_ct_h323_master),
 641         .tuple.src.l3num        = AF_UNSPEC,
 642         .tuple.dst.protonum     = IPPROTO_UDP,
 643         .help                   = h245_help,
 644         .expect_policy          = &h245_exp_policy,
 645 };
 646
 647 /****************************************************************************/
 648 int get_h225_addr(struct nf_conn *ct, unsigned char *data,
 649                   TransportAddress *taddr,
 650                   union nf_inet_addr *addr, __be16 *port)
 651 {
 652         const unsigned char *p;
 653         int len;
 654
 655         switch (taddr->choice) {
 656         case eTransportAddress_ipAddress:
 657                 if (nf_ct_l3num(ct) != AF_INET)
 658                         return 0;
 659                 p = data + taddr->ipAddress.ip;
 660                 len = 4;
 661                 break;
 662         case eTransportAddress_ip6Address:
 663                 if (nf_ct_l3num(ct) != AF_INET6)
 664                         return 0;
 665                 p = data + taddr->ip6Address.ip;
 666                 len = 16;
 667                 break;
 668         default:
 669                 return 0;
 670         }
 671
 672         memcpy(addr, p, len);
 673         memset((void *)addr + len, 0, sizeof(*addr) - len);
 674         memcpy(port, p + len, sizeof(__be16));
 675
 676         return 1;
 677 }
 678
 679 /****************************************************************************/
 680 static int expect_h245(struct sk_buff *skb, struct nf_conn *ct,
 681                        enum ip_conntrack_info ctinfo,
 682                        unsigned int protoff, unsigned char **data, int dataoff,
 683                        TransportAddress *taddr)
 684 {
 685         int dir = CTINFO2DIR(ctinfo);
 686         int ret = 0;
 687         __be16 port;
 688         union nf_inet_addr addr;
 689         struct nf_conntrack_expect *exp;
 690         typeof(nat_h245_hook) nat_h245;
 691
 692         /* Read h245Address */
 693         if (!get_h225_addr(ct, *data, taddr, &addr, &port) ||
 694             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
 695             port == 0)
 696                 return 0;
 697
 698         /* Create expect for h245 connection */
 699         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
 700                 return -1;
 701         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 702                           &ct->tuplehash[!dir].tuple.src.u3,
 703                           &ct->tuplehash[!dir].tuple.dst.u3,
 704                           IPPROTO_TCP, NULL, &port);
 705         exp->helper = &nf_conntrack_helper_h245;
 706
 707         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 708                    &ct->tuplehash[!dir].tuple.dst.u3,
 709                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 710             (nat_h245 = rcu_dereference(nat_h245_hook)) &&
 711             nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 712             ct->status & IPS_NAT_MASK) {
 713                 /* NAT needed */
 714                 ret = nat_h245(skb, ct, ctinfo, protoff, data, dataoff, taddr,
 715                                port, exp);
 716         } else {                /* Conntrack only */
 717                 if (nf_ct_expect_related(exp) == 0) {
 718                         pr_debug("nf_ct_q931: expect H.245 ");
 719                         nf_ct_dump_tuple(&exp->tuple);
 720                 } else
 721                         ret = -1;
 722         }
 723
 724         nf_ct_expect_put(exp);
 725
 726         return ret;
 727 }
 728
 729 /* If the calling party is on the same side of the forward-to party,
 730  * we don't need to track the second call */
 731 static int callforward_do_filter(struct net *net,
 732                                  const union nf_inet_addr *src,
 733                                  const union nf_inet_addr *dst,
 734                                  u_int8_t family)
 735 {
 736         const struct nf_afinfo *afinfo;
 737         int ret = 0;
 738
 739         /* rcu_read_lock()ed by nf_hook_thresh */
 740         afinfo = nf_get_afinfo(family);
 741         if (!afinfo)
 742                 return 0;
 743
 744         switch (family) {
 745         case AF_INET: {
 746                 struct flowi4 fl1, fl2;
 747                 struct rtable *rt1, *rt2;
 748
 749                 memset(&fl1, 0, sizeof(fl1));
 750                 fl1.daddr = src->ip;
 751
 752                 memset(&fl2, 0, sizeof(fl2));
 753                 fl2.daddr = dst->ip;
 754                 if (!afinfo->route(net, (struct dst_entry **)&rt1,
 755                                    flowi4_to_flowi(&fl1), false)) {
 756                         if (!afinfo->route(net, (struct dst_entry **)&rt2,
 757                                            flowi4_to_flowi(&fl2), false)) {
 758                                 if (rt_nexthop(rt1, fl1.daddr) ==
 759                                     rt_nexthop(rt2, fl2.daddr) &&
 760                                     rt1->dst.dev  == rt2->dst.dev)
 761                                         ret = 1;
 762                                 dst_release(&rt2->dst);
 763                         }
 764                         dst_release(&rt1->dst);
 765                 }
 766                 break;
 767         }
 768 #if IS_ENABLED(CONFIG_NF_CONNTRACK_IPV6)
 769         case AF_INET6: {
 770                 struct flowi6 fl1, fl2;
 771                 struct rt6_info *rt1, *rt2;
 772
 773                 memset(&fl1, 0, sizeof(fl1));
 774                 fl1.daddr = src->in6;
 775
 776                 memset(&fl2, 0, sizeof(fl2));
 777                 fl2.daddr = dst->in6;
 778                 if (!afinfo->route(net, (struct dst_entry **)&rt1,
 779                                    flowi6_to_flowi(&fl1), false)) {
 780                         if (!afinfo->route(net, (struct dst_entry **)&rt2,
 781                                            flowi6_to_flowi(&fl2), false)) {
 782                                 if (ipv6_addr_equal(rt6_nexthop(rt1, &fl1.daddr),
 783                                                     rt6_nexthop(rt2, &fl2.daddr)) &&
 784                                     rt1->dst.dev == rt2->dst.dev)
 785                                         ret = 1;
 786                                 dst_release(&rt2->dst);
 787                         }
 788                         dst_release(&rt1->dst);
 789                 }
 790                 break;
 791         }
 792 #endif
 793         }
 794         return ret;
 795
 796 }
 797
 798 /****************************************************************************/
 799 static int expect_callforwarding(struct sk_buff *skb,
 800                                  struct nf_conn *ct,
 801                                  enum ip_conntrack_info ctinfo,
 802                                  unsigned int protoff,
 803                                  unsigned char **data, int dataoff,
 804                                  TransportAddress *taddr)
 805 {
 806         int dir = CTINFO2DIR(ctinfo);
 807         int ret = 0;
 808         __be16 port;
 809         union nf_inet_addr addr;
 810         struct nf_conntrack_expect *exp;
 811         struct net *net = nf_ct_net(ct);
 812         typeof(nat_callforwarding_hook) nat_callforwarding;
 813
 814         /* Read alternativeAddress */
 815         if (!get_h225_addr(ct, *data, taddr, &addr, &port) || port == 0)
 816                 return 0;
 817
 818         /* If the calling party is on the same side of the forward-to party,
 819          * we don't need to track the second call */
 820         if (callforward_filter &&
 821             callforward_do_filter(net, &addr, &ct->tuplehash[!dir].tuple.src.u3,
 822                                   nf_ct_l3num(ct))) {
 823                 pr_debug("nf_ct_q931: Call Forwarding not tracked\n");
 824                 return 0;
 825         }
 826
 827         /* Create expect for the second call leg */
 828         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
 829                 return -1;
 830         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 831                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
 832                           IPPROTO_TCP, NULL, &port);
 833         exp->helper = nf_conntrack_helper_q931;
 834
 835         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 836                    &ct->tuplehash[!dir].tuple.dst.u3,
 837                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 838             (nat_callforwarding = rcu_dereference(nat_callforwarding_hook)) &&
 839             nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 840             ct->status & IPS_NAT_MASK) {
 841                 /* Need NAT */
 842                 ret = nat_callforwarding(skb, ct, ctinfo,
 843                                          protoff, data, dataoff,
 844                                          taddr, port, exp);
 845         } else {                /* Conntrack only */
 846                 if (nf_ct_expect_related(exp) == 0) {
 847                         pr_debug("nf_ct_q931: expect Call Forwarding ");
 848                         nf_ct_dump_tuple(&exp->tuple);
 849                 } else
 850                         ret = -1;
 851         }
 852
 853         nf_ct_expect_put(exp);
 854
 855         return ret;
 856 }
 857
 858 /****************************************************************************/
 859 static int process_setup(struct sk_buff *skb, struct nf_conn *ct,
 860                          enum ip_conntrack_info ctinfo,
 861                          unsigned int protoff,
 862                          unsigned char **data, int dataoff,
 863                          Setup_UUIE *setup)
 864 {
 865         int dir = CTINFO2DIR(ctinfo);
 866         int ret;
 867         int i;
 868         __be16 port;
 869         union nf_inet_addr addr;
 870         typeof(set_h225_addr_hook) set_h225_addr;
 871
 872         pr_debug("nf_ct_q931: Setup\n");
 873
 874         if (setup->options & eSetup_UUIE_h245Address) {
 875                 ret = expect_h245(skb, ct, ctinfo, protoff, data, dataoff,
 876                                   &setup->h245Address);
 877                 if (ret < 0)
 878                         return -1;
 879         }
 880
 881         set_h225_addr = rcu_dereference(set_h225_addr_hook);
 882         if ((setup->options & eSetup_UUIE_destCallSignalAddress) &&
 883             (set_h225_addr) && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 884             ct->status & IPS_NAT_MASK &&
 885             get_h225_addr(ct, *data, &setup->destCallSignalAddress,
 886                           &addr, &port) &&
 887             memcmp(&addr, &ct->tuplehash[!dir].tuple.src.u3, sizeof(addr))) {
 888                 pr_debug("nf_ct_q931: set destCallSignalAddress %pI6:%hu->%pI6:%hu\n",
 889                          &addr, ntohs(port), &ct->tuplehash[!dir].tuple.src.u3,
 890                          ntohs(ct->tuplehash[!dir].tuple.src.u.tcp.port));
 891                 ret = set_h225_addr(skb, protoff, data, dataoff,
 892                                     &setup->destCallSignalAddress,
 893                                     &ct->tuplehash[!dir].tuple.src.u3,
 894                                     ct->tuplehash[!dir].tuple.src.u.tcp.port);
 895                 if (ret < 0)
 896                         return -1;
 897         }
 898
 899         if ((setup->options & eSetup_UUIE_sourceCallSignalAddress) &&
 900             (set_h225_addr) && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
 901             ct->status & IPS_NAT_MASK &&
 902             get_h225_addr(ct, *data, &setup->sourceCallSignalAddress,
 903                           &addr, &port) &&
 904             memcmp(&addr, &ct->tuplehash[!dir].tuple.dst.u3, sizeof(addr))) {
 905                 pr_debug("nf_ct_q931: set sourceCallSignalAddress %pI6:%hu->%pI6:%hu\n",
 906                          &addr, ntohs(port), &ct->tuplehash[!dir].tuple.dst.u3,
 907                          ntohs(ct->tuplehash[!dir].tuple.dst.u.tcp.port));
 908                 ret = set_h225_addr(skb, protoff, data, dataoff,
 909                                     &setup->sourceCallSignalAddress,
 910                                     &ct->tuplehash[!dir].tuple.dst.u3,
 911                                     ct->tuplehash[!dir].tuple.dst.u.tcp.port);
 912                 if (ret < 0)
 913                         return -1;
 914         }
 915
 916         if (setup->options & eSetup_UUIE_fastStart) {
 917                 for (i = 0; i < setup->fastStart.count; i++) {
 918                         ret = process_olc(skb, ct, ctinfo,
 919                                           protoff, data, dataoff,
 920                                           &setup->fastStart.item[i]);
 921                         if (ret < 0)
 922                                 return -1;
 923                 }
 924         }
 925
 926         return 0;
 927 }
 928
 929 /****************************************************************************/
 930 static int process_callproceeding(struct sk_buff *skb,
 931                                   struct nf_conn *ct,
 932                                   enum ip_conntrack_info ctinfo,
 933                                   unsigned int protoff,
 934                                   unsigned char **data, int dataoff,
 935                                   CallProceeding_UUIE *callproc)
 936 {
 937         int ret;
 938         int i;
 939
 940         pr_debug("nf_ct_q931: CallProceeding\n");
 941
 942         if (callproc->options & eCallProceeding_UUIE_h245Address) {
 943                 ret = expect_h245(skb, ct, ctinfo, protoff, data, dataoff,
 944                                   &callproc->h245Address);
 945                 if (ret < 0)
 946                         return -1;
 947         }
 948
 949         if (callproc->options & eCallProceeding_UUIE_fastStart) {
 950                 for (i = 0; i < callproc->fastStart.count; i++) {
 951                         ret = process_olc(skb, ct, ctinfo,
 952                                           protoff, data, dataoff,
 953                                           &callproc->fastStart.item[i]);
 954                         if (ret < 0)
 955                                 return -1;
 956                 }
 957         }
 958
 959         return 0;
 960 }
 961
 962 /****************************************************************************/
 963 static int process_connect(struct sk_buff *skb, struct nf_conn *ct,
 964                            enum ip_conntrack_info ctinfo,
 965                            unsigned int protoff,
 966                            unsigned char **data, int dataoff,
 967                            Connect_UUIE *connect)
 968 {
 969         int ret;
 970         int i;
 971
 972         pr_debug("nf_ct_q931: Connect\n");
 973
 974         if (connect->options & eConnect_UUIE_h245Address) {
 975                 ret = expect_h245(skb, ct, ctinfo, protoff, data, dataoff,
 976                                   &connect->h245Address);
 977                 if (ret < 0)
 978                         return -1;
 979         }
 980
 981         if (connect->options & eConnect_UUIE_fastStart) {
 982                 for (i = 0; i < connect->fastStart.count; i++) {
 983                         ret = process_olc(skb, ct, ctinfo,
 984                                           protoff, data, dataoff,
 985                                           &connect->fastStart.item[i]);
 986                         if (ret < 0)
 987                                 return -1;
 988                 }
 989         }
 990
 991         return 0;
 992 }
 993
 994 /****************************************************************************/
 995 static int process_alerting(struct sk_buff *skb, struct nf_conn *ct,
 996                             enum ip_conntrack_info ctinfo,
 997                             unsigned int protoff,
 998                             unsigned char **data, int dataoff,
 999                             Alerting_UUIE *alert)
1000 {
1001         int ret;
1002         int i;
1003
1004         pr_debug("nf_ct_q931: Alerting\n");
1005
1006         if (alert->options & eAlerting_UUIE_h245Address) {
1007                 ret = expect_h245(skb, ct, ctinfo, protoff, data, dataoff,
1008                                   &alert->h245Address);
1009                 if (ret < 0)
1010                         return -1;
1011         }
1012
1013         if (alert->options & eAlerting_UUIE_fastStart) {
1014                 for (i = 0; i < alert->fastStart.count; i++) {
1015                         ret = process_olc(skb, ct, ctinfo,
1016                                           protoff, data, dataoff,
1017                                           &alert->fastStart.item[i]);
1018                         if (ret < 0)
1019                                 return -1;
1020                 }
1021         }
1022
1023         return 0;
1024 }
1025
1026 /****************************************************************************/
1027 static int process_facility(struct sk_buff *skb, struct nf_conn *ct,
1028                             enum ip_conntrack_info ctinfo,
1029                             unsigned int protoff,
1030                             unsigned char **data, int dataoff,
1031                             Facility_UUIE *facility)
1032 {
1033         int ret;
1034         int i;
1035
1036         pr_debug("nf_ct_q931: Facility\n");
1037
1038         if (facility->reason.choice == eFacilityReason_callForwarded) {
1039                 if (facility->options & eFacility_UUIE_alternativeAddress)
1040                         return expect_callforwarding(skb, ct, ctinfo,
1041                                                      protoff, data, dataoff,
1042                                                      &facility->
1043                                                      alternativeAddress);
1044                 return 0;
1045         }
1046
1047         if (facility->options & eFacility_UUIE_h245Address) {
1048                 ret = expect_h245(skb, ct, ctinfo, protoff, data, dataoff,
1049                                   &facility->h245Address);
1050                 if (ret < 0)
1051                         return -1;
1052         }
1053
1054         if (facility->options & eFacility_UUIE_fastStart) {
1055                 for (i = 0; i < facility->fastStart.count; i++) {
1056                         ret = process_olc(skb, ct, ctinfo,
1057                                           protoff, data, dataoff,
1058                                           &facility->fastStart.item[i]);
1059                         if (ret < 0)
1060                                 return -1;
1061                 }
1062         }
1063
1064         return 0;
1065 }
1066
1067 /****************************************************************************/
1068 static int process_progress(struct sk_buff *skb, struct nf_conn *ct,
1069                             enum ip_conntrack_info ctinfo,
1070                             unsigned int protoff,
1071                             unsigned char **data, int dataoff,
1072                             Progress_UUIE *progress)
1073 {
1074         int ret;
1075         int i;
1076
1077         pr_debug("nf_ct_q931: Progress\n");
1078
1079         if (progress->options & eProgress_UUIE_h245Address) {
1080                 ret = expect_h245(skb, ct, ctinfo, protoff, data, dataoff,
1081                                   &progress->h245Address);
1082                 if (ret < 0)
1083                         return -1;
1084         }
1085
1086         if (progress->options & eProgress_UUIE_fastStart) {
1087                 for (i = 0; i < progress->fastStart.count; i++) {
1088                         ret = process_olc(skb, ct, ctinfo,
1089                                           protoff, data, dataoff,
1090                                           &progress->fastStart.item[i]);
1091                         if (ret < 0)
1092                                 return -1;
1093                 }
1094         }
1095
1096         return 0;
1097 }
1098
1099 /****************************************************************************/
1100 static int process_q931(struct sk_buff *skb, struct nf_conn *ct,
1101                         enum ip_conntrack_info ctinfo,
1102                         unsigned int protoff, unsigned char **data, int dataoff,
1103                         Q931 *q931)
1104 {
1105         H323_UU_PDU *pdu = &q931->UUIE.h323_uu_pdu;
1106         int i;
1107         int ret = 0;
1108
1109         switch (pdu->h323_message_body.choice) {
1110         case eH323_UU_PDU_h323_message_body_setup:
1111                 ret = process_setup(skb, ct, ctinfo, protoff, data, dataoff,
1112                                     &pdu->h323_message_body.setup);
1113                 break;
1114         case eH323_UU_PDU_h323_message_body_callProceeding:
1115                 ret = process_callproceeding(skb, ct, ctinfo,
1116                                              protoff, data, dataoff,
1117                                              &pdu->h323_message_body.
1118                                              callProceeding);
1119                 break;
1120         case eH323_UU_PDU_h323_message_body_connect:
1121                 ret = process_connect(skb, ct, ctinfo, protoff, data, dataoff,
1122                                       &pdu->h323_message_body.connect);
1123                 break;
1124         case eH323_UU_PDU_h323_message_body_alerting:
1125                 ret = process_alerting(skb, ct, ctinfo, protoff, data, dataoff,
1126                                        &pdu->h323_message_body.alerting);
1127                 break;
1128         case eH323_UU_PDU_h323_message_body_facility:
1129                 ret = process_facility(skb, ct, ctinfo, protoff, data, dataoff,
1130                                        &pdu->h323_message_body.facility);
1131                 break;
1132         case eH323_UU_PDU_h323_message_body_progress:
1133                 ret = process_progress(skb, ct, ctinfo, protoff, data, dataoff,
1134                                        &pdu->h323_message_body.progress);
1135                 break;
1136         default:
1137                 pr_debug("nf_ct_q931: Q.931 signal %d\n",
1138                          pdu->h323_message_body.choice);
1139                 break;
1140         }
1141
1142         if (ret < 0)
1143                 return -1;
1144
1145         if (pdu->options & eH323_UU_PDU_h245Control) {
1146                 for (i = 0; i < pdu->h245Control.count; i++) {
1147                         ret = process_h245(skb, ct, ctinfo,
1148                                            protoff, data, dataoff,
1149                                            &pdu->h245Control.item[i]);
1150                         if (ret < 0)
1151                                 return -1;
1152                 }
1153         }
1154
1155         return 0;
1156 }
1157
1158 /****************************************************************************/
1159 static int q931_help(struct sk_buff *skb, unsigned int protoff,
1160                      struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1161 {
1162         static Q931 q931;
1163         unsigned char *data = NULL;
1164         int datalen;
1165         int dataoff;
1166         int ret;
1167
1168         /* Until there's been traffic both ways, don't look in packets. */
1169         if (ctinfo != IP_CT_ESTABLISHED && ctinfo != IP_CT_ESTABLISHED_REPLY)
1170                 return NF_ACCEPT;
1171
1172         pr_debug("nf_ct_q931: skblen = %u\n", skb->len);
1173
1174         spin_lock_bh(&nf_h323_lock);
1175
1176         /* Process each TPKT */
1177         while (get_tpkt_data(skb, protoff, ct, ctinfo,
1178                              &data, &datalen, &dataoff)) {
1179                 pr_debug("nf_ct_q931: TPKT len=%d ", datalen);
1180                 nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1181
1182                 /* Decode Q.931 signal */
1183                 ret = DecodeQ931(data, datalen, &q931);
1184                 if (ret < 0) {
1185                         pr_debug("nf_ct_q931: decoding error: %s\n",
1186                                  ret == H323_ERROR_BOUND ?
1187                                  "out of bound" : "out of range");
1188                         /* We don't drop when decoding error */
1189                         break;
1190                 }
1191
1192                 /* Process Q.931 signal */
1193                 if (process_q931(skb, ct, ctinfo, protoff,
1194                                  &data, dataoff, &q931) < 0)
1195                         goto drop;
1196         }
1197
1198         spin_unlock_bh(&nf_h323_lock);
1199         return NF_ACCEPT;
1200
1201       drop:
1202         spin_unlock_bh(&nf_h323_lock);
1203         nf_ct_helper_log(skb, ct, "cannot process Q.931 message");
1204         return NF_DROP;
1205 }
1206
1207 /****************************************************************************/
1208 static const struct nf_conntrack_expect_policy q931_exp_policy = {
1209         /* T.120 and H.245 */
1210         .max_expected           = H323_RTP_CHANNEL_MAX * 4 + 4,
1211         .timeout                = 240,
1212 };
1213
1214 static struct nf_conntrack_helper nf_conntrack_helper_q931[] __read_mostly = {
1215         {
1216                 .name                   = "Q.931",
1217                 .me                     = THIS_MODULE,
1218                 .data_len               = sizeof(struct nf_ct_h323_master),
1219                 .tuple.src.l3num        = AF_INET,
1220                 .tuple.src.u.tcp.port   = cpu_to_be16(Q931_PORT),
1221                 .tuple.dst.protonum     = IPPROTO_TCP,
1222                 .help                   = q931_help,
1223                 .expect_policy          = &q931_exp_policy,
1224         },
1225         {
1226                 .name                   = "Q.931",
1227                 .me                     = THIS_MODULE,
1228                 .tuple.src.l3num        = AF_INET6,
1229                 .tuple.src.u.tcp.port   = cpu_to_be16(Q931_PORT),
1230                 .tuple.dst.protonum     = IPPROTO_TCP,
1231                 .help                   = q931_help,
1232                 .expect_policy          = &q931_exp_policy,
1233         },
1234 };
1235
1236 /****************************************************************************/
1237 static unsigned char *get_udp_data(struct sk_buff *skb, unsigned int protoff,
1238                                    int *datalen)
1239 {
1240         const struct udphdr *uh;
1241         struct udphdr _uh;
1242         int dataoff;
1243
1244         uh = skb_header_pointer(skb, protoff, sizeof(_uh), &_uh);
1245         if (uh == NULL)
1246                 return NULL;
1247         dataoff = protoff + sizeof(_uh);
1248         if (dataoff >= skb->len)
1249                 return NULL;
1250         *datalen = skb->len - dataoff;
1251         return skb_header_pointer(skb, dataoff, *datalen, h323_buffer);
1252 }
1253
1254 /****************************************************************************/
1255 static struct nf_conntrack_expect *find_expect(struct nf_conn *ct,
1256                                                union nf_inet_addr *addr,
1257                                                __be16 port)
1258 {
1259         struct net *net = nf_ct_net(ct);
1260         struct nf_conntrack_expect *exp;
1261         struct nf_conntrack_tuple tuple;
1262
1263         memset(&tuple.src.u3, 0, sizeof(tuple.src.u3));
1264         tuple.src.u.tcp.port = 0;
1265         memcpy(&tuple.dst.u3, addr, sizeof(tuple.dst.u3));
1266         tuple.dst.u.tcp.port = port;
1267         tuple.dst.protonum = IPPROTO_TCP;
1268
1269         exp = __nf_ct_expect_find(net, nf_ct_zone(ct), &tuple);
1270         if (exp && exp->master == ct)
1271                 return exp;
1272         return NULL;
1273 }
1274
1275 /****************************************************************************/
1276 static int expect_q931(struct sk_buff *skb, struct nf_conn *ct,
1277                        enum ip_conntrack_info ctinfo,
1278                        unsigned int protoff, unsigned char **data,
1279                        TransportAddress *taddr, int count)
1280 {
1281         struct nf_ct_h323_master *info = nfct_help_data(ct);
1282         int dir = CTINFO2DIR(ctinfo);
1283         int ret = 0;
1284         int i;
1285         __be16 port;
1286         union nf_inet_addr addr;
1287         struct nf_conntrack_expect *exp;
1288         typeof(nat_q931_hook) nat_q931;
1289
1290         /* Look for the first related address */
1291         for (i = 0; i < count; i++) {
1292                 if (get_h225_addr(ct, *data, &taddr[i], &addr, &port) &&
1293                     memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3,
1294                            sizeof(addr)) == 0 && port != 0)
1295                         break;
1296         }
1297
1298         if (i >= count)         /* Not found */
1299                 return 0;
1300
1301         /* Create expect for Q.931 */
1302         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1303                 return -1;
1304         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1305                           gkrouted_only ? /* only accept calls from GK? */
1306                                 &ct->tuplehash[!dir].tuple.src.u3 : NULL,
1307                           &ct->tuplehash[!dir].tuple.dst.u3,
1308                           IPPROTO_TCP, NULL, &port);
1309         exp->helper = nf_conntrack_helper_q931;
1310         exp->flags = NF_CT_EXPECT_PERMANENT;    /* Accept multiple calls */
1311
1312         nat_q931 = rcu_dereference(nat_q931_hook);
1313         if (nat_q931 && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1314             ct->status & IPS_NAT_MASK) {        /* Need NAT */
1315                 ret = nat_q931(skb, ct, ctinfo, protoff, data,
1316                                taddr, i, port, exp);
1317         } else {                /* Conntrack only */
1318                 if (nf_ct_expect_related(exp) == 0) {
1319                         pr_debug("nf_ct_ras: expect Q.931 ");
1320                         nf_ct_dump_tuple(&exp->tuple);
1321
1322                         /* Save port for looking up expect in processing RCF */
1323                         info->sig_port[dir] = port;
1324                 } else
1325                         ret = -1;
1326         }
1327
1328         nf_ct_expect_put(exp);
1329
1330         return ret;
1331 }
1332
1333 /****************************************************************************/
1334 static int process_grq(struct sk_buff *skb, struct nf_conn *ct,
1335                        enum ip_conntrack_info ctinfo,
1336                        unsigned int protoff,
1337                        unsigned char **data, GatekeeperRequest *grq)
1338 {
1339         typeof(set_ras_addr_hook) set_ras_addr;
1340
1341         pr_debug("nf_ct_ras: GRQ\n");
1342
1343         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1344         if (set_ras_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1345             ct->status & IPS_NAT_MASK)  /* NATed */
1346                 return set_ras_addr(skb, ct, ctinfo, protoff, data,
1347                                     &grq->rasAddress, 1);
1348         return 0;
1349 }
1350
1351 /****************************************************************************/
1352 static int process_gcf(struct sk_buff *skb, struct nf_conn *ct,
1353                        enum ip_conntrack_info ctinfo,
1354                        unsigned int protoff,
1355                        unsigned char **data, GatekeeperConfirm *gcf)
1356 {
1357         int dir = CTINFO2DIR(ctinfo);
1358         int ret = 0;
1359         __be16 port;
1360         union nf_inet_addr addr;
1361         struct nf_conntrack_expect *exp;
1362
1363         pr_debug("nf_ct_ras: GCF\n");
1364
1365         if (!get_h225_addr(ct, *data, &gcf->rasAddress, &addr, &port))
1366                 return 0;
1367
1368         /* Registration port is the same as discovery port */
1369         if (!memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1370             port == ct->tuplehash[dir].tuple.src.u.udp.port)
1371                 return 0;
1372
1373         /* Avoid RAS expectation loops. A GCF is never expected. */
1374         if (test_bit(IPS_EXPECTED_BIT, &ct->status))
1375                 return 0;
1376
1377         /* Need new expect */
1378         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1379                 return -1;
1380         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1381                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1382                           IPPROTO_UDP, NULL, &port);
1383         exp->helper = nf_conntrack_helper_ras;
1384
1385         if (nf_ct_expect_related(exp) == 0) {
1386                 pr_debug("nf_ct_ras: expect RAS ");
1387                 nf_ct_dump_tuple(&exp->tuple);
1388         } else
1389                 ret = -1;
1390
1391         nf_ct_expect_put(exp);
1392
1393         return ret;
1394 }
1395
1396 /****************************************************************************/
1397 static int process_rrq(struct sk_buff *skb, struct nf_conn *ct,
1398                        enum ip_conntrack_info ctinfo,
1399                        unsigned int protoff,
1400                        unsigned char **data, RegistrationRequest *rrq)
1401 {
1402         struct nf_ct_h323_master *info = nfct_help_data(ct);
1403         int ret;
1404         typeof(set_ras_addr_hook) set_ras_addr;
1405
1406         pr_debug("nf_ct_ras: RRQ\n");
1407
1408         ret = expect_q931(skb, ct, ctinfo, protoff, data,
1409                           rrq->callSignalAddress.item,
1410                           rrq->callSignalAddress.count);
1411         if (ret < 0)
1412                 return -1;
1413
1414         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1415         if (set_ras_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1416             ct->status & IPS_NAT_MASK) {
1417                 ret = set_ras_addr(skb, ct, ctinfo, protoff, data,
1418                                    rrq->rasAddress.item,
1419                                    rrq->rasAddress.count);
1420                 if (ret < 0)
1421                         return -1;
1422         }
1423
1424         if (rrq->options & eRegistrationRequest_timeToLive) {
1425                 pr_debug("nf_ct_ras: RRQ TTL = %u seconds\n", rrq->timeToLive);
1426                 info->timeout = rrq->timeToLive;
1427         } else
1428                 info->timeout = default_rrq_ttl;
1429
1430         return 0;
1431 }
1432
1433 /****************************************************************************/
1434 static int process_rcf(struct sk_buff *skb, struct nf_conn *ct,
1435                        enum ip_conntrack_info ctinfo,
1436                        unsigned int protoff,
1437                        unsigned char **data, RegistrationConfirm *rcf)
1438 {
1439         struct nf_ct_h323_master *info = nfct_help_data(ct);
1440         int dir = CTINFO2DIR(ctinfo);
1441         int ret;
1442         struct nf_conntrack_expect *exp;
1443         typeof(set_sig_addr_hook) set_sig_addr;
1444
1445         pr_debug("nf_ct_ras: RCF\n");
1446
1447         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1448         if (set_sig_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1449             ct->status & IPS_NAT_MASK) {
1450                 ret = set_sig_addr(skb, ct, ctinfo, protoff, data,
1451                                         rcf->callSignalAddress.item,
1452                                         rcf->callSignalAddress.count);
1453                 if (ret < 0)
1454                         return -1;
1455         }
1456
1457         if (rcf->options & eRegistrationConfirm_timeToLive) {
1458                 pr_debug("nf_ct_ras: RCF TTL = %u seconds\n", rcf->timeToLive);
1459                 info->timeout = rcf->timeToLive;
1460         }
1461
1462         if (info->timeout > 0) {
1463                 pr_debug("nf_ct_ras: set RAS connection timeout to "
1464                          "%u seconds\n", info->timeout);
1465                 nf_ct_refresh(ct, skb, info->timeout * HZ);
1466
1467                 /* Set expect timeout */
1468                 spin_lock_bh(&nf_conntrack_expect_lock);
1469                 exp = find_expect(ct, &ct->tuplehash[dir].tuple.dst.u3,
1470                                   info->sig_port[!dir]);
1471                 if (exp) {
1472                         pr_debug("nf_ct_ras: set Q.931 expect "
1473                                  "timeout to %u seconds for",
1474                                  info->timeout);
1475                         nf_ct_dump_tuple(&exp->tuple);
1476                         mod_timer_pending(&exp->timeout,
1477                                           jiffies + info->timeout * HZ);
1478                 }
1479                 spin_unlock_bh(&nf_conntrack_expect_lock);
1480         }
1481
1482         return 0;
1483 }
1484
1485 /****************************************************************************/
1486 static int process_urq(struct sk_buff *skb, struct nf_conn *ct,
1487                        enum ip_conntrack_info ctinfo,
1488                        unsigned int protoff,
1489                        unsigned char **data, UnregistrationRequest *urq)
1490 {
1491         struct nf_ct_h323_master *info = nfct_help_data(ct);
1492         int dir = CTINFO2DIR(ctinfo);
1493         int ret;
1494         typeof(set_sig_addr_hook) set_sig_addr;
1495
1496         pr_debug("nf_ct_ras: URQ\n");
1497
1498         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1499         if (set_sig_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1500             ct->status & IPS_NAT_MASK) {
1501                 ret = set_sig_addr(skb, ct, ctinfo, protoff, data,
1502                                    urq->callSignalAddress.item,
1503                                    urq->callSignalAddress.count);
1504                 if (ret < 0)
1505                         return -1;
1506         }
1507
1508         /* Clear old expect */
1509         nf_ct_remove_expectations(ct);
1510         info->sig_port[dir] = 0;
1511         info->sig_port[!dir] = 0;
1512
1513         /* Give it 30 seconds for UCF or URJ */
1514         nf_ct_refresh(ct, skb, 30 * HZ);
1515
1516         return 0;
1517 }
1518
1519 /****************************************************************************/
1520 static int process_arq(struct sk_buff *skb, struct nf_conn *ct,
1521                        enum ip_conntrack_info ctinfo,
1522                        unsigned int protoff,
1523                        unsigned char **data, AdmissionRequest *arq)
1524 {
1525         const struct nf_ct_h323_master *info = nfct_help_data(ct);
1526         int dir = CTINFO2DIR(ctinfo);
1527         __be16 port;
1528         union nf_inet_addr addr;
1529         typeof(set_h225_addr_hook) set_h225_addr;
1530
1531         pr_debug("nf_ct_ras: ARQ\n");
1532
1533         set_h225_addr = rcu_dereference(set_h225_addr_hook);
1534         if ((arq->options & eAdmissionRequest_destCallSignalAddress) &&
1535             get_h225_addr(ct, *data, &arq->destCallSignalAddress,
1536                           &addr, &port) &&
1537             !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1538             port == info->sig_port[dir] &&
1539             nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1540             set_h225_addr && ct->status & IPS_NAT_MASK) {
1541                 /* Answering ARQ */
1542                 return set_h225_addr(skb, protoff, data, 0,
1543                                      &arq->destCallSignalAddress,
1544                                      &ct->tuplehash[!dir].tuple.dst.u3,
1545                                      info->sig_port[!dir]);
1546         }
1547
1548         if ((arq->options & eAdmissionRequest_srcCallSignalAddress) &&
1549             get_h225_addr(ct, *data, &arq->srcCallSignalAddress,
1550                           &addr, &port) &&
1551             !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1552             set_h225_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1553             ct->status & IPS_NAT_MASK) {
1554                 /* Calling ARQ */
1555                 return set_h225_addr(skb, protoff, data, 0,
1556                                      &arq->srcCallSignalAddress,
1557                                      &ct->tuplehash[!dir].tuple.dst.u3,
1558                                      port);
1559         }
1560
1561         return 0;
1562 }
1563
1564 /****************************************************************************/
1565 static int process_acf(struct sk_buff *skb, struct nf_conn *ct,
1566                        enum ip_conntrack_info ctinfo,
1567                        unsigned int protoff,
1568                        unsigned char **data, AdmissionConfirm *acf)
1569 {
1570         int dir = CTINFO2DIR(ctinfo);
1571         int ret = 0;
1572         __be16 port;
1573         union nf_inet_addr addr;
1574         struct nf_conntrack_expect *exp;
1575         typeof(set_sig_addr_hook) set_sig_addr;
1576
1577         pr_debug("nf_ct_ras: ACF\n");
1578
1579         if (!get_h225_addr(ct, *data, &acf->destCallSignalAddress,
1580                            &addr, &port))
1581                 return 0;
1582
1583         if (!memcmp(&addr, &ct->tuplehash[dir].tuple.dst.u3, sizeof(addr))) {
1584                 /* Answering ACF */
1585                 set_sig_addr = rcu_dereference(set_sig_addr_hook);
1586                 if (set_sig_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1587                     ct->status & IPS_NAT_MASK)
1588                         return set_sig_addr(skb, ct, ctinfo, protoff, data,
1589                                             &acf->destCallSignalAddress, 1);
1590                 return 0;
1591         }
1592
1593         /* Need new expect */
1594         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1595                 return -1;
1596         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1597                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1598                           IPPROTO_TCP, NULL, &port);
1599         exp->flags = NF_CT_EXPECT_PERMANENT;
1600         exp->helper = nf_conntrack_helper_q931;
1601
1602         if (nf_ct_expect_related(exp) == 0) {
1603                 pr_debug("nf_ct_ras: expect Q.931 ");
1604                 nf_ct_dump_tuple(&exp->tuple);
1605         } else
1606                 ret = -1;
1607
1608         nf_ct_expect_put(exp);
1609
1610         return ret;
1611 }
1612
1613 /****************************************************************************/
1614 static int process_lrq(struct sk_buff *skb, struct nf_conn *ct,
1615                        enum ip_conntrack_info ctinfo,
1616                        unsigned int protoff,
1617                        unsigned char **data, LocationRequest *lrq)
1618 {
1619         typeof(set_ras_addr_hook) set_ras_addr;
1620
1621         pr_debug("nf_ct_ras: LRQ\n");
1622
1623         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1624         if (set_ras_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1625             ct->status & IPS_NAT_MASK)
1626                 return set_ras_addr(skb, ct, ctinfo, protoff, data,
1627                                     &lrq->replyAddress, 1);
1628         return 0;
1629 }
1630
1631 /****************************************************************************/
1632 static int process_lcf(struct sk_buff *skb, struct nf_conn *ct,
1633                        enum ip_conntrack_info ctinfo,
1634                        unsigned int protoff,
1635                        unsigned char **data, LocationConfirm *lcf)
1636 {
1637         int dir = CTINFO2DIR(ctinfo);
1638         int ret = 0;
1639         __be16 port;
1640         union nf_inet_addr addr;
1641         struct nf_conntrack_expect *exp;
1642
1643         pr_debug("nf_ct_ras: LCF\n");
1644
1645         if (!get_h225_addr(ct, *data, &lcf->callSignalAddress,
1646                            &addr, &port))
1647                 return 0;
1648
1649         /* Need new expect for call signal */
1650         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1651                 return -1;
1652         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1653                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1654                           IPPROTO_TCP, NULL, &port);
1655         exp->flags = NF_CT_EXPECT_PERMANENT;
1656         exp->helper = nf_conntrack_helper_q931;
1657
1658         if (nf_ct_expect_related(exp) == 0) {
1659                 pr_debug("nf_ct_ras: expect Q.931 ");
1660                 nf_ct_dump_tuple(&exp->tuple);
1661         } else
1662                 ret = -1;
1663
1664         nf_ct_expect_put(exp);
1665
1666         /* Ignore rasAddress */
1667
1668         return ret;
1669 }
1670
1671 /****************************************************************************/
1672 static int process_irr(struct sk_buff *skb, struct nf_conn *ct,
1673                        enum ip_conntrack_info ctinfo,
1674                        unsigned int protoff,
1675                        unsigned char **data, InfoRequestResponse *irr)
1676 {
1677         int ret;
1678         typeof(set_ras_addr_hook) set_ras_addr;
1679         typeof(set_sig_addr_hook) set_sig_addr;
1680
1681         pr_debug("nf_ct_ras: IRR\n");
1682
1683         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1684         if (set_ras_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1685             ct->status & IPS_NAT_MASK) {
1686                 ret = set_ras_addr(skb, ct, ctinfo, protoff, data,
1687                                    &irr->rasAddress, 1);
1688                 if (ret < 0)
1689                         return -1;
1690         }
1691
1692         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1693         if (set_sig_addr && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
1694             ct->status & IPS_NAT_MASK) {
1695                 ret = set_sig_addr(skb, ct, ctinfo, protoff, data,
1696                                         irr->callSignalAddress.item,
1697                                         irr->callSignalAddress.count);
1698                 if (ret < 0)
1699                         return -1;
1700         }
1701
1702         return 0;
1703 }
1704
1705 /****************************************************************************/
1706 static int process_ras(struct sk_buff *skb, struct nf_conn *ct,
1707                        enum ip_conntrack_info ctinfo,
1708                        unsigned int protoff,
1709                        unsigned char **data, RasMessage *ras)
1710 {
1711         switch (ras->choice) {
1712         case eRasMessage_gatekeeperRequest:
1713                 return process_grq(skb, ct, ctinfo, protoff, data,
1714                                    &ras->gatekeeperRequest);
1715         case eRasMessage_gatekeeperConfirm:
1716                 return process_gcf(skb, ct, ctinfo, protoff, data,
1717                                    &ras->gatekeeperConfirm);
1718         case eRasMessage_registrationRequest:
1719                 return process_rrq(skb, ct, ctinfo, protoff, data,
1720                                    &ras->registrationRequest);
1721         case eRasMessage_registrationConfirm:
1722                 return process_rcf(skb, ct, ctinfo, protoff, data,
1723                                    &ras->registrationConfirm);
1724         case eRasMessage_unregistrationRequest:
1725                 return process_urq(skb, ct, ctinfo, protoff, data,
1726                                    &ras->unregistrationRequest);
1727         case eRasMessage_admissionRequest:
1728                 return process_arq(skb, ct, ctinfo, protoff, data,
1729                                    &ras->admissionRequest);
1730         case eRasMessage_admissionConfirm:
1731                 return process_acf(skb, ct, ctinfo, protoff, data,
1732                                    &ras->admissionConfirm);
1733         case eRasMessage_locationRequest:
1734                 return process_lrq(skb, ct, ctinfo, protoff, data,
1735                                    &ras->locationRequest);
1736         case eRasMessage_locationConfirm:
1737                 return process_lcf(skb, ct, ctinfo, protoff, data,
1738                                    &ras->locationConfirm);
1739         case eRasMessage_infoRequestResponse:
1740                 return process_irr(skb, ct, ctinfo, protoff, data,
1741                                    &ras->infoRequestResponse);
1742         default:
1743                 pr_debug("nf_ct_ras: RAS message %d\n", ras->choice);
1744                 break;
1745         }
1746
1747         return 0;
1748 }
1749
1750 /****************************************************************************/
1751 static int ras_help(struct sk_buff *skb, unsigned int protoff,
1752                     struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1753 {
1754         static RasMessage ras;
1755         unsigned char *data;
1756         int datalen = 0;
1757         int ret;
1758
1759         pr_debug("nf_ct_ras: skblen = %u\n", skb->len);
1760
1761         spin_lock_bh(&nf_h323_lock);
1762
1763         /* Get UDP data */
1764         data = get_udp_data(skb, protoff, &datalen);
1765         if (data == NULL)
1766                 goto accept;
1767         pr_debug("nf_ct_ras: RAS message len=%d ", datalen);
1768         nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1769
1770         /* Decode RAS message */
1771         ret = DecodeRasMessage(data, datalen, &ras);
1772         if (ret < 0) {
1773                 pr_debug("nf_ct_ras: decoding error: %s\n",
1774                          ret == H323_ERROR_BOUND ?
1775                          "out of bound" : "out of range");
1776                 goto accept;
1777         }
1778
1779         /* Process RAS message */
1780         if (process_ras(skb, ct, ctinfo, protoff, &data, &ras) < 0)
1781                 goto drop;
1782
1783       accept:
1784         spin_unlock_bh(&nf_h323_lock);
1785         return NF_ACCEPT;
1786
1787       drop:
1788         spin_unlock_bh(&nf_h323_lock);
1789         nf_ct_helper_log(skb, ct, "cannot process RAS message");
1790         return NF_DROP;
1791 }
1792
1793 /****************************************************************************/
1794 static const struct nf_conntrack_expect_policy ras_exp_policy = {
1795         .max_expected           = 32,
1796         .timeout                = 240,
1797 };
1798
1799 static struct nf_conntrack_helper nf_conntrack_helper_ras[] __read_mostly = {
1800         {
1801                 .name                   = "RAS",
1802                 .me                     = THIS_MODULE,
1803                 .data_len               = sizeof(struct nf_ct_h323_master),
1804                 .tuple.src.l3num        = AF_INET,
1805                 .tuple.src.u.udp.port   = cpu_to_be16(RAS_PORT),
1806                 .tuple.dst.protonum     = IPPROTO_UDP,
1807                 .help                   = ras_help,
1808                 .expect_policy          = &ras_exp_policy,
1809         },
1810         {
1811                 .name                   = "RAS",
1812                 .me                     = THIS_MODULE,
1813                 .data_len               = sizeof(struct nf_ct_h323_master),
1814                 .tuple.src.l3num        = AF_INET6,
1815                 .tuple.src.u.udp.port   = cpu_to_be16(RAS_PORT),
1816                 .tuple.dst.protonum     = IPPROTO_UDP,
1817                 .help                   = ras_help,
1818                 .expect_policy          = &ras_exp_policy,
1819         },
1820 };
1821
1822 /****************************************************************************/
1823 static void __exit nf_conntrack_h323_fini(void)
1824 {
1825         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[1]);
1826         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1827         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1828         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1829         nf_conntrack_helper_unregister(&nf_conntrack_helper_h245);
1830         kfree(h323_buffer);
1831         pr_debug("nf_ct_h323: fini\n");
1832 }
1833
1834 /****************************************************************************/
1835 static int __init nf_conntrack_h323_init(void)
1836 {
1837         int ret;
1838
1839         h323_buffer = kmalloc(65536, GFP_KERNEL);
1840         if (!h323_buffer)
1841                 return -ENOMEM;
1842         ret = nf_conntrack_helper_register(&nf_conntrack_helper_h245);
1843         if (ret < 0)
1844                 goto err1;
1845         ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[0]);
1846         if (ret < 0)
1847                 goto err2;
1848         ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[1]);
1849         if (ret < 0)
1850                 goto err3;
1851         ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[0]);
1852         if (ret < 0)
1853                 goto err4;
1854         ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[1]);
1855         if (ret < 0)
1856                 goto err5;
1857         pr_debug("nf_ct_h323: init success\n");
1858         return 0;
1859
1860 err5:
1861         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1862 err4:
1863         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1864 err3:
1865         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1866 err2:
1867         nf_conntrack_helper_unregister(&nf_conntrack_helper_h245);
1868 err1:
1869         kfree(h323_buffer);
1870         return ret;
1871 }
1872
1873 /****************************************************************************/
1874 module_init(nf_conntrack_h323_init);
1875 module_exit(nf_conntrack_h323_fini);
1876
1877 EXPORT_SYMBOL_GPL(get_h225_addr);
1878 EXPORT_SYMBOL_GPL(set_h245_addr_hook);
1879 EXPORT_SYMBOL_GPL(set_h225_addr_hook);
1880 EXPORT_SYMBOL_GPL(set_sig_addr_hook);
1881 EXPORT_SYMBOL_GPL(set_ras_addr_hook);
1882 EXPORT_SYMBOL_GPL(nat_rtp_rtcp_hook);
1883 EXPORT_SYMBOL_GPL(nat_t120_hook);
1884 EXPORT_SYMBOL_GPL(nat_h245_hook);
1885 EXPORT_SYMBOL_GPL(nat_callforwarding_hook);
1886 EXPORT_SYMBOL_GPL(nat_q931_hook);
1887
1888 MODULE_AUTHOR("Jing Min Zhao <zhaojingmin@users.sourceforge.net>");
1889 MODULE_DESCRIPTION("H.323 connection tracking helper");
1890 MODULE_LICENSE("GPL");
1891 MODULE_ALIAS("ip_conntrack_h323");
1892 MODULE_ALIAS_NFCT_HELPER("RAS");
1893 MODULE_ALIAS_NFCT_HELPER("Q.931");
1894 MODULE_ALIAS_NFCT_HELPER("H.245");