linux/net/netfilter/nf_conntrack_h323_main.c
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   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/udp.h>
  21#include <linux/tcp.h>
  22#include <linux/skbuff.h>
  23#include <net/route.h>
  24#include <net/ip6_route.h>
  25
  26#include <net/netfilter/nf_conntrack.h>
  27#include <net/netfilter/nf_conntrack_core.h>
  28#include <net/netfilter/nf_conntrack_tuple.h>
  29#include <net/netfilter/nf_conntrack_expect.h>
  30#include <net/netfilter/nf_conntrack_ecache.h>
  31#include <net/netfilter/nf_conntrack_helper.h>
  32#include <linux/netfilter/nf_conntrack_h323.h>
  33
  34/* Parameters */
  35static unsigned int default_rrq_ttl __read_mostly = 300;
  36module_param(default_rrq_ttl, uint, 0600);
  37MODULE_PARM_DESC(default_rrq_ttl, "use this TTL if it's missing in RRQ");
  38
  39static int gkrouted_only __read_mostly = 1;
  40module_param(gkrouted_only, int, 0600);
  41MODULE_PARM_DESC(gkrouted_only, "only accept calls from gatekeeper");
  42
  43static int callforward_filter __read_mostly = 1;
  44module_param(callforward_filter, bool, 0600);
  45MODULE_PARM_DESC(callforward_filter, "only create call forwarding expectations "
  46                                     "if both endpoints are on different sides "
  47                                     "(determined by routing information)");
  48
  49/* Hooks for NAT */
  50int (*set_h245_addr_hook) (struct sk_buff *skb,
  51                           unsigned char **data, int dataoff,
  52                           H245_TransportAddress *taddr,
  53                           union nf_inet_addr *addr, __be16 port)
  54                           __read_mostly;
  55int (*set_h225_addr_hook) (struct sk_buff *skb,
  56                           unsigned char **data, int dataoff,
  57                           TransportAddress *taddr,
  58                           union nf_inet_addr *addr, __be16 port)
  59                           __read_mostly;
  60int (*set_sig_addr_hook) (struct sk_buff *skb,
  61                          struct nf_conn *ct,
  62                          enum ip_conntrack_info ctinfo,
  63                          unsigned char **data,
  64                          TransportAddress *taddr, int count) __read_mostly;
  65int (*set_ras_addr_hook) (struct sk_buff *skb,
  66                          struct nf_conn *ct,
  67                          enum ip_conntrack_info ctinfo,
  68                          unsigned char **data,
  69                          TransportAddress *taddr, int count) __read_mostly;
  70int (*nat_rtp_rtcp_hook) (struct sk_buff *skb,
  71                          struct nf_conn *ct,
  72                          enum ip_conntrack_info ctinfo,
  73                          unsigned char **data, int dataoff,
  74                          H245_TransportAddress *taddr,
  75                          __be16 port, __be16 rtp_port,
  76                          struct nf_conntrack_expect *rtp_exp,
  77                          struct nf_conntrack_expect *rtcp_exp) __read_mostly;
  78int (*nat_t120_hook) (struct sk_buff *skb,
  79                      struct nf_conn *ct,
  80                      enum ip_conntrack_info ctinfo,
  81                      unsigned char **data, int dataoff,
  82                      H245_TransportAddress *taddr, __be16 port,
  83                      struct nf_conntrack_expect *exp) __read_mostly;
  84int (*nat_h245_hook) (struct sk_buff *skb,
  85                      struct nf_conn *ct,
  86                      enum ip_conntrack_info ctinfo,
  87                      unsigned char **data, int dataoff,
  88                      TransportAddress *taddr, __be16 port,
  89                      struct nf_conntrack_expect *exp) __read_mostly;
  90int (*nat_callforwarding_hook) (struct sk_buff *skb,
  91                                struct nf_conn *ct,
  92                                enum ip_conntrack_info ctinfo,
  93                                unsigned char **data, int dataoff,
  94                                TransportAddress *taddr, __be16 port,
  95                                struct nf_conntrack_expect *exp) __read_mostly;
  96int (*nat_q931_hook) (struct sk_buff *skb,
  97                      struct nf_conn *ct,
  98                      enum ip_conntrack_info ctinfo,
  99                      unsigned char **data, TransportAddress *taddr, int idx,
 100                      __be16 port, struct nf_conntrack_expect *exp)
 101                      __read_mostly;
 102
 103static DEFINE_SPINLOCK(nf_h323_lock);
 104static char *h323_buffer;
 105
 106static struct nf_conntrack_helper nf_conntrack_helper_h245;
 107static struct nf_conntrack_helper nf_conntrack_helper_q931[];
 108static struct nf_conntrack_helper nf_conntrack_helper_ras[];
 109
 110/****************************************************************************/
 111static int get_tpkt_data(struct sk_buff *skb, unsigned int protoff,
 112                         struct nf_conn *ct, enum ip_conntrack_info ctinfo,
 113                         unsigned char **data, int *datalen, int *dataoff)
 114{
 115        struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
 116        int dir = CTINFO2DIR(ctinfo);
 117        const struct tcphdr *th;
 118        struct tcphdr _tcph;
 119        int tcpdatalen;
 120        int tcpdataoff;
 121        unsigned char *tpkt;
 122        int tpktlen;
 123        int tpktoff;
 124
 125        /* Get TCP header */
 126        th = skb_header_pointer(skb, protoff, sizeof(_tcph), &_tcph);
 127        if (th == NULL)
 128                return 0;
 129
 130        /* Get TCP data offset */
 131        tcpdataoff = protoff + th->doff * 4;
 132
 133        /* Get TCP data length */
 134        tcpdatalen = skb->len - tcpdataoff;
 135        if (tcpdatalen <= 0)    /* No TCP data */
 136                goto clear_out;
 137
 138        if (*data == NULL) {    /* first TPKT */
 139                /* Get first TPKT pointer */
 140                tpkt = skb_header_pointer(skb, tcpdataoff, tcpdatalen,
 141                                          h323_buffer);
 142                BUG_ON(tpkt == NULL);
 143
 144                /* Validate TPKT identifier */
 145                if (tcpdatalen < 4 || tpkt[0] != 0x03 || tpkt[1] != 0) {
 146                        /* Netmeeting sends TPKT header and data separately */
 147                        if (info->tpkt_len[dir] > 0) {
 148                                pr_debug("nf_ct_h323: previous packet "
 149                                         "indicated separate TPKT data of %hu "
 150                                         "bytes\n", info->tpkt_len[dir]);
 151                                if (info->tpkt_len[dir] <= tcpdatalen) {
 152                                        /* Yes, there was a TPKT header
 153                                         * received */
 154                                        *data = tpkt;
 155                                        *datalen = info->tpkt_len[dir];
 156                                        *dataoff = 0;
 157                                        goto out;
 158                                }
 159
 160                                /* Fragmented TPKT */
 161                                pr_debug("nf_ct_h323: fragmented TPKT\n");
 162                                goto clear_out;
 163                        }
 164
 165                        /* It is not even a TPKT */
 166                        return 0;
 167                }
 168                tpktoff = 0;
 169        } else {                /* Next TPKT */
 170                tpktoff = *dataoff + *datalen;
 171                tcpdatalen -= tpktoff;
 172                if (tcpdatalen <= 4)    /* No more TPKT */
 173                        goto clear_out;
 174                tpkt = *data + *datalen;
 175
 176                /* Validate TPKT identifier */
 177                if (tpkt[0] != 0x03 || tpkt[1] != 0)
 178                        goto clear_out;
 179        }
 180
 181        /* Validate TPKT length */
 182        tpktlen = tpkt[2] * 256 + tpkt[3];
 183        if (tpktlen < 4)
 184                goto clear_out;
 185        if (tpktlen > tcpdatalen) {
 186                if (tcpdatalen == 4) {  /* Separate TPKT header */
 187                        /* Netmeeting sends TPKT header and data separately */
 188                        pr_debug("nf_ct_h323: separate TPKT header indicates "
 189                                 "there will be TPKT data of %hu bytes\n",
 190                                 tpktlen - 4);
 191                        info->tpkt_len[dir] = tpktlen - 4;
 192                        return 0;
 193                }
 194
 195                if (net_ratelimit())
 196                        printk("nf_ct_h323: incomplete TPKT (fragmented?)\n");
 197                goto clear_out;
 198        }
 199
 200        /* This is the encapsulated data */
 201        *data = tpkt + 4;
 202        *datalen = tpktlen - 4;
 203        *dataoff = tpktoff + 4;
 204
 205      out:
 206        /* Clear TPKT length */
 207        info->tpkt_len[dir] = 0;
 208        return 1;
 209
 210      clear_out:
 211        info->tpkt_len[dir] = 0;
 212        return 0;
 213}
 214
 215/****************************************************************************/
 216static int get_h245_addr(struct nf_conn *ct, const unsigned char *data,
 217                         H245_TransportAddress *taddr,
 218                         union nf_inet_addr *addr, __be16 *port)
 219{
 220        const unsigned char *p;
 221        int len;
 222
 223        if (taddr->choice != eH245_TransportAddress_unicastAddress)
 224                return 0;
 225
 226        switch (taddr->unicastAddress.choice) {
 227        case eUnicastAddress_iPAddress:
 228                if (nf_ct_l3num(ct) != AF_INET)
 229                        return 0;
 230                p = data + taddr->unicastAddress.iPAddress.network;
 231                len = 4;
 232                break;
 233        case eUnicastAddress_iP6Address:
 234                if (nf_ct_l3num(ct) != AF_INET6)
 235                        return 0;
 236                p = data + taddr->unicastAddress.iP6Address.network;
 237                len = 16;
 238                break;
 239        default:
 240                return 0;
 241        }
 242
 243        memcpy(addr, p, len);
 244        memset((void *)addr + len, 0, sizeof(*addr) - len);
 245        memcpy(port, p + len, sizeof(__be16));
 246
 247        return 1;
 248}
 249
 250/****************************************************************************/
 251static int expect_rtp_rtcp(struct sk_buff *skb, struct nf_conn *ct,
 252                           enum ip_conntrack_info ctinfo,
 253                           unsigned char **data, int dataoff,
 254                           H245_TransportAddress *taddr)
 255{
 256        int dir = CTINFO2DIR(ctinfo);
 257        int ret = 0;
 258        __be16 port;
 259        __be16 rtp_port, rtcp_port;
 260        union nf_inet_addr addr;
 261        struct nf_conntrack_expect *rtp_exp;
 262        struct nf_conntrack_expect *rtcp_exp;
 263        typeof(nat_rtp_rtcp_hook) nat_rtp_rtcp;
 264
 265        /* Read RTP or RTCP address */
 266        if (!get_h245_addr(ct, *data, taddr, &addr, &port) ||
 267            memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
 268            port == 0)
 269                return 0;
 270
 271        /* RTP port is even */
 272        port &= htons(~1);
 273        rtp_port = port;
 274        rtcp_port = htons(ntohs(port) + 1);
 275
 276        /* Create expect for RTP */
 277        if ((rtp_exp = nf_ct_expect_alloc(ct)) == NULL)
 278                return -1;
 279        nf_ct_expect_init(rtp_exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 280                          &ct->tuplehash[!dir].tuple.src.u3,
 281                          &ct->tuplehash[!dir].tuple.dst.u3,
 282                          IPPROTO_UDP, NULL, &rtp_port);
 283
 284        /* Create expect for RTCP */
 285        if ((rtcp_exp = nf_ct_expect_alloc(ct)) == NULL) {
 286                nf_ct_expect_put(rtp_exp);
 287                return -1;
 288        }
 289        nf_ct_expect_init(rtcp_exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 290                          &ct->tuplehash[!dir].tuple.src.u3,
 291                          &ct->tuplehash[!dir].tuple.dst.u3,
 292                          IPPROTO_UDP, NULL, &rtcp_port);
 293
 294        if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 295                   &ct->tuplehash[!dir].tuple.dst.u3,
 296                   sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 297                   (nat_rtp_rtcp = rcu_dereference(nat_rtp_rtcp_hook)) &&
 298                   ct->status & IPS_NAT_MASK) {
 299                /* NAT needed */
 300                ret = nat_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
 301                                   taddr, port, rtp_port, rtp_exp, rtcp_exp);
 302        } else {                /* Conntrack only */
 303                if (nf_ct_expect_related(rtp_exp) == 0) {
 304                        if (nf_ct_expect_related(rtcp_exp) == 0) {
 305                                pr_debug("nf_ct_h323: expect RTP ");
 306                                nf_ct_dump_tuple(&rtp_exp->tuple);
 307                                pr_debug("nf_ct_h323: expect RTCP ");
 308                                nf_ct_dump_tuple(&rtcp_exp->tuple);
 309                        } else {
 310                                nf_ct_unexpect_related(rtp_exp);
 311                                ret = -1;
 312                        }
 313                } else
 314                        ret = -1;
 315        }
 316
 317        nf_ct_expect_put(rtp_exp);
 318        nf_ct_expect_put(rtcp_exp);
 319
 320        return ret;
 321}
 322
 323/****************************************************************************/
 324static int expect_t120(struct sk_buff *skb,
 325                       struct nf_conn *ct,
 326                       enum ip_conntrack_info ctinfo,
 327                       unsigned char **data, int dataoff,
 328                       H245_TransportAddress *taddr)
 329{
 330        int dir = CTINFO2DIR(ctinfo);
 331        int ret = 0;
 332        __be16 port;
 333        union nf_inet_addr addr;
 334        struct nf_conntrack_expect *exp;
 335        typeof(nat_t120_hook) nat_t120;
 336
 337        /* Read T.120 address */
 338        if (!get_h245_addr(ct, *data, taddr, &addr, &port) ||
 339            memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
 340            port == 0)
 341                return 0;
 342
 343        /* Create expect for T.120 connections */
 344        if ((exp = nf_ct_expect_alloc(ct)) == NULL)
 345                return -1;
 346        nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 347                          &ct->tuplehash[!dir].tuple.src.u3,
 348                          &ct->tuplehash[!dir].tuple.dst.u3,
 349                          IPPROTO_TCP, NULL, &port);
 350        exp->flags = NF_CT_EXPECT_PERMANENT;    /* Accept multiple channels */
 351
 352        if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 353                   &ct->tuplehash[!dir].tuple.dst.u3,
 354                   sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 355            (nat_t120 = rcu_dereference(nat_t120_hook)) &&
 356            ct->status & IPS_NAT_MASK) {
 357                /* NAT needed */
 358                ret = nat_t120(skb, ct, ctinfo, data, dataoff, taddr,
 359                               port, exp);
 360        } else {                /* Conntrack only */
 361                if (nf_ct_expect_related(exp) == 0) {
 362                        pr_debug("nf_ct_h323: expect T.120 ");
 363                        nf_ct_dump_tuple(&exp->tuple);
 364                } else
 365                        ret = -1;
 366        }
 367
 368        nf_ct_expect_put(exp);
 369
 370        return ret;
 371}
 372
 373/****************************************************************************/
 374static int process_h245_channel(struct sk_buff *skb,
 375                                struct nf_conn *ct,
 376                                enum ip_conntrack_info ctinfo,
 377                                unsigned char **data, int dataoff,
 378                                H2250LogicalChannelParameters *channel)
 379{
 380        int ret;
 381
 382        if (channel->options & eH2250LogicalChannelParameters_mediaChannel) {
 383                /* RTP */
 384                ret = expect_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
 385                                      &channel->mediaChannel);
 386                if (ret < 0)
 387                        return -1;
 388        }
 389
 390        if (channel->
 391            options & eH2250LogicalChannelParameters_mediaControlChannel) {
 392                /* RTCP */
 393                ret = expect_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
 394                                      &channel->mediaControlChannel);
 395                if (ret < 0)
 396                        return -1;
 397        }
 398
 399        return 0;
 400}
 401
 402/****************************************************************************/
 403static int process_olc(struct sk_buff *skb, struct nf_conn *ct,
 404                       enum ip_conntrack_info ctinfo,
 405                       unsigned char **data, int dataoff,
 406                       OpenLogicalChannel *olc)
 407{
 408        int ret;
 409
 410        pr_debug("nf_ct_h323: OpenLogicalChannel\n");
 411
 412        if (olc->forwardLogicalChannelParameters.multiplexParameters.choice ==
 413            eOpenLogicalChannel_forwardLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters)
 414        {
 415                ret = process_h245_channel(skb, ct, ctinfo, data, dataoff,
 416                                           &olc->
 417                                           forwardLogicalChannelParameters.
 418                                           multiplexParameters.
 419                                           h2250LogicalChannelParameters);
 420                if (ret < 0)
 421                        return -1;
 422        }
 423
 424        if ((olc->options &
 425             eOpenLogicalChannel_reverseLogicalChannelParameters) &&
 426            (olc->reverseLogicalChannelParameters.options &
 427             eOpenLogicalChannel_reverseLogicalChannelParameters_multiplexParameters)
 428            && (olc->reverseLogicalChannelParameters.multiplexParameters.
 429                choice ==
 430                eOpenLogicalChannel_reverseLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters))
 431        {
 432                ret =
 433                    process_h245_channel(skb, ct, ctinfo, data, dataoff,
 434                                         &olc->
 435                                         reverseLogicalChannelParameters.
 436                                         multiplexParameters.
 437                                         h2250LogicalChannelParameters);
 438                if (ret < 0)
 439                        return -1;
 440        }
 441
 442        if ((olc->options & eOpenLogicalChannel_separateStack) &&
 443            olc->forwardLogicalChannelParameters.dataType.choice ==
 444            eDataType_data &&
 445            olc->forwardLogicalChannelParameters.dataType.data.application.
 446            choice == eDataApplicationCapability_application_t120 &&
 447            olc->forwardLogicalChannelParameters.dataType.data.application.
 448            t120.choice == eDataProtocolCapability_separateLANStack &&
 449            olc->separateStack.networkAddress.choice ==
 450            eNetworkAccessParameters_networkAddress_localAreaAddress) {
 451                ret = expect_t120(skb, ct, ctinfo, data, dataoff,
 452                                  &olc->separateStack.networkAddress.
 453                                  localAreaAddress);
 454                if (ret < 0)
 455                        return -1;
 456        }
 457
 458        return 0;
 459}
 460
 461/****************************************************************************/
 462static int process_olca(struct sk_buff *skb, struct nf_conn *ct,
 463                        enum ip_conntrack_info ctinfo,
 464                        unsigned char **data, int dataoff,
 465                        OpenLogicalChannelAck *olca)
 466{
 467        H2250LogicalChannelAckParameters *ack;
 468        int ret;
 469
 470        pr_debug("nf_ct_h323: OpenLogicalChannelAck\n");
 471
 472        if ((olca->options &
 473             eOpenLogicalChannelAck_reverseLogicalChannelParameters) &&
 474            (olca->reverseLogicalChannelParameters.options &
 475             eOpenLogicalChannelAck_reverseLogicalChannelParameters_multiplexParameters)
 476            && (olca->reverseLogicalChannelParameters.multiplexParameters.
 477                choice ==
 478                eOpenLogicalChannelAck_reverseLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters))
 479        {
 480                ret = process_h245_channel(skb, ct, ctinfo, data, dataoff,
 481                                           &olca->
 482                                           reverseLogicalChannelParameters.
 483                                           multiplexParameters.
 484                                           h2250LogicalChannelParameters);
 485                if (ret < 0)
 486                        return -1;
 487        }
 488
 489        if ((olca->options &
 490             eOpenLogicalChannelAck_forwardMultiplexAckParameters) &&
 491            (olca->forwardMultiplexAckParameters.choice ==
 492             eOpenLogicalChannelAck_forwardMultiplexAckParameters_h2250LogicalChannelAckParameters))
 493        {
 494                ack = &olca->forwardMultiplexAckParameters.
 495                    h2250LogicalChannelAckParameters;
 496                if (ack->options &
 497                    eH2250LogicalChannelAckParameters_mediaChannel) {
 498                        /* RTP */
 499                        ret = expect_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
 500                                              &ack->mediaChannel);
 501                        if (ret < 0)
 502                                return -1;
 503                }
 504
 505                if (ack->options &
 506                    eH2250LogicalChannelAckParameters_mediaControlChannel) {
 507                        /* RTCP */
 508                        ret = expect_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
 509                                              &ack->mediaControlChannel);
 510                        if (ret < 0)
 511                                return -1;
 512                }
 513        }
 514
 515        if ((olca->options & eOpenLogicalChannelAck_separateStack) &&
 516                olca->separateStack.networkAddress.choice ==
 517                eNetworkAccessParameters_networkAddress_localAreaAddress) {
 518                ret = expect_t120(skb, ct, ctinfo, data, dataoff,
 519                                  &olca->separateStack.networkAddress.
 520                                  localAreaAddress);
 521                if (ret < 0)
 522                        return -1;
 523        }
 524
 525        return 0;
 526}
 527
 528/****************************************************************************/
 529static int process_h245(struct sk_buff *skb, struct nf_conn *ct,
 530                        enum ip_conntrack_info ctinfo,
 531                        unsigned char **data, int dataoff,
 532                        MultimediaSystemControlMessage *mscm)
 533{
 534        switch (mscm->choice) {
 535        case eMultimediaSystemControlMessage_request:
 536                if (mscm->request.choice ==
 537                    eRequestMessage_openLogicalChannel) {
 538                        return process_olc(skb, ct, ctinfo, data, dataoff,
 539                                           &mscm->request.openLogicalChannel);
 540                }
 541                pr_debug("nf_ct_h323: H.245 Request %d\n",
 542                         mscm->request.choice);
 543                break;
 544        case eMultimediaSystemControlMessage_response:
 545                if (mscm->response.choice ==
 546                    eResponseMessage_openLogicalChannelAck) {
 547                        return process_olca(skb, ct, ctinfo, data, dataoff,
 548                                            &mscm->response.
 549                                            openLogicalChannelAck);
 550                }
 551                pr_debug("nf_ct_h323: H.245 Response %d\n",
 552                         mscm->response.choice);
 553                break;
 554        default:
 555                pr_debug("nf_ct_h323: H.245 signal %d\n", mscm->choice);
 556                break;
 557        }
 558
 559        return 0;
 560}
 561
 562/****************************************************************************/
 563static int h245_help(struct sk_buff *skb, unsigned int protoff,
 564                     struct nf_conn *ct, enum ip_conntrack_info ctinfo)
 565{
 566        static MultimediaSystemControlMessage mscm;
 567        unsigned char *data = NULL;
 568        int datalen;
 569        int dataoff;
 570        int ret;
 571
 572        /* Until there's been traffic both ways, don't look in packets. */
 573        if (ctinfo != IP_CT_ESTABLISHED &&
 574            ctinfo != IP_CT_ESTABLISHED + IP_CT_IS_REPLY) {
 575                return NF_ACCEPT;
 576        }
 577        pr_debug("nf_ct_h245: skblen = %u\n", skb->len);
 578
 579        spin_lock_bh(&nf_h323_lock);
 580
 581        /* Process each TPKT */
 582        while (get_tpkt_data(skb, protoff, ct, ctinfo,
 583                             &data, &datalen, &dataoff)) {
 584                pr_debug("nf_ct_h245: TPKT len=%d ", datalen);
 585                nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
 586
 587                /* Decode H.245 signal */
 588                ret = DecodeMultimediaSystemControlMessage(data, datalen,
 589                                                           &mscm);
 590                if (ret < 0) {
 591                        pr_debug("nf_ct_h245: decoding error: %s\n",
 592                                 ret == H323_ERROR_BOUND ?
 593                                 "out of bound" : "out of range");
 594                        /* We don't drop when decoding error */
 595                        break;
 596                }
 597
 598                /* Process H.245 signal */
 599                if (process_h245(skb, ct, ctinfo, &data, dataoff, &mscm) < 0)
 600                        goto drop;
 601        }
 602
 603        spin_unlock_bh(&nf_h323_lock);
 604        return NF_ACCEPT;
 605
 606      drop:
 607        spin_unlock_bh(&nf_h323_lock);
 608        if (net_ratelimit())
 609                printk("nf_ct_h245: packet dropped\n");
 610        return NF_DROP;
 611}
 612
 613/****************************************************************************/
 614static const struct nf_conntrack_expect_policy h245_exp_policy = {
 615        .max_expected   = H323_RTP_CHANNEL_MAX * 4 + 2 /* T.120 */,
 616        .timeout        = 240,
 617};
 618
 619static struct nf_conntrack_helper nf_conntrack_helper_h245 __read_mostly = {
 620        .name                   = "H.245",
 621        .me                     = THIS_MODULE,
 622        .tuple.src.l3num        = AF_UNSPEC,
 623        .tuple.dst.protonum     = IPPROTO_UDP,
 624        .help                   = h245_help,
 625        .expect_policy          = &h245_exp_policy,
 626};
 627
 628/****************************************************************************/
 629int get_h225_addr(struct nf_conn *ct, unsigned char *data,
 630                  TransportAddress *taddr,
 631                  union nf_inet_addr *addr, __be16 *port)
 632{
 633        const unsigned char *p;
 634        int len;
 635
 636        switch (taddr->choice) {
 637        case eTransportAddress_ipAddress:
 638                if (nf_ct_l3num(ct) != AF_INET)
 639                        return 0;
 640                p = data + taddr->ipAddress.ip;
 641                len = 4;
 642                break;
 643        case eTransportAddress_ip6Address:
 644                if (nf_ct_l3num(ct) != AF_INET6)
 645                        return 0;
 646                p = data + taddr->ip6Address.ip;
 647                len = 16;
 648                break;
 649        default:
 650                return 0;
 651        }
 652
 653        memcpy(addr, p, len);
 654        memset((void *)addr + len, 0, sizeof(*addr) - len);
 655        memcpy(port, p + len, sizeof(__be16));
 656
 657        return 1;
 658}
 659
 660/****************************************************************************/
 661static int expect_h245(struct sk_buff *skb, struct nf_conn *ct,
 662                       enum ip_conntrack_info ctinfo,
 663                       unsigned char **data, int dataoff,
 664                       TransportAddress *taddr)
 665{
 666        int dir = CTINFO2DIR(ctinfo);
 667        int ret = 0;
 668        __be16 port;
 669        union nf_inet_addr addr;
 670        struct nf_conntrack_expect *exp;
 671        typeof(nat_h245_hook) nat_h245;
 672
 673        /* Read h245Address */
 674        if (!get_h225_addr(ct, *data, taddr, &addr, &port) ||
 675            memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
 676            port == 0)
 677                return 0;
 678
 679        /* Create expect for h245 connection */
 680        if ((exp = nf_ct_expect_alloc(ct)) == NULL)
 681                return -1;
 682        nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 683                          &ct->tuplehash[!dir].tuple.src.u3,
 684                          &ct->tuplehash[!dir].tuple.dst.u3,
 685                          IPPROTO_TCP, NULL, &port);
 686        exp->helper = &nf_conntrack_helper_h245;
 687
 688        if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 689                   &ct->tuplehash[!dir].tuple.dst.u3,
 690                   sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 691            (nat_h245 = rcu_dereference(nat_h245_hook)) &&
 692            ct->status & IPS_NAT_MASK) {
 693                /* NAT needed */
 694                ret = nat_h245(skb, ct, ctinfo, data, dataoff, taddr,
 695                               port, exp);
 696        } else {                /* Conntrack only */
 697                if (nf_ct_expect_related(exp) == 0) {
 698                        pr_debug("nf_ct_q931: expect H.245 ");
 699                        nf_ct_dump_tuple(&exp->tuple);
 700                } else
 701                        ret = -1;
 702        }
 703
 704        nf_ct_expect_put(exp);
 705
 706        return ret;
 707}
 708
 709/* If the calling party is on the same side of the forward-to party,
 710 * we don't need to track the second call */
 711static int callforward_do_filter(const union nf_inet_addr *src,
 712                                 const union nf_inet_addr *dst,
 713                                 u_int8_t family)
 714{
 715        const struct nf_afinfo *afinfo;
 716        struct flowi fl1, fl2;
 717        int ret = 0;
 718
 719        /* rcu_read_lock()ed by nf_hook_slow() */
 720        afinfo = nf_get_afinfo(family);
 721        if (!afinfo)
 722                return 0;
 723
 724        memset(&fl1, 0, sizeof(fl1));
 725        memset(&fl2, 0, sizeof(fl2));
 726
 727        switch (family) {
 728        case AF_INET: {
 729                struct rtable *rt1, *rt2;
 730
 731                fl1.fl4_dst = src->ip;
 732                fl2.fl4_dst = dst->ip;
 733                if (!afinfo->route((struct dst_entry **)&rt1, &fl1)) {
 734                        if (!afinfo->route((struct dst_entry **)&rt2, &fl2)) {
 735                                if (rt1->rt_gateway == rt2->rt_gateway &&
 736                                    rt1->u.dst.dev  == rt2->u.dst.dev)
 737                                        ret = 1;
 738                                dst_release(&rt2->u.dst);
 739                        }
 740                        dst_release(&rt1->u.dst);
 741                }
 742                break;
 743        }
 744#if defined(CONFIG_NF_CONNTRACK_IPV6) || \
 745    defined(CONFIG_NF_CONNTRACK_IPV6_MODULE)
 746        case AF_INET6: {
 747                struct rt6_info *rt1, *rt2;
 748
 749                memcpy(&fl1.fl6_dst, src, sizeof(fl1.fl6_dst));
 750                memcpy(&fl2.fl6_dst, dst, sizeof(fl2.fl6_dst));
 751                if (!afinfo->route((struct dst_entry **)&rt1, &fl1)) {
 752                        if (!afinfo->route((struct dst_entry **)&rt2, &fl2)) {
 753                                if (!memcmp(&rt1->rt6i_gateway, &rt2->rt6i_gateway,
 754                                            sizeof(rt1->rt6i_gateway)) &&
 755                                    rt1->u.dst.dev == rt2->u.dst.dev)
 756                                        ret = 1;
 757                                dst_release(&rt2->u.dst);
 758                        }
 759                        dst_release(&rt1->u.dst);
 760                }
 761                break;
 762        }
 763#endif
 764        }
 765        return ret;
 766
 767}
 768
 769/****************************************************************************/
 770static int expect_callforwarding(struct sk_buff *skb,
 771                                 struct nf_conn *ct,
 772                                 enum ip_conntrack_info ctinfo,
 773                                 unsigned char **data, int dataoff,
 774                                 TransportAddress *taddr)
 775{
 776        int dir = CTINFO2DIR(ctinfo);
 777        int ret = 0;
 778        __be16 port;
 779        union nf_inet_addr addr;
 780        struct nf_conntrack_expect *exp;
 781        typeof(nat_callforwarding_hook) nat_callforwarding;
 782
 783        /* Read alternativeAddress */
 784        if (!get_h225_addr(ct, *data, taddr, &addr, &port) || port == 0)
 785                return 0;
 786
 787        /* If the calling party is on the same side of the forward-to party,
 788         * we don't need to track the second call */
 789        if (callforward_filter &&
 790            callforward_do_filter(&addr, &ct->tuplehash[!dir].tuple.src.u3,
 791                                  nf_ct_l3num(ct))) {
 792                pr_debug("nf_ct_q931: Call Forwarding not tracked\n");
 793                return 0;
 794        }
 795
 796        /* Create expect for the second call leg */
 797        if ((exp = nf_ct_expect_alloc(ct)) == NULL)
 798                return -1;
 799        nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
 800                          &ct->tuplehash[!dir].tuple.src.u3, &addr,
 801                          IPPROTO_TCP, NULL, &port);
 802        exp->helper = nf_conntrack_helper_q931;
 803
 804        if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
 805                   &ct->tuplehash[!dir].tuple.dst.u3,
 806                   sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
 807            (nat_callforwarding = rcu_dereference(nat_callforwarding_hook)) &&
 808            ct->status & IPS_NAT_MASK) {
 809                /* Need NAT */
 810                ret = nat_callforwarding(skb, ct, ctinfo, data, dataoff,
 811                                         taddr, port, exp);
 812        } else {                /* Conntrack only */
 813                if (nf_ct_expect_related(exp) == 0) {
 814                        pr_debug("nf_ct_q931: expect Call Forwarding ");
 815                        nf_ct_dump_tuple(&exp->tuple);
 816                } else
 817                        ret = -1;
 818        }
 819
 820        nf_ct_expect_put(exp);
 821
 822        return ret;
 823}
 824
 825/****************************************************************************/
 826static int process_setup(struct sk_buff *skb, struct nf_conn *ct,
 827                         enum ip_conntrack_info ctinfo,
 828                         unsigned char **data, int dataoff,
 829                         Setup_UUIE *setup)
 830{
 831        int dir = CTINFO2DIR(ctinfo);
 832        int ret;
 833        int i;
 834        __be16 port;
 835        union nf_inet_addr addr;
 836        typeof(set_h225_addr_hook) set_h225_addr;
 837
 838        pr_debug("nf_ct_q931: Setup\n");
 839
 840        if (setup->options & eSetup_UUIE_h245Address) {
 841                ret = expect_h245(skb, ct, ctinfo, data, dataoff,
 842                                  &setup->h245Address);
 843                if (ret < 0)
 844                        return -1;
 845        }
 846
 847        set_h225_addr = rcu_dereference(set_h225_addr_hook);
 848        if ((setup->options & eSetup_UUIE_destCallSignalAddress) &&
 849            (set_h225_addr) && ct->status & IPS_NAT_MASK &&
 850            get_h225_addr(ct, *data, &setup->destCallSignalAddress,
 851                          &addr, &port) &&
 852            memcmp(&addr, &ct->tuplehash[!dir].tuple.src.u3, sizeof(addr))) {
 853                pr_debug("nf_ct_q931: set destCallSignalAddress %pI6:%hu->%pI6:%hu\n",
 854                         &addr, ntohs(port), &ct->tuplehash[!dir].tuple.src.u3,
 855                         ntohs(ct->tuplehash[!dir].tuple.src.u.tcp.port));
 856                ret = set_h225_addr(skb, data, dataoff,
 857                                    &setup->destCallSignalAddress,
 858                                    &ct->tuplehash[!dir].tuple.src.u3,
 859                                    ct->tuplehash[!dir].tuple.src.u.tcp.port);
 860                if (ret < 0)
 861                        return -1;
 862        }
 863
 864        if ((setup->options & eSetup_UUIE_sourceCallSignalAddress) &&
 865            (set_h225_addr) && ct->status & IPS_NAT_MASK &&
 866            get_h225_addr(ct, *data, &setup->sourceCallSignalAddress,
 867                          &addr, &port) &&
 868            memcmp(&addr, &ct->tuplehash[!dir].tuple.dst.u3, sizeof(addr))) {
 869                pr_debug("nf_ct_q931: set sourceCallSignalAddress %pI6:%hu->%pI6:%hu\n",
 870                         &addr, ntohs(port), &ct->tuplehash[!dir].tuple.dst.u3,
 871                         ntohs(ct->tuplehash[!dir].tuple.dst.u.tcp.port));
 872                ret = set_h225_addr(skb, data, dataoff,
 873                                    &setup->sourceCallSignalAddress,
 874                                    &ct->tuplehash[!dir].tuple.dst.u3,
 875                                    ct->tuplehash[!dir].tuple.dst.u.tcp.port);
 876                if (ret < 0)
 877                        return -1;
 878        }
 879
 880        if (setup->options & eSetup_UUIE_fastStart) {
 881                for (i = 0; i < setup->fastStart.count; i++) {
 882                        ret = process_olc(skb, ct, ctinfo, data, dataoff,
 883                                          &setup->fastStart.item[i]);
 884                        if (ret < 0)
 885                                return -1;
 886                }
 887        }
 888
 889        return 0;
 890}
 891
 892/****************************************************************************/
 893static int process_callproceeding(struct sk_buff *skb,
 894                                  struct nf_conn *ct,
 895                                  enum ip_conntrack_info ctinfo,
 896                                  unsigned char **data, int dataoff,
 897                                  CallProceeding_UUIE *callproc)
 898{
 899        int ret;
 900        int i;
 901
 902        pr_debug("nf_ct_q931: CallProceeding\n");
 903
 904        if (callproc->options & eCallProceeding_UUIE_h245Address) {
 905                ret = expect_h245(skb, ct, ctinfo, data, dataoff,
 906                                  &callproc->h245Address);
 907                if (ret < 0)
 908                        return -1;
 909        }
 910
 911        if (callproc->options & eCallProceeding_UUIE_fastStart) {
 912                for (i = 0; i < callproc->fastStart.count; i++) {
 913                        ret = process_olc(skb, ct, ctinfo, data, dataoff,
 914                                          &callproc->fastStart.item[i]);
 915                        if (ret < 0)
 916                                return -1;
 917                }
 918        }
 919
 920        return 0;
 921}
 922
 923/****************************************************************************/
 924static int process_connect(struct sk_buff *skb, struct nf_conn *ct,
 925                           enum ip_conntrack_info ctinfo,
 926                           unsigned char **data, int dataoff,
 927                           Connect_UUIE *connect)
 928{
 929        int ret;
 930        int i;
 931
 932        pr_debug("nf_ct_q931: Connect\n");
 933
 934        if (connect->options & eConnect_UUIE_h245Address) {
 935                ret = expect_h245(skb, ct, ctinfo, data, dataoff,
 936                                  &connect->h245Address);
 937                if (ret < 0)
 938                        return -1;
 939        }
 940
 941        if (connect->options & eConnect_UUIE_fastStart) {
 942                for (i = 0; i < connect->fastStart.count; i++) {
 943                        ret = process_olc(skb, ct, ctinfo, data, dataoff,
 944                                          &connect->fastStart.item[i]);
 945                        if (ret < 0)
 946                                return -1;
 947                }
 948        }
 949
 950        return 0;
 951}
 952
 953/****************************************************************************/
 954static int process_alerting(struct sk_buff *skb, struct nf_conn *ct,
 955                            enum ip_conntrack_info ctinfo,
 956                            unsigned char **data, int dataoff,
 957                            Alerting_UUIE *alert)
 958{
 959        int ret;
 960        int i;
 961
 962        pr_debug("nf_ct_q931: Alerting\n");
 963
 964        if (alert->options & eAlerting_UUIE_h245Address) {
 965                ret = expect_h245(skb, ct, ctinfo, data, dataoff,
 966                                  &alert->h245Address);
 967                if (ret < 0)
 968                        return -1;
 969        }
 970
 971        if (alert->options & eAlerting_UUIE_fastStart) {
 972                for (i = 0; i < alert->fastStart.count; i++) {
 973                        ret = process_olc(skb, ct, ctinfo, data, dataoff,
 974                                          &alert->fastStart.item[i]);
 975                        if (ret < 0)
 976                                return -1;
 977                }
 978        }
 979
 980        return 0;
 981}
 982
 983/****************************************************************************/
 984static int process_facility(struct sk_buff *skb, struct nf_conn *ct,
 985                            enum ip_conntrack_info ctinfo,
 986                            unsigned char **data, int dataoff,
 987                            Facility_UUIE *facility)
 988{
 989        int ret;
 990        int i;
 991
 992        pr_debug("nf_ct_q931: Facility\n");
 993
 994        if (facility->reason.choice == eFacilityReason_callForwarded) {
 995                if (facility->options & eFacility_UUIE_alternativeAddress)
 996                        return expect_callforwarding(skb, ct, ctinfo, data,
 997                                                     dataoff,
 998                                                     &facility->
 999                                                     alternativeAddress);
1000                return 0;
1001        }
1002
1003        if (facility->options & eFacility_UUIE_h245Address) {
1004                ret = expect_h245(skb, ct, ctinfo, data, dataoff,
1005                                  &facility->h245Address);
1006                if (ret < 0)
1007                        return -1;
1008        }
1009
1010        if (facility->options & eFacility_UUIE_fastStart) {
1011                for (i = 0; i < facility->fastStart.count; i++) {
1012                        ret = process_olc(skb, ct, ctinfo, data, dataoff,
1013                                          &facility->fastStart.item[i]);
1014                        if (ret < 0)
1015                                return -1;
1016                }
1017        }
1018
1019        return 0;
1020}
1021
1022/****************************************************************************/
1023static int process_progress(struct sk_buff *skb, struct nf_conn *ct,
1024                            enum ip_conntrack_info ctinfo,
1025                            unsigned char **data, int dataoff,
1026                            Progress_UUIE *progress)
1027{
1028        int ret;
1029        int i;
1030
1031        pr_debug("nf_ct_q931: Progress\n");
1032
1033        if (progress->options & eProgress_UUIE_h245Address) {
1034                ret = expect_h245(skb, ct, ctinfo, data, dataoff,
1035                                  &progress->h245Address);
1036                if (ret < 0)
1037                        return -1;
1038        }
1039
1040        if (progress->options & eProgress_UUIE_fastStart) {
1041                for (i = 0; i < progress->fastStart.count; i++) {
1042                        ret = process_olc(skb, ct, ctinfo, data, dataoff,
1043                                          &progress->fastStart.item[i]);
1044                        if (ret < 0)
1045                                return -1;
1046                }
1047        }
1048
1049        return 0;
1050}
1051
1052/****************************************************************************/
1053static int process_q931(struct sk_buff *skb, struct nf_conn *ct,
1054                        enum ip_conntrack_info ctinfo,
1055                        unsigned char **data, int dataoff, Q931 *q931)
1056{
1057        H323_UU_PDU *pdu = &q931->UUIE.h323_uu_pdu;
1058        int i;
1059        int ret = 0;
1060
1061        switch (pdu->h323_message_body.choice) {
1062        case eH323_UU_PDU_h323_message_body_setup:
1063                ret = process_setup(skb, ct, ctinfo, data, dataoff,
1064                                    &pdu->h323_message_body.setup);
1065                break;
1066        case eH323_UU_PDU_h323_message_body_callProceeding:
1067                ret = process_callproceeding(skb, ct, ctinfo, data, dataoff,
1068                                             &pdu->h323_message_body.
1069                                             callProceeding);
1070                break;
1071        case eH323_UU_PDU_h323_message_body_connect:
1072                ret = process_connect(skb, ct, ctinfo, data, dataoff,
1073                                      &pdu->h323_message_body.connect);
1074                break;
1075        case eH323_UU_PDU_h323_message_body_alerting:
1076                ret = process_alerting(skb, ct, ctinfo, data, dataoff,
1077                                       &pdu->h323_message_body.alerting);
1078                break;
1079        case eH323_UU_PDU_h323_message_body_facility:
1080                ret = process_facility(skb, ct, ctinfo, data, dataoff,
1081                                       &pdu->h323_message_body.facility);
1082                break;
1083        case eH323_UU_PDU_h323_message_body_progress:
1084                ret = process_progress(skb, ct, ctinfo, data, dataoff,
1085                                       &pdu->h323_message_body.progress);
1086                break;
1087        default:
1088                pr_debug("nf_ct_q931: Q.931 signal %d\n",
1089                         pdu->h323_message_body.choice);
1090                break;
1091        }
1092
1093        if (ret < 0)
1094                return -1;
1095
1096        if (pdu->options & eH323_UU_PDU_h245Control) {
1097                for (i = 0; i < pdu->h245Control.count; i++) {
1098                        ret = process_h245(skb, ct, ctinfo, data, dataoff,
1099                                           &pdu->h245Control.item[i]);
1100                        if (ret < 0)
1101                                return -1;
1102                }
1103        }
1104
1105        return 0;
1106}
1107
1108/****************************************************************************/
1109static int q931_help(struct sk_buff *skb, unsigned int protoff,
1110                     struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1111{
1112        static Q931 q931;
1113        unsigned char *data = NULL;
1114        int datalen;
1115        int dataoff;
1116        int ret;
1117
1118        /* Until there's been traffic both ways, don't look in packets. */
1119        if (ctinfo != IP_CT_ESTABLISHED &&
1120            ctinfo != IP_CT_ESTABLISHED + IP_CT_IS_REPLY) {
1121                return NF_ACCEPT;
1122        }
1123        pr_debug("nf_ct_q931: skblen = %u\n", skb->len);
1124
1125        spin_lock_bh(&nf_h323_lock);
1126
1127        /* Process each TPKT */
1128        while (get_tpkt_data(skb, protoff, ct, ctinfo,
1129                             &data, &datalen, &dataoff)) {
1130                pr_debug("nf_ct_q931: TPKT len=%d ", datalen);
1131                nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1132
1133                /* Decode Q.931 signal */
1134                ret = DecodeQ931(data, datalen, &q931);
1135                if (ret < 0) {
1136                        pr_debug("nf_ct_q931: decoding error: %s\n",
1137                                 ret == H323_ERROR_BOUND ?
1138                                 "out of bound" : "out of range");
1139                        /* We don't drop when decoding error */
1140                        break;
1141                }
1142
1143                /* Process Q.931 signal */
1144                if (process_q931(skb, ct, ctinfo, &data, dataoff, &q931) < 0)
1145                        goto drop;
1146        }
1147
1148        spin_unlock_bh(&nf_h323_lock);
1149        return NF_ACCEPT;
1150
1151      drop:
1152        spin_unlock_bh(&nf_h323_lock);
1153        if (net_ratelimit())
1154                printk("nf_ct_q931: packet dropped\n");
1155        return NF_DROP;
1156}
1157
1158/****************************************************************************/
1159static const struct nf_conntrack_expect_policy q931_exp_policy = {
1160        /* T.120 and H.245 */
1161        .max_expected           = H323_RTP_CHANNEL_MAX * 4 + 4,
1162        .timeout                = 240,
1163};
1164
1165static struct nf_conntrack_helper nf_conntrack_helper_q931[] __read_mostly = {
1166        {
1167                .name                   = "Q.931",
1168                .me                     = THIS_MODULE,
1169                .tuple.src.l3num        = AF_INET,
1170                .tuple.src.u.tcp.port   = cpu_to_be16(Q931_PORT),
1171                .tuple.dst.protonum     = IPPROTO_TCP,
1172                .help                   = q931_help,
1173                .expect_policy          = &q931_exp_policy,
1174        },
1175        {
1176                .name                   = "Q.931",
1177                .me                     = THIS_MODULE,
1178                .tuple.src.l3num        = AF_INET6,
1179                .tuple.src.u.tcp.port   = cpu_to_be16(Q931_PORT),
1180                .tuple.dst.protonum     = IPPROTO_TCP,
1181                .help                   = q931_help,
1182                .expect_policy          = &q931_exp_policy,
1183        },
1184};
1185
1186/****************************************************************************/
1187static unsigned char *get_udp_data(struct sk_buff *skb, unsigned int protoff,
1188                                   int *datalen)
1189{
1190        const struct udphdr *uh;
1191        struct udphdr _uh;
1192        int dataoff;
1193
1194        uh = skb_header_pointer(skb, protoff, sizeof(_uh), &_uh);
1195        if (uh == NULL)
1196                return NULL;
1197        dataoff = protoff + sizeof(_uh);
1198        if (dataoff >= skb->len)
1199                return NULL;
1200        *datalen = skb->len - dataoff;
1201        return skb_header_pointer(skb, dataoff, *datalen, h323_buffer);
1202}
1203
1204/****************************************************************************/
1205static struct nf_conntrack_expect *find_expect(struct nf_conn *ct,
1206                                               union nf_inet_addr *addr,
1207                                               __be16 port)
1208{
1209        struct net *net = nf_ct_net(ct);
1210        struct nf_conntrack_expect *exp;
1211        struct nf_conntrack_tuple tuple;
1212
1213        memset(&tuple.src.u3, 0, sizeof(tuple.src.u3));
1214        tuple.src.u.tcp.port = 0;
1215        memcpy(&tuple.dst.u3, addr, sizeof(tuple.dst.u3));
1216        tuple.dst.u.tcp.port = port;
1217        tuple.dst.protonum = IPPROTO_TCP;
1218
1219        exp = __nf_ct_expect_find(net, &tuple);
1220        if (exp && exp->master == ct)
1221                return exp;
1222        return NULL;
1223}
1224
1225/****************************************************************************/
1226static int set_expect_timeout(struct nf_conntrack_expect *exp,
1227                              unsigned timeout)
1228{
1229        if (!exp || !del_timer(&exp->timeout))
1230                return 0;
1231
1232        exp->timeout.expires = jiffies + timeout * HZ;
1233        add_timer(&exp->timeout);
1234
1235        return 1;
1236}
1237
1238/****************************************************************************/
1239static int expect_q931(struct sk_buff *skb, struct nf_conn *ct,
1240                       enum ip_conntrack_info ctinfo,
1241                       unsigned char **data,
1242                       TransportAddress *taddr, int count)
1243{
1244        struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1245        int dir = CTINFO2DIR(ctinfo);
1246        int ret = 0;
1247        int i;
1248        __be16 port;
1249        union nf_inet_addr addr;
1250        struct nf_conntrack_expect *exp;
1251        typeof(nat_q931_hook) nat_q931;
1252
1253        /* Look for the first related address */
1254        for (i = 0; i < count; i++) {
1255                if (get_h225_addr(ct, *data, &taddr[i], &addr, &port) &&
1256                    memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3,
1257                           sizeof(addr)) == 0 && port != 0)
1258                        break;
1259        }
1260
1261        if (i >= count)         /* Not found */
1262                return 0;
1263
1264        /* Create expect for Q.931 */
1265        if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1266                return -1;
1267        nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1268                          gkrouted_only ? /* only accept calls from GK? */
1269                                &ct->tuplehash[!dir].tuple.src.u3 : NULL,
1270                          &ct->tuplehash[!dir].tuple.dst.u3,
1271                          IPPROTO_TCP, NULL, &port);
1272        exp->helper = nf_conntrack_helper_q931;
1273        exp->flags = NF_CT_EXPECT_PERMANENT;    /* Accept multiple calls */
1274
1275        nat_q931 = rcu_dereference(nat_q931_hook);
1276        if (nat_q931 && ct->status & IPS_NAT_MASK) {    /* Need NAT */
1277                ret = nat_q931(skb, ct, ctinfo, data, taddr, i, port, exp);
1278        } else {                /* Conntrack only */
1279                if (nf_ct_expect_related(exp) == 0) {
1280                        pr_debug("nf_ct_ras: expect Q.931 ");
1281                        nf_ct_dump_tuple(&exp->tuple);
1282
1283                        /* Save port for looking up expect in processing RCF */
1284                        info->sig_port[dir] = port;
1285                } else
1286                        ret = -1;
1287        }
1288
1289        nf_ct_expect_put(exp);
1290
1291        return ret;
1292}
1293
1294/****************************************************************************/
1295static int process_grq(struct sk_buff *skb, struct nf_conn *ct,
1296                       enum ip_conntrack_info ctinfo,
1297                       unsigned char **data, GatekeeperRequest *grq)
1298{
1299        typeof(set_ras_addr_hook) set_ras_addr;
1300
1301        pr_debug("nf_ct_ras: GRQ\n");
1302
1303        set_ras_addr = rcu_dereference(set_ras_addr_hook);
1304        if (set_ras_addr && ct->status & IPS_NAT_MASK)  /* NATed */
1305                return set_ras_addr(skb, ct, ctinfo, data,
1306                                    &grq->rasAddress, 1);
1307        return 0;
1308}
1309
1310/****************************************************************************/
1311static int process_gcf(struct sk_buff *skb, struct nf_conn *ct,
1312                       enum ip_conntrack_info ctinfo,
1313                       unsigned char **data, GatekeeperConfirm *gcf)
1314{
1315        int dir = CTINFO2DIR(ctinfo);
1316        int ret = 0;
1317        __be16 port;
1318        union nf_inet_addr addr;
1319        struct nf_conntrack_expect *exp;
1320
1321        pr_debug("nf_ct_ras: GCF\n");
1322
1323        if (!get_h225_addr(ct, *data, &gcf->rasAddress, &addr, &port))
1324                return 0;
1325
1326        /* Registration port is the same as discovery port */
1327        if (!memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1328            port == ct->tuplehash[dir].tuple.src.u.udp.port)
1329                return 0;
1330
1331        /* Avoid RAS expectation loops. A GCF is never expected. */
1332        if (test_bit(IPS_EXPECTED_BIT, &ct->status))
1333                return 0;
1334
1335        /* Need new expect */
1336        if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1337                return -1;
1338        nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1339                          &ct->tuplehash[!dir].tuple.src.u3, &addr,
1340                          IPPROTO_UDP, NULL, &port);
1341        exp->helper = nf_conntrack_helper_ras;
1342
1343        if (nf_ct_expect_related(exp) == 0) {
1344                pr_debug("nf_ct_ras: expect RAS ");
1345                nf_ct_dump_tuple(&exp->tuple);
1346        } else
1347                ret = -1;
1348
1349        nf_ct_expect_put(exp);
1350
1351        return ret;
1352}
1353
1354/****************************************************************************/
1355static int process_rrq(struct sk_buff *skb, struct nf_conn *ct,
1356                       enum ip_conntrack_info ctinfo,
1357                       unsigned char **data, RegistrationRequest *rrq)
1358{
1359        struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1360        int ret;
1361        typeof(set_ras_addr_hook) set_ras_addr;
1362
1363        pr_debug("nf_ct_ras: RRQ\n");
1364
1365        ret = expect_q931(skb, ct, ctinfo, data,
1366                          rrq->callSignalAddress.item,
1367                          rrq->callSignalAddress.count);
1368        if (ret < 0)
1369                return -1;
1370
1371        set_ras_addr = rcu_dereference(set_ras_addr_hook);
1372        if (set_ras_addr && ct->status & IPS_NAT_MASK) {
1373                ret = set_ras_addr(skb, ct, ctinfo, data,
1374                                   rrq->rasAddress.item,
1375                                   rrq->rasAddress.count);
1376                if (ret < 0)
1377                        return -1;
1378        }
1379
1380        if (rrq->options & eRegistrationRequest_timeToLive) {
1381                pr_debug("nf_ct_ras: RRQ TTL = %u seconds\n", rrq->timeToLive);
1382                info->timeout = rrq->timeToLive;
1383        } else
1384                info->timeout = default_rrq_ttl;
1385
1386        return 0;
1387}
1388
1389/****************************************************************************/
1390static int process_rcf(struct sk_buff *skb, struct nf_conn *ct,
1391                       enum ip_conntrack_info ctinfo,
1392                       unsigned char **data, RegistrationConfirm *rcf)
1393{
1394        struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1395        int dir = CTINFO2DIR(ctinfo);
1396        int ret;
1397        struct nf_conntrack_expect *exp;
1398        typeof(set_sig_addr_hook) set_sig_addr;
1399
1400        pr_debug("nf_ct_ras: RCF\n");
1401
1402        set_sig_addr = rcu_dereference(set_sig_addr_hook);
1403        if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1404                ret = set_sig_addr(skb, ct, ctinfo, data,
1405                                        rcf->callSignalAddress.item,
1406                                        rcf->callSignalAddress.count);
1407                if (ret < 0)
1408                        return -1;
1409        }
1410
1411        if (rcf->options & eRegistrationConfirm_timeToLive) {
1412                pr_debug("nf_ct_ras: RCF TTL = %u seconds\n", rcf->timeToLive);
1413                info->timeout = rcf->timeToLive;
1414        }
1415
1416        if (info->timeout > 0) {
1417                pr_debug("nf_ct_ras: set RAS connection timeout to "
1418                         "%u seconds\n", info->timeout);
1419                nf_ct_refresh(ct, skb, info->timeout * HZ);
1420
1421                /* Set expect timeout */
1422                spin_lock_bh(&nf_conntrack_lock);
1423                exp = find_expect(ct, &ct->tuplehash[dir].tuple.dst.u3,
1424                                  info->sig_port[!dir]);
1425                if (exp) {
1426                        pr_debug("nf_ct_ras: set Q.931 expect "
1427                                 "timeout to %u seconds for",
1428                                 info->timeout);
1429                        nf_ct_dump_tuple(&exp->tuple);
1430                        set_expect_timeout(exp, info->timeout);
1431                }
1432                spin_unlock_bh(&nf_conntrack_lock);
1433        }
1434
1435        return 0;
1436}
1437
1438/****************************************************************************/
1439static int process_urq(struct sk_buff *skb, struct nf_conn *ct,
1440                       enum ip_conntrack_info ctinfo,
1441                       unsigned char **data, UnregistrationRequest *urq)
1442{
1443        struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1444        int dir = CTINFO2DIR(ctinfo);
1445        int ret;
1446        typeof(set_sig_addr_hook) set_sig_addr;
1447
1448        pr_debug("nf_ct_ras: URQ\n");
1449
1450        set_sig_addr = rcu_dereference(set_sig_addr_hook);
1451        if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1452                ret = set_sig_addr(skb, ct, ctinfo, data,
1453                                   urq->callSignalAddress.item,
1454                                   urq->callSignalAddress.count);
1455                if (ret < 0)
1456                        return -1;
1457        }
1458
1459        /* Clear old expect */
1460        nf_ct_remove_expectations(ct);
1461        info->sig_port[dir] = 0;
1462        info->sig_port[!dir] = 0;
1463
1464        /* Give it 30 seconds for UCF or URJ */
1465        nf_ct_refresh(ct, skb, 30 * HZ);
1466
1467        return 0;
1468}
1469
1470/****************************************************************************/
1471static int process_arq(struct sk_buff *skb, struct nf_conn *ct,
1472                       enum ip_conntrack_info ctinfo,
1473                       unsigned char **data, AdmissionRequest *arq)
1474{
1475        const struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1476        int dir = CTINFO2DIR(ctinfo);
1477        __be16 port;
1478        union nf_inet_addr addr;
1479        typeof(set_h225_addr_hook) set_h225_addr;
1480
1481        pr_debug("nf_ct_ras: ARQ\n");
1482
1483        set_h225_addr = rcu_dereference(set_h225_addr_hook);
1484        if ((arq->options & eAdmissionRequest_destCallSignalAddress) &&
1485            get_h225_addr(ct, *data, &arq->destCallSignalAddress,
1486                          &addr, &port) &&
1487            !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1488            port == info->sig_port[dir] &&
1489            set_h225_addr && ct->status & IPS_NAT_MASK) {
1490                /* Answering ARQ */
1491                return set_h225_addr(skb, data, 0,
1492                                     &arq->destCallSignalAddress,
1493                                     &ct->tuplehash[!dir].tuple.dst.u3,
1494                                     info->sig_port[!dir]);
1495        }
1496
1497        if ((arq->options & eAdmissionRequest_srcCallSignalAddress) &&
1498            get_h225_addr(ct, *data, &arq->srcCallSignalAddress,
1499                          &addr, &port) &&
1500            !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1501            set_h225_addr && ct->status & IPS_NAT_MASK) {
1502                /* Calling ARQ */
1503                return set_h225_addr(skb, data, 0,
1504                                     &arq->srcCallSignalAddress,
1505                                     &ct->tuplehash[!dir].tuple.dst.u3,
1506                                     port);
1507        }
1508
1509        return 0;
1510}
1511
1512/****************************************************************************/
1513static int process_acf(struct sk_buff *skb, struct nf_conn *ct,
1514                       enum ip_conntrack_info ctinfo,
1515                       unsigned char **data, AdmissionConfirm *acf)
1516{
1517        int dir = CTINFO2DIR(ctinfo);
1518        int ret = 0;
1519        __be16 port;
1520        union nf_inet_addr addr;
1521        struct nf_conntrack_expect *exp;
1522        typeof(set_sig_addr_hook) set_sig_addr;
1523
1524        pr_debug("nf_ct_ras: ACF\n");
1525
1526        if (!get_h225_addr(ct, *data, &acf->destCallSignalAddress,
1527                           &addr, &port))
1528                return 0;
1529
1530        if (!memcmp(&addr, &ct->tuplehash[dir].tuple.dst.u3, sizeof(addr))) {
1531                /* Answering ACF */
1532                set_sig_addr = rcu_dereference(set_sig_addr_hook);
1533                if (set_sig_addr && ct->status & IPS_NAT_MASK)
1534                        return set_sig_addr(skb, ct, ctinfo, data,
1535                                            &acf->destCallSignalAddress, 1);
1536                return 0;
1537        }
1538
1539        /* Need new expect */
1540        if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1541                return -1;
1542        nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1543                          &ct->tuplehash[!dir].tuple.src.u3, &addr,
1544                          IPPROTO_TCP, NULL, &port);
1545        exp->flags = NF_CT_EXPECT_PERMANENT;
1546        exp->helper = nf_conntrack_helper_q931;
1547
1548        if (nf_ct_expect_related(exp) == 0) {
1549                pr_debug("nf_ct_ras: expect Q.931 ");
1550                nf_ct_dump_tuple(&exp->tuple);
1551        } else
1552                ret = -1;
1553
1554        nf_ct_expect_put(exp);
1555
1556        return ret;
1557}
1558
1559/****************************************************************************/
1560static int process_lrq(struct sk_buff *skb, struct nf_conn *ct,
1561                       enum ip_conntrack_info ctinfo,
1562                       unsigned char **data, LocationRequest *lrq)
1563{
1564        typeof(set_ras_addr_hook) set_ras_addr;
1565
1566        pr_debug("nf_ct_ras: LRQ\n");
1567
1568        set_ras_addr = rcu_dereference(set_ras_addr_hook);
1569        if (set_ras_addr && ct->status & IPS_NAT_MASK)
1570                return set_ras_addr(skb, ct, ctinfo, data,
1571                                    &lrq->replyAddress, 1);
1572        return 0;
1573}
1574
1575/****************************************************************************/
1576static int process_lcf(struct sk_buff *skb, struct nf_conn *ct,
1577                       enum ip_conntrack_info ctinfo,
1578                       unsigned char **data, LocationConfirm *lcf)
1579{
1580        int dir = CTINFO2DIR(ctinfo);
1581        int ret = 0;
1582        __be16 port;
1583        union nf_inet_addr addr;
1584        struct nf_conntrack_expect *exp;
1585
1586        pr_debug("nf_ct_ras: LCF\n");
1587
1588        if (!get_h225_addr(ct, *data, &lcf->callSignalAddress,
1589                           &addr, &port))
1590                return 0;
1591
1592        /* Need new expect for call signal */
1593        if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1594                return -1;
1595        nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1596                          &ct->tuplehash[!dir].tuple.src.u3, &addr,
1597                          IPPROTO_TCP, NULL, &port);
1598        exp->flags = NF_CT_EXPECT_PERMANENT;
1599        exp->helper = nf_conntrack_helper_q931;
1600
1601        if (nf_ct_expect_related(exp) == 0) {
1602                pr_debug("nf_ct_ras: expect Q.931 ");
1603                nf_ct_dump_tuple(&exp->tuple);
1604        } else
1605                ret = -1;
1606
1607        nf_ct_expect_put(exp);
1608
1609        /* Ignore rasAddress */
1610
1611        return ret;
1612}
1613
1614/****************************************************************************/
1615static int process_irr(struct sk_buff *skb, struct nf_conn *ct,
1616                       enum ip_conntrack_info ctinfo,
1617                       unsigned char **data, InfoRequestResponse *irr)
1618{
1619        int ret;
1620        typeof(set_ras_addr_hook) set_ras_addr;
1621        typeof(set_sig_addr_hook) set_sig_addr;
1622
1623        pr_debug("nf_ct_ras: IRR\n");
1624
1625        set_ras_addr = rcu_dereference(set_ras_addr_hook);
1626        if (set_ras_addr && ct->status & IPS_NAT_MASK) {
1627                ret = set_ras_addr(skb, ct, ctinfo, data,
1628                                   &irr->rasAddress, 1);
1629                if (ret < 0)
1630                        return -1;
1631        }
1632
1633        set_sig_addr = rcu_dereference(set_sig_addr_hook);
1634        if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1635                ret = set_sig_addr(skb, ct, ctinfo, data,
1636                                        irr->callSignalAddress.item,
1637                                        irr->callSignalAddress.count);
1638                if (ret < 0)
1639                        return -1;
1640        }
1641
1642        return 0;
1643}
1644
1645/****************************************************************************/
1646static int process_ras(struct sk_buff *skb, struct nf_conn *ct,
1647                       enum ip_conntrack_info ctinfo,
1648                       unsigned char **data, RasMessage *ras)
1649{
1650        switch (ras->choice) {
1651        case eRasMessage_gatekeeperRequest:
1652                return process_grq(skb, ct, ctinfo, data,
1653                                   &ras->gatekeeperRequest);
1654        case eRasMessage_gatekeeperConfirm:
1655                return process_gcf(skb, ct, ctinfo, data,
1656                                   &ras->gatekeeperConfirm);
1657        case eRasMessage_registrationRequest:
1658                return process_rrq(skb, ct, ctinfo, data,
1659                                   &ras->registrationRequest);
1660        case eRasMessage_registrationConfirm:
1661                return process_rcf(skb, ct, ctinfo, data,
1662                                   &ras->registrationConfirm);
1663        case eRasMessage_unregistrationRequest:
1664                return process_urq(skb, ct, ctinfo, data,
1665                                   &ras->unregistrationRequest);
1666        case eRasMessage_admissionRequest:
1667                return process_arq(skb, ct, ctinfo, data,
1668                                   &ras->admissionRequest);
1669        case eRasMessage_admissionConfirm:
1670                return process_acf(skb, ct, ctinfo, data,
1671                                   &ras->admissionConfirm);
1672        case eRasMessage_locationRequest:
1673                return process_lrq(skb, ct, ctinfo, data,
1674                                   &ras->locationRequest);
1675        case eRasMessage_locationConfirm:
1676                return process_lcf(skb, ct, ctinfo, data,
1677                                   &ras->locationConfirm);
1678        case eRasMessage_infoRequestResponse:
1679                return process_irr(skb, ct, ctinfo, data,
1680                                   &ras->infoRequestResponse);
1681        default:
1682                pr_debug("nf_ct_ras: RAS message %d\n", ras->choice);
1683                break;
1684        }
1685
1686        return 0;
1687}
1688
1689/****************************************************************************/
1690static int ras_help(struct sk_buff *skb, unsigned int protoff,
1691                    struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1692{
1693        static RasMessage ras;
1694        unsigned char *data;
1695        int datalen = 0;
1696        int ret;
1697
1698        pr_debug("nf_ct_ras: skblen = %u\n", skb->len);
1699
1700        spin_lock_bh(&nf_h323_lock);
1701
1702        /* Get UDP data */
1703        data = get_udp_data(skb, protoff, &datalen);
1704        if (data == NULL)
1705                goto accept;
1706        pr_debug("nf_ct_ras: RAS message len=%d ", datalen);
1707        nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1708
1709        /* Decode RAS message */
1710        ret = DecodeRasMessage(data, datalen, &ras);
1711        if (ret < 0) {
1712                pr_debug("nf_ct_ras: decoding error: %s\n",
1713                         ret == H323_ERROR_BOUND ?
1714                         "out of bound" : "out of range");
1715                goto accept;
1716        }
1717
1718        /* Process RAS message */
1719        if (process_ras(skb, ct, ctinfo, &data, &ras) < 0)
1720                goto drop;
1721
1722      accept:
1723        spin_unlock_bh(&nf_h323_lock);
1724        return NF_ACCEPT;
1725
1726      drop:
1727        spin_unlock_bh(&nf_h323_lock);
1728        if (net_ratelimit())
1729                printk("nf_ct_ras: packet dropped\n");
1730        return NF_DROP;
1731}
1732
1733/****************************************************************************/
1734static const struct nf_conntrack_expect_policy ras_exp_policy = {
1735        .max_expected           = 32,
1736        .timeout                = 240,
1737};
1738
1739static struct nf_conntrack_helper nf_conntrack_helper_ras[] __read_mostly = {
1740        {
1741                .name                   = "RAS",
1742                .me                     = THIS_MODULE,
1743                .tuple.src.l3num        = AF_INET,
1744                .tuple.src.u.udp.port   = cpu_to_be16(RAS_PORT),
1745                .tuple.dst.protonum     = IPPROTO_UDP,
1746                .help                   = ras_help,
1747                .expect_policy          = &ras_exp_policy,
1748        },
1749        {
1750                .name                   = "RAS",
1751                .me                     = THIS_MODULE,
1752                .tuple.src.l3num        = AF_INET6,
1753                .tuple.src.u.udp.port   = cpu_to_be16(RAS_PORT),
1754                .tuple.dst.protonum     = IPPROTO_UDP,
1755                .help                   = ras_help,
1756                .expect_policy          = &ras_exp_policy,
1757        },
1758};
1759
1760/****************************************************************************/
1761static void __exit nf_conntrack_h323_fini(void)
1762{
1763        nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[1]);
1764        nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1765        nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1766        nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1767        nf_conntrack_helper_unregister(&nf_conntrack_helper_h245);
1768        kfree(h323_buffer);
1769        pr_debug("nf_ct_h323: fini\n");
1770}
1771
1772/****************************************************************************/
1773static int __init nf_conntrack_h323_init(void)
1774{
1775        int ret;
1776
1777        h323_buffer = kmalloc(65536, GFP_KERNEL);
1778        if (!h323_buffer)
1779                return -ENOMEM;
1780        ret = nf_conntrack_helper_register(&nf_conntrack_helper_h245);
1781        if (ret < 0)
1782                goto err1;
1783        ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[0]);
1784        if (ret < 0)
1785                goto err2;
1786        ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[1]);
1787        if (ret < 0)
1788                goto err3;
1789        ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[0]);
1790        if (ret < 0)
1791                goto err4;
1792        ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[1]);
1793        if (ret < 0)
1794                goto err5;
1795        pr_debug("nf_ct_h323: init success\n");
1796        return 0;
1797
1798err5:
1799        nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1800err4:
1801        nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1802err3:
1803        nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1804err2:
1805        nf_conntrack_helper_unregister(&nf_conntrack_helper_h245);
1806err1:
1807        kfree(h323_buffer);
1808        return ret;
1809}
1810
1811/****************************************************************************/
1812module_init(nf_conntrack_h323_init);
1813module_exit(nf_conntrack_h323_fini);
1814
1815EXPORT_SYMBOL_GPL(get_h225_addr);
1816EXPORT_SYMBOL_GPL(set_h245_addr_hook);
1817EXPORT_SYMBOL_GPL(set_h225_addr_hook);
1818EXPORT_SYMBOL_GPL(set_sig_addr_hook);
1819EXPORT_SYMBOL_GPL(set_ras_addr_hook);
1820EXPORT_SYMBOL_GPL(nat_rtp_rtcp_hook);
1821EXPORT_SYMBOL_GPL(nat_t120_hook);
1822EXPORT_SYMBOL_GPL(nat_h245_hook);
1823EXPORT_SYMBOL_GPL(nat_callforwarding_hook);
1824EXPORT_SYMBOL_GPL(nat_q931_hook);
1825
1826MODULE_AUTHOR("Jing Min Zhao <zhaojingmin@users.sourceforge.net>");
1827MODULE_DESCRIPTION("H.323 connection tracking helper");
1828MODULE_LICENSE("GPL");
1829MODULE_ALIAS("ip_conntrack_h323");
1830MODULE_ALIAS_NFCT_HELPER("h323");
1831