[NETFILTER]: nf_conntrack: introduce expectation classes and policies
[linux-2.6.git] / net / netfilter / nf_conntrack_h323_main.c
1 /*
2  * H.323 connection tracking helper
3  *
4  * Copyright (c) 2006 Jing Min Zhao <zhaojingmin@users.sourceforge.net>
5  *
6  * This source code is licensed under General Public License version 2.
7  *
8  * Based on the 'brute force' H.323 connection tracking module by
9  * Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
10  *
11  * For more information, please see http://nath323.sourceforge.net/
12  */
13
14 #include <linux/module.h>
15 #include <linux/moduleparam.h>
16 #include <linux/ctype.h>
17 #include <linux/inet.h>
18 #include <linux/in.h>
19 #include <linux/ip.h>
20 #include <linux/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 */
35 static unsigned int default_rrq_ttl __read_mostly = 300;
36 module_param(default_rrq_ttl, uint, 0600);
37 MODULE_PARM_DESC(default_rrq_ttl, "use this TTL if it's missing in RRQ");
38
39 static int gkrouted_only __read_mostly = 1;
40 module_param(gkrouted_only, int, 0600);
41 MODULE_PARM_DESC(gkrouted_only, "only accept calls from gatekeeper");
42
43 static int callforward_filter __read_mostly = 1;
44 module_param(callforward_filter, bool, 0600);
45 MODULE_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 */
50 int (*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;
55 int (*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;
60 int (*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;
65 int (*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;
70 int (*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;
78 int (*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;
84 int (*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;
90 int (*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;
96 int (*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
103 static DEFINE_SPINLOCK(nf_h323_lock);
104 static char *h323_buffer;
105
106 static struct nf_conntrack_helper nf_conntrack_helper_h245;
107 static struct nf_conntrack_helper nf_conntrack_helper_q931[];
108 static struct nf_conntrack_helper nf_conntrack_helper_ras[];
109
110 /****************************************************************************/
111 static 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 /****************************************************************************/
216 static 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 family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
222         int len;
223
224         if (taddr->choice != eH245_TransportAddress_unicastAddress)
225                 return 0;
226
227         switch (taddr->unicastAddress.choice) {
228         case eUnicastAddress_iPAddress:
229                 if (family != AF_INET)
230                         return 0;
231                 p = data + taddr->unicastAddress.iPAddress.network;
232                 len = 4;
233                 break;
234         case eUnicastAddress_iP6Address:
235                 if (family != AF_INET6)
236                         return 0;
237                 p = data + taddr->unicastAddress.iP6Address.network;
238                 len = 16;
239                 break;
240         default:
241                 return 0;
242         }
243
244         memcpy(addr, p, len);
245         memset((void *)addr + len, 0, sizeof(*addr) - len);
246         memcpy(port, p + len, sizeof(__be16));
247
248         return 1;
249 }
250
251 /****************************************************************************/
252 static int expect_rtp_rtcp(struct sk_buff *skb, struct nf_conn *ct,
253                            enum ip_conntrack_info ctinfo,
254                            unsigned char **data, int dataoff,
255                            H245_TransportAddress *taddr)
256 {
257         int dir = CTINFO2DIR(ctinfo);
258         int ret = 0;
259         __be16 port;
260         __be16 rtp_port, rtcp_port;
261         union nf_inet_addr addr;
262         struct nf_conntrack_expect *rtp_exp;
263         struct nf_conntrack_expect *rtcp_exp;
264         typeof(nat_rtp_rtcp_hook) nat_rtp_rtcp;
265
266         /* Read RTP or RTCP address */
267         if (!get_h245_addr(ct, *data, taddr, &addr, &port) ||
268             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
269             port == 0)
270                 return 0;
271
272         /* RTP port is even */
273         port &= htons(~1);
274         rtp_port = port;
275         rtcp_port = htons(ntohs(port) + 1);
276
277         /* Create expect for RTP */
278         if ((rtp_exp = nf_ct_expect_alloc(ct)) == NULL)
279                 return -1;
280         nf_ct_expect_init(rtp_exp, NF_CT_EXPECT_CLASS_DEFAULT,
281                           ct->tuplehash[!dir].tuple.src.l3num,
282                           &ct->tuplehash[!dir].tuple.src.u3,
283                           &ct->tuplehash[!dir].tuple.dst.u3,
284                           IPPROTO_UDP, NULL, &rtp_port);
285
286         /* Create expect for RTCP */
287         if ((rtcp_exp = nf_ct_expect_alloc(ct)) == NULL) {
288                 nf_ct_expect_put(rtp_exp);
289                 return -1;
290         }
291         nf_ct_expect_init(rtcp_exp, NF_CT_EXPECT_CLASS_DEFAULT,
292                           ct->tuplehash[!dir].tuple.src.l3num,
293                           &ct->tuplehash[!dir].tuple.src.u3,
294                           &ct->tuplehash[!dir].tuple.dst.u3,
295                           IPPROTO_UDP, NULL, &rtcp_port);
296
297         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
298                    &ct->tuplehash[!dir].tuple.dst.u3,
299                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
300                    (nat_rtp_rtcp = rcu_dereference(nat_rtp_rtcp_hook)) &&
301                    ct->status & IPS_NAT_MASK) {
302                 /* NAT needed */
303                 ret = nat_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
304                                    taddr, port, rtp_port, rtp_exp, rtcp_exp);
305         } else {                /* Conntrack only */
306                 if (nf_ct_expect_related(rtp_exp) == 0) {
307                         if (nf_ct_expect_related(rtcp_exp) == 0) {
308                                 pr_debug("nf_ct_h323: expect RTP ");
309                                 NF_CT_DUMP_TUPLE(&rtp_exp->tuple);
310                                 pr_debug("nf_ct_h323: expect RTCP ");
311                                 NF_CT_DUMP_TUPLE(&rtcp_exp->tuple);
312                         } else {
313                                 nf_ct_unexpect_related(rtp_exp);
314                                 ret = -1;
315                         }
316                 } else
317                         ret = -1;
318         }
319
320         nf_ct_expect_put(rtp_exp);
321         nf_ct_expect_put(rtcp_exp);
322
323         return ret;
324 }
325
326 /****************************************************************************/
327 static int expect_t120(struct sk_buff *skb,
328                        struct nf_conn *ct,
329                        enum ip_conntrack_info ctinfo,
330                        unsigned char **data, int dataoff,
331                        H245_TransportAddress *taddr)
332 {
333         int dir = CTINFO2DIR(ctinfo);
334         int ret = 0;
335         __be16 port;
336         union nf_inet_addr addr;
337         struct nf_conntrack_expect *exp;
338         typeof(nat_t120_hook) nat_t120;
339
340         /* Read T.120 address */
341         if (!get_h245_addr(ct, *data, taddr, &addr, &port) ||
342             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
343             port == 0)
344                 return 0;
345
346         /* Create expect for T.120 connections */
347         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
348                 return -1;
349         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT,
350                           ct->tuplehash[!dir].tuple.src.l3num,
351                           &ct->tuplehash[!dir].tuple.src.u3,
352                           &ct->tuplehash[!dir].tuple.dst.u3,
353                           IPPROTO_TCP, NULL, &port);
354         exp->flags = NF_CT_EXPECT_PERMANENT;    /* Accept multiple channels */
355
356         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
357                    &ct->tuplehash[!dir].tuple.dst.u3,
358                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
359             (nat_t120 = rcu_dereference(nat_t120_hook)) &&
360             ct->status & IPS_NAT_MASK) {
361                 /* NAT needed */
362                 ret = nat_t120(skb, ct, ctinfo, data, dataoff, taddr,
363                                port, exp);
364         } else {                /* Conntrack only */
365                 if (nf_ct_expect_related(exp) == 0) {
366                         pr_debug("nf_ct_h323: expect T.120 ");
367                         NF_CT_DUMP_TUPLE(&exp->tuple);
368                 } else
369                         ret = -1;
370         }
371
372         nf_ct_expect_put(exp);
373
374         return ret;
375 }
376
377 /****************************************************************************/
378 static int process_h245_channel(struct sk_buff *skb,
379                                 struct nf_conn *ct,
380                                 enum ip_conntrack_info ctinfo,
381                                 unsigned char **data, int dataoff,
382                                 H2250LogicalChannelParameters *channel)
383 {
384         int ret;
385
386         if (channel->options & eH2250LogicalChannelParameters_mediaChannel) {
387                 /* RTP */
388                 ret = expect_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
389                                       &channel->mediaChannel);
390                 if (ret < 0)
391                         return -1;
392         }
393
394         if (channel->
395             options & eH2250LogicalChannelParameters_mediaControlChannel) {
396                 /* RTCP */
397                 ret = expect_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
398                                       &channel->mediaControlChannel);
399                 if (ret < 0)
400                         return -1;
401         }
402
403         return 0;
404 }
405
406 /****************************************************************************/
407 static int process_olc(struct sk_buff *skb, struct nf_conn *ct,
408                        enum ip_conntrack_info ctinfo,
409                        unsigned char **data, int dataoff,
410                        OpenLogicalChannel *olc)
411 {
412         int ret;
413
414         pr_debug("nf_ct_h323: OpenLogicalChannel\n");
415
416         if (olc->forwardLogicalChannelParameters.multiplexParameters.choice ==
417             eOpenLogicalChannel_forwardLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters)
418         {
419                 ret = process_h245_channel(skb, ct, ctinfo, data, dataoff,
420                                            &olc->
421                                            forwardLogicalChannelParameters.
422                                            multiplexParameters.
423                                            h2250LogicalChannelParameters);
424                 if (ret < 0)
425                         return -1;
426         }
427
428         if ((olc->options &
429              eOpenLogicalChannel_reverseLogicalChannelParameters) &&
430             (olc->reverseLogicalChannelParameters.options &
431              eOpenLogicalChannel_reverseLogicalChannelParameters_multiplexParameters)
432             && (olc->reverseLogicalChannelParameters.multiplexParameters.
433                 choice ==
434                 eOpenLogicalChannel_reverseLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters))
435         {
436                 ret =
437                     process_h245_channel(skb, ct, ctinfo, data, dataoff,
438                                          &olc->
439                                          reverseLogicalChannelParameters.
440                                          multiplexParameters.
441                                          h2250LogicalChannelParameters);
442                 if (ret < 0)
443                         return -1;
444         }
445
446         if ((olc->options & eOpenLogicalChannel_separateStack) &&
447             olc->forwardLogicalChannelParameters.dataType.choice ==
448             eDataType_data &&
449             olc->forwardLogicalChannelParameters.dataType.data.application.
450             choice == eDataApplicationCapability_application_t120 &&
451             olc->forwardLogicalChannelParameters.dataType.data.application.
452             t120.choice == eDataProtocolCapability_separateLANStack &&
453             olc->separateStack.networkAddress.choice ==
454             eNetworkAccessParameters_networkAddress_localAreaAddress) {
455                 ret = expect_t120(skb, ct, ctinfo, data, dataoff,
456                                   &olc->separateStack.networkAddress.
457                                   localAreaAddress);
458                 if (ret < 0)
459                         return -1;
460         }
461
462         return 0;
463 }
464
465 /****************************************************************************/
466 static int process_olca(struct sk_buff *skb, struct nf_conn *ct,
467                         enum ip_conntrack_info ctinfo,
468                         unsigned char **data, int dataoff,
469                         OpenLogicalChannelAck *olca)
470 {
471         H2250LogicalChannelAckParameters *ack;
472         int ret;
473
474         pr_debug("nf_ct_h323: OpenLogicalChannelAck\n");
475
476         if ((olca->options &
477              eOpenLogicalChannelAck_reverseLogicalChannelParameters) &&
478             (olca->reverseLogicalChannelParameters.options &
479              eOpenLogicalChannelAck_reverseLogicalChannelParameters_multiplexParameters)
480             && (olca->reverseLogicalChannelParameters.multiplexParameters.
481                 choice ==
482                 eOpenLogicalChannelAck_reverseLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters))
483         {
484                 ret = process_h245_channel(skb, ct, ctinfo, data, dataoff,
485                                            &olca->
486                                            reverseLogicalChannelParameters.
487                                            multiplexParameters.
488                                            h2250LogicalChannelParameters);
489                 if (ret < 0)
490                         return -1;
491         }
492
493         if ((olca->options &
494              eOpenLogicalChannelAck_forwardMultiplexAckParameters) &&
495             (olca->forwardMultiplexAckParameters.choice ==
496              eOpenLogicalChannelAck_forwardMultiplexAckParameters_h2250LogicalChannelAckParameters))
497         {
498                 ack = &olca->forwardMultiplexAckParameters.
499                     h2250LogicalChannelAckParameters;
500                 if (ack->options &
501                     eH2250LogicalChannelAckParameters_mediaChannel) {
502                         /* RTP */
503                         ret = expect_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
504                                               &ack->mediaChannel);
505                         if (ret < 0)
506                                 return -1;
507                 }
508
509                 if (ack->options &
510                     eH2250LogicalChannelAckParameters_mediaControlChannel) {
511                         /* RTCP */
512                         ret = expect_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
513                                               &ack->mediaControlChannel);
514                         if (ret < 0)
515                                 return -1;
516                 }
517         }
518
519         if ((olca->options & eOpenLogicalChannelAck_separateStack) &&
520                 olca->separateStack.networkAddress.choice ==
521                 eNetworkAccessParameters_networkAddress_localAreaAddress) {
522                 ret = expect_t120(skb, ct, ctinfo, data, dataoff,
523                                   &olca->separateStack.networkAddress.
524                                   localAreaAddress);
525                 if (ret < 0)
526                         return -1;
527         }
528
529         return 0;
530 }
531
532 /****************************************************************************/
533 static int process_h245(struct sk_buff *skb, struct nf_conn *ct,
534                         enum ip_conntrack_info ctinfo,
535                         unsigned char **data, int dataoff,
536                         MultimediaSystemControlMessage *mscm)
537 {
538         switch (mscm->choice) {
539         case eMultimediaSystemControlMessage_request:
540                 if (mscm->request.choice ==
541                     eRequestMessage_openLogicalChannel) {
542                         return process_olc(skb, ct, ctinfo, data, dataoff,
543                                            &mscm->request.openLogicalChannel);
544                 }
545                 pr_debug("nf_ct_h323: H.245 Request %d\n",
546                          mscm->request.choice);
547                 break;
548         case eMultimediaSystemControlMessage_response:
549                 if (mscm->response.choice ==
550                     eResponseMessage_openLogicalChannelAck) {
551                         return process_olca(skb, ct, ctinfo, data, dataoff,
552                                             &mscm->response.
553                                             openLogicalChannelAck);
554                 }
555                 pr_debug("nf_ct_h323: H.245 Response %d\n",
556                          mscm->response.choice);
557                 break;
558         default:
559                 pr_debug("nf_ct_h323: H.245 signal %d\n", mscm->choice);
560                 break;
561         }
562
563         return 0;
564 }
565
566 /****************************************************************************/
567 static int h245_help(struct sk_buff *skb, unsigned int protoff,
568                      struct nf_conn *ct, enum ip_conntrack_info ctinfo)
569 {
570         static MultimediaSystemControlMessage mscm;
571         unsigned char *data = NULL;
572         int datalen;
573         int dataoff;
574         int ret;
575
576         /* Until there's been traffic both ways, don't look in packets. */
577         if (ctinfo != IP_CT_ESTABLISHED &&
578             ctinfo != IP_CT_ESTABLISHED + IP_CT_IS_REPLY) {
579                 return NF_ACCEPT;
580         }
581         pr_debug("nf_ct_h245: skblen = %u\n", skb->len);
582
583         spin_lock_bh(&nf_h323_lock);
584
585         /* Process each TPKT */
586         while (get_tpkt_data(skb, protoff, ct, ctinfo,
587                              &data, &datalen, &dataoff)) {
588                 pr_debug("nf_ct_h245: TPKT len=%d ", datalen);
589                 NF_CT_DUMP_TUPLE(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
590
591                 /* Decode H.245 signal */
592                 ret = DecodeMultimediaSystemControlMessage(data, datalen,
593                                                            &mscm);
594                 if (ret < 0) {
595                         pr_debug("nf_ct_h245: decoding error: %s\n",
596                                  ret == H323_ERROR_BOUND ?
597                                  "out of bound" : "out of range");
598                         /* We don't drop when decoding error */
599                         break;
600                 }
601
602                 /* Process H.245 signal */
603                 if (process_h245(skb, ct, ctinfo, &data, dataoff, &mscm) < 0)
604                         goto drop;
605         }
606
607         spin_unlock_bh(&nf_h323_lock);
608         return NF_ACCEPT;
609
610       drop:
611         spin_unlock_bh(&nf_h323_lock);
612         if (net_ratelimit())
613                 printk("nf_ct_h245: packet dropped\n");
614         return NF_DROP;
615 }
616
617 /****************************************************************************/
618 static const struct nf_conntrack_expect_policy h245_exp_policy = {
619         .max_expected   = H323_RTP_CHANNEL_MAX * 4 + 2 /* T.120 */,
620         .timeout        = 240,
621 };
622
623 static struct nf_conntrack_helper nf_conntrack_helper_h245 __read_mostly = {
624         .name                   = "H.245",
625         .me                     = THIS_MODULE,
626         .tuple.dst.protonum     = IPPROTO_UDP,
627         .help                   = h245_help,
628         .expect_policy          = &h245_exp_policy,
629 };
630
631 /****************************************************************************/
632 int get_h225_addr(struct nf_conn *ct, unsigned char *data,
633                   TransportAddress *taddr,
634                   union nf_inet_addr *addr, __be16 *port)
635 {
636         const unsigned char *p;
637         int family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
638         int len;
639
640         switch (taddr->choice) {
641         case eTransportAddress_ipAddress:
642                 if (family != AF_INET)
643                         return 0;
644                 p = data + taddr->ipAddress.ip;
645                 len = 4;
646                 break;
647         case eTransportAddress_ip6Address:
648                 if (family != AF_INET6)
649                         return 0;
650                 p = data + taddr->ip6Address.ip;
651                 len = 16;
652                 break;
653         default:
654                 return 0;
655         }
656
657         memcpy(addr, p, len);
658         memset((void *)addr + len, 0, sizeof(*addr) - len);
659         memcpy(port, p + len, sizeof(__be16));
660
661         return 1;
662 }
663
664 /****************************************************************************/
665 static int expect_h245(struct sk_buff *skb, struct nf_conn *ct,
666                        enum ip_conntrack_info ctinfo,
667                        unsigned char **data, int dataoff,
668                        TransportAddress *taddr)
669 {
670         int dir = CTINFO2DIR(ctinfo);
671         int ret = 0;
672         __be16 port;
673         union nf_inet_addr addr;
674         struct nf_conntrack_expect *exp;
675         typeof(nat_h245_hook) nat_h245;
676
677         /* Read h245Address */
678         if (!get_h225_addr(ct, *data, taddr, &addr, &port) ||
679             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
680             port == 0)
681                 return 0;
682
683         /* Create expect for h245 connection */
684         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
685                 return -1;
686         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT,
687                           ct->tuplehash[!dir].tuple.src.l3num,
688                           &ct->tuplehash[!dir].tuple.src.u3,
689                           &ct->tuplehash[!dir].tuple.dst.u3,
690                           IPPROTO_TCP, NULL, &port);
691         exp->helper = &nf_conntrack_helper_h245;
692
693         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
694                    &ct->tuplehash[!dir].tuple.dst.u3,
695                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
696             (nat_h245 = rcu_dereference(nat_h245_hook)) &&
697             ct->status & IPS_NAT_MASK) {
698                 /* NAT needed */
699                 ret = nat_h245(skb, ct, ctinfo, data, dataoff, taddr,
700                                port, exp);
701         } else {                /* Conntrack only */
702                 if (nf_ct_expect_related(exp) == 0) {
703                         pr_debug("nf_ct_q931: expect H.245 ");
704                         NF_CT_DUMP_TUPLE(&exp->tuple);
705                 } else
706                         ret = -1;
707         }
708
709         nf_ct_expect_put(exp);
710
711         return ret;
712 }
713
714 /* If the calling party is on the same side of the forward-to party,
715  * we don't need to track the second call */
716 static int callforward_do_filter(const union nf_inet_addr *src,
717                                  const union nf_inet_addr *dst, int family)
718 {
719         const struct nf_afinfo *afinfo;
720         struct flowi fl1, fl2;
721         int ret = 0;
722
723         /* rcu_read_lock()ed by nf_hook_slow() */
724         afinfo = nf_get_afinfo(family);
725         if (!afinfo)
726                 return 0;
727
728         memset(&fl1, 0, sizeof(fl1));
729         memset(&fl2, 0, sizeof(fl2));
730
731         switch (family) {
732         case AF_INET: {
733                 struct rtable *rt1, *rt2;
734
735                 fl1.fl4_dst = src->ip;
736                 fl2.fl4_dst = dst->ip;
737                 if (!afinfo->route((struct dst_entry **)&rt1, &fl1)) {
738                         if (!afinfo->route((struct dst_entry **)&rt2, &fl2)) {
739                                 if (rt1->rt_gateway == rt2->rt_gateway &&
740                                     rt1->u.dst.dev  == rt2->u.dst.dev)
741                                         ret = 1;
742                                 dst_release(&rt2->u.dst);
743                         }
744                         dst_release(&rt1->u.dst);
745                 }
746                 break;
747         }
748 #if defined(CONFIG_NF_CONNTRACK_IPV6) || \
749     defined(CONFIG_NF_CONNTRACK_IPV6_MODULE)
750         case AF_INET6: {
751                 struct rt6_info *rt1, *rt2;
752
753                 memcpy(&fl1.fl6_dst, src, sizeof(fl1.fl6_dst));
754                 memcpy(&fl2.fl6_dst, dst, sizeof(fl2.fl6_dst));
755                 if (!afinfo->route((struct dst_entry **)&rt1, &fl1)) {
756                         if (!afinfo->route((struct dst_entry **)&rt2, &fl2)) {
757                                 if (!memcmp(&rt1->rt6i_gateway, &rt2->rt6i_gateway,
758                                             sizeof(rt1->rt6i_gateway)) &&
759                                     rt1->u.dst.dev == rt2->u.dst.dev)
760                                         ret = 1;
761                                 dst_release(&rt2->u.dst);
762                         }
763                         dst_release(&rt1->u.dst);
764                 }
765                 break;
766         }
767 #endif
768         }
769         return ret;
770
771 }
772
773 /****************************************************************************/
774 static int expect_callforwarding(struct sk_buff *skb,
775                                  struct nf_conn *ct,
776                                  enum ip_conntrack_info ctinfo,
777                                  unsigned char **data, int dataoff,
778                                  TransportAddress *taddr)
779 {
780         int dir = CTINFO2DIR(ctinfo);
781         int ret = 0;
782         __be16 port;
783         union nf_inet_addr addr;
784         struct nf_conntrack_expect *exp;
785         typeof(nat_callforwarding_hook) nat_callforwarding;
786
787         /* Read alternativeAddress */
788         if (!get_h225_addr(ct, *data, taddr, &addr, &port) || port == 0)
789                 return 0;
790
791         /* If the calling party is on the same side of the forward-to party,
792          * we don't need to track the second call */
793         if (callforward_filter &&
794             callforward_do_filter(&addr, &ct->tuplehash[!dir].tuple.src.u3,
795                                   ct->tuplehash[!dir].tuple.src.l3num)) {
796                 pr_debug("nf_ct_q931: Call Forwarding not tracked\n");
797                 return 0;
798         }
799
800         /* Create expect for the second call leg */
801         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
802                 return -1;
803         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT,
804                           ct->tuplehash[!dir].tuple.src.l3num,
805                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
806                           IPPROTO_TCP, NULL, &port);
807         exp->helper = nf_conntrack_helper_q931;
808
809         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
810                    &ct->tuplehash[!dir].tuple.dst.u3,
811                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
812             (nat_callforwarding = rcu_dereference(nat_callforwarding_hook)) &&
813             ct->status & IPS_NAT_MASK) {
814                 /* Need NAT */
815                 ret = nat_callforwarding(skb, ct, ctinfo, data, dataoff,
816                                          taddr, port, exp);
817         } else {                /* Conntrack only */
818                 if (nf_ct_expect_related(exp) == 0) {
819                         pr_debug("nf_ct_q931: expect Call Forwarding ");
820                         NF_CT_DUMP_TUPLE(&exp->tuple);
821                 } else
822                         ret = -1;
823         }
824
825         nf_ct_expect_put(exp);
826
827         return ret;
828 }
829
830 /****************************************************************************/
831 static int process_setup(struct sk_buff *skb, struct nf_conn *ct,
832                          enum ip_conntrack_info ctinfo,
833                          unsigned char **data, int dataoff,
834                          Setup_UUIE *setup)
835 {
836         int dir = CTINFO2DIR(ctinfo);
837         int ret;
838         int i;
839         __be16 port;
840         union nf_inet_addr addr;
841         typeof(set_h225_addr_hook) set_h225_addr;
842
843         pr_debug("nf_ct_q931: Setup\n");
844
845         if (setup->options & eSetup_UUIE_h245Address) {
846                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
847                                   &setup->h245Address);
848                 if (ret < 0)
849                         return -1;
850         }
851
852         set_h225_addr = rcu_dereference(set_h225_addr_hook);
853         if ((setup->options & eSetup_UUIE_destCallSignalAddress) &&
854             (set_h225_addr) && ct->status & IPS_NAT_MASK &&
855             get_h225_addr(ct, *data, &setup->destCallSignalAddress,
856                           &addr, &port) &&
857             memcmp(&addr, &ct->tuplehash[!dir].tuple.src.u3, sizeof(addr))) {
858                 pr_debug("nf_ct_q931: set destCallSignalAddress "
859                          NIP6_FMT ":%hu->" NIP6_FMT ":%hu\n",
860                          NIP6(*(struct in6_addr *)&addr), ntohs(port),
861                          NIP6(*(struct in6_addr *)&ct->tuplehash[!dir].tuple.src.u3),
862                          ntohs(ct->tuplehash[!dir].tuple.src.u.tcp.port));
863                 ret = set_h225_addr(skb, data, dataoff,
864                                     &setup->destCallSignalAddress,
865                                     &ct->tuplehash[!dir].tuple.src.u3,
866                                     ct->tuplehash[!dir].tuple.src.u.tcp.port);
867                 if (ret < 0)
868                         return -1;
869         }
870
871         if ((setup->options & eSetup_UUIE_sourceCallSignalAddress) &&
872             (set_h225_addr) && ct->status & IPS_NAT_MASK &&
873             get_h225_addr(ct, *data, &setup->sourceCallSignalAddress,
874                           &addr, &port) &&
875             memcmp(&addr, &ct->tuplehash[!dir].tuple.dst.u3, sizeof(addr))) {
876                 pr_debug("nf_ct_q931: set sourceCallSignalAddress "
877                          NIP6_FMT ":%hu->" NIP6_FMT ":%hu\n",
878                          NIP6(*(struct in6_addr *)&addr), ntohs(port),
879                          NIP6(*(struct in6_addr *)&ct->tuplehash[!dir].tuple.dst.u3),
880                          ntohs(ct->tuplehash[!dir].tuple.dst.u.tcp.port));
881                 ret = set_h225_addr(skb, data, dataoff,
882                                     &setup->sourceCallSignalAddress,
883                                     &ct->tuplehash[!dir].tuple.dst.u3,
884                                     ct->tuplehash[!dir].tuple.dst.u.tcp.port);
885                 if (ret < 0)
886                         return -1;
887         }
888
889         if (setup->options & eSetup_UUIE_fastStart) {
890                 for (i = 0; i < setup->fastStart.count; i++) {
891                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
892                                           &setup->fastStart.item[i]);
893                         if (ret < 0)
894                                 return -1;
895                 }
896         }
897
898         return 0;
899 }
900
901 /****************************************************************************/
902 static int process_callproceeding(struct sk_buff *skb,
903                                   struct nf_conn *ct,
904                                   enum ip_conntrack_info ctinfo,
905                                   unsigned char **data, int dataoff,
906                                   CallProceeding_UUIE *callproc)
907 {
908         int ret;
909         int i;
910
911         pr_debug("nf_ct_q931: CallProceeding\n");
912
913         if (callproc->options & eCallProceeding_UUIE_h245Address) {
914                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
915                                   &callproc->h245Address);
916                 if (ret < 0)
917                         return -1;
918         }
919
920         if (callproc->options & eCallProceeding_UUIE_fastStart) {
921                 for (i = 0; i < callproc->fastStart.count; i++) {
922                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
923                                           &callproc->fastStart.item[i]);
924                         if (ret < 0)
925                                 return -1;
926                 }
927         }
928
929         return 0;
930 }
931
932 /****************************************************************************/
933 static int process_connect(struct sk_buff *skb, struct nf_conn *ct,
934                            enum ip_conntrack_info ctinfo,
935                            unsigned char **data, int dataoff,
936                            Connect_UUIE *connect)
937 {
938         int ret;
939         int i;
940
941         pr_debug("nf_ct_q931: Connect\n");
942
943         if (connect->options & eConnect_UUIE_h245Address) {
944                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
945                                   &connect->h245Address);
946                 if (ret < 0)
947                         return -1;
948         }
949
950         if (connect->options & eConnect_UUIE_fastStart) {
951                 for (i = 0; i < connect->fastStart.count; i++) {
952                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
953                                           &connect->fastStart.item[i]);
954                         if (ret < 0)
955                                 return -1;
956                 }
957         }
958
959         return 0;
960 }
961
962 /****************************************************************************/
963 static int process_alerting(struct sk_buff *skb, struct nf_conn *ct,
964                             enum ip_conntrack_info ctinfo,
965                             unsigned char **data, int dataoff,
966                             Alerting_UUIE *alert)
967 {
968         int ret;
969         int i;
970
971         pr_debug("nf_ct_q931: Alerting\n");
972
973         if (alert->options & eAlerting_UUIE_h245Address) {
974                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
975                                   &alert->h245Address);
976                 if (ret < 0)
977                         return -1;
978         }
979
980         if (alert->options & eAlerting_UUIE_fastStart) {
981                 for (i = 0; i < alert->fastStart.count; i++) {
982                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
983                                           &alert->fastStart.item[i]);
984                         if (ret < 0)
985                                 return -1;
986                 }
987         }
988
989         return 0;
990 }
991
992 /****************************************************************************/
993 static int process_facility(struct sk_buff *skb, struct nf_conn *ct,
994                             enum ip_conntrack_info ctinfo,
995                             unsigned char **data, int dataoff,
996                             Facility_UUIE *facility)
997 {
998         int ret;
999         int i;
1000
1001         pr_debug("nf_ct_q931: Facility\n");
1002
1003         if (facility->reason.choice == eFacilityReason_callForwarded) {
1004                 if (facility->options & eFacility_UUIE_alternativeAddress)
1005                         return expect_callforwarding(skb, ct, ctinfo, data,
1006                                                      dataoff,
1007                                                      &facility->
1008                                                      alternativeAddress);
1009                 return 0;
1010         }
1011
1012         if (facility->options & eFacility_UUIE_h245Address) {
1013                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
1014                                   &facility->h245Address);
1015                 if (ret < 0)
1016                         return -1;
1017         }
1018
1019         if (facility->options & eFacility_UUIE_fastStart) {
1020                 for (i = 0; i < facility->fastStart.count; i++) {
1021                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
1022                                           &facility->fastStart.item[i]);
1023                         if (ret < 0)
1024                                 return -1;
1025                 }
1026         }
1027
1028         return 0;
1029 }
1030
1031 /****************************************************************************/
1032 static int process_progress(struct sk_buff *skb, struct nf_conn *ct,
1033                             enum ip_conntrack_info ctinfo,
1034                             unsigned char **data, int dataoff,
1035                             Progress_UUIE *progress)
1036 {
1037         int ret;
1038         int i;
1039
1040         pr_debug("nf_ct_q931: Progress\n");
1041
1042         if (progress->options & eProgress_UUIE_h245Address) {
1043                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
1044                                   &progress->h245Address);
1045                 if (ret < 0)
1046                         return -1;
1047         }
1048
1049         if (progress->options & eProgress_UUIE_fastStart) {
1050                 for (i = 0; i < progress->fastStart.count; i++) {
1051                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
1052                                           &progress->fastStart.item[i]);
1053                         if (ret < 0)
1054                                 return -1;
1055                 }
1056         }
1057
1058         return 0;
1059 }
1060
1061 /****************************************************************************/
1062 static int process_q931(struct sk_buff *skb, struct nf_conn *ct,
1063                         enum ip_conntrack_info ctinfo,
1064                         unsigned char **data, int dataoff, Q931 *q931)
1065 {
1066         H323_UU_PDU *pdu = &q931->UUIE.h323_uu_pdu;
1067         int i;
1068         int ret = 0;
1069
1070         switch (pdu->h323_message_body.choice) {
1071         case eH323_UU_PDU_h323_message_body_setup:
1072                 ret = process_setup(skb, ct, ctinfo, data, dataoff,
1073                                     &pdu->h323_message_body.setup);
1074                 break;
1075         case eH323_UU_PDU_h323_message_body_callProceeding:
1076                 ret = process_callproceeding(skb, ct, ctinfo, data, dataoff,
1077                                              &pdu->h323_message_body.
1078                                              callProceeding);
1079                 break;
1080         case eH323_UU_PDU_h323_message_body_connect:
1081                 ret = process_connect(skb, ct, ctinfo, data, dataoff,
1082                                       &pdu->h323_message_body.connect);
1083                 break;
1084         case eH323_UU_PDU_h323_message_body_alerting:
1085                 ret = process_alerting(skb, ct, ctinfo, data, dataoff,
1086                                        &pdu->h323_message_body.alerting);
1087                 break;
1088         case eH323_UU_PDU_h323_message_body_facility:
1089                 ret = process_facility(skb, ct, ctinfo, data, dataoff,
1090                                        &pdu->h323_message_body.facility);
1091                 break;
1092         case eH323_UU_PDU_h323_message_body_progress:
1093                 ret = process_progress(skb, ct, ctinfo, data, dataoff,
1094                                        &pdu->h323_message_body.progress);
1095                 break;
1096         default:
1097                 pr_debug("nf_ct_q931: Q.931 signal %d\n",
1098                          pdu->h323_message_body.choice);
1099                 break;
1100         }
1101
1102         if (ret < 0)
1103                 return -1;
1104
1105         if (pdu->options & eH323_UU_PDU_h245Control) {
1106                 for (i = 0; i < pdu->h245Control.count; i++) {
1107                         ret = process_h245(skb, ct, ctinfo, data, dataoff,
1108                                            &pdu->h245Control.item[i]);
1109                         if (ret < 0)
1110                                 return -1;
1111                 }
1112         }
1113
1114         return 0;
1115 }
1116
1117 /****************************************************************************/
1118 static int q931_help(struct sk_buff *skb, unsigned int protoff,
1119                      struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1120 {
1121         static Q931 q931;
1122         unsigned char *data = NULL;
1123         int datalen;
1124         int dataoff;
1125         int ret;
1126
1127         /* Until there's been traffic both ways, don't look in packets. */
1128         if (ctinfo != IP_CT_ESTABLISHED &&
1129             ctinfo != IP_CT_ESTABLISHED + IP_CT_IS_REPLY) {
1130                 return NF_ACCEPT;
1131         }
1132         pr_debug("nf_ct_q931: skblen = %u\n", skb->len);
1133
1134         spin_lock_bh(&nf_h323_lock);
1135
1136         /* Process each TPKT */
1137         while (get_tpkt_data(skb, protoff, ct, ctinfo,
1138                              &data, &datalen, &dataoff)) {
1139                 pr_debug("nf_ct_q931: TPKT len=%d ", datalen);
1140                 NF_CT_DUMP_TUPLE(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1141
1142                 /* Decode Q.931 signal */
1143                 ret = DecodeQ931(data, datalen, &q931);
1144                 if (ret < 0) {
1145                         pr_debug("nf_ct_q931: decoding error: %s\n",
1146                                  ret == H323_ERROR_BOUND ?
1147                                  "out of bound" : "out of range");
1148                         /* We don't drop when decoding error */
1149                         break;
1150                 }
1151
1152                 /* Process Q.931 signal */
1153                 if (process_q931(skb, ct, ctinfo, &data, dataoff, &q931) < 0)
1154                         goto drop;
1155         }
1156
1157         spin_unlock_bh(&nf_h323_lock);
1158         return NF_ACCEPT;
1159
1160       drop:
1161         spin_unlock_bh(&nf_h323_lock);
1162         if (net_ratelimit())
1163                 printk("nf_ct_q931: packet dropped\n");
1164         return NF_DROP;
1165 }
1166
1167 /****************************************************************************/
1168 static const struct nf_conntrack_expect_policy q931_exp_policy = {
1169         /* T.120 and H.245 */
1170         .max_expected           = H323_RTP_CHANNEL_MAX * 4 + 4,
1171         .timeout                = 240,
1172 };
1173
1174 static struct nf_conntrack_helper nf_conntrack_helper_q931[] __read_mostly = {
1175         {
1176                 .name                   = "Q.931",
1177                 .me                     = THIS_MODULE,
1178                 .tuple.src.l3num        = AF_INET,
1179                 .tuple.src.u.tcp.port   = __constant_htons(Q931_PORT),
1180                 .tuple.dst.protonum     = IPPROTO_TCP,
1181                 .help                   = q931_help,
1182                 .expect_policy          = &q931_exp_policy,
1183         },
1184         {
1185                 .name                   = "Q.931",
1186                 .me                     = THIS_MODULE,
1187                 .tuple.src.l3num        = AF_INET6,
1188                 .tuple.src.u.tcp.port   = __constant_htons(Q931_PORT),
1189                 .tuple.dst.protonum     = IPPROTO_TCP,
1190                 .help                   = q931_help,
1191                 .expect_policy          = &q931_exp_policy,
1192         },
1193 };
1194
1195 /****************************************************************************/
1196 static unsigned char *get_udp_data(struct sk_buff *skb, unsigned int protoff,
1197                                    int *datalen)
1198 {
1199         const struct udphdr *uh;
1200         struct udphdr _uh;
1201         int dataoff;
1202
1203         uh = skb_header_pointer(skb, protoff, sizeof(_uh), &_uh);
1204         if (uh == NULL)
1205                 return NULL;
1206         dataoff = protoff + sizeof(_uh);
1207         if (dataoff >= skb->len)
1208                 return NULL;
1209         *datalen = skb->len - dataoff;
1210         return skb_header_pointer(skb, dataoff, *datalen, h323_buffer);
1211 }
1212
1213 /****************************************************************************/
1214 static struct nf_conntrack_expect *find_expect(struct nf_conn *ct,
1215                                                union nf_inet_addr *addr,
1216                                                __be16 port)
1217 {
1218         struct nf_conntrack_expect *exp;
1219         struct nf_conntrack_tuple tuple;
1220
1221         memset(&tuple.src.u3, 0, sizeof(tuple.src.u3));
1222         tuple.src.u.tcp.port = 0;
1223         memcpy(&tuple.dst.u3, addr, sizeof(tuple.dst.u3));
1224         tuple.dst.u.tcp.port = port;
1225         tuple.dst.protonum = IPPROTO_TCP;
1226
1227         exp = __nf_ct_expect_find(&tuple);
1228         if (exp && exp->master == ct)
1229                 return exp;
1230         return NULL;
1231 }
1232
1233 /****************************************************************************/
1234 static int set_expect_timeout(struct nf_conntrack_expect *exp,
1235                               unsigned timeout)
1236 {
1237         if (!exp || !del_timer(&exp->timeout))
1238                 return 0;
1239
1240         exp->timeout.expires = jiffies + timeout * HZ;
1241         add_timer(&exp->timeout);
1242
1243         return 1;
1244 }
1245
1246 /****************************************************************************/
1247 static int expect_q931(struct sk_buff *skb, struct nf_conn *ct,
1248                        enum ip_conntrack_info ctinfo,
1249                        unsigned char **data,
1250                        TransportAddress *taddr, int count)
1251 {
1252         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1253         int dir = CTINFO2DIR(ctinfo);
1254         int ret = 0;
1255         int i;
1256         __be16 port;
1257         union nf_inet_addr addr;
1258         struct nf_conntrack_expect *exp;
1259         typeof(nat_q931_hook) nat_q931;
1260
1261         /* Look for the first related address */
1262         for (i = 0; i < count; i++) {
1263                 if (get_h225_addr(ct, *data, &taddr[i], &addr, &port) &&
1264                     memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3,
1265                            sizeof(addr)) == 0 && port != 0)
1266                         break;
1267         }
1268
1269         if (i >= count)         /* Not found */
1270                 return 0;
1271
1272         /* Create expect for Q.931 */
1273         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1274                 return -1;
1275         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT,
1276                           ct->tuplehash[!dir].tuple.src.l3num,
1277                           gkrouted_only ? /* only accept calls from GK? */
1278                                 &ct->tuplehash[!dir].tuple.src.u3 : NULL,
1279                           &ct->tuplehash[!dir].tuple.dst.u3,
1280                           IPPROTO_TCP, NULL, &port);
1281         exp->helper = nf_conntrack_helper_q931;
1282         exp->flags = NF_CT_EXPECT_PERMANENT;    /* Accept multiple calls */
1283
1284         nat_q931 = rcu_dereference(nat_q931_hook);
1285         if (nat_q931 && ct->status & IPS_NAT_MASK) {    /* Need NAT */
1286                 ret = nat_q931(skb, ct, ctinfo, data, taddr, i, port, exp);
1287         } else {                /* Conntrack only */
1288                 if (nf_ct_expect_related(exp) == 0) {
1289                         pr_debug("nf_ct_ras: expect Q.931 ");
1290                         NF_CT_DUMP_TUPLE(&exp->tuple);
1291
1292                         /* Save port for looking up expect in processing RCF */
1293                         info->sig_port[dir] = port;
1294                 } else
1295                         ret = -1;
1296         }
1297
1298         nf_ct_expect_put(exp);
1299
1300         return ret;
1301 }
1302
1303 /****************************************************************************/
1304 static int process_grq(struct sk_buff *skb, struct nf_conn *ct,
1305                        enum ip_conntrack_info ctinfo,
1306                        unsigned char **data, GatekeeperRequest *grq)
1307 {
1308         typeof(set_ras_addr_hook) set_ras_addr;
1309
1310         pr_debug("nf_ct_ras: GRQ\n");
1311
1312         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1313         if (set_ras_addr && ct->status & IPS_NAT_MASK)  /* NATed */
1314                 return set_ras_addr(skb, ct, ctinfo, data,
1315                                     &grq->rasAddress, 1);
1316         return 0;
1317 }
1318
1319 /****************************************************************************/
1320 static int process_gcf(struct sk_buff *skb, struct nf_conn *ct,
1321                        enum ip_conntrack_info ctinfo,
1322                        unsigned char **data, GatekeeperConfirm *gcf)
1323 {
1324         int dir = CTINFO2DIR(ctinfo);
1325         int ret = 0;
1326         __be16 port;
1327         union nf_inet_addr addr;
1328         struct nf_conntrack_expect *exp;
1329
1330         pr_debug("nf_ct_ras: GCF\n");
1331
1332         if (!get_h225_addr(ct, *data, &gcf->rasAddress, &addr, &port))
1333                 return 0;
1334
1335         /* Registration port is the same as discovery port */
1336         if (!memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1337             port == ct->tuplehash[dir].tuple.src.u.udp.port)
1338                 return 0;
1339
1340         /* Avoid RAS expectation loops. A GCF is never expected. */
1341         if (test_bit(IPS_EXPECTED_BIT, &ct->status))
1342                 return 0;
1343
1344         /* Need new expect */
1345         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1346                 return -1;
1347         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT,
1348                           ct->tuplehash[!dir].tuple.src.l3num,
1349                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1350                           IPPROTO_UDP, NULL, &port);
1351         exp->helper = nf_conntrack_helper_ras;
1352
1353         if (nf_ct_expect_related(exp) == 0) {
1354                 pr_debug("nf_ct_ras: expect RAS ");
1355                 NF_CT_DUMP_TUPLE(&exp->tuple);
1356         } else
1357                 ret = -1;
1358
1359         nf_ct_expect_put(exp);
1360
1361         return ret;
1362 }
1363
1364 /****************************************************************************/
1365 static int process_rrq(struct sk_buff *skb, struct nf_conn *ct,
1366                        enum ip_conntrack_info ctinfo,
1367                        unsigned char **data, RegistrationRequest *rrq)
1368 {
1369         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1370         int ret;
1371         typeof(set_ras_addr_hook) set_ras_addr;
1372
1373         pr_debug("nf_ct_ras: RRQ\n");
1374
1375         ret = expect_q931(skb, ct, ctinfo, data,
1376                           rrq->callSignalAddress.item,
1377                           rrq->callSignalAddress.count);
1378         if (ret < 0)
1379                 return -1;
1380
1381         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1382         if (set_ras_addr && ct->status & IPS_NAT_MASK) {
1383                 ret = set_ras_addr(skb, ct, ctinfo, data,
1384                                    rrq->rasAddress.item,
1385                                    rrq->rasAddress.count);
1386                 if (ret < 0)
1387                         return -1;
1388         }
1389
1390         if (rrq->options & eRegistrationRequest_timeToLive) {
1391                 pr_debug("nf_ct_ras: RRQ TTL = %u seconds\n", rrq->timeToLive);
1392                 info->timeout = rrq->timeToLive;
1393         } else
1394                 info->timeout = default_rrq_ttl;
1395
1396         return 0;
1397 }
1398
1399 /****************************************************************************/
1400 static int process_rcf(struct sk_buff *skb, struct nf_conn *ct,
1401                        enum ip_conntrack_info ctinfo,
1402                        unsigned char **data, RegistrationConfirm *rcf)
1403 {
1404         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1405         int dir = CTINFO2DIR(ctinfo);
1406         int ret;
1407         struct nf_conntrack_expect *exp;
1408         typeof(set_sig_addr_hook) set_sig_addr;
1409
1410         pr_debug("nf_ct_ras: RCF\n");
1411
1412         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1413         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1414                 ret = set_sig_addr(skb, ct, ctinfo, data,
1415                                         rcf->callSignalAddress.item,
1416                                         rcf->callSignalAddress.count);
1417                 if (ret < 0)
1418                         return -1;
1419         }
1420
1421         if (rcf->options & eRegistrationConfirm_timeToLive) {
1422                 pr_debug("nf_ct_ras: RCF TTL = %u seconds\n", rcf->timeToLive);
1423                 info->timeout = rcf->timeToLive;
1424         }
1425
1426         if (info->timeout > 0) {
1427                 pr_debug("nf_ct_ras: set RAS connection timeout to "
1428                          "%u seconds\n", info->timeout);
1429                 nf_ct_refresh(ct, skb, info->timeout * HZ);
1430
1431                 /* Set expect timeout */
1432                 spin_lock_bh(&nf_conntrack_lock);
1433                 exp = find_expect(ct, &ct->tuplehash[dir].tuple.dst.u3,
1434                                   info->sig_port[!dir]);
1435                 if (exp) {
1436                         pr_debug("nf_ct_ras: set Q.931 expect "
1437                                  "timeout to %u seconds for",
1438                                  info->timeout);
1439                         NF_CT_DUMP_TUPLE(&exp->tuple);
1440                         set_expect_timeout(exp, info->timeout);
1441                 }
1442                 spin_unlock_bh(&nf_conntrack_lock);
1443         }
1444
1445         return 0;
1446 }
1447
1448 /****************************************************************************/
1449 static int process_urq(struct sk_buff *skb, struct nf_conn *ct,
1450                        enum ip_conntrack_info ctinfo,
1451                        unsigned char **data, UnregistrationRequest *urq)
1452 {
1453         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1454         int dir = CTINFO2DIR(ctinfo);
1455         int ret;
1456         typeof(set_sig_addr_hook) set_sig_addr;
1457
1458         pr_debug("nf_ct_ras: URQ\n");
1459
1460         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1461         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1462                 ret = set_sig_addr(skb, ct, ctinfo, data,
1463                                    urq->callSignalAddress.item,
1464                                    urq->callSignalAddress.count);
1465                 if (ret < 0)
1466                         return -1;
1467         }
1468
1469         /* Clear old expect */
1470         nf_ct_remove_expectations(ct);
1471         info->sig_port[dir] = 0;
1472         info->sig_port[!dir] = 0;
1473
1474         /* Give it 30 seconds for UCF or URJ */
1475         nf_ct_refresh(ct, skb, 30 * HZ);
1476
1477         return 0;
1478 }
1479
1480 /****************************************************************************/
1481 static int process_arq(struct sk_buff *skb, struct nf_conn *ct,
1482                        enum ip_conntrack_info ctinfo,
1483                        unsigned char **data, AdmissionRequest *arq)
1484 {
1485         const struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1486         int dir = CTINFO2DIR(ctinfo);
1487         __be16 port;
1488         union nf_inet_addr addr;
1489         typeof(set_h225_addr_hook) set_h225_addr;
1490
1491         pr_debug("nf_ct_ras: ARQ\n");
1492
1493         set_h225_addr = rcu_dereference(set_h225_addr_hook);
1494         if ((arq->options & eAdmissionRequest_destCallSignalAddress) &&
1495             get_h225_addr(ct, *data, &arq->destCallSignalAddress,
1496                           &addr, &port) &&
1497             !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1498             port == info->sig_port[dir] &&
1499             set_h225_addr && ct->status & IPS_NAT_MASK) {
1500                 /* Answering ARQ */
1501                 return set_h225_addr(skb, data, 0,
1502                                      &arq->destCallSignalAddress,
1503                                      &ct->tuplehash[!dir].tuple.dst.u3,
1504                                      info->sig_port[!dir]);
1505         }
1506
1507         if ((arq->options & eAdmissionRequest_srcCallSignalAddress) &&
1508             get_h225_addr(ct, *data, &arq->srcCallSignalAddress,
1509                           &addr, &port) &&
1510             !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1511             set_h225_addr && ct->status & IPS_NAT_MASK) {
1512                 /* Calling ARQ */
1513                 return set_h225_addr(skb, data, 0,
1514                                      &arq->srcCallSignalAddress,
1515                                      &ct->tuplehash[!dir].tuple.dst.u3,
1516                                      port);
1517         }
1518
1519         return 0;
1520 }
1521
1522 /****************************************************************************/
1523 static int process_acf(struct sk_buff *skb, struct nf_conn *ct,
1524                        enum ip_conntrack_info ctinfo,
1525                        unsigned char **data, AdmissionConfirm *acf)
1526 {
1527         int dir = CTINFO2DIR(ctinfo);
1528         int ret = 0;
1529         __be16 port;
1530         union nf_inet_addr addr;
1531         struct nf_conntrack_expect *exp;
1532         typeof(set_sig_addr_hook) set_sig_addr;
1533
1534         pr_debug("nf_ct_ras: ACF\n");
1535
1536         if (!get_h225_addr(ct, *data, &acf->destCallSignalAddress,
1537                            &addr, &port))
1538                 return 0;
1539
1540         if (!memcmp(&addr, &ct->tuplehash[dir].tuple.dst.u3, sizeof(addr))) {
1541                 /* Answering ACF */
1542                 set_sig_addr = rcu_dereference(set_sig_addr_hook);
1543                 if (set_sig_addr && ct->status & IPS_NAT_MASK)
1544                         return set_sig_addr(skb, ct, ctinfo, data,
1545                                             &acf->destCallSignalAddress, 1);
1546                 return 0;
1547         }
1548
1549         /* Need new expect */
1550         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1551                 return -1;
1552         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT,
1553                           ct->tuplehash[!dir].tuple.src.l3num,
1554                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1555                           IPPROTO_TCP, NULL, &port);
1556         exp->flags = NF_CT_EXPECT_PERMANENT;
1557         exp->helper = nf_conntrack_helper_q931;
1558
1559         if (nf_ct_expect_related(exp) == 0) {
1560                 pr_debug("nf_ct_ras: expect Q.931 ");
1561                 NF_CT_DUMP_TUPLE(&exp->tuple);
1562         } else
1563                 ret = -1;
1564
1565         nf_ct_expect_put(exp);
1566
1567         return ret;
1568 }
1569
1570 /****************************************************************************/
1571 static int process_lrq(struct sk_buff *skb, struct nf_conn *ct,
1572                        enum ip_conntrack_info ctinfo,
1573                        unsigned char **data, LocationRequest *lrq)
1574 {
1575         typeof(set_ras_addr_hook) set_ras_addr;
1576
1577         pr_debug("nf_ct_ras: LRQ\n");
1578
1579         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1580         if (set_ras_addr && ct->status & IPS_NAT_MASK)
1581                 return set_ras_addr(skb, ct, ctinfo, data,
1582                                     &lrq->replyAddress, 1);
1583         return 0;
1584 }
1585
1586 /****************************************************************************/
1587 static int process_lcf(struct sk_buff *skb, struct nf_conn *ct,
1588                        enum ip_conntrack_info ctinfo,
1589                        unsigned char **data, LocationConfirm *lcf)
1590 {
1591         int dir = CTINFO2DIR(ctinfo);
1592         int ret = 0;
1593         __be16 port;
1594         union nf_inet_addr addr;
1595         struct nf_conntrack_expect *exp;
1596
1597         pr_debug("nf_ct_ras: LCF\n");
1598
1599         if (!get_h225_addr(ct, *data, &lcf->callSignalAddress,
1600                            &addr, &port))
1601                 return 0;
1602
1603         /* Need new expect for call signal */
1604         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1605                 return -1;
1606         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT,
1607                           ct->tuplehash[!dir].tuple.src.l3num,
1608                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1609                           IPPROTO_TCP, NULL, &port);
1610         exp->flags = NF_CT_EXPECT_PERMANENT;
1611         exp->helper = nf_conntrack_helper_q931;
1612
1613         if (nf_ct_expect_related(exp) == 0) {
1614                 pr_debug("nf_ct_ras: expect Q.931 ");
1615                 NF_CT_DUMP_TUPLE(&exp->tuple);
1616         } else
1617                 ret = -1;
1618
1619         nf_ct_expect_put(exp);
1620
1621         /* Ignore rasAddress */
1622
1623         return ret;
1624 }
1625
1626 /****************************************************************************/
1627 static int process_irr(struct sk_buff *skb, struct nf_conn *ct,
1628                        enum ip_conntrack_info ctinfo,
1629                        unsigned char **data, InfoRequestResponse *irr)
1630 {
1631         int ret;
1632         typeof(set_ras_addr_hook) set_ras_addr;
1633         typeof(set_sig_addr_hook) set_sig_addr;
1634
1635         pr_debug("nf_ct_ras: IRR\n");
1636
1637         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1638         if (set_ras_addr && ct->status & IPS_NAT_MASK) {
1639                 ret = set_ras_addr(skb, ct, ctinfo, data,
1640                                    &irr->rasAddress, 1);
1641                 if (ret < 0)
1642                         return -1;
1643         }
1644
1645         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1646         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1647                 ret = set_sig_addr(skb, ct, ctinfo, data,
1648                                         irr->callSignalAddress.item,
1649                                         irr->callSignalAddress.count);
1650                 if (ret < 0)
1651                         return -1;
1652         }
1653
1654         return 0;
1655 }
1656
1657 /****************************************************************************/
1658 static int process_ras(struct sk_buff *skb, struct nf_conn *ct,
1659                        enum ip_conntrack_info ctinfo,
1660                        unsigned char **data, RasMessage *ras)
1661 {
1662         switch (ras->choice) {
1663         case eRasMessage_gatekeeperRequest:
1664                 return process_grq(skb, ct, ctinfo, data,
1665                                    &ras->gatekeeperRequest);
1666         case eRasMessage_gatekeeperConfirm:
1667                 return process_gcf(skb, ct, ctinfo, data,
1668                                    &ras->gatekeeperConfirm);
1669         case eRasMessage_registrationRequest:
1670                 return process_rrq(skb, ct, ctinfo, data,
1671                                    &ras->registrationRequest);
1672         case eRasMessage_registrationConfirm:
1673                 return process_rcf(skb, ct, ctinfo, data,
1674                                    &ras->registrationConfirm);
1675         case eRasMessage_unregistrationRequest:
1676                 return process_urq(skb, ct, ctinfo, data,
1677                                    &ras->unregistrationRequest);
1678         case eRasMessage_admissionRequest:
1679                 return process_arq(skb, ct, ctinfo, data,
1680                                    &ras->admissionRequest);
1681         case eRasMessage_admissionConfirm:
1682                 return process_acf(skb, ct, ctinfo, data,
1683                                    &ras->admissionConfirm);
1684         case eRasMessage_locationRequest:
1685                 return process_lrq(skb, ct, ctinfo, data,
1686                                    &ras->locationRequest);
1687         case eRasMessage_locationConfirm:
1688                 return process_lcf(skb, ct, ctinfo, data,
1689                                    &ras->locationConfirm);
1690         case eRasMessage_infoRequestResponse:
1691                 return process_irr(skb, ct, ctinfo, data,
1692                                    &ras->infoRequestResponse);
1693         default:
1694                 pr_debug("nf_ct_ras: RAS message %d\n", ras->choice);
1695                 break;
1696         }
1697
1698         return 0;
1699 }
1700
1701 /****************************************************************************/
1702 static int ras_help(struct sk_buff *skb, unsigned int protoff,
1703                     struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1704 {
1705         static RasMessage ras;
1706         unsigned char *data;
1707         int datalen = 0;
1708         int ret;
1709
1710         pr_debug("nf_ct_ras: skblen = %u\n", skb->len);
1711
1712         spin_lock_bh(&nf_h323_lock);
1713
1714         /* Get UDP data */
1715         data = get_udp_data(skb, protoff, &datalen);
1716         if (data == NULL)
1717                 goto accept;
1718         pr_debug("nf_ct_ras: RAS message len=%d ", datalen);
1719         NF_CT_DUMP_TUPLE(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1720
1721         /* Decode RAS message */
1722         ret = DecodeRasMessage(data, datalen, &ras);
1723         if (ret < 0) {
1724                 pr_debug("nf_ct_ras: decoding error: %s\n",
1725                          ret == H323_ERROR_BOUND ?
1726                          "out of bound" : "out of range");
1727                 goto accept;
1728         }
1729
1730         /* Process RAS message */
1731         if (process_ras(skb, ct, ctinfo, &data, &ras) < 0)
1732                 goto drop;
1733
1734       accept:
1735         spin_unlock_bh(&nf_h323_lock);
1736         return NF_ACCEPT;
1737
1738       drop:
1739         spin_unlock_bh(&nf_h323_lock);
1740         if (net_ratelimit())
1741                 printk("nf_ct_ras: packet dropped\n");
1742         return NF_DROP;
1743 }
1744
1745 /****************************************************************************/
1746 static const struct nf_conntrack_expect_policy ras_exp_policy = {
1747         .max_expected           = 32,
1748         .timeout                = 240,
1749 };
1750
1751 static struct nf_conntrack_helper nf_conntrack_helper_ras[] __read_mostly = {
1752         {
1753                 .name                   = "RAS",
1754                 .me                     = THIS_MODULE,
1755                 .tuple.src.l3num        = AF_INET,
1756                 .tuple.src.u.udp.port   = __constant_htons(RAS_PORT),
1757                 .tuple.dst.protonum     = IPPROTO_UDP,
1758                 .help                   = ras_help,
1759                 .expect_policy          = &ras_exp_policy,
1760         },
1761         {
1762                 .name                   = "RAS",
1763                 .me                     = THIS_MODULE,
1764                 .tuple.src.l3num        = AF_INET6,
1765                 .tuple.src.u.udp.port   = __constant_htons(RAS_PORT),
1766                 .tuple.dst.protonum     = IPPROTO_UDP,
1767                 .help                   = ras_help,
1768                 .expect_policy          = &ras_exp_policy,
1769         },
1770 };
1771
1772 /****************************************************************************/
1773 static void __exit nf_conntrack_h323_fini(void)
1774 {
1775         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[1]);
1776         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1777         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1778         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1779         kfree(h323_buffer);
1780         pr_debug("nf_ct_h323: fini\n");
1781 }
1782
1783 /****************************************************************************/
1784 static int __init nf_conntrack_h323_init(void)
1785 {
1786         int ret;
1787
1788         h323_buffer = kmalloc(65536, GFP_KERNEL);
1789         if (!h323_buffer)
1790                 return -ENOMEM;
1791         ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[0]);
1792         if (ret < 0)
1793                 goto err1;
1794         ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[1]);
1795         if (ret < 0)
1796                 goto err2;
1797         ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[0]);
1798         if (ret < 0)
1799                 goto err3;
1800         ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[1]);
1801         if (ret < 0)
1802                 goto err4;
1803         pr_debug("nf_ct_h323: init success\n");
1804         return 0;
1805
1806 err4:
1807         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1808 err3:
1809         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1810 err2:
1811         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1812 err1:
1813         return ret;
1814 }
1815
1816 /****************************************************************************/
1817 module_init(nf_conntrack_h323_init);
1818 module_exit(nf_conntrack_h323_fini);
1819
1820 EXPORT_SYMBOL_GPL(get_h225_addr);
1821 EXPORT_SYMBOL_GPL(set_h245_addr_hook);
1822 EXPORT_SYMBOL_GPL(set_h225_addr_hook);
1823 EXPORT_SYMBOL_GPL(set_sig_addr_hook);
1824 EXPORT_SYMBOL_GPL(set_ras_addr_hook);
1825 EXPORT_SYMBOL_GPL(nat_rtp_rtcp_hook);
1826 EXPORT_SYMBOL_GPL(nat_t120_hook);
1827 EXPORT_SYMBOL_GPL(nat_h245_hook);
1828 EXPORT_SYMBOL_GPL(nat_callforwarding_hook);
1829 EXPORT_SYMBOL_GPL(nat_q931_hook);
1830
1831 MODULE_AUTHOR("Jing Min Zhao <zhaojingmin@users.sourceforge.net>");
1832 MODULE_DESCRIPTION("H.323 connection tracking helper");
1833 MODULE_LICENSE("GPL");
1834 MODULE_ALIAS("ip_conntrack_h323");