netfilter: nf_conntrack: fix rt_gateway checks for H.323 helper
[opensuse:kernel.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/slab.h>
21 #include <linux/udp.h>
22 #include <linux/tcp.h>
23 #include <linux/skbuff.h>
24 #include <net/route.h>
25 #include <net/ip6_route.h>
26
27 #include <net/netfilter/nf_conntrack.h>
28 #include <net/netfilter/nf_conntrack_core.h>
29 #include <net/netfilter/nf_conntrack_tuple.h>
30 #include <net/netfilter/nf_conntrack_expect.h>
31 #include <net/netfilter/nf_conntrack_ecache.h>
32 #include <net/netfilter/nf_conntrack_helper.h>
33 #include <net/netfilter/nf_conntrack_zones.h>
34 #include <linux/netfilter/nf_conntrack_h323.h>
35
36 /* Parameters */
37 static unsigned int default_rrq_ttl __read_mostly = 300;
38 module_param(default_rrq_ttl, uint, 0600);
39 MODULE_PARM_DESC(default_rrq_ttl, "use this TTL if it's missing in RRQ");
40
41 static int gkrouted_only __read_mostly = 1;
42 module_param(gkrouted_only, int, 0600);
43 MODULE_PARM_DESC(gkrouted_only, "only accept calls from gatekeeper");
44
45 static bool callforward_filter __read_mostly = true;
46 module_param(callforward_filter, bool, 0600);
47 MODULE_PARM_DESC(callforward_filter, "only create call forwarding expectations "
48                                      "if both endpoints are on different sides "
49                                      "(determined by routing information)");
50
51 /* Hooks for NAT */
52 int (*set_h245_addr_hook) (struct sk_buff *skb,
53                            unsigned char **data, int dataoff,
54                            H245_TransportAddress *taddr,
55                            union nf_inet_addr *addr, __be16 port)
56                            __read_mostly;
57 int (*set_h225_addr_hook) (struct sk_buff *skb,
58                            unsigned char **data, int dataoff,
59                            TransportAddress *taddr,
60                            union nf_inet_addr *addr, __be16 port)
61                            __read_mostly;
62 int (*set_sig_addr_hook) (struct sk_buff *skb,
63                           struct nf_conn *ct,
64                           enum ip_conntrack_info ctinfo,
65                           unsigned char **data,
66                           TransportAddress *taddr, int count) __read_mostly;
67 int (*set_ras_addr_hook) (struct sk_buff *skb,
68                           struct nf_conn *ct,
69                           enum ip_conntrack_info ctinfo,
70                           unsigned char **data,
71                           TransportAddress *taddr, int count) __read_mostly;
72 int (*nat_rtp_rtcp_hook) (struct sk_buff *skb,
73                           struct nf_conn *ct,
74                           enum ip_conntrack_info ctinfo,
75                           unsigned char **data, int dataoff,
76                           H245_TransportAddress *taddr,
77                           __be16 port, __be16 rtp_port,
78                           struct nf_conntrack_expect *rtp_exp,
79                           struct nf_conntrack_expect *rtcp_exp) __read_mostly;
80 int (*nat_t120_hook) (struct sk_buff *skb,
81                       struct nf_conn *ct,
82                       enum ip_conntrack_info ctinfo,
83                       unsigned char **data, int dataoff,
84                       H245_TransportAddress *taddr, __be16 port,
85                       struct nf_conntrack_expect *exp) __read_mostly;
86 int (*nat_h245_hook) (struct sk_buff *skb,
87                       struct nf_conn *ct,
88                       enum ip_conntrack_info ctinfo,
89                       unsigned char **data, int dataoff,
90                       TransportAddress *taddr, __be16 port,
91                       struct nf_conntrack_expect *exp) __read_mostly;
92 int (*nat_callforwarding_hook) (struct sk_buff *skb,
93                                 struct nf_conn *ct,
94                                 enum ip_conntrack_info ctinfo,
95                                 unsigned char **data, int dataoff,
96                                 TransportAddress *taddr, __be16 port,
97                                 struct nf_conntrack_expect *exp) __read_mostly;
98 int (*nat_q931_hook) (struct sk_buff *skb,
99                       struct nf_conn *ct,
100                       enum ip_conntrack_info ctinfo,
101                       unsigned char **data, TransportAddress *taddr, int idx,
102                       __be16 port, struct nf_conntrack_expect *exp)
103                       __read_mostly;
104
105 static DEFINE_SPINLOCK(nf_h323_lock);
106 static char *h323_buffer;
107
108 static struct nf_conntrack_helper nf_conntrack_helper_h245;
109 static struct nf_conntrack_helper nf_conntrack_helper_q931[];
110 static struct nf_conntrack_helper nf_conntrack_helper_ras[];
111
112 /****************************************************************************/
113 static int get_tpkt_data(struct sk_buff *skb, unsigned int protoff,
114                          struct nf_conn *ct, enum ip_conntrack_info ctinfo,
115                          unsigned char **data, int *datalen, int *dataoff)
116 {
117         struct nf_ct_h323_master *info = nfct_help_data(ct);
118         int dir = CTINFO2DIR(ctinfo);
119         const struct tcphdr *th;
120         struct tcphdr _tcph;
121         int tcpdatalen;
122         int tcpdataoff;
123         unsigned char *tpkt;
124         int tpktlen;
125         int tpktoff;
126
127         /* Get TCP header */
128         th = skb_header_pointer(skb, protoff, sizeof(_tcph), &_tcph);
129         if (th == NULL)
130                 return 0;
131
132         /* Get TCP data offset */
133         tcpdataoff = protoff + th->doff * 4;
134
135         /* Get TCP data length */
136         tcpdatalen = skb->len - tcpdataoff;
137         if (tcpdatalen <= 0)    /* No TCP data */
138                 goto clear_out;
139
140         if (*data == NULL) {    /* first TPKT */
141                 /* Get first TPKT pointer */
142                 tpkt = skb_header_pointer(skb, tcpdataoff, tcpdatalen,
143                                           h323_buffer);
144                 BUG_ON(tpkt == NULL);
145
146                 /* Validate TPKT identifier */
147                 if (tcpdatalen < 4 || tpkt[0] != 0x03 || tpkt[1] != 0) {
148                         /* Netmeeting sends TPKT header and data separately */
149                         if (info->tpkt_len[dir] > 0) {
150                                 pr_debug("nf_ct_h323: previous packet "
151                                          "indicated separate TPKT data of %hu "
152                                          "bytes\n", info->tpkt_len[dir]);
153                                 if (info->tpkt_len[dir] <= tcpdatalen) {
154                                         /* Yes, there was a TPKT header
155                                          * received */
156                                         *data = tpkt;
157                                         *datalen = info->tpkt_len[dir];
158                                         *dataoff = 0;
159                                         goto out;
160                                 }
161
162                                 /* Fragmented TPKT */
163                                 pr_debug("nf_ct_h323: fragmented TPKT\n");
164                                 goto clear_out;
165                         }
166
167                         /* It is not even a TPKT */
168                         return 0;
169                 }
170                 tpktoff = 0;
171         } else {                /* Next TPKT */
172                 tpktoff = *dataoff + *datalen;
173                 tcpdatalen -= tpktoff;
174                 if (tcpdatalen <= 4)    /* No more TPKT */
175                         goto clear_out;
176                 tpkt = *data + *datalen;
177
178                 /* Validate TPKT identifier */
179                 if (tpkt[0] != 0x03 || tpkt[1] != 0)
180                         goto clear_out;
181         }
182
183         /* Validate TPKT length */
184         tpktlen = tpkt[2] * 256 + tpkt[3];
185         if (tpktlen < 4)
186                 goto clear_out;
187         if (tpktlen > tcpdatalen) {
188                 if (tcpdatalen == 4) {  /* Separate TPKT header */
189                         /* Netmeeting sends TPKT header and data separately */
190                         pr_debug("nf_ct_h323: separate TPKT header indicates "
191                                  "there will be TPKT data of %hu bytes\n",
192                                  tpktlen - 4);
193                         info->tpkt_len[dir] = tpktlen - 4;
194                         return 0;
195                 }
196
197                 pr_debug("nf_ct_h323: incomplete TPKT (fragmented?)\n");
198                 goto clear_out;
199         }
200
201         /* This is the encapsulated data */
202         *data = tpkt + 4;
203         *datalen = tpktlen - 4;
204         *dataoff = tpktoff + 4;
205
206       out:
207         /* Clear TPKT length */
208         info->tpkt_len[dir] = 0;
209         return 1;
210
211       clear_out:
212         info->tpkt_len[dir] = 0;
213         return 0;
214 }
215
216 /****************************************************************************/
217 static int get_h245_addr(struct nf_conn *ct, const unsigned char *data,
218                          H245_TransportAddress *taddr,
219                          union nf_inet_addr *addr, __be16 *port)
220 {
221         const unsigned char *p;
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 (nf_ct_l3num(ct) != AF_INET)
230                         return 0;
231                 p = data + taddr->unicastAddress.iPAddress.network;
232                 len = 4;
233                 break;
234         case eUnicastAddress_iP6Address:
235                 if (nf_ct_l3num(ct) != 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         rtp_port = port & ~htons(1);
274         rtcp_port = port | htons(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 /****************************************************************************/
324 static 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 /****************************************************************************/
374 static 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 /****************************************************************************/
403 static 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 /****************************************************************************/
462 static 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 /****************************************************************************/
529 static 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 /****************************************************************************/
563 static 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 && ctinfo != IP_CT_ESTABLISHED_REPLY)
574                 return NF_ACCEPT;
575
576         pr_debug("nf_ct_h245: skblen = %u\n", skb->len);
577
578         spin_lock_bh(&nf_h323_lock);
579
580         /* Process each TPKT */
581         while (get_tpkt_data(skb, protoff, ct, ctinfo,
582                              &data, &datalen, &dataoff)) {
583                 pr_debug("nf_ct_h245: TPKT len=%d ", datalen);
584                 nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
585
586                 /* Decode H.245 signal */
587                 ret = DecodeMultimediaSystemControlMessage(data, datalen,
588                                                            &mscm);
589                 if (ret < 0) {
590                         pr_debug("nf_ct_h245: decoding error: %s\n",
591                                  ret == H323_ERROR_BOUND ?
592                                  "out of bound" : "out of range");
593                         /* We don't drop when decoding error */
594                         break;
595                 }
596
597                 /* Process H.245 signal */
598                 if (process_h245(skb, ct, ctinfo, &data, dataoff, &mscm) < 0)
599                         goto drop;
600         }
601
602         spin_unlock_bh(&nf_h323_lock);
603         return NF_ACCEPT;
604
605       drop:
606         spin_unlock_bh(&nf_h323_lock);
607         net_info_ratelimited("nf_ct_h245: packet dropped\n");
608         return NF_DROP;
609 }
610
611 /****************************************************************************/
612 static const struct nf_conntrack_expect_policy h245_exp_policy = {
613         .max_expected   = H323_RTP_CHANNEL_MAX * 4 + 2 /* T.120 */,
614         .timeout        = 240,
615 };
616
617 static struct nf_conntrack_helper nf_conntrack_helper_h245 __read_mostly = {
618         .name                   = "H.245",
619         .me                     = THIS_MODULE,
620         .data_len               = sizeof(struct nf_ct_h323_master),
621         .tuple.src.l3num        = AF_UNSPEC,
622         .tuple.dst.protonum     = IPPROTO_UDP,
623         .help                   = h245_help,
624         .expect_policy          = &h245_exp_policy,
625 };
626
627 /****************************************************************************/
628 int get_h225_addr(struct nf_conn *ct, unsigned char *data,
629                   TransportAddress *taddr,
630                   union nf_inet_addr *addr, __be16 *port)
631 {
632         const unsigned char *p;
633         int len;
634
635         switch (taddr->choice) {
636         case eTransportAddress_ipAddress:
637                 if (nf_ct_l3num(ct) != AF_INET)
638                         return 0;
639                 p = data + taddr->ipAddress.ip;
640                 len = 4;
641                 break;
642         case eTransportAddress_ip6Address:
643                 if (nf_ct_l3num(ct) != AF_INET6)
644                         return 0;
645                 p = data + taddr->ip6Address.ip;
646                 len = 16;
647                 break;
648         default:
649                 return 0;
650         }
651
652         memcpy(addr, p, len);
653         memset((void *)addr + len, 0, sizeof(*addr) - len);
654         memcpy(port, p + len, sizeof(__be16));
655
656         return 1;
657 }
658
659 /****************************************************************************/
660 static int expect_h245(struct sk_buff *skb, struct nf_conn *ct,
661                        enum ip_conntrack_info ctinfo,
662                        unsigned char **data, int dataoff,
663                        TransportAddress *taddr)
664 {
665         int dir = CTINFO2DIR(ctinfo);
666         int ret = 0;
667         __be16 port;
668         union nf_inet_addr addr;
669         struct nf_conntrack_expect *exp;
670         typeof(nat_h245_hook) nat_h245;
671
672         /* Read h245Address */
673         if (!get_h225_addr(ct, *data, taddr, &addr, &port) ||
674             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
675             port == 0)
676                 return 0;
677
678         /* Create expect for h245 connection */
679         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
680                 return -1;
681         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
682                           &ct->tuplehash[!dir].tuple.src.u3,
683                           &ct->tuplehash[!dir].tuple.dst.u3,
684                           IPPROTO_TCP, NULL, &port);
685         exp->helper = &nf_conntrack_helper_h245;
686
687         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
688                    &ct->tuplehash[!dir].tuple.dst.u3,
689                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
690             (nat_h245 = rcu_dereference(nat_h245_hook)) &&
691             ct->status & IPS_NAT_MASK) {
692                 /* NAT needed */
693                 ret = nat_h245(skb, ct, ctinfo, data, dataoff, taddr,
694                                port, exp);
695         } else {                /* Conntrack only */
696                 if (nf_ct_expect_related(exp) == 0) {
697                         pr_debug("nf_ct_q931: expect H.245 ");
698                         nf_ct_dump_tuple(&exp->tuple);
699                 } else
700                         ret = -1;
701         }
702
703         nf_ct_expect_put(exp);
704
705         return ret;
706 }
707
708 /* If the calling party is on the same side of the forward-to party,
709  * we don't need to track the second call */
710 static int callforward_do_filter(const union nf_inet_addr *src,
711                                  const union nf_inet_addr *dst,
712                                  u_int8_t family)
713 {
714         const struct nf_afinfo *afinfo;
715         int ret = 0;
716
717         /* rcu_read_lock()ed by nf_hook_slow() */
718         afinfo = nf_get_afinfo(family);
719         if (!afinfo)
720                 return 0;
721
722         switch (family) {
723         case AF_INET: {
724                 struct flowi4 fl1, fl2;
725                 struct rtable *rt1, *rt2;
726
727                 memset(&fl1, 0, sizeof(fl1));
728                 fl1.daddr = src->ip;
729
730                 memset(&fl2, 0, sizeof(fl2));
731                 fl2.daddr = dst->ip;
732                 if (!afinfo->route(&init_net, (struct dst_entry **)&rt1,
733                                    flowi4_to_flowi(&fl1), false)) {
734                         if (!afinfo->route(&init_net, (struct dst_entry **)&rt2,
735                                            flowi4_to_flowi(&fl2), false)) {
736                                 if (rt_nexthop(rt1, fl1.daddr) ==
737                                     rt_nexthop(rt2, fl2.daddr) &&
738                                     rt1->dst.dev  == rt2->dst.dev)
739                                         ret = 1;
740                                 dst_release(&rt2->dst);
741                         }
742                         dst_release(&rt1->dst);
743                 }
744                 break;
745         }
746 #if IS_ENABLED(CONFIG_NF_CONNTRACK_IPV6)
747         case AF_INET6: {
748                 struct flowi6 fl1, fl2;
749                 struct rt6_info *rt1, *rt2;
750
751                 memset(&fl1, 0, sizeof(fl1));
752                 fl1.daddr = src->in6;
753
754                 memset(&fl2, 0, sizeof(fl2));
755                 fl2.daddr = dst->in6;
756                 if (!afinfo->route(&init_net, (struct dst_entry **)&rt1,
757                                    flowi6_to_flowi(&fl1), false)) {
758                         if (!afinfo->route(&init_net, (struct dst_entry **)&rt2,
759                                            flowi6_to_flowi(&fl2), false)) {
760                                 if (!memcmp(&rt1->rt6i_gateway, &rt2->rt6i_gateway,
761                                             sizeof(rt1->rt6i_gateway)) &&
762                                     rt1->dst.dev == rt2->dst.dev)
763                                         ret = 1;
764                                 dst_release(&rt2->dst);
765                         }
766                         dst_release(&rt1->dst);
767                 }
768                 break;
769         }
770 #endif
771         }
772         return ret;
773
774 }
775
776 /****************************************************************************/
777 static int expect_callforwarding(struct sk_buff *skb,
778                                  struct nf_conn *ct,
779                                  enum ip_conntrack_info ctinfo,
780                                  unsigned char **data, int dataoff,
781                                  TransportAddress *taddr)
782 {
783         int dir = CTINFO2DIR(ctinfo);
784         int ret = 0;
785         __be16 port;
786         union nf_inet_addr addr;
787         struct nf_conntrack_expect *exp;
788         typeof(nat_callforwarding_hook) nat_callforwarding;
789
790         /* Read alternativeAddress */
791         if (!get_h225_addr(ct, *data, taddr, &addr, &port) || port == 0)
792                 return 0;
793
794         /* If the calling party is on the same side of the forward-to party,
795          * we don't need to track the second call */
796         if (callforward_filter &&
797             callforward_do_filter(&addr, &ct->tuplehash[!dir].tuple.src.u3,
798                                   nf_ct_l3num(ct))) {
799                 pr_debug("nf_ct_q931: Call Forwarding not tracked\n");
800                 return 0;
801         }
802
803         /* Create expect for the second call leg */
804         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
805                 return -1;
806         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
807                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
808                           IPPROTO_TCP, NULL, &port);
809         exp->helper = nf_conntrack_helper_q931;
810
811         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
812                    &ct->tuplehash[!dir].tuple.dst.u3,
813                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
814             (nat_callforwarding = rcu_dereference(nat_callforwarding_hook)) &&
815             ct->status & IPS_NAT_MASK) {
816                 /* Need NAT */
817                 ret = nat_callforwarding(skb, ct, ctinfo, data, dataoff,
818                                          taddr, port, exp);
819         } else {                /* Conntrack only */
820                 if (nf_ct_expect_related(exp) == 0) {
821                         pr_debug("nf_ct_q931: expect Call Forwarding ");
822                         nf_ct_dump_tuple(&exp->tuple);
823                 } else
824                         ret = -1;
825         }
826
827         nf_ct_expect_put(exp);
828
829         return ret;
830 }
831
832 /****************************************************************************/
833 static int process_setup(struct sk_buff *skb, struct nf_conn *ct,
834                          enum ip_conntrack_info ctinfo,
835                          unsigned char **data, int dataoff,
836                          Setup_UUIE *setup)
837 {
838         int dir = CTINFO2DIR(ctinfo);
839         int ret;
840         int i;
841         __be16 port;
842         union nf_inet_addr addr;
843         typeof(set_h225_addr_hook) set_h225_addr;
844
845         pr_debug("nf_ct_q931: Setup\n");
846
847         if (setup->options & eSetup_UUIE_h245Address) {
848                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
849                                   &setup->h245Address);
850                 if (ret < 0)
851                         return -1;
852         }
853
854         set_h225_addr = rcu_dereference(set_h225_addr_hook);
855         if ((setup->options & eSetup_UUIE_destCallSignalAddress) &&
856             (set_h225_addr) && ct->status & IPS_NAT_MASK &&
857             get_h225_addr(ct, *data, &setup->destCallSignalAddress,
858                           &addr, &port) &&
859             memcmp(&addr, &ct->tuplehash[!dir].tuple.src.u3, sizeof(addr))) {
860                 pr_debug("nf_ct_q931: set destCallSignalAddress %pI6:%hu->%pI6:%hu\n",
861                          &addr, ntohs(port), &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 %pI6:%hu->%pI6:%hu\n",
877                          &addr, ntohs(port), &ct->tuplehash[!dir].tuple.dst.u3,
878                          ntohs(ct->tuplehash[!dir].tuple.dst.u.tcp.port));
879                 ret = set_h225_addr(skb, data, dataoff,
880                                     &setup->sourceCallSignalAddress,
881                                     &ct->tuplehash[!dir].tuple.dst.u3,
882                                     ct->tuplehash[!dir].tuple.dst.u.tcp.port);
883                 if (ret < 0)
884                         return -1;
885         }
886
887         if (setup->options & eSetup_UUIE_fastStart) {
888                 for (i = 0; i < setup->fastStart.count; i++) {
889                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
890                                           &setup->fastStart.item[i]);
891                         if (ret < 0)
892                                 return -1;
893                 }
894         }
895
896         return 0;
897 }
898
899 /****************************************************************************/
900 static int process_callproceeding(struct sk_buff *skb,
901                                   struct nf_conn *ct,
902                                   enum ip_conntrack_info ctinfo,
903                                   unsigned char **data, int dataoff,
904                                   CallProceeding_UUIE *callproc)
905 {
906         int ret;
907         int i;
908
909         pr_debug("nf_ct_q931: CallProceeding\n");
910
911         if (callproc->options & eCallProceeding_UUIE_h245Address) {
912                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
913                                   &callproc->h245Address);
914                 if (ret < 0)
915                         return -1;
916         }
917
918         if (callproc->options & eCallProceeding_UUIE_fastStart) {
919                 for (i = 0; i < callproc->fastStart.count; i++) {
920                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
921                                           &callproc->fastStart.item[i]);
922                         if (ret < 0)
923                                 return -1;
924                 }
925         }
926
927         return 0;
928 }
929
930 /****************************************************************************/
931 static int process_connect(struct sk_buff *skb, struct nf_conn *ct,
932                            enum ip_conntrack_info ctinfo,
933                            unsigned char **data, int dataoff,
934                            Connect_UUIE *connect)
935 {
936         int ret;
937         int i;
938
939         pr_debug("nf_ct_q931: Connect\n");
940
941         if (connect->options & eConnect_UUIE_h245Address) {
942                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
943                                   &connect->h245Address);
944                 if (ret < 0)
945                         return -1;
946         }
947
948         if (connect->options & eConnect_UUIE_fastStart) {
949                 for (i = 0; i < connect->fastStart.count; i++) {
950                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
951                                           &connect->fastStart.item[i]);
952                         if (ret < 0)
953                                 return -1;
954                 }
955         }
956
957         return 0;
958 }
959
960 /****************************************************************************/
961 static int process_alerting(struct sk_buff *skb, struct nf_conn *ct,
962                             enum ip_conntrack_info ctinfo,
963                             unsigned char **data, int dataoff,
964                             Alerting_UUIE *alert)
965 {
966         int ret;
967         int i;
968
969         pr_debug("nf_ct_q931: Alerting\n");
970
971         if (alert->options & eAlerting_UUIE_h245Address) {
972                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
973                                   &alert->h245Address);
974                 if (ret < 0)
975                         return -1;
976         }
977
978         if (alert->options & eAlerting_UUIE_fastStart) {
979                 for (i = 0; i < alert->fastStart.count; i++) {
980                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
981                                           &alert->fastStart.item[i]);
982                         if (ret < 0)
983                                 return -1;
984                 }
985         }
986
987         return 0;
988 }
989
990 /****************************************************************************/
991 static int process_facility(struct sk_buff *skb, struct nf_conn *ct,
992                             enum ip_conntrack_info ctinfo,
993                             unsigned char **data, int dataoff,
994                             Facility_UUIE *facility)
995 {
996         int ret;
997         int i;
998
999         pr_debug("nf_ct_q931: Facility\n");
1000
1001         if (facility->reason.choice == eFacilityReason_callForwarded) {
1002                 if (facility->options & eFacility_UUIE_alternativeAddress)
1003                         return expect_callforwarding(skb, ct, ctinfo, data,
1004                                                      dataoff,
1005                                                      &facility->
1006                                                      alternativeAddress);
1007                 return 0;
1008         }
1009
1010         if (facility->options & eFacility_UUIE_h245Address) {
1011                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
1012                                   &facility->h245Address);
1013                 if (ret < 0)
1014                         return -1;
1015         }
1016
1017         if (facility->options & eFacility_UUIE_fastStart) {
1018                 for (i = 0; i < facility->fastStart.count; i++) {
1019                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
1020                                           &facility->fastStart.item[i]);
1021                         if (ret < 0)
1022                                 return -1;
1023                 }
1024         }
1025
1026         return 0;
1027 }
1028
1029 /****************************************************************************/
1030 static int process_progress(struct sk_buff *skb, struct nf_conn *ct,
1031                             enum ip_conntrack_info ctinfo,
1032                             unsigned char **data, int dataoff,
1033                             Progress_UUIE *progress)
1034 {
1035         int ret;
1036         int i;
1037
1038         pr_debug("nf_ct_q931: Progress\n");
1039
1040         if (progress->options & eProgress_UUIE_h245Address) {
1041                 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
1042                                   &progress->h245Address);
1043                 if (ret < 0)
1044                         return -1;
1045         }
1046
1047         if (progress->options & eProgress_UUIE_fastStart) {
1048                 for (i = 0; i < progress->fastStart.count; i++) {
1049                         ret = process_olc(skb, ct, ctinfo, data, dataoff,
1050                                           &progress->fastStart.item[i]);
1051                         if (ret < 0)
1052                                 return -1;
1053                 }
1054         }
1055
1056         return 0;
1057 }
1058
1059 /****************************************************************************/
1060 static int process_q931(struct sk_buff *skb, struct nf_conn *ct,
1061                         enum ip_conntrack_info ctinfo,
1062                         unsigned char **data, int dataoff, Q931 *q931)
1063 {
1064         H323_UU_PDU *pdu = &q931->UUIE.h323_uu_pdu;
1065         int i;
1066         int ret = 0;
1067
1068         switch (pdu->h323_message_body.choice) {
1069         case eH323_UU_PDU_h323_message_body_setup:
1070                 ret = process_setup(skb, ct, ctinfo, data, dataoff,
1071                                     &pdu->h323_message_body.setup);
1072                 break;
1073         case eH323_UU_PDU_h323_message_body_callProceeding:
1074                 ret = process_callproceeding(skb, ct, ctinfo, data, dataoff,
1075                                              &pdu->h323_message_body.
1076                                              callProceeding);
1077                 break;
1078         case eH323_UU_PDU_h323_message_body_connect:
1079                 ret = process_connect(skb, ct, ctinfo, data, dataoff,
1080                                       &pdu->h323_message_body.connect);
1081                 break;
1082         case eH323_UU_PDU_h323_message_body_alerting:
1083                 ret = process_alerting(skb, ct, ctinfo, data, dataoff,
1084                                        &pdu->h323_message_body.alerting);
1085                 break;
1086         case eH323_UU_PDU_h323_message_body_facility:
1087                 ret = process_facility(skb, ct, ctinfo, data, dataoff,
1088                                        &pdu->h323_message_body.facility);
1089                 break;
1090         case eH323_UU_PDU_h323_message_body_progress:
1091                 ret = process_progress(skb, ct, ctinfo, data, dataoff,
1092                                        &pdu->h323_message_body.progress);
1093                 break;
1094         default:
1095                 pr_debug("nf_ct_q931: Q.931 signal %d\n",
1096                          pdu->h323_message_body.choice);
1097                 break;
1098         }
1099
1100         if (ret < 0)
1101                 return -1;
1102
1103         if (pdu->options & eH323_UU_PDU_h245Control) {
1104                 for (i = 0; i < pdu->h245Control.count; i++) {
1105                         ret = process_h245(skb, ct, ctinfo, data, dataoff,
1106                                            &pdu->h245Control.item[i]);
1107                         if (ret < 0)
1108                                 return -1;
1109                 }
1110         }
1111
1112         return 0;
1113 }
1114
1115 /****************************************************************************/
1116 static int q931_help(struct sk_buff *skb, unsigned int protoff,
1117                      struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1118 {
1119         static Q931 q931;
1120         unsigned char *data = NULL;
1121         int datalen;
1122         int dataoff;
1123         int ret;
1124
1125         /* Until there's been traffic both ways, don't look in packets. */
1126         if (ctinfo != IP_CT_ESTABLISHED && ctinfo != IP_CT_ESTABLISHED_REPLY)
1127                 return NF_ACCEPT;
1128
1129         pr_debug("nf_ct_q931: skblen = %u\n", skb->len);
1130
1131         spin_lock_bh(&nf_h323_lock);
1132
1133         /* Process each TPKT */
1134         while (get_tpkt_data(skb, protoff, ct, ctinfo,
1135                              &data, &datalen, &dataoff)) {
1136                 pr_debug("nf_ct_q931: TPKT len=%d ", datalen);
1137                 nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1138
1139                 /* Decode Q.931 signal */
1140                 ret = DecodeQ931(data, datalen, &q931);
1141                 if (ret < 0) {
1142                         pr_debug("nf_ct_q931: decoding error: %s\n",
1143                                  ret == H323_ERROR_BOUND ?
1144                                  "out of bound" : "out of range");
1145                         /* We don't drop when decoding error */
1146                         break;
1147                 }
1148
1149                 /* Process Q.931 signal */
1150                 if (process_q931(skb, ct, ctinfo, &data, dataoff, &q931) < 0)
1151                         goto drop;
1152         }
1153
1154         spin_unlock_bh(&nf_h323_lock);
1155         return NF_ACCEPT;
1156
1157       drop:
1158         spin_unlock_bh(&nf_h323_lock);
1159         net_info_ratelimited("nf_ct_q931: packet dropped\n");
1160         return NF_DROP;
1161 }
1162
1163 /****************************************************************************/
1164 static const struct nf_conntrack_expect_policy q931_exp_policy = {
1165         /* T.120 and H.245 */
1166         .max_expected           = H323_RTP_CHANNEL_MAX * 4 + 4,
1167         .timeout                = 240,
1168 };
1169
1170 static struct nf_conntrack_helper nf_conntrack_helper_q931[] __read_mostly = {
1171         {
1172                 .name                   = "Q.931",
1173                 .me                     = THIS_MODULE,
1174                 .data_len               = sizeof(struct nf_ct_h323_master),
1175                 .tuple.src.l3num        = AF_INET,
1176                 .tuple.src.u.tcp.port   = cpu_to_be16(Q931_PORT),
1177                 .tuple.dst.protonum     = IPPROTO_TCP,
1178                 .help                   = q931_help,
1179                 .expect_policy          = &q931_exp_policy,
1180         },
1181         {
1182                 .name                   = "Q.931",
1183                 .me                     = THIS_MODULE,
1184                 .tuple.src.l3num        = AF_INET6,
1185                 .tuple.src.u.tcp.port   = cpu_to_be16(Q931_PORT),
1186                 .tuple.dst.protonum     = IPPROTO_TCP,
1187                 .help                   = q931_help,
1188                 .expect_policy          = &q931_exp_policy,
1189         },
1190 };
1191
1192 /****************************************************************************/
1193 static unsigned char *get_udp_data(struct sk_buff *skb, unsigned int protoff,
1194                                    int *datalen)
1195 {
1196         const struct udphdr *uh;
1197         struct udphdr _uh;
1198         int dataoff;
1199
1200         uh = skb_header_pointer(skb, protoff, sizeof(_uh), &_uh);
1201         if (uh == NULL)
1202                 return NULL;
1203         dataoff = protoff + sizeof(_uh);
1204         if (dataoff >= skb->len)
1205                 return NULL;
1206         *datalen = skb->len - dataoff;
1207         return skb_header_pointer(skb, dataoff, *datalen, h323_buffer);
1208 }
1209
1210 /****************************************************************************/
1211 static struct nf_conntrack_expect *find_expect(struct nf_conn *ct,
1212                                                union nf_inet_addr *addr,
1213                                                __be16 port)
1214 {
1215         struct net *net = nf_ct_net(ct);
1216         struct nf_conntrack_expect *exp;
1217         struct nf_conntrack_tuple tuple;
1218
1219         memset(&tuple.src.u3, 0, sizeof(tuple.src.u3));
1220         tuple.src.u.tcp.port = 0;
1221         memcpy(&tuple.dst.u3, addr, sizeof(tuple.dst.u3));
1222         tuple.dst.u.tcp.port = port;
1223         tuple.dst.protonum = IPPROTO_TCP;
1224
1225         exp = __nf_ct_expect_find(net, nf_ct_zone(ct), &tuple);
1226         if (exp && exp->master == ct)
1227                 return exp;
1228         return NULL;
1229 }
1230
1231 /****************************************************************************/
1232 static int set_expect_timeout(struct nf_conntrack_expect *exp,
1233                               unsigned int timeout)
1234 {
1235         if (!exp || !del_timer(&exp->timeout))
1236                 return 0;
1237
1238         exp->timeout.expires = jiffies + timeout * HZ;
1239         add_timer(&exp->timeout);
1240
1241         return 1;
1242 }
1243
1244 /****************************************************************************/
1245 static int expect_q931(struct sk_buff *skb, struct nf_conn *ct,
1246                        enum ip_conntrack_info ctinfo,
1247                        unsigned char **data,
1248                        TransportAddress *taddr, int count)
1249 {
1250         struct nf_ct_h323_master *info = nfct_help_data(ct);
1251         int dir = CTINFO2DIR(ctinfo);
1252         int ret = 0;
1253         int i;
1254         __be16 port;
1255         union nf_inet_addr addr;
1256         struct nf_conntrack_expect *exp;
1257         typeof(nat_q931_hook) nat_q931;
1258
1259         /* Look for the first related address */
1260         for (i = 0; i < count; i++) {
1261                 if (get_h225_addr(ct, *data, &taddr[i], &addr, &port) &&
1262                     memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3,
1263                            sizeof(addr)) == 0 && port != 0)
1264                         break;
1265         }
1266
1267         if (i >= count)         /* Not found */
1268                 return 0;
1269
1270         /* Create expect for Q.931 */
1271         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1272                 return -1;
1273         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1274                           gkrouted_only ? /* only accept calls from GK? */
1275                                 &ct->tuplehash[!dir].tuple.src.u3 : NULL,
1276                           &ct->tuplehash[!dir].tuple.dst.u3,
1277                           IPPROTO_TCP, NULL, &port);
1278         exp->helper = nf_conntrack_helper_q931;
1279         exp->flags = NF_CT_EXPECT_PERMANENT;    /* Accept multiple calls */
1280
1281         nat_q931 = rcu_dereference(nat_q931_hook);
1282         if (nat_q931 && ct->status & IPS_NAT_MASK) {    /* Need NAT */
1283                 ret = nat_q931(skb, ct, ctinfo, data, taddr, i, port, exp);
1284         } else {                /* Conntrack only */
1285                 if (nf_ct_expect_related(exp) == 0) {
1286                         pr_debug("nf_ct_ras: expect Q.931 ");
1287                         nf_ct_dump_tuple(&exp->tuple);
1288
1289                         /* Save port for looking up expect in processing RCF */
1290                         info->sig_port[dir] = port;
1291                 } else
1292                         ret = -1;
1293         }
1294
1295         nf_ct_expect_put(exp);
1296
1297         return ret;
1298 }
1299
1300 /****************************************************************************/
1301 static int process_grq(struct sk_buff *skb, struct nf_conn *ct,
1302                        enum ip_conntrack_info ctinfo,
1303                        unsigned char **data, GatekeeperRequest *grq)
1304 {
1305         typeof(set_ras_addr_hook) set_ras_addr;
1306
1307         pr_debug("nf_ct_ras: GRQ\n");
1308
1309         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1310         if (set_ras_addr && ct->status & IPS_NAT_MASK)  /* NATed */
1311                 return set_ras_addr(skb, ct, ctinfo, data,
1312                                     &grq->rasAddress, 1);
1313         return 0;
1314 }
1315
1316 /****************************************************************************/
1317 static int process_gcf(struct sk_buff *skb, struct nf_conn *ct,
1318                        enum ip_conntrack_info ctinfo,
1319                        unsigned char **data, GatekeeperConfirm *gcf)
1320 {
1321         int dir = CTINFO2DIR(ctinfo);
1322         int ret = 0;
1323         __be16 port;
1324         union nf_inet_addr addr;
1325         struct nf_conntrack_expect *exp;
1326
1327         pr_debug("nf_ct_ras: GCF\n");
1328
1329         if (!get_h225_addr(ct, *data, &gcf->rasAddress, &addr, &port))
1330                 return 0;
1331
1332         /* Registration port is the same as discovery port */
1333         if (!memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1334             port == ct->tuplehash[dir].tuple.src.u.udp.port)
1335                 return 0;
1336
1337         /* Avoid RAS expectation loops. A GCF is never expected. */
1338         if (test_bit(IPS_EXPECTED_BIT, &ct->status))
1339                 return 0;
1340
1341         /* Need new expect */
1342         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1343                 return -1;
1344         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1345                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1346                           IPPROTO_UDP, NULL, &port);
1347         exp->helper = nf_conntrack_helper_ras;
1348
1349         if (nf_ct_expect_related(exp) == 0) {
1350                 pr_debug("nf_ct_ras: expect RAS ");
1351                 nf_ct_dump_tuple(&exp->tuple);
1352         } else
1353                 ret = -1;
1354
1355         nf_ct_expect_put(exp);
1356
1357         return ret;
1358 }
1359
1360 /****************************************************************************/
1361 static int process_rrq(struct sk_buff *skb, struct nf_conn *ct,
1362                        enum ip_conntrack_info ctinfo,
1363                        unsigned char **data, RegistrationRequest *rrq)
1364 {
1365         struct nf_ct_h323_master *info = nfct_help_data(ct);
1366         int ret;
1367         typeof(set_ras_addr_hook) set_ras_addr;
1368
1369         pr_debug("nf_ct_ras: RRQ\n");
1370
1371         ret = expect_q931(skb, ct, ctinfo, data,
1372                           rrq->callSignalAddress.item,
1373                           rrq->callSignalAddress.count);
1374         if (ret < 0)
1375                 return -1;
1376
1377         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1378         if (set_ras_addr && ct->status & IPS_NAT_MASK) {
1379                 ret = set_ras_addr(skb, ct, ctinfo, data,
1380                                    rrq->rasAddress.item,
1381                                    rrq->rasAddress.count);
1382                 if (ret < 0)
1383                         return -1;
1384         }
1385
1386         if (rrq->options & eRegistrationRequest_timeToLive) {
1387                 pr_debug("nf_ct_ras: RRQ TTL = %u seconds\n", rrq->timeToLive);
1388                 info->timeout = rrq->timeToLive;
1389         } else
1390                 info->timeout = default_rrq_ttl;
1391
1392         return 0;
1393 }
1394
1395 /****************************************************************************/
1396 static int process_rcf(struct sk_buff *skb, struct nf_conn *ct,
1397                        enum ip_conntrack_info ctinfo,
1398                        unsigned char **data, RegistrationConfirm *rcf)
1399 {
1400         struct nf_ct_h323_master *info = nfct_help_data(ct);
1401         int dir = CTINFO2DIR(ctinfo);
1402         int ret;
1403         struct nf_conntrack_expect *exp;
1404         typeof(set_sig_addr_hook) set_sig_addr;
1405
1406         pr_debug("nf_ct_ras: RCF\n");
1407
1408         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1409         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1410                 ret = set_sig_addr(skb, ct, ctinfo, data,
1411                                         rcf->callSignalAddress.item,
1412                                         rcf->callSignalAddress.count);
1413                 if (ret < 0)
1414                         return -1;
1415         }
1416
1417         if (rcf->options & eRegistrationConfirm_timeToLive) {
1418                 pr_debug("nf_ct_ras: RCF TTL = %u seconds\n", rcf->timeToLive);
1419                 info->timeout = rcf->timeToLive;
1420         }
1421
1422         if (info->timeout > 0) {
1423                 pr_debug("nf_ct_ras: set RAS connection timeout to "
1424                          "%u seconds\n", info->timeout);
1425                 nf_ct_refresh(ct, skb, info->timeout * HZ);
1426
1427                 /* Set expect timeout */
1428                 spin_lock_bh(&nf_conntrack_lock);
1429                 exp = find_expect(ct, &ct->tuplehash[dir].tuple.dst.u3,
1430                                   info->sig_port[!dir]);
1431                 if (exp) {
1432                         pr_debug("nf_ct_ras: set Q.931 expect "
1433                                  "timeout to %u seconds for",
1434                                  info->timeout);
1435                         nf_ct_dump_tuple(&exp->tuple);
1436                         set_expect_timeout(exp, info->timeout);
1437                 }
1438                 spin_unlock_bh(&nf_conntrack_lock);
1439         }
1440
1441         return 0;
1442 }
1443
1444 /****************************************************************************/
1445 static int process_urq(struct sk_buff *skb, struct nf_conn *ct,
1446                        enum ip_conntrack_info ctinfo,
1447                        unsigned char **data, UnregistrationRequest *urq)
1448 {
1449         struct nf_ct_h323_master *info = nfct_help_data(ct);
1450         int dir = CTINFO2DIR(ctinfo);
1451         int ret;
1452         typeof(set_sig_addr_hook) set_sig_addr;
1453
1454         pr_debug("nf_ct_ras: URQ\n");
1455
1456         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1457         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1458                 ret = set_sig_addr(skb, ct, ctinfo, data,
1459                                    urq->callSignalAddress.item,
1460                                    urq->callSignalAddress.count);
1461                 if (ret < 0)
1462                         return -1;
1463         }
1464
1465         /* Clear old expect */
1466         nf_ct_remove_expectations(ct);
1467         info->sig_port[dir] = 0;
1468         info->sig_port[!dir] = 0;
1469
1470         /* Give it 30 seconds for UCF or URJ */
1471         nf_ct_refresh(ct, skb, 30 * HZ);
1472
1473         return 0;
1474 }
1475
1476 /****************************************************************************/
1477 static int process_arq(struct sk_buff *skb, struct nf_conn *ct,
1478                        enum ip_conntrack_info ctinfo,
1479                        unsigned char **data, AdmissionRequest *arq)
1480 {
1481         const struct nf_ct_h323_master *info = nfct_help_data(ct);
1482         int dir = CTINFO2DIR(ctinfo);
1483         __be16 port;
1484         union nf_inet_addr addr;
1485         typeof(set_h225_addr_hook) set_h225_addr;
1486
1487         pr_debug("nf_ct_ras: ARQ\n");
1488
1489         set_h225_addr = rcu_dereference(set_h225_addr_hook);
1490         if ((arq->options & eAdmissionRequest_destCallSignalAddress) &&
1491             get_h225_addr(ct, *data, &arq->destCallSignalAddress,
1492                           &addr, &port) &&
1493             !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1494             port == info->sig_port[dir] &&
1495             set_h225_addr && ct->status & IPS_NAT_MASK) {
1496                 /* Answering ARQ */
1497                 return set_h225_addr(skb, data, 0,
1498                                      &arq->destCallSignalAddress,
1499                                      &ct->tuplehash[!dir].tuple.dst.u3,
1500                                      info->sig_port[!dir]);
1501         }
1502
1503         if ((arq->options & eAdmissionRequest_srcCallSignalAddress) &&
1504             get_h225_addr(ct, *data, &arq->srcCallSignalAddress,
1505                           &addr, &port) &&
1506             !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1507             set_h225_addr && ct->status & IPS_NAT_MASK) {
1508                 /* Calling ARQ */
1509                 return set_h225_addr(skb, data, 0,
1510                                      &arq->srcCallSignalAddress,
1511                                      &ct->tuplehash[!dir].tuple.dst.u3,
1512                                      port);
1513         }
1514
1515         return 0;
1516 }
1517
1518 /****************************************************************************/
1519 static int process_acf(struct sk_buff *skb, struct nf_conn *ct,
1520                        enum ip_conntrack_info ctinfo,
1521                        unsigned char **data, AdmissionConfirm *acf)
1522 {
1523         int dir = CTINFO2DIR(ctinfo);
1524         int ret = 0;
1525         __be16 port;
1526         union nf_inet_addr addr;
1527         struct nf_conntrack_expect *exp;
1528         typeof(set_sig_addr_hook) set_sig_addr;
1529
1530         pr_debug("nf_ct_ras: ACF\n");
1531
1532         if (!get_h225_addr(ct, *data, &acf->destCallSignalAddress,
1533                            &addr, &port))
1534                 return 0;
1535
1536         if (!memcmp(&addr, &ct->tuplehash[dir].tuple.dst.u3, sizeof(addr))) {
1537                 /* Answering ACF */
1538                 set_sig_addr = rcu_dereference(set_sig_addr_hook);
1539                 if (set_sig_addr && ct->status & IPS_NAT_MASK)
1540                         return set_sig_addr(skb, ct, ctinfo, data,
1541                                             &acf->destCallSignalAddress, 1);
1542                 return 0;
1543         }
1544
1545         /* Need new expect */
1546         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1547                 return -1;
1548         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1549                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1550                           IPPROTO_TCP, NULL, &port);
1551         exp->flags = NF_CT_EXPECT_PERMANENT;
1552         exp->helper = nf_conntrack_helper_q931;
1553
1554         if (nf_ct_expect_related(exp) == 0) {
1555                 pr_debug("nf_ct_ras: expect Q.931 ");
1556                 nf_ct_dump_tuple(&exp->tuple);
1557         } else
1558                 ret = -1;
1559
1560         nf_ct_expect_put(exp);
1561
1562         return ret;
1563 }
1564
1565 /****************************************************************************/
1566 static int process_lrq(struct sk_buff *skb, struct nf_conn *ct,
1567                        enum ip_conntrack_info ctinfo,
1568                        unsigned char **data, LocationRequest *lrq)
1569 {
1570         typeof(set_ras_addr_hook) set_ras_addr;
1571
1572         pr_debug("nf_ct_ras: LRQ\n");
1573
1574         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1575         if (set_ras_addr && ct->status & IPS_NAT_MASK)
1576                 return set_ras_addr(skb, ct, ctinfo, data,
1577                                     &lrq->replyAddress, 1);
1578         return 0;
1579 }
1580
1581 /****************************************************************************/
1582 static int process_lcf(struct sk_buff *skb, struct nf_conn *ct,
1583                        enum ip_conntrack_info ctinfo,
1584                        unsigned char **data, LocationConfirm *lcf)
1585 {
1586         int dir = CTINFO2DIR(ctinfo);
1587         int ret = 0;
1588         __be16 port;
1589         union nf_inet_addr addr;
1590         struct nf_conntrack_expect *exp;
1591
1592         pr_debug("nf_ct_ras: LCF\n");
1593
1594         if (!get_h225_addr(ct, *data, &lcf->callSignalAddress,
1595                            &addr, &port))
1596                 return 0;
1597
1598         /* Need new expect for call signal */
1599         if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1600                 return -1;
1601         nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1602                           &ct->tuplehash[!dir].tuple.src.u3, &addr,
1603                           IPPROTO_TCP, NULL, &port);
1604         exp->flags = NF_CT_EXPECT_PERMANENT;
1605         exp->helper = nf_conntrack_helper_q931;
1606
1607         if (nf_ct_expect_related(exp) == 0) {
1608                 pr_debug("nf_ct_ras: expect Q.931 ");
1609                 nf_ct_dump_tuple(&exp->tuple);
1610         } else
1611                 ret = -1;
1612
1613         nf_ct_expect_put(exp);
1614
1615         /* Ignore rasAddress */
1616
1617         return ret;
1618 }
1619
1620 /****************************************************************************/
1621 static int process_irr(struct sk_buff *skb, struct nf_conn *ct,
1622                        enum ip_conntrack_info ctinfo,
1623                        unsigned char **data, InfoRequestResponse *irr)
1624 {
1625         int ret;
1626         typeof(set_ras_addr_hook) set_ras_addr;
1627         typeof(set_sig_addr_hook) set_sig_addr;
1628
1629         pr_debug("nf_ct_ras: IRR\n");
1630
1631         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1632         if (set_ras_addr && ct->status & IPS_NAT_MASK) {
1633                 ret = set_ras_addr(skb, ct, ctinfo, data,
1634                                    &irr->rasAddress, 1);
1635                 if (ret < 0)
1636                         return -1;
1637         }
1638
1639         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1640         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1641                 ret = set_sig_addr(skb, ct, ctinfo, data,
1642                                         irr->callSignalAddress.item,
1643                                         irr->callSignalAddress.count);
1644                 if (ret < 0)
1645                         return -1;
1646         }
1647
1648         return 0;
1649 }
1650
1651 /****************************************************************************/
1652 static int process_ras(struct sk_buff *skb, struct nf_conn *ct,
1653                        enum ip_conntrack_info ctinfo,
1654                        unsigned char **data, RasMessage *ras)
1655 {
1656         switch (ras->choice) {
1657         case eRasMessage_gatekeeperRequest:
1658                 return process_grq(skb, ct, ctinfo, data,
1659                                    &ras->gatekeeperRequest);
1660         case eRasMessage_gatekeeperConfirm:
1661                 return process_gcf(skb, ct, ctinfo, data,
1662                                    &ras->gatekeeperConfirm);
1663         case eRasMessage_registrationRequest:
1664                 return process_rrq(skb, ct, ctinfo, data,
1665                                    &ras->registrationRequest);
1666         case eRasMessage_registrationConfirm:
1667                 return process_rcf(skb, ct, ctinfo, data,
1668                                    &ras->registrationConfirm);
1669         case eRasMessage_unregistrationRequest:
1670                 return process_urq(skb, ct, ctinfo, data,
1671                                    &ras->unregistrationRequest);
1672         case eRasMessage_admissionRequest:
1673                 return process_arq(skb, ct, ctinfo, data,
1674                                    &ras->admissionRequest);
1675         case eRasMessage_admissionConfirm:
1676                 return process_acf(skb, ct, ctinfo, data,
1677                                    &ras->admissionConfirm);
1678         case eRasMessage_locationRequest:
1679                 return process_lrq(skb, ct, ctinfo, data,
1680                                    &ras->locationRequest);
1681         case eRasMessage_locationConfirm:
1682                 return process_lcf(skb, ct, ctinfo, data,
1683                                    &ras->locationConfirm);
1684         case eRasMessage_infoRequestResponse:
1685                 return process_irr(skb, ct, ctinfo, data,
1686                                    &ras->infoRequestResponse);
1687         default:
1688                 pr_debug("nf_ct_ras: RAS message %d\n", ras->choice);
1689                 break;
1690         }
1691
1692         return 0;
1693 }
1694
1695 /****************************************************************************/
1696 static int ras_help(struct sk_buff *skb, unsigned int protoff,
1697                     struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1698 {
1699         static RasMessage ras;
1700         unsigned char *data;
1701         int datalen = 0;
1702         int ret;
1703
1704         pr_debug("nf_ct_ras: skblen = %u\n", skb->len);
1705
1706         spin_lock_bh(&nf_h323_lock);
1707
1708         /* Get UDP data */
1709         data = get_udp_data(skb, protoff, &datalen);
1710         if (data == NULL)
1711                 goto accept;
1712         pr_debug("nf_ct_ras: RAS message len=%d ", datalen);
1713         nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1714
1715         /* Decode RAS message */
1716         ret = DecodeRasMessage(data, datalen, &ras);
1717         if (ret < 0) {
1718                 pr_debug("nf_ct_ras: decoding error: %s\n",
1719                          ret == H323_ERROR_BOUND ?
1720                          "out of bound" : "out of range");
1721                 goto accept;
1722         }
1723
1724         /* Process RAS message */
1725         if (process_ras(skb, ct, ctinfo, &data, &ras) < 0)
1726                 goto drop;
1727
1728       accept:
1729         spin_unlock_bh(&nf_h323_lock);
1730         return NF_ACCEPT;
1731
1732       drop:
1733         spin_unlock_bh(&nf_h323_lock);
1734         net_info_ratelimited("nf_ct_ras: packet dropped\n");
1735         return NF_DROP;
1736 }
1737
1738 /****************************************************************************/
1739 static const struct nf_conntrack_expect_policy ras_exp_policy = {
1740         .max_expected           = 32,
1741         .timeout                = 240,
1742 };
1743
1744 static struct nf_conntrack_helper nf_conntrack_helper_ras[] __read_mostly = {
1745         {
1746                 .name                   = "RAS",
1747                 .me                     = THIS_MODULE,
1748                 .data_len               = sizeof(struct nf_ct_h323_master),
1749                 .tuple.src.l3num        = AF_INET,
1750                 .tuple.src.u.udp.port   = cpu_to_be16(RAS_PORT),
1751                 .tuple.dst.protonum     = IPPROTO_UDP,
1752                 .help                   = ras_help,
1753                 .expect_policy          = &ras_exp_policy,
1754         },
1755         {
1756                 .name                   = "RAS",
1757                 .me                     = THIS_MODULE,
1758                 .data_len               = sizeof(struct nf_ct_h323_master),
1759                 .tuple.src.l3num        = AF_INET6,
1760                 .tuple.src.u.udp.port   = cpu_to_be16(RAS_PORT),
1761                 .tuple.dst.protonum     = IPPROTO_UDP,
1762                 .help                   = ras_help,
1763                 .expect_policy          = &ras_exp_policy,
1764         },
1765 };
1766
1767 /****************************************************************************/
1768 static void __exit nf_conntrack_h323_fini(void)
1769 {
1770         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[1]);
1771         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1772         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1773         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1774         nf_conntrack_helper_unregister(&nf_conntrack_helper_h245);
1775         kfree(h323_buffer);
1776         pr_debug("nf_ct_h323: fini\n");
1777 }
1778
1779 /****************************************************************************/
1780 static int __init nf_conntrack_h323_init(void)
1781 {
1782         int ret;
1783
1784         h323_buffer = kmalloc(65536, GFP_KERNEL);
1785         if (!h323_buffer)
1786                 return -ENOMEM;
1787         ret = nf_conntrack_helper_register(&nf_conntrack_helper_h245);
1788         if (ret < 0)
1789                 goto err1;
1790         ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[0]);
1791         if (ret < 0)
1792                 goto err2;
1793         ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[1]);
1794         if (ret < 0)
1795                 goto err3;
1796         ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[0]);
1797         if (ret < 0)
1798                 goto err4;
1799         ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[1]);
1800         if (ret < 0)
1801                 goto err5;
1802         pr_debug("nf_ct_h323: init success\n");
1803         return 0;
1804
1805 err5:
1806         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1807 err4:
1808         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1809 err3:
1810         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1811 err2:
1812         nf_conntrack_helper_unregister(&nf_conntrack_helper_h245);
1813 err1:
1814         kfree(h323_buffer);
1815         return ret;
1816 }
1817
1818 /****************************************************************************/
1819 module_init(nf_conntrack_h323_init);
1820 module_exit(nf_conntrack_h323_fini);
1821
1822 EXPORT_SYMBOL_GPL(get_h225_addr);
1823 EXPORT_SYMBOL_GPL(set_h245_addr_hook);
1824 EXPORT_SYMBOL_GPL(set_h225_addr_hook);
1825 EXPORT_SYMBOL_GPL(set_sig_addr_hook);
1826 EXPORT_SYMBOL_GPL(set_ras_addr_hook);
1827 EXPORT_SYMBOL_GPL(nat_rtp_rtcp_hook);
1828 EXPORT_SYMBOL_GPL(nat_t120_hook);
1829 EXPORT_SYMBOL_GPL(nat_h245_hook);
1830 EXPORT_SYMBOL_GPL(nat_callforwarding_hook);
1831 EXPORT_SYMBOL_GPL(nat_q931_hook);
1832
1833 MODULE_AUTHOR("Jing Min Zhao <zhaojingmin@users.sourceforge.net>");
1834 MODULE_DESCRIPTION("H.323 connection tracking helper");
1835 MODULE_LICENSE("GPL");
1836 MODULE_ALIAS("ip_conntrack_h323");
1837 MODULE_ALIAS_NFCT_HELPER("RAS");
1838 MODULE_ALIAS_NFCT_HELPER("Q.931");
1839 MODULE_ALIAS_NFCT_HELPER("H.245");