8bb99b3675b7e12df2d5ad396d252759c2ecfaf3
[sfrench/cifs-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 #if 0
35 #define DEBUGP printk
36 #else
37 #define DEBUGP(format, args...)
38 #endif
39
40 /* Parameters */
41 static unsigned int default_rrq_ttl __read_mostly = 300;
42 module_param(default_rrq_ttl, uint, 0600);
43 MODULE_PARM_DESC(default_rrq_ttl, "use this TTL if it's missing in RRQ");
44
45 static int gkrouted_only __read_mostly = 1;
46 module_param(gkrouted_only, int, 0600);
47 MODULE_PARM_DESC(gkrouted_only, "only accept calls from gatekeeper");
48
49 static int callforward_filter __read_mostly = 1;
50 module_param(callforward_filter, bool, 0600);
51 MODULE_PARM_DESC(callforward_filter, "only create call forwarding expectations "
52                                      "if both endpoints are on different sides "
53                                      "(determined by routing information)");
54
55 /* Hooks for NAT */
56 int (*set_h245_addr_hook) (struct sk_buff **pskb,
57                            unsigned char **data, int dataoff,
58                            H245_TransportAddress *taddr,
59                            union nf_conntrack_address *addr, __be16 port)
60                            __read_mostly;
61 int (*set_h225_addr_hook) (struct sk_buff **pskb,
62                            unsigned char **data, int dataoff,
63                            TransportAddress *taddr,
64                            union nf_conntrack_address *addr, __be16 port)
65                            __read_mostly;
66 int (*set_sig_addr_hook) (struct sk_buff **pskb,
67                           struct nf_conn *ct,
68                           enum ip_conntrack_info ctinfo,
69                           unsigned char **data,
70                           TransportAddress *taddr, int count) __read_mostly;
71 int (*set_ras_addr_hook) (struct sk_buff **pskb,
72                           struct nf_conn *ct,
73                           enum ip_conntrack_info ctinfo,
74                           unsigned char **data,
75                           TransportAddress *taddr, int count) __read_mostly;
76 int (*nat_rtp_rtcp_hook) (struct sk_buff **pskb,
77                           struct nf_conn *ct,
78                           enum ip_conntrack_info ctinfo,
79                           unsigned char **data, int dataoff,
80                           H245_TransportAddress *taddr,
81                           __be16 port, __be16 rtp_port,
82                           struct nf_conntrack_expect *rtp_exp,
83                           struct nf_conntrack_expect *rtcp_exp) __read_mostly;
84 int (*nat_t120_hook) (struct sk_buff **pskb,
85                       struct nf_conn *ct,
86                       enum ip_conntrack_info ctinfo,
87                       unsigned char **data, int dataoff,
88                       H245_TransportAddress *taddr, __be16 port,
89                       struct nf_conntrack_expect *exp) __read_mostly;
90 int (*nat_h245_hook) (struct sk_buff **pskb,
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_callforwarding_hook) (struct sk_buff **pskb,
97                                 struct nf_conn *ct,
98                                 enum ip_conntrack_info ctinfo,
99                                 unsigned char **data, int dataoff,
100                                 TransportAddress *taddr, __be16 port,
101                                 struct nf_conntrack_expect *exp) __read_mostly;
102 int (*nat_q931_hook) (struct sk_buff **pskb,
103                       struct nf_conn *ct,
104                       enum ip_conntrack_info ctinfo,
105                       unsigned char **data, TransportAddress *taddr, int idx,
106                       __be16 port, struct nf_conntrack_expect *exp)
107                       __read_mostly;
108
109 static DEFINE_SPINLOCK(nf_h323_lock);
110 static char *h323_buffer;
111
112 static struct nf_conntrack_helper nf_conntrack_helper_h245;
113 static struct nf_conntrack_helper nf_conntrack_helper_q931[];
114 static struct nf_conntrack_helper nf_conntrack_helper_ras[];
115
116 /****************************************************************************/
117 static int get_tpkt_data(struct sk_buff **pskb, unsigned int protoff,
118                          struct nf_conn *ct, enum ip_conntrack_info ctinfo,
119                          unsigned char **data, int *datalen, int *dataoff)
120 {
121         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
122         int dir = CTINFO2DIR(ctinfo);
123         struct tcphdr _tcph, *th;
124         int tcpdatalen;
125         int tcpdataoff;
126         unsigned char *tpkt;
127         int tpktlen;
128         int tpktoff;
129
130         /* Get TCP header */
131         th = skb_header_pointer(*pskb, protoff, sizeof(_tcph), &_tcph);
132         if (th == NULL)
133                 return 0;
134
135         /* Get TCP data offset */
136         tcpdataoff = protoff + th->doff * 4;
137
138         /* Get TCP data length */
139         tcpdatalen = (*pskb)->len - tcpdataoff;
140         if (tcpdatalen <= 0)    /* No TCP data */
141                 goto clear_out;
142
143         if (*data == NULL) {    /* first TPKT */
144                 /* Get first TPKT pointer */
145                 tpkt = skb_header_pointer(*pskb, tcpdataoff, tcpdatalen,
146                                           h323_buffer);
147                 BUG_ON(tpkt == NULL);
148
149                 /* Validate TPKT identifier */
150                 if (tcpdatalen < 4 || tpkt[0] != 0x03 || tpkt[1] != 0) {
151                         /* Netmeeting sends TPKT header and data separately */
152                         if (info->tpkt_len[dir] > 0) {
153                                 DEBUGP("nf_ct_h323: previous packet "
154                                        "indicated separate TPKT data of %hu "
155                                        "bytes\n", info->tpkt_len[dir]);
156                                 if (info->tpkt_len[dir] <= tcpdatalen) {
157                                         /* Yes, there was a TPKT header
158                                          * received */
159                                         *data = tpkt;
160                                         *datalen = info->tpkt_len[dir];
161                                         *dataoff = 0;
162                                         goto out;
163                                 }
164
165                                 /* Fragmented TPKT */
166                                 if (net_ratelimit())
167                                         printk("nf_ct_h323: "
168                                                "fragmented TPKT\n");
169                                 goto clear_out;
170                         }
171
172                         /* It is not even a TPKT */
173                         return 0;
174                 }
175                 tpktoff = 0;
176         } else {                /* Next TPKT */
177                 tpktoff = *dataoff + *datalen;
178                 tcpdatalen -= tpktoff;
179                 if (tcpdatalen <= 4)    /* No more TPKT */
180                         goto clear_out;
181                 tpkt = *data + *datalen;
182
183                 /* Validate TPKT identifier */
184                 if (tpkt[0] != 0x03 || tpkt[1] != 0)
185                         goto clear_out;
186         }
187
188         /* Validate TPKT length */
189         tpktlen = tpkt[2] * 256 + tpkt[3];
190         if (tpktlen < 4)
191                 goto clear_out;
192         if (tpktlen > tcpdatalen) {
193                 if (tcpdatalen == 4) {  /* Separate TPKT header */
194                         /* Netmeeting sends TPKT header and data separately */
195                         DEBUGP("nf_ct_h323: separate TPKT header indicates "
196                                "there will be TPKT data of %hu bytes\n",
197                                tpktlen - 4);
198                         info->tpkt_len[dir] = tpktlen - 4;
199                         return 0;
200                 }
201
202                 if (net_ratelimit())
203                         printk("nf_ct_h323: incomplete TPKT (fragmented?)\n");
204                 goto clear_out;
205         }
206
207         /* This is the encapsulated data */
208         *data = tpkt + 4;
209         *datalen = tpktlen - 4;
210         *dataoff = tpktoff + 4;
211
212       out:
213         /* Clear TPKT length */
214         info->tpkt_len[dir] = 0;
215         return 1;
216
217       clear_out:
218         info->tpkt_len[dir] = 0;
219         return 0;
220 }
221
222 /****************************************************************************/
223 static int get_h245_addr(struct nf_conn *ct, unsigned char *data,
224                          H245_TransportAddress *taddr,
225                          union nf_conntrack_address *addr, __be16 *port)
226 {
227         unsigned char *p;
228         int family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
229         int len;
230
231         if (taddr->choice != eH245_TransportAddress_unicastAddress)
232                 return 0;
233
234         switch (taddr->unicastAddress.choice) {
235         case eUnicastAddress_iPAddress:
236                 if (family != AF_INET)
237                         return 0;
238                 p = data + taddr->unicastAddress.iPAddress.network;
239                 len = 4;
240                 break;
241         case eUnicastAddress_iP6Address:
242                 if (family != AF_INET6)
243                         return 0;
244                 p = data + taddr->unicastAddress.iP6Address.network;
245                 len = 16;
246                 break;
247         default:
248                 return 0;
249         }
250
251         memcpy(addr, p, len);
252         memset((void *)addr + len, 0, sizeof(*addr) - len);
253         memcpy(port, p + len, sizeof(__be16));
254
255         return 1;
256 }
257
258 /****************************************************************************/
259 static int expect_rtp_rtcp(struct sk_buff **pskb, struct nf_conn *ct,
260                            enum ip_conntrack_info ctinfo,
261                            unsigned char **data, int dataoff,
262                            H245_TransportAddress *taddr)
263 {
264         int dir = CTINFO2DIR(ctinfo);
265         int ret = 0;
266         __be16 port;
267         __be16 rtp_port, rtcp_port;
268         union nf_conntrack_address addr;
269         struct nf_conntrack_expect *rtp_exp;
270         struct nf_conntrack_expect *rtcp_exp;
271         typeof(nat_rtp_rtcp_hook) nat_rtp_rtcp;
272
273         /* Read RTP or RTCP address */
274         if (!get_h245_addr(ct, *data, taddr, &addr, &port) ||
275             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
276             port == 0)
277                 return 0;
278
279         /* RTP port is even */
280         port &= htons(~1);
281         rtp_port = port;
282         rtcp_port = htons(ntohs(port) + 1);
283
284         /* Create expect for RTP */
285         if ((rtp_exp = nf_conntrack_expect_alloc(ct)) == NULL)
286                 return -1;
287         nf_conntrack_expect_init(rtp_exp, ct->tuplehash[!dir].tuple.src.l3num,
288                                  &ct->tuplehash[!dir].tuple.src.u3,
289                                  &ct->tuplehash[!dir].tuple.dst.u3,
290                                  IPPROTO_UDP, NULL, &rtp_port);
291
292         /* Create expect for RTCP */
293         if ((rtcp_exp = nf_conntrack_expect_alloc(ct)) == NULL) {
294                 nf_conntrack_expect_put(rtp_exp);
295                 return -1;
296         }
297         nf_conntrack_expect_init(rtcp_exp, ct->tuplehash[!dir].tuple.src.l3num,
298                                  &ct->tuplehash[!dir].tuple.src.u3,
299                                  &ct->tuplehash[!dir].tuple.dst.u3,
300                                  IPPROTO_UDP, NULL, &rtcp_port);
301
302         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
303                    &ct->tuplehash[!dir].tuple.dst.u3,
304                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
305                    (nat_rtp_rtcp = rcu_dereference(nat_rtp_rtcp_hook)) &&
306                    ct->status & IPS_NAT_MASK) {
307                 /* NAT needed */
308                 ret = nat_rtp_rtcp(pskb, ct, ctinfo, data, dataoff,
309                                    taddr, port, rtp_port, rtp_exp, rtcp_exp);
310         } else {                /* Conntrack only */
311                 if (nf_conntrack_expect_related(rtp_exp) == 0) {
312                         if (nf_conntrack_expect_related(rtcp_exp) == 0) {
313                                 DEBUGP("nf_ct_h323: expect RTP ");
314                                 NF_CT_DUMP_TUPLE(&rtp_exp->tuple);
315                                 DEBUGP("nf_ct_h323: expect RTCP ");
316                                 NF_CT_DUMP_TUPLE(&rtcp_exp->tuple);
317                         } else {
318                                 nf_conntrack_unexpect_related(rtp_exp);
319                                 ret = -1;
320                         }
321                 } else
322                         ret = -1;
323         }
324
325         nf_conntrack_expect_put(rtp_exp);
326         nf_conntrack_expect_put(rtcp_exp);
327
328         return ret;
329 }
330
331 /****************************************************************************/
332 static int expect_t120(struct sk_buff **pskb,
333                        struct nf_conn *ct,
334                        enum ip_conntrack_info ctinfo,
335                        unsigned char **data, int dataoff,
336                        H245_TransportAddress *taddr)
337 {
338         int dir = CTINFO2DIR(ctinfo);
339         int ret = 0;
340         __be16 port;
341         union nf_conntrack_address addr;
342         struct nf_conntrack_expect *exp;
343         typeof(nat_t120_hook) nat_t120;
344
345         /* Read T.120 address */
346         if (!get_h245_addr(ct, *data, taddr, &addr, &port) ||
347             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
348             port == 0)
349                 return 0;
350
351         /* Create expect for T.120 connections */
352         if ((exp = nf_conntrack_expect_alloc(ct)) == NULL)
353                 return -1;
354         nf_conntrack_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num,
355                                  &ct->tuplehash[!dir].tuple.src.u3,
356                                  &ct->tuplehash[!dir].tuple.dst.u3,
357                                  IPPROTO_TCP, NULL, &port);
358         exp->flags = NF_CT_EXPECT_PERMANENT;    /* Accept multiple channels */
359
360         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
361                    &ct->tuplehash[!dir].tuple.dst.u3,
362                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
363             (nat_t120 = rcu_dereference(nat_t120_hook)) &&
364             ct->status & IPS_NAT_MASK) {
365                 /* NAT needed */
366                 ret = nat_t120(pskb, ct, ctinfo, data, dataoff, taddr,
367                                port, exp);
368         } else {                /* Conntrack only */
369                 if (nf_conntrack_expect_related(exp) == 0) {
370                         DEBUGP("nf_ct_h323: expect T.120 ");
371                         NF_CT_DUMP_TUPLE(&exp->tuple);
372                 } else
373                         ret = -1;
374         }
375
376         nf_conntrack_expect_put(exp);
377
378         return ret;
379 }
380
381 /****************************************************************************/
382 static int process_h245_channel(struct sk_buff **pskb,
383                                 struct nf_conn *ct,
384                                 enum ip_conntrack_info ctinfo,
385                                 unsigned char **data, int dataoff,
386                                 H2250LogicalChannelParameters *channel)
387 {
388         int ret;
389
390         if (channel->options & eH2250LogicalChannelParameters_mediaChannel) {
391                 /* RTP */
392                 ret = expect_rtp_rtcp(pskb, ct, ctinfo, data, dataoff,
393                                       &channel->mediaChannel);
394                 if (ret < 0)
395                         return -1;
396         }
397
398         if (channel->
399             options & eH2250LogicalChannelParameters_mediaControlChannel) {
400                 /* RTCP */
401                 ret = expect_rtp_rtcp(pskb, ct, ctinfo, data, dataoff,
402                                       &channel->mediaControlChannel);
403                 if (ret < 0)
404                         return -1;
405         }
406
407         return 0;
408 }
409
410 /****************************************************************************/
411 static int process_olc(struct sk_buff **pskb, struct nf_conn *ct,
412                        enum ip_conntrack_info ctinfo,
413                        unsigned char **data, int dataoff,
414                        OpenLogicalChannel *olc)
415 {
416         int ret;
417
418         DEBUGP("nf_ct_h323: OpenLogicalChannel\n");
419
420         if (olc->forwardLogicalChannelParameters.multiplexParameters.choice ==
421             eOpenLogicalChannel_forwardLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters)
422         {
423                 ret = process_h245_channel(pskb, ct, ctinfo, data, dataoff,
424                                            &olc->
425                                            forwardLogicalChannelParameters.
426                                            multiplexParameters.
427                                            h2250LogicalChannelParameters);
428                 if (ret < 0)
429                         return -1;
430         }
431
432         if ((olc->options &
433              eOpenLogicalChannel_reverseLogicalChannelParameters) &&
434             (olc->reverseLogicalChannelParameters.options &
435              eOpenLogicalChannel_reverseLogicalChannelParameters_multiplexParameters)
436             && (olc->reverseLogicalChannelParameters.multiplexParameters.
437                 choice ==
438                 eOpenLogicalChannel_reverseLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters))
439         {
440                 ret =
441                     process_h245_channel(pskb, ct, ctinfo, data, dataoff,
442                                          &olc->
443                                          reverseLogicalChannelParameters.
444                                          multiplexParameters.
445                                          h2250LogicalChannelParameters);
446                 if (ret < 0)
447                         return -1;
448         }
449
450         if ((olc->options & eOpenLogicalChannel_separateStack) &&
451             olc->forwardLogicalChannelParameters.dataType.choice ==
452             eDataType_data &&
453             olc->forwardLogicalChannelParameters.dataType.data.application.
454             choice == eDataApplicationCapability_application_t120 &&
455             olc->forwardLogicalChannelParameters.dataType.data.application.
456             t120.choice == eDataProtocolCapability_separateLANStack &&
457             olc->separateStack.networkAddress.choice ==
458             eNetworkAccessParameters_networkAddress_localAreaAddress) {
459                 ret = expect_t120(pskb, ct, ctinfo, data, dataoff,
460                                   &olc->separateStack.networkAddress.
461                                   localAreaAddress);
462                 if (ret < 0)
463                         return -1;
464         }
465
466         return 0;
467 }
468
469 /****************************************************************************/
470 static int process_olca(struct sk_buff **pskb, struct nf_conn *ct,
471                         enum ip_conntrack_info ctinfo,
472                         unsigned char **data, int dataoff,
473                         OpenLogicalChannelAck *olca)
474 {
475         H2250LogicalChannelAckParameters *ack;
476         int ret;
477
478         DEBUGP("nf_ct_h323: OpenLogicalChannelAck\n");
479
480         if ((olca->options &
481              eOpenLogicalChannelAck_reverseLogicalChannelParameters) &&
482             (olca->reverseLogicalChannelParameters.options &
483              eOpenLogicalChannelAck_reverseLogicalChannelParameters_multiplexParameters)
484             && (olca->reverseLogicalChannelParameters.multiplexParameters.
485                 choice ==
486                 eOpenLogicalChannelAck_reverseLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters))
487         {
488                 ret = process_h245_channel(pskb, ct, ctinfo, data, dataoff,
489                                            &olca->
490                                            reverseLogicalChannelParameters.
491                                            multiplexParameters.
492                                            h2250LogicalChannelParameters);
493                 if (ret < 0)
494                         return -1;
495         }
496
497         if ((olca->options &
498              eOpenLogicalChannelAck_forwardMultiplexAckParameters) &&
499             (olca->forwardMultiplexAckParameters.choice ==
500              eOpenLogicalChannelAck_forwardMultiplexAckParameters_h2250LogicalChannelAckParameters))
501         {
502                 ack = &olca->forwardMultiplexAckParameters.
503                     h2250LogicalChannelAckParameters;
504                 if (ack->options &
505                     eH2250LogicalChannelAckParameters_mediaChannel) {
506                         /* RTP */
507                         ret = expect_rtp_rtcp(pskb, ct, ctinfo, data, dataoff,
508                                               &ack->mediaChannel);
509                         if (ret < 0)
510                                 return -1;
511                 }
512
513                 if (ack->options &
514                     eH2250LogicalChannelAckParameters_mediaControlChannel) {
515                         /* RTCP */
516                         ret = expect_rtp_rtcp(pskb, ct, ctinfo, data, dataoff,
517                                               &ack->mediaControlChannel);
518                         if (ret < 0)
519                                 return -1;
520                 }
521         }
522
523         return 0;
524 }
525
526 /****************************************************************************/
527 static int process_h245(struct sk_buff **pskb, struct nf_conn *ct,
528                         enum ip_conntrack_info ctinfo,
529                         unsigned char **data, int dataoff,
530                         MultimediaSystemControlMessage *mscm)
531 {
532         switch (mscm->choice) {
533         case eMultimediaSystemControlMessage_request:
534                 if (mscm->request.choice ==
535                     eRequestMessage_openLogicalChannel) {
536                         return process_olc(pskb, ct, ctinfo, data, dataoff,
537                                            &mscm->request.openLogicalChannel);
538                 }
539                 DEBUGP("nf_ct_h323: H.245 Request %d\n",
540                        mscm->request.choice);
541                 break;
542         case eMultimediaSystemControlMessage_response:
543                 if (mscm->response.choice ==
544                     eResponseMessage_openLogicalChannelAck) {
545                         return process_olca(pskb, ct, ctinfo, data, dataoff,
546                                             &mscm->response.
547                                             openLogicalChannelAck);
548                 }
549                 DEBUGP("nf_ct_h323: H.245 Response %d\n",
550                        mscm->response.choice);
551                 break;
552         default:
553                 DEBUGP("nf_ct_h323: H.245 signal %d\n", mscm->choice);
554                 break;
555         }
556
557         return 0;
558 }
559
560 /****************************************************************************/
561 static int h245_help(struct sk_buff **pskb, unsigned int protoff,
562                      struct nf_conn *ct, enum ip_conntrack_info ctinfo)
563 {
564         static MultimediaSystemControlMessage mscm;
565         unsigned char *data = NULL;
566         int datalen;
567         int dataoff;
568         int ret;
569
570         /* Until there's been traffic both ways, don't look in packets. */
571         if (ctinfo != IP_CT_ESTABLISHED &&
572             ctinfo != IP_CT_ESTABLISHED + IP_CT_IS_REPLY) {
573                 return NF_ACCEPT;
574         }
575         DEBUGP("nf_ct_h245: skblen = %u\n", (*pskb)->len);
576
577         spin_lock_bh(&nf_h323_lock);
578
579         /* Process each TPKT */
580         while (get_tpkt_data(pskb, protoff, ct, ctinfo,
581                              &data, &datalen, &dataoff)) {
582                 DEBUGP("nf_ct_h245: TPKT len=%d ", datalen);
583                 NF_CT_DUMP_TUPLE(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
584
585                 /* Decode H.245 signal */
586                 ret = DecodeMultimediaSystemControlMessage(data, datalen,
587                                                            &mscm);
588                 if (ret < 0) {
589                         if (net_ratelimit())
590                                 printk("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(pskb, 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         if (net_ratelimit())
608                 printk("nf_ct_h245: packet dropped\n");
609         return NF_DROP;
610 }
611
612 /****************************************************************************/
613 static struct nf_conntrack_helper nf_conntrack_helper_h245 __read_mostly = {
614         .name                   = "H.245",
615         .me                     = THIS_MODULE,
616         .max_expected           = H323_RTP_CHANNEL_MAX * 4 + 2 /* T.120 */,
617         .timeout                = 240,
618         .tuple.dst.protonum     = IPPROTO_UDP,
619         .mask.src.u.udp.port    = __constant_htons(0xFFFF),
620         .mask.dst.protonum      = 0xFF,
621         .help                   = h245_help
622 };
623
624 /****************************************************************************/
625 int get_h225_addr(struct nf_conn *ct, unsigned char *data,
626                   TransportAddress *taddr,
627                   union nf_conntrack_address *addr, __be16 *port)
628 {
629         unsigned char *p;
630         int family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
631         int len;
632
633         switch (taddr->choice) {
634         case eTransportAddress_ipAddress:
635                 if (family != AF_INET)
636                         return 0;
637                 p = data + taddr->ipAddress.ip;
638                 len = 4;
639                 break;
640         case eTransportAddress_ip6Address:
641                 if (family != AF_INET6)
642                         return 0;
643                 p = data + taddr->ip6Address.ip;
644                 len = 16;
645                 break;
646         default:
647                 return 0;
648         }
649
650         memcpy(addr, p, len);
651         memset((void *)addr + len, 0, sizeof(*addr) - len);
652         memcpy(port, p + len, sizeof(__be16));
653
654         return 1;
655 }
656
657 /****************************************************************************/
658 static int expect_h245(struct sk_buff **pskb, struct nf_conn *ct,
659                        enum ip_conntrack_info ctinfo,
660                        unsigned char **data, int dataoff,
661                        TransportAddress *taddr)
662 {
663         int dir = CTINFO2DIR(ctinfo);
664         int ret = 0;
665         __be16 port;
666         union nf_conntrack_address addr;
667         struct nf_conntrack_expect *exp;
668         typeof(nat_h245_hook) nat_h245;
669
670         /* Read h245Address */
671         if (!get_h225_addr(ct, *data, taddr, &addr, &port) ||
672             memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
673             port == 0)
674                 return 0;
675
676         /* Create expect for h245 connection */
677         if ((exp = nf_conntrack_expect_alloc(ct)) == NULL)
678                 return -1;
679         nf_conntrack_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num,
680                                  &ct->tuplehash[!dir].tuple.src.u3,
681                                  &ct->tuplehash[!dir].tuple.dst.u3,
682                                  IPPROTO_TCP, NULL, &port);
683         exp->helper = &nf_conntrack_helper_h245;
684
685         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
686                    &ct->tuplehash[!dir].tuple.dst.u3,
687                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
688             (nat_h245 = rcu_dereference(nat_h245_hook)) &&
689             ct->status & IPS_NAT_MASK) {
690                 /* NAT needed */
691                 ret = nat_h245(pskb, ct, ctinfo, data, dataoff, taddr,
692                                port, exp);
693         } else {                /* Conntrack only */
694                 if (nf_conntrack_expect_related(exp) == 0) {
695                         DEBUGP("nf_ct_q931: expect H.245 ");
696                         NF_CT_DUMP_TUPLE(&exp->tuple);
697                 } else
698                         ret = -1;
699         }
700
701         nf_conntrack_expect_put(exp);
702
703         return ret;
704 }
705
706 /* If the calling party is on the same side of the forward-to party,
707  * we don't need to track the second call */
708 static int callforward_do_filter(union nf_conntrack_address *src,
709                                  union nf_conntrack_address *dst,
710                                  int family)
711 {
712         struct flowi fl1, fl2;
713         int ret = 0;
714
715         memset(&fl1, 0, sizeof(fl1));
716         memset(&fl2, 0, sizeof(fl2));
717
718         switch (family) {
719         case AF_INET: {
720                 struct rtable *rt1, *rt2;
721
722                 fl1.fl4_dst = src->ip;
723                 fl2.fl4_dst = dst->ip;
724                 if (ip_route_output_key(&rt1, &fl1) == 0) {
725                         if (ip_route_output_key(&rt2, &fl2) == 0) {
726                                 if (rt1->rt_gateway == rt2->rt_gateway &&
727                                     rt1->u.dst.dev  == rt2->u.dst.dev)
728                                         ret = 1;
729                                 dst_release(&rt2->u.dst);
730                         }
731                         dst_release(&rt1->u.dst);
732                 }
733                 break;
734         }
735 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
736         case AF_INET6: {
737                 struct rt6_info *rt1, *rt2;
738
739                 memcpy(&fl1.fl6_dst, src, sizeof(fl1.fl6_dst));
740                 memcpy(&fl2.fl6_dst, dst, sizeof(fl2.fl6_dst));
741                 rt1 = (struct rt6_info *)ip6_route_output(NULL, &fl1);
742                 if (rt1) {
743                         rt2 = (struct rt6_info *)ip6_route_output(NULL, &fl2);
744                         if (rt2) {
745                                 if (!memcmp(&rt1->rt6i_gateway, &rt2->rt6i_gateway,
746                                             sizeof(rt1->rt6i_gateway)) &&
747                                     rt1->u.dst.dev == rt2->u.dst.dev)
748                                         ret = 1;
749                                 dst_release(&rt2->u.dst);
750                         }
751                         dst_release(&rt1->u.dst);
752                 }
753                 break;
754         }
755 #endif
756         }
757         return ret;
758
759 }
760
761 /****************************************************************************/
762 static int expect_callforwarding(struct sk_buff **pskb,
763                                  struct nf_conn *ct,
764                                  enum ip_conntrack_info ctinfo,
765                                  unsigned char **data, int dataoff,
766                                  TransportAddress *taddr)
767 {
768         int dir = CTINFO2DIR(ctinfo);
769         int ret = 0;
770         __be16 port;
771         union nf_conntrack_address addr;
772         struct nf_conntrack_expect *exp;
773         typeof(nat_callforwarding_hook) nat_callforwarding;
774
775         /* Read alternativeAddress */
776         if (!get_h225_addr(ct, *data, taddr, &addr, &port) || port == 0)
777                 return 0;
778
779         /* If the calling party is on the same side of the forward-to party,
780          * we don't need to track the second call */
781         if (callforward_filter &&
782             callforward_do_filter(&addr, &ct->tuplehash[!dir].tuple.src.u3,
783                                   ct->tuplehash[!dir].tuple.src.l3num)) {
784                 DEBUGP("nf_ct_q931: Call Forwarding not tracked\n");
785                 return 0;
786         }
787
788         /* Create expect for the second call leg */
789         if ((exp = nf_conntrack_expect_alloc(ct)) == NULL)
790                 return -1;
791         nf_conntrack_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num,
792                                  &ct->tuplehash[!dir].tuple.src.u3, &addr,
793                                  IPPROTO_TCP, NULL, &port);
794         exp->helper = nf_conntrack_helper_q931;
795
796         if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
797                    &ct->tuplehash[!dir].tuple.dst.u3,
798                    sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
799             (nat_callforwarding = rcu_dereference(nat_callforwarding_hook)) &&
800             ct->status & IPS_NAT_MASK) {
801                 /* Need NAT */
802                 ret = nat_callforwarding(pskb, ct, ctinfo, data, dataoff,
803                                          taddr, port, exp);
804         } else {                /* Conntrack only */
805                 if (nf_conntrack_expect_related(exp) == 0) {
806                         DEBUGP("nf_ct_q931: expect Call Forwarding ");
807                         NF_CT_DUMP_TUPLE(&exp->tuple);
808                 } else
809                         ret = -1;
810         }
811
812         nf_conntrack_expect_put(exp);
813
814         return ret;
815 }
816
817 /****************************************************************************/
818 static int process_setup(struct sk_buff **pskb, struct nf_conn *ct,
819                          enum ip_conntrack_info ctinfo,
820                          unsigned char **data, int dataoff,
821                          Setup_UUIE *setup)
822 {
823         int dir = CTINFO2DIR(ctinfo);
824         int ret;
825         int i;
826         __be16 port;
827         union nf_conntrack_address addr;
828         typeof(set_h225_addr_hook) set_h225_addr;
829
830         DEBUGP("nf_ct_q931: Setup\n");
831
832         if (setup->options & eSetup_UUIE_h245Address) {
833                 ret = expect_h245(pskb, ct, ctinfo, data, dataoff,
834                                   &setup->h245Address);
835                 if (ret < 0)
836                         return -1;
837         }
838
839         set_h225_addr = rcu_dereference(set_h225_addr_hook);
840         if ((setup->options & eSetup_UUIE_destCallSignalAddress) &&
841             (set_h225_addr) && ct->status && IPS_NAT_MASK &&
842             get_h225_addr(ct, *data, &setup->destCallSignalAddress,
843                           &addr, &port) &&
844             memcmp(&addr, &ct->tuplehash[!dir].tuple.src.u3, sizeof(addr))) {
845                 DEBUGP("nf_ct_q931: set destCallSignalAddress "
846                        NIP6_FMT ":%hu->" NIP6_FMT ":%hu\n",
847                        NIP6(*(struct in6_addr *)&addr), ntohs(port),
848                        NIP6(*(struct in6_addr *)&ct->tuplehash[!dir].tuple.src.u3),
849                        ntohs(ct->tuplehash[!dir].tuple.src.u.tcp.port));
850                 ret = set_h225_addr(pskb, data, dataoff,
851                                     &setup->destCallSignalAddress,
852                                     &ct->tuplehash[!dir].tuple.src.u3,
853                                     ct->tuplehash[!dir].tuple.src.u.tcp.port);
854                 if (ret < 0)
855                         return -1;
856         }
857
858         if ((setup->options & eSetup_UUIE_sourceCallSignalAddress) &&
859             (set_h225_addr) && ct->status & IPS_NAT_MASK &&
860             get_h225_addr(ct, *data, &setup->sourceCallSignalAddress,
861                           &addr, &port) &&
862             memcmp(&addr, &ct->tuplehash[!dir].tuple.dst.u3, sizeof(addr))) {
863                 DEBUGP("nf_ct_q931: set sourceCallSignalAddress "
864                        NIP6_FMT ":%hu->" NIP6_FMT ":%hu\n",
865                        NIP6(*(struct in6_addr *)&addr), ntohs(port),
866                        NIP6(*(struct in6_addr *)&ct->tuplehash[!dir].tuple.dst.u3),
867                        ntohs(ct->tuplehash[!dir].tuple.dst.u.tcp.port));
868                 ret = set_h225_addr(pskb, data, dataoff,
869                                     &setup->sourceCallSignalAddress,
870                                     &ct->tuplehash[!dir].tuple.dst.u3,
871                                     ct->tuplehash[!dir].tuple.dst.u.tcp.port);
872                 if (ret < 0)
873                         return -1;
874         }
875
876         if (setup->options & eSetup_UUIE_fastStart) {
877                 for (i = 0; i < setup->fastStart.count; i++) {
878                         ret = process_olc(pskb, ct, ctinfo, data, dataoff,
879                                           &setup->fastStart.item[i]);
880                         if (ret < 0)
881                                 return -1;
882                 }
883         }
884
885         return 0;
886 }
887
888 /****************************************************************************/
889 static int process_callproceeding(struct sk_buff **pskb,
890                                   struct nf_conn *ct,
891                                   enum ip_conntrack_info ctinfo,
892                                   unsigned char **data, int dataoff,
893                                   CallProceeding_UUIE *callproc)
894 {
895         int ret;
896         int i;
897
898         DEBUGP("nf_ct_q931: CallProceeding\n");
899
900         if (callproc->options & eCallProceeding_UUIE_h245Address) {
901                 ret = expect_h245(pskb, ct, ctinfo, data, dataoff,
902                                   &callproc->h245Address);
903                 if (ret < 0)
904                         return -1;
905         }
906
907         if (callproc->options & eCallProceeding_UUIE_fastStart) {
908                 for (i = 0; i < callproc->fastStart.count; i++) {
909                         ret = process_olc(pskb, ct, ctinfo, data, dataoff,
910                                           &callproc->fastStart.item[i]);
911                         if (ret < 0)
912                                 return -1;
913                 }
914         }
915
916         return 0;
917 }
918
919 /****************************************************************************/
920 static int process_connect(struct sk_buff **pskb, struct nf_conn *ct,
921                            enum ip_conntrack_info ctinfo,
922                            unsigned char **data, int dataoff,
923                            Connect_UUIE *connect)
924 {
925         int ret;
926         int i;
927
928         DEBUGP("nf_ct_q931: Connect\n");
929
930         if (connect->options & eConnect_UUIE_h245Address) {
931                 ret = expect_h245(pskb, ct, ctinfo, data, dataoff,
932                                   &connect->h245Address);
933                 if (ret < 0)
934                         return -1;
935         }
936
937         if (connect->options & eConnect_UUIE_fastStart) {
938                 for (i = 0; i < connect->fastStart.count; i++) {
939                         ret = process_olc(pskb, ct, ctinfo, data, dataoff,
940                                           &connect->fastStart.item[i]);
941                         if (ret < 0)
942                                 return -1;
943                 }
944         }
945
946         return 0;
947 }
948
949 /****************************************************************************/
950 static int process_alerting(struct sk_buff **pskb, struct nf_conn *ct,
951                             enum ip_conntrack_info ctinfo,
952                             unsigned char **data, int dataoff,
953                             Alerting_UUIE *alert)
954 {
955         int ret;
956         int i;
957
958         DEBUGP("nf_ct_q931: Alerting\n");
959
960         if (alert->options & eAlerting_UUIE_h245Address) {
961                 ret = expect_h245(pskb, ct, ctinfo, data, dataoff,
962                                   &alert->h245Address);
963                 if (ret < 0)
964                         return -1;
965         }
966
967         if (alert->options & eAlerting_UUIE_fastStart) {
968                 for (i = 0; i < alert->fastStart.count; i++) {
969                         ret = process_olc(pskb, ct, ctinfo, data, dataoff,
970                                           &alert->fastStart.item[i]);
971                         if (ret < 0)
972                                 return -1;
973                 }
974         }
975
976         return 0;
977 }
978
979 /****************************************************************************/
980 static int process_information(struct sk_buff **pskb,
981                                struct nf_conn *ct,
982                                enum ip_conntrack_info ctinfo,
983                                unsigned char **data, int dataoff,
984                                Information_UUIE *info)
985 {
986         int ret;
987         int i;
988
989         DEBUGP("nf_ct_q931: Information\n");
990
991         if (info->options & eInformation_UUIE_fastStart) {
992                 for (i = 0; i < info->fastStart.count; i++) {
993                         ret = process_olc(pskb, ct, ctinfo, data, dataoff,
994                                           &info->fastStart.item[i]);
995                         if (ret < 0)
996                                 return -1;
997                 }
998         }
999
1000         return 0;
1001 }
1002
1003 /****************************************************************************/
1004 static int process_facility(struct sk_buff **pskb, struct nf_conn *ct,
1005                             enum ip_conntrack_info ctinfo,
1006                             unsigned char **data, int dataoff,
1007                             Facility_UUIE *facility)
1008 {
1009         int ret;
1010         int i;
1011
1012         DEBUGP("nf_ct_q931: Facility\n");
1013
1014         if (facility->reason.choice == eFacilityReason_callForwarded) {
1015                 if (facility->options & eFacility_UUIE_alternativeAddress)
1016                         return expect_callforwarding(pskb, ct, ctinfo, data,
1017                                                      dataoff,
1018                                                      &facility->
1019                                                      alternativeAddress);
1020                 return 0;
1021         }
1022
1023         if (facility->options & eFacility_UUIE_h245Address) {
1024                 ret = expect_h245(pskb, ct, ctinfo, data, dataoff,
1025                                   &facility->h245Address);
1026                 if (ret < 0)
1027                         return -1;
1028         }
1029
1030         if (facility->options & eFacility_UUIE_fastStart) {
1031                 for (i = 0; i < facility->fastStart.count; i++) {
1032                         ret = process_olc(pskb, ct, ctinfo, data, dataoff,
1033                                           &facility->fastStart.item[i]);
1034                         if (ret < 0)
1035                                 return -1;
1036                 }
1037         }
1038
1039         return 0;
1040 }
1041
1042 /****************************************************************************/
1043 static int process_progress(struct sk_buff **pskb, struct nf_conn *ct,
1044                             enum ip_conntrack_info ctinfo,
1045                             unsigned char **data, int dataoff,
1046                             Progress_UUIE *progress)
1047 {
1048         int ret;
1049         int i;
1050
1051         DEBUGP("nf_ct_q931: Progress\n");
1052
1053         if (progress->options & eProgress_UUIE_h245Address) {
1054                 ret = expect_h245(pskb, ct, ctinfo, data, dataoff,
1055                                   &progress->h245Address);
1056                 if (ret < 0)
1057                         return -1;
1058         }
1059
1060         if (progress->options & eProgress_UUIE_fastStart) {
1061                 for (i = 0; i < progress->fastStart.count; i++) {
1062                         ret = process_olc(pskb, ct, ctinfo, data, dataoff,
1063                                           &progress->fastStart.item[i]);
1064                         if (ret < 0)
1065                                 return -1;
1066                 }
1067         }
1068
1069         return 0;
1070 }
1071
1072 /****************************************************************************/
1073 static int process_q931(struct sk_buff **pskb, struct nf_conn *ct,
1074                         enum ip_conntrack_info ctinfo,
1075                         unsigned char **data, int dataoff, Q931 *q931)
1076 {
1077         H323_UU_PDU *pdu = &q931->UUIE.h323_uu_pdu;
1078         int i;
1079         int ret = 0;
1080
1081         switch (pdu->h323_message_body.choice) {
1082         case eH323_UU_PDU_h323_message_body_setup:
1083                 ret = process_setup(pskb, ct, ctinfo, data, dataoff,
1084                                     &pdu->h323_message_body.setup);
1085                 break;
1086         case eH323_UU_PDU_h323_message_body_callProceeding:
1087                 ret = process_callproceeding(pskb, ct, ctinfo, data, dataoff,
1088                                              &pdu->h323_message_body.
1089                                              callProceeding);
1090                 break;
1091         case eH323_UU_PDU_h323_message_body_connect:
1092                 ret = process_connect(pskb, ct, ctinfo, data, dataoff,
1093                                       &pdu->h323_message_body.connect);
1094                 break;
1095         case eH323_UU_PDU_h323_message_body_alerting:
1096                 ret = process_alerting(pskb, ct, ctinfo, data, dataoff,
1097                                        &pdu->h323_message_body.alerting);
1098                 break;
1099         case eH323_UU_PDU_h323_message_body_information:
1100                 ret = process_information(pskb, ct, ctinfo, data, dataoff,
1101                                           &pdu->h323_message_body.
1102                                           information);
1103                 break;
1104         case eH323_UU_PDU_h323_message_body_facility:
1105                 ret = process_facility(pskb, ct, ctinfo, data, dataoff,
1106                                        &pdu->h323_message_body.facility);
1107                 break;
1108         case eH323_UU_PDU_h323_message_body_progress:
1109                 ret = process_progress(pskb, ct, ctinfo, data, dataoff,
1110                                        &pdu->h323_message_body.progress);
1111                 break;
1112         default:
1113                 DEBUGP("nf_ct_q931: Q.931 signal %d\n",
1114                        pdu->h323_message_body.choice);
1115                 break;
1116         }
1117
1118         if (ret < 0)
1119                 return -1;
1120
1121         if (pdu->options & eH323_UU_PDU_h245Control) {
1122                 for (i = 0; i < pdu->h245Control.count; i++) {
1123                         ret = process_h245(pskb, ct, ctinfo, data, dataoff,
1124                                            &pdu->h245Control.item[i]);
1125                         if (ret < 0)
1126                                 return -1;
1127                 }
1128         }
1129
1130         return 0;
1131 }
1132
1133 /****************************************************************************/
1134 static int q931_help(struct sk_buff **pskb, unsigned int protoff,
1135                      struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1136 {
1137         static Q931 q931;
1138         unsigned char *data = NULL;
1139         int datalen;
1140         int dataoff;
1141         int ret;
1142
1143         /* Until there's been traffic both ways, don't look in packets. */
1144         if (ctinfo != IP_CT_ESTABLISHED &&
1145             ctinfo != IP_CT_ESTABLISHED + IP_CT_IS_REPLY) {
1146                 return NF_ACCEPT;
1147         }
1148         DEBUGP("nf_ct_q931: skblen = %u\n", (*pskb)->len);
1149
1150         spin_lock_bh(&nf_h323_lock);
1151
1152         /* Process each TPKT */
1153         while (get_tpkt_data(pskb, protoff, ct, ctinfo,
1154                              &data, &datalen, &dataoff)) {
1155                 DEBUGP("nf_ct_q931: TPKT len=%d ", datalen);
1156                 NF_CT_DUMP_TUPLE(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1157
1158                 /* Decode Q.931 signal */
1159                 ret = DecodeQ931(data, datalen, &q931);
1160                 if (ret < 0) {
1161                         if (net_ratelimit())
1162                                 printk("nf_ct_q931: decoding error: %s\n",
1163                                        ret == H323_ERROR_BOUND ?
1164                                        "out of bound" : "out of range");
1165                         /* We don't drop when decoding error */
1166                         break;
1167                 }
1168
1169                 /* Process Q.931 signal */
1170                 if (process_q931(pskb, ct, ctinfo, &data, dataoff, &q931) < 0)
1171                         goto drop;
1172         }
1173
1174         spin_unlock_bh(&nf_h323_lock);
1175         return NF_ACCEPT;
1176
1177       drop:
1178         spin_unlock_bh(&nf_h323_lock);
1179         if (net_ratelimit())
1180                 printk("nf_ct_q931: packet dropped\n");
1181         return NF_DROP;
1182 }
1183
1184 /****************************************************************************/
1185 static struct nf_conntrack_helper nf_conntrack_helper_q931[] __read_mostly = {
1186         {
1187                 .name                   = "Q.931",
1188                 .me                     = THIS_MODULE,
1189                                           /* T.120 and H.245 */
1190                 .max_expected           = H323_RTP_CHANNEL_MAX * 4 + 4,
1191                 .timeout                = 240,
1192                 .tuple.src.l3num        = AF_INET,
1193                 .tuple.src.u.tcp.port   = __constant_htons(Q931_PORT),
1194                 .tuple.dst.protonum     = IPPROTO_TCP,
1195                 .mask.src.l3num         = 0xFFFF,
1196                 .mask.src.u.tcp.port    = __constant_htons(0xFFFF),
1197                 .mask.dst.protonum      = 0xFF,
1198                 .help                   = q931_help
1199         },
1200         {
1201                 .name                   = "Q.931",
1202                 .me                     = THIS_MODULE,
1203                                           /* T.120 and H.245 */
1204                 .max_expected           = H323_RTP_CHANNEL_MAX * 4 + 4,
1205                 .timeout                = 240,
1206                 .tuple.src.l3num        = AF_INET6,
1207                 .tuple.src.u.tcp.port   = __constant_htons(Q931_PORT),
1208                 .tuple.dst.protonum     = IPPROTO_TCP,
1209                 .mask.src.l3num         = 0xFFFF,
1210                 .mask.src.u.tcp.port    = __constant_htons(0xFFFF),
1211                 .mask.dst.protonum      = 0xFF,
1212                 .help                   = q931_help
1213         },
1214 };
1215
1216 /****************************************************************************/
1217 static unsigned char *get_udp_data(struct sk_buff **pskb, unsigned int protoff,
1218                                    int *datalen)
1219 {
1220         struct udphdr _uh, *uh;
1221         int dataoff;
1222
1223         uh = skb_header_pointer(*pskb, protoff, sizeof(_uh), &_uh);
1224         if (uh == NULL)
1225                 return NULL;
1226         dataoff = protoff + sizeof(_uh);
1227         if (dataoff >= (*pskb)->len)
1228                 return NULL;
1229         *datalen = (*pskb)->len - dataoff;
1230         return skb_header_pointer(*pskb, dataoff, *datalen, h323_buffer);
1231 }
1232
1233 /****************************************************************************/
1234 static struct nf_conntrack_expect *find_expect(struct nf_conn *ct,
1235                                                union nf_conntrack_address *addr,
1236                                                __be16 port)
1237 {
1238         struct nf_conntrack_expect *exp;
1239         struct nf_conntrack_tuple tuple;
1240
1241         memset(&tuple.src.u3, 0, sizeof(tuple.src.u3));
1242         tuple.src.u.tcp.port = 0;
1243         memcpy(&tuple.dst.u3, addr, sizeof(tuple.dst.u3));
1244         tuple.dst.u.tcp.port = port;
1245         tuple.dst.protonum = IPPROTO_TCP;
1246
1247         exp = __nf_conntrack_expect_find(&tuple);
1248         if (exp && exp->master == ct)
1249                 return exp;
1250         return NULL;
1251 }
1252
1253 /****************************************************************************/
1254 static int set_expect_timeout(struct nf_conntrack_expect *exp,
1255                               unsigned timeout)
1256 {
1257         if (!exp || !del_timer(&exp->timeout))
1258                 return 0;
1259
1260         exp->timeout.expires = jiffies + timeout * HZ;
1261         add_timer(&exp->timeout);
1262
1263         return 1;
1264 }
1265
1266 /****************************************************************************/
1267 static int expect_q931(struct sk_buff **pskb, struct nf_conn *ct,
1268                        enum ip_conntrack_info ctinfo,
1269                        unsigned char **data,
1270                        TransportAddress *taddr, int count)
1271 {
1272         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1273         int dir = CTINFO2DIR(ctinfo);
1274         int ret = 0;
1275         int i;
1276         __be16 port;
1277         union nf_conntrack_address addr;
1278         struct nf_conntrack_expect *exp;
1279         typeof(nat_q931_hook) nat_q931;
1280
1281         /* Look for the first related address */
1282         for (i = 0; i < count; i++) {
1283                 if (get_h225_addr(ct, *data, &taddr[i], &addr, &port) &&
1284                     memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3,
1285                            sizeof(addr)) == 0 && port != 0)
1286                         break;
1287         }
1288
1289         if (i >= count)         /* Not found */
1290                 return 0;
1291
1292         /* Create expect for Q.931 */
1293         if ((exp = nf_conntrack_expect_alloc(ct)) == NULL)
1294                 return -1;
1295         nf_conntrack_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num,
1296                                  gkrouted_only ? /* only accept calls from GK? */
1297                                         &ct->tuplehash[!dir].tuple.src.u3 :
1298                                         NULL,
1299                                  &ct->tuplehash[!dir].tuple.dst.u3,
1300                                  IPPROTO_TCP, NULL, &port);
1301         exp->helper = nf_conntrack_helper_q931;
1302         exp->flags = NF_CT_EXPECT_PERMANENT;    /* Accept multiple calls */
1303
1304         nat_q931 = rcu_dereference(nat_q931_hook);
1305         if (nat_q931 && ct->status & IPS_NAT_MASK) {    /* Need NAT */
1306                 ret = nat_q931(pskb, ct, ctinfo, data, taddr, i, port, exp);
1307         } else {                /* Conntrack only */
1308                 if (nf_conntrack_expect_related(exp) == 0) {
1309                         DEBUGP("nf_ct_ras: expect Q.931 ");
1310                         NF_CT_DUMP_TUPLE(&exp->tuple);
1311
1312                         /* Save port for looking up expect in processing RCF */
1313                         info->sig_port[dir] = port;
1314                 } else
1315                         ret = -1;
1316         }
1317
1318         nf_conntrack_expect_put(exp);
1319
1320         return ret;
1321 }
1322
1323 /****************************************************************************/
1324 static int process_grq(struct sk_buff **pskb, struct nf_conn *ct,
1325                        enum ip_conntrack_info ctinfo,
1326                        unsigned char **data, GatekeeperRequest *grq)
1327 {
1328         typeof(set_ras_addr_hook) set_ras_addr;
1329
1330         DEBUGP("nf_ct_ras: GRQ\n");
1331
1332         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1333         if (set_ras_addr && ct->status & IPS_NAT_MASK)  /* NATed */
1334                 return set_ras_addr(pskb, ct, ctinfo, data,
1335                                     &grq->rasAddress, 1);
1336         return 0;
1337 }
1338
1339 /****************************************************************************/
1340 static int process_gcf(struct sk_buff **pskb, struct nf_conn *ct,
1341                        enum ip_conntrack_info ctinfo,
1342                        unsigned char **data, GatekeeperConfirm *gcf)
1343 {
1344         int dir = CTINFO2DIR(ctinfo);
1345         int ret = 0;
1346         __be16 port;
1347         union nf_conntrack_address addr;
1348         struct nf_conntrack_expect *exp;
1349
1350         DEBUGP("nf_ct_ras: GCF\n");
1351
1352         if (!get_h225_addr(ct, *data, &gcf->rasAddress, &addr, &port))
1353                 return 0;
1354
1355         /* Registration port is the same as discovery port */
1356         if (!memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1357             port == ct->tuplehash[dir].tuple.src.u.udp.port)
1358                 return 0;
1359
1360         /* Avoid RAS expectation loops. A GCF is never expected. */
1361         if (test_bit(IPS_EXPECTED_BIT, &ct->status))
1362                 return 0;
1363
1364         /* Need new expect */
1365         if ((exp = nf_conntrack_expect_alloc(ct)) == NULL)
1366                 return -1;
1367         nf_conntrack_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num,
1368                                  &ct->tuplehash[!dir].tuple.src.u3, &addr,
1369                                  IPPROTO_UDP, NULL, &port);
1370         exp->helper = nf_conntrack_helper_ras;
1371
1372         if (nf_conntrack_expect_related(exp) == 0) {
1373                 DEBUGP("nf_ct_ras: expect RAS ");
1374                 NF_CT_DUMP_TUPLE(&exp->tuple);
1375         } else
1376                 ret = -1;
1377
1378         nf_conntrack_expect_put(exp);
1379
1380         return ret;
1381 }
1382
1383 /****************************************************************************/
1384 static int process_rrq(struct sk_buff **pskb, struct nf_conn *ct,
1385                        enum ip_conntrack_info ctinfo,
1386                        unsigned char **data, RegistrationRequest *rrq)
1387 {
1388         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1389         int ret;
1390         typeof(set_ras_addr_hook) set_ras_addr;
1391
1392         DEBUGP("nf_ct_ras: RRQ\n");
1393
1394         ret = expect_q931(pskb, ct, ctinfo, data,
1395                           rrq->callSignalAddress.item,
1396                           rrq->callSignalAddress.count);
1397         if (ret < 0)
1398                 return -1;
1399
1400         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1401         if (set_ras_addr && ct->status & IPS_NAT_MASK) {
1402                 ret = set_ras_addr(pskb, ct, ctinfo, data,
1403                                    rrq->rasAddress.item,
1404                                    rrq->rasAddress.count);
1405                 if (ret < 0)
1406                         return -1;
1407         }
1408
1409         if (rrq->options & eRegistrationRequest_timeToLive) {
1410                 DEBUGP("nf_ct_ras: RRQ TTL = %u seconds\n", rrq->timeToLive);
1411                 info->timeout = rrq->timeToLive;
1412         } else
1413                 info->timeout = default_rrq_ttl;
1414
1415         return 0;
1416 }
1417
1418 /****************************************************************************/
1419 static int process_rcf(struct sk_buff **pskb, struct nf_conn *ct,
1420                        enum ip_conntrack_info ctinfo,
1421                        unsigned char **data, RegistrationConfirm *rcf)
1422 {
1423         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1424         int dir = CTINFO2DIR(ctinfo);
1425         int ret;
1426         struct nf_conntrack_expect *exp;
1427         typeof(set_sig_addr_hook) set_sig_addr;
1428
1429         DEBUGP("nf_ct_ras: RCF\n");
1430
1431         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1432         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1433                 ret = set_sig_addr(pskb, ct, ctinfo, data,
1434                                         rcf->callSignalAddress.item,
1435                                         rcf->callSignalAddress.count);
1436                 if (ret < 0)
1437                         return -1;
1438         }
1439
1440         if (rcf->options & eRegistrationConfirm_timeToLive) {
1441                 DEBUGP("nf_ct_ras: RCF TTL = %u seconds\n", rcf->timeToLive);
1442                 info->timeout = rcf->timeToLive;
1443         }
1444
1445         if (info->timeout > 0) {
1446                 DEBUGP
1447                     ("nf_ct_ras: set RAS connection timeout to %u seconds\n",
1448                      info->timeout);
1449                 nf_ct_refresh(ct, *pskb, info->timeout * HZ);
1450
1451                 /* Set expect timeout */
1452                 read_lock_bh(&nf_conntrack_lock);
1453                 exp = find_expect(ct, &ct->tuplehash[dir].tuple.dst.u3,
1454                                   info->sig_port[!dir]);
1455                 if (exp) {
1456                         DEBUGP("nf_ct_ras: set Q.931 expect "
1457                                "timeout to %u seconds for",
1458                                info->timeout);
1459                         NF_CT_DUMP_TUPLE(&exp->tuple);
1460                         set_expect_timeout(exp, info->timeout);
1461                 }
1462                 read_unlock_bh(&nf_conntrack_lock);
1463         }
1464
1465         return 0;
1466 }
1467
1468 /****************************************************************************/
1469 static int process_urq(struct sk_buff **pskb, struct nf_conn *ct,
1470                        enum ip_conntrack_info ctinfo,
1471                        unsigned char **data, UnregistrationRequest *urq)
1472 {
1473         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1474         int dir = CTINFO2DIR(ctinfo);
1475         int ret;
1476         typeof(set_sig_addr_hook) set_sig_addr;
1477
1478         DEBUGP("nf_ct_ras: URQ\n");
1479
1480         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1481         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1482                 ret = set_sig_addr(pskb, ct, ctinfo, data,
1483                                    urq->callSignalAddress.item,
1484                                    urq->callSignalAddress.count);
1485                 if (ret < 0)
1486                         return -1;
1487         }
1488
1489         /* Clear old expect */
1490         nf_ct_remove_expectations(ct);
1491         info->sig_port[dir] = 0;
1492         info->sig_port[!dir] = 0;
1493
1494         /* Give it 30 seconds for UCF or URJ */
1495         nf_ct_refresh(ct, *pskb, 30 * HZ);
1496
1497         return 0;
1498 }
1499
1500 /****************************************************************************/
1501 static int process_arq(struct sk_buff **pskb, struct nf_conn *ct,
1502                        enum ip_conntrack_info ctinfo,
1503                        unsigned char **data, AdmissionRequest *arq)
1504 {
1505         struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1506         int dir = CTINFO2DIR(ctinfo);
1507         __be16 port;
1508         union nf_conntrack_address addr;
1509         typeof(set_h225_addr_hook) set_h225_addr;
1510
1511         DEBUGP("nf_ct_ras: ARQ\n");
1512
1513         set_h225_addr = rcu_dereference(set_h225_addr_hook);
1514         if ((arq->options & eAdmissionRequest_destCallSignalAddress) &&
1515             get_h225_addr(ct, *data, &arq->destCallSignalAddress,
1516                           &addr, &port) &&
1517             !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1518             port == info->sig_port[dir] &&
1519             set_h225_addr && ct->status & IPS_NAT_MASK) {
1520                 /* Answering ARQ */
1521                 return set_h225_addr(pskb, data, 0,
1522                                      &arq->destCallSignalAddress,
1523                                      &ct->tuplehash[!dir].tuple.dst.u3,
1524                                      info->sig_port[!dir]);
1525         }
1526
1527         if ((arq->options & eAdmissionRequest_srcCallSignalAddress) &&
1528             get_h225_addr(ct, *data, &arq->srcCallSignalAddress,
1529                           &addr, &port) &&
1530             !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1531             set_h225_addr && ct->status & IPS_NAT_MASK) {
1532                 /* Calling ARQ */
1533                 return set_h225_addr(pskb, data, 0,
1534                                      &arq->srcCallSignalAddress,
1535                                      &ct->tuplehash[!dir].tuple.dst.u3,
1536                                      port);
1537         }
1538
1539         return 0;
1540 }
1541
1542 /****************************************************************************/
1543 static int process_acf(struct sk_buff **pskb, struct nf_conn *ct,
1544                        enum ip_conntrack_info ctinfo,
1545                        unsigned char **data, AdmissionConfirm *acf)
1546 {
1547         int dir = CTINFO2DIR(ctinfo);
1548         int ret = 0;
1549         __be16 port;
1550         union nf_conntrack_address addr;
1551         struct nf_conntrack_expect *exp;
1552         typeof(set_sig_addr_hook) set_sig_addr;
1553
1554         DEBUGP("nf_ct_ras: ACF\n");
1555
1556         if (!get_h225_addr(ct, *data, &acf->destCallSignalAddress,
1557                            &addr, &port))
1558                 return 0;
1559
1560         if (!memcmp(&addr, &ct->tuplehash[dir].tuple.dst.u3, sizeof(addr))) {
1561                 /* Answering ACF */
1562                 set_sig_addr = rcu_dereference(set_sig_addr_hook);
1563                 if (set_sig_addr && ct->status & IPS_NAT_MASK)
1564                         return set_sig_addr(pskb, ct, ctinfo, data,
1565                                             &acf->destCallSignalAddress, 1);
1566                 return 0;
1567         }
1568
1569         /* Need new expect */
1570         if ((exp = nf_conntrack_expect_alloc(ct)) == NULL)
1571                 return -1;
1572         nf_conntrack_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num,
1573                                  &ct->tuplehash[!dir].tuple.src.u3, &addr,
1574                                  IPPROTO_TCP, NULL, &port);
1575         exp->flags = NF_CT_EXPECT_PERMANENT;
1576         exp->helper = nf_conntrack_helper_q931;
1577
1578         if (nf_conntrack_expect_related(exp) == 0) {
1579                 DEBUGP("nf_ct_ras: expect Q.931 ");
1580                 NF_CT_DUMP_TUPLE(&exp->tuple);
1581         } else
1582                 ret = -1;
1583
1584         nf_conntrack_expect_put(exp);
1585
1586         return ret;
1587 }
1588
1589 /****************************************************************************/
1590 static int process_lrq(struct sk_buff **pskb, struct nf_conn *ct,
1591                        enum ip_conntrack_info ctinfo,
1592                        unsigned char **data, LocationRequest *lrq)
1593 {
1594         typeof(set_ras_addr_hook) set_ras_addr;
1595
1596         DEBUGP("nf_ct_ras: LRQ\n");
1597
1598         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1599         if (set_ras_addr && ct->status & IPS_NAT_MASK)
1600                 return set_ras_addr(pskb, ct, ctinfo, data,
1601                                     &lrq->replyAddress, 1);
1602         return 0;
1603 }
1604
1605 /****************************************************************************/
1606 static int process_lcf(struct sk_buff **pskb, struct nf_conn *ct,
1607                        enum ip_conntrack_info ctinfo,
1608                        unsigned char **data, LocationConfirm *lcf)
1609 {
1610         int dir = CTINFO2DIR(ctinfo);
1611         int ret = 0;
1612         __be16 port;
1613         union nf_conntrack_address addr;
1614         struct nf_conntrack_expect *exp;
1615
1616         DEBUGP("nf_ct_ras: LCF\n");
1617
1618         if (!get_h225_addr(ct, *data, &lcf->callSignalAddress,
1619                            &addr, &port))
1620                 return 0;
1621
1622         /* Need new expect for call signal */
1623         if ((exp = nf_conntrack_expect_alloc(ct)) == NULL)
1624                 return -1;
1625         nf_conntrack_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num,
1626                                  &ct->tuplehash[!dir].tuple.src.u3, &addr,
1627                                  IPPROTO_TCP, NULL, &port);
1628         exp->flags = NF_CT_EXPECT_PERMANENT;
1629         exp->helper = nf_conntrack_helper_q931;
1630
1631         if (nf_conntrack_expect_related(exp) == 0) {
1632                 DEBUGP("nf_ct_ras: expect Q.931 ");
1633                 NF_CT_DUMP_TUPLE(&exp->tuple);
1634         } else
1635                 ret = -1;
1636
1637         nf_conntrack_expect_put(exp);
1638
1639         /* Ignore rasAddress */
1640
1641         return ret;
1642 }
1643
1644 /****************************************************************************/
1645 static int process_irr(struct sk_buff **pskb, struct nf_conn *ct,
1646                        enum ip_conntrack_info ctinfo,
1647                        unsigned char **data, InfoRequestResponse *irr)
1648 {
1649         int ret;
1650         typeof(set_ras_addr_hook) set_ras_addr;
1651         typeof(set_sig_addr_hook) set_sig_addr;
1652
1653         DEBUGP("nf_ct_ras: IRR\n");
1654
1655         set_ras_addr = rcu_dereference(set_ras_addr_hook);
1656         if (set_ras_addr && ct->status & IPS_NAT_MASK) {
1657                 ret = set_ras_addr(pskb, ct, ctinfo, data,
1658                                    &irr->rasAddress, 1);
1659                 if (ret < 0)
1660                         return -1;
1661         }
1662
1663         set_sig_addr = rcu_dereference(set_sig_addr_hook);
1664         if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1665                 ret = set_sig_addr(pskb, ct, ctinfo, data,
1666                                         irr->callSignalAddress.item,
1667                                         irr->callSignalAddress.count);
1668                 if (ret < 0)
1669                         return -1;
1670         }
1671
1672         return 0;
1673 }
1674
1675 /****************************************************************************/
1676 static int process_ras(struct sk_buff **pskb, struct nf_conn *ct,
1677                        enum ip_conntrack_info ctinfo,
1678                        unsigned char **data, RasMessage *ras)
1679 {
1680         switch (ras->choice) {
1681         case eRasMessage_gatekeeperRequest:
1682                 return process_grq(pskb, ct, ctinfo, data,
1683                                    &ras->gatekeeperRequest);
1684         case eRasMessage_gatekeeperConfirm:
1685                 return process_gcf(pskb, ct, ctinfo, data,
1686                                    &ras->gatekeeperConfirm);
1687         case eRasMessage_registrationRequest:
1688                 return process_rrq(pskb, ct, ctinfo, data,
1689                                    &ras->registrationRequest);
1690         case eRasMessage_registrationConfirm:
1691                 return process_rcf(pskb, ct, ctinfo, data,
1692                                    &ras->registrationConfirm);
1693         case eRasMessage_unregistrationRequest:
1694                 return process_urq(pskb, ct, ctinfo, data,
1695                                    &ras->unregistrationRequest);
1696         case eRasMessage_admissionRequest:
1697                 return process_arq(pskb, ct, ctinfo, data,
1698                                    &ras->admissionRequest);
1699         case eRasMessage_admissionConfirm:
1700                 return process_acf(pskb, ct, ctinfo, data,
1701                                    &ras->admissionConfirm);
1702         case eRasMessage_locationRequest:
1703                 return process_lrq(pskb, ct, ctinfo, data,
1704                                    &ras->locationRequest);
1705         case eRasMessage_locationConfirm:
1706                 return process_lcf(pskb, ct, ctinfo, data,
1707                                    &ras->locationConfirm);
1708         case eRasMessage_infoRequestResponse:
1709                 return process_irr(pskb, ct, ctinfo, data,
1710                                    &ras->infoRequestResponse);
1711         default:
1712                 DEBUGP("nf_ct_ras: RAS message %d\n", ras->choice);
1713                 break;
1714         }
1715
1716         return 0;
1717 }
1718
1719 /****************************************************************************/
1720 static int ras_help(struct sk_buff **pskb, unsigned int protoff,
1721                     struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1722 {
1723         static RasMessage ras;
1724         unsigned char *data;
1725         int datalen = 0;
1726         int ret;
1727
1728         DEBUGP("nf_ct_ras: skblen = %u\n", (*pskb)->len);
1729
1730         spin_lock_bh(&nf_h323_lock);
1731
1732         /* Get UDP data */
1733         data = get_udp_data(pskb, protoff, &datalen);
1734         if (data == NULL)
1735                 goto accept;
1736         DEBUGP("nf_ct_ras: RAS message len=%d ", datalen);
1737         NF_CT_DUMP_TUPLE(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1738
1739         /* Decode RAS message */
1740         ret = DecodeRasMessage(data, datalen, &ras);
1741         if (ret < 0) {
1742                 if (net_ratelimit())
1743                         printk("nf_ct_ras: decoding error: %s\n",
1744                                ret == H323_ERROR_BOUND ?
1745                                "out of bound" : "out of range");
1746                 goto accept;
1747         }
1748
1749         /* Process RAS message */
1750         if (process_ras(pskb, ct, ctinfo, &data, &ras) < 0)
1751                 goto drop;
1752
1753       accept:
1754         spin_unlock_bh(&nf_h323_lock);
1755         return NF_ACCEPT;
1756
1757       drop:
1758         spin_unlock_bh(&nf_h323_lock);
1759         if (net_ratelimit())
1760                 printk("nf_ct_ras: packet dropped\n");
1761         return NF_DROP;
1762 }
1763
1764 /****************************************************************************/
1765 static struct nf_conntrack_helper nf_conntrack_helper_ras[] __read_mostly = {
1766         {
1767                 .name                   = "RAS",
1768                 .me                     = THIS_MODULE,
1769                 .max_expected           = 32,
1770                 .timeout                = 240,
1771                 .tuple.src.l3num        = AF_INET,
1772                 .tuple.src.u.udp.port   = __constant_htons(RAS_PORT),
1773                 .tuple.dst.protonum     = IPPROTO_UDP,
1774                 .mask.src.l3num         = 0xFFFF,
1775                 .mask.src.u.udp.port    = __constant_htons(0xFFFF),
1776                 .mask.dst.protonum      = 0xFF,
1777                 .help                   = ras_help,
1778         },
1779         {
1780                 .name                   = "RAS",
1781                 .me                     = THIS_MODULE,
1782                 .max_expected           = 32,
1783                 .timeout                = 240,
1784                 .tuple.src.l3num        = AF_INET6,
1785                 .tuple.src.u.udp.port   = __constant_htons(RAS_PORT),
1786                 .tuple.dst.protonum     = IPPROTO_UDP,
1787                 .mask.src.l3num         = 0xFFFF,
1788                 .mask.src.u.udp.port    = __constant_htons(0xFFFF),
1789                 .mask.dst.protonum      = 0xFF,
1790                 .help                   = ras_help,
1791         },
1792 };
1793
1794 /****************************************************************************/
1795 static void __exit nf_conntrack_h323_fini(void)
1796 {
1797         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[1]);
1798         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1799         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1800         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1801         kfree(h323_buffer);
1802         DEBUGP("nf_ct_h323: fini\n");
1803 }
1804
1805 /****************************************************************************/
1806 static int __init nf_conntrack_h323_init(void)
1807 {
1808         int ret;
1809
1810         h323_buffer = kmalloc(65536, GFP_KERNEL);
1811         if (!h323_buffer)
1812                 return -ENOMEM;
1813         ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[0]);
1814         if (ret < 0)
1815                 goto err1;
1816         ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[1]);
1817         if (ret < 0)
1818                 goto err2;
1819         ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[0]);
1820         if (ret < 0)
1821                 goto err3;
1822         ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[1]);
1823         if (ret < 0)
1824                 goto err4;
1825         DEBUGP("nf_ct_h323: init success\n");
1826         return 0;
1827
1828 err4:
1829         nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1830 err3:
1831         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1832 err2:
1833         nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1834 err1:
1835         return ret;
1836 }
1837
1838 /****************************************************************************/
1839 module_init(nf_conntrack_h323_init);
1840 module_exit(nf_conntrack_h323_fini);
1841
1842 EXPORT_SYMBOL_GPL(get_h225_addr);
1843 EXPORT_SYMBOL_GPL(set_h245_addr_hook);
1844 EXPORT_SYMBOL_GPL(set_h225_addr_hook);
1845 EXPORT_SYMBOL_GPL(set_sig_addr_hook);
1846 EXPORT_SYMBOL_GPL(set_ras_addr_hook);
1847 EXPORT_SYMBOL_GPL(nat_rtp_rtcp_hook);
1848 EXPORT_SYMBOL_GPL(nat_t120_hook);
1849 EXPORT_SYMBOL_GPL(nat_h245_hook);
1850 EXPORT_SYMBOL_GPL(nat_callforwarding_hook);
1851 EXPORT_SYMBOL_GPL(nat_q931_hook);
1852
1853 MODULE_AUTHOR("Jing Min Zhao <zhaojingmin@users.sourceforge.net>");
1854 MODULE_DESCRIPTION("H.323 connection tracking helper");
1855 MODULE_LICENSE("GPL");
1856 MODULE_ALIAS("ip_conntrack_h323");