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Merge branch 'for-2.6.40' of git://git.kernel.org/pub/scm/linux/kernel/git/oleg/misc
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / net / netfilter / nf_conntrack_h323_main.c
blob18b2ce5c8ced1c82f5f4e3f41af1ed1e659079f9
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 int callforward_filter __read_mostly = 1;
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(ct)->help.ct_h323_info;
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 port &= htons(~1);
274 rtp_port = port;
275 rtcp_port = htons(ntohs(port) + 1);
276
277 /* Create expect for RTP */
278 if ((rtp_exp = nf_ct_expect_alloc(ct)) == NULL)
279 return -1;
280 nf_ct_expect_init(rtp_exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
281 &ct->tuplehash[!dir].tuple.src.u3,
282 &ct->tuplehash[!dir].tuple.dst.u3,
283 IPPROTO_UDP, NULL, &rtp_port);
284
285 /* Create expect for RTCP */
286 if ((rtcp_exp = nf_ct_expect_alloc(ct)) == NULL) {
287 nf_ct_expect_put(rtp_exp);
288 return -1;
289 }
290 nf_ct_expect_init(rtcp_exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
291 &ct->tuplehash[!dir].tuple.src.u3,
292 &ct->tuplehash[!dir].tuple.dst.u3,
293 IPPROTO_UDP, NULL, &rtcp_port);
294
295 if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
296 &ct->tuplehash[!dir].tuple.dst.u3,
297 sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
298 (nat_rtp_rtcp = rcu_dereference(nat_rtp_rtcp_hook)) &&
299 ct->status & IPS_NAT_MASK) {
300 /* NAT needed */
301 ret = nat_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
302 taddr, port, rtp_port, rtp_exp, rtcp_exp);
303 } else { /* Conntrack only */
304 if (nf_ct_expect_related(rtp_exp) == 0) {
305 if (nf_ct_expect_related(rtcp_exp) == 0) {
306 pr_debug("nf_ct_h323: expect RTP ");
307 nf_ct_dump_tuple(&rtp_exp->tuple);
308 pr_debug("nf_ct_h323: expect RTCP ");
309 nf_ct_dump_tuple(&rtcp_exp->tuple);
310 } else {
311 nf_ct_unexpect_related(rtp_exp);
312 ret = -1;
313 }
314 } else
315 ret = -1;
316 }
317
318 nf_ct_expect_put(rtp_exp);
319 nf_ct_expect_put(rtcp_exp);
320
321 return ret;
322 }
323
324 /****************************************************************************/
325 static int expect_t120(struct sk_buff *skb,
326 struct nf_conn *ct,
327 enum ip_conntrack_info ctinfo,
328 unsigned char **data, int dataoff,
329 H245_TransportAddress *taddr)
330 {
331 int dir = CTINFO2DIR(ctinfo);
332 int ret = 0;
333 __be16 port;
334 union nf_inet_addr addr;
335 struct nf_conntrack_expect *exp;
336 typeof(nat_t120_hook) nat_t120;
337
338 /* Read T.120 address */
339 if (!get_h245_addr(ct, *data, taddr, &addr, &port) ||
340 memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
341 port == 0)
342 return 0;
343
344 /* Create expect for T.120 connections */
345 if ((exp = nf_ct_expect_alloc(ct)) == NULL)
346 return -1;
347 nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
348 &ct->tuplehash[!dir].tuple.src.u3,
349 &ct->tuplehash[!dir].tuple.dst.u3,
350 IPPROTO_TCP, NULL, &port);
351 exp->flags = NF_CT_EXPECT_PERMANENT; /* Accept multiple channels */
352
353 if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
354 &ct->tuplehash[!dir].tuple.dst.u3,
355 sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
356 (nat_t120 = rcu_dereference(nat_t120_hook)) &&
357 ct->status & IPS_NAT_MASK) {
358 /* NAT needed */
359 ret = nat_t120(skb, ct, ctinfo, data, dataoff, taddr,
360 port, exp);
361 } else { /* Conntrack only */
362 if (nf_ct_expect_related(exp) == 0) {
363 pr_debug("nf_ct_h323: expect T.120 ");
364 nf_ct_dump_tuple(&exp->tuple);
365 } else
366 ret = -1;
367 }
368
369 nf_ct_expect_put(exp);
370
371 return ret;
372 }
373
374 /****************************************************************************/
375 static int process_h245_channel(struct sk_buff *skb,
376 struct nf_conn *ct,
377 enum ip_conntrack_info ctinfo,
378 unsigned char **data, int dataoff,
379 H2250LogicalChannelParameters *channel)
380 {
381 int ret;
382
383 if (channel->options & eH2250LogicalChannelParameters_mediaChannel) {
384 /* RTP */
385 ret = expect_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
386 &channel->mediaChannel);
387 if (ret < 0)
388 return -1;
389 }
390
391 if (channel->
392 options & eH2250LogicalChannelParameters_mediaControlChannel) {
393 /* RTCP */
394 ret = expect_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
395 &channel->mediaControlChannel);
396 if (ret < 0)
397 return -1;
398 }
399
400 return 0;
401 }
402
403 /****************************************************************************/
404 static int process_olc(struct sk_buff *skb, struct nf_conn *ct,
405 enum ip_conntrack_info ctinfo,
406 unsigned char **data, int dataoff,
407 OpenLogicalChannel *olc)
408 {
409 int ret;
410
411 pr_debug("nf_ct_h323: OpenLogicalChannel\n");
412
413 if (olc->forwardLogicalChannelParameters.multiplexParameters.choice ==
414 eOpenLogicalChannel_forwardLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters)
415 {
416 ret = process_h245_channel(skb, ct, ctinfo, data, dataoff,
417 &olc->
418 forwardLogicalChannelParameters.
419 multiplexParameters.
420 h2250LogicalChannelParameters);
421 if (ret < 0)
422 return -1;
423 }
424
425 if ((olc->options &
426 eOpenLogicalChannel_reverseLogicalChannelParameters) &&
427 (olc->reverseLogicalChannelParameters.options &
428 eOpenLogicalChannel_reverseLogicalChannelParameters_multiplexParameters)
429 && (olc->reverseLogicalChannelParameters.multiplexParameters.
430 choice ==
431 eOpenLogicalChannel_reverseLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters))
432 {
433 ret =
434 process_h245_channel(skb, ct, ctinfo, data, dataoff,
435 &olc->
436 reverseLogicalChannelParameters.
437 multiplexParameters.
438 h2250LogicalChannelParameters);
439 if (ret < 0)
440 return -1;
441 }
442
443 if ((olc->options & eOpenLogicalChannel_separateStack) &&
444 olc->forwardLogicalChannelParameters.dataType.choice ==
445 eDataType_data &&
446 olc->forwardLogicalChannelParameters.dataType.data.application.
447 choice == eDataApplicationCapability_application_t120 &&
448 olc->forwardLogicalChannelParameters.dataType.data.application.
449 t120.choice == eDataProtocolCapability_separateLANStack &&
450 olc->separateStack.networkAddress.choice ==
451 eNetworkAccessParameters_networkAddress_localAreaAddress) {
452 ret = expect_t120(skb, ct, ctinfo, data, dataoff,
453 &olc->separateStack.networkAddress.
454 localAreaAddress);
455 if (ret < 0)
456 return -1;
457 }
458
459 return 0;
460 }
461
462 /****************************************************************************/
463 static int process_olca(struct sk_buff *skb, struct nf_conn *ct,
464 enum ip_conntrack_info ctinfo,
465 unsigned char **data, int dataoff,
466 OpenLogicalChannelAck *olca)
467 {
468 H2250LogicalChannelAckParameters *ack;
469 int ret;
470
471 pr_debug("nf_ct_h323: OpenLogicalChannelAck\n");
472
473 if ((olca->options &
474 eOpenLogicalChannelAck_reverseLogicalChannelParameters) &&
475 (olca->reverseLogicalChannelParameters.options &
476 eOpenLogicalChannelAck_reverseLogicalChannelParameters_multiplexParameters)
477 && (olca->reverseLogicalChannelParameters.multiplexParameters.
478 choice ==
479 eOpenLogicalChannelAck_reverseLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters))
480 {
481 ret = process_h245_channel(skb, ct, ctinfo, data, dataoff,
482 &olca->
483 reverseLogicalChannelParameters.
484 multiplexParameters.
485 h2250LogicalChannelParameters);
486 if (ret < 0)
487 return -1;
488 }
489
490 if ((olca->options &
491 eOpenLogicalChannelAck_forwardMultiplexAckParameters) &&
492 (olca->forwardMultiplexAckParameters.choice ==
493 eOpenLogicalChannelAck_forwardMultiplexAckParameters_h2250LogicalChannelAckParameters))
494 {
495 ack = &olca->forwardMultiplexAckParameters.
496 h2250LogicalChannelAckParameters;
497 if (ack->options &
498 eH2250LogicalChannelAckParameters_mediaChannel) {
499 /* RTP */
500 ret = expect_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
501 &ack->mediaChannel);
502 if (ret < 0)
503 return -1;
504 }
505
506 if (ack->options &
507 eH2250LogicalChannelAckParameters_mediaControlChannel) {
508 /* RTCP */
509 ret = expect_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
510 &ack->mediaControlChannel);
511 if (ret < 0)
512 return -1;
513 }
514 }
515
516 if ((olca->options & eOpenLogicalChannelAck_separateStack) &&
517 olca->separateStack.networkAddress.choice ==
518 eNetworkAccessParameters_networkAddress_localAreaAddress) {
519 ret = expect_t120(skb, ct, ctinfo, data, dataoff,
520 &olca->separateStack.networkAddress.
521 localAreaAddress);
522 if (ret < 0)
523 return -1;
524 }
525
526 return 0;
527 }
528
529 /****************************************************************************/
530 static int process_h245(struct sk_buff *skb, struct nf_conn *ct,
531 enum ip_conntrack_info ctinfo,
532 unsigned char **data, int dataoff,
533 MultimediaSystemControlMessage *mscm)
534 {
535 switch (mscm->choice) {
536 case eMultimediaSystemControlMessage_request:
537 if (mscm->request.choice ==
538 eRequestMessage_openLogicalChannel) {
539 return process_olc(skb, ct, ctinfo, data, dataoff,
540 &mscm->request.openLogicalChannel);
541 }
542 pr_debug("nf_ct_h323: H.245 Request %d\n",
543 mscm->request.choice);
544 break;
545 case eMultimediaSystemControlMessage_response:
546 if (mscm->response.choice ==
547 eResponseMessage_openLogicalChannelAck) {
548 return process_olca(skb, ct, ctinfo, data, dataoff,
549 &mscm->response.
550 openLogicalChannelAck);
551 }
552 pr_debug("nf_ct_h323: H.245 Response %d\n",
553 mscm->response.choice);
554 break;
555 default:
556 pr_debug("nf_ct_h323: H.245 signal %d\n", mscm->choice);
557 break;
558 }
559
560 return 0;
561 }
562
563 /****************************************************************************/
564 static int h245_help(struct sk_buff *skb, unsigned int protoff,
565 struct nf_conn *ct, enum ip_conntrack_info ctinfo)
566 {
567 static MultimediaSystemControlMessage mscm;
568 unsigned char *data = NULL;
569 int datalen;
570 int dataoff;
571 int ret;
572
573 /* Until there's been traffic both ways, don't look in packets. */
574 if (ctinfo != IP_CT_ESTABLISHED &&
575 ctinfo != IP_CT_ESTABLISHED + IP_CT_IS_REPLY) {
576 return NF_ACCEPT;
577 }
578 pr_debug("nf_ct_h245: skblen = %u\n", skb->len);
579
580 spin_lock_bh(&nf_h323_lock);
581
582 /* Process each TPKT */
583 while (get_tpkt_data(skb, protoff, ct, ctinfo,
584 &data, &datalen, &dataoff)) {
585 pr_debug("nf_ct_h245: TPKT len=%d ", datalen);
586 nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
587
588 /* Decode H.245 signal */
589 ret = DecodeMultimediaSystemControlMessage(data, datalen,
590 &mscm);
591 if (ret < 0) {
592 pr_debug("nf_ct_h245: decoding error: %s\n",
593 ret == H323_ERROR_BOUND ?
594 "out of bound" : "out of range");
595 /* We don't drop when decoding error */
596 break;
597 }
598
599 /* Process H.245 signal */
600 if (process_h245(skb, ct, ctinfo, &data, dataoff, &mscm) < 0)
601 goto drop;
602 }
603
604 spin_unlock_bh(&nf_h323_lock);
605 return NF_ACCEPT;
606
607 drop:
608 spin_unlock_bh(&nf_h323_lock);
609 if (net_ratelimit())
610 pr_info("nf_ct_h245: packet dropped\n");
611 return NF_DROP;
612 }
613
614 /****************************************************************************/
615 static const struct nf_conntrack_expect_policy h245_exp_policy = {
616 .max_expected = H323_RTP_CHANNEL_MAX * 4 + 2 /* T.120 */,
617 .timeout = 240,
618 };
619
620 static struct nf_conntrack_helper nf_conntrack_helper_h245 __read_mostly = {
621 .name = "H.245",
622 .me = THIS_MODULE,
623 .tuple.src.l3num = AF_UNSPEC,
624 .tuple.dst.protonum = IPPROTO_UDP,
625 .help = h245_help,
626 .expect_policy = &h245_exp_policy,
627 };
628
629 /****************************************************************************/
630 int get_h225_addr(struct nf_conn *ct, unsigned char *data,
631 TransportAddress *taddr,
632 union nf_inet_addr *addr, __be16 *port)
633 {
634 const unsigned char *p;
635 int len;
636
637 switch (taddr->choice) {
638 case eTransportAddress_ipAddress:
639 if (nf_ct_l3num(ct) != AF_INET)
640 return 0;
641 p = data + taddr->ipAddress.ip;
642 len = 4;
643 break;
644 case eTransportAddress_ip6Address:
645 if (nf_ct_l3num(ct) != AF_INET6)
646 return 0;
647 p = data + taddr->ip6Address.ip;
648 len = 16;
649 break;
650 default:
651 return 0;
652 }
653
654 memcpy(addr, p, len);
655 memset((void *)addr + len, 0, sizeof(*addr) - len);
656 memcpy(port, p + len, sizeof(__be16));
657
658 return 1;
659 }
660
661 /****************************************************************************/
662 static int expect_h245(struct sk_buff *skb, struct nf_conn *ct,
663 enum ip_conntrack_info ctinfo,
664 unsigned char **data, int dataoff,
665 TransportAddress *taddr)
666 {
667 int dir = CTINFO2DIR(ctinfo);
668 int ret = 0;
669 __be16 port;
670 union nf_inet_addr addr;
671 struct nf_conntrack_expect *exp;
672 typeof(nat_h245_hook) nat_h245;
673
674 /* Read h245Address */
675 if (!get_h225_addr(ct, *data, taddr, &addr, &port) ||
676 memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
677 port == 0)
678 return 0;
679
680 /* Create expect for h245 connection */
681 if ((exp = nf_ct_expect_alloc(ct)) == NULL)
682 return -1;
683 nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
684 &ct->tuplehash[!dir].tuple.src.u3,
685 &ct->tuplehash[!dir].tuple.dst.u3,
686 IPPROTO_TCP, NULL, &port);
687 exp->helper = &nf_conntrack_helper_h245;
688
689 if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
690 &ct->tuplehash[!dir].tuple.dst.u3,
691 sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
692 (nat_h245 = rcu_dereference(nat_h245_hook)) &&
693 ct->status & IPS_NAT_MASK) {
694 /* NAT needed */
695 ret = nat_h245(skb, ct, ctinfo, data, dataoff, taddr,
696 port, exp);
697 } else { /* Conntrack only */
698 if (nf_ct_expect_related(exp) == 0) {
699 pr_debug("nf_ct_q931: expect H.245 ");
700 nf_ct_dump_tuple(&exp->tuple);
701 } else
702 ret = -1;
703 }
704
705 nf_ct_expect_put(exp);
706
707 return ret;
708 }
709
710 /* If the calling party is on the same side of the forward-to party,
711 * we don't need to track the second call */
712 static int callforward_do_filter(const union nf_inet_addr *src,
713 const union nf_inet_addr *dst,
714 u_int8_t family)
715 {
716 const struct nf_afinfo *afinfo;
717 int ret = 0;
718
719 /* rcu_read_lock()ed by nf_hook_slow() */
720 afinfo = nf_get_afinfo(family);
721 if (!afinfo)
722 return 0;
723
724 switch (family) {
725 case AF_INET: {
726 struct flowi4 fl1, fl2;
727 struct rtable *rt1, *rt2;
728
729 memset(&fl1, 0, sizeof(fl1));
730 fl1.daddr = src->ip;
731
732 memset(&fl2, 0, sizeof(fl2));
733 fl2.daddr = dst->ip;
734 if (!afinfo->route(&init_net, (struct dst_entry **)&rt1,
735 flowi4_to_flowi(&fl1), false)) {
736 if (!afinfo->route(&init_net, (struct dst_entry **)&rt2,
737 flowi4_to_flowi(&fl2), false)) {
738 if (rt1->rt_gateway == rt2->rt_gateway &&
739 rt1->dst.dev == rt2->dst.dev)
740 ret = 1;
741 dst_release(&rt2->dst);
742 }
743 dst_release(&rt1->dst);
744 }
745 break;
746 }
747 #if defined(CONFIG_NF_CONNTRACK_IPV6) || \
748 defined(CONFIG_NF_CONNTRACK_IPV6_MODULE)
749 case AF_INET6: {
750 struct flowi6 fl1, fl2;
751 struct rt6_info *rt1, *rt2;
752
753 memset(&fl1, 0, sizeof(fl1));
754 ipv6_addr_copy(&fl1.daddr, &src->in6);
755
756 memset(&fl2, 0, sizeof(fl2));
757 ipv6_addr_copy(&fl2.daddr, &dst->in6);
758 if (!afinfo->route(&init_net, (struct dst_entry **)&rt1,
759 flowi6_to_flowi(&fl1), false)) {
760 if (!afinfo->route(&init_net, (struct dst_entry **)&rt2,
761 flowi6_to_flowi(&fl2), false)) {
762 if (!memcmp(&rt1->rt6i_gateway, &rt2->rt6i_gateway,
763 sizeof(rt1->rt6i_gateway)) &&
764 rt1->dst.dev == rt2->dst.dev)
765 ret = 1;
766 dst_release(&rt2->dst);
767 }
768 dst_release(&rt1->dst);
769 }
770 break;
771 }
772 #endif
773 }
774 return ret;
775
776 }
777
778 /****************************************************************************/
779 static int expect_callforwarding(struct sk_buff *skb,
780 struct nf_conn *ct,
781 enum ip_conntrack_info ctinfo,
782 unsigned char **data, int dataoff,
783 TransportAddress *taddr)
784 {
785 int dir = CTINFO2DIR(ctinfo);
786 int ret = 0;
787 __be16 port;
788 union nf_inet_addr addr;
789 struct nf_conntrack_expect *exp;
790 typeof(nat_callforwarding_hook) nat_callforwarding;
791
792 /* Read alternativeAddress */
793 if (!get_h225_addr(ct, *data, taddr, &addr, &port) || port == 0)
794 return 0;
795
796 /* If the calling party is on the same side of the forward-to party,
797 * we don't need to track the second call */
798 if (callforward_filter &&
799 callforward_do_filter(&addr, &ct->tuplehash[!dir].tuple.src.u3,
800 nf_ct_l3num(ct))) {
801 pr_debug("nf_ct_q931: Call Forwarding not tracked\n");
802 return 0;
803 }
804
805 /* Create expect for the second call leg */
806 if ((exp = nf_ct_expect_alloc(ct)) == NULL)
807 return -1;
808 nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
809 &ct->tuplehash[!dir].tuple.src.u3, &addr,
810 IPPROTO_TCP, NULL, &port);
811 exp->helper = nf_conntrack_helper_q931;
812
813 if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
814 &ct->tuplehash[!dir].tuple.dst.u3,
815 sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
816 (nat_callforwarding = rcu_dereference(nat_callforwarding_hook)) &&
817 ct->status & IPS_NAT_MASK) {
818 /* Need NAT */
819 ret = nat_callforwarding(skb, ct, ctinfo, data, dataoff,
820 taddr, port, exp);
821 } else { /* Conntrack only */
822 if (nf_ct_expect_related(exp) == 0) {
823 pr_debug("nf_ct_q931: expect Call Forwarding ");
824 nf_ct_dump_tuple(&exp->tuple);
825 } else
826 ret = -1;
827 }
828
829 nf_ct_expect_put(exp);
830
831 return ret;
832 }
833
834 /****************************************************************************/
835 static int process_setup(struct sk_buff *skb, struct nf_conn *ct,
836 enum ip_conntrack_info ctinfo,
837 unsigned char **data, int dataoff,
838 Setup_UUIE *setup)
839 {
840 int dir = CTINFO2DIR(ctinfo);
841 int ret;
842 int i;
843 __be16 port;
844 union nf_inet_addr addr;
845 typeof(set_h225_addr_hook) set_h225_addr;
846
847 pr_debug("nf_ct_q931: Setup\n");
848
849 if (setup->options & eSetup_UUIE_h245Address) {
850 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
851 &setup->h245Address);
852 if (ret < 0)
853 return -1;
854 }
855
856 set_h225_addr = rcu_dereference(set_h225_addr_hook);
857 if ((setup->options & eSetup_UUIE_destCallSignalAddress) &&
858 (set_h225_addr) && ct->status & IPS_NAT_MASK &&
859 get_h225_addr(ct, *data, &setup->destCallSignalAddress,
860 &addr, &port) &&
861 memcmp(&addr, &ct->tuplehash[!dir].tuple.src.u3, sizeof(addr))) {
862 pr_debug("nf_ct_q931: set destCallSignalAddress %pI6:%hu->%pI6:%hu\n",
863 &addr, ntohs(port), &ct->tuplehash[!dir].tuple.src.u3,
864 ntohs(ct->tuplehash[!dir].tuple.src.u.tcp.port));
865 ret = set_h225_addr(skb, data, dataoff,
866 &setup->destCallSignalAddress,
867 &ct->tuplehash[!dir].tuple.src.u3,
868 ct->tuplehash[!dir].tuple.src.u.tcp.port);
869 if (ret < 0)
870 return -1;
871 }
872
873 if ((setup->options & eSetup_UUIE_sourceCallSignalAddress) &&
874 (set_h225_addr) && ct->status & IPS_NAT_MASK &&
875 get_h225_addr(ct, *data, &setup->sourceCallSignalAddress,
876 &addr, &port) &&
877 memcmp(&addr, &ct->tuplehash[!dir].tuple.dst.u3, sizeof(addr))) {
878 pr_debug("nf_ct_q931: set sourceCallSignalAddress %pI6:%hu->%pI6:%hu\n",
879 &addr, ntohs(port), &ct->tuplehash[!dir].tuple.dst.u3,
880 ntohs(ct->tuplehash[!dir].tuple.dst.u.tcp.port));
881 ret = set_h225_addr(skb, data, dataoff,
882 &setup->sourceCallSignalAddress,
883 &ct->tuplehash[!dir].tuple.dst.u3,
884 ct->tuplehash[!dir].tuple.dst.u.tcp.port);
885 if (ret < 0)
886 return -1;
887 }
888
889 if (setup->options & eSetup_UUIE_fastStart) {
890 for (i = 0; i < setup->fastStart.count; i++) {
891 ret = process_olc(skb, ct, ctinfo, data, dataoff,
892 &setup->fastStart.item[i]);
893 if (ret < 0)
894 return -1;
895 }
896 }
897
898 return 0;
899 }
900
901 /****************************************************************************/
902 static int process_callproceeding(struct sk_buff *skb,
903 struct nf_conn *ct,
904 enum ip_conntrack_info ctinfo,
905 unsigned char **data, int dataoff,
906 CallProceeding_UUIE *callproc)
907 {
908 int ret;
909 int i;
910
911 pr_debug("nf_ct_q931: CallProceeding\n");
912
913 if (callproc->options & eCallProceeding_UUIE_h245Address) {
914 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
915 &callproc->h245Address);
916 if (ret < 0)
917 return -1;
918 }
919
920 if (callproc->options & eCallProceeding_UUIE_fastStart) {
921 for (i = 0; i < callproc->fastStart.count; i++) {
922 ret = process_olc(skb, ct, ctinfo, data, dataoff,
923 &callproc->fastStart.item[i]);
924 if (ret < 0)
925 return -1;
926 }
927 }
928
929 return 0;
930 }
931
932 /****************************************************************************/
933 static int process_connect(struct sk_buff *skb, struct nf_conn *ct,
934 enum ip_conntrack_info ctinfo,
935 unsigned char **data, int dataoff,
936 Connect_UUIE *connect)
937 {
938 int ret;
939 int i;
940
941 pr_debug("nf_ct_q931: Connect\n");
942
943 if (connect->options & eConnect_UUIE_h245Address) {
944 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
945 &connect->h245Address);
946 if (ret < 0)
947 return -1;
948 }
949
950 if (connect->options & eConnect_UUIE_fastStart) {
951 for (i = 0; i < connect->fastStart.count; i++) {
952 ret = process_olc(skb, ct, ctinfo, data, dataoff,
953 &connect->fastStart.item[i]);
954 if (ret < 0)
955 return -1;
956 }
957 }
958
959 return 0;
960 }
961
962 /****************************************************************************/
963 static int process_alerting(struct sk_buff *skb, struct nf_conn *ct,
964 enum ip_conntrack_info ctinfo,
965 unsigned char **data, int dataoff,
966 Alerting_UUIE *alert)
967 {
968 int ret;
969 int i;
970
971 pr_debug("nf_ct_q931: Alerting\n");
972
973 if (alert->options & eAlerting_UUIE_h245Address) {
974 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
975 &alert->h245Address);
976 if (ret < 0)
977 return -1;
978 }
979
980 if (alert->options & eAlerting_UUIE_fastStart) {
981 for (i = 0; i < alert->fastStart.count; i++) {
982 ret = process_olc(skb, ct, ctinfo, data, dataoff,
983 &alert->fastStart.item[i]);
984 if (ret < 0)
985 return -1;
986 }
987 }
988
989 return 0;
990 }
991
992 /****************************************************************************/
993 static int process_facility(struct sk_buff *skb, struct nf_conn *ct,
994 enum ip_conntrack_info ctinfo,
995 unsigned char **data, int dataoff,
996 Facility_UUIE *facility)
997 {
998 int ret;
999 int i;
1000
1001 pr_debug("nf_ct_q931: Facility\n");
1002
1003 if (facility->reason.choice == eFacilityReason_callForwarded) {
1004 if (facility->options & eFacility_UUIE_alternativeAddress)
1005 return expect_callforwarding(skb, ct, ctinfo, data,
1006 dataoff,
1007 &facility->
1008 alternativeAddress);
1009 return 0;
1010 }
1011
1012 if (facility->options & eFacility_UUIE_h245Address) {
1013 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
1014 &facility->h245Address);
1015 if (ret < 0)
1016 return -1;
1017 }
1018
1019 if (facility->options & eFacility_UUIE_fastStart) {
1020 for (i = 0; i < facility->fastStart.count; i++) {
1021 ret = process_olc(skb, ct, ctinfo, data, dataoff,
1022 &facility->fastStart.item[i]);
1023 if (ret < 0)
1024 return -1;
1025 }
1026 }
1027
1028 return 0;
1029 }
1030
1031 /****************************************************************************/
1032 static int process_progress(struct sk_buff *skb, struct nf_conn *ct,
1033 enum ip_conntrack_info ctinfo,
1034 unsigned char **data, int dataoff,
1035 Progress_UUIE *progress)
1036 {
1037 int ret;
1038 int i;
1039
1040 pr_debug("nf_ct_q931: Progress\n");
1041
1042 if (progress->options & eProgress_UUIE_h245Address) {
1043 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
1044 &progress->h245Address);
1045 if (ret < 0)
1046 return -1;
1047 }
1048
1049 if (progress->options & eProgress_UUIE_fastStart) {
1050 for (i = 0; i < progress->fastStart.count; i++) {
1051 ret = process_olc(skb, ct, ctinfo, data, dataoff,
1052 &progress->fastStart.item[i]);
1053 if (ret < 0)
1054 return -1;
1055 }
1056 }
1057
1058 return 0;
1059 }
1060
1061 /****************************************************************************/
1062 static int process_q931(struct sk_buff *skb, struct nf_conn *ct,
1063 enum ip_conntrack_info ctinfo,
1064 unsigned char **data, int dataoff, Q931 *q931)
1065 {
1066 H323_UU_PDU *pdu = &q931->UUIE.h323_uu_pdu;
1067 int i;
1068 int ret = 0;
1069
1070 switch (pdu->h323_message_body.choice) {
1071 case eH323_UU_PDU_h323_message_body_setup:
1072 ret = process_setup(skb, ct, ctinfo, data, dataoff,
1073 &pdu->h323_message_body.setup);
1074 break;
1075 case eH323_UU_PDU_h323_message_body_callProceeding:
1076 ret = process_callproceeding(skb, ct, ctinfo, data, dataoff,
1077 &pdu->h323_message_body.
1078 callProceeding);
1079 break;
1080 case eH323_UU_PDU_h323_message_body_connect:
1081 ret = process_connect(skb, ct, ctinfo, data, dataoff,
1082 &pdu->h323_message_body.connect);
1083 break;
1084 case eH323_UU_PDU_h323_message_body_alerting:
1085 ret = process_alerting(skb, ct, ctinfo, data, dataoff,
1086 &pdu->h323_message_body.alerting);
1087 break;
1088 case eH323_UU_PDU_h323_message_body_facility:
1089 ret = process_facility(skb, ct, ctinfo, data, dataoff,
1090 &pdu->h323_message_body.facility);
1091 break;
1092 case eH323_UU_PDU_h323_message_body_progress:
1093 ret = process_progress(skb, ct, ctinfo, data, dataoff,
1094 &pdu->h323_message_body.progress);
1095 break;
1096 default:
1097 pr_debug("nf_ct_q931: Q.931 signal %d\n",
1098 pdu->h323_message_body.choice);
1099 break;
1100 }
1101
1102 if (ret < 0)
1103 return -1;
1104
1105 if (pdu->options & eH323_UU_PDU_h245Control) {
1106 for (i = 0; i < pdu->h245Control.count; i++) {
1107 ret = process_h245(skb, ct, ctinfo, data, dataoff,
1108 &pdu->h245Control.item[i]);
1109 if (ret < 0)
1110 return -1;
1111 }
1112 }
1113
1114 return 0;
1115 }
1116
1117 /****************************************************************************/
1118 static int q931_help(struct sk_buff *skb, unsigned int protoff,
1119 struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1120 {
1121 static Q931 q931;
1122 unsigned char *data = NULL;
1123 int datalen;
1124 int dataoff;
1125 int ret;
1126
1127 /* Until there's been traffic both ways, don't look in packets. */
1128 if (ctinfo != IP_CT_ESTABLISHED &&
1129 ctinfo != IP_CT_ESTABLISHED + IP_CT_IS_REPLY) {
1130 return NF_ACCEPT;
1131 }
1132 pr_debug("nf_ct_q931: skblen = %u\n", skb->len);
1133
1134 spin_lock_bh(&nf_h323_lock);
1135
1136 /* Process each TPKT */
1137 while (get_tpkt_data(skb, protoff, ct, ctinfo,
1138 &data, &datalen, &dataoff)) {
1139 pr_debug("nf_ct_q931: TPKT len=%d ", datalen);
1140 nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1141
1142 /* Decode Q.931 signal */
1143 ret = DecodeQ931(data, datalen, &q931);
1144 if (ret < 0) {
1145 pr_debug("nf_ct_q931: decoding error: %s\n",
1146 ret == H323_ERROR_BOUND ?
1147 "out of bound" : "out of range");
1148 /* We don't drop when decoding error */
1149 break;
1150 }
1151
1152 /* Process Q.931 signal */
1153 if (process_q931(skb, ct, ctinfo, &data, dataoff, &q931) < 0)
1154 goto drop;
1155 }
1156
1157 spin_unlock_bh(&nf_h323_lock);
1158 return NF_ACCEPT;
1159
1160 drop:
1161 spin_unlock_bh(&nf_h323_lock);
1162 if (net_ratelimit())
1163 pr_info("nf_ct_q931: packet dropped\n");
1164 return NF_DROP;
1165 }
1166
1167 /****************************************************************************/
1168 static const struct nf_conntrack_expect_policy q931_exp_policy = {
1169 /* T.120 and H.245 */
1170 .max_expected = H323_RTP_CHANNEL_MAX * 4 + 4,
1171 .timeout = 240,
1172 };
1173
1174 static struct nf_conntrack_helper nf_conntrack_helper_q931[] __read_mostly = {
1175 {
1176 .name = "Q.931",
1177 .me = THIS_MODULE,
1178 .tuple.src.l3num = AF_INET,
1179 .tuple.src.u.tcp.port = cpu_to_be16(Q931_PORT),
1180 .tuple.dst.protonum = IPPROTO_TCP,
1181 .help = q931_help,
1182 .expect_policy = &q931_exp_policy,
1183 },
1184 {
1185 .name = "Q.931",
1186 .me = THIS_MODULE,
1187 .tuple.src.l3num = AF_INET6,
1188 .tuple.src.u.tcp.port = cpu_to_be16(Q931_PORT),
1189 .tuple.dst.protonum = IPPROTO_TCP,
1190 .help = q931_help,
1191 .expect_policy = &q931_exp_policy,
1192 },
1193 };
1194
1195 /****************************************************************************/
1196 static unsigned char *get_udp_data(struct sk_buff *skb, unsigned int protoff,
1197 int *datalen)
1198 {
1199 const struct udphdr *uh;
1200 struct udphdr _uh;
1201 int dataoff;
1202
1203 uh = skb_header_pointer(skb, protoff, sizeof(_uh), &_uh);
1204 if (uh == NULL)
1205 return NULL;
1206 dataoff = protoff + sizeof(_uh);
1207 if (dataoff >= skb->len)
1208 return NULL;
1209 *datalen = skb->len - dataoff;
1210 return skb_header_pointer(skb, dataoff, *datalen, h323_buffer);
1211 }
1212
1213 /****************************************************************************/
1214 static struct nf_conntrack_expect *find_expect(struct nf_conn *ct,
1215 union nf_inet_addr *addr,
1216 __be16 port)
1217 {
1218 struct net *net = nf_ct_net(ct);
1219 struct nf_conntrack_expect *exp;
1220 struct nf_conntrack_tuple tuple;
1221
1222 memset(&tuple.src.u3, 0, sizeof(tuple.src.u3));
1223 tuple.src.u.tcp.port = 0;
1224 memcpy(&tuple.dst.u3, addr, sizeof(tuple.dst.u3));
1225 tuple.dst.u.tcp.port = port;
1226 tuple.dst.protonum = IPPROTO_TCP;
1227
1228 exp = __nf_ct_expect_find(net, nf_ct_zone(ct), &tuple);
1229 if (exp && exp->master == ct)
1230 return exp;
1231 return NULL;
1232 }
1233
1234 /****************************************************************************/
1235 static int set_expect_timeout(struct nf_conntrack_expect *exp,
1236 unsigned timeout)
1237 {
1238 if (!exp || !del_timer(&exp->timeout))
1239 return 0;
1240
1241 exp->timeout.expires = jiffies + timeout * HZ;
1242 add_timer(&exp->timeout);
1243
1244 return 1;
1245 }
1246
1247 /****************************************************************************/
1248 static int expect_q931(struct sk_buff *skb, struct nf_conn *ct,
1249 enum ip_conntrack_info ctinfo,
1250 unsigned char **data,
1251 TransportAddress *taddr, int count)
1252 {
1253 struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1254 int dir = CTINFO2DIR(ctinfo);
1255 int ret = 0;
1256 int i;
1257 __be16 port;
1258 union nf_inet_addr addr;
1259 struct nf_conntrack_expect *exp;
1260 typeof(nat_q931_hook) nat_q931;
1261
1262 /* Look for the first related address */
1263 for (i = 0; i < count; i++) {
1264 if (get_h225_addr(ct, *data, &taddr[i], &addr, &port) &&
1265 memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3,
1266 sizeof(addr)) == 0 && port != 0)
1267 break;
1268 }
1269
1270 if (i >= count) /* Not found */
1271 return 0;
1272
1273 /* Create expect for Q.931 */
1274 if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1275 return -1;
1276 nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1277 gkrouted_only ? /* only accept calls from GK? */
1278 &ct->tuplehash[!dir].tuple.src.u3 : NULL,
1279 &ct->tuplehash[!dir].tuple.dst.u3,
1280 IPPROTO_TCP, NULL, &port);
1281 exp->helper = nf_conntrack_helper_q931;
1282 exp->flags = NF_CT_EXPECT_PERMANENT; /* Accept multiple calls */
1283
1284 nat_q931 = rcu_dereference(nat_q931_hook);
1285 if (nat_q931 && ct->status & IPS_NAT_MASK) { /* Need NAT */
1286 ret = nat_q931(skb, ct, ctinfo, data, taddr, i, port, exp);
1287 } else { /* Conntrack only */
1288 if (nf_ct_expect_related(exp) == 0) {
1289 pr_debug("nf_ct_ras: expect Q.931 ");
1290 nf_ct_dump_tuple(&exp->tuple);
1291
1292 /* Save port for looking up expect in processing RCF */
1293 info->sig_port[dir] = port;
1294 } else
1295 ret = -1;
1296 }
1297
1298 nf_ct_expect_put(exp);
1299
1300 return ret;
1301 }
1302
1303 /****************************************************************************/
1304 static int process_grq(struct sk_buff *skb, struct nf_conn *ct,
1305 enum ip_conntrack_info ctinfo,
1306 unsigned char **data, GatekeeperRequest *grq)
1307 {
1308 typeof(set_ras_addr_hook) set_ras_addr;
1309
1310 pr_debug("nf_ct_ras: GRQ\n");
1311
1312 set_ras_addr = rcu_dereference(set_ras_addr_hook);
1313 if (set_ras_addr && ct->status & IPS_NAT_MASK) /* NATed */
1314 return set_ras_addr(skb, ct, ctinfo, data,
1315 &grq->rasAddress, 1);
1316 return 0;
1317 }
1318
1319 /****************************************************************************/
1320 static int process_gcf(struct sk_buff *skb, struct nf_conn *ct,
1321 enum ip_conntrack_info ctinfo,
1322 unsigned char **data, GatekeeperConfirm *gcf)
1323 {
1324 int dir = CTINFO2DIR(ctinfo);
1325 int ret = 0;
1326 __be16 port;
1327 union nf_inet_addr addr;
1328 struct nf_conntrack_expect *exp;
1329
1330 pr_debug("nf_ct_ras: GCF\n");
1331
1332 if (!get_h225_addr(ct, *data, &gcf->rasAddress, &addr, &port))
1333 return 0;
1334
1335 /* Registration port is the same as discovery port */
1336 if (!memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1337 port == ct->tuplehash[dir].tuple.src.u.udp.port)
1338 return 0;
1339
1340 /* Avoid RAS expectation loops. A GCF is never expected. */
1341 if (test_bit(IPS_EXPECTED_BIT, &ct->status))
1342 return 0;
1343
1344 /* Need new expect */
1345 if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1346 return -1;
1347 nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1348 &ct->tuplehash[!dir].tuple.src.u3, &addr,
1349 IPPROTO_UDP, NULL, &port);
1350 exp->helper = nf_conntrack_helper_ras;
1351
1352 if (nf_ct_expect_related(exp) == 0) {
1353 pr_debug("nf_ct_ras: expect RAS ");
1354 nf_ct_dump_tuple(&exp->tuple);
1355 } else
1356 ret = -1;
1357
1358 nf_ct_expect_put(exp);
1359
1360 return ret;
1361 }
1362
1363 /****************************************************************************/
1364 static int process_rrq(struct sk_buff *skb, struct nf_conn *ct,
1365 enum ip_conntrack_info ctinfo,
1366 unsigned char **data, RegistrationRequest *rrq)
1367 {
1368 struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1369 int ret;
1370 typeof(set_ras_addr_hook) set_ras_addr;
1371
1372 pr_debug("nf_ct_ras: RRQ\n");
1373
1374 ret = expect_q931(skb, ct, ctinfo, data,
1375 rrq->callSignalAddress.item,
1376 rrq->callSignalAddress.count);
1377 if (ret < 0)
1378 return -1;
1379
1380 set_ras_addr = rcu_dereference(set_ras_addr_hook);
1381 if (set_ras_addr && ct->status & IPS_NAT_MASK) {
1382 ret = set_ras_addr(skb, ct, ctinfo, data,
1383 rrq->rasAddress.item,
1384 rrq->rasAddress.count);
1385 if (ret < 0)
1386 return -1;
1387 }
1388
1389 if (rrq->options & eRegistrationRequest_timeToLive) {
1390 pr_debug("nf_ct_ras: RRQ TTL = %u seconds\n", rrq->timeToLive);
1391 info->timeout = rrq->timeToLive;
1392 } else
1393 info->timeout = default_rrq_ttl;
1394
1395 return 0;
1396 }
1397
1398 /****************************************************************************/
1399 static int process_rcf(struct sk_buff *skb, struct nf_conn *ct,
1400 enum ip_conntrack_info ctinfo,
1401 unsigned char **data, RegistrationConfirm *rcf)
1402 {
1403 struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1404 int dir = CTINFO2DIR(ctinfo);
1405 int ret;
1406 struct nf_conntrack_expect *exp;
1407 typeof(set_sig_addr_hook) set_sig_addr;
1408
1409 pr_debug("nf_ct_ras: RCF\n");
1410
1411 set_sig_addr = rcu_dereference(set_sig_addr_hook);
1412 if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1413 ret = set_sig_addr(skb, ct, ctinfo, data,
1414 rcf->callSignalAddress.item,
1415 rcf->callSignalAddress.count);
1416 if (ret < 0)
1417 return -1;
1418 }
1419
1420 if (rcf->options & eRegistrationConfirm_timeToLive) {
1421 pr_debug("nf_ct_ras: RCF TTL = %u seconds\n", rcf->timeToLive);
1422 info->timeout = rcf->timeToLive;
1423 }
1424
1425 if (info->timeout > 0) {
1426 pr_debug("nf_ct_ras: set RAS connection timeout to "
1427 "%u seconds\n", info->timeout);
1428 nf_ct_refresh(ct, skb, info->timeout * HZ);
1429
1430 /* Set expect timeout */
1431 spin_lock_bh(&nf_conntrack_lock);
1432 exp = find_expect(ct, &ct->tuplehash[dir].tuple.dst.u3,
1433 info->sig_port[!dir]);
1434 if (exp) {
1435 pr_debug("nf_ct_ras: set Q.931 expect "
1436 "timeout to %u seconds for",
1437 info->timeout);
1438 nf_ct_dump_tuple(&exp->tuple);
1439 set_expect_timeout(exp, info->timeout);
1440 }
1441 spin_unlock_bh(&nf_conntrack_lock);
1442 }
1443
1444 return 0;
1445 }
1446
1447 /****************************************************************************/
1448 static int process_urq(struct sk_buff *skb, struct nf_conn *ct,
1449 enum ip_conntrack_info ctinfo,
1450 unsigned char **data, UnregistrationRequest *urq)
1451 {
1452 struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1453 int dir = CTINFO2DIR(ctinfo);
1454 int ret;
1455 typeof(set_sig_addr_hook) set_sig_addr;
1456
1457 pr_debug("nf_ct_ras: URQ\n");
1458
1459 set_sig_addr = rcu_dereference(set_sig_addr_hook);
1460 if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1461 ret = set_sig_addr(skb, ct, ctinfo, data,
1462 urq->callSignalAddress.item,
1463 urq->callSignalAddress.count);
1464 if (ret < 0)
1465 return -1;
1466 }
1467
1468 /* Clear old expect */
1469 nf_ct_remove_expectations(ct);
1470 info->sig_port[dir] = 0;
1471 info->sig_port[!dir] = 0;
1472
1473 /* Give it 30 seconds for UCF or URJ */
1474 nf_ct_refresh(ct, skb, 30 * HZ);
1475
1476 return 0;
1477 }
1478
1479 /****************************************************************************/
1480 static int process_arq(struct sk_buff *skb, struct nf_conn *ct,
1481 enum ip_conntrack_info ctinfo,
1482 unsigned char **data, AdmissionRequest *arq)
1483 {
1484 const struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1485 int dir = CTINFO2DIR(ctinfo);
1486 __be16 port;
1487 union nf_inet_addr addr;
1488 typeof(set_h225_addr_hook) set_h225_addr;
1489
1490 pr_debug("nf_ct_ras: ARQ\n");
1491
1492 set_h225_addr = rcu_dereference(set_h225_addr_hook);
1493 if ((arq->options & eAdmissionRequest_destCallSignalAddress) &&
1494 get_h225_addr(ct, *data, &arq->destCallSignalAddress,
1495 &addr, &port) &&
1496 !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1497 port == info->sig_port[dir] &&
1498 set_h225_addr && ct->status & IPS_NAT_MASK) {
1499 /* Answering ARQ */
1500 return set_h225_addr(skb, data, 0,
1501 &arq->destCallSignalAddress,
1502 &ct->tuplehash[!dir].tuple.dst.u3,
1503 info->sig_port[!dir]);
1504 }
1505
1506 if ((arq->options & eAdmissionRequest_srcCallSignalAddress) &&
1507 get_h225_addr(ct, *data, &arq->srcCallSignalAddress,
1508 &addr, &port) &&
1509 !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1510 set_h225_addr && ct->status & IPS_NAT_MASK) {
1511 /* Calling ARQ */
1512 return set_h225_addr(skb, data, 0,
1513 &arq->srcCallSignalAddress,
1514 &ct->tuplehash[!dir].tuple.dst.u3,
1515 port);
1516 }
1517
1518 return 0;
1519 }
1520
1521 /****************************************************************************/
1522 static int process_acf(struct sk_buff *skb, struct nf_conn *ct,
1523 enum ip_conntrack_info ctinfo,
1524 unsigned char **data, AdmissionConfirm *acf)
1525 {
1526 int dir = CTINFO2DIR(ctinfo);
1527 int ret = 0;
1528 __be16 port;
1529 union nf_inet_addr addr;
1530 struct nf_conntrack_expect *exp;
1531 typeof(set_sig_addr_hook) set_sig_addr;
1532
1533 pr_debug("nf_ct_ras: ACF\n");
1534
1535 if (!get_h225_addr(ct, *data, &acf->destCallSignalAddress,
1536 &addr, &port))
1537 return 0;
1538
1539 if (!memcmp(&addr, &ct->tuplehash[dir].tuple.dst.u3, sizeof(addr))) {
1540 /* Answering ACF */
1541 set_sig_addr = rcu_dereference(set_sig_addr_hook);
1542 if (set_sig_addr && ct->status & IPS_NAT_MASK)
1543 return set_sig_addr(skb, ct, ctinfo, data,
1544 &acf->destCallSignalAddress, 1);
1545 return 0;
1546 }
1547
1548 /* Need new expect */
1549 if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1550 return -1;
1551 nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1552 &ct->tuplehash[!dir].tuple.src.u3, &addr,
1553 IPPROTO_TCP, NULL, &port);
1554 exp->flags = NF_CT_EXPECT_PERMANENT;
1555 exp->helper = nf_conntrack_helper_q931;
1556
1557 if (nf_ct_expect_related(exp) == 0) {
1558 pr_debug("nf_ct_ras: expect Q.931 ");
1559 nf_ct_dump_tuple(&exp->tuple);
1560 } else
1561 ret = -1;
1562
1563 nf_ct_expect_put(exp);
1564
1565 return ret;
1566 }
1567
1568 /****************************************************************************/
1569 static int process_lrq(struct sk_buff *skb, struct nf_conn *ct,
1570 enum ip_conntrack_info ctinfo,
1571 unsigned char **data, LocationRequest *lrq)
1572 {
1573 typeof(set_ras_addr_hook) set_ras_addr;
1574
1575 pr_debug("nf_ct_ras: LRQ\n");
1576
1577 set_ras_addr = rcu_dereference(set_ras_addr_hook);
1578 if (set_ras_addr && ct->status & IPS_NAT_MASK)
1579 return set_ras_addr(skb, ct, ctinfo, data,
1580 &lrq->replyAddress, 1);
1581 return 0;
1582 }
1583
1584 /****************************************************************************/
1585 static int process_lcf(struct sk_buff *skb, struct nf_conn *ct,
1586 enum ip_conntrack_info ctinfo,
1587 unsigned char **data, LocationConfirm *lcf)
1588 {
1589 int dir = CTINFO2DIR(ctinfo);
1590 int ret = 0;
1591 __be16 port;
1592 union nf_inet_addr addr;
1593 struct nf_conntrack_expect *exp;
1594
1595 pr_debug("nf_ct_ras: LCF\n");
1596
1597 if (!get_h225_addr(ct, *data, &lcf->callSignalAddress,
1598 &addr, &port))
1599 return 0;
1600
1601 /* Need new expect for call signal */
1602 if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1603 return -1;
1604 nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1605 &ct->tuplehash[!dir].tuple.src.u3, &addr,
1606 IPPROTO_TCP, NULL, &port);
1607 exp->flags = NF_CT_EXPECT_PERMANENT;
1608 exp->helper = nf_conntrack_helper_q931;
1609
1610 if (nf_ct_expect_related(exp) == 0) {
1611 pr_debug("nf_ct_ras: expect Q.931 ");
1612 nf_ct_dump_tuple(&exp->tuple);
1613 } else
1614 ret = -1;
1615
1616 nf_ct_expect_put(exp);
1617
1618 /* Ignore rasAddress */
1619
1620 return ret;
1621 }
1622
1623 /****************************************************************************/
1624 static int process_irr(struct sk_buff *skb, struct nf_conn *ct,
1625 enum ip_conntrack_info ctinfo,
1626 unsigned char **data, InfoRequestResponse *irr)
1627 {
1628 int ret;
1629 typeof(set_ras_addr_hook) set_ras_addr;
1630 typeof(set_sig_addr_hook) set_sig_addr;
1631
1632 pr_debug("nf_ct_ras: IRR\n");
1633
1634 set_ras_addr = rcu_dereference(set_ras_addr_hook);
1635 if (set_ras_addr && ct->status & IPS_NAT_MASK) {
1636 ret = set_ras_addr(skb, ct, ctinfo, data,
1637 &irr->rasAddress, 1);
1638 if (ret < 0)
1639 return -1;
1640 }
1641
1642 set_sig_addr = rcu_dereference(set_sig_addr_hook);
1643 if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1644 ret = set_sig_addr(skb, ct, ctinfo, data,
1645 irr->callSignalAddress.item,
1646 irr->callSignalAddress.count);
1647 if (ret < 0)
1648 return -1;
1649 }
1650
1651 return 0;
1652 }
1653
1654 /****************************************************************************/
1655 static int process_ras(struct sk_buff *skb, struct nf_conn *ct,
1656 enum ip_conntrack_info ctinfo,
1657 unsigned char **data, RasMessage *ras)
1658 {
1659 switch (ras->choice) {
1660 case eRasMessage_gatekeeperRequest:
1661 return process_grq(skb, ct, ctinfo, data,
1662 &ras->gatekeeperRequest);
1663 case eRasMessage_gatekeeperConfirm:
1664 return process_gcf(skb, ct, ctinfo, data,
1665 &ras->gatekeeperConfirm);
1666 case eRasMessage_registrationRequest:
1667 return process_rrq(skb, ct, ctinfo, data,
1668 &ras->registrationRequest);
1669 case eRasMessage_registrationConfirm:
1670 return process_rcf(skb, ct, ctinfo, data,
1671 &ras->registrationConfirm);
1672 case eRasMessage_unregistrationRequest:
1673 return process_urq(skb, ct, ctinfo, data,
1674 &ras->unregistrationRequest);
1675 case eRasMessage_admissionRequest:
1676 return process_arq(skb, ct, ctinfo, data,
1677 &ras->admissionRequest);
1678 case eRasMessage_admissionConfirm:
1679 return process_acf(skb, ct, ctinfo, data,
1680 &ras->admissionConfirm);
1681 case eRasMessage_locationRequest:
1682 return process_lrq(skb, ct, ctinfo, data,
1683 &ras->locationRequest);
1684 case eRasMessage_locationConfirm:
1685 return process_lcf(skb, ct, ctinfo, data,
1686 &ras->locationConfirm);
1687 case eRasMessage_infoRequestResponse:
1688 return process_irr(skb, ct, ctinfo, data,
1689 &ras->infoRequestResponse);
1690 default:
1691 pr_debug("nf_ct_ras: RAS message %d\n", ras->choice);
1692 break;
1693 }
1694
1695 return 0;
1696 }
1697
1698 /****************************************************************************/
1699 static int ras_help(struct sk_buff *skb, unsigned int protoff,
1700 struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1701 {
1702 static RasMessage ras;
1703 unsigned char *data;
1704 int datalen = 0;
1705 int ret;
1706
1707 pr_debug("nf_ct_ras: skblen = %u\n", skb->len);
1708
1709 spin_lock_bh(&nf_h323_lock);
1710
1711 /* Get UDP data */
1712 data = get_udp_data(skb, protoff, &datalen);
1713 if (data == NULL)
1714 goto accept;
1715 pr_debug("nf_ct_ras: RAS message len=%d ", datalen);
1716 nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1717
1718 /* Decode RAS message */
1719 ret = DecodeRasMessage(data, datalen, &ras);
1720 if (ret < 0) {
1721 pr_debug("nf_ct_ras: decoding error: %s\n",
1722 ret == H323_ERROR_BOUND ?
1723 "out of bound" : "out of range");
1724 goto accept;
1725 }
1726
1727 /* Process RAS message */
1728 if (process_ras(skb, ct, ctinfo, &data, &ras) < 0)
1729 goto drop;
1730
1731 accept:
1732 spin_unlock_bh(&nf_h323_lock);
1733 return NF_ACCEPT;
1734
1735 drop:
1736 spin_unlock_bh(&nf_h323_lock);
1737 if (net_ratelimit())
1738 pr_info("nf_ct_ras: packet dropped\n");
1739 return NF_DROP;
1740 }
1741
1742 /****************************************************************************/
1743 static const struct nf_conntrack_expect_policy ras_exp_policy = {
1744 .max_expected = 32,
1745 .timeout = 240,
1746 };
1747
1748 static struct nf_conntrack_helper nf_conntrack_helper_ras[] __read_mostly = {
1749 {
1750 .name = "RAS",
1751 .me = THIS_MODULE,
1752 .tuple.src.l3num = AF_INET,
1753 .tuple.src.u.udp.port = cpu_to_be16(RAS_PORT),
1754 .tuple.dst.protonum = IPPROTO_UDP,
1755 .help = ras_help,
1756 .expect_policy = &ras_exp_policy,
1757 },
1758 {
1759 .name = "RAS",
1760 .me = THIS_MODULE,
1761 .tuple.src.l3num = AF_INET6,
1762 .tuple.src.u.udp.port = cpu_to_be16(RAS_PORT),
1763 .tuple.dst.protonum = IPPROTO_UDP,
1764 .help = ras_help,
1765 .expect_policy = &ras_exp_policy,
1766 },
1767 };
1768
1769 /****************************************************************************/
1770 static void __exit nf_conntrack_h323_fini(void)
1771 {
1772 nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[1]);
1773 nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1774 nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1775 nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1776 nf_conntrack_helper_unregister(&nf_conntrack_helper_h245);
1777 kfree(h323_buffer);
1778 pr_debug("nf_ct_h323: fini\n");
1779 }
1780
1781 /****************************************************************************/
1782 static int __init nf_conntrack_h323_init(void)
1783 {
1784 int ret;
1785
1786 h323_buffer = kmalloc(65536, GFP_KERNEL);
1787 if (!h323_buffer)
1788 return -ENOMEM;
1789 ret = nf_conntrack_helper_register(&nf_conntrack_helper_h245);
1790 if (ret < 0)
1791 goto err1;
1792 ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[0]);
1793 if (ret < 0)
1794 goto err2;
1795 ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[1]);
1796 if (ret < 0)
1797 goto err3;
1798 ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[0]);
1799 if (ret < 0)
1800 goto err4;
1801 ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[1]);
1802 if (ret < 0)
1803 goto err5;
1804 pr_debug("nf_ct_h323: init success\n");
1805 return 0;
1806
1807 err5:
1808 nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1809 err4:
1810 nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1811 err3:
1812 nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1813 err2:
1814 nf_conntrack_helper_unregister(&nf_conntrack_helper_h245);
1815 err1:
1816 kfree(h323_buffer);
1817 return ret;
1818 }
1819
1820 /****************************************************************************/
1821 module_init(nf_conntrack_h323_init);
1822 module_exit(nf_conntrack_h323_fini);
1823
1824 EXPORT_SYMBOL_GPL(get_h225_addr);
1825 EXPORT_SYMBOL_GPL(set_h245_addr_hook);
1826 EXPORT_SYMBOL_GPL(set_h225_addr_hook);
1827 EXPORT_SYMBOL_GPL(set_sig_addr_hook);
1828 EXPORT_SYMBOL_GPL(set_ras_addr_hook);
1829 EXPORT_SYMBOL_GPL(nat_rtp_rtcp_hook);
1830 EXPORT_SYMBOL_GPL(nat_t120_hook);
1831 EXPORT_SYMBOL_GPL(nat_h245_hook);
1832 EXPORT_SYMBOL_GPL(nat_callforwarding_hook);
1833 EXPORT_SYMBOL_GPL(nat_q931_hook);
1834
1835 MODULE_AUTHOR("Jing Min Zhao <zhaojingmin@users.sourceforge.net>");
1836 MODULE_DESCRIPTION("H.323 connection tracking helper");
1837 MODULE_LICENSE("GPL");
1838 MODULE_ALIAS("ip_conntrack_h323");
1839 MODULE_ALIAS_NFCT_HELPER("h323");
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree