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drm: Fix authentication kernel crash
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / net / netfilter / nf_conntrack_h323_main.c
blobf03c2d4539f6b8517530c899b2bc2419e4f80f88
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 && ctinfo != IP_CT_ESTABLISHED_REPLY)
575 return NF_ACCEPT;
576
577 pr_debug("nf_ct_h245: skblen = %u\n", skb->len);
578
579 spin_lock_bh(&nf_h323_lock);
580
581 /* Process each TPKT */
582 while (get_tpkt_data(skb, protoff, ct, ctinfo,
583 &data, &datalen, &dataoff)) {
584 pr_debug("nf_ct_h245: TPKT len=%d ", datalen);
585 nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
586
587 /* Decode H.245 signal */
588 ret = DecodeMultimediaSystemControlMessage(data, datalen,
589 &mscm);
590 if (ret < 0) {
591 pr_debug("nf_ct_h245: decoding error: %s\n",
592 ret == H323_ERROR_BOUND ?
593 "out of bound" : "out of range");
594 /* We don't drop when decoding error */
595 break;
596 }
597
598 /* Process H.245 signal */
599 if (process_h245(skb, ct, ctinfo, &data, dataoff, &mscm) < 0)
600 goto drop;
601 }
602
603 spin_unlock_bh(&nf_h323_lock);
604 return NF_ACCEPT;
605
606 drop:
607 spin_unlock_bh(&nf_h323_lock);
608 if (net_ratelimit())
609 pr_info("nf_ct_h245: packet dropped\n");
610 return NF_DROP;
611 }
612
613 /****************************************************************************/
614 static const struct nf_conntrack_expect_policy h245_exp_policy = {
615 .max_expected = H323_RTP_CHANNEL_MAX * 4 + 2 /* T.120 */,
616 .timeout = 240,
617 };
618
619 static struct nf_conntrack_helper nf_conntrack_helper_h245 __read_mostly = {
620 .name = "H.245",
621 .me = THIS_MODULE,
622 .tuple.src.l3num = AF_UNSPEC,
623 .tuple.dst.protonum = IPPROTO_UDP,
624 .help = h245_help,
625 .expect_policy = &h245_exp_policy,
626 };
627
628 /****************************************************************************/
629 int get_h225_addr(struct nf_conn *ct, unsigned char *data,
630 TransportAddress *taddr,
631 union nf_inet_addr *addr, __be16 *port)
632 {
633 const unsigned char *p;
634 int len;
635
636 switch (taddr->choice) {
637 case eTransportAddress_ipAddress:
638 if (nf_ct_l3num(ct) != AF_INET)
639 return 0;
640 p = data + taddr->ipAddress.ip;
641 len = 4;
642 break;
643 case eTransportAddress_ip6Address:
644 if (nf_ct_l3num(ct) != AF_INET6)
645 return 0;
646 p = data + taddr->ip6Address.ip;
647 len = 16;
648 break;
649 default:
650 return 0;
651 }
652
653 memcpy(addr, p, len);
654 memset((void *)addr + len, 0, sizeof(*addr) - len);
655 memcpy(port, p + len, sizeof(__be16));
656
657 return 1;
658 }
659
660 /****************************************************************************/
661 static int expect_h245(struct sk_buff *skb, struct nf_conn *ct,
662 enum ip_conntrack_info ctinfo,
663 unsigned char **data, int dataoff,
664 TransportAddress *taddr)
665 {
666 int dir = CTINFO2DIR(ctinfo);
667 int ret = 0;
668 __be16 port;
669 union nf_inet_addr addr;
670 struct nf_conntrack_expect *exp;
671 typeof(nat_h245_hook) nat_h245;
672
673 /* Read h245Address */
674 if (!get_h225_addr(ct, *data, taddr, &addr, &port) ||
675 memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
676 port == 0)
677 return 0;
678
679 /* Create expect for h245 connection */
680 if ((exp = nf_ct_expect_alloc(ct)) == NULL)
681 return -1;
682 nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
683 &ct->tuplehash[!dir].tuple.src.u3,
684 &ct->tuplehash[!dir].tuple.dst.u3,
685 IPPROTO_TCP, NULL, &port);
686 exp->helper = &nf_conntrack_helper_h245;
687
688 if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
689 &ct->tuplehash[!dir].tuple.dst.u3,
690 sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
691 (nat_h245 = rcu_dereference(nat_h245_hook)) &&
692 ct->status & IPS_NAT_MASK) {
693 /* NAT needed */
694 ret = nat_h245(skb, ct, ctinfo, data, dataoff, taddr,
695 port, exp);
696 } else { /* Conntrack only */
697 if (nf_ct_expect_related(exp) == 0) {
698 pr_debug("nf_ct_q931: expect H.245 ");
699 nf_ct_dump_tuple(&exp->tuple);
700 } else
701 ret = -1;
702 }
703
704 nf_ct_expect_put(exp);
705
706 return ret;
707 }
708
709 /* If the calling party is on the same side of the forward-to party,
710 * we don't need to track the second call */
711 static int callforward_do_filter(const union nf_inet_addr *src,
712 const union nf_inet_addr *dst,
713 u_int8_t family)
714 {
715 const struct nf_afinfo *afinfo;
716 int ret = 0;
717
718 /* rcu_read_lock()ed by nf_hook_slow() */
719 afinfo = nf_get_afinfo(family);
720 if (!afinfo)
721 return 0;
722
723 switch (family) {
724 case AF_INET: {
725 struct flowi4 fl1, fl2;
726 struct rtable *rt1, *rt2;
727
728 memset(&fl1, 0, sizeof(fl1));
729 fl1.daddr = src->ip;
730
731 memset(&fl2, 0, sizeof(fl2));
732 fl2.daddr = dst->ip;
733 if (!afinfo->route(&init_net, (struct dst_entry **)&rt1,
734 flowi4_to_flowi(&fl1), false)) {
735 if (!afinfo->route(&init_net, (struct dst_entry **)&rt2,
736 flowi4_to_flowi(&fl2), false)) {
737 if (rt1->rt_gateway == rt2->rt_gateway &&
738 rt1->dst.dev == rt2->dst.dev)
739 ret = 1;
740 dst_release(&rt2->dst);
741 }
742 dst_release(&rt1->dst);
743 }
744 break;
745 }
746 #if defined(CONFIG_NF_CONNTRACK_IPV6) || \
747 defined(CONFIG_NF_CONNTRACK_IPV6_MODULE)
748 case AF_INET6: {
749 struct flowi6 fl1, fl2;
750 struct rt6_info *rt1, *rt2;
751
752 memset(&fl1, 0, sizeof(fl1));
753 ipv6_addr_copy(&fl1.daddr, &src->in6);
754
755 memset(&fl2, 0, sizeof(fl2));
756 ipv6_addr_copy(&fl2.daddr, &dst->in6);
757 if (!afinfo->route(&init_net, (struct dst_entry **)&rt1,
758 flowi6_to_flowi(&fl1), false)) {
759 if (!afinfo->route(&init_net, (struct dst_entry **)&rt2,
760 flowi6_to_flowi(&fl2), false)) {
761 if (!memcmp(&rt1->rt6i_gateway, &rt2->rt6i_gateway,
762 sizeof(rt1->rt6i_gateway)) &&
763 rt1->dst.dev == rt2->dst.dev)
764 ret = 1;
765 dst_release(&rt2->dst);
766 }
767 dst_release(&rt1->dst);
768 }
769 break;
770 }
771 #endif
772 }
773 return ret;
774
775 }
776
777 /****************************************************************************/
778 static int expect_callforwarding(struct sk_buff *skb,
779 struct nf_conn *ct,
780 enum ip_conntrack_info ctinfo,
781 unsigned char **data, int dataoff,
782 TransportAddress *taddr)
783 {
784 int dir = CTINFO2DIR(ctinfo);
785 int ret = 0;
786 __be16 port;
787 union nf_inet_addr addr;
788 struct nf_conntrack_expect *exp;
789 typeof(nat_callforwarding_hook) nat_callforwarding;
790
791 /* Read alternativeAddress */
792 if (!get_h225_addr(ct, *data, taddr, &addr, &port) || port == 0)
793 return 0;
794
795 /* If the calling party is on the same side of the forward-to party,
796 * we don't need to track the second call */
797 if (callforward_filter &&
798 callforward_do_filter(&addr, &ct->tuplehash[!dir].tuple.src.u3,
799 nf_ct_l3num(ct))) {
800 pr_debug("nf_ct_q931: Call Forwarding not tracked\n");
801 return 0;
802 }
803
804 /* Create expect for the second call leg */
805 if ((exp = nf_ct_expect_alloc(ct)) == NULL)
806 return -1;
807 nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
808 &ct->tuplehash[!dir].tuple.src.u3, &addr,
809 IPPROTO_TCP, NULL, &port);
810 exp->helper = nf_conntrack_helper_q931;
811
812 if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
813 &ct->tuplehash[!dir].tuple.dst.u3,
814 sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
815 (nat_callforwarding = rcu_dereference(nat_callforwarding_hook)) &&
816 ct->status & IPS_NAT_MASK) {
817 /* Need NAT */
818 ret = nat_callforwarding(skb, ct, ctinfo, data, dataoff,
819 taddr, port, exp);
820 } else { /* Conntrack only */
821 if (nf_ct_expect_related(exp) == 0) {
822 pr_debug("nf_ct_q931: expect Call Forwarding ");
823 nf_ct_dump_tuple(&exp->tuple);
824 } else
825 ret = -1;
826 }
827
828 nf_ct_expect_put(exp);
829
830 return ret;
831 }
832
833 /****************************************************************************/
834 static int process_setup(struct sk_buff *skb, struct nf_conn *ct,
835 enum ip_conntrack_info ctinfo,
836 unsigned char **data, int dataoff,
837 Setup_UUIE *setup)
838 {
839 int dir = CTINFO2DIR(ctinfo);
840 int ret;
841 int i;
842 __be16 port;
843 union nf_inet_addr addr;
844 typeof(set_h225_addr_hook) set_h225_addr;
845
846 pr_debug("nf_ct_q931: Setup\n");
847
848 if (setup->options & eSetup_UUIE_h245Address) {
849 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
850 &setup->h245Address);
851 if (ret < 0)
852 return -1;
853 }
854
855 set_h225_addr = rcu_dereference(set_h225_addr_hook);
856 if ((setup->options & eSetup_UUIE_destCallSignalAddress) &&
857 (set_h225_addr) && ct->status & IPS_NAT_MASK &&
858 get_h225_addr(ct, *data, &setup->destCallSignalAddress,
859 &addr, &port) &&
860 memcmp(&addr, &ct->tuplehash[!dir].tuple.src.u3, sizeof(addr))) {
861 pr_debug("nf_ct_q931: set destCallSignalAddress %pI6:%hu->%pI6:%hu\n",
862 &addr, ntohs(port), &ct->tuplehash[!dir].tuple.src.u3,
863 ntohs(ct->tuplehash[!dir].tuple.src.u.tcp.port));
864 ret = set_h225_addr(skb, data, dataoff,
865 &setup->destCallSignalAddress,
866 &ct->tuplehash[!dir].tuple.src.u3,
867 ct->tuplehash[!dir].tuple.src.u.tcp.port);
868 if (ret < 0)
869 return -1;
870 }
871
872 if ((setup->options & eSetup_UUIE_sourceCallSignalAddress) &&
873 (set_h225_addr) && ct->status & IPS_NAT_MASK &&
874 get_h225_addr(ct, *data, &setup->sourceCallSignalAddress,
875 &addr, &port) &&
876 memcmp(&addr, &ct->tuplehash[!dir].tuple.dst.u3, sizeof(addr))) {
877 pr_debug("nf_ct_q931: set sourceCallSignalAddress %pI6:%hu->%pI6:%hu\n",
878 &addr, ntohs(port), &ct->tuplehash[!dir].tuple.dst.u3,
879 ntohs(ct->tuplehash[!dir].tuple.dst.u.tcp.port));
880 ret = set_h225_addr(skb, data, dataoff,
881 &setup->sourceCallSignalAddress,
882 &ct->tuplehash[!dir].tuple.dst.u3,
883 ct->tuplehash[!dir].tuple.dst.u.tcp.port);
884 if (ret < 0)
885 return -1;
886 }
887
888 if (setup->options & eSetup_UUIE_fastStart) {
889 for (i = 0; i < setup->fastStart.count; i++) {
890 ret = process_olc(skb, ct, ctinfo, data, dataoff,
891 &setup->fastStart.item[i]);
892 if (ret < 0)
893 return -1;
894 }
895 }
896
897 return 0;
898 }
899
900 /****************************************************************************/
901 static int process_callproceeding(struct sk_buff *skb,
902 struct nf_conn *ct,
903 enum ip_conntrack_info ctinfo,
904 unsigned char **data, int dataoff,
905 CallProceeding_UUIE *callproc)
906 {
907 int ret;
908 int i;
909
910 pr_debug("nf_ct_q931: CallProceeding\n");
911
912 if (callproc->options & eCallProceeding_UUIE_h245Address) {
913 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
914 &callproc->h245Address);
915 if (ret < 0)
916 return -1;
917 }
918
919 if (callproc->options & eCallProceeding_UUIE_fastStart) {
920 for (i = 0; i < callproc->fastStart.count; i++) {
921 ret = process_olc(skb, ct, ctinfo, data, dataoff,
922 &callproc->fastStart.item[i]);
923 if (ret < 0)
924 return -1;
925 }
926 }
927
928 return 0;
929 }
930
931 /****************************************************************************/
932 static int process_connect(struct sk_buff *skb, struct nf_conn *ct,
933 enum ip_conntrack_info ctinfo,
934 unsigned char **data, int dataoff,
935 Connect_UUIE *connect)
936 {
937 int ret;
938 int i;
939
940 pr_debug("nf_ct_q931: Connect\n");
941
942 if (connect->options & eConnect_UUIE_h245Address) {
943 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
944 &connect->h245Address);
945 if (ret < 0)
946 return -1;
947 }
948
949 if (connect->options & eConnect_UUIE_fastStart) {
950 for (i = 0; i < connect->fastStart.count; i++) {
951 ret = process_olc(skb, ct, ctinfo, data, dataoff,
952 &connect->fastStart.item[i]);
953 if (ret < 0)
954 return -1;
955 }
956 }
957
958 return 0;
959 }
960
961 /****************************************************************************/
962 static int process_alerting(struct sk_buff *skb, struct nf_conn *ct,
963 enum ip_conntrack_info ctinfo,
964 unsigned char **data, int dataoff,
965 Alerting_UUIE *alert)
966 {
967 int ret;
968 int i;
969
970 pr_debug("nf_ct_q931: Alerting\n");
971
972 if (alert->options & eAlerting_UUIE_h245Address) {
973 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
974 &alert->h245Address);
975 if (ret < 0)
976 return -1;
977 }
978
979 if (alert->options & eAlerting_UUIE_fastStart) {
980 for (i = 0; i < alert->fastStart.count; i++) {
981 ret = process_olc(skb, ct, ctinfo, data, dataoff,
982 &alert->fastStart.item[i]);
983 if (ret < 0)
984 return -1;
985 }
986 }
987
988 return 0;
989 }
990
991 /****************************************************************************/
992 static int process_facility(struct sk_buff *skb, struct nf_conn *ct,
993 enum ip_conntrack_info ctinfo,
994 unsigned char **data, int dataoff,
995 Facility_UUIE *facility)
996 {
997 int ret;
998 int i;
999
1000 pr_debug("nf_ct_q931: Facility\n");
1001
1002 if (facility->reason.choice == eFacilityReason_callForwarded) {
1003 if (facility->options & eFacility_UUIE_alternativeAddress)
1004 return expect_callforwarding(skb, ct, ctinfo, data,
1005 dataoff,
1006 &facility->
1007 alternativeAddress);
1008 return 0;
1009 }
1010
1011 if (facility->options & eFacility_UUIE_h245Address) {
1012 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
1013 &facility->h245Address);
1014 if (ret < 0)
1015 return -1;
1016 }
1017
1018 if (facility->options & eFacility_UUIE_fastStart) {
1019 for (i = 0; i < facility->fastStart.count; i++) {
1020 ret = process_olc(skb, ct, ctinfo, data, dataoff,
1021 &facility->fastStart.item[i]);
1022 if (ret < 0)
1023 return -1;
1024 }
1025 }
1026
1027 return 0;
1028 }
1029
1030 /****************************************************************************/
1031 static int process_progress(struct sk_buff *skb, struct nf_conn *ct,
1032 enum ip_conntrack_info ctinfo,
1033 unsigned char **data, int dataoff,
1034 Progress_UUIE *progress)
1035 {
1036 int ret;
1037 int i;
1038
1039 pr_debug("nf_ct_q931: Progress\n");
1040
1041 if (progress->options & eProgress_UUIE_h245Address) {
1042 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
1043 &progress->h245Address);
1044 if (ret < 0)
1045 return -1;
1046 }
1047
1048 if (progress->options & eProgress_UUIE_fastStart) {
1049 for (i = 0; i < progress->fastStart.count; i++) {
1050 ret = process_olc(skb, ct, ctinfo, data, dataoff,
1051 &progress->fastStart.item[i]);
1052 if (ret < 0)
1053 return -1;
1054 }
1055 }
1056
1057 return 0;
1058 }
1059
1060 /****************************************************************************/
1061 static int process_q931(struct sk_buff *skb, struct nf_conn *ct,
1062 enum ip_conntrack_info ctinfo,
1063 unsigned char **data, int dataoff, Q931 *q931)
1064 {
1065 H323_UU_PDU *pdu = &q931->UUIE.h323_uu_pdu;
1066 int i;
1067 int ret = 0;
1068
1069 switch (pdu->h323_message_body.choice) {
1070 case eH323_UU_PDU_h323_message_body_setup:
1071 ret = process_setup(skb, ct, ctinfo, data, dataoff,
1072 &pdu->h323_message_body.setup);
1073 break;
1074 case eH323_UU_PDU_h323_message_body_callProceeding:
1075 ret = process_callproceeding(skb, ct, ctinfo, data, dataoff,
1076 &pdu->h323_message_body.
1077 callProceeding);
1078 break;
1079 case eH323_UU_PDU_h323_message_body_connect:
1080 ret = process_connect(skb, ct, ctinfo, data, dataoff,
1081 &pdu->h323_message_body.connect);
1082 break;
1083 case eH323_UU_PDU_h323_message_body_alerting:
1084 ret = process_alerting(skb, ct, ctinfo, data, dataoff,
1085 &pdu->h323_message_body.alerting);
1086 break;
1087 case eH323_UU_PDU_h323_message_body_facility:
1088 ret = process_facility(skb, ct, ctinfo, data, dataoff,
1089 &pdu->h323_message_body.facility);
1090 break;
1091 case eH323_UU_PDU_h323_message_body_progress:
1092 ret = process_progress(skb, ct, ctinfo, data, dataoff,
1093 &pdu->h323_message_body.progress);
1094 break;
1095 default:
1096 pr_debug("nf_ct_q931: Q.931 signal %d\n",
1097 pdu->h323_message_body.choice);
1098 break;
1099 }
1100
1101 if (ret < 0)
1102 return -1;
1103
1104 if (pdu->options & eH323_UU_PDU_h245Control) {
1105 for (i = 0; i < pdu->h245Control.count; i++) {
1106 ret = process_h245(skb, ct, ctinfo, data, dataoff,
1107 &pdu->h245Control.item[i]);
1108 if (ret < 0)
1109 return -1;
1110 }
1111 }
1112
1113 return 0;
1114 }
1115
1116 /****************************************************************************/
1117 static int q931_help(struct sk_buff *skb, unsigned int protoff,
1118 struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1119 {
1120 static Q931 q931;
1121 unsigned char *data = NULL;
1122 int datalen;
1123 int dataoff;
1124 int ret;
1125
1126 /* Until there's been traffic both ways, don't look in packets. */
1127 if (ctinfo != IP_CT_ESTABLISHED && ctinfo != IP_CT_ESTABLISHED_REPLY)
1128 return NF_ACCEPT;
1129
1130 pr_debug("nf_ct_q931: skblen = %u\n", skb->len);
1131
1132 spin_lock_bh(&nf_h323_lock);
1133
1134 /* Process each TPKT */
1135 while (get_tpkt_data(skb, protoff, ct, ctinfo,
1136 &data, &datalen, &dataoff)) {
1137 pr_debug("nf_ct_q931: TPKT len=%d ", datalen);
1138 nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1139
1140 /* Decode Q.931 signal */
1141 ret = DecodeQ931(data, datalen, &q931);
1142 if (ret < 0) {
1143 pr_debug("nf_ct_q931: decoding error: %s\n",
1144 ret == H323_ERROR_BOUND ?
1145 "out of bound" : "out of range");
1146 /* We don't drop when decoding error */
1147 break;
1148 }
1149
1150 /* Process Q.931 signal */
1151 if (process_q931(skb, ct, ctinfo, &data, dataoff, &q931) < 0)
1152 goto drop;
1153 }
1154
1155 spin_unlock_bh(&nf_h323_lock);
1156 return NF_ACCEPT;
1157
1158 drop:
1159 spin_unlock_bh(&nf_h323_lock);
1160 if (net_ratelimit())
1161 pr_info("nf_ct_q931: packet dropped\n");
1162 return NF_DROP;
1163 }
1164
1165 /****************************************************************************/
1166 static const struct nf_conntrack_expect_policy q931_exp_policy = {
1167 /* T.120 and H.245 */
1168 .max_expected = H323_RTP_CHANNEL_MAX * 4 + 4,
1169 .timeout = 240,
1170 };
1171
1172 static struct nf_conntrack_helper nf_conntrack_helper_q931[] __read_mostly = {
1173 {
1174 .name = "Q.931",
1175 .me = THIS_MODULE,
1176 .tuple.src.l3num = AF_INET,
1177 .tuple.src.u.tcp.port = cpu_to_be16(Q931_PORT),
1178 .tuple.dst.protonum = IPPROTO_TCP,
1179 .help = q931_help,
1180 .expect_policy = &q931_exp_policy,
1181 },
1182 {
1183 .name = "Q.931",
1184 .me = THIS_MODULE,
1185 .tuple.src.l3num = AF_INET6,
1186 .tuple.src.u.tcp.port = cpu_to_be16(Q931_PORT),
1187 .tuple.dst.protonum = IPPROTO_TCP,
1188 .help = q931_help,
1189 .expect_policy = &q931_exp_policy,
1190 },
1191 };
1192
1193 /****************************************************************************/
1194 static unsigned char *get_udp_data(struct sk_buff *skb, unsigned int protoff,
1195 int *datalen)
1196 {
1197 const struct udphdr *uh;
1198 struct udphdr _uh;
1199 int dataoff;
1200
1201 uh = skb_header_pointer(skb, protoff, sizeof(_uh), &_uh);
1202 if (uh == NULL)
1203 return NULL;
1204 dataoff = protoff + sizeof(_uh);
1205 if (dataoff >= skb->len)
1206 return NULL;
1207 *datalen = skb->len - dataoff;
1208 return skb_header_pointer(skb, dataoff, *datalen, h323_buffer);
1209 }
1210
1211 /****************************************************************************/
1212 static struct nf_conntrack_expect *find_expect(struct nf_conn *ct,
1213 union nf_inet_addr *addr,
1214 __be16 port)
1215 {
1216 struct net *net = nf_ct_net(ct);
1217 struct nf_conntrack_expect *exp;
1218 struct nf_conntrack_tuple tuple;
1219
1220 memset(&tuple.src.u3, 0, sizeof(tuple.src.u3));
1221 tuple.src.u.tcp.port = 0;
1222 memcpy(&tuple.dst.u3, addr, sizeof(tuple.dst.u3));
1223 tuple.dst.u.tcp.port = port;
1224 tuple.dst.protonum = IPPROTO_TCP;
1225
1226 exp = __nf_ct_expect_find(net, nf_ct_zone(ct), &tuple);
1227 if (exp && exp->master == ct)
1228 return exp;
1229 return NULL;
1230 }
1231
1232 /****************************************************************************/
1233 static int set_expect_timeout(struct nf_conntrack_expect *exp,
1234 unsigned timeout)
1235 {
1236 if (!exp || !del_timer(&exp->timeout))
1237 return 0;
1238
1239 exp->timeout.expires = jiffies + timeout * HZ;
1240 add_timer(&exp->timeout);
1241
1242 return 1;
1243 }
1244
1245 /****************************************************************************/
1246 static int expect_q931(struct sk_buff *skb, struct nf_conn *ct,
1247 enum ip_conntrack_info ctinfo,
1248 unsigned char **data,
1249 TransportAddress *taddr, int count)
1250 {
1251 struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1252 int dir = CTINFO2DIR(ctinfo);
1253 int ret = 0;
1254 int i;
1255 __be16 port;
1256 union nf_inet_addr addr;
1257 struct nf_conntrack_expect *exp;
1258 typeof(nat_q931_hook) nat_q931;
1259
1260 /* Look for the first related address */
1261 for (i = 0; i < count; i++) {
1262 if (get_h225_addr(ct, *data, &taddr[i], &addr, &port) &&
1263 memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3,
1264 sizeof(addr)) == 0 && port != 0)
1265 break;
1266 }
1267
1268 if (i >= count) /* Not found */
1269 return 0;
1270
1271 /* Create expect for Q.931 */
1272 if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1273 return -1;
1274 nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1275 gkrouted_only ? /* only accept calls from GK? */
1276 &ct->tuplehash[!dir].tuple.src.u3 : NULL,
1277 &ct->tuplehash[!dir].tuple.dst.u3,
1278 IPPROTO_TCP, NULL, &port);
1279 exp->helper = nf_conntrack_helper_q931;
1280 exp->flags = NF_CT_EXPECT_PERMANENT; /* Accept multiple calls */
1281
1282 nat_q931 = rcu_dereference(nat_q931_hook);
1283 if (nat_q931 && ct->status & IPS_NAT_MASK) { /* Need NAT */
1284 ret = nat_q931(skb, ct, ctinfo, data, taddr, i, port, exp);
1285 } else { /* Conntrack only */
1286 if (nf_ct_expect_related(exp) == 0) {
1287 pr_debug("nf_ct_ras: expect Q.931 ");
1288 nf_ct_dump_tuple(&exp->tuple);
1289
1290 /* Save port for looking up expect in processing RCF */
1291 info->sig_port[dir] = port;
1292 } else
1293 ret = -1;
1294 }
1295
1296 nf_ct_expect_put(exp);
1297
1298 return ret;
1299 }
1300
1301 /****************************************************************************/
1302 static int process_grq(struct sk_buff *skb, struct nf_conn *ct,
1303 enum ip_conntrack_info ctinfo,
1304 unsigned char **data, GatekeeperRequest *grq)
1305 {
1306 typeof(set_ras_addr_hook) set_ras_addr;
1307
1308 pr_debug("nf_ct_ras: GRQ\n");
1309
1310 set_ras_addr = rcu_dereference(set_ras_addr_hook);
1311 if (set_ras_addr && ct->status & IPS_NAT_MASK) /* NATed */
1312 return set_ras_addr(skb, ct, ctinfo, data,
1313 &grq->rasAddress, 1);
1314 return 0;
1315 }
1316
1317 /****************************************************************************/
1318 static int process_gcf(struct sk_buff *skb, struct nf_conn *ct,
1319 enum ip_conntrack_info ctinfo,
1320 unsigned char **data, GatekeeperConfirm *gcf)
1321 {
1322 int dir = CTINFO2DIR(ctinfo);
1323 int ret = 0;
1324 __be16 port;
1325 union nf_inet_addr addr;
1326 struct nf_conntrack_expect *exp;
1327
1328 pr_debug("nf_ct_ras: GCF\n");
1329
1330 if (!get_h225_addr(ct, *data, &gcf->rasAddress, &addr, &port))
1331 return 0;
1332
1333 /* Registration port is the same as discovery port */
1334 if (!memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1335 port == ct->tuplehash[dir].tuple.src.u.udp.port)
1336 return 0;
1337
1338 /* Avoid RAS expectation loops. A GCF is never expected. */
1339 if (test_bit(IPS_EXPECTED_BIT, &ct->status))
1340 return 0;
1341
1342 /* Need new expect */
1343 if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1344 return -1;
1345 nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1346 &ct->tuplehash[!dir].tuple.src.u3, &addr,
1347 IPPROTO_UDP, NULL, &port);
1348 exp->helper = nf_conntrack_helper_ras;
1349
1350 if (nf_ct_expect_related(exp) == 0) {
1351 pr_debug("nf_ct_ras: expect RAS ");
1352 nf_ct_dump_tuple(&exp->tuple);
1353 } else
1354 ret = -1;
1355
1356 nf_ct_expect_put(exp);
1357
1358 return ret;
1359 }
1360
1361 /****************************************************************************/
1362 static int process_rrq(struct sk_buff *skb, struct nf_conn *ct,
1363 enum ip_conntrack_info ctinfo,
1364 unsigned char **data, RegistrationRequest *rrq)
1365 {
1366 struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1367 int ret;
1368 typeof(set_ras_addr_hook) set_ras_addr;
1369
1370 pr_debug("nf_ct_ras: RRQ\n");
1371
1372 ret = expect_q931(skb, ct, ctinfo, data,
1373 rrq->callSignalAddress.item,
1374 rrq->callSignalAddress.count);
1375 if (ret < 0)
1376 return -1;
1377
1378 set_ras_addr = rcu_dereference(set_ras_addr_hook);
1379 if (set_ras_addr && ct->status & IPS_NAT_MASK) {
1380 ret = set_ras_addr(skb, ct, ctinfo, data,
1381 rrq->rasAddress.item,
1382 rrq->rasAddress.count);
1383 if (ret < 0)
1384 return -1;
1385 }
1386
1387 if (rrq->options & eRegistrationRequest_timeToLive) {
1388 pr_debug("nf_ct_ras: RRQ TTL = %u seconds\n", rrq->timeToLive);
1389 info->timeout = rrq->timeToLive;
1390 } else
1391 info->timeout = default_rrq_ttl;
1392
1393 return 0;
1394 }
1395
1396 /****************************************************************************/
1397 static int process_rcf(struct sk_buff *skb, struct nf_conn *ct,
1398 enum ip_conntrack_info ctinfo,
1399 unsigned char **data, RegistrationConfirm *rcf)
1400 {
1401 struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1402 int dir = CTINFO2DIR(ctinfo);
1403 int ret;
1404 struct nf_conntrack_expect *exp;
1405 typeof(set_sig_addr_hook) set_sig_addr;
1406
1407 pr_debug("nf_ct_ras: RCF\n");
1408
1409 set_sig_addr = rcu_dereference(set_sig_addr_hook);
1410 if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1411 ret = set_sig_addr(skb, ct, ctinfo, data,
1412 rcf->callSignalAddress.item,
1413 rcf->callSignalAddress.count);
1414 if (ret < 0)
1415 return -1;
1416 }
1417
1418 if (rcf->options & eRegistrationConfirm_timeToLive) {
1419 pr_debug("nf_ct_ras: RCF TTL = %u seconds\n", rcf->timeToLive);
1420 info->timeout = rcf->timeToLive;
1421 }
1422
1423 if (info->timeout > 0) {
1424 pr_debug("nf_ct_ras: set RAS connection timeout to "
1425 "%u seconds\n", info->timeout);
1426 nf_ct_refresh(ct, skb, info->timeout * HZ);
1427
1428 /* Set expect timeout */
1429 spin_lock_bh(&nf_conntrack_lock);
1430 exp = find_expect(ct, &ct->tuplehash[dir].tuple.dst.u3,
1431 info->sig_port[!dir]);
1432 if (exp) {
1433 pr_debug("nf_ct_ras: set Q.931 expect "
1434 "timeout to %u seconds for",
1435 info->timeout);
1436 nf_ct_dump_tuple(&exp->tuple);
1437 set_expect_timeout(exp, info->timeout);
1438 }
1439 spin_unlock_bh(&nf_conntrack_lock);
1440 }
1441
1442 return 0;
1443 }
1444
1445 /****************************************************************************/
1446 static int process_urq(struct sk_buff *skb, struct nf_conn *ct,
1447 enum ip_conntrack_info ctinfo,
1448 unsigned char **data, UnregistrationRequest *urq)
1449 {
1450 struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1451 int dir = CTINFO2DIR(ctinfo);
1452 int ret;
1453 typeof(set_sig_addr_hook) set_sig_addr;
1454
1455 pr_debug("nf_ct_ras: URQ\n");
1456
1457 set_sig_addr = rcu_dereference(set_sig_addr_hook);
1458 if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1459 ret = set_sig_addr(skb, ct, ctinfo, data,
1460 urq->callSignalAddress.item,
1461 urq->callSignalAddress.count);
1462 if (ret < 0)
1463 return -1;
1464 }
1465
1466 /* Clear old expect */
1467 nf_ct_remove_expectations(ct);
1468 info->sig_port[dir] = 0;
1469 info->sig_port[!dir] = 0;
1470
1471 /* Give it 30 seconds for UCF or URJ */
1472 nf_ct_refresh(ct, skb, 30 * HZ);
1473
1474 return 0;
1475 }
1476
1477 /****************************************************************************/
1478 static int process_arq(struct sk_buff *skb, struct nf_conn *ct,
1479 enum ip_conntrack_info ctinfo,
1480 unsigned char **data, AdmissionRequest *arq)
1481 {
1482 const struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1483 int dir = CTINFO2DIR(ctinfo);
1484 __be16 port;
1485 union nf_inet_addr addr;
1486 typeof(set_h225_addr_hook) set_h225_addr;
1487
1488 pr_debug("nf_ct_ras: ARQ\n");
1489
1490 set_h225_addr = rcu_dereference(set_h225_addr_hook);
1491 if ((arq->options & eAdmissionRequest_destCallSignalAddress) &&
1492 get_h225_addr(ct, *data, &arq->destCallSignalAddress,
1493 &addr, &port) &&
1494 !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1495 port == info->sig_port[dir] &&
1496 set_h225_addr && ct->status & IPS_NAT_MASK) {
1497 /* Answering ARQ */
1498 return set_h225_addr(skb, data, 0,
1499 &arq->destCallSignalAddress,
1500 &ct->tuplehash[!dir].tuple.dst.u3,
1501 info->sig_port[!dir]);
1502 }
1503
1504 if ((arq->options & eAdmissionRequest_srcCallSignalAddress) &&
1505 get_h225_addr(ct, *data, &arq->srcCallSignalAddress,
1506 &addr, &port) &&
1507 !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1508 set_h225_addr && ct->status & IPS_NAT_MASK) {
1509 /* Calling ARQ */
1510 return set_h225_addr(skb, data, 0,
1511 &arq->srcCallSignalAddress,
1512 &ct->tuplehash[!dir].tuple.dst.u3,
1513 port);
1514 }
1515
1516 return 0;
1517 }
1518
1519 /****************************************************************************/
1520 static int process_acf(struct sk_buff *skb, struct nf_conn *ct,
1521 enum ip_conntrack_info ctinfo,
1522 unsigned char **data, AdmissionConfirm *acf)
1523 {
1524 int dir = CTINFO2DIR(ctinfo);
1525 int ret = 0;
1526 __be16 port;
1527 union nf_inet_addr addr;
1528 struct nf_conntrack_expect *exp;
1529 typeof(set_sig_addr_hook) set_sig_addr;
1530
1531 pr_debug("nf_ct_ras: ACF\n");
1532
1533 if (!get_h225_addr(ct, *data, &acf->destCallSignalAddress,
1534 &addr, &port))
1535 return 0;
1536
1537 if (!memcmp(&addr, &ct->tuplehash[dir].tuple.dst.u3, sizeof(addr))) {
1538 /* Answering ACF */
1539 set_sig_addr = rcu_dereference(set_sig_addr_hook);
1540 if (set_sig_addr && ct->status & IPS_NAT_MASK)
1541 return set_sig_addr(skb, ct, ctinfo, data,
1542 &acf->destCallSignalAddress, 1);
1543 return 0;
1544 }
1545
1546 /* Need new expect */
1547 if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1548 return -1;
1549 nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1550 &ct->tuplehash[!dir].tuple.src.u3, &addr,
1551 IPPROTO_TCP, NULL, &port);
1552 exp->flags = NF_CT_EXPECT_PERMANENT;
1553 exp->helper = nf_conntrack_helper_q931;
1554
1555 if (nf_ct_expect_related(exp) == 0) {
1556 pr_debug("nf_ct_ras: expect Q.931 ");
1557 nf_ct_dump_tuple(&exp->tuple);
1558 } else
1559 ret = -1;
1560
1561 nf_ct_expect_put(exp);
1562
1563 return ret;
1564 }
1565
1566 /****************************************************************************/
1567 static int process_lrq(struct sk_buff *skb, struct nf_conn *ct,
1568 enum ip_conntrack_info ctinfo,
1569 unsigned char **data, LocationRequest *lrq)
1570 {
1571 typeof(set_ras_addr_hook) set_ras_addr;
1572
1573 pr_debug("nf_ct_ras: LRQ\n");
1574
1575 set_ras_addr = rcu_dereference(set_ras_addr_hook);
1576 if (set_ras_addr && ct->status & IPS_NAT_MASK)
1577 return set_ras_addr(skb, ct, ctinfo, data,
1578 &lrq->replyAddress, 1);
1579 return 0;
1580 }
1581
1582 /****************************************************************************/
1583 static int process_lcf(struct sk_buff *skb, struct nf_conn *ct,
1584 enum ip_conntrack_info ctinfo,
1585 unsigned char **data, LocationConfirm *lcf)
1586 {
1587 int dir = CTINFO2DIR(ctinfo);
1588 int ret = 0;
1589 __be16 port;
1590 union nf_inet_addr addr;
1591 struct nf_conntrack_expect *exp;
1592
1593 pr_debug("nf_ct_ras: LCF\n");
1594
1595 if (!get_h225_addr(ct, *data, &lcf->callSignalAddress,
1596 &addr, &port))
1597 return 0;
1598
1599 /* Need new expect for call signal */
1600 if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1601 return -1;
1602 nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1603 &ct->tuplehash[!dir].tuple.src.u3, &addr,
1604 IPPROTO_TCP, NULL, &port);
1605 exp->flags = NF_CT_EXPECT_PERMANENT;
1606 exp->helper = nf_conntrack_helper_q931;
1607
1608 if (nf_ct_expect_related(exp) == 0) {
1609 pr_debug("nf_ct_ras: expect Q.931 ");
1610 nf_ct_dump_tuple(&exp->tuple);
1611 } else
1612 ret = -1;
1613
1614 nf_ct_expect_put(exp);
1615
1616 /* Ignore rasAddress */
1617
1618 return ret;
1619 }
1620
1621 /****************************************************************************/
1622 static int process_irr(struct sk_buff *skb, struct nf_conn *ct,
1623 enum ip_conntrack_info ctinfo,
1624 unsigned char **data, InfoRequestResponse *irr)
1625 {
1626 int ret;
1627 typeof(set_ras_addr_hook) set_ras_addr;
1628 typeof(set_sig_addr_hook) set_sig_addr;
1629
1630 pr_debug("nf_ct_ras: IRR\n");
1631
1632 set_ras_addr = rcu_dereference(set_ras_addr_hook);
1633 if (set_ras_addr && ct->status & IPS_NAT_MASK) {
1634 ret = set_ras_addr(skb, ct, ctinfo, data,
1635 &irr->rasAddress, 1);
1636 if (ret < 0)
1637 return -1;
1638 }
1639
1640 set_sig_addr = rcu_dereference(set_sig_addr_hook);
1641 if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1642 ret = set_sig_addr(skb, ct, ctinfo, data,
1643 irr->callSignalAddress.item,
1644 irr->callSignalAddress.count);
1645 if (ret < 0)
1646 return -1;
1647 }
1648
1649 return 0;
1650 }
1651
1652 /****************************************************************************/
1653 static int process_ras(struct sk_buff *skb, struct nf_conn *ct,
1654 enum ip_conntrack_info ctinfo,
1655 unsigned char **data, RasMessage *ras)
1656 {
1657 switch (ras->choice) {
1658 case eRasMessage_gatekeeperRequest:
1659 return process_grq(skb, ct, ctinfo, data,
1660 &ras->gatekeeperRequest);
1661 case eRasMessage_gatekeeperConfirm:
1662 return process_gcf(skb, ct, ctinfo, data,
1663 &ras->gatekeeperConfirm);
1664 case eRasMessage_registrationRequest:
1665 return process_rrq(skb, ct, ctinfo, data,
1666 &ras->registrationRequest);
1667 case eRasMessage_registrationConfirm:
1668 return process_rcf(skb, ct, ctinfo, data,
1669 &ras->registrationConfirm);
1670 case eRasMessage_unregistrationRequest:
1671 return process_urq(skb, ct, ctinfo, data,
1672 &ras->unregistrationRequest);
1673 case eRasMessage_admissionRequest:
1674 return process_arq(skb, ct, ctinfo, data,
1675 &ras->admissionRequest);
1676 case eRasMessage_admissionConfirm:
1677 return process_acf(skb, ct, ctinfo, data,
1678 &ras->admissionConfirm);
1679 case eRasMessage_locationRequest:
1680 return process_lrq(skb, ct, ctinfo, data,
1681 &ras->locationRequest);
1682 case eRasMessage_locationConfirm:
1683 return process_lcf(skb, ct, ctinfo, data,
1684 &ras->locationConfirm);
1685 case eRasMessage_infoRequestResponse:
1686 return process_irr(skb, ct, ctinfo, data,
1687 &ras->infoRequestResponse);
1688 default:
1689 pr_debug("nf_ct_ras: RAS message %d\n", ras->choice);
1690 break;
1691 }
1692
1693 return 0;
1694 }
1695
1696 /****************************************************************************/
1697 static int ras_help(struct sk_buff *skb, unsigned int protoff,
1698 struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1699 {
1700 static RasMessage ras;
1701 unsigned char *data;
1702 int datalen = 0;
1703 int ret;
1704
1705 pr_debug("nf_ct_ras: skblen = %u\n", skb->len);
1706
1707 spin_lock_bh(&nf_h323_lock);
1708
1709 /* Get UDP data */
1710 data = get_udp_data(skb, protoff, &datalen);
1711 if (data == NULL)
1712 goto accept;
1713 pr_debug("nf_ct_ras: RAS message len=%d ", datalen);
1714 nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1715
1716 /* Decode RAS message */
1717 ret = DecodeRasMessage(data, datalen, &ras);
1718 if (ret < 0) {
1719 pr_debug("nf_ct_ras: decoding error: %s\n",
1720 ret == H323_ERROR_BOUND ?
1721 "out of bound" : "out of range");
1722 goto accept;
1723 }
1724
1725 /* Process RAS message */
1726 if (process_ras(skb, ct, ctinfo, &data, &ras) < 0)
1727 goto drop;
1728
1729 accept:
1730 spin_unlock_bh(&nf_h323_lock);
1731 return NF_ACCEPT;
1732
1733 drop:
1734 spin_unlock_bh(&nf_h323_lock);
1735 if (net_ratelimit())
1736 pr_info("nf_ct_ras: packet dropped\n");
1737 return NF_DROP;
1738 }
1739
1740 /****************************************************************************/
1741 static const struct nf_conntrack_expect_policy ras_exp_policy = {
1742 .max_expected = 32,
1743 .timeout = 240,
1744 };
1745
1746 static struct nf_conntrack_helper nf_conntrack_helper_ras[] __read_mostly = {
1747 {
1748 .name = "RAS",
1749 .me = THIS_MODULE,
1750 .tuple.src.l3num = AF_INET,
1751 .tuple.src.u.udp.port = cpu_to_be16(RAS_PORT),
1752 .tuple.dst.protonum = IPPROTO_UDP,
1753 .help = ras_help,
1754 .expect_policy = &ras_exp_policy,
1755 },
1756 {
1757 .name = "RAS",
1758 .me = THIS_MODULE,
1759 .tuple.src.l3num = AF_INET6,
1760 .tuple.src.u.udp.port = cpu_to_be16(RAS_PORT),
1761 .tuple.dst.protonum = IPPROTO_UDP,
1762 .help = ras_help,
1763 .expect_policy = &ras_exp_policy,
1764 },
1765 };
1766
1767 /****************************************************************************/
1768 static void __exit nf_conntrack_h323_fini(void)
1769 {
1770 nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[1]);
1771 nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1772 nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1773 nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1774 nf_conntrack_helper_unregister(&nf_conntrack_helper_h245);
1775 kfree(h323_buffer);
1776 pr_debug("nf_ct_h323: fini\n");
1777 }
1778
1779 /****************************************************************************/
1780 static int __init nf_conntrack_h323_init(void)
1781 {
1782 int ret;
1783
1784 h323_buffer = kmalloc(65536, GFP_KERNEL);
1785 if (!h323_buffer)
1786 return -ENOMEM;
1787 ret = nf_conntrack_helper_register(&nf_conntrack_helper_h245);
1788 if (ret < 0)
1789 goto err1;
1790 ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[0]);
1791 if (ret < 0)
1792 goto err2;
1793 ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[1]);
1794 if (ret < 0)
1795 goto err3;
1796 ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[0]);
1797 if (ret < 0)
1798 goto err4;
1799 ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[1]);
1800 if (ret < 0)
1801 goto err5;
1802 pr_debug("nf_ct_h323: init success\n");
1803 return 0;
1804
1805 err5:
1806 nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1807 err4:
1808 nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1809 err3:
1810 nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1811 err2:
1812 nf_conntrack_helper_unregister(&nf_conntrack_helper_h245);
1813 err1:
1814 kfree(h323_buffer);
1815 return ret;
1816 }
1817
1818 /****************************************************************************/
1819 module_init(nf_conntrack_h323_init);
1820 module_exit(nf_conntrack_h323_fini);
1821
1822 EXPORT_SYMBOL_GPL(get_h225_addr);
1823 EXPORT_SYMBOL_GPL(set_h245_addr_hook);
1824 EXPORT_SYMBOL_GPL(set_h225_addr_hook);
1825 EXPORT_SYMBOL_GPL(set_sig_addr_hook);
1826 EXPORT_SYMBOL_GPL(set_ras_addr_hook);
1827 EXPORT_SYMBOL_GPL(nat_rtp_rtcp_hook);
1828 EXPORT_SYMBOL_GPL(nat_t120_hook);
1829 EXPORT_SYMBOL_GPL(nat_h245_hook);
1830 EXPORT_SYMBOL_GPL(nat_callforwarding_hook);
1831 EXPORT_SYMBOL_GPL(nat_q931_hook);
1832
1833 MODULE_AUTHOR("Jing Min Zhao <zhaojingmin@users.sourceforge.net>");
1834 MODULE_DESCRIPTION("H.323 connection tracking helper");
1835 MODULE_LICENSE("GPL");
1836 MODULE_ALIAS("ip_conntrack_h323");
1837 MODULE_ALIAS_NFCT_HELPER("h323");
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree