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clk: mxs: imx28: decrease the frequency of ref_io1 for SSP2 and SSP3
[deliverable/linux.git] / net / netfilter / nf_conntrack_h323_main.c
1 /*
2 * H.323 connection tracking helper
3 *
4 * Copyright (c) 2006 Jing Min Zhao <zhaojingmin@users.sourceforge.net>
5 *
6 * This source code is licensed under General Public License version 2.
7 *
8 * Based on the 'brute force' H.323 connection tracking module by
9 * Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
10 *
11 * For more information, please see http://nath323.sourceforge.net/
12 */
13
14 #include <linux/module.h>
15 #include <linux/moduleparam.h>
16 #include <linux/ctype.h>
17 #include <linux/inet.h>
18 #include <linux/in.h>
19 #include <linux/ip.h>
20 #include <linux/slab.h>
21 #include <linux/udp.h>
22 #include <linux/tcp.h>
23 #include <linux/skbuff.h>
24 #include <net/route.h>
25 #include <net/ip6_route.h>
26
27 #include <net/netfilter/nf_conntrack.h>
28 #include <net/netfilter/nf_conntrack_core.h>
29 #include <net/netfilter/nf_conntrack_tuple.h>
30 #include <net/netfilter/nf_conntrack_expect.h>
31 #include <net/netfilter/nf_conntrack_ecache.h>
32 #include <net/netfilter/nf_conntrack_helper.h>
33 #include <net/netfilter/nf_conntrack_zones.h>
34 #include <linux/netfilter/nf_conntrack_h323.h>
35
36 /* Parameters */
37 static unsigned int default_rrq_ttl __read_mostly = 300;
38 module_param(default_rrq_ttl, uint, 0600);
39 MODULE_PARM_DESC(default_rrq_ttl, "use this TTL if it's missing in RRQ");
40
41 static int gkrouted_only __read_mostly = 1;
42 module_param(gkrouted_only, int, 0600);
43 MODULE_PARM_DESC(gkrouted_only, "only accept calls from gatekeeper");
44
45 static bool callforward_filter __read_mostly = true;
46 module_param(callforward_filter, bool, 0600);
47 MODULE_PARM_DESC(callforward_filter, "only create call forwarding expectations "
48 "if both endpoints are on different sides "
49 "(determined by routing information)");
50
51 /* Hooks for NAT */
52 int (*set_h245_addr_hook) (struct sk_buff *skb,
53 unsigned char **data, int dataoff,
54 H245_TransportAddress *taddr,
55 union nf_inet_addr *addr, __be16 port)
56 __read_mostly;
57 int (*set_h225_addr_hook) (struct sk_buff *skb,
58 unsigned char **data, int dataoff,
59 TransportAddress *taddr,
60 union nf_inet_addr *addr, __be16 port)
61 __read_mostly;
62 int (*set_sig_addr_hook) (struct sk_buff *skb,
63 struct nf_conn *ct,
64 enum ip_conntrack_info ctinfo,
65 unsigned char **data,
66 TransportAddress *taddr, int count) __read_mostly;
67 int (*set_ras_addr_hook) (struct sk_buff *skb,
68 struct nf_conn *ct,
69 enum ip_conntrack_info ctinfo,
70 unsigned char **data,
71 TransportAddress *taddr, int count) __read_mostly;
72 int (*nat_rtp_rtcp_hook) (struct sk_buff *skb,
73 struct nf_conn *ct,
74 enum ip_conntrack_info ctinfo,
75 unsigned char **data, int dataoff,
76 H245_TransportAddress *taddr,
77 __be16 port, __be16 rtp_port,
78 struct nf_conntrack_expect *rtp_exp,
79 struct nf_conntrack_expect *rtcp_exp) __read_mostly;
80 int (*nat_t120_hook) (struct sk_buff *skb,
81 struct nf_conn *ct,
82 enum ip_conntrack_info ctinfo,
83 unsigned char **data, int dataoff,
84 H245_TransportAddress *taddr, __be16 port,
85 struct nf_conntrack_expect *exp) __read_mostly;
86 int (*nat_h245_hook) (struct sk_buff *skb,
87 struct nf_conn *ct,
88 enum ip_conntrack_info ctinfo,
89 unsigned char **data, int dataoff,
90 TransportAddress *taddr, __be16 port,
91 struct nf_conntrack_expect *exp) __read_mostly;
92 int (*nat_callforwarding_hook) (struct sk_buff *skb,
93 struct nf_conn *ct,
94 enum ip_conntrack_info ctinfo,
95 unsigned char **data, int dataoff,
96 TransportAddress *taddr, __be16 port,
97 struct nf_conntrack_expect *exp) __read_mostly;
98 int (*nat_q931_hook) (struct sk_buff *skb,
99 struct nf_conn *ct,
100 enum ip_conntrack_info ctinfo,
101 unsigned char **data, TransportAddress *taddr, int idx,
102 __be16 port, struct nf_conntrack_expect *exp)
103 __read_mostly;
104
105 static DEFINE_SPINLOCK(nf_h323_lock);
106 static char *h323_buffer;
107
108 static struct nf_conntrack_helper nf_conntrack_helper_h245;
109 static struct nf_conntrack_helper nf_conntrack_helper_q931[];
110 static struct nf_conntrack_helper nf_conntrack_helper_ras[];
111
112 /****************************************************************************/
113 static int get_tpkt_data(struct sk_buff *skb, unsigned int protoff,
114 struct nf_conn *ct, enum ip_conntrack_info ctinfo,
115 unsigned char **data, int *datalen, int *dataoff)
116 {
117 struct nf_ct_h323_master *info = &nfct_help(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 net_info_ratelimited("nf_ct_h245: packet dropped\n");
609 return NF_DROP;
610 }
611
612 /****************************************************************************/
613 static const struct nf_conntrack_expect_policy h245_exp_policy = {
614 .max_expected = H323_RTP_CHANNEL_MAX * 4 + 2 /* T.120 */,
615 .timeout = 240,
616 };
617
618 static struct nf_conntrack_helper nf_conntrack_helper_h245 __read_mostly = {
619 .name = "H.245",
620 .me = THIS_MODULE,
621 .tuple.src.l3num = AF_UNSPEC,
622 .tuple.dst.protonum = IPPROTO_UDP,
623 .help = h245_help,
624 .expect_policy = &h245_exp_policy,
625 };
626
627 /****************************************************************************/
628 int get_h225_addr(struct nf_conn *ct, unsigned char *data,
629 TransportAddress *taddr,
630 union nf_inet_addr *addr, __be16 *port)
631 {
632 const unsigned char *p;
633 int len;
634
635 switch (taddr->choice) {
636 case eTransportAddress_ipAddress:
637 if (nf_ct_l3num(ct) != AF_INET)
638 return 0;
639 p = data + taddr->ipAddress.ip;
640 len = 4;
641 break;
642 case eTransportAddress_ip6Address:
643 if (nf_ct_l3num(ct) != AF_INET6)
644 return 0;
645 p = data + taddr->ip6Address.ip;
646 len = 16;
647 break;
648 default:
649 return 0;
650 }
651
652 memcpy(addr, p, len);
653 memset((void *)addr + len, 0, sizeof(*addr) - len);
654 memcpy(port, p + len, sizeof(__be16));
655
656 return 1;
657 }
658
659 /****************************************************************************/
660 static int expect_h245(struct sk_buff *skb, struct nf_conn *ct,
661 enum ip_conntrack_info ctinfo,
662 unsigned char **data, int dataoff,
663 TransportAddress *taddr)
664 {
665 int dir = CTINFO2DIR(ctinfo);
666 int ret = 0;
667 __be16 port;
668 union nf_inet_addr addr;
669 struct nf_conntrack_expect *exp;
670 typeof(nat_h245_hook) nat_h245;
671
672 /* Read h245Address */
673 if (!get_h225_addr(ct, *data, taddr, &addr, &port) ||
674 memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
675 port == 0)
676 return 0;
677
678 /* Create expect for h245 connection */
679 if ((exp = nf_ct_expect_alloc(ct)) == NULL)
680 return -1;
681 nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
682 &ct->tuplehash[!dir].tuple.src.u3,
683 &ct->tuplehash[!dir].tuple.dst.u3,
684 IPPROTO_TCP, NULL, &port);
685 exp->helper = &nf_conntrack_helper_h245;
686
687 if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
688 &ct->tuplehash[!dir].tuple.dst.u3,
689 sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
690 (nat_h245 = rcu_dereference(nat_h245_hook)) &&
691 ct->status & IPS_NAT_MASK) {
692 /* NAT needed */
693 ret = nat_h245(skb, ct, ctinfo, data, dataoff, taddr,
694 port, exp);
695 } else { /* Conntrack only */
696 if (nf_ct_expect_related(exp) == 0) {
697 pr_debug("nf_ct_q931: expect H.245 ");
698 nf_ct_dump_tuple(&exp->tuple);
699 } else
700 ret = -1;
701 }
702
703 nf_ct_expect_put(exp);
704
705 return ret;
706 }
707
708 /* If the calling party is on the same side of the forward-to party,
709 * we don't need to track the second call */
710 static int callforward_do_filter(const union nf_inet_addr *src,
711 const union nf_inet_addr *dst,
712 u_int8_t family)
713 {
714 const struct nf_afinfo *afinfo;
715 int ret = 0;
716
717 /* rcu_read_lock()ed by nf_hook_slow() */
718 afinfo = nf_get_afinfo(family);
719 if (!afinfo)
720 return 0;
721
722 switch (family) {
723 case AF_INET: {
724 struct flowi4 fl1, fl2;
725 struct rtable *rt1, *rt2;
726
727 memset(&fl1, 0, sizeof(fl1));
728 fl1.daddr = src->ip;
729
730 memset(&fl2, 0, sizeof(fl2));
731 fl2.daddr = dst->ip;
732 if (!afinfo->route(&init_net, (struct dst_entry **)&rt1,
733 flowi4_to_flowi(&fl1), false)) {
734 if (!afinfo->route(&init_net, (struct dst_entry **)&rt2,
735 flowi4_to_flowi(&fl2), false)) {
736 if (rt1->rt_gateway == rt2->rt_gateway &&
737 rt1->dst.dev == rt2->dst.dev)
738 ret = 1;
739 dst_release(&rt2->dst);
740 }
741 dst_release(&rt1->dst);
742 }
743 break;
744 }
745 #if IS_ENABLED(CONFIG_NF_CONNTRACK_IPV6)
746 case AF_INET6: {
747 struct flowi6 fl1, fl2;
748 struct rt6_info *rt1, *rt2;
749
750 memset(&fl1, 0, sizeof(fl1));
751 fl1.daddr = src->in6;
752
753 memset(&fl2, 0, sizeof(fl2));
754 fl2.daddr = dst->in6;
755 if (!afinfo->route(&init_net, (struct dst_entry **)&rt1,
756 flowi6_to_flowi(&fl1), false)) {
757 if (!afinfo->route(&init_net, (struct dst_entry **)&rt2,
758 flowi6_to_flowi(&fl2), false)) {
759 if (!memcmp(&rt1->rt6i_gateway, &rt2->rt6i_gateway,
760 sizeof(rt1->rt6i_gateway)) &&
761 rt1->dst.dev == rt2->dst.dev)
762 ret = 1;
763 dst_release(&rt2->dst);
764 }
765 dst_release(&rt1->dst);
766 }
767 break;
768 }
769 #endif
770 }
771 return ret;
772
773 }
774
775 /****************************************************************************/
776 static int expect_callforwarding(struct sk_buff *skb,
777 struct nf_conn *ct,
778 enum ip_conntrack_info ctinfo,
779 unsigned char **data, int dataoff,
780 TransportAddress *taddr)
781 {
782 int dir = CTINFO2DIR(ctinfo);
783 int ret = 0;
784 __be16 port;
785 union nf_inet_addr addr;
786 struct nf_conntrack_expect *exp;
787 typeof(nat_callforwarding_hook) nat_callforwarding;
788
789 /* Read alternativeAddress */
790 if (!get_h225_addr(ct, *data, taddr, &addr, &port) || port == 0)
791 return 0;
792
793 /* If the calling party is on the same side of the forward-to party,
794 * we don't need to track the second call */
795 if (callforward_filter &&
796 callforward_do_filter(&addr, &ct->tuplehash[!dir].tuple.src.u3,
797 nf_ct_l3num(ct))) {
798 pr_debug("nf_ct_q931: Call Forwarding not tracked\n");
799 return 0;
800 }
801
802 /* Create expect for the second call leg */
803 if ((exp = nf_ct_expect_alloc(ct)) == NULL)
804 return -1;
805 nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
806 &ct->tuplehash[!dir].tuple.src.u3, &addr,
807 IPPROTO_TCP, NULL, &port);
808 exp->helper = nf_conntrack_helper_q931;
809
810 if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
811 &ct->tuplehash[!dir].tuple.dst.u3,
812 sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
813 (nat_callforwarding = rcu_dereference(nat_callforwarding_hook)) &&
814 ct->status & IPS_NAT_MASK) {
815 /* Need NAT */
816 ret = nat_callforwarding(skb, ct, ctinfo, data, dataoff,
817 taddr, port, exp);
818 } else { /* Conntrack only */
819 if (nf_ct_expect_related(exp) == 0) {
820 pr_debug("nf_ct_q931: expect Call Forwarding ");
821 nf_ct_dump_tuple(&exp->tuple);
822 } else
823 ret = -1;
824 }
825
826 nf_ct_expect_put(exp);
827
828 return ret;
829 }
830
831 /****************************************************************************/
832 static int process_setup(struct sk_buff *skb, struct nf_conn *ct,
833 enum ip_conntrack_info ctinfo,
834 unsigned char **data, int dataoff,
835 Setup_UUIE *setup)
836 {
837 int dir = CTINFO2DIR(ctinfo);
838 int ret;
839 int i;
840 __be16 port;
841 union nf_inet_addr addr;
842 typeof(set_h225_addr_hook) set_h225_addr;
843
844 pr_debug("nf_ct_q931: Setup\n");
845
846 if (setup->options & eSetup_UUIE_h245Address) {
847 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
848 &setup->h245Address);
849 if (ret < 0)
850 return -1;
851 }
852
853 set_h225_addr = rcu_dereference(set_h225_addr_hook);
854 if ((setup->options & eSetup_UUIE_destCallSignalAddress) &&
855 (set_h225_addr) && ct->status & IPS_NAT_MASK &&
856 get_h225_addr(ct, *data, &setup->destCallSignalAddress,
857 &addr, &port) &&
858 memcmp(&addr, &ct->tuplehash[!dir].tuple.src.u3, sizeof(addr))) {
859 pr_debug("nf_ct_q931: set destCallSignalAddress %pI6:%hu->%pI6:%hu\n",
860 &addr, ntohs(port), &ct->tuplehash[!dir].tuple.src.u3,
861 ntohs(ct->tuplehash[!dir].tuple.src.u.tcp.port));
862 ret = set_h225_addr(skb, data, dataoff,
863 &setup->destCallSignalAddress,
864 &ct->tuplehash[!dir].tuple.src.u3,
865 ct->tuplehash[!dir].tuple.src.u.tcp.port);
866 if (ret < 0)
867 return -1;
868 }
869
870 if ((setup->options & eSetup_UUIE_sourceCallSignalAddress) &&
871 (set_h225_addr) && ct->status & IPS_NAT_MASK &&
872 get_h225_addr(ct, *data, &setup->sourceCallSignalAddress,
873 &addr, &port) &&
874 memcmp(&addr, &ct->tuplehash[!dir].tuple.dst.u3, sizeof(addr))) {
875 pr_debug("nf_ct_q931: set sourceCallSignalAddress %pI6:%hu->%pI6:%hu\n",
876 &addr, ntohs(port), &ct->tuplehash[!dir].tuple.dst.u3,
877 ntohs(ct->tuplehash[!dir].tuple.dst.u.tcp.port));
878 ret = set_h225_addr(skb, data, dataoff,
879 &setup->sourceCallSignalAddress,
880 &ct->tuplehash[!dir].tuple.dst.u3,
881 ct->tuplehash[!dir].tuple.dst.u.tcp.port);
882 if (ret < 0)
883 return -1;
884 }
885
886 if (setup->options & eSetup_UUIE_fastStart) {
887 for (i = 0; i < setup->fastStart.count; i++) {
888 ret = process_olc(skb, ct, ctinfo, data, dataoff,
889 &setup->fastStart.item[i]);
890 if (ret < 0)
891 return -1;
892 }
893 }
894
895 return 0;
896 }
897
898 /****************************************************************************/
899 static int process_callproceeding(struct sk_buff *skb,
900 struct nf_conn *ct,
901 enum ip_conntrack_info ctinfo,
902 unsigned char **data, int dataoff,
903 CallProceeding_UUIE *callproc)
904 {
905 int ret;
906 int i;
907
908 pr_debug("nf_ct_q931: CallProceeding\n");
909
910 if (callproc->options & eCallProceeding_UUIE_h245Address) {
911 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
912 &callproc->h245Address);
913 if (ret < 0)
914 return -1;
915 }
916
917 if (callproc->options & eCallProceeding_UUIE_fastStart) {
918 for (i = 0; i < callproc->fastStart.count; i++) {
919 ret = process_olc(skb, ct, ctinfo, data, dataoff,
920 &callproc->fastStart.item[i]);
921 if (ret < 0)
922 return -1;
923 }
924 }
925
926 return 0;
927 }
928
929 /****************************************************************************/
930 static int process_connect(struct sk_buff *skb, struct nf_conn *ct,
931 enum ip_conntrack_info ctinfo,
932 unsigned char **data, int dataoff,
933 Connect_UUIE *connect)
934 {
935 int ret;
936 int i;
937
938 pr_debug("nf_ct_q931: Connect\n");
939
940 if (connect->options & eConnect_UUIE_h245Address) {
941 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
942 &connect->h245Address);
943 if (ret < 0)
944 return -1;
945 }
946
947 if (connect->options & eConnect_UUIE_fastStart) {
948 for (i = 0; i < connect->fastStart.count; i++) {
949 ret = process_olc(skb, ct, ctinfo, data, dataoff,
950 &connect->fastStart.item[i]);
951 if (ret < 0)
952 return -1;
953 }
954 }
955
956 return 0;
957 }
958
959 /****************************************************************************/
960 static int process_alerting(struct sk_buff *skb, struct nf_conn *ct,
961 enum ip_conntrack_info ctinfo,
962 unsigned char **data, int dataoff,
963 Alerting_UUIE *alert)
964 {
965 int ret;
966 int i;
967
968 pr_debug("nf_ct_q931: Alerting\n");
969
970 if (alert->options & eAlerting_UUIE_h245Address) {
971 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
972 &alert->h245Address);
973 if (ret < 0)
974 return -1;
975 }
976
977 if (alert->options & eAlerting_UUIE_fastStart) {
978 for (i = 0; i < alert->fastStart.count; i++) {
979 ret = process_olc(skb, ct, ctinfo, data, dataoff,
980 &alert->fastStart.item[i]);
981 if (ret < 0)
982 return -1;
983 }
984 }
985
986 return 0;
987 }
988
989 /****************************************************************************/
990 static int process_facility(struct sk_buff *skb, struct nf_conn *ct,
991 enum ip_conntrack_info ctinfo,
992 unsigned char **data, int dataoff,
993 Facility_UUIE *facility)
994 {
995 int ret;
996 int i;
997
998 pr_debug("nf_ct_q931: Facility\n");
999
1000 if (facility->reason.choice == eFacilityReason_callForwarded) {
1001 if (facility->options & eFacility_UUIE_alternativeAddress)
1002 return expect_callforwarding(skb, ct, ctinfo, data,
1003 dataoff,
1004 &facility->
1005 alternativeAddress);
1006 return 0;
1007 }
1008
1009 if (facility->options & eFacility_UUIE_h245Address) {
1010 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
1011 &facility->h245Address);
1012 if (ret < 0)
1013 return -1;
1014 }
1015
1016 if (facility->options & eFacility_UUIE_fastStart) {
1017 for (i = 0; i < facility->fastStart.count; i++) {
1018 ret = process_olc(skb, ct, ctinfo, data, dataoff,
1019 &facility->fastStart.item[i]);
1020 if (ret < 0)
1021 return -1;
1022 }
1023 }
1024
1025 return 0;
1026 }
1027
1028 /****************************************************************************/
1029 static int process_progress(struct sk_buff *skb, struct nf_conn *ct,
1030 enum ip_conntrack_info ctinfo,
1031 unsigned char **data, int dataoff,
1032 Progress_UUIE *progress)
1033 {
1034 int ret;
1035 int i;
1036
1037 pr_debug("nf_ct_q931: Progress\n");
1038
1039 if (progress->options & eProgress_UUIE_h245Address) {
1040 ret = expect_h245(skb, ct, ctinfo, data, dataoff,
1041 &progress->h245Address);
1042 if (ret < 0)
1043 return -1;
1044 }
1045
1046 if (progress->options & eProgress_UUIE_fastStart) {
1047 for (i = 0; i < progress->fastStart.count; i++) {
1048 ret = process_olc(skb, ct, ctinfo, data, dataoff,
1049 &progress->fastStart.item[i]);
1050 if (ret < 0)
1051 return -1;
1052 }
1053 }
1054
1055 return 0;
1056 }
1057
1058 /****************************************************************************/
1059 static int process_q931(struct sk_buff *skb, struct nf_conn *ct,
1060 enum ip_conntrack_info ctinfo,
1061 unsigned char **data, int dataoff, Q931 *q931)
1062 {
1063 H323_UU_PDU *pdu = &q931->UUIE.h323_uu_pdu;
1064 int i;
1065 int ret = 0;
1066
1067 switch (pdu->h323_message_body.choice) {
1068 case eH323_UU_PDU_h323_message_body_setup:
1069 ret = process_setup(skb, ct, ctinfo, data, dataoff,
1070 &pdu->h323_message_body.setup);
1071 break;
1072 case eH323_UU_PDU_h323_message_body_callProceeding:
1073 ret = process_callproceeding(skb, ct, ctinfo, data, dataoff,
1074 &pdu->h323_message_body.
1075 callProceeding);
1076 break;
1077 case eH323_UU_PDU_h323_message_body_connect:
1078 ret = process_connect(skb, ct, ctinfo, data, dataoff,
1079 &pdu->h323_message_body.connect);
1080 break;
1081 case eH323_UU_PDU_h323_message_body_alerting:
1082 ret = process_alerting(skb, ct, ctinfo, data, dataoff,
1083 &pdu->h323_message_body.alerting);
1084 break;
1085 case eH323_UU_PDU_h323_message_body_facility:
1086 ret = process_facility(skb, ct, ctinfo, data, dataoff,
1087 &pdu->h323_message_body.facility);
1088 break;
1089 case eH323_UU_PDU_h323_message_body_progress:
1090 ret = process_progress(skb, ct, ctinfo, data, dataoff,
1091 &pdu->h323_message_body.progress);
1092 break;
1093 default:
1094 pr_debug("nf_ct_q931: Q.931 signal %d\n",
1095 pdu->h323_message_body.choice);
1096 break;
1097 }
1098
1099 if (ret < 0)
1100 return -1;
1101
1102 if (pdu->options & eH323_UU_PDU_h245Control) {
1103 for (i = 0; i < pdu->h245Control.count; i++) {
1104 ret = process_h245(skb, ct, ctinfo, data, dataoff,
1105 &pdu->h245Control.item[i]);
1106 if (ret < 0)
1107 return -1;
1108 }
1109 }
1110
1111 return 0;
1112 }
1113
1114 /****************************************************************************/
1115 static int q931_help(struct sk_buff *skb, unsigned int protoff,
1116 struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1117 {
1118 static Q931 q931;
1119 unsigned char *data = NULL;
1120 int datalen;
1121 int dataoff;
1122 int ret;
1123
1124 /* Until there's been traffic both ways, don't look in packets. */
1125 if (ctinfo != IP_CT_ESTABLISHED && ctinfo != IP_CT_ESTABLISHED_REPLY)
1126 return NF_ACCEPT;
1127
1128 pr_debug("nf_ct_q931: skblen = %u\n", skb->len);
1129
1130 spin_lock_bh(&nf_h323_lock);
1131
1132 /* Process each TPKT */
1133 while (get_tpkt_data(skb, protoff, ct, ctinfo,
1134 &data, &datalen, &dataoff)) {
1135 pr_debug("nf_ct_q931: TPKT len=%d ", datalen);
1136 nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1137
1138 /* Decode Q.931 signal */
1139 ret = DecodeQ931(data, datalen, &q931);
1140 if (ret < 0) {
1141 pr_debug("nf_ct_q931: decoding error: %s\n",
1142 ret == H323_ERROR_BOUND ?
1143 "out of bound" : "out of range");
1144 /* We don't drop when decoding error */
1145 break;
1146 }
1147
1148 /* Process Q.931 signal */
1149 if (process_q931(skb, ct, ctinfo, &data, dataoff, &q931) < 0)
1150 goto drop;
1151 }
1152
1153 spin_unlock_bh(&nf_h323_lock);
1154 return NF_ACCEPT;
1155
1156 drop:
1157 spin_unlock_bh(&nf_h323_lock);
1158 net_info_ratelimited("nf_ct_q931: packet dropped\n");
1159 return NF_DROP;
1160 }
1161
1162 /****************************************************************************/
1163 static const struct nf_conntrack_expect_policy q931_exp_policy = {
1164 /* T.120 and H.245 */
1165 .max_expected = H323_RTP_CHANNEL_MAX * 4 + 4,
1166 .timeout = 240,
1167 };
1168
1169 static struct nf_conntrack_helper nf_conntrack_helper_q931[] __read_mostly = {
1170 {
1171 .name = "Q.931",
1172 .me = THIS_MODULE,
1173 .tuple.src.l3num = AF_INET,
1174 .tuple.src.u.tcp.port = cpu_to_be16(Q931_PORT),
1175 .tuple.dst.protonum = IPPROTO_TCP,
1176 .help = q931_help,
1177 .expect_policy = &q931_exp_policy,
1178 },
1179 {
1180 .name = "Q.931",
1181 .me = THIS_MODULE,
1182 .tuple.src.l3num = AF_INET6,
1183 .tuple.src.u.tcp.port = cpu_to_be16(Q931_PORT),
1184 .tuple.dst.protonum = IPPROTO_TCP,
1185 .help = q931_help,
1186 .expect_policy = &q931_exp_policy,
1187 },
1188 };
1189
1190 /****************************************************************************/
1191 static unsigned char *get_udp_data(struct sk_buff *skb, unsigned int protoff,
1192 int *datalen)
1193 {
1194 const struct udphdr *uh;
1195 struct udphdr _uh;
1196 int dataoff;
1197
1198 uh = skb_header_pointer(skb, protoff, sizeof(_uh), &_uh);
1199 if (uh == NULL)
1200 return NULL;
1201 dataoff = protoff + sizeof(_uh);
1202 if (dataoff >= skb->len)
1203 return NULL;
1204 *datalen = skb->len - dataoff;
1205 return skb_header_pointer(skb, dataoff, *datalen, h323_buffer);
1206 }
1207
1208 /****************************************************************************/
1209 static struct nf_conntrack_expect *find_expect(struct nf_conn *ct,
1210 union nf_inet_addr *addr,
1211 __be16 port)
1212 {
1213 struct net *net = nf_ct_net(ct);
1214 struct nf_conntrack_expect *exp;
1215 struct nf_conntrack_tuple tuple;
1216
1217 memset(&tuple.src.u3, 0, sizeof(tuple.src.u3));
1218 tuple.src.u.tcp.port = 0;
1219 memcpy(&tuple.dst.u3, addr, sizeof(tuple.dst.u3));
1220 tuple.dst.u.tcp.port = port;
1221 tuple.dst.protonum = IPPROTO_TCP;
1222
1223 exp = __nf_ct_expect_find(net, nf_ct_zone(ct), &tuple);
1224 if (exp && exp->master == ct)
1225 return exp;
1226 return NULL;
1227 }
1228
1229 /****************************************************************************/
1230 static int set_expect_timeout(struct nf_conntrack_expect *exp,
1231 unsigned int timeout)
1232 {
1233 if (!exp || !del_timer(&exp->timeout))
1234 return 0;
1235
1236 exp->timeout.expires = jiffies + timeout * HZ;
1237 add_timer(&exp->timeout);
1238
1239 return 1;
1240 }
1241
1242 /****************************************************************************/
1243 static int expect_q931(struct sk_buff *skb, struct nf_conn *ct,
1244 enum ip_conntrack_info ctinfo,
1245 unsigned char **data,
1246 TransportAddress *taddr, int count)
1247 {
1248 struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1249 int dir = CTINFO2DIR(ctinfo);
1250 int ret = 0;
1251 int i;
1252 __be16 port;
1253 union nf_inet_addr addr;
1254 struct nf_conntrack_expect *exp;
1255 typeof(nat_q931_hook) nat_q931;
1256
1257 /* Look for the first related address */
1258 for (i = 0; i < count; i++) {
1259 if (get_h225_addr(ct, *data, &taddr[i], &addr, &port) &&
1260 memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3,
1261 sizeof(addr)) == 0 && port != 0)
1262 break;
1263 }
1264
1265 if (i >= count) /* Not found */
1266 return 0;
1267
1268 /* Create expect for Q.931 */
1269 if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1270 return -1;
1271 nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1272 gkrouted_only ? /* only accept calls from GK? */
1273 &ct->tuplehash[!dir].tuple.src.u3 : NULL,
1274 &ct->tuplehash[!dir].tuple.dst.u3,
1275 IPPROTO_TCP, NULL, &port);
1276 exp->helper = nf_conntrack_helper_q931;
1277 exp->flags = NF_CT_EXPECT_PERMANENT; /* Accept multiple calls */
1278
1279 nat_q931 = rcu_dereference(nat_q931_hook);
1280 if (nat_q931 && ct->status & IPS_NAT_MASK) { /* Need NAT */
1281 ret = nat_q931(skb, ct, ctinfo, data, taddr, i, port, exp);
1282 } else { /* Conntrack only */
1283 if (nf_ct_expect_related(exp) == 0) {
1284 pr_debug("nf_ct_ras: expect Q.931 ");
1285 nf_ct_dump_tuple(&exp->tuple);
1286
1287 /* Save port for looking up expect in processing RCF */
1288 info->sig_port[dir] = port;
1289 } else
1290 ret = -1;
1291 }
1292
1293 nf_ct_expect_put(exp);
1294
1295 return ret;
1296 }
1297
1298 /****************************************************************************/
1299 static int process_grq(struct sk_buff *skb, struct nf_conn *ct,
1300 enum ip_conntrack_info ctinfo,
1301 unsigned char **data, GatekeeperRequest *grq)
1302 {
1303 typeof(set_ras_addr_hook) set_ras_addr;
1304
1305 pr_debug("nf_ct_ras: GRQ\n");
1306
1307 set_ras_addr = rcu_dereference(set_ras_addr_hook);
1308 if (set_ras_addr && ct->status & IPS_NAT_MASK) /* NATed */
1309 return set_ras_addr(skb, ct, ctinfo, data,
1310 &grq->rasAddress, 1);
1311 return 0;
1312 }
1313
1314 /****************************************************************************/
1315 static int process_gcf(struct sk_buff *skb, struct nf_conn *ct,
1316 enum ip_conntrack_info ctinfo,
1317 unsigned char **data, GatekeeperConfirm *gcf)
1318 {
1319 int dir = CTINFO2DIR(ctinfo);
1320 int ret = 0;
1321 __be16 port;
1322 union nf_inet_addr addr;
1323 struct nf_conntrack_expect *exp;
1324
1325 pr_debug("nf_ct_ras: GCF\n");
1326
1327 if (!get_h225_addr(ct, *data, &gcf->rasAddress, &addr, &port))
1328 return 0;
1329
1330 /* Registration port is the same as discovery port */
1331 if (!memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1332 port == ct->tuplehash[dir].tuple.src.u.udp.port)
1333 return 0;
1334
1335 /* Avoid RAS expectation loops. A GCF is never expected. */
1336 if (test_bit(IPS_EXPECTED_BIT, &ct->status))
1337 return 0;
1338
1339 /* Need new expect */
1340 if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1341 return -1;
1342 nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1343 &ct->tuplehash[!dir].tuple.src.u3, &addr,
1344 IPPROTO_UDP, NULL, &port);
1345 exp->helper = nf_conntrack_helper_ras;
1346
1347 if (nf_ct_expect_related(exp) == 0) {
1348 pr_debug("nf_ct_ras: expect RAS ");
1349 nf_ct_dump_tuple(&exp->tuple);
1350 } else
1351 ret = -1;
1352
1353 nf_ct_expect_put(exp);
1354
1355 return ret;
1356 }
1357
1358 /****************************************************************************/
1359 static int process_rrq(struct sk_buff *skb, struct nf_conn *ct,
1360 enum ip_conntrack_info ctinfo,
1361 unsigned char **data, RegistrationRequest *rrq)
1362 {
1363 struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1364 int ret;
1365 typeof(set_ras_addr_hook) set_ras_addr;
1366
1367 pr_debug("nf_ct_ras: RRQ\n");
1368
1369 ret = expect_q931(skb, ct, ctinfo, data,
1370 rrq->callSignalAddress.item,
1371 rrq->callSignalAddress.count);
1372 if (ret < 0)
1373 return -1;
1374
1375 set_ras_addr = rcu_dereference(set_ras_addr_hook);
1376 if (set_ras_addr && ct->status & IPS_NAT_MASK) {
1377 ret = set_ras_addr(skb, ct, ctinfo, data,
1378 rrq->rasAddress.item,
1379 rrq->rasAddress.count);
1380 if (ret < 0)
1381 return -1;
1382 }
1383
1384 if (rrq->options & eRegistrationRequest_timeToLive) {
1385 pr_debug("nf_ct_ras: RRQ TTL = %u seconds\n", rrq->timeToLive);
1386 info->timeout = rrq->timeToLive;
1387 } else
1388 info->timeout = default_rrq_ttl;
1389
1390 return 0;
1391 }
1392
1393 /****************************************************************************/
1394 static int process_rcf(struct sk_buff *skb, struct nf_conn *ct,
1395 enum ip_conntrack_info ctinfo,
1396 unsigned char **data, RegistrationConfirm *rcf)
1397 {
1398 struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1399 int dir = CTINFO2DIR(ctinfo);
1400 int ret;
1401 struct nf_conntrack_expect *exp;
1402 typeof(set_sig_addr_hook) set_sig_addr;
1403
1404 pr_debug("nf_ct_ras: RCF\n");
1405
1406 set_sig_addr = rcu_dereference(set_sig_addr_hook);
1407 if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1408 ret = set_sig_addr(skb, ct, ctinfo, data,
1409 rcf->callSignalAddress.item,
1410 rcf->callSignalAddress.count);
1411 if (ret < 0)
1412 return -1;
1413 }
1414
1415 if (rcf->options & eRegistrationConfirm_timeToLive) {
1416 pr_debug("nf_ct_ras: RCF TTL = %u seconds\n", rcf->timeToLive);
1417 info->timeout = rcf->timeToLive;
1418 }
1419
1420 if (info->timeout > 0) {
1421 pr_debug("nf_ct_ras: set RAS connection timeout to "
1422 "%u seconds\n", info->timeout);
1423 nf_ct_refresh(ct, skb, info->timeout * HZ);
1424
1425 /* Set expect timeout */
1426 spin_lock_bh(&nf_conntrack_lock);
1427 exp = find_expect(ct, &ct->tuplehash[dir].tuple.dst.u3,
1428 info->sig_port[!dir]);
1429 if (exp) {
1430 pr_debug("nf_ct_ras: set Q.931 expect "
1431 "timeout to %u seconds for",
1432 info->timeout);
1433 nf_ct_dump_tuple(&exp->tuple);
1434 set_expect_timeout(exp, info->timeout);
1435 }
1436 spin_unlock_bh(&nf_conntrack_lock);
1437 }
1438
1439 return 0;
1440 }
1441
1442 /****************************************************************************/
1443 static int process_urq(struct sk_buff *skb, struct nf_conn *ct,
1444 enum ip_conntrack_info ctinfo,
1445 unsigned char **data, UnregistrationRequest *urq)
1446 {
1447 struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1448 int dir = CTINFO2DIR(ctinfo);
1449 int ret;
1450 typeof(set_sig_addr_hook) set_sig_addr;
1451
1452 pr_debug("nf_ct_ras: URQ\n");
1453
1454 set_sig_addr = rcu_dereference(set_sig_addr_hook);
1455 if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1456 ret = set_sig_addr(skb, ct, ctinfo, data,
1457 urq->callSignalAddress.item,
1458 urq->callSignalAddress.count);
1459 if (ret < 0)
1460 return -1;
1461 }
1462
1463 /* Clear old expect */
1464 nf_ct_remove_expectations(ct);
1465 info->sig_port[dir] = 0;
1466 info->sig_port[!dir] = 0;
1467
1468 /* Give it 30 seconds for UCF or URJ */
1469 nf_ct_refresh(ct, skb, 30 * HZ);
1470
1471 return 0;
1472 }
1473
1474 /****************************************************************************/
1475 static int process_arq(struct sk_buff *skb, struct nf_conn *ct,
1476 enum ip_conntrack_info ctinfo,
1477 unsigned char **data, AdmissionRequest *arq)
1478 {
1479 const struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
1480 int dir = CTINFO2DIR(ctinfo);
1481 __be16 port;
1482 union nf_inet_addr addr;
1483 typeof(set_h225_addr_hook) set_h225_addr;
1484
1485 pr_debug("nf_ct_ras: ARQ\n");
1486
1487 set_h225_addr = rcu_dereference(set_h225_addr_hook);
1488 if ((arq->options & eAdmissionRequest_destCallSignalAddress) &&
1489 get_h225_addr(ct, *data, &arq->destCallSignalAddress,
1490 &addr, &port) &&
1491 !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1492 port == info->sig_port[dir] &&
1493 set_h225_addr && ct->status & IPS_NAT_MASK) {
1494 /* Answering ARQ */
1495 return set_h225_addr(skb, data, 0,
1496 &arq->destCallSignalAddress,
1497 &ct->tuplehash[!dir].tuple.dst.u3,
1498 info->sig_port[!dir]);
1499 }
1500
1501 if ((arq->options & eAdmissionRequest_srcCallSignalAddress) &&
1502 get_h225_addr(ct, *data, &arq->srcCallSignalAddress,
1503 &addr, &port) &&
1504 !memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
1505 set_h225_addr && ct->status & IPS_NAT_MASK) {
1506 /* Calling ARQ */
1507 return set_h225_addr(skb, data, 0,
1508 &arq->srcCallSignalAddress,
1509 &ct->tuplehash[!dir].tuple.dst.u3,
1510 port);
1511 }
1512
1513 return 0;
1514 }
1515
1516 /****************************************************************************/
1517 static int process_acf(struct sk_buff *skb, struct nf_conn *ct,
1518 enum ip_conntrack_info ctinfo,
1519 unsigned char **data, AdmissionConfirm *acf)
1520 {
1521 int dir = CTINFO2DIR(ctinfo);
1522 int ret = 0;
1523 __be16 port;
1524 union nf_inet_addr addr;
1525 struct nf_conntrack_expect *exp;
1526 typeof(set_sig_addr_hook) set_sig_addr;
1527
1528 pr_debug("nf_ct_ras: ACF\n");
1529
1530 if (!get_h225_addr(ct, *data, &acf->destCallSignalAddress,
1531 &addr, &port))
1532 return 0;
1533
1534 if (!memcmp(&addr, &ct->tuplehash[dir].tuple.dst.u3, sizeof(addr))) {
1535 /* Answering ACF */
1536 set_sig_addr = rcu_dereference(set_sig_addr_hook);
1537 if (set_sig_addr && ct->status & IPS_NAT_MASK)
1538 return set_sig_addr(skb, ct, ctinfo, data,
1539 &acf->destCallSignalAddress, 1);
1540 return 0;
1541 }
1542
1543 /* Need new expect */
1544 if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1545 return -1;
1546 nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1547 &ct->tuplehash[!dir].tuple.src.u3, &addr,
1548 IPPROTO_TCP, NULL, &port);
1549 exp->flags = NF_CT_EXPECT_PERMANENT;
1550 exp->helper = nf_conntrack_helper_q931;
1551
1552 if (nf_ct_expect_related(exp) == 0) {
1553 pr_debug("nf_ct_ras: expect Q.931 ");
1554 nf_ct_dump_tuple(&exp->tuple);
1555 } else
1556 ret = -1;
1557
1558 nf_ct_expect_put(exp);
1559
1560 return ret;
1561 }
1562
1563 /****************************************************************************/
1564 static int process_lrq(struct sk_buff *skb, struct nf_conn *ct,
1565 enum ip_conntrack_info ctinfo,
1566 unsigned char **data, LocationRequest *lrq)
1567 {
1568 typeof(set_ras_addr_hook) set_ras_addr;
1569
1570 pr_debug("nf_ct_ras: LRQ\n");
1571
1572 set_ras_addr = rcu_dereference(set_ras_addr_hook);
1573 if (set_ras_addr && ct->status & IPS_NAT_MASK)
1574 return set_ras_addr(skb, ct, ctinfo, data,
1575 &lrq->replyAddress, 1);
1576 return 0;
1577 }
1578
1579 /****************************************************************************/
1580 static int process_lcf(struct sk_buff *skb, struct nf_conn *ct,
1581 enum ip_conntrack_info ctinfo,
1582 unsigned char **data, LocationConfirm *lcf)
1583 {
1584 int dir = CTINFO2DIR(ctinfo);
1585 int ret = 0;
1586 __be16 port;
1587 union nf_inet_addr addr;
1588 struct nf_conntrack_expect *exp;
1589
1590 pr_debug("nf_ct_ras: LCF\n");
1591
1592 if (!get_h225_addr(ct, *data, &lcf->callSignalAddress,
1593 &addr, &port))
1594 return 0;
1595
1596 /* Need new expect for call signal */
1597 if ((exp = nf_ct_expect_alloc(ct)) == NULL)
1598 return -1;
1599 nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
1600 &ct->tuplehash[!dir].tuple.src.u3, &addr,
1601 IPPROTO_TCP, NULL, &port);
1602 exp->flags = NF_CT_EXPECT_PERMANENT;
1603 exp->helper = nf_conntrack_helper_q931;
1604
1605 if (nf_ct_expect_related(exp) == 0) {
1606 pr_debug("nf_ct_ras: expect Q.931 ");
1607 nf_ct_dump_tuple(&exp->tuple);
1608 } else
1609 ret = -1;
1610
1611 nf_ct_expect_put(exp);
1612
1613 /* Ignore rasAddress */
1614
1615 return ret;
1616 }
1617
1618 /****************************************************************************/
1619 static int process_irr(struct sk_buff *skb, struct nf_conn *ct,
1620 enum ip_conntrack_info ctinfo,
1621 unsigned char **data, InfoRequestResponse *irr)
1622 {
1623 int ret;
1624 typeof(set_ras_addr_hook) set_ras_addr;
1625 typeof(set_sig_addr_hook) set_sig_addr;
1626
1627 pr_debug("nf_ct_ras: IRR\n");
1628
1629 set_ras_addr = rcu_dereference(set_ras_addr_hook);
1630 if (set_ras_addr && ct->status & IPS_NAT_MASK) {
1631 ret = set_ras_addr(skb, ct, ctinfo, data,
1632 &irr->rasAddress, 1);
1633 if (ret < 0)
1634 return -1;
1635 }
1636
1637 set_sig_addr = rcu_dereference(set_sig_addr_hook);
1638 if (set_sig_addr && ct->status & IPS_NAT_MASK) {
1639 ret = set_sig_addr(skb, ct, ctinfo, data,
1640 irr->callSignalAddress.item,
1641 irr->callSignalAddress.count);
1642 if (ret < 0)
1643 return -1;
1644 }
1645
1646 return 0;
1647 }
1648
1649 /****************************************************************************/
1650 static int process_ras(struct sk_buff *skb, struct nf_conn *ct,
1651 enum ip_conntrack_info ctinfo,
1652 unsigned char **data, RasMessage *ras)
1653 {
1654 switch (ras->choice) {
1655 case eRasMessage_gatekeeperRequest:
1656 return process_grq(skb, ct, ctinfo, data,
1657 &ras->gatekeeperRequest);
1658 case eRasMessage_gatekeeperConfirm:
1659 return process_gcf(skb, ct, ctinfo, data,
1660 &ras->gatekeeperConfirm);
1661 case eRasMessage_registrationRequest:
1662 return process_rrq(skb, ct, ctinfo, data,
1663 &ras->registrationRequest);
1664 case eRasMessage_registrationConfirm:
1665 return process_rcf(skb, ct, ctinfo, data,
1666 &ras->registrationConfirm);
1667 case eRasMessage_unregistrationRequest:
1668 return process_urq(skb, ct, ctinfo, data,
1669 &ras->unregistrationRequest);
1670 case eRasMessage_admissionRequest:
1671 return process_arq(skb, ct, ctinfo, data,
1672 &ras->admissionRequest);
1673 case eRasMessage_admissionConfirm:
1674 return process_acf(skb, ct, ctinfo, data,
1675 &ras->admissionConfirm);
1676 case eRasMessage_locationRequest:
1677 return process_lrq(skb, ct, ctinfo, data,
1678 &ras->locationRequest);
1679 case eRasMessage_locationConfirm:
1680 return process_lcf(skb, ct, ctinfo, data,
1681 &ras->locationConfirm);
1682 case eRasMessage_infoRequestResponse:
1683 return process_irr(skb, ct, ctinfo, data,
1684 &ras->infoRequestResponse);
1685 default:
1686 pr_debug("nf_ct_ras: RAS message %d\n", ras->choice);
1687 break;
1688 }
1689
1690 return 0;
1691 }
1692
1693 /****************************************************************************/
1694 static int ras_help(struct sk_buff *skb, unsigned int protoff,
1695 struct nf_conn *ct, enum ip_conntrack_info ctinfo)
1696 {
1697 static RasMessage ras;
1698 unsigned char *data;
1699 int datalen = 0;
1700 int ret;
1701
1702 pr_debug("nf_ct_ras: skblen = %u\n", skb->len);
1703
1704 spin_lock_bh(&nf_h323_lock);
1705
1706 /* Get UDP data */
1707 data = get_udp_data(skb, protoff, &datalen);
1708 if (data == NULL)
1709 goto accept;
1710 pr_debug("nf_ct_ras: RAS message len=%d ", datalen);
1711 nf_ct_dump_tuple(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
1712
1713 /* Decode RAS message */
1714 ret = DecodeRasMessage(data, datalen, &ras);
1715 if (ret < 0) {
1716 pr_debug("nf_ct_ras: decoding error: %s\n",
1717 ret == H323_ERROR_BOUND ?
1718 "out of bound" : "out of range");
1719 goto accept;
1720 }
1721
1722 /* Process RAS message */
1723 if (process_ras(skb, ct, ctinfo, &data, &ras) < 0)
1724 goto drop;
1725
1726 accept:
1727 spin_unlock_bh(&nf_h323_lock);
1728 return NF_ACCEPT;
1729
1730 drop:
1731 spin_unlock_bh(&nf_h323_lock);
1732 net_info_ratelimited("nf_ct_ras: packet dropped\n");
1733 return NF_DROP;
1734 }
1735
1736 /****************************************************************************/
1737 static const struct nf_conntrack_expect_policy ras_exp_policy = {
1738 .max_expected = 32,
1739 .timeout = 240,
1740 };
1741
1742 static struct nf_conntrack_helper nf_conntrack_helper_ras[] __read_mostly = {
1743 {
1744 .name = "RAS",
1745 .me = THIS_MODULE,
1746 .tuple.src.l3num = AF_INET,
1747 .tuple.src.u.udp.port = cpu_to_be16(RAS_PORT),
1748 .tuple.dst.protonum = IPPROTO_UDP,
1749 .help = ras_help,
1750 .expect_policy = &ras_exp_policy,
1751 },
1752 {
1753 .name = "RAS",
1754 .me = THIS_MODULE,
1755 .tuple.src.l3num = AF_INET6,
1756 .tuple.src.u.udp.port = cpu_to_be16(RAS_PORT),
1757 .tuple.dst.protonum = IPPROTO_UDP,
1758 .help = ras_help,
1759 .expect_policy = &ras_exp_policy,
1760 },
1761 };
1762
1763 /****************************************************************************/
1764 static void __exit nf_conntrack_h323_fini(void)
1765 {
1766 nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[1]);
1767 nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1768 nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1769 nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1770 nf_conntrack_helper_unregister(&nf_conntrack_helper_h245);
1771 kfree(h323_buffer);
1772 pr_debug("nf_ct_h323: fini\n");
1773 }
1774
1775 /****************************************************************************/
1776 static int __init nf_conntrack_h323_init(void)
1777 {
1778 int ret;
1779
1780 h323_buffer = kmalloc(65536, GFP_KERNEL);
1781 if (!h323_buffer)
1782 return -ENOMEM;
1783 ret = nf_conntrack_helper_register(&nf_conntrack_helper_h245);
1784 if (ret < 0)
1785 goto err1;
1786 ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[0]);
1787 if (ret < 0)
1788 goto err2;
1789 ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[1]);
1790 if (ret < 0)
1791 goto err3;
1792 ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[0]);
1793 if (ret < 0)
1794 goto err4;
1795 ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[1]);
1796 if (ret < 0)
1797 goto err5;
1798 pr_debug("nf_ct_h323: init success\n");
1799 return 0;
1800
1801 err5:
1802 nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
1803 err4:
1804 nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
1805 err3:
1806 nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
1807 err2:
1808 nf_conntrack_helper_unregister(&nf_conntrack_helper_h245);
1809 err1:
1810 kfree(h323_buffer);
1811 return ret;
1812 }
1813
1814 /****************************************************************************/
1815 module_init(nf_conntrack_h323_init);
1816 module_exit(nf_conntrack_h323_fini);
1817
1818 EXPORT_SYMBOL_GPL(get_h225_addr);
1819 EXPORT_SYMBOL_GPL(set_h245_addr_hook);
1820 EXPORT_SYMBOL_GPL(set_h225_addr_hook);
1821 EXPORT_SYMBOL_GPL(set_sig_addr_hook);
1822 EXPORT_SYMBOL_GPL(set_ras_addr_hook);
1823 EXPORT_SYMBOL_GPL(nat_rtp_rtcp_hook);
1824 EXPORT_SYMBOL_GPL(nat_t120_hook);
1825 EXPORT_SYMBOL_GPL(nat_h245_hook);
1826 EXPORT_SYMBOL_GPL(nat_callforwarding_hook);
1827 EXPORT_SYMBOL_GPL(nat_q931_hook);
1828
1829 MODULE_AUTHOR("Jing Min Zhao <zhaojingmin@users.sourceforge.net>");
1830 MODULE_DESCRIPTION("H.323 connection tracking helper");
1831 MODULE_LICENSE("GPL");
1832 MODULE_ALIAS("ip_conntrack_h323");
1833 MODULE_ALIAS_NFCT_HELPER("RAS");
1834 MODULE_ALIAS_NFCT_HELPER("Q.931");
1835 MODULE_ALIAS_NFCT_HELPER("H.245");
Linux kernel - Deliverables
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