1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * H.323 connection tracking helper |
4 | * |
5 | * Copyright (c) 2006 Jing Min Zhao <zhaojingmin@users.sourceforge.net> |
6 | * Copyright (c) 2006-2012 Patrick McHardy <kaber@trash.net> |
7 | * |
8 | * Based on the 'brute force' H.323 connection tracking module by |
9 | * Jozsef Kadlecsik <kadlec@netfilter.org> |
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 | #include <linux/netfilter_ipv6.h> |
27 | |
28 | #include <net/netfilter/nf_conntrack.h> |
29 | #include <net/netfilter/nf_conntrack_core.h> |
30 | #include <net/netfilter/nf_conntrack_tuple.h> |
31 | #include <net/netfilter/nf_conntrack_expect.h> |
32 | #include <net/netfilter/nf_conntrack_ecache.h> |
33 | #include <net/netfilter/nf_conntrack_helper.h> |
34 | #include <net/netfilter/nf_conntrack_zones.h> |
35 | #include <linux/netfilter/nf_conntrack_h323.h> |
36 | |
37 | #define H323_MAX_SIZE 65535 |
38 | |
39 | /* Parameters */ |
40 | static unsigned int default_rrq_ttl __read_mostly = 300; |
41 | module_param(default_rrq_ttl, uint, 0600); |
42 | MODULE_PARM_DESC(default_rrq_ttl, "use this TTL if it's missing in RRQ" ); |
43 | |
44 | static int gkrouted_only __read_mostly = 1; |
45 | module_param(gkrouted_only, int, 0600); |
46 | MODULE_PARM_DESC(gkrouted_only, "only accept calls from gatekeeper" ); |
47 | |
48 | static bool callforward_filter __read_mostly = true; |
49 | module_param(callforward_filter, bool, 0600); |
50 | MODULE_PARM_DESC(callforward_filter, "only create call forwarding expectations " |
51 | "if both endpoints are on different sides " |
52 | "(determined by routing information)" ); |
53 | |
54 | const struct nfct_h323_nat_hooks __rcu *nfct_h323_nat_hook __read_mostly; |
55 | EXPORT_SYMBOL_GPL(nfct_h323_nat_hook); |
56 | |
57 | static DEFINE_SPINLOCK(nf_h323_lock); |
58 | static char *h323_buffer; |
59 | |
60 | static struct nf_conntrack_helper nf_conntrack_helper_h245; |
61 | static struct nf_conntrack_helper nf_conntrack_helper_q931[]; |
62 | static struct nf_conntrack_helper nf_conntrack_helper_ras[]; |
63 | |
64 | static int get_tpkt_data(struct sk_buff *skb, unsigned int protoff, |
65 | struct nf_conn *ct, enum ip_conntrack_info ctinfo, |
66 | unsigned char **data, int *datalen, int *dataoff) |
67 | { |
68 | struct nf_ct_h323_master *info = nfct_help_data(ct); |
69 | int dir = CTINFO2DIR(ctinfo); |
70 | const struct tcphdr *th; |
71 | struct tcphdr _tcph; |
72 | int tcpdatalen; |
73 | int tcpdataoff; |
74 | unsigned char *tpkt; |
75 | int tpktlen; |
76 | int tpktoff; |
77 | |
78 | /* Get TCP header */ |
79 | th = skb_header_pointer(skb, offset: protoff, len: sizeof(_tcph), buffer: &_tcph); |
80 | if (th == NULL) |
81 | return 0; |
82 | |
83 | /* Get TCP data offset */ |
84 | tcpdataoff = protoff + th->doff * 4; |
85 | |
86 | /* Get TCP data length */ |
87 | tcpdatalen = skb->len - tcpdataoff; |
88 | if (tcpdatalen <= 0) /* No TCP data */ |
89 | goto clear_out; |
90 | |
91 | if (tcpdatalen > H323_MAX_SIZE) |
92 | tcpdatalen = H323_MAX_SIZE; |
93 | |
94 | if (*data == NULL) { /* first TPKT */ |
95 | /* Get first TPKT pointer */ |
96 | tpkt = skb_header_pointer(skb, offset: tcpdataoff, len: tcpdatalen, |
97 | buffer: h323_buffer); |
98 | if (!tpkt) |
99 | goto clear_out; |
100 | |
101 | /* Validate TPKT identifier */ |
102 | if (tcpdatalen < 4 || tpkt[0] != 0x03 || tpkt[1] != 0) { |
103 | /* Netmeeting sends TPKT header and data separately */ |
104 | if (info->tpkt_len[dir] > 0) { |
105 | pr_debug("nf_ct_h323: previous packet " |
106 | "indicated separate TPKT data of %hu " |
107 | "bytes\n" , info->tpkt_len[dir]); |
108 | if (info->tpkt_len[dir] <= tcpdatalen) { |
109 | /* Yes, there was a TPKT header |
110 | * received */ |
111 | *data = tpkt; |
112 | *datalen = info->tpkt_len[dir]; |
113 | *dataoff = 0; |
114 | goto out; |
115 | } |
116 | |
117 | /* Fragmented TPKT */ |
118 | pr_debug("nf_ct_h323: fragmented TPKT\n" ); |
119 | goto clear_out; |
120 | } |
121 | |
122 | /* It is not even a TPKT */ |
123 | return 0; |
124 | } |
125 | tpktoff = 0; |
126 | } else { /* Next TPKT */ |
127 | tpktoff = *dataoff + *datalen; |
128 | tcpdatalen -= tpktoff; |
129 | if (tcpdatalen <= 4) /* No more TPKT */ |
130 | goto clear_out; |
131 | tpkt = *data + *datalen; |
132 | |
133 | /* Validate TPKT identifier */ |
134 | if (tpkt[0] != 0x03 || tpkt[1] != 0) |
135 | goto clear_out; |
136 | } |
137 | |
138 | /* Validate TPKT length */ |
139 | tpktlen = tpkt[2] * 256 + tpkt[3]; |
140 | if (tpktlen < 4) |
141 | goto clear_out; |
142 | if (tpktlen > tcpdatalen) { |
143 | if (tcpdatalen == 4) { /* Separate TPKT header */ |
144 | /* Netmeeting sends TPKT header and data separately */ |
145 | pr_debug("nf_ct_h323: separate TPKT header indicates " |
146 | "there will be TPKT data of %d bytes\n" , |
147 | tpktlen - 4); |
148 | info->tpkt_len[dir] = tpktlen - 4; |
149 | return 0; |
150 | } |
151 | |
152 | pr_debug("nf_ct_h323: incomplete TPKT (fragmented?)\n" ); |
153 | goto clear_out; |
154 | } |
155 | |
156 | /* This is the encapsulated data */ |
157 | *data = tpkt + 4; |
158 | *datalen = tpktlen - 4; |
159 | *dataoff = tpktoff + 4; |
160 | |
161 | out: |
162 | /* Clear TPKT length */ |
163 | info->tpkt_len[dir] = 0; |
164 | return 1; |
165 | |
166 | clear_out: |
167 | info->tpkt_len[dir] = 0; |
168 | return 0; |
169 | } |
170 | |
171 | static int get_h245_addr(struct nf_conn *ct, const unsigned char *data, |
172 | H245_TransportAddress *taddr, |
173 | union nf_inet_addr *addr, __be16 *port) |
174 | { |
175 | const unsigned char *p; |
176 | int len; |
177 | |
178 | if (taddr->choice != eH245_TransportAddress_unicastAddress) |
179 | return 0; |
180 | |
181 | switch (taddr->unicastAddress.choice) { |
182 | case eUnicastAddress_iPAddress: |
183 | if (nf_ct_l3num(ct) != AF_INET) |
184 | return 0; |
185 | p = data + taddr->unicastAddress.iPAddress.network; |
186 | len = 4; |
187 | break; |
188 | case eUnicastAddress_iP6Address: |
189 | if (nf_ct_l3num(ct) != AF_INET6) |
190 | return 0; |
191 | p = data + taddr->unicastAddress.iP6Address.network; |
192 | len = 16; |
193 | break; |
194 | default: |
195 | return 0; |
196 | } |
197 | |
198 | memcpy(addr, p, len); |
199 | memset((void *)addr + len, 0, sizeof(*addr) - len); |
200 | memcpy(port, p + len, sizeof(__be16)); |
201 | |
202 | return 1; |
203 | } |
204 | |
205 | static int expect_rtp_rtcp(struct sk_buff *skb, struct nf_conn *ct, |
206 | enum ip_conntrack_info ctinfo, |
207 | unsigned int protoff, |
208 | unsigned char **data, int dataoff, |
209 | H245_TransportAddress *taddr) |
210 | { |
211 | const struct nfct_h323_nat_hooks *nathook; |
212 | int dir = CTINFO2DIR(ctinfo); |
213 | int ret = 0; |
214 | __be16 port; |
215 | __be16 rtp_port, rtcp_port; |
216 | union nf_inet_addr addr; |
217 | struct nf_conntrack_expect *rtp_exp; |
218 | struct nf_conntrack_expect *rtcp_exp; |
219 | |
220 | /* Read RTP or RTCP address */ |
221 | if (!get_h245_addr(ct, data: *data, taddr, addr: &addr, port: &port) || |
222 | memcmp(p: &addr, q: &ct->tuplehash[dir].tuple.src.u3, size: sizeof(addr)) || |
223 | port == 0) |
224 | return 0; |
225 | |
226 | /* RTP port is even */ |
227 | rtp_port = port & ~htons(1); |
228 | rtcp_port = port | htons(1); |
229 | |
230 | /* Create expect for RTP */ |
231 | if ((rtp_exp = nf_ct_expect_alloc(me: ct)) == NULL) |
232 | return -1; |
233 | nf_ct_expect_init(rtp_exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct), |
234 | &ct->tuplehash[!dir].tuple.src.u3, |
235 | &ct->tuplehash[!dir].tuple.dst.u3, |
236 | IPPROTO_UDP, NULL, &rtp_port); |
237 | |
238 | /* Create expect for RTCP */ |
239 | if ((rtcp_exp = nf_ct_expect_alloc(me: ct)) == NULL) { |
240 | nf_ct_expect_put(exp: rtp_exp); |
241 | return -1; |
242 | } |
243 | nf_ct_expect_init(rtcp_exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct), |
244 | &ct->tuplehash[!dir].tuple.src.u3, |
245 | &ct->tuplehash[!dir].tuple.dst.u3, |
246 | IPPROTO_UDP, NULL, &rtcp_port); |
247 | |
248 | nathook = rcu_dereference(nfct_h323_nat_hook); |
249 | if (memcmp(p: &ct->tuplehash[dir].tuple.src.u3, |
250 | q: &ct->tuplehash[!dir].tuple.dst.u3, |
251 | size: sizeof(ct->tuplehash[dir].tuple.src.u3)) && |
252 | nathook && |
253 | nf_ct_l3num(ct) == NFPROTO_IPV4 && |
254 | ct->status & IPS_NAT_MASK) { |
255 | /* NAT needed */ |
256 | ret = nathook->nat_rtp_rtcp(skb, ct, ctinfo, protoff, data, dataoff, |
257 | taddr, port, rtp_port, rtp_exp, rtcp_exp); |
258 | } else { /* Conntrack only */ |
259 | if (nf_ct_expect_related(expect: rtp_exp, flags: 0) == 0) { |
260 | if (nf_ct_expect_related(expect: rtcp_exp, flags: 0) == 0) { |
261 | pr_debug("nf_ct_h323: expect RTP " ); |
262 | nf_ct_dump_tuple(t: &rtp_exp->tuple); |
263 | pr_debug("nf_ct_h323: expect RTCP " ); |
264 | nf_ct_dump_tuple(t: &rtcp_exp->tuple); |
265 | } else { |
266 | nf_ct_unexpect_related(exp: rtp_exp); |
267 | ret = -1; |
268 | } |
269 | } else |
270 | ret = -1; |
271 | } |
272 | |
273 | nf_ct_expect_put(exp: rtp_exp); |
274 | nf_ct_expect_put(exp: rtcp_exp); |
275 | |
276 | return ret; |
277 | } |
278 | |
279 | static int expect_t120(struct sk_buff *skb, |
280 | struct nf_conn *ct, |
281 | enum ip_conntrack_info ctinfo, |
282 | unsigned int protoff, |
283 | unsigned char **data, int dataoff, |
284 | H245_TransportAddress *taddr) |
285 | { |
286 | const struct nfct_h323_nat_hooks *nathook; |
287 | int dir = CTINFO2DIR(ctinfo); |
288 | int ret = 0; |
289 | __be16 port; |
290 | union nf_inet_addr addr; |
291 | struct nf_conntrack_expect *exp; |
292 | |
293 | /* Read T.120 address */ |
294 | if (!get_h245_addr(ct, data: *data, taddr, addr: &addr, port: &port) || |
295 | memcmp(p: &addr, q: &ct->tuplehash[dir].tuple.src.u3, size: sizeof(addr)) || |
296 | port == 0) |
297 | return 0; |
298 | |
299 | /* Create expect for T.120 connections */ |
300 | if ((exp = nf_ct_expect_alloc(me: ct)) == NULL) |
301 | return -1; |
302 | nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct), |
303 | &ct->tuplehash[!dir].tuple.src.u3, |
304 | &ct->tuplehash[!dir].tuple.dst.u3, |
305 | IPPROTO_TCP, NULL, &port); |
306 | exp->flags = NF_CT_EXPECT_PERMANENT; /* Accept multiple channels */ |
307 | |
308 | nathook = rcu_dereference(nfct_h323_nat_hook); |
309 | if (memcmp(p: &ct->tuplehash[dir].tuple.src.u3, |
310 | q: &ct->tuplehash[!dir].tuple.dst.u3, |
311 | size: sizeof(ct->tuplehash[dir].tuple.src.u3)) && |
312 | nathook && |
313 | nf_ct_l3num(ct) == NFPROTO_IPV4 && |
314 | ct->status & IPS_NAT_MASK) { |
315 | /* NAT needed */ |
316 | ret = nathook->nat_t120(skb, ct, ctinfo, protoff, data, |
317 | dataoff, taddr, port, exp); |
318 | } else { /* Conntrack only */ |
319 | if (nf_ct_expect_related(expect: exp, flags: 0) == 0) { |
320 | pr_debug("nf_ct_h323: expect T.120 " ); |
321 | nf_ct_dump_tuple(t: &exp->tuple); |
322 | } else |
323 | ret = -1; |
324 | } |
325 | |
326 | nf_ct_expect_put(exp); |
327 | |
328 | return ret; |
329 | } |
330 | |
331 | static int process_h245_channel(struct sk_buff *skb, |
332 | struct nf_conn *ct, |
333 | enum ip_conntrack_info ctinfo, |
334 | unsigned int protoff, |
335 | unsigned char **data, int dataoff, |
336 | H2250LogicalChannelParameters *channel) |
337 | { |
338 | int ret; |
339 | |
340 | if (channel->options & eH2250LogicalChannelParameters_mediaChannel) { |
341 | /* RTP */ |
342 | ret = expect_rtp_rtcp(skb, ct, ctinfo, protoff, data, dataoff, |
343 | taddr: &channel->mediaChannel); |
344 | if (ret < 0) |
345 | return -1; |
346 | } |
347 | |
348 | if (channel-> |
349 | options & eH2250LogicalChannelParameters_mediaControlChannel) { |
350 | /* RTCP */ |
351 | ret = expect_rtp_rtcp(skb, ct, ctinfo, protoff, data, dataoff, |
352 | taddr: &channel->mediaControlChannel); |
353 | if (ret < 0) |
354 | return -1; |
355 | } |
356 | |
357 | return 0; |
358 | } |
359 | |
360 | static int process_olc(struct sk_buff *skb, struct nf_conn *ct, |
361 | enum ip_conntrack_info ctinfo, |
362 | unsigned int protoff, |
363 | unsigned char **data, int dataoff, |
364 | OpenLogicalChannel *olc) |
365 | { |
366 | int ret; |
367 | |
368 | pr_debug("nf_ct_h323: OpenLogicalChannel\n" ); |
369 | |
370 | if (olc->forwardLogicalChannelParameters.multiplexParameters.choice == |
371 | eOpenLogicalChannel_forwardLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters) |
372 | { |
373 | ret = process_h245_channel(skb, ct, ctinfo, |
374 | protoff, data, dataoff, |
375 | channel: &olc-> |
376 | forwardLogicalChannelParameters. |
377 | multiplexParameters. |
378 | h2250LogicalChannelParameters); |
379 | if (ret < 0) |
380 | return -1; |
381 | } |
382 | |
383 | if ((olc->options & |
384 | eOpenLogicalChannel_reverseLogicalChannelParameters) && |
385 | (olc->reverseLogicalChannelParameters.options & |
386 | eOpenLogicalChannel_reverseLogicalChannelParameters_multiplexParameters) |
387 | && (olc->reverseLogicalChannelParameters.multiplexParameters. |
388 | choice == |
389 | eOpenLogicalChannel_reverseLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters)) |
390 | { |
391 | ret = |
392 | process_h245_channel(skb, ct, ctinfo, |
393 | protoff, data, dataoff, |
394 | channel: &olc-> |
395 | reverseLogicalChannelParameters. |
396 | multiplexParameters. |
397 | h2250LogicalChannelParameters); |
398 | if (ret < 0) |
399 | return -1; |
400 | } |
401 | |
402 | if ((olc->options & eOpenLogicalChannel_separateStack) && |
403 | olc->forwardLogicalChannelParameters.dataType.choice == |
404 | eDataType_data && |
405 | olc->forwardLogicalChannelParameters.dataType.data.application. |
406 | choice == eDataApplicationCapability_application_t120 && |
407 | olc->forwardLogicalChannelParameters.dataType.data.application. |
408 | t120.choice == eDataProtocolCapability_separateLANStack && |
409 | olc->separateStack.networkAddress.choice == |
410 | eNetworkAccessParameters_networkAddress_localAreaAddress) { |
411 | ret = expect_t120(skb, ct, ctinfo, protoff, data, dataoff, |
412 | taddr: &olc->separateStack.networkAddress. |
413 | localAreaAddress); |
414 | if (ret < 0) |
415 | return -1; |
416 | } |
417 | |
418 | return 0; |
419 | } |
420 | |
421 | static int process_olca(struct sk_buff *skb, struct nf_conn *ct, |
422 | enum ip_conntrack_info ctinfo, |
423 | unsigned int protoff, unsigned char **data, int dataoff, |
424 | OpenLogicalChannelAck *olca) |
425 | { |
426 | H2250LogicalChannelAckParameters *ack; |
427 | int ret; |
428 | |
429 | pr_debug("nf_ct_h323: OpenLogicalChannelAck\n" ); |
430 | |
431 | if ((olca->options & |
432 | eOpenLogicalChannelAck_reverseLogicalChannelParameters) && |
433 | (olca->reverseLogicalChannelParameters.options & |
434 | eOpenLogicalChannelAck_reverseLogicalChannelParameters_multiplexParameters) |
435 | && (olca->reverseLogicalChannelParameters.multiplexParameters. |
436 | choice == |
437 | eOpenLogicalChannelAck_reverseLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters)) |
438 | { |
439 | ret = process_h245_channel(skb, ct, ctinfo, |
440 | protoff, data, dataoff, |
441 | channel: &olca-> |
442 | reverseLogicalChannelParameters. |
443 | multiplexParameters. |
444 | h2250LogicalChannelParameters); |
445 | if (ret < 0) |
446 | return -1; |
447 | } |
448 | |
449 | if ((olca->options & |
450 | eOpenLogicalChannelAck_forwardMultiplexAckParameters) && |
451 | (olca->forwardMultiplexAckParameters.choice == |
452 | eOpenLogicalChannelAck_forwardMultiplexAckParameters_h2250LogicalChannelAckParameters)) |
453 | { |
454 | ack = &olca->forwardMultiplexAckParameters. |
455 | h2250LogicalChannelAckParameters; |
456 | if (ack->options & |
457 | eH2250LogicalChannelAckParameters_mediaChannel) { |
458 | /* RTP */ |
459 | ret = expect_rtp_rtcp(skb, ct, ctinfo, |
460 | protoff, data, dataoff, |
461 | taddr: &ack->mediaChannel); |
462 | if (ret < 0) |
463 | return -1; |
464 | } |
465 | |
466 | if (ack->options & |
467 | eH2250LogicalChannelAckParameters_mediaControlChannel) { |
468 | /* RTCP */ |
469 | ret = expect_rtp_rtcp(skb, ct, ctinfo, |
470 | protoff, data, dataoff, |
471 | taddr: &ack->mediaControlChannel); |
472 | if (ret < 0) |
473 | return -1; |
474 | } |
475 | } |
476 | |
477 | if ((olca->options & eOpenLogicalChannelAck_separateStack) && |
478 | olca->separateStack.networkAddress.choice == |
479 | eNetworkAccessParameters_networkAddress_localAreaAddress) { |
480 | ret = expect_t120(skb, ct, ctinfo, protoff, data, dataoff, |
481 | taddr: &olca->separateStack.networkAddress. |
482 | localAreaAddress); |
483 | if (ret < 0) |
484 | return -1; |
485 | } |
486 | |
487 | return 0; |
488 | } |
489 | |
490 | static int process_h245(struct sk_buff *skb, struct nf_conn *ct, |
491 | enum ip_conntrack_info ctinfo, |
492 | unsigned int protoff, unsigned char **data, int dataoff, |
493 | MultimediaSystemControlMessage *mscm) |
494 | { |
495 | switch (mscm->choice) { |
496 | case eMultimediaSystemControlMessage_request: |
497 | if (mscm->request.choice == |
498 | eRequestMessage_openLogicalChannel) { |
499 | return process_olc(skb, ct, ctinfo, |
500 | protoff, data, dataoff, |
501 | olc: &mscm->request.openLogicalChannel); |
502 | } |
503 | pr_debug("nf_ct_h323: H.245 Request %d\n" , |
504 | mscm->request.choice); |
505 | break; |
506 | case eMultimediaSystemControlMessage_response: |
507 | if (mscm->response.choice == |
508 | eResponseMessage_openLogicalChannelAck) { |
509 | return process_olca(skb, ct, ctinfo, |
510 | protoff, data, dataoff, |
511 | olca: &mscm->response. |
512 | openLogicalChannelAck); |
513 | } |
514 | pr_debug("nf_ct_h323: H.245 Response %d\n" , |
515 | mscm->response.choice); |
516 | break; |
517 | default: |
518 | pr_debug("nf_ct_h323: H.245 signal %d\n" , mscm->choice); |
519 | break; |
520 | } |
521 | |
522 | return 0; |
523 | } |
524 | |
525 | static int h245_help(struct sk_buff *skb, unsigned int protoff, |
526 | struct nf_conn *ct, enum ip_conntrack_info ctinfo) |
527 | { |
528 | static MultimediaSystemControlMessage mscm; |
529 | unsigned char *data = NULL; |
530 | int datalen; |
531 | int dataoff; |
532 | int ret; |
533 | |
534 | /* Until there's been traffic both ways, don't look in packets. */ |
535 | if (ctinfo != IP_CT_ESTABLISHED && ctinfo != IP_CT_ESTABLISHED_REPLY) |
536 | return NF_ACCEPT; |
537 | |
538 | pr_debug("nf_ct_h245: skblen = %u\n" , skb->len); |
539 | |
540 | spin_lock_bh(lock: &nf_h323_lock); |
541 | |
542 | /* Process each TPKT */ |
543 | while (get_tpkt_data(skb, protoff, ct, ctinfo, |
544 | data: &data, datalen: &datalen, dataoff: &dataoff)) { |
545 | pr_debug("nf_ct_h245: TPKT len=%d " , datalen); |
546 | nf_ct_dump_tuple(t: &ct->tuplehash[CTINFO2DIR(ctinfo)].tuple); |
547 | |
548 | /* Decode H.245 signal */ |
549 | ret = DecodeMultimediaSystemControlMessage(buf: data, sz: datalen, |
550 | mscm: &mscm); |
551 | if (ret < 0) { |
552 | pr_debug("nf_ct_h245: decoding error: %s\n" , |
553 | ret == H323_ERROR_BOUND ? |
554 | "out of bound" : "out of range" ); |
555 | /* We don't drop when decoding error */ |
556 | break; |
557 | } |
558 | |
559 | /* Process H.245 signal */ |
560 | if (process_h245(skb, ct, ctinfo, protoff, |
561 | data: &data, dataoff, mscm: &mscm) < 0) |
562 | goto drop; |
563 | } |
564 | |
565 | spin_unlock_bh(lock: &nf_h323_lock); |
566 | return NF_ACCEPT; |
567 | |
568 | drop: |
569 | spin_unlock_bh(lock: &nf_h323_lock); |
570 | nf_ct_helper_log(skb, ct, fmt: "cannot process H.245 message" ); |
571 | return NF_DROP; |
572 | } |
573 | |
574 | static const struct nf_conntrack_expect_policy h245_exp_policy = { |
575 | .max_expected = H323_RTP_CHANNEL_MAX * 4 + 2 /* T.120 */, |
576 | .timeout = 240, |
577 | }; |
578 | |
579 | static struct nf_conntrack_helper nf_conntrack_helper_h245 __read_mostly = { |
580 | .name = "H.245" , |
581 | .me = THIS_MODULE, |
582 | .tuple.src.l3num = AF_UNSPEC, |
583 | .tuple.dst.protonum = IPPROTO_UDP, |
584 | .help = h245_help, |
585 | .expect_policy = &h245_exp_policy, |
586 | }; |
587 | |
588 | int get_h225_addr(struct nf_conn *ct, unsigned char *data, |
589 | TransportAddress *taddr, |
590 | union nf_inet_addr *addr, __be16 *port) |
591 | { |
592 | const unsigned char *p; |
593 | int len; |
594 | |
595 | switch (taddr->choice) { |
596 | case eTransportAddress_ipAddress: |
597 | if (nf_ct_l3num(ct) != AF_INET) |
598 | return 0; |
599 | p = data + taddr->ipAddress.ip; |
600 | len = 4; |
601 | break; |
602 | case eTransportAddress_ip6Address: |
603 | if (nf_ct_l3num(ct) != AF_INET6) |
604 | return 0; |
605 | p = data + taddr->ip6Address.ip; |
606 | len = 16; |
607 | break; |
608 | default: |
609 | return 0; |
610 | } |
611 | |
612 | memcpy(addr, p, len); |
613 | memset((void *)addr + len, 0, sizeof(*addr) - len); |
614 | memcpy(port, p + len, sizeof(__be16)); |
615 | |
616 | return 1; |
617 | } |
618 | EXPORT_SYMBOL_GPL(get_h225_addr); |
619 | |
620 | static int expect_h245(struct sk_buff *skb, struct nf_conn *ct, |
621 | enum ip_conntrack_info ctinfo, |
622 | unsigned int protoff, unsigned char **data, int dataoff, |
623 | TransportAddress *taddr) |
624 | { |
625 | const struct nfct_h323_nat_hooks *nathook; |
626 | int dir = CTINFO2DIR(ctinfo); |
627 | int ret = 0; |
628 | __be16 port; |
629 | union nf_inet_addr addr; |
630 | struct nf_conntrack_expect *exp; |
631 | |
632 | /* Read h245Address */ |
633 | if (!get_h225_addr(ct, *data, taddr, &addr, &port) || |
634 | memcmp(p: &addr, q: &ct->tuplehash[dir].tuple.src.u3, size: sizeof(addr)) || |
635 | port == 0) |
636 | return 0; |
637 | |
638 | /* Create expect for h245 connection */ |
639 | if ((exp = nf_ct_expect_alloc(me: ct)) == NULL) |
640 | return -1; |
641 | nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct), |
642 | &ct->tuplehash[!dir].tuple.src.u3, |
643 | &ct->tuplehash[!dir].tuple.dst.u3, |
644 | IPPROTO_TCP, NULL, &port); |
645 | exp->helper = &nf_conntrack_helper_h245; |
646 | |
647 | nathook = rcu_dereference(nfct_h323_nat_hook); |
648 | if (memcmp(p: &ct->tuplehash[dir].tuple.src.u3, |
649 | q: &ct->tuplehash[!dir].tuple.dst.u3, |
650 | size: sizeof(ct->tuplehash[dir].tuple.src.u3)) && |
651 | nathook && |
652 | nf_ct_l3num(ct) == NFPROTO_IPV4 && |
653 | ct->status & IPS_NAT_MASK) { |
654 | /* NAT needed */ |
655 | ret = nathook->nat_h245(skb, ct, ctinfo, protoff, data, |
656 | dataoff, taddr, port, exp); |
657 | } else { /* Conntrack only */ |
658 | if (nf_ct_expect_related(expect: exp, flags: 0) == 0) { |
659 | pr_debug("nf_ct_q931: expect H.245 " ); |
660 | nf_ct_dump_tuple(t: &exp->tuple); |
661 | } else |
662 | ret = -1; |
663 | } |
664 | |
665 | nf_ct_expect_put(exp); |
666 | |
667 | return ret; |
668 | } |
669 | |
670 | /* If the calling party is on the same side of the forward-to party, |
671 | * we don't need to track the second call |
672 | */ |
673 | static int callforward_do_filter(struct net *net, |
674 | const union nf_inet_addr *src, |
675 | const union nf_inet_addr *dst, |
676 | u_int8_t family) |
677 | { |
678 | int ret = 0; |
679 | |
680 | switch (family) { |
681 | case AF_INET: { |
682 | struct flowi4 fl1, fl2; |
683 | struct rtable *rt1, *rt2; |
684 | |
685 | memset(&fl1, 0, sizeof(fl1)); |
686 | fl1.daddr = src->ip; |
687 | |
688 | memset(&fl2, 0, sizeof(fl2)); |
689 | fl2.daddr = dst->ip; |
690 | if (!nf_ip_route(net, dst: (struct dst_entry **)&rt1, |
691 | fl: flowi4_to_flowi(fl4: &fl1), strict: false)) { |
692 | if (!nf_ip_route(net, dst: (struct dst_entry **)&rt2, |
693 | fl: flowi4_to_flowi(fl4: &fl2), strict: false)) { |
694 | if (rt_nexthop(rt: rt1, daddr: fl1.daddr) == |
695 | rt_nexthop(rt: rt2, daddr: fl2.daddr) && |
696 | rt1->dst.dev == rt2->dst.dev) |
697 | ret = 1; |
698 | dst_release(dst: &rt2->dst); |
699 | } |
700 | dst_release(dst: &rt1->dst); |
701 | } |
702 | break; |
703 | } |
704 | #if IS_ENABLED(CONFIG_IPV6) |
705 | case AF_INET6: { |
706 | struct rt6_info *rt1, *rt2; |
707 | struct flowi6 fl1, fl2; |
708 | |
709 | memset(&fl1, 0, sizeof(fl1)); |
710 | fl1.daddr = src->in6; |
711 | |
712 | memset(&fl2, 0, sizeof(fl2)); |
713 | fl2.daddr = dst->in6; |
714 | if (!nf_ip6_route(net, dst: (struct dst_entry **)&rt1, |
715 | fl: flowi6_to_flowi(fl6: &fl1), strict: false)) { |
716 | if (!nf_ip6_route(net, dst: (struct dst_entry **)&rt2, |
717 | fl: flowi6_to_flowi(fl6: &fl2), strict: false)) { |
718 | if (ipv6_addr_equal(a1: rt6_nexthop(rt: rt1, daddr: &fl1.daddr), |
719 | a2: rt6_nexthop(rt: rt2, daddr: &fl2.daddr)) && |
720 | rt1->dst.dev == rt2->dst.dev) |
721 | ret = 1; |
722 | dst_release(dst: &rt2->dst); |
723 | } |
724 | dst_release(dst: &rt1->dst); |
725 | } |
726 | break; |
727 | } |
728 | #endif |
729 | } |
730 | return ret; |
731 | |
732 | } |
733 | |
734 | static int expect_callforwarding(struct sk_buff *skb, |
735 | struct nf_conn *ct, |
736 | enum ip_conntrack_info ctinfo, |
737 | unsigned int protoff, |
738 | unsigned char **data, int dataoff, |
739 | TransportAddress *taddr) |
740 | { |
741 | const struct nfct_h323_nat_hooks *nathook; |
742 | int dir = CTINFO2DIR(ctinfo); |
743 | int ret = 0; |
744 | __be16 port; |
745 | union nf_inet_addr addr; |
746 | struct nf_conntrack_expect *exp; |
747 | struct net *net = nf_ct_net(ct); |
748 | |
749 | /* Read alternativeAddress */ |
750 | if (!get_h225_addr(ct, *data, taddr, &addr, &port) || port == 0) |
751 | return 0; |
752 | |
753 | /* If the calling party is on the same side of the forward-to party, |
754 | * we don't need to track the second call |
755 | */ |
756 | if (callforward_filter && |
757 | callforward_do_filter(net, src: &addr, dst: &ct->tuplehash[!dir].tuple.src.u3, |
758 | family: nf_ct_l3num(ct))) { |
759 | pr_debug("nf_ct_q931: Call Forwarding not tracked\n" ); |
760 | return 0; |
761 | } |
762 | |
763 | /* Create expect for the second call leg */ |
764 | if ((exp = nf_ct_expect_alloc(me: ct)) == NULL) |
765 | return -1; |
766 | nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct), |
767 | &ct->tuplehash[!dir].tuple.src.u3, &addr, |
768 | IPPROTO_TCP, NULL, &port); |
769 | exp->helper = nf_conntrack_helper_q931; |
770 | |
771 | nathook = rcu_dereference(nfct_h323_nat_hook); |
772 | if (memcmp(p: &ct->tuplehash[dir].tuple.src.u3, |
773 | q: &ct->tuplehash[!dir].tuple.dst.u3, |
774 | size: sizeof(ct->tuplehash[dir].tuple.src.u3)) && |
775 | nathook && |
776 | nf_ct_l3num(ct) == NFPROTO_IPV4 && |
777 | ct->status & IPS_NAT_MASK) { |
778 | /* Need NAT */ |
779 | ret = nathook->nat_callforwarding(skb, ct, ctinfo, |
780 | protoff, data, dataoff, |
781 | taddr, port, exp); |
782 | } else { /* Conntrack only */ |
783 | if (nf_ct_expect_related(expect: exp, flags: 0) == 0) { |
784 | pr_debug("nf_ct_q931: expect Call Forwarding " ); |
785 | nf_ct_dump_tuple(t: &exp->tuple); |
786 | } else |
787 | ret = -1; |
788 | } |
789 | |
790 | nf_ct_expect_put(exp); |
791 | |
792 | return ret; |
793 | } |
794 | |
795 | static int process_setup(struct sk_buff *skb, struct nf_conn *ct, |
796 | enum ip_conntrack_info ctinfo, |
797 | unsigned int protoff, |
798 | unsigned char **data, int dataoff, |
799 | Setup_UUIE *setup) |
800 | { |
801 | const struct nfct_h323_nat_hooks *nathook; |
802 | int dir = CTINFO2DIR(ctinfo); |
803 | int ret; |
804 | int i; |
805 | __be16 port; |
806 | union nf_inet_addr addr; |
807 | |
808 | pr_debug("nf_ct_q931: Setup\n" ); |
809 | |
810 | if (setup->options & eSetup_UUIE_h245Address) { |
811 | ret = expect_h245(skb, ct, ctinfo, protoff, data, dataoff, |
812 | taddr: &setup->h245Address); |
813 | if (ret < 0) |
814 | return -1; |
815 | } |
816 | |
817 | nathook = rcu_dereference(nfct_h323_nat_hook); |
818 | if ((setup->options & eSetup_UUIE_destCallSignalAddress) && |
819 | nathook && nf_ct_l3num(ct) == NFPROTO_IPV4 && |
820 | ct->status & IPS_NAT_MASK && |
821 | get_h225_addr(ct, *data, &setup->destCallSignalAddress, |
822 | &addr, &port) && |
823 | memcmp(p: &addr, q: &ct->tuplehash[!dir].tuple.src.u3, size: sizeof(addr))) { |
824 | pr_debug("nf_ct_q931: set destCallSignalAddress %pI6:%hu->%pI6:%hu\n" , |
825 | &addr, ntohs(port), &ct->tuplehash[!dir].tuple.src.u3, |
826 | ntohs(ct->tuplehash[!dir].tuple.src.u.tcp.port)); |
827 | ret = nathook->set_h225_addr(skb, protoff, data, dataoff, |
828 | &setup->destCallSignalAddress, |
829 | &ct->tuplehash[!dir].tuple.src.u3, |
830 | ct->tuplehash[!dir].tuple.src.u.tcp.port); |
831 | if (ret < 0) |
832 | return -1; |
833 | } |
834 | |
835 | if ((setup->options & eSetup_UUIE_sourceCallSignalAddress) && |
836 | nathook && nf_ct_l3num(ct) == NFPROTO_IPV4 && |
837 | ct->status & IPS_NAT_MASK && |
838 | get_h225_addr(ct, *data, &setup->sourceCallSignalAddress, |
839 | &addr, &port) && |
840 | memcmp(p: &addr, q: &ct->tuplehash[!dir].tuple.dst.u3, size: sizeof(addr))) { |
841 | pr_debug("nf_ct_q931: set sourceCallSignalAddress %pI6:%hu->%pI6:%hu\n" , |
842 | &addr, ntohs(port), &ct->tuplehash[!dir].tuple.dst.u3, |
843 | ntohs(ct->tuplehash[!dir].tuple.dst.u.tcp.port)); |
844 | ret = nathook->set_h225_addr(skb, protoff, data, dataoff, |
845 | &setup->sourceCallSignalAddress, |
846 | &ct->tuplehash[!dir].tuple.dst.u3, |
847 | ct->tuplehash[!dir].tuple.dst.u.tcp.port); |
848 | if (ret < 0) |
849 | return -1; |
850 | } |
851 | |
852 | if (setup->options & eSetup_UUIE_fastStart) { |
853 | for (i = 0; i < setup->fastStart.count; i++) { |
854 | ret = process_olc(skb, ct, ctinfo, |
855 | protoff, data, dataoff, |
856 | olc: &setup->fastStart.item[i]); |
857 | if (ret < 0) |
858 | return -1; |
859 | } |
860 | } |
861 | |
862 | return 0; |
863 | } |
864 | |
865 | static int process_callproceeding(struct sk_buff *skb, |
866 | struct nf_conn *ct, |
867 | enum ip_conntrack_info ctinfo, |
868 | unsigned int protoff, |
869 | unsigned char **data, int dataoff, |
870 | CallProceeding_UUIE *callproc) |
871 | { |
872 | int ret; |
873 | int i; |
874 | |
875 | pr_debug("nf_ct_q931: CallProceeding\n" ); |
876 | |
877 | if (callproc->options & eCallProceeding_UUIE_h245Address) { |
878 | ret = expect_h245(skb, ct, ctinfo, protoff, data, dataoff, |
879 | taddr: &callproc->h245Address); |
880 | if (ret < 0) |
881 | return -1; |
882 | } |
883 | |
884 | if (callproc->options & eCallProceeding_UUIE_fastStart) { |
885 | for (i = 0; i < callproc->fastStart.count; i++) { |
886 | ret = process_olc(skb, ct, ctinfo, |
887 | protoff, data, dataoff, |
888 | olc: &callproc->fastStart.item[i]); |
889 | if (ret < 0) |
890 | return -1; |
891 | } |
892 | } |
893 | |
894 | return 0; |
895 | } |
896 | |
897 | static int process_connect(struct sk_buff *skb, struct nf_conn *ct, |
898 | enum ip_conntrack_info ctinfo, |
899 | unsigned int protoff, |
900 | unsigned char **data, int dataoff, |
901 | Connect_UUIE *connect) |
902 | { |
903 | int ret; |
904 | int i; |
905 | |
906 | pr_debug("nf_ct_q931: Connect\n" ); |
907 | |
908 | if (connect->options & eConnect_UUIE_h245Address) { |
909 | ret = expect_h245(skb, ct, ctinfo, protoff, data, dataoff, |
910 | taddr: &connect->h245Address); |
911 | if (ret < 0) |
912 | return -1; |
913 | } |
914 | |
915 | if (connect->options & eConnect_UUIE_fastStart) { |
916 | for (i = 0; i < connect->fastStart.count; i++) { |
917 | ret = process_olc(skb, ct, ctinfo, |
918 | protoff, data, dataoff, |
919 | olc: &connect->fastStart.item[i]); |
920 | if (ret < 0) |
921 | return -1; |
922 | } |
923 | } |
924 | |
925 | return 0; |
926 | } |
927 | |
928 | static int process_alerting(struct sk_buff *skb, struct nf_conn *ct, |
929 | enum ip_conntrack_info ctinfo, |
930 | unsigned int protoff, |
931 | unsigned char **data, int dataoff, |
932 | Alerting_UUIE *alert) |
933 | { |
934 | int ret; |
935 | int i; |
936 | |
937 | pr_debug("nf_ct_q931: Alerting\n" ); |
938 | |
939 | if (alert->options & eAlerting_UUIE_h245Address) { |
940 | ret = expect_h245(skb, ct, ctinfo, protoff, data, dataoff, |
941 | taddr: &alert->h245Address); |
942 | if (ret < 0) |
943 | return -1; |
944 | } |
945 | |
946 | if (alert->options & eAlerting_UUIE_fastStart) { |
947 | for (i = 0; i < alert->fastStart.count; i++) { |
948 | ret = process_olc(skb, ct, ctinfo, |
949 | protoff, data, dataoff, |
950 | olc: &alert->fastStart.item[i]); |
951 | if (ret < 0) |
952 | return -1; |
953 | } |
954 | } |
955 | |
956 | return 0; |
957 | } |
958 | |
959 | static int process_facility(struct sk_buff *skb, struct nf_conn *ct, |
960 | enum ip_conntrack_info ctinfo, |
961 | unsigned int protoff, |
962 | unsigned char **data, int dataoff, |
963 | Facility_UUIE *facility) |
964 | { |
965 | int ret; |
966 | int i; |
967 | |
968 | pr_debug("nf_ct_q931: Facility\n" ); |
969 | |
970 | if (facility->reason.choice == eFacilityReason_callForwarded) { |
971 | if (facility->options & eFacility_UUIE_alternativeAddress) |
972 | return expect_callforwarding(skb, ct, ctinfo, |
973 | protoff, data, dataoff, |
974 | taddr: &facility-> |
975 | alternativeAddress); |
976 | return 0; |
977 | } |
978 | |
979 | if (facility->options & eFacility_UUIE_h245Address) { |
980 | ret = expect_h245(skb, ct, ctinfo, protoff, data, dataoff, |
981 | taddr: &facility->h245Address); |
982 | if (ret < 0) |
983 | return -1; |
984 | } |
985 | |
986 | if (facility->options & eFacility_UUIE_fastStart) { |
987 | for (i = 0; i < facility->fastStart.count; i++) { |
988 | ret = process_olc(skb, ct, ctinfo, |
989 | protoff, data, dataoff, |
990 | olc: &facility->fastStart.item[i]); |
991 | if (ret < 0) |
992 | return -1; |
993 | } |
994 | } |
995 | |
996 | return 0; |
997 | } |
998 | |
999 | static int process_progress(struct sk_buff *skb, struct nf_conn *ct, |
1000 | enum ip_conntrack_info ctinfo, |
1001 | unsigned int protoff, |
1002 | unsigned char **data, int dataoff, |
1003 | Progress_UUIE *progress) |
1004 | { |
1005 | int ret; |
1006 | int i; |
1007 | |
1008 | pr_debug("nf_ct_q931: Progress\n" ); |
1009 | |
1010 | if (progress->options & eProgress_UUIE_h245Address) { |
1011 | ret = expect_h245(skb, ct, ctinfo, protoff, data, dataoff, |
1012 | taddr: &progress->h245Address); |
1013 | if (ret < 0) |
1014 | return -1; |
1015 | } |
1016 | |
1017 | if (progress->options & eProgress_UUIE_fastStart) { |
1018 | for (i = 0; i < progress->fastStart.count; i++) { |
1019 | ret = process_olc(skb, ct, ctinfo, |
1020 | protoff, data, dataoff, |
1021 | olc: &progress->fastStart.item[i]); |
1022 | if (ret < 0) |
1023 | return -1; |
1024 | } |
1025 | } |
1026 | |
1027 | return 0; |
1028 | } |
1029 | |
1030 | static int process_q931(struct sk_buff *skb, struct nf_conn *ct, |
1031 | enum ip_conntrack_info ctinfo, |
1032 | unsigned int protoff, unsigned char **data, int dataoff, |
1033 | Q931 *q931) |
1034 | { |
1035 | H323_UU_PDU *pdu = &q931->UUIE.h323_uu_pdu; |
1036 | int i; |
1037 | int ret = 0; |
1038 | |
1039 | switch (pdu->h323_message_body.choice) { |
1040 | case eH323_UU_PDU_h323_message_body_setup: |
1041 | ret = process_setup(skb, ct, ctinfo, protoff, data, dataoff, |
1042 | setup: &pdu->h323_message_body.setup); |
1043 | break; |
1044 | case eH323_UU_PDU_h323_message_body_callProceeding: |
1045 | ret = process_callproceeding(skb, ct, ctinfo, |
1046 | protoff, data, dataoff, |
1047 | callproc: &pdu->h323_message_body. |
1048 | callProceeding); |
1049 | break; |
1050 | case eH323_UU_PDU_h323_message_body_connect: |
1051 | ret = process_connect(skb, ct, ctinfo, protoff, data, dataoff, |
1052 | connect: &pdu->h323_message_body.connect); |
1053 | break; |
1054 | case eH323_UU_PDU_h323_message_body_alerting: |
1055 | ret = process_alerting(skb, ct, ctinfo, protoff, data, dataoff, |
1056 | alert: &pdu->h323_message_body.alerting); |
1057 | break; |
1058 | case eH323_UU_PDU_h323_message_body_facility: |
1059 | ret = process_facility(skb, ct, ctinfo, protoff, data, dataoff, |
1060 | facility: &pdu->h323_message_body.facility); |
1061 | break; |
1062 | case eH323_UU_PDU_h323_message_body_progress: |
1063 | ret = process_progress(skb, ct, ctinfo, protoff, data, dataoff, |
1064 | progress: &pdu->h323_message_body.progress); |
1065 | break; |
1066 | default: |
1067 | pr_debug("nf_ct_q931: Q.931 signal %d\n" , |
1068 | pdu->h323_message_body.choice); |
1069 | break; |
1070 | } |
1071 | |
1072 | if (ret < 0) |
1073 | return -1; |
1074 | |
1075 | if (pdu->options & eH323_UU_PDU_h245Control) { |
1076 | for (i = 0; i < pdu->h245Control.count; i++) { |
1077 | ret = process_h245(skb, ct, ctinfo, |
1078 | protoff, data, dataoff, |
1079 | mscm: &pdu->h245Control.item[i]); |
1080 | if (ret < 0) |
1081 | return -1; |
1082 | } |
1083 | } |
1084 | |
1085 | return 0; |
1086 | } |
1087 | |
1088 | static int q931_help(struct sk_buff *skb, unsigned int protoff, |
1089 | struct nf_conn *ct, enum ip_conntrack_info ctinfo) |
1090 | { |
1091 | static Q931 q931; |
1092 | unsigned char *data = NULL; |
1093 | int datalen; |
1094 | int dataoff; |
1095 | int ret; |
1096 | |
1097 | /* Until there's been traffic both ways, don't look in packets. */ |
1098 | if (ctinfo != IP_CT_ESTABLISHED && ctinfo != IP_CT_ESTABLISHED_REPLY) |
1099 | return NF_ACCEPT; |
1100 | |
1101 | pr_debug("nf_ct_q931: skblen = %u\n" , skb->len); |
1102 | |
1103 | spin_lock_bh(lock: &nf_h323_lock); |
1104 | |
1105 | /* Process each TPKT */ |
1106 | while (get_tpkt_data(skb, protoff, ct, ctinfo, |
1107 | data: &data, datalen: &datalen, dataoff: &dataoff)) { |
1108 | pr_debug("nf_ct_q931: TPKT len=%d " , datalen); |
1109 | nf_ct_dump_tuple(t: &ct->tuplehash[CTINFO2DIR(ctinfo)].tuple); |
1110 | |
1111 | /* Decode Q.931 signal */ |
1112 | ret = DecodeQ931(buf: data, sz: datalen, q931: &q931); |
1113 | if (ret < 0) { |
1114 | pr_debug("nf_ct_q931: decoding error: %s\n" , |
1115 | ret == H323_ERROR_BOUND ? |
1116 | "out of bound" : "out of range" ); |
1117 | /* We don't drop when decoding error */ |
1118 | break; |
1119 | } |
1120 | |
1121 | /* Process Q.931 signal */ |
1122 | if (process_q931(skb, ct, ctinfo, protoff, |
1123 | data: &data, dataoff, q931: &q931) < 0) |
1124 | goto drop; |
1125 | } |
1126 | |
1127 | spin_unlock_bh(lock: &nf_h323_lock); |
1128 | return NF_ACCEPT; |
1129 | |
1130 | drop: |
1131 | spin_unlock_bh(lock: &nf_h323_lock); |
1132 | nf_ct_helper_log(skb, ct, fmt: "cannot process Q.931 message" ); |
1133 | return NF_DROP; |
1134 | } |
1135 | |
1136 | static const struct nf_conntrack_expect_policy q931_exp_policy = { |
1137 | /* T.120 and H.245 */ |
1138 | .max_expected = H323_RTP_CHANNEL_MAX * 4 + 4, |
1139 | .timeout = 240, |
1140 | }; |
1141 | |
1142 | static struct nf_conntrack_helper nf_conntrack_helper_q931[] __read_mostly = { |
1143 | { |
1144 | .name = "Q.931" , |
1145 | .me = THIS_MODULE, |
1146 | .tuple.src.l3num = AF_INET, |
1147 | .tuple.src.u.tcp.port = cpu_to_be16(Q931_PORT), |
1148 | .tuple.dst.protonum = IPPROTO_TCP, |
1149 | .help = q931_help, |
1150 | .expect_policy = &q931_exp_policy, |
1151 | }, |
1152 | { |
1153 | .name = "Q.931" , |
1154 | .me = THIS_MODULE, |
1155 | .tuple.src.l3num = AF_INET6, |
1156 | .tuple.src.u.tcp.port = cpu_to_be16(Q931_PORT), |
1157 | .tuple.dst.protonum = IPPROTO_TCP, |
1158 | .help = q931_help, |
1159 | .expect_policy = &q931_exp_policy, |
1160 | }, |
1161 | }; |
1162 | |
1163 | static unsigned char *get_udp_data(struct sk_buff *skb, unsigned int protoff, |
1164 | int *datalen) |
1165 | { |
1166 | const struct udphdr *uh; |
1167 | struct udphdr _uh; |
1168 | int dataoff; |
1169 | |
1170 | uh = skb_header_pointer(skb, offset: protoff, len: sizeof(_uh), buffer: &_uh); |
1171 | if (uh == NULL) |
1172 | return NULL; |
1173 | dataoff = protoff + sizeof(_uh); |
1174 | if (dataoff >= skb->len) |
1175 | return NULL; |
1176 | *datalen = skb->len - dataoff; |
1177 | if (*datalen > H323_MAX_SIZE) |
1178 | *datalen = H323_MAX_SIZE; |
1179 | |
1180 | return skb_header_pointer(skb, offset: dataoff, len: *datalen, buffer: h323_buffer); |
1181 | } |
1182 | |
1183 | static struct nf_conntrack_expect *find_expect(struct nf_conn *ct, |
1184 | union nf_inet_addr *addr, |
1185 | __be16 port) |
1186 | { |
1187 | struct net *net = nf_ct_net(ct); |
1188 | struct nf_conntrack_expect *exp; |
1189 | struct nf_conntrack_tuple tuple; |
1190 | |
1191 | memset(&tuple.src.u3, 0, sizeof(tuple.src.u3)); |
1192 | tuple.src.u.tcp.port = 0; |
1193 | memcpy(&tuple.dst.u3, addr, sizeof(tuple.dst.u3)); |
1194 | tuple.dst.u.tcp.port = port; |
1195 | tuple.dst.protonum = IPPROTO_TCP; |
1196 | |
1197 | exp = __nf_ct_expect_find(net, zone: nf_ct_zone(ct), tuple: &tuple); |
1198 | if (exp && exp->master == ct) |
1199 | return exp; |
1200 | return NULL; |
1201 | } |
1202 | |
1203 | static int expect_q931(struct sk_buff *skb, struct nf_conn *ct, |
1204 | enum ip_conntrack_info ctinfo, |
1205 | unsigned int protoff, unsigned char **data, |
1206 | TransportAddress *taddr, int count) |
1207 | { |
1208 | struct nf_ct_h323_master *info = nfct_help_data(ct); |
1209 | const struct nfct_h323_nat_hooks *nathook; |
1210 | int dir = CTINFO2DIR(ctinfo); |
1211 | int ret = 0; |
1212 | int i; |
1213 | __be16 port; |
1214 | union nf_inet_addr addr; |
1215 | struct nf_conntrack_expect *exp; |
1216 | |
1217 | /* Look for the first related address */ |
1218 | for (i = 0; i < count; i++) { |
1219 | if (get_h225_addr(ct, *data, &taddr[i], &addr, &port) && |
1220 | memcmp(p: &addr, q: &ct->tuplehash[dir].tuple.src.u3, |
1221 | size: sizeof(addr)) == 0 && port != 0) |
1222 | break; |
1223 | } |
1224 | |
1225 | if (i >= count) /* Not found */ |
1226 | return 0; |
1227 | |
1228 | /* Create expect for Q.931 */ |
1229 | if ((exp = nf_ct_expect_alloc(me: ct)) == NULL) |
1230 | return -1; |
1231 | nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct), |
1232 | gkrouted_only ? /* only accept calls from GK? */ |
1233 | &ct->tuplehash[!dir].tuple.src.u3 : NULL, |
1234 | &ct->tuplehash[!dir].tuple.dst.u3, |
1235 | IPPROTO_TCP, NULL, &port); |
1236 | exp->helper = nf_conntrack_helper_q931; |
1237 | exp->flags = NF_CT_EXPECT_PERMANENT; /* Accept multiple calls */ |
1238 | |
1239 | nathook = rcu_dereference(nfct_h323_nat_hook); |
1240 | if (nathook && nf_ct_l3num(ct) == NFPROTO_IPV4 && |
1241 | ct->status & IPS_NAT_MASK) { /* Need NAT */ |
1242 | ret = nathook->nat_q931(skb, ct, ctinfo, protoff, data, |
1243 | taddr, i, port, exp); |
1244 | } else { /* Conntrack only */ |
1245 | if (nf_ct_expect_related(expect: exp, flags: 0) == 0) { |
1246 | pr_debug("nf_ct_ras: expect Q.931 " ); |
1247 | nf_ct_dump_tuple(t: &exp->tuple); |
1248 | |
1249 | /* Save port for looking up expect in processing RCF */ |
1250 | info->sig_port[dir] = port; |
1251 | } else |
1252 | ret = -1; |
1253 | } |
1254 | |
1255 | nf_ct_expect_put(exp); |
1256 | |
1257 | return ret; |
1258 | } |
1259 | |
1260 | static int process_grq(struct sk_buff *skb, struct nf_conn *ct, |
1261 | enum ip_conntrack_info ctinfo, |
1262 | unsigned int protoff, |
1263 | unsigned char **data, GatekeeperRequest *grq) |
1264 | { |
1265 | const struct nfct_h323_nat_hooks *nathook; |
1266 | |
1267 | pr_debug("nf_ct_ras: GRQ\n" ); |
1268 | |
1269 | nathook = rcu_dereference(nfct_h323_nat_hook); |
1270 | if (nathook && nf_ct_l3num(ct) == NFPROTO_IPV4 && |
1271 | ct->status & IPS_NAT_MASK) /* NATed */ |
1272 | return nathook->set_ras_addr(skb, ct, ctinfo, protoff, data, |
1273 | &grq->rasAddress, 1); |
1274 | return 0; |
1275 | } |
1276 | |
1277 | static int process_gcf(struct sk_buff *skb, struct nf_conn *ct, |
1278 | enum ip_conntrack_info ctinfo, |
1279 | unsigned int protoff, |
1280 | unsigned char **data, GatekeeperConfirm *gcf) |
1281 | { |
1282 | int dir = CTINFO2DIR(ctinfo); |
1283 | int ret = 0; |
1284 | __be16 port; |
1285 | union nf_inet_addr addr; |
1286 | struct nf_conntrack_expect *exp; |
1287 | |
1288 | pr_debug("nf_ct_ras: GCF\n" ); |
1289 | |
1290 | if (!get_h225_addr(ct, *data, &gcf->rasAddress, &addr, &port)) |
1291 | return 0; |
1292 | |
1293 | /* Registration port is the same as discovery port */ |
1294 | if (!memcmp(p: &addr, q: &ct->tuplehash[dir].tuple.src.u3, size: sizeof(addr)) && |
1295 | port == ct->tuplehash[dir].tuple.src.u.udp.port) |
1296 | return 0; |
1297 | |
1298 | /* Avoid RAS expectation loops. A GCF is never expected. */ |
1299 | if (test_bit(IPS_EXPECTED_BIT, &ct->status)) |
1300 | return 0; |
1301 | |
1302 | /* Need new expect */ |
1303 | if ((exp = nf_ct_expect_alloc(me: ct)) == NULL) |
1304 | return -1; |
1305 | nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct), |
1306 | &ct->tuplehash[!dir].tuple.src.u3, &addr, |
1307 | IPPROTO_UDP, NULL, &port); |
1308 | exp->helper = nf_conntrack_helper_ras; |
1309 | |
1310 | if (nf_ct_expect_related(expect: exp, flags: 0) == 0) { |
1311 | pr_debug("nf_ct_ras: expect RAS " ); |
1312 | nf_ct_dump_tuple(t: &exp->tuple); |
1313 | } else |
1314 | ret = -1; |
1315 | |
1316 | nf_ct_expect_put(exp); |
1317 | |
1318 | return ret; |
1319 | } |
1320 | |
1321 | static int process_rrq(struct sk_buff *skb, struct nf_conn *ct, |
1322 | enum ip_conntrack_info ctinfo, |
1323 | unsigned int protoff, |
1324 | unsigned char **data, RegistrationRequest *rrq) |
1325 | { |
1326 | struct nf_ct_h323_master *info = nfct_help_data(ct); |
1327 | const struct nfct_h323_nat_hooks *nathook; |
1328 | int ret; |
1329 | |
1330 | pr_debug("nf_ct_ras: RRQ\n" ); |
1331 | |
1332 | ret = expect_q931(skb, ct, ctinfo, protoff, data, |
1333 | taddr: rrq->callSignalAddress.item, |
1334 | count: rrq->callSignalAddress.count); |
1335 | if (ret < 0) |
1336 | return -1; |
1337 | |
1338 | nathook = rcu_dereference(nfct_h323_nat_hook); |
1339 | if (nathook && nf_ct_l3num(ct) == NFPROTO_IPV4 && |
1340 | ct->status & IPS_NAT_MASK) { |
1341 | ret = nathook->set_ras_addr(skb, ct, ctinfo, protoff, data, |
1342 | rrq->rasAddress.item, |
1343 | rrq->rasAddress.count); |
1344 | if (ret < 0) |
1345 | return -1; |
1346 | } |
1347 | |
1348 | if (rrq->options & eRegistrationRequest_timeToLive) { |
1349 | pr_debug("nf_ct_ras: RRQ TTL = %u seconds\n" , rrq->timeToLive); |
1350 | info->timeout = rrq->timeToLive; |
1351 | } else |
1352 | info->timeout = default_rrq_ttl; |
1353 | |
1354 | return 0; |
1355 | } |
1356 | |
1357 | static int process_rcf(struct sk_buff *skb, struct nf_conn *ct, |
1358 | enum ip_conntrack_info ctinfo, |
1359 | unsigned int protoff, |
1360 | unsigned char **data, RegistrationConfirm *rcf) |
1361 | { |
1362 | struct nf_ct_h323_master *info = nfct_help_data(ct); |
1363 | const struct nfct_h323_nat_hooks *nathook; |
1364 | int dir = CTINFO2DIR(ctinfo); |
1365 | int ret; |
1366 | struct nf_conntrack_expect *exp; |
1367 | |
1368 | pr_debug("nf_ct_ras: RCF\n" ); |
1369 | |
1370 | nathook = rcu_dereference(nfct_h323_nat_hook); |
1371 | if (nathook && nf_ct_l3num(ct) == NFPROTO_IPV4 && |
1372 | ct->status & IPS_NAT_MASK) { |
1373 | ret = nathook->set_sig_addr(skb, ct, ctinfo, protoff, data, |
1374 | rcf->callSignalAddress.item, |
1375 | rcf->callSignalAddress.count); |
1376 | if (ret < 0) |
1377 | return -1; |
1378 | } |
1379 | |
1380 | if (rcf->options & eRegistrationConfirm_timeToLive) { |
1381 | pr_debug("nf_ct_ras: RCF TTL = %u seconds\n" , rcf->timeToLive); |
1382 | info->timeout = rcf->timeToLive; |
1383 | } |
1384 | |
1385 | if (info->timeout > 0) { |
1386 | pr_debug("nf_ct_ras: set RAS connection timeout to " |
1387 | "%u seconds\n" , info->timeout); |
1388 | nf_ct_refresh(ct, skb, extra_jiffies: info->timeout * HZ); |
1389 | |
1390 | /* Set expect timeout */ |
1391 | spin_lock_bh(lock: &nf_conntrack_expect_lock); |
1392 | exp = find_expect(ct, addr: &ct->tuplehash[dir].tuple.dst.u3, |
1393 | port: info->sig_port[!dir]); |
1394 | if (exp) { |
1395 | pr_debug("nf_ct_ras: set Q.931 expect " |
1396 | "timeout to %u seconds for" , |
1397 | info->timeout); |
1398 | nf_ct_dump_tuple(t: &exp->tuple); |
1399 | mod_timer_pending(timer: &exp->timeout, |
1400 | expires: jiffies + info->timeout * HZ); |
1401 | } |
1402 | spin_unlock_bh(lock: &nf_conntrack_expect_lock); |
1403 | } |
1404 | |
1405 | return 0; |
1406 | } |
1407 | |
1408 | static int process_urq(struct sk_buff *skb, struct nf_conn *ct, |
1409 | enum ip_conntrack_info ctinfo, |
1410 | unsigned int protoff, |
1411 | unsigned char **data, UnregistrationRequest *urq) |
1412 | { |
1413 | struct nf_ct_h323_master *info = nfct_help_data(ct); |
1414 | const struct nfct_h323_nat_hooks *nathook; |
1415 | int dir = CTINFO2DIR(ctinfo); |
1416 | int ret; |
1417 | |
1418 | pr_debug("nf_ct_ras: URQ\n" ); |
1419 | |
1420 | nathook = rcu_dereference(nfct_h323_nat_hook); |
1421 | if (nathook && nf_ct_l3num(ct) == NFPROTO_IPV4 && |
1422 | ct->status & IPS_NAT_MASK) { |
1423 | ret = nathook->set_sig_addr(skb, ct, ctinfo, protoff, data, |
1424 | urq->callSignalAddress.item, |
1425 | urq->callSignalAddress.count); |
1426 | if (ret < 0) |
1427 | return -1; |
1428 | } |
1429 | |
1430 | /* Clear old expect */ |
1431 | nf_ct_remove_expectations(ct); |
1432 | info->sig_port[dir] = 0; |
1433 | info->sig_port[!dir] = 0; |
1434 | |
1435 | /* Give it 30 seconds for UCF or URJ */ |
1436 | nf_ct_refresh(ct, skb, extra_jiffies: 30 * HZ); |
1437 | |
1438 | return 0; |
1439 | } |
1440 | |
1441 | static int process_arq(struct sk_buff *skb, struct nf_conn *ct, |
1442 | enum ip_conntrack_info ctinfo, |
1443 | unsigned int protoff, |
1444 | unsigned char **data, AdmissionRequest *arq) |
1445 | { |
1446 | const struct nf_ct_h323_master *info = nfct_help_data(ct); |
1447 | const struct nfct_h323_nat_hooks *nathook; |
1448 | int dir = CTINFO2DIR(ctinfo); |
1449 | __be16 port; |
1450 | union nf_inet_addr addr; |
1451 | |
1452 | pr_debug("nf_ct_ras: ARQ\n" ); |
1453 | |
1454 | nathook = rcu_dereference(nfct_h323_nat_hook); |
1455 | if (!nathook) |
1456 | return 0; |
1457 | |
1458 | if ((arq->options & eAdmissionRequest_destCallSignalAddress) && |
1459 | get_h225_addr(ct, *data, &arq->destCallSignalAddress, |
1460 | &addr, &port) && |
1461 | !memcmp(p: &addr, q: &ct->tuplehash[dir].tuple.src.u3, size: sizeof(addr)) && |
1462 | port == info->sig_port[dir] && |
1463 | nf_ct_l3num(ct) == NFPROTO_IPV4 && |
1464 | ct->status & IPS_NAT_MASK) { |
1465 | /* Answering ARQ */ |
1466 | return nathook->set_h225_addr(skb, protoff, data, 0, |
1467 | &arq->destCallSignalAddress, |
1468 | &ct->tuplehash[!dir].tuple.dst.u3, |
1469 | info->sig_port[!dir]); |
1470 | } |
1471 | |
1472 | if ((arq->options & eAdmissionRequest_srcCallSignalAddress) && |
1473 | get_h225_addr(ct, *data, &arq->srcCallSignalAddress, |
1474 | &addr, &port) && |
1475 | !memcmp(p: &addr, q: &ct->tuplehash[dir].tuple.src.u3, size: sizeof(addr)) && |
1476 | nf_ct_l3num(ct) == NFPROTO_IPV4 && |
1477 | ct->status & IPS_NAT_MASK) { |
1478 | /* Calling ARQ */ |
1479 | return nathook->set_h225_addr(skb, protoff, data, 0, |
1480 | &arq->srcCallSignalAddress, |
1481 | &ct->tuplehash[!dir].tuple.dst.u3, |
1482 | port); |
1483 | } |
1484 | |
1485 | return 0; |
1486 | } |
1487 | |
1488 | static int process_acf(struct sk_buff *skb, struct nf_conn *ct, |
1489 | enum ip_conntrack_info ctinfo, |
1490 | unsigned int protoff, |
1491 | unsigned char **data, AdmissionConfirm *acf) |
1492 | { |
1493 | int dir = CTINFO2DIR(ctinfo); |
1494 | int ret = 0; |
1495 | __be16 port; |
1496 | union nf_inet_addr addr; |
1497 | struct nf_conntrack_expect *exp; |
1498 | |
1499 | pr_debug("nf_ct_ras: ACF\n" ); |
1500 | |
1501 | if (!get_h225_addr(ct, *data, &acf->destCallSignalAddress, |
1502 | &addr, &port)) |
1503 | return 0; |
1504 | |
1505 | if (!memcmp(p: &addr, q: &ct->tuplehash[dir].tuple.dst.u3, size: sizeof(addr))) { |
1506 | const struct nfct_h323_nat_hooks *nathook; |
1507 | |
1508 | /* Answering ACF */ |
1509 | nathook = rcu_dereference(nfct_h323_nat_hook); |
1510 | if (nathook && nf_ct_l3num(ct) == NFPROTO_IPV4 && |
1511 | ct->status & IPS_NAT_MASK) |
1512 | return nathook->set_sig_addr(skb, ct, ctinfo, protoff, |
1513 | data, |
1514 | &acf->destCallSignalAddress, 1); |
1515 | return 0; |
1516 | } |
1517 | |
1518 | /* Need new expect */ |
1519 | if ((exp = nf_ct_expect_alloc(me: ct)) == NULL) |
1520 | return -1; |
1521 | nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct), |
1522 | &ct->tuplehash[!dir].tuple.src.u3, &addr, |
1523 | IPPROTO_TCP, NULL, &port); |
1524 | exp->flags = NF_CT_EXPECT_PERMANENT; |
1525 | exp->helper = nf_conntrack_helper_q931; |
1526 | |
1527 | if (nf_ct_expect_related(expect: exp, flags: 0) == 0) { |
1528 | pr_debug("nf_ct_ras: expect Q.931 " ); |
1529 | nf_ct_dump_tuple(t: &exp->tuple); |
1530 | } else |
1531 | ret = -1; |
1532 | |
1533 | nf_ct_expect_put(exp); |
1534 | |
1535 | return ret; |
1536 | } |
1537 | |
1538 | static int process_lrq(struct sk_buff *skb, struct nf_conn *ct, |
1539 | enum ip_conntrack_info ctinfo, |
1540 | unsigned int protoff, |
1541 | unsigned char **data, LocationRequest *lrq) |
1542 | { |
1543 | const struct nfct_h323_nat_hooks *nathook; |
1544 | |
1545 | pr_debug("nf_ct_ras: LRQ\n" ); |
1546 | |
1547 | nathook = rcu_dereference(nfct_h323_nat_hook); |
1548 | if (nathook && nf_ct_l3num(ct) == NFPROTO_IPV4 && |
1549 | ct->status & IPS_NAT_MASK) |
1550 | return nathook->set_ras_addr(skb, ct, ctinfo, protoff, data, |
1551 | &lrq->replyAddress, 1); |
1552 | return 0; |
1553 | } |
1554 | |
1555 | static int process_lcf(struct sk_buff *skb, struct nf_conn *ct, |
1556 | enum ip_conntrack_info ctinfo, |
1557 | unsigned int protoff, |
1558 | unsigned char **data, LocationConfirm *lcf) |
1559 | { |
1560 | int dir = CTINFO2DIR(ctinfo); |
1561 | int ret = 0; |
1562 | __be16 port; |
1563 | union nf_inet_addr addr; |
1564 | struct nf_conntrack_expect *exp; |
1565 | |
1566 | pr_debug("nf_ct_ras: LCF\n" ); |
1567 | |
1568 | if (!get_h225_addr(ct, *data, &lcf->callSignalAddress, |
1569 | &addr, &port)) |
1570 | return 0; |
1571 | |
1572 | /* Need new expect for call signal */ |
1573 | if ((exp = nf_ct_expect_alloc(me: ct)) == NULL) |
1574 | return -1; |
1575 | nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct), |
1576 | &ct->tuplehash[!dir].tuple.src.u3, &addr, |
1577 | IPPROTO_TCP, NULL, &port); |
1578 | exp->flags = NF_CT_EXPECT_PERMANENT; |
1579 | exp->helper = nf_conntrack_helper_q931; |
1580 | |
1581 | if (nf_ct_expect_related(expect: exp, flags: 0) == 0) { |
1582 | pr_debug("nf_ct_ras: expect Q.931 " ); |
1583 | nf_ct_dump_tuple(t: &exp->tuple); |
1584 | } else |
1585 | ret = -1; |
1586 | |
1587 | nf_ct_expect_put(exp); |
1588 | |
1589 | /* Ignore rasAddress */ |
1590 | |
1591 | return ret; |
1592 | } |
1593 | |
1594 | static int process_irr(struct sk_buff *skb, struct nf_conn *ct, |
1595 | enum ip_conntrack_info ctinfo, |
1596 | unsigned int protoff, |
1597 | unsigned char **data, InfoRequestResponse *irr) |
1598 | { |
1599 | const struct nfct_h323_nat_hooks *nathook; |
1600 | int ret; |
1601 | |
1602 | pr_debug("nf_ct_ras: IRR\n" ); |
1603 | |
1604 | nathook = rcu_dereference(nfct_h323_nat_hook); |
1605 | if (nathook && nf_ct_l3num(ct) == NFPROTO_IPV4 && |
1606 | ct->status & IPS_NAT_MASK) { |
1607 | ret = nathook->set_ras_addr(skb, ct, ctinfo, protoff, data, |
1608 | &irr->rasAddress, 1); |
1609 | if (ret < 0) |
1610 | return -1; |
1611 | |
1612 | ret = nathook->set_sig_addr(skb, ct, ctinfo, protoff, data, |
1613 | irr->callSignalAddress.item, |
1614 | irr->callSignalAddress.count); |
1615 | if (ret < 0) |
1616 | return -1; |
1617 | } |
1618 | |
1619 | return 0; |
1620 | } |
1621 | |
1622 | static int process_ras(struct sk_buff *skb, struct nf_conn *ct, |
1623 | enum ip_conntrack_info ctinfo, |
1624 | unsigned int protoff, |
1625 | unsigned char **data, RasMessage *ras) |
1626 | { |
1627 | switch (ras->choice) { |
1628 | case eRasMessage_gatekeeperRequest: |
1629 | return process_grq(skb, ct, ctinfo, protoff, data, |
1630 | grq: &ras->gatekeeperRequest); |
1631 | case eRasMessage_gatekeeperConfirm: |
1632 | return process_gcf(skb, ct, ctinfo, protoff, data, |
1633 | gcf: &ras->gatekeeperConfirm); |
1634 | case eRasMessage_registrationRequest: |
1635 | return process_rrq(skb, ct, ctinfo, protoff, data, |
1636 | rrq: &ras->registrationRequest); |
1637 | case eRasMessage_registrationConfirm: |
1638 | return process_rcf(skb, ct, ctinfo, protoff, data, |
1639 | rcf: &ras->registrationConfirm); |
1640 | case eRasMessage_unregistrationRequest: |
1641 | return process_urq(skb, ct, ctinfo, protoff, data, |
1642 | urq: &ras->unregistrationRequest); |
1643 | case eRasMessage_admissionRequest: |
1644 | return process_arq(skb, ct, ctinfo, protoff, data, |
1645 | arq: &ras->admissionRequest); |
1646 | case eRasMessage_admissionConfirm: |
1647 | return process_acf(skb, ct, ctinfo, protoff, data, |
1648 | acf: &ras->admissionConfirm); |
1649 | case eRasMessage_locationRequest: |
1650 | return process_lrq(skb, ct, ctinfo, protoff, data, |
1651 | lrq: &ras->locationRequest); |
1652 | case eRasMessage_locationConfirm: |
1653 | return process_lcf(skb, ct, ctinfo, protoff, data, |
1654 | lcf: &ras->locationConfirm); |
1655 | case eRasMessage_infoRequestResponse: |
1656 | return process_irr(skb, ct, ctinfo, protoff, data, |
1657 | irr: &ras->infoRequestResponse); |
1658 | default: |
1659 | pr_debug("nf_ct_ras: RAS message %d\n" , ras->choice); |
1660 | break; |
1661 | } |
1662 | |
1663 | return 0; |
1664 | } |
1665 | |
1666 | static int ras_help(struct sk_buff *skb, unsigned int protoff, |
1667 | struct nf_conn *ct, enum ip_conntrack_info ctinfo) |
1668 | { |
1669 | static RasMessage ras; |
1670 | unsigned char *data; |
1671 | int datalen = 0; |
1672 | int ret; |
1673 | |
1674 | pr_debug("nf_ct_ras: skblen = %u\n" , skb->len); |
1675 | |
1676 | spin_lock_bh(lock: &nf_h323_lock); |
1677 | |
1678 | /* Get UDP data */ |
1679 | data = get_udp_data(skb, protoff, datalen: &datalen); |
1680 | if (data == NULL) |
1681 | goto accept; |
1682 | pr_debug("nf_ct_ras: RAS message len=%d " , datalen); |
1683 | nf_ct_dump_tuple(t: &ct->tuplehash[CTINFO2DIR(ctinfo)].tuple); |
1684 | |
1685 | /* Decode RAS message */ |
1686 | ret = DecodeRasMessage(buf: data, sz: datalen, ras: &ras); |
1687 | if (ret < 0) { |
1688 | pr_debug("nf_ct_ras: decoding error: %s\n" , |
1689 | ret == H323_ERROR_BOUND ? |
1690 | "out of bound" : "out of range" ); |
1691 | goto accept; |
1692 | } |
1693 | |
1694 | /* Process RAS message */ |
1695 | if (process_ras(skb, ct, ctinfo, protoff, data: &data, ras: &ras) < 0) |
1696 | goto drop; |
1697 | |
1698 | accept: |
1699 | spin_unlock_bh(lock: &nf_h323_lock); |
1700 | return NF_ACCEPT; |
1701 | |
1702 | drop: |
1703 | spin_unlock_bh(lock: &nf_h323_lock); |
1704 | nf_ct_helper_log(skb, ct, fmt: "cannot process RAS message" ); |
1705 | return NF_DROP; |
1706 | } |
1707 | |
1708 | static const struct nf_conntrack_expect_policy ras_exp_policy = { |
1709 | .max_expected = 32, |
1710 | .timeout = 240, |
1711 | }; |
1712 | |
1713 | static struct nf_conntrack_helper nf_conntrack_helper_ras[] __read_mostly = { |
1714 | { |
1715 | .name = "RAS" , |
1716 | .me = THIS_MODULE, |
1717 | .tuple.src.l3num = AF_INET, |
1718 | .tuple.src.u.udp.port = cpu_to_be16(RAS_PORT), |
1719 | .tuple.dst.protonum = IPPROTO_UDP, |
1720 | .help = ras_help, |
1721 | .expect_policy = &ras_exp_policy, |
1722 | }, |
1723 | { |
1724 | .name = "RAS" , |
1725 | .me = THIS_MODULE, |
1726 | .tuple.src.l3num = AF_INET6, |
1727 | .tuple.src.u.udp.port = cpu_to_be16(RAS_PORT), |
1728 | .tuple.dst.protonum = IPPROTO_UDP, |
1729 | .help = ras_help, |
1730 | .expect_policy = &ras_exp_policy, |
1731 | }, |
1732 | }; |
1733 | |
1734 | static int __init h323_helper_init(void) |
1735 | { |
1736 | int ret; |
1737 | |
1738 | ret = nf_conntrack_helper_register(&nf_conntrack_helper_h245); |
1739 | if (ret < 0) |
1740 | return ret; |
1741 | ret = nf_conntrack_helpers_register(nf_conntrack_helper_q931, |
1742 | ARRAY_SIZE(nf_conntrack_helper_q931)); |
1743 | if (ret < 0) |
1744 | goto err1; |
1745 | ret = nf_conntrack_helpers_register(nf_conntrack_helper_ras, |
1746 | ARRAY_SIZE(nf_conntrack_helper_ras)); |
1747 | if (ret < 0) |
1748 | goto err2; |
1749 | |
1750 | return 0; |
1751 | err2: |
1752 | nf_conntrack_helpers_unregister(nf_conntrack_helper_q931, |
1753 | ARRAY_SIZE(nf_conntrack_helper_q931)); |
1754 | err1: |
1755 | nf_conntrack_helper_unregister(&nf_conntrack_helper_h245); |
1756 | return ret; |
1757 | } |
1758 | |
1759 | static void __exit h323_helper_exit(void) |
1760 | { |
1761 | nf_conntrack_helpers_unregister(nf_conntrack_helper_ras, |
1762 | ARRAY_SIZE(nf_conntrack_helper_ras)); |
1763 | nf_conntrack_helpers_unregister(nf_conntrack_helper_q931, |
1764 | ARRAY_SIZE(nf_conntrack_helper_q931)); |
1765 | nf_conntrack_helper_unregister(&nf_conntrack_helper_h245); |
1766 | } |
1767 | |
1768 | static void __exit nf_conntrack_h323_fini(void) |
1769 | { |
1770 | h323_helper_exit(); |
1771 | kfree(objp: h323_buffer); |
1772 | pr_debug("nf_ct_h323: fini\n" ); |
1773 | } |
1774 | |
1775 | static int __init nf_conntrack_h323_init(void) |
1776 | { |
1777 | int ret; |
1778 | |
1779 | NF_CT_HELPER_BUILD_BUG_ON(sizeof(struct nf_ct_h323_master)); |
1780 | |
1781 | h323_buffer = kmalloc(H323_MAX_SIZE + 1, GFP_KERNEL); |
1782 | if (!h323_buffer) |
1783 | return -ENOMEM; |
1784 | ret = h323_helper_init(); |
1785 | if (ret < 0) |
1786 | goto err1; |
1787 | pr_debug("nf_ct_h323: init success\n" ); |
1788 | return 0; |
1789 | err1: |
1790 | kfree(objp: h323_buffer); |
1791 | return ret; |
1792 | } |
1793 | |
1794 | module_init(nf_conntrack_h323_init); |
1795 | module_exit(nf_conntrack_h323_fini); |
1796 | |
1797 | MODULE_AUTHOR("Jing Min Zhao <zhaojingmin@users.sourceforge.net>" ); |
1798 | MODULE_DESCRIPTION("H.323 connection tracking helper" ); |
1799 | MODULE_LICENSE("GPL" ); |
1800 | MODULE_ALIAS("ip_conntrack_h323" ); |
1801 | MODULE_ALIAS_NFCT_HELPER("RAS" ); |
1802 | MODULE_ALIAS_NFCT_HELPER("Q.931" ); |
1803 | MODULE_ALIAS_NFCT_HELPER("H.245" ); |
1804 | |