1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
|
/*
en50221 encoder An implementation for libdvb
an implementation for the en50221 transport layer
Copyright (C) 2004, 2005 Manu Abraham <abraham.manu@gmail.com>
Copyright (C) 2005 Julian Scheel (julian at jusst dot de)
Copyright (C) 2006 Andrew de Quincey (adq_dvb@lidskialf.net)
This library is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as
published by the Free Software Foundation; either version 2.1 of
the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <string.h>
#include <libdvbmisc/dvbmisc.h>
#include <pthread.h>
#include <libucsi/mpeg/descriptor.h>
#include "en50221_app_ca.h"
#include "asn_1.h"
// tags supported by this resource
#define TAG_CA_INFO_ENQUIRY 0x9f8030
#define TAG_CA_INFO 0x9f8031
#define TAG_CA_PMT 0x9f8032
#define TAG_CA_PMT_REPLY 0x9f8033
struct en50221_app_ca {
struct en50221_app_send_functions *funcs;
en50221_app_ca_info_callback ca_info_callback;
void *ca_info_callback_arg;
en50221_app_ca_pmt_reply_callback ca_pmt_reply_callback;
void *ca_pmt_reply_callback_arg;
pthread_mutex_t lock;
};
struct ca_pmt_descriptor {
uint8_t *descriptor;
uint16_t length;
struct ca_pmt_descriptor *next;
};
struct ca_pmt_stream {
uint8_t stream_type;
uint16_t pid;
struct ca_pmt_descriptor *descriptors;
uint32_t descriptors_length;
uint32_t descriptors_count;
struct ca_pmt_stream *next;
};
static int en50221_ca_extract_pmt_descriptors(struct mpeg_pmt_section *pmt,
struct ca_pmt_descriptor **outdescriptors);
static int en50221_ca_extract_streams(struct mpeg_pmt_section *pmt,
struct ca_pmt_stream **outstreams);
static void en50221_ca_try_move_pmt_descriptors(struct ca_pmt_descriptor **pmt_descriptors,
struct ca_pmt_stream **pmt_streams);
static uint32_t en50221_ca_calculate_length(struct ca_pmt_descriptor *pmt_descriptors,
uint32_t *pmt_descriptors_length,
struct ca_pmt_stream *pmt_streams);
static int en50221_app_ca_parse_info(struct en50221_app_ca *ca,
uint8_t slot_id,
uint16_t session_number,
uint8_t * data, uint32_t data_length);
static int en50221_app_ca_parse_reply(struct en50221_app_ca *ca,
uint8_t slot_id,
uint16_t session_number,
uint8_t * data,
uint32_t data_length);
struct en50221_app_ca *en50221_app_ca_create(struct en50221_app_send_functions *funcs)
{
struct en50221_app_ca *ca = NULL;
// create structure and set it up
ca = malloc(sizeof(struct en50221_app_ca));
if (ca == NULL) {
return NULL;
}
ca->funcs = funcs;
ca->ca_info_callback = NULL;
ca->ca_pmt_reply_callback = NULL;
pthread_mutex_init(&ca->lock, NULL);
// done
return ca;
}
void en50221_app_ca_destroy(struct en50221_app_ca *ca)
{
pthread_mutex_destroy(&ca->lock);
free(ca);
}
void en50221_app_ca_register_info_callback(struct en50221_app_ca *ca,
en50221_app_ca_info_callback
callback, void *arg)
{
pthread_mutex_lock(&ca->lock);
ca->ca_info_callback = callback;
ca->ca_info_callback_arg = arg;
pthread_mutex_unlock(&ca->lock);
}
void en50221_app_ca_register_pmt_reply_callback(struct en50221_app_ca *ca,
en50221_app_ca_pmt_reply_callback
callback, void *arg)
{
pthread_mutex_lock(&ca->lock);
ca->ca_pmt_reply_callback = callback;
ca->ca_pmt_reply_callback_arg = arg;
pthread_mutex_unlock(&ca->lock);
}
int en50221_app_ca_info_enq(struct en50221_app_ca *ca,
uint16_t session_number)
{
uint8_t data[4];
data[0] = (TAG_CA_INFO_ENQUIRY >> 16) & 0xFF;
data[1] = (TAG_CA_INFO_ENQUIRY >> 8) & 0xFF;
data[2] = TAG_CA_INFO_ENQUIRY & 0xFF;
data[3] = 0;
return ca->funcs->send_data(ca->funcs->arg, session_number, data, 4);
}
int en50221_app_ca_pmt(struct en50221_app_ca *ca,
uint16_t session_number,
uint8_t * ca_pmt, uint32_t ca_pmt_length)
{
uint8_t buf[10];
// set up the tag
buf[0] = (TAG_CA_PMT >> 16) & 0xFF;
buf[1] = (TAG_CA_PMT >> 8) & 0xFF;
buf[2] = TAG_CA_PMT & 0xFF;
// encode the length field
int length_field_len;
if ((length_field_len = asn_1_encode(ca_pmt_length, buf + 3, 3)) < 0) {
return -1;
}
// build the iovecs
struct iovec iov[2];
iov[0].iov_base = buf;
iov[0].iov_len = 3 + length_field_len;
iov[1].iov_base = ca_pmt;
iov[1].iov_len = ca_pmt_length;
// create the data and send it
return ca->funcs->send_datav(ca->funcs->arg, session_number, iov, 2);
}
int en50221_app_ca_message(struct en50221_app_ca *ca,
uint8_t slot_id,
uint16_t session_number,
uint32_t resource_id,
uint8_t * data, uint32_t data_length)
{
(void) resource_id;
// get the tag
if (data_length < 3) {
print(LOG_LEVEL, ERROR, 1, "Received short data\n");
return -1;
}
uint32_t tag = (data[0] << 16) | (data[1] << 8) | data[2];
switch (tag) {
case TAG_CA_INFO:
return en50221_app_ca_parse_info(ca, slot_id,
session_number, data + 3,
data_length - 3);
case TAG_CA_PMT_REPLY:
return en50221_app_ca_parse_reply(ca, slot_id,
session_number, data + 3,
data_length - 3);
}
print(LOG_LEVEL, ERROR, 1, "Received unexpected tag %x\n", tag);
return -1;
}
int en50221_ca_format_pmt(struct mpeg_pmt_section *pmt, uint8_t * data,
uint32_t data_length, int move_ca_descriptors,
uint8_t ca_pmt_list_management,
uint8_t ca_pmt_cmd_id)
{
struct ca_pmt_descriptor *pmt_descriptors = NULL;
uint32_t pmt_descriptors_length = 0;
struct ca_pmt_stream *pmt_streams = NULL;
uint32_t total_required_length = 0;
struct ca_pmt_descriptor *cur_d;
struct ca_pmt_stream *cur_s;
int result = -1;
// extract the descriptors and streams
if (en50221_ca_extract_pmt_descriptors(pmt, &pmt_descriptors))
goto cleanup;
if (en50221_ca_extract_streams(pmt, &pmt_streams))
goto cleanup;
// try and merge them if we have no PMT descriptors
if ((pmt_descriptors == NULL) && move_ca_descriptors) {
en50221_ca_try_move_pmt_descriptors(&pmt_descriptors,
&pmt_streams);
}
// calculate the length of all descriptors/streams and the total length required
total_required_length =
en50221_ca_calculate_length(pmt_descriptors,
&pmt_descriptors_length,
pmt_streams);
// ensure we were supplied with enough data
if (total_required_length > data_length) {
goto cleanup;
}
// format the start of the PMT
uint32_t data_pos = 0;
data[data_pos++] = ca_pmt_list_management;
data[data_pos++] = mpeg_pmt_section_program_number(pmt) >> 8;
data[data_pos++] = mpeg_pmt_section_program_number(pmt);
data[data_pos++] =
(pmt->head.version_number << 1) | pmt->head.
current_next_indicator;
data[data_pos++] = (pmt_descriptors_length >> 8) & 0x0f;
data[data_pos++] = pmt_descriptors_length;
// append the PMT descriptors
if (pmt_descriptors_length) {
data[data_pos++] = ca_pmt_cmd_id;
cur_d = pmt_descriptors;
while (cur_d) {
memcpy(data + data_pos, cur_d->descriptor,
cur_d->length);
data_pos += cur_d->length;
cur_d = cur_d->next;
}
}
// now, append the streams
cur_s = pmt_streams;
while (cur_s) {
data[data_pos++] = cur_s->stream_type;
data[data_pos++] = (cur_s->pid >> 8) & 0x1f;
data[data_pos++] = cur_s->pid;
data[data_pos++] = (cur_s->descriptors_length >> 8) & 0x0f;
data[data_pos++] = cur_s->descriptors_length;
// append the stream descriptors
if (cur_s->descriptors_length) {
data[data_pos++] = ca_pmt_cmd_id;
cur_d = cur_s->descriptors;
while (cur_d) {
memcpy(data + data_pos, cur_d->descriptor,
cur_d->length);
data_pos += cur_d->length;
cur_d = cur_d->next;
}
}
cur_s = cur_s->next;
}
result = data_pos;
cleanup:
// free the PMT descriptors
cur_d = pmt_descriptors;
while (cur_d) {
struct ca_pmt_descriptor *next = cur_d->next;
free(cur_d);
cur_d = next;
}
// free the streams
cur_s = pmt_streams;
while (cur_s) {
struct ca_pmt_stream *next_s = cur_s->next;
// free the stream descriptors
cur_d = cur_s->descriptors;
while (cur_d) {
struct ca_pmt_descriptor *next_d = cur_d->next;
free(cur_d);
cur_d = next_d;
}
free(cur_s);
cur_s = next_s;
}
return result;
}
static int en50221_ca_extract_pmt_descriptors(struct mpeg_pmt_section *pmt,
struct ca_pmt_descriptor **outdescriptors)
{
struct ca_pmt_descriptor *descriptors = NULL;
struct ca_pmt_descriptor *descriptors_tail = NULL;
struct ca_pmt_descriptor *cur_d;
struct descriptor *cur_descriptor;
mpeg_pmt_section_descriptors_for_each(pmt, cur_descriptor) {
if (cur_descriptor->tag == dtag_mpeg_ca) {
// create a new structure for this one
struct ca_pmt_descriptor *new_d =
malloc(sizeof(struct ca_pmt_descriptor));
if (new_d == NULL) {
goto error_exit;
}
new_d->descriptor = (uint8_t *) cur_descriptor;
new_d->length = cur_descriptor->len + 2;
new_d->next = NULL;
// append it to the list
if (descriptors == NULL) {
descriptors = new_d;
} else {
descriptors_tail->next = new_d;
}
descriptors_tail = new_d;
}
}
*outdescriptors = descriptors;
return 0;
error_exit:
cur_d = descriptors;
while (cur_d) {
struct ca_pmt_descriptor *next = cur_d->next;
free(cur_d);
cur_d = next;
}
return -1;
}
static int en50221_ca_extract_streams(struct mpeg_pmt_section *pmt,
struct ca_pmt_stream **outstreams)
{
struct ca_pmt_stream *streams = NULL;
struct ca_pmt_stream *streams_tail = NULL;
struct mpeg_pmt_stream *cur_stream;
struct descriptor *cur_descriptor;
struct ca_pmt_stream *cur_s;
mpeg_pmt_section_streams_for_each(pmt, cur_stream) {
struct ca_pmt_descriptor *descriptors_tail = NULL;
// create a new structure
struct ca_pmt_stream *new_s =
malloc(sizeof(struct ca_pmt_stream));
if (new_s == NULL) {
goto exit_cleanup;
}
new_s->stream_type = cur_stream->stream_type;
new_s->pid = cur_stream->pid;
new_s->descriptors = NULL;
new_s->next = NULL;
new_s->descriptors_count = 0;
// append it to the list
if (streams == NULL) {
streams = new_s;
} else {
streams_tail->next = new_s;
}
streams_tail = new_s;
// now process the descriptors
mpeg_pmt_stream_descriptors_for_each(cur_stream,
cur_descriptor) {
if (cur_descriptor->tag == dtag_mpeg_ca) {
// create a new structure
struct ca_pmt_descriptor *new_d =
malloc(sizeof(struct ca_pmt_descriptor));
if (new_d == NULL) {
goto exit_cleanup;
}
new_d->descriptor =
(uint8_t *) cur_descriptor;
new_d->length = cur_descriptor->len + 2;
new_d->next = NULL;
// append it to the list
if (new_s->descriptors == NULL) {
new_s->descriptors = new_d;
} else {
descriptors_tail->next = new_d;
}
descriptors_tail = new_d;
new_s->descriptors_count++;
}
}
}
*outstreams = streams;
return 0;
exit_cleanup:
// free the streams
cur_s = streams;
while (cur_s) {
struct ca_pmt_stream *next_s = cur_s->next;
// free the stream descriptors
struct ca_pmt_descriptor *cur_d = cur_s->descriptors;
while (cur_d) {
struct ca_pmt_descriptor *next_d = cur_d->next;
free(cur_d);
cur_d = next_d;
}
free(cur_s);
cur_s = next_s;
}
return -1;
}
static void en50221_ca_try_move_pmt_descriptors(struct ca_pmt_descriptor **pmt_descriptors,
struct ca_pmt_stream **pmt_streams)
{
// get the first stream
struct ca_pmt_stream *first_stream = *pmt_streams;
if (first_stream == NULL)
return;
// Check that all the other streams with CA descriptors have exactly the same CA descriptors
struct ca_pmt_stream *cur_stream = first_stream->next;
while (cur_stream) {
// if there are differing numbers of descriptors, exit right now
if (cur_stream->descriptors_count != first_stream->descriptors_count)
return;
// now verify the descriptors match
struct ca_pmt_descriptor *cur_descriptor = cur_stream->descriptors;
struct ca_pmt_descriptor *first_cur_descriptor = first_stream->descriptors;
while (cur_descriptor) {
// check the descriptors are the same length
if (cur_descriptor->length != first_cur_descriptor->length)
return;
// check their contents match
if (memcmp(cur_descriptor->descriptor,
first_cur_descriptor->descriptor,
cur_descriptor->length)) {
return;
}
// move to next
cur_descriptor = cur_descriptor->next;
first_cur_descriptor = first_cur_descriptor->next;
}
// move to next
cur_stream = cur_stream->next;
}
// if we end up here, all descriptors in all streams matched
// hook the first stream's descriptors into the PMT's
*pmt_descriptors = first_stream->descriptors;
first_stream->descriptors = NULL;
first_stream->descriptors_count = 0;
// now free up all the descriptors in the other streams
cur_stream = first_stream->next;
while (cur_stream) {
struct ca_pmt_descriptor *cur_descriptor = cur_stream->descriptors;
while (cur_descriptor) {
struct ca_pmt_descriptor *next = cur_descriptor->next;
free(cur_descriptor);
cur_descriptor = next;
}
cur_stream->descriptors = NULL;
cur_stream->descriptors_count = 0;
cur_stream = cur_stream->next;
}
}
static uint32_t en50221_ca_calculate_length(struct ca_pmt_descriptor *pmt_descriptors,
uint32_t *pmt_descriptors_length,
struct ca_pmt_stream *pmt_streams)
{
uint32_t total_required_length = 6; // header
struct ca_pmt_stream *cur_s;
// calcuate the PMT descriptors length
(*pmt_descriptors_length) = 0;
struct ca_pmt_descriptor *cur_d = pmt_descriptors;
while (cur_d) {
(*pmt_descriptors_length) += cur_d->length;
cur_d = cur_d->next;
}
// add on 1 byte for the ca_pmt_cmd_id if we have some descriptors.
if (*pmt_descriptors_length)
(*pmt_descriptors_length)++;
// update the total required length
total_required_length += *pmt_descriptors_length;
// calculate the length of descriptors in the streams
cur_s = pmt_streams;
while (cur_s) {
// calculate the size of descriptors in this stream
cur_s->descriptors_length = 0;
cur_d = cur_s->descriptors;
while (cur_d) {
cur_s->descriptors_length += cur_d->length;
cur_d = cur_d->next;
}
// add on 1 byte for the ca_pmt_cmd_id if we have some descriptors.
if (cur_s->descriptors_length)
cur_s->descriptors_length++;
// update the total required length;
total_required_length += 5 + cur_s->descriptors_length;
cur_s = cur_s->next;
}
// done
return total_required_length;
}
static int en50221_app_ca_parse_info(struct en50221_app_ca *ca,
uint8_t slot_id,
uint16_t session_number,
uint8_t * data, uint32_t data_length)
{
// first of all, decode the length field
uint16_t asn_data_length;
int length_field_len;
if ((length_field_len = asn_1_decode(&asn_data_length, data, data_length)) < 0) {
print(LOG_LEVEL, ERROR, 1, "ASN.1 decode error\n");
return -1;
}
// check it
if (asn_data_length > (data_length - length_field_len)) {
print(LOG_LEVEL, ERROR, 1, "Received short data\n");
return -1;
}
data += length_field_len;
// parse
uint32_t ca_id_count = asn_data_length / 2;
// byteswap the IDs
uint16_t *ids = (uint16_t *) data;
uint32_t i;
for (i = 0; i < ca_id_count; i++) {
bswap16(data);
data += 2;
}
// tell the app
pthread_mutex_lock(&ca->lock);
en50221_app_ca_info_callback cb = ca->ca_info_callback;
void *cb_arg = ca->ca_info_callback_arg;
pthread_mutex_unlock(&ca->lock);
if (cb) {
return cb(cb_arg, slot_id, session_number, ca_id_count,
ids);
}
return 0;
}
static int en50221_app_ca_parse_reply(struct en50221_app_ca *ca,
uint8_t slot_id,
uint16_t session_number,
uint8_t * data, uint32_t data_length)
{
// first of all, decode the length field
uint16_t asn_data_length;
int length_field_len;
if ((length_field_len = asn_1_decode(&asn_data_length, data, data_length)) < 0) {
print(LOG_LEVEL, ERROR, 1, "ASN.1 decode error\n");
return -1;
}
// check it
if (asn_data_length < 4) {
print(LOG_LEVEL, ERROR, 1, "Received short data\n");
return -1;
}
if (asn_data_length > (data_length - length_field_len)) {
print(LOG_LEVEL, ERROR, 1, "Received short data\n");
return -1;
}
data += length_field_len;
data_length -= length_field_len;
// process the reply table to fix endian issues
uint32_t pos = 4;
bswap16(data);
while (pos < asn_data_length) {
bswap16(data + pos);
pos += 3;
}
// tell the app
pthread_mutex_lock(&ca->lock);
en50221_app_ca_pmt_reply_callback cb = ca->ca_pmt_reply_callback;
void *cb_arg = ca->ca_pmt_reply_callback_arg;
pthread_mutex_unlock(&ca->lock);
if (cb) {
return cb(cb_arg, slot_id, session_number,
(struct en50221_app_pmt_reply *) data,
asn_data_length);
}
return 0;
}
|