Remove angular brackets from Doxygen comments; Doxygen confuses them for HTML.
[libav.git] / libavformat / rdt.c
CommitLineData
e9dea59f
RB
1/*
2 * Realmedia RTSP protocol (RDT) support.
3 * Copyright (c) 2007 Ronald S. Bultje
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22/**
ba87f080 23 * @file
e9dea59f
RB
24 * @brief Realmedia RTSP protocol (RDT) support
25 * @author Ronald S. Bultje <rbultje@ronald.bitfreak.net>
26 */
27
28#include "avformat.h"
29#include "libavutil/avstring.h"
302879cb 30#include "rtpdec.h"
e9dea59f
RB
31#include "rdt.h"
32#include "libavutil/base64.h"
33#include "libavutil/md5.h"
34#include "rm.h"
35#include "internal.h"
9106a698 36#include "libavcodec/get_bits.h"
e9dea59f 37
accc248f 38struct RDTDemuxContext {
63f412f9 39 AVFormatContext *ic; /**< the containing (RTSP) demux context */
4f602856
RB
40 /** Each RDT stream-set (represented by one RTSPStream) can contain
41 * multiple streams (of the same content, but with possibly different
42 * codecs/bitrates). Each such stream is represented by one AVStream
43 * in the AVFormatContext, and this variable points to the offset in
44 * that array such that the first is the first stream of this set. */
45 AVStream **streams;
46 int n_streams; /**< streams with identifical content in this set */
accc248f
RB
47 void *dynamic_protocol_context;
48 DynamicPayloadPacketHandlerProc parse_packet;
9168f7e6 49 uint32_t prev_timestamp;
7960e18f 50 int prev_set_id, prev_stream_id;
accc248f
RB
51};
52
53RDTDemuxContext *
e0d1eabf 54ff_rdt_parse_open(AVFormatContext *ic, int first_stream_of_set_idx,
accc248f
RB
55 void *priv_data, RTPDynamicProtocolHandler *handler)
56{
57 RDTDemuxContext *s = av_mallocz(sizeof(RDTDemuxContext));
58 if (!s)
59 return NULL;
60
61 s->ic = ic;
4f602856
RB
62 s->streams = &ic->streams[first_stream_of_set_idx];
63 do {
64 s->n_streams++;
65 } while (first_stream_of_set_idx + s->n_streams < ic->nb_streams &&
66 s->streams[s->n_streams]->priv_data == s->streams[0]->priv_data);
239dec21 67 s->prev_set_id = -1;
7960e18f 68 s->prev_stream_id = -1;
239dec21 69 s->prev_timestamp = -1;
84f0aba1 70 s->parse_packet = handler ? handler->parse_packet : NULL;
accc248f
RB
71 s->dynamic_protocol_context = priv_data;
72
73 return s;
74}
75
76void
77ff_rdt_parse_close(RDTDemuxContext *s)
78{
3ca45429
RB
79 int i;
80
81 for (i = 1; i < s->n_streams; i++)
82 s->streams[i]->priv_data = NULL;
83
accc248f
RB
84 av_free(s);
85}
86
ed0aacc7 87struct PayloadContext {
ff13ba92 88 AVFormatContext *rmctx;
886e89d0 89 RMStream *rmst[MAX_STREAMS];
ff13ba92
RB
90 uint8_t *mlti_data;
91 unsigned int mlti_data_size;
4fce284c 92 char buffer[RTP_MAX_PACKET_LENGTH + FF_INPUT_BUFFER_PADDING_SIZE];
5d88c264 93 int audio_pkt_cnt; /**< remaining audio packets in rmdec */
ed0aacc7 94};
ff13ba92 95
e9dea59f
RB
96void
97ff_rdt_calc_response_and_checksum(char response[41], char chksum[9],
98 const char *challenge)
99{
100 int ch_len = strlen (challenge), i;
101 unsigned char zres[16],
102 buf[64] = { 0xa1, 0xe9, 0x14, 0x9d, 0x0e, 0x6b, 0x3b, 0x59 };
103#define XOR_TABLE_SIZE 37
104 const unsigned char xor_table[XOR_TABLE_SIZE] = {
105 0x05, 0x18, 0x74, 0xd0, 0x0d, 0x09, 0x02, 0x53,
106 0xc0, 0x01, 0x05, 0x05, 0x67, 0x03, 0x19, 0x70,
107 0x08, 0x27, 0x66, 0x10, 0x10, 0x72, 0x08, 0x09,
108 0x63, 0x11, 0x03, 0x71, 0x08, 0x08, 0x70, 0x02,
109 0x10, 0x57, 0x05, 0x18, 0x54 };
110
111 /* some (length) checks */
112 if (ch_len == 40) /* what a hack... */
113 ch_len = 32;
114 else if (ch_len > 56)
115 ch_len = 56;
116 memcpy(buf + 8, challenge, ch_len);
117
118 /* xor challenge bytewise with xor_table */
119 for (i = 0; i < XOR_TABLE_SIZE; i++)
120 buf[8 + i] ^= xor_table[i];
121
122 av_md5_sum(zres, buf, 64);
ddbeb954 123 ff_data_to_hex(response, zres, 16, 1);
e9dea59f
RB
124
125 /* add tail */
126 strcpy (response + 32, "01d0a8e3");
127
128 /* calculate checksum */
129 for (i = 0; i < 8; i++)
130 chksum[i] = response[i * 4];
131 chksum[8] = 0;
132}
ff13ba92
RB
133
134static int
ed0aacc7 135rdt_load_mdpr (PayloadContext *rdt, AVStream *st, int rule_nr)
ff13ba92 136{
a4b8cb3c 137 ByteIOContext pb;
ff13ba92
RB
138 int size;
139 uint32_t tag;
140
141 /**
142 * Layout of the MLTI chunk:
0baf34d8
DB
143 * 4: MLTI
144 * 2: number of streams
ff13ba92 145 * Then for each stream ([number_of_streams] times):
0baf34d8
DB
146 * 2: mdpr index
147 * 2: number of mdpr chunks
ff13ba92 148 * Then for each mdpr chunk ([number_of_mdpr_chunks] times):
0baf34d8
DB
149 * 4: size
150 * [size]: data
ff13ba92
RB
151 * we skip MDPR chunks until we reach the one of the stream
152 * we're interested in, and forward that ([size]+[data]) to
153 * the RM demuxer to parse the stream-specific header data.
154 */
155 if (!rdt->mlti_data)
156 return -1;
a4b8cb3c
RB
157 init_put_byte(&pb, rdt->mlti_data, rdt->mlti_data_size, 0,
158 NULL, NULL, NULL, NULL);
159 tag = get_le32(&pb);
ff13ba92
RB
160 if (tag == MKTAG('M', 'L', 'T', 'I')) {
161 int num, chunk_nr;
162
163 /* read index of MDPR chunk numbers */
a4b8cb3c 164 num = get_be16(&pb);
ff13ba92
RB
165 if (rule_nr < 0 || rule_nr >= num)
166 return -1;
a4b8cb3c
RB
167 url_fskip(&pb, rule_nr * 2);
168 chunk_nr = get_be16(&pb);
169 url_fskip(&pb, (num - 1 - rule_nr) * 2);
ff13ba92
RB
170
171 /* read MDPR chunks */
a4b8cb3c 172 num = get_be16(&pb);
ff13ba92
RB
173 if (chunk_nr >= num)
174 return -1;
175 while (chunk_nr--)
a4b8cb3c
RB
176 url_fskip(&pb, get_be32(&pb));
177 size = get_be32(&pb);
ff13ba92
RB
178 } else {
179 size = rdt->mlti_data_size;
a4b8cb3c 180 url_fseek(&pb, 0, SEEK_SET);
ff13ba92 181 }
7c68a177 182 if (ff_rm_read_mdpr_codecdata(rdt->rmctx, &pb, st, rdt->rmst[st->index], size) < 0)
ff13ba92
RB
183 return -1;
184
ff13ba92
RB
185 return 0;
186}
187
4fce284c
RB
188/**
189 * Actual data handling.
190 */
191
985b05d3
RB
192int
193ff_rdt_parse_header(const uint8_t *buf, int len,
e269ab79
RB
194 int *pset_id, int *pseq_no, int *pstream_id,
195 int *pis_keyframe, uint32_t *ptimestamp)
4fce284c 196{
6bafd6f5 197 GetBitContext gb;
43af8b2b
RB
198 int consumed = 0, set_id, seq_no, stream_id, is_keyframe,
199 len_included, need_reliable;
6bafd6f5 200 uint32_t timestamp;
4fce284c 201
e3b7216b
RB
202 /* skip status packets */
203 while (len >= 5 && buf[1] == 0xFF /* status packet */) {
204 int pkt_len;
205
206 if (!(buf[0] & 0x80))
207 return -1; /* not followed by a data packet */
208
209 pkt_len = AV_RB16(buf+3);
210 buf += pkt_len;
211 len -= pkt_len;
212 consumed += pkt_len;
4fce284c 213 }
43af8b2b 214 if (len < 16)
985b05d3 215 return -1;
9e164392
RB
216 /**
217 * Layout of the header (in bits):
218 * 1: len_included
219 * Flag indicating whether this header includes a length field;
220 * this can be used to concatenate multiple RDT packets in a
221 * single UDP/TCP data frame and is used to precede RDT data
222 * by stream status packets
223 * 1: need_reliable
224 * Flag indicating whether this header includes a "reliable
225 * sequence number"; these are apparently sequence numbers of
226 * data packets alone. For data packets, this flag is always
227 * set, according to the Real documentation [1]
228 * 5: set_id
229 * ID of a set of streams of identical content, possibly with
230 * different codecs or bitrates
231 * 1: is_reliable
232 * Flag set for certain streams deemed less tolerable for packet
233 * loss
234 * 16: seq_no
235 * Packet sequence number; if >=0xFF00, this is a non-data packet
236 * containing stream status info, the second byte indicates the
237 * type of status packet (see wireshark docs / source code [2])
238 * if (len_included) {
239 * 16: packet_len
240 * } else {
241 * packet_len = remainder of UDP/TCP frame
242 * }
243 * 1: is_back_to_back
244 * Back-to-Back flag; used for timing, set for one in every 10
245 * packets, according to the Real documentation [1]
246 * 1: is_slow_data
247 * Slow-data flag; currently unused, according to Real docs [1]
248 * 5: stream_id
249 * ID of the stream within this particular set of streams
250 * 1: is_no_keyframe
251 * Non-keyframe flag (unset if packet belongs to a keyframe)
252 * 32: timestamp (PTS)
253 * if (set_id == 0x1F) {
254 * 16: set_id (extended set-of-streams ID; see set_id)
255 * }
256 * if (need_reliable) {
257 * 16: reliable_seq_no
258 * Reliable sequence number (see need_reliable)
259 * }
260 * if (stream_id == 0x3F) {
261 * 16: stream_id (extended stream ID; see stream_id)
262 * }
263 * [1] https://protocol.helixcommunity.org/files/2005/devdocs/RDT_Feature_Level_20.txt
264 * [2] http://www.wireshark.org/docs/dfref/r/rdt.html and
265 * http://anonsvn.wireshark.org/viewvc/trunk/epan/dissectors/packet-rdt.c
266 */
6bafd6f5 267 init_get_bits(&gb, buf, len << 3);
43af8b2b
RB
268 len_included = get_bits1(&gb);
269 need_reliable = get_bits1(&gb);
6bafd6f5
RB
270 set_id = get_bits(&gb, 5);
271 skip_bits(&gb, 1);
272 seq_no = get_bits(&gb, 16);
43af8b2b
RB
273 if (len_included)
274 skip_bits(&gb, 16);
6bafd6f5
RB
275 skip_bits(&gb, 2);
276 stream_id = get_bits(&gb, 5);
277 is_keyframe = !get_bits1(&gb);
278 timestamp = get_bits_long(&gb, 32);
43af8b2b
RB
279 if (set_id == 0x1f)
280 set_id = get_bits(&gb, 16);
281 if (need_reliable)
90e0450f 282 skip_bits(&gb, 16);
43af8b2b
RB
283 if (stream_id == 0x1f)
284 stream_id = get_bits(&gb, 16);
4fce284c 285
6bafd6f5
RB
286 if (pset_id) *pset_id = set_id;
287 if (pseq_no) *pseq_no = seq_no;
288 if (pstream_id) *pstream_id = stream_id;
289 if (pis_keyframe) *pis_keyframe = is_keyframe;
290 if (ptimestamp) *ptimestamp = timestamp;
291
292 return consumed + (get_bits_count(&gb) >> 3);
4fce284c
RB
293}
294
295/**< return 0 on packet, no more left, 1 on packet, 1 on partial packet... */
296static int
1a45a9f4 297rdt_parse_packet (AVFormatContext *ctx, PayloadContext *rdt, AVStream *st,
9b932b8a 298 AVPacket *pkt, uint32_t *timestamp,
4fce284c
RB
299 const uint8_t *buf, int len, int flags)
300{
4fce284c 301 int seq = 1, res;
a4b8cb3c 302 ByteIOContext pb;
4fce284c 303
a15ebf34 304 if (rdt->audio_pkt_cnt == 0) {
4fce284c
RB
305 int pos;
306
a4b8cb3c 307 init_put_byte(&pb, buf, len, 0, NULL, NULL, NULL, NULL);
a68d44ed 308 flags = (flags & RTP_FLAG_KEY) ? 2 : 0;
7c68a177 309 res = ff_rm_parse_packet (rdt->rmctx, &pb, st, rdt->rmst[st->index], len, pkt,
34bddc39 310 &seq, flags, *timestamp);
a4b8cb3c 311 pos = url_ftell(&pb);
4fce284c
RB
312 if (res < 0)
313 return res;
c5efef7b
RB
314 if (res > 0) {
315 if (st->codec->codec_id == CODEC_ID_AAC) {
c8829279
RB
316 memcpy (rdt->buffer, buf + pos, len - pos);
317 rdt->rmctx->pb = av_alloc_put_byte (rdt->buffer, len - pos, 0,
318 NULL, NULL, NULL, NULL);
c5efef7b
RB
319 }
320 goto get_cache;
4fce284c
RB
321 }
322 } else {
c5efef7b 323get_cache:
a9f84821 324 rdt->audio_pkt_cnt =
ade8fb4d 325 ff_rm_retrieve_cache (rdt->rmctx, rdt->rmctx->pb,
7c68a177 326 st, rdt->rmst[st->index], pkt);
5d88c264 327 if (rdt->audio_pkt_cnt == 0 &&
4fce284c 328 st->codec->codec_id == CODEC_ID_AAC)
a4b8cb3c 329 av_freep(&rdt->rmctx->pb);
4fce284c
RB
330 }
331 pkt->stream_index = st->index;
332 pkt->pts = *timestamp;
333
5d88c264 334 return rdt->audio_pkt_cnt > 0;
4fce284c
RB
335}
336
337int
accc248f 338ff_rdt_parse_packet(RDTDemuxContext *s, AVPacket *pkt,
4fce284c
RB
339 const uint8_t *buf, int len)
340{
114732f4 341 int seq_no, flags = 0, stream_id, set_id, is_keyframe;
4fce284c
RB
342 uint32_t timestamp;
343 int rv= 0;
344
3ff2a062
RB
345 if (!s->parse_packet)
346 return -1;
347
7960e18f 348 if (!buf && s->prev_stream_id != -1) {
4fce284c
RB
349 /* return the next packets, if any */
350 timestamp= 0; ///< Should not be used if buf is NULL, but should be set to the timestamp of the packet returned....
1a45a9f4 351 rv= s->parse_packet(s->ic, s->dynamic_protocol_context,
7960e18f
RB
352 s->streams[s->prev_stream_id],
353 pkt, &timestamp, NULL, 0, flags);
4fce284c
RB
354 return rv;
355 }
356
357 if (len < 12)
358 return -1;
114732f4 359 rv = ff_rdt_parse_header(buf, len, &set_id, &seq_no, &stream_id, &is_keyframe, &timestamp);
4fce284c
RB
360 if (rv < 0)
361 return rv;
7960e18f
RB
362 if (is_keyframe &&
363 (set_id != s->prev_set_id || timestamp != s->prev_timestamp ||
364 stream_id != s->prev_stream_id)) {
a68d44ed 365 flags |= RTP_FLAG_KEY;
239dec21
RB
366 s->prev_set_id = set_id;
367 s->prev_timestamp = timestamp;
985b05d3 368 }
7960e18f 369 s->prev_stream_id = stream_id;
4fce284c
RB
370 buf += rv;
371 len -= rv;
4fce284c 372
7960e18f
RB
373 if (s->prev_stream_id >= s->n_streams) {
374 s->prev_stream_id = -1;
375 return -1;
376 }
377
1a45a9f4 378 rv = s->parse_packet(s->ic, s->dynamic_protocol_context,
7960e18f
RB
379 s->streams[s->prev_stream_id],
380 pkt, &timestamp, buf, len, flags);
4fce284c
RB
381
382 return rv;
383}
384
1256d16b 385void
ab63fb03 386ff_rdt_subscribe_rule (char *cmd, int size,
1256d16b
RB
387 int stream_nr, int rule_nr)
388{
1256d16b 389 av_strlcatf(cmd, size, "stream=%d;rule=%d,stream=%d;rule=%d",
ab63fb03
RB
390 stream_nr, rule_nr * 2, stream_nr, rule_nr * 2 + 1);
391}
392
ff13ba92
RB
393static unsigned char *
394rdt_parse_b64buf (unsigned int *target_len, const char *p)
395{
396 unsigned char *target;
397 int len = strlen(p);
398 if (*p == '\"') {
399 p++;
400 len -= 2; /* skip embracing " at start/end */
401 }
402 *target_len = len * 3 / 4;
403 target = av_mallocz(*target_len + FF_INPUT_BUFFER_PADDING_SIZE);
404 av_base64_decode(target, p, *target_len);
405 return target;
406}
407
408static int
7b2a0708
RB
409rdt_parse_sdp_line (AVFormatContext *s, int st_index,
410 PayloadContext *rdt, const char *line)
ff13ba92 411{
7b2a0708 412 AVStream *stream = s->streams[st_index];
ff13ba92
RB
413 const char *p = line;
414
415 if (av_strstart(p, "OpaqueData:buffer;", &p)) {
416 rdt->mlti_data = rdt_parse_b64buf(&rdt->mlti_data_size, p);
ff13ba92
RB
417 } else if (av_strstart(p, "StartTime:integer;", &p))
418 stream->first_dts = atoi(p);
7c68a177 419 else if (av_strstart(p, "ASMRuleBook:string;", &p)) {
0b9535b9 420 int n, first = -1;
7c68a177
RB
421
422 for (n = 0; n < s->nb_streams; n++)
423 if (s->streams[n]->priv_data == stream->priv_data) {
424 if (first == -1) first = n;
425 rdt->rmst[s->streams[n]->index] = ff_rm_alloc_rmstream();
426 rdt_load_mdpr(rdt, s->streams[n], (n - first) * 2);
427
428 if (s->streams[n]->codec->codec_id == CODEC_ID_AAC)
429 s->streams[n]->codec->frame_size = 1; // FIXME
430 }
431 }
ff13ba92
RB
432
433 return 0;
434}
435
530bca94
RB
436static void
437real_parse_asm_rule(AVStream *st, const char *p, const char *end)
438{
439 do {
440 /* can be either averagebandwidth= or AverageBandwidth= */
441 if (sscanf(p, " %*1[Aa]verage%*1[Bb]andwidth=%d", &st->codec->bit_rate) == 1)
442 break;
443 if (!(p = strchr(p, ',')) || p > end)
444 p = end;
445 p++;
446 } while (p < end);
447}
448
3ca45429
RB
449static AVStream *
450add_dstream(AVFormatContext *s, AVStream *orig_st)
451{
452 AVStream *st;
453
454 if (!(st = av_new_stream(s, 0)))
455 return NULL;
456 st->codec->codec_type = orig_st->codec->codec_type;
457 st->priv_data = orig_st->priv_data;
458 st->first_dts = orig_st->first_dts;
459
460 return st;
461}
462
463static void
464real_parse_asm_rulebook(AVFormatContext *s, AVStream *orig_st,
465 const char *p)
466{
467 const char *end;
468 int n_rules, odd = 0;
469 AVStream *st;
470
471 /**
472 * The ASMRuleBook contains a list of comma-separated strings per rule,
473 * and each rule is separated by a ;. The last one also has a ; at the
474 * end so we can use it as delimiter.
475 * Every rule occurs twice, once for when the RTSP packet header marker
476 * is set and once for if it isn't. We only read the first because we
477 * don't care much (that's what the "odd" variable is for).
478 * Each rule contains a set of one or more statements, optionally
479 * preceeded by a single condition. If there's a condition, the rule
480 * starts with a '#'. Multiple conditions are merged between brackets,
481 * so there are never multiple conditions spread out over separate
482 * statements. Generally, these conditions are bitrate limits (min/max)
483 * for multi-bitrate streams.
484 */
485 if (*p == '\"') p++;
486 for (n_rules = 0; s->nb_streams < MAX_STREAMS;) {
487 if (!(end = strchr(p, ';')))
488 break;
489 if (!odd && end != p) {
490 if (n_rules > 0)
491 st = add_dstream(s, orig_st);
492 else
493 st = orig_st;
530bca94 494 real_parse_asm_rule(st, p, end);
3ca45429
RB
495 n_rules++;
496 }
497 p = end + 1;
498 odd ^= 1;
499 }
500}
501
502void
503ff_real_parse_sdp_a_line (AVFormatContext *s, int stream_index,
504 const char *line)
505{
506 const char *p = line;
507
508 if (av_strstart(p, "ASMRuleBook:string;", &p))
509 real_parse_asm_rulebook(s, s->streams[stream_index], p);
510}
511
ed0aacc7 512static PayloadContext *
202a6697 513rdt_new_context (void)
ff13ba92 514{
ed0aacc7 515 PayloadContext *rdt = av_mallocz(sizeof(PayloadContext));
ff13ba92
RB
516
517 av_open_input_stream(&rdt->rmctx, NULL, "", &rdt_demuxer, NULL);
518
519 return rdt;
520}
521
522static void
202a6697 523rdt_free_context (PayloadContext *rdt)
ff13ba92 524{
7c68a177
RB
525 int i;
526
527 for (i = 0; i < MAX_STREAMS; i++)
528 if (rdt->rmst[i]) {
529 ff_rm_free_rmstream(rdt->rmst[i]);
530 av_freep(&rdt->rmst[i]);
531 }
ff13ba92
RB
532 if (rdt->rmctx)
533 av_close_input_stream(rdt->rmctx);
534 av_freep(&rdt->mlti_data);
535 av_free(rdt);
536}
537
538#define RDT_HANDLER(n, s, t) \
539static RTPDynamicProtocolHandler ff_rdt_ ## n ## _handler = { \
202a6697
CM
540 .enc_name = s, \
541 .codec_type = t, \
542 .codec_id = CODEC_ID_NONE, \
543 .parse_sdp_a_line = rdt_parse_sdp_line, \
544 .open = rdt_new_context, \
545 .close = rdt_free_context, \
546 .parse_packet = rdt_parse_packet \
ff13ba92
RB
547};
548
72415b2a
SS
549RDT_HANDLER(live_video, "x-pn-multirate-realvideo-live", AVMEDIA_TYPE_VIDEO);
550RDT_HANDLER(live_audio, "x-pn-multirate-realaudio-live", AVMEDIA_TYPE_AUDIO);
551RDT_HANDLER(video, "x-pn-realvideo", AVMEDIA_TYPE_VIDEO);
552RDT_HANDLER(audio, "x-pn-realaudio", AVMEDIA_TYPE_AUDIO);
ff13ba92
RB
553
554void av_register_rdt_dynamic_payload_handlers(void)
555{
556 ff_register_dynamic_payload_handler(&ff_rdt_video_handler);
557 ff_register_dynamic_payload_handler(&ff_rdt_audio_handler);
558 ff_register_dynamic_payload_handler(&ff_rdt_live_video_handler);
559 ff_register_dynamic_payload_handler(&ff_rdt_live_audio_handler);
560}