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 /**
23 * @file
24 * @brief Realmedia RTSP protocol (RDT) support
25 * @author Ronald S. Bultje <rbultje@ronald.bitfreak.net>
26 */
27
38
41 /** Each RDT stream-set (represented by one RTSPStream) can contain
42 * multiple streams (of the same content, but with possibly different
43 * codecs/bitrates). Each such stream is represented by one AVStream
44 * in the AVFormatContext, and this variable points to the offset in
45 * that array such that the first is the first stream of this set. */
47 int n_streams;
/**< streams with identifical content in this set */
52 };
53
57 {
59 if (!s)
61
64 do {
73
75 }
76
77 void
79 {
81 }
82
91 };
92
93 void
95 const char *challenge)
96 {
97 int ch_len = strlen (challenge), i;
98 unsigned char zres[16],
99 buf[64] = { 0xa1, 0xe9, 0x14, 0x9d, 0x0e, 0x6b, 0x3b, 0x59 };
100 #define XOR_TABLE_SIZE 37
102 0x05, 0x18, 0x74, 0xd0, 0x0d, 0x09, 0x02, 0x53,
103 0xc0, 0x01, 0x05, 0x05, 0x67, 0x03, 0x19, 0x70,
104 0x08, 0x27, 0x66, 0x10, 0x10, 0x72, 0x08, 0x09,
105 0x63, 0x11, 0x03, 0x71, 0x08, 0x08, 0x70, 0x02,
106 0x10, 0x57, 0x05, 0x18, 0x54 };
107
108 /* some (length) checks */
109 if (ch_len == 40) /* what a hack... */
110 ch_len = 32;
111 else if (ch_len > 56)
112 ch_len = 56;
113 memcpy(buf + 8, challenge, ch_len);
114
115 /* xor challenge bytewise with xor_table */
117 buf[8 + i] ^= xor_table[i];
118
121
122 /* add tail */
123 strcpy (response + 32, "01d0a8e3");
124
125 /* calculate checksum */
126 for (i = 0; i < 8; i++)
127 chksum[i] = response[i * 4];
128 chksum[8] = 0;
129 }
130
131 static int
133 {
137
138 /**
139 * Layout of the MLTI chunk:
140 * 4: MLTI
141 * 2: number of streams
142 * Then for each stream ([number_of_streams] times):
143 * 2: mdpr index
144 * 2: number of mdpr chunks
145 * Then for each mdpr chunk ([number_of_mdpr_chunks] times):
146 * 4: size
147 * [size]: data
148 * we skip MDPR chunks until we reach the one of the stream
149 * we're interested in, and forward that ([size]+[data]) to
150 * the RM demuxer to parse the stream-specific header data.
151 */
153 return -1;
157 if (tag ==
MKTAG(
'M',
'L',
'T',
'I')) {
158 int num, chunk_nr;
159
160 /* read index of MDPR chunk numbers */
162 if (rule_nr < 0 || rule_nr >= num)
163 return -1;
167
168 /* read MDPR chunks */
170 if (chunk_nr >= num)
171 return -1;
172 while (chunk_nr--)
175 } else {
178 }
180 return -1;
181
182 return 0;
183 }
184
185 /**
186 * Actual data handling.
187 */
188
189 int
191 int *pset_id, int *pseq_no, int *pstream_id,
192 int *pis_keyframe, uint32_t *ptimestamp)
193 {
195 int consumed = 0, set_id, seq_no, stream_id,
is_keyframe,
196 len_included, need_reliable;
197 uint32_t timestamp;
198
199 /* skip status packets */
200 while (len >= 5 && buf[1] == 0xFF /* status packet */) {
201 int pkt_len;
202
203 if (!(buf[0] & 0x80))
204 return -1; /* not followed by a data packet */
205
207 buf += pkt_len;
208 len -= pkt_len;
209 consumed += pkt_len;
210 }
211 if (len < 16)
212 return -1;
213 /**
214 * Layout of the header (in bits):
215 * 1: len_included
216 * Flag indicating whether this header includes a length field;
217 * this can be used to concatenate multiple RDT packets in a
218 * single UDP/TCP data frame and is used to precede RDT data
219 * by stream status packets
220 * 1: need_reliable
221 * Flag indicating whether this header includes a "reliable
222 * sequence number"; these are apparently sequence numbers of
223 * data packets alone. For data packets, this flag is always
224 * set, according to the Real documentation [1]
225 * 5: set_id
226 * ID of a set of streams of identical content, possibly with
227 * different codecs or bitrates
228 * 1: is_reliable
229 * Flag set for certain streams deemed less tolerable for packet
230 * loss
231 * 16: seq_no
232 * Packet sequence number; if >=0xFF00, this is a non-data packet
233 * containing stream status info, the second byte indicates the
234 * type of status packet (see wireshark docs / source code [2])
235 * if (len_included) {
236 * 16: packet_len
237 * } else {
238 * packet_len = remainder of UDP/TCP frame
239 * }
240 * 1: is_back_to_back
241 * Back-to-Back flag; used for timing, set for one in every 10
242 * packets, according to the Real documentation [1]
243 * 1: is_slow_data
244 * Slow-data flag; currently unused, according to Real docs [1]
245 * 5: stream_id
246 * ID of the stream within this particular set of streams
247 * 1: is_no_keyframe
248 * Non-keyframe flag (unset if packet belongs to a keyframe)
249 * 32: timestamp (PTS)
250 * if (set_id == 0x1F) {
251 * 16: set_id (extended set-of-streams ID; see set_id)
252 * }
253 * if (need_reliable) {
254 * 16: reliable_seq_no
255 * Reliable sequence number (see need_reliable)
256 * }
257 * if (stream_id == 0x3F) {
258 * 16: stream_id (extended stream ID; see stream_id)
259 * }
260 * [1] https://protocol.helixcommunity.org/files/2005/devdocs/RDT_Feature_Level_20.txt
261 * [2] http://www.wireshark.org/docs/dfref/r/rdt.html and
262 * http://anonsvn.wireshark.org/viewvc/trunk/epan/dissectors/packet-rdt.c
263 */
270 if (len_included)
276 if (set_id == 0x1f)
278 if (need_reliable)
280 if (stream_id == 0x1f)
282
283 if (pset_id) *pset_id = set_id;
284 if (pseq_no) *pseq_no = seq_no;
285 if (pstream_id) *pstream_id = stream_id;
287 if (ptimestamp) *ptimestamp = timestamp;
288
290 }
291
292 /**< return 0 on packet, no more left, 1 on packet, 1 on partial packet... */
293 static int
297 {
298 int seq = 1, res;
300
302 int pos, rmflags;
303
307 &seq, rmflags, *timestamp);
309 if (res < 0)
310 return res;
311 if (res > 0) {
313 memcpy (rdt->
buffer, buf + pos, len - pos);
316 }
317 goto get_cache;
318 }
319 } else {
320 get_cache:
327 }
329 pkt->
pts = *timestamp;
330
332 }
333
334 int
337 {
340 uint32_t timestamp;
341 int rv= 0;
342
344 return -1;
345
347 /* return the next packets, if any */
348 timestamp= 0; ///< Should not be used if buf is NULL, but should be set to the timestamp of the packet returned....
351 pkt, ×tamp,
NULL, 0, 0, flags);
352 return rv;
353 }
354
355 if (len < 12)
356 return -1;
357 rv =
ff_rdt_parse_header(buf, len, &set_id, &seq_no, &stream_id, &is_keyframe, ×tamp);
358 if (rv < 0)
359 return rv;
360 if (is_keyframe &&
366 }
368 buf += rv;
369 len -= rv;
370
373 return -1;
374 }
375
378 pkt, ×tamp, buf, len, 0, flags);
379
380 return rv;
381 }
382
383 void
385 int stream_nr, int rule_nr)
386 {
387 av_strlcatf(cmd, size,
"stream=%d;rule=%d,stream=%d;rule=%d",
388 stream_nr, rule_nr * 2, stream_nr, rule_nr * 2 + 1);
389 }
390
391 static unsigned char *
393 {
394 unsigned char *target;
396 if (*p == '\"') {
397 p++;
398 len -= 2; /* skip embracing " at start/end */
399 }
400 *target_len = len * 3 / 4;
402 if (!target)
405 return target;
406 }
407
408 static int
411 {
413 const char *p = line;
414
417 }
else if (
av_strstart(p,
"StartTime:integer;", &p))
419 else if (
av_strstart(p,
"ASMRuleBook:string;", &p)) {
421
425 if (first == -1) first =
n;
428 count *
sizeof(*rdt->
rmst))) < 0) {
430 return err;
431 }
435 }
440 }
441 }
442
443 return 0;
444 }
445
446 static void
448 {
449 do {
450 /* can be either averagebandwidth= or AverageBandwidth= */
451 if (sscanf(p,
" %*1[Aa]verage%*1[Bb]andwidth=%"SCNd64, &st->
codec->
bit_rate) == 1)
452 break;
453 if (!(p = strchr(p, ',')) || p > end)
455 p++;
456 } while (p < end);
457 }
458
461 {
463
466 st->
id = orig_st->
id;
469
470 return st;
471 }
472
473 static void
475 const char *p)
476 {
478 int n_rules = 0, odd = 0;
480
481 /**
482 * The ASMRuleBook contains a list of comma-separated strings per rule,
483 * and each rule is separated by a ;. The last one also has a ; at the
484 * end so we can use it as delimiter.
485 * Every rule occurs twice, once for when the RTSP packet header marker
486 * is set and once for if it isn't. We only read the first because we
487 * don't care much (that's what the "odd" variable is for).
488 * Each rule contains a set of one or more statements, optionally
489 * preceded by a single condition. If there's a condition, the rule
490 * starts with a '#'. Multiple conditions are merged between brackets,
491 * so there are never multiple conditions spread out over separate
492 * statements. Generally, these conditions are bitrate limits (min/max)
493 * for multi-bitrate streams.
494 */
495 if (*p == '\"') p++;
496 while (1) {
497 if (!(end = strchr(p, ';')))
498 break;
499 if (!odd && end != p) {
500 if (n_rules > 0)
502 else
503 st = orig_st;
504 if (!st)
505 break;
507 n_rules++;
508 }
509 p = end + 1;
510 odd ^= 1;
511 }
512 }
513
514 void
517 {
518 const char *p = line;
519
522 }
523
524
525
527 {
528 int ret;
529
533
535 return ret;
536
538 }
539
540 static void
542 {
543 int i;
544
545 for (i = 0; i < rdt->
nb_rmst; i++)
549 }
554 }
555
556 #define RDT_HANDLER(n, s, t) \
557 static RTPDynamicProtocolHandler rdt_ ## n ## _handler = { \
558 .enc_name = s, \
559 .codec_type = t, \
560 .codec_id = AV_CODEC_ID_NONE, \
561 .priv_data_size = sizeof(PayloadContext), \
562 .init = rdt_init, \
563 .parse_sdp_a_line = rdt_parse_sdp_line, \
564 .close = rdt_close_context, \
565 .parse_packet = rdt_parse_packet \
566 }
567
572
574 {
579 }
static void real_parse_asm_rulebook(AVFormatContext *s, AVStream *orig_st, const char *p)
int64_t first_dts
Timestamp corresponding to the last dts sync point.
int n_streams
streams with identifical content in this set
#define RTP_MAX_PACKET_LENGTH
static int is_keyframe(NalUnitType naltype)
RMStream * ff_rm_alloc_rmstream(void)
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
int64_t bit_rate
the average bitrate
RTP/JPEG specific private data.
int ff_rdt_parse_packet(RDTDemuxContext *s, AVPacket *pkt, uint8_t **bufptr, int len)
Parse RDT-style packet data (header + media data).
int index
stream index in AVFormatContext
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
unsigned int avio_rb16(AVIOContext *s)
void ff_rdt_subscribe_rule(char *cmd, int size, int stream_nr, int rule_nr)
Add subscription information to Subscribe parameter string.
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_WB24 unsigned int_TMPL AV_RB16
static int rdt_parse_sdp_line(AVFormatContext *s, int st_index, PayloadContext *rdt, const char *line)
unsigned int avio_rb32(AVIOContext *s)
static av_cold int end(AVCodecContext *avctx)
int id
Format-specific stream ID.
int ff_rm_parse_packet(AVFormatContext *s, AVIOContext *pb, AVStream *st, RMStream *rst, int len, AVPacket *pkt, int *seq, int flags, int64_t ts)
Parse one rm-stream packet from the input bytestream.
static void handler(vbi_event *ev, void *user_data)
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
AVStream ** streams
A list of all streams in the file.
AVFormatContext * avformat_alloc_context(void)
Allocate an AVFormatContext.
AVStream ** streams
Each RDT stream-set (represented by one RTSPStream) can contain multiple streams (of the same content...
static int get_bits_count(const GetBitContext *s)
bitstream reader API header.
static int rdt_load_mdpr(PayloadContext *rdt, AVStream *st, int rule_nr)
void av_md5_sum(uint8_t *dst, const uint8_t *src, const int len)
Hash an array of data.
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
static void rdt_close_context(PayloadContext *rdt)
void ff_register_rdt_dynamic_payload_handlers(void)
Register RDT-related dynamic payload handlers with our cache.
void ff_rdt_parse_close(RDTDemuxContext *s)
AVIOContext * avio_alloc_context(unsigned char *buffer, int buffer_size, int write_flag, void *opaque, int(*read_packet)(void *opaque, uint8_t *buf, int buf_size), int(*write_packet)(void *opaque, uint8_t *buf, int buf_size), int64_t(*seek)(void *opaque, int64_t offset, int whence))
Allocate and initialize an AVIOContext for buffered I/O.
int ff_rm_read_mdpr_codecdata(AVFormatContext *s, AVIOContext *pb, AVStream *st, RMStream *rst, unsigned int codec_data_size, const uint8_t *mime)
Read the MDPR chunk, which contains stream-specific codec initialization parameters.
int audio_pkt_cnt
remaining audio packets in rmdec
unsigned int avio_rl32(AVIOContext *s)
char buffer[RTP_MAX_PACKET_LENGTH+AV_INPUT_BUFFER_PADDING_SIZE]
DynamicPayloadPacketHandlerProc parse_packet
Parse handler for this dynamic packet.
AVFormatContext * ic
the containing (RTSP) demux context
AVCodecContext * codec
Codec context associated with this stream.
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
static av_cold int rdt_init(AVFormatContext *s, int st_index, PayloadContext *rdt)
int(* DynamicPayloadPacketHandlerProc)(AVFormatContext *ctx, PayloadContext *s, AVStream *st, AVPacket *pkt, uint32_t *timestamp, const uint8_t *buf, int len, uint16_t seq, int flags)
Packet parsing for "private" payloads in the RTP specs.
int ff_rdt_parse_header(const uint8_t *buf, int len, int *pset_id, int *pseq_no, int *pstream_id, int *pis_keyframe, uint32_t *ptimestamp)
Actual data handling.
DynamicPayloadPacketHandlerProc parse_packet
enum AVMediaType codec_type
int ff_rm_retrieve_cache(AVFormatContext *s, AVIOContext *pb, AVStream *st, RMStream *rst, AVPacket *pkt)
Retrieve one cached packet from the rm-context.
#define RTP_FLAG_KEY
RTP packet contains a keyframe.
AVIOContext * pb
I/O context.
static int rdt_parse_packet(AVFormatContext *ctx, PayloadContext *rdt, AVStream *st, AVPacket *pkt, uint32_t *timestamp, const uint8_t *buf, int len, uint16_t rtp_seq, int flags)
void ff_register_dynamic_payload_handler(RTPDynamicProtocolHandler *handler)
RDTDemuxContext * ff_rdt_parse_open(AVFormatContext *ic, int first_stream_of_set_idx, void *priv_data, RTPDynamicProtocolHandler *handler)
Allocate and init the RDT parsing context.
static unsigned char * rdt_parse_b64buf(unsigned int *target_len, const char *p)
static unsigned int get_bits1(GetBitContext *s)
static void skip_bits(GetBitContext *s, int n)
void ff_real_parse_sdp_a_line(AVFormatContext *s, int stream_index, const char *line)
Parse a server-related SDP line.
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
size_t av_strlcatf(char *dst, size_t size, const char *fmt,...)
void * dynamic_protocol_context
static unsigned int get_bits_long(GetBitContext *s, int n)
Read 0-32 bits.
int av_strstart(const char *str, const char *pfx, const char **ptr)
Return non-zero if pfx is a prefix of str.
int ffio_init_context(AVIOContext *s, unsigned char *buffer, int buffer_size, int write_flag, void *opaque, int(*read_packet)(void *opaque, uint8_t *buf, int buf_size), int(*write_packet)(void *opaque, uint8_t *buf, int buf_size), int64_t(*seek)(void *opaque, int64_t offset, int whence))
int av_reallocp(void *ptr, size_t size)
Allocate or reallocate a block of memory.
static void real_parse_asm_rule(AVStream *st, const char *p, const char *end)
void ff_rdt_calc_response_and_checksum(char response[41], char chksum[9], const char *challenge)
Calculate the response (RealChallenge2 in the RTSP header) to the challenge (RealChallenge1 in the RT...
void ff_rm_free_rmstream(RMStream *rms)
void avformat_close_input(AVFormatContext **s)
Close an opened input AVFormatContext.
#define AV_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding...
static AVStream * add_dstream(AVFormatContext *s, AVStream *orig_st)
unsigned int mlti_data_size
int av_base64_decode(uint8_t *out, const char *in_str, int out_size)
Decode a base64-encoded string.
int avformat_open_input(AVFormatContext **ps, const char *url, AVInputFormat *fmt, AVDictionary **options)
Open an input stream and read the header.
AVInputFormat ff_rdt_demuxer
#define MKTAG(a, b, c, d)
#define RDT_HANDLER(n, s, t)
This structure stores compressed data.
void * av_mallocz(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...