Libav
rtpdec_asf.c
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1 /*
2  * Microsoft RTP/ASF support.
3  * Copyright (c) 2008 Ronald S. Bultje
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
28 #include "libavutil/base64.h"
29 #include "libavutil/avstring.h"
30 #include "libavutil/intreadwrite.h"
31 #include "rtp.h"
32 #include "rtpdec_formats.h"
33 #include "rtsp.h"
34 #include "asf.h"
35 #include "avio_internal.h"
36 #include "internal.h"
37 
45 static int rtp_asf_fix_header(uint8_t *buf, int len)
46 {
47  uint8_t *p = buf, *end = buf + len;
48 
49  if (len < sizeof(ff_asf_guid) * 2 + 22 ||
50  memcmp(p, ff_asf_header, sizeof(ff_asf_guid))) {
51  return -1;
52  }
53  p += sizeof(ff_asf_guid) + 14;
54  do {
55  uint64_t chunksize = AV_RL64(p + sizeof(ff_asf_guid));
56  if (memcmp(p, ff_asf_file_header, sizeof(ff_asf_guid))) {
57  if (chunksize > end - p)
58  return -1;
59  p += chunksize;
60  continue;
61  }
62 
63  /* skip most of the file header, to min_pktsize */
64  p += 6 * 8 + 3 * 4 + sizeof(ff_asf_guid) * 2;
65  if (p + 8 <= end && AV_RL32(p) == AV_RL32(p + 4)) {
66  /* and set that to zero */
67  AV_WL32(p, 0);
68  return 0;
69  }
70  break;
71  } while (end - p >= sizeof(ff_asf_guid) + 8);
72 
73  return -1;
74 }
75 
82 static int packetizer_read(void *opaque, uint8_t *buf, int buf_size)
83 {
84  return AVERROR(EAGAIN);
85 }
86 
87 static void init_packetizer(AVIOContext *pb, uint8_t *buf, int len)
88 {
89  ffio_init_context(pb, buf, len, 0, NULL, packetizer_read, NULL, NULL);
90 
91  /* this "fills" the buffer with its current content */
92  pb->pos = len;
93  pb->buf_end = buf + len;
94 }
95 
97 {
98  int ret = 0;
99  if (av_strstart(p, "pgmpu:data:application/vnd.ms.wms-hdr.asfv1;base64,", &p)) {
100  AVIOContext pb;
101  RTSPState *rt = s->priv_data;
102  AVDictionary *opts = NULL;
103  int len = strlen(p) * 6 / 8;
104  char *buf = av_mallocz(len);
105 
106  if (!buf)
107  return AVERROR(ENOMEM);
108  av_base64_decode(buf, p, len);
109 
110  if (rtp_asf_fix_header(buf, len) < 0)
111  av_log(s, AV_LOG_ERROR,
112  "Failed to fix invalid RTSP-MS/ASF min_pktsize\n");
113  init_packetizer(&pb, buf, len);
114  if (rt->asf_ctx) {
116  }
118  if (!rt->asf_ctx) {
119  av_free(buf);
120  return AVERROR(ENOMEM);
121  }
122  rt->asf_ctx->pb = &pb;
123  av_dict_set(&opts, "no_resync_search", "1", 0);
124  ret = avformat_open_input(&rt->asf_ctx, "", &ff_asf_demuxer, &opts);
125  av_dict_free(&opts);
126  if (ret < 0) {
127  av_free(buf);
128  return ret;
129  }
130  av_dict_copy(&s->metadata, rt->asf_ctx->metadata, 0);
131  rt->asf_pb_pos = avio_tell(&pb);
132  av_free(buf);
133  rt->asf_ctx->pb = NULL;
134  }
135  return ret;
136 }
137 
138 static int asfrtp_parse_sdp_line(AVFormatContext *s, int stream_index,
139  PayloadContext *asf, const char *line)
140 {
141  if (stream_index < 0)
142  return 0;
143  if (av_strstart(line, "stream:", &line)) {
144  RTSPState *rt = s->priv_data;
145 
146  s->streams[stream_index]->id = strtol(line, NULL, 10);
147 
148  if (rt->asf_ctx) {
149  int i;
150 
151  for (i = 0; i < rt->asf_ctx->nb_streams; i++) {
152  if (s->streams[stream_index]->id == rt->asf_ctx->streams[i]->id) {
153  *s->streams[stream_index]->codec =
154  *rt->asf_ctx->streams[i]->codec;
155  s->streams[stream_index]->need_parsing =
156  rt->asf_ctx->streams[i]->need_parsing;
157  rt->asf_ctx->streams[i]->codec->extradata_size = 0;
158  rt->asf_ctx->streams[i]->codec->extradata = NULL;
159  avpriv_set_pts_info(s->streams[stream_index], 32, 1, 1000);
160  }
161  }
162  }
163  }
164 
165  return 0;
166 }
167 
168 struct PayloadContext {
171 };
172 
179  AVStream *st, AVPacket *pkt,
180  uint32_t *timestamp,
181  const uint8_t *buf, int len, uint16_t seq,
182  int flags)
183 {
184  AVIOContext *pb = &asf->pb;
185  int res, mflags, len_off;
186  RTSPState *rt = s->priv_data;
187 
188  if (!rt->asf_ctx)
189  return -1;
190 
191  if (len > 0) {
192  int off, out_len = 0;
193 
194  if (len < 4)
195  return -1;
196 
197  av_freep(&asf->buf);
198 
199  ffio_init_context(pb, buf, len, 0, NULL, NULL, NULL, NULL);
200 
201  while (avio_tell(pb) + 4 < len) {
202  int start_off = avio_tell(pb);
203 
204  mflags = avio_r8(pb);
205  if (mflags & 0x80)
206  flags |= RTP_FLAG_KEY;
207  len_off = avio_rb24(pb);
208  if (mflags & 0x20)
209  avio_skip(pb, 4);
210  if (mflags & 0x10)
211  avio_skip(pb, 4);
212  if (mflags & 0x8)
213  avio_skip(pb, 4);
214  off = avio_tell(pb);
215 
216  if (!(mflags & 0x40)) {
223  if (asf->pktbuf && len_off != avio_tell(asf->pktbuf)) {
224  uint8_t *p;
225  avio_close_dyn_buf(asf->pktbuf, &p);
226  asf->pktbuf = NULL;
227  av_free(p);
228  }
229  if (!len_off && !asf->pktbuf &&
230  (res = avio_open_dyn_buf(&asf->pktbuf)) < 0)
231  return res;
232  if (!asf->pktbuf)
233  return AVERROR(EIO);
234 
235  avio_write(asf->pktbuf, buf + off, len - off);
236  avio_skip(pb, len - off);
237  if (!(flags & RTP_FLAG_MARKER))
238  return -1;
239  out_len = avio_close_dyn_buf(asf->pktbuf, &asf->buf);
240  asf->pktbuf = NULL;
241  } else {
250  int cur_len = start_off + len_off - off;
251  int prev_len = out_len;
252  out_len += cur_len;
253  if (FFMIN(cur_len, len - off) < 0)
254  return -1;
255  if ((res = av_reallocp(&asf->buf, out_len)) < 0)
256  return res;
257  memcpy(asf->buf + prev_len, buf + off,
258  FFMIN(cur_len, len - off));
259  avio_skip(pb, cur_len);
260  }
261  }
262 
263  init_packetizer(pb, asf->buf, out_len);
264  pb->pos += rt->asf_pb_pos;
265  pb->eof_reached = 0;
266  rt->asf_ctx->pb = pb;
267  }
268 
269  for (;;) {
270  int i;
271 
272  res = ff_read_packet(rt->asf_ctx, pkt);
273  rt->asf_pb_pos = avio_tell(pb);
274  if (res != 0)
275  break;
276  for (i = 0; i < s->nb_streams; i++) {
277  if (s->streams[i]->id == rt->asf_ctx->streams[pkt->stream_index]->id) {
278  pkt->stream_index = i;
279  return 1; // FIXME: return 0 if last packet
280  }
281  }
282  av_free_packet(pkt);
283  }
284 
285  return res == 1 ? -1 : res;
286 }
287 
289 {
290  return av_mallocz(sizeof(PayloadContext));
291 }
292 
294 {
295  if (asf->pktbuf) {
296  uint8_t *p = NULL;
297  avio_close_dyn_buf(asf->pktbuf, &p);
298  asf->pktbuf = NULL;
299  av_free(p);
300  }
301  av_freep(&asf->buf);
302  av_free(asf);
303 }
304 
305 #define RTP_ASF_HANDLER(n, s, t) \
306 RTPDynamicProtocolHandler ff_ms_rtp_ ## n ## _handler = { \
307  .enc_name = s, \
308  .codec_type = t, \
309  .codec_id = AV_CODEC_ID_NONE, \
310  .parse_sdp_a_line = asfrtp_parse_sdp_line, \
311  .alloc = asfrtp_new_context, \
312  .free = asfrtp_free_context, \
313  .parse_packet = asfrtp_parse_packet, \
314 }
315 
316 RTP_ASF_HANDLER(asf_pfv, "x-asf-pf", AVMEDIA_TYPE_VIDEO);
317 RTP_ASF_HANDLER(asf_pfa, "x-asf-pf", AVMEDIA_TYPE_AUDIO);
const ff_asf_guid ff_asf_header
Definition: asf.c:23
int ff_wms_parse_sdp_a_line(AVFormatContext *s, const char *p)
Parse a Windows Media Server-specific SDP line.
Definition: rtpdec_asf.c:96
Bytestream IO Context.
Definition: avio.h:68
void av_free_packet(AVPacket *pkt)
Free a packet.
Definition: avpacket.c:243
int avio_close_dyn_buf(AVIOContext *s, uint8_t **pbuffer)
Return the written size and a pointer to the buffer.
Definition: aviobuf.c:977
unsigned char * buf_end
End of the data, may be less than buffer+buffer_size if the read function returned less data than req...
Definition: avio.h:85
int avformat_open_input(AVFormatContext **ps, const char *filename, AVInputFormat *fmt, AVDictionary **options)
Open an input stream and read the header.
Definition: utils.c:247
void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: utils.c:2829
RTP/JPEG specific private data.
Definition: rdt.c:83
uint8_t * buf
the temporary storage buffer
Definition: rtpdec_asf.c:170
int avio_open_dyn_buf(AVIOContext **s)
Open a write only memory stream.
Definition: aviobuf.c:965
void av_freep(void *arg)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc() and set the pointer ...
Definition: mem.c:198
Format I/O context.
Definition: avformat.h:922
#define AV_RL64
Definition: intreadwrite.h:173
static int rtp_asf_fix_header(uint8_t *buf, int len)
From MSDN 2.2.1.4, we learn that ASF data packets over RTP should not contain any padding...
Definition: rtpdec_asf.c:45
uint8_t
enum AVStreamParseType need_parsing
Definition: avformat.h:867
int id
Format-specific stream ID.
Definition: avformat.h:706
#define AV_WL32(p, d)
Definition: intreadwrite.h:255
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1164
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:990
AVFormatContext * avformat_alloc_context(void)
Allocate an AVFormatContext.
Definition: options.c:98
int av_reallocp(void *ptr, size_t size)
Allocate or reallocate a block of memory.
Definition: mem.c:140
static int flags
Definition: log.c:44
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:219
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:165
void av_dict_copy(AVDictionary **dst, const AVDictionary *src, int flags)
Copy entries from one AVDictionary struct into another.
Definition: dict.c:184
Private data for the RTSP demuxer.
Definition: rtsp.h:217
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:123
AVDictionary * metadata
Metadata that applies to the whole file.
Definition: avformat.h:1130
void av_free(void *ptr)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc(). ...
Definition: mem.c:186
static int asfrtp_parse_packet(AVFormatContext *s, PayloadContext *asf, AVStream *st, AVPacket *pkt, uint32_t *timestamp, const uint8_t *buf, int len, uint16_t seq, int flags)
Definition: rtpdec_asf.c:178
#define RTP_FLAG_MARKER
RTP marker bit was set for this packet.
Definition: rtpdec.h:93
static int packetizer_read(void *opaque, uint8_t *buf, int buf_size)
The following code is basically a buffered AVIOContext, with the added benefit of returning -EAGAIN (...
Definition: rtpdec_asf.c:82
#define AVERROR(e)
Definition: error.h:43
void av_dict_free(AVDictionary **pm)
Free all the memory allocated for an AVDictionary struct and all keys and values. ...
Definition: dict.c:170
Definition: graph2dot.c:49
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:169
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:454
uint64_t asf_pb_pos
cache for position of the asf demuxer, since we load a new data packet in the bytecontext for each in...
Definition: rtsp.h:310
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:718
AVIOContext * pktbuf
Definition: rtpdec_asf.c:169
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:978
AVFormatContext * asf_ctx
The following are used for RTP/ASF streams.
Definition: rtsp.h:306
unsigned int avio_rb24(AVIOContext *s)
Definition: aviobuf.c:599
#define FFMIN(a, b)
Definition: common.h:57
static int asfrtp_parse_sdp_line(AVFormatContext *s, int stream_index, PayloadContext *asf, const char *line)
Definition: rtpdec_asf.c:138
static av_always_inline int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: avio.h:210
static void init_packetizer(AVIOContext *pb, uint8_t *buf, int len)
Definition: rtpdec_asf.c:87
#define AV_RL32
Definition: intreadwrite.h:146
int ff_read_packet(AVFormatContext *s, AVPacket *pkt)
Read a transport packet from a media file.
Definition: utils.c:372
uint8_t ff_asf_guid[16]
Definition: riff.h:70
Stream structure.
Definition: avformat.h:699
NULL
Definition: eval.c:55
const ff_asf_guid ff_asf_file_header
Definition: asf.c:27
#define RTP_FLAG_KEY
RTP packet contains a keyframe.
Definition: rtpdec.h:92
AVIOContext * pb
I/O context.
Definition: avformat.h:964
AVInputFormat ff_asf_demuxer
Definition: asfdec.c:1512
int extradata_size
Definition: avcodec.h:1165
int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags)
Set the given entry in *pm, overwriting an existing entry.
Definition: dict.c:68
static void asfrtp_free_context(PayloadContext *asf)
Definition: rtpdec_asf.c:293
static PayloadContext * asfrtp_new_context(void)
Definition: rtpdec_asf.c:288
int av_strstart(const char *str, const char *pfx, const char **ptr)
Return non-zero if pfx is a prefix of str.
Definition: avstring.c:32
#define RTP_ASF_HANDLER(n, s, t)
Definition: rtpdec_asf.c:305
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))
Definition: aviobuf.c:70
int64_t pos
position in the file of the current buffer
Definition: avio.h:94
void avformat_close_input(AVFormatContext **s)
Close an opened input AVFormatContext.
Definition: utils.c:2499
int eof_reached
true if eof reached
Definition: avio.h:96
int len
void * priv_data
Format private data.
Definition: avformat.h:950
int av_base64_decode(uint8_t *out, const char *in, int out_size)
Decode a base64-encoded string.
Definition: base64.c:45
int stream_index
Definition: avcodec.h:975
AVIOContext pb
Definition: rtpdec_asf.c:169
This structure stores compressed data.
Definition: avcodec.h:950
void * av_mallocz(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:205