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mms.c
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1 /*
2  * MMS protocol common definitions.
3  * Copyright (c) 2006,2007 Ryan Martell
4  * Copyright (c) 2007 Bj√∂rn Axelsson
5  * Copyright (c) 2010 Zhentan Feng <spyfeng at gmail dot com>
6  *
7  * This file is part of FFmpeg.
8  *
9  * FFmpeg is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU Lesser General Public
11  * License as published by the Free Software Foundation; either
12  * version 2.1 of the License, or (at your option) any later version.
13  *
14  * FFmpeg is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17  * Lesser General Public License for more details.
18  *
19  * You should have received a copy of the GNU Lesser General Public
20  * License along with FFmpeg; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22  */
23 #include "mms.h"
24 #include "asf.h"
25 #include "libavutil/intreadwrite.h"
26 
27 #define MMS_MAX_STREAMS 256 /**< arbitrary sanity check value */
28 
30 {
31  char *pos;
32  int size_to_copy;
33  int remaining_size = mms->asf_header_size - mms->asf_header_read_size;
34  size_to_copy = FFMIN(size, remaining_size);
35  pos = mms->asf_header + mms->asf_header_read_size;
36  memcpy(buf, pos, size_to_copy);
37  if (mms->asf_header_read_size == mms->asf_header_size) {
38  av_freep(&mms->asf_header); // which contains asf header
39  }
40  mms->asf_header_read_size += size_to_copy;
41  return size_to_copy;
42 }
43 
44 int ff_mms_read_data(MMSContext *mms, uint8_t *buf, const int size)
45 {
46  int read_size;
47  read_size = FFMIN(size, mms->remaining_in_len);
48  memcpy(buf, mms->read_in_ptr, read_size);
49  mms->remaining_in_len -= read_size;
50  mms->read_in_ptr += read_size;
51  return read_size;
52 }
53 
55 {
56  uint8_t *p = mms->asf_header;
57  uint8_t *end;
58  int flags, stream_id;
59  mms->stream_num = 0;
60 
61  if (mms->asf_header_size < sizeof(ff_asf_guid) * 2 + 22 ||
62  memcmp(p, ff_asf_header, sizeof(ff_asf_guid))) {
64  "Corrupt stream (invalid ASF header, size=%d)\n",
65  mms->asf_header_size);
66  return AVERROR_INVALIDDATA;
67  }
68 
69  end = mms->asf_header + mms->asf_header_size;
70 
71  p += sizeof(ff_asf_guid) + 14;
72  while(end - p >= sizeof(ff_asf_guid) + 8) {
73  uint64_t chunksize;
74  if (!memcmp(p, ff_asf_data_header, sizeof(ff_asf_guid))) {
75  chunksize = 50; // see Reference [2] section 5.1
76  } else {
77  chunksize = AV_RL64(p + sizeof(ff_asf_guid));
78  }
79  if (!chunksize || chunksize > end - p) {
81  "Corrupt stream (header chunksize %"PRId64" is invalid)\n",
82  chunksize);
83  return AVERROR_INVALIDDATA;
84  }
85  if (!memcmp(p, ff_asf_file_header, sizeof(ff_asf_guid))) {
86  /* read packet size */
87  if (end - p > sizeof(ff_asf_guid) * 2 + 68) {
88  mms->asf_packet_len = AV_RL32(p + sizeof(ff_asf_guid) * 2 + 64);
89  if (mms->asf_packet_len <= 0 || mms->asf_packet_len > sizeof(mms->in_buffer)) {
91  "Corrupt stream (too large pkt_len %d)\n",
92  mms->asf_packet_len);
93  return AVERROR_INVALIDDATA;
94  }
95  }
96  } else if (!memcmp(p, ff_asf_stream_header, sizeof(ff_asf_guid))) {
97  flags = AV_RL16(p + sizeof(ff_asf_guid)*3 + 24);
98  stream_id = flags & 0x7F;
99  //The second condition is for checking CS_PKT_STREAM_ID_REQUEST packet size,
100  //we can calcuate the packet size by stream_num.
101  //Please see function send_stream_selection_request().
102  if (mms->stream_num < MMS_MAX_STREAMS &&
103  46 + mms->stream_num * 6 < sizeof(mms->out_buffer)) {
104  mms->streams = av_fast_realloc(mms->streams,
105  &mms->nb_streams_allocated,
106  (mms->stream_num + 1) * sizeof(MMSStream));
107  if (!mms->streams)
108  return AVERROR(ENOMEM);
109  mms->streams[mms->stream_num].id = stream_id;
110  mms->stream_num++;
111  } else {
113  "Corrupt stream (too many A/V streams)\n");
114  return AVERROR_INVALIDDATA;
115  }
116  } else if (!memcmp(p, ff_asf_ext_stream_header, sizeof(ff_asf_guid))) {
117  if (end - p >= 88) {
118  int stream_count = AV_RL16(p + 84), ext_len_count = AV_RL16(p + 86);
119  uint64_t skip_bytes = 88;
120  while (stream_count--) {
121  if (end - p < skip_bytes + 4) {
123  "Corrupt stream (next stream name length is not in the buffer)\n");
124  return AVERROR_INVALIDDATA;
125  }
126  skip_bytes += 4 + AV_RL16(p + skip_bytes + 2);
127  }
128  while (ext_len_count--) {
129  if (end - p < skip_bytes + 22) {
131  "Corrupt stream (next extension system info length is not in the buffer)\n");
132  return AVERROR_INVALIDDATA;
133  }
134  skip_bytes += 22 + AV_RL32(p + skip_bytes + 18);
135  }
136  if (end - p < skip_bytes) {
138  "Corrupt stream (the last extension system info length is invalid)\n");
139  return AVERROR_INVALIDDATA;
140  }
141  if (chunksize - skip_bytes > 24)
142  chunksize = skip_bytes;
143  }
144  } else if (!memcmp(p, ff_asf_head1_guid, sizeof(ff_asf_guid))) {
145  chunksize = 46; // see references [2] section 3.4. This should be set 46.
146  }
147  p += chunksize;
148  }
149 
150  return 0;
151 }
const ff_asf_guid ff_asf_header
Definition: asf.c:23
#define NULL
Definition: coverity.c:32
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
unsigned int nb_streams_allocated
allocated size of streams
Definition: mms.h:57
uint8_t * read_in_ptr
Pointer for reading from incoming buffer.
Definition: mms.h:43
Definition: mms.h:30
int ff_mms_read_header(MMSContext *mms, uint8_t *buf, const int size)
Definition: mms.c:29
int stream_num
stream numbers.
Definition: mms.h:56
#define MMS_MAX_STREAMS
arbitrary sanity check value
Definition: mms.c:27
const ff_asf_guid ff_asf_ext_stream_header
Definition: asf.c:35
uint64_t_TMPL AV_RL64
Definition: bytestream.h:87
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:87
uint8_t * asf_header
Internal handling of the ASF header.
Definition: mms.h:49
const ff_asf_guid ff_asf_data_header
Definition: asf.c:80
uint8_t
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
int ff_mms_read_data(MMSContext *mms, uint8_t *buf, const int size)
Definition: mms.c:44
int asf_packet_len
Definition: mms.h:52
ptrdiff_t size
Definition: opengl_enc.c:101
static av_unused const uint8_t * skip_bytes(CABACContext *c, int n)
Skip n bytes and reset the decoder.
#define av_log(a,...)
uint8_t in_buffer[65536]
Buffer for incoming packets.
Definition: mms.h:42
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
const ff_asf_guid ff_asf_head1_guid
Definition: asf.c:84
void * av_fast_realloc(void *ptr, unsigned int *size, size_t min_size)
Reallocate the given block if it is not large enough, otherwise do nothing.
Definition: mem.c:480
#define AVERROR(e)
Definition: error.h:43
int asf_header_read_size
Definition: mms.h:53
#define FFMIN(a, b)
Definition: common.h:66
uint8_t ff_asf_guid[16]
Definition: riff.h:84
uint8_t out_buffer[512]
Buffer for outgoing packet.
Definition: mms.h:37
int remaining_in_len
Reading length from incoming buffer.
Definition: mms.h:44
const ff_asf_guid ff_asf_file_header
Definition: asf.c:27
void * buf
Definition: avisynth_c.h:553
const ff_asf_guid ff_asf_stream_header
Definition: asf.c:31
int asf_header_size
Size of stored ASF header.
Definition: mms.h:50
static int flags
Definition: cpu.c:47
Definition: mms.h:26
int id
Definition: mms.h:27
MMSStream * streams
Definition: mms.h:32
#define av_freep(p)
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
int ff_mms_asf_header_parser(MMSContext *mms)
Definition: mms.c:54