1 /*
2 * MMS protocol common definitions.
3 * Copyright (c) 2006,2007 Ryan Martell
4 * Copyright (c) 2007 Björn 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
ff_mms_read_header(MMSContext * mms,uint8_t * buf,const int size)29 int ff_mms_read_header(MMSContext *mms, uint8_t *buf, const int size)
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
ff_mms_read_data(MMSContext * mms,uint8_t * buf,const int size)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
ff_mms_asf_header_parser(MMSContext * mms)54 int ff_mms_asf_header_parser(MMSContext *mms)
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))) {
63 av_log(mms->mms_hd, AV_LOG_ERROR,
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) {
80 av_log(mms->mms_hd, AV_LOG_ERROR,
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)) {
90 av_log(mms->mms_hd, AV_LOG_ERROR,
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 if (end - p >= (sizeof(ff_asf_guid) * 3 + 26)) {
98 flags = AV_RL16(p + sizeof(ff_asf_guid)*3 + 24);
99 stream_id = flags & 0x7F;
100 //The second condition is for checking CS_PKT_STREAM_ID_REQUEST packet size,
101 //we can calculate the packet size by stream_num.
102 //Please see function send_stream_selection_request().
103 if (mms->stream_num < MMS_MAX_STREAMS &&
104 46 + mms->stream_num * 6 < sizeof(mms->out_buffer)) {
105 mms->streams = av_fast_realloc(mms->streams,
106 &mms->nb_streams_allocated,
107 (mms->stream_num + 1) * sizeof(MMSStream));
108 if (!mms->streams)
109 return AVERROR(ENOMEM);
110 mms->streams[mms->stream_num].id = stream_id;
111 mms->stream_num++;
112 } else {
113 av_log(mms->mms_hd, AV_LOG_ERROR,
114 "Corrupt stream (too many A/V streams)\n");
115 return AVERROR_INVALIDDATA;
116 }
117 }
118 } else if (!memcmp(p, ff_asf_ext_stream_header, sizeof(ff_asf_guid))) {
119 if (end - p >= 88) {
120 int stream_count = AV_RL16(p + 84), ext_len_count = AV_RL16(p + 86);
121 uint64_t skip_bytes = 88;
122 while (stream_count--) {
123 if (end - p < skip_bytes + 4) {
124 av_log(mms->mms_hd, AV_LOG_ERROR,
125 "Corrupt stream (next stream name length is not in the buffer)\n");
126 return AVERROR_INVALIDDATA;
127 }
128 skip_bytes += 4 + AV_RL16(p + skip_bytes + 2);
129 }
130 while (ext_len_count--) {
131 if (end - p < skip_bytes + 22) {
132 av_log(mms->mms_hd, AV_LOG_ERROR,
133 "Corrupt stream (next extension system info length is not in the buffer)\n");
134 return AVERROR_INVALIDDATA;
135 }
136 skip_bytes += 22 + AV_RL32(p + skip_bytes + 18);
137 }
138 if (end - p < skip_bytes) {
139 av_log(mms->mms_hd, AV_LOG_ERROR,
140 "Corrupt stream (the last extension system info length is invalid)\n");
141 return AVERROR_INVALIDDATA;
142 }
143 if (chunksize - skip_bytes > 24)
144 chunksize = skip_bytes;
145 }
146 } else if (!memcmp(p, ff_asf_head1_guid, sizeof(ff_asf_guid))) {
147 chunksize = 46; // see references [2] section 3.4. This should be set 46.
148 if (chunksize > end - p) {
149 av_log(mms->mms_hd, AV_LOG_ERROR,
150 "Corrupt stream (header chunksize %"PRId64" is invalid)\n",
151 chunksize);
152 return AVERROR_INVALIDDATA;
153 }
154 }
155 p += chunksize;
156 }
157
158 return 0;
159 }
160