Libav 0.7.1
|
00001 /* 00002 * MMS protocol common definitions. 00003 * Copyright (c) 2006,2007 Ryan Martell 00004 * Copyright (c) 2007 Björn Axelsson 00005 * Copyright (c) 2010 Zhentan Feng <spyfeng at gmail dot com> 00006 * 00007 * This file is part of Libav. 00008 * 00009 * Libav is free software; you can redistribute it and/or 00010 * modify it under the terms of the GNU Lesser General Public 00011 * License as published by the Free Software Foundation; either 00012 * version 2.1 of the License, or (at your option) any later version. 00013 * 00014 * Libav is distributed in the hope that it will be useful, 00015 * but WITHOUT ANY WARRANTY; without even the implied warranty of 00016 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 00017 * Lesser General Public License for more details. 00018 * 00019 * You should have received a copy of the GNU Lesser General Public 00020 * License along with Libav; if not, write to the Free Software 00021 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 00022 */ 00023 #include "mms.h" 00024 #include "asf.h" 00025 #include "libavutil/intreadwrite.h" 00026 00027 #define MMS_MAX_STREAMS 256 00029 int ff_mms_read_header(MMSContext *mms, uint8_t *buf, const int size) 00030 { 00031 char *pos; 00032 int size_to_copy; 00033 int remaining_size = mms->asf_header_size - mms->asf_header_read_size; 00034 size_to_copy = FFMIN(size, remaining_size); 00035 pos = mms->asf_header + mms->asf_header_read_size; 00036 memcpy(buf, pos, size_to_copy); 00037 if (mms->asf_header_read_size == mms->asf_header_size) { 00038 av_freep(&mms->asf_header); // which contains asf header 00039 } 00040 mms->asf_header_read_size += size_to_copy; 00041 return size_to_copy; 00042 } 00043 00044 int ff_mms_read_data(MMSContext *mms, uint8_t *buf, const int size) 00045 { 00046 int read_size; 00047 read_size = FFMIN(size, mms->remaining_in_len); 00048 memcpy(buf, mms->read_in_ptr, read_size); 00049 mms->remaining_in_len -= read_size; 00050 mms->read_in_ptr += read_size; 00051 return read_size; 00052 } 00053 00054 int ff_mms_asf_header_parser(MMSContext *mms) 00055 { 00056 uint8_t *p = mms->asf_header; 00057 uint8_t *end; 00058 int flags, stream_id; 00059 mms->stream_num = 0; 00060 00061 if (mms->asf_header_size < sizeof(ff_asf_guid) * 2 + 22 || 00062 memcmp(p, ff_asf_header, sizeof(ff_asf_guid))) { 00063 av_log(NULL, AV_LOG_ERROR, 00064 "Corrupt stream (invalid ASF header, size=%d)\n", 00065 mms->asf_header_size); 00066 return AVERROR_INVALIDDATA; 00067 } 00068 00069 end = mms->asf_header + mms->asf_header_size; 00070 00071 p += sizeof(ff_asf_guid) + 14; 00072 while(end - p >= sizeof(ff_asf_guid) + 8) { 00073 uint64_t chunksize; 00074 if (!memcmp(p, ff_asf_data_header, sizeof(ff_asf_guid))) { 00075 chunksize = 50; // see Reference [2] section 5.1 00076 } else { 00077 chunksize = AV_RL64(p + sizeof(ff_asf_guid)); 00078 } 00079 if (!chunksize || chunksize > end - p) { 00080 av_log(NULL, AV_LOG_ERROR, 00081 "Corrupt stream (header chunksize %"PRId64" is invalid)\n", 00082 chunksize); 00083 return AVERROR_INVALIDDATA; 00084 } 00085 if (!memcmp(p, ff_asf_file_header, sizeof(ff_asf_guid))) { 00086 /* read packet size */ 00087 if (end - p > sizeof(ff_asf_guid) * 2 + 68) { 00088 mms->asf_packet_len = AV_RL32(p + sizeof(ff_asf_guid) * 2 + 64); 00089 if (mms->asf_packet_len <= 0 || mms->asf_packet_len > sizeof(mms->in_buffer)) { 00090 av_log(NULL, AV_LOG_ERROR, 00091 "Corrupt stream (too large pkt_len %d)\n", 00092 mms->asf_packet_len); 00093 return AVERROR_INVALIDDATA; 00094 } 00095 } 00096 } else if (!memcmp(p, ff_asf_stream_header, sizeof(ff_asf_guid))) { 00097 flags = AV_RL16(p + sizeof(ff_asf_guid)*3 + 24); 00098 stream_id = flags & 0x7F; 00099 //The second condition is for checking CS_PKT_STREAM_ID_REQUEST packet size, 00100 //we can calcuate the packet size by stream_num. 00101 //Please see function send_stream_selection_request(). 00102 if (mms->stream_num < MMS_MAX_STREAMS && 00103 46 + mms->stream_num * 6 < sizeof(mms->out_buffer)) { 00104 mms->streams = av_fast_realloc(mms->streams, 00105 &mms->nb_streams_allocated, 00106 (mms->stream_num + 1) * sizeof(MMSStream)); 00107 mms->streams[mms->stream_num].id = stream_id; 00108 mms->stream_num++; 00109 } else { 00110 av_log(NULL, AV_LOG_ERROR, 00111 "Corrupt stream (too many A/V streams)\n"); 00112 return AVERROR_INVALIDDATA; 00113 } 00114 } else if (!memcmp(p, ff_asf_ext_stream_header, sizeof(ff_asf_guid))) { 00115 if (end - p >= 88) { 00116 int stream_count = AV_RL16(p + 84), ext_len_count = AV_RL16(p + 86); 00117 uint64_t skip_bytes = 88; 00118 while (stream_count--) { 00119 if (end - p < skip_bytes + 4) { 00120 av_log(NULL, AV_LOG_ERROR, 00121 "Corrupt stream (next stream name length is not in the buffer)\n"); 00122 return AVERROR_INVALIDDATA; 00123 } 00124 skip_bytes += 4 + AV_RL16(p + skip_bytes + 2); 00125 } 00126 while (ext_len_count--) { 00127 if (end - p < skip_bytes + 22) { 00128 av_log(NULL, AV_LOG_ERROR, 00129 "Corrupt stream (next extension system info length is not in the buffer)\n"); 00130 return AVERROR_INVALIDDATA; 00131 } 00132 skip_bytes += 22 + AV_RL32(p + skip_bytes + 18); 00133 } 00134 if (end - p < skip_bytes) { 00135 av_log(NULL, AV_LOG_ERROR, 00136 "Corrupt stream (the last extension system info length is invalid)\n"); 00137 return AVERROR_INVALIDDATA; 00138 } 00139 if (chunksize - skip_bytes > 24) 00140 chunksize = skip_bytes; 00141 } 00142 } else if (!memcmp(p, ff_asf_head1_guid, sizeof(ff_asf_guid))) { 00143 chunksize = 46; // see references [2] section 3.4. This should be set 46. 00144 } 00145 p += chunksize; 00146 } 00147 00148 return 0; 00149 }