| /* |
| * MMS protocol common definitions. |
| * Copyright (c) 2006,2007 Ryan Martell |
| * Copyright (c) 2007 Björn Axelsson |
| * Copyright (c) 2010 Zhentan Feng <spyfeng at gmail dot com> |
| * |
| * This file is part of FFmpeg. |
| * |
| * FFmpeg is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2.1 of the License, or (at your option) any later version. |
| * |
| * FFmpeg is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with FFmpeg; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| #include "mms.h" |
| #include "asf.h" |
| #include "libavutil/intreadwrite.h" |
| |
| #define MMS_MAX_STREAMS 256 /**< arbitrary sanity check value */ |
| |
| int ff_mms_read_header(MMSContext *mms, uint8_t *buf, const int size) |
| { |
| char *pos; |
| int size_to_copy; |
| int remaining_size = mms->asf_header_size - mms->asf_header_read_size; |
| size_to_copy = FFMIN(size, remaining_size); |
| pos = mms->asf_header + mms->asf_header_read_size; |
| memcpy(buf, pos, size_to_copy); |
| if (mms->asf_header_read_size == mms->asf_header_size) { |
| av_freep(&mms->asf_header); // which contains asf header |
| } |
| mms->asf_header_read_size += size_to_copy; |
| return size_to_copy; |
| } |
| |
| int ff_mms_read_data(MMSContext *mms, uint8_t *buf, const int size) |
| { |
| int read_size; |
| read_size = FFMIN(size, mms->remaining_in_len); |
| memcpy(buf, mms->read_in_ptr, read_size); |
| mms->remaining_in_len -= read_size; |
| mms->read_in_ptr += read_size; |
| return read_size; |
| } |
| |
| int ff_mms_asf_header_parser(MMSContext *mms) |
| { |
| uint8_t *p = mms->asf_header; |
| uint8_t *end; |
| int flags, stream_id; |
| mms->stream_num = 0; |
| |
| if (mms->asf_header_size < sizeof(ff_asf_guid) * 2 + 22 || |
| memcmp(p, ff_asf_header, sizeof(ff_asf_guid))) { |
| av_log(NULL, AV_LOG_ERROR, |
| "Corrupt stream (invalid ASF header, size=%d)\n", |
| mms->asf_header_size); |
| return AVERROR_INVALIDDATA; |
| } |
| |
| end = mms->asf_header + mms->asf_header_size; |
| |
| p += sizeof(ff_asf_guid) + 14; |
| while(end - p >= sizeof(ff_asf_guid) + 8) { |
| uint64_t chunksize; |
| if (!memcmp(p, ff_asf_data_header, sizeof(ff_asf_guid))) { |
| chunksize = 50; // see Reference [2] section 5.1 |
| } else { |
| chunksize = AV_RL64(p + sizeof(ff_asf_guid)); |
| } |
| if (!chunksize || chunksize > end - p) { |
| av_log(NULL, AV_LOG_ERROR, |
| "Corrupt stream (header chunksize %"PRId64" is invalid)\n", |
| chunksize); |
| return AVERROR_INVALIDDATA; |
| } |
| if (!memcmp(p, ff_asf_file_header, sizeof(ff_asf_guid))) { |
| /* read packet size */ |
| if (end - p > sizeof(ff_asf_guid) * 2 + 68) { |
| mms->asf_packet_len = AV_RL32(p + sizeof(ff_asf_guid) * 2 + 64); |
| if (mms->asf_packet_len <= 0 || mms->asf_packet_len > sizeof(mms->in_buffer)) { |
| av_log(NULL, AV_LOG_ERROR, |
| "Corrupt stream (too large pkt_len %d)\n", |
| mms->asf_packet_len); |
| return AVERROR_INVALIDDATA; |
| } |
| } |
| } else if (!memcmp(p, ff_asf_stream_header, sizeof(ff_asf_guid))) { |
| flags = AV_RL16(p + sizeof(ff_asf_guid)*3 + 24); |
| stream_id = flags & 0x7F; |
| //The second condition is for checking CS_PKT_STREAM_ID_REQUEST packet size, |
| //we can calcuate the packet size by stream_num. |
| //Please see function send_stream_selection_request(). |
| if (mms->stream_num < MMS_MAX_STREAMS && |
| 46 + mms->stream_num * 6 < sizeof(mms->out_buffer)) { |
| mms->streams = av_fast_realloc(mms->streams, |
| &mms->nb_streams_allocated, |
| (mms->stream_num + 1) * sizeof(MMSStream)); |
| mms->streams[mms->stream_num].id = stream_id; |
| mms->stream_num++; |
| } else { |
| av_log(NULL, AV_LOG_ERROR, |
| "Corrupt stream (too many A/V streams)\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| } else if (!memcmp(p, ff_asf_ext_stream_header, sizeof(ff_asf_guid))) { |
| if (end - p >= 88) { |
| int stream_count = AV_RL16(p + 84), ext_len_count = AV_RL16(p + 86); |
| uint64_t skip_bytes = 88; |
| while (stream_count--) { |
| if (end - p < skip_bytes + 4) { |
| av_log(NULL, AV_LOG_ERROR, |
| "Corrupt stream (next stream name length is not in the buffer)\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| skip_bytes += 4 + AV_RL16(p + skip_bytes + 2); |
| } |
| while (ext_len_count--) { |
| if (end - p < skip_bytes + 22) { |
| av_log(NULL, AV_LOG_ERROR, |
| "Corrupt stream (next extension system info length is not in the buffer)\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| skip_bytes += 22 + AV_RL32(p + skip_bytes + 18); |
| } |
| if (end - p < skip_bytes) { |
| av_log(NULL, AV_LOG_ERROR, |
| "Corrupt stream (the last extension system info length is invalid)\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| if (chunksize - skip_bytes > 24) |
| chunksize = skip_bytes; |
| } |
| } else if (!memcmp(p, ff_asf_head1_guid, sizeof(ff_asf_guid))) { |
| chunksize = 46; // see references [2] section 3.4. This should be set 46. |
| } |
| p += chunksize; |
| } |
| |
| return 0; |
| } |