ffmpeg/libavcodec/aac_ac3_parser.h
James Almer 4c35bb53f9 avcodec/ac3_parser: improve false positive detection when parsing sync frames
A two byte sync word is not enough to ensure we got a real syncframe, nor are
all the range checks we do in the first seven bytes. Do therefore an integrity
check for the sync frame in order to prevent the parser from filling avctx with
bogus information.

Signed-off-by: James Almer <jamrial@gmail.com>
2022-10-26 10:18:33 -03:00

60 lines
1.9 KiB
C

/*
* Common AAC and AC-3 parser prototypes
* Copyright (c) 2003 Fabrice Bellard
* Copyright (c) 2003 Michael Niedermayer
*
* 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
*/
#ifndef AVCODEC_AAC_AC3_PARSER_H
#define AVCODEC_AAC_AC3_PARSER_H
#include <stdint.h>
#include "libavutil/crc.h"
#include "avcodec.h"
#include "parser.h"
typedef enum {
AAC_AC3_PARSE_ERROR_SYNC = -0x1030c0a,
AAC_AC3_PARSE_ERROR_BSID = -0x2030c0a,
AAC_AC3_PARSE_ERROR_SAMPLE_RATE = -0x3030c0a,
AAC_AC3_PARSE_ERROR_FRAME_SIZE = -0x4030c0a,
AAC_AC3_PARSE_ERROR_FRAME_TYPE = -0x5030c0a,
AAC_AC3_PARSE_ERROR_CRC = -0x6030c0a,
AAC_AC3_PARSE_ERROR_CHANNEL_CFG = -0x7030c0a,
} AACAC3ParseError;
typedef struct AACAC3ParseContext {
ParseContext pc;
int header_size;
int (*sync)(uint64_t state, int *need_next_header, int *new_frame_start);
const AVCRC *crc_ctx;
int remaining_size;
uint64_t state;
int need_next_header;
int frame_number;
} AACAC3ParseContext;
int ff_aac_ac3_parse(AVCodecParserContext *s1,
AVCodecContext *avctx,
const uint8_t **poutbuf, int *poutbuf_size,
const uint8_t *buf, int buf_size);
#endif /* AVCODEC_AAC_AC3_PARSER_H */