support writing encrypted mp4 using aes-ctr, conforming to ISO/IEC 23001-7. 3 new parameters were added: - encryption_scheme - allowed values are none (default) and cenc-aes-ctr - encryption_key - 128 bit encryption key (hex) - encryption_kid - 128 bit encryption key identifier (hex) Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
		
			
				
	
	
		
			87 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			87 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * MOV CENC (Common Encryption) writer
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|  * Copyright (c) 2015 Eran Kornblau <erankor at gmail dot com>
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|  *
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|  * This file is part of FFmpeg.
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|  *
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|  * FFmpeg is free software; you can redistribute it and/or
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|  * modify it under the terms of the GNU Lesser General Public
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|  * License as published by the Free Software Foundation; either
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|  * version 2.1 of the License, or (at your option) any later version.
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|  *
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|  * FFmpeg is distributed in the hope that it will be useful,
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|  * but WITHOUT ANY WARRANTY; without even the implied warranty of
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|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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|  * Lesser General Public License for more details.
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|  *
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|  * You should have received a copy of the GNU Lesser General Public
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|  * License along with FFmpeg; if not, write to the Free Software
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|  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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|  */
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| 
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| #ifndef AVFORMAT_MOVENCCENC_H
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| #define AVFORMAT_MOVENCCENC_H
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| 
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| #include "libavutil/aes_ctr.h"
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| #include "avformat.h"
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| #include "avio.h"
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| 
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| #define CENC_KID_SIZE (16)
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| 
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| struct MOVTrack;
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| 
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| typedef struct {
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|     struct AVAESCTR* aes_ctr;
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|     uint8_t* auxiliary_info;
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|     size_t auxiliary_info_size;
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|     size_t auxiliary_info_alloc_size;
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|     uint32_t auxiliary_info_entries;
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| 
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|     /* subsample support */
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|     int use_subsamples;
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|     uint16_t subsample_count;
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|     size_t auxiliary_info_subsample_start;
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|     uint8_t* auxiliary_info_sizes;
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|     size_t  auxiliary_info_sizes_alloc_size;
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| } MOVMuxCencContext;
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| 
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| /**
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|  * Initialize a CENC context
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|  * @param key encryption key, must have a length of AES_CTR_KEY_SIZE
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|  * @param use_subsamples when enabled parts of a packet can be encrypted, otherwise the whole packet is encrypted
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|  */
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| int ff_mov_cenc_init(MOVMuxCencContext* ctx, uint8_t* encryption_key, int use_subsamples, int bitexact);
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| 
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| /**
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|  * Free a CENC context
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|  */
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| void ff_mov_cenc_free(MOVMuxCencContext* ctx);
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| 
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| /**
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|  * Write a fully encrypted packet
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|  */
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| int ff_mov_cenc_write_packet(MOVMuxCencContext* ctx, AVIOContext *pb, const uint8_t *buf_in, int size);
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| 
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| /**
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|  * Parse AVC NAL units from annex B format, the nal size and type are written in the clear while the body is encrypted
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|  */
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| int ff_mov_cenc_avc_parse_nal_units(MOVMuxCencContext* ctx, AVIOContext *pb, const uint8_t *buf_in, int size);
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| 
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| /**
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|  * Write AVC NAL units that are in MP4 format, the nal size and type are written in the clear while the body is encrypted
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|  */
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| int ff_mov_cenc_avc_write_nal_units(AVFormatContext *s, MOVMuxCencContext* ctx, int nal_length_size,
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|     AVIOContext *pb, const uint8_t *buf_in, int size);
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| 
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| /**
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|  * Write the cenc atoms that should reside inside stbl
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|  */
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| void ff_mov_cenc_write_stbl_atoms(MOVMuxCencContext* ctx, AVIOContext *pb);
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| 
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| /**
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|  * Write the sinf atom, contained inside stsd
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|  */
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| int ff_mov_cenc_write_sinf_tag(struct MOVTrack* track, AVIOContext *pb, uint8_t* kid);
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| 
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| #endif /* AVFORMAT_MOVENCCENC_H */
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