/** * 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 AVUTIL_ENCRYPTION_INFO_H #define AVUTIL_ENCRYPTION_INFO_H #include <stddef.h> #include <stdint.h> typedef struct AVSubsampleEncryptionInfo { /** The number of bytes that are clear. */ unsigned int bytes_of_clear_data; /** * The number of bytes that are protected. If using pattern encryption, * the pattern applies to only the protected bytes; if not using pattern * encryption, all these bytes are encrypted. */ unsigned int bytes_of_protected_data; } AVSubsampleEncryptionInfo; /** * This describes encryption info for a packet. This contains frame-specific * info for how to decrypt the packet before passing it to the decoder. * * The size of this struct is not part of the public ABI. */ typedef struct AVEncryptionInfo { /** The fourcc encryption scheme, in big-endian byte order. */ uint32_t scheme; /** * Only used for pattern encryption. This is the number of 16-byte blocks * that are encrypted. */ uint32_t crypt_byte_block; /** * Only used for pattern encryption. This is the number of 16-byte blocks * that are clear. */ uint32_t skip_byte_block; /** * The ID of the key used to encrypt the packet. This should always be * 16 bytes long, but may be changed in the future. */ uint8_t *key_id; uint32_t key_id_size; /** * The initialization vector. This may have been zero-filled to be the * correct block size. This should always be 16 bytes long, but may be * changed in the future. */ uint8_t *iv; uint32_t iv_size; /** * An array of subsample encryption info specifying how parts of the sample * are encrypted. If there are no subsamples, then the whole sample is * encrypted. */ AVSubsampleEncryptionInfo *subsamples; uint32_t subsample_count; } AVEncryptionInfo; /** * This describes info used to initialize an encryption key system. * * The size of this struct is not part of the public ABI. */ typedef struct AVEncryptionInitInfo { /** * A unique identifier for the key system this is for, can be NULL if it * is not known. This should always be 16 bytes, but may change in the * future. */ uint8_t* system_id; uint32_t system_id_size; /** * An array of key IDs this initialization data is for. All IDs are the * same length. Can be NULL if there are no known key IDs. */ uint8_t** key_ids; /** The number of key IDs. */ uint32_t num_key_ids; /** * The number of bytes in each key ID. This should always be 16, but may * change in the future. */ uint32_t key_id_size; /** * Key-system specific initialization data. This data is copied directly * from the file and the format depends on the specific key system. This * can be NULL if there is no initialization data; in that case, there * will be at least one key ID. */ uint8_t* data; uint32_t data_size; /** * An optional pointer to the next initialization info in the list. */ struct AVEncryptionInitInfo *next; } AVEncryptionInitInfo; /** * Allocates an AVEncryptionInfo structure and sub-pointers to hold the given * number of subsamples. This will allocate pointers for the key ID, IV, * and subsample entries, set the size members, and zero-initialize the rest. * * @param subsample_count The number of subsamples. * @param key_id_size The number of bytes in the key ID, should be 16. * @param iv_size The number of bytes in the IV, should be 16. * * @return The new AVEncryptionInfo structure, or NULL on error. */ AVEncryptionInfo *av_encryption_info_alloc(uint32_t subsample_count, uint32_t key_id_size, uint32_t iv_size); /** * Allocates an AVEncryptionInfo structure with a copy of the given data. * @return The new AVEncryptionInfo structure, or NULL on error. */ AVEncryptionInfo *av_encryption_info_clone(const AVEncryptionInfo *info); /** * Frees the given encryption info object. This MUST NOT be used to free the * side-data data pointer, that should use normal side-data methods. */ void av_encryption_info_free(AVEncryptionInfo *info); /** * Creates a copy of the AVEncryptionInfo that is contained in the given side * data. The resulting object should be passed to av_encryption_info_free() * when done. * * @return The new AVEncryptionInfo structure, or NULL on error. */ AVEncryptionInfo *av_encryption_info_get_side_data(const uint8_t *side_data, size_t side_data_size); /** * Allocates and initializes side data that holds a copy of the given encryption * info. The resulting pointer should be either freed using av_free or given * to av_packet_add_side_data(). * * @return The new side-data pointer, or NULL. */ uint8_t *av_encryption_info_add_side_data( const AVEncryptionInfo *info, size_t *side_data_size); /** * Allocates an AVEncryptionInitInfo structure and sub-pointers to hold the * given sizes. This will allocate pointers and set all the fields. * * @return The new AVEncryptionInitInfo structure, or NULL on error. */ AVEncryptionInitInfo *av_encryption_init_info_alloc( uint32_t system_id_size, uint32_t num_key_ids, uint32_t key_id_size, uint32_t data_size); /** * Frees the given encryption init info object. This MUST NOT be used to free * the side-data data pointer, that should use normal side-data methods. */ void av_encryption_init_info_free(AVEncryptionInitInfo* info); /** * Creates a copy of the AVEncryptionInitInfo that is contained in the given * side data. The resulting object should be passed to * av_encryption_init_info_free() when done. * * @return The new AVEncryptionInitInfo structure, or NULL on error. */ AVEncryptionInitInfo *av_encryption_init_info_get_side_data( const uint8_t* side_data, size_t side_data_size); /** * Allocates and initializes side data that holds a copy of the given encryption * init info. The resulting pointer should be either freed using av_free or * given to av_packet_add_side_data(). * * @return The new side-data pointer, or NULL. */ uint8_t *av_encryption_init_info_add_side_data( const AVEncryptionInitInfo *info, size_t *side_data_size); #endif /* AVUTIL_ENCRYPTION_INFO_H */