blob: f596fa6a46bac698aca25ebb1967e96fe22c549b
| 1 | /* |
| 2 | * AES-CTR cipher |
| 3 | * Copyright (c) 2015 Eran Kornblau <erankor at gmail dot com> |
| 4 | * |
| 5 | * This file is part of FFmpeg. |
| 6 | * |
| 7 | * FFmpeg is free software; you can redistribute it and/or |
| 8 | * modify it under the terms of the GNU Lesser General Public |
| 9 | * License as published by the Free Software Foundation; either |
| 10 | * version 2.1 of the License, or (at your option) any later version. |
| 11 | * |
| 12 | * FFmpeg is distributed in the hope that it will be useful, |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 15 | * Lesser General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU Lesser General Public |
| 18 | * License along with FFmpeg; if not, write to the Free Software |
| 19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 20 | */ |
| 21 | |
| 22 | #ifndef AVUTIL_AES_CTR_H |
| 23 | #define AVUTIL_AES_CTR_H |
| 24 | |
| 25 | #include <stdint.h> |
| 26 | |
| 27 | #include "attributes.h" |
| 28 | #include "version.h" |
| 29 | |
| 30 | #define AES_CTR_KEY_SIZE (16) |
| 31 | #define AES_CTR_IV_SIZE (8) |
| 32 | |
| 33 | struct AVAESCTR; |
| 34 | |
| 35 | /** |
| 36 | * Allocate an AVAESCTR context. |
| 37 | */ |
| 38 | struct AVAESCTR *av_aes_ctr_alloc(void); |
| 39 | |
| 40 | /** |
| 41 | * Initialize an AVAESCTR context. |
| 42 | * @param key encryption key, must have a length of AES_CTR_KEY_SIZE |
| 43 | */ |
| 44 | int av_aes_ctr_init(struct AVAESCTR *a, const uint8_t *key); |
| 45 | |
| 46 | /** |
| 47 | * Release an AVAESCTR context. |
| 48 | */ |
| 49 | void av_aes_ctr_free(struct AVAESCTR *a); |
| 50 | |
| 51 | /** |
| 52 | * Process a buffer using a previously initialized context. |
| 53 | * @param dst destination array, can be equal to src |
| 54 | * @param src source array, can be equal to dst |
| 55 | * @param size the size of src and dst |
| 56 | */ |
| 57 | void av_aes_ctr_crypt(struct AVAESCTR *a, uint8_t *dst, const uint8_t *src, int size); |
| 58 | |
| 59 | /** |
| 60 | * Get the current iv |
| 61 | */ |
| 62 | const uint8_t* av_aes_ctr_get_iv(struct AVAESCTR *a); |
| 63 | |
| 64 | /** |
| 65 | * Generate a random iv |
| 66 | */ |
| 67 | void av_aes_ctr_set_random_iv(struct AVAESCTR *a); |
| 68 | |
| 69 | /** |
| 70 | * Forcefully change the iv |
| 71 | */ |
| 72 | void av_aes_ctr_set_iv(struct AVAESCTR *a, const uint8_t* iv); |
| 73 | |
| 74 | /** |
| 75 | * Increment the top 64 bit of the iv (performed after each frame) |
| 76 | */ |
| 77 | void av_aes_ctr_increment_iv(struct AVAESCTR *a); |
| 78 | |
| 79 | /** |
| 80 | * @} |
| 81 | */ |
| 82 | |
| 83 | #endif /* AVUTIL_AES_CTR_H */ |
| 84 |