| 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
| 2 | /* |
| 3 | * Common values for the Poly1305 algorithm |
| 4 | */ |
| 5 | |
| 6 | #ifndef _CRYPTO_POLY1305_H |
| 7 | #define _CRYPTO_POLY1305_H |
| 8 | |
| 9 | #include <linux/types.h> |
| 10 | |
| 11 | #define POLY1305_BLOCK_SIZE 16 |
| 12 | #define POLY1305_KEY_SIZE 32 |
| 13 | #define POLY1305_DIGEST_SIZE 16 |
| 14 | |
| 15 | /* The poly1305_key and poly1305_state types are mostly opaque and |
| 16 | * implementation-defined. Limbs might be in base 2^64 or base 2^26, or |
| 17 | * different yet. The union type provided keeps these 64-bit aligned for the |
| 18 | * case in which this is implemented using 64x64 multiplies. |
| 19 | */ |
| 20 | |
| 21 | struct poly1305_key { |
| 22 | union { |
| 23 | u32 r[5]; |
| 24 | u64 r64[3]; |
| 25 | }; |
| 26 | }; |
| 27 | |
| 28 | struct poly1305_core_key { |
| 29 | struct poly1305_key key; |
| 30 | struct poly1305_key precomputed_s; |
| 31 | }; |
| 32 | |
| 33 | struct poly1305_state { |
| 34 | union { |
| 35 | u32 h[5]; |
| 36 | u64 h64[3]; |
| 37 | }; |
| 38 | }; |
| 39 | |
| 40 | /* Combined state for block function. */ |
| 41 | struct poly1305_block_state { |
| 42 | /* accumulator */ |
| 43 | struct poly1305_state h; |
| 44 | /* key */ |
| 45 | union { |
| 46 | struct poly1305_key opaque_r[CONFIG_CRYPTO_LIB_POLY1305_RSIZE]; |
| 47 | struct poly1305_core_key core_r; |
| 48 | }; |
| 49 | }; |
| 50 | |
| 51 | struct poly1305_desc_ctx { |
| 52 | /* partial buffer */ |
| 53 | u8 buf[POLY1305_BLOCK_SIZE]; |
| 54 | /* bytes used in partial buffer */ |
| 55 | unsigned int buflen; |
| 56 | /* finalize key */ |
| 57 | u32 s[4]; |
| 58 | struct poly1305_block_state state; |
| 59 | }; |
| 60 | |
| 61 | void poly1305_init(struct poly1305_desc_ctx *desc, |
| 62 | const u8 key[at_least POLY1305_KEY_SIZE]); |
| 63 | void poly1305_update(struct poly1305_desc_ctx *desc, |
| 64 | const u8 *src, unsigned int nbytes); |
| 65 | void poly1305_final(struct poly1305_desc_ctx *desc, u8 *digest); |
| 66 | |
| 67 | #endif |
| 68 | |