1/*
2 * Copyright 2015-2021 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the Apache License 2.0 (the "License").  You may not use
5 * this file except in compliance with the License.  You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10#ifndef OSSL_CRYPTO_POLY1305_H
11# define OSSL_CRYPTO_POLY1305_H
12# pragma once
13
14#include <stddef.h>
15
16#define POLY1305_BLOCK_SIZE  16
17#define POLY1305_DIGEST_SIZE 16
18#define POLY1305_KEY_SIZE    32
19
20typedef struct poly1305_context POLY1305;
21
22typedef void (*poly1305_blocks_f) (void *ctx, const unsigned char *inp,
23                                   size_t len, unsigned int padbit);
24typedef void (*poly1305_emit_f) (void *ctx, unsigned char mac[16],
25                                 const unsigned int nonce[4]);
26
27struct poly1305_context {
28    double opaque[24];  /* large enough to hold internal state, declared
29                         * 'double' to ensure at least 64-bit invariant
30                         * alignment across all platforms and
31                         * configurations */
32    unsigned int nonce[4];
33    unsigned char data[POLY1305_BLOCK_SIZE];
34    size_t num;
35    struct {
36        poly1305_blocks_f blocks;
37        poly1305_emit_f emit;
38    } func;
39};
40
41size_t Poly1305_ctx_size(void);
42void Poly1305_Init(POLY1305 *ctx, const unsigned char key[32]);
43void Poly1305_Update(POLY1305 *ctx, const unsigned char *inp, size_t len);
44void Poly1305_Final(POLY1305 *ctx, unsigned char mac[16]);
45
46#endif /* OSSL_CRYPTO_POLY1305_H */
47