xref: /openssl/include/crypto/poly1305.h (revision a28d06f3)
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 
20 typedef struct poly1305_context POLY1305;
21 
22 typedef void (*poly1305_blocks_f) (void *ctx, const unsigned char *inp,
23                                    size_t len, unsigned int padbit);
24 typedef void (*poly1305_emit_f) (void *ctx, unsigned char mac[16],
25                                  const unsigned int nonce[4]);
26 
27 struct 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 
41 size_t Poly1305_ctx_size(void);
42 void Poly1305_Init(POLY1305 *ctx, const unsigned char key[32]);
43 void Poly1305_Update(POLY1305 *ctx, const unsigned char *inp, size_t len);
44 void Poly1305_Final(POLY1305 *ctx, unsigned char mac[16]);
45 
46 #endif /* OSSL_CRYPTO_POLY1305_H */
47