include/crypto/poly1305.h

   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 */