1// Copyright (c) 2015-present The Bitcoin Core developers
2// Distributed under the MIT software license, see the accompanying
3// file COPYING or http://www.opensource.org/licenses/mit-license.php.
4//
5// C++ wrapper around ctaes, a constant-time AES implementation
6
7#ifndef BITCOIN_CRYPTO_AES_H
8#define BITCOIN_CRYPTO_AES_H
9
10#include <support/allocators/secure.h>
11extern "C" {
12#include <crypto/ctaes/ctaes.h>
13}
14
15inline constexpr int AES_BLOCKSIZE = 16;
16inline constexpr int AES256_KEYSIZE = 32;
17
18/** An encryption class for AES-256. */
19class AES256Encrypt
20{
21private:
22    secure_allocator<AES256_ctx> allocator;
23    AES256_ctx *ctx;
24
25public:
26    explicit AES256Encrypt(const unsigned char key[32]);
27    ~AES256Encrypt();
28    void Encrypt(unsigned char ciphertext[16], const unsigned char plaintext[16]) const;
29};
30
31/** A decryption class for AES-256. */
32class AES256Decrypt
33{
34private:
35    secure_allocator<AES256_ctx> allocator;
36    AES256_ctx *ctx;
37
38public:
39    explicit AES256Decrypt(const unsigned char key[32]);
40    ~AES256Decrypt();
41    void Decrypt(unsigned char plaintext[16], const unsigned char ciphertext[16]) const;
42};
43
44class AES256CBCEncrypt
45{
46public:
47    AES256CBCEncrypt(const unsigned char key[AES256_KEYSIZE], const unsigned char ivIn[AES_BLOCKSIZE], bool padIn);
48    ~AES256CBCEncrypt();
49    int Encrypt(const unsigned char* data, int size, unsigned char* out) const;
50
51private:
52    secure_allocator<unsigned char> allocator;
53    const AES256Encrypt enc;
54    const bool pad;
55    unsigned char *iv;
56};
57
58class AES256CBCDecrypt
59{
60public:
61    AES256CBCDecrypt(const unsigned char key[AES256_KEYSIZE], const unsigned char ivIn[AES_BLOCKSIZE], bool padIn);
62    ~AES256CBCDecrypt();
63    int Decrypt(const unsigned char* data, int size, unsigned char* out) const;
64
65private:
66    secure_allocator<unsigned char> allocator;
67    const AES256Decrypt dec;
68    const bool pad;
69    unsigned char *iv;
70};
71
72#endif // BITCOIN_CRYPTO_AES_H
73