1/* twofish.h
2
3 The twofish block cipher.
4
5 Copyright (C) 2001, 2014 Niels Möller
6
7 This file is part of GNU Nettle.
8
9 GNU Nettle is free software: you can redistribute it and/or
10 modify it under the terms of either:
11
12 * the GNU Lesser General Public License as published by the Free
13 Software Foundation; either version 3 of the License, or (at your
14 option) any later version.
15
16 or
17
18 * the GNU General Public License as published by the Free
19 Software Foundation; either version 2 of the License, or (at your
20 option) any later version.
21
22 or both in parallel, as here.
23
24 GNU Nettle is distributed in the hope that it will be useful,
25 but WITHOUT ANY WARRANTY; without even the implied warranty of
26 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
27 General Public License for more details.
28
29 You should have received copies of the GNU General Public License and
30 the GNU Lesser General Public License along with this program. If
31 not, see http://www.gnu.org/licenses/.
32*/
33
34/*
35 * Twofish is a 128-bit block cipher that accepts a variable-length
36 * key up to 256 bits, designed by Bruce Schneier and others. See
37 * http://www.counterpane.com/twofish.html for details.
38 */
39
40#ifndef NETTLE_TWOFISH_H_INCLUDED
41#define NETTLE_TWOFISH_H_INCLUDED
42
43#include "nettle-types.h"
44
45#ifdef __cplusplus
46extern "C" {
47#endif
48
49/* Name mangling */
50#define twofish_set_key nettle_twofish_set_key
51#define twofish128_set_key nettle_twofish128_set_key
52#define twofish192_set_key nettle_twofish192_set_key
53#define twofish256_set_key nettle_twofish256_set_key
54#define twofish_encrypt nettle_twofish_encrypt
55#define twofish_decrypt nettle_twofish_decrypt
56
57#define TWOFISH_BLOCK_SIZE 16
58
59/* Variable key size between 128 and 256 bits. But the only valid
60 * values are 16 (128 bits), 24 (192 bits) and 32 (256 bits). */
61#define TWOFISH_MIN_KEY_SIZE 16
62#define TWOFISH_MAX_KEY_SIZE 32
63
64#define TWOFISH_KEY_SIZE 32
65#define TWOFISH128_KEY_SIZE 16
66#define TWOFISH192_KEY_SIZE 24
67#define TWOFISH256_KEY_SIZE 32
68
69struct twofish_ctx
70{
71 uint32_t keys[40];
72 uint32_t s_box[4][256];
73};
74
75void
76twofish_set_key(struct twofish_ctx *ctx,
77 size_t length, const uint8_t *key);
78void
79twofish128_set_key(struct twofish_ctx *context, const uint8_t *key);
80void
81twofish192_set_key(struct twofish_ctx *context, const uint8_t *key);
82void
83twofish256_set_key(struct twofish_ctx *context, const uint8_t *key);
84
85void
86twofish_encrypt(const struct twofish_ctx *ctx,
87 size_t length, uint8_t *dst,
88 const uint8_t *src);
89void
90twofish_decrypt(const struct twofish_ctx *ctx,
91 size_t length, uint8_t *dst,
92 const uint8_t *src);
93
94#ifdef __cplusplus
95}
96#endif
97
98#endif /* NETTLE_TWOFISH_H_INCLUDED */
99