3 This file is part of the AVR-Crypto-Lib.
4 Copyright (C) 2008 Daniel Otte (daniel.otte@rub.de)
6 This program is free software: you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation, either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>.
23 * \license GPLv3 or later
24 * \brief Implementation of the CAST5 (aka CAST-128) cipher algorithm as described in RFC 2144
46 /** \typedef cast5_ctx_t
47 * \brief CAST-5 context
49 * A variable of this type may hold a keyschedule for the CAST-5 cipher.
50 * This context is regulary generated by the
51 * cast5_init(uint8_t *key, uint8_t keylength_b, cast5_ctx_t *s) function.
53 typedef struct cast5_ctx_st {
55 uint8_t rotl[8]; /* 4 bit from every rotation key is stored here */
56 uint8_t roth[2]; /* 1 bit from every rotation key is stored here */
60 /** \fn void cast5_init(const void *key, uint16_t keylength_b, cast5_ctx_t *s);
61 * \brief generate keyschedule/contex for CAST-5
63 * This function generates the keyschedule from the supplied key for the
64 * CAST-5 cipher and stores it in a supplied ::cast5_ctx_t context.
65 * \param key pointer to the key
66 * \param keylength_b length of the key in bits (maximum 128 bits)
67 * \param s pointer to the context
69 void cast5_init(const void *key, uint16_t keylength_b, cast5_ctx_t *s);
71 /** \fn void cast5_enc(void *block, const cast5_ctx_t *s);
72 * \brief encrypt a block with the CAST-5 algorithm
74 * This function encrypts a block of 64 bits (8 bytes) with the CAST-5 algorithm.
75 * It uses a keyschedule as generated by the
76 * cast5_init(void *key, uint8_t keylength_b, cast5_ctx_t *s) function.
77 * \param block pointer to the block which gets encrypted
78 * \param s pointer to the keyschedule/context
80 void cast5_enc(void *block, const cast5_ctx_t *s);
82 /** \fn void cast5_dec(void *block, const cast5_ctx_t *s);
83 * \brief decrypt a block with the CAST-5 algorithm
85 * This function decrypts a block of 64 bits (8 bytes) with the CAST-5 algorithm.
86 * It uses a keyschedule as generated by the
87 * cast5_init(void *key, uint8_t keylength_b, cast5_ctx_t *s) function.
88 * \param block pointer to the block which gets decrypted
89 * \param s pointer to the keyschedule/context
91 void cast5_dec(void *block, const cast5_ctx_t *s);