/* cast5.h */
/*
- This file is part of the Crypto-avr-lib/microcrypt-lib.
+ This file is part of the AVR-Crypto-Lib.
Copyright (C) 2008 Daniel Otte (daniel.otte@rub.de)
This program is free software: you can redistribute it and/or modify
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
-/*
- * File: cast5.h
- * Author: Daniel Otte
- * Date: 26.07.2006
- * License: GPL
- * Description: Implementation of the CAST5 (aka CAST-128) cipher algorithm as described in RFC 2144
+/**
+ * \file cast5.h
+ * \author Daniel Otte
+ * \date 2006-07-26
+ * \license GPLv3 or later
+ * \brief Implementation of the CAST5 (aka CAST-128) cipher algorithm as described in RFC 2144
*
*/
+
#ifndef CAST5_H_
#define CAST5_H_
#endif
#endif
-
+/** \typedef cast5_ctx_t
+ * \brief CAST-5 context
+ *
+ * A variable of this type may hold a keyschedule for the CAST-5 cipher.
+ * This context is regulary generated by the
+ * cast5_init(uint8_t* key, uint8_t keylength_b, cast5_ctx_t* s) function.
+ */
typedef struct cast5_ctx_st{
uint32_t mask[16];
uint8_t rotl[8]; /* 4 bit from every rotation key is stored here */
bool shortkey;
} cast5_ctx_t;
-void cast5_init(cast5_ctx_t* s, uint8_t* key, uint8_t keylength);
-void cast5_enc(cast5_ctx_t *s, void* block);
-void cast5_dec(cast5_ctx_t *s, void* block);
+
+/** \fn void cast5_init(const void* key, uint16_t keylength_b, cast5_ctx_t* s);
+ * \brief generate keyschedule/contex for CAST-5
+ *
+ * This function generates the keyschedule from the supplied key for the
+ * CAST-5 cipher and stores it in a supplied ::cast5_ctx_t context.
+ * \param key pointer to the key
+ * \param keylength_b length of the key in bits (maximum 128 bits)
+ * \param s pointer to the context
+ */
+void cast5_init(const void* key, uint16_t keylength_b, cast5_ctx_t* s);
+
+/** \fn void cast5_enc(void* block, const cast5_ctx_t* s);
+ * \brief encrypt a block with the CAST-5 algorithm
+ *
+ * This function encrypts a block of 64 bits (8 bytes) with the CAST-5 algorithm.
+ * It uses a keyschedule as generated by the
+ * cast5_init(void* key, uint8_t keylength_b, cast5_ctx_t* s) function.
+ * \param block pointer to the block which gets encrypted
+ * \param s pointer to the keyschedule/context
+ */
+void cast5_enc(void* block, const cast5_ctx_t* s);
+
+/** \fn void cast5_dec(void* block, const cast5_ctx_t* s);
+ * \brief decrypt a block with the CAST-5 algorithm
+ *
+ * This function decrypts a block of 64 bits (8 bytes) with the CAST-5 algorithm.
+ * It uses a keyschedule as generated by the
+ * cast5_init(void* key, uint8_t keylength_b, cast5_ctx_t* s) function.
+ * \param block pointer to the block which gets decrypted
+ * \param s pointer to the keyschedule/context
+ */
+void cast5_dec(void* block, const cast5_ctx_t* s);