+/* cast5.c */
+/*
+ This file is part of the Crypto-avr-lib/microcrypt-lib.
+ Copyright (C) 2008 Daniel Otte (daniel.otte@rub.de)
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ 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.c
* \author Daniel Otte
- * \date 26.07.2006
+ * \email daniel.otte@rub.de
+ * \date 2006-07-26
* \par License:
- * GPL
+ * GPLv3 or later
* \brief Implementation of the CAST5 (aka CAST-128) cipher algorithm as described in RFC 2144
*
*/
-/**
- * \brief sets up round keys (context) for cast5 en/decryption.
- * @param s Pointer to cast5 context.
- * @param key Pointer to binary key.
- * @param keylength length of keydata in bits.
- */
-void cast5_init(cast5_ctx_t* s, uint8_t* key, uint8_t keylength){
+
+void cast5_init(void* key, uint8_t keylength_b, cast5_ctx_t* s){
/* we migth return if the key is valid and if setup was sucessfull */
uint32_t x[4], z[4];
#define BPX ((uint8_t*)&(x[0]))
#define BPZ ((uint8_t*)&(z[0]))
- s->shortkey = (keylength<=80);
+ s->shortkey = (keylength_b<=80);
/* littel endian only! */
memset(&(x[0]), 0 ,16); /* set x to zero */
- if(keylength > 128)
- keylength=128;
- memcpy(&(x[0]), key, (keylength+7)/8);
+ if(keylength_b > 128)
+ keylength_b=128;
+ memcpy(&(x[0]), key, (keylength_b+7)/8);
/* todo: merge a and b and compress the whole stuff */
return (((ia - ib) + ic) ^ id);
#else
- return (((pgm_read_dword(&s1[((uint8_t*)&t)[IA]] ) - pgm_read_dword(&s2[((uint8_t*)&t)[IB]] ))
- + pgm_read_dword(&s3[((uint8_t*)&t)[IC]] )) ^ pgm_read_dword(&s4[((uint8_t*)&t)[ID]]));
+ return (((pgm_read_dword(&s1[((uint8_t*)&t)[IA]])
+ - pgm_read_dword(&s2[((uint8_t*)&t)[IB]]) )
+ + pgm_read_dword(&s3[((uint8_t*)&t)[IC]]) )
+ ^ pgm_read_dword(&s4[((uint8_t*)&t)[ID]]) );
#endif
}
/*************************************************************************/
-/**
- * \brief encrypts a datablock with cast5
- * @param s Pointer to cast5 roundkeys (context)
- * @param block Pointer to datablock
- */
-void cast5_enc(cast5_ctx_t *s, void* block){
+void cast5_enc(void* block, const cast5_ctx_t *s){
uint32_t l,r, x, y;
uint8_t i;
cast5_f_t* f[]={cast5_f1,cast5_f2,cast5_f3};
/*************************************************************************/
-/**
- * \brief decrypts a datablock with cast5
- * @param s Pointer to cast5 roundkeys (context)
- * @param block Pointer to datablock
- */
-void cast5_dec(cast5_ctx_t *s, void* block){
+void cast5_dec(void* block, const cast5_ctx_t *s){
uint32_t l,r, x, y;
int8_t i, rounds;
cast5_f_t* f[]={cast5_f1,cast5_f2,cast5_f3};