modified structure

[avr-crypto-lib.git] / rc6.c

diff --git a/rc6.c b/rc6.c
deleted file mode 100644 (file)
index ea4d7bb..0000000
--- a/rc6.c
+++ /dev/null
@@ -1,148 +0,0 @@
-/* rc6.c */
-/*
-    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
-    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:       rc6.c
- * Author:     Daniel Otte
- * Date:       06.08.2006
- * License: GPL
- * Description: Implementation of the RC6 cipher algorithm.
- *     This implementation is restricted to 32-bit words and to keys up to 65535 bit in length (but this is
- *  quite easy to expand), but free in the choice of number of rounds (0 to 125).
- *     so it is RC6-32/r/b
- * THIS ONLY WORKS FOR LITTEL ENDIAN!!!
- */
- 
-#include <stdint.h>
-#include <stdlib.h>
-#include "rc6.h"
-#include "config.h"
- 
-#define P32 0xB7E15163         /* e -2 */
-#define Q32 0x9E3779B9         /* Golden Ratio -1 */
- 
-uint32_t rotl32(uint32_t a, uint8_t n){
-       n &= 0x1f; /* higher rotates would not bring anything */
-       return ( (a<<n)| (a>>(32-n)) );
-}
-
-uint32_t rotr32(uint32_t a, uint8_t n){
-       n &= 0x1f; /* higher rotates would not bring anything */
-       return ( (a>>n)| (a<<(32-n)) );
-}
- 
-uint8_t rc6_init(void* key, uint16_t keylength_b, rc6_ctx_t *s){
-       return rc6_initl(key, keylength_b, 20, s);
-}
- 
- 
-uint8_t rc6_initl(void* key, uint16_t keylength_b, uint8_t rounds, rc6_ctx_t *s){
-       uint8_t i,j;
-       uint16_t v,p,c;
-       uint32_t a,b, l=0;
-       if (rounds>125)
-               return 2;
-       if(!(s->S=malloc((2*rounds+4)*sizeof(uint32_t))))
-               return 1;
-       
-       s->rounds=rounds;
-       
-       c = keylength_b/32;
-       if (keylength_b%32){ 
-               ++c;
-               j=(keylength_b%32)/8;
-               if(keylength_b%8)
-                       ++j;
-               for (i=0; i<j; ++i) 
-                       ((uint8_t*)&l)[i] = ((uint8_t*)key)[(c-1)*4 + i];
-       } else {
-               l = ((uint32_t*)key)[c-1];
-       }
-       
-       s->S[0] = P32;
-       for(i=1; i<2*rounds+4; ++i){
-               s->S[i] = s->S[i-1] + Q32;
-       }
-       
-       a=b=j=i=0;
-       v = 3 * ((c > 2*rounds+4)?c:(2*rounds+4));
-       for(p=1; p<=v; ++p){
-               a = s->S[i] = rotl32(s->S[i] + a + b, 3);
-               if (j==c-1){
-                       b = l = rotl32(l+a+b, a+b);
-               } else {
-                       b = ((uint32_t*)key)[j] = rotl32(((uint32_t*)key)[j]+a+b, a+b);
-               }
-               i = (i+1) % (2*rounds+4);
-               j = (j+1) % c;
-       }
-       return 0;
-}
- 
-void rc6_free(rc6_ctx_t *s){
-       free(s->S);
-} 
- 
-#define LG_W 5
-#define A (((uint32_t*)block)[0])
-#define B (((uint32_t*)block)[1])
-#define C (((uint32_t*)block)[2])
-#define D (((uint32_t*)block)[3])
- 
-void rc6_enc(void* block, rc6_ctx_t *s){
-       uint8_t i;
-       uint32_t t,u,x; /* greetings to Linux? */
-       B += s->S[0];
-       D += s->S[1];
-       for (i=1; i<=s->rounds; ++i){
-               t = rotl32(B * (2*B+1), LG_W);
-               u = rotl32(D * (2*D+1), LG_W);
-               A = rotl32((A ^ t), u) + s->S[2*i];
-               C = rotl32((C ^ u), t) + s->S[2*i+1];
-               x = A;
-               A = B;
-               B = C;
-               C = D;
-               D = x;
-       }
-       A += s->S[2*s->rounds+2];
-       C += s->S[2*s->rounds+3];
-}
- 
-void rc6_dec(void* block, rc6_ctx_t *s){
-       uint8_t i;
-       uint32_t t,u,x; /* greetings to Linux? */
- 
-       C -= s->S[2*s->rounds+3];
-       A -= s->S[2*s->rounds+2];
-       
-       for (i=s->rounds; i>0; --i){
-               x=D;
-               D=C;
-               C=B;
-               B=A;
-               A=x;
-               u = rotl32(D * (2*D+1), LG_W);
-               t = rotl32(B * (2*B+1), LG_W);
-               C = rotr32(C - s->S[2*i+1], t) ^ u;
-               A = rotr32(A - s->S[2*i+0], u) ^ t;
-       }
-       D -= s->S[1];
-       B -= s->S[0];
-}
-