/* -*-c-*-
*
- * $Id: idea.c,v 1.3 2000/07/02 18:24:39 mdw Exp $
+ * $Id: idea.c,v 1.5 2004/04/08 01:36:15 mdw Exp $
*
* Implementation of the IDEA cipher
*
* MA 02111-1307, USA.
*/
-/*----- Revision history --------------------------------------------------*
- *
- * $Log: idea.c,v $
- * Revision 1.3 2000/07/02 18:24:39 mdw
- * Use a new multiplication function from an Ascom white paper to resist
- * timing attacks.
- *
- * Revision 1.2 2000/06/17 11:24:08 mdw
- * New key size interface.
- *
- * Revision 1.1 1999/09/03 08:41:12 mdw
- * Initial import.
- *
- */
-
/*----- Header files ------------------------------------------------------*/
#include <assert.h>
{
uint32 m = 0x10001;
uint32 a = 1, b = 0;
+ uint32 nn = n;
+ if (!nn)
+ nn = 0x10000;
for (;;) {
uint32 q, r, t;
- if (!(r = m % n))
+ if (!(r = m % nn))
break;
- q = m / n;
- m = n; n = r;
+ q = m / nn;
+ m = nn; nn = r;
t = a; a = b - q * a; b = t;
}
if (a > MASK16)
ROUND(_k, _a, _b, _c, _d); \
ROUND(_k, _a, _c, _b, _d); \
MIX (_k, _a, _c, _b, _d); \
- c = (U16(_a) << 16) | U16(_c); \
- d = (U16(_b) << 16) | U16(_d); \
+ c = ((uint32)U16(_a) << 16) | (uint32)U16(_c); \
+ d = ((uint32)U16(_b) << 16) | (uint32)U16(_d); \
} while (0)
#define DBLK(k, a, b) EBLK((k), (a), (b))