/* -*-c-*-
*
- * $Id: tea.c,v 1.1 2000/07/15 13:44:31 mdw Exp $
+ * $Id: tea.c,v 1.3 2004/04/08 01:36:15 mdw Exp $
*
* The Tiny Encryption Algorithm
*
* (c) 2000 Straylight/Edgeware
*/
-/*----- Licensing notice --------------------------------------------------*
+/*----- Licensing notice --------------------------------------------------*
*
* This file is part of Catacomb.
*
* it under the terms of the GNU Library General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
- *
+ *
* Catacomb 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 Library General Public License for more details.
- *
+ *
* You should have received a copy of the GNU Library General Public
* License along with Catacomb; if not, write to the Free
* Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
* MA 02111-1307, USA.
*/
-/*----- Revision history --------------------------------------------------*
- *
- * $Log: tea.c,v $
- * Revision 1.1 2000/07/15 13:44:31 mdw
- * New ciphers.
- *
- */
-
/*----- Header files ------------------------------------------------------*/
#include <mLib/bits.h>
/* --- @tea_init@ --- *
*
- * Arguments: @tea_ctx *k@ = pointer to key block
- * @const void *buf@ = pointer to key buffer
- * @size_t sz@ = size of key material
+ * Arguments: @tea_ctx *k@ = pointer to key block
+ * @const void *buf@ = pointer to key buffer
+ * @size_t sz@ = size of key material
*
- * Returns: ---
+ * Returns: ---
*
- * Use: Initializes a TEA key buffer. The key buffer must be 16
+ * Use: Initializes a TEA key buffer. The key buffer must be 16
* bytes long.
*/
p = kb;
}
- k->ka = LOAD32(p + 0); k->kb = LOAD32(p + 4);
- k->kc = LOAD32(p + 8); k->kd = LOAD32(p + 12);
+ k->ka = LOAD32(p + 0); k->kb = LOAD32(p + 4);
+ k->kc = LOAD32(p + 8); k->kd = LOAD32(p + 12);
+ k->r = 32;
if (p == kb)
BURN(kb);
/* --- @tea_eblk@, @tea_dblk@ --- *
*
- * Arguments: @const tea_ctx *k@ = pointer to key block
- * @const uint32 s[2]@ = pointer to source block
- * @uint32 d[2]@ = pointer to teatination block
+ * Arguments: @const tea_ctx *k@ = pointer to key block
+ * @const uint32 s[2]@ = pointer to source block
+ * @uint32 d[2]@ = pointer to teatination block
*
- * Returns: ---
+ * Returns: ---
*
- * Use: Low-level block encryption and decryption.
+ * Use: Low-level block encryption and decryption.
*/
#define DELTA 0x9e3779b9
uint32 n = 0;
unsigned i;
- for (i = 0; i < 32; i++) {
+ for (i = 0; i < k->r; i++) {
n += DELTA;
y = U32(y + (((z << 4) + ka) ^ (z + n) ^ ((z >> 5) + kb)));
z = U32(z + (((y << 4) + kc) ^ (y + n) ^ ((y >> 5) + kd)));
{
uint32 y = s[0], z = s[1];
uint32 ka = k->ka, kb = k->kb, kc = k->kc, kd = k->kd;
- uint32 n = DELTA << 5;
+ uint32 n = DELTA * k->r;
unsigned i;
- for (i = 0; i < 32; i++) {
+ for (i = 0; i < k->r; i++) {
z = U32(z - (((y << 4) + kc) ^ (y + n) ^ ((y >> 5) + kd)));
y = U32(y - (((z << 4) + ka) ^ (z + n) ^ ((z >> 5) + kb)));
n -= DELTA;