[u/mdw/catacomb] / symm / des3.c

/* -*-c-*-
 *
 * Implementation of double- and triple-DES
 *
 * (c) 1999 Straylight/Edgeware
 */

/*----- Licensing notice --------------------------------------------------*
 *
 * This file is part of Catacomb.
 *
 * Catacomb is free software; you can redistribute it and/or modify
 * 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.
 */

/*----- Header files ------------------------------------------------------*/

#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <mLib/bits.h>

#include "blkc.h"
#include "des-base.h"
#include "des.h"
#include "des3.h"
#include "gcipher.h"

/*----- Global variables --------------------------------------------------*/

const octet des3_keysz[] = { KSZ_SET, 21, 7, 8, 14, 16, 24, 0 };

/*----- Main code ---------------------------------------------------------*/

/* --- @des3_init@ --- *
 *
 * Arguments:	@des3_ctx *k@ = pointer to key block
 *		@const void *buf@ = pointer to key buffer
 *		@size_t sz@ = size of key material
 *
 * Returns:	---
 *
 * Use:		Initializes a DES key buffer.  The key buffer may have length
 *		7, 8, 14, 16, 21, or 24.  These correspond to one, two or
 *		three DES keys, either packed or unpacked (i.e., still
 *		containing parity bits).
 */

void des3_init(des3_ctx *k, const void *buf, size_t sz)
{
  size_t step;
  const octet *p = buf;

  KSZ_ASSERT(des3, sz);

  if (sz % 7 == 0)
    step = 7;
  else
    step = 8;

  des_init(&k->a, p, step);
  if (sz > 8) p += step;
  des_init(&k->b, p, step);
  if (sz > 16) p += step; else p = buf;
  des_init(&k->c, p, step);
}

/* --- @des3_eblk@, @des3_dblk@ --- *
 *
 * Arguments:	@const des3_ctx *k@ = pointer to key block
 *		@const uint32 s[2]@ = pointer to source block
 *		@uint32 d[2]@ = pointer to destination block
 *
 * Returns:	---
 *
 * Use:		Low-level block encryption and decryption.
 */

void des3_eblk(const des3_ctx *k, const uint32 *s, uint32 *d)
{
  uint32 x = s[0], y = s[1];
  DES_IP(x, y);
  DES_EBLK(k->a.k, x, y, x, y);
  DES_DBLK(k->b.k, x, y, x, y);
  DES_EBLK(k->c.k, x, y, x, y);
  DES_IPINV(x, y);
  d[0] = x, d[1] = y;
}

void des3_dblk(const des3_ctx *k, const uint32 *s, uint32 *d)
{
  uint32 x = s[0], y = s[1];
  DES_IP(x, y);
  DES_DBLK(k->c.k, x, y, x, y);
  DES_EBLK(k->b.k, x, y, x, y);
  DES_DBLK(k->a.k, x, y, x, y);
  DES_IPINV(x, y);
  d[0] = x, d[1] = y;
}

BLKC_TEST(DES3, des3)

/*----- That's all, folks -------------------------------------------------*/
Commit	Line	Data
d03ab969	1	/* --c--
d03ab969	2	*
d03ab969	3	* Implementation of double- and triple-DES
	4	*
	5	* (c) 1999 Straylight/Edgeware
	6	*/
	7
45c0fd36	8	/----- Licensing notice --------------------------------------------------
d03ab969	9	*
	10	* This file is part of Catacomb.
	11	*
	12	* Catacomb is free software; you can redistribute it and/or modify
	13	* it under the terms of the GNU Library General Public License as
	14	* published by the Free Software Foundation; either version 2 of the
	15	* License, or (at your option) any later version.
45c0fd36	16	*
d03ab969	17	* Catacomb is distributed in the hope that it will be useful,
	18	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	19	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	20	* GNU Library General Public License for more details.
45c0fd36	21	*
d03ab969	22	* You should have received a copy of the GNU Library General Public
	23	* License along with Catacomb; if not, write to the Free
	24	* Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
	25	* MA 02111-1307, USA.
	26	*/
	27
d03ab969	28	/----- Header files ------------------------------------------------------/
	29
	30	#include <assert.h>
	31	#include <stdio.h>
	32	#include <stdlib.h>
	33	#include <string.h>
	34
	35	#include <mLib/bits.h>
	36
	37	#include "blkc.h"
	38	#include "des-base.h"
	39	#include "des.h"
	40	#include "des3.h"
89ae755d	41	#include "gcipher.h"
	42
	43	/----- Global variables --------------------------------------------------/
	44
	45	const octet des3_keysz[] = { KSZ_SET, 21, 7, 8, 14, 16, 24, 0 };
d03ab969	46
	47	/----- Main code ---------------------------------------------------------/
	48
	49	/* --- @des3_init@ --- *
	50	*
	51	* Arguments: @des3_ctx *k@ = pointer to key block
	52	* @const void *buf@ = pointer to key buffer
	53	* @size_t sz@ = size of key material
	54	*
	55	* Returns: ---
	56	*
	57	* Use: Initializes a DES key buffer. The key buffer may have length
45c0fd36 MW	58	* 7, 8, 14, 16, 21, or 24. These correspond to one, two or
	59	* three DES keys, either packed or unpacked (i.e., still
	60	* containing parity bits).
d03ab969	61	*/
	62
	63	void des3_init(des3_ctx k, const void buf, size_t sz)
	64	{
	65	size_t step;
	66	const octet *p = buf;
	67
89ae755d	68	KSZ_ASSERT(des3, sz);
d03ab969	69
	70	if (sz % 7 == 0)
	71	step = 7;
	72	else
	73	step = 8;
	74
	75	des_init(&k->a, p, step);
	76	if (sz > 8) p += step;
	77	des_init(&k->b, p, step);
	78	if (sz > 16) p += step; else p = buf;
	79	des_init(&k->c, p, step);
	80	}
	81
	82	/* --- @des3_eblk@, @des3_dblk@ --- *
	83	*
	84	* Arguments: @const des3_ctx *k@ = pointer to key block
	85	* @const uint32 s[2]@ = pointer to source block
	86	* @uint32 d[2]@ = pointer to destination block
	87	*
	88	* Returns: ---
	89	*
	90	* Use: Low-level block encryption and decryption.
	91	*/
	92
	93	void des3_eblk(const des3_ctx k, const uint32 s, uint32 *d)
	94	{
	95	uint32 x = s[0], y = s[1];
	96	DES_IP(x, y);
	97	DES_EBLK(k->a.k, x, y, x, y);
	98	DES_DBLK(k->b.k, x, y, x, y);
	99	DES_EBLK(k->c.k, x, y, x, y);
	100	DES_IPINV(x, y);
	101	d[0] = x, d[1] = y;
	102	}
	103
	104	void des3_dblk(const des3_ctx k, const uint32 s, uint32 *d)
	105	{
	106	uint32 x = s[0], y = s[1];
	107	DES_IP(x, y);
	108	DES_DBLK(k->c.k, x, y, x, y);
	109	DES_EBLK(k->b.k, x, y, x, y);
	110	DES_DBLK(k->a.k, x, y, x, y);
	111	DES_IPINV(x, y);
	112	d[0] = x, d[1] = y;
	113	}
	114
	115	BLKC_TEST(DES3, des3)
	116
	117	/----- That's all, folks -------------------------------------------------/