/*
 * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
 * unrestricted use provided that this legend is included on all tape
 * media and as a part of the software program in whole or part.  Users
 * may copy or modify Sun RPC without charge, but are not authorized
 * to license or distribute it to anyone else except as part of a product or
 * program developed by the user.
 * 
 * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
 * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
 * 
 * Sun RPC is provided with no support and without any obligation on the
 * part of Sun Microsystems, Inc. to assist in its use, correction,
 * modification or enhancement.
 * 
 * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
 * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
 * OR ANY PART THEREOF.
 * 
 * In no event will Sun Microsystems, Inc. be liable for any lost revenue
 * or profits or other special, indirect and consequential damages, even if
 * Sun has been advised of the possibility of such damages.
 * 
 * Sun Microsystems, Inc.
 * 2550 Garcia Avenue
 * Mountain View, California  94043
 */
#if !defined(lint) && defined(SCCSID)
static char sccsid[] = "@(#)des_crypt.c	2.2 88/08/10 4.0 RPCSRC; from 1.13 88/02/08 SMI";
#endif
/*
 * des_crypt.c, DES encryption library routines
 * Copyright (C) 1986, Sun Microsystems, Inc.
 */

#include <sys/types.h>
#include <rpc/des_crypt.h>
#include "des.h"

extern int nis_des_crypt (char *, unsigned, struct desparams *);

/*
 * Copy 8 bytes
 */
#define COPY8(src, dst) { \
	register char *a = (char *) dst; \
	register char *b = (char *) src; \
	*a++ = *b++; *a++ = *b++; *a++ = *b++; *a++ = *b++; \
	*a++ = *b++; *a++ = *b++; *a++ = *b++; *a++ = *b++; \
}

/*
 * Copy multiple of 8 bytes
 */
#define DESCOPY(src, dst, len) { \
	register char *a = (char *) dst; \
	register char *b = (char *) src; \
	register int i; \
	for (i = (int) len; i > 0; i -= 8) { \
		*a++ = *b++; *a++ = *b++; *a++ = *b++; *a++ = *b++; \
		*a++ = *b++; *a++ = *b++; *a++ = *b++; *a++ = *b++; \
	} \
}

/*
 * Common code to cbc_crypt() & ecb_crypt()
 */
static int
common_crypt (char *key, char *buf, register unsigned len,
	      unsigned mode, register struct desparams *desp)
{
  register int desdev;

  if ((len % 8) != 0 || len > DES_MAXDATA)
    return DESERR_BADPARAM;

  desp->des_dir =
    ((mode & DES_DIRMASK) == DES_ENCRYPT) ? ENCRYPT : DECRYPT;

  desdev = mode & DES_DEVMASK;
  COPY8 (key, desp->des_key);
  /* 
   * software
   */
  if (!nis_des_crypt (buf, len, desp))
    return DESERR_HWERROR;

  return desdev == DES_SW ? DESERR_NONE : DESERR_NOHWDEVICE;
}

/*
 * CBC mode encryption
 */
int
cbc_crypt (char *key, char *buf, unsigned int len, unsigned int mode,
	   char *ivec)
{
  int err;
  struct desparams dp;

  dp.des_mode = CBC;
  COPY8 (ivec, dp.des_ivec);
  err = common_crypt (key, buf, len, mode, &dp);
  COPY8 (dp.des_ivec, ivec);
  return err;
}


/*
 * ECB mode encryption
 */
int
ecb_crypt (char *key, char *buf, unsigned int len, unsigned int mode)
{
  struct desparams dp;

  dp.des_mode = ECB;
  return common_crypt (key, buf, len, mode, &dp);
}
