freebsd-nq/secure/lib/libdes/cbc_enc.c

115 lines
3.7 KiB
C

/* crypto/des/cbc_enc.c */
/* Copyright (C) 1995-1996 Eric Young (eay@mincom.oz.au)
* All rights reserved.
*
* This file is part of an SSL implementation written
* by Eric Young (eay@mincom.oz.au).
* The implementation was written so as to conform with Netscapes SSL
* specification. This library and applications are
* FREE FOR COMMERCIAL AND NON-COMMERCIAL USE
* as long as the following conditions are aheared to.
*
* Copyright remains Eric Young's, and as such any Copyright notices in
* the code are not to be removed. If this code is used in a product,
* Eric Young should be given attribution as the author of the parts used.
* This can be in the form of a textual message at program startup or
* in documentation (online or textual) provided with the package.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Eric Young (eay@mincom.oz.au)
*
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* The licence and distribution terms for any publically available version or
* derivative of this code cannot be changed. i.e. this code cannot simply be
* copied and put under another distribution licence
* [including the GNU Public Licence.]
*/
#include "des_locl.h"
void des_cbc_encrypt(input, output, length, schedule, ivec, encrypt)
des_cblock (*input);
des_cblock (*output);
long length;
des_key_schedule schedule;
des_cblock (*ivec);
int encrypt;
{
register DES_LONG tin0,tin1;
register DES_LONG tout0,tout1,xor0,xor1;
register unsigned char *in,*out;
register long l=length;
DES_LONG tin[2];
unsigned char *iv;
in=(unsigned char *)input;
out=(unsigned char *)output;
iv=(unsigned char *)ivec;
if (encrypt)
{
c2l(iv,tout0);
c2l(iv,tout1);
for (; l>0; l-=8)
{
if (l >= 8)
{
c2l(in,tin0);
c2l(in,tin1);
}
else
c2ln(in,tin0,tin1,l);
tin0^=tout0; tin[0]=tin0;
tin1^=tout1; tin[1]=tin1;
des_encrypt((DES_LONG *)tin,schedule,DES_ENCRYPT);
tout0=tin[0]; l2c(tout0,out);
tout1=tin[1]; l2c(tout1,out);
}
}
else
{
c2l(iv,xor0);
c2l(iv,xor1);
for (; l>0; l-=8)
{
c2l(in,tin0); tin[0]=tin0;
c2l(in,tin1); tin[1]=tin1;
des_encrypt((DES_LONG *)tin,schedule,DES_DECRYPT);
tout0=tin[0]^xor0;
tout1=tin[1]^xor1;
if (l >= 8)
{
l2c(tout0,out);
l2c(tout1,out);
}
else
l2cn(tout0,tout1,out,l);
xor0=tin0;
xor1=tin1;
}
}
tin0=tin1=tout0=tout1=xor0=xor1=0;
tin[0]=tin[1]=0;
}