/* crypto/rc2/rc2_cbc.c */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
* All rights reserved.
*
* This package is an SSL implementation written
* by Eric Young (eay@cryptsoft.com).
* The implementation was written so as to conform with Netscapes SSL.
*
* This library is free for commercial and non-commercial use as long as
* the following conditions are aheared to. The following conditions
* apply to all code found in this distribution, be it the RC4, RSA,
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
* included with this distribution is covered by the same copyright terms
* except that the holder is Tim Hudson (tjh@cryptsoft.com).
*
* Copyright remains Eric Young's, and as such any Copyright notices in
* the code are not to be removed.
* If this package is used in a product, Eric Young should be given attribution
* as the author of the parts of the library 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 cryptographic software written by
* Eric Young (eay@cryptsoft.com)"
* The word 'cryptographic' can be left out if the rouines from the library
* being used are not cryptographic related :-).
* 4. If you include any Windows specific code (or a derivative thereof) from
* the apps directory (application code) you must include an acknowledgement:
* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
*
* 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 <openssl/rc2.h>
#include "rc2_locl.h"
void RC2_cbc_encrypt(const unsigned char *in, unsigned char *out, long length,
RC2_KEY *ks, unsigned char *iv, int encrypt)
{
register unsigned long tin0,tin1;
register unsigned long tout0,tout1,xor0,xor1;
register long l=length;
unsigned long tin[2];
if (encrypt)
{
c2l(iv,tout0);
c2l(iv,tout1);
iv-=8;
for (l-=8; l>=0; l-=8)
{
c2l(in,tin0);
c2l(in,tin1);
tin0^=tout0;
tin1^=tout1;
tin[0]=tin0;
tin[1]=tin1;
RC2_encrypt(tin,ks);
tout0=tin[0]; l2c(tout0,out);
tout1=tin[1]; l2c(tout1,out);
}
if (l != -8)
{
c2ln(in,tin0,tin1,l+8);
tin0^=tout0;
tin1^=tout1;
tin[0]=tin0;
tin[1]=tin1;
RC2_encrypt(tin,ks);
tout0=tin[0]; l2c(tout0,out);
tout1=tin[1]; l2c(tout1,out);
}
l2c(tout0,iv);
l2c(tout1,iv);
}
else
{
c2l(iv,xor0);
c2l(iv,xor1);
iv-=8;
for (l-=8; l>=0; l-=8)
{
c2l(in,tin0); tin[0]=tin0;
c2l(in,tin1); tin[1]=tin1;
RC2_decrypt(tin,ks);
tout0=tin[0]^xor0;
tout1=tin[1]^xor1;
l2c(tout0,out);
l2c(tout1,out);
xor0=tin0;
xor1=tin1;
}
if (l != -8)
{
c2l(in,tin0); tin[0]=tin0;
c2l(in,tin1); tin[1]=tin1;
RC2_decrypt(tin,ks);
tout0=tin[0]^xor0;
tout1=tin[1]^xor1;
l2cn(tout0,tout1,out,l+8);
xor0=tin0;
xor1=tin1;
}
l2c(xor0,iv);
l2c(xor1,iv);
}
tin0=tin1=tout0=tout1=xor0=xor1=0;
tin[0]=tin[1]=0;
}
void RC2_encrypt(unsigned long *d, RC2_KEY *key)
{
int i,n;
register RC2_INT *p0,*p1;
register RC2_INT x0,x1,x2,x3,t;
unsigned long l;
l=d[0];
x0=(RC2_INT)l&0xffff;
x1=(RC2_INT)(l>>16L);
l=d[1];
x2=(RC2_INT)l&0xffff;
x3=(RC2_INT)(l>>16L);
n=3;
i=5;
p0=p1= &(key->data[0]);
for (;;)
{
t=(x0+(x1& ~x3)+(x2&x3)+ *(p0++))&0xffff;
x0=(t<<1)|(t>>15);
t=(x1+(x2& ~x0)+(x3&x0)+ *(p0++))&0xffff;
x1=(t<<2)|(t>>14);
t=(x2+(x3& ~x1)+(x0&x1)+ *(p0++))&0xffff;
x2=(t<<3)|(t>>13);
t=(x3+(x0& ~x2)+(x1&x2)+ *(p0++))&0xffff;
x3=(t<<5)|(t>>11);
if (--i == 0)
{
if (--n == 0) break;
i=(n == 2)?6:5;
x0+=p1[x3&0x3f];
x1+=p1[x0&0x3f];
x2+=p1[x1&0x3f];
x3+=p1[x2&0x3f];
}
}
d[0]=(unsigned long)(x0&0xffff)|((unsigned long)(x1&0xffff)<<16L);
d[1]=(unsigned long)(x2&0xffff)|((unsigned long)(x3&0xffff)<<16L);
}
void RC2_decrypt(unsigned long *d, RC2_KEY *key)
{
int i,n;
register RC2_INT *p0,*p1;
register RC2_INT x0,x1,x2,x3,t;
unsigned long l;
l=d[0];
x0=(RC2_INT)l&0xffff;
x1=(RC2_INT)(l>>16L);
l=d[1];
x2=(RC2_INT)l&0xffff;
x3=(RC2_INT)(l>>16L);
n=3;
i=5;
p0= &(key->data[63]);
p1= &(key->data[0]);
for (;;)
{
t=((x3<<11)|(x3>>5))&0xffff;
x3=(t-(x0& ~x2)-(x1&x2)- *(p0--))&0xffff;
t=((x2<<13)|(x2>>3))&0xffff;
x2=(t-(x3& ~x1)-(x0&x1)- *(p0--))&0xffff;
t=((x1<<14)|(x1>>2))&0xffff;
x1=(t-(x2& ~x0)-(x3&x0)- *(p0--))&0xffff;
t=((x0<<15)|(x0>>1))&0xffff;
x0=(t-(x1& ~x3)-(x2&x3)- *(p0--))&0xffff;
if (--i == 0)
{
if (--n == 0) break;
i=(n == 2)?6:5;
x3=(x3-p1[x2&0x3f])&0xffff;
x2=(x2-p1[x1&0x3f])&0xffff;
x1=(x1-p1[x0&0x3f])&0xffff;
x0=(x0-p1[x3&0x3f])&0xffff;
}
}
d[0]=(unsigned long)(x0&0xffff)|((unsigned long)(x1&0xffff)<<16L);
d[1]=(unsigned long)(x2&0xffff)|((unsigned long)(x3&0xffff)<<16L);
}