/* 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"

 EXPORT_C 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;

 	}

 EXPORT_C 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);

 	}

 EXPORT_C 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);

 	}