/* crypto/des/pcbc_enc.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 "des_locl.h"

 EXPORT_C void DES_pcbc_encrypt(const unsigned char *input, unsigned char *output,

 		      long length, DES_key_schedule *schedule,

 		      DES_cblock *ivec, int enc)

 	{

 	register DES_LONG sin0,sin1,xor0,xor1,tout0,tout1;

 	DES_LONG tin[2];

 	const unsigned char *in;

 	unsigned char *out,*iv;

 	in=input;

 	out=output;

 	iv = &(*ivec)[0];

 	if (enc)

 		{

 		c2l(iv,xor0);

 		c2l(iv,xor1);

 		for (; length>0; length-=8)

 			{

 			if (length >= 8)

 				{

 				c2l(in,sin0);

 				c2l(in,sin1);

 				}

 			else

 				c2ln(in,sin0,sin1,length);

 			tin[0]=sin0^xor0;

 			tin[1]=sin1^xor1;

 			DES_encrypt1((DES_LONG *)tin,schedule,DES_ENCRYPT);

 			tout0=tin[0];

 			tout1=tin[1];

 			xor0=sin0^tout0;

 			xor1=sin1^tout1;

 			l2c(tout0,out);

 			l2c(tout1,out);

 			}

 		}

 	else

 		{

 		c2l(iv,xor0); c2l(iv,xor1);

 		for (; length>0; length-=8)

 			{

 			c2l(in,sin0);

 			c2l(in,sin1);

 			tin[0]=sin0;

 			tin[1]=sin1;

 			DES_encrypt1((DES_LONG *)tin,schedule,DES_DECRYPT);

 			tout0=tin[0]^xor0;

 			tout1=tin[1]^xor1;

 			if (length >= 8)

 				{

 				l2c(tout0,out);

 				l2c(tout1,out);

 				}

 			else

 				l2cn(tout0,tout1,out,length);

 			xor0=tout0^sin0;

 			xor1=tout1^sin1;

 			}

 		}

 	tin[0]=tin[1]=0;

 	sin0=sin1=xor0=xor1=tout0=tout1=0;

 	}