/* crypto/rc2/rc2ofb64.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"

 /* The input and output encrypted as though 64bit ofb mode is being

  * used.  The extra state information to record how much of the

  * 64bit block we have used is contained in *num;

  */

 EXPORT_C void RC2_ofb64_encrypt(const unsigned char *in, unsigned char *out,

 		       long length, RC2_KEY *schedule, unsigned char *ivec,

 		       int *num)

 	{

 	register unsigned long v0,v1,t;

 	register int n= *num;

 	register long l=length;

 	unsigned char d[8];

 	register char *dp;

 	unsigned long ti[2];

 	unsigned char *iv;

 	int save=0;

 	iv=(unsigned char *)ivec;

 	c2l(iv,v0);

 	c2l(iv,v1);

 	ti[0]=v0;

 	ti[1]=v1;

 	dp=(char *)d;

 	l2c(v0,dp);

 	l2c(v1,dp);

 	while (l--)

 		{

 		if (n == 0)

 			{

 			RC2_encrypt((unsigned long *)ti,schedule);

 			dp=(char *)d;

 			t=ti[0]; l2c(t,dp);

 			t=ti[1]; l2c(t,dp);

 			save++;

 			}

 		*(out++)= *(in++)^d[n];

 		n=(n+1)&0x07;

 		}

 	if (save)

 		{

 		v0=ti[0];

 		v1=ti[1];

 		iv=(unsigned char *)ivec;

 		l2c(v0,iv);

 		l2c(v1,iv);

 		}

 	t=v0=v1=ti[0]=ti[1]=0;

 	*num=n;

 	}