/* crypto/des/cfb64enc.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"/* The input and output encrypted as though 64bit cfb mode is being * used.  The extra state information to record how much of the * 64bit block we have used is contained in *num; */void DES_cfb64_encrypt(const unsigned char *in, unsigned char *out,		       long length, DES_key_schedule *schedule,		       DES_cblock *ivec, int *num, int enc)	{	register DES_LONG v0,v1;	register long l=length;	register int n= *num;	DES_LONG ti[2];	unsigned char *iv,c,cc;	iv = &(*ivec)[0];	if (enc)		{		while (l--)			{			if (n == 0)				{				c2l(iv,v0); ti[0]=v0;				c2l(iv,v1); ti[1]=v1;				DES_encrypt1(ti,schedule,DES_ENCRYPT);				iv = &(*ivec)[0];				v0=ti[0]; l2c(v0,iv);				v0=ti[1]; l2c(v0,iv);				iv = &(*ivec)[0];				}			c= *(in++)^iv[n];			*(out++)=c;			iv[n]=c;			n=(n+1)&0x07;			}		}	else		{		while (l--)			{			if (n == 0)				{				c2l(iv,v0); ti[0]=v0;				c2l(iv,v1); ti[1]=v1;				DES_encrypt1(ti,schedule,DES_ENCRYPT);				iv = &(*ivec)[0];				v0=ti[0]; l2c(v0,iv);				v0=ti[1]; l2c(v0,iv);				iv = &(*ivec)[0];				}			cc= *(in++);			c=iv[n];			iv[n]=cc;			*(out++)=c^cc;			n=(n+1)&0x07;			}		}	v0=v1=ti[0]=ti[1]=c=cc=0;	*num=n;	}