/* crypto/des/cfb64enc.c */ /* Copyright (C) 1995-1996 Eric Young (eay@mincom.oz.au) * All rights reserved. * * This file is part of an SSL implementation written * by Eric Young (eay@mincom.oz.au). * The implementation was written so as to conform with Netscapes SSL * specification. This library and applications are * FREE FOR COMMERCIAL AND NON-COMMERCIAL USE * as long as the following conditions are aheared to. * * Copyright remains Eric Young's, and as such any Copyright notices in * the code are not to be removed. If this code is used in a product, * Eric Young should be given attribution as the author of the parts 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 software developed by Eric Young (eay@mincom.oz.au) * * 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(in, out, length, schedule, ivec, num, encrypt) unsigned char *in; unsigned char *out; long length; des_key_schedule schedule; des_cblock (*ivec); int *num; int encrypt; { register DES_LONG v0,v1; register long l=length; register int n= *num; DES_LONG ti[2]; unsigned char *iv,c,cc; iv=(unsigned char *)ivec; if (encrypt) { while (l--) { if (n == 0) { c2l(iv,v0); ti[0]=v0; c2l(iv,v1); ti[1]=v1; des_encrypt((DES_LONG *)ti, schedule,DES_ENCRYPT); iv=(unsigned char *)ivec; v0=ti[0]; l2c(v0,iv); v0=ti[1]; l2c(v0,iv); iv=(unsigned char *)ivec; } 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_encrypt((DES_LONG *)ti, schedule,DES_ENCRYPT); iv=(unsigned char *)ivec; v0=ti[0]; l2c(v0,iv); v0=ti[1]; l2c(v0,iv); iv=(unsigned char *)ivec; } 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; }