www.pudn.com > truecrypt-4.2-source-code.zip > Bf_enc.c


/* crypto/bf/bf_enc.c */ 
/* Copyright (C) 1995-1997 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.] 
 */ 
 
 
#pragma warning( disable : 4131 ) 
 
 
#include "Blowfish.h" 
#include "Bf_locl.h" 
 
/* Blowfish as implemented from 'Blowfish: Springer-Verlag paper' 
 * (From LECTURE NOTES IN COIMPUTER SCIENCE 809, FAST SOFTWARE ENCRYPTION, 
 * CAMBRIDGE SECURITY WORKSHOP, CAMBRIDGE, U.K., DECEMBER 9-11, 1993) 
 */ 
 
#if (BF_ROUNDS != 16) && (BF_ROUNDS != 20) 
If you set BF_ROUNDS to some value other than 16 or 20, you will have 
to modify the code. 
#endif 
 
void BF_encrypt(data,key) 
BF_LONG *data; 
BF_KEY *key; 
	{ 
	register BF_LONG l,r,*p,*s; 
 
	p=key->P; 
	s= &(key->S[0]); 
	l=data[0]; 
	r=data[1]; 
 
	l^=p[0]; 
	BF_ENC(r,l,s,p[ 1]); 
	BF_ENC(l,r,s,p[ 2]); 
	BF_ENC(r,l,s,p[ 3]); 
	BF_ENC(l,r,s,p[ 4]); 
	BF_ENC(r,l,s,p[ 5]); 
	BF_ENC(l,r,s,p[ 6]); 
	BF_ENC(r,l,s,p[ 7]); 
	BF_ENC(l,r,s,p[ 8]); 
	BF_ENC(r,l,s,p[ 9]); 
	BF_ENC(l,r,s,p[10]); 
	BF_ENC(r,l,s,p[11]); 
	BF_ENC(l,r,s,p[12]); 
	BF_ENC(r,l,s,p[13]); 
	BF_ENC(l,r,s,p[14]); 
	BF_ENC(r,l,s,p[15]); 
	BF_ENC(l,r,s,p[16]); 
#if BF_ROUNDS == 20 
	BF_ENC(r,l,s,p[17]); 
	BF_ENC(l,r,s,p[18]); 
	BF_ENC(r,l,s,p[19]); 
	BF_ENC(l,r,s,p[20]); 
#endif 
	r^=p[BF_ROUNDS+1]; 
 
	data[1]=l&0xffffffffL; 
	data[0]=r&0xffffffffL; 
	} 
 
#ifndef BF_DEFAULT_OPTIONS 
 
void BF_decrypt(data,key) 
BF_LONG *data; 
BF_KEY *key; 
	{ 
	register BF_LONG l,r,*p,*s; 
 
	p=key->P; 
	s= &(key->S[0]); 
	l=data[0]; 
	r=data[1]; 
 
	l^=p[BF_ROUNDS+1]; 
#if BF_ROUNDS == 20 
	BF_ENC(r,l,s,p[20]); 
	BF_ENC(l,r,s,p[19]); 
	BF_ENC(r,l,s,p[18]); 
	BF_ENC(l,r,s,p[17]); 
#endif 
	BF_ENC(r,l,s,p[16]); 
	BF_ENC(l,r,s,p[15]); 
	BF_ENC(r,l,s,p[14]); 
	BF_ENC(l,r,s,p[13]); 
	BF_ENC(r,l,s,p[12]); 
	BF_ENC(l,r,s,p[11]); 
	BF_ENC(r,l,s,p[10]); 
	BF_ENC(l,r,s,p[ 9]); 
	BF_ENC(r,l,s,p[ 8]); 
	BF_ENC(l,r,s,p[ 7]); 
	BF_ENC(r,l,s,p[ 6]); 
	BF_ENC(l,r,s,p[ 5]); 
	BF_ENC(r,l,s,p[ 4]); 
	BF_ENC(l,r,s,p[ 3]); 
	BF_ENC(r,l,s,p[ 2]); 
	BF_ENC(l,r,s,p[ 1]); 
	r^=p[0]; 
 
	data[1]=l&0xffffffffL; 
	data[0]=r&0xffffffffL; 
	} 
 
void BF_cbc_encrypt(in, out, length, ks, iv, encrypt) 
unsigned char *in; 
unsigned char *out; 
long length; 
BF_KEY *ks; 
unsigned char *iv; 
int encrypt; 
	{ 
	register BF_LONG tin0,tin1; 
	register BF_LONG tout0,tout1,xor0,xor1; 
	register long l=length; 
	BF_LONG tin[2]; 
 
	if (encrypt) 
		{ 
		n2l(iv,tout0); 
		n2l(iv,tout1); 
		iv-=8; 
		for (l-=8; l>=0; l-=8) 
			{ 
			n2l(in,tin0); 
			n2l(in,tin1); 
			tin0^=tout0; 
			tin1^=tout1; 
			tin[0]=tin0; 
			tin[1]=tin1; 
			BF_encrypt(tin,ks); 
			tout0=tin[0]; 
			tout1=tin[1]; 
			l2n(tout0,out); 
			l2n(tout1,out); 
			} 
		if (l != -8) 
			{ 
			n2ln(in,tin0,tin1,l+8); 
			tin0^=tout0; 
			tin1^=tout1; 
			tin[0]=tin0; 
			tin[1]=tin1; 
			BF_encrypt(tin,ks); 
			tout0=tin[0]; 
			tout1=tin[1]; 
			l2n(tout0,out); 
			l2n(tout1,out); 
			} 
		l2n(tout0,iv); 
		l2n(tout1,iv); 
		} 
	else 
		{ 
		n2l(iv,xor0); 
		n2l(iv,xor1); 
		iv-=8; 
		for (l-=8; l>=0; l-=8) 
			{ 
			n2l(in,tin0); 
			n2l(in,tin1); 
			tin[0]=tin0; 
			tin[1]=tin1; 
			BF_decrypt(tin,ks); 
			tout0=tin[0]^xor0; 
			tout1=tin[1]^xor1; 
			l2n(tout0,out); 
			l2n(tout1,out); 
			xor0=tin0; 
			xor1=tin1; 
			} 
		if (l != -8) 
			{ 
			n2l(in,tin0); 
			n2l(in,tin1); 
			tin[0]=tin0; 
			tin[1]=tin1; 
			BF_decrypt(tin,ks); 
			tout0=tin[0]^xor0; 
			tout1=tin[1]^xor1; 
			l2nn(tout0,tout1,out,l+8); 
			xor0=tin0; 
			xor1=tin1; 
			} 
		l2n(xor0,iv); 
		l2n(xor1,iv); 
		} 
	tin0=tin1=tout0=tout1=xor0=xor1=0; 
	tin[0]=tin[1]=0; 
	} 
 
#endif