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bf_cbc.c revision 1.6 
      1 /* crypto/bf/bf_cbc.c */
      2 /* Copyright (C) 1995-1998 Eric Young (eay (at) cryptsoft.com)
      3  * All rights reserved.
      4  *
      5  * This package is an SSL implementation written
      6  * by Eric Young (eay (at) cryptsoft.com).
      7  * The implementation was written so as to conform with Netscapes SSL.
      8  *
      9  * This library is free for commercial and non-commercial use as long as
     10  * the following conditions are aheared to.  The following conditions
     11  * apply to all code found in this distribution, be it the RC4, RSA,
     12  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
     13  * included with this distribution is covered by the same copyright terms
     14  * except that the holder is Tim Hudson (tjh (at) cryptsoft.com).
     15  *
     16  * Copyright remains Eric Young's, and as such any Copyright notices in
     17  * the code are not to be removed.
     18  * If this package is used in a product, Eric Young should be given attribution
     19  * as the author of the parts of the library used.
     20  * This can be in the form of a textual message at program startup or
     21  * in documentation (online or textual) provided with the package.
     22  *
     23  * Redistribution and use in source and binary forms, with or without
     24  * modification, are permitted provided that the following conditions
     25  * are met:
     26  * 1. Redistributions of source code must retain the copyright
     27  *    notice, this list of conditions and the following disclaimer.
     28  * 2. Redistributions in binary form must reproduce the above copyright
     29  *    notice, this list of conditions and the following disclaimer in the
     30  *    documentation and/or other materials provided with the distribution.
     31  * 3. All advertising materials mentioning features or use of this software
     32  *    must display the following acknowledgement:
     33  *    "This product includes cryptographic software written by
     34  *     Eric Young (eay (at) cryptsoft.com)"
     35  *    The word 'cryptographic' can be left out if the rouines from the library
     36  *    being used are not cryptographic related :-).
     37  * 4. If you include any Windows specific code (or a derivative thereof) from
     38  *    the apps directory (application code) you must include an acknowledgement:
     39  *    "This product includes software written by Tim Hudson (tjh (at) cryptsoft.com)"
     40  *
     41  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
     42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
     45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     51  * SUCH DAMAGE.
     52  *
     53  * The licence and distribution terms for any publically available version or
     54  * derivative of this code cannot be changed.  i.e. this code cannot simply be
     55  * copied and put under another distribution licence
     56  * [including the GNU Public Licence.]
     57  */
     58 
     59 #include <sys/cdefs.h>
     60 __KERNEL_RCSID(0, "$NetBSD: bf_cbc.c,v 1.6 2002/09/07 22:58:04 elric Exp $");
     61 
     62 #include <crypto/blowfish/blowfish.h>
     63 #include "bf_locl.h"
     64 
     65 void BF_cbc_encrypt(const unsigned char *in, unsigned char *out, long length,
     66 	     const BF_KEY *schedule, unsigned char *ivec, int encrypt)
     67 	{
     68 	register BF_LONG tin0,tin1;
     69 	register BF_LONG tout0,tout1,xor0,xor1;
     70 	register long l=length;
     71 	BF_LONG tin[2];
     72 
     73 	if (encrypt)
     74 		{
     75 		n2l(ivec,tout0);
     76 		n2l(ivec,tout1);
     77 		ivec-=8;
     78 		for (l-=8; l>=0; l-=8)
     79 			{
     80 			n2l(in,tin0);
     81 			n2l(in,tin1);
     82 			tin0^=tout0;
     83 			tin1^=tout1;
     84 			tin[0]=tin0;
     85 			tin[1]=tin1;
     86 			BF_encrypt(tin,schedule);
     87 			tout0=tin[0];
     88 			tout1=tin[1];
     89 			l2n(tout0,out);
     90 			l2n(tout1,out);
     91 			}
     92 		if (l != -8)
     93 			{
     94 			n2ln(in,tin0,tin1,l+8);
     95 			tin0^=tout0;
     96 			tin1^=tout1;
     97 			tin[0]=tin0;
     98 			tin[1]=tin1;
     99 			BF_encrypt(tin,schedule);
    100 			tout0=tin[0];
    101 			tout1=tin[1];
    102 			l2n(tout0,out);
    103 			l2n(tout1,out);
    104 			}
    105 		l2n(tout0,ivec);
    106 		l2n(tout1,ivec);
    107 		}
    108 	else
    109 		{
    110 		n2l(ivec,xor0);
    111 		n2l(ivec,xor1);
    112 		ivec-=8;
    113 		for (l-=8; l>=0; l-=8)
    114 			{
    115 			n2l(in,tin0);
    116 			n2l(in,tin1);
    117 			tin[0]=tin0;
    118 			tin[1]=tin1;
    119 			BF_decrypt(tin,schedule);
    120 			tout0=tin[0]^xor0;
    121 			tout1=tin[1]^xor1;
    122 			l2n(tout0,out);
    123 			l2n(tout1,out);
    124 			xor0=tin0;
    125 			xor1=tin1;
    126 			}
    127 		if (l != -8)
    128 			{
    129 			n2l(in,tin0);
    130 			n2l(in,tin1);
    131 			tin[0]=tin0;
    132 			tin[1]=tin1;
    133 			BF_decrypt(tin,schedule);
    134 			tout0=tin[0]^xor0;
    135 			tout1=tin[1]^xor1;
    136 			l2nn(tout0,tout1,out,l+8);
    137 			xor0=tin0;
    138 			xor1=tin1;
    139 			}
    140 		l2n(xor0,ivec);
    141 		l2n(xor1,ivec);
    142 		}
    143 	tin0=tin1=tout0=tout1=xor0=xor1=0;
    144 	tin[0]=tin[1]=0;
    145 	}
    146 
    147