cbc_cksm.c revision 111147 
1/* crypto/des/cbc_cksm.c */
2/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3 * All rights reserved.
4 *
5 * This package is an SSL implementation written
6 * by Eric Young (eay@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@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@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@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 "des_locl.h"
60
61DES_LONG DES_cbc_cksum(const unsigned char *in, DES_cblock *output,
62		       long length, DES_key_schedule *schedule,
63		       const_DES_cblock *ivec)
64	{
65	register DES_LONG tout0,tout1,tin0,tin1;
66	register long l=length;
67	DES_LONG tin[2];
68	unsigned char *out = &(*output)[0];
69	const unsigned char *iv = &(*ivec)[0];
70
71	c2l(iv,tout0);
72	c2l(iv,tout1);
73	for (; l>0; l-=8)
74		{
75		if (l >= 8)
76			{
77			c2l(in,tin0);
78			c2l(in,tin1);
79			}
80		else
81			c2ln(in,tin0,tin1,l);
82
83		tin0^=tout0; tin[0]=tin0;
84		tin1^=tout1; tin[1]=tin1;
85		DES_encrypt1((DES_LONG *)tin,schedule,DES_ENCRYPT);
86		/* fix 15/10/91 eay - thanks to keithr@sco.COM */
87		tout0=tin[0];
88		tout1=tin[1];
89		}
90	if (out != NULL)
91		{
92		l2c(tout0,out);
93		l2c(tout1,out);
94		}
95	tout0=tin0=tin1=tin[0]=tin[1]=0;
96	/*
97	  Transform the data in tout1 so that it will
98	  match the return value that the MIT Kerberos
99	  mit_des_cbc_cksum API returns.
100	*/
101	tout1 = ((tout1 >> 24L) & 0x000000FF)
102	      | ((tout1 >> 8L)  & 0x0000FF00)
103	      | ((tout1 << 8L)  & 0x00FF0000)
104	      | ((tout1 << 24L) & 0xFF000000);
105	return(tout1);
106	}
107