qud_cksm.c revision 296465
1/* crypto/des/qud_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/*
60 * From "Message Authentication" R.R. Jueneman, S.M. Matyas, C.H. Meyer IEEE
61 * Communications Magazine Sept 1985 Vol. 23 No. 9 p 29-40 This module in
62 * only based on the code in this paper and is almost definitely not the same
63 * as the MIT implementation.
64 */
65#include "des_locl.h"
66
67/* bug fix for dos - 7/6/91 - Larry hughes@logos.ucs.indiana.edu */
68#define Q_B0(a) (((DES_LONG)(a)))
69#define Q_B1(a) (((DES_LONG)(a))<<8)
70#define Q_B2(a) (((DES_LONG)(a))<<16)
71#define Q_B3(a) (((DES_LONG)(a))<<24)
72
73/* used to scramble things a bit */
74/* Got the value MIT uses via brute force :-) 2/10/90 eay */
75#define NOISE   ((DES_LONG)83653421L)
76
77DES_LONG DES_quad_cksum(const unsigned char *input, DES_cblock output[],
78                        long length, int out_count, DES_cblock *seed)
79{
80    DES_LONG z0, z1, t0, t1;
81    int i;
82    long l;
83    const unsigned char *cp;
84#ifdef _CRAY
85    struct lp_st {
86        int a:32;
87        int b:32;
88    } *lp;
89#else
90    DES_LONG *lp;
91#endif
92
93    if (out_count < 1)
94        out_count = 1;
95#ifdef _CRAY
96    lp = (struct lp_st *)&(output[0])[0];
97#else
98    lp = (DES_LONG *)&(output[0])[0];
99#endif
100
101    z0 = Q_B0((*seed)[0]) | Q_B1((*seed)[1]) | Q_B2((*seed)[2]) |
102        Q_B3((*seed)[3]);
103    z1 = Q_B0((*seed)[4]) | Q_B1((*seed)[5]) | Q_B2((*seed)[6]) |
104        Q_B3((*seed)[7]);
105
106    for (i = 0; ((i < 4) && (i < out_count)); i++) {
107        cp = input;
108        l = length;
109        while (l > 0) {
110            if (l > 1) {
111                t0 = (DES_LONG)(*(cp++));
112                t0 |= (DES_LONG)Q_B1(*(cp++));
113                l--;
114            } else
115                t0 = (DES_LONG)(*(cp++));
116            l--;
117            /* add */
118            t0 += z0;
119            t0 &= 0xffffffffL;
120            t1 = z1;
121            /* square, well sort of square */
122            z0 = ((((t0 * t0) & 0xffffffffL) + ((t1 * t1) & 0xffffffffL))
123                  & 0xffffffffL) % 0x7fffffffL;
124            z1 = ((t0 * ((t1 + NOISE) & 0xffffffffL)) & 0xffffffffL) %
125                0x7fffffffL;
126        }
127        if (lp != NULL) {
128            /*
129             * The MIT library assumes that the checksum is composed of
130             * 2*out_count 32 bit ints
131             */
132#ifdef _CRAY
133            (*lp).a = z0;
134            (*lp).b = z1;
135            lp++;
136#else
137            *lp++ = z0;
138            *lp++ = z1;
139#endif
140        }
141    }
142    return (z0);
143}
144