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