KGC_TEST/miracl/source/dssgen.c

73 lines
1.5 KiB
C

/*
* Digital Signature Algorithm (DSA)
*
* See Communications ACM July 1992, Vol. 35 No. 7
* This new standard for digital signatures has been proposed by
* the American National Institute of Standards and Technology (NIST)
* under advisement from the National Security Agency (NSA).
*
* This program generates one set of public and private keys in files
* public.dss and private.dss respectively
*
*/
#include <stdio.h>
#include "miracl.h"
int main()
{
FILE *fp;
big p,q,g,x,y;
long seed;
int bits;
miracl *mip;
/* get common data */
fp=fopen("common.dss","rt");
if (fp==NULL)
{
printf("file common.dss does not exist\n");
return 0;
}
fscanf(fp,"%d\n",&bits);
mip=mirsys(bits/4,16); /* use Hex internally */
p=mirvar(0);
q=mirvar(0);
g=mirvar(0);
x=mirvar(0);
y=mirvar(0);
innum(p,fp);
innum(q,fp);
innum(g,fp);
fclose(fp);
/* randomise */
printf("Enter 9 digit random number seed = ");
scanf("%ld",&seed);
getchar();
irand(seed);
powmod(g,q,p,y);
if (size(y)!=1)
{
printf("Problem - generator g is not of order q\n");
return 0;
}
/* generate public/private keys */
bigrand(q,x);
powmod(g,x,p,y);
printf("public key = ");
otnum(y,stdout);
fp=fopen("public.dss","wt");
otnum(y,fp);
fclose(fp);
fp=fopen("private.dss","wt");
otnum(x,fp);
fclose(fp);
mirexit();
return 0;
}