KGC_TEST/miracl/source/ecsgen.cpp

86 lines
1.9 KiB
C++

/*
* Elliptic Curve Digital Signature Algorithm (ECDSA)
*
*
* This program generates one set of public and private keys in files
* public.ecs and private.ecs respectively. Notice that the public key
* can be much shorter in this scheme, for the same security level.
*
* It is assumed that Curve parameters are to be found in file common.ecs
*
* The curve is y^2=x^3+Ax+B mod p
*
* The file common.ecs is presumed to exist, and to contain the domain
* information {p,A,B,q,x,y}, where A and B are curve parameters, (x,y) are
* a point of order q, p is the prime modulus, and q is the order of the
* point (x,y). In fact normally q is the prime number of points counted
* on the curve.
*
* Requires: big.cpp ecn.cpp
*/
#include <iostream>
#include <fstream>
#include "ecn.h"
using namespace std;
// if MR_STATIC defined, it should be 20
#ifndef MR_NOFULLWIDTH
Miracl precision=20;
#else
Miracl precision(20,MAXBASE);
#endif
int main()
{
ifstream common("common.ecs"); /* construct file I/O streams */
ofstream public_key("public.ecs");
ofstream private_key("private.ecs");
int bits,ep;
miracl *mip=&precision;
ECn G,W;
Big a,b,p,q,x,y,d;
long seed;
cout << "Enter 9 digit random number seed = ";
cin >> seed;
irand(seed);
common >> bits;
mip->IOBASE=16;
common >> p >> a >> b >> q >> x >> y;
mip->IOBASE=10;
ecurve(a,b,p,MR_PROJECTIVE);
if (!G.set(x,y))
{
cout << "Problem - point (x,y) is not on the curve" << endl;
return 0;
}
W=G;
W*=q;
if (!W.iszero())
{
cout << "Problem - point (x,y) is not of order q" << endl;
return 0;
}
/* generate public/private keys */
d=rand(q);
// for (int i=0;i<=10000;i++)
G*=d;
ep=G.get(x);
cout << "public key = " << ep << " " << x << endl;
public_key << ep << " " << x << endl;
private_key << d << endl;
return 0;
}