www.pudn.com > miracl.zip > CRGEN.CPP

/* 
 *   Cramer-Shoup Public Key System  
 * 
 *   This program generates one set of public and private keys in files  
 *   public.crs and private.crs respectively 
 * 
 *   Requires: big.cpp 
 * 
 *   Copyright (c) 1999 Shamus Software Ltd. 
 */ 
 
#include  
#include  
#include  
 
using namespace std; 
 
Miracl precision=100; 
 
int main() 
{ 
    ifstream common("common.crs");    // construct file I/O streams  
    ofstream public_key("public.crs"); 
    ofstream private_key("private.crs"); 
    Big p,q,h,g1,g2,x1,x2,y1,y2,z,c,d; 
    int bits; 
    long seed; 
    cout << "Enter 9 digit random number seed  = "; 
    cin >> seed; 
    irand(seed); 
    get_mip()->IOBASE=16; 
 
// get common data  
    common >> bits; 
    common >> q >> p >> g1 >> g2; 
     
// generate public/private keys  
    x1=rand(q); 
    x2=rand(q); 
    y1=rand(q); 
    y2=rand(q); 
    z=rand(q); 
 
    c=pow(g1,x1,g2,x2,p);  // c=g1^x1.g2^x2 mod p 
    d=pow(g1,y1,g2,y2,p); 
    h=pow(g1,z,p); 
 
    private_key << x1 << endl; 
    private_key << x2 << endl; 
    private_key << y1 << endl; 
    private_key << y2 << endl; 
    private_key << z << endl; 
 
    public_key << c << endl; 
    public_key << d << endl; 
    public_key << h << endl; 
 
    return 0; 
}