This is an example of how to generate keys from the DSA Parameters in Java. Using the DSA parameters to generate keys implies that you should:
- Create five BigInteger Objects, to be used as the DSA Parameters, the prime, the subPrime, the base and the private and public keys.
- Create a new KeyFactory for the DSA algorithm.
- Create a DSAPrivateKeySpec, using the private key and the DSA parameters (prime, subprime and base).
- Generate the PrivateKey,using the
generatePrivate(KeySpec keySpec)API method of the KeyFactory, with the DSAPrivateKeySpec. - Create a DSAPublicKeySpec, using the public key and the DSA parameters (prime, subprime and base).
- Generate the PublicKey, using the
generatePublic(KeySpec keySpec)API method of the KeyFactory, with the DSAPublicKeySpec.
Let’s take a look at the code snippet that follows:
package com.javacodegeeks.snippets.core;
import java.math.BigInteger;
import java.security.KeyFactory;
import java.security.NoSuchAlgorithmException;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.spec.DSAPrivateKeySpec;
import java.security.spec.DSAPublicKeySpec;
import java.security.spec.InvalidKeySpecException;
import java.security.spec.KeySpec;
import java.util.Random;
public class GenerateDSAKeys {
public static void main(String[] args) {
try {
Random random = new Random();
/*
* DSA requires three parameters to create a key pair
* prime (P)
* subprime (Q)
* base (G)
* These three values are used to create a private key (X)
* and a public key (Y)
*/
BigInteger prime = new BigInteger(128, random);
BigInteger subPrime = new BigInteger(128, random);
BigInteger base = new BigInteger(128, random);
BigInteger x = new BigInteger(128, random);
BigInteger y = new BigInteger(128, random);
// Get the DSA key factory
KeyFactory keyFactory = KeyFactory.getInstance("DSA");
// Get the private key
KeySpec privateKeySpec = new DSAPrivateKeySpec(x, prime, subPrime, base);
PrivateKey privateKey = keyFactory.generatePrivate(privateKeySpec);
// Get the public key
KeySpec publicKeySpec = new DSAPublicKeySpec(y, prime, subPrime, base);
PublicKey publicKey = keyFactory.generatePublic(publicKeySpec);
System.out.println(privateKey + "n" + publicKey);
} catch (InvalidKeySpecException e) {
} catch (NoSuchAlgorithmException e) {
}
}
}
Example Output:
Sun DSA Private Key
parameters:
p:
07a2730f f524fcba fa29f292 06e5238e
q:
41ea7d7b 0f590de0 4f85fee6 a42da5a9
g:
f2b7cebe 25cc2646 2237ae0c 6daf4a07
x: fba1abf7 a6bdb1cf 2a7c788b e559eb61
Sun DSA Public Key
Parameters:
p:
07a2730f f524fcba fa29f292 06e5238e
q:
41ea7d7b 0f590de0 4f85fee6 a42da5a9
g:
f2b7cebe 25cc2646 2237ae0c 6daf4a07
y:
56326f19 90047fb0 5419e33a 94bf5e55
This was an example of how to generate keys from the DSA Parameters in Java.
Sir, I have copied your code in my netbeans ide and tried running. The code executed with only public key displaying but private key was displayed in below format:
sun.security.provider.DSAPrivateKey@5099a kindly provide how to convert this into meaningful format
Thanx