Java Requires Chilkat v11.0.0+

Generate ECDSA Key and Get Details as XML

See more ECC Examples

Demonstrates how to generate an ECDSA key and gets the parts as XML. Java

import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    boolean success = false;

    //  This requires the Chilkat API to have been previously unlocked.
    //  See Global Unlock Sample for sample code.

    CkEcc ecc = new CkEcc();

    //  Generate a random ECC private key on the secp256k1 curve.
    //  Chilkat also supports other curves, such as secp384r1, secp521r1, and secp256r1.

    //  Create a Fortuna PRNG and seed it with system entropy.
    //  This will be our source of random data for generating the ECC private key.
    CkPrng fortuna = new CkPrng();
    String entropy = fortuna.getEntropy(32,"base64");
    success = fortuna.AddEntropy(entropy,"base64");

    CkPrivateKey privKey = new CkPrivateKey();
    success = ecc.GenKey("secp256k1",fortuna,privKey);
    if (success == false) {
        System.out.println(ecc.lastErrorText());
        return;
        }

    //  An EC private key has this ASN.1
    //  ECPrivateKey ::= SEQUENCE {
    //      version        INTEGER { ecPrivkeyVer1(1) } (ecPrivkeyVer1),
    //      privateKey     OCTET STRING,
    //      parameters [0] ECParameters {{ NamedCurve }} OPTIONAL,
    //      publicKey  [1] BIT STRING OPTIONAL (This is the ANSI X9.63 public key format.)

    CkAsn asn = new CkAsn();
    success = asn.LoadEncoded(privKey.getPkcs1ENC("base64"),"base64");
    if (success != true) {
        System.out.println(asn.lastErrorText());
        return;
        }

    CkXml xml = new CkXml();
    xml.LoadXml(asn.asnToXml());

    System.out.println(xml.getXml());

    //  The XML looks like this:
    //  <?xml version="1.0" encoding="utf-8" ?>
    //  <sequence>
    //      <int>01</int>
    //      <octets>JgJvBG+3wletkJab8iXAkpz0O8/AgWZSpkYVcB7SpnU=</octets>
    //      <contextSpecific tag="0" constructed="1">
    //          <oid>1.3.132.0.10</oid>
    //      </contextSpecific>
    //  </sequence>

    //  The 32-byte private key is in the octets..
    //  Get it as hex.
    CkCrypt2 crypt = new CkCrypt2();
    String privKeyHex = crypt.reEncode(xml.getChildContent("octets"),"base64","hex");

    System.out.println("EC private key as hex = " + privKeyHex);
  }
}