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Java

Generate new DSA Key from OpenSSL Parameters File

See more DSA Examples

Generates a new DSA key from an OpenSSL-created parameters file (DER and PEM formats supported). Examples of using OpenSSL to create parameter files are shown here:
openssl dsaparam -outform DER 1024 <  seedData.txt >dsaparam.der

openssl dsaparam 1024 < seedData.txt >dsaparam.pem

Chilkat Java Downloads

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

    CkDsa dsa = new CkDsa();

    success = dsa.GenKeyFromParamsDerFile("dsaparam.der");
    if (success != true) {
        System.out.println(dsa.lastErrorText());
        return;
        }

    // To generate a key from PEM, call GenKeyFromParamsPem 
    // (for an in-memory PEM string) or GenKeyFromParamsFilePem
    // for a PEM file.

    // The public and private keys may now be exported to PEM, DER,
    // and XML formatted files.

    String pemStr;
    String xmlStr;

    // First for the public key...
    // The public key never needs to be encrypted.

    // Save the public key in PEM format:
    pemStr = dsa.toPublicPem();
    // This example will not check the return value of SaveText...
    success = dsa.SaveText(pemStr,"dsa_pub.pem");

    // Save the public key in DER format:
    success = dsa.ToPublicDerFile("dsa_pub.der");

    boolean bPublicOnly = true;
    // Save to XML
    xmlStr = dsa.toXml(bPublicOnly);
    success = dsa.SaveText(pemStr,"dsa_pub.xml");

    // ------------------------------------
    // Now for the private key....
    // ------------------------------------

    // Unencrypted PEM:
    pemStr = dsa.toPem();
    success = dsa.SaveText(pemStr,"dsa_priv.pem");

    // Encrypted PEM:
    pemStr = dsa.toEncryptedPem("myPassword");
    success = dsa.SaveText(pemStr,"dsa_privEncrypted.pem");

    // DER:
    success = dsa.ToDerFile("dsa_priv.der");

    // XML:
    bPublicOnly = false;
    xmlStr = dsa.toXml(bPublicOnly);
    success = dsa.SaveText(pemStr,"dsa_priv.xml");

    System.out.println("Finished!");
  }
}