(Java) Generate RSA Key and Export to PKCS1 / PKCS8

Java example code showing how to generate an RSA public/private key and save to PKCS1 and PKCS8 format files. In a PKCS1 or PKCS8 formatted file, the key is stored in binary ASN.1 format (and ASN.1 is itself written according to DER -- Distinguished Encoding Rules). A PEM file simply contains the binary ASN.1 base64 encoded and delimited by BEGIN/END lines. PKCS1 format files are never encrypted. PKCS8 can be encrypted or unencrypted. Public keys are never encrypted (there is no need). Private keys *should* always be encrypted - unless perhaps the unencrypted private key is obtained and itself stored in some sort of secure place.

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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[])
  {
    // This example assumes the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    CkRsa rsa = new CkRsa();

    // Generate a 2048-bit key.  Chilkat RSA supports
    // key sizes ranging from 512 bits to 8192 bits.
    boolean success = rsa.GenerateKey(2048);
    if (success != true) {
        System.out.println(rsa.lastErrorText());
        return;
        }

    // Get the public and private key parts:
    CkPublicKey pubKey = rsa.ExportPublicKeyObj();
    CkPrivateKey privKey = rsa.ExportPrivateKeyObj();

    // Get the public key as a PKCS8 PEM string
    String pubKeyPem = pubKey.getPem(false);
    System.out.println(pubKeyPem);

    // Get the public key in PKCS8 format, in a Base64 encoded string.
    String pubKeyPkcs8Base64 = pubKey.getEncoded(false,"base64");
    System.out.println(pubKeyPkcs8Base64);

    // Get the public key in PKCS1 format, in a Base64 encoded string.
    String pubKeyPkcs1Base64 = pubKey.getEncoded(true,"base64");
    System.out.println(pubKeyPkcs1Base64);

    // Get the private key in a PKCS8 PEM string.
    String privKeyPem = privKey.getPkcs8Pem();
    System.out.println(privKeyPem);

    // Get the private key in a PKCS8 encrypted PEM string.
    String privKeyEncPem = privKey.getPkcs8EncryptedPem("myPassword");
    System.out.println(privKeyEncPem);

    // Get the private key in PKCS1 Base64 format
    String privKeyPkcs1Base64 = privKey.getPkcs1ENC("base64");
    System.out.println(privKeyPkcs1Base64);

    // Get the private key in PKCS8 Base64 format
    String privKeyPkcs8Base64 = privKey.getPkcs8ENC("base64");
    System.out.println(privKeyPkcs8Base64);

    // Save to PKCS1 / PKCS8 / PEM files...

    // Save the public key to PKCS8 binary DER
    success = pubKey.SaveDerFile(false,"pubKey_pkcs8.der");

    // Save the public key to PKCS1 binary DER
    success = pubKey.SaveDerFile("pubKey_pkcs1.der");

    // Save the private key to unencrypted binary PKCS1 DER.
    // Note: PKCS1 is never found in an encrypted format. 
    success = privKey.SavePkcs1File("privKey_pkcs1.der");

    // Save the private key to unencrypted binary PKCS8
    success = privKey.SavePkcs8File("privKey_pkcs8.der");

    // Save the private key to encrypted binary PKCS8
    success = privKey.SavePkcs8EncryptedFile("myPassword","privKey_enc_pkcs8.der");

    // Save the private key to unencrypted PKCS8 PEM
    success = privKey.SavePkcs8PemFile("privKey.pem");

    // Save the private key to encrypted PKCS8 PEM
    success = privKey.SavePkcs8EncryptedPemFile("myPassword","privKey_enc.pem");
  }
}