(Java) Generate CSR from Pre-Existing Private Key

Demonstrates how to generate a Certificate Signing Request (CSR) from a pre-existing RSA private key.

Note: This example requires Chilkat v9.5.0.65 or greater.

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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[])
  {
    // Note: Requires Chilkat v9.5.0.65 or greater.

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

    CkPrivateKey privKey = new CkPrivateKey();

    // Load the private key from a file.
    // (Chilkat provides the ability to load private keys from many different
    // formats and sources..)
    boolean success = privKey.LoadEncryptedPemFile("qa_data/rsa/privKey1.pem","password");
    if (!success) {
        System.out.println(privKey.lastErrorText());
        return;
        }

    // Create the CSR object and set properties.
    CkCsr csr = new CkCsr();

    // Specify the Common Name.  This is the only required property.
    // For SSL/TLS certificates, this would be the domain name. 
    // For email certificates this would be the email address. 
    csr.put_CommonName("mysubdomain.mydomain.com");

    // Country Name (2 letter code)
    csr.put_Country("GB");

    // State or Province Name (full name)
    csr.put_State("Yorks");

    // Locality Name (eg, city)
    csr.put_Locality("York");

    // Organization Name (eg, company)
    csr.put_Company("Internet Widgits Pty Ltd");

    // Organizational Unit Name (eg, secion/division)
    csr.put_CompanyDivision("IT");

    // Email address
    csr.put_EmailAddress("support@mydomain.com");

    // Create the CSR using the private key.
    String pemStr = csr.genCsrPem(privKey);
    if (csr.get_LastMethodSuccess() != true) {
        System.out.println(csr.lastErrorText());
        return;
        }

    // Save the CSR..
    CkFileAccess fac = new CkFileAccess();
    fac.WriteEntireTextFile("qa_output/csr1.pem",pemStr,"utf-8",false);

    // Show the CSR.
    System.out.println(pemStr);

    // Sample output:
    // The CSR PEM can be checked here:
    // https://www.networking4all.com/en/support/tools/csr+check/
    // Copy-and-paste the PEM into the online CSR Decoding / CSR Verification form

    // 	-----BEGIN CERTIFICATE REQUEST-----
    // 	MIIC6jCCAdICAQAwgaQxITAfBgNVBAMMGG15c3ViZG9tYWluLm15ZG9tYWluLmNv
    // 	bTELMAkGA1UEBhMCR0IxDjAMBgNVBAgMBVlvcmtzMQ0wCwYDVQQHDARZb3JrMSEw
    // 	HwYDVQQKDBhJbnRlcm5ldCBXaWRnaXRzIFB0eSBMdGQxCzAJBgNVBAsMAklUMSMw
    // 	IQYJKoZIhvcNAQkBFhRzdXBwb3J0QG15ZG9tYWluLmNvbTCCASIwDQYJKoZIhvcN
    // 	AQEBBQADggEPADCCAQoCggEBALnQ0un/wF8whk+gPuiAlf3qvx14jgAOV6Erm6EB
    // 	H7WACPCpnKcm/8KP+7uoPiwRQaENhMeCgf45vcivl2p6aAn/spLXyEkXyw2d8wFb
    // 	YYAGRkiz4Xf7ASJiKuwcOtORz+sSDzgtdfokHfXU1cYeFE2yQhSdLUY5fMn425+g
    // 	KoEEsRSjSDe6AKru4+4iGNrLKd8pB9IA5/jOE139IkWlB9r5fEPD5bUTsgqXk9eb
    // 	68O0gc712V2eZK07N24lDmFC4bIMTD4csDWocR5hFHXj7NX7c8sOBDcpEb9mPIk4
    // 	elxubnhkfnjhOi4J3lDHcT/0ALnbLhf9LnaiKqs+5VcVZvECAwEAAaAAMA0GCSqG
    // 	SIb3DQEBBQUAA4IBAQC0AETLIcP3foh5nbu2hVFS8uCUNZ5hEIR1eXmYZmZoBQq2
    // 	26ZAoT4CZwixlggC+n7WvAXJ5Pzxpl4wLV4loTiQzaKPX1w0ERo5ZRwLy0n56oG2
    // 	6QG+WTViT1C8rlgtVwkCFNOXr0kSSRs8FdaPllqKxK1hxYSL7zwNpumsk39F2cDt
    // 	vhcekvH0V3BuGrQFm3dKN/0azW6GOod9+Vq4VzSyOe3kp15oxLBsZOFOu/REujcw
    // 	Tzu2jt1asQKUm60CZ9wNHpYepR0Ww40uP1slbehEaFDa6V8b60/tlHHmBbJ4/fy5
    // 	hJnYCvjzFz4O9VtT+JtP9ldRHWV3KpZ8ne3AjD+F
    // 	-----END CERTIFICATE REQUEST-----
  }
}