Self-signed #certificate with bouncycastle #java

IngressSpecUtil.java

[...]

import io.fabric8.kubernetes.api.model.Secret;
import io.fabric8.kubernetes.api.model.SecretBuilder;
import org.bouncycastle.asn1.ASN1Encodable;
import org.bouncycastle.asn1.DERSequence;
import org.bouncycastle.asn1.pkcs.PrivateKeyInfo;
import org.bouncycastle.asn1.x509.BasicConstraints;
import org.bouncycastle.asn1.x509.ExtendedKeyUsage;
import org.bouncycastle.asn1.x509.Extension;
import org.bouncycastle.asn1.x509.GeneralName;
import org.bouncycastle.asn1.x509.KeyPurposeId;
import org.bouncycastle.asn1.x509.KeyUsage;
import org.bouncycastle.cert.X509CertificateHolder;
import org.bouncycastle.cert.X509v3CertificateBuilder;
import org.bouncycastle.cert.jcajce.JcaX509v3CertificateBuilder;
import org.bouncycastle.jce.provider.BouncyCastleProvider;
import org.bouncycastle.operator.ContentSigner;
import org.bouncycastle.operator.jcajce.JcaContentSignerBuilder;

/**
 * Holds utility methods to manage Ingress params from specification.
 * @author laurent.broudoux@gmail.com
 */
public class IngressSpecUtil {
  
  /**
    * Generate a Secret holding a self-signed certificate and key for Ingress tests purposes.
    * @param name The name of secret to generate
    * @param labels The labels to add to Secret
    * @param host The host name to generate a cert and key for.
    * @return The created Secret to persist using Kube apis.
    */
   public static Secret generateSelfSignedCertificateSecret(String name, Map<String, String> labels, String host) {
      Security.addProvider(new BouncyCastleProvider());

      X500Principal subject = new X500Principal("CN=" + host);
      X500Principal signedByPrincipal = subject;
      KeyPair keyPair = generateKeyPair();
      KeyPair signedByKeyPair = keyPair;

      long notBefore = System.currentTimeMillis();
      long notAfter = notBefore + (1000L * 3600L * 24 * 365);

      ASN1Encodable[] encodableAltNames = new ASN1Encodable[]{new GeneralName(GeneralName.dNSName, host)};
      KeyPurposeId[] purposes = new KeyPurposeId[]{KeyPurposeId.id_kp_serverAuth, KeyPurposeId.id_kp_clientAuth};

      X509v3CertificateBuilder certBuilder = new JcaX509v3CertificateBuilder(signedByPrincipal,
            BigInteger.ONE, new Date(notBefore), new Date(notAfter), subject, keyPair.getPublic());

      try {
         certBuilder.addExtension(Extension.basicConstraints, true, new BasicConstraints(false));
         certBuilder.addExtension(Extension.keyUsage, true, new KeyUsage(KeyUsage.digitalSignature + KeyUsage.keyEncipherment));
         certBuilder.addExtension(Extension.extendedKeyUsage, false, new ExtendedKeyUsage(purposes));
         certBuilder.addExtension(Extension.subjectAlternativeName, false, new DERSequence(encodableAltNames));

         final ContentSigner signer = new JcaContentSignerBuilder(("SHA256withRSA")).build(signedByKeyPair.getPrivate());
         X509CertificateHolder certHolder = certBuilder.build(signer);

         return new SecretBuilder()
               .withNewMetadata()
                  .withName(name)
                  .addToLabels(labels)
               .endMetadata()
               .withType("kubernetes.io/tls")
               .addToStringData("tls.key", getPrivateKeyPkcs1Pem(keyPair))
               .addToStringData("tls.crt", getCertificatePem(certHolder))
               .build();
      } catch (Exception e) {
         Logger.getLogger(IngressSpecUtil.class).error(e.getMessage());
         throw new AssertionError(e.getMessage());
      }
   }
  
   private static KeyPair generateKeyPair() {
      try {
         KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");
         keyPairGenerator.initialize(2048, new SecureRandom());
         return keyPairGenerator.generateKeyPair();
      } catch (GeneralSecurityException var2) {
         throw new AssertionError(var2);
      }
   }
  
   [...]
}