public static CertificateKeyPair generateCertificate()

in plc4j/tools/opcua-server/src/main/java/org/apache/plc4x/java/opcuaserver/context/CertificateGenerator.java [54:126]
57 lines of code
3 McCabe index (conditional complexity)

    public static CertificateKeyPair generateCertificate() {
        KeyPairGenerator kpg = null;
        try {
            kpg = KeyPairGenerator.getInstance("RSA");
        } catch (NoSuchAlgorithmException e) {
            LOGGER.error("Security Algorithm is unsupported for certificate");
            return null;
        }
        kpg.initialize(2048);
        KeyPair caKeys = kpg.generateKeyPair();
        KeyPair userKeys = kpg.generateKeyPair();

        X500NameBuilder nameBuilder = new X500NameBuilder();

        nameBuilder.addRDN(BCStyle.CN, "Apache PLC4X Driver Client");
        nameBuilder.addRDN(BCStyle.O, "Apache Software Foundation");
        nameBuilder.addRDN(BCStyle.OU, "dev");
        nameBuilder.addRDN(BCStyle.L, "");
        nameBuilder.addRDN(BCStyle.ST, "DE");
        nameBuilder.addRDN(BCStyle.C, "US");

        byte[] bytes = new byte[40];
        new SecureRandom().nextBytes(bytes);
        BigInteger serial = new BigInteger(bytes);

        final Calendar calender = Calendar.getInstance();
        calender.add(Calendar.DATE, -1);
        Date startDate = calender.getTime();
        calender.add(Calendar.DATE, 365 * 25);
        Date expiryDate = calender.getTime();

        KeyPairGenerator generator = null;
        try {
            generator = KeyPairGenerator.getInstance("RSA");
            generator.initialize(2048, new SecureRandom());
            KeyPair keyPair = generator.generateKeyPair();

            SubjectPublicKeyInfo subjectPublicKeyInfo = SubjectPublicKeyInfo.getInstance(
                keyPair.getPublic().getEncoded()
            );

            X509v3CertificateBuilder certificateBuilder = new X509v3CertificateBuilder(
                nameBuilder.build(),
                serial,
                startDate,
                expiryDate,
                Locale.ENGLISH,
                nameBuilder.build(),
                subjectPublicKeyInfo
            );

            GeneralName[] gnArray = new GeneralName[]{new GeneralName(GeneralName.dNSName, InetAddress.getLocalHost().getHostName()), new GeneralName(GeneralName.uniformResourceIdentifier, APPURI)};


            GeneralNames subjectAltNames = GeneralNames.getInstance(new DERSequence(gnArray));
            certificateBuilder.addExtension(Extension.subjectAlternativeName, false, subjectAltNames);

            ContentSigner sigGen = new JcaContentSignerBuilder("SHA1withRSA").setProvider("BC").build(keyPair.getPrivate());

            X509CertificateHolder certificateHolder = certificateBuilder.build(sigGen);

            JcaX509CertificateConverter certificateConvertor = new JcaX509CertificateConverter();
            certificateConvertor.setProvider(new BouncyCastleProvider());

            CertificateKeyPair ckp = new CertificateKeyPair(keyPair, certificateConvertor.getCertificate(certificateHolder));

            return ckp;

        } catch (Exception e) {
            LOGGER.error("Security Algorithim is unsupported for certificate");
            return null;
        }
    }