Skip to content

Instantly share code, notes, and snippets.

@Maurice-Betzel
Created December 1, 2022 19:15
Show Gist options
  • Save Maurice-Betzel/40ae823c72951e8b5e55ff801dc43f9b to your computer and use it in GitHub Desktop.
Save Maurice-Betzel/40ae823c72951e8b5e55ff801dc43f9b to your computer and use it in GitHub Desktop.
Programmatic keyfile creation and PEM file import
/**
* Create a KeyStore from standard PEM file
*
* @param privateKeyPem the private key PEM file
* @param certificatePem the certificate(s) PEM file
* @param the password to set to protect the private key
*/
public static KeyStore createKeyStore(File privateKeyPem, File certificatePem, final String password)
throws Exception, KeyStoreException, IOException, NoSuchAlgorithmException, CertificateException {
final X509Certificate[] cert = createCertificates(certificatePem);
final KeyStore keystore = KeyStore.getInstance("JKS");
keystore.load(null);
// Import private key
final PrivateKey key = createPrivateKey(privateKeyPem);
keystore.setKeyEntry(privateKeyPem.getName(), key, password.toCharArray(), cert);
return keystore;
}
public static SSLServerSocketFactory createSSLFactory(File privateKeyPem, File certificatePem, String password) throws Exception {
final SSLContext context = SSLContext.getInstance("TLS");
final KeyStore keystore = createKeyStore(privateKeyPem, certificatePem, password);
final KeyManagerFactory kmf = KeyManagerFactory.getInstance("SunX509");
kmf.init(keystore, password.toCharArray());
final KeyManager[] km = kmf.getKeyManagers();
context.init(km, null, null);
return context.getServerSocketFactory();
}
private static PrivateKey createPrivateKey(File privateKeyPem) throws Exception {
final BufferedReader r = new BufferedReader(new FileReader(privateKeyPem));
String s = r.readLine();
if (s == null || !s.contains("BEGIN PRIVATE KEY")) {
r.close();
throw new IllegalArgumentException("No PRIVATE KEY found");
}
final StringBuffer b = new StringBuffer();
s = "";
while (s != null) {
if (s.contains("END PRIVATE KEY")) {
break;
}
b.append(s);
s = r.readLine();
}
r.close();
final String hexString = b.toString();
final byte[] bytes = DatatypeConverter.parseBase64Binary(hexString);
return generatePrivateKeyFromDER(bytes);
}
private static X509Certificate[] createCertificates(File certificatePem) throws Exception {
final List<X509Certificate> result = new ArrayList<X509Certificate>();
final BufferedReader r = new BufferedReader(new FileReader(certificatePem));
String s = r.readLine();
if (s == null || !s.contains("BEGIN CERTIFICATE")) {
r.close();
throw new IllegalArgumentException("No CERTIFICATE found");
}
StringBuffer b = new StringBuffer();
while (s != null) {
if (s.contains("END CERTIFICATE")) {
String hexString = b.toString();
final byte[] bytes = DatatypeConverter.parseBase64Binary(hexString);
X509Certificate cert = generateCertificateFromDER(bytes);
result.add(cert);
b = new StringBuffer();
} else {
if (!s.startsWith("----")) {
b.append(s);
}
}
s = r.readLine();
}
r.close();
return result.toArray(new X509Certificate[result.size()]);
}
private static RSAPrivateKey generatePrivateKeyFromDER(byte[] keyBytes) throws InvalidKeySpecException, NoSuchAlgorithmException {
final PKCS8EncodedKeySpec spec = new PKCS8EncodedKeySpec(keyBytes);
final KeyFactory factory = KeyFactory.getInstance("RSA");
return (RSAPrivateKey) factory.generatePrivate(spec);
}
private static X509Certificate generateCertificateFromDER(byte[] certBytes) throws CertificateException {
final CertificateFactory factory = CertificateFactory.getInstance("X.509");
return (X509Certificate) factory.generateCertificate(new ByteArrayInputStream(certBytes));
}
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment