/*
* Copyright 2014 The Netty Project
*
* The Netty Project licenses this file to you under the Apache License,
* version 2.0 (the "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*/
package io.netty.handler.ssl.util;
import io.netty.buffer.Unpooled;
import io.netty.handler.codec.base64.Base64;
import io.netty.util.CharsetUtil;
import io.netty.util.internal.logging.InternalLogger;
import io.netty.util.internal.logging.InternalLoggerFactory;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.NoSuchAlgorithmException;
import java.security.PrivateKey;
import java.security.SecureRandom;
import java.security.cert.CertificateEncodingException;
import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;
import java.util.Date;
/**
* Generates a temporary self-signed certificate for testing purposes.
* <p>
* <strong>NOTE:</strong>
* Never use the certificate and private key generated by this class in production.
* It is purely for testing purposes, and thus it is very insecure.
* It even uses an insecure pseudo-random generator for faster generation internally.
* </p><p>
* A X.509 certificate file and a RSA private key file are generated in a system's temporary directory using
* {@link java.io.File#createTempFile(String, String)}, and they are deleted when the JVM exits using
* {@link java.io.File#deleteOnExit()}.
* </p><p>
* At first, this method tries to use OpenJDK's X.509 implementation (the {@code sun.security.x509} package).
* If it fails, it tries to use <a href="http://www.bouncycastle.org/">Bouncy Castle</a> as a fallback.
* </p>
*/
public final class SelfSignedCertificate {
private static final InternalLogger logger = InternalLoggerFactory.getInstance(SelfSignedCertificate.class);
/** Current time minus 1 year, just in case software clock goes back due to time synchronization */
static final Date NOT_BEFORE = new Date(System.currentTimeMillis() - 86400000L * 365);
/** The maximum possible value in X.509 specification: 9999-12-31 23:59:59 */
static final Date NOT_AFTER = new Date(253402300799000L);
private final File certificate;
private final File privateKey;
/**
* Creates a new instance.
*/
public SelfSignedCertificate() throws CertificateException {
this("example.com");
}
/**
* Creates a new instance.
*
* @param fqdn a fully qualified domain name
*/
public SelfSignedCertificate(String fqdn) throws CertificateException {
// Bypass entrophy collection by using insecure random generator.
// We just want to generate it without any delay because it's for testing purposes only.
this(fqdn, ThreadLocalInsecureRandom.current(), 1024);
}
/**
* Creates a new instance.
*
* @param fqdn a fully qualified domain name
* @param random the {@link java.security.SecureRandom} to use
* @param bits the number of bits of the generated private key
*/
public SelfSignedCertificate(String fqdn, SecureRandom random, int bits) throws CertificateException {
// Generate an RSA key pair.
final KeyPair keypair;
try {
KeyPairGenerator keyGen = KeyPairGenerator.getInstance("RSA");
keyGen.initialize(bits, random);
keypair = keyGen.generateKeyPair();
} catch (NoSuchAlgorithmException e) {
// Should not reach here because every Java implementation must have RSA key pair generator.
throw new Error(e);
}
String[] paths;
try {
// Try the OpenJDK's proprietary implementation.
paths = OpenJdkSelfSignedCertGenerator.generate(fqdn, keypair, random);
} catch (Throwable t) {
logger.debug("Failed to generate a self-signed X.509 certificate using sun.security.x509:", t);
try {
// Try Bouncy Castle if the current JVM didn't have sun.security.x509.
paths = BouncyCastleSelfSignedCertGenerator.generate(fqdn, keypair, random);
} catch (Throwable t2) {
logger.debug("Failed to generate a self-signed X.509 certificate using Bouncy Castle:", t2);
throw new CertificateException(
"No provider succeeded to generate a self-signed certificate. " +
"See debug log for the root cause.");
}
}
certificate = new File(paths[0]);
privateKey = new File(paths[1]);
}
/**
* Returns the generated X.509 certificate file in PEM format.
*/
public File certificate() {
return certificate;
}
/**
* Returns the generated RSA private key file in PEM format.
*/
public File privateKey() {
return privateKey;
}
/**
* Deletes the generated X.509 certificate file and RSA private key file.
*/
public void delete() {
safeDelete(certificate);
safeDelete(privateKey);
}
static String[] newSelfSignedCertificate(
String fqdn, PrivateKey key, X509Certificate cert) throws IOException, CertificateEncodingException {
// Encode the private key into a file.
String keyText = "-----BEGIN PRIVATE KEY-----\n" +
Base64.encode(Unpooled.wrappedBuffer(key.getEncoded()), true).toString(CharsetUtil.US_ASCII) +
"\n-----END PRIVATE KEY-----\n";
File keyFile = File.createTempFile("keyutil_" + fqdn + '_', ".key");
keyFile.deleteOnExit();
OutputStream keyOut = new FileOutputStream(keyFile);
try {
keyOut.write(keyText.getBytes(CharsetUtil.US_ASCII));
keyOut.close();
keyOut = null;
} finally {
if (keyOut != null) {
safeClose(keyFile, keyOut);
safeDelete(keyFile);
}
}
// Encode the certificate into a CRT file.
String certText = "-----BEGIN CERTIFICATE-----\n" +
Base64.encode(Unpooled.wrappedBuffer(cert.getEncoded()), true).toString(CharsetUtil.US_ASCII) +
"\n-----END CERTIFICATE-----\n";
File certFile = File.createTempFile("keyutil_" + fqdn + '_', ".crt");
certFile.deleteOnExit();
OutputStream certOut = new FileOutputStream(certFile);
try {
certOut.write(certText.getBytes(CharsetUtil.US_ASCII));
certOut.close();
certOut = null;
} finally {
if (certOut != null) {
safeClose(certFile, certOut);
safeDelete(certFile);
safeDelete(keyFile);
}
}
return new String[] { certFile.getPath(), keyFile.getPath() };
}
private static void safeDelete(File certFile) {
if (!certFile.delete()) {
logger.warn("Failed to delete a file: " + certFile);
}
}
private static void safeClose(File keyFile, OutputStream keyOut) {
try {
keyOut.close();
} catch (IOException e) {
logger.warn("Failed to close a file: " + keyFile, e);
}
}
}