io.netty.handler.ssl.util.SelfSignedCertificate Maven / Gradle / Ivy
/*
* 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.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.handler.codec.base64.Base64;
import io.netty.util.CharsetUtil;
import io.netty.util.internal.SystemPropertyUtil;
import io.netty.util.internal.ThrowableUtil;
import io.netty.util.internal.logging.InternalLogger;
import io.netty.util.internal.logging.InternalLoggerFactory;
import java.io.File;
import java.io.FileInputStream;
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.CertificateFactory;
import java.security.cert.X509Certificate;
import java.util.Date;
/**
* Generates a temporary self-signed certificate for testing purposes.
*
* NOTE:
* 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.
*
* An 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()}.
*
* 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 Bouncy Castle as a fallback.
*
*/
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 */
private static final Date DEFAULT_NOT_BEFORE = new Date(SystemPropertyUtil.getLong(
"io.netty.selfSignedCertificate.defaultNotBefore", System.currentTimeMillis() - 86400000L * 365));
/** The maximum possible value in X.509 specification: 9999-12-31 23:59:59 */
private static final Date DEFAULT_NOT_AFTER = new Date(SystemPropertyUtil.getLong(
"io.netty.selfSignedCertificate.defaultNotAfter", 253402300799000L));
/**
* FIPS 140-2 encryption requires the key length to be 2048 bits or greater.
* Let's use that as a sane default but allow the default to be set dynamically
* for those that need more stringent security requirements.
*/
private static final int DEFAULT_KEY_LENGTH_BITS =
SystemPropertyUtil.getInt("io.netty.handler.ssl.util.selfSignedKeyStrength", 2048);
private final File certificate;
private final File privateKey;
private final X509Certificate cert;
private final PrivateKey key;
/**
* Creates a new instance.
*/
public SelfSignedCertificate() throws CertificateException {
this(DEFAULT_NOT_BEFORE, DEFAULT_NOT_AFTER);
}
/**
* Creates a new instance.
* @param notBefore Certificate is not valid before this time
* @param notAfter Certificate is not valid after this time
*/
public SelfSignedCertificate(Date notBefore, Date notAfter) throws CertificateException {
this("example.com", notBefore, notAfter);
}
/**
* Creates a new instance.
*
* @param fqdn a fully qualified domain name
*/
public SelfSignedCertificate(String fqdn) throws CertificateException {
this(fqdn, DEFAULT_NOT_BEFORE, DEFAULT_NOT_AFTER);
}
/**
* Creates a new instance.
*
* @param fqdn a fully qualified domain name
* @param notBefore Certificate is not valid before this time
* @param notAfter Certificate is not valid after this time
*/
public SelfSignedCertificate(String fqdn, Date notBefore, Date notAfter) throws CertificateException {
// Bypass entropy 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(), DEFAULT_KEY_LENGTH_BITS, notBefore, notAfter);
}
/**
* 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 {
this(fqdn, random, bits, DEFAULT_NOT_BEFORE, DEFAULT_NOT_AFTER);
}
/**
* 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
* @param notBefore Certificate is not valid before this time
* @param notAfter Certificate is not valid after this time
*/
public SelfSignedCertificate(String fqdn, SecureRandom random, int bits, Date notBefore, Date notAfter)
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, notBefore, notAfter);
} 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, notBefore, notAfter);
} catch (Throwable t2) {
logger.debug("Failed to generate a self-signed X.509 certificate using Bouncy Castle:", t2);
final CertificateException certificateException = new CertificateException(
"No provider succeeded to generate a self-signed certificate. " +
"See debug log for the root cause.", t2);
ThrowableUtil.addSuppressed(certificateException, t);
throw certificateException;
}
}
certificate = new File(paths[0]);
privateKey = new File(paths[1]);
key = keypair.getPrivate();
FileInputStream certificateInput = null;
try {
certificateInput = new FileInputStream(certificate);
cert = (X509Certificate) CertificateFactory.getInstance("X509").generateCertificate(certificateInput);
} catch (Exception e) {
throw new CertificateEncodingException(e);
} finally {
if (certificateInput != null) {
try {
certificateInput.close();
} catch (IOException e) {
if (logger.isWarnEnabled()) {
logger.warn("Failed to close a file: " + certificate, e);
}
}
}
}
}
/**
* 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;
}
/**
* Returns the generated X.509 certificate.
*/
public X509Certificate cert() {
return cert;
}
/**
* Returns the generated RSA private key.
*/
public PrivateKey key() {
return key;
}
/**
* 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.
ByteBuf wrappedBuf = Unpooled.wrappedBuffer(key.getEncoded());
ByteBuf encodedBuf;
final String keyText;
try {
encodedBuf = Base64.encode(wrappedBuf, true);
try {
keyText = "-----BEGIN PRIVATE KEY-----\n" +
encodedBuf.toString(CharsetUtil.US_ASCII) +
"\n-----END PRIVATE KEY-----\n";
} finally {
encodedBuf.release();
}
} finally {
wrappedBuf.release();
}
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);
}
}
wrappedBuf = Unpooled.wrappedBuffer(cert.getEncoded());
final String certText;
try {
encodedBuf = Base64.encode(wrappedBuf, true);
try {
// Encode the certificate into a CRT file.
certText = "-----BEGIN CERTIFICATE-----\n" +
encodedBuf.toString(CharsetUtil.US_ASCII) +
"\n-----END CERTIFICATE-----\n";
} finally {
encodedBuf.release();
}
} finally {
wrappedBuf.release();
}
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()) {
if (logger.isWarnEnabled()) {
logger.warn("Failed to delete a file: " + certFile);
}
}
}
private static void safeClose(File keyFile, OutputStream keyOut) {
try {
keyOut.close();
} catch (IOException e) {
if (logger.isWarnEnabled()) {
logger.warn("Failed to close a file: " + keyFile, e);
}
}
}
}