package com.cloudhopper.smpp.ssl;
/*
* #%L
* ch-smpp
* %%
* Copyright (C) 2009 - 2013 Cloudhopper by Twitter
* %%
* Licensed 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.
* #L%
*/
import java.security.GeneralSecurityException;
import java.security.InvalidParameterException;
import java.security.KeyStore;
import java.security.KeyStoreException;
import java.security.Security;
import java.security.cert.CRL;
import java.security.cert.CertPathBuilder;
import java.security.cert.CertPathBuilderResult;
import java.security.cert.CertPathValidator;
import java.security.cert.CertStore;
import java.security.cert.Certificate;
import java.security.cert.CertificateException;
import java.security.cert.CollectionCertStoreParameters;
import java.security.cert.PKIXBuilderParameters;
import java.security.cert.X509CertSelector;
import java.security.cert.X509Certificate;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Enumeration;
import java.util.concurrent.atomic.AtomicLong;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Convenience class to handle validation of certificates, aliases and keystores
*
* Allows specifying Certificate Revocation List (CRL), as well as enabling
* CRL Distribution Points Protocol (CRLDP) certificate extension support,
* and also enabling On-Line Certificate Status Protocol (OCSP) support.
*
* IMPORTANT: at least one of the above mechanisms *MUST* be configured and
* operational, otherwise certificate validation *WILL FAIL* unconditionally.
*
* @author Jetty7
*/
public class CertificateValidator
{
private static final Logger logger = LoggerFactory.getLogger(CertificateValidator.class);
private static AtomicLong aliasCount = new AtomicLong();
private KeyStore trustStore;
private Collection<? extends CRL> crls;
/** Maximum certification path length (n - number of intermediate certs, -1 for unlimited) */
private int maxCertPathLength = -1;
/** CRL Distribution Points (CRLDP) support */
private boolean enableCRLDP = false;
/** On-Line Certificate Status Protocol (OCSP) support */
private boolean enableOCSP = false;
/** Location of OCSP Responder */
private String ocspResponderURL;
/**
* creates an instance of the certificate validator
*
* @param trustStore
* @param crls
*/
public CertificateValidator(KeyStore trustStore, Collection<? extends CRL> crls) {
if (trustStore == null) {
throw new InvalidParameterException("TrustStore must be specified for CertificateValidator.");
}
this.trustStore = trustStore;
this.crls = crls;
}
/**
* validates all aliases inside of a given keystore
*
* @param keyStore
* @throws CertificateException
*/
public void validate(KeyStore keyStore) throws CertificateException {
try {
Enumeration<String> aliases = keyStore.aliases();
for ( ; aliases.hasMoreElements(); ) {
String alias = aliases.nextElement();
validate(keyStore,alias);
}
} catch (KeyStoreException kse) {
throw new CertificateException("Unable to retrieve aliases from keystore", kse);
}
}
/**
* validates a specific alias inside of the keystore being passed in
*
* @param keyStore
* @param keyAlias
* @return the keyAlias if valid
* @throws CertificateException
*/
public String validate(KeyStore keyStore, String keyAlias) throws CertificateException {
String result = null;
if (keyAlias != null) {
try {
validate(keyStore, keyStore.getCertificate(keyAlias));
} catch (KeyStoreException kse) {
logger.debug("", kse);
throw new CertificateException("Unable to validate certificate" +
" for alias [" + keyAlias + "]: " + kse.getMessage(), kse);
}
result = keyAlias;
}
return result;
}
/**
* validates a specific certificate inside of the keystore being passed in
*
* @param keyStore
* @param cert
* @throws CertificateException
*/
public void validate(KeyStore keyStore, Certificate cert) throws CertificateException {
Certificate[] certChain = null;
if (cert != null && cert instanceof X509Certificate) {
((X509Certificate)cert).checkValidity();
String certAlias = null;
try {
if (keyStore == null) {
throw new InvalidParameterException("Keystore cannot be null");
}
certAlias = keyStore.getCertificateAlias((X509Certificate)cert);
if (certAlias == null) {
certAlias = "CHSMPP" + String.format("%016X", aliasCount.incrementAndGet());
keyStore.setCertificateEntry(certAlias, cert);
}
certChain = keyStore.getCertificateChain(certAlias);
if (certChain == null || certChain.length == 0) {
throw new IllegalStateException("Unable to retrieve certificate chain");
}
}
catch (KeyStoreException kse) {
logger.debug("", kse);
throw new CertificateException("Unable to validate certificate" +
(certAlias == null ? "":" for alias [" +certAlias + "]") + ": " + kse.getMessage(), kse);
}
validate(certChain);
}
}
public void validate(Certificate[] certChain) throws CertificateException {
try {
ArrayList<X509Certificate> certList = new ArrayList<X509Certificate>();
for (Certificate item : certChain) {
if (item == null) continue;
if (!(item instanceof X509Certificate)) {
throw new IllegalStateException("Invalid certificate type in chain");
}
certList.add((X509Certificate)item);
}
if (certList.isEmpty()) {
throw new IllegalStateException("Invalid certificate chain");
}
X509CertSelector certSelect = new X509CertSelector();
certSelect.setCertificate(certList.get(0));
// Configure certification path builder parameters
PKIXBuilderParameters pbParams = new PKIXBuilderParameters(trustStore, certSelect);
pbParams.addCertStore(CertStore.getInstance("Collection", new CollectionCertStoreParameters(certList)));
// Set maximum certification path length
pbParams.setMaxPathLength(maxCertPathLength);
// Enable revocation checking
pbParams.setRevocationEnabled(true);
// Set static Certificate Revocation List
if (crls != null && !crls.isEmpty()) {
pbParams.addCertStore(CertStore.getInstance("Collection", new CollectionCertStoreParameters(crls)));
}
// Enable On-Line Certificate Status Protocol (OCSP) support
if (enableOCSP) {
Security.setProperty("ocsp.enable","true");
}
// Enable Certificate Revocation List Distribution Points (CRLDP) support
if (enableCRLDP) {
System.setProperty("com.sun.security.enableCRLDP","true");
}
// Build certification path
CertPathBuilderResult buildResult = CertPathBuilder.getInstance("PKIX").build(pbParams);
// Validate certification path
CertPathValidator.getInstance("PKIX").validate(buildResult.getCertPath(),pbParams);
} catch (GeneralSecurityException gse) {
logger.debug("", gse);
throw new CertificateException("Unable to validate certificate: " + gse.getMessage(), gse);
}
}
public KeyStore getTrustStore() {
return trustStore;
}
public Collection<? extends CRL> getCrls() {
return crls;
}
/**
* @return Maximum number of intermediate certificates in
* the certification path (-1 for unlimited)
*/
public int getMaxCertPathLength() {
return maxCertPathLength;
}
/**
* @param maxCertPathLength maximum number of intermediate certificates in
* the certification path (-1 for unlimited)
*/
public void setMaxCertPathLength(int maxCertPathLength) {
maxCertPathLength = maxCertPathLength;
}
/**
* @return true if CRL Distribution Points support is enabled
*/
public boolean isEnableCRLDP() {
return enableCRLDP;
}
/**
* Enables CRL Distribution Points Support
* @param enableCRLDP true - turn on, false - turns off
*/
public void setEnableCRLDP(boolean enableCRLDP) {
enableCRLDP = enableCRLDP;
}
/**
* @return true if On-Line Certificate Status Protocol support is enabled
*/
public boolean isEnableOCSP() {
return enableOCSP;
}
/**
* Enables On-Line Certificate Status Protocol support
* @param enableOCSP true - turn on, false - turn off
*/
public void setEnableOCSP(boolean enableOCSP) {
enableOCSP = enableOCSP;
}
/**
* @return Location of the OCSP Responder
*/
public String getOcspResponderURL() {
return ocspResponderURL;
}
/**
* Set the location of the OCSP Responder.
* @param ocspResponderURL location of the OCSP Responder
*/
public void setOcspResponderURL(String ocspResponderURL) {
ocspResponderURL = ocspResponderURL;
}
}