Github user ivmaykov commented on a diff in the pull request:
https://github.com/apache/zookeeper/pull/184#discussion_r194233492
--- Diff: src/java/main/org/apache/zookeeper/common/ZKTrustManager.java ---
@@ -0,0 +1,144 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF 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 org.apache.zookeeper.common;
+
+import org.apache.http.conn.ssl.DefaultHostnameVerifier;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import javax.net.ssl.SSLEngine;
+import javax.net.ssl.SSLException;
+import javax.net.ssl.X509ExtendedTrustManager;
+import java.net.InetAddress;
+import java.net.Socket;
+import java.net.UnknownHostException;
+import java.security.cert.CertificateException;
+import java.security.cert.X509Certificate;
+
+/**
+ * A custom TrustManager that supports hostname verification via
org.apache.http.conn.ssl.DefaultHostnameVerifier.
+ *
+ * We attempt to perform verification using just the IP address first and
if that fails will attempt to perform a
+ * reverse DNS lookup and verify using the hostname.
+ */
+public class ZKTrustManager extends X509ExtendedTrustManager {
+
+ private static final Logger LOG =
LoggerFactory.getLogger(ZKTrustManager.class);
+
+ private X509ExtendedTrustManager x509ExtendedTrustManager;
+ private boolean hostnameVerificationEnabled;
+ private boolean shouldVerifyClientHostname;
+
+ private DefaultHostnameVerifier hostnameVerifier;
+
+ /**
+ * Instantiate a new ZKTrustManager.
+ *
+ * @param x509ExtendedTrustManager The trustmanager to use for
checkClientTrusted/checkServerTrusted logic
+ * @param verifySSLServerHostname If true, this TrustManager should
verify hostnames of servers that this
+ * instance connects to.
+ * @param verifySSLClientHostname If true, and
verifySSLServerHostname is true, the hostname of a client
+ * connecting to this machine will be
verified in addition to the servers that this
+ * instance connects to. If false, and
verifySSLServerHostname is true, only
+ * the hostnames of servers that this
instance connects to will be verified. If
+ * verifySSLServerHostname is false,
this argument is ignored.
+ */
+ public ZKTrustManager(X509ExtendedTrustManager
x509ExtendedTrustManager, boolean verifySSLServerHostname,
+ boolean verifySSLClientHostname) {
+ this.x509ExtendedTrustManager = x509ExtendedTrustManager;
+ this.hostnameVerificationEnabled = verifySSLServerHostname;
+ this.shouldVerifyClientHostname = verifySSLClientHostname;
+
+ hostnameVerifier = new DefaultHostnameVerifier();
+ }
+
+ @Override
+ public X509Certificate[] getAcceptedIssuers() {
+ return x509ExtendedTrustManager.getAcceptedIssuers();
+ }
+
+ @Override
+ public void checkClientTrusted(X509Certificate[] chain, String
authType, Socket socket) throws CertificateException {
+ if (hostnameVerificationEnabled && shouldVerifyClientHostname) {
--- End diff --
might be simpler to just have separate booleans for verifying server
hostname and verifying client hostname. That way one or the other or both can
be enabled. Right now, it looks like to enable client hostname verification,
server hostname verification must be enabled as well. What do you think?
---
