axis-rt-core/src/main/java/org/apache/axis/components/net/JSSESocketFactory.java - axis-axis1-java - Git at Google

 /*
  * Copyright 2001-2004 The Apache Software Foundation.
  *
  * 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.
  */
 package org.apache.axis.components.net;

 import java.io.BufferedWriter;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
 import java.io.OutputStreamWriter;
 import java.io.PrintWriter;
 import java.net.Socket;
 import java.security.cert.Certificate;
 import java.security.cert.CertificateParsingException;
 import java.security.cert.X509Certificate;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Hashtable;
 import java.util.Iterator;
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Locale;
 import java.util.regex.Pattern;

 import javax.naming.InvalidNameException;
 import javax.naming.NamingException;
 import javax.naming.directory.Attribute;
 import javax.naming.directory.Attributes;
 import javax.naming.ldap.LdapName;
 import javax.naming.ldap.Rdn;
 import javax.net.ssl.SSLException;
 import javax.net.ssl.SSLSession;
 import javax.net.ssl.SSLSocket;
 import javax.net.ssl.SSLSocketFactory;

 import org.apache.axis.utils.Messages;
 import org.apache.axis.utils.StringUtils;
 import org.apache.axis.utils.XMLUtils;


 /**
  * SSL socket factory. It _requires_ a valid RSA key and
  * JSSE. (borrowed code from tomcat)
  *
  * THIS CODE STILL HAS DEPENDENCIES ON sun.* and com.sun.*
  *
  * @author Davanum Srinivas (dims@yahoo.com)
  */
 public class JSSESocketFactory extends DefaultSocketFactory implements SecureSocketFactory {

     // This is a a sorted list, if you insert new elements do it orderdered.
     private final static String[] BAD_COUNTRY_2LDS =
         {"ac", "co", "com", "ed", "edu", "go", "gouv", "gov", "info",
             "lg", "ne", "net", "or", "org"};
     /** Field sslFactory           */
     protected SSLSocketFactory sslFactory = null;

     /**
      * Constructor JSSESocketFactory
      *
      * @param attributes
      */
     public JSSESocketFactory(Hashtable attributes) {
         super(attributes);
     }

     /**
      * Initialize the SSLSocketFactory
      * @throws IOException
      */
     protected void initFactory() throws IOException {
         sslFactory = (SSLSocketFactory)SSLSocketFactory.getDefault();
     }

     /**
      * creates a secure socket
      *
      * @param host
      * @param port
      * @param otherHeaders
      * @param useFullURL
      *
      * @return Socket
      * @throws Exception
      */
     public Socket create(
             String host, int port, StringBuffer otherHeaders, BooleanHolder useFullURL)
             throws Exception {
         if (sslFactory == null) {
             initFactory();
         }
         if (port == -1) {
             port = 443;
         }

         TransportClientProperties tcp = TransportClientPropertiesFactory.create("https");

         boolean hostInNonProxyList = isHostInNonProxyList(host, tcp.getNonProxyHosts());

         Socket sslSocket = null;
         if (tcp.getProxyHost().length() == 0 || hostInNonProxyList) {
             // direct SSL connection
             sslSocket = sslFactory.createSocket(host, port);
         } else {

             // Default proxy port is 80, even for https
             int tunnelPort = (tcp.getProxyPort().length() != 0)
                              ? Integer.parseInt(tcp.getProxyPort())
                              : 80;
             if (tunnelPort < 0)
                 tunnelPort = 80;

             // Create the regular socket connection to the proxy
             Socket tunnel = new Socket(tcp.getProxyHost(), tunnelPort);

             // The tunnel handshake method (condensed and made reflexive)
             OutputStream tunnelOutputStream = tunnel.getOutputStream();
             PrintWriter out = new PrintWriter(
                     new BufferedWriter(new OutputStreamWriter(tunnelOutputStream)));

             // More secure version... engage later?
             // PasswordAuthentication pa =
             // Authenticator.requestPasswordAuthentication(
             // InetAddress.getByName(tunnelHost),
             // tunnelPort, "SOCK", "Proxy","HTTP");
             // if(pa == null){
             // printDebug("No Authenticator set.");
             // }else{
             // printDebug("Using Authenticator.");
             // tunnelUser = pa.getUserName();
             // tunnelPassword = new String(pa.getPassword());
             // }
             out.print("CONNECT " + host + ":" + port + " HTTP/1.0\r\n"
                     + "User-Agent: AxisClient");
             if (tcp.getProxyUser().length() != 0 &&
                 tcp.getProxyPassword().length() != 0) {

                 // add basic authentication header for the proxy
                 String encodedPassword = XMLUtils.base64encode((tcp.getProxyUser()
                         + ":"
                         + tcp.getProxyPassword()).getBytes());

                 out.print("\nProxy-Authorization: Basic " + encodedPassword);
             }
             out.print("\nContent-Length: 0");
             out.print("\nPragma: no-cache");
             out.print("\r\n\r\n");
             out.flush();
             InputStream tunnelInputStream = tunnel.getInputStream();

             if (log.isDebugEnabled()) {
                 log.debug(Messages.getMessage("isNull00", "tunnelInputStream",
                         "" + (tunnelInputStream
                         == null)));
             }
             String replyStr = "";

             // Make sure to read all the response from the proxy to prevent SSL negotiation failure
             // Response message terminated by two sequential newlines
             int newlinesSeen = 0;
             boolean headerDone = false;    /* Done on first newline */

             while (newlinesSeen < 2) {
                 int i = tunnelInputStream.read();

                 if (i < 0) {
                     throw new IOException("Unexpected EOF from proxy");
                 }
                 if (i == '\n') {
                     headerDone = true;
                     ++newlinesSeen;
                 } else if (i != '\r') {
                     newlinesSeen = 0;
                     if (!headerDone) {
                         replyStr += String.valueOf((char) i);
                     }
                 }
             }
             if (StringUtils.startsWithIgnoreWhitespaces("HTTP/1.0 200", replyStr) &&
                     StringUtils.startsWithIgnoreWhitespaces("HTTP/1.1 200", replyStr)) {
                 throw new IOException(Messages.getMessage("cantTunnel00",
                         new String[]{
                             tcp.getProxyHost(),
                             "" + tunnelPort,
                             replyStr}));
             }

             // End of condensed reflective tunnel handshake method
             sslSocket = sslFactory.createSocket(tunnel, host, port, true);
             if (log.isDebugEnabled()) {
                 log.debug(Messages.getMessage("setupTunnel00",
                           tcp.getProxyHost(),
                         "" + tunnelPort));
             }
         }

         ((SSLSocket) sslSocket).startHandshake();
         if (log.isDebugEnabled()) {
             log.debug(Messages.getMessage("createdSSL00"));
         }
         verifyHostName(host, (SSLSocket) sslSocket);
         return sslSocket;
     }
     /**
      * Verifies that the given hostname in certicifate is the hostname we are trying to connect to.
      * This resolves CVE-2012-5784 and CVE-2014-3596
      * @param host
      * @param ssl
      * @throws IOException
      */

 	private static void verifyHostName(String host, SSLSocket ssl)
 			throws IOException {
 		if (host == null) {
 			throw new IllegalArgumentException("host to verify was null");
 		}

 		SSLSession session = ssl.getSession();
 		if (session == null) {
             // In our experience this only happens under IBM 1.4.x when
             // spurious (unrelated) certificates show up in the server's chain.
             // Hopefully this will unearth the real problem:
 			InputStream in = ssl.getInputStream();
 			in.available();
             /*
                  If you're looking at the 2 lines of code above because you're
                  running into a problem, you probably have two options:

                     #1.  Clean up the certificate chain that your server
                          is presenting (e.g. edit "/etc/apache2/server.crt" or
                          wherever it is your server's certificate chain is
                          defined).

                                              OR

                     #2.   Upgrade to an IBM 1.5.x or greater JVM, or switch to a
                           non-IBM JVM.
               */

             // If ssl.getInputStream().available() didn't cause an exception,
             // maybe at least now the session is available?
 			session = ssl.getSession();
 			if (session == null) {
                 // If it's still null, probably a startHandshake() will
                 // unearth the real problem.
 				ssl.startHandshake();

                 // Okay, if we still haven't managed to cause an exception,
                 // might as well go for the NPE.  Or maybe we're okay now?
 				session = ssl.getSession();
 			}
 		}

 		Certificate[] certs = session.getPeerCertificates();
 		verifyHostName(host.trim().toLowerCase(Locale.US),  (X509Certificate) certs[0]);
 	}
 	/**
 	 * Extract the names from the certificate and tests host matches one of them
 	 * @param host
 	 * @param cert
 	 * @throws SSLException
 	 */

 	private static void verifyHostName(final String host, X509Certificate cert)
 			throws SSLException {
         // I'm okay with being case-insensitive when comparing the host we used
         // to establish the socket to the hostname in the certificate.
         // Don't trim the CN, though.

 		String[] cns = getCNs(cert);
 		String[] subjectAlts = getDNSSubjectAlts(cert);
 		verifyHostName(host, cns, subjectAlts);

 	}

 	/**
 	 * Extract all alternative names from a certificate.
 	 * @param cert
 	 * @return
 	 */
 	private static String[] getDNSSubjectAlts(X509Certificate cert) {
 		LinkedList subjectAltList = new LinkedList();
 		Collection c = null;
 		try {
 			c = cert.getSubjectAlternativeNames();
 		} catch (CertificateParsingException cpe) {
 			// Should probably log.debug() this?
 			cpe.printStackTrace();
 		}
 		if (c != null) {
 			Iterator it = c.iterator();
 			while (it.hasNext()) {
 				List list = (List) it.next();
 				int type = ((Integer) list.get(0)).intValue();
 				// If type is 2, then we've got a dNSName
 				if (type == 2) {
 					String s = (String) list.get(1);
 					subjectAltList.add(s);
 				}
 			}
 		}
 		if (!subjectAltList.isEmpty()) {
 			String[] subjectAlts = new String[subjectAltList.size()];
 			subjectAltList.toArray(subjectAlts);
 			return subjectAlts;
 		} else {
 			return new String[0];
 		}

 	}
 	/**
 	 * Verifies
 	 * @param host
 	 * @param cn
 	 * @param subjectAlts
 	 * @throws SSLException
 	 */

 	private static void verifyHostName(final String host, String[] cns, String[] subjectAlts)throws SSLException{
 		StringBuffer cnTested = new StringBuffer();

 		for (int i = 0; i < subjectAlts.length; i++){
 			String name = subjectAlts[i];
 			if (name != null) {
 				name = name.toLowerCase(Locale.US);
 				if (verifyHostName(host, name)){
 					return;
 				}
 				cnTested.append("/").append(name);
 			}
 		}
         for (int i = 0; i < cns.length; i++) {
             String cn = cns[i];
             if (cn != null) {
                 cn = cn.toLowerCase(Locale.US);
                 if (verifyHostName(host, cn)) {
                     return;
                 }
                 cnTested.append("/").append(cn);
             }
         }
 		throw new SSLException("hostname in certificate didn't match: <"
 					+ host + "> != <" + cnTested + ">");
 	}

 	private static boolean verifyHostName(final String host, final String cn){
 		if (doWildCard(cn) && !isIPAddress(host)) {
 			return matchesWildCard(cn, host);
 		}
 		return host.equalsIgnoreCase(cn);
 	}
     private static boolean doWildCard(String cn) {
 		// Contains a wildcard
 		// wildcard in the first block
     	// not an ipaddress (ip addres must explicitily be equal)
     	// not using 2nd level common tld : ex: not for *.co.uk
     	String parts[] = cn.split("\\.");
     	return parts.length >= 3 &&
     			parts[0].endsWith("*") &&
     			acceptableCountryWildcard(cn) &&
     			!isIPAddress(cn);
     }

 	private static final Pattern IPV4_PATTERN =
 			Pattern.compile("^(25[0-5]|2[0-4]\\d|[0-1]?\\d?\\d)(\\.(25[0-5]|2[0-4]\\d|[0-1]?\\d?\\d)){3}$");

 	private static final Pattern IPV6_STD_PATTERN =
 			Pattern.compile("^(?:[0-9a-fA-F]{1,4}:){7}[0-9a-fA-F]{1,4}$");

 	private static final Pattern IPV6_HEX_COMPRESSED_PATTERN =
 			Pattern.compile("^((?:[0-9A-Fa-f]{1,4}(?::[0-9A-Fa-f]{1,4})*)?)::((?:[0-9A-Fa-f]{1,4}(?::[0-9A-Fa-f]{1,4})*)?)$");


 	private static boolean isIPAddress(final String hostname) {
 		return hostname != null
 				&& (
 						IPV4_PATTERN.matcher(hostname).matches()
 						|| IPV6_STD_PATTERN.matcher(hostname).matches()
 						|| IPV6_HEX_COMPRESSED_PATTERN.matcher(hostname).matches()
 		);

 	}

 	private static boolean acceptableCountryWildcard(final String cn) {
 		// The CN better have at least two dots if it wants wildcard action,
 		// but can't be [*.co.uk] or [*.co.jp] or [*.org.uk], etc...
 		// The [*.co.uk] problem is an interesting one. Should we just
 		// hope that CA's would never foolishly allow such a
 		// certificate to happen?

 		String[] parts = cn.split("\\.");
 		// Only checks for 3 levels, with country code of 2 letters.
 		if (parts.length > 3 || parts[parts.length - 1].length() != 2) {
 			return true;
 		}
 		String countryCode = parts[parts.length - 2];
 		return Arrays.binarySearch(BAD_COUNTRY_2LDS, countryCode) < 0;
 	}

 	private static boolean matchesWildCard(final String cn,
 			final String hostName) {
 		String parts[] = cn.split("\\.");
 		boolean match = false;
 		String firstpart = parts[0];
 		if (firstpart.length() > 1) {
 			// server∗
 			// e.g. server
 			String prefix =  firstpart.substring(0, firstpart.length() - 1);
 			// skipwildcard part from cn
 			String suffix = cn.substring(firstpart.length());
 			// skip wildcard part from host
 			String hostSuffix = hostName.substring(prefix.length());
 			match = hostName.startsWith(prefix) && hostSuffix.endsWith(suffix);
 		} else {
 			match = hostName.endsWith(cn.substring(1));
 		}
 		if (match) {
 			// I f we ’ r e i n s t r i c t mode ,
 			// [ ∗.foo.com] is not allowed to match [a.b.foo.com]
 			match = countDots(hostName) == countDots(cn);
 		}
 		return match;
 	}

 	private static int countDots(final String data) {
 		int dots = 0;
 		for (int i = 0; i < data.length(); i++) {
 			if (data.charAt(i) == '.') {
 				dots += 1;
 			}
 		}
 		return dots;
 	}


 	private static String[] getCNs(X509Certificate cert) {
           // Note:  toString() seems to do a better job than getName()
           //
           // For example, getName() gives me this:
           // 1.2.840.113549.1.9.1=#16166a756c6975736461766965734063756362632e636f6d
           //
           // whereas toString() gives me this:
           // EMAILADDRESS=juliusdavies@cucbc.com
 		String subjectPrincipal = cert.getSubjectX500Principal().toString();

 		return getCNs(subjectPrincipal);

 	}
 	private static String[] getCNs(String subjectPrincipal) {
         if (subjectPrincipal == null) {
             return null;
         }
         final List cns = new ArrayList();
         try {
             final LdapName subjectDN = new LdapName(subjectPrincipal);
             final List rdns = subjectDN.getRdns();
             for (int i = rdns.size() - 1; i >= 0; i--) {
                 final Rdn rds = (Rdn) rdns.get(i);
                 final Attributes attributes = rds.toAttributes();
                 final Attribute cn = attributes.get("cn");
                 if (cn != null) {
                     try {
                         final Object value = cn.get();
                         if (value != null) {
                             cns.add(value.toString());
                         }
                     }
                     catch (NamingException ignore) {}
                 }
             }
         }
         catch (InvalidNameException ignore) { }
         return cns.isEmpty() ? null : (String[]) cns.toArray(new String[ cns.size() ]);
 	}

 }
	/*
	* Copyright 2001-2004 The Apache Software Foundation.
	*
	* 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.
	*/
	package org.apache.axis.components.net;

	import java.io.BufferedWriter;
	import java.io.IOException;
	import java.io.InputStream;
	import java.io.OutputStream;
	import java.io.OutputStreamWriter;
	import java.io.PrintWriter;
	import java.net.Socket;
	import java.security.cert.Certificate;
	import java.security.cert.CertificateParsingException;
	import java.security.cert.X509Certificate;
	import java.util.ArrayList;
	import java.util.Arrays;
	import java.util.Collection;
	import java.util.Hashtable;
	import java.util.Iterator;
	import java.util.LinkedList;
	import java.util.List;
	import java.util.Locale;
	import java.util.regex.Pattern;

	import javax.naming.InvalidNameException;
	import javax.naming.NamingException;
	import javax.naming.directory.Attribute;
	import javax.naming.directory.Attributes;
	import javax.naming.ldap.LdapName;
	import javax.naming.ldap.Rdn;
	import javax.net.ssl.SSLException;
	import javax.net.ssl.SSLSession;
	import javax.net.ssl.SSLSocket;
	import javax.net.ssl.SSLSocketFactory;

	import org.apache.axis.utils.Messages;
	import org.apache.axis.utils.StringUtils;
	import org.apache.axis.utils.XMLUtils;


	/**
	* SSL socket factory. It _requires_ a valid RSA key and
	* JSSE. (borrowed code from tomcat)
	*
	* THIS CODE STILL HAS DEPENDENCIES ON sun.* and com.sun.*
	*
	* @author Davanum Srinivas (dims@yahoo.com)
	*/
	public class JSSESocketFactory extends DefaultSocketFactory implements SecureSocketFactory {

	// This is a a sorted list, if you insert new elements do it orderdered.
	private final static String[] BAD_COUNTRY_2LDS =
	{"ac", "co", "com", "ed", "edu", "go", "gouv", "gov", "info",
	"lg", "ne", "net", "or", "org"};
	/** Field sslFactory */
	protected SSLSocketFactory sslFactory = null;

	/**
	* Constructor JSSESocketFactory
	*
	* @param attributes
	*/
	public JSSESocketFactory(Hashtable attributes) {
	super(attributes);
	}

	/**
	* Initialize the SSLSocketFactory
	* @throws IOException
	*/
	protected void initFactory() throws IOException {
	sslFactory = (SSLSocketFactory)SSLSocketFactory.getDefault();
	}

	/**
	* creates a secure socket
	*
	* @param host
	* @param port
	* @param otherHeaders
	* @param useFullURL
	*
	* @return Socket
	* @throws Exception
	*/
	public Socket create(
	String host, int port, StringBuffer otherHeaders, BooleanHolder useFullURL)
	throws Exception {
	if (sslFactory == null) {
	initFactory();
	}
	if (port == -1) {
	port = 443;
	}

	TransportClientProperties tcp = TransportClientPropertiesFactory.create("https");

	boolean hostInNonProxyList = isHostInNonProxyList(host, tcp.getNonProxyHosts());

	Socket sslSocket = null;
	if (tcp.getProxyHost().length() == 0 \|\| hostInNonProxyList) {
	// direct SSL connection
	sslSocket = sslFactory.createSocket(host, port);
	} else {

	// Default proxy port is 80, even for https
	int tunnelPort = (tcp.getProxyPort().length() != 0)
	? Integer.parseInt(tcp.getProxyPort())
	: 80;
	if (tunnelPort < 0)
	tunnelPort = 80;

	// Create the regular socket connection to the proxy
	Socket tunnel = new Socket(tcp.getProxyHost(), tunnelPort);

	// The tunnel handshake method (condensed and made reflexive)
	OutputStream tunnelOutputStream = tunnel.getOutputStream();
	PrintWriter out = new PrintWriter(
	new BufferedWriter(new OutputStreamWriter(tunnelOutputStream)));

	// More secure version... engage later?
	// PasswordAuthentication pa =
	// Authenticator.requestPasswordAuthentication(
	// InetAddress.getByName(tunnelHost),
	// tunnelPort, "SOCK", "Proxy","HTTP");
	// if(pa == null){
	// printDebug("No Authenticator set.");
	// }else{
	// printDebug("Using Authenticator.");
	// tunnelUser = pa.getUserName();
	// tunnelPassword = new String(pa.getPassword());
	// }
	out.print("CONNECT " + host + ":" + port + " HTTP/1.0\r\n"
	+ "User-Agent: AxisClient");
	if (tcp.getProxyUser().length() != 0 &&
	tcp.getProxyPassword().length() != 0) {

	// add basic authentication header for the proxy
	String encodedPassword = XMLUtils.base64encode((tcp.getProxyUser()
	+ ":"
	+ tcp.getProxyPassword()).getBytes());

	out.print("\nProxy-Authorization: Basic " + encodedPassword);
	}
	out.print("\nContent-Length: 0");
	out.print("\nPragma: no-cache");
	out.print("\r\n\r\n");
	out.flush();
	InputStream tunnelInputStream = tunnel.getInputStream();

	if (log.isDebugEnabled()) {
	log.debug(Messages.getMessage("isNull00", "tunnelInputStream",
	"" + (tunnelInputStream
	== null)));
	}
	String replyStr = "";

	// Make sure to read all the response from the proxy to prevent SSL negotiation failure
	// Response message terminated by two sequential newlines
	int newlinesSeen = 0;
	boolean headerDone = false; /* Done on first newline */

	while (newlinesSeen < 2) {
	int i = tunnelInputStream.read();

	if (i < 0) {
	throw new IOException("Unexpected EOF from proxy");
	}
	if (i == '\n') {
	headerDone = true;
	++newlinesSeen;
	} else if (i != '\r') {
	newlinesSeen = 0;
	if (!headerDone) {
	replyStr += String.valueOf((char) i);
	}
	}
	}
	if (StringUtils.startsWithIgnoreWhitespaces("HTTP/1.0 200", replyStr) &&
	StringUtils.startsWithIgnoreWhitespaces("HTTP/1.1 200", replyStr)) {
	throw new IOException(Messages.getMessage("cantTunnel00",
	new String[]{
	tcp.getProxyHost(),
	"" + tunnelPort,
	replyStr}));
	}

	// End of condensed reflective tunnel handshake method
	sslSocket = sslFactory.createSocket(tunnel, host, port, true);
	if (log.isDebugEnabled()) {
	log.debug(Messages.getMessage("setupTunnel00",
	tcp.getProxyHost(),
	"" + tunnelPort));
	}
	}

	((SSLSocket) sslSocket).startHandshake();
	if (log.isDebugEnabled()) {
	log.debug(Messages.getMessage("createdSSL00"));
	}
	verifyHostName(host, (SSLSocket) sslSocket);
	return sslSocket;
	}
	/**
	* Verifies that the given hostname in certicifate is the hostname we are trying to connect to.
	* This resolves CVE-2012-5784 and CVE-2014-3596
	* @param host
	* @param ssl
	* @throws IOException
	*/

	private static void verifyHostName(String host, SSLSocket ssl)
	throws IOException {
	if (host == null) {
	throw new IllegalArgumentException("host to verify was null");
	}

	SSLSession session = ssl.getSession();
	if (session == null) {
	// In our experience this only happens under IBM 1.4.x when
	// spurious (unrelated) certificates show up in the server's chain.
	// Hopefully this will unearth the real problem:
	InputStream in = ssl.getInputStream();
	in.available();
	/*
	If you're looking at the 2 lines of code above because you're
	running into a problem, you probably have two options:

	#1. Clean up the certificate chain that your server
	is presenting (e.g. edit "/etc/apache2/server.crt" or
	wherever it is your server's certificate chain is
	defined).

	OR

	#2. Upgrade to an IBM 1.5.x or greater JVM, or switch to a
	non-IBM JVM.
	*/

	// If ssl.getInputStream().available() didn't cause an exception,
	// maybe at least now the session is available?
	session = ssl.getSession();
	if (session == null) {
	// If it's still null, probably a startHandshake() will
	// unearth the real problem.
	ssl.startHandshake();

	// Okay, if we still haven't managed to cause an exception,
	// might as well go for the NPE. Or maybe we're okay now?
	session = ssl.getSession();
	}
	}

	Certificate[] certs = session.getPeerCertificates();
	verifyHostName(host.trim().toLowerCase(Locale.US), (X509Certificate) certs[0]);
	}
	/**
	* Extract the names from the certificate and tests host matches one of them
	* @param host
	* @param cert
	* @throws SSLException
	*/

	private static void verifyHostName(final String host, X509Certificate cert)
	throws SSLException {
	// I'm okay with being case-insensitive when comparing the host we used
	// to establish the socket to the hostname in the certificate.
	// Don't trim the CN, though.

	String[] cns = getCNs(cert);
	String[] subjectAlts = getDNSSubjectAlts(cert);
	verifyHostName(host, cns, subjectAlts);

	}

	/**
	* Extract all alternative names from a certificate.
	* @param cert
	* @return
	*/
	private static String[] getDNSSubjectAlts(X509Certificate cert) {
	LinkedList subjectAltList = new LinkedList();
	Collection c = null;
	try {
	c = cert.getSubjectAlternativeNames();
	} catch (CertificateParsingException cpe) {
	// Should probably log.debug() this?
	cpe.printStackTrace();
	}
	if (c != null) {
	Iterator it = c.iterator();
	while (it.hasNext()) {
	List list = (List) it.next();
	int type = ((Integer) list.get(0)).intValue();
	// If type is 2, then we've got a dNSName
	if (type == 2) {
	String s = (String) list.get(1);
	subjectAltList.add(s);
	}
	}
	}
	if (!subjectAltList.isEmpty()) {
	String[] subjectAlts = new String[subjectAltList.size()];
	subjectAltList.toArray(subjectAlts);
	return subjectAlts;
	} else {
	return new String[0];
	}

	}
	/**
	* Verifies
	* @param host
	* @param cn
	* @param subjectAlts
	* @throws SSLException
	*/

	private static void verifyHostName(final String host, String[] cns, String[] subjectAlts)throws SSLException{
	StringBuffer cnTested = new StringBuffer();

	for (int i = 0; i < subjectAlts.length; i++){
	String name = subjectAlts[i];
	if (name != null) {
	name = name.toLowerCase(Locale.US);
	if (verifyHostName(host, name)){
	return;
	}
	cnTested.append("/").append(name);
	}
	}
	for (int i = 0; i < cns.length; i++) {
	String cn = cns[i];
	if (cn != null) {
	cn = cn.toLowerCase(Locale.US);
	if (verifyHostName(host, cn)) {
	return;
	}
	cnTested.append("/").append(cn);
	}
	}
	throw new SSLException("hostname in certificate didn't match: <"
	+ host + "> != <" + cnTested + ">");
	}

	private static boolean verifyHostName(final String host, final String cn){
	if (doWildCard(cn) && !isIPAddress(host)) {
	return matchesWildCard(cn, host);
	}
	return host.equalsIgnoreCase(cn);
	}
	private static boolean doWildCard(String cn) {
	// Contains a wildcard
	// wildcard in the first block
	// not an ipaddress (ip addres must explicitily be equal)
	// not using 2nd level common tld : ex: not for *.co.uk
	String parts[] = cn.split("\\.");
	return parts.length >= 3 &&
	parts[0].endsWith("*") &&
	acceptableCountryWildcard(cn) &&
	!isIPAddress(cn);
	}

	private static final Pattern IPV4_PATTERN =
	Pattern.compile("^(25[0-5]\|2[0-4]\\d\|[0-1]?\\d?\\d)(\\.(25[0-5]\|2[0-4]\\d\|[0-1]?\\d?\\d)){3}$");

	private static final Pattern IPV6_STD_PATTERN =
	Pattern.compile("^(?:[0-9a-fA-F]{1,4}:){7}[0-9a-fA-F]{1,4}$");

	private static final Pattern IPV6_HEX_COMPRESSED_PATTERN =
	Pattern.compile("^((?:[0-9A-Fa-f]{1,4}(?::[0-9A-Fa-f]{1,4}))?)::((?:[0-9A-Fa-f]{1,4}(?::[0-9A-Fa-f]{1,4}))?)$");


	private static boolean isIPAddress(final String hostname) {
	return hostname != null
	&& (
	IPV4_PATTERN.matcher(hostname).matches()
	\|\| IPV6_STD_PATTERN.matcher(hostname).matches()
	\|\| IPV6_HEX_COMPRESSED_PATTERN.matcher(hostname).matches()
	);

	}

	private static boolean acceptableCountryWildcard(final String cn) {
	// The CN better have at least two dots if it wants wildcard action,
	// but can't be [.co.uk] or [.co.jp] or [*.org.uk], etc...
	// The [*.co.uk] problem is an interesting one. Should we just
	// hope that CA's would never foolishly allow such a
	// certificate to happen?

	String[] parts = cn.split("\\.");
	// Only checks for 3 levels, with country code of 2 letters.
	if (parts.length > 3 \|\| parts[parts.length - 1].length() != 2) {
	return true;
	}
	String countryCode = parts[parts.length - 2];
	return Arrays.binarySearch(BAD_COUNTRY_2LDS, countryCode) < 0;
	}

	private static boolean matchesWildCard(final String cn,
	final String hostName) {
	String parts[] = cn.split("\\.");
	boolean match = false;
	String firstpart = parts[0];
	if (firstpart.length() > 1) {
	// server∗
	// e.g. server
	String prefix = firstpart.substring(0, firstpart.length() - 1);
	// skipwildcard part from cn
	String suffix = cn.substring(firstpart.length());
	// skip wildcard part from host
	String hostSuffix = hostName.substring(prefix.length());
	match = hostName.startsWith(prefix) && hostSuffix.endsWith(suffix);
	} else {
	match = hostName.endsWith(cn.substring(1));
	}
	if (match) {
	// I f we ’ r e i n s t r i c t mode ,
	// [ ∗.foo.com] is not allowed to match [a.b.foo.com]
	match = countDots(hostName) == countDots(cn);
	}
	return match;
	}

	private static int countDots(final String data) {
	int dots = 0;
	for (int i = 0; i < data.length(); i++) {
	if (data.charAt(i) == '.') {
	dots += 1;
	}
	}
	return dots;
	}


	private static String[] getCNs(X509Certificate cert) {
	// Note: toString() seems to do a better job than getName()
	//
	// For example, getName() gives me this:
	// 1.2.840.113549.1.9.1=#16166a756c6975736461766965734063756362632e636f6d
	//
	// whereas toString() gives me this:
	// EMAILADDRESS=juliusdavies@cucbc.com
	String subjectPrincipal = cert.getSubjectX500Principal().toString();

	return getCNs(subjectPrincipal);

	}
	private static String[] getCNs(String subjectPrincipal) {
	if (subjectPrincipal == null) {
	return null;
	}
	final List cns = new ArrayList();
	try {
	final LdapName subjectDN = new LdapName(subjectPrincipal);
	final List rdns = subjectDN.getRdns();
	for (int i = rdns.size() - 1; i >= 0; i--) {
	final Rdn rds = (Rdn) rdns.get(i);
	final Attributes attributes = rds.toAttributes();
	final Attribute cn = attributes.get("cn");
	if (cn != null) {
	try {
	final Object value = cn.get();
	if (value != null) {
	cns.add(value.toString());
	}
	}
	catch (NamingException ignore) {}
	}
	}
	}
	catch (InvalidNameException ignore) { }
	return cns.isEmpty() ? null : (String[]) cns.toArray(new String[ cns.size() ]);
	}

	}