title: Getting SocketTimeoutException while trying to resolve SSLHandshakeException
body: <p>I have been getting the following exception :</p>
  
  <pre><code>sun.security.validator.ValidatorException: PKIX path building failed: 
  sun.security.provider.certpath.SunCertPathBuilderException: unable to find
  valid certification path to requested target
  </code></pre>
  
  <p>To resolve this, I found that I need to install some kind of certificate <em>(I don't understand what it is)</em> by running this program : <a href="https://code.google.com/p/java-use-examples/source/browse/trunk/src/com/aw/ad/util/InstallCert.java" rel="nofollow"><strong><em>(source)</em></strong></a></p>
  
  <pre><code>/*
   * Copyright 2006 Sun Microsystems, Inc.  All Rights Reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   *   - Redistributions of source code must retain the above copyright
   *     notice, this list of conditions and the following disclaimer.
   *
   *   - Redistributions in binary form must reproduce the above copyright
   *     notice, this list of conditions and the following disclaimer in the
   *     documentation and/or other materials provided with the distribution.
   *
   *   - Neither the name of Sun Microsystems nor the names of its
   *     contributors may be used to endorse or promote products derived
   *     from this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
   * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
   * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
   * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
   * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
   * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
   * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
   * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
   * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  /**
   * http://blogs.sun.com/andreas/resource/InstallCert.java
   * Use:
   * java InstallCert hostname
   * Example:
   *% java InstallCert ecc.fedora.redhat.com
   */
  
  import javax.net.ssl.*;
  import java.io.*;
  import java.security.KeyStore;
  import java.security.MessageDigest;
  import java.security.cert.CertificateException;
  import java.security.cert.X509Certificate;
  
  /**
   * Class used to add the server's certificate to the KeyStore
   * with your trusted certificates.
   */
  public class InstallCert {
  
      public static void main(String[] args) throws Exception {
          String host;
          int port;
          char[] passphrase;
          if ((args.length == 1) || (args.length == 2)) {
              String[] c = args[0].split(":");
              host = c[0];
              port = (c.length == 1) ? 443 : Integer.parseInt(c[1]);
              String p = (args.length == 1) ? "changeit" : args[1];
              passphrase = p.toCharArray();
          } else {
              System.out.println("Usage: java InstallCert &lt;host&gt;[:port] [passphrase]");
              return;
          }
  
          File file = new File("jssecacerts");
          if (file.isFile() == false) {
              char SEP = File.separatorChar;
              File dir = new File(System.getProperty("java.home") + SEP
                      + "lib" + SEP + "security");
              file = new File(dir, "jssecacerts");
              if (file.isFile() == false) {
                  file = new File(dir, "cacerts");
              }
          }
          System.out.println("Loading KeyStore " + file + "...");
          InputStream in = new FileInputStream(file);
          KeyStore ks = KeyStore.getInstance(KeyStore.getDefaultType());
          ks.load(in, passphrase);
          in.close();
  
          SSLContext context = SSLContext.getInstance("TLS");
          TrustManagerFactory tmf =
                  TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());
          tmf.init(ks);
          X509TrustManager defaultTrustManager = (X509TrustManager) tmf.getTrustManagers()[0];
          SavingTrustManager tm = new SavingTrustManager(defaultTrustManager);
          context.init(null, new TrustManager[]{tm}, null);
          SSLSocketFactory factory = context.getSocketFactory();
  
          System.out.println("Opening connection to " + host + ":" + port + "...");
          SSLSocket socket = (SSLSocket) factory.createSocket(host, port);
          socket.setSoTimeout(10000);
          try {
              System.out.println("Starting SSL handshake...");
              socket.startHandshake();
              socket.close();
              System.out.println();
              System.out.println("No errors, certificate is already trusted");
          } catch (SSLException e) {
              System.out.println();
              e.printStackTrace(System.out);
          }
  
          X509Certificate[] chain = tm.chain;
          if (chain == null) {
              System.out.println("Could not obtain server certificate chain");
              return;
          }
  
          BufferedReader reader =
                  new BufferedReader(new InputStreamReader(System.in));
  
          System.out.println();
          System.out.println("Server sent " + chain.length + " certificate(s):");
          System.out.println();
          MessageDigest sha1 = MessageDigest.getInstance("SHA1");
          MessageDigest md5 = MessageDigest.getInstance("MD5");
          for (int i = 0; i &lt; chain.length; i++) {
              X509Certificate cert = chain[i];
              System.out.println
                      (" " + (i + 1) + " Subject " + cert.getSubjectDN());
              System.out.println("   Issuer  " + cert.getIssuerDN());
              sha1.update(cert.getEncoded());
              System.out.println("   sha1    " + toHexString(sha1.digest()));
              md5.update(cert.getEncoded());
              System.out.println("   md5     " + toHexString(md5.digest()));
              System.out.println();
          }
  
          System.out.println("Enter certificate to add to trusted keystore or 'q' to quit: [1]");
          String line = reader.readLine().trim();
          int k;
          try {
              k = (line.length() == 0) ? 0 : Integer.parseInt(line) - 1;
          } catch (NumberFormatException e) {
              System.out.println("KeyStore not changed");
              return;
          }
  
          X509Certificate cert = chain[k];
          String alias = host + "-" + (k + 1);
          ks.setCertificateEntry(alias, cert);
  
          OutputStream out = new FileOutputStream("jssecacerts");
          ks.store(out, passphrase);
          out.close();
  
          System.out.println();
          System.out.println(cert);
          System.out.println();
          System.out.println
                  ("Added certificate to keystore 'jssecacerts' using alias '"
                          + alias + "'");
      }
  
      private static final char[] HEXDIGITS = "0123456789abcdef".toCharArray();
  
      private static String toHexString(byte[] bytes) {
          StringBuilder sb = new StringBuilder(bytes.length * 3);
          for (int b : bytes) {
              b &amp;= 0xff;
              sb.append(HEXDIGITS[b &gt;&gt; 4]);
              sb.append(HEXDIGITS[b &amp; 15]);
              sb.append(' ');
          }
          return sb.toString();
      }
  
      private static class SavingTrustManager implements X509TrustManager {
  
          private final X509TrustManager tm;
          private X509Certificate[] chain;
  
          SavingTrustManager(X509TrustManager tm) {
              this.tm = tm;
          }
  
          public X509Certificate[] getAcceptedIssuers() {
              throw new UnsupportedOperationException();
          }
  
          public void checkClientTrusted(X509Certificate[] chain, String authType)
                  throws CertificateException {
              throw new UnsupportedOperationException();
          }
  
          public void checkServerTrusted(X509Certificate[] chain, String authType)
                  throws CertificateException {
              this.chain = chain;
              tm.checkServerTrusted(chain, authType);
          }
      }
  
  }
  </code></pre>
  
  <p>as <code>java InstallCert localhost:8081</code> , where <code>localhost</code> is the address where the server is running and port number is the port number of the server. <em>(I am running tomcat server)</em></p>
  
  <p>But when I run this after compiling, I get to see this :</p>
  
  <pre><code>Loading KeyStore C:\Program Files\Java\jre7\lib\security\cacerts...
  Opening connection to localhost:8081...
  Starting SSL handshake...
  Exception in thread "main" java.net.SocketTimeoutException: Read timed out
          at java.net.SocketInputStream.socketRead0(Native Method)
          at java.net.SocketInputStream.read(Unknown Source)
          at java.net.SocketInputStream.read(Unknown Source)
          at sun.security.ssl.InputRecord.readFully(Unknown Source)
          at sun.security.ssl.InputRecord.read(Unknown Source)
          at sun.security.ssl.SSLSocketImpl.readRecord(Unknown Source)
          at sun.security.ssl.SSLSocketImpl.performInitialHandshake(Unknown Source)
          at sun.security.ssl.SSLSocketImpl.startHandshake(Unknown Source)
          at sun.security.ssl.SSLSocketImpl.startHandshake(Unknown Source)
          at InstallCert.main(InstallCert.java:97)
  </code></pre>
  
  <p>Now there are 2 questions I want to ask :</p>
  
  <ul>
  <li>What is the aim of this program ? What does it want to achieve ?</li>
  <li>What could be the reason for <code>java.net.SocketTimeoutException</code> ?</li>
  </ul>