Handshake failures (#5624)

* BAEL-2250: Adding files for the article on SSL handshake failure.

* BAEL-2250 cleanup formatting

* Applied review feedback on the article.

* Adding cipher suite and protocol selection in server and client

* Corrected some code conventions.

* Revert: BAEL-2250 cleanup formatting

* Made further changes for the review comments on the tutorial.

* Fixed some formatting issues.

core-java/src/main/java/com/baeldung/ssl/example/SimpleClient.java

@@ -8,22 +8,26 @@ import java.net.Socket;
 import javax.net.SocketFactory;
 import javax.net.ssl.SSLSocket;
 import javax.net.ssl.SSLSocketFactory;
+import javax.net.ssl.SSLParameters;
 
 public class SimpleClient {
-    static void startClient(String host, int port) throws IOException {
+    static String startClient(String host, int port) throws IOException {
         SocketFactory factory = SSLSocketFactory.getDefault();
+
         try (Socket connection = factory.createSocket(host, port)) {
             ((SSLSocket) connection).setEnabledCipherSuites(
               new String[] { "TLS_DHE_DSS_WITH_AES_256_CBC_SHA256"});
             ((SSLSocket) connection).setEnabledProtocols(
               new String[] { "TLSv1.2"});
-            BufferedReader input = new BufferedReader(
+            SSLParameters sslParams = new SSLParameters();
-              new InputStreamReader(connection.getInputStream()));
+            sslParams.setEndpointIdentificationAlgorithm("HTTPS");
-            System.out.println(input.readLine());
+            ((SSLSocket) connection).setSSLParameters(sslParams);
+            BufferedReader input = new BufferedReader(new InputStreamReader(connection.getInputStream()));
+            return input.readLine();
         }
     }
 
     public static void main(String[] args) throws IOException {
-        startClient("localhost", 1234);
+        System.out.println(startClient("localhost", 8443));
     }
 }

core-java/src/main/java/com/baeldung/ssl/example/SimpleServer.java

@@ -4,7 +4,6 @@ import java.io.IOException;
 import java.io.PrintWriter;
 import java.net.ServerSocket;
 import java.net.Socket;
-import java.util.Date;
 
 import javax.net.ServerSocketFactory;
 import javax.net.ssl.SSLServerSocket;
@@ -13,6 +12,7 @@ import javax.net.ssl.SSLServerSocketFactory;
 public class SimpleServer {
     static void startServer(int port) throws IOException {
         ServerSocketFactory factory = SSLServerSocketFactory.getDefault();
+
         try (ServerSocket listener = factory.createServerSocket(port)) {
             ((SSLServerSocket) listener).setNeedClientAuth(true);
             ((SSLServerSocket) listener).setEnabledCipherSuites(
@@ -22,13 +22,13 @@ public class SimpleServer {
             while (true) {
                 try (Socket socket = listener.accept()) {
                     PrintWriter out = new PrintWriter(socket.getOutputStream(), true);
-                    out.println(new Date().toString());
+                    out.println("Hello World!");
                 }
             }
         }
     }
 
     public static void main(String[] args) throws IOException {
-        startServer(1234);
+        startServer(8443);
     }
-}
+}