Changing WebSocket Masking Key to use SecureRandom #255 (#259)

* Fixing typo in IMqttClient.java

Signed-off-by: James Sutton <james.sutton@uk.ibm.com>

* Issue #213

Signed-off-by: James Sutton <james.sutton@uk.ibm.com>

* Issue #249: Null Check for reconnect timer & Connect options

Signed-off-by: James Sutton <james.sutton@uk.ibm.com>

* Changing WebSocket Masking Key to use SecureRandom

Signed-off-by: James Sutton <james.sutton@uk.ibm.com>

Author: jpwsutton

org.eclipse.paho.client.mqttv3/src/main/java/org/eclipse/paho/client/mqttv3/internal/websocket/WebSocketFrame.java

@@ -18,7 +18,7 @@
 import java.io.IOException;
 import java.io.InputStream;
 import java.nio.ByteBuffer;
-import java.util.Random;
+import java.security.SecureRandom;
 
 public class WebSocketFrame {
 
@@ -291,11 +291,11 @@ public static void appendFinAndOpCode(ByteBuffer buffer, byte opcode, boolean fi
 	 * @return ByteArray containing the key;
 	 */
 	public static byte[] generateMaskingKey(){
-		Random randomGenerator = new Random();
-		int a = randomGenerator.nextInt(255);
-		int b = randomGenerator.nextInt(255);
-		int c = randomGenerator.nextInt(255);
-		int d = randomGenerator.nextInt(255);
+		SecureRandom secureRandomGenerator = new SecureRandom();
+		int a = secureRandomGenerator.nextInt(255);
+		int b = secureRandomGenerator.nextInt(255);
+		int c = secureRandomGenerator.nextInt(255);
+		int d = secureRandomGenerator.nextInt(255);
 		return new byte[] {(byte) a,(byte) b,(byte) c,(byte) d};
 	}