1 files changed, 107 insertions, 0 deletions
diff --git a/src/main/java/com/btr/proxy/search/wpad/dhcp/DHCPSocket.java b/src/main/java/com/btr/proxy/search/wpad/dhcp/DHCPSocket.java
new file mode 100644
index 0000000..6dbe2bf
--- /dev/null
+++ b/src/main/java/com/btr/proxy/search/wpad/dhcp/DHCPSocket.java
@@ -0,0 +1,107 @@
+package com.btr.proxy.search.wpad.dhcp;
+
+import java.io.IOException;
+import java.net.DatagramPacket;
+import java.net.DatagramSocket;
+import java.net.InetAddress;
+import java.net.Socket;
+import java.net.SocketException;
+import java.net.UnknownHostException;
+
+/**
+ * This class represents a Socket for sending DHCP Messages
+ * 
+ * @author Jason Goldschmidt and Simon Frankenberger
+ * 
+ * @see java.net.DatagramSocket
+ */
+
+public class DHCPSocket extends DatagramSocket {
+	/**
+	 * Default socket timeout (1 second)
+	 */
+	private int SOCKET_TIMEOUT = 5000;
+	
+	/**
+	 * Default MTU (Maximum Transmission Unit) for ethernet (in bytes)
+	 */
+	private int mtu = 1500;
+	
+	/** 
+	 * Constructor for creating DHCPSocket on a specific port on the local
+	 * machine.
+	 * 
+	 * @param inPort The port for the application to bind.
+	 * 
+	 * @throws SocketException As thrown by the {@link Socket} constructor
+	 */
+	public DHCPSocket(int inPort) throws SocketException {
+		super(inPort);
+		setSoTimeout(this.SOCKET_TIMEOUT);
+	}
+	
+	/**
+	 * Sets the Maximum Transfer Unit for the UDP DHCP Packets to be set.
+	 * 
+	 * @param inSize Integer representing desired MTU
+	 */
+	public void setMTU(int inSize) {
+		this.mtu = inSize;
+	}
+	
+	/**
+	 * Returns the set MTU for this socket
+	 * 
+	 * @return The Maximum Transfer Unit set for this socket
+	 */
+	public int getMTU() {
+		return this.mtu;
+	}
+	
+	/**
+	 * Sends a DHCPMessage object to a predifined host.
+	 * 
+	 * @param inMessage Well-formed DHCPMessage to be sent to a server
+	 * 
+	 * @throws IOException If the message could not be sent.
+	 */
+	public synchronized void send(DHCPMessage inMessage) throws IOException {
+		byte data[] = new byte[this.mtu];
+		data = inMessage.externalize();
+		InetAddress dest = null;
+		try {
+			dest = InetAddress.getByName(inMessage.getDestinationAddress());
+		}
+		catch (UnknownHostException e) {
+		}
+		
+		DatagramPacket outgoing = new DatagramPacket(data, data.length, dest,
+		    inMessage.getPort());
+		
+		send(outgoing); // send outgoing message
+	}
+	
+	/** 
+	 * Receives a datagram packet containing a DHCP Message into
+	 * a DHCPMessage object.
+	 * 
+	 * @return <code>true</code> if message is received, 
+	 *         <code>false</code> if timeout occurs.  
+	 * @param outMessage DHCPMessage object to receive new message into
+	 */
+	public synchronized boolean receive(DHCPMessage outMessage) {
+		try {
+			DatagramPacket incoming = new DatagramPacket(new byte[this.mtu],
+			    this.mtu);
+			//gSocket.
+			receive(incoming); // block on receive for SOCKET_TIMEOUT
+			
+			outMessage.internalize(incoming.getData());
+		}
+		catch (java.io.IOException e) {
+			e.printStackTrace();
+			return false;
+		} // end catch
+		return true;
+	}
+}