Begin implementation of lumberjack protocol.

.classpath

@@ -22,5 +22,10 @@
 			<attribute name="maven.pomderived" value="true"/>
 		</attributes>
 	</classpathentry>
+	<classpathentry excluding="**" kind="src" output="target/test-classes" path="src/test/resources">
+		<attributes>
+			<attribute name="maven.pomderived" value="true"/>
+		</attributes>
+	</classpathentry>
 	<classpathentry kind="output" path="target/classes"/>
 </classpath>

src/main/java/info/fetter/logstashforwarder/protocol/LumberjackClient.java

@@ -0,0 +1,107 @@
+package info.fetter.logstashforwarder.protocol;
+
+import java.io.BufferedOutputStream;
+import java.io.DataInputStream;
+import java.io.DataOutputStream;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.security.KeyManagementException;
+import java.security.KeyStore;
+import java.security.KeyStoreException;
+import java.security.NoSuchAlgorithmException;
+import java.security.cert.CertificateException;
+import java.util.Map;
+
+import javax.net.SocketFactory;
+import javax.net.ssl.SSLContext;
+import javax.net.ssl.SSLSocket;
+import javax.net.ssl.TrustManagerFactory;
+
+public class LumberjackClient {
+	private final static byte PROTOCOL_VERSION = 0x31;
+	private final static byte FRAME_ACK = 0x41;
+	private final static byte FRAME_WINDOW_SIZE = 0x57;
+	private final static byte FRAME_DATA = 0x44;
+	
+	private SSLSocket socket;
+	private KeyStore keyStore;
+	private String server;
+	private int port;
+	private DataOutputStream output;
+	private DataInputStream input;
+	private int sequence = 1;
+	
+	public LumberjackClient(String keyStorePath, String server, int port) throws NoSuchAlgorithmException, CertificateException, FileNotFoundException, IOException, KeyStoreException, KeyManagementException {
+		this.server = server;
+		this.port = port;
+		
+		keyStore = KeyStore.getInstance("JKS");
+		keyStore.load(new FileInputStream(keyStorePath), null);
+		
+		TrustManagerFactory tmf = TrustManagerFactory.getInstance("PKIX");
+		tmf.init(keyStore);
+
+		SSLContext context = SSLContext.getInstance("TLS");
+		context.init(null, tmf.getTrustManagers(), null);
+		
+		SocketFactory socketFactory = context.getSocketFactory();
+		socket = (SSLSocket)socketFactory.createSocket(this.server, this.port);
+		socket.setUseClientMode(true);
+		socket.startHandshake();
+		
+		output = new DataOutputStream(new BufferedOutputStream(socket.getOutputStream()));
+		input = new DataInputStream(socket.getInputStream());
+	}
+	
+	public int sendWindowSizeFrame(int size) throws IOException {
+		output.writeByte(PROTOCOL_VERSION);
+		output.writeByte(FRAME_WINDOW_SIZE);
+		output.writeInt(size);
+		output.flush();
+		return 6;
+	}
+	
+	private int sendDataFrame(DataOutputStream output, Map<String,byte[]> keyValues) throws IOException {
+		output.writeByte(PROTOCOL_VERSION);
+		output.writeByte(FRAME_DATA);
+		output.writeInt(sequence++);
+		output.writeInt(keyValues.size());
+		int bytesSent = 10;
+		for(String key : keyValues.keySet()) {
+			int keyLength = key.length();
+			output.writeInt(keyLength);
+			bytesSent += 4;
+			output.write(key.getBytes());
+			bytesSent += keyLength;
+			byte[] value = keyValues.get(key);
+			output.writeInt(value.length);
+			bytesSent += 4;
+			output.write(value);
+			bytesSent += value.length;
+		}
+		output.flush();
+		return bytesSent;
+	}
+	
+	public int sendDataFrameInSocket(Map<String,byte[]> keyValues) throws IOException {
+		return sendDataFrame(output, keyValues);
+	}
+	
+	public int readAckFrame() throws IOException {
+		byte protocolVersion = input.readByte();
+		if(protocolVersion != PROTOCOL_VERSION) {
+			throw new IOException("Protocol version should be 1, received " + protocolVersion);
+		}
+		byte frameType = input.readByte();
+		if(frameType != FRAME_ACK) {
+			throw new IOException("Frame type should be Ack, received " + frameType);
+		}
+		int sequenceNumber = input.readInt();
+		return sequenceNumber;
+	}
+	
+	public void close() throws IOException {
+		socket.close();
+	}
+}