Add hashsum

src/clientP2P/ClientManagementTCP.java

@@ -21,12 +21,18 @@ import java.nio.file.Files;
 import java.io.File;
 import java.nio.file.Paths;
 import java.nio.file.StandardOpenOption;
+import java.util.Arrays;
 import protocolP2P.ProtocolP2PPacketTCP;
 import protocolP2P.Payload;
 import protocolP2P.RequestResponseCode;
 import protocolP2P.FileList;
 import protocolP2P.FilePart;
 import protocolP2P.LoadRequest;
+import protocolP2P.HashAlgorithm;
+import protocolP2P.HashRequest;
+import protocolP2P.HashResponse;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
 
 /** Implementation of P2P-JAVA-PROJECT CLIENT
  * @author	Louis Royer
@@ -134,8 +140,30 @@ public class ClientManagementTCP implements Runnable {
 	 * @throws	EmptyFile
 	 */
 	private void download(String filename) throws EmptyFile, NotFound, InternalError, UnknownHostException, IOException, SocketClosed, TransmissionError, ProtocolError, VersionError, SizeError, InternalRemoteError, ProtocolRemoteError, VersionRemoteError {
+		byte [] hash512;
 		final long MAX_PARTIAL_SIZE = 4096;
-		ProtocolP2PPacketTCP d = new ProtocolP2PPacketTCP((Payload) new LoadRequest(filename, 0, MAX_PARTIAL_SIZE));
+		HashAlgorithm[] hashesAlgo = new HashAlgorithm[1];
+		hashesAlgo[0] = HashAlgorithm.SHA512;
+		ProtocolP2PPacketTCP d = new ProtocolP2PPacketTCP((Payload) new HashRequest(filename, hashesAlgo));
+		d.sendRequest((Object)socket);
+		try {
+			Payload pHash = d.receiveResponse().getPayload();
+			assert pHash instanceof HashResponse : "This payload must be instance of HashResponse";
+			if (!(pHash instanceof HashResponse)) {
+				throw new InternalError();
+			} else { 
+				hash512 = ((HashResponse)pHash).getHash(HashAlgorithm.SHA512);
+				if (hash512.length == 0) {
+					System.err.println("Error: server do not support sha512 hashes");
+					throw new InternalError();
+				}
+			}
+		} catch (EmptyDirectory e) {
+			System.err.println("Error: empty directory, but request was not LIST_REQUEST");
+			throw new ProtocolError();
+		}
+
+		d = new ProtocolP2PPacketTCP((Payload) new LoadRequest(filename, 0, MAX_PARTIAL_SIZE));
 		d.sendRequest((Object)socket);
 		boolean fileFullyWritten = false;
 		long offset = 0;
@@ -199,6 +227,10 @@ public class ClientManagementTCP implements Runnable {
 				throw new ProtocolError();
 			}
 		} while(!fileFullyWritten);
+		if (!Arrays.equals(hash512, computeHashsum(filename, HashAlgorithm.SHA512))) {
+			System.err.println("Error: Hashsum does not match");
+			throw new InternalError();
+		}
 		socket.close();
 	}
 
@@ -234,4 +266,20 @@ public class ClientManagementTCP implements Runnable {
 			throw new ProtocolError();
 		}
 	}
+
+	/** Compute Hashsum of a file.
+	 * @param	filename
+	 * @return	hashsum
+	 */
+	private byte[] computeHashsum(String filename, HashAlgorithm h) {
+		try {
+			MessageDigest md = MessageDigest.getInstance(HashAlgorithm.SHA512.getName());
+			return md.digest(Files.readAllBytes(Paths.get(baseDirectory + filename)));
+		} catch (NoSuchAlgorithmException e) {
+			System.out.println("Error: " + h.getName() + " not supported");
+		} catch (IOException e) {
+			System.out.println("Error: cannot read " + filename);
+		}
+		return new byte[0];
+	}
 }

src/clientP2P/ClientManagementUDP.java

@@ -20,12 +20,18 @@ import java.nio.file.Files;
 import java.io.File;
 import java.nio.file.Paths;
 import java.nio.file.StandardOpenOption;
+import java.util.Arrays;
 import protocolP2P.ProtocolP2PPacketUDP;
 import protocolP2P.Payload;
 import protocolP2P.RequestResponseCode;
 import protocolP2P.FileList;
 import protocolP2P.FilePart;
 import protocolP2P.LoadRequest;
+import protocolP2P.HashAlgorithm;
+import protocolP2P.HashRequest;
+import protocolP2P.HashResponse;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
 
 /** Implementation of P2P-JAVA-PROJECT CLIENT
  * @author	Louis Royer
@@ -121,8 +127,30 @@ public class ClientManagementUDP implements Runnable {
 	 * @throws	EmptyFile
 	 */
 	private void download(String filename) throws EmptyFile, NotFound, InternalError, UnknownHostException, IOException, TransmissionError, ProtocolError, VersionError, SizeError, InternalRemoteError, ProtocolRemoteError, VersionRemoteError {
+		byte[] hash512;
 		final long MAX_PARTIAL_SIZE = 4096;
-		ProtocolP2PPacketUDP d = new ProtocolP2PPacketUDP((Payload) new LoadRequest(filename, 0, MAX_PARTIAL_SIZE));
+		HashAlgorithm[] hashesAlgo = new HashAlgorithm[1];
+		hashesAlgo[0] = HashAlgorithm.SHA512;
+		ProtocolP2PPacketUDP d = new ProtocolP2PPacketUDP((Payload) new HashRequest(filename, hashesAlgo));
+		d.sendRequest((Object)socket);
+		try {
+			Payload pHash = d.receiveResponse().getPayload();
+			assert pHash instanceof HashResponse : "This payload must be instance of HashResponse";
+			if (!(pHash instanceof HashResponse)) {
+				throw new InternalError();
+			} else { 
+				hash512 = ((HashResponse)pHash).getHash(HashAlgorithm.SHA512);
+				if (hash512.length == 0) {
+					System.err.println("Error: server do not support sha512 hashes");
+					throw new InternalError();
+				}
+			}
+		} catch (EmptyDirectory e) {
+			System.err.println("Error: empty directory, but request was not LIST_REQUEST");
+			throw new ProtocolError();
+		}
+
+		d = new ProtocolP2PPacketUDP((Payload) new LoadRequest(filename, 0, MAX_PARTIAL_SIZE));
 		d.sendRequest((Object)socket);
 		boolean fileFullyWritten = false;
 		long offset = 0;
@@ -186,6 +214,10 @@ public class ClientManagementUDP implements Runnable {
 				throw new ProtocolError();
 			}
 		} while(!fileFullyWritten);
+		if (!Arrays.equals(hash512, computeHashsum(filename, HashAlgorithm.SHA512))) {
+			System.err.println("Error: Hashsum does not match");
+			throw new InternalError();
+		}
 	}
 
 	/** list server’s directory content
@@ -219,4 +251,20 @@ public class ClientManagementUDP implements Runnable {
 			throw new ProtocolError();
 		}
 	}
+
+	/** Compute Hashsum of a file.
+	 * @param	filename
+	 * @return	hashsum
+	 */
+	private byte[] computeHashsum(String filename, HashAlgorithm h) {
+		try {
+			MessageDigest md = MessageDigest.getInstance(HashAlgorithm.SHA512.getName());
+			return md.digest(Files.readAllBytes(Paths.get(baseDirectory + filename)));
+		} catch (NoSuchAlgorithmException e) {
+			System.out.println("Error: " + h.getName() + " not supported");
+		} catch (IOException e) {
+			System.out.println("Error: cannot read " + filename);
+		}
+		return new byte[0];
+	}
 }

src/protocolP2P/HashAlgorithm.java

@@ -1,6 +1,7 @@
 package protocolP2P;
 import java.util.HashMap;
 import java.util.Map;
+import tools.BytesArrayTools;
 
 /** HashAlgorithm enum.
  * @author	Louis Royer
@@ -14,16 +15,16 @@ public enum HashAlgorithm {
 	
 	private String name;
 	/* To be able to convert name to enum */
-	private static final Map<Byte, HashAlgorithm> BY_CODE = new HashMap<>();
+	private static final Map<String, HashAlgorithm> BY_NAME = new HashMap<>();
 	/* Initialization of HashMap */
 	static {
 		for (HashAlgorithm h: values()) {
-			assert !BY_CODE.containsKey(Byte.valueOf(h.name)) : "Duplicate in " + HashAlgorithm.class.getCanonicalName();
+			assert !BY_NAME.containsKey(h.name) : "Duplicate in " + HashAlgorithm.class.getCanonicalName();
-			BY_CODE.put(Byte.valueOf(h.name), h);
+			BY_NAME.put(h.name, h);
 		}
 	}
 
-	HashAlgorithm(String name) {
+	private HashAlgorithm(String name) {
 		this.name = name;
 	}
 
@@ -37,11 +38,13 @@ public enum HashAlgorithm {
 	 * @throws	InterlanError
 	 */
 	protected static HashAlgorithm fromName(String name) throws InternalError {
-		HashAlgorithm h = BY_CODE.get(Byte.valueOf(name));
+		HashAlgorithm h = BY_NAME.get(BytesArrayTools.cleanStrings(name));
+		assert h != null : "Bad algorithm name: " + name;
 		if (h == null) {
 			throw new InternalError();
 		}
 		return h;
+		
 	}
 	
 }

src/protocolP2P/HashRequest.java

@@ -70,6 +70,7 @@ public class HashRequest extends Payload {
 		try {
 			String[] l = (new String(packet, FILENAME_POSITION + filenameSize, size, "UTF-8")).split("\n");
 			int i = 0;
+			algoList = new HashAlgorithm[l.length];
 			for(String algo : l) {
 				algoList[i] = HashAlgorithm.fromName(algo);
 				i++;
@@ -90,6 +91,9 @@ public class HashRequest extends Payload {
 		int filenameSize = filename.length();
 		int size = FILENAME_POSITION + filenameSize;
 		for (HashAlgorithm h : algoList) {
+			if (h == null) {
+				continue;
+			}
 			size += h.getName().length();
 			size += 1; // size for '\n'
 		}
@@ -117,6 +121,9 @@ public class HashRequest extends Payload {
 		}
 		boolean firstIter = true;
 		for(HashAlgorithm h : algoList) {
+			if (h == null) {
+				continue;
+			}
 			String s = h.getName();
 			if (!firstIter) {
 				firstIter = false;

src/protocolP2P/HashResponse.java

@@ -8,10 +8,7 @@ import exception.SizeError;
 import exception.ProtocolError;
 import exception.InternalError;
 import tools.BytesArrayTools;
-import java.security.MessageDigest;
+
-import java.security.DigestInputStream;
-import java.nio.file.Files;
-import java.nio.file.Paths;
 
 /** Representation of payload for hash response.
  * @author	Louis Royer
@@ -22,7 +19,7 @@ import java.nio.file.Paths;
 
 public class HashResponse extends Payload {
 	private String filename;
-	private Map<HashAlgorithm, String> hashes;
+	private Map<HashAlgorithm, byte[]> hashes = new HashMap<>();
 	private static final int FILENAME_SIZE_POSITION = PAYLOAD_START_POSITION;
 	private static final int FILENAME_POSITION = FILENAME_SIZE_POSITION + 4;
 	
@@ -32,7 +29,7 @@ public class HashResponse extends Payload {
 	 * @throws	InternalError
 	 * 
 	 */
-	public HashResponse(String filename, Map<HashAlgorithm, String> hashes) throws InternalError {
+	public HashResponse(String filename, Map<HashAlgorithm, byte[]> hashes) throws InternalError {
 		super(RequestResponseCode.HASH_RESPONSE);
 		/* assert to help debugging */
 		assert filename.length() != 0 : "Size of filename in HashResponse must not be empty";
@@ -81,9 +78,13 @@ public class HashResponse extends Payload {
 				String algoName = new String(packet, start, algoNameSize, "UTF-8");
 				start += algoNameSize;
 				int hashSize = BytesArrayTools.readInt(packet, start);
-				start += 8;
+				start += 4;
 				if (hashSize != 0) {
-					hashes.put(HashAlgorithm.fromName(algoName), new String(packet, start, hashSize, "UTF-8"));
+					byte[] b = new byte[hashSize];
+					for (int i=0;i<hashSize;i++) {
+						b[i] = packet[start+i];
+					}
+					hashes.put(HashAlgorithm.fromName(algoName), b);
 				}
 				start += hashSize;
 			} catch (UnsupportedEncodingException e) {
@@ -106,8 +107,8 @@ public class HashResponse extends Payload {
 		for (HashAlgorithm h : hashes.keySet()) {
 			size += 4 + h.getName().length();
 		}
-		for (String s : hashes.values()) {
+		for (byte[] s : hashes.values()) {
-			size += 4 + s.length();
+			size += 4 + s.length;
 		}
 		byte[] packet = new byte[size + 1]; // java initialize all to zero
 		
@@ -144,22 +145,17 @@ public class HashResponse extends Payload {
 			} catch (UnsupportedEncodingException e) {
 				throw new InternalError();
 			}
-			s = hashes.get(s);
+			byte[] hashb = hashes.get(HashAlgorithm.fromName(s));
-			if (s == null) {
+			if (hashb.length == 0) {
 				BytesArrayTools.write(packet, bCount, (int)0);
 				bCount += 4;
 			} else {
-				BytesArrayTools.write(packet, bCount, (int)s.length());
+				BytesArrayTools.write(packet, bCount, (int)hashb.length);
 				bCount +=4;
 				// copy hash
-				try {
+				for(byte b : hashb) {
-					byte[] sb = s.getBytes("UTF-8");
+					packet[bCount] = b;
-					for(byte b : sb) {
+					bCount += 1;
-						packet[bCount] = b;
-						bCount += 1;
-					}
-				} catch (UnsupportedEncodingException e) {
-					throw new InternalError();
 				}
 			}
 		}
@@ -170,8 +166,13 @@ public class HashResponse extends Payload {
 	 * @param hashAlgo	HashAlgorithm to return hash from
 	 * @return	hash
 	 */
-	public String getHash(HashAlgorithm hashAlgo) {
+	public byte[] getHash(HashAlgorithm hashAlgo) {
-		return hashes.get(hashAlgo);
+		byte[] b = hashes.get(hashAlgo);
+		if (b == null) {
+			return new byte[0];
+		} else {
+			return b;
+		}
 	}
 
 	/** filename getter.

src/protocolP2P/ProtocolP2PPacketTCP.java

@@ -137,6 +137,7 @@ public class ProtocolP2PPacketTCP extends ProtocolP2PPacket {
 				case EMPTY_FILE:
 				case LOAD_RESPONSE:
 				case LIST_RESPONSE:
+				case HASH_RESPONSE:
 					// we were expecting a request, but we are receiving a response
 					throw new ProtocolError();
 				default :
@@ -281,6 +282,12 @@ public class ProtocolP2PPacketTCP extends ProtocolP2PPacket {
 			case LOAD_REQUEST:
 				payload = (Payload) new LoadRequest(packet);
 				break;
+			case HASH_REQUEST:
+				payload = (Payload) new HashRequest(packet);
+				break;
+			case HASH_RESPONSE:
+				payload = (Payload) new HashResponse(packet);
+				break;
 			default:
 				payload = new Payload(packet); // this can throw TransmissionError
 				break;

src/protocolP2P/ProtocolP2PPacketUDP.java

@@ -129,6 +129,7 @@ public class ProtocolP2PPacketUDP extends ProtocolP2PPacket {
 				case EMPTY_FILE:
 				case LOAD_RESPONSE:
 				case LIST_RESPONSE:
+				case HASH_RESPONSE:
 					// we were expecting a request, but we are receiving a response
 					throw new ProtocolError();
 				default :
@@ -277,6 +278,12 @@ public class ProtocolP2PPacketUDP extends ProtocolP2PPacket {
 			case LOAD_REQUEST:
 				payload = (Payload) new LoadRequest(packet);
 				break;
+			case HASH_REQUEST:
+				payload = (Payload) new HashRequest(packet);
+				break;
+			case HASH_RESPONSE:
+				payload = (Payload) new HashResponse(packet);
+				break;
 			default:
 				payload = new Payload(packet); // this can throw TransmissionError
 				break;

src/serverP2P/ServerManagementTCP.java

@@ -6,6 +6,8 @@ import java.net.InetAddress;
 import java.net.SocketException;
 import java.nio.file.Paths;
 import java.nio.file.Files;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
 import java.net.ServerSocket;
 import java.net.Socket;
 import protocolP2P.ProtocolP2PPacketTCP;
@@ -30,6 +32,11 @@ import remoteException.EmptyFile;
 import java.util.Arrays;
 import tools.Logger;
 import tools.LogLevel;
+import java.util.HashMap;
+import java.util.Map;
+import protocolP2P.HashAlgorithm;
+import protocolP2P.HashRequest;
+import protocolP2P.HashResponse;
 
 
 /** Implementation of P2P-JAVA-PROJECT VERSION 1.0 protocol for TCP.
@@ -41,6 +48,7 @@ import tools.LogLevel;
 public class ServerManagementTCP implements Runnable {
 
 	private String[] fileList;
+	private Map<String, byte[]> sha512 = new HashMap<>();
 	private String baseDirectory;
 	private int TCPPort;
 	private ServerSocket socket;
@@ -55,6 +63,7 @@ public class ServerManagementTCP implements Runnable {
 		this.baseDirectory = baseDirectory;
 		this.TCPPort = TCPPort;
 		initFileList();
+		initSha512();
 		try {
 			socket = new ServerSocket(TCPPort);
 		} catch (SocketException e) {
@@ -123,6 +132,10 @@ public class ServerManagementTCP implements Runnable {
 						logger.writeTCP(addr + "LIST_REQUEST", LogLevel.Action);
 						sendListResponse(pd);
 						break;
+					case HASH_REQUEST:
+						logger.writeTCP(addr + "HASH_REQUEST", LogLevel.Action);
+						sendHashResponse(pd);
+						break;
 					default:
 						logger.writeTCP(addr + "Received grabbage", LogLevel.Action);
 						sendInternalError(pd);
@@ -158,6 +171,22 @@ public class ServerManagementTCP implements Runnable {
 		Arrays.sort(fileList);
 	}
 
+	/** Init sha512 map.
+	 */
+	 private void initSha512() {
+		for(String f: fileList) {
+			try {
+				MessageDigest md = MessageDigest.getInstance(HashAlgorithm.SHA512.getName()); 
+				sha512.put(f, md.digest(Files.readAllBytes(Paths.get(baseDirectory + f))));
+				md.reset();
+			} catch (NoSuchAlgorithmException e) {
+				logger.writeTCP("sha512 not supported", LogLevel.Error);
+			} catch (IOException e) {
+				logger.writeTCP("cannot read " + f, LogLevel.Warning);
+			}
+		}
+	}
+
 	/** Send an internal error message.
 	 * @param pd	ProtocolP2PPacketTCP to respond
 	 */
@@ -187,6 +216,46 @@ public class ServerManagementTCP implements Runnable {
 		}
 	}
 
+	/** Send hash response to hash request
+	 * @param pd	Request received
+	 */
+	private void sendHashResponse(ProtocolP2PPacketTCP pd) {
+		Payload p = pd.getPayload();
+		assert p instanceof HashRequest : "payload must be an instance of HashRequest";
+		if (!(p instanceof HashRequest)) {
+			sendInternalError(pd);
+		} else {
+			String filename = ((HashRequest)p).getFilename();
+			if (Arrays.binarySearch(fileList, filename) >= 0) {
+				Map<HashAlgorithm, byte[]> hashes = new HashMap<>();
+				for (HashAlgorithm h : ((HashRequest)p).getAlgoList()) {
+					switch (h) {
+						case SHA512:
+							hashes.put(h, sha512.get(filename));
+							break;
+						case MD5:
+						default:
+							hashes.put(h, new byte[0]);
+							break;
+					}
+				}
+				try {
+					pd.sendResponse((ProtocolP2PPacket)new ProtocolP2PPacketTCP((Payload)(new HashResponse(filename, hashes))));
+				} catch (Exception e) {
+					logger.writeTCP(e, LogLevel.Error);
+				}
+			} else {
+				// file not found
+				try {
+					pd.sendResponse((ProtocolP2PPacket)new ProtocolP2PPacketTCP(new Payload(RequestResponseCode.NOT_FOUND)));
+				} catch (Exception e) {
+					logger.writeTCP(e, LogLevel.Error);
+				}
+			}
+		}
+	}
+			
+
 	/** Send response to load request
 	 * @param pd	Request received
 	 */

src/serverP2P/ServerManagementUDP.java

@@ -7,6 +7,8 @@ import java.net.InetAddress;
 import java.net.SocketException;
 import java.nio.file.Paths;
 import java.nio.file.Files;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
 import protocolP2P.ProtocolP2PPacketUDP;
 import protocolP2P.ProtocolP2PPacket;
 import protocolP2P.RequestResponseCode;
@@ -29,7 +31,11 @@ import remoteException.EmptyFile;
 import java.util.Arrays;
 import tools.Logger;
 import tools.LogLevel;
-
+import java.util.HashMap;
+import java.util.Map;
+import protocolP2P.HashAlgorithm;
+import protocolP2P.HashRequest;
+import protocolP2P.HashResponse;
 
 /** Implementation of P2P-JAVA-PROJECT VERSION 1.0 protocol for UDP.
  * @author	Louis Royer
@@ -40,6 +46,7 @@ import tools.LogLevel;
 public class ServerManagementUDP implements Runnable {
 
 	private String[] fileList;
+	private Map<String, byte[]> sha512 = new HashMap<>();
 	private String baseDirectory;
 	private int UDPPort;
 	private DatagramSocket socket;
@@ -54,6 +61,7 @@ public class ServerManagementUDP implements Runnable {
 		this.baseDirectory = baseDirectory;
 		this.UDPPort = UDPPort;
 		initFileList();
+		initSha512();
 		try {
 			socket = new DatagramSocket(UDPPort);
 		} catch (SocketException e) {
@@ -134,6 +142,10 @@ public class ServerManagementUDP implements Runnable {
 							logger.writeUDP(e2, LogLevel.Error);
 						}
 						break;
+					case HASH_REQUEST:
+						logger.writeUDP("Received HASH_REQUEST", LogLevel.Action);
+						sendHashResponse(pd);
+						break;
 					default:
 						sendInternalError(pd);
 				}
@@ -165,7 +177,21 @@ public class ServerManagementUDP implements Runnable {
 		Arrays.sort(fileList);
 	}
 
-
+	/** Init sha512 map.
+	 */
+	 private void initSha512() {
+		for(String f: fileList) {
+			try {
+				MessageDigest md = MessageDigest.getInstance(HashAlgorithm.SHA512.getName()); 
+				sha512.put(f, md.digest(Files.readAllBytes(Paths.get(baseDirectory + f))));
+				md.reset();
+			} catch (NoSuchAlgorithmException e) {
+				logger.writeUDP("sha512 not supported", LogLevel.Error);
+			} catch (IOException e) {
+				logger.writeUDP("cannot read " + f, LogLevel.Warning);
+			}
+		}
+	}
 	
 	/** Send an internal error message.
 	 * @param pd	ProtocolP2PPacketUDP to respond
@@ -179,5 +205,44 @@ public class ServerManagementUDP implements Runnable {
 		}
 	}
 
+	/** Send hash response to hash request
+	 * @param pd	Request received
+	 */
+	private void sendHashResponse(ProtocolP2PPacketUDP pd) {
+		Payload p = pd.getPayload();
+		assert p instanceof HashRequest : "payload must be an instance of HashRequest";
+		if (!(p instanceof HashRequest)) {
+			sendInternalError(pd);
+		} else {
+			String filename = ((HashRequest)p).getFilename();
+			if (Arrays.binarySearch(fileList, filename) >= 0) {
+				Map<HashAlgorithm, byte[]> hashes = new HashMap<>();
+				for (HashAlgorithm h : ((HashRequest)p).getAlgoList()) {
+					switch (h) {
+						case SHA512:
+							hashes.put(h, sha512.get(filename));
+							break;
+						case MD5:
+						default:
+							hashes.put(h, new byte[0]);
+							break;
+					}
+				}
+				try {
+					pd.sendResponse((ProtocolP2PPacket)new ProtocolP2PPacketUDP((Payload)(new HashResponse(filename, hashes))));
+				} catch (Exception e) {
+					logger.writeUDP(e, LogLevel.Error);
+				}
+			} else {
+				// file not found
+				try {
+					pd.sendResponse((ProtocolP2PPacket)new ProtocolP2PPacketUDP(new Payload(RequestResponseCode.NOT_FOUND)));
+				} catch (Exception e) {
+					logger.writeUDP(e, LogLevel.Error);
+				}
+			}
+		}
+	}
+
 }
 

src/tools/BytesArrayTools.java

@@ -100,4 +100,20 @@ public class BytesArrayTools {
 		return size;
 	}
 
+	/** Remove trailing null bytes from string.
+	 * @param str	input string
+	 * @return	str without trailing null bytes
+	 */
+	public static String cleanStrings(String str) {
+		int i = 0;
+		int cpt = 0;
+		byte[] bArray = str.getBytes();
+		for (byte b : bArray) {
+			if (b != 0) {
+				cpt = i;
+			}
+			i++;
+		}
+		return new String(bArray, 0, cpt + 1);
+	}
 }

src/tools/Logger.java

@@ -98,6 +98,7 @@ public class Logger {
 	 */
 	public void writeTCP(Exception e, LogLevel logLevel) {
 		writeTCP(e.toString(), logLevel);
+		e.printStackTrace();
 	}
 
 	/** Appends log to filelog and print to stderr.
@@ -116,6 +117,7 @@ public class Logger {
 	 */
 	public void writeUDP(Exception e, LogLevel logLevel) {
 		writeUDP(e.toString(), logLevel);
+		e.printStackTrace();
 	}
 
 }