Implement full handshake and login over DMAP2.0

src/main/java/dslab/client/MessageClient.java

@@ -77,7 +77,9 @@ public class MessageClient implements IMessageClient, Runnable {
             String input = null;
             String message = null;
 
-            if (!(input = this.dmapIn.readLine()).startsWith("ok DMAP2.0"))
+            input = dmapIn.readLine();
+            logger.info("Received message from server: " + input);
+            if (!input.startsWith("ok DMAP2.0"))
                 shutdown();
 
             startSecure();
@@ -110,7 +112,9 @@ public class MessageClient implements IMessageClient, Runnable {
         String componentId;
         PublicKey serverPublicKey;
         this.dmapOut.println("startsecure");
+        logger.info("Sent command 'startsecure'");
         input = this.dmapIn.readLine();
+        logger.info("Server's response: " + input);
         if (input.startsWith("ok") && (input.split("\\s+").length == 2)) {
             // Get the component-id from the server
             componentId = input.split("\\s+")[1];
@@ -127,12 +131,14 @@ public class MessageClient implements IMessageClient, Runnable {
                 logger.info("Server's Public Key: " + serverPublicKey);
                 String clientChallenge = generateChallengeMessage(serverPublicKey);
                 // Send clientChallenge to server
+                logger.info("Send clientchallenge to Server: " + clientChallenge);
                 this.dmapOut.println(clientChallenge);
                 // Receive AES encrypted message saying "ok <client-challenge>"
                 String response = this.dmapIn.readLine();
                 // Compare received client challenge with generated client challenge
                 verifyChallenge(response);
                 // Answer with AES encrypted "ok" if matching and use AES cipher for subsequent communication
+                logger.info("Send ciphered 'ok' to Server: " + getAesCiphertext("ok"));
                 this.dmapOut.println(getAesCiphertext("ok"));
             } catch (NoSuchAlgorithmException | InvalidKeySpecException | IllegalBlockSizeException | BadPaddingException | FailedVerificationException e) {
                 logger.severe(e.getMessage());
@@ -146,6 +152,7 @@ public class MessageClient implements IMessageClient, Runnable {
 
     /**
      * Takes a plaintext message, encrypts and encodes it and returns the encoded ciphertext ready for sending.
+     *
      * @param message Plaintext message
      * @return B64 encoded and AES encrypted ciphertext
      */
@@ -156,6 +163,7 @@ public class MessageClient implements IMessageClient, Runnable {
 
     /**
      * Takes an AES encrypted message, decrypts and decodes it and returns the plaintext.
+     *
      * @param message B64 encoded and AES encrypted message
      * @return B64 decoded and AES decrypted plaintext
      */
@@ -178,11 +186,12 @@ public class MessageClient implements IMessageClient, Runnable {
         // Decode <client-challenge>
         if (plainText.split("\\s+").length != 2)
             shutdown();
-        String clientChallenge = new String(Base64.getDecoder().decode(plainText.split("\\s+")[1]));
+        byte[] clientChallenge = Base64.getDecoder().decode(plainText.split("\\s+")[1]);
         // Compare received challenge with sent
 
-        if (!clientChallenge.equals(new String(this.challenge)))
+        if (!Arrays.equals(clientChallenge, this.challenge))
-            throw new FailedVerificationException("Server's clientChallenge " + clientChallenge + " does not match sent clientChallenge " + new String(this.challenge));
+            throw new FailedVerificationException("Server's clientChallenge " + new String(clientChallenge) +
+                    " does not match sent clientChallenge " + new String(this.challenge));
     }
 
     private SecretKeySpec generateSecretKey() {
@@ -205,7 +214,7 @@ public class MessageClient implements IMessageClient, Runnable {
         return new IvParameterSpec(iv);
     }
 
-    private void setAesCipher(SecretKeySpec secretKey, IvParameterSpec iv) {
+    private void setAesCiphers(SecretKeySpec secretKey, IvParameterSpec iv) {
         try {
             this.aesEncryptCipher = Cipher.getInstance("AES/CTR/NoPadding");
             this.aesDecryptCipher = Cipher.getInstance("AES/CTR/NoPadding");
@@ -240,13 +249,13 @@ public class MessageClient implements IMessageClient, Runnable {
         assert secretKeySpec != null;
         IvParameterSpec iv = generateIv();
         // Save AES cipher for subsequent communication
-        setAesCipher(secretKeySpec, iv);
+        setAesCiphers(secretKeySpec, iv);
         // Encode parameters to base64
         String clearTextChallengeEncoded = Base64.getEncoder().encodeToString(clearTextChallenge);
         String secretKeyEncoded = Base64.getEncoder().encodeToString(secretKeySpec.getEncoded());
         String ivEncoded = Base64.getEncoder().encodeToString(iv.getIV());
         // Concatenate command and parameters (challenge, secretKey and IV)
-        String concatenated = "ok" + clearTextChallengeEncoded + secretKeyEncoded + ivEncoded;
+        String concatenated = "ok " + clearTextChallengeEncoded + " " + secretKeyEncoded + " " + ivEncoded;
         // Encrypt "<base64Encoded>"
         Cipher cipher;
         byte[] cipherTextChallenge;

src/main/java/dslab/mailbox/DMAPConnection.java

@@ -4,15 +4,33 @@ import dslab.Email;
 import dslab.Message;
 import dslab.exception.MessageNotFoundException;
 
+import javax.crypto.BadPaddingException;
+import javax.crypto.Cipher;
+import javax.crypto.IllegalBlockSizeException;
+import javax.crypto.NoSuchPaddingException;
+import javax.crypto.spec.IvParameterSpec;
+import javax.crypto.spec.SecretKeySpec;
 import java.io.*;
 import java.net.Socket;
 import java.net.SocketException;
+import java.nio.charset.Charset;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.security.*;
+import java.security.spec.InvalidKeySpecException;
+import java.security.spec.PKCS8EncodedKeySpec;
+import java.security.spec.X509EncodedKeySpec;
+import java.util.Arrays;
+import java.util.Base64;
 import java.util.LinkedList;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.logging.Level;
 import java.util.logging.Logger;
 
 public class DMAPConnection implements Runnable {
     Logger logger = Logger.getLogger(DMAPConnection.class.getName());
+    private final String componentId;
     private final Socket socket;
     private PrintWriter out;
     private BufferedReader in;
@@ -20,10 +38,15 @@ public class DMAPConnection implements Runnable {
     private final ConcurrentHashMap<Email, LinkedList<Message>> storage;
     private final ConcurrentHashMap<String, String> userStorage;
 
-    public DMAPConnection(Socket connection, ConcurrentHashMap<Email, LinkedList<Message>> storage, ConcurrentHashMap<String, String> userStorage) {
+    private Cipher aesEncryptCipher;
+    private Cipher aesDecryptCipher;
+
+    public DMAPConnection(Socket connection, ConcurrentHashMap<Email, LinkedList<Message>> storage, ConcurrentHashMap<String, String> userStorage, String componentId) {
+        this.componentId = componentId;
         this.socket = connection;
         this.storage = storage;
         this.userStorage = userStorage;
+        logger.setLevel(Level.ALL);
     }
 
     @Override
@@ -32,8 +55,9 @@ public class DMAPConnection implements Runnable {
         try {
             this.out = new PrintWriter(socket.getOutputStream(), true);
             this.in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
-            out.println("ok DMAP");
+            out.println("ok DMAP2.0");
-            loginLoop();
+            startSecure();
+            login();
 
             String userInput;
             while (!Thread.currentThread().isInterrupted() && (userInput = in.readLine()) != null) {
@@ -42,8 +66,7 @@ public class DMAPConnection implements Runnable {
                     shutdown();
                 } else if ("logout".equals(userInput)) {
                     out.println("ok");
-                    currentUser = null;
+                    shutdown();
-                    loginLoop();
                 } else if ("list".equals(userInput)) {
                     listMessages();
                 } else if ("delete".equals(userInput.split("\\s+")[0])) {
@@ -81,14 +104,135 @@ public class DMAPConnection implements Runnable {
         }
     }
 
-    private void loginLoop() {
+    /**
+     * Handles the startsecure command issued by the MessageClient.
+     */
+    private void startSecure() {
+        String userInput;
+
+        try {
+            userInput = in.readLine();  // Should always be "startsecure"
+            // Send componentId
+            out.println("ok " + componentId);
+            // Receive client challenge, secret key and iv
+            userInput = in.readLine();
+            logger.info("Received clientchallenge from Client: " + userInput);
+            String[] rsaPlaintext = getRsaPlaintext(userInput).split("\\s+");
+            logger.info("Plaintext of clientchallenge: " + Arrays.toString(rsaPlaintext));
+            // Initialize AES cipher(s) (encryption and decryption)
+            setAesCiphers(rsaPlaintext[2], rsaPlaintext[3]);
+            // Encrypt client challenge with AES and send to MessageClient
+            out.println(encryptClientChallenge(rsaPlaintext[1]));
+            // Decrypt AES encrypted "ok" from MessageClient
+            userInput = getAesPlaintext(in.readLine());
+            if (!userInput.equals("ok")) {
+                logger.severe("Received " + userInput + "from MessageClient. Did not match 'ok'");
+                shutdown();
+            }
+        } catch (InterruptedIOException ioe) {
+            logger.info("Received interrupt from parent. Shutting down...");
+            shutdown();
+        } catch (SocketException e) {
+            logger.finer("Received interrupt. Exiting " + this.toString());
+            shutdown();
+        } catch (IOException e) {
+            logger.severe("Failed to get IO-Stream");
+            e.printStackTrace();
+            shutdown();
+        } catch (NoSuchAlgorithmException | InvalidKeyException | NoSuchPaddingException | BadPaddingException |
+                InvalidKeySpecException | IllegalBlockSizeException | InvalidAlgorithmParameterException e) {
+            logger.severe("Error during encryption/decryption. Aborting...");
+            e.printStackTrace();
+            shutdown();
+        }
+    }
+
+    /**
+     * Takes a plaintext message, encrypts and encodes it and returns the encoded ciphertext ready for sending.
+     *
+     * @param message Plaintext message
+     * @return B64 encoded and AES encrypted ciphertext
+     */
+    private String getAesCiphertext(String message) throws IllegalBlockSizeException, BadPaddingException {
+        byte[] cipherText = aesEncryptCipher.doFinal(message.getBytes(StandardCharsets.UTF_8));
+        return Base64.getEncoder().encodeToString(cipherText);
+    }
+
+    /**
+     * Takes an AES encrypted message, decrypts and decodes it and returns the plaintext.
+     *
+     * @param message B64 encoded and AES encrypted message
+     * @return B64 decoded and AES decrypted plaintext
+     */
+    private String getAesPlaintext(String message) throws BadPaddingException, IllegalBlockSizeException {
+        byte[] cipherText = Base64.getDecoder().decode(message.getBytes(StandardCharsets.UTF_8));
+        return new String(aesDecryptCipher.doFinal(cipherText));
+    }
+
+    /**
+     * Encrypts the client challenge with the AES cipher.
+     *
+     * @param clientChallenge Base64 encoded client challenge. Supplied by the MessageClient.
+     * @return Return the AES encrypted and encoded clientChallenge ready for sending.
+     */
+    private String encryptClientChallenge(String clientChallenge) throws BadPaddingException, IllegalBlockSizeException {
+        String completeClientChallenge = "ok " + clientChallenge;
+        return Base64.getEncoder().encodeToString(aesEncryptCipher.doFinal(completeClientChallenge.getBytes(StandardCharsets.UTF_8)));
+    }
+
+    /**
+     * Takes an RSA encrypted message and constructs AES ciphers.
+     *
+     * @param message Has the form "ok <client-challenge> <secret-key> <iv>".
+     * @return Returns the decrypted and (partially) decoded challenge
+     */
+    private String getRsaPlaintext(String message) throws IOException, NoSuchAlgorithmException, InvalidKeySpecException,
+            NoSuchPaddingException, InvalidKeyException, BadPaddingException, IllegalBlockSizeException {
+        byte[] rsaEncrypted = Base64.getDecoder().decode(message);
+        byte[] keyBytes = Files.readAllBytes(Paths.get("keys", "server", componentId + ".der"));
+        logger.info("Read bytes from path " + Paths.get("keys", "server", componentId + ".der") + ": " + Arrays.toString(keyBytes));
+        // Create X509 spec object from key
+        // TODO Use readKey function provided by LVA-Team
+        PKCS8EncodedKeySpec spec = new PKCS8EncodedKeySpec(keyBytes);
+        // Create generator for RSA scheme
+        KeyFactory kf = KeyFactory.getInstance("RSA");
+        // Make generator generate private key from X509 spec
+        PrivateKey serverPrivateKey = kf.generatePrivate(spec);
+        Cipher cipher;
+        cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
+        cipher.init(Cipher.DECRYPT_MODE, serverPrivateKey);
+        byte[] cipherTextChallenge = cipher.doFinal(rsaEncrypted);
+        return new String(cipherTextChallenge);
+    }
+
+    /**
+     * Sets global AES ciphers for encryption and decryption.
+     *
+     * @param secretKey Base64 encoded secret key. Supplied by the MessageClient.
+     * @param iv        Base64 encoded IV. Supplied by the MessageClient.
+     */
+    private void setAesCiphers(String secretKey, String iv) throws InvalidAlgorithmParameterException,
+            InvalidKeyException, NoSuchPaddingException, NoSuchAlgorithmException {
+        SecretKeySpec decodedSecretKey = new SecretKeySpec(Base64.getDecoder().decode(secretKey), "AES");
+        IvParameterSpec decodedIv = new IvParameterSpec(Base64.getDecoder().decode(iv));
+        this.aesEncryptCipher = Cipher.getInstance("AES/CTR/NoPadding");
+        this.aesDecryptCipher = Cipher.getInstance("AES/CTR/NoPadding");
+
+        this.aesEncryptCipher.init(Cipher.ENCRYPT_MODE, decodedSecretKey, decodedIv);
+        this.aesDecryptCipher.init(Cipher.DECRYPT_MODE, decodedSecretKey, decodedIv);
+    }
+
+    /**
+     * Handles the login command issued by the MessageClient which is already encrypted.
+     */
+    private void login() {
         String userInput;
 
         try {
             while (!Thread.currentThread().isInterrupted()) {
-                userInput = in.readLine();
+                userInput = getAesPlaintext(in.readLine());
                 if ("quit".equals(userInput.split("\\s+")[0])) {
-                    out.println("ok bye");
+                    out.println(getAesCiphertext("ok bye"));
                     shutdown();
                 } else if ("login".equals(userInput.split("\\s+")[0])) {
                     String[] args = userInput.split("\\s+");
@@ -103,7 +247,7 @@ public class DMAPConnection implements Runnable {
                                     // Set current user if login successful
                                     currentUser = email;
                                     logger.info("User successfully logged in: " + currentUser.toString());
-                                    out.println("ok");
+                                    out.println(getAesCiphertext("ok"));
                                     return;
                                 }
                             }
@@ -127,6 +271,10 @@ public class DMAPConnection implements Runnable {
             logger.severe("Failed to get IO-Stream");
             e.printStackTrace();
             shutdown();
+        } catch (BadPaddingException | IllegalBlockSizeException e) {
+            logger.severe("Error while encrypting/decrypting. Aborting...");
+            e.printStackTrace();
+            shutdown();
         }
     }
 
@@ -159,7 +307,7 @@ public class DMAPConnection implements Runnable {
         }
     }
 
-    public void deleteMessage (String id) throws MessageNotFoundException {
+    public void deleteMessage(String id) throws MessageNotFoundException {
         int i;
         try {
             i = Integer.parseInt(id);

src/main/java/dslab/mailbox/DMAPListener.java

@@ -14,9 +14,11 @@ import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.TimeUnit;
+import java.util.logging.Level;
 import java.util.logging.Logger;
 
 public class DMAPListener extends Thread {
+    private final String componentId;
     private final ServerSocket serverSocket;
     private final Logger logger = Logger.getLogger(DMAPListener.class.getName());
     private final ConcurrentHashMap<Email, LinkedList<Message>> storage;
@@ -24,10 +26,12 @@ public class DMAPListener extends Thread {
     private final ArrayList<DMAPConnection> clients = new ArrayList<>();
     private final ExecutorService executorService = Executors.newCachedThreadPool();
 
-    public DMAPListener(ServerSocket serverSocket, ConcurrentHashMap<Email, LinkedList<Message>> storage, ConcurrentHashMap<String, String> userStorage) {
+    public DMAPListener(ServerSocket serverSocket, ConcurrentHashMap<Email, LinkedList<Message>> storage, ConcurrentHashMap<String, String> userStorage, String componentId) {
+        this.componentId = componentId;
         this.serverSocket = serverSocket;
         this.storage = storage;
         this.userStorage = userStorage;
+        logger.setLevel(Level.ALL);
     }
 
     @Override
@@ -37,7 +41,7 @@ public class DMAPListener extends Thread {
             try {
                 Socket s = serverSocket.accept();
                 logger.fine("Processing incoming socket " + s.toString());
-                DMAPConnection dmapConnection = new DMAPConnection(s, storage, userStorage);
+                DMAPConnection dmapConnection = new DMAPConnection(s, storage, userStorage, componentId);
                 clients.add(dmapConnection);
                 executorService.submit(dmapConnection);
             } catch (InterruptedIOException | SocketException e) {

src/main/java/dslab/mailbox/MailboxServer.java

@@ -6,6 +6,7 @@ import java.io.PrintStream;
 import java.net.ServerSocket;
 import java.util.LinkedList;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.logging.Level;
 import java.util.logging.Logger;
 
 import at.ac.tuwien.dsg.orvell.Shell;
@@ -18,6 +19,7 @@ import dslab.util.Config;
 
 public class MailboxServer implements IMailboxServer, Runnable {
     private static final Logger logger = Logger.getLogger(MailboxServer.class.getName());
+    private final String componentId;
     private final String domain;
     private ServerSocket dmtpServerSocket;
     private ServerSocket dmapServerSocket;
@@ -42,6 +44,7 @@ public class MailboxServer implements IMailboxServer, Runnable {
      */
     public MailboxServer(String componentId, Config config, InputStream in, PrintStream out) {
         this.domain = config.getString("domain");
+        this.componentId = componentId;
         Config userConfig = new Config(config.getString("users.config"));
 
         // Load users from config into userStorage for authentication
@@ -61,6 +64,7 @@ public class MailboxServer implements IMailboxServer, Runnable {
         this.shell.setPrompt("Mailboxserver> ");
         this.dmtpServerPort = config.getInt("dmtp.tcp.port");
         this.dmapServerPort = config.getInt("dmap.tcp.port");
+        logger.setLevel(Level.ALL);
     }
 
     @Override
@@ -76,7 +80,7 @@ public class MailboxServer implements IMailboxServer, Runnable {
         }
         this.dmtpListener = new DMTPListener(this.dmtpServerSocket, this.messageStorage, this.userStorage, this.domain);
         this.dmtpListener.start();
-        this.dmapListener = new DMAPListener(this.dmapServerSocket, this.messageStorage, this.userStorage);
+        this.dmapListener = new DMAPListener(this.dmapServerSocket, this.messageStorage, this.userStorage, this.componentId);
         this.dmapListener.start();
         this.shell.run();
     }