1 files changed, 141 insertions, 0 deletions
diff --git a/plugins/org.eclipse.net4j.util/src/org/eclipse/net4j/util/security/ChallengeNegotiator.java b/plugins/org.eclipse.net4j.util/src/org/eclipse/net4j/util/security/ChallengeNegotiator.java
new file mode 100644
index 0000000000..4054dfa8d1
--- /dev/null
+++ b/plugins/org.eclipse.net4j.util/src/org/eclipse/net4j/util/security/ChallengeNegotiator.java
@@ -0,0 +1,141 @@
+/***************************************************************************
+ * Copyright (c) 2004 - 2008 Eike Stepper, Germany.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ * 
+ * Contributors:
+ *    Eike Stepper - initial API and implementation
+ **************************************************************************/
+package org.eclipse.net4j.util.security;
+
+import java.nio.ByteBuffer;
+import java.util.Arrays;
+
+/**
+ * @author Eike Stepper
+ */
+public class ChallengeNegotiator extends ChallengeResponseNegotiator
+{
+  public static final int DEFAULT_TOKEN_LENGTH = 1024;
+
+  private int tokenLength = DEFAULT_TOKEN_LENGTH;
+
+  private IRandomizer randomizer;
+
+  private IUserManager userManager;
+
+  public ChallengeNegotiator()
+  {
+    super(true);
+  }
+
+  public int getTokenLength()
+  {
+    return tokenLength;
+  }
+
+  public void setTokenLength(int tokenLength)
+  {
+    this.tokenLength = tokenLength;
+  }
+
+  public IRandomizer getRandomizer()
+  {
+    return randomizer;
+  }
+
+  public void setRandomizer(IRandomizer randomizer)
+  {
+    this.randomizer = randomizer;
+  }
+
+  public IUserManager getUserManager()
+  {
+    return userManager;
+  }
+
+  public void setUserManager(IUserManager userManager)
+  {
+    this.userManager = userManager;
+  }
+
+  @Override
+  protected void doBeforeActivate() throws Exception
+  {
+    super.doBeforeActivate();
+    if (tokenLength <= 0)
+    {
+      throw new IllegalStateException("tokenLength must be positive");
+    }
+
+    if (randomizer == null)
+    {
+      throw new IllegalStateException("randomizer == null");
+    }
+
+    if (userManager == null)
+    {
+      throw new IllegalStateException("userManager == null");
+    }
+  }
+
+  protected byte[] createRandomToken()
+  {
+    byte[] token = new byte[tokenLength];
+    randomizer.nextBytes(token);
+    return token;
+  }
+
+  protected byte[] encryptToken(String userID, byte[] token) throws SecurityException
+  {
+    return userManager.encrypt(userID, token, getAlgorithmName());
+  }
+
+  @Override
+  protected void createChallenge(INegotiationContext context, ByteBuffer challenge)
+  {
+    // Create and remember a random token
+    byte[] randomToken = createRandomToken();
+    context.setInfo(randomToken);
+
+    // Set the token into challenge
+    challenge.putInt(randomToken.length);
+    challenge.put(randomToken);
+  }
+
+  @Override
+  protected void handleChallenge(INegotiationContext context, ByteBuffer challenge, ByteBuffer response)
+  {
+    throw new UnsupportedOperationException();
+  }
+
+  @Override
+  protected boolean handleResponse(INegotiationContext context, ByteBuffer response)
+  {
+    // Get remembered random token
+    byte[] randomToken = (byte[])context.getInfo();
+
+    // Get userID from response
+    int size = response.getInt();
+    byte[] userIDBytes = new byte[size];
+    response.get(userIDBytes);
+    String userID = new String(userIDBytes);
+
+    // Get crypted token from response
+    size = response.getInt();
+    byte[] responseToken = new byte[size];
+    response.get(responseToken);
+
+    // Encrypt the remembered token and compare to crypted token from response
+    byte[] cryptedToken = encryptToken(userID, randomToken);
+    boolean success = Arrays.equals(responseToken, cryptedToken);
+    if (success)
+    {
+      context.setUserID(userID);
+    }
+
+    return success;
+  }
+}