Enable RSA.

src/org/apollo/game/GameService.java

@@ -15,6 +15,7 @@ import org.apollo.game.model.World;
 import org.apollo.game.model.World.RegistrationStatus;
 import org.apollo.game.sync.ClientSynchronizer;
 import org.apollo.io.EventHandlerChainParser;
+import org.apollo.io.RsaKeyParser;
 import org.apollo.login.LoginService;
 import org.apollo.net.session.GameSession;
 import org.apollo.util.NamedThreadFactory;
@@ -117,6 +118,14 @@ public final class GameService extends Service {
 		} finally {
 			is.close();
 		}
+
+		is = new FileInputStream("data/rsa.xml");
+		try {
+			RsaKeyParser parser = new RsaKeyParser(is);
+			parser.parse();
+		} finally {
+			is.close();
+		}
 	}
 
 	/**

src/org/apollo/io/RsaKeyParser.java

@@ -0,0 +1,66 @@
+package org.apollo.io;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.math.BigInteger;
+
+import org.apollo.net.NetworkConstants;
+import org.apollo.util.xml.XmlNode;
+import org.apollo.util.xml.XmlParser;
+import org.xml.sax.SAXException;
+
+/**
+ * A class that parses the {@code rsa.xml} file.
+ * 
+ * @author Major
+ */
+public class RsaKeyParser {
+
+	/**
+	 * The source {@link InputStream}.
+	 */
+	private final InputStream is;
+
+	/**
+	 * The {@link XmlParser} instance.
+	 */
+	private final XmlParser parser;
+
+	/**
+	 * Creates the RSA specification parser.
+	 * 
+	 * @param is The source {@link InputStream}.
+	 * @throws SAXException If a SAX error occurs.
+	 */
+	public RsaKeyParser(InputStream is) throws SAXException {
+		parser = new XmlParser();
+		this.is = is;
+	}
+
+	/**
+	 * Parses the {@code rsa.xml} file.
+	 * 
+	 * @throws SAXException If a SAX error occurs.
+	 * @throws IOException
+	 */
+	public void parse() throws SAXException, IOException {
+		XmlNode rootNode = parser.parse(is);
+		if (!rootNode.getName().equals("rsa")) {
+			throw new IOException("root node name is not 'rsa'");
+		}
+
+		XmlNode modulusNode = rootNode.getChild("modulus");
+		if (modulusNode == null) {
+			throw new IOException("no node named 'modulus' beneath root node");
+		}
+
+		XmlNode exponentNode = rootNode.getChild("private-exponent");
+		if (exponentNode == null) {
+			throw new IOException("no node named 'private-exponent' beneath root node");
+		}
+
+		NetworkConstants.RSA_MODULUS = new BigInteger(modulusNode.getValue());
+		NetworkConstants.RSA_EXPONENT = new BigInteger(exponentNode.getValue());
+	}
+
+}

src/org/apollo/net/NetworkConstants.java

@@ -1,5 +1,7 @@
 package org.apollo.net;
 
+import java.math.BigInteger;
+
 /**
  * Holds various network-related constants such as port numbers.
  * 
@@ -22,6 +24,16 @@ public final class NetworkConstants {
 	 */
 	public static final int JAGGRAB_PORT = 43595;
 
+	/**
+	 * The exponent used when decrypting the RSA block.
+	 */
+	public static BigInteger RSA_EXPONENT;
+
+	/**
+	 * The modulus used when decrypting the RSA block.
+	 */
+	public static BigInteger RSA_MODULUS;
+
 	/**
 	 * The service port.
 	 */
@@ -39,4 +51,4 @@ public final class NetworkConstants {
 
 	}
 
-}
+}

src/org/apollo/net/codec/login/LoginDecoder.java

@@ -1,10 +1,12 @@
 package org.apollo.net.codec.login;
 
+import java.math.BigInteger;
 import java.security.SecureRandom;
 
 import net.burtleburtle.bob.rand.IsaacRandom;
 
 import org.apollo.fs.FileSystemConstants;
+import org.apollo.net.NetworkConstants;
 import org.apollo.security.IsaacRandomPair;
 import org.apollo.security.PlayerCredentials;
 import org.apollo.util.ChannelBufferUtil;
@@ -64,7 +66,7 @@ public final class LoginDecoder extends StatefulFrameDecoder<LoginDecoderState>
 		case LOGIN_PAYLOAD:
 			return decodePayload(ctx, channel, buffer);
 		default:
-			throw new Exception("Invalid login decoder state");
+			throw new IllegalArgumentException("Invalid login decoder state");
 		}
 	}
 
@@ -156,6 +158,11 @@ public final class LoginDecoder extends StatefulFrameDecoder<LoginDecoderState>
 
 			ChannelBuffer securePayload = payload.readBytes(securePayloadLength);
 
+			BigInteger bigInteger = new BigInteger(securePayload.array());
+			bigInteger = bigInteger.modPow(NetworkConstants.RSA_EXPONENT, NetworkConstants.RSA_MODULUS);
+
+			securePayload = ChannelBuffers.wrappedBuffer(bigInteger.toByteArray());
+
 			int secureId = securePayload.readUnsignedByte();
 			if (secureId != 10) {
 				throw new Exception("Invalid secure payload id");
@@ -173,7 +180,7 @@ public final class LoginDecoder extends StatefulFrameDecoder<LoginDecoderState>
 			String password = ChannelBufferUtil.readString(securePayload);
 
 			if (username.length() > 12 || password.length() > 20) {
-				throw new Exception("Username or password too long");
+				throw new Exception("Username or password too long.");
 			}
 
 			int[] seed = new int[4];
@@ -196,11 +203,10 @@ public final class LoginDecoder extends StatefulFrameDecoder<LoginDecoderState>
 
 			if (buffer.readable()) {
 				return new Object[] { req, buffer.readBytes(buffer.readableBytes()) };
-			} else {
-				return req;
 			}
+			return req;
 		}
 		return null;
 	}
 
-}
+}