Merged with released L2J-Unity files.

trunk/java/com/l2jmobius/commons/util/crypt/ScrambledKeyPair.java

@@ -0,0 +1,75 @@
+/*
+ * This file is part of the L2J Mobius project.
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.l2jmobius.commons.util.crypt;
+
+import java.math.BigInteger;
+import java.security.KeyPair;
+import java.security.interfaces.RSAPublicKey;
+import java.util.logging.Logger;
+
+/**
+ *
+ */
+public class ScrambledKeyPair
+{
+	private static Logger _log = Logger.getLogger(ScrambledKeyPair.class.getName());
+	public KeyPair _pair;
+	public byte[] _scrambledModulus;
+	
+	public ScrambledKeyPair(KeyPair pPair)
+	{
+		_pair = pPair;
+		_scrambledModulus = scrambleModulus(((RSAPublicKey) _pair.getPublic()).getModulus());
+	}
+	
+	private byte[] scrambleModulus(BigInteger modulus)
+	{
+		byte[] scrambledMod = modulus.toByteArray();
+		
+		if ((scrambledMod.length == 0x81) && (scrambledMod[0] == 0x00))
+		{
+			final byte[] temp = new byte[0x80];
+			System.arraycopy(scrambledMod, 1, temp, 0, 0x80);
+			scrambledMod = temp;
+		}
+		// step 1 : 0x4d-0x50 <-> 0x00-0x04
+		for (int i = 0; i < 4; i++)
+		{
+			final byte temp = scrambledMod[0x00 + i];
+			scrambledMod[0x00 + i] = scrambledMod[0x4d + i];
+			scrambledMod[0x4d + i] = temp;
+		}
+		// step 2 : xor first 0x40 bytes with last 0x40 bytes
+		for (int i = 0; i < 0x40; i++)
+		{
+			scrambledMod[i] = (byte) (scrambledMod[i] ^ scrambledMod[0x40 + i]);
+		}
+		// step 3 : xor bytes 0x0d-0x10 with bytes 0x34-0x38
+		for (int i = 0; i < 4; i++)
+		{
+			scrambledMod[0x0d + i] = (byte) (scrambledMod[0x0d + i] ^ scrambledMod[0x34 + i]);
+		}
+		// step 4 : xor last 0x40 bytes with first 0x40 bytes
+		for (int i = 0; i < 0x40; i++)
+		{
+			scrambledMod[0x40 + i] = (byte) (scrambledMod[0x40 + i] ^ scrambledMod[i]);
+		}
+		_log.finer("Modulus was scrambled");
+		
+		return scrambledMod;
+	}
+}