Minor cleanup - pom and encryption package

src/main/java/net/encryption/MapleCustomEncryption.java

@@ -0,0 +1,108 @@
+/*
+	This file is part of the OdinMS Maple Story Server
+    Copyright (C) 2008 Patrick Huy <patrick.huy@frz.cc>
+		       Matthias Butz <matze@odinms.de>
+		       Jan Christian Meyer <vimes@odinms.de>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Affero General Public License as
+    published by the Free Software Foundation version 3 as published by
+    the Free Software Foundation. You may not use, modify or distribute
+    this program under any other version of the GNU Affero General Public
+    License.
+
+    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 Affero General Public License for more details.
+
+    You should have received a copy of the GNU Affero General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+package net.encryption;
+
+public class MapleCustomEncryption {
+    private static byte rollLeft(byte in, int count) {
+        int tmp = (int) in & 0xFF;
+        tmp = tmp << (count % 8);
+        return (byte) ((tmp & 0xFF) | (tmp >> 8));
+    }
+
+    private static byte rollRight(byte in, int count) {
+        int tmp = (int) in & 0xFF;
+        tmp = (tmp << 8) >>> (count % 8);
+
+        return (byte) ((tmp & 0xFF) | (tmp >>> 8));
+    }
+
+    public static byte[] encryptData(byte[] data) {
+        for (int j = 0; j < 6; j++) {
+            byte remember = 0;
+            byte dataLength = (byte) (data.length & 0xFF);
+            if (j % 2 == 0) {
+                for (int i = 0; i < data.length; i++) {
+                    byte cur = data[i];
+                    cur = rollLeft(cur, 3);
+                    cur += dataLength;
+                    cur ^= remember;
+                    remember = cur;
+                    cur = rollRight(cur, (int) dataLength & 0xFF);
+                    cur = ((byte) ((~cur) & 0xFF));
+                    cur += 0x48;
+                    dataLength--;
+                    data[i] = cur;
+                }
+            } else {
+                for (int i = data.length - 1; i >= 0; i--) {
+                    byte cur = data[i];
+                    cur = rollLeft(cur, 4);
+                    cur += dataLength;
+                    cur ^= remember;
+                    remember = cur;
+                    cur ^= 0x13;
+                    cur = rollRight(cur, 3);
+                    dataLength--;
+                    data[i] = cur;
+                }
+            }
+        }
+        return data;
+    }
+
+    public static byte[] decryptData(byte[] data) {
+        for (int j = 1; j <= 6; j++) {
+            byte remember = 0;
+            byte dataLength = (byte) (data.length & 0xFF);
+            byte nextRemember;
+            if (j % 2 == 0) {
+                for (int i = 0; i < data.length; i++) {
+                    byte cur = data[i];
+                    cur -= 0x48;
+                    cur = ((byte) ((~cur) & 0xFF));
+                    cur = rollLeft(cur, (int) dataLength & 0xFF);
+                    nextRemember = cur;
+                    cur ^= remember;
+                    remember = nextRemember;
+                    cur -= dataLength;
+                    cur = rollRight(cur, 3);
+                    data[i] = cur;
+                    dataLength--;
+                }
+            } else {
+                for (int i = data.length - 1; i >= 0; i--) {
+                    byte cur = data[i];
+                    cur = rollLeft(cur, 3);
+                    cur ^= 0x13;
+                    nextRemember = cur;
+                    cur ^= remember;
+                    remember = nextRemember;
+                    cur -= dataLength;
+                    cur = rollRight(cur, 4);
+                    data[i] = cur;
+                    dataLength--;
+                }
+            }
+        }
+        return data;
+    }
+}