Fix client lacking encryption support

lib/consts.dart

@@ -1,3 +1,3 @@
 class Constants {
-  static const VERSION = "1.3.010625+0228";
+  static const VERSION = "1.3.010625+1127";
 }

lib/packets/packets.dart

@@ -38,6 +38,11 @@ enum EncryptionType {
   }
 }
 
+class PacketsConsts {
+  /// Version of the packets system. Bumped when there is a major change to protocol
+  static const VERSION = 2;
+}
+
 class PacketServer {
   static ServerSocket? socket;
   static bool shouldRestart = true;
@@ -46,9 +51,6 @@ class PacketServer {
   static String PSK = "";
   static String TEA_SALT = "Harbinger 01/05/2025 @ 03:59:17 AM";
 
-  /// Version of the packets system. Bumped when there is a major change to protocol
-  static const VERSION = 2;
-
   /// Packet Data Format:
   ///
   /// 4 bytes (int)  - Version
@@ -163,7 +165,7 @@ class PacketServer {
 
             // NOTE: Added a length indicator because SocketServer is apparently... really really dumb in its impl, and has no way to know when all data has been received, so no special event. We just have to check for it based on this initial value.
             layer.clear();
-            layer.writeInt(VERSION);
+            layer.writeInt(PacketsConsts.VERSION);
             layer.writeLong(nbtData.lengthInBytes + layer.currentPosition + 8);
             layer.writeBytes(nbtData);
 
@@ -199,6 +201,11 @@ class PacketClient {
   String lastIP = "";
   int port = 25306;
   int packetSequence = 0;
+  EncryptionType encryptionType = EncryptionType.NONE;
+  Uint8List aesKey = Uint8List(0);
+
+  /// Used for xtea encryption
+  String PSK = "";
 
   PacketClient();
 
@@ -251,7 +258,22 @@ class PacketClient {
 
     while (!success) {
       layer.clear();
+      layer.writeInt(PacketsConsts.VERSION);
       layer.writeLong(packetSequence);
+      layer.writeByte(encryptionType.value);
+
+      if (encryptionType == EncryptionType.AES) {
+        AESCipher aes = AESCipher.useKey(aesKey);
+        AESData encData = await aes.encrypt(nbtData);
+        layer.writeInt(encData.iv.length);
+        layer.writeBytes(encData.iv);
+
+        nbtData = Uint8List.fromList(encData.data);
+      } else if (encryptionType == EncryptionType.XTEA) {
+        XTEA xtea = XTEA(PSK);
+        nbtData = Uint8List.fromList(await xtea.encipher(nbtData.toList()));
+      }
+
       layer.writeLong(nbtData.lengthInBytes);
       layer.writeBytes(nbtData);
       var tmpBytes = layer.bytes;
@@ -281,6 +303,14 @@ class PacketClient {
         reply.readLong(); // This is unused outside of the sanity check above.
         int sequence = reply.readLong();
         int successReceipt = reply.readByte();
+        EncryptionType encType = EncryptionType.valueOf(layer.readByte());
+        List<int> encIV = [];
+
+        if (encType == EncryptionType.AES) {
+          int ivLen = layer.readInt();
+          encIV = layer.readBytes(ivLen);
+        }
+
         int numBytes = reply.readLong();
         List<int> pktBytes = reply.readBytes(numBytes);
 
@@ -288,6 +318,15 @@ class PacketClient {
           success = true;
 
         if (success) {
+          if (encType == EncryptionType.AES) {
+            AESCipher aes = AESCipher.useKey(aesKey);
+            AESData encData = AESData(iv: encIV, data: pktBytes);
+            pktBytes = (await aes.decrypt(encData)).toList();
+          } else if (encType == EncryptionType.XTEA) {
+            XTEA xtea = XTEA(PSK);
+            pktBytes = await xtea.decipher(pktBytes);
+          }
+
           NBTTag = await NbtIo.readFromStream(Uint8List.fromList(pktBytes));
         }
 

pubspec.yaml

@@ -1,6 +1,6 @@
 name: libac_dart
 description: "Aria's Creations code library"
-version: 1.3.010625+0228
+version: 1.3.010625+1127
 homepage: "https://zontreck.com"
 
 environment: