feat: erase contents of private messages before adding to binary

blurite · Jul 8, 2024 · 85c0405 · 85c0405
1 parent 14f9f95
commit 85c0405
Showing 1 changed file with 30 additions and 1 deletion.
diff --git a/proxy/src/main/kotlin/net/rsprox/proxy/server/ServerGameHandler.kt b/proxy/src/main/kotlin/net/rsprox/proxy/server/ServerGameHandler.kt
@@ -3,8 +3,11 @@ package net.rsprox.proxy.server
 import io.netty.channel.Channel
 import io.netty.channel.ChannelHandlerContext
 import io.netty.channel.SimpleChannelInboundHandler
+import net.rsprot.buffer.extensions.gjstr
+import net.rsprot.buffer.extensions.pjstr
 import net.rsprox.proxy.binary.StreamDirection
 import net.rsprox.proxy.channel.getBinaryBlob
+import net.rsprox.proxy.huffman.HuffmanProvider
 import net.rsprox.proxy.server.prot.GameServerProt
 
 public class ServerGameHandler(
@@ -14,7 +17,33 @@ public class ServerGameHandler(
         ctx: ChannelHandlerContext,
         msg: ServerPacket<GameServerProt>,
     ) {
-        ctx.channel().getBinaryBlob().append(StreamDirection.ServerToClient, msg.encode(ctx.alloc(), mod = false))
         serverChannel.writeAndFlush(msg.encode(ctx.alloc()))
+        eraseSensitiveContents(ctx, msg)
+        ctx.channel().getBinaryBlob().append(
+            StreamDirection.ServerToClient,
+            msg.encode(ctx.alloc(), mod = false),
+        )
+    }
+
+    private fun eraseSensitiveContents(
+        ctx: ChannelHandlerContext,
+        msg: ServerPacket<GameServerProt>,
+    ) {
+        // Both the message private and message private echo follow the same consistent structure
+        // of [String: name, EncodedString: contents]
+        if (msg.prot == GameServerProt.MESSAGE_PRIVATE ||
+            msg.prot == GameServerProt.MESSAGE_PRIVATE_ECHO
+        ) {
+            val payload = msg.payload
+            val readableBytes = payload.readableBytes()
+            val name = payload.gjstr()
+            val huffman = HuffmanProvider.get()
+            val contents = huffman.decode(payload)
+            val replacement = ctx.alloc().buffer(readableBytes)
+            replacement.pjstr(name)
+            // Replace the contents of private messages with asterisks of the same msg length
+            huffman.encode(replacement, "*".repeat(contents.length))
+            msg.replacePayload(replacement)
+        }
     }
 }