🗂️ minecraft-packet-logger

A small Node.js proxy to log the packets between your client and a server.

This proxy is fully based on protocol version 754 (Minecraft verion 1.16.5), it might break on other versions!

How to use

Notes

• You need to have Node.js and npm installed to use this! (Installing Node.js will automatically install npm on Windows and MacOS)
• The proxy runs on port 25565 so make sure no other application is using that port!

Steps

1. Download or clone this repository. (You can do Code > Download ZIP)
2. Edit the options.js file with the options you want.
3. Open the command terminal of your comptuer and navigate to the project folder.
4. Run the command npm install (or npm i). (You only have to do this the first time you run this proxy)
5. Start Minecraft.
6. Start the proxy by typing npm start.

If you want to stop the proxy press CTRL + C, then type Y (for yes) and press enter. You can also press CTRL + C again instead of typing Y.

How it works

When you run npm start it will start the proxy. The proxy is just a server running on port 25565 (default Minecraft port) and when a client connects, it will start a client connection to the Minecraft server defined in options.js. Then whatever data the client sends to the proxy, it will send to the connection it has with the Minecraft server.

When the client sends data to the proxy

Client ====> Proxy ====> Minecraft server

When the Minecraft server sends data to the proxy

Client <==== Proxy <==== Minecraft server

All data goes throught the proxy which will allows the proxy to log all of it without affecting the connection. It acts as an intermediary between the client and Minecraft server.

Security

Since 1.3.1, Minecraft uses encrypted connections for servers, unless the server is in offline/"cracked" mode. This proxy supports encrypted connections with the Minecraft servers. This does mean that the proxy needs an 'accessToken' from your account, to authenticate the secure connection with Mojang. Since you can't authenticate a user connecting to a Minecraft server twice, the connection between the proxy and your client can't be encrypted. This shouldn't matter though, unless you connect to this proxy through a remote connection.

If you want to read encrypted packets, then you need to turn on the decrypt_encrypted_packets option in options.js The program will automatically try to get your 'accessToken'. Getting the 'accessToken' can fail if you use a modded Minecraft launcher (modded clients should be fine, but modded launchers might not). If you leave the option turned off, or the proxy can't get the 'accessToken', then it won't be able to read encrypted connections. All features will still work, like reading unencrypted packets. You're never forced to turn the feature on.

Your 'accessToken' will never be stored or send anywhere.