A Valve RCON protocol implementation in Visual Basic .NET

This is a simple implementation of the Valve RCON protocol in Visual Basic .NET 2019 Community Edition (Framework 4.7.2). Whith this library/class you can connect/authenticate/send commands/receive responses from your gameserver.

More info: https://developer.valvesoftware.com/wiki/Source_RCON_Protocol

TESTED WITH:

• Counter-Strike 2
• Counter-Strike: Global Offensive
• Counter-Strike: Source
• (Older versions are not guaranteed)

Installation

• Navigate to https://github.com/fpaezf/Valve-RCON-protocol-in-VB.NET/releases and download the latest version.
• Import the RconClient class to your project or add a library reference.
• Add rcon_password "your-password" to your server.cfg file.

Usage

Dim serverIP As String = "82.223.49.142" 'String to declare server IP or host
Dim serverPort As Integer = 27015 'Integer to declare server port
Dim serverPassword As String = "your-password" 'String to declare RCON password

Dim RCON As New RconClient 'Create a new RconClient
RCON.Connect(serverIP, serverPort) 'Connect to the server IP/HOST:PORT
RCON.Authorize(serverPassword) 'Send password to authenticate
   If RCON.Authorized = True And RCON.Connected = True Then 'If no errors, you can now send commands
      Dim a As String = RCON.SendCommand("status") 'Store in a string the server response to command "status"
      RichTextBox1.AppendText(a) 'Append server response to RichTextBox.Text
   End If
RCON.Close() 'Close connection to the server

Data visualization

If you put the server output string in a TextBox control the lines will be concatenated because of the return carriage chars. To visualize data correctly please, use RichTextBox control.

Building RCON packets

Both requests and responses are sent as TCP packets. Their payload follows the following basic structure:

• Size (Integer)
• ID (Integer)
• Type (Integer)
• Body (null-terminated string encoded in ASCII)
• Empty String (Empty null-terminated string encoded in ASCII)

This is how i build the packet to request authorization:

Dim Packet As Byte() = New Byte(CByte((4 + 4 + 4 + password.Length + 1))) {} 'Size + ID + Type + Command + Null
Packet(0) = password.Length + 9         'Packet Size (Integer)
Packet(4) = 99                          'Request Id (Integer between 1 and 99)
Packet(8) = 3                           'Request packet type: 3 = SERVERDATA_AUTH request
For X As Integer = 0 To password.Length - 1
     Packet(12 + X) = System.Text.Encoding.UTF8.GetBytes(password(X))(0) 'Command
Next