1 files changed, 133 insertions, 0 deletions

diff --git a/src/rcon.rs b/src/rcon.rs
new file mode 100644
index 0000000..b91fe9b
--- /dev/null
+++ b/src/rcon.rs
@@ -0,0 +1,133 @@
+use std::io::{Read, Write};
+use std::net::TcpStream;
+
+#[derive(Debug, Clone)]
+pub struct RconClient {
+    host: String,
+    port: u16,
+    password: String,
+}
+
+#[derive(Debug)]
+pub enum RconError {
+    Connection(String),
+    Auth(String),
+    Response(String),
+}
+
+impl std::fmt::Display for RconError {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            RconError::Connection(e) => write!(f, "RCON connection error: {e}"),
+            RconError::Auth(e) => write!(f, "RCON auth error: {e}"),
+            RconError::Response(e) => write!(f, "RCON response error: {e}"),
+        }
+    }
+}
+
+const SERVERDATA_AUTH: i32 = 3;
+const SERVERDATA_EXECCOMMAND: i32 = 2;
+
+impl RconClient {
+    pub fn new(password: String) -> Self {
+        Self {
+            host: "127.0.0.1".to_string(),
+            port: 25575,
+            password,
+        }
+    }
+
+    /// Non-blocking async wrapper — runs the blocking RCON call on a thread pool.
+    pub async fn send_command_async(&self, command: String) -> Result<String, RconError> {
+        let client = self.clone();
+        tokio::task::spawn_blocking(move || client.send_command(&command))
+            .await
+            .map_err(|e| RconError::Connection(e.to_string()))?
+    }
+
+    fn send_command(&self, command: &str) -> Result<String, RconError> {
+        let mut stream = TcpStream::connect(format!("{}:{}", self.host, self.port))
+            .map_err(|e| RconError::Connection(e.to_string()))?;
+
+        stream
+            .set_read_timeout(Some(std::time::Duration::from_secs(1)))
+            .ok();
+
+        let request_id = 1;
+        self.write_packet(&mut stream, request_id, SERVERDATA_AUTH, &self.password)?;
+        let response = self.read_packet(&mut stream)?;
+
+        if response.request_id == -1 {
+            return Err(RconError::Auth("Invalid RCON password".into()));
+        }
+
+        let cmd_id = 2;
+        self.write_packet(&mut stream, cmd_id, SERVERDATA_EXECCOMMAND, command)?;
+
+        let response = self.read_packet(&mut stream)?;
+        // Second packet is an end marker — some servers send it, some don't; ignore errors
+        let _ = self.read_packet(&mut stream);
+
+        Ok(response.body)
+    }
+
+    fn write_packet(
+        &self,
+        stream: &mut TcpStream,
+        request_id: i32,
+        packet_type: i32,
+        body: &str,
+    ) -> Result<(), RconError> {
+        let body_bytes = body.as_bytes();
+        let length = 10 + body_bytes.len() as i32;
+
+        let mut packet = Vec::with_capacity(4 + length as usize);
+        packet.extend_from_slice(&length.to_le_bytes());
+        packet.extend_from_slice(&request_id.to_le_bytes());
+        packet.extend_from_slice(&packet_type.to_le_bytes());
+        packet.extend_from_slice(body_bytes);
+        packet.extend_from_slice(&[0u8, 0u8]);
+
+        stream
+            .write_all(&packet)
+            .map_err(|e| RconError::Connection(e.to_string()))?;
+
+        Ok(())
+    }
+
+    fn read_packet(&self, stream: &mut TcpStream) -> Result<RconPacket, RconError> {
+        let mut length_buf = [0u8; 4];
+        stream
+            .read_exact(&mut length_buf)
+            .map_err(|e| RconError::Response(format!("Failed to read length: {e}")))?;
+
+        let length = i32::from_le_bytes(length_buf);
+        if length < 10 {
+            return Err(RconError::Response("Packet too short".into()));
+        }
+
+        let mut payload = vec![0u8; length as usize];
+        stream
+            .read_exact(&mut payload)
+            .map_err(|e| RconError::Response(format!("Failed to read payload: {e}")))?;
+
+        let request_id = i32::from_le_bytes([payload[0], payload[1], payload[2], payload[3]]);
+        let packet_type = i32::from_le_bytes([payload[4], payload[5], payload[6], payload[7]]);
+
+        let body_bytes = &payload[8..payload.len() - 2];
+        let body = String::from_utf8_lossy(body_bytes).to_string();
+
+        Ok(RconPacket {
+            request_id,
+            packet_type,
+            body,
+        })
+    }
+}
+
+#[derive(Debug)]
+struct RconPacket {
+    request_id: i32,
+    packet_type: i32,
+    body: String,
+}