LG Magic Remote

[StratusFearMe21]

Hello, I am attempting to make a lightweight device driver for the LG Magic Remote. However, when I try to connect to it through l2cap it errors out with an os error 111. This is my code so far. It just tries to connect to the Magic Remote and it begins to receive packets.

use bluer::{
    l2cap::{SocketAddr, Stream, PSM_LE_DYN_START},
    Address,
};
use tokio::io::AsyncReadExt;

#[tokio::main]
async fn main() -> bluer::Result<()> {
    let addr: Address = "7C:02:BC:C5:14:3B".parse().unwrap();
    let socket_addr = SocketAddr::new(addr, bluer::AddressType::LePublic, PSM_LE_DYN_START + 5);
    println!("Connecting to magic remote");
    let mut stream = Stream::connect(socket_addr).await?;
    println!("Local address: {:?}", stream.as_ref().local_addr()?);
    println!("Remote address: {:?}", stream.peer_addr()?);
    println!("Recv MTU: {}", stream.as_ref().recv_mtu()?);
    println!("Security: {:?}", stream.as_ref().security()?);

    loop {
        let mut hello_buf = [0u8; 30];
        stream
            .read_exact(&mut hello_buf)
            .await
            .expect("read failed");
        println!("Received: {:?}", hello_buf);
    }
}

This is what it prints out

Connecting to magic remote
Local address: SocketAddr { addr: E0:D4:E8:38:4D:65, addr_type: LePublic, psm: 133, cid: 64 }
Remote address: SocketAddr { addr: 7C:02:BC:C5:14:3B, addr_type: LePublic, psm: 133, cid: 0 }
Recv MTU: 672
Security: Security { level: Medium, key_size: 0 }
thread 'main' panicked at 'read failed: Os { code: 111, kind: ConnectionRefused, message: "Connection refused" }', src/main.rs:23:14
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

Any ideas? Thanks!

[StratusFearMe21]

P.S there's no evidence of errors caused by app when I run it and then run sudo systemctl status bluetooth

[surban]

1. Are you sure that the LG Magic Remote is accepting L2CAP connections?
2. Are you sure that the port number is correct (PSM_LE_DYN_START + 5 in your case)?

[StratusFearMe21]

Well what I do know, is that according to Wireshark, when I connect the magic remote to my laptop, the magic remote will constantly send packets to my computer that look like this

All I want to do is gain direct access to these packets.

[StratusFearMe21]

I suspect the protocol is as follows

• X Velocity > 64-bit floating point
• Y Velocity > 64-bit floating point
• Button currently pressed > 16 bit unsigned integer
• Null byte > 8 bit unsigned integer

[surban]

Please try running gattcat discover [device-address] and post its output here.

You can install gattcat using cargo install bluer-tools.