IronScan - My Rust(y) Network Scanning Tool

I’ve written a NetScan in Rust, Just for Fun!

Hi!

Last week, I decided to try something new: I wanted to create my version of NMap!

For those who don’t know, NMap is a network scanning tool, used in a vast pool of situations (such as cybersecurity analysis, network setup etc.). This is very interesting, but you know me, I wanted to do it my way.

Fist Version

The first thing I thought was: How?????. I had no idea where to start.

I knew it was necessary to read users’ input, so I decided to create my input parser:

#[derive(Parser)]
struct Args {
    /// Target IP address
    target: String,
    /// Start port
    start_port: u16,
    /// End port
    end_port: u16,
}

As you might notice, I used clap::Parser for this.

After that, I was able to read inputs made like ADDRESS START_PORT END_PORT. Amazing!

The core of the first version is the following:

fn scan_port(addr: &str, port: u16) -> bool {
    let socket = format!("{}:{}", addr, port);
    let timeout = std::time::Duration::from_millis(300);

    match TcpStream::connect_timeout(&socket.to_socket_addrs().unwrap().next().unwrap(), timeout) {
        Ok(_) => true,
        Err(_) => false,
    }
}

Let’s break it down a bit!

The scan_port function checks if a specific port on a given address is open.

1. Socket Creation:

   let socket = format!("{}:{}", addr, port);
   

   This line formats the address and port into a socket string.

2. Timeout Setting:

   let timeout = std::time::Duration::from_millis(300);
   

   A timeout duration of 300 milliseconds is set for the connection attempt.

3. Connection Attempt:

   match TcpStream::connect_timeout(&socket.to_socket_addrs().unwrap().next().unwrap(), timeout) {
       Ok(_) => true,
       Err(_) => false,
   }
   

   The function attempts to connect to the socket with the specified timeout. If the connection is successful, it returns true; otherwise, it returns false.

In the main function I just call this and I am done!

Second Version

The second version is still under development, some of the things I’m adding are:

• Parallel scan
• Ping and ICMP messages
• UDP Scanning: Similar to TCP but with std::net::UdpSocket.
• Service Detection: Implement banner grabbing on open ports.

Conclusion

For now it ends here! I am learning a lot of new things about Rust and how to use it in real world scenarios!

Thanks for passing by,

See you soon!

Federico