Over-engineered job-stealing multithreaded port scanner in Rust.

port_scanner.rs

extern crate rayon;

use std::io::{stdout, Write};
use std::net::{IpAddr, Ipv4Addr, TcpStream};
use rayon::prelude::*;

static MAX_PORT: u16 = 65535;

fn main() {
    let address = IpAddr::V4(Ipv4Addr::new(127, 0, 0, 1));

    println!("Testing ports from 0 to {}:", MAX_PORT);
    let open_ports = get_open_ports(MAX_PORT, address);
    eprintln!("");

    let stdout = stdout();
    let mut handle = stdout.lock();
    handle.write(b"Results:\n").unwrap();
    for port in &open_ports {
        handle.write(format!("{number:>width$}\n", number=port, width=5).as_bytes()).unwrap();
    }
}

fn get_open_ports(ports: u16, address: IpAddr) -> Vec<u16> {
    (0..ports).into_par_iter().filter(|&p| {
        eprint!(".");
        TcpStream::connect((address, p)).is_ok()
    }).collect()
}