73 lines
2.2 KiB
Rust
73 lines
2.2 KiB
Rust
|
use anyhow::Result;
|
||
|
|
use std::net::{IpAddr, SocketAddr, TcpStream};
|
||
|
|
use std::time::Duration;
|
||
|
|
use tracing::{debug, info};
|
||
|
|
|
||
|
|
use crate::Router;
|
||
|
|
|
||
|
|
const SSH_PORT: u16 = 22;
|
||
|
|
const PROBE_TIMEOUT: Duration = Duration::from_millis(500);
|
||
|
|
|
||
|
|
/// Scan a CIDR subnet and return IP addresses of OpenWrt routers.
|
||
|
|
///
|
||
|
|
/// Probes TCP/22, then verifies /etc/openwrt_release over SSH.
|
||
|
|
/// `ssh_user` and `ssh_password` are used for the verification probe only.
|
||
|
|
pub async fn scan_subnet(
|
||
|
|
subnet_base: [u8; 4],
|
||
|
|
prefix_len: u8,
|
||
|
|
ssh_user: &str,
|
||
|
|
ssh_password: &str,
|
||
|
|
) -> Vec<IpAddr> {
|
||
|
|
let host_count = host_count_for_prefix(prefix_len);
|
||
|
|
let base_u32 = u32::from_be_bytes(subnet_base);
|
||
|
|
let mask = !((1u32 << (32 - prefix_len)) - 1);
|
||
|
|
let network = base_u32 & mask;
|
||
|
|
|
||
|
|
let mut candidates = Vec::new();
|
||
|
|
for i in 1..host_count {
|
||
|
|
let ip_u32 = network + i;
|
||
|
|
let ip = IpAddr::V4(std::net::Ipv4Addr::from(ip_u32));
|
||
|
|
if tcp_reachable(ip, SSH_PORT) {
|
||
|
|
candidates.push(ip);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
info!("{} hosts with TCP/22 open in /{}", candidates.len(), prefix_len);
|
||
|
|
|
||
|
|
let mut routers = Vec::new();
|
||
|
|
for ip in candidates {
|
||
|
|
match verify_openwrt(ip, ssh_user, ssh_password) {
|
||
|
|
Ok(true) => {
|
||
|
|
info!("OpenWrt detected at {}", ip);
|
||
|
|
routers.push(ip);
|
||
|
|
}
|
||
|
|
Ok(false) => debug!("{} is not OpenWrt", ip),
|
||
|
|
Err(e) => debug!("{} probe failed: {}", ip, e),
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
routers
|
||
|
|
}
|
||
|
|
|
||
|
|
/// Check whether a known IP is an OpenWrt router.
|
||
|
|
pub fn probe(ip: IpAddr, ssh_user: &str, ssh_password: &str) -> Result<bool> {
|
||
|
|
verify_openwrt(ip, ssh_user, ssh_password)
|
||
|
|
}
|
||
|
|
|
||
|
|
fn tcp_reachable(ip: IpAddr, port: u16) -> bool {
|
||
|
|
TcpStream::connect_timeout(&SocketAddr::new(ip, port), PROBE_TIMEOUT).is_ok()
|
||
|
|
}
|
||
|
|
|
||
|
|
fn verify_openwrt(ip: IpAddr, user: &str, password: &str) -> Result<bool> {
|
||
|
|
let router = Router::connect_password(&ip.to_string(), SSH_PORT, user, password)?;
|
||
|
|
let (out, code) = router.run("cat /etc/openwrt_release")?;
|
||
|
|
Ok(code == 0 && out.contains("OpenWrt"))
|
||
|
|
}
|
||
|
|
|
||
|
|
fn host_count_for_prefix(prefix_len: u8) -> u32 {
|
||
|
|
if prefix_len >= 32 {
|
||
|
|
return 1;
|
||
|
|
}
|
||
|
|
1u32 << (32 - prefix_len)
|
||
|
|
}
|