Files
initrd/src/cmd/init/sshd.rs
Mikaël Cluseau c97ec190d0 introduce rust
2025-06-23 01:30:23 +02:00

92 lines
2.5 KiB
Rust

use log::{info, warn};
use std::fs;
use std::io::Write;
use std::os::unix::fs::PermissionsExt;
use std::process::Stdio;
use tokio::net;
use tokio::process::Command;
use super::{retry_or_ignore, Config};
pub async fn start(cfg: &Config) {
retry_or_ignore(async || {
info!("ssh: writing authorized keys");
let ssh_dir = "/root/.ssh";
let authorized_keys = format!("{ssh_dir}/authorized_keys");
fs::create_dir_all(ssh_dir)?;
fs::set_permissions(ssh_dir, fs::Permissions::from_mode(0o700))?;
let mut ak = Vec::new();
for auth in &cfg.auths {
writeln!(ak, "{} {}", auth.ssh_key, auth.name)?;
}
fs::write(authorized_keys, ak)?;
Ok(())
})
.await;
retry_or_ignore(async || {
let mut sshd_args = Vec::new();
sshd_args.extend(["-i", "-E", "/var/log/sshd.log"]);
for key_path in cfg.ssh.keys.iter() {
if !fs::exists(key_path).is_ok_and(|b| b) {
info!("ssh: host key not found (ignored): {key_path}");
continue;
}
sshd_args.extend(["-h", key_path]);
}
let sshd_args = sshd_args.into_iter().map(String::from).collect();
// don't pre-start sshd as it should rarely be useful at this stage, use inetd-style.
let listen_addr = cfg.ssh.listen.clone();
info!("ssh: starting listener on {listen_addr}");
let listener = net::TcpListener::bind(listen_addr).await?;
tokio::spawn(handle_ssh_connections(listener, sshd_args));
Ok(())
})
.await;
}
async fn handle_ssh_connections(listener: net::TcpListener, sshd_args: Vec<String>) {
loop {
let (stream, remote) = match listener.accept().await {
Ok(v) => v,
Err(e) => {
warn!("ssh: listener stopped: {e}");
return;
}
};
info!("ssh: new connection from {remote}");
use std::os::unix::io::{AsRawFd, FromRawFd};
let fd = stream.as_raw_fd();
let mut cmd = Command::new("/usr/sbin/sshd");
cmd.args(&sshd_args);
cmd.stdin(unsafe { Stdio::from_raw_fd(fd) });
cmd.stdout(unsafe { Stdio::from_raw_fd(fd) });
cmd.stderr(Stdio::null());
match cmd.spawn() {
Ok(mut child) => {
tokio::spawn(async move { child.wait().await });
}
Err(e) => {
warn!("ssh: failed to start server: {e}");
}
}
}
}