aerogramme/aero-proto/sasl.rs
2024-03-08 08:17:03 +01:00

140 lines
4.5 KiB
Rust

use std::net::SocketAddr;
use anyhow::{anyhow, bail, Result};
use futures::stream::{FuturesUnordered, StreamExt};
use tokio::io::BufStream;
use tokio::io::{AsyncBufReadExt, AsyncWriteExt};
use tokio::net::{TcpListener, TcpStream};
use tokio::sync::watch;
use aero_user::config::AuthConfig;
use aero_user::login::ArcLoginProvider;
pub struct AuthServer {
login_provider: ArcLoginProvider,
bind_addr: SocketAddr,
}
impl AuthServer {
pub fn new(config: AuthConfig, login_provider: ArcLoginProvider) -> Self {
Self {
bind_addr: config.bind_addr,
login_provider,
}
}
pub async fn run(self: Self, mut must_exit: watch::Receiver<bool>) -> Result<()> {
let tcp = TcpListener::bind(self.bind_addr).await?;
tracing::info!(
"SASL Authentication Protocol listening on {:#}",
self.bind_addr
);
let mut connections = FuturesUnordered::new();
while !*must_exit.borrow() {
let wait_conn_finished = async {
if connections.is_empty() {
futures::future::pending().await
} else {
connections.next().await
}
};
let (socket, remote_addr) = tokio::select! {
a = tcp.accept() => a?,
_ = wait_conn_finished => continue,
_ = must_exit.changed() => continue,
};
tracing::info!("AUTH: accepted connection from {}", remote_addr);
let conn = tokio::spawn(
NetLoop::new(socket, self.login_provider.clone(), must_exit.clone()).run_error(),
);
connections.push(conn);
}
drop(tcp);
tracing::info!("AUTH server shutting down, draining remaining connections...");
while connections.next().await.is_some() {}
Ok(())
}
}
struct NetLoop {
login: ArcLoginProvider,
stream: BufStream<TcpStream>,
stop: watch::Receiver<bool>,
state: State,
read_buf: Vec<u8>,
write_buf: BytesMut,
}
impl NetLoop {
fn new(stream: TcpStream, login: ArcLoginProvider, stop: watch::Receiver<bool>) -> Self {
Self {
login,
stream: BufStream::new(stream),
state: State::Init,
stop,
read_buf: Vec::new(),
write_buf: BytesMut::new(),
}
}
async fn run_error(self) {
match self.run().await {
Ok(()) => tracing::info!("Auth session succeeded"),
Err(e) => tracing::error!(err=?e, "Auth session failed"),
}
}
async fn run(mut self) -> Result<()> {
loop {
tokio::select! {
read_res = self.stream.read_until(b'\n', &mut self.read_buf) => {
// Detect EOF / socket close
let bread = read_res?;
if bread == 0 {
tracing::info!("Reading buffer empty, connection has been closed. Exiting AUTH session.");
return Ok(())
}
// Parse command
let (_, cmd) = client_command(&self.read_buf).map_err(|_| anyhow!("Unable to parse command"))?;
tracing::trace!(cmd=?cmd, "Received command");
// Make some progress in our local state
self.state.progress(cmd, &self.login).await;
if matches!(self.state, State::Error) {
bail!("Internal state is in error, previous logs explain what went wrong");
}
// Build response
let srv_cmds = self.state.response();
srv_cmds.iter().try_for_each(|r| {
tracing::trace!(cmd=?r, "Sent command");
r.encode(&mut self.write_buf)
})?;
// Send responses if at least one command response has been generated
if !srv_cmds.is_empty() {
self.stream.write_all(&self.write_buf).await?;
self.stream.flush().await?;
}
// Reset buffers
self.read_buf.clear();
self.write_buf.clear();
},
_ = self.stop.changed() => {
tracing::debug!("Server is stopping, quitting this runner");
return Ok(())
}
}
}
}
}