Files
Stalwart/crates/smtp/src/inbound/spawn.rs
2023-08-28 19:44:23 +02:00

234 lines
9.0 KiB
Rust

/*
* Copyright (c) 2023 Stalwart Labs Ltd.
*
* This file is part of Stalwart Mail Server.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as
* published by the Free Software Foundation, either version 3 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
* in the LICENSE file at the top-level directory of this distribution.
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* You can be released from the requirements of the AGPLv3 license by
* purchasing a commercial license. Please contact licensing@stalw.art
* for more details.
*/
use std::time::Instant;
use tokio::{
io::{AsyncRead, AsyncWrite},
net::TcpStream,
};
use tokio_rustls::server::TlsStream;
use utils::listener::SessionManager;
use crate::{
core::{Session, SessionData, SessionParameters, SmtpSessionManager, State},
queue, reporting,
scripts::ScriptResult,
};
use super::IsTls;
impl SessionManager for SmtpSessionManager {
fn spawn(&self, session: utils::listener::SessionData<TcpStream>) {
// Create session
let mut session = Session {
core: self.inner.clone(),
instance: session.instance,
state: State::default(),
span: session.span,
stream: session.stream,
in_flight: vec![session.in_flight],
data: SessionData::new(session.local_ip, session.remote_ip, session.remote_port),
params: SessionParameters::default(),
};
tokio::spawn(async move {
// Enforce throttle
if session.is_allowed().await {
if session.instance.is_tls_implicit {
if let Ok(mut session) = session.into_tls().await {
if session.init_conn().await {
session.handle_conn().await;
}
}
} else if session.init_conn().await {
session.handle_conn().await;
}
}
});
}
fn shutdown(&self) {
// We spawn to avoid using async_trait
let core = self.inner.clone();
tokio::spawn(async move {
let _ = core.queue.tx.send(queue::Event::Stop).await;
let _ = core.report.tx.send(reporting::Event::Stop).await;
#[cfg(feature = "local_delivery")]
let _ = core.delivery_tx.send(utils::ipc::DeliveryEvent::Stop).await;
});
}
}
impl Session<TcpStream> {
pub async fn into_tls(self) -> Result<Session<TlsStream<TcpStream>>, ()> {
let span = self.span;
Ok(Session {
stream: self.instance.tls_accept(self.stream, &span).await?,
state: self.state,
data: self.data,
instance: self.instance,
core: self.core,
in_flight: self.in_flight,
params: self.params,
span,
})
}
pub async fn handle_conn(mut self) {
if self.handle_conn_().await && self.instance.tls_acceptor.is_some() {
if let Ok(session) = self.into_tls().await {
session.handle_conn().await;
}
}
}
}
impl Session<TlsStream<TcpStream>> {
pub async fn handle_conn(mut self) {
self.handle_conn_().await;
}
}
impl<T: AsyncRead + AsyncWrite + IsTls + Unpin> Session<T> {
pub async fn init_conn(&mut self) -> bool {
self.eval_session_params().await;
self.verify_ip_dnsbl().await;
// Sieve filtering
if let Some(script) = self.core.session.config.connect.script.eval(self).await {
if let ScriptResult::Reject(message) = self
.run_script(script.clone(), self.build_script_parameters())
.await
{
tracing::debug!(parent: &self.span,
context = "connect",
event = "sieve-reject",
reason = message);
let _ = self.write(message.as_bytes()).await;
return false;
}
}
let instance = self.instance.clone();
if self.write(instance.data.as_bytes()).await.is_err() {
return false;
}
true
}
pub async fn handle_conn_(&mut self) -> bool {
let mut buf = vec![0; 8192];
let mut shutdown_rx = self.instance.shutdown_rx.clone();
loop {
tokio::select! {
result = tokio::time::timeout(
self.params.timeout,
self.read(&mut buf)) => {
match result {
Ok(Ok(bytes_read)) => {
if bytes_read > 0 {
if Instant::now() < self.data.valid_until && bytes_read <= self.data.bytes_left {
self.data.bytes_left -= bytes_read;
match self.ingest(&buf[..bytes_read]).await {
Ok(true) => (),
Ok(false) => {
return true;
}
Err(_) => {
break;
}
}
} else if bytes_read > self.data.bytes_left {
self
.write(format!("451 4.7.28 {} Session exceeded transfer quota.\r\n", self.instance.hostname).as_bytes())
.await
.ok();
tracing::debug!(
parent: &self.span,
event = "disconnect",
reason = "transfer-limit",
"Client exceeded incoming transfer limit."
);
break;
} else {
self
.write(format!("453 4.3.2 {} Session open for too long.\r\n", self.instance.hostname).as_bytes())
.await
.ok();
tracing::debug!(
parent: &self.span,
event = "disconnect",
reason = "loiter",
"Session open for too long."
);
break;
}
} else {
tracing::debug!(
parent: &self.span,
event = "disconnect",
reason = "peer",
"Connection closed by peer."
);
break;
}
}
Ok(Err(_)) => {
break;
}
Err(_) => {
tracing::debug!(
parent: &self.span,
event = "disconnect",
reason = "timeout",
"Connection timed out."
);
self
.write(format!("221 2.0.0 {} Disconnecting inactive client.\r\n", self.instance.hostname).as_bytes())
.await
.ok();
break;
}
}
},
_ = shutdown_rx.changed() => {
tracing::debug!(
parent: &self.span,
event = "disconnect",
reason = "shutdown",
"Server shutting down."
);
self.write(b"421 4.3.0 Server shutting down.\r\n").await.ok();
break;
}
};
}
false
}
}