Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Fix dtls handshake potential hanging issue #631

Merged
merged 1 commit into from
Nov 17, 2024
Merged

Fix dtls handshake potential hanging issue #631

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
16 changes: 11 additions & 5 deletions dtls/src/conn/mod.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -10,7 +10,7 @@ use std::sync::Arc;
use async_trait::async_trait;
use log::*;
use portable_atomic::{AtomicBool, AtomicU16};
use tokio::sync::{mpsc, Mutex};
use tokio::sync::{mpsc, oneshot, Mutex};
use tokio::time::Duration;
use util::replay_detector::*;
use util::Conn;
Expand Down Expand Up @@ -64,7 +64,8 @@ struct ConnReaderContext {
cache: HandshakeCache,
cipher_suite: Arc<Mutex<Option<Box<dyn CipherSuite + Send + Sync>>>>,
remote_epoch: Arc<AtomicU16>,
handshake_tx: mpsc::Sender<mpsc::Sender<()>>,
// use additional oneshot sender to mimic rendezvous channel behavior
handshake_tx: mpsc::Sender<(oneshot::Sender<()>, mpsc::Sender<()>)>,
handshake_done_rx: mpsc::Receiver<()>,
packet_tx: Arc<mpsc::Sender<PacketSendRequest>>,
}
Expand Down Expand Up @@ -96,7 +97,8 @@ pub struct DTLSConn {
pub(crate) flights: Option<Vec<Packet>>,
pub(crate) cfg: HandshakeConfig,
pub(crate) retransmit: bool,
pub(crate) handshake_rx: mpsc::Receiver<mpsc::Sender<()>>,
// use additional oneshot sender to mimic rendezvous channel behavior
pub(crate) handshake_rx: mpsc::Receiver<(oneshot::Sender<()>, mpsc::Sender<()>)>,

pub(crate) packet_tx: Arc<mpsc::Sender<PacketSendRequest>>,
pub(crate) handle_queue_tx: mpsc::Sender<mpsc::Sender<()>>,
Expand Down Expand Up @@ -830,9 +832,13 @@ impl DTLSConn {

if has_handshake {
let (done_tx, mut done_rx) = mpsc::channel(1);

let rendezvous_at_handshake = async {
let (rendezvous_tx, rendezvous_rx) = oneshot::channel();
_ = ctx.handshake_tx.send((rendezvous_tx, done_tx)).await;
rendezvous_rx.await
};
tokio::select! {
_ = ctx.handshake_tx.send(done_tx) => {
_ = rendezvous_at_handshake => {
let mut wait_done_rx = true;
while wait_done_rx{
tokio::select!{
Expand Down
67 changes: 34 additions & 33 deletions dtls/src/handshaker.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -330,45 +330,46 @@ impl DTLSConn {

loop {
tokio::select! {
done = self.handshake_rx.recv() =>{
if done.is_none() {
done_senders = self.handshake_rx.recv() =>{
if done_senders.is_none() {
trace!("[handshake:{}] {} handshake_tx is dropped", srv_cli_str(self.state.is_client), self.current_flight.to_string());
return Err(Error::ErrAlertFatalOrClose);
}

//trace!("[handshake:{}] {} received handshake_rx", srv_cli_str(self.state.is_client), self.current_flight.to_string());
let result = self.current_flight.parse(&mut self.handle_queue_tx, &mut self.state, &self.cache, &self.cfg).await;
drop(done);
match result {
Err((alert, mut err)) => {
trace!("[handshake:{}] {} result alert:{:?}, err:{:?}",
srv_cli_str(self.state.is_client),
self.current_flight.to_string(),
alert,
err);

if let Some(alert) = alert {
let alert_err = self.notify(alert.alert_level, alert.alert_description).await;

if let Err(alert_err) = alert_err {
if err.is_some() {
err = Some(alert_err);
} else if let Some((rendezvous_tx, done_tx)) = done_senders {
rendezvous_tx.send(()).ok();
//trace!("[handshake:{}] {} received handshake_rx", srv_cli_str(self.state.is_client), self.current_flight.to_string());
let result = self.current_flight.parse(&mut self.handle_queue_tx, &mut self.state, &self.cache, &self.cfg).await;
drop(done_tx);
match result {
Err((alert, mut err)) => {
trace!("[handshake:{}] {} result alert:{:?}, err:{:?}",
srv_cli_str(self.state.is_client),
self.current_flight.to_string(),
alert,
err);

if let Some(alert) = alert {
let alert_err = self.notify(alert.alert_level, alert.alert_description).await;

if let Err(alert_err) = alert_err {
if err.is_some() {
err = Some(alert_err);
}
}
}
if let Some(err) = err {
return Err(err);
}
}
if let Some(err) = err {
return Err(err);
}
}
Ok(next_flight) => {
trace!("[handshake:{}] {} -> {}", srv_cli_str(self.state.is_client), self.current_flight.to_string(), next_flight.to_string());
if next_flight.is_last_recv_flight() && self.current_flight.to_string() == next_flight.to_string() {
return Ok(HandshakeState::Finished);
Ok(next_flight) => {
trace!("[handshake:{}] {} -> {}", srv_cli_str(self.state.is_client), self.current_flight.to_string(), next_flight.to_string());
if next_flight.is_last_recv_flight() && self.current_flight.to_string() == next_flight.to_string() {
return Ok(HandshakeState::Finished);
}
self.current_flight = next_flight;
return Ok(HandshakeState::Preparing);
}
self.current_flight = next_flight;
return Ok(HandshakeState::Preparing);
}
};
};
}
}

_ = retransmit_timer.as_mut() =>{
Expand Down
Loading