-extern crate bytes;
-extern crate tokio;
-extern crate tokio_codec;
-extern crate futures;
-extern crate lightning;
-extern crate secp256k1;
+// This file is Copyright its original authors, visible in version control
+// history.
+//
+// This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
+// or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
+// You may not use this file except in accordance with one or both of these
+// licenses.
-use bytes::BufMut;
+//! A socket handling library for those running in Tokio environments who wish to use
+//! rust-lightning with native [`TcpStream`]s.
+//!
+//! Designed to be as simple as possible, the high-level usage is almost as simple as "hand over a
+//! [`TcpStream`] and a reference to a [`PeerManager`] and the rest is handled".
+//!
+//! The [`PeerManager`], due to the fire-and-forget nature of this logic, must be a reference,
+//! (e.g. an [`Arc`]) and must use the [`SocketDescriptor`] provided here as the [`PeerManager`]'s
+//! `SocketDescriptor` implementation.
+//!
+//! Three methods are exposed to register a new connection for handling in [`tokio::spawn`] calls;
+//! see their individual docs for details.
+//!
+//! [`PeerManager`]: lightning::ln::peer_handler::PeerManager
-use futures::future;
-use futures::future::Future;
-use futures::{AsyncSink, Stream, Sink};
-use futures::sync::mpsc;
+#![deny(rustdoc::broken_intra_doc_links)]
+#![deny(rustdoc::private_intra_doc_links)]
-use secp256k1::key::PublicKey;
+#![deny(missing_docs)]
+#![cfg_attr(docsrs, feature(doc_auto_cfg))]
+
+use bitcoin::secp256k1::PublicKey;
-use tokio::timer::Delay;
use tokio::net::TcpStream;
+use tokio::time;
+use tokio::sync::mpsc;
use lightning::ln::peer_handler;
use lightning::ln::peer_handler::SocketDescriptor as LnSocketTrait;
+use lightning::ln::peer_handler::APeerManager;
+use lightning::ln::msgs::SocketAddress;
-use std::mem;
+use std::ops::Deref;
+use std::task::{self, Poll};
+use std::future::Future;
use std::net::SocketAddr;
+use std::net::TcpStream as StdTcpStream;
use std::sync::{Arc, Mutex};
use std::sync::atomic::{AtomicU64, Ordering};
-use std::time::{Duration, Instant};
-use std::vec::Vec;
+use std::time::Duration;
+use std::pin::Pin;
use std::hash::Hash;
static ID_COUNTER: AtomicU64 = AtomicU64::new(0);
-/// A connection to a remote peer. Can be constructed either as a remote connection using
-/// Connection::setup_outbound o
-pub struct Connection {
- writer: Option<mpsc::Sender<bytes::Bytes>>,
- event_notify: mpsc::Sender<()>,
- pending_read: Vec<u8>,
- read_blocker: Option<futures::sync::oneshot::Sender<Result<(), ()>>>,
+// We only need to select over multiple futures in one place, and taking on the full `tokio/macros`
+// dependency tree in order to do so (which has broken our MSRV before) is excessive. Instead, we
+// define a trivial two- and three- select macro with the specific types we need and just use that.
+
+pub(crate) enum SelectorOutput {
+ A(Option<()>), B(Option<()>), C(tokio::io::Result<()>),
+}
+
+pub(crate) struct TwoSelector<
+ A: Future<Output=Option<()>> + Unpin, B: Future<Output=Option<()>> + Unpin
+> {
+ pub a: A,
+ pub b: B,
+}
+
+impl<
+ A: Future<Output=Option<()>> + Unpin, B: Future<Output=Option<()>> + Unpin
+> Future for TwoSelector<A, B> {
+ type Output = SelectorOutput;
+ fn poll(mut self: Pin<&mut Self>, ctx: &mut task::Context<'_>) -> Poll<SelectorOutput> {
+ match Pin::new(&mut self.a).poll(ctx) {
+ Poll::Ready(res) => { return Poll::Ready(SelectorOutput::A(res)); },
+ Poll::Pending => {},
+ }
+ match Pin::new(&mut self.b).poll(ctx) {
+ Poll::Ready(res) => { return Poll::Ready(SelectorOutput::B(res)); },
+ Poll::Pending => {},
+ }
+ Poll::Pending
+ }
+}
+
+pub(crate) struct ThreeSelector<
+ A: Future<Output=Option<()>> + Unpin, B: Future<Output=Option<()>> + Unpin, C: Future<Output=tokio::io::Result<()>> + Unpin
+> {
+ pub a: A,
+ pub b: B,
+ pub c: C,
+}
+
+impl<
+ A: Future<Output=Option<()>> + Unpin, B: Future<Output=Option<()>> + Unpin, C: Future<Output=tokio::io::Result<()>> + Unpin
+> Future for ThreeSelector<A, B, C> {
+ type Output = SelectorOutput;
+ fn poll(mut self: Pin<&mut Self>, ctx: &mut task::Context<'_>) -> Poll<SelectorOutput> {
+ match Pin::new(&mut self.a).poll(ctx) {
+ Poll::Ready(res) => { return Poll::Ready(SelectorOutput::A(res)); },
+ Poll::Pending => {},
+ }
+ match Pin::new(&mut self.b).poll(ctx) {
+ Poll::Ready(res) => { return Poll::Ready(SelectorOutput::B(res)); },
+ Poll::Pending => {},
+ }
+ match Pin::new(&mut self.c).poll(ctx) {
+ Poll::Ready(res) => { return Poll::Ready(SelectorOutput::C(res)); },
+ Poll::Pending => {},
+ }
+ Poll::Pending
+ }
+}
+
+/// Connection contains all our internal state for a connection - we hold a reference to the
+/// Connection object (in an Arc<Mutex<>>) in each SocketDescriptor we create as well as in the
+/// read future (which is returned by schedule_read).
+struct Connection {
+ writer: Option<Arc<TcpStream>>,
+ // Because our PeerManager is templated by user-provided types, and we can't (as far as I can
+ // tell) have a const RawWakerVTable built out of templated functions, we need some indirection
+ // between being woken up with write-ready and calling PeerManager::write_buffer_space_avail.
+ // This provides that indirection, with a Sender which gets handed to the PeerManager Arc on
+ // the schedule_read stack.
+ //
+ // An alternative (likely more effecient) approach would involve creating a RawWakerVTable at
+ // runtime with functions templated by the Arc<PeerManager> type, calling
+ // write_buffer_space_avail directly from tokio's write wake, however doing so would require
+ // more unsafe voodo than I really feel like writing.
+ write_avail: mpsc::Sender<()>,
+ // When we are told by rust-lightning to pause read (because we have writes backing up), we do
+ // so by setting read_paused. At that point, the read task will stop reading bytes from the
+ // socket. To wake it up (without otherwise changing its state, we can push a value into this
+ // Sender.
+ read_waker: mpsc::Sender<()>,
read_paused: bool,
- need_disconnect: bool,
+ rl_requested_disconnect: bool,
id: u64,
}
impl Connection {
- fn schedule_read(peer_manager: Arc<peer_handler::PeerManager<SocketDescriptor>>, us: Arc<Mutex<Self>>, reader: futures::stream::SplitStream<tokio_codec::Framed<TcpStream, tokio_codec::BytesCodec>>) {
- let us_ref = us.clone();
- let us_close_ref = us.clone();
- let peer_manager_ref = peer_manager.clone();
- tokio::spawn(reader.for_each(move |b| {
- let pending_read = b.to_vec();
- {
- let mut lock = us_ref.lock().unwrap();
- assert!(lock.pending_read.is_empty());
- if lock.read_paused {
- lock.pending_read = pending_read;
- let (sender, blocker) = futures::sync::oneshot::channel();
- lock.read_blocker = Some(sender);
- return future::Either::A(blocker.then(|_| { Ok(()) }));
- }
+ async fn poll_event_process<PM: Deref + 'static + Send + Sync>(
+ peer_manager: PM,
+ mut event_receiver: mpsc::Receiver<()>,
+ ) where PM::Target: APeerManager<Descriptor = SocketDescriptor> {
+ loop {
+ if event_receiver.recv().await.is_none() {
+ return;
}
- //TODO: There's a race where we don't meet the requirements of disconnect_socket if its
- //called right here, after we release the us_ref lock in the scope above, but before we
- //call read_event!
- match peer_manager.read_event(&mut SocketDescriptor::new(us_ref.clone(), peer_manager.clone()), pending_read) {
- Ok(pause_read) => {
- if pause_read {
- let mut lock = us_ref.lock().unwrap();
- lock.read_paused = true;
+ peer_manager.as_ref().process_events();
+ }
+ }
+
+ async fn schedule_read<PM: Deref + 'static + Send + Sync + Clone>(
+ peer_manager: PM,
+ us: Arc<Mutex<Self>>,
+ reader: Arc<TcpStream>,
+ mut read_wake_receiver: mpsc::Receiver<()>,
+ mut write_avail_receiver: mpsc::Receiver<()>,
+ ) where PM::Target: APeerManager<Descriptor = SocketDescriptor> {
+ // Create a waker to wake up poll_event_process, above
+ let (event_waker, event_receiver) = mpsc::channel(1);
+ tokio::spawn(Self::poll_event_process(peer_manager.clone(), event_receiver));
+
+ // 4KiB is nice and big without handling too many messages all at once, giving other peers
+ // a chance to do some work.
+ let mut buf = [0; 4096];
+
+ let mut our_descriptor = SocketDescriptor::new(us.clone());
+ // An enum describing why we did/are disconnecting:
+ enum Disconnect {
+ // Rust-Lightning told us to disconnect, either by returning an Err or by calling
+ // SocketDescriptor::disconnect_socket.
+ // In this case, we do not call peer_manager.socket_disconnected() as Rust-Lightning
+ // already knows we're disconnected.
+ CloseConnection,
+ // The connection was disconnected for some other reason, ie because the socket was
+ // closed.
+ // In this case, we do need to call peer_manager.socket_disconnected() to inform
+ // Rust-Lightning that the socket is gone.
+ PeerDisconnected
+ }
+ let disconnect_type = loop {
+ let read_paused = {
+ let us_lock = us.lock().unwrap();
+ if us_lock.rl_requested_disconnect {
+ break Disconnect::CloseConnection;
+ }
+ us_lock.read_paused
+ };
+ // TODO: Drop the Box'ing of the futures once Rust has pin-on-stack support.
+ let select_result = if read_paused {
+ TwoSelector {
+ a: Box::pin(write_avail_receiver.recv()),
+ b: Box::pin(read_wake_receiver.recv()),
+ }.await
+ } else {
+ ThreeSelector {
+ a: Box::pin(write_avail_receiver.recv()),
+ b: Box::pin(read_wake_receiver.recv()),
+ c: Box::pin(reader.readable()),
+ }.await
+ };
+ match select_result {
+ SelectorOutput::A(v) => {
+ assert!(v.is_some()); // We can't have dropped the sending end, its in the us Arc!
+ if peer_manager.as_ref().write_buffer_space_avail(&mut our_descriptor).is_err() {
+ break Disconnect::CloseConnection;
+ }
+ },
+ SelectorOutput::B(some) => {
+ // The mpsc Receiver should only return `None` if the write side has been
+ // dropped, but that shouldn't be possible since its referenced by the Self in
+ // `us`.
+ debug_assert!(some.is_some());
+ },
+ SelectorOutput::C(res) => {
+ if res.is_err() { break Disconnect::PeerDisconnected; }
+ match reader.try_read(&mut buf) {
+ Ok(0) => break Disconnect::PeerDisconnected,
+ Ok(len) => {
+ let read_res = peer_manager.as_ref().read_event(&mut our_descriptor, &buf[0..len]);
+ let mut us_lock = us.lock().unwrap();
+ match read_res {
+ Ok(pause_read) => {
+ if pause_read {
+ us_lock.read_paused = true;
+ }
+ },
+ Err(_) => break Disconnect::CloseConnection,
+ }
+ },
+ Err(e) if e.kind() == std::io::ErrorKind::WouldBlock => {
+ // readable() is allowed to spuriously wake, so we have to handle
+ // WouldBlock here.
+ },
+ Err(_) => break Disconnect::PeerDisconnected,
}
},
- Err(e) => {
- us_ref.lock().unwrap().need_disconnect = false;
- return future::Either::B(future::result(Err(std::io::Error::new(std::io::ErrorKind::InvalidData, e))));
- }
}
+ let _ = event_waker.try_send(());
- if let Err(e) = us_ref.lock().unwrap().event_notify.try_send(()) {
- // Ignore full errors as we just need them to poll after this point, so if the user
- // hasn't received the last send yet, it doesn't matter.
- assert!(e.is_full());
- }
+ // At this point we've processed a message or two, and reset the ping timer for this
+ // peer, at least in the "are we still receiving messages" context, if we don't give up
+ // our timeslice to another task we may just spin on this peer, starving other peers
+ // and eventually disconnecting them for ping timeouts. Instead, we explicitly yield
+ // here.
+ let _ = tokio::task::yield_now().await;
+ };
+ us.lock().unwrap().writer.take();
+ if let Disconnect::PeerDisconnected = disconnect_type {
+ peer_manager.as_ref().socket_disconnected(&our_descriptor);
+ peer_manager.as_ref().process_events();
+ }
+ }
- future::Either::B(future::result(Ok(())))
- }).then(move |_| {
- if us_close_ref.lock().unwrap().need_disconnect {
- peer_manager_ref.disconnect_event(&SocketDescriptor::new(us_close_ref, peer_manager_ref.clone()));
- println!("Peer disconnected!");
- } else {
- println!("We disconnected peer!");
- }
- Ok(())
- }));
+ fn new(stream: StdTcpStream) -> (Arc<TcpStream>, mpsc::Receiver<()>, mpsc::Receiver<()>, Arc<Mutex<Self>>) {
+ // We only ever need a channel of depth 1 here: if we returned a non-full write to the
+ // PeerManager, we will eventually get notified that there is room in the socket to write
+ // new bytes, which will generate an event. That event will be popped off the queue before
+ // we call write_buffer_space_avail, ensuring that we have room to push a new () if, during
+ // the write_buffer_space_avail() call, send_data() returns a non-full write.
+ let (write_avail, write_receiver) = mpsc::channel(1);
+ // Similarly here - our only goal is to make sure the reader wakes up at some point after
+ // we shove a value into the channel which comes after we've reset the read_paused bool to
+ // false.
+ let (read_waker, read_receiver) = mpsc::channel(1);
+ stream.set_nonblocking(true).unwrap();
+ let tokio_stream = Arc::new(TcpStream::from_std(stream).unwrap());
+
+ (Arc::clone(&tokio_stream), write_receiver, read_receiver,
+ Arc::new(Mutex::new(Self {
+ writer: Some(tokio_stream), write_avail, read_waker, read_paused: false,
+ rl_requested_disconnect: false,
+ id: ID_COUNTER.fetch_add(1, Ordering::AcqRel)
+ })))
}
+}
- fn new(event_notify: mpsc::Sender<()>, stream: TcpStream) -> (futures::stream::SplitStream<tokio_codec::Framed<TcpStream, tokio_codec::BytesCodec>>, Arc<Mutex<Self>>) {
- let (writer, reader) = tokio_codec::Framed::new(stream, tokio_codec::BytesCodec::new()).split();
- let (send_sink, send_stream) = mpsc::channel(3);
- tokio::spawn(writer.send_all(send_stream.map_err(|_| -> std::io::Error {
- unreachable!();
- })).then(|_| {
- future::result(Ok(()))
- }));
- let us = Arc::new(Mutex::new(Self { writer: Some(send_sink), event_notify, pending_read: Vec::new(), read_blocker: None, read_paused: false, need_disconnect: true, id: ID_COUNTER.fetch_add(1, Ordering::AcqRel) }));
-
- (reader, us)
+fn get_addr_from_stream(stream: &StdTcpStream) -> Option<SocketAddress> {
+ match stream.peer_addr() {
+ Ok(SocketAddr::V4(sockaddr)) => Some(SocketAddress::TcpIpV4 {
+ addr: sockaddr.ip().octets(),
+ port: sockaddr.port(),
+ }),
+ Ok(SocketAddr::V6(sockaddr)) => Some(SocketAddress::TcpIpV6 {
+ addr: sockaddr.ip().octets(),
+ port: sockaddr.port(),
+ }),
+ Err(_) => None,
}
+}
+
+/// Process incoming messages and feed outgoing messages on the provided socket generated by
+/// accepting an incoming connection.
+///
+/// The returned future will complete when the peer is disconnected and associated handling
+/// futures are freed, though, because all processing futures are spawned with tokio::spawn, you do
+/// not need to poll the provided future in order to make progress.
+pub fn setup_inbound<PM: Deref + 'static + Send + Sync + Clone>(
+ peer_manager: PM,
+ stream: StdTcpStream,
+) -> impl std::future::Future<Output=()>
+where PM::Target: APeerManager<Descriptor = SocketDescriptor> {
+ let remote_addr = get_addr_from_stream(&stream);
+ let (reader, write_receiver, read_receiver, us) = Connection::new(stream);
+ #[cfg(test)]
+ let last_us = Arc::clone(&us);
- /// Process incoming messages and feed outgoing messages on the provided socket generated by
- /// accepting an incoming connection (by scheduling futures with tokio::spawn).
- ///
- /// You should poll the Receive end of event_notify and call get_and_clear_pending_events() on
- /// ChannelManager and ChannelMonitor objects.
- pub fn setup_inbound(peer_manager: Arc<peer_handler::PeerManager<SocketDescriptor>>, event_notify: mpsc::Sender<()>, stream: TcpStream) {
- let (reader, us) = Self::new(event_notify, stream);
+ let handle_opt = if peer_manager.as_ref().new_inbound_connection(SocketDescriptor::new(us.clone()), remote_addr).is_ok() {
+ Some(tokio::spawn(Connection::schedule_read(peer_manager, us, reader, read_receiver, write_receiver)))
+ } else {
+ // Note that we will skip socket_disconnected here, in accordance with the PeerManager
+ // requirements.
+ None
+ };
- if let Ok(_) = peer_manager.new_inbound_connection(SocketDescriptor::new(us.clone(), peer_manager.clone())) {
- Self::schedule_read(peer_manager, us, reader);
+ async move {
+ if let Some(handle) = handle_opt {
+ if let Err(e) = handle.await {
+ assert!(e.is_cancelled());
+ } else {
+ // This is certainly not guaranteed to always be true - the read loop may exit
+ // while there are still pending write wakers that need to be woken up after the
+ // socket shutdown(). Still, as a check during testing, to make sure tokio doesn't
+ // keep too many wakers around, this makes sense. The race should be rare (we do
+ // some work after shutdown()) and an error would be a major memory leak.
+ #[cfg(test)]
+ debug_assert!(Arc::try_unwrap(last_us).is_ok());
+ }
}
}
+}
+
+/// Process incoming messages and feed outgoing messages on the provided socket generated by
+/// making an outbound connection which is expected to be accepted by a peer with the given
+/// public key. The relevant processing is set to run free (via tokio::spawn).
+///
+/// The returned future will complete when the peer is disconnected and associated handling
+/// futures are freed, though, because all processing futures are spawned with tokio::spawn, you do
+/// not need to poll the provided future in order to make progress.
+pub fn setup_outbound<PM: Deref + 'static + Send + Sync + Clone>(
+ peer_manager: PM,
+ their_node_id: PublicKey,
+ stream: StdTcpStream,
+) -> impl std::future::Future<Output=()>
+where PM::Target: APeerManager<Descriptor = SocketDescriptor> {
+ let remote_addr = get_addr_from_stream(&stream);
+ let (reader, mut write_receiver, read_receiver, us) = Connection::new(stream);
+ #[cfg(test)]
+ let last_us = Arc::clone(&us);
+ let handle_opt = if let Ok(initial_send) = peer_manager.as_ref().new_outbound_connection(their_node_id, SocketDescriptor::new(us.clone()), remote_addr) {
+ Some(tokio::spawn(async move {
+ // We should essentially always have enough room in a TCP socket buffer to send the
+ // initial 10s of bytes. However, tokio running in single-threaded mode will always
+ // fail writes and wake us back up later to write. Thus, we handle a single
+ // std::task::Poll::Pending but still expect to write the full set of bytes at once
+ // and use a relatively tight timeout.
+ if let Ok(Ok(())) = tokio::time::timeout(Duration::from_millis(100), async {
+ loop {
+ match SocketDescriptor::new(us.clone()).send_data(&initial_send, true) {
+ v if v == initial_send.len() => break Ok(()),
+ 0 => {
+ write_receiver.recv().await;
+ // In theory we could check for if we've been instructed to disconnect
+ // the peer here, but its OK to just skip it - we'll check for it in
+ // schedule_read prior to any relevant calls into RL.
+ },
+ _ => {
+ eprintln!("Failed to write first full message to socket!");
+ peer_manager.as_ref().socket_disconnected(&SocketDescriptor::new(Arc::clone(&us)));
+ break Err(());
+ }
+ }
+ }
+ }).await {
+ Connection::schedule_read(peer_manager, us, reader, read_receiver, write_receiver).await;
+ }
+ }))
+ } else {
+ // Note that we will skip socket_disconnected here, in accordance with the PeerManager
+ // requirements.
+ None
+ };
- /// Process incoming messages and feed outgoing messages on the provided socket generated by
- /// making an outbound connection which is expected to be accepted by a peer with the given
- /// public key (by scheduling futures with tokio::spawn).
- ///
- /// You should poll the Receive end of event_notify and call get_and_clear_pending_events() on
- /// ChannelManager and ChannelMonitor objects.
- pub fn setup_outbound(peer_manager: Arc<peer_handler::PeerManager<SocketDescriptor>>, event_notify: mpsc::Sender<()>, their_node_id: PublicKey, stream: TcpStream) {
- let (reader, us) = Self::new(event_notify, stream);
-
- if let Ok(initial_send) = peer_manager.new_outbound_connection(their_node_id, SocketDescriptor::new(us.clone(), peer_manager.clone())) {
- if SocketDescriptor::new(us.clone(), peer_manager.clone()).send_data(&initial_send, true) == initial_send.len() {
- Self::schedule_read(peer_manager, us, reader);
+ async move {
+ if let Some(handle) = handle_opt {
+ if let Err(e) = handle.await {
+ assert!(e.is_cancelled());
} else {
- println!("Failed to write first full message to socket!");
+ // This is certainly not guaranteed to always be true - the read loop may exit
+ // while there are still pending write wakers that need to be woken up after the
+ // socket shutdown(). Still, as a check during testing, to make sure tokio doesn't
+ // keep too many wakers around, this makes sense. The race should be rare (we do
+ // some work after shutdown()) and an error would be a major memory leak.
+ #[cfg(test)]
+ debug_assert!(Arc::try_unwrap(last_us).is_ok());
}
}
}
+}
- /// Process incoming messages and feed outgoing messages on a new connection made to the given
- /// socket address which is expected to be accepted by a peer with the given public key (by
- /// scheduling futures with tokio::spawn).
- ///
- /// You should poll the Receive end of event_notify and call get_and_clear_pending_events() on
- /// ChannelManager and ChannelMonitor objects.
- pub fn connect_outbound(peer_manager: Arc<peer_handler::PeerManager<SocketDescriptor>>, event_notify: mpsc::Sender<()>, their_node_id: PublicKey, addr: SocketAddr) {
- let connect_timeout = Delay::new(Instant::now() + Duration::from_secs(10)).then(|_| {
- future::err(std::io::Error::new(std::io::ErrorKind::TimedOut, "timeout reached"))
- });
- tokio::spawn(TcpStream::connect(&addr).select(connect_timeout)
- .and_then(move |stream| {
- Connection::setup_outbound(peer_manager, event_notify, their_node_id, stream.0);
- future::ok(())
- }).or_else(|_| {
- //TODO: return errors somehow
- future::ok(())
- }));
- }
+/// Process incoming messages and feed outgoing messages on a new connection made to the given
+/// socket address which is expected to be accepted by a peer with the given public key (by
+/// scheduling futures with tokio::spawn).
+///
+/// Shorthand for TcpStream::connect(addr) with a timeout followed by setup_outbound().
+///
+/// Returns a future (as the fn is async) which needs to be polled to complete the connection and
+/// connection setup. That future then returns a future which will complete when the peer is
+/// disconnected and associated handling futures are freed, though, because all processing in said
+/// futures are spawned with tokio::spawn, you do not need to poll the second future in order to
+/// make progress.
+pub async fn connect_outbound<PM: Deref + 'static + Send + Sync + Clone>(
+ peer_manager: PM,
+ their_node_id: PublicKey,
+ addr: SocketAddr,
+) -> Option<impl std::future::Future<Output=()>>
+where PM::Target: APeerManager<Descriptor = SocketDescriptor> {
+ if let Ok(Ok(stream)) = time::timeout(Duration::from_secs(10), async { TcpStream::connect(&addr).await.map(|s| s.into_std().unwrap()) }).await {
+ Some(setup_outbound(peer_manager, their_node_id, stream))
+ } else { None }
+}
+
+const SOCK_WAKER_VTABLE: task::RawWakerVTable =
+ task::RawWakerVTable::new(clone_socket_waker, wake_socket_waker, wake_socket_waker_by_ref, drop_socket_waker);
+
+fn clone_socket_waker(orig_ptr: *const ()) -> task::RawWaker {
+ let new_waker = unsafe { Arc::from_raw(orig_ptr as *const mpsc::Sender<()>) };
+ let res = write_avail_to_waker(&new_waker);
+ // Don't decrement the refcount when dropping new_waker by turning it back `into_raw`.
+ let _ = Arc::into_raw(new_waker);
+ res
+}
+// When waking, an error should be fine. Most likely we got two send_datas in a row, both of which
+// failed to fully write, but we only need to call write_buffer_space_avail() once. Otherwise, the
+// sending thread may have already gone away due to a socket close, in which case there's nothing
+// to wake up anyway.
+fn wake_socket_waker(orig_ptr: *const ()) {
+ let sender = unsafe { &mut *(orig_ptr as *mut mpsc::Sender<()>) };
+ let _ = sender.try_send(());
+ drop_socket_waker(orig_ptr);
+}
+fn wake_socket_waker_by_ref(orig_ptr: *const ()) {
+ let sender_ptr = orig_ptr as *const mpsc::Sender<()>;
+ let sender = unsafe { &*sender_ptr };
+ let _ = sender.try_send(());
+}
+fn drop_socket_waker(orig_ptr: *const ()) {
+ let _orig_arc = unsafe { Arc::from_raw(orig_ptr as *mut mpsc::Sender<()>) };
+ // _orig_arc is now dropped
+}
+fn write_avail_to_waker(sender: &Arc<mpsc::Sender<()>>) -> task::RawWaker {
+ let new_ptr = Arc::into_raw(Arc::clone(&sender));
+ task::RawWaker::new(new_ptr as *const (), &SOCK_WAKER_VTABLE)
}
-#[derive(Clone)]
+/// The SocketDescriptor used to refer to sockets by a PeerHandler. This is pub only as it is a
+/// type in the template of PeerHandler.
pub struct SocketDescriptor {
conn: Arc<Mutex<Connection>>,
+ // We store a copy of the mpsc::Sender to wake the read task in an Arc here. While we can
+ // simply clone the sender and store a copy in each waker, that would require allocating for
+ // each waker. Instead, we can simply `Arc::clone`, creating a new reference and store the
+ // pointer in the waker.
+ write_avail_sender: Arc<mpsc::Sender<()>>,
id: u64,
- peer_manager: Arc<peer_handler::PeerManager<SocketDescriptor>>,
}
impl SocketDescriptor {
- fn new(conn: Arc<Mutex<Connection>>, peer_manager: Arc<peer_handler::PeerManager<SocketDescriptor>>) -> Self {
- let id = conn.lock().unwrap().id;
- Self { conn, id, peer_manager }
+ fn new(conn: Arc<Mutex<Connection>>) -> Self {
+ let (id, write_avail_sender) = {
+ let us = conn.lock().unwrap();
+ (us.id, Arc::new(us.write_avail.clone()))
+ };
+ Self { conn, id, write_avail_sender }
}
}
impl peer_handler::SocketDescriptor for SocketDescriptor {
fn send_data(&mut self, data: &[u8], resume_read: bool) -> usize {
- macro_rules! schedule_read {
- ($us_ref: expr) => {
- tokio::spawn(future::lazy(move || -> Result<(), ()> {
- let mut read_data = Vec::new();
- {
- let mut us = $us_ref.conn.lock().unwrap();
- mem::swap(&mut read_data, &mut us.pending_read);
- }
- if !read_data.is_empty() {
- let mut us_clone = $us_ref.clone();
- match $us_ref.peer_manager.read_event(&mut us_clone, read_data) {
- Ok(pause_read) => {
- if pause_read { return Ok(()); }
- },
- Err(_) => {
- //TODO: Not actually sure how to do this
- return Ok(());
- }
- }
- }
- let mut us = $us_ref.conn.lock().unwrap();
- if let Some(sender) = us.read_blocker.take() {
- sender.send(Ok(())).unwrap();
- }
- us.read_paused = false;
- if let Err(e) = us.event_notify.try_send(()) {
- // Ignore full errors as we just need them to poll after this point, so if the user
- // hasn't received the last send yet, it doesn't matter.
- assert!(e.is_full());
- }
- Ok(())
- }));
- }
- }
-
+ // To send data, we take a lock on our Connection to access the TcpStream, writing to it if
+ // there's room in the kernel buffer, or otherwise create a new Waker with a
+ // SocketDescriptor in it which can wake up the write_avail Sender, waking up the
+ // processing future which will call write_buffer_space_avail and we'll end up back here.
let mut us = self.conn.lock().unwrap();
- if resume_read {
- let us_ref = self.clone();
- schedule_read!(us_ref);
- }
- if data.is_empty() { return 0; }
if us.writer.is_none() {
- us.read_paused = true;
+ // The writer gets take()n when it is time to shut down, so just fast-return 0 here.
return 0;
}
- let mut bytes = bytes::BytesMut::with_capacity(data.len());
- bytes.put(data);
- let write_res = us.writer.as_mut().unwrap().start_send(bytes.freeze());
- match write_res {
- Ok(res) => {
- match res {
- AsyncSink::Ready => {
- data.len()
- },
- AsyncSink::NotReady(_) => {
- us.read_paused = true;
- let us_ref = self.clone();
- tokio::spawn(us.writer.take().unwrap().flush().then(move |writer_res| -> Result<(), ()> {
- if let Ok(writer) = writer_res {
- {
- let mut us = us_ref.conn.lock().unwrap();
- us.writer = Some(writer);
- }
- schedule_read!(us_ref);
- } // we'll fire the disconnect event on the socket reader end
- Ok(())
- }));
- 0
+ if resume_read && us.read_paused {
+ // The schedule_read future may go to lock up but end up getting woken up by there
+ // being more room in the write buffer, dropping the other end of this Sender
+ // before we get here, so we ignore any failures to wake it up.
+ us.read_paused = false;
+ let _ = us.read_waker.try_send(());
+ }
+ if data.is_empty() { return 0; }
+ let waker = unsafe { task::Waker::from_raw(write_avail_to_waker(&self.write_avail_sender)) };
+ let mut ctx = task::Context::from_waker(&waker);
+ let mut written_len = 0;
+ loop {
+ match us.writer.as_ref().unwrap().poll_write_ready(&mut ctx) {
+ task::Poll::Ready(Ok(())) => {
+ match us.writer.as_ref().unwrap().try_write(&data[written_len..]) {
+ Ok(res) => {
+ debug_assert_ne!(res, 0);
+ written_len += res;
+ if written_len == data.len() { return written_len; }
+ },
+ Err(ref e) if e.kind() == std::io::ErrorKind::WouldBlock => {
+ continue;
+ }
+ Err(_) => return written_len,
}
- }
- },
- Err(_) => {
- // We'll fire the disconnected event on the socket reader end
- 0
- },
+ },
+ task::Poll::Ready(Err(_)) => return written_len,
+ task::Poll::Pending => {
+ // We're queued up for a write event now, but we need to make sure we also
+ // pause read given we're now waiting on the remote end to ACK (and in
+ // accordance with the send_data() docs).
+ us.read_paused = true;
+ // Further, to avoid any current pending read causing a `read_event` call, wake
+ // up the read_waker and restart its loop.
+ let _ = us.read_waker.try_send(());
+ return written_len;
+ },
+ }
}
}
fn disconnect_socket(&mut self) {
let mut us = self.conn.lock().unwrap();
- us.need_disconnect = true;
- us.read_paused = true;
+ us.rl_requested_disconnect = true;
+ // Wake up the sending thread, assuming it is still alive
+ let _ = us.write_avail.try_send(());
+ }
+}
+impl Clone for SocketDescriptor {
+ fn clone(&self) -> Self {
+ Self {
+ conn: Arc::clone(&self.conn),
+ id: self.id,
+ write_avail_sender: Arc::clone(&self.write_avail_sender),
+ }
}
}
impl Eq for SocketDescriptor {}
}
}
+#[cfg(test)]
+mod tests {
+ use lightning::ln::features::*;
+ use lightning::ln::msgs::*;
+ use lightning::ln::peer_handler::{MessageHandler, PeerManager};
+ use lightning::routing::gossip::NodeId;
+ use lightning::events::*;
+ use lightning::util::test_utils::TestNodeSigner;
+ use bitcoin::Network;
+ use bitcoin::blockdata::constants::ChainHash;
+ use bitcoin::secp256k1::{Secp256k1, SecretKey, PublicKey};
+
+ use tokio::sync::mpsc;
+
+ use std::mem;
+ use std::sync::atomic::{AtomicBool, Ordering};
+ use std::sync::{Arc, Mutex};
+ use std::time::Duration;
+
+ pub struct TestLogger();
+ impl lightning::util::logger::Logger for TestLogger {
+ fn log(&self, record: lightning::util::logger::Record) {
+ println!("{:<5} [{} : {}, {}] {}", record.level.to_string(), record.module_path, record.file, record.line, record.args);
+ }
+ }
+
+ struct MsgHandler{
+ expected_pubkey: PublicKey,
+ pubkey_connected: mpsc::Sender<()>,
+ pubkey_disconnected: mpsc::Sender<()>,
+ disconnected_flag: AtomicBool,
+ msg_events: Mutex<Vec<MessageSendEvent>>,
+ }
+ impl RoutingMessageHandler for MsgHandler {
+ fn handle_node_announcement(&self, _msg: &NodeAnnouncement) -> Result<bool, LightningError> { Ok(false) }
+ fn handle_channel_announcement(&self, _msg: &ChannelAnnouncement) -> Result<bool, LightningError> { Ok(false) }
+ fn handle_channel_update(&self, _msg: &ChannelUpdate) -> Result<bool, LightningError> { Ok(false) }
+ fn get_next_channel_announcement(&self, _starting_point: u64) -> Option<(ChannelAnnouncement, Option<ChannelUpdate>, Option<ChannelUpdate>)> { None }
+ fn get_next_node_announcement(&self, _starting_point: Option<&NodeId>) -> Option<NodeAnnouncement> { None }
+ fn peer_connected(&self, _their_node_id: &PublicKey, _init_msg: &Init, _inbound: bool) -> Result<(), ()> { Ok(()) }
+ fn handle_reply_channel_range(&self, _their_node_id: &PublicKey, _msg: ReplyChannelRange) -> Result<(), LightningError> { Ok(()) }
+ fn handle_reply_short_channel_ids_end(&self, _their_node_id: &PublicKey, _msg: ReplyShortChannelIdsEnd) -> Result<(), LightningError> { Ok(()) }
+ fn handle_query_channel_range(&self, _their_node_id: &PublicKey, _msg: QueryChannelRange) -> Result<(), LightningError> { Ok(()) }
+ fn handle_query_short_channel_ids(&self, _their_node_id: &PublicKey, _msg: QueryShortChannelIds) -> Result<(), LightningError> { Ok(()) }
+ fn provided_node_features(&self) -> NodeFeatures { NodeFeatures::empty() }
+ fn provided_init_features(&self, _their_node_id: &PublicKey) -> InitFeatures { InitFeatures::empty() }
+ fn processing_queue_high(&self) -> bool { false }
+ }
+ impl ChannelMessageHandler for MsgHandler {
+ fn handle_open_channel(&self, _their_node_id: &PublicKey, _msg: &OpenChannel) {}
+ fn handle_accept_channel(&self, _their_node_id: &PublicKey, _msg: &AcceptChannel) {}
+ fn handle_funding_created(&self, _their_node_id: &PublicKey, _msg: &FundingCreated) {}
+ fn handle_funding_signed(&self, _their_node_id: &PublicKey, _msg: &FundingSigned) {}
+ fn handle_channel_ready(&self, _their_node_id: &PublicKey, _msg: &ChannelReady) {}
+ fn handle_shutdown(&self, _their_node_id: &PublicKey, _msg: &Shutdown) {}
+ fn handle_closing_signed(&self, _their_node_id: &PublicKey, _msg: &ClosingSigned) {}
+ fn handle_update_add_htlc(&self, _their_node_id: &PublicKey, _msg: &UpdateAddHTLC) {}
+ fn handle_update_fulfill_htlc(&self, _their_node_id: &PublicKey, _msg: &UpdateFulfillHTLC) {}
+ fn handle_update_fail_htlc(&self, _their_node_id: &PublicKey, _msg: &UpdateFailHTLC) {}
+ fn handle_update_fail_malformed_htlc(&self, _their_node_id: &PublicKey, _msg: &UpdateFailMalformedHTLC) {}
+ fn handle_commitment_signed(&self, _their_node_id: &PublicKey, _msg: &CommitmentSigned) {}
+ fn handle_revoke_and_ack(&self, _their_node_id: &PublicKey, _msg: &RevokeAndACK) {}
+ fn handle_update_fee(&self, _their_node_id: &PublicKey, _msg: &UpdateFee) {}
+ fn handle_announcement_signatures(&self, _their_node_id: &PublicKey, _msg: &AnnouncementSignatures) {}
+ fn handle_channel_update(&self, _their_node_id: &PublicKey, _msg: &ChannelUpdate) {}
+ fn handle_open_channel_v2(&self, _their_node_id: &PublicKey, _msg: &OpenChannelV2) {}
+ fn handle_accept_channel_v2(&self, _their_node_id: &PublicKey, _msg: &AcceptChannelV2) {}
+ fn handle_stfu(&self, _their_node_id: &PublicKey, _msg: &Stfu) {}
+ #[cfg(dual_funding)]
+ fn handle_splice(&self, _their_node_id: &PublicKey, _msg: &Splice) {}
+ #[cfg(dual_funding)]
+ fn handle_splice_ack(&self, _their_node_id: &PublicKey, _msg: &SpliceAck) {}
+ #[cfg(dual_funding)]
+ fn handle_splice_locked(&self, _their_node_id: &PublicKey, _msg: &SpliceLocked) {}
+ fn handle_tx_add_input(&self, _their_node_id: &PublicKey, _msg: &TxAddInput) {}
+ fn handle_tx_add_output(&self, _their_node_id: &PublicKey, _msg: &TxAddOutput) {}
+ fn handle_tx_remove_input(&self, _their_node_id: &PublicKey, _msg: &TxRemoveInput) {}
+ fn handle_tx_remove_output(&self, _their_node_id: &PublicKey, _msg: &TxRemoveOutput) {}
+ fn handle_tx_complete(&self, _their_node_id: &PublicKey, _msg: &TxComplete) {}
+ fn handle_tx_signatures(&self, _their_node_id: &PublicKey, _msg: &TxSignatures) {}
+ fn handle_tx_init_rbf(&self, _their_node_id: &PublicKey, _msg: &TxInitRbf) {}
+ fn handle_tx_ack_rbf(&self, _their_node_id: &PublicKey, _msg: &TxAckRbf) {}
+ fn handle_tx_abort(&self, _their_node_id: &PublicKey, _msg: &TxAbort) {}
+ fn peer_disconnected(&self, their_node_id: &PublicKey) {
+ if *their_node_id == self.expected_pubkey {
+ self.disconnected_flag.store(true, Ordering::SeqCst);
+ self.pubkey_disconnected.clone().try_send(()).unwrap();
+ }
+ }
+ fn peer_connected(&self, their_node_id: &PublicKey, _init_msg: &Init, _inbound: bool) -> Result<(), ()> {
+ if *their_node_id == self.expected_pubkey {
+ self.pubkey_connected.clone().try_send(()).unwrap();
+ }
+ Ok(())
+ }
+ fn handle_channel_reestablish(&self, _their_node_id: &PublicKey, _msg: &ChannelReestablish) {}
+ fn handle_error(&self, _their_node_id: &PublicKey, _msg: &ErrorMessage) {}
+ fn provided_node_features(&self) -> NodeFeatures { NodeFeatures::empty() }
+ fn provided_init_features(&self, _their_node_id: &PublicKey) -> InitFeatures { InitFeatures::empty() }
+ fn get_chain_hashes(&self) -> Option<Vec<ChainHash>> {
+ Some(vec![ChainHash::using_genesis_block(Network::Testnet)])
+ }
+ }
+ impl MessageSendEventsProvider for MsgHandler {
+ fn get_and_clear_pending_msg_events(&self) -> Vec<MessageSendEvent> {
+ let mut ret = Vec::new();
+ mem::swap(&mut *self.msg_events.lock().unwrap(), &mut ret);
+ ret
+ }
+ }
+
+ fn make_tcp_connection() -> (std::net::TcpStream, std::net::TcpStream) {
+ if let Ok(listener) = std::net::TcpListener::bind("127.0.0.1:9735") {
+ (std::net::TcpStream::connect("127.0.0.1:9735").unwrap(), listener.accept().unwrap().0)
+ } else if let Ok(listener) = std::net::TcpListener::bind("127.0.0.1:19735") {
+ (std::net::TcpStream::connect("127.0.0.1:19735").unwrap(), listener.accept().unwrap().0)
+ } else if let Ok(listener) = std::net::TcpListener::bind("127.0.0.1:9997") {
+ (std::net::TcpStream::connect("127.0.0.1:9997").unwrap(), listener.accept().unwrap().0)
+ } else if let Ok(listener) = std::net::TcpListener::bind("127.0.0.1:9998") {
+ (std::net::TcpStream::connect("127.0.0.1:9998").unwrap(), listener.accept().unwrap().0)
+ } else if let Ok(listener) = std::net::TcpListener::bind("127.0.0.1:9999") {
+ (std::net::TcpStream::connect("127.0.0.1:9999").unwrap(), listener.accept().unwrap().0)
+ } else if let Ok(listener) = std::net::TcpListener::bind("127.0.0.1:46926") {
+ (std::net::TcpStream::connect("127.0.0.1:46926").unwrap(), listener.accept().unwrap().0)
+ } else { panic!("Failed to bind to v4 localhost on common ports"); }
+ }
+
+ async fn do_basic_connection_test() {
+ let secp_ctx = Secp256k1::new();
+ let a_key = SecretKey::from_slice(&[1; 32]).unwrap();
+ let b_key = SecretKey::from_slice(&[1; 32]).unwrap();
+ let a_pub = PublicKey::from_secret_key(&secp_ctx, &a_key);
+ let b_pub = PublicKey::from_secret_key(&secp_ctx, &b_key);
+
+ let (a_connected_sender, mut a_connected) = mpsc::channel(1);
+ let (a_disconnected_sender, mut a_disconnected) = mpsc::channel(1);
+ let a_handler = Arc::new(MsgHandler {
+ expected_pubkey: b_pub,
+ pubkey_connected: a_connected_sender,
+ pubkey_disconnected: a_disconnected_sender,
+ disconnected_flag: AtomicBool::new(false),
+ msg_events: Mutex::new(Vec::new()),
+ });
+ let a_manager = Arc::new(PeerManager::new(MessageHandler {
+ chan_handler: Arc::clone(&a_handler),
+ route_handler: Arc::clone(&a_handler),
+ onion_message_handler: Arc::new(lightning::ln::peer_handler::IgnoringMessageHandler{}),
+ custom_message_handler: Arc::new(lightning::ln::peer_handler::IgnoringMessageHandler{}),
+ }, 0, &[1; 32], Arc::new(TestLogger()), Arc::new(TestNodeSigner::new(a_key))));
+
+ let (b_connected_sender, mut b_connected) = mpsc::channel(1);
+ let (b_disconnected_sender, mut b_disconnected) = mpsc::channel(1);
+ let b_handler = Arc::new(MsgHandler {
+ expected_pubkey: a_pub,
+ pubkey_connected: b_connected_sender,
+ pubkey_disconnected: b_disconnected_sender,
+ disconnected_flag: AtomicBool::new(false),
+ msg_events: Mutex::new(Vec::new()),
+ });
+ let b_manager = Arc::new(PeerManager::new(MessageHandler {
+ chan_handler: Arc::clone(&b_handler),
+ route_handler: Arc::clone(&b_handler),
+ onion_message_handler: Arc::new(lightning::ln::peer_handler::IgnoringMessageHandler{}),
+ custom_message_handler: Arc::new(lightning::ln::peer_handler::IgnoringMessageHandler{}),
+ }, 0, &[2; 32], Arc::new(TestLogger()), Arc::new(TestNodeSigner::new(b_key))));
+
+ // We bind on localhost, hoping the environment is properly configured with a local
+ // address. This may not always be the case in containers and the like, so if this test is
+ // failing for you check that you have a loopback interface and it is configured with
+ // 127.0.0.1.
+ let (conn_a, conn_b) = make_tcp_connection();
+
+ let fut_a = super::setup_outbound(Arc::clone(&a_manager), b_pub, conn_a);
+ let fut_b = super::setup_inbound(b_manager, conn_b);
+
+ tokio::time::timeout(Duration::from_secs(10), a_connected.recv()).await.unwrap();
+ tokio::time::timeout(Duration::from_secs(1), b_connected.recv()).await.unwrap();
+
+ a_handler.msg_events.lock().unwrap().push(MessageSendEvent::HandleError {
+ node_id: b_pub, action: ErrorAction::DisconnectPeer { msg: None }
+ });
+ assert!(!a_handler.disconnected_flag.load(Ordering::SeqCst));
+ assert!(!b_handler.disconnected_flag.load(Ordering::SeqCst));
+
+ a_manager.process_events();
+ tokio::time::timeout(Duration::from_secs(10), a_disconnected.recv()).await.unwrap();
+ tokio::time::timeout(Duration::from_secs(1), b_disconnected.recv()).await.unwrap();
+ assert!(a_handler.disconnected_flag.load(Ordering::SeqCst));
+ assert!(b_handler.disconnected_flag.load(Ordering::SeqCst));
+
+ fut_a.await;
+ fut_b.await;
+ }
+
+ #[tokio::test(flavor = "multi_thread")]
+ async fn basic_threaded_connection_test() {
+ do_basic_connection_test().await;
+ }
+
+ #[tokio::test]
+ async fn basic_unthreaded_connection_test() {
+ do_basic_connection_test().await;
+ }
+
+ async fn race_disconnect_accept() {
+ // Previously, if we handed an already-disconnected socket to `setup_inbound` we'd panic.
+ // This attempts to find other similar races by opening connections and shutting them down
+ // while connecting. Sadly in testing this did *not* reproduce the previous issue.
+ let secp_ctx = Secp256k1::new();
+ let a_key = SecretKey::from_slice(&[1; 32]).unwrap();
+ let b_key = SecretKey::from_slice(&[2; 32]).unwrap();
+ let b_pub = PublicKey::from_secret_key(&secp_ctx, &b_key);
+
+ let a_manager = Arc::new(PeerManager::new(MessageHandler {
+ chan_handler: Arc::new(lightning::ln::peer_handler::ErroringMessageHandler::new()),
+ onion_message_handler: Arc::new(lightning::ln::peer_handler::IgnoringMessageHandler{}),
+ route_handler: Arc::new(lightning::ln::peer_handler::IgnoringMessageHandler{}),
+ custom_message_handler: Arc::new(lightning::ln::peer_handler::IgnoringMessageHandler{}),
+ }, 0, &[1; 32], Arc::new(TestLogger()), Arc::new(TestNodeSigner::new(a_key))));
+
+ // Make two connections, one for an inbound and one for an outbound connection
+ let conn_a = {
+ let (conn_a, _) = make_tcp_connection();
+ conn_a
+ };
+ let conn_b = {
+ let (_, conn_b) = make_tcp_connection();
+ conn_b
+ };
+
+ // Call connection setup inside new tokio tasks.
+ let manager_reference = Arc::clone(&a_manager);
+ tokio::spawn(async move {
+ super::setup_inbound(manager_reference, conn_a).await
+ });
+ tokio::spawn(async move {
+ super::setup_outbound(a_manager, b_pub, conn_b).await
+ });
+ }
+
+ #[tokio::test(flavor = "multi_thread")]
+ async fn threaded_race_disconnect_accept() {
+ race_disconnect_accept().await;
+ }
+
+ #[tokio::test]
+ async fn unthreaded_race_disconnect_accept() {
+ race_disconnect_accept().await;
+ }
+}