use crate::endpoint::RelayEndpoint;
use pb_mapper_core::{checksum::Credential, config::control_io_timeout};
use pb_mapper_protocol::{
MessageReader, MessageWriter,
command::{MessageSerializer, PbConnRequest, PbConnResponse},
direct::*,
secure::ClientHeaderSession,
};
use std::{
collections::HashMap,
io,
sync::{
Arc, Mutex,
atomic::{AtomicBool, AtomicU64, Ordering},
},
time::Duration,
};
use tokio::sync::{mpsc, oneshot};
type GrantReply = oneshot::Sender<io::Result<Option<SessionGrant>>>;
struct Pending {
opens: HashMap<u64, GrantReply>,
relays: HashMap<SessionId, oneshot::Sender<io::Result<()>>>,
}
pub(super) struct Control {
tx: mpsc::Sender<DirectClientMessage>,
pending: Arc<Mutex<Pending>>,
next: AtomicU64,
alive: Arc<AtomicBool>,
task: tokio_util::task::AbortOnDropHandle<()>,
pub capability: DirectCapability,
}
impl Control {
pub fn alive(&self) -> bool {
self.alive.load(Ordering::Acquire) && !self.task.is_finished()
}
pub async fn connect(
remote: &RelayEndpoint,
credential: Credential,
namespace: Option<u64>,
) -> io::Result<Arc<Self>> {
let mut socket = remote.connect().await?;
let relay_ip = socket.peer_addr()?.ip();
let session = ClientHeaderSession::new_v2(&credential).map_err(io_error)?;
session
.write_initial(
&mut socket,
&PbConnRequest::DirectControl { namespace }
.encode()
.map_err(io_error)?,
)
.await
.map_err(io_error)?;
let (tx, mut rx) = mpsc::channel::<DirectClientMessage>(64);
let pending = Arc::new(Mutex::new(Pending {
opens: HashMap::new(),
relays: HashMap::new(),
}));
let alive = Arc::new(AtomicBool::new(true));
let (ready, ready_rx) = oneshot::channel();
let pending_task = pending.clone();
let alive_task = alive.clone();
let task = tokio_util::task::AbortOnDropHandle::new(tokio::spawn(async move {
let cleanup = ControlCleanup {
pending: pending_task.clone(),
alive: alive_task,
};
let result: io::Result<()> = async {
let (mut read, mut write) = socket.into_split();
let mut reader = session.response_reader(&mut read).map_err(io_error)?;
let mut writer = session.continuation_writer(&mut write).map_err(io_error)?;
let first = PbConnResponse::decode(reader.read_msg().await.map_err(io_error)?).map_err(io_error)?;
let PbConnResponse::Direct(DirectEvent::Ready(capability)) = first else { return Err(io::Error::other("relay declined direct control")); };
let _ = ready.send(capability);
let reading = async {
loop {
let bytes = tokio::time::timeout(Duration::from_secs(45), reader.read_msg()).await.map_err(|_|io::Error::other("direct control idle"))?.map_err(io_error)?;
let response = PbConnResponse::decode(bytes).map_err(io_error)?;
let PbConnResponse::Direct(event) = response else { return Err(io::Error::other("unexpected direct control response")); };
let mut pending = pending_task.lock().unwrap_or_else(|e| e.into_inner());
match event {
DirectEvent::Granted { request, grant } => { if let Some(reply) = pending.opens.remove(&request) { let _ = reply.send(Ok(Some(grant))); } }
DirectEvent::LegacyRelay { request } => { if let Some(reply) = pending.opens.remove(&request) { let _ = reply.send(Ok(None)); } }
DirectEvent::Rejected { request, reason } => { if let Some(reply) = pending.opens.remove(&request) { let _ = reply.send(Err(io::Error::other(reason))); } }
DirectEvent::RelaySelected { id } => { if let Some(reply) = pending.relays.remove(&id) { let _ = reply.send(Ok(())); } }
DirectEvent::Pong => {}
_ => return Err(io::Error::other("invalid consumer coordination event")),
}
}
};
let writing = async {
let mut ping = tokio::time::interval(Duration::from_secs(15));
loop {
let message = tokio::select! {
message = rx.recv() => { let Some(message) = message else { return Ok(()); }; message },
_ = ping.tick() => DirectClientMessage::Ping,
};
let bytes = message.encode().map_err(io_error)?;
tokio::time::timeout(Duration::from_secs(5), writer.write_msg(&bytes)).await.map_err(|_|io::Error::other("direct control write timeout"))?.map_err(io_error)?;
}
};
tokio::select! { result = reading => result, result = writing => result }
}.await;
if let Err(error) = result {
tracing::debug!(%error, "direct coordination disconnected; established data sessions stay alive");
}
drop(cleanup);
}));
let mut capability = tokio::time::timeout(control_io_timeout(), ready_rx)
.await
.map_err(|_| io::Error::new(io::ErrorKind::TimedOut, "direct control not ready"))?
.map_err(|_| io::Error::other("direct control closed before ready"))?;
capability.stun_addr = stun_target(capability.stun_addr, relay_ip);
Ok(Arc::new(Self {
tx,
pending,
next: AtomicU64::new(1),
alive,
task,
capability,
}))
}
pub async fn open(
&self,
key: String,
is_datagram: bool,
peer: PeerInfo,
) -> io::Result<Option<SessionGrant>> {
let request = self.next.fetch_add(1, Ordering::Relaxed);
let (tx, rx) = oneshot::channel();
{
let mut pending = self.pending.lock().unwrap_or_else(|e| e.into_inner());
pending.opens.retain(|_, reply| !reply.is_closed());
if pending.opens.len() >= 64 {
return Err(io::Error::other("direct setup capacity reached"));
}
pending.opens.insert(request, tx);
}
let _guard = PendingGuard {
pending: self.pending.clone(),
tx: self.tx.clone(),
request: Some(request),
id: None,
};
self.tx
.send(DirectClientMessage::Open {
request,
key,
is_datagram,
peer,
})
.await
.map_err(|_| io::Error::other("direct control closed"))?;
rx.await
.map_err(|_| io::Error::other("direct grant lost"))?
}
pub async fn relay(&self, id: SessionId) -> io::Result<()> {
let (tx, rx) = oneshot::channel();
self.pending
.lock()
.unwrap_or_else(|e| e.into_inner())
.relays
.insert(id, tx);
let _guard = PendingGuard {
pending: self.pending.clone(),
tx: self.tx.clone(),
request: None,
id: Some(id),
};
self.tx
.send(DirectClientMessage::RelaySelect { id })
.await
.map_err(|_| io::Error::other("direct control closed"))?;
rx.await
.map_err(|_| io::Error::other("relay selection lost"))?
}
pub async fn report(&self, report: SessionUpdate) -> io::Result<()> {
self.tx
.send(DirectClientMessage::Report(report))
.await
.map_err(|_| io::Error::other("direct control closed"))
}
pub fn cancel(&self, id: SessionId) {
let _ = self.tx.try_send(DirectClientMessage::Cancel { id });
}
}
struct PendingGuard {
tx: mpsc::Sender<DirectClientMessage>,
pending: Arc<Mutex<Pending>>,
request: Option<u64>,
id: Option<SessionId>,
}
impl Drop for PendingGuard {
fn drop(&mut self) {
let mut p = self.pending.lock().unwrap_or_else(|e| e.into_inner());
if let Some(r) = self.request
&& p.opens.remove(&r).is_some()
{
let _ = self
.tx
.try_send(DirectClientMessage::CancelOpen { request: r });
}
if let Some(id) = self.id {
p.relays.remove(&id);
}
}
}
struct ControlCleanup {
pending: Arc<Mutex<Pending>>,
alive: Arc<AtomicBool>,
}
impl Drop for ControlCleanup {
fn drop(&mut self) {
self.alive.store(false, Ordering::Release);
let mut p = self.pending.lock().unwrap_or_else(|e| e.into_inner());
p.opens.clear();
p.relays.clear();
}
}
pub(super) fn io_error(error: impl std::fmt::Display) -> io::Error {
io::Error::other(error.to_string())
}