1use crate::engine::EngineRequest;
7use crate::event::Event;
8use crate::message::{Capabilities, ClientMessage, ErrorResponse, Message, ServerMessage};
9use argon2::{Argon2, PasswordVerifier, password_hash::PasswordHashString};
10use rustls::ServerConfig;
11use rustls::pki_types::{
12 CertificateDer, PrivateKeyDer,
13 pem::{self, PemObject},
14};
15use std::collections::HashMap;
16use std::fmt::Debug;
17use std::net::{IpAddr, SocketAddr};
18use std::path::PathBuf;
19use std::result;
20use std::sync::Arc;
21use std::time::Duration;
22use thiserror::Error;
23use tokio::io::{self, AsyncRead, AsyncReadExt, AsyncWrite, AsyncWriteExt, BufReader, BufWriter};
24use tokio::net::{TcpListener, TcpStream};
25use tokio::sync::{RwLock, broadcast, mpsc, oneshot};
26use tokio::time::timeout;
27#[cfg(feature = "tokio-graceful-shutdown")]
28use tokio_graceful_shutdown::{FutureExt, IntoSubsystem, SubsystemHandle};
29use tokio_rustls::TlsAcceptor;
30use tracing::{info, instrument, warn};
31
32pub type ClientRegistry = HashMap<String, PasswordHashString>;
36
37#[derive(Error, Debug)]
38pub enum Error {
39 #[error(transparent)]
40 Io(#[from] io::Error),
41
42 #[error(transparent)]
43 Oneshot(#[from] oneshot::error::RecvError),
44
45 #[error("client sent unexpected message: {0:?}")]
46 UnexpectedMessage(ClientMessage),
47
48 #[error("client requested an unsupported version range: {0} - {1}")]
49 UnsupportedVersion(u8, u8),
50
51 #[error("unrecognized request code: {0}")]
52 UnknownRequest(u8),
53
54 #[error("client provided invalid credentials")]
55 InvalidCredentials,
56}
57
58pub type Result<T> = result::Result<T, Error>;
59
60#[derive(Debug)]
63#[allow(dead_code)]
64pub struct CustomRequestMessage {
65 client_id: String,
66 message: Message,
67 response: oneshot::Sender<Option<Message>>,
68}
69
70pub struct NetworkListener {
103 clients: Arc<RwLock<ClientRegistry>>,
104 addr: SocketAddr,
105 tls_acceptor: TlsAcceptor,
106 engine_tx: mpsc::Sender<(EngineRequest, oneshot::Sender<ServerMessage>)>,
107 event_tx: broadcast::Sender<Event>,
108 custom_req_tx: Option<mpsc::Sender<CustomRequestMessage>>,
109}
110
111impl Debug for NetworkListener {
112 fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
113 f.debug_struct("NetworkListener")
114 .field("clients", &self.clients)
115 .field("addr", &self.addr)
116 .field("engine_tx", &self.engine_tx)
117 .field("event_tx", &self.event_tx)
118 .field("custom_req_tx", &self.custom_req_tx)
119 .finish()
120 }
121}
122
123impl NetworkListener {
124 pub async fn listen(&self) -> Result<()> {
131 let listener = TcpListener::bind(self.addr).await?;
132 let mut con_counter: usize = 0;
133
134 loop {
135 let (stream, peer_addr) = listener.accept().await?;
136 let conn_id = con_counter;
137 con_counter += 1;
138 let event_tx = self.event_tx.clone();
139
140 self.handle_stream(stream, peer_addr, self.clients.clone(), conn_id, event_tx);
141 }
142 }
143
144 #[instrument(skip(self, stream, peer_addr, clients, event_tx))]
145 fn handle_stream(
146 &self,
147 stream: TcpStream,
148 peer_addr: SocketAddr,
149 clients: Arc<RwLock<ClientRegistry>>,
150 conn_id: usize,
151 event_tx: broadcast::Sender<Event>,
152 ) {
153 let acceptor = self.tls_acceptor.clone();
154 let engine_tx = self.engine_tx.clone();
155 let custom_req_tx = self.custom_req_tx.clone();
156
157 tokio::spawn(async move {
158 info!("new connection from {}", peer_addr);
159
160 let stream = match acceptor.accept(stream).await {
161 Ok(stream) => stream,
162 Err(error) => {
163 warn!("failed to accept stream: {}", error);
164 return;
165 }
166 };
167
168 let (reader, writer) = io::split(stream);
169 let mut reader = BufReader::new(reader);
170 let mut writer = BufWriter::new(writer);
171
172 let (client_id, local_ip, _version) = match timeout(
173 Duration::from_secs(2),
174 authenticate(&mut reader, &mut writer, clients),
175 )
176 .await
177 {
178 Ok(Ok(result)) => result,
179 Ok(Err(Error::UnexpectedMessage(message))) => {
180 warn!("client error: unexpected message: {:?}", message);
181 let _ = write_to_stream(
182 &mut writer,
183 ServerMessage::Error(ErrorResponse::UnexpectedMessage),
184 )
185 .await;
186 return;
187 }
188 Ok(Err(Error::UnsupportedVersion(min_version, max_version))) => {
189 warn!("client error: unsupported version range: {min_version} - {max_version}");
190 let _ = write_to_stream(
191 &mut writer,
192 ServerMessage::Error(ErrorResponse::UnsupportedVersionRange),
193 )
194 .await;
195 return;
196 }
197 Ok(Err(Error::InvalidCredentials)) => {
198 warn!("client error: invalid credentials");
199 let _ = write_to_stream(
200 &mut writer,
201 ServerMessage::Error(ErrorResponse::InvalidCredentials),
202 )
203 .await;
204 return;
205 }
206 Ok(Err(Error::Io(error)))
207 if matches!(
208 error.kind(),
209 io::ErrorKind::InvalidInput | io::ErrorKind::InvalidData
210 ) =>
211 {
212 warn!("client error: malformed message: {:?}", error);
213 let _ = write_to_stream(
214 &mut writer,
215 ServerMessage::Error(ErrorResponse::MalformedMessage),
216 )
217 .await;
218 return;
219 }
220 Ok(Err(error)) => {
221 warn!("client error: connection died: {:?}", error);
222 return;
223 }
224 Err(_) => {
225 warn!("client error: authentication timed out");
226 return;
227 }
228 };
229
230 let _ = event_tx.send(Event::ClientConnect {
231 client_id: client_id.clone(),
232 conn_id,
233 local_ip,
234 });
235
236 match handle_connection(
237 &mut reader,
238 &mut writer,
239 &client_id,
240 engine_tx,
241 custom_req_tx,
242 )
243 .await
244 {
245 Ok(()) => {
246 let _ = event_tx.send(Event::ClientDisconnect { client_id, conn_id });
247 return;
248 }
249 Err(Error::UnexpectedMessage(message)) => {
250 warn!("client error: unexpected message: {:?}", message);
251 let _ = write_to_stream(
252 &mut writer,
253 ServerMessage::Error(ErrorResponse::UnexpectedMessage),
254 )
255 .await;
256 }
257 Err(Error::Io(error))
258 if matches!(
259 error.kind(),
260 io::ErrorKind::InvalidInput | io::ErrorKind::InvalidData
261 ) =>
262 {
263 warn!("client error: malformed message: {:?}", error);
264 let _ = write_to_stream(
265 &mut writer,
266 ServerMessage::Error(ErrorResponse::MalformedMessage),
267 )
268 .await;
269 return;
270 }
271 Err(error) => {
272 warn!("client error: connection died: {:?}", error);
273 return;
274 }
275 }
276
277 let _ = event_tx.send(Event::ClientConnectionLoss { client_id, conn_id });
278 });
279 }
280}
281
282#[cfg(feature = "tokio-graceful-shutdown")]
283impl IntoSubsystem<Error> for NetworkListener {
284 async fn run(self, subsys: &mut SubsystemHandle) -> Result<()> {
285 if let Ok(result) = self.listen().cancel_on_shutdown(subsys).await {
286 result?
287 }
288
289 Ok(())
290 }
291}
292
293async fn read_from_stream<S: AsyncRead + Unpin + Send>(stream: &mut S) -> Result<ClientMessage> {
294 let message_type = stream.read_u8().await?;
295 let payload_length = stream.read_u32_le().await?;
296
297 if payload_length == 0 {
298 return Ok(Message::new(message_type, vec![]).try_into()?);
299 }
300
301 let mut message = vec![0; payload_length as usize];
302 stream.read_exact(&mut message).await?;
303
304 Ok(Message::new(message_type, message).try_into()?)
305}
306
307async fn write_to_stream<S: AsyncWrite + Unpin + Send>(
308 stream: &mut S,
309 message: impl Into<Message>,
310) -> Result<()> {
311 let message: Message = message.into();
312 stream.write_all(&message.into_bytes()).await?;
313 stream.flush().await?;
314
315 Ok(())
316}
317
318#[derive(Debug, Error)]
319pub enum BuilderError {
320 #[error("missing field: {0}")]
321 MissingField(&'static str),
322
323 #[error(transparent)]
324 AddrParse(#[from] std::net::AddrParseError),
325
326 #[error("failed to read PEM file at {path}: {source}")]
327 Pem {
328 path: PathBuf,
329 #[source]
330 source: pem::Error,
331 },
332
333 #[error(transparent)]
334 Rustls(#[from] rustls::Error),
335}
336
337pub type BuilderResult<T> = result::Result<T, BuilderError>;
338
339#[derive(Debug, Default)]
366pub struct NetworkListenerBuilder {
367 address: Option<String>,
368 cert_path: Option<PathBuf>,
369 key_path: Option<PathBuf>,
370 clients: Option<Arc<RwLock<ClientRegistry>>>,
371 engine_tx: Option<mpsc::Sender<(EngineRequest, oneshot::Sender<ServerMessage>)>>,
372 event_tx: Option<broadcast::Sender<Event>>,
373 custom_req_tx: Option<mpsc::Sender<CustomRequestMessage>>,
374}
375
376impl NetworkListenerBuilder {
377 pub fn new() -> Self {
378 Self {
379 address: None,
380 cert_path: None,
381 key_path: None,
382 clients: None,
383 engine_tx: None,
384 event_tx: None,
385 custom_req_tx: None,
386 }
387 }
388
389 pub fn custom_req_tx(
390 self,
391 custom_req_tx: mpsc::Sender<CustomRequestMessage>,
392 ) -> NetworkListenerBuilder {
393 NetworkListenerBuilder {
394 clients: self.clients,
395 address: self.address,
396 cert_path: self.cert_path,
397 key_path: self.key_path,
398 engine_tx: self.engine_tx,
399 event_tx: self.event_tx,
400 custom_req_tx: Some(custom_req_tx),
401 }
402 }
403
404 pub fn address(mut self, address: impl Into<String>) -> Self {
405 self.address = Some(address.into());
406 self
407 }
408
409 pub fn cert_path(mut self, path: impl Into<PathBuf>) -> Self {
410 self.cert_path = Some(path.into());
411 self
412 }
413
414 pub fn key_path(mut self, path: impl Into<PathBuf>) -> Self {
415 self.key_path = Some(path.into());
416 self
417 }
418
419 pub fn clients(mut self, clients: Arc<RwLock<ClientRegistry>>) -> Self {
420 self.clients = Some(clients);
421 self
422 }
423
424 pub fn engine_tx(
425 mut self,
426 tx: mpsc::Sender<(EngineRequest, oneshot::Sender<ServerMessage>)>,
427 ) -> Self {
428 self.engine_tx = Some(tx);
429 self
430 }
431
432 pub fn event_tx(mut self, tx: broadcast::Sender<Event>) -> Self {
433 self.event_tx = Some(tx);
434 self
435 }
436
437 pub fn build(self) -> BuilderResult<NetworkListener> {
441 let addr: SocketAddr = self
442 .address
443 .ok_or_else(|| BuilderError::MissingField("address"))?
444 .parse()?;
445
446 let cert_path = self
447 .cert_path
448 .ok_or_else(|| BuilderError::MissingField("cert_path"))?;
449 let key_path = self
450 .key_path
451 .ok_or_else(|| BuilderError::MissingField("key_path"))?;
452
453 let certs = CertificateDer::pem_file_iter(&cert_path)
454 .map_err(|err| BuilderError::Pem {
455 path: cert_path.clone(),
456 source: err,
457 })?
458 .collect::<result::Result<Vec<_>, _>>()
459 .map_err(|err| BuilderError::Pem {
460 path: cert_path,
461 source: err,
462 })?;
463 let key = PrivateKeyDer::from_pem_file(&key_path).map_err(|err| BuilderError::Pem {
464 path: key_path,
465 source: err,
466 })?;
467
468 let config = ServerConfig::builder()
469 .with_no_client_auth()
470 .with_single_cert(certs, key)?;
471 let tls_acceptor = TlsAcceptor::from(Arc::new(config));
472
473 Ok(NetworkListener {
474 clients: self
475 .clients
476 .ok_or_else(|| BuilderError::MissingField("clients"))?,
477 addr,
478 tls_acceptor,
479 engine_tx: self
480 .engine_tx
481 .ok_or_else(|| BuilderError::MissingField("engine_tx"))?,
482 event_tx: self
483 .event_tx
484 .ok_or_else(|| BuilderError::MissingField("event_tx"))?,
485 custom_req_tx: self.custom_req_tx,
486 })
487 }
488}
489
490async fn handle_connection<R, W>(
495 reader: &mut R,
496 writer: &mut W,
497 client_id: &str,
498 engine_tx: mpsc::Sender<(EngineRequest, oneshot::Sender<ServerMessage>)>,
499 custom_req_tx: Option<mpsc::Sender<CustomRequestMessage>>,
500) -> Result<()>
501where
502 R: AsyncRead + Unpin + Send,
503 W: AsyncWrite + Unpin + Send,
504{
505 loop {
506 let message = match timeout(Duration::from_secs(30), read_from_stream(reader)).await {
507 Ok(Ok(message)) => message,
508 Ok(Err(error)) => return Err(error),
509 Err(_) => return Ok(()),
510 };
511
512 let engine_request = match message {
513 ClientMessage::Bloop { nfc_uid } => EngineRequest::Bloop {
514 nfc_uid,
515 client_id: client_id.to_string(),
516 },
517 ClientMessage::RetrieveAudio { achievement_id } => {
518 EngineRequest::RetrieveAudio { id: achievement_id }
519 }
520 ClientMessage::PreloadCheck {
521 audio_manifest_hash,
522 } => EngineRequest::PreloadCheck {
523 manifest_hash: audio_manifest_hash,
524 },
525 ClientMessage::Ping => {
526 write_to_stream(writer, ServerMessage::Pong).await?;
527 continue;
528 }
529 ClientMessage::Quit => break,
530 ClientMessage::Unknown(message) => {
531 if let Some(sender) = custom_req_tx.as_ref() {
532 let (resp_tx, resp_rx) = oneshot::channel();
533
534 let _ = sender
535 .send(CustomRequestMessage {
536 client_id: client_id.to_string(),
537 message,
538 response: resp_tx,
539 })
540 .await;
541
542 if let Some(message) = resp_rx.await? {
543 write_to_stream(writer, message).await?;
544 }
545 }
546
547 continue;
548 }
549 message => return Err(Error::UnexpectedMessage(message)),
550 };
551
552 let (resp_tx, resp_rx) = oneshot::channel();
553 let _ = engine_tx.send((engine_request, resp_tx)).await;
554 let response = resp_rx.await?;
555
556 write_to_stream(writer, response).await?;
557 }
558
559 Ok(())
560}
561
562async fn authenticate<R, W>(
567 reader: &mut R,
568 writer: &mut W,
569 clients: Arc<RwLock<ClientRegistry>>,
570) -> Result<(String, IpAddr, u8)>
571where
572 R: AsyncRead + Unpin + Send,
573 W: AsyncWrite + Unpin + Send,
574{
575 let (min_version, max_version) = match read_from_stream(reader).await? {
576 ClientMessage::ClientHandshake {
577 min_version,
578 max_version,
579 } => (min_version, max_version),
580 message => return Err(Error::UnexpectedMessage(message)),
581 };
582
583 if min_version > 3 || max_version < 3 {
584 return Err(Error::UnsupportedVersion(min_version, max_version));
585 }
586
587 write_to_stream(
588 writer,
589 ServerMessage::ServerHandshake {
590 accepted_version: 3,
591 capabilities: Capabilities::PreloadCheck,
592 },
593 )
594 .await?;
595
596 let (client_id, client_secret, ip_addr) = match read_from_stream(reader).await? {
597 ClientMessage::Authentication {
598 client_id,
599 client_secret,
600 ip_addr,
601 } => (client_id, client_secret, ip_addr),
602 message => return Err(Error::UnexpectedMessage(message)),
603 };
604
605 let clients = clients.read().await;
606 let Some(secret_hash) = clients.get(&client_id) else {
607 return Err(Error::InvalidCredentials);
608 };
609
610 if Argon2::default()
611 .verify_password(client_secret.as_bytes(), &secret_hash.password_hash())
612 .is_err()
613 {
614 return Err(Error::InvalidCredentials);
615 }
616
617 write_to_stream(writer, ServerMessage::AuthenticationAccepted).await?;
618
619 Ok((client_id.to_string(), ip_addr, 3))
620}
621
622#[cfg(test)]
623mod tests {
624 use super::*;
625 use std::fs;
626 use tempfile::tempdir;
627
628 #[tokio::test]
629 async fn builder_fails_with_missing_fields() {
630 let builder = NetworkListenerBuilder::new();
631 let result = builder.build();
632 assert!(matches!(result, Err(BuilderError::MissingField(_))));
633 }
634
635 #[tokio::test]
636 async fn builder_fails_with_invalid_address() {
637 let builder = NetworkListenerBuilder::new()
638 .address("invalid-addr")
639 .cert_path("cert.pem")
640 .key_path("key.pem")
641 .clients(Arc::new(RwLock::new(Default::default())))
642 .engine_tx(dummy_engine_tx())
643 .event_tx(dummy_event_tx());
644
645 let result = builder.build();
646 assert!(matches!(result, Err(BuilderError::AddrParse(_))));
647 }
648
649 #[tokio::test]
650 async fn builder_fails_on_invalid_pem_files() {
651 let dir = tempdir().unwrap();
652 let cert_path = dir.path().join("cert.pem");
653 let key_path = dir.path().join("key.pem");
654 fs::write(&cert_path, b"invalid-cert").unwrap();
655 fs::write(&key_path, b"invalid-key").unwrap();
656
657 let builder = NetworkListenerBuilder::new()
658 .address("127.0.0.1:12345")
659 .cert_path(&cert_path)
660 .key_path(&key_path)
661 .clients(Arc::new(RwLock::new(Default::default())))
662 .engine_tx(dummy_engine_tx())
663 .event_tx(dummy_event_tx());
664
665 let result = builder.build();
666 assert!(matches!(result, Err(BuilderError::Pem { .. })));
667 }
668
669 #[tokio::test]
670 async fn builder_succeeds_with_valid_dummy_pem() {
671 let dir = tempdir().unwrap();
672 let cert_path = dir.path().join("cert.pem");
673 let key_path = dir.path().join("key.pem");
674
675 let cert_data = include_bytes!("../examples/cert.pem");
676 let key_data = include_bytes!("../examples/key.pem");
677
678 fs::write(&cert_path, cert_data).unwrap();
679 fs::write(&key_path, key_data).unwrap();
680
681 let builder = NetworkListenerBuilder::new()
682 .address("127.0.0.1:12345")
683 .cert_path(&cert_path)
684 .key_path(&key_path)
685 .clients(Arc::new(RwLock::new(Default::default())))
686 .engine_tx(dummy_engine_tx())
687 .event_tx(dummy_event_tx());
688
689 let result = builder.build();
690 assert!(result.is_ok());
691 }
692
693 #[tokio::test]
694 async fn authentication_fails_with_wrong_client_id() {
695 let clients = Arc::new(RwLock::new(Default::default()));
696
697 let client_handshake = build_handshake(3, 3);
698 let authentication = build_authentication("unknown-client", "password", "127.0.0.1");
699
700 let server_handshake: Message = ServerMessage::ServerHandshake {
701 accepted_version: 3,
702 capabilities: Capabilities::PreloadCheck,
703 }
704 .into();
705
706 let mut reader = tokio_test::io::Builder::new()
707 .read(&client_handshake)
708 .read(&authentication)
709 .build();
710 let mut writer = tokio_test::io::Builder::new()
711 .write(&server_handshake.into_bytes())
712 .build();
713
714 let result = authenticate(&mut reader, &mut writer, clients).await;
715
716 assert!(matches!(result, Err(Error::InvalidCredentials)));
717 }
718
719 #[tokio::test]
720 async fn authentication_succeeds_with_correct_credentials() {
721 let clients = Arc::new(RwLock::new(HashMap::default()));
722 clients.write().await.insert(
723 "client".into(),
724 PasswordHashString::new(
725 "$argon2id$v=19$m=10,t=1,p=1$THh0RHE5YWNkQUZNa2lqUA$dmB4X7J49jjCGA",
726 )
727 .unwrap(),
728 );
729
730 let client_handshake = build_handshake(3, 3);
731 let authentication = build_authentication("client", "secret", "127.0.0.1");
732
733 let server_handshake: Message = ServerMessage::ServerHandshake {
734 accepted_version: 3,
735 capabilities: Capabilities::PreloadCheck,
736 }
737 .into();
738
739 let authentication_accepted: Message = ServerMessage::AuthenticationAccepted.into();
740
741 let mut reader = tokio_test::io::Builder::new()
742 .read(&client_handshake)
743 .read(&authentication)
744 .build();
745 let mut writer = tokio_test::io::Builder::new()
746 .write(&server_handshake.into_bytes())
747 .write(&authentication_accepted.into_bytes())
748 .build();
749
750 let result = authenticate(&mut reader, &mut writer, clients).await;
751 println!("{:?}", result);
752
753 assert!(result.is_ok());
754 }
755
756 #[tokio::test]
757 async fn authentication_fails_with_wrong_password() {
758 let clients = Arc::new(RwLock::new(HashMap::default()));
759 clients.write().await.insert(
760 "client".into(),
761 PasswordHashString::new(
762 "$argon2id$v=19$m=10,t=1,p=1$THh0RHE5YWNkQUZNa2lqUA$dmB4X7J49jjCGA",
763 )
764 .unwrap(),
765 );
766
767 let client_handshake = build_handshake(3, 3);
768 let authentication = build_authentication("client1", "wrong-secret", "127.0.0.1");
769
770 let server_handshake: Message = ServerMessage::ServerHandshake {
771 accepted_version: 3,
772 capabilities: Capabilities::PreloadCheck,
773 }
774 .into();
775
776 let mut reader = tokio_test::io::Builder::new()
777 .read(&client_handshake)
778 .read(&authentication)
779 .build();
780 let mut writer = tokio_test::io::Builder::new()
781 .write(&server_handshake.into_bytes())
782 .build();
783
784 let result = authenticate(&mut reader, &mut writer, clients).await;
785
786 assert!(matches!(result, Err(Error::InvalidCredentials)));
787 }
788
789 fn dummy_engine_tx() -> mpsc::Sender<(EngineRequest, oneshot::Sender<ServerMessage>)> {
790 let (tx, _rx) = mpsc::channel(1);
791 tx
792 }
793
794 fn dummy_event_tx() -> broadcast::Sender<Event> {
795 let (tx, _rx) = broadcast::channel(1);
796 tx
797 }
798
799 fn build_handshake(min_version: u8, max_version: u8) -> Vec<u8> {
800 let mut buf = Vec::new();
801 let payload = [min_version, max_version];
802
803 buf.push(0x01);
804 buf.extend(&(payload.len() as u32).to_le_bytes());
805 buf.extend(&payload);
806
807 buf
808 }
809
810 fn build_authentication(client_id: &str, password: &str, ip_addr: &str) -> Vec<u8> {
811 use std::net::IpAddr;
812
813 let mut buf = Vec::new();
814
815 let client_id_bytes = client_id.as_bytes();
816 let password_bytes = password.as_bytes();
817
818 let mut payload = Vec::new();
819 payload.push(client_id_bytes.len() as u8);
820 payload.extend(client_id_bytes);
821
822 payload.push(password_bytes.len() as u8);
823 payload.extend(password_bytes);
824
825 let ip: IpAddr = ip_addr.parse().expect("Invalid IP address");
826 match ip {
827 IpAddr::V4(v4) => {
828 payload.push(4); payload.extend(&v4.octets());
830 }
831 IpAddr::V6(v6) => {
832 payload.push(6); payload.extend(&v6.octets());
834 }
835 }
836
837 buf.push(0x03);
838 buf.extend(&(payload.len() as u32).to_le_bytes());
839 buf.extend(payload);
840
841 buf
842 }
843}