Expose TLS error to Subscribers using on_tls_handshake_failed (#2855)

Author: Mark-Simulacrum

dc/s2n-quic-dc/src/stream/recv/error.rs

@@ -37,7 +37,7 @@ impl fmt::Display for Error {
     }
 }
 
-impl std::error::Error for Error {}
+impl core::error::Error for Error {}
 
 impl IntoEvent<Error> for Error {
     fn into_event(self) -> Error {

dc/s2n-quic-dc/src/stream/send/error.rs

@@ -34,7 +34,7 @@ impl fmt::Display for Error {
     }
 }
 
-impl std::error::Error for Error {}
+impl core::error::Error for Error {}
 
 impl IntoEvent<Error> for Error {
     fn into_event(self) -> Error {

quic/s2n-quic-core/events/connection.rs

@@ -345,6 +345,7 @@ struct TlsExporterReady<'a> {
 #[event("connectivity:tls_handshake_failed")]
 struct TlsHandshakeFailed<'a> {
     session: crate::event::TlsSession<'a>,
+    error: &'a (dyn core::error::Error + Send + Sync + 'static),
 }
 
 #[event("connectivity:path_challenge_updated")]

quic/s2n-quic-core/src/application/error.rs

@@ -18,8 +18,7 @@ use core::{fmt, ops};
 #[derive(Copy, Clone, Eq, PartialEq)]
 pub struct Error(VarInt);
 
-#[cfg(feature = "std")]
-impl std::error::Error for Error {}
+impl core::error::Error for Error {}
 
 impl fmt::Debug for Error {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {

quic/s2n-quic-core/src/buffer/deque.rs

@@ -225,8 +225,7 @@ impl fmt::Display for FillError {
     }
 }
 
-#[cfg(feature = "std")]
-impl std::error::Error for FillError {}
+impl core::error::Error for FillError {}
 
 #[cfg(feature = "std")]
 impl From<FillError> for std::io::Error {

quic/s2n-quic-core/src/connection/error.rs

@@ -101,8 +101,7 @@ pub enum Error {
     },
 }
 
-#[cfg(feature = "std")]
-impl std::error::Error for Error {}
+impl core::error::Error for Error {}
 
 impl fmt::Display for Error {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {

quic/s2n-quic-core/src/crypto/tls.rs

@@ -166,6 +166,7 @@ pub trait Context<Crypto: crate::crypto::CryptoSuite> {
     fn on_tls_handshake_failed(
         &mut self,
         session: &impl TlsSession,
+        error: &(dyn core::error::Error + Send + Sync + 'static),
     ) -> Result<(), crate::transport::Error>;
 
     /// Receives data from the initial packet space

quic/s2n-quic-core/src/crypto/tls/offload.rs

@@ -21,7 +21,11 @@ pub trait Executor {
 
 /// Allows access to the TlsSession on handshake failure and when the exporter secret is ready.
 pub trait ExporterHandler {
-    fn on_tls_handshake_failed(&self, session: &impl TlsSession) -> Option<Box<dyn Any + Send>>;
+    fn on_tls_handshake_failed(
+        &self,
+        session: &impl TlsSession,
+        e: &(dyn core::error::Error + Send + Sync + 'static),
+    ) -> Option<Box<dyn Any + Send>>;
     fn on_tls_exporter_ready(&self, session: &impl TlsSession) -> Option<Box<dyn Any + Send>>;
 }
 
@@ -30,6 +34,7 @@ impl ExporterHandler for () {
     fn on_tls_handshake_failed(
         &self,
         _session: &impl TlsSession,
+        _e: &(dyn core::error::Error + Send + Sync + 'static),
     ) -> Option<Box<dyn std::any::Any + Send>> {
         None
     }
@@ -559,8 +564,9 @@ impl<S: CryptoSuite, H: ExporterHandler> tls::Context<S> for RemoteContext<'_, R
     fn on_tls_handshake_failed(
         &mut self,
         session: &impl tls::TlsSession,
+        e: &(dyn core::error::Error + Send + Sync + 'static),
     ) -> Result<(), crate::transport::Error> {
-        if let Some(context) = self.exporter_handler.on_tls_handshake_failed(session) {
+        if let Some(context) = self.exporter_handler.on_tls_handshake_failed(session, e) {
             match self.send_to_quic.push(Request::TlsContext(context)) {
                 Ok(_) => (),
                 Err(_) => self.error = Some(SLICE_ERROR),

quic/s2n-quic-core/src/crypto/tls/slow_tls.rs

@@ -167,8 +167,9 @@ where
     fn on_tls_handshake_failed(
         &mut self,
         session: &impl tls::TlsSession,
+        e: &(dyn core::error::Error + Send + Sync + 'static),
     ) -> Result<(), transport::Error> {
-        self.0.on_tls_exporter_ready(session)
+        self.0.on_tls_handshake_failed(session, e)
     }
 
     fn receive_initial(&mut self, max_len: Option<usize>) -> Option<tls::Bytes> {

quic/s2n-quic-core/src/crypto/tls/testing.rs

@@ -779,6 +779,7 @@ where
     fn on_tls_handshake_failed(
         &mut self,
         _: &impl super::TlsSession,
+        _: &(dyn std::error::Error + Send + Sync),
     ) -> Result<(), crate::transport::Error> {
         Ok(())
     }