Support exporting from TLS sessions

This also bumps s2n-tls dependency to 0.0.39 so that we can make use of
the new TLS-Exporter functionality in s2n-tls, not just in rustls.

examples/resumption/Cargo.toml

@@ -5,5 +5,5 @@ edition = "2021"
 
 [dependencies]
 s2n-quic = { version = "1", path = "../../quic/s2n-quic", features = ["provider-tls-s2n", "unstable_resumption"]}
-s2n-tls = { version = "=0.0.36", features = ["quic"] }
+s2n-tls = { version = "=0.0.39", features = ["quic"] }
 tokio = { version = "1", features = ["full"] }

netbench/netbench-driver/Cargo.toml

@@ -16,8 +16,8 @@ netbench = { version = "0.1", path = "../netbench" }
 probe = "0.5"
 s2n-quic = { path = "../../quic/s2n-quic", features = ["provider-tls-s2n"] }
 s2n-quic-core = { path = "../../quic/s2n-quic-core", features = ["testing"] }
-s2n-tls = { version = "0.0.36" }
-s2n-tls-tokio = { version = "0.0.36" }
+s2n-tls = { version = "0.0.39" }
+s2n-tls-tokio = { version = "0.0.39" }
 structopt = "0.3"
 tokio = { version = "1", features = ["io-util", "net", "time", "rt-multi-thread"] }
 tokio-native-tls = "0.3"

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

@@ -19,6 +19,29 @@ pub struct ApplicationParameters<'a> {
     pub transport_parameters: &'a [u8],
 }
 
+#[derive(Debug)]
+#[non_exhaustive]
+pub enum TlsExportError {
+    #[non_exhaustive]
+    Failure,
+}
+
+impl TlsExportError {
+    pub fn failure() -> Self {
+        TlsExportError::Failure
+    }
+}
+
+pub trait TlsSession: Send + Sync {
+    /// See <https://datatracker.ietf.org/doc/html/rfc5705> and <https://www.rfc-editor.org/rfc/rfc8446>.
+    fn tls_exporter(
+        &self,
+        label: &[u8],
+        context: &[u8],
+        output: &mut [u8],
+    ) -> Result<(), TlsExportError>;
+}
+
 //= https://www.rfc-editor.org/rfc/rfc9000#section-4
 //= type=TODO
 //= tracking-issue=332
@@ -64,6 +87,11 @@ pub trait Context<Crypto: crate::crypto::CryptoSuite> {
     //# peer's Finished message.
     fn on_handshake_complete(&mut self) -> Result<(), crate::transport::Error>;
 
+    fn on_tls_exporter_ready(
+        &mut self,
+        session: &impl TlsSession,
+    ) -> Result<(), crate::transport::Error>;
+
     /// Receives data from the initial packet space
     ///
     /// A `max_len` may be provided to indicate how many bytes the TLS implementation

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

@@ -716,6 +716,13 @@ where
         Ok(())
     }
 
+    fn on_tls_exporter_ready(
+        &mut self,
+        _: &impl super::TlsSession,
+    ) -> Result<(), crate::transport::Error> {
+        Ok(())
+    }
+
     fn receive_initial(&mut self, max_len: Option<usize>) -> Option<Bytes> {
         self.log("rx initial");
         self.initial.rx(max_len)

quic/s2n-quic-core/src/event.rs

@@ -127,3 +127,37 @@ impl IntoEvent<Timestamp> for crate::time::Timestamp {
         Timestamp(self)
     }
 }
+
+#[derive(Clone)]
+pub struct TlsSession<'a> {
+    session: &'a dyn crate::crypto::tls::TlsSession,
+}
+
+impl<'a> TlsSession<'a> {
+    #[doc(hidden)]
+    pub fn new(session: &'a dyn crate::crypto::tls::TlsSession) -> TlsSession<'a> {
+        TlsSession { session }
+    }
+
+    pub fn tls_exporter(
+        &self,
+        label: &[u8],
+        context: &[u8],
+        output: &mut [u8],
+    ) -> Result<(), crate::crypto::tls::TlsExportError> {
+        self.session.tls_exporter(label, context, output)
+    }
+}
+
+impl<'a> crate::event::IntoEvent<TlsSession<'a>> for TlsSession<'a> {
+    #[inline]
+    fn into_event(self) -> Self {
+        self
+    }
+}
+
+impl core::fmt::Debug for TlsSession<'_> {
+    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
+        f.debug_struct("TlsSession").finish_non_exhaustive()
+    }
+}

quic/s2n-quic-core/src/event/generated.rs

@@ -884,6 +884,14 @@ pub mod api {
     }
     #[derive(Clone, Debug)]
     #[non_exhaustive]
+    pub struct TlsExporterReady<'a> {
+        pub session: crate::event::TlsSession<'a>,
+    }
+    impl<'a> Event for TlsExporterReady<'a> {
+        const NAME: &'static str = "connectivity:tls_exporter_ready";
+    }
+    #[derive(Clone, Debug)]
+    #[non_exhaustive]
     #[doc = " Path challenge updated"]
     pub struct PathChallengeUpdated<'a> {
         pub path_challenge_status: PathChallengeStatus,
@@ -2012,6 +2020,17 @@ pub mod tracing {
             tracing :: event ! (target : "handshake_status_updated" , parent : id , tracing :: Level :: DEBUG , status = tracing :: field :: debug (status));
         }
         #[inline]
+        fn on_tls_exporter_ready(
+            &mut self,
+            context: &mut Self::ConnectionContext,
+            _meta: &api::ConnectionMeta,
+            event: &api::TlsExporterReady,
+        ) {
+            let id = context.id();
+            let api::TlsExporterReady { session } = event;
+            tracing :: event ! (target : "tls_exporter_ready" , parent : id , tracing :: Level :: DEBUG , session = tracing :: field :: debug (session));
+        }
+        #[inline]
         fn on_path_challenge_updated(
             &mut self,
             context: &mut Self::ConnectionContext,
@@ -3910,6 +3929,19 @@ pub mod builder {
         }
     }
     #[derive(Clone, Debug)]
+    pub struct TlsExporterReady<'a> {
+        pub session: crate::event::TlsSession<'a>,
+    }
+    impl<'a> IntoEvent<api::TlsExporterReady<'a>> for TlsExporterReady<'a> {
+        #[inline]
+        fn into_event(self) -> api::TlsExporterReady<'a> {
+            let TlsExporterReady { session } = self;
+            api::TlsExporterReady {
+                session: session.into_event(),
+            }
+        }
+    }
+    #[derive(Clone, Debug)]
     #[doc = " Path challenge updated"]
     pub struct PathChallengeUpdated<'a> {
         pub path_challenge_status: PathChallengeStatus,
@@ -4898,6 +4930,18 @@ mod traits {
             let _ = meta;
             let _ = event;
         }
+        #[doc = "Called when the `TlsExporterReady` event is triggered"]
+        #[inline]
+        fn on_tls_exporter_ready(
+            &mut self,
+            context: &mut Self::ConnectionContext,
+            meta: &ConnectionMeta,
+            event: &TlsExporterReady,
+        ) {
+            let _ = context;
+            let _ = meta;
+            let _ = event;
+        }
         #[doc = "Called when the `PathChallengeUpdated` event is triggered"]
         #[inline]
         fn on_path_challenge_updated(
@@ -5532,6 +5576,16 @@ mod traits {
             (self.1).on_handshake_status_updated(&mut context.1, meta, event);
         }
         #[inline]
+        fn on_tls_exporter_ready(
+            &mut self,
+            context: &mut Self::ConnectionContext,
+            meta: &ConnectionMeta,
+            event: &TlsExporterReady,
+        ) {
+            (self.0).on_tls_exporter_ready(&mut context.0, meta, event);
+            (self.1).on_tls_exporter_ready(&mut context.1, meta, event);
+        }
+        #[inline]
         fn on_path_challenge_updated(
             &mut self,
             context: &mut Self::ConnectionContext,
@@ -6000,6 +6054,8 @@ mod traits {
         fn on_connection_migration_denied(&mut self, event: builder::ConnectionMigrationDenied);
         #[doc = "Publishes a `HandshakeStatusUpdated` event to the publisher's subscriber"]
         fn on_handshake_status_updated(&mut self, event: builder::HandshakeStatusUpdated);
+        #[doc = "Publishes a `TlsExporterReady` event to the publisher's subscriber"]
+        fn on_tls_exporter_ready(&mut self, event: builder::TlsExporterReady);
         #[doc = "Publishes a `PathChallengeUpdated` event to the publisher's subscriber"]
         fn on_path_challenge_updated(&mut self, event: builder::PathChallengeUpdated);
         #[doc = "Publishes a `TlsClientHello` event to the publisher's subscriber"]
@@ -6327,6 +6383,15 @@ mod traits {
             self.subscriber.on_event(&self.meta, &event);
         }
         #[inline]
+        fn on_tls_exporter_ready(&mut self, event: builder::TlsExporterReady) {
+            let event = event.into_event();
+            self.subscriber
+                .on_tls_exporter_ready(self.context, &self.meta, &event);
+            self.subscriber
+                .on_connection_event(self.context, &self.meta, &event);
+            self.subscriber.on_event(&self.meta, &event);
+        }
+        #[inline]
         fn on_path_challenge_updated(&mut self, event: builder::PathChallengeUpdated) {
             let event = event.into_event();
             self.subscriber
@@ -6471,6 +6536,7 @@ pub mod testing {
         pub ecn_state_changed: u32,
         pub connection_migration_denied: u32,
         pub handshake_status_updated: u32,
+        pub tls_exporter_ready: u32,
         pub path_challenge_updated: u32,
         pub tls_client_hello: u32,
         pub tls_server_hello: u32,
@@ -6549,6 +6615,7 @@ pub mod testing {
                 ecn_state_changed: 0,
                 connection_migration_denied: 0,
                 handshake_status_updated: 0,
+                tls_exporter_ready: 0,
                 path_challenge_updated: 0,
                 tls_client_hello: 0,
                 tls_server_hello: 0,
@@ -6905,6 +6972,17 @@ pub mod testing {
                 self.output.push(format!("{meta:?} {event:?}"));
             }
         }
+        fn on_tls_exporter_ready(
+            &mut self,
+            _context: &mut Self::ConnectionContext,
+            meta: &api::ConnectionMeta,
+            event: &api::TlsExporterReady,
+        ) {
+            self.tls_exporter_ready += 1;
+            if self.location.is_some() {
+                self.output.push(format!("{meta:?} {event:?}"));
+            }
+        }
         fn on_path_challenge_updated(
             &mut self,
             _context: &mut Self::ConnectionContext,
@@ -7156,6 +7234,7 @@ pub mod testing {
         pub ecn_state_changed: u32,
         pub connection_migration_denied: u32,
         pub handshake_status_updated: u32,
+        pub tls_exporter_ready: u32,
         pub path_challenge_updated: u32,
         pub tls_client_hello: u32,
         pub tls_server_hello: u32,
@@ -7224,6 +7303,7 @@ pub mod testing {
                 ecn_state_changed: 0,
                 connection_migration_denied: 0,
                 handshake_status_updated: 0,
+                tls_exporter_ready: 0,
                 path_challenge_updated: 0,
                 tls_client_hello: 0,
                 tls_server_hello: 0,
@@ -7541,6 +7621,13 @@ pub mod testing {
                 self.output.push(format!("{event:?}"));
             }
         }
+        fn on_tls_exporter_ready(&mut self, event: builder::TlsExporterReady) {
+            self.tls_exporter_ready += 1;
+            let event = event.into_event();
+            if self.location.is_some() {
+                self.output.push(format!("{event:?}"));
+            }
+        }
         fn on_path_challenge_updated(&mut self, event: builder::PathChallengeUpdated) {
             self.path_challenge_updated += 1;
             let event = event.into_event();

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

@@ -250,6 +250,11 @@ struct HandshakeStatusUpdated {
     status: HandshakeStatus,
 }
 
+#[event("connectivity:tls_exporter_ready")]
+struct TlsExporterReady<'a> {
+    session: crate::event::TlsSession<'a>,
+}
+
 #[event("connectivity:path_challenge_updated")]
 /// Path challenge updated
 struct PathChallengeUpdated<'a> {

quic/s2n-quic-rustls/src/session.rs

@@ -26,6 +26,23 @@ pub struct Session {
     server_name: Option<ServerName>,
 }
 
+impl tls::TlsSession for Session {
+    fn tls_exporter(
+        &self,
+        label: &[u8],
+        context: &[u8],
+        output: &mut [u8],
+    ) -> Result<(), tls::TlsExportError> {
+        match self
+            .connection
+            .export_keying_material(output, label, Some(context))
+        {
+            Ok(_) => Ok(()),
+            Err(_) => Err(tls::TlsExportError::failure()),
+        }
+    }
+}
+
 impl fmt::Debug for Session {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         f.debug_struct("Session")
@@ -149,6 +166,7 @@ impl Session {
             if !self.emitted_handshake_complete {
                 self.rx_phase.transition();
                 context.on_handshake_complete()?;
+                context.on_tls_exporter_ready(self)?;
             }
 
             self.emitted_handshake_complete = true;

quic/s2n-quic-tls/Cargo.toml

@@ -21,7 +21,7 @@ libc = "0.2"
 s2n-codec = { version = "=0.7.0", path = "../../common/s2n-codec", default-features = false }
 s2n-quic-core = { version = "=0.28.0", path = "../s2n-quic-core", default-features = false, features = ["alloc"] }
 s2n-quic-crypto = { version = "=0.29.0", path = "../s2n-quic-crypto", default-features = false }
-s2n-tls = { version = "=0.0.36", features = ["quic"] }
+s2n-tls = { version = "=0.0.39", features = ["quic"] }
 
 [dev-dependencies]
 checkers = "0.6"

quic/s2n-quic-tls/src/session.rs

@@ -77,6 +77,19 @@ impl CryptoSuite for Session {
     type RetryKey = <Suite as CryptoSuite>::RetryKey;
 }
 
+impl tls::TlsSession for Session {
+    fn tls_exporter(
+        &self,
+        label: &[u8],
+        context: &[u8],
+        output: &mut [u8],
+    ) -> Result<(), tls::TlsExportError> {
+        self.connection
+            .tls_exporter(label, context, output)
+            .map_err(|_| tls::TlsExportError::failure())
+    }
+}
+
 impl tls::Session for Session {
     fn poll<W>(&mut self, context: &mut W) -> Poll<Result<(), transport::Error>>
     where
@@ -109,6 +122,7 @@ impl tls::Session for Session {
                 if !self.handshake_complete {
                     self.state.on_handshake_complete();
                     context.on_handshake_complete()?;
+                    context.on_tls_exporter_ready(self)?;
                     self.handshake_complete = true;
                 }
                 Poll::Ready(Ok(()))

quic/s2n-quic-transport/src/space/session_context.rs

@@ -457,6 +457,17 @@ impl<'a, Config: endpoint::Config, Pub: event::ConnectionPublisher>
         Ok(())
     }
 
+    fn on_tls_exporter_ready(
+        &mut self,
+        session: &impl tls::TlsSession,
+    ) -> Result<(), transport::Error> {
+        self.publisher
+            .on_tls_exporter_ready(event::builder::TlsExporterReady {
+                session: s2n_quic_core::event::TlsSession::new(session),
+            });
+        Ok(())
+    }
+
     fn on_handshake_complete(&mut self) -> Result<(), transport::Error> {
         // After the handshake is complete, the handshake crypto stream should be completely
         // finished

quic/s2n-quic/src/tests.rs

@@ -45,6 +45,7 @@ mod client_handshake_confirm;
 #[cfg(not(target_os = "windows"))]
 mod mtls;
 
+mod exporter;
 mod issue_1361;
 mod issue_1427;
 mod issue_1464;