fix: enforce unsupported fork rules on get_payload_v3 (#4562)

crates/payload/basic/src/lib.rs

@@ -412,6 +412,10 @@ where
         build_empty_payload(&self.client, self.config.clone()).map(Arc::new)
     }
 
+    fn payload_attributes(&self) -> Result<PayloadBuilderAttributes, PayloadBuilderError> {
+        Ok(self.config.attributes.clone())
+    }
+
     fn resolve(&mut self) -> (Self::ResolvePayloadFuture, KeepPayloadJobAlive) {
         let best_payload = self.best_payload.take();
         let maybe_better = self.pending_block.take();

crates/payload/builder/src/lib.rs

@@ -86,6 +86,10 @@
 //!     Ok(Arc::new(payload))
 //! }
 //!
+//! fn payload_attributes(&self) -> Result<PayloadBuilderAttributes, PayloadBuilderError> {
+//!     Ok(self.attributes.clone())
+//! }
+//!
 //! fn resolve(&mut self) -> (Self::ResolvePayloadFuture, KeepPayloadJobAlive) {
 //!        let payload = self.best_payload();
 //!        (futures_util::future::ready(payload), KeepPayloadJobAlive::No)

crates/payload/builder/src/service.rs

@@ -48,6 +48,16 @@ impl PayloadStore {
     ) -> Option<Result<Arc<BuiltPayload>, PayloadBuilderError>> {
         self.inner.best_payload(id).await
     }
+
+    /// Returns the payload attributes associated with the given identifier.
+    ///
+    /// Note: this returns the attributes of the payload and does not resolve the job.
+    pub async fn payload_attributes(
+        &self,
+        id: PayloadId,
+    ) -> Option<Result<PayloadBuilderAttributes, PayloadBuilderError>> {
+        self.inner.payload_attributes(id).await
+    }
 }
 
 impl From<PayloadBuilderHandle> for PayloadStore {
@@ -94,6 +104,18 @@ impl PayloadBuilderHandle {
         rx.await.ok()?
     }
 
+    /// Returns the payload attributes associated with the given identifier.
+    ///
+    /// Note: this returns the attributes of the payload and does not resolve the job.
+    pub async fn payload_attributes(
+        &self,
+        id: PayloadId,
+    ) -> Option<Result<PayloadBuilderAttributes, PayloadBuilderError>> {
+        let (tx, rx) = oneshot::channel();
+        self.to_service.send(PayloadServiceCommand::PayloadAttributes(id, tx)).ok()?;
+        rx.await.ok()?
+    }
+
     /// Sends a message to the service to start building a new payload for the given payload.
     ///
     /// This is the same as [PayloadBuilderHandle::new_payload] but does not wait for the result and
@@ -178,6 +200,17 @@ where
         self.payload_jobs.iter().find(|(_, job_id)| *job_id == id).map(|(j, _)| j.best_payload())
     }
 
+    /// Returns the payload attributes for the given payload.
+    fn payload_attributes(
+        &self,
+        id: PayloadId,
+    ) -> Option<Result<PayloadBuilderAttributes, PayloadBuilderError>> {
+        self.payload_jobs
+            .iter()
+            .find(|(_, job_id)| *job_id == id)
+            .map(|(j, _)| j.payload_attributes())
+    }
+
     /// Returns the best payload for the given identifier that has been built so far and terminates
     /// the job if requested.
     fn resolve(&mut self, id: PayloadId) -> Option<PayloadFuture> {
@@ -262,6 +295,9 @@ where
                     PayloadServiceCommand::BestPayload(id, tx) => {
                         let _ = tx.send(this.best_payload(id));
                     }
+                    PayloadServiceCommand::PayloadAttributes(id, tx) => {
+                        let _ = tx.send(this.payload_attributes(id));
+                    }
                     PayloadServiceCommand::Resolve(id, tx) => {
                         let _ = tx.send(this.resolve(id));
                     }
@@ -287,6 +323,11 @@ enum PayloadServiceCommand {
     ),
     /// Get the best payload so far
     BestPayload(PayloadId, oneshot::Sender<Option<Result<Arc<BuiltPayload>, PayloadBuilderError>>>),
+    /// Get the payload attributes for the given payload
+    PayloadAttributes(
+        PayloadId,
+        oneshot::Sender<Option<Result<PayloadBuilderAttributes, PayloadBuilderError>>>,
+    ),
     /// Resolve the payload and return the payload
     Resolve(PayloadId, oneshot::Sender<Option<PayloadFuture>>),
 }

crates/payload/builder/src/test_utils.rs

@@ -68,6 +68,10 @@ impl PayloadJob for TestPayloadJob {
         )))
     }
 
+    fn payload_attributes(&self) -> Result<PayloadBuilderAttributes, PayloadBuilderError> {
+        Ok(self.attr.clone())
+    }
+
     fn resolve(&mut self) -> (Self::ResolvePayloadFuture, KeepPayloadJobAlive) {
         let fut = futures_util::future::ready(self.best_payload());
         (fut, KeepPayloadJobAlive::No)

crates/payload/builder/src/traits.rs

@@ -26,6 +26,9 @@ pub trait PayloadJob: Future<Output = Result<(), PayloadBuilderError>> + Send +
     /// Note: This is never called by the CL.
     fn best_payload(&self) -> Result<Arc<BuiltPayload>, PayloadBuilderError>;
 
+    /// Returns the payload attributes for the payload being built.
+    fn payload_attributes(&self) -> Result<PayloadBuilderAttributes, PayloadBuilderError>;
+
     /// Called when the payload is requested by the CL.
     ///
     /// This is invoked on [`engine_getPayloadV2`](https://github.com/ethereum/execution-apis/blob/main/src/engine/shanghai.md#engine_getpayloadv2) and [`engine_getPayloadV1`](https://github.com/ethereum/execution-apis/blob/main/src/engine/paris.md#engine_getpayloadv1).

crates/rpc/rpc-engine-api/src/engine_api.rs

@@ -208,6 +208,24 @@ where
         &self,
         payload_id: PayloadId,
     ) -> EngineApiResult<ExecutionPayloadEnvelopeV3> {
+        // First we fetch the payload attributes to check the timestamp
+        let attributes = self
+            .inner
+            .payload_store
+            .payload_attributes(payload_id)
+            .await
+            .ok_or(EngineApiError::UnknownPayload)??;
+
+        // From the Engine API spec:
+        // <https://github.com/ethereum/execution-apis/blob/ff43500e653abde45aec0f545564abfb648317af/src/engine/cancun.md#specification-2>
+        //
+        // 1. Client software **MUST** return `-38005: Unsupported fork` error if the `timestamp` of
+        //    the built payload does not fall within the time frame of the Cancun fork.
+        if !self.inner.chain_spec.is_cancun_activated_at_timestamp(attributes.timestamp) {
+            return Err(EngineApiError::UnsupportedFork)
+        }
+
+        // Now resolve the payload
         Ok(self
             .inner
             .payload_store