Add DataColumnSidecar gossip topic and message handling (#6147)

* Add `DataColumnSidecar` gossip topic and verification (#5050 and #5783).

* Remove gossip verification changes (#5783).

* Merge branch 'unstable' into data-column-gossip

# Conflicts:
#	beacon_node/beacon_chain/src/data_column_verification.rs
#	beacon_node/beacon_chain/src/lib.rs

* Add gossip cache timeout for data columns. Rename data column metrics for consistency.

* Remove usage of `unimplemented!` and address review comments.

* Remove unnused `GossipDataColumnError` variants and address review comments.

* Merge branch 'unstable' into data-column-gossip

* Update Cargo.lock

* Arc `ChainSpec` in discovery to avoid performance regression when needing to clone it repeatedly.

beacon_node/beacon_chain/src/block_verification.rs

@@ -54,6 +54,7 @@ use crate::block_verification_types::{
     AsBlock, BlockContentsError, BlockImportData, GossipVerifiedBlockContents, RpcBlock,
 };
 use crate::data_availability_checker::{AvailabilityCheckError, MaybeAvailableBlock};
+use crate::data_column_verification::GossipDataColumnError;
 use crate::eth1_finalization_cache::Eth1FinalizationData;
 use crate::execution_payload::{
     is_optimistic_candidate_block, validate_execution_payload_for_gossip, validate_merge_block,
@@ -303,6 +304,13 @@ pub enum BlockError<E: EthSpec> {
     /// TODO: We may need to penalize the peer that gave us a potentially invalid rpc blob.
     /// https://github.com/sigp/lighthouse/issues/4546
     AvailabilityCheck(AvailabilityCheckError),
+    /// An internal error has occurred when processing the block or sidecars.
+    ///
+    /// ## Peer scoring
+    ///
+    /// We were unable to process this block due to an internal error. It's unclear if the block is
+    /// valid.
+    InternalError(String),
 }
 
 impl<E: EthSpec> From<AvailabilityCheckError> for BlockError<E> {
@@ -523,6 +531,20 @@ impl<E: EthSpec> BlockSlashInfo<GossipBlobError<E>> {
     }
 }
 
+impl BlockSlashInfo<GossipDataColumnError> {
+    pub fn from_early_error_data_column(
+        header: SignedBeaconBlockHeader,
+        e: GossipDataColumnError,
+    ) -> Self {
+        match e {
+            GossipDataColumnError::ProposalSignatureInvalid => BlockSlashInfo::SignatureInvalid(e),
+            // `InvalidSignature` could indicate any signature in the block, so we want
+            // to recheck the proposer signature alone.
+            _ => BlockSlashInfo::SignatureNotChecked(header, e),
+        }
+    }
+}
+
 /// Process invalid blocks to see if they are suitable for the slasher.
 ///
 /// If no slasher is configured, this is a no-op.
@@ -2007,6 +2029,23 @@ impl<E: EthSpec> BlockBlobError for GossipBlobError<E> {
     }
 }
 
+impl BlockBlobError for GossipDataColumnError {
+    fn not_later_than_parent_error(data_column_slot: Slot, parent_slot: Slot) -> Self {
+        GossipDataColumnError::IsNotLaterThanParent {
+            data_column_slot,
+            parent_slot,
+        }
+    }
+
+    fn unknown_validator_error(validator_index: u64) -> Self {
+        GossipDataColumnError::UnknownValidator(validator_index)
+    }
+
+    fn proposer_signature_invalid() -> Self {
+        GossipDataColumnError::ProposalSignatureInvalid
+    }
+}
+
 /// Performs a cheap (time-efficient) state advancement so the committees and proposer shuffling for
 /// `slot` can be obtained from `state`.
 ///