fix: use execution timestamp instead of slot timestamp (#401)

Author: srdtrk

e2e/interchaintestv8/e2esuite/light_clients.go

@@ -104,8 +104,6 @@ func (s *TestSuite) createEthereumLightClient(
 	proofOfIBCContract, err := eth.EthAPI.GetProof(ibcContractAddress, []string{ics26router.IbcStoreStorageSlot}, executionNumberHex)
 	s.Require().NoError(err)
 
-	unixTimestamp := bootstrap.Data.Header.Execution.Timestamp
-
 	currentPeriod := latestSlot / spec.Period()
 	clientUpdates, err := eth.BeaconAPIClient.GetLightClientUpdates(currentPeriod, 1)
 	s.Require().NoError(err)
@@ -117,7 +115,7 @@ func (s *TestSuite) createEthereumLightClient(
 		Slot:                 bootstrap.Data.Header.Beacon.Slot,
 		StateRoot:            bootstrap.Data.Header.Execution.StateRoot,
 		StorageRoot:          proofOfIBCContract.StorageHash,
-		Timestamp:            unixTimestamp,
+		Timestamp:            bootstrap.Data.Header.Execution.Timestamp,
 		CurrentSyncCommittee: bootstrap.Data.CurrentSyncCommittee.AggregatePubkey,
 		NextSyncCommittee:    clientUpdates[0].Data.NextSyncCommittee.AggregatePubkey,
 	}

e2e/interchaintestv8/wasm/cw_ics08_wasm_eth.wasm.gz

@@ -8,24 +8,23 @@ use ethereum_types::consensus::sync_committee::SyncCommittee;
 
 use crate::{error::EthereumIBCError, header::ActiveSyncCommittee, verify::BlsVerify};
 
-/// The consensus state of the Ethereum light client
+/// The consensus state of the Ethereum light client corresponding to a finalized header
 #[derive(Serialize, Deserialize, JsonSchema, PartialEq, Eq, Debug, Clone)]
 pub struct ConsensusState {
-    /// The slot number
+    /// The slot number of the finalized header
     pub slot: u64,
-    /// The state merkle root
+    /// The state merkle root of the finalized header
     #[schemars(with = "String")]
     pub state_root: B256,
-    /// The storage merkle root
+    /// The storage merkle root of the tracked contract at the finalized header
     #[schemars(with = "String")]
     pub storage_root: B256,
-    /// The unix timestamp at the time of the slot.
-    /// It is calculated from the genesis time and slots per.
+    /// The execution timestamp of the finalized header
     pub timestamp: u64,
-    /// aggregate public key of current sync committee
+    /// aggregate public key of current sync committee at the finalized header
     #[schemars(with = "String")]
     pub current_sync_committee: FixedBytes<48>,
-    /// aggregate public key of next sync committee
+    /// aggregate public key of next sync committee at the finalized header if known
     #[schemars(with = "String")]
     pub next_sync_committee: Option<FixedBytes<48>>,
 }

packages/ethereum/ethereum-light-client/src/consensus_state.rs

@@ -55,12 +55,9 @@ pub fn update_consensus_state(
 
     if consensus_update.finalized_header.beacon.slot > current_consensus_state.slot {
         new_consensus_state.slot = consensus_update.finalized_header.beacon.slot;
-
         new_consensus_state.state_root = consensus_update.finalized_header.execution.state_root;
         new_consensus_state.storage_root = header.account_update.account_proof.storage_root;
-
-        new_consensus_state.timestamp = current_client_state
-            .compute_timestamp_at_slot(consensus_update.finalized_header.beacon.slot);
+        new_consensus_state.timestamp = consensus_update.finalized_header.execution.timestamp;
 
         if current_client_state.latest_slot < consensus_update.finalized_header.beacon.slot {
             new_client_state = Some(ClientState {

packages/ethereum/ethereum-light-client/src/update.rs

@@ -116,8 +116,6 @@ func main() {
 	}
 	fmt.Printf("Proof of IBC contract: %+v\n", proofOfIBCContract)
 
-	unixTimestamp := bootstrap.Data.Header.Execution.Timestamp
-
 	currentPeriod := latestSlot / spec.Period()
 	clientUpdates, err := beaconAPI.GetLightClientUpdates(currentPeriod, 1)
 	if err != nil {
@@ -131,7 +129,7 @@ func main() {
 		Slot:                 bootstrap.Data.Header.Beacon.Slot,
 		StateRoot:            bootstrap.Data.Header.Execution.StateRoot,
 		StorageRoot:          proofOfIBCContract.StorageHash,
-		Timestamp:            unixTimestamp,
+		Timestamp:            bootstrap.Data.Header.Execution.Timestamp,
 		CurrentSyncCommittee: bootstrap.Data.CurrentSyncCommittee.AggregatePubkey,
 		NextSyncCommittee:    clientUpdates[0].Data.NextSyncCommittee.AggregatePubkey,
 	}