CLPR-5.3: EthereumBLS Verifier (Ethereum-to-Hiero)

Story CLPR-5.3: EthereumBLS Verifier (Ethereum-to-Hiero)

Parent Epic: CLPR-5: Hiero Verifier Contracts
Repo: hiero-ledger/hiero-consensus-node

Objective

Implement the EthereumBLS verifier contract on Hiero that validates Ethereum sync committee BLS signatures and Merkle-Patricia trie proofs.

Acceptance Criteria

• AC-1: Verifies BLS aggregate signatures from the Ethereum sync committee.
• AC-2: Tracks sync committee rotation (~27 hours on Ethereum mainnet).
• AC-3: Verifies Merkle-Patricia trie proofs from Ethereum state root to contract storage slots.
• AC-4: Extracts verified ClprQueueMetadata and ClprMessagePayload[].
• AC-5: Decodes Ethereum CLPR Service storage layout to reconstruct cross-platform types.
• AC-6: Should verify proof is from a finalized block (not reorgable).
• AC-7: Reverts on: invalid BLS signature, invalid Merkle-Patricia proof, unrecognized storage layout.

Dependencies

• CLPR-5.1 (IClprVerifier interface)
• CLPR-6 (Ethereum ClprService — defines the storage layout)
• BLS12-381 precompile availability on Hiero EVM

Risk

High — BLS12-381 expensive in EVM. May need Hiero precompile support. Sync committee tracking adds state management.

Review the IClprVerifier interface from CLPR-5.1 and the Ethereum ClprService storage layout from CLPR-6 first, then confirm BLS12-381 precompile availability on Hiero EVM. Done means the verifier handles valid signatures, committee rotation, finalized-block proofs, storage decoding, and the listed invalid-input reverts.