ER::domain_block_hash

[vedhavyas]

Detect if the external ER has a different domain_block_hash field, if so the operator will need to construct a fraud proof that includes all components necessary to construct the domain block header and data that prove the integrity of these components:

• ER, the targeted invalid ER, and storage proof that proves this ER is indeed included in the consensus chain state
• parent_er, and storage proof that proves this parent_er is indeed included in the consensus chain state
• digest, and storage proof of the pallet_system::Digest storage item of the domain chain

Verification steps:

• Verify the ER storage proof with the consensus chain state root
• Verify the parent_er storage proof with the consensus chain state root
• Verify ER::parent_domain_block_receipt_hash == parent_er.hash()
• Verify the digest storage with ER::final_state_root
• Construct the expected_domain_header with:

Header::new(ER::domain_block_number, ER::domain_block_extrinsic_root, ER::final_state_root, parent_er.domain_block_hash, digest)

• Verify that expected_domain_header.hash() != ER::domain_block_hash

Estimation: 2 days