Steel Commitments

// Create an EVM environment from that provider
let mut env = EthEvmEnv::builder()
    .chain_spec(&ETH_SEPOLIA_CHAIN_SPEC)
    .provider(provider.clone())
    .block_number(20842508)
    .build()
    .await?;

let evm_input = env.into_input().await?;

// Read the input from the guest environment.
let input: EthEvmInput = env::read();
let contract: Address = env::read();
let account: Address = env::read();

// Converts the input into a `EvmEnv`
let env = input.into_env(&ETH_SEPOLIA_CHAIN_SPEC);

    // Commit the block hash and number used when deriving `view_call_env` to the journal.
let journal = Journal {
    commitment: evm_env.into_commitment(),
    tokenAddress: contract,
};
env::commit_slice(&journal.abi_encode());

struct Commitment {
    uint256 id;
    bytes32 digest;
    bytes32 configID
}

require(Steel.validateCommitment(journal.commitment), "Invalid commitment");

function validateCommitment(Commitment memory commitment) internal view returns (bool) {
    (uint240 claimID, uint16 version) = Encoding.decodeVersionedID(commitment.id);
    if (version == 0) {
        return validateBlockCommitment(claimID, commitment.digest);
    } else if (version == 1) {
        return validateBeaconCommitment(claimID, commitment.digest);
    } else {
        revert InvalidCommitmentVersion();
    }
}

/// @notice Validates if the provided block commitment matches the block hash of the given block number.
/// @param blockNumber The block number to compare against.
/// @param blockHash The block hash to validate.
/// @return True if the block's block hash matches the block hash, false otherwise.
function validateBlockCommitment(uint256 blockNumber, bytes32 blockHash) internal view returns (bool) {
    if (block.number - blockNumber > 256) {
        revert CommitmentTooOld();
    }
    return blockHash == blockhash(blockNumber);
}

/// @notice Validates if the provided beacon commitment matches the block root of the given timestamp.
/// @param timestamp The timestamp to compare against.
/// @param blockRoot The block root to validate.
/// @return True if the block's block root matches the block root, false otherwise.
function validateBeaconCommitment(uint256 timestamp, bytes32 blockRoot) internal view returns (bool) {
    if (block.timestamp - timestamp > 12 * 8191) {
        revert CommitmentTooOld();
    }
    return blockRoot == Beacon.parentBlockRoot(timestamp);
}