ethereum.prague.requests

Requests were introduced in EIP-7685 as a general purpose framework for storing contract-triggered requests. It extends the execution header and body with a single field each to store the request information. This inherently exposes the requests to the consensus layer, which can then process each one.

DEPOSIT_CONTRACT_ADDRESS

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DEPOSIT_CONTRACT_ADDRESS = hex_to_address(
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    "0x00000000219ab540356cbb839cbe05303d7705fa"
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)

DEPOSIT_EVENT_SIGNATURE_HASH

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DEPOSIT_EVENT_SIGNATURE_HASH = hex_to_bytes32(
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    "0x649bbc62d0e31342afea4e5cd82d4049e7e1ee912fc0889aa790803be39038c5"
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)

DEPOSIT_REQUEST_TYPE

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DEPOSIT_REQUEST_TYPE = b"\x00"

WITHDRAWAL_REQUEST_TYPE

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WITHDRAWAL_REQUEST_TYPE = b"\x01"

CONSOLIDATION_REQUEST_TYPE

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CONSOLIDATION_REQUEST_TYPE = b"\x02"

DEPOSIT_EVENT_LENGTH

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DEPOSIT_EVENT_LENGTH = Uint(576)

PUBKEY_OFFSET

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PUBKEY_OFFSET = Uint(160)

WITHDRAWAL_CREDENTIALS_OFFSET

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WITHDRAWAL_CREDENTIALS_OFFSET = Uint(256)

AMOUNT_OFFSET

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AMOUNT_OFFSET = Uint(320)

SIGNATURE_OFFSET

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SIGNATURE_OFFSET = Uint(384)

INDEX_OFFSET

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INDEX_OFFSET = Uint(512)

PUBKEY_SIZE

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PUBKEY_SIZE = Uint(48)

WITHDRAWAL_CREDENTIALS_SIZE

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WITHDRAWAL_CREDENTIALS_SIZE = Uint(32)

AMOUNT_SIZE

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AMOUNT_SIZE = Uint(8)

SIGNATURE_SIZE

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SIGNATURE_SIZE = Uint(96)

INDEX_SIZE

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INDEX_SIZE = Uint(8)

extract_deposit_data

Extracts Deposit Request from the DepositContract.DepositEvent data.

Raises

InvalidBlock : If the deposit contract did not produce a valid log.

def extract_deposit_data(​data: Bytes​) -> Bytes:
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    """
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    Extracts Deposit Request from the DepositContract.DepositEvent data.
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    Raises
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    ------
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    InvalidBlock :
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        If the deposit contract did not produce a valid log.
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    """
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    if ulen(data) != DEPOSIT_EVENT_LENGTH:
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        raise InvalidBlock("Invalid deposit event data length")
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    # Check that all the offsets are in order
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    pubkey_offset = Uint.from_be_bytes(data[0:32])
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    if pubkey_offset != PUBKEY_OFFSET:
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        raise InvalidBlock("Invalid pubkey offset in deposit log")
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    withdrawal_credentials_offset = Uint.from_be_bytes(data[32:64])
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    if withdrawal_credentials_offset != WITHDRAWAL_CREDENTIALS_OFFSET:
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        raise InvalidBlock(
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            "Invalid withdrawal credentials offset in deposit log"
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        )
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    amount_offset = Uint.from_be_bytes(data[64:96])
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    if amount_offset != AMOUNT_OFFSET:
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        raise InvalidBlock("Invalid amount offset in deposit log")
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    signature_offset = Uint.from_be_bytes(data[96:128])
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    if signature_offset != SIGNATURE_OFFSET:
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        raise InvalidBlock("Invalid signature offset in deposit log")
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    index_offset = Uint.from_be_bytes(data[128:160])
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    if index_offset != INDEX_OFFSET:
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        raise InvalidBlock("Invalid index offset in deposit log")
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    # Check that all the sizes are in order
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    pubkey_size = Uint.from_be_bytes(
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        data[pubkey_offset : pubkey_offset + Uint(32)]
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    )
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    if pubkey_size != PUBKEY_SIZE:
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        raise InvalidBlock("Invalid pubkey size in deposit log")
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    pubkey = data[
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        pubkey_offset + Uint(32) : pubkey_offset + Uint(32) + PUBKEY_SIZE
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    ]
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    withdrawal_credentials_size = Uint.from_be_bytes(
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        data[
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            withdrawal_credentials_offset : withdrawal_credentials_offset
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            + Uint(32)
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        ],
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    )
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    if withdrawal_credentials_size != WITHDRAWAL_CREDENTIALS_SIZE:
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        raise InvalidBlock(
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            "Invalid withdrawal credentials size in deposit log"
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        )
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    withdrawal_credentials = data[
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        withdrawal_credentials_offset
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        + Uint(32) : withdrawal_credentials_offset
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        + Uint(32)
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        + WITHDRAWAL_CREDENTIALS_SIZE
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    ]
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    amount_size = Uint.from_be_bytes(
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        data[amount_offset : amount_offset + Uint(32)]
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    )
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    if amount_size != AMOUNT_SIZE:
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        raise InvalidBlock("Invalid amount size in deposit log")
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    amount = data[
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        amount_offset + Uint(32) : amount_offset + Uint(32) + AMOUNT_SIZE
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    ]
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    signature_size = Uint.from_be_bytes(
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        data[signature_offset : signature_offset + Uint(32)]
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    )
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    if signature_size != SIGNATURE_SIZE:
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        raise InvalidBlock("Invalid signature size in deposit log")
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    signature = data[
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        signature_offset
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        + Uint(32) : signature_offset
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        + Uint(32)
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        + SIGNATURE_SIZE
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    ]
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    index_size = Uint.from_be_bytes(
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        data[index_offset : index_offset + Uint(32)]
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    )
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    if index_size != INDEX_SIZE:
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        raise InvalidBlock("Invalid index size in deposit log")
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    index = data[
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        index_offset + Uint(32) : index_offset + Uint(32) + INDEX_SIZE
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    ]
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    return pubkey + withdrawal_credentials + amount + signature + index

parse_deposit_requests

Parse deposit requests from the block output.

def parse_deposit_requests(​block_output: BlockOutput​) -> Bytes:
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    """
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    Parse deposit requests from the block output.
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    """
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    deposit_requests: Bytes = b""
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    for key in block_output.receipt_keys:
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        receipt = trie_get(block_output.receipts_trie, key)
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        assert receipt is not None
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        decoded_receipt = decode_receipt(receipt)
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        for log in decoded_receipt.logs:
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            if log.address == DEPOSIT_CONTRACT_ADDRESS:
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                if (
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                    len(log.topics) > 0
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                    and log.topics[0] == DEPOSIT_EVENT_SIGNATURE_HASH
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                ):
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                    request = extract_deposit_data(log.data)
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                    deposit_requests += request
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    return deposit_requests

compute_requests_hash

Get the hash of the requests using the SHA2-256 algorithm.

Parameters

requests : Bytes The requests to hash.

Returns

requests_hash : Bytes The hash of the requests.

def compute_requests_hash(​requests: List[Bytes]​) -> Bytes:
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    """
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    Get the hash of the requests using the SHA2-256 algorithm.
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    Parameters
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    ----------
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    requests : Bytes
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        The requests to hash.
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    Returns
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    -------
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    requests_hash : Bytes
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        The hash of the requests.
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    """
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    m = sha256()
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    for request in requests:
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        m.update(sha256(request).digest())
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    return m.digest()