ethereum.gray_glacier.forkethereum.paris.fork

Ethereum Specification ^^^^^^^^^^^^^^^^^^^^^^

.. contents:: Table of Contents :backlinks: none :local:

Introduction

Entry point for the Ethereum specification.

BLOCK_REWARD

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BLOCK_REWARD = U256(2 * 10**18)

BASE_FEE_MAX_CHANGE_DENOMINATOR

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BASE_FEE_MAX_CHANGE_DENOMINATOR = Uint(8)

ELASTICITY_MULTIPLIER

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ELASTICITY_MULTIPLIER = Uint(2)

GAS_LIMIT_ADJUSTMENT_FACTOR

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GAS_LIMIT_ADJUSTMENT_FACTOR = Uint(1024)

GAS_LIMIT_MINIMUM

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GAS_LIMIT_MINIMUM = Uint(5000)

MINIMUM_DIFFICULTY

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MINIMUM_DIFFICULTY = Uint(131072)

MAX_OMMER_DEPTH

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MAX_OMMER_DEPTH = Uint(6)

BOMB_DELAY_BLOCKS

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BOMB_DELAY_BLOCKS = 11400000

EMPTY_OMMER_HASH

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EMPTY_OMMER_HASH = keccak256(rlp.encode([]))

BlockChain

History and current state of the block chain.

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@dataclass
class BlockChain:

blocks

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    blocks: List[Block]

state

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    state: State

chain_id

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    chain_id: U64

apply_fork

Transforms the state from the previous hard fork (old) into the block chain object for this hard fork and returns it.

When forks need to implement an irregular state transition, this function is used to handle the irregularity. See the :ref:DAO Fork <dao-fork> for an example.

Parameters

old : Previous block chain object.

Returns

new : BlockChain Upgraded block chain object for this hard fork.

def apply_fork(old: BlockChain) -> BlockChain:
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    """
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    Transforms the state from the previous hard fork (`old`) into the block
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    chain object for this hard fork and returns it.
85
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    When forks need to implement an irregular state transition, this function
87
    is used to handle the irregularity. See the :ref:`DAO Fork <dao-fork>` for
88
    an example.
89
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    Parameters
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    ----------
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    old :
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        Previous block chain object.
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    Returns
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    -------
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    new : `BlockChain`
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        Upgraded block chain object for this hard fork.
99
    """
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    return old

get_last_256_block_hashes

Obtain the list of hashes of the previous 256 blocks in order of increasing block number.

This function will return less hashes for the first 256 blocks.

The BLOCKHASH opcode needs to access the latest hashes on the chain, therefore this function retrieves them.

Parameters

chain : History and current state.

Returns

recent_block_hashes : List[Hash32] Hashes of the recent 256 blocks in order of increasing block number.

def get_last_256_block_hashes(chain: BlockChain) -> List[Hash32]:
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    """
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    Obtain the list of hashes of the previous 256 blocks in order of
106
    increasing block number.
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    This function will return less hashes for the first 256 blocks.
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    The ``BLOCKHASH`` opcode needs to access the latest hashes on the chain,
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    therefore this function retrieves them.
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    Parameters
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    ----------
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    chain :
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        History and current state.
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    Returns
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    -------
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    recent_block_hashes : `List[Hash32]`
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        Hashes of the recent 256 blocks in order of increasing block number.
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    """
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    recent_blocks = chain.blocks[-255:]
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    # TODO: This function has not been tested rigorously
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    if len(recent_blocks) == 0:
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        return []
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    recent_block_hashes = []
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    for block in recent_blocks:
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        prev_block_hash = block.header.parent_hash
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        recent_block_hashes.append(prev_block_hash)
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    # We are computing the hash only for the most recent block and not for
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    # the rest of the blocks as they have successors which have the hash of
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    # the current block as parent hash.
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    most_recent_block_hash = keccak256(rlp.encode(recent_blocks[-1].header))
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    recent_block_hashes.append(most_recent_block_hash)
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    return recent_block_hashes

state_transition

Attempts to apply a block to an existing block chain.

All parts of the block's contents need to be verified before being added to the chain. Blocks are verified by ensuring that the contents of the block make logical sense with the contents of the parent block. The information in the block's header must also match the corresponding information in the block.

To implement Ethereum, in theory clients are only required to store the most recent 255 blocks of the chain since as far as execution is concerned, only those blocks are accessed. Practically, however, clients should store more blocks to handle reorgs.

Parameters

chain : History and current state. block : Block to apply to chain.

def state_transition(chain: BlockChain, ​​block: Block) -> None:
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    """
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    Attempts to apply a block to an existing block chain.
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    All parts of the block's contents need to be verified before being added
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    to the chain. Blocks are verified by ensuring that the contents of the
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    block make logical sense with the contents of the parent block. The
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    information in the block's header must also match the corresponding
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    information in the block.
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    To implement Ethereum, in theory clients are only required to store the
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    most recent 255 blocks of the chain since as far as execution is
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    concerned, only those blocks are accessed. Practically, however, clients
156
    should store more blocks to handle reorgs.
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    Parameters
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    ----------
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    chain :
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        History and current state.
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    block :
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        Block to apply to `chain`.
164
    """
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    validate_header(chain, block.header)
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    validate_ommers(block.ommers, block.header, chain)
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    if block.ommers != ():
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        raise InvalidBlock
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    block_env = vm.BlockEnvironment(
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        chain_id=chain.chain_id,
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        state=chain.state,
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        block_gas_limit=block.header.gas_limit,
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        block_hashes=get_last_256_block_hashes(chain),
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        coinbase=block.header.coinbase,
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        number=block.header.number,
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        base_fee_per_gas=block.header.base_fee_per_gas,
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        time=block.header.timestamp,
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        difficulty=block.header.difficulty,
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        prev_randao=block.header.prev_randao,
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    )
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    block_output = apply_body(
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        block_env=block_env,
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        transactions=block.transactions,
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        ommers=block.ommers,
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    )
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    block_state_root = state_root(block_env.state)
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    transactions_root = root(block_output.transactions_trie)
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    receipt_root = root(block_output.receipts_trie)
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    block_logs_bloom = logs_bloom(block_output.block_logs)
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    if block_output.block_gas_used != block.header.gas_used:
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        raise InvalidBlock(
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            f"{block_output.block_gas_used} != {block.header.gas_used}"
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        )
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    if transactions_root != block.header.transactions_root:
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        raise InvalidBlock
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    if block_state_root != block.header.state_root:
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        raise InvalidBlock
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    if receipt_root != block.header.receipt_root:
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        raise InvalidBlock
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    if block_logs_bloom != block.header.bloom:
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        raise InvalidBlock
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    chain.blocks.append(block)
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    if len(chain.blocks) > 255:
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        # Real clients have to store more blocks to deal with reorgs, but the
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        # protocol only requires the last 255
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        chain.blocks = chain.blocks[-255:]

calculate_base_fee_per_gas

Calculates the base fee per gas for the block.

Parameters

block_gas_limit : Gas limit of the block for which the base fee is being calculated. parent_gas_limit : Gas limit of the parent block. parent_gas_used : Gas used in the parent block. parent_base_fee_per_gas : Base fee per gas of the parent block.

Returns

base_fee_per_gas : Uint Base fee per gas for the block.

def calculate_base_fee_per_gas(block_gas_limit: Uint, ​​parent_gas_limit: Uint, ​​parent_gas_used: Uint, ​​parent_base_fee_per_gas: Uint) -> Uint:
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    """
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    Calculates the base fee per gas for the block.
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    Parameters
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    ----------
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    block_gas_limit :
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        Gas limit of the block for which the base fee is being calculated.
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    parent_gas_limit :
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        Gas limit of the parent block.
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    parent_gas_used :
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        Gas used in the parent block.
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    parent_base_fee_per_gas :
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        Base fee per gas of the parent block.
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    Returns
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    -------
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    base_fee_per_gas : `Uint`
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        Base fee per gas for the block.
234
    """
235
    parent_gas_target = parent_gas_limit // ELASTICITY_MULTIPLIER
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    if not check_gas_limit(block_gas_limit, parent_gas_limit):
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        raise InvalidBlock
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    if parent_gas_used == parent_gas_target:
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        expected_base_fee_per_gas = parent_base_fee_per_gas
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    elif parent_gas_used > parent_gas_target:
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        gas_used_delta = parent_gas_used - parent_gas_target
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        parent_fee_gas_delta = parent_base_fee_per_gas * gas_used_delta
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        target_fee_gas_delta = parent_fee_gas_delta // parent_gas_target
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        base_fee_per_gas_delta = max(
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            target_fee_gas_delta // BASE_FEE_MAX_CHANGE_DENOMINATOR,
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            Uint(1),
250
        )
251
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        expected_base_fee_per_gas = (
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            parent_base_fee_per_gas + base_fee_per_gas_delta
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        )
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    else:
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        gas_used_delta = parent_gas_target - parent_gas_used
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        parent_fee_gas_delta = parent_base_fee_per_gas * gas_used_delta
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        target_fee_gas_delta = parent_fee_gas_delta // parent_gas_target
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        base_fee_per_gas_delta = (
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            target_fee_gas_delta // BASE_FEE_MAX_CHANGE_DENOMINATOR
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        )
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        expected_base_fee_per_gas = (
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            parent_base_fee_per_gas - base_fee_per_gas_delta
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        )
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    return Uint(expected_base_fee_per_gas)

validate_header

Verifies a block header.

In order to consider a block's header valid, the logic for the quantities in the header should match the logic for the block itself. For example the header timestamp should be greater than the block's parent timestamp because the block was created after the parent block. Additionally, the block's number should be directly following the parent block's number since it is the next block in the sequence.

Parameters

chain : History and current state. header : Header to check for correctness.

def validate_header(chain: BlockChain, ​​header: Header) -> None:
273
    """
274
    Verifies a block header.
275
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    In order to consider a block's header valid, the logic for the
277
    quantities in the header should match the logic for the block itself.
278
    For example the header timestamp should be greater than the block's parent
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    timestamp because the block was created *after* the parent block.
280
    Additionally, the block's number should be directly following the parent
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    block's number since it is the next block in the sequence.
282
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    Parameters
284
    ----------
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    chain :
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        History and current state.
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    header :
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        Header to check for correctness.
289
    """
290
    if header.number < Uint(1):
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        raise InvalidBlock
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    parent_header_number = header.number - Uint(1)
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    first_block_number = chain.blocks[0].header.number
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    last_block_number = chain.blocks[-1].header.number
292
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    if (
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        parent_header_number < first_block_number
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        or parent_header_number > last_block_number
307
    ):
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        raise InvalidBlock
309
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    parent_header = chain.blocks[
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        parent_header_number - first_block_number
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    ].header
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    parent_header = chain.blocks[-1].header
294
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    if header.gas_used > header.gas_limit:
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        raise InvalidBlock
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    expected_base_fee_per_gas = calculate_base_fee_per_gas(
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        header.gas_limit,
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        parent_header.gas_limit,
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        parent_header.gas_used,
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        parent_header.base_fee_per_gas,
303
    )
304
    if expected_base_fee_per_gas != header.base_fee_per_gas:
305
        raise InvalidBlock
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    parent_has_ommers = parent_header.ommers_hash != EMPTY_OMMER_HASH
306
    if header.timestamp <= parent_header.timestamp:
307
        raise InvalidBlock
308
    if header.number != parent_header.number + Uint(1):
309
        raise InvalidBlock
310
    if len(header.extra_data) > 32:
311
        raise InvalidBlock
333
334
    block_difficulty = calculate_block_difficulty(
335
        header.number,
336
        header.timestamp,
337
        parent_header.timestamp,
338
        parent_header.difficulty,
339
        parent_has_ommers,
340
    )
341
    if header.difficulty != block_difficulty:
312
    if header.difficulty != 0:
313
        raise InvalidBlock
314
    if header.nonce != b"\x00\x00\x00\x00\x00\x00\x00\x00":
315
        raise InvalidBlock
316
    if header.ommers_hash != EMPTY_OMMER_HASH:
317
        raise InvalidBlock
318
319
    block_parent_hash = keccak256(rlp.encode(parent_header))
320
    if header.parent_hash != block_parent_hash:
346
        raise InvalidBlock
347
348
    validate_proof_of_work(header)
321
        raise InvalidBlock

generate_header_hash_for_pow

Generate rlp hash of the header which is to be used for Proof-of-Work verification.

In other words, the PoW artefacts mix_digest and nonce are ignored while calculating this hash.

A particular PoW is valid for a single hash, that hash is computed by this function. The nonce and mix_digest are omitted from this hash because they are being changed by miners in their search for a sufficient proof-of-work.

Parameters

header : The header object for which the hash is to be generated.

Returns

hash : Hash32 The PoW valid rlp hash of the passed in header.

def generate_header_hash_for_pow(header: Header) -> Hash32:
352
    """
353
    Generate rlp hash of the header which is to be used for Proof-of-Work
354
    verification.
355
356
    In other words, the PoW artefacts `mix_digest` and `nonce` are ignored
357
    while calculating this hash.
358
359
    A particular PoW is valid for a single hash, that hash is computed by
360
    this function. The `nonce` and `mix_digest` are omitted from this hash
361
    because they are being changed by miners in their search for a sufficient
362
    proof-of-work.
363
364
    Parameters
365
    ----------
366
    header :
367
        The header object for which the hash is to be generated.
368
369
    Returns
370
    -------
371
    hash : `Hash32`
372
        The PoW valid rlp hash of the passed in header.
373
    """
374
    header_data_without_pow_artefacts = (
375
        header.parent_hash,
376
        header.ommers_hash,
377
        header.coinbase,
378
        header.state_root,
379
        header.transactions_root,
380
        header.receipt_root,
381
        header.bloom,
382
        header.difficulty,
383
        header.number,
384
        header.gas_limit,
385
        header.gas_used,
386
        header.timestamp,
387
        header.extra_data,
388
        header.base_fee_per_gas,
389
    )
390
391
    return keccak256(rlp.encode(header_data_without_pow_artefacts))

validate_proof_of_work

Validates the Proof of Work constraints.

In order to verify that a miner's proof-of-work is valid for a block, a mix-digest and result are calculated using the hashimoto_light hash function. The mix digest is a hash of the header and the nonce that is passed through and it confirms whether or not proof-of-work was done on the correct block. The result is the actual hash value of the block.

Parameters

header : Header of interest.

def validate_proof_of_work(header: Header) -> None:
395
    """
396
    Validates the Proof of Work constraints.
397
398
    In order to verify that a miner's proof-of-work is valid for a block, a
399
    ``mix-digest`` and ``result`` are calculated using the ``hashimoto_light``
400
    hash function. The mix digest is a hash of the header and the nonce that
401
    is passed through and it confirms whether or not proof-of-work was done
402
    on the correct block. The result is the actual hash value of the block.
403
404
    Parameters
405
    ----------
406
    header :
407
        Header of interest.
408
    """
409
    header_hash = generate_header_hash_for_pow(header)
410
    # TODO: Memoize this somewhere and read from that data instead of
411
    # calculating cache for every block validation.
412
    cache = generate_cache(header.number)
413
    mix_digest, result = hashimoto_light(
414
        header_hash, header.nonce, cache, dataset_size(header.number)
415
    )
416
    if mix_digest != header.mix_digest:
417
        raise InvalidBlock
418
419
    limit = Uint(U256.MAX_VALUE) + Uint(1)
420
    if Uint.from_be_bytes(result) > (limit // header.difficulty):
421
        raise InvalidBlock

check_transaction

Check if the transaction is includable in the block.

Parameters

block_env : The block scoped environment. block_output : The block output for the current block. tx : The transaction.

Returns

sender_address : The sender of the transaction. effective_gas_price : The price to charge for gas when the transaction is executed.

Raises

InvalidBlock : If the transaction is not includable. GasUsedExceedsLimitError : If the gas used by the transaction exceeds the block's gas limit. NonceMismatchError : If the nonce of the transaction is not equal to the sender's nonce. InsufficientBalanceError : If the sender's balance is not enough to pay for the transaction. InvalidSenderError : If the transaction is from an address that does not exist anymore. PriorityFeeGreaterThanMaxFeeError:PriorityFeeGreaterThanMaxFeeError : If the priority fee is greater than the maximum fee per gas. InsufficientMaxFeePerGasError : If the maximum fee per gas is insufficient for the transaction.

def check_transaction(block_env: ethereum.gray_glacier.vm.BlockEnvironmentethereum.paris.vm.BlockEnvironment, ​​block_output: ethereum.gray_glacier.vm.BlockOutputethereum.paris.vm.BlockOutput, ​​tx: Transaction) -> Tuple[Address, Uint]:
329
    """
330
    Check if the transaction is includable in the block.
331
332
    Parameters
333
    ----------
334
    block_env :
335
        The block scoped environment.
336
    block_output :
337
        The block output for the current block.
338
    tx :
339
        The transaction.
340
341
    Returns
342
    -------
343
    sender_address :
344
        The sender of the transaction.
345
    effective_gas_price :
346
        The price to charge for gas when the transaction is executed.
347
348
    Raises
349
    ------
350
    InvalidBlock :
351
        If the transaction is not includable.
352
    GasUsedExceedsLimitError :
353
        If the gas used by the transaction exceeds the block's gas limit.
354
    NonceMismatchError :
355
        If the nonce of the transaction is not equal to the sender's nonce.
356
    InsufficientBalanceError :
357
        If the sender's balance is not enough to pay for the transaction.
358
    InvalidSenderError :
359
        If the transaction is from an address that does not exist anymore.
460
    PriorityFeeGreaterThanMaxFeeError:
360
    PriorityFeeGreaterThanMaxFeeError :
361
        If the priority fee is greater than the maximum fee per gas.
362
    InsufficientMaxFeePerGasError :
363
        If the maximum fee per gas is insufficient for the transaction.
364
    """
365
    gas_available = block_env.block_gas_limit - block_output.block_gas_used
366
    if tx.gas > gas_available:
367
        raise GasUsedExceedsLimitError("gas used exceeds limit")
368
    sender_address = recover_sender(block_env.chain_id, tx)
369
    sender_account = get_account(block_env.state, sender_address)
370
371
    if isinstance(tx, FeeMarketTransaction):
372
        if tx.max_fee_per_gas < tx.max_priority_fee_per_gas:
373
            raise PriorityFeeGreaterThanMaxFeeError(
374
                "priority fee greater than max fee"
375
            )
376
        if tx.max_fee_per_gas < block_env.base_fee_per_gas:
377
            raise InsufficientMaxFeePerGasError(
378
                tx.max_fee_per_gas, block_env.base_fee_per_gas
379
            )
380
381
        priority_fee_per_gas = min(
382
            tx.max_priority_fee_per_gas,
383
            tx.max_fee_per_gas - block_env.base_fee_per_gas,
384
        )
385
        effective_gas_price = priority_fee_per_gas + block_env.base_fee_per_gas
386
        max_gas_fee = tx.gas * tx.max_fee_per_gas
387
    else:
388
        if tx.gas_price < block_env.base_fee_per_gas:
389
            raise InvalidBlock
390
        effective_gas_price = tx.gas_price
391
        max_gas_fee = tx.gas * tx.gas_price
392
393
    if sender_account.nonce > Uint(tx.nonce):
394
        raise NonceMismatchError("nonce too low")
395
    elif sender_account.nonce < Uint(tx.nonce):
396
        raise NonceMismatchError("nonce too high")
397
    if Uint(sender_account.balance) < max_gas_fee + Uint(tx.value):
398
        raise InsufficientBalanceError("insufficient sender balance")
399
    if sender_account.code:
400
        raise InvalidSenderError("not EOA")
401
402
    return sender_address, effective_gas_price

make_receipt

Make the receipt for a transaction that was executed.

Parameters

tx : The executed transaction. error : Error in the top level frame of the transaction, if any. cumulative_gas_used : The total gas used so far in the block after the transaction was executed. logs : The logs produced by the transaction.

Returns

receipt : The receipt for the transaction.

def make_receipt(tx: Transaction, ​​error: Optional[EthereumException], ​​cumulative_gas_used: Uint, ​​logs: Tuple[Log, ...]) -> Bytes | Receipt:
411
    """
412
    Make the receipt for a transaction that was executed.
413
414
    Parameters
415
    ----------
416
    tx :
417
        The executed transaction.
418
    error :
419
        Error in the top level frame of the transaction, if any.
420
    cumulative_gas_used :
421
        The total gas used so far in the block after the transaction was
422
        executed.
423
    logs :
424
        The logs produced by the transaction.
425
426
    Returns
427
    -------
428
    receipt :
429
        The receipt for the transaction.
430
    """
431
    receipt = Receipt(
432
        succeeded=error is None,
433
        cumulative_gas_used=cumulative_gas_used,
434
        bloom=logs_bloom(logs),
435
        logs=logs,
436
    )
437
438
    return encode_receipt(tx, receipt)

apply_body

Executes a block.

Many of the contents of a block are stored in data structures called tries. There is a transactions trie which is similar to a ledger of the transactions stored in the current block. There is also a receipts trie which stores the results of executing a transaction, like the post state and gas used. This function creates and executes the block that is to be added to the chain.

Parameters

block_env : The block scoped environment. transactions : Transactions included in the block. ommers : Headers of ancestor blocks which are not direct parents (formerly uncles.)

Returns

block_output : The block output for the current block.

def apply_body(block_env: ethereum.gray_glacier.vm.BlockEnvironmentethereum.paris.vm.BlockEnvironment, ​​transactions: Tuple[LegacyTransaction | Bytes, ...], ​​ommers: Tuple[Header, ...]) -> ethereum.gray_glacier.vm.BlockOutputethereum.paris.vm.BlockOutput:
445
    """
446
    Executes a block.
447
448
    Many of the contents of a block are stored in data structures called
449
    tries. There is a transactions trie which is similar to a ledger of the
450
    transactions stored in the current block. There is also a receipts trie
451
    which stores the results of executing a transaction, like the post state
452
    and gas used. This function creates and executes the block that is to be
453
    added to the chain.
454
455
    Parameters
456
    ----------
457
    block_env :
458
        The block scoped environment.
459
    transactions :
460
        Transactions included in the block.
562
    ommers :
563
        Headers of ancestor blocks which are not direct parents (formerly
564
        uncles.)
461
462
    Returns
463
    -------
464
    block_output :
465
        The block output for the current block.
466
    """
467
    block_output = vm.BlockOutput()
468
469
    for i, tx in enumerate(map(decode_transaction, transactions)):
470
        process_transaction(block_env, block_output, tx, Uint(i))
471
576
    pay_rewards(block_env.state, block_env.number, block_env.coinbase, ommers)
577
472
    return block_output

validate_ommers

Validates the ommers mentioned in the block.

An ommer block is a block that wasn't canonically added to the blockchain because it wasn't validated as fast as the canonical block but was mined at the same time.

To be considered valid, the ommers must adhere to the rules defined in the Ethereum protocol. The maximum amount of ommers is 2 per block and there cannot be duplicate ommers in a block. Many of the other ommer constraints are listed in the in-line comments of this function.

Parameters

ommers : List of ommers mentioned in the current block. block_header: The header of current block. chain : History and current state.

def validate_ommers(ommers: Tuple[Header, ...], ​​block_header: Header, ​​chain: BlockChain) -> None:
584
    """
585
    Validates the ommers mentioned in the block.
586
587
    An ommer block is a block that wasn't canonically added to the
588
    blockchain because it wasn't validated as fast as the canonical block
589
    but was mined at the same time.
590
591
    To be considered valid, the ommers must adhere to the rules defined in
592
    the Ethereum protocol. The maximum amount of ommers is 2 per block and
593
    there cannot be duplicate ommers in a block. Many of the other ommer
594
    constraints are listed in the in-line comments of this function.
595
596
    Parameters
597
    ----------
598
    ommers :
599
        List of ommers mentioned in the current block.
600
    block_header:
601
        The header of current block.
602
    chain :
603
        History and current state.
604
    """
605
    block_hash = keccak256(rlp.encode(block_header))
606
    if keccak256(rlp.encode(ommers)) != block_header.ommers_hash:
607
        raise InvalidBlock
608
609
    if len(ommers) == 0:
610
        # Nothing to validate
611
        return
612
613
    # Check that each ommer satisfies the constraints of a header
614
    for ommer in ommers:
615
        if Uint(1) > ommer.number or ommer.number >= block_header.number:
616
            raise InvalidBlock
617
        validate_header(chain, ommer)
618
    if len(ommers) > 2:
619
        raise InvalidBlock
620
621
    ommers_hashes = [keccak256(rlp.encode(ommer)) for ommer in ommers]
622
    if len(ommers_hashes) != len(set(ommers_hashes)):
623
        raise InvalidBlock
624
625
    recent_canonical_blocks = chain.blocks[-(MAX_OMMER_DEPTH + Uint(1)) :]
626
    recent_canonical_block_hashes = {
627
        keccak256(rlp.encode(block.header))
628
        for block in recent_canonical_blocks
629
    }
630
    recent_ommers_hashes: Set[Hash32] = set()
631
    for block in recent_canonical_blocks:
632
        recent_ommers_hashes = recent_ommers_hashes.union(
633
            {keccak256(rlp.encode(ommer)) for ommer in block.ommers}
634
        )
635
636
    for ommer_index, ommer in enumerate(ommers):
637
        ommer_hash = ommers_hashes[ommer_index]
638
        if ommer_hash == block_hash:
639
            raise InvalidBlock
640
        if ommer_hash in recent_canonical_block_hashes:
641
            raise InvalidBlock
642
        if ommer_hash in recent_ommers_hashes:
643
            raise InvalidBlock
644
645
        # Ommer age with respect to the current block. For example, an age of
646
        # 1 indicates that the ommer is a sibling of previous block.
647
        ommer_age = block_header.number - ommer.number
648
        if Uint(1) > ommer_age or ommer_age > MAX_OMMER_DEPTH:
649
            raise InvalidBlock
650
        if ommer.parent_hash not in recent_canonical_block_hashes:
651
            raise InvalidBlock
652
        if ommer.parent_hash == block_header.parent_hash:
653
            raise InvalidBlock

pay_rewards

Pay rewards to the block miner as well as the ommers miners.

The miner of the canonical block is rewarded with the predetermined block reward, BLOCK_REWARD, plus a variable award based off of the number of ommer blocks that were mined around the same time, and included in the canonical block's header. An ommer block is a block that wasn't added to the canonical blockchain because it wasn't validated as fast as the accepted block but was mined at the same time. Although not all blocks that are mined are added to the canonical chain, miners are still paid a reward for their efforts. This reward is called an ommer reward and is calculated based on the number associated with the ommer block that they mined.

Parameters

state : Current account state. block_number : Position of the block within the chain. coinbase : Address of account which receives block reward and transaction fees. ommers : List of ommers mentioned in the current block.

def pay_rewards(state: State, ​​block_number: Uint, ​​coinbase: Address, ​​ommers: Tuple[Header, ...]) -> None:
662
    """
663
    Pay rewards to the block miner as well as the ommers miners.
664
665
    The miner of the canonical block is rewarded with the predetermined
666
    block reward, ``BLOCK_REWARD``, plus a variable award based off of the
667
    number of ommer blocks that were mined around the same time, and included
668
    in the canonical block's header. An ommer block is a block that wasn't
669
    added to the canonical blockchain because it wasn't validated as fast as
670
    the accepted block but was mined at the same time. Although not all blocks
671
    that are mined are added to the canonical chain, miners are still paid a
672
    reward for their efforts. This reward is called an ommer reward and is
673
    calculated based on the number associated with the ommer block that they
674
    mined.
675
676
    Parameters
677
    ----------
678
    state :
679
        Current account state.
680
    block_number :
681
        Position of the block within the chain.
682
    coinbase :
683
        Address of account which receives block reward and transaction fees.
684
    ommers :
685
        List of ommers mentioned in the current block.
686
    """
687
    ommer_count = U256(len(ommers))
688
    miner_reward = BLOCK_REWARD + (ommer_count * (BLOCK_REWARD // U256(32)))
689
    create_ether(state, coinbase, miner_reward)
690
691
    for ommer in ommers:
692
        # Ommer age with respect to the current block.
693
        ommer_age = U256(block_number - ommer.number)
694
        ommer_miner_reward = ((U256(8) - ommer_age) * BLOCK_REWARD) // U256(8)
695
        create_ether(state, ommer.coinbase, ommer_miner_reward)

process_transaction

Execute a transaction against the provided environment.

This function processes the actions needed to execute a transaction. It decrements the sender's account balance after calculating the gas fee and refunds them the proper amount after execution. Calling contracts, deploying code, and incrementing nonces are all examples of actions that happen within this function or from a call made within this function.

Accounts that are marked for deletion are processed and destroyed after execution.

Parameters

block_env : Environment for the Ethereum Virtual Machine. block_output : The block output for the current block. tx : Transaction to execute. index: Index of the transaction in the block.

def process_transaction(block_env: ethereum.gray_glacier.vm.BlockEnvironmentethereum.paris.vm.BlockEnvironment, ​​block_output: ethereum.gray_glacier.vm.BlockOutputethereum.paris.vm.BlockOutput, ​​tx: Transaction, ​​index: Uint) -> None:
481
    """
482
    Execute a transaction against the provided environment.
483
484
    This function processes the actions needed to execute a transaction.
485
    It decrements the sender's account balance after calculating the gas fee
486
    and refunds them the proper amount after execution. Calling contracts,
487
    deploying code, and incrementing nonces are all examples of actions that
488
    happen within this function or from a call made within this function.
489
490
    Accounts that are marked for deletion are processed and destroyed after
491
    execution.
492
493
    Parameters
494
    ----------
495
    block_env :
496
        Environment for the Ethereum Virtual Machine.
497
    block_output :
498
        The block output for the current block.
499
    tx :
500
        Transaction to execute.
501
    index:
502
        Index of the transaction in the block.
503
    """
504
    trie_set(
505
        block_output.transactions_trie,
506
        rlp.encode(index),
507
        encode_transaction(tx),
508
    )
509
510
    intrinsic_gas = validate_transaction(tx)
511
512
    (
513
        sender,
514
        effective_gas_price,
515
    ) = check_transaction(
516
        block_env=block_env,
517
        block_output=block_output,
518
        tx=tx,
519
    )
520
521
    sender_account = get_account(block_env.state, sender)
522
523
    effective_gas_fee = tx.gas * effective_gas_price
524
525
    gas = tx.gas - intrinsic_gas
526
    increment_nonce(block_env.state, sender)
527
528
    sender_balance_after_gas_fee = (
529
        Uint(sender_account.balance) - effective_gas_fee
530
    )
531
    set_account_balance(
532
        block_env.state, sender, U256(sender_balance_after_gas_fee)
533
    )
534
535
    access_list_addresses = set()
536
    access_list_storage_keys = set()
537
    if isinstance(tx, (AccessListTransaction, FeeMarketTransaction)):
538
        for access in tx.access_list:
539
            access_list_addresses.add(access.account)
540
            for slot in access.slots:
541
                access_list_storage_keys.add((access.account, slot))
542
543
    tx_env = vm.TransactionEnvironment(
544
        origin=sender,
545
        gas_price=effective_gas_price,
546
        gas=gas,
547
        access_list_addresses=access_list_addresses,
548
        access_list_storage_keys=access_list_storage_keys,
549
        index_in_block=index,
550
        tx_hash=get_transaction_hash(encode_transaction(tx)),
551
    )
552
553
    message = prepare_message(block_env, tx_env, tx)
554
555
    tx_output = process_message_call(message)
556
557
    tx_gas_used_before_refund = tx.gas - tx_output.gas_left
558
    tx_gas_refund = min(
559
        tx_gas_used_before_refund // Uint(5), Uint(tx_output.refund_counter)
560
    )
561
    tx_gas_used_after_refund = tx_gas_used_before_refund - tx_gas_refund
562
    tx_gas_left = tx.gas - tx_gas_used_after_refund
563
    gas_refund_amount = tx_gas_left * effective_gas_price
564
565
    # For non-1559 transactions effective_gas_price == tx.gas_price
566
    priority_fee_per_gas = effective_gas_price - block_env.base_fee_per_gas
567
    transaction_fee = tx_gas_used_after_refund * priority_fee_per_gas
568
569
    # refund gas
570
    sender_balance_after_refund = get_account(
571
        block_env.state, sender
572
    ).balance + U256(gas_refund_amount)
573
    set_account_balance(block_env.state, sender, sender_balance_after_refund)
574
575
    # transfer miner fees
576
    coinbase_balance_after_mining_fee = get_account(
577
        block_env.state, block_env.coinbase
578
    ).balance + U256(transaction_fee)
802
    if coinbase_balance_after_mining_fee != 0:
803
        set_account_balance(
804
            block_env.state,
805
            block_env.coinbase,
806
            coinbase_balance_after_mining_fee,
807
        )
808
    elif account_exists_and_is_empty(block_env.state, block_env.coinbase):
809
        destroy_account(block_env.state, block_env.coinbase)
579
    set_account_balance(
580
        block_env.state,
581
        block_env.coinbase,
582
        coinbase_balance_after_mining_fee,
583
    )
584
585
    for address in tx_output.accounts_to_delete:
586
        destroy_account(block_env.state, address)
813
814
    destroy_touched_empty_accounts(block_env.state, tx_output.touched_accounts)
587
588
    block_output.block_gas_used += tx_gas_used_after_refund
589
590
    receipt = make_receipt(
591
        tx, tx_output.error, block_output.block_gas_used, tx_output.logs
592
    )
593
594
    receipt_key = rlp.encode(Uint(index))
595
    block_output.receipt_keys += (receipt_key,)
596
597
    trie_set(
598
        block_output.receipts_trie,
599
        receipt_key,
600
        receipt,
601
    )
602
603
    block_output.block_logs += tx_output.logs

check_gas_limit

Validates the gas limit for a block.

The bounds of the gas limit, max_adjustment_delta, is set as the quotient of the parent block's gas limit and the GAS_LIMIT_ADJUSTMENT_FACTOR. Therefore, if the gas limit that is passed through as a parameter is greater than or equal to the sum of the parent's gas and the adjustment delta then the limit for gas is too high and fails this function's check. Similarly, if the limit is less than or equal to the difference of the parent's gas and the adjustment delta or the predefined GAS_LIMIT_MINIMUM then this function's check fails because the gas limit doesn't allow for a sufficient or reasonable amount of gas to be used on a block.

Parameters

gas_limit : Gas limit to validate.

parent_gas_limit : Gas limit of the parent block.

Returns

check : bool True if gas limit constraints are satisfied, False otherwise.

def check_gas_limit(gas_limit: Uint, ​​parent_gas_limit: Uint) -> bool:
607
    """
608
    Validates the gas limit for a block.
609
610
    The bounds of the gas limit, ``max_adjustment_delta``, is set as the
611
    quotient of the parent block's gas limit and the
612
    ``GAS_LIMIT_ADJUSTMENT_FACTOR``. Therefore, if the gas limit that is
613
    passed through as a parameter is greater than or equal to the *sum* of
614
    the parent's gas and the adjustment delta then the limit for gas is too
615
    high and fails this function's check. Similarly, if the limit is less
616
    than or equal to the *difference* of the parent's gas and the adjustment
617
    delta *or* the predefined ``GAS_LIMIT_MINIMUM`` then this function's
618
    check fails because the gas limit doesn't allow for a sufficient or
619
    reasonable amount of gas to be used on a block.
620
621
    Parameters
622
    ----------
623
    gas_limit :
624
        Gas limit to validate.
625
626
    parent_gas_limit :
627
        Gas limit of the parent block.
628
629
    Returns
630
    -------
631
    check : `bool`
632
        True if gas limit constraints are satisfied, False otherwise.
633
    """
634
    max_adjustment_delta = parent_gas_limit // GAS_LIMIT_ADJUSTMENT_FACTOR
635
    if gas_limit >= parent_gas_limit + max_adjustment_delta:
636
        return False
637
    if gas_limit <= parent_gas_limit - max_adjustment_delta:
638
        return False
639
    if gas_limit < GAS_LIMIT_MINIMUM:
640
        return False
641
642
    return True

calculate_block_difficulty

Computes difficulty of a block using its header and parent header.

The difficulty is determined by the time the block was created after its parent. The offset is calculated using the parent block's difficulty, parent_difficulty, and the timestamp between blocks. This offset is then added to the parent difficulty and is stored as the difficulty variable. If the time between the block and its parent is too short, the offset will result in a positive number thus making the sum of parent_difficulty and offset to be a greater value in order to avoid mass forking. But, if the time is long enough, then the offset results in a negative value making the block less difficult than its parent.

The base standard for a block's difficulty is the predefined value set for the genesis block since it has no parent. So, a block can't be less difficult than the genesis block, therefore each block's difficulty is set to the maximum value between the calculated difficulty and the GENESIS_DIFFICULTY.

Parameters

block_number : Block number of the block. block_timestamp : Timestamp of the block. parent_timestamp : Timestamp of the parent block. parent_difficulty : difficulty of the parent block. parent_has_ommers: does the parent have ommers.

Returns

difficulty : ethereum.base_types.Uint Computed difficulty for a block.

def calculate_block_difficulty(block_number: Uint, ​​block_timestamp: U256, ​​parent_timestamp: U256, ​​parent_difficulty: Uint, ​​parent_has_ommers: bool) -> Uint:
880
    """
881
    Computes difficulty of a block using its header and parent header.
882
883
    The difficulty is determined by the time the block was created after its
884
    parent. The ``offset`` is calculated using the parent block's difficulty,
885
    ``parent_difficulty``, and the timestamp between blocks. This offset is
886
    then added to the parent difficulty and is stored as the ``difficulty``
887
    variable. If the time between the block and its parent is too short, the
888
    offset will result in a positive number thus making the sum of
889
    ``parent_difficulty`` and ``offset`` to be a greater value in order to
890
    avoid mass forking. But, if the time is long enough, then the offset
891
    results in a negative value making the block less difficult than
892
    its parent.
893
894
    The base standard for a block's difficulty is the predefined value
895
    set for the genesis block since it has no parent. So, a block
896
    can't be less difficult than the genesis block, therefore each block's
897
    difficulty is set to the maximum value between the calculated
898
    difficulty and the ``GENESIS_DIFFICULTY``.
899
900
    Parameters
901
    ----------
902
    block_number :
903
        Block number of the block.
904
    block_timestamp :
905
        Timestamp of the block.
906
    parent_timestamp :
907
        Timestamp of the parent block.
908
    parent_difficulty :
909
        difficulty of the parent block.
910
    parent_has_ommers:
911
        does the parent have ommers.
912
913
    Returns
914
    -------
915
    difficulty : `ethereum.base_types.Uint`
916
        Computed difficulty for a block.
917
    """
918
    offset = (
919
        int(parent_difficulty)
920
        // 2048
921
        * max(
922
            (2 if parent_has_ommers else 1)
923
            - int(block_timestamp - parent_timestamp) // 9,
924
            -99,
925
        )
926
    )
927
    difficulty = int(parent_difficulty) + offset
928
    # Historical Note: The difficulty bomb was not present in Ethereum at the
929
    # start of Frontier, but was added shortly after launch. However since the
930
    # bomb has no effect prior to block 200000 we pretend it existed from
931
    # genesis.
932
    # See https://github.com/ethereum/go-ethereum/pull/1588
933
    num_bomb_periods = ((int(block_number) - BOMB_DELAY_BLOCKS) // 100000) - 2
934
    if num_bomb_periods >= 0:
935
        difficulty += 2**num_bomb_periods
936
937
    # Some clients raise the difficulty to `MINIMUM_DIFFICULTY` prior to adding
938
    # the bomb. This bug does not matter because the difficulty is always much
939
    # greater than `MINIMUM_DIFFICULTY` on Mainnet.
940
    return Uint(max(difficulty, int(MINIMUM_DIFFICULTY)))