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.
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    When forks need to implement an irregular state transition, this function
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    is used to handle the irregularity. See the :ref:`DAO Fork <dao-fork>` for
89
    an example.
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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.
100
    """
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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
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    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
157
    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`.
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    """
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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)
205
    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.
235
    """
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    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),
251
        )
252
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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:
274
    """
275
    Verifies a block header.
276
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    In order to consider a block's header valid, the logic for the
278
    quantities in the header should match the logic for the block itself.
279
    For example the header timestamp should be greater than the block's parent
280
    timestamp because the block was created *after* the parent block.
281
    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.
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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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    header :
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        Header to check for correctness.
290
    """
291
    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
293
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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
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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
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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,
304
    )
305
    if expected_base_fee_per_gas != header.base_fee_per_gas:
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        raise InvalidBlock
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    parent_has_ommers = parent_header.ommers_hash != EMPTY_OMMER_HASH
307
    if header.timestamp <= parent_header.timestamp:
308
        raise InvalidBlock
309
    if header.number != parent_header.number + Uint(1):
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        raise InvalidBlock
311
    if len(header.extra_data) > 32:
312
        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:
313
    if header.difficulty != 0:
314
        raise InvalidBlock
315
    if header.nonce != b"\x00\x00\x00\x00\x00\x00\x00\x00":
316
        raise InvalidBlock
317
    if header.ommers_hash != EMPTY_OMMER_HASH:
318
        raise InvalidBlock
319
320
    block_parent_hash = keccak256(rlp.encode(parent_header))
321
    if header.parent_hash != block_parent_hash:
346
        raise InvalidBlock
347
348
    validate_proof_of_work(header)
322
        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]:
330
    """
331
    Check if the transaction is includable in the block.
332
333
    Parameters
334
    ----------
335
    block_env :
336
        The block scoped environment.
337
    block_output :
338
        The block output for the current block.
339
    tx :
340
        The transaction.
341
342
    Returns
343
    -------
344
    sender_address :
345
        The sender of the transaction.
346
    effective_gas_price :
347
        The price to charge for gas when the transaction is executed.
348
349
    Raises
350
    ------
351
    InvalidBlock :
352
        If the transaction is not includable.
353
    GasUsedExceedsLimitError :
354
        If the gas used by the transaction exceeds the block's gas limit.
355
    NonceMismatchError :
356
        If the nonce of the transaction is not equal to the sender's nonce.
357
    InsufficientBalanceError :
358
        If the sender's balance is not enough to pay for the transaction.
359
    InvalidSenderError :
360
        If the transaction is from an address that does not exist anymore.
460
    PriorityFeeGreaterThanMaxFeeError:
361
    PriorityFeeGreaterThanMaxFeeError :
362
        If the priority fee is greater than the maximum fee per gas.
363
    InsufficientMaxFeePerGasError :
364
        If the maximum fee per gas is insufficient for the transaction.
365
    """
366
    gas_available = block_env.block_gas_limit - block_output.block_gas_used
367
    if tx.gas > gas_available:
368
        raise GasUsedExceedsLimitError("gas used exceeds limit")
369
    sender_address = recover_sender(block_env.chain_id, tx)
370
    sender_account = get_account(block_env.state, sender_address)
371
372
    if isinstance(tx, FeeMarketTransaction):
373
        if tx.max_fee_per_gas < tx.max_priority_fee_per_gas:
374
            raise PriorityFeeGreaterThanMaxFeeError(
375
                "priority fee greater than max fee"
376
            )
377
        if tx.max_fee_per_gas < block_env.base_fee_per_gas:
378
            raise InsufficientMaxFeePerGasError(
379
                tx.max_fee_per_gas, block_env.base_fee_per_gas
380
            )
381
382
        priority_fee_per_gas = min(
383
            tx.max_priority_fee_per_gas,
384
            tx.max_fee_per_gas - block_env.base_fee_per_gas,
385
        )
386
        effective_gas_price = priority_fee_per_gas + block_env.base_fee_per_gas
387
        max_gas_fee = tx.gas * tx.max_fee_per_gas
388
    else:
389
        if tx.gas_price < block_env.base_fee_per_gas:
390
            raise InvalidBlock
391
        effective_gas_price = tx.gas_price
392
        max_gas_fee = tx.gas * tx.gas_price
393
394
    if sender_account.nonce > Uint(tx.nonce):
395
        raise NonceMismatchError("nonce too low")
396
    elif sender_account.nonce < Uint(tx.nonce):
397
        raise NonceMismatchError("nonce too high")
398
    if Uint(sender_account.balance) < max_gas_fee + Uint(tx.value):
399
        raise InsufficientBalanceError("insufficient sender balance")
400
    if sender_account.code:
401
        raise InvalidSenderError("not EOA")
402
403
    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:
412
    """
413
    Make the receipt for a transaction that was executed.
414
415
    Parameters
416
    ----------
417
    tx :
418
        The executed transaction.
419
    error :
420
        Error in the top level frame of the transaction, if any.
421
    cumulative_gas_used :
422
        The total gas used so far in the block after the transaction was
423
        executed.
424
    logs :
425
        The logs produced by the transaction.
426
427
    Returns
428
    -------
429
    receipt :
430
        The receipt for the transaction.
431
    """
432
    receipt = Receipt(
433
        succeeded=error is None,
434
        cumulative_gas_used=cumulative_gas_used,
435
        bloom=logs_bloom(logs),
436
        logs=logs,
437
    )
438
439
    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:
446
    """
447
    Executes a block.
448
449
    Many of the contents of a block are stored in data structures called
450
    tries. There is a transactions trie which is similar to a ledger of the
451
    transactions stored in the current block. There is also a receipts trie
452
    which stores the results of executing a transaction, like the post state
453
    and gas used. This function creates and executes the block that is to be
454
    added to the chain.
455
456
    Parameters
457
    ----------
458
    block_env :
459
        The block scoped environment.
460
    transactions :
461
        Transactions included in the block.
562
    ommers :
563
        Headers of ancestor blocks which are not direct parents (formerly
564
        uncles.)
462
463
    Returns
464
    -------
465
    block_output :
466
        The block output for the current block.
467
    """
468
    block_output = vm.BlockOutput()
469
470
    for i, tx in enumerate(map(decode_transaction, transactions)):
471
        process_transaction(block_env, block_output, tx, Uint(i))
472
576
    pay_rewards(block_env.state, block_env.number, block_env.coinbase, ommers)
577
473
    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 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:
482
    """
483
    Execute a transaction against the provided environment.
484
485
    This function processes the actions needed to execute a transaction.
486
    It decrements the sender's account after calculating the gas fee and
487
    refunds them the proper amount after execution. Calling contracts,
488
    deploying code, and incrementing nonces are all examples of actions that
489
    happen within this function or from a call made within this function.
490
491
    Accounts that are marked for deletion are processed and destroyed after
492
    execution.
493
494
    Parameters
495
    ----------
496
    block_env :
497
        Environment for the Ethereum Virtual Machine.
498
    block_output :
499
        The block output for the current block.
500
    tx :
501
        Transaction to execute.
502
    index:
503
        Index of the transaction in the block.
504
    """
505
    trie_set(
506
        block_output.transactions_trie,
507
        rlp.encode(index),
508
        encode_transaction(tx),
509
    )
510
511
    intrinsic_gas = validate_transaction(tx)
512
513
    (
514
        sender,
515
        effective_gas_price,
516
    ) = check_transaction(
517
        block_env=block_env,
518
        block_output=block_output,
519
        tx=tx,
520
    )
521
522
    sender_account = get_account(block_env.state, sender)
523
524
    effective_gas_fee = tx.gas * effective_gas_price
525
526
    gas = tx.gas - intrinsic_gas
527
    increment_nonce(block_env.state, sender)
528
529
    sender_balance_after_gas_fee = (
530
        Uint(sender_account.balance) - effective_gas_fee
531
    )
532
    set_account_balance(
533
        block_env.state, sender, U256(sender_balance_after_gas_fee)
534
    )
535
536
    access_list_addresses = set()
537
    access_list_storage_keys = set()
538
    if isinstance(tx, (AccessListTransaction, FeeMarketTransaction)):
539
        for access in tx.access_list:
540
            access_list_addresses.add(access.account)
541
            for slot in access.slots:
542
                access_list_storage_keys.add((access.account, slot))
543
544
    tx_env = vm.TransactionEnvironment(
545
        origin=sender,
546
        gas_price=effective_gas_price,
547
        gas=gas,
548
        access_list_addresses=access_list_addresses,
549
        access_list_storage_keys=access_list_storage_keys,
550
        index_in_block=index,
551
        tx_hash=get_transaction_hash(encode_transaction(tx)),
552
        traces=[],
553
    )
554
555
    message = prepare_message(block_env, tx_env, tx)
556
557
    tx_output = process_message_call(message)
558
559
    tx_gas_used_before_refund = tx.gas - tx_output.gas_left
560
    tx_gas_refund = min(
561
        tx_gas_used_before_refund // Uint(5), Uint(tx_output.refund_counter)
562
    )
563
    tx_gas_used_after_refund = tx_gas_used_before_refund - tx_gas_refund
564
    tx_gas_left = tx.gas - tx_gas_used_after_refund
565
    gas_refund_amount = tx_gas_left * effective_gas_price
566
567
    # For non-1559 transactions effective_gas_price == tx.gas_price
568
    priority_fee_per_gas = effective_gas_price - block_env.base_fee_per_gas
569
    transaction_fee = tx_gas_used_after_refund * priority_fee_per_gas
570
571
    # refund gas
572
    sender_balance_after_refund = get_account(
573
        block_env.state, sender
574
    ).balance + U256(gas_refund_amount)
575
    set_account_balance(block_env.state, sender, sender_balance_after_refund)
576
577
    # transfer miner fees
578
    coinbase_balance_after_mining_fee = get_account(
579
        block_env.state, block_env.coinbase
580
    ).balance + U256(transaction_fee)
581
    if coinbase_balance_after_mining_fee != 0:
582
        set_account_balance(
583
            block_env.state,
584
            block_env.coinbase,
585
            coinbase_balance_after_mining_fee,
586
        )
587
    elif account_exists_and_is_empty(block_env.state, block_env.coinbase):
588
        destroy_account(block_env.state, block_env.coinbase)
589
590
    for address in tx_output.accounts_to_delete:
591
        destroy_account(block_env.state, address)
592
815
    destroy_touched_empty_accounts(block_env.state, tx_output.touched_accounts)
816
593
    block_output.block_gas_used += tx_gas_used_after_refund
594
595
    receipt = make_receipt(
596
        tx, tx_output.error, block_output.block_gas_used, tx_output.logs
597
    )
598
599
    receipt_key = rlp.encode(Uint(index))
600
    block_output.receipt_keys += (receipt_key,)
601
602
    trie_set(
603
        block_output.receipts_trie,
604
        receipt_key,
605
        receipt,
606
    )
607
608
    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:
612
    """
613
    Validates the gas limit for a block.
614
615
    The bounds of the gas limit, ``max_adjustment_delta``, is set as the
616
    quotient of the parent block's gas limit and the
617
    ``GAS_LIMIT_ADJUSTMENT_FACTOR``. Therefore, if the gas limit that is
618
    passed through as a parameter is greater than or equal to the *sum* of
619
    the parent's gas and the adjustment delta then the limit for gas is too
620
    high and fails this function's check. Similarly, if the limit is less
621
    than or equal to the *difference* of the parent's gas and the adjustment
622
    delta *or* the predefined ``GAS_LIMIT_MINIMUM`` then this function's
623
    check fails because the gas limit doesn't allow for a sufficient or
624
    reasonable amount of gas to be used on a block.
625
626
    Parameters
627
    ----------
628
    gas_limit :
629
        Gas limit to validate.
630
631
    parent_gas_limit :
632
        Gas limit of the parent block.
633
634
    Returns
635
    -------
636
    check : `bool`
637
        True if gas limit constraints are satisfied, False otherwise.
638
    """
639
    max_adjustment_delta = parent_gas_limit // GAS_LIMIT_ADJUSTMENT_FACTOR
640
    if gas_limit >= parent_gas_limit + max_adjustment_delta:
641
        return False
642
    if gas_limit <= parent_gas_limit - max_adjustment_delta:
643
        return False
644
    if gas_limit < GAS_LIMIT_MINIMUM:
645
        return False
646
647
    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:
881
    """
882
    Computes difficulty of a block using its header and parent header.
883
884
    The difficulty is determined by the time the block was created after its
885
    parent. The ``offset`` is calculated using the parent block's difficulty,
886
    ``parent_difficulty``, and the timestamp between blocks. This offset is
887
    then added to the parent difficulty and is stored as the ``difficulty``
888
    variable. If the time between the block and its parent is too short, the
889
    offset will result in a positive number thus making the sum of
890
    ``parent_difficulty`` and ``offset`` to be a greater value in order to
891
    avoid mass forking. But, if the time is long enough, then the offset
892
    results in a negative value making the block less difficult than
893
    its parent.
894
895
    The base standard for a block's difficulty is the predefined value
896
    set for the genesis block since it has no parent. So, a block
897
    can't be less difficult than the genesis block, therefore each block's
898
    difficulty is set to the maximum value between the calculated
899
    difficulty and the ``GENESIS_DIFFICULTY``.
900
901
    Parameters
902
    ----------
903
    block_number :
904
        Block number of the block.
905
    block_timestamp :
906
        Timestamp of the block.
907
    parent_timestamp :
908
        Timestamp of the parent block.
909
    parent_difficulty :
910
        difficulty of the parent block.
911
    parent_has_ommers:
912
        does the parent have ommers.
913
914
    Returns
915
    -------
916
    difficulty : `ethereum.base_types.Uint`
917
        Computed difficulty for a block.
918
    """
919
    offset = (
920
        int(parent_difficulty)
921
        // 2048
922
        * max(
923
            (2 if parent_has_ommers else 1)
924
            - int(block_timestamp - parent_timestamp) // 9,
925
            -99,
926
        )
927
    )
928
    difficulty = int(parent_difficulty) + offset
929
    # Historical Note: The difficulty bomb was not present in Ethereum at the
930
    # start of Frontier, but was added shortly after launch. However since the
931
    # bomb has no effect prior to block 200000 we pretend it existed from
932
    # genesis.
933
    # See https://github.com/ethereum/go-ethereum/pull/1588
934
    num_bomb_periods = ((int(block_number) - BOMB_DELAY_BLOCKS) // 100000) - 2
935
    if num_bomb_periods >= 0:
936
        difficulty += 2**num_bomb_periods
937
938
    # Some clients raise the difficulty to `MINIMUM_DIFFICULTY` prior to adding
939
    # the bomb. This bug does not matter because the difficulty is always much
940
    # greater than `MINIMUM_DIFFICULTY` on Mainnet.
941
    return Uint(max(difficulty, int(MINIMUM_DIFFICULTY)))