ethereum.forks.gray_glacier.forkethereum.forks.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

63
BASE_FEE_MAX_CHANGE_DENOMINATOR = Uint(8)

ELASTICITY_MULTIPLIER

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ELASTICITY_MULTIPLIER = Uint(2)

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

73
BOMB_DELAY_BLOCKS = 11400000

EMPTY_OMMER_HASH

65
EMPTY_OMMER_HASH = keccak256(rlp.encode([]))

BlockChain

History and current state of the block chain.

68
@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:
80
    """
81
    Transforms the state from the previous hard fork (`old`) into the block
82
    chain object for this hard fork and returns it.
83
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    When forks need to implement an irregular state transition, this function
85
    is used to handle the irregularity. See the :ref:`DAO Fork <dao-fork>` for
86
    an example.
87
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    Parameters
89
    ----------
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    old :
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        Previous block chain object.
92
93
    Returns
94
    -------
95
    new : `BlockChain`
96
        Upgraded block chain object for this hard fork.
97
98
    """
99
    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]:
103
    """
104
    Obtain the list of hashes of the previous 256 blocks in order of
105
    increasing block number.
106
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    This function will return less hashes for the first 256 blocks.
108
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    The ``BLOCKHASH`` opcode needs to access the latest hashes on the chain,
110
    therefore this function retrieves them.
111
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    Parameters
113
    ----------
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    chain :
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        History and current state.
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    Returns
118
    -------
119
    recent_block_hashes : `List[Hash32]`
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        Hashes of the recent 256 blocks in order of increasing block number.
121
122
    """
123
    recent_blocks = chain.blocks[-255:]
124
    # TODO: This function has not been tested rigorously
125
    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
148
    to the chain. Blocks are verified by ensuring that the contents of the
149
    block make logical sense with the contents of the parent block. The
150
    information in the block's header must also match the corresponding
151
    information in the block.
152
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    To implement Ethereum, in theory clients are only required to store the
154
    most recent 255 blocks of the chain since as far as execution is
155
    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
165
    """
166
    validate_header(chain, block.header)
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    validate_ommers(block.ommers, block.header, chain)
167
    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,
178
        time=block.header.timestamp,
187
        difficulty=block.header.difficulty,
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        prev_randao=block.header.prev_randao,
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    )
181
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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,
185
    )
186
    block_state_root = state_root(block_env.state)
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    transactions_root = root(block_output.transactions_trie)
188
    receipt_root = root(block_output.receipts_trie)
189
    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}"
194
        )
195
    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
199
    if receipt_root != block.header.receipt_root:
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        raise InvalidBlock
201
    if block_logs_bloom != block.header.bloom:
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        raise InvalidBlock
203
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    chain.blocks.append(block)
205
    if len(chain.blocks) > 255:
206
        # Real clients have to store more blocks to deal with reorgs, but the
207
        # protocol only requires the last 255
208
        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:
217
    """
218
    Calculates the base fee per gas for the block.
219
220
    Parameters
221
    ----------
222
    block_gas_limit :
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        Gas limit of the block for which the base fee is being calculated.
224
    parent_gas_limit :
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        Gas limit of the parent block.
226
    parent_gas_used :
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        Gas used in the parent block.
228
    parent_base_fee_per_gas :
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        Base fee per gas of the parent block.
230
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    Returns
232
    -------
233
    base_fee_per_gas : `Uint`
234
        Base fee per gas for the block.
235
236
    """
237
    parent_gas_target = parent_gas_limit // ELASTICITY_MULTIPLIER
238
    if not check_gas_limit(block_gas_limit, parent_gas_limit):
239
        raise InvalidBlock
240
241
    if parent_gas_used == parent_gas_target:
242
        expected_base_fee_per_gas = parent_base_fee_per_gas
243
    elif parent_gas_used > parent_gas_target:
244
        gas_used_delta = parent_gas_used - parent_gas_target
245
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        parent_fee_gas_delta = parent_base_fee_per_gas * gas_used_delta
247
        target_fee_gas_delta = parent_fee_gas_delta // parent_gas_target
248
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        base_fee_per_gas_delta = max(
250
            target_fee_gas_delta // BASE_FEE_MAX_CHANGE_DENOMINATOR,
251
            Uint(1),
252
        )
253
254
        expected_base_fee_per_gas = (
255
            parent_base_fee_per_gas + base_fee_per_gas_delta
256
        )
257
    else:
258
        gas_used_delta = parent_gas_target - parent_gas_used
259
260
        parent_fee_gas_delta = parent_base_fee_per_gas * gas_used_delta
261
        target_fee_gas_delta = parent_fee_gas_delta // parent_gas_target
262
263
        base_fee_per_gas_delta = (
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            target_fee_gas_delta // BASE_FEE_MAX_CHANGE_DENOMINATOR
265
        )
266
267
        expected_base_fee_per_gas = (
268
            parent_base_fee_per_gas - base_fee_per_gas_delta
269
        )
270
271
    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:
275
    """
276
    Verifies a block header.
277
278
    In order to consider a block's header valid, the logic for the
279
    quantities in the header should match the logic for the block itself.
280
    For example the header timestamp should be greater than the block's parent
281
    timestamp because the block was created *after* the parent block.
282
    Additionally, the block's number should be directly following the parent
283
    block's number since it is the next block in the sequence.
284
285
    Parameters
286
    ----------
287
    chain :
288
        History and current state.
289
    header :
290
        Header to check for correctness.
291
292
    """
293
    if header.number < Uint(1):
294
        raise InvalidBlock
304
    parent_header_number = header.number - Uint(1)
305
    first_block_number = chain.blocks[0].header.number
306
    last_block_number = chain.blocks[-1].header.number
295
308
    if (
309
        parent_header_number < first_block_number
310
        or parent_header_number > last_block_number
311
    ):
312
        raise InvalidBlock
313
314
    parent_header = chain.blocks[
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        parent_header_number - first_block_number
316
    ].header
296
    parent_header = chain.blocks[-1].header
297
298
    if header.gas_used > header.gas_limit:
299
        raise InvalidBlock
300
301
    expected_base_fee_per_gas = calculate_base_fee_per_gas(
302
        header.gas_limit,
303
        parent_header.gas_limit,
304
        parent_header.gas_used,
305
        parent_header.base_fee_per_gas,
306
    )
307
    if expected_base_fee_per_gas != header.base_fee_per_gas:
308
        raise InvalidBlock
329
330
    parent_has_ommers = parent_header.ommers_hash != EMPTY_OMMER_HASH
309
    if header.timestamp <= parent_header.timestamp:
310
        raise InvalidBlock
311
    if header.number != parent_header.number + Uint(1):
312
        raise InvalidBlock
313
    if len(header.extra_data) > 32:
314
        raise InvalidBlock
337
338
    block_difficulty = calculate_block_difficulty(
339
        header.number,
340
        header.timestamp,
341
        parent_header.timestamp,
342
        parent_header.difficulty,
343
        parent_has_ommers,
344
    )
345
    if header.difficulty != block_difficulty:
315
    if header.difficulty != 0:
316
        raise InvalidBlock
317
    if header.nonce != b"\x00\x00\x00\x00\x00\x00\x00\x00":
318
        raise InvalidBlock
319
    if header.ommers_hash != EMPTY_OMMER_HASH:
320
        raise InvalidBlock
321
322
    block_parent_hash = keccak256(rlp.encode(parent_header))
323
    if header.parent_hash != block_parent_hash:
350
        raise InvalidBlock
351
352
    validate_proof_of_work(header)
324
        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:
356
    """
357
    Generate rlp hash of the header which is to be used for Proof-of-Work
358
    verification.
359
360
    In other words, the PoW artefacts `mix_digest` and `nonce` are ignored
361
    while calculating this hash.
362
363
    A particular PoW is valid for a single hash, that hash is computed by
364
    this function. The `nonce` and `mix_digest` are omitted from this hash
365
    because they are being changed by miners in their search for a sufficient
366
    proof-of-work.
367
368
    Parameters
369
    ----------
370
    header :
371
        The header object for which the hash is to be generated.
372
373
    Returns
374
    -------
375
    hash : `Hash32`
376
        The PoW valid rlp hash of the passed in header.
377
378
    """
379
    header_data_without_pow_artefacts = (
380
        header.parent_hash,
381
        header.ommers_hash,
382
        header.coinbase,
383
        header.state_root,
384
        header.transactions_root,
385
        header.receipt_root,
386
        header.bloom,
387
        header.difficulty,
388
        header.number,
389
        header.gas_limit,
390
        header.gas_used,
391
        header.timestamp,
392
        header.extra_data,
393
        header.base_fee_per_gas,
394
    )
395
396
    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:
400
    """
401
    Validates the Proof of Work constraints.
402
403
    In order to verify that a miner's proof-of-work is valid for a block, a
404
    ``mix-digest`` and ``result`` are calculated using the ``hashimoto_light``
405
    hash function. The mix digest is a hash of the header and the nonce that
406
    is passed through and it confirms whether or not proof-of-work was done
407
    on the correct block. The result is the actual hash value of the block.
408
409
    Parameters
410
    ----------
411
    header :
412
        Header of interest.
413
414
    """
415
    header_hash = generate_header_hash_for_pow(header)
416
    # TODO: Memoize this somewhere and read from that data instead of
417
    # calculating cache for every block validation.
418
    cache = generate_cache(header.number)
419
    mix_digest, result = hashimoto_light(
420
        header_hash, header.nonce, cache, dataset_size(header.number)
421
    )
422
    if mix_digest != header.mix_digest:
423
        raise InvalidBlock
424
425
    limit = Uint(U256.MAX_VALUE) + Uint(1)
426
    if Uint.from_be_bytes(result) > (limit // header.difficulty):
427
        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.forks.gray_glacier.vm.BlockEnvironmentethereum.forks.paris.vm.BlockEnvironment, ​​block_output: ethereum.forks.gray_glacier.vm.BlockOutputethereum.forks.paris.vm.BlockOutput, ​​tx: Transaction) -> Tuple[AddressAddress, Uint]:
332
    """
333
    Check if the transaction is includable in the block.
334
335
    Parameters
336
    ----------
337
    block_env :
338
        The block scoped environment.
339
    block_output :
340
        The block output for the current block.
341
    tx :
342
        The transaction.
343
344
    Returns
345
    -------
346
    sender_address :
347
        The sender of the transaction.
348
    effective_gas_price :
349
        The price to charge for gas when the transaction is executed.
350
351
    Raises
352
    ------
353
    InvalidBlock :
354
        If the transaction is not includable.
355
    GasUsedExceedsLimitError :
356
        If the gas used by the transaction exceeds the block's gas limit.
357
    NonceMismatchError :
358
        If the nonce of the transaction is not equal to the sender's nonce.
359
    InsufficientBalanceError :
360
        If the sender's balance is not enough to pay for the transaction.
361
    InvalidSenderError :
362
        If the transaction is from an address that does not exist anymore.
466
    PriorityFeeGreaterThanMaxFeeError:
363
    PriorityFeeGreaterThanMaxFeeError :
364
        If the priority fee is greater than the maximum fee per gas.
365
    InsufficientMaxFeePerGasError :
366
        If the maximum fee per gas is insufficient for the transaction.
367
368
    """
369
    gas_available = block_env.block_gas_limit - block_output.block_gas_used
370
    if tx.gas > gas_available:
371
        raise GasUsedExceedsLimitError("gas used exceeds limit")
372
    sender_address = recover_sender(block_env.chain_id, tx)
373
    sender_account = get_account(block_env.state, sender_address)
374
375
    if isinstance(tx, FeeMarketTransaction):
376
        if tx.max_fee_per_gas < tx.max_priority_fee_per_gas:
377
            raise PriorityFeeGreaterThanMaxFeeError(
378
                "priority fee greater than max fee"
379
            )
380
        if tx.max_fee_per_gas < block_env.base_fee_per_gas:
381
            raise InsufficientMaxFeePerGasError(
382
                tx.max_fee_per_gas, block_env.base_fee_per_gas
383
            )
384
385
        priority_fee_per_gas = min(
386
            tx.max_priority_fee_per_gas,
387
            tx.max_fee_per_gas - block_env.base_fee_per_gas,
388
        )
389
        effective_gas_price = priority_fee_per_gas + block_env.base_fee_per_gas
390
        max_gas_fee = tx.gas * tx.max_fee_per_gas
391
    else:
392
        if tx.gas_price < block_env.base_fee_per_gas:
393
            raise InvalidBlock
394
        effective_gas_price = tx.gas_price
395
        max_gas_fee = tx.gas * tx.gas_price
396
397
    if sender_account.nonce > Uint(tx.nonce):
398
        raise NonceMismatchError("nonce too low")
399
    elif sender_account.nonce < Uint(tx.nonce):
400
        raise NonceMismatchError("nonce too high")
401
    if Uint(sender_account.balance) < max_gas_fee + Uint(tx.value):
402
        raise InsufficientBalanceError("insufficient sender balance")
403
    if sender_account.code_hash != EMPTY_CODE_HASH:
404
        raise InvalidSenderError("not EOA")
405
406
    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:
415
    """
416
    Make the receipt for a transaction that was executed.
417
418
    Parameters
419
    ----------
420
    tx :
421
        The executed transaction.
422
    error :
423
        Error in the top level frame of the transaction, if any.
424
    cumulative_gas_used :
425
        The total gas used so far in the block after the transaction was
426
        executed.
427
    logs :
428
        The logs produced by the transaction.
429
430
    Returns
431
    -------
432
    receipt :
433
        The receipt for the transaction.
434
435
    """
436
    receipt = Receipt(
437
        succeeded=error is None,
438
        cumulative_gas_used=cumulative_gas_used,
439
        bloom=logs_bloom(logs),
440
        logs=logs,
441
    )
442
443
    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.forks.gray_glacier.vm.BlockEnvironmentethereum.forks.paris.vm.BlockEnvironment, ​​transactions: Tuple[LegacyTransaction | Bytes, ...], ​​ommers: Tuple[Header, ...]) -> ethereum.forks.gray_glacier.vm.BlockOutputethereum.forks.paris.vm.BlockOutput:
450
    """
451
    Executes a block.
452
453
    Many of the contents of a block are stored in data structures called
454
    tries. There is a transactions trie which is similar to a ledger of the
455
    transactions stored in the current block. There is also a receipts trie
456
    which stores the results of executing a transaction, like the post state
457
    and gas used. This function creates and executes the block that is to be
458
    added to the chain.
459
460
    Parameters
461
    ----------
462
    block_env :
463
        The block scoped environment.
464
    transactions :
465
        Transactions included in the block.
570
    ommers :
571
        Headers of ancestor blocks which are not direct parents (formerly
572
        uncles.)
466
467
    Returns
468
    -------
469
    block_output :
470
        The block output for the current block.
471
472
    """
473
    block_output = vm.BlockOutput()
474
475
    for i, tx in enumerate(map(decode_transaction, transactions)):
476
        process_transaction(block_env, block_output, tx, Uint(i))
477
585
    pay_rewards(block_env.state, block_env.number, block_env.coinbase, ommers)
586
478
    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:
593
    """
594
    Validates the ommers mentioned in the block.
595
596
    An ommer block is a block that wasn't canonically added to the
597
    blockchain because it wasn't validated as fast as the canonical block
598
    but was mined at the same time.
599
600
    To be considered valid, the ommers must adhere to the rules defined in
601
    the Ethereum protocol. The maximum amount of ommers is 2 per block and
602
    there cannot be duplicate ommers in a block. Many of the other ommer
603
    constraints are listed in the in-line comments of this function.
604
605
    Parameters
606
    ----------
607
    ommers :
608
        List of ommers mentioned in the current block.
609
    block_header:
610
        The header of current block.
611
    chain :
612
        History and current state.
613
614
    """
615
    block_hash = keccak256(rlp.encode(block_header))
616
    if keccak256(rlp.encode(ommers)) != block_header.ommers_hash:
617
        raise InvalidBlock
618
619
    if len(ommers) == 0:
620
        # Nothing to validate
621
        return
622
623
    # Check that each ommer satisfies the constraints of a header
624
    for ommer in ommers:
625
        if Uint(1) > ommer.number or ommer.number >= block_header.number:
626
            raise InvalidBlock
627
        validate_header(chain, ommer)
628
    if len(ommers) > 2:
629
        raise InvalidBlock
630
631
    ommers_hashes = [keccak256(rlp.encode(ommer)) for ommer in ommers]
632
    if len(ommers_hashes) != len(set(ommers_hashes)):
633
        raise InvalidBlock
634
635
    recent_canonical_blocks = chain.blocks[-(MAX_OMMER_DEPTH + Uint(1)) :]
636
    recent_canonical_block_hashes = {
637
        keccak256(rlp.encode(block.header))
638
        for block in recent_canonical_blocks
639
    }
640
    recent_ommers_hashes: Set[Hash32] = set()
641
    for block in recent_canonical_blocks:
642
        recent_ommers_hashes = recent_ommers_hashes.union(
643
            {keccak256(rlp.encode(ommer)) for ommer in block.ommers}
644
        )
645
646
    for ommer_index, ommer in enumerate(ommers):
647
        ommer_hash = ommers_hashes[ommer_index]
648
        if ommer_hash == block_hash:
649
            raise InvalidBlock
650
        if ommer_hash in recent_canonical_block_hashes:
651
            raise InvalidBlock
652
        if ommer_hash in recent_ommers_hashes:
653
            raise InvalidBlock
654
655
        # Ommer age with respect to the current block. For example, an age of
656
        # 1 indicates that the ommer is a sibling of previous block.
657
        ommer_age = block_header.number - ommer.number
658
        if Uint(1) > ommer_age or ommer_age > MAX_OMMER_DEPTH:
659
            raise InvalidBlock
660
        if ommer.parent_hash not in recent_canonical_block_hashes:
661
            raise InvalidBlock
662
        if ommer.parent_hash == block_header.parent_hash:
663
            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:
672
    """
673
    Pay rewards to the block miner as well as the ommers miners.
674
675
    The miner of the canonical block is rewarded with the predetermined
676
    block reward, ``BLOCK_REWARD``, plus a variable award based off of the
677
    number of ommer blocks that were mined around the same time, and included
678
    in the canonical block's header. An ommer block is a block that wasn't
679
    added to the canonical blockchain because it wasn't validated as fast as
680
    the accepted block but was mined at the same time. Although not all blocks
681
    that are mined are added to the canonical chain, miners are still paid a
682
    reward for their efforts. This reward is called an ommer reward and is
683
    calculated based on the number associated with the ommer block that they
684
    mined.
685
686
    Parameters
687
    ----------
688
    state :
689
        Current account state.
690
    block_number :
691
        Position of the block within the chain.
692
    coinbase :
693
        Address of account which receives block reward and transaction fees.
694
    ommers :
695
        List of ommers mentioned in the current block.
696
697
    """
698
    ommer_count = U256(len(ommers))
699
    miner_reward = BLOCK_REWARD + (ommer_count * (BLOCK_REWARD // U256(32)))
700
    create_ether(state, coinbase, miner_reward)
701
702
    for ommer in ommers:
703
        # Ommer age with respect to the current block.
704
        ommer_age = U256(block_number - ommer.number)
705
        ommer_miner_reward = ((U256(8) - ommer_age) * BLOCK_REWARD) // U256(8)
706
        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.forks.gray_glacier.vm.BlockEnvironmentethereum.forks.paris.vm.BlockEnvironment, ​​block_output: ethereum.forks.gray_glacier.vm.BlockOutputethereum.forks.paris.vm.BlockOutput, ​​tx: Transaction, ​​index: Uint) -> None:
487
    """
488
    Execute a transaction against the provided environment.
489
490
    This function processes the actions needed to execute a transaction.
491
    It decrements the sender's account balance after calculating the gas fee
492
    and refunds them the proper amount after execution. Calling contracts,
493
    deploying code, and incrementing nonces are all examples of actions that
494
    happen within this function or from a call made within this function.
495
496
    Accounts that are marked for deletion are processed and destroyed after
497
    execution.
498
499
    Parameters
500
    ----------
501
    block_env :
502
        Environment for the Ethereum Virtual Machine.
503
    block_output :
504
        The block output for the current block.
505
    tx :
506
        Transaction to execute.
507
    index:
508
        Index of the transaction in the block.
509
510
    """
511
    trie_set(
512
        block_output.transactions_trie,
513
        rlp.encode(index),
514
        encode_transaction(tx),
515
    )
516
517
    intrinsic_gas = validate_transaction(tx)
518
519
    (
520
        sender,
521
        effective_gas_price,
522
    ) = check_transaction(
523
        block_env=block_env,
524
        block_output=block_output,
525
        tx=tx,
526
    )
527
528
    sender_account = get_account(block_env.state, sender)
529
530
    effective_gas_fee = tx.gas * effective_gas_price
531
532
    gas = tx.gas - intrinsic_gas
533
    increment_nonce(block_env.state, sender)
534
535
    sender_balance_after_gas_fee = (
536
        Uint(sender_account.balance) - effective_gas_fee
537
    )
538
    set_account_balance(
539
        block_env.state, sender, U256(sender_balance_after_gas_fee)
540
    )
541
542
    access_list_addresses = set()
543
    access_list_storage_keys = set()
544
    if isinstance(tx, (AccessListTransaction, FeeMarketTransaction)):
545
        for access in tx.access_list:
546
            access_list_addresses.add(access.account)
547
            for slot in access.slots:
548
                access_list_storage_keys.add((access.account, slot))
549
550
    tx_env = vm.TransactionEnvironment(
551
        origin=sender,
552
        gas_price=effective_gas_price,
553
        gas=gas,
554
        access_list_addresses=access_list_addresses,
555
        access_list_storage_keys=access_list_storage_keys,
556
        index_in_block=index,
557
        tx_hash=get_transaction_hash(encode_transaction(tx)),
558
    )
559
560
    message = prepare_message(block_env, tx_env, tx)
561
562
    tx_output = process_message_call(message)
563
564
    tx_gas_used_before_refund = tx.gas - tx_output.gas_left
565
    tx_gas_refund = min(
566
        tx_gas_used_before_refund // Uint(5), Uint(tx_output.refund_counter)
567
    )
568
    tx_gas_used_after_refund = tx_gas_used_before_refund - tx_gas_refund
569
    tx_gas_left = tx.gas - tx_gas_used_after_refund
570
    gas_refund_amount = tx_gas_left * effective_gas_price
571
572
    # For non-1559 transactions effective_gas_price == tx.gas_price
573
    priority_fee_per_gas = effective_gas_price - block_env.base_fee_per_gas
574
    transaction_fee = tx_gas_used_after_refund * priority_fee_per_gas
575
576
    # refund gas
577
    sender_balance_after_refund = get_account(
578
        block_env.state, sender
579
    ).balance + U256(gas_refund_amount)
580
    set_account_balance(block_env.state, sender, sender_balance_after_refund)
581
582
    # transfer miner fees
583
    coinbase_balance_after_mining_fee = get_account(
584
        block_env.state, block_env.coinbase
585
    ).balance + U256(transaction_fee)
814
    if coinbase_balance_after_mining_fee != 0:
815
        set_account_balance(
816
            block_env.state,
817
            block_env.coinbase,
818
            coinbase_balance_after_mining_fee,
819
        )
820
    elif account_exists_and_is_empty(block_env.state, block_env.coinbase):
821
        destroy_account(block_env.state, block_env.coinbase)
586
    set_account_balance(
587
        block_env.state,
588
        block_env.coinbase,
589
        coinbase_balance_after_mining_fee,
590
    )
591
592
    for address in tx_output.accounts_to_delete:
593
        destroy_account(block_env.state, address)
825
826
    destroy_touched_empty_accounts(block_env.state, tx_output.touched_accounts)
594
595
    block_output.block_gas_used += tx_gas_used_after_refund
596
597
    receipt = make_receipt(
598
        tx, tx_output.error, block_output.block_gas_used, tx_output.logs
599
    )
600
601
    receipt_key = rlp.encode(Uint(index))
602
    block_output.receipt_keys += (receipt_key,)
603
604
    trie_set(
605
        block_output.receipts_trie,
606
        receipt_key,
607
        receipt,
608
    )
609
610
    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 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 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:
614
    """
615
    Validates the gas limit for a block.
616
617
    The bounds of the gas limit, ``max_adjustment_delta``, is set as the
618
    quotient of the parent block's gas limit and the
619
    ``LIMIT_ADJUSTMENT_FACTOR``. Therefore, if the gas limit that is
620
    passed through as a parameter is greater than or equal to the *sum* of
621
    the parent's gas and the adjustment delta then the limit for gas is too
622
    high and fails this function's check. Similarly, if the limit is less
623
    than or equal to the *difference* of the parent's gas and the adjustment
624
    delta *or* the predefined ``LIMIT_MINIMUM`` then this function's
625
    check fails because the gas limit doesn't allow for a sufficient or
626
    reasonable amount of gas to be used on a block.
627
628
    Parameters
629
    ----------
630
    gas_limit :
631
        Gas limit to validate.
632
633
    parent_gas_limit :
634
        Gas limit of the parent block.
635
636
    Returns
637
    -------
638
    check : `bool`
639
        True if gas limit constraints are satisfied, False otherwise.
640
641
    """
642
    max_adjustment_delta = parent_gas_limit // GasCosts.LIMIT_ADJUSTMENT_FACTOR
643
    if gas_limit >= parent_gas_limit + max_adjustment_delta:
644
        return False
645
    if gas_limit <= parent_gas_limit - max_adjustment_delta:
646
        return False
647
    if gas_limit < GasCosts.LIMIT_MINIMUM:
648
        return False
649
650
    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 MINIMUM_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:
893
    """
894
    Computes difficulty of a block using its header and parent header.
895
896
    The difficulty is determined by the time the block was created after its
897
    parent. The ``offset`` is calculated using the parent block's difficulty,
898
    ``parent_difficulty``, and the timestamp between blocks. This offset is
899
    then added to the parent difficulty and is stored as the ``difficulty``
900
    variable. If the time between the block and its parent is too short, the
901
    offset will result in a positive number thus making the sum of
902
    ``parent_difficulty`` and ``offset`` to be a greater value in order to
903
    avoid mass forking. But, if the time is long enough, then the offset
904
    results in a negative value making the block less difficult than
905
    its parent.
906
907
    The base standard for a block's difficulty is the predefined value
908
    set for the genesis block since it has no parent. So, a block
909
    can't be less difficult than the genesis block, therefore each block's
910
    difficulty is set to the maximum value between the calculated
911
    difficulty and the ``MINIMUM_DIFFICULTY``.
912
913
    Parameters
914
    ----------
915
    block_number :
916
        Block number of the block.
917
    block_timestamp :
918
        Timestamp of the block.
919
    parent_timestamp :
920
        Timestamp of the parent block.
921
    parent_difficulty :
922
        difficulty of the parent block.
923
    parent_has_ommers:
924
        does the parent have ommers.
925
926
    Returns
927
    -------
928
    difficulty : `ethereum.base_types.Uint`
929
        Computed difficulty for a block.
930
931
    """
932
    offset = (
933
        int(parent_difficulty)
934
        // 2048
935
        * max(
936
            (2 if parent_has_ommers else 1)
937
            - int(block_timestamp - parent_timestamp) // 9,
938
            -99,
939
        )
940
    )
941
    difficulty = int(parent_difficulty) + offset
942
    # Historical Note: The difficulty bomb was not present in Ethereum at the
943
    # start of Frontier, but was added shortly after launch. However since the
944
    # bomb has no effect prior to block 200000 we pretend it existed from
945
    # genesis.
946
    # See https://github.com/ethereum/go-ethereum/pull/1588
947
    num_bomb_periods = ((int(block_number) - BOMB_DELAY_BLOCKS) // 100000) - 2
948
    if num_bomb_periods >= 0:
949
        difficulty += 2**num_bomb_periods
950
951
    # Some clients raise the difficulty to `MINIMUM_DIFFICULTY` prior to adding
952
    # the bomb. This bug does not matter because the difficulty is always much
953
    # greater than `MINIMUM_DIFFICULTY` on Mainnet.
954
    return Uint(max(difficulty, int(MINIMUM_DIFFICULTY)))