ethereum.forks.cancun.forkethereum.forks.prague.fork

Ethereum Specification.

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

Introduction

Entry point for the Ethereum specification.

BASE_FEE_MAX_CHANGE_DENOMINATOR

99
BASE_FEE_MAX_CHANGE_DENOMINATOR = Uint(8)

ELASTICITY_MULTIPLIER

100
ELASTICITY_MULTIPLIER = Uint(2)

EMPTY_OMMER_HASH

101
EMPTY_OMMER_HASH = keccak256(rlp.encode([]))

SYSTEM_ADDRESS

102
SYSTEM_ADDRESS = hex_to_address("0xfffffffffffffffffffffffffffffffffffffffe")

BEACON_ROOTS_ADDRESS

103
BEACON_ROOTS_ADDRESS = hex_to_address(
104
    "0x000F3df6D732807Ef1319fB7B8bB8522d0Beac02"
105
)

SYSTEM_TRANSACTION_GAS

106
SYSTEM_TRANSACTION_GAS = Uint(30000000)

MAX_BLOB_GAS_PER_BLOCK

98
MAX_BLOB_GAS_PER_BLOCK: Final[U64] = U64(786432)
107
MAX_BLOB_GAS_PER_BLOCK: Final[U64] = U64(1179648)

VERSIONED_HASH_VERSION_KZG

108
VERSIONED_HASH_VERSION_KZG = b"\x01"

WITHDRAWAL_REQUEST_PREDEPLOY_ADDRESS

110
WITHDRAWAL_REQUEST_PREDEPLOY_ADDRESS = hex_to_address(
111
    "0x00000961Ef480Eb55e80D19ad83579A64c007002"
112
)

CONSOLIDATION_REQUEST_PREDEPLOY_ADDRESS

113
CONSOLIDATION_REQUEST_PREDEPLOY_ADDRESS = hex_to_address(
114
    "0x0000BBdDc7CE488642fb579F8B00f3a590007251"
115
)

HISTORY_STORAGE_ADDRESS

116
HISTORY_STORAGE_ADDRESS = hex_to_address(
117
    "0x0000F90827F1C53a10cb7A02335B175320002935"
118
)

BlockChain

History and current state of the block chain.

121
@final
122
@dataclass
class BlockChain:

blocks

128
    blocks: List[Block]

state

129
    state: State

chain_id

130
    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:
134
    <snip>
153
    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]:
157
    <snip>
177
    recent_blocks = chain.blocks[-255:]
178
    # TODO: This function has not been tested rigorously
179
    if len(recent_blocks) == 0:
180
        return []
181
182
    recent_block_hashes = []
183
184
    for block in recent_blocks:
185
        prev_block_hash = block.header.parent_hash
186
        recent_block_hashes.append(prev_block_hash)
187
188
    # We are computing the hash only for the most recent block and not for
189
    # the rest of the blocks as they have successors which have the hash of
190
    # the current block as parent hash.
191
    most_recent_block_hash = keccak256(rlp.encode(recent_blocks[-1].header))
192
    recent_block_hashes.append(most_recent_block_hash)
193
194
    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:
198
    <snip>
220
    validate_header(chain, block.header)
221
    if block.ommers != ():
222
        raise InvalidBlock
223
224
    block_state = BlockState(pre_state=chain.state)
225
226
    block_env = vm.BlockEnvironment(
227
        chain_id=chain.chain_id,
228
        state=block_state,
229
        block_gas_limit=block.header.gas_limit,
230
        block_hashes=get_last_256_block_hashes(chain),
231
        coinbase=block.header.coinbase,
232
        number=block.header.number,
233
        base_fee_per_gas=block.header.base_fee_per_gas,
234
        time=block.header.timestamp,
235
        prev_randao=block.header.prev_randao,
236
        excess_blob_gas=block.header.excess_blob_gas,
237
        parent_beacon_block_root=block.header.parent_beacon_block_root,
238
    )
239
240
    block_output = apply_body(
241
        block_env=block_env,
242
        transactions=block.transactions,
243
        withdrawals=block.withdrawals,
244
    )
245
    block_diff = extract_block_diff(block_state)
246
    block_state_root, _ = chain.state.compute_state_root_and_trie_changes(
247
        block_diff.account_changes, block_diff.storage_changes
248
    )
249
    transactions_root = root(block_output.transactions_trie)
250
    receipt_root = root(block_output.receipts_trie)
251
    block_logs_bloom = logs_bloom(block_output.block_logs)
252
    withdrawals_root = root(block_output.withdrawals_trie)
253
    requests_hash = compute_requests_hash(block_output.requests)
254
255
    if block_output.block_gas_used != block.header.gas_used:
256
        raise InvalidBlock(
257
            f"{block_output.block_gas_used} != {block.header.gas_used}"
258
        )
259
    if transactions_root != block.header.transactions_root:
260
        raise InvalidBlock
261
    if block_state_root != block.header.state_root:
262
        raise InvalidBlock
263
    if receipt_root != block.header.receipt_root:
264
        raise InvalidBlock
265
    if block_logs_bloom != block.header.bloom:
266
        raise InvalidBlock
267
    if withdrawals_root != block.header.withdrawals_root:
268
        raise InvalidBlock
269
    if block_output.blob_gas_used != block.header.blob_gas_used:
270
        raise InvalidBlock
271
    if requests_hash != block.header.requests_hash:
272
        raise InvalidBlock
273
274
    apply_changes_to_state(chain.state, block_diff)
275
    chain.blocks.append(block)
276
    if len(chain.blocks) > 255:
277
        # Real clients have to store more blocks to deal with reorgs, but the
278
        # protocol only requires the last 255
279
        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:
288
    <snip>
308
    parent_gas_target = parent_gas_limit // ELASTICITY_MULTIPLIER
309
    if not check_gas_limit(block_gas_limit, parent_gas_limit):
310
        raise InvalidBlock
311
312
    if parent_gas_used == parent_gas_target:
313
        expected_base_fee_per_gas = parent_base_fee_per_gas
314
    elif parent_gas_used > parent_gas_target:
315
        gas_used_delta = parent_gas_used - parent_gas_target
316
317
        parent_fee_gas_delta = parent_base_fee_per_gas * gas_used_delta
318
        target_fee_gas_delta = parent_fee_gas_delta // parent_gas_target
319
320
        base_fee_per_gas_delta = max(
321
            target_fee_gas_delta // BASE_FEE_MAX_CHANGE_DENOMINATOR,
322
            Uint(1),
323
        )
324
325
        expected_base_fee_per_gas = (
326
            parent_base_fee_per_gas + base_fee_per_gas_delta
327
        )
328
    else:
329
        gas_used_delta = parent_gas_target - parent_gas_used
330
331
        parent_fee_gas_delta = parent_base_fee_per_gas * gas_used_delta
332
        target_fee_gas_delta = parent_fee_gas_delta // parent_gas_target
333
334
        base_fee_per_gas_delta = (
335
            target_fee_gas_delta // BASE_FEE_MAX_CHANGE_DENOMINATOR
336
        )
337
338
        expected_base_fee_per_gas = (
339
            parent_base_fee_per_gas - base_fee_per_gas_delta
340
        )
341
342
    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:
346
    <snip>
364
    if header.number < Uint(1):
365
        raise InvalidBlock
366
367
    parent_header = chain.blocks[-1].header
368
369
    excess_blob_gas = calculate_excess_blob_gas(parent_header)
370
    if header.excess_blob_gas != excess_blob_gas:
371
        raise InvalidBlock
372
373
    if header.gas_used > header.gas_limit:
374
        raise InvalidBlock
375
376
    expected_base_fee_per_gas = calculate_base_fee_per_gas(
377
        header.gas_limit,
378
        parent_header.gas_limit,
379
        parent_header.gas_used,
380
        parent_header.base_fee_per_gas,
381
    )
382
    if expected_base_fee_per_gas != header.base_fee_per_gas:
383
        raise InvalidBlock
384
    if header.timestamp <= parent_header.timestamp:
385
        raise InvalidBlock
386
    if header.number != parent_header.number + Uint(1):
387
        raise InvalidBlock
388
    if len(header.extra_data) > 32:
389
        raise InvalidBlock
390
    if header.difficulty != 0:
391
        raise InvalidBlock
392
    if header.nonce != b"\x00\x00\x00\x00\x00\x00\x00\x00":
393
        raise InvalidBlock
394
    if header.ommers_hash != EMPTY_OMMER_HASH:
395
        raise InvalidBlock
396
397
    block_parent_hash = keccak256(rlp.encode(parent_header))
398
    if header.parent_hash != block_parent_hash:
399
        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. tx_state : The transaction state tracker.

Returns

sender_address : The sender of the transaction. effective_gas_price : The price to charge for gas when the transaction is executed. blob_versioned_hashes : The blob versioned hashes of the transaction. tx_blob_gas_used: The blob gas used by the transaction.

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 : If the priority fee is greater than the maximum fee per gas. InsufficientMaxFeePerGasError : If the maximum fee per gas is insufficient for the transaction. InsufficientMaxFeePerBlobGasError : If the maximum fee per blob gas is insufficient for the transaction. BlobGasLimitExceededError : If the blob gas used by the transaction exceeds the block's blob gas limit. InvalidBlobVersionedHashError : If the transaction contains a blob versioned hash with an invalid version. NoBlobDataError : If the transaction is a type 3 but has no blobs. TransactionTypeContractCreationError: If the transaction type is not allowed to create contracts. EmptyAuthorizationListError : If the transaction is a SetCodeTransaction and the authorization list is empty.

def check_transaction(block_env: ethereum.forks.cancun.vm.BlockEnvironmentethereum.forks.prague.vm.BlockEnvironment, ​​block_output: ethereum.forks.cancun.vm.BlockOutputethereum.forks.prague.vm.BlockOutput, ​​tx: Transaction, ​​tx_state: TransactionState) -> Tuple[Address, Uint, Tuple[VersionedHash, ...], U64]:
408
    <snip>
466
    gas_available = block_env.block_gas_limit - block_output.block_gas_used
467
    blob_gas_available = MAX_BLOB_GAS_PER_BLOCK - block_output.blob_gas_used
468
469
    if tx.gas > gas_available:
470
        raise GasUsedExceedsLimitError("gas used exceeds limit")
471
472
    tx_blob_gas_used = calculate_total_blob_gas(tx)
473
    if tx_blob_gas_used > blob_gas_available:
474
        raise BlobGasLimitExceededError("blob gas limit exceeded")
475
476
    tx_chain_id = chain_id(tx)
477
    if tx_chain_id is not None and tx_chain_id != block_env.chain_id:
478
        raise WrongChainIdError(
479
            expected=block_env.chain_id,
480
            actual=tx_chain_id,
481
        )
482
483
    sender_address = recover_sender(tx)
484
    sender_account = get_account(tx_state, sender_address)
485
486
    if isinstance(tx, FeeMarketCapableTransaction):
487
        if tx.max_fee_per_gas < tx.max_priority_fee_per_gas:
488
            raise PriorityFeeGreaterThanMaxFeeError(
489
                "priority fee greater than max fee"
490
            )
491
        if tx.max_fee_per_gas < block_env.base_fee_per_gas:
492
            raise InsufficientMaxFeePerGasError(
493
                tx.max_fee_per_gas, block_env.base_fee_per_gas
494
            )
495
496
        priority_fee_per_gas = min(
497
            tx.max_priority_fee_per_gas,
498
            tx.max_fee_per_gas - block_env.base_fee_per_gas,
499
        )
500
        effective_gas_price = priority_fee_per_gas + block_env.base_fee_per_gas
501
        max_gas_fee = tx.gas * tx.max_fee_per_gas
502
    else:
503
        if tx.gas_price < block_env.base_fee_per_gas:
504
            raise InvalidBlock
505
        effective_gas_price = tx.gas_price
506
        max_gas_fee = tx.gas * tx.gas_price
507
508
    if isinstance(tx, BlobTransaction):
484
        if not isinstance(tx.to, Address):
485
            raise TransactionTypeContractCreationError(tx)
486
        if len(tx.blob_versioned_hashes) == 0:
509
        if len(tx.blob_versioned_hashes) == 0:
510
            raise NoBlobDataError("no blob data in transaction")
511
        for blob_versioned_hash in tx.blob_versioned_hashes:
512
            if blob_versioned_hash[0:1] != VERSIONED_HASH_VERSION_KZG:
513
                raise InvalidBlobVersionedHashError(
514
                    "invalid blob versioned hash"
515
                )
516
517
        blob_gas_price = calculate_blob_gas_price(block_env.excess_blob_gas)
518
        if Uint(tx.max_fee_per_blob_gas) < blob_gas_price:
519
            raise InsufficientMaxFeePerBlobGasError(
520
                "insufficient max fee per blob gas"
521
            )
522
523
        max_gas_fee += Uint(calculate_total_blob_gas(tx)) * Uint(
524
            tx.max_fee_per_blob_gas
525
        )
526
        blob_versioned_hashes = tx.blob_versioned_hashes
527
    else:
528
        blob_versioned_hashes = ()
529
530
    if isinstance(tx, (BlobTransaction, SetCodeTransaction)):
531
        if not isinstance(tx.to, Address):
532
            raise TransactionTypeContractCreationError(tx)
533
534
    if isinstance(tx, SetCodeTransaction):
535
        if not any(tx.authorizations):
536
            raise EmptyAuthorizationListError("empty authorization list")
537
538
    if sender_account.nonce > Uint(tx.nonce):
539
        raise NonceMismatchError("nonce too low")
540
    elif sender_account.nonce < Uint(tx.nonce):
541
        raise NonceMismatchError("nonce too high")
542
543
    if Uint(sender_account.balance) < max_gas_fee + Uint(tx.value):
544
        raise InsufficientBalanceError("insufficient sender balance")
512
    if sender_account.code_hash != EMPTY_CODE_HASH:
545
    sender_code = get_code(tx_state, sender_account.code_hash)
546
    if sender_account.code_hash != EMPTY_CODE_HASH and not is_valid_delegation(
547
        sender_code
548
    ):
549
        raise InvalidSenderError("not EOA")
550
551
    return (
552
        sender_address,
553
        effective_gas_price,
554
        blob_versioned_hashes,
555
        tx_blob_gas_used,
556
    )

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:
565
    <snip>
586
    receipt = Receipt(
587
        succeeded=error is None,
588
        cumulative_gas_used=cumulative_gas_used,
589
        bloom=logs_bloom(logs),
590
        logs=logs,
591
    )
592
593
    return encode_receipt(tx, receipt)

process_checked_system_transaction

Process a system transaction and raise an error if the contract does not contain code or if the transaction fails.

Parameters

block_env : The block scoped environment. target_address : Address of the contract to call. data : Data to pass to the contract.

Returns

system_tx_output : MessageCallOutput Output of processing the system transaction.

def process_checked_system_transaction(block_env: ethereum.forks.prague.vm.BlockEnvironment, ​​target_address: Address, ​​data: Bytes) -> MessageCallOutput:
601
    <snip>
620
    # Pre-check that the system contract has code. We use a throwaway
621
    # TransactionState here that is *never* propagated back to BlockState
622
    # (no incorporate_tx_into_block call); the same get_account / get_code
623
    # lookups are performed and properly tracked by
624
    # process_unchecked_system_transaction below, which this function
625
    # always calls. Reading via a TransactionState (rather than directly
626
    # against pre_state) lets us see system contracts deployed earlier in
627
    # the same block — see EIP-7002 and EIP-7251 for this edge case.
628
    untracked_state = TransactionState(parent=block_env.state)
629
    system_contract_code = get_code(
630
        untracked_state,
631
        get_account(untracked_state, target_address).code_hash,
632
    )
633
634
    if len(system_contract_code) == 0:
635
        raise InvalidBlock(
636
            f"System contract address {target_address.hex()} does not "
637
            "contain code"
638
        )
639
640
    system_tx_output = process_unchecked_system_transaction(
641
        block_env,
642
        target_address,
643
        data,
644
    )
645
646
    if system_tx_output.error:
647
        raise InvalidBlock(
648
            f"System contract ({target_address.hex()}) call failed: "
649
            f"{system_tx_output.error}"
650
        )
651
652
    return system_tx_output

process_unchecked_system_transaction

Process a system transaction without checking if the contract contains code or if the transaction fails.

Parameters

block_env : The block scoped environment. target_address : Address of the contract to call. data : Data to pass to the contract.

Returns

system_tx_output : MessageCallOutput Output of processing the system transaction.

def process_unchecked_system_transaction(block_env: ethereum.forks.cancun.vm.BlockEnvironmentethereum.forks.prague.vm.BlockEnvironment, ​​target_address: Address, ​​data: Bytes) -> MessageCallOutput:
660
    <snip>
679
    system_tx_state = TransactionState(parent=block_env.state)
680
    system_contract_code = get_code(
681
        system_tx_state,
682
        get_account(system_tx_state, target_address).code_hash,
683
    )
684
685
    tx_env = vm.TransactionEnvironment(
686
        origin=SYSTEM_ADDRESS,
687
        gas_price=block_env.base_fee_per_gas,
688
        gas=SYSTEM_TRANSACTION_GAS,
689
        access_list_addresses=set(),
690
        access_list_storage_keys=set(),
691
        state=system_tx_state,
692
        blob_versioned_hashes=(),
693
        authorizations=(),
694
        index_in_block=None,
695
        tx_hash=None,
696
    )
697
698
    system_tx_message = Message(
699
        block_env=block_env,
700
        tx_env=tx_env,
701
        caller=SYSTEM_ADDRESS,
702
        target=target_address,
703
        gas=SYSTEM_TRANSACTION_GAS,
704
        value=U256(0),
705
        data=data,
706
        code=system_contract_code,
707
        depth=Uint(0),
708
        current_target=target_address,
709
        code_address=target_address,
710
        should_transfer_value=False,
711
        is_static=False,
712
        accessed_addresses=set(),
713
        accessed_storage_keys=set(),
714
        disable_precompiles=False,
715
        parent_evm=None,
716
    )
717
718
    system_tx_output = process_message_call(system_tx_message)
719
720
    incorporate_tx_into_block(system_tx_state)
721
722
    return system_tx_output

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. withdrawals : Withdrawals to be processed in the current block.

Returns

block_output : The block output for the current block.

def apply_body(block_env: ethereum.forks.cancun.vm.BlockEnvironmentethereum.forks.prague.vm.BlockEnvironment, ​​transactions: Tuple[LegacyTransaction | Bytes, ...], ​​withdrawals: Tuple[Withdrawal, ...]) -> ethereum.forks.cancun.vm.BlockOutputethereum.forks.prague.vm.BlockOutput:
730
    <snip>
755
    block_output = vm.BlockOutput()
756
757
    process_unchecked_system_transaction(
758
        block_env=block_env,
759
        target_address=BEACON_ROOTS_ADDRESS,
760
        data=block_env.parent_beacon_block_root,
761
    )
762
763
    process_unchecked_system_transaction(
764
        block_env=block_env,
765
        target_address=HISTORY_STORAGE_ADDRESS,
766
        data=block_env.block_hashes[-1],  # The parent hash
767
    )
768
769
    for i, tx in enumerate(map(decode_transaction, transactions)):
770
        process_transaction(block_env, block_output, tx, Uint(i))
771
772
    process_withdrawals(block_env, block_output, withdrawals)
773
774
    process_general_purpose_requests(
775
        block_env=block_env,
776
        block_output=block_output,
777
    )
778
779
    return block_output

process_general_purpose_requests

Process all the requests in the block.

Parameters

block_env : The execution environment for the Block. block_output : The block output for the current block.

def process_general_purpose_requests(block_env: ethereum.forks.prague.vm.BlockEnvironment, ​​block_output: ethereum.forks.prague.vm.BlockOutput) -> None:
786
    <snip>
797
    # Requests are to be in ascending order of request type
798
    deposit_requests = parse_deposit_requests(block_output)
799
    requests_from_execution = block_output.requests
800
    if len(deposit_requests) > 0:
801
        requests_from_execution.append(DEPOSIT_REQUEST_TYPE + deposit_requests)
802
803
    system_withdrawal_tx_output = process_checked_system_transaction(
804
        block_env=block_env,
805
        target_address=WITHDRAWAL_REQUEST_PREDEPLOY_ADDRESS,
806
        data=b"",
807
    )
808
809
    if len(system_withdrawal_tx_output.return_data) > 0:
810
        requests_from_execution.append(
811
            WITHDRAWAL_REQUEST_TYPE + system_withdrawal_tx_output.return_data
812
        )
813
814
    system_consolidation_tx_output = process_checked_system_transaction(
815
        block_env=block_env,
816
        target_address=CONSOLIDATION_REQUEST_PREDEPLOY_ADDRESS,
817
        data=b"",
818
    )
819
820
    if len(system_consolidation_tx_output.return_data) > 0:
821
        requests_from_execution.append(
822
            CONSOLIDATION_REQUEST_TYPE
823
            + system_consolidation_tx_output.return_data
824
        )

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.cancun.vm.BlockEnvironmentethereum.forks.prague.vm.BlockEnvironment, ​​block_output: ethereum.forks.cancun.vm.BlockOutputethereum.forks.prague.vm.BlockOutput, ​​tx: Transaction, ​​index: Uint) -> None:
833
    <snip>
857
    tx_state = TransactionState(parent=block_env.state)
858
859
    trie_set(
860
        block_output.transactions_trie,
861
        rlp.encode(index),
862
        encode_transaction(tx),
863
    )
864
712
    intrinsic_gas = validate_transaction(tx)
865
    intrinsic = validate_transaction(tx)
866
867
    (
868
        sender,
869
        effective_gas_price,
870
        blob_versioned_hashes,
871
        tx_blob_gas_used,
872
    ) = check_transaction(
873
        block_env=block_env,
874
        block_output=block_output,
875
        tx=tx,
876
        tx_state=tx_state,
877
    )
878
879
    sender_account = get_account(tx_state, sender)
880
881
    if isinstance(tx, BlobTransaction):
882
        blob_gas_fee = calculate_data_fee(block_env.excess_blob_gas, tx)
883
    else:
884
        blob_gas_fee = Uint(0)
885
886
    effective_gas_fee = tx.gas * effective_gas_price
887
735
    gas = tx.gas - intrinsic_gas
888
    gas = tx.gas - intrinsic.regular
889
    increment_nonce(tx_state, sender)
890
891
    sender_balance_after_gas_fee = (
892
        Uint(sender_account.balance) - effective_gas_fee - blob_gas_fee
893
    )
894
    set_account_balance(tx_state, sender, U256(sender_balance_after_gas_fee))
895
896
    access_list_addresses = set()
897
    access_list_storage_keys = set()
898
    access_list_addresses.add(block_env.coinbase)
746
    if isinstance(
747
        tx, (AccessListTransaction, FeeMarketTransaction, BlobTransaction)
748
    ):
899
    if has_access_list(tx):
900
        for access in tx.access_list:
901
            access_list_addresses.add(access.account)
902
            for slot in access.slots:
903
                access_list_storage_keys.add((access.account, slot))
904
905
    authorizations: Tuple[Authorization, ...] = ()
906
    if isinstance(tx, SetCodeTransaction):
907
        authorizations = tx.authorizations
908
909
    tx_env = vm.TransactionEnvironment(
910
        origin=sender,
911
        gas_price=effective_gas_price,
912
        gas=gas,
913
        access_list_addresses=access_list_addresses,
914
        access_list_storage_keys=access_list_storage_keys,
915
        state=tx_state,
916
        blob_versioned_hashes=blob_versioned_hashes,
917
        authorizations=authorizations,
918
        index_in_block=index,
919
        tx_hash=get_transaction_hash(encode_transaction(tx)),
920
    )
921
922
    message = prepare_message(block_env, tx_env, tx)
923
924
    tx_output = process_message_call(message)
925
770
    tx_gas_used_before_refund = tx.gas - tx_output.gas_left
926
    # For EIP-7623 we first calculate the execution_gas_used, which includes
927
    # the execution gas refund.
928
    tx_gas_used_before_refund = tx.gas - tx_output.gas_left
929
    tx_gas_refund = min(
930
        tx_gas_used_before_refund // Uint(5), Uint(tx_output.refund_counter)
931
    )
932
    tx_gas_used_after_refund = tx_gas_used_before_refund - tx_gas_refund
933
934
    # Transactions with less execution_gas_used than the floor pay at the
935
    # floor cost.
936
    tx_gas_used_after_refund = max(
937
        tx_gas_used_after_refund, intrinsic.calldata_floor
938
    )
939
940
    tx_gas_left = tx.gas - tx_gas_used_after_refund
941
    gas_refund_amount = tx_gas_left * effective_gas_price
942
943
    # For non-1559 transactions effective_gas_price == tx.gas_price
944
    priority_fee_per_gas = effective_gas_price - block_env.base_fee_per_gas
945
    transaction_fee = tx_gas_used_after_refund * priority_fee_per_gas
946
947
    # refund gas
948
    create_ether(tx_state, sender, U256(gas_refund_amount))
949
950
    # transfer miner fees
951
    create_ether(tx_state, block_env.coinbase, U256(transaction_fee))
952
953
    for address in tx_output.accounts_to_delete:
954
        destroy_account(tx_state, address)
955
956
    block_output.block_gas_used += tx_gas_used_after_refund
957
    block_output.blob_gas_used += tx_blob_gas_used
958
959
    receipt = make_receipt(
960
        tx, tx_output.error, block_output.block_gas_used, tx_output.logs
961
    )
962
963
    receipt_key = rlp.encode(Uint(index))
964
    block_output.receipt_keys += (receipt_key,)
965
966
    trie_set(
967
        block_output.receipts_trie,
968
        receipt_key,
969
        receipt,
970
    )
971
972
    block_output.block_logs += tx_output.logs
973
974
    incorporate_tx_into_block(tx_state)

process_withdrawals

Increase the balance of the withdrawing account.

def process_withdrawals(block_env: ethereum.forks.cancun.vm.BlockEnvironmentethereum.forks.prague.vm.BlockEnvironment, ​​block_output: ethereum.forks.cancun.vm.BlockOutputethereum.forks.prague.vm.BlockOutput, ​​withdrawals: Tuple[Withdrawal, ...]) -> None:
982
    <snip>
985
    wd_state = TransactionState(parent=block_env.state)
986
987
    for i, wd in enumerate(withdrawals):
988
        trie_set(
989
            block_output.withdrawals_trie,
990
            rlp.encode(Uint(i)),
991
            rlp.encode(wd),
992
        )
993
994
        create_ether(wd_state, wd.address, wd.amount * U256(10**9))
995
996
    incorporate_tx_into_block(wd_state)

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. Therefore, if the gas limit that is passed passed through as a parameter is greater than or equal to the through as a parameter is greater than or equal to the sum of of the the parent's gas and the adjustment delta then the limit for gas is tooparent's gas and the adjustment delta then the limit for gas is too high high and fails this function's check. Similarly, if the limit is lessand fails this function's check. Similarly, if the limit is less than or than or equal to the equal to the difference of the parent's gas and the adjustment of the parent's gas and the adjustment delta or delta or the predefined the predefined LIMIT_MINIMUM then this function's then this function's check fails because check fails because the gas limit doesn't allow for a sufficient orthe gas limit doesn't allow for a sufficient or reasonable amount of gas to reasonable amount of gas to be used on a block.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:
1000
    <snip>
1028
    max_adjustment_delta = parent_gas_limit // GasCosts.LIMIT_ADJUSTMENT_FACTOR
1029
    if gas_limit >= parent_gas_limit + max_adjustment_delta:
1030
        return False
1031
    if gas_limit <= parent_gas_limit - max_adjustment_delta:
1032
        return False
1033
    if gas_limit < GasCosts.LIMIT_MINIMUM:
1034
        return False
1035
1036
    return True