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

97
BASE_FEE_MAX_CHANGE_DENOMINATOR = Uint(8)

ELASTICITY_MULTIPLIER

98
ELASTICITY_MULTIPLIER = Uint(2)

EMPTY_OMMER_HASH

99
EMPTY_OMMER_HASH = keccak256(rlp.encode([]))

SYSTEM_ADDRESS

100
SYSTEM_ADDRESS = hex_to_address("0xfffffffffffffffffffffffffffffffffffffffe")

BEACON_ROOTS_ADDRESS

101
BEACON_ROOTS_ADDRESS = hex_to_address(
102
    "0x000F3df6D732807Ef1319fB7B8bB8522d0Beac02"
103
)

SYSTEM_TRANSACTION_GAS

104
SYSTEM_TRANSACTION_GAS = Uint(30000000)

MAX_BLOB_GAS_PER_BLOCK

95
MAX_BLOB_GAS_PER_BLOCK: Final[U64] = U64(786432)
105
MAX_BLOB_GAS_PER_BLOCK: Final[U64] = U64(1179648)

VERSIONED_HASH_VERSION_KZG

106
VERSIONED_HASH_VERSION_KZG = b"\x01"

WITHDRAWAL_REQUEST_PREDEPLOY_ADDRESS

108
WITHDRAWAL_REQUEST_PREDEPLOY_ADDRESS = hex_to_address(
109
    "0x00000961Ef480Eb55e80D19ad83579A64c007002"
110
)

CONSOLIDATION_REQUEST_PREDEPLOY_ADDRESS

111
CONSOLIDATION_REQUEST_PREDEPLOY_ADDRESS = hex_to_address(
112
    "0x0000BBdDc7CE488642fb579F8B00f3a590007251"
113
)

HISTORY_STORAGE_ADDRESS

114
HISTORY_STORAGE_ADDRESS = hex_to_address(
115
    "0x0000F90827F1C53a10cb7A02335B175320002935"
116
)

BlockChain

History and current state of the block chain.

119
@final
120
@dataclass
class BlockChain:

blocks

126
    blocks: List[Block]

state

127
    state: State

chain_id

128
    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:
132
    <snip>
151
    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]:
155
    <snip>
175
    recent_blocks = chain.blocks[-255:]
176
    # TODO: This function has not been tested rigorously
177
    if len(recent_blocks) == 0:
178
        return []
179
180
    recent_block_hashes = []
181
182
    for block in recent_blocks:
183
        prev_block_hash = block.header.parent_hash
184
        recent_block_hashes.append(prev_block_hash)
185
186
    # We are computing the hash only for the most recent block and not for
187
    # the rest of the blocks as they have successors which have the hash of
188
    # the current block as parent hash.
189
    most_recent_block_hash = keccak256(rlp.encode(recent_blocks[-1].header))
190
    recent_block_hashes.append(most_recent_block_hash)
191
192
    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:
196
    <snip>
218
    validate_header(chain, block.header)
219
    if block.ommers != ():
220
        raise InvalidBlock
221
222
    block_state = BlockState(pre_state=chain.state)
223
224
    block_env = vm.BlockEnvironment(
225
        chain_id=chain.chain_id,
226
        state=block_state,
227
        block_gas_limit=block.header.gas_limit,
228
        block_hashes=get_last_256_block_hashes(chain),
229
        coinbase=block.header.coinbase,
230
        number=block.header.number,
231
        base_fee_per_gas=block.header.base_fee_per_gas,
232
        time=block.header.timestamp,
233
        prev_randao=block.header.prev_randao,
234
        excess_blob_gas=block.header.excess_blob_gas,
235
        parent_beacon_block_root=block.header.parent_beacon_block_root,
236
    )
237
238
    block_output = apply_body(
239
        block_env=block_env,
240
        transactions=block.transactions,
241
        withdrawals=block.withdrawals,
242
    )
243
    block_diff = extract_block_diff(block_state)
244
    block_state_root, _ = chain.state.compute_state_root_and_trie_changes(
245
        block_diff.account_changes, block_diff.storage_changes
246
    )
247
    transactions_root = root(block_output.transactions_trie)
248
    receipt_root = root(block_output.receipts_trie)
249
    block_logs_bloom = logs_bloom(block_output.block_logs)
250
    withdrawals_root = root(block_output.withdrawals_trie)
251
    requests_hash = compute_requests_hash(block_output.requests)
252
253
    if block_output.block_gas_used != block.header.gas_used:
254
        raise InvalidBlock(
255
            f"{block_output.block_gas_used} != {block.header.gas_used}"
256
        )
257
    if transactions_root != block.header.transactions_root:
258
        raise InvalidBlock
259
    if block_state_root != block.header.state_root:
260
        raise InvalidBlock
261
    if receipt_root != block.header.receipt_root:
262
        raise InvalidBlock
263
    if block_logs_bloom != block.header.bloom:
264
        raise InvalidBlock
265
    if withdrawals_root != block.header.withdrawals_root:
266
        raise InvalidBlock
267
    if block_output.blob_gas_used != block.header.blob_gas_used:
268
        raise InvalidBlock
269
    if requests_hash != block.header.requests_hash:
270
        raise InvalidBlock
271
272
    apply_changes_to_state(chain.state, block_diff)
273
    chain.blocks.append(block)
274
    if len(chain.blocks) > 255:
275
        # Real clients have to store more blocks to deal with reorgs, but the
276
        # protocol only requires the last 255
277
        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:
286
    <snip>
306
    parent_gas_target = parent_gas_limit // ELASTICITY_MULTIPLIER
307
    if not check_gas_limit(block_gas_limit, parent_gas_limit):
308
        raise InvalidBlock
309
310
    if parent_gas_used == parent_gas_target:
311
        expected_base_fee_per_gas = parent_base_fee_per_gas
312
    elif parent_gas_used > parent_gas_target:
313
        gas_used_delta = parent_gas_used - parent_gas_target
314
315
        parent_fee_gas_delta = parent_base_fee_per_gas * gas_used_delta
316
        target_fee_gas_delta = parent_fee_gas_delta // parent_gas_target
317
318
        base_fee_per_gas_delta = max(
319
            target_fee_gas_delta // BASE_FEE_MAX_CHANGE_DENOMINATOR,
320
            Uint(1),
321
        )
322
323
        expected_base_fee_per_gas = (
324
            parent_base_fee_per_gas + base_fee_per_gas_delta
325
        )
326
    else:
327
        gas_used_delta = parent_gas_target - parent_gas_used
328
329
        parent_fee_gas_delta = parent_base_fee_per_gas * gas_used_delta
330
        target_fee_gas_delta = parent_fee_gas_delta // parent_gas_target
331
332
        base_fee_per_gas_delta = (
333
            target_fee_gas_delta // BASE_FEE_MAX_CHANGE_DENOMINATOR
334
        )
335
336
        expected_base_fee_per_gas = (
337
            parent_base_fee_per_gas - base_fee_per_gas_delta
338
        )
339
340
    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:
344
    <snip>
362
    if header.number < Uint(1):
363
        raise InvalidBlock
364
365
    parent_header = chain.blocks[-1].header
366
367
    excess_blob_gas = calculate_excess_blob_gas(parent_header)
368
    if header.excess_blob_gas != excess_blob_gas:
369
        raise InvalidBlock
370
371
    if header.gas_used > header.gas_limit:
372
        raise InvalidBlock
373
374
    expected_base_fee_per_gas = calculate_base_fee_per_gas(
375
        header.gas_limit,
376
        parent_header.gas_limit,
377
        parent_header.gas_used,
378
        parent_header.base_fee_per_gas,
379
    )
380
    if expected_base_fee_per_gas != header.base_fee_per_gas:
381
        raise InvalidBlock
382
    if header.timestamp <= parent_header.timestamp:
383
        raise InvalidBlock
384
    if header.number != parent_header.number + Uint(1):
385
        raise InvalidBlock
386
    if len(header.extra_data) > 32:
387
        raise InvalidBlock
388
    if header.difficulty != 0:
389
        raise InvalidBlock
390
    if header.nonce != b"\x00\x00\x00\x00\x00\x00\x00\x00":
391
        raise InvalidBlock
392
    if header.ommers_hash != EMPTY_OMMER_HASH:
393
        raise InvalidBlock
394
395
    block_parent_hash = keccak256(rlp.encode(parent_header))
396
    if header.parent_hash != block_parent_hash:
397
        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]:
406
    <snip>
464
    gas_available = block_env.block_gas_limit - block_output.block_gas_used
465
    blob_gas_available = MAX_BLOB_GAS_PER_BLOCK - block_output.blob_gas_used
466
467
    if tx.gas > gas_available:
468
        raise GasUsedExceedsLimitError("gas used exceeds limit")
469
470
    tx_blob_gas_used = calculate_total_blob_gas(tx)
471
    if tx_blob_gas_used > blob_gas_available:
472
        raise BlobGasLimitExceededError("blob gas limit exceeded")
473
474
    sender_address = recover_sender(block_env.chain_id, tx)
475
    sender_account = get_account(tx_state, sender_address)
476
451
    if isinstance(tx, (FeeMarketTransaction, BlobTransaction)):
477
    if isinstance(
478
        tx, (FeeMarketTransaction, BlobTransaction, SetCodeTransaction)
479
    ):
480
        if tx.max_fee_per_gas < tx.max_priority_fee_per_gas:
481
            raise PriorityFeeGreaterThanMaxFeeError(
482
                "priority fee greater than max fee"
483
            )
484
        if tx.max_fee_per_gas < block_env.base_fee_per_gas:
485
            raise InsufficientMaxFeePerGasError(
486
                tx.max_fee_per_gas, block_env.base_fee_per_gas
487
            )
488
489
        priority_fee_per_gas = min(
490
            tx.max_priority_fee_per_gas,
491
            tx.max_fee_per_gas - block_env.base_fee_per_gas,
492
        )
493
        effective_gas_price = priority_fee_per_gas + block_env.base_fee_per_gas
494
        max_gas_fee = tx.gas * tx.max_fee_per_gas
495
    else:
496
        if tx.gas_price < block_env.base_fee_per_gas:
497
            raise InvalidBlock
498
        effective_gas_price = tx.gas_price
499
        max_gas_fee = tx.gas * tx.gas_price
500
501
    if isinstance(tx, BlobTransaction):
474
        if not isinstance(tx.to, Address):
475
            raise TransactionTypeContractCreationError(tx)
476
        if len(tx.blob_versioned_hashes) == 0:
502
        if len(tx.blob_versioned_hashes) == 0:
503
            raise NoBlobDataError("no blob data in transaction")
504
        for blob_versioned_hash in tx.blob_versioned_hashes:
505
            if blob_versioned_hash[0:1] != VERSIONED_HASH_VERSION_KZG:
506
                raise InvalidBlobVersionedHashError(
507
                    "invalid blob versioned hash"
508
                )
509
510
        blob_gas_price = calculate_blob_gas_price(block_env.excess_blob_gas)
511
        if Uint(tx.max_fee_per_blob_gas) < blob_gas_price:
512
            raise InsufficientMaxFeePerBlobGasError(
513
                "insufficient max fee per blob gas"
514
            )
515
516
        max_gas_fee += Uint(calculate_total_blob_gas(tx)) * Uint(
517
            tx.max_fee_per_blob_gas
518
        )
519
        blob_versioned_hashes = tx.blob_versioned_hashes
520
    else:
521
        blob_versioned_hashes = ()
522
523
    if isinstance(tx, (BlobTransaction, SetCodeTransaction)):
524
        if not isinstance(tx.to, Address):
525
            raise TransactionTypeContractCreationError(tx)
526
527
    if isinstance(tx, SetCodeTransaction):
528
        if not any(tx.authorizations):
529
            raise EmptyAuthorizationListError("empty authorization list")
530
531
    if sender_account.nonce > Uint(tx.nonce):
532
        raise NonceMismatchError("nonce too low")
533
    elif sender_account.nonce < Uint(tx.nonce):
534
        raise NonceMismatchError("nonce too high")
535
536
    if Uint(sender_account.balance) < max_gas_fee + Uint(tx.value):
537
        raise InsufficientBalanceError("insufficient sender balance")
502
    if sender_account.code_hash != EMPTY_CODE_HASH:
538
    sender_code = get_code(tx_state, sender_account.code_hash)
539
    if sender_account.code_hash != EMPTY_CODE_HASH and not is_valid_delegation(
540
        sender_code
541
    ):
542
        raise InvalidSenderError("not EOA")
543
544
    return (
545
        sender_address,
546
        effective_gas_price,
547
        blob_versioned_hashes,
548
        tx_blob_gas_used,
549
    )

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:
558
    <snip>
579
    receipt = Receipt(
580
        succeeded=error is None,
581
        cumulative_gas_used=cumulative_gas_used,
582
        bloom=logs_bloom(logs),
583
        logs=logs,
584
    )
585
586
    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:
594
    <snip>
613
    # Pre-check that the system contract has code. We use a throwaway
614
    # TransactionState here that is *never* propagated back to BlockState
615
    # (no incorporate_tx_into_block call); the same get_account / get_code
616
    # lookups are performed and properly tracked by
617
    # process_unchecked_system_transaction below, which this function
618
    # always calls. Reading via a TransactionState (rather than directly
619
    # against pre_state) lets us see system contracts deployed earlier in
620
    # the same block — see EIP-7002 and EIP-7251 for this edge case.
621
    untracked_state = TransactionState(parent=block_env.state)
622
    system_contract_code = get_code(
623
        untracked_state,
624
        get_account(untracked_state, target_address).code_hash,
625
    )
626
627
    if len(system_contract_code) == 0:
628
        raise InvalidBlock(
629
            f"System contract address {target_address.hex()} does not "
630
            "contain code"
631
        )
632
633
    system_tx_output = process_unchecked_system_transaction(
634
        block_env,
635
        target_address,
636
        data,
637
    )
638
639
    if system_tx_output.error:
640
        raise InvalidBlock(
641
            f"System contract ({target_address.hex()}) call failed: "
642
            f"{system_tx_output.error}"
643
        )
644
645
    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:
653
    <snip>
672
    system_tx_state = TransactionState(parent=block_env.state)
673
    system_contract_code = get_code(
674
        system_tx_state,
675
        get_account(system_tx_state, target_address).code_hash,
676
    )
677
678
    tx_env = vm.TransactionEnvironment(
679
        origin=SYSTEM_ADDRESS,
680
        gas_price=block_env.base_fee_per_gas,
681
        gas=SYSTEM_TRANSACTION_GAS,
682
        access_list_addresses=set(),
683
        access_list_storage_keys=set(),
684
        state=system_tx_state,
685
        blob_versioned_hashes=(),
686
        authorizations=(),
687
        index_in_block=None,
688
        tx_hash=None,
689
    )
690
691
    system_tx_message = Message(
692
        block_env=block_env,
693
        tx_env=tx_env,
694
        caller=SYSTEM_ADDRESS,
695
        target=target_address,
696
        gas=SYSTEM_TRANSACTION_GAS,
697
        value=U256(0),
698
        data=data,
699
        code=system_contract_code,
700
        depth=Uint(0),
701
        current_target=target_address,
702
        code_address=target_address,
703
        should_transfer_value=False,
704
        is_static=False,
705
        accessed_addresses=set(),
706
        accessed_storage_keys=set(),
707
        disable_precompiles=False,
708
        parent_evm=None,
709
    )
710
711
    system_tx_output = process_message_call(system_tx_message)
712
713
    incorporate_tx_into_block(system_tx_state)
714
715
    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:
723
    <snip>
748
    block_output = vm.BlockOutput()
749
750
    process_unchecked_system_transaction(
751
        block_env=block_env,
752
        target_address=BEACON_ROOTS_ADDRESS,
753
        data=block_env.parent_beacon_block_root,
754
    )
755
756
    process_unchecked_system_transaction(
757
        block_env=block_env,
758
        target_address=HISTORY_STORAGE_ADDRESS,
759
        data=block_env.block_hashes[-1],  # The parent hash
760
    )
761
762
    for i, tx in enumerate(map(decode_transaction, transactions)):
763
        process_transaction(block_env, block_output, tx, Uint(i))
764
765
    process_withdrawals(block_env, block_output, withdrawals)
766
767
    process_general_purpose_requests(
768
        block_env=block_env,
769
        block_output=block_output,
770
    )
771
772
    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:
779
    <snip>
790
    # Requests are to be in ascending order of request type
791
    deposit_requests = parse_deposit_requests(block_output)
792
    requests_from_execution = block_output.requests
793
    if len(deposit_requests) > 0:
794
        requests_from_execution.append(DEPOSIT_REQUEST_TYPE + deposit_requests)
795
796
    system_withdrawal_tx_output = process_checked_system_transaction(
797
        block_env=block_env,
798
        target_address=WITHDRAWAL_REQUEST_PREDEPLOY_ADDRESS,
799
        data=b"",
800
    )
801
802
    if len(system_withdrawal_tx_output.return_data) > 0:
803
        requests_from_execution.append(
804
            WITHDRAWAL_REQUEST_TYPE + system_withdrawal_tx_output.return_data
805
        )
806
807
    system_consolidation_tx_output = process_checked_system_transaction(
808
        block_env=block_env,
809
        target_address=CONSOLIDATION_REQUEST_PREDEPLOY_ADDRESS,
810
        data=b"",
811
    )
812
813
    if len(system_consolidation_tx_output.return_data) > 0:
814
        requests_from_execution.append(
815
            CONSOLIDATION_REQUEST_TYPE
816
            + system_consolidation_tx_output.return_data
817
        )

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:
826
    <snip>
850
    tx_state = TransactionState(parent=block_env.state)
851
852
    trie_set(
853
        block_output.transactions_trie,
854
        rlp.encode(index),
855
        encode_transaction(tx),
856
    )
857
702
    intrinsic_gas = validate_transaction(tx)
858
    intrinsic = validate_transaction(tx)
859
860
    (
861
        sender,
862
        effective_gas_price,
863
        blob_versioned_hashes,
864
        tx_blob_gas_used,
865
    ) = check_transaction(
866
        block_env=block_env,
867
        block_output=block_output,
868
        tx=tx,
869
        tx_state=tx_state,
870
    )
871
872
    sender_account = get_account(tx_state, sender)
873
874
    if isinstance(tx, BlobTransaction):
875
        blob_gas_fee = calculate_data_fee(block_env.excess_blob_gas, tx)
876
    else:
877
        blob_gas_fee = Uint(0)
878
879
    effective_gas_fee = tx.gas * effective_gas_price
880
725
    gas = tx.gas - intrinsic_gas
881
    gas = tx.gas - intrinsic.regular
882
    increment_nonce(tx_state, sender)
883
884
    sender_balance_after_gas_fee = (
885
        Uint(sender_account.balance) - effective_gas_fee - blob_gas_fee
886
    )
887
    set_account_balance(tx_state, sender, U256(sender_balance_after_gas_fee))
888
889
    access_list_addresses = set()
890
    access_list_storage_keys = set()
891
    access_list_addresses.add(block_env.coinbase)
736
    if isinstance(
737
        tx, (AccessListTransaction, FeeMarketTransaction, BlobTransaction)
738
    ):
892
    if has_access_list(tx):
893
        for access in tx.access_list:
894
            access_list_addresses.add(access.account)
895
            for slot in access.slots:
896
                access_list_storage_keys.add((access.account, slot))
897
898
    authorizations: Tuple[Authorization, ...] = ()
899
    if isinstance(tx, SetCodeTransaction):
900
        authorizations = tx.authorizations
901
902
    tx_env = vm.TransactionEnvironment(
903
        origin=sender,
904
        gas_price=effective_gas_price,
905
        gas=gas,
906
        access_list_addresses=access_list_addresses,
907
        access_list_storage_keys=access_list_storage_keys,
908
        state=tx_state,
909
        blob_versioned_hashes=blob_versioned_hashes,
910
        authorizations=authorizations,
911
        index_in_block=index,
912
        tx_hash=get_transaction_hash(encode_transaction(tx)),
913
    )
914
915
    message = prepare_message(block_env, tx_env, tx)
916
917
    tx_output = process_message_call(message)
918
760
    tx_gas_used_before_refund = tx.gas - tx_output.gas_left
919
    # For EIP-7623 we first calculate the execution_gas_used, which includes
920
    # the execution gas refund.
921
    tx_gas_used_before_refund = tx.gas - tx_output.gas_left
922
    tx_gas_refund = min(
923
        tx_gas_used_before_refund // Uint(5), Uint(tx_output.refund_counter)
924
    )
925
    tx_gas_used_after_refund = tx_gas_used_before_refund - tx_gas_refund
926
927
    # Transactions with less execution_gas_used than the floor pay at the
928
    # floor cost.
929
    tx_gas_used_after_refund = max(
930
        tx_gas_used_after_refund, intrinsic.calldata_floor
931
    )
932
933
    tx_gas_left = tx.gas - tx_gas_used_after_refund
934
    gas_refund_amount = tx_gas_left * effective_gas_price
935
936
    # For non-1559 transactions effective_gas_price == tx.gas_price
937
    priority_fee_per_gas = effective_gas_price - block_env.base_fee_per_gas
938
    transaction_fee = tx_gas_used_after_refund * priority_fee_per_gas
939
940
    # refund gas
941
    create_ether(tx_state, sender, U256(gas_refund_amount))
942
943
    # transfer miner fees
944
    create_ether(tx_state, block_env.coinbase, U256(transaction_fee))
945
946
    for address in tx_output.accounts_to_delete:
947
        destroy_account(tx_state, address)
948
949
    block_output.block_gas_used += tx_gas_used_after_refund
950
    block_output.blob_gas_used += tx_blob_gas_used
951
952
    receipt = make_receipt(
953
        tx, tx_output.error, block_output.block_gas_used, tx_output.logs
954
    )
955
956
    receipt_key = rlp.encode(Uint(index))
957
    block_output.receipt_keys += (receipt_key,)
958
959
    trie_set(
960
        block_output.receipts_trie,
961
        receipt_key,
962
        receipt,
963
    )
964
965
    block_output.block_logs += tx_output.logs
966
967
    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:
975
    <snip>
978
    wd_state = TransactionState(parent=block_env.state)
979
980
    for i, wd in enumerate(withdrawals):
981
        trie_set(
982
            block_output.withdrawals_trie,
983
            rlp.encode(Uint(i)),
984
            rlp.encode(wd),
985
        )
986
987
        create_ether(wd_state, wd.address, wd.amount * U256(10**9))
988
989
    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:
993
    <snip>
1021
    max_adjustment_delta = parent_gas_limit // GasCosts.LIMIT_ADJUSTMENT_FACTOR
1022
    if gas_limit >= parent_gas_limit + max_adjustment_delta:
1023
        return False
1024
    if gas_limit <= parent_gas_limit - max_adjustment_delta:
1025
        return False
1026
    if gas_limit < GasCosts.LIMIT_MINIMUM:
1027
        return False
1028
1029
    return True