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

76
BLOCK_REWARD = U256(2 * 10**18)

BASE_FEE_MAX_CHANGE_DENOMINATOR

73
BASE_FEE_MAX_CHANGE_DENOMINATOR = Uint(8)

ELASTICITY_MULTIPLIER

74
ELASTICITY_MULTIPLIER = Uint(2)

MINIMUM_DIFFICULTY

79
MINIMUM_DIFFICULTY = Uint(131072)

MAX_OMMER_DEPTH

80
MAX_OMMER_DEPTH = Uint(6)

BOMB_DELAY_BLOCKS

81
BOMB_DELAY_BLOCKS = 11400000

EMPTY_OMMER_HASH

75
EMPTY_OMMER_HASH = keccak256(rlp.encode([]))

BlockChain

History and current state of the block chain.

78
@final
79
@dataclass
class BlockChain:

blocks

85
    blocks: List[Block]

state

86
    state: State

chain_id

87
    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:
91
    <snip>
110
    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]:
114
    <snip>
134
    recent_blocks = chain.blocks[-255:]
135
    # TODO: This function has not been tested rigorously
136
    if len(recent_blocks) == 0:
137
        return []
138
139
    recent_block_hashes = []
140
141
    for block in recent_blocks:
142
        prev_block_hash = block.header.parent_hash
143
        recent_block_hashes.append(prev_block_hash)
144
145
    # We are computing the hash only for the most recent block and not for
146
    # the rest of the blocks as they have successors which have the hash of
147
    # the current block as parent hash.
148
    most_recent_block_hash = keccak256(rlp.encode(recent_blocks[-1].header))
149
    recent_block_hashes.append(most_recent_block_hash)
150
151
    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:
155
    <snip>
177
    validate_header(chain, block.header)
185
    validate_ommers(block.ommers, block.header, chain)
178
    if block.ommers != ():
179
        raise InvalidBlock
180
181
    block_state = BlockState(pre_state=chain.state)
182
183
    block_env = vm.BlockEnvironment(
184
        chain_id=chain.chain_id,
185
        state=block_state,
186
        block_gas_limit=block.header.gas_limit,
187
        block_hashes=get_last_256_block_hashes(chain),
188
        coinbase=block.header.coinbase,
189
        number=block.header.number,
190
        base_fee_per_gas=block.header.base_fee_per_gas,
191
        time=block.header.timestamp,
198
        difficulty=block.header.difficulty,
192
        prev_randao=block.header.prev_randao,
193
    )
194
195
    block_output = apply_body(
196
        block_env=block_env,
197
        transactions=block.transactions,
204
        ommers=block.ommers,
198
    )
199
    block_diff = extract_block_diff(block_state)
200
    block_state_root, _ = chain.state.compute_state_root_and_trie_changes(
201
        block_diff.account_changes,
202
        block_diff.storage_changes,
203
        block_diff.storage_clears,
204
    )
205
    transactions_root = root(block_output.transactions_trie)
206
    receipt_root = root(block_output.receipts_trie)
207
    block_logs_bloom = logs_bloom(block_output.block_logs)
208
209
    if block_output.block_gas_used != block.header.gas_used:
210
        raise InvalidBlock(
211
            f"{block_output.block_gas_used} != {block.header.gas_used}"
212
        )
213
    if transactions_root != block.header.transactions_root:
214
        raise InvalidBlock
215
    if block_state_root != block.header.state_root:
216
        raise InvalidBlock
217
    if receipt_root != block.header.receipt_root:
218
        raise InvalidBlock
219
    if block_logs_bloom != block.header.bloom:
220
        raise InvalidBlock
221
222
    apply_changes_to_state(chain.state, block_diff)
223
    chain.blocks.append(block)
224
    if len(chain.blocks) > 255:
225
        # Real clients have to store more blocks to deal with reorgs, but the
226
        # protocol only requires the last 255
227
        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:
236
    <snip>
256
    parent_gas_target = parent_gas_limit // ELASTICITY_MULTIPLIER
257
    if not check_gas_limit(block_gas_limit, parent_gas_limit):
258
        raise InvalidBlock
259
260
    if parent_gas_used == parent_gas_target:
261
        expected_base_fee_per_gas = parent_base_fee_per_gas
262
    elif parent_gas_used > parent_gas_target:
263
        gas_used_delta = parent_gas_used - parent_gas_target
264
265
        parent_fee_gas_delta = parent_base_fee_per_gas * gas_used_delta
266
        target_fee_gas_delta = parent_fee_gas_delta // parent_gas_target
267
268
        base_fee_per_gas_delta = max(
269
            target_fee_gas_delta // BASE_FEE_MAX_CHANGE_DENOMINATOR,
270
            Uint(1),
271
        )
272
273
        expected_base_fee_per_gas = (
274
            parent_base_fee_per_gas + base_fee_per_gas_delta
275
        )
276
    else:
277
        gas_used_delta = parent_gas_target - parent_gas_used
278
279
        parent_fee_gas_delta = parent_base_fee_per_gas * gas_used_delta
280
        target_fee_gas_delta = parent_fee_gas_delta // parent_gas_target
281
282
        base_fee_per_gas_delta = (
283
            target_fee_gas_delta // BASE_FEE_MAX_CHANGE_DENOMINATOR
284
        )
285
286
        expected_base_fee_per_gas = (
287
            parent_base_fee_per_gas - base_fee_per_gas_delta
288
        )
289
290
    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:
294
    <snip>
312
    if header.number < Uint(1):
313
        raise InvalidBlock
321
    parent_header_number = header.number - Uint(1)
322
    first_block_number = chain.blocks[0].header.number
323
    last_block_number = chain.blocks[-1].header.number
314
325
    if (
326
        parent_header_number < first_block_number
327
        or parent_header_number > last_block_number
328
    ):
329
        raise InvalidBlock
330
331
    parent_header = chain.blocks[
332
        parent_header_number - first_block_number
333
    ].header
315
    parent_header = chain.blocks[-1].header
316
317
    if header.gas_used > header.gas_limit:
318
        raise InvalidBlock
319
320
    expected_base_fee_per_gas = calculate_base_fee_per_gas(
321
        header.gas_limit,
322
        parent_header.gas_limit,
323
        parent_header.gas_used,
324
        parent_header.base_fee_per_gas,
325
    )
326
    if expected_base_fee_per_gas != header.base_fee_per_gas:
327
        raise InvalidBlock
346
347
    parent_has_ommers = parent_header.ommers_hash != EMPTY_OMMER_HASH
328
    if header.timestamp <= parent_header.timestamp:
329
        raise InvalidBlock
330
    if header.number != parent_header.number + Uint(1):
331
        raise InvalidBlock
332
    if len(header.extra_data) > 32:
333
        raise InvalidBlock
354
355
    block_difficulty = calculate_block_difficulty(
356
        header.number,
357
        header.timestamp,
358
        parent_header.timestamp,
359
        parent_header.difficulty,
360
        parent_has_ommers,
361
    )
362
    if header.difficulty != block_difficulty:
334
    if header.difficulty != 0:
335
        raise InvalidBlock
336
    if header.nonce != b"\x00\x00\x00\x00\x00\x00\x00\x00":
337
        raise InvalidBlock
338
    if header.ommers_hash != EMPTY_OMMER_HASH:
339
        raise InvalidBlock
340
341
    block_parent_hash = keccak256(rlp.encode(parent_header))
342
    if header.parent_hash != block_parent_hash:
367
        raise InvalidBlock
368
369
    validate_proof_of_work(header)
343
        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:
373
    <snip>
396
    header_data_without_pow_artefacts = (
397
        header.parent_hash,
398
        header.ommers_hash,
399
        header.coinbase,
400
        header.state_root,
401
        header.transactions_root,
402
        header.receipt_root,
403
        header.bloom,
404
        header.difficulty,
405
        header.number,
406
        header.gas_limit,
407
        header.gas_used,
408
        header.timestamp,
409
        header.extra_data,
410
        header.base_fee_per_gas,
411
    )
412
413
    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:
417
    <snip>
432
    header_hash = generate_header_hash_for_pow(header)
433
    # TODO: Memoize this somewhere and read from that data instead of
434
    # calculating cache for every block validation.
435
    cache = generate_cache(header.number)
436
    mix_digest, result = hashimoto_light(
437
        header_hash, header.nonce, cache, dataset_size(header.number)
438
    )
439
    if mix_digest != header.mix_digest:
440
        raise InvalidBlock
441
442
    limit = Uint(U256.MAX_VALUE) + Uint(1)
443
    if Uint.from_be_bytes(result) > (limit // header.difficulty):
444
        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.

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, ​​tx_state: TransactionState) -> Tuple[Address, Uint]:
352
    <snip>
391
    gas_available = block_env.block_gas_limit - block_output.block_gas_used
392
    if tx.gas > gas_available:
393
        raise GasUsedExceedsLimitError("gas used exceeds limit")
394
    tx_chain_id = chain_id(tx)
395
    if tx_chain_id is not None and tx_chain_id != block_env.chain_id:
396
        raise WrongChainIdError(
397
            expected=block_env.chain_id,
398
            actual=tx_chain_id,
399
        )
400
401
    sender_address = recover_sender(tx)
402
    sender_account = get_account(tx_state, sender_address)
403
404
    if isinstance(tx, FeeMarketTransaction):
405
        if tx.max_fee_per_gas < tx.max_priority_fee_per_gas:
406
            raise PriorityFeeGreaterThanMaxFeeError(
407
                "priority fee greater than max fee"
408
            )
409
        if tx.max_fee_per_gas < block_env.base_fee_per_gas:
410
            raise InsufficientMaxFeePerGasError(
411
                tx.max_fee_per_gas, block_env.base_fee_per_gas
412
            )
413
414
        priority_fee_per_gas = min(
415
            tx.max_priority_fee_per_gas,
416
            tx.max_fee_per_gas - block_env.base_fee_per_gas,
417
        )
418
        effective_gas_price = priority_fee_per_gas + block_env.base_fee_per_gas
419
        max_gas_fee = tx.gas * tx.max_fee_per_gas
420
    else:
421
        if tx.gas_price < block_env.base_fee_per_gas:
422
            raise InvalidBlock
423
        effective_gas_price = tx.gas_price
424
        max_gas_fee = tx.gas * tx.gas_price
425
426
    if sender_account.nonce > Uint(tx.nonce):
427
        raise NonceMismatchError("nonce too low")
428
    elif sender_account.nonce < Uint(tx.nonce):
429
        raise NonceMismatchError("nonce too high")
430
    if Uint(sender_account.balance) < max_gas_fee + Uint(tx.value):
431
        raise InsufficientBalanceError("insufficient sender balance")
432
    if sender_account.code_hash != EMPTY_CODE_HASH:
433
        raise InvalidSenderError("not EOA")
434
435
    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:
444
    <snip>
465
    receipt = Receipt(
466
        succeeded=error is None,
467
        cumulative_gas_used=cumulative_gas_used,
468
        bloom=logs_bloom(logs),
469
        logs=logs,
470
    )
471
472
    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:
479
    <snip>
502
    block_output = vm.BlockOutput()
503
504
    for i, tx in enumerate(map(decode_transaction, transactions)):
505
        process_transaction(block_env, block_output, tx, Uint(i))
506
612
    pay_rewards(block_env, ommers)
613
507
    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:
620
    <snip>
642
    block_hash = keccak256(rlp.encode(block_header))
643
    if keccak256(rlp.encode(ommers)) != block_header.ommers_hash:
644
        raise InvalidBlock
645
646
    if len(ommers) == 0:
647
        # Nothing to validate
648
        return
649
650
    # Check that each ommer satisfies the constraints of a header
651
    for ommer in ommers:
652
        if Uint(1) > ommer.number or ommer.number >= block_header.number:
653
            raise InvalidBlock
654
        validate_header(chain, ommer)
655
    if len(ommers) > 2:
656
        raise InvalidBlock
657
658
    ommers_hashes = [keccak256(rlp.encode(ommer)) for ommer in ommers]
659
    if len(ommers_hashes) != len(set(ommers_hashes)):
660
        raise InvalidBlock
661
662
    recent_canonical_blocks = chain.blocks[-(MAX_OMMER_DEPTH + Uint(1)) :]
663
    recent_canonical_block_hashes = {
664
        keccak256(rlp.encode(block.header))
665
        for block in recent_canonical_blocks
666
    }
667
    recent_ommers_hashes: Set[Hash32] = set()
668
    for block in recent_canonical_blocks:
669
        recent_ommers_hashes = recent_ommers_hashes.union(
670
            {keccak256(rlp.encode(ommer)) for ommer in block.ommers}
671
        )
672
673
    for ommer_index, ommer in enumerate(ommers):
674
        ommer_hash = ommers_hashes[ommer_index]
675
        if ommer_hash == block_hash:
676
            raise InvalidBlock
677
        if ommer_hash in recent_canonical_block_hashes:
678
            raise InvalidBlock
679
        if ommer_hash in recent_ommers_hashes:
680
            raise InvalidBlock
681
682
        # Ommer age with respect to the current block. For example, an age of
683
        # 1 indicates that the ommer is a sibling of previous block.
684
        ommer_age = block_header.number - ommer.number
685
        if Uint(1) > ommer_age or ommer_age > MAX_OMMER_DEPTH:
686
            raise InvalidBlock
687
        if ommer.parent_hash not in recent_canonical_block_hashes:
688
            raise InvalidBlock
689
        if ommer.parent_hash == block_header.parent_hash:
690
            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

block_env : The block scoped environment. ommers : List of ommers mentioned in the current block.

def pay_rewards(block_env: ethereum.forks.gray_glacier.vm.BlockEnvironment, ​​ommers: Tuple[Header, ...]) -> None:
697
    <snip>
719
    rewards_state = TransactionState(parent=block_env.state)
720
    ommer_count = U256(len(ommers))
721
    miner_reward = BLOCK_REWARD + (ommer_count * (BLOCK_REWARD // U256(32)))
722
    create_ether(rewards_state, block_env.coinbase, miner_reward)
723
724
    for ommer in ommers:
725
        # Ommer age with respect to the current block.
726
        ommer_age = U256(block_env.number - ommer.number)
727
        ommer_miner_reward = ((U256(8) - ommer_age) * BLOCK_REWARD) // U256(8)
728
        create_ether(rewards_state, ommer.coinbase, ommer_miner_reward)
729
730
    incorporate_tx_into_block(rewards_state)

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:
516
    <snip>
540
    tx_state = TransactionState(parent=block_env.state)
541
542
    trie_set(
543
        block_output.transactions_trie,
544
        rlp.encode(index),
545
        encode_transaction(tx),
546
    )
547
548
    intrinsic_gas = validate_transaction(tx)
549
550
    (
551
        sender,
552
        effective_gas_price,
553
    ) = check_transaction(
554
        block_env=block_env,
555
        block_output=block_output,
556
        tx=tx,
557
        tx_state=tx_state,
558
    )
559
560
    sender_account = get_account(tx_state, sender)
561
562
    effective_gas_fee = tx.gas * effective_gas_price
563
564
    gas = tx.gas - intrinsic_gas
565
    increment_nonce(tx_state, sender)
566
567
    sender_balance_after_gas_fee = (
568
        Uint(sender_account.balance) - effective_gas_fee
569
    )
570
    set_account_balance(tx_state, sender, U256(sender_balance_after_gas_fee))
571
572
    access_list_addresses = set()
573
    access_list_storage_keys = set()
574
    if isinstance(tx, (AccessListTransaction, FeeMarketTransaction)):
575
        for access in tx.access_list:
576
            access_list_addresses.add(access.account)
577
            for slot in access.slots:
578
                access_list_storage_keys.add((access.account, slot))
579
580
    tx_env = vm.TransactionEnvironment(
581
        origin=sender,
582
        gas_price=effective_gas_price,
583
        gas=gas,
584
        access_list_addresses=access_list_addresses,
585
        access_list_storage_keys=access_list_storage_keys,
586
        state=tx_state,
587
        index_in_block=index,
588
        tx_hash=get_transaction_hash(encode_transaction(tx)),
589
    )
590
591
    message = prepare_message(block_env, tx_env, tx)
592
593
    tx_output = process_message_call(message)
594
595
    tx_gas_used_before_refund = tx.gas - tx_output.gas_left
596
    tx_gas_refund = min(
597
        tx_gas_used_before_refund // Uint(5), Uint(tx_output.refund_counter)
598
    )
599
    tx_gas_used_after_refund = tx_gas_used_before_refund - tx_gas_refund
600
    tx_gas_left = tx.gas - tx_gas_used_after_refund
601
    gas_refund_amount = tx_gas_left * effective_gas_price
602
603
    # For non-1559 transactions effective_gas_price == tx.gas_price
604
    priority_fee_per_gas = effective_gas_price - block_env.base_fee_per_gas
605
    transaction_fee = tx_gas_used_after_refund * priority_fee_per_gas
606
607
    # refund gas
608
    create_ether(tx_state, sender, U256(gas_refund_amount))
609
610
    # transfer miner fees
834
    coinbase_balance_after_mining_fee = get_account(
835
        tx_state, block_env.coinbase
836
    ).balance + U256(transaction_fee)
837
    if coinbase_balance_after_mining_fee != 0:
838
        set_account_balance(
839
            tx_state,
840
            block_env.coinbase,
841
            coinbase_balance_after_mining_fee,
842
        )
843
    elif account_exists_and_is_empty(tx_state, block_env.coinbase):
844
        destroy_account(tx_state, block_env.coinbase)
611
    create_ether(tx_state, block_env.coinbase, U256(transaction_fee))
612
613
    for address in tx_output.accounts_to_delete:
614
        destroy_account(tx_state, address)
848
849
    destroy_touched_empty_accounts(tx_state, tx_output.touched_accounts)
615
616
    block_output.block_gas_used += tx_gas_used_after_refund
617
618
    receipt = make_receipt(
619
        tx, tx_output.error, block_output.block_gas_used, tx_output.logs
620
    )
621
622
    receipt_key = rlp.encode(Uint(index))
623
    block_output.receipt_keys += (receipt_key,)
624
625
    trie_set(
626
        block_output.receipts_trie,
627
        receipt_key,
628
        receipt,
629
    )
630
631
    block_output.block_logs += tx_output.logs
632
633
    incorporate_tx_into_block(tx_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 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:
637
    <snip>
665
    max_adjustment_delta = parent_gas_limit // GasCosts.LIMIT_ADJUSTMENT_FACTOR
666
    if gas_limit >= parent_gas_limit + max_adjustment_delta:
667
        return False
668
    if gas_limit <= parent_gas_limit - max_adjustment_delta:
669
        return False
670
    if gas_limit < GasCosts.LIMIT_MINIMUM:
671
        return False
672
673
    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:
918
    <snip>
957
    offset = (
958
        int(parent_difficulty)
959
        // 2048
960
        * max(
961
            (2 if parent_has_ommers else 1)
962
            - int(block_timestamp - parent_timestamp) // 9,
963
            -99,
964
        )
965
    )
966
    difficulty = int(parent_difficulty) + offset
967
    # Historical Note: The difficulty bomb was not present in Ethereum at the
968
    # start of Frontier, but was added shortly after launch. However since the
969
    # bomb has no effect prior to block 200000 we pretend it existed from
970
    # genesis.
971
    # See https://github.com/ethereum/go-ethereum/pull/1588
972
    num_bomb_periods = ((int(block_number) - BOMB_DELAY_BLOCKS) // 100000) - 2
973
    if num_bomb_periods >= 0:
974
        difficulty += 2**num_bomb_periods
975
976
    # Some clients raise the difficulty to `MINIMUM_DIFFICULTY` prior to adding
977
    # the bomb. This bug does not matter because the difficulty is always much
978
    # greater than `MINIMUM_DIFFICULTY` on Mainnet.
979
    return Uint(max(difficulty, int(MINIMUM_DIFFICULTY)))