ethereum.gray_glacier.forkethereum.paris.fork

Ethereum Specification ^^^^^^^^^^^^^^^^^^^^^^

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

Introduction

Entry point for the Ethereum specification.

BLOCK_REWARD

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BLOCK_REWARD = U256(2 * 10**18)

BASE_FEE_MAX_CHANGE_DENOMINATOR

57
BASE_FEE_MAX_CHANGE_DENOMINATOR = Uint(8)

ELASTICITY_MULTIPLIER

58
ELASTICITY_MULTIPLIER = Uint(2)

GAS_LIMIT_ADJUSTMENT_FACTOR

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GAS_LIMIT_ADJUSTMENT_FACTOR = Uint(1024)

GAS_LIMIT_MINIMUM

60
GAS_LIMIT_MINIMUM = Uint(5000)

MINIMUM_DIFFICULTY

65
MINIMUM_DIFFICULTY = Uint(131072)

MAX_OMMER_DEPTH

66
MAX_OMMER_DEPTH = Uint(6)

BOMB_DELAY_BLOCKS

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BOMB_DELAY_BLOCKS = 11400000

EMPTY_OMMER_HASH

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

BlockChain

History and current state of the block chain.

64
@dataclass
class BlockChain:

blocks

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    blocks: List[Block]

state

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    state: State

chain_id

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    chain_id: U64

apply_fork

Transforms the state from the previous hard fork (old) into the block chain object for this hard fork and returns it.

When forks need to implement an irregular state transition, this function is used to handle the irregularity. See the :ref:DAO Fork <dao-fork> for an example.

Parameters

old : Previous block chain object.

Returns

new : BlockChain Upgraded block chain object for this hard fork.

def apply_fork(old: BlockChain) -> BlockChain:
76
    """
77
    Transforms the state from the previous hard fork (`old`) into the block
78
    chain object for this hard fork and returns it.
79
80
    When forks need to implement an irregular state transition, this function
81
    is used to handle the irregularity. See the :ref:`DAO Fork <dao-fork>` for
82
    an example.
83
84
    Parameters
85
    ----------
86
    old :
87
        Previous block chain object.
88
89
    Returns
90
    -------
91
    new : `BlockChain`
92
        Upgraded block chain object for this hard fork.
93
    """
94
    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]:
98
    """
99
    Obtain the list of hashes of the previous 256 blocks in order of
100
    increasing block number.
101
102
    This function will return less hashes for the first 256 blocks.
103
104
    The ``BLOCKHASH`` opcode needs to access the latest hashes on the chain,
105
    therefore this function retrieves them.
106
107
    Parameters
108
    ----------
109
    chain :
110
        History and current state.
111
112
    Returns
113
    -------
114
    recent_block_hashes : `List[Hash32]`
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        Hashes of the recent 256 blocks in order of increasing block number.
116
    """
117
    recent_blocks = chain.blocks[-255:]
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    # TODO: This function has not been tested rigorously
119
    if len(recent_blocks) == 0:
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        return []
121
122
    recent_block_hashes = []
123
124
    for block in recent_blocks:
125
        prev_block_hash = block.header.parent_hash
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        recent_block_hashes.append(prev_block_hash)
127
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    # We are computing the hash only for the most recent block and not for
129
    # the rest of the blocks as they have successors which have the hash of
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    # the current block as parent hash.
131
    most_recent_block_hash = keccak256(rlp.encode(recent_blocks[-1].header))
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    recent_block_hashes.append(most_recent_block_hash)
133
134
    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:
138
    """
139
    Attempts to apply a block to an existing block chain.
140
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    All parts of the block's contents need to be verified before being added
142
    to the chain. Blocks are verified by ensuring that the contents of the
143
    block make logical sense with the contents of the parent block. The
144
    information in the block's header must also match the corresponding
145
    information in the block.
146
147
    To implement Ethereum, in theory clients are only required to store the
148
    most recent 255 blocks of the chain since as far as execution is
149
    concerned, only those blocks are accessed. Practically, however, clients
150
    should store more blocks to handle reorgs.
151
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    Parameters
153
    ----------
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    chain :
155
        History and current state.
156
    block :
157
        Block to apply to `chain`.
158
    """
159
    validate_header(chain, block.header)
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    validate_ommers(block.ommers, block.header, chain)
160
    if block.ommers != ():
161
        raise InvalidBlock
162
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    block_env = vm.BlockEnvironment(
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        chain_id=chain.chain_id,
165
        state=chain.state,
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        block_gas_limit=block.header.gas_limit,
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        block_hashes=get_last_256_block_hashes(chain),
168
        coinbase=block.header.coinbase,
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        number=block.header.number,
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        base_fee_per_gas=block.header.base_fee_per_gas,
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        time=block.header.timestamp,
178
        difficulty=block.header.difficulty,
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        prev_randao=block.header.prev_randao,
173
    )
174
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    block_output = apply_body(
176
        block_env=block_env,
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        transactions=block.transactions,
184
        ommers=block.ommers,
178
    )
179
    block_state_root = state_root(block_env.state)
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    transactions_root = root(block_output.transactions_trie)
181
    receipt_root = root(block_output.receipts_trie)
182
    block_logs_bloom = logs_bloom(block_output.block_logs)
183
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    if block_output.block_gas_used != block.header.gas_used:
185
        raise InvalidBlock(
186
            f"{block_output.block_gas_used} != {block.header.gas_used}"
187
        )
188
    if transactions_root != block.header.transactions_root:
189
        raise InvalidBlock
190
    if block_state_root != block.header.state_root:
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        raise InvalidBlock
192
    if receipt_root != block.header.receipt_root:
193
        raise InvalidBlock
194
    if block_logs_bloom != block.header.bloom:
195
        raise InvalidBlock
196
197
    chain.blocks.append(block)
198
    if len(chain.blocks) > 255:
199
        # Real clients have to store more blocks to deal with reorgs, but the
200
        # protocol only requires the last 255
201
        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:
210
    """
211
    Calculates the base fee per gas for the block.
212
213
    Parameters
214
    ----------
215
    block_gas_limit :
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        Gas limit of the block for which the base fee is being calculated.
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    parent_gas_limit :
218
        Gas limit of the parent block.
219
    parent_gas_used :
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        Gas used in the parent block.
221
    parent_base_fee_per_gas :
222
        Base fee per gas of the parent block.
223
224
    Returns
225
    -------
226
    base_fee_per_gas : `Uint`
227
        Base fee per gas for the block.
228
    """
229
    parent_gas_target = parent_gas_limit // ELASTICITY_MULTIPLIER
230
    if not check_gas_limit(block_gas_limit, parent_gas_limit):
231
        raise InvalidBlock
232
233
    if parent_gas_used == parent_gas_target:
234
        expected_base_fee_per_gas = parent_base_fee_per_gas
235
    elif parent_gas_used > parent_gas_target:
236
        gas_used_delta = parent_gas_used - parent_gas_target
237
238
        parent_fee_gas_delta = parent_base_fee_per_gas * gas_used_delta
239
        target_fee_gas_delta = parent_fee_gas_delta // parent_gas_target
240
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        base_fee_per_gas_delta = max(
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            target_fee_gas_delta // BASE_FEE_MAX_CHANGE_DENOMINATOR,
243
            Uint(1),
244
        )
245
246
        expected_base_fee_per_gas = (
247
            parent_base_fee_per_gas + base_fee_per_gas_delta
248
        )
249
    else:
250
        gas_used_delta = parent_gas_target - parent_gas_used
251
252
        parent_fee_gas_delta = parent_base_fee_per_gas * gas_used_delta
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        target_fee_gas_delta = parent_fee_gas_delta // parent_gas_target
254
255
        base_fee_per_gas_delta = (
256
            target_fee_gas_delta // BASE_FEE_MAX_CHANGE_DENOMINATOR
257
        )
258
259
        expected_base_fee_per_gas = (
260
            parent_base_fee_per_gas - base_fee_per_gas_delta
261
        )
262
263
    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:
267
    """
268
    Verifies a block header.
269
270
    In order to consider a block's header valid, the logic for the
271
    quantities in the header should match the logic for the block itself.
272
    For example the header timestamp should be greater than the block's parent
273
    timestamp because the block was created *after* the parent block.
274
    Additionally, the block's number should be directly following the parent
275
    block's number since it is the next block in the sequence.
276
277
    Parameters
278
    ----------
279
    chain :
280
        History and current state.
281
    header :
282
        Header to check for correctness.
283
    """
284
    if header.number < Uint(1):
285
        raise InvalidBlock
293
    parent_header_number = header.number - Uint(1)
294
    first_block_number = chain.blocks[0].header.number
295
    last_block_number = chain.blocks[-1].header.number
286
297
    if (
298
        parent_header_number < first_block_number
299
        or parent_header_number > last_block_number
300
    ):
301
        raise InvalidBlock
302
303
    parent_header = chain.blocks[
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        parent_header_number - first_block_number
305
    ].header
287
    parent_header = chain.blocks[-1].header
288
289
    if header.gas_used > header.gas_limit:
290
        raise InvalidBlock
291
292
    expected_base_fee_per_gas = calculate_base_fee_per_gas(
293
        header.gas_limit,
294
        parent_header.gas_limit,
295
        parent_header.gas_used,
296
        parent_header.base_fee_per_gas,
297
    )
298
    if expected_base_fee_per_gas != header.base_fee_per_gas:
299
        raise InvalidBlock
318
319
    parent_has_ommers = parent_header.ommers_hash != EMPTY_OMMER_HASH
300
    if header.timestamp <= parent_header.timestamp:
301
        raise InvalidBlock
302
    if header.number != parent_header.number + Uint(1):
303
        raise InvalidBlock
304
    if len(header.extra_data) > 32:
305
        raise InvalidBlock
326
327
    block_difficulty = calculate_block_difficulty(
328
        header.number,
329
        header.timestamp,
330
        parent_header.timestamp,
331
        parent_header.difficulty,
332
        parent_has_ommers,
333
    )
334
    if header.difficulty != block_difficulty:
306
    if header.difficulty != 0:
307
        raise InvalidBlock
308
    if header.nonce != b"\x00\x00\x00\x00\x00\x00\x00\x00":
309
        raise InvalidBlock
310
    if header.ommers_hash != EMPTY_OMMER_HASH:
311
        raise InvalidBlock
312
313
    block_parent_hash = keccak256(rlp.encode(parent_header))
314
    if header.parent_hash != block_parent_hash:
339
        raise InvalidBlock
340
341
    validate_proof_of_work(header)
315
        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:
345
    """
346
    Generate rlp hash of the header which is to be used for Proof-of-Work
347
    verification.
348
349
    In other words, the PoW artefacts `mix_digest` and `nonce` are ignored
350
    while calculating this hash.
351
352
    A particular PoW is valid for a single hash, that hash is computed by
353
    this function. The `nonce` and `mix_digest` are omitted from this hash
354
    because they are being changed by miners in their search for a sufficient
355
    proof-of-work.
356
357
    Parameters
358
    ----------
359
    header :
360
        The header object for which the hash is to be generated.
361
362
    Returns
363
    -------
364
    hash : `Hash32`
365
        The PoW valid rlp hash of the passed in header.
366
    """
367
    header_data_without_pow_artefacts = (
368
        header.parent_hash,
369
        header.ommers_hash,
370
        header.coinbase,
371
        header.state_root,
372
        header.transactions_root,
373
        header.receipt_root,
374
        header.bloom,
375
        header.difficulty,
376
        header.number,
377
        header.gas_limit,
378
        header.gas_used,
379
        header.timestamp,
380
        header.extra_data,
381
        header.base_fee_per_gas,
382
    )
383
384
    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:
388
    """
389
    Validates the Proof of Work constraints.
390
391
    In order to verify that a miner's proof-of-work is valid for a block, a
392
    ``mix-digest`` and ``result`` are calculated using the ``hashimoto_light``
393
    hash function. The mix digest is a hash of the header and the nonce that
394
    is passed through and it confirms whether or not proof-of-work was done
395
    on the correct block. The result is the actual hash value of the block.
396
397
    Parameters
398
    ----------
399
    header :
400
        Header of interest.
401
    """
402
    header_hash = generate_header_hash_for_pow(header)
403
    # TODO: Memoize this somewhere and read from that data instead of
404
    # calculating cache for every block validation.
405
    cache = generate_cache(header.number)
406
    mix_digest, result = hashimoto_light(
407
        header_hash, header.nonce, cache, dataset_size(header.number)
408
    )
409
    if mix_digest != header.mix_digest:
410
        raise InvalidBlock
411
412
    limit = Uint(U256.MAX_VALUE) + Uint(1)
413
    if Uint.from_be_bytes(result) > (limit // header.difficulty):
414
        raise InvalidBlock

check_transaction

Check if the transaction is includable in the block.

Parameters

block_env : The block scoped environment. block_output : The block output for the current block. tx : The transaction.

Returns

sender_address : The sender of the transaction. effective_gas_price : The price to charge for gas when the transaction is executed.

Raises

InvalidBlock : If the transaction is not includable.

def check_transaction(block_env: ethereum.gray_glacier.vm.BlockEnvironmentethereum.paris.vm.BlockEnvironment, ​​block_output: ethereum.gray_glacier.vm.BlockOutputethereum.paris.vm.BlockOutput, ​​tx: Transaction) -> Tuple[Address, Uint]:
323
    """
324
    Check if the transaction is includable in the block.
325
326
    Parameters
327
    ----------
328
    block_env :
329
        The block scoped environment.
330
    block_output :
331
        The block output for the current block.
332
    tx :
333
        The transaction.
334
335
    Returns
336
    -------
337
    sender_address :
338
        The sender of the transaction.
339
    effective_gas_price :
340
        The price to charge for gas when the transaction is executed.
341
342
    Raises
343
    ------
344
    InvalidBlock :
345
        If the transaction is not includable.
346
    """
347
    gas_available = block_env.block_gas_limit - block_output.block_gas_used
348
    if tx.gas > gas_available:
349
        raise InvalidBlock
350
    sender_address = recover_sender(block_env.chain_id, tx)
351
    sender_account = get_account(block_env.state, sender_address)
352
353
    if isinstance(tx, FeeMarketTransaction):
354
        if tx.max_fee_per_gas < tx.max_priority_fee_per_gas:
355
            raise InvalidBlock
356
        if tx.max_fee_per_gas < block_env.base_fee_per_gas:
357
            raise InvalidBlock
358
359
        priority_fee_per_gas = min(
360
            tx.max_priority_fee_per_gas,
361
            tx.max_fee_per_gas - block_env.base_fee_per_gas,
362
        )
363
        effective_gas_price = priority_fee_per_gas + block_env.base_fee_per_gas
364
        max_gas_fee = tx.gas * tx.max_fee_per_gas
365
    else:
366
        if tx.gas_price < block_env.base_fee_per_gas:
367
            raise InvalidBlock
368
        effective_gas_price = tx.gas_price
369
        max_gas_fee = tx.gas * tx.gas_price
370
371
    if sender_account.nonce != tx.nonce:
372
        raise InvalidBlock
373
    if Uint(sender_account.balance) < max_gas_fee + Uint(tx.value):
374
        raise InvalidBlock
375
    if sender_account.code:
376
        raise InvalidSenderError("not EOA")
377
378
    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, ...]) -> Union[Bytes, Receipt]:
387
    """
388
    Make the receipt for a transaction that was executed.
389
390
    Parameters
391
    ----------
392
    tx :
393
        The executed transaction.
394
    error :
395
        Error in the top level frame of the transaction, if any.
396
    cumulative_gas_used :
397
        The total gas used so far in the block after the transaction was
398
        executed.
399
    logs :
400
        The logs produced by the transaction.
401
402
    Returns
403
    -------
404
    receipt :
405
        The receipt for the transaction.
406
    """
407
    receipt = Receipt(
408
        succeeded=error is None,
409
        cumulative_gas_used=cumulative_gas_used,
410
        bloom=logs_bloom(logs),
411
        logs=logs,
412
    )
413
414
    return encode_receipt(tx, receipt)

apply_body

Executes a block.

Many of the contents of a block are stored in data structures called tries. There is a transactions trie which is similar to a ledger of the transactions stored in the current block. There is also a receipts trie which stores the results of executing a transaction, like the post state and gas used. This function creates and executes the block that is to be added to the chain.

Parameters

block_env : The block scoped environment. transactions : Transactions included in the block. ommers : Headers of ancestor blocks which are not direct parents (formerly uncles.)

Returns

block_output : The block output for the current block.

def apply_body(block_env: ethereum.gray_glacier.vm.BlockEnvironmentethereum.paris.vm.BlockEnvironment, ​​transactions: Tuple[Union[LegacyTransaction, Bytes], ...], ​​ommers: Tuple[Header, ...]) -> ethereum.gray_glacier.vm.BlockOutputethereum.paris.vm.BlockOutput:
421
    """
422
    Executes a block.
423
424
    Many of the contents of a block are stored in data structures called
425
    tries. There is a transactions trie which is similar to a ledger of the
426
    transactions stored in the current block. There is also a receipts trie
427
    which stores the results of executing a transaction, like the post state
428
    and gas used. This function creates and executes the block that is to be
429
    added to the chain.
430
431
    Parameters
432
    ----------
433
    block_env :
434
        The block scoped environment.
435
    transactions :
436
        Transactions included in the block.
537
    ommers :
538
        Headers of ancestor blocks which are not direct parents (formerly
539
        uncles.)
437
438
    Returns
439
    -------
440
    block_output :
441
        The block output for the current block.
442
    """
443
    block_output = vm.BlockOutput()
444
445
    for i, tx in enumerate(map(decode_transaction, transactions)):
446
        process_transaction(block_env, block_output, tx, Uint(i))
447
551
    pay_rewards(block_env.state, block_env.number, block_env.coinbase, ommers)
552
448
    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:
559
    """
560
    Validates the ommers mentioned in the block.
561
562
    An ommer block is a block that wasn't canonically added to the
563
    blockchain because it wasn't validated as fast as the canonical block
564
    but was mined at the same time.
565
566
    To be considered valid, the ommers must adhere to the rules defined in
567
    the Ethereum protocol. The maximum amount of ommers is 2 per block and
568
    there cannot be duplicate ommers in a block. Many of the other ommer
569
    constraints are listed in the in-line comments of this function.
570
571
    Parameters
572
    ----------
573
    ommers :
574
        List of ommers mentioned in the current block.
575
    block_header:
576
        The header of current block.
577
    chain :
578
        History and current state.
579
    """
580
    block_hash = keccak256(rlp.encode(block_header))
581
    if keccak256(rlp.encode(ommers)) != block_header.ommers_hash:
582
        raise InvalidBlock
583
584
    if len(ommers) == 0:
585
        # Nothing to validate
586
        return
587
588
    # Check that each ommer satisfies the constraints of a header
589
    for ommer in ommers:
590
        if Uint(1) > ommer.number or ommer.number >= block_header.number:
591
            raise InvalidBlock
592
        validate_header(chain, ommer)
593
    if len(ommers) > 2:
594
        raise InvalidBlock
595
596
    ommers_hashes = [keccak256(rlp.encode(ommer)) for ommer in ommers]
597
    if len(ommers_hashes) != len(set(ommers_hashes)):
598
        raise InvalidBlock
599
600
    recent_canonical_blocks = chain.blocks[-(MAX_OMMER_DEPTH + Uint(1)) :]
601
    recent_canonical_block_hashes = {
602
        keccak256(rlp.encode(block.header))
603
        for block in recent_canonical_blocks
604
    }
605
    recent_ommers_hashes: Set[Hash32] = set()
606
    for block in recent_canonical_blocks:
607
        recent_ommers_hashes = recent_ommers_hashes.union(
608
            {keccak256(rlp.encode(ommer)) for ommer in block.ommers}
609
        )
610
611
    for ommer_index, ommer in enumerate(ommers):
612
        ommer_hash = ommers_hashes[ommer_index]
613
        if ommer_hash == block_hash:
614
            raise InvalidBlock
615
        if ommer_hash in recent_canonical_block_hashes:
616
            raise InvalidBlock
617
        if ommer_hash in recent_ommers_hashes:
618
            raise InvalidBlock
619
620
        # Ommer age with respect to the current block. For example, an age of
621
        # 1 indicates that the ommer is a sibling of previous block.
622
        ommer_age = block_header.number - ommer.number
623
        if Uint(1) > ommer_age or ommer_age > MAX_OMMER_DEPTH:
624
            raise InvalidBlock
625
        if ommer.parent_hash not in recent_canonical_block_hashes:
626
            raise InvalidBlock
627
        if ommer.parent_hash == block_header.parent_hash:
628
            raise InvalidBlock

pay_rewards

Pay rewards to the block miner as well as the ommers miners.

The miner of the canonical block is rewarded with the predetermined block reward, BLOCK_REWARD, plus a variable award based off of the number of ommer blocks that were mined around the same time, and included in the canonical block's header. An ommer block is a block that wasn't added to the canonical blockchain because it wasn't validated as fast as the accepted block but was mined at the same time. Although not all blocks that are mined are added to the canonical chain, miners are still paid a reward for their efforts. This reward is called an ommer reward and is calculated based on the number associated with the ommer block that they mined.

Parameters

state : Current account state. block_number : Position of the block within the chain. coinbase : Address of account which receives block reward and transaction fees. ommers : List of ommers mentioned in the current block.

def pay_rewards(state: State, ​​block_number: Uint, ​​coinbase: Address, ​​ommers: Tuple[Header, ...]) -> None:
637
    """
638
    Pay rewards to the block miner as well as the ommers miners.
639
640
    The miner of the canonical block is rewarded with the predetermined
641
    block reward, ``BLOCK_REWARD``, plus a variable award based off of the
642
    number of ommer blocks that were mined around the same time, and included
643
    in the canonical block's header. An ommer block is a block that wasn't
644
    added to the canonical blockchain because it wasn't validated as fast as
645
    the accepted block but was mined at the same time. Although not all blocks
646
    that are mined are added to the canonical chain, miners are still paid a
647
    reward for their efforts. This reward is called an ommer reward and is
648
    calculated based on the number associated with the ommer block that they
649
    mined.
650
651
    Parameters
652
    ----------
653
    state :
654
        Current account state.
655
    block_number :
656
        Position of the block within the chain.
657
    coinbase :
658
        Address of account which receives block reward and transaction fees.
659
    ommers :
660
        List of ommers mentioned in the current block.
661
    """
662
    ommer_count = U256(len(ommers))
663
    miner_reward = BLOCK_REWARD + (ommer_count * (BLOCK_REWARD // U256(32)))
664
    create_ether(state, coinbase, miner_reward)
665
666
    for ommer in ommers:
667
        # Ommer age with respect to the current block.
668
        ommer_age = U256(block_number - ommer.number)
669
        ommer_miner_reward = ((U256(8) - ommer_age) * BLOCK_REWARD) // U256(8)
670
        create_ether(state, ommer.coinbase, ommer_miner_reward)

process_transaction

Execute a transaction against the provided environment.

This function processes the actions needed to execute a transaction. It decrements the sender's account after calculating the gas fee and refunds them the proper amount after execution. Calling contracts, deploying code, and incrementing nonces are all examples of actions that happen within this function or from a call made within this function.

Accounts that are marked for deletion are processed and destroyed after execution.

Parameters

block_env : Environment for the Ethereum Virtual Machine. block_output : The block output for the current block. tx : Transaction to execute. index: Index of the transaction in the block.

def process_transaction(block_env: ethereum.gray_glacier.vm.BlockEnvironmentethereum.paris.vm.BlockEnvironment, ​​block_output: ethereum.gray_glacier.vm.BlockOutputethereum.paris.vm.BlockOutput, ​​tx: Transaction, ​​index: Uint) -> None:
457
    """
458
    Execute a transaction against the provided environment.
459
460
    This function processes the actions needed to execute a transaction.
461
    It decrements the sender's account after calculating the gas fee and
462
    refunds them the proper amount after execution. Calling contracts,
463
    deploying code, and incrementing nonces are all examples of actions that
464
    happen within this function or from a call made within this function.
465
466
    Accounts that are marked for deletion are processed and destroyed after
467
    execution.
468
469
    Parameters
470
    ----------
471
    block_env :
472
        Environment for the Ethereum Virtual Machine.
473
    block_output :
474
        The block output for the current block.
475
    tx :
476
        Transaction to execute.
477
    index:
478
        Index of the transaction in the block.
479
    """
480
    trie_set(
481
        block_output.transactions_trie,
482
        rlp.encode(index),
483
        encode_transaction(tx),
484
    )
485
486
    intrinsic_gas = validate_transaction(tx)
487
488
    (
489
        sender,
490
        effective_gas_price,
491
    ) = check_transaction(
492
        block_env=block_env,
493
        block_output=block_output,
494
        tx=tx,
495
    )
496
497
    sender_account = get_account(block_env.state, sender)
498
499
    effective_gas_fee = tx.gas * effective_gas_price
500
501
    gas = tx.gas - intrinsic_gas
502
    increment_nonce(block_env.state, sender)
503
504
    sender_balance_after_gas_fee = (
505
        Uint(sender_account.balance) - effective_gas_fee
506
    )
507
    set_account_balance(
508
        block_env.state, sender, U256(sender_balance_after_gas_fee)
509
    )
510
511
    access_list_addresses = set()
512
    access_list_storage_keys = set()
513
    if isinstance(tx, (AccessListTransaction, FeeMarketTransaction)):
514
        for access in tx.access_list:
515
            access_list_addresses.add(access.account)
516
            for slot in access.slots:
517
                access_list_storage_keys.add((access.account, slot))
518
519
    tx_env = vm.TransactionEnvironment(
520
        origin=sender,
521
        gas_price=effective_gas_price,
522
        gas=gas,
523
        access_list_addresses=access_list_addresses,
524
        access_list_storage_keys=access_list_storage_keys,
525
        index_in_block=index,
526
        tx_hash=get_transaction_hash(encode_transaction(tx)),
527
        traces=[],
528
    )
529
530
    message = prepare_message(block_env, tx_env, tx)
531
532
    tx_output = process_message_call(message)
533
534
    tx_gas_used_before_refund = tx.gas - tx_output.gas_left
535
    tx_gas_refund = min(
536
        tx_gas_used_before_refund // Uint(5), Uint(tx_output.refund_counter)
537
    )
538
    tx_gas_used_after_refund = tx_gas_used_before_refund - tx_gas_refund
539
    tx_gas_left = tx.gas - tx_gas_used_after_refund
540
    gas_refund_amount = tx_gas_left * effective_gas_price
541
542
    # For non-1559 transactions effective_gas_price == tx.gas_price
543
    priority_fee_per_gas = effective_gas_price - block_env.base_fee_per_gas
544
    transaction_fee = tx_gas_used_after_refund * priority_fee_per_gas
545
546
    # refund gas
547
    sender_balance_after_refund = get_account(
548
        block_env.state, sender
549
    ).balance + U256(gas_refund_amount)
550
    set_account_balance(block_env.state, sender, sender_balance_after_refund)
551
552
    # transfer miner fees
553
    coinbase_balance_after_mining_fee = get_account(
554
        block_env.state, block_env.coinbase
555
    ).balance + U256(transaction_fee)
556
    if coinbase_balance_after_mining_fee != 0:
557
        set_account_balance(
558
            block_env.state,
559
            block_env.coinbase,
560
            coinbase_balance_after_mining_fee,
561
        )
562
    elif account_exists_and_is_empty(block_env.state, block_env.coinbase):
563
        destroy_account(block_env.state, block_env.coinbase)
564
565
    for address in tx_output.accounts_to_delete:
566
        destroy_account(block_env.state, address)
567
790
    destroy_touched_empty_accounts(block_env.state, tx_output.touched_accounts)
791
568
    block_output.block_gas_used += tx_gas_used_after_refund
569
570
    receipt = make_receipt(
571
        tx, tx_output.error, block_output.block_gas_used, tx_output.logs
572
    )
573
574
    receipt_key = rlp.encode(Uint(index))
575
    block_output.receipt_keys += (receipt_key,)
576
577
    trie_set(
578
        block_output.receipts_trie,
579
        receipt_key,
580
        receipt,
581
    )
582
583
    block_output.block_logs += tx_output.logs

check_gas_limit

Validates the gas limit for a block.

The bounds of the gas limit, max_adjustment_delta, is set as the quotient of the parent block's gas limit and the GAS_LIMIT_ADJUSTMENT_FACTOR. Therefore, if the gas limit that is passed through as a parameter is greater than or equal to the sum of the parent's gas and the adjustment delta then the limit for gas is too high and fails this function's check. Similarly, if the limit is less than or equal to the difference of the parent's gas and the adjustment delta or the predefined GAS_LIMIT_MINIMUM then this function's check fails because the gas limit doesn't allow for a sufficient or reasonable amount of gas to be used on a block.

Parameters

gas_limit : Gas limit to validate.

parent_gas_limit : Gas limit of the parent block.

Returns

check : bool True if gas limit constraints are satisfied, False otherwise.

def check_gas_limit(gas_limit: Uint, ​​parent_gas_limit: Uint) -> bool:
587
    """
588
    Validates the gas limit for a block.
589
590
    The bounds of the gas limit, ``max_adjustment_delta``, is set as the
591
    quotient of the parent block's gas limit and the
592
    ``GAS_LIMIT_ADJUSTMENT_FACTOR``. Therefore, if the gas limit that is
593
    passed through as a parameter is greater than or equal to the *sum* of
594
    the parent's gas and the adjustment delta then the limit for gas is too
595
    high and fails this function's check. Similarly, if the limit is less
596
    than or equal to the *difference* of the parent's gas and the adjustment
597
    delta *or* the predefined ``GAS_LIMIT_MINIMUM`` then this function's
598
    check fails because the gas limit doesn't allow for a sufficient or
599
    reasonable amount of gas to be used on a block.
600
601
    Parameters
602
    ----------
603
    gas_limit :
604
        Gas limit to validate.
605
606
    parent_gas_limit :
607
        Gas limit of the parent block.
608
609
    Returns
610
    -------
611
    check : `bool`
612
        True if gas limit constraints are satisfied, False otherwise.
613
    """
614
    max_adjustment_delta = parent_gas_limit // GAS_LIMIT_ADJUSTMENT_FACTOR
615
    if gas_limit >= parent_gas_limit + max_adjustment_delta:
616
        return False
617
    if gas_limit <= parent_gas_limit - max_adjustment_delta:
618
        return False
619
    if gas_limit < GAS_LIMIT_MINIMUM:
620
        return False
621
622
    return True

calculate_block_difficulty

Computes difficulty of a block using its header and parent header.

The difficulty is determined by the time the block was created after its parent. The offset is calculated using the parent block's difficulty, parent_difficulty, and the timestamp between blocks. This offset is then added to the parent difficulty and is stored as the difficulty variable. If the time between the block and its parent is too short, the offset will result in a positive number thus making the sum of parent_difficulty and offset to be a greater value in order to avoid mass forking. But, if the time is long enough, then the offset results in a negative value making the block less difficult than its parent.

The base standard for a block's difficulty is the predefined value set for the genesis block since it has no parent. So, a block can't be less difficult than the genesis block, therefore each block's difficulty is set to the maximum value between the calculated difficulty and the GENESIS_DIFFICULTY.

Parameters

block_number : Block number of the block. block_timestamp : Timestamp of the block. parent_timestamp : Timestamp of the parent block. parent_difficulty : difficulty of the parent block. parent_has_ommers: does the parent have ommers.

Returns

difficulty : ethereum.base_types.Uint Computed difficulty for a block.

def calculate_block_difficulty(block_number: Uint, ​​block_timestamp: U256, ​​parent_timestamp: U256, ​​parent_difficulty: Uint, ​​parent_has_ommers: bool) -> Uint:
856
    """
857
    Computes difficulty of a block using its header and parent header.
858
859
    The difficulty is determined by the time the block was created after its
860
    parent. The ``offset`` is calculated using the parent block's difficulty,
861
    ``parent_difficulty``, and the timestamp between blocks. This offset is
862
    then added to the parent difficulty and is stored as the ``difficulty``
863
    variable. If the time between the block and its parent is too short, the
864
    offset will result in a positive number thus making the sum of
865
    ``parent_difficulty`` and ``offset`` to be a greater value in order to
866
    avoid mass forking. But, if the time is long enough, then the offset
867
    results in a negative value making the block less difficult than
868
    its parent.
869
870
    The base standard for a block's difficulty is the predefined value
871
    set for the genesis block since it has no parent. So, a block
872
    can't be less difficult than the genesis block, therefore each block's
873
    difficulty is set to the maximum value between the calculated
874
    difficulty and the ``GENESIS_DIFFICULTY``.
875
876
    Parameters
877
    ----------
878
    block_number :
879
        Block number of the block.
880
    block_timestamp :
881
        Timestamp of the block.
882
    parent_timestamp :
883
        Timestamp of the parent block.
884
    parent_difficulty :
885
        difficulty of the parent block.
886
    parent_has_ommers:
887
        does the parent have ommers.
888
889
    Returns
890
    -------
891
    difficulty : `ethereum.base_types.Uint`
892
        Computed difficulty for a block.
893
    """
894
    offset = (
895
        int(parent_difficulty)
896
        // 2048
897
        * max(
898
            (2 if parent_has_ommers else 1)
899
            - int(block_timestamp - parent_timestamp) // 9,
900
            -99,
901
        )
902
    )
903
    difficulty = int(parent_difficulty) + offset
904
    # Historical Note: The difficulty bomb was not present in Ethereum at the
905
    # start of Frontier, but was added shortly after launch. However since the
906
    # bomb has no effect prior to block 200000 we pretend it existed from
907
    # genesis.
908
    # See https://github.com/ethereum/go-ethereum/pull/1588
909
    num_bomb_periods = ((int(block_number) - BOMB_DELAY_BLOCKS) // 100000) - 2
910
    if num_bomb_periods >= 0:
911
        difficulty += 2**num_bomb_periods
912
913
    # Some clients raise the difficulty to `MINIMUM_DIFFICULTY` prior to adding
914
    # the bomb. This bug does not matter because the difficulty is always much
915
    # greater than `MINIMUM_DIFFICULTY` on Mainnet.
916
    return Uint(max(difficulty, int(MINIMUM_DIFFICULTY)))