ethereum.forks.bpo5.vm.interpreterethereum.forks.amsterdam.vm.interpreter
Ethereum Virtual Machine (EVM) Interpreter.
.. contents:: Table of Contents :backlinks: none :local:
Introduction
A straightforward interpreter that executes EVM code.
STACK_DEPTH_LIMIT¶
| 70 | STACK_DEPTH_LIMIT = Uint(1024) |
|---|
MAX_CODE_SIZE¶
| 65 | MAX_CODE_SIZE = 0x6000 |
|---|---|
| 71 | MAX_CODE_SIZE = 0x8000 |
MAX_INIT_CODE_SIZE¶
| 72 | MAX_INIT_CODE_SIZE = 2 * MAX_CODE_SIZE |
|---|
MessageCallOutput ¶
Output of a particular message call.
Contains the following:
1. `gas_left`: remaining gas after execution.
2. `refund_counter`: gas to refund after execution.
3. `logs`: list of `Log` generated during execution.
4. `accounts_to_delete`: Contracts which have self-destructed.
5. `error`: The error from the execution if any.
6. `return_data`: The output of the execution.
1. `gas_left`: remaining gas after execution.
2. `refund_counter`: gas to refund after execution.
3. `logs`: list of `Log` generated during execution.
4. `accounts_to_delete`: Contracts which have self-destructed.
5. `error`: The error from the execution if any.
6. `return_data`: The output of the execution.
7. `regular_gas_used`: Regular gas used during execution.
8. `state_gas_used`: State gas used during execution.
9. `state_refund`: State gas refunded by `set_delegation` for
authorities that already existed in state. Subtracted from
`tx_state_gas` in block accounting so `block.gas_used`
matches the receipt `cumulative_gas_used`.
| 75 | @final |
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| 76 | @dataclass |
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class MessageCallOutput:
gas_left¶
| 97 | gas_left: Uint |
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refund_counter¶
| 98 | refund_counter: U256 |
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logs¶
| 99 | logs: Tuple[Log, ...] |
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accounts_to_delete¶
| 100 | accounts_to_delete: Set[Address] |
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error¶
| 101 | error: Optional[EthereumException] |
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return_data¶
| 102 | return_data: Bytes |
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state_gas_left¶
| 103 | state_gas_left: Uint |
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regular_gas_used¶
| 104 | regular_gas_used: Uint |
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state_gas_used¶
| 105 | state_gas_used: int |
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state_refund¶
| 106 | state_refund: Uint |
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process_message_call ¶
If message.target is empty then it creates a smart contract
else it executes a call from the message.caller to the message.target.
Parameters
message : Transaction specific items.
Returns
output : MessageCallOutput
Output of the message call
def process_message_call(message: Message) -> MessageCallOutput:
| 110 | <snip> |
|---|---|
| 125 | tx_state = message.tx_env.state |
| 126 | refund_counter = U256(0) |
| 127 | state_refund = Uint(0) |
| 128 | if message.target == Bytes0(b""): |
| 129 | is_collision = account_has_code_or_nonce( |
| 130 | tx_state, message.current_target |
| 131 | ) or account_has_storage(tx_state, message.current_target) |
| 132 | if is_collision: |
| 133 | return MessageCallOutput( |
| 134 | gas_left=Uint(0), |
| 135 | refund_counter=U256(0), |
| 136 | logs=tuple(), |
| 137 | accounts_to_delete=set(), |
| 138 | error=AddressCollision(), |
| 139 | return_data=Bytes(b""), |
| 140 | state_gas_left=message.state_gas_reservoir, |
| 141 | regular_gas_used=message.gas, |
| 142 | state_gas_used=0, |
| 143 | state_refund=Uint(0), |
| 144 | ) |
| 145 | else: |
| 146 | evm = process_create_message(message) |
| 147 | else: |
| 148 | if message.tx_env.authorizations != (): |
| 128 | refund_counter += set_delegation(message) |
| 149 | state_refund += set_delegation(message) |
| 150 | |
| 151 | delegated_address = get_delegated_code_address(message.code) |
| 152 | if delegated_address is not None: |
| 153 | message.disable_precompiles = True |
| 154 | message.accessed_addresses.add(delegated_address) |
| 155 | message.code = get_code( |
| 156 | tx_state, |
| 157 | get_account(tx_state, delegated_address).code_hash, |
| 158 | ) |
| 159 | message.code_address = delegated_address |
| 160 | |
| 161 | evm = process_message(message) |
| 162 | |
| 163 | if evm.error: |
| 164 | logs: Tuple[Log, ...] = () |
| 165 | accounts_to_delete = set() |
| 166 | else: |
| 167 | logs = evm.logs |
| 168 | accounts_to_delete = evm.accounts_to_delete |
| 169 | refund_counter += U256(evm.refund_counter) |
| 170 | |
| 171 | tx_end = TransactionEnd( |
| 172 | int(message.gas) - int(evm.gas_left), evm.output, evm.error |
| 173 | ) |
| 174 | evm_trace(evm, tx_end) |
| 175 | |
| 176 | return MessageCallOutput( |
| 177 | gas_left=evm.gas_left, |
| 178 | refund_counter=refund_counter, |
| 179 | logs=logs, |
| 180 | accounts_to_delete=accounts_to_delete, |
| 181 | error=evm.error, |
| 182 | return_data=evm.output, |
| 183 | state_gas_left=evm.state_gas_left, |
| 184 | regular_gas_used=evm.regular_gas_used, |
| 185 | state_gas_used=evm.state_gas_used, |
| 186 | state_refund=state_refund, |
| 187 | ) |
process_create_message ¶
Executes a call to create a smart contract.
Parameters
message : Transaction specific items.
Returns
evm: :py:class:
Items containing execution specific objects.~ethereum.forks.bpo5.vm.Evm~ethereum.forks.amsterdam.vm.Evm
def process_create_message(message: Message) -> Evm:
| 191 | <snip> |
|---|---|
| 205 | tx_state = message.tx_env.state |
| 206 | # take snapshot of state before processing the message |
| 207 | snapshot = copy_tx_state(tx_state) |
| 208 | |
| 209 | # If the address where the account is being created has storage, it is |
| 210 | # destroyed. This can only happen in the following highly unlikely |
| 211 | # circumstances: |
| 212 | # * The address created by a `CREATE` call collides with a subsequent |
| 213 | # `CREATE` or `CREATE2` call. |
| 214 | # * The first `CREATE` happened before Spurious Dragon and left empty |
| 215 | # code. |
| 216 | destroy_storage(tx_state, message.current_target) |
| 217 | |
| 218 | # In the previously mentioned edge case the preexisting storage is ignored |
| 219 | # for gas refund purposes. In order to do this we must track created |
| 220 | # accounts. This tracking is also needed to respect the constraints |
| 221 | # added to SELFDESTRUCT by EIP-6780. |
| 222 | mark_account_created(tx_state, message.current_target) |
| 223 | |
| 224 | increment_nonce(tx_state, message.current_target) |
| 225 | |
| 226 | evm = process_message(message) |
| 227 | if not evm.error: |
| 228 | contract_code = evm.output |
| 203 | contract_code_gas = ( |
| 204 | ulen(contract_code) * GasCosts.CODE_DEPOSIT_PER_BYTE |
| 205 | ) |
| 229 | try: |
| 230 | if len(contract_code) > 0: |
| 231 | if contract_code[0] == 0xEF: |
| 232 | raise InvalidContractPrefix |
| 210 | charge_gas(evm, contract_code_gas) |
| 233 | if len(contract_code) > MAX_CODE_SIZE: |
| 212 | raise OutOfGasError |
| 234 | raise OutOfGasError |
| 235 | # Hash cost for computing keccak256 of deployed bytecode |
| 236 | code_hash_gas = ( |
| 237 | GasCosts.OPCODE_KECCAK256_PER_WORD |
| 238 | * ceil32(ulen(contract_code)) |
| 239 | // Uint(32) |
| 240 | ) |
| 241 | charge_gas(evm, code_hash_gas) |
| 242 | code_deposit_state_gas = ( |
| 243 | ulen(contract_code) * StateGasCosts.COST_PER_STATE_BYTE |
| 244 | ) |
| 245 | charge_state_gas(evm, code_deposit_state_gas) |
| 246 | except ExceptionalHalt as error: |
| 247 | restore_tx_state(tx_state, snapshot) |
| 248 | evm.regular_gas_used += evm.gas_left |
| 249 | evm.gas_left = Uint(0) |
| 250 | evm.output = b"" |
| 251 | evm.error = error |
| 252 | else: |
| 253 | set_code(tx_state, message.current_target, contract_code) |
| 254 | else: |
| 255 | restore_tx_state(tx_state, snapshot) |
| 256 | return evm |
process_message ¶
Move ether and execute the relevant code.
Parameters
message : Transaction specific items.
Returns
evm: :py:class:
Items containing execution specific objects~ethereum.forks.bpo5.vm.Evm~ethereum.forks.amsterdam.vm.Evm
def process_message(message: Message) -> Evm:
| 260 | <snip> |
|---|---|
| 274 | tx_state = message.tx_env.state |
| 275 | if message.depth > STACK_DEPTH_LIMIT: |
| 276 | raise StackDepthLimitError("Stack depth limit reached") |
| 277 | |
| 278 | code = message.code |
| 279 | valid_jump_destinations = get_valid_jump_destinations(code) |
| 280 | evm = Evm( |
| 281 | pc=Uint(0), |
| 282 | stack=[], |
| 283 | memory=bytearray(), |
| 284 | code=code, |
| 285 | gas_left=message.gas, |
| 286 | state_gas_left=message.state_gas_reservoir, |
| 287 | valid_jump_destinations=valid_jump_destinations, |
| 288 | logs=(), |
| 289 | refund_counter=0, |
| 290 | running=True, |
| 291 | message=message, |
| 292 | output=b"", |
| 293 | accounts_to_delete=set(), |
| 294 | return_data=b"", |
| 295 | error=None, |
| 296 | accessed_addresses=message.accessed_addresses, |
| 297 | accessed_storage_keys=message.accessed_storage_keys, |
| 298 | ) |
| 299 | |
| 265 | # take snapshot of state before processing the message |
| 266 | snapshot = copy_tx_state(tx_state) |
| 300 | snapshot = copy_tx_state(tx_state) |
| 301 | |
| 302 | if message.should_transfer_value and message.value != 0: |
| 303 | move_ether( |
| 304 | tx_state, |
| 305 | message.caller, |
| 306 | message.current_target, |
| 307 | message.value, |
| 274 | ) |
| 308 | ) |
| 309 | if message.caller != message.current_target: |
| 310 | emit_transfer_log( |
| 311 | evm, message.caller, message.current_target, message.value |
| 312 | ) |
| 313 | |
| 276 | try: |
| 314 | # Execute message code and handle errors |
| 315 | try: |
| 316 | if evm.message.code_address in PRE_COMPILED_CONTRACTS: |
| 317 | if not message.disable_precompiles: |
| 318 | evm_trace(evm, PrecompileStart(evm.message.code_address)) |
| 319 | PRE_COMPILED_CONTRACTS[evm.message.code_address](evm) |
| 320 | evm_trace(evm, PrecompileEnd()) |
| 321 | else: |
| 322 | while evm.running and evm.pc < ulen(evm.code): |
| 323 | try: |
| 324 | op = Ops(evm.code[evm.pc]) |
| 325 | except ValueError as e: |
| 326 | raise InvalidOpcode(evm.code[evm.pc]) from e |
| 327 | |
| 328 | evm_trace(evm, OpStart(op)) |
| 329 | op_implementation[op](evm) |
| 330 | evm_trace(evm, OpEnd()) |
| 331 | |
| 332 | evm_trace(evm, EvmStop(Ops.STOP)) |
| 333 | |
| 334 | except ExceptionalHalt as error: |
| 335 | evm_trace(evm, OpException(error)) |
| 336 | evm.regular_gas_used += evm.gas_left |
| 337 | evm.gas_left = Uint(0) |
| 338 | evm.output = b"" |
| 339 | evm.error = error |
| 340 | except Revert as error: |
| 341 | evm_trace(evm, OpException(error)) |
| 342 | evm.error = error |
| 343 | |
| 344 | if evm.error: |
| 345 | restore_tx_state(tx_state, snapshot) |
| 346 | return evm |