ethereum.forks.dao_fork.vm.instructions.system
Ethereum Virtual Machine (EVM) System Instructions.
.. contents:: Table of Contents :backlinks: none :local:
Introduction
Implementations of the EVM system related instructions.
create ¶
Creates a new account with associated code.
Parameters
evm : The current EVM frame.
def create(evm: Evm) -> None:
| 45 | """ |
|---|---|
| 46 | Creates a new account with associated code. |
| 47 | |
| 48 | Parameters |
| 49 | ---------- |
| 50 | evm : |
| 51 | The current EVM frame. |
| 52 | |
| 53 | """ |
| 54 | # This import causes a circular import error |
| 55 | # if it's not moved inside this method |
| 56 | from ...vm.interpreter import STACK_DEPTH_LIMIT, process_create_message |
| 57 | |
| 58 | # STACK |
| 59 | endowment = pop(evm.stack) |
| 60 | memory_start_position = pop(evm.stack) |
| 61 | memory_size = pop(evm.stack) |
| 62 | |
| 63 | # GAS |
| 64 | extend_memory = calculate_gas_extend_memory( |
| 65 | evm.memory, [(memory_start_position, memory_size)] |
| 66 | ) |
| 67 | |
| 68 | charge_gas(evm, GasCosts.OPCODE_CREATE_BASE + extend_memory.cost) |
| 69 | |
| 70 | create_message_gas = evm.gas_left |
| 71 | evm.gas_left = Uint(0) |
| 72 | |
| 73 | # OPERATION |
| 74 | evm.memory += b"\x00" * extend_memory.expand_by |
| 75 | sender_address = evm.message.current_target |
| 76 | sender = get_account(evm.message.block_env.state, sender_address) |
| 77 | |
| 78 | contract_address = compute_contract_address( |
| 79 | evm.message.current_target, |
| 80 | get_account( |
| 81 | evm.message.block_env.state, evm.message.current_target |
| 82 | ).nonce, |
| 83 | ) |
| 84 | |
| 85 | if ( |
| 86 | sender.balance < endowment |
| 87 | or sender.nonce == Uint(2**64 - 1) |
| 88 | or evm.message.depth + Uint(1) > STACK_DEPTH_LIMIT |
| 89 | ): |
| 90 | push(evm.stack, U256(0)) |
| 91 | evm.gas_left += create_message_gas |
| 92 | elif account_has_code_or_nonce( |
| 93 | evm.message.block_env.state, contract_address |
| 94 | ) or account_has_storage(evm.message.block_env.state, contract_address): |
| 95 | increment_nonce( |
| 96 | evm.message.block_env.state, evm.message.current_target |
| 97 | ) |
| 98 | push(evm.stack, U256(0)) |
| 99 | else: |
| 100 | call_data = memory_read_bytes( |
| 101 | evm.memory, memory_start_position, memory_size |
| 102 | ) |
| 103 | |
| 104 | increment_nonce( |
| 105 | evm.message.block_env.state, evm.message.current_target |
| 106 | ) |
| 107 | |
| 108 | child_message = Message( |
| 109 | block_env=evm.message.block_env, |
| 110 | tx_env=evm.message.tx_env, |
| 111 | caller=evm.message.current_target, |
| 112 | target=Bytes0(), |
| 113 | gas=create_message_gas, |
| 114 | value=endowment, |
| 115 | data=b"", |
| 116 | code=call_data, |
| 117 | current_target=contract_address, |
| 118 | depth=evm.message.depth + Uint(1), |
| 119 | code_address=None, |
| 120 | should_transfer_value=True, |
| 121 | parent_evm=evm, |
| 122 | ) |
| 123 | child_evm = process_create_message(child_message) |
| 124 | |
| 125 | if child_evm.error: |
| 126 | incorporate_child_on_error(evm, child_evm) |
| 127 | push(evm.stack, U256(0)) |
| 128 | else: |
| 129 | incorporate_child_on_success(evm, child_evm) |
| 130 | push( |
| 131 | evm.stack, U256.from_be_bytes(child_evm.message.current_target) |
| 132 | ) |
| 133 | |
| 134 | # PROGRAM COUNTER |
| 135 | evm.pc += Uint(1) |
return_ ¶
Halts execution returning output data.
Parameters
evm : The current EVM frame.
def return_(evm: Evm) -> None:
| 139 | """ |
|---|---|
| 140 | Halts execution returning output data. |
| 141 | |
| 142 | Parameters |
| 143 | ---------- |
| 144 | evm : |
| 145 | The current EVM frame. |
| 146 | |
| 147 | """ |
| 148 | # STACK |
| 149 | memory_start_position = pop(evm.stack) |
| 150 | memory_size = pop(evm.stack) |
| 151 | |
| 152 | # GAS |
| 153 | extend_memory = calculate_gas_extend_memory( |
| 154 | evm.memory, [(memory_start_position, memory_size)] |
| 155 | ) |
| 156 | |
| 157 | charge_gas(evm, GasCosts.ZERO + extend_memory.cost) |
| 158 | |
| 159 | # OPERATION |
| 160 | evm.memory += b"\x00" * extend_memory.expand_by |
| 161 | evm.output = memory_read_bytes( |
| 162 | evm.memory, memory_start_position, memory_size |
| 163 | ) |
| 164 | |
| 165 | evm.running = False |
| 166 | |
| 167 | # PROGRAM COUNTER |
| 168 | pass |
generic_call ¶
Perform the core logic of the CALL* family of opcodes.
def generic_call(evm: Evm, gas: Uint, value: U256, caller: Address, to: Address, code_address: Address, should_transfer_value: bool, memory_input_start_position: U256, memory_input_size: U256, memory_output_start_position: U256, memory_output_size: U256) -> None:
| 184 | """ |
|---|---|
| 185 | Perform the core logic of the `CALL*` family of opcodes. |
| 186 | """ |
| 187 | from ...vm.interpreter import STACK_DEPTH_LIMIT, process_message |
| 188 | |
| 189 | if evm.message.depth + Uint(1) > STACK_DEPTH_LIMIT: |
| 190 | evm.gas_left += gas |
| 191 | push(evm.stack, U256(0)) |
| 192 | return |
| 193 | |
| 194 | call_data = memory_read_bytes( |
| 195 | evm.memory, memory_input_start_position, memory_input_size |
| 196 | ) |
| 197 | account_to_call = get_account(evm.message.block_env.state, code_address) |
| 198 | code = get_code(evm.message.block_env.state, account_to_call.code_hash) |
| 199 | child_message = Message( |
| 200 | block_env=evm.message.block_env, |
| 201 | tx_env=evm.message.tx_env, |
| 202 | caller=caller, |
| 203 | target=to, |
| 204 | gas=gas, |
| 205 | value=value, |
| 206 | data=call_data, |
| 207 | code=code, |
| 208 | current_target=to, |
| 209 | depth=evm.message.depth + Uint(1), |
| 210 | code_address=code_address, |
| 211 | should_transfer_value=should_transfer_value, |
| 212 | parent_evm=evm, |
| 213 | ) |
| 214 | child_evm = process_message(child_message) |
| 215 | |
| 216 | if child_evm.error: |
| 217 | incorporate_child_on_error(evm, child_evm) |
| 218 | push(evm.stack, U256(0)) |
| 219 | else: |
| 220 | incorporate_child_on_success(evm, child_evm) |
| 221 | push(evm.stack, U256(1)) |
| 222 | |
| 223 | actual_output_size = min(memory_output_size, U256(len(child_evm.output))) |
| 224 | memory_write( |
| 225 | evm.memory, |
| 226 | memory_output_start_position, |
| 227 | child_evm.output[:actual_output_size], |
| 228 | ) |
call ¶
Message-call into an account.
Parameters
evm : The current EVM frame.
def call(evm: Evm) -> None:
| 232 | """ |
|---|---|
| 233 | Message-call into an account. |
| 234 | |
| 235 | Parameters |
| 236 | ---------- |
| 237 | evm : |
| 238 | The current EVM frame. |
| 239 | |
| 240 | """ |
| 241 | # STACK |
| 242 | gas = Uint(pop(evm.stack)) |
| 243 | to = to_address_masked(pop(evm.stack)) |
| 244 | value = pop(evm.stack) |
| 245 | memory_input_start_position = pop(evm.stack) |
| 246 | memory_input_size = pop(evm.stack) |
| 247 | memory_output_start_position = pop(evm.stack) |
| 248 | memory_output_size = pop(evm.stack) |
| 249 | |
| 250 | # GAS |
| 251 | extend_memory = calculate_gas_extend_memory( |
| 252 | evm.memory, |
| 253 | [ |
| 254 | (memory_input_start_position, memory_input_size), |
| 255 | (memory_output_start_position, memory_output_size), |
| 256 | ], |
| 257 | ) |
| 258 | |
| 259 | code_address = to |
| 260 | |
| 261 | message_call_gas = calculate_message_call_gas( |
| 262 | evm.message.block_env.state, gas, to, value |
| 263 | ) |
| 264 | charge_gas(evm, message_call_gas.cost + extend_memory.cost) |
| 265 | |
| 266 | # OPERATION |
| 267 | evm.memory += b"\x00" * extend_memory.expand_by |
| 268 | sender_balance = get_account( |
| 269 | evm.message.block_env.state, evm.message.current_target |
| 270 | ).balance |
| 271 | if sender_balance < value: |
| 272 | push(evm.stack, U256(0)) |
| 273 | evm.gas_left += message_call_gas.sub_call |
| 274 | else: |
| 275 | generic_call( |
| 276 | evm, |
| 277 | message_call_gas.sub_call, |
| 278 | value, |
| 279 | evm.message.current_target, |
| 280 | to, |
| 281 | code_address, |
| 282 | True, |
| 283 | memory_input_start_position, |
| 284 | memory_input_size, |
| 285 | memory_output_start_position, |
| 286 | memory_output_size, |
| 287 | ) |
| 288 | |
| 289 | # PROGRAM COUNTER |
| 290 | evm.pc += Uint(1) |
callcode ¶
Message-call into this account with alternative account’s code.
Parameters
evm : The current EVM frame.
def callcode(evm: Evm) -> None:
| 294 | """ |
|---|---|
| 295 | Message-call into this account with alternative account’s code. |
| 296 | |
| 297 | Parameters |
| 298 | ---------- |
| 299 | evm : |
| 300 | The current EVM frame. |
| 301 | |
| 302 | """ |
| 303 | # STACK |
| 304 | gas = Uint(pop(evm.stack)) |
| 305 | code_address = to_address_masked(pop(evm.stack)) |
| 306 | value = pop(evm.stack) |
| 307 | memory_input_start_position = pop(evm.stack) |
| 308 | memory_input_size = pop(evm.stack) |
| 309 | memory_output_start_position = pop(evm.stack) |
| 310 | memory_output_size = pop(evm.stack) |
| 311 | |
| 312 | # GAS |
| 313 | to = evm.message.current_target |
| 314 | |
| 315 | extend_memory = calculate_gas_extend_memory( |
| 316 | evm.memory, |
| 317 | [ |
| 318 | (memory_input_start_position, memory_input_size), |
| 319 | (memory_output_start_position, memory_output_size), |
| 320 | ], |
| 321 | ) |
| 322 | message_call_gas = calculate_message_call_gas( |
| 323 | evm.message.block_env.state, gas, to, value |
| 324 | ) |
| 325 | charge_gas(evm, message_call_gas.cost + extend_memory.cost) |
| 326 | |
| 327 | # OPERATION |
| 328 | evm.memory += b"\x00" * extend_memory.expand_by |
| 329 | sender_balance = get_account( |
| 330 | evm.message.block_env.state, evm.message.current_target |
| 331 | ).balance |
| 332 | if sender_balance < value: |
| 333 | push(evm.stack, U256(0)) |
| 334 | evm.gas_left += message_call_gas.sub_call |
| 335 | else: |
| 336 | generic_call( |
| 337 | evm, |
| 338 | message_call_gas.sub_call, |
| 339 | value, |
| 340 | evm.message.current_target, |
| 341 | to, |
| 342 | code_address, |
| 343 | True, |
| 344 | memory_input_start_position, |
| 345 | memory_input_size, |
| 346 | memory_output_start_position, |
| 347 | memory_output_size, |
| 348 | ) |
| 349 | |
| 350 | # PROGRAM COUNTER |
| 351 | evm.pc += Uint(1) |
selfdestruct ¶
Halt execution and register account for later deletion.
Parameters
evm : The current EVM frame.
def selfdestruct(evm: Evm) -> None:
| 355 | """ |
|---|---|
| 356 | Halt execution and register account for later deletion. |
| 357 | |
| 358 | Parameters |
| 359 | ---------- |
| 360 | evm : |
| 361 | The current EVM frame. |
| 362 | |
| 363 | """ |
| 364 | # STACK |
| 365 | beneficiary = to_address_masked(pop(evm.stack)) |
| 366 | |
| 367 | # GAS |
| 368 | gas_cost = GasCosts.ZERO |
| 369 | |
| 370 | originator = evm.message.current_target |
| 371 | |
| 372 | refunded_accounts = evm.accounts_to_delete |
| 373 | parent_evm = evm.message.parent_evm |
| 374 | while parent_evm is not None: |
| 375 | refunded_accounts.update(parent_evm.accounts_to_delete) |
| 376 | parent_evm = parent_evm.message.parent_evm |
| 377 | |
| 378 | if originator not in refunded_accounts: |
| 379 | evm.refund_counter += int(GasCosts.REFUND_SELF_DESTRUCT) |
| 380 | |
| 381 | charge_gas(evm, gas_cost) |
| 382 | |
| 383 | # OPERATION |
| 384 | beneficiary_balance = get_account( |
| 385 | evm.message.block_env.state, beneficiary |
| 386 | ).balance |
| 387 | originator_balance = get_account( |
| 388 | evm.message.block_env.state, originator |
| 389 | ).balance |
| 390 | |
| 391 | # First Transfer to beneficiary |
| 392 | set_account_balance( |
| 393 | evm.message.block_env.state, |
| 394 | beneficiary, |
| 395 | beneficiary_balance + originator_balance, |
| 396 | ) |
| 397 | # Next, Zero the balance of the address being deleted (must come after |
| 398 | # sending to beneficiary in case the contract named itself as the |
| 399 | # beneficiary). |
| 400 | set_account_balance(evm.message.block_env.state, originator, U256(0)) |
| 401 | |
| 402 | # register account for deletion |
| 403 | evm.accounts_to_delete.add(originator) |
| 404 | |
| 405 | # HALT the execution |
| 406 | evm.running = False |
| 407 | |
| 408 | # PROGRAM COUNTER |
| 409 | pass |
delegatecall ¶
Message-call into an account.
Parameters
evm : The current EVM frame.
def delegatecall(evm: Evm) -> None:
| 413 | """ |
|---|---|
| 414 | Message-call into an account. |
| 415 | |
| 416 | Parameters |
| 417 | ---------- |
| 418 | evm : |
| 419 | The current EVM frame. |
| 420 | |
| 421 | """ |
| 422 | # STACK |
| 423 | gas = Uint(pop(evm.stack)) |
| 424 | code_address = to_address_masked(pop(evm.stack)) |
| 425 | memory_input_start_position = pop(evm.stack) |
| 426 | memory_input_size = pop(evm.stack) |
| 427 | memory_output_start_position = pop(evm.stack) |
| 428 | memory_output_size = pop(evm.stack) |
| 429 | |
| 430 | # GAS |
| 431 | extend_memory = calculate_gas_extend_memory( |
| 432 | evm.memory, |
| 433 | [ |
| 434 | (memory_input_start_position, memory_input_size), |
| 435 | (memory_output_start_position, memory_output_size), |
| 436 | ], |
| 437 | ) |
| 438 | charge_gas(evm, GasCosts.OPCODE_CALL_BASE + gas + extend_memory.cost) |
| 439 | |
| 440 | # OPERATION |
| 441 | evm.memory += b"\x00" * extend_memory.expand_by |
| 442 | generic_call( |
| 443 | evm, |
| 444 | gas, |
| 445 | evm.message.value, |
| 446 | evm.message.caller, |
| 447 | evm.message.current_target, |
| 448 | code_address, |
| 449 | False, |
| 450 | memory_input_start_position, |
| 451 | memory_input_size, |
| 452 | memory_output_start_position, |
| 453 | memory_output_size, |
| 454 | ) |
| 455 | |
| 456 | # PROGRAM COUNTER |
| 457 | evm.pc += Uint(1) |