ethereum.frontier.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:
44 | """ |
---|---|
45 | Creates a new account with associated code. |
46 |
|
47 | Parameters |
48 | ---------- |
49 | evm : |
50 | The current EVM frame. |
51 | """ |
52 | # This import causes a circular import error |
53 | # if it's not moved inside this method |
54 | from ...vm.interpreter import STACK_DEPTH_LIMIT, process_create_message |
55 | |
56 | # STACK |
57 | endowment = pop(evm.stack) |
58 | memory_start_position = pop(evm.stack) |
59 | memory_size = pop(evm.stack) |
60 | |
61 | # GAS |
62 | extend_memory = calculate_gas_extend_memory( |
63 | evm.memory, [(memory_start_position, memory_size)] |
64 | ) |
65 | |
66 | charge_gas(evm, GAS_CREATE + extend_memory.cost) |
67 | |
68 | create_message_gas = evm.gas_left |
69 | evm.gas_left = Uint(0) |
70 | |
71 | # OPERATION |
72 | evm.memory += b"\x00" * extend_memory.expand_by |
73 | sender_address = evm.message.current_target |
74 | sender = get_account(evm.env.state, sender_address) |
75 | |
76 | contract_address = compute_contract_address( |
77 | evm.message.current_target, |
78 | get_account(evm.env.state, evm.message.current_target).nonce, |
79 | ) |
80 | |
81 | if ( |
82 | sender.balance < endowment |
83 | or sender.nonce == Uint(2**64 - 1) |
84 | or evm.message.depth + Uint(1) > STACK_DEPTH_LIMIT |
85 | ): |
86 | push(evm.stack, U256(0)) |
87 | evm.gas_left += create_message_gas |
88 | elif account_has_code_or_nonce(evm.env.state, contract_address): |
89 | increment_nonce(evm.env.state, evm.message.current_target) |
90 | push(evm.stack, U256(0)) |
91 | else: |
92 | call_data = memory_read_bytes( |
93 | evm.memory, memory_start_position, memory_size |
94 | ) |
95 |
|
96 | increment_nonce(evm.env.state, evm.message.current_target) |
97 |
|
98 | child_message = Message( |
99 | caller=evm.message.current_target, |
100 | target=Bytes0(), |
101 | gas=create_message_gas, |
102 | value=endowment, |
103 | data=b"", |
104 | code=call_data, |
105 | current_target=contract_address, |
106 | depth=evm.message.depth + Uint(1), |
107 | code_address=None, |
108 | parent_evm=evm, |
109 | ) |
110 | child_evm = process_create_message(child_message, evm.env) |
111 |
|
112 | if child_evm.error: |
113 | incorporate_child_on_error(evm, child_evm) |
114 | push(evm.stack, U256(0)) |
115 | else: |
116 | incorporate_child_on_success(evm, child_evm) |
117 | push( |
118 | evm.stack, U256.from_be_bytes(child_evm.message.current_target) |
119 | ) |
120 | |
121 | # PROGRAM COUNTER |
122 | evm.pc += Uint(1) |
return_
Halts execution returning output data.
Parameters
evm : The current EVM frame.
def return_(evm: Evm) -> None:
126 | """ |
---|---|
127 | Halts execution returning output data. |
128 |
|
129 | Parameters |
130 | ---------- |
131 | evm : |
132 | The current EVM frame. |
133 | """ |
134 | # STACK |
135 | memory_start_position = pop(evm.stack) |
136 | memory_size = pop(evm.stack) |
137 | |
138 | # GAS |
139 | extend_memory = calculate_gas_extend_memory( |
140 | evm.memory, [(memory_start_position, memory_size)] |
141 | ) |
142 | |
143 | charge_gas(evm, GAS_ZERO + extend_memory.cost) |
144 | |
145 | # OPERATION |
146 | evm.memory += b"\x00" * extend_memory.expand_by |
147 | evm.output = memory_read_bytes( |
148 | evm.memory, memory_start_position, memory_size |
149 | ) |
150 | |
151 | evm.running = False |
152 | |
153 | # PROGRAM COUNTER |
154 | 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, memory_input_start_position: U256, memory_input_size: U256, memory_output_start_position: U256, memory_output_size: U256) -> None:
169 | """ |
---|---|
170 | Perform the core logic of the `CALL*` family of opcodes. |
171 | """ |
172 | from ...vm.interpreter import STACK_DEPTH_LIMIT, process_message |
173 | |
174 | if evm.message.depth + Uint(1) > STACK_DEPTH_LIMIT: |
175 | evm.gas_left += gas |
176 | push(evm.stack, U256(0)) |
177 | return |
178 | |
179 | call_data = memory_read_bytes( |
180 | evm.memory, memory_input_start_position, memory_input_size |
181 | ) |
182 | code = get_account(evm.env.state, code_address).code |
183 | child_message = Message( |
184 | caller=caller, |
185 | target=to, |
186 | gas=gas, |
187 | value=value, |
188 | data=call_data, |
189 | code=code, |
190 | current_target=to, |
191 | depth=evm.message.depth + Uint(1), |
192 | code_address=code_address, |
193 | parent_evm=evm, |
194 | ) |
195 | child_evm = process_message(child_message, evm.env) |
196 | |
197 | if child_evm.error: |
198 | incorporate_child_on_error(evm, child_evm) |
199 | push(evm.stack, U256(0)) |
200 | else: |
201 | incorporate_child_on_success(evm, child_evm) |
202 | push(evm.stack, U256(1)) |
203 | |
204 | actual_output_size = min(memory_output_size, U256(len(child_evm.output))) |
205 | memory_write( |
206 | evm.memory, |
207 | memory_output_start_position, |
208 | child_evm.output[:actual_output_size], |
209 | ) |
call
Message-call into an account.
Parameters
evm : The current EVM frame.
def call(evm: Evm) -> None:
213 | """ |
---|---|
214 | Message-call into an account. |
215 |
|
216 | Parameters |
217 | ---------- |
218 | evm : |
219 | The current EVM frame. |
220 | """ |
221 | # STACK |
222 | gas = Uint(pop(evm.stack)) |
223 | to = to_address(pop(evm.stack)) |
224 | value = pop(evm.stack) |
225 | memory_input_start_position = pop(evm.stack) |
226 | memory_input_size = pop(evm.stack) |
227 | memory_output_start_position = pop(evm.stack) |
228 | memory_output_size = pop(evm.stack) |
229 | |
230 | # GAS |
231 | extend_memory = calculate_gas_extend_memory( |
232 | evm.memory, |
233 | [ |
234 | (memory_input_start_position, memory_input_size), |
235 | (memory_output_start_position, memory_output_size), |
236 | ], |
237 | ) |
238 | message_call_gas = calculate_message_call_gas( |
239 | evm.env.state, gas, to, value |
240 | ) |
241 | charge_gas(evm, message_call_gas.cost + extend_memory.cost) |
242 | |
243 | # OPERATION |
244 | evm.memory += b"\x00" * extend_memory.expand_by |
245 | sender_balance = get_account( |
246 | evm.env.state, evm.message.current_target |
247 | ).balance |
248 | if sender_balance < value: |
249 | push(evm.stack, U256(0)) |
250 | evm.gas_left += message_call_gas.stipend |
251 | else: |
252 | generic_call( |
253 | evm, |
254 | message_call_gas.stipend, |
255 | value, |
256 | evm.message.current_target, |
257 | to, |
258 | to, |
259 | memory_input_start_position, |
260 | memory_input_size, |
261 | memory_output_start_position, |
262 | memory_output_size, |
263 | ) |
264 | |
265 | # PROGRAM COUNTER |
266 | 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:
270 | """ |
---|---|
271 | Message-call into this account with alternative account’s code. |
272 |
|
273 | Parameters |
274 | ---------- |
275 | evm : |
276 | The current EVM frame. |
277 | """ |
278 | # STACK |
279 | gas = Uint(pop(evm.stack)) |
280 | code_address = to_address(pop(evm.stack)) |
281 | value = pop(evm.stack) |
282 | memory_input_start_position = pop(evm.stack) |
283 | memory_input_size = pop(evm.stack) |
284 | memory_output_start_position = pop(evm.stack) |
285 | memory_output_size = pop(evm.stack) |
286 | |
287 | # GAS |
288 | to = evm.message.current_target |
289 | |
290 | extend_memory = calculate_gas_extend_memory( |
291 | evm.memory, |
292 | [ |
293 | (memory_input_start_position, memory_input_size), |
294 | (memory_output_start_position, memory_output_size), |
295 | ], |
296 | ) |
297 | message_call_gas = calculate_message_call_gas( |
298 | evm.env.state, gas, to, value |
299 | ) |
300 | charge_gas(evm, message_call_gas.cost + extend_memory.cost) |
301 | |
302 | # OPERATION |
303 | evm.memory += b"\x00" * extend_memory.expand_by |
304 | sender_balance = get_account( |
305 | evm.env.state, evm.message.current_target |
306 | ).balance |
307 | if sender_balance < value: |
308 | push(evm.stack, U256(0)) |
309 | evm.gas_left += message_call_gas.stipend |
310 | else: |
311 | generic_call( |
312 | evm, |
313 | message_call_gas.stipend, |
314 | value, |
315 | evm.message.current_target, |
316 | to, |
317 | code_address, |
318 | memory_input_start_position, |
319 | memory_input_size, |
320 | memory_output_start_position, |
321 | memory_output_size, |
322 | ) |
323 | |
324 | # PROGRAM COUNTER |
325 | evm.pc += Uint(1) |
selfdestruct
Halt execution and register account for later deletion.
Parameters
evm : The current EVM frame.
def selfdestruct(evm: Evm) -> None:
329 | """ |
---|---|
330 | Halt execution and register account for later deletion. |
331 |
|
332 | Parameters |
333 | ---------- |
334 | evm : |
335 | The current EVM frame. |
336 | """ |
337 | # STACK |
338 | beneficiary = to_address(pop(evm.stack)) |
339 | |
340 | # GAS |
341 | gas_cost = GAS_ZERO |
342 | |
343 | originator = evm.message.current_target |
344 | |
345 | refunded_accounts = evm.accounts_to_delete |
346 | parent_evm = evm.message.parent_evm |
347 | while parent_evm is not None: |
348 | refunded_accounts.update(parent_evm.accounts_to_delete) |
349 | parent_evm = parent_evm.message.parent_evm |
350 | |
351 | if originator not in refunded_accounts: |
352 | evm.refund_counter += int(REFUND_SELF_DESTRUCT) |
353 | |
354 | charge_gas(evm, gas_cost) |
355 | |
356 | # OPERATION |
357 | beneficiary_balance = get_account(evm.env.state, beneficiary).balance |
358 | originator_balance = get_account(evm.env.state, originator).balance |
359 | |
360 | # First Transfer to beneficiary |
361 | set_account_balance( |
362 | evm.env.state, beneficiary, beneficiary_balance + originator_balance |
363 | ) |
364 | # Next, Zero the balance of the address being deleted (must come after |
365 | # sending to beneficiary in case the contract named itself as the |
366 | # beneficiary). |
367 | set_account_balance(evm.env.state, originator, U256(0)) |
368 | |
369 | # register account for deletion |
370 | evm.accounts_to_delete.add(originator) |
371 | |
372 | # HALT the execution |
373 | evm.running = False |
374 | |
375 | # PROGRAM COUNTER |
376 | pass |