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:
43 | """ |
---|---|
44 | Creates a new account with associated code. |
45 |
|
46 | Parameters |
47 | ---------- |
48 | evm : |
49 | The current EVM frame. |
50 | """ |
51 | # This import causes a circular import error |
52 | # if it's not moved inside this method |
53 | from ...vm.interpreter import STACK_DEPTH_LIMIT, process_create_message |
54 | |
55 | # STACK |
56 | endowment = pop(evm.stack) |
57 | memory_start_position = pop(evm.stack) |
58 | memory_size = pop(evm.stack) |
59 | |
60 | # GAS |
61 | extend_memory = calculate_gas_extend_memory( |
62 | evm.memory, [(memory_start_position, memory_size)] |
63 | ) |
64 | |
65 | charge_gas(evm, GAS_CREATE + extend_memory.cost) |
66 | |
67 | create_message_gas = evm.gas_left |
68 | evm.gas_left = Uint(0) |
69 | |
70 | # OPERATION |
71 | evm.memory += b"\x00" * extend_memory.expand_by |
72 | sender_address = evm.message.current_target |
73 | sender = get_account(evm.env.state, sender_address) |
74 | |
75 | contract_address = compute_contract_address( |
76 | evm.message.current_target, |
77 | get_account(evm.env.state, evm.message.current_target).nonce, |
78 | ) |
79 | |
80 | if ( |
81 | sender.balance < endowment |
82 | or sender.nonce == Uint(2**64 - 1) |
83 | or evm.message.depth + 1 > STACK_DEPTH_LIMIT |
84 | ): |
85 | push(evm.stack, U256(0)) |
86 | evm.gas_left += create_message_gas |
87 | elif account_has_code_or_nonce(evm.env.state, contract_address): |
88 | increment_nonce(evm.env.state, evm.message.current_target) |
89 | push(evm.stack, U256(0)) |
90 | else: |
91 | call_data = memory_read_bytes( |
92 | evm.memory, memory_start_position, memory_size |
93 | ) |
94 |
|
95 | increment_nonce(evm.env.state, evm.message.current_target) |
96 |
|
97 | child_message = Message( |
98 | caller=evm.message.current_target, |
99 | target=Bytes0(), |
100 | gas=create_message_gas, |
101 | value=endowment, |
102 | data=b"", |
103 | code=call_data, |
104 | current_target=contract_address, |
105 | depth=evm.message.depth + 1, |
106 | code_address=None, |
107 | parent_evm=evm, |
108 | ) |
109 | child_evm = process_create_message(child_message, evm.env) |
110 |
|
111 | if child_evm.error: |
112 | incorporate_child_on_error(evm, child_evm) |
113 | push(evm.stack, U256(0)) |
114 | else: |
115 | incorporate_child_on_success(evm, child_evm) |
116 | push( |
117 | evm.stack, U256.from_be_bytes(child_evm.message.current_target) |
118 | ) |
119 | |
120 | # PROGRAM COUNTER |
121 | evm.pc += 1 |
return_
Halts execution returning output data.
Parameters
evm : The current EVM frame.
def return_(evm: Evm) -> None:
125 | """ |
---|---|
126 | Halts execution returning output data. |
127 |
|
128 | Parameters |
129 | ---------- |
130 | evm : |
131 | The current EVM frame. |
132 | """ |
133 | # STACK |
134 | memory_start_position = pop(evm.stack) |
135 | memory_size = pop(evm.stack) |
136 | |
137 | # GAS |
138 | extend_memory = calculate_gas_extend_memory( |
139 | evm.memory, [(memory_start_position, memory_size)] |
140 | ) |
141 | |
142 | charge_gas(evm, GAS_ZERO + extend_memory.cost) |
143 | |
144 | # OPERATION |
145 | evm.memory += b"\x00" * extend_memory.expand_by |
146 | evm.output = memory_read_bytes( |
147 | evm.memory, memory_start_position, memory_size |
148 | ) |
149 | |
150 | evm.running = False |
151 | |
152 | # PROGRAM COUNTER |
153 | 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:
168 | """ |
---|---|
169 | Perform the core logic of the `CALL*` family of opcodes. |
170 | """ |
171 | from ...vm.interpreter import STACK_DEPTH_LIMIT, process_message |
172 | |
173 | if evm.message.depth + 1 > STACK_DEPTH_LIMIT: |
174 | evm.gas_left += gas |
175 | push(evm.stack, U256(0)) |
176 | return |
177 | |
178 | call_data = memory_read_bytes( |
179 | evm.memory, memory_input_start_position, memory_input_size |
180 | ) |
181 | code = get_account(evm.env.state, code_address).code |
182 | child_message = Message( |
183 | caller=caller, |
184 | target=to, |
185 | gas=gas, |
186 | value=value, |
187 | data=call_data, |
188 | code=code, |
189 | current_target=to, |
190 | depth=evm.message.depth + 1, |
191 | code_address=code_address, |
192 | parent_evm=evm, |
193 | ) |
194 | child_evm = process_message(child_message, evm.env) |
195 | |
196 | if child_evm.error: |
197 | incorporate_child_on_error(evm, child_evm) |
198 | push(evm.stack, U256(0)) |
199 | else: |
200 | incorporate_child_on_success(evm, child_evm) |
201 | push(evm.stack, U256(1)) |
202 | |
203 | actual_output_size = min(memory_output_size, U256(len(child_evm.output))) |
204 | memory_write( |
205 | evm.memory, |
206 | memory_output_start_position, |
207 | child_evm.output[:actual_output_size], |
208 | ) |
call
Message-call into an account.
Parameters
evm : The current EVM frame.
def call(evm: Evm) -> None:
212 | """ |
---|---|
213 | Message-call into an account. |
214 |
|
215 | Parameters |
216 | ---------- |
217 | evm : |
218 | The current EVM frame. |
219 | """ |
220 | # STACK |
221 | gas = Uint(pop(evm.stack)) |
222 | to = to_address(pop(evm.stack)) |
223 | value = pop(evm.stack) |
224 | memory_input_start_position = pop(evm.stack) |
225 | memory_input_size = pop(evm.stack) |
226 | memory_output_start_position = pop(evm.stack) |
227 | memory_output_size = pop(evm.stack) |
228 | |
229 | # GAS |
230 | extend_memory = calculate_gas_extend_memory( |
231 | evm.memory, |
232 | [ |
233 | (memory_input_start_position, memory_input_size), |
234 | (memory_output_start_position, memory_output_size), |
235 | ], |
236 | ) |
237 | message_call_gas = calculate_message_call_gas( |
238 | evm.env.state, gas, to, value |
239 | ) |
240 | charge_gas(evm, message_call_gas.cost + extend_memory.cost) |
241 | |
242 | # OPERATION |
243 | evm.memory += b"\x00" * extend_memory.expand_by |
244 | sender_balance = get_account( |
245 | evm.env.state, evm.message.current_target |
246 | ).balance |
247 | if sender_balance < value: |
248 | push(evm.stack, U256(0)) |
249 | evm.gas_left += message_call_gas.stipend |
250 | else: |
251 | generic_call( |
252 | evm, |
253 | message_call_gas.stipend, |
254 | value, |
255 | evm.message.current_target, |
256 | to, |
257 | to, |
258 | memory_input_start_position, |
259 | memory_input_size, |
260 | memory_output_start_position, |
261 | memory_output_size, |
262 | ) |
263 | |
264 | # PROGRAM COUNTER |
265 | evm.pc += 1 |
callcode
Message-call into this account with alternative account’s code.
Parameters
evm : The current EVM frame.
def callcode(evm: Evm) -> None:
269 | """ |
---|---|
270 | Message-call into this account with alternative account’s code. |
271 |
|
272 | Parameters |
273 | ---------- |
274 | evm : |
275 | The current EVM frame. |
276 | """ |
277 | # STACK |
278 | gas = Uint(pop(evm.stack)) |
279 | code_address = to_address(pop(evm.stack)) |
280 | value = pop(evm.stack) |
281 | memory_input_start_position = pop(evm.stack) |
282 | memory_input_size = pop(evm.stack) |
283 | memory_output_start_position = pop(evm.stack) |
284 | memory_output_size = pop(evm.stack) |
285 | |
286 | # GAS |
287 | to = evm.message.current_target |
288 | |
289 | extend_memory = calculate_gas_extend_memory( |
290 | evm.memory, |
291 | [ |
292 | (memory_input_start_position, memory_input_size), |
293 | (memory_output_start_position, memory_output_size), |
294 | ], |
295 | ) |
296 | message_call_gas = calculate_message_call_gas( |
297 | evm.env.state, gas, to, value |
298 | ) |
299 | charge_gas(evm, message_call_gas.cost + extend_memory.cost) |
300 | |
301 | # OPERATION |
302 | evm.memory += b"\x00" * extend_memory.expand_by |
303 | sender_balance = get_account( |
304 | evm.env.state, evm.message.current_target |
305 | ).balance |
306 | if sender_balance < value: |
307 | push(evm.stack, U256(0)) |
308 | evm.gas_left += message_call_gas.stipend |
309 | else: |
310 | generic_call( |
311 | evm, |
312 | message_call_gas.stipend, |
313 | value, |
314 | evm.message.current_target, |
315 | to, |
316 | code_address, |
317 | memory_input_start_position, |
318 | memory_input_size, |
319 | memory_output_start_position, |
320 | memory_output_size, |
321 | ) |
322 | |
323 | # PROGRAM COUNTER |
324 | evm.pc += 1 |
selfdestruct
Halt execution and register account for later deletion.
Parameters
evm : The current EVM frame.
def selfdestruct(evm: Evm) -> None:
328 | """ |
---|---|
329 | Halt execution and register account for later deletion. |
330 |
|
331 | Parameters |
332 | ---------- |
333 | evm : |
334 | The current EVM frame. |
335 | """ |
336 | # STACK |
337 | beneficiary = to_address(pop(evm.stack)) |
338 | |
339 | # GAS |
340 | gas_cost = GAS_ZERO |
341 | |
342 | originator = evm.message.current_target |
343 | |
344 | refunded_accounts = evm.accounts_to_delete |
345 | parent_evm = evm.message.parent_evm |
346 | while parent_evm is not None: |
347 | refunded_accounts.update(parent_evm.accounts_to_delete) |
348 | parent_evm = parent_evm.message.parent_evm |
349 | |
350 | if originator not in refunded_accounts: |
351 | evm.refund_counter += REFUND_SELF_DESTRUCT |
352 | |
353 | charge_gas(evm, gas_cost) |
354 | |
355 | # OPERATION |
356 | beneficiary_balance = get_account(evm.env.state, beneficiary).balance |
357 | originator_balance = get_account(evm.env.state, originator).balance |
358 | |
359 | # First Transfer to beneficiary |
360 | set_account_balance( |
361 | evm.env.state, beneficiary, beneficiary_balance + originator_balance |
362 | ) |
363 | # Next, Zero the balance of the address being deleted (must come after |
364 | # sending to beneficiary in case the contract named itself as the |
365 | # beneficiary). |
366 | set_account_balance(evm.env.state, originator, U256(0)) |
367 | |
368 | # register account for deletion |
369 | evm.accounts_to_delete.add(originator) |
370 | |
371 | # HALT the execution |
372 | evm.running = False |
373 | |
374 | # PROGRAM COUNTER |
375 | pass |