def precompile_ecrecover(computation):
computation.gas_meter.consume_gas(constants.GAS_ECRECOVER, reason="ECRecover Precompile")
raw_message_hash = computation.msg.data[:32]
message_hash = pad32r(raw_message_hash)
v_bytes = pad32r(computation.msg.data[32:64])
v = big_endian_to_int(v_bytes)
r_bytes = pad32r(computation.msg.data[64:96])
r = big_endian_to_int(r_bytes)
s_bytes = pad32r(computation.msg.data[96:128])
s = big_endian_to_int(s_bytes)
try:
validate_lt_secpk1n(r)
validate_lt_secpk1n(s)
validate_lte(v, 28)
validate_gte(v, 27)
except ValidationError:
return computation
try:
raw_public_key = ecdsa_raw_recover(message_hash, (v, r, s))
except ValueError:
return computation
public_key = encode_raw_public_key(raw_public_key)
address = public_key_to_address(public_key)
padded_address = pad32(address)
computation.output = padded_address
return computation
def extract_transaction_sender(transaction):
unsigned_transaction = transaction.as_unsigned_transaction()
signature = encode_signature(
v=transaction.v,
r=transaction.r,
s=transaction.s,
)
public_key = ecdsa_recover(rlp.encode(unsigned_transaction), signature)
sender = public_key_to_address(public_key)
return sender
def extract_transaction_sender(transaction):
vrs = (transaction.v, transaction.r, transaction.s)
unsigned_transaction = transaction.as_unsigned_transaction()
raw_public_key = get_ecc_backend().ecdsa_raw_recover(
keccak(rlp.encode(unsigned_transaction)),
vrs,
)
public_key = encode_raw_public_key(raw_public_key)
sender = public_key_to_address(public_key)
return sender