cic-stack/apps/cic-eth/cic_eth/eth/util.py
2021-02-17 08:19:42 +00:00

109 lines
2.8 KiB
Python

# standard imports
import logging
import sha3
import web3
# third-party imports
from rlp import decode as rlp_decode
from rlp import encode as rlp_encode
from eth_keys import KeyAPI
logg = logging.getLogger()
field_debugs = [
'nonce',
'gasPrice',
'gas',
'to',
'value',
'data',
'v',
'r',
's',
]
def unpack_signed_raw_tx(tx_raw_bytes, chain_id):
d = rlp_decode(tx_raw_bytes)
logg.debug('decoding using chain id {}'.format(chain_id))
j = 0
for i in d:
logg.debug('decoded {}: {}'.format(field_debugs[j], i.hex()))
j += 1
vb = chain_id
if chain_id != 0:
v = int.from_bytes(d[6], 'big')
vb = v - (chain_id * 2) - 35
while len(d[7]) < 32:
d[7] = b'\x00' + d[7]
while len(d[8]) < 32:
d[8] = b'\x00' + d[8]
s = b''.join([d[7], d[8], bytes([vb])])
so = KeyAPI.Signature(signature_bytes=s)
h = sha3.keccak_256()
h.update(rlp_encode(d))
signed_hash = h.digest()
d[6] = chain_id
d[7] = b''
d[8] = b''
h = sha3.keccak_256()
h.update(rlp_encode(d))
unsigned_hash = h.digest()
p = so.recover_public_key_from_msg_hash(unsigned_hash)
a = p.to_checksum_address()
logg.debug('decoded recovery byte {}'.format(vb))
logg.debug('decoded address {}'.format(a))
logg.debug('decoded signed hash {}'.format(signed_hash.hex()))
logg.debug('decoded unsigned hash {}'.format(unsigned_hash.hex()))
to = d[3].hex() or None
if to != None:
to = web3.Web3.toChecksumAddress('0x' + to)
return {
'from': a,
'nonce': int.from_bytes(d[0], 'big'),
'gasPrice': int.from_bytes(d[1], 'big'),
'gas': int.from_bytes(d[2], 'big'),
'to': to,
'value': int.from_bytes(d[4], 'big'),
'data': '0x' + d[5].hex(),
'v': chain_id,
'r': '0x' + s[:32].hex(),
's': '0x' + s[32:64].hex(),
'chainId': chain_id,
'hash': '0x' + signed_hash.hex(),
'hash_unsigned': '0x' + unsigned_hash.hex(),
}
def unpack_signed_raw_tx_hex(tx_raw_hex, chain_id):
return unpack_signed_raw_tx(bytes.fromhex(tx_raw_hex[2:]), chain_id)
# TODO: consider moving tx string representation generation from api_admin to here
def tx_string(tx_raw_bytes, chain_id):
tx_unpacked = unpack_signed_raw_tx(tx_raw_bytes, chain_id)
return 'tx nonce {} from {} to {} hash {}'.format(
tx_unpacked['nonce'],
tx_unpacked['from'],
tx_unpacked['to'],
tx_unpacked['hash'],
)
def tx_hex_string(tx_hex, chain_id):
if len(tx_hex) < 2:
raise ValueError('invalid data length')
elif tx_hex[:2] == '0x':
tx_hex = tx_hex[2:]
tx_raw_bytes = bytes.fromhex(tx_hex)
return tx_string(tx_raw_bytes, chain_id)