def get_total_length(msg: EthereumSignTx, data_total: int) -> int:
length = 0
if msg.tx_type is not None:
length += rlp.field_length(1, [msg.tx_type])
length += rlp.field_length(len(msg.nonce), msg.nonce[:1])
length += rlp.field_length(len(msg.gas_price), msg.gas_price)
length += rlp.field_length(len(msg.gas_limit), msg.gas_limit)
to = address.bytes_from_address(msg.to)
length += rlp.field_length(len(to), to)
length += rlp.field_length(len(msg.value), msg.value)
if msg.chain_id: # forks replay protection
if msg.chain_id < 0x100:
l = 1
elif msg.chain_id < 0x10000:
l = 2
elif msg.chain_id < 0x1000000:
l = 3
else:
l = 4
length += rlp.field_length(l, [msg.chain_id])
length += rlp.field_length(0, 0)
length += rlp.field_length(0, 0)
length += rlp.field_length(data_total, msg.data_initial_chunk)
return length
async def verify_message(ctx, msg):
digest = message_digest(msg.message)
if len(msg.signature) != 65:
raise wire.DataError("Invalid signature")
sig = bytearray([msg.signature[64]]) + msg.signature[:64]
try:
pubkey = secp256k1.verify_recover(sig, digest)
except ValueError:
raise wire.DataError("Invalid signature")
if not pubkey:
raise wire.DataError("Invalid signature")
pkh = sha3_256(pubkey[1:], keccak=True).digest()[-20:]
address_bytes = bytes_from_address(msg.address)
if address_bytes != pkh:
raise wire.DataError("Invalid signature")
address = address_from_bytes(address_bytes)
await require_confirm_verify_message(ctx, address, msg.message)
return Success(message="Message verified")
async def sign_tx(ctx, msg, keychain):
msg = sanitize(msg)
check(msg)
await paths.validate_path(ctx, validate_full_path, path=msg.address_n)
data_total = msg.data_length
# detect ERC - 20 token
token = None
address_bytes = recipient = address.bytes_from_address(msg.to)
value = int.from_bytes(msg.value, "big")
if (len(msg.to) in (40, 42) and len(msg.value) == 0 and data_total == 68
and len(msg.data_initial_chunk) == 68
and msg.data_initial_chunk[:16] ==
b"\xa9\x05\x9c\xbb\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
):
token = tokens.token_by_chain_address(msg.chain_id, address_bytes)
recipient = msg.data_initial_chunk[16:36]
value = int.from_bytes(msg.data_initial_chunk[36:68], "big")
await require_confirm_tx(ctx, recipient, value, msg.chain_id, token,
msg.tx_type)
if token is None and msg.data_length > 0:
await require_confirm_data(ctx, msg.data_initial_chunk, data_total)
await require_confirm_fee(
ctx,
value,
int.from_bytes(msg.gas_price, "big"),
int.from_bytes(msg.gas_limit, "big"),
msg.chain_id,
token,
msg.tx_type,
)
data = bytearray()
data += msg.data_initial_chunk
data_left = data_total - len(msg.data_initial_chunk)
total_length = get_total_length(msg, data_total)
sha = HashWriter(sha3_256(keccak=True))
sha.extend(rlp.encode_length(total_length, True)) # total length
if msg.tx_type is not None:
sha.extend(rlp.encode(msg.tx_type))
for field in (msg.nonce, msg.gas_price, msg.gas_limit, address_bytes,
msg.value):
sha.extend(rlp.encode(field))
if data_left == 0:
sha.extend(rlp.encode(data))
else:
sha.extend(rlp.encode_length(data_total, False))
sha.extend(rlp.encode(data, False))
while data_left > 0:
resp = await send_request_chunk(ctx, data_left)
data_left -= len(resp.data_chunk)
sha.extend(resp.data_chunk)
# eip 155 replay protection
if msg.chain_id:
sha.extend(rlp.encode(msg.chain_id))
sha.extend(rlp.encode(0))
sha.extend(rlp.encode(0))
digest = sha.get_digest()
result = sign_digest(msg, keychain, digest)
return result