async def _compute_sec_keys(state: State, tsx_data: MoneroTransactionData):
"""
Generate master key H( H(TsxData || tx_priv) || rand )
"""
import protobuf
from apps.monero.xmr.keccak_hasher import get_keccak_writer
writer = get_keccak_writer()
await protobuf.dump_message(writer, tsx_data)
writer.write(crypto.encodeint(state.tx_priv))
master_key = crypto.keccak_2hash(writer.get_digest() +
crypto.encodeint(crypto.random_scalar()))
state.key_hmac = crypto.keccak_2hash(b"hmac" + master_key)
state.key_enc = crypto.keccak_2hash(b"enc" + master_key)
def _build_key(secret,
discriminator=None,
index: int = None,
out: bytes = None) -> bytes:
"""
Creates an unique-purpose key
"""
key_buff = BUILD_KEY_BUFFER # bytearray(32 + 12 + 4) # key + disc + index
utils.ensure(len(secret) == 32, "Invalid key length")
utils.ensure(len(discriminator) <= 12, "Disc too long")
offset = 32
utils.memcpy(key_buff, 0, secret, 0, 32)
for i in range(32, len(key_buff)):
key_buff[i] = 0
if discriminator is not None:
utils.memcpy(key_buff, offset, discriminator, 0, len(discriminator))
offset += len(discriminator)
if index is not None:
# dump_uvarint_b_into, saving import
shifted = True
while shifted:
shifted = index >> 7
key_buff[offset] = (index & 0x7F) | (0x80 if shifted else 0x00)
offset += 1
index = shifted
return crypto.keccak_2hash(key_buff, out)
def _build_key(secret,
discriminator=None,
index: int = None,
out: bytes = None) -> bytes:
"""
Creates an unique-purpose key
"""
key_buff = _BUILD_KEY_BUFFER
utils.ensure(len(secret) == _SECRET_LENGTH, "Invalid key length")
utils.ensure(len(discriminator) <= _DISCRIMINATOR_LENGTH, "Disc too long")
offset = _SECRET_LENGTH
utils.memcpy(key_buff, 0, secret, 0, _SECRET_LENGTH)
for i in range(_SECRET_LENGTH, len(key_buff)):
key_buff[i] = 0
utils.memcpy(key_buff, offset, discriminator, 0, len(discriminator))
offset += _DISCRIMINATOR_LENGTH # fixed domain separator size
if index is not None:
# dump_uvarint_b_into, saving import
shifted = True
while shifted:
shifted = index >> 7
key_buff[offset] = (index & 0x7F) | (0x80 if shifted else 0x00)
offset += 1
index = shifted
return crypto.keccak_2hash(key_buff, out)
def compute_enc_key_host(view_key_private: Sc25519,
tx_prefix_hash: bytes) -> Tuple[bytes, bytes]:
from apps.monero.xmr import crypto
salt = crypto.random_bytes(32)
passwd = crypto.keccak_2hash(
crypto.encodeint(view_key_private) + tx_prefix_hash)
tx_key = crypto.compute_hmac(salt, passwd)
return tx_key, salt
def _compute_tx_key(spend_key_private, tx_prefix_hash):
salt = crypto.random_bytes(32)
rand_mult_num = crypto.random_scalar()
rand_mult = crypto.encodeint(rand_mult_num)
rand_inp = crypto.sc_add(spend_key_private, rand_mult_num)
passwd = crypto.keccak_2hash(crypto.encodeint(rand_inp) + tx_prefix_hash)
tx_key = crypto.compute_hmac(salt, passwd)
return tx_key, salt, rand_mult
def compute_tx_key(
spend_key_private: Sc25519,
tx_prefix_hash: bytes,
salt: bytes,
rand_mult_num: Sc25519,
) -> bytes:
from apps.monero.xmr import crypto
rand_inp = crypto.sc_add(spend_key_private, rand_mult_num)
passwd = crypto.keccak_2hash(crypto.encodeint(rand_inp) + tx_prefix_hash)
tx_key = crypto.compute_hmac(salt, passwd)
return tx_key
def _build_key(secret, discriminator=None, index: int = None) -> bytes:
"""
Creates an unique-purpose key
"""
key_buff = bytearray(32 + 12 + 4) # key + disc + index
offset = 32
utils.memcpy(key_buff, 0, secret, 0, len(secret))
if discriminator is not None:
utils.memcpy(key_buff, offset, discriminator, 0, len(discriminator))
offset += len(discriminator)
if index is not None:
# dump_uvarint_b_into, saving import
shifted = True
while shifted:
shifted = index >> 7
key_buff[offset] = (index & 0x7F) | (0x80 if shifted else 0x00)
offset += 1
index = shifted
return crypto.keccak_2hash(key_buff)
