def _get_primary_change_address(state: State) -> MoneroAccountPublicAddress:
"""
Computes primary change address for the current account index
"""
from trezor.messages import MoneroAccountPublicAddress
D, C = monero.generate_sub_address_keys(state.creds.view_key_private,
state.creds.spend_key_public,
state.account_idx, 0)
return MoneroAccountPublicAddress(view_public_key=crypto.encodepoint(C),
spend_public_key=crypto.encodepoint(D))
def _get_key_for_payment_id_encryption(
tsx_data: MoneroTransactionData,
change_addr: MoneroAccountPublicAddress | None = None,
add_dummy_payment_id: bool = False,
) -> bytes:
"""
Returns destination address public view key to be used for
payment id encryption. If no encrypted payment ID is chosen,
dummy payment ID is set for better transaction uniformity if possible.
"""
from apps.monero.xmr.addresses import addr_eq
from trezor.messages import MoneroAccountPublicAddress
addr = MoneroAccountPublicAddress(
spend_public_key=crypto_helpers.NULL_KEY_ENC,
view_public_key=crypto_helpers.NULL_KEY_ENC,
)
count = 0
for dest in tsx_data.outputs:
if dest.amount == 0:
continue
if change_addr and addr_eq(dest.addr, change_addr):
continue
if addr_eq(dest.addr, addr):
continue
if count > 0 and tsx_data.payment_id:
raise ValueError(
"Destinations have to have exactly one output to support encrypted payment ids"
)
addr = dest.addr
count += 1
# Insert dummy payment id for transaction uniformity
if not tsx_data.payment_id and count <= 1 and add_dummy_payment_id:
tsx_data.payment_id = bytearray(8)
if count == 0 and change_addr:
return change_addr.view_public_key
if addr.view_public_key == crypto_helpers.NULL_KEY_ENC:
raise ValueError("Invalid key")
return addr.view_public_key