trezor-firmware/src/apps/nem/helpers.py

from micropython import const

from apps.common import HARDENED

NEM_NETWORK_MAINNET = const(0x68)
NEM_NETWORK_TESTNET = const(0x98)
NEM_NETWORK_MIJIN = const(0x60)

NEM_TRANSACTION_TYPE_TRANSFER = const(0x0101)
NEM_TRANSACTION_TYPE_IMPORTANCE_TRANSFER = const(0x0801)
NEM_TRANSACTION_TYPE_AGGREGATE_MODIFICATION = const(0x1001)
NEM_TRANSACTION_TYPE_MULTISIG_SIGNATURE = const(0x1002)
NEM_TRANSACTION_TYPE_MULTISIG = const(0x1004)
NEM_TRANSACTION_TYPE_PROVISION_NAMESPACE = const(0x2001)
NEM_TRANSACTION_TYPE_MOSAIC_CREATION = const(0x4001)
NEM_TRANSACTION_TYPE_MOSAIC_SUPPLY_CHANGE = const(0x4002)

NEM_MAX_DIVISIBILITY = const(6)
NEM_MAX_SUPPLY = const(9000000000)

NEM_SALT_SIZE = const(32)
AES_BLOCK_SIZE = const(16)
NEM_HASH_ALG = "keccak"
NEM_PUBLIC_KEY_SIZE = const(32)  # ed25519 public key
NEM_LEVY_PERCENTILE_DIVISOR_ABSOLUTE = const(10000)
NEM_MOSAIC_AMOUNT_DIVISOR = const(1000000)

NEM_MAX_PLAIN_PAYLOAD_SIZE = const(1024)
NEM_MAX_ENCRYPTED_PAYLOAD_SIZE = const(960)


def get_network_str(network: int) -> str:
    if network == NEM_NETWORK_MAINNET:
        return "Mainnet"
    elif network == NEM_NETWORK_TESTNET:
        return "Testnet"
    elif network == NEM_NETWORK_MIJIN:
        return "Mijin"


def check_path(path: list, network=None) -> bool:
    """
    Validates derivation path to fit 44'/43'/a' or 44'/43'/a'/0'/0',
    where `a` is an account number. We believe the path should be
    44'/43'/a', but for compatibility reasons with NEM's NanoWallet
    we allow 44'/43'/a'/0'/0' as well.
    Testnet is also allowed: 44'/1'/a'{/0'/0'}
    """
    length = len(path)
    if length != 3 and length != 5:
        return False
    if path[0] != 44 | HARDENED:
        return False
    if not (
        path[1] == 43 | HARDENED
        or (network == NEM_NETWORK_TESTNET and path[1] == 1 | HARDENED)
    ):
        return False
    if path[2] < HARDENED or path[2] > 1000000 | HARDENED:
        return False
    if length == 5 and (path[3] != 0 | HARDENED or path[4] != 0 | HARDENED):
        return False
    return True