def __init__(self, bip32: Bip32Base, coin_conf: BipCoinConf) -> None:
"""
Construct class.
Args:
bip32 (Bip32Base object): Bip32Base object
coin_conf (BipCoinConf) : BipCoinConf object
Returns:
Bip44DepthError: If the Bip32 object depth is not valid
"""
depth = bip32.Depth()
# If the Bip32 is public-only, the depth shall start from the account level because hardened derivation is
# used below it, which is not possible with public keys
if bip32.IsPublicOnly():
if depth < Bip44Levels.ACCOUNT or depth > Bip44Levels.ADDRESS_INDEX:
raise Bip44DepthError(
f"Depth of the public-only Bip32 object ({depth}) is below account level or "
f"beyond address index level")
# If the Bip32 object is not public-only, any depth is fine as long as it is not greater
# than address index level
else:
if depth < 0 or depth > Bip44Levels.ADDRESS_INDEX:
raise Bip44DepthError(
f"Depth of the Bip32 object ({depth}) is invalid or beyond address index level"
)
# Finally, initialize class
self.m_bip32 = bip32
self.m_coin_conf = coin_conf
def _AddressIndexGeneric(cls, bip_obj: Bip44Base,
addr_idx: int) -> Bip44Base:
"""
Derive a child key from the specified address index and return a new Bip44Base object.
It shall be called from a child class.
Args:
bip_obj (Bip44Base object): Bip44Base object
addr_idx (int) : Address index
Returns:
Bip44Base object: Bip44Base object
Raises:
Bip44DepthError: If the current depth is not suitable for deriving keys
Bip32KeyError: If the derivation results in an invalid key
"""
if not cls.IsLevel(bip_obj, Bip44Levels.CHANGE):
raise Bip44DepthError(
f"Current depth ({bip_obj.m_bip32.Depth().ToInt()}) is not suitable for deriving address"
)
# Use hardened derivation if not-hardended is not supported
if not bip_obj.m_bip32.IsPrivateUnhardenedDerivationSupported():
addr_idx = Bip32Utils.HardenIndex(addr_idx)
return cls(bip_obj.m_bip32.ChildKey(addr_idx), bip_obj.m_coin_conf)
def _ChangeGeneric(cls, bip_obj: Bip44Base,
change_type: Bip44Changes) -> Bip44Base:
"""
Derive a child key from the specified chain type and return a new Bip44Base object.
It shall be called from a child class.
Args:
bip_obj (Bip44Base object): Bip44Base object
change_type (Bip44Changes): Change type, must a Bip44Changes enum
Returns:
Bip44Base object: Bip44Base object
Raises:
TypeError: If chain index is not a Bip44Changes enum
Bip44DepthError: If the current depth is not suitable for deriving keys
Bip32KeyError: If the derivation results in an invalid key
"""
if not isinstance(change_type, Bip44Changes):
raise TypeError(
"Change index is not an enumerative of Bip44Changes")
if not cls.IsLevel(bip_obj, Bip44Levels.ACCOUNT):
raise Bip44DepthError(
f"Current depth ({bip_obj.m_bip32.Depth().ToInt()}) is not suitable for deriving change"
)
# Use hardened derivation if not-hardended is not supported
if not bip_obj.m_bip32.IsPrivateUnhardenedDerivationSupported():
change_idx = Bip32Utils.HardenIndex(int(change_type))
else:
change_idx = int(change_type)
return cls(bip_obj.m_bip32.ChildKey(change_idx), bip_obj.m_coin_conf)
def _DeriveDefaultPathGeneric(cls, bip_obj: Bip44Base,
purpose: int) -> Bip44Base:
"""
Derive the default coin path and return a new Bip44Base object.
It shall be called from a child class.
Args:
bip_obj (Bip44Base object): Bip44Base object
purpose (int) : Purpose
Returns:
Bip44Base object: Bip44Base object
Raises:
Bip44DepthError: If the current depth is not suitable for deriving keys
Bip32KeyError: If the derivation results in an invalid key
"""
if not cls.IsLevel(bip_obj, Bip44Levels.MASTER):
raise Bip44DepthError(
f"Current depth ({bip_obj.m_bip32.Depth().ToInt()}) is not suitable for deriving default path"
)
# Derive purpose and coin by default
bip_obj = cls._PurposeGeneric(bip_obj, purpose)
bip_obj = cls._CoinGeneric(bip_obj)
# Derive the remaining path
return cls(
bip_obj.m_bip32.DerivePath(bip_obj.m_coin_conf.DefaultPath()),
bip_obj.m_coin_conf)
def _PurposeGeneric(cls, bip_obj: Bip44Base, purpose: int) -> Bip44Base:
"""
Derive a child key from the purpose and return a new Bip44Base object.
It shall be called from a child class.
Args:
bip_obj (Bip44Base object): Bip44Base object
purpose (int) : Purpose
Returns:
Bip44Base object: Bip44Base object
Raises:
Bip44DepthError: If the current depth is not suitable for deriving keys
Bip32KeyError: If the derivation results in an invalid key
"""
if not cls.IsLevel(bip_obj, Bip44Levels.MASTER):
raise Bip44DepthError(
f"Current depth ({bip_obj.m_bip32.Depth().ToInt()}) is not suitable for deriving purpose"
)
return cls(bip_obj.m_bip32.ChildKey(purpose), bip_obj.m_coin_conf)
def _AccountGeneric(cls, bip_obj: Bip44Base, acc_idx: int) -> Bip44Base:
"""
Derive a child key from the specified account index and return a new Bip44Base object.
It shall be called from a child class.
Args:
bip_obj (Bip44Base object): Bip44Base object
acc_idx (int) : Account index
Returns:
Bip44Base object: Bip44Base object
Raises:
Bip44DepthError: If the current depth is not suitable for deriving keys
Bip32KeyError: If the derivation results in an invalid key
"""
if not cls.IsLevel(bip_obj, Bip44Levels.COIN):
raise Bip44DepthError(
f"Current depth ({bip_obj.m_bip32.Depth().ToInt()}) is not suitable for deriving account"
)
return cls(bip_obj.m_bip32.ChildKey(Bip32Utils.HardenIndex(acc_idx)),
bip_obj.m_coin_conf)
def _CoinGeneric(cls, bip_obj: Bip44Base) -> Bip44Base:
"""
Derive a child key from the coin type specified at construction and return a new Bip44Base object.
It shall be called from a child class.
Args:
bip_obj (Bip44Base object): Bip44Base object
Returns:
Bip44Base object: Bip44Base object
Raises:
Bip44DepthError: If the current depth is not suitable for deriving keys
Bip32KeyError: If the derivation results in an invalid key
"""
if not cls.IsLevel(bip_obj, Bip44Levels.PURPOSE):
raise Bip44DepthError(
f"Current depth ({bip_obj.m_bip32.Depth().ToInt()}) is not suitable for deriving coin"
)
coin_idx = bip_obj.m_coin_conf.CoinIndex()
return cls(bip_obj.m_bip32.ChildKey(Bip32Utils.HardenIndex(coin_idx)),
bip_obj.m_coin_conf)