lbry-sdk/torba/baseaccount.py
2018-07-29 13:13:40 -04:00

313 lines
12 KiB
Python

import typing
from typing import Tuple, Type
from twisted.internet import defer
from torba.mnemonic import Mnemonic
from torba.bip32 import PrivateKey, PubKey, from_extended_key_string
from torba.hash import double_sha256, aes_encrypt, aes_decrypt
if typing.TYPE_CHECKING:
from torba import baseledger
class AddressManager:
name: str
__slots__ = 'account', 'public_key', 'chain_number'
def __init__(self, account, public_key, chain_number):
self.account = account
self.public_key = public_key
self.chain_number = chain_number
@classmethod
def from_dict(cls, account: 'BaseAccount', d: dict) \
-> Tuple['AddressManager', 'AddressManager']:
raise NotImplementedError
@classmethod
def to_dict(cls, receiving: 'AddressManager', change: 'AddressManager') -> dict:
return {'name': cls.name}
@property
def db(self):
return self.account.ledger.db
def _query_addresses(self, limit: int = None, max_used_times: int = None, order_by=None):
return self.db.get_addresses(
self.account, self.chain_number, limit, max_used_times, order_by
)
def get_private_key(self, index: int) -> PrivateKey:
raise NotImplementedError
def get_max_gap(self) -> defer.Deferred:
raise NotImplementedError
def ensure_address_gap(self) -> defer.Deferred:
raise NotImplementedError
def get_address_records(self, limit: int = None, only_usable: bool = False) -> defer.Deferred:
raise NotImplementedError
@defer.inlineCallbacks
def get_addresses(self, limit: int = None, only_usable: bool = False) -> defer.Deferred:
records = yield self.get_address_records(limit=limit, only_usable=only_usable)
defer.returnValue([r['address'] for r in records])
@defer.inlineCallbacks
def get_or_create_usable_address(self) -> defer.Deferred:
addresses = yield self.get_addresses(limit=1, only_usable=True)
if addresses:
defer.returnValue(addresses[0])
addresses = yield self.ensure_address_gap()
defer.returnValue(addresses[0])
class HierarchicalDeterministic(AddressManager):
""" Implements simple version of Bitcoin Hierarchical Deterministic key management. """
name = "deterministic-chain"
__slots__ = 'gap', 'maximum_uses_per_address'
def __init__(self, account: 'BaseAccount', chain: int, gap: int, maximum_uses_per_address: int) -> None:
super().__init__(account, account.public_key.child(chain), chain)
self.gap = gap
self.maximum_uses_per_address = maximum_uses_per_address
@classmethod
def from_dict(cls, account: 'BaseAccount', d: dict) -> Tuple[AddressManager, AddressManager]:
return (
cls(account, 0, **d.get('receiving', {'gap': 20, 'maximum_uses_per_address': 2})),
cls(account, 1, **d.get('change', {'gap': 6, 'maximum_uses_per_address': 2}))
)
@classmethod
def to_dict(cls, receiving: 'HierarchicalDeterministic', change: 'HierarchicalDeterministic') -> dict:
d = super().to_dict(receiving, change)
d['receiving'] = receiving.to_dict_instance()
d['change'] = change.to_dict_instance()
return d
def to_dict_instance(self):
return {'gap': self.gap, 'maximum_uses_per_address': self.maximum_uses_per_address}
def get_private_key(self, index: int) -> PrivateKey:
return self.account.private_key.child(self.chain_number).child(index)
@defer.inlineCallbacks
def generate_keys(self, start: int, end: int) -> defer.Deferred:
new_keys = []
for index in range(start, end+1):
new_keys.append((index, self.public_key.child(index)))
yield self.db.add_keys(
self.account, self.chain_number, new_keys
)
defer.returnValue([key[1].address for key in new_keys])
@defer.inlineCallbacks
def get_max_gap(self) -> defer.Deferred:
addresses = yield self._query_addresses(order_by="position ASC")
max_gap = 0
current_gap = 0
for address in addresses:
if address['used_times'] == 0:
current_gap += 1
else:
max_gap = max(max_gap, current_gap)
current_gap = 0
defer.returnValue(max_gap)
@defer.inlineCallbacks
def ensure_address_gap(self) -> defer.Deferred:
addresses = yield self._query_addresses(self.gap, None, "position DESC")
existing_gap = 0
for address in addresses:
if address['used_times'] == 0:
existing_gap += 1
else:
break
if existing_gap == self.gap:
defer.returnValue([])
start = addresses[0]['position']+1 if addresses else 0
end = start + (self.gap - existing_gap)
new_keys = yield self.generate_keys(start, end-1)
defer.returnValue(new_keys)
def get_address_records(self, limit: int = None, only_usable: bool = False):
return self._query_addresses(
limit, self.maximum_uses_per_address if only_usable else None,
"used_times ASC, position ASC"
)
class SingleKey(AddressManager):
""" Single Key address manager always returns the same address for all operations. """
name = "single-address"
__slots__ = ()
@classmethod
def from_dict(cls, account: 'BaseAccount', d: dict)\
-> Tuple[AddressManager, AddressManager]:
same_address_manager = cls(account, account.public_key, 0)
return same_address_manager, same_address_manager
def get_private_key(self, index: int) -> PrivateKey:
return self.account.private_key
def get_max_gap(self) -> defer.Deferred:
return defer.succeed(0)
@defer.inlineCallbacks
def ensure_address_gap(self) -> defer.Deferred:
exists = yield self.get_address_records()
if not exists:
yield self.db.add_keys(
self.account, self.chain_number, [(0, self.public_key)]
)
defer.returnValue([self.public_key.address])
defer.returnValue([])
def get_address_records(self, limit: int = None, only_usable: bool = False) -> defer.Deferred:
return self._query_addresses()
class BaseAccount:
mnemonic_class = Mnemonic
private_key_class = PrivateKey
public_key_class = PubKey
address_generators = {
SingleKey.name: SingleKey,
HierarchicalDeterministic.name: HierarchicalDeterministic,
}
def __init__(self, ledger: 'baseledger.BaseLedger', name: str, seed: str, encrypted: bool,
private_key: PrivateKey, public_key: PubKey, address_generator: dict
) -> None:
self.ledger = ledger
self.name = name
self.seed = seed
self.encrypted = encrypted
self.private_key = private_key
self.public_key = public_key
generator_name = address_generator.get('name', HierarchicalDeterministic.name)
self.address_generator: Type[AddressManager] = self.address_generators[generator_name]
self.receiving, self.change = self.address_generator.from_dict(self, address_generator)
self.address_managers = {self.receiving, self.change}
ledger.add_account(self)
@classmethod
def generate(cls, ledger: 'baseledger.BaseLedger', password: str, address_generator: dict = None):
seed = cls.mnemonic_class().make_seed()
return cls.from_seed(ledger, seed, password, address_generator or {})
@classmethod
def from_seed(cls, ledger: 'baseledger.BaseLedger', seed: str, password: str, address_generator: dict):
private_key = cls.get_private_key_from_seed(ledger, seed, password)
return cls(
ledger=ledger, name='Account #{}'.format(private_key.public_key.address),
seed=seed, encrypted=False,
private_key=private_key,
public_key=private_key.public_key,
address_generator=address_generator
)
@classmethod
def get_private_key_from_seed(cls, ledger: 'baseledger.BaseLedger', seed: str, password: str):
return cls.private_key_class.from_seed(
ledger, cls.mnemonic_class.mnemonic_to_seed(seed, password)
)
@classmethod
def from_dict(cls, ledger: 'baseledger.BaseLedger', d: dict):
if not d['encrypted'] and d['private_key']:
private_key = from_extended_key_string(ledger, d['private_key'])
public_key = private_key.public_key
else:
private_key = d['private_key']
public_key = from_extended_key_string(ledger, d['public_key'])
return cls(
ledger=ledger,
name=d['name'],
seed=d['seed'],
encrypted=d['encrypted'],
private_key=private_key,
public_key=public_key,
address_generator=d['address_generator']
)
def to_dict(self):
private_key = self.private_key
if not self.encrypted and self.private_key:
private_key = self.private_key.extended_key_string()
return {
'ledger': self.ledger.get_id(),
'name': self.name,
'seed': self.seed,
'encrypted': self.encrypted,
'private_key': private_key,
'public_key': self.public_key.extended_key_string(),
'address_generator': self.address_generator.to_dict(self.receiving, self.change)
}
def decrypt(self, password):
assert self.encrypted, "Key is not encrypted."
secret = double_sha256(password)
self.seed = aes_decrypt(secret, self.seed)
self.private_key = from_extended_key_string(self.ledger, aes_decrypt(secret, self.private_key))
self.encrypted = False
def encrypt(self, password):
assert not self.encrypted, "Key is already encrypted."
secret = double_sha256(password)
self.seed = aes_encrypt(secret, self.seed)
self.private_key = aes_encrypt(secret, self.private_key.extended_key_string())
self.encrypted = True
@defer.inlineCallbacks
def ensure_address_gap(self):
addresses = []
for address_manager in self.address_managers:
new_addresses = yield address_manager.ensure_address_gap()
addresses.extend(new_addresses)
defer.returnValue(addresses)
@defer.inlineCallbacks
def get_addresses(self, limit: int = None, max_used_times: int = None) -> defer.Deferred:
records = yield self.get_address_records(limit, max_used_times)
defer.returnValue([r['address'] for r in records])
def get_address_records(self, limit: int = None, max_used_times: int = None) -> defer.Deferred:
return self.ledger.db.get_addresses(self, None, limit, max_used_times)
def get_private_key(self, chain: int, index: int) -> PrivateKey:
assert not self.encrypted, "Cannot get private key on encrypted wallet account."
address_manager = {0: self.receiving, 1: self.change}[chain]
return address_manager.get_private_key(index)
def get_balance(self, confirmations: int = 6, **constraints):
if confirmations > 0:
height = self.ledger.headers.height - (confirmations-1)
constraints.update({'height__lte': height, 'height__gt': 0})
return self.ledger.db.get_balance_for_account(self, **constraints)
@defer.inlineCallbacks
def get_max_gap(self):
change_gap = yield self.change.get_max_gap()
receiving_gap = yield self.receiving.get_max_gap()
defer.returnValue({
'max_change_gap': change_gap,
'max_receiving_gap': receiving_gap,
})
def get_unspent_outputs(self, **constraints):
return self.ledger.db.get_utxos_for_account(self, **constraints)