lbry-sdk/torba/client/baseaccount.py
2019-03-11 22:50:39 -04:00

433 lines
17 KiB
Python

import json
import asyncio
import random
import typing
from typing import Dict, Tuple, Type, Optional, Any, List
from torba.client.mnemonic import Mnemonic
from torba.client.bip32 import PrivateKey, PubKey, from_extended_key_string
from torba.client.hash import aes_encrypt, aes_decrypt, sha256
from torba.client.constants import COIN
if typing.TYPE_CHECKING:
from torba.client import baseledger, wallet as basewallet
class AddressManager:
name: str
__slots__ = 'account', 'public_key', 'chain_number', 'address_generator_lock'
def __init__(self, account, public_key, chain_number):
self.account = account
self.public_key = public_key
self.chain_number = chain_number
self.address_generator_lock = asyncio.Lock()
@classmethod
def from_dict(cls, account: 'BaseAccount', d: dict) \
-> Tuple['AddressManager', 'AddressManager']:
raise NotImplementedError
@classmethod
def to_dict(cls, receiving: 'AddressManager', change: 'AddressManager') -> Dict:
d: Dict[str, Any] = {'name': cls.name}
receiving_dict = receiving.to_dict_instance()
if receiving_dict:
d['receiving'] = receiving_dict
change_dict = change.to_dict_instance()
if change_dict:
d['change'] = change_dict
return d
def to_dict_instance(self) -> Optional[dict]:
raise NotImplementedError
def _query_addresses(self, **constraints):
return self.account.ledger.db.get_addresses(
account=self.account,
chain=self.chain_number,
**constraints
)
def get_private_key(self, index: int) -> PrivateKey:
raise NotImplementedError
async def get_max_gap(self):
raise NotImplementedError
async def ensure_address_gap(self):
raise NotImplementedError
def get_address_records(self, only_usable: bool = False, **constraints):
raise NotImplementedError
async def get_addresses(self, only_usable: bool = False, **constraints) -> List[str]:
records = await self.get_address_records(only_usable=only_usable, **constraints)
return [r['address'] for r in records]
async def get_or_create_usable_address(self) -> str:
addresses = await self.get_addresses(only_usable=True, limit=10)
if addresses:
return random.choice(addresses)
addresses = await self.ensure_address_gap()
return 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': 1})),
cls(account, 1, **d.get('change', {'gap': 6, 'maximum_uses_per_address': 1}))
)
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)
async def get_max_gap(self) -> int:
addresses = await 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
return max_gap
async def ensure_address_gap(self) -> List[str]:
async with self.address_generator_lock:
addresses = await self._query_addresses(limit=self.gap, order_by="position DESC")
existing_gap = 0
for address in addresses:
if address['used_times'] == 0:
existing_gap += 1
else:
break
if existing_gap == self.gap:
return []
start = addresses[0]['position']+1 if addresses else 0
end = start + (self.gap - existing_gap)
new_keys = await self._generate_keys(start, end-1)
await self.account.ledger.announce_addresses(self, new_keys)
return new_keys
async def _generate_keys(self, start: int, end: int) -> List[str]:
if not self.address_generator_lock.locked():
raise RuntimeError('Should not be called outside of address_generator_lock.')
keys = [(index, self.public_key.child(index)) for index in range(start, end+1)]
await self.account.ledger.db.add_keys(self.account, self.chain_number, keys)
return [key[1].address for key in keys]
def get_address_records(self, only_usable: bool = False, **constraints):
if only_usable:
constraints['used_times__lt'] = self.maximum_uses_per_address
if 'order_by' not in constraints:
constraints['order_by'] = "used_times ASC, position ASC"
return self._query_addresses(**constraints)
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 to_dict_instance(self):
return None
def get_private_key(self, index: int) -> PrivateKey:
return self.account.private_key
async def get_max_gap(self) -> int:
return 0
async def ensure_address_gap(self) -> List[str]:
async with self.address_generator_lock:
exists = await self.get_address_records()
if not exists:
await self.account.ledger.db.add_keys(
self.account, self.chain_number, [(0, self.public_key)]
)
new_keys = [self.public_key.address]
await self.account.ledger.announce_addresses(self, new_keys)
return new_keys
return []
def get_address_records(self, only_usable: bool = False, **constraints):
return self._query_addresses(**constraints)
class BaseAccount:
mnemonic_class = Mnemonic
private_key_class = PrivateKey
public_key_class = PubKey
address_generators: Dict[str, Type[AddressManager]] = {
SingleKey.name: SingleKey,
HierarchicalDeterministic.name: HierarchicalDeterministic,
}
def __init__(self, ledger: 'baseledger.BaseLedger', wallet: 'basewallet.Wallet', name: str,
seed: str, private_key_string: str, encrypted: bool,
private_key: Optional[PrivateKey], public_key: PubKey,
address_generator: dict) -> None:
self.ledger = ledger
self.wallet = wallet
self.id = public_key.address
self.name = name
self.seed = seed
self.private_key_string = private_key_string
self.password: Optional[str] = None
self.private_key_encryption_init_vector: Optional[bytes] = None
self.seed_encryption_init_vector: Optional[bytes] = None
self.encrypted = encrypted
self.serialize_encrypted = encrypted
self.private_key = private_key
self.public_key = public_key
generator_name = address_generator.get('name', HierarchicalDeterministic.name)
self.address_generator = self.address_generators[generator_name]
self.receiving, self.change = self.address_generator.from_dict(self, address_generator)
self.address_managers = {am.chain_number: am for am in {self.receiving, self.change}}
ledger.add_account(self)
wallet.add_account(self)
@classmethod
def generate(cls, ledger: 'baseledger.BaseLedger', wallet: 'basewallet.Wallet',
name: str = None, address_generator: dict = None):
return cls.from_dict(ledger, wallet, {
'name': name,
'seed': cls.mnemonic_class().make_seed(),
'address_generator': address_generator or {}
})
@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 keys_from_dict(cls, ledger: 'baseledger.BaseLedger', d: dict) \
-> Tuple[str, Optional[PrivateKey], PubKey]:
seed = d.get('seed', '')
private_key_string = d.get('private_key', '')
private_key = None
public_key = None
encrypted = d.get('encrypted', False)
if not encrypted:
if seed:
private_key = cls.get_private_key_from_seed(ledger, seed, '')
public_key = private_key.public_key
elif private_key:
private_key = from_extended_key_string(ledger, private_key_string)
public_key = private_key.public_key
if public_key is None:
public_key = from_extended_key_string(ledger, d['public_key'])
return seed, private_key, public_key
@classmethod
def from_dict(cls, ledger: 'baseledger.BaseLedger', wallet: 'basewallet.Wallet', d: dict):
seed, private_key, public_key = cls.keys_from_dict(ledger, d)
name = d.get('name')
if not name:
name = 'Account #{}'.format(public_key.address)
return cls(
ledger=ledger,
wallet=wallet,
name=name,
seed=seed,
private_key_string=d.get('private_key', ''),
encrypted=d.get('encrypted', False),
private_key=private_key,
public_key=public_key,
address_generator=d.get('address_generator', {})
)
def to_dict(self):
private_key_string, seed = self.private_key_string, self.seed
if not self.encrypted and self.private_key:
private_key_string = self.private_key.extended_key_string()
if not self.encrypted and self.serialize_encrypted:
assert None not in [self.seed_encryption_init_vector, self.private_key_encryption_init_vector]
private_key_string = aes_encrypt(
self.password, private_key_string, self.private_key_encryption_init_vector
)[0]
seed = aes_encrypt(self.password, self.seed, self.seed_encryption_init_vector)[0]
return {
'ledger': self.ledger.get_id(),
'name': self.name,
'seed': seed,
'encrypted': self.serialize_encrypted,
'private_key': private_key_string,
'public_key': self.public_key.extended_key_string(),
'address_generator': self.address_generator.to_dict(self.receiving, self.change)
}
@property
def hash(self) -> bytes:
return sha256(json.dumps(self.to_dict()).encode())
async def get_details(self, show_seed=False, **kwargs):
satoshis = await self.get_balance(**kwargs)
details = {
'id': self.id,
'name': self.name,
'coins': round(satoshis/COIN, 2),
'satoshis': satoshis,
'encrypted': self.encrypted,
'public_key': self.public_key.extended_key_string(),
'address_generator': self.address_generator.to_dict(self.receiving, self.change)
}
if show_seed:
details['seed'] = self.seed
return details
def decrypt(self, password: str) -> None:
assert self.encrypted, "Key is not encrypted."
try:
seed, seed_iv = aes_decrypt(password, self.seed)
pk_string, pk_iv = aes_decrypt(password, self.private_key_string)
except ValueError: # failed to remove padding, password is wrong
return
try:
Mnemonic().mnemonic_decode(seed)
except IndexError: # failed to decode the seed, this either means it decrypted and is invalid
# or that we hit an edge case where an incorrect password gave valid padding
return
try:
private_key = from_extended_key_string(
self.ledger, pk_string
)
except (TypeError, ValueError):
return
self.seed = seed
self.seed_encryption_init_vector = seed_iv
self.private_key = private_key
self.private_key_encryption_init_vector = pk_iv
self.password = password
self.encrypted = False
def encrypt(self, password: str) -> None:
assert not self.encrypted, "Key is already encrypted."
assert isinstance(self.private_key, PrivateKey)
self.seed = aes_encrypt(password, self.seed, self.seed_encryption_init_vector)[0]
self.private_key_string = aes_encrypt(
password, self.private_key.extended_key_string(), self.private_key_encryption_init_vector
)[0]
self.private_key = None
self.password = None
self.encrypted = True
async def ensure_address_gap(self):
addresses = []
for address_manager in self.address_managers.values():
new_addresses = await address_manager.ensure_address_gap()
addresses.extend(new_addresses)
return addresses
async def get_addresses(self, **constraints) -> List[str]:
rows = await self.ledger.db.select_addresses('address', account=self, **constraints)
return [r[0] for r in rows]
def get_address_records(self, **constraints):
return self.ledger.db.get_addresses(account=self, **constraints)
def get_address_count(self, **constraints):
return self.ledger.db.get_address_count(account=self, **constraints)
def get_private_key(self, chain: int, index: int) -> PrivateKey:
assert not self.encrypted, "Cannot get private key on encrypted wallet account."
return self.address_managers[chain].get_private_key(index)
def get_balance(self, confirmations: int = 0, **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(account=self, **constraints)
async def get_max_gap(self):
change_gap = await self.change.get_max_gap()
receiving_gap = await self.receiving.get_max_gap()
return {
'max_change_gap': change_gap,
'max_receiving_gap': receiving_gap,
}
def get_utxos(self, **constraints):
return self.ledger.db.get_utxos(account=self, **constraints)
def get_utxo_count(self, **constraints):
return self.ledger.db.get_utxo_count(account=self, **constraints)
def get_transactions(self, **constraints):
return self.ledger.db.get_transactions(account=self, **constraints)
def get_transaction_count(self, **constraints):
return self.ledger.db.get_transaction_count(account=self, **constraints)
async def fund(self, to_account, amount=None, everything=False,
outputs=1, broadcast=False, **constraints):
assert self.ledger == to_account.ledger, 'Can only transfer between accounts of the same ledger.'
tx_class = self.ledger.transaction_class
if everything:
utxos = await self.get_utxos(**constraints)
await self.ledger.reserve_outputs(utxos)
tx = await tx_class.create(
inputs=[tx_class.input_class.spend(txo) for txo in utxos],
outputs=[],
funding_accounts=[self],
change_account=to_account
)
elif amount > 0:
to_address = await to_account.change.get_or_create_usable_address()
to_hash160 = to_account.ledger.address_to_hash160(to_address)
tx = await tx_class.create(
inputs=[],
outputs=[
tx_class.output_class.pay_pubkey_hash(amount//outputs, to_hash160)
for _ in range(outputs)
],
funding_accounts=[self],
change_account=self
)
else:
raise ValueError('An amount is required.')
if broadcast:
await self.ledger.broadcast(tx)
else:
await self.ledger.release_outputs(
[txi.txo_ref.txo for txi in tx.inputs]
)
return tx