commit 3eba26b3980719647d826dfb664e39fd51ef0893
parent fc89c8ffa9b1ab4012331447090b36f6f15b13fc
Author: ghost43 <somber.night@protonmail.com>
Date: Tue, 15 Sep 2020 15:37:47 +0000
LN cooperative close: avoid address-reuse (#6590)
Previously if we coop-closed multiple channels in the same session,
they would reuse the wallet address.
Diffstat:
4 files changed, 28 insertions(+), 7 deletions(-)
diff --git a/electrum/lnchannel.py b/electrum/lnchannel.py
@@ -145,7 +145,7 @@ class AbstractChannel(Logger, ABC):
config: Dict[HTLCOwner, Union[LocalConfig, RemoteConfig]]
_sweep_info: Dict[str, Dict[str, 'SweepInfo']]
lnworker: Optional['LNWallet']
- sweep_address: str
+ _fallback_sweep_address: str
channel_id: bytes
funding_outpoint: Outpoint
node_id: bytes
@@ -307,6 +307,20 @@ class AbstractChannel(Logger, ABC):
if self.get_state() == ChannelState.CLOSED and not keep_watching:
self.set_state(ChannelState.REDEEMED)
+ @property
+ def sweep_address(self) -> str:
+ # TODO: in case of unilateral close with pending HTLCs, this address will be reused
+ addr = None
+ if self.is_static_remotekey_enabled():
+ our_payment_pubkey = self.config[LOCAL].payment_basepoint.pubkey
+ addr = make_commitment_output_to_remote_address(our_payment_pubkey)
+ if addr is None:
+ addr = self._fallback_sweep_address
+ assert addr
+ if self.lnworker:
+ assert self.lnworker.wallet.is_mine(addr)
+ return addr
+
@abstractmethod
def is_initiator(self) -> bool:
pass
@@ -367,6 +381,10 @@ class AbstractChannel(Logger, ABC):
"""
pass
+ @abstractmethod
+ def is_static_remotekey_enabled(self) -> bool:
+ pass
+
class ChannelBackup(AbstractChannel):
"""
@@ -383,7 +401,7 @@ class ChannelBackup(AbstractChannel):
Logger.__init__(self)
self.cb = cb
self._sweep_info = {}
- self.sweep_address = sweep_address
+ self._fallback_sweep_address = sweep_address
self.storage = {} # dummy storage
self._state = ChannelState.OPENING
self.config = {}
@@ -485,7 +503,7 @@ class Channel(AbstractChannel):
self.name = name
Logger.__init__(self)
self.lnworker = lnworker
- self.sweep_address = sweep_address
+ self._fallback_sweep_address = sweep_address
self.storage = state
self.db_lock = self.storage.db.lock if self.storage.db else threading.RLock()
self.config = {}
diff --git a/electrum/lnworker.py b/electrum/lnworker.py
@@ -494,7 +494,8 @@ class LNWallet(LNWorker):
self.features |= LnFeatures.OPTION_STATIC_REMOTEKEY_REQ
self.payments = self.db.get_dict('lightning_payments') # RHASH -> amount, direction, is_paid # FIXME amt should be msat
self.preimages = self.db.get_dict('lightning_preimages') # RHASH -> preimage
- self.sweep_address = wallet.get_new_sweep_address_for_channel() # TODO possible address-reuse
+ # note: this sweep_address is only used as fallback; as it might result in address-reuse
+ self.sweep_address = wallet.get_new_sweep_address_for_channel()
self.logs = defaultdict(list) # type: Dict[str, List[PaymentAttemptLog]] # key is RHASH # (not persisted)
self.is_routing = set() # (not persisted) keys of invoices that are in PR_ROUTING state
# used in tests
diff --git a/electrum/tests/test_lnchannel.py b/electrum/tests/test_lnchannel.py
@@ -172,9 +172,8 @@ def create_test_channels(*, feerate=6000, local_msat=None, remote_msat=None,
alice.config[REMOTE].next_per_commitment_point = bob_second
bob.config[REMOTE].next_per_commitment_point = alice_second
- # TODO: sweep_address in lnchannel.py should use static_remotekey
- alice.sweep_address = bitcoin.pubkey_to_address('p2wpkh', alice.config[LOCAL].payment_basepoint.pubkey.hex())
- bob.sweep_address = bitcoin.pubkey_to_address('p2wpkh', bob.config[LOCAL].payment_basepoint.pubkey.hex())
+ alice._fallback_sweep_address = bitcoin.pubkey_to_address('p2wpkh', alice.config[LOCAL].payment_basepoint.pubkey.hex())
+ bob._fallback_sweep_address = bitcoin.pubkey_to_address('p2wpkh', bob.config[LOCAL].payment_basepoint.pubkey.hex())
alice._ignore_max_htlc_value = True
bob._ignore_max_htlc_value = True
diff --git a/electrum/tests/test_lnpeer.py b/electrum/tests/test_lnpeer.py
@@ -103,6 +103,9 @@ class MockWallet:
def is_lightning_backup(self):
return False
+ def is_mine(self, addr):
+ return True
+
class MockLNWallet(Logger, NetworkRetryManager[LNPeerAddr]):
def __init__(self, *, local_keypair: Keypair, chans: Iterable['Channel'], tx_queue):
