commit 6bbdbf75961dbda5bac4566c3447e4d7d5beccaa
parent 930d21c31c5240fe57ed5f53335637e4f3ac5335
Author: ThomasV <thomasv@electrum.org>
Date: Sat, 25 May 2019 06:02:23 +0200
rework on_channel_closed in LNWorker:
- use detect_who_closed; this allows us to redeem to_remote of breach ctx
- do not redeem to_local of breach ctx, because it is redundant with lnwatcher
- rename a few methods
Diffstat:
3 files changed, 33 insertions(+), 51 deletions(-)
diff --git a/electrum/lnchannel.py b/electrum/lnchannel.py
@@ -46,8 +46,7 @@ from .lnutil import (Outpoint, LocalConfig, RemoteConfig, Keypair, OnlyPubkeyKey
HTLC_TIMEOUT_WEIGHT, HTLC_SUCCESS_WEIGHT, extract_ctn_from_tx_and_chan, UpdateAddHtlc,
funding_output_script, SENT, RECEIVED, LOCAL, REMOTE, HTLCOwner, make_commitment_outputs,
ScriptHtlc, PaymentFailure, calc_onchain_fees, RemoteMisbehaving, make_htlc_output_witness_script)
-from .lnsweep import create_sweeptxs_for_their_just_revoked_ctx
-from .lnsweep import create_sweeptxs_for_our_latest_ctx, create_sweeptxs_for_their_latest_ctx
+from .lnsweep import create_sweeptxs_for_their_revoked_ctx
from .lnhtlc import HTLCManager
@@ -168,6 +167,7 @@ class Channel(Logger):
self.local_commitment = None
self.remote_commitment = None
+ self.sweep_info = None
def get_payments(self):
out = {}
@@ -186,13 +186,9 @@ class Channel(Logger):
ctn = extract_ctn_from_tx_and_chan(ctx, self)
assert self.signature_fits(ctx), (self.hm.log[LOCAL])
self.local_commitment = ctx
- if self.sweep_address is not None:
- self.local_sweeptxs = create_sweeptxs_for_our_latest_ctx(self, self.local_commitment, self.sweep_address)
def set_remote_commitment(self):
self.remote_commitment = self.current_commitment(REMOTE)
- if self.sweep_address is not None:
- self.remote_sweeptxs = create_sweeptxs_for_their_latest_ctx(self, self.remote_commitment, self.sweep_address)
def open_with_first_pcp(self, remote_pcp, remote_sig):
self.remote_commitment_to_be_revoked = self.pending_commitment(REMOTE)
@@ -460,7 +456,7 @@ class Channel(Logger):
return
outpoint = self.funding_outpoint.to_str()
ctx = self.remote_commitment_to_be_revoked # FIXME can't we just reconstruct it?
- sweeptxs = create_sweeptxs_for_their_just_revoked_ctx(self, ctx, per_commitment_secret, self.sweep_address)
+ sweeptxs = create_sweeptxs_for_their_revoked_ctx(self, ctx, per_commitment_secret, self.sweep_address)
for prev_txid, tx in sweeptxs.items():
if tx is not None:
self.lnwatcher.add_sweep_tx(outpoint, prev_txid, str(tx))
diff --git a/electrum/lnsweep.py b/electrum/lnsweep.py
@@ -56,8 +56,8 @@ def maybe_create_sweeptx_for_their_ctx_to_local(ctx: Transaction, revocation_pri
return sweep_tx
-def create_sweeptxs_for_their_just_revoked_ctx(chan: 'Channel', ctx: Transaction, per_commitment_secret: bytes,
- sweep_address: str) -> Dict[str,Transaction]:
+def create_sweeptxs_for_their_revoked_ctx(chan: 'Channel', ctx: Transaction, per_commitment_secret: bytes,
+ sweep_address: str) -> Dict[str,Transaction]:
"""Presign sweeping transactions using the just received revoked pcs.
These will only be utilised if the remote breaches.
Sweep 'to_local', and all the HTLCs (two cases: directly from ctx, or from HTLC tx).
@@ -135,12 +135,8 @@ class ChannelClosedBy(Enum):
UNKNOWN = auto()
-class ChannelCloseSituationReport(NamedTuple):
- closed_by: ChannelClosedBy
- is_breach: Optional[bool]
-
-def detect_how_channel_was_closed(chan: 'Channel', ctx: Transaction) -> ChannelCloseSituationReport:
+def detect_who_closed(chan: 'Channel', ctx: Transaction) -> ChannelClosedBy:
ctn = extract_ctn_from_tx_and_chan(ctx, chan)
our_conf, their_conf = get_ordered_channel_configs(chan=chan, for_us=True)
@@ -193,19 +189,19 @@ def detect_how_channel_was_closed(chan: 'Channel', ctx: Transaction) -> ChannelC
to_local_address, to_remote_address, is_breach = get_to_local_and_to_remote_addresses_for_our_ctx()
if (to_local_address and ctx.get_output_idx_from_address(to_local_address) is not None
or to_remote_address and ctx.get_output_idx_from_address(to_remote_address) is not None):
- return ChannelCloseSituationReport(closed_by=ChannelClosedBy.US, is_breach=is_breach)
+ return ChannelClosedBy.US
# their ctx?
to_local_address, to_remote_address, is_breach = get_to_local_and_to_remote_addresses_for_their_ctx()
if (to_local_address and ctx.get_output_idx_from_address(to_local_address) is not None
or to_remote_address and ctx.get_output_idx_from_address(to_remote_address) is not None):
- return ChannelCloseSituationReport(closed_by=ChannelClosedBy.THEM, is_breach=is_breach)
+ return ChannelClosedBy.THEM
- return ChannelCloseSituationReport(closed_by=ChannelClosedBy.UNKNOWN, is_breach=None)
+ return ChannelClosedBy.UNKNOWN
-def create_sweeptxs_for_our_latest_ctx(chan: 'Channel', ctx: Transaction,
- sweep_address: str) -> Dict[str,Transaction]:
+def create_sweeptxs_for_our_ctx(chan: 'Channel', ctx: Transaction,
+ sweep_address: str) -> Dict[str,Transaction]:
"""Handle the case where we force close unilaterally with our latest ctx.
Construct sweep txns for 'to_local', and for all HTLCs (2 txns each).
'to_local' can be swept even if this is a breach (by us),
@@ -277,8 +273,8 @@ def create_sweeptxs_for_our_latest_ctx(chan: 'Channel', ctx: Transaction,
return txs
-def create_sweeptxs_for_their_latest_ctx(chan: 'Channel', ctx: Transaction,
- sweep_address: str) -> Dict[str,Transaction]:
+def create_sweeptxs_for_their_ctx(chan: 'Channel', ctx: Transaction,
+ sweep_address: str) -> Dict[str,Transaction]:
"""Handle the case when the remote force-closes with their ctx.
Regardless of it is a breach or not, construct sweep tx for 'to_remote'.
If it is a breach, also construct sweep tx for 'to_local'.
@@ -313,18 +309,7 @@ def create_sweeptxs_for_their_latest_ctx(chan: 'Channel', ctx: Transaction,
other_payment_privkey = ecc.ECPrivkey.from_secret_scalar(other_payment_privkey)
txs = {}
- if per_commitment_secret: # breach
- # to_local
- other_revocation_privkey = derive_blinded_privkey(other_conf.revocation_basepoint.privkey,
- per_commitment_secret)
- this_delayed_pubkey = derive_pubkey(this_conf.delayed_basepoint.pubkey, their_pcp)
- sweep_tx = maybe_create_sweeptx_for_their_ctx_to_local(ctx=ctx,
- revocation_privkey=other_revocation_privkey,
- to_self_delay=other_conf.to_self_delay,
- delayed_pubkey=this_delayed_pubkey,
- sweep_address=sweep_address)
- if sweep_tx:
- txs[sweep_tx.prevout(0)] = sweep_tx
+ # to_local is handled by lnwatcher
# to_remote
sweep_tx = maybe_create_sweeptx_for_their_ctx_to_remote(ctx=ctx,
sweep_address=sweep_address,
diff --git a/electrum/lnworker.py b/electrum/lnworker.py
@@ -46,6 +46,7 @@ from .lnrouter import RouteEdge, is_route_sane_to_use
from .address_synchronizer import TX_HEIGHT_LOCAL
from . import lnsweep
from .lnsweep import ChannelClosedBy
+from .lnsweep import create_sweeptxs_for_their_ctx, create_sweeptxs_for_our_ctx
if TYPE_CHECKING:
from .network import Network
@@ -511,24 +512,24 @@ class LNWallet(LNWorker):
# remove from channel_db
if chan.short_channel_id is not None:
self.channel_db.remove_channel(chan.short_channel_id)
- # detect who closed
- assert closing_tx, f"no closing tx... {repr(closing_tx)}"
- sitrep = lnsweep.detect_how_channel_was_closed(chan, closing_tx)
- if sitrep.closed_by == ChannelClosedBy.US:
- self.logger.info(f'we force closed {funding_outpoint}. sitrep: {repr(sitrep)}')
- encumbered_sweeptxs = chan.local_sweeptxs
- elif sitrep.closed_by == ChannelClosedBy.THEM and sitrep.is_breach is False:
- self.logger.info(f'they force closed {funding_outpoint}. sitrep: {repr(sitrep)}')
- encumbered_sweeptxs = chan.remote_sweeptxs
- else:
- self.logger.info(f'not sure who closed {funding_outpoint} {closing_txid}. sitrep: {repr(sitrep)}')
- return
- # sweep
- for prevout, spender in spenders.items():
- e_tx = encumbered_sweeptxs.get(prevout)
- if e_tx is None:
- continue
- if spender is not None:
+
+ # detect who closed and set sweep_info
+ if chan.sweep_info is None:
+ closed_by = lnsweep.detect_who_closed(chan, closing_tx)
+ if closed_by == ChannelClosedBy.US:
+ self.logger.info(f'we force closed {funding_outpoint}.')
+ chan.sweep_info = create_sweeptxs_for_our_ctx(chan, closing_tx, chan.sweep_address)
+ elif closed_by == ChannelClosedBy.THEM:
+ self.logger.info(f'they force closed {funding_outpoint}.')
+ chan.sweep_info = create_sweeptxs_for_their_ctx(chan, closing_tx, chan.sweep_address)
+ else:
+ self.logger.info(f'not sure who closed {funding_outpoint} {closing_txid}.')
+ chan.sweep_info = {}
+ self.logger.info(f'{repr(chan.sweep_info)}')
+
+ # create and broadcast transaction
+ for prevout, e_tx in chan.sweep_info.items():
+ if spenders.get(prevout) is not None:
self.logger.info(f'outpoint already spent {prevout}')
continue
prev_txid, prev_index = prevout.split(':')
