commit 740ef0988362648ad78f1845a2ddab9c7909e2de
parent 9abbd077a528d7d602a4d2260a00614a7235432a
Author: ThomasV <thomasv@electrum.org>
Date: Mon, 3 Jun 2019 22:00:44 +0200
simplify_lnsweep
Diffstat:
2 files changed, 65 insertions(+), 106 deletions(-)
diff --git a/electrum/lnsweep.py b/electrum/lnsweep.py
@@ -100,94 +100,47 @@ class ChannelClosedBy(Enum):
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)
+ sweep_info = create_sweeptxs_for_our_ctx(chan, ctx, ctn, chan.sweep_address)
+ if sweep_info:
+ return ChannelClosedBy.US, sweep_info
+ sweep_info = create_sweeptxs_for_their_ctx(chan, ctx, ctn, chan.sweep_address)
+ if sweep_info:
+ return ChannelClosedBy.THEM, sweep_info
+ return ChannelClosedBy.UNKNOWN, {}
- def get_to_local_and_to_remote_addresses_for_our_ctx():
- is_breach = ctn < our_conf.ctn
- # to_local
- our_per_commitment_secret = get_per_commitment_secret_from_seed(
- our_conf.per_commitment_secret_seed, RevocationStore.START_INDEX - ctn)
- our_pcp = ecc.ECPrivkey(our_per_commitment_secret).get_public_key_bytes(compressed=True)
- our_delayed_bp_privkey = ecc.ECPrivkey(our_conf.delayed_basepoint.privkey)
- our_localdelayed_privkey = derive_privkey(our_delayed_bp_privkey.secret_scalar, our_pcp)
- our_localdelayed_privkey = ecc.ECPrivkey.from_secret_scalar(our_localdelayed_privkey)
- their_revocation_pubkey = derive_blinded_pubkey(their_conf.revocation_basepoint.pubkey, our_pcp)
- our_localdelayed_pubkey = our_localdelayed_privkey.get_public_key_bytes(compressed=True)
- to_local_witness_script = bh2u(make_commitment_output_to_local_witness_script(
- their_revocation_pubkey, their_conf.to_self_delay, our_localdelayed_pubkey))
- to_local_address = redeem_script_to_address('p2wsh', to_local_witness_script)
- # to_remote
- their_payment_pubkey = derive_pubkey(their_conf.payment_basepoint.pubkey, our_pcp)
- to_remote_address = make_commitment_output_to_remote_address(their_payment_pubkey)
- return to_local_address, to_remote_address, is_breach
-
- def get_to_local_and_to_remote_addresses_for_their_ctx():
- is_breach = False
- if ctn == their_conf.ctn:
- their_pcp = their_conf.current_per_commitment_point
- elif ctn == their_conf.ctn + 1:
- their_pcp = their_conf.next_per_commitment_point
- elif ctn < their_conf.ctn: # breach
- is_breach = True
- try:
- per_commitment_secret = their_conf.revocation_store.retrieve_secret(RevocationStore.START_INDEX - ctn)
- except UnableToDeriveSecret:
- return None, None, is_breach
- their_pcp = ecc.ECPrivkey(per_commitment_secret).get_public_key_bytes(compressed=True)
- else:
- return None, None, None
- # to_local
- our_revocation_pubkey = derive_blinded_pubkey(our_conf.revocation_basepoint.pubkey, their_pcp)
- their_delayed_pubkey = derive_pubkey(their_conf.delayed_basepoint.pubkey, their_pcp)
- witness_script = bh2u(make_commitment_output_to_local_witness_script(
- our_revocation_pubkey, our_conf.to_self_delay, their_delayed_pubkey))
- to_local_address = redeem_script_to_address('p2wsh', witness_script)
- # to_remote
- our_payment_pubkey = derive_pubkey(our_conf.payment_basepoint.pubkey, their_pcp)
- to_remote_address = make_commitment_output_to_remote_address(our_payment_pubkey)
- return to_local_address, to_remote_address, is_breach
-
- # our ctx?
- 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 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 ChannelClosedBy.THEM
-
- return ChannelClosedBy.UNKNOWN
-
-
-def create_sweeptxs_for_our_ctx(chan: 'Channel', ctx: Transaction,
+
+def create_sweeptxs_for_our_ctx(chan: 'Channel', ctx: Transaction, ctn: int,
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),
but HTLCs cannot (old HTLCs are no longer stored).
"""
- this_conf, other_conf = get_ordered_channel_configs(chan=chan, for_us=True)
- ctn = extract_ctn_from_tx_and_chan(ctx, chan)
+ our_conf, their_conf = get_ordered_channel_configs(chan=chan, for_us=True)
our_per_commitment_secret = get_per_commitment_secret_from_seed(
- this_conf.per_commitment_secret_seed, RevocationStore.START_INDEX - ctn)
+ our_conf.per_commitment_secret_seed, RevocationStore.START_INDEX - ctn)
our_pcp = ecc.ECPrivkey(our_per_commitment_secret).get_public_key_bytes(compressed=True)
- # prep
- this_delayed_bp_privkey = ecc.ECPrivkey(this_conf.delayed_basepoint.privkey)
- our_localdelayed_privkey = derive_privkey(this_delayed_bp_privkey.secret_scalar, our_pcp)
+ our_delayed_bp_privkey = ecc.ECPrivkey(our_conf.delayed_basepoint.privkey)
+ our_localdelayed_privkey = derive_privkey(our_delayed_bp_privkey.secret_scalar, our_pcp)
our_localdelayed_privkey = ecc.ECPrivkey.from_secret_scalar(our_localdelayed_privkey)
- remote_revocation_pubkey = derive_blinded_pubkey(other_conf.revocation_basepoint.pubkey, our_pcp)
- to_self_delay = chan.config[REMOTE].to_self_delay
- this_htlc_privkey = derive_privkey(secret=int.from_bytes(this_conf.htlc_basepoint.privkey, 'big'),
+ their_revocation_pubkey = derive_blinded_pubkey(their_conf.revocation_basepoint.pubkey, our_pcp)
+ to_self_delay = their_conf.to_self_delay
+ our_htlc_privkey = derive_privkey(secret=int.from_bytes(our_conf.htlc_basepoint.privkey, 'big'),
per_commitment_point=our_pcp).to_bytes(32, 'big')
- txs = {}
- # to_local
our_localdelayed_pubkey = our_localdelayed_privkey.get_public_key_bytes(compressed=True)
to_local_witness_script = bh2u(make_commitment_output_to_local_witness_script(
- remote_revocation_pubkey, to_self_delay, our_localdelayed_pubkey))
+ their_revocation_pubkey, to_self_delay, our_localdelayed_pubkey))
to_local_address = redeem_script_to_address('p2wsh', to_local_witness_script)
+ their_payment_pubkey = derive_pubkey(their_conf.payment_basepoint.pubkey, our_pcp)
+ to_remote_address = make_commitment_output_to_remote_address(their_payment_pubkey)
+
+ # test ctx
+ if ctx.get_output_idx_from_address(to_local_address) is None\
+ and ctx.get_output_idx_from_address(to_remote_address) is None:
+ return
+
+ txs = {}
+ # to_local
output_idx = ctx.get_output_idx_from_address(to_local_address)
if output_idx is not None:
sweep_tx = lambda: create_sweeptx_ctx_to_local(
@@ -215,7 +168,7 @@ def create_sweeptxs_for_our_ctx(chan: 'Channel', ctx: Transaction,
our_pcp=our_pcp,
ctx=ctx,
htlc=htlc,
- local_htlc_privkey=this_htlc_privkey,
+ local_htlc_privkey=our_htlc_privkey,
preimage=preimage,
is_received_htlc=is_received_htlc)
sweep_tx = lambda: create_sweeptx_that_spends_htlctx_that_spends_htlc_in_ctx(
@@ -240,47 +193,56 @@ def create_sweeptxs_for_our_ctx(chan: 'Channel', ctx: Transaction,
return txs
-def create_sweeptxs_for_their_ctx(chan: 'Channel', ctx: Transaction,
+def create_sweeptxs_for_their_ctx(chan: 'Channel', ctx: Transaction, ctn: int,
sweep_address: str) -> Dict[str,Transaction]:
"""Handle the case when the remote force-closes with their ctx.
Sweep outputs that do not have a CSV delay ('to_remote' and first-stage HTLCs).
Outputs with CSV delay ('to_local' and second-stage HTLCs) are redeemed by LNWatcher.
"""
- this_conf, other_conf = get_ordered_channel_configs(chan=chan, for_us=False)
+ our_conf, their_conf = get_ordered_channel_configs(chan=chan, for_us=True)
ctn = extract_ctn_from_tx_and_chan(ctx, chan)
# note: the remote sometimes has two valid non-revoked commitment transactions,
- # either of which could be broadcast (this_conf.ctn, this_conf.ctn+1)
+ # either of which could be broadcast (their_conf.ctn, their_conf.ctn+1)
per_commitment_secret = None
- if ctn == this_conf.ctn:
- their_pcp = this_conf.current_per_commitment_point
+ if ctn == their_conf.ctn:
+ their_pcp = their_conf.current_per_commitment_point
is_revocation = False
- elif ctn == this_conf.ctn + 1:
- their_pcp = this_conf.next_per_commitment_point
+ elif ctn == their_conf.ctn + 1:
+ their_pcp = their_conf.next_per_commitment_point
is_revocation = False
- elif ctn < this_conf.ctn: # breach
+ elif ctn < their_conf.ctn: # breach
try:
- per_commitment_secret = this_conf.revocation_store.retrieve_secret(RevocationStore.START_INDEX - ctn)
+ per_commitment_secret = their_conf.revocation_store.retrieve_secret(RevocationStore.START_INDEX - ctn)
except UnableToDeriveSecret:
- return {}
+ return
their_pcp = ecc.ECPrivkey(per_commitment_secret).get_public_key_bytes(compressed=True)
is_revocation = True
- other_revocation_privkey = derive_blinded_privkey(other_conf.revocation_basepoint.privkey, per_commitment_secret)
+ our_revocation_privkey = derive_blinded_privkey(our_conf.revocation_basepoint.privkey, per_commitment_secret)
else:
- return {}
+ return
+ # to_local and to_remote addresses
+ our_revocation_pubkey = derive_blinded_pubkey(our_conf.revocation_basepoint.pubkey, their_pcp)
+ their_delayed_pubkey = derive_pubkey(their_conf.delayed_basepoint.pubkey, their_pcp)
+ witness_script = bh2u(make_commitment_output_to_local_witness_script(
+ our_revocation_pubkey, our_conf.to_self_delay, their_delayed_pubkey))
+ to_local_address = redeem_script_to_address('p2wsh', witness_script)
+ our_payment_pubkey = derive_pubkey(our_conf.payment_basepoint.pubkey, their_pcp)
+ to_remote_address = make_commitment_output_to_remote_address(our_payment_pubkey)
+ # test ctx
+ if ctx.get_output_idx_from_address(to_local_address) is None \
+ and ctx.get_output_idx_from_address(to_remote_address) is None:
+ return
# prep
- other_revocation_pubkey = derive_blinded_pubkey(other_conf.revocation_basepoint.pubkey, their_pcp)
- other_htlc_privkey = derive_privkey(secret=int.from_bytes(other_conf.htlc_basepoint.privkey, 'big'), per_commitment_point=their_pcp)
- other_htlc_privkey = ecc.ECPrivkey.from_secret_scalar(other_htlc_privkey)
- this_htlc_pubkey = derive_pubkey(this_conf.htlc_basepoint.pubkey, their_pcp)
- other_payment_bp_privkey = ecc.ECPrivkey(other_conf.payment_basepoint.privkey)
- other_payment_privkey = derive_privkey(other_payment_bp_privkey.secret_scalar, their_pcp)
- other_payment_privkey = ecc.ECPrivkey.from_secret_scalar(other_payment_privkey)
-
+ our_htlc_privkey = derive_privkey(secret=int.from_bytes(our_conf.htlc_basepoint.privkey, 'big'), per_commitment_point=their_pcp)
+ our_htlc_privkey = ecc.ECPrivkey.from_secret_scalar(our_htlc_privkey)
+ their_htlc_pubkey = derive_pubkey(their_conf.htlc_basepoint.pubkey, their_pcp)
+ our_payment_bp_privkey = ecc.ECPrivkey(our_conf.payment_basepoint.privkey)
+ our_payment_privkey = derive_privkey(our_payment_bp_privkey.secret_scalar, their_pcp)
+ our_payment_privkey = ecc.ECPrivkey.from_secret_scalar(our_payment_privkey)
+ assert our_payment_pubkey == our_payment_privkey.get_public_key_bytes(compressed=True)
txs = {}
# to_local is handled by lnwatcher
# to_remote
- our_payment_pubkey = other_payment_privkey.get_public_key_bytes(compressed=True)
- to_remote_address = make_commitment_output_to_remote_address(our_payment_pubkey)
output_idx = ctx.get_output_idx_from_address(to_remote_address)
if output_idx is not None:
prevout = ctx.txid() + ':%d'%output_idx
@@ -288,7 +250,7 @@ def create_sweeptxs_for_their_ctx(chan: 'Channel', ctx: Transaction,
sweep_address=sweep_address,
ctx=ctx,
output_idx=output_idx,
- our_payment_privkey=other_payment_privkey)
+ our_payment_privkey=our_payment_privkey)
txs[prevout] = ('their_ctx_to_remote', 0, 0, sweep_tx)
# HTLCs
def create_sweeptx_for_htlc(htlc: 'UpdateAddHtlc', is_received_htlc: bool) -> Optional[Transaction]:
@@ -302,9 +264,9 @@ def create_sweeptxs_for_their_ctx(chan: 'Channel', ctx: Transaction,
preimage = None
htlc_output_witness_script = make_htlc_output_witness_script(
is_received_htlc=is_received_htlc,
- remote_revocation_pubkey=other_revocation_pubkey,
- remote_htlc_pubkey=other_htlc_privkey.get_public_key_bytes(compressed=True),
- local_htlc_pubkey=this_htlc_pubkey,
+ remote_revocation_pubkey=our_revocation_pubkey,
+ remote_htlc_pubkey=our_htlc_privkey.get_public_key_bytes(compressed=True),
+ local_htlc_pubkey=their_htlc_pubkey,
payment_hash=htlc.payment_hash,
cltv_expiry=htlc.cltv_expiry)
htlc_address = redeem_script_to_address('p2wsh', bh2u(htlc_output_witness_script))
@@ -320,7 +282,7 @@ def create_sweeptxs_for_their_ctx(chan: 'Channel', ctx: Transaction,
sweep_address=sweep_address,
preimage=preimage,
output_idx=output_idx,
- privkey=other_revocation_privkey if is_revocation else other_htlc_privkey.get_secret_bytes(),
+ privkey=our_revocation_privkey if is_revocation else our_htlc_privkey.get_secret_bytes(),
is_revocation=is_revocation,
cltv_expiry=cltv_expiry)
name = f'their_ctx_sweep_htlc_{ctx.txid()[:8]}_{output_idx}'
diff --git a/electrum/lnworker.py b/electrum/lnworker.py
@@ -516,16 +516,13 @@ class LNWallet(LNWorker):
# detect who closed and set sweep_info
if chan.sweep_info is None:
- closed_by = lnsweep.detect_who_closed(chan, closing_tx)
+ closed_by, chan.sweep_info = 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
