AaronFiore/electrum
1
0
Fork 0
Code Activity

ln: remove unneeded forwarding htlc features, check commitment sig using lnhtlc while receiving

Browse Source
This commit is contained in:
Janus
2018-06-11 19:53:15 +02:00
committed by ThomasV
parent 4d25933898
commit bd0f659f26
4 changed files with 92 additions and 95 deletions
Download Patch File Download Diff File Expand all files Collapse all files

69
lib/lnbase.py
View File

@@ -490,17 +490,23 @@ def make_commitment_using_open_channel(chan, ctn, for_us, pcp, local_msat, remot
remote_msat,
chan.local_config.dust_limit_sat,
chan.constraints.feerate,
for_us, htlcs=htlcs)
for_us,
chan.constraints.is_initiator,
htlcs=htlcs)
def make_commitment(ctn, local_funding_pubkey, remote_funding_pubkey, remote_payment_pubkey,
payment_basepoint, remote_payment_basepoint,
revocation_pubkey, delayed_pubkey, to_self_delay,
funding_txid, funding_pos, funding_sat,
local_amount, remote_amount,
dust_limit_sat, local_feerate, for_us, htlcs):
def make_commitment(ctn, local_funding_pubkey, remote_funding_pubkey,
remote_payment_pubkey, payment_basepoint,
remote_payment_basepoint, revocation_pubkey,
delayed_pubkey, to_self_delay, funding_txid,
funding_pos, funding_sat, local_amount, remote_amount,
dust_limit_sat, local_feerate, for_us, we_are_initiator,
htlcs):
pubkeys = sorted([bh2u(local_funding_pubkey), bh2u(remote_funding_pubkey)])
obs = get_obscured_ctn(ctn, payment_basepoint, remote_payment_basepoint)
payments = [payment_basepoint, remote_payment_basepoint]
if not we_are_initiator:
payments.reverse()
obs = get_obscured_ctn(ctn, *payments)
locktime = (0x20 << 24) + (obs & 0xffffff)
sequence = (0x80 << 24) + (obs >> 24)
print_error('locktime', locktime, hex(locktime))
@@ -524,10 +530,11 @@ def make_commitment(ctn, local_funding_pubkey, remote_funding_pubkey, remote_pay
# TODO trim htlc outputs here while also considering 2nd stage htlc transactions
fee = local_feerate * overall_weight(len(htlcs)) # TODO incorrect if anything is trimmed
assert type(fee) is int
to_local_amt = local_amount - (fee if for_us else 0)
we_pay_fee = for_us == we_are_initiator
to_local_amt = local_amount - (fee if we_pay_fee else 0)
assert type(to_local_amt) is int
to_local = (bitcoin.TYPE_ADDRESS, local_address, to_local_amt // 1000)
to_remote_amt = remote_amount - (fee if not for_us else 0)
to_remote_amt = remote_amount - (fee if not we_pay_fee else 0)
assert type(to_remote_amt) is int
to_remote = (bitcoin.TYPE_ADDRESS, remote_address, to_remote_amt // 1000)
c_outputs = [to_local, to_remote]
@@ -878,7 +885,7 @@ class Peer(PrintError):
local_config.payment_basepoint.pubkey, remote_config.payment_basepoint.pubkey,
revocation_pubkey, remote_delayedpubkey, local_config.to_self_delay,
funding_txid, funding_index, funding_sat,
remote_amount, local_amount, remote_config.dust_limit_sat, local_feerate, False, htlcs=[])
remote_amount, local_amount, remote_config.dust_limit_sat, local_feerate, False, we_are_initiator=True, htlcs=[])
sig_64 = sign_and_get_sig_string(remote_ctx, local_config, remote_config)
channel_id, funding_txid_bytes = channel_id_from_funding_tx(funding_txid, funding_index)
self.send_message(gen_msg("funding_created",
@@ -896,7 +903,7 @@ class Peer(PrintError):
local_config.payment_basepoint.pubkey, remote_config.payment_basepoint.pubkey,
remote_revocation_pubkey, local_delayedpubkey, remote_config.to_self_delay,
funding_txid, funding_index, funding_sat,
local_amount, remote_amount, local_config.dust_limit_sat, local_feerate, True, htlcs=[])
local_amount, remote_amount, local_config.dust_limit_sat, local_feerate, True, we_are_initiator=True, htlcs=[])
pre_hash = bitcoin.Hash(bfh(local_ctx.serialize_preimage(0)))
if not ecc.verify_signature(remote_config.multisig_key.pubkey, remote_sig, pre_hash):
raise Exception('verifying remote signature failed.')
@@ -1045,7 +1052,7 @@ class Peer(PrintError):
m.add_htlc(htlc)
sig_64, htlc_sigs = m.sign_next_commitment()
htlc_sig = htlc_sigs[0][1]
htlc_sig = htlc_sigs[0]
self.send_message(gen_msg("commitment_signed", channel_id=chan.channel_id, signature=sig_64, num_htlcs=1, htlc_signature=htlc_sig))
@@ -1117,37 +1124,23 @@ class Peer(PrintError):
assert self.channel_state[channel_id] == "OPEN"
their_revstore = chan.remote_state.revocation_store
cltv_expiry = int.from_bytes(htlc["cltv_expiry"], 'big')
# TODO verify sanity of their cltv expiry
amount_msat = int.from_bytes(htlc["amount_msat"], 'big')
assert amount_msat == expected_received_msat
payment_hash = htlc["payment_hash"]
htlc = UpdateAddHtlc(amount_msat, payment_hash, cltv_expiry, 0)
m = HTLCStateMachine(chan)
m.receive_htlc(htlc)
data = commitment_signed_msg["htlc_signature"]
htlc_sigs = [data[i:i+64] for i in range(0, len(data), 64)]
m.receive_new_commitment(commitment_signed_msg["signature"], htlc_sigs)
chan, last_secret, this_point, next_point = self.derive_and_incr(chan)
remote_htlc_pubkey = derive_pubkey(chan.remote_config.htlc_basepoint.pubkey, this_point)
local_htlc_pubkey = derive_pubkey(chan.local_config.htlc_basepoint.pubkey, this_point)
remote_revocation_pubkey = derive_blinded_pubkey(chan.remote_config.revocation_basepoint.pubkey, this_point)
htlcs_in_local = [
(
make_received_htlc(remote_revocation_pubkey, remote_htlc_pubkey, local_htlc_pubkey, payment_hash, cltv_expiry),
amount_msat
)
]
new_commitment = make_commitment_using_open_channel(chan, chan.local_state.ctn, True, this_point,
chan.local_state.amount_msat,
chan.remote_state.amount_msat - expected_received_msat,
htlcs_in_local)
preimage_hex = new_commitment.serialize_preimage(0)
pre_hash = bitcoin.Hash(bfh(preimage_hex))
if not ecc.verify_signature(chan.remote_config.multisig_key.pubkey, commitment_signed_msg["signature"], pre_hash):
raise Exception('failed verifying signature of our updated commitment transaction')
htlc_sigs_len = len(commitment_signed_msg["htlc_signature"])
if htlc_sigs_len != 64:
raise Exception("unexpected number of htlc signatures: " + str(htlc_sigs_len))
htlc_tx = make_htlc_tx_with_open_channel(chan, this_point, True, True, amount_msat, cltv_expiry, payment_hash, new_commitment, 0)
pre_hash = bitcoin.Hash(bfh(htlc_tx.serialize_preimage(0)))
remote_htlc_pubkey = derive_pubkey(chan.remote_config.htlc_basepoint.pubkey, this_point)
if not ecc.verify_signature(remote_htlc_pubkey, commitment_signed_msg["htlc_signature"], pre_hash):
raise Exception("failed verifying signature an HTLC tx spending from one of our commit tx'es HTLC outputs")
their_revstore.add_next_entry(last_secret)
self.send_message(gen_msg("revoke_and_ack",