From 1255885a803d0f56047a4f90f5a56faf70b306ae Mon Sep 17 00:00:00 2001 From: Antoine Riard Date: Fri, 16 Nov 2018 20:52:33 -0500 Subject: [PATCH] Add check_spend_closing_transaction ChannelMonitor Aims to send back closing output descriptor to user wallet --- src/ln/channel.rs | 4 +-- src/ln/channelmonitor.rs | 67 +++++++++++++++++++++++++++++++--------- 2 files changed, 54 insertions(+), 17 deletions(-) diff --git a/src/ln/channel.rs b/src/ln/channel.rs index 6172c5fff..1e30f5c99 100644 --- a/src/ln/channel.rs +++ b/src/ln/channel.rs @@ -436,7 +436,7 @@ impl Channel { let secp_ctx = Secp256k1::new(); let channel_monitor = ChannelMonitor::new(&chan_keys.revocation_base_key, &chan_keys.delayed_payment_base_key, - &chan_keys.htlc_base_key, &chan_keys.payment_base_key, BREAKDOWN_TIMEOUT, + &chan_keys.htlc_base_key, &chan_keys.payment_base_key, &keys_provider.get_shutdown_pubkey(), BREAKDOWN_TIMEOUT, keys_provider.get_destination_script(), logger.clone()); Ok(Channel { @@ -624,7 +624,7 @@ impl Channel { let secp_ctx = Secp256k1::new(); let mut channel_monitor = ChannelMonitor::new(&chan_keys.revocation_base_key, &chan_keys.delayed_payment_base_key, - &chan_keys.htlc_base_key, &chan_keys.payment_base_key, BREAKDOWN_TIMEOUT, + &chan_keys.htlc_base_key, &chan_keys.payment_base_key, &keys_provider.get_shutdown_pubkey(), BREAKDOWN_TIMEOUT, keys_provider.get_destination_script(), logger.clone()); channel_monitor.set_their_base_keys(&msg.htlc_basepoint, &msg.delayed_payment_basepoint); channel_monitor.provide_their_next_revocation_point(Some((INITIAL_COMMITMENT_NUMBER, msg.first_per_commitment_point))); diff --git a/src/ln/channelmonitor.rs b/src/ln/channelmonitor.rs index dc390f5dd..8b209c1e7 100644 --- a/src/ln/channelmonitor.rs +++ b/src/ln/channelmonitor.rs @@ -14,9 +14,10 @@ use bitcoin::blockdata::block::BlockHeader; use bitcoin::blockdata::transaction::{TxIn,TxOut,SigHashType,Transaction}; use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint; -use bitcoin::blockdata::script::Script; +use bitcoin::blockdata::script::{Script, Builder}; +use bitcoin::blockdata::opcodes; use bitcoin::consensus::encode::{self, Decodable, Encodable}; -use bitcoin::util::hash::{BitcoinHash,Sha256dHash}; +use bitcoin::util::hash::{Hash160, BitcoinHash,Sha256dHash}; use bitcoin::util::bip143; use crypto::digest::Digest; @@ -220,6 +221,7 @@ enum KeyStorage { htlc_base_key: SecretKey, delayed_payment_base_key: SecretKey, payment_base_key: SecretKey, + shutdown_pubkey: PublicKey, prev_latest_per_commitment_point: Option, latest_per_commitment_point: Option, }, @@ -339,7 +341,7 @@ impl PartialEq for ChannelMonitor { } impl ChannelMonitor { - pub(super) fn new(revocation_base_key: &SecretKey, delayed_payment_base_key: &SecretKey, htlc_base_key: &SecretKey, payment_base_key: &SecretKey, our_to_self_delay: u16, destination_script: Script, logger: Arc) -> ChannelMonitor { + pub(super) fn new(revocation_base_key: &SecretKey, delayed_payment_base_key: &SecretKey, htlc_base_key: &SecretKey, payment_base_key: &SecretKey, shutdown_pubkey: &PublicKey, our_to_self_delay: u16, destination_script: Script, logger: Arc) -> ChannelMonitor { ChannelMonitor { funding_txo: None, commitment_transaction_number_obscure_factor: 0, @@ -349,6 +351,7 @@ impl ChannelMonitor { htlc_base_key: htlc_base_key.clone(), delayed_payment_base_key: delayed_payment_base_key.clone(), payment_base_key: payment_base_key.clone(), + shutdown_pubkey: shutdown_pubkey.clone(), prev_latest_per_commitment_point: None, latest_per_commitment_point: None, }, @@ -512,12 +515,13 @@ impl ChannelMonitor { feerate_per_kw, htlc_outputs, }); - self.key_storage = if let KeyStorage::PrivMode { ref revocation_base_key, ref htlc_base_key, ref delayed_payment_base_key, ref payment_base_key, ref latest_per_commitment_point, .. } = self.key_storage { + self.key_storage = if let KeyStorage::PrivMode { ref revocation_base_key, ref htlc_base_key, ref delayed_payment_base_key, ref payment_base_key, ref shutdown_pubkey, ref latest_per_commitment_point, .. } = self.key_storage { KeyStorage::PrivMode { revocation_base_key: *revocation_base_key, htlc_base_key: *htlc_base_key, delayed_payment_base_key: *delayed_payment_base_key, payment_base_key: *payment_base_key, + shutdown_pubkey: *shutdown_pubkey, prev_latest_per_commitment_point: *latest_per_commitment_point, latest_per_commitment_point: Some(local_keys.per_commitment_point), } @@ -643,12 +647,13 @@ impl ChannelMonitor { U48(self.commitment_transaction_number_obscure_factor).write(writer)?; match self.key_storage { - KeyStorage::PrivMode { ref revocation_base_key, ref htlc_base_key, ref delayed_payment_base_key, ref payment_base_key, ref prev_latest_per_commitment_point, ref latest_per_commitment_point } => { + KeyStorage::PrivMode { ref revocation_base_key, ref htlc_base_key, ref delayed_payment_base_key, ref payment_base_key, ref shutdown_pubkey, ref prev_latest_per_commitment_point, ref latest_per_commitment_point } => { writer.write_all(&[0; 1])?; writer.write_all(&revocation_base_key[..])?; writer.write_all(&htlc_base_key[..])?; writer.write_all(&delayed_payment_base_key[..])?; writer.write_all(&payment_base_key[..])?; + writer.write_all(&shutdown_pubkey.serialize())?; if let Some(ref prev_latest_per_commitment_point) = *prev_latest_per_commitment_point { writer.write_all(&[1; 1])?; writer.write_all(&prev_latest_per_commitment_point.serialize())?; @@ -1374,6 +1379,31 @@ impl ChannelMonitor { (Vec::new(), Vec::new()) } + /// Generate a spendable output event when closing_transaction get registered onchain. + fn check_spend_closing_transaction(&self, tx: &Transaction) -> Option { + if tx.input[0].sequence == 0xFFFFFFFF && tx.input[0].witness.last().unwrap().len() == 71 { + match self.key_storage { + KeyStorage::PrivMode { ref shutdown_pubkey, .. } => { + let our_channel_close_key_hash = Hash160::from_data(&shutdown_pubkey.serialize()); + let shutdown_script = Builder::new().push_opcode(opcodes::All::OP_PUSHBYTES_0).push_slice(&our_channel_close_key_hash[..]).into_script(); + for (idx, output) in tx.output.iter().enumerate() { + if shutdown_script == output.script_pubkey { + return Some(SpendableOutputDescriptor::StaticOutput { + outpoint: BitcoinOutPoint { txid: tx.txid(), vout: idx as u32 }, + output: output.clone(), + }); + } + } + } + KeyStorage::SigsMode { .. } => { + //TODO: we need to ensure an offline client will generate the event when it + // cames back online after only the watchtower saw the transaction + } + } + } + None + } + /// Used by ChannelManager deserialization to broadcast the latest local state if it's copy of /// the Channel was out-of-date. pub(super) fn get_latest_local_commitment_txn(&self) -> Vec { @@ -1414,6 +1444,11 @@ impl ChannelMonitor { spendable_outputs.append(&mut outputs); txn = remote_txn; } + if !self.funding_txo.is_none() && txn.is_empty() { + if let Some(spendable_output) = self.check_spend_closing_transaction(tx) { + spendable_outputs.push(spendable_output); + } + } } else { if let Some(&(commitment_number, _)) = self.remote_commitment_txn_on_chain.get(&prevout.txid) { let (tx, spendable_output) = self.check_spend_remote_htlc(tx, commitment_number); @@ -1523,6 +1558,7 @@ impl ReadableArgs> for (Sha256dHash, ChannelM let htlc_base_key = Readable::read(reader)?; let delayed_payment_base_key = Readable::read(reader)?; let payment_base_key = Readable::read(reader)?; + let shutdown_pubkey = Readable::read(reader)?; let prev_latest_per_commitment_point = match >::read(reader)? { 0 => None, 1 => Some(Readable::read(reader)?), @@ -1538,6 +1574,7 @@ impl ReadableArgs> for (Sha256dHash, ChannelM htlc_base_key, delayed_payment_base_key, payment_base_key, + shutdown_pubkey, prev_latest_per_commitment_point, latest_per_commitment_point, } @@ -1767,7 +1804,7 @@ mod tests { { // insert_secret correct sequence - monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), 0, Script::new(), logger.clone()); + monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone()); secrets.clear(); secrets.push([0; 32]); @@ -1813,7 +1850,7 @@ mod tests { { // insert_secret #1 incorrect - monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), 0, Script::new(), logger.clone()); + monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone()); secrets.clear(); secrets.push([0; 32]); @@ -1829,7 +1866,7 @@ mod tests { { // insert_secret #2 incorrect (#1 derived from incorrect) - monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), 0, Script::new(), logger.clone()); + monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone()); secrets.clear(); secrets.push([0; 32]); @@ -1855,7 +1892,7 @@ mod tests { { // insert_secret #3 incorrect - monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), 0, Script::new(), logger.clone()); + monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone()); secrets.clear(); secrets.push([0; 32]); @@ -1881,7 +1918,7 @@ mod tests { { // insert_secret #4 incorrect (1,2,3 derived from incorrect) - monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), 0, Script::new(), logger.clone()); + monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone()); secrets.clear(); secrets.push([0; 32]); @@ -1927,7 +1964,7 @@ mod tests { { // insert_secret #5 incorrect - monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), 0, Script::new(), logger.clone()); + monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone()); secrets.clear(); secrets.push([0; 32]); @@ -1963,7 +2000,7 @@ mod tests { { // insert_secret #6 incorrect (5 derived from incorrect) - monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), 0, Script::new(), logger.clone()); + monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone()); secrets.clear(); secrets.push([0; 32]); @@ -2009,7 +2046,7 @@ mod tests { { // insert_secret #7 incorrect - monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), 0, Script::new(), logger.clone()); + monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone()); secrets.clear(); secrets.push([0; 32]); @@ -2055,7 +2092,7 @@ mod tests { { // insert_secret #8 incorrect - monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), 0, Script::new(), logger.clone()); + monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone()); secrets.clear(); secrets.push([0; 32]); @@ -2174,7 +2211,7 @@ mod tests { // Prune with one old state and a local commitment tx holding a few overlaps with the // old state. - let mut monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), 0, Script::new(), logger.clone()); + let mut monitor = ChannelMonitor::new(&SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[43; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &SecretKey::from_slice(&secp_ctx, &[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[45; 32]).unwrap()), 0, Script::new(), logger.clone()); monitor.set_their_to_self_delay(10); monitor.provide_latest_local_commitment_tx_info(dummy_tx.clone(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..10])); -- 2.39.5