use util::sha2::Sha256;
use util::{byte_utils, events};
-use std::collections::HashMap;
+use std::collections::{HashMap, hash_map};
use std::sync::{Arc,Mutex};
use std::{hash,cmp, mem};
#[derive(Debug)]
pub struct MonitorUpdateError(pub &'static str);
+/// Simple structure send back by ManyChannelMonitor in case of HTLC detected onchain from a
+/// forward channel and from which info are needed to update HTLC in a backward channel.
+pub struct HTLCUpdate {
+ pub(super) payment_hash: [u8; 32],
+ pub(super) payment_preimage: Option<[u8; 32]>,
+ pub(super) source: HTLCSource
+}
+
/// Simple trait indicating ability to track a set of ChannelMonitors and multiplex events between
/// them. Generally should be implemented by keeping a local SimpleManyChannelMonitor and passing
/// events to it, while also taking any add_update_monitor events and passing them to some remote
/// ChainWatchInterfaces such that the provided monitor receives block_connected callbacks with
/// any spends of it.
fn add_update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor) -> Result<(), ChannelMonitorUpdateErr>;
+
+ /// Used by ChannelManager to get list of HTLC resolved onchain and which needed to be updated
+ /// with success or failure backward
+ fn fetch_pending_htlc_updated(&self) -> Vec<HTLCUpdate>;
}
/// A simple implementation of a ManyChannelMonitor and ChainListener. Can be used to create a
chain_monitor: Arc<ChainWatchInterface>,
broadcaster: Arc<BroadcasterInterface>,
pending_events: Mutex<Vec<events::Event>>,
+ pending_htlc_updated: Mutex<HashMap<[u8; 32], Vec<(HTLCSource, Option<[u8; 32]>)>>>,
logger: Arc<Logger>,
}
fn block_connected(&self, header: &BlockHeader, height: u32, txn_matched: &[&Transaction], _indexes_of_txn_matched: &[u32]) {
let block_hash = header.bitcoin_hash();
let mut new_events: Vec<events::Event> = Vec::with_capacity(0);
+ let mut htlc_updated_infos = Vec::new();
{
let mut monitors = self.monitors.lock().unwrap();
for monitor in monitors.values_mut() {
- let (txn_outputs, spendable_outputs) = monitor.block_connected(txn_matched, height, &block_hash, &*self.broadcaster);
+ let (txn_outputs, spendable_outputs, mut htlc_updated) = monitor.block_connected(txn_matched, height, &block_hash, &*self.broadcaster);
if spendable_outputs.len() > 0 {
new_events.push(events::Event::SpendableOutputs {
outputs: spendable_outputs,
});
}
+
for (ref txid, ref outputs) in txn_outputs {
for (idx, output) in outputs.iter().enumerate() {
self.chain_monitor.install_watch_outpoint((txid.clone(), idx as u32), &output.script_pubkey);
}
}
+ htlc_updated_infos.append(&mut htlc_updated);
+ }
+ }
+ {
+ // ChannelManager will just need to fetch pending_htlc_updated and pass state backward
+ let mut pending_htlc_updated = self.pending_htlc_updated.lock().unwrap();
+ for htlc in htlc_updated_infos.drain(..) {
+ match pending_htlc_updated.entry(htlc.2) {
+ hash_map::Entry::Occupied(mut e) => {
+ // In case of reorg we may have htlc outputs solved in a different way so
+ // we prefer to keep claims but don't store duplicate updates for a given
+ // (payment_hash, HTLCSource) pair.
+ // TODO: Note that we currently don't really use this as ChannelManager
+ // will fail/claim backwards after the first block. We really should delay
+ // a few blocks before failing backwards (but can claim backwards
+ // immediately) as long as we have a few blocks of headroom.
+ let mut existing_claim = false;
+ e.get_mut().retain(|htlc_data| {
+ if htlc.0 == htlc_data.0 {
+ if htlc_data.1.is_some() {
+ existing_claim = true;
+ true
+ } else { false }
+ } else { true }
+ });
+ if !existing_claim {
+ e.get_mut().push((htlc.0, htlc.1));
+ }
+ }
+ hash_map::Entry::Vacant(e) => {
+ e.insert(vec![(htlc.0, htlc.1)]);
+ }
+ }
}
}
let mut pending_events = self.pending_events.lock().unwrap();
chain_monitor,
broadcaster,
pending_events: Mutex::new(Vec::new()),
+ pending_htlc_updated: Mutex::new(HashMap::new()),
logger,
});
let weak_res = Arc::downgrade(&res);
Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
}
}
+
+ fn fetch_pending_htlc_updated(&self) -> Vec<HTLCUpdate> {
+ let mut updated = self.pending_htlc_updated.lock().unwrap();
+ let mut pending_htlcs_updated = Vec::with_capacity(updated.len());
+ for (k, v) in updated.drain() {
+ for htlc_data in v {
+ pending_htlcs_updated.push(HTLCUpdate {
+ payment_hash: k,
+ payment_preimage: htlc_data.1,
+ source: htlc_data.0,
+ });
+ }
+ }
+ pending_htlcs_updated
+ }
}
impl<Key : Send + cmp::Eq + hash::Hash> events::EventsProvider for SimpleManyChannelMonitor<Key> {
/// data in remote_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
/// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
/// HTLC-Success/HTLC-Timeout transactions.
- fn check_spend_remote_transaction(&mut self, tx: &Transaction, height: u32) -> (Vec<Transaction>, (Sha256dHash, Vec<TxOut>), Vec<SpendableOutputDescriptor>) {
+ /// Return updates for HTLC pending in the channel and failed automatically by the broadcast of
+ /// revoked remote commitment tx
+ fn check_spend_remote_transaction(&mut self, tx: &Transaction, height: u32) -> (Vec<Transaction>, (Sha256dHash, Vec<TxOut>), Vec<SpendableOutputDescriptor>, Vec<(HTLCSource, Option<[u8;32]>, [u8;32])>) {
// Most secp and related errors trying to create keys means we have no hope of constructing
// a spend transaction...so we return no transactions to broadcast
let mut txn_to_broadcast = Vec::new();
let mut watch_outputs = Vec::new();
let mut spendable_outputs = Vec::new();
+ let mut htlc_updated = Vec::new();
let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
let per_commitment_option = self.remote_claimable_outpoints.get(&commitment_txid);
( $thing : expr ) => {
match $thing {
Ok(a) => a,
- Err(_) => return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs)
+ Err(_) => return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs, htlc_updated)
}
};
}
};
let delayed_key = ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key), &self.their_delayed_payment_base_key.unwrap()));
let a_htlc_key = match self.their_htlc_base_key {
- None => return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs),
+ None => return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs, htlc_updated),
Some(their_htlc_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key), &their_htlc_base_key)),
};
if htlc.transaction_output_index as usize >= tx.output.len() ||
tx.output[htlc.transaction_output_index as usize].value != htlc.amount_msat / 1000 ||
tx.output[htlc.transaction_output_index as usize].script_pubkey != expected_script.to_v0_p2wsh() {
- return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs); // Corrupted per_commitment_data, fuck this user
+ return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs, htlc_updated); // Corrupted per_commitment_data, fuck this user
}
let input = TxIn {
previous_output: BitcoinOutPoint {
watch_outputs.append(&mut tx.output.clone());
self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
}
- if inputs.is_empty() { return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs); } // Nothing to be done...probably a false positive/local tx
+ if inputs.is_empty() { return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs, htlc_updated); } // Nothing to be done...probably a false positive/local tx
let outputs = vec!(TxOut {
script_pubkey: self.destination_script.clone(),
},
};
let a_htlc_key = match self.their_htlc_base_key {
- None => return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs),
+ None => return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs, htlc_updated),
Some(their_htlc_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &their_htlc_base_key)),
};
if htlc.transaction_output_index as usize >= tx.output.len() ||
tx.output[htlc.transaction_output_index as usize].value != htlc.amount_msat / 1000 ||
tx.output[htlc.transaction_output_index as usize].script_pubkey != expected_script.to_v0_p2wsh() {
- return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs); // Corrupted per_commitment_data, fuck this user
+ return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs, htlc_updated); // Corrupted per_commitment_data, fuck this user
}
if let Some(payment_preimage) = self.payment_preimages.get(&htlc.payment_hash) {
let input = TxIn {
}
}
- if inputs.is_empty() { return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs); } // Nothing to be done...probably a false positive/local tx
+ if inputs.is_empty() { return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs, htlc_updated); } // Nothing to be done...probably a false positive/local tx
let outputs = vec!(TxOut {
script_pubkey: self.destination_script.clone(),
}
}
- (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs)
+ (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs, htlc_updated)
}
/// Attempst to claim a remote HTLC-Success/HTLC-Timeout s outputs using the revocation key
}
}
- fn block_connected(&mut self, txn_matched: &[&Transaction], height: u32, block_hash: &Sha256dHash, broadcaster: &BroadcasterInterface)-> (Vec<(Sha256dHash, Vec<TxOut>)>, Vec<SpendableOutputDescriptor>) {
+ fn block_connected(&mut self, txn_matched: &[&Transaction], height: u32, block_hash: &Sha256dHash, broadcaster: &BroadcasterInterface)-> (Vec<(Sha256dHash, Vec<TxOut>)>, Vec<SpendableOutputDescriptor>, Vec<(HTLCSource, Option<[u8 ; 32]>, [u8; 32])>) {
let mut watch_outputs = Vec::new();
let mut spendable_outputs = Vec::new();
+ let mut htlc_updated = Vec::new();
for tx in txn_matched {
if tx.input.len() == 1 {
// Assuming our keys were not leaked (in which case we're screwed no matter what),
}
};
if funding_txo.is_none() || (prevout.txid == funding_txo.as_ref().unwrap().0.txid && prevout.vout == funding_txo.as_ref().unwrap().0.index as u32) {
- let (remote_txn, new_outputs, mut spendable_output) = self.check_spend_remote_transaction(tx, height);
+ let (remote_txn, new_outputs, mut spendable_output, mut updated) = self.check_spend_remote_transaction(tx, height);
txn = remote_txn;
spendable_outputs.append(&mut spendable_output);
if !new_outputs.1.is_empty() {
spendable_outputs.push(spendable_output);
}
}
+ if updated.len() > 0 {
+ htlc_updated.append(&mut updated);
+ }
} 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);
for tx in txn.iter() {
broadcaster.broadcast_transaction(tx);
}
+ let mut updated = self.is_resolving_htlc_output(tx);
+ if updated.len() > 0 {
+ htlc_updated.append(&mut updated);
+ }
}
}
if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
}
}
self.last_block_hash = block_hash.clone();
- (watch_outputs, spendable_outputs)
+ (watch_outputs, spendable_outputs, htlc_updated)
}
pub(super) fn would_broadcast_at_height(&self, height: u32) -> bool {
}
false
}
+
+ /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a local
+ /// or remote commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
+ fn is_resolving_htlc_output(&mut self, tx: &Transaction) -> Vec<(HTLCSource, Option<[u8;32]>, [u8;32])> {
+ let mut htlc_updated = Vec::new();
+
+ 'outer_loop: for input in &tx.input {
+ let mut payment_data = None;
+
+ macro_rules! scan_commitment {
+ ($htlc_outputs: expr, $htlc_sources: expr) => {
+ for &(ref payment_hash, ref source, ref vout) in $htlc_sources.iter() {
+ if &Some(input.previous_output.vout) == vout {
+ payment_data = Some((source.clone(), *payment_hash));
+ }
+ }
+ if payment_data.is_none() {
+ for htlc_output in $htlc_outputs {
+ if input.previous_output.vout == htlc_output.transaction_output_index {
+ log_info!(self, "Inbound HTLC timeout at {} from {} resolved by {}", input.previous_output.vout, input.previous_output.txid, tx.txid());
+ continue 'outer_loop;
+ }
+ }
+ }
+ }
+ }
+
+ if let Some(ref current_local_signed_commitment_tx) = self.current_local_signed_commitment_tx {
+ if input.previous_output.txid == current_local_signed_commitment_tx.txid {
+ scan_commitment!(current_local_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a), current_local_signed_commitment_tx.htlc_sources);
+ }
+ }
+ if let Some(ref prev_local_signed_commitment_tx) = self.prev_local_signed_commitment_tx {
+ if input.previous_output.txid == prev_local_signed_commitment_tx.txid {
+ scan_commitment!(prev_local_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a), prev_local_signed_commitment_tx.htlc_sources);
+ }
+ }
+ if let Some(&(ref htlc_outputs, ref htlc_sources)) = self.remote_claimable_outpoints.get(&input.previous_output.txid) {
+ scan_commitment!(htlc_outputs, htlc_sources);
+ }
+
+ // If tx isn't solving htlc output from local/remote commitment tx and htlc isn't outbound we don't need
+ // to broadcast solving backward
+ if let Some((source, payment_hash)) = payment_data {
+ let mut payment_preimage = [0; 32];
+ if input.witness.len() == 5 && input.witness[4].len() == 138 {
+ payment_preimage.copy_from_slice(&tx.input[0].witness[3]);
+ htlc_updated.push((source, Some(payment_preimage), payment_hash));
+ } else if input.witness.len() == 3 && input.witness[2].len() == 133 {
+ payment_preimage.copy_from_slice(&tx.input[0].witness[1]);
+ htlc_updated.push((source, Some(payment_preimage), payment_hash));
+ } else {
+ htlc_updated.push((source, None, payment_hash));
+ }
+ }
+ }
+ htlc_updated
+ }
}
const MAX_ALLOC_SIZE: usize = 64*1024;
projects / rust-lightning / blobdiff