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#![deny(broken_intra_doc_links)]
#![deny(missing_docs)]
#![deny(unsafe_code)]
#[macro_use] extern crate lightning;
use lightning::chain;
use lightning::chain::chaininterface::{BroadcasterInterface, FeeEstimator};
use lightning::chain::chainmonitor::ChainMonitor;
use lightning::chain::channelmonitor;
use lightning::chain::keysinterface::{Sign, KeysInterface};
use lightning::ln::channelmanager::ChannelManager;
use lightning::ln::msgs::{ChannelMessageHandler, RoutingMessageHandler};
use lightning::ln::peer_handler::{PeerManager, SocketDescriptor};
use lightning::util::events::{EventHandler, EventsProvider};
use lightning::util::logger::Logger;
use std::sync::Arc;
use std::sync::atomic::{AtomicBool, Ordering};
use std::thread;
use std::thread::JoinHandle;
use std::time::{Duration, Instant};
use std::ops::Deref;
#[must_use = "BackgroundProcessor will immediately stop on drop. It should be stored until shutdown."]
pub struct BackgroundProcessor {
stop_thread: Arc<AtomicBool>,
thread_handle: Option<JoinHandle<Result<(), std::io::Error>>>,
}
#[cfg(not(test))]
const FRESHNESS_TIMER: u64 = 60;
#[cfg(test)]
const FRESHNESS_TIMER: u64 = 1;
const PING_TIMER: u64 = 5;
pub trait ChannelManagerPersister<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
where
M::Target: 'static + chain::Watch<Signer>,
T::Target: 'static + BroadcasterInterface,
K::Target: 'static + KeysInterface<Signer = Signer>,
F::Target: 'static + FeeEstimator,
L::Target: 'static + Logger,
{
fn persist_manager(&self, channel_manager: &ChannelManager<Signer, M, T, K, F, L>) -> Result<(), std::io::Error>;
}
impl<Fun, Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
ChannelManagerPersister<Signer, M, T, K, F, L> for Fun where
M::Target: 'static + chain::Watch<Signer>,
T::Target: 'static + BroadcasterInterface,
K::Target: 'static + KeysInterface<Signer = Signer>,
F::Target: 'static + FeeEstimator,
L::Target: 'static + Logger,
Fun: Fn(&ChannelManager<Signer, M, T, K, F, L>) -> Result<(), std::io::Error>,
{
fn persist_manager(&self, channel_manager: &ChannelManager<Signer, M, T, K, F, L>) -> Result<(), std::io::Error> {
self(channel_manager)
}
}
impl BackgroundProcessor {
pub fn start<
Signer: 'static + Sign,
CF: 'static + Deref + Send + Sync,
CW: 'static + Deref + Send + Sync,
T: 'static + Deref + Send + Sync,
K: 'static + Deref + Send + Sync,
F: 'static + Deref + Send + Sync,
L: 'static + Deref + Send + Sync,
P: 'static + Deref + Send + Sync,
Descriptor: 'static + SocketDescriptor + Send + Sync,
CMH: 'static + Deref + Send + Sync,
RMH: 'static + Deref + Send + Sync,
EH: 'static + EventHandler + Send + Sync,
CMP: 'static + Send + ChannelManagerPersister<Signer, CW, T, K, F, L>,
M: 'static + Deref<Target = ChainMonitor<Signer, CF, T, F, L, P>> + Send + Sync,
CM: 'static + Deref<Target = ChannelManager<Signer, CW, T, K, F, L>> + Send + Sync,
PM: 'static + Deref<Target = PeerManager<Descriptor, CMH, RMH, L>> + Send + Sync,
>
(persister: CMP, event_handler: EH, chain_monitor: M, channel_manager: CM, peer_manager: PM, logger: L) -> Self
where
CF::Target: 'static + chain::Filter,
CW::Target: 'static + chain::Watch<Signer>,
T::Target: 'static + BroadcasterInterface,
K::Target: 'static + KeysInterface<Signer = Signer>,
F::Target: 'static + FeeEstimator,
L::Target: 'static + Logger,
P::Target: 'static + channelmonitor::Persist<Signer>,
CMH::Target: 'static + ChannelMessageHandler,
RMH::Target: 'static + RoutingMessageHandler,
{
let stop_thread = Arc::new(AtomicBool::new(false));
let stop_thread_clone = stop_thread.clone();
let handle = thread::spawn(move || -> Result<(), std::io::Error> {
log_trace!(logger, "Calling ChannelManager's timer_tick_occurred on startup");
channel_manager.timer_tick_occurred();
let mut last_freshness_call = Instant::now();
let mut last_ping_call = Instant::now();
loop {
peer_manager.process_events();
channel_manager.process_pending_events(&event_handler);
chain_monitor.process_pending_events(&event_handler);
let updates_available =
channel_manager.await_persistable_update_timeout(Duration::from_millis(100));
if updates_available {
persister.persist_manager(&*channel_manager)?;
}
if stop_thread.load(Ordering::Acquire) == true {
log_trace!(logger, "Terminating background processor.");
return Ok(());
}
if last_freshness_call.elapsed().as_secs() > FRESHNESS_TIMER {
log_trace!(logger, "Calling ChannelManager's timer_tick_occurred");
channel_manager.timer_tick_occurred();
last_freshness_call = Instant::now();
}
if last_ping_call.elapsed().as_secs() > PING_TIMER * 2 {
log_trace!(logger, "Awoke after more than double our ping timer, disconnecting peers.");
peer_manager.timer_tick_occurred();
peer_manager.timer_tick_occurred();
last_ping_call = Instant::now();
} else if last_ping_call.elapsed().as_secs() > PING_TIMER {
log_trace!(logger, "Calling PeerManager's timer_tick_occurred");
peer_manager.timer_tick_occurred();
last_ping_call = Instant::now();
}
}
});
Self { stop_thread: stop_thread_clone, thread_handle: Some(handle) }
}
pub fn join(mut self) -> Result<(), std::io::Error> {
assert!(self.thread_handle.is_some());
self.join_thread()
}
pub fn stop(mut self) -> Result<(), std::io::Error> {
assert!(self.thread_handle.is_some());
self.stop_and_join_thread()
}
fn stop_and_join_thread(&mut self) -> Result<(), std::io::Error> {
self.stop_thread.store(true, Ordering::Release);
self.join_thread()
}
fn join_thread(&mut self) -> Result<(), std::io::Error> {
match self.thread_handle.take() {
Some(handle) => handle.join().unwrap(),
None => Ok(()),
}
}
}
impl Drop for BackgroundProcessor {
fn drop(&mut self) {
self.stop_and_join_thread().unwrap();
}
}
#[cfg(test)]
mod tests {
use bitcoin::blockdata::block::BlockHeader;
use bitcoin::blockdata::constants::genesis_block;
use bitcoin::blockdata::transaction::{Transaction, TxOut};
use bitcoin::network::constants::Network;
use lightning::chain::{BestBlock, Confirm, chainmonitor};
use lightning::chain::channelmonitor::ANTI_REORG_DELAY;
use lightning::chain::keysinterface::{InMemorySigner, KeysInterface, KeysManager};
use lightning::chain::transaction::OutPoint;
use lightning::get_event_msg;
use lightning::ln::channelmanager::{BREAKDOWN_TIMEOUT, ChainParameters, ChannelManager, SimpleArcChannelManager};
use lightning::ln::features::InitFeatures;
use lightning::ln::msgs::{ChannelMessageHandler, Init};
use lightning::ln::peer_handler::{PeerManager, MessageHandler, SocketDescriptor};
use lightning::util::config::UserConfig;
use lightning::util::events::{Event, MessageSendEventsProvider, MessageSendEvent};
use lightning::util::ser::Writeable;
use lightning::util::test_utils;
use lightning_persister::FilesystemPersister;
use std::fs;
use std::path::PathBuf;
use std::sync::{Arc, Mutex};
use std::time::Duration;
use super::{BackgroundProcessor, FRESHNESS_TIMER};
const EVENT_DEADLINE: u64 = 5 * FRESHNESS_TIMER;
#[derive(Clone, Eq, Hash, PartialEq)]
struct TestDescriptor{}
impl SocketDescriptor for TestDescriptor {
fn send_data(&mut self, _data: &[u8], _resume_read: bool) -> usize {
0
}
fn disconnect_socket(&mut self) {}
}
type ChainMonitor = chainmonitor::ChainMonitor<InMemorySigner, Arc<test_utils::TestChainSource>, Arc<test_utils::TestBroadcaster>, Arc<test_utils::TestFeeEstimator>, Arc<test_utils::TestLogger>, Arc<FilesystemPersister>>;
struct Node {
node: Arc<SimpleArcChannelManager<ChainMonitor, test_utils::TestBroadcaster, test_utils::TestFeeEstimator, test_utils::TestLogger>>,
peer_manager: Arc<PeerManager<TestDescriptor, Arc<test_utils::TestChannelMessageHandler>, Arc<test_utils::TestRoutingMessageHandler>, Arc<test_utils::TestLogger>>>,
chain_monitor: Arc<ChainMonitor>,
persister: Arc<FilesystemPersister>,
tx_broadcaster: Arc<test_utils::TestBroadcaster>,
logger: Arc<test_utils::TestLogger>,
best_block: BestBlock,
}
impl Drop for Node {
fn drop(&mut self) {
let data_dir = self.persister.get_data_dir();
match fs::remove_dir_all(data_dir.clone()) {
Err(e) => println!("Failed to remove test persister directory {}: {}", data_dir, e),
_ => {}
}
}
}
fn get_full_filepath(filepath: String, filename: String) -> String {
let mut path = PathBuf::from(filepath);
path.push(filename);
path.to_str().unwrap().to_string()
}
fn create_nodes(num_nodes: usize, persist_dir: String) -> Vec<Node> {
let mut nodes = Vec::new();
for i in 0..num_nodes {
let tx_broadcaster = Arc::new(test_utils::TestBroadcaster{txn_broadcasted: Mutex::new(Vec::new()), blocks: Arc::new(Mutex::new(Vec::new()))});
let fee_estimator = Arc::new(test_utils::TestFeeEstimator { sat_per_kw: Mutex::new(253) });
let chain_source = Arc::new(test_utils::TestChainSource::new(Network::Testnet));
let logger = Arc::new(test_utils::TestLogger::with_id(format!("node {}", i)));
let persister = Arc::new(FilesystemPersister::new(format!("{}_persister_{}", persist_dir, i)));
let seed = [i as u8; 32];
let network = Network::Testnet;
let now = Duration::from_secs(genesis_block(network).header.time as u64);
let keys_manager = Arc::new(KeysManager::new(&seed, now.as_secs(), now.subsec_nanos()));
let chain_monitor = Arc::new(chainmonitor::ChainMonitor::new(Some(chain_source.clone()), tx_broadcaster.clone(), logger.clone(), fee_estimator.clone(), persister.clone()));
let best_block = BestBlock::from_genesis(network);
let params = ChainParameters { network, best_block };
let manager = Arc::new(ChannelManager::new(fee_estimator.clone(), chain_monitor.clone(), tx_broadcaster.clone(), logger.clone(), keys_manager.clone(), UserConfig::default(), params));
let msg_handler = MessageHandler { chan_handler: Arc::new(test_utils::TestChannelMessageHandler::new()), route_handler: Arc::new(test_utils::TestRoutingMessageHandler::new() )};
let peer_manager = Arc::new(PeerManager::new(msg_handler, keys_manager.get_node_secret(), &seed, logger.clone()));
let node = Node { node: manager, peer_manager, chain_monitor, persister, tx_broadcaster, logger, best_block };
nodes.push(node);
}
for i in 0..num_nodes {
for j in (i+1)..num_nodes {
nodes[i].node.peer_connected(&nodes[j].node.get_our_node_id(), &Init { features: InitFeatures::known() });
nodes[j].node.peer_connected(&nodes[i].node.get_our_node_id(), &Init { features: InitFeatures::known() });
}
}
nodes
}
macro_rules! open_channel {
($node_a: expr, $node_b: expr, $channel_value: expr) => {{
begin_open_channel!($node_a, $node_b, $channel_value);
let events = $node_a.node.get_and_clear_pending_events();
assert_eq!(events.len(), 1);
let (temporary_channel_id, tx) = handle_funding_generation_ready!(events[0], $channel_value);
end_open_channel!($node_a, $node_b, temporary_channel_id, tx);
tx
}}
}
macro_rules! begin_open_channel {
($node_a: expr, $node_b: expr, $channel_value: expr) => {{
$node_a.node.create_channel($node_b.node.get_our_node_id(), $channel_value, 100, 42, None).unwrap();
$node_b.node.handle_open_channel(&$node_a.node.get_our_node_id(), InitFeatures::known(), &get_event_msg!($node_a, MessageSendEvent::SendOpenChannel, $node_b.node.get_our_node_id()));
$node_a.node.handle_accept_channel(&$node_b.node.get_our_node_id(), InitFeatures::known(), &get_event_msg!($node_b, MessageSendEvent::SendAcceptChannel, $node_a.node.get_our_node_id()));
}}
}
macro_rules! handle_funding_generation_ready {
($event: expr, $channel_value: expr) => {{
match $event {
Event::FundingGenerationReady { ref temporary_channel_id, ref channel_value_satoshis, ref output_script, user_channel_id } => {
assert_eq!(*channel_value_satoshis, $channel_value);
assert_eq!(user_channel_id, 42);
let tx = Transaction { version: 1 as i32, lock_time: 0, input: Vec::new(), output: vec![TxOut {
value: *channel_value_satoshis, script_pubkey: output_script.clone(),
}]};
(*temporary_channel_id, tx)
},
_ => panic!("Unexpected event"),
}
}}
}
macro_rules! end_open_channel {
($node_a: expr, $node_b: expr, $temporary_channel_id: expr, $tx: expr) => {{
$node_a.node.funding_transaction_generated(&$temporary_channel_id, $tx.clone()).unwrap();
$node_b.node.handle_funding_created(&$node_a.node.get_our_node_id(), &get_event_msg!($node_a, MessageSendEvent::SendFundingCreated, $node_b.node.get_our_node_id()));
$node_a.node.handle_funding_signed(&$node_b.node.get_our_node_id(), &get_event_msg!($node_b, MessageSendEvent::SendFundingSigned, $node_a.node.get_our_node_id()));
}}
}
fn confirm_transaction_depth(node: &mut Node, tx: &Transaction, depth: u32) {
for i in 1..=depth {
let prev_blockhash = node.best_block.block_hash();
let height = node.best_block.height() + 1;
let header = BlockHeader { version: 0x20000000, prev_blockhash, merkle_root: Default::default(), time: height, bits: 42, nonce: 42 };
let txdata = vec![(0, tx)];
node.best_block = BestBlock::new(header.block_hash(), height);
match i {
1 => {
node.node.transactions_confirmed(&header, &txdata, height);
node.chain_monitor.transactions_confirmed(&header, &txdata, height);
},
x if x == depth => {
node.node.best_block_updated(&header, height);
node.chain_monitor.best_block_updated(&header, height);
},
_ => {},
}
}
}
fn confirm_transaction(node: &mut Node, tx: &Transaction) {
confirm_transaction_depth(node, tx, ANTI_REORG_DELAY);
}
#[test]
fn test_background_processor() {
let nodes = create_nodes(2, "test_background_processor".to_string());
let tx = open_channel!(nodes[0], nodes[1], 100000);
let data_dir = nodes[0].persister.get_data_dir();
let persister = move |node: &ChannelManager<InMemorySigner, Arc<ChainMonitor>, Arc<test_utils::TestBroadcaster>, Arc<KeysManager>, Arc<test_utils::TestFeeEstimator>, Arc<test_utils::TestLogger>>| FilesystemPersister::persist_manager(data_dir.clone(), node);
let event_handler = |_| {};
let bg_processor = BackgroundProcessor::start(persister, event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].peer_manager.clone(), nodes[0].logger.clone());
macro_rules! check_persisted_data {
($node: expr, $filepath: expr, $expected_bytes: expr) => {
match $node.write(&mut $expected_bytes) {
Ok(()) => {
loop {
match std::fs::read($filepath) {
Ok(bytes) => {
if bytes == $expected_bytes {
break
} else {
continue
}
},
Err(_) => continue
}
}
},
Err(e) => panic!("Unexpected error: {}", e)
}
}
}
let filepath = get_full_filepath("test_background_processor_persister_0".to_string(), "manager".to_string());
let mut expected_bytes = Vec::new();
check_persisted_data!(nodes[0].node, filepath.clone(), expected_bytes);
loop {
if !nodes[0].node.get_persistence_condvar_value() { break }
}
nodes[0].node.force_close_channel(&OutPoint { txid: tx.txid(), index: 0 }.to_channel_id()).unwrap();
let mut expected_bytes = Vec::new();
check_persisted_data!(nodes[0].node, filepath.clone(), expected_bytes);
loop {
if !nodes[0].node.get_persistence_condvar_value() { break }
}
assert!(bg_processor.stop().is_ok());
}
#[test]
fn test_timer_tick_called() {
let nodes = create_nodes(1, "test_timer_tick_called".to_string());
let data_dir = nodes[0].persister.get_data_dir();
let persister = move |node: &ChannelManager<InMemorySigner, Arc<ChainMonitor>, Arc<test_utils::TestBroadcaster>, Arc<KeysManager>, Arc<test_utils::TestFeeEstimator>, Arc<test_utils::TestLogger>>| FilesystemPersister::persist_manager(data_dir.clone(), node);
let event_handler = |_| {};
let bg_processor = BackgroundProcessor::start(persister, event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].peer_manager.clone(), nodes[0].logger.clone());
loop {
let log_entries = nodes[0].logger.lines.lock().unwrap();
let desired_log = "Calling ChannelManager's timer_tick_occurred".to_string();
let second_desired_log = "Calling PeerManager's timer_tick_occurred".to_string();
if log_entries.get(&("lightning_background_processor".to_string(), desired_log)).is_some() &&
log_entries.get(&("lightning_background_processor".to_string(), second_desired_log)).is_some() {
break
}
}
assert!(bg_processor.stop().is_ok());
}
#[test]
fn test_persist_error() {
let nodes = create_nodes(2, "test_persist_error".to_string());
open_channel!(nodes[0], nodes[1], 100000);
let persister = |_: &_| Err(std::io::Error::new(std::io::ErrorKind::Other, "test"));
let event_handler = |_| {};
let bg_processor = BackgroundProcessor::start(persister, event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].peer_manager.clone(), nodes[0].logger.clone());
match bg_processor.join() {
Ok(_) => panic!("Expected error persisting manager"),
Err(e) => {
assert_eq!(e.kind(), std::io::ErrorKind::Other);
assert_eq!(e.get_ref().unwrap().to_string(), "test");
},
}
}
#[test]
fn test_background_event_handling() {
let mut nodes = create_nodes(2, "test_background_event_handling".to_string());
let channel_value = 100000;
let data_dir = nodes[0].persister.get_data_dir();
let persister = move |node: &_| FilesystemPersister::persist_manager(data_dir.clone(), node);
let (sender, receiver) = std::sync::mpsc::sync_channel(1);
let event_handler = move |event| {
sender.send(handle_funding_generation_ready!(event, channel_value)).unwrap();
};
let bg_processor = BackgroundProcessor::start(persister.clone(), event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].peer_manager.clone(), nodes[0].logger.clone());
begin_open_channel!(nodes[0], nodes[1], channel_value);
let (temporary_channel_id, funding_tx) = receiver
.recv_timeout(Duration::from_secs(EVENT_DEADLINE))
.expect("FundingGenerationReady not handled within deadline");
end_open_channel!(nodes[0], nodes[1], temporary_channel_id, funding_tx);
confirm_transaction(&mut nodes[0], &funding_tx);
let as_funding = get_event_msg!(nodes[0], MessageSendEvent::SendFundingLocked, nodes[1].node.get_our_node_id());
confirm_transaction(&mut nodes[1], &funding_tx);
let bs_funding = get_event_msg!(nodes[1], MessageSendEvent::SendFundingLocked, nodes[0].node.get_our_node_id());
nodes[0].node.handle_funding_locked(&nodes[1].node.get_our_node_id(), &bs_funding);
let _as_channel_update = get_event_msg!(nodes[0], MessageSendEvent::SendChannelUpdate, nodes[1].node.get_our_node_id());
nodes[1].node.handle_funding_locked(&nodes[0].node.get_our_node_id(), &as_funding);
let _bs_channel_update = get_event_msg!(nodes[1], MessageSendEvent::SendChannelUpdate, nodes[0].node.get_our_node_id());
assert!(bg_processor.stop().is_ok());
let (sender, receiver) = std::sync::mpsc::sync_channel(1);
let event_handler = move |event| sender.send(event).unwrap();
let bg_processor = BackgroundProcessor::start(persister, event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].peer_manager.clone(), nodes[0].logger.clone());
nodes[0].node.force_close_channel(&nodes[0].node.list_channels()[0].channel_id).unwrap();
let commitment_tx = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap().pop().unwrap();
confirm_transaction_depth(&mut nodes[0], &commitment_tx, BREAKDOWN_TIMEOUT as u32);
let event = receiver
.recv_timeout(Duration::from_secs(EVENT_DEADLINE))
.expect("SpendableOutputs not handled within deadline");
match event {
Event::SpendableOutputs { .. } => {},
_ => panic!("Unexpected event: {:?}", event),
}
assert!(bg_processor.stop().is_ok());
}
}