5f5dc0af87324ba4bf416829d8ea2fa1446036b0
[ldk-sample] / src / main.rs
1 pub mod bitcoind_client;
2 mod cli;
3 mod convert;
4 mod disk;
5 mod hex_utils;
6
7 use crate::bitcoind_client::BitcoindClient;
8 use crate::disk::FilesystemLogger;
9 use bitcoin::blockdata::constants::genesis_block;
10 use bitcoin::blockdata::transaction::Transaction;
11 use bitcoin::consensus::encode;
12 use bitcoin::hashes::sha256::Hash as Sha256;
13 use bitcoin::hashes::Hash;
14 use bitcoin::network::constants::Network;
15 use bitcoin::secp256k1::Secp256k1;
16 use bitcoin::BlockHash;
17 use bitcoin_bech32::WitnessProgram;
18 use lightning::chain;
19 use lightning::chain::chaininterface::{BroadcasterInterface, ConfirmationTarget, FeeEstimator};
20 use lightning::chain::chainmonitor;
21 use lightning::chain::keysinterface::{InMemorySigner, KeysInterface, KeysManager};
22 use lightning::chain::transaction::OutPoint;
23 use lightning::chain::Filter;
24 use lightning::chain::Watch;
25 use lightning::ln::channelmanager;
26 use lightning::ln::channelmanager::{
27         ChainParameters, ChannelManagerReadArgs, PaymentHash, PaymentPreimage, SimpleArcChannelManager,
28 };
29 use lightning::ln::peer_handler::{MessageHandler, SimpleArcPeerManager};
30 use lightning::routing::network_graph::NetGraphMsgHandler;
31 use lightning::util::config::UserConfig;
32 use lightning::util::events::{Event, EventsProvider};
33 use lightning::util::ser::ReadableArgs;
34 use lightning_background_processor::BackgroundProcessor;
35 use lightning_block_sync::init;
36 use lightning_block_sync::poll;
37 use lightning_block_sync::SpvClient;
38 use lightning_block_sync::UnboundedCache;
39 use lightning_net_tokio::SocketDescriptor;
40 use lightning_persister::FilesystemPersister;
41 use rand::{thread_rng, Rng};
42 use std::collections::HashMap;
43 use std::fmt;
44 use std::fs;
45 use std::fs::File;
46 use std::io;
47 use std::io::Write;
48 use std::ops::Deref;
49 use std::path::Path;
50 use std::sync::{Arc, Mutex};
51 use std::time::{Duration, SystemTime};
52 use tokio::sync::mpsc;
53
54 #[derive(PartialEq)]
55 pub(crate) enum HTLCDirection {
56         Inbound,
57         Outbound,
58 }
59
60 pub(crate) enum HTLCStatus {
61         Pending,
62         Succeeded,
63         Failed,
64 }
65
66 pub(crate) struct SatoshiAmount(Option<u64>);
67
68 impl fmt::Display for SatoshiAmount {
69         fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
70                 match self.0 {
71                         Some(amt) => write!(f, "{}", amt),
72                         None => write!(f, "unknown"),
73                 }
74         }
75 }
76
77 pub(crate) type PaymentInfoStorage = Arc<
78         Mutex<
79                 HashMap<PaymentHash, (Option<PaymentPreimage>, HTLCDirection, HTLCStatus, SatoshiAmount)>,
80         >,
81 >;
82
83 type ChainMonitor = chainmonitor::ChainMonitor<
84         InMemorySigner,
85         Arc<dyn Filter>,
86         Arc<BitcoindClient>,
87         Arc<BitcoindClient>,
88         Arc<FilesystemLogger>,
89         Arc<FilesystemPersister>,
90 >;
91
92 pub(crate) type PeerManager = SimpleArcPeerManager<
93         SocketDescriptor,
94         ChainMonitor,
95         BitcoindClient,
96         BitcoindClient,
97         dyn chain::Access,
98         FilesystemLogger,
99 >;
100
101 pub(crate) type ChannelManager =
102         SimpleArcChannelManager<ChainMonitor, BitcoindClient, BitcoindClient, FilesystemLogger>;
103
104 async fn handle_ldk_events(
105         peer_manager: Arc<PeerManager>, channel_manager: Arc<ChannelManager>,
106         chain_monitor: Arc<ChainMonitor>, bitcoind_client: Arc<BitcoindClient>,
107         keys_manager: Arc<KeysManager>, payment_storage: PaymentInfoStorage, network: Network,
108 ) {
109         let mut pending_txs: HashMap<OutPoint, Transaction> = HashMap::new();
110         loop {
111                 peer_manager.process_events();
112                 let loop_channel_manager = channel_manager.clone();
113                 let mut events = channel_manager.get_and_clear_pending_events();
114                 events.append(&mut chain_monitor.get_and_clear_pending_events());
115                 for event in events {
116                         match event {
117                                 Event::FundingGenerationReady {
118                                         temporary_channel_id,
119                                         channel_value_satoshis,
120                                         output_script,
121                                         ..
122                                 } => {
123                                         // Construct the raw transaction with one output, that is paid the amount of the
124                                         // channel.
125                                         let addr = WitnessProgram::from_scriptpubkey(
126                                                 &output_script[..],
127                                                 match network {
128                                                         Network::Bitcoin => bitcoin_bech32::constants::Network::Bitcoin,
129                                                         Network::Testnet => bitcoin_bech32::constants::Network::Testnet,
130                                                         Network::Regtest => bitcoin_bech32::constants::Network::Regtest,
131                                                         Network::Signet => panic!("Signet unsupported"),
132                                                 },
133                                         )
134                                         .expect("Lightning funding tx should always be to a SegWit output")
135                                         .to_address();
136                                         let mut outputs = vec![HashMap::with_capacity(1)];
137                                         outputs[0].insert(addr, channel_value_satoshis as f64 / 100_000_000.0);
138                                         let raw_tx = bitcoind_client.create_raw_transaction(outputs).await;
139
140                                         // Have your wallet put the inputs into the transaction such that the output is
141                                         // satisfied.
142                                         let funded_tx = bitcoind_client.fund_raw_transaction(raw_tx).await;
143                                         let change_output_position = funded_tx.changepos;
144                                         assert!(change_output_position == 0 || change_output_position == 1);
145
146                                         // Sign the final funding transaction and broadcast it.
147                                         let signed_tx =
148                                                 bitcoind_client.sign_raw_transaction_with_wallet(funded_tx.hex).await;
149                                         assert_eq!(signed_tx.complete, true);
150                                         let final_tx: Transaction =
151                                                 encode::deserialize(&hex_utils::to_vec(&signed_tx.hex).unwrap()).unwrap();
152                                         let outpoint = OutPoint {
153                                                 txid: final_tx.txid(),
154                                                 index: if change_output_position == 0 { 1 } else { 0 },
155                                         };
156                                         // Give the funding transaction back to LDK for opening the channel.
157                                         loop_channel_manager
158                                                 .funding_transaction_generated(&temporary_channel_id, outpoint);
159                                         pending_txs.insert(outpoint, final_tx);
160                                 }
161                                 Event::FundingBroadcastSafe { funding_txo, .. } => {
162                                         let funding_tx = pending_txs.remove(&funding_txo).unwrap();
163                                         bitcoind_client.broadcast_transaction(&funding_tx);
164                                         println!("\nEVENT: broadcasted funding transaction");
165                                         print!("> ");
166                                         io::stdout().flush().unwrap();
167                                 }
168                                 Event::PaymentReceived { payment_hash, payment_secret, amt: amt_msat } => {
169                                         let mut payments = payment_storage.lock().unwrap();
170                                         if let Some((Some(preimage), _, _, _)) = payments.get(&payment_hash) {
171                                                 assert!(loop_channel_manager.claim_funds(
172                                                         preimage.clone(),
173                                                         &payment_secret,
174                                                         amt_msat
175                                                 ));
176                                                 println!(
177                                                         "\nEVENT: received payment from payment_hash {} of {} satoshis",
178                                                         hex_utils::hex_str(&payment_hash.0),
179                                                         amt_msat / 1000
180                                                 );
181                                                 print!("> ");
182                                                 io::stdout().flush().unwrap();
183                                                 let (_, _, ref mut status, _) = payments.get_mut(&payment_hash).unwrap();
184                                                 *status = HTLCStatus::Succeeded;
185                                         } else {
186                                                 println!("\nERROR: we received a payment but didn't know the preimage");
187                                                 print!("> ");
188                                                 io::stdout().flush().unwrap();
189                                                 loop_channel_manager.fail_htlc_backwards(&payment_hash, &payment_secret);
190                                                 payments.insert(
191                                                         payment_hash,
192                                                         (None, HTLCDirection::Inbound, HTLCStatus::Failed, SatoshiAmount(None)),
193                                                 );
194                                         }
195                                 }
196                                 Event::PaymentSent { payment_preimage } => {
197                                         let hashed = PaymentHash(Sha256::hash(&payment_preimage.0).into_inner());
198                                         let mut payments = payment_storage.lock().unwrap();
199                                         for (payment_hash, (preimage_option, _, status, amt_sat)) in payments.iter_mut()
200                                         {
201                                                 if *payment_hash == hashed {
202                                                         *preimage_option = Some(payment_preimage);
203                                                         *status = HTLCStatus::Succeeded;
204                                                         println!(
205                                                                 "\nEVENT: successfully sent payment of {} satoshis from \
206                                          payment hash {:?} with preimage {:?}",
207                                                                 amt_sat,
208                                                                 hex_utils::hex_str(&payment_hash.0),
209                                                                 hex_utils::hex_str(&payment_preimage.0)
210                                                         );
211                                                         print!("> ");
212                                                         io::stdout().flush().unwrap();
213                                                 }
214                                         }
215                                 }
216                                 Event::PaymentFailed { payment_hash, rejected_by_dest } => {
217                                         print!(
218                                                 "\nEVENT: Failed to send payment to payment hash {:?}: ",
219                                                 hex_utils::hex_str(&payment_hash.0)
220                                         );
221                                         if rejected_by_dest {
222                                                 println!("rejected by destination node");
223                                         } else {
224                                                 println!("route failed");
225                                         }
226                                         print!("> ");
227                                         io::stdout().flush().unwrap();
228
229                                         let mut payments = payment_storage.lock().unwrap();
230                                         if payments.contains_key(&payment_hash) {
231                                                 let (_, _, ref mut status, _) = payments.get_mut(&payment_hash).unwrap();
232                                                 *status = HTLCStatus::Failed;
233                                         }
234                                 }
235                                 Event::PendingHTLCsForwardable { time_forwardable } => {
236                                         let forwarding_channel_manager = loop_channel_manager.clone();
237                                         tokio::spawn(async move {
238                                                 let min = time_forwardable.as_millis() as u64;
239                                                 let millis_to_sleep = thread_rng().gen_range(min, min * 5) as u64;
240                                                 tokio::time::sleep(Duration::from_millis(millis_to_sleep)).await;
241                                                 forwarding_channel_manager.process_pending_htlc_forwards();
242                                         });
243                                 }
244                                 Event::SpendableOutputs { outputs } => {
245                                         let destination_address = bitcoind_client.get_new_address().await;
246                                         let output_descriptors = &outputs.iter().map(|a| a).collect::<Vec<_>>();
247                                         let tx_feerate =
248                                                 bitcoind_client.get_est_sat_per_1000_weight(ConfirmationTarget::Normal);
249                                         let spending_tx = keys_manager
250                                                 .spend_spendable_outputs(
251                                                         output_descriptors,
252                                                         Vec::new(),
253                                                         destination_address.script_pubkey(),
254                                                         tx_feerate,
255                                                         &Secp256k1::new(),
256                                                 )
257                                                 .unwrap();
258                                         bitcoind_client.broadcast_transaction(&spending_tx);
259                                 }
260                         }
261                 }
262                 tokio::time::sleep(Duration::from_secs(1)).await;
263         }
264 }
265
266 async fn start_ldk() {
267         let args = match cli::parse_startup_args() {
268                 Ok(user_args) => user_args,
269                 Err(()) => return,
270         };
271
272         // Initialize the LDK data directory if necessary.
273         let ldk_data_dir = format!("{}/.ldk", args.ldk_storage_dir_path);
274         fs::create_dir_all(ldk_data_dir.clone()).unwrap();
275
276         // Initialize our bitcoind client.
277         let bitcoind_client = match BitcoindClient::new(
278                 args.bitcoind_rpc_host.clone(),
279                 args.bitcoind_rpc_port,
280                 args.bitcoind_rpc_username.clone(),
281                 args.bitcoind_rpc_password.clone(),
282         )
283         .await
284         {
285                 Ok(client) => Arc::new(client),
286                 Err(e) => {
287                         println!("Failed to connect to bitcoind client: {}", e);
288                         return;
289                 }
290         };
291
292         // ## Setup
293         // Step 1: Initialize the FeeEstimator
294
295         // BitcoindClient implements the FeeEstimator trait, so it'll act as our fee estimator.
296         let fee_estimator = bitcoind_client.clone();
297
298         // Step 2: Initialize the Logger
299         let logger = Arc::new(FilesystemLogger::new(ldk_data_dir.clone()));
300
301         // Step 3: Initialize the BroadcasterInterface
302
303         // BitcoindClient implements the BroadcasterInterface trait, so it'll act as our transaction
304         // broadcaster.
305         let broadcaster = bitcoind_client.clone();
306
307         // Step 4: Initialize Persist
308         let persister = Arc::new(FilesystemPersister::new(ldk_data_dir.clone()));
309
310         // Step 5: Initialize the ChainMonitor
311         let chain_monitor: Arc<ChainMonitor> = Arc::new(chainmonitor::ChainMonitor::new(
312                 None,
313                 broadcaster.clone(),
314                 logger.clone(),
315                 fee_estimator.clone(),
316                 persister.clone(),
317         ));
318
319         // Step 6: Initialize the KeysManager
320
321         // The key seed that we use to derive the node privkey (that corresponds to the node pubkey) and
322         // other secret key material.
323         let keys_seed_path = format!("{}/keys_seed", ldk_data_dir.clone());
324         let keys_seed = if let Ok(seed) = fs::read(keys_seed_path.clone()) {
325                 assert_eq!(seed.len(), 32);
326                 let mut key = [0; 32];
327                 key.copy_from_slice(&seed);
328                 key
329         } else {
330                 let mut key = [0; 32];
331                 thread_rng().fill_bytes(&mut key);
332                 match File::create(keys_seed_path.clone()) {
333                         Ok(mut f) => {
334                                 f.write_all(&key).expect("Failed to write node keys seed to disk");
335                                 f.sync_all().expect("Failed to sync node keys seed to disk");
336                         }
337                         Err(e) => {
338                                 println!("ERROR: Unable to create keys seed file {}: {}", keys_seed_path, e);
339                                 return;
340                         }
341                 }
342                 key
343         };
344         let cur = SystemTime::now().duration_since(SystemTime::UNIX_EPOCH).unwrap();
345         let keys_manager = Arc::new(KeysManager::new(&keys_seed, cur.as_secs(), cur.subsec_nanos()));
346
347         // Step 7: Read ChannelMonitor state from disk
348         let monitors_path = format!("{}/monitors", ldk_data_dir.clone());
349         let mut outpoint_to_channelmonitor =
350                 disk::read_channelmonitors(monitors_path.to_string(), keys_manager.clone()).unwrap();
351
352         // Step 9: Initialize the ChannelManager
353         let user_config = UserConfig::default();
354         let mut restarting_node = true;
355         let (channel_manager_blockhash, mut channel_manager) = {
356                 if let Ok(mut f) = fs::File::open(format!("{}/manager", ldk_data_dir.clone())) {
357                         let mut channel_monitor_mut_references = Vec::new();
358                         for (_, channel_monitor) in outpoint_to_channelmonitor.iter_mut() {
359                                 channel_monitor_mut_references.push(&mut channel_monitor.1);
360                         }
361                         let read_args = ChannelManagerReadArgs::new(
362                                 keys_manager.clone(),
363                                 fee_estimator.clone(),
364                                 chain_monitor.clone(),
365                                 broadcaster.clone(),
366                                 logger.clone(),
367                                 user_config,
368                                 channel_monitor_mut_references,
369                         );
370                         <(BlockHash, ChannelManager)>::read(&mut f, read_args).unwrap()
371                 } else {
372                         // We're starting a fresh node.
373                         restarting_node = false;
374                         let getinfo_resp = bitcoind_client.get_blockchain_info().await;
375
376                         let chain_params = ChainParameters {
377                                 network: args.network,
378                                 latest_hash: getinfo_resp.latest_blockhash,
379                                 latest_height: getinfo_resp.latest_height,
380                         };
381                         let fresh_channel_manager = channelmanager::ChannelManager::new(
382                                 fee_estimator.clone(),
383                                 chain_monitor.clone(),
384                                 broadcaster.clone(),
385                                 logger.clone(),
386                                 keys_manager.clone(),
387                                 user_config,
388                                 chain_params,
389                         );
390                         (getinfo_resp.latest_blockhash, fresh_channel_manager)
391                 }
392         };
393
394         // Step 10: Sync ChannelMonitors and ChannelManager to chain tip
395         let mut chain_listener_channel_monitors = Vec::new();
396         let mut cache = UnboundedCache::new();
397         let mut chain_tip: Option<poll::ValidatedBlockHeader> = None;
398         if restarting_node {
399                 let mut chain_listeners =
400                         vec![(channel_manager_blockhash, &mut channel_manager as &mut dyn chain::Listen)];
401
402                 for (outpoint, blockhash_and_monitor) in outpoint_to_channelmonitor.drain() {
403                         let blockhash = blockhash_and_monitor.0;
404                         let channel_monitor = blockhash_and_monitor.1;
405                         chain_listener_channel_monitors.push((
406                                 blockhash,
407                                 (channel_monitor, broadcaster.clone(), fee_estimator.clone(), logger.clone()),
408                                 outpoint,
409                         ));
410                 }
411
412                 for monitor_listener_info in chain_listener_channel_monitors.iter_mut() {
413                         chain_listeners.push((
414                                 monitor_listener_info.0,
415                                 &mut monitor_listener_info.1 as &mut dyn chain::Listen,
416                         ));
417                 }
418                 chain_tip = Some(
419                         init::synchronize_listeners(
420                                 &mut bitcoind_client.deref(),
421                                 args.network,
422                                 &mut cache,
423                                 chain_listeners,
424                         )
425                         .await
426                         .unwrap(),
427                 );
428         }
429
430         // Step 11: Give ChannelMonitors to ChainMonitor
431         for item in chain_listener_channel_monitors.drain(..) {
432                 let channel_monitor = item.1 .0;
433                 let funding_outpoint = item.2;
434                 chain_monitor.watch_channel(funding_outpoint, channel_monitor).unwrap();
435         }
436
437         // Step 13: Optional: Initialize the NetGraphMsgHandler
438         // XXX persist routing data
439         let genesis = genesis_block(args.network).header.block_hash();
440         let router =
441                 Arc::new(NetGraphMsgHandler::new(genesis, None::<Arc<dyn chain::Access>>, logger.clone()));
442
443         // Step 14: Initialize the PeerManager
444         let channel_manager: Arc<ChannelManager> = Arc::new(channel_manager);
445         let mut ephemeral_bytes = [0; 32];
446         rand::thread_rng().fill_bytes(&mut ephemeral_bytes);
447         let lightning_msg_handler =
448                 MessageHandler { chan_handler: channel_manager.clone(), route_handler: router.clone() };
449         let peer_manager: Arc<PeerManager> = Arc::new(PeerManager::new(
450                 lightning_msg_handler,
451                 keys_manager.get_node_secret(),
452                 &ephemeral_bytes,
453                 logger.clone(),
454         ));
455
456         // ## Running LDK
457         // Step 16: Initialize Peer Connection Handling
458
459         // We poll for events in handle_ldk_events(..) rather than waiting for them over the
460         // mpsc::channel, so we can leave the event receiver as unused.
461         let (event_ntfn_sender, _event_ntfn_receiver) = mpsc::channel(2);
462         let peer_manager_connection_handler = peer_manager.clone();
463         let event_notifier = event_ntfn_sender.clone();
464         let listening_port = args.ldk_peer_listening_port;
465         tokio::spawn(async move {
466                 let listener = std::net::TcpListener::bind(format!("0.0.0.0:{}", listening_port)).unwrap();
467                 loop {
468                         let tcp_stream = listener.accept().unwrap().0;
469                         lightning_net_tokio::setup_inbound(
470                                 peer_manager_connection_handler.clone(),
471                                 event_notifier.clone(),
472                                 tcp_stream,
473                         )
474                         .await;
475                 }
476         });
477
478         // Step 17: Connect and Disconnect Blocks
479         if chain_tip.is_none() {
480                 chain_tip =
481                         Some(init::validate_best_block_header(&mut bitcoind_client.deref()).await.unwrap());
482         }
483         let channel_manager_listener = channel_manager.clone();
484         let chain_monitor_listener = chain_monitor.clone();
485         let bitcoind_block_source = bitcoind_client.clone();
486         let network = args.network;
487         tokio::spawn(async move {
488                 let mut derefed = bitcoind_block_source.deref();
489                 let chain_poller = poll::ChainPoller::new(&mut derefed, network);
490                 let chain_listener = (chain_monitor_listener, channel_manager_listener);
491                 let mut spv_client =
492                         SpvClient::new(chain_tip.unwrap(), chain_poller, &mut cache, &chain_listener);
493                 loop {
494                         spv_client.poll_best_tip().await.unwrap();
495                         tokio::time::sleep(Duration::from_secs(1)).await;
496                 }
497         });
498
499         // Step 17 & 18: Initialize ChannelManager persistence & Once Per Minute: ChannelManager's
500         // timer_chan_freshness_every_min() and PeerManager's timer_tick_occurred
501         let data_dir = ldk_data_dir.clone();
502         let persist_channel_manager_callback =
503                 move |node: &ChannelManager| FilesystemPersister::persist_manager(data_dir.clone(), &*node);
504         BackgroundProcessor::start(
505                 persist_channel_manager_callback,
506                 channel_manager.clone(),
507                 logger.clone(),
508         );
509
510         let peer_manager_processor = peer_manager.clone();
511         tokio::spawn(async move {
512                 loop {
513                         peer_manager_processor.timer_tick_occurred();
514                         tokio::time::sleep(Duration::from_secs(60)).await;
515                 }
516         });
517
518         // Step 15: Initialize LDK Event Handling
519         let peer_manager_event_listener = peer_manager.clone();
520         let channel_manager_event_listener = channel_manager.clone();
521         let chain_monitor_event_listener = chain_monitor.clone();
522         let keys_manager_listener = keys_manager.clone();
523         let payment_info: PaymentInfoStorage = Arc::new(Mutex::new(HashMap::new()));
524         let payment_info_for_events = payment_info.clone();
525         let network = args.network;
526         let bitcoind_rpc = bitcoind_client.clone();
527         tokio::spawn(async move {
528                 handle_ldk_events(
529                         peer_manager_event_listener,
530                         channel_manager_event_listener,
531                         chain_monitor_event_listener,
532                         bitcoind_rpc,
533                         keys_manager_listener,
534                         payment_info_for_events,
535                         network,
536                 )
537                 .await;
538         });
539
540         // Reconnect to channel peers if possible.
541         let peer_data_path = format!("{}/channel_peer_data", ldk_data_dir.clone());
542         match disk::read_channel_peer_data(Path::new(&peer_data_path)) {
543                 Ok(mut info) => {
544                         for (pubkey, peer_addr) in info.drain() {
545                                 for chan_info in channel_manager.list_channels() {
546                                         if pubkey == chan_info.remote_network_id {
547                                                 let _ = cli::connect_peer_if_necessary(
548                                                         pubkey,
549                                                         peer_addr,
550                                                         peer_manager.clone(),
551                                                         event_ntfn_sender.clone(),
552                                                 );
553                                         }
554                                 }
555                         }
556                 }
557                 Err(e) => println!("ERROR: errored reading channel peer info from disk: {:?}", e),
558         }
559
560         // Start the CLI.
561         cli::poll_for_user_input(
562                 peer_manager.clone(),
563                 channel_manager.clone(),
564                 router.clone(),
565                 payment_info,
566                 keys_manager.get_node_secret(),
567                 event_ntfn_sender,
568                 ldk_data_dir.clone(),
569                 logger.clone(),
570                 args.network,
571         )
572         .await;
573 }
574
575 #[tokio::main]
576 pub async fn main() {
577         start_ldk().await;
578 }