f - Rename steps to match Build a Node guide
[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::Filter;
23 use lightning::chain::Watch;
24 use lightning::ln::channelmanager;
25 use lightning::ln::channelmanager::{
26         BestBlock, ChainParameters, ChannelManagerReadArgs, SimpleArcChannelManager,
27 };
28 use lightning::ln::peer_handler::{MessageHandler, SimpleArcPeerManager};
29 use lightning::ln::{PaymentHash, PaymentPreimage, PaymentSecret};
30 use lightning::routing::network_graph::NetGraphMsgHandler;
31 use lightning::util::config::UserConfig;
32 use lightning::util::events::Event;
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::hash_map::Entry;
43 use std::collections::HashMap;
44 use std::fmt;
45 use std::fs;
46 use std::fs::File;
47 use std::io;
48 use std::io::Write;
49 use std::ops::Deref;
50 use std::path::Path;
51 use std::sync::{Arc, Mutex};
52 use std::time::{Duration, SystemTime};
53
54 pub(crate) enum HTLCStatus {
55         Pending,
56         Succeeded,
57         Failed,
58 }
59
60 pub(crate) struct MillisatAmount(Option<u64>);
61
62 impl fmt::Display for MillisatAmount {
63         fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
64                 match self.0 {
65                         Some(amt) => write!(f, "{}", amt),
66                         None => write!(f, "unknown"),
67                 }
68         }
69 }
70
71 pub(crate) struct PaymentInfo {
72         preimage: Option<PaymentPreimage>,
73         secret: Option<PaymentSecret>,
74         status: HTLCStatus,
75         amt_msat: MillisatAmount,
76 }
77
78 pub(crate) type PaymentInfoStorage = Arc<Mutex<HashMap<PaymentHash, PaymentInfo>>>;
79
80 type ChainMonitor = chainmonitor::ChainMonitor<
81         InMemorySigner,
82         Arc<dyn Filter + Send + Sync>,
83         Arc<BitcoindClient>,
84         Arc<BitcoindClient>,
85         Arc<FilesystemLogger>,
86         Arc<FilesystemPersister>,
87 >;
88
89 pub(crate) type PeerManager = SimpleArcPeerManager<
90         SocketDescriptor,
91         ChainMonitor,
92         BitcoindClient,
93         BitcoindClient,
94         dyn chain::Access + Send + Sync,
95         FilesystemLogger,
96 >;
97
98 pub(crate) type ChannelManager =
99         SimpleArcChannelManager<ChainMonitor, BitcoindClient, BitcoindClient, FilesystemLogger>;
100
101 async fn handle_ldk_events(
102         channel_manager: Arc<ChannelManager>, bitcoind_client: Arc<BitcoindClient>,
103         keys_manager: Arc<KeysManager>, inbound_payments: PaymentInfoStorage,
104         outbound_payments: PaymentInfoStorage, network: Network, event: Event,
105 ) {
106         match event {
107                 Event::FundingGenerationReady {
108                         temporary_channel_id,
109                         channel_value_satoshis,
110                         output_script,
111                         ..
112                 } => {
113                         // Construct the raw transaction with one output, that is paid the amount of the
114                         // channel.
115                         let addr = WitnessProgram::from_scriptpubkey(
116                                 &output_script[..],
117                                 match network {
118                                         Network::Bitcoin => bitcoin_bech32::constants::Network::Bitcoin,
119                                         Network::Testnet => bitcoin_bech32::constants::Network::Testnet,
120                                         Network::Regtest => bitcoin_bech32::constants::Network::Regtest,
121                                         Network::Signet => panic!("Signet unsupported"),
122                                 },
123                         )
124                         .expect("Lightning funding tx should always be to a SegWit output")
125                         .to_address();
126                         let mut outputs = vec![HashMap::with_capacity(1)];
127                         outputs[0].insert(addr, channel_value_satoshis as f64 / 100_000_000.0);
128                         let raw_tx = bitcoind_client.create_raw_transaction(outputs).await;
129
130                         // Have your wallet put the inputs into the transaction such that the output is
131                         // satisfied.
132                         let funded_tx = bitcoind_client.fund_raw_transaction(raw_tx).await;
133                         let change_output_position = funded_tx.changepos;
134                         assert!(change_output_position == 0 || change_output_position == 1);
135
136                         // Sign the final funding transaction and broadcast it.
137                         let signed_tx = bitcoind_client.sign_raw_transaction_with_wallet(funded_tx.hex).await;
138                         assert_eq!(signed_tx.complete, true);
139                         let final_tx: Transaction =
140                                 encode::deserialize(&hex_utils::to_vec(&signed_tx.hex).unwrap()).unwrap();
141                         // Give the funding transaction back to LDK for opening the channel.
142                         channel_manager.funding_transaction_generated(&temporary_channel_id, final_tx).unwrap();
143                 }
144                 Event::PaymentReceived { payment_hash, payment_preimage, payment_secret, amt, .. } => {
145                         let mut payments = inbound_payments.lock().unwrap();
146                         let status = match channel_manager.claim_funds(payment_preimage.unwrap()) {
147                                 true => {
148                                         println!(
149                                                 "\nEVENT: received payment from payment hash {} of {} millisatoshis",
150                                                 hex_utils::hex_str(&payment_hash.0),
151                                                 amt
152                                         );
153                                         print!("> ");
154                                         io::stdout().flush().unwrap();
155                                         HTLCStatus::Succeeded
156                                 }
157                                 _ => HTLCStatus::Failed,
158                         };
159                         match payments.entry(payment_hash) {
160                                 Entry::Occupied(mut e) => {
161                                         let payment = e.get_mut();
162                                         payment.status = status;
163                                         payment.preimage = Some(payment_preimage.unwrap());
164                                         payment.secret = Some(payment_secret);
165                                 }
166                                 Entry::Vacant(e) => {
167                                         e.insert(PaymentInfo {
168                                                 preimage: Some(payment_preimage.unwrap()),
169                                                 secret: Some(payment_secret),
170                                                 status,
171                                                 amt_msat: MillisatAmount(Some(amt)),
172                                         });
173                                 }
174                         }
175                 }
176                 Event::PaymentSent { payment_preimage } => {
177                         let hashed = PaymentHash(Sha256::hash(&payment_preimage.0).into_inner());
178                         let mut payments = outbound_payments.lock().unwrap();
179                         for (payment_hash, payment) in payments.iter_mut() {
180                                 if *payment_hash == hashed {
181                                         payment.preimage = Some(payment_preimage);
182                                         payment.status = HTLCStatus::Succeeded;
183                                         println!(
184                                                 "\nEVENT: successfully sent payment of {} millisatoshis from \
185                                                                  payment hash {:?} with preimage {:?}",
186                                                 payment.amt_msat,
187                                                 hex_utils::hex_str(&payment_hash.0),
188                                                 hex_utils::hex_str(&payment_preimage.0)
189                                         );
190                                         print!("> ");
191                                         io::stdout().flush().unwrap();
192                                 }
193                         }
194                 }
195                 Event::PaymentFailed { payment_hash, rejected_by_dest } => {
196                         print!(
197                                 "\nEVENT: Failed to send payment to payment hash {:?}: ",
198                                 hex_utils::hex_str(&payment_hash.0)
199                         );
200                         if rejected_by_dest {
201                                 println!("re-attempting the payment will not succeed");
202                         } else {
203                                 println!("payment may be retried");
204                         }
205                         print!("> ");
206                         io::stdout().flush().unwrap();
207
208                         let mut payments = outbound_payments.lock().unwrap();
209                         if payments.contains_key(&payment_hash) {
210                                 let payment = payments.get_mut(&payment_hash).unwrap();
211                                 payment.status = HTLCStatus::Failed;
212                         }
213                 }
214                 Event::PendingHTLCsForwardable { time_forwardable } => {
215                         let forwarding_channel_manager = channel_manager.clone();
216                         tokio::spawn(async move {
217                                 let min = time_forwardable.as_millis() as u64;
218                                 let millis_to_sleep = thread_rng().gen_range(min, min * 5) as u64;
219                                 tokio::time::sleep(Duration::from_millis(millis_to_sleep)).await;
220                                 forwarding_channel_manager.process_pending_htlc_forwards();
221                         });
222                 }
223                 Event::SpendableOutputs { outputs } => {
224                         let destination_address = bitcoind_client.get_new_address().await;
225                         let output_descriptors = &outputs.iter().map(|a| a).collect::<Vec<_>>();
226                         let tx_feerate =
227                                 bitcoind_client.get_est_sat_per_1000_weight(ConfirmationTarget::Normal);
228                         let spending_tx = keys_manager
229                                 .spend_spendable_outputs(
230                                         output_descriptors,
231                                         Vec::new(),
232                                         destination_address.script_pubkey(),
233                                         tx_feerate,
234                                         &Secp256k1::new(),
235                                 )
236                                 .unwrap();
237                         bitcoind_client.broadcast_transaction(&spending_tx);
238                 }
239         }
240 }
241
242 async fn start_ldk() {
243         let args = match cli::parse_startup_args() {
244                 Ok(user_args) => user_args,
245                 Err(()) => return,
246         };
247
248         // Initialize the LDK data directory if necessary.
249         let ldk_data_dir = format!("{}/.ldk", args.ldk_storage_dir_path);
250         fs::create_dir_all(ldk_data_dir.clone()).unwrap();
251
252         // Initialize our bitcoind client.
253         let bitcoind_client = match BitcoindClient::new(
254                 args.bitcoind_rpc_host.clone(),
255                 args.bitcoind_rpc_port,
256                 args.bitcoind_rpc_username.clone(),
257                 args.bitcoind_rpc_password.clone(),
258         )
259         .await
260         {
261                 Ok(client) => Arc::new(client),
262                 Err(e) => {
263                         println!("Failed to connect to bitcoind client: {}", e);
264                         return;
265                 }
266         };
267
268         // Check that the bitcoind we've connected to is running the network we expect
269         let bitcoind_chain = bitcoind_client.get_blockchain_info().await.chain;
270         if bitcoind_chain
271                 != match args.network {
272                         bitcoin::Network::Bitcoin => "main",
273                         bitcoin::Network::Testnet => "test",
274                         bitcoin::Network::Regtest => "regtest",
275                         bitcoin::Network::Signet => "signet",
276                 } {
277                 println!(
278                         "Chain argument ({}) didn't match bitcoind chain ({})",
279                         args.network, bitcoind_chain
280                 );
281                 return;
282         }
283
284         // ## Setup
285         // Step 1: Initialize the FeeEstimator
286
287         // BitcoindClient implements the FeeEstimator trait, so it'll act as our fee estimator.
288         let fee_estimator = bitcoind_client.clone();
289
290         // Step 2: Initialize the Logger
291         let logger = Arc::new(FilesystemLogger::new(ldk_data_dir.clone()));
292
293         // Step 3: Initialize the BroadcasterInterface
294
295         // BitcoindClient implements the BroadcasterInterface trait, so it'll act as our transaction
296         // broadcaster.
297         let broadcaster = bitcoind_client.clone();
298
299         // Step 4: Initialize Persist
300         let persister = Arc::new(FilesystemPersister::new(ldk_data_dir.clone()));
301
302         // Step 5: Initialize the ChainMonitor
303         let chain_monitor: Arc<ChainMonitor> = Arc::new(chainmonitor::ChainMonitor::new(
304                 None,
305                 broadcaster.clone(),
306                 logger.clone(),
307                 fee_estimator.clone(),
308                 persister.clone(),
309         ));
310
311         // Step 6: Initialize the KeysManager
312
313         // The key seed that we use to derive the node privkey (that corresponds to the node pubkey) and
314         // other secret key material.
315         let keys_seed_path = format!("{}/keys_seed", ldk_data_dir.clone());
316         let keys_seed = if let Ok(seed) = fs::read(keys_seed_path.clone()) {
317                 assert_eq!(seed.len(), 32);
318                 let mut key = [0; 32];
319                 key.copy_from_slice(&seed);
320                 key
321         } else {
322                 let mut key = [0; 32];
323                 thread_rng().fill_bytes(&mut key);
324                 match File::create(keys_seed_path.clone()) {
325                         Ok(mut f) => {
326                                 f.write_all(&key).expect("Failed to write node keys seed to disk");
327                                 f.sync_all().expect("Failed to sync node keys seed to disk");
328                         }
329                         Err(e) => {
330                                 println!("ERROR: Unable to create keys seed file {}: {}", keys_seed_path, e);
331                                 return;
332                         }
333                 }
334                 key
335         };
336         let cur = SystemTime::now().duration_since(SystemTime::UNIX_EPOCH).unwrap();
337         let keys_manager = Arc::new(KeysManager::new(&keys_seed, cur.as_secs(), cur.subsec_nanos()));
338
339         // Step 7: Read ChannelMonitor state from disk
340         let mut channelmonitors = persister.read_channelmonitors(keys_manager.clone()).unwrap();
341
342         // Step 8: Initialize the ChannelManager
343         let user_config = UserConfig::default();
344         let mut restarting_node = true;
345         let (channel_manager_blockhash, mut channel_manager) = {
346                 if let Ok(mut f) = fs::File::open(format!("{}/manager", ldk_data_dir.clone())) {
347                         let mut channel_monitor_mut_references = Vec::new();
348                         for (_, channel_monitor) in channelmonitors.iter_mut() {
349                                 channel_monitor_mut_references.push(channel_monitor);
350                         }
351                         let read_args = ChannelManagerReadArgs::new(
352                                 keys_manager.clone(),
353                                 fee_estimator.clone(),
354                                 chain_monitor.clone(),
355                                 broadcaster.clone(),
356                                 logger.clone(),
357                                 user_config,
358                                 channel_monitor_mut_references,
359                         );
360                         <(BlockHash, ChannelManager)>::read(&mut f, read_args).unwrap()
361                 } else {
362                         // We're starting a fresh node.
363                         restarting_node = false;
364                         let getinfo_resp = bitcoind_client.get_blockchain_info().await;
365
366                         let chain_params = ChainParameters {
367                                 network: args.network,
368                                 best_block: BestBlock::new(
369                                         getinfo_resp.latest_blockhash,
370                                         getinfo_resp.latest_height as u32,
371                                 ),
372                         };
373                         let fresh_channel_manager = channelmanager::ChannelManager::new(
374                                 fee_estimator.clone(),
375                                 chain_monitor.clone(),
376                                 broadcaster.clone(),
377                                 logger.clone(),
378                                 keys_manager.clone(),
379                                 user_config,
380                                 chain_params,
381                         );
382                         (getinfo_resp.latest_blockhash, fresh_channel_manager)
383                 }
384         };
385
386         // Step 9: Sync ChannelMonitors and ChannelManager to chain tip
387         let mut chain_listener_channel_monitors = Vec::new();
388         let mut cache = UnboundedCache::new();
389         let mut chain_tip: Option<poll::ValidatedBlockHeader> = None;
390         if restarting_node {
391                 let mut chain_listeners =
392                         vec![(channel_manager_blockhash, &mut channel_manager as &mut dyn chain::Listen)];
393
394                 for (blockhash, channel_monitor) in channelmonitors.drain(..) {
395                         let outpoint = channel_monitor.get_funding_txo().0;
396                         chain_listener_channel_monitors.push((
397                                 blockhash,
398                                 (channel_monitor, broadcaster.clone(), fee_estimator.clone(), logger.clone()),
399                                 outpoint,
400                         ));
401                 }
402
403                 for monitor_listener_info in chain_listener_channel_monitors.iter_mut() {
404                         chain_listeners.push((
405                                 monitor_listener_info.0,
406                                 &mut monitor_listener_info.1 as &mut dyn chain::Listen,
407                         ));
408                 }
409                 chain_tip = Some(
410                         init::synchronize_listeners(
411                                 &mut bitcoind_client.deref(),
412                                 args.network,
413                                 &mut cache,
414                                 chain_listeners,
415                         )
416                         .await
417                         .unwrap(),
418                 );
419         }
420
421         // Step 10: Give ChannelMonitors to ChainMonitor
422         for item in chain_listener_channel_monitors.drain(..) {
423                 let channel_monitor = item.1 .0;
424                 let funding_outpoint = item.2;
425                 chain_monitor.watch_channel(funding_outpoint, channel_monitor).unwrap();
426         }
427
428         // Step 11: Optional: Initialize the NetGraphMsgHandler
429         // XXX persist routing data
430         let genesis = genesis_block(args.network).header.block_hash();
431         let router = Arc::new(NetGraphMsgHandler::new(
432                 genesis,
433                 None::<Arc<dyn chain::Access + Send + Sync>>,
434                 logger.clone(),
435         ));
436
437         // Step 12: Initialize the PeerManager
438         let channel_manager: Arc<ChannelManager> = Arc::new(channel_manager);
439         let mut ephemeral_bytes = [0; 32];
440         rand::thread_rng().fill_bytes(&mut ephemeral_bytes);
441         let lightning_msg_handler =
442                 MessageHandler { chan_handler: channel_manager.clone(), route_handler: router.clone() };
443         let peer_manager: Arc<PeerManager> = Arc::new(PeerManager::new(
444                 lightning_msg_handler,
445                 keys_manager.get_node_secret(),
446                 &ephemeral_bytes,
447                 logger.clone(),
448         ));
449
450         // ## Running LDK
451         // Step 13: Initialize networking
452
453         let peer_manager_connection_handler = peer_manager.clone();
454         let listening_port = args.ldk_peer_listening_port;
455         tokio::spawn(async move {
456                 let listener = tokio::net::TcpListener::bind(format!("0.0.0.0:{}", listening_port))
457                         .await
458                         .expect("Failed to bind to listen port - is something else already listening on it?");
459                 loop {
460                         let peer_mgr = peer_manager_connection_handler.clone();
461                         let tcp_stream = listener.accept().await.unwrap().0;
462                         tokio::spawn(async move {
463                                 lightning_net_tokio::setup_inbound(
464                                         peer_mgr.clone(),
465                                         tcp_stream.into_std().unwrap(),
466                                 )
467                                 .await;
468                         });
469                 }
470         });
471
472         // Step 14: Connect and Disconnect Blocks
473         if chain_tip.is_none() {
474                 chain_tip =
475                         Some(init::validate_best_block_header(&mut bitcoind_client.deref()).await.unwrap());
476         }
477         let channel_manager_listener = channel_manager.clone();
478         let chain_monitor_listener = chain_monitor.clone();
479         let bitcoind_block_source = bitcoind_client.clone();
480         let network = args.network;
481         tokio::spawn(async move {
482                 let mut derefed = bitcoind_block_source.deref();
483                 let chain_poller = poll::ChainPoller::new(&mut derefed, network);
484                 let chain_listener = (chain_monitor_listener, channel_manager_listener);
485                 let mut spv_client =
486                         SpvClient::new(chain_tip.unwrap(), chain_poller, &mut cache, &chain_listener);
487                 loop {
488                         spv_client.poll_best_tip().await.unwrap();
489                         tokio::time::sleep(Duration::from_secs(1)).await;
490                 }
491         });
492
493         // Step 15: Handle LDK Events
494         let channel_manager_event_listener = channel_manager.clone();
495         let keys_manager_listener = keys_manager.clone();
496         // TODO: persist payment info to disk
497         let inbound_payments: PaymentInfoStorage = Arc::new(Mutex::new(HashMap::new()));
498         let outbound_payments: PaymentInfoStorage = Arc::new(Mutex::new(HashMap::new()));
499         let inbound_pmts_for_events = inbound_payments.clone();
500         let outbound_pmts_for_events = outbound_payments.clone();
501         let network = args.network;
502         let bitcoind_rpc = bitcoind_client.clone();
503         let handle = tokio::runtime::Handle::current();
504         let event_handler = move |event| {
505                 handle.block_on(handle_ldk_events(
506                         channel_manager_event_listener.clone(),
507                         bitcoind_rpc.clone(),
508                         keys_manager_listener.clone(),
509                         inbound_pmts_for_events.clone(),
510                         outbound_pmts_for_events.clone(),
511                         network,
512                         event,
513                 ))
514         };
515         // Step 16: Persist ChannelManager
516         let data_dir = ldk_data_dir.clone();
517         let persist_channel_manager_callback =
518                 move |node: &ChannelManager| FilesystemPersister::persist_manager(data_dir.clone(), &*node);
519         // Step 17: Background Processing
520         BackgroundProcessor::start(
521                 persist_channel_manager_callback,
522                 event_handler,
523                 chain_monitor.clone(),
524                 channel_manager.clone(),
525                 peer_manager.clone(),
526                 logger.clone(),
527         );
528
529         // Reconnect to channel peers if possible.
530         let peer_data_path = format!("{}/channel_peer_data", ldk_data_dir.clone());
531         match disk::read_channel_peer_data(Path::new(&peer_data_path)) {
532                 Ok(mut info) => {
533                         for (pubkey, peer_addr) in info.drain() {
534                                 for chan_info in channel_manager.list_channels() {
535                                         if pubkey == chan_info.remote_network_id {
536                                                 let _ =
537                                                         cli::connect_peer_if_necessary(pubkey, peer_addr, peer_manager.clone())
538                                                                 .await;
539                                         }
540                                 }
541                         }
542                 }
543                 Err(e) => println!("ERROR: errored reading channel peer info from disk: {:?}", e),
544         }
545
546         // Regularly broadcast our node_announcement. This is only required (or possible) if we have
547         // some public channels, and is only useful if we have public listen address(es) to announce.
548         // In a production environment, this should occur only after the announcement of new channels
549         // to avoid churn in the global network graph.
550         let chan_manager = Arc::clone(&channel_manager);
551         let network = args.network;
552         if args.ldk_announced_listen_addr.is_some() {
553                 tokio::spawn(async move {
554                         let mut interval = tokio::time::interval(Duration::from_secs(60));
555                         loop {
556                                 interval.tick().await;
557                                 chan_manager.broadcast_node_announcement(
558                                         [0; 3],
559                                         args.ldk_announced_node_name,
560                                         vec![args.ldk_announced_listen_addr.as_ref().unwrap().clone()],
561                                 );
562                         }
563                 });
564         }
565
566         // Start the CLI.
567         cli::poll_for_user_input(
568                 peer_manager.clone(),
569                 channel_manager.clone(),
570                 keys_manager.clone(),
571                 router.clone(),
572                 inbound_payments,
573                 outbound_payments,
574                 ldk_data_dir.clone(),
575                 logger.clone(),
576                 network,
577         )
578         .await;
579 }
580
581 #[tokio::main]
582 pub async fn main() {
583         start_ldk().await;
584 }