21dfb284a81eeae3e9b1366a41e55fc4cd891378
[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, 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::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 use tokio::sync::mpsc;
54 use tokio::sync::mpsc::Receiver;
55
56 pub(crate) enum HTLCStatus {
57         Pending,
58         Succeeded,
59         Failed,
60 }
61
62 pub(crate) struct MillisatAmount(Option<u64>);
63
64 impl fmt::Display for MillisatAmount {
65         fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
66                 match self.0 {
67                         Some(amt) => write!(f, "{}", amt),
68                         None => write!(f, "unknown"),
69                 }
70         }
71 }
72
73 pub(crate) struct PaymentInfo {
74         preimage: Option<PaymentPreimage>,
75         secret: Option<PaymentSecret>,
76         status: HTLCStatus,
77         amt_msat: MillisatAmount,
78 }
79
80 pub(crate) type PaymentInfoStorage = Arc<Mutex<HashMap<PaymentHash, PaymentInfo>>>;
81
82 type ChainMonitor = chainmonitor::ChainMonitor<
83         InMemorySigner,
84         Arc<dyn Filter + Send + Sync>,
85         Arc<BitcoindClient>,
86         Arc<BitcoindClient>,
87         Arc<FilesystemLogger>,
88         Arc<FilesystemPersister>,
89 >;
90
91 pub(crate) type PeerManager = SimpleArcPeerManager<
92         SocketDescriptor,
93         ChainMonitor,
94         BitcoindClient,
95         BitcoindClient,
96         dyn chain::Access + Send + Sync,
97         FilesystemLogger,
98 >;
99
100 pub(crate) type ChannelManager =
101         SimpleArcChannelManager<ChainMonitor, BitcoindClient, BitcoindClient, FilesystemLogger>;
102
103 async fn handle_ldk_events(
104         channel_manager: Arc<ChannelManager>, chain_monitor: Arc<ChainMonitor>,
105         bitcoind_client: Arc<BitcoindClient>, keys_manager: Arc<KeysManager>,
106         inbound_payments: PaymentInfoStorage, outbound_payments: PaymentInfoStorage, network: Network,
107         mut event_receiver: Receiver<()>,
108 ) {
109         loop {
110                 let received = event_receiver.recv();
111                 if received.await.is_none() {
112                         println!("LDK Event channel closed!");
113                         return;
114                 }
115                 let loop_channel_manager = channel_manager.clone();
116                 let mut events = channel_manager.get_and_clear_pending_events();
117                 events.append(&mut chain_monitor.get_and_clear_pending_events());
118                 for event in events {
119                         match event {
120                                 Event::FundingGenerationReady {
121                                         temporary_channel_id,
122                                         channel_value_satoshis,
123                                         output_script,
124                                         ..
125                                 } => {
126                                         // Construct the raw transaction with one output, that is paid the amount of the
127                                         // channel.
128                                         let addr = WitnessProgram::from_scriptpubkey(
129                                                 &output_script[..],
130                                                 match network {
131                                                         Network::Bitcoin => bitcoin_bech32::constants::Network::Bitcoin,
132                                                         Network::Testnet => bitcoin_bech32::constants::Network::Testnet,
133                                                         Network::Regtest => bitcoin_bech32::constants::Network::Regtest,
134                                                         Network::Signet => panic!("Signet unsupported"),
135                                                 },
136                                         )
137                                         .expect("Lightning funding tx should always be to a SegWit output")
138                                         .to_address();
139                                         let mut outputs = vec![HashMap::with_capacity(1)];
140                                         outputs[0].insert(addr, channel_value_satoshis as f64 / 100_000_000.0);
141                                         let raw_tx = bitcoind_client.create_raw_transaction(outputs).await;
142
143                                         // Have your wallet put the inputs into the transaction such that the output is
144                                         // satisfied.
145                                         let funded_tx = bitcoind_client.fund_raw_transaction(raw_tx).await;
146                                         let change_output_position = funded_tx.changepos;
147                                         assert!(change_output_position == 0 || change_output_position == 1);
148
149                                         // Sign the final funding transaction and broadcast it.
150                                         let signed_tx =
151                                                 bitcoind_client.sign_raw_transaction_with_wallet(funded_tx.hex).await;
152                                         assert_eq!(signed_tx.complete, true);
153                                         let final_tx: Transaction =
154                                                 encode::deserialize(&hex_utils::to_vec(&signed_tx.hex).unwrap()).unwrap();
155                                         // Give the funding transaction back to LDK for opening the channel.
156                                         loop_channel_manager
157                                                 .funding_transaction_generated(&temporary_channel_id, final_tx)
158                                                 .unwrap();
159                                 }
160                                 Event::PaymentReceived {
161                                         payment_hash,
162                                         payment_preimage,
163                                         payment_secret,
164                                         amt,
165                                         ..
166                                 } => {
167                                         let mut payments = inbound_payments.lock().unwrap();
168                                         let status = match loop_channel_manager.claim_funds(payment_preimage.unwrap()) {
169                                                 true => {
170                                                         println!(
171                                                                 "\nEVENT: received payment from payment hash {} of {} millisatoshis",
172                                                                 hex_utils::hex_str(&payment_hash.0),
173                                                                 amt
174                                                         );
175                                                         print!("> ");
176                                                         io::stdout().flush().unwrap();
177                                                         HTLCStatus::Succeeded
178                                                 }
179                                                 _ => HTLCStatus::Failed,
180                                         };
181                                         match payments.entry(payment_hash) {
182                                                 Entry::Occupied(mut e) => {
183                                                         let payment = e.get_mut();
184                                                         payment.status = status;
185                                                         payment.preimage = Some(payment_preimage.unwrap());
186                                                         payment.secret = Some(payment_secret);
187                                                 }
188                                                 Entry::Vacant(e) => {
189                                                         e.insert(PaymentInfo {
190                                                                 preimage: Some(payment_preimage.unwrap()),
191                                                                 secret: Some(payment_secret),
192                                                                 status,
193                                                                 amt_msat: MillisatAmount(Some(amt)),
194                                                         });
195                                                 }
196                                         }
197                                 }
198                                 Event::PaymentSent { payment_preimage } => {
199                                         let hashed = PaymentHash(Sha256::hash(&payment_preimage.0).into_inner());
200                                         let mut payments = outbound_payments.lock().unwrap();
201                                         for (payment_hash, payment) in payments.iter_mut() {
202                                                 if *payment_hash == hashed {
203                                                         payment.preimage = Some(payment_preimage);
204                                                         payment.status = HTLCStatus::Succeeded;
205                                                         println!(
206                                                                 "\nEVENT: successfully sent payment of {} millisatoshis from \
207                                          payment hash {:?} with preimage {:?}",
208                                                                 payment.amt_msat,
209                                                                 hex_utils::hex_str(&payment_hash.0),
210                                                                 hex_utils::hex_str(&payment_preimage.0)
211                                                         );
212                                                         print!("> ");
213                                                         io::stdout().flush().unwrap();
214                                                 }
215                                         }
216                                 }
217                                 Event::PaymentFailed { payment_hash, rejected_by_dest } => {
218                                         print!(
219                                                 "\nEVENT: Failed to send payment to payment hash {:?}: ",
220                                                 hex_utils::hex_str(&payment_hash.0)
221                                         );
222                                         if rejected_by_dest {
223                                                 println!("rejected by destination node");
224                                         } else {
225                                                 println!("route failed");
226                                         }
227                                         print!("> ");
228                                         io::stdout().flush().unwrap();
229
230                                         let mut payments = outbound_payments.lock().unwrap();
231                                         if payments.contains_key(&payment_hash) {
232                                                 let payment = payments.get_mut(&payment_hash).unwrap();
233                                                 payment.status = HTLCStatus::Failed;
234                                         }
235                                 }
236                                 Event::PendingHTLCsForwardable { time_forwardable } => {
237                                         let forwarding_channel_manager = loop_channel_manager.clone();
238                                         tokio::spawn(async move {
239                                                 let min = time_forwardable.as_millis() as u64;
240                                                 let millis_to_sleep = thread_rng().gen_range(min, min * 5) as u64;
241                                                 tokio::time::sleep(Duration::from_millis(millis_to_sleep)).await;
242                                                 forwarding_channel_manager.process_pending_htlc_forwards();
243                                         });
244                                 }
245                                 Event::SpendableOutputs { outputs } => {
246                                         let destination_address = bitcoind_client.get_new_address().await;
247                                         let output_descriptors = &outputs.iter().map(|a| a).collect::<Vec<_>>();
248                                         let tx_feerate =
249                                                 bitcoind_client.get_est_sat_per_1000_weight(ConfirmationTarget::Normal);
250                                         let spending_tx = keys_manager
251                                                 .spend_spendable_outputs(
252                                                         output_descriptors,
253                                                         Vec::new(),
254                                                         destination_address.script_pubkey(),
255                                                         tx_feerate,
256                                                         &Secp256k1::new(),
257                                                 )
258                                                 .unwrap();
259                                         bitcoind_client.broadcast_transaction(&spending_tx);
260                                 }
261                         }
262                 }
263                 tokio::time::sleep(Duration::from_secs(1)).await;
264         }
265 }
266
267 async fn start_ldk() {
268         let args = match cli::parse_startup_args() {
269                 Ok(user_args) => user_args,
270                 Err(()) => return,
271         };
272
273         // Initialize the LDK data directory if necessary.
274         let ldk_data_dir = format!("{}/.ldk", args.ldk_storage_dir_path);
275         fs::create_dir_all(ldk_data_dir.clone()).unwrap();
276
277         // Initialize our bitcoind client.
278         let bitcoind_client = match BitcoindClient::new(
279                 args.bitcoind_rpc_host.clone(),
280                 args.bitcoind_rpc_port,
281                 args.bitcoind_rpc_username.clone(),
282                 args.bitcoind_rpc_password.clone(),
283         )
284         .await
285         {
286                 Ok(client) => Arc::new(client),
287                 Err(e) => {
288                         println!("Failed to connect to bitcoind client: {}", e);
289                         return;
290                 }
291         };
292
293         // ## Setup
294         // Step 1: Initialize the FeeEstimator
295
296         // BitcoindClient implements the FeeEstimator trait, so it'll act as our fee estimator.
297         let fee_estimator = bitcoind_client.clone();
298
299         // Step 2: Initialize the Logger
300         let logger = Arc::new(FilesystemLogger::new(ldk_data_dir.clone()));
301
302         // Step 3: Initialize the BroadcasterInterface
303
304         // BitcoindClient implements the BroadcasterInterface trait, so it'll act as our transaction
305         // broadcaster.
306         let broadcaster = bitcoind_client.clone();
307
308         // Step 4: Initialize Persist
309         let persister = Arc::new(FilesystemPersister::new(ldk_data_dir.clone()));
310
311         // Step 5: Initialize the ChainMonitor
312         let chain_monitor: Arc<ChainMonitor> = Arc::new(chainmonitor::ChainMonitor::new(
313                 None,
314                 broadcaster.clone(),
315                 logger.clone(),
316                 fee_estimator.clone(),
317                 persister.clone(),
318         ));
319
320         // Step 6: Initialize the KeysManager
321
322         // The key seed that we use to derive the node privkey (that corresponds to the node pubkey) and
323         // other secret key material.
324         let keys_seed_path = format!("{}/keys_seed", ldk_data_dir.clone());
325         let keys_seed = if let Ok(seed) = fs::read(keys_seed_path.clone()) {
326                 assert_eq!(seed.len(), 32);
327                 let mut key = [0; 32];
328                 key.copy_from_slice(&seed);
329                 key
330         } else {
331                 let mut key = [0; 32];
332                 thread_rng().fill_bytes(&mut key);
333                 match File::create(keys_seed_path.clone()) {
334                         Ok(mut f) => {
335                                 f.write_all(&key).expect("Failed to write node keys seed to disk");
336                                 f.sync_all().expect("Failed to sync node keys seed to disk");
337                         }
338                         Err(e) => {
339                                 println!("ERROR: Unable to create keys seed file {}: {}", keys_seed_path, e);
340                                 return;
341                         }
342                 }
343                 key
344         };
345         let cur = SystemTime::now().duration_since(SystemTime::UNIX_EPOCH).unwrap();
346         let keys_manager = Arc::new(KeysManager::new(&keys_seed, cur.as_secs(), cur.subsec_nanos()));
347
348         // Step 7: Read ChannelMonitor state from disk
349         let mut channelmonitors = persister.read_channelmonitors(keys_manager.clone()).unwrap();
350
351         // Step 8: Initialize the ChannelManager
352         let user_config = UserConfig::default();
353         let mut restarting_node = true;
354         let (channel_manager_blockhash, mut channel_manager) = {
355                 if let Ok(mut f) = fs::File::open(format!("{}/manager", ldk_data_dir.clone())) {
356                         let mut channel_monitor_mut_references = Vec::new();
357                         for (_, channel_monitor) in channelmonitors.iter_mut() {
358                                 channel_monitor_mut_references.push(channel_monitor);
359                         }
360                         let read_args = ChannelManagerReadArgs::new(
361                                 keys_manager.clone(),
362                                 fee_estimator.clone(),
363                                 chain_monitor.clone(),
364                                 broadcaster.clone(),
365                                 logger.clone(),
366                                 user_config,
367                                 channel_monitor_mut_references,
368                         );
369                         <(BlockHash, ChannelManager)>::read(&mut f, read_args).unwrap()
370                 } else {
371                         // We're starting a fresh node.
372                         restarting_node = false;
373                         let getinfo_resp = bitcoind_client.get_blockchain_info().await;
374
375                         let chain_params = ChainParameters {
376                                 network: args.network,
377                                 best_block: BestBlock::new(
378                                         getinfo_resp.latest_blockhash,
379                                         getinfo_resp.latest_height as u32,
380                                 ),
381                         };
382                         let fresh_channel_manager = channelmanager::ChannelManager::new(
383                                 fee_estimator.clone(),
384                                 chain_monitor.clone(),
385                                 broadcaster.clone(),
386                                 logger.clone(),
387                                 keys_manager.clone(),
388                                 user_config,
389                                 chain_params,
390                         );
391                         (getinfo_resp.latest_blockhash, fresh_channel_manager)
392                 }
393         };
394
395         // Step 9: Sync ChannelMonitors and ChannelManager to chain tip
396         let mut chain_listener_channel_monitors = Vec::new();
397         let mut cache = UnboundedCache::new();
398         let mut chain_tip: Option<poll::ValidatedBlockHeader> = None;
399         if restarting_node {
400                 let mut chain_listeners =
401                         vec![(channel_manager_blockhash, &mut channel_manager as &mut dyn chain::Listen)];
402
403                 for (blockhash, channel_monitor) in channelmonitors.drain(..) {
404                         let outpoint = channel_monitor.get_funding_txo().0;
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 10: 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 11: Optional: Initialize the NetGraphMsgHandler
438         // XXX persist routing data
439         let genesis = genesis_block(args.network).header.block_hash();
440         let router = Arc::new(NetGraphMsgHandler::new(
441                 genesis,
442                 None::<Arc<dyn chain::Access + Send + Sync>>,
443                 logger.clone(),
444         ));
445
446         // Step 12: Initialize the PeerManager
447         let channel_manager: Arc<ChannelManager> = Arc::new(channel_manager);
448         let mut ephemeral_bytes = [0; 32];
449         rand::thread_rng().fill_bytes(&mut ephemeral_bytes);
450         let lightning_msg_handler =
451                 MessageHandler { chan_handler: channel_manager.clone(), route_handler: router.clone() };
452         let peer_manager: Arc<PeerManager> = Arc::new(PeerManager::new(
453                 lightning_msg_handler,
454                 keys_manager.get_node_secret(),
455                 &ephemeral_bytes,
456                 logger.clone(),
457         ));
458
459         // ## Running LDK
460         // Step 13: Initialize networking
461
462         // We poll for events in handle_ldk_events(..) rather than waiting for them over the
463         // mpsc::channel, so we can leave the event receiver as unused.
464         let (event_ntfn_sender, event_ntfn_receiver) = mpsc::channel(2);
465         let peer_manager_connection_handler = peer_manager.clone();
466         let event_notifier = event_ntfn_sender.clone();
467         let listening_port = args.ldk_peer_listening_port;
468         tokio::spawn(async move {
469                 let listener = std::net::TcpListener::bind(format!("0.0.0.0:{}", listening_port)).unwrap();
470                 loop {
471                         let peer_mgr = peer_manager_connection_handler.clone();
472                         let notifier = event_notifier.clone();
473                         let tcp_stream = listener.accept().unwrap().0;
474                         tokio::spawn(async move {
475                                 lightning_net_tokio::setup_inbound(peer_mgr.clone(), notifier.clone(), tcp_stream)
476                                         .await;
477                         });
478                 }
479         });
480
481         // Step 14: Connect and Disconnect Blocks
482         if chain_tip.is_none() {
483                 chain_tip =
484                         Some(init::validate_best_block_header(&mut bitcoind_client.deref()).await.unwrap());
485         }
486         let channel_manager_listener = channel_manager.clone();
487         let chain_monitor_listener = chain_monitor.clone();
488         let bitcoind_block_source = bitcoind_client.clone();
489         let network = args.network;
490         tokio::spawn(async move {
491                 let mut derefed = bitcoind_block_source.deref();
492                 let chain_poller = poll::ChainPoller::new(&mut derefed, network);
493                 let chain_listener = (chain_monitor_listener, channel_manager_listener);
494                 let mut spv_client =
495                         SpvClient::new(chain_tip.unwrap(), chain_poller, &mut cache, &chain_listener);
496                 loop {
497                         spv_client.poll_best_tip().await.unwrap();
498                         tokio::time::sleep(Duration::from_secs(1)).await;
499                 }
500         });
501
502         // Step 15: Initialize LDK Event Handling
503         let channel_manager_event_listener = channel_manager.clone();
504         let chain_monitor_event_listener = chain_monitor.clone();
505         let keys_manager_listener = keys_manager.clone();
506         // TODO: persist payment info to disk
507         let inbound_payments: PaymentInfoStorage = Arc::new(Mutex::new(HashMap::new()));
508         let outbound_payments: PaymentInfoStorage = Arc::new(Mutex::new(HashMap::new()));
509         let inbound_pmts_for_events = inbound_payments.clone();
510         let outbound_pmts_for_events = outbound_payments.clone();
511         let network = args.network;
512         let bitcoind_rpc = bitcoind_client.clone();
513         tokio::spawn(async move {
514                 handle_ldk_events(
515                         channel_manager_event_listener,
516                         chain_monitor_event_listener,
517                         bitcoind_rpc,
518                         keys_manager_listener,
519                         inbound_pmts_for_events,
520                         outbound_pmts_for_events,
521                         network,
522                         event_ntfn_receiver,
523                 )
524                 .await;
525         });
526
527         // Step 16 & 17: Persist ChannelManager & Background Processing
528         let data_dir = ldk_data_dir.clone();
529         let persist_channel_manager_callback =
530                 move |node: &ChannelManager| FilesystemPersister::persist_manager(data_dir.clone(), &*node);
531         BackgroundProcessor::start(
532                 persist_channel_manager_callback,
533                 channel_manager.clone(),
534                 peer_manager.clone(),
535                 logger.clone(),
536         );
537
538         // Reconnect to channel peers if possible.
539         let peer_data_path = format!("{}/channel_peer_data", ldk_data_dir.clone());
540         match disk::read_channel_peer_data(Path::new(&peer_data_path)) {
541                 Ok(mut info) => {
542                         for (pubkey, peer_addr) in info.drain() {
543                                 for chan_info in channel_manager.list_channels() {
544                                         if pubkey == chan_info.remote_network_id {
545                                                 let _ = cli::connect_peer_if_necessary(
546                                                         pubkey,
547                                                         peer_addr,
548                                                         peer_manager.clone(),
549                                                         event_ntfn_sender.clone(),
550                                                 );
551                                         }
552                                 }
553                         }
554                 }
555                 Err(e) => println!("ERROR: errored reading channel peer info from disk: {:?}", e),
556         }
557
558         // Start the CLI.
559         cli::poll_for_user_input(
560                 peer_manager.clone(),
561                 channel_manager.clone(),
562                 keys_manager.clone(),
563                 router.clone(),
564                 inbound_payments,
565                 outbound_payments,
566                 event_ntfn_sender,
567                 ldk_data_dir.clone(),
568                 logger.clone(),
569                 args.network,
570         )
571         .await;
572 }
573
574 #[tokio::main]
575 pub async fn main() {
576         start_ldk().await;
577 }