lightning: Handle your_peer_storage from our peers.

Author: Aditya Sharma

lightning/src/ln/channelmanager.rs

@@ -51,6 +51,7 @@ use crate::ln::features::Bolt11InvoiceFeatures;
 use crate::routing::router::{BlindedTail, InFlightHtlcs, Path, Payee, PaymentParameters, Route, RouteParameters, Router};
 use crate::ln::onion_payment::{check_incoming_htlc_cltv, create_recv_pending_htlc_info, create_fwd_pending_htlc_info, decode_incoming_update_add_htlc_onion, InboundHTLCErr, NextPacketDetails};
 use crate::ln::msgs;
+use crate::ln::chan_utils::CounterpartyCommitmentSecrets;
 use crate::ln::onion_utils;
 use crate::ln::onion_utils::{HTLCFailReason, INVALID_ONION_BLINDING};
 use crate::ln::msgs::{ChannelMessageHandler, DecodeError, LightningError};
@@ -2601,6 +2602,14 @@ where
 		&self.default_configuration
 	}
 
+	pub fn get_encrypted_our_peer_storage(&self) -> Vec<u8> {
+		let mut peer_storage = VecWriter(Vec::new());
+		self.our_peer_storage.read().unwrap().write(&mut peer_storage).unwrap();
+		let mut encrypted_blob = vec![0;peer_storage.0.len() + 16];
+		self.inbound_payment_key.encrypt_our_peer_storage(&mut encrypted_blob, 0u64, b"", &peer_storage.0[..]);
+		encrypted_blob
+	}
+
 	fn create_and_insert_outbound_scid_alias(&self) -> u64 {
 		let height = self.best_block.read().unwrap().height;
 		let mut outbound_scid_alias = 0;
@@ -6797,6 +6806,73 @@ where
 		handle_new_monitor_update!(self, min_funded_chan.context.get_funding_txo().unwrap(), peer_storage_update, peer_state_lock, peer_state, per_peer_state, min_funded_chan);
 	}
 
+	fn internal_your_peer_storage(&self, counterparty_node_id: &PublicKey, msg: &msgs::YourPeerStorageMessage) {
+		let per_peer_state = self.per_peer_state.read().unwrap();
+		let peer_state_mutex = match per_peer_state.get(counterparty_node_id) {
+			Some(peer_state_mutex) => peer_state_mutex,
+			None => return,
+		};
+		let mut peer_state_lock = peer_state_mutex.lock().unwrap();
+		let peer_state = &mut *peer_state_lock;
+		let warn_msg = events::MessageSendEvent::HandleError {
+			node_id: *counterparty_node_id,
+			action: msgs::ErrorAction::SendWarningMessage {
+				msg: msgs::WarningMessage {
+					channel_id: ChannelId::from_bytes([0; 32]),
+					data: "Invalid peer storage sent!".to_owned(),
+				},
+				log_level: Level::Trace,
+			}
+		};
+
+		if msg.data.len() < 16 {
+			peer_state.pending_msg_events.push(warn_msg);
+			return;
+		}
+ 		let mut res = vec![0; msg.data.len() - 16];
+
+		match self.inbound_payment_key.decrypt_our_peer_storage(&mut res, 0u64, b"", msg.data.as_slice()) {
+			Ok(()) => {
+				// Decryption successful, the plaintext is now stored in `res`
+				println!("Decryption successful: {:?}", res);
+				let our_peer_storage = <OurPeerStorage as Readable>::read(&mut ::std::io::Cursor::new(res)).unwrap();
+				let stored_channels = self.list_channels();
+
+				for ps_channel in &our_peer_storage.channels {
+					if let Some(_channel) = stored_channels.iter().find(|chan| chan.channel_id == ps_channel.channel_id) {
+						continue;
+					} else {						
+						let keys = self.signer_provider.derive_channel_signer(ps_channel.channel_value_stoshis, ps_channel.channel_keys_id);
+						let monitor = ChannelMonitor::new_stub(self.secp_ctx.clone(), ps_channel, *self.best_block.read().unwrap(), keys);
+						let monitor_res =  self.chain_monitor.watch_channel(ps_channel.funding_outpoint, monitor);
+						if let Ok(_persist_state) = monitor_res {
+							let force_close_update = ChannelMonitorUpdate {
+								update_id: CLOSED_CHANNEL_UPDATE_ID,
+								counterparty_node_id: Some(ps_channel.counterparty_node_id),
+								updates: vec![ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast: false }],
+								channel_id: Some(ps_channel.channel_id),
+							};
+							let update_res = self.chain_monitor.update_channel(ps_channel.funding_outpoint, &force_close_update);
+							if update_res != ChannelMonitorUpdateStatus::Completed {
+								log_error!(WithContext::from(&self.logger, None, Some(ps_channel.channel_id)),
+									"Critical error: failed to update channel monitor from peer storage to force close.",);
+							}
+						}
+						else {
+							unreachable!("We already checked this outpoint was not recognised by the node.");
+						}
+					}
+				}
+			}
+			Err(_) => {
+				// Decryption failed
+				peer_state.pending_msg_events.push(warn_msg);
+				return;
+			}
+		}
+		
+	}
+
 	fn internal_funding_signed(&self, counterparty_node_id: &PublicKey, msg: &msgs::FundingSigned) -> Result<(), MsgHandleErrInternal> {
 		let best_block = *self.best_block.read().unwrap();
 		let per_peer_state = self.per_peer_state.read().unwrap();
@@ -9186,7 +9262,10 @@ where
 	}
 
 	fn handle_your_peer_storage(&self, counterparty_node_id: &PublicKey, msg: &msgs::YourPeerStorageMessage) {
-		//TODO
+		let _persistence_guard = PersistenceNotifierGuard::optionally_notify(self, || {
+			self.internal_your_peer_storage(counterparty_node_id, msg);
+			NotifyOption::SkipPersistHandleEvents
+		});
 	}
 
 	fn handle_channel_ready(&self, counterparty_node_id: &PublicKey, msg: &msgs::ChannelReady) {
@@ -9573,13 +9652,23 @@ where
 				}
 
 				let peer_storage = peer_state.peer_storage.clone();
-
-				pending_msg_events.push(events::MessageSendEvent::SendYourPeerStorageMessage { 
-					node_id: counterparty_node_id.clone(),
-					msg: msgs::YourPeerStorageMessage {
-						data: peer_storage
-					},
-				});
+				if peer_storage.len() > 0 {
+					pending_msg_events.push(events::MessageSendEvent::SendYourPeerStorageMessage { 
+						node_id: counterparty_node_id.clone(),
+						msg: msgs::YourPeerStorageMessage {
+							data: peer_storage
+						},
+					});
+				}
+				if peer_state.latest_features.supports_provide_peer_storage() {
+					let our_peer_storage = self.get_encrypted_our_peer_storage();
+					pending_msg_events.push(events::MessageSendEvent::SendPeerStorageMessage { 
+						node_id: counterparty_node_id.clone(),
+						msg: msgs::PeerStorageMessage {
+							data: our_peer_storage
+						},
+					});
+				}
 			}
 
 			return NotifyOption::SkipPersistHandleEvents;