_ Git - rapid-gossip-sync-server/blob - src/lib.rs

   1 #![deny(unsafe_code)]
   2 #![deny(broken_intra_doc_links)]
   3 #![deny(private_intra_doc_links)]
   4 #![deny(non_upper_case_globals)]
   5 #![deny(non_camel_case_types)]
   6 #![deny(non_snake_case)]
   7 #![deny(unused_variables)]
   8 #![deny(unused_imports)]
   9
  10 extern crate core;
  11
  12 use std::collections::{HashMap, HashSet};
  13 use std::fs::File;
  14 use std::io::BufReader;
  15 use std::sync::Arc;
  16
  17 use lightning::routing::gossip::{NetworkGraph, NodeId};
  18 use lightning::util::logger::Logger;
  19 use lightning::util::ser::{ReadableArgs, Writeable};
  20 use tokio::sync::mpsc;
  21 use crate::lookup::DeltaSet;
  22
  23 use crate::persistence::GossipPersister;
  24 use crate::serialization::UpdateSerialization;
  25 use crate::snapshot::Snapshotter;
  26 use crate::types::RGSSLogger;
  27
  28 mod downloader;
  29 mod tracking;
  30 mod lookup;
  31 mod persistence;
  32 mod serialization;
  33 mod snapshot;
  34 mod config;
  35 mod hex_utils;
  36 mod verifier;
  37
  38 pub mod types;
  39
  40 /// The purpose of this prefix is to identify the serialization format, should other rapid gossip
  41 /// sync formats arise in the future.
  42 ///
  43 /// The fourth byte is the protocol version in case our format gets updated.
  44 const GOSSIP_PREFIX: [u8; 4] = [76, 68, 75, 1];
  45
  46 pub struct RapidSyncProcessor<L: Logger> {
  47         network_graph: Arc<NetworkGraph<Arc<L>>>,
  48         logger: Arc<L>
  49 }
  50
  51 pub struct SerializedResponse {
  52         pub data: Vec<u8>,
  53         pub message_count: u32,
  54         pub announcement_count: u32,
  55         pub update_count: u32,
  56         pub update_count_full: u32,
  57         pub update_count_incremental: u32,
  58 }
  59
  60 impl<L: Logger + Send + Sync + 'static> RapidSyncProcessor<L> {
  61         pub fn new(logger: Arc<L>) -> Self {
  62                 let network = config::network();
  63                 let network_graph = if let Ok(file) = File::open(&config::network_graph_cache_path()) {
  64                         println!("Initializing from cached network graph…");
  65                         let mut buffered_reader = BufReader::new(file);
  66                         let network_graph_result = NetworkGraph::read(&mut buffered_reader, logger.clone());
  67                         if let Ok(network_graph) = network_graph_result {
  68                                 println!("Initialized from cached network graph!");
  69                                 network_graph
  70                         } else {
  71                                 println!("Initialization from cached network graph failed: {}", network_graph_result.err().unwrap());
  72                                 NetworkGraph::new(network, logger.clone())
  73                         }
  74                 } else {
  75                         NetworkGraph::new(network, logger.clone())
  76                 };
  77                 let arc_network_graph = Arc::new(network_graph);
  78                 Self {
  79                         network_graph: arc_network_graph,
  80                         logger
  81                 }
  82         }
  83
  84         pub async fn start_sync(&self) {
  85                 // means to indicate sync completion status within this module
  86                 let (sync_completion_sender, mut sync_completion_receiver) = mpsc::channel::<()>(1);
  87
  88                 if config::DOWNLOAD_NEW_GOSSIP {
  89                         let (mut persister, persistence_sender) = GossipPersister::new(Arc::clone(&self.network_graph));
  90
  91                         println!("Starting gossip download");
  92                         tokio::spawn(tracking::download_gossip(persistence_sender, sync_completion_sender,
  93                                 Arc::clone(&self.network_graph), Arc::clone(&self.logger)));
  94                         println!("Starting gossip db persistence listener");
  95                         tokio::spawn(async move { persister.persist_gossip().await; });
  96                 } else {
  97                         sync_completion_sender.send(()).await.unwrap();
  98                 }
  99
 100                 let sync_completion = sync_completion_receiver.recv().await;
 101                 if sync_completion.is_none() {
 102                         panic!("Sync failed!");
 103                 }
 104                 println!("Initial sync complete!");
 105
 106                 // start the gossip snapshotting service
 107                 Snapshotter::new(Arc::clone(&self.network_graph)).snapshot_gossip().await;
 108         }
 109 }
 110
 111 /// This method generates a no-op blob that can be used as a delta where none exists.
 112 ///
 113 /// The primary purpose of this method is the scenario of a client retrieving and processing a
 114 /// given snapshot, and then immediately retrieving the would-be next snapshot at the timestamp
 115 /// indicated by the one that was just processed.
 116 /// Previously, there would not be a new snapshot to be processed for that particular timestamp yet,
 117 /// and the server would return a 404 error.
 118 ///
 119 /// In principle, this method could also be used to address another unfortunately all too common
 120 /// pitfall: requesting snapshots from intermediate timestamps, i. e. those that are not multiples
 121 /// of our granularity constant. Note that for that purpose, this method could be very dangerous,
 122 /// because if consumed, the `timestamp` value calculated here will overwrite the timestamp that
 123 /// the client previously had, which could result in duplicated or omitted gossip down the line.
 124 fn serialize_empty_blob(current_timestamp: u64) -> Vec<u8> {
 125         let mut blob = GOSSIP_PREFIX.to_vec();
 126
 127         let network = config::network();
 128         let genesis_block = bitcoin::blockdata::constants::genesis_block(network);
 129         let chain_hash = genesis_block.block_hash();
 130         chain_hash.write(&mut blob).unwrap();
 131
 132         let blob_timestamp = Snapshotter::<RGSSLogger>::round_down_to_nearest_multiple(current_timestamp, config::SNAPSHOT_CALCULATION_INTERVAL as u64) as u32;
 133         blob_timestamp.write(&mut blob).unwrap();
 134
 135         0u32.write(&mut blob).unwrap(); // node count
 136         0u32.write(&mut blob).unwrap(); // announcement count
 137         0u32.write(&mut blob).unwrap(); // update count
 138
 139         blob
 140 }
 141
 142 async fn serialize_delta<L: Logger>(network_graph: Arc<NetworkGraph<Arc<L>>>, last_sync_timestamp: u32) -> SerializedResponse {
 143         let (client, connection) = lookup::connect_to_db().await;
 144
 145         network_graph.remove_stale_channels_and_tracking();
 146
 147         tokio::spawn(async move {
 148                 if let Err(e) = connection.await {
 149                         panic!("connection error: {}", e);
 150                 }
 151         });
 152
 153         let mut output: Vec<u8> = vec![];
 154
 155         // set a flag if the chain hash is prepended
 156         // chain hash only necessary if either channel announcements or non-incremental updates are present
 157         // for announcement-free incremental-only updates, chain hash can be skipped
 158
 159         let mut node_id_set: HashSet<NodeId> = HashSet::new();
 160         let mut node_id_indices: HashMap<NodeId, usize> = HashMap::new();
 161         let mut node_ids: Vec<NodeId> = Vec::new();
 162         let mut duplicate_node_ids: i32 = 0;
 163
 164         let mut get_node_id_index = |node_id: NodeId| {
 165                 if node_id_set.insert(node_id) {
 166                         node_ids.push(node_id);
 167                         let index = node_ids.len() - 1;
 168                         node_id_indices.insert(node_id, index);
 169                         return index;
 170                 }
 171                 duplicate_node_ids += 1;
 172                 node_id_indices[&node_id]
 173         };
 174
 175         let mut delta_set = DeltaSet::new();
 176         lookup::fetch_channel_announcements(&mut delta_set, network_graph, &client, last_sync_timestamp).await;
 177         println!("announcement channel count: {}", delta_set.len());
 178         lookup::fetch_channel_updates(&mut delta_set, &client, last_sync_timestamp).await;
 179         println!("update-fetched channel count: {}", delta_set.len());
 180         lookup::filter_delta_set(&mut delta_set);
 181         println!("update-filtered channel count: {}", delta_set.len());
 182         let serialization_details = serialization::serialize_delta_set(delta_set, last_sync_timestamp);
 183
 184         // process announcements
 185         // write the number of channel announcements to the output
 186         let announcement_count = serialization_details.announcements.len() as u32;
 187         announcement_count.write(&mut output).unwrap();
 188         let mut previous_announcement_scid = 0;
 189         for current_announcement in serialization_details.announcements {
 190                 let id_index_1 = get_node_id_index(current_announcement.node_id_1);
 191                 let id_index_2 = get_node_id_index(current_announcement.node_id_2);
 192                 let mut stripped_announcement = serialization::serialize_stripped_channel_announcement(&current_announcement, id_index_1, id_index_2, previous_announcement_scid);
 193                 output.append(&mut stripped_announcement);
 194
 195                 previous_announcement_scid = current_announcement.short_channel_id;
 196         }
 197
 198         // process updates
 199         let mut previous_update_scid = 0;
 200         let update_count = serialization_details.updates.len() as u32;
 201         update_count.write(&mut output).unwrap();
 202
 203         let default_update_values = serialization_details.full_update_defaults;
 204         if update_count > 0 {
 205                 default_update_values.cltv_expiry_delta.write(&mut output).unwrap();
 206                 default_update_values.htlc_minimum_msat.write(&mut output).unwrap();
 207                 default_update_values.fee_base_msat.write(&mut output).unwrap();
 208                 default_update_values.fee_proportional_millionths.write(&mut output).unwrap();
 209                 default_update_values.htlc_maximum_msat.write(&mut output).unwrap();
 210         }
 211
 212         let mut update_count_full = 0;
 213         let mut update_count_incremental = 0;
 214         for current_update in serialization_details.updates {
 215                 match &current_update {
 216                         UpdateSerialization::Full(_) => {
 217                                 update_count_full += 1;
 218                         }
 219                         UpdateSerialization::Incremental(_, _) | UpdateSerialization::Reminder(_, _) => {
 220                                 update_count_incremental += 1;
 221                         }
 222                 };
 223
 224                 let mut stripped_update = serialization::serialize_stripped_channel_update(&current_update, &default_update_values, previous_update_scid);
 225                 output.append(&mut stripped_update);
 226
 227                 previous_update_scid = current_update.scid();
 228         }
 229
 230         // some stats
 231         let message_count = announcement_count + update_count;
 232
 233         let mut prefixed_output = GOSSIP_PREFIX.to_vec();
 234
 235         // always write the chain hash
 236         serialization_details.chain_hash.write(&mut prefixed_output).unwrap();
 237         // always write the latest seen timestamp
 238         let latest_seen_timestamp = serialization_details.latest_seen;
 239         let overflow_seconds = latest_seen_timestamp % config::SNAPSHOT_CALCULATION_INTERVAL;
 240         let serialized_seen_timestamp = latest_seen_timestamp.saturating_sub(overflow_seconds);
 241         serialized_seen_timestamp.write(&mut prefixed_output).unwrap();
 242
 243         let node_id_count = node_ids.len() as u32;
 244         node_id_count.write(&mut prefixed_output).unwrap();
 245
 246         for current_node_id in node_ids {
 247                 current_node_id.write(&mut prefixed_output).unwrap();
 248         }
 249
 250         prefixed_output.append(&mut output);
 251
 252         println!("duplicated node ids: {}", duplicate_node_ids);
 253         println!("latest seen timestamp: {:?}", serialization_details.latest_seen);
 254
 255         SerializedResponse {
 256                 data: prefixed_output,
 257                 message_count,
 258                 announcement_count,
 259                 update_count,
 260                 update_count_full,
 261                 update_count_incremental,
 262         }
 263 }