_ 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::ops::Deref;
  16 use std::sync::Arc;
  17
  18 use lightning::routing::gossip::{NetworkGraph, NodeId};
  19 use lightning::util::logger::Logger;
  20 use lightning::util::ser::{ReadableArgs, Writeable};
  21 use tokio::sync::mpsc;
  22 use crate::lookup::DeltaSet;
  23
  24 use crate::persistence::GossipPersister;
  25 use crate::serialization::UpdateSerialization;
  26 use crate::snapshot::Snapshotter;
  27 use crate::types::RGSSLogger;
  28
  29 mod downloader;
  30 mod tracking;
  31 mod lookup;
  32 mod persistence;
  33 mod serialization;
  34 mod snapshot;
  35 mod config;
  36 mod hex_utils;
  37 mod verifier;
  38
  39 pub mod types;
  40
  41 /// The purpose of this prefix is to identify the serialization format, should other rapid gossip
  42 /// sync formats arise in the future.
  43 ///
  44 /// The fourth byte is the protocol version in case our format gets updated.
  45 const GOSSIP_PREFIX: [u8; 4] = [76, 68, 75, 1];
  46
  47 pub struct RapidSyncProcessor<L: Deref> where L::Target: Logger {
  48         network_graph: Arc<NetworkGraph<L>>,
  49         logger: L
  50 }
  51
  52 pub struct SerializedResponse {
  53         pub data: Vec<u8>,
  54         pub message_count: u32,
  55         pub announcement_count: u32,
  56         pub update_count: u32,
  57         pub update_count_full: u32,
  58         pub update_count_incremental: u32,
  59 }
  60
  61 impl<L: Deref + Clone + Send + Sync + 'static> RapidSyncProcessor<L> where L::Target: Logger {
  62         pub fn new(logger: L) -> Self {
  63                 let network = config::network();
  64                 let network_graph = if let Ok(file) = File::open(&config::network_graph_cache_path()) {
  65                         println!("Initializing from cached network graph…");
  66                         let mut buffered_reader = BufReader::new(file);
  67                         let network_graph_result = NetworkGraph::read(&mut buffered_reader, logger.clone());
  68                         if let Ok(network_graph) = network_graph_result {
  69                                 println!("Initialized from cached network graph!");
  70                                 network_graph
  71                         } else {
  72                                 println!("Initialization from cached network graph failed: {}", network_graph_result.err().unwrap());
  73                                 NetworkGraph::new(network, logger.clone())
  74                         }
  75                 } else {
  76                         NetworkGraph::new(network, logger.clone())
  77                 };
  78                 let arc_network_graph = Arc::new(network_graph);
  79                 Self {
  80                         network_graph: arc_network_graph,
  81                         logger
  82                 }
  83         }
  84
  85         pub async fn start_sync(&self) {
  86                 // means to indicate sync completion status within this module
  87                 let (sync_completion_sender, mut sync_completion_receiver) = mpsc::channel::<()>(1);
  88
  89                 if config::DOWNLOAD_NEW_GOSSIP {
  90                         let (mut persister, persistence_sender) = GossipPersister::new(Arc::clone(&self.network_graph));
  91
  92                         println!("Starting gossip download");
  93                         tokio::spawn(tracking::download_gossip(persistence_sender, sync_completion_sender,
  94                                 Arc::clone(&self.network_graph), self.logger.clone()));
  95                         println!("Starting gossip db persistence listener");
  96                         tokio::spawn(async move { persister.persist_gossip().await; });
  97                 } else {
  98                         sync_completion_sender.send(()).await.unwrap();
  99                 }
 100
 101                 let sync_completion = sync_completion_receiver.recv().await;
 102                 if sync_completion.is_none() {
 103                         panic!("Sync failed!");
 104                 }
 105                 println!("Initial sync complete!");
 106
 107                 // start the gossip snapshotting service
 108                 Snapshotter::new(Arc::clone(&self.network_graph)).snapshot_gossip().await;
 109         }
 110 }
 111
 112 /// This method generates a no-op blob that can be used as a delta where none exists.
 113 ///
 114 /// The primary purpose of this method is the scenario of a client retrieving and processing a
 115 /// given snapshot, and then immediately retrieving the would-be next snapshot at the timestamp
 116 /// indicated by the one that was just processed.
 117 /// Previously, there would not be a new snapshot to be processed for that particular timestamp yet,
 118 /// and the server would return a 404 error.
 119 ///
 120 /// In principle, this method could also be used to address another unfortunately all too common
 121 /// pitfall: requesting snapshots from intermediate timestamps, i. e. those that are not multiples
 122 /// of our granularity constant. Note that for that purpose, this method could be very dangerous,
 123 /// because if consumed, the `timestamp` value calculated here will overwrite the timestamp that
 124 /// the client previously had, which could result in duplicated or omitted gossip down the line.
 125 fn serialize_empty_blob(current_timestamp: u64) -> Vec<u8> {
 126         let mut blob = GOSSIP_PREFIX.to_vec();
 127
 128         let network = config::network();
 129         let genesis_block = bitcoin::blockdata::constants::genesis_block(network);
 130         let chain_hash = genesis_block.block_hash();
 131         chain_hash.write(&mut blob).unwrap();
 132
 133         let blob_timestamp = Snapshotter::<Arc<RGSSLogger>>::round_down_to_nearest_multiple(current_timestamp, config::SNAPSHOT_CALCULATION_INTERVAL as u64) as u32;
 134         blob_timestamp.write(&mut blob).unwrap();
 135
 136         0u32.write(&mut blob).unwrap(); // node count
 137         0u32.write(&mut blob).unwrap(); // announcement count
 138         0u32.write(&mut blob).unwrap(); // update count
 139
 140         blob
 141 }
 142
 143 async fn serialize_delta<L: Deref>(network_graph: Arc<NetworkGraph<L>>, last_sync_timestamp: u32) -> SerializedResponse where L::Target: Logger {
 144         let (client, connection) = lookup::connect_to_db().await;
 145
 146         network_graph.remove_stale_channels_and_tracking();
 147
 148         tokio::spawn(async move {
 149                 if let Err(e) = connection.await {
 150                         panic!("connection error: {}", e);
 151                 }
 152         });
 153
 154         let mut output: Vec<u8> = vec![];
 155
 156         // set a flag if the chain hash is prepended
 157         // chain hash only necessary if either channel announcements or non-incremental updates are present
 158         // for announcement-free incremental-only updates, chain hash can be skipped
 159
 160         let mut node_id_set: HashSet<NodeId> = HashSet::new();
 161         let mut node_id_indices: HashMap<NodeId, usize> = HashMap::new();
 162         let mut node_ids: Vec<NodeId> = Vec::new();
 163         let mut duplicate_node_ids: i32 = 0;
 164
 165         let mut get_node_id_index = |node_id: NodeId| {
 166                 if node_id_set.insert(node_id) {
 167                         node_ids.push(node_id);
 168                         let index = node_ids.len() - 1;
 169                         node_id_indices.insert(node_id, index);
 170                         return index;
 171                 }
 172                 duplicate_node_ids += 1;
 173                 node_id_indices[&node_id]
 174         };
 175
 176         let mut delta_set = DeltaSet::new();
 177         lookup::fetch_channel_announcements(&mut delta_set, network_graph, &client, last_sync_timestamp).await;
 178         println!("announcement channel count: {}", delta_set.len());
 179         lookup::fetch_channel_updates(&mut delta_set, &client, last_sync_timestamp).await;
 180         println!("update-fetched channel count: {}", delta_set.len());
 181         lookup::filter_delta_set(&mut delta_set);
 182         println!("update-filtered channel count: {}", delta_set.len());
 183         let serialization_details = serialization::serialize_delta_set(delta_set, last_sync_timestamp);
 184
 185         // process announcements
 186         // write the number of channel announcements to the output
 187         let announcement_count = serialization_details.announcements.len() as u32;
 188         announcement_count.write(&mut output).unwrap();
 189         let mut previous_announcement_scid = 0;
 190         for current_announcement in serialization_details.announcements {
 191                 let id_index_1 = get_node_id_index(current_announcement.node_id_1);
 192                 let id_index_2 = get_node_id_index(current_announcement.node_id_2);
 193                 let mut stripped_announcement = serialization::serialize_stripped_channel_announcement(&current_announcement, id_index_1, id_index_2, previous_announcement_scid);
 194                 output.append(&mut stripped_announcement);
 195
 196                 previous_announcement_scid = current_announcement.short_channel_id;
 197         }
 198
 199         // process updates
 200         let mut previous_update_scid = 0;
 201         let update_count = serialization_details.updates.len() as u32;
 202         update_count.write(&mut output).unwrap();
 203
 204         let default_update_values = serialization_details.full_update_defaults;
 205         if update_count > 0 {
 206                 default_update_values.cltv_expiry_delta.write(&mut output).unwrap();
 207                 default_update_values.htlc_minimum_msat.write(&mut output).unwrap();
 208                 default_update_values.fee_base_msat.write(&mut output).unwrap();
 209                 default_update_values.fee_proportional_millionths.write(&mut output).unwrap();
 210                 default_update_values.htlc_maximum_msat.write(&mut output).unwrap();
 211         }
 212
 213         let mut update_count_full = 0;
 214         let mut update_count_incremental = 0;
 215         for current_update in serialization_details.updates {
 216                 match &current_update {
 217                         UpdateSerialization::Full(_) => {
 218                                 update_count_full += 1;
 219                         }
 220                         UpdateSerialization::Incremental(_, _) | UpdateSerialization::Reminder(_, _) => {
 221                                 update_count_incremental += 1;
 222                         }
 223                 };
 224
 225                 let mut stripped_update = serialization::serialize_stripped_channel_update(&current_update, &default_update_values, previous_update_scid);
 226                 output.append(&mut stripped_update);
 227
 228                 previous_update_scid = current_update.scid();
 229         }
 230
 231         // some stats
 232         let message_count = announcement_count + update_count;
 233
 234         let mut prefixed_output = GOSSIP_PREFIX.to_vec();
 235
 236         // always write the chain hash
 237         serialization_details.chain_hash.write(&mut prefixed_output).unwrap();
 238         // always write the latest seen timestamp
 239         let latest_seen_timestamp = serialization_details.latest_seen;
 240         let overflow_seconds = latest_seen_timestamp % config::SNAPSHOT_CALCULATION_INTERVAL;
 241         let serialized_seen_timestamp = latest_seen_timestamp.saturating_sub(overflow_seconds);
 242         serialized_seen_timestamp.write(&mut prefixed_output).unwrap();
 243
 244         let node_id_count = node_ids.len() as u32;
 245         node_id_count.write(&mut prefixed_output).unwrap();
 246
 247         for current_node_id in node_ids {
 248                 current_node_id.write(&mut prefixed_output).unwrap();
 249         }
 250
 251         prefixed_output.append(&mut output);
 252
 253         println!("duplicated node ids: {}", duplicate_node_ids);
 254         println!("latest seen timestamp: {:?}", serialization_details.latest_seen);
 255
 256         SerializedResponse {
 257                 data: prefixed_output,
 258                 message_count,
 259                 announcement_count,
 260                 update_count,
 261                 update_count_full,
 262                 update_count_incremental,
 263         }
 264 }