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