more consistent handling of peers_preferred during startup (#3578)

p2p/src/msg.rs

@@ -529,6 +529,40 @@ impl Readable for PeerAddrs {
 	}
 }
 
+impl IntoIterator for PeerAddrs {
+	type Item = PeerAddr;
+	type IntoIter = std::vec::IntoIter<Self::Item>;
+	fn into_iter(self) -> Self::IntoIter {
+		self.peers.into_iter()
+	}
+}
+
+impl Default for PeerAddrs {
+	fn default() -> Self {
+		PeerAddrs { peers: vec![] }
+	}
+}
+
+impl PeerAddrs {
+	pub fn as_slice(&self) -> &[PeerAddr] {
+		self.peers.as_slice()
+	}
+
+	pub fn contains(&self, addr: &PeerAddr) -> bool {
+		self.peers.contains(addr)
+	}
+
+	pub fn difference(&self, other: &[PeerAddr]) -> PeerAddrs {
+		let peers = self
+			.peers
+			.iter()
+			.filter(|x| !other.contains(x))
+			.cloned()
+			.collect();
+		PeerAddrs { peers }
+	}
+}
+
 /// We found some issue in the communication, sending an error back, usually
 /// followed by closing the connection.
 pub struct PeerError {

p2p/src/peers.rs

@@ -27,6 +27,7 @@ use crate::core::core::hash::{Hash, Hashed};
 use crate::core::core::{OutputIdentifier, Segment, SegmentIdentifier, TxKernel};
 use crate::core::global;
 use crate::core::pow::Difficulty;
+use crate::msg::PeerAddrs;
 use crate::peer::Peer;
 use crate::store::{PeerData, PeerStore, State};
 use crate::types::{
@@ -322,8 +323,10 @@ impl Peers {
 		&self,
 		max_inbound_count: usize,
 		max_outbound_count: usize,
-		preferred_peers: &[PeerAddr],
+		config: P2PConfig,
 	) {
+		let preferred_peers = config.peers_preferred.unwrap_or(PeerAddrs::default());
+
 		let mut rm = vec![];
 
 		// build a list of peers to be cleaned up

servers/src/grin/seed.rs

@@ -19,6 +19,7 @@
 
 use chrono::prelude::{DateTime, Utc};
 use chrono::{Duration, MIN_DATE};
+use p2p::{msg::PeerAddrs, P2PConfig};
 use rand::prelude::*;
 use std::collections::HashMap;
 use std::net::ToSocketAddrs;
@@ -51,11 +52,9 @@ const TESTNET_DNS_SEEDS: &[&str] = &[
 pub fn connect_and_monitor(
 	p2p_server: Arc<p2p::Server>,
 	seed_list: Box<dyn Fn() -> Vec<PeerAddr> + Send>,
-	preferred_peers: &[PeerAddr],
+	config: P2PConfig,
 	stop_state: Arc<StopState>,
 ) -> std::io::Result<thread::JoinHandle<()>> {
-	let preferred_peers = preferred_peers.to_vec();
-
 	thread::Builder::new()
 		.name("seed".to_string())
 		.spawn(move || {
@@ -66,12 +65,7 @@ pub fn connect_and_monitor(
 			let (tx, rx) = mpsc::channel();
 
 			// check seeds first
-			connect_to_seeds_and_preferred_peers(
+			connect_to_seeds_and_peers(peers.clone(), tx.clone(), seed_list, config);
-				peers.clone(),
-				tx.clone(),
-				seed_list,
-				&preferred_peers,
-			);
 
 			let mut prev = MIN_DATE.and_hms(0, 0, 0);
 			let mut prev_expire_check = MIN_DATE.and_hms(0, 0, 0);
@@ -109,12 +103,7 @@ pub fn connect_and_monitor(
 					);
 
 					// monitor additional peers if we need to add more
-					monitor_peers(
+					monitor_peers(peers.clone(), p2p_server.config.clone(), tx.clone());
-						peers.clone(),
-						p2p_server.config.clone(),
-						tx.clone(),
-						&preferred_peers,
-					);
 
 					prev = Utc::now();
 					start_attempt = cmp::min(6, start_attempt + 1);
@@ -137,12 +126,7 @@ pub fn connect_and_monitor(
 		})
 }
 
-fn monitor_peers(
+fn monitor_peers(peers: Arc<p2p::Peers>, config: p2p::P2PConfig, tx: mpsc::Sender<PeerAddr>) {
-	peers: Arc<p2p::Peers>,
-	config: p2p::P2PConfig,
-	tx: mpsc::Sender<PeerAddr>,
-	preferred_peers: &[PeerAddr],
-) {
 	// regularly check if we need to acquire more peers and if so, gets
 	// them from db
 	let mut total_count = 0;
@@ -195,7 +179,7 @@ fn monitor_peers(
 	peers.clean_peers(
 		config.peer_max_inbound_count() as usize,
 		config.peer_max_outbound_count() as usize,
-		preferred_peers,
+		config.clone(),
 	);
 
 	if peers.enough_outbound_peers() {
@@ -221,13 +205,14 @@ fn monitor_peers(
 	}
 
 	// Attempt to connect to any preferred peers.
-	for p in preferred_peers {
+	let peers_preferred = config.peers_preferred.unwrap_or(PeerAddrs::default());
+	for p in peers_preferred {
 		if !connected_peers.is_empty() {
-			if !connected_peers.contains(p) {
+			if !connected_peers.contains(&p) {
-				tx.send(*p).unwrap();
+				let _ = tx.send(p);
 			}
 		} else {
-			tx.send(*p).unwrap();
+			let _ = tx.send(p);
 		}
 	}
 
@@ -261,33 +246,50 @@ fn monitor_peers(
 
 // Check if we have any pre-existing peer in db. If so, start with those,
 // otherwise use the seeds provided.
-fn connect_to_seeds_and_preferred_peers(
+fn connect_to_seeds_and_peers(
 	peers: Arc<p2p::Peers>,
 	tx: mpsc::Sender<PeerAddr>,
 	seed_list: Box<dyn Fn() -> Vec<PeerAddr>>,
-	peers_preferred: &[PeerAddr],
+	config: P2PConfig,
 ) {
+	let peers_deny = config.peers_deny.unwrap_or(PeerAddrs::default());
+
+	// If "peers_allow" is explicitly configured then just use this list
+	// remembering to filter out "peers_deny".
+	if let Some(peers) = config.peers_allow {
+		for addr in peers.difference(peers_deny.as_slice()) {
+			let _ = tx.send(addr);
+		}
+		return;
+	}
+
+	// Always try our "peers_preferred" remembering to filter out "peers_deny".
+	if let Some(peers) = config.peers_preferred {
+		for addr in peers.difference(peers_deny.as_slice()) {
+			let _ = tx.send(addr);
+		}
+	}
+
 	// check if we have some peers in db
 	// look for peers that are able to give us other peers (via PEER_LIST capability)
 	let peers = peers.find_peers(p2p::State::Healthy, p2p::Capabilities::PEER_LIST, 100);
 
 	// if so, get their addresses, otherwise use our seeds
-	let mut peer_addrs = if peers.len() > 3 {
+	let peer_addrs = if peers.len() > 3 {
 		peers.iter().map(|p| p.addr).collect::<Vec<_>>()
 	} else {
 		seed_list()
 	};
 
-	// If we have preferred peers add them to the initial list
-	peer_addrs.extend_from_slice(peers_preferred);
-
 	if peer_addrs.is_empty() {
 		warn!("No seeds were retrieved.");
 	}
 
-	// connect to this first set of addresses
+	// connect to this initial set of peer addresses (either seeds or from our local db).
 	for addr in peer_addrs {
-		tx.send(addr).unwrap();
+		if !peers_deny.as_slice().contains(&addr) {
+			let _ = tx.send(addr);
+		}
 	}
 }
 

servers/src/grin/server.rs

@@ -240,7 +240,7 @@ impl Server {
 		let mut connect_thread = None;
 
 		if config.p2p_config.seeding_type != p2p::Seeding::Programmatic {
-			let seeder = match config.p2p_config.seeding_type {
+			let seed_list = match config.p2p_config.seeding_type {
 				p2p::Seeding::None => {
 					warn!("No seed configured, will stay solo until connected to");
 					seed::predefined_seeds(vec![])
@@ -257,15 +257,10 @@ impl Server {
 				_ => unreachable!(),
 			};
 
-			let preferred_peers = match &config.p2p_config.peers_preferred {
-				Some(addrs) => addrs.peers.clone(),
-				None => vec![],
-			};
-
 			connect_thread = Some(seed::connect_and_monitor(
 				p2p_server.clone(),
-				seeder,
+				seed_list,
-				&preferred_peers,
+				config.p2p_config.clone(),
 				stop_state.clone(),
 			)?);
 		}