Reserved peers CLI flag (#528)

substrate/substrate/cli/src/cli.yml

@@ -70,6 +70,12 @@ args:
       help: Specify a list of bootnodes
       takes_value: true
       multiple: true
+  - reserved-nodes:
+      long: reserved-nodes
+      value_name: URL
+      help: Specify a list of reserved node addresses
+      takes_value: true
+      multiple: true
   - chain:
       long: chain
       value_name: CHAIN_SPEC

substrate/substrate/cli/src/lib.rs

@@ -61,6 +61,7 @@ use service::{
 	ServiceFactory, FactoryFullConfiguration, RuntimeGenesis,
 	FactoryGenesis, PruningMode, ChainSpec,
 };
+use network::NonReservedPeerMode;
 
 use std::io::{Write, Read, stdin, stdout};
 use std::iter;
@@ -278,6 +279,12 @@ where
 			.map_or(Default::default(), |v| v.map(|n| n.to_owned()).collect::<Vec<_>>()));
 		config.network.config_path = Some(network_path(&base_path, config.chain_spec.id()).to_string_lossy().into());
 		config.network.net_config_path = config.network.config_path.clone();
+		config.network.reserved_nodes.extend(matches
+			 .values_of("reserved-nodes")
+			 .map_or(Default::default(), |v| v.map(|n| n.to_owned()).collect::<Vec<_>>()));
+		if !config.network.reserved_nodes.is_empty() {
+			config.network.non_reserved_mode = NonReservedPeerMode::Deny;
+		}
 
 		let port = match matches.value_of("port") {
 			Some(port) => port.parse().map_err(|_| "Invalid p2p port value specified.")?,

substrate/substrate/network-libp2p/src/service.rs

@@ -506,6 +506,16 @@ fn init_thread(
 		}
 	}
 
+	shared.network_state.set_non_reserved_mode(shared.config.non_reserved_mode.clone());
+	for reserved in shared.config.reserved_nodes.iter() {
+		match shared.network_state.add_reserved_peer(reserved) {
+			Ok(who) => {
+				trace!(target: "sub-libp2p", "Added reseved peer {:?}", who);
+			},
+			Err(err) => warn!(target:"sub-libp2p", "Couldn't parse reserved address: {}", err),
+		}
+	}
+
 	// Start connecting to nodes now.
 	connect_to_nodes(shared.clone(), transport.clone(), &swarm_controller);