Set reserved nodes with offchain worker. (#6996)

* add offchain worker api to set reserved nodes.

* new offchain api to get node public key.

* node public key from converter

* refactor set reserved nodes ocw api.

* new ndoe authorization pallet

* remove unnecessary clone and more.

* more

* tests for node authorization pallet

* remove dependency

* fix build

* more tests.

* refactor

* Update primitives/core/src/offchain/testing.rs

Co-authored-by: Tomasz Drwięga <tomusdrw@users.noreply.github.com>

* Update frame/node-authorization/src/lib.rs

Co-authored-by: Tomasz Drwięga <tomusdrw@users.noreply.github.com>

* Update frame/node-authorization/src/lib.rs

Co-authored-by: Tomasz Drwięga <tomusdrw@users.noreply.github.com>

* Update frame/node-authorization/src/lib.rs

Co-authored-by: Tomasz Drwięga <tomusdrw@users.noreply.github.com>

* format code

* expose NetworkService

* remove NetworkStateInfo in offchain

* replace NodePublicKey with PeerId.

* set max length of peer id.

* clear more

* use BTreeSet for set of peers.

* decode opaque peer id.

* extract NetworkProvider for client offchain.

* use OpaquePeerId in node authorization pallet.

* fix test

* better documentation

* fix test

* doc

* more fix

* Update primitives/core/src/offchain/mod.rs

Co-authored-by: Pierre Krieger <pierre.krieger1708@gmail.com>

* Update client/offchain/src/api.rs

Co-authored-by: Pierre Krieger <pierre.krieger1708@gmail.com>

* derive serialize and deserialize

Co-authored-by: Tomasz Drwięga <tomusdrw@users.noreply.github.com>
Co-authored-by: Pierre Krieger <pierre.krieger1708@gmail.com>

substrate/Cargo.lock

@@ -4738,6 +4738,20 @@ dependencies = [
  "sp-std",
 ]
 
+[[package]]
+name = "pallet-node-authorization"
+version = "2.0.0-rc6"
+dependencies = [
+ "frame-support",
+ "frame-system",
+ "parity-scale-codec",
+ "serde",
+ "sp-core",
+ "sp-io",
+ "sp-runtime",
+ "sp-std",
+]
+
 [[package]]
 name = "pallet-offences"
 version = "2.0.0-rc6"

substrate/Cargo.toml

@@ -88,6 +88,7 @@ members = [
 	"frame/metadata",
 	"frame/multisig",
 	"frame/nicks",
+	"frame/node-authorization",
 	"frame/offences",
 	"frame/proxy",
 	"frame/randomness-collective-flip",

substrate/client/network/src/service.rs

@@ -20,7 +20,7 @@
 //!
 //! There are two main structs in this module: [`NetworkWorker`] and [`NetworkService`].
 //! The [`NetworkWorker`] *is* the network and implements the `Future` trait. It must be polled in
-//! order fo the network to advance.
+//! order for the network to advance.
 //! The [`NetworkService`] is merely a shared version of the [`NetworkWorker`]. You can obtain an
 //! `Arc<NetworkService>` by calling [`NetworkWorker::service`].
 //!
@@ -605,6 +605,22 @@ impl<B: BlockT + 'static, H: ExHashT> NetworkService<B, H> {
 		&self.local_peer_id
 	}
 
+	/// Set authorized peers.
+	///
+	/// Need a better solution to manage authorized peers, but now just use reserved peers for
+	/// prototyping.
+	pub fn set_authorized_peers(&self, peers: HashSet<PeerId>) {
+		self.peerset.set_reserved_peers(peers)
+	}
+
+	/// Set authorized_only flag.
+	///
+	/// Need a better solution to decide authorized_only, but now just use reserved_only flag for
+	/// prototyping.
+	pub fn set_authorized_only(&self, reserved_only: bool) {
+		self.peerset.set_reserved_only(reserved_only)
+	}
+
 	/// Appends a notification to the buffer of pending outgoing notifications with the given peer.
 	/// Has no effect if the notifications channel with this protocol name is not open.
 	///

substrate/client/offchain/src/api.rs

@@ -19,16 +19,18 @@ use std::{
 	sync::Arc,
 	convert::TryFrom,
 	thread::sleep,
+	collections::HashSet,
 };
 
-use sp_core::offchain::OffchainStorage;
+use crate::NetworkProvider;
 use futures::Future;
 use log::error;
-use sc_network::{PeerId, Multiaddr, NetworkStateInfo};
+use sc_network::{PeerId, Multiaddr};
 use codec::{Encode, Decode};
+use sp_core::OpaquePeerId;
 use sp_core::offchain::{
 	Externalities as OffchainExt, HttpRequestId, Timestamp, HttpRequestStatus, HttpError,
-	OpaqueNetworkState, OpaquePeerId, OpaqueMultiaddr, StorageKind,
+	OffchainStorage, OpaqueNetworkState, OpaqueMultiaddr, StorageKind,
 };
 pub use sp_offchain::STORAGE_PREFIX;
 pub use http::SharedClient;
@@ -49,8 +51,8 @@ mod timestamp;
 pub(crate) struct Api<Storage> {
 	/// Offchain Workers database.
 	db: Storage,
-	/// A NetworkState provider.
-	network_state: Arc<dyn NetworkStateInfo + Send + Sync>,
+	/// A provider for substrate networking.
+	network_provider: Arc<dyn NetworkProvider + Send + Sync>,
 	/// Is this node a potential validator?
 	is_validator: bool,
 	/// Everything HTTP-related is handled by a different struct.
@@ -73,10 +75,10 @@ impl<Storage: OffchainStorage> OffchainExt for Api<Storage> {
 	}
 
 	fn network_state(&self) -> Result<OpaqueNetworkState, ()> {
-		let external_addresses = self.network_state.external_addresses();
+		let external_addresses = self.network_provider.external_addresses();
 
 		let state = NetworkState::new(
-			self.network_state.local_peer_id(),
+			self.network_provider.local_peer_id(),
 			external_addresses,
 		);
 		Ok(OpaqueNetworkState::from(state))
@@ -180,6 +182,15 @@ impl<Storage: OffchainStorage> OffchainExt for Api<Storage> {
 	) -> Result<usize, HttpError> {
 		self.http.response_read_body(request_id, buffer, deadline)
 	}
+
+	fn set_authorized_nodes(&mut self, nodes: Vec<OpaquePeerId>, authorized_only: bool) {
+		let peer_ids: HashSet<PeerId> = nodes.into_iter()
+			.filter_map(|node| PeerId::from_bytes(node.0).ok())
+			.collect();
+		
+		self.network_provider.set_authorized_peers(peer_ids);
+		self.network_provider.set_authorized_only(authorized_only);
+	}
 }
 
 /// Information about the local node's network state.
@@ -256,10 +267,10 @@ pub(crate) struct AsyncApi {
 }
 
 impl AsyncApi {
-	/// Creates new Offchain extensions API implementation  an the asynchronous processing part.
+	/// Creates new Offchain extensions API implementation an the asynchronous processing part.
 	pub fn new<S: OffchainStorage>(
 		db: S,
-		network_state: Arc<dyn NetworkStateInfo + Send + Sync>,
+		network_provider: Arc<dyn NetworkProvider + Send + Sync>,
 		is_validator: bool,
 		shared_client: SharedClient,
 	) -> (Api<S>, Self) {
@@ -267,7 +278,7 @@ impl AsyncApi {
 
 		let api = Api {
 			db,
-			network_state,
+			network_provider,
 			is_validator,
 			http: http_api,
 		};
@@ -292,11 +303,21 @@ mod tests {
 	use super::*;
 	use std::{convert::{TryFrom, TryInto}, time::SystemTime};
 	use sc_client_db::offchain::LocalStorage;
-	use sc_network::PeerId;
+	use sc_network::{NetworkStateInfo, PeerId};
 
-	struct MockNetworkStateInfo();
+	struct TestNetwork();
 
-	impl NetworkStateInfo for MockNetworkStateInfo {
+	impl NetworkProvider for TestNetwork {
+		fn set_authorized_peers(&self, _peers: HashSet<PeerId>) {
+			unimplemented!()
+		}
+
+		fn set_authorized_only(&self, _reserved_only: bool) {
+			unimplemented!()
+		}
+	}
+
+	impl NetworkStateInfo for TestNetwork {
 		fn external_addresses(&self) -> Vec<Multiaddr> {
 			Vec::new()
 		}
@@ -309,10 +330,9 @@ mod tests {
 	fn offchain_api() -> (Api<LocalStorage>, AsyncApi) {
 		let _ = env_logger::try_init();
 		let db = LocalStorage::new_test();
-		let mock = Arc::new(MockNetworkStateInfo());
+		let mock = Arc::new(TestNetwork());
 		let shared_client = SharedClient::new();
 
-
 		AsyncApi::new(
 			db,
 			mock,

substrate/client/offchain/src/lib.rs

@@ -33,14 +33,17 @@
 
 #![warn(missing_docs)]
 
-use std::{fmt, marker::PhantomData, sync::Arc};
+use std::{
+	fmt, marker::PhantomData, sync::Arc,
+	collections::HashSet,
+};
 
 use parking_lot::Mutex;
 use threadpool::ThreadPool;
 use sp_api::{ApiExt, ProvideRuntimeApi};
 use futures::future::Future;
 use log::{debug, warn};
-use sc_network::NetworkStateInfo;
+use sc_network::{ExHashT, NetworkService, NetworkStateInfo, PeerId};
 use sp_core::{offchain::{self, OffchainStorage}, ExecutionContext, traits::SpawnNamed};
 use sp_runtime::{generic::BlockId, traits::{self, Header}};
 use futures::{prelude::*, future::ready};
@@ -50,6 +53,30 @@ use api::SharedClient;
 
 pub use sp_offchain::{OffchainWorkerApi, STORAGE_PREFIX};
 
+/// NetworkProvider provides [`OffchainWorkers`] with all necessary hooks into the
+/// underlying Substrate networking.
+pub trait NetworkProvider: NetworkStateInfo {
+	/// Set the authorized peers.
+	fn set_authorized_peers(&self, peers: HashSet<PeerId>);
+	
+	/// Set the authorized only flag.
+	fn set_authorized_only(&self, reserved_only: bool);
+}
+
+impl<B, H> NetworkProvider for NetworkService<B, H>
+where
+	B: traits::Block + 'static,
+	H: ExHashT,
+{
+	fn set_authorized_peers(&self, peers: HashSet<PeerId>) {
+		self.set_authorized_peers(peers)
+	}
+
+	fn set_authorized_only(&self, reserved_only: bool) {
+		self.set_authorized_only(reserved_only)
+	}
+}
+
 /// An offchain workers manager.
 pub struct OffchainWorkers<Client, Storage, Block: traits::Block> {
 	client: Arc<Client>,
@@ -98,7 +125,7 @@ impl<Client, Storage, Block> OffchainWorkers<
 	pub fn on_block_imported(
 		&self,
 		header: &Block::Header,
-		network_state: Arc<dyn NetworkStateInfo + Send + Sync>,
+		network_provider: Arc<dyn NetworkProvider + Send + Sync>,
 		is_validator: bool,
 	) -> impl Future<Output = ()> {
 		let runtime = self.client.runtime_api();
@@ -122,7 +149,7 @@ impl<Client, Storage, Block> OffchainWorkers<
 		if version > 0 {
 			let (api, runner) = api::AsyncApi::new(
 				self.db.clone(),
-				network_state.clone(),
+				network_provider,
 				is_validator,
 				self.shared_client.clone(),
 			);
@@ -173,7 +200,7 @@ pub async fn notification_future<Client, Storage, Block, Spawner>(
 	client: Arc<Client>,
 	offchain: Arc<OffchainWorkers<Client, Storage, Block>>,
 	spawner: Spawner,
-	network_state_info: Arc<dyn NetworkStateInfo + Send + Sync>,
+	network_provider: Arc<dyn NetworkProvider + Send + Sync>,
 )
 	where
 		Block: traits::Block,
@@ -188,7 +215,7 @@ pub async fn notification_future<Client, Storage, Block, Spawner>(
 				"offchain-on-block",
 				offchain.on_block_imported(
 					&n.header,
-					network_state_info.clone(),
+					network_provider.clone(),
 					is_validator,
 				).boxed(),
 			);
@@ -213,9 +240,9 @@ mod tests {
 	use sc_transaction_pool::{BasicPool, FullChainApi};
 	use sp_transaction_pool::{TransactionPool, InPoolTransaction};
 
-	struct MockNetworkStateInfo();
+	struct TestNetwork();
 
-	impl NetworkStateInfo for MockNetworkStateInfo {
+	impl NetworkStateInfo for TestNetwork {
 		fn external_addresses(&self) -> Vec<Multiaddr> {
 			Vec::new()
 		}
@@ -225,6 +252,16 @@ mod tests {
 		}
 	}
 
+	impl NetworkProvider for TestNetwork {
+		fn set_authorized_peers(&self, _peers: HashSet<PeerId>) {
+			unimplemented!()
+		}
+
+		fn set_authorized_only(&self, _reserved_only: bool) {
+			unimplemented!()
+		}
+	}
+
 	struct TestPool(
 		Arc<BasicPool<FullChainApi<TestClient, Block>, Block>>
 	);
@@ -255,12 +292,14 @@ mod tests {
 			client.clone(),
 		));
 		let db = sc_client_db::offchain::LocalStorage::new_test();
-		let network_state = Arc::new(MockNetworkStateInfo());
+		let network = Arc::new(TestNetwork());
 		let header = client.header(&BlockId::number(0)).unwrap().unwrap();
 
 		// when
 		let offchain = OffchainWorkers::new(client, db);
-		futures::executor::block_on(offchain.on_block_imported(&header, network_state, false));
+		futures::executor::block_on(
+			offchain.on_block_imported(&header, network, false)
+		);
 
 		// then
 		assert_eq!(pool.0.status().ready, 1);

substrate/client/peerset/src/lib.rs

@@ -45,6 +45,7 @@ const FORGET_AFTER: Duration = Duration::from_secs(3600);
 enum Action {
 	AddReservedPeer(PeerId),
 	RemoveReservedPeer(PeerId),
+	SetReservedPeers(HashSet<PeerId>),
 	SetReservedOnly(bool),
 	ReportPeer(PeerId, ReputationChange),
 	SetPriorityGroup(String, HashSet<PeerId>),
@@ -102,6 +103,11 @@ impl PeersetHandle {
 	pub fn set_reserved_only(&self, reserved: bool) {
 		let _ = self.tx.unbounded_send(Action::SetReservedOnly(reserved));
 	}
+	
+	/// Set reserved peers to the new set.
+	pub fn set_reserved_peers(&self, peer_ids: HashSet<PeerId>) {
+		let _ = self.tx.unbounded_send(Action::SetReservedPeers(peer_ids));
+	}
 
 	/// Reports an adjustment to the reputation of the given peer.
 	pub fn report_peer(&self, peer_id: PeerId, score_diff: ReputationChange) {
@@ -246,6 +252,10 @@ impl Peerset {
 	fn on_remove_reserved_peer(&mut self, peer_id: PeerId) {
 		self.on_remove_from_priority_group(RESERVED_NODES, peer_id);
 	}
+	
+	fn on_set_reserved_peers(&mut self, peer_ids: HashSet<PeerId>) {
+		self.on_set_priority_group(RESERVED_NODES, peer_ids);
+	}
 
 	fn on_set_reserved_only(&mut self, reserved_only: bool) {
 		self.reserved_only = reserved_only;
@@ -655,6 +665,8 @@ impl Stream for Peerset {
 					self.on_add_reserved_peer(peer_id),
 				Action::RemoveReservedPeer(peer_id) =>
 					self.on_remove_reserved_peer(peer_id),
+				Action::SetReservedPeers(peer_ids) =>
+					self.on_set_reserved_peers(peer_ids),
 				Action::SetReservedOnly(reserved) =>
 					self.on_set_reserved_only(reserved),
 				Action::ReportPeer(peer_id, score_diff) =>

substrate/client/service/src/builder.rs

@@ -431,7 +431,7 @@ pub fn build_offchain_workers<TBl, TBackend, TCl>(
 				client.clone(),
 				offchain,
 				Clone::clone(&spawn_handle),
-				network.clone()
+				network.clone(),
 			)
 		);
 	}

substrate/frame/im-online/src/benchmarking.rs

@@ -23,7 +23,8 @@ use super::*;
 
 use frame_system::RawOrigin;
 use frame_benchmarking::benchmarks;
-use sp_core::offchain::{OpaquePeerId, OpaqueMultiaddr};
+use sp_core::OpaquePeerId;
+use sp_core::offchain::OpaqueMultiaddr;
 use sp_runtime::traits::{ValidateUnsigned, Zero};
 use sp_runtime::transaction_validity::TransactionSource;
 use frame_support::traits::UnfilteredDispatchable;

substrate/frame/im-online/src/tests.rs

@@ -21,8 +21,8 @@
 
 use super::*;
 use crate::mock::*;
+use sp_core::OpaquePeerId;
 use sp_core::offchain::{
-	OpaquePeerId,
 	OffchainExt,
 	TransactionPoolExt,
 	testing::{TestOffchainExt, TestTransactionPoolExt},

substrate/frame/node-authorization/Cargo.toml

@@ -0,0 +1,35 @@
+[package]
+name = "pallet-node-authorization"
+version = "2.0.0-rc6"
+authors = ["Parity Technologies <admin@parity.io>"]
+edition = "2018"
+license = "Apache-2.0"
+homepage = "https://substrate.dev"
+repository = "https://github.com/paritytech/substrate/"
+description = "FRAME pallet for node authorization"
+
+[package.metadata.docs.rs]
+targets = ["x86_64-unknown-linux-gnu"]
+
+[dependencies]
+serde = { version = "1.0.101", optional = true }
+codec = { package = "parity-scale-codec", version = "1.3.4", default-features = false, features = ["derive"] }
+frame-support = { version = "2.0.0-rc6", default-features = false, path = "../support" }
+frame-system = { version = "2.0.0-rc6", default-features = false, path = "../system" }
+sp-core = { version = "2.0.0-rc6", default-features = false, path = "../../primitives/core" }
+sp-io = { version = "2.0.0-rc6", default-features = false, path = "../../primitives/io" }
+sp-runtime = { version = "2.0.0-rc6", default-features = false, path = "../../primitives/runtime" }
+sp-std = { version = "2.0.0-rc6", default-features = false, path = "../../primitives/std" }
+
+[features]
+default = ["std"]
+std = [
+	"serde",
+	"codec/std",
+	"frame-support/std",
+	"frame-system/std",
+	"sp-core/std",
+	"sp-io/std",
+	"sp-runtime/std",
+	"sp-std/std",
+]

substrate/frame/node-authorization/src/lib.rs

@@ -0,0 +1,861 @@
+// This file is part of Substrate.
+
+// Copyright (C) 2019-2020 Parity Technologies (UK) Ltd.
+// SPDX-License-Identifier: Apache-2.0
+
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//! # Node authorization pallet
+//!
+//! This pallet manages a configurable set of nodes for a permissioned network.
+//! Each node is dentified by a PeerId (i.e. Vec<u8>). It provides two ways to
+//! authorize a node,
+//!
+//! - a set of well known nodes across different organizations in which the
+//! connections are allowed.
+//! - users can claim the ownership for each node, then manage the connections of
+//! the node.
+//!
+//! A node must have an owner. The owner can additionally change the connections
+//! for the node. Only one user is allowed to claim a specific node. To eliminate
+//! false claim, the maintainer of the node should claim it before even starting the
+//! node. This pallet uses offchain worker to set reserved nodes, if the node is not
+//! an authority, make sure to enable offchain worker with the right CLI flag. The
+//! node can be lagged with the latest block, in this case you need to disable offchain
+//! worker and manually set reserved nodes when starting it.
+
+// Ensure we're `no_std` when compiling for Wasm.
+#![cfg_attr(not(feature = "std"), no_std)]
+
+use sp_core::OpaquePeerId as PeerId;
+use sp_std::{
+	collections::btree_set::BTreeSet,
+	iter::FromIterator,
+	prelude::*,
+};
+use codec::Decode;
+use frame_support::{
+	decl_module, decl_storage, decl_event, decl_error,
+	debug, ensure,
+	weights::{DispatchClass, Weight},
+	traits::{Get, EnsureOrigin},
+};
+use frame_system::ensure_signed;
+
+pub trait WeightInfo {
+	fn add_well_known_node() -> Weight;
+	fn remove_well_known_node() -> Weight;
+	fn swap_well_known_node() -> Weight;
+	fn reset_well_known_nodes() -> Weight;
+	fn claim_node() -> Weight;
+	fn remove_claim() -> Weight;
+	fn transfer_node() -> Weight;
+	fn add_connections() -> Weight;
+	fn remove_connections() -> Weight;
+}
+
+impl WeightInfo for () {
+	fn add_well_known_node() -> Weight { 50_000_000 }
+	fn remove_well_known_node() -> Weight { 50_000_000 }
+	fn swap_well_known_node() -> Weight { 50_000_000 }
+	fn reset_well_known_nodes() -> Weight { 50_000_000 }
+	fn claim_node() -> Weight { 50_000_000 }
+	fn remove_claim() -> Weight { 50_000_000 }
+	fn transfer_node() -> Weight { 50_000_000 }
+	fn add_connections() -> Weight { 50_000_000 }
+	fn remove_connections() -> Weight { 50_000_000 }
+}
+
+pub trait Trait: frame_system::Trait {
+	/// The event type of this module.
+	type Event: From<Event<Self>> + Into<<Self as frame_system::Trait>::Event>;
+
+	/// The maximum number of well known nodes that are allowed to set
+	type MaxWellKnownNodes: Get<u32>;
+
+	/// The maximum length in bytes of PeerId
+	type MaxPeerIdLength: Get<u32>;
+
+	/// The origin which can add a well known node.
+	type AddOrigin: EnsureOrigin<Self::Origin>;
+
+	/// The origin which can remove a well known node.
+	type RemoveOrigin: EnsureOrigin<Self::Origin>;
+
+	/// The origin which can swap the well known nodes.
+	type SwapOrigin: EnsureOrigin<Self::Origin>;
+
+	/// The origin which can reset the well known nodes.
+	type ResetOrigin: EnsureOrigin<Self::Origin>;
+
+	/// Weight information for extrinsics in this pallet.
+	type WeightInfo: WeightInfo;
+}
+
+decl_storage! {
+	trait Store for Module<T: Trait> as NodeAuthorization {
+		/// The set of well known nodes. This is stored sorted (just by value).
+		pub WellKnownNodes get(fn well_known_nodes): BTreeSet<PeerId>;
+		/// A map that maintains the ownership of each node.
+		pub Owners get(fn owners):
+			map hasher(blake2_128_concat) PeerId => T::AccountId;
+		/// The additional adapative connections of each node.
+		pub AdditionalConnections get(fn additional_connection):
+			map hasher(blake2_128_concat) PeerId => BTreeSet<PeerId>;
+	}
+	add_extra_genesis {
+		config(nodes): Vec<(PeerId, T::AccountId)>;
+		build(|config: &GenesisConfig<T>| {
+			<Module<T>>::initialize_nodes(&config.nodes)
+		})
+	}
+}
+
+decl_event! {
+	pub enum Event<T> where
+		<T as frame_system::Trait>::AccountId,
+	{
+		/// The given well known node was added.
+		NodeAdded(PeerId, AccountId),
+		/// The given well known node was removed.
+		NodeRemoved(PeerId),
+		/// The given well known node was swapped; first item was removed,
+		/// the latter was added.
+		NodeSwapped(PeerId, PeerId),
+		/// The given well known nodes were reset.
+		NodesReset(Vec<(PeerId, AccountId)>),
+		/// The given node was claimed by a user.
+		NodeClaimed(PeerId, AccountId),
+		/// The given claim was removed by its owner.
+		ClaimRemoved(PeerId, AccountId),
+		/// The node was transferred to another account.
+		NodeTransferred(PeerId, AccountId),
+		/// The allowed connections were added to a node.
+		ConnectionsAdded(PeerId, Vec<PeerId>),
+		/// The allowed connections were removed from a node.
+		ConnectionsRemoved(PeerId, Vec<PeerId>),
+	}
+}
+
+decl_error! {
+	/// Error for the node authorization module.
+	pub enum Error for Module<T: Trait> {
+		/// The PeerId is too long.
+		PeerIdTooLong,
+		/// Too many well known nodes.
+		TooManyNodes,
+		/// The node is already joined in the list.
+		AlreadyJoined,
+		/// The node doesn't exist in the list.
+		NotExist,
+		/// The node is already claimed by a user.
+		AlreadyClaimed,
+		/// The node hasn't been claimed yet.
+		NotClaimed,
+		/// You are not the owner of the node.
+		NotOwner,
+		/// No permisson to perform specific operation.
+		PermissionDenied,
+	}
+}
+
+decl_module! {
+	pub struct Module<T: Trait> for enum Call where origin: T::Origin {
+		/// The maximum number of authorized well known nodes
+		const MaxWellKnownNodes: u32 = T::MaxWellKnownNodes::get();
+
+		/// The maximum length in bytes of PeerId
+		const MaxPeerIdLength: u32 = T::MaxPeerIdLength::get();
+
+		type Error = Error<T>;
+
+		fn deposit_event() = default;
+
+		/// Add a node to the set of well known nodes. If the node is already claimed, the owner
+		/// will be updated and keep the existing additional connection unchanged.
+		///
+		/// May only be called from `T::AddOrigin`.
+		///
+		/// - `node`: identifier of the node.
+		#[weight = (T::WeightInfo::add_well_known_node(), DispatchClass::Operational)]
+		pub fn add_well_known_node(origin, node: PeerId, owner: T::AccountId) {
+			T::AddOrigin::ensure_origin(origin)?;
+			ensure!(node.0.len() < T::MaxPeerIdLength::get() as usize, Error::<T>::PeerIdTooLong);
+
+			let mut nodes = WellKnownNodes::get();
+			ensure!(nodes.len() < T::MaxWellKnownNodes::get() as usize, Error::<T>::TooManyNodes);
+			ensure!(!nodes.contains(&node), Error::<T>::AlreadyJoined);
+
+			nodes.insert(node.clone());
+
+			WellKnownNodes::put(&nodes);
+			<Owners<T>>::insert(&node, &owner);
+
+			Self::deposit_event(RawEvent::NodeAdded(node, owner));
+		}
+
+		/// Remove a node from the set of well known nodes. The ownership and additional
+		/// connections of the node will also be removed.
+		///
+		/// May only be called from `T::RemoveOrigin`.
+		///
+		/// - `node`: identifier of the node.
+		#[weight = (T::WeightInfo::remove_well_known_node(), DispatchClass::Operational)]
+		pub fn remove_well_known_node(origin, node: PeerId) {
+			T::RemoveOrigin::ensure_origin(origin)?;
+			ensure!(node.0.len() < T::MaxPeerIdLength::get() as usize, Error::<T>::PeerIdTooLong);
+
+			let mut nodes = WellKnownNodes::get();
+			ensure!(nodes.contains(&node), Error::<T>::NotExist);
+
+			nodes.remove(&node);
+
+			WellKnownNodes::put(&nodes);
+			<Owners<T>>::remove(&node);
+			AdditionalConnections::remove(&node);
+
+			Self::deposit_event(RawEvent::NodeRemoved(node));
+		}
+
+		/// Swap a well known node to another. Both the ownership and additional connections
+		/// stay untouched.
+		///
+		/// May only be called from `T::SwapOrigin`.
+		///
+		/// - `remove`: the node which will be moved out from the list.
+		/// - `add`: the node which will be put in the list.
+		#[weight = (T::WeightInfo::swap_well_known_node(), DispatchClass::Operational)]
+		pub fn swap_well_known_node(origin, remove: PeerId, add: PeerId) {
+			T::SwapOrigin::ensure_origin(origin)?;
+			ensure!(remove.0.len() < T::MaxPeerIdLength::get() as usize, Error::<T>::PeerIdTooLong);
+			ensure!(add.0.len() < T::MaxPeerIdLength::get() as usize, Error::<T>::PeerIdTooLong);
+
+			if remove == add { return Ok(()) }
+
+			let mut nodes = WellKnownNodes::get();
+			ensure!(nodes.contains(&remove), Error::<T>::NotExist);
+			ensure!(!nodes.contains(&add), Error::<T>::AlreadyJoined);
+
+			nodes.remove(&remove);
+			nodes.insert(add.clone());
+
+			WellKnownNodes::put(&nodes);
+			Owners::<T>::swap(&remove, &add);
+			AdditionalConnections::swap(&remove, &add);
+
+			Self::deposit_event(RawEvent::NodeSwapped(remove, add));
+		}
+
+		/// Reset all the well known nodes. This will not remove the ownership and additional
+		/// connections for the removed nodes. The node owner can perform further cleaning if
+		/// they decide to leave the network.
+		///
+		/// May only be called from `T::ResetOrigin`.
+		///
+		/// - `nodes`: the new nodes for the allow list.
+		#[weight = (T::WeightInfo::reset_well_known_nodes(), DispatchClass::Operational)]
+		pub fn reset_well_known_nodes(origin, nodes: Vec<(PeerId, T::AccountId)>) {
+			T::ResetOrigin::ensure_origin(origin)?;
+			ensure!(nodes.len() < T::MaxWellKnownNodes::get() as usize, Error::<T>::TooManyNodes);
+	
+			Self::initialize_nodes(&nodes);
+
+			Self::deposit_event(RawEvent::NodesReset(nodes));
+		}
+
+		/// A given node can be claimed by anyone. The owner should be the first to know its
+		/// PeerId, so claim it right away!
+		///
+		/// - `node`: identifier of the node.
+		#[weight = T::WeightInfo::claim_node()]
+		pub fn claim_node(origin, node: PeerId) {
+			let sender = ensure_signed(origin)?;
+			
+			ensure!(node.0.len() < T::MaxPeerIdLength::get() as usize, Error::<T>::PeerIdTooLong);
+			ensure!(!Owners::<T>::contains_key(&node),Error::<T>::AlreadyClaimed);
+
+			Owners::<T>::insert(&node, &sender);
+			Self::deposit_event(RawEvent::NodeClaimed(node, sender));
+		}
+
+		/// A claim can be removed by its owner and get back the reservation. The additional
+		/// connections are also removed. You can't remove a claim on well known nodes, as it
+		/// needs to reach consensus among the network participants.
+		///
+		/// - `node`: identifier of the node.
+		#[weight = T::WeightInfo::remove_claim()]
+		pub fn remove_claim(origin, node: PeerId) {
+			let sender = ensure_signed(origin)?;
+
+			ensure!(node.0.len() < T::MaxPeerIdLength::get() as usize, Error::<T>::PeerIdTooLong);
+			ensure!(Owners::<T>::contains_key(&node), Error::<T>::NotClaimed);
+			ensure!(Owners::<T>::get(&node) == sender, Error::<T>::NotOwner);
+			ensure!(!WellKnownNodes::get().contains(&node), Error::<T>::PermissionDenied);
+
+			Owners::<T>::remove(&node);
+			AdditionalConnections::remove(&node);
+
+			Self::deposit_event(RawEvent::ClaimRemoved(node, sender));
+		}
+
+		/// A node can be transferred to a new owner.
+		///
+		/// - `node`: identifier of the node.
+		/// - `owner`: new owner of the node.
+		#[weight = T::WeightInfo::transfer_node()]
+		pub fn transfer_node(origin, node: PeerId, owner: T::AccountId) {
+			let sender = ensure_signed(origin)?;
+
+			ensure!(node.0.len() < T::MaxPeerIdLength::get() as usize, Error::<T>::PeerIdTooLong);
+			ensure!(Owners::<T>::contains_key(&node), Error::<T>::NotClaimed);
+			ensure!(Owners::<T>::get(&node) == sender, Error::<T>::NotOwner);
+
+			Owners::<T>::insert(&node, &owner);
+
+			Self::deposit_event(RawEvent::NodeTransferred(node, owner));
+		}
+
+		/// Add additional connections to a given node.
+		///
+		/// - `node`: identifier of the node.
+		/// - `connections`: additonal nodes from which the connections are allowed.
+		#[weight = T::WeightInfo::add_connections()]
+		pub fn add_connections(
+			origin,
+			node: PeerId,
+			connections: Vec<PeerId>
+		) {
+			let sender = ensure_signed(origin)?;
+
+			ensure!(node.0.len() < T::MaxPeerIdLength::get() as usize, Error::<T>::PeerIdTooLong);
+			ensure!(Owners::<T>::contains_key(&node), Error::<T>::NotClaimed);
+			ensure!(Owners::<T>::get(&node) == sender, Error::<T>::NotOwner);
+
+			let mut nodes = AdditionalConnections::get(&node);
+
+			for add_node in connections.iter() {
+				if *add_node == node {
+					continue;
+				}
+				nodes.insert(add_node.clone());
+			}
+
+			AdditionalConnections::insert(&node, nodes);
+
+			Self::deposit_event(RawEvent::ConnectionsAdded(node, connections));
+		}
+
+		/// Remove additional connections of a given node.
+		///
+		/// - `node`: identifier of the node.
+		/// - `connections`: additonal nodes from which the connections are not allowed anymore.
+		#[weight = T::WeightInfo::remove_connections()]
+		pub fn remove_connections(
+			origin,
+			node: PeerId,
+			connections: Vec<PeerId>
+		) {
+			let sender = ensure_signed(origin)?;
+
+			ensure!(node.0.len() < T::MaxPeerIdLength::get() as usize, Error::<T>::PeerIdTooLong);
+			ensure!(Owners::<T>::contains_key(&node), Error::<T>::NotClaimed);
+			ensure!(Owners::<T>::get(&node) == sender, Error::<T>::NotOwner);
+
+			let mut nodes = AdditionalConnections::get(&node);
+
+			for remove_node in connections.iter() {
+				nodes.remove(remove_node);
+			}
+
+			AdditionalConnections::insert(&node, nodes);
+
+			Self::deposit_event(RawEvent::ConnectionsRemoved(node, connections));
+		}
+
+		/// Set reserved node every block. It may not be enabled depends on the offchain
+		/// worker settings when starting the node.
+		fn offchain_worker(now: T::BlockNumber) {
+			let network_state = sp_io::offchain::network_state();
+			match network_state {
+				Err(_) => debug::error!("Error: failed to get network state of node at {:?}", now),
+				Ok(state) => {
+					let encoded_peer = state.peer_id.0;
+					match Decode::decode(&mut &encoded_peer[..]) {
+						Err(_) => debug::error!("Error: failed to decode PeerId at {:?}", now),
+						Ok(node) => sp_io::offchain::set_authorized_nodes(
+							Self::get_authorized_nodes(&PeerId(node)),
+							true
+						)
+					}
+				}
+			}
+		}
+	}
+}
+
+impl<T: Trait> Module<T> {
+	fn initialize_nodes(nodes: &Vec<(PeerId, T::AccountId)>) {
+		let peer_ids = nodes.iter()
+			.map(|item| item.0.clone())
+			.collect::<BTreeSet<PeerId>>();
+		WellKnownNodes::put(&peer_ids);
+
+		for (node, who) in nodes.iter() {
+			Owners::<T>::insert(node, who);
+		}
+	}
+
+	fn get_authorized_nodes(node: &PeerId) -> Vec<PeerId> {
+		let mut nodes = AdditionalConnections::get(node);
+
+		let mut well_known_nodes = WellKnownNodes::get();
+		if well_known_nodes.contains(node) {
+			well_known_nodes.remove(node);
+			nodes.extend(well_known_nodes);
+		}
+
+		Vec::from_iter(nodes)
+	}
+}
+
+#[cfg(test)]
+mod tests {
+	use super::*;
+
+	use frame_support::{
+		assert_ok, assert_noop, impl_outer_origin, weights::Weight,
+		parameter_types, ord_parameter_types,
+	};
+	use frame_system::EnsureSignedBy;
+	use sp_core::H256;
+	use sp_runtime::{Perbill, traits::{BlakeTwo256, IdentityLookup, BadOrigin}, testing::Header};
+
+	impl_outer_origin! {
+		pub enum Origin for Test where system = frame_system {}
+	}
+
+	#[derive(Clone, Eq, PartialEq)]
+	pub struct Test;
+
+	parameter_types! {
+		pub const BlockHashCount: u64 = 250;
+		pub const MaximumBlockWeight: Weight = 1024;
+		pub const MaximumBlockLength: u32 = 2 * 1024;
+		pub const AvailableBlockRatio: Perbill = Perbill::one();
+	}
+	impl frame_system::Trait for Test {
+		type BaseCallFilter = ();
+		type Origin = Origin;
+		type Index = u64;
+		type BlockNumber = u64;
+		type Hash = H256;
+		type Call = ();
+		type Hashing = BlakeTwo256;
+		type AccountId = u64;
+		type Lookup = IdentityLookup<Self::AccountId>;
+		type Header = Header;
+		type Event = ();
+		type BlockHashCount = BlockHashCount;
+		type MaximumBlockWeight = MaximumBlockWeight;
+		type DbWeight = ();
+		type BlockExecutionWeight = ();
+		type ExtrinsicBaseWeight = ();
+		type MaximumExtrinsicWeight = MaximumBlockWeight;
+		type MaximumBlockLength = MaximumBlockLength;
+		type AvailableBlockRatio = AvailableBlockRatio;
+		type Version = ();
+		type ModuleToIndex = ();
+		type AccountData = ();
+		type OnNewAccount = ();
+		type OnKilledAccount = ();
+		type SystemWeightInfo = ();
+	}
+
+	ord_parameter_types! {
+		pub const One: u64 = 1;
+		pub const Two: u64 = 2;
+		pub const Three: u64 = 3;
+		pub const Four: u64 = 4;
+	}
+	parameter_types! {
+		pub const MaxWellKnownNodes: u32 = 4;
+		pub const MaxPeerIdLength: u32 = 2;
+	}
+	impl Trait for Test {
+		type Event = ();
+		type MaxWellKnownNodes = MaxWellKnownNodes;
+		type MaxPeerIdLength = MaxPeerIdLength;
+		type AddOrigin = EnsureSignedBy<One, u64>;
+		type RemoveOrigin = EnsureSignedBy<Two, u64>;
+		type SwapOrigin = EnsureSignedBy<Three, u64>;
+		type ResetOrigin = EnsureSignedBy<Four, u64>;
+		type WeightInfo = ();
+	}
+
+	type NodeAuthorization = Module<Test>;
+
+	fn test_node(id: u8) -> PeerId {
+		PeerId(vec![id])
+	}
+
+	fn new_test_ext() -> sp_io::TestExternalities {
+		let mut t = frame_system::GenesisConfig::default().build_storage::<Test>().unwrap();
+		GenesisConfig::<Test> {
+			nodes: vec![(test_node(10), 10), (test_node(20), 20), (test_node(30), 30)],
+		}.assimilate_storage(&mut t).unwrap();
+		t.into()
+	}
+
+	#[test]
+	fn add_well_known_node_works() {
+		new_test_ext().execute_with(|| {
+			assert_noop!(
+				NodeAuthorization::add_well_known_node(Origin::signed(2), test_node(15), 15),
+				BadOrigin
+			);
+			assert_noop!(
+				NodeAuthorization::add_well_known_node(Origin::signed(1), PeerId(vec![1, 2, 3]), 15),
+				Error::<Test>::PeerIdTooLong
+			);
+			assert_noop!(
+				NodeAuthorization::add_well_known_node(Origin::signed(1), test_node(20), 20),
+				Error::<Test>::AlreadyJoined
+			);
+
+			assert_ok!(
+				NodeAuthorization::add_well_known_node(Origin::signed(1), test_node(15), 15)
+			);
+			assert_eq!(
+				WellKnownNodes::get(),
+				BTreeSet::from_iter(vec![test_node(10), test_node(15), test_node(20), test_node(30)])
+			);
+			assert_eq!(Owners::<Test>::get(test_node(10)), 10);
+			assert_eq!(Owners::<Test>::get(test_node(20)), 20);
+			assert_eq!(Owners::<Test>::get(test_node(30)), 30);
+			assert_eq!(Owners::<Test>::get(test_node(15)), 15);
+
+			assert_noop!(
+				NodeAuthorization::add_well_known_node(Origin::signed(1), test_node(25), 25),
+				Error::<Test>::TooManyNodes
+			);
+		});
+	}
+
+	#[test]
+	fn remove_well_known_node_works() {
+		new_test_ext().execute_with(|| {
+			assert_noop!(
+				NodeAuthorization::remove_well_known_node(Origin::signed(3), test_node(20)),
+				BadOrigin
+			);
+			assert_noop!(
+				NodeAuthorization::remove_well_known_node(Origin::signed(2), PeerId(vec![1, 2, 3])),
+				Error::<Test>::PeerIdTooLong
+			);
+			assert_noop!(
+				NodeAuthorization::remove_well_known_node(Origin::signed(2), test_node(40)),
+				Error::<Test>::NotExist
+			);
+
+			AdditionalConnections::insert(
+				test_node(20),
+				BTreeSet::from_iter(vec![test_node(40)])
+			);
+			assert!(AdditionalConnections::contains_key(test_node(20)));
+
+			assert_ok!(
+				NodeAuthorization::remove_well_known_node(Origin::signed(2), test_node(20))
+			);
+			assert_eq!(
+				WellKnownNodes::get(),
+				BTreeSet::from_iter(vec![test_node(10), test_node(30)])
+			);
+			assert!(!Owners::<Test>::contains_key(test_node(20)));
+			assert!(!AdditionalConnections::contains_key(test_node(20)));
+		});
+	}
+
+	#[test]
+	fn swap_well_known_node_works() {
+		new_test_ext().execute_with(|| {
+			assert_noop!(
+				NodeAuthorization::swap_well_known_node(
+					Origin::signed(4), test_node(20), test_node(5)
+				),
+				BadOrigin
+			);
+			assert_noop!(
+				NodeAuthorization::swap_well_known_node(
+					Origin::signed(3), PeerId(vec![1, 2, 3]), test_node(20)
+				),
+				Error::<Test>::PeerIdTooLong
+			);
+			assert_noop!(
+				NodeAuthorization::swap_well_known_node(
+					Origin::signed(3), test_node(20), PeerId(vec![1, 2, 3])
+				),
+				Error::<Test>::PeerIdTooLong
+			);
+
+			assert_ok!(
+				NodeAuthorization::swap_well_known_node(
+					Origin::signed(3), test_node(20), test_node(20)
+				)
+			);
+			assert_eq!(
+				WellKnownNodes::get(),
+				BTreeSet::from_iter(vec![test_node(10), test_node(20), test_node(30)])
+			);
+
+			assert_noop!(
+				NodeAuthorization::swap_well_known_node(
+					Origin::signed(3), test_node(15), test_node(5)
+				),
+				Error::<Test>::NotExist
+			);
+			assert_noop!(
+				NodeAuthorization::swap_well_known_node(
+					Origin::signed(3), test_node(20), test_node(30)
+				),
+				Error::<Test>::AlreadyJoined
+			);
+
+			AdditionalConnections::insert(
+				test_node(20),
+				BTreeSet::from_iter(vec![test_node(15)])
+			);
+			assert_ok!(
+				NodeAuthorization::swap_well_known_node(
+					Origin::signed(3), test_node(20), test_node(5)
+				)
+			);
+			assert_eq!(
+				WellKnownNodes::get(),
+				BTreeSet::from_iter(vec![test_node(5), test_node(10), test_node(30)])
+			);
+			assert!(!Owners::<Test>::contains_key(test_node(20)));
+			assert_eq!(Owners::<Test>::get(test_node(5)), 20);
+			assert!(!AdditionalConnections::contains_key(test_node(20)));
+			assert_eq!(
+				AdditionalConnections::get(test_node(5)),
+				BTreeSet::from_iter(vec![test_node(15)])
+			);
+		});
+	}
+
+	#[test]
+	fn reset_well_known_nodes_works() {
+		new_test_ext().execute_with(|| {
+			assert_noop!(
+				NodeAuthorization::reset_well_known_nodes(
+					Origin::signed(3),
+					vec![(test_node(15), 15), (test_node(5), 5), (test_node(20), 20)]
+				),
+				BadOrigin
+			);
+			assert_noop!(
+				NodeAuthorization::reset_well_known_nodes(
+					Origin::signed(4),
+					vec![
+						(test_node(15), 15),
+						(test_node(5), 5),
+						(test_node(20), 20),
+						(test_node(25), 25),
+					]
+				),
+				Error::<Test>::TooManyNodes
+			);
+
+			assert_ok!(
+				NodeAuthorization::reset_well_known_nodes(
+					Origin::signed(4),
+					vec![(test_node(15), 15), (test_node(5), 5), (test_node(20), 20)]
+				)
+			);
+			assert_eq!(
+				WellKnownNodes::get(),
+				BTreeSet::from_iter(vec![test_node(5), test_node(15), test_node(20)])
+			);
+			assert_eq!(Owners::<Test>::get(test_node(5)), 5);
+			assert_eq!(Owners::<Test>::get(test_node(15)), 15);
+			assert_eq!(Owners::<Test>::get(test_node(20)), 20);
+		});
+	}
+
+	#[test]
+	fn claim_node_works() {
+		new_test_ext().execute_with(|| {
+			assert_noop!(
+				NodeAuthorization::claim_node(Origin::signed(1), PeerId(vec![1, 2, 3])),
+				Error::<Test>::PeerIdTooLong
+			);
+			assert_noop!(
+				NodeAuthorization::claim_node(Origin::signed(1), test_node(20)),
+				Error::<Test>::AlreadyClaimed
+			);
+
+			assert_ok!(NodeAuthorization::claim_node(Origin::signed(15), test_node(15)));
+			assert_eq!(Owners::<Test>::get(test_node(15)), 15);
+		});
+	}
+
+	#[test]
+	fn remove_claim_works() {
+		new_test_ext().execute_with(|| {
+			assert_noop!(
+				NodeAuthorization::remove_claim(Origin::signed(15), PeerId(vec![1, 2, 3])),
+				Error::<Test>::PeerIdTooLong
+			);
+			assert_noop!(
+				NodeAuthorization::remove_claim(Origin::signed(15), test_node(15)),
+				Error::<Test>::NotClaimed
+			);
+
+			assert_noop!(
+				NodeAuthorization::remove_claim(Origin::signed(15), test_node(20)),
+				Error::<Test>::NotOwner
+			);
+
+			assert_noop!(
+				NodeAuthorization::remove_claim(Origin::signed(20), test_node(20)),
+				Error::<Test>::PermissionDenied
+			);
+
+			Owners::<Test>::insert(test_node(15), 15);
+			AdditionalConnections::insert(
+				test_node(15),
+				BTreeSet::from_iter(vec![test_node(20)])
+			);
+			assert_ok!(NodeAuthorization::remove_claim(Origin::signed(15), test_node(15)));
+			assert!(!Owners::<Test>::contains_key(test_node(15)));
+			assert!(!AdditionalConnections::contains_key(test_node(15)));
+		});
+	}
+
+	#[test]
+	fn transfer_node_works() {
+		new_test_ext().execute_with(|| {
+			assert_noop!(
+				NodeAuthorization::transfer_node(Origin::signed(15), PeerId(vec![1, 2, 3]), 10),
+				Error::<Test>::PeerIdTooLong
+			);
+			assert_noop!(
+				NodeAuthorization::transfer_node(Origin::signed(15), test_node(15), 10),
+				Error::<Test>::NotClaimed
+			);
+
+			assert_noop!(
+				NodeAuthorization::transfer_node(Origin::signed(15), test_node(20), 10),
+				Error::<Test>::NotOwner
+			);
+
+			assert_ok!(NodeAuthorization::transfer_node(Origin::signed(20), test_node(20), 15));
+			assert_eq!(Owners::<Test>::get(test_node(20)), 15);
+		});
+	}
+
+	#[test]
+	fn add_connections_works() {
+		new_test_ext().execute_with(|| {
+			assert_noop!(
+				NodeAuthorization::add_connections(
+					Origin::signed(15), PeerId(vec![1, 2, 3]), vec![test_node(5)]
+				),
+				Error::<Test>::PeerIdTooLong
+			);
+			assert_noop!(
+				NodeAuthorization::add_connections(
+					Origin::signed(15), test_node(15), vec![test_node(5)]
+				),
+				Error::<Test>::NotClaimed
+			);
+
+			assert_noop!(
+				NodeAuthorization::add_connections(
+					Origin::signed(15), test_node(20), vec![test_node(5)]
+				),
+				Error::<Test>::NotOwner
+			);
+
+			assert_ok!(
+				NodeAuthorization::add_connections(
+					Origin::signed(20),
+					test_node(20),
+					vec![test_node(15), test_node(5), test_node(25), test_node(20)]
+				)
+			);
+			assert_eq!(
+				AdditionalConnections::get(test_node(20)),
+				BTreeSet::from_iter(vec![test_node(5), test_node(15), test_node(25)])
+			);
+		});
+	}
+
+	#[test]
+	fn remove_connections_works() {
+		new_test_ext().execute_with(|| {
+			assert_noop!(
+				NodeAuthorization::remove_connections(
+					Origin::signed(15), PeerId(vec![1, 2, 3]), vec![test_node(5)]
+				),
+				Error::<Test>::PeerIdTooLong
+			);
+			assert_noop!(
+				NodeAuthorization::remove_connections(
+					Origin::signed(15), test_node(15), vec![test_node(5)]
+				),
+				Error::<Test>::NotClaimed
+			);
+
+			assert_noop!(
+				NodeAuthorization::remove_connections(
+					Origin::signed(15), test_node(20), vec![test_node(5)]
+				),
+				Error::<Test>::NotOwner
+			);
+
+			AdditionalConnections::insert(
+				test_node(20),
+				BTreeSet::from_iter(vec![test_node(5), test_node(15), test_node(25)])
+			);
+			assert_ok!(
+				NodeAuthorization::remove_connections(
+					Origin::signed(20),
+					test_node(20),
+					vec![test_node(15), test_node(5)]
+				)
+			);
+			assert_eq!(
+				AdditionalConnections::get(test_node(20)),
+				BTreeSet::from_iter(vec![test_node(25)])
+			);
+		});
+	}
+
+	#[test]
+	fn get_authorized_nodes_works() {
+		new_test_ext().execute_with(|| {
+			AdditionalConnections::insert(
+				test_node(20),
+				BTreeSet::from_iter(vec![test_node(5), test_node(15), test_node(25)])
+			);
+
+			let mut authorized_nodes = Module::<Test>::get_authorized_nodes(&test_node(20));
+			authorized_nodes.sort();
+			assert_eq!(
+				authorized_nodes,
+				vec![test_node(5), test_node(10), test_node(15), test_node(25), test_node(30)]
+			);
+		});
+	}
+}

substrate/primitives/core/src/lib.rs

@@ -32,6 +32,7 @@ macro_rules! map {
 	);
 }
 
+use sp_runtime_interface::pass_by::{PassByEnum, PassByInner};
 use sp_std::prelude::*;
 use sp_std::ops::Deref;
 #[cfg(feature = "std")]
@@ -176,6 +177,18 @@ impl sp_std::ops::Deref for OpaqueMetadata {
 	}
 }
 
+/// Simple blob to hold a `PeerId` without committing to its format.
+#[derive(Default, Clone, Eq, PartialEq, Ord, PartialOrd, Encode, Decode, RuntimeDebug, PassByInner)]
+#[cfg_attr(feature = "std", derive(Serialize, Deserialize))]
+pub struct OpaquePeerId(pub Vec<u8>);
+
+impl OpaquePeerId {
+	/// Create new `OpaquePeerId`
+	pub fn new(vec: Vec<u8>) -> Self {
+		OpaquePeerId(vec)
+	}
+}
+
 /// Something that is either a native or an encoded value.
 #[cfg(feature = "std")]
 pub enum NativeOrEncoded<R> {
@@ -257,7 +270,7 @@ pub trait TypeId {
 /// A log level matching the one from `log` crate.
 ///
 /// Used internally by `sp_io::log` method.
-#[derive(Encode, Decode, sp_runtime_interface::pass_by::PassByEnum, Copy, Clone)]
+#[derive(Encode, Decode, PassByEnum, Copy, Clone)]
 pub enum LogLevel {
 	/// `Error` log level.
 	Error = 1,

substrate/primitives/core/src/offchain/mod.rs

@@ -19,7 +19,7 @@
 
 use codec::{Encode, Decode};
 use sp_std::{prelude::{Vec, Box}, convert::TryFrom};
-use crate::RuntimeDebug;
+use crate::{OpaquePeerId, RuntimeDebug};
 use sp_runtime_interface::pass_by::{PassByCodec, PassByInner, PassByEnum};
 
 pub use crate::crypto::KeyTypeId;
@@ -184,23 +184,12 @@ impl TryFrom<u32> for HttpRequestStatus {
 #[derive(Clone, Eq, PartialEq, Encode, Decode, RuntimeDebug, PassByCodec)]
 #[cfg_attr(feature = "std", derive(Default))]
 pub struct OpaqueNetworkState {
-	/// PeerId of the local node.
+	/// PeerId of the local node in SCALE encoded.
 	pub peer_id: OpaquePeerId,
 	/// List of addresses the node knows it can be reached as.
 	pub external_addresses: Vec<OpaqueMultiaddr>,
 }
 
-/// Simple blob to hold a `PeerId` without committing to its format.
-#[derive(Default, Clone, Eq, PartialEq, Encode, Decode, RuntimeDebug, PassByInner)]
-pub struct OpaquePeerId(pub Vec<u8>);
-
-impl OpaquePeerId {
-	/// Create new `OpaquePeerId`
-	pub fn new(vec: Vec<u8>) -> Self {
-		OpaquePeerId(vec)
-	}
-}
-
 /// Simple blob to hold a `Multiaddr` without committing to its format.
 #[derive(Clone, Eq, PartialEq, Encode, Decode, RuntimeDebug, PassByInner)]
 pub struct OpaqueMultiaddr(pub Vec<u8>);
@@ -277,6 +266,8 @@ pub enum Capability {
 	OffchainWorkerDbRead = 32,
 	/// Access to offchain worker DB (writes).
 	OffchainWorkerDbWrite = 64,
+	/// Manage the authorized nodes
+	NodeAuthorization = 128,
 }
 
 /// A set of capabilities
@@ -495,6 +486,18 @@ pub trait Externalities: Send {
 		buffer: &mut [u8],
 		deadline: Option<Timestamp>
 	) -> Result<usize, HttpError>;
+
+	/// Set the authorized nodes from runtime.
+	///
+	/// In a permissioned network, the connections between nodes need to reach a
+	/// consensus between participants.
+	///
+	/// - `nodes`: a set of nodes which are allowed to connect for the local node.
+	/// each one is identified with an `OpaquePeerId`, here it just use plain bytes
+	/// without any encoding. Invalid `OpaquePeerId`s are silently ignored.
+	/// - `authorized_only`: if true, only the authorized nodes are allowed to connect,
+	/// otherwise unauthorized nodes can also be connected through other mechanism.
+	fn set_authorized_nodes(&mut self, nodes: Vec<OpaquePeerId>, authorized_only: bool);
 }
 
 impl<T: Externalities + ?Sized> Externalities for Box<T> {
@@ -573,6 +576,10 @@ impl<T: Externalities + ?Sized> Externalities for Box<T> {
 	) -> Result<usize, HttpError> {
 		(&mut **self).http_response_read_body(request_id, buffer, deadline)
 	}
+
+	fn set_authorized_nodes(&mut self, nodes: Vec<OpaquePeerId>, authorized_only: bool) {
+		(&mut **self).set_authorized_nodes(nodes, authorized_only)
+	}
 }
 
 /// An `OffchainExternalities` implementation with limited capabilities.
@@ -691,6 +698,11 @@ impl<T: Externalities> Externalities for LimitedExternalities<T> {
 		self.check(Capability::Http, "http_response_read_body");
 		self.externalities.http_response_read_body(request_id, buffer, deadline)
 	}
+
+	fn set_authorized_nodes(&mut self, nodes: Vec<OpaquePeerId>, authorized_only: bool) {
+		self.check(Capability::NodeAuthorization, "set_authorized_nodes");
+		self.externalities.set_authorized_nodes(nodes, authorized_only)
+	}
 }
 
 #[cfg(feature = "std")]

substrate/primitives/core/src/offchain/testing.rs

@@ -24,6 +24,7 @@ use std::{
 	collections::{BTreeMap, VecDeque},
 	sync::Arc,
 };
+use crate::OpaquePeerId;
 use crate::offchain::{
 	self,
 	storage::{InMemOffchainStorage, OffchainOverlayedChange, OffchainOverlayedChanges},
@@ -375,6 +376,10 @@ impl offchain::Externalities for TestOffchainExt {
 			Err(HttpError::IoError)
 		}
 	}
+
+	fn set_authorized_nodes(&mut self, _nodes: Vec<OpaquePeerId>, _authorized_only: bool) {
+		unimplemented!()
+	}
 }
 
 /// The internal state of the fake transaction pool.

substrate/primitives/io/src/lib.rs

@@ -42,7 +42,7 @@ use sp_core::{
 };
 
 use sp_core::{
-	crypto::KeyTypeId, ed25519, sr25519, ecdsa, H256, LogLevel,
+	OpaquePeerId, crypto::KeyTypeId, ed25519, sr25519, ecdsa, H256, LogLevel,
 	offchain::{
 		Timestamp, HttpRequestId, HttpRequestStatus, HttpError, StorageKind, OpaqueNetworkState,
 	},
@@ -960,6 +960,13 @@ pub trait Offchain {
 			.http_response_read_body(request_id, buffer, deadline)
 			.map(|r| r as u32)
 	}
+
+	/// Set the authorized nodes and authorized_only flag.
+	fn set_authorized_nodes(&mut self, nodes: Vec<OpaquePeerId>, authorized_only: bool) {
+		self.extension::<OffchainExt>()
+			.expect("set_authorized_nodes can be called only in the offchain worker context")
+			.set_authorized_nodes(nodes, authorized_only)
+	}
 }
 
 /// Wasm only interface that provides functions for calling into the allocator.