core/authority-discovery: Enable authorities to discover each other

Cargo.toml

@@ -63,6 +63,7 @@ members = [
 	"core/utils/fork-tree",
 	"core/utils/wasm-builder",
 	"core/utils/wasm-builder-runner",
+	"core/authority-discovery",
 	"srml/support",
 	"srml/support/procedural",
 	"srml/support/procedural/tools",

core/authority-discovery/Cargo.toml

@@ -0,0 +1,32 @@
+[package]
+name = "substrate-authority-discovery"
+version = "2.0.0"
+authors = ["Parity Technologies <admin@parity.io>"]
+edition = "2018"
+build = "build.rs"
+
+[build-dependencies]
+prost-build = "0.5"
+
+[dependencies]
+authority-discovery-primitives = { package = "substrate-authority-discovery-primitives", path = "./primitives", default-features = false }
+bytes = "0.4"
+client = { package = "substrate-client", path = "../../core/client" }
+codec = { package = "parity-scale-codec", default-features = false, version = "1.0.3" }
+derive_more = "0.14.0"
+futures = "0.1"
+keystore = { package = "substrate-keystore", path = "../../core/keystore" }
+libp2p = { version = "0.12.0", default-features = false, features = ["secp256k1", "libp2p-websocket"] }
+log = "0.4"
+network = { package = "substrate-network", path = "../../core/network" }
+primitives = { package = "substrate-primitives", path = "../primitives" }
+prost = "0.5"
+serde_json = "1.0"
+sr-primitives = { path = "../../core/sr-primitives" }
+tokio-timer = "0.2"
+
+[dev-dependencies]
+parking_lot = { version = "0.9.0" }
+peerset = { package = "substrate-peerset", path = "../../core/peerset" }
+test-client = { package = "substrate-test-runtime-client", path = "../../core/test-runtime/client" }
+tokio = { version = "0.1"}

core/authority-discovery/build.rs

@@ -0,0 +1,3 @@
+fn main() {
+	prost_build::compile_protos(&["src/schema/dht.proto"], &["src/schema"]).unwrap();
+}

core/authority-discovery/primitives/src/lib.rs

@@ -19,31 +19,31 @@
 #![cfg_attr(not(feature = "std"), no_std)]
 
 use client::decl_runtime_apis;
-use codec::Codec;
 use rstd::vec::Vec;
 
+#[derive(codec::Encode, codec::Decode, Eq, PartialEq, Clone)]
+#[cfg_attr(feature = "std", derive(Debug, Hash))]
+pub struct Signature(pub Vec<u8>);
+#[derive(codec::Encode, codec::Decode, Eq, PartialEq, Clone)]
+#[cfg_attr(feature = "std", derive(Debug, Hash))]
+pub struct AuthorityId(pub Vec<u8>);
+
 decl_runtime_apis! {
 	/// The authority discovery api.
 	///
 	/// This api is used by the `core/authority-discovery` module to retrieve our
 	/// own authority identifier, to retrieve identifiers of the current authority
 	/// set, as well as sign and verify Kademlia Dht external address payloads
 	/// from and to other authorities.
-	pub trait AuthorityDiscoveryApi<AuthorityId: Codec> {
-		/// Returns own authority identifier iff it is part of the current authority
-		/// set, otherwise this function returns None. The restriction might be
-		/// softened in the future in case a consumer needs to learn own authority
-		/// identifier.
-		fn authority_id() -> Option<AuthorityId>;
-
+	pub trait AuthorityDiscoveryApi {
 		/// Retrieve authority identifiers of the current authority set.
 		fn authorities() -> Vec<AuthorityId>;
 
 		/// Sign the given payload with the private key corresponding to the given authority id.
-		fn sign(payload: Vec<u8>, authority_id: AuthorityId) -> Option<Vec<u8>>;
+		fn sign(payload: &Vec<u8>) -> Option<(Signature, AuthorityId)>;
 
 		/// Verify the given signature for the given payload with the given
 		/// authority identifier.
-		fn verify(payload: Vec<u8>, signature: Vec<u8>, authority_id: AuthorityId) -> bool;
+		fn verify(payload: &Vec<u8>, signature: &Signature, authority_id: &AuthorityId) -> bool;
 	}
 }

core/authority-discovery/src/error.rs

@@ -0,0 +1,47 @@
+// Copyright 2019 Parity Technologies (UK) Ltd.
+// This file is part of Substrate.
+
+// Substrate is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Substrate is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Substrate.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Authority discovery errors.
+
+/// AuthorityDiscovery Result.
+pub type Result<T> = std::result::Result<T, Error>;
+
+/// Error type for the authority discovery module.
+#[derive(Debug, derive_more::Display, derive_more::From)]
+pub enum Error {
+	/// Failed to verify a dht payload with the given signature.
+	VerifyingDhtPayload,
+	/// Failed to hash the authority id to be used as a dht key.
+	HashingAuthorityId(libp2p::core::multiaddr::multihash::EncodeError),
+	/// Failed calling into the Substrate runtime.
+	CallingRuntime(client::error::Error),
+	/// Failed signing the dht payload via the Substrate runtime.
+	SigningDhtPayload,
+	/// From the Dht we only get the hashed authority id. In order to retrieve the actual authority id and to ensure it
+	/// is actually an authority, we match the hash against the hash of the authority id of all other authorities. This
+	/// error is the result of the above failing.
+	MatchingHashedAuthorityIdWithAuthorityId,
+	/// Failed to set the authority discovery peerset priority group in the peerset module.
+	SettingPeersetPriorityGroup(String),
+	/// Failed to encode a dht payload.
+	Encoding(prost::EncodeError),
+	/// Failed to decode a dht payload.
+	Decoding(prost::DecodeError),
+	/// Failed to parse a libp2p multi address.
+	ParsingMultiaddress(libp2p::core::multiaddr::Error),
+	/// Tokio timer error.
+	PollingTokioTimer(tokio_timer::Error)
+}