Merge branch 'master' into ci-rustfmt

Cargo.toml

@@ -29,4 +29,5 @@ members = [
 	"beacon_node/beacon_chain/test_harness",
 	"protos",
 	"validator_client",
+	"account_manager",
 ]

account_manager/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "account_manager"
+version = "0.0.1"
+authors = ["Luke Anderson <luke@sigmaprime.io>"]
+edition = "2018"
+
+[dependencies]
+bls = { path = "../eth2/utils/bls" }
+clap = "2.32.0"
+slog = "^2.2.3"
+slog-term = "^2.4.0"
+slog-async = "^2.3.0"
+validator_client = { path = "../validator_client" }

account_manager/README.md

@@ -0,0 +1,24 @@
+# Lighthouse Accounts Manager
+
+The accounts manager (AM) is a stand-alone binary which allows
+users to generate and manage the cryptographic keys necessary to
+interact with Ethereum Serenity.
+
+## Roles
+
+The AM is responsible for the following tasks:
+- Generation of cryptographic key pairs
+  - Must acquire sufficient entropy to ensure keys are generated securely (TBD)
+- Secure storage of private keys
+  - Keys must be encrypted while at rest on the disk (TBD)
+  - The format is compatible with the validator client
+- Produces messages and transactions necessary to initiate
+staking on Ethereum 1.x (TPD)
+
+
+## Implementation
+
+The AM is not a service, and does not run continuously, nor does it
+interact with any running services.
+It is intended to be executed separately from other Lighthouse binaries
+and produce files which can be consumed by them.

account_manager/src/main.rs

@@ -0,0 +1,58 @@
+use bls::Keypair;
+use clap::{App, Arg, SubCommand};
+use slog::{debug, info, o, Drain};
+use std::path::PathBuf;
+use validator_client::Config as ValidatorClientConfig;
+
+fn main() {
+    // Logging
+    let decorator = slog_term::TermDecorator::new().build();
+    let drain = slog_term::CompactFormat::new(decorator).build().fuse();
+    let drain = slog_async::Async::new(drain).build().fuse();
+    let log = slog::Logger::root(drain, o!());
+
+    // CLI
+    let matches = App::new("Lighthouse Accounts Manager")
+        .version("0.0.1")
+        .author("Sigma Prime <contact@sigmaprime.io>")
+        .about("Eth 2.0 Accounts Manager")
+        .arg(
+            Arg::with_name("datadir")
+                .long("datadir")
+                .value_name("DIR")
+                .help("Data directory for keys and databases.")
+                .takes_value(true),
+        )
+        .subcommand(
+            SubCommand::with_name("generate")
+                .about("Generates a new validator private key")
+                .version("0.0.1")
+                .author("Sigma Prime <contact@sigmaprime.io>"),
+        )
+        .get_matches();
+
+    let config = ValidatorClientConfig::parse_args(&matches, &log)
+        .expect("Unable to build a configuration for the account manager.");
+
+    // Log configuration
+    info!(log, "";
+          "data_dir" => &config.data_dir.to_str());
+
+    match matches.subcommand() {
+        ("generate", Some(_gen_m)) => {
+            let keypair = Keypair::random();
+            let key_path: PathBuf = config
+                .save_key(&keypair)
+                .expect("Unable to save newly generated private key.");
+            debug!(
+                log,
+                "Keypair generated {:?}, saved to: {:?}",
+                keypair.identifier(),
+                key_path.to_string_lossy()
+            );
+        }
+        _ => panic!(
+            "The account manager must be run with a subcommand. See help for more information."
+        ),
+    }
+}

beacon_node/eth2-libp2p/Cargo.toml

@@ -6,7 +6,7 @@ edition = "2018"
 
 [dependencies]
 # SigP repository until PR is merged
-libp2p =  { git = "https://github.com/SigP/rust-libp2p", branch = "gossipsub" }
+libp2p =  { git = "https://github.com/SigP/rust-libp2p", rev = "987fec350b5c2eb55e5f0139615adab49ce493ff" }
 types = { path =  "../../eth2/types" }
 ssz = { path = "../../eth2/utils/ssz" }
 ssz_derive = { path = "../../eth2/utils/ssz_derive" }

beacon_node/eth2-libp2p/src/behaviour.rs

@@ -1,11 +1,18 @@
 use crate::rpc::{RPCEvent, RPCMessage, Rpc};
+use crate::NetworkConfig;
 use futures::prelude::*;
 use libp2p::{
-    core::swarm::{NetworkBehaviourAction, NetworkBehaviourEventProcess},
-    gossipsub::{Gossipsub, GossipsubConfig, GossipsubEvent},
+    core::{
+        swarm::{NetworkBehaviourAction, NetworkBehaviourEventProcess},
+        PublicKey,
+    },
+    gossipsub::{Gossipsub, GossipsubEvent},
+    identify::{protocol::IdentifyInfo, Identify, IdentifyEvent},
+    ping::{Ping, PingEvent},
     tokio_io::{AsyncRead, AsyncWrite},
     NetworkBehaviour, PeerId,
 };
+use slog::{debug, o};
 use types::Topic;
 
 /// Builds the network behaviour for the libp2p Swarm.
@@ -13,12 +20,22 @@ use types::Topic;
 #[derive(NetworkBehaviour)]
 #[behaviour(out_event = "BehaviourEvent", poll_method = "poll")]
 pub struct Behaviour<TSubstream: AsyncRead + AsyncWrite> {
+    /// The routing pub-sub mechanism for eth2.
     gossipsub: Gossipsub<TSubstream>,
     // TODO: Add Kademlia for peer discovery
     /// The events generated by this behaviour to be consumed in the swarm poll.
     serenity_rpc: Rpc<TSubstream>,
+    /// Allows discovery of IP addresses for peers on the network.
+    identify: Identify<TSubstream>,
+    /// Keep regular connection to peers and disconnect if absent.
+    // TODO: Keepalive, likely remove this later.
+    // TODO: Make the ping time customizeable.
+    ping: Ping<TSubstream>,
     #[behaviour(ignore)]
     events: Vec<BehaviourEvent>,
+    /// Logger for behaviour actions.
+    #[behaviour(ignore)]
+    log: slog::Logger,
 }
 
 // Implement the NetworkBehaviourEventProcess trait so that we can derive NetworkBehaviour for Behaviour
@@ -53,12 +70,54 @@ impl<TSubstream: AsyncRead + AsyncWrite> NetworkBehaviourEventProcess<RPCMessage
     }
 }
 
+impl<TSubstream: AsyncRead + AsyncWrite> NetworkBehaviourEventProcess<IdentifyEvent>
+    for Behaviour<TSubstream>
+{
+    fn inject_event(&mut self, event: IdentifyEvent) {
+        match event {
+            IdentifyEvent::Identified {
+                peer_id, mut info, ..
+            } => {
+                if info.listen_addrs.len() > 20 {
+                    debug!(
+                        self.log,
+                        "More than 20 peers have been identified, truncating"
+                    );
+                    info.listen_addrs.truncate(20);
+                }
+                self.events.push(BehaviourEvent::Identified(peer_id, info));
+            }
+            IdentifyEvent::Error { .. } => {}
+            IdentifyEvent::SendBack { .. } => {}
+        }
+    }
+}
+
+impl<TSubstream: AsyncRead + AsyncWrite> NetworkBehaviourEventProcess<PingEvent>
+    for Behaviour<TSubstream>
+{
+    fn inject_event(&mut self, _event: PingEvent) {
+        // not interested in ping responses at the moment.
+    }
+}
+
 impl<TSubstream: AsyncRead + AsyncWrite> Behaviour<TSubstream> {
-    pub fn new(local_peer_id: PeerId, gs_config: GossipsubConfig, log: &slog::Logger) -> Self {
+    pub fn new(local_public_key: PublicKey, net_conf: &NetworkConfig, log: &slog::Logger) -> Self {
+        let local_peer_id = local_public_key.clone().into_peer_id();
+        let identify_config = net_conf.identify_config.clone();
+        let behaviour_log = log.new(o!());
+
         Behaviour {
-            gossipsub: Gossipsub::new(local_peer_id, gs_config),
+            gossipsub: Gossipsub::new(local_peer_id, net_conf.gs_config.clone()),
             serenity_rpc: Rpc::new(log),
+            identify: Identify::new(
+                identify_config.version,
+                identify_config.user_agent,
+                local_public_key,
+            ),
+            ping: Ping::new(),
             events: Vec::new(),
+            log: behaviour_log,
         }
     }
 
@@ -91,6 +150,7 @@ impl<TSubstream: AsyncRead + AsyncWrite> Behaviour<TSubstream> {
 pub enum BehaviourEvent {
     RPC(PeerId, RPCEvent),
     PeerDialed(PeerId),
+    Identified(PeerId, IdentifyInfo),
     // TODO: This is a stub at the moment
     Message(String),
 }

beacon_node/eth2-libp2p/src/config.rs

@@ -1,11 +1,9 @@
 use crate::Multiaddr;
 use libp2p::gossipsub::{GossipsubConfig, GossipsubConfigBuilder};
-use libp2p::secio;
-use std::fmt;
 
-#[derive(Clone)]
+#[derive(Clone, Debug)]
 /// Network configuration for lighthouse.
-pub struct NetworkConfig {
+pub struct Config {
     //TODO: stubbing networking initial params, change in the future
     /// IP address to listen on.
     pub listen_addresses: Vec<Multiaddr>,
@@ -13,47 +11,58 @@ pub struct NetworkConfig {
     pub listen_port: u16,
     /// Gossipsub configuration parameters.
     pub gs_config: GossipsubConfig,
+    /// Configuration parameters for node identification protocol.
+    pub identify_config: IdentifyConfig,
     /// List of nodes to initially connect to.
     pub boot_nodes: Vec<Multiaddr>,
-    /// Peer key related to this nodes PeerId.
-    pub local_private_key: secio::SecioKeyPair,
     /// Client version
     pub client_version: String,
     /// List of topics to subscribe to as strings
     pub topics: Vec<String>,
 }
 
-impl Default for NetworkConfig {
+impl Default for Config {
     /// Generate a default network configuration.
     fn default() -> Self {
-        // TODO: Currently using secp256k1 key pairs. Wire protocol specifies RSA. Waiting for this
-        // PR to be merged to generate RSA keys: https://github.com/briansmith/ring/pull/733
-
-        NetworkConfig {
+        Config {
             listen_addresses: vec!["/ip4/127.0.0.1/tcp/9000"
                 .parse()
                 .expect("is a correct multi-address")],
             listen_port: 9000,
-            gs_config: GossipsubConfigBuilder::new().build(),
+            gs_config: GossipsubConfigBuilder::new()
+                .max_gossip_size(4_000_000)
+                .build(),
+            identify_config: IdentifyConfig::default(),
             boot_nodes: Vec::new(),
-            local_private_key: secio::SecioKeyPair::secp256k1_generated().unwrap(),
             client_version: version::version(),
             topics: vec![String::from("beacon_chain")],
         }
     }
 }
 
-impl NetworkConfig {
+impl Config {
     pub fn new(boot_nodes: Vec<Multiaddr>) -> Self {
-        let mut conf = NetworkConfig::default();
+        let mut conf = Config::default();
         conf.boot_nodes = boot_nodes;
 
         conf
     }
 }
 
-impl fmt::Debug for NetworkConfig {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        write!(f, "NetworkConfig: listen_addresses: {:?}, listen_port: {:?}, gs_config: {:?}, boot_nodes: {:?}, local_private_key: <Secio-PubKey {:?}>, client_version: {:?}", self.listen_addresses, self.listen_port, self.gs_config, self.boot_nodes, self.local_private_key.to_public_key(), self.client_version)
+/// The configuration parameters for the Identify protocol
+#[derive(Debug, Clone)]
+pub struct IdentifyConfig {
+    /// The protocol version to listen on.
+    pub version: String,
+    /// The client's name and version for identification.
+    pub user_agent: String,
+}
+
+impl Default for IdentifyConfig {
+    fn default() -> Self {
+        Self {
+            version: "/eth/serenity/1.0".to_string(),
+            user_agent: version::version(),
+        }
     }
 }

beacon_node/eth2-libp2p/src/lib.rs

@@ -3,16 +3,16 @@
 ///
 /// This crate builds and manages the libp2p services required by the beacon node.
 pub mod behaviour;
+mod config;
 pub mod error;
-mod network_config;
 pub mod rpc;
 mod service;
 
+pub use config::Config as NetworkConfig;
 pub use libp2p::{
     gossipsub::{GossipsubConfig, GossipsubConfigBuilder},
     PeerId,
 };
-pub use network_config::NetworkConfig;
 pub use rpc::{HelloMessage, RPCEvent};
 pub use service::Libp2pEvent;
 pub use service::Service;

beacon_node/eth2-libp2p/src/rpc/protocol.rs

@@ -1,4 +1,4 @@
-use super::methods::{HelloMessage, RPCMethod, RPCRequest, RPCResponse};
+use super::methods::*;
 use libp2p::core::{upgrade, InboundUpgrade, OutboundUpgrade, UpgradeInfo};
 use ssz::{ssz_encode, Decodable, Encodable, SszStream};
 use std::io;
@@ -6,7 +6,7 @@ use std::iter;
 use tokio::io::{AsyncRead, AsyncWrite};
 
 /// The maximum bytes that can be sent across the RPC.
-const MAX_READ_SIZE: usize = 2048;
+const MAX_READ_SIZE: usize = 4_194_304; // 4M
 
 /// Implementation of the `ConnectionUpgrade` for the rpc protocol.
 
@@ -60,10 +60,13 @@ where
 {
     type Output = RPCEvent;
     type Error = DecodeError;
-    type Future =
-        upgrade::ReadOneThen<TSocket, (), fn(Vec<u8>, ()) -> Result<RPCEvent, DecodeError>>;
+    type Future = upgrade::ReadOneThen<
+        upgrade::Negotiated<TSocket>,
+        (),
+        fn(Vec<u8>, ()) -> Result<RPCEvent, DecodeError>,
+    >;
 
-    fn upgrade_inbound(self, socket: TSocket, _: Self::Info) -> Self::Future {
+    fn upgrade_inbound(self, socket: upgrade::Negotiated<TSocket>, _: Self::Info) -> Self::Future {
         upgrade::read_one_then(socket, MAX_READ_SIZE, (), |packet, ()| Ok(decode(packet)?))
     }
 }
@@ -81,7 +84,31 @@ fn decode(packet: Vec<u8>) -> Result<RPCEvent, DecodeError> {
                 let (hello_body, _index) = HelloMessage::ssz_decode(&packet, index)?;
                 RPCRequest::Hello(hello_body)
             }
-            RPCMethod::Unknown | _ => return Err(DecodeError::UnknownRPCMethod),
+            RPCMethod::Goodbye => {
+                let (goodbye_code, _index) = u64::ssz_decode(&packet, index)?;
+                RPCRequest::Goodbye(goodbye_code)
+            }
+            RPCMethod::BeaconBlockRoots => {
+                let (block_roots_request, _index) =
+                    BeaconBlockRootsRequest::ssz_decode(&packet, index)?;
+                RPCRequest::BeaconBlockRoots(block_roots_request)
+            }
+            RPCMethod::BeaconBlockHeaders => {
+                let (block_headers_request, _index) =
+                    BeaconBlockHeadersRequest::ssz_decode(&packet, index)?;
+                RPCRequest::BeaconBlockHeaders(block_headers_request)
+            }
+            RPCMethod::BeaconBlockBodies => {
+                let (block_bodies_request, _index) =
+                    BeaconBlockBodiesRequest::ssz_decode(&packet, index)?;
+                RPCRequest::BeaconBlockBodies(block_bodies_request)
+            }
+            RPCMethod::BeaconChainState => {
+                let (chain_state_request, _index) =
+                    BeaconChainStateRequest::ssz_decode(&packet, index)?;
+                RPCRequest::BeaconChainState(chain_state_request)
+            }
+            RPCMethod::Unknown => return Err(DecodeError::UnknownRPCMethod),
         };
 
         Ok(RPCEvent::Request {
@@ -97,7 +124,24 @@ fn decode(packet: Vec<u8>) -> Result<RPCEvent, DecodeError> {
                 let (body, _index) = HelloMessage::ssz_decode(&packet, index)?;
                 RPCResponse::Hello(body)
             }
-            RPCMethod::Unknown | _ => return Err(DecodeError::UnknownRPCMethod),
+            RPCMethod::Goodbye => unreachable!("Should never receive a goodbye response"),
+            RPCMethod::BeaconBlockRoots => {
+                let (body, _index) = BeaconBlockRootsResponse::ssz_decode(&packet, index)?;
+                RPCResponse::BeaconBlockRoots(body)
+            }
+            RPCMethod::BeaconBlockHeaders => {
+                let (body, _index) = BeaconBlockHeadersResponse::ssz_decode(&packet, index)?;
+                RPCResponse::BeaconBlockHeaders(body)
+            }
+            RPCMethod::BeaconBlockBodies => {
+                let (body, _index) = BeaconBlockBodiesResponse::ssz_decode(&packet, index)?;
+                RPCResponse::BeaconBlockBodies(body)
+            }
+            RPCMethod::BeaconChainState => {
+                let (body, _index) = BeaconChainStateResponse::ssz_decode(&packet, index)?;
+                RPCResponse::BeaconChainState(body)
+            }
+            RPCMethod::Unknown => return Err(DecodeError::UnknownRPCMethod),
         };
         Ok(RPCEvent::Response {
             id,
@@ -113,10 +157,10 @@ where
 {
     type Output = ();
     type Error = io::Error;
-    type Future = upgrade::WriteOne<TSocket>;
+    type Future = upgrade::WriteOne<upgrade::Negotiated<TSocket>>;
 
     #[inline]
-    fn upgrade_outbound(self, socket: TSocket, _: Self::Info) -> Self::Future {
+    fn upgrade_outbound(self, socket: upgrade::Negotiated<TSocket>, _: Self::Info) -> Self::Future {
         let bytes = ssz_encode(&self);
         upgrade::write_one(socket, bytes)
     }
@@ -137,7 +181,21 @@ impl Encodable for RPCEvent {
                     RPCRequest::Hello(body) => {
                         s.append(body);
                     }
-                    _ => {}
+                    RPCRequest::Goodbye(body) => {
+                        s.append(body);
+                    }
+                    RPCRequest::BeaconBlockRoots(body) => {
+                        s.append(body);
+                    }
+                    RPCRequest::BeaconBlockHeaders(body) => {
+                        s.append(body);
+                    }
+                    RPCRequest::BeaconBlockBodies(body) => {
+                        s.append(body);
+                    }
+                    RPCRequest::BeaconChainState(body) => {
+                        s.append(body);
+                    }
                 }
             }
             RPCEvent::Response {
@@ -152,7 +210,18 @@ impl Encodable for RPCEvent {
                     RPCResponse::Hello(response) => {
                         s.append(response);
                     }
-                    _ => {}
+                    RPCResponse::BeaconBlockRoots(response) => {
+                        s.append(response);
+                    }
+                    RPCResponse::BeaconBlockHeaders(response) => {
+                        s.append(response);
+                    }
+                    RPCResponse::BeaconBlockBodies(response) => {
+                        s.append(response);
+                    }
+                    RPCResponse::BeaconChainState(response) => {
+                        s.append(response);
+                    }
                 }
             }
         }

beacon_node/eth2-libp2p/src/service.rs

@@ -6,13 +6,14 @@ use crate::NetworkConfig;
 use futures::prelude::*;
 use futures::Stream;
 use libp2p::core::{
+    identity,
     muxing::StreamMuxerBox,
     nodes::Substream,
     transport::boxed::Boxed,
     upgrade::{InboundUpgradeExt, OutboundUpgradeExt},
 };
-use libp2p::{core, secio, Transport};
-use libp2p::{PeerId, Swarm};
+use libp2p::identify::protocol::IdentifyInfo;
+use libp2p::{core, secio, PeerId, Swarm, Transport};
 use slog::{debug, info, trace, warn};
 use std::io::{Error, ErrorKind};
 use std::time::Duration;
@@ -33,15 +34,20 @@ impl Service {
     pub fn new(config: NetworkConfig, log: slog::Logger) -> error::Result<Self> {
         debug!(log, "Libp2p Service starting");
 
-        let local_private_key = config.local_private_key;
-        let local_peer_id = local_private_key.to_peer_id();
+        // TODO: Currently using secp256k1 key pairs. Wire protocol specifies RSA. Waiting for this
+        // PR to be merged to generate RSA keys: https://github.com/briansmith/ring/pull/733
+        // TODO: Save and recover node key from disk
+        let local_private_key = identity::Keypair::generate_secp256k1();
+
+        let local_public_key = local_private_key.public();
+        let local_peer_id = PeerId::from(local_private_key.public());
         info!(log, "Local peer id: {:?}", local_peer_id);
 
         let mut swarm = {
             // Set up the transport
             let transport = build_transport(local_private_key);
             // Set up gossipsub routing
-            let behaviour = Behaviour::new(local_peer_id.clone(), config.gs_config, &log);
+            let behaviour = Behaviour::new(local_public_key.clone(), &config, &log);
             // Set up Topology
             let topology = local_peer_id.clone();
             Swarm::new(transport, behaviour, topology)
@@ -99,17 +105,23 @@ impl Stream for Service {
             // TODO: Currently only gossipsub events passed here.
             // Build a type for more generic events
             match self.swarm.poll() {
-                Ok(Async::Ready(Some(BehaviourEvent::Message(m)))) => {
+                //Behaviour events
+                Ok(Async::Ready(Some(event))) => match event {
                     // TODO: Stub here for debugging
-                    debug!(self.log, "Message received: {}", m);
-                    return Ok(Async::Ready(Some(Libp2pEvent::Message(m))));
-                }
-                Ok(Async::Ready(Some(BehaviourEvent::RPC(peer_id, event)))) => {
-                    return Ok(Async::Ready(Some(Libp2pEvent::RPC(peer_id, event))));
-                }
-                Ok(Async::Ready(Some(BehaviourEvent::PeerDialed(peer_id)))) => {
-                    return Ok(Async::Ready(Some(Libp2pEvent::PeerDialed(peer_id))));
-                }
+                    BehaviourEvent::Message(m) => {
+                        debug!(self.log, "Message received: {}", m);
+                        return Ok(Async::Ready(Some(Libp2pEvent::Message(m))));
+                    }
+                    BehaviourEvent::RPC(peer_id, event) => {
+                        return Ok(Async::Ready(Some(Libp2pEvent::RPC(peer_id, event))));
+                    }
+                    BehaviourEvent::PeerDialed(peer_id) => {
+                        return Ok(Async::Ready(Some(Libp2pEvent::PeerDialed(peer_id))));
+                    }
+                    BehaviourEvent::Identified(peer_id, info) => {
+                        return Ok(Async::Ready(Some(Libp2pEvent::Identified(peer_id, info))));
+                    }
+                },
                 Ok(Async::Ready(None)) => unreachable!("Swarm stream shouldn't end"),
                 Ok(Async::NotReady) => break,
                 _ => break,
@@ -121,9 +133,7 @@ impl Stream for Service {
 
 /// The implementation supports TCP/IP, WebSockets over TCP/IP, secio as the encryption layer, and
 /// mplex or yamux as the multiplexing layer.
-fn build_transport(
-    local_private_key: secio::SecioKeyPair,
-) -> Boxed<(PeerId, StreamMuxerBox), Error> {
+fn build_transport(local_private_key: identity::Keypair) -> Boxed<(PeerId, StreamMuxerBox), Error> {
     // TODO: The Wire protocol currently doesn't specify encryption and this will need to be customised
     // in the future.
     let transport = libp2p::tcp::TcpConfig::new();
@@ -156,8 +166,12 @@ fn build_transport(
 
 /// Events that can be obtained from polling the Libp2p Service.
 pub enum Libp2pEvent {
-    // We have received an RPC event on the swarm
+    /// An RPC response request has been received on the swarm.
     RPC(PeerId, RPCEvent),
+    /// Initiated the connection to a new peer.
     PeerDialed(PeerId),
+    /// Received information about a peer on the network.
+    Identified(PeerId, IdentifyInfo),
+    // TODO: Pub-sub testing only.
     Message(String),
 }

beacon_node/network/src/service.rs

@@ -15,8 +15,8 @@ use tokio::runtime::TaskExecutor;
 
 /// Service that handles communication between internal services and the eth2_libp2p network service.
 pub struct Service {
-    //eth2_libp2p_service: Arc<Mutex<LibP2PService>>,
-    eth2_libp2p_exit: oneshot::Sender<()>,
+    //libp2p_service: Arc<Mutex<LibP2PService>>,
+    libp2p_exit: oneshot::Sender<()>,
     network_send: crossbeam_channel::Sender<NetworkMessage>,
     //message_handler: MessageHandler,
     //message_handler_send: Sender<HandlerMessage>,
@@ -40,20 +40,20 @@ impl Service {
             message_handler_log,
         )?;
 
-        // launch eth2_libp2p service
-        let eth2_libp2p_log = log.new(o!("Service" => "Libp2p"));
-        let eth2_libp2p_service = LibP2PService::new(config.clone(), eth2_libp2p_log)?;
+        // launch libp2p service
+        let libp2p_log = log.new(o!("Service" => "Libp2p"));
+        let libp2p_service = LibP2PService::new(config.clone(), libp2p_log)?;
 
-        // TODO: Spawn thread to handle eth2_libp2p messages and pass to message handler thread.
-        let eth2_libp2p_exit = spawn_service(
-            eth2_libp2p_service,
+        // TODO: Spawn thread to handle libp2p messages and pass to message handler thread.
+        let libp2p_exit = spawn_service(
+            libp2p_service,
             network_recv,
             message_handler_send,
             executor,
             log,
         )?;
         let network_service = Service {
-            eth2_libp2p_exit,
+            libp2p_exit,
             network_send: network_send.clone(),
         };
 
@@ -72,7 +72,7 @@ impl Service {
 }
 
 fn spawn_service(
-    eth2_libp2p_service: LibP2PService,
+    libp2p_service: LibP2PService,
     network_recv: crossbeam_channel::Receiver<NetworkMessage>,
     message_handler_send: crossbeam_channel::Sender<HandlerMessage>,
     executor: &TaskExecutor,
@@ -83,7 +83,7 @@ fn spawn_service(
     // spawn on the current executor
     executor.spawn(
         network_service(
-            eth2_libp2p_service,
+            libp2p_service,
             network_recv,
             message_handler_send,
             log.clone(),
@@ -100,7 +100,7 @@ fn spawn_service(
 }
 
 fn network_service(
-    mut eth2_libp2p_service: LibP2PService,
+    mut libp2p_service: LibP2PService,
     network_recv: crossbeam_channel::Receiver<NetworkMessage>,
     message_handler_send: crossbeam_channel::Sender<HandlerMessage>,
     log: slog::Logger,
@@ -108,28 +108,34 @@ fn network_service(
     futures::future::poll_fn(move || -> Result<_, eth2_libp2p::error::Error> {
         // poll the swarm
         loop {
-            match eth2_libp2p_service.poll() {
-                Ok(Async::Ready(Some(Libp2pEvent::RPC(peer_id, rpc_event)))) => {
-                    trace!(
-                        eth2_libp2p_service.log,
-                        "RPC Event: RPC message received: {:?}",
-                        rpc_event
-                    );
-                    message_handler_send
-                        .send(HandlerMessage::RPC(peer_id, rpc_event))
-                        .map_err(|_| "failed to send rpc to handler")?;
-                }
-                Ok(Async::Ready(Some(Libp2pEvent::PeerDialed(peer_id)))) => {
-                    debug!(eth2_libp2p_service.log, "Peer Dialed: {:?}", peer_id);
-                    message_handler_send
-                        .send(HandlerMessage::PeerDialed(peer_id))
-                        .map_err(|_| "failed to send rpc to handler")?;
-                }
-                Ok(Async::Ready(Some(Libp2pEvent::Message(m)))) => debug!(
-                    eth2_libp2p_service.log,
-                    "Network Service: Message received: {}", m
-                ),
-                _ => break,
+            match libp2p_service.poll() {
+                Ok(Async::Ready(Some(event))) => match event {
+                    Libp2pEvent::RPC(peer_id, rpc_event) => {
+                        trace!(log, "RPC Event: RPC message received: {:?}", rpc_event);
+                        message_handler_send
+                            .send(HandlerMessage::RPC(peer_id, rpc_event))
+                            .map_err(|_| "failed to send rpc to handler")?;
+                    }
+                    Libp2pEvent::PeerDialed(peer_id) => {
+                        debug!(log, "Peer Dialed: {:?}", peer_id);
+                        message_handler_send
+                            .send(HandlerMessage::PeerDialed(peer_id))
+                            .map_err(|_| "failed to send rpc to handler")?;
+                    }
+                    Libp2pEvent::Identified(peer_id, info) => {
+                        debug!(
+                            log,
+                            "We have identified peer: {:?} with {:?}", peer_id, info
+                        );
+                    }
+                    Libp2pEvent::Message(m) => debug!(
+                        libp2p_service.log,
+                        "Network Service: Message received: {}", m
+                    ),
+                },
+                Ok(Async::Ready(None)) => unreachable!("Stream never ends"),
+                Ok(Async::NotReady) => break,
+                Err(_) => break,
             }
         }
         // poll the network channel
@@ -143,7 +149,7 @@ fn network_service(
                             trace!(log, "Sending RPC Event: {:?}", rpc_event);
                             //TODO: Make swarm private
                             //TODO: Implement correct peer id topic message handling
-                            eth2_libp2p_service.swarm.send_rpc(peer_id, rpc_event);
+                            libp2p_service.swarm.send_rpc(peer_id, rpc_event);
                         }
                         OutgoingMessage::NotifierTest => {
                             debug!(log, "Received message from notifier");
@@ -165,7 +171,7 @@ fn network_service(
 /// Types of messages that the network service can receive.
 #[derive(Debug, Clone)]
 pub enum NetworkMessage {
-    /// Send a message to eth2_libp2p service.
+    /// Send a message to libp2p service.
     //TODO: Define typing for messages across the wire
     Send(PeerId, OutgoingMessage),
 }

eth2/state_processing/tests/tests.rs

@@ -15,12 +15,10 @@ pub struct TestDoc {
     pub title: String,
     pub summary: String,
     pub fork: String,
-    pub version: String,
     pub test_cases: Vec<TestCase>,
 }
 
 #[test]
-#[ignore]
 fn yaml() {
     use serde_yaml;
     use std::{fs::File, io::prelude::*, path::PathBuf};

eth2/types/Cargo.toml

@@ -10,6 +10,7 @@ boolean-bitfield = { path = "../utils/boolean-bitfield" }
 dirs = "1.0"
 ethereum-types = "0.5"
 hashing = { path = "../utils/hashing" }
+hex = "0.3"
 honey-badger-split =  { path = "../utils/honey-badger-split" }
 int_to_bytes = { path = "../utils/int_to_bytes" }
 log = "0.4"
@@ -24,7 +25,7 @@ ssz = { path = "../utils/ssz" }
 ssz_derive = { path = "../utils/ssz_derive" }
 swap_or_not_shuffle = { path = "../utils/swap_or_not_shuffle" }
 test_random_derive = { path = "../utils/test_random_derive" }
-libp2p =  { git = "https://github.com/SigP/rust-libp2p", branch = "gossipsub" }
+libp2p =  { git = "https://github.com/SigP/rust-libp2p", rev = "987fec350b5c2eb55e5f0139615adab49ce493ff" }
 
 [dev-dependencies]
 env_logger = "0.6.0"

eth2/types/src/chain_spec.rs

@@ -2,6 +2,7 @@ use crate::*;
 use bls::Signature;
 use int_to_bytes::int_to_bytes4;
 use serde_derive::Deserialize;
+use test_utils::u8_from_hex_str;
 
 const GWEI: u64 = 1_000_000_000;
 
@@ -57,6 +58,7 @@ pub struct ChainSpec {
     pub far_future_epoch: Epoch,
     pub zero_hash: Hash256,
     pub empty_signature: Signature,
+    #[serde(deserialize_with = "u8_from_hex_str")]
     pub bls_withdrawal_prefix_byte: u8,
 
     /*

eth2/types/src/fork.rs

@@ -1,4 +1,7 @@
-use crate::{test_utils::TestRandom, ChainSpec, Epoch};
+use crate::{
+    test_utils::{fork_from_hex_str, TestRandom},
+    ChainSpec, Epoch,
+};
 use int_to_bytes::int_to_bytes4;
 use rand::RngCore;
 use serde_derive::{Deserialize, Serialize};
@@ -12,7 +15,9 @@ use test_random_derive::TestRandom;
     Debug, Clone, PartialEq, Default, Serialize, Deserialize, Encode, Decode, TreeHash, TestRandom,
 )]
 pub struct Fork {
+    #[serde(deserialize_with = "fork_from_hex_str")]
     pub previous_version: [u8; 4],
+    #[serde(deserialize_with = "fork_from_hex_str")]
     pub current_version: [u8; 4],
     pub epoch: Epoch,
 }

eth2/types/src/test_utils/mod.rs

@@ -2,6 +2,7 @@
 mod macros;
 mod generate_deterministic_keypairs;
 mod keypairs_file;
+mod serde_utils;
 mod test_random;
 mod testing_attestation_builder;
 mod testing_attestation_data_builder;
@@ -17,6 +18,7 @@ mod testing_voluntary_exit_builder;
 pub use generate_deterministic_keypairs::generate_deterministic_keypairs;
 pub use keypairs_file::KeypairsFile;
 pub use rand::{prng::XorShiftRng, SeedableRng};
+pub use serde_utils::{fork_from_hex_str, u8_from_hex_str};
 pub use test_random::TestRandom;
 pub use testing_attestation_builder::TestingAttestationBuilder;
 pub use testing_attestation_data_builder::TestingAttestationDataBuilder;

eth2/types/src/test_utils/serde_utils.rs

@@ -0,0 +1,28 @@
+use serde::de::Error;
+use serde::{Deserialize, Deserializer};
+
+pub fn u8_from_hex_str<'de, D>(deserializer: D) -> Result<u8, D::Error>
+where
+    D: Deserializer<'de>,
+{
+    let s: String = Deserialize::deserialize(deserializer)?;
+
+    u8::from_str_radix(&s.as_str()[2..], 16).map_err(D::Error::custom)
+}
+
+pub fn fork_from_hex_str<'de, D>(deserializer: D) -> Result<[u8; 4], D::Error>
+where
+    D: Deserializer<'de>,
+{
+    let s: String = Deserialize::deserialize(deserializer)?;
+    let mut array = [0 as u8; 4];
+    let decoded: Vec<u8> = hex::decode(&s.as_str()[2..]).map_err(D::Error::custom)?;
+
+    for (i, item) in array.iter_mut().enumerate() {
+        if i > decoded.len() {
+            break;
+        }
+        *item = decoded[i];
+    }
+    Ok(array)
+}

eth2/utils/bls/src/keypair.rs

@@ -14,4 +14,8 @@ impl Keypair {
         let pk = PublicKey::from_secret_key(&sk);
         Keypair { sk, pk }
     }
+
+    pub fn identifier(&self) -> String {
+        self.pk.concatenated_hex_id()
+    }
 }

eth2/utils/bls/src/serde_vistors.rs

@@ -8,13 +8,14 @@ impl<'de> Visitor<'de> for HexVisitor {
     type Value = Vec<u8>;
 
     fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
-        formatter.write_str("a hex string (without 0x prefix)")
+        formatter.write_str("a hex string (irrelevant of prefix)")
     }
 
     fn visit_str<E>(self, value: &str) -> Result<Self::Value, E>
     where
         E: de::Error,
     {
-        Ok(hex::decode(value).map_err(|e| de::Error::custom(format!("invalid hex ({:?})", e)))?)
+        Ok(hex::decode(value.trim_start_matches("0x"))
+            .map_err(|e| de::Error::custom(format!("invalid hex ({:?})", e)))?)
     }
 }

eth2/utils/bls/src/signature.rs

@@ -13,27 +13,35 @@ use ssz::{
 /// This struct is a wrapper upon a base type and provides helper functions (e.g., SSZ
 /// serialization).
 #[derive(Debug, PartialEq, Clone, Eq)]
-pub struct Signature(RawSignature);
+pub struct Signature {
+    signature: RawSignature,
+    is_empty: bool,
+}
 
 impl Signature {
     /// Instantiate a new Signature from a message and a SecretKey.
     pub fn new(msg: &[u8], domain: u64, sk: &SecretKey) -> Self {
-        Signature(RawSignature::new(msg, domain, sk.as_raw()))
+        Signature {
+            signature: RawSignature::new(msg, domain, sk.as_raw()),
+            is_empty: false,
+        }
     }
 
     /// Instantiate a new Signature from a message and a SecretKey, where the message has already
     /// been hashed.
     pub fn new_hashed(x_real_hashed: &[u8], x_imaginary_hashed: &[u8], sk: &SecretKey) -> Self {
-        Signature(RawSignature::new_hashed(
-            x_real_hashed,
-            x_imaginary_hashed,
-            sk.as_raw(),
-        ))
+        Signature {
+            signature: RawSignature::new_hashed(x_real_hashed, x_imaginary_hashed, sk.as_raw()),
+            is_empty: false,
+        }
     }
 
     /// Verify the Signature against a PublicKey.
     pub fn verify(&self, msg: &[u8], domain: u64, pk: &PublicKey) -> bool {
-        self.0.verify(msg, domain, pk.as_raw())
+        if self.is_empty {
+            return false;
+        }
+        self.signature.verify(msg, domain, pk.as_raw())
     }
 
     /// Verify the Signature against a PublicKey, where the message has already been hashed.
@@ -43,44 +51,72 @@ impl Signature {
         x_imaginary_hashed: &[u8],
         pk: &PublicKey,
     ) -> bool {
-        self.0
+        self.signature
             .verify_hashed(x_real_hashed, x_imaginary_hashed, pk.as_raw())
     }
 
     /// Returns the underlying signature.
     pub fn as_raw(&self) -> &RawSignature {
-        &self.0
+        &self.signature
     }
 
     /// Returns a new empty signature.
     pub fn empty_signature() -> Self {
-        // Empty Signature is currently being represented as BLS::Signature.point_at_infinity()
-        // However it should be represented as vec![0; 96] but this
-        // would require all signatures to be represented in byte form as opposed to Signature
+        // Set RawSignature = infinity
         let mut empty: Vec<u8> = vec![0; 96];
-        // Sets C_flag and B_flag to 1 and all else to 0
         empty[0] += u8::pow(2, 6) + u8::pow(2, 7);
-        Signature(RawSignature::from_bytes(&empty).unwrap())
+        Signature {
+            signature: RawSignature::from_bytes(&empty).unwrap(),
+            is_empty: true,
+        }
+    }
+
+    // Converts a BLS Signature to bytes
+    pub fn as_bytes(&self) -> Vec<u8> {
+        if self.is_empty {
+            return vec![0; 96];
+        }
+        self.signature.as_bytes()
+    }
+
+    // Convert bytes to BLS Signature
+    pub fn from_bytes(bytes: &[u8]) -> Result<Self, DecodeError> {
+        for byte in bytes {
+            if *byte != 0 {
+                let raw_signature =
+                    RawSignature::from_bytes(&bytes).map_err(|_| DecodeError::Invalid)?;
+                return Ok(Signature {
+                    signature: raw_signature,
+                    is_empty: false,
+                });
+            }
+        }
+        Ok(Signature::empty_signature())
+    }
+
+    // Check for empty Signature
+    pub fn is_empty(&self) -> bool {
+        self.is_empty
     }
 }
 
 impl Encodable for Signature {
     fn ssz_append(&self, s: &mut SszStream) {
-        s.append_vec(&self.0.as_bytes());
+        s.append_vec(&self.as_bytes());
     }
 }
 
 impl Decodable for Signature {
     fn ssz_decode(bytes: &[u8], i: usize) -> Result<(Self, usize), DecodeError> {
         let (sig_bytes, i) = decode_ssz_list(bytes, i)?;
-        let raw_sig = RawSignature::from_bytes(&sig_bytes).map_err(|_| DecodeError::TooShort)?;
-        Ok((Signature(raw_sig), i))
+        let signature = Signature::from_bytes(&sig_bytes)?;
+        Ok((signature, i))
     }
 }
 
 impl TreeHash for Signature {
     fn hash_tree_root(&self) -> Vec<u8> {
-        hash(&self.0.as_bytes())
+        hash(&self.as_bytes())
     }
 }
 

validator_client/Cargo.toml

@@ -4,6 +4,15 @@ version = "0.1.0"
 authors = ["Paul Hauner <paul@paulhauner.com>"]
 edition = "2018"
 
+[[bin]]
+name = "validator_client"
+path = "src/main.rs"
+
+[lib]
+name = "validator_client"
+path = "src/lib.rs"
+
+
 [dependencies]
 block_proposer = { path = "../eth2/block_proposer" }
 bls = { path = "../eth2/utils/bls" }
@@ -18,3 +27,4 @@ slog = "^2.2.3"
 slog-term = "^2.4.0"
 slog-async = "^2.3.0"
 ssz = { path = "../eth2/utils/ssz" }
+bincode = "^1.1.2"

validator_client/README.md

@@ -57,10 +57,30 @@ complete and return a block from the BN.
 
 ### Configuration
 
-Presently the validator specifics (pubkey, etc.) are randomly generated and the
-chain specification (slot length, BLS domain, etc.) are fixed to foundation
-parameters. This is temporary and will be upgrade so these parameters can be
-read from file (or initialized on first-boot).
+Validator configurations are stored in a separate data directory from the main Beacon Node
+binary. The validator data directory defaults to:
+`$HOME/.lighthouse-validator`, however an alternative can be specified on the command line
+with `--datadir`.
+
+The configuration directory structure looks like:
+```
+~/.lighthouse-validator
+    ├── 3cf4210d58ec
+    │   └── private.key
+    ├── 9b5d8b5be4e7
+    │   └── private.key
+    └── cf6e07188f48
+        └── private.key
+```
+
+Where the hex value of the directory is a portion of the validator public key.
+
+Validator keys must be generated using the separate `accounts_manager` binary, which will
+place the keys into this directory structure in a format compatible with the validator client.
+
+The chain specification (slot length, BLS domain, etc.) defaults to foundation
+parameters, however is temporary and an upgrade will allow these parameters to be
+read from a file (or initialized on first-boot).
 
 ## BN Communication
 

validator_client/src/config.rs

@@ -1,28 +1,39 @@
+use bincode;
+use bls::Keypair;
+use clap::ArgMatches;
+use slog::{debug, error, info};
 use std::fs;
+use std::fs::File;
+use std::io::{Error, ErrorKind};
 use std::path::PathBuf;
 use types::ChainSpec;
 
 /// Stores the core configuration for this validator instance.
 #[derive(Clone)]
-pub struct ClientConfig {
+pub struct Config {
+    /// The data directory, which stores all validator databases
     pub data_dir: PathBuf,
+    /// The server at which the Beacon Node can be contacted
     pub server: String,
+    /// The chain specification that we are connecting to
     pub spec: ChainSpec,
 }
 
-const DEFAULT_LIGHTHOUSE_DIR: &str = ".lighthouse-validators";
+const DEFAULT_PRIVATE_KEY_FILENAME: &str = "private.key";
 
-impl ClientConfig {
-    /// Build a new configuration from defaults.
-    pub fn default() -> Self {
+impl Default for Config {
+    fn default() -> Self {
         let data_dir = {
-            let home = dirs::home_dir().expect("Unable to determine home dir.");
-            home.join(DEFAULT_LIGHTHOUSE_DIR)
+            let home = dirs::home_dir().expect("Unable to determine home directory.");
+            home.join(".lighthouse-validator")
         };
         fs::create_dir_all(&data_dir)
             .unwrap_or_else(|_| panic!("Unable to create {:?}", &data_dir));
+
         let server = "localhost:50051".to_string();
+
         let spec = ChainSpec::foundation();
+
         Self {
             data_dir,
             server,
@@ -30,3 +41,114 @@ impl ClientConfig {
         }
     }
 }
+
+impl Config {
+    /// Build a new configuration from defaults, which are overrided by arguments provided.
+    pub fn parse_args(args: &ArgMatches, log: &slog::Logger) -> Result<Self, Error> {
+        let mut config = Config::default();
+
+        // Use the specified datadir, or default in the home directory
+        if let Some(datadir) = args.value_of("datadir") {
+            config.data_dir = PathBuf::from(datadir);
+            fs::create_dir_all(&config.data_dir)
+                .unwrap_or_else(|_| panic!("Unable to create {:?}", &config.data_dir));
+            info!(log, "Using custom data dir: {:?}", &config.data_dir);
+        };
+
+        if let Some(srv) = args.value_of("server") {
+            //TODO: I don't think this parses correctly a server & port combo
+            config.server = srv.to_string();
+            info!(log, "Using custom server: {:?}", &config.server);
+        };
+
+        // TODO: Permit loading a custom spec from file.
+        if let Some(spec_str) = args.value_of("spec") {
+            info!(log, "Using custom spec: {:?}", spec_str);
+            config.spec = match spec_str {
+                "foundation" => ChainSpec::foundation(),
+                "few_validators" => ChainSpec::few_validators(),
+                // Should be impossible due to clap's `possible_values(..)` function.
+                _ => unreachable!(),
+            };
+        };
+
+        Ok(config)
+    }
+
+    /// Try to load keys from validator_dir, returning None if none are found or an error.
+    pub fn fetch_keys(&self, log: &slog::Logger) -> Option<Vec<Keypair>> {
+        let key_pairs: Vec<Keypair> = fs::read_dir(&self.data_dir)
+            .unwrap()
+            .filter_map(|validator_dir| {
+                let validator_dir = validator_dir.ok()?;
+
+                if !(validator_dir.file_type().ok()?.is_dir()) {
+                    // Skip non-directories (i.e. no files/symlinks)
+                    return None;
+                }
+
+                let key_filename = validator_dir.path().join(DEFAULT_PRIVATE_KEY_FILENAME);
+
+                if !(key_filename.is_file()) {
+                    info!(
+                        log,
+                        "Private key is not a file: {:?}",
+                        key_filename.to_str()
+                    );
+                    return None;
+                }
+
+                debug!(
+                    log,
+                    "Deserializing private key from file: {:?}",
+                    key_filename.to_str()
+                );
+
+                let mut key_file = File::open(key_filename.clone()).ok()?;
+
+                let key: Keypair = if let Ok(key_ok) = bincode::deserialize_from(&mut key_file) {
+                    key_ok
+                } else {
+                    error!(
+                        log,
+                        "Unable to deserialize the private key file: {:?}", key_filename
+                    );
+                    return None;
+                };
+
+                let ki = key.identifier();
+                if ki != validator_dir.file_name().into_string().ok()? {
+                    error!(
+                        log,
+                        "The validator key ({:?}) did not match the directory filename {:?}.",
+                        ki,
+                        &validator_dir.path().to_string_lossy()
+                    );
+                    return None;
+                }
+                Some(key)
+            })
+            .collect();
+
+        // Check if it's an empty vector, and return none.
+        if key_pairs.is_empty() {
+            None
+        } else {
+            Some(key_pairs)
+        }
+    }
+
+    /// Saves a keypair to a file inside the appropriate validator directory. Returns the saved path filename.
+    pub fn save_key(&self, key: &Keypair) -> Result<PathBuf, Error> {
+        let validator_config_path = self.data_dir.join(key.identifier());
+        let key_path = validator_config_path.join(DEFAULT_PRIVATE_KEY_FILENAME);
+
+        fs::create_dir_all(&validator_config_path)?;
+
+        let mut key_file = File::create(&key_path)?;
+
+        bincode::serialize_into(&mut key_file, &key)
+            .map_err(|e| Error::new(ErrorKind::InvalidData, e))?;
+        Ok(key_path)
+    }
+}

validator_client/src/lib.rs

@@ -0,0 +1,3 @@
+pub mod config;
+
+pub use crate::config::Config;

validator_client/src/main.rs

@@ -1,17 +1,14 @@
 use self::block_producer_service::{BeaconBlockGrpcClient, BlockProducerService};
 use self::duties::{DutiesManager, DutiesManagerService, EpochDutiesMap};
-use crate::config::ClientConfig;
+use crate::config::Config;
 use block_proposer::{test_utils::LocalSigner, BlockProducer};
-use bls::Keypair;
 use clap::{App, Arg};
 use grpcio::{ChannelBuilder, EnvBuilder};
 use protos::services_grpc::{BeaconBlockServiceClient, ValidatorServiceClient};
-use slog::{error, info, o, Drain};
+use slog::{info, o, Drain};
 use slot_clock::SystemTimeSlotClock;
-use std::path::PathBuf;
 use std::sync::Arc;
 use std::thread;
-use types::ChainSpec;
 
 mod block_producer_service;
 mod config;
@@ -55,36 +52,11 @@ fn main() {
         )
         .get_matches();
 
-    let mut config = ClientConfig::default();
-
-    // Custom datadir
-    if let Some(dir) = matches.value_of("datadir") {
-        config.data_dir = PathBuf::from(dir.to_string());
-    }
-
-    // Custom server port
-    if let Some(server_str) = matches.value_of("server") {
-        if let Ok(addr) = server_str.parse::<u16>() {
-            config.server = addr.to_string();
-        } else {
-            error!(log, "Invalid address"; "server" => server_str);
-            return;
-        }
-    }
-
-    // TODO: Permit loading a custom spec from file.
-    // Custom spec
-    if let Some(spec_str) = matches.value_of("spec") {
-        match spec_str {
-            "foundation" => config.spec = ChainSpec::foundation(),
-            "few_validators" => config.spec = ChainSpec::few_validators(),
-            // Should be impossible due to clap's `possible_values(..)` function.
-            _ => unreachable!(),
-        };
-    }
+    let config = Config::parse_args(&matches, &log)
+        .expect("Unable to build a configuration for the validator client.");
 
     // Log configuration
-    info!(log, "";
+    info!(log, "Configuration parameters:";
           "data_dir" => &config.data_dir.to_str(),
           "server" => &config.server);
 
@@ -119,13 +91,13 @@ fn main() {
     let poll_interval_millis = spec.seconds_per_slot * 1000 / 10; // 10% epoch time precision.
     info!(log, "Starting block producer service"; "polls_per_epoch" => spec.seconds_per_slot * 1000 / poll_interval_millis);
 
+    let keypairs = config.fetch_keys(&log)
+        .expect("No key pairs found in configuration, they must first be generated with: account_manager generate.");
+
     /*
      * Start threads.
      */
     let mut threads = vec![];
-    // TODO: keypairs are randomly generated; they should be loaded from a file or generated.
-    // https://github.com/sigp/lighthouse/issues/160
-    let keypairs = vec![Keypair::random()];
 
     for keypair in keypairs {
         info!(log, "Starting validator services"; "validator" => keypair.pk.concatenated_hex_id());