feat(net): Networking Crate (#34)

### Description

Sets up a `net` crate based off of
paradigmxyz/reth-exex-examples#15.

### Metadata

Makes progress on #6

Cargo.toml

@@ -12,6 +12,7 @@ categories = ["cryptography", "cryptography::cryptocurrencies"]
 members = [
   "bin/hera",
   "bin/op-rs",
+  "crates/net",
   "crates/kona-providers",
   "crates/rollup",
   "crates/ser",
@@ -115,6 +116,9 @@ codegen-units = 1
 incremental = false
 
 [workspace.dependencies]
+# Workspace
+op-net = { path = "crates/net" }
+
 # Optimism
 superchain-registry = { version = "0.2.6", default-features = false }
 kona-primitives = { git = "https://github.com/ethereum-optimism/kona", default-features = true }
@@ -133,6 +137,9 @@ alloy-rlp = "0.3.4"
 # Tokio
 tokio = { version = "1.21", default-features = false }
 
+# SSZ
+ssz_rs = "0.9.0"
+
 # Reth
 reth = { git = "https://github.com/paradigmxyz/reth", version = "1.0.5" }
 reth-chainspec = { git = "https://github.com/paradigmxyz/reth", version = "1.0.5" }
@@ -149,12 +156,22 @@ reth-revm = { git = "https://github.com/paradigmxyz/reth", version = "1.0.5" }
 reth-evm = { git = "https://github.com/paradigmxyz/reth", version = "1.0.5" }
 reth-tracing = { git = "https://github.com/paradigmxyz/reth", version = "1.0.5" }
 
+# Networking
+snap = "1.1.1"
+discv5 = "0.6.0"
+openssl = { version = "0.10.66", features = ["vendored"] }
+libp2p-identity = { version = "0.2.9", features = [ "secp256k1" ] }
+libp2p = { version = "0.54.0", features = ["macros", "tokio", "tcp", "noise", "gossipsub", "ping", "yamux"] }
+
 # Misc
 tracing = "0.1.0"
 eyre = "0.6.12"
 clap = "4" 
+lazy_static = "1.5.0"
+futures = "0.3.30"
 async-trait = "0.1.81"
 hashbrown = "0.14.5"
 parking_lot = "0.12.3"
+unsigned-varint = "0.8.0"
 rand = { version = "0.8.3", features = ["small_rng"], default-features = false }
 url = "2.5.2"

crates/net/Cargo.toml

@@ -0,0 +1,35 @@
+[package]
+name = "op-net"
+description = "Networking library for OP Stack Consensus"
+version = "0.0.0"
+edition.workspace = true
+authors.workspace = true
+license.workspace = true
+keywords.workspace = true
+repository.workspace = true
+categories.workspace = true
+rust-version.workspace = true
+
+[dependencies]
+# Alloy
+alloy.workspace = true
+alloy-rlp.workspace = true
+
+# Kona
+kona-primitives.workspace = true
+
+# Networking
+ssz_rs.workspace = true
+snap.workspace = true
+futures.workspace = true
+discv5.workspace = true
+libp2p.workspace = true
+openssl.workspace = true
+libp2p-identity.workspace = true
+
+# Misc
+eyre.workspace = true
+tokio.workspace = true
+tracing.workspace = true
+lazy_static.workspace = true
+unsigned-varint.workspace = true

crates/net/README.md

@@ -0,0 +1,7 @@
+## Network Library
+
+Contains a gossipsub driver to run discv5 peer discovery and block gossip.
+
+## Acknowledgements
+
+Largely based off [magi][https://github.com/a16z/magi]'s [p2p module](https://github.com/a16z/magi/tree/master/src/network).

crates/net/src/builder.rs

@@ -0,0 +1,139 @@
+//! Network Builder Module.
+
+use alloy::primitives::Address;
+use eyre::Result;
+use std::net::SocketAddr;
+use tokio::sync::watch::channel;
+
+use libp2p::{
+    gossipsub::ConfigBuilder, noise::Config as NoiseConfig, tcp::Config as TcpConfig,
+    yamux::Config as YamuxConfig, Multiaddr, SwarmBuilder,
+};
+use libp2p_identity::Keypair;
+
+use crate::{
+    discovery::builder::DiscoveryBuilder,
+    driver::NetworkDriver,
+    gossip::{behaviour::Behaviour, config, driver::GossipDriver, handler::BlockHandler},
+    types::address::NetworkAddress,
+};
+
+/// Constructs a [NetworkDriver] for Optimism's consensus-layer.
+#[derive(Default)]
+pub struct NetworkDriverBuilder {
+    /// The chain ID of the network.
+    chain_id: Option<u64>,
+    /// The unsafe block signer.
+    unsafe_block_signer: Option<Address>,
+    /// The socket address that the service is listening on.
+    socket: Option<SocketAddr>,
+    /// The [ConfigBuilder] constructs the config for `gossipsub`.
+    inner: Option<ConfigBuilder>,
+    /// The [Keypair] for the node.
+    keypair: Option<Keypair>,
+    /// The [TcpConfig] for the swarm.
+    tcp_config: Option<TcpConfig>,
+    // /// The [NoiseConfig] for the swarm.
+    // noise_config: Option<NoiseConfig>,
+    /// The [YamuxConfig] for the swarm.
+    yamux_config: Option<YamuxConfig>,
+}
+
+impl NetworkDriverBuilder {
+    /// Creates a new [NetworkDriverBuilder].
+    pub fn new() -> Self {
+        Self::default()
+    }
+
+    /// Specifies the chain ID of the network.
+    pub fn with_chain_id(&mut self, chain_id: u64) -> &mut Self {
+        self.chain_id = Some(chain_id);
+        self
+    }
+
+    /// Specifies the unsafe block signer.
+    pub fn with_unsafe_block_signer(&mut self, unsafe_block_signer: Address) -> &mut Self {
+        self.unsafe_block_signer = Some(unsafe_block_signer);
+        self
+    }
+
+    /// Specifies the socket address that the service is listening on.
+    pub fn with_socket(&mut self, socket: SocketAddr) -> &mut Self {
+        self.socket = Some(socket);
+        self
+    }
+
+    /// Specifies the keypair for the node.
+    pub fn with_keypair(&mut self, keypair: Keypair) -> &mut Self {
+        self.keypair = Some(keypair);
+        self
+    }
+
+    /// Specifies the [TcpConfig] for the swarm.
+    pub fn with_tcp_config(&mut self, tcp_config: TcpConfig) -> &mut Self {
+        self.tcp_config = Some(tcp_config);
+        self
+    }
+
+    // /// Specifies the [NoiseConfig] for the swarm.
+    // pub fn with_noise_config(&mut self, noise_config: NoiseConfig) -> &mut Self {
+    //     self.noise_config = Some(noise_config);
+    //     self
+    // }
+
+    /// Specifies the [YamuxConfig] for the swarm.
+    pub fn with_yamux_config(&mut self, yamux_config: YamuxConfig) -> &mut Self {
+        self.yamux_config = Some(yamux_config);
+        self
+    }
+
+    // TODO: extend builder with [ConfigBuilder] methods.
+
+    /// Specifies the [ConfigBuilder] for the `gossipsub` configuration.
+    pub fn with_gossip_config(&mut self, inner: ConfigBuilder) -> &mut Self {
+        self.inner = Some(inner);
+        self
+    }
+
+    /// Builds the [NetworkDriver].
+    pub fn build(self) -> Result<NetworkDriver> {
+        // Build the config for gossipsub.
+        let config = self.inner.unwrap_or(config::default_config_builder()).build()?;
+        let unsafe_block_signer =
+            self.unsafe_block_signer.ok_or_else(|| eyre::eyre!("unsafe block signer not set"))?;
+        let chain_id = self.chain_id.ok_or_else(|| eyre::eyre!("chain ID not set"))?;
+
+        // Create the block handler.
+        let (unsafe_block_signer_sender, unsafe_block_signer_recv) = channel(unsafe_block_signer);
+        let (handler, unsafe_block_recv) = BlockHandler::new(chain_id, unsafe_block_signer_recv);
+
+        // Construct the gossipsub behaviour.
+        let behaviour = Behaviour::new(config, &[Box::new(handler.clone())])?;
+
+        // Build the swarm.
+        let keypair = self.keypair.unwrap_or(Keypair::generate_secp256k1());
+        let swarm = SwarmBuilder::with_existing_identity(keypair)
+            .with_tokio()
+            .with_tcp(self.tcp_config.unwrap_or_default(), NoiseConfig::new, || {
+                self.yamux_config.unwrap_or_default()
+            })?
+            .with_behaviour(|_| behaviour)?
+            .build();
+        let addr = self.socket.ok_or_else(|| eyre::eyre!("socket address not set"))?;
+        let addr = NetworkAddress::try_from(addr)?;
+        let swarm_addr = Multiaddr::from(addr);
+        let swarm = GossipDriver::new(swarm, swarm_addr);
+
+        // Build the discovery service
+        let discovery =
+            DiscoveryBuilder::new().with_address(addr).with_chain_id(chain_id).build()?;
+
+        Ok(NetworkDriver {
+            unsafe_block_recv,
+            unsafe_block_signer_sender,
+            handler,
+            swarm,
+            discovery,
+        })
+    }
+}

crates/net/src/discovery/bootnodes.rs

@@ -0,0 +1,22 @@
+//! Bootnodes for consensus network discovery.
+
+use discv5::enr::{CombinedKey, Enr};
+use lazy_static::lazy_static;
+use std::str::FromStr;
+
+lazy_static! {
+    /// Default bootnodes to use.
+    pub static ref BOOTNODES: Vec<Enr<CombinedKey>> = [
+        // Optimism Mainnet Bootnodes
+        Enr::from_str("enr:-J64QBbwPjPLZ6IOOToOLsSjtFUjjzN66qmBZdUexpO32Klrc458Q24kbty2PdRaLacHM5z-cZQr8mjeQu3pik6jPSOGAYYFIqBfgmlkgnY0gmlwhDaRWFWHb3BzdGFja4SzlAUAiXNlY3AyNTZrMaECmeSnJh7zjKrDSPoNMGXoopeDF4hhpj5I0OsQUUt4u8uDdGNwgiQGg3VkcIIkBg").unwrap(),
+        Enr::from_str("enr:-J64QAlTCDa188Hl1OGv5_2Kj2nWCsvxMVc_rEnLtw7RPFbOfqUOV6khXT_PH6cC603I2ynY31rSQ8sI9gLeJbfFGaWGAYYFIrpdgmlkgnY0gmlwhANWgzCHb3BzdGFja4SzlAUAiXNlY3AyNTZrMaECkySjcg-2v0uWAsFsZZu43qNHppGr2D5F913Qqs5jDCGDdGNwgiQGg3VkcIIkBg").unwrap(),
+        Enr::from_str("enr:-J24QGEzN4mJgLWNTUNwj7riVJ2ZjRLenOFccl2dbRFxHHOCCZx8SXWzgf-sLzrGs6QgqSFCvGXVgGPBkRkfOWlT1-iGAYe6Cu93gmlkgnY0gmlwhCJBEUSHb3BzdGFja4OkAwCJc2VjcDI1NmsxoQLuYIwaYOHg3CUQhCkS-RsSHmUd1b_x93-9yQ5ItS6udIN0Y3CCIyuDdWRwgiMr").unwrap(),
+
+        // Base Mainnet Bootnodes
+        Enr::from_str("enr:-J24QNz9lbrKbN4iSmmjtnr7SjUMk4zB7f1krHZcTZx-JRKZd0kA2gjufUROD6T3sOWDVDnFJRvqBBo62zuF-hYCohOGAYiOoEyEgmlkgnY0gmlwhAPniryHb3BzdGFja4OFQgCJc2VjcDI1NmsxoQKNVFlCxh_B-716tTs-h1vMzZkSs1FTu_OYTNjgufplG4N0Y3CCJAaDdWRwgiQG").unwrap(),
+        Enr::from_str("enr:-J24QH-f1wt99sfpHy4c0QJM-NfmsIfmlLAMMcgZCUEgKG_BBYFc6FwYgaMJMQN5dsRBJApIok0jFn-9CS842lGpLmqGAYiOoDRAgmlkgnY0gmlwhLhIgb2Hb3BzdGFja4OFQgCJc2VjcDI1NmsxoQJ9FTIv8B9myn1MWaC_2lJ-sMoeCDkusCsk4BYHjjCq04N0Y3CCJAaDdWRwgiQG").unwrap(),
+        Enr::from_str("enr:-J24QDXyyxvQYsd0yfsN0cRr1lZ1N11zGTplMNlW4xNEc7LkPXh0NAJ9iSOVdRO95GPYAIc6xmyoCCG6_0JxdL3a0zaGAYiOoAjFgmlkgnY0gmlwhAPckbGHb3BzdGFja4OFQgCJc2VjcDI1NmsxoQJwoS7tzwxqXSyFL7g0JM-KWVbgvjfB8JA__T7yY_cYboN0Y3CCJAaDdWRwgiQG").unwrap(),
+        Enr::from_str("enr:-J24QHmGyBwUZXIcsGYMaUqGGSl4CFdx9Tozu-vQCn5bHIQbR7On7dZbU61vYvfrJr30t0iahSqhc64J46MnUO2JvQaGAYiOoCKKgmlkgnY0gmlwhAPnCzSHb3BzdGFja4OFQgCJc2VjcDI1NmsxoQINc4fSijfbNIiGhcgvwjsjxVFJHUstK9L1T8OTKUjgloN0Y3CCJAaDdWRwgiQG").unwrap(),
+        Enr::from_str("enr:-J24QG3ypT4xSu0gjb5PABCmVxZqBjVw9ca7pvsI8jl4KATYAnxBmfkaIuEqy9sKvDHKuNCsy57WwK9wTt2aQgcaDDyGAYiOoGAXgmlkgnY0gmlwhDbGmZaHb3BzdGFja4OFQgCJc2VjcDI1NmsxoQIeAK_--tcLEiu7HvoUlbV52MspE0uCocsx1f_rYvRenIN0Y3CCJAaDdWRwgiQG").unwrap(),
+    ].to_vec();
+}

crates/net/src/discovery/builder.rs

@@ -0,0 +1,59 @@
+//! Contains a builder for the discovery service.
+
+use crate::{
+    discovery::driver::DiscoveryDriver,
+    types::{address::NetworkAddress, enr::OpStackEnr},
+};
+use discv5::{
+    enr::{CombinedKey, Enr},
+    ConfigBuilder, Discv5, ListenConfig,
+};
+use eyre::Result;
+
+use crate::types::enr::OP_CL_KEY;
+
+/// Discovery service builder.
+#[derive(Debug, Default, Clone)]
+pub struct DiscoveryBuilder {
+    /// The discovery service address.
+    address: Option<NetworkAddress>,
+    /// The chain ID of the network.
+    chain_id: Option<u64>,
+}
+
+impl DiscoveryBuilder {
+    /// Creates a new discovery builder.
+    pub fn new() -> Self {
+        Self::default()
+    }
+
+    /// Sets the discovery service address.
+    pub fn with_address(mut self, address: NetworkAddress) -> Self {
+        self.address = Some(address);
+        self
+    }
+
+    /// Sets the chain ID of the network.
+    pub fn with_chain_id(mut self, chain_id: u64) -> Self {
+        self.chain_id = Some(chain_id);
+        self
+    }
+
+    /// Builds a [DiscoveryDriver].
+    pub fn build(self) -> Result<DiscoveryDriver> {
+        let addr = self.address.ok_or_else(|| eyre::eyre!("address not set"))?;
+        let chain_id = self.chain_id.ok_or_else(|| eyre::eyre!("chain ID not set"))?;
+        let opstack = OpStackEnr::new(chain_id, 0);
+        let opstack_data: Vec<u8> = opstack.into();
+
+        let key = CombinedKey::generate_secp256k1();
+        let enr = Enr::builder().add_value_rlp(OP_CL_KEY, opstack_data.into()).build(&key)?;
+        let listen_config = ListenConfig::from_ip(addr.ip.into(), addr.port);
+        let config = ConfigBuilder::new(listen_config).build();
+
+        let disc = Discv5::new(enr, key, config)
+            .map_err(|_| eyre::eyre!("could not create disc service"))?;
+
+        Ok(DiscoveryDriver::new(disc, chain_id))
+    }
+}