feat(net): add discv4 crate (#113)

* port kad

* feat: port kad bucket

* feat: add discv4

* chore: rustfmt

* cargo update

* just reuse discv5 table

* test: add rlp tests

* message encoding

* feat: impl codec roundtrip testing

* more work in message handling

* implement ping

* feat: impl commands

* cleanup

* more cleanup

* trim config

* more docs

* feat: implement recursive lookup

* docs

* cleanup config

* feat: implement update stream

* chore: config cleanup

* docs: add crate docs

* feat: more testing

* fix deny

* clarify ring

* docs: more docs

* use discv5 master

* docs: address review and add comments

* update readme

* rustmft

* chore(clippy): make clippy happy

Cargo.toml

@@ -10,6 +10,7 @@ members = [
     "crates/net/p2p",
     "crates/net/ecies",
     "crates/net/eth-wire",
+    "crates/net/discv4",
     "crates/net/rpc",
     "crates/net/rpc-api",
     "crates/net/rpc-types",

crates/net/discv4/Cargo.toml

@@ -0,0 +1,42 @@
+[package]
+name = "reth-discv4"
+version = "0.1.0"
+edition = "2021"
+license = "Apache-2.0"
+repository = "https://github.com/foundry-rs/reth"
+readme = "README.md"
+description = """
+Ethereum network support
+"""
+
+[dependencies]
+# reth
+reth-primitives = { path = "../../primitives" }
+reth-rlp = { path = "../../common/rlp" }
+reth-rlp-derive = { path = "../../common/rlp-derive" }
+
+# ethereum
+discv5 = { git = "https://github.com/sigp/discv5" }
+secp256k1 = { version = "0.24", features = [
+    "global-context",
+    "rand-std",
+    "recovery",
+] }
+
+# async/futures
+tokio = { version = "1", features = ["io-util", "net", "time"] }
+tokio-stream = "0.1"
+
+# misc
+generic-array = "0.14"
+tracing = "0.1"
+bytes = "1.2"
+thiserror = "1.0"
+url = "2.3"
+hex = "0.4"
+public-ip = "0.2"
+
+[dev-dependencies]
+rand = "0.8"
+tokio = { version = "1", features = ["full"] }
+tracing-test = "0.2"

crates/net/discv4/README.md

@@ -0,0 +1,22 @@
+# <h1 align="center"> discv4 </h1>
+
+This is a rust implementation of
+the [Discovery v4](https://github.com/ethereum/devp2p/blob/40ab248bf7e017e83cc9812a4e048446709623e8/discv4.md)
+peer discovery protocol.
+
+For comparison to Discovery v5,
+see [discv5#comparison-with-node-discovery-v4](https://github.com/ethereum/devp2p/blob/40ab248bf7e017e83cc9812a4e048446709623e8/discv5/discv5.md#comparison-with-node-discovery-v4)
+
+This is inspired by the [discv5](https://github.com/sigp/discv5) crate and reuses its kademlia implementation.
+
+## Finding peers
+
+The discovery service continuously attempts to connect to other nodes on the network until it has found enough peers.
+If UPnP (Universal Plug and Play) is supported by the router the service is running on, it will also accept connections
+from external nodes. In the discovery protocol, nodes exchange information about where the node can be reached to
+eventually establish RLPx sessions.
+
+## Trouble Shooting
+
+The discv4 protocol depends on the local system clock. If the clock is not accurate it can cause connectivity issues
+because the expiration timestamps might be wrong.

crates/net/discv4/src/bootnodes.rs

@@ -0,0 +1,61 @@
+//! Various known bootstrap nodes for networks
+
+// <https://github.com/ledgerwatch/erigon/blob/610e648dc43ec8cd6563313e28f06f534a9091b3/params/bootnodes.go>
+
+use crate::node::NodeRecord;
+
+/// Ethereum Foundation Go Bootnodes
+pub static MAINNET_BOOTNODES : [&str; 8] = [
+    "enode://d860a01f9722d78051619d1e2351aba3f43f943f6f00718d1b9baa4101932a1f5011f16bb2b1bb35db20d6fe28fa0bf09636d26a87d31de9ec6203eeedb1f666@18.138.108.67:30303",   // bootnode-aws-ap-southeast-1-001
+    "enode://22a8232c3abc76a16ae9d6c3b164f98775fe226f0917b0ca871128a74a8e9630b458460865bab457221f1d448dd9791d24c4e5d88786180ac185df813a68d4de@3.209.45.79:30303",     // bootnode-aws-us-east-1-001
+    "enode://8499da03c47d637b20eee24eec3c356c9a2e6148d6fe25ca195c7949ab8ec2c03e3556126b0d7ed644675e78c4318b08691b7b57de10e5f0d40d05b09238fa0a@52.187.207.27:30303",   // bootnode-azure-australiaeast-001
+    "enode://103858bdb88756c71f15e9b5e09b56dc1be52f0a5021d46301dbbfb7e130029cc9d0d6f73f693bc29b665770fff7da4d34f3c6379fe12721b5d7a0bcb5ca1fc1@191.234.162.198:30303", // bootnode-azure-brazilsouth-001
+    "enode://715171f50508aba88aecd1250af392a45a330af91d7b90701c436b618c86aaa1589c9184561907bebbb56439b8f8787bc01f49a7c77276c58c1b09822d75e8e8@52.231.165.108:30303",  // bootnode-azure-koreasouth-001
+    "enode://5d6d7cd20d6da4bb83a1d28cadb5d409b64edf314c0335df658c1a54e32c7c4a7ab7823d57c39b6a757556e68ff1df17c748b698544a55cb488b52479a92b60f@104.42.217.25:30303",   // bootnode-azure-westus-001
+    "enode://2b252ab6a1d0f971d9722cb839a42cb81db019ba44c08754628ab4a823487071b5695317c8ccd085219c3a03af063495b2f1da8d18218da2d6a82981b45e6ffc@65.108.70.101:30303",   // bootnode-hetzner-hel
+    "enode://4aeb4ab6c14b23e2c4cfdce879c04b0748a20d8e9b59e25ded2a08143e265c6c25936e74cbc8e641e3312ca288673d91f2f93f8e277de3cfa444ecdaaf982052@157.90.35.166:30303",   // bootnode-hetzner-fsn
+];
+
+/// SEPOLIA BOOTNODES
+pub static SEPOLIA_BOOTNODES : [&str; 2] = [
+    // geth
+    "enode://9246d00bc8fd1742e5ad2428b80fc4dc45d786283e05ef6edbd9002cbc335d40998444732fbe921cb88e1d2c73d1b1de53bae6a2237996e9bfe14f871baf7066@18.168.182.86:30303",
+    // besu
+    "enode://ec66ddcf1a974950bd4c782789a7e04f8aa7110a72569b6e65fcd51e937e74eed303b1ea734e4d19cfaec9fbff9b6ee65bf31dcb50ba79acce9dd63a6aca61c7@52.14.151.177:30303",
+];
+
+/// GOERLI bootnodes
+pub static GOERLI_BOOTNODES : [&str; 7] = [
+// Upstream bootnodes
+"enode://011f758e6552d105183b1761c5e2dea0111bc20fd5f6422bc7f91e0fabbec9a6595caf6239b37feb773dddd3f87240d99d859431891e4a642cf2a0a9e6cbb98a@51.141.78.53:30303",
+"enode://176b9417f511d05b6b2cf3e34b756cf0a7096b3094572a8f6ef4cdcb9d1f9d00683bf0f83347eebdf3b81c3521c2332086d9592802230bf528eaf606a1d9677b@13.93.54.137:30303",
+"enode://46add44b9f13965f7b9875ac6b85f016f341012d84f975377573800a863526f4da19ae2c620ec73d11591fa9510e992ecc03ad0751f53cc02f7c7ed6d55c7291@94.237.54.114:30313",
+"enode://b5948a2d3e9d486c4d75bf32713221c2bd6cf86463302339299bd227dc2e276cd5a1c7ca4f43a0e9122fe9af884efed563bd2a1fd28661f3b5f5ad7bf1de5949@18.218.250.66:30303",
+
+// Ethereum Foundation bootnode
+"enode://a61215641fb8714a373c80edbfa0ea8878243193f57c96eeb44d0bc019ef295abd4e044fd619bfc4c59731a73fb79afe84e9ab6da0c743ceb479cbb6d263fa91@3.11.147.67:30303",
+
+// Goerli Initiative bootnodes
+"enode://d4f764a48ec2a8ecf883735776fdefe0a3949eb0ca476bd7bc8d0954a9defe8fea15ae5da7d40b5d2d59ce9524a99daedadf6da6283fca492cc80b53689fb3b3@46.4.99.122:32109",
+"enode://d2b720352e8216c9efc470091aa91ddafc53e222b32780f505c817ceef69e01d5b0b0797b69db254c586f493872352f5a022b4d8479a00fc92ec55f9ad46a27e@88.99.70.182:30303",
+];
+
+/// Returns parsed mainnet nodes
+pub fn mainnet_nodes() -> Vec<NodeRecord> {
+    parse_nodes(&MAINNET_BOOTNODES[..])
+}
+
+/// Returns parsed goerli nodes
+pub fn goerli_nodes() -> Vec<NodeRecord> {
+    parse_nodes(&GOERLI_BOOTNODES[..])
+}
+
+/// Returns parsed sepolia nodes
+pub fn sepolia_nodes() -> Vec<NodeRecord> {
+    parse_nodes(&SEPOLIA_BOOTNODES[..])
+}
+
+/// Parses all the nodes
+pub fn parse_nodes(nodes: impl IntoIterator<Item = impl AsRef<str>>) -> Vec<NodeRecord> {
+    nodes.into_iter().map(|s| s.as_ref().parse().unwrap()).collect()
+}

crates/net/discv4/src/config.rs

@@ -0,0 +1,128 @@
+use crate::node::NodeRecord;
+use discv5::PermitBanList;
+///! A set of configuration parameters to tune the discovery protocol.
+// This basis of this file has been taken from the discv5 codebase:
+// https://github.com/sigp/discv5
+use std::collections::HashSet;
+use std::time::Duration;
+
+/// Configuration parameters that define the performance of the discovery network.
+#[derive(Clone, Debug)]
+pub struct Discv4Config {
+    /// Whether to enable the incoming packet filter. Default: false.
+    pub enable_packet_filter: bool,
+    /// The number of retries for each UDP request. Default: 1.
+    pub request_retries: u8,
+    /// The time between pings to ensure connectivity amongst connected nodes. Default: 300
+    /// seconds.
+    pub ping_interval: Duration,
+    /// The duration of we consider a ping timed out.
+    pub ping_timeout: Duration,
+    /// The rate at which lookups should be triggered.
+    pub lookup_interval: Duration,
+    /// The duration of we consider a FindNode request timed out.
+    pub find_node_timeout: Duration,
+    /// The duration we set for neighbours responses
+    pub neighbours_timeout: Duration,
+    /// A set of lists that permit or ban IP's or NodeIds from the server. See
+    /// `crate::PermitBanList`.
+    pub permit_ban_list: PermitBanList,
+    /// Set the default duration for which nodes are banned for. This timeouts are checked every 5
+    /// minutes, so the precision will be to the nearest 5 minutes. If set to `None`, bans from
+    /// the filter will last indefinitely. Default is 1 hour.
+    pub ban_duration: Option<Duration>,
+    /// Nodes to boot from.
+    pub bootstrap_nodes: HashSet<NodeRecord>,
+}
+
+impl Discv4Config {
+    /// Returns a new default builder instance
+    pub fn builder() -> Discv4ConfigBuilder {
+        Default::default()
+    }
+}
+
+impl Default for Discv4Config {
+    fn default() -> Self {
+        Self {
+            enable_packet_filter: false,
+            request_retries: 1,
+            ping_interval: Duration::from_secs(300),
+            ping_timeout: Duration::from_secs(5),
+            find_node_timeout: Duration::from_secs(2),
+            neighbours_timeout: Duration::from_secs(30),
+            lookup_interval: Duration::from_secs(20),
+            permit_ban_list: PermitBanList::default(),
+            ban_duration: Some(Duration::from_secs(3600)), // 1 hour
+            bootstrap_nodes: Default::default(),
+        }
+    }
+}
+
+#[derive(Debug, Default)]
+pub struct Discv4ConfigBuilder {
+    config: Discv4Config,
+}
+
+impl Discv4ConfigBuilder {
+    /// Whether to enable the incoming packet filter.
+    pub fn enable_packet_filter(&mut self) -> &mut Self {
+        self.config.enable_packet_filter = true;
+        self
+    }
+
+    /// The number of retries for each UDP request.
+    pub fn request_retries(&mut self, retries: u8) -> &mut Self {
+        self.config.request_retries = retries;
+        self
+    }
+
+    /// The time between pings to ensure connectivity amongst connected nodes.
+    pub fn ping_interval(&mut self, interval: Duration) -> &mut Self {
+        self.config.ping_interval = interval;
+        self
+    }
+
+    /// Sets the timeout for pings
+    pub fn ping_timeout(&mut self, duration: Duration) -> &mut Self {
+        self.config.ping_timeout = duration;
+        self
+    }
+
+    /// A set of lists that permit or ban IP's or NodeIds from the server. See
+    /// `crate::PermitBanList`.
+    pub fn permit_ban_list(&mut self, list: PermitBanList) -> &mut Self {
+        self.config.permit_ban_list = list;
+        self
+    }
+
+    /// Sets the lookup interval duration.
+    pub fn lookup_interval(&mut self, lookup_interval: Duration) -> &mut Self {
+        self.config.lookup_interval = lookup_interval;
+        self
+    }
+
+    /// Set the default duration for which nodes are banned for. This timeouts are checked every 5
+    /// minutes, so the precision will be to the nearest 5 minutes. If set to `None`, bans from
+    /// the filter will last indefinitely. Default is 1 hour.
+    pub fn ban_duration(&mut self, ban_duration: Option<Duration>) -> &mut Self {
+        self.config.ban_duration = ban_duration;
+        self
+    }
+
+    /// Adds a boot node
+    pub fn add_boot_node(&mut self, node: NodeRecord) -> &mut Self {
+        self.config.bootstrap_nodes.insert(node);
+        self
+    }
+
+    /// Adds multiple boot nodes
+    pub fn add_boot_nodes(&mut self, nodes: impl IntoIterator<Item = NodeRecord>) -> &mut Self {
+        self.config.bootstrap_nodes.extend(nodes);
+        self
+    }
+
+    pub fn build(&mut self) -> Discv4Config {
+        self.config.clone()
+    }
+}

crates/net/discv4/src/error.rs

@@ -0,0 +1,36 @@
+//! Error types that can occur in this crate.
+
+use tokio::sync::{mpsc::error::SendError, oneshot::error::RecvError};
+
+/// Error thrown when decoding a UDP packet.
+#[derive(Debug, thiserror::Error)]
+#[allow(missing_docs)]
+pub enum DecodePacketError {
+    #[error("Failed to rlp decode: {0:?}")]
+    Rlp(#[from] reth_rlp::DecodeError),
+    #[error("Received packet len too short.")]
+    PacketTooShort,
+    #[error("Hash of the header not equals to the hash of the data.")]
+    HashMismatch,
+    #[error("Message id {0} is not supported.")]
+    UnknownMessage(u8),
+    #[error("Failed to recover public key: {0:?}")]
+    Secp256k1(#[from] secp256k1::Error),
+}
+
+/// High level errors that can occur when interacting with the discovery service
+#[derive(Debug, thiserror::Error)]
+pub enum Discv4Error {
+    /// Failed to send a command over the channel
+    #[error("Failed to send on a closed channel")]
+    Send,
+    /// Failed to receive a command response
+    #[error(transparent)]
+    Receive(#[from] RecvError),
+}
+
+impl<T> From<SendError<T>> for Discv4Error {
+    fn from(_: SendError<T>) -> Self {
+        Discv4Error::Send
+    }
+}