feat: added seed_peers to consensus global config (#2920)

It will allow us to announce the recommended default list of peers to
all ENs without manual intervention.
Fixes BFT-509.

---------

Co-authored-by: Bruno França <bruno@franca.xyz>

core/lib/config/src/configs/consensus.rs

@@ -92,6 +92,8 @@ pub struct GenesisSpec {
     pub leader: ValidatorPublicKey,
     /// Address of the registry contract.
     pub registry_address: Option<ethabi::Address>,
+    /// Recommended list of peers to connect to.
+    pub seed_peers: BTreeMap<NodePublicKey, Host>,
 }
 
 #[derive(Clone, Debug, PartialEq, Default)]

core/lib/config/src/testonly.rs

@@ -774,14 +774,20 @@ impl Distribution<configs::consensus::WeightedAttester> for EncodeDist {
 
 impl Distribution<configs::consensus::GenesisSpec> for EncodeDist {
     fn sample<R: Rng + ?Sized>(&self, rng: &mut R) -> configs::consensus::GenesisSpec {
-        use configs::consensus::{GenesisSpec, ProtocolVersion, ValidatorPublicKey};
+        use configs::consensus::{
+            GenesisSpec, Host, NodePublicKey, ProtocolVersion, ValidatorPublicKey,
+        };
         GenesisSpec {
             chain_id: L2ChainId::default(),
             protocol_version: ProtocolVersion(self.sample(rng)),
             validators: self.sample_collect(rng),
             attesters: self.sample_collect(rng),
             leader: ValidatorPublicKey(self.sample(rng)),
             registry_address: self.sample_opt(|| rng.gen()),
+            seed_peers: self
+                .sample_range(rng)
+                .map(|_| (NodePublicKey(self.sample(rng)), Host(self.sample(rng))))
+                .collect(),
         }
     }
 }

core/lib/dal/Cargo.toml

@@ -19,6 +19,7 @@ zksync_utils.workspace = true
 zksync_system_constants.workspace = true
 zksync_contracts.workspace = true
 zksync_types.workspace = true
+zksync_concurrency.workspace = true
 zksync_consensus_roles.workspace = true
 zksync_consensus_storage.workspace = true
 zksync_protobuf.workspace = true

core/lib/dal/src/consensus/mod.rs

@@ -5,8 +5,11 @@ mod testonly;
 #[cfg(test)]
 mod tests;
 
+use std::collections::BTreeMap;
+
 use anyhow::{anyhow, Context as _};
-use zksync_consensus_roles::{attester, validator};
+use zksync_concurrency::net;
+use zksync_consensus_roles::{attester, node, validator};
 use zksync_protobuf::{read_required, required, ProtoFmt, ProtoRepr};
 use zksync_types::{
     abi, ethabi,
@@ -27,6 +30,23 @@ use crate::models::{parse_h160, parse_h256};
 pub struct GlobalConfig {
     pub genesis: validator::Genesis,
     pub registry_address: Option<ethabi::Address>,
+    pub seed_peers: BTreeMap<node::PublicKey, net::Host>,
+}
+
+impl ProtoRepr for proto::NodeAddr {
+    type Type = (node::PublicKey, net::Host);
+    fn read(&self) -> anyhow::Result<Self::Type> {
+        Ok((
+            read_required(&self.key).context("key")?,
+            net::Host(required(&self.addr).context("addr")?.clone()),
+        ))
+    }
+    fn build(this: &Self::Type) -> Self {
+        Self {
+            key: Some(this.0.build()),
+            addr: Some(this.1 .0.clone()),
+        }
+    }
 }
 
 impl ProtoFmt for GlobalConfig {
@@ -41,13 +61,25 @@ impl ProtoFmt for GlobalConfig {
                 .map(|a| parse_h160(a))
                 .transpose()
                 .context("registry_address")?,
+            seed_peers: r
+                .seed_peers
+                .iter()
+                .enumerate()
+                .map(|(i, e)| e.read().context(i))
+                .collect::<Result<_, _>>()
+                .context("seed_peers")?,
         })
     }
 
     fn build(&self) -> Self::Proto {
         Self::Proto {
             genesis: Some(self.genesis.build()),
             registry_address: self.registry_address.map(|a| a.as_bytes().to_vec()),
+            seed_peers: self
+                .seed_peers
+                .iter()
+                .map(|(k, v)| ProtoRepr::build(&(k.clone(), v.clone())))
+                .collect(),
         }
     }
 }

core/lib/dal/src/consensus/proto/mod.proto

@@ -4,6 +4,7 @@ package zksync.dal;
 
 import "zksync/roles/validator.proto";
 import "zksync/roles/attester.proto";
+import "zksync/roles/node.proto";
 
 message Payload {
   // zksync-era ProtocolVersionId
@@ -122,9 +123,15 @@ message AttesterCommittee {
   repeated roles.attester.WeightedAttester members = 1; // required
 }
 
+message NodeAddr {
+  optional roles.node.PublicKey key = 1; // required
+  optional string addr = 2; // required; Host
+}
+
 message GlobalConfig {
   optional roles.validator.Genesis genesis = 1; // required
   optional bytes registry_address = 2; // optional; H160
+  repeated NodeAddr seed_peers = 3;
 }
 
 message AttestationStatus {

core/lib/dal/src/consensus_dal.rs

@@ -66,6 +66,7 @@ impl ConsensusDal<'_, '_> {
             return Ok(Some(GlobalConfig {
                 genesis,
                 registry_address: None,
+                seed_peers: [].into(),
             }));
         }
         Ok(None)
@@ -184,6 +185,7 @@ impl ConsensusDal<'_, '_> {
             }
             .with_hash(),
             registry_address: old.registry_address,
+            seed_peers: old.seed_peers,
         };
         txn.consensus_dal().try_update_global_config(&new).await?;
         txn.commit().await?;
@@ -681,6 +683,7 @@ mod tests {
             let cfg = GlobalConfig {
                 genesis: genesis.with_hash(),
                 registry_address: Some(rng.gen()),
+                seed_peers: [].into(), // TODO: rng.gen() for Host
             };
             conn.consensus_dal()
                 .try_update_global_config(&cfg)
@@ -715,6 +718,7 @@ mod tests {
         let cfg = GlobalConfig {
             genesis: setup.genesis.clone(),
             registry_address: Some(rng.gen()),
+            seed_peers: [].into(),
         };
         conn.consensus_dal()
             .try_update_global_config(&cfg)

core/lib/protobuf_config/src/consensus.rs

@@ -71,6 +71,13 @@ impl ProtoRepr for proto::GenesisSpec {
                 .map(|x| parse_h160(x))
                 .transpose()
                 .context("registry_address")?,
+            seed_peers: self
+                .seed_peers
+                .iter()
+                .enumerate()
+                .map(|(i, e)| e.read().context(i))
+                .collect::<Result<_, _>>()
+                .context("seed_peers")?,
         })
     }
     fn build(this: &Self::Type) -> Self {
@@ -81,6 +88,11 @@ impl ProtoRepr for proto::GenesisSpec {
             attesters: this.attesters.iter().map(ProtoRepr::build).collect(),
             leader: Some(this.leader.0.clone()),
             registry_address: this.registry_address.map(|a| format!("{:?}", a)),
+            seed_peers: this
+                .seed_peers
+                .iter()
+                .map(|(k, v)| proto::NodeAddr::build(&(k.clone(), v.clone())))
+                .collect(),
         }
     }
 }
@@ -99,15 +111,25 @@ impl ProtoRepr for proto::RpcConfig {
     }
 }
 
+impl ProtoRepr for proto::NodeAddr {
+    type Type = (NodePublicKey, Host);
+    fn read(&self) -> anyhow::Result<Self::Type> {
+        Ok((
+            NodePublicKey(required(&self.key).context("key")?.clone()),
+            Host(required(&self.addr).context("addr")?.clone()),
+        ))
+    }
+    fn build(this: &Self::Type) -> Self {
+        Self {
+            key: Some(this.0 .0.clone()),
+            addr: Some(this.1 .0.clone()),
+        }
+    }
+}
+
 impl ProtoRepr for proto::Config {
     type Type = ConsensusConfig;
     fn read(&self) -> anyhow::Result<Self::Type> {
-        let read_addr = |e: &proto::NodeAddr| {
-            let key = NodePublicKey(required(&e.key).context("key")?.clone());
-            let addr = Host(required(&e.addr).context("addr")?.clone());
-            anyhow::Ok((key, addr))
-        };
-
         let max_payload_size = required(&self.max_payload_size)
             .and_then(|x| Ok((*x).try_into()?))
             .context("max_payload_size")?;
@@ -144,8 +166,9 @@ impl ProtoRepr for proto::Config {
                 .gossip_static_outbound
                 .iter()
                 .enumerate()
-                .map(|(i, e)| read_addr(e).context(i))
-                .collect::<Result<_, _>>()?,
+                .map(|(i, e)| e.read().context(i))
+                .collect::<Result<_, _>>()
+                .context("gossip_static_outbound")?,
             genesis_spec: read_optional_repr(&self.genesis_spec),
             rpc: read_optional_repr(&self.rpc_config),
         })
@@ -168,10 +191,7 @@ impl ProtoRepr for proto::Config {
             gossip_static_outbound: this
                 .gossip_static_outbound
                 .iter()
-                .map(|x| proto::NodeAddr {
-                    key: Some(x.0 .0.clone()),
-                    addr: Some(x.1 .0.clone()),
-                })
+                .map(|(k, v)| proto::NodeAddr::build(&(k.clone(), v.clone())))
                 .collect(),
             genesis_spec: this.genesis_spec.as_ref().map(ProtoRepr::build),
             rpc_config: this.rpc.as_ref().map(ProtoRepr::build),

core/lib/protobuf_config/src/proto/core/consensus.proto

@@ -31,10 +31,10 @@ package zksync.core.consensus;
 
 import "zksync/std.proto";
 
-// (public key, ip address) of a gossip network node.
+// (public key, host address) of a gossip network node.
 message NodeAddr {
   optional string key = 1; // required; NodePublicKey
-  optional string addr = 2; // required; IpAddr
+  optional string addr = 2; // required; Host
 }
 
 // Weighted member of a validator committee. 
@@ -58,6 +58,7 @@ message GenesisSpec {
   repeated WeightedAttester attesters = 5; // can be empty; attester committee.
   // Currently not in consensus genesis, but still a part of the global configuration.
   optional string registry_address = 6; // optional; H160
+  repeated NodeAddr seed_peers = 7;
 }
 
 // Per peer connection RPC rate limits.

core/node/consensus/src/config.rs

@@ -1,5 +1,5 @@
 //! Configuration utilities for the consensus component.
-use std::collections::HashMap;
+use std::collections::{BTreeMap, HashMap};
 
 use anyhow::Context as _;
 use secrecy::{ExposeSecret as _, Secret};
@@ -44,6 +44,7 @@ pub(super) struct GenesisSpec {
     pub(super) attesters: Option<attester::Committee>,
     pub(super) leader_selection: validator::LeaderSelectionMode,
     pub(super) registry_address: Option<ethabi::Address>,
+    pub(super) seed_peers: BTreeMap<node::PublicKey, net::Host>,
 }
 
 impl GenesisSpec {
@@ -55,6 +56,7 @@ impl GenesisSpec {
             attesters: cfg.genesis.attesters.clone(),
             leader_selection: cfg.genesis.leader_selection.clone(),
             registry_address: cfg.registry_address,
+            seed_peers: cfg.seed_peers.clone(),
         }
     }
 
@@ -98,6 +100,19 @@ impl GenesisSpec {
                 Some(attester::Committee::new(attesters).context("attesters")?)
             },
             registry_address: x.registry_address,
+            seed_peers: x
+                .seed_peers
+                .iter()
+                .map(|(key, addr)| {
+                    anyhow::Ok((
+                        Text::new(&key.0)
+                            .decode::<node::PublicKey>()
+                            .context("key")?,
+                        net::Host(addr.0.clone()),
+                    ))
+                })
+                .collect::<Result<_, _>>()
+                .context("seed_peers")?,
         })
     }
 }
@@ -109,9 +124,18 @@ pub(super) fn node_key(secrets: &ConsensusSecrets) -> anyhow::Result<Option<node
 pub(super) fn executor(
     cfg: &ConsensusConfig,
     secrets: &ConsensusSecrets,
+    global_config: &consensus_dal::GlobalConfig,
     build_version: Option<semver::Version>,
 ) -> anyhow::Result<executor::Config> {
-    let mut gossip_static_outbound = HashMap::new();
+    // Always connect to seed peers.
+    // Once we implement dynamic peer discovery,
+    // we won't establish a persistent connection to seed peers
+    // but rather just ask them for more peers.
+    let mut gossip_static_outbound: HashMap<_, _> = global_config
+        .seed_peers
+        .iter()
+        .map(|(k, v)| (k.clone(), v.clone()))
+        .collect();
     {
         let mut append = |key: &NodePublicKey, addr: &Host| {
             gossip_static_outbound.insert(

core/node/consensus/src/en.rs

@@ -125,7 +125,7 @@ impl EN {
             ));
 
             let executor = executor::Executor {
-                config: config::executor(&cfg, &secrets, build_version)?,
+                config: config::executor(&cfg, &secrets, &global_config, build_version)?,
                 block_store,
                 batch_store,
                 validator: config::validator_key(&secrets)
@@ -304,6 +304,7 @@ impl EN {
         Ok(consensus_dal::GlobalConfig {
             genesis: zksync_protobuf::serde::deserialize(&genesis.0).context("deserialize()")?,
             registry_address: None,
+            seed_peers: [].into(),
         })
     }
 

core/node/consensus/src/mn.rs

@@ -76,12 +76,12 @@ pub async fn run_main_node(
         s.spawn_bg(run_attestation_controller(
             ctx,
             &pool,
-            global_config,
+            global_config.clone(),
             attestation.clone(),
         ));
 
         let executor = executor::Executor {
-            config: config::executor(&cfg, &secrets, None)?,
+            config: config::executor(&cfg, &secrets, &global_config, None)?,
             block_store,
             batch_store,
             validator: Some(executor::Validator {

core/node/consensus/src/storage/connection.rs

@@ -317,6 +317,7 @@ impl<'a> Connection<'a> {
             }
             .with_hash(),
             registry_address: spec.registry_address,
+            seed_peers: spec.seed_peers.clone(),
         };
 
         txn.try_update_global_config(ctx, &new)

core/node/consensus/src/testonly.rs

@@ -91,11 +91,8 @@ impl ConfigSet {
     }
 }
 
-pub(super) fn new_configs(
-    rng: &mut impl Rng,
-    setup: &Setup,
-    gossip_peers: usize,
-) -> Vec<ConfigSet> {
+pub(super) fn new_configs(rng: &mut impl Rng, setup: &Setup, seed_peers: usize) -> Vec<ConfigSet> {
+    let net_cfgs = network::testonly::new_configs(rng, setup, 0);
     let genesis_spec = config::GenesisSpec {
         chain_id: setup.genesis.chain_id.0.try_into().unwrap(),
         protocol_version: config::ProtocolVersion(setup.genesis.protocol_version.0),
@@ -117,8 +114,17 @@ pub(super) fn new_configs(
             .collect(),
         leader: config::ValidatorPublicKey(setup.validator_keys[0].public().encode()),
         registry_address: None,
+        seed_peers: net_cfgs[..seed_peers]
+            .iter()
+            .map(|c| {
+                (
+                    config::NodePublicKey(c.gossip.key.public().encode()),
+                    config::Host(c.public_addr.0.clone()),
+                )
+            })
+            .collect(),
     };
-    network::testonly::new_configs(rng, setup, gossip_peers)
+    net_cfgs
         .into_iter()
         .enumerate()
         .map(|(i, net)| ConfigSet {