Select validators for jumpstart DKG

crates/threshold-signature-server/Cargo.toml

@@ -17,6 +17,7 @@ thiserror          ="1.0.63"
 blake2             ="0.10.4"
 x25519-dalek       ={ version="2.0.1", features=["static_secrets"] }
 rand_core          ="0.6.4"
+rand               ="0.8.5"
 zeroize            ="1.8.1"
 hex                ="0.4.3"
 reqwest-eventsource="0.6"

crates/threshold-signature-server/src/user/api.rs

@@ -45,6 +45,8 @@ use futures::{
 };
 use num::{bigint::BigInt, FromPrimitive, Num, ToPrimitive};
 use parity_scale_codec::{Decode, DecodeAll, Encode};
+use rand::{seq::SliceRandom, SeedableRng};
+use rand_core::OsRng;
 use serde::{Deserialize, Serialize};
 use sp_core::{crypto::AccountId32, H256};
 use subxt::{
@@ -55,6 +57,7 @@ use subxt::{
     Config, OnlineClient,
 };
 use synedrion::ThresholdKeyShare;
+use tokio::select;
 use tracing::instrument;
 use x25519_dalek::StaticSecret;
 use zeroize::Zeroize;
@@ -262,7 +265,7 @@ pub async fn generate_network_key(
     State(app_state): State<AppState>,
     encoded_data: Bytes,
 ) -> Result<StatusCode, UserErr> {
-    let data = OcwMessageDkg::decode(&mut encoded_data.as_ref())?;
+    let mut data = OcwMessageDkg::decode(&mut encoded_data.as_ref())?;
     tracing::Span::current().record("block_number", data.block_number);
 
     if data.sig_request_accounts.is_empty() {
@@ -273,8 +276,10 @@ pub async fn generate_network_key(
     let rpc = get_rpc(&app_state.configuration.endpoint).await?;
     let (signer, x25519_secret_key) = get_signer_and_x25519_secret(&app_state.kv_store).await?;
 
+    let selected_validators = get_jumpstart_validators(&api, &rpc, data.block_number).await?;
+
     let in_registration_group =
-        check_in_registration_group(&data.validators_info, signer.account_id());
+        check_in_registration_group(&selected_validators, signer.account_id());
 
     if in_registration_group.is_err() {
         tracing::warn!(
@@ -286,6 +291,8 @@ pub async fn generate_network_key(
         return Ok(StatusCode::MISDIRECTED_REQUEST);
     }
 
+    // Use selected validators rather than the validators from the HTTP request
+    data.validators_info = selected_validators;
     validate_jump_start(&data, &api, &rpc, &app_state.kv_store).await?;
 
     // Do the DKG protocol in another task, so we can already respond
@@ -300,6 +307,55 @@ pub async fn generate_network_key(
     Ok(StatusCode::OK)
 }
 
+/// Deterministically select n initial signers from validator set using block number
+async fn get_jumpstart_validators(
+    api: &OnlineClient<EntropyConfig>,
+    rpc: &LegacyRpcMethods<EntropyConfig>,
+    block_number: u32,
+) -> Result<Vec<entropy_shared::ValidatorInfo>, UserErr> {
+    // Get n from parameters
+    let n = {
+        let total_signers_query = entropy::storage().parameters().signers_info();
+        let signers_info =
+            query_chain(api, rpc, total_signers_query, None).await?.ok_or_else(|| {
+                UserErr::OptionUnwrapError(
+                    "Cannot get signer info from parameters pallet".to_string(),
+                )
+            })?;
+        signers_info.total_signers
+    };
+
+    // Get all validators
+    let all_validators = {
+        let validators_query = entropy::storage().session().validators();
+        query_chain(api, rpc, validators_query, None).await?.ok_or_else(|| {
+            UserErr::OptionUnwrapError("Cannot get validators info from session pallet".to_string())
+        })?
+    };
+
+    // Select n validators
+    let mut rng = rand::rngs::StdRng::seed_from_u64(block_number.into());
+    let selected_validators: Vec<_> =
+        all_validators.choose_multiple(&mut rng, n.into()).cloned().collect();
+
+    // Get validator info for selected validators
+    let mut validators_info: Vec<_> = vec![];
+    for validator_address in selected_validators {
+        let validator_query =
+            entropy::storage().staking_extension().threshold_servers(validator_address);
+        let server_info = query_chain(api, rpc, validator_query, None).await?.ok_or_else(|| {
+            UserErr::OptionUnwrapError("Cannot get server info for selected TS server".to_string())
+        })?;
+        validators_info.push(entropy_shared::ValidatorInfo {
+            x25519_public_key: server_info.x25519_public_key,
+            ip_address: server_info.endpoint,
+            tss_account: server_info.tss_account.0.to_vec(),
+        });
+    }
+
+    Ok(validators_info)
+}
+
 /// Setup and execute DKG.
 ///
 /// Called internally by the [generate_network_key] function.

crates/threshold-signature-server/src/user/tests.rs

@@ -714,11 +714,15 @@ async fn test_jumpstart_network() {
 
     let alice = AccountKeyring::Alice;
 
-    let cxt = test_context_stationary().await;
+    let add_parent_key = false;
     let (_validator_ips, _validator_ids) =
-        spawn_testing_validators(false, ChainSpecType::Development).await;
-    let api = get_api(&cxt.node_proc.ws_url).await.unwrap();
-    let rpc = get_rpc(&cxt.node_proc.ws_url).await.unwrap();
+        spawn_testing_validators(add_parent_key, ChainSpecType::Integration).await;
+
+    let force_authoring = true;
+    let substrate_context = test_node_process_testing_state(force_authoring).await;
+
+    let api = get_api(&substrate_context.ws_url).await.unwrap();
+    let rpc = get_rpc(&substrate_context.ws_url).await.unwrap();
 
     let client = reqwest::Client::new();
 
@@ -753,7 +757,7 @@ async fn test_jumpstart_network() {
 
     // succeeds
     let response_results = join_all(
-        vec![3002, 3003]
+        vec![3002, 3003, 3004]
             .iter()
             .map(|port| {
                 client