Set Existential Deposit to Zero and Refactor Related Tests

ownership-chain/node/src/chain_spec.rs

@@ -1,11 +1,12 @@
 use cumulus_primitives_core::ParaId;
 use fp_evm::GenesisAccount;
 use hex_literal::hex;
-use laos_ownership_runtime::{AccountId, AuraId, Precompiles, EXISTENTIAL_DEPOSIT};
+use laos_ownership_runtime::{AccountId, AuraId, Precompiles};
 use sc_chain_spec::{ChainSpecExtension, ChainSpecGroup};
 use sc_service::ChainType;
 use serde::{Deserialize, Serialize};
 use sp_core::{Pair, Public, H160, U256};
+use sp_runtime::traits::Zero;
 use std::{collections::BTreeMap, str::FromStr};
 
 /// List of endowed accounts.
@@ -181,7 +182,7 @@ fn testnet_genesis(
 		},
 		collator_selection: laos_ownership_runtime::CollatorSelectionConfig {
 			invulnerables: invulnerables.iter().cloned().map(|(acc, _)| acc).collect(),
-			candidacy_bond: EXISTENTIAL_DEPOSIT * 16,
+			candidacy_bond: Zero::zero(),
 			..Default::default()
 		},
 		session: laos_ownership_runtime::SessionConfig {

ownership-chain/runtime/Cargo.toml

@@ -34,7 +34,7 @@ frame-system-rpc-runtime-api = { workspace = true }
 frame-try-runtime = { workspace = true, optional = true }
 pallet-aura = { workspace = true }
 pallet-authorship = { workspace = true }
-pallet-balances = { workspace = true }
+pallet-balances = { workspace = true , features = ["insecure_zero_ed"] }
 pallet-multisig = { workspace = true }
 pallet-session = { workspace = true }
 pallet-sudo = { workspace = true }

ownership-chain/runtime/src/lib.rs

@@ -239,9 +239,6 @@ pub const UNIT: Balance = 1_000_000_000_000_000_000;
 pub const MILLIUNIT: Balance = UNIT / 1000;
 pub const MICROUNIT: Balance = MILLIUNIT / 1000;
 
-/// The existential deposit. Set to 1/10 of the Connected Relay Chain.
-pub const EXISTENTIAL_DEPOSIT: Balance = MILLIUNIT;
-
 /// Current approximation of the gas/s consumption considering
 /// EVM execution over compiled WASM (on 4.4Ghz CPU).
 /// Given the 500ms Weight, from which 75% only are used for transactions,
@@ -333,7 +330,14 @@ impl pallet_authorship::Config for Runtime {
 }
 
 parameter_types! {
-	pub const ExistentialDeposit: Balance = EXISTENTIAL_DEPOSIT;
+	/// The minimum amount required to keep an account open, set to zero in this case.
+	///
+	/// While it's generally advised to have this value greater than zero to avoid potential
+	/// DoS vectors, we set it to zero here due to specific concerns about relay attacks.
+	/// In such attacks, the reset of the nonce upon account deletion can be exploited.
+	/// By setting the ExistentialDeposit to zero, we prevent the scenario where an account's
+	/// balance drops to a level that would trigger its deletion and subsequent nonce reset.
+	pub const ExistentialDeposit: Balance = 0;
 }
 
 impl pallet_balances::Config for Runtime {

ownership-chain/runtime/src/tests.rs

@@ -1,11 +1,29 @@
 use super::*;
-use frame_support::assert_ok;
+use fp_rpc::runtime_decl_for_ethereum_runtime_rpc_api::EthereumRuntimeRPCApiV5;
+use frame_support::{
+	assert_ok,
+	traits::tokens::{fungible::Balanced, Precision},
+};
 use sp_core::U256;
+use std::str::FromStr;
+
+const ALICE: &str = "0xf24FF3a9CF04c71Dbc94D0b566f7A27B94566cac";
+
+// Build genesis storage according to the mock runtime.
+pub fn new_test_ext() -> sp_io::TestExternalities {
+	frame_system::GenesisConfig::<Runtime>::default()
+		.build_storage()
+		.unwrap()
+		.into()
+}
 
 #[test]
-fn test_block_and_gas_limit_constants() {
-	use crate::Runtime;
+fn minimum_balance_should_be_0() {
+	assert_eq!(Balances::minimum_balance(), 0);
+}
 
+#[test]
+fn test_block_and_gas_limit_constants() {
 	let system_block_weights = <Runtime as frame_system::Config>::BlockWeights::get();
 
 	assert_ok!(system_block_weights.clone().validate());
@@ -27,3 +45,17 @@ fn test_multisig_constants() {
 	assert_eq!(<Runtime as pallet_multisig::Config>::DepositFactor::get(), UNIT / 10);
 	assert_eq!(<Runtime as pallet_multisig::Config>::MaxSignatories::get(), 20);
 }
+
+#[test]
+fn send_1_minimum_unit_to_wallet_with_0_wei_balance_should_increase_balance_by_1_wei() {
+	new_test_ext().execute_with(|| {
+		let alice = AccountId::from_str(ALICE).unwrap();
+		assert_eq!(Runtime::account_basic(alice.into()).balance, 0.into());
+
+		let minimum_amount = 1;
+		assert!(Balances::deposit(&alice, minimum_amount, Precision::Exact).is_ok());
+		assert_eq!(Balances::total_balance(&alice), minimum_amount);
+
+		assert_eq!(Runtime::account_basic(alice.into()).balance, 1.into());
+	})
+}