Rate limit

node/src/chain_spec/crab.rs

@@ -200,6 +200,7 @@ pub fn genesis_config() -> ChainSpec {
 				darwinia_staking: DarwiniaStakingConfig {
 					now: SystemTime::now().duration_since(UNIX_EPOCH).unwrap().as_millis(),
 					elapsed_time: 0,
+					max_unstake_ring: 10_000_000 * UNIT,
 					collator_count: 6,
 					collators: collators
 						.iter()
@@ -303,6 +304,7 @@ fn testnet_genesis(
 		darwinia_staking: DarwiniaStakingConfig {
 			now: SystemTime::now().duration_since(UNIX_EPOCH).unwrap().as_millis(),
 			elapsed_time: 0,
+			max_unstake_ring: 10_000_000 * UNIT,
 			collator_count: collators.len() as _,
 			collators: collators.iter().map(|(a, _)| (a.to_owned(), UNIT)).collect(),
 		},

node/src/chain_spec/darwinia.rs

@@ -196,6 +196,7 @@ pub fn genesis_config() -> ChainSpec {
 				darwinia_staking: DarwiniaStakingConfig {
 					now: SystemTime::now().duration_since(UNIX_EPOCH).unwrap().as_millis(),
 					elapsed_time: 0,
+					max_unstake_ring: 10_000_000 * UNIT,
 					collator_count: 5,
 					collators: collators
 						.iter()
@@ -301,6 +302,7 @@ fn testnet_genesis(
 		darwinia_staking: DarwiniaStakingConfig {
 			now: SystemTime::now().duration_since(UNIX_EPOCH).unwrap().as_millis(),
 			elapsed_time: 0,
+			max_unstake_ring: 10_000_000 * UNIT,
 			collator_count: collators.len() as _,
 			collators: collators.iter().map(|(a, _)| (a.to_owned(), UNIT)).collect(),
 		},

pallet/staking/src/benchmarking.rs

@@ -158,6 +158,15 @@ mod benchmarks {
 		_(RawOrigin::Signed(sender), a);
 	}
 
+	#[benchmark]
+	fn set_max_unstake_ring() {
+		// Worst-case scenario:
+		//
+		// Set max unstake ring successfully.
+		#[extrinsic_call]
+		_(RawOrigin::Root, 1);
+	}
+
 	#[benchmark]
 	fn set_collator_count() {
 		// Worst-case scenario:

pallet/staking/src/lib.rs

@@ -166,8 +166,8 @@ pub mod pallet {
 	pub enum Error<T> {
 		/// Exceed maximum deposit count.
 		ExceedMaxDeposits,
-		/// Exceed maximum unstaking/unbonding count.
-		ExceedMaxUnstakings,
+		/// Exceed maximum unstake amount.
+		ExceedMaxUnstakeAmount,
 		/// Deposit not found.
 		DepositNotFound,
 		/// You are not a staker.
@@ -282,13 +282,29 @@ pub mod pallet {
 	#[pallet::getter(fn elapsed_time)]
 	pub type ElapsedTime<T: Config> = StorageValue<_, Moment, ValueQuery>;
 
+	/// Max unstake RING limit.
+	///
+	/// The maximum RING amount that can be unstaked in a session.
+	#[pallet::storage]
+	#[pallet::getter(fn max_unstake_ring)]
+	pub type MaxUnstakeRing<T: Config> = StorageValue<_, Balance, ValueQuery>;
+
+	/// Unstake accumulator.
+	///
+	/// Tracks the total RING amount being unstaked in a session.
+	#[pallet::storage]
+	#[pallet::getter(fn accumulate_unstake)]
+	pub type AccumulateUnstake<T: Config> = StorageValue<_, Balance, ValueQuery>;
+
 	#[derive(DefaultNoBound)]
 	#[pallet::genesis_config]
 	pub struct GenesisConfig<T: Config> {
 		/// Current timestamp.
 		pub now: Moment,
 		/// The running time of Darwinia1.
 		pub elapsed_time: Moment,
+		/// Max unstake RING limit.
+		pub max_unstake_ring: Balance,
 		/// Genesis collator count.
 		pub collator_count: u32,
 		/// Genesis collator preferences.
@@ -304,6 +320,7 @@ pub mod pallet {
 
 			<SessionStartTime<T>>::put(self.now);
 			<ElapsedTime<T>>::put(self.elapsed_time);
+			<MaxUnstakeRing<T>>::put(self.max_unstake_ring);
 			<CollatorCount<T>>::put(self.collator_count);
 
 			self.collators.iter().for_each(|(who, ring_amount)| {
@@ -400,6 +417,8 @@ pub mod pallet {
 				return Ok(());
 			}
 
+			let mut acc = <AccumulateUnstake<T>>::get().saturating_add(ring_amount);
+
 			<Ledgers<T>>::try_mutate(&who, |l| {
 				let l = l.as_mut().ok_or(<Error<T>>::NotStaker)?;
 
@@ -413,6 +432,8 @@ pub mod pallet {
 				}
 
 				for d in deposits {
+					acc = acc.saturating_add(T::Deposit::amount(&who, d).unwrap_or_default());
+
 					l.deposits.remove(
 						l.deposits
 							.iter()
@@ -426,6 +447,12 @@ pub mod pallet {
 				DispatchResult::Ok(())
 			})?;
 
+			if acc <= <MaxUnstakeRing<T>>::get() {
+				<AccumulateUnstake<T>>::put(acc);
+			} else {
+				Err(<Error<T>>::ExceedMaxUnstakeAmount)?;
+			}
+
 			Self::try_clean_ledger_of(&who);
 
 			Ok(())
@@ -493,6 +520,17 @@ pub mod pallet {
 			Ok(())
 		}
 
+		/// Set max unstake RING limit.
+		#[pallet::call_index(9)]
+		#[pallet::weight(<T as Config>::WeightInfo::set_max_unstake_ring())]
+		pub fn set_max_unstake_ring(origin: OriginFor<T>, amount: Balance) -> DispatchResult {
+			ensure_root(origin)?;
+
+			<MaxUnstakeRing<T>>::put(amount);
+
+			Ok(())
+		}
+
 		/// Set collator count.
 		///
 		/// This will apply to the incoming session.

pallet/staking/src/migration/v2.rs

@@ -2,6 +2,7 @@
 use core::marker::PhantomData;
 // darwinia
 use crate::*;
+use dc_types::UNIT;
 // substrate
 use frame_support::traits::OnRuntimeUpgrade;
 #[cfg(feature = "try-runtime")]
@@ -77,11 +78,12 @@ where
 			return T::DbWeight::get().reads(r);
 		}
 
-		let mut w = 4;
+		let mut w = 5;
 
 		<RingPool<T>>::kill();
 		<KtonPool<T>>::kill();
 		<MigrationStartBlock<T>>::kill();
+		<MaxUnstakeRing<T>>::put(10_000_000 * UNIT);
 		<Ledgers<T>>::translate::<OldLedger<T>, _>(|a, o| {
 			w += 6;
 

pallet/staking/src/mock.rs

@@ -368,6 +368,7 @@ impl ExtBuilder {
 		.assimilate_storage(&mut storage)
 		.unwrap();
 		darwinia_staking::GenesisConfig::<Runtime> {
+			max_unstake_ring: 100 * UNIT,
 			collator_count: self.collator_count,
 			collators: if self.genesis_collator {
 				(1..=self.collator_count).map(|i| (i, UNIT)).collect()

pallet/staking/src/tests.rs

@@ -199,6 +199,7 @@ fn unstake_should_work() {
 
 		// Unstake 1 RING.
 		assert_ok!(Staking::unstake(RuntimeOrigin::signed(1), UNIT, Vec::new()));
+		assert_eq!(Staking::accumulate_unstake(), UNIT);
 		assert_eq!(Balances::free_balance(1), 995 * UNIT);
 		assert_eq!(
 			Staking::ledger_of(1).unwrap(),
@@ -214,6 +215,7 @@ fn unstake_should_work() {
 		// Unstake 1 deposit.
 		Efflux::block(1);
 		assert_ok!(Staking::unstake(RuntimeOrigin::signed(1), 0, vec![1]));
+		assert_eq!(Staking::accumulate_unstake(), 2 * UNIT);
 		assert_eq!(
 			Staking::ledger_of(1).unwrap(),
 			Ledger { ring: 2 * UNIT, deposits: BoundedVec::truncate_from(vec![0, 2]) }
@@ -250,17 +252,58 @@ fn unstake_should_work() {
 		// Unstake 2 RING and 2 deposits.
 		Efflux::block(1);
 		assert_ok!(Staking::unstake(RuntimeOrigin::signed(1), 2 * UNIT, vec![0, 2]));
+		assert_eq!(Staking::accumulate_unstake(), 6 * UNIT);
 		assert!(Staking::ledger_of(1).is_none());
 		assert_eq!(
 			Deposit::deposit_of(1).unwrap(),
 			<BoundedVec<_, <Runtime as darwinia_deposit::Config>::MaxDeposits>>::truncate_from(
 				vec![
-					DepositS { id: 0, value: UNIT, start_time: 3, expired_time: 2635200003, in_use: false },
-					DepositS { id: 1, value: UNIT, start_time: 3, expired_time: 2635200003, in_use: false },
-					DepositS { id: 2, value: UNIT, start_time: 3, expired_time: 2635200003, in_use: false }
+					DepositS {
+						id: 0,
+						value: UNIT,
+						start_time: 3,
+						expired_time: 2635200003,
+						in_use: false
+					},
+					DepositS {
+						id: 1,
+						value: UNIT,
+						start_time: 3,
+						expired_time: 2635200003,
+						in_use: false
+					},
+					DepositS {
+						id: 2,
+						value: UNIT,
+						start_time: 3,
+						expired_time: 2635200003,
+						in_use: false
+					}
 				]
 			)
 		);
+
+		// Prepare rate limit test data.
+		assert_ok!(Deposit::lock(RuntimeOrigin::signed(1), 94 * UNIT + 1, 1));
+		assert_ok!(Staking::stake(RuntimeOrigin::signed(1), 94 * UNIT + 1, vec![3]));
+
+		// Unstake 94 UNIT + 1.
+		assert_noop!(
+			Staking::unstake(RuntimeOrigin::signed(1), 94 * UNIT + 1, Vec::new()),
+			<Error<Runtime>>::ExceedMaxUnstakeAmount
+		);
+
+		// Unstake 94 UNIT + 1.
+		assert_noop!(
+			Staking::unstake(RuntimeOrigin::signed(1), 0, vec![3]),
+			<Error<Runtime>>::ExceedMaxUnstakeAmount
+		);
+
+		// Unstake RING(94 UNIT + 1) and deposit(94 UNIT + 1).
+		assert_noop!(
+			Staking::unstake(RuntimeOrigin::signed(1), 94 * UNIT + 1, vec![3]),
+			<Error<Runtime>>::ExceedMaxUnstakeAmount
+		);
 	});
 }
 

pallet/staking/src/weights.rs

@@ -58,6 +58,7 @@ pub trait WeightInfo {
 	fn nominate() -> Weight;
 	fn chill() -> Weight;
 	fn payout() -> Weight;
+	fn set_max_unstake_ring() -> Weight;
 	fn set_collator_count() -> Weight;
 }
 
@@ -171,6 +172,9 @@ impl<T: frame_system::Config> WeightInfo for SubstrateWeight<T> {
 			.saturating_add(T::DbWeight::get().reads(4_u64))
 			.saturating_add(T::DbWeight::get().writes(1_u64))
 	}
+	fn set_max_unstake_ring() -> Weight {
+		Default::default()
+	}
 	/// Storage: `DarwiniaStaking::CollatorCount` (r:0 w:1)
 	/// Proof: `DarwiniaStaking::CollatorCount` (`max_values`: Some(1), `max_size`: Some(4), added: 499, mode: `MaxEncodedLen`)
 	fn set_collator_count() -> Weight {
@@ -293,6 +297,9 @@ impl WeightInfo for () {
 			.saturating_add(RocksDbWeight::get().reads(4_u64))
 			.saturating_add(RocksDbWeight::get().writes(1_u64))
 	}
+	fn set_max_unstake_ring() -> Weight {
+		Default::default()
+	}
 	/// Storage: `DarwiniaStaking::CollatorCount` (r:0 w:1)
 	/// Proof: `DarwiniaStaking::CollatorCount` (`max_values`: Some(1), `max_size`: Some(4), added: 499, mode: `MaxEncodedLen`)
 	fn set_collator_count() -> Weight {

precompile/staking/src/mock.rs

@@ -268,16 +268,24 @@ impl ExtBuilder {
 	}
 
 	pub(crate) fn build(self) -> sp_io::TestExternalities {
-		let mut t = <frame_system::GenesisConfig<Runtime>>::default()
-			.build_storage()
-			.expect("Frame system builds valid default genesis config");
+		let mut storage =
+			<frame_system::GenesisConfig<Runtime>>::default().build_storage().unwrap();
 
 		pallet_balances::GenesisConfig::<Runtime> { balances: self.balances }
-			.assimilate_storage(&mut t)
-			.expect("Pallet balances storage can be assimilated");
+			.assimilate_storage(&mut storage)
+			.unwrap();
+		darwinia_staking::GenesisConfig::<Runtime> {
+			max_unstake_ring: 500,
+			collator_count: 1,
+			..Default::default()
+		}
+		.assimilate_storage(&mut storage)
+		.unwrap();
+
+		let mut ext = sp_io::TestExternalities::new(storage);
 
-		let mut ext = sp_io::TestExternalities::new(t);
 		ext.execute_with(|| System::set_block_number(1));
+
 		ext
 	}
 }

runtime/crab/src/weights/darwinia_staking.rs

@@ -168,6 +168,9 @@ impl<T: frame_system::Config> darwinia_staking::WeightInfo for WeightInfo<T> {
 			.saturating_add(T::DbWeight::get().reads(4))
 			.saturating_add(T::DbWeight::get().writes(2))
 	}
+	fn set_max_unstake_ring() -> Weight {
+		Default::default()
+	}
 	/// Storage: `DarwiniaStaking::CollatorCount` (r:0 w:1)
 	/// Proof: `DarwiniaStaking::CollatorCount` (`max_values`: Some(1), `max_size`: Some(4), added: 499, mode: `MaxEncodedLen`)
 	fn set_collator_count() -> Weight {

runtime/darwinia/src/weights/darwinia_staking.rs

@@ -168,6 +168,9 @@ impl<T: frame_system::Config> darwinia_staking::WeightInfo for WeightInfo<T> {
 			.saturating_add(T::DbWeight::get().reads(35))
 			.saturating_add(T::DbWeight::get().writes(2))
 	}
+	fn set_max_unstake_ring() -> Weight {
+		Default::default()
+	}
 	/// Storage: `DarwiniaStaking::CollatorCount` (r:0 w:1)
 	/// Proof: `DarwiniaStaking::CollatorCount` (`max_values`: Some(1), `max_size`: Some(4), added: 499, mode: `MaxEncodedLen`)
 	fn set_collator_count() -> Weight {

runtime/pangolin/src/weights/darwinia_staking.rs

@@ -168,6 +168,9 @@ impl<T: frame_system::Config> darwinia_staking::WeightInfo for WeightInfo<T> {
 			.saturating_add(T::DbWeight::get().reads(4))
 			.saturating_add(T::DbWeight::get().writes(2))
 	}
+	fn set_max_unstake_ring() -> Weight {
+		Default::default()
+	}
 	/// Storage: `DarwiniaStaking::CollatorCount` (r:0 w:1)
 	/// Proof: `DarwiniaStaking::CollatorCount` (`max_values`: Some(1), `max_size`: Some(4), added: 499, mode: `MaxEncodedLen`)
 	fn set_collator_count() -> Weight {