Parachains double vote handler initial implementation. (#840)

* Parachains double vote handler initial implementation.

* Make tests test the actual slashing.

* Implement SignedExtension validation of double vote reports.

* Fixes build after merge

* Review fixes

* Adds historical session proofs

* Review fixes.

* Bump runtime spec_version

* Get the session number from the proof

* Check that proof matches session

* Change signature type on DoubleVoteReport

* Adds docs and removes blank lines

* Removes leftover code

* Fix build

* Fix build after a merge

* Apply suggestions from code review

Co-Authored-By: Robert Habermeier <rphmeier@gmail.com>

* Prune ParentToSessionIndex

* Remove a clone and a warning

Co-authored-by: Robert Habermeier <rphmeier@gmail.com>
Co-authored-by: Gavin Wood <gavin@parity.io>

polkadot/Cargo.lock

@@ -4043,6 +4043,7 @@ dependencies = [
  "pallet-authorship 2.0.0-alpha.4 (git+https://github.com/paritytech/substrate)",
  "pallet-babe 2.0.0-alpha.4 (git+https://github.com/paritytech/substrate)",
  "pallet-balances 2.0.0-alpha.4 (git+https://github.com/paritytech/substrate)",
+ "pallet-offences 2.0.0-alpha.4 (git+https://github.com/paritytech/substrate)",
  "pallet-randomness-collective-flip 2.0.0-alpha.4 (git+https://github.com/paritytech/substrate)",
  "pallet-session 2.0.0-alpha.4 (git+https://github.com/paritytech/substrate)",
  "pallet-staking 2.0.0-alpha.4 (git+https://github.com/paritytech/substrate)",
@@ -4154,6 +4155,7 @@ dependencies = [
  "pallet-grandpa 2.0.0-alpha.4 (git+https://github.com/paritytech/substrate)",
  "pallet-indices 2.0.0-alpha.4 (git+https://github.com/paritytech/substrate)",
  "pallet-nicks 2.0.0-alpha.4 (git+https://github.com/paritytech/substrate)",
+ "pallet-offences 2.0.0-alpha.4 (git+https://github.com/paritytech/substrate)",
  "pallet-randomness-collective-flip 2.0.0-alpha.4 (git+https://github.com/paritytech/substrate)",
  "pallet-session 2.0.0-alpha.4 (git+https://github.com/paritytech/substrate)",
  "pallet-staking 2.0.0-alpha.4 (git+https://github.com/paritytech/substrate)",

polkadot/primitives/src/parachain.rs

@@ -580,7 +580,7 @@ pub struct Activity(#[cfg_attr(feature = "std", serde(with="bytes"))] pub Vec<u8
 
 /// Statements that can be made about parachain candidates. These are the
 /// actual values that are signed.
-#[derive(Clone, PartialEq, Eq, Encode)]
+#[derive(Clone, PartialEq, Eq, Encode, Decode)]
 #[cfg_attr(feature = "std", derive(Debug))]
 pub enum Statement {
 	/// Proposal of a parachain candidate.
@@ -596,8 +596,7 @@ pub enum Statement {
 
 /// An either implicit or explicit attestation to the validity of a parachain
 /// candidate.
-#[derive(Clone, PartialEq, Decode, Encode)]
+#[derive(Clone, Eq, PartialEq, Decode, Encode, RuntimeDebug)]
-#[cfg_attr(feature = "std", derive(Debug))]
 pub enum ValidityAttestation {
 	/// Implicit validity attestation by issuing.
 	/// This corresponds to issuance of a `Candidate` statement.

polkadot/runtime/common/Cargo.toml

@@ -28,6 +28,7 @@ staking = { package = "pallet-staking", git = "https://github.com/paritytech/sub
 system = { package = "frame-system", git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
 timestamp = { package = "pallet-timestamp", git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
 vesting = { package = "pallet-vesting", git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
+offences = { package = "pallet-offences", git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
 frame-benchmarking = { git = "https://github.com/paritytech/substrate", branch = "master", default-features = false, optional = true }
 
 primitives = { package = "polkadot-primitives", path = "../../primitives", default-features = false }

polkadot/runtime/common/src/registrar.rs

@@ -312,7 +312,7 @@ decl_module! {
 		) {
 			let who = ensure_signed(origin)?;
 
-			T::Currency::reserve(&who, T::ParathreadDeposit::get())?;
+			<T as Trait>::Currency::reserve(&who, T::ParathreadDeposit::get())?;
 
 			let info = ParaInfo {
 				scheduling: Scheduling::Dynamic,
@@ -371,7 +371,7 @@ decl_module! {
 			Self::force_unschedule(|i| i == id);
 
 			let debtor = <Debtors<T>>::take(id);
-			let _ = T::Currency::unreserve(&debtor, T::ParathreadDeposit::get());
+			let _ = <T as Trait>::Currency::unreserve(&debtor, T::ParathreadDeposit::get());
 
 			Self::deposit_event(Event::ParathreadRegistered(id));
 		}
@@ -646,7 +646,7 @@ mod tests {
 		traits::{
 			BlakeTwo256, IdentityLookup, OnInitialize, OnFinalize, Dispatchable,
 			AccountIdConversion,
-		}, testing::{UintAuthorityId, Header}, Perbill
+		}, testing::{UintAuthorityId, Header}, KeyTypeId, Perbill, curve::PiecewiseLinear,
 	};
 	use primitives::{
 		parachain::{
@@ -657,6 +657,7 @@ mod tests {
 		Balance, BlockNumber,
 	};
 	use frame_support::{
+		traits::KeyOwnerProofSystem,
 		impl_outer_origin, impl_outer_dispatch, assert_ok, parameter_types, assert_noop,
 	};
 	use keyring::Sr25519Keyring;
@@ -678,6 +679,17 @@ mod tests {
 		}
 	}
 
+	pallet_staking_reward_curve::build! {
+		const REWARD_CURVE: PiecewiseLinear<'static> = curve!(
+			min_inflation: 0_025_000,
+			max_inflation: 0_100_000,
+			ideal_stake: 0_500_000,
+			falloff: 0_050_000,
+			max_piece_count: 40,
+			test_precision: 0_005_000,
+		);
+	}
+
 	#[derive(Clone, Eq, PartialEq)]
 	pub struct Test;
 	parameter_types! {
@@ -735,7 +747,12 @@ mod tests {
 	}
 
 	parameter_types!{
+		pub const SlashDeferDuration: staking::EraIndex = 7;
 		pub const AttestationPeriod: BlockNumber = 100;
+		pub const MinimumPeriod: u64 = 3;
+		pub const SessionsPerEra: sp_staking::SessionIndex = 6;
+		pub const BondingDuration: staking::EraIndex = 28;
+		pub const MaxNominatorRewardedPerValidator: u32 = 64;
 	}
 
 	impl attestations::Trait for Test {
@@ -748,6 +765,7 @@ mod tests {
 		pub const Period: BlockNumber = 1;
 		pub const Offset: BlockNumber = 0;
 		pub const DisabledValidatorsThreshold: Perbill = Perbill::from_percent(17);
+		pub const RewardCurve: &'static PiecewiseLinear<'static> = &REWARD_CURVE;
 	}
 
 	impl session::Trait for Test {
@@ -766,6 +784,34 @@ mod tests {
 		pub const MaxCodeSize: u32 = 100;
 	}
 
+	impl staking::Trait for Test {
+		type RewardRemainder = ();
+		type CurrencyToVote = ();
+		type Event = ();
+		type Currency = balances::Module<Test>;
+		type Slash = ();
+		type Reward = ();
+		type SessionsPerEra = SessionsPerEra;
+		type BondingDuration = BondingDuration;
+		type SlashDeferDuration = SlashDeferDuration;
+		type SlashCancelOrigin = system::EnsureRoot<Self::AccountId>;
+		type SessionInterface = Self;
+		type Time = timestamp::Module<Test>;
+		type RewardCurve = RewardCurve;
+		type MaxNominatorRewardedPerValidator = MaxNominatorRewardedPerValidator;
+	}
+
+	impl timestamp::Trait for Test {
+		type Moment = u64;
+		type OnTimestampSet = ();
+		type MinimumPeriod = MinimumPeriod;
+	}
+
+	impl session::historical::Trait for Test {
+		type FullIdentification = staking::Exposure<u64, Balance>;
+		type FullIdentificationOf = staking::ExposureOf<Self>;
+	}
+
 	impl parachains::Trait for Test {
 		type Origin = Origin;
 		type Call = Call;
@@ -775,6 +821,10 @@ mod tests {
 		type Randomness = RandomnessCollectiveFlip;
 		type MaxCodeSize = MaxCodeSize;
 		type MaxHeadDataSize = MaxHeadDataSize;
+		type Proof = session::historical::Proof;
+		type KeyOwnerProofSystem = session::historical::Module<Test>;
+		type IdentificationTuple = <Self::KeyOwnerProofSystem as KeyOwnerProofSystem<(KeyTypeId, Vec<u8>)>>::IdentificationTuple;
+		type ReportOffence = ();
 	}
 
 	parameter_types! {

polkadot/runtime/kusama/src/lib.rs

@@ -34,7 +34,7 @@ use runtime_common::{attestations, claims, parachains, registrar, slots,
 };
 use sp_runtime::{
 	create_runtime_str, generic, impl_opaque_keys,
-	ApplyExtrinsicResult, Percent, Permill, Perbill, RuntimeDebug,
+	ApplyExtrinsicResult, KeyTypeId, Percent, Permill, Perbill, RuntimeDebug,
 	transaction_validity::{TransactionValidity, InvalidTransaction, TransactionValidityError},
 	curve::PiecewiseLinear,
 	traits::{BlakeTwo256, Block as BlockT, SignedExtension, OpaqueKeys, ConvertInto, IdentityLookup},
@@ -48,13 +48,14 @@ use version::NativeVersion;
 use sp_core::OpaqueMetadata;
 use sp_staking::SessionIndex;
 use frame_support::{
-	parameter_types, construct_runtime, traits::{SplitTwoWays, Randomness},
+	parameter_types, construct_runtime, traits::{KeyOwnerProofSystem, SplitTwoWays, Randomness},
 	weights::DispatchInfo,
 };
 use im_online::sr25519::AuthorityId as ImOnlineId;
 use authority_discovery_primitives::AuthorityId as AuthorityDiscoveryId;
 use system::offchain::TransactionSubmitter;
 use pallet_transaction_payment_rpc_runtime_api::RuntimeDispatchInfo;
+use session::{historical as session_historical};
 
 #[cfg(feature = "std")]
 pub use staking::StakerStatus;
@@ -491,6 +492,10 @@ impl parachains::Trait for Runtime {
 	type Registrar = Registrar;
 	type MaxCodeSize = MaxCodeSize;
 	type MaxHeadDataSize = MaxHeadDataSize;
+	type Proof = session::historical::Proof;
+	type KeyOwnerProofSystem = session::historical::Module<Self>;
+	type IdentificationTuple = <Self::KeyOwnerProofSystem as KeyOwnerProofSystem<(KeyTypeId, Vec<u8>)>>::IdentificationTuple;
+	type ReportOffence = Offences;
 }
 
 parameter_types! {
@@ -648,6 +653,7 @@ construct_runtime! {
 		Authorship: authorship::{Module, Call, Storage},
 		Staking: staking::{Module, Call, Storage, Config<T>, Event<T>},
 		Offences: offences::{Module, Call, Storage, Event},
+		Historical: session_historical::{Module},
 		Session: session::{Module, Call, Storage, Event, Config<T>},
 		FinalityTracker: finality_tracker::{Module, Call, Storage, Inherent},
 		Grandpa: grandpa::{Module, Call, Storage, Config, Event},
@@ -708,7 +714,8 @@ pub type SignedExtra = (
 	system::CheckNonce<Runtime>,
 	system::CheckWeight<Runtime>,
 	transaction_payment::ChargeTransactionPayment::<Runtime>,
-	registrar::LimitParathreadCommits<Runtime>
+	registrar::LimitParathreadCommits<Runtime>,
+	parachains::ValidateDoubleVoteReports<Runtime>,
 );
 /// Unchecked extrinsic type as expected by this runtime.
 pub type UncheckedExtrinsic = generic::UncheckedExtrinsic<Address, Call, Signature, SignedExtra>;

polkadot/runtime/polkadot/src/lib.rs

@@ -35,7 +35,7 @@ use primitives::{
 };
 use sp_runtime::{
 	create_runtime_str, generic, impl_opaque_keys,
-	ApplyExtrinsicResult, Percent, Permill, Perbill, RuntimeDebug,
+	ApplyExtrinsicResult, KeyTypeId, Percent, Permill, Perbill, RuntimeDebug,
 	transaction_validity::{TransactionValidity, InvalidTransaction, TransactionValidityError},
 	curve::PiecewiseLinear,
 	traits::{
@@ -52,13 +52,14 @@ use version::NativeVersion;
 use sp_core::OpaqueMetadata;
 use sp_staking::SessionIndex;
 use frame_support::{
-	parameter_types, construct_runtime, traits::{SplitTwoWays, Randomness},
+	parameter_types, construct_runtime, traits::{KeyOwnerProofSystem, SplitTwoWays, Randomness},
 	weights::DispatchInfo,
 };
 use im_online::sr25519::AuthorityId as ImOnlineId;
 use authority_discovery_primitives::AuthorityId as AuthorityDiscoveryId;
 use system::offchain::TransactionSubmitter;
 use pallet_transaction_payment_rpc_runtime_api::RuntimeDispatchInfo;
+use session::{historical as session_historical};
 
 #[cfg(feature = "std")]
 pub use staking::StakerStatus;
@@ -499,6 +500,10 @@ impl parachains::Trait for Runtime {
 	type Registrar = Registrar;
 	type MaxCodeSize = MaxCodeSize;
 	type MaxHeadDataSize = MaxHeadDataSize;
+	type Proof = session::historical::Proof;
+	type KeyOwnerProofSystem = session::historical::Module<Self>;
+	type IdentificationTuple = <Self::KeyOwnerProofSystem as KeyOwnerProofSystem<(KeyTypeId, Vec<u8>)>>::IdentificationTuple;
+	type ReportOffence = Offences;
 }
 
 parameter_types! {
@@ -579,6 +584,7 @@ construct_runtime! {
 		Authorship: authorship::{Module, Call, Storage},
 		Staking: staking::{Module, Call, Storage, Config<T>, Event<T>},
 		Offences: offences::{Module, Call, Storage, Event},
+		Historical: session_historical::{Module},
 		Session: session::{Module, Call, Storage, Event, Config<T>},
 		FinalityTracker: finality_tracker::{Module, Call, Storage, Inherent},
 		Grandpa: grandpa::{Module, Call, Storage, Config, Event},
@@ -630,7 +636,8 @@ pub type SignedExtra = (
 	system::CheckNonce<Runtime>,
 	system::CheckWeight<Runtime>,
 	transaction_payment::ChargeTransactionPayment::<Runtime>,
-	registrar::LimitParathreadCommits<Runtime>
+	registrar::LimitParathreadCommits<Runtime>,
+	parachains::ValidateDoubleVoteReports<Runtime>
 );
 /// Unchecked extrinsic type as expected by this runtime.
 pub type UncheckedExtrinsic = generic::UncheckedExtrinsic<Address, Call, Signature, SignedExtra>;

polkadot/runtime/test-runtime/Cargo.toml

@@ -36,6 +36,7 @@ finality-tracker = { package = "pallet-finality-tracker", git = "https://github.
 grandpa = { package = "pallet-grandpa", git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
 indices = { package = "pallet-indices", git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
 nicks = { package = "pallet-nicks", git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
+offences = { package = "pallet-offences", git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
 randomness-collective-flip = { package = "pallet-randomness-collective-flip", git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
 session = { package = "pallet-session", git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
 frame-support = { git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
@@ -89,6 +90,7 @@ std = [
 	"grandpa/std",
 	"indices/std",
 	"nicks/std",
+	"offences/std",
 	"sp-runtime/std",
 	"sp-staking/std",
 	"session/std",

polkadot/runtime/test-runtime/src/lib.rs

@@ -34,7 +34,7 @@ use runtime_common::{attestations, claims, parachains, registrar, slots,
 
 use sp_runtime::{
 	create_runtime_str, generic, impl_opaque_keys,
-	ApplyExtrinsicResult, Perbill, RuntimeDebug,
+	ApplyExtrinsicResult, Perbill, RuntimeDebug, KeyTypeId,
 	transaction_validity::{TransactionValidity, InvalidTransaction, TransactionValidityError},
 	curve::PiecewiseLinear,
 	traits::{BlakeTwo256, Block as BlockT, StaticLookup, SignedExtension, OpaqueKeys, ConvertInto},
@@ -46,10 +46,12 @@ use version::NativeVersion;
 use sp_core::OpaqueMetadata;
 use sp_staking::SessionIndex;
 use frame_support::{
-	parameter_types, construct_runtime, traits::Randomness,
+	parameter_types, construct_runtime,
+	traits::{KeyOwnerProofSystem, Randomness},
 	weights::DispatchInfo,
 };
 use pallet_transaction_payment_rpc_runtime_api::RuntimeDispatchInfo;
+use session::{historical as session_historical};
 
 #[cfg(feature = "std")]
 pub use staking::StakerStatus;
@@ -311,6 +313,18 @@ impl parachains::Trait for Runtime {
 	type Registrar = Registrar;
 	type MaxCodeSize = MaxCodeSize;
 	type MaxHeadDataSize = MaxHeadDataSize;
+	type Proof = session::historical::Proof;
+	type KeyOwnerProofSystem = session::historical::Module<Self>;
+	type IdentificationTuple = <
+			Self::KeyOwnerProofSystem as KeyOwnerProofSystem<(KeyTypeId, Vec<u8>)>
+		>::IdentificationTuple;
+	type ReportOffence = Offences;
+}
+
+impl offences::Trait for Runtime {
+	type Event = Event;
+	type IdentificationTuple = session::historical::IdentificationTuple<Self>;
+	type OnOffenceHandler = Staking;
 }
 
 parameter_types! {
@@ -385,6 +399,8 @@ construct_runtime! {
 		// Consensus support.
 		Authorship: authorship::{Module, Call, Storage},
 		Staking: staking::{Module, Call, Storage, Config<T>, Event<T>},
+		Offences: offences::{Module, Call, Storage, Event},
+		Historical: session_historical::{Module},
 		Session: session::{Module, Call, Storage, Event, Config<T>},
 		Grandpa: grandpa::{Module, Call, Storage, Config, Event},