New Pallet: Root offences

Cargo.toml

@@ -132,6 +132,7 @@ members = [
 	"frame/staking/reward-fn",
 	"frame/state-trie-migration",
 	"frame/sudo",
+	"frame/root-offences",
 	"frame/support",
 	"frame/support/procedural",
 	"frame/support/procedural/tools",

frame/nomination-pools/src/lib.rs

@@ -2471,8 +2471,8 @@ impl<T: Config> Pallet<T> {
 impl<T: Config> OnStakerSlash<T::AccountId, BalanceOf<T>> for Pallet<T> {
 	fn on_slash(
 		pool_account: &T::AccountId,
-		// Bonded balance is always read directly from staking, therefore we need not update
-		// anything here.
+		// Bonded balance is always read directly from staking, therefore we
+		// don't need to update anything here.
 		slashed_bonded: BalanceOf<T>,
 		slashed_unlocking: &BTreeMap<EraIndex, BalanceOf<T>>,
 	) {

frame/root-offences/Cargo.toml

@@ -0,0 +1,40 @@
+[package]
+name = "pallet-root-offences"
+version = "1.0.0"
+authors = ["Parity Technologies <[email protected]>"]
+edition = "2021"
+license = "Apache-2.0"
+homepage = "https://substrate.io"
+repository = "https://github.com/paritytech/substrate/"
+description = "FRAME sudo offences pallet"
+
+[package.metadata.docs.rs]
+targets = ["x86_64-unknown-linux-gnu"]
+
+[dependencies]
+codec = { package = "parity-scale-codec", version = "3.0.0", default-features = false, features = ["derive"] }
+scale-info = { version = "2.1.1", default-features = false, features = ["derive"] }
+
+pallet-session = { version = "4.0.0-dev", features = [ "historical" ], path = "../../frame/session", default-features = false }
+pallet-staking = { version = "4.0.0-dev", default-features = false, path = "../../frame/staking" }
+pallet-offences = { version = "4.0.0-dev", default-features = false, path = "../../frame/offences" }
+
+frame-support = { version = "4.0.0-dev", default-features = false, path = "../support" }
+frame-system = { version = "4.0.0-dev", default-features = false, path = "../system" }
+sp-runtime = { version = "6.0.0", path = "../../primitives/runtime" }
+sp-staking = { version = "4.0.0-dev", default-features = false, path = "../../primitives/staking" }
+
+[features]
+runtime-benchmarks = []
+try-runtime = []
+default = ["std"]
+std = [
+	"codec/std",
+	"scale-info/std",
+	"pallet-session/std",
+	"pallet-staking/std",
+	"pallet-offences/std",
+	"frame-support/std",
+    "frame-system/std",
+	"sp-runtime/std",
+]

frame/root-offences/README.md

@@ -0,0 +1,3 @@
+# Sudo Offences Pallet
+
+Pallet that allows the root to create an offence.

frame/root-offences/src/lib.rs

@@ -0,0 +1,110 @@
+// This file is part of Substrate.
+
+// Copyright (C) 2022 Parity Technologies (UK) Ltd.
+// SPDX-License-Identifier: Apache-2.0
+
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//! # Sudo Offences Pallet
+//! Pallet that allows the root to create an offence.
+
+#![cfg_attr(not(feature = "std"), no_std)]
+
+use pallet_session::historical::IdentificationTuple;
+use pallet_staking::{BalanceOf, Exposure, ExposureOf, Pallet as Staking};
+use sp_runtime::{traits::Convert, Perbill};
+use sp_staking::offence::{DisableStrategy, OffenceDetails, OnOffenceHandler};
+
+pub use pallet::*;
+
+#[frame_support::pallet]
+pub mod pallet {
+	use super::*;
+	use frame_support::pallet_prelude::*;
+	use frame_system::pallet_prelude::*;
+
+	#[pallet::config]
+	pub trait Config: frame_system::Config + pallet_staking::Config {
+		type Event: From<Event<Self>> + IsType<<Self as frame_system::Config>::Event>;
+	}
+
+	#[pallet::pallet]
+	#[pallet::generate_store(pub(super) trait Store)]
+	pub struct Pallet<T>(_);
+
+	#[pallet::call]
+	impl<T: Config> Pallet<T>
+	where
+		T: pallet_session::Config<ValidatorId = <T as frame_system::Config>::AccountId>,
+		T: pallet_session::historical::Config<
+			FullIdentification = Exposure<<T as frame_system::Config>::AccountId, BalanceOf<T>>,
+			FullIdentificationOf = ExposureOf<T>,
+		>,
+		T::ValidatorIdOf: Convert<
+			<T as frame_system::Config>::AccountId,
+			Option<<T as frame_system::Config>::AccountId>,
+		>,
+	{
+		/// Allows the `root` to create an offence.
+		#[pallet::weight(10_000)]
+		pub fn create_offence(
+			origin: OriginFor<T>,
+			offenders: Vec<(T::AccountId, Perbill)>,
+		) -> DispatchResult {
+			ensure_root(origin)?;
+
+			let slash_fractions = offenders
+				.clone()
+				.into_iter()
+				.map(|(_, fraction)| fraction)
+				.collect::<Vec<Perbill>>();
+
+			let active_era = Staking::<T>::active_era().ok_or(Error::<T>::FailedToGetActiveEra)?;
+			let now = active_era.index;
+
+			let offender_details: Vec<OffenceDetails<T::AccountId, IdentificationTuple<T>>> =
+				offenders
+					.clone()
+					.into_iter()
+					.map(|(o, _)| OffenceDetails::<T::AccountId, IdentificationTuple<T>> {
+						offender: (o.clone(), Staking::<T>::eras_stakers(now, o)),
+						reporters: vec![],
+					})
+					.collect();
+
+			let session_index = <pallet_session::Pallet<T> as frame_support::traits::ValidatorSet<T::AccountId>>::session_index();
+
+			<pallet_staking::Pallet<T> as OnOffenceHandler<
+				T::AccountId,
+				IdentificationTuple<T>,
+				Weight,
+			>>::on_offence(
+				&offender_details, &slash_fractions, session_index, DisableStrategy::WhenSlashed
+			);
+
+			Self::deposit_event(Event::RootCreatedOffence { offenders });
+			Ok(())
+		}
+	}
+
+	#[pallet::event]
+	#[pallet::generate_deposit(pub(super) fn deposit_event)]
+	pub enum Event<T: Config> {
+		RootCreatedOffence { offenders: Vec<(T::AccountId, Perbill)> },
+	}
+
+	#[pallet::error]
+	pub enum Error<T> {
+		FailedToGetActiveEra,
+	}
+}

frame/system/src/lib.rs

@@ -278,7 +278,8 @@ pub mod pallet {
 			+ Debug
 			+ MaybeDisplay
 			+ Ord
-			+ MaxEncodedLen;
+			+ MaxEncodedLen
+			+ Clone;
 
 		/// Converting trait to take a source type and convert to `AccountId`.
 		///