Filter out credit purchase call (#312)

This PR aims to filter out credit purchase calls until the credit system
is implemented. Otherwise, users may have a chance of locking their
funds forever on purchased credits they cannot use.

Closes paritytech/polkadot-sdk#4454

---------

Co-authored-by: Bastian Köcher <[email protected]>

CHANGELOG.md

@@ -21,6 +21,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 - Kusama chains: allow arbitrary XCM execution ([polkadot-fellows/runtimes#261](https://github.com/polkadot-fellows/runtimes/pull/261))
 - Allow everything through XCM SafeCallFilter ([polkadot-fellows/runtimes#285](https://github.com/polkadot-fellows/runtimes/pull/285))
+- Disable Coretime credit purchasing until we have the credit system implemented ([polkadot-fellows/runtimes#312](https://github.com/polkadot-fellows/runtimes/pull/312))
 
 ### Added
 

system-parachains/coretime/coretime-kusama/src/lib.rs

@@ -37,7 +37,8 @@ use frame_support::{
 	genesis_builder_helper::{build_config, create_default_config},
 	parameter_types,
 	traits::{
-		ConstBool, ConstU32, ConstU64, ConstU8, EitherOfDiverse, InstanceFilter, TransformOrigin,
+		ConstBool, ConstU32, ConstU64, ConstU8, Contains, EitherOfDiverse, EverythingBut,
+		InstanceFilter, TransformOrigin,
 	},
 	weights::{ConstantMultiplier, Weight},
 	PalletId,
@@ -170,9 +171,19 @@ parameter_types! {
 	pub const SS58Prefix: u8 = 2;
 }
 
+/// Filter out credit purchase calls until the credit system is implemented. Otherwise, users
+/// may have chance of locking their funds forever on purchased credits they cannot use.
+pub struct IsBrokerCreditPurchaseCall;
+impl Contains<RuntimeCall> for IsBrokerCreditPurchaseCall {
+	fn contains(c: &RuntimeCall) -> bool {
+		matches!(c, RuntimeCall::Broker(pallet_broker::Call::purchase_credit { .. }))
+	}
+}
+
 // Configure FRAME pallets to include in runtime.
 #[derive_impl(frame_system::config_preludes::ParaChainDefaultConfig as frame_system::DefaultConfig)]
 impl frame_system::Config for Runtime {
+	type BaseCallFilter = EverythingBut<IsBrokerCreditPurchaseCall>;
 	/// The identifier used to distinguish between accounts.
 	type AccountId = AccountId;
 	/// The nonce type for storing how many extrinsics an account has signed.