Lockdown Mode Pallet

The Lockdown Mode Pallet is a Substrate module that provides functionality to lock down the runtime execution in a Substrate-based blockchain system. When the lockdown mode is activated, it filters out incoming calls and messages to ensure that only authorized actions are allowed.

Overview

This pallet the governance of the chain to activate or deactivate a lockdown mode. When the lockdown mode is activated, incoming runtime calls and downward messages are filtered based on a preconfigured filter. Additionally, it suspends the execution of XCM (Cross-Consensus Message) messages in the on_idle hook.

The lockdown mode status is stored in the LockdownModeStatus storage item. When the lockdown mode is deactivated, the system resumes normal operations, including the execution of XCM messages in the on_idle hook.

Configuration

This pallet supports configurable traits that allow customization according to specific needs.

Types

• RuntimeEvent: Specifies the runtime event type.
• LockdownModeOrigin: Specifies the origin that is allowed to activate and deactivate the lockdown mode.
• BlackListedCalls: Specifies the filter used to filter incoming runtime calls in lockdown mode.
• LockdownDmpHandler: Specifies the handler for downward messages in lockdown mode.
• XcmExecutorManager: Interface to control the execution of XCMP Queue messages.

Extrinsics

The pallet provides the following extrinsics:

• activate_lockdown_mode: Activates the lockdown mode. Only the specified LockdownModeOrigin can call this extrinsic. It updates the LockdownModeStatus storage item to ACTIVATED (true) and attempts to suspend the execution of XCM messages in the on_idle hook.
• deactivate_lockdown_mode: Deactivates the lockdown mode. Only the specified LockdownModeOrigin can call this extrinsic. It updates the LockdownModeStatus storage item to DEACTIVATED (false) and attempts to resume the execution of XCM messages in the on_idle hook.

Errors

Possible errors returned by the dispatchable calls are:

• LockdownModeAlreadyActivated: The lockdown mode is already activated.
• LockdownModeAlreadyDeactivated: The lockdown mode is already deactivated.

Please note that any failure to suspend or resume XCM execution in the on_idle hook is not treated as a fatal error that stops the function execution. Instead, it is recorded as an event FailedToSuspendIdleXcmExecution or FailedToResumeIdleXcmExecution, respectively, and the function continues its execution.

The lockdown mode can serve as a crucial tool in system maintenance or in case of emergency, when it's necessary to restrict system operation and ensure the system's security and stability.