standards: add proxy and timelock primitives

Author: HDauven

Makefile

@@ -1,4 +1,4 @@
-STANDARDS_EXAMPLES := standards/examples/drc20_roles_pausable standards/examples/drc721_collection standards/examples/multisig_controller
+STANDARDS_EXAMPLES := standards/examples/drc20_roles_pausable standards/examples/drc721_collection standards/examples/multisig_controller standards/examples/proxy_counter
 STANDARDS_WASM_CONTRACTS := $(STANDARDS_EXAMPLES)
 LEGACY_SUBDIRS := tests/alice tests/bob tests/charlie genesis/transfer genesis/stake tests/host_fn
 STANDARDS_PROPTEST_CASES ?= 8192

standards/Cargo.lock

@@ -4,6 +4,7 @@ members = [
     "examples/drc20_roles_pausable",
     "examples/drc721_collection",
     "examples/multisig_controller",
+    "examples/proxy_counter",
 ]
 
 resolver = "2"

standards/Cargo.toml

@@ -14,6 +14,7 @@ pub const ZERO_PRINCIPAL: &str = "DuskStandards: zero principal";
 pub const REPLAY: &str = "DuskStandards: replay";
 pub const INVALID_NONCE: &str = "DuskStandards: invalid nonce";
 pub const DELAY_NOT_ELAPSED: &str = "DuskStandards: delay not elapsed";
+pub const OPERATION_DONE: &str = "DuskStandards: operation already done";
 pub const OPERATION_UNKNOWN: &str = "DuskStandards: operation unknown";
 pub const INVALID_OPERATION: &str = "DuskStandards: invalid operation";
 pub const EXPIRED: &str = "DuskStandards: expired";

standards/dusk-contract-standards/src/core/error.rs

@@ -0,0 +1,200 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+//
+// Copyright (c) DUSK NETWORK. All rights reserved.
+
+//! Role-gated timelock controller.
+
+use alloc::vec::Vec;
+
+use crate::access::{AccessControl, Role};
+use crate::core::{error, Principal};
+use crate::governance::{OperationId, ScheduledOperation, Timelock};
+
+/// Role allowed to update timelock policy.
+pub const TIMELOCK_ADMIN_ROLE: Role = {
+    let mut role = [0u8; 32];
+    role[0] = 1;
+    role
+};
+
+/// Role allowed to schedule operations.
+pub const PROPOSER_ROLE: Role = {
+    let mut role = [0u8; 32];
+    role[0] = 2;
+    role
+};
+
+/// Role allowed to execute ready operations.
+pub const EXECUTOR_ROLE: Role = {
+    let mut role = [0u8; 32];
+    role[0] = 3;
+    role
+};
+
+/// Role allowed to cancel pending operations.
+pub const CANCELLER_ROLE: Role = {
+    let mut role = [0u8; 32];
+    role[0] = 4;
+    role
+};
+
+/// Timelock plus role-based caller policy.
+#[derive(Clone, Debug)]
+pub struct TimelockController {
+    access: AccessControl,
+    timelock: Timelock,
+    self_principal: Principal,
+}
+
+impl TimelockController {
+    /// Creates a controller and grants all controller roles to `admin`.
+    pub fn new(
+        self_principal: Principal,
+        admin: Principal,
+        min_delay: u64,
+    ) -> Self {
+        if self_principal.is_zero() || admin.is_zero() {
+            panic!("{}", error::ZERO_PRINCIPAL);
+        }
+        let mut access = AccessControl::new();
+        access.init_admin(admin);
+        access.grant_role(admin, TIMELOCK_ADMIN_ROLE, admin);
+        access.grant_role(admin, PROPOSER_ROLE, admin);
+        access.grant_role(admin, EXECUTOR_ROLE, admin);
+        access.grant_role(admin, CANCELLER_ROLE, admin);
+        Self {
+            access,
+            timelock: Timelock::new(min_delay),
+            self_principal,
+        }
+    }
+
+    /// Returns the controller principal used for self-governed operations.
+    pub const fn self_principal(&self) -> Principal {
+        self.self_principal
+    }
+
+    /// Returns access-control state.
+    pub const fn access(&self) -> &AccessControl {
+        &self.access
+    }
+
+    /// Returns timelock state.
+    pub const fn timelock(&self) -> &Timelock {
+        &self.timelock
+    }
+
+    /// Returns a scheduled operation.
+    pub fn get(&self, id: OperationId) -> Option<&ScheduledOperation> {
+        self.timelock.get(id)
+    }
+
+    /// Returns whether an account has a role.
+    pub fn has_role(&self, role: Role, account: Principal) -> bool {
+        self.access.has_role(role, account)
+    }
+
+    /// Grants a role through the underlying access-control policy.
+    pub fn grant_role(
+        &mut self,
+        caller: Principal,
+        role: Role,
+        account: Principal,
+    ) {
+        self.access.grant_role(caller, role, account);
+    }
+
+    /// Revokes a role through the underlying access-control policy.
+    pub fn revoke_role(
+        &mut self,
+        caller: Principal,
+        role: Role,
+        account: Principal,
+    ) {
+        self.access.revoke_role(caller, role, account);
+    }
+
+    /// Updates the minimum delay. Caller must be the controller itself.
+    ///
+    /// Composing contracts should reach this path through a scheduled
+    /// operation, not through an arbitrary administrator call.
+    pub fn set_min_delay(&mut self, caller: Principal, min_delay: u64) {
+        if caller != self.self_principal {
+            panic!("{}", error::UNAUTHORIZED);
+        }
+        self.timelock.set_min_delay(min_delay);
+    }
+
+    /// Schedules a self-governed minimum-delay update.
+    pub fn schedule_min_delay_change(
+        &mut self,
+        caller: Principal,
+        id: OperationId,
+        now: u64,
+        min_delay: u64,
+    ) -> u64 {
+        self.access.assert_role(PROPOSER_ROLE, caller);
+        self.timelock
+            .schedule(id, now, min_delay.to_be_bytes().to_vec())
+    }
+
+    /// Executes a ready minimum-delay update as the controller itself.
+    pub fn execute_min_delay_change(
+        &mut self,
+        caller: Principal,
+        id: OperationId,
+        now: u64,
+    ) -> u64 {
+        self.access.assert_role(EXECUTOR_ROLE, caller);
+        let op = self
+            .timelock
+            .get(id)
+            .unwrap_or_else(|| panic!("{}", error::OPERATION_UNKNOWN));
+        if op.done {
+            panic!("{}", error::OPERATION_DONE);
+        }
+        if now < op.ready_at {
+            panic!("{}", error::DELAY_NOT_ELAPSED);
+        }
+        let bytes: [u8; 8] = op
+            .payload
+            .as_slice()
+            .try_into()
+            .unwrap_or_else(|_| panic!("{}", error::INVALID_OPERATION));
+        let min_delay = u64::from_be_bytes(bytes);
+        self.timelock.execute(id, now);
+        self.set_min_delay(self.self_principal, min_delay);
+        min_delay
+    }
+
+    /// Schedules an operation. Caller must have proposer role.
+    pub fn schedule(
+        &mut self,
+        caller: Principal,
+        id: OperationId,
+        now: u64,
+        payload: Vec<u8>,
+    ) -> u64 {
+        self.access.assert_role(PROPOSER_ROLE, caller);
+        self.timelock.schedule(id, now, payload)
+    }
+
+    /// Cancels a pending operation. Caller must have canceller role.
+    pub fn cancel(&mut self, caller: Principal, id: OperationId) {
+        self.access.assert_role(CANCELLER_ROLE, caller);
+        self.timelock.cancel(id);
+    }
+
+    /// Executes a ready operation. Caller must have executor role.
+    pub fn execute(
+        &mut self,
+        caller: Principal,
+        id: OperationId,
+        now: u64,
+    ) -> Vec<u8> {
+        self.access.assert_role(EXECUTOR_ROLE, caller);
+        self.timelock.execute(id, now)
+    }
+}