1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
// This file is part of Substrate.

// Copyright (C) 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.

//! > Made with *Substrate*, for *Polkadot*.
//!
//! [![github]](https://github.com/paritytech/polkadot-sdk/tree/master/substrate/frame/sudo)
//! [![polkadot]](https://polkadot.network)
//!
//! [github]: https://img.shields.io/badge/github-8da0cb?style=for-the-badge&labelColor=555555&logo=github
//! [polkadot]: https://img.shields.io/badge/polkadot-E6007A?style=for-the-badge&logo=polkadot&logoColor=white
//!
//! # Sudo Pallet
//!
//! A pallet to provide a way to execute privileged runtime calls using a specified sudo ("superuser
//! do") account.
//!
//! ## Pallet API
//!
//! See the [`pallet`] module for more information about the interfaces this pallet exposes,
//! including its configuration trait, dispatchables, storage items, events and errors.
//!
//! ## Overview
//!
//! In Substrate blockchains, pallets may contain dispatchable calls that can only be called at
//! the system level of the chain (i.e. dispatchables that require a `Root` origin).
//! Setting a privileged account, called the _sudo key_, allows you to make such calls as an
//! extrinsic.
//!
//! Here's an example of a privileged function in another pallet:
//!
//! ```
//! #[frame_support::pallet]
//! pub mod pallet {
//! 	use super::*;
//! 	use frame_support::pallet_prelude::*;
//! 	use frame_system::pallet_prelude::*;
//!
//! 	#[pallet::pallet]
//! 	pub struct Pallet<T>(_);
//!
//! 	#[pallet::config]
//! 	pub trait Config: frame_system::Config {}
//!
//! 	#[pallet::call]
//! 	impl<T: Config> Pallet<T> {
//! 		#[pallet::weight(0)]
//!         pub fn privileged_function(origin: OriginFor<T>) -> DispatchResult {
//!             ensure_root(origin)?;
//!
//!             // do something...
//!
//!             Ok(())
//!         }
//! 	}
//! }
//! ```
//!
//! With the Sudo pallet configured in your chain's runtime you can execute this privileged
//! function by constructing a call using the [`sudo`](Pallet::sudo) dispatchable.
//!
//! To use this pallet in your runtime, a sudo key must be specified in the [`GenesisConfig`] of
//! the pallet. You can change this key at anytime once your chain is live using the
//! [`set_key`](Pallet::set_key) dispatchable, however <strong>only one sudo key can be set at a
//! time</strong>. The pallet also allows you to make a call using
//! [`sudo_unchecked_weight`](Pallet::sudo_unchecked_weight), which allows the sudo account to
//! execute a call with a custom weight.
//!
//! <div class="example-wrap" style="display:inline-block"><pre class="compile_fail"
//! style="white-space:normal;font:inherit;">
//! <strong>Note:</strong> this pallet is not meant to be used inside other pallets. It is only
//! meant to be used by constructing runtime calls from outside the runtime.
//! </pre></div>
//!
//! This pallet also defines a [`SignedExtension`](sp_runtime::traits::SignedExtension) called
//! [`CheckOnlySudoAccount`] to ensure that only signed transactions by the sudo account are
//! accepted by the transaction pool. The intended use of this signed extension is to prevent other
//! accounts from spamming the transaction pool for the initial phase of a chain, during which
//! developers may only want a sudo account to be able to make transactions.
//!
//! Learn more about the `Root` origin in the [`RawOrigin`](frame_system::RawOrigin) type
//! documentation.
//!
//! ### Examples
//!
//! 1. You can make a privileged runtime call using `sudo` with an account that matches the sudo
//!    key.
#![doc = docify::embed!("src/tests.rs", sudo_basics)]
//!
//! 2. Only an existing sudo key can set a new one.
#![doc = docify::embed!("src/tests.rs", set_key_basics)]
//!
//! 3. You can also make non-privileged calls using `sudo_as`.
#![doc = docify::embed!("src/tests.rs", sudo_as_emits_events_correctly)]
//!
//! ## Low Level / Implementation Details
//!
//! This pallet checks that the caller of its dispatchables is a signed account and ensures that the
//! caller matches the sudo key in storage.
//! A caller of this pallet's dispatchables does not pay any fees to dispatch a call. If the account
//! making one of these calls is not the sudo key, the pallet returns a [`Error::RequireSudo`]
//! error.
//!
//! Once an origin is verified, sudo calls use `dispatch_bypass_filter` from the
//! [`UnfilteredDispatchable`](frame_support::traits::UnfilteredDispatchable) trait to allow call
//! execution without enforcing any further origin checks.

#![deny(missing_docs)]
#![cfg_attr(not(feature = "std"), no_std)]

use sp_runtime::{traits::StaticLookup, DispatchResult};
use sp_std::prelude::*;

use frame_support::{dispatch::GetDispatchInfo, traits::UnfilteredDispatchable};

mod extension;
#[cfg(test)]
mod mock;
#[cfg(test)]
mod tests;

#[cfg(feature = "runtime-benchmarks")]
mod benchmarking;
pub mod weights;
pub use weights::WeightInfo;

pub use extension::CheckOnlySudoAccount;
pub use pallet::*;

type AccountIdLookupOf<T> = <<T as frame_system::Config>::Lookup as StaticLookup>::Source;

#[frame_support::pallet]
pub mod pallet {
	use super::{DispatchResult, *};
	use frame_support::pallet_prelude::*;
	use frame_system::{pallet_prelude::*, RawOrigin};

	/// Default preludes for [`Config`].
	pub mod config_preludes {
		use super::*;
		use frame_support::derive_impl;

		/// Default prelude sensible to be used in a testing environment.
		pub struct TestDefaultConfig;

		#[derive_impl(frame_system::config_preludes::TestDefaultConfig, no_aggregated_types)]
		impl frame_system::DefaultConfig for TestDefaultConfig {}

		#[frame_support::register_default_impl(TestDefaultConfig)]
		impl DefaultConfig for TestDefaultConfig {
			type WeightInfo = ();
			#[inject_runtime_type]
			type RuntimeEvent = ();
			#[inject_runtime_type]
			type RuntimeCall = ();
		}
	}
	#[pallet::config(with_default)]
	pub trait Config: frame_system::Config {
		/// The overarching event type.
		#[pallet::no_default_bounds]
		type RuntimeEvent: From<Event<Self>> + IsType<<Self as frame_system::Config>::RuntimeEvent>;

		/// A sudo-able call.
		#[pallet::no_default_bounds]
		type RuntimeCall: Parameter
			+ UnfilteredDispatchable<RuntimeOrigin = Self::RuntimeOrigin>
			+ GetDispatchInfo;

		/// Type representing the weight of this pallet
		type WeightInfo: WeightInfo;
	}

	#[pallet::pallet]
	pub struct Pallet<T>(_);

	#[pallet::call]
	impl<T: Config> Pallet<T> {
		/// Authenticates the sudo key and dispatches a function call with `Root` origin.
		#[pallet::call_index(0)]
		#[pallet::weight({
			let dispatch_info = call.get_dispatch_info();
			(
				T::WeightInfo::sudo().saturating_add(dispatch_info.weight),
				dispatch_info.class
			)
		})]
		pub fn sudo(
			origin: OriginFor<T>,
			call: Box<<T as Config>::RuntimeCall>,
		) -> DispatchResultWithPostInfo {
			Self::ensure_sudo(origin)?;

			let res = call.dispatch_bypass_filter(RawOrigin::Root.into());
			Self::deposit_event(Event::Sudid { sudo_result: res.map(|_| ()).map_err(|e| e.error) });

			// Sudo user does not pay a fee.
			Ok(Pays::No.into())
		}

		/// Authenticates the sudo key and dispatches a function call with `Root` origin.
		/// This function does not check the weight of the call, and instead allows the
		/// Sudo user to specify the weight of the call.
		///
		/// The dispatch origin for this call must be _Signed_.
		#[pallet::call_index(1)]
		#[pallet::weight((*weight, call.get_dispatch_info().class))]
		pub fn sudo_unchecked_weight(
			origin: OriginFor<T>,
			call: Box<<T as Config>::RuntimeCall>,
			weight: Weight,
		) -> DispatchResultWithPostInfo {
			Self::ensure_sudo(origin)?;
			let _ = weight; // We don't check the weight witness since it is a root call.

			let res = call.dispatch_bypass_filter(RawOrigin::Root.into());
			Self::deposit_event(Event::Sudid { sudo_result: res.map(|_| ()).map_err(|e| e.error) });

			// Sudo user does not pay a fee.
			Ok(Pays::No.into())
		}

		/// Authenticates the current sudo key and sets the given AccountId (`new`) as the new sudo
		/// key.
		#[pallet::call_index(2)]
		#[pallet::weight(T::WeightInfo::set_key())]
		pub fn set_key(
			origin: OriginFor<T>,
			new: AccountIdLookupOf<T>,
		) -> DispatchResultWithPostInfo {
			Self::ensure_sudo(origin)?;

			let new = T::Lookup::lookup(new)?;
			Self::deposit_event(Event::KeyChanged { old: Key::<T>::get(), new: new.clone() });
			Key::<T>::put(new);

			// Sudo user does not pay a fee.
			Ok(Pays::No.into())
		}

		/// Authenticates the sudo key and dispatches a function call with `Signed` origin from
		/// a given account.
		///
		/// The dispatch origin for this call must be _Signed_.
		#[pallet::call_index(3)]
		#[pallet::weight({
			let dispatch_info = call.get_dispatch_info();
			(
				T::WeightInfo::sudo_as().saturating_add(dispatch_info.weight),
				dispatch_info.class,
			)
		})]
		pub fn sudo_as(
			origin: OriginFor<T>,
			who: AccountIdLookupOf<T>,
			call: Box<<T as Config>::RuntimeCall>,
		) -> DispatchResultWithPostInfo {
			Self::ensure_sudo(origin)?;

			let who = T::Lookup::lookup(who)?;
			let res = call.dispatch_bypass_filter(RawOrigin::Signed(who).into());
			Self::deposit_event(Event::SudoAsDone {
				sudo_result: res.map(|_| ()).map_err(|e| e.error),
			});

			// Sudo user does not pay a fee.
			Ok(Pays::No.into())
		}

		/// Permanently removes the sudo key.
		///
		/// **This cannot be un-done.**
		#[pallet::call_index(4)]
		#[pallet::weight(T::WeightInfo::remove_key())]
		pub fn remove_key(origin: OriginFor<T>) -> DispatchResultWithPostInfo {
			Self::ensure_sudo(origin)?;

			Self::deposit_event(Event::KeyRemoved {});
			Key::<T>::kill();

			// Sudo user does not pay a fee.
			Ok(Pays::No.into())
		}
	}

	#[pallet::event]
	#[pallet::generate_deposit(pub(super) fn deposit_event)]
	pub enum Event<T: Config> {
		/// A sudo call just took place.
		Sudid {
			/// The result of the call made by the sudo user.
			sudo_result: DispatchResult,
		},
		/// The sudo key has been updated.
		KeyChanged {
			/// The old sudo key (if one was previously set).
			old: Option<T::AccountId>,
			/// The new sudo key (if one was set).
			new: T::AccountId,
		},
		/// The key was permanently removed.
		KeyRemoved,
		/// A [sudo_as](Pallet::sudo_as) call just took place.
		SudoAsDone {
			/// The result of the call made by the sudo user.
			sudo_result: DispatchResult,
		},
	}

	#[pallet::error]
	/// Error for the Sudo pallet.
	pub enum Error<T> {
		/// Sender must be the Sudo account.
		RequireSudo,
	}

	/// The `AccountId` of the sudo key.
	#[pallet::storage]
	pub(super) type Key<T: Config> = StorageValue<_, T::AccountId, OptionQuery>;

	#[pallet::genesis_config]
	#[derive(frame_support::DefaultNoBound)]
	pub struct GenesisConfig<T: Config> {
		/// The `AccountId` of the sudo key.
		pub key: Option<T::AccountId>,
	}

	#[pallet::genesis_build]
	impl<T: Config> BuildGenesisConfig for GenesisConfig<T> {
		fn build(&self) {
			Key::<T>::set(self.key.clone());
		}
	}

	impl<T: Config> Pallet<T> {
		/// Ensure that the caller is the sudo key.
		pub(crate) fn ensure_sudo(origin: OriginFor<T>) -> DispatchResult {
			let sender = ensure_signed_or_root(origin)?;

			if let Some(sender) = sender {
				if Key::<T>::get().map_or(false, |k| k == sender) {
					Ok(())
				} else {
					Err(Error::<T>::RequireSudo.into())
				}
			} else {
				Ok(())
			}
		}
	}
}