From d569e728ca710c64392e524c9ccd4ec10c370269 Mon Sep 17 00:00:00 2001
From: Branislav Kontur <bkontur@gmail.com>
Date: Mon, 18 Sep 2023 11:11:08 +0200
Subject: [PATCH] "Common good" vs "System" parachain clean up (#1406)
## Summary
The term "common good parachain" has been abandoned in favor of "system
parachain" - e.g. [Joe's speech at
Decoded2023](https://youtu.be/CSO-ERHK2gY?t=456). This pull request
tries to fix and align code with this vision.
## Impact
The important change is implementation of `trait IsSystem` for `Id`
[here](https://github.com/paritytech/polkadot-sdk/pull/1406/files#diff-0b7b4f5b962a18ce980354592b55ab2a27b5a2e9f6f8089ec803ca73853e8583R225-R229)
where we changed condition from `< 1000` to `<= 1999`, which means that
all parachain IDs bellow 1999 (included) are considered as "system
parachain" IDs. This change has a direct impact on the following
components:
####
[ChildSystemParachainAsSuperuser](https://github.com/paritytech/polkadot-sdk/blob/master/polkadot/xcm/xcm-builder/src/origin_conversion.rs#L72-L88)
This origin converter is used for allowing to process XCM `Transact`
from "system parachain" on the relay chain - e.g. see [configuration for
Kusama](https://github.com/paritytech/polkadot-sdk/blob/master/polkadot/runtime/kusama/src/xcm_config.rs#L92-L101).
Only configured for Kusama, Westend, Rococo runtimes.
**No need for this feature anymore.** See
[comment](https://github.com/paritytech/polkadot-sdk/pull/1406#issuecomment-1708218715).
####
[IsChildSystemParachain](https://github.com/paritytech/polkadot-sdk/blob/master/polkadot/xcm/xcm-builder/src/barriers.rs#L310-L317)
`IsChildSystemParachain` is used with `AllowExplicitUnpaidExecutionFrom`
barrier for checking XCM programs (they have to start with
`UnpaidExecution` instruction).
Only configured for Kusama, Westend, Rococo runtimes.
**Overall the impact is low or mostly ok because it only allows unpaid
execution for "system parachains" (e.g. AssetHub, BridgeHub...) on the
relay chain.**
####
[SiblingSystemParachainAsSuperuser](https://github.com/paritytech/polkadot-sdk/blob/master/polkadot/xcm/xcm-builder/src/origin_conversion.rs#L94-L114)
Not used anywhere in `polkadot-sdk` repo.
## Unresolved Questions
- [ ] constants `LOWEST_USER_ID` and `LOWEST_PUBLIC_ID` seem to express
the same thing now, do we want to keep them both or deprecated one of
them? If so, which one?
- [x] determine impact for `ChildSystemParachainAsSuperuser`
## TODO
- [ ] when merged here, open PR to the `polkadot-fellows`
## Related Material
https://youtu.be/CSO-ERHK2gY?t=456
https://forum.polkadot.network/t/polkadot-protocol-and-common-good-parachains/866
https://wiki.polkadot.network/docs/learn-system-chains
---
.../collectives/collectives-polkadot/src/lib.rs | 2 +-
.../runtimes/testing/penpal/src/xcm_config.rs | 2 +-
polkadot/parachain/src/primitives.rs | 10 ++++------
polkadot/primitives/src/v5/mod.rs | 2 +-
polkadot/runtime/kusama/src/lib.rs | 2 +-
polkadot/runtime/kusama/src/xcm_config.rs | 11 ++++-------
polkadot/runtime/polkadot/src/lib.rs | 2 +-
polkadot/runtime/rococo/src/xcm_config.rs | 11 ++++-------
polkadot/runtime/westend/src/xcm_config.rs | 9 ++++-----
9 files changed, 21 insertions(+), 30 deletions(-)
diff --git a/cumulus/parachains/runtimes/collectives/collectives-polkadot/src/lib.rs b/cumulus/parachains/runtimes/collectives/collectives-polkadot/src/lib.rs
index d9125c2645e..70e62a4dcdf 100644
--- a/cumulus/parachains/runtimes/collectives/collectives-polkadot/src/lib.rs
+++ b/cumulus/parachains/runtimes/collectives/collectives-polkadot/src/lib.rs
@@ -20,7 +20,7 @@
//!
//! ### Governance
//!
-//! As a common good parachain, Collectives defers its governance (namely, its `Root` origin), to
+//! As a system parachain, Collectives defers its governance (namely, its `Root` origin), to
//! its Relay Chain parent, Polkadot.
//!
//! ### Collator Selection
diff --git a/cumulus/parachains/runtimes/testing/penpal/src/xcm_config.rs b/cumulus/parachains/runtimes/testing/penpal/src/xcm_config.rs
index 97d2e63370e..f2ffc451b10 100644
--- a/cumulus/parachains/runtimes/testing/penpal/src/xcm_config.rs
+++ b/cumulus/parachains/runtimes/testing/penpal/src/xcm_config.rs
@@ -163,7 +163,7 @@ pub type Barrier = TrailingSetTopicAsId<
// If the message is one that immediately attemps to pay for execution, then
// allow it.
AllowTopLevelPaidExecutionFrom<Everything>,
- // Common Good Assets parachain, parent and its exec plurality get free
+ // System Assets parachain, parent and its exec plurality get free
// execution
AllowExplicitUnpaidExecutionFrom<(
CommonGoodAssetsParachain,
diff --git a/polkadot/parachain/src/primitives.rs b/polkadot/parachain/src/primitives.rs
index 5cea9d3bbf4..5f77810f5c2 100644
--- a/polkadot/parachain/src/primitives.rs
+++ b/polkadot/parachain/src/primitives.rs
@@ -199,13 +199,11 @@ impl From<i32> for Id {
}
}
-const USER_INDEX_START: u32 = 1000;
+// System parachain ID is considered `< 2000`.
+const SYSTEM_INDEX_END: u32 = 1999;
const PUBLIC_INDEX_START: u32 = 2000;
-/// The ID of the first user (non-system) parachain.
-pub const LOWEST_USER_ID: Id = Id(USER_INDEX_START);
-
-/// The ID of the first publicly registerable parachain.
+/// The ID of the first publicly registrable parachain.
pub const LOWEST_PUBLIC_ID: Id = Id(PUBLIC_INDEX_START);
impl Id {
@@ -223,7 +221,7 @@ pub trait IsSystem {
impl IsSystem for Id {
fn is_system(&self) -> bool {
- self.0 < USER_INDEX_START
+ self.0 <= SYSTEM_INDEX_END
}
}
diff --git a/polkadot/primitives/src/v5/mod.rs b/polkadot/primitives/src/v5/mod.rs
index 30782f95611..81743225403 100644
--- a/polkadot/primitives/src/v5/mod.rs
+++ b/polkadot/primitives/src/v5/mod.rs
@@ -44,7 +44,7 @@ pub use polkadot_core_primitives::v2::{
// Export some polkadot-parachain primitives
pub use polkadot_parachain_primitives::primitives::{
HeadData, HorizontalMessages, HrmpChannelId, Id, UpwardMessage, UpwardMessages, ValidationCode,
- ValidationCodeHash, LOWEST_PUBLIC_ID, LOWEST_USER_ID,
+ ValidationCodeHash, LOWEST_PUBLIC_ID,
};
use serde::{Deserialize, Serialize};
diff --git a/polkadot/runtime/kusama/src/lib.rs b/polkadot/runtime/kusama/src/lib.rs
index fc9fd61790e..0681db23bc2 100644
--- a/polkadot/runtime/kusama/src/lib.rs
+++ b/polkadot/runtime/kusama/src/lib.rs
@@ -643,7 +643,7 @@ impl pallet_staking::EraPayout<Balance> for EraPayout {
// all para-ids that are currently active.
let auctioned_slots = Paras::parachains()
.into_iter()
- // all active para-ids that do not belong to a system or common good chain is the number
+ // all active para-ids that do not belong to a system chain is the number
// of parachains that we should take into account for inflation.
.filter(|i| *i >= LOWEST_PUBLIC_ID)
.count() as u64;
diff --git a/polkadot/runtime/kusama/src/xcm_config.rs b/polkadot/runtime/kusama/src/xcm_config.rs
index 6a9cea22bbc..59ea937e11c 100644
--- a/polkadot/runtime/kusama/src/xcm_config.rs
+++ b/polkadot/runtime/kusama/src/xcm_config.rs
@@ -37,11 +37,10 @@ use xcm::latest::prelude::*;
use xcm_builder::{
AccountId32Aliases, AllowExplicitUnpaidExecutionFrom, AllowKnownQueryResponses,
AllowSubscriptionsFrom, AllowTopLevelPaidExecutionFrom, ChildParachainAsNative,
- ChildParachainConvertsVia, ChildSystemParachainAsSuperuser,
- CurrencyAdapter as XcmCurrencyAdapter, IsChildSystemParachain, IsConcrete, MintLocation,
- OriginToPluralityVoice, SignedAccountId32AsNative, SignedToAccountId32,
- SovereignSignedViaLocation, TakeWeightCredit, TrailingSetTopicAsId, UsingComponents,
- WeightInfoBounds, WithComputedOrigin, WithUniqueTopic,
+ ChildParachainConvertsVia, CurrencyAdapter as XcmCurrencyAdapter, IsChildSystemParachain,
+ IsConcrete, MintLocation, OriginToPluralityVoice, SignedAccountId32AsNative,
+ SignedToAccountId32, SovereignSignedViaLocation, TakeWeightCredit, TrailingSetTopicAsId,
+ UsingComponents, WeightInfoBounds, WithComputedOrigin, WithUniqueTopic,
};
parameter_types! {
@@ -95,8 +94,6 @@ type LocalOriginConverter = (
ChildParachainAsNative<parachains_origin::Origin, RuntimeOrigin>,
// The AccountId32 location type can be expressed natively as a `Signed` origin.
SignedAccountId32AsNative<ThisNetwork, RuntimeOrigin>,
- // A system child parachain, expressed as a Superuser, converts to the `Root` origin.
- ChildSystemParachainAsSuperuser<ParaId, RuntimeOrigin>,
);
parameter_types! {
diff --git a/polkadot/runtime/polkadot/src/lib.rs b/polkadot/runtime/polkadot/src/lib.rs
index 6d06ee46933..441a5132eda 100644
--- a/polkadot/runtime/polkadot/src/lib.rs
+++ b/polkadot/runtime/polkadot/src/lib.rs
@@ -552,7 +552,7 @@ impl pallet_staking::EraPayout<Balance> for EraPayout {
// all para-ids that are not active.
let auctioned_slots = Paras::parachains()
.into_iter()
- // all active para-ids that do not belong to a system or common good chain is the number
+ // all active para-ids that do not belong to a system chain is the number
// of parachains that we should take into account for inflation.
.filter(|i| *i >= LOWEST_PUBLIC_ID)
.count() as u64;
diff --git a/polkadot/runtime/rococo/src/xcm_config.rs b/polkadot/runtime/rococo/src/xcm_config.rs
index d561df14a02..288ee8400dc 100644
--- a/polkadot/runtime/rococo/src/xcm_config.rs
+++ b/polkadot/runtime/rococo/src/xcm_config.rs
@@ -36,11 +36,10 @@ use xcm::latest::prelude::*;
use xcm_builder::{
AccountId32Aliases, AllowExplicitUnpaidExecutionFrom, AllowKnownQueryResponses,
AllowSubscriptionsFrom, AllowTopLevelPaidExecutionFrom, ChildParachainAsNative,
- ChildParachainConvertsVia, ChildSystemParachainAsSuperuser,
- CurrencyAdapter as XcmCurrencyAdapter, FixedWeightBounds, IsChildSystemParachain, IsConcrete,
- MintLocation, SignedAccountId32AsNative, SignedToAccountId32, SovereignSignedViaLocation,
- TakeWeightCredit, TrailingSetTopicAsId, UsingComponents, WeightInfoBounds, WithComputedOrigin,
- WithUniqueTopic,
+ ChildParachainConvertsVia, CurrencyAdapter as XcmCurrencyAdapter, FixedWeightBounds,
+ IsChildSystemParachain, IsConcrete, MintLocation, SignedAccountId32AsNative,
+ SignedToAccountId32, SovereignSignedViaLocation, TakeWeightCredit, TrailingSetTopicAsId,
+ UsingComponents, WeightInfoBounds, WithComputedOrigin, WithUniqueTopic,
};
use xcm_executor::XcmExecutor;
@@ -80,8 +79,6 @@ type LocalOriginConverter = (
ChildParachainAsNative<parachains_origin::Origin, RuntimeOrigin>,
// The AccountId32 location type can be expressed natively as a `Signed` origin.
SignedAccountId32AsNative<ThisNetwork, RuntimeOrigin>,
- // A system child parachain, expressed as a Superuser, converts to the `Root` origin.
- ChildSystemParachainAsSuperuser<ParaId, RuntimeOrigin>,
);
parameter_types! {
diff --git a/polkadot/runtime/westend/src/xcm_config.rs b/polkadot/runtime/westend/src/xcm_config.rs
index 264830c693e..afa0733b4c9 100644
--- a/polkadot/runtime/westend/src/xcm_config.rs
+++ b/polkadot/runtime/westend/src/xcm_config.rs
@@ -35,10 +35,10 @@ use xcm::latest::prelude::*;
use xcm_builder::{
AccountId32Aliases, AllowExplicitUnpaidExecutionFrom, AllowKnownQueryResponses,
AllowSubscriptionsFrom, AllowTopLevelPaidExecutionFrom, ChildParachainAsNative,
- ChildParachainConvertsVia, ChildSystemParachainAsSuperuser,
- CurrencyAdapter as XcmCurrencyAdapter, IsChildSystemParachain, IsConcrete, MintLocation,
- SignedAccountId32AsNative, SignedToAccountId32, SovereignSignedViaLocation, TakeWeightCredit,
- TrailingSetTopicAsId, UsingComponents, WeightInfoBounds, WithComputedOrigin, WithUniqueTopic,
+ ChildParachainConvertsVia, CurrencyAdapter as XcmCurrencyAdapter, IsChildSystemParachain,
+ IsConcrete, MintLocation, SignedAccountId32AsNative, SignedToAccountId32,
+ SovereignSignedViaLocation, TakeWeightCredit, TrailingSetTopicAsId, UsingComponents,
+ WeightInfoBounds, WithComputedOrigin, WithUniqueTopic,
};
use xcm_executor::XcmExecutor;
@@ -74,7 +74,6 @@ type LocalOriginConverter = (
SovereignSignedViaLocation<LocationConverter, RuntimeOrigin>,
ChildParachainAsNative<parachains_origin::Origin, RuntimeOrigin>,
SignedAccountId32AsNative<ThisNetwork, RuntimeOrigin>,
- ChildSystemParachainAsSuperuser<ParaId, RuntimeOrigin>,
);
/// The XCM router. When we want to send an XCM message, we use this type. It amalgamates all of our
--
GitLab