Allow Sending XCM messages using a Signed origin on Kusama (polkadot-…

…fellows#290)

Since the introduction of this origin control, the XCMv3 release has
been integrated on Kusama, and now the `xcm-pallet` is perfectly able to
prepend a `DescendOrigin` instruction to the sent message when calling
`send`. Allowing signed origins to send messages through the network
would extend the possibilities for better integrations with parachains.

---------

Co-authored-by: fellowship-merge-bot[bot] <151052383+fellowship-merge-bot[bot]@users.noreply.github.com>

CHANGELOG.md

@@ -21,6 +21,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 - Remove one-shot migrations from Kusama Coretime ([polkadot-fellows/runtimes#300](https://github.com/polkadot-fellows/runtimes/pull/300))
 - Remove DMP queue and allow `system::authorize_upgrade` in XCM's call filter ([polkadot-fellows/runtimes#280](https://github.com/polkadot-fellows/runtimes/pull/280))
+- Allow Sending XCM messages using a Signed origin on Kusama ([polkadot-fellows/runtimes#290](https://github.com/polkadot-fellows/runtimes/pull/290))
 
 ### Fixed
 

relay/kusama/src/xcm_config.rs

@@ -248,20 +248,21 @@ pub type FellowsToPlurality = OriginToPluralityVoice<RuntimeOrigin, Fellows, Fel
 
 /// Type to convert a pallet `Origin` type value into a `Location` value which represents an
 /// interior location of this chain for a destination chain.
-pub type LocalPalletOriginToLocation = (
+pub type LocalPalletOrSignedOriginToLocation = (
 	// StakingAdmin origin to be used in XCM as a corresponding Plurality `Location` value.
 	StakingAdminToPlurality,
 	// Fellows origin to be used in XCM as a corresponding Plurality `Location` value.
 	FellowsToPlurality,
+	// And a usual Signed origin to be used in XCM as a corresponding AccountId32
+	SignedToAccountId32<RuntimeOrigin, AccountId, ThisNetwork>,
 );
 
 impl pallet_xcm::Config for Runtime {
 	type RuntimeEvent = RuntimeEvent;
-	// We only allow the root, fellows and the staking admin to send messages.
 	// This is basically safe to enable for everyone (safe the possibility of someone spamming the
-	// parachain if they're willing to pay the KSM to send from the Relay-chain), but it's useless
-	// until we bring in XCM v3 which will make `DescendOrigin` a bit more useful.
-	type SendXcmOrigin = xcm_builder::EnsureXcmOrigin<RuntimeOrigin, LocalPalletOriginToLocation>;
+	// parachain if they're willing to pay the KSM to send from the Relay-chain).
+	type SendXcmOrigin =
+		xcm_builder::EnsureXcmOrigin<RuntimeOrigin, LocalPalletOrSignedOriginToLocation>;
 	type XcmRouter = XcmRouter;
 	// Anyone can execute XCM messages locally.
 	type ExecuteXcmOrigin = xcm_builder::EnsureXcmOrigin<RuntimeOrigin, LocalOriginToLocation>;