feat: align derivation accross ecosystem

parachain/runtime/interlay/src/xcm_config.rs

@@ -39,6 +39,8 @@ type LocationToAccountId = (
     SiblingParachainConvertsVia<Sibling, AccountId>,
     // Straight up local `AccountId32` origins just alias directly to `AccountId`.
     AccountId32Aliases<ParentNetwork, AccountId>,
+    // Generate remote accounts according to polkadot standards
+    primitives::xcm::HashedDescriptionDescribeFamilyAllTerminal<AccountId>,
 );
 
 /// This is the type we use to convert an (incoming) XCM origin into a local `Origin` instance,

parachain/runtime/kintsugi/src/xcm_config.rs

@@ -37,6 +37,8 @@ type LocationToAccountId = (
     SiblingParachainConvertsVia<Sibling, AccountId>,
     // Straight up local `AccountId32` origins just alias directly to `AccountId`.
     AccountId32Aliases<ParentNetwork, AccountId>,
+    // Generate remote accounts according to polkadot standards
+    primitives::xcm::HashedDescriptionDescribeFamilyAllTerminal<AccountId>,
 );
 
 /// This is the type we use to convert an (incoming) XCM origin into a local `Origin` instance,

primitives/src/lib.rs

@@ -639,3 +639,161 @@ impl From<u32> for CurrencyId {
         }
     }
 }
+
+pub mod xcm {
+    use codec::{Compact, Encode};
+    use sp_io::hashing::blake2_256;
+    use sp_std::{borrow::Borrow, marker::PhantomData, vec::Vec};
+    use xcm::prelude::{
+        AccountId32, AccountKey20, Here, MultiLocation, PalletInstance, Parachain, X1,
+    };
+    use xcm_executor::traits::Convert;
+
+    /// NOTE: Copied from <https://github.com/moonbeam-foundation/polkadot/blob/d83bb6cc7d7c93ead2fd3cafce0e268fd3f6b9bc/xcm/xcm-builder/src/location_conversion.rs#L25C1-L68C2>
+    ///
+    /// temporary struct that mimics the behavior of the upstream type that we
+    /// will move to once we update this repository to Polkadot 0.9.43+.
+    pub struct HashedDescriptionDescribeFamilyAllTerminal<AccountId>(PhantomData<AccountId>);
+    impl<AccountId: From<[u8; 32]> + Clone> HashedDescriptionDescribeFamilyAllTerminal<AccountId> {
+        fn describe_location_suffix(l: &MultiLocation) -> Result<Vec<u8>, ()> {
+            match (l.parents, &l.interior) {
+                (0, Here) => Ok(Vec::new()),
+                (0, X1(PalletInstance(i))) => {
+                    Ok((b"Pallet", Compact::<u32>::from(*i as u32)).encode())
+                }
+                (0, X1(AccountId32 { id, .. })) => Ok((b"AccountId32", id).encode()),
+                (0, X1(AccountKey20 { key, .. })) => Ok((b"AccountKey20", key).encode()),
+                _ => Err(()),
+            }
+        }
+    }
+
+    impl<AccountId: From<[u8; 32]> + Clone> Convert<MultiLocation, AccountId>
+    for HashedDescriptionDescribeFamilyAllTerminal<AccountId>
+    {
+        fn convert_ref(location: impl Borrow<MultiLocation>) -> Result<AccountId, ()> {
+            let l = location.borrow();
+            let to_hash = match (l.parents, l.interior.first()) {
+                (0, Some(Parachain(index))) => {
+                    let tail = l.interior.split_first().0;
+                    let interior = Self::describe_location_suffix(&tail.into())?;
+                    (b"ChildChain", Compact::<u32>::from(*index), interior).encode()
+                }
+                (1, Some(Parachain(index))) => {
+                    let tail = l.interior.split_first().0;
+                    let interior = Self::describe_location_suffix(&tail.into())?;
+                    (b"SiblingChain", Compact::<u32>::from(*index), interior).encode()
+                }
+                (1, _) => {
+                    let tail = l.interior.into();
+                    let interior = Self::describe_location_suffix(&tail)?;
+                    (b"ParentChain", interior).encode()
+                }
+                _ => return Err(()),
+            };
+            Ok(blake2_256(&to_hash).into())
+        }
+
+        fn reverse_ref(_: impl Borrow<AccountId>) -> Result<MultiLocation, ()> {
+            Err(())
+        }
+    }
+
+    #[test]
+    fn test_hashed_family_all_terminal_converter() {
+        use xcm::prelude::X2;
+
+        type Converter<AccountId> = HashedDescriptionDescribeFamilyAllTerminal<AccountId>;
+
+        assert_eq!(
+            [
+                129, 211, 14, 6, 146, 54, 225, 200, 135, 103, 248, 244, 125, 112, 53, 133, 91, 42,
+                215, 236, 154, 199, 191, 208, 110, 148, 223, 55, 92, 216, 250, 34
+            ],
+            Converter::<[u8; 32]>::convert(MultiLocation {
+                parents: 0,
+                interior: X2(
+                    Parachain(1),
+                    AccountId32 {
+                        network: None,
+                        id: [0u8; 32]
+                    }
+                ),
+            })
+                .unwrap()
+        );
+        assert_eq!(
+            [
+                17, 142, 105, 253, 199, 34, 43, 136, 155, 48, 12, 137, 155, 219, 155, 110, 93, 181,
+                93, 252, 124, 60, 250, 195, 229, 86, 31, 220, 121, 111, 254, 252
+            ],
+            Converter::<[u8; 32]>::convert(MultiLocation {
+                parents: 1,
+                interior: X2(
+                    Parachain(1),
+                    AccountId32 {
+                        network: None,
+                        id: [0u8; 32]
+                    }
+                ),
+            })
+                .unwrap()
+        );
+        assert_eq!(
+            [
+                237, 65, 190, 49, 53, 182, 196, 183, 151, 24, 214, 23, 72, 244, 235, 87, 187, 67,
+                52, 122, 195, 192, 10, 58, 253, 49, 0, 112, 175, 224, 125, 66
+            ],
+            Converter::<[u8; 32]>::convert(MultiLocation {
+                parents: 0,
+                interior: X2(
+                    Parachain(1),
+                    AccountKey20 {
+                        network: None,
+                        key: [0u8; 20]
+                    }
+                ),
+            })
+                .unwrap()
+        );
+        assert_eq!(
+            [
+                226, 225, 225, 162, 254, 156, 113, 95, 68, 155, 160, 118, 126, 18, 166, 132, 144,
+                19, 8, 204, 228, 112, 164, 189, 179, 124, 249, 1, 168, 110, 151, 50
+            ],
+            Converter::<[u8; 32]>::convert(MultiLocation {
+                parents: 1,
+                interior: X2(
+                    Parachain(1),
+                    AccountKey20 {
+                        network: None,
+                        key: [0u8; 20]
+                    }
+                ),
+            })
+                .unwrap()
+        );
+        assert_eq!(
+            [
+                254, 186, 179, 229, 13, 24, 84, 36, 84, 35, 64, 95, 114, 136, 62, 69, 247, 74, 215,
+                104, 121, 114, 53, 6, 124, 46, 42, 245, 121, 197, 12, 208
+            ],
+            Converter::<[u8; 32]>::convert(MultiLocation {
+                parents: 1,
+                interior: X2(Parachain(2), PalletInstance(3)),
+            })
+                .unwrap()
+        );
+        assert_eq!(
+            [
+                217, 56, 0, 36, 228, 154, 250, 26, 200, 156, 1, 39, 254, 162, 16, 187, 107, 67, 27,
+                16, 218, 254, 250, 184, 6, 27, 216, 138, 194, 93, 23, 165
+            ],
+            Converter::<[u8; 32]>::convert(MultiLocation {
+                parents: 1,
+                interior: Here,
+            })
+                .unwrap()
+        );
+    }
+}