Allow ChainEndpoint implementations to fetch any types of clients a…

…nd consensus states (#1625)

.changelog/unreleased/improvements/ibc-relayer/1481-chainendpoint-any-consensus-state.md

@@ -0,0 +1,3 @@
+- Allow `ChainEndpoint` implementations to fetch any types of clients
+  and consensus states ([#1481](https://github.com/informalsystems/ibc-
+  rs/issues/1481))

modules/src/clients/ics07_tendermint/client_state.rs

@@ -139,18 +139,6 @@ impl ClientState {
         })
     }
 
-    /// Helper function to verify the upgrade client procedure.
-    /// Resets all fields except the blockchain-specific ones.
-    pub fn zero_custom_fields(mut client_state: Self) -> Self {
-        client_state.trusting_period = ZERO_DURATION;
-        client_state.trust_level = TrustThreshold::ZERO;
-        client_state.allow_update.after_expiry = false;
-        client_state.allow_update.after_misbehaviour = false;
-        client_state.frozen_height = None;
-        client_state.max_clock_drift = ZERO_DURATION;
-        client_state
-    }
-
     /// Get the refresh time to ensure the state does not expire
     pub fn refresh_time(&self) -> Option<Duration> {
         Some(2 * self.trusting_period / 3)
@@ -217,7 +205,14 @@ impl ClientState {
     }
 }
 
+#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize)]
+pub struct UpgradeOptions {
+    pub unbonding_period: Duration,
+}
+
 impl crate::core::ics02_client::client_state::ClientState for ClientState {
+    type UpgradeOptions = UpgradeOptions;
+
     fn chain_id(&self) -> ChainId {
         self.chain_id.clone()
     }
@@ -234,6 +229,28 @@ impl crate::core::ics02_client::client_state::ClientState for ClientState {
         self.frozen_height
     }
 
+    fn upgrade(
+        mut self,
+        upgrade_height: Height,
+        upgrade_options: UpgradeOptions,
+        chain_id: ChainId,
+    ) -> Self {
+        // Reset custom fields to zero values
+        self.trusting_period = ZERO_DURATION;
+        self.trust_level = TrustThreshold::ZERO;
+        self.allow_update.after_expiry = false;
+        self.allow_update.after_misbehaviour = false;
+        self.frozen_height = None;
+        self.max_clock_drift = ZERO_DURATION;
+
+        // Upgrade the client state
+        self.latest_height = upgrade_height;
+        self.unbonding_period = upgrade_options.unbonding_period;
+        self.chain_id = chain_id;
+
+        self
+    }
+
     fn wrap_any(self) -> AnyClientState {
         AnyClientState::Tendermint(self)
     }

modules/src/clients/ics07_tendermint/consensus_state.rs

@@ -43,10 +43,6 @@ impl crate::core::ics02_client::client_consensus::ConsensusState for ConsensusSt
         &self.root
     }
 
-    fn validate_basic(&self) -> Result<(), Infallible> {
-        unimplemented!()
-    }
-
     fn wrap_any(self) -> AnyConsensusState {
         AnyConsensusState::Tendermint(self)
     }

modules/src/core/ics02_client/client_consensus.rs

@@ -34,9 +34,6 @@ pub trait ConsensusState: Clone + core::fmt::Debug + Send + Sync {
     /// Commitment root of the consensus state, which is used for key-value pair verification.
     fn root(&self) -> &CommitmentRoot;
 
-    /// Performs basic validation of the consensus state
-    fn validate_basic(&self) -> Result<(), Self::Error>;
-
     /// Wrap into an `AnyConsensusState`
     fn wrap_any(self) -> AnyConsensusState;
 }
@@ -165,15 +162,6 @@ impl ConsensusState for AnyConsensusState {
         }
     }
 
-    fn validate_basic(&self) -> Result<(), Infallible> {
-        match self {
-            Self::Tendermint(cs_state) => cs_state.validate_basic(),
-
-            #[cfg(any(test, feature = "mocks"))]
-            Self::Mock(mock_state) => mock_state.validate_basic(),
-        }
-    }
-
     fn wrap_any(self) -> AnyConsensusState {
         self
     }

modules/src/core/ics02_client/client_state.rs

@@ -22,6 +22,9 @@ pub const TENDERMINT_CLIENT_STATE_TYPE_URL: &str = "/ibc.lightclients.tendermint
 pub const MOCK_CLIENT_STATE_TYPE_URL: &str = "/ibc.mock.ClientState";
 
 pub trait ClientState: Clone + core::fmt::Debug + Send + Sync {
+    /// Client-specific options for upgrading the client
+    type UpgradeOptions;
+
     /// Return the chain identifier which this client is serving (i.e., the client is verifying
     /// consensus states from this chain).
     fn chain_id(&self) -> ChainId;
@@ -40,10 +43,42 @@ pub trait ClientState: Clone + core::fmt::Debug + Send + Sync {
     /// Frozen height of the client
     fn frozen_height(&self) -> Option<Height>;
 
+    /// Helper function to verify the upgrade client procedure.
+    /// Resets all fields except the blockchain-specific ones,
+    /// and updates the given fields.
+    fn upgrade(
+        self,
+        upgrade_height: Height,
+        upgrade_options: Self::UpgradeOptions,
+        chain_id: ChainId,
+    ) -> Self;
+
     /// Wrap into an `AnyClientState`
     fn wrap_any(self) -> AnyClientState;
 }
 
+#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize)]
+#[serde(tag = "type")]
+pub enum AnyUpgradeOptions {
+    Tendermint(client_state::UpgradeOptions),
+
+    #[cfg(any(test, feature = "mocks"))]
+    Mock(()),
+}
+
+impl AnyUpgradeOptions {
+    fn into_tendermint(self) -> client_state::UpgradeOptions {
+        match self {
+            Self::Tendermint(options) => options,
+
+            #[cfg(any(test, feature = "mocks"))]
+            Self::Mock(_) => {
+                panic!("cannot downcast AnyUpgradeOptions::Mock to Tendermint::UpgradeOptions")
+            }
+        }
+    }
+}
+
 #[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize)]
 #[serde(tag = "type")]
 pub enum AnyClientState {
@@ -163,6 +198,8 @@ impl From<AnyClientState> for Any {
 }
 
 impl ClientState for AnyClientState {
+    type UpgradeOptions = AnyUpgradeOptions;
+
     fn chain_id(&self) -> ChainId {
         match self {
             AnyClientState::Tendermint(tm_state) => tm_state.chain_id(),
@@ -184,6 +221,24 @@ impl ClientState for AnyClientState {
         self.frozen_height()
     }
 
+    fn upgrade(
+        self,
+        upgrade_height: Height,
+        upgrade_options: Self::UpgradeOptions,
+        chain_id: ChainId,
+    ) -> Self {
+        match self {
+            AnyClientState::Tendermint(tm_state) => tm_state
+                .upgrade(upgrade_height, upgrade_options.into_tendermint(), chain_id)
+                .wrap_any(),
+
+            #[cfg(any(test, feature = "mocks"))]
+            AnyClientState::Mock(mock_state) => {
+                mock_state.upgrade(upgrade_height, (), chain_id).wrap_any()
+            }
+        }
+    }
+
     fn wrap_any(self) -> AnyClientState {
         self
     }

modules/src/mock/client_state.rs

@@ -92,6 +92,8 @@ impl From<MockClientState> for RawMockClientState {
 }
 
 impl ClientState for MockClientState {
+    type UpgradeOptions = ();
+
     fn chain_id(&self) -> ChainId {
         todo!()
     }
@@ -108,6 +110,10 @@ impl ClientState for MockClientState {
         self.frozen_height
     }
 
+    fn upgrade(self, _upgrade_height: Height, _upgrade_options: (), _chain_id: ChainId) -> Self {
+        todo!()
+    }
+
     fn wrap_any(self) -> AnyClientState {
         AnyClientState::Mock(self)
     }
@@ -181,10 +187,6 @@ impl ConsensusState for MockConsensusState {
         &self.root
     }
 
-    fn validate_basic(&self) -> Result<(), Infallible> {
-        Ok(())
-    }
-
     fn wrap_any(self) -> AnyConsensusState {
         AnyConsensusState::Mock(self)
     }

relayer/src/chain.rs

@@ -169,7 +169,7 @@ pub trait ChainEndpoint: Sized {
         &self,
         client_id: &ClientId,
         height: ICSHeight,
-    ) -> Result<Self::ClientState, Error>;
+    ) -> Result<AnyClientState, Error>;
 
     fn query_consensus_states(
         &self,
@@ -188,12 +188,12 @@ pub trait ChainEndpoint: Sized {
     fn query_upgraded_client_state(
         &self,
         height: ICSHeight,
-    ) -> Result<(Self::ClientState, MerkleProof), Error>;
+    ) -> Result<(AnyClientState, MerkleProof), Error>;
 
     fn query_upgraded_consensus_state(
         &self,
         height: ICSHeight,
-    ) -> Result<(Self::ConsensusState, MerkleProof), Error>;
+    ) -> Result<(AnyConsensusState, MerkleProof), Error>;
 
     /// Performs a query to retrieve the identifiers of all connections.
     fn query_connections(
@@ -276,7 +276,7 @@ pub trait ChainEndpoint: Sized {
         &self,
         client_id: &ClientId,
         height: ICSHeight,
-    ) -> Result<(Self::ClientState, MerkleProof), Error>;
+    ) -> Result<(AnyClientState, MerkleProof), Error>;
 
     fn proven_connection(
         &self,
@@ -289,7 +289,7 @@ pub trait ChainEndpoint: Sized {
         client_id: &ClientId,
         consensus_height: ICSHeight,
         height: ICSHeight,
-    ) -> Result<(Self::ConsensusState, MerkleProof), Error>;
+    ) -> Result<(AnyConsensusState, MerkleProof), Error>;
 
     fn proven_channel(
         &self,
@@ -339,7 +339,7 @@ pub trait ChainEndpoint: Sized {
         connection_id: &ConnectionId,
         client_id: &ClientId,
         height: ICSHeight,
-    ) -> Result<(Option<Self::ClientState>, Proofs), Error> {
+    ) -> Result<(Option<AnyClientState>, Proofs), Error> {
         let (connection_end, connection_proof) = self.proven_connection(connection_id, height)?;
 
         // Check that the connection state is compatible with the message