Check if ClientStatePath is empty during client creation (#605)

* Check if ClientStatePath is empty during client creation

* Rewrite ClientState present check with is_ok

.changelog/unreleased/breaking-changes/604-fix-unchecked-clientstatepath.md

@@ -0,0 +1,2 @@
+- Check if `ClientStatePath` is empty during client creation process
+ ([#604](https://github.com/cosmos/ibc-rs/issues/604))

crates/ibc/src/core/ics02_client/error.rs

@@ -19,10 +19,12 @@ pub enum ClientError {
  counter: u64,
  validation_error: ValidationError,
  },
- /// client not found: `{client_id}`
- ClientNotFound { client_id: ClientId },
  /// client is frozen with description: `{description}`
  ClientFrozen { description: String },
+ /// client state not found: `{client_id}`
+ ClientStateNotFound { client_id: ClientId },
+ /// client state already exists: `{client_id}`
+ ClientStateAlreadyExists { client_id: ClientId },
  /// consensus state not found at: `{client_id}` at height `{height}`
  ConsensusStateNotFound { client_id: ClientId, height: Height },
  /// implementation specific error

crates/ibc/src/core/ics02_client/handler/create_client.rs

@@ -37,14 +37,18 @@ where
 
  let client_type = client_state.client_type();
 
- let _client_id = ClientId::new(client_type, id_counter).map_err(|e| {
+ let client_id = ClientId::new(client_type, id_counter).map_err(|e| {
  ClientError::ClientIdentifierConstructor {
  client_type: client_state.client_type(),
  counter: id_counter,
  validation_error: e,
  }
  })?;
 
+ if ctx.client_state(&client_id).is_ok() {
+ return Err(ClientError::ClientStateAlreadyExists { client_id }.into());
+ };
+
  Ok(())
 }
 

crates/ibc/src/mock/context.rs

@@ -715,11 +715,11 @@ impl ValidationContext for MockContext {
  client_record
  .client_state
  .clone()
- .ok_or_else(|| ClientError::ClientNotFound {
+ .ok_or_else(|| ClientError::ClientStateNotFound {
  client_id: client_id.clone(),
  })
  }
- None => Err(ClientError::ClientNotFound {
+ None => Err(ClientError::ClientStateNotFound {
  client_id: client_id.clone(),
  }),
  }
@@ -771,7 +771,7 @@ impl ValidationContext for MockContext {
  ibc_store
  .clients
  .get(client_id)
- .ok_or_else(|| ClientError::ClientNotFound {
+ .ok_or_else(|| ClientError::ClientStateNotFound {
  client_id: client_id.clone(),
  })?;
 
@@ -801,7 +801,7 @@ impl ValidationContext for MockContext {
  ibc_store
  .clients
  .get(client_id)
- .ok_or_else(|| ClientError::ClientNotFound {
+ .ok_or_else(|| ClientError::ClientStateNotFound {
  client_id: client_id.clone(),
  })?;