tendermint-lc: remove some validations

Signed-off-by: Jun Kimura <jun.kimura@datachain.jp>

Author: bluele

modules/tendermint-lc/src/client.rs

@@ -36,6 +36,7 @@ use light_client::{
     LightClientRegistry, UpdateClientResult, VerifyMembershipResult,
 };
 use light_client::{MisbehaviourData, UpdateStateData, VerifyNonMembershipResult};
+#[allow(unused_imports)]
 use log::*;
 
 #[derive(Default)]
@@ -239,37 +240,6 @@ impl TendermintLightClient {
             .into());
         }
 
-        // Read consensus state from the host chain store.
-        let latest_consensus_state: ConsensusState = ctx
-            .consensus_state(&client_id, &client_state.latest_height().into())
-            .map_err(|_| {
-                Error::ics02(ICS02Error::ConsensusStateNotFound {
-                    client_id: client_id.clone().into(),
-                    height: client_state.latest_height(),
-                })
-            })?
-            .try_into()?;
-
-        debug!("latest consensus state: {:?}", latest_consensus_state);
-
-        let now = ctx.host_timestamp();
-        let duration = now
-            .duration_since(latest_consensus_state.timestamp().into_tm_time().unwrap())
-            .map_err(|_| {
-                Error::ics02(ICS02Error::InvalidConsensusStateTimestamp {
-                    time1: latest_consensus_state.timestamp(),
-                    time2: now.into(),
-                })
-            })?;
-
-        if client_state.expired(duration) {
-            return Err(Error::ics02(ICS02Error::HeaderNotWithinTrustPeriod {
-                latest_time: latest_consensus_state.timestamp(),
-                update_time: header.timestamp(),
-            })
-            .into());
-        }
-
         let height = header.height().into();
         let header_timestamp: Time = header.timestamp().into();
 

modules/tendermint-lc/src/verifier.rs

@@ -29,25 +29,6 @@ pub(crate) fn check_header_and_update_state(
     client_id: ClientId,
     header: Any,
 ) -> Result<UpdatedState, ClientError> {
-    fn maybe_consensus_state(
-        ctx: &dyn ValidationContext,
-        client_cons_state_path: &ClientConsensusStatePath,
-    ) -> Result<Option<Box<dyn ConsensusState>>, ClientError> {
-        match ctx.consensus_state(client_cons_state_path) {
-            Ok(cs) => Ok(Some(cs)),
-            Err(e) => match e {
-                ContextError::ClientError(ClientError::ConsensusStateNotFound {
-                    client_id: _,
-                    height: _,
-                }) => Ok(None),
-                ContextError::ClientError(e) => Err(e),
-                _ => Err(ClientError::Other {
-                    description: e.to_string(),
-                }),
-            },
-        }
-    }
-
     let client_state = downcast_tm_client_state(client_state)?.clone();
     let header = TmHeader::try_from(header)?;
 
@@ -61,28 +42,6 @@ pub(crate) fn check_header_and_update_state(
         });
     }
 
-    // Check if a consensus state is already installed; if so it should
-    // match the untrusted header.
-    let header_consensus_state = TmConsensusState::from(header.clone());
-    let client_cons_state_path = ClientConsensusStatePath::new(&client_id, &header.height());
-    let existing_consensus_state = match maybe_consensus_state(ctx, &client_cons_state_path)? {
-        Some(cs) => {
-            let cs = downcast_tm_consensus_state(cs.as_ref())?;
-            // If this consensus state matches, skip verification
-            // (optimization)
-            if cs == header_consensus_state {
-                // Header is already installed and matches the incoming
-                // header (already verified)
-                return Ok(UpdatedState {
-                    client_state: client_state.into_box(),
-                    consensus_state: cs.into_box(),
-                });
-            }
-            Some(cs)
-        }
-        None => None,
-    };
-
     let trusted_client_cons_state_path =
         ClientConsensusStatePath::new(&client_id, &header.trusted_height);
     let trusted_consensus_state = downcast_tm_consensus_state(
@@ -137,77 +96,6 @@ pub(crate) fn check_header_and_update_state(
         Verdict::Invalid(detail) => Err(Error::VerificationError { detail }),
     }?;
 
-    // If the header has verified, but its corresponding consensus state
-    // differs from the existing consensus state for that height, freeze the
-    // client and return the installed consensus state.
-    if let Some(cs) = existing_consensus_state {
-        if cs != header_consensus_state {
-            return Ok(UpdatedState {
-                client_state: client_state.with_frozen_height(header.height()).into_box(),
-                consensus_state: cs.into_box(),
-            });
-        }
-    }
-
-    // Monotonicity checks for timestamps for in-the-middle updates
-    // (cs-new, cs-next, cs-latest)
-    if header.height() < client_state.latest_height() {
-        let maybe_next_cs = ctx
-            .next_consensus_state(&client_id, &header.height())
-            .map_err(|e| match e {
-                ContextError::ClientError(e) => e,
-                _ => ClientError::Other {
-                    description: e.to_string(),
-                },
-            })?
-            .as_ref()
-            .map(|cs| downcast_tm_consensus_state(cs.as_ref()))
-            .transpose()?;
-
-        if let Some(next_cs) = maybe_next_cs {
-            // New (untrusted) header timestamp cannot occur after next
-            // consensus state's height
-            if header.signed_header.header().time > next_cs.timestamp {
-                return Err(ClientError::ClientSpecific {
-                    description: Error::HeaderTimestampTooHigh {
-                        actual: header.signed_header.header().time.to_string(),
-                        max: next_cs.timestamp.to_string(),
-                    }
-                    .to_string(),
-                });
-            }
-        }
-    }
-
-    // (cs-trusted, cs-prev, cs-new)
-    if header.trusted_height < header.height() {
-        let maybe_prev_cs = ctx
-            .prev_consensus_state(&client_id, &header.height())
-            .map_err(|e| match e {
-                ContextError::ClientError(e) => e,
-                _ => ClientError::Other {
-                    description: e.to_string(),
-                },
-            })?
-            .as_ref()
-            .map(|cs| downcast_tm_consensus_state(cs.as_ref()))
-            .transpose()?;
-
-        if let Some(prev_cs) = maybe_prev_cs {
-            // New (untrusted) header timestamp cannot occur before the
-            // previous consensus state's height
-            if header.signed_header.header().time < prev_cs.timestamp {
-                return Err(ClientError::ClientSpecific {
-                    description: Error::HeaderTimestampTooLow {
-                        actual: header.signed_header.header().time.to_string(),
-                        min: prev_cs.timestamp.to_string(),
-                    }
-                    .to_string(),
-                });
-            }
-        }
-    }
-
     Ok(UpdatedState {
         client_state: client_state.with_header(header.clone())?.into_box(),
         consensus_state: TmConsensusState::from(header).into_box(),