chore: update exposed db object Evidence in x/finality module (#208)

Part closes: babylonlabs-io/pm#72

Currently some of the objects in the babylon apis are exposed and need
to be handled correctly seen in
babylonlabs-io/pm#72

This PR handles the exposed objects in `x/finality`

Specifically the `Evidence` object.

CHANGELOG.md

@@ -53,6 +53,7 @@ to total bonded sat
 * [#201](https://github.com/babylonlabs-io/babylon/pull/201) Adjusted handling of `ValidatorWithBlsKey` in checkpoint keeper queries to improve API security.
 * [#202](https://github.com/babylonlabs-io/babylon/pull/202) Adjusted handling of `FinalityProviderWithMeta` in btcstaking keeper queries to improve API security.
 * [#203](https://github.com/babylonlabs-io/babylon/pull/203) Adjusted handling of `RewardGauge` in incentive keeper queries to improve API security.
+* [#208](https://github.com/babylonlabs-io/babylon/pull/208) Adjusted handling of `Evidence` in finality keeper queries to improve API security.
 
 ### State Machine Breaking
 

proto/babylon/finality/v1/query.proto

@@ -196,10 +196,33 @@ message QueryEvidenceRequest {
   string fp_btc_pk_hex = 1;
 }
 
+// Evidence is the evidence that a finality provider has signed finality
+// signatures with correct public randomness on two conflicting Babylon headers
+message EvidenceResponse {
+    // fp_btc_pk_hex is the BTC PK of the finality provider that casts this vote
+    string fp_btc_pk_hex = 1;
+    // block_height is the height of the conflicting blocks
+    uint64 block_height = 2;
+    // pub_rand is the public randomness the finality provider has committed to
+    bytes pub_rand = 3 [ (gogoproto.customtype) = "github.com/babylonlabs-io/babylon/types.SchnorrPubRand" ];
+    // canonical_app_hash is the AppHash of the canonical block
+    bytes canonical_app_hash = 4;
+    // fork_app_hash is the AppHash of the fork block
+    bytes fork_app_hash = 5;
+    // canonical_finality_sig is the finality signature to the canonical block
+    // where finality signature is an EOTS signature, i.e.,
+    // the `s` in a Schnorr signature `(r, s)`
+    // `r` is the public randomness that is already committed by the finality provider
+    bytes canonical_finality_sig = 6 [ (gogoproto.customtype) = "github.com/babylonlabs-io/babylon/types.SchnorrEOTSSig" ];
+    // fork_finality_sig is the finality signature to the fork block
+    // where finality signature is an EOTS signature
+    bytes fork_finality_sig = 7 [ (gogoproto.customtype) = "github.com/babylonlabs-io/babylon/types.SchnorrEOTSSig" ];
+}
+
 // QueryEvidenceResponse is the response type for the
 // Query/Evidence RPC method.
 message QueryEvidenceResponse {
-  Evidence evidence = 1;
+  EvidenceResponse evidence = 1;
 }
 
 // QueryListEvidencesRequest is the request type for the
@@ -217,7 +240,7 @@ message QueryListEvidencesRequest {
 // Query/ListEvidences RPC method.
 message QueryListEvidencesResponse {
   // blocks is the list of evidences
-  repeated Evidence evidences = 1;
+  repeated EvidenceResponse evidences = 1;
 
   // pagination defines the pagination in the response.
   cosmos.base.query.v1beta1.PageResponse pagination = 2;

x/finality/keeper/grpc_query.go

@@ -178,7 +178,7 @@ func (k Keeper) Evidence(ctx context.Context, req *types.QueryEvidenceRequest) (
 	}
 
 	resp := &types.QueryEvidenceResponse{
-		Evidence: evidence,
+		Evidence: convertToEvidenceResponse(evidence),
 	}
 	return resp, nil
 }
@@ -220,7 +220,7 @@ func (k Keeper) ListEvidences(ctx context.Context, req *types.QueryListEvidences
 	}
 
 	resp := &types.QueryListEvidencesResponse{
-		Evidences:  evidences,
+		Evidences:  convertToEvidenceListResponse(evidences),
 		Pagination: pageRes,
 	}
 	return resp, nil
@@ -290,3 +290,24 @@ func convertToSigningInfosResponse(signInfos []types.FinalityProviderSigningInfo
 	}
 	return response
 }
+
+func convertToEvidenceResponse(evidence *types.Evidence) *types.EvidenceResponse {
+	return &types.EvidenceResponse{
+		FpBtcPkHex:           evidence.FpBtcPk.MarshalHex(),
+		BlockHeight:          evidence.BlockHeight,
+		PubRand:              evidence.PubRand,
+		CanonicalAppHash:     evidence.CanonicalAppHash,
+		ForkAppHash:          evidence.ForkAppHash,
+		CanonicalFinalitySig: evidence.CanonicalFinalitySig,
+		ForkFinalitySig:      evidence.ForkFinalitySig,
+	}
+}
+
+func convertToEvidenceListResponse(evidences []*types.Evidence) []*types.EvidenceResponse {
+	response := make([]*types.EvidenceResponse, len(evidences))
+	for i, evidence := range evidences {
+		resp := convertToEvidenceResponse(evidence)
+		response[i] = resp
+	}
+	return response
+}

x/finality/keeper/grpc_query_test.go

@@ -298,8 +298,8 @@ func FuzzQueryEvidence(f *testing.F) {
 			require.Nil(t, evidenceResp)
 		} else {
 			require.NoError(t, err)
-			require.Equal(t, randomFirstSlashableEvidence, evidenceResp.Evidence)
-			require.True(t, evidenceResp.Evidence.IsSlashable())
+			require.Equal(t, randomFirstSlashableEvidence, convertToEvidence(evidenceResp.Evidence))
+			require.True(t, convertToEvidence(evidenceResp.Evidence).IsSlashable())
 		}
 	})
 }
@@ -361,9 +361,10 @@ func FuzzListEvidences(f *testing.F) {
 		require.NoError(t, err)
 		require.LessOrEqual(t, len(resp.Evidences), int(limit))     // check if pagination takes effect
 		require.EqualValues(t, resp.Pagination.Total, numEvidences) // ensure evidences before startHeight are not included
-		for _, actualEvidence := range resp.Evidences {
-			require.Equal(t, evidences[actualEvidence.FpBtcPk.MarshalHex()].CanonicalAppHash, actualEvidence.CanonicalAppHash)
-			require.Equal(t, evidences[actualEvidence.FpBtcPk.MarshalHex()].ForkAppHash, actualEvidence.ForkAppHash)
+		for _, actualEvidenceResponse := range resp.Evidences {
+			actualEvidence := convertToEvidence(actualEvidenceResponse)
+			expectedEvidence := evidences[actualEvidenceResponse.FpBtcPkHex]
+			require.Equal(t, expectedEvidence, actualEvidence)
 		}
 	})
 }
@@ -436,3 +437,19 @@ func FuzzSigningInfo(f *testing.F) {
 		}
 	})
 }
+
+func convertToEvidence(er *types.EvidenceResponse) *types.Evidence {
+	fpBtcPk, err := bbn.NewBIP340PubKeyFromHex(er.FpBtcPkHex)
+	if err != nil {
+		return nil
+	}
+	return &types.Evidence{
+		FpBtcPk:              fpBtcPk,
+		BlockHeight:          er.BlockHeight,
+		PubRand:              er.PubRand,
+		CanonicalAppHash:     er.CanonicalAppHash,
+		ForkAppHash:          er.ForkAppHash,
+		CanonicalFinalitySig: er.CanonicalFinalitySig,
+		ForkFinalitySig:      er.ForkFinalitySig,
+	}
+}