[backport] chore: Allow running of jailed fp (#260) (#265)

Closes #259. This allows jailed fps to still be able to send randomness
and it could start voting immdiately after unjailing.

CHANGELOG.md

@@ -40,6 +40,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 ### Improvements
 
 * [#253](https://github.com/babylonlabs-io/finality-provider/issues/253) Refactor to start from the last finalized height
+* [#260](https://github.com/babylonlabs-io/finality-provider/pull/260) Allow running of jailed fp
 
 ## v0.14.2
 

finality-provider/service/app.go

@@ -544,13 +544,6 @@ func (app *FinalityProviderApp) setFinalityProviderSlashed(fpi *FinalityProvider
 	}
 }
 
-func (app *FinalityProviderApp) setFinalityProviderJailed(fpi *FinalityProviderInstance) {
-	fpi.MustSetStatus(proto.FinalityProviderStatus_JAILED)
-	if err := app.removeFinalityProviderInstance(); err != nil {
-		panic(fmt.Errorf("failed to terminate a jailed finality-provider %s: %w", fpi.GetBtcPkHex(), err))
-	}
-}
-
 // NOTE: this is not safe in production, so only used for testing purpose
 func (app *FinalityProviderApp) getFpPrivKey(fpPk []byte) (*btcec.PrivateKey, error) {
 	record, err := app.eotsManager.KeyRecord(fpPk, "")

finality-provider/service/app_test.go

@@ -210,6 +210,7 @@ func FuzzUnjailFinalityProvider(f *testing.F) {
 		fpCfg := config.DefaultConfigWithHome(fpHomeDir)
 		// use shorter interval for the test to end faster
 		fpCfg.SubmissionRetryInterval = time.Millisecond * 10
+		fpCfg.SignatureSubmissionInterval = time.Millisecond * 10
 
 		blkInfo := &types.BlockInfo{Height: currentHeight}
 
@@ -230,12 +231,17 @@ func FuzzUnjailFinalityProvider(f *testing.F) {
 
 		expectedTxHash := datagen.GenRandomHexStr(r, 32)
 		mockClientController.EXPECT().UnjailFinalityProvider(fpPk.MustToBTCPK()).Return(&types.TxResponse{TxHash: expectedTxHash}, nil)
+		err := app.StartFinalityProvider(fpPk, "")
+		require.NoError(t, err)
+		fpIns, err := app.GetFinalityProviderInstance()
+		require.NoError(t, err)
+		require.True(t, fpIns.IsJailed())
 		res, err := app.UnjailFinalityProvider(fpPk)
 		require.NoError(t, err)
 		require.Equal(t, expectedTxHash, res.TxHash)
-		fpInfo, err := app.GetFinalityProviderInfo(fpPk)
-		require.NoError(t, err)
-		require.Equal(t, proto.FinalityProviderStatus_INACTIVE.String(), fpInfo.GetStatus())
+		require.Eventually(t, func() bool {
+			return !fpIns.IsJailed()
+		}, eventuallyWaitTimeOut, eventuallyPollTime)
 	})
 }
 

finality-provider/service/event_loops.go

@@ -65,12 +65,6 @@ func (app *FinalityProviderApp) monitorCriticalErr() {
 					zap.String("pk", criticalErr.fpBtcPk.MarshalHex()))
 				continue
 			}
-			if errors.Is(criticalErr.err, ErrFinalityProviderJailed) {
-				app.setFinalityProviderJailed(fpi)
-				app.logger.Debug("the finality-provider has been jailed",
-					zap.String("pk", criticalErr.fpBtcPk.MarshalHex()))
-				continue
-			}
 			app.logger.Fatal(instanceTerminatingMsg,
 				zap.String("pk", criticalErr.fpBtcPk.MarshalHex()), zap.Error(criticalErr.err))
 		case <-app.quit:
@@ -177,6 +171,11 @@ func (app *FinalityProviderApp) unjailFpLoop() {
 				zap.String("txHash", res.TxHash),
 			)
 
+			// set the status to INACTIVE by default
+			// the status will be changed to ACTIVE
+			// if it has voting power for the next height
+			app.fps.MustSetFpStatus(req.btcPubKey.MustToBTCPK(), proto.FinalityProviderStatus_INACTIVE)
+
 			req.successResponse <- &UnjailFinalityProviderResponse{
 				TxHash: res.TxHash,
 			}

finality-provider/service/fp_instance.go

@@ -68,8 +68,8 @@ func NewFinalityProviderInstance(
 		return nil, fmt.Errorf("failed to retrieve the finality provider %s from DB: %w", fpPk.MarshalHex(), err)
 	}
 
-	if !sfp.ShouldStart() {
-		return nil, fmt.Errorf("the finality provider instance cannot be initiated with status %s", sfp.Status.String())
+	if sfp.Status == proto.FinalityProviderStatus_SLASHED {
+		return nil, fmt.Errorf("the finality provider instance is already slashed")
 	}
 
 	return newFinalityProviderInstanceFromStore(sfp, cfg, s, prStore, cc, em, metrics, passphrase, errChan, logger)
@@ -109,7 +109,8 @@ func (fp *FinalityProviderInstance) Start() error {
 	}
 
 	if fp.IsJailed() {
-		return fmt.Errorf("%w: %s", ErrFinalityProviderJailed, fp.GetBtcPkHex())
+		fp.logger.Warn("the finality provider is jailed",
+			zap.String("pk", fp.GetBtcPkHex()))
 	}
 
 	startHeight, err := fp.DetermineStartHeight()
@@ -163,7 +164,19 @@ func (fp *FinalityProviderInstance) IsRunning() bool {
 	return fp.isStarted.Load()
 }
 
+// IsJailed returns true if fp is JAILED
+// NOTE: it retrieves the the status from the db to
+// ensure status is up-to-date
 func (fp *FinalityProviderInstance) IsJailed() bool {
+	storedFp, err := fp.fpState.s.GetFinalityProvider(fp.GetBtcPk())
+	if err != nil {
+		panic(fmt.Errorf("failed to retrieve the finality provider %s from db: %w", fp.GetBtcPkHex(), err))
+	}
+
+	if storedFp.Status != fp.GetStatus() {
+		fp.MustSetStatus(storedFp.Status)
+	}
+
 	return fp.GetStatus() == proto.FinalityProviderStatus_JAILED
 }
 
@@ -178,6 +191,15 @@ func (fp *FinalityProviderInstance) finalitySigSubmissionLoop() {
 			if len(pollerBlocks) == 0 {
 				continue
 			}
+
+			if fp.IsJailed() {
+				fp.logger.Warn("the finality-provider is jailed",
+					zap.String("pk", fp.GetBtcPkHex()),
+				)
+
+				continue
+			}
+
 			targetHeight := pollerBlocks[len(pollerBlocks)-1].Height
 			fp.logger.Debug("the finality-provider received new block(s), start processing",
 				zap.String("pk", fp.GetBtcPkHex()),
@@ -198,6 +220,13 @@ func (fp *FinalityProviderInstance) finalitySigSubmissionLoop() {
 			res, err := fp.retrySubmitSigsUntilFinalized(processedBlocks)
 			if err != nil {
 				fp.metrics.IncrementFpTotalFailedVotes(fp.GetBtcPkHex())
+				if errors.Is(err, ErrFinalityProviderJailed) {
+					fp.MustSetStatus(proto.FinalityProviderStatus_JAILED)
+					fp.logger.Debug("the finality-provider has been jailed",
+						zap.String("pk", fp.GetBtcPkHex()))
+
+					continue
+				}
 				if !errors.Is(err, ErrFinalityProviderShutDown) {
 					fp.reportCriticalErr(err)
 				}

finality-provider/store/storedfp.go

@@ -69,17 +69,3 @@ func (sfp *StoredFinalityProvider) ToFinalityProviderInfo() *proto.FinalityProvi
 		Status:          sfp.Status.String(),
 	}
 }
-
-// ShouldStart returns true if the finality provider should start his instance
-// based on the current status of the finality provider.
-//
-// It returns false if the status is either 'REGISTERED', 'JAILED' or 'SLASHED'.
-// It returns true for all the other status.
-func (sfp *StoredFinalityProvider) ShouldStart() bool {
-	if sfp.Status == proto.FinalityProviderStatus_SLASHED ||
-		sfp.Status == proto.FinalityProviderStatus_JAILED {
-		return false
-	}
-
-	return true
-}