da validation

block/slvalidator.go

@@ -47,6 +47,15 @@ func NewSettlementValidator(logger types.Logger, blockManager *Manager) *Settlem
 func (v *SettlementValidator) ValidateStateUpdate(batch *settlement.ResultRetrieveBatch) error {
 	v.logger.Debug("validating state update", "start height", batch.StartHeight, "end height", batch.EndHeight)
 
+	// validate da in state update matches rollapp param
+	daClient, err := v.blockManager.Store.LoadDA(batch.EndHeight)
+	if err != nil {
+		return err
+	}
+	if daClient != string(batch.MetaData.Client) {
+		return types.NewErrStateUpdateDAFraud(batch.StateIndex, batch.EndHeight, daClient, string(batch.MetaData.Client))
+	}
+
 	// loads blocks applied from P2P, if any.
 	p2pBlocks := make(map[uint64]*types.Block)
 	for height := batch.StartHeight; height <= batch.EndHeight; height++ {
@@ -102,7 +111,7 @@ func (v *SettlementValidator) ValidateStateUpdate(batch *settlement.ResultRetrie
 	}
 
 	// validate DA blocks against the state update
-	err := v.ValidateDaBlocks(batch, daBlocks)
+	err = v.ValidateDaBlocks(batch, daBlocks)
 	if err != nil {
 		return err
 	}

store/storeIface.go

@@ -94,6 +94,8 @@ type Store interface {
 
 	SaveDRSVersion(height uint64, version uint32, batch KVBatch) (KVBatch, error)
 
+	LoadDA(height uint64) (string, error)
+
 	SaveDA(height uint64, da string, batch KVBatch) (KVBatch, error)
 
 	RemoveBlockCid(height uint64) error

types/errors.go

@@ -676,3 +676,31 @@ func (e ErrStateUpdateDRSVersionFraud) Error() string {
 func (e ErrStateUpdateDRSVersionFraud) Unwrap() error {
 	return gerrc.ErrFault
 }
+
+// ErrStateUpdateDAFraud represents an error where the DA used in the state update does not follow rollapp param.
+type ErrStateUpdateDAFraud struct {
+	StateIndex uint64
+	Height     uint64
+	DA         string
+	DAFraud    string
+}
+
+func NewErrStateUpdateDAFraud(stateIndex uint64, height uint64, da string, daFraud string) error {
+	return &ErrStateUpdateDAFraud{
+		StateIndex: stateIndex,
+		Height:     height,
+		DA:         da,
+		DAFraud:    daFraud,
+	}
+}
+
+func (e ErrStateUpdateDAFraud) Error() string {
+	return fmt.Sprintf(
+		"possible fraud detected: DA Mismatch - StateIndex: %d, Rollapp DA: %s, State Update DA: %s",
+		e.StateIndex, e.DA, e.DAFraud,
+	)
+}
+
+func (e ErrStateUpdateDAFraud) Unwrap() error {
+	return gerrc.ErrFault
+}