verify timeout from epochInfo instead of snap.NextEpochCandidates

Author: wanwiset25

consensus/XDPoS/engines/engine_v2/timeout.go

@@ -20,20 +20,21 @@ func (x *XDPoS_v2) VerifyTimeoutMessage(chain consensus.ChainReader, timeoutMsg
 		log.Debug("[VerifyTimeoutMessage] Disqualified timeout message as the proposed round does not match currentRound", "timeoutHash", timeoutMsg.Hash(), "timeoutRound", timeoutMsg.Round, "currentRound", x.currentRound)
 		return false, nil
 	}
-	snap, err := x.getSnapshot(chain, timeoutMsg.GapNumber, true)
-	if err != nil || snap == nil {
-		log.Error("[VerifyTimeoutMessage] Fail to get snapshot when verifying timeout message!", "messageGapNumber", timeoutMsg.GapNumber, "err", err)
+	
+	epochInfo, err := x.getEpochSwitchInfo(chain, chain.CurrentHeader(), chain.CurrentHeader().Hash())
+	if err != nil {
 		return false, err
 	}
-	if len(snap.NextEpochCandidates) == 0 {
+
+	if len(epochInfo.Masternodes) == 0 {
 		log.Error("[VerifyTimeoutMessage] cannot find NextEpochCandidates from snapshot", "messageGapNumber", timeoutMsg.GapNumber)
 		return false, errors.New("empty master node lists from snapshot")
 	}
 
 	verified, signer, err := x.verifyMsgSignature(types.TimeoutSigHash(&types.TimeoutForSign{
 		Round:     timeoutMsg.Round,
 		GapNumber: timeoutMsg.GapNumber,
-	}), timeoutMsg.Signature, snap.NextEpochCandidates)
+	}), timeoutMsg.Signature, epochInfo.Masternodes)
 
 	if err != nil {
 		log.Warn("[VerifyTimeoutMessage] cannot verify timeout signature", "err", err)
@@ -157,16 +158,6 @@ func (x *XDPoS_v2) verifyTC(chain consensus.ChainReader, timeoutCert *types.Time
 		return utils.ErrInvalidTC
 	}
 
-	snap, err := x.getSnapshot(chain, timeoutCert.GapNumber, true)
-	if err != nil {
-		log.Error("[verifyTC] Fail to get snapshot when verifying TC!", "tcGapNumber", timeoutCert.GapNumber)
-		return fmt.Errorf("[verifyTC] Unable to get snapshot, %s", err)
-	}
-	if snap == nil || len(snap.NextEpochCandidates) == 0 {
-		log.Error("[verifyTC] Something wrong with the snapshot from gapNumber", "messageGapNumber", timeoutCert.GapNumber, "snapshot", snap)
-		return errors.New("empty master node lists from snapshot")
-	}
-
 	signatures, duplicates := UniqueSignatures(timeoutCert.Signatures)
 	if len(duplicates) != 0 {
 		for _, d := range duplicates {
@@ -199,7 +190,7 @@ func (x *XDPoS_v2) verifyTC(chain consensus.ChainReader, timeoutCert *types.Time
 	for _, signature := range signatures {
 		go func(sig types.Signature) {
 			defer wg.Done()
-			verified, _, err := x.verifyMsgSignature(signedTimeoutObj, sig, snap.NextEpochCandidates)
+			verified, _, err := x.verifyMsgSignature(signedTimeoutObj, sig, epochInfo.Masternodes)
 			if err != nil || !verified {
 				log.Error("[verifyTC] Error or verification failure", "signature", sig, "error", err)
 				mutex.Lock() // Lock before accessing haveError