consortium/v2: add function to get seal hash before finality vote

As we delay assembling finality vote until Seal function, it means the seal hash
can be updated after the FinalizeAndAssemble. This breaks the worker which uses
seal hash to store and look up seal tasks between FinalizeAndAssemble and Seal
function. This commit creates a function SealHashBeforeFinalityVote to calculate
the seal hash before assembling finality vote to be used by worker to look up
the seal tasks.

consensus/consensus.go

@@ -166,6 +166,8 @@ type FastFinalityPoSA interface {
 	SetVotePool(votePool VotePool)
 
 	GetActiveValidatorAt(chain ChainHeaderReader, blockNumber uint64, blockHash common.Hash) []finality.ValidatorWithBlsPub
+
+	SealHashBeforeFinalityVote(header *types.Header) common.Hash
 }
 
 type VotePool interface {

consensus/consortium/main.go

@@ -143,6 +143,15 @@ func (c *Consortium) SealHash(header *types.Header) common.Hash {
 	return c.v1.SealHash(header)
 }
 
+// SealHashBeforeFinalityVote returns the seal hash before assembling finality vote
+// this is use for worker to look up seal tasks
+func (c *Consortium) SealHashBeforeFinalityVote(header *types.Header) common.Hash {
+	if c.chainConfig.IsShillin(header.Number) {
+		return c.v2.SealHashBeforeFinalityVote(header)
+	}
+	return c.SealHash(header)
+}
+
 // Close implements consensus.Engine. It's a noop for Consortium as there are no background threads.
 func (c *Consortium) Close() error {
 	return nil

consensus/consortium/v2/consortium.go

@@ -1023,6 +1023,17 @@ func (c *Consortium) SealHash(header *types.Header) common.Hash {
 	return SealHash(header, c.chainConfig.ChainID)
 }
 
+// SealHashBeforeFinalityVote returns the seal hash before assembling finality vote
+// this is use for worker to look up seal tasks
+func (c *Consortium) SealHashBeforeFinalityVote(header *types.Header) common.Hash {
+	copyHeader := types.CopyHeader(header)
+
+	extraData, _ := finality.DecodeExtra(copyHeader.Extra, true)
+	extraData.HasFinalityVote = 0
+	copyHeader.Extra = extraData.Encode(true)
+	return SealHash(copyHeader, c.chainConfig.ChainID)
+}
+
 // Close implements consensus.Engine. It's a noop for Consortium as there are no background threads.
 func (c *Consortium) Close() error {
 	return nil

miner/worker.go

@@ -675,9 +675,15 @@ func (w *worker) resultLoop() {
 				continue
 			}
 			var (
-				sealhash = w.engine.SealHash(block.Header())
+				sealhash common.Hash
 				hash     = block.Hash()
 			)
+			if engine, ok := w.engine.(consensus.FastFinalityPoSA); ok {
+				sealhash = engine.SealHashBeforeFinalityVote(block.Header())
+			} else {
+				sealhash = w.engine.SealHash(block.Header())
+			}
+
 			w.pendingMu.RLock()
 			task, exist := w.pendingTasks[sealhash]
 			w.pendingMu.RUnlock()