Design of a Blockchain-Based Traceability System with a Privacy-Preserving Scheme of Zero-Knowledge Proof

Algorithm 3 VerifyKey generation algorithm.

	Input: PID, TraceabilityFeature(TF), offlineVolume
	Output: witness
(1)	Tx = Datachain.search(PID)
(2)	Hash = Tx.DataHash
(3)	Data = offlineVolume. Find (“PID”)
(4)	For each in TF
(5)	verifyKey.append(Hash(Data) = = Tx.hashData)
(6)	verifyKey.append(PID = = Tx.PID)
(7)	verifyKey.append(Data.satify(TF))
(8)	return verifyKey