Contract redirectiton

[doubiliu]

Contract redirectiton.Draft

[eryeer]

Great work guy! Congratulations.

[vncoelho]

Any other idea for the name of this variable?

[doubiliu]

Is preFix well? @vncoelho

[Tommo-L]

How about renaming the ScriptHash to ContractHash, PreDataKey to NameSpace, Preifx, or StorageKeyPrefix ?

[erikzhang]

I rethought it a bit. I don't think we should use script hash as a storage key anymore. Maybe we should use GUID from the beginning. This eliminates the need for redirection.

[doubiliu]

@erikzhang Hi,大佬. Can you describe the logic for generating the GUID?If you use a random number, it means that when you send the contract TX, you have to add this field to the transaction or contract properties, and you have to do the check.

[erikzhang]

The GUID is a local value. It is used in local database, and is not on chain.

We can create a GUID when deploying a contract. Each contract has a unique (but not global) GUID, and then the contract's storage is prefixed with that GUID.

[eryeer]

Does it mean that each node generates its own Guid when creating a contract? If so how to ensure that the Guid generated by each node is the same? Otherwise, the state of each Storage will be different, and the state root will be different too.

[doubiliu]

I agree with @eryeer , we need to maintain the consistency of each node. If we cannot guarantee that the GUID of each node is consistent, then the influence of GUID needs to be removed in the calculation of stateroot or some other places. @erikzhang

[erikzhang]

There are many ways to create deterministic GUIDs.

[doubiliu]

But if we use a deterministic GUID, it is not much different from scripthash. @erikzhang

[erikzhang]

Here is an example: #1400

[erikzhang]

But if we use a deterministic GUID, it is not much different from scripthash.

The main difference is that with the GUID you don't need to add redirection records, and the contract can be upgraded any times without recording additional information to prevent old contracts from being redeployed. Because if an old contract is deployed, a new GUID is created.

[doubiliu]

@erikzhang

            internal static Guid GetDeterministicGuid(Transaction tx, uint nonce)
            {
                return new Guid(Concat(tx.Hash.ToArray(), BitConverter.GetBytes(nonce)).Sha256().AsSpan(0, 16));
            }

Maybe it is not safe here.We can attack the storage area of ​​a contract by means of hash collision.

[erikzhang]

@doubiliu Please discuss at #1400

[doubiliu]

OK.Got it.