Implement NotaryAssisted transaction attribute

[AnnaShaleva]

Description

Close #2896. Use a stub for native Notary contract hash since this contract is not implemented yet. Thus, technically, NotaryAssisted attribute verification will always fail on real network until native Notary is implemented.

Type of change

• New feature (non-breaking change which adds functionality)

How Has This Been Tested?

• A group of unit tests for NotaryAssisted attribute.

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules:
  • Add NotaryAssisted transaction attribute type neo-devpack-dotnet#983
  • Add NotaryAssisted transaction attribute type neo-modules#884

[AnnaShaleva]

I'm not allowed to request review, set labels or resolve conversations. Maybe someone from neo-project with access rights can allow me at least to request review?

[shargon]

I'm not allowed to request review, set labels or resolve conversations. Maybe someone from neo-project with access rights can allow me at least to request review?

You didn't accept your role xD, I sent you an invitation time ago... Time to review your email? 😄

[Jim8y]

Hi @AnnaShaleva , we are trying to add as much comments in the core as possible, may you please add comments to explain CalculateNetworkFee.

[AnnaShaleva]

may you please add comments to explain CalculateNetworkFee.

Sure, fixed.

[roman-khimov]

GAS.OnPersist change is missing for the attribute.

[AnnaShaleva]

GAS.OnPersist change is missing for the attribute.

Completely forgot about it, fixed.

[vncoelho]

Maybe this PR we merge after next release.

[AnnaShaleva]

Maybe this PR we merge after next release.

This PR doesn't hurt because currently in real network NotaryAssisted attribute is always invalid since transaction must have Notary contract as a signer, and Notary contract is not implemented yet.

Thus, I vote to merge it before 3.7. What do you think?

[roman-khimov]

It goes step by step, @vncoelho. What this delay would buy us? The attribute logic is rather simple on its own.

[shargon]

I need more time to review the notary proposal, honestly, I didn't expect it to be merged in 3.7 and it is already beginning to produce changes in the core

[vncoelho]

For me is good if this was implemented

@shargon, the test is added, it works as expected. Please, check out the 6705469.

@Jim8y @vncoelho @cschuchardt88 and everyone interested, we need to move on with this PR. Please, consider reviewing it.

I am aligned with @vang1ong7ang and I will wait until his recommendations are all clarified.

[AnnaShaleva]

I am aligned with @vang1ong7ang and I will wait until his recommendations are all clarified.

@vncoelho, @vang1ong7ang There are replies (#3175 (comment), #3175 (comment)), so could you please specify the exact questions/issues/possible vector of attack that you have in mind right now? So that we can answer properly.

[AnnaShaleva]

@neo-project/core, let's try to review one more time, if you have any specific test cases or a possible vector of attack on your mind, then please, comment. This PR is ready for review and may be included into 3.8.0.

[roman-khimov]

@AnnaShaleva, now with neo-modules integrated we also need changes from neo-project/neo-modules#884 here.

[AnnaShaleva]

need changes from neo-project/neo-modules#884 here.

Sure, will port it ASAP.

[AnnaShaleva]

Also need to move Policy update under Domovoi hardfork to keep our states unchanged, depends on #3290.

[cschuchardt88]

Fix all the warning please

XML comment has badly formed XML -- 'Missing equals sign between attribute and attribute value.'

[AnnaShaleva]

We've checked that NeoFS networks are 100% compatible with both Notary contract and NotaryAssisted attribute enabled starting from D hardfork (see the nspcc-dev/neo-go#3465). It means that Notary contract and NotaryAssisted attribute implementation won't change the existing node state. In the last commit I've moved NotaryAssisted attribute under D hardfork.

Fix all the warning please

Thank you, fixed!

[AnnaShaleva]

UPD: we're aware of the Technical Committee decision to postpone the Notary subsystem implementation. However, we think that it's good to keep this code up-to-date wrt the current master so that it'll be easier for us to review and merge it once the time comes. Hence, I've updated the code to the latest master and moved the NotaryAssisted attribute under the next available hardfork (HF_Echidna).