Ensure that validators sign with a frozen UTXO

[bosagora]

Ensure that validators sign with a frozen UTXO

[Geod24]

Where signature by Validators means signature of BlockHeader

Yes

Does frozen UTXO check the UTXO of the enrollment K (UTXO key) ?

That's a different issue

[AndrejMitrovic]

This issue #205 only deals with the validation part of a block.

So if we have a block header which is signed, in order to validate the block then the signature must be checked. We need to make sure:

• The signature is actually valid.
• The key it was signed with belongs to a node that has frozen 40,000 Boa. If the node hasn't frozen 40,000 Boa then it has no right to sign the block, therefore the block is invalid.
• The height of the block that contains the signature of a node, it must be at least N blocks after the block height where the node staked 40,000 Boa. The "N" is defined in the Yellow paper. So, a node first freezes UTXO, then after N blocks it can start signing blocks.
• If the UTXOs for that node are actually melting, the signature is considered invalid.

I suggest implementing this issue #205 in several steps, depending on what kind of approach you want to take:

• At first, assume the block header can only contain one validator signature. This makes it easy to implement the checks for the frozen UTXO. You could just store a PublicKey validator; Signature signature; in the block header, and change isInvalidReason for blocks so that it tests the conditions that I listed in the previous paragraph (see also the Definition of Done).
• Then, if that works, try to extend your function so it works with multiple signatures. For example, you could write struct ValidatorSigs { PublicKey key; Signature sig; } and add that to the block header struct BlockHeader { ValidatorSigs[] validator_sigs; }. For example, all the signatures in the block header must be valid. As soon as one is invalid, the block is rejected.

Then later, once #365 and #406 are implemented, we can adapt your solution and change the block header so it works with the Schnorr signature scheme and with the Enrollment process.

If that doesn't help, I can only suggest waiting for input from @Geod24.

[Geod24]

Depends on #204

[Geod24]

Unblocked

[TrustHenry]

I need to make sure that signatures by validators are done using a frozen UTXO in order to make sure the validator has stake in the system.

Where signature by Validators means signature of BlockHeader or enrollment.S ?
Does frozen UTXO check the UTXO of the enrollment K (UTXO key) ?

[TrustHenry]

When a block is received or signed
Validators signed BitField...
The frozen UTXO shall be found and verified in utxo_db?

[TrustHenry]

A melting UTXO cannot sign blocks

a melting UTXO cannot sign blocks" The requirements should be deleted.

Frozen UTXO can sign the block as a validator up to the "freezing period / 2" block during the transaction occurring and melting period.

[TrustHenry]

ping @Geod24