Confirm DKG start before triggering off-chain protocol #3468
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So far, the tECDSA DKG was triggered using a simple event listener acting on `DKGStarted` events. However, small chain reorgs may cause different `startBlock` to be received by DKG participants. That can lead to invalid signatures over the produced DKG result as the `startBlock` is one of the signature's components. Here we improve that by adding a confirmation mechanism that delays the start of the off-chain protocol until the event and DKG on-chain state is confirmed.
The off-chain protocol should be started as close as possible to the current block or even further. Starting the off-chain protocol with a past block will likely cause a failure of the first attempt as the start block is used to synchronize the announcements and the state machine. Here we ensure a proper start point by delaying the execution by the confirmation period length.
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I can't test this code given #3460 is not yet finished and I am struggling to set up the environment. If you performed tests locally @lukasz-zimnoch I will trust your verification and merge the PR once the code comments are addressed. We will deploy it to testnet for another verification as well.
I have tested the basic scenario: request a new wallet to trigger DKG, wait until the confirmation period elapses, and check if nodes executed the protocol as expected. The corner cases involving reorgs and event duplicates must be checked on testnet |
Closes: #3456
So far, the tECDSA DKG was triggered using a simple event listener acting on
DKGStartedevents. However, small chain reorgs may cause differentstartBlockto be received by DKG participants. That can lead to invalid signatures over the produced DKG result as thestartBlockis one of the signature's components. Here we improve that by adding a confirmation mechanism that delays the start of the off-chain protocol until the event and DKG on-chain state is confirmed. This way clients are sure to use a finalized event that will no longer be the subject of chain reorgs.