With a DKG removal comes a reduction in the amount of participants which was
ignored by re-attempts.
Now, we determine n/i based on the parties removed, and deterministically
obtain the context of who was removd.
* Schedule re-attempts and add a (not filled out) match statement to actually execute them
A comment explains the methodology. To copy it here:
"""
This is because we *always* re-attempt any protocol which had participation. That doesn't
mean we *should* re-attempt this protocol.
The alternatives were:
1) Note on-chain we completed a protocol, halting re-attempts upon 34%.
2) Vote on-chain to re-attempt a protocol.
This schema doesn't have any additional messages upon the success case (whereas
alternative #1 does) and doesn't have overhead (as alternative #2 does, sending votes and
then preprocesses. This only sends preprocesses).
"""
Any signing protocol which reaches sufficient participation will be
re-attempted until it no longer does.
* Have the Substrate scanner track DKG removals/completions for the Tributary code
* Don't keep trying to publish a participant removal if we've already set keys
* Pad out the re-attempt match a bit more
* Have CosignEvaluator reload from the DB
* Correctly schedule cosign re-attempts
* Actuall spawn new DKG removal attempts
* Use u32 for Batch ID in SubstrateSignableId, finish Batch re-attempt routing
The batch ID was an opaque [u8; 5] which also included the network, yet that's
redundant and unhelpful.
* Clarify a pair of TODOs in the coordinator
* Remove old TODO
* Final comment cleanup
* Correct usage of TARGET_BLOCK_TIME in reattempt scheduler
It's in ms and I assumed it was in s.
* Have coordinator tests drop BatchReattempts which aren't relevant yet may exist
* Bug fix and pointless oddity removal
We scheduled a re-attempt upon receiving 2/3rds of preprocesses and upon
receiving 2/3rds of shares, so any signing protocol could cause two re-attempts
(not one more).
The coordinator tests randomly generated the Batch ID since it was prior an
opaque byte array. While that didn't break the test, it was pointless and did
make the already-succeeded check before re-attempting impossible to hit.
* Add log statements, correct dead-lock in coordinator tests
* Increase pessimistic timeout on recv_message to compensate for tighter best-case timeouts
* Further bump timeout by a minute
AFAICT, GH failed by just a few seconds.
This also is worst-case in a single instance, making it fine to be decently long.
* Further further bump timeout due to lack of distinct error
* Move logic for evaluating if a cosign should occur to its own file
Cleans it up and makes it more robust.
* Have expected_next_batch return an error instead of retrying
While convenient to offer an error-free implementation, it potentially caused
very long lived lock acquisitions in handle_processor_message.
* Unify and clean DkgConfirmer and DkgRemoval
Does so via adding a new file for the common code, SigningProtocol.
Modifies from_cache to return the preprocess with the machine, as there's no
reason not to. Also removes an unused Result around the type.
Clarifies the security around deterministic nonces, removing them for
saved-to-disk cached preprocesses. The cached preprocesses are encrypted as the
DB is not a proper secret store.
Moves arguments always present in the protocol from function arguments into the
struct itself.
Removes the horribly ugly code in DkgRemoval, fixing multiple issues present
with it which would cause it to fail on use.
* Set SeraiBlockNumber in cosign.rs as it's used by the cosigning protocol
* Remove unnecessary Clone from lambdas in coordinator
* Remove the EventDb from Tributary scanner
We used per-Transaction DB TXNs so on error, we don't have to rescan the entire
block yet only the rest of it. We prevented scanning multiple transactions by
tracking which we already had.
This is over-engineered and not worth it.
* Implement borsh for HasEvents, removing the manual encoding
* Merge DkgConfirmer and DkgRemoval into signing_protocol.rs
Fixes a bug in DkgConfirmer which would cause it to improperly handle indexes
if any validator had multiple key shares.
* Strictly type DataSpecification's Label
* Correct threshold_i_map_to_keys_and_musig_i_map
It didn't include the participant's own index and accordingly was offset.
* Create TributaryBlockHandler
This struct contains all variables prior passed to handle_block and stops them
from being passed around again and again.
This also ensures fatal_slash is only called while handling a block, as needed
as it expects to operate under perfect consensus.
* Inline accumulate, store confirmation nonces with shares
Inlining accumulate makes sense due to the amount of data accumulate needed to
be passed.
Storing confirmation nonces with shares ensures that both are available or
neither. Prior, one could be yet the other may not have been (requiring an
assert in runtime to ensure we didn't bungle it somehow).
* Create helper functions for handling DkgRemoval/SubstrateSign/Sign Tributary TXs
* Move Label into SignData
All of our transactions which use SignData end up with the same common usage
pattern for Label, justifying this.
Removes 3 transactions, explicitly de-duplicating their handlers.
* Remove CurrentlyCompletingKeyPair for the non-contextual DkgKeyPair
* Remove the manual read/write for TributarySpec for borsh
This struct doesn't have any optimizations booned by the manual impl. Using
borsh reduces our scope.
* Use temporary variables to further minimize LoC in tributary handler
* Remove usage of tuples for non-trivial Tributary transactions
* Remove serde from dkg
serde could be used to deserialize intenrally inconsistent objects which could
lead to panics or faults.
The BorshDeserialize derives have been replaced with a manual implementation
which won't produce inconsistent objects.
* Abstract Future generics using new trait definitions in coordinator
* Move published_signed_transaction to tributary/mod.rs to reduce the size of main.rs
* Split coordinator/src/tributary/mod.rs into spec.rs and transaction.rs
