When we receive messages, we're provided with a message ID we can use to
prevent handling an item multiple times. That doesn't prevent us from *sending*
an item multiple times though. Thanks to the UID system, we can now not send if
already present.
Alternatively, we can remove the ordered message ID for just the UID, allowing
duplicates to be sent without issue, and handled on the receiving end.
When a Substrate block occurs, the coordinator is expected to emit
SubstrateBlock. This causes the processor to begin a variety of plans. The
processor now emits SubstrateBlockAck, explicitly listing all plan IDs, before
starting signing.
This lets the coordinator provide a SubstrateBlock transaction, and with it,
recognize all plan IDs as valid.
Prior, we would've had to have a spotty algorithm based upon the upcoming
Preprocess messages, or if we immediately provided the SubstrateBlock
transaction, then wait for the processor to inform us of the contained plans.
This creates an explicitly proper async flow not reliant on waiting for data
availability.
Alternatively, we could've replaced Preprocess with (Block, Vec<Preprocess>).
This would've been more efficient, yet also clunky due to the multiple usages
of the Preprocess message.
There is the ability to cause state bloat by flooding Tributary.
KeyGen/Sign specifically shouldn't allow bloat since we check the
commitments/preprocesses/shares for validity. Accordingly, any invalid data
(such as bloat) should be detected.
It was posssible to place bloat after the valid data. Doing so would be
considered a valid KeyGen/Sign message, yet could add up to 50k kB per sign.
[0; 32] is a magic for no block has been set yet due to this being the first
key pair. If [0; 32] is the latest finalized block, the processor determines
an activation block based on timestamps.
This doesn't use an Option for ergonomic reasons.
It originally wasn't an enum so software which had yet to update before an
integration wouldn't error (as now enums are strictly typed). The strict typing
is preferable though.
SubstrateBlock's provision of the most recently acknowledged block has
equivalent information with the same latency. Accordingly, there's no need for
it.
Clearly establishes why consistency is guaranteed from a Rust borrow-checker
mindset. While there are plenty of... 'violations', they're clearly explained.
Hopefully, this method of thinking helps promote/ensure consistency in the
future.
The signing set should be the first group to submit preprocesses to Tributary.
Re-attempts shouldn't be once every 30s, yet n blocks since the last relevant
message.
Removes the use of an async task/channel in the signer (and Substrate signer).
Also removes the need to be able to get the time from a coin's block, which was
a fragile system marked with a TODO already.
While Bitcoin practically doesn't have long re-orgs, it is possible for a
single miner to build a long chain. Recently, a miner found 5 blocks in a row,
which would be enough to re-org a transaction Serai considered finalized.
* Partial move to ff 0.13
It turns out the newly released k256 0.12 isn't on ff 0.13, preventing further
work at this time.
* Update all crates to work on ff 0.13
The provided curves still need to be expanded to fit the new API.
* Finish adding dalek-ff-group ff 0.13 constants
* Correct FieldElement::product definition
Also stops exporting macros.
* Test most new parts of ff 0.13
* Additionally test ff-group-tests with BLS12-381 and the pasta curves
We only tested curves from RustCrypto. Now we test a curve offered by zk-crypto,
the group behind ff/group, and the pasta curves, which is by Zcash (though
Zcash developers are also behind zk-crypto).
* Finish Ed448
Fully specifies all constants, passes all tests in ff-group-tests, and finishes moving to ff-0.13.
* Add RustCrypto/elliptic-curves to allowed git repos
Needed due to k256/p256 incorrectly defining product.
* Finish writing ff 0.13 tests
* Add additional comments to dalek
* Further comments
* Update ethereum-serai to ff 0.13
Moves the processor to it. This ends up as a net-neutral LoC change to the
processor, unfortunately, yet this makes bitcoin-serai safer/easier to use, and
increases the processor's usage of bitcoin-serai.
Also re-organizes bitcoin-serai a bit.
I'm really unhappy with a cfg(test) within the codebase. The double checking of
it makes it tolerable though, especially when compared to dropping these tests.
