Eventualities need to be binding not just to a plan, yet to the execution of
the plan (the outputs). Bitcoin's Eventuality definition short-cutted this
under a honest multisig assumption, causing the following issue:
If multisig n+1 is verifying multisig n's actions, as detailed in
multi-multisig's document on multisig rotation, it'll check no outstanding
eventualities exist. If we solely bind to the plan, a malicious multisig n
could steal outbound payments yet cause the plan to be marked as successfully
completed.
By modifying the eventuality to also include the expected outputs, this is no
longer possible. Binding to the expected input is preserved in order to remain
binding to the plan (allowing two plans with the same output-set to co-exist).
It was a piece of duplicated data used to achieve context-less
de)serialization. This new Vec code is a bit tricker to first read, yet overall
clean and removes a potential fault.
Saves 2 bytes from DkgShares messages.
See prior commit message for more info.
With the plan for the batch sign ID to be just 5 bytes (potentially 4), this
does incur a +5 bytes cost compared to the ExternalBlock system *even in the
standard case*. The simplicity remains preferred at this time.
The initial TODO was simply to use one ExternalBlock per all batches in the
block. This would require publishing ExternalBlock after the last batch,
requiring knowing the last batch. While we could add such a pipeline, it'd
require:
1) Initial preprocesses using a distinct message from BatchPreprocess
2) An additional message sent after all BatchPreprocess are sent
Unfortunately, both would require tweaks to the SubstrateSigner which aren't
worth the complexity compared to the solution here, at least, not at this time.
While this will cause, if a Tributary is signing a block whose total batch data
exceeds 25 kB, to use multiple transactions which could be optimized out by
'better' local data pipelining, that's an extreme edge case. Given the temporal
nature of each Tributary, it's also an acceptable edge.
This does no longer achieve synchrony over external blocks accordingly. While
signed batches have synchrony, as they embed their block hash, batches being
signed don't have cryptographic synchrony on their contents. This means
validators who are eclipsed may produce invalid shares, as they sign a
different batch. This will be introduced in a follow-up commit.
Updates Tributary values to allow 999ms for block processing (from 2s) and
1667ms for latency (up from 1s).
The intent is to resolve#365. I don't know if this will, but it increases the
chances of success and these values should be fine in prod since Tributary is a
post-execution chain (making block procesisng time minimal).
Does embed the dagger of N::block_time() panicking if the block time in ms
doesn't cleanly divide by 1000.
Fixes where ram_scanned is updated in processor. The prior version, while safe,
would redo massive amounts of work during periods of inactivity. It also hit an
undocumented invariant where get_eventuality_completions assumes new blocks,
yet redone work wouldn't have new blocks.
Modifies Monero's generate_blocks to return the hashes of the generated blocks.
We only expect processor messages when we have the relevant Tributary. We
queued Tributary creation, yet then kicked off processor messages. We need to
wait until the Tributary is actually created to kick off processor messages.
* Add in an implementation of BP+ based off the paper, intended for clarity and review
This was done as part of my work on FCMPs from Monero, and is copied from https://github.com/kayabaNerve/full-chain-membership-proofs
* Remove crate structure of BP+
* Remove arithmetic circuit code
* Remove AC/VC generators code
* Remove generator transcript
Monero uses non-transcripted static generators.
* Further trimming of generators
* Remove the single range proof
It's unused by Monero and accordingly unhelpful.
* Work on getting BP+ to compile in its new env
* Correct BP+ folder name
* Further tweaks to get closer to compiling
* Remove the ScalarMatrix file
It's only used for AC proofs
* Compiles, with tests passing
* Lock BP+ to Ed25519 instead of the generic Ciphersuite
* Resolve most warnings in BP+
* Make existing bulletproofs test easier to read
* Further strip generators
* Swap G/H as Monero did
* Replace RangeCommitment with Commitment
* Hard-code BP+ h to Ed25519's generator
* Use pub(crate) for BP+, not pub
* Replace initial_transcript with hash_plus
* Rename hash_plus to initial_transcript
* Finish integrating the FCMP BP+ impl
* Move BP+ folder
* Correct no-std support
* Rename "long_n" to eta
* Add note on non-prime order dfg points
Prior to the previous commit, whatever async scheduling occurred caused them to
all have the same tip. Now, some are one block ahead of others. This adds
tolerance for that, as it's an acceptable variance, so long as it's solely one
block.
They used &mut self to prevent execution at the same time. This uses a lock
over the channel to achieve the same security, without requiring a lock over
the entire tributary.
This fixes post-provided Provided transactions. sync_block waited for the TX to
be provided, yet it never would as sync_block held a mutable reference over the
entire Tributary, preventing any other read/write operations of any scope.
A timeout increased (bc2f23f72b) due to this bug
not being identified has been decreased back, thankfully.
Also shims in basic support for Completed, which was the WIP before this bug
was identified.
This should be egregious unless the GitHub CI is so inperformant it's breaking
Tendermint consensus's synchrony expectations, which likely points to our own
code being unviable.
This solely serves as an immediate fix to the problem, not a justification of
the unevaluated performance.
Putting a signer first doesn't work because signers can only publish once a
supermajority sync. Now, the code uses an excluded signer (instead of an
included signer) to determine signing set.
Further simplifications are available. Also adds accurate documentation on
latency/sleep reasoning.
