* WIP constant-time implementation of the ec-divisors library
* Fix misc logic errors in poly.rs
* Remove accidentally committed test statements
* Fix ConstantTimeEq for CoefficientIndex
* Correct the iterations formula
x**3 / (0 y + x**1) would prior be considered indivisible with iterations = 0.
It is divisible however. The amount of iterations should be the amount of
coefficients within the numerator *excluding the coefficient for y**0 x**0*.
* Poly PartialEq, conditional_select_poly which checks poly structure equivalence
If the first passed argument is smaller than the latter, it's padded to the
necessary length.
Also adds code to trim the remainder as the remainder is the value modulo, so
it's very important it remains concise and workable.
* Fix the line function
It selected the case if both were identity before selecting the case if either
were identity, the latter overwriting the former.
* Final fixes re: ct_get
1) Our quotient structure does need to be of size equal to the numerator
entirely to prevent out-of-bounds reads on it
2) We need to get from yx_coefficients if of length >=, so if the length is 1
we can read y_pow=1 from it. If y_pow=0, and its length is 0 so it has no
inner Vecs, we need to fall back with the guard y_pow != 0.
* Add a trim algorithm to lib.rs to prevent Polys from becoming unbearably gigantic
Our Poly algorithm is incredibly leaky. While it presumably should be improved,
we can take advantage of our known structure while constructing divisors (and
the small modulus) to simply trim out the zero coefficients leaked. This
maintains Polys in a manageable size.
* Move constant-time scalar mul gadget divisor creation from dkg to ec-divisors
Anyone creating a divisor for the scalar mul gadget should use constant time
code, so this code should at least be in the EC gadgets crate It's of
non-trivial complexity to deal with otherwise.
* Remove unsafe, cache timing attacks from ec-divisors
* Upstream GBP, divisor, circuit abstraction, and EC gadgets from FCMP++
* Initial eVRF implementation
Not quite done yet. It needs to communicate the resulting points and proofs to
extract them from the Pedersen Commitments in order to return those, and then
be tested.
* Add the openings of the PCs to the eVRF as necessary
* Add implementation of secq256k1
* Make DKG Encryption a bit more flexible
No longer requires the use of an EncryptionKeyMessage, and allows pre-defined
keys for encryption.
* Make NUM_BITS an argument for the field macro
* Have the eVRF take a Zeroizing private key
* Initial eVRF-based DKG
* Add embedwards25519 curve
* Inline the eVRF into the DKG library
Due to how we're handling share encryption, we'd either need two circuits or to
dedicate this circuit to the DKG. The latter makes sense at this time.
* Add documentation to the eVRF-based DKG
* Add paragraph claiming robustness
* Update to the new eVRF proof
* Finish routing the eVRF functionality
Still needs errors and serialization, along with a few other TODOs.
* Add initial eVRF DKG test
* Improve eVRF DKG
Updates how we calculcate verification shares, improves performance when
extracting multiple sets of keys, and adds more to the test for it.
* Start using a proper error for the eVRF DKG
* Resolve various TODOs
Supports recovering multiple key shares from the eVRF DKG.
Inlines two loops to save 2**16 iterations.
Adds support for creating a constant time representation of scalars < NUM_BITS.
* Ban zero ECDH keys, document non-zero requirements
* Implement eVRF traits, all the way up to the DKG, for secp256k1/ed25519
* Add Ristretto eVRF trait impls
* Support participating multiple times in the eVRF DKG
* Only participate once per key, not once per key share
* Rewrite processor key-gen around the eVRF DKG
Still a WIP.
* Finish routing the new key gen in the processor
Doesn't touch the tests, coordinator, nor Substrate yet.
`cargo +nightly fmt && cargo +nightly-2024-07-01 clippy --all-features -p serai-processor`
does pass.
* Deduplicate and better document in processor key_gen
* Update serai-processor tests to the new key gen
* Correct amount of yx coefficients, get processor key gen test to pass
* Add embedded elliptic curve keys to Substrate
* Update processor key gen tests to the eVRF DKG
* Have set_keys take signature_participants, not removed_participants
Now no one is removed from the DKG. Only `t` people publish the key however.
Uses a BitVec for an efficient encoding of the participants.
* Update the coordinator binary for the new DKG
This does not yet update any tests.
* Add sensible Debug to key_gen::[Processor, Coordinator]Message
* Have the DKG explicitly declare how to interpolate its shares
Removes the hack for MuSig where we multiply keys by the inverse of their
lagrange interpolation factor.
* Replace Interpolation::None with Interpolation::Constant
Allows the MuSig DKG to keep the secret share as the original private key,
enabling deriving FROST nonces consistently regardless of the MuSig context.
* Get coordinator tests to pass
* Update spec to the new DKG
* Get clippy to pass across the repo
* cargo machete
* Add an extra sleep to ensure expected ordering of `Participation`s
* Update orchestration
* Remove bad panic in coordinator
It expected ConfirmationShare to be n-of-n, not t-of-n.
* Improve documentation on functions
* Update TX size limit
We now no longer have to support the ridiculous case of having 49 DKG
participations within a 101-of-150 DKG. It does remain quite high due to
needing to _sign_ so many times. It'd may be optimal for parties with multiple
key shares to independently send their preprocesses/shares (despite the
overhead that'll cause with signatures and the transaction structure).
* Correct error in the Processor spec document
* Update a few comments in the validator-sets pallet
* Send/Recv Participation one at a time
Sending all, then attempting to receive all in an expected order, wasn't working
even with notable delays between sending messages. This points to the mempool
not working as expected...
* Correct ThresholdKeys serialization in modular-frost test
* Updating existing TX size limit test for the new DKG parameters
* Increase time allowed for the DKG on the GH CI
* Correct construction of signature_participants in serai-client tests
Fault identified by akil.
* Further contextualize DkgConfirmer by ValidatorSet
Caught by a safety check we wouldn't reuse preprocesses across messages. That
raises the question of we were prior reusing preprocesses (reusing keys)?
Except that'd have caused a variety of signing failures (suggesting we had some
staggered timing avoiding it in practice but yes, this was possible in theory).
* Add necessary calls to set_embedded_elliptic_curve_key in coordinator set rotation tests
* Correct shimmed setting of a secq256k1 key
* cargo fmt
* Don't use `[0; 32]` for the embedded keys in the coordinator rotation test
The key_gen function expects the random values already decided.
* Big-endian secq256k1 scalars
Also restores the prior, safer, Encryption::register function.
1) Removes the key image DLEq on the Monero side of things, as the produced
signature share serves as a DLEq for it.
2) Removes the nonce DLEqs from modular-frost as they're unnecessary for
monero-serai. Updates documentation accordingly.
Without the proof the nonces are internally consistent, the produced signatures
from modular-frost can be argued as a batch-verifiable CP93 DLEq (R0, R1, s),
or as a GSP for the CP93 DLEq statement (which naturally produces (R0, R1, s)).
The lack of proving the nonces consistent does make the process weaker, yet
it's also unnecessary for the class of protocols this is intended to service.
To provide DLEqs for the nonces would be to provide PoKs for the nonce
commitments (in the traditional Schnorr case).
* 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
* Add SignalsConfig to chain_spec
* Correct multiexp feature flagging for rand_core std
* Remove bincode for borsh
Replaces a non-canonical encoding with a canonical encoding which additionally
should be faster.
Also fixes an issue where we used bincode in transcripts where it cannot be
trusted.
This ended up fixing a myriad of other bugs observed, unfortunately.
Accordingly, it either has to be merged or the bug fixes from it must be ported
to a new PR.
* Make serde optional, minimize usage
* Make borsh an optional dependency of substrate/ crates
* Remove unused dependencies
* Use [u8; 64] where possible in the processor messages
* Correct borsh feature flagging
Resolves#391.
Given this code already wasn't modular/composable, this should be overall
equivalent regarding functionality and security. It's much less opinionated
though and has fewer dependencies.
* Have processor report errors during the DKG to the coordinator
* Add RemoveParticipant, InvalidDkgShare to coordinator
* Route DKG blame around coordinator
* Allow public construction of AdditionalBlameMachine
Necessary for upcoming work on handling DKG blame in the processor and
coordinator.
Additionally fixes a publicly reachable panic when commitments parsed with one
ThresholdParams are used in a machine using another set of ThresholdParams.
Renames InvalidProofOfKnowledge to InvalidCommitments.
* Remove unused error from dleq
* Implement support for VerifyBlame in the processor
* Have coordinator send the processor share message relevant to Blame
* Remove desync between processors reporting InvalidShare and ones reporting GeneratedKeyPair
* Route blame on sign between processor and coordinator
Doesn't yet act on it in coordinator.
* Move txn usage as needed for stable Rust to build
* Correct InvalidDkgShare serialization
If a crate has std set, it should enable std for all dependencies in order to
let them properly select which algorithms to use. Some crates fallback to
slower/worse algorithms on no-std.
Also more aggressively sets default-features = false leading to a *10%*
reduction in the amount of crates coordinator builds.
* dalek 4.0
* cargo update
Moves to a version of Substrate which uses curve25519-dalek 4.0 (not a rc).
Doesn't yet update the repo to curve25519-dalek 4.0 (as a branch does) due
to the official schnorrkel using a conflicting curve25519-dalek. This would
prevent installation of frost-schnorrkel without a patch.
* use half-aggregation for tm messages
* fmt
* fix pr comments
* cargo update
Achieves three notable updates.
1) Resolves RUSTSEC-2022-0093 by updating libp2p-identity.
2) Removes 3 old rand crates via updating ed25519-dalek (a dependency of
libp2p-identity).
3) Sets serde_derive to 1.0.171 via updating to time 0.3.26 which pins at up to
1.0.171.
The last one is the most important. The former two are niceties.
serde_derive, since 1.0.171, ships a non-reproducible binary blob in what's a
complete compromise of supply chain security. This is done in order to reduce
compile times, yet also for the maintainer of serde (dtolnay) to leverage
serde's position as the 8th most downloaded crate to attempt to force changes
to the Rust build pipeline.
While dtolnay's contributions to Rust are respectable, being behind syn, quote,
and proc-macro2 (the top three crates by downloads), along with thiserror,
anyhow, async-trait, and more (I believe also being part of the Rust project),
they have unfortunately decided to refuse to listen to the community on this
issue (or even engage with counter-commentary). Given their political agenda
they seem to try to be accomplishing with force, I'd go as far as to call their
actions terroristic (as they're using the threat of the binary blob as
justification for cargo to ship 'proper' support for binary blobs).
This is arguably representative of dtolnay's past work on watt. watt was a wasm
interpreter to execute a pre-compiled proc macro. This would save the compile
time of proc macros, yet sandbox it so a full binary did not have to be run.
Unfortunately, watt (while decreasing compile times) fails to be a valid
solution to supply chain security (without massive ecosystem changes). It never
implemented reproducible builds for its wasm blobs, and a malicious wasm blob
could still fundamentally compromise a project. The only solution for an end
user to achieve a secure pipeline would be to locally build the project,
verifying the blob aligns, yet doing so would negate all advantages of the
blob.
dtolnay also seems to be giving up their role as a FOSS maintainer given that
serde no longer works in several environments. While FOSS maintainers are not
required to never implement breaking changes, the version number is still 1.0.
While FOSS maintainers are not required to follow semver, releasing a very
notable breaking change *without a new version number* in an ecosystem which
*does follow semver*, then refusing to acknowledge bugs as bugs with their work
does meet my personal definition of "not actively maintaining their existing
work". Maintenance would be to fix bugs, not introduce and ignore.
For now, serde > 1.0.171 has been banned. In the future, we may host a fork
without the blobs (yet with the patches). It may be necessary to ban all of
dtolnay's maintained crates, if they continue to force their agenda as such,
yet I hope this may be resolved within the next week or so.
Sources:
https://github.com/serde-rs/serde/issues/2538 - Binary blob discussion
This includes several reports of various workflows being broken.
https://github.com/serde-rs/serde/issues/2538#issuecomment-1682519944
dtolnay commenting that security should be resolved via Rust toolchain edits,
not via their own work being secure. This is why I say they're trying to
leverage serde in a political game.
https://github.com/serde-rs/serde/issues/2526 - Usage via git broken
dtolnay explicitly asks the submitting user if they'd be willing to advocate
for changes to Rust rather than actually fix the issue they created. This is
further political arm wrestling.
https://github.com/serde-rs/serde/issues/2530 - Usage via Bazel broken
https://github.com/serde-rs/serde/issues/2575 - Unverifiable binary blob
https://github.com/dtolnay/watt - dtolnay's prior work on precompilation
* add Rs() api to SchnorrAggregate
* Correct serai-processor-tests to dalek 4
* fmt + deny
* Slash malevolent validators (#294)
* add slash tx
* ignore unsigned tx replays
* verify that provided evidence is valid
* fix clippy + fmt
* move application tx handling to another module
* partially handle the tendermint txs
* fix pr comments
* support unsigned app txs
* add slash target to the votes
* enforce provided, unsigned, signed tx ordering within a block
* bug fixes
* add unit test for tendermint txs
* bug fixes
* update tests for tendermint txs
* add tx ordering test
* tidy up tx ordering test
* cargo +nightly fmt
* Misc fixes from rebasing
* Finish resolving clippy
* Remove sha3 from tendermint-machine
* Resolve a DoS in SlashEvidence's read
Also moves Evidence from Vec<Message> to (Message, Option<Message>). That
should meet all requirements while being a bit safer.
* Make lazy_static a dev-depend for tributary
* Various small tweaks
One use of sort was inefficient, sorting unsigned || signed when unsigned was
already properly sorted. Given how the unsigned TXs were given a nonce of 0, an
unstable sort may swap places with an unsigned TX and a signed TX with a nonce
of 0 (leading to a faulty block).
The extra protection added here sorts signed, then concats.
* Fix Tributary tests I broke, start review on tendermint/tx.rs
* Finish reviewing everything outside tests and empty_signature
* Remove empty_signature
empty_signature led to corrupted local state histories. Unfortunately, the API
is only sane with a signature.
We now use the actual signature, which risks creating a signature over a
malicious message if we have ever have an invariant producing malicious
messages. Prior, we only signed the message after the local machine confirmed
it was okay per the local view of consensus.
This is tolerated/preferred over a corrupt state history since production of
such messages is already an invariant. TODOs are added to make handling of this
theoretical invariant further robust.
* Remove async_sequential for tokio::test
There was no competition for resources forcing them to be run sequentially.
* Modify block order test to be statistically significant without multiple runs
* Clean tests
---------
Co-authored-by: Luke Parker <lukeparker5132@gmail.com>
* Add DSTs to Tributary TX sig_hash functions
Prevents conflicts with other systems/other parts of the Tributary.
---------
Co-authored-by: Luke Parker <lukeparker5132@gmail.com>
This will effectively add msrv protections to the entire project as almost
everything grabs from these.
Doesn't add msrv to coins as coins/bitcoin is still frozen.
Doesn't add msrv to services since cargo msrv doesn't play nice with anything
importing the runtime.
This is intended to be a reliable transport between the processors and
coordinator. Since it'll be intranet only, it's written as never fail.
Primarily needs testing and a proper ID.
Provides a DST, and associated metadata as beneficial.
Also utilizes MuSig's context to session-bind. Since set_keys_messages also
binds to set, this is semi-redundant, yet that's appreciated.
