Cardano Updates

JWT.verify did not validate the nbf (not before) claim, so JWTs with nbf in the future were incorrectly considered valid. This is a security issue per RFC 7519 Section 4.1.5.

Added an explicit nbf check after JWT decode: if nbf is present and the current time is before it, verify() returns false. JWTs without an nbf claim keep the previous behavior (no nbf enforced).

This is a sister fix to #489/#550 (which addressed the exp claim).

Closes #551

Signed-off-by: Seydi Charyyev <[email protected]>

Signed-off-by: Seydi Charyyev <[email protected]>

This commit implements a compact bitmaps via ByteStrings, adapted from
the Leios voting committee demo package (leios-wfa-ls-demo):

https://github.com/cardano-scaling/leios-wfa-ls-demo/blob/main/leios-wfa-ls-demo/lib/Cardano/Leios/BitMapPV.hs

Co-authored-by: Agustin Mista <[email protected]>
Co-authored-by: Thomas BAGREL <[email protected]>
Co-authored-by: Nicolas BACQUEY <[email protected]>

This commit implements conversion routines between the brand-new
(concrete) Peras votes and certificates and their corresponding
(abstract) voting committee counterparts.

This is done by introducing a `VotingCommitteeSupportsPeras` type class
to allow us to easily change the underlying voting committee
implementation via a proxy type.

Co-authored-by: Agustin Mista <[email protected]>
Co-authored-by: Thomas BAGREL <[email protected]>
Co-authored-by: Nicolas BACQUEY <[email protected]>

This commit defines a concrete PerasCrypto scheme using BLS signatures
to instantiate all the voting committee superclasses needed by the WFALS
and EveryoneVotes voting committee implementations.

Note that these instances are heavily inspired by the ones defined for
TestCrypto in the generic voting committee test-suite, albeit with
slightly different types and more documentation.

Co-authored-by: Agustin Mista <[email protected]>
Co-authored-by: Thomas BAGREL <[email protected]>
Co-authored-by: Nicolas BACQUEY <[email protected]>

This commit adds conversion rountrip tests between concrete Peras votes
and certificates and their corresponding (abstract) counterparts in the
WFALS and EveryoneVotes voting committee implementations.

Notably, the roundtrip properties allow testing both total (WFALS) and partial
(EveryoneVotes) conversions, generating both good and bad cases and
contrasting them against their expected rountrip outcome.

Co-authored-by: Agustin Mista <[email protected]>
Co-authored-by: Thomas BAGREL <[email protected]>
Co-authored-by: Nicolas BACQUEY <[email protected]>

This commit adds test helpers to aid with the definition of the upcoming
roundtrip properties for concrete Peras votes and certificates.

Co-authored-by: Agustin Mista <[email protected]>
Co-authored-by: Thomas BAGREL <[email protected]>
Co-authored-by: Nicolas BACQUEY <[email protected]>

Co-authored-by: Agustin Mista <[email protected]>
Co-authored-by: Thomas BAGREL <[email protected]>
Co-authored-by: Nicolas BACQUEY <[email protected]>

This commit defines concrete data structures for Peras votes and certificates
using BLS signatures to represent vote/cert signatures as well as
non-persistent eligibility proofs.

In addition it defines serialization routines for both types, using a
compact bitmap representation in the case of certificates.

Co-authored-by: Agustin Mista <[email protected]>
Co-authored-by: Thomas BAGREL <[email protected]>
Co-authored-by: Nicolas BACQUEY <[email protected]>

This commit defines some common test helpers used by the upcoming
property and conformance tests for both WFALS and EveryoneVotes.

Co-authored-by: Nicolas BACQUEY <[email protected]>
Co-authored-by: Thomas BAGREL <[email protected]>
Co-authored-by: Agustin Mista <[email protected]>

Co-authored-by: Nicolas BACQUEY <[email protected]>
Co-authored-by: Thomas BAGREL <[email protected]>
Co-authored-by: Agustin Mista <[email protected]>

In addition to enforcing that all votes used to forge a certificate have
the same target (election ID and candidate), we should also
conservatively also check for duplicates to avoid any bug that would
silently allow for potentially equivocating votes to slip into a
certificate.

This commit tweaks the definition of VotesWithSameTarget (the data
structure expected by forgeCert) to addionally check for duplicates when
constructing it. This is done by asking for an additional ordering
predicate between votes, where equality signals duplicated (i.e.
potentially equivocating) votes.

In addition, we now provide an additional (unsafe) smart constructor
that runs this test via compiler-enabled assertion. Which can be used in
the case that the client code can guarantee the desired invariants by
construction.

Finally, it relaxes the smart constructor interface a bit to allow for
easier testing.

Co-authored-by: Nicolas BACQUEY <[email protected]>
Co-authored-by: Thomas BAGREL <[email protected]>
Co-authored-by: Agustin Mista <[email protected]>

This commit implements the deterministic core of the weighted
Fait-Accompli algorithm using a precomputed extended stake distribution,
shareable across multiple voting committees running on the same epoch.

The implementation includes a tiebreaker mechanism to allow altering the
order of pools with the same stake when the threshold index between
persistent and non-persistent voters would land between them. This can
later be instantiated to allow for a fair split across epochs.

Co-authored-by: Nicolas BACQUEY <[email protected]>
Co-authored-by: Thomas BAGREL <[email protected]>
Co-authored-by: Agustin Mista <[email protected]>

This commit implements the local sortition fallback scheme needed by
wFA^LS to allocate non-persistent voters. Each non-persistent voter
provides a VRF output that gets normalized and compared against the
output of a numerically-stable stake-weighted Poisson distribution.

Co-authored-by: Nicolas BACQUEY <[email protected]>
Co-authored-by: Thomas BAGREL <[email protected]>
Co-authored-by: Agustin Mista <[email protected]>