Commit Graph

13 Commits

Author SHA1 Message Date
Luke Parker
a59bbe7635 Impl is_odd for dfg::Scalar 2022-08-31 01:05:30 -04:00
Luke Parker
cc0c6fb5ac Apply the optimized pow to dalek-ff-group
Saves ~40% from Monero hash_to_curve, assisting with #68.
2022-08-31 00:57:23 -04:00
Luke Parker
081b9a1975 FROST Ed448 (#107)
* Theoretical ed448 impl

* Fixes

* Basic tests

* More efficient scalarmul

Precomputes a table to minimize additions required.

* Add a torsion test

* Split into a constant and variable time backend

The variable time one is still far too slow, at 53s for the tests (~5s a 
scalarmul). It should be usable as a PoC though.

* Rename unsafe Ed448

It's not only unworthy of the Serai branding and deserves more clarity
in the name.

* Add wide reduction to ed448

* Add Zeroize to Ed448

* Rename Ed448 group.rs to point.rs

* Minor lint to FROST

* Ed448 ciphersuite with 8032 test vector

* Macro out the backend fields

* Slight efficiency improvement to point decompression

* Disable the multiexp test in FROST for Ed448

* fmt + clippy ed448

* Fix an infinite loop in the constant time ed448 backend

* Add b"chal" to the 8032 context string for Ed448

Successfully tests against proposed vectors for the FROST IETF draft.

* Fix fmt and clippy

* Use a tabled pow algorithm in ed448's const backend

* Slight tweaks to variable time backend

Stop from_repr(MODULUS) from passing.

* Use extended points

Almost two orders of magnitude faster.

* Efficient ed448 doubling

* Remove the variable time backend

With the recent performance improvements, the constant time backend is 
now 4x faster than the variable time backend was. While the variable 
time backend remains much faster, and the constant time backend is still 
slow compared to other libraries, it's sufficiently performant now.

The FROST test, which runs a series of multiexps over the curve, does 
take 218.26s while Ristretto takes 1 and secp256k1 takes 4.57s.

While 50x slower than secp256k1 is horrible, it's ~1.5 orders of 
magntiude, which is close enough to the desire stated in 
https://github.com/serai-dex/serai/issues/108 to meet it.

Largely makes this library safe to use.

* Correct constants in ed448

* Rename unsafe-ed448 to minimal-ed448

Enables all FROST tests against it.

* No longer require the hazmat feature to use ed448

* Remove extraneous as_refs
2022-08-29 02:32:59 -05:00
Luke Parker
c53e7ad6c7 Bump dalek-ff-group version 2022-08-18 17:11:55 -04:00
J. Burfeind
a2aa182cc4 Conditional negate (#90)
* Reorder tests in dalek-ff-group

* Add required method for ConditionallyNegatable

Adds lifetime bound implementation `Neg`
for borrowed FieldElements in dalek-ff-group.
2022-08-18 15:02:31 -05:00
aiyion.prime
45912d6837 Add implementation for sqrt_ratio_i()
in dalek-ff-group
2022-08-18 13:38:57 -05:00
Luke Parker
a73bcc908f Add missing test annotation 2022-08-13 19:43:43 -04:00
J. Burfeind
a58b3a133c Add implementation for is_odd() (#79)
in dalek-ff-group

Co-authored-by: Luke Parker <lukeparker5132@gmail.com>
2022-08-12 15:05:48 -05:00
J. Burfeind
169d5e26ca Add constant EDWARDS_D in dalek-ff-group (#78) 2022-08-12 15:00:55 -05:00
Luke Parker
797be71eb3 Utilize zeroize (#76)
* Apply Zeroize to nonces used in Bulletproofs

Also makes bit decomposition constant time for a given amount of 
outputs.

* Fix nonce reuse for single-signer CLSAG

* Attach Zeroize to most structures in Monero, and ZOnDrop to anything with private data

* Zeroize private keys and nonces

* Merge prepare_outputs and prepare_transactions

* Ensure CLSAG is constant time

* Pass by borrow where needed, bug fixes

The past few commitments have been one in-progress chunk which I've 
broken up as best read.

* Add Zeroize to FROST structs

Still needs to zeroize internally, yet next step. Not quite as 
aggressive as Monero, partially due to the limitations of HashMaps, 
partially due to less concern about metadata, yet does still delete a 
few smaller items of metadata (group key, context string...).

* Remove Zeroize from most Monero multisig structs

These structs largely didn't have private data, just fields with private 
data, yet those fields implemented ZeroizeOnDrop making them already 
covered. While there is still traces of the transaction left in RAM, 
fully purging that was never the intent.

* Use Zeroize within dleq

bitvec doesn't offer Zeroize, so a manual zeroing has been implemented.

* Use Zeroize for random_nonce

It isn't perfect, due to the inability to zeroize the digest, and due to 
kp256 requiring a few transformations. It does the best it can though.

Does move the per-curve random_nonce to a provided one, which is allowed 
as of https://github.com/cfrg/draft-irtf-cfrg-frost/pull/231.

* Use Zeroize on FROST keygen/signing

* Zeroize constant time multiexp.

* Correct when FROST keygen zeroizes

* Move the FROST keys Arc into FrostKeys

Reduces amount of instances in memory.

* Manually implement Debug for FrostCore to not leak the secret share

* Misc bug fixes

* clippy + multiexp test bug fixes

* Correct FROST key gen share summation

It leaked our own share for ourself.

* Fix cross-group DLEq tests
2022-08-03 03:25:18 -05:00
Luke Parker
e67033a207 Apply an initial set of rustfmt rules 2022-07-16 15:16:30 -05:00
Luke Parker
cf28967754 Consolidate macros in dalek-ff-group 2022-07-10 16:48:08 -04:00
Luke Parker
6ce506a79d Add an implementation of Ed25519 FieldElements 2022-07-10 15:20:42 -04:00