New mlkem lib

[Nichokas]

This pull request introduces significant updates to the cryptographic implementation, replacing the Kyber library with libcrux_ml_kem and updating the random number generation approach to use rand_chacha, safer than using rand::threaded_rng. It also includes various refactors, test updates, and a new script for generating test vectors.

[Copilot]

Pull Request Overview

This PR migrates the cryptographic implementation from kyberlib to libcrux_ml_kem, updates the random number generation to use rand_chacha, and refactors various areas including tests, benchmarks, and documentation to reflect the new APIs.

• Migration to libcrux_ml_kem with updated keypair, encapsulation, and decapsulation functions
• Update of randomness generation using ChaCha20Rng from OS sources for reproducibility
• Refactoring of API interfaces, test vector generation, and documentation improvements

Reviewed Changes

Copilot reviewed 10 out of 10 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
src/tests.rs	Updated tests to use new public key getters and revised keypair construction
src/main.rs	Added a new test vector generation script
src/lib.rs	Refactored encryption/decryption functions to use fixed-size arrays and new ML-KEM API
src/key_exchange.rs	Revised key exchange to adopt libcrux_ml_kem and update key derivation logic
src/encryption.rs	Minor documentation and example adjustments in encrypt/decrypt helper functions
benches/kyber_bench.rs	Updated benchmarking tests to reflect use of the new ML-KEM key and encapsulation APIs
benches/chacha_bench.rs	Modified random number generation in benchmarks to use ChaChaOsRng for consistency
Cargo.toml	Removed obsolete dependencies and added libcrux-ml-kem and updated rand_chacha versions

Comments suppressed due to low confidence (1)

src/lib.rs:154

• The call to mlkem768::decapsulate contains an extraneous trailing comma, which could lead to a syntax error. Please remove the trailing comma.

let shared_secret = mlkem768::decapsulate(server_kp.private_key(), &kyber_ciphertext_array, );

[codspeed-hq]

CodSpeed Performance Report

Merging #56 will improve performances by 83.55%

_{Comparing new-mlkem-lib (83a3015) with master (e168be6)}

Summary

⚡ 6 improvements
✅ 9 untouched benchmarks
🆕 3 new benchmarks
⁉️ 3 dropped benchmarks

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
⁉️	kyber_decapsulation	228.6 µs	N/A	N/A
🆕	mlkem_decapsulation	N/A	124.9 µs	N/A
⁉️	kyber_encapsulation	234.3 µs	N/A	N/A
🆕	mlkem_encapsulation	N/A	117.6 µs	N/A
⚡	full_decryption_long	278.9 µs	200.4 µs	+39.19%
⚡	full_decryption_medium	265.9 µs	167.1 µs	+59.16%
⚡	full_decryption_short	261 µs	152.5 µs	+71.12%
⚡	full_encryption_long	281.7 µs	179.9 µs	+56.62%
⚡	full_encryption_medium	271.6 µs	155.2 µs	+74.99%
⚡	full_encryption_short	266.5 µs	145.2 µs	+83.55%
⁉️	kyber_keypair_generation	200.4 µs	N/A	N/A
🆕	mlkem_keypair_generation	N/A	125.3 µs	N/A