23 pointsby LoadingALIAS7 hours ago3 comments
  • dave_universetf5 hours ago
    The readme has strong LLM smells. Was the code written by an LLM as well?

    What is your experience with cryptographic engineering, in particular avoiding common implementation pitfalls that bite first-time implementers of cryptographic primitives?

    Are the primitives tested against Wycheproof vectors, and proofed against the common implementation mistakes they document?

    • LoadingALIASan hour ago
      Yeah, all fair questions.

      To address the LLM question - almost all MD files in the codebase were built around the codebase by an LLM. I simply don't have the time; this project is a side project and not my main squeeze. This is also a pre-v1 codebase; I will have time soon enough to address anything overly 'LLM' flavored.

      My experience covers nearly two decades in one way or another. Having said that, I've never felt like I had the time, nor the need, for rscrypto. The last year was different; I genuinely needed this myself for my actual work. I have worked on rscrypto in part for a year. This isn't like a whimsical LLM codebase or some vibe coded junk.

      I use LLMs in my workflows every single day and have for the better part of two-years; I gain more trust in them almost weekly, too. I feel like there isn't an engineer on Earth who can say otherwise and if there is... I'd probably argue with them against integrating LLMs into their tooling in some way.

      Finally, the actual important question... not all primitives are tested against Wycheproof vectors yet. RSA - yes; the whole crate, not yet. Again, it's just a time thing. I've used official RFC/NIST vectors, RustCrypto/oracle differential tests, proptests, fuzz corpus replay, Miri where applicable, and backend-vs-portable equivalence tests to cover the rest of the codebase.

      Also, “proofed” is too strong a word for test vectors, IMO. Wycheproof is regression evidence against known bug classes, not a proof of cryptographic correctness.

      Nevertheless, it's a valid point and it's covered in my backlog as of like a month ago.

    • tux34 hours ago
      Yeah, spot on. This is what the code looks like: https://github.com/loadingalias/rscrypto/blob/4e24772a54fef3...

      Look at these section comments that LLMs love ("// ─── Rotation helpers ────")

      Now you sometimes see these section comments in legacy codebases that have very long files. What you don't see people use is U+2500 BOX DRAWINGS LIGHT HORIZONTAL unicode characters padded out just right to look pretty. We humans have regular keyboards, but these AIs are trained to output emojis and pretty unicode.

      • LoadingALIASan hour ago
        The documentation and to a large extent commenting, auditing, and almost every markdown file was likely generated with an LLM. Do not mistake that for competence or quality.

        This is a pre-v1 codebase. I'm looking for bench-methodology failures; I'm looking for API issues and/or code smells. I'm looking for ASM/SIMD weak points and/or testing issues.

        Over time, as I have the capacity, I will almost certainly clean up anything that's just not necessary. Having said that, if something feels clean and it was done by an LLM in my harness/workflow - I'm 100% happy to leave it.

        Please, dig into the code. Let me know what you see. Thanks.

  • sevenoftwelve5 hours ago
    Hi @LoadingAlias,

    > Constant-time MAC, AEAD, and signature verification.

    That sounds suspiciously incomplete to me.

    Which cryptographic algorithms in the library are currently not implemented in constant time?

    Where did the speedup come from? How where these optimizations achieved?

    What motivated you to write the library? Why not contribute to existing rust crypto libraries instead? How is the work financed?

    What peer review strategy are you following with the library? Who else but yourself has verified this code?

    • LoadingALIASan hour ago
      Hey! Thank you for taking a second. Really, I appreciate it. So... fair criticism. The constant-time line is too compressed and should probably be replaced w/ some kind of matrix.

      I ask you to give me a few hours. I'm not able to like devote the time to the comments that it deserves. I'm nearly home, give me a bit, please.

      Thanks!

    • CodesInChaos5 hours ago
      "Constant-time signature verification" stands out, since unlike signature creation, verification doesn't involve secrets, and thus doesn't require constant-time in most threat models.
    • sevenoftwelve5 hours ago
      Why do the different sha2 variants not share code? This seems like a lot of opportunities for small mistakes/discrepancies; especially considering the many architectures.

      Was any of this generated using AI?

  • LoadingALIAS6 hours ago
    I've built rscrypto because crypto kept being where my Rust database stopped being portable: different stack on the server, different target story on WASM, different answer on RISC-V/POWER/IBM Z, and a different audit surface every time I added a primitive. The supply chain risk, given the landscape we're in today, was too high.

    v0.3.1 is one feature-selected crate. Leaf features when you need one primitive (`sha2`, `rsa`, `aes-gcm`, `ed25519`, etc.) or `full` for the stack. Scope includes SHA-2/3, SHAKE, cSHAKE256, BLAKE2, BLAKE3, Ascon hash/XOF, XXH3, RapidHash, CRCs, HMAC, KMAC256, HKDF, PBKDF2, Argon2, scrypt, PHC strings, RSA, Ed25519, X25519, AES-128/256-GCM, AES-128/256-GCM-SIV, ChaCha20-Poly1305, XChaCha20-Poly1305, AEGIS-256, and Ascon-AEAD128.

    The primitive stack has zero default deps and no C-libs or FFI. Optional `getrandom`, `serde`, and `rayon` features stay out until enabled.

    The current bench evidence is across nine Linux runners (Intel Sapphire Rapids, Intel Ice Lake, AMD Zen4, AMD Zen5, Graviton3, Graviton4, IBM Z/s390x, IBM POWER10/ppc64le, RISE RISC-V) and my local Apple MBP M1.

    Linux vs. fastest-external: 3,545 wins and 5,210 wins-or-ties out of 5,832 comparisons, 1.61x geomean.

    MBP M1 vs fastest-external: 235 wins and 450 wins-or-ties out of 463 comparisons, 1.25x geomean.

    BLAKE3 large inputs (`>=64 KiB`) are 2.31x geomean improvement across Linux vs the official `blake3` crate and 1.80x on MBP M1.

    While it's not universally faster - it's incredibly close. Current weak spots include PBKDF2-SHA256 setup at `iters=1`, X25519 DH, RSA verification on Arm/RISC-V, small-message AEAD rows, MBP M1 BLAKE3 64 KiB rows, HMAC-SHA256 bulk pressure against `aws-lc-rs`, and SHA3-256 streaming on Apple Silicon. The `./benchmark_results/OVERVIEW.md` lists the losses next to the wins in more detail.

    Trust, Testing, Etc: portable Rust is the byte-for-byte authority. SIMD/ASM paths are accelerators and are differential tested against the portable path. MAC, AEAD, and signature comparisons are constant-time. Secret-bearing types zeroize on drop. I've got a pretty thorough Miri and Fuzzer testing gate setup, too. The RSA impl has it's own CI gate. Codecov = 73.06, fuzzing included.

    This is not FIPS 140-3 validated, not a TLS stack, not a key store, and not third-party audited yet. I am genuinely interested in a third-party audit and would LOVE to plan for FIPS 140-3 validation, but it's just out of my reach right now.

    The codebase/lib is obviously pre-v1 and I'm asking for public review while API changes are still relatively cheap.

    Repo: https://github.com/loadingalias/rscrypto

    Crate: https://crates.io/crates/rscrypto

    Benches: https://github.com/loadingalias/rscrypto/blob/main/benchmark...

    Migration Guides: https://github.com/loadingalias/rscrypto/blob/main/docs/migr...

    Me: https://x.com/loadingalias

    If you're testing, benching, etc. and happen to stumble across inconsistencies, vulnerabilities, etc. - please just reach out directly via 'X' or use Github's Vulnerability Reporting. There are a decent number of people already using the library.

    Also, the 'fastest-external' competitors for perf comparisons are almost always one of the following: aws-lc-rs, ring, RustCrypto, dryoc, OpenSSL, Blake3 and/or one of the many 'crc-fast/fast-crc' crate variations. I benched these external crates against eachother in the beginning to trace the most performant before hunting inefficiency and cutting out any external deps/c-libs. So, if the benches show a 2x geomean over Blake3... that means it's over the fastest implementation of Blake3 I could find and bench publicly.