smhasher VS rustls

The algorithm passes all SMHasher quality tests and uses rounds of AES block cipher internally, so it is quite robust! For comparison XxH3, t1ha0 and many others don't pass SMHasher (while being slower).

Confirmed, I tested it. https://github.com/rurban/smhasher

There's lots of great hash functions out there: some are super fast, like xxhash and highly optimized, others are also super fast umash and based on interesting math ideas from finite fields^1, while maintaining high quality (according to SMHasher). Others are also fast and interesting (tabulation hash, that may sometimes be seemingly universal), one of the main originators of those ideas are Mikkel Thorup^2. Anyway, a couple of years ago I also tried my hand at building hashes and created a few that passed SMHasher (tifuhash ~ a floating point hash, beamsplitter - a seemingly-universal tabulation style hash, and this one discohash - a "more traditional" ARX-based design (addition rotation xor)^3 ).

0: https://github.com/rurban/smhasher/blob/master/xxh3.h

1: https://pvk.ca/Blog/2022/12/29/fixing-hashing-modulo-alpha-e...

2: https://arxiv.org/abs/1505.01523

3: https://eprint.iacr.org/2018/898.pdf https://crypto.polito.it/content/download/480/2850/file/docu...

4: https://en.wikipedia.org/wiki/BLAKE_(hash_function)

Discohash (posted here) is the fastest one I made, it's simple and doesn't rely on any arch-specific optimizations or vector instructions (AVX etc ~ tho I suppose...they could be added? I'm definitely no expert in them, I barely get away with doing the C/C++ implementations!)

The main mixing round function is:

  mix(const int A) {

ubsan, asan, valgrind tests are missing. some do offer symbolic verification of the algo, but not the implementations.

See my https://github.com/rurban/smhasher#crypto paragraph, and

The spinach story reminds me a lot on the false recommendation of siphash for hash table DDOS prevention. https://github.com/rurban/smhasher#security

The authors came up in their widely cited paper with a proper solution to spread the random hash seed into the inner loop, vastly enhancing its security by avoiding trivial hash collision attacks. But a secure, slow hash function can never prevent from normal hash seed attacks, when the random seed is known somehow. esp. with dynamic languages it's trivial to get the seed externally.

Other trivial countermeasures must be used then, which also don't make hash tables 10x slower, keeping them practical.

This is the best, most comprehensive hash test suite I know of: https://github.com/rurban/smhasher/

you might want to particularly look into murmur, spooky, and metrohash. I'm not exactly sure of what the tradeoffs involved are, or what your need is, but that site should serve as a good starting point at least.

Here is a good comparison table, as you can see, BLAKE can perform in secure way much faster than crc32, so my original point, - to use non weak hashes unless you really have a reason/requirement not to do so

smhasher is a great place to testing results for a massive number of hash algorithms.

The RustTLS project is currently setting up their own CI benchmarking workflow, so I think that you could find some inspiration there: https://github.com/rustls/rustls/issues/1385 and https://github.com/rustls/rustls/issues/1205.

I also studied this question on FFI several weeks ago in terms of "rewrite part of the system in Rust". Unexpected results could be semantic issues (e.g., different error handling methods) or security issues (FFI could be a soundness hole). I suggest going through the issues of libraries that have started rewriting work such as rust-openssl or rustls (This is the one trying to rewrite in whole rust rather than using FFI; however, you will not be able to find the mapping function in the C version and compare them). I hope this helps!

Now for rust implementation of tls. Certificates can be loaded in two ways. * Finds and loads certificates using OS specific tools3 * Uses a rust implementation of webpki4 for loading with certificates5

> Ring is mostly C/Assembly

Crypto needs to be written in Assembly to ensure that operations take a constant time, regardless of input. Writing it in a high level language like C or Rust opens you up to the compiler "optimising" routines and making them no longer constant time.

But you already knew this. And you also knew that the security audit (https://github.com/rustls/rustls/blob/master/audit/TLS-01-re...) of ring was favourable

> No issues were found with regards to the cryptographic engineering of rustls or its underlying ring library. A recommendation is provided in TLS-01-001 to optionally supplement the already solid cryptographic library with another cryptographic provider (EverCrypt) with an added benefit of formally verified cryptographic primitives. Overall, it is very clear that the developers of rustls have an extensive knowledge on how to correctly implement the TLS stack whilst avoiding the common pitfalls that surround the TLS ecosystem. This knowledge has translated reliably into an implementation of exceptional quality.

You said

> a standard library with feature flags and editions would make rust ridiculously much more productive

What's the difference between opting into a library with a feature flag and opting in with a line in Cargo.toml? Let's say you want to use the de-facto regex library. Would it really be ridiculously productive if you said you wanted the "regex" feature flag instead of the "regex" crate?

I do agree that the standard library does need a versioning story so they can remove long deprecated functions. Where it gets complicated is if a new method is reintroduced using the same name in a later edition.

I used the commands listed in the .sh file here: https://github.com/rustls/rustls/tree/main/test-ca to generate keys/certs for a server and a client (with IP.1 records for SANs). I have added the local root CA to the trust store of each VM.

This is great news, this was our single biggest annoyance with rustls. One of our cloud providers choses to issue their hosted postgres instances with TLS certificates with IP addresses. Unusual, but valid per the spec, so why not. Apparently a practise that's also popular in kubernetes settings, so I'm somewhat surprised it took 5 years to close the issue, but now I can finally recommend people to use rustls without mentioning any gotchas.

I believe it is more relevant than you think: servers running in containers, web assembler tasks running in browsers, embedded devices and kernels with total control of the system, all have the ability to do something more sensible than plain out SIGABRT or similar, and in many the case is not that the complete system is falling down. For example RustTLS is looking into allowing fallible allocators and as a pretty general-purpose library that seems like a nice feature. I do wish ulimit -v worked in a sensible manner with applications.