[walrus01]

To be fair, advanced real world knowledge of public/private key PKIs (x.509 or other), things like root CAs, are a fairly esoteric and very specialized field of study. There's people whose regular day jobs are nothing but doing stuff with PKI infrastructure and their depth of knowledge on many other non-PKI subjects is probably surface level only.

[hannob]

I know quite a bit about PKI and X.509, and I can tell you that much: the overlap with how DNSSEC works is limited.

[silisili]

As is the overlap between DNSSEC and DNS itself, to be honest.

I once worked at the level of administering DNSSEC for 300+ TLDs. It's its own world. When that company was winding down, I tried to continue in the field but the most common response (outside of no response, of course), was 'we already have a DNS team/vendor/guy.' And well, then things like this happen. I won't throw stones though, it's a lot to learn and can be incredibly brittle.

[mschuster91]

It's not made easier by the fact that a lot of cryptography is either very old and arcane or it's one hell of a mess of code that doesn't make sense without reading standards.

I had the misfortune of having to dig deep into constructing ASN.1 payloads by hand [1] because that's the only thing Java speaks, and oh holy hell is this A MESS because OF COURSE there's two ways to encode a bunch of bytes (BIT STRING vs OCTET STRING) and encoding ed25519 keys uses BOTH [2].

And ed25519 is a mess in itself. The more-or-less standard implementation by orlp [3] is almost completely lacking any comments explaining what is going on where and reading the relevant RFCs alone doesn't help, it's probably only understandable by reading a 500 pages math paper.

It's almost as if cryptographers have zero interest in interested random people to join the field.

End of rant.

[1] https://github.com/msmuenchen/meshcore-packets-java/blob/mai...

[2] https://datatracker.ietf.org/doc/html/rfc8410#appendix-A

[3] https://github.com/orlp/ed25519/tree/master

[Muromec]

The trick to asn.1 is to generate both parser and serializer from the spec. Elliptic curve math on the other hand is ... yeah, you need to know the math and also know the tricks to code that implements it. Both of those have steep learning curve, but it's hardly because it's a mess or it's old.

[thayne]

The problem with ASN.1 is that it is big and complicated, and you only need a fraction of it for cryptography, and it isn't really used for anything outside of pki anymore.

It wouldn't be as bad if asn.1 had cought on more as a general purpose serialization format and there were ubiquitous decent libraries for dealing with it. But that didn't happen. Probably partly because there are so many different representations of asn.1.

A bespoke serialization specifically for certificates might actually have aged better, if it was well designed.

[jll29]

Assuming there are some libraries for it, would this make a pretty good case for LLM-generated ports of these existing libraries into other languages or onto other OSs/platforms? One implementation could be treated as "the spect".

[pocksuppet]

ASN.1 is protobufs designed by committee. It is a general-purpose serialization format, but there's no good reason to choose it instead of protobufs.

[thayne]

> It is a general-purpose serialization format

Yes. My point is that in practice it hasn't really been used for much outside of cryptography.

> there's no good reason to choose it instead of protobufs

Well, the reason it is used in a lot of the places it is, is because protobufs didn't exist when those protocols or file formats were created.

There are also some things that ASN.1 does better at a technical level. Of important significance to cryptography is that the DER representation is "canonical", meaning that there is only one way to serialize a set of data to bytes. That's important because it means that you can just hash the contents of the serialization for signatures, rather than having to have some kind of separate canonicalization step (which is a common source of mistakes).

[mschuster91]

> Both of those have steep learning curve, but it's hardly because it's a mess or it's old.

Bitpacking structures used to be important in the 60s. That time has passed, unless you're dealing with LoRa, NFC or other cases of highly constrained bandwidth there are way better options to serialize and deserialize information. It's time to move on, and the complexity of all the legacy garbage in crypto has been the case of many a security vulnerability in the past.

As for the code, it might be personal preference but I'd love to have at least some comments referring back to a specification or original research paper in the code.

[Muromec]

I think you misunderstand the problem asn.1 solves and constrains it works within (both 30 years ago and now). We sure can have a better one now once we learned all the lessons and know what good parts to keep, but this critique of bitpacking is misplaced.

[Avamander]

ASN.1 is not used because of just bitpacking. There are other benefits to ASN.1 and it's probably one of the least problematic parts there.

People who have thought they can do better have made things like PGP. It's one of the worst cryptographic solutions out there. You're free to try as well though.

[Muromec]

People who though they can do better did JWT, that is not complicated at all and has no bugs as well. Also solves 20% of what asn.1 is used for.

[thayne]

Maybe a bit pedantic, but it would actually be the more general JOSE which includes tokens (JWT), signatures (JWS), and key transmission (JWK).

And there is a related binary format that uses CBOR (COSE) as well.

[tptacek]

The trick to ASN.1 is to serialize/unserialize it backwards.

[dwattttt]

#1 NSA, I get it now!

[cyberax]

X.509 is a deep legacy, but at least at this point it's well tested.

> because that's the only thing Java speaks

No, it most definitely is not. You can just construct a private key directly in BouncyCastle: https://downloads.bouncycastle.org/java/docs/bcprov-jdk18on-...

I'm 100% certain that you also can do that with raw java.security. I did that about 15 years ago with raw RSA/EC keys. You can just directly specify the private exponent for RSA (as a bigint!) or the curve point for EC.

Ditto for ed25519, you can just take the canonical implementation from DJB. And you really really shouldn't do that anyway, please just use OpenSSL or another similar major crypto library.

[mschuster91]

> I'm 100% certain that you also can do that with raw java.security.

I tried that, the problem is Meshcore specific - they do their own weird shit with private and public keys [1]. Haven't figured out how to do the private key import either, because in the C source code (or in python re-implementations) Meshcore just calls directly into the raw ed25519 library to do their custom math... it's a mess.

[1] https://jacksbrain.com/2026/01/a-hitchhiker-s-guide-to-meshc...

[cyberax]

I'm playing with LORA/Meshcore right now (I have an nRF52840 lying around). I'm pretty sure I know how to do that, will take a look.

[Muromec]

I wouldn't recommend touching openssl (the library, command line tools are okay-ish) with anything that breaths life.

[tptacek]

The typical vector for entering cryptography as a professional is called "grad school".

[hathawsh]

Is that actually true, though? Even though it's not really my job, I find myself debugging certificates and keys at least once a month, and that's after automating as much as possible with certbot and cloud certificates. PKI always seems to demand attention.

[walrus01]

In my initial comment, I meant more in terms of complexity and planning from the perspective of the people who are running the public/private key infrastructure on the other side/upstream of what you're doing as a letsencrypt end user.

Broadly similar general concept to the team responsible for the DNSSSEC signing keys for an entire ccTLD.

Yeah a x509 PKI / root CA is a very different thing than DNSSSEC but they have a number of general logical similarities in that the chain of trust ultimately comes down to a "do not fuck this up" single point of failure.