> Focusing on the HTTPS ecosystem, including components such as the TLS protocol and its underlying cryptographic algorithms, Project Everest began in 2016 aiming to build and deploy formally verified implementations of several of these components in the F* proof assistant.
> […] Code from HACL*, ValeCrypt and EverCrypt is deployed in several production systems, including Mozilla Firefox, Azure Confidential Consortium Framework, the Wireguard VPN, the upcoming Zinc crypto library for the Linux kernel, the MirageOS unikernel, the ElectionGuard electronic voting SDK, and in the Tezos and Concordium blockchains.
A formally verified stack for Certificate Transparency would be a good way to secure key distribution (and revocation); where we currently depend upon a TLS library (typically OpenSSL), GPG + HKP (HTTP Key Protocol).
Fuzzing on an actual hardware - with stochastic things that persist bits between points in spacetime - is a different thing.
Funny, the first hit for that search you linked is... my comment above. The "few things" other than that are for alternatives to PKIX, which is fine and good, but PKIX will be with us for a long time yet. As for Everest, it jives with what I wrote above, that verified implementations of TLS are feasible (Everest also implements QUIC and similar), but -surprise!- not listed is PKIX.
I know, it sounds crazy, really crazy, but PKIX is much bigger than TLS. It's big. It's just big.
The crypto, you can verify. The session and presentation layers, you can verify. Heck, maybe you can verify your app. PKIX implementations of course can be verified in principle, but in fact it would require a serious amount of resources -- it would be really expensive. I hope someone does it, to be sure.
I suppose the first step would be to come up with a small profile of PKIX that's just enough for the WebPKI. Though don't be fooled, that's not really enough because people do use "mTLS" and they do use PKINIT, and they do use IPsec (mostly just for remote access) with user certificates, and DoD has special needs and they're not the only ones. But a small profile would be a start -- a formal specification for that is within the realm of the achievable in reasonably short order, though still, it's not small.
Both a gap and an opportunity; someone like an agency or a FAANG with a budget for something like this might do well to - invest in the formal methods talent pipeline and - very technically interface with e.g. Everest about PKIX as a core component in need of formal methods.
> Our first ingredient is "frankencerts," synthetic certificates that are randomly mutated from parts of real certificates and thus include unusual combinations of extensions and constraints. Our second ingredient is differential testing: if one SSL/TLS implementation accepts a certificate while another rejects the same certificate, we use the discrepancy as an oracle for finding flaws in individual implementations.
> Differential testing with frankencerts uncovered 208 discrepancies between popular SSL/TLS implementations such as OpenSSL, NSS, CyaSSL, GnuTLS, PolarSSL, MatrixSSL, etc.
> Focusing on the HTTPS ecosystem, including components such as the TLS protocol and its underlying cryptographic algorithms, Project Everest began in 2016 aiming to build and deploy formally verified implementations of several of these components in the F* proof assistant.
> […] Code from HACL*, ValeCrypt and EverCrypt is deployed in several production systems, including Mozilla Firefox, Azure Confidential Consortium Framework, the Wireguard VPN, the upcoming Zinc crypto library for the Linux kernel, the MirageOS unikernel, the ElectionGuard electronic voting SDK, and in the Tezos and Concordium blockchains.
S2n is Amazon's formally verified TLS library. https://en.wikipedia.org/wiki/S2n
IDK about a formally proven PKIX. https://www.google.com/search?q=formally+verified+pkix lists a few things.
A formally verified stack for Certificate Transparency would be a good way to secure key distribution (and revocation); where we currently depend upon a TLS library (typically OpenSSL), GPG + HKP (HTTP Key Protocol).
Fuzzing on an actual hardware - with stochastic things that persist bits between points in spacetime - is a different thing.