Enterprise wide Git commit signing

Hello Git Users,

My name is Ethan Rahn and I lead Product Security at Arista Networks. I recently completed work on a project which I wanted to highlight for everyone on this list. This is a means for allowing an enterprise to centrally manage code signing keys for all engineers, enforce the signing of all git commits, and audit that the source code repository was not altered after signing. You can read the full blog post here: https://eos.arista.com/commit-signing-with-git-at-enterprise-scale/ . Part of what makes this so exciting to me is that I haven't seen commit signing done at this level before, especially not with having the repo be auditable after the fact. By having the repo be auditable the level of vulnerable infrastructure can be reduced to the code signing keystore; in other words the code repository can be validated at any time to ensure it was not tampered with.

I think that the work done here is very interesting because I have not seen it done elsewhere. Supply chain attacks through source code repositories are a real problem. The solution in most cases seems to be setting up a security perimeter around the repository and checking for unauthorized accesses. If an unauthorized access does occur, or credentials are stolen, it is hard to know the complete set of unauthorized changes made, especially if they are mixed with legitimate work of a number of users over a period of time.

Happy to answer any questions around this or take comments. The work around key management has been open sourced ( references in the blog post ) so that the open source community can benefit from this.

Cheers,

Ethan