Future-proofing SaltStack

At Cloudflare, we are preparing the Internet and our infrastructure for the arrival of quantum computers. A sufficiently large and stable quantum computer will easily break commonly deployed cryptography such as RSA. Luckily there is a solution: we can swap out the vulnerable algorithms with so-called post-quantum algorithms that are believed to be secure even against quantum computers. For a particular system, this means that we first need to figure out which cryptography is used, for what purpose, and under which (performance) constraints. Most systems use the TLS protocol in a standard way, and there a post-quantum upgrade is routine. However, some systems such as SaltStack, the focus of this blog post, are more interesting. This blog post chronicles our path of making SaltStack quantum-secure, so welcome to this adventure: this secret extra post-quantum blog post!

SaltStack, or simply Salt, is an open-source infrastructure management tool used by many organizations. At Cloudflare, we rely on Salt for provisioning and automation, and it has allowed us to grow our infrastructure quickly.

Salt uses a bespoke cryptographic protocol to secure its communication. Thus, the first step to a post-quantum Salt was to examine what the protocol was actually doing. In Continue reading