Instrumenting Rust TLS with eBPF
Coroot is an open source observability tool that uses eBPF to collect telemetry directly from applications and infrastructure. One of the things it does is capture L7 traffic from TLS connections without any code changes, by hooking into TLS libraries and syscalls. Works great for OpenSSL. Works for Go. Then rustls enters the picture and everything stops being obvious. With OpenSSL, everything is nicely wrapped: From eBPF’s point of view this is perfect: Everything happens inside one call.