Httptap: View HTTP/HTTPS requests made by any Linux program

I'm more interested in the HTTPS part. I see that it sets some common environment variables [1] to instruct the program to use the CA bundle in the temporary directory. This seems to pose a similar issue like all the variants of `http_proxy`: the program may simply choose to ignore the variable.

I see it also mounts an overlay fs for `/etc/resolv.conf` [2]. Does it help if httptap mounts `/etc/ca-certificates` directory with the temporary CA bundle?

[1] https://github.com/monasticacademy/httptap/blob/cb92ee3acfb2...

[2] https://github.com/monasticacademy/httptap/blob/cb92ee3acfb2...

It's true that httptap mounts an overlay on /etc/resolv.conf. This is, as you'd expect, due to the also-sort-of-frustrating situation with respect to DNS resolution in which, like CA roots, there isn't a truly reliable way to tell an arbitrary process what DNS server to use, but /etc/resolv.conf is a pretty good bet. As soon as you put a process into a network namespace you have to provide it with DNS resolution because it can no longer access localhost:53, which is the systemd resolver, which is the most common setup now on desktop linux systems.

I do think it might help to mount /etc/ca-certificates as an overlay. When I started looking into the structure of that directory I was kind of dismayed... it's incredibly inconsistent from one distro to the next. Still, it's doable. Interested in any knowledge you might be able to share about how to add a cert to that directory in a way that would be picked up by at least some TLS implementations.