no-network build policy rules

[Jan Palus]

On 26.10.2025 16:16, Jakub Bogusz wrote:
> I found that there are different meanings of "no network usage":
> 1) builders cannot use external resources/hosts, which is enforced by
>   non-functional resolv.conf
> 2) but `unshare --net` introduced recently in builder script does even
>   more: it disables the use of localhost connections (binding/connecting
>   to lo interface/127.0.0.1/8 addresses)
> 
> Many more test suites rely on loopback connections working than using
> external resources, so there are many (esp. python or perl modules,
> openssl, openssh, git etc.) packages which can be built fine on builders,
> but not with builder script (without --bnet).
> 
> How should be packages (and their default tests options) prepared, to
> compy with 1) or 2)?

My attempt at adding ip address to loopback interface landed on
`netns-with-lo-addr` branch. I'm not particularly proud of it but it
seems to work. I would appreciate second look and comments.