Add /etc/profile.d/proxy.sh for upstream proxy to use pkg

[mimugmail]

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Is your feature request related to a problem? Please describe.

In a secure system where internet access in only allowed via proxy I want to fetch updates via pkg. My idea would be to add a proxy.sh with export variables in /etc/profile.d/ folder. Before going deep I'd just like to know if this would be an acceptable approach so a PR also get's in? :)

Describe the solution you like

See above

Describe alternatives you considered

Manual updates

Additional context

Some alternatives: https://forum.opnsense.org/index.php?topic=45005.msg225291#msg225291

[AdSchellevis]

you should only need https://docs.opnsense.org/development/backend/configd.html#extending-the-environment

[ronin3510]

If it is a secure environment it probably is an authenticating proxy, and that's where the lottery begins. Enterprise grade apps / appliances fail or partially fail sending the traffic through the proxy.

Alternatives that come to mind.

a) Seeking a FW exception allowing Source-OPNsense-FWs Dest_OPN_Mirror tcp/443 and a similar rule for http dealing with CRL traffic

b) In case of an authenticating proxy an exception can be made to allow OPN FW(s) to hit the mirror and CRL URLs without authentication

99% of the time I'd push for option a) since you want to be able to upgrade your FWs even when the proxies are down for a reason or other.