Feature/new client file configuration section with custom dns config

[nwaldispuehl]

Adds a new clientConfig configuration section for client file configuration. The first two items in the new section are:

• clientconfig-dns-servers: Allows to override the DNS servers to be written into the downloadable wg-quick client configuration file.
• clientconfig-dns-search-domain: Allows to override the DNS search domain to be written into the downloadable wg-quick client configuration file.

DNS configuration according to: https://manpages.debian.org/unstable/wireguard-tools/wg-quick.8.en.html

DNS — a comma-separated list of IP (v4 or v6) addresses to be set as the interface's DNS servers, or non-IP hostnames to be set as the interface's DNS search domains. May be specified multiple times. Upon bringing the interface up, this runs resolvconf -a tun.INTERFACE -m 0 -x and upon bringing it down, this runs resolvconf -d tun.INTERFACE. If these particular invocations of resolvconf(8) are undesirable, the PostUp and PostDown keys below may be used instead.

---

Sample wg-access-server configuration file extract:

...
clientConfig:
  dnsServers:
    - 10.10.20.80
    - 9.9.9.9
    - 2001:4860:4860::8888
  dnsSearchDomain: mydomain.com

...

Sample matching client configuration file content:

[Interface]
...
DNS = 10.10.20.80, 9.9.9.9, 2001:4860:4860::8888, mydomain.com
...

If left empty, the default values of the server are written into the client config file field.

[mergeable]

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[GoliathLabs]

Thank you :)

Would it also be possible to add those flags to the helm charts? https://github.com/freifunkMUC/wg-access-server-chart

[nwaldispuehl]

Yes, we can add the new flags to the helm charts; I will create an issue for it.

I propose to wait with doing a new version here until we merged all pending features from our fork.