openresolv-discuss

Hi Einar

On 17/07/2019 11:19, Einar Jón wrote:
> Hi Roy
>
> This mostly works for me. I do need extra stuff to make resolv.conf
> run, but given the files below, my resolv.conf looks like this:
> # Generated by resolvconf
> nameserver 3.3.3.3 # /etc/resolvconf/resolv.conf.d/head
> search xxxxxx.com
> nameserver 192.168.2.xx
> nameserver 62.140.138.233
> nameserver 62.140.140.251
> nameserver 8.8.8.8
> nameserver 2.2.2.2 # /etc/resolvconf/resolv.conf.d/tail
>
> Bugs:
> 1) Comments are still weird.
>    - Stripped in /var/run/resolvconf/interfaces/*.udhcpc files
>    - Untouched in /etc/resolvconf/resolv.conf.d/head and tail

The head and tail files are added verbatim - not processed at all.

However, the resolv.conf files added to resolfconf are not stripped exactly.
$ resolvconf -l
# resolv.conf from foo
nameserver 8.8.8.8 #This is a comment

But they ARE stripped when sent to the subscribers. You can see this here:
$ resolvconf -v
DOMAIN=''
SEARCH=''
NAMESERVERS='8.8.8.8'
LOCALNAMESERVERS=''
DOMAINS=''

There are many reasons for this, but the most prevalent is this - what 
do we write if more than one entry has a comment?

$ resolvconf -l
# resolv.conf from foo
nameserver 8.8.8.8 #This is a comment

# resolv.conf from bar
nameserver 8.8.8.8 #This is a different comment

Which comment should be written to /etc/resolv.conf for the single 
nameserver entry from different sources?


>    - "#text" and "#" is skipped in  dns-nameservers lines of
> /etc/network/interfaces, but the rest is added as a nameserver
> 2) the last one means that I can't have a space after the # in
>    dns-nameservers 8.8.8.8 #/etc/network/interfaces.d/wwan0
> Or I will get a separate
> nameserver /etc/network/interfaces.d/wwan0
> Also " dns-nameservers 8.8.8.8 #This is a comment" throws away "#This", but adds
> nameserver 8.8.8.8
> nameserver is
> nameserver a
> nameserver comment

What shell exactly is /bin/sh for you?
I tested my fix with recent versions of dash, bash, BSD sh and it seems 
to work fine?

> Not bugs, but extra steps needed for this to work:
> 3) I need to create the /var/run/resolvconf/interfaces/*.udhcpc files
> myself (in a /usr/share/udhcpc/default.script.d/resolvconf) script

You're supposed to pipe the resolv.conf file it would have made to 
resolvconf. The Gentoo netifrc pacakge has a good udhcpc script here:
https://github.com/gentoo/netifrc/blob/master/sh/udhcpc-hook.sh.in

> 4) I need to borrow the /etc/network/if-down.d/resolvconf
> /etc/network/if-up.d/000resolvconf files from the ubuntu package.

It's possible that the comment bug you are seeing is here.
What is the output of:
resolvconf -l

Roy