Ability to remove docker0 from setup-interfaces

Package Information

• Package name: ??? setup-interfaces (/sbin/setup-interfaces)
• Package version: latest available with Alpine Linux 3.19
• Alpine version: 3.19.1
• Alpine architecture: x86_64

Summary

When you have docker installed on Alpine Linux and want to give the user the ability to change the IP address of the appliance, you get prompted with a default of docker0 interface. Generally, probably not a good idea to have this available in this way.

Solution included.

Steps to reproduce

install docker then run /sbin/setup-interfaces

To correct I modified two functions:

from:
unconfigured_get_first() {
       ls *.noconf 2>/dev/null | head -n 1 | sed 's/.noconf//'
}

to:
unconfigured_get_first() {
    ls *.noconf 2>/dev/null | grep -v 'docker0.noconf' | head -n 1 | sed 's/.noconf//'
}

--and--

from:
unconfigured_list() {
       local list= i=
       for i in *.noconf; do
               [ -e "$i" ] || continue
               list="${list} ${i%.noconf}"
       done
       echo $list
}

to:
unconfigured_list() {
    local list=
    for i in *.noconf; do
        [ -e "$i" ] || continue
        # Exclude docker0 from the list
        if [ "$i" != "docker0.noconf" ]; then
            list="${list} ${i%.noconf}"
        fi
    done
    echo $list
}

This will prevent enumeration of docker0, and will not find it as the "first" interface