[WLANware] proper location of resolv.conf

[Dan Flett]

Hi all,

I've noticed what looks like a few inconsistencies in FFF as to where 
resolv.conf actually resides.

Currently /etc/resolv.conf symlinks to /var/etc/resolv.conf (via 
/rom/etc/resolv.conf)

/sbin/ifup, which uses "INTERFACE_dns" nvram var to statically set a 
nameserver points at /etc/resolv.conf

/usr/share/udhcpc/default.script puts dhcp-learned nameservers in 
/tmp/resolv.conf

I believe the following changes should be made:
/sbin/ifup should be changed so it writes nameservers directly to 
/tmp/resolv.conf

/var/etc/resolv.conf should always symlink to /tmp/resolv.conf as a default 
in base-files - this achieves compatibility with openwrt and backwards 
compatibility with freifunk firmware

S50dnsmasq should do this:
if ff_dnsmasq != 0
*then*
delete /var/etc/resolv.conf -> /tmp/resolv.conf symlink
/var/etc/resolv.conf should = "nameserver 127.0.0.1"
and /var/etc/dnsmasq.conf should contain
"resolv-file=/tmp/resolv.conf"

Basically this achieves the following:

upstream nameservers should always be stored in /tmp/resolv.conf

if dnsmasq is not installed, the follwoing symlinks would be in place:
/etc/resolv.conf -> /rom/etc/resolv.conf -> /var/etc/resolv.conf -> 
/tmp/resolv.conf

if dnsmasq is installed and ff_dnsmasq != 0 the symlinks would work this 
way:
/etc/resolv.conf -> /rom/etc/resolv.conf -> /var/etc/resolv.conf = 
"nameserver 127.0.0.1"

this points local name resolution at dnsmasq - useful for logging, pinging 
hostnames

dnsmasq gets it's upstream nameservers from /tmp/resolv.conf

S50udhcpcd should


Cheers,

Dan