Allow DNS nameservers to be configured

src/freedombone

 # IP address of the router (gateway)
 ROUTER_IP_ADDRESS="192.168.1.254"
 
+# DNS
+NAMESERVER1='213.73.91.35'
+NAMESERVER2='85.214.20.141'
+
 # whether to route outgoing traffic through Tor
 ROUTE_THROUGH_TOR="no"
 
   echo '     --cjdns            Enable CJDNS'
   echo '     --vpass            VoIP server password'
   echo '     --vport            VoIP server port'
+  echo '     --ns1              First DNS nameserver'
+  echo '     --ns2              Second DNS nameserver'
   echo ''
   echo 'system types'
   echo '------------'
     shift
     VOIP_PORT=$1
     ;;
+    # DNS Nameserver 1
+    --ns1)
+    shift
+    NAMESERVER1=$1
+    ;;
+    # DNS Nameserver 2
+    --ns2)
+    shift
+    NAMESERVER2=$1
+    ;;
     *)
     # unknown option
     ;;
   fi
 
   if [ -f $CONFIGURATION_FILE ]; then
+      if grep -q "NAMESERVER1" $CONFIGURATION_FILE; then
+          NAMESERVER1=$(grep "NAMESERVER1" $CONFIGURATION_FILE | awk -F '=' '{print $2}')
+      fi
+      if grep -q "NAMESERVER2" $CONFIGURATION_FILE; then
+          NAMESERVER2=$(grep "NAMESERVER2" $CONFIGURATION_FILE | awk -F '=' '{print $2}')
+      fi
       if grep -q "DEBIAN_REPO" $CONFIGURATION_FILE; then
           DEBIAN_REPO=$(grep "DEBIAN_REPO" $CONFIGURATION_FILE | awk -F '=' '{print $2}')
-		  CHECK_MESSAGE="Check your internet connection, /etc/network/interfaces and /etc/resolv.conf, then delete $COMPLETION_FILE, run 'rm -fR /var/lib/apt/lists/* && apt-get update --fix-missing' and run this script again. If hash sum mismatches persist then try setting $DEBIAN_REPO to a different mirror and also change /etc/apt/sources.list."
+          CHECK_MESSAGE="Check your internet connection, /etc/network/interfaces and /etc/resolv.conf, then delete $COMPLETION_FILE, run 'rm -fR /var/lib/apt/lists/* && apt-get update --fix-missing' and run this script again. If hash sum mismatches persist then try setting $DEBIAN_REPO to a different mirror and also change /etc/apt/sources.list."
       fi
       if grep -q "VOIP_PORT" $CONFIGURATION_FILE; then
           VOIP_PORT=$(grep "VOIP_PORT" $CONFIGURATION_FILE | awk -F '=' '{print $2}')
   echo "    address $LOCAL_NETWORK_STATIC_IP_ADDRESS" >> /etc/network/interfaces
   echo '    netmask 255.255.255.0' >> /etc/network/interfaces
   echo "    gateway $ROUTER_IP_ADDRESS" >> /etc/network/interfaces
-  echo '    dns-nameservers 213.73.91.35 85.214.20.141' >> /etc/network/interfaces
+  echo "    dns-nameservers $NAMESERVER1 $NAMESERVER2" >> /etc/network/interfaces
   echo '# Example to keep MAC address between reboots' >> /etc/network/interfaces
   echo '#hwaddress ether DE:AD:BE:EF:CA:FE' >> /etc/network/interfaces
   echo '' >> /etc/network/interfaces
   fi
   echo 'domain localdomain' > /etc/resolv.conf
   echo 'search localdomain' >> /etc/resolv.conf
-  echo 'nameserver 213.73.91.35' >> /etc/resolv.conf
-  echo 'nameserver 85.214.20.141' >> /etc/resolv.conf
+  echo "nameserver $NAMESERVER1" >> /etc/resolv.conf
+  echo "nameserver $NAMESERVER2" >> /etc/resolv.conf
   echo 'configure_dns' >> $COMPLETION_FILE
 }