#!/bin/sh

# We need root to configure interface properties.
if [ "$(whoami)" != root ]
   then printf "We need root!\n"
   exit
   else

# Has the interface even been initialized? If not, do so.
   while [ ! -e /dev/cdc-wdm0 ]
      do printf  "3\n" >> /sys/devices/pci0000:00/0000:00:14.0/usb2/2-3/bConfigurationValue
   done

# Get the name of our interface.
   wif=$(ifconfig -l | tr ' ' '\n' | grep ww)

# Establish a link, but only if one is not already available.
   if [ -e /tmp/mbim-network-state-cdc-wdm0 ]
      then printf "Connection already established.\nBringing down...\n"
      printf "Closing netlink...\n"
      mbim-network /dev/cdc-wdm0 stop >> /dev/null
      printf "Bringing down interface...\n\n"
      ifconfig "${wif}" down >> /dev/null
      exit
   else printf "Turning on radio...\n"
      mbimcli --device=/dev/cdc-wdm0 --device-open-proxy --set-radio-state=on >> /dev/null
      printf "Bringing up interface...\n"
      ifconfig "${wif}" up >> /dev/null
      printf "Opening netlink...\n\n"
      mbim-network /dev/cdc-wdm0 start >> /dev/null
   fi

# Store the result of the query so that we don't have to call it constantly
   printf "Querying for network info...\n"
   mbimcli -d /dev/cdc-wdm0 -p --query-ip-configuration > /tmp/qic.tmp

# Get our IPv4.
   ip=$(sed -ne "s/IP \[0\]\: '\([0-9]*\.[0-9]*\.[0-9]*\.[0-9]*\/[0-9][0-9]\)'/\1/p" /tmp/qic.tmp | sed 's/ //g' | cut -d '/' -f 1)

# Get our CIDR netmask and convert to decimal.
   nm=255.255.255.$(((0xFFFFFFFF >> $(sed -ne "s/IP \[0\]\: '\([0-9]*\.[0-9]*\.[0-9]*\.[0-9]*\/[0-9][0-9]\)'/\1/p" /tmp/qic.tmp | sed 's/ //g' | cut -d '/' -f 2)) ^ 0xFF))

# Get our gateway.
   gw=$(sed -ne "s/Gateway: '\([0-9]*\.[0-9]*\.[0-9]*\.[0-9]*\)'/\1/p" /tmp/qic.tmp|sed 's/ //g')


# Get our MTU.
   mtu=$(sed 7!d /tmp/qic.tmp | sed -ne "s/MTU: '\([0-9]*\)'/\1/p" | sed -ne 's/ //gp')

   printf "IP is %s\nNM is %s\nGW is %s\nMTU is %s\n\n" "${ip}" "${nm}" "${gw}" "${mtu}"

# Actually set up the connection.
   printf "Assigning interface details...\n"
   ifconfig "${wif}" "${ip}" netmask "${nm}"
   printf "Routing through cellular gateway...\n"
   route add default gw "${gw}"

# Test connection.
   printf "Testing interface.\n\n"
   ping -c 4 sdf.org
   printf "\n"
   rm /tmp/qic.tmp
fi
exit