#!/bin/sh
#
# neto -- Network Overview
#
# DESCRIPTION
#
#     This prints an overview of each network interface.
#
# AUTHOR
#
#     Noah Spurrier <noah@noah.org>
#
# LICENSE
#
#     This license is OSI and FSF approved as GPL-compatible.
#     This license identical to the ISC License and is registered with and
#     approved by the Open Source Initiative. For more information vist:
#         http://opensource.org/licenses/isc-license.txt
#
#     Copyright (c) 2010, Noah Spurrier <noah@noah.org>
#
#     Permission to use, copy, modify, and/or distribute this software for any
#     purpose with or without fee is hereby granted, provided that the above
#     copyright notice and this permission notice appear in all copies.
#
#     THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
#     WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
#     MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
#     ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
#     WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
#     ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
#     OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
#
# VERSION
#
#     Version 2
#

# TODO Add MANAGED state - is dhclient or NetworkManager handling this IF?
# FIXME Using iproute2 tools limits this script to Linux.
# FIXME Using /sys/class/net limits this script to Linux.
#    updown=$(ip -o addr show ${net_if} | sed -n -e "s/.*${net_if}:.*<.*\(UP\).*>.*/\1/p")
echo "---"
echo "hostname: " $(hostname)
echo "---"
#IF_LIST=$(ip -o link | sed -n -e "s/^[0-9]\+:[ ]\+\([a-zA-Z0-9.]\+\):.*/\1/p")
IF_LIST=$(ls /sys/class/net/)
(echo "if state link MAC IP"
 for net_if in ${IF_LIST}; do
    updown=$(cat /sys/class/net/${net_if}/operstate 2>/dev/null)
    [ -z ${updown} ] && updown="DOWN"
    macaddr=$(ip -o link show ${net_if} | sed -n -e "s/^.*link\/ether[ ]\+\([[:xdigit:]][[:xdigit:]]:[[:xdigit:]][[:xdigit:]]:[[:xdigit:]][[:xdigit:]]:[[:xdigit:]][[:xdigit:]]:[[:xdigit:]][[:xdigit:]]:[[:xdigit:]][[:xdigit:]]\).*/\1/p")
    [ -z ${macaddr} ] && macaddr="NO_MAC"
    ipaddr=$(ip addr show ${net_if} | sed -n -e "s/.*inet \([[:digit:]]\+\.[[:digit:]]\+\.[[:digit:]]\+\.[[:digit:]]\+\).*/\1/p")
    ipaddr=$(echo ${ipaddr})
    [ -z "${ipaddr}" ] && ipaddr="NO_IP"
    carrier=$(cat /sys/class/net/${net_if}/carrier 2>/dev/null)
    [ -z "${carrier}" ] && carrier="?"
    echo "${net_if} ${updown} ${carrier} ${macaddr} ${ipaddr}"
done ) | column -t

echo "---"
case "${OSTYPE}" in
        darwin*) # MacOS
        echo "gateway $(route -n get default | grep --only-matching -E '[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}')"
        ;;
        *) # All others
        echo "gateway $(ip route show | grep --only-matching -E 'default via [0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}')"
        ;;
esac
echo "---"
grep search /etc/resolv.conf
grep nameserver /etc/resolv.conf

# ip -o link | sed -n -e "s/^[0-9]\+:[ ]\+\([a-zA-Z0-9]\+\):.*link\/ether[ ]\+\([[:xdigit:]][[:xdigit:]]:[[:xdigit:]][[:xdigit:]]:[[:xdigit:]][[:xdigit:]]:[[:xdigit:]][[:xdigit:]]:[[:xdigit:]][[:xdigit:]]:[[:xdigit:]][[:xdigit:]]\).*/\1 \2/p"