#!/usr/bin/env ruby
$:.unshift File.join(File.expand_path(File.dirname(__FILE__)).untaint, '/..')

require 'netutils'

################################################################################
def usage
	STDERR.print "\
Usage: #{$progname} [-h] [-d] <host IP address>
Description:
	this script also locates an edge switch and a port using LLDP and/or CDP
	to which an specified host is connected.
	this script firstly locates a router that directly connects to a specified
	IP address of a host.  this script then resolves a MAC address of the IP
	address.  this script finally locates the switch and the port.
Options:
	-h:	output this help message.
	-d:	locate a directly connected router only.
Bugs:
	this script may fail to locate a host when the host is already detached
	from a network or the host does not generate any traffic for a certain
	duration.
Example:
	#{$progname} 192.168.0.1
"
        exit
end

usage if ! ARGV.size.between?(1, 2)
case ARGV[0]
when '-h'
	usage
when '-d'
	ARGV.shift
	connectedonly = true
end
usage if ARGV.size != 1

ia = ARGV[0]
usage if ia !~ /^[0-9\.]+$/

def host_locate(sw, interface, ma)
	vlan = interface_name_vlan_id(interface)
	return sw, interface if ! vlan

	sws = {}
	while true
		log_without_newline "\t#{sw.name} (#{sw.ia}) "
		ports = sw.mac_address_table_get(ma, vlan)
		if ports.size === 0
			raise "No FIB entry found for #{ma} " +
			    "on #{sw.name} (#{sw.ia})"
		end
		ports.each do |name, port|
			next if sws.has_key?(sw.name)
			sws[sw.name] = sw

			log "#{port}"

			ssw = static_neighbor_resolve(sw, port)
			if ssw
				sw = ssw
			else
				nsw = sw.neighbor_gets(port)
				if ! nsw ||
				   (nsw.type != Switch::Type::ROUTER &&
				    nsw.type != Switch::Type::SWITCH)
					return sw, port
				end
				if ! nsw.ia
					raise "ERROR: #{nsw.name} found but " +
					    "no IP address!!!"
				end
				sw = nsw
			end
			sw.login
			break
		end
	end
end

begin
	log "locating directly connected router for #{ia}... "
	sw, xia = router_locate(ia)
	if ia == xia
		log "\t\"#{sw.name}\" (#{sw.ia})"
	else
		log "\t\"department router\" (#{xia})"
	end

	exit 0 if connectedonly

	log_without_newline "resolving MAC address for #{xia}... "
	ma, vrf, interface = sw.macaddr_resolve(xia)
	log "found"
	log "\t#{xia} #{ma} on VRF \"#{vrf.name}\" #{interface}"

	log "locating MAC address #{ma}..."
	sw, port = host_locate(sw, interface, ma)
rescue => e
	log " FAILED: #{e.to_s}"
end