PathFinder-Client.py

#******************************************************************************
# MAC path finder - Client part
#		equivalent to traceroute but based on MAC address
# Version: 1.0
# Revision history: 
# 		1.0 - 30/06/2014 : Initial coding (Yannick Castano, Hewlett-Packard)
#
# Pre-requisite: LLDP enables on all switch to switch interfaces
#				 Management IP address configured on the lowest VLAN interface
#
# Remarks:		 This script needs more testing
#				 Any comment/feedback is welcome: castano@hp.com
#******************************************************************************
import socket
import os
import re
import sys
import termios
import time
import comware

__author__ = 'Yannick Castano'

#******************************************************************************
# Terminal input initialization (thanks to Dobias van Ingen)
#******************************************************************************
fd = sys.stdin.fileno();
new = termios.tcgetattr(fd)
new[3] = new[3] | termios.ICANON | termios.ECHO
new[6] [termios.VMIN] = 1
new[6] [termios.VTIME] = 0
termios.tcsetattr(fd, termios.TCSANOW, new)
termios.tcsendbreak(fd,0)

#******************************************************************************
# Global variables
#******************************************************************************

CLIENTPORT = 50001
SERVERPORT = 50000
TIMEOUT = 60 # seconds

#******************************************************************************
# Procedures
#******************************************************************************
def main_menu( ):
	while True:
		print "\n"
		print "Trace a MAC address: Type T"
		print "Quit :               Type Q"
		choice = raw_input("What is your choice?\n=> ")
		if choice.upper() in ['Q','T']: break
	return choice.upper()
	
def get_lldp_mgt_ip(interface):
	command = comware.CLI('display lldp local-information interface ' + interface, False)
	output = command.get_output()
	remote_ip = 'none'
	#Extracts the LLDP local IP management address
	for s in output:
		if s.find('Management address') != -1:
			# keeps only the line with the management IP address
			if '.' in s.split()[3]:
				remote_ip = s.split()[3]
	return remote_ip
	
def find_local_mac_next_if(mac):
	command = comware.CLI('display mac-address ' + mac, False)
	output = command.get_output()
	if len(output) <= 2:
		# no mac address corresponding, result is empty
		return 'none'
	else:
		# get the third line and extract the local interface
		# first line is the command, second line the header
		result = output[2].split()
		return result [3]

def find_local_arp_ip(mac):
	command = comware.CLI('display arp | include ' + mac, False)
	output = command.get_output()
	if len(output) == 1:
		# no mac address corresponding, result is empty
		return 'none'
	else:
		# get the first line and extract the IP address
		result = output[1].split()
		return result [0]

def find_lldp_neighbor(interface):
	# LLDP rule: the lowest interface ID with an IP address is used as management interface (loopback are excluded)
	command = comware.CLI('display lldp neighbor-information interface ' + interface + ' verbose', False)
	output = command.get_output()
	neighbor = ['none', 'none']
	if len(output) != 1:
		# extracts the LLDP peer name
		for s in output:
			if s.find('System name') != -1:
				neighbor[0] = s.split()[3]
		# extracts the LLDP peer IP management address
		for s in output:
			if s.find('Management address') != -1:
				# keeps only the line with the management IP address
				if '.' in s.split()[3]:
					neighbor[1] = s.split()[3]
	return neighbor

def send_tracemac_request(localhost,neighbor_ip,mac):
	# sending on UDP port 50000, any answer will be received on UDP port 50001
	sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
	sock.connect((neighbor_ip, SERVERPORT))
	sock.sendall(localhost + ' ' + mac)
	sock.close()
	return

def local_server_start(localhost):
	sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
	sock.settimeout(TIMEOUT)
	sock.bind((localhost, CLIENTPORT))
	while True:
		received_data = sock.recv(1024)
		print received_data
		if received_data == 'END': break
	sock.close()

def convert_interface_name(intf):
	# currently supports 1G, 10G and 40G interfaces
	if intf.find('XGE') != -1:
		interface = intf.replace('XGE','Ten-GigabitEthernet')
	elif intf.find('FGE') != -1:
		interface = intf.replace ('FGE', 'FortyGigE')
	elif intf.find('GE') != -1:
		interface = intf.replace ('GE', 'GigabitEthernet')
	return interface
	
#******************************************************************************
# Main code
#******************************************************************************

choice = main_menu()

# Trace MAC is requested
if choice == 'T':
	# Ask user for the MAC address
	mac = raw_input("What is the MAC address to trace?\n=> ")
	
	# Try to find if this MAC has a local ARP entry
	ip = find_local_arp_ip(mac.lower())
	if ip != 'none':
		print '[LOCAL]:\t MAC address {} has IP address {}'.format(mac,ip)

	# Find the interface where this MAC has been learned
	intf = find_local_mac_next_if(mac.lower())
	if intf == 'none':
		print '[LOCAL]:\t No corresponding MAC address on this device'
	else:
		interface = convert_interface_name(intf)
		neighbor = find_lldp_neighbor(interface)
		if neighbor[0] == 'none':
			print '[LOCAL]:\t MAC address {} is on {}'.format(mac,interface)
		else:
			print '[LOCAL]:\t MAC address {} is on {} via switch {} (IP: {})'.format(mac,interface,neighbor[0],neighbor[1])
			#find the local management IP address used on that interface
			localhost = get_lldp_mgt_ip(interface)
			#sending request to the next switch
			send_tracemac_request(localhost,neighbor[1],mac)
			#starting local server
			local_server_start(localhost)

# Quit is requested
else:
	print "Goodbye"