#!/usr/bin/python2
# Lets a user kill processes bound to
# ports in his assigned port range. To assign a port
# range, set the vsys_portreservation attribute for that user.
# e.g. vsys_portreservation => 61000-61005

import sys
import os
import string

vsys_config_dir = "/etc/planetlab/vsys-attributes"
slicename=sys.argv[1]
port_config=os.path.join(vsys_config_dir,slicename,"vsys_portreservation")

ports = open(port_config).read().rstrip()
(low,high) = map(lambda n:int(n),ports.split('-'))

arglines = map(string.strip, sys.stdin.readlines())
if len(arglines)<1:
    print >>sys.stderr, "Insufficient argument lines."
    sys.exit(1)

port = int(arglines[0]) # interface name

def do_kill(p):
   if (p):
       slice_info = os.popen('chcontext --ctx 1 cat /proc/%s/vinfo'%p).readlines()
       xid_info = slice_info[0]
       slice_id = xid_info.split()[1]
       os.system("vkill %s"%p)
       slice = os.popen('getent passwd %s'%slice_id).read().split(':')[0]
       mail_cmd = 'mail -s "PlanetLab notification" %s@slices.planet-lab.org -c %s@slices.planet-lab.org'%(slice,slicename)
       f = os.popen(mail_cmd,'w')
       f.write('Hi,\nOne of your processes on PlanetLab was terminated because you were using port %s, which is assigned to %s.'%(port,slicename))
       f.close()


if (low<=port<=high):
   fuser_cmd = "ncontext --nid 1 --migrate -- chcontext --ctx 1 fuser -n tcp %d 2> /dev/null"%port
   process_udp = os.popen(fuser_cmd).read().rstrip()

   fuser_cmd = "ncontext --nid 1 --migrate -- chcontext --ctx 1 fuser -n udp %d 2> /dev/null"%port
   process_tcp = os.popen(fuser_cmd).read().rstrip()

   do_kill(process_tcp.lstrip())
   do_kill(process_udp.lstrip())
   
else:
    print "%d is not in your range"%port