start splitting up

[hippotat] / hippotit / __init__.py

# -*- python -*-

import hippotit.slip as slip

import ipaddress
from ipaddress import AddressValueError

#---------- packet parsing ----------

def packet_addrs(packet):
  version = packet[0] >> 4
  if version == 4:
    addrlen = 4
    saddroff = 3*4
    factory = ipaddress.IPv4Address
  elif version == 6:
    addrlen = 16
    saddroff = 2*4
    factory = ipaddress.IPv6Address
  else:
    raise ValueError('unsupported IP version %d' % version)
  saddr = factory(packet[ saddroff           : saddroff + addrlen   ])
  daddr = factory(packet[ saddroff + addrlen : saddroff + addrlen*2 ])
  return (saddr, daddr)

#---------- address handling ----------

def ipaddr(input):
  try:
    r = ipaddress.IPv4Address(input)
  except AddressValueError:
    r = ipaddress.IPv6Address(input)
  return r

def ipnetwork(input):
  try:
    r = ipaddress.IPv4Network(input)
  except NetworkValueError:
    r = ipaddress.IPv6Network(input)
  return r