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@chuangbo
Created August 13, 2012 09:45
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Check if ip in cidr
#-*- coding:utf-8 -*-
# Author: @chuangbo
# For: @likexian
import socket
import struct
class CIDR:
'''Check if ip in cidr
>>> '8.8.8.8' in CIDR('8.8.8.8', 8)
True
>>> '8.8.7.8' in CIDR('8.8.8.8', 8)
False
'''
# bin(_MASK) = 0b11111111111111111111111111111111,32位1
_MASK = (1 << 32) - 1
def __init__(self, ip, mask):
ip = self.ip2int(ip)
mask = self._MASK << mask
self.cidr = ip & mask
@staticmethod
def ip2int(str):
return struct.unpack("!I",socket.inet_aton(str))[0]
def __contains__(self, ip):
return self.ip2int(ip) & self.cidr == self.cidr
if __name__ == '__main__':
import doctest
doctest.testmod()
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