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Torxed/cidr_to_netmask.py

Created January 7, 2022 15:39
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Converts a CIDR notation to netmask
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cidr_to_netmask.py
def cidr_to_netmask(cidr :int, bitlen=32) -> str:
netmask = ''
while cidr > 8:
netmask += '255.'
cidr -= 8
netmask += str(2 ** cidr - 1) # math.log(128, 2)
return netmask + ('.0' * (3 - netmask.count('.') if bitlen == 32 else 7 - netmask.count('.')))
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