utils.py

#!/usr/bin/python3

# Copyright (c) 2005-2022 Citrix Systems Inc.
# Copyright (c) 2023 Cloud Software Group, Inc.
#
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# with or without modification, are permitted provided
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# *   Redistributions of source code must retain the above
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#     following disclaimer.
# *   Redistributions in binary form must reproduce the above
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import socket
import struct


def cidr_to_netmask(cidr):
    netmask = (0xFFFFFFFF << (32 - cidr)) & 0xFFFFFFFF
    return socket.inet_ntoa(struct.pack('!I', netmask))