bazarr/libs/dns/ipv4.py

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2018-11-01 00:08:29 +08:00
# Copyright (C) 2003-2007, 2009-2011 Nominum, Inc.
#
# Permission to use, copy, modify, and distribute this software and its
# documentation for any purpose with or without fee is hereby granted,
# provided that the above copyright notice and this permission notice
# appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND NOMINUM DISCLAIMS ALL WARRANTIES
# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL NOMINUM BE LIABLE FOR
# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
# OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
"""IPv4 helper functions."""
import struct
import dns.exception
from ._compat import binary_type
def inet_ntoa(address):
"""Convert an IPv4 address in network form to text form.
@param address: The IPv4 address
@type address: string
@returns: string
"""
if len(address) != 4:
raise dns.exception.SyntaxError
if not isinstance(address, bytearray):
address = bytearray(address)
return (u'%u.%u.%u.%u' % (address[0], address[1],
address[2], address[3])).encode()
def inet_aton(text):
"""Convert an IPv4 address in text form to network form.
@param text: The IPv4 address
@type text: string
@returns: string
"""
if not isinstance(text, binary_type):
text = text.encode()
parts = text.split(b'.')
if len(parts) != 4:
raise dns.exception.SyntaxError
for part in parts:
if not part.isdigit():
raise dns.exception.SyntaxError
if len(part) > 1 and part[0] == '0':
# No leading zeros
raise dns.exception.SyntaxError
try:
bytes = [int(part) for part in parts]
return struct.pack('BBBB', *bytes)
except:
raise dns.exception.SyntaxError