bazarr/libs/dns/ipv4.py

61 lines
1.9 KiB
Python

# Copyright (C) Dnspython Contributors, see LICENSE for text of ISC license
# Copyright (C) 2003-2017 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
def inet_ntoa(address):
"""Convert an IPv4 address in binary form to text form.
*address*, a ``bytes``, the IPv4 address in binary form.
Returns a ``str``.
"""
if len(address) != 4:
raise dns.exception.SyntaxError
return ('%u.%u.%u.%u' % (address[0], address[1],
address[2], address[3]))
def inet_aton(text):
"""Convert an IPv4 address in text form to binary form.
*text*, a ``str``, the IPv4 address in textual form.
Returns a ``bytes``.
"""
if not isinstance(text, bytes):
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] == ord('0'):
# No leading zeros
raise dns.exception.SyntaxError
try:
b = [int(part) for part in parts]
return struct.pack('BBBB', *b)
except Exception:
raise dns.exception.SyntaxError