netwatch.py/netaddr-0.7.10/netaddr/strategy/eui48.py

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2015-03-27 22:54:25 +00:00
#-----------------------------------------------------------------------------
# Copyright (c) 2008-2012, David P. D. Moss. All rights reserved.
#
# Released under the BSD license. See the LICENSE file for details.
#-----------------------------------------------------------------------------
"""
IEEE 48-bit EUI (MAC address) logic.
Supports numerous MAC string formats including Cisco's triple hextet as well
as bare MACs containing no delimiters.
"""
import struct as _struct
import re as _re
# Check whether we need to use fallback code or not.
try:
from socket import AF_LINK
except ImportError:
AF_LINK = 48
from netaddr.core import AddrFormatError
from netaddr.strategy import BYTES_TO_BITS as _BYTES_TO_BITS, \
valid_words as _valid_words, \
int_to_words as _int_to_words, \
words_to_int as _words_to_int, \
valid_bits as _valid_bits, \
bits_to_int as _bits_to_int, \
int_to_bits as _int_to_bits, \
valid_bin as _valid_bin, \
int_to_bin as _int_to_bin, \
bin_to_int as _bin_to_int
#: The width (in bits) of this address type.
width = 48
#: The AF_* constant value of this address type.
family = AF_LINK
#: A friendly string name address type.
family_name = 'MAC'
#: The version of this address type.
version = 48
#: The maximum integer value that can be represented by this address type.
max_int = 2 ** width - 1
#-----------------------------------------------------------------------------
# Dialect classes.
#-----------------------------------------------------------------------------
class mac_eui48(object):
"""A standard IEEE EUI-48 dialect class."""
#: The individual word size (in bits) of this address type.
word_size = 8
#: The number of words in this address type.
num_words = width // word_size
#: The maximum integer value for an individual word in this address type.
max_word = 2 ** word_size - 1
#: The separator character used between each word.
word_sep = '-'
#: The format string to be used when converting words to string values.
word_fmt = '%.2X'
#: The number base to be used when interpreting word values as integers.
word_base = 16
class mac_unix(mac_eui48):
"""A UNIX-style MAC address dialect class."""
word_size = 8
num_words = width // word_size
word_sep = ':'
word_fmt = '%x'
word_base = 16
class mac_cisco(mac_eui48):
"""A Cisco 'triple hextet' MAC address dialect class."""
word_size = 16
num_words = width // word_size
word_sep = '.'
word_fmt = '%.4x'
word_base = 16
class mac_bare(mac_eui48):
"""A bare (no delimiters) MAC address dialect class."""
word_size = 48
num_words = width // word_size
word_sep = ''
word_fmt = '%.12X'
word_base = 16
class mac_pgsql(mac_eui48):
"""A PostgreSQL style (2 x 24-bit words) MAC address dialect class."""
word_size = 24
num_words = width // word_size
word_sep = ':'
word_fmt = '%.6x'
word_base = 16
#: The default dialect to be used when not specified by the user.
DEFAULT_DIALECT = mac_eui48
#-----------------------------------------------------------------------------
#: Regular expressions to match all supported MAC address formats.
RE_MAC_FORMATS = (
# 2 bytes x 6 (UNIX, Windows, EUI-48)
'^' + ':'.join(['([0-9A-F]{1,2})'] * 6) + '$',
'^' + '-'.join(['([0-9A-F]{1,2})'] * 6) + '$',
# 4 bytes x 3 (Cisco)
'^' + ':'.join(['([0-9A-F]{1,4})'] * 3) + '$',
'^' + '-'.join(['([0-9A-F]{1,4})'] * 3) + '$',
'^' + '\.'.join(['([0-9A-F]{1,4})'] * 3) + '$',
# 6 bytes x 2 (PostgreSQL)
'^' + '-'.join(['([0-9A-F]{5,6})'] * 2) + '$',
'^' + ':'.join(['([0-9A-F]{5,6})'] * 2) + '$',
# 12 bytes (bare, no delimiters)
'^(' + ''.join(['[0-9A-F]'] * 12) + ')$',
'^(' + ''.join(['[0-9A-F]'] * 11) + ')$',
)
# For efficiency, each string regexp converted in place to its compiled
# counterpart.
RE_MAC_FORMATS = [_re.compile(_, _re.IGNORECASE) for _ in RE_MAC_FORMATS]
#-----------------------------------------------------------------------------
def valid_str(addr):
"""
:param addr: An IEEE EUI-48 (MAC) address in string form.
:return: ``True`` if MAC address string is valid, ``False`` otherwise.
"""
for regexp in RE_MAC_FORMATS:
try:
match_result = regexp.findall(addr)
if len(match_result) != 0:
return True
except TypeError:
pass
return False
#-----------------------------------------------------------------------------
def str_to_int(addr):
"""
:param addr: An IEEE EUI-48 (MAC) address in string form.
:return: An unsigned integer that is equivalent to value represented
by EUI-48/MAC string address formatted according to the dialect
settings.
"""
words = []
if hasattr(addr, 'upper'):
found_match = False
for regexp in RE_MAC_FORMATS:
match_result = regexp.findall(addr)
if len(match_result) != 0:
found_match = True
if isinstance(match_result[0], tuple):
words = match_result[0]
else:
words = (match_result[0],)
break
if not found_match:
raise AddrFormatError('%r is not a supported MAC format!' % addr)
else:
raise TypeError('%r is not str() or unicode()!' % addr)
int_val = None
if len(words) == 6:
# 2 bytes x 6 (UNIX, Windows, EUI-48)
int_val = int(''.join(['%.2x' % int(w, 16) for w in words]), 16)
elif len(words) == 3:
# 4 bytes x 3 (Cisco)
int_val = int(''.join(['%.4x' % int(w, 16) for w in words]), 16)
elif len(words) == 2:
# 6 bytes x 2 (PostgreSQL)
int_val = int(''.join(['%.6x' % int(w, 16) for w in words]), 16)
elif len(words) == 1:
# 12 bytes (bare, no delimiters)
int_val = int('%012x' % int(words[0], 16), 16)
else:
raise AddrFormatError('unexpected word count in MAC address %r!' \
% addr)
return int_val
#-----------------------------------------------------------------------------
def int_to_str(int_val, dialect=None):
"""
:param int_val: An unsigned integer.
:param dialect: (optional) a Python class defining formatting options.
:return: An IEEE EUI-48 (MAC) address string that is equivalent to
unsigned integer formatted according to the dialect settings.
"""
if dialect is None:
dialect = mac_eui48
words = int_to_words(int_val, dialect)
tokens = [dialect.word_fmt % i for i in words]
addr = dialect.word_sep.join(tokens)
return addr
#-----------------------------------------------------------------------------
def int_to_packed(int_val):
"""
:param int_val: the integer to be packed.
:return: a packed string that is equivalent to value represented by an
unsigned integer.
"""
return _struct.pack(">HI", int_val >> 32, int_val & 0xffffffff)
#-----------------------------------------------------------------------------
def packed_to_int(packed_int):
"""
:param packed_int: a packed string containing an unsigned integer.
It is assumed that string is packed in network byte order.
:return: An unsigned integer equivalent to value of network address
represented by packed binary string.
"""
words = list(_struct.unpack('>6B', packed_int))
int_val = 0
for i, num in enumerate(reversed(words)):
word = num
word = word << 8 * i
int_val = int_val | word
return int_val
#-----------------------------------------------------------------------------
def valid_words(words, dialect=None):
if dialect is None:
dialect = DEFAULT_DIALECT
return _valid_words(words, dialect.word_size, dialect.num_words)
#-----------------------------------------------------------------------------
def int_to_words(int_val, dialect=None):
if dialect is None:
dialect = DEFAULT_DIALECT
return _int_to_words(int_val, dialect.word_size, dialect.num_words)
#-----------------------------------------------------------------------------
def words_to_int(words, dialect=None):
if dialect is None:
dialect = DEFAULT_DIALECT
return _words_to_int(words, dialect.word_size, dialect.num_words)
#-----------------------------------------------------------------------------
def valid_bits(bits, dialect=None):
if dialect is None:
dialect = DEFAULT_DIALECT
return _valid_bits(bits, width, dialect.word_sep)
#-----------------------------------------------------------------------------
def bits_to_int(bits, dialect=None):
if dialect is None:
dialect = DEFAULT_DIALECT
return _bits_to_int(bits, width, dialect.word_sep)
#-----------------------------------------------------------------------------
def int_to_bits(int_val, dialect=None):
if dialect is None:
dialect = DEFAULT_DIALECT
return _int_to_bits(int_val, dialect.word_size, dialect.num_words,
dialect.word_sep)
#-----------------------------------------------------------------------------
def valid_bin(bin_val, dialect=None):
if dialect is None:
dialect = DEFAULT_DIALECT
return _valid_bin(bin_val, width)
#-----------------------------------------------------------------------------
def int_to_bin(int_val):
return _int_to_bin(int_val, width)
#-----------------------------------------------------------------------------
def bin_to_int(bin_val):
return _bin_to_int(bin_val, width)