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diff --git a/branches/2.1.x/ipaddr.py b/branches/2.1.x/ipaddr.py new file mode 100644 index 0000000..ad27ae9 --- /dev/null +++ b/branches/2.1.x/ipaddr.py @@ -0,0 +1,1897 @@ +#!/usr/bin/python +# +# Copyright 2007 Google Inc. +# Licensed to PSF under a Contributor Agreement. +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or +# implied. See the License for the specific language governing +# permissions and limitations under the License. + +"""A fast, lightweight IPv4/IPv6 manipulation library in Python. + +This library is used to create/poke/manipulate IPv4 and IPv6 addresses +and networks. + +""" + +__version__ = '2.1.10' + +import struct + +IPV4LENGTH = 32 +IPV6LENGTH = 128 + + +class AddressValueError(ValueError): + """A Value Error related to the address.""" + + +class NetmaskValueError(ValueError): + """A Value Error related to the netmask.""" + + +def IPAddress(address, version=None): + """Take an IP string/int and return an object of the correct type. + + Args: + address: A string or integer, the IP address. Either IPv4 or + IPv6 addresses may be supplied; integers less than 2**32 will + be considered to be IPv4 by default. + version: An Integer, 4 or 6. If set, don't try to automatically + determine what the IP address type is. important for things + like IPAddress(1), which could be IPv4, '0.0.0.1', or IPv6, + '::1'. + + Returns: + An IPv4Address or IPv6Address object. + + Raises: + ValueError: if the string passed isn't either a v4 or a v6 + address. + + """ + if version: + if version == 4: + return IPv4Address(address) + elif version == 6: + return IPv6Address(address) + + try: + return IPv4Address(address) + except (AddressValueError, NetmaskValueError): + pass + + try: + return IPv6Address(address) + except (AddressValueError, NetmaskValueError): + pass + + raise ValueError('%r does not appear to be an IPv4 or IPv6 address' % + address) + + +def IPNetwork(address, version=None, strict=False): + """Take an IP string/int and return an object of the correct type. + + Args: + address: A string or integer, the IP address. Either IPv4 or + IPv6 addresses may be supplied; integers less than 2**32 will + be considered to be IPv4 by default. + version: An Integer, if set, don't try to automatically + determine what the IP address type is. important for things + like IPNetwork(1), which could be IPv4, '0.0.0.1/32', or IPv6, + '::1/128'. + + Returns: + An IPv4Network or IPv6Network object. + + Raises: + ValueError: if the string passed isn't either a v4 or a v6 + address. Or if a strict network was requested and a strict + network wasn't given. + + """ + if version: + if version == 4: + return IPv4Network(address, strict) + elif version == 6: + return IPv6Network(address, strict) + + try: + return IPv4Network(address, strict) + except (AddressValueError, NetmaskValueError): + pass + + try: + return IPv6Network(address, strict) + except (AddressValueError, NetmaskValueError): + pass + + raise ValueError('%r does not appear to be an IPv4 or IPv6 network' % + address) + + +def v4_int_to_packed(address): + """The binary representation of this address. + + Args: + address: An integer representation of an IPv4 IP address. + + Returns: + The binary representation of this address. + + Raises: + ValueError: If the integer is too large to be an IPv4 IP + address. + """ + if address > _BaseV4._ALL_ONES: + raise ValueError('Address too large for IPv4') + return Bytes(struct.pack('!I', address)) + + +def v6_int_to_packed(address): + """The binary representation of this address. + + Args: + address: An integer representation of an IPv4 IP address. + + Returns: + The binary representation of this address. + """ + return Bytes(struct.pack('!QQ', address >> 64, address & (2**64 - 1))) + + +def _find_address_range(addresses): + """Find a sequence of addresses. + + Args: + addresses: a list of IPv4 or IPv6 addresses. + + Returns: + A tuple containing the first and last IP addresses in the sequence. + + """ + first = last = addresses[0] + for ip in addresses[1:]: + if ip._ip == last._ip + 1: + last = ip + else: + break + return (first, last) + +def _get_prefix_length(number1, number2, bits): + """Get the number of leading bits that are same for two numbers. + + Args: + number1: an integer. + number2: another integer. + bits: the maximum number of bits to compare. + + Returns: + The number of leading bits that are the same for two numbers. + + """ + for i in range(bits): + if number1 >> i == number2 >> i: + return bits - i + return 0 + +def _count_righthand_zero_bits(number, bits): + """Count the number of zero bits on the right hand side. + + Args: + number: an integer. + bits: maximum number of bits to count. + + Returns: + The number of zero bits on the right hand side of the number. + + """ + if number == 0: + return bits + for i in range(bits): + if (number >> i) % 2: + return i + +def summarize_address_range(first, last): + """Summarize a network range given the first and last IP addresses. + + Example: + >>> summarize_address_range(IPv4Address('1.1.1.0'), + IPv4Address('1.1.1.130')) + [IPv4Network('1.1.1.0/25'), IPv4Network('1.1.1.128/31'), + IPv4Network('1.1.1.130/32')] + + Args: + first: the first IPv4Address or IPv6Address in the range. + last: the last IPv4Address or IPv6Address in the range. + + Returns: + The address range collapsed to a list of IPv4Network's or + IPv6Network's. + + Raise: + TypeError: + If the first and last objects are not IP addresses. + If the first and last objects are not the same version. + ValueError: + If the last object is not greater than the first. + If the version is not 4 or 6. + + """ + if not (isinstance(first, _BaseIP) and isinstance(last, _BaseIP)): + raise TypeError('first and last must be IP addresses, not networks') + if first.version != last.version: + raise TypeError("%s and %s are not of the same version" % ( + str(first), str(last))) + if first > last: + raise ValueError('last IP address must be greater than first') + + networks = [] + + if first.version == 4: + ip = IPv4Network + elif first.version == 6: + ip = IPv6Network + else: + raise ValueError('unknown IP version') + + ip_bits = first._max_prefixlen + first_int = first._ip + last_int = last._ip + while first_int <= last_int: + nbits = _count_righthand_zero_bits(first_int, ip_bits) + current = None + while nbits >= 0: + addend = 2**nbits - 1 + current = first_int + addend + nbits -= 1 + if current <= last_int: + break + prefix = _get_prefix_length(first_int, current, ip_bits) + net = ip('%s/%d' % (str(first), prefix)) + networks.append(net) + if current == ip._ALL_ONES: + break + first_int = current + 1 + first = IPAddress(first_int, version=first._version) + return networks + +def _collapse_address_list_recursive(addresses): + """Loops through the addresses, collapsing concurrent netblocks. + + Example: + + ip1 = IPv4Network('1.1.0.0/24') + ip2 = IPv4Network('1.1.1.0/24') + ip3 = IPv4Network('1.1.2.0/24') + ip4 = IPv4Network('1.1.3.0/24') + ip5 = IPv4Network('1.1.4.0/24') + ip6 = IPv4Network('1.1.0.1/22') + + _collapse_address_list_recursive([ip1, ip2, ip3, ip4, ip5, ip6]) -> + [IPv4Network('1.1.0.0/22'), IPv4Network('1.1.4.0/24')] + + This shouldn't be called directly; it is called via + collapse_address_list([]). + + Args: + addresses: A list of IPv4Network's or IPv6Network's + + Returns: + A list of IPv4Network's or IPv6Network's depending on what we were + passed. + + """ + ret_array = [] + optimized = False + + for cur_addr in addresses: + if not ret_array: + ret_array.append(cur_addr) + continue + if cur_addr in ret_array[-1]: + optimized = True + elif cur_addr == ret_array[-1].supernet().subnet()[1]: + ret_array.append(ret_array.pop().supernet()) + optimized = True + else: + ret_array.append(cur_addr) + + if optimized: + return _collapse_address_list_recursive(ret_array) + + return ret_array + + +def collapse_address_list(addresses): + """Collapse a list of IP objects. + + Example: + collapse_address_list([IPv4('1.1.0.0/24'), IPv4('1.1.1.0/24')]) -> + [IPv4('1.1.0.0/23')] + + Args: + addresses: A list of IPv4Network or IPv6Network objects. + + Returns: + A list of IPv4Network or IPv6Network objects depending on what we + were passed. + + Raises: + TypeError: If passed a list of mixed version objects. + + """ + i = 0 + addrs = [] + ips = [] + nets = [] + + # split IP addresses and networks + for ip in addresses: + if isinstance(ip, _BaseIP): + if ips and ips[-1]._version != ip._version: + raise TypeError("%s and %s are not of the same version" % ( + str(ip), str(ips[-1]))) + ips.append(ip) + elif ip._prefixlen == ip._max_prefixlen: + if ips and ips[-1]._version != ip._version: + raise TypeError("%s and %s are not of the same version" % ( + str(ip), str(ips[-1]))) + ips.append(ip.ip) + else: + if nets and nets[-1]._version != ip._version: + raise TypeError("%s and %s are not of the same version" % ( + str(ip), str(ips[-1]))) + nets.append(ip) + + # sort and dedup + ips = sorted(set(ips)) + nets = sorted(set(nets)) + + while i < len(ips): + (first, last) = _find_address_range(ips[i:]) + i = ips.index(last) + 1 + addrs.extend(summarize_address_range(first, last)) + + return _collapse_address_list_recursive(sorted( + addrs + nets, key=_BaseNet._get_networks_key)) + +# backwards compatibility +CollapseAddrList = collapse_address_list + +# We need to distinguish between the string and packed-bytes representations +# of an IP address. For example, b'0::1' is the IPv4 address 48.58.58.49, +# while '0::1' is an IPv6 address. +# +# In Python 3, the native 'bytes' type already provides this functionality, +# so we use it directly. For earlier implementations where bytes is not a +# distinct type, we create a subclass of str to serve as a tag. +# +# Usage example (Python 2): +# ip = ipaddr.IPAddress(ipaddr.Bytes('xxxx')) +# +# Usage example (Python 3): +# ip = ipaddr.IPAddress(b'xxxx') +try: + if bytes is str: + raise TypeError("bytes is not a distinct type") + Bytes = bytes +except (NameError, TypeError): + class Bytes(str): + def __repr__(self): + return 'Bytes(%s)' % str.__repr__(self) + +def get_mixed_type_key(obj): + """Return a key suitable for sorting between networks and addresses. + + Address and Network objects are not sortable by default; they're + fundamentally different so the expression + + IPv4Address('1.1.1.1') <= IPv4Network('1.1.1.1/24') + + doesn't make any sense. There are some times however, where you may wish + to have ipaddr sort these for you anyway. If you need to do this, you + can use this function as the key= argument to sorted(). + + Args: + obj: either a Network or Address object. + Returns: + appropriate key. + + """ + if isinstance(obj, _BaseNet): + return obj._get_networks_key() + elif isinstance(obj, _BaseIP): + return obj._get_address_key() + return NotImplemented + +class _IPAddrBase(object): + + """The mother class.""" + + def __index__(self): + return self._ip + + def __int__(self): + return self._ip + + def __hex__(self): + return hex(self._ip) + + @property + def exploded(self): + """Return the longhand version of the IP address as a string.""" + return self._explode_shorthand_ip_string() + + @property + def compressed(self): + """Return the shorthand version of the IP address as a string.""" + return str(self) + + +class _BaseIP(_IPAddrBase): + + """A generic IP object. + + This IP class contains the version independent methods which are + used by single IP addresses. + + """ + + def __eq__(self, other): + try: + return (self._ip == other._ip + and self._version == other._version) + except AttributeError: + return NotImplemented + + def __ne__(self, other): + eq = self.__eq__(other) + if eq is NotImplemented: + return NotImplemented + return not eq + + def __le__(self, other): + gt = self.__gt__(other) + if gt is NotImplemented: + return NotImplemented + return not gt + + def __ge__(self, other): + lt = self.__lt__(other) + if lt is NotImplemented: + return NotImplemented + return not lt + + def __lt__(self, other): + if self._version != other._version: + raise TypeError('%s and %s are not of the same version' % ( + str(self), str(other))) + if not isinstance(other, _BaseIP): + raise TypeError('%s and %s are not of the same type' % ( + str(self), str(other))) + if self._ip != other._ip: + return self._ip < other._ip + return False + + def __gt__(self, other): + if self._version != other._version: + raise TypeError('%s and %s are not of the same version' % ( + str(self), str(other))) + if not isinstance(other, _BaseIP): + raise TypeError('%s and %s are not of the same type' % ( + str(self), str(other))) + if self._ip != other._ip: + return self._ip > other._ip + return False + + # Shorthand for Integer addition and subtraction. This is not + # meant to ever support addition/subtraction of addresses. + def __add__(self, other): + if not isinstance(other, int): + return NotImplemented + return IPAddress(int(self) + other, version=self._version) + + def __sub__(self, other): + if not isinstance(other, int): + return NotImplemented + return IPAddress(int(self) - other, version=self._version) + + def __repr__(self): + return '%s(%r)' % (self.__class__.__name__, str(self)) + + def __str__(self): + return '%s' % self._string_from_ip_int(self._ip) + + def __hash__(self): + return hash(hex(long(self._ip))) + + def _get_address_key(self): + return (self._version, self) + + @property + def version(self): + raise NotImplementedError('BaseIP has no version') + + +class _BaseNet(_IPAddrBase): + + """A generic IP object. + + This IP class contains the version independent methods which are + used by networks. + + """ + + def __init__(self, address): + self._cache = {} + + def __repr__(self): + return '%s(%r)' % (self.__class__.__name__, str(self)) + + def iterhosts(self): + """Generate Iterator over usable hosts in a network. + + This is like __iter__ except it doesn't return the network + or broadcast addresses. + + """ + cur = int(self.network) + 1 + bcast = int(self.broadcast) - 1 + while cur <= bcast: + cur += 1 + yield IPAddress(cur - 1, version=self._version) + + def __iter__(self): + cur = int(self.network) + bcast = int(self.broadcast) + while cur <= bcast: + cur += 1 + yield IPAddress(cur - 1, version=self._version) + + def __getitem__(self, n): + network = int(self.network) + broadcast = int(self.broadcast) + if n >= 0: + if network + n > broadcast: + raise IndexError + return IPAddress(network + n, version=self._version) + else: + n += 1 + if broadcast + n < network: + raise IndexError + return IPAddress(broadcast + n, version=self._version) + + def __lt__(self, other): + if self._version != other._version: + raise TypeError('%s and %s are not of the same version' % ( + str(self), str(other))) + if not isinstance(other, _BaseNet): + raise TypeError('%s and %s are not of the same type' % ( + str(self), str(other))) + if self.network != other.network: + return self.network < other.network + if self.netmask != other.netmask: + return self.netmask < other.netmask + return False + + def __gt__(self, other): + if self._version != other._version: + raise TypeError('%s and %s are not of the same version' % ( + str(self), str(other))) + if not isinstance(other, _BaseNet): + raise TypeError('%s and %s are not of the same type' % ( + str(self), str(other))) + if self.network != other.network: + return self.network > other.network + if self.netmask != other.netmask: + return self.netmask > other.netmask + return False + + def __le__(self, other): + gt = self.__gt__(other) + if gt is NotImplemented: + return NotImplemented + return not gt + + def __ge__(self, other): + lt = self.__lt__(other) + if lt is NotImplemented: + return NotImplemented + return not lt + + def __eq__(self, other): + try: + return (self._version == other._version + and self.network == other.network + and int(self.netmask) == int(other.netmask)) + except AttributeError: + if isinstance(other, _BaseIP): + return (self._version == other._version + and self._ip == other._ip) + + def __ne__(self, other): + eq = self.__eq__(other) + if eq is NotImplemented: + return NotImplemented + return not eq + + def __str__(self): + return '%s/%s' % (str(self.ip), + str(self._prefixlen)) + + def __hash__(self): + return hash(int(self.network) ^ int(self.netmask)) + + def __contains__(self, other): + # always false if one is v4 and the other is v6. + if self._version != other._version: + return False + # dealing with another network. + if isinstance(other, _BaseNet): + return (self.network <= other.network and + self.broadcast >= other.broadcast) + # dealing with another address + else: + return (int(self.network) <= int(other._ip) <= + int(self.broadcast)) + + def overlaps(self, other): + """Tell if self is partly contained in other.""" + return self.network in other or self.broadcast in other or ( + other.network in self or other.broadcast in self) + + @property + def network(self): + x = self._cache.get('network') + if x is None: + x = IPAddress(self._ip & int(self.netmask), version=self._version) + self._cache['network'] = x + return x + + @property + def broadcast(self): + x = self._cache.get('broadcast') + if x is None: + x = IPAddress(self._ip | int(self.hostmask), version=self._version) + self._cache['broadcast'] = x + return x + + @property + def hostmask(self): + x = self._cache.get('hostmask') + if x is None: + x = IPAddress(int(self.netmask) ^ self._ALL_ONES, + version=self._version) + self._cache['hostmask'] = x + return x + + @property + def with_prefixlen(self): + return '%s/%d' % (str(self.ip), self._prefixlen) + + @property + def with_netmask(self): + return '%s/%s' % (str(self.ip), str(self.netmask)) + + @property + def with_hostmask(self): + return '%s/%s' % (str(self.ip), str(self.hostmask)) + + @property + def numhosts(self): + """Number of hosts in the current subnet.""" + return int(self.broadcast) - int(self.network) + 1 + + @property + def version(self): + raise NotImplementedError('BaseNet has no version') + + @property + def prefixlen(self): + return self._prefixlen + + def address_exclude(self, other): + """Remove an address from a larger block. + + For example: + + addr1 = IPNetwork('10.1.1.0/24') + addr2 = IPNetwork('10.1.1.0/26') + addr1.address_exclude(addr2) = + [IPNetwork('10.1.1.64/26'), IPNetwork('10.1.1.128/25')] + + or IPv6: + + addr1 = IPNetwork('::1/32') + addr2 = IPNetwork('::1/128') + addr1.address_exclude(addr2) = [IPNetwork('::0/128'), + IPNetwork('::2/127'), + IPNetwork('::4/126'), + IPNetwork('::8/125'), + ... + IPNetwork('0:0:8000::/33')] + + Args: + other: An IPvXNetwork object of the same type. + + Returns: + A sorted list of IPvXNetwork objects addresses which is self + minus other. + + Raises: + TypeError: If self and other are of difffering address + versions, or if other is not a network object. + ValueError: If other is not completely contained by self. + + """ + if not self._version == other._version: + raise TypeError("%s and %s are not of the same version" % ( + str(self), str(other))) + + if not isinstance(other, _BaseNet): + raise TypeError("%s is not a network object" % str(other)) + + if other not in self: + raise ValueError('%s not contained in %s' % (str(other), + str(self))) + if other == self: + return [] + + ret_addrs = [] + + # Make sure we're comparing the network of other. + other = IPNetwork('%s/%s' % (str(other.network), str(other.prefixlen)), + version=other._version) + + s1, s2 = self.subnet() + while s1 != other and s2 != other: + if other in s1: + ret_addrs.append(s2) + s1, s2 = s1.subnet() + elif other in s2: + ret_addrs.append(s1) + s1, s2 = s2.subnet() + else: + # If we got here, there's a bug somewhere. + assert True == False, ('Error performing exclusion: ' + 's1: %s s2: %s other: %s' % + (str(s1), str(s2), str(other))) + if s1 == other: + ret_addrs.append(s2) + elif s2 == other: + ret_addrs.append(s1) + else: + # If we got here, there's a bug somewhere. + assert True == False, ('Error performing exclusion: ' + 's1: %s s2: %s other: %s' % + (str(s1), str(s2), str(other))) + + return sorted(ret_addrs, key=_BaseNet._get_networks_key) + + def compare_networks(self, other): + """Compare two IP objects. + + This is only concerned about the comparison of the integer + representation of the network addresses. This means that the + host bits aren't considered at all in this method. If you want + to compare host bits, you can easily enough do a + 'HostA._ip < HostB._ip' + + Args: + other: An IP object. + + Returns: + If the IP versions of self and other are the same, returns: + + -1 if self < other: + eg: IPv4('1.1.1.0/24') < IPv4('1.1.2.0/24') + IPv6('1080::200C:417A') < IPv6('1080::200B:417B') + 0 if self == other + eg: IPv4('1.1.1.1/24') == IPv4('1.1.1.2/24') + IPv6('1080::200C:417A/96') == IPv6('1080::200C:417B/96') + 1 if self > other + eg: IPv4('1.1.1.0/24') > IPv4('1.1.0.0/24') + IPv6('1080::1:200C:417A/112') > + IPv6('1080::0:200C:417A/112') + + If the IP versions of self and other are different, returns: + + -1 if self._version < other._version + eg: IPv4('10.0.0.1/24') < IPv6('::1/128') + 1 if self._version > other._version + eg: IPv6('::1/128') > IPv4('255.255.255.0/24') + + """ + if self._version < other._version: + return -1 + if self._version > other._version: + return 1 + # self._version == other._version below here: + if self.network < other.network: + return -1 + if self.network > other.network: + return 1 + # self.network == other.network below here: + if self.netmask < other.netmask: + return -1 + if self.netmask > other.netmask: + return 1 + # self.network == other.network and self.netmask == other.netmask + return 0 + + def _get_networks_key(self): + """Network-only key function. + + Returns an object that identifies this address' network and + netmask. This function is a suitable "key" argument for sorted() + and list.sort(). + + """ + return (self._version, self.network, self.netmask) + + def _ip_int_from_prefix(self, prefixlen=None): + """Turn the prefix length netmask into a int for comparison. + + Args: + prefixlen: An integer, the prefix length. + + Returns: + An integer. + + """ + if not prefixlen and prefixlen != 0: + prefixlen = self._prefixlen + return self._ALL_ONES ^ (self._ALL_ONES >> prefixlen) + + def _prefix_from_ip_int(self, ip_int, mask=32): + """Return prefix length from the decimal netmask. + + Args: + ip_int: An integer, the IP address. + mask: The netmask. Defaults to 32. + + Returns: + An integer, the prefix length. + + """ + while mask: + if ip_int & 1 == 1: + break + ip_int >>= 1 + mask -= 1 + + return mask + + def _ip_string_from_prefix(self, prefixlen=None): + """Turn a prefix length into a dotted decimal string. + + Args: + prefixlen: An integer, the netmask prefix length. + + Returns: + A string, the dotted decimal netmask string. + + """ + if not prefixlen: + prefixlen = self._prefixlen + return self._string_from_ip_int(self._ip_int_from_prefix(prefixlen)) + + def iter_subnets(self, prefixlen_diff=1, new_prefix=None): + """The subnets which join to make the current subnet. + + In the case that self contains only one IP + (self._prefixlen == 32 for IPv4 or self._prefixlen == 128 + for IPv6), return a list with just ourself. + + Args: + prefixlen_diff: An integer, the amount the prefix length + should be increased by. This should not be set if + new_prefix is also set. + new_prefix: The desired new prefix length. This must be a + larger number (smaller prefix) than the existing prefix. + This should not be set if prefixlen_diff is also set. + + Returns: + An iterator of IPv(4|6) objects. + + Raises: + ValueError: The prefixlen_diff is too small or too large. + OR + prefixlen_diff and new_prefix are both set or new_prefix + is a smaller number than the current prefix (smaller + number means a larger network) + + """ + if self._prefixlen == self._max_prefixlen: + yield self + return + + if new_prefix is not None: + if new_prefix < self._prefixlen: + raise ValueError('new prefix must be longer') + if prefixlen_diff != 1: + raise ValueError('cannot set prefixlen_diff and new_prefix') + prefixlen_diff = new_prefix - self._prefixlen + + if prefixlen_diff < 0: + raise ValueError('prefix length diff must be > 0') + new_prefixlen = self._prefixlen + prefixlen_diff + + if not self._is_valid_netmask(str(new_prefixlen)): + raise ValueError( + 'prefix length diff %d is invalid for netblock %s' % ( + new_prefixlen, str(self))) + + first = IPNetwork('%s/%s' % (str(self.network), + str(self._prefixlen + prefixlen_diff)), + version=self._version) + + yield first + current = first + while True: + broadcast = current.broadcast + if broadcast == self.broadcast: + return + new_addr = IPAddress(int(broadcast) + 1, version=self._version) + current = IPNetwork('%s/%s' % (str(new_addr), str(new_prefixlen)), + version=self._version) + + yield current + + def masked(self): + """Return the network object with the host bits masked out.""" + return IPNetwork('%s/%d' % (self.network, self._prefixlen), + version=self._version) + + def subnet(self, prefixlen_diff=1, new_prefix=None): + """Return a list of subnets, rather than an iterator.""" + return list(self.iter_subnets(prefixlen_diff, new_prefix)) + + def supernet(self, prefixlen_diff=1, new_prefix=None): + """The supernet containing the current network. + + Args: + prefixlen_diff: An integer, the amount the prefix length of + the network should be decreased by. For example, given a + /24 network and a prefixlen_diff of 3, a supernet with a + /21 netmask is returned. + + Returns: + An IPv4 network object. + + Raises: + ValueError: If self.prefixlen - prefixlen_diff < 0. I.e., you have a + negative prefix length. + OR + If prefixlen_diff and new_prefix are both set or new_prefix is a + larger number than the current prefix (larger number means a + smaller network) + + """ + if self._prefixlen == 0: + return self + + if new_prefix is not None: + if new_prefix > self._prefixlen: + raise ValueError('new prefix must be shorter') + if prefixlen_diff != 1: + raise ValueError('cannot set prefixlen_diff and new_prefix') + prefixlen_diff = self._prefixlen - new_prefix + + + if self.prefixlen - prefixlen_diff < 0: + raise ValueError( + 'current prefixlen is %d, cannot have a prefixlen_diff of %d' % + (self.prefixlen, prefixlen_diff)) + return IPNetwork('%s/%s' % (str(self.network), + str(self.prefixlen - prefixlen_diff)), + version=self._version) + + # backwards compatibility + Subnet = subnet + Supernet = supernet + AddressExclude = address_exclude + CompareNetworks = compare_networks + Contains = __contains__ + + +class _BaseV4(object): + + """Base IPv4 object. + + The following methods are used by IPv4 objects in both single IP + addresses and networks. + + """ + + # Equivalent to 255.255.255.255 or 32 bits of 1's. + _ALL_ONES = (2**IPV4LENGTH) - 1 + _DECIMAL_DIGITS = frozenset('0123456789') + + def __init__(self, address): + self._version = 4 + self._max_prefixlen = IPV4LENGTH + + def _explode_shorthand_ip_string(self): + return str(self) + + def _ip_int_from_string(self, ip_str): + """Turn the given IP string into an integer for comparison. + + Args: + ip_str: A string, the IP ip_str. + + Returns: + The IP ip_str as an integer. + + Raises: + AddressValueError: if ip_str isn't a valid IPv4 Address. + + """ + octets = ip_str.split('.') + if len(octets) != 4: + raise AddressValueError(ip_str) + + packed_ip = 0 + for oc in octets: + try: + packed_ip = (packed_ip << 8) | self._parse_octet(oc) + except ValueError: + raise AddressValueError(ip_str) + return packed_ip + + def _parse_octet(self, octet_str): + """Convert a decimal octet into an integer. + + Args: + octet_str: A string, the number to parse. + + Returns: + The octet as an integer. + + Raises: + ValueError: if the octet isn't strictly a decimal from [0..255]. + + """ + # Whitelist the characters, since int() allows a lot of bizarre stuff. + if not self._DECIMAL_DIGITS.issuperset(octet_str): + raise ValueError + octet_int = int(octet_str, 10) + # Disallow leading zeroes, because no clear standard exists on + # whether these should be interpreted as decimal or octal. + if octet_int > 255 or (octet_str[0] == '0' and len(octet_str) > 1): + raise ValueError + return octet_int + + def _string_from_ip_int(self, ip_int): + """Turns a 32-bit integer into dotted decimal notation. + + Args: + ip_int: An integer, the IP address. + + Returns: + The IP address as a string in dotted decimal notation. + + """ + octets = [] + for _ in xrange(4): + octets.insert(0, str(ip_int & 0xFF)) + ip_int >>= 8 + return '.'.join(octets) + + @property + def max_prefixlen(self): + return self._max_prefixlen + + @property + def packed(self): + """The binary representation of this address.""" + return v4_int_to_packed(self._ip) + + @property + def version(self): + return self._version + + @property + def is_reserved(self): + """Test if the address is otherwise IETF reserved. + + Returns: + A boolean, True if the address is within the + reserved IPv4 Network range. + + """ + return self in IPv4Network('240.0.0.0/4') + + @property + def is_private(self): + """Test if this address is allocated for private networks. + + Returns: + A boolean, True if the address is reserved per RFC 1918. + + """ + return (self in IPv4Network('10.0.0.0/8') or + self in IPv4Network('172.16.0.0/12') or + self in IPv4Network('192.168.0.0/16')) + + @property + def is_multicast(self): + """Test if the address is reserved for multicast use. + + Returns: + A boolean, True if the address is multicast. + See RFC 3171 for details. + + """ + return self in IPv4Network('224.0.0.0/4') + + @property + def is_unspecified(self): + """Test if the address is unspecified. + + Returns: + A boolean, True if this is the unspecified address as defined in + RFC 5735 3. + + """ + return self in IPv4Network('0.0.0.0') + + @property + def is_loopback(self): + """Test if the address is a loopback address. + + Returns: + A boolean, True if the address is a loopback per RFC 3330. + + """ + return self in IPv4Network('127.0.0.0/8') + + @property + def is_link_local(self): + """Test if the address is reserved for link-local. + + Returns: + A boolean, True if the address is link-local per RFC 3927. + + """ + return self in IPv4Network('169.254.0.0/16') + + +class IPv4Address(_BaseV4, _BaseIP): + + """Represent and manipulate single IPv4 Addresses.""" + + def __init__(self, address): + + """ + Args: + address: A string or integer representing the IP + '192.168.1.1' + + Additionally, an integer can be passed, so + IPv4Address('192.168.1.1') == IPv4Address(3232235777). + or, more generally + IPv4Address(int(IPv4Address('192.168.1.1'))) == + IPv4Address('192.168.1.1') + + Raises: + AddressValueError: If ipaddr isn't a valid IPv4 address. + + """ + _BaseV4.__init__(self, address) + + # Efficient constructor from integer. + if isinstance(address, (int, long)): + self._ip = address + if address < 0 or address > self._ALL_ONES: + raise AddressValueError(address) + return + + # Constructing from a packed address + if isinstance(address, Bytes): + try: + self._ip, = struct.unpack('!I', address) + except struct.error: + raise AddressValueError(address) # Wrong length. + return + + # Assume input argument to be string or any object representation + # which converts into a formatted IP string. + addr_str = str(address) + self._ip = self._ip_int_from_string(addr_str) + + +class IPv4Network(_BaseV4, _BaseNet): + + """This class represents and manipulates 32-bit IPv4 networks. + + Attributes: [examples for IPv4Network('1.2.3.4/27')] + ._ip: 16909060 + .ip: IPv4Address('1.2.3.4') + .network: IPv4Address('1.2.3.0') + .hostmask: IPv4Address('0.0.0.31') + .broadcast: IPv4Address('1.2.3.31') + .netmask: IPv4Address('255.255.255.224') + .prefixlen: 27 + + """ + + # the valid octets for host and netmasks. only useful for IPv4. + _valid_mask_octets = set((255, 254, 252, 248, 240, 224, 192, 128, 0)) + + def __init__(self, address, strict=False): + """Instantiate a new IPv4 network object. + + Args: + address: A string or integer representing the IP [& network]. + '192.168.1.1/24' + '192.168.1.1/255.255.255.0' + '192.168.1.1/0.0.0.255' + are all functionally the same in IPv4. Similarly, + '192.168.1.1' + '192.168.1.1/255.255.255.255' + '192.168.1.1/32' + are also functionaly equivalent. That is to say, failing to + provide a subnetmask will create an object with a mask of /32. + + If the mask (portion after the / in the argument) is given in + dotted quad form, it is treated as a netmask if it starts with a + non-zero field (e.g. /255.0.0.0 == /8) and as a hostmask if it + starts with a zero field (e.g. 0.255.255.255 == /8), with the + single exception of an all-zero mask which is treated as a + netmask == /0. If no mask is given, a default of /32 is used. + + Additionally, an integer can be passed, so + IPv4Network('192.168.1.1') == IPv4Network(3232235777). + or, more generally + IPv4Network(int(IPv4Network('192.168.1.1'))) == + IPv4Network('192.168.1.1') + + strict: A boolean. If true, ensure that we have been passed + A true network address, eg, 192.168.1.0/24 and not an + IP address on a network, eg, 192.168.1.1/24. + + Raises: + AddressValueError: If ipaddr isn't a valid IPv4 address. + NetmaskValueError: If the netmask isn't valid for + an IPv4 address. + ValueError: If strict was True and a network address was not + supplied. + + """ + _BaseNet.__init__(self, address) + _BaseV4.__init__(self, address) + + # Constructing from an integer or packed bytes. + if isinstance(address, (int, long, Bytes)): + self.ip = IPv4Address(address) + self._ip = self.ip._ip + self._prefixlen = self._max_prefixlen + self.netmask = IPv4Address(self._ALL_ONES) + return + + # Assume input argument to be string or any object representation + # which converts into a formatted IP prefix string. + addr = str(address).split('/') + + if len(addr) > 2: + raise AddressValueError(address) + + self._ip = self._ip_int_from_string(addr[0]) + self.ip = IPv4Address(self._ip) + + if len(addr) == 2: + mask = addr[1].split('.') + if len(mask) == 4: + # We have dotted decimal netmask. + if self._is_valid_netmask(addr[1]): + self.netmask = IPv4Address(self._ip_int_from_string( + addr[1])) + elif self._is_hostmask(addr[1]): + self.netmask = IPv4Address( + self._ip_int_from_string(addr[1]) ^ self._ALL_ONES) + else: + raise NetmaskValueError('%s is not a valid netmask' + % addr[1]) + + self._prefixlen = self._prefix_from_ip_int(int(self.netmask)) + else: + # We have a netmask in prefix length form. + if not self._is_valid_netmask(addr[1]): + raise NetmaskValueError(addr[1]) + self._prefixlen = int(addr[1]) + self.netmask = IPv4Address(self._ip_int_from_prefix( + self._prefixlen)) + else: + self._prefixlen = self._max_prefixlen + self.netmask = IPv4Address(self._ip_int_from_prefix( + self._prefixlen)) + if strict: + if self.ip != self.network: + raise ValueError('%s has host bits set' % + self.ip) + if self._prefixlen == (self._max_prefixlen - 1): + self.iterhosts = self.__iter__ + + def _is_hostmask(self, ip_str): + """Test if the IP string is a hostmask (rather than a netmask). + + Args: + ip_str: A string, the potential hostmask. + + Returns: + A boolean, True if the IP string is a hostmask. + + """ + bits = ip_str.split('.') + try: + parts = [int(x) for x in bits if int(x) in self._valid_mask_octets] + except ValueError: + return False + if len(parts) != len(bits): + return False + if parts[0] < parts[-1]: + return True + return False + + def _is_valid_netmask(self, netmask): + """Verify that the netmask is valid. + + Args: + netmask: A string, either a prefix or dotted decimal + netmask. + + Returns: + A boolean, True if the prefix represents a valid IPv4 + netmask. + + """ + mask = netmask.split('.') + if len(mask) == 4: + if [x for x in mask if int(x) not in self._valid_mask_octets]: + return False + if [y for idx, y in enumerate(mask) if idx > 0 and + y > mask[idx - 1]]: + return False + return True + try: + netmask = int(netmask) + except ValueError: + return False + return 0 <= netmask <= self._max_prefixlen + + # backwards compatibility + IsRFC1918 = lambda self: self.is_private + IsMulticast = lambda self: self.is_multicast + IsLoopback = lambda self: self.is_loopback + IsLinkLocal = lambda self: self.is_link_local + + +class _BaseV6(object): + + """Base IPv6 object. + + The following methods are used by IPv6 objects in both single IP + addresses and networks. + + """ + + _ALL_ONES = (2**IPV6LENGTH) - 1 + _HEXTET_COUNT = 8 + _HEX_DIGITS = frozenset('0123456789ABCDEFabcdef') + + def __init__(self, address): + self._version = 6 + self._max_prefixlen = IPV6LENGTH + + def _ip_int_from_string(self, ip_str): + """Turn an IPv6 ip_str into an integer. + + Args: + ip_str: A string, the IPv6 ip_str. + + Returns: + A long, the IPv6 ip_str. + + Raises: + AddressValueError: if ip_str isn't a valid IPv6 Address. + + """ + parts = ip_str.split(':') + + # An IPv6 address needs at least 2 colons (3 parts). + if len(parts) < 3: + raise AddressValueError(ip_str) + + # If the address has an IPv4-style suffix, convert it to hexadecimal. + if '.' in parts[-1]: + ipv4_int = IPv4Address(parts.pop())._ip + parts.append('%x' % ((ipv4_int >> 16) & 0xFFFF)) + parts.append('%x' % (ipv4_int & 0xFFFF)) + + # An IPv6 address can't have more than 8 colons (9 parts). + if len(parts) > self._HEXTET_COUNT + 1: + raise AddressValueError(ip_str) + + # Disregarding the endpoints, find '::' with nothing in between. + # This indicates that a run of zeroes has been skipped. + try: + skip_index, = ( + [i for i in xrange(1, len(parts) - 1) if not parts[i]] or + [None]) + except ValueError: + # Can't have more than one '::' + raise AddressValueError(ip_str) + + # parts_hi is the number of parts to copy from above/before the '::' + # parts_lo is the number of parts to copy from below/after the '::' + if skip_index is not None: + # If we found a '::', then check if it also covers the endpoints. + parts_hi = skip_index + parts_lo = len(parts) - skip_index - 1 + if not parts[0]: + parts_hi -= 1 + if parts_hi: + raise AddressValueError(ip_str) # ^: requires ^:: + if not parts[-1]: + parts_lo -= 1 + if parts_lo: + raise AddressValueError(ip_str) # :$ requires ::$ + parts_skipped = self._HEXTET_COUNT - (parts_hi + parts_lo) + if parts_skipped < 1: + raise AddressValueError(ip_str) + else: + # Otherwise, allocate the entire address to parts_hi. The endpoints + # could still be empty, but _parse_hextet() will check for that. + if len(parts) != self._HEXTET_COUNT: + raise AddressValueError(ip_str) + parts_hi = len(parts) + parts_lo = 0 + parts_skipped = 0 + + try: + # Now, parse the hextets into a 128-bit integer. + ip_int = 0L + for i in xrange(parts_hi): + ip_int <<= 16 + ip_int |= self._parse_hextet(parts[i]) + ip_int <<= 16 * parts_skipped + for i in xrange(-parts_lo, 0): + ip_int <<= 16 + ip_int |= self._parse_hextet(parts[i]) + return ip_int + except ValueError: + raise AddressValueError(ip_str) + + def _parse_hextet(self, hextet_str): + """Convert an IPv6 hextet string into an integer. + + Args: + hextet_str: A string, the number to parse. + + Returns: + The hextet as an integer. + + Raises: + ValueError: if the input isn't strictly a hex number from [0..FFFF]. + + """ + # Whitelist the characters, since int() allows a lot of bizarre stuff. + if not self._HEX_DIGITS.issuperset(hextet_str): + raise ValueError + hextet_int = int(hextet_str, 16) + if hextet_int > 0xFFFF: + raise ValueError + return hextet_int + + def _compress_hextets(self, hextets): + """Compresses a list of hextets. + + Compresses a list of strings, replacing the longest continuous + sequence of "0" in the list with "" and adding empty strings at + the beginning or at the end of the string such that subsequently + calling ":".join(hextets) will produce the compressed version of + the IPv6 address. + + Args: + hextets: A list of strings, the hextets to compress. + + Returns: + A list of strings. + + """ + best_doublecolon_start = -1 + best_doublecolon_len = 0 + doublecolon_start = -1 + doublecolon_len = 0 + for index in range(len(hextets)): + if hextets[index] == '0': + doublecolon_len += 1 + if doublecolon_start == -1: + # Start of a sequence of zeros. + doublecolon_start = index + if doublecolon_len > best_doublecolon_len: + # This is the longest sequence of zeros so far. + best_doublecolon_len = doublecolon_len + best_doublecolon_start = doublecolon_start + else: + doublecolon_len = 0 + doublecolon_start = -1 + + if best_doublecolon_len > 1: + best_doublecolon_end = (best_doublecolon_start + + best_doublecolon_len) + # For zeros at the end of the address. + if best_doublecolon_end == len(hextets): + hextets += [''] + hextets[best_doublecolon_start:best_doublecolon_end] = [''] + # For zeros at the beginning of the address. + if best_doublecolon_start == 0: + hextets = [''] + hextets + + return hextets + + def _string_from_ip_int(self, ip_int=None): + """Turns a 128-bit integer into hexadecimal notation. + + Args: + ip_int: An integer, the IP address. + + Returns: + A string, the hexadecimal representation of the address. + + Raises: + ValueError: The address is bigger than 128 bits of all ones. + + """ + if not ip_int and ip_int != 0: + ip_int = int(self._ip) + + if ip_int > self._ALL_ONES: + raise ValueError('IPv6 address is too large') + + hex_str = '%032x' % ip_int + hextets = [] + for x in range(0, 32, 4): + hextets.append('%x' % int(hex_str[x:x+4], 16)) + + hextets = self._compress_hextets(hextets) + return ':'.join(hextets) + + def _explode_shorthand_ip_string(self): + """Expand a shortened IPv6 address. + + Args: + ip_str: A string, the IPv6 address. + + Returns: + A string, the expanded IPv6 address. + + """ + if isinstance(self, _BaseNet): + ip_str = str(self.ip) + else: + ip_str = str(self) + + ip_int = self._ip_int_from_string(ip_str) + parts = [] + for i in xrange(self._HEXTET_COUNT): + parts.append('%04x' % (ip_int & 0xFFFF)) + ip_int >>= 16 + parts.reverse() + if isinstance(self, _BaseNet): + return '%s/%d' % (':'.join(parts), self.prefixlen) + return ':'.join(parts) + + @property + def max_prefixlen(self): + return self._max_prefixlen + + @property + def packed(self): + """The binary representation of this address.""" + return v6_int_to_packed(self._ip) + + @property + def version(self): + return self._version + + @property + def is_multicast(self): + """Test if the address is reserved for multicast use. + + Returns: + A boolean, True if the address is a multicast address. + See RFC 2373 2.7 for details. + + """ + return self in IPv6Network('ff00::/8') + + @property + def is_reserved(self): + """Test if the address is otherwise IETF reserved. + + Returns: + A boolean, True if the address is within one of the + reserved IPv6 Network ranges. + + """ + return (self in IPv6Network('::/8') or + self in IPv6Network('100::/8') or + self in IPv6Network('200::/7') or + self in IPv6Network('400::/6') or + self in IPv6Network('800::/5') or + self in IPv6Network('1000::/4') or + self in IPv6Network('4000::/3') or + self in IPv6Network('6000::/3') or + self in IPv6Network('8000::/3') or + self in IPv6Network('A000::/3') or + self in IPv6Network('C000::/3') or + self in IPv6Network('E000::/4') or + self in IPv6Network('F000::/5') or + self in IPv6Network('F800::/6') or + self in IPv6Network('FE00::/9')) + + @property + def is_unspecified(self): + """Test if the address is unspecified. + + Returns: + A boolean, True if this is the unspecified address as defined in + RFC 2373 2.5.2. + + """ + return self._ip == 0 and getattr(self, '_prefixlen', 128) == 128 + + @property + def is_loopback(self): + """Test if the address is a loopback address. + + Returns: + A boolean, True if the address is a loopback address as defined in + RFC 2373 2.5.3. + + """ + return self._ip == 1 and getattr(self, '_prefixlen', 128) == 128 + + @property + def is_link_local(self): + """Test if the address is reserved for link-local. + + Returns: + A boolean, True if the address is reserved per RFC 4291. + + """ + return self in IPv6Network('fe80::/10') + + @property + def is_site_local(self): + """Test if the address is reserved for site-local. + + Note that the site-local address space has been deprecated by RFC 3879. + Use is_private to test if this address is in the space of unique local + addresses as defined by RFC 4193. + + Returns: + A boolean, True if the address is reserved per RFC 3513 2.5.6. + + """ + return self in IPv6Network('fec0::/10') + + @property + def is_private(self): + """Test if this address is allocated for private networks. + + Returns: + A boolean, True if the address is reserved per RFC 4193. + + """ + return self in IPv6Network('fc00::/7') + + @property + def ipv4_mapped(self): + """Return the IPv4 mapped address. + + Returns: + If the IPv6 address is a v4 mapped address, return the + IPv4 mapped address. Return None otherwise. + + """ + if (self._ip >> 32) != 0xFFFF: + return None + return IPv4Address(self._ip & 0xFFFFFFFF) + + @property + def teredo(self): + """Tuple of embedded teredo IPs. + + Returns: + Tuple of the (server, client) IPs or None if the address + doesn't appear to be a teredo address (doesn't start with + 2001::/32) + + """ + if (self._ip >> 96) != 0x20010000: + return None + return (IPv4Address((self._ip >> 64) & 0xFFFFFFFF), + IPv4Address(~self._ip & 0xFFFFFFFF)) + + @property + def sixtofour(self): + """Return the IPv4 6to4 embedded address. + + Returns: + The IPv4 6to4-embedded address if present or None if the + address doesn't appear to contain a 6to4 embedded address. + + """ + if (self._ip >> 112) != 0x2002: + return None + return IPv4Address((self._ip >> 80) & 0xFFFFFFFF) + + +class IPv6Address(_BaseV6, _BaseIP): + + """Represent and manipulate single IPv6 Addresses. + """ + + def __init__(self, address): + """Instantiate a new IPv6 address object. + + Args: + address: A string or integer representing the IP + + Additionally, an integer can be passed, so + IPv6Address('2001:4860::') == + IPv6Address(42541956101370907050197289607612071936L). + or, more generally + IPv6Address(IPv6Address('2001:4860::')._ip) == + IPv6Address('2001:4860::') + + Raises: + AddressValueError: If address isn't a valid IPv6 address. + + """ + _BaseV6.__init__(self, address) + + # Efficient constructor from integer. + if isinstance(address, (int, long)): + self._ip = address + if address < 0 or address > self._ALL_ONES: + raise AddressValueError(address) + return + + # Constructing from a packed address + if isinstance(address, Bytes): + try: + hi, lo = struct.unpack('!QQ', address) + except struct.error: + raise AddressValueError(address) # Wrong length. + self._ip = (hi << 64) | lo + return + + # Assume input argument to be string or any object representation + # which converts into a formatted IP string. + addr_str = str(address) + if not addr_str: + raise AddressValueError('') + + self._ip = self._ip_int_from_string(addr_str) + + +class IPv6Network(_BaseV6, _BaseNet): + + """This class represents and manipulates 128-bit IPv6 networks. + + Attributes: [examples for IPv6('2001:658:22A:CAFE:200::1/64')] + .ip: IPv6Address('2001:658:22a:cafe:200::1') + .network: IPv6Address('2001:658:22a:cafe::') + .hostmask: IPv6Address('::ffff:ffff:ffff:ffff') + .broadcast: IPv6Address('2001:658:22a:cafe:ffff:ffff:ffff:ffff') + .netmask: IPv6Address('ffff:ffff:ffff:ffff::') + .prefixlen: 64 + + """ + + + def __init__(self, address, strict=False): + """Instantiate a new IPv6 Network object. + + Args: + address: A string or integer representing the IPv6 network or the IP + and prefix/netmask. + '2001:4860::/128' + '2001:4860:0000:0000:0000:0000:0000:0000/128' + '2001:4860::' + are all functionally the same in IPv6. That is to say, + failing to provide a subnetmask will create an object with + a mask of /128. + + Additionally, an integer can be passed, so + IPv6Network('2001:4860::') == + IPv6Network(42541956101370907050197289607612071936L). + or, more generally + IPv6Network(IPv6Network('2001:4860::')._ip) == + IPv6Network('2001:4860::') + + strict: A boolean. If true, ensure that we have been passed + A true network address, eg, 192.168.1.0/24 and not an + IP address on a network, eg, 192.168.1.1/24. + + Raises: + AddressValueError: If address isn't a valid IPv6 address. + NetmaskValueError: If the netmask isn't valid for + an IPv6 address. + ValueError: If strict was True and a network address was not + supplied. + + """ + _BaseNet.__init__(self, address) + _BaseV6.__init__(self, address) + + # Constructing from an integer or packed bytes. + if isinstance(address, (int, long, Bytes)): + self.ip = IPv6Address(address) + self._ip = self.ip._ip + self._prefixlen = self._max_prefixlen + self.netmask = IPv6Address(self._ALL_ONES) + return + + # Assume input argument to be string or any object representation + # which converts into a formatted IP prefix string. + addr = str(address).split('/') + + if len(addr) > 2: + raise AddressValueError(address) + + self._ip = self._ip_int_from_string(addr[0]) + self.ip = IPv6Address(self._ip) + + if len(addr) == 2: + if self._is_valid_netmask(addr[1]): + self._prefixlen = int(addr[1]) + else: + raise NetmaskValueError(addr[1]) + else: + self._prefixlen = self._max_prefixlen + + self.netmask = IPv6Address(self._ip_int_from_prefix(self._prefixlen)) + + if strict: + if self.ip != self.network: + raise ValueError('%s has host bits set' % + self.ip) + if self._prefixlen == (self._max_prefixlen - 1): + self.iterhosts = self.__iter__ + + def _is_valid_netmask(self, prefixlen): + """Verify that the netmask/prefixlen is valid. + + Args: + prefixlen: A string, the netmask in prefix length format. + + Returns: + A boolean, True if the prefix represents a valid IPv6 + netmask. + + """ + try: + prefixlen = int(prefixlen) + except ValueError: + return False + return 0 <= prefixlen <= self._max_prefixlen + + @property + def with_netmask(self): + return self.with_prefixlen |