collapse_address_list is too slow

ipaddr.py

 #!/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.
 
 """An IPv4/IPv6 manipulation library in Python.
 
 This library is used to create/poke/manipulate IPv4 and IPv6 addresses
-and prefixes.
+and networks.
 
 """
 
-__version__ = '1.0.2'
+__version__ = 'trunk'
 
 import struct
 
 class Error(Exception):
 
     """Base class for exceptions."""
 
 
 class IPTypeError(Error):
 
     """Tried to perform a v4 action on v6 object or vice versa."""
 
 
 class IPAddressExclusionError(Error):
 
     """An Error we should never see occurred in address exclusion."""
 
 
-class IPv4IpValidationError(Error):
-
-    """Raised when an IPv4 address is invalid."""
+class IPAddressIPValidationError(Error):
+
+    """Raised when a single address (v4 or v6) was given a network."""
 
     def __init__(self, ip):
         Error.__init__(self)
-        self.ip = ip
+        self._ip = ip
 
     def __str__(self):
-        return repr(self.ip) + ' is not a valid IPv4 address'
-
+        return "%s is not a valid address (hint, it's probably a network)" % (
+            repr(self._ip))
+
+class IPv4IpValidationError(Error):
+
+    """Raised when an IPv4 address is invalid."""
+
+    def __init__(self, ip):
+        Error.__init__(self)
+        self._ip = ip
+
+    def __str__(self):
+        return repr(self._ip) + ' is not a valid IPv4 address'
 
 class IPv4NetmaskValidationError(Error):
 
     """Raised when a netmask is invalid."""
 
     def __init__(self, netmask):
         Error.__init__(self)
         self.netmask = netmask
 
     def __str__(self):
         return repr(self.netmask) + ' is not a valid IPv4 netmask'
 
-class IPRangeError(Error):
-
-    """Raised when an IP address range is invalid."""
 
 class IPv6IpValidationError(Error):
 
     """Raised when an IPv6 address is invalid."""
 
     def __init__(self, ip):
         Error.__init__(self)
-        self.ip = ip
+        self._ip = ip
 
     def __str__(self):
-        return repr(self.ip) + ' is not a valid IPv6 address'
+        return repr(self._ip) + ' is not a valid IPv6 network'
 
 
 class IPv6NetmaskValidationError(Error):
 
     """Raised when an IPv6 netmask is invalid."""
 
     def __init__(self, netmask):
         Error.__init__(self)
         self.netmask = netmask
 
     def __str__(self):
         return repr(self.netmask) + ' is not a valid IPv6 netmask'
 
 
 class PrefixlenDiffInvalidError(Error):
 
     """Raised when Sub/Supernets is called with a bad prefixlen_diff."""
 
     def __init__(self, error_str):
         Error.__init__(self)
         self.error_str = error_str
 
 
-def IP(ipaddr):
+def IP(address, host=False, version=None):
     """Take an IP string/int and return an object of the correct type.
 
     Args:
-        ipaddr: A string or integer, the IP address.  Either IPv4 or
+        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.
+        host: A bool indicating that a host rather than the default network
+          object should be created.
+        version: An Integer, if set, don't try to automatically
+          determine what the IP address type is. important for things
+          like IP(1), which could be IPv4 or IPv6.
 
     Returns:
         An IPv4 or IPv6 object.
 
     Raises:
         ValueError: if the string passed isn't either a v4 or a v6
           address.
 
     """
+    if version:
+        if version == 4:
+            return IPv4(address, host=host)
+        elif version == 6:
+            return IPv6(address, host=host)
 
     try:
-        return IPv4(ipaddr)
+        return IPv4(address, host=host)
     except (IPv4IpValidationError, IPv4NetmaskValidationError):
         pass
 
     try:
-        return IPv6(ipaddr)
+        return IPv6(address, host=host)
     except (IPv6IpValidationError, IPv6NetmaskValidationError):
         pass
 
     raise ValueError('%r does not appear to be an IPv4 or IPv6 address' %
-                     ipaddr)
+                     address)
+
+
+def IPv4(address, host=False):
+    """Generic IPv4 Factory function..
+
+    Return an IPv4 address or network.
+    """
+    if host:
+        return IPv4Address(address)
+    return IPv4Network(address)
+
+
+def IPv6(address, host=False):
+    """Generic IPv6 Factory function..
+
+    Return an IPv6 address or network.
+    """
+    if host:
+        return IPv6Address(address)
+    return IPv6Network(address)
 
 
 def _find_address_range(addresses):
-    """Find a sequence of 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:
+        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."""
+    """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(integer, bits):
-    """Count the number of zero bits on the right hand side."""
-    if integer == 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 (integer >> i) % 2:
+        if (number >> i) % 2:
             return i
 
-def _highest_one_bit(number):
-    """Find the highest bit set to 1."""
-    value = 0
-    while number > 0:
-        number = number >> 1
-        value += 1
-    return value
-
 def summarize_address_range(first, last):
-    """Summarize a network range given the first and last IP addresses."""
-
+    """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 IPv4 or IPv6 address in the range.
+        last: the last IPv4 or IPv6 address in the range.
+
+    Returns:
+        The address range collapsed to a list of IPv4 or IPv6 networks.
+
+    Raise:
+        IPTypeError:
+            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 IPTypeError("first and last must be IP addresses, not networks")
     if first.version != last.version:
-        raise ValueError("IP addresses must be same version")
+        raise IPTypeError("IP addresses must be same version")
     if first > last:
         raise ValueError("last IP address must be greater than first")
 
     networks = []
 
     if first.version == 4:
-        ip = IPv4
+        ip = IPv4Network
     elif first.version == 6:
-        ip = IPv6
+        ip = IPv6Network
     else:
         raise ValueError("unknown IP version")
 
-    try:
-        # shortcut if the range is on a network byte boundary
-        net = ip("%s-%s" % (first.ip_ext, last.ip_ext))
+    ip_bits = first._max_prefixlen
+    first = first._ip
+    last = last._ip
+    while first <= last:
+        nbits = _count_righthand_zero_bits(first, ip_bits)
+        current = None
+        while nbits >= 0:
+            addend = 2**nbits - 1
+            current = first + addend
+            nbits -= 1
+            if current <= last:
+                break
+        prefix = _get_prefix_length(first, current, ip_bits)
+        net = ip(first)
+        net.prefixlen = prefix
         networks.append(net)
-    except IPRangeError:
-        ip_bits = first.max_prefixlen
-        while first <= last:
-            nbits = _count_righthand_zero_bits(first.ip, ip_bits)
-            current = None
-            while True:
-                addend = 2**nbits - 1
-                current = first.ip + addend
-                nbits -= 1
-                if ip(current) <= last:
-                    break
-            prefix = _get_prefix_length(first.ip, current, ip_bits)
-            networks.append(ip('%s/%s' % (first.ip_ext, prefix)))
-            first = ip(current + 1)
-            if current == ip._ALL_ONES:
-                break
+        if current == ip._ALL_ONES:
+            break
+        first = current + 1
     return networks
 
 def _collapse_address_list_recursive(addresses):
     """Loops through the addresses, collapsing concurrent netblocks.
 
     Example:
 
         ip1 = IPv4('1.1.0.0/24')
         ip2 = IPv4('1.1.1.0/24')
         ip3 = IPv4('1.1.2.0/24')
@@ skipping 42 matching lines @@
         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 IPv4 or IPv6 objects.
 
     Returns:
         A list of IPv4 or IPv6 objects depending on what we were passed.
 
     """
-    _addresses = []
     i = 0
-    ip_bits = addresses[0].max_prefixlen
-    # filter out IP addresses, dedup, and sort
-    addrs = sorted(set([ip for ip in addresses if ip.prefixlen == ip_bits]),
-        key=BaseIP._get_networks_key)
-    nets = [ip for ip in addresses if ip.prefixlen < ip_bits]
-
-    while i < len(addrs):
-        (first, last) = _find_address_range(addrs[i:])
-        i = addrs.index(last) + 1
-        _addresses.extend(
-            [IP(ip) for ip in summarize_address_range(first, last)])
+    addrs = []
+    ips = []
+    nets = []
+    # split IP addresses and networks
+    for ip in addresses:
+        if isinstance(ip, BaseIP):
+            ips.append(ip)
+        elif ip._prefixlen == ip._max_prefixlen:
+            ips.append(ip.ip)
+        else:
+            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(_addresses + nets, key=BaseIP._get_networks_key))
+        sorted(addrs + nets, key=BaseNet._get_networks_key))
 
 # backwards compatibility
 CollapseAddrList = collapse_address_list
 
 # Test whether this Python implementation supports byte objects that
 # are not identical to str ones.
 # We need to exclude platforms where bytes == str so that we can
 # distinguish between packed representations and strings, for example
 # b'12::' (the IPv4 address 49.50.58.58) and '12::' (an IPv6 address).
 try:
     _compat_has_real_bytes = bytes != str
 except NameError: # <Python2.6
     _compat_has_real_bytes = False
 
-class BaseIP(object):
+
+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)
+
+
+class BaseIP(IPAddrBase):
 
     """A generic IP object.
 
-    This IP class contains most of the methods which are used by
-    the IPv4 and IPv6 classes.
+    This IP class contains the version independent methods which are
+    used by single IP addresses.
 
     """
 
-    def __getitem__(self, n):
-        if n >= 0:
-            if self.network + n > self.broadcast:
-                raise IndexError
-            return self._string_from_ip_int(self.network + n)
-        else:
-            n += 1
-            if self.broadcast + n < self.network:
-                raise IndexError
-            return self._string_from_ip_int(self.broadcast + n)
-
-    def __lt__(self, other):
-        try:
-            return (self.version < other.version
-                    or self.ip < other.ip
-                    or self.netmask < other.netmask)
-        except AttributeError:
-            return NotImplemented
-
-    def __gt__(self, other):
-        try:
-            return (self.version > other.version
-                    or self.ip > other.ip
-                    or self.netmask > other.netmask)
-        except AttributeError:
-            return NotImplemented
+    @property
+    def exploded(self):
+        return self._explode_shorthand_ip_string()
+
+    @property
+    def compressed(self):
+        return str(self)
+
+    def __init__(self, address):
+        if '/' in str(address):
+            raise IPAddressIPValidationError(address)
 
     def __eq__(self, other):
         try:
-            return (self.version == other.version
-                    and self.ip == other.ip
-                    and self.netmask == other.netmask)
+            return not (self._ip != other._ip
+                        or 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:
+            return self._version < other._version
+        if self._ip != other._ip:
+            return self._ip < other._ip
+        return False
+
+    def __gt__(self, other):
+        if self._version != other._version:
+            return self._version > other._version
+        if self._ip != other._ip:
+            return self._ip > other._ip
+        return False
+
     def __repr__(self):
         return '%s(%r)' % (self.__class__.__name__, str(self))
 
-    def __index__(self):
-        return self.ip
-
-    def __int__(self):
-        return self.ip
-
-    def __hex__(self):
-        return hex(int(self))
+    def __str__(self):
+        return  '%s' % self._string_from_ip_int(self._ip)
+
+    def __hash__(self):
+        return hash(self._ip)
+
+    @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 hosts in a network."""
+        cur = int(self.network)
+        bcast = int(self.broadcast)
+        while cur <= bcast:
+            cur += 1
+            yield IP(cur - 1, host=True, version=self._version)
+
+    def __iter__(self):
+        self._cur = int(self.network)
+        return self
+
+    def next(self):
+        if self._cur > int(self.broadcast):
+            raise StopIteration
+        self._cur += 1
+        return IP(self._cur - 1, host=True, 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 IP(network + n, host=True, version=self._version)
+        else:
+            n += 1
+            if broadcast + n < network:
+                raise IndexError
+            return IP(broadcast + n, host=True,
+                      version=self._version)
+
+    def __lt__(self, other):
+        try:
+            if self._version != other._version:
+                return self._version < other._version
+            if self._ip != other._ip:
+                return self._ip < other._ip
+            if self.netmask != other.netmask:
+                return self.netmask < other.netmask
+            return False
+        except AttributeError:
+            return NotImplemented
+
+    def __gt__(self, other):
+        try:
+            if self._version != other._version:
+                return self._version > other._version
+            if self._ip != other._ip:
+                return self._ip > other._ip
+            if self.netmask != other.netmask:
+                return self.netmask > other.netmask
+            return False
+        except AttributeError:
+            return NotImplemented
+
+    def __eq__(self, other):
+        try:
+            return (self._version == other._version
+                    and self._ip == other._ip
+                    and int(self.netmask) == int(other.netmask))
+        except AttributeError:
+            return NotImplemented
+
+    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(self._ip ^ int(self.netmask))
+
+    def __contains__(self, other):
+        # Easy case, dealing with networks.
+        if isinstance(other, BaseNet):
+            return (int(self.network) <= int(other._ip) and
+                    int(self.broadcast) >= int(other.broadcast))
+        elif isinstance(other, BaseIP):
+            # Check if we've got an Address
+            return (int(self.network) <= int(other._ip) <=
+                    int(self.broadcast))
+        else:
+            return IP(other) in self
+
+    @property
+    def network(self):
+        x = self._cache.get('network')
+        if x is None:
+            x = IP(self._ip & int(self.netmask), host=True,
+                   version=self._version)
+            self._cache['network'] = x
+        return x
+
+    @property
+    def broadcast(self):
+        x = self._cache.get('broadcast')
+        if x is None:
+            x = IP(self._ip | int(self.hostmask), host=True,
+                   version=self._version)
+            self._cache['broadcast'] = x
+        return x
+
+    @property
+    def hostmask(self):
+        x = self._cache.get('hostmask')
+        if x is None:
+            x = IP(int(self.netmask) ^ self._ALL_ONES, host=True,
+                   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')
+
+    prefixlen = property(
+        fget=lambda self: self._prefixlen,
+        fset=lambda self, prefixlen: self._set_prefix(prefixlen))
 
     def address_exclude(self, other):
         """Remove an address from a larger block.
 
         For example:
 
             addr1 = IP('10.1.1.0/24')
             addr2 = IP('10.1.1.0/26')
             addr1.address_exclude(addr2) =
                 [IP('10.1.1.64/26'), IP('10.1.1.128/25')]
@@ skipping 18 matching lines @@
 
         Raises:
             IPTypeError: If self and other are of difffering address
               versions.
             IPAddressExclusionError: There was some unknown error in the
               address exclusion process.  This likely points to a bug
               elsewhere in this code.
             ValueError: If other is not completely contained by self.
 
         """
-        if not self.version == other.version:
+        if not self._version == other._version:
             raise IPTypeError("%s and %s aren't of the same version" % (
                 str(self), str(other)))
 
         if other not in self:
             raise ValueError('%s not contained in %s' % (str(other),
                                                          str(self)))
-
         ret_addrs = []
 
         # Make sure we're comparing the network of other.
-        other = IP(other.network_ext + '/' + str(other.prefixlen))
+        other = IP('%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.
                 raise IPAddressExclusionError('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.
             raise IPAddressExclusionError('Error performing exclusion: '
                                           's1: %s s2: %s other: %s' %
                                           (str(s1), str(s2), str(other)))
 
-        return sorted(ret_addrs, key=BaseIP._get_networks_key)
+        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'
+        '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
+            -1 if self._version < other._version
               eg: IPv4('10.0.0.1/24') < IPv6('::1/128')
-            1 if self.version > other.version
+            1 if self._version > other._version
               eg: IPv6('::1/128') > IPv4('255.255.255.0/24')
 
         """
-        if self.version < other.version:
+        if self._version < other._version:
             return -1
-        if self.version > other.version:
+        if self._version > other._version:
             return 1
-        # self.version == other.version below here:
+        # 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)
-
-    prefixlen = property(
-        fget=lambda self: self._prefixlen,
-        fset=lambda self, prefixlen: self._set_prefix(prefixlen))
-
-    def __str__(self):
-        return  '%s/%s' % (self._string_from_ip_int(self.ip),
-                           str(self.prefixlen))
-
-    def __hash__(self):
-        return hash(self.ip ^ self.netmask)
-
-    def __contains__(self, other):
-        return self.network <= other.ip and self.broadcast >= other.broadcast
-
-    @property
-    def ip_ext(self):
-        """Dotted decimal or colon string version of the IP address."""
-        return self._string_from_ip_int(self.ip)
-
-    @property
-    def ip_ext_full(self):
-        """Canonical string version of the IP address."""
-        return self.ip_ext
-
-    @property
-    def broadcast(self):
-        """Integer representation of the broadcast address."""
-        return self.ip | self.hostmask
-
-    @property
-    def broadcast_ext(self):
-        """Dotted decimal or colon string version of the broadcast."""
-        return self._string_from_ip_int(self.broadcast)
-
-    @property
-    def hostmask(self):
-        """Integer representation of the hostmask."""
-        return self.netmask ^ self._ALL_ONES
-
-    @property
-    def hostmask_ext(self):
-        """Dotted decimal or colon string version of the hostmask."""
-        return self._string_from_ip_int(self.hostmask)
-
-    @property
-    def network(self):
-        """Integer representation of the network."""
-        return self.ip & self.netmask
-
-    @property
-    def network_ext(self):
-        """Dotted decimal or colon string version of the network."""
-        return self._string_from_ip_int(self.network)
-
-    @property
-    def netmask_ext(self):
-        """Dotted decimal or colon string version of the netmask."""
-        return self._string_from_ip_int(self.netmask)
-
-    @property
-    def numhosts(self):
-        """Number of hosts in the current subnet."""
-        return self.broadcast - self.network + 1
-
-    @property
-    def version(self):
-        raise NotImplementedError('BaseIP has no version')
+        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
+            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:
@@ skipping 12 matching lines @@
         """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
+            prefixlen = self._prefixlen
         return self._string_from_ip_int(self._ip_int_from_prefix(prefixlen))
 
     # backwards compatibility
     AddressExclude = address_exclude
     CompareNetworks = compare_networks
     Contains = __contains__
     def set_prefix(self, prefixlen): self.prefixlen = prefixlen
     SetPrefix = set_prefix
     def get_prefix(self): return self.prefixlen
 
 
-class IPv4(BaseIP):
-
-    """This class represents and manipulates 32-bit IPv4 addresses.
-
-    Attributes: [examples for IPv4('1.2.3.4/27')]
-        .ip: 16909060
-        .ip_ext: '1.2.3.4'
-        .ip_ext_full: '1.2.3.4'
-        .network: 16909056L
-        .network_ext: '1.2.3.0'
-        .hostmask: 31L (0x1F)
-        .hostmask_ext: '0.0.0.31'
-        .broadcast: 16909087L (0x102031F)
-        .broadcast_ext: '1.2.3.31'
-        .netmask: 4294967040L (0xFFFFFFE0)
-        .netmask_ext: '255.255.255.224'
-        .prefixlen: 27
+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**32) - 1
 
-    def __init__(self, ipaddr):
-        """Instantiate a new IPv4 object.
-
-        Args:
-            ipaddr: A string or integer representing the IP [& network].
+    def __init__(self, address):
+        self._version = 4
+        self._max_prefixlen = 32
+
+    def _explode_shorthand_ip_string(self, ip_str=None):
+        if not ip_str:
+            ip_str = str(self)
+        return ip_str
+
+    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.
+
+        """
+        packed_ip = 0
+        for oc in ip_str.split('.'):
+            packed_ip = (packed_ip << 8) | int(oc)
+        return packed_ip
+
+    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)
+
+    def _is_valid_ip(self, ip_str):
+        """Validate the dotted decimal notation IP/netmask string.
+
+        Args:
+            ip_str: A string, the IP ip_str.
+
+        Returns:
+            A boolean, True if the string is a valid dotted decimal IP
+            string.
+
+        """
+        octets = ip_str.split('.')
+        if len(octets) == 1:
+            # We have an integer rather than a dotted decimal IP.
+            try:
+                return int(ip_str) >= 0 and int(ip_str) <= self._ALL_ONES
+            except ValueError:
+                return False
+
+        if len(octets) != 4:
+            return False
+
+        for octet in octets:
+            try:
+                if not 0 <= int(octet) <= 255:
+                    return False
+            except ValueError:
+                return False
+        return True
+
+    @property
+    def max_prefixlen(self):
+        return self._max_prefixlen
+
+    @property
+    def packed(self):
+        """The binary representation of this address."""
+        return struct.pack('!I', self._ip)
+
+    @property
+    def version(self):
+        return self._version
+
+
+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:
+            IPv4IpValidationError: If ipaddr isn't a valid IPv4 address.
+            IPv4NetmaskValidationError: If the netmask isn't valid for
+              an IPv4 address.
+
+        """
+        BaseIP.__init__(self, address)
+        BaseV4.__init__(self, address)
+
+        # Efficient constructor from integer.
+        if isinstance(address, int) or isinstance(address, long):
+            self._ip = address
+            if address < 0 or address > self._ALL_ONES:
+                raise IPv4IpValidationError(address)
+            return
+
+        # Constructing from a packed address
+        if _compat_has_real_bytes:
+            if isinstance(address, bytes) and len(address) == 4:
+                self._ip = struct.unpack('!I', address)[0]
+                return
+
+        # we have a string
+        if not self._is_valid_ip(address):
+            raise IPv4IpValidationError(address)
+
+        self._ip = self._ip_int_from_string(address)
+
+
+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
+
+    """
+
+    def __init__(self, address):
+        """Instantiate a new IPv4 network object.
+
+        Args:
+            address: A string or integer representing the IP [& network].
               '192.168.1.1/32'
               '192.168.1.1/255.255.255.255'
               '192.168.1.1/0.0.0.255'
               '192.168.1.1'
-              '192.168.1.0-192.168.1.0'
               are all functionally the same in IPv4. That is to say,
               failing to provide a subnetmask will create an object with
               a mask of /32. A netmask of '255.255.255.255' is assumed
               to be /32 and '0.0.0.0' is assumed to be /0, even though
               other netmasks can be expressed both as host- and
               net-masks. (255.0.0.0 == 0.255.255.255)
 
               Additionally, an integer can be passed, so
-              IPv4('192.168.1.1') == IPv4(3232235777).
+              IPv4Network('192.168.1.1') == IPv4Network(3232235777).
               or, more generally
-              IPv4(IPv4('192.168.1.1').ip) == IPv4('192.168.1.1')
+              IPv4Network(int(IPv4Network('192.168.1.1'))) ==
+                IPv4Network('192.168.1.1')
 
         Raises:
             IPv4IpValidationError: If ipaddr isn't a valid IPv4 address.
             IPv4NetmaskValidationError: If the netmask isn't valid for
               an IPv4 address.
-            IPRangeError: If range of IP addresses is not valid.
-
-        """
-        BaseIP.__init__(self)
-        self._version = 4
-        self._max_prefixlen = 32
+
+        """
+        BaseNet.__init__(self, address)
+        BaseV4.__init__(self, address)
 
         # Efficient constructor from integer.
-        if isinstance(ipaddr, int) or isinstance(ipaddr, long):
-            self.ip = ipaddr
+        if isinstance(address, int) or isinstance(address, long):
+            self._ip = address
+            self.ip = IPv4Address(self._ip)
             self._prefixlen = 32
-            self.netmask = self._ALL_ONES
-            if ipaddr < 0 or ipaddr > self._ALL_ONES:
-                raise IPv4IpValidationError(ipaddr)
+            self.netmask = IPv4Address(self._ALL_ONES)
+            if address < 0 or address > self._ALL_ONES:
+                raise IPv4IpValidationError(address)
             return
 
         # Constructing from a packed address
         if _compat_has_real_bytes:
-            if isinstance(ipaddr, bytes) and len(ipaddr) == 4:
-                self.ip = struct.unpack('!I', ipaddr)[0]
+            if isinstance(address, bytes) and len(address) == 4:
+                self._ip = struct.unpack('!I', address)[0]
+                self.ip = IPv4Address(self._ip)
                 self._prefixlen = 32
-                self.netmask = self._ALL_ONES
+                self.netmask = IPv4Address(self._ALL_ONES)
                 return
-
-        # Construct network from a range e.g. 1.1.1.0-1.1.1.255
-        addr = str(ipaddr).split('-')
-
-        if len(addr) > 2:
-            raise IPv4IpValidationError(ipaddr)
-
-        if len(addr) == 2:
-            if not self._is_valid_ip(addr[0]):
-                raise IPv4IpValidationError(addr[0])
-
-            if not self._is_valid_ip(addr[1]):
-                raise IPv4IpValidationError(addr[1])
-
-            self.ip = self._ip_int_from_string(addr[0])
-
-            last = self._ip_int_from_string(addr[1])
-            if last < self.ip:
-                raise IPRangeError("last address should be greater than "
-                    "first.")
-            bits = _highest_one_bit(last - self.ip)
-            self._prefixlen = self.max_prefixlen - bits
-            self.netmask = self._ip_int_from_prefix(self._prefixlen)
-            if self.broadcast != last:
-                raise IPRangeError("range %s is not on a network byte "
-                    "boundary." % ipaddr)
-            return
 
         # Assume input argument to be string or any object representation
         # which converts into a formatted IP prefix string.
-        addr = str(ipaddr).split('/')
+        addr = str(address).split('/')
 
         if len(addr) > 2:
-            raise IPv4IpValidationError(ipaddr)
+            raise IPv4IpValidationError(address)
 
         if not self._is_valid_ip(addr[0]):
             raise IPv4IpValidationError(addr[0])
 
-        self.ip = self._ip_int_from_string(addr[0])
+        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 not self._is_valid_netmask(addr[1]):
                     raise IPv4NetmaskValidationError(addr[1])
                 if self._is_hostmask(addr[1]):
-                    self.netmask = (
+                    self.netmask = IPv4Address(
                         self._ip_int_from_string(addr[1]) ^ self._ALL_ONES)
                 else:
-                    self.netmask = self._ip_int_from_string(addr[1])
-                self._prefixlen = self._prefix_from_ip_int(self.netmask)
+                    self.netmask = IPv4Address(self._ip_int_from_string(
+                        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 IPv4NetmaskValidationError(addr[1])
                 self._prefixlen = int(addr[1])
-                self.netmask = self._ip_int_from_prefix(self._prefixlen)
+                self.netmask = IPv4Address(self._ip_int_from_prefix(
+                    self._prefixlen))
         else:
             self._prefixlen = 32
-            self.netmask = self._ip_int_from_prefix(self._prefixlen)
+            self.netmask = IPv4Address(self._ip_int_from_prefix(
+                self._prefixlen))
+
 
     def _set_prefix(self, prefixlen):
-        """Change the prefix length.
+        """Change the prefix length of an IPv4 network object.
 
         Args:
             prefixlen: An integer, the new prefix length.
 
         Raises:
             IPv4NetmaskValidationError: If prefixlen is out of bounds.
 
         """
         if not 0 <= prefixlen <= 32:
             raise IPv4NetmaskValidationError(prefixlen)
         self._prefixlen = prefixlen
-        self.netmask = self._ip_int_from_prefix(self._prefixlen)
+        self.netmask = IPv4Address(self._ip_int_from_prefix(self._prefixlen))
+        # invalidate the element cache
+        self._cache['network'] = None
+        self._cache['hostmask'] = None
+        self._cache['broadcast'] = None
 
     def subnet(self, prefixlen_diff=1):
         """The subnets which join to make the current subnet.
 
         In the case that self contains only one IP
         (self._prefixlen == 32), return a list with just ourself.
 
         Args:
             prefixlen_diff: An integer, the amount the prefix length
               should be increased by.  Given a /24 network and a
               prefixlen_diff of 3, for example, 8 subnets of size /27
               will be returned.  The default value of 1 splits the
               current network into two halves.
 
         Returns:
-            A list of IPv4 objects.
+            A list of IPv4 network objects.
 
         Raises:
             PrefixlenDiffInvalidError: The prefixlen_diff is too small
               or too large.
 
         """
         if self._prefixlen == 32:
             return [self]
 
         if prefixlen_diff < 0:
             raise PrefixlenDiffInvalidError('prefix length diff must be > 0')
-        new_prefixlen = self.prefixlen + prefixlen_diff
+        new_prefixlen = self._prefixlen + prefixlen_diff
 
         if not self._is_valid_netmask(str(new_prefixlen)):
             raise PrefixlenDiffInvalidError(
                 'prefix length diff %d is invalid for netblock %s' % (
                     new_prefixlen, str(self)))
 
-        first = IPv4(
-            self._string_from_ip_int(self.network) + '/' +
-            str(self._prefixlen + prefixlen_diff))
+        first = IPv4('%s/%s' % (str(self.network),
+                                str(self._prefixlen + prefixlen_diff)))
         subnets = [first]
         current = first
         while True:
             broadcast = current.broadcast
             if broadcast == self.broadcast:
                 break
-            current = IPv4(self._string_from_ip_int(broadcast + 1) + '/' +
-                           str(new_prefixlen))
+            current = IPv4('%d/%s' % (int(broadcast) + 1, str(new_prefixlen)))
             subnets.append(current)
 
         return subnets
 
     def supernet(self, prefixlen_diff=1):
         """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 object.
+            An IPv4 network object.
 
         Raises:
             PrefixlenDiffInvalidError: If
               self.prefixlen - prefixlen_diff < 0. I.e., you have a
               negative prefix length.
 
         """
-        if self.prefixlen == 0:
+        if self._prefixlen == 0:
             return self
         if self.prefixlen - prefixlen_diff < 0:
             raise PrefixlenDiffInvalidError(
                 'current prefixlen is %d, cannot have a prefixlen_diff of %d' %
                 (self.prefixlen, prefixlen_diff))
-        return IPv4(self.ip_ext + '/' + str(self.prefixlen - prefixlen_diff))
+        return IPv4('%s/%s' % (str(self.network),
+                               str(self.prefixlen - prefixlen_diff)))
 
     @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 IPv4('10.0.0.0/8') or
@@ skipping 23 matching lines @@
 
     @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 IPv4('169.254.0.0/16')
-
-    @property
-    def version(self):
-        return self._version
-
-    @property
-    def max_prefixlen(self):
-        return self._max_prefixlen
-
-    @property
-    def packed(self):
-        """The binary representation of this address."""
-        return struct.pack('!I', self.ip)
 
     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.
 
         """
         parts = [int(x) for x in ip_str.split('.')]
         if parts[0] < parts[-1]:
             return True
         return False
-
-    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 address.
-
-        Returns:
-            The IP address as an integer.
-
-        """
-        packed_ip = 0
-        for oc in ip_str.split('.'):
-            packed_ip = (packed_ip << 8) | int(oc)
-        return packed_ip
-
-    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)
-
-    def _is_valid_ip(self, ip_str):
-        """Validate the dotted decimal notation IP/netmask string.
-
-        Args:
-            ip_str: A string, the IP address.
-
-        Returns:
-            A boolean, True if the string is a valid dotted decimal IP
-            string.
-
-        """
-        octets = ip_str.split('.')
-        if len(octets) == 1:
-            # We have an integer rather than a dotted decimal IP.
-            try:
-                return int(ip_str) >= 0 and int(ip_str) <= self._ALL_ONES
-            except ValueError:
-                return False
-
-        if len(octets) != 4:
-            return False
-
-        for octet in octets:
-            try:
-                if not 0 <= int(octet) <= 255:
-                    return False
-            except ValueError:
-                return False
-        return True
 
     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.
 
         """
         if len(netmask.split('.')) == 4:
             return self._is_valid_ip(netmask)
         try:
             netmask = int(netmask)
         except ValueError:
             return False
         return 0 <= netmask <= 32
 
     # backwards compatibility
     Subnet = subnet
     Supernet = supernet
     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 IPv6(BaseIP):
-
-    """This class respresents and manipulates 128-bit IPv6 addresses.
-
-    Attributes: [examples for IPv6('2001:658:22A:CAFE:200::1/64')]
-        .ip: 42540616829182469433547762482097946625L
-        .ip_ext: '2001:658:22a:cafe:200::1'
-        .ip_ext_full: '2001:0658:022a:cafe:0200:0000:0000:0001'
-        .network: 42540616829182469433403647294022090752L
-        .network_ext: '2001:658:22a:cafe::'
-        .hostmask: 18446744073709551615L
-        .hostmask_ext: '::ffff:ffff:ffff:ffff'
-        .broadcast: 42540616829182469451850391367731642367L
-        .broadcast_ext: '2001:658:22a:cafe:ffff:ffff:ffff:ffff'
-        .netmask: 340282366920938463444927863358058659840L
-        .netmask_ext: 64
-        .prefixlen: 64
+
+class BaseV6(object):
+
+    """Base IPv6 object.
+
+    The following methods are used by IPv6 objects in both single IP
+    addresses and networks.
 
     """
 
     _ALL_ONES = (2**128) - 1
 
-    def __init__(self, ipaddr):
-        """Instantiate a new IPv6 object.
-
-        Args:
-            ipaddr: A string or integer representing the IP 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
-              IPv6('2001:4860::') ==
-              IPv6(42541956101370907050197289607612071936L).
-              or, more generally
-              IPv6(IPv6('2001:4860::').ip) == IPv6('2001:4860::')
-
-        Raises:
-            IPv6IpValidationError: If ipaddr isn't a valid IPv6 address.
-            IPv6NetmaskValidationError: If the netmask isn't valid for
-              an IPv6 address.
-            IPRangeError: If range of IP addresses is not valid.
-
-        """
-        BaseIP.__init__(self)
+    def __init__(self, address):
         self._version = 6
         self._max_prefixlen = 128
 
-        # Efficient constructor from integer.
-        if isinstance(ipaddr, long) or isinstance(ipaddr, int):
-            self.ip = ipaddr
-            self._prefixlen = 128
-            self.netmask = self._ALL_ONES
-            if ipaddr < 0 or ipaddr > self._ALL_ONES:
-                raise IPv6IpValidationError(ipaddr)
-            return
-
-        # Constructing from a packed address
-        if _compat_has_real_bytes:
-            if isinstance(ipaddr, bytes) and len(ipaddr) == 16:
-                tmp = struct.unpack('!QQ', ipaddr)
-                self.ip = (tmp[0] << 64) | tmp[1]
-                self._prefixlen = 128
-                self.netmask = self._ALL_ONES
-                return
-
-        addr_str = str(ipaddr)
-        if not addr_str:
-            raise IPv6IpValidationError('')
-
-        # Construct network from a range e.g. ::-::15
-        addr = addr_str.split('-')
-
-        if len(addr) > 2:
-            raise IPv6IpValidationError(ipaddr)
-
-        if len(addr) == 2:
-            if not self._is_valid_ip(addr[0]):
-                raise IPv6IpValidationError(addr[0])
-
-            if not self._is_valid_ip(addr[1]):
-                raise IPv6IpValidationError(addr[1])
-
-            self.ip = self._ip_int_from_string(addr[0])
-
-            last = self._ip_int_from_string(addr[1])
-            if last < self.ip:
-                raise IPRangeError("last address should be greater than "
-                    "first.")
-            bits = _highest_one_bit(last - self.ip)
-            self._prefixlen = self.max_prefixlen - bits
-            self.netmask = self._ip_int_from_prefix(self._prefixlen)
-            if self._ip_int_from_string(IPv6(self)[-1]) != last:
-                raise IPRangeError("range %s is not on a network byte "
-                    "boundary." % ipaddr)
-            return
-
-        # Assume input argument to be string or any object representation
-        # which converts into a formatted IP prefix string.
-        addr = addr_str.split('/')
-        if len(addr) > 1:
-            if self._is_valid_netmask(addr[1]):
-                self._prefixlen = int(addr[1])
-            else:
-                raise IPv6NetmaskValidationError(addr[1])
-        else:
-            self._prefixlen = 128
-
-        self.netmask = self._ip_int_from_prefix(self._prefixlen)
-
-        if not self._is_valid_ip(addr[0]):
-            raise IPv6IpValidationError(addr[0])
-
-        self.ip = self._ip_int_from_string(addr[0])
-
-    @property
-    def ip_ext_full(self):
-        """Returns the expanded version of the IPv6 string."""
-        return self._explode_shorthand_ip_string(self.ip_ext)
-
-    def _set_prefix(self, prefixlen):
-        """Change the prefix length.
-
-        Args:
-            prefixlen: An integer, the new prefix length.
-
-        Raises:
-            IPv6NetmaskValidationError: If prefixlen is out of bounds.
-
-        """
-        if not 0 <= prefixlen <= 128:
-            raise IPv6NetmaskValidationError(prefixlen)
-        self._prefixlen = prefixlen
-        self.netmask = self._ip_int_from_prefix(self.prefixlen)
-
-    def subnet(self, prefixlen_diff=1):
-        """The subnets which join to make the current subnet.
-
-        In the case that self contains only one IP
-        (self._prefixlen == 128), return a list with just ourself.
-
-        Args:
-            prefixlen_diff: An integer, the amount the prefix length
-              should be increased by.
-
-        Returns:
-            A list of IPv6 objects.
-
-        Raises:
-            PrefixlenDiffInvalidError: The prefixlen_diff is too small
-              or too large.
-
-        """
-        # Preserve original functionality (return [self] if
-        # self.prefixlen == 128).
-        if self.prefixlen == 128:
-            return [self]
-
-        if prefixlen_diff < 0:
-            raise PrefixlenDiffInvalidError('Prefix length diff must be > 0')
-        new_prefixlen = self.prefixlen + prefixlen_diff
-        if not self._is_valid_netmask(str(new_prefixlen)):
-            raise PrefixlenDiffInvalidError(
-                'Prefix length diff %d is invalid for netblock %s' % (
-                new_prefixlen, str(self)))
-        first = IPv6(
-            self._string_from_ip_int(self.network) + '/' +
-            str(self._prefixlen + prefixlen_diff))
-        subnets = [first]
-        current = first
-        while True:
-            broadcast = current.broadcast
-            if current.broadcast == self.broadcast:
-                break
-            current = IPv6(self._string_from_ip_int(broadcast + 1) + '/' +
-                           str(new_prefixlen))
-            subnets.append(current)
-
-        return subnets
-
-    def supernet(self, prefixlen_diff=1):
-        """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 /96
-              network and a prefixlen_diff of 3, a supernet with a /93
-              netmask is returned.
-
-        Returns:
-            An IPv6 object.
-
-        Raises:
-            PrefixlenDiffInvalidError: If
-              self._prefixlen - prefixlen_diff < 0. I.e., you have a
-              negative prefix length.
-
-        """
-        if self.prefixlen == 0:
-            return self
-        if self.prefixlen - prefixlen_diff < 0:
-            raise PrefixlenDiffInvalidError(
-                'current prefixlen is %d, cannot have a prefixlen_diff of %d' %
-                (self.prefixlen, prefixlen_diff))
-        return IPv6(self.ip_ext + '/' + str(self.prefixlen - prefixlen_diff))
-
-    @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 IPv6('ff00::/8')
-
-    @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 == IPv6('::')
-
-    @property
-    def is_loopback(self):
-        """Test if the address is a loopback adddress.
-
-        Returns:
-            A boolean, True if the address is a loopback address as defined in
-            RFC 2373 2.5.3.
-
-        """
-        return self == IPv6('::1')
-
-    @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 IPv6('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 IPv6('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 IPv6('fc00::/7')
-
-    @property
-    def version(self):
-        return self._version
-
-    @property
-    def max_prefixlen(self):
-        return self._max_prefixlen
-
-    @property
-    def packed(self):
-        """The binary representation of this address."""
-        return struct.pack('!QQ', self.ip >> 64, self.ip & (2**64 - 1))
-
-    def _is_shorthand_ip(self, ip_str=None):
-        """Determine if the address is shortened.
-
-        Args:
-            ip_str: A string, the IPv6 address.
-
-        Returns:
-            A boolean, True if the address is shortened.
-
-        """
-        if ip_str.count('::') == 1:
-            return True
-        return False
-
-    def _explode_shorthand_ip_string(self, ip_str):
-        """Expand a shortened IPv6 address.
-
-        Args:
-            ip_str: A string, the IPv6 address.
-
-        Returns:
-            A string, the expanded IPv6 address.
-
-        """
-        if self._is_shorthand_ip(ip_str):
-            new_ip = []
-            hextet = ip_str.split('::')
-            sep = len(hextet[0].split(':')) + len(hextet[1].split(':'))
-            new_ip = hextet[0].split(':')
-
-            for _ in xrange(8 - sep):
-                new_ip.append('0000')
-            new_ip += hextet[1].split(':')
-
-            # Now need to make sure every hextet is 4 lower case characters.
-            # If a hextet is < 4 characters, we've got missing leading 0's.
-            ret_ip = []
-            for hextet in new_ip:
-                ret_ip.append(('0' * (4 - len(hextet)) + hextet).lower())
-            return ':'.join(ret_ip)
-        # We've already got a longhand ip_str.
-        return ip_str
-
-    def _is_valid_ip(self, ip_str=None):
-        """Ensure we have a valid IPv6 address.
-
-        Probably not as exhaustive as it should be.
-
-        Args:
-            ip_str: A string, the IPv6 address.
-
-        Returns:
-            A boolean, True if this is a valid IPv6 address.
+    def _ip_int_from_string(self, ip_str=None):
+        """Turn an IPv6 ip_str into an integer.
+
+        Args:
+            ip_str: A string, the IPv6 ip_str.
+
+        Returns:
+            A long, the IPv6 ip_str.
 
         """
         if not ip_str:
-            ip_str = self.ip_ext
-
-        # We need to have at least one ':'.
-        if ':' not in ip_str:
-            return False
-
-        # We can only have one '::' shortener.
-        if ip_str.count('::') > 1:
-            return False
-
-        # '::' should be encompassed by start, digits or end.
-        if ':::' in ip_str:
-            return False
-
-        # A single colon can neither start nor end an address.
-        if ((ip_str.startswith(':') and not ip_str.startswith('::')) or
-                (ip_str.endswith(':') and not ip_str.endswith('::'))):
-            return False
-
-        # If we have no concatenation, we need to have 8 fields with 7 ':'.
-        if '::' not in ip_str and ip_str.count(':') != 7:
-            # We might have an IPv4 mapped address.
-            if ip_str.count('.') != 3:
-                return False
-
-        ip_str = self._explode_shorthand_ip_string(ip_str)
-
-        # Now that we have that all squared away, let's check that each of the
-        # hextets are between 0x0 and 0xFFFF.
-        for hextet in ip_str.split(':'):
-            if hextet.count('.') == 3:
-                # If we have an IPv4 mapped address, the IPv4 portion has to be
-                # at the end of the IPv6 portion.
-                if not ip_str.split(':')[-1] == hextet:
-                    return False
-                try:
-                    IPv4(hextet)
-                except IPv4IpValidationError:
-                    return False
-            elif int(hextet, 16) < 0x0 or int(hextet, 16) > 0xFFFF:
-                return False
-        return True
-
-    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 <= 128
-
-    def _ip_int_from_string(self, ip_str=None):
-        """Turn an IPv6 address into an integer.
-
-        Args:
-            ip_str: A string, the IPv6 address.
-
-        Returns:
-            A long, the IPv6 address.
-
-        """
-        if not ip_str:
-            ip_str = self.ip_ext
+            ip_str = str(self.ip)
 
         ip_int = 0
 
         fields = self._explode_shorthand_ip_string(ip_str).split(':')
 
         # Do we have an IPv4 mapped (::ffff:a.b.c.d) or compact (::a.b.c.d)
-        # address?
+        # ip_str?
         if fields[-1].count('.') == 3:
             ipv4_string = fields.pop()
-            ipv4_int = IPv4(ipv4_string).ip
+            ipv4_int = IPv4(ipv4_string)._ip
             octets = []
             for _ in xrange(2):
                 octets.append(hex(ipv4_int & 0xFFFF).lstrip('0x').rstrip('L'))
                 ipv4_int >>= 16
             fields.extend(reversed(octets))
 
         for field in fields:
             ip_int = (ip_int << 16) + int(field, 16)
 
         return ip_int
@@ skipping 52 matching lines @@
             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 = self.ip
+            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)
 
-    @property
-    def netmask_ext(self):
-        """IPv6 extended netmask.
-
-        We don't deal with netmasks in IPv6 like we do in IPv4.  This is
-        here strictly for IPv4 compatibility.  We simply return the
-        prefix length.
-
-        Returns:
-            An integer.
-
+    def _explode_shorthand_ip_string(self, ip_str=None):
+        """Expand a shortened IPv6 address.
+
+        Args:
+            ip_str: A string, the IPv6 address.
+
+        Returns:
+            A string, the expanded IPv6 address.
+
+        """
+        if not ip_str: