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Diffstat (limited to 'tags/1.0.0/ipaddr.py')
| -rw-r--r-- | tags/1.0.0/ipaddr.py | 1127 |
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diff --git a/tags/1.0.0/ipaddr.py b/tags/1.0.0/ipaddr.py new file mode 100644 index 0000000..816d9c5 --- /dev/null +++ b/tags/1.0.0/ipaddr.py @@ -0,0 +1,1127 @@ +#!/usr/bin/python +# +# Copyright 2007 Google Inc. +# +# 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. +""" + +__version__ = '1.0.0' + + +class Error(Exception): + """Base class for exceptions.""" + pass + + +class IPTypeError(Error): + """Tried to perform a v4 action on v6 object or vice versa.""" + pass + + +class IPAddressExclusionError(Error): + """An Error we should never see occurred in address exclusion.""" + pass + + +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 IPv6IpValidationError(Error): + """Raised when an IPv6 address is invalid.""" + + def __init__(self, ip): + Error.__init__(self) + self.ip = ip + + def __str__(self): + return repr(self.ip) + ' is not a valid IPv6 address' + + +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 an invalid prefixlen_diff.""" + + def __init__(self, error_str): + Error.__init__(self) + self.error_str = error_str + + +def IP(ipaddr): + """Take an IP string or int and return an object of the correct type. + + Args: + ipaddr: 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. + + Returns: + An IPv4 or IPv6 object. + + Raises: + ValueError: if the string passed isn't either a v4 or a v6 address. + """ + force_v4 = False + try: + if int(ipaddr) < 2**32: + force_v4 = True + except (TypeError, ValueError): + pass + + # Try v6 first because of the confusing nature of v4 in mapped in v6 + # addresses. + if not force_v4: + try: + return IPv6(ipaddr) + except (IPv6IpValidationError, IPv6NetmaskValidationError): + pass + + try: + return IPv4(ipaddr) + except (IPv4IpValidationError, IPv4NetmaskValidationError): + pass + + raise ValueError("%s doesn't appear to be an IPv4 or IPv6 address" % ipaddr) + + +def _CollapseAddressListRecursive(addresses): + """Recursively 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') + ip4 = IPv4('1.1.3.0/24') + ip5 = IPv4('1.1.4.0/24') + ip6 = IPv4('1.1.0.1/22') + + _CollapseAddressListRecursive([ip1, ip2, ip3, ip4, ip5, ip6]) -> + [IPv4('1.1.0.0/22'), IPv4('1.1.4.0/24')] + + This shouldn't be called directly; it is called via CollapseAddrList([]). + + Args: + addresses: A list of IPv4 or IPv6 objects. + + Returns: + A list of IPv4 or IPv6 objects 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 ret_array[-1].Contains(cur_addr): + 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 _CollapseAddressListRecursive(ret_array) + + return ret_array + + +def CollapseAddrList(addresses): + """Collapse a list of IP objects. + + Example: + + CollapseAddrList([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. + """ + return _CollapseAddressListRecursive(sorted(addresses, + cmp=BaseIP.CompareNetworks)) + + +class BaseIP(object): + """A generic IP object. + + This IP class contains most of the methods which are used by + the IPv4 and IPv6 classes. + """ + + def __getitem__(self, n): + if n >= 0: + if self.network + n > self.broadcast: + raise IndexError + return self._StrFromIpInt(self.network + n) + else: + if self.broadcast + n < self.network: + raise IndexError + return self._StrFromIpInt(self.broadcast + n) + + def __eq__(self, other): + try: + if self.version != other.version: + return False + except AttributeError: + raise NotImplementedError('%s is not an IP address' % repr(other)) + return self.ip == other.ip and self.netmask == other.netmask + + def __ne__(self, other): + return not self.__eq__(other) + + def __cmp__(self, other): + try: + return (cmp(self.version, other.version) or + cmp(self.ip, other.ip) or + cmp(self.prefixlen, other.prefixlen) or + 0) + except AttributeError: + return super(BaseIP, self).__cmp__(other) + + def AddressExclude(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.AddressExclude(addr2) = [IP('10.1.1.64/26'), IP('10.1.1.128/25')] + + or IPv6: + + addr1 = IP('::1/32') + addr2 = IP('::1/128') + addr1.AddressExclude(addr2) = [IP('::0/128'), + IP('::2/127'), + IP('::4/126'), + IP('::8/125'), + ... + IP('0:0:8000::/33')] + + Args: + other: An IP object of the same type. + + Returns: + A sorted list of IP objects addresses which is self minus other. + + 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: + raise IPTypeError("%s and %s aren't of the same version" % ( + str(self), str(other))) + + if not self.Contains(other): + 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)) + + s1, s2 = self.Subnet() + while s1 != other and s2 != other: + if s1.Contains(other): + ret_addrs.append(s2) + s1, s2 = s1.Subnet() + elif s2.Contains(other): + ret_addrs.append(s1) + s1, s2 = s2.Subnet() + else: + # If we got here, there's a bug somewhere. + raise IPAddressExclusionError('Error performing address 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 address exclusion: ' + 's1: %s s2: %s other: %s' % + (str(s1), str(s2), str(other))) + + return sorted(ret_addrs, cmp=BaseIP.CompareNetworks) + + def CompareNetworks(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 cmp(self.version, other.version) + + 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 __str__(self): + return '%s/%s' % (self._StrFromIpInt(self.ip), str(self.prefixlen)) + + def __hash__(self): + return hash(self.ip ^ self.netmask) + + def Contains(self, other): + """Return True if the given IP is wholly contained by the current network. + + Args: + other: An IP object. + + Returns: + A boolean. + """ + return self.network <= other.ip and self.broadcast >= other.broadcast + + __contains__ = Contains + + @property + def ip_ext(self): + return self._StrFromIpInt(self.ip) + + @property + def ip_ext_full(self): + return self.ip_ext + + @property + def broadcast(self): + """Integer representation of the broadcast address.""" + return self.ip | self.hostmask + + @property + def broadcast_ext(self): + return self._StrFromIpInt(self.broadcast) + + @property + def hostmask(self): + return self.netmask ^ self._ALL_ONES + + @property + def hostmask_ext(self): + return self._StrFromIpInt(self.hostmask) + + @property + def network(self): + return self.ip & self.netmask + + @property + def network_ext(self): + return self._StrFromIpInt(self.network) + + @property + def netmask_ext(self): + return self._StrFromIpInt(self.netmask) + + @property + def numhosts(self): + return self.broadcast - self.network + 1 + + @property + def version(self): + raise NotImplementedError('BaseIP has no version') + + def _IpIntFromPrefixlen(self, prefixlen=None): + """Turn the prefix length netmask into a int for easy 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 _PrefixlenFromIpInt(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 _IpStrFromPrefixlen(self, prefixlen=None): + """Turn a prefix length into a dotted decimal string. + + Args: + prefixlen: The netmask prefix length. + + Returns: + A string, the dotted decimal netmask string. + """ + if not prefixlen: + prefixlen = self.prefixlen + return self._StrFromIpInt(self._IpIntFromPrefixlen(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 + """ + + # 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 ]. + '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' + 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). + or, more generally + IPv4(IPv4('192.168.1.1').ip) == IPv4('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) + self._version = 4 + + # Efficient constructor from integer. + if isinstance(ipaddr, int) or isinstance(ipaddr, long): + self.ip = ipaddr + self.prefixlen = 32 + self.netmask = self._ALL_ONES + if ipaddr < 0 or ipaddr > self._ALL_ONES: + raise IPv4IpValidationError(ipaddr) + return + + # Assume input argument to be string or any object representation + # which converts into a formatted IP prefix string. + addr = str(ipaddr).split('/') + + if len(addr) > 2: + raise IPv4IpValidationError(ipaddr) + + if not self._IsValidIp(addr[0]): + raise IPv4IpValidationError(addr[0]) + + self.ip = self._IpIntFromStr(addr[0]) + + if len(addr) == 2: + mask = addr[1].split('.') + if len(mask) == 4: + # We have dotted decimal netmask. + if not self._IsValidNetmask(addr[1]): + raise IPv4NetmaskValidationError(addr[1]) + if self._IsHostMask(addr[1]): + self.netmask = self._IpIntFromStr(addr[1]) ^ self._ALL_ONES + else: + self.netmask = self._IpIntFromStr(addr[1]) + self.prefixlen = self._PrefixlenFromIpInt(self.netmask) + else: + # We have a netmask in prefix length form. + if not self._IsValidNetmask(addr[1]): + raise IPv4NetmaskValidationError(addr[1]) + self.prefixlen = int(addr[1]) + self.netmask = self._IpIntFromPrefixlen(self.prefixlen) + else: + self.prefixlen = 32 + self.netmask = self._IpIntFromPrefixlen(self.prefixlen) + + def __repr__(self): + return '<ipaddr.IPv4: %s>' % str(self) + + def SetPrefix(self, prefixlen): + """Change the prefix length. + + 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._IpIntFromPrefixlen(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 == 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. + + 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 + + if not self._IsValidNetmask(str(new_prefixlen)): + raise PrefixlenDiffInvalidError( + 'prefix length diff %d is invalid for netblock %s' % ( + new_prefixlen, str(self))) + + first = IPv4( + self._StrFromIpInt(self.network) + '/' + str(self.prefixlen + + prefixlen_diff)) + subnets = [first] + current = first + while True: + broadcast = current.broadcast + if broadcast == self.broadcast: + break + current = IPv4(self._StrFromIpInt(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. + + 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 IPv4(self.ip_ext + '/' + str(self.prefixlen - prefixlen_diff)) + + def IsRFC1918(self): + """Test if the IPv4 address is reserved per RFC1918. + + Returns: + A boolean, True if the address is reserved. + """ + return (IPv4('10.0.0.0/8').Contains(self) or + IPv4('172.16.0.0/12').Contains(self) or + IPv4('192.168.0.0/16').Contains(self)) + + def IsMulticast(self): + """Test if the address is reserved for multicast use. + + Returns: + A boolean, True if the address is multicast. + """ + return IPv4('224.0.0.0/4').Contains(self) + + def IsLoopback(self): + """Test if the address is a loopback adddress. + + Returns: + A boolean, True if the address is a loopback. + """ + return IPv4('127.0.0.0/8').Contains(self) + + def IsLinkLocal(self): + """Test if the address is reserved for LinkLocal. + + Returns: + A boolean, True if the address is link local. + """ + return IPv4('169.254.0.0/16').Contains(self) + + @property + def version(self): + return self._version + + def _IsHostMask(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 _IpIntFromStr(self, ip_str): + """Turn the given dotted decimal string into an integer for easy 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 _StrFromIpInt(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 _IsValidIp(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: + if not 0 <= int(octet) <= 255: + return False + return True + + def _IsValidNetmask(self, netmask): + """Validates the netmask is in the bounds of acceptable IPv4 netmasks. + + Args: + netmask: A string, either a prefix length or dotted decimal netmask. + + Returns: + A boolean, True if the prefix length represents a valid IPv4 netmask. + """ + if len(netmask.split('.')) == 4: + return self._IsValidIp(netmask) + try: + netmask = int(netmask) + except ValueError: + return False + return 0 <= netmask <= 32 + + +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 + """ + _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 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. + """ + BaseIP.__init__(self) + self._version = 6 + + # 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 + + # Assume input argument to be string or any object representation + # which converts into a formatted IP prefix string. + addr = str(ipaddr).split('/') + if len(addr) > 1: + if self._IsValidNetmask(addr[1]): + self.prefixlen = int(addr[1]) + else: + raise IPv6NetmaskValidationError(addr[1]) + else: + self.prefixlen = 128 + + self.netmask = self._IpIntFromPrefixlen(self.prefixlen) + + if not self._IsValidIp(addr[0]): + raise IPv6IpValidationError(addr[0]) + + self.ip = self._IpIntFromStr(addr[0]) + + def __repr__(self): + return '<ipaddr.IPv6: %s>' % str(self) + + @property + def ip_ext_full(self): + """Returns the expanded version of the IPv6 string.""" + return self._ExplodeShortHandIpStr(self.ip_ext) + + def SetPrefix(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._IpIntFromPrefixlen(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._IsValidNetmask(str(new_prefixlen)): + raise PrefixlenDiffInvalidError( + 'Prefix length diff %d is invalid for netblock %s' % ( + new_prefixlen, str(self))) + first = IPv6( + self._StrFromIpInt(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._StrFromIpInt(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: int - 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 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 version(self): + return self._version + + def _IsShortHandIp(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 _ExplodeShortHandIpStr(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._IsShortHandIp(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 upper 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).upper()) + return ':'.join(ret_ip) + # We've already got a longhand ip_str. + return ip_str + + def _IsValidIp(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. + """ + 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 + + # 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._ExplodeShortHandIpStr(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 _IsValidNetmask(self, prefixlen): + """Validates the netmask is in the bounds of acceptable IPv6 netmasks. + + Args: + prefixlen: A string, the netmask in prefix length format. + + Returns: + A boolean, True if the prefix length represents a valid IPv6 netmask. + """ + try: + prefixlen = int(prefixlen) + except ValueError: + return False + return 0 <= prefixlen <= 128 + + def _IpIntFromStr(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_int = 0 + + fields = self._ExplodeShortHandIpStr(ip_str).split(':') + + # Do we have an IPv4 mapped (::ffff:a.b.c.d) or compact (::a.b.c.d) address? + if fields[-1].count('.') == 3: + ipv4_string = fields.pop() + 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(octets) + + for field in fields: + ip_int = (ip_int << 16) + int(field, 16) + + return ip_int + + def _CompressHextets(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: The list of strings 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 _StrFromIpInt(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 = 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._CompressHextets(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. + """ + return self.prefixlen |