Skip to content

Commit

Permalink
GH-113171: Fix "private" (non-global) IP address ranges (GH-113179)
Browse files Browse the repository at this point in the history 
* GH-113171: Fix "private" (really non-global) IP address ranges

The _private_networks variables, used by various is_private
implementations, were missing some ranges and at the same time had
overly strict ranges (where there are more specific ranges considered
globally reachable by the IANA registries).

This patch updates the ranges with what was missing or otherwise
incorrect.

I left 100.64.0.0/10 alone, for now, as it's been made special in [1]
and I'm not sure if we want to undo that as I don't quite understand the
motivation behind it.

The _address_exclude_many() call returns 8 networks for IPv4, 121
networks for IPv6.

[1] #61602
  • Loading branch information
@jstasiak
jstasiak authored Mar 22, 2024
1 parent 3be9b9d commit 40d75c2
Show file tree
Hide file tree
Showing 5 changed files with 82 additions and 7 deletions.
16 changes: 16 additions & 0 deletions Doc/library/ipaddress.rst
View file
Original file line number Diff line number Diff line change
Expand Up @@ -192,6 +192,18 @@ write code that handles both IP versions correctly. Address objects are
``is_private`` has value opposite to :attr:`is_global`, except for the shared address space
(``100.64.0.0/10`` range) where they are both ``False``.

.. versionchanged:: 3.13

Fixed some false positives and false negatives.

* ``192.0.0.0/24`` is considered private with the exception of ``192.0.0.9/32`` and
``192.0.0.10/32`` (previously: only the ``192.0.0.0/29`` sub-range was considered private).
* ``64:ff9b:1::/48`` is considered private.
* ``2002::/16`` is considered private.
* There are exceptions within ``2001::/23`` (otherwise considered private): ``2001:1::1/128``,
``2001:1::2/128``, ``2001:3::/32``, ``2001:4:112::/48``, ``2001:20::/28``, ``2001:30::/28``.
The exceptions are not considered private.

.. attribute:: is_global

``True`` if the address is defined as globally reachable by
Expand All @@ -209,6 +221,10 @@ write code that handles both IP versions correctly. Address objects are

.. versionadded:: 3.4

.. versionchanged:: 3.13

Fixed some false positives and false negatives, see :attr:`is_private` for details.

.. attribute:: is_unspecified

``True`` if the address is unspecified. See :RFC:`5735` (for IPv4)
Expand Down
2 changes: 2 additions & 0 deletions Doc/whatsnew/3.13.rst
View file
Original file line number Diff line number Diff line change
Expand Up @@ -401,6 +401,8 @@ ipaddress

* Add the :attr:`ipaddress.IPv4Address.ipv6_mapped` property, which returns the IPv4-mapped IPv6 address.
(Contributed by Charles Machalow in :gh:`109466`.)
* Fix ``is_global`` and ``is_private`` behavior in ``IPv4Address``, ``IPv6Address``, ``IPv4Network``
and ``IPv6Network``.

itertools
---------
Expand Down
41 changes: 35 additions & 6 deletions Lib/ipaddress.py
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1086,7 +1086,11 @@ def is_private(self):
"""
return any(self.network_address in priv_network and
self.broadcast_address in priv_network
for priv_network in self._constants._private_networks)
for priv_network in self._constants._private_networks) and all(
self.network_address not in network and
self.broadcast_address not in network
for network in self._constants._private_networks_exceptions
)

@property
def is_global(self):
Expand Down Expand Up @@ -1347,7 +1351,10 @@ def is_private(self):
``is_private`` has value opposite to :attr:`is_global`, except for the ``100.64.0.0/10``
IPv4 range where they are both ``False``.
"""
return any(self in net for net in self._constants._private_networks)
return (
any(self in net for net in self._constants._private_networks)
and all(self not in net for net in self._constants._private_networks_exceptions)
)

@property
@functools.lru_cache()
Expand Down Expand Up @@ -1578,13 +1585,15 @@ class _IPv4Constants:

_public_network = IPv4Network('100.64.0.0/10')

# Not globally reachable address blocks listed on
# https://www.iana.org/assignments/iana-ipv4-special-registry/iana-ipv4-special-registry.xhtml
_private_networks = [
IPv4Network('0.0.0.0/8'),
IPv4Network('10.0.0.0/8'),
IPv4Network('127.0.0.0/8'),
IPv4Network('169.254.0.0/16'),
IPv4Network('172.16.0.0/12'),
IPv4Network('192.0.0.0/29'),
IPv4Network('192.0.0.0/24'),
IPv4Network('192.0.0.170/31'),
IPv4Network('192.0.2.0/24'),
IPv4Network('192.168.0.0/16'),
Expand All @@ -1595,6 +1604,11 @@ class _IPv4Constants:
IPv4Network('255.255.255.255/32'),
]

_private_networks_exceptions = [
IPv4Network('192.0.0.9/32'),
IPv4Network('192.0.0.10/32'),
]

_reserved_network = IPv4Network('240.0.0.0/4')

_unspecified_address = IPv4Address('0.0.0.0')
Expand Down Expand Up @@ -2086,7 +2100,10 @@ def is_private(self):
ipv4_mapped = self.ipv4_mapped
if ipv4_mapped is not None:
return ipv4_mapped.is_private
return any(self in net for net in self._constants._private_networks)
return (
any(self in net for net in self._constants._private_networks)
and all(self not in net for net in self._constants._private_networks_exceptions)
)

@property
def is_global(self):
Expand Down Expand Up @@ -2342,19 +2359,31 @@ class _IPv6Constants:

_multicast_network = IPv6Network('ff00::/8')

# Not globally reachable address blocks listed on
# https://www.iana.org/assignments/iana-ipv6-special-registry/iana-ipv6-special-registry.xhtml
_private_networks = [
IPv6Network('::1/128'),
IPv6Network('::/128'),
IPv6Network('::ffff:0:0/96'),
IPv6Network('64:ff9b:1::/48'),
IPv6Network('100::/64'),
IPv6Network('2001::/23'),
IPv6Network('2001:2::/48'),
IPv6Network('2001:db8::/32'),
IPv6Network('2001:10::/28'),
# IANA says N/A, let's consider it not globally reachable to be safe
IPv6Network('2002::/16'),
IPv6Network('fc00::/7'),
IPv6Network('fe80::/10'),
]

_private_networks_exceptions = [
IPv6Network('2001:1::1/128'),
IPv6Network('2001:1::2/128'),
IPv6Network('2001:3::/32'),
IPv6Network('2001:4:112::/48'),
IPv6Network('2001:20::/28'),
IPv6Network('2001:30::/28'),
]

_reserved_networks = [
IPv6Network('::/8'), IPv6Network('100::/8'),
IPv6Network('200::/7'), IPv6Network('400::/6'),
Expand Down
21 changes: 20 additions & 1 deletion Lib/test/test_ipaddress.py
View file
Original file line number Diff line number Diff line change
Expand Up @@ -2288,6 +2288,10 @@ def testReservedIpv4(self):
self.assertEqual(True, ipaddress.ip_address(
'172.31.255.255').is_private)
self.assertEqual(False, ipaddress.ip_address('172.32.0.0').is_private)
self.assertFalse(ipaddress.ip_address('192.0.0.0').is_global)
self.assertTrue(ipaddress.ip_address('192.0.0.9').is_global)
self.assertTrue(ipaddress.ip_address('192.0.0.10').is_global)
self.assertFalse(ipaddress.ip_address('192.0.0.255').is_global)

self.assertEqual(True,
ipaddress.ip_address('169.254.100.200').is_link_local)
Expand All @@ -2313,6 +2317,7 @@ def testPrivateNetworks(self):
self.assertEqual(True, ipaddress.ip_network("169.254.0.0/16").is_private)
self.assertEqual(True, ipaddress.ip_network("172.16.0.0/12").is_private)
self.assertEqual(True, ipaddress.ip_network("192.0.0.0/29").is_private)
self.assertEqual(False, ipaddress.ip_network("192.0.0.9/32").is_private)
self.assertEqual(True, ipaddress.ip_network("192.0.0.170/31").is_private)
self.assertEqual(True, ipaddress.ip_network("192.0.2.0/24").is_private)
self.assertEqual(True, ipaddress.ip_network("192.168.0.0/16").is_private)
Expand All @@ -2329,8 +2334,8 @@ def testPrivateNetworks(self):
self.assertEqual(True, ipaddress.ip_network("::/128").is_private)
self.assertEqual(True, ipaddress.ip_network("::ffff:0:0/96").is_private)
self.assertEqual(True, ipaddress.ip_network("100::/64").is_private)
self.assertEqual(True, ipaddress.ip_network("2001::/23").is_private)
self.assertEqual(True, ipaddress.ip_network("2001:2::/48").is_private)
self.assertEqual(False, ipaddress.ip_network("2001:3::/48").is_private)
self.assertEqual(True, ipaddress.ip_network("2001:db8::/32").is_private)
self.assertEqual(True, ipaddress.ip_network("2001:10::/28").is_private)
self.assertEqual(True, ipaddress.ip_network("fc00::/7").is_private)
Expand Down Expand Up @@ -2409,6 +2414,20 @@ def testReservedIpv6(self):
self.assertEqual(True, ipaddress.ip_address('0::0').is_unspecified)
self.assertEqual(False, ipaddress.ip_address('::1').is_unspecified)

self.assertFalse(ipaddress.ip_address('64:ff9b:1::').is_global)
self.assertFalse(ipaddress.ip_address('2001::').is_global)
self.assertTrue(ipaddress.ip_address('2001:1::1').is_global)
self.assertTrue(ipaddress.ip_address('2001:1::2').is_global)
self.assertFalse(ipaddress.ip_address('2001:2::').is_global)
self.assertTrue(ipaddress.ip_address('2001:3::').is_global)
self.assertFalse(ipaddress.ip_address('2001:4::').is_global)
self.assertTrue(ipaddress.ip_address('2001:4:112::').is_global)
self.assertFalse(ipaddress.ip_address('2001:10::').is_global)
self.assertTrue(ipaddress.ip_address('2001:20::').is_global)
self.assertTrue(ipaddress.ip_address('2001:30::').is_global)
self.assertFalse(ipaddress.ip_address('2001:40::').is_global)
self.assertFalse(ipaddress.ip_address('2002::').is_global)

# some generic IETF reserved addresses
self.assertEqual(True, ipaddress.ip_address('100::').is_reserved)
self.assertEqual(True, ipaddress.ip_network('4000::1/128').is_reserved)
Expand Down
9 changes: 9 additions & 0 deletions Misc/NEWS.d/next/Library/2024-03-14-01-38-44.gh-issue-113171.VFnObz.rst
View file
Original file line number Diff line number Diff line change
@@ -0,0 +1,9 @@
Fixed various false positives and false negatives in

* :attr:`ipaddress.IPv4Address.is_private` (see these docs for details)
* :attr:`ipaddress.IPv4Address.is_global`
* :attr:`ipaddress.IPv6Address.is_private`
* :attr:`ipaddress.IPv6Address.is_global`

Also in the corresponding :class:`ipaddress.IPv4Network` and :class:`ipaddress.IPv6Network`
attributes.

0 comments on commit 40d75c2

Please sign in to comment.