From 05a14677846ed0a35773cd2ba582f9a65a3dfa48 Mon Sep 17 00:00:00 2001 From: Petr Viktorin Date: Wed, 24 Apr 2024 14:29:30 +0200 Subject: [PATCH] gh-113171: gh-65056: Fix "private" (non-global) IP address ranges (GH-113179) (GH-113186) (GH-118177) * GH-113171: Fix "private" (non-global) IP address ranges (GH-113179) 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. 100.64.0.0/10 is left alone, for now, as it's been made special in [1]. The _address_exclude_many() call returns 8 networks for IPv4, 121 networks for IPv6. [1] https://github.com/python/cpython/issues/61602 * GH-65056: Improve the IP address' is_global/is_private documentation (GH-113186) It wasn't clear what the semantics of is_global/is_private are and, when one gets to the bottom of it, it's not quite so simple (hence the exceptions listed). (cherry picked from commit 2a4cbf17af19a01d942f9579342f77c39fbd23c4) (cherry picked from commit 40d75c2b7f5c67e254d0a025e0f2e2c7ada7f69f) --------- (cherry picked from commit f86b17ac511e68192ba71f27e752321a3252cee3) Co-authored-by: Jakub Stasiak --- Doc/library/ipaddress.rst | 43 ++++++++- Doc/whatsnew/3.8.rst | 9 ++ Lib/ipaddress.py | 95 +++++++++++++++---- Lib/test/test_ipaddress.py | 52 ++++++++++ ...-03-14-01-38-44.gh-issue-113171.VFnObz.rst | 9 ++ 5 files changed, 187 insertions(+), 21 deletions(-) create mode 100644 Misc/NEWS.d/next/Library/2024-03-14-01-38-44.gh-issue-113171.VFnObz.rst diff --git a/Doc/library/ipaddress.rst b/Doc/library/ipaddress.rst index 5e21d5db2ed9c3..5944e33bb1b339 100644 --- a/Doc/library/ipaddress.rst +++ b/Doc/library/ipaddress.rst @@ -179,18 +179,53 @@ write code that handles both IP versions correctly. Address objects are .. attribute:: is_private - ``True`` if the address is allocated for private networks. See + ``True`` if the address is defined as not globally reachable by iana-ipv4-special-registry_ (for IPv4) or iana-ipv6-special-registry_ - (for IPv6). + (for IPv6) with the following exceptions: + + * ``is_private`` is ``False`` for the shared address space (``100.64.0.0/10``) + * For IPv4-mapped IPv6-addresses the ``is_private`` value is determined by the + semantics of the underlying IPv4 addresses and the following condition holds + (see :attr:`IPv6Address.ipv4_mapped`):: + + address.is_private == address.ipv4_mapped.is_private + + ``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:: 3.8.20 + + 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 allocated for public networks. See + ``True`` if the address is defined as globally reachable by iana-ipv4-special-registry_ (for IPv4) or iana-ipv6-special-registry_ - (for IPv6). + (for IPv6) with the following exception: + + For IPv4-mapped IPv6-addresses the ``is_private`` value is determined by the + semantics of the underlying IPv4 addresses and the following condition holds + (see :attr:`IPv6Address.ipv4_mapped`):: + + address.is_global == address.ipv4_mapped.is_global + + ``is_global`` has value opposite to :attr:`is_private`, except for the shared address space + (``100.64.0.0/10`` range) where they are both ``False``. .. versionadded:: 3.4 + .. versionchanged:: 3.8.20 + + 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) diff --git a/Doc/whatsnew/3.8.rst b/Doc/whatsnew/3.8.rst index e5278da3f6a5be..de4dd856877543 100644 --- a/Doc/whatsnew/3.8.rst +++ b/Doc/whatsnew/3.8.rst @@ -2355,3 +2355,12 @@ tarfile :exc:`DeprecationWarning`. In Python 3.14, the default will switch to ``'data'``. (Contributed by Petr Viktorin in :pep:`706`.) + +Notable changes in 3.8.20 +========================= + +ipaddress +--------- + +* Fixed ``is_global`` and ``is_private`` behavior in ``IPv4Address``, + ``IPv6Address``, ``IPv4Network`` and ``IPv6Network``. diff --git a/Lib/ipaddress.py b/Lib/ipaddress.py index d351f07a5bd960..142c3b13b1617e 100644 --- a/Lib/ipaddress.py +++ b/Lib/ipaddress.py @@ -1275,18 +1275,41 @@ def is_reserved(self): @property @functools.lru_cache() def is_private(self): - """Test if this address is allocated for private networks. + """``True`` if the address is defined as not globally reachable by + iana-ipv4-special-registry_ (for IPv4) or iana-ipv6-special-registry_ + (for IPv6) with the following exceptions: - Returns: - A boolean, True if the address is reserved per - iana-ipv4-special-registry. + * ``is_private`` is ``False`` for ``100.64.0.0/10`` + * For IPv4-mapped IPv6-addresses the ``is_private`` value is determined by the + semantics of the underlying IPv4 addresses and the following condition holds + (see :attr:`IPv6Address.ipv4_mapped`):: + + address.is_private == address.ipv4_mapped.is_private + ``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() def is_global(self): + """``True`` if the address is defined as globally reachable by + iana-ipv4-special-registry_ (for IPv4) or iana-ipv6-special-registry_ + (for IPv6) with the following exception: + + For IPv4-mapped IPv6-addresses the ``is_private`` value is determined by the + semantics of the underlying IPv4 addresses and the following condition holds + (see :attr:`IPv6Address.ipv4_mapped`):: + + address.is_global == address.ipv4_mapped.is_global + + ``is_global`` has value opposite to :attr:`is_private`, except for the ``100.64.0.0/10`` + IPv4 range where they are both ``False``. + """ return self not in self._constants._public_network and not self.is_private @property @@ -1490,13 +1513,15 @@ 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'), @@ -1507,6 +1532,11 @@ 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') @@ -1897,23 +1927,42 @@ def is_site_local(self): @property @functools.lru_cache() def is_private(self): - """Test if this address is allocated for private networks. + """``True`` if the address is defined as not globally reachable by + iana-ipv4-special-registry_ (for IPv4) or iana-ipv6-special-registry_ + (for IPv6) with the following exceptions: - Returns: - A boolean, True if the address is reserved per - iana-ipv6-special-registry. + * ``is_private`` is ``False`` for ``100.64.0.0/10`` + * For IPv4-mapped IPv6-addresses the ``is_private`` value is determined by the + semantics of the underlying IPv4 addresses and the following condition holds + (see :attr:`IPv6Address.ipv4_mapped`):: + + address.is_private == address.ipv4_mapped.is_private + ``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) + 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) + and all(self not in net for net in self._constants._private_networks_exceptions) + ) @property def is_global(self): - """Test if this address is allocated for public networks. + """``True`` if the address is defined as globally reachable by + iana-ipv4-special-registry_ (for IPv4) or iana-ipv6-special-registry_ + (for IPv6) with the following exception: - Returns: - A boolean, true if the address is not reserved per - iana-ipv6-special-registry. + For IPv4-mapped IPv6-addresses the ``is_private`` value is determined by the + semantics of the underlying IPv4 addresses and the following condition holds + (see :attr:`IPv6Address.ipv4_mapped`):: + + address.is_global == address.ipv4_mapped.is_global + ``is_global`` has value opposite to :attr:`is_private`, except for the ``100.64.0.0/10`` + IPv4 range where they are both ``False``. """ return not self.is_private @@ -2154,19 +2203,31 @@ 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'), diff --git a/Lib/test/test_ipaddress.py b/Lib/test/test_ipaddress.py index 1297b8371d8583..46002111b3270a 100644 --- a/Lib/test/test_ipaddress.py +++ b/Lib/test/test_ipaddress.py @@ -1761,6 +1761,10 @@ 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) @@ -1776,6 +1780,40 @@ def testReservedIpv4(self): self.assertEqual(False, ipaddress.ip_address('128.0.0.0').is_loopback) self.assertEqual(True, ipaddress.ip_network('0.0.0.0').is_unspecified) + def testPrivateNetworks(self): + self.assertEqual(False, ipaddress.ip_network("0.0.0.0/0").is_private) + self.assertEqual(False, ipaddress.ip_network("1.0.0.0/8").is_private) + + self.assertEqual(True, ipaddress.ip_network("0.0.0.0/8").is_private) + self.assertEqual(True, ipaddress.ip_network("10.0.0.0/8").is_private) + self.assertEqual(True, ipaddress.ip_network("127.0.0.0/8").is_private) + 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) + self.assertEqual(True, ipaddress.ip_network("198.18.0.0/15").is_private) + self.assertEqual(True, ipaddress.ip_network("198.51.100.0/24").is_private) + self.assertEqual(True, ipaddress.ip_network("203.0.113.0/24").is_private) + self.assertEqual(True, ipaddress.ip_network("240.0.0.0/4").is_private) + self.assertEqual(True, ipaddress.ip_network("255.255.255.255/32").is_private) + + self.assertEqual(False, ipaddress.ip_network("::/0").is_private) + self.assertEqual(False, ipaddress.ip_network("::ff/128").is_private) + + self.assertEqual(True, ipaddress.ip_network("::1/128").is_private) + 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("2001:2::/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) + self.assertEqual(True, ipaddress.ip_network("fe80::/10").is_private) + def testReservedIpv6(self): self.assertEqual(True, ipaddress.ip_network('ffff::').is_multicast) @@ -1849,6 +1887,20 @@ 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) diff --git a/Misc/NEWS.d/next/Library/2024-03-14-01-38-44.gh-issue-113171.VFnObz.rst b/Misc/NEWS.d/next/Library/2024-03-14-01-38-44.gh-issue-113171.VFnObz.rst new file mode 100644 index 00000000000000..f9a72473be4e2c --- /dev/null +++ b/Misc/NEWS.d/next/Library/2024-03-14-01-38-44.gh-issue-113171.VFnObz.rst @@ -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.