aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorMiss Islington (bot) <31488909+miss-islington@users.noreply.github.com>2020-06-29 11:12:50 -0700
committerGitHub <noreply@github.com>2020-06-29 11:12:50 -0700
commitdc8ce8ead182de46584cc1ed8a8c51d48240cbd5 (patch)
tree1db73719f1165dddb6c97a759fdd45bb3f776e49
parentbpo-41048: mimetypes should read the rule file using UTF-8, not the locale en... (diff)
downloadcpython-dc8ce8ead182de46584cc1ed8a8c51d48240cbd5.tar.gz
cpython-dc8ce8ead182de46584cc1ed8a8c51d48240cbd5.tar.bz2
cpython-dc8ce8ead182de46584cc1ed8a8c51d48240cbd5.zip
bpo-41004: Resolve hash collisions for IPv4Interface and IPv6Interface (GH-21033)
The __hash__() methods of classes IPv4Interface and IPv6Interface had issue of generating constant hash values of 32 and 128 respectively causing hash collisions. The fix uses the hash() function to generate hash values for the objects instead of XOR operation (cherry picked from commit b30ee26e366bf509b7538d79bfec6c6d38d53f28) Co-authored-by: Ravi Teja P <rvteja92@gmail.com>
-rw-r--r--Lib/ipaddress.py4
-rw-r--r--Lib/test/test_ipaddress.py12
-rw-r--r--Misc/NEWS.d/next/Security/2020-06-29-16-02-29.bpo-41004.ovF0KZ.rst1
3 files changed, 15 insertions, 2 deletions
diff --git a/Lib/ipaddress.py b/Lib/ipaddress.py
index 873c7644081..a3a04f7f4b3 100644
--- a/Lib/ipaddress.py
+++ b/Lib/ipaddress.py
@@ -1370,7 +1370,7 @@ class IPv4Interface(IPv4Address):
return False
def __hash__(self):
- return self._ip ^ self._prefixlen ^ int(self.network.network_address)
+ return hash((self._ip, self._prefixlen, int(self.network.network_address)))
__reduce__ = _IPAddressBase.__reduce__
@@ -2017,7 +2017,7 @@ class IPv6Interface(IPv6Address):
return False
def __hash__(self):
- return self._ip ^ self._prefixlen ^ int(self.network.network_address)
+ return hash((self._ip, self._prefixlen, int(self.network.network_address)))
__reduce__ = _IPAddressBase.__reduce__
diff --git a/Lib/test/test_ipaddress.py b/Lib/test/test_ipaddress.py
index de77111705b..2eba740e5e7 100644
--- a/Lib/test/test_ipaddress.py
+++ b/Lib/test/test_ipaddress.py
@@ -2053,6 +2053,18 @@ class IpaddrUnitTest(unittest.TestCase):
sixtofouraddr.sixtofour)
self.assertFalse(bad_addr.sixtofour)
+ # issue41004 Hash collisions in IPv4Interface and IPv6Interface
+ def testV4HashIsNotConstant(self):
+ ipv4_address1 = ipaddress.IPv4Interface("1.2.3.4")
+ ipv4_address2 = ipaddress.IPv4Interface("2.3.4.5")
+ self.assertNotEqual(ipv4_address1.__hash__(), ipv4_address2.__hash__())
+
+ # issue41004 Hash collisions in IPv4Interface and IPv6Interface
+ def testV6HashIsNotConstant(self):
+ ipv6_address1 = ipaddress.IPv6Interface("2001:658:22a:cafe:200:0:0:1")
+ ipv6_address2 = ipaddress.IPv6Interface("2001:658:22a:cafe:200:0:0:2")
+ self.assertNotEqual(ipv6_address1.__hash__(), ipv6_address2.__hash__())
+
if __name__ == '__main__':
unittest.main()
diff --git a/Misc/NEWS.d/next/Security/2020-06-29-16-02-29.bpo-41004.ovF0KZ.rst b/Misc/NEWS.d/next/Security/2020-06-29-16-02-29.bpo-41004.ovF0KZ.rst
new file mode 100644
index 00000000000..1380b31fbe9
--- /dev/null
+++ b/Misc/NEWS.d/next/Security/2020-06-29-16-02-29.bpo-41004.ovF0KZ.rst
@@ -0,0 +1 @@
+The __hash__() methods of ipaddress.IPv4Interface and ipaddress.IPv6Interface incorrectly generated constant hash values of 32 and 128 respectively. This resulted in always causing hash collisions. The fix uses hash() to generate hash values for the tuple of (address, mask length, network address).