Issue #18709: Fix CVE-2013-4238. The SSL module now handles NULL bytes

inside subjectAltName correctly. Formerly the module has used OpenSSL's
GENERAL_NAME_print() function to get the string represention of ASN.1
strings for rfc822Name (email), dNSName (DNS) and
uniformResourceIdentifier (URI).

1 files changed, 90 insertions, 0 deletions

diff --git a/Lib/test/nullbytecert.pem b/Lib/test/nullbytecert.pem
new file mode 100644
index 0000000..447186c
--- /dev/null
+++ b/Lib/test/nullbytecert.pem
@@ -0,0 +1,90 @@
+Certificate:
+    Data:
+        Version: 3 (0x2)
+        Serial Number: 0 (0x0)
+    Signature Algorithm: sha1WithRSAEncryption
+        Issuer: C=US, ST=Oregon, L=Beaverton, O=Python Software Foundation, OU=Python Core Development, CN=null.python.org\x00example.org/emailAddress=python-dev@python.org
+        Validity
+            Not Before: Aug  7 13:11:52 2013 GMT
+            Not After : Aug  7 13:12:52 2013 GMT
+        Subject: C=US, ST=Oregon, L=Beaverton, O=Python Software Foundation, OU=Python Core Development, CN=null.python.org\x00example.org/emailAddress=python-dev@python.org
+        Subject Public Key Info:
+            Public Key Algorithm: rsaEncryption
+                Public-Key: (2048 bit)
+                Modulus:
+                    00:b5:ea:ed:c9:fb:46:7d:6f:3b:76:80:dd:3a:f3:
+                    03:94:0b:a7:a6:db:ec:1d:df:ff:23:74:08:9d:97:
+                    16:3f:a3:a4:7b:3e:1b:0e:96:59:25:03:a7:26:e2:
+                    88:a9:cf:79:cd:f7:04:56:b0:ab:79:32:6e:59:c1:
+                    32:30:54:eb:58:a8:cb:91:f0:42:a5:64:27:cb:d4:
+                    56:31:88:52:ad:cf:bd:7f:f0:06:64:1f:cc:27:b8:
+                    a3:8b:8c:f3:d8:29:1f:25:0b:f5:46:06:1b:ca:02:
+                    45:ad:7b:76:0a:9c:bf:bb:b9:ae:0d:16:ab:60:75:
+                    ae:06:3e:9c:7c:31:dc:92:2f:29:1a:e0:4b:0c:91:
+                    90:6c:e9:37:c5:90:d7:2a:d7:97:15:a3:80:8f:5d:
+                    7b:49:8f:54:30:d4:97:2c:1c:5b:37:b5:ab:69:30:
+                    68:43:d3:33:78:4b:02:60:f5:3c:44:80:a1:8f:e7:
+                    f0:0f:d1:5e:87:9e:46:cf:62:fc:f9:bf:0c:65:12:
+                    f1:93:c8:35:79:3f:c8:ec:ec:47:f5:ef:be:44:d5:
+                    ae:82:1e:2d:9a:9f:98:5a:67:65:e1:74:70:7c:cb:
+                    d3:c2:ce:0e:45:49:27:dc:e3:2d:d4:fb:48:0e:2f:
+                    9e:77:b8:14:46:c0:c4:36:ca:02:ae:6a:91:8c:da:
+                    2f:85
+                Exponent: 65537 (0x10001)
+        X509v3 extensions:
+            X509v3 Basic Constraints: critical
+                CA:FALSE
+            X509v3 Subject Key Identifier:
+                88:5A:55:C0:52:FF:61:CD:52:A3:35:0F:EA:5A:9C:24:38:22:F7:5C
+            X509v3 Key Usage:
+                Digital Signature, Non Repudiation, Key Encipherment
+            X509v3 Subject Alternative Name:
+                *************************************************************
+                WARNING: The values for DNS, email and URI are WRONG. OpenSSL
+                         doesn't print the text after a NULL byte.
+                *************************************************************
+                DNS:altnull.python.org, email:null@python.org, URI:http://null.python.org, IP Address:192.0.2.1, IP Address:2001:DB8:0:0:0:0:0:1
+    Signature Algorithm: sha1WithRSAEncryption
+         ac:4f:45:ef:7d:49:a8:21:70:8e:88:59:3e:d4:36:42:70:f5:
+         a3:bd:8b:d7:a8:d0:58:f6:31:4a:b1:a4:a6:dd:6f:d9:e8:44:
+         3c:b6:0a:71:d6:7f:b1:08:61:9d:60:ce:75:cf:77:0c:d2:37:
+         86:02:8d:5e:5d:f9:0f:71:b4:16:a8:c1:3d:23:1c:f1:11:b3:
+         56:6e:ca:d0:8d:34:94:e6:87:2a:99:f2:ae:ae:cc:c2:e8:86:
+         de:08:a8:7f:c5:05:fa:6f:81:a7:82:e6:d0:53:9d:34:f4:ac:
+         3e:40:fe:89:57:7a:29:a4:91:7e:0b:c6:51:31:e5:10:2f:a4:
+         60:76:cd:95:51:1a:be:8b:a1:b0:fd:ad:52:bd:d7:1b:87:60:
+         d2:31:c7:17:c4:18:4f:2d:08:25:a3:a7:4f:b7:92:ca:e2:f5:
+         25:f1:54:75:81:9d:b3:3d:61:a2:f7:da:ed:e1:c6:6f:2c:60:
+         1f:d8:6f:c5:92:05:ab:c9:09:62:49:a9:14:ad:55:11:cc:d6:
+         4a:19:94:99:97:37:1d:81:5f:8b:cf:a3:a8:96:44:51:08:3d:
+         0b:05:65:12:eb:b6:70:80:88:48:72:4f:c6:c2:da:cf:cd:8e:
+         5b:ba:97:2f:60:b4:96:56:49:5e:3a:43:76:63:04:be:2a:f6:
+         c1:ca:a9:94
+-----BEGIN CERTIFICATE-----
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+vX/wBmQfzCe4o4uM89gpHyUL9UYGG8oCRa17dgqcv7u5rg0Wq2B1rgY+nHwx3JIv
+KRrgSwyRkGzpN8WQ1yrXlxWjgI9de0mPVDDUlywcWze1q2kwaEPTM3hLAmD1PESA
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+bGwucHl0aG9uLm9yZwBodHRwOi8vZXhhbXBsZS5vcmeHBMAAAgGHECABDbgAAAAA
+AAAAAAAAAAEwDQYJKoZIhvcNAQEFBQADggEBAKxPRe99SaghcI6IWT7UNkJw9aO9
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+RFEIPQsFZRLrtnCAiEhyT8bC2s/Njlu6ly9gtJZWSV46Q3ZjBL4q9sHKqZQ=
+-----END CERTIFICATE-----