Issue #13885: CVE-2011-3389: the _ssl module would always disable the CBC IV attack countermeasure.

pitrou · pitrou · commit f2bf8a6ac515 · 2012-01-27T09:48:47.000+01:00
diff --git a/Misc/NEWS b/Misc/NEWS
@@ -13,6 +13,9 @@ Core and Builtins
 Library
 -------
 
+- Issue #13885: CVE-2011-3389: the _ssl module would always disable the CBC
+  IV attack countermeasure.
+
 - Issue #11603: Fix a crash when __str__ is rebound as __repr__.  Patch by
   Andreas Stührk.
 
diff --git a/Modules/_ssl.c b/Modules/_ssl.c
@@ -365,7 +365,8 @@ newPySSLObject(PySocketSockObject *Sock, char *key_file, char *cert_file,
     }
 
     /* ssl compatibility */
-    SSL_CTX_set_options(self->ctx, SSL_OP_ALL);
+    SSL_CTX_set_options(self->ctx,
+                        SSL_OP_ALL & ~SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS);
 
     verification_mode = SSL_VERIFY_NONE;
     if (certreq == PY_SSL_CERT_OPTIONAL)

Original file line number	Diff line number	Diff line change
`@@ -365,7 +365,8 @@ newPySSLObject(PySocketSockObject Sock, char key_file, char *cert_file,`
`365`	`365`	`}`
`366`	`366`
`367`	`367`	`/* ssl compatibility */`
`368`		`- SSL_CTX_set_options(self->ctx, SSL_OP_ALL);`
	`368`	`+ SSL_CTX_set_options(self->ctx,`
	`369`	`+ SSL_OP_ALL & ~SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS);`
`369`	`370`
`370`	`371`	`verification_mode = SSL_VERIFY_NONE;`
`371`	`372`	`if (certreq == PY_SSL_CERT_OPTIONAL)`