Bug#355947: python-pyopenssl: Segmentation fault when creating x509 extension

[Zsolt Cserna]

Package: python-pyopenssl
Version: 0.6-2
Severity: grave
Tags: patch
Justification: renders package unusable

When I want to create x509 extensions, I get segmentation fault.
The python code which do this is the following:

from OpenSSL import crypto
crypto.X509Extension("basicConstraints", True, "CA:TRUE")

There is a patch on this URL:
http://sourceforge.net/tracker/index.php?func=detail&aid=1166109&group_id=31249&atid=401760
I attached the patch to this email.

This patch is _not_ made by me. I applied this patch to the original package
and it seems to work fine.


-- System Information:
Debian Release: 3.1
  APT prefers testing
  APT policy: (500, 'testing')
Architecture: i386 (i686)
Kernel: Linux 2.4.30
Locale: LANG=C, LC_CTYPE=hu_HU (charmap=ISO-8859-2)

Versions of packages python-pyopenssl depends on:
ii  python                        2.3.5-2    An interactive high-level object-o
ii  python2.3-pyopenssl           0.6-2      Python wrapper around the OpenSSL 

-- no debconf information

diff -Naur pyOpenSSL-0.6.orig/src/crypto/x509ext.c pyOpenSSL-0.6/src/crypto/x509ext.c
--- pyOpenSSL-0.6.orig/src/crypto/x509ext.c	2002-07-09 15:34:46.000000000 +0200
+++ pyOpenSSL-0.6/src/crypto/x509ext.c	2005-03-14 17:25:42.000000000 +0100
@@ -57,7 +57,7 @@
 {
     crypto_X509ExtensionObj *self;
     int ext_len, ext_nid;
-    unsigned char *ext_der, *p;
+    unsigned char *ext_der;
     X509V3_EXT_METHOD *ext_method = NULL;
     ASN1_OCTET_STRING *ext_oct;
     STACK_OF(CONF_VALUE) *nval;
@@ -110,17 +110,29 @@
     sk_CONF_VALUE_pop_free(nval, X509V3_conf_free);
         
     /* Find out how much memory we need */
-    ext_len = ext_method->i2d(ext_struct, NULL);
-                
-    /* Allocate */
-    if(!(ext_der = malloc(ext_len))) {
-        PyErr_SetString(PyExc_MemoryError, "Could not allocate memory");
-        return NULL;
+
+
+    /* Convert internal representation to DER */
+    /* and Allocate */
+    if (ext_method->it) {
+        ext_der = NULL;
+        ext_len = ASN1_item_i2d(ext_struct, &ext_der, ASN1_ITEM_ptr(ext_method->it));
+        if (ext_len < 0) {
+            PyErr_SetString(PyExc_MemoryError, "Could not allocate memory");
+            return NULL;
+        }
+    } else {
+        unsigned char *p;
+        ext_len = ext_method->i2d(ext_struct, NULL);
+        if(!(ext_der = malloc(ext_len))) {
+            PyErr_SetString(PyExc_MemoryError, "Could not allocate memory");
+            return NULL;
+        }
+        p = ext_der;
+        ext_method->i2d(ext_struct, &p);
     }
 
     /* And create the ASN1_OCTET_STRING */
-    p = ext_der;
-    ext_method->i2d(ext_struct, &p);
     if(!(ext_oct = M_ASN1_OCTET_STRING_new())) {
         exception_from_error_queue();
         return NULL;
@@ -140,7 +152,7 @@
     }
     
     M_ASN1_OCTET_STRING_free(ext_oct);
-    ext_method->ext_free(ext_struct);
+    //ext_method->ext_free(ext_struct);
 
     self->x509_extension = extension;
     self->dealloc = 1;