Added check to turn of CC backend for OS X version < 10.8

1 files changed, 13 insertions, 1 deletions

diff --git a/cryptography/hazmat/bindings/commoncrypto/binding.py b/cryptography/hazmat/bindings/commoncrypto/binding.py
index 45c0eaad..07d9cc6d 100644
--- a/cryptography/hazmat/bindings/commoncrypto/binding.py
+++ b/cryptography/hazmat/bindings/commoncrypto/binding.py
@@ -14,6 +14,9 @@
 from __future__ import absolute_import, division, print_function
 
 import sys
+import platform
+
+from pkg_resources import parse_version
 
 from cryptography.hazmat.bindings.utils import build_ffi
 
@@ -46,4 +49,13 @@ class Binding(object):
 
     @classmethod
     def is_available(cls):
-        return sys.platform == "darwin"
+        if sys.platform == "darwin":
+            version = parse_version(platform.mac_ver()[0])
+            if version < parse_version("10.8"):
+                return False
+
+            else:
+                return True
+
+        else:
+            return False