Support using C_GetFunctionList() instead of library symbols.

The Python ctypes library allows us direct access to the public
symbols of a shared library, so we never bothered to implement support
for using the dispatch vector returned by C_GetFunctionList().  Well,
it turns out that there are useful debugging tools like pkcs11-spy
which require the dispatch vector support, so refactor to add it.

1 files changed, 5 insertions, 0 deletions

diff --git a/cryptech/py11/exceptions.py b/cryptech/py11/exceptions.py
index 7f86fe4..9512cda 100644
--- a/cryptech/py11/exceptions.py
+++ b/cryptech/py11/exceptions.py
@@ -28,6 +28,11 @@ class CKR_Exception(Exception):
   def __int__(self):
     return self.ckr_code
 
+  @classmethod
+  def raise_on_failure(cls, rv, func, *args):
+    if rv != CKR_OK:
+      raise cls.ckr_map[rv]
+
 CKR_OK                                                                    = 0x00000000
 
 class CKR_CANCEL        			(CKR_Exception): ckr_code = 0x00000001