[Checkins] SVN: z3c.encryptedpersistent/trunk/src/z3c/encryptedpersistent/ Use the key in the persistent object to help with the encryption.

[Stephan Richter]

Log message for revision 87824:
  Use the key in the persistent object to help with the encryption.
  

Changed:
  U   z3c.encryptedpersistent/trunk/src/z3c/encryptedpersistent/README.txt
  U   z3c.encryptedpersistent/trunk/src/z3c/encryptedpersistent/encryptedpersistent.py
  U   z3c.encryptedpersistent/trunk/src/z3c/encryptedpersistent/interfaces.py
  U   z3c.encryptedpersistent/trunk/src/z3c/encryptedpersistent/testing.py
  U   z3c.encryptedpersistent/trunk/src/z3c/encryptedpersistent/tests.py

-=-
Modified: z3c.encryptedpersistent/trunk/src/z3c/encryptedpersistent/README.txt
===================================================================
--- z3c.encryptedpersistent/trunk/src/z3c/encryptedpersistent/README.txt	2008-06-27 08:44:38 UTC (rev 87823)
+++ z3c.encryptedpersistent/trunk/src/z3c/encryptedpersistent/README.txt	2008-06-27 09:17:51 UTC (rev 87824)
@@ -13,24 +13,27 @@
   >>> myObj = MyObject()
   >>> myObj.name = u'Stephan Richter'
 
-Setup
------
 
-We need a utility that provides IEncryption for use with the 
-EncryptedPersistent object. We have defined a very simple demonstration
+The Encryption Utility
+----------------------
+
+We need a utility that provides ``IEncryption`` for use with the
+``EncryptedPersistent`` object. We have defined a very simple demonstration
 class that simply adds an "encryption string" to the data in order to indicate
 that it has encrypted it, and removes that string to decrypt the data:
 
-    >>> from zope.app.testing import ztapi
-    >>> from z3c.encryptedpersistent import testing, interfaces
-    >>> ztapi.provideUtility(interfaces.IEncryption, testing.DemoEncrypter())
-    
+    >>> import zope.component
+    >>> from z3c.encryptedpersistent import testing
+    >>> zope.component.provideUtility(testing.DemoEncrypter())
 
+
+En- and decrypting the Obejct State
+-----------------------------------
+
 When an object is stored to a database, its ``__getstate__`` method is called:
 
-
   >>> myObj.__getstate__()
-  "ENCRYPTED_(dp1\nS'name'\np2\nVStephan Richter\np3\ns."
+  (None, "ENCRYPTED_None(dp1\nS'name'\np2\nVStephan Richter\np3\ns.")
 
 When an object is loaded from the database, the state is passed into the
 ``__setstate__`` method:
@@ -42,6 +45,12 @@
   >>> myObj2.name
   u'Stephan Richter'
 
+And that's all there is to it.
+
+
+Storing in the ZODB
+-------------------
+
 Let's now test this with a full database. Since we want to test, whether the
 data is stored encrypted, we have to create a file:
 
@@ -68,5 +77,5 @@
 
 and the data is truly encrypted in the file:
 
-  >>> state in open(dbFile).read()
+  >>> state[1] in open(dbFile).read()
   True

Modified: z3c.encryptedpersistent/trunk/src/z3c/encryptedpersistent/encryptedpersistent.py
===================================================================
--- z3c.encryptedpersistent/trunk/src/z3c/encryptedpersistent/encryptedpersistent.py	2008-06-27 08:44:38 UTC (rev 87823)
+++ z3c.encryptedpersistent/trunk/src/z3c/encryptedpersistent/encryptedpersistent.py	2008-06-27 09:17:51 UTC (rev 87824)
@@ -36,12 +36,14 @@
         # 3. Convert the state to a string.
         stateStr = cPickle.dumps(state)
         # 4. Encrypt the state string and return it as the state.
-        return encryption.encrypt(stateStr)
+        return self.__key__, encryption.encrypt(self.__key__, stateStr)
 
     def __setstate__(self, encryptedState):
+        # 1. Extract the key from the state first
+        key, encryptedState = encryptedState
         # 2. Decrypt the state string.
         encryption = zope.component.getUtility(interfaces.IEncryption)
-        stateStr = encryption.decrypt(encryptedState)
+        stateStr = encryption.decrypt(key, encryptedState)
         # 3. Convert the state string to the state
         state = cPickle.loads(stateStr)
         # 4. Set the state of the object using the Persistent implementation.

Modified: z3c.encryptedpersistent/trunk/src/z3c/encryptedpersistent/interfaces.py
===================================================================
--- z3c.encryptedpersistent/trunk/src/z3c/encryptedpersistent/interfaces.py	2008-06-27 08:44:38 UTC (rev 87823)
+++ z3c.encryptedpersistent/trunk/src/z3c/encryptedpersistent/interfaces.py	2008-06-27 09:17:51 UTC (rev 87824)
@@ -15,19 +15,26 @@
 $Id$
 """
 __docformat__ = "reStructuredText"
-
 import zope.interface
 import zope.schema
 
-
 class IEncryption(zope.interface.Interface):
     """Utility providing encryption mechanism"""
 
-    def encrypt(data):
+    def encrypt(key, data):
         """Returns the encrypted data"""
 
-    def decrypt(data):
+    def decrypt(key, data):
         """Returns the decrypted data"""
 
 class IEncryptedPersistent(zope.interface.Interface):
-    """ """
\ No newline at end of file
+    """A persistent object that encrypts its state for storage."""
+
+    __key__ = zope.schema.Field(
+        title=u'Encryption Key',
+        description=(u'Encryption key/state/hint that can be used to aid '
+                     u'the encruption and decryption process. This attribute '
+                     u'can be any data structure that is necessary to '
+                     u'complete the task.'),
+        default=None,
+        required=False)

Modified: z3c.encryptedpersistent/trunk/src/z3c/encryptedpersistent/testing.py
===================================================================
--- z3c.encryptedpersistent/trunk/src/z3c/encryptedpersistent/testing.py	2008-06-27 08:44:38 UTC (rev 87823)
+++ z3c.encryptedpersistent/trunk/src/z3c/encryptedpersistent/testing.py	2008-06-27 09:17:51 UTC (rev 87824)
@@ -7,17 +7,17 @@
 $Id$
 """
 import zope.interface
+from z3c.encryptedpersistent import interfaces
 
-import interfaces
-
-
 class DemoEncrypter(object):
     zope.interface.implements(interfaces.IEncryption)
 
     _EncryptionString = "ENCRYPTED_"
 
-    def encrypt(self, data):
-        return self._EncryptionString + data
+    def encrypt(self, key, data):
+        """See interfaces.IEncryption"""
+        return self._EncryptionString + str(key) + data
 
-    def decrypt(self, data):
-        return data.lstrip(self._EncryptionString)
+    def decrypt(self, key, data):
+        """See interfaces.IEncryption"""
+        return data.lstrip(self._EncryptionString + str(key))

Modified: z3c.encryptedpersistent/trunk/src/z3c/encryptedpersistent/tests.py
===================================================================
--- z3c.encryptedpersistent/trunk/src/z3c/encryptedpersistent/tests.py	2008-06-27 08:44:38 UTC (rev 87823)
+++ z3c.encryptedpersistent/trunk/src/z3c/encryptedpersistent/tests.py	2008-06-27 09:17:51 UTC (rev 87824)
@@ -17,7 +17,7 @@
     setup.setUpTestAsModule(test, 'README')
 
 def tearDown(test):
-    tearDownTestAsModule(test)
+    setup.tearDownTestAsModule(test)
     placelesssetup.tearDown(test)
 
 def test_suite():