fix multiple object failure, plus a test to prove it.

src/django_fields/fields.py

@@ -84,9 +84,7 @@ def to_python(self, value):
             else:
                 decrypt_value = binascii.a2b_hex(value[len(self.prefix):])
             return force_unicode(
-                self.cipher.decrypt(
-                    decrypt_value
-                ).split('\0')[0]
+                self.cipher.decrypt(decrypt_value).split('\0')[0]
             )
         return value
 
@@ -102,6 +100,10 @@ def get_db_prep_value(self, value, connection=None, prepared=False):
                 value += "\0" + ''.join([random.choice(string.printable)
                     for index in range(padding-1)])
             if self.block_type:
+                self.cipher = self.cipher_object.new(
+                    settings.SECRET_KEY[:32],
+                    getattr(self.cipher_object, self.block_type),
+                    self.iv)
                 value = self.prefix + binascii.b2a_hex(self.iv + self.cipher.encrypt(value))
             else:
                 value = self.prefix + binascii.b2a_hex(self.cipher.encrypt(value))

src/django_fields/tests.py

@@ -51,7 +51,7 @@ class PickleObject(models.Model):
     data = PickleField()
 
 
-class EmailObject(models.Model): 
+class EmailObject(models.Model):
     max_email = 255
     email = EncryptedEmailField()
 
@@ -87,7 +87,7 @@ def test_encryption(self):
         encrypted_password = self._get_encrypted_password(obj.id)
         self.assertNotEqual(encrypted_password, password)
         self.assertTrue(encrypted_password.startswith('$AES$'))
-        
+
     def test_encryption_w_cipher(self):
         """
         Test that the database values are actually encrypted when using
@@ -104,6 +104,25 @@ def test_encryption_w_cipher(self):
         self.assertNotEqual(encrypted_password, password)
         self.assertTrue(encrypted_password.startswith('$AES$MODE_CBC$'))
 
+    def test_multiple_encryption_w_cipher(self):
+        """
+        Test that the database values are actually encrypted when using
+        non-default cipher types.
+        """
+        password = 'this is a password!!'  # 20 chars
+        obj = CipherEncObject(password = password)
+        obj.save()
+        # The value from the retrieved object should be the same...
+        obj = CipherEncObject.objects.get(id=obj.id)
+        self.assertEqual(password, obj.password)
+
+        password = 'another password!!'  # 20 chars
+        obj = CipherEncObject(password = password)
+        obj.save()
+        # The value from the retrieved object should be the same...
+        obj = CipherEncObject.objects.get(id=obj.id)
+        self.assertEqual(password, obj.password)
+
     def test_max_field_length(self):
         password = 'a' * EncObject.max_password
         obj = EncObject(password = password)
@@ -122,7 +141,7 @@ def test_UTF8(self):
         obj.save()
         obj = EncObject.objects.get(id=obj.id)
         self.assertEqual(password, obj.password)
-    
+
     def test_consistent_encryption(self):
         """
         The same password should not encrypt the same way twice.
@@ -134,7 +153,7 @@ def test_consistent_encryption(self):
         for pwd_length in range(1,21):  # 1-20 inclusive
             enc_pwd_1, enc_pwd_2 = self._get_two_passwords(pwd_length)
             self.assertNotEqual(enc_pwd_1, enc_pwd_2)
-    
+
     def test_minimum_padding(self):
         """
         There should always be at least two chars of padding.
@@ -163,7 +182,7 @@ def _get_encrypted_password(self, id):
         passwords = map(lambda x: x[0], cursor.fetchall())
         self.assertEqual(len(passwords), 1)  # only one
         return passwords[0]
-    
+
     def _get_encrypted_password_cipher(self, id):
         cursor = connection.cursor()
         cursor.execute("select password from django_fields_cipherencobject where id = %s", [id,])
@@ -352,7 +371,7 @@ def test_UTF8(self):
         obj.save()
         obj = EmailObject.objects.get(id=obj.id)
         self.assertEqual(email, obj.email)
-    
+
     def test_consistent_encryption(self):
         """
         The same password should not encrypt the same way twice.
@@ -364,7 +383,7 @@ def test_consistent_encryption(self):
         for email_length in range(1,21):  # 1-20 inclusive
             enc_email_1, enc_email_2 = self._get_two_emails(email_length)
             self.assertNotEqual(enc_email_1, enc_email_2)
-    
+
     def test_minimum_padding(self):
         """
         There should always be at least two chars of padding.