Changeset 52

Timestamp:

07/09/13 11:17:19 (11 years ago)

Author:

tmorgan

Message:

fixed an off-by-one

Location:

trunk

Files:

• doc/TODO (modified) (1 diff)
• lib/bletchley/CBC/__init__.py (modified) (4 diffs)

trunk/doc/TODO

@@ -12 +12 @@
 Future
 ======
+
+* Generalize CBC-R methods to support any block decryption oracle
+  http://blog.spiderlabs.com/2013/06/cbc-r-its-not-just-for-padding-oracles.html
 
 * Codetective

trunk/lib/bletchley/CBC/__init__.py

@@ -3 +3 @@
 
 Copyright (C) 2010 ELOI SANFÈLIX
-Copyright (C) 2012 Timothy D. Morgan
+Copyright (C) 2012-2013 Timothy D. Morgan
 @author: Eloi Sanfelix < eloi AT limited-entropy.com >
 @author: Timothy D. Morgan < tmorgan {a} vsecurity . com >
@@ -223 +223 @@
         suffix = struct.pack("B"*len(suffix),*suffix)+block
 
-
+        # XXX: catch any signal exceptions, such as ^C, and communicate
+        #      this back to the rest of the script so it can end immediately 
         for x in range(0, 1+self.retries):
             # Each thread spawned searches a subset of the next byte's 
@@ -284 +285 @@
             if pad_bytes == None:
                 # XXX: custom exception
+                self.log_message("Could not determine pad length")
                 raise Exception
             
@@ -314 +316 @@
                 
         # Finally decrypt first block
-        decrypted = self.decrypt_block(self._iv, blocks[0], partial) + decrypted
+        if finished_blocks < len(blocks):
+            decrypted = self.decrypt_block(self._iv, blocks[0], partial) + decrypted
         
         # Remove the padding and return