I'm not sure which of the three definitions in Brian's message you're not concurring with, but I think he was only listing them as strawmen anyway.
In any case, there's no reason that static analysis tools shouldn't be able to find errors of omission. We use our tools to find these 'dogs that didn't bark' every day. The tools can identify, for example, places where logging, input validation, and error handling should have been done. With a little work teaching the tool about your application, assets, and libraries, it's easy to find places where encryption, access control, and authentication should have been done but haven't. In your hypothetical, if the API isn't ever invoked with an identity and a secret, there can't be authentication. If there's no call to an access control component, we know at least that there's no centralized mechanism. In this case, the tool could check whether the code follows the project's standard access control pattern. If not, it's an error of omission. If I remember correctly, Saltzer and Schroeder only suggested 8 principles. Your hypo is closest to complete mediation, but touches on several others. But, in theory, there's no reason that static analysis can't help verify all of them in an application. --Jeff -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Gary McGraw Sent: Monday, February 06, 2006 11:13 PM To: Brian Chess; sc-l@securecoding.org Subject: RE: [SC-L] Bugs and flaws Hi all, I'm afraid I don't concur with this definition. Here's a (rather vague) flaw example that may help clarify what I mean. Think about an error of omission where an API is exposed with no A&A protection whatsoever. This API may have been designed not to have been exposed originally, but somehow became exposed only over time. How do you find errors of omission with a static analysis tool? This is only one of salzer and schroeder's principles in action. What of the other 9? gem P.s. Five points to whoever names the principle in question. P.p.s. The book is out www.swsec.com -----Original Message----- From: Brian Chess [mailto:[EMAIL PROTECTED] Sent: Sat Feb 04 00:56:16 2006 To: sc-l@securecoding.org Subject: RE: [SC-L] Bugs and flaws The best definition for "flaw" and "bug" I've heard so far is that a flaw is a successful implementation of your intent, while a bug is unintentional. I think I've also heard "a bug is small", a flaw is big", but that definition is awfully squishy. If the difference between a bug and a flaw is indeed one of intent, then I don't think it's a useful distinction. Intent rarely brings with it other dependable characteristics. I've also heard "bugs are things that a static analysis tool can find", but I don't think that really captures it either. For example, it's easy for a static analysis tool to point out that the following Java statement implies that the program is using weak cryptography: SecretKey key = KeyGenerator.getInstance("DES").generateKey(); Brian _______________________________________________ Secure Coding mailing list (SC-L) SC-L@securecoding.org List information, subscriptions, etc - http://krvw.com/mailman/listinfo/sc-l List charter available at - http://www.securecoding.org/list/charter.php ---------------------------------------------------------------------------- This electronic message transmission contains information that may be confidential or privileged. The information contained herein is intended solely for the recipient and use by any other party is not authorized. If you are not the intended recipient (or otherwise authorized to receive this message by the intended recipient), any disclosure, copying, distribution or use of the contents of the information is prohibited. If you have received this electronic message transmission in error, please contact the sender by reply email and delete all copies of this message. Cigital, Inc. accepts no responsibility for any loss or damage resulting directly or indirectly from the use of this email or its contents. Thank You. ---------------------------------------------------------------------------- _______________________________________________ Secure Coding mailing list (SC-L) SC-L@securecoding.org List information, subscriptions, etc - http://krvw.com/mailman/listinfo/sc-l List charter available at - http://www.securecoding.org/list/charter.php _______________________________________________ Secure Coding mailing list (SC-L) SC-L@securecoding.org List information, subscriptions, etc - http://krvw.com/mailman/listinfo/sc-l List charter available at - http://www.securecoding.org/list/charter.php
