Sean, I think you would want to provide this guarantee through some sort of static assertion. For example, if you want to ensure that text controlled by FRED is not included in a release build, you could include an #error preprocessor directive as part of the controlled text that will generate an error message for a release build:
#ifdef FRED # define MACRO(x) (x + 5) # ifdef NDEBUG # error "FRED defined in release build" # endif #endif The idea here is that NDEBUG would be defined for a release build. If FRED and NDEBUG were defined in the same build it would result in a fatal compile-time diagnostic. I'm not sure if there is a more elegant or widely deployed solution to this problem. rCs -----Original Message----- From: sc-l-boun...@securecoding.org [mailto:sc-l-boun...@securecoding.org] On Behalf Of smurray1 Sent: Friday, February 13, 2009 10:49 AM To: sc-l@securecoding.org Subject: [SC-L] Conditional Compile statements-- coding standards, and code review I am reviewing a QA team's procedures for code review. I have an issue with conditional compile statements (#ifdef in the C world). My issue is that it is very difficult to have complete confidence that a piece of code inside the condition (the "controlled text") does indeed not get compiled and included in the final executable. The coding standards used by the organization are fairly rigorous, but there is no mention of prohibiting (or of even limiting) the used of conditional compile statements. They are typically used for debug purposes-- that is, debug messages that get generated when the code is compiled for debugging and then are omitted in the production builds. This is probably more of a correct code issue than a security issue, but there are most definitely security implications. I am curious to hear people's thoughts on this. Do most organizations prohibit (or at least limit) conditional compile statements? If not, how is the "controlled text" inside conditional compile statements handled by code reviewers? The QA procedures I am reviewing basically ignore them, since "They won't be in the production build", but I am very uncomfortable with that. There are many ways in C to define the macro that controls the conditional compile (with #define statements, with compiler flags, etc). It just seems very hard to verify that the ifdefs will work as planned in the final compile. Thanks!! Sean T Murray _______________________________________________ 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 SC-L is hosted and moderated by KRvW Associates, LLC (http://www.KRvW.com) as a free, non-commercial service to the software security community. _______________________________________________ _______________________________________________ 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 SC-L is hosted and moderated by KRvW Associates, LLC (http://www.KRvW.com) as a free, non-commercial service to the software security community. _______________________________________________
