SDLC on the shoulders of giants

by pravir on Thursday, May 24, 2007

Software security veterans have all certainly thought about the idea of ‘securing the SDLC’… I can tell because every consulting firm’s collateral that I’ve seen in the past year has a new bullet under their ‘services’ section referring to something like ‘Secure development process integration’ or ‘Secure SDLC services’. That being said, let’s talk about what this means for a second. Fundamentally, there are a few ‘different’ schools of thought out there (and as it’ll turn out, they’re not all that different at all).

I know of three popular ways of looking at the problem, 1) Microsoft SDL 3.0 (with a recent book by Howard and Lipner to codify the subject), 2) Software Security Touchpoints from Gary’s book Software Security, and 3) CLASP (originally developed by Secure Software, Inc, and now an open project through OWASP). BTW, if anyone knows of other publicly usable process methodologies, by all means email me since I’d love to read about them.

After spending a bit of time thinking through all these different ideas, a few interesting points emerge. First, there’s not much difference between SDL, the Touchpoints, and CLASP. There’s just about nothing I can see where these processes fundamentally disagree. The differences are really only in the timing and the extent of the prescribed activities (i.e. they each cover the bases of what you should be doing, some just give different orderings to the activities and talk about the sub-steps in different ways). My personal opinion is that SDL is particularly suited for companies like MS (large ISVs with large user populations) and process like the Touchpoints and CLASP are a bit more flexible and widely applicable.

So what’s the deal? Do we have the problem of dev process augmentation solved and put to bed? Heck no. Consider the following quote that popped up in a discussion my buddy Gunnar Peterson and I had at the recent OWASP conference in Milan: “Amateurs talk about tactics, debutantes talk about strategy, but professionals talk about logistics.” (this quote has many variations and is hard to find a definitive source, but it’s likely from a US military officer many years ago). As the software security space was emerging, you bet we had to crawl from the primordial ooze by figuring out some tactics to stop the bleeding. Logically following, lots of smart folks sat down and figured out the right way (via experimentation, mostly) to look at the problem from a high-level. Hence, strategy for software security was born. Now, the proverbial last mile is the logistics of how you get the job done within an organization that’s got 50,000 real-world constraints that complicate everything.

Regardless of your favorite security-enhanced SDLC method, you’ll notice that they really are, at their core, a collection of activities, procedures and artifacts (tactics). Don’t get me wrong, it’s great stuff in terms of what’s needed to do the job well and it’s generally assembled and presented in a full-blown, whole-hog, flying-car way (strategy). If you’re in the shoes of the person in charge of augmenting your company’s dev processes, you’re handed a large collection of great things to think about, but little that’s directly actionable in terms of answering ‘what do I do tomorrow?’ (logistics).

What I’m getting at is that I think we’ve gotten to the point where if you’re still debating tactics of what to do or the strategic vision of what needs done for process integration, you’re solving the wrong problem. It’s about rubber-to-the-road logistics. We need to build on the work that’s been done already and come up with plans that make it accessible and usable for an average human that hasn’t made a career on thinking about these things. That’s a serious challenge, but not an impossible one. At Cigital, that’s what our SDLC process gigs are all about (providing the company a detailed plan of how to get it done). What’s needed now is to get a more abstract way of looking at the various factors that contribute to logistical differences (e.g. type of business, market vertical, organizational hierarchy, regulatory constraints, etc.). I strongly believe that we can formalize these factors and I think that goes a long way to breaking the back of the problem. I fact, I’ve been working with folks in the OWASP community on this very problem (and would love to get anyone else with field experience involved). Much of that work will be released in a new version of CLASP in the next week or so, so stay tuned if you’re interested (I’ll post another entry here announcing it).

  • http://1raindrop.typepad.com Gunnar

    I also see the logistics point as an argument for security metrics as well. There are few logistical barriers to implementing some metrics instrumentation.

  • Eric D.

    Gunnar, could you give examples of “logistical barriers for implementing some metrics instrumentation” ?

  • http://microdasys.com Robert

    Have you ever worked with SSL and XML scanning software?