The ideas of DevOps are a mixture of principles, ideas, recommendations, tools, processes, attitudes, and more. There isn’t any one way to implement a DevOps process, and plenty of people have been working in what many would consider a DevOps environment without calling it that. I really like Donovan Brown’s definition: “DevOps is the union of people, process, and products to enable continuous delivery of value to our end users.”
That sums it up nicely, but what are some of the “value” items that we can deliver to our customers? Today I want to discuss one of these: security.
The historical view of a secure system is one that gets secured, rarely changes, and every change allowed is reviewed to ensure no mistakes are made. That view fits fine in a DevOps software pipeline, well, except the rare part. Does that make a DevOps built application less secure? Let’s turn that around. Is a traditional (waterfall, agile, etc.) application more secure because of the limitations?
I’d argue it’s not. One of the issues with security is that the issues, holes, and vulnerabilities constantly change. What was secure last week might not be secure this week. In traditional applications we find one of two things. Since deployments are relatively rare, security problems often remain un-patched for long periods of time, or they are patched quickly by changes to production systems that are not well tested or evaluated. There are countless tales of changes made to production applications that end up breaking the system and must be removed. The result, a less secure system. This can be especially problematic when dependent software, for example the OpenSSL issues, is not patched because there are so many dependencies that no one is willing to change the system for fear of causing downtime.
In a mature DevOps environment, the system is better understood because the software is regularly built, testing is automated, and there are regular deployments to various downstream environments. Security patches can be incorporated and deployed quickly, enabling the ability of our automated testing process and intermediate environments to look for potential issues. With a regular branching strategy, we can even quickly suspend current development and focus on producing a patch or changing other code to ensure a successful deployment. Because we practice regular deployments, the need for un-tested, cowboy code changes in production is eliminated.
Certainly a DevOps process doesn’t preclude making mistakes. It doesn’t ensure developers or administrators won’t create vulnerabilities (intentional or accidental). DevOps doesn’t prevent mistakes. DevOps does ask us to continually learn and get feedback from our efforts. And it asks that we incorporate that feedback into our process. If we find a problem in how we write code, a test missed, or a problem in deployment, we correct that in our automated process to prevent it happening again. And since every task, every build, every deployment is logged, we can audit everyone’s actions. DevOps certainly encourages more security, though not perfect security. The goal is that a DevOps process gets us a little better security every time we learn something.