23Protecting the Deployment Pipeline

Throughout this chapter we will look at how to protect our deployment pipeline, as well as how to acheive security and compliance objectives in our control environment, including change management and separation of duty.

INTEGRATE SECURITY AND COMPLIANCE INTO CHANGE APPROVAL PROCESSES

Almost any IT organization of any significant size will have existing change management processes, which are the primary controls to reduce operations and security risks. Compliance manager and security managers place reliance on change management processes for compliance requirements, and they typically require evidence that all changes have been appropriately authorized.

If we have constructed our deployment pipeline correctly so that deployments are low-risk, the majority of our changes won’t need to go through a manual change approval process, because we will have placed our reliance on controls such as automated testing and proactive production monitoring.

In this step, we will do what is required to ensure that we can successfully integrate security and compliance into any existing change management process. Effective change management policies will recognize that there are different risks associated with different types of changes and that those changes are all handled differently. These processes are defined in ITIL, which breaks changes down into three categories:

RE-CATEGORIZE THE MAJORITY OF OUR LOWER RISK CHANGES AS STANDARD CHANGES

Ideally, by having a reliable deployment pipeline in place, we will have already earned a reputation for fast, reliable, and non-dramatic deployments. At this point, we should seek to gain agreement from Operations and the relevant change authorities that our changes have been demonstrated to be low risk enough to be defined as standard changes, pre-approved by the CAB. This enables us to deploy into production without need for further approval, although the changes should still be properly recorded.

One way to support an assertion that our changes are low risk is to show a history of changes over a significant time period (e.g., months or quarters) and provide a complete list of production issues during that same period. If we can show high change success rates and low MTTR, we can assert that we have a control environment that is effectively preventing deployment errors, as well as prove that we can effectively and quickly detect and correct any resulting problems.

Even when our changes are categorized as standard changes, they still need to be visual and recorded in our change management systems (e.g., Remedy or ServiceNow). Ideally, deployments will be performed automatically by our configuration management and deployment pipeline tools (e.g., Puppet, Chef, Jenkins) and the results will be automatically recorded. By doing this, everyone in our organization (DevOps or not) will have visibility into our changes in addition to all the other changes happening in the organization.

We may automatically link these change request records to specific items in our work planning tools (e.g., JIRA, Rally, LeanKit, ThoughtWorks Mingle), allowing us to create more context for our changes, such as linking to feature defects, production incidents, or user stories. This can be accomplished in a lightweight way by including ticket numbers from planning tools in the comments associated with version control check ins.§ By doing this, we can trace a production deployment to the changes in version control and, from there, trace them further back to the planning tool tickets.

Creating this traceability and context should be easy and should not create an overly onerous or time-consuming burden for engineers. Linking to user stories, requirements, or defects is almost certainly sufficient—any further detail, such as opening a ticket for each commit to version control, is likely not useful, and thus unnecessary and undesired, as it will impose a significant level of friction on their daily work.

WHAT TO DO WHEN CHANGES ARE CATEGORIZED AS NORMAL CHANGES

For those changes that we cannot get classified as standard changes, they will be considered normal changes and will require approval from at least a subset of the CAB before deployment. In this case, our goal is still to ensure that we can deploy quickly, even if it is not fully automated.

In this case, we must ensure that any submitted change requests are as complete and accurate as possible, giving the CAB everything they need to properly evaluate our change—after all, if our change request is malformed or incomplete, it will be bounced back to us, increasing the time required for us to get into production and casting doubt on whether we actually understand the goals of the change management process.

We can almost certainly automate the creation of complete and accurate RFCs, populating the ticket with details of exactly what is to be changed. For instance, we could automatically create a ServiceNow change ticket with a link to the JIRA user story, along with the build manifests and test output from our deployment pipeline tool and links to the Puppet/Chef scripts that will be run.

Because our submitted changes will be manually evaluated by people, it is even more important that we describe the context of the change. This includes identifying why we are making the change (e.g., providing a link to the features, defects, or incidents), who is affected by the change, and what is going to be changed.

Our goal is to share the evidence and artifacts that give us confidence that the change will operate in production as designed. Although RFCs typically have free-form text fields, we should provide links to machine-readable data to enable others to integrate and process our data (e.g., links to JSON files).

In many toolchains, this can be done in a compliant and fully automated way. For example, ThoughtWorks’ Mingle and Go can automatically link this information together, such as a list of defects fixed and new features completed that are associated with the change, and put it into an RFC.

Upon submission of our RFC, the relevant members of the CAB will review, process, and approve these changes as they would any other submitted change request. If all goes well, the change authorities will appreciate the thoroughness and detail of our submitted changes, because we have allowed them to quickly validate the correctness of the information we’ve provided (e.g., viewing the links to artifacts from our deployment pipeline tools). However, our goal should be to continually show an exemplary track record of successful changes, so we can eventually gain their agreement that our automated changes can be safely classified as standard changes.

Case Study
Automated Infrastructure Changes as Standard Changes at Salesforce.com (2012)

Salesforce was founded in 2000 with the aim of making customer relationship management easily available and deliverable as a service. Salesforce’s offerings were widely adopted by the marketplace, leading to a successful IPO in 2004. By 2007, the company had over fifty-nine thousand enterprise customers, processing hundreds of millions of transactions per day, with annual revenue of $497 million.

However, around that same time, their ability to develop and release new functionality to their customers seemed to grind to a halt. In 2006, they had four major customer releases, but in 2007 they were only able to do one customer release despite having hired more engineers. The result was that the number of features delivered per team kept decreasing and the days between major releases kept increasing.

And because the batch size of each release kept getting larger, the deployment outcomes also kept getting worse. Karthik Rajan, then VP of Infrastructure Engineering, reports in a 2013 presentation that 2007 marked “the last year when software was created and shipped using a waterfall process and when we made our shift to a more incremental delivery process.”

At the 2014 DevOps Enterprise Summit, Dave Mangot and Reena Mathew described the resulting multi-year DevOps transformation that started in 2009. According to Mangot and Mathew, by implementing DevOps principles and practices, the company reduced their deployment lead times from six days to five minutes by 2013. As a result, they were able to scale capacity more easily, allowing them to process over one billion transactions per day.

One of the main themes of the Salesforce transformation was to make quality engineering everyone’s job, regardless of whether they were part of Development, Operations, or Infosec. To do this, they integrated automated testing into all stages of the application and environment creation, as well as into the continuous integration and deployment process, and created the open source tool Rouster to conduct functional testing of their Puppet modules.

They also started to routinely perform destructive testing, a term used in manufacturing to refer to performing prolonged endurance testing under the most severe operating conditions until the component being tested is destroyed. The Salesforce team started routinely testing their services under increasingly higher loads until the service broke, which helped them understand their failure modes and make appropriate corrections. Unsurprisingly, the result was significantly higher service quality with normal production loads.

Information Security also worked with Quality Engineering at the earliest stages of their project, continually collaborating in critical phases such as architecture and test design, as well as properly integrating security tools into the automated testing process.

For Mangot and Mathew, one of the key successes from all the repeatability and rigor they designed into the process was being told by their change management group that “infrastructure changes made through Puppet would now be treated as ‘standard changes,’ requiring far less or even no further approvals from the CAB.” Furthermore, they noted that “manual changes to infrastructure would still require approvals.”

By doing this, they had not only integrated their DevOps processes with the change management process, but also created further motivation to automate the change process for more of their infrastructure.

REDUCE RELIANCE ON SEPARATION OF DUTY

For decades, we have used separation of duty as one of our primary controls to reduce the risk of fraud or mistakes in the software development process. It has been the accepted practice in most SDLCs to require developer changes to be submitted to a code librarian, who would review and approve the change before IT Operations promoted the change into production.

There are plenty of other less contentious examples of separation of duty in Ops work, such as server administrators ideally being able to view logs but not delete or modify them, in order to prevent someone with privileged access from deleting evidence of fraud or other issues.

When we did production deployments less frequently (e.g., annually) and when our work was less complex, compartmentalizing our work and doing hand-offs were tenable ways of conducting business. However, as complexity and deployment frequency increase, performing production deployments successfully increasingly requires everyone in the value stream to quickly see the outcomes of their actions.

Separation of duty often can impede this by slowing down and reducing the feedback engineers receive on their work. This prevents engineers from taking full responsibility for the quality of their work and reduces a firm’s ability to create organizational learning.

Consequently, wherever possible, we should avoid using separation of duties as a control. Instead, we should choose controls such as pair programming, continuous inspection of code check-ins, and code review. These controls can give us the necessary reassurance about the quality of our work. Furthermore, by putting these controls in place, if separation of duties is required, we can show that we achieve equivalent outcomes with the controls we have created.

Case Study
PCI Compliance and a Cautionary Tale of Separating Duties at Etsy (2014)

Bill Massie is a development manager at Etsy and is responsible for the payment application called ICHT (an abbreviation for “I Can Haz Tokens”). ICHT takes customer credit orders through a set of internally-developed payment processing applications that handle online order entry by taking customer-entered cardholder data, tokenizing it, communicating with the payment processor, and completing the order transaction.

Because the scope of the Payment Card Industry Data Security Standards (PCI DSS) cardholder data environment (CDE) is “the people, processes and technology that store, process or transmit cardholder data or sensitive authentication data,” including any connected system components, the ICHT application has in scope for the PCI DSS.

To contain the PCI DSS scope, the ICHT application is physically and logically separated from the rest of the Etsy organization and is managed by a completely separate application team of developers, database engineers, networking engineers, and ops engineers. Each team member is issued two laptops: one for ICHT (which are configured differently to meet the DSS requirements, as well as being locked in a safe when not in use) and one for the rest of Etsy.

By doing this, they were able to decouple the CDE environment from the rest of the Etsy organization, limiting the scope of the PCI DSS regulations to one segregated area. The systems that form the CDE are separated (and managed differently) from the rest of Etsy’s environments at the physical, network, source code, and logical infrastructure levels. Furthermore, the CDE is built and operated by a cross-functional team that is solely responsible for the CDE.

The ICHT team had to modify their continuous delivery practices in order to accommodate the need for code approvals. According to Section 6.3.2 of the PCI DSS v3.1, teams should review:

All custom code prior to release to production or customers in order to identify any potential coding vulnerability (using either manual or automated processes) as follows:

To fulfill this requirement, the team initially decided to designate Massie as the change approver responsible for deploying any changes into production. Desired deployments would be flagged in JIRA, and Massie would mark them as reviewed and approved, and manually deploy them into the ICHT production.

This has enabled Etsy to meet their PCI DSS requirements and get their signed Report of Compliance from their assessors. However, with regard to the team, significant problems have resulted.

Massie observes that one troubling side effect “is a level of ‘compartmentalization’ that is happening in the ICHT team that no other group is having at Etsy. Ever since we implemented separation of duty and other controls required by the PCI DSS compliance, no one can be a full-stack engineer in this environment.”

As a result, while the rest of the Development and Operations teams at Etsy work together closely and deploy changes smoothly and with confidence, Massie notes that “within our PCI environment, there is fear and reluctance around deployment and maintenance because no one has visibility outside their portion of the software stack. The seemingly minor changes we made to the way we work seem to have created an impenetrable wall between developers and ops, and creates an undeniable tension that no one at Etsy has had since 2008. Even if you have confidence in your portion, it’s impossible to get confidence that someone else’s change isn’t going to break your part of the stack.”

This case study shows that compliance is possible in organizations using DevOps. However, the potentially cautionary tale here is that all the virtues that we associate with high-performing DevOps teams are fragile—even a team that has shared experiences with high trust and shared goals can begin to struggle when low trust control mechanisms are put into place.

ENSURE DOCUMENTATION AND PROOF FOR AUDITORS AND COMPLIANCE OFFICERS

As technology organizations increasingly adopt DevOps patterns, there is more tension than ever between IT and audit. These new DevOps patterns challenge traditional thinking about auditing, controls, and risk mitigation.

As Bill Shinn, a principal security solutions architect at Amazon Web Services, observes, “DevOps is all about bridging the gap between Dev and Ops. In some ways, the challenge of bridging the gap between DevOps and auditors and compliance officers is even larger. For instance, how many auditors can read code and how many developers have read NIST 800-37 or the Gramm-Leach-Bliley Act? That creates a gap of knowledge, and the DevOps community needs to help bridge that gap.”

Case Study
Proving Compliance in Regulated Environments (2015)

Helping large enterprise customers show that they can still comply with all relevant laws and regulations is among Bill Shinn’s responsibilities as a principal security solutions architect at Amazon Web Services. Over the years, he has spent time with over one thousand enterprise customers, including Hearst Media, GE, Phillips, and Pacific Life, who have publicly referenced their use of public clouds in highly regulated environments.

Shinn notes, “One of the problems is that auditors have been trained in methods that aren’t very suitable for DevOps work patterns. For example, if an auditor saw an environment with ten thousand productions servers, they have been traditionally trained to ask for a sample of one thousand servers, along with screenshot evidence of asset management, access control settings, agent installations, server logs, and so forth.”

“That was fine with physical environments,” Shinn continues. “But when infrastructure is code, and when auto-scaling makes servers appear and disappear all the time, how do you sample that? You run into the same problems when you have a deployment pipeline, which is very different than the traditional software development process, where one group writes the code and another group deploys that code into production.”

He explains, “In audit fieldwork, the most commonplace methods of gathering evidence are still screenshots and CSV files filled with configuration settings and logs. Our goal is to create alternative methods of presenting the data that clearly show auditors that our controls are operating and effective.”

To help bridge that gap, he has teams work with auditors in the control design process. They use an iterative approach, assigning a single control for each sprint to determine what is needed in terms of audit evidence. This has helped ensure that auditors get the information they need when the service is in production, entirely on demand.

Shinn states that the best way to accomplish this is to “send all data into our telemetry systems, such as Splunk or Kibana. This way auditors can get what they need, completely self-serviced. They don’t need to request a data sample—instead, they log into Kibana, and then search for audit evidence they need for a given time range. Ideally, they’ll see very quickly that there’s evidence to support that our controls are working.”

Shinn continues, “With modern audit logging, chat rooms, and deployment pipelines, there’s unprecedented visibility and transparency into what’s happening in production, especially compared to how Operations used to be done, with far lower probability of errors and security flaws being introduced. So, the challenge is to turn all that evidence into something an auditor recognizes.”

That requires deriving the engineering requirements from the actual regulations. Shinn explains, “To discover what HIPAA requires from an information security perspective, you have to look into the forty-five CFR Part 160 legislation, go into Subparts A and C of Part 164. Even then, you need to keep reading until you get into ‘technical safeguards and audit controls.’ Only there will you see that what is required is that we need to determine activities that will be tracked and audited relevant to Patient Healthcare Information, document and implement those controls, select tools, and then finally review and capture the appropriate information.”

Shinn continues, “How to fulfill that requirement is the discussion that needs to be happening between compliance and regulatory officers, and the security and DevOps teams, specifically around how to prevent, detect, and correct problems. Sometimes they can be fulfilled in a configuration setting in version control. Other times, it’s a monitoring control.”

Shinn gives an example: “We may choose to implement one of those controls using AWS CloudWatch, and we can test that the control is operating with one command line. Furthermore, we need to show where the logs are going—in the ideal, we push all this into our logging framework, where we can link the audit evidence with the actual control requirement.”

To help solve this problem, the DevOps Audit Defense Toolkit describes the end-to-end narrative of the compliance and audit process for a fictitious organization (Parts Unlimited from The Phoenix Project). It starts by describing the entity’s organizational goals, business processes, top risks, and resulting control environment, as well as how management could successfully prove that controls exist and are effective. A set of audit objections is also presented, as well as how to overcome them.

The document describes how controls could be designed in a deployment pipeline to mitigate the stated risks, and provides examples of control attestations and control artifacts to demonstrate control effectiveness. It was intended to be general to all control objectives, including in support of accurate financial reporting, regulatory compliance (e.g., SEC SOX-404, HIPAA, FedRAMP, EU Model Contracts, and the proposed SEC Reg-SCI regulations), contractual obligations (e.g., PCI DSS, DOD DISA), and effective and efficient operations.

Case Study
Relying on Production Telemetry for ATM Systems

Mary Smith (a pseudonym) heads up the DevOps initiative for the consumer banking property of a large US financial services organization. She made the observation that information security, auditors, and regulators often put too much reliance on code reviews to detect fraud. Instead, they should be relying on production monitoring controls in addition to using automated testing, code reviews, and approvals, to effectively mitigate the risks associated with errors and fraud.

She observed:

Many years ago, we had a developer who planted a backdoor in the code that we deploy to our ATM cash machines. They were able to put the ATMs into maintenance mode at certain times, allowing them to take cash out of the machines. We were able to detect the fraud very quickly, and it wasn’t through a code review. These types of backdoors are difficult, or even impossible, to detect when the perpetrators have sufficient means, motive, and opportunity.

However, we quickly detected the fraud during our regularly operations review meeting when someone noticed that ATMs in a city were being put into maintenance mode at unscheduled times. We found the fraud even before the scheduled cash audit process, when they reconcile the amount of cash in the ATMs with authorized transactions.

In this case study, the fraud occurred despite separation of duties between Development and Operations and a change approval process, but was quickly detected and corrected through effective production telemetry.

CONCLUSION

Throughout this chapter, we have discussed practices that make information security everyone’s job, where all of our information security objectives are integrated into the daily work of everyone in the value stream. By doing this, we significantly improve the effectiveness of our controls, so that we can better prevent security breaches, as well as detect and recover from them faster. And we significantly reduce the work associated with preparing and passing compliance audits.

PART VI CONCLUSION

Throughout the previous chapters, we explored how to take DevOps principles and apply them to Information Security, helping us achieve our goals, and making sure security is a part of everyone’s job, every day. Better security ensures that we are defensible and sensible with our data, that we can recover from security problems before they become catastrophic, and, most importantly, that we can make the security of our systems and data better than ever.