The NSA’s Domestic Cybersecurity Surveillance

Earlier today, the New York Times reported that the National Security Agency has secretly expanded its role in domestic cybersecurity. In short, the NSA believes it has authority to operate a warrantless, signature-based intrusion detection system—on the Internet backbone.1

Owing to the program’s technical and legal intricacies, the Times-ProPublica team sought my explanation of related primary documents.2 I have high confidence in the report’s factual accuracy.3

Since this morning’s coverage is calibrated for a general audience, I’d like to provide some additional detail. I’d also like to explain why, in my view, the news is a game-changer for information sharing legislation.


“We Support Strong Encryption”

A good Washington talking point delivers zero content. A great Washington talking point sounds substantive… while delivering zero content.

In the spirit of honoring greatness, I’d like to call attention to the current White House position on cryptographic backdoors. It received its most public airing from President Obama, in a February 13 interview with RE/CODE.

“I’m a strong believer in strong encryption,” explained the President. “[T]here’s no scenario in which we don’t want really strong encryption.”

President Obama isn’t the only official invoking “strong encryption.” (And strongly, too.) In just about every recent conversation with an administration policymaker, I’ve been subjected to some version of the line.

You Can’t Backdoor a Platform

According to law enforcement and intelligence agencies, encryption should come with a backdoor. It’s not a new policy position—it dates to the Crypto Wars of the 1990s—but it’s gaining new Beltway currency.

Cryptographic backdoors are a bad idea. They introduce unquantifiable security risks, like the recent FREAK vulnerability. They could equip oppressive governments, not just the United States. They chill free speech. They impose costs on innovators and reduce foreign demand for American products. The list of objections runs long.

I’d like to articulate an additional, pragmatic argument against backdoors. It’s a little subtle, and it cuts across technology, policy, and law. Once you see it, though, you can’t unsee it.

Cryptographic backdoors will not work. As a matter of technology, they are deeply incompatible with modern software platforms. And as a matter of policy and law, addressing those incompatibilities would require intolerable regulation of the technology sector. Any attempt to mandate backdoors will merely escalate an arms race, where usable and secure software stays a step ahead of the government.

The easiest way to understand the argument is to walk through a hypothetical. I’m going to use Android; much of the same analysis would apply to iOS or any other mobile platform.

Saving Your Cryptographic Front Door

Does the Fourth Amendment protect SSL keys? Not really, argues the executive branch in Lavabit’s appeal. “[A] business cannot prevent the execution of a search warrant by locking its front gate.”1

True enough. But a business does have a constitutional right to keep that gate intact. When executing a warrant, officers must ordinarily announce themselves and afford an opportunity to open up.