This is a war they cannot win

May 15th, 2008

Taking your laptop into the US? Be sure to hide all your data first

By Bruce Schneier
The Guardian
May 15 2008

Last month a US court ruled that border agents can search your laptop, or any other electronic device, when you’re entering the country. They can take your computer and download its entire contents, or keep it for several days. Customs and Border Patrol has not published any rules regarding this practice, and I and others have written a letter to Congress urging it to investigate and regulate this practice.

But the US is not alone. British customs agents search laptops for pornography. And there are reports on the internet of this sort of thing happening at other borders, too. You might not like it, but it’s a fact. So how do you protect yourself?

Encrypting your entire hard drive, something you should certainly do for security in case your computer is lost or stolen, won’t work here. The border agent is likely to start this whole process with a “please type in your password”. Of course you can refuse, but the agent can search you further, detain you longer, refuse you entry into the country and otherwise ruin your day.

You’re going to have to hide your data. Set a portion of your hard drive to be encrypted with a different key – even if you also encrypt your entire hard drive – and keep your sensitive data there. Lots of programs allow you to do this. I use PGP Disk (from TrueCrypt ( is also good, and free.

While customs agents might poke around on your laptop, they’re unlikely to find the encrypted partition. (You can make the icon invisible, for some added protection.) And if they download the contents of your hard drive to examine later, you won’t care.

Be sure to choose a strong encryption password. Details are too complicated for a quick tip, but basically anything easy to remember is easy to guess. (My advice is at Unfortunately, this isn’t a perfect solution. Your computer might have left a copy of the password on the disk somewhere, and (as I also describe at the above link) smart forensic software will find it.

So your best defence is to clean up your laptop. A customs agent can’t read what you don’t have. You don’t need five years’ worth of email and client data. You don’t need your old love letters and those photos (you know the ones I’m talking about). Delete everything you don’t absolutely need. And use a secure file erasure program to do it. While you’re at it, delete your browser’s cookies, cache and browsing history. It’s nobody’s business what websites you’ve visited. And turn your computer off – don’t just put it to sleep – before you go through customs; that deletes other things. Think of all this as the last thing to do before you stow your electronic devices for landing. Some companies now give their employees forensically clean laptops for travel, and have them download any sensitive data over a virtual private network once they’ve entered the country. They send any work back the same way, and delete everything again before crossing the border to go home. This is a good idea if you can do it.

If you can’t, consider putting your sensitive data on a USB drive or even a camera memory card: even 16GB cards are reasonably priced these days. Encrypt it, of course, because it’s easy to lose something that small. Slip it in your pocket, and it’s likely to remain unnoticed even if the customs agent pokes through your laptop. If someone does discover it, you can try saying: “I don’t know what’s on there. My boss told me to give it to the head of the New York office.” If you’ve chosen a strong encryption password, you won’t care if he confiscates it.

Lastly, don’t forget your phone and PDA. Customs agents can search those too: emails, your phone book, your calendar. Unfortunately, there’s nothing you can do here except delete things.

I know this all sounds like work, and that it’s easier to just ignore everything here and hope you don’t get searched. Today, the odds are in your favour. But new forensic tools are making automatic searches easier and easier, and the recent US court ruling is likely to embolden other countries. It’s better to be safe than sorry.


We of course, have written about this before, September 12th 2006 to be exact, and the solution we give is more or less the same.

There is one solution however, that is not on the table in this great article; do not travel to places where these practices are in place. But that is a different blog post.

It is obvious to even the most stupid person that searching a laptop for pornography is TOTALLY STUPID. Pr0n travels over the internetz, and the really devious pr0n people use encrypted VPN to share their stuff. All these measures do is industrialize humiliation and violation. It is pointless, corrosive and the act of utterly incompetent and ignorant people.

This is a war that they will never win. Storage devices are getting bigger in capacity whilst shrinking in size, and people are getting more and more savvy about storing all their goods online; soon, many people will not use any office suites on their laptops, they will access an online office suite securely. That means they will have secure access to massive file storage, and if the files are encrypted before they are stored online, no warrant can cause them to be opened, and there will be no covert ‘sneak and peek‘ raids that obtain anything of value.

In the end, privacy will win, because the tools will make it happen. All of these insane measures simply accelerate the development of the tools and their byproduct: privacy.

Who would have thought that PGP would spread as far and wide as it has? And now, with articles like this appearing in even the shittiest of newspapers, it will spread even further, as companies demand that their laptops are locked down, and individuals start to protect themselves with these easy to use, military grade, transparent tools.

On a side note, you will see that Bruce has used a Tinyurl in this article. That is what smart people do. To my utter amazement, people who run email lists that are concerned with these issues STILL sent out alerts that have long line wrapped URLs, making them unclickable, and of course, because they are line wrapped, you cannot select them in one go, you have to select copy and paste twice. It is a minor annoyance, but it displays something about them and their attitude and level of competence. They certainly know about Tinyurl, so do they not use it because they are lazy? I think that actually, they are just plain dumb; as dumb as the people who think searching laptops at a border is a good idea, but they are batting for the other side.

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