Fouilles des PC portables

[pankkake]

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

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 pgp.com). TrueCrypt (truecrypt.org) 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 tinyurl.com/4f8z4n.) 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.

· Bruce Schneier is a security technologist and author: schneier.com/blog

http://www.guardian.co.uk/technology/2008/…security?skljds

Tiens, qu'en est-il de la France pour les vols intérieurs ? J'aimerais bien prendre l'avion mais je préfère rater un vol que céder le moindre octet de données. Bon, je peux toujours user de la technique de l'article, qui est d'avoir un OS fonctionnel et une partition cachée, montable à la demande (et/ou une clé USB) avec mes véritables données.

Les gens ne se rendent pas compte de ce que ça représente - un PC est une mine hallucinante de données personnelles, et est souvent une porte ouverte vers tous ses comptes Internet (et son historique). Ou des secrets industriels. Ou des photos de votre copine nue. Etc.

C'est déjà arrivé que des agents fassent des copies entières des données des gens, ou prennent les PC sans montrer ce qu'ils en font.

Et je ne parle pas des réparations des PC : il est arrivé plusieurs fois que des réparateurs volent des données à leur clients (évitez donc d'avoir vos photos compromettantes, parce qu'elles se retrouveront partout sur Internet dans les trois jours).

[pankkake]

Un commentaire sur reddit:

While it makes for a funny joke - I have to report that my laptop was searched in front of me in Canada (Ottawa). It was one of the scariest moments of my life. Not because I had anything illegal, but just to see someone casually rooting through the pr0n, clinical and suggestive (they said they were looking for kiddie porn and beasiality), all the time me asking myself "why did they pick me?". I can't state how much this sucks, and how much I felt violated. Thy searched in an area near customs where another person (including a couple on vacation, it seems) could easily lean over and see what the guard was looking at.

I think this practice is disgusting and they should stick to regular sleuthing, if they even know how anymore.

After I was cleared they were all lollipops and smiles. But I still felt used.

De plus :

Customs will attach a USB drive to your computer and use software contained therein to access your drive.

How do you know they aren't installing a backdoor on your laptop?

[Sous-Commandant Marco]

Le site de l'auteur a l'air intéressant:

http://www.schneier.com/

[Sekonda]

Le site de l'auteur a l'air intéressant:

http://www.schneier.com/

Oui, Bruce Schneier est une référence pour la crypto et la sécurité.

[Sous-Commandant Marco]

Oui, Bruce Schneier est une référence pour la crypto et la sécurité.

[…]

Il est aussi l'inventeur de l'individu-i, un caractère d'imprimerie qui représente les droits inviduels:

http://www.individual-i.com

[Herbert West]

Et à la lecture de ses bouquins, je dirais que Schneier est plus ou moins libertarien (mais sans jamais vraiment l'avouer ; peut-être parce qu'il bosse pour des grosses boites proches du gouvernement US).

Sinon, le meilleur moyen d'éviter ce genre de problèmes est, je pense, de chiffrer sa partition de travail et de laisser une partition bateau en clair avec deux/trois jeux et autres conneries (on peut imaginer par exemple que le bootloader démarre sur la partition en clair si la passphrase de la vraie partition est erronée).

[Sekonda]

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.

Encore une fois, chiffrement niable (voir ce fil). Sinon comme il le dit à la fin, PC "propre" et connexion à un stockage en ligne par VPN.

Concernant les vols intérieurs, il n'y a rien en France à ma connaissance même si le risque que cela soit possible à moyen terme est fort.