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Dropbox Can't See Your Dat– Er, Never Mind
bizwriter writes "Dropbox, the online backup and file sharing service claims to have hit 25 million users in a single year. But a change in terms, noting that Dropbox will give up data to law enforcement under a legal request, showed that the company's security claims couldn't be possible. It turns out that Dropbox claims in one place that encrypted data makes it impossible for employees to see into user files, but in another says that they're only 'prohibited' from doing so."
Everyday I get a corporate client asking me why they can't just do all their work on the cloud. Here's the perfect reason why.
When the foot seeks the place of the head, the line is crossed. Know your place. Keep your place. Be a shoe.
This is a common question, which I'm sure has come up in legal battles. When you upload data to someone else's server, does the data belong to you or does it belong to the person/company that actually owns the hardware? I'm sure for law enforcement folks, they want it both ways.
Consider if the data service in question is raided because an employee had child pornography. They raid the company because he employee used hardware to hid his stash. Now everyone's data is available for search.
IANAL but it seems like if you insist on using these services, you have to give up certain rights. Or you can just encrypt all of your data before uploading. But then, if the hardware is ceased, you no longer have a backup.
We don't live in Shouldland.
Of course it can be impossible. Encrypt the data yourself, using a well-known, open-source, trusted and verified program, and keep the keys yourself. Dropbox can't decrypt anything then. Why anyone would trust them in the first place, especially a smart guy like Miguel, is beyond me.
....AFAIK, Dropbox has full support for Truecrypt volumes. Simple solution to this delimma? Take the encryption "problem" away from Dropbox and use your own.
http://www.washingtonpost.com/wp-dyn/content/article/2007/03/22/AR2007032201882.html
Does that story give you the creeps or not?
So the government can make you rat on your clients and you can't even tell your own people your doing the work of the government
* Winners compare their achievements to their goals, losers compare theirs to that of others.
Dropbox lied. No two ways about it. But this why you never store anything sensitive in "the cloud" anyway.
Agile Artisans
Is this really dropbox or Amazon that is behind this policy? While people rant and rave about dropbox, in the end it's really just a fancy front end onto Amazon's S3 service. Your data is actually stored on Amazon's servers and my guess is that it's ultimately Amazon that dictates policies such as this.
Monstar L
Maybe it comes from working in IT, but I always assume that if someone else is holding my data, they can access it. It doesn't interest me what they say - that's my basic starting assumption. So I always assumed that Dropbox could get to my data, and if I cared about the privacy of that data I just encrypted the files myself first.
It's my data, I'm in control of it. Giving it up to someone else and hoping they keep it safe is silly.
I'm surprised so many people are surprised (and I wonder if the people are are surprised haven't been in IT long?)
Seriously, is anyone really surprised by this? I use DropBox, and not once have I considered that my data in DropBox is completely private. Sure, I use it for transferring some documents that are potentially sensitive (a lot of documentation on a lawsuit I'm involved in for example) but where there's sensitive data I always encrypt the documents myself with TrueCrypt.
This is precisely why I think the "cloud" is a bad idea for corporations. Until there are guarantees and safeguards against data theft or loss there is no way that I would entrust my company's critical data to a third party provider. Yes, the costs of managing that data myself are higher but the risk of that data getting out of our control and management is greatly mitigated.
And what about a data breach? Loss of data due to crackers? Seriously... all it's going to take is for one of these cloud providers to become big enough that the majority of corporations using their services are completely without options when a breach occurs. The big provider can simply turn around and say "Well, crap happens but who else are you going to turn to?" and there's nothing the average corporation can do about it. There may be financial guarantees in place, but simply put the cat is already out of the bag at that point.
I think the problem is that if you use a Truecrypt container and back that up to Dropbox, the Dropbox client is not always able to tell if any data has changed as changing the contents of the container does not always change the containers binary size on the disk. This means you can't do an incremental backup and instead have to force a full backup every time you alter what is inside the container, which isn't funny if your container is larger than a few hundred MBs.
This is the point of tarsnap. Open source client, you can verify it and the encryption that it uses. It encrypts everything before uploading and can't be decrypted on the server without access to a key that's only stored in the client.
I am TheRaven on Soylent News
That's the point. It looks for changes in the file. With encryption, the file usually *completely* changes, thus giving Dropbox no choice but to upload/download the whole thing.
The big deal is Dropbox' super simple interface, which integrates into your file system so even computer-illiterate people will have no problem using it, combined with the appeal of a pyramid scheme to get more free storage for every person you lure into using it. This makes every Dropbox user an advocate of Dropbox.
Pretty good is actually pretty bad.
With encryption, the file usually *completely* changes, thus giving Dropbox no choice but to upload/download the whole thing.
I've never used truecrypt, but from what I know, I suspect the chances of the entire encrypted volume changing when you make any change is close to zero. It would kill performance to have to rewrite the entire volume every time. It has to only update portions. So then the possible solution to this would be to treat it like bittorrent does, where it breaks it into chunks and checksums each chunk. When only a small portion of the file changes, it then know which chunks to reupload. Whether or not dropbox can or does operate this way, I have no idea, but in general, it is feasible to implement into a service.
Read the EULA.
Well, files put in DropBox are available on their website; it's pretty obvious that they can decrypt them. The encryption part is about the SSL connection between my client and the dropbox server, me thinks.
I have a dropbox account and don't remember seeing that section where they claimed they couldn't read my files. I'm certain I read it, but I never would have believed it to mean they were truly unable to read my files -- if they encrypted them before storing them, they'd have to be able to decrypt them to send them back to me, or to track changes. Did someone actually think they had an irreversible encryption process which could somehow be reversed by the magic between them and me? A one time pad which somehow evaporated while sending files back to me? It might be reasonable to think they have some sort of access controls so ordinary people there can't browser customer data, but I never would have put any ironclad faith in such policies. That's wy it was common knowledge, near as I could tell, all round the web that you needed to encrypt backups and such yourself before sending them to dropbox.
I don't understand why anyone would expect otherwise. This is a tempest in a teapot.
Infuriate left and right
Not for Truecrypt. In CBC mode it bases the initialization vector off of the hash of the file block address so only a single 4k block needs to get uploaded.
Does your family know that you think their photos are worthless? :)
simple, fast homepage with your links: http://www.ngumbi.com/
Take a look at SpiderOak (http://www.spideroak.com). Their fundamental security policy is "zero knowledge", meaning that their services works in such a way that everything is encrypted from the client. This is powerful stuff.
That's why if you use Dropbox or any other online storage with a closed-source client process, it should be used inside a virtual machine, with the virtual machine receiving encrypted files from the host OS. That way it can't sniff your password or any other data you don't want it to see.
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There is inferior bacteria on the interior of your posterior.
If you have the dropbox agent installed, how do you know anything on your computer is private?
-fb Everything not expressly forbidden is now mandatory.
They're not lying, they're just being careful with their words and people can't read.
It should be obvious to any technically-minded person that they hold any encryption keys, since when you install Dropbox on a second computer, you don't need to provide a key in order for it to be successful.
So their claims are that they encrypt data in transit, encrypt data at rest, and that employees can't access the content of files. There's no claim that it's impossible for any employee to access the content of files because they're encrypted with a key Dropbox doesn't hold, which is what people seem to be imagining. It's simply saying that employees won't snoop on your files because in the normal course of business, they are not provided access with the contents of those files.
As far as providing the files to law enforcement upon a legally-valid request, they don't really have a choice in the matter, as they're a US company. For any company that exists primarily in country X, it is almost certain that there is a relatively easy procedure for law enforcement agents of country X to obtain any data about you that the company holds. If the country happens to be, say, Lithuania, and you don't travel to or do business in Lithuania, you probably don't care, but it's still true. The only way to prevent this is to make it so that the company is not holding any useful data of yours that they are able to access. In the case of Dropbox, you need to encrypt your files before they get to Dropbox.
Incidentally, if you have data that you don't want law enforcement to be able to obtain, you should be encrypting it even when it's stored locally. A search warrant for your computer is not really all that much harder to obtain.
For all the above reasons I use encfs because it is only mounted when I choose, for just my eyes, and is easily backed up on a file by file basis so incremental backups work just fine. Just point your DropBox uploader to the encrypted file tree and back it up as soon as you unmount your crypto session volume. I have a script that mounts the crypto volume, opens a file manager to pause the script, and when the file manager is closed the session is immediately unmounted. All you need do is add a command to the end of the script to kick off a DropBox incremental upload.
Exactly! When I read the blog post, my first thought was, "Just another troll blogwhoring for attention on Slashdot." So I was a little surprised when I saw the author's name at the bottom. I use Dropbox for presentations that I give, so I don't have to mess with hooking up my laptop. I just use the public terminal, log in to Dropbox and download the file. I've never had to transfer a key or anything. Thus, it's pretty obvious that anybody with access to my account can access my files in plaintext.
Crypto is great and wonderful and all that, but it never exists in isolation. Access control policies, auditing, etc., are also required to have a secure, usable system that is flexible enough to provide the type of mobile access that Dropbox does. I see nothing contradictory about Dropbox's claims that employees cannot access user files directly. It seems to me that the author just never took the time to think about the implications of Dropbox's flexibility.
Much ado about nothing...
Depends on the encryption method you use
<shameless_plug>rsyncrypto</shameless_plug>
Shachar
It does let you choose though: privacy or convenience.
Come to think of it, that's a pretty common-place choice in life.
You may learn more if you do your own research but:
http://www.truecrypt.org/faq
[quote]The ciphertext block size used by TrueCrypt is 16 bytes (i.e., 128 bits)[/quote]
https://www.dropbox.com/help/8
[quote]Before transferring a file, we compare the new file to the previous version and only send the piece of the file that changed. This is called a "binary diff" and works on any file type. Dropbox compresses files before transferring them as well. This way, you also never have to worry about Dropbox re-uploading a file or wasting bandwidth.[/quote]