Entries Tagged "cryptography"

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Seagate's Full Disk Encryption

Seagate has introduced a hard drive with full-disk encryption.

The 2.5-inch drive offers full encryption of all data directly on the drive through a software key that resides on a portion of the disk nobody but the user can access. Every piece of data that crosses the interface encrypted without any intervention by the user, said Brian Dexheimer, executive vice president for global sales and marketing at the Scotts Valley, Calif.-based company.

Here’s the press release, and here’s the product spec sheet. Ignore the “TDEA 192” nonsense. It’s a typo; the product uses triple-DES, and the follow-on product will use AES.

Posted on June 27, 2005 at 7:24 AMView Comments

SHA Cryptanalysis Paper Online

In February, I wrote about a group of Chinese researchers who broke the SHA-1 hash function. That posting was based on short notice from the researchers. Since then, many people have written me asking about the research and the actual paper, some questioning the validity of the research because of the lack of documentation.

The paper did exist; I saw a copy. They will present it at the Crypto conference in August. I believe they didn’t post it because Crypto requires that submitted papers not be previously published, and they misunderstood that to mean that it couldn’t be widely distributed in any way.

Now there’s a copy of the paper on the web. You can read “Finding Collisions in the Full SHA-1,” by Xiaoyun Wang, Yiqun Lisa Yin, and Hongbo Yu, here.

Posted on June 24, 2005 at 12:46 PMView Comments

Password Safe

Password Safe is a free Windows password-storage utility. These days, anyone who is on the Web regularly needs too many passwords, and it’s impossible to remember them all. I have long advocated writing them all down on a piece of paper and putting it in your wallet.

I designed Password Safe as another solution. It’s a small program that encrypts all of your passwords using one passphrase. The program is easy to use, and isn’t bogged down by lots of unnecessary features. Security through simplicity.

Password Safe 2.11 is now available.

Currently, Password Safe is an open source project at SourceForge, and is run by Rony Shapiro. Thank you to him and to all the other programmers who worked on the project.

Note that my Password Safe is not the same as this, this, this, or this PasswordSafe. (I should have picked a more obscure name for the program.)

It is the same as this, for the PocketPC.

Posted on June 15, 2005 at 1:35 PMView Comments

Attack on the Bluetooth Pairing Process

There’s a new cryptographic result against Bluetooth. Yaniv Shaked and Avishai Wool of Tel Aviv University in Israel have figured out how to recover the PIN by eavesdropping on the pairing process.

Pairing is an important part of Bluetooth. It’s how two devices—a phone and a headset, for example—associate themselves with one another. They generate a shared secret that they use for all future communication. Pairing is why, when on a crowded subway, your Bluetooth devices don’t link up with all the other Bluetooth devices carried by everyone else.

According to the Bluetooth specification, PINs can be 8-128 bits long. Unfortunately, most manufacturers have standardized on a four decimal-digit PIN. This attack can crack that 4-digit PIN in less than 0.3 sec on an old Pentium III 450MHz computer, and in 0.06 sec on a Pentium IV 3Ghz HT computer.

At first glance, this attack isn’t a big deal. It only works if you can eavesdrop on the pairing process. Pairing is something that occurs rarely, and generally in the safety of your home or office. But the authors have figured out how to force a pair of Bluetooth devices to repeat the pairing process, allowing them to eavesdrop on it. They pretend to be one of the two devices, and send a message to the other claiming to have forgotten the link key. This prompts the other device to discard the key, and the two then begin a new pairing session.

Taken together, this is an impressive result. I can’t be sure, but I believe it would allow an attacker to take control of someone’s Bluetooth devices. Certainly it allows an attacker to eavesdrop on someone’s Bluetooth network.

News story here.

Posted on June 3, 2005 at 10:19 AMView Comments

Eric Schmidt on Secrecy and Security

From Information Week:

InformationWeek: What about security? Have you been paying as much attention to security as, say Microsoft—you can debate whether or not they’ve been successful, but they’ve poured a lot of resources into it.

Schmidt: More people to a bad architecture does not necessarily make a more secure system. Why don’t you define security so I can answer your question better?

InformationWeek: I suppose it’s an issue of making the technology transparent enough that people can deploy it with confidence.

Schmidt: Transparency is not necessarily the only way you achieve security. For example, part of the encryption algorithms are not typically made available to the open source community, because you don’t want people discovering flaws in the encryption.

Actually, he’s wrong. Everything about an encryption algorithm should always be made available to everyone, because otherwise you’ll invariably have exploitable flaws in your encryption.

My essay on the topic is here.

Posted on May 31, 2005 at 1:09 PMView Comments

AES Timing Attack

Nice timing attack against AES.

For those of you who don’t know, timing attacks are an example of side-channel cryptanalysis: cryptanalysis using additional information about the inner workings of the cryptographic algorithm. I wrote about them here.

What’s the big idea here?

There are two ways to look at a cryptographic primitive: block cipher, digital signature function, whatever. The first is as a chunk of math. The second is a physical (or software) implementation of that math.

Traditionally, cryptanalysis has been directed solely against the math. Differential and linear cryptanalysis are good examples of this: high-powered mathematical tools that can be used to break different block ciphers.

On the other hand, timing attacks, power analysis, and fault analysis all makes assumptions about implementation, and uses additional information garnered from attacking those implementations. Failure analysis assumes a one-bit feedback from the implementation—was the message successfully decrypted—in order to break the underlying cryptographic primitive. Timing attacks assumes that an attacker knows how long a particular encryption operation takes.

Posted on May 17, 2005 at 10:05 AMView Comments

Sidebar photo of Bruce Schneier by Joe MacInnis.