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Comment: Re:How can you search data (Score 2) 90

Why is this even a thing? All reversible encryption (which in itself is a tautology) is searchable.

Plaintext record ID > Encryption+key+salt etc > Cyphertext record ID. Search for the cyphertext record ID. Bring encrypted record back from database. Encrypted record > Encryption > Plaintext record.

How is this a marketable product?!

Searchable encryption is more complicated than you think. For example if I encrypt the sentence "I like reading slashot" with traditional encryption I will get a block binary data that is meaningless. Now suppose I want to check if that block contains the word "slashdot"? Your "cyphertext record id" approach won't be of much help. You need a few tricks to do it correctly, notably adding some metadata and additional cryptographic mechanisms. To make things more complicated, you often need the encryption mechanism to be "format preserving": if you encrypt a string field you get a string field, if you encrypt a number field you get a number field, while traditional cryptography outputs binary data.

Note that you may have misunderstand how encryption works, if you believe that all reversible encryption is searchable. Good encryption is randomised: if you encrypt the same plaintext twice with the same key you get 2 different cypher-texts (to take your analogy, you must use different salts).

+ - Google fined by French Privacy regulator, notice to be published on homepage.

Submitted by L-One-L-One
L-One-L-One (173461) writes "Following similar decisions in Spain and the Netherlands, Google was fined today 150,000 euros by the French Data Protection authority for breaching data protection legislation. This sanction follows a long enquiry triggered by Google's decision to change its privacy policy in March 2012. The authority notably considers that the new policy "does not sufficiently inform its users of the conditions in which their personal data are processed, nor of the purposes of this processing", and that Google combines "all the data it collects about its users across all of its services without any legal basis". While the fine may be barely noticeable for Google, the authority requires the search giant to publish this decision on Google's French homepage, google.fr for 48 hours within the next 8 days."

Comment: Hashing is not better than encryption! (Score 2) 230

by L-One-L-One (#45338593) Attached to: Stolen Adobe Passwords Were Encrypted, Not Hashed

In practice hashing is often much less secure than encryption for passwords. The devil is in the details.

Here it seems that Adobe made some poor design choices in the encryption algorithm. Yet, despite these flaws, assuming the encryption key is not compromised they might still be better off with their encryption rather than a poor hash mechanism such as the one used for example by Sony and revealed in the playstation hack by anonymous.

In general if the encryption key is not compromised, then encryption provides much more security than pure hashing, or even hashing with a salt. The reason for that is that with encryption, the security of the password depends on the strength of the secret key. With hashing, the security depends of the strength of the password. This is a significant difference. So, if your password is 4 characters long, even the best hash algorithm will fail to protect from a brute force attack. However, if that same password is encrypted, you need to brute force the key which would take centuries assuming the key is long enough.

To be more precise:
1) Pure hashing (applying SHA1 alone for example) is almost the same as having no security at all.
2) Hashing with a salt is a bit better but still won't resist long given computational power offered by GPUs and cloud computing.
3) An iterated hash function with a salt is much better (see PKDF2), and buys you some security but still vulnerable from brute force attacks using GPUs and pooled cloud resources.
4) A "sequential memory-hard" hash function (with salt and iteration) such as "scrypt" is pretty safe today.

Unfortunately in reality most companies use either (1) or (2)...

The drawback of encryption is that you need to make sure that your key is safe. Once the key is compromised you're toast. This means that you should not put the key on the same system that is hosting the password database (it may sound evident, but I've seen it done). It requires putting the key in a HSM (Hardware Security Module) or in a distinct ultra secure server, distinct from the password database.

Of course, if you have the possibility to keep a key secure, the best option is to use a *keyed* hash function (an iterated salted version of HMAC for example), getting the benefits of both worlds...

Comment: Re:How Do Europeans Do It? (Score 1) 450

by L-One-L-One (#33339288) Attached to: Germany To Grant Privacy At the Workplace

The US has a lot to offer that Europe doesn't have, but when it comes to privacy, I think Europeans do have a strong lead:

* For a start Europeans have real privacy legislation (it's called Directive 95/46/EC). US Internet corporations will fight with big money against any similar initiative in the US.

* Each European Member State has a data protection authority that enforces privacy legislation, monitors the use of personal information and tries to educate the public. Some of these authorities even have inspection powers (see for example what they did over Streetview's interception of Wifi data). It has a little bureaucratic feel to it, but it works.

* Culturally in Europe, there's always a tendency to find a balance between each party’s legitimate interests and rights. Even in the workplace, people's right to privacy can't fully be obliterated by corporate needs.

The only caveat is that we are living more and more in a global world. My employer might be Chinese, my datacenters might be in the US, and my job might be in Europe. Which law applies then? That's the challenge!

Comment: It would be illegal in many EU coutries (Score 4, Interesting) 578

by L-One-L-One (#31215388) Attached to: Fingerprint Requirement For a Work-Study Job?

I know this will surprise many slashdot readers but using your fingerprint as described by the poster for the purpose of clocking you in and out of work would be illegal in many countries accross Europe (with the possible exception of the UK). In France, for example, you can actually get fined by the data protection authority for doing so.

It's true that most of these devices don't store an image of your fingerprint but rather a "template" : a description of some special features of your fingerprint. But that doesn't change the problem.

Indeed, many data proctection authorities accross the EU consider that biometrics pose sevreall security and data protection issues and must therefore be used with caution. Fingerprint biometrics are of special concern, in particular when the biometric data (templates) are stored in a central database. The big problem with fingerprints is that we leave them everywhere, on all objects we touch. Someone can pick up your fingerprint and test it against the templates inside the database. (Sounds crazy or technically impossible ? It's much easier than you think : i've tested it myself, that's part of my job). There are other issues whith fingerprint biometrics that I won't detail here.

In the end data protection authorities in the EU consider that the use of a central fingerprint database is excessive if your only objective is only clocking people in and out. Instead, they encourage the use of a smartcard to store the biometric data : you show your finger to the biometric reader and it gets compared with the data stored in the smartcard. This solution offers the same benefits in terms of security but you keep control of your biometric data.

Comment: Re:This is not a problem! (duh!) (Score 2, Interesting) 217

by L-One-L-One (#3510681) Attached to: Smart Cards Vulnerable to Photo-Flash Attacks?
I wouldn't be so sure ! The application you describe is very particular.

In practice, smartcards are often used as tamperproof devices to represent a third party, such as a bank. In France, for example, the credit card smart cards carry the bank's private key (for a Gilou/Quisquater RSA variant) as well as some additionnal secret information.
This information is not available for any reader but is used internaly for cryptographic computations.

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