PBKDF2 is a key derivation and strengthening function, commonly used for password storage.

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LastPass One Time Recovery Passwords--How?

The LastPass password manager stores One Time Recovery Passwords locally in each browser you use the plugin with: http://helpdesk.lastpass.com/account-recovery/ My question is, how can you have more ...
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Improving Digest Authentication using PBKDF2

For a variety of reasons, I need to use digest authentication for a REST server that I have created. I have come up with an "improvement" that I believe strengthens the algorithm against MD5 attacks ...
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Client-Side Hashing to decrease value of password guessing heuristics

Yes, this is 'yet another client-side hashing' question. But, don't leave yet, I think there is some value here. I'd like to do something to mitigate the affect on the community as a whole when my ...
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How less secure is an encryption if we know something about the original data?

I have a number of files encrypted with a key derived from a password. In line with standard practice, I use a random salt and password and do many PBKDF2 iterations to obtain an encryption key and ...
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Key length and hash function in PBKDF2

On this page: http://www.ruby-doc.org/stdlib-2.0/libdoc/openssl/rdoc/OpenSSL/PKCS5.html they make a statement that strikes me as rather weird: Key Length Specifies the length in bytes of ...
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Is it safe to have the salt equal to IV?

If I'm using AES-256 CBC to encrypt, getting the 32 byte key using multiple iterations of the PBKDF2 function with a 16 byte salt, is it safe for me to let IV be equal to the salt? (Edit: The salt is ...
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Can the salt for PBKDF2 be a hash of the user-entered password?

I want to derive a key from a password in a client application that will be used as a master key that decrypts a data key. As far as I understand the salt should be private knowledge. Would it be ...
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BCrypt+SHA256 vs PBKDF2-SHA256

From this question, the OP posited taking a user's entered password, running it through BCrypt, then running that through SHA256 to produce a 256-bit password-derived key. (EDIT: To clarify, these two ...
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Maintain sensitive key between requests

EDIT: Reworked question. Previous version too poorly asked. On my website users write sensitive messages that must be kept secret. The entire user area is over SSL, so the communication between user ...
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How should I choose a difficulty factor for my password hashing function?

Assuming that I'm doing password hashing properly and using bcrypt, scrypt or PBKDF2, how should I go about choosing an appropriate difficulty factor? i.e rounds for bcrypt, iterations for PBKDF2 and ...
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With PBKDF2, what is an optimal Hash size in bytes? What about the size of the salt?

When creating a hash with PBKDF2, it allows the developer to choose the size of the hash. Is longer always better? Also, what about the size of the random salt? Should that be the same size as the ...
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Are there more modern password hashing methods than bcrypt and scrypt?

This question made me start thinking about password hashing again. I currently use bcrypt (specifically py-bcrypt). I've heard a lot about PBKDF2, and scrypt. What I'm wondering is if there are any ...
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Is there a table that compares hashing algorithms by speed, relatively (machine independent)

As far as I understood*, one of the major criteria when choosing a password / salt hashing algorithm is it's speed. To prevent brute force attacks, a slower algorithm is better (and also makes it more ...
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Challenging challenge: client-side password hashing and server-side password verification

We have a website where users need to log in to access privileged information. Obviously we are using SSL, but I also want to avoid plaintext passwords from accidently ending up in server logs, or ...
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Is there a better way to take advantage of current 'approved', 'proven', and memory/cpu-expensive algorithms while using salts and peppers?

I've read about the concepts presented in these two questions: Pre-hash password before applying bcrypt to avoid restricting password length Would it make sense to use Bcrypt and PBKDF2 together? I ...
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Recomended hash algorithm [duplicate]

Possible Duplicate: How to securely hash passwords? Do any security experts recommend bcrypt for password storage? What would you choose between: PBKDF2 SHA256 (270,000 iterations) ...
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What about combining pkdf2 with scrypt? [duplicate]

Possible Duplicate: Would it make sense to use Bcrypt and PBKDF2 together? How does the following password hashing scheme look to you? iterations1 = scrypt iterations required to spend ...
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Is PBKDF2 only SHA1 in C#?

I can't find a way of specifying the hashing algorithm used by the PBKDF2 (the Rfc2898DeriveBytes class) implementation in C# System.Security.Cryptography. It seems to be just SHA1. Am I missing ...
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Trying to understand password hashing

I am trying to get a grasp of password hashing. Back in the days it seemed so simple, just MD5(password + salt) and you are done. Then md5 was proven to have collisions so people started moving to ...
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Would it make sense to use Bcrypt and PBKDF2 together?

I've read various opinions about whether Bcrypt or PDBKF2 is a better key derivation hashing method. The answer seems to depend on a lot of complicated factors that are not easy to analyze. Would ...
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Does NIST really recommend PBKDF2 for password hashing?

We hesitated between BCrypt and PBKDF2 for password hashing. In many forums and blogs people say something like "In their Special Publication SP 800-132 NIST basically recommends using PBKDF2 for ...
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What's the advantage of using PBKDF2 vs SHA256 to generate an AES encryption key from a passphrase?

I'm looking at two comprable pieces of software which need to encrypt data on disk using a passphrase. One uses PBKDF2 to generate the encryption key from a passphrase, while the other uses two rounds ...
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Can a biometric device serve as a user based entropy source?

I am wondering if a biometric device can be used to generate some entropy or key material that would be stable across each authentication. The contrary would be for biometric devices to act like an ...