A key derivation function (KDF) is a function used to derive an encryption key from a password.
Questions tagged [kdf]
35 questions
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Argon2id key derivation rate calculation question
Just wanted to know if this was an accurate way of determining how long it would take someone with an 8GB GPU to derive 1 million keys using some assumed parameters below:
Time per derivation...........: 3.5 seconds
Memory required per derivation:…
Guy Bartkus
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Most secure algorithms for KDF and Public Key Encryption
I'm developing an application which will need to derive a private/public key pair from a user provided password, and then use the public key to encrypt some text (up to 1000 characters in length) such that it can only be decrypted by the paired…
vikarjramun
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How to encrypt user data in app using Google Sign-In
I am currently writing an application which needs to store user data encrypted in the database. One of the requirements is that some of the data stored in the database needs to be encrypted in a way that we (the database administrators, with full…
vikarjramun
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Deriving 2 keys from user password - one for login - one for encryption?
Context
We have a browser-based client-server application. The client registers with email and password. The password is enforced to some guidelines.
Problem
The User needs an encrypted vault on the server to store cryptographic keys in such a way…
Dachstein
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How to find default S2K parameters in GPG
How can I find the default string-to-key parameters in GPG? I am using it in Tails.
Yang88
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How can I find the default KDF for my version of GPG?
I am trying to find the default KDF for my version of gpg:
gpg (GnuPG) 2.2.6
libgcrypt 1.8.2
Does anyone know how?
Patriot
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Encryption for a system supporting only basic cryptographic functions
I am working on an encryption method between a server and multiple clients. The client hardware only supports basic encryption algorithms (Currently Aes 128-bits and HmacSha1). The hardware is too simple to support TLS/SSL. I have read about…
david
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One Input Two Hashes
Suppose I have some password x, and two different hash functions h1 and h2. I can then compute the hash y1 = h1(x) and y2 = h2(x).
Is there any sort of vulnerability in this case? More specifically, is it possible to get y1 from y2 and vise versa?…
nehcsivart
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Understanding the application of hashes, HMACs, and KDFs
I think that I understand the right application cases for the following crypto functions, but I'd like to confirm my understanding and also propagate the safe use of crypto throughout the intertubes. Cryptography and its implementation are often…
Naftuli Kay
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KDF vs hash function in loop for hashing password
I'm trying to grasp which benefit can KDF like PBKDF2, scrypt and bcrypt (I know that bcrypt is technically not KDF) may bring over hashing in loop like sha256sum(sha256sum(sha256sum.....(salt + master password))) - N times, where N equals to some…
Ghost Rider
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Key derivation for password manager backup?
Backing up your password manager is a good idea in case your house burns down, but where do you store the password to the off-site backup?
Remembering the master password is easy, but re-using the master password directly for my off-site backup is a…
Fax
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Verify password before decrypting data
I need to verify a password before decrypting the data. My encrypted data is too big and waiting to see if the authentication tag is correct is out of the question. I’m using Argon2id as my KDF. My question is, can I hash the derived key with SHA256…
Bernardo1r
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SCrypt's goal and the role its salt plays
Am I right in stating that SCrypt as an algorithm is useful where many passwords are stored in a database, but not against one specific encryption key derived from one password of one user?
For example, let there be a password, a salt, and…
Neev Penkar
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Use PBKDF2 for both authentication and decryption on NodeJS
I am using PBKDF2 on NodeJS to authenticate a user who submits username & password. To do this, when the user first registers, I generate a salt, I use 200000 iterations, I specify a key length of 32 bytes, and I use sha256 as the digest method.…
vrtjason
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TLS 1.3 HKDF-Expand references to Hello messages
I am looking into TLS 1.3 implementations and am a little confused about what is being referenced in the HKDF functions. Specifically the last argument in the Dervice_Secret wrapper function. From RFC 8446:
PSK -> = Early Secret
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Liam Kelly
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