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What is a pepper in hashing?
In cryptography, a pepper is a secret added to an input such as a password during hashing with a cryptographic hash function. It is like a salt in that it is a randomized value that is added to a password hash, and it is similar to an encryption key in that it should be kept secret.
Does Bcrypt use pepper?
The way bcrypt (and other password hashing algorithms) were designed is to work with a salt. The concept of a pepper was never introduced. This may seem like a triviality, but it’s not.
What is salting in hash?
Salting hashes sounds like one of the steps of a hash browns recipe, but in cryptography, the expression refers to adding random data to the input of a hash function to guarantee a unique output, the hash, even when the inputs are the same.
What is pepper in password?
What is a Pepper? Like a salt, a “pepper” is also a random string of data that is appended to a password before hashing. However, unlike a salt, peppers are kept secret. They are typically stored separately from the user information or stored in a site’s source code.
Why do you put pepper in a password hash?
So really, a pepper would be a way of slowing an attacker down for a trivial amount of overhead time. They wouldn’t have to brute force the password + salt + pepper, as intended, only the pepper. The above is a form of chosen plaintext attack.
Can You hash two passwords with the same salt?
Because of the password specific salt you even can’t find out if two passwords in the database are the same or not. The reason is that hash ($pepper . $salt . $password) effectively build a pseudo random function with $pepper as key and $salt.$password as input (for sane hash candidates like PBKDF2 with SHA*, bcrypt or scrypt).
How are salt and pepper used in password security?
The paper on the invention of salting and iterations, for Unix passwords ( Password Security: A Case History, Morris & Thompson, 1978 ), also described the equivalent of a pepper: The first eight characters of the user’s password are used as a key for the DES; then the algorithm is used to encrypt a constant.
Which is the most important aspect of password hashing?
The most important aspect of every password hashing scheme is that hash is a slow cryptographically secure hash function, see https://security.stackexchange.com/a/31846/10727 for more background knowledge.