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Is a password hash always the same?
As we have learned with the overview of password hashing, the hashed equivalent of the password is the same each time. It means that using a known or commonly used weak password is dangerous no matter the hashing algorithm used.
Why does bcrypt create different hashes?
Because bcrypt generates a different salt every time, the hash is always different meaning I can no longer use the generated hash to identify the user’s data in the database, unless I force the app to use the same salt each time it generates a bcrypt hash.
Can 2 different passwords have the same hash?
This question already has answers here: When hashing passwords, two passwords can produce the same hash, so if a user inputs someone else’s username but his own password, there is a possibility that he will be able to login to that other account.
Why does PHP password _ hash ( ) generate different?
The hash will be identical and a user is able to login. If you want that your hash stays always the same you need to deliver an own salt with the option salt to PASSWORD_BCRYPT. This is not considered as secure if you are not knowing what you are doing. So i would prefer the automatically generated salt.
How does password _ hash / password _ verify work?
Therefore, all information that’s needed to verify the hash is included in it. This allows the verify function to verify the hash without needing separate storage for the salt or algorithm information. This function is safe against timing attacks. What is going on?
How to generate salt for password bcrypt in PHP?
Supported options for PASSWORD_BCRYPT : salt ( string) – to manually provide a salt to use when hashing the password. Note that this will override and prevent a salt from being automatically generated. If omitted, a random salt will be generated by password_hash () for each password hashed. This is the intended mode of operation.
How is a random salt generated in PHP?
If omitted, a random salt will be generated by password_hash () for each password hashed. This is the intended mode of operation. The salt option has been deprecated as of PHP 7.0.0. It is now preferred to simply use the salt that is generated by default.