(PHP 4 >= 4.0.4, PHP 5, PHP 7)
mhash_keygen_s2k — Generates a key
$hash
, string $password
, string $salt
, int $bytes
)
Generates a key according to the given hash
, using an user
provided password
.
This is the Salted S2K algorithm as specified in the OpenPGP document (» RFC 2440).
Keep in mind that user supplied passwords are not really suitable to be used as keys in cryptographic algorithms, since users normally choose keys they can write on keyboard. These passwords use only 6 to 7 bits per character (or less). It is highly recommended to use some kind of transformation (like this function) to the user supplied key.
hash
The hash ID used to create the key.
One of the MHASH_hashname
constants.
password
An user supplied password.
salt
Must be different and random enough for every key you generate in
order to create different keys. Because salt
must be known when you check the keys, it is a good idea to append
the key to it. Salt has a fixed length of 8 bytes and will be padded
with zeros if you supply less bytes.
bytes
The key length, in bytes.
Returns the generated key as a string, or FALSE
on error.