(PHP 4 >= 4.0.4)
mhash_keygen_s2k -- Generates a key
Description
string mhash_keygen_s2k (int hash, string password, string salt, int
bytes)
mhash_keygen_s2k() generates a key that is bytes long, from a user
given password. This is the Salted S2K algorithm as specified in the OpenPGP document (RFC 2440).
That algorithm will use the specified hash algorithm to create the key. The
salt must be different and random enough for every key you generate in order to create
different keys. That salt must be known when you check the keys, thus 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. 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 tranformation (like this function) to the user supplied key.
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