(PHP 5 >= 5.5.0)
hash_pbkdf2 — Generate a PBKDF2 key derivation of a supplied password
$algo
, string $password
, string $salt
, int $iterations
[, int $length
= 0
[, bool $raw_output
= false
]] )
algo
Name of selected hashing algorithm (i.e. md5, sha256, haval160,4, etc..) See hash_algos() for a list of supported algorithms.
password
The password to use for the derivation.
salt
The salt to use for the derivation.
iterations
The number of internal iterations to perform for the derivation.
length
The length of the derived key to output. If 0, the length of the supplied algorithm is used.
raw_output
When set to TRUE
, outputs raw binary data. FALSE
outputs lowercase
hexits.
Returns a string containing the derived key as lowercase hexits unless
raw_output
is set to true in which case the raw
binary representation of the derived key is returned.
An E_WARNING
will be raised if the algorithm is
unknown, the iterations
parameter is less than or
equal to 0, the length
is less
than 0 or the salt
is too long
(greater than INT_MAX
- 4).
Example #1 hash_pbkdf2() example, basic usage
<?php
$password = "password";
$salt = "salt";
$hash = hash_pbkdf2("sha256", $password, $salt, 1, 20);
echo $hash;
?>
以上例程会输出:
120fb6cffcf8b32c43e7
The PBKDF2 method can be used for hashing passwords for storage (it is
NIST approved for that use). However, it should be noted that
CRYPT_BLOWFISH
is better suited for password storage
and should be used instead via crypt().