WPA2 password

i want to write php script to convert ssid and WPA passphrase to hex ,how can i convert ?
for example
ESSID AndroidAP passphrase 12345678
hex =2425C701C802036D2298E802F2DD062DC2F91BC2CE8A5EDA7FC2F2B3F396EA1E
i find in google function
Key = PBKDF2(passphrase, ssid, 4096, 256)

 

There is a PHP function you can look @:

http://php.net/manual/en/function.hash-pbkdf2.php (php >= 5.5)

Additionally the logic (which you can program) is also laid out here:

http://www.ietf.org/rfc/rfc2898.txt

Above PHP link also contains such implementations if you have done 5.5.