I originally stumbled across this question in my own search for a PHP implementation of the two MySQL password hashing functions. I was unable to find any implementations, so I adapted my own from the MySQL source code (sql/password.c). The following are tested and working in PHP 5.2:
// The following is free for any use provided credit is given where due.
// This code comes with NO WARRANTY of any kind, including any implied warranty.
/**
* MySQL "OLD_PASSWORD()" AKA MySQL323 HASH FUNCTION
* This is the password hashing function used in MySQL prior to version 4.1.1
* By Rev. Dustin Fineout 10/9/2009 9:12:16 AM
**/
function mysql_old_password_hash($input, $hex = true)
{
$nr = 1345345333; $add = 7; $nr2 = 0x12345671; $tmp = null;
$inlen = strlen($input);
for ($i = 0; $i < $inlen; $i++) {
$byte = substr($input, $i, 1);
if ($byte == ' ' || $byte == "\t") continue;
$tmp = ord($byte);
$nr ^= ((($nr & 63) + $add) * $tmp) + (($nr << 8) & 0xFFFFFFFF);
$nr2 += (($nr2 << 8) & 0xFFFFFFFF) ^ $nr;
$add += $tmp;
}
$out_a = $nr & ((1 << 31) - 1);
$out_b = $nr2 & ((1 << 31) - 1);
$output = sprintf("%08x%08x", $out_a, $out_b);
if ($hex) return $output;
return hex_hash_to_bin($output);
} //END function mysql_old_password_hash
/**
* MySQL "PASSWORD()" AKA MySQLSHA1 HASH FUNCTION
* This is the password hashing function used in MySQL since version 4.1.1
* By Rev. Dustin Fineout 10/9/2009 9:36:20 AM
**/
function mysql_password_hash($input, $hex = true)
{
$sha1_stage1 = sha1($input, true);
$output = sha1($sha1_stage1, !$hex);
return $output;
} //END function mysql_password_hash
/**
* Computes each hexidecimal pair into the corresponding binary octet.
* Similar to mysql hex2octet function.
**/
function hex_hash_to_bin($hex)
{
$bin = "";
$len = strlen($hex);
for ($i = 0; $i < $len; $i += 2) {
$byte_hex = substr($hex, $i, 2);
$byte_dec = hexdec($byte_hex);
$byte_char = chr($byte_dec);
$bin .= $byte_char;
}
return $bin;
} //END function hex_hash_to_bin
Hopefully someone else will find this useful as well :)