Реализация на функцията за хеширане на MySQL

Първоначално се натъкнах на този въпрос в собственото си търсене на PHP реализация на двете функции за хеширане на пароли MySQL. Не успях да намеря никакви реализации, така че адаптирах моя собствен от изходния код на MySQL (sql/password.c). Следните са тествани и работят в 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 Defines 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 Defines 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

Дано и някой друг ще намери това за полезно :)