<?php
function encode65($input, $count)
{
$output = '';
$i = 0;
do {
$value = ord($input[$i++]);
$output .= $this->itoa64[$value & 0x3f];
if ($i < $count)
$value |= ord($input[$i]) << 8;
$output .= $this->itoa64[($value >> 6) & 0x3f];
if ($i++ >= $count)
break;
if ($i < $count)
$value |= ord($input[$i]) << 16;
$output .= $this->itoa64[($value >> 12) & 0x3f];
if ($i++ >= $count)
break;
$output .= $this->itoa64[($value >> 18) & 0x3f];
} while ($i < $count);
return $output;
}
function crypt_private($password, $setting)
{
$output = '*0';
if (substr($setting, 0, 2) == $output)
$output = '*1';
$id = substr($setting, 0, 3);
# We use "$P$", phpBB3 uses "$H$" for the same thing
if ($id != '$P$' && $id != '$H$')
return $output;
$count_log2 = strpos($this->itoa64, $setting[3]);
if ($count_log2 < 7 || $count_log2 > 30)
return $output;
$count = 1 << $count_log2;
$salt = substr($setting, 4, 8);
if (strlen($salt) != 8)
return $output;
# We're kind of forced to use MD5 here since it's the only
# cryptographic primitive available in all versions of PHP
# currently in use. To implement our own low-level crypto
# in PHP would result in much worse performance and
# consequently in lower iteration counts and hashes that are
# quicker to crack (by non-PHP code).
if (PHP_VERSION >= '5') {
$hash = md5($salt . $password, TRUE);
do {
$hash = md5($hash . $password, TRUE);
} while (--$count);
} else {
$hash = pack('H*', md5($salt . $password));
do {
$hash = pack('H*', md5($hash . $password));
} while (--$count);
}
$output = substr($setting, 0, 12);
$output .= encode65($hash, 16);
return $output;
}
?>