function user_check_password($password, $account) {
if (substr($account->pass, 0, 2) == 'U$') {
// This may be an updated password from user_update_7000(). Such hashes
// have 'U' added as the first character and need an extra md5().
$stored_hash = substr($account->pass, 1);
$password = md5($password);
}
else {
$stored_hash = $account->pass;
}
$type = substr($stored_hash, 0, 3);
switch ($type) {
case '$S$':
// A normal Drupal 7 password using sha512.
$hash = _password_crypt('sha512', $password, $stored_hash);
break;
case '$H$':
// phpBB3 uses "$H$" for the same thing as "$P$".
case '$P$':
// A phpass password generated using md5. This is an
// imported password or from an earlier Drupal version.
$hash = _password_crypt('md5', $password, $stored_hash);
break;
default:
return FALSE;
}
return ($hash && $stored_hash == $hash);
}
function _password_crypt($algo, $password, $setting) {
// The first 12 characters of an existing hash are its setting string.
$setting = substr($setting, 0, 12);
if ($setting[0] != '$' || $setting[2] != '$') {
return FALSE;
}
$count_log2 = _password_get_count_log2($setting);
// Hashes may be imported from elsewhere, so we allow != DRUPAL_HASH_COUNT
if ($count_log2 < DRUPAL_MIN_HASH_COUNT || $count_log2 > DRUPAL_MAX_HASH_COUNT) {
return FALSE;
}
$salt = substr($setting, 4, 8);
// Hashes must have an 8 character salt.
if (strlen($salt) != 8) {
return FALSE;
}
// Convert the base 2 logarithm into an integer.
$count = 1 << $count_log2;
// We rely on the hash() function being available in PHP 5.2+.
$hash = hash($algo, $salt . $password, TRUE);
do {
$hash = hash($algo, $hash . $password, TRUE);
} while (--$count);
$len = strlen($hash);
$output = $setting . _password_base64_encode($hash, $len);
// _password_base64_encode() of a 16 byte MD5 will always be 22 characters.
// _password_base64_encode() of a 64 byte sha512 will always be 86 characters.
$expected = 12 + ceil((8 * $len) / 6);
return (strlen($output) == $expected) ? substr($output, 0, DRUPAL_HASH_LENGTH) : FALSE;
}