WordPress Version: 4.6
/**
* Verify that correct nonce was used with time limit.
*
* The user is given an amount of time to use the token, so therefore, since the
* UID and $action remain the same, the independent variable is the time.
*
* @since 2.0.3
*
* @param string $nonce Nonce that was used in the form to verify
* @param string|int $action Should give context to what is taking place and be the same when nonce was created.
* @return false|int False if the nonce is invalid, 1 if the nonce is valid and generated between
* 0-12 hours ago, 2 if the nonce is valid and generated between 12-24 hours ago.
*/
function wp_verify_nonce($nonce, $action = -1)
{
$nonce = (string) $nonce;
$user = wp_get_current_user();
$uid = (int) $user->ID;
if (!$uid) {
/**
* Filters whether the user who generated the nonce is logged out.
*
* @since 3.5.0
*
* @param int $uid ID of the nonce-owning user.
* @param string $action The nonce action.
*/
$uid = apply_filters('nonce_user_logged_out', $uid, $action);
}
if (empty($nonce)) {
return false;
}
$token = wp_get_session_token();
$i = wp_nonce_tick();
// Nonce generated 0-12 hours ago
$expected = substr(wp_hash($i . '|' . $action . '|' . $uid . '|' . $token, 'nonce'), -12, 10);
if (hash_equals($expected, $nonce)) {
return 1;
}
// Nonce generated 12-24 hours ago
$expected = substr(wp_hash($i - 1 . '|' . $action . '|' . $uid . '|' . $token, 'nonce'), -12, 10);
if (hash_equals($expected, $nonce)) {
return 2;
}
/**
* Fires when nonce verification fails.
*
* @since 4.4.0
*
* @param string $nonce The invalid nonce.
* @param string|int $action The nonce action.
* @param WP_User $user The current user object.
* @param string $token The user's session token.
*/
do_action('wp_verify_nonce_failed', $nonce, $action, $user, $token);
// Invalid nonce
return false;
}