验证码防刷处理

//防刷处理
$access_count=accessCountLimit();
if ($access_count) {
    die;
}

/**
 * 频繁提交总控制,30分钟20次
 */
function accessCountLimit($limit=30, $time=1800)
{
    $result=false;
    if (!isset($_SESSION)) {
        session_start();
    }
    if (!isset($_SESSION['access_count'])) {
        $_SESSION['access_count']=1;
    }
    if (!isset($_SESSION['last_access']) || (time()-$_SESSION['last_access'])>$time) {
        $_SESSION['last_access']=time();
        $_SESSION['access_count']=1;
    }
    $_SESSION['access_count']=(int)$_SESSION['access_count']+1;
    if ((int)$_SESSION['access_count']>$limit || accessCountLimitPerMinute()) {
        $result=true;
    }
    return $result; 
}

/**
 * 频繁提交 1分钟4次
 */
function accessCountLimitPerMinute($limit=10, $time=60)
{
    $result=false;
    if (!isset($_SESSION)) {
        session_start();
    }
    if (!isset($_SESSION['access_count_minute'])) {
        $_SESSION['access_count_minute']=1;
    }
    if (!isset($_SESSION['last_access_minute']) || (time()-$_SESSION['last_access_minute'])>$time) {
        $_SESSION['last_access_minute']=time();
        $_SESSION['access_count_minute']=1;
    }
    $_SESSION['access_count_minute']=(int)$_SESSION['access_count_minute']+1;
    if ((int)$_SESSION['access_count_minute']>$limit) {
        $result=true;
    }
    return $result;
}