Sam的程式筆記

public class IPMask {
    public enum Action {
        SINGLE, RANGE
    } 
    private Action action;//-- 動作

    private String ip;//-- 紀錄IP

    private int[] setip; //-- 原設定ip網段

    private int[] mask; //-- 設定mask


    public IPMask(String ipmask){
        String[] im = ipmask.split("/");
        this.ip = im[0];
        if(im.length == 1){
            //為單一IP

            action = Action.SINGLE;
        }else{
            //為網段

            action = Action.RANGE;
            String[] masks = im[1].split("\\.");
            for(int i=0;i<4;i++){
                if(this.mask==null) this.mask = new int[4];
                this.mask[i] = Integer.parseInt(masks[i]);
            }
            String[] ips = im[0].split("\\.");
            for(int i=0;i<ips.length;i++){
                if(this.setip==null) this.setip = new int[4];
                this.setip[i] = (Integer.parseInt(ips[i]) & this.mask[i]);
            }
        }
    }

    public boolean match(String ip){
        boolean allow = true;
        if(action == Action.SINGLE){
            if(!this.ip.equals(ip))
                allow = false;
        }else{
            String[] ips = ip.split("\\.");
            for(int i=0;i<4;i++){
                //兩個值做AND之後，如不是符合該網段則不在白名單內

                if((Integer.parseInt(ips[i])& mask[i])!= setip[i])
                    allow = false;
            }
        }
        return allow;
    }

    public static void main(String[] args) {
        IPMask ipmask = new IPMask("192.168.1.0/255.255.255.0");
        System.out.println(ipmask.match("192.168.1.60"));
        System.out.println(ipmask.match("192.168.2.60"));
        ipmask = new IPMask("192.168.1.60");
        System.out.println(ipmask.match("192.168.1.60"));
        System.out.println(ipmask.match("192.168.2.60"));
    }

public static void setIpmask(String[] ipmask) throws IllegalAccessException{
    String temp = null;
    String[] ipmaskarray = null;
    String[] tempIP = null;
    String[] tempMASK = null;
    ArrayList iplist = new ArrayList();
    for(int i=0;ipmask!=null&&i<ipmask.length;i++){
        temp = ipmask[i];
        if(temp==null || temp.trim().length()==0)
            continue;
        ipmaskarray = temp.split("/");
        if(ipmaskarray.length!=2)throw new IllegalAccessException("IP格式不合法"+"("+temp+")");
        tempIP = ipmaskarray[0].split("\\.");
        if(tempIP.length!=4)throw new IllegalAccessException("IP格式不合法"+"("+temp+")");
        for(int j=0;j<tempIP.length;j++){
            try {
                Integer.parseInt(tempIP[j]);
            } catch (NumberFormatException e) {
                throw new IllegalAccessException("IP數值非數字"+"("+temp+")");
            }
        }
        tempMASK = ipmaskarray[1].split("\\.");
        if(tempMASK.length!=4)throw new IllegalAccessException("遮罩格式不合法"+"("+temp+")");
        for(int j=0;j<tempMASK.length;j++){
            try {
                Integer.parseInt(tempMASK[j]);
            } catch (NumberFormatException e) {
                throw new IllegalAccessException("遮罩數值非數字"+"("+temp+")");
            }
        }
        iplist.add(temp);
    }
    setIptable("ipmask",iplist);
}

public static HashSet<String> ipset;
public static ArrayList<IPMask> masklist;
  
    public static boolean IPFilter(String ip){
        if((ipset==null || ipset.size()==0) && (masklist==null || masklist.size()==0)) return false;
        if(ipset.contains(ip)) return true;
        else{
            for(int i=0;i<masklist.size();i++){
                IPMask im = (IPMask)masklist.get(i);
                if(im.match(ip)) return true;
            }
            return false;
        }
    }