java --IP地址段的过滤
IP地址段的过滤
????????昨天接到领导指示，要对地市的ＩＰ地址进行过滤，晕了，过滤啥呀，不过想归想，那还得做不是，呵呵
开始想在服务器<Tomcat>上整一下呢，仔细一看不行，附Tomcat过滤ＩＰ方法：
限制ip，限制主机访问:
如果想禁止指定的ip或者主机名来拒绝某些机器访问，或者指定某些机器来访问。
也支持分别按Engine, Host, or Context,进行以下配置：
<Context path="/examples" ...> ...
<Valve className="org.apache.catalina.valves.RemoteHostValve"
allow="*.mycompany.com,www.yourcompany.com"/>
<Valve className="org.apache.catalina.valves.RemoteAddrValve"
deny="192.168.1.*"/>
</Context>
参考：
http://jakarta.apache.org/tomcat/tomcat-5.0-doc/config/context.html
没辙，继续．．．
因为要过滤的ＩＰ有七十二组<(58.87.96.0????58.57.121.255),(219.147.0.0????219.147.0.211)>想到用正则表达式，因为本人对正则表达式这东西，实在不精，呵呵，也就没敢用，呵呵
最终在于朋友交流后，采取如下形式解决的：
一、新建一xml配置文件，将要过滤的IP段写入；
二、新建一Filter，完成过滤要求
代码如下所示：
IP.XML
<?xml version="1.0" encoding="UTF-8"?>
<root id="allow">
?? <group>????
????<start>122.6.192.0</start>
????<end>122.6.255.255</end>
?? </group>
?? <group>????
????<start>219.146.208.0</start>
????<end>219.146.215.255</end>
?? </group>
?? <group>????
????<start>222.174.224.0</start>
????<end>222.174.255.255</end>
?? </group>
</root>
Filter如下所示：
import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;
import javax.xml.parsers.*;
public class FilterServlet????extends HttpServlet????implements Filter {
??
??private Document doc=null;
??private FilterConfig filterConfig;
??//Handle the passed-in FilterConfig
??private String encoding = "GBK";
??
??public void init(FilterConfig filterConfig) {
????this.filterConfig = filterConfig;
??}
??//Process the request/response pair
??public void doFilter(ServletRequest request, ServletResponse response,
?????????????????????? FilterChain filterChain) {
??
?? HttpServletResponse httpResp = null;
?? HttpServletRequest httpReq = null;
????try {
??????String reqip = request.getRemoteHost();
??????if(null != reqip){??????
??????????reqip = reqip.replace('.','_');
??????}
??????String[] temp = reqip.split("_");
??????int[] ip = new int[temp.length];
??????
??????for(int i=0;i<temp.length;i++){??????
??????????ip[i] = new Integer(temp[i]).intValue();
??????}
??????if (response instanceof HttpServletResponse) {
??????
?????? httpReq = (HttpServletRequest)request;
?????? httpResp = (HttpServletResponse)response;
??????if(!viewXml(httpReq.getRealPath("/")+"/WEB-INF/ip.xml",ip)){
??????
?????? httpResp.sendRedirect(" http://welcome.sd.vnet.cn/ ");
??????}
??????filterChain.doFilter(request, response);
????}
????}
????catch (ServletException sx) {
???? filterConfig.getServletContext().log(sx.getMessage());
????}
????catch (IOException iox) {
??????filterConfig.getServletContext().log(iox.getMessage());
????}catch(Exception e){
????
???? filterConfig.getServletContext().log(e.getMessage());
????}
??}
??
??/**
?? * 验证请求ＩＰ是否符合要求
?? * @param xmlFile
?? * @return
?? * @throws Exception
?? */
??public boolean viewXml(String xmlFile,int[] ip) throws Exception {
??
?? int[] test = ip;
?? boolean flag = true;
?? DocumentBuilderFactory dbf=DocumentBuilderFactory.newInstance();
?? DocumentBuilder db=dbf.newDocumentBuilder();??
?? doc=db.parse(new File(xmlFile));
?? Element root = doc.getDocumentElement();
??????NodeList list = root.getElementsByTagName("group");
??????for (int i=0; i < list.getLength() ; i++) {
????????Element element = (Element)list.item(i);
????????NodeList titleid = element.getElementsByTagName("start");
????????Element idElement = (Element)titleid.item(0);
????????String ip1 = idElement.getFirstChild().getNodeValue();??????
????????ip1 = ip1.replace('.','_');
????????String[] ip1s = ip1.trim().split("_");
????????Integer[] ipl1 = new Integer[ip1s.length];
????????for(int a=0;a<ip1s.length;a++){
??????????????????ipl1[a] = new Integer(ip1s[a]);
????????}
????????
????????NodeList titleList = element.getElementsByTagName("end");
????????Element titleElement = (Element)titleList.item(0);
????????String ip2 = titleElement.getFirstChild().getNodeValue();
????????ip2 = ip2.replace('.','_');
????????String[] ip2s = ip2.trim().split("_");
????????Integer[] ipl2 = new Integer[ip2s.length];
????????for(int b=0;b<ip2s.length;b++){????????
????????????ipl2[b] = new Integer(ip2s[b]);
????????}
????????
????????long test_value = test[0]*255*255*255+test[1]*255*255+test[2]*255+test[3];
????????long ip1_value = ipl1[0]*255*255*255+ipl1[1]*255*255+ipl1[2]*255+ipl1[3];
????????long ip2_value = ipl2[0]*255*255*255+ipl2[1]*255*255+ipl2[2]*255+ipl2[3];
????????
????????if(test_value >= ip1_value && test_value <= ip2_value){????????
????????????return true;
????????}
????????
??????}??????
??????return false;
??}
??public void destroy() {
????filterConfig = null;
????encoding = null;
??}
}
WEB.XML如下：
<filter>
??<filter-name>filterservlet</filter-name>
??<filter-class>com.lvke.web.qcbst.util.common.FilterServlet</filter-class>
</filter>
<filter-mapping>
?? <filter-name>filterservlet</filter-name>
??<url-pattern>/*</url-pattern>
</filter-mapping>
希望能给用到的朋友减少一下负担，呵呵
