first commit

hrmsEjb/org/apache/struts/util/TokenProcessor.java

@@ -0,0 +1,75 @@
+package org.apache.struts.util;
+
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpSession;
+
+public class TokenProcessor {
+  private static TokenProcessor instance = new TokenProcessor();
+  
+  public static TokenProcessor getInstance() {
+    return instance;
+  }
+  
+  public synchronized boolean isTokenValid(HttpServletRequest request) {
+    return isTokenValid(request, false);
+  }
+  
+  public synchronized boolean isTokenValid(HttpServletRequest request, boolean reset) {
+    HttpSession session = request.getSession(false);
+    if (session == null)
+      return false; 
+    String saved = (String)session.getAttribute("org.apache.struts.action.TOKEN");
+    if (saved == null)
+      return false; 
+    if (reset)
+      resetToken(request); 
+    String token = request.getParameter("org.apache.struts.taglib.html.TOKEN");
+    if (token == null)
+      return false; 
+    return saved.equals(token);
+  }
+  
+  public synchronized void resetToken(HttpServletRequest request) {
+    HttpSession session = request.getSession(false);
+    if (session == null)
+      return; 
+    session.removeAttribute("org.apache.struts.action.TOKEN");
+  }
+  
+  public synchronized void saveToken(HttpServletRequest request) {
+    HttpSession session = request.getSession();
+    String token = generateToken(request);
+    if (token != null)
+      session.setAttribute("org.apache.struts.action.TOKEN", token); 
+  }
+  
+  public String generateToken(HttpServletRequest request) {
+    HttpSession session = request.getSession();
+    try {
+      byte[] id = session.getId().getBytes();
+      byte[] now = (new Long(System.currentTimeMillis())).toString().getBytes();
+      MessageDigest md = MessageDigest.getInstance("MD5");
+      md.update(id);
+      md.update(now);
+      return toHex(md.digest());
+    } catch (IllegalStateException e) {
+      return null;
+    } catch (NoSuchAlgorithmException e) {
+      return null;
+    } 
+  }
+  
+  public String toHex(byte[] buffer) {
+    StringBuffer sb = new StringBuffer();
+    String s = null;
+    for (int i = 0; i < buffer.length; i++) {
+      s = Integer.toHexString(buffer[i] & 0xFF);
+      if (s.length() < 2)
+        sb.append('0'); 
+      sb.append(s);
+    } 
+    return sb.toString();
+  }
+}