Java Servlet for department secure pull service


package in.cdac.hash;

import java.io.IOException;
import java.io.PrintWriter;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
* Servlet implementation class PullSecureServlet
*/
public class PullSecureServlet extends HttpServlet {
private static final long serialVersionUID = 1L;

/**
* @see HttpServlet#HttpServlet()
*/
public PullSecureServlet() {
super();
// TODO Auto-generated constructor stub
}

/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse
* response)
*/
protected void doGet(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
}

/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse
* response)
*/
protected void doPost(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
String finalresponse = "not Authenticated";
PrintWriter out = response.getWriter();
/*
* get the random number provided to department at the time of
* registration.
*/
String RandomNumber = "here get the random number provided to department at the time of registration.";
String MobileNo = ESAPI.encoder().encodeForHTML(request.getParameter("mobileNumber"));
String TimeStamp = ESAPI.encoder().encodeForHTML(request.getParameter("timeStamp"));
String OperatorName = ESAPI.encoder().encodeForHTML(request.getParameter("operatorName"));
String Areacode = ESAPI.encoder().encodeForHTML(request.getParameter("areaCode"));
String Message = ESAPI.encoder().encodeForHTML(request.getParameter("message"));
String recievedHash = ESAPI.encoder().encodeForHTML(request.getParameter("hash"));

System.out.println("MobileNo==" + MobileNo + "\n" + "TimeStamp=="
+ TimeStamp + "\n" + "OperatorName==" + OperatorName + "\n"
+ "AreaCode==" + Areacode + "\n" + "Message==" + Message + "\n"
+ "hash==" + recievedHash);

String hashValue = hashGenerate(TimeStamp, Message, MobileNo,
RandomNumber);
System.out.println("final generated hash is ::;" + hashValue);
if (hashValue.equals(recievedHash)) {
System.out
.println("both hash are equal and request is from authenticated source.");
finalresponse="if Authenticated provide your response";
} else {
System.out.println("both hash are different");
finalresponse="if not Authenticated provide your response";
}

out.println(finalresponse);
}

protected String hashGenerate(String timestamp, String message,
String mobileNo, String randomNumber) {
StringBuffer hexString = null;
StringBuffer finalString = new StringBuffer();
finalString.append(mobileNo.trim()).append(timestamp.trim())
.append(message.trim()).append(randomNumber.trim());
System.out.println("final string is ::" + finalString.toString());
String hashGen = finalString.toString();

MessageDigest md;
try {
md = MessageDigest.getInstance("SHA-512");

md.update(hashGen.getBytes());

byte byteData[] = md.digest();

// convert the byte to hex format method 1
StringBuffer sb = new StringBuffer();
for (int i = 0; i < byteData.length; i++) {
sb.append(Integer.toString((byteData[i] & 0xff) + 0x100, 16)
.substring(1));
}

//System.out.println("Hex format : " + sb.toString());

// convert the byte to hex format method 2
hexString = new StringBuffer();
for (int i = 0; i < byteData.length; i++) {
String hex = Integer.toHexString(0xff & byteData[i]);
if (hex.length() == 1)
hexString.append('0');
hexString.append(hex);
}

//System.out.println("Hex format : " + hexString.toString());
} catch (NoSuchAlgorithmException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return hexString.toString();

}

}