实现RSA时，发现后台生成的公钥转化为16进制传到前端时出错

Choee-z 2016-11-08 12:19:09

后台生成公私钥后需要转化成16进制传到前端
但是原来的bigint转化的16进制数不等于原数值

前端公钥解密使用的是网上用的多的Barrett.js，BigInt.js和RSA.js应该没什么问题

前端代码：



<%@ page language="java" contentType="text/html; charset=UTF-8"

	pageEncoding="UTF-8"%>

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">

<html>

<%

	String path = request.getContextPath();

	String basePath = request.getScheme() + "://" + request.getServerName() + ":" + request.getServerPort()

			+ path + "/";

%>

<head>

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

<script type='text/javascript' src='scripts/jquery-1.9.1.min.js'></script>

<script type='text/javascript' src='scripts/Barrett.js'></script>

<script type='text/javascript' src='scripts/BigInt.js'></script>

<script type='text/javascript' src='scripts/RSA.js'></script>

<title>Insert title here</title>

</head>

<body>

<script type="text/javascript">

$(function(){

	$("#btn").click(function(){

		$.get("<%=path%>/rsaMethod", function(data) {

			var arr = eval(data);

			$("#Modulus").val(arr[0]);

			$("#PublicExponent").val(arr[1]);

			alert(data);

		});

		$("form").css({

			"display" : "block"

		});

	});

	

 	$("#submitbtn").click(function() {

		var name=$("#name").val();

		var password=$("#password").val();

		var rsa_e = $("#PublicExponent").val();

		var rsa_m = $("#Modulus").val();

		setMaxDigits(130);

		var key = new RSAKeyPair(rsa_e,'', rsa_m,1024);

	    password = encryptedString(key, encodeURIComponent(password)); 

	    alert(password);

	    var arr={};

	    arr.name=name;

	    arr.password=password;

	    $.post("<%=path%>/rsaMethod",arr,function(data){

	    	alert(data);

	    });

	}); 

})

</script>

	<button id="btn">click</button>

	<form action="" method="post" style="display: none;">

		name:<input type="text" id="name"><br>

		password:<input type="text" id="password"> 

		<input type="hidden" id="Modulus">

		<input type="hidden" id="PublicExponent">

		<button id="submitbtn">submit</button>

	</form>

</body>

</html>

后台servlet





@WebServlet("/rsaMethod")

public class rsaMethod extends HttpServlet {

	private static final long serialVersionUID = 1L;



	private static KeyPairGenerator keypairgenerator;

	private static KeyPair keypair;

	private static RSAPublicKey rsapublicKey;

	private static RSAPrivateKey rsaprivateKey;

	

	private String message = "123";



	public rsaMethod() throws NoSuchAlgorithmException {

		super();

		keypairgenerator = KeyPairGenerator.getInstance("RSA");

		keypairgenerator.initialize(1024);

		keypair = keypairgenerator.generateKeyPair();

		rsapublicKey = (RSAPublicKey) keypair.getPublic();

		rsaprivateKey = (RSAPrivateKey) keypair.getPrivate();

	}



	/*

	 * // rsa加密 

	 * public byte[] Encode() throws Exception { 

	 * X509EncodedKeySpec x509encodedkeyspec = new X509EncodedKeySpec(rsapublicKey.getEncoded());

	 * KeyFactory keyfactory = KeyFactory.getInstance("RSA"); 

	 * PublicKey publickey = keyfactory.generatePublic(x509encodedkeyspec);

	 * System.out.println(publickey);

	 * 

	 * Cipher cipher = Cipher.getInstance("RSA");

	 * cipher.init(cipher.ENCRYPT_MODE, publickey); 

	 * byte[] result = cipher.doFinal(message.getBytes());

	 * System.out.println(Base64.getEncoder().encodeToString(result)); 

	 * return result;

	 * 

	 * }

	 * 

	 * // rsa解密

	 * public void Decode(byte[] arr) throws Exception {

	 * PKCS8EncodedKeySpec pkcs8encodedkeyspec = new PKCS8EncodedKeySpec(rsaprivateKey.getEncoded()); 

	 * KeyFactory keyfactory =KeyFactory.getInstance("RSA"); 

	 * PrivateKey privatekey = keyfactory.generatePrivate(pkcs8encodedkeyspec);

	 * 

	 * Cipher cipher = Cipher.getInstance("RSA");

	 * cipher.init(cipher.DECRYPT_MODE, privatekey); 

	 * byte[] result = cipher.doFinal(arr); 

	 * System.out.println(new String(result));

	 * }

	 */



	// 获取公钥

	public PublicKey getPublickey() throws Exception {

		X509EncodedKeySpec x509encodedkeyspec = new X509EncodedKeySpec(rsapublicKey.getEncoded());

		KeyFactory keyfactory = KeyFactory.getInstance("RSA");

		PublicKey publickey = keyfactory.generatePublic(x509encodedkeyspec);

		

		System.out.println(((RSAPublicKey)publickey).getPublicExponent());

		

		return publickey;

	}



	// 获取私钥

	public PrivateKey getPrivatekey() throws Exception {

		PKCS8EncodedKeySpec pkcs8encodedkeyspec = new PKCS8EncodedKeySpec(rsaprivateKey.getEncoded());

		KeyFactory keyfactory = KeyFactory.getInstance("RSA");

		PrivateKey privatekey = keyfactory.generatePrivate(pkcs8encodedkeyspec);

		

		System.out.println(((RSAPrivateKey)privatekey).getPrivateExponent());

		

		return privatekey;

	}



	// 判断钥匙文件是否存在，是否有内容

	public void JudgeNone(String path) throws Exception {

		File file = new File(path);

		if (!file.exists()) {

			file.createNewFile();

		}

		if (file.length() == 0) {

			outputkeyTofile(file);

		}

	}



	// 向文件中写入公私钥

	public void outputkeyTofile(File file) throws Exception {

		PublicKey publickey = getPublickey();

		PrivateKey privatekey = getPrivatekey();



		System.out.println(publickey);

		System.out.println(privatekey);



		OutputStream os = new FileOutputStream(file);

		ObjectOutputStream oos = new ObjectOutputStream(os);

		oos.writeObject(publickey);

		oos.writeObject(privatekey);

		oos.writeObject(null);

		oos.close();

	}

	

	//文件中读取公钥

	public PublicKey getPubkeyfromFile(String pathname) throws Exception{

		InputStream ins=new FileInputStream(pathname);

		ObjectInputStream oins=new ObjectInputStream(ins);

		Object obj=oins.readObject();

		oins.close();

		ins.close();

		return (PublicKey)obj;

	}

	

	//公钥中读取modulus和publicPublicExponent

	public JSONArray getpublicKey(String pathname) throws Exception {

		JSONArray arr = new JSONArray();

		PublicKey publickey = getPubkeyfromFile(pathname);

		arr.add(((RSAPublicKey) publickey).getModulus().toString(16));

		

		System.out.println("原来："+((RSAPublicKey) publickey).getModulus());

		System.out.println("16新的："+((RSAPublicKey) publickey).getModulus().toString(16));

		

		arr.add(((RSAPublicKey) publickey).getPublicExponent().toString(16));

		return arr;

	}

	

	//从文件中读取私钥

	public PrivateKey getPrikeyfromFile(String pathname) throws Exception{

		InputStream ins=new FileInputStream(pathname);

		ObjectInputStream oins=new ObjectInputStream(ins);

		Object obj=oins.readObject();

		obj=oins.readObject();

		oins.close();

		ins.close();

		return (PrivateKey)obj;

	}

	

	//私钥解密

	public String Decode(String pathname,String value) throws Exception{

		PrivateKey privatekey=getPrikeyfromFile(pathname);



		Cipher cipher = Cipher.getInstance("RSA");

		cipher.init(cipher.DECRYPT_MODE, privatekey); 

		byte[] result = cipher.doFinal(value.getBytes()); 

		System.out.println(new String(result));

		

		return new String(result);

	}

	

	protected void doGet(HttpServletRequest request, HttpServletResponse response)

			throws ServletException, IOException {

		String pathname = request.getSession().getServletContext().getRealPath("/key.txt");

		try {

			JudgeNone(pathname);

			JSONArray arr = getpublicKey(pathname);

			response.getWriter().write(arr + "");

		} catch (Exception e) {

			e.printStackTrace();

		}



	}



	protected void doPost(HttpServletRequest request, HttpServletResponse response)

			throws ServletException, IOException {

//		String pathname = request.getSession().getServletContext().getRealPath("/key.txt");

//		String password=request.getParameter("password");

//

//		try {

//			password=Decode(pathname,password);

//			response.getWriter().write(password);

//		} catch (Exception e) {

//			e.printStackTrace();

//		}

		String password=request.getParameter("password");



		String pathname = request.getSession().getServletContext().getRealPath("/key.txt");

		PublicKey publickey;

		try {

			publickey = getPubkeyfromFile(pathname);

			Cipher cipher = Cipher.getInstance("RSA");

			cipher.init(cipher.ENCRYPT_MODE, publickey); 

			byte[] result = cipher.doFinal("123".getBytes());

			System.out.println(Base64.getEncoder().encodeToString(result)); 

			System.out.println(password);

		} catch (Exception e) {

			// TODO Auto-generated catch block

			e.printStackTrace();

		}

	}

}