Web登录使用RSA对密码进行加密解密过程
RSA算法基于一个十分简单的数论事实：将两个大素数相乘十分容易，但那时想要对其乘积进行因式分解却极其困难，因此可以将乘积公开作为加密密钥。首先简单说一下RSA加密方式（借用知乎上面的理解，通俗易懂）：
A要发消息给B
B有一个盒子（公钥）一把锁（私钥）
A拿到盒子放消息进去，上锁。
快递给B，只有B能打开盒子。
即使中途被劫也无法打开盒子。
本文demo的实现逻辑如下：
1、在后台服务端构造一个产生特定的密钥对方法；
2、在jsp页面里通过调用后台服务端方法，产生密钥对，并将私钥以及公钥中获取到的publicExponent,Modulus保存session中；
3、在js中使用公钥中获取到的publicExponent,Modulus,重新生成一个key;
4、使用key来加密密码信息；
5、提交信息到后台，后台获取到加密信息，通过本地存储的私钥进行解密，安全地获得需要的信息。
下面直接贴代码了：
首先我创建的是一个maven项目，所以要添加一些依赖库，pom.xml配置如下
RSA工具类（主要构建rsa密钥对的工具类）：
package com.vernon.utils;
import java.math.BigInteger;
import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.NoSuchAlgorithmException;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.RSAPrivateKeySpec;
import java.security.spec.RSAPublicKeySpec;
import java.util.HashMap;
import javax.crypto.Cipher;
public class RSAUtils {
/**
* 生成公钥和私钥
* @throws NoSuchAlgorithmException
*
*/
public static HashMap getKeys() throws NoSuchAlgorithmException{
HashMap map = new HashMap();
KeyPairGenerator keyPairGen = KeyPairGenerator.getInstance("RSA", new org.bouncycastle.jce.provider.BouncyCastleProvider());
keyPairGen.initialize(1024);
KeyPair keyPair = keyPairGen.generateKeyPair();
RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();
RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate();
map.put("public", publicKey);
map.put("private", privateKey);
return map;
}
/**
* 使用模和指数生成RSA公钥
*
*
* @param modulus
* 模
* @param exponent
* 指数
* @return
*/
public static RSAPublicKey getPublicKey(String modulus, String exponent) {
try {
BigInteger b1 = new BigInteger(modulus);
BigInteger b2 = new BigInteger(exponent);
KeyFactory keyFactory = KeyFactory.getInstance("RSA", new org.bouncycastle.jce.provider.BouncyCastleProvider());
RSAPublicKeySpec keySpec = new RSAPublicKeySpec(b1, b2);
return (RSAPublicKey) keyFactory.generatePublic(keySpec);
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
/**
* 使用模和指数生成RSA私钥
* /None/NoPadding】
*
* @param modulus
* 模
* @param exponent
* 指数
* @return
*/
public static RSAPrivateKey getPrivateKey(String modulus, String exponent) {
try {
BigInteger b1 = new BigInteger(modulus);
BigInteger b2 = new BigInteger(exponent);
KeyFactory keyFactory = KeyFactory.getInstance("RSA", new org.bouncycastle.jce.provider.BouncyCastleProvider());
RSAPrivateKeySpec keySpec = new RSAPrivateKeySpec(b1, b2);
return (RSAPrivateKey) keyFactory.generatePrivate(keySpec);
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
/**
* 公钥加密
*
* @param data
* @param publicKey
* @return
* @throws Exception
*/
public static String encryptByPublicKey(String data, RSAPublicKey publicKey)
throws Exception {
Cipher cipher = Cipher.getInstance("RSA", new org.bouncycastle.jce.provider.BouncyCastleProvider());
cipher.init(Cipher.ENCRYPT_MODE, publicKey);
// 模长
int key_len = publicKey.getModulus().bitLength() / 8;
// 加密数据长度 <= 模长-11
String[] datas = splitString(data, key_len - 11);
String mi = "";
//如果明文长度大于模长-11则要分组加密
for (String s : datas) {
mi += bcd2Str(cipher.doFinal(s.getBytes()));
}
return mi;
}
/**
* 私钥解密
*
* @param data
* @param privateKey
* @return
* @throws Exception
*/
public static String decryptByPrivateKey(String data, RSAPrivateKey privateKey)
throws Exception {
Cipher cipher = Cipher.getInstance("RSA", new org.bouncycastle.jce.provider.BouncyCastleProvider());
cipher.init(Cipher.DECRYPT_MODE, privateKey);
//模长
int key_len = privateKey.getModulus().bitLength() / 8;
byte[] bytes = data.getBytes();
byte[] bcd = ASCII_To_BCD(bytes, bytes.length);
//System.err.println(bcd.length);
//如果密文长度大于模长则要分组解密
String ming = "";
byte[][] arrays = splitArray(bcd, key_len);
for(byte[] arr : arrays){
ming += new String(cipher.doFinal(arr));
}
return new StringBuilder(ming).reverse().toString();
}
/**
* ASCII码转BCD码
*
*/
public static byte[] ASCII_To_BCD(byte[] ascii, int asc_len) {
byte[] bcd = new byte[asc_len / 2];
int j = 0;
for (int i = 0; i < (asc_len + 1) / 2; i++) {
bcd[i] = asc_to_bcd(ascii[j++]);
bcd[i] = (byte) (((j >= asc_len) ? 0x00 : asc_to_bcd(ascii[j++])) + (bcd[i] << 4));
}
return bcd;
}
public static byte asc_to_bcd(byte asc) {
byte bcd;
if ((asc >= '0') && (asc <= '9'))
bcd = (byte) (asc - '0');
else if ((asc >= 'A') && (asc <= 'F'))
bcd = (byte) (asc - 'A' + 10);
else if ((asc >= 'a') && (asc <= 'f'))
bcd = (byte) (asc - 'a' + 10);
else
bcd = (byte) (asc - 48);
return bcd;
}
/**
* BCD转字符串
*/
public static String bcd2Str(byte[] bytes) {
char temp[] = new char[bytes.length * 2], val;
for (int i = 0; i < bytes.length; i++) {
val = (char) (((bytes[i] & 0xf0) >> 4) & 0x0f);
temp[i * 2] = (char) (val > 9 ? val + 'A' - 10 : val + '0');
val = (char) (bytes[i] & 0x0f);
temp[i * 2 + 1] = (char) (val > 9 ? val + 'A' - 10 : val + '0');
}
return new String(temp);
}
/**
* 拆分字符串
*/
public static String[] splitString(String string, int len) {
int x = string.length() / len;
int y = string.length() % len;
int z = 0;
if (y != 0) {
z = 1;
}
String[] strings = new String[x + z];
String str = "";
for (int i=0; i map = getKeys();
//生成公钥和私钥
RSAPublicKey publicKey = (RSAPublicKey) map.get("public");
RSAPrivateKey privateKey = (RSAPrivateKey) map.get("private");
//模
String modulus = publicKey.getModulus().toString();
System.out.println("pubkey modulus="+modulus);
//公钥指数
String public_exponent = publicKey.getPublicExponent().toString();
System.out.println("pubkey exponent="+public_exponent);
//私钥指数
String private_exponent = privateKey.getPrivateExponent().toString();
System.out.println("private exponent="+private_exponent);
//明文
String ming = "111";
//使用模和指数生成公钥和私钥
RSAPublicKey pubKey = RSAUtils.getPublicKey(modulus, public_exponent);
RSAPrivateKey priKey = RSAUtils.getPrivateKey(modulus, private_exponent);
//加密后的密文
String mi = RSAUtils.encryptByPublicKey(ming, pubKey);
System.err.println("mi="+mi);
//解密后的明文
String ming2 = RSAUtils.decryptByPrivateKey(mi, priKey);
System.err.println("ming2="+ming2);
}
} 然后是Java后台处理的Servlet代码，LoginAction：
package com.vernon.servlet;
import com.vernon.utils.RSAUtils;
import java.io.IOException;
import java.security.interfaces.RSAPrivateKey;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* MyEclipse Struts Creation date: 06-28-2008
*
* XDoclet definition:
*
* @struts.action path="/login" name="loginForm" input="/login.jsp"
* scope="request" validate="true"
* @struts.action-forward name="error" path="/error.jsp"
* @struts.action-forward name="success" path="/success.jsp"
*/
public class LoginAction extends HttpServlet {
/*
* Generated Methods
*/
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) {
try {
execute(req,resp);
} catch (Exception e) {
e.printStackTrace();
}
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
doGet(req,resp);
}
/**
* Method execute
*
* @param request
* @param response
* @return ActionForward
*/
public boolean execute(HttpServletRequest request,
HttpServletResponse response) throws Exception {
String password = request.getParameter("password");
RSAPrivateKey privateKey = (RSAPrivateKey)request.getSession().getAttribute("privateKey");
String descrypedPwd = RSAUtils.decryptByPrivateKey(password, privateKey); //解密后的密码,password是提交过来的密码
System.out.println("======解码前："+password+"===========");
System.out.println("======解码后："+descrypedPwd+"===========");
return true;
}
} 登录页（没做样式了，本文关键是如何实现rsa加密解密过程）：
<%@ page import="com.vernon.utils.RSAUtils" %>
<%@ page import="java.security.interfaces.RSAPublicKey" %>
<%@ page import="java.security.interfaces.RSAPrivateKey" %>
<%@ page import="java.util.HashMap" %>
<%@ page language="java" pageEncoding="UTF-8" contentType="text/html; charset=UTF-8"%>
login
贴出js代码吧，网上找的
result.digits[j] = RSAUtils.hexToDigit(s.substr(Math.max(i - 4, 0), Math.min(i, 4)));
}
return result;
};
RSAUtils.biFromString = function(s, radix) {
var isNeg = s.charAt(0) == '-';
var istop = isNeg ? 1 : 0;
var result = new BigInt();
var place = new BigInt();
place.digits[0] = 1; // radix^0
for (var i = s.length - 1; i >= istop; i--) {
var c = s.charCodeAt(i);
var digit = RSAUtils.charToHex(c);
var biDigit = RSAUtils.biMultiplyDigit(place, digit);
result = RSAUtils.biAdd(result, biDigit);
place = RSAUtils.biMultiplyDigit(place, radix);
}
result.isNeg = isNeg;
return result;
};
RSAUtils.biDump = function(b) {
return (b.isNeg ? "-" : "") + b.digits.join(" ");
};
RSAUtils.biAdd = function(x, y) {
var result;
if (x.isNeg != y.isNeg) {
y.isNeg = !y.isNeg;
result = RSAUtils.biSubtract(x, y);
y.isNeg = !y.isNeg;
}
else {
result = new BigInt();
var c = 0;
var n;
for (var i = 0; i < x.digits.length; ++i) {
n = x.digits[i] + y.digits[i] + c;
result.digits[i] = n % biRadix;
c = Number(n >= biRadix);
}
result.isNeg = x.isNeg;
}
return result;
};
RSAUtils.biSubtract = function(x, y) {
var result;
if (x.isNeg != y.isNeg) {
y.isNeg = !y.isNeg;
result = RSAUtils.biAdd(x, y);
y.isNeg = !y.isNeg;
} else {
result = new BigInt();
var n, c;
c = 0;
for (var i = 0; i < x.digits.length; ++i) {
n = x.digits[i] - y.digits[i] + c;
result.digits[i] = n % biRadix;
// Stupid non-conforming modulus operation.
if (result.digits[i] < 0) result.digits[i] += biRadix;
c = 0 - Number(n < 0);
}
// Fix up the negative sign, if any.
if (c == -1) {
c = 0;
for (var i = 0; i < x.digits.length; ++i) {
n = 0 - result.digits[i] + c;
result.digits[i] = n % biRadix;
// Stupid non-conforming modulus operation.
if (result.digits[i] < 0) result.digits[i] += biRadix;
c = 0 - Number(n < 0);
}
// Result is opposite sign of arguments.
result.isNeg = !x.isNeg;
} else {
// Result is same sign.
result.isNeg = x.isNeg;
}
}
return result;
};
RSAUtils.biHighIndex = function(x) {
var result = x.digits.length - 1;
while (result > 0 && x.digits[result] == 0) --result;
return result;
};
RSAUtils.biNumBits = function(x) {
var n = RSAUtils.biHighIndex(x);
var d = x.digits[n];
var m = (n + 1) * bitsPerDigit;
var result;
for (result = m; result > m - bitsPerDigit; --result) {
if ((d & 0x8000) != 0) break;
d <<= 1;
}
return result;
};
RSAUtils.biMultiply = function(x, y) {
var result = new BigInt();
var c;
var n = RSAUtils.biHighIndex(x);
var t = RSAUtils.biHighIndex(y);
var u, uv, k;
for (var i = 0; i <= t; ++i) {
c = 0;
k = i;
for (j = 0; j <= n; ++j, ++k) {
uv = result.digits[k] + x.digits[j] * y.digits[i] + c;
result.digits[k] = uv & maxDigitVal;
c = uv >>> biRadixBits;
//c = Math.floor(uv / biRadix);
}
result.digits[i + n + 1] = c;
}
// Someone give me a logical xor, please.
result.isNeg = x.isNeg != y.isNeg;
return result;
};
RSAUtils.biMultiplyDigit = function(x, y) {
var n, c, uv;
result = new BigInt();
n = RSAUtils.biHighIndex(x);
c = 0;
for (var j = 0; j <= n; ++j) {
uv = result.digits[j] + x.digits[j] * y + c;
result.digits[j] = uv & maxDigitVal;
c = uv >>> biRadixBits;
//c = Math.floor(uv / biRadix);
}
result.digits[1 + n] = c;
return result;
};
RSAUtils.arrayCopy = function(src, srcStart, dest, destStart, n) {
var m = Math.min(srcStart + n, src.length);
for (var i = srcStart, j = destStart; i < m; ++i, ++j) {
dest[j] = src[i];
}
};
var highBitMasks = [0x0000, 0x8000, 0xC000, 0xE000, 0xF000, 0xF800,
0xFC00, 0xFE00, 0xFF00, 0xFF80, 0xFFC0, 0xFFE0,
0xFFF0, 0xFFF8, 0xFFFC, 0xFFFE, 0xFFFF];
RSAUtils.biShiftLeft = function(x, n) {
var digitCount = Math.floor(n / bitsPerDigit);
var result = new BigInt();
RSAUtils.arrayCopy(x.digits, 0, result.digits, digitCount,
result.digits.length - digitCount);
var bits = n % bitsPerDigit;
var rightBits = bitsPerDigit - bits;
for (var i = result.digits.length - 1, i1 = i - 1; i > 0; --i, --i1) {
result.digits[i] = ((result.digits[i] << bits) & maxDigitVal) |
((result.digits[i1] & highBitMasks[bits]) >>>
(rightBits));
}
result.digits[0] = ((result.digits[i] << bits) & maxDigitVal);
result.isNeg = x.isNeg;
return result;
};
var lowBitMasks = [0x0000, 0x0001, 0x0003, 0x0007, 0x000F, 0x001F,
0x003F, 0x007F, 0x00FF, 0x01FF, 0x03FF, 0x07FF,
0x0FFF, 0x1FFF, 0x3FFF, 0x7FFF, 0xFFFF];
RSAUtils.biShiftRight = function(x, n) {
var digitCount = Math.floor(n / bitsPerDigit);
var result = new BigInt();
RSAUtils.arrayCopy(x.digits, digitCount, result.digits, 0,
x.digits.length - digitCount);
var bits = n % bitsPerDigit;
var leftBits = bitsPerDigit - bits;
for (var i = 0, i1 = i + 1; i < result.digits.length - 1; ++i, ++i1) {
result.digits[i] = (result.digits[i] >>> bits) |
((result.digits[i1] & lowBitMasks[bits]) << leftBits);
}
result.digits[result.digits.length - 1] >>>= bits;
result.isNeg = x.isNeg;
return result;
};
RSAUtils.biMultiplyByRadixPower = function(x, n) {
var result = new BigInt();
RSAUtils.arrayCopy(x.digits, 0, result.digits, n, result.digits.length - n);
return result;
};
RSAUtils.biDivideByRadixPower = function(x, n) {
var result = new BigInt();
RSAUtils.arrayCopy(x.digits, n, result.digits, 0, result.digits.length - n);
return result;
};
RSAUtils.biModuloByRadixPower = function(x, n) {
var result = new BigInt();
RSAUtils.arrayCopy(x.digits, 0, result.digits, 0, n);
return result;
};
RSAUtils.biCompare = function(x, y) {
if (x.isNeg != y.isNeg) {
return 1 - 2 * Number(x.isNeg);
}
for (var i = x.digits.length - 1; i >= 0; --i) {
if (x.digits[i] != y.digits[i]) {
if (x.isNeg) {
return 1 - 2 * Number(x.digits[i] > y.digits[i]);
} else {
return 1 - 2 * Number(x.digits[i] < y.digits[i]);
}
}
}
return 0;
};
RSAUtils.biDivideModulo = function(x, y) {
var nb = RSAUtils.biNumBits(x);
var tb = RSAUtils.biNumBits(y);
var origYIsNeg = y.isNeg;
var q, r;
if (nb < tb) {
// |x| < |y|
if (x.isNeg) {
q = RSAUtils.biCopy(bigOne);
q.isNeg = !y.isNeg;
x.isNeg = false;
y.isNeg = false;
r = biSubtract(y, x);
// Restore signs, 'cause they're references.
x.isNeg = true;
y.isNeg = origYIsNeg;
} else {
q = new BigInt();
r = RSAUtils.biCopy(x);
}
return [q, r];
}
q = new BigInt();
r = x;
// Normalize Y.
var t = Math.ceil(tb / bitsPerDigit) - 1;
var lambda = 0;
while (y.digits[t] < biHalfRadix) {
y = RSAUtils.biShiftLeft(y, 1);
++lambda;
++tb;
t = Math.ceil(tb / bitsPerDigit) - 1;
}
// Shift r over to keep the quotient constant. We'll shift the
// remainder back at the end.
r = RSAUtils.biShiftLeft(r, lambda);
nb += lambda; // Update the bit count for x.
var n = Math.ceil(nb / bitsPerDigit) - 1;
var b = RSAUtils.biMultiplyByRadixPower(y, n - t);
while (RSAUtils.biCompare(r, b) != -1) {
++q.digits[n - t];
r = RSAUtils.biSubtract(r, b);
}
for (var i = n; i > t; --i) {
var ri = (i >= r.digits.length) ? 0 : r.digits[i];
var ri1 = (i - 1 >= r.digits.length) ? 0 : r.digits[i - 1];
var ri2 = (i - 2 >= r.digits.length) ? 0 : r.digits[i - 2];
var yt = (t >= y.digits.length) ? 0 : y.digits[t];
var yt1 = (t - 1 >= y.digits.length) ? 0 : y.digits[t - 1];
if (ri == yt) {
q.digits[i - t - 1] = maxDigitVal;
} else {
q.digits[i - t - 1] = Math.floor((ri * biRadix + ri1) / yt);
}
var c1 = q.digits[i - t - 1] * ((yt * biRadix) + yt1);
var c2 = (ri * biRadixSquared) + ((ri1 * biRadix) + ri2);
while (c1 > c2) {
--q.digits[i - t - 1];
c1 = q.digits[i - t - 1] * ((yt * biRadix) | yt1);
c2 = (ri * biRadix * biRadix) + ((ri1 * biRadix) + ri2);
}
b = RSAUtils.biMultiplyByRadixPower(y, i - t - 1);
r = RSAUtils.biSubtract(r, RSAUtils.biMultiplyDigit(b, q.digits[i - t - 1]));
if (r.isNeg) {
r = RSAUtils.biAdd(r, b);
--q.digits[i - t - 1];
}
}
r = RSAUtils.biShiftRight(r, lambda);
// Fiddle with the signs and stuff to make sure that 0 <= r < y.
q.isNeg = x.isNeg != origYIsNeg;
if (x.isNeg) {
if (origYIsNeg) {
q = RSAUtils.biAdd(q, bigOne);
} else {
q = RSAUtils.biSubtract(q, bigOne);
}
y = RSAUtils.biShiftRight(y, lambda);
r = RSAUtils.biSubtract(y, r);
}
// Check for the unbelievably stupid degenerate case of r == -0.
if (r.digits[0] == 0 && RSAUtils.biHighIndex(r) == 0) r.isNeg = false;
return [q, r];
};
RSAUtils.biDivide = function(x, y) {
return RSAUtils.biDivideModulo(x, y)[0];
};
RSAUtils.biModulo = function(x, y) {
return RSAUtils.biDivideModulo(x, y)[1];
};
RSAUtils.biMultiplyMod = function(x, y, m) {
return RSAUtils.biModulo(RSAUtils.biMultiply(x, y), m);
};
RSAUtils.biPow = function(x, y) {
var result = bigOne;
var a = x;
while (true) {
if ((y & 1) != 0) result = RSAUtils.biMultiply(result, a);
y >>= 1;
if (y == 0) break;
a = RSAUtils.biMultiply(a, a);
}
return result;
};
RSAUtils.biPowMod = function(x, y, m) {
var result = bigOne;
var a = x;
var k = y;
while (true) {
if ((k.digits[0] & 1) != 0) result = RSAUtils.biMultiplyMod(result, a, m);
k = RSAUtils.biShiftRight(k, 1);
if (k.digits[0] == 0 && RSAUtils.biHighIndex(k) == 0) break;
a = RSAUtils.biMultiplyMod(a, a, m);
}
return result;
};
$w.BarrettMu = function(m) {
this.modulus = RSAUtils.biCopy(m);
this.k = RSAUtils.biHighIndex(this.modulus) + 1;
var b2k = new BigInt();
b2k.digits[2 * this.k] = 1; // b2k = b^(2k)
this.mu = RSAUtils.biDivide(b2k, this.modulus);
this.bkplus1 = new BigInt();
this.bkplus1.digits[this.k + 1] = 1; // bkplus1 = b^(k+1)
this.modulo = BarrettMu_modulo;
this.multiplyMod = BarrettMu_multiplyMod;
this.powMod = BarrettMu_powMod;
};
function BarrettMu_modulo(x) {
var $dmath = RSAUtils;
var q1 = $dmath.biDivideByRadixPower(x, this.k - 1);
var q2 = $dmath.biMultiply(q1, this.mu);
var q3 = $dmath.biDivideByRadixPower(q2, this.k + 1);
var r1 = $dmath.biModuloByRadixPower(x, this.k + 1);
var r2term = $dmath.biMultiply(q3, this.modulus);
var r2 = $dmath.biModuloByRadixPower(r2term, this.k + 1);
var r = $dmath.biSubtract(r1, r2);
if (r.isNeg) {
r = $dmath.biAdd(r, this.bkplus1);
}
var rgtem = $dmath.biCompare(r, this.modulus) >= 0;
while (rgtem) {
r = $dmath.biSubtract(r, this.modulus);
rgtem = $dmath.biCompare(r, this.modulus) >= 0;
}
return r;
}
function BarrettMu_multiplyMod(x, y) {
/*
x = this.modulo(x);
y = this.modulo(y);
*/
var xy = RSAUtils.biMultiply(x, y);
return this.modulo(xy);
}
function BarrettMu_powMod(x, y) {
var result = new BigInt();
result.digits[0] = 1;
var a = x;
var k = y;
while (true) {
if ((k.digits[0] & 1) != 0) result = this.multiplyMod(result, a);
k = RSAUtils.biShiftRight(k, 1);
if (k.digits[0] == 0 && RSAUtils.biHighIndex(k) == 0) break;
a = this.multiplyMod(a, a);
}
return result;
}
var RSAKeyPair = function(encryptionExponent, decryptionExponent, modulus) {
var $dmath = RSAUtils;
this.e = $dmath.biFromHex(encryptionExponent);
this.d = $dmath.biFromHex(decryptionExponent);
this.m = $dmath.biFromHex(modulus);
// We can do two bytes per digit, so
// chunkSize = 2 * (number of digits in modulus - 1).
// Since biHighIndex returns the high index, not the number of digits, 1 has
// already been subtracted.
this.chunkSize = 2 * $dmath.biHighIndex(this.m);
this.radix = 16;
this.barrett = new $w.BarrettMu(this.m);
};
RSAUtils.getKeyPair = function(encryptionExponent, decryptionExponent, modulus) {
return new RSAKeyPair(encryptionExponent, decryptionExponent, modulus);
};
if(typeof $w.twoDigit === 'undefined') {
$w.twoDigit = function(n) {
return (n < 10 ? "0" : "") + String(n);
};
}
// Altered by Rob Saunders ([email protected]). New routine pads the
// string after it has been converted to an array. This fixes an
// incompatibility with Flash MX's ActionScript.
RSAUtils.encryptedString = function(key, s) {
var a = [];
var sl = s.length;
var i = 0;
while (i < sl) {
a[i] = s.charCodeAt(i);
i++;
}
while (a.length % key.chunkSize != 0) {
a[i++] = 0;
}
var al = a.length;
var result = "";
var j, k, block;
for (i = 0; i < al; i += key.chunkSize) {
block = new BigInt();
j = 0;
for (k = i; k < i + key.chunkSize; ++j) {
block.digits[j] = a[k++];
block.digits[j] += a[k++] << 8;
}
var crypt = key.barrett.powMod(block, key.e);
var text = key.radix == 16 ? RSAUtils.biToHex(crypt) : RSAUtils.biToString(crypt, key.radix);
result += text + " ";
}
return result.substring(0, result.length - 1); // Remove last space.
};
RSAUtils.decryptedString = function(key, s) {
var blocks = s.split(" ");
var result = "";
var i, j, block;
for (i = 0; i < blocks.length; ++i) {
var bi;
if (key.radix == 16) {
bi = RSAUtils.biFromHex(blocks[i]);
}
else {
bi = RSAUtils.biFromString(blocks[i], key.radix);
}
block = key.barrett.powMod(bi, key.d);
for (j = 0; j <= RSAUtils.biHighIndex(block); ++j) {
result += String.fromCharCode(block.digits[j] & 255,
block.digits[j] >> 8);
}
}
// Remove trailing null, if any.
if (result.charCodeAt(result.length - 1) == 0) {
result = result.substring(0, result.length - 1);
}
return result;
};
RSAUtils.setMaxDigits(130);
})(window); 以上。运行后是下面这样：
点击提交后后台打印信息：
如此便完成了RSA加密和解密过程。
补充：
这里还有一点要注意：直接运行的话，页面会报错：
java.lang.NoClassDefFoundError: org.bouncycastle.jce.provider.Bounc.CastleProvider
解决办法：
原因是因为加入了jdk的第三方安全库，需要额外配置
1.查看JAVA_HOME配置路径
2.将bcprov-jdk15on-1.59.jar放入JAVA_HOME/jre/lib/ext下
(注：不知道文件放哪的，可以直接找到这个项目，查看当前的架包名，找到本地仓库地址，就可以找到了，当然你全局搜索也是可以的。。。)
3.打开JAVA_HOME/jre/lib/security下的java.security文件，在下面加上
security.provider.x=org.bouncycastle.jce.provider.BouncyCastleProvider
如此，便能完美运行了。
本文参考博客：https://blog.csdn.net/yys79/article/details/41514871/
http://www.cnblogs.com/yangy608/archive/2012/08/08/2627858.html）
这里做下简单记录。