node.js 使用crypto模块进行RSA加解密操作

多余的话不说了，直接上代码

先在package.json配置文件里添加crypto模块的支持。

"dependencies": {
......

"crypto":"~1.0.1",

}

 加密工具类： 
 注：公钥，私钥怎么生成这里不介绍了，网上很多。

生成后保存成pem文件，放到工程目录下引用即可

//加密解密类

var crypto = require('crypto');
var fs = require('fs');
var path = require('path');

/**
* RSA最大加密明文大小
*/
var MAX_ENCRYPT_BLOCK = 117-31;

/**
* RSA最大解密密文大小
*/
var MAX_DECRYPT_BLOCK = 128;

/**
* 公钥加密
* @param data
* @returns {string}
*/
function publicEncrypt(data) {
//得到公钥
var publicPem = fs.readFileSync(path.join(__dirname, "../../properties/rsa_public_key.pem"));//替换你自己的路径
var publicKey = publicPem.toString();
//加密信息用buf封装
var buf = new Buffer(data, "utf-8");
//buf转byte数组
var inputLen = buf.byteLength;
//密文
var bufs = [];
//开始长度
var offSet = 0;
//结束长度
var endOffSet = MAX_ENCRYPT_BLOCK;
//分段加密
while (inputLen - offSet > 0) {
if (inputLen - offSet > MAX_ENCRYPT_BLOCK) {
var bufTmp = buf.slice(offSet, endOffSet);
bufs.push(crypto.publicEncrypt({key: publicKey, padding: crypto.RSA_PKCS1_PADDING}, bufTmp));
} else {
var bufTmp = buf.slice(offSet, inputLen);
bufs.push(crypto.publicEncrypt({key: publicKey, padding: crypto.RSA_PKCS1_PADDING}, bufTmp));
}
offSet += MAX_ENCRYPT_BLOCK;
endOffSet += MAX_ENCRYPT_BLOCK;
}
var result = Buffer.concat(bufs);
//密文BASE64编码
var base64Str = result.toString("base64");
console.log(base64Str);
return base64Str;
}

/**
* 公钥解密
* @param date
* @returns {string}
*/
function publicDecrypt(date) {

//得到私钥
var publicPem = fs.readFileSync(path.join(__dirname, "../../properties/rsa_public_key.pem"));//替换你自己的路径
var publicKey = publicPem.toString();
//经过base64编码的密文转成buf
var buf = new Buffer(date, "base64");

//buf转byte数组
//var inputLen = bytes(buf, "base64");
var inputLen = buf.byteLength;
//密文
var bufs = [];
//开始长度
var offSet = 0;
//结束长度
var endOffSet = MAX_DECRYPT_BLOCK;
//分段加密
while (inputLen - offSet > 0) {
if (inputLen - offSet > MAX_DECRYPT_BLOCK) {
var bufTmp = buf.slice(offSet, endOffSet);
bufs.push(crypto.publicDecrypt({key: publicKey, padding: crypto.RSA_PKCS1_PADDING}, bufTmp));
} else {
var bufTmp = buf.slice(offSet, inputLen);
bufs.push(crypto.publicDecrypt({key: publicKey, padding: crypto.RSA_PKCS1_PADDING}, bufTmp));
}
offSet += MAX_DECRYPT_BLOCK;
endOffSet += MAX_DECRYPT_BLOCK;
}
var result = Buffer.concat(bufs).toString();
console.log(result);
return result;
}

/**
* 私钥加密
* @param date
* @returns {string}
*/
function privateEncrypt(date) {

//得到私钥
var privatePem = fs.readFileSync(path.join(__dirname, "../../properties/rsa_private_key.pem"));
var privateKey = privatePem.toString();
//经过base64编码的密文转成buf
var buf = new Buffer(date, "utf-8");
//buf转byte数组
var inputLen = buf.byteLength;
//密文
var bufs = [];
//开始长度
var offSet = 0;
//结束长度
var endOffSet = MAX_ENCRYPT_BLOCK;
//分段加密
while (inputLen - offSet > 0) {
if (inputLen - offSet > MAX_ENCRYPT_BLOCK) {
var bufTmp = buf.slice(offSet, endOffSet);
bufs.push(crypto.privateEncrypt({key: privateKey, padding: crypto.RSA_PKCS1_PADDING}, bufTmp));
} else {
var bufTmp = buf.slice(offSet, inputLen);
bufs.push(crypto.privateEncrypt({key: privateKey, padding: crypto.RSA_PKCS1_PADDING}, bufTmp));
}
offSet += MAX_ENCRYPT_BLOCK;
endOffSet += MAX_ENCRYPT_BLOCK;
}
var result = Buffer.concat(bufs);
//密文BASE64编码
var base64Str = result.toString("base64");
console.log(base64Str);
return base64Str;
}

/**
* 私钥解密
* @param date
* @returns {string}
*/
function privateDecrypt(date) {

//得到私钥
var privatePem = fs.readFileSync(path.join(__dirname, "../../properties/rsa_private_key.pem"));
var privateKey = privatePem.toString();
//经过base64编码的密文转成buf
var buf = new Buffer(date, "base64");

//buf转byte数组
//var inputLen = bytes(buf, "base64");
var inputLen = buf.byteLength;
//密文
var bufs = [];
//开始长度
var offSet = 0;
//结束长度
var endOffSet = MAX_DECRYPT_BLOCK;
//分段加密
while (inputLen - offSet > 0) {
if (inputLen - offSet >
b7d1
MAX_DECRYPT_BLOCK) {
var bufTmp = buf.slice(offSet, endOffSet);
bufs.push(crypto.privateDecrypt({key: privateKey, padding: crypto.RSA_PKCS1_PADDING}, bufTmp));
} else {
var bufTmp = buf.slice(offSet, inputLen);
bufs.push(crypto.privateDecrypt({key: privateKey, padding: crypto.RSA_PKCS1_PADDING}, bufTmp));
}
offSet += MAX_DECRYPT_BLOCK;
endOffSet += MAX_DECRYPT_BLOCK;
}
var result = Buffer.concat(bufs).toString();
console.log(result);
//解密
return result;
}

module.exports.publicEncrypt = publicEncrypt;
module.exports.publicDecrypt = publicDecrypt;
module.exports.privateEncrypt = privateEncrypt;
module.exports.privateDecrypt = privateDecrypt;

使用：

var str = cryptoUtil.publicEncrypt("123456789");//公钥加密
var deStr = cryptoUtil.privateDecrypt(str);//私钥解密

完。