How does Node implement encryption and decryption of data transmission? The following article will introduce to you how Node.js implements encryption and decryption of front-end and back-end data transmission. I hope it will be helpful to you! 
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During the front-end and back-end communication process, some sensitive information, especially the user's account and password, need to be encrypted for transmission. How to choose the encryption method is also a science, but there is no need to go too far here. Generally speaking, the most commonly used transmission data encryption in B/S architecture is RSA encryption. The core idea is public key encryption and private key decryption . The public key can be understood as a key that can be made public. The server sends the public key to the client. The client uses the public key to encrypt and transmit the data. The server receives the ciphertext from the client and then uses its own paired private key. Decrypt it to get the original data.
The general process is shown in the figure below:
There is a core module in Nodejs - crypto which provides various encryption and decryption related APIs. The following examples are written based on [email protected] version.
const crypto = require('crypto');
/**
* Generate RSA public and private key pairs * @return {*} publicKey: public key; privateKey: private key */
function genRSAKeyPaire() {
const { publicKey, privateKey } = crypto.generateKeyPairSync('rsa', {
modulusLength: 4096,
publicKeyEncoding: {
type: 'pkcs1',
format: 'pem',
},
privateKeyEncoding: {
type: 'pkcs1',
format: 'pem',
},
});
return { publicKey, privateKey };
}
//Print the generated public and private key pairs console.log(genRSAKeyPaire());Example output is as follows:
(Part of the sample public and private keys has been deleted, please do not use it for experiments)
{
publicKey: '-----BEGIN RSA PUBLIC KEY-----n' +
'MIICCgKCAgEAsitohTu9Jf2h+NPV4tNfFhPrlbStzXNM8wSEcskwtpwi6aZfgQC7n' +
'/A7M1hN8Zk8WgiZjy05AHinWPvXo70OWj8TminIAjB2wh0nDqm+IQqN7r20uzeJmn' +
'GBf1KusGemChEiFwiad1h/OB9z9LC8zMYR/G+XAbFfcv8MxAMI9mgmS8t5+xeYm6n' +
'EMiCQkQjfqpErhW3oESj8hrdJdOZbiK3l0TgYLyjZRQu6pHzFkmd9We3BY1qcXo1n' +
'2BtNKvqoH9QDJItsb3S9v2mOGl1rbItKlDrqYCdGY4iyXVIfagNWHraVzHqH/tern' +
'X+hOmLOwu+Npkz+oEDmnUq1UGY181PBGiNwHVodXx+DF5ckj/bGIxFG2nSiNe3dOn' +
'WLxV3+W8Af0006Oe+fRo1D7xt5SK5AipCpylKKYdyuP3MJ5dpPu7GMIcwj20Ndnun' +
'cDJJ2HH9kZAKz6/r62S7ALluFSecuZr0Dqc6SrJs43zBTpS/hSI33r01ste6Zel8n' +
'uRZKW/4FhUg8gW1KCM+Mp1MaZufOurCDc1Iec0SI71Tteg52BTpfb8cQ9Z1h0xWRn' +
'FdbmLMLuJkIi5oG2+FLAqlGknik0AxXpnlivSOW5Q+eLOh0DjQxxU2sCAwEAAQ==n' +
'-----END RSA PUBLIC KEY-----n',
privateKey: '-----BEGIN RSA PRIVATE KEY-----n' +
'MIIJKQIBAAKCAgEAsitohTu9Jf2h+NPV4tNfFhPrlbStzXNM8wSEcskwtpwi6aZfn' +
'gQC7/A7M1hN8Zk8WgiZjy05AHinWPvXo70OWj8TminIAjB2wh0nDqm+IQqN7r20un' +
'zeJmGBf1KusGemChEiFwiad1h/OB9z9LC8zMYR/G+XAbFfcv8MxAMI9mgmS8t5+xn' +
'eYm6EMiCQkQjfqpErhW3oESj8hrdJdOZbiK3l0TgYLyjZRQu6pHzFkmd9We3BY1qn' +
'cXo12BtNKvqoH9QDJItsb3S9v2mOGl1rbItKlDrqYCdGY4iyXVIfagNWHraVzHqHn' +
'/terX+hOmLOwu+Npkz+oEDmnUq1UGY181PBGiNwHVodXx+DF5ckj/bGIxFG2nSiNn' +
'e3dOWLxV3+W8Af0006Oe+fRo1D7xt5SK5AipCpylKKYdyuP3MJ5dpPu7GMIcwj20n' +
'NdnucDJJ2HH9kZAKz6/r62S7ALluFSecuZr0Dqc6SrJs43zBTpS/hSI33r01ste6n' +
'Zel8uRZKW/4FhUg8gW1KCM+Mp1MaZufOurCDc1Iec0SI71Tteg52BTpfb8cQ9Z1hn' +
'0xWRd+u6S+oP8/hl5bdtSZhT1ZTK8Q/BF99+qOT0q4KGGu9aM8kOuMk2BI3qIN7kn' +
'0zAQFdbmLMLuJkIi5oG2+FLAqlGknik0AxXpnlivSOW5Q+eLOh0DjQxxU2sCAwEAn' +
'AQKCAgA9hxAJMqAXRodwznbGZggoL6jjggmjMXYZVi4HFcNkzHaiCXphqkdAvDuwn' +
'kfobuqQjPe6oftVVlU0PYQyX09divrR+iu/1cytLDQYtDWcY3CwSYLoRD2YCXAOmn' +
'VpNeH5CAGlwqrVHBKS5wm8LmyEqsH7Uu3q/73ekIVwCzxFG6Jd+l6df4CL/gm92fn' +
'1LgNPe+JzqYjCpEzQmOsdG4/wm10J6z0uzAR7+5jwxMXV0TdQnvJxxRDK9j8UDFNn' +
'7lGw7B5JuHwx4TbFq0YPhMNcMJ4Iom/d1LJSHRq7b2i5y30qDhOdEZN1RjVAYZECn' +
'2srll5sV5p27PK2zt3ebe2jogDFa7crOyKV7zkNZRNfrC1wVAcxq5+WaAinXtJRbn' +
'/CbtW5uboXC/kwRU0l5BAXg6MNoeMZCg4wMp8cXnVYxrodon31QVcC1HsV5Rx3Dmn' +
'R9+giZcWoxDm314oy3mxmbMKQ/it6Pf2kMGLbmEYXFFdTSr/ZWY5+ZaaO6GgM59on' +
'anh0FHt0xBEyE11Pivck6jMyl7eCp+yeOPhJxsaFLLH8SJnjWluAkrGwqzXeRB/in' +
'u5mGr+2zK4844kQDg7zUAdaFFYEixGwpu21XOEv+5ODSwecpVFSrwIp3LXFkfAirn' +
'vBGUeSWdFI98Ehdi8eOC+11hif9AxtNMmNqnl/eK0D44WAkZAQKCAQEA6WBZ9agbn' +
'VMhckT09WlGQfyiWHh9pnpEr+NPu2fRgkAh5AcrWG8PeD3QAIXFz1CMgKsGxa6Mzn' +
'SkM04ZMYGYC5Zv3KPWxwcPCVskycozo0eDkFrT7pC7N2ZZNFcDRmTAiX1CkAx1RYn' +
'iihws2Vl5gahGlUSwjgpssfjFL68iPGz1i2F7yossP+8tZO88SUPuDbahhX/QEkVn' +
'1P5uL43Rf4aGjcBWv5x3BAPpYOsn//AUPEeT0jNe2IQ81c92SYa8M0fBdXkXmhfNn' +
'FUXLvMUD3XSEMgFXvS1zIoP8F1sG8HZA0p5LNugYZuyIeUPOUCkoHKl/TzMQyl07n' +
'7Yi7a2ONYrSOEQKCAQEAw3EAgvp1wdegHEnACDoA5ls1afuqx5ewt8nJCwXfHOWCn' +
'B33MwEIOc6/Phf+EMQkjl/+r2mv3jk2I3WqGkaAQs8H68GnjSZ0VKebRSmXhpiqmn' +
'Jsl99LVIKO8GJ2Igjccn5buZRWes4fxr4/TvM2lLNJhrmeQahpEMbCYLwRSO+BTZn' +
'p4CGja5GXtSUDKagnvXhGyFzI5OF5XYyHLjdMN5i4v/HVhlMLVmwReAqY/fZ1iFcn' +
'jyRUbSMOBo6fE5HI8NO481c4m1e96Cj1BgwWE+mNcNXfPj3CDlrxJY848+PYpT8Jn' +
'8EPfc2+hPhufFfBgXWpZbPrHIG97UsqhWr3aq/u9uwKCAQEArPJJWGJe9sKQztU6n' +
'PU+KrKEwNlyDEg51Lq4oKH8QfEy7GBfv+Z16V6tYWXBRLRlmwijOSX0lClipvK0cn' +
'Q/H/85IKKODOpvOzi/F4dwIwVhOz4EJpw9EX4Yh1AgTi9l+73G8Sc6VPA/uaIWf4n' +
'TrIE+5WmFCY4yJOW9g2vfDDaW9NamPWBLx4mA83bTD1x28tSv+FXSpWexzxR/Y20n' +
'fjP8TNoHr3HNRT182uUJvIJ3DIDiy/hjxkKhLrXS7AQcPkhj1qGJWxleUvBpXpgGn' +
'GDw7py8VjU08MIzs6YX8q4CG406JYMQ5KTUKogscvozxe+QkQ1YNkFntikc01Q1un' +
'foJdcQKCAQAfJUb7mIZjmcU+PNKJfRTfoPFmLmEM5bOX1mRfiVQA+uI552ZVzTEYn' +
'ZpAfvpSGa/psIqZ0bHhLCTgicPN5CZUf0G35GibKeGoC/3Gi9ZF8NZe83qdf8/PHn' +
'8i983zpo3bASAE9wrBD1ApD/Bu2Ht+PwQcoEAEHp5/ue0IFXB7uw9UGqW+UVdwxnn' +
'2GCvk25NZsm01SPQK5ZO9wMNaLh3LTl9C13s7qMhJwXcXNjkjX79jNt/RD7gFZIKn' +
'oXfgWn83QcZboS64Msdk1AIYMJzkF3ge3zZwaM8gEoYTgjuFQm4oB1/CFk7pyoRbn' +
'rXMwv9nbiTMvFtfc52czzm7gUxkiB0A5AoIBAQCffC5rDhDGPiwJOft0PYNK/Ctkn' +
'3QZa2+t1ni0HYQhPok5OSgAOZwkZItGDGXdrvXe4+q/ttLLu6KhVaVRVoe+VzMpln' +
'WKp0RMBt999JS2XAipbguTQXrfsev0RNam0AFREUZdPNvrwLprQAwTl0iC2t4H6bn' +
'RybgQU6RpORFDvpwmkBjJ9Q2p540LmN0NVHq6Axv+g4TI2XdXlw8T7VQbJGKvfuJn' +
'g7j4+f7J+KpN5rHudiEPIVOK8V7Ap8dxP+lwEhZjK1MvCJE+SXWTkrRcY/TXn' +
'-----END RSA PRIVATE KEY-----n'
}2. Public key encryption
Based on the public and private key pair, the public key is used for encryption. The sample code is as follows:
const crypto = require('crypto');
/**
* Generate a public and private key pair * @return {*} publicKey: public key; privateKey: private key */
function genRSAKeyPaire() {
const { publicKey, privateKey } = crypto.generateKeyPairSync('rsa', {
modulusLength: 4096,
publicKeyEncoding: {
type: 'pkcs1',
format: 'pem',
},
privateKeyEncoding: {
type: 'pkcs1',
format: 'pem',
},
});
return { publicKey, privateKey };
}
const { publicKey } = genRSAKeyPaire();
/**
* Use public key for encryption * @param {String} data
* @param {String} publicKey
* @return {String} encrypted ciphertext */
function publicKeyEncrypt(data, publicKey) {
return crypto.publicEncrypt(publicKey, Buffer.from(data)).toString('base64')
}
const entry = {
name: 'zhangsan',
password: '123456'
};
// Convert the data to string format, perform public key encryption and print console.log(publicKeyEncrypt(JSON.stringify(entry), publicKey));The output content is in the following format:
(Data has been deleted)
Ri0p8QFmnYe8Xo36DextK242o9pcdL0QFDo6gUxhzjwQD30UFlqJL57na445BebSp1VT1z94emJgrME7xTDzV1tshtmVNtarqCUCzZMF4uYAtZCQLJhCX3708g7lOFksiUvi6MlXCVVOIu2VyFsIS /6DeEWYNirPK6zEBw1e2V2jWoL+63+iGNyhtKFJI1ECGyMmXUWCMicUmgE/JiHJD7YXPKB9+WaB7Wglj5udBdd4fALUp7qIo8TWJZJkLUg5yMbe7kemNWk050Xi1KiEt3s8IAqoRB1qGghTmE/TW +M/jIblSSy3Urle1AYsOFUzh9wV/H+uD+UNdaCvlvfmdV8hTIjjLNy9r/GbuaI5N0TkaX/dk47iUuorZabPoINEnM8lYxcKPvgVJufMfSX5wLxgx60nt4cpz3T2IutO97sdocVbhsiSlpFLpIk88 xd4=
3. Private key decryption
With the ciphertext encrypted by the public key, use the private key to decrypt it. The code is as follows:
const crypto = require('crypto');
/**
* Generate a public and private key pair * @return {*} publicKey: public key; privateKey: private key */
function genRSAKeyPaire() {
const { publicKey, privateKey } = crypto.generateKeyPairSync('rsa', {
modulusLength: 4096,
publicKeyEncoding: {
type: 'pkcs1',
format: 'pem',
},
privateKeyEncoding: {
type: 'pkcs1',
format: 'pem',
},
});
return { publicKey, privateKey };
}
const { publicKey, privateKey } = genRSAKeyPaire();
/**
* Use public key for encryption * @param {String} data
* @param {String} publicKey
* @return {String} encrypted ciphertext */
function publicKeyEncrypt(data, publicKey) {
return crypto.publicEncrypt(publicKey, Buffer.from(data)).toString('base64')
}
const entry = {
name: 'zhangsan',
password: '123456'
};
const encryptedData = publicKeyEncrypt(JSON.stringify(entry), publicKey);
/**
* Decrypt using private key * @param {String} encryptedData
* @param {String} privateKey
* @return {String} decrypted plaintext */
function privateKeyDecrypt(encryptedData, privateKey) {
return crypto.privateDecrypt(privateKey, Buffer.from(encryptedData, 'base64')).toString();
}
const originData = privateKeyDecrypt(encryptedData, privateKey);
//Print the data decrypted with the private key console.log(originData);Output result:
{"name":"zhangsan","password":"123456"} The content of entry data we defined above is consistent, indicating that the decryption is successful, but the decryption is a string. If the original data is an object, don't forget to deserialize it into an object.
In daily development, when it comes to front-end and back-end communication, especially important information, in order to prevent third parties from obtaining and using it, communication transmission encryption is generally performed. The most basic one is to use the https protocol, but the https protocol alone is not enough. (Easy to be hijacked and attacked by a man-in-the-middle). Therefore, the data must be encrypted at the application layer to prevent the data from being hijacked and used by others. Using asymmetric encryption can ensure that the sent ciphertext can only be decrypted by the server with the private key, thereby preventing the ciphertext from being decrypted and used by other unrelated parties. There is no absolute security in the Internet field. The only long-term solution is to continuously improve your security awareness and enhance your security skills.