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@yoavniran
Last active January 20, 2022 08:16
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nodejs crypto - simple encrypt & decrypt using IV (Initialization Vector)
"use strict";
var crypto = require("crypto");
var EncryptionHelper = (function () {
function getKeyAndIV(key, callback) {
crypto.pseudoRandomBytes(16, function (err, ivBuffer) {
var keyBuffer = (key instanceof Buffer) ? key : new Buffer(key) ;
callback({
iv: ivBuffer,
key: keyBuffer
});
});
}
function encryptText(cipher_alg, key, iv, text, encoding) {
var cipher = crypto.createCipheriv(cipher_alg, key, iv);
encoding = encoding || "binary";
var result = cipher.update(text, "utf8", encoding);
result += cipher.final(encoding);
return result;
}
function decryptText(cipher_alg, key, iv, text, encoding) {
var decipher = crypto.createDecipheriv(cipher_alg, key, iv);
encoding = encoding || "binary";
var result = decipher.update(text, encoding);
result += decipher.final();
return result;
}
return {
CIPHERS: {
"AES_128": "aes128", //requires 16 byte key
"AES_128_CBC": "aes-128-cbc", //requires 16 byte key
"AES_192": "aes192", //requires 24 byte key
"AES_256": "aes256" //requires 32 byte key
},
getKeyAndIV: getKeyAndIV,
encryptText: encryptText,
decryptText: decryptText
};
})();
module.exports = EncryptionHelper;
var encryptionHelper = require("./simple-nodejs-iv-encrypt-decrypt.js")
var story = "this is the story of the brave prince who went off to fight the horrible dragon... he set out on his quest one sunny day";
var algorithm = encryptionHelper.CIPHERS.AES_256;
console.log("testing encryption and decryption");
console.log("text is: " + story);
encryptionHelper.getKeyAndIV("1234567890abcdefghijklmnopqrstuv", function (data) { //using 32 byte key
console.log("got key and iv buffers");
var encText = encryptionHelper.encryptText(algorithm, data.key, data.iv, story, "base64");
console.log("encrypted text = " + encText);
var decText = encryptionHelper.decryptText(algorithm, data.key, data.iv, encText, "base64");
console.log("decrypted text = " + decText);
assert.equal(decText, story);
});
@GiovanniCapizzi
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Can you use Buffer.from(key) instead, due to its deprecation?

@System-D
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System-D commented Dec 6, 2018

Yes if you have following message : DeprecationWarning: Buffer() is deprecated due to security and usability issues. Please use the Buffer.alloc(), Buffer.allocUnsafe(), or Buffer.from() methods instead.

You can use Buffer.from(key) instead new Buffer(key)
But it's working only for variable contenting a string

For variable contenting a number you can change : new Buffer(num) to Buffer.alloc(num)

@ppbntl19
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ppbntl19 commented Jun 9, 2020

//CryptoJS example

var key = "H98zM6i/55yNJfkFsbu0HrzlFo17FtR9";
var iv = key.slice(0, 16);
//Create Key
key = CryptoJS.enc.Utf8.parse(key);
//Get Iv
iv = CryptoJS.enc.Utf8.parse(iv);
var encrypted = CryptoJS.AES.encrypt("testtest", key,{ iv: iv});
//Encrypt string
var encrypted_data = encrypted.toString();

console.log(encrypted_data)

var decrypted = CryptoJS.AES.decrypt(encrypted_data, key,{ iv: iv});
var decrypted_data = decrypted.toString(CryptoJS.enc.Utf8)

console.log(decrypted_data)

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