Using node-jose, how do I decrypt the data I just encrypted? - javascript

I am trying to implement simple JOSE encrypt and decrypt functions using node-jose.
My code is as follows (written using Node 8.2.1)
const { JWE } = require('node-jose');
const jose = (publicKey, privateKey) => {
async function encrypt(raw) {
if (!raw) throw new Error('Missing raw data.')
const buffer = new Buffer(JSON.stringify(raw));
return JWE.createEncrypt(publicKey).update(buffer).final();
}
async function decrypt(encrypted) {
if (!encrypted) throw new Error('Missing encrypted data.')
const buffer = new Buffer(JSON.stringify(encrypted));
return JWE.createDecrypt(privateKey).decrypt(buffer);
}
return { encrypt, decrypt }
}
module.exports = jose;
I generate an RSA keypair using generate-rsa-keypair.
So testing via this code the encryption side of things works fine
const { JWK } = require('node-jose');
const keygen = require('generate-rsa-keypair');
const jose = require('./src/utils/jose');
const rawKeys = keygen();
const makeKey = pem => JWK.asKey(pem, 'pem');
async function start() {
const publicKey = await makeKey(rawKeys.public)
const privateKey = await makeKey(rawKeys.private)
const raw = {
iss: 'test',
exp: new Date().getTime() + 3600,
sub: {
test: 'This is a test',
},
};
const { encrypt, decrypt } = jose(publicKey, privateKey);
return encrypt(raw).then(encrypted => decrypt(encrypted));
}
return start().then((result) => {
console.log('decrypted', result)
}, (err) => {
console.error(err);
});
the encrypted result is
{
recipients: [ { encrypted_key: 'ciNiK6Unq30zCAXxIl2Dx9b8bZAi79qbpL1yUCwTFnSghFLrIZ11_D2ozt5on3r3ThUu96oDLZPcNShbqWPMV49NvQAsSNGdemhgzmTt3Lf3rJn1YiqvJvqf5NIXdmzjdoEZi-d9224mGpZGVKtIIFeT6-0hYgm5zNqq_aF_X2jy5IiF-mAGspNdXIk_KXPrTVbnU-XL9J5aAoG2Lp51Te1WzGA4Fjg4Ve5ZTzH6TLlQ5R5Ob_14liK-INrSi3armwXrtMgJcTmI_4oBtORtZp8AjaXzecFO_GzifvRVCSKx2vmpy9KaECpskMhZBHVx9RX9cvGKh7hq3Y7vsUucZw' } ],
protected: 'eyJhbGciOiJSU0EtT0FFUCIsImtpZCI6IldLWS1ONDRXM2RnanA4U2ZxSlp3TldqV3AzUG1XZ29UczhjRDh3eWNSUWciLCJlbmMiOiJBMTI4Q0JDLUhTMjU2In0',
iv: 'wvqir2ewtQPfDHQtzl6IUg',
ciphertext: 'ZwIrL_3739LI17rh3gWDUA6lXIL7ewkSh54FO_RwumC0qh9B0DcAr8RyXsfPbW19cV4u7SbZNSRP6B8qNOTy-2iENlqBISfE_kolDt8g5sg',
tag: 'z8nwrJfRgOi1hYMBI9lGeQ'
}
but when I try to decrypt that I get
Error: no key found
at processKey (node_modules/node-jose/lib/jwe/decrypt.js:157:22)
There are very few examples of using node-jose so I am unsure of the following
I am assuming I ought to be decrypting with the private key. But that's just an assumption. None of the examples show use of public/private key pairs, just a single key.
I'm assuming that the results of the encryption can just be strringified and turned into a buffer and passed into decrypt but perhaps that's not the case.
How does this really work?

When using public/private key pairs, the private key is used to decrypt and the public key is used to encrypt.
The input to JWEDecrypter.decrypt() is the promised output from JWEEncrypter.final().
Change your decrypt function to:
async function decrypt(encrypted) {
if (!encrypted) throw new Error('Missing encrypted data.')
return JWE.createDecrypt(privateKey).decrypt(encrypted);
}

Related

How to properly decrypt string in NodeJS?

I'm working on a NodeJS & MongoDB project where it is required to encrypt the content of the article that it is about to be published.
However, it should display the content if the proper key-codes are entered.
For example, I have a function to create blog where I call my encryText() function:
exports.createBlog = asyncHandler(async (req, res, next) => {
if (req.body.text === ``) {
return next(new ErrorResponse(`Please add some text`, 500));
}
// Encrypt text
req.body.text = encrypText(req.body.text); // The data gets encrypted
// Create document
const blog = await Blog.create(req.body);
blog.save({ validateBeforeSave: true });
// Send response
res.status(201).json({ success: true, data: blog });
});
This encrypText() function returns an object that looks like this:
{
"success": true,
"data": {
"iv": "QkBZfnTyqaofnHbDC4y6Iw==",
"encryptedData": "ebe177048b1063acae4eea3b5303a56b62da0ef7c3fc537b4245cf0cbee0291bf4231d0eb97c53e0c0c33fce50f26561277c25829f7021bbc1532aed6e4dc782"
}
}
Now, nothing is wrong so far. The encryption works great and the decryption also works amazingly well also. The way to decrypt data is by using the same object returned from the encryptText() function and it does as expected but only during few minutes!.
"status": "error",
"error": {
"library": "digital envelope routines",
"function": "EVP_DecryptFinal_ex",
"reason": "bad decrypt",
"code": "ERR_OSSL_EVP_BAD_DECRYPT",
"statusCode": 500,
"status": "error"
},
"message": "error:06065064:digital envelope routines:EVP_DecryptFinal_ex:bad decrypt",
As you can see, the error gets thrown on my screen after 5mins and/or whenever I reset the server.! Why is it that this happens? I mean the string that I'm trying to decrypt has not changed at all?
const crypto = require('crypto');
// Set encryption algorith
const algorithm = 'aes-256-cbc';
/// Private key
const key = crypto.randomBytes(32);
// Random 16 digit initialization vector
const iv = crypto.randomBytes(16);
exports.encrypText = (text) => {
const cipher = crypto.createCipheriv(algorithm, key, iv);
let encryptedData = cipher.update(text, 'utf-8', 'hex');
encryptedData += cipher.final('hex');
// convert the initialization vector to base64 string
const base64data = Buffer.from(iv, 'binary').toString('base64');
return {
iv: base64data,
encryptedData: encryptedData
};
};
exports.decrypText = (text) => {
// Convert initialize vector from base64 to buffer
const originalData = Buffer.from(text.iv, 'base64');
// Decrypt the string using encryption algorith and private key
const decipher = crypto.createDecipheriv(algorithm, key, originalData);
let decryptedData = decipher.update(text.encryptedData, 'hex', 'utf-8');
decryptedData += decipher.final('utf-8');
return decryptedData;
};
Solved it by making a my secret key static and also went into a different approach which does exactly what I wanted.
const crypto = require('crypto');
// Set encryption algorith
const algorithm = 'aes-256-ctr';
/// Private key
// const key = crypto.randomBytes(32);
const key = `${process.env.ENCRYPTION_KEY}`;
// Random 16 digit initialization vector
const iv = crypto.randomBytes(16);
exports.encrypText = (text) => {
const cipher = crypto.createCipheriv(algorithm, key, iv);
const encryptedData = Buffer.concat([cipher.update(text), cipher.final()]);
return {
iv: iv.toString('hex'),
encryptedData: encryptedData.toString('hex')
};
};
exports.decrypText = (text) => {
// Convert initialize vector from base64 to hex
const originalData = Buffer.from(text.iv, 'hex');
// Decrypt the string using encryption algorith and private key
const decipher = crypto.createDecipheriv(algorithm, key, originalData);
const decryptedData = Buffer.concat([
decipher.update(Buffer.from(text.encryptedData, 'hex')),
decipher.final()
]);
return decryptedData.toString();
};

Encrypt on PHP and Decrypt on Javascript

Recently I am trying to find a way to encrypt data on PHP with a Public Key generated on javascript using window.crypto.subtle.generateKey()
async function GenerateKeys() {
let key = await window.crypto.subtle.generateKey(
{
name: "RSA-OAEP",
modulusLength: 4096,
publicExponent: new Uint8Array([0x01, 0x00, 0x01]),
hash: {name: "SHA-256"}
},
true,
["encrypt", "decrypt"]
)
let pvkey = await window.crypto.subtle.exportKey(
"pkcs8",
key.privateKey
)
let pbkey = await window.crypto.subtle.exportKey(
"spki",
key.publicKey
)
let pemPvKey = `-----BEGIN PRIVATE KEY-----\n${window.btoa(ab2str(pvkey))}\n-----END PRIVATE KEY-----`;
let pemPbKey = `-----BEGIN PUBLIC KEY-----\n${window.btoa(ab2str(pbkey))}\n-----END PUBLIC KEY-----`;
return [pemPvKey, pemPbKey]
}
I then send the public key to my PHP script and generate data
$pbkey = "-----BEGIN PUBLIC KEY-----
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
-----END PUBLIC KEY-----";
openssl_public_encrypt("secret", $encrypted, $pbkey, OPENSSL_PKCS1_OAEP_PADDING );
echo base64_encode($encrypted);
Finally, I use the generated cipher on javascript by using decrypt function (the key is stored in localstorage btw in pkcs8 format)
function FormatPrivateKey(pemPvKey) {
return pemPvKey.replace("-----BEGIN PRIVATE KEY-----", "").replace("-----END PRIVATE KEY-----", "").replace(/[\r\n]/gm, "");
}
function GetKeys() {
const pvkey = localStorage.getItem("pvkey");
const pbkey = localStorage.getItem("pbkey");
return [pvkey, pbkey]
}
async function Decrypt(message) {
const keys = GetKeys();
let pemPvKey = keys[0];
const pvkey = await window.crypto.subtle.importKey(
"pkcs8",
str2ab(window.atob(FormatPrivateKey(pemPvKey))),
{
name: "RSA-OAEP",
hash: {name: "SHA-256"}
},
false,
["decrypt"]
);
return await window.crypto.subtle.decrypt(
{
name: "RSA-OAEP"
},
pvkey,
str2ab(window.atob(message))
);
}
When I try to decrypt the data, I receive this error:
Uncaught DOMException: The operation failed for an operation-specific reason
I do not know why this happens.
PHP/OpenSSL only supports OAEP with SHA1 for both digests, see here.
So to decrypt the ciphertext generated with PHP OpenSSL, SHA-1 must be specified in Decrypt() or more precisely in importKey() instead of SHA-256.
Consequently, SHA-1 should also be specified in the key generation. However, this is not mandatory because of the export/reimport. It would be necessary if the generated private key was used directly (i.e. without reimport) for decryption, which is not the case in this scenario.
In the example below, I generated the keys with the unmodified JavaScript code and the ciphertext with the PHP code. The decryption is successful when using the described bugfix.
(async () => {
async function Decrypt(message) {
const keys = GetKeys();
let pemPvKey = keys[0];
const pvkey = await window.crypto.subtle.importKey(
"pkcs8",
str2ab(window.atob(FormatPrivateKey(pemPvKey))),
{
name: "RSA-OAEP",
hash: {name: "SHA-1"} // Fix!
},
false,
["decrypt"]
);
return await window.crypto.subtle.decrypt(
{
name: "RSA-OAEP"
},
pvkey,
str2ab(window.atob(message))
);
}
function GetKeys() {
const pvkey = `-----BEGIN PRIVATE KEY-----
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
-----END PRIVATE KEY-----`;//localStorage.getItem("pvkey");
const pbkey = "";//localStorage.getItem("pbkey");
return [pvkey, pbkey]
}
function FormatPrivateKey(pemPvKey) {
return pemPvKey.replace("-----BEGIN PRIVATE KEY-----", "").replace("-----END PRIVATE KEY-----", "").replace(/[\r\n]/gm, "");
}
// https://stackoverflow.com/a/11058858
function str2ab(str) {
const buf = new ArrayBuffer(str.length);
const bufView = new Uint8Array(buf);
for (let i = 0, strLen = str.length; i < strLen; i++) {
bufView[i] = str.charCodeAt(i);
}
return buf;
}
function ab2str(buf) {
return String.fromCharCode.apply(null, new Uint8Array(buf));
}
var ciphertext = "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";
console.log(ab2str(await Decrypt(ciphertext)));
})();
To use OAEP with SHA-256 on the PHP side phpseclib is an option.

node-jose cyrillic support, how to?

https://github.com/cisco/node-jose
it's my code example:
let keystore1;
let keystore2;
keystore1 = JWK.createKeyStore();
keystore2 = JWK.createKeyStore();
const input = { message: { text: 'Привет!' } };
const priv1 = await keystore1.generate('EC', 'P-256', {
kid: '1gBdaS-G8RLax2qgObTD94w',
key_ops:["sign", "decrypt", "unwrap"]
});
const priv2 = await keystore2.generate('EC', 'P-256', {
kid: '2gBdaS-G8RLax2qgObTD94v',
key_ops:["sign", "decrypt", "unwrap"]
});
const pub1 = await JWK.asKey(priv1.toJSON());
const pub2 = await JWK.asKey(priv2.toJSON());
const encrypted = await JWE.createEncrypt(
{
format: 'compact',
fields: {
alg: 'ECDH-ES',
enc: 'A128CBC-HS256',
cty: 'json', // replace with JWT if you're encrypting a JWT...
},
},
{
key: pub2,
}
)
.update(JSON.stringify(input))
.final();
console.log('encrypted', encrypted);
const decrypted = await JWE.createDecrypt(priv2).decrypt(encrypted);
console.log('decrypted', JSON.parse(decrypted.payload.toString()));
// simulate only having access to the public key, usually this is your starting point as you only have access to the public components if you're encrypting a message for someone else.
With latin - decryption ok!
How to decrypte with cyrillic, please help me.
You can pass the encoding to the update function.
e.g.JWE.createEncrypt(...).update(input, "utf8")
Doc

Decrypt an RSA message from browser with window.crypto.subtle APIs

I'm trying to decode an RSA 2048 bit message encoded with a public key using the corresponding private key. The environment is google chrome and I'm using the window.crypto.subtle APIs.
I generated the key couple and encoded the message using openssl tools:
# generate keys and put the private one in file private_key.pem
openssl genpkey -algorithm RSA -out private_key.pem -pkeyopt rsa_keygen_bits:2048
# extract public key in file public_key.pem
openssl rsa -pubout -in private_key.pem -out public_key.pem
# encode message input.txt using the public key
openssl rsautl -encrypt -oaep -inkey public_key.pem -pubin -in input.txt -out msg_rsa.enc
# convert the encoded msg in base 64 format
base64 msg_rsa.enc > msg_rsa_64.enc
This is the javascript code I'm using to decode the message:
function str2ab(str) {
const buf = new ArrayBuffer(str.length);
const bufView = new Uint8Array(buf);
for (let i = 0, strLen = str.length; i < strLen; i++) {
bufView[i] = str.charCodeAt(i);
}
return buf;
}
async function importPrivateKey(pem) {
pem = pem.replace( /[\r\n]+/gm, "" );
// fetch the part of the PEM string between header and footer
const pemHeader = "-----BEGIN PRIVATE KEY-----";
const pemFooter = "-----END PRIVATE KEY-----";
const pemContents = pem.substring(pemHeader.length, pem.length - pemFooter.length);
// base64 decode the string to get the binary data
const binaryDerString = window.atob(pemContents);
// convert from a binary string to an ArrayBuffer
const binaryDer = str2ab(binaryDerString);
return window.crypto.subtle.importKey(
"pkcs8",
binaryDer,
{
name: "RSA-OAEP",
modulusLength: 2048,
publicExponent: new Uint8Array([1, 0, 1]),
hash: "SHA-256",
},
true,
["decrypt"]
);
}
async function decryptRSA(_key, ciphertext) {
let decrypted = await window.crypto.subtle.decrypt(
{
name: "RSA-OAEP"
},
_key,
ciphertext
);
const dec = new TextDecoder();
return dec.decode(decrypted);
}
const fromBase64 = base64String => Uint8Array.from(atob(base64String), c => c.charCodeAt(0));
window.onload = init;
async function init() {
const privateKey = '-----BEGIN PRIVATE KEY-----\
MIIEvwIBADANBgkqhkiG9w0BAQEFAASCBKkwggSlAgEAAoIBAQC3jmTi3O1k2YXs\
AM6nNTTIzDq5YWkxYrYb6cpO9eYuzmphgRnVDR6a1YWRXMoCuCfuNXcDGywzudRn\
bBMw0FHKLUqCttVHGpZYu0+0tRR10ubxiz/xnd/aCmRYHcmUNn8Qdh3KU59A9HK5\
HhYFf1vhK8r3fkoO4CjoGo1ROzXyMybUSy+4mSNscUtt5LwrVn48vXvG5i5B4DRT\
nM4cINmutEzA2s5cDt+dzU4Py71fKBRDRIGGn0vdVSoZKbWuhm5WewyRewCk7HFc\
PALCi5/1A7VKDAHUC4FlXmuG2+wzdchEyxMj6oLR7+BkKFQaTmuMM/22cGBjVTVt\
pSr3iDovAgMBAAECggEBAIuTQW+oovNu3IDq1DkdIjgV5AmW4tBkySlMi0OjhBbP\
auEdtDDnOwBtoJU6Q3nx4psmGItKHEBw6+yAp88UeT0NV30x3delhfGO7Trx/s7h\
Qi8lvcfSTqeUA11luSR0lAZGaryw/YX820eccw5XG9yK2ll7tIC/PxvPJOpB5fF2\
XGxGrionTjHDzXJ1OWX0i0aZlNNufInJAHhlt7aT3GiQMKcQs+AUb/+bWxI3Hln8\
KcL13EUlD4pJW8vtTK3gCnQNKKMoPB5Ugqe5BrU8ElkBz+zSKDnVwt5bgjrlucYz\
rKJxWr6/qTRZkzmvkhaJeNzzepfwkFsQ/eHcxYrtuDECgYEA8OXkQ2SqYDZwizCd\
SuVkx2zHm3zXYRSlRtnXYoUdJyTyuZ4k2GvXBrlwRsOJ14emVkHKyR5enmNjwrW5\
dcD2tbBzavcqOYAMiHcKklcS/gWgPx0X5QFHU33vr8u51BQWCz75lxddWNKxVAN/\
cUTugONtS4+EP4dSZhuxHt6RscsCgYEAwxA9QmZrI54hjMkIyqwmviRmIk42S5kk\
OxbhxBbt5qVueLRB092JyGmCR2kYiqdHCYkGFDOE4kni6Bsszq5CSJvhiATFeZeX\
ldFQeZqAiRY2rAd7xD1upMug/cK3ODA8k3k/e72CtyxtBTR01q29SnPx5p/57MrI\
3ogddHlGvK0CgYEA3VqhELwjQh1D9OJK5lM683SlRd7FGdOauyvYmhKu4xU0ZBNI\
0ATnpKoo3R04P+/JjGEQMRXS4794H6ZUMDuLdxAYPiW3ivZ6jbq04BtavEf3I4dc\
OXWfULzbzbFpo9KBHvxS4974S3Hut8AvDqnEbnKML25EmwuBT4oKis8BGVkCgYEA\
nusPDZbFeNou+TUbzYrdcZHUB+TyhTq58s4clxYbMgrbaslozAQ0aavT8Pvle6j2\
zgTth+3FOFr72x+wrJ358I/W+Wrxu7NOU0eZqci/KXCIkDT0l5d5GhewDK3jeYqK\
/5cLqnNmGHfARjpLak9X5V162erBwjIf3nTEkozvnW0CgYB6L1CX3DkTFH3OBcJe\
SvV18RDUfNI8MpUKcpofmwwvgER3GrehSZHRVxVwNbnJOqbh/oiwmmNJieKrFsk9\
EzCRBVWdZByHHYW2js+gCrAp+ghnl1QEAeCU7YTxCJ2fZIAmfB9X4u/7ARtVxnZY\
mOWlm65KUYr5lf2Ws5plL4pCRA==\
-----END PRIVATE KEY-----';
const ciphertext = 'F6/NwENdUZSl+vrgpWVkyWPQuYaTGDNZPIvj4KmIRHVx4qybxN24LPIgk0Rl84KHcLFadZWCjNpM\
vg3l826OaKZAtwvIp9IxVrMbvtNOymY6A1koKvC9ema92SR4DC9hmTtMxhUB6r3XgACtRLFqMfg+\
zYSHfFqQEGJg3yZ43hfzIq/gCfHPk5sZXASq5WY5b9yd4gRonn5D4OCD6xna/r5ovHfrpO/Fwe8N\
eeY2gqTAdtzvtmOw/HLQhGANejpJYr1IriQbepM7jLjBkJX+uCn38O1MxpQb7s5RXTvGvoEoofWV\
Cq8gNFhgnVFuurdZUiY0bn58UwaVFdwzEfDSUQ==';
try {
const key = await importPrivateKey(privateKey);
const decoded = await decryptRSA(key, fromBase64(ciphertext));
console.log(decoded);
} catch(error) {
console.log(error);
}
}
Running the code, I got an exception in window.crypto.subtle.decrypt with the rather useless message "DOMException".
What am I doing wrong?
Thanks
There's only one flaw: The posted code currently uses OAEP with SHA256. The ciphertext can be decrypted with the posted key if OAEP with SHA1 is applied as padding.
In addition, the function fromBase64 can be used to Base64 decode the key into a TypedArray, so the function str2ab is actually not needed (but of course this is not an error, just redundant).
const fromBase64 = base64String => Uint8Array.from(atob(base64String), c => c.charCodeAt(0));
const getPkcs8Der = pkcs8Pem => {
pkcs8Pem = pkcs8Pem.replace( /[\r\n]+/gm, "" );
const pkcs8PemHeader = "-----BEGIN PRIVATE KEY-----";
const pkcs8PemFooter = "-----END PRIVATE KEY-----";
pkcs8Pem = pkcs8Pem.substring(pkcs8PemHeader.length, pkcs8Pem.length - pkcs8PemFooter.length);
return fromBase64(pkcs8Pem);
}
async function importPrivateKey(pkcs8Pem) {
return await window.crypto.subtle.importKey(
"pkcs8",
getPkcs8Der(pkcs8Pem),
{
name: "RSA-OAEP",
hash: "SHA-1", // Replace SHA-256 with SHA-1
},
true,
["decrypt"]
);
}
async function decryptRSA(key, ciphertext) {
let decrypted = await window.crypto.subtle.decrypt(
{
name: "RSA-OAEP"
},
key,
ciphertext
);
const dec = new TextDecoder();
return dec.decode(decrypted);
}
window.onload = init;
async function init() {
const privateKey =
'-----BEGIN PRIVATE KEY-----\
MIIEvwIBADANBgkqhkiG9w0BAQEFAASCBKkwggSlAgEAAoIBAQC3jmTi3O1k2YXs\
AM6nNTTIzDq5YWkxYrYb6cpO9eYuzmphgRnVDR6a1YWRXMoCuCfuNXcDGywzudRn\
bBMw0FHKLUqCttVHGpZYu0+0tRR10ubxiz/xnd/aCmRYHcmUNn8Qdh3KU59A9HK5\
HhYFf1vhK8r3fkoO4CjoGo1ROzXyMybUSy+4mSNscUtt5LwrVn48vXvG5i5B4DRT\
nM4cINmutEzA2s5cDt+dzU4Py71fKBRDRIGGn0vdVSoZKbWuhm5WewyRewCk7HFc\
PALCi5/1A7VKDAHUC4FlXmuG2+wzdchEyxMj6oLR7+BkKFQaTmuMM/22cGBjVTVt\
pSr3iDovAgMBAAECggEBAIuTQW+oovNu3IDq1DkdIjgV5AmW4tBkySlMi0OjhBbP\
auEdtDDnOwBtoJU6Q3nx4psmGItKHEBw6+yAp88UeT0NV30x3delhfGO7Trx/s7h\
Qi8lvcfSTqeUA11luSR0lAZGaryw/YX820eccw5XG9yK2ll7tIC/PxvPJOpB5fF2\
XGxGrionTjHDzXJ1OWX0i0aZlNNufInJAHhlt7aT3GiQMKcQs+AUb/+bWxI3Hln8\
KcL13EUlD4pJW8vtTK3gCnQNKKMoPB5Ugqe5BrU8ElkBz+zSKDnVwt5bgjrlucYz\
rKJxWr6/qTRZkzmvkhaJeNzzepfwkFsQ/eHcxYrtuDECgYEA8OXkQ2SqYDZwizCd\
SuVkx2zHm3zXYRSlRtnXYoUdJyTyuZ4k2GvXBrlwRsOJ14emVkHKyR5enmNjwrW5\
dcD2tbBzavcqOYAMiHcKklcS/gWgPx0X5QFHU33vr8u51BQWCz75lxddWNKxVAN/\
cUTugONtS4+EP4dSZhuxHt6RscsCgYEAwxA9QmZrI54hjMkIyqwmviRmIk42S5kk\
OxbhxBbt5qVueLRB092JyGmCR2kYiqdHCYkGFDOE4kni6Bsszq5CSJvhiATFeZeX\
ldFQeZqAiRY2rAd7xD1upMug/cK3ODA8k3k/e72CtyxtBTR01q29SnPx5p/57MrI\
3ogddHlGvK0CgYEA3VqhELwjQh1D9OJK5lM683SlRd7FGdOauyvYmhKu4xU0ZBNI\
0ATnpKoo3R04P+/JjGEQMRXS4794H6ZUMDuLdxAYPiW3ivZ6jbq04BtavEf3I4dc\
OXWfULzbzbFpo9KBHvxS4974S3Hut8AvDqnEbnKML25EmwuBT4oKis8BGVkCgYEA\
nusPDZbFeNou+TUbzYrdcZHUB+TyhTq58s4clxYbMgrbaslozAQ0aavT8Pvle6j2\
zgTth+3FOFr72x+wrJ358I/W+Wrxu7NOU0eZqci/KXCIkDT0l5d5GhewDK3jeYqK\
/5cLqnNmGHfARjpLak9X5V162erBwjIf3nTEkozvnW0CgYB6L1CX3DkTFH3OBcJe\
SvV18RDUfNI8MpUKcpofmwwvgER3GrehSZHRVxVwNbnJOqbh/oiwmmNJieKrFsk9\
EzCRBVWdZByHHYW2js+gCrAp+ghnl1QEAeCU7YTxCJ2fZIAmfB9X4u/7ARtVxnZY\
mOWlm65KUYr5lf2Ws5plL4pCRA==\
-----END PRIVATE KEY-----';
const ciphertext =
'F6/NwENdUZSl+vrgpWVkyWPQuYaTGDNZPIvj4KmIRHVx4qybxN24LPIgk0Rl84KHcLFadZWCjNpM\
vg3l826OaKZAtwvIp9IxVrMbvtNOymY6A1koKvC9ema92SR4DC9hmTtMxhUB6r3XgACtRLFqMfg+\
zYSHfFqQEGJg3yZ43hfzIq/gCfHPk5sZXASq5WY5b9yd4gRonn5D4OCD6xna/r5ovHfrpO/Fwe8N\
eeY2gqTAdtzvtmOw/HLQhGANejpJYr1IriQbepM7jLjBkJX+uCn38O1MxpQb7s5RXTvGvoEoofWV\
Cq8gNFhgnVFuurdZUiY0bn58UwaVFdwzEfDSUQ==';
try {
const key = await importPrivateKey(privateKey);
const decrypted = await decryptRSA(key, fromBase64(ciphertext));
console.log(decrypted);
} catch(error) {
console.log(error);
}
}

NodeJS crypto module: clean cipher reuse

I'm a bit new to the crypto module in Node. I wrote an encryption function that works perfectly fine but looks awful. This there a better way to write this?
const encrypt = data => {
const iv = crypto.randomBytes(16);
const key = crypto.randomBytes(32).toString('hex').slice(0, 32);
const cipher1 = crypto.createCipheriv(algorithm, new Buffer(key), iv);
const cipher2 = crypto.createCipheriv(algorithm, new Buffer(key), iv);
const cipher3 = crypto.createCipheriv(algorithm, new Buffer(key), iv);
const encryptedFile = Buffer.concat([cipher1.update(data.file), cipher1.final()]);
const encryptedFileName = Buffer.concat([cipher2.update(data.fileName), cipher2.final()]).toString('hex');
const encryptedId = Buffer.concat([cipher3.update(data.Id), cipher3.final()]).toString('hex');
return {
file: encryptedFile,
fileName: encryptedFileName,
id: iv.toString('hex') + ':' + encryptedId.toString('hex'),
key
};
};
Input is an object of this structure:
{
file: <Buffer>,
fileName: <String>,
Id: <String>
}
I need to encrypt all of the values with the same key + iv, but not the whole object at once. Is there a way to refactor this to avoid duplication?
Try this:
const encrypt = (data, key, iv) => {
const cipher = crypto.createCipheriv(algorithm, new Buffer(key), iv);
return Buffer.concat([cipher.update(data), cipher.final()]);
};
const encrypt = data => {
const iv = crypto.randomBytes(16);
const key = crypto
.randomBytes(32)
.toString('hex')
.slice(0, 32);
return {
file: encrypt(data.file, key, iv),
fileName: encrypt(data.fileName, key, iv).toString('hex'),
id: `${iv.toString('hex')}:${encrypt(data.Id, key, iv).toString('hex')}`,
key,
};
};

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