Backend/node_modules/cryptr/index.js
2021-12-31 15:03:23 +05:30

60 lines
1.7 KiB
JavaScript

const crypto = require('crypto');
const algorithm = 'aes-256-gcm';
const ivLength = 16;
const saltLength = 64;
const tagLength = 16;
const tagPosition = saltLength + ivLength;
const encryptedPosition = tagPosition + tagLength;
function Cryptr(secret) {
if (!secret || typeof secret !== 'string') {
throw new Error('Cryptr: secret must be a non-0-length string');
}
function getKey(salt) {
return crypto.pbkdf2Sync(secret, salt, 100000, 32, 'sha512');
}
this.encrypt = function encrypt(value) {
if (value == null) {
throw new Error('value must not be null or undefined');
}
const iv = crypto.randomBytes(ivLength);
const salt = crypto.randomBytes(saltLength);
const key = getKey(salt);
const cipher = crypto.createCipheriv(algorithm, key, iv);
const encrypted = Buffer.concat([cipher.update(String(value), 'utf8'), cipher.final()]);
const tag = cipher.getAuthTag();
return Buffer.concat([salt, iv, tag, encrypted]).toString('hex');
};
this.decrypt = function decrypt(value) {
if (value == null) {
throw new Error('value must not be null or undefined');
}
const stringValue = Buffer.from(String(value), 'hex');
const salt = stringValue.slice(0, saltLength);
const iv = stringValue.slice(saltLength, tagPosition);
const tag = stringValue.slice(tagPosition, encryptedPosition);
const encrypted = stringValue.slice(encryptedPosition);
const key = getKey(salt);
const decipher = crypto.createDecipheriv(algorithm, key, iv);
decipher.setAuthTag(tag);
return decipher.update(encrypted) + decipher.final('utf8');
};
}
module.exports = Cryptr;