Tengo el siguiente código:
const crypto = require("crypto"); const algorithm = "aes-256-gcm"; const message = "This is a secret message"; const iv = crypto.randomBytes(12); const sKey = crypto.randomBytes(32); const cipher = crypto.createCipheriv(algorithm, sKey, iv); const decipher = crypto.createDecipheriv(algorithm, sKey, iv) let encryptedData = cipher.update(message, "utf-8", "hex"); encryptedData += cipher.final("hex"); let decData = decipher.update(encryptedData, "hex", "utf-8"); decData += decipher.final("utf-8"); console.log("Encrypted message: " + encryptedData); console.log("Decrypted message: ", decData)Cuando lo ejecuto, recibo la siguiente excepción:
node:internal/crypto/cipher:193 const ret = this[kHandle].final(); ^ Error: Unsupported state or unable to authenticate data at Decipheriv.final (node:internal/crypto/cipher:193:29) at Object.<anonymous> ([...]/crypto-test.js:15:21) at Module._compile (node:internal/modules/cjs/loader:1101:14) at Object.Module._extensions..js (node:internal/modules/cjs/loader:1153:10) at Module.load (node:internal/modules/cjs/loader:981:32) at Function.Module._load (node:internal/modules/cjs/loader:822:12) at Function.executeUserEntryPoint [as runMain] (node:internal/modules/run_main:81:12) at node:internal/main/run_main_module:17:47 Se lanza un error al llamar a decipher.final() . ¿Cómo puedo arreglarlo?
Cuando utilice un cifrado autenticado (que es aes-256-gcm ), necesitará la etiqueta de autenticación del cifrado; de lo contrario Decipher.final() arrojará (como puede ver) ya que la etiqueta de autenticación que tiene (o en este caso, no) no coincide con lo que cree que es la etiqueta de autenticación del texto descifrado.
const crypto = require('crypto'); const algorithm = 'aes-256-gcm'; const message = 'This is a secret message'; const iv = crypto.randomBytes(12); const sKey = crypto.randomBytes(32); const cipher = crypto.createCipheriv(algorithm, sKey, iv); let encryptedData = cipher.update(message, 'utf-8', 'hex'); encryptedData += cipher.final('hex'); const authTag = cipher.getAuthTag().toString("hex"); // <- new console.log({authTag, encryptedData}); // for debugging const decipher = crypto.createDecipheriv(algorithm, sKey, iv); decipher.setAuthTag(Buffer.from(authTag, 'hex')); // <- new let decData = decipher.update(encryptedData, 'hex', 'utf-8'); decData += decipher.final('utf-8'); console.log('Decrypted message: ', decData)