@transcend-io/lazydecipheriv

Lazy Decipheriv

createDecipheriv, but setAuthTag later.

Problem: In Node, it's required to decipher.setAuthTag() before beginning a decipher stream.

Usage

const createLazyDecipheriv = require('@transcend-io/lazydecipheriv');
const decipher = createLazyDecipheriv('aes-256-gcm', key, iv);

await pipeline(
  readable,
  decipher,
  writable,
);

decipher.setAuthTag(authTag);
console.log(decipher.isAuthenticated); // => true

Error handling invalid authentications tags

An invalid authTag passed to decipher.setAuthTag() will throw the same error that decipher.final() would. If the authTag is set before the decipher is finished, then the stream will throw when it is done. You can also check decipher.isAuthenticated to see if the integrity check has passed yet.