Files
Ausweis/frontend/js-encryption/decrypt.js
2023-10-02 23:39:20 +02:00

14 lines
566 B
JavaScript

async function decrypt(ciphertext, password) {
const pwUtf8 = new TextEncoder().encode(password);
const pwHash = await crypto.subtle.digest('SHA-256', pwUtf8);
const ctUtf8 = new Uint8Array(Array.from(atob(ciphertext)).map(x => x.charCodeAt(0)));
const alg = { name: 'AES-GCM', iv: ctUtf8.slice(0,12) };
const key = await crypto.subtle.importKey('raw', pwHash, alg, false, ['decrypt']);
try {
const buf = await crypto.subtle.decrypt(alg, key, ctUtf8.slice(12));
return new TextDecoder().decode(buf);
} catch (e) {
throw new Error('Decrypt failed')
}
}