Tyler
105 lines
3.1 KiB
JavaScript
105 lines
3.1 KiB
JavaScript
/**
|
|
* Encryption module.
|
|
* Handles cryptographic operations using Web Crypto API.
|
|
* Implements AES-GCM encryption with PBKDF2 key derivation.
|
|
*/
|
|
|
|
// ===== Constants =====
|
|
const SALT_LENGTH = 16;
|
|
const IV_LENGTH = 12;
|
|
const PBKDF2_ITERATIONS = 200_000;
|
|
const KEY_LENGTH = 256;
|
|
|
|
// ===== Key Derivation =====
|
|
/**
|
|
* Derives an AES-GCM key from a password using PBKDF2.
|
|
* @param {string} password - User-supplied password.
|
|
* @param {Uint8Array} salt - Randomly generated salt.
|
|
* @returns {Promise<CryptoKey>} - Derived cryptographic key.
|
|
*/
|
|
export async function deriveKey(password, salt) {
|
|
const encoder = new TextEncoder();
|
|
const keyMaterial = await crypto.subtle.importKey(
|
|
'raw',
|
|
encoder.encode(password),
|
|
{ name: 'PBKDF2' },
|
|
false,
|
|
['deriveKey']
|
|
);
|
|
|
|
return crypto.subtle.deriveKey(
|
|
{
|
|
name: 'PBKDF2',
|
|
salt,
|
|
iterations: PBKDF2_ITERATIONS,
|
|
hash: 'SHA-256'
|
|
},
|
|
keyMaterial,
|
|
{ name: 'AES-GCM', length: KEY_LENGTH },
|
|
false,
|
|
['encrypt', 'decrypt']
|
|
);
|
|
}
|
|
|
|
// ===== Encryption =====
|
|
/**
|
|
* Encrypts a message using AES-GCM with a derived key.
|
|
* @param {string} message - Plaintext message to encrypt.
|
|
* @param {string} password - User password for key derivation.
|
|
* @returns {Promise<string>} - Base64-encoded encrypted string.
|
|
*/
|
|
export async function encryptAdvanced(message, password) {
|
|
const encoder = new TextEncoder();
|
|
const salt = crypto.getRandomValues(new Uint8Array(SALT_LENGTH));
|
|
const iv = crypto.getRandomValues(new Uint8Array(IV_LENGTH));
|
|
const key = await deriveKey(password, salt);
|
|
const encoded = encoder.encode(message);
|
|
|
|
const ciphertext = await crypto.subtle.encrypt(
|
|
{ name: 'AES-GCM', iv },
|
|
key,
|
|
encoded
|
|
);
|
|
|
|
const output = new Uint8Array(salt.length + iv.length + ciphertext.byteLength);
|
|
output.set(salt);
|
|
output.set(iv, salt.length);
|
|
output.set(new Uint8Array(ciphertext), salt.length + iv.length);
|
|
|
|
return btoa(String.fromCharCode(...output));
|
|
}
|
|
|
|
// ===== Decryption =====
|
|
/**
|
|
* Decrypts an AES-GCM encrypted string.
|
|
* @param {string} encryptedData - Base64-encoded ciphertext.
|
|
* @param {string} password - Password used to derive the decryption key.
|
|
* @returns {Promise<string>} - Decrypted plaintext.
|
|
*/
|
|
export async function decryptAdvanced(encryptedData, password) {
|
|
const encrypted = new Uint8Array(
|
|
atob(encryptedData).split('').map(c => c.charCodeAt(0))
|
|
);
|
|
|
|
const salt = encrypted.slice(0, SALT_LENGTH);
|
|
const iv = encrypted.slice(SALT_LENGTH, SALT_LENGTH + IV_LENGTH);
|
|
const ciphertext = encrypted.slice(SALT_LENGTH + IV_LENGTH);
|
|
const key = await deriveKey(password, salt);
|
|
|
|
const decrypted = await crypto.subtle.decrypt(
|
|
{ name: 'AES-GCM', iv },
|
|
key,
|
|
ciphertext
|
|
);
|
|
|
|
return new TextDecoder().decode(decrypted);
|
|
}
|
|
|
|
// ===== Module Initialization =====
|
|
/**
|
|
* Initializes the encryption module and logs its status.
|
|
*/
|
|
export function setupEncryption() {
|
|
console.log('[Encryption] Module loaded');
|
|
}
|