Encryption Details

Parameters

Why Argon2id?

• Memory-hard: Requires significant RAM, making GPU/ASIC attacks economically infeasible
• Hybrid approach: Argon2id combines Argon2i (data-independent) and Argon2d (data-dependent) for side-channel resistance and brute-force defense
• Industry standard: Recommended by OWASP, used by major password managers
• Configurable: Parameters can be tuned for security vs. performance trade-offs

Implementation

We use the argon2-browser library, a WebAssembly implementation of Argon2 that runs efficiently in modern browsers:

import { hash } from 'argon2-browser';

const result = await hash({
  pass: masterPassword,
  salt: salt,
  time: 3,           // iterations
  mem: 65536,        // 64 MB
  hashLen: 32,       // 256 bits
  parallelism: 1,
  type: argon2.Type.Argon2id
});

const encryptionKey = result.hash;

Specifications

Why AES-256-GCM?

• Military-grade: Used by US government for TOP SECRET information (NSA Suite B)
• Authenticated encryption: GCM mode provides both encryption and integrity verification
• Performance: Hardware-accelerated on modern CPUs via AES-NI instructions
• Proven security: No known practical attacks against AES-256
• Key size: 256-bit keys provide protection against quantum computing attacks (Grover's algorithm)

Implementation

We use the browser's native Web Crypto API for AES-GCM operations:

// Encryption
const iv = crypto.getRandomValues(new Uint8Array(12));
const encrypted = await crypto.subtle.encrypt(
  {
    name: 'AES-GCM',
    iv: iv,
    tagLength: 128
  },
  encryptionKey,
  vaultData
);

// Decryption
const decrypted = await crypto.subtle.decrypt(
  {
    name: 'AES-GCM',
    iv: iv,
    tagLength: 128
  },
  encryptionKey,
  ciphertext
);