End-to-End Encryption (E2EE)

In Cypher, messages are encrypted on your device using the recipient’s public key, and can only be decrypted by the recipient’s corresponding private key. This ensures that only you and your conversation partners can view the contents of your messages.

Key Points

• Public and private key pairs are generated securely on your device.
• Your private key never leaves your device, ensuring confidentiality.
• Even Cypher’s own servers can’t read your messages.

Basic RSA Encryption Example

Below is a simple Node.js snippet illustrating RSA key generation, encryption, and decryption. You can adapt this logic for various programming languages and environments.

import crypto from 'crypto';

// Generate RSA key pair
const { publicKey, privateKey } = crypto.generateKeyPairSync('rsa', {
  modulusLength: 2048,
  publicKeyEncoding: {
    type: 'pkcs1',
    format: 'pem',
  },
  privateKeyEncoding: {
    type: 'pkcs1',
    format: 'pem',
  },
});

// Sample message
const message = 'Hello from Cypher!';

// Encrypt with public key
const encryptedData = crypto.publicEncrypt(publicKey, Buffer.from(message));

// Decrypt with private key
const decryptedData = crypto.privateDecrypt(privateKey, encryptedData);

console.log('Encrypted:', encryptedData.toString('base64'));
console.log('Decrypted:', decryptedData.toString());

How Cypher Uses It

In a real Cypher conversation, the app automatically handles key generation, exchange, and message encryption under the hood. You simply chat normally, and the encryption ensures privacy at all times.