X3DH (Extended Triple Diffie-Hellman)


A TypeScript implementation of the Extended Triple Diffie-Hellman (X3DH) key agreement protocol, also known as the Signal protocol. This library uses libsodium for cryptographic operations and is designed for secure end-to-end encryption (E2EE) and key exchange.

Features

- X3DH key agreement protocol
- Uses libsodium for cryptography
- TypeScript support
- Suitable for E2EE and secure messaging

Installation

``sh
npm install @lookatfr3sn0/x3dh
`

Usage

`typescript
// ESM (recommended)
import { X3DH } from '@lookatfr3sn0/x3dh';

// CommonJS
const { X3DH } = require('@lookatfr3sn0/x3dh');
`

Important Note on Hash Algorithm

Due to limitations of the underlying sodium-plus library, the sha256 and sha512 options for the hash algorithm actually use BLAKE2b under the hood. This means that while the API allows you to select sha256 or sha512`, the cryptographic operations are performed using BLAKE2b with output lengths matching those of SHA-256 (32 bytes) or SHA-512 (64 bytes).

License

MIT © LookAtFr3sn0

Links

- GitHub Repository
- NPM Package