libsignal-dezire

A Rust implementation of the VXEdDSA signing scheme by Signal, designed for high-performance and secure cryptographic operations. This library also provides C-compatible FFI bindings for integration with other languages.

Features

• VXEdDSA Signing & Verification: Secure deterministic signatures with verifiable randomness.
• X25519 & Ed25519 Interop: Utilities to convert between Montgomery and Edwards curve points.
• FFI Support: extern "C" functions for key generation and secret management, suitable for calling from C/C++, iOS (Swift), and Android (Kotlin/JNI).

Installation

Add this to your Cargo.toml:

[dependencies]
libsignal-dezire = "0.1.11"

Usage

Rust Example

use libsignal_dezire::vxeddsa::{vxeddsa_sign, vxeddsa_verify};
use libsignal_dezire::utils::calculate_key_pair;
use rand_core::{OsRng, RngCore};

fn main() {
    // 1. Generate a random private key seed
    let mut seed_k = [0u8; 32];
    OsRng.fill_bytes(&mut seed_k);

    // 2. Define a message to sign
    let message = b"Hello, VXEdDSA!";
    let mut msg_bytes = [0u8; 32];
    // In a real app, hash the message to 32 bytes
    msg_bytes[0..message.len()].copy_from_slice(message);

    // 3. Sign
    let (signature, vrf_output) = vxeddsa_sign(seed_k, &msg_bytes);

    // 4. Verify
    // Derive public key for verification
    let (_, public_point) = calculate_key_pair(seed_k);
    let public_u = public_point.to_montgomery().to_bytes();

    let verified_vrf = vxeddsa_verify(public_u, &msg_bytes, &signature);

    assert_eq!(verified_vrf.unwrap(), vrf_output);
    println!("Signature verified successfully!");
}

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

This project is licensed under the AGPL-v3 License - see the LICENSE file for details.