chacha20poly1305

Chacha20Poly1305 Authenticated Encryption with Additional Data (AEAD) module for V Language

This module provides authenticated encryption with additional data (AEAD) algorithm in V Language. Its backed by experimental x.crypto.chacha20 symmetric key stream cipher encryption module and x.crypto.poly1305 message authentication code (MAC) module.

[!Warning] This is an absolutely experimental module, which is subject to change. Please use it carefully, thoroughly and wisely.

Supported features

The implemented features at the time of writing (2025/10/08) are:

• The standard ChaCha20 and Poly1305 construct for IETF Protocols defined in RFC 8439
• ChaCha20 Poly1305 AEAD construct with 8-bytes nonce.
• Support for eXtended ChaCha20 Poly1305 AEAD construct with 24 bytes nonce.
• Support for nonce-misuse resistent and key-commiting AEAD through ChaCha20-Poly1305-PSIV construction defined in the A Robust Variant of ChaCha20-Poly1305 paper.

Examples

import encoding.hex
import x.crypto.chacha20poly1305

fn main() {
    // plaintext message to be encrypted and authenticated
    message := "Ladies and Gentlemen of the class of '99: If I could offer you only one 
    tip for the future, sunscreen would be it.".bytes()

    // sets your secure random key
    key := hex.decode('808182838485868788898a8b8c8d8e8f909192939495969798999a9b9c9d9e9f')!
    // give yours nonce
    nonce := hex.decode('070000004041424344454647')!
    // yours additional data
    aad := hex.decode('50515253c0c1c2c3c4c5c6c7')!

    // lets doing authenticated encryption
    ciphertext := chacha20poly1305.encrypt(message, key, nonce, aad)!

    // lets perform decryption back
    plaintext := chacha20poly1305.decrypt(ciphertext, key, nonce, aad)!

    assert plaintext == message
}