Struct Encryptor 

pub struct Encryptor { /* private fields */ }

An encryptor utilizing XChaCha20Poly1305 authenticated encryption with a Kyber shared secret

This struct provides an interface for encrypting and decrypting data using a post-quantum shared secret established via ML-KEM (formerly Kyber). It uses XChaCha20Poly1305 for authenticated encryption with associated data (AEAD).

Implementations

impl Encryptor

pub fn new(shared_secret: SharedSecret) -> Self

Creates a new encryptor with the given shared secret

Arguments

• shared_secret - The ML-KEM shared secret to use for encryption/decryption

Returns

A new Encryptor instance initialized with the provided shared secret

pub fn encrypt( &self, plaintext: &[u8], nonce: &[u8; 24], ) -> Result<Vec<u8>, CryptoError>

Encrypts plaintext using XChaCha20Poly1305 with the stored shared secret

Arguments

• plaintext - The data to encrypt
• nonce - A 24-byte nonce (must be unique for each encryption with the same key)

Returns

• Result<Vec<u8>, CryptoError>: The encrypted ciphertext or an error

Security Notes

• The nonce must never be reused with the same key
• The ciphertext includes an authentication tag to verify integrity

pub fn decrypt( &self, ciphertext: &[u8], nonce: &[u8; 24], ) -> Result<Vec<u8>, CryptoError>

Decrypts ciphertext using XChaCha20Poly1305 with the stored shared secret

Arguments

• ciphertext - The encrypted data to decrypt
• nonce - The 24-byte nonce used during encryption

Returns

• Result<Vec<u8>, CryptoError>: The decrypted plaintext or an error

Security Notes

• This function will return an error if the ciphertext has been tampered with
• The same nonce used for encryption must be provided for decryption