Struct Encryptor 

pub struct Encryptor { /* private fields */ }

An encryptor utilizing XChaCha20Poly1305 authenticated encryption

This struct provides an interface for encrypting and decrypting data using a 32-byte symmetric key. It uses XChaCha20Poly1305 for authenticated encryption with associated data (AEAD). The key is wiped from memory on drop.

Derive the key with a KDF (as MessageSession does) rather than using a raw KEM shared secret, and never let two parties encrypt under the same key.

Implementations

impl Encryptor

pub fn new(key: &[u8; 32]) -> Self

Creates a new encryptor with the given key

Arguments

• key - The 32-byte key to use for encryption/decryption

Returns

A new Encryptor instance initialized with the provided key

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

Encrypts plaintext using XChaCha20Poly1305 with the stored key

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 key

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