Module crypto_aead_xchacha20poly1305_ietf 

XChaCha20-Poly1305-IETF authenticated encryption

Implements libsodium’s crypto_aead_xchacha20poly1305_ietf_* functions. This construction authenticates optional additional data, appends the authentication tag in combined mode, and uses 192-bit public nonces.

Compatibility note

This module follows libsodium’s XChaCha20-Poly1305-IETF API and message size limit. The _ietf suffix refers to the RFC 8439 AEAD layout and Poly1305 input format; libsodium’s XChaCha implementation uses an extended-counter XChaCha20 stream so it can support larger individual messages than plain ChaCha20-Poly1305-IETF.

Classic API example

use dryoc::classic::crypto_aead_xchacha20poly1305_ietf::*;
use dryoc::constants::CRYPTO_AEAD_XCHACHA20POLY1305_IETF_ABYTES;
use dryoc::types::*;

let key = crypto_aead_xchacha20poly1305_ietf_keygen();
let nonce = Nonce::generate();
let message = b"hello";
let aad = b"metadata";

let mut ciphertext = vec![0u8; message.len() + CRYPTO_AEAD_XCHACHA20POLY1305_IETF_ABYTES];
crypto_aead_xchacha20poly1305_ietf_encrypt(&mut ciphertext, message, Some(aad), &nonce, &key)
    .expect("encrypt failed");

let mut decrypted = vec![0u8; message.len()];
crypto_aead_xchacha20poly1305_ietf_decrypt(
    &mut decrypted,
    &ciphertext,
    Some(aad),
    &nonce,
    &key,
)
.expect("decrypt failed");

assert_eq!(message, decrypted.as_slice());

Functions

crypto_aead_xchacha20poly1305_ietf_decrypt

Decrypts ciphertext with nonce, key, and optional associated data.

crypto_aead_xchacha20poly1305_ietf_decrypt_detached

Detached version of crypto_aead_xchacha20poly1305_ietf_decrypt.

crypto_aead_xchacha20poly1305_ietf_decrypt_detached_inplace

In-place detached variant of crypto_aead_xchacha20poly1305_ietf_decrypt_detached.

crypto_aead_xchacha20poly1305_ietf_decrypt_inplace

Decrypts data in place after verifying the appended authentication tag.

crypto_aead_xchacha20poly1305_ietf_encrypt

Encrypts message with nonce, key, and optional associated data.

crypto_aead_xchacha20poly1305_ietf_encrypt_detached

Detached version of crypto_aead_xchacha20poly1305_ietf_encrypt.

crypto_aead_xchacha20poly1305_ietf_encrypt_detached_inplace

In-place detached variant of crypto_aead_xchacha20poly1305_ietf_encrypt_detached.

crypto_aead_xchacha20poly1305_ietf_encrypt_inplace

Encrypts data in place and appends the authentication tag.

crypto_aead_xchacha20poly1305_ietf_keygen

Generates a random key using copy_randombytes.

crypto_aead_xchacha20poly1305_ietf_keygen_inplace

In-place variant of crypto_aead_xchacha20poly1305_ietf_keygen.

Type Aliases

Key

Secret key for XChaCha20-Poly1305-IETF AEAD.

Mac

Authentication tag for XChaCha20-Poly1305-IETF AEAD.

Nonce

Public nonce for XChaCha20-Poly1305-IETF AEAD.