Module sodiumoxide::crypto::aead

Authenticated Encryption with Additional Data This operation:

• Encrypts a message with a key and a nonce to keep it confidential
• Computes an authentication tag. This tag is used to make sure that the message, as well as optional, non-confidential (non-encrypted) data, haven't been tampered with.

Selected primitive

seal(), seal_detached(), open() and open_detached() are currently an implementation of chacha20poly1305_ietf, i.e. the IETF construction defined in https://tools.ietf.org/html/rfc7539.

Example (combined mode)

use sodiumoxide::crypto::aead;

let k = aead::gen_key();
let n = aead::gen_nonce();
let m = b"Some plaintext";
let ad = b"Some additional data";

let c = aead::seal(m, Some(ad), &n, &k);
let m2 = aead::open(&c, Some(ad), &n, &k).unwrap();

assert_eq!(&m[..], &m2[..]);

Example (detached mode)

use sodiumoxide::crypto::aead;

let k = aead::gen_key();
let n = aead::gen_nonce();
let mut m = [0x41, 0x42, 0x43, 0x44];
let m2 = m.clone();
let ad = b"Some additional data";

let t = aead::seal_detached(&mut m, Some(ad), &n, &k);
aead::open_detached(&mut m, Some(ad), &t, &n, &k).unwrap();

assert_eq!(m, m2);

Re-exports

pub use self::xchacha20poly1305_ietf::*;

Modules

chacha20poly1305	The original ChaCha20-Poly1305 construction can safely encrypt a pratically unlimited number of messages with the same key, without any practical limit to the size of a message (up to ~ 2^64 bytes).
chacha20poly1305_ietf	The IETF variant of the ChaCha20-Poly1305 construction can safely encrypt a practically unlimited number of messages, but individual messages cannot exceed 64*(2^32)-64 bytes (approximatively 256 GB).
xchacha20poly1305_ietf	The XChaCha20-Poly1305 construction can safely encrypt a practically unlimited number of messages with the same key, without any practical limit to the size of the message (up to ~ 2^64 bytes).