Module sodiumoxide::crypto::secretbox

Secret-key authenticated encryption

Security model

The seal() function is designed to meet the standard notions of privacy and authenticity for a secret-key authenticated-encryption scheme using nonces. For formal definitions see, e.g., Bellare and Namprempre, “Authenticated encryption: relations among notions and analysis of the generic composition paradigm,” Lecture Notes in Computer Science 1976 (2000), 531–545, http://www-cse.ucsd.edu/~mihir/papers/oem.html.

Note that the length is not hidden. Note also that it is the caller’s responsibility to ensure the uniqueness of nonces—for example, by using nonce 1 for the first message, nonce 2 for the second message, etc. Nonces are long enough that randomly generated nonces have negligible risk of collision.

Selected primitive

seal() is crypto_secretbox_xsalsa20poly1305, a particular combination of Salsa20 and Poly1305 specified in Cryptography in NaCl.

This function is conjectured to meet the standard notions of privacy and authenticity.

Example

use sodiumoxide::crypto::secretbox;
let key = secretbox::gen_key();
let nonce = secretbox::gen_nonce();
let plaintext = b"some data";
let ciphertext = secretbox::seal(plaintext, &nonce, &key);
let their_plaintext = secretbox::open(&ciphertext, &nonce, &key).unwrap();
assert!(plaintext == &their_plaintext[..]);

Re-exports

pub use self::xsalsa20poly1305::*;

Modules

xsalsa20poly1305

crypto_secretbox_xsalsa20poly1305, a particular combination of Salsa20 and Poly1305 specified in Cryptography in NaCl.