Should nonce not be changed for every segment?

[Hoeze]

Hi, I try to understand how the Crypt4GH standard works and therefore checked this library as a reference.

Checking the source code, I see that nonce_bytes gets initialized once:

crypt4gh-rust/src/lib.rs

Lines 153 to 155 in 2d41a17

	let mut rnd = rand_chacha::ChaCha20Rng::from_entropy();
	let mut nonce_bytes = [0u8; 12];
	rnd.fill(&mut nonce_bytes);

However, it seems like nonce_bytes then gets used without ever changing it during looping over the data stream:

crypt4gh-rust/src/lib.rs

Line 189 in 2d41a17

let nonce = Nonce::from_slice(&nonce_bytes);

Is this correct? Should the nonce not be changed every time, e.g. by incrementing it by 1, when encrypting a new segment?

[tedil]

Agree, should either be a new random nonce for every segment, or increment some counter.