Struct Blake3Mac 

pub struct Blake3Mac { /* private fields */ }

Available on (crate features mac-hmac or mac-blake3) and crate feature mac-blake3 only.

Streaming BLAKE3 keyed-mode MAC for inputs that don’t fit in memory.

Construct with Blake3Mac::new, absorb data with update, and finalise with finalize (returns the 32-byte tag) or verify (constant-time compare against an expected tag).

Example

use crypt_io::mac::Blake3Mac;

let key = [0x42u8; 32];
let mut m = Blake3Mac::new(&key);
m.update(b"first chunk ");
m.update(b"second chunk");
let tag = m.finalize();
assert_eq!(tag.len(), 32);

Implementations

impl Blake3Mac

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

Construct a fresh keyed MAC.

Unlike HMAC this is infallible — BLAKE3’s keyed mode takes a type-checked 32-byte key, so there is no runtime length-check to fail.

pub fn update(&mut self, data: &[u8]) -> &mut Self

Absorb data into the running MAC. Returns &mut Self so calls can chain.

pub fn finalize(self) -> [u8; 32]

Finalise the MAC and return the 32-byte tag. Consumes the hasher.

pub fn verify(self, expected_tag: &[u8]) -> bool

Finalise and verify against expected_tag in constant time. Returns true iff the computed tag matches expected_tag (and expected_tag is the correct length). Consumes the hasher.

Trait Implementations

impl Clone for Blake3Mac

fn clone(&self) -> Blake3Mac

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Blake3Mac

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.