Struct Kmac256 

pub struct Kmac256 { /* private fields */ }

SP 800-185 KMAC256, offering 256-bit security.

Implementations

impl Kmac256

pub fn new(key: &[u8], custom: &[u8]) -> Self

Start a KMAC with key and a customization string.

Pass an empty custom when the key has only one use.

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

Absorb more of the message.

pub fn finalize(self, out: &mut [u8]) -> Result<()>

Produce a tag of exactly out.len() bytes.

The length is bound into the computation, so tags of different lengths over the same input are unrelated. Refuses with ModuleErrorState once the module has failed.

pub fn finalize_xof(self, out: &mut [u8]) -> Result<()>

Produce an arbitrary-length stream instead of a fixed tag.

Encodes a length of zero, per SP 800-185 section 4.3.1. Refuses with ModuleErrorState once the module has failed.

pub fn mac(key: &[u8], custom: &[u8], data: &[u8], out: &mut [u8]) -> Result<()>

One-shot fixed-length tag.

pub fn mac_xof( key: &[u8], custom: &[u8], data: &[u8], out: &mut [u8], ) -> Result<()>

One-shot XOF mode.

pub fn verify(key: &[u8], custom: &[u8], data: &[u8], tag: &[u8]) -> Result<()>

Verify a tag in constant time.

Compare with this rather than ==. An early-exit comparison leaks how many leading bytes matched, which is enough to recover a valid tag one byte at a time.

Trait Implementations

impl Algorithm for Kmac256

const ID: &'static str = "kmac256"

Stable ontology identifier for this algorithm.

const NAME: &'static str = "KMAC256"

Human-facing display name (for example "SHA-256").

impl Clone for Kmac256

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl SelfTest for Kmac256

fn self_test() -> Result<()>

Provenance

No pinned vector. The unit tests check KMAC against an independent construction from SP 800-185’s own definition — stronger evidence than a value this code produced — and cSHAKE beneath it is checked against a Keccak written from FIPS 202. docs/FIPS.md records that. What this adds at startup is that the code still computes what it computed when those tests last ran, and that its structural properties hold.