Struct Hbss 

pub struct Hbss {
    pub scheme: Scheme,
    pub w: u32,
    pub batch: u32,
}

The hash-based one-time signature scheme (HBSS) and its batching.

DSig signs with W-OTS+: a message digest is cut into base-w digits, one hash chain per digit plus a few checksum chains. Each chain is hashed w − 1 times at key generation. Larger w means fewer, longer chains: shorter signatures, more hashing. The built hardware is w = 4, 128-bit digests (64 digits + 4 checksum digits = 68 chains of 3 steps) and K = 128 keys per batch; every other combination is a model.

Fields

scheme: Scheme

The scheme; only W-OTS+ has hardware and a cost model.

w: u32

Winternitz parameter: digits are base w, chains have w − 1 steps.

batch: u32

Keys per batch, certified by one Ed25519 signature (K).

Implementations

impl Hbss

pub const DIGEST_BITS: u32 = 128

Bits of the message digest that the digits encode.

pub fn built(self) -> bool

The scheme the hardware implements.

pub fn message_digits(self) -> u32

Message digits: 128 / log2 w.

pub fn checksum_digits(self) -> u32

Checksum digits: the fewest base-w digits that can hold the largest checksum, message_digits × (w − 1).

pub fn chains(self) -> u32

Hash chains per key (68 for the built scheme).

pub fn steps_per_key(self) -> f64

Chain steps to make one key: every chain hashed w − 1 times (204).

pub fn blake3_per_key(self) -> f64

BLAKE3 compressions to make one key: 3 for seeds and nonces, the XOF that makes 18 secret bytes per chain, the commitment over 18 endpoint bytes per chain (plus a 16-byte prefix), and 2 for the Merkle leaf.

pub fn key_period(self) -> f64

Cycles one slice needs per key: its three chain lanes do three steps per clock, its BLAKE3 lane one compression per clock, and the chain engine takes one chain per clock. The busiest of the three sets the period. For the built scheme every term but BLAKE3 is 68.

pub fn merkle_height(self) -> u32

Merkle levels from a key to its batch root: log2 K.

pub fn signature_bytes(self) -> u32

Signature bytes: one 18-byte node per chain, one 32-byte sibling per Merkle level, and 194 bytes of fixed fields (nonces, indices, root, certificate). 1,642 for the built scheme.

pub fn verify_steps(self) -> f64

Expected chain steps to finish one verification. The built scheme uses VERIFY_CHAIN_STEPS; for other w each chain needs on average half its length.

pub fn verify_blake3(self) -> f64

BLAKE3 compressions per verification: the endpoint commitment (its blocks plus one parent per extra 1 KiB chunk), the message digest and one per Merkle level. 21 + 1 + 7 = 29 for the built scheme, as the hardware counts (native simulation: 29.00 per record).

pub fn label(self) -> String

A short label, e.g. W-OTS+ w=4, 68 chains, K=128, 1642 B.

Trait Implementations

impl Clone for Hbss

fn clone(&self) -> Hbss

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Hbss

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

Formats the value using the given formatter.

impl Default for Hbss

fn default() -> Self

Returns the “default value” for a type.

impl PartialEq for Hbss

fn eq(&self, other: &Hbss) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for Hbss

impl Eq for Hbss

impl StructuralPartialEq for Hbss