Struct Ed25519Signer 

pub struct Ed25519Signer { /* private fields */ }

An Ed25519 (-19) signer. Ed25519 is deterministic, so the shared vectors compare its output byte for byte.

It signs the to-be-signed structure in pieces, like the HMAC and ESP256 signers, without the envelope building it in one buffer (maintainer decision on cratestack#1005, 2026-09-25). PureEdDSA (RFC 8032) is not a pre-hash scheme: it hashes the message twice, once for the nonce r and once for the challenge k. ed25519-dalek’s MultipartSigner runs both passes over the same slices, the computation its hazmat module exposes as raw_sign_byupdate, but with the secret expanded the standard way inside the crate. Reaching it through the safe trait needs no hazmat feature, and so no code here derives an ExpandedSecretKey itself, which is the misuse that module warns can leak the key. The result is byte for byte what signing the concatenation gives (tests/ed25519_streaming.rs checks every vector and a range of sizes).

Implementations

impl Ed25519Signer

pub fn from_seed(seed: &[u8; 32]) -> Ed25519Signer

The signer for the RFC 8032 secret key seed (32 random bytes). The key is expanded here, and wiped when the signer is dropped.

pub fn verify_key(&self) -> CoseVerifyKey

The matching verification key, for a resolver.

Trait Implementations

impl Clone for Ed25519Signer

fn clone(&self) -> Ed25519Signer

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl CoseSigner for Ed25519Signer

fn sign_chunks( &self, to_be_signed: &[&[u8]], ) -> Option<Result<Vec<u8>, CratestackError>>

Both PureEdDSA passes over the pieces (see the type’s docs).

fn alg(&self) -> CoseAlg

The algorithm every signature from this signer uses.

fn kid(&self) -> &[u8]

The key’s kid: the first 8 bytes of its RFC 9679 thumbprint (§3).

fn sign<'life0, 'life1, 'async_trait>( &'life0 self, to_be_signed: &'life1 [u8], ) -> Pin<Box<dyn Future<Output = Result<Vec<u8>, CratestackError>> + Send + 'async_trait>>

where 'life0: 'async_trait, 'life1: 'async_trait, Ed25519Signer: 'async_trait,

Sign (or MAC) to_be_signed. For HMAC 256/64 this returns the truncated 8-byte tag. An error is a backend failure (a 500).

impl Debug for Ed25519Signer

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

Formats the value using the given formatter.