Struct Ed25519Key 

pub struct Ed25519Key { /* private fields */ }

A signing key with its public key already derived.

Why this exists

RFC 8032 signing needs the public key: it goes into the hash that produces k. Ed25519::sign takes only the 32-byte seed, so it has to derive the public key on every call – a second basepoint multiplication, and with the table in place that is most of what a signature now costs.

A key that is used more than once should derive it once. That is what a TLS server does with a certificate key, and what dalek’s SigningKey does, which is why comparing Ed25519::sign against it was comparing two different amounts of work.

The trait method still exists and still takes a seed. This changes nothing for a caller signing once; it halves the cost for a caller signing twice.

Implementations

impl Ed25519Key

pub fn from_seed(seed: &[u8]) -> Result<Self>

Expand a 32-byte seed and derive its public key.

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

The public key, already derived.

pub fn sign(&self, message: &[u8], signature: &mut [u8]) -> Result<()>

Sign message, performing one basepoint multiplication rather than two.

Trait Implementations

impl Drop for Ed25519Key

fn drop(&mut self)

Executes the destructor for this type.

fn pin_drop(self: Pin<&mut Self>)

🔬This is a nightly-only experimental API. (pin_ergonomics)

Execute the destructor for this type, but different to Drop::drop, it requires self to be pinned.