nautilus_lighter/signing/schnorr/mod.rs
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15
16//! Schnorr signatures over the ECgFp5 curve, with Poseidon2 as the binding hash.
17//!
18//! - [`PrivateKey`] wraps a curve scalar; [`PublicKey`] wraps the canonical
19//! `Fp5` encoding `w = (sk * G).encode()`.
20//! - [`Signature`] is the `(s, e)` pair encoded as `s_le || e_le` over 80 bytes.
21//! - [`PrivateKey::sign`] produces a signature for a pre-hashed message under a
22//! caller-supplied per-signature nonce `k`. Production callers must draw `k`
23//! from a cryptographic RNG; the explicit-nonce form mirrors the Go
24//! reference's `SchnorrSignHashedMessage2`, which fixture tests pin against.
25//! - [`PublicKey::verify`] decodes the public-key encoding, recomputes
26//! `s*G + e*pk`, and checks the recovered challenge against the signature.
27//!
28//! Hash-to-quintic of the message is the caller's responsibility, matching the
29//! upstream API. Use [`super::hash::hash_to_quintic_extension`] over the
30//! message field elements.
31
32mod key;
33mod sig;
34
35pub use key::{PrivateKey, PublicKey};
36pub use sig::{SIG_BYTES, Signature};