Module schnorr 

Schnorr signatures over the ECgFp5 curve, with Poseidon2 as the binding hash.

• PrivateKey wraps a curve scalar; PublicKey wraps the canonical Fp5 encoding w = (sk * G).encode().
• Signature is the (s, e) pair encoded as s_le || e_le over 80 bytes.
• PrivateKey::sign produces a signature for a pre-hashed message under a caller-supplied per-signature nonce k. Production callers must draw k from a cryptographic RNG; the explicit-nonce form mirrors the Go reference’s SchnorrSignHashedMessage2, which fixture tests pin against.
• PublicKey::verify decodes the public-key encoding, recomputes s*G + e*pk, and checks the recovered challenge against the signature.

Hash-to-quintic of the message is the caller’s responsibility, matching the upstream API. Use super::hash::hash_to_quintic_extension over the message field elements.

Structs

PrivateKey

A Schnorr private key over the ECgFp5 scalar field.

PublicKey

A Schnorr public key over the ECgFp5 curve, stored as the canonical Fp5 encoding w = (sk * G).encode().

Signature

Schnorr signature over the ECgFp5 curve.

Constants

SIG_BYTES

Canonical wire length of a Signature: 40 bytes for s, 40 for e.