Crate deevee

This crate provides an implementation of designated verifier signatures. This is like a normal signature scheme, except that the signer also designates a verifier for their signature.

Only this verifier can validate the signature. Furthermore, this verifier can’t convince anyone else of the validity of the signature, because they can forge signatures which designate them as the verifier.

Here’s an example which illustrates all of this functionality:

use deevee::*;
use rand_core::OsRng;

let (privA, pubA) = generate_keypair(&mut OsRng);
let (privB, pubB) = generate_keypair(&mut OsRng);
let (privC, pubC) = generate_keypair(&mut OsRng);

let sig = privA.sign(&mut OsRng, &pubB, b"I like cats");
// The signature verifies, because the designee matches
assert!(privB.verify(&pubA, b"I like cats", &sig));
// If we change the message, verification fails
assert!(!privB.verify(&pubA, b"I don't like cats", &sig));
// The signer won't verify with a different signer either
assert!(!privB.verify(&pubC, b"I like cats", &sig));
// The wrong verifier can't validate the signature either
assert!(!privC.verify(&pubA, b"I like cats", &sig));
// Finally, the verifier can forge a valid signature for themselves
let forged = privB.forge(&mut OsRng, &pubA, b"I don't like cats");
assert!(privB.verify(&pubA, b"I don't like cats", &forged));

Structs

PrivateKey

Represents a private key.

PublicKey

PublicKey represents an identity.

Signature

Represents a signature designated for a specific verifier.

Functions

generate_keypair

Generate a new private key, along with its associated public key.