Crate nostringer

Nostringer Ring Signatures (Rust)

A Rust implementation of Ring signatures (SAG, BLSAG) for Nostr.

This library provides functions to sign and verify messages using a Spontaneous Anonymous Group (SAG)-like or Back’s Linkable Spontaneous Anonymous Group (bLSAG) ring signature scheme over the secp256k1 curve.

Modules

• sag: Implements the original Spontaneous Anonymous Group (SAG) ring signature.
• blsag: Implements the Back’s Linkable Spontaneous Anonymous Group (bLSAG) ring signature.
• types: Defines common types like keys, signatures, and errors.
• utils: Provides utility functions for hashing, conversions, etc.
• wasm: Contains bindings for WebAssembly usage.
• keys: Contains key-related functions.
• serialization: Implements compact signature serialization.

Usage

use nostringer::{sign, verify, SignatureVariant, types::KeyPairHex, keys::generate_keypair_hex};

fn main() -> Result<(), nostringer::types::Error> {
    // 1. Setup: Generate keys for the ring members
    let keypair1 = generate_keypair_hex("xonly"); // Use "xonly", "compressed", or "uncompressed"
    let keypair2 = generate_keypair_hex("xonly");
    let keypair3 = generate_keypair_hex("xonly");

    let ring_pubkeys_hex = vec![
        keypair1.public_key_hex.clone(),
        keypair2.public_key_hex.clone(),
        keypair3.public_key_hex.clone(),
    ];

    // 2. Define the message to be signed
    let message = b"This is a secret message to the group.";

    // 3. Signer (keypair2) signs the message using the default SAG signature variant
    let signature = sign(
        message,
        &keypair2.private_key_hex,
        &ring_pubkeys_hex,
        SignatureVariant::Sag,
    )?;

    println!("Generated Compact Signature: {}", signature);

    // 4. Verification: Anyone can verify the signature against the ring
    let is_valid = verify(
        &signature,
        message,
        &ring_pubkeys_hex,
    )?;

    println!("Signature valid: {}", is_valid);
    assert!(is_valid);

    Ok(())
}

Re-exports

pub use types::Error;

pub use types::KeyPair;

pub use types::KeyPairHex;

pub use types::RingSignature;

pub use types::RingSignatureBinary;

pub use types::SignatureVariant;

pub use serialization::CompactSignature;

pub use serialization::SerializationError;

pub use types::hex_to_scalar;

pub use keys::generate_keypair_hex;

pub use keys::generate_keypairs;

pub use keys::get_public_keys;

Modules

blsag

keys

sag

serialization

types

utils

Functions

sign

Signs a message with a ring signature in compact format.

sign_compact_blsag

Creates a compact, serialized bLSAG ring signature (ringA... format).

sign_compact_sag

Creates a compact, serialized SAG ring signature (ringA... format).

verify

Verifies a compact ring signature.

verify_compact

Verifies a compact, serialized ring signature (ringA... format).