Trusted Dealer Key Generation

The diagram below shows the trusted dealer key generation process. Dashed lines represent data being sent through an authenticated and confidential communication channel.

To generate the key shares, the dealer calls generate_with_dealer(). It returns a BTreeMap mapping the (automatically generated) Identifiers to their respective SecretShares, and a PublicKeyPackage which contains the VerifyingShare for each participant and the group public key (VerifyingKey).

use frost_ristretto255 as frost;
use rand::thread_rng;
use std::collections::BTreeMap;

let mut rng = thread_rng();
let max_signers = 5;
let min_signers = 3;
let (shares, pubkey_package) = frost::keys::generate_with_dealer(
    max_signers,
    min_signers,
    frost::keys::IdentifierList::Default,
    &mut rng,
)?;

Each SecretShare must then be sent via an authenticated and confidential channel for each participant, who must verify the package to obtain a KeyPackage which contains their signing share, verifying share and group verifying key. This is done with KeyPackage::try_from():

    let key_package = frost::keys::KeyPackage::try_from(secret_share)?;