antelope-webauthn/create_wa_signature.js

A WebAuthn.io crypto utility for generating signatures, creating public keys, and verifying them, designed for Antelope-based blockchains such as Vaulta, WAX, and other related platforms. This package provides convenient tools to handle key pair generatio

import assertBrowserCompatibility from "./_utils/browser-compatability";
import antelopeWebAuthnSignature from "./_utils/webauthn_signature.js";
export default async function createWebAuthnSignature(device_keys, hash) {
    assertBrowserCompatibility();
    const challenge = typeof hash == "string"
        ? (() => {
            const matches = hash.match(/[a-fA-F0-9]{2}/gmu);
            if (matches)
                return Uint8Array.from(matches.map((x) => Number(`0x${x}`)));
            // Handle the case where match returns null (no valid hex found)
            else
                throw new Error("Invalid hash string format");
        })()
        : hash;
    const allowCredentials = device_keys.map((key) => ({
        id: Uint8Array.from(window
            .atob(key.credential_id.replace(/-/gmu, "+").replace(/_/gmu, "/"))
            .split("")
            .map((i) => i.charCodeAt(0))),
        type: "public-key",
        alg: -7,
    }));
    const assertation = (await window.navigator.credentials.get({
        publicKey: {
            allowCredentials,
            challenge,
            timeout: 6e4,
            userVerification: "required",
        },
    }));
    const response = assertation.response;
    const device_key = device_keys.find((x) => x.credential_id == assertation.id);
    if (!device_key?.public_key)
        throw new Error("We were unable to produce a valid signature with the device keys you provided.");
    const antelope_signature = antelopeWebAuthnSignature(response, device_key.public_key);
    return antelope_signature;
}