auth-check.ts

import { address as decodeAddress, concat, stringToBytes, verifySignature } from '@waves/ts-lib-crypto';
import { verifyCustomData } from '@waves/waves-transactions';


export function verifyAuthentication(signature: string, publicKey: string, address: string): string | null {
    const signedByAddress = decodeAddress({ publicKey });
    const messageBytes = stringToBytes(address);
    const authDataString = concat([255, 255, 255, 1], messageBytes);
    if (
        verifyCustomData({
            // KEEPERHUIPER
            version: 2,
            signature,
            publicKey,
            data,
        } as any)
    ) {
        return address;
    }
    return verifySignature(publicKey, authDataString, signature) ? address : null;
}