calculateSecret method
Generates the secret S given the server's credentials @param serverB The server's credentials @return Client's verification message for the server @throws Exception If server's credentials are invalid
Implementation
@override
BigInt? calculateSecret(BigInt serverB) {
B = SRP6Util.validatePublicValue(N, serverB);
u = SRP6Util.calculateU(digest, N, A, B);
S = calculateS();
return S;
}