Logon Password Authentication

While Accepting an incoming FIX connection, additional authentication checks may be required. The typical checks are Logon username/password and source IP address.

The required authentication logic could be added to the OnixS::FIX::ISessionListener::onInboundSessionMsg(..) method. If the authentication fails and the FIX connection needs to be rejected (closed) then the std::runtime_error exception (or the derived one) should be thrown.

For example:

bool doAuthentication(const Message& , std::string& )
{
    // Perform some authentication.
    return true;
}
 
class SessionListener : public ISessionListener
{
public:
 
    void onInboundSessionMsg(Message& message, Session*) override
    {
        if (message.type() == OnixS::FIX::FIX40::Values::MsgType::Logon)
        {
            std::string reason;
 
            // Do user authentication here
            if (!doAuthentication(message, reason))
            {
                throw std::runtime_error(reason);
            }
        }
    }
};

If the std::runtime_error exception is thrown and OnixS::FIX::EngineSettings::sendLogoutOnException(..) or OnixS::FIX::Session::sendLogoutOnException(..) is set to true then the Logout FIX message will be sent before closing the FIX connection. Otherwise, the connection will be closed immediately.