[gnutls-help] DTLS and gnutls_bye

[Nikos Mavrogiannopoulos]

On Tue, 2017-02-14 at 18:07 -0800, Sean Greenslade wrote:

> > > Specifically, the behavior I'm seeing is this. gnutls_bye does
> > > send the
> > > close alert message over the wire, however the receiving end does
> > > not
> > > raise an alert error when checking for received packets.
> > 
> > What does the other side receive?
> 
> When the close alert packet gets sent from the client to the server,
> I
> can see it on the wire (encrypted, of course). The server has a
> multiplexer function that handles multiple clients simultaneously,
> and
> it sees a packet from the client and calls gnutls_record_recv() to
> process it. gnutls_record_recv() returns zero, apparently ignoring
> the
> alert flag while consuming the packet.

Returning zero is the expected behavior (EOF) from gnutls_record_recv,
when the closure alert is received.

regards,
Nikos