TLSServerAutomaton in tls1.3 of Scapy v2.6.1 cannot save_ticket(TLS13NewSessionTicket)

Brief description

Using TLSServerAutomaton in tls1.3 of Scapy v2.6.1, after client access, TLS13NewSessionTicket cannot be saved to a file.

Scapy version

2.6.1

Python version

3.13

Operating system

windows11

Additional environment information

No response

How to reproduce

Start a tls server using the following code

    tls13_s = TLSServerAutomaton(
        **ssl_config,
        handle_session_ticket=True,
        session_ticket_file='./server_ticket.b'
    )
    tls13_s.run()

Check the following code.In some cases, TLS13NewSessionTicket may be added to "self.tls_session.post_handshake_messages", and is it necessary to check "self.tls_session.post_handshake_messages" when save_ticket?

class TLS13NewSessionTicket(_TLSHandshake):
    def tls_session_update(self, msg_str):
        """
        Covers both post_build- and post_dissection- context updates.
        """
        # RFC8446 sect 4.4.1
        # "Note, however, that subsequent post-handshake authentications do not
        # include each other, just the messages through the end of the main
        # handshake."
        if self.tls_session.post_handshake:
            self.tls_session.post_handshake_messages.append(msg_str)
        else:
            self.tls_session.handshake_messages.append(msg_str)
            self.tls_session.handshake_messages_parsed.append(self)
			
class TLSServerAutomaton(_TLSAutomaton):
    @ATMT.condition(ADDED_SERVERDATA)
    def should_send_ServerData(self):
        if self.session_ticket_file:
            save_ticket = False
            for p in self.buffer_out:
                if isinstance(p, TLS13):
                    # Check if there's a NewSessionTicket to send
                    save_ticket = all(map(lambda x: isinstance(x, TLS13NewSessionTicket),  # noqa: E501
                                          p.inner.msg))
                    if save_ticket:
                        break
        self.flush_records()
        if self.session_ticket_file and save_ticket:
            # Loop backward in message send to retrieve the parsed
            # NewSessionTicket. This message is not completely build before the
            # flush_records() call. Other way to build this message before ?
            for p in reversed(self.cur_session.handshake_messages_parsed):
                if isinstance(p, TLS13NewSessionTicket):
                    self.save_ticket(p)
                    break
        raise self.SENT_SERVERDATA()

Actual result

TLS13NewSessionTicket cannot be saved to a file

Expected result

TLS13NewSessionTicket can be saved to a file

Related resources

No response

Start by tracing TLSServerAutomaton.should_send_ServerData and TLS13NewSessionTicket.tls_session_update, focusing on where post_handshake_messages and handshake_messages_parsed are populated. Reproduce the TLSServerAutomaton configuration from the issue on Python 3.13, then verify that a TLS13NewSessionTicket is saved to session_ticket_file after client access.