The idea is to remove the limitation of only two protocols ("master" and
"app") in the flow classifcation.
This is quite handy expecially for STUN flows and, in general, for any
flows where there is some kind of transitionf from a cleartext protocol
to TLS: HTTP_PROXY -> TLS/Youtube; SMTP -> SMTPS (via STARTTLS msg).
In the vast majority of the cases, the protocol stack is simply
Master/Application.
Examples of real stacks (from the unit tests) different from the standard
"master/app":
* "STUN.WhatsAppCall.SRTP": a WA call
* "STUN.DTLS.GoogleCall": a Meet call
* "Telegram.STUN.DTLS.TelegramVoip": a Telegram call
* "SMTP.SMTPS.Google": a SMTP connection to Google server started in
cleartext and updated to TLS
* "HTTP.Google.ntop": a HTTP connection to a Google domain (match via
"Host" header) and to a ntop server (match via "Server" header)
The logic to create the stack is still a bit coarse: we have a decade of
code try to push everything in only ywo protocols... Therefore, the
content of the stack is still **highly experimental** and might change
in the next future; do you have any suggestions?
It is quite likely that the legacy fields "master_protocol" and
"app_protocol" will be there for a long time.
Add some helper to use the stack:
```
ndpi_stack_get_upper_proto();
ndpi_stack_get_lower_proto();
bool ndpi_stack_contains(struct ndpi_proto_stack *s, u_int16_t proto_id);
bool ndpi_stack_is_tls_like(struct ndpi_proto_stack *s);
bool ndpi_stack_is_http_like(struct ndpi_proto_stack *s);
```
Be sure new stack logic is compatible with legacy code:
```
assert(ndpi_stack_get_upper_proto(&flow->detected_protocol.protocol_stack) ==
ndpi_get_upper_proto(flow->detected_protocol));
assert(ndpi_stack_get_lower_proto(&flow->detected_protocol.protocol_stack) ==
ndpi_get_lower_proto(flow->detected_protocol));
```
This function is always called once for every flow, as last code
processing the flow itself.
As a first usage example, check here if the flow is unidirectional
(instead of checking it at every packets)
This cache was added in b6b4967aa, when there was no real Zoom support.
With 63f349319, a proper identification of multimedia stream has been
added, making this cache quite useless: any improvements on Zoom
classification should be properly done in Zoom dissector.
Tested for some months with a few 10Gbits links of residential traffic: the
cache pretty much never returned a valid hit.
The goal if to correlate the right request-response pair, exporting
metadata from only one transaction (for example, the right url & return
state pair)
As a nice side effect, the code should be much cleaner, but that is a
matter of taste.
Two differences respect to the previous code:
* as it happens in the CI, if in the flow there are only one response
(before) and one request (after), only the metadata of the response are
saved/exported
* for performance reasons, we don't call `ndpi_parse_packet_line_info()`
anymore for ALL packets triggering the HTTP dissector, but only for the
packets that we already know belong to an HTTP flow. This is the reason
for the changes in RTSP/SOAP/... code
Extend internal unit tests to handle multiple configurations.
As some examples, add tests about:
* disabling some protocols
* disabling Ookla aggressiveness
Every configurations data is stored in a dedicated directory under
`tests\cfgs`
2023-04-06 11:30:36 +02:00
Renamed from tests/result/mpeg-dash.pcap.out (Browse further)
