Basically:
* "classification by-ip" (i.e. `flow->guessed_protocol_id_by_ip` is
NEVER returned in the protocol stack (i.e.
`flow->detected_protocol_stack[]`);
* if the application is interested into such information, it can access
`ndpi_protocol->protocol_by_ip` itself.
There are mainly 4 points in the code that set the "classification
by-ip" in the protocol stack: the generic `ndpi_set_detected_protocol()`/
`ndpi_detection_giveup()` functions and the HTTP/STUN dissectors.
In the unit tests output, a print about `ndpi_protocol->protocol_by_ip`
has been added for each flow: the huge diff of this commit is mainly due
to that.
Strictly speaking, this change is NOT an API/ABI breakage, but there are
important differences in the classification results. For examples:
* TLS flows without the initial handshake (or without a matching
SNI/certificate) are simply classified as `TLS`;
* similar for HTTP or QUIC flows;
* DNS flows without a matching request domain are simply classified as
`DNS`; we don't have `DNS/Google` anymore just because the server is
8.8.8.8 (that was an outrageous behaviour...);
* flows previusoly classified only "by-ip" are now classified as
`NDPI_PROTOCOL_UNKNOWN`.
See #1425 for other examples of why adding the "classification by-ip" in
the protocol stack is a bad idea.
Please, note that IPV6 is not supported :( (long standing issue in nDPI) i.e.
`ndpi_protocol->protocol_by_ip` wil be always `NDPI_PROTOCOL_UNKNOWN` for
IPv6 flows.
Define `NDPI_CONFIDENCE_MATCH_BY_IP` has been removed.
Close#1687
Add (basic) internal stats to the main data structures used by the
library; they might be usefull to check how effective these structures
are.
Add an option to `ndpiReader` to dump them; enabled by default in the
unit tests.
This new option enables/disables dumping of "num dissectors calls"
values, too (see b4cb14ec).
Since e6b332aa, we have proper support for detecting client/server
direction. So Tinc dissector is now able to properly initialize the
cache entry only when needed and not anymore at the SYN time; initializing
that entry for **every** SYN packets was a complete waste of resources.
Since 4896dabb, the various `struct ndpi_call_function_struct`
structures are not more separate objects and therefore comparing them
using only their pointers is bogus: this bug was triggered by this
change because `ndpi_str->callback_buffer_size_tcp_no_payload` is now 0.
We should have two protocols in classification results only when the
"master" protocol allows some sub-protocols.
Classifications like `AmazonAWS`, `TLS/AmazonAWS`, `DNS/AmazonAWS` are
fine. However classifications like `NTP/Apple`, `BitTorrent/Azure`,
`DNScrypt.AmazonAWS` or `NestLogSink.Google` are misleading.
For example, `ndpiReader`shows `BitTorrent/Azure` flows under `Azure`
statistics; that seems to be wrong or, at least, very misleading.
This is quite important since we have lots of addresses from CDN
operators.
The only drawback of this solution is that right now ICMP traffic is
classified simply as `ICMP`; if we are really interested in ICMP stuff
we can restore the old behaviour later.
Add detection of AccuWeather site/app and Google Classroom.
Improve detection of Azure, Zattoo, Whatsapp, MQTT and LDAP.
Fix some RX false positives.
Fix some "Uncommon TLS ALPN"-risk false positives.
Fix "confidence" value for some Zoom/Torrent classifications.
Minor fix in Lua script for Wireshark extcap.
Update .gitignore file.
Let GitHub correctly detect the language type of *.inc files.
Zattoo example has been provided by @subhajit-cdot in #1148.
