Use `NDPI_OBFUSCATED_TRAFFIC` instead; this way, all the obfuscated
traffic is identified via `NDPI_OBFUSCATED_TRAFFIC` flow risk.
Disable fully-encryption detection by default, like all the obfuscation
heuristics.
In some scenarios, you might not be interested in flow metadata or
flow-risks at all, but you might want only flow (sub-)classification.
Examples: you only want to forward the traffic according to the
classification or you are only interested in some protocol statistics.
Create a new configuration file (for `ndpiReader`, but you can trivially
adapt it for the library itself) allowing exactly that. You can use it
via: `ndpiReader --conf=example/only_classification.conf ...`
Note that this way, the nDPI overhead is lower because it might need
less packets per flow:
* TLS: nDPI processes only the CH (in most cases) and not also the SH
and certificates
* DNS: only the request is processed (instead of both request and
response)
We might extend the same "shortcut-logic" (stop processing the flow
immediately when there is a final sub-classification) for others
protocols.
Add the configuration options to enable/disable the extraction of some
TLS metadata.
Last step of removing JA3C fingerprint
Remove some duplicate tests: testing with ja4c/ja3s disabled is already
performed by `disable_metadata_and_flowrisks` configuration.
Close:#2551
Allow nDPI to process the entire flows and not only the first N packets.
Usefull when the application is interested in some metadata spanning the
entire life of the session.
As initial step, only STUN flows can be put in monitoring.
See `doc/monitoring.md` for further details.
This feature is disabled by default.
Close#2583
Add configurable options for whether to include client port or client IP
in the flow's protocol guesses. This defaults to include both client
port/IP if the protocol is not guessed with the server IP/port.
This is intended for when flow direction detection is enabled, so we
know that sport = client port, dport = server port.
Based on the paper: "Fingerprinting Obfuscated Proxy Traffic with
Encapsulated TLS Handshakes".
See: https://www.usenix.org/conference/usenixsecurity24/presentation/xue-fingerprinting
Basic idea:
* the packets/bytes distribution of a TLS handshake is quite unique
* this fingerprint is still detectable if the handshake is
encrypted/proxied/obfuscated
All heuristics are disabled by default.
Based on the paper: "OpenVPN is Open to VPN Fingerprinting"
See: https://www.usenix.org/conference/usenixsecurity22/presentation/xue-diwen
Basic idea:
* the distribution of the first byte of the messages (i.e. the distribution
of the op-codes) is quite unique
* this fingerprint might be still detectable even if the OpenVPN packets are
somehow fully encrypted/obfuscated
The heuristic is disabled by default.
Allow sub-classification of OpenVPN/Wireguard flows using their server IP.
That is useful to detect the specific VPN application/app used.
At the moment, the supported protocols are: Mullvad, NordVPN, ProtonVPN.
This feature is configurable.
After a flow has been classified as RTP or RTCP, nDPI might analyse more
packets to look for STUN/DTLS packets, i.e. to try to tell if this flow
is a "pure" RTP/RTCP flow or if the RTP/RTCP packets are multiplexed with
STUN/DTLS.
Useful for proper (sub)classification when the beginning of the flows
are not captured or if there are lost packets in the the captured traffic.
Disabled by default
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.
Enable parsing of Mapped-Address attribute for all STUN flows: that
means that STUN classification might require more packets.
Add a configuration knob to enable/disable this feature.
Note that we can have (any) STUN metadata also for flows *not*
classified as STUN (because of DTLS).
Add support for ipv6.
Restore the correct extra dissection logic for Telegram flows.
Add the concept of "global context".
Right now every instance of `struct ndpi_detection_module_struct` (we
will call it "local context" in this description) is completely
independent from each other. This provide optimal performances in
multithreaded environment, where we pin each local context to a thread,
and each thread to a specific CPU core: we don't have any data shared
across the cores.
Each local context has, internally, also some information correlating
**different** flows; something like:
```
if flow1 (PeerA <-> Peer B) is PROTOCOL_X; then
flow2 (PeerC <-> PeerD) will be PROTOCOL_Y
```
To get optimal classification results, both flow1 and flow2 must be
processed by the same local context. This is not an issue at all in the far
most common scenario where there is only one local context, but it might
be impractical in some more complex scenarios.
Create the concept of "global context": multiple local contexts can use
the same global context and share some data (structures) using it.
This way the data correlating multiple flows can be read/write from
different local contexts.
This is an optional feature, disabled by default.
Obviously data structures shared in a global context must be thread safe.
This PR updates the code of the LRU implementation to be, optionally,
thread safe.
Right now, only the LRU caches can be shared; the other main structures
(trees and automas) are basically read-only: there is little sense in
sharing them. Furthermore, these structures don't have any information
correlating multiple flows.
Every LRU cache can be shared, independently from the others, via
`ndpi_set_config(ndpi_struct, NULL, "lru.$CACHE_NAME.scope", "1")`.
It's up to the user to find the right trade-off between performances
(i.e. without shared data) and classification results (i.e. with some
shared data among the local contexts), depending on the specific traffic
patterns and on the algorithms used to balance the flows across the
threads/cores/local contexts.
Add some basic examples of library initialization in
`doc/library_initialization.md`.
This code needs libpthread as external dependency. It shouldn't be a big
issue; however a configure flag has been added to disable global context
support. A new CI job has been added to test it.
TODO: we should need to find a proper way to add some tests on
multithreaded enviroment... not an easy task...
*** API changes ***
If you are not interested in this feature, simply add a NULL parameter to
any `ndpi_init_detection_module()` calls.
Some changes in the parameters names.
Add a fuzzer to fuzz the configuration file format.
Add the infrastructure to configuratin callbacks.
Add an helper to map LRU cache indexes to names.
