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.
* logging is instead redirected to `ndpi_debug_printf`
Signed-off-by: lns <matzeton@googlemail.com>
Signed-off-by: Toni Uhlig <matzeton@googlemail.com>
The host automa is used for two tasks:
* protocol sub-classification (obviously);
* DGA evaluation: the idea is that if a domain is present in this
automa, it can't be a DGA, regardless of its format/name.
In most dissectors both checks are executed, i.e. the code is something
like:
```
ndpi_match_host_subprotocol(..., flow->host_server_name, ...);
ndpi_check_dga_name(..., flow->host_server_name,...);
```
In that common case, we can perform only one automa lookup: if we check the
sub-classification before the DGA, we can avoid the second lookup in
the DGA function itself.
* CI fixes
* some build systems do not like that (e.g. OpenWrt)
* fixed some rrdtool related build warnings/errors
Signed-off-by: Toni Uhlig <matzeton@googlemail.com>
* Removed Visual Studio leftovers. Maintaining an autotools project with VS integration requires some additional overhead.
Signed-off-by: Toni Uhlig <matzeton@googlemail.com>
Signed-off-by: lns <matzeton@googlemail.com>
* build: update m4/ax_pthread.m4 from serial 23 -> serial 31
Update ax_pthread.m4 to the latest version from the autoconf-archive
project.
Signed-off-by: Sam James <sam@gentoo.org>
* build: properly detect AR, CC, RANLIB
It's necessary to be able to override choice of AR/CC/RANLIB and other toolchain
variables/tools for cross-compilation, testing with other toolchains, and
to ensure the compiler chosen by the user is actually used for the build.
Previously, GNU_PREFIX was kind-of used for this but this isn't a standard
variable (at all) and it wasn't applied consistently anyway.
We now use the standard autoconf mechanisms for finding these tools.
(RANLIB is already covered by LT_INIT.)
Signed-off-by: Sam James <sam@gentoo.org>
* build: use $(MAKE)
This ensures that parallel make works correctly, as otherwise, a fresh
make job will be started without the jobserver fd, and hence
not know about its parent, forcing -j1.
* build: respect CPPFLAGS, LDFLAGS
- CPPFLAGS is for the C preprocessor (usually for setting defines)
- LDFLAGS should be placed before objects for certain flags to work
(e.g. -Wl,--as-needed)
Signed-off-by: Sam James <sam@gentoo.org>
Co-authored-by: Luca Deri <lucaderi@users.noreply.github.com>
* Added ARM build and unit test run for SonarCloud-CI.
Signed-off-by: Toni Uhlig <matzeton@googlemail.com>
* Fixed Mingw64 build.
* adapted to SonarCloud-CI workflow
* removed broken and incomplete Windows example (tested on VS2017/VS2019)
* removed unnecessary include (e.g. pthread.h for the library which does not make use of it)
Signed-off-by: Toni Uhlig <matzeton@googlemail.com>
* Implement dga evaluation helper.
* Add test set for DGA classification.
* Add DGA classification performances tracking as part of Travis.
* Add DGA evaluation doc.
* Fix CI on OSX.
* Add missing backquote.
