Notable changes:
- libmagic is no longer used at all. All MIME type detection is
done through new Bro signatures, and there's no longer a means to get
verbose file type descriptions (e.g. "PNG image data, 1435 x 170").
The majority of the default file magic signatures are derived
from the default magic database of libmagic ~5.17.
- File magic signatures consist of two new constructs in the
signature rule parsing grammar: "file-magic" gives a regular
expression to match against, and "file-mime" gives the MIME type
string of content that matches the magic and an optional strength
value for the match.
- Modified signature/rule syntax for identifiers: they can no longer
start with a '-', which made for ambiguous syntax when doing negative
strength values in "file-mime". Also brought syntax for Bro script
identifiers in line with reality (they can't start with numbers or
include '-' at all).
- A new Built-In Function, "file_magic", can be used to get all
file magic matches and their corresponding strength against a given
chunk of data
- The second parameter of the "identify_data" Built-In Function
can no longer be used to get verbose file type descriptions, though it
can still be used to get the strongest matching file magic signature.
- The "file_transferred" event's "descr" parameter no longer
contains verbose file type descriptions.
- The BROMAGIC environment variable no longer changes any behavior
in Bro as magic databases are no longer used/installed.
- Reverted back to minimum requirement of CMake 2.6.3 from 2.8.0
(it's back to being the same requirement as the Bro v2.2 release).
The bump was to accomodate building libmagic as an external project,
which is no longer needed.
Addresses BIT-1143.
Includes:
- Cleanup of the plugin API, in particular generally changing
const char* to std::string
- Renaming environment variable BRO_PLUGINS to BRO_PLUGIN_PATH,
defaulting to <prefix>/lib/bro/plugins
- Reworking how dynamic plugins are searched and activated. See
doc/devel/plugins.rst for details.
- New @load-plugin directive to explicitly activate a plugin
- Support for Darwin. (Linux untested right now)
- The init-plugin updates come with support for "make test", "make
sdist", and "make bdist" (see how-to).
- Test updates.
Notes: The new hook mechanism, which allows plugins to hook into Bro's
core a well-defined points, is still essentially untested.
- Move more functionality into base class.
- Remove cctors and assignment operators (weren't actually needed anymore)
- Switch from const char* to std::string.
A bunch of infrastructure work to move IOSource, IOSourceRegistry (now
iosource::Manager) and PktSrc/PktDumper code into iosource/, and over
to a plugin structure.
Other IOSources aren't touched yet, they are still in src/*.
It compiles and does something with a small trace, but that's all I've
tested so far. There are quite certainly a number of problems left, as
well as various TODOs and cleanup; and nothing's cast in stone yet.
Will continue to work on this.
This is essentially the code from the dynamic-plugin branch except for
some pieces that I have split out into separate, earlier commits.
I'm going to updatre things in this branch going forward.
Replaced some with InternalWarning or InternalAnalyzerError, the later
being a new method which signals the analyzer to not process further
input. Some usages I just removed if they didn't make sense or clearly
couldn't happen. Also did some minor refactors of related code while
reviewing/exploring ways to get rid of InternalError usages.
Also, for TCP content file write failures there's a new event:
"contents_file_write_failure".
It was getting too bloated and allocated memory in ways that were
difficult to understand how to manage. Separated out primarily in to
new find_file() and open_file()/open_package() functions.
Also renamed other util functions for path-related things.
Doesn't generate any docs, but it's hooked in to all places needed to
gather the necessary stuff w/ significantly less coupling than before.
The gathering now always occurs unconditionally to make documentation
available at runtime and a command line switch (-X) only toggles whether
to output docs to disk (reST format).
Should also improve the treatment of type name aliasing which wasn't a
big problem in practice before, but I think it's more correct now:
there's now a distinct BroType for each alias, but extensible types
(record/enum) will automatically update the types for aliases on redef.
Other misc refactoring of note:
- Removed a redundant/unused way of declaring event types.
- Changed type serialization format/process to preserve type name
information and remove compatibility code (since broccoli will
have be updated anyway).
* origin/topic/seth/faf-updates: (27 commits)
Undoing the FTP tests I updated earlier.
Update the last two btest FAF tests.
File analysis fixes and test updates.
Fix a bug with getting analyzer tags.
A few test updates.
Some tests work now (at least they all don't fail anymore!)
Forgot a file.
Added protocol description functions that provide a super compressed log representation.
Fix a bug where orig file information in http wasn't working right.
Added mime types to http.log
Clean up queued but unused file_over_new_connections event args.
Add jar files to the default MHR lookups.
Adding CAB files for MHR checking.
Improve malware hash registry script.
Fix a small issue with finding smtp entities.
Added support for files to the notice framework.
Make the custom libmagic database a git submodule.
Add an is_orig parameter to file_over_new_connection event.
Make magic for emitting application/msword mime type less strict.
Disable more libmagic builtin checks that override the magic database.
...
Conflicts:
doc/scripts/DocSourcesList.cmake
scripts/base/init-bare.bro
scripts/test-all-policy.bro
testing/btest/Baseline/coverage.bare-load-baseline/canonified_loaded_scripts.log
testing/btest/Baseline/coverage.default-load-baseline/canonified_loaded_scripts.log
- Several places were just using old variable names or not loading
scripts correctly after they'd been renamed/moved.
- Revert/adjust a change in how HTTP file handles are generated that
broke partial content responses.
- Turn some libmagic builtin checks back on; seems some are actually
useful (e.g. text detection seems to be a builtin). The rule going
forward probably will be only to turn off a builtin if we confirm it
causes issues.
- Removed some tests that are redundant or not necessary anymore because
the generic file analysis tests cover them.
- A couple FTP tests still fail that I think need an actual solution via
script changes.
It was previously not possible to crank the wheel on the PRNG in a
deterministic way without affecting the globally unique seed. The new extra
utility function bro_prng takes a state in the form of a long int and returns
the new PRNG state, now allowing arbitrary code parts to use the random number
functionality.
This commit also fixes a problem in the H3 constructor, which requires use
of multiple seeds. The single seed passed in now serves as seed to crank out as
many value needed using bro_prng.
Thanks to git this merge was less troublesome that I was afraid it
would be. Not all tests pass yet though (and file hashes have changed
unfortunately).
Conflicts:
cmake
doc/scripts/DocSourcesList.cmake
scripts/base/init-bare.bro
scripts/base/protocols/ftp/main.bro
scripts/base/protocols/irc/dcc-send.bro
scripts/test-all-policy.bro
src/AnalyzerTags.h
src/CMakeLists.txt
src/analyzer/Analyzer.cc
src/analyzer/protocol/file/File.cc
src/analyzer/protocol/file/File.h
src/analyzer/protocol/http/HTTP.cc
src/analyzer/protocol/http/HTTP.h
src/analyzer/protocol/mime/MIME.cc
src/event.bif
src/main.cc
src/util-config.h.in
testing/btest/Baseline/coverage.bare-load-baseline/canonified_loaded_scripts.log
testing/btest/Baseline/coverage.default-load-baseline/canonified_loaded_scripts.log
testing/btest/Baseline/istate.events-ssl/receiver.http.log
testing/btest/Baseline/istate.events-ssl/sender.http.log
testing/btest/Baseline/istate.events/receiver.http.log
testing/btest/Baseline/istate.events/sender.http.log
Some of the unit tests revealed different versions of libmagic could
give different mime types for the same input file and magic database.
One way that could happen is because of the use of hardcoded/builtin
token (word) comparisons for ascii files -- MAGIC_NO_CHECK_TOKENS flag
will prevent that from being used (and it's obsoleted in newer
libmagics).
The other problem looked like a bug fixed as of 5.05 where
a match in the magic database that doesn't have a verbose description
but does have a mime type won't actually return that mime type due to
the the missing description. The one case where that kept popping up
was in 5.04 not beign able to identify application/x-dosexec, so I added
a description to the top-level match for that to workaround the issue.
- It's derived from the magic database of libmagic 5.14, but with most
everything not related to mime types removed.
- The custom database is always used by default for mime detection, but
the more verbose file type detection will fall back on the default
libmagic installation's database. The result is: mime type strings
are now guaranteed to be consistent across platforms, but the verbose
file type descriptions are not.
- The custom database gets installed in $prefix/share/bro/magic, and
should even be extensible if files with new patterns are added inside
the directory.
- The search path for the mime magic database can be controlled via
BROMAGIC environment variable.
- Remove mime_desc field from ftp.log.
- Stop using the mime/file type canonifier with unit tests.
- libmagic >= 5.04 is now a requirement.
This is a larger internal change that moves the analyzer
infrastructure to a more flexible model where the available analyzers
don't need to be hardcoded at compile time anymore. While currently
they actually still are, this will in the future enable external
analyzer plugins. For now, it does already add the capability to
dynamically enable/disable analyzers from script-land, replacing the
old Analyzer::Available() methods.
There are three major parts going into this:
- A new plugin infrastructure in src/plugin. This is independent
of analyzers and will eventually support plugins for other parts
of Bro as well (think: readers and writers). The goal is that
plugins can be alternatively compiled in statically or loadead
dynamically at runtime from a shared library. While the latter
isn't there yet, there'll be almost no code change for a plugin
to make it dynamic later (hopefully :)
- New analyzer infrastructure in src/analyzer. I've moved a number
of analyzer-related classes here, including Analyzer and DPM;
the latter now renamed to Analyzer::Manager. More will move here
later. Currently, there's only one plugin here, which provides
*all* existing analyzers. We can modularize this further in the
future (or not).
- A new script interface in base/framework/analyzer. I think that
this will eventually replace the dpm framework, but for now
that's still there as well, though some parts have moved over.
I've also remove the dpd_config table; ports are now configured via
the analyzer framework. For exmaple, for SSH:
const ports = { 22/tcp } &redef;
event bro_init() &priority=5
{
...
Analyzer::register_for_ports(Analyzer::ANALYZER_SSH, ports);
}
As you can see, the old ANALYZER_SSH constants have more into an enum
in the Analyzer namespace.
This is all hardly tested right now, and not everything works yet.
There's also a lot more cleanup to do (moving more classes around;
removing no longer used functionality; documenting script and C++
interfaces; regression tests). But it seems to generally work with a
small trace at least.
The debug stream "dpm" shows more about the loaded/enabled analyzers.
A new option -N lists loaded plugins and what they provide (including
those compiled in statically; i.e., right now it outputs all the
analyzers).
This is all not cast-in-stone yet, for some things we need to see if
they make sense this way. Feedback welcome.
Added the file extraction action and did other misc. cleanup. Most of
the minimal core features/support for file analysis should be working at
this point, just have to start fleshing things out.
