* 'topic/corelight/load-hook' of https://github.com/corelight/bro:
Fix and extend behavior of HookLoadFile
I refactored some parts of scan.l to avoid the ambiguity of some
branches returning 0 and some branches not returning anything.
This just skips over IPv6 nameserver addresses for now and uses the
first IPv4 one in the resolver config. Should be possible to support
IPv6, but that may need more testing (e.g. need to make sure the code
will be portable to various platforms).
The hook being added is:
bool HookReporter(const std::string& prefix, const EventHandlerPtr event,
const Connection* conn, const val_list* addl, bool location,
const Location* location1, const Location* location2,
bool time, const std::string& buffer) override;
This hook gives access to basically all information that is available in
the function in Reporter.cc that performs the logging. The hook is
called each time when anything passes through the reporter in the cases
in which an event usually would be called. This includes weirds. The
hook can return false to prevent the normal reporter events from being
raised.
This commit fixes and extends the behavior of HookLoadFile. Before this
change, HookLoadFile appended ".bro" to each path that was @loaded, even
if the path specified directory names. Furthermore it only gave the path
of the file as it was specified in the Bro script without revealing the
final path of the file that it was going to load.
This patch changes this behavior - in addition to giving the unmodified
path given in the @load command, the hook now returns the resolved path
of the file or directory it is going to load (if found). The hook is
furthermore raises for @load-sigs and @load-plugin; a enum specifies the
kind of load that is happening.
Increased the size of a buffer to be large enough to contain all the
characters of the largest possible "double" value when scientific
notation is not being used (previously, the nonsensical "NAN.0" would be
written to ASCII logs for any value >= 1e248).
In ContentLine_Analyzer, prevent excessively long lines being assembled.
The line length will default to just under 16MB, but can be overriden on
a per-analyzer basis. This is done for the finger,ident, and irc
analyzers.
handlers.
It's well known that changes to mutable event arguments, like tables,
become visible to all places where those values are used, including
subsequent handlers of the same event. However, there's a related case
that's more suprising: simply assigning *a new value* to an event
argument passes through, too. This commit fixes that behaviour. (We
even had a btest with a baseline reflecting the problen).
IP packets that have a header length that is greater than the total
length of the packet cause a integer overflow, which cause range-checks
to fail, which causes OOB reads.
Furthermore Bro does not currently check the version field of IP packets
that are read from tunnels. I added this check - otherwhise Bro reports
bogus IP information in its error messages, just converting the data
from the place where the IP information is supposed to be to IPs.
This behavior brings us closer to what other software (e.g. Wireshark)
displays in these cases.
A combination of packets can trigger an out of bound write of '0' byte
in the content-line analyzer.
This bug was found by Frank Meier.
Addresses BIT-1856.
This patch adds a "scripts" option to -B, when Bro is enabled with
--enable-debug. This option will output information about the scripts
that are loaded to debug.log, showing their exact load order.
Signatures using an eval-condition that had no return value caused a
segmentation fault. This fix just returns false in this case, as it is
done for an interpreter error.
set_processing_status can be called before reporter is initialized or
after it is deleted. Work around by sending data to stderr instead.
Patch by Thomas Petersen.
The connsize bifs used to output a reporter message when they could not
find the associated connection. This patch disables this message; it is
not useful and can happen during normal operation when trying to use
thresholding on short-lived connections. This case is still reported by
the boolean value that the respective functions return.
This switches in from using strstr to use strnstr (implementation from
FreeBSD on systems which do not bring their own implementation).
It is especially likely that users come accross this when using the
DATA_EVENT analyzer with files that contain binary data - the test uses
exactly this case.
From the OpenSSH 7.4 changelog:
sshd(8), ssh(1): Support the "curve25519-sha256" key exchange
method. This is identical to the currently-supported method named
"curve25519-sha256@libssh.org".
It turns out that the serial number field in all events was never
populated correctly. Instead, the previous field (issuer key hash) was
re-read and repeated in all events.
It turns out that Chrome supports an experimental mode to support TLS
1.3, which uses a non-standard way to negotiate TLS 1.3 with a server.
This non-standard way to negotiate TLS 1.3 breaks the current draft RFC
and re-uses an extension on the server-side with a different binary
formatting, causing us to throw a binpac exception.
This patch ignores the extension when sent by the server, continuing to
correctly parse the server_hello reply (as far as possible).
From what I can tell this seems to be google working around the fact
that MITM equipment cannot deal with TLS 1.3 server hellos; this change
makes the fact that TLS 1.3 is used completely opaque unless one looks
into a few extensions.
We currently log this as TLS 1.2.
This adds a slight patch to the HTTP analyzer, which recognizez when a connection is
upgraded to a different protocol (using a 101 reply with a few specific headers being
set).
In this case, the analyzer stops further processing of the connection (which will
result in DPD errors) and raises a new event:
event http_connection_upgrade(c: connection, protocol: string);
Protocol contains the name of the protocol that is being upgraded to, as specified in
one of the header values.
Closes#1830.
* origin/topic/johanna/ocsp-sct-validate: (82 commits)
Tiny script changes for SSL.
Update CT Log list
SSL: Update OCSP/SCT scripts and documentation.
Revert "add parameter 'status_type' to event ssl_stapled_ocsp"
Revert "parse multiple OCSP stapling responses"
SCT: Fix script error when mime type of file unknown.
SCT: another memory leak in SCT parsing.
SCT validation: fix small memory leak (public keys were not freed)
Change end-of-connection handling for validation
OCSP/TLS/SCT: Fix a number of test failures.
SCT Validate: make caching a bit less aggressive.
SSL: Fix type of ssl validation result
TLS-SCT: compile on old versions of OpenSSL (1.0.1...)
SCT: Add caching support for validation
SCT: Add signed certificate timestamp validation script.
SCT: Allow verification of SCTs in Certs.
SCT: only compare correct OID/NID for Cert/OCSP.
SCT: add validation of proofs for extensions and OCSP.
SCT: pass timestamp as uint64 instead of time
Add CT log information to Bro
...
I added another small change - since we are inlining Configure(), we can
just set bro_plugin directly to BRO_PLUGIN_BRO_VERSION in
src/plugin/Plugin.h, instead of depending on the plugin to do it. This
also means we do not need to change init-plugin in bro-aux at this
moment.
BIT-1828 #closed
* origin/topic/robin/plugin-version-check:
Adding plugin API number into versioned function name, and removing old runtime API version check.
Extend plugin infrastructure to catch Bro version mismatches at link time.
time.
People keep running into the problem that they upgrade Bro but forget
to recompile their plugins--which can lead to crashes. While the
plugins' API version was supposed to catch this, it's not reliable as
that check may come too late. This change takes a different tack: We
compile a C function into the Bro binary that has Bro's version number
encoded into its name. A plugin can then reference that function. If
the Bro version changes, the function goes away and the plugin won't
load anymore.
I've integrated that function reference into the plugin skeleton code
so that new plugins get it automatically (unless explicitly removed).
I couldn't see a way to do it transparently for already existing
plugins unfortunately.
The version number used for the function name is slightly normalized
to skip any git revision postfixes (i.e., "2.5-xxx" is always treated
as "2.5-git") so that one doesn't need to recompile all plugins after
every master commit. That seems good enough, usually people run into
this when upgrading to a new release.
If one loads an old plugin into a new Bro, the error message looks
like this:
$ bro -NN Demo::Foo
fatal error in /home/robin/bro/master/scripts/base/init-bare.bro, line 1:
cannot load plugin library /home/robin/tmp/p/build//lib/Demo-Foo.linux-x86_64.so:
/home/robin/tmp/p/build//lib/Demo-Foo.linux-x86_64.so: undefined symbol: bro_version_2_5_git_debug
Not the prettiest, but better than a crash!
TODO: I'm still unsure if we should remove the plugin API version
altogetger now. This link-time check should catch everything the API
version does, except for master commits.
