This moves c$service_violation to the deprecated-dpd-log policy script.
This is the only script in the distribution that uses the field, and it
is unlikely to be used externally. It is also responsible for a
significant amount of memory use by itself.
This also restores the field being populated, which was broken in
GH-4362
In the past, we used a default canonifier, which removes everything that
looks like a timestamp from log files. The goal of this is to prevent
logs from changing, e.g., due to local system times ending up in log
files.
This, however, also has the side-effect of removing information that is
parsed from protocols which probably should be part of our tests.
There is at least one test (1999 certificates) where the entire test
output was essentially removed by the canonifier.
GH-4521 was similarly masked by this.
This commit changes the default canonifier, so that only the first
timestamp in a line is removed. This should skip timestamps that are
likely to change while keeping timestamps that are parsed
from protocol information.
A pass has been made over the tests, with some additional adjustments
for cases which require the old canonifier.
There are some cases in which we probably could go further and not
remove timestamps at all - that, however, seems like a follow-up
project.
This field is used internally to trace which analyzers already had a
violation. This is mostly used to prevent duplicate logging.
In the past, c$service_violation was used for a similar purpose -
however it has slightly different semantics. Where c$failed_analyzers
tracks analyzers that were removed due to a violation,
c$service_violation tracks violations - and doesn't care if an analyzer
was actually removed due to it.
The main part of this commit are changes in tests. A lot of the tests
that previously relied on analyzer.log or dpd.log now use the new
analyzer-failed.log.
I verified all the changes and, as far as I can tell, everything
behaves as it should. This includes the external test baselines.
This change also enables logging of file and packet analyzer to
analyzer_failed.log and fixes some small behavior issues.
The analyzer_failed event is no longer raised when the removal of an
analyzer is vetoed.
If an analyzer is no longer active when an analyzer violation is raised,
currently the analyzer_failed event is raised. This can, e.g., happen
when an analyzer error happens at the very end of the connection. This
makes the behavior more similar to what happened in the past, and also
intuitively seems to make sense.
A bug introduced in the failed service logging was fixed.
This commit revamps the handling of analyzer violations that happen
before an analyzer confirms the protocol.
The current state is that an analyzer is disabled after 5 violations, if
it has not been confirmed. If it has been confirmed, it is disabled
after a single violation.
The reason for this is a historic mistake. In Zeek up to versions 1.5,
analyzers were unconditianally removed when they raised the first
protocol violation.
When this script was ported to the new layout for Zeek 2.0 in
b4b990cfb5, a logic error was introduced
that caused analyzers to no longer be disabled if they were not
confirmed.
This was the state for ~8 years, till the DPD::max_violations options
was added, which instates the current approach of disabling unconfirmed
analyzers after 5 violations. Sadly, there is not much discussion about
this change - from my hazy memory, I think this was discovered during
performance tests and the new behavior was added without checking into
the history of previous changes.
This commit reinstates the originally intended behavior of DPD. When an
analyzer that has not been confirmed raises a protocol violation, it is
immediately removed from the connection. This also makes a lot of sense
- this allows the analyzer to be in a "tasting" phase at the beginning
of the connection, and to error out quickly once it realizes that it was
attached to a connection not containing the desired protocol.
This change also removes the DPD::max_violations option, as it no longer
serves any purpose after this change. (In practice, the option remains
with an &deprecated warning, but it is no longer used for anything).
There are relatively minimal test-baseline changes due to this; they are
mostly triggered by the removal of the data structure and by less
analyzer errors being thrown, as unconfirmed analyzers are disabled
after the first error.
...the only known cases where the `-` for `connection$service` was
handled is to skip/ignore these analyzers.
Slight suspicion that join_string_set() should maybe become a bif
now determine_service() runs once for each connection.
Closes#2388
* Because frameworks/analyzer is loaded via init-frameworks-and-bifs the
dpd functionality (really just dpd.log and disabling of analyzers) is
now enabled even in bare mode.
* Not sure we need to keep frameworks/base/dpd/__load__.zeek around
or can just remove it right away.
This also updates all usages of the deprecated Val ctor to use
either IntervalVal, TimeVal, or DoubleVal ctors. The reason for
doing away with the old constructor is that using it with TYPE_INTERVAL
isn't strictly correct since there exists a more specific subclass,
IntervalVal, with overriden ValDescribe() method that ought to be used
to print such values in a more descriptive way.
And switch Zeek's base scripts over to using it in place of
"connection_state_remove". The difference between the two is
that "connection_state_remove" is raised for all events while
"successful_connection_remove" excludes TCP connections that were never
established (just SYN packets). There can be performance benefits
to this change for some use-cases.
There's also a new event called ``connection_successful`` and a new
``connection`` record field named "successful" to help indicate this new
property of connections.
