While we support initializing records via coercion from an expression
list, e.g.,
local x: X = [$x1=1, $x2=2];
this can sometimes obscure the code to readers, e.g., when assigning to
value declared and typed elsewhere. The language runtime has a similar
overhead since instead of just constructing a known type it needs to
check at runtime that the coercion from the expression list is valid;
this can be slower than just writing the readible code in the first
place, see #4559.
With this patch we use explicit construction, e.g.,
local x = X($x1=1, $x2=2);
The added disable-certificate-events-known-certs.zeek disables repeated
X509 events in SSL connections, given that the connection terminates at
the same server and used the samt SNI as a previously seen connection
with the same certificate.
For people that see significant amounts of TLS 1.2 traffic, this could
reduce the amount of raised events significantly - especially when a
lot of connections are repeat connections to the same servers.
The practical impact of not raising these events is actually very little
- unless a script directly interacts with the x509 events, everything
works as before - the x509 variables in the connection records are still
being set (from the cache).
By default, each certificate is now output only once per hour. This also
should work in cluster mode, where we use the net broker-table-syncing
feature to distribute the information about already seen certificates
across the entire cluster.
Log caching is also pretty configureable and can be changed using a
range of confiuration options and hooks.
Note that this is currently completely separate from X509 events
caching, which prevents duplicate parsing of X509 certificates.
This commit changes the SSL and X.509 logging formats to something that,
hopefully, slowly approaches what they will look like in the future.
X.509 log is not yet deduplicated; this will come in the future.
This commit introduces two new options, which determine if certificate
issuers and subjects are still logged in ssl.log. The default is to have
the host subject/issuer logged, but to remove client-certificate
information. Client-certificates are not a typically used feature
nowadays.
In the past I thought that this is not super interesting. However, it
turns out that this can actually contain a slew of interresting
information - like operating systems querying for the revocation of
software signing certificates, e.g.
So - let's just enable this as a default log for the future.
This adds a "policy" hook into the logging framework's streams and
filters to replace the existing log filter predicates. The hook
signature is as follows:
hook(rec: any, id: Log::ID, filter: Log::Filter);
The logging manager invokes hooks on each log record. Hooks can veto
log records via a break, and modify them if necessary. Log filters
inherit the stream-level hook, but can override or remove the hook as
needed.
The distribution's existing log streams now come with pre-defined
hooks that users can add handlers to. Their name is standardized as
"log_policy" by convention, with additional suffixes when a module
provides multiple streams. The following adds a handler to the Conn
module's default log policy hook:
hook Conn::log_policy(rec: Conn::Info, id: Log::ID, filter: Log::Filter)
{
if ( some_veto_reason(rec) )
break;
}
By default, this handler will get invoked for any log filter
associated with the Conn::LOG stream.
The existing predicates are deprecated for removal in 4.1 but continue
to work.
Changed some configuration defaults to potentially more same values.
The callback function is now a hook to allow costomization of the events
that are raised.
Tests now exist. Test baselines are updated.
I moved the replay function to a callback - which now means that the replayed
functions are called before file_state remove. Which makes this virtually
identical with the events raised by the core.
Currently this is mostly missing tests, leak-testing and performance-tests.
This approach mostly relies on script-level changes. In scriptland, we track
which certificates should be cached - and also perform the caching and the
replaying of events there.
This actually is probably nearly functional - the problem is the fact that now
the event ordering is wrong - and file_state_remove is called before the x509
events are thrown.
The fix probably is to move to a callback from the core - which can execute
things in the right order again. (Or just write the whole event-raising inside
the core - but that is both less flexible and a lot more cumbersome).
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
...
Re-enable logging, now in policy because it probably is interesting to
no-one. We also only log ocsp replies.
Fix all tests.
Fix an issue where ocsp replies were added to the x.509 certificate
list.
This makes it much easier for protocols where the mime type is known in
advance like, for example, TLS. We now do no longer have to perform deep
script-level magic.
Instead of having an additional string argument specifying if we are
sending a request or a reply, we now have an ANALYZER_OCSP_REQUEST and
an ANALYZER_OCSP_REPLY
Instead of having a big event, that tries to parse all the data into a
huge datastructure, we do the more common thing and use a series of
smaller events to parse requests and responses.
The new events are:
ocsp_request -> raised for an ocsp request, giving version and requestor
ocsp_request_certificate -> raised n times per request, once per cert
ocsp_response_status -> raised for each ocsp response, giving status
ocsp_response_bytes -> raised for each ocsp response with information
ocsp_response_certificate -> raised for each cert in an ocsp response
* origin/topic/seth/more-file-type-ident-fixes:
File API updates complete.
Fixes for file type identification.
API changes to file analysis mime type detection.
Make HTTP 206 reassembly require ETags by default.
More file type identification improvements
Fix an issue with files having gaps before the bof_buffer is filled.
Fix an issue with packet loss in http file reporting.
Adding WOFF fonts to file type identification.
Extended JSON matching and added OCSP responses.
Another large signature update.
More signature updates.
Even more file type ident clean up.
Lots of fixes for file type identification.
BIT-1368 #merged
This allows the path for the default filter to be specified explicitly
when creating a stream and reduces the need to rely on the default path
function to magically supply the path.
The default path function is now only used if, when a filter is added to
a stream, it has neither a path nor a path function already.
Adapted the existing Log::create_stream calls to explicitly specify a
path value.
Addresses BIT-1324
- Plain text now identified with BOMs for UTF8,16,32
(even though 16 and 32 wouldn't get identified as plain text, oh-well)
- X.509 certificates are now populating files.log with
the mime type application/pkix-cert.
- File signatures are split apart into file types
to help group and organize signatures a bit better.
- Normalized some FILE_ANALYSIS debug messages.
- Improved Javascript detection.
- Improved HTML detection.
- Removed a bunch of bad signatures.
- Merged a bunch of signatures that ultimately detected
the same mime type.
- Added detection for MS LNK files.
- Added detection for cross-domain-policy XML files.
- Added detection for SOAP envelopes.
* origin/topic/bernhard/file-analysis-x509:
Forgot the preamble for the new leak test
(hopefully) last change -> return real opaque vec instead of any_vec
Fix dump-events - it cannot be used with ssl anymore, because openssl does not give the same string results in all versions.
Finishing touches of the x509 file analyzer.
Revert change to only log certificates once per hour.
Change x509 log - now certificates are only logged once per hour.
Fix circular reference problem and a few other small things.
X509 file analyzer nearly done. Verification and most other policy scripts work fine now.
Add verify functionality, including the ability to get the validated chain. This means that it is now possible to get information about the root-certificates that were used to secure a connection.
Second try on the event interface.
Backport crash fix that made it into master with the x509_extension backport from here.
Make x509 certificates an opaque type
rip out x509 code from ssl analyzer. Note that since at the moment the file analyzer does not yet re-populate the info record that means quite a lot of information is simply not available.
parse out extension. One event for general extensions (just returns the openssl-parsed string-value), one event for basicconstraints (is a certificate a CA or not) and one event for subject-alternative-names (only DNS parts).
Very basic file-analyzer for x509 certificates. Mostly ripped from the ssl-analyzer and the topic/bernhard/x509 branch.
Add parsing of several more types to SAN extension.
Make error messages of x509 file analyzer more useful.
Fix file ID generation.
You apparently have to be very careful which EndOfFile function of
the file analysis framework you call... otherwhise it might try
to close another file id. This took me quite a while to find.
addresses BIT-953, BIT-760, BIT-1150
SSL::Info now holds a reference to Files::Info instead of the
fa_files record.
Everything should work now, if everyone thinks that the interface is
ok I will update the test baselines in a bit.
addresses BIT-953, BIT-760
work fine now.
Todo:
* update all baselines
* fix the circular reference to the fa_file structure I introduced :)
Sadly this does not seem to be entirely straightforward.
addresses BIT-953, BIT-760
chain. This means that it is now possible to get information about the
root-certificates that were used to secure a connection.
Intermediate commit before changing the script interface again.
addresses BIT-953, BIT-760
openssl-parsed string-value), one event for basicconstraints (is a certificate
a CA or not) and one event for subject-alternative-names (only DNS parts).
the ssl-analyzer and the topic/bernhard/x509 branch.
Simply prints information about the encountered certificates (I have
not yet my mind up, what I will log...).
Next step: extensions...
