This commit changes DPD matching for TLS connections. A one-sided match
is enough to enable DPD now.
This commit also removes DPD for SSLv2 connections. SSLv2 connections do
basically no longer happen in the wild. SSLv2 is also really finnicky to
identify correctly - there is very little data required to match it, and
basically all matches today will be false positives. If DPD for SSLv2 is
still desired, the optional signature in policy/protocols/ssl/dpd-v2.sig
can be loaded.
Fixes GH-1952
This policy script significantly extends the details that are logged
about SSL/TLS handshakes.
I am a bit tempted to just make this part of the default log - but it
does add a bunch logging overhead for each connection.
Extract-certs-pem writes pem files to a dedicated file; since it does
not really work in cluster-environments it was never super helpful.
This commit deprecates this file and, instead, adds
log-certs-base64.zeek, which adds the base64-encoded certificate (which
is basically equivalent with a PEM) to the log-file. Since, nowadays,
the log-files are deduplicates this should not add a huge overhead.
The ICSI notary is pretty much inactive. Furthermore - this approach
does no longer make much sense at this point of time - performing, e.g.,
signed certificate timestamp validation is much more worthwhile.
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.
The larger number was substracted from the smaller one leading to an
integer overflow. However, no information was lost due to everything
also being present in the notice message.
Fixes GH-1454
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.
* 'master' of https://github.com/mmguero-dev/zeek:
check for the existance of f?$conns in file_sniff event in policy/protocols/ssl/log-hostcerts-only.zeek
In using the corelight/bro-xor-exe-plugin (https://github.com/corelight/bro-xor-exe-plugin) I noticed this error when running the PCAP trace file in its tests directory:
1428602842.525435 expression error in /opt/zeek/share/zeek/policy/protocols/ssl/log-hostcerts-only.zeek, line 44: field value missing (X509::f$conns)
Examining log-hostcerts-only.zeek, I saw that although f$conns is being checked for length, it's not being checked to see if it exists first.
This commit changes "if ( |f$conns| != 1 )" to "if (( ! f?$conns ) || ( |f$conns| != 1 ))" so that the script returns if there is no f$conns field.
In my local testing, this seems to fix the error. My testing was being done with v3.0.5, but I think this patch can be applied to both the 3.0.x and 3.1.x branches.
* All "Broxygen" usages have been replaced in
code, documentation, filenames, etc.
* Sphinx roles/directives like ":bro:see" are now ":zeek:see"
* The "--broxygen" command-line option is now "--zeexygen"
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
...
log-hostcerts-only relied on old event ordering; the identifier key of
validate-certs is now shorter (no function change, just potentially a
tiny bit faster).
Move from using CCS (before: established) to just doing certificate
validation at the end of the connection.
This is (again) more robust in the case of aborted connection. I am
moving this into a hook because of the complexity of the
end-of-connection handling for SSL.
This should probably be extended to not just handle SSL validation, but
all other logging constructs that are currently called in _established.
These were caused by earlier code updates.
This commit also removes the ocsp stapling logging script; it was
defunctional and the information provided by it wnever really has been
especially interesting.
This triggers a re-validation of the SCT when the certificate validation
status changed. This means that a SCT will show as valid if the
certificate chain could be validated and can now be used to determine
the correct issuer key hash.
This also rewrites the certificate validation script (which we need for
this) slightly.
This could need a bit of caching, but should generally work very
reliably.
This is much more complex than the TLS Extension/OCSP cases. We need to
first alter the certificate and remove the extension from it, before
extracting the tbscert. Furthermore, we need the key hash of the issuing
certificate to be able to validate the proof - which means that we need
a valid certificate chain.
Missing: documentation, nice integration so that we can just add a
script and use this in Bro.