This commit introduces parsing of the CertificateRequest message in the
TLS handshake. It introduces a new event ssl_certificate_request, as
well as a new function parse_distinguished_name, which can be used to
parse part of the ssl_certificate_request event parameters.
This commit also introduces a new policy script, which appends
information about the CAs a TLS server requests in the
CertificateRequest message, if it sends it.
This is a script-only change that unrolls File::Info records into
multiple files.log entries if the same file was seen over different
connections by single worker. Consequently, the File::Info record
gets the commonly used uid and id fields added. These fields are
optional for File::Info - a file may be analyzed without relation
to a network connection (e.g by using Input::add_analysis()).
The existing tx_hosts, rx_hosts and conn_uids fields of Files::Info
are not meaningful after this change and removed by default. Therefore,
files.log will have them removed, too.
The tx_hosts, rx_hosts and conn_uids fields can be revived by using the
policy script frameworks/files/deprecated-txhosts-rxhosts-connuids.zeek
included in the distribution. However, with v6.1 this script will be
removed.
Adds base/frameworks/telemetry with wrappers around telemetry.bif
and updates telemetry/Manager to support collecting metrics from
script land.
Add policy/frameworks/telemetry/log for logging of metrics data
into a new telemetry.log and telemetry_histogram.log and add into
local.zeek by default.
This improves the framework's handling of Zeek node stdout and stderr by
extending the (script-layer) Supervisor functionality.
- The Supervisor _either_ directs Zeek nodes' stdout/stderr to files _or_ lets
you hook into it at the script level. We'd like both: files make sense to allow
inspection outside of the framework, and the framework would benefit from
tapping into the streams e.g. for error context. We now provide the file
redirection functionality in the Supervisor, in addition to the hook
mechanism. The hook mechanism also builds up rolling windows of up to
100 lines (configurable) into stdout/stderr.
- The new Mangement::Supervisor::API::notify_node_exit event notifies
subscribers (agents, really) that a particular node has exited (and is possibly
being restarted by the Supervisor). The event includes the name of the node,
plus its recent stdout/stderr context.
This adds management/persistence.zeek to establish common configuration for log
rotation and persistent variable state. Log-writing Zeek processes initially
write locally in their working directory, and rotate into subdirectory
"log-queue" of the spool. Since agent and controller have no logger,
persistence.zeek puts in place compatible configurations for them.
Storage folders for Broker-backed tables and clusterized stores default to
subdirectories of the new Zeek-level state folder.
When setting the ZEEK_MANAGEMENT_TESTING environment variable, persistent state
is kept in the local directory, and log rotation remains disabled.
This also tweaks @loads a bit in favor of simply loading frameworks/management,
which is easier to keep track of.
This provides Broker-level plumbing that allows agents to reach out to their
managed Zeek nodes and collect responses.
As a first event, it establishes Management::Node::API::notify_agent_hello,
to notify the agent when the cluster node is ready to communicate.
Also a bit of comment rewording to replace use of "data cluster" with simply
"cluster", to avoid ambiguity with data nodes in SumStats, and expansion of
test-all-policy.zeek and related/dependent tests, since we're introducing new
scripts.
Documentation is missing and will be added in the next couple of hours.
* origin/topic/johanna/tls12-decryption: (24 commits)
TLS decryption: add test, fix small issues
Address PR feedback
TLS decryption: refactoring, more comments, less bare pointers
Small code fix and test baseline update.
SSL decryption: refactor TLS12_PRF
SSL decryption: small style changes, a bit of documentation
Deprecation and warning fixes
Clang-format updates
add missing call to EVP_KDF_CTX_set_params
TLS decryption: remove payload from ssl_encrypted_data again.
TLS 1.2 decryption: adapt OpenSSL 3.0 changes for 1.1
ssl: adapt TLS-PRF to openSSL 3.0
ssl/analyzer: potentially fix memory leaks caused by bytestrings
analyzer/ssl: several improvements
analyzer/ssl: defensive key length check + more debug logging
testing: feature gate ssl/decryption test
testing: add ssl/decryption test
analyzer/ssl: handle missing <openssl/kdf.h>
analyzer/ssl: silence warning in DTLS analyzer
analyzer/ssl: move proc-{client,server}-hello into the respective analyzers
...
- This gives the cluster controller and agent the common name "Management
framework" and changes the start directory of the sources from
"policy/frameworks/cluster" to "policy/frameworks/management". This avoids
ambiguity with the existing cluster framework.
- It renames the "ClusterController" and "ClusterAgent" script modules to
"Management::Controller" and "Management::Agent", respectively. This allows us
to anchor tooling common to both controller and agent at the "Management"
module.
- It moves common configuration settings, logging, requests, types, and
utilities to the common "Management" module.
- It removes the explicit "::Types" submodule (so a request/response result is
now a Management::Result, not a Management::Types::Result), which makes
typenames more readable.
- It updates tests that depend on module naming and full set of scripts.
This commit refactors TLS decryption, adds more comments in scripts and
in C++ source-code, and removes use of bare pointers, instead relying
more on stl data types.
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).
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.
Several limitations still apply:
- TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 is the only supported cipher suite
- Some tests are broken due to a failing assertion regarding bytestring
- No newly written tests for decryption (the patch was tested extensively for our paper)
- Several small open technical questions marked with FIXME
- Architecture in the ssl module might not be optimal
These are no longer loaded by default due to the performance impact they
cause simply by being loaded (they have event handlers for commonly
generated events) and they aren't generally useful enough to justify it.
This commit removed functions/events that have been deprecated in Bro
2.6. It also removes the detection code that checks if the old
communication framework is used (since all the functions that are
checked were removed).
Addresses parts of GH-243
