* 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.
When setting up the DPD info we previously would get the
`transport_proto` for the connection with `get_conn_transport_proto`.
This function takes a `conn_id` and would fail fatally if the connection
for the given ID was unknown. It seems it was possible to run into such
scenarios when the `analyzer_violation` event was processed after the
connection had been cleaned up.
We now get the `transport_proto` directly from the ports in the
`connection` passed into `analyzer_violation` via
`get_port_transport_proto` which cannot fail.
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.
This allows one to tune the number of protocol violations to tolerate
from any given analyzer type before just disabling a given instance
of it.
Also removes the "disabled_aids" field from the DPD::Info record
since it serves no purpose: in this case, calling disable_analyzer
multiple times for the same analyzer is a no-op.
