Security Event Audit is a facility to provide fine-grained, configurable
logging of security-relevant events, and is intended to meet the requirements
of the Common Criteria (CC) Common Access Protection Profile (CAPP)
evaluation.
The
Fx
facility implements the de facto industry standard BSM API, file
formats, and command line interface, first found in the Solaris operating
system.
Information on the user space implementation can be found in
libbsm(3).
Audit support is enabled at boot, if present in the kernel, using an
rc.conf5
flag.
The audit daemon,
auditd(8),
is responsible for configuring the kernel to perform
,
pushing
configuration data from the various audit configuration files into the
kernel.
Audit Special Device
The kernel
facility provides a special device,
/dev/audit
which is used by
auditd(8)
to monitor for
events, such as requests to cycle the log, low disk
space conditions, and requests to terminate auditing.
This device is not intended for use by applications.
Audit Pipe Special Devices
Audit pipe special devices, discussed in
auditpipe(4),
provide a configurable live tracking mechanism to allow applications to
tee the audit trail, as well as to configure custom preselection parameters
to track users and events in a fine-grained manner.
The
OpenBSM
implementation was created by McAfee Research, the security
division of McAfee Inc., under contract to Apple Computer Inc. in 2004.
It was subsequently adopted by the TrustedBSD Project as the foundation for
the OpenBSM distribution.
Support for kernel
first appeared in
Fx 6.2 .
AUTHORS
An -nosplit
This software was created by McAfee Research, the security research division
of McAfee, Inc., under contract to Apple Computer Inc.
Additional authors include
An Wayne Salamon ,
An Robert Watson ,
and SPARTA Inc.
The Basic Security Module (BSM) interface to audit records and audit event
stream format were defined by Sun Microsystems.
The
facility in
Fx is considered experimental, and production deployment should occur only after
careful consideration of the risks of deploying experimental software.
The
Fx kernel does not fully validate that audit records submitted by user
applications are syntactically valid BSM; as submission of records is limited
to privileged processes, this is not a critical bug.
Instrumentation of auditable events in the kernel is not complete, as some
system calls do not generate audit records, or generate audit records with
incomplete argument information.
Mandatory Access Control (MAC) labels, as provided by the
mac(4)
facility, are not audited as part of records involving MAC decisions.
