Security-relevant system actions can be audited. These auditable actions are defined as audit events. Audit events are listed in the /etc/security/audit_event file. Each audit event is defined in the file by an event number, a symbolic name, a short description, and the set of audit classes to which the event belongs. For more information on the audit_event file, see the audit_event(4) man page.
For example, the following entry defines the audit event for the exec() system call:
When you preselect for auditing either the audit class ps or the audit class ex, then exec() system calls are recorded in the audit trail.
Solaris auditing handles attributable and nonattributable events. Audit policy divides events into synchronous and asynchronous events. as follows:
Attributable events – Events that can be attributed to a user. The exec() system call can be attributed to a user, so the call is considered an attributable event. All attributable events are synchronous events.
Nonattributable events – Events that occur at the kernel-interrupt level or before a user is authenticated. The na audit class handles audit events that are nonattributable. For example, booting the system is a nonattributable event. Most nonattributable events are asynchronous events. However, nonattributable events that have associated processes, such as failed login, are synchronous events.
Synchronous events – Events that are associated with a process in the system. Synchronous events are the majority of system events.
Asynchronous events – Events that are not associated with any process, so no process is available to be blocked and later woken up. Initial system boot and PROM enter and exit events are examples of asynchronous events.
When the class to which an audit event belongs is preselected for auditing, the event is recorded in the audit trail. For example, when you preselect the ps and na audit classes for auditing, the exec() system calls and system boot actions, among other events, are recorded in the audit trail.
In addition to the audit events that are defined by the Solaris audit service, third-party applications can generate audit events. Audit event numbers from 32768 to 65535 are available for third-party applications.