audit Subroutine

Purpose

Enables and disables system auditing.

Library

Standard C Library (libc.a)

Syntax

#include <sys/audit.h>

int audit ( Command, Argument) int Command; int Argument;

Description

The audit subroutine enables or disables system auditing.

When auditing is enabled, audit records are created for security-relevant events. These records can be collected through the auditbin (auditbin Subroutine) subroutine, or through the /dev/audit special file interface.

Parameters

Item	Description
Command	Defined in the sys/audit.h file, can be one of the following values: AUDIT_QUERY Returns a mask indicating the state of the auditing subsystem. The mask is a logical ORing of the AUDIT_ON, AUDIT_OFF, AUDIT_PANIC, and AUDIT_FULLPATH flags. AUDIT_ON Enables auditing. If auditing is already enabled, only the failure-mode behavior changes. The Argument parameter specifies recovery behavior in the event of failure and may be either 0 or the value AUDIT_PANIC or AUDIT_FULLPATH. Note: If AUDIT_PANIC is specified, bin-mode auditing must be enabled before the audit subroutine call. AUDIT_OFF Disables the auditing system if auditing is enabled. If the auditing system is disabled, the audit subroutine does nothing. The Argument parameter is ignored. AUDIT_RESET Disables the auditing system and resets the auditing system. If auditing is already disabled, only the system configuration is reset. Resetting the audit configuration involves clearing the audit events and audited objects table, and terminating bin auditing and stream auditing. AUDIT_EVENT_THRESHOLD Audit event records will be buffered until a total of Argument records have been saved, at which time the audit event records will be flushed to disk. An Argument value of zero disables this functionality. This parameter only applies to AIX® 4.1.4 and later. AUDIT_BYTE_THRESHOLD Audit event data will be buffered until a total of Argument bytes of data have been saved, at which time the audit event data will be flushed to disk. An Argument value of zero disables this functionality. This parameter only applies to AIX 4.1.4 and later.
Argument	Specifies the behavior when a bin write fails (for AUDIT_ON) or specifies the size of the audit event buffer (for AUDIT_EVENT_THRESHOLD and AUDIT_BYTE_THRESHOLD). For AUDIT_RESET and AUDIT_QUERY, the value of the Argument is the WPAR ID. For all other commands, the value of Argument is ignored. The valid values are: AUDIT_PANIC The operating system halts abruptly if an audit record cannot be written to a bin. Note: If AUDIT_PANIC is specified, bin-mode auditing must be enabled before the audit subroutine call. AUDIT_FULLPATH The operating system starts capturing full path name for the FILE_Open, FILE_Read, FILE_Write auditing events. BufferSize The number of bytes or audit event records which will be buffered. This parameter is valid only with the command AUDIT_BYTE_THRESHOLD and AUDIT_EVENT_THRESHOLD. A value of zero will disable either byte (for AUDIT_BYTE_THRESHOLD) or event (for AUDIT_EVENT_THRESHOLD) buffering.

Item

Description

Command

Defined in the sys/audit.h file, can be one of the following values:

AUDIT_QUERY: Returns a mask indicating the state of the auditing subsystem. The mask is a logical ORing of the AUDIT_ON, AUDIT_OFF, AUDIT_PANIC, and AUDIT_FULLPATH flags.
AUDIT_ON: Enables auditing. If auditing is already enabled, only the failure-mode behavior changes. The Argument parameter specifies recovery behavior in the event of failure and may be either 0 or the value AUDIT_PANIC or AUDIT_FULLPATH.
Note: If AUDIT_PANIC is specified, bin-mode auditing must be enabled before the audit subroutine call.
AUDIT_OFF: Disables the auditing system if auditing is enabled. If the auditing system is disabled, the audit subroutine does nothing. The Argument parameter is ignored.
AUDIT_RESET: Disables the auditing system and resets the auditing system. If auditing is already disabled, only the system configuration is reset. Resetting the audit configuration involves clearing the audit events and audited objects table, and terminating bin auditing and stream auditing.
AUDIT_EVENT_THRESHOLD: Audit event records will be buffered until a total of Argument records have been saved, at which time the audit event records will be flushed to disk. An Argument value of zero disables this functionality. This parameter only applies to AIX® 4.1.4 and later.
AUDIT_BYTE_THRESHOLD: Audit event data will be buffered until a total of Argument bytes of data have been saved, at which time the audit event data will be flushed to disk. An Argument value of zero disables this functionality. This parameter only applies to AIX 4.1.4 and later.

Argument

Specifies the behavior when a bin write fails (for AUDIT_ON) or specifies the size of the audit event buffer (for AUDIT_EVENT_THRESHOLD and AUDIT_BYTE_THRESHOLD). For AUDIT_RESET and AUDIT_QUERY, the value of the Argument is the WPAR ID. For all other commands, the value of Argument is ignored. The valid values are:

AUDIT_PANIC: The operating system halts abruptly if an audit record cannot be written to a bin.
Note: If AUDIT_PANIC is specified, bin-mode auditing must be enabled before the audit subroutine call.
AUDIT_FULLPATH: The operating system starts capturing full path name for the FILE_Open, FILE_Read, FILE_Write auditing events.
BufferSize: The number of bytes or audit event records which will be buffered. This parameter is valid only with the command AUDIT_BYTE_THRESHOLD and AUDIT_EVENT_THRESHOLD. A value of zero will disable either byte (for AUDIT_BYTE_THRESHOLD) or event (for AUDIT_EVENT_THRESHOLD) buffering.

Return Values

For a Command value of AUDIT_QUERY, the audit subroutine returns, upon successful completion, a mask indicating the state of the auditing subsystem. The mask is a logical ORing of the AUDIT_ON, AUDIT_OFF, AUDIT_PANIC, AUDIT_NO_PANIC, and AUDIT_FULLPATH flags. For any other Command value, the audit subroutine returns 0 on successful completion.

If the audit subroutine fails, a value of -1 is returned and the errno global variable is set to indicate the error.

Error Codes

The audit subroutine fails if either of the following is true:

Item	Description
EINVAL	The Command parameter is not one of AUDIT_ON, AUDIT_OFF, AUDIT_RESET, or AUDIT_QUERY.
EINVAL	The Command parameter is AUDIT_ON and the Argument parameter specifies values other than AUDIT_PANIC or AUDIT_FULLPATH.
EPERM	The calling process does not have root user authority.

Files

Item	Description
dev/audit	Specifies the audit pseudo-device from which the audit records are read.