AU_PRESELECT(3BSM) Security and Auditing Library Functions AU_PRESELECT(3BSM)


NAME


au_preselect - preselect an audit event

SYNOPSIS


cc [ flag... ] file... -lbsm -lsocket -lnsl [ library... ]
#include <bsm/libbsm.h>

int au_preselect(au_event_t event, au_mask_t *mask_p, int sorf, int flag);


DESCRIPTION


The au_preselect() function determines whether the audit event event is
preselected against the binary preselection mask pointed to by mask_p
(usually obtained by a call to getaudit(2)). The au_preselect() function
looks up the classes associated with event in audit_event(5) and compares
them with the classes in mask_p. If the classes associated with event
match the classes in the specified portions of the binary preselection
mask pointed to by mask_p, the event is said to be preselected.


The sorf argument indicates whether the comparison is made with the
success portion, the failure portion, or both portions of the mask
pointed to by mask_p.


The following are the valid values of sorf:

AU_PRS_SUCCESS
Compare the event class with the success portion of the
preselection mask.


AU_PRS_FAILURE
Compare the event class with the failure portion of the
preselection mask.


AU_PRS_BOTH
Compare the event class with both the success and
failure portions of the preselection mask.


The flag argument tells au_preselect() how to read the audit_event(5)
database. Upon initial invocation, au_preselect() reads the
audit_event(5) database and allocates space in an internal cache for each
entry with malloc(3C). In subsequent invocations, the value of flag
determines where au_preselect() obtains audit event information. The
following are the valid values of flag:

AU_PRS_REREAD
Get audit event information by searching the
audit_event(5) database.


AU_PRS_USECACHE
Get audit event information from internal cache
created upon the initial invocation. This option is
much faster.


RETURN VALUES


Upon successful completion,au_preselect() returns 0 if event is not
preselected or 1 if event is preselected. If au_preselect() could not
allocate memory or could not find event in the audit_event(5) database,
-1 is returned.

FILES


/etc/security/audit_class
file mapping audit class number to audit
class names and descriptions


/etc/security/audit_event
file mapping audit event number to audit
event names, descriptions and associated
audit classes


ATTRIBUTES


See attributes(7) for a description of the following attributes:


+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|Interface Stability | Stable |
+--------------------+-----------------+
|MT-Level | MT-Safe |
+--------------------+-----------------+

SEE ALSO


getaudit(2), au_open(3BSM), getauclassent(3BSM), getauevent(3BSM),
malloc(3C), audit_class(5), audit_event(5), attributes(7)

NOTES


The au_preselect() function is normally called prior to constructing and
writing an audit record. If the event is not preselected, the overhead of
constructing and writing the record can be saved.


March 6, 2017 AU_PRESELECT(3BSM)