/etc/security/audit_class is a user-configurable ASCII system file that stores class definitions used in the audit system. Audit events in audit_event(4) are mapped to one or more of the defined audit classes. audit_event can be updated in conjunction with changes to audit_class. See audit_control(4) and audit_user(4) for information about changing the preselection of audit classes in the audit system. Programs can use the getauclassent(3BSM) routines to access audit class information.
The fields for each class entry are separated by colons. Each class entry is a bitmap and is separated from each other by a newline.
Each entry in the audit_class file has the form:
The fields are defined as follows:
Each class is represented as a bit in the class mask which is an unsigned integer. Thus, there are 32 different classes available. Meta-classes can also be defined. These are supersets composed of multiple base classes, and thus will have more than 1 bit in its mask. See EXAMPLES. Two special meta-classes are also pre-defined: all, and no.
Represents a conjunction of all allowed classes, and is provided as a shorthand method of specifying all classes.
Is the invalid class, and any event mapped solely to this class will not be audited. Turning auditing on to the all meta class will not cause events mapped solely to the no class to be written to the audit trail. This class is also used to map obsolete events which are no longer generated. Obsolete events are retained to process old audit trails files.
The following is an example of an audit_class file:
0x00000000:no:invalid class 0x00000001:fr:file read 0x00000002:fw:file write 0x00000004:fa:file attribute access 0x00000008:fm:file attribute modify 0x00000010:fc:file create 0x00000020:fd:file delete 0x00000040:cl:file close 0x00000100:nt:network 0x00000200:ip:ipc 0x00000400:na:non-attribute 0x00001000:lo:login or logout 0x00004000:ap:application 0x000f0000:ad:old administrative (meta-class) 0x00070000:am:administrative (meta-class) 0x00010000:ss:change system state 0x00020000:as:system-wide administration 0x00040000:ua:user administration 0x00080000:aa:audit utilization 0x00300000:pc:process (meta-class) 0x00100000:ps:process start/stop 0x00200000:pm:process modify 0x20000000:io:ioctl 0x40000000:ex:exec 0x80000000:ot:other 0xffffffff:all:all classes (meta-class)
See attributes(5) for descriptions of the following attributes:
The file format stability is evolving. The file content is unstable.
It is possible to deliberately turn on the no class in the kernel, in which case the audit trail will be flooded with records for the audit event AUE_NULL.
This functionality is available only if the Basic Security Module (BSM) has been enabled. See bsmconv(1M) for more information.