Ubuntu Manpage: slapo-accesslog - Access Logging overlay to slapd

Provided by: slapd_2.5.18+dfsg-0ubuntu0.22.04.2_amd64

NAME

       slapo-accesslog - Access Logging overlay to slapd

SYNOPSIS

       /etc/ldap/slapd.conf

DESCRIPTION

       The  Access Logging overlay can be used to record all accesses to a given backend database
       on another database. This allows all of the activity on a given database  to  be  reviewed
       using  arbitrary  LDAP  queries,  instead  of  just  logging  to  local  flat  text files.
       Configuration options are available for selecting a subset of operation types to log,  and
       to  automatically  prune  older  log  records  from the logging database.  Log records are
       stored with audit schema (see below) to assure their readability whether viewed as LDIF or
       in raw form.

CONFIGURATION

These slapd.conf options apply to the Access Logging overlay. They should appear after
the overlay directive.

logdb <suffix>
Specify the suffix of a database to be used for storing the log records. The
specified database must be defined elsewhere in the configuration and must support
an ordered return of results such as slapd-mdb(5) The access controls on the log
database should prevent general access. The suffix entry of the log database will
be created automatically by this overlay. The log entries will be generated as the
immediate children of the suffix entry.

logops <operations>
Specify which types of operations to log. The valid operation types are abandon,
add, bind, compare, delete, extended, modify, modrdn, search, and unbind. Aliases
for common sets of operations are also available:

writes add, delete, modify, modrdn

reads compare, search

session
abandon, bind, unbind

all all operations

logbase <operations> <baseDN>
Specify a set of operations that will only be logged if they occur under a specific
subtree of the database. The operation types are as above for the logops setting,
and delimited by a '|' character.

logold <filter>
Specify a filter for matching against Deleted and Modified entries. If the entry
matches the filter, the old contents of the entry will be logged along with the
current request.

logoldattr <attr> ...
Specify a list of attributes whose old contents are always logged in Modify and
ModRDN requests that match any of the filters configured in logold. Usually only
the contents of attributes that were actually modified will be logged; by default
no old attributes are logged for ModRDN requests.

logpurge <age> <interval>
Specify the maximum age for log entries to be retained in the database, and how
often to scan the database for old entries. Both the age and interval are specified
as a time span in days, hours, minutes, and seconds. The time format is
[ddd+]hh:mm[:ss] i.e., the days and seconds components are optional but hours and
minutes are required. Except for days, which can be up to 5 digits, each numeric
field must be exactly two digits. For example
logpurge 2+00:00 1+00:00
would specify that the log database should be scanned every day for old entries,
and entries older than two days should be deleted. When using a log database that
supports ordered indexing on generalizedTime attributes, specifying an eq index on
the reqStart attribute will greatly benefit the performance of the purge operation.

logsuccess TRUE | FALSE
If set to TRUE then log records will only be generated for successful requests,
i.e., requests that produce a result code of 0 (LDAP_SUCCESS). If FALSE, log
records are generated for all requests whether they succeed or not. The default is
FALSE.

EXAMPLES

            database mdb
            suffix dc=example,dc=com
            ...
            overlay accesslog
            logdb cn=log
            logops writes reads
            logbase search|compare ou=testing,dc=example,dc=com
            logold (objectclass=person)

            database mdb
            suffix cn=log
            ...
            index reqStart eq
            access to *
              by dn.base="cn=admin,dc=example,dc=com" read

SCHEMA

The accesslog overlay utilizes the "audit" schema described herein. This schema is
specifically designed for accesslog auditing and is not intended to be used otherwise. It
is also noted that the schema described here is a work in progress, and hence subject to
change without notice. The schema is loaded automatically by the overlay.

The schema includes a number of object classes and associated attribute types as described
below.

The root entry of the underlying accesslog database makes use of the auditContainer class
which is as follows:

( 1.3.6.1.4.1.4203.666.11.5.2.0
NAME 'auditContainer'
DESC 'AuditLog container'
SUP top STRUCTURAL
MAY ( cn $ reqStart $ reqEnd ) )

There is a basic auditObject class from which two additional classes, auditReadObject and
auditWriteObject are derived. Object classes for each type of LDAP operation are further
derived from these classes. This object class hierarchy is designed to allow flexible yet
efficient searches of the log based on either a specific operation type's class, or on
more general classifications. The definition of the auditObject class is as follows:

( 1.3.6.1.4.1.4203.666.11.5.2.1
NAME 'auditObject'
DESC 'OpenLDAP request auditing'
SUP top STRUCTURAL
MUST ( reqStart $ reqType $ reqSession )
MAY ( reqDN $ reqAuthzID $ reqControls $ reqRespControls $
reqEnd $ reqResult $ reqMessage $ reqReferral $ reqEntryUUID ) )

Note that all of the OIDs used in the logging schema currently reside under the OpenLDAP
Experimental branch. It is anticipated that they will migrate to a Standard branch in the
future.

An overview of the attributes follows: reqStart and reqEnd provide the start and end time
of the operation, respectively. They use generalizedTime syntax. The reqStart attribute is
also used as the RDN for each log entry.

The reqType attribute is a simple string containing the type of operation being logged,
e.g. add, delete, search, etc. For extended operations, the type also includes the OID of
the extended operation, e.g. extended(1.1.1.1)

The reqSession attribute is an implementation-specific identifier that is common to all
the operations associated with the same LDAP session. Currently this is slapd's internal
connection ID, stored in decimal.

The reqDN attribute is the distinguishedName of the target of the operation. E.g., for a
Bind request, this is the Bind DN. For an Add request, this is the DN of the entry being
added. For a Search request, this is the base DN of the search.

The reqAuthzID attribute is the distinguishedName of the user that performed the
operation. This will usually be the same name as was established at the start of a
session by a Bind request (if any) but may be altered in various circumstances.

The reqControls and reqRespControls attributes carry any controls sent by the client on
the request and returned by the server in the response, respectively. The attribute values
are just uninterpreted octet strings.

The reqResult attribute is the numeric LDAP result code of the operation, indicating
either success or a particular LDAP error code. An error code may be accompanied by a text
error message which will be recorded in the reqMessage attribute.

The reqReferral attribute carries any referrals that were returned with the result of the
request.

The reqEntryUUID attribute records the entryUUID attribute of the entry operated on, for
an Add request, this is the entryUUID of the newly created entry.

Operation-specific classes are defined with additional attributes to carry all of the
relevant parameters associated with the operation:

( 1.3.6.1.4.1.4203.666.11.5.2.4
NAME 'auditAbandon'
DESC 'Abandon operation'
SUP auditObject STRUCTURAL
MUST reqId )

For the Abandon operation the reqId attribute contains the message ID of the request that
was abandoned.

( 1.3.6.1.4.1.4203.666.11.5.2.5
NAME 'auditAdd'
DESC 'Add operation'
SUP auditWriteObject STRUCTURAL
MUST reqMod )

The Add class inherits from the auditWriteObject class. The Add and Modify classes are
very similar. The reqMod attribute carries all of the attributes of the original entry
being added. (Or in the case of a Modify operation, all of the modifications being
performed.) The values are formatted as
attribute:<+|-|=|#> [ value]
Where '+' indicates an Add of a value, '-' for Delete, '=' for Replace, and '#' for
Increment. In an Add operation, all of the reqMod values will have the '+' designator.

( 1.3.6.1.4.1.4203.666.11.5.2.6
NAME 'auditBind'
DESC 'Bind operation'
SUP auditObject STRUCTURAL
MUST ( reqVersion $ reqMethod ) )

The Bind class includes the reqVersion attribute which contains the LDAP protocol version
specified in the Bind as well as the reqMethod attribute which contains the Bind Method
used in the Bind. This will be the string SIMPLE for LDAP Simple Binds or SASL(<mech>) for
SASL Binds. Note that unless configured as a global overlay, only Simple Binds using DNs
that reside in the current database will be logged.

( 1.3.6.1.4.1.4203.666.11.5.2.7
NAME 'auditCompare'
DESC 'Compare operation'
SUP auditObject STRUCTURAL
MUST reqAssertion )

For the Compare operation the reqAssertion attribute carries the Attribute Value Assertion
used in the compare request.

( 1.3.6.1.4.1.4203.666.11.5.2.8
NAME 'auditDelete'
DESC 'Delete operation'
SUP auditWriteObject STRUCTURAL
MAY reqOld )

The Delete operation needs no further parameters. However, the reqOld attribute may
optionally be used to record the contents of the entry prior to its deletion. The values
are formatted as
attribute: value
The reqOld attribute is only populated if the entry being deleted matches the configured
logold filter.

( 1.3.6.1.4.1.4203.666.11.5.2.9
NAME 'auditModify'
DESC 'Modify operation'
SUP auditWriteObject STRUCTURAL
MAY ( reqOld $ reqMod ) )

The Modify operation contains a description of modifications in the reqMod attribute,
which was already described above in the Add operation. It may optionally contain the
previous contents of any modified attributes in the reqOld attribute, using the same
format as described above for the Delete operation. The reqOld attribute is only
populated if the entry being modified matches the configured logold filter.

( 1.3.6.1.4.1.4203.666.11.5.2.10
NAME 'auditModRDN'
DESC 'ModRDN operation'
SUP auditWriteObject STRUCTURAL
MUST ( reqNewRDN $ reqDeleteOldRDN )
MAY ( reqNewSuperior $ reqMod $ reqOld ) )

The ModRDN class uses the reqNewRDN attribute to carry the new RDN of the request. The
reqDeleteOldRDN attribute is a Boolean value showing TRUE if the old RDN was deleted from
the entry, or FALSE if the old RDN was preserved. The reqNewSuperior attribute carries
the DN of the new parent entry if the request specified the new parent. The reqOld
attribute is only populated if the entry being modified matches the configured logold
filter and contains attributes in the logoldattr list.

( 1.3.6.1.4.1.4203.666.11.5.2.11
NAME 'auditSearch'
DESC 'Search operation'
SUP auditReadObject STRUCTURAL
MUST ( reqScope $ reqDerefAliases $ reqAttrsOnly )
MAY ( reqFilter $ reqAttr $ reqEntries $ reqSizeLimit $
reqTimeLimit ) )

For the Search class the reqScope attribute contains the scope of the original search
request, using the values specified for the LDAP URL format. I.e. base, one, sub, or
subord. The reqDerefAliases attribute is one of never, finding, searching, or always,
denoting how aliases will be processed during the search. The reqAttrsOnly attribute is a
Boolean value showing TRUE if only attribute names were requested, or FALSE if attributes
and their values were requested. The reqFilter attribute carries the filter used in the
search request. The reqAttr attribute lists the requested attributes if specific
attributes were requested. The reqEntries attribute is the integer count of how many
entries were returned by this search request. The reqSizeLimit and reqTimeLimit
attributes indicate what limits were requested on the search operation.

( 1.3.6.1.4.1.4203.666.11.5.2.12
NAME 'auditExtended'
DESC 'Extended operation'
SUP auditObject STRUCTURAL
MAY reqData )

The Extended class represents an LDAP Extended Operation. As noted above, the actual OID
of the operation is included in the reqType attribute of the parent class. If any optional
data was provided with the request, it will be contained in the reqData attribute as an
uninterpreted octet string.

NOTES

       The  Access Log implemented by this overlay may be used for a variety of other tasks, e.g.
       as a ChangeLog for  a  replication  mechanism,  as  well  as  for  security/audit  logging
       purposes.

FILES

       /etc/ldap/slapd.conf
              default slapd configuration file

ACKNOWLEDGEMENTS

       This module was written in 2005 by Howard Chu of Symas Corporation.