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. 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
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. 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 bdb
suffix dc=example,dc=com
...
overlay accesslog
logdb cn=log
logops writes reads
logold (objectclass=person)
database bdb
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.
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 ) )
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.
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 MUST 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 $ 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
SEE ALSO
slapd.conf(5), slapd-config(5).
ACKNOWLEDGEMENTS
This module was written in 2005 by Howard Chu of Symas Corporation.