slapo-retcode — return code overlay to slapd
ETCDIR/slapd.conf
The retcode
overlay to slapd(8) is useful to test
the behavior of clients when server-generated erroneous
and/or unusual responses occur, e.g. error codes, referrals,
excessive response times and so on.
The error responses are generated according to different strategies.
In the first case, all operations targeted at a specific configurable subtree cause the object related to the request DN to be looked up and checked for return code data: a response code, plus an optional textual message, an optional configurable delay, an optional matched DN field, and, when the response code is "referral", a (list of) referral(s).
Well-known response codes from standard track documents
are provided in retcode.conf, which can be
included after instantiating the overlay.
In the second case, objects of classes inherited from the
errAbsObject, like
errObject or
errAuxObject, when
returned as intermediate responses of a search request, are
changed into the response dictated by their content.
A third mode causes objects to be looked up from the
underlying database to discover if their class inherits from
errABsObject; in
that case, their content is used to compute the corresponding
response.
The behavior is disabled by using the manageDSAit control (RFC
3296); in that case, the resulting object, either present in
the directory or dynamically generated by the overlay, or
contained in the request, is handled as usual.
The config directives that are specific to the retcode overlay must be
prefixed by retcode−, to avoid
conflicts with directives specific to the underlying database
or to other stacked overlays. The following specific
directives can be used to configure the retcode overlay:
This directive defines the parent DN where dynamically generated entries reside. If not defined, the suffix of the database is used.
retcode−item <RDN> <errCode> [op=<oplist>] [text=<message>] [ref=<referral>] [sleeptime=<sec>] [matched=<DN>] [unsolicited=<OID>[:<data>]] [flags=[{pre|post}-]disconnect[,...]]
A dynamically generated entry, located below
retcode−parent. TheerrCodeis the number of the response code; it can be in any format supported by strtol(3). The optionaloplistis a list of operations that cause response code generation; if absent, all operations are affected. Thematchedfield is the matched DN that is returned along with the error, while thetextfield is an optional diagnostics message. Thereffield is only allowed for thereferralresponse code. Thesleeptimefield causes slapd(8) to sleep the specified number of seconds before proceeding with the operation. Theunsolicitedfield can be used to cause the return of an RFC 4511 unsolicited response message; ifOIDis not "0", an extended response is generated, with the optionaldataappended. Ifflagscontainsdisconnect, orpre-disconnect, slapd(8) disconnects abruptly, without notice;post-disconnectcauses disconnection right after sending response as appropriate.
Enables exploitation of in-directory stored errAbsObject. May result in a lot of unnecessary overhead.
Defines a sleep time in seconds that is spent before actually handling any operation. If negative, a random time between 0 and the absolute value of the argument is used.
The retcode
overlay utilizes the "return code" schema described herein.
This schema is specifically designed for use with this
overlay and is not intended to be used otherwise. It is also
noted that the schema describe 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 error code:
( 1.3.6.1.4.1.4203.666.11.4.1.1 NAME ( 'errCode' ) DESC 'LDAP error code' EQUALITY integerMatch ORDERING integerOrderingMatch SYNTAX 1.3.6.1.4.1.1466.115.121.1.27 SINGLE-VALUE )
The operations that trigger the response code:
( 1.3.6.1.4.1.4203.666.11.4.1.2 NAME ( 'errOp' ) DESC 'Operations the errObject applies to' EQUALITY caseIgnoreMatch SUBSTR caseIgnoreSubstringsMatch SYNTAX 1.3.6.1.4.1.1466.115.121.1.15 )
The text message:
( 1.3.6.1.4.1.4203.666.11.4.1.3 NAME ( 'errText' ) DESC 'LDAP error textual description' EQUALITY caseIgnoreMatch SUBSTR caseIgnoreSubstringsMatch SYNTAX 1.3.6.1.4.1.1466.115.121.1.15 SINGLE-VALUE )
The sleep time before the response is actually returned to the client:
( 1.3.6.1.4.1.4203.666.11.4.1.4 NAME ( 'errSleepTime' ) DESC 'Time to wait before returning the error' EQUALITY integerMatch SYNTAX 1.3.6.1.4.1.1466.115.121.1.27 SINGLE-VALUE )
The matched DN returned to the client:
( 1.3.6.1.4.1.4203.666.11.4.1.5 NAME ( 'errMatchedDN' ) DESC 'Value to be returned as matched DN' EQUALITY distinguishedNameMatch SYNTAX 1.3.6.1.4.1.1466.115.121.1.12 SINGLE-VALUE )
The OID to be returned as extended response OID in RFC 4511 unsolicited responses ("0" generates a regular response with msgid set to 0):
( 1.3.6.1.4.1.4203.666.11.4.1.6 NAME ( 'errUnsolicitedOID' ) DESC 'OID to be returned within unsolicited response' EQUALITY objectIdentifierMatch SYNTAX 1.3.6.1.4.1.1466.115.121.1.38 SINGLE-VALUE )
The octet string to be returned as extended response data in RFC 4511 unsolicited response:
( 1.3.6.1.4.1.4203.666.11.4.1.7 NAME ( 'errUnsolicitedData' ) DESC 'Data to be returned within unsolicited response' SYNTAX 1.3.6.1.4.1.1466.115.121.1.40 SINGLE-VALUE )
If TRUE, slapd(8) disconnects abruptly without notice; if FALSE, it disconnects after sending response as appropriate:
( 1.3.6.1.4.1.4203.666.11.4.1.8 NAME ( 'errDisconnect' ) DESC 'Disconnect without notice' SYNTAX 1.3.6.1.4.1.1466.115.121.1.7 SINGLE-VALUE )
The abstract class that triggers the overlay:
( 1.3.6.1.4.1.4203.666.11.4.3.0 NAME ( 'errAbsObject' ) SUP top ABSTRACT MUST ( errCode ) MAY ( cn $ description $ errOp $ errText $ errSleepTime $ errMatchedDN ) )
The standalone structural objectclass for specifically created data:
( 1.3.6.1.4.1.4203.666.11.4.3.1 NAME ( 'errObject' ) SUP errAbsObject STRUCTURAL )
The auxiliary objectclass to alter the behavior of existing objects:
( 1.3.6.1.4.1.4203.666.11.4.3.2 NAME ( 'errAuxObject' ) SUP errAbsObject AUXILIARY )
overlay retcode retcode-parent "ou=RetCodes,dc=example,dc=com" include ./retcode.conf # Wait 10 seconds, then return success (0x00) retcode-item "cn=Success after 10 seconds" 0x00 sleeptime=10 # Wait 10 seconds, then return timelimitExceeded (0x03) retcode-item "cn=Timelimit after 10 seconds" 0x03 sleeptime=10