Net::LDAP::Control

Section: User Contributed Perl Documentation (3)
Updated: 2021-02-16
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NAME

Net::LDAP::Control - LDAPv3 control object base class

SYNOPSIS

 use Net::LDAP::Control;
 use Net::LDAP::Constant qw( LDAP_CONTROL_MANAGEDSAIT );

 my $req_ctrl1 = Net::LDAP::Control->new( type => LDAP_CONTROL_MANAGEDSAIT );
 my $req_ctrl2 = Net::LDAP::Control->new(
   type     => "1.2.3.4",
   value    => "help",
   critical => 0
 );

 $mesg = $ldap->search( @args, control => [ $req_ctrl1, $req_ctrl2 ]);

 my @res_ctrls = $mesg->control();

DESCRIPTION

"Net::LDAP::Control" is the base-class for LDAPv3 control objects.

Controls provide a mechanism that allows one to extend the semantics and arguments of LDAP operations. Controls may be attached to LDAP operations, and only affect the semantics of the operation they are attached to.

Controls sent by clients are termed request controls, and are set using the "control" option of the respective LDAP operations. Controls sent by servers are called response controls, they can be found using the "control()" method of the response message objects.

Servers announce the controls they support in the attribute "supportedControls" in their RootDSE.

CONSTRUCTORS

new ( ARGS )

ARGS is a list of name/value pairs, valid arguments are:

critical

A Boolean value, if TRUE and the control is unrecognized by the server or is inappropriate for the requested operation then the server will return an error and the operation will not be performed.

If FALSE and the control is unrecognized by the server or is inappropriate for the requested operation then the server will ignore the control and perform the requested operation as if the control was not given.

If absent, FALSE is assumed.

type

A dotted-decimal representation of an OBJECT IDENTIFIER which uniquely identifies the control. This prevents conflicts between control names.

This may be omitted if the constructor is being called on a sub-class of Net::LDAP::Control which has registered to be associated with an OID. If the constructor is being called on the Net::LDAP::Control package, then this argument must be given. If the given OID has been registered by a package, then the returned object will be of the type registered to handle that OID.

value

Optional information associated with the control. Its format is specific to the particular control.

from_asn ( ASN )

ASN is a HASH reference, normally extracted from a PDU. It will contain a "type" element and optionally "critical" and "value" elements. On return ASN will be blessed into a package. If "type" is a registered OID, then ASN will be blessed into the registered package, if not then ASN will be blessed into Net::LDAP::Control.

This constructor is used internally by Net::LDAP and assumes that HASH passed contains a valid control. It should be used with caution.

METHODS

In addition to the methods listed below, each of the named parameters to "new" is also available as a method. "type" will return the OID of the control object. "value" and "critical" are set/get methods and will return the current value for each attribute if called without arguments, but may also be called with arguments to set new values.

error ()

If there has been an error returns a description of the error, otherwise it will return "undef"

init ()

"init" will be called as the last step in both constructors. What it does will depend on the sub-class. It must always return the object.

register ( OID )

"register" is provided for sub-class implementors. It should be called as a class method on a sub-class of Net::LDAP::Control with the OID that the class will handle. Net::LDAP::Control will remember this class and OID pair and use it in the following situations.

•: "new" is called as a class method on the Net::LDAP::Control package and OID is passed as the type. The returned object will be blessed into the package that registered the OID.
•: "new" is called as a class method on a registered package and the "type" is not specified. The "type" will be set to the OID registered by that package.
•: "from_asn" is called to construct an object from ASN. The returned object will be blessed into the package which was registered to handle the OID in the ASN.

( to_asn )

Returns a structure suitable for passing to Convert::ASN1 for encoding. This method will be called by Net::LDAP when the control is used.

The base class implementation of this method will call the "value" method without arguments to allow a sub-class to encode it's value. Sub-classes should not need to override this method.

valid ()

Returns true if the object is valid and can be encoded. The default implementation for this method is to return TRUE if there is no error, but sub-classes may override that.

AUTHOR

Graham Barr <gbarr@pobox.com>

Please report any bugs, or post any suggestions, to the perl-ldap mailing list <perl-ldap@perl.org>