path: root/doc/man/man3/ldap.3

.TH LDAP 3 "RELEASEDATE" "OpenLDAP LDVERSION"
.\" $OpenLDAP$
.\" Copyright 1998-2022 The OpenLDAP Foundation All Rights Reserved.
.\" Copying restrictions apply.  See COPYRIGHT/LICENSE.
.SH NAME
ldap \- OpenLDAP Lightweight Directory Access Protocol API
.SH LIBRARY
OpenLDAP LDAP (libldap, \-lldap)
.SH SYNOPSIS
.nf
.ft B
#include <ldap.h>
.ft
.fi
.SH DESCRIPTION
.LP
The Lightweight Directory Access Protocol (LDAP) (RFC 4510) provides
access to X.500 directory services.  These services may be stand\-alone
or part of a distributed directory service.  This client API supports
LDAP over TCP (RFC 4511), LDAP over TLS/SSL, and LDAP over IPC (UNIX
domain sockets).  This API supports SASL (RFC 4513) and Start TLS
(RFC 4513) as well as a number of protocol extensions.  This API is
loosely based upon IETF/LDAPEXT C LDAP API draft specification, a (orphaned)
work in progress.
.LP
The OpenLDAP Software package includes a stand\-alone server in
.BR slapd (8),
various LDAP clients, and an LDAP client library used to provide
programmatic access to the LDAP protocol. This man page gives an
overview of the LDAP library routines.
.LP
Both synchronous and asynchronous APIs are provided.  Also included are
various routines to parse the results returned from these routines.
These routines are found in the \-lldap library.
.LP
The basic interaction is as follows.  A session handle is
created using
.BR ldap_initialize (3)
and set the protocol version to 3 by calling
.BR ldap_set_option (3).
The underlying session is established first operation is
issued.  This would generally be a Start TLS or Bind operation,
or a Search operation to read attributes of the Root DSE.
A Start TLS operation is performed by calling
.BR ldap_start_tls_s (3).
A LDAP bind operation is performed by calling
.BR ldap_sasl_bind (3)
or one of its friends.
A Search operation is performed by calling ldap_search_ext_s(3)
or one of its friends.

Subsequently, additional operations are performed
by calling one of the synchronous or asynchronous routines (e.g.,
.BR ldap_compare_ext_s (3)
or
.BR ldap_compare_ext (3)
followed by
.BR ldap_result (3)).
Results returned from these routines are interpreted by calling the
LDAP parsing routines such as
.BR ldap_parse_result (3).
The LDAP association and underlying connection is terminated by calling
.BR ldap_unbind_ext (3).
Errors can be interpreted by calling
.BR ldap_err2string (3).
.SH LDAP versions
This library supports version 3 of the Lightweight Directory Access
Protocol (LDAPv3) as defined in RFC 4510.  It also supports a variant
of version 2 of LDAP as defined by U-Mich LDAP and, to some degree,
RFC 1777.  Version 2 (all variants) are considered obsolete.
Version 3 should be used instead.
.LP
For backwards compatibility reasons, the library defaults to version 2.
Hence, all new applications (and all actively maintained applications)
should use
.BR ldap_set_option (3)
to select version 3.  The library manual pages assume version 3
has been selected.
.SH INPUT and OUTPUT PARAMETERS
All character string input/output is expected to be/is UTF-8
encoded Unicode (version 3.2). 
.LP
Distinguished names (DN) (and relative distinguished names (RDN) to
be passed to the LDAP routines should conform to RFC 4514 UTF-8
string representation. 
.LP
Search filters to be passed to the search routines are to be
constructed by hand and should conform to RFC 4515 UTF-8
string representation.
.LP
LDAP URLs to be passed to routines are expected to conform
to RFC 4516 format.  The
.BR ldap_url (3)
routines can be used to work with LDAP URLs.
.LP
LDAP controls to be passed to routines can be manipulated using the
.BR ldap_controls (3)
routines.
.SH DISPLAYING RESULTS
Results obtained from the search routines can be output by hand,
by calling
.BR ldap_first_entry (3)
and
.BR ldap_next_entry (3)
to step through
the entries returned,
.BR ldap_first_attribute (3)
and
.BR ldap_next_attribute (3)
to step through an entry's attributes, and
.BR ldap_get_values (3)
to retrieve a given attribute's values.  Attribute values
may or may not be displayable.
.SH UTILITY ROUTINES
Also provided are various utility routines.  The
.BR ldap_sort (3)
routines are used to sort the entries and values returned via
the ldap search routines. 
.SH DEPRECATED INTERFACES
A number of interfaces are now considered deprecated.  For instance,
ldap_add(3) is deprecated in favor of ldap_add_ext(3).
.so Deprecated
.SH BER LIBRARY
Also included in the distribution is a set of lightweight Basic
Encoding Rules routines.  These routines are used by the LDAP library
routines to encode and decode LDAP protocol elements using the
(slightly simplified) Basic Encoding Rules defined by LDAP.  They are
not normally used directly by an LDAP application program except
in the handling of controls and extended operations.  The
routines provide a printf and scanf\-like interface, as well as
lower\-level access.  These routines are discussed in
.BR lber\-decode (3),
.BR lber\-encode (3),
.BR lber\-memory (3),
and
.BR lber\-types (3).
.SH INDEX
.TP 20
.SM ldap_initialize(3)
initialize the LDAP library without opening a connection to a server
.TP
.SM ldap_result(3)
wait for the result from an asynchronous operation
.TP
.SM ldap_abandon_ext(3)
abandon (abort) an asynchronous operation
.TP
.SM ldap_add_ext(3)
asynchronously add an entry
.TP
.SM ldap_add_ext_s(3)
synchronously add an entry
.TP
.SM ldap_sasl_bind(3)
asynchronously bind to the directory
.TP
.SM ldap_sasl_bind_s(3)
synchronously bind to the directory
.TP
.SM ldap_unbind_ext(3)
synchronously unbind from the LDAP server and close the connection
.TP
.SM ldap_unbind(3) and ldap_unbind_s(3) are
equivalent to
.BR ldap_unbind_ext (3)
.TP
.SM ldap_memfree(3)
dispose of memory allocated by LDAP routines.
.TP
.SM ldap_compare_ext(3)
asynchronously compare to a directory entry
.TP
.SM ldap_compare_ext_s(3)
synchronously compare to a directory entry
.TP
.SM ldap_delete_ext(3)
asynchronously delete an entry
.TP
.SM ldap_delete_ext_s(3)
synchronously delete an entry
.TP
.SM ld_errno(3)
LDAP error indication
.TP
.SM ldap_errlist(3)
list of LDAP errors and their meanings
.TP
.SM ldap_err2string(3)
convert LDAP error indication to a string
.TP
.SM ldap_extended_operation(3)
asynchronously perform an arbitrary extended operation
.TP
.SM ldap_extended_operation_s(3)
synchronously perform an arbitrary extended operation
.TP
.SM ldap_first_attribute(3)
return first attribute name in an entry
.TP
.SM ldap_next_attribute(3)
return next attribute name in an entry
.TP
.SM ldap_first_entry(3)
return first entry in a chain of search results
.TP
.SM ldap_next_entry(3)
return next entry in a chain of search results
.TP
.SM ldap_count_entries(3)
return number of entries in a search result
.TP
.SM ldap_get_dn(3)
extract the DN from an entry
.TP
.SM ldap_get_values_len(3)
return an attribute's values with lengths
.TP
.SM ldap_value_free_len(3)
free memory allocated by ldap_get_values_len(3)
.TP
.SM ldap_count_values_len(3)
return number of values
.TP
.SM ldap_modify_ext(3)
asynchronously modify an entry
.TP
.SM ldap_modify_ext_s(3)
synchronously modify an entry
.TP
.SM ldap_mods_free(3)
free array of pointers to mod structures used by ldap_modify_ext(3)
.TP
.SM ldap_rename(3)
asynchronously rename an entry
.TP
.SM ldap_rename_s(3)
synchronously rename an entry
.TP
.SM ldap_msgfree(3)
free results allocated by ldap_result(3)
.TP
.SM ldap_msgtype(3)
return the message type of a message from ldap_result(3)
.TP
.SM ldap_msgid(3)
return the message id of a message from ldap_result(3)
.TP
.SM ldap_search_ext(3)
asynchronously search the directory
.TP
.SM ldap_search_ext_s(3)
synchronously search the directory
.TP
.SM ldap_is_ldap_url(3)
check a URL string to see if it is an LDAP URL
.TP
.SM ldap_url_parse(3)
break up an LDAP URL string into its components
.TP
.SM ldap_sort_entries(3)
sort a list of search results
.TP
.SM ldap_sort_values(3)
sort a list of attribute values
.TP
.SM ldap_sort_strcasecmp(3)
case insensitive string comparison
.SH SEE ALSO
.BR ldap.conf (5),
.BR slapd (8),
.BR draft-ietf-ldapext-ldap-c-api-xx.txt \ <http://www.ietf.org>
.SH ACKNOWLEDGEMENTS
.so ../Project
.LP
These API manual pages are loosely based upon descriptions provided
in the IETF/LDAPEXT C LDAP API Internet Draft, a (orphaned) work
in progress.