ldap(3) — Linux manual page

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | LDAP versions | INPUT and OUTPUT PARAMETERS | DISPLAYING RESULTS | UTILITY ROUTINES | DEPRECATED INTERFACES | BER LIBRARY | INDEX | SEE ALSO | ACKNOWLEDGEMENTS | COLOPHON

LDAP(3)                 Library Functions Manual                 LDAP(3)

NAME         top

       ldap - OpenLDAP Lightweight Directory Access Protocol API

LIBRARY         top

       OpenLDAP LDAP (libldap, -lldap)

SYNOPSIS         top

       #include <ldap.h>

DESCRIPTION         top

       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.

       The OpenLDAP Software package includes a stand-alone server in
       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.

       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.

       The basic interaction is as follows.  A session handle is created
       using ldap_initialize(3) and set the protocol version to 3 by
       calling 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 ldap_start_tls_s(3).  A LDAP bind operation is
       performed by calling 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.,
       ldap_compare_ext_s(3) or ldap_compare_ext(3) followed by
       ldap_result(3)).  Results returned from these routines are
       interpreted by calling the LDAP parsing routines such as
       ldap_parse_result(3).  The LDAP association and underlying
       connection is terminated by calling ldap_unbind_ext(3).  Errors
       can be interpreted by calling ldap_err2string(3).

LDAP versions         top

       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.

       For backwards compatibility reasons, the library defaults to
       version 2.  Hence, all new applications (and all actively
       maintained applications) should use ldap_set_option(3) to select
       version 3.  The library manual pages assume version 3 has been
       selected.

INPUT and OUTPUT PARAMETERS         top

       All character string input/output is expected to be/is UTF-8
       encoded Unicode (version 3.2).

       Distinguished names (DN) (and relative distinguished names (RDN)
       to be passed to the LDAP routines should conform to RFC 4514
       UTF-8 string representation.

       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.

       LDAP URLs to be passed to routines are expected to conform to RFC
       4516 format.  The ldap_url(3) routines can be used to work with
       LDAP URLs.

       LDAP controls to be passed to routines can be manipulated using
       the ldap_controls(3) routines.

DISPLAYING RESULTS         top

       Results obtained from the search routines can be output by hand,
       by calling ldap_first_entry(3) and ldap_next_entry(3) to step
       through the entries returned, ldap_first_attribute(3) and
       ldap_next_attribute(3) to step through an entry's attributes, and
       ldap_get_values(3) to retrieve a given attribute's values.
       Attribute values may or may not be displayable.

UTILITY ROUTINES         top

       Also provided are various utility routines.  The ldap_sort(3)
       routines are used to sort the entries and values returned via the
       ldap search routines.

DEPRECATED INTERFACES         top

       A number of interfaces are now considered deprecated.  For
       instance, ldap_add(3) is deprecated in favor of ldap_add_ext(3).
       Deprecated interfaces generally remain in the library.  The macro
       LDAP_DEPRECATED can be defined to a non-zero value (e.g.,
       -DLDAP_DEPRECATED=1) when compiling program designed to use
       deprecated interfaces.  It is recommended that developers writing
       new programs, or updating old programs, avoid use of deprecated
       interfaces.  Over time, it is expected that documentation (and,
       eventually, support) for deprecated interfaces to be eliminated.

BER LIBRARY         top

       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 lber-decode(3), lber-encode(3), lber-memory(3), and
       lber-types(3).

INDEX         top

       ldap_initialize(3)
              initialize the LDAP library without opening a connection
              to a server

       ldap_result(3)
              wait for the result from an asynchronous operation

       ldap_abandon_ext(3)
              abandon (abort) an asynchronous operation

       ldap_add_ext(3)
              asynchronously add an entry

       ldap_add_ext_s(3)
              synchronously add an entry

       ldap_sasl_bind(3)
              asynchronously bind to the directory

       ldap_sasl_bind_s(3)
              synchronously bind to the directory

       ldap_unbind_ext(3)
              synchronously unbind from the LDAP server and close the
              connection

       ldap_unbind(3) and ldap_unbind_s(3) are
              equivalent to ldap_unbind_ext(3)

       ldap_memfree(3)
              dispose of memory allocated by LDAP routines.

       ldap_compare_ext(3)
              asynchronously compare to a directory entry

       ldap_compare_ext_s(3)
              synchronously compare to a directory entry

       ldap_delete_ext(3)
              asynchronously delete an entry

       ldap_delete_ext_s(3)
              synchronously delete an entry

       ld_errno(3)
              LDAP error indication

       ldap_errlist(3)
              list of LDAP errors and their meanings

       ldap_err2string(3)
              convert LDAP error indication to a string

       ldap_extended_operation(3)
              asynchronously perform an arbitrary extended operation

       ldap_extended_operation_s(3)
              synchronously perform an arbitrary extended operation

       ldap_first_attribute(3)
              return first attribute name in an entry

       ldap_next_attribute(3)
              return next attribute name in an entry

       ldap_first_entry(3)
              return first entry in a chain of search results

       ldap_next_entry(3)
              return next entry in a chain of search results

       ldap_count_entries(3)
              return number of entries in a search result

       ldap_get_dn(3)
              extract the DN from an entry

       ldap_get_values_len(3)
              return an attribute's values with lengths

       ldap_value_free_len(3)
              free memory allocated by ldap_get_values_len(3)

       ldap_count_values_len(3)
              return number of values

       ldap_modify_ext(3)
              asynchronously modify an entry

       ldap_modify_ext_s(3)
              synchronously modify an entry

       ldap_mods_free(3)
              free array of pointers to mod structures used by
              ldap_modify_ext(3)

       ldap_rename(3)
              asynchronously rename an entry

       ldap_rename_s(3)
              synchronously rename an entry

       ldap_msgfree(3)
              free results allocated by ldap_result(3)

       ldap_msgtype(3)
              return the message type of a message from ldap_result(3)

       ldap_msgid(3)
              return the message id of a message from ldap_result(3)

       ldap_search_ext(3)
              asynchronously search the directory

       ldap_search_ext_s(3)
              synchronously search the directory

       ldap_is_ldap_url(3)
              check a URL string to see if it is an LDAP URL

       ldap_url_parse(3)
              break up an LDAP URL string into its components

       ldap_sort_entries(3)
              sort a list of search results

       ldap_sort_values(3)
              sort a list of attribute values

       ldap_sort_strcasecmp(3)
              case insensitive string comparison

SEE ALSO         top

       ldap.conf(5), slapd(8), draft-ietf-ldapext-ldap-c-api-
       xx.txt <http://www.ietf.org>

ACKNOWLEDGEMENTS         top

       OpenLDAP Software is developed and maintained by The OpenLDAP
       Project <http://www.openldap.org/>.  OpenLDAP Software is derived
       from the University of Michigan LDAP 3.3 Release.

       These API manual pages are loosely based upon descriptions
       provided in the IETF/LDAPEXT C LDAP API Internet Draft, a
       (orphaned) work in progress.

COLOPHON         top

       This page is part of the OpenLDAP (an open source implementation
       of the Lightweight Directory Access Protocol) project.
       Information about the project can be found at 
       ⟨http://www.openldap.org/⟩.  If you have a bug report for this
       manual page, see ⟨http://www.openldap.org/its/⟩.  This page was
       obtained from the project's upstream Git repository
       ⟨https://git.openldap.org/openldap/openldap.git⟩ on 2021-04-01.
       (At that time, the date of the most recent commit that was found
       in the repository was 2021-04-01.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there
       is a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to
       man-pages@man7.org

OpenLDAP LDVERSION             RELEASEDATE                       LDAP(3)

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