LDAP(3)LDAP(3)NAMEldap - OpenLDAP Lightweight Directory Access Protocol API
LIBRARY
OpenLDAP LDAP (libldap, -lldap)
SYNOPSIS
#include <ldap.h>
DESCRIPTION
The Lightweight Directory Access Protocol provides access
to X.500 directory services. The services may be
stand-alone or part of a distributed directory service.
This API supports LDAP over TCP (RFC2251), LDAP over SSL,
and LDAP over IPC (UNIX domain sockets). This API sup-
ports SASL (RFC2829) and Start TLS (RFC2830). This API is
based upon IETF C LDAP API draft specification, a 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_init(3) or ldap_initialize(3). (The
ldap_initialize(3) routine is preferred, but is not part
of the draft specification.) The underlying session is
established upon first use which is commonly an LDAP bind
operation. The LDAP bind operation is performed by call-
ing ldap_sasl_bind(3) or one of its friends. Next, other
operations are performed by calling one of the synchronous
or asynchronous routines (e.g., ldap_search_ext_s(3) or
ldap_search_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 termi-
nated by calling ldap_unbind_ext(3). Errors can be inter-
preted by calling ldap_err2string(3).
SEARCH FILTERS
Search filters to be passed to the ldap search routines
are to be constructed by hand and should conform to RFC
2254.
DISPLAYING RESULTS
Results obtained from the ldap search routines can be out-
put 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.
CONTROLS
This library supports both LDAP Version 2 and Version 3,
with the Version 2 protocol selected by default. LDAP
Version 3 operations can be extended through the use of
controls. Controls can be sent to a server or returned to
the client with any LDAP message. Extended versions of
the standard routines are available for use with controls.
These routines are generally named by adding _ext to the
regular routine's name.
UNIFORM RESOURCE LOCATORS (URLS)
The ldap_url(3) routines can be used to test a URL to see
if it is an LDAP URL, to parse LDAP URLs into their compo-
nent pieces, and to initiate searches directly using an
LDAP URL.
UTILITY ROUTINES
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.
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 proto-
col elements using the (slightly simplified) Basic Encod-
ing Rules defined by LDAP. They are not normally used
directly by an LDAP application program except in the han-
dling 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).
INDEXldap_open(3) open a connection to an LDAP server
(deprecated, use ldap_init(3))
ldap_init(3) initialize the LDAP library without
opening a connection to a server
ldap_initialize(3) initialize the LDAP library without
opening a connection to a server
ldap_result(3) wait for the result from an asyn-
chronous operation
ldap_abandon(3) abandon (abort) an asynchronous opera-
tion
ldap_add(3) asynchronously add an entry
ldap_add_s(3) synchronously add an entry
ldap_bind(3) asynchronously bind to the directory
ldap_bind_s(3) synchronously bind to the directory
ldap_simple_bind(3) asynchronously bind to the directory
using simple authentication
ldap_simple_bind_s(3)
synchronously bind to the directory
using simple authentication
ldap_unbind(3) synchronously unbind from the LDAP
server and close the connection
ldap_unbind_s(3) equivalent to ldap_unbind(3)
ldap_memfree (3) dispose of memory allocated by LDAP
routines.
ldap_compare(3) asynchronously compare to a directory
entry
ldap_compare_s(3) synchronously compare to a directory
entry
ldap_delete(3) asynchronously delete an entry
ldap_delete_s(3) synchronously delete an entry
ldap_perror(3) print an LDAP error indication to
standard error
ld_errno(3) LDAP error indication
ldap_result2error(3)
extract LDAP error indication from
LDAP result
ldap_errlist(3) list of LDAP errors and their meanings
ldap_err2string(3) convert LDAP error indication to a
string
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_explode_dn(3) convert a DN into its component parts
ldap_explode_rdn(3) convert an RDN into its component
parts
ldap_get_values(3) return an attribute's values
ldap_get_values_len(3)
return an attribute's values with
lengths
ldap_value_free(3) free memory allocated by ldap_get_val-
ues(3)ldap_value_free_len(3)
free memory allocated by ldap_get_val-
ues_len(3)ldap_count_values(3)
return number of values
ldap_count_values_len(3)
return number of values
ldap_modify(3) asynchronously modify an entry
ldap_modify_s(3) synchronously modify an entry
ldap_mods_free(3) free array of pointers to mod struc-
tures used by ldap_modify(3)ldap_modrdn2(3) asynchronously modify the RDN of an
entry
ldap_modrdn2_s(3) synchronously modify the RDN of an
entry
ldap_modrdn(3) deprecated - use ldap_modrdn2(3)ldap_modrdn_s(3) depreciated - use ldap_modrdn2_s(3)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(3) asynchronously search the directory
ldap_search_s(3) synchronously search the directory
ldap_search_st(3) synchronously search the directory
with timeout
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 ALSOldap.conf(5), slapd(8), draft-ietf-ldapext-ldap-c-api-
xx.txt <http://www.ietf.org>
ACKNOWLEDGEMENTS
OpenLDAP is developed and maintained by The OpenLDAP Pro-
ject (http://www.openldap.org/). OpenLDAP is derived from
University of Michigan LDAP 3.3 Release.
These API manual pages are based upon descriptions pro-
vided in the IETF C LDAP API Internet Draft, a work in
progress, edited by Mark Smith.
OpenLDAP LDVERSION RELEASEDATE LDAP(3)