LDAP_BIND(3)LDAP_BIND(3)NAME
ldap_bind, ldap_bind_s, ldap_simple_bind, ldap_sim-
ple_bind_s, ldap_kerberos_bind_s, ldap_kerberos_bind1,
ldap_kerberos_bind1_s, ldap_kerberos_bind2, ldap_ker-
beros_bind2_s, ldap_sasl_bind, ldap_sasl_bind_s,
ldap_sasl_interactive_bind_s, ldap_parse_sasl_bind_result,
ldap_unbind, ldap_unbind_s - LDAP bind routines
LIBRARY
OpenLDAP LDAP (libldap, -lldap)
SYNOPSIS
#include <ldap.h>
int ldap_bind(LDAP *ld, const char *who, const char *cred,
int method);
int ldap_bind_s(LDAP *ld, const char *who, const char *cred,
int method);
int ldap_simple_bind(LDAP *ld, const char *who, const char *passwd);
int ldap_simple_bind_s(LDAP *ld, const char *who, const char *passwd);
int ldap_kerberos_bind_s(LDAP *ld, const char *who);
int ldap_kerberos_bind1(LDAP *ld, const char *who);
int ldap_kerberos_bind1_s(LDAP *ld, const char *who);
int ldap_kerberos_bind2(LDAP *ld, const char *who);
int ldap_kerberos_bind2_s(LDAP *ld, const char *who);
int ldap_sasl_bind(LDAP *ld, const char *dn, const char *mechanism,
struct berval *cred, LDAPControl *sctrls[],
LDAPControl *cctrls[], int *msgidp);
int ldap_sasl_bind_s(LDAP *ld, const char *dn, const char *mechanism,
struct berval *cred, LDAPControl *sctrls[],
LDAPControl *cctrls[], struct berval **servercredp);
int ldap_parse_sasl_bind_result(LDAP *ld, LDAPMessage *res,
struct berval **servercredp, int freeit);
int ldap_sasl_interactive_bind_s(LDAP *ld, const char *dn,
const char *mechs, struct berval *cred,
LDAPControl *sctrls[], LDAPControl *cctrls[],
unsigned flags, LDAP_SASL_INTERACT_PROC *interact,
void *defaults);
int ldap_unbind(LDAP *ld);
int ldap_unbind_s(LDAP *ld);
DESCRIPTION
These routines provide various interfaces to the LDAP bind
operation. After an association with an LDAP server is
made using ldap_init(3), an LDAP bind operation should be
performed before other operations are attempted over the
connection. An LDAP bind is required when using Version 2
of the LDAP protocol; it is optional for Version 3 but is
usually needed due to security considerations.
There are many types of bind calls, providing simple
authentication, Kerberos version 4 authentication, and
general routines to do either one, as well as calls using
SASL (Simple Authentication and Security Layer) that can
negotiate one of many different kinds of authentication.
Both synchronous and asynchronous versions of each variant
of the bind call are provided. All routines take ld as
their first parameter, as returned from ldap_init(3).
Kerberos version 4 has been superseded by Kerberos version
5, and the Kerberos version 4 support is only provided for
backward compatibility. The SASL interfaces should be used
for new applications. SASL provides a general interface
for using Kerberos versions 4 and 5 and many other secu-
rity systems.
SIMPLE AUTHENTICATION
The simplest form of the bind call is ldap_sim-
ple_bind_s(). It takes the DN to bind as in who, and the
userPassword associated with the entry in passwd. It
returns an LDAP error indication (see ldap_error(3)). The
ldap_simple_bind() call is asynchronous, taking the same
parameters but only initiating the bind operation and
returning the message id of the request it sent. The
result of the operation can be obtained by a subsequent
call to ldap_result(3).
KERBEROS AUTHENTICATION
If the LDAP library and LDAP server being contacted have
been compiled with the KERBEROS option defined, Kerberos
version 4 authentication can be performed. As mentioned
above, these Kerberos routines are provided only for back-
ward compatibility.
These routines assume the user already has obtained a
ticket granting ticket. The routines take who, the DN of
the entry to bind as. The ldap_kerberos_bind_s() routine
does both steps of the Kerberos binding process syn-
chronously. The ldap_kerberos_bind1_s() and ldap_ker-
beros_bind2_s() routines allow synchronous access to the
individual steps, authenticating to the LDAP server and
X.500 DSA, respectively. The ldap_kerberos_bind1() and
ldap_kerberos_bind2() routines provide equivalent asyn-
chronous access.
The ldap_kerberos_bind_s() routine is used to perform both
authentication steps when contacting an LDAP server that
is a gateway to an X.500 DSA. This kind of server config-
uration is only supported in the (very old) University of
Michigan LDAP release. The OpenLDAP package no longer
provides this gateway server. The standalone LDAP server
provided in OpenLDAP may still be configured with Kerberos
version 4 support, but it only requires one authentication
step, and will return an error if the second step is
attempted. Therefore, only the ldap_kerberos_bind1() rou-
tine or its synchronous equivalent may be used when con-
tacting an OpenLDAP server.
GENERAL AUTHENTICATION
The ldap_bind() and ldap_bind_s() routines can be used
when the authentication method to use needs to be selected
at runtime. They both take an extra method parameter
selecting the authentication method to use. It should be
set to one of LDAP_AUTH_SIMPLE, LDAP_AUTH_KRBV41, or
LDAP_AUTH_KRBV42, to select simple authentication, Ker-
beros authentication to the LDAP server, or Kerberos
authentication to the X.500 DSA, respectively.
ldap_bind() returns the message id of the request it ini-
tiates. ldap_bind_s() returns an LDAP error indication.
SASL AUTHENTICATION
Description still under construction...
UNBINDING
The ldap_unbind() call is used to unbind from the direc-
tory, terminate the current association, and free the
resources contained in the ld structure. Once it is
called, the connection to the LDAP server is closed, and
the ld structure is invalid. The ldap_unbind_s() call is
just another name for ldap_unbind(); both of these calls
are synchronous in nature.
ERRORS
Asynchronous routines will return -1 in case of error,
setting the ld_errno parameter of the ld structure. Syn-
chronous routines return whatever ld_errno is set to. See
ldap_error(3) for more information.
SEE ALSOldap(3), ldap_error(3), ldap_open(3), RFC 2222
(http://www.ietf.org), Cyrus SASL
(http://asg.web.cmu.edu/sasl/)
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.
OpenLDAP LDVERSION RELEASEDATE LDAP_BIND(3)
