openldap/doc/man/man3/ldap_bind.3

.TH LDAP_BIND 3 "13 January 2002" "OpenLDAP LDVERSION"
.\" $OpenLDAP$
.\" Copyright 1998-2002 The OpenLDAP Foundation All Rights Reserved.
.\" Copying restrictions apply.  See COPYRIGHT/LICENSE.
.SH NAME
ldap_bind, ldap_bind_s, ldap_simple_bind, ldap_simple_bind_s, ldap_kerberos_bind_s, ldap_kerberos_bind1, ldap_kerberos_bind1_s, ldap_kerberos_bind2, ldap_kerberos_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
.SH SYNOPSIS
.nf
.B #include <ldap.h>
.LP
.BI "int ldap_bind(LDAP *" ld ", const char *" who ", const char *" cred ","
.RS
.BI "int " method ");"
.RE
.LP
.BI "int ldap_bind_s(LDAP *" ld ", const char *" who ", const char *" cred ","
.RS
.BI "int " method ");"
.RE
.LP
.BI "int ldap_simple_bind(LDAP *" ld ", const char *" who ", const char *" passwd ");"
.LP
.BI "int ldap_simple_bind_s(LDAP *" ld ", const char *" who ", const char *" passwd ");"
.LP
.BI "int ldap_kerberos_bind_s(LDAP *" ld ", const char *" who ");"
.LP
.BI "int ldap_kerberos_bind1(LDAP *" ld ", const char *" who ");"
.LP
.BI "int ldap_kerberos_bind1_s(LDAP *" ld ", const char *" who ");"
.LP
.BI "int ldap_kerberos_bind2(LDAP *" ld ", const char *" who ");"
.LP
.BI "int ldap_kerberos_bind2_s(LDAP *" ld ", const char *" who ");"
.LP
.BI "int ldap_sasl_bind(LDAP *" ld ", const char *" dn ", const char *" mechanism ","
.RS
.BI "struct berval *" cred ", LDAPControl *" sctrls "[],"
.BI "LDAPControl *" cctrls "[], int *" msgidp ");"
.RE
.LP
.BI "int ldap_sasl_bind_s(LDAP *" ld ", const char *" dn ", const char *" mechanism ","
.RS
.BI "struct berval *" cred ", LDAPControl *" sctrls "[],"
.BI "LDAPControl *" cctrls "[], struct berval **" servercredp ");"
.RE
.LP
.BI "int ldap_parse_sasl_bind_result(LDAP *" ld ", LDAPMessage *" res ","
.RS
.BI "struct berval **" servercredp ", int " freeit ");"
.RE
.LP
.BI "int ldap_sasl_interactive_bind_s(LDAP *" ld ", const char *" dn ","
.RS
.BI "const char *" mechs ", struct berval *" cred ","
.BI "LDAPControl *" sctrls "[], LDAPControl *" cctrls "[],"
.BI "unsigned " flags ", LDAP_SASL_INTERACT_PROC *" interact ","
.BI "void *" defaults ");"
.RE
.LP
.BI "int ldap_unbind(LDAP *" ld ");"
.LP
.BI "int ldap_unbind_s(LDAP *" ld ");"
.\" .LP
.\" .ft B
.\" void ldap_set_rebind_proc( ld, rebindproc )
.\" .ft
.\" LDAP *ld;
.\" int (*rebindproc)();
.SH DESCRIPTION
.LP
These routines provide various interfaces to the LDAP bind operation.
After an association with an LDAP server is made using
.BR 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.
.LP
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
.B 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 \fIld\fP as their first parameter, as returned from
.BR ldap_init (3).
.LP
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
security systems.
.LP
.SH SIMPLE AUTHENTICATION
The simplest form of the bind call is
.BR ldap_simple_bind_s() .
It takes the DN to bind as in \fIwho\fP, and the userPassword associated
with the entry in \fIpasswd\fP.  It returns an LDAP error indication
(see
.BR ldap_error (3)).
The
.B 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
.BR ldap_result (3).
.SH 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 backward compatibility.
.LP
These routines assume the user already
has obtained a ticket granting ticket.  The routines take \fIwho\fP, the DN
of the entry to bind as.  The
.B ldap_kerberos_bind_s()
routine does both steps of the Kerberos binding process synchronously.  The
.B ldap_kerberos_bind1_s()
and
.B ldap_kerberos_bind2_s()
routines allow synchronous access to the
individual steps, authenticating to the LDAP server and X.500 DSA, respectively.
The
.B ldap_kerberos_bind1()
and
.B ldap_kerberos_bind2()
routines provide equivalent asynchronous access.
.LP
The
.B 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
configuration 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
.B ldap_kerberos_bind1()
routine or its synchronous equivalent may be used when contacting an
OpenLDAP server.
.SH GENERAL AUTHENTICATION
The
.B ldap_bind()
and
.B ldap_bind_s()
routines can be used when the
authentication method to use needs to be selected at runtime.  They
both take an extra \fImethod\fP 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,
Kerberos authentication to the LDAP server, or Kerberos authentication
to the X.500 DSA, respectively.
.B ldap_bind()
returns the message id of the request it initiates.
.B ldap_bind_s()
returns an LDAP error indication.
.SH SASL AUTHENTICATION
Description still under construction...
.SH UNBINDING
The
.B ldap_unbind()
call is used to unbind from the directory,
terminate the current association, and free the resources contained
in the \fIld\fP structure.  Once it is called, the connection to
the LDAP server is closed, and the \fIld\fP structure is invalid.
The
.B ldap_unbind_s()
call is just another name for
.BR ldap_unbind() ;
both of these calls are synchronous in nature.
.\" .SH RE-BINDING WHILE FOLLOWING REFERRALS
.\" The
.\" .B ldap_set_rebind_proc()
.\" call is used to set a routine that will be called back to obtain bind
.\" credentials used when a new server is contacted during the following of
.\" an LDAP referral.  Note that this function is only available when the
.\" LDAP libraries are compiled with LDAP_REFERRALS defined and is only
.\" used when the ld_options field in the LDAP structure has
.\" LDAP_OPT_REFERRALS set (this is the default).  If
.\" .B ldap_set_rebind_proc()
.\" is never called, or if it is called with a NULL \fIrebindproc\fP
.\" parameter, an unauthenticated simple LDAP bind will always be done
.\" when chasing referrals.
.\" .LP
.\" \fIrebindproc\fP should be a function that is declared like this:
.\" .LP
.\" .nf
.\" int rebindproc( LDAP *ld, char **whop, char **credp,
.\" int *methodp, int freeit );
.\" .fi
.\" .LP
.\" The LDAP library will first call the rebindproc to obtain the
.\" referral bind credentials, and the \fIfreeit\fP parameter will be
.\" zero.  The \fIwhop\fP, \fIcredp\fP, and \fImethodp\fP should be
.\" set as appropriate.  If the rebindproc returns LDAP_SUCCESS, referral
.\" processing continues, and the rebindproc will be called a second
.\" time with \fIfreeit\fP non-zero to give your application a chance to
.\" free any memory allocated in the previous call.
.\" .LP
.\" If anything but LDAP_SUCCESS is returned by the first call to
.\" the rebindproc, then referral processing is stopped and that error code
.\" is returned for the original LDAP operation.
.SH ERRORS
Asynchronous routines will return -1 in case of error, setting the
\fIld_errno\fP parameter of the \fIld\fP structure.  Synchronous
routines return whatever \fIld_errno\fP is set to.  See
.BR ldap_error (3)
for more information.
.SH SEE ALSO
.BR ldap(3),
.BR ldap_error(3),
.BR ldap_open(3),
.B RFC 2222
(http://www.ietf.org),
.B Cyrus SASL
(http://asg.web.cmu.edu/sasl/)
.SH ACKNOWLEDGEMENTS
.B	OpenLDAP
is developed and maintained by The OpenLDAP Project (http://www.openldap.org/).
.B	OpenLDAP
is derived from University of Michigan LDAP 3.3 Release.