ldap_bind(3LDAP) LDAP Library Functions ldap_bind(3LDAP)NAME
ldap_bind, ldap_bind_s, ldap_sasl_bind, ldap_sasl_bind_s, ldap_sim‐
ple_bind, ldap_simple_bind_s, ldap_unbind, ldap_unbind_s,
ldap_unbind_ext, ldap_set_rebind_proc, ldap_sasl_interactive_bind_s -
LDAP bind functions
SYNOPSIS
cc [ flag... ] file... -lldap [ library... ]
#include <lber.h>
#include <ldap.h>
int ldap_bind(LDAP *ld, char *who, char *cred, int method);
int ldap_bind_s(LDAP *ld, char *who, char *cred, int method);
int ldap_simple_bind(LDAP *ld, char *who, char *passwd);
int ldap_simple_bind_s(LDAP *ld, char *who, char *passwd);
int ldap_unbind(LDAP *ld);
int ldap_unbind_s(LDAP *ld);
int ldap_unbind_ext(LDAP *ld, LDAPControl **serverctrls, LDAPControl
**clientctrls);
void ldap_set_rebind_proc(LDAP *ld, int (*rebindproc);
int ldap_sasl_bind(LDAP *ld, char *dn, char *mechanism, struct berval
**serverctrls, LDAPControl **clientctrls, int *msgidp);
int ldap_sasl_bind_s(LDAP *ld, char *dn, char *mechanism, struct berval
*cred, LDAPControl **serverctrls, LDAPControl **clientctrls);
int ldap_sasl_interactive_bind_s(LDAP *ld, char *dn, char *saslMecha‐
nism, LDAPControl **sctrl, LDAPControl **cctrl, LDAPControl **unsigned
flags, LDAP_SASL_INTERACT_PROC *callback, void *defaults);
DESCRIPTION
These functions provide various interfaces to the LDAP bind operation.
After a connection is made to an LDAP server, the ldap_bind() function
returns the message ID of the request initiated. The ldap_bind_s()
function returns an LDAP error code.
Simple Authentication
The simplest form of the bind call is ldap_simple_bind_s(). The func‐
tion takes the DN (Distinguished Name) of the dn parameter and the
userPassword associated with the entry in passwd to return an LDAP
error code. See ldap_error(3LDAP).
The ldap_simple_bind() call is asynchronous. The function takes the
same parameters as ldap_simple_bind_s() but initiates the bind opera‐
tion and returns the message ID of the request sent. The result of the
operation can be obtained by a subsequent call to ldap_result(3LDAP).
General Authentication
The ldap_bind() and ldap_bind_s() functions are used to select the
authentication method at runtime. Both functions take an extra method
parameter to set the authentication method. For simple authentication,
the method parameter is set to LDAP_AUTH_SIMPLE. The ldap_bind() func‐
tion returns the message id of the request initiated. The ldap_bind_s()
function returns an LDAP error code.
SASL Authentication
The ldap_sasl_bind() and ldap_sasl_bind_s() functions are used for gen‐
eral and extensible authentication over LDAP through the use of the
Simple Authentication Security Layer. The routines both take the DN to
bind as the authentication method. A dotted-string representation of
an OID identifies the method, and the berval structure holds the cre‐
dentials. The special constant value LDAP_SASL_SIMPLE ("") can be
passed to request simple authentication. Otherwise, the ldap_sim‐
ple_bind() function or the ldap_simple_bind_s() function can be used.
The ldap_sasl_interactive_bind_s() helper function takes its data and
performs the necessary ldap_sasl_bind() and associated SASL library
authentication sequencing with the LDAP server that uses the provided
connection (ld).
Upon a successful bind, the ldap_sasl_bind() function will, if negoti‐
ated by the SASL interface, install the necessary internal libldap
plumbing to enable SASL integrity and privacy (over the wire encryp‐
tion) with the LDAP server.
The LDAP_SASL_INTERACTIVE option flag is passed to the libldap API
through the flags argument of the API. The flag tells the API to use
the SASL interactive mode and to have the API request SASL authentica‐
tion data through the LDAP_SASL_INTERACTIVE_PROC callback as needed.
The callback provided is in the form:
typedef int (LDAP_SASL_INTERACT_PROC)
(LDAP *ld, unsigned flags, void* defaults, void *interact);
The user-provided SASL callback is passed to the current LDAP connec‐
tion pointer, the current flags field, an optional pointer to user-
defined data, and the list of sasl_interact_t authentication values
requested by libsasl(3LIB) to complete authentication.
The user-defined callback collects and returns the authentication
information in the sasl_interact_t array according to libsasl rules.
The authentication information can include user IDs, passwords, realms,
or other information defined by SASL. The SASL library uses this date
during sequencing to complete authentication.
Unbinding
The ldap_unbind() call is used to unbind from a directory, to terminate
the current association, and to free the resources contained in the ld
structure. Once the function is called, the connection to the LDAP
server is closed and the ld structure is invalid. The ldap_unbind_s()
and ldap_unbind() calls are identical and synchronous in nature.
The ldap_unbind_ext() function is used to unbind from a directory, to
terminate the current association, and to free the resources contained
in the LDAP structure. Unlike ldap_unbind() and ldap_unbind_s(), both
server and client controls can be explicitly included with
ldap_unbind_ext() requests. No server response is made to an unbind
request and responses should not be expected from server controls
included with unbind requests.
Rebinding While Following Referral
The ldap_set_rebind_proc() call is used to set a function called back
to obtain bind credentials. The credentials are used when a new server
is contacted after an LDAP referral. If ldap_set_rebind_proc() is never
called, or if it is called with a NULL rebindproc parameter, an unau‐
thenticated simple LDAP bind is always done when chasing referrals.
The rebindproc() function is declared as shown below:
int rebindproc(LDAP *ld, char **whop, char **credp,
int *methodp, int freeit);
The LDAP library first calls the rebindproc() to obtain the referral
bind credentials. The freeit parameter is zero. The whop, credp, and
methodp parameters should be set as appropriate. If rebindproc()
returns LDAP_SUCCESS, referral processing continues. The rebindproc()
is called a second time with a non-zero freeit value to give the appli‐
cation a chance to free any memory allocated in the previous call.
If anything but LDAP_SUCCESS is returned by the first call to rebind‐
proc(), referral processing is stopped and the error code is returned
for the original LDAP operation.
RETURN VALUES
Make a call to ldap_result(3LDAP) to obtain the result of a bind opera‐
tion.
ERRORS
Asynchronous functions will return −1 in case of error. See
ldap_error(3LDAP) for more information on error codes returned. If no
credentials are returned, the result parameter is set to NULL.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌─────────────────────────────┬─────────────────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├─────────────────────────────┼─────────────────────────────┤
│Interface Stability │Evolving │
├─────────────────────────────┼─────────────────────────────┤
│MT-Level │Safe │
└─────────────────────────────┴─────────────────────────────┘
SEE ALSOldap(3LDAP), ldap_error(3LDAP), ldap_open(3LDAP), ldap_result(3LDAP),
libsasl(3LIB), attributes(5)SunOS 5.10 14 Jan 2004 ldap_bind(3LDAP)