1LDAP_BIND(3) Library Functions Manual LDAP_BIND(3)
2
6 ldap_bind, ldap_bind_s, ldap_simple_bind, ldap_simple_bind_s,
7 ldap_sasl_bind, ldap_sasl_bind_s, ldap_sasl_interactive_bind_s,
8 ldap_parse_sasl_bind_result, ldap_unbind, ldap_unbind_s,
9 ldap_unbind_ext, ldap_unbind_ext_s, ldap_set_rebind_proc - LDAP bind
10 routines
11
13 OpenLDAP LDAP (libldap, -lldap)
14
16 #include <ldap.h>
17 int ldap_bind(LDAP *ld, const char *who, const char *cred,
19 int method);
20 int ldap_bind_s(LDAP *ld, const char *who, const char *cred,
22 int method);
23 int ldap_simple_bind(LDAP *ld, const char *who, const char *passwd);
25 int ldap_simple_bind_s(LDAP *ld, const char *who, const char *passwd);
27 int ldap_sasl_bind(LDAP *ld, const char *dn, const char *mechanism,
29 struct berval *cred, LDAPControl *sctrls[],
30 LDAPControl *cctrls[], int *msgidp);
31 int ldap_sasl_bind_s(LDAP *ld, const char *dn, const char *mechanism,
33 struct berval *cred, LDAPControl *sctrls[],
34 LDAPControl *cctrls[], struct berval **servercredp);
35 int ldap_parse_sasl_bind_result(LDAP *ld, LDAPMessage *res,
37 struct berval **servercredp, int freeit);
38 int ldap_sasl_interactive_bind_s(LDAP *ld, const char *dn,
40 const char *mechs,
41 LDAPControl *sctrls[], LDAPControl *cctrls[],
42 unsigned flags, LDAP_SASL_INTERACT_PROC *interact,
43 void *defaults);
44 int (LDAP_SASL_INTERACT_PROC)(LDAP *ld, unsigned flags, void *defaults, void *sasl_interact);
46 int ldap_unbind(LDAP *ld);
48 int ldap_unbind_s(LDAP *ld);
50 int ldap_unbind_ext(LDAP *ld, LDAPControl *sctrls[],
52 LDAPControl *cctrls[]);
53 int ldap_unbind_ext_s(LDAP *ld, LDAPControl *sctrls[],
55 LDAPControl *cctrls[]);
56 int ldap_set_rebind_proc (LDAP *ld, LDAP_REBIND_PROC *ldap_proc, void *params);
58 int (LDAP_REBIND_PROC)(LDAP *ld, LDAP_CONST char *url, ber_tag_t request, ber_int_t msgid, void *params);
60
62 These routines provide various interfaces to the LDAP bind operation.
63 After an association with an LDAP server is made using ldap_init(3), an
64 LDAP bind operation should be performed before other operations are
65 attempted over the connection. An LDAP bind is required when using
66 Version 2 of the LDAP protocol; it is optional for Version 3 but is
67 usually needed due to security considerations.
68 There are three types of bind calls, ones providing simple authentica‐
70 tion, ones providing SASL authentication, and general routines capable
71 of doing either simple or SASL authentication.
72 SASL (Simple Authentication and Security Layer) that can negotiate one
74 of many different kinds of authentication. Both synchronous and asyn‐
75 chronous versions of each variant of the bind call are provided. All
76 routines take ld as their first parameter, as returned from
77 ldap_init(3).
78
80 The simplest form of the bind call is ldap_simple_bind_s(). It takes
81 the DN to bind as in who, and the userPassword associated with the
82 entry in passwd. It returns an LDAP error indication (see
83 ldap_error(3)). The ldap_simple_bind() call is asynchronous, taking
84 the same parameters but only initiating the bind operation and return‐
85 ing the message id of the request it sent. The result of the operation
86 can be obtained by a subsequent call to ldap_result(3).
87
89 The ldap_bind() and ldap_bind_s() routines can be used when the authen‐
90 tication method to use needs to be selected at runtime. They both take
91 an extra method parameter selecting the authentication method to use.
92 It should be set to LDAP_AUTH_SIMPLE to select simple authentication.
93 ldap_bind() returns the message id of the request it initiates.
94 ldap_bind_s() returns an LDAP error indication.
95
97 For SASL binds the server always ignores any provided DN, so the dn
98 parameter should always be NULL. ldap_sasl_bind_s() sends a single
99 SASL bind request with the given SASL mechanism and credentials in the
100 cred parameter. The format of the credentials depends on the particular
101 SASL mechanism in use. For mechanisms that provide mutual authentica‐
102 tion the server's credentials will be returned in the servercredp
103 parameter. The routine returns an LDAP error indication (see
104 ldap_error(3)). The ldap_sasl_bind() call is asynchronous, taking the
105 same parameters but only sending the request and returning the message
106 id of the request it sent. The result of the operation can be obtained
107 by a subsequent call to ldap_result(3). The result must be addition‐
108 ally parsed by ldap_parse_sasl_bind_result() to obtain any server cre‐
109 dentials sent from the server.
110 Many SASL mechanisms require multiple message exchanges to perform a
112 complete authentication. Applications should generally use
113 ldap_sasl_interactive_bind_s() rather than calling the basic
114 ldap_sasl_bind() functions directly. The mechs parameter should contain
115 a space-separated list of candidate mechanisms to use. If this parame‐
116 ter is NULL or empty the library will query the supportedSASLMechanisms
117 attribute from the server's rootDSE for the list of SASL mechanisms the
118 server supports. The flags parameter controls the interaction used to
119 retrieve any necessary SASL authentication parameters and should be one
120 of:
121 LDAP_SASL_AUTOMATIC
123 use defaults if available, prompt otherwise
124 LDAP_SASL_INTERACTIVE
126 always prompt
127 LDAP_SASL_QUIET
129 never prompt
130 The interact function uses the provided defaults to handle requests
132 from the SASL library for particular authentication parameters. There
133 is no defined format for the defaults information; it is up to the
134 caller to use whatever format is appropriate for the supplied interact
135 function. The sasl_interact parameter comes from the underlying SASL
136 library. When used with Cyrus SASL this is an array of sasl_interact_t
137 structures. The Cyrus SASL library will prompt for a variety of inputs,
138 including:
139 SASL_CB_GETREALM
141 the realm for the authentication attempt
142 SASL_CB_AUTHNAME
144 the username to authenticate
145 SASL_CB_PASS
147 the password for the provided username
148 SASL_CB_USER
150 the username to use for proxy authorization
151 SASL_CB_NOECHOPROMPT
153 generic prompt for input with input echoing disabled
154 SASL_CB_ECHOPROMPT
156 generic prompt for input with input echoing enabled
157 SASL_CB_LIST_END
159 indicates the end of the array of prompts
160 See the Cyrus SASL documentation for more details.
162
164 The ldap_set_rebind_proc function() sets the process to use for binding
165 when an operation returns a referral. This function is used when an
166 application needs to bind to another server in order to follow a refer‐
167 ral or search continuation reference.
168 The function takes ld, the rebind function, and the params, the arbi‐
170 trary data like state information which the client might need to prop‐
171 erly rebind. The LDAP_OPT_REFERRALS option in the ld must be set to ON
172 for the libraries to use the rebind function. Use the ldap_set_option
173 function to set the value.
174 The rebind function parameters are as follows:
176 The ld parameter must be used by the application when binding to the
178 referred server if the application wants the libraries to follow the
179 referral.
180 The url parameter points to the URL referral string received from the
182 LDAP server. The LDAP application can use the ldap_url_parse(3) func‐
183 tion to parse the string into its components.
184 The request parameter specifies the type of request that generated the
186 referral.
187 The msgid parameter specifies the message ID of the request generating
189 the referral.
190 The params parameter is the same value as passed originally to the
192 ldap_set_rebind_proc() function.
193 The LDAP libraries set all the parameters when they call the rebind
195 function. The application should not attempt to free either the ld or
196 the url structures in the rebind function.
197 The application must supply to the rebind function the required authen‐
199 tication information such as, user name, password, and certificates.
200 The rebind function must use a synchronous bind method.
201
203 The ldap_unbind() call is used to unbind from the directory, terminate
204 the current association, and free the resources contained in the ld
205 structure. Once it is called, the connection to the LDAP server is
206 closed, and the ld structure is invalid. The ldap_unbind_s() call is
207 just another name for ldap_unbind(); both of these calls are synchro‐
208 nous in nature.
209 The ldap_unbind_ext() and ldap_unbind_ext_s() allows the operations to
211 specify controls.
212
214 Asynchronous routines will return -1 in case of error, setting the
215 ld_errno parameter of the ld structure. Synchronous routines return
216 whatever ld_errno is set to. See ldap_error(3) for more information.
217
219 If an anonymous bind is sufficient for the application, the rebind
220 process need not be provided. The LDAP libraries with the
221 LDAP_OPT_REFERRALS option set to ON (default value) will automatically
222 follow referrals using an anonymous bind.
223 If the application needs stronger authentication than an anonymous
225 bind, you need to provide a rebind process for that authentication
226 method. The bind method must be synchronous.
227
229 ldap(3), ldap_error(3), ldap_open(3), ldap_set_option(3),
230 ldap_url_parse(3) RFC 4422 (http://www.rfc-editor.org), Cyrus SASL
231 (http://asg.web.cmu.edu/sasl/)
232
234 OpenLDAP Software is developed and maintained by The OpenLDAP Project
235 <http://www.openldap.org/>. OpenLDAP Software is derived from Univer‐
236 sity of Michigan LDAP 3.3 Release.
237OpenLDAP 2.4.23 2010/06/30 LDAP_BIND(3)