xref: /titanic_52/usr/src/lib/krb5/plugins/kdb/ldap/libkdb_ldap/ldap_handle.c (revision 54925bf60766fbb4f1f2d7c843721406a7b7a3fb)
1 #pragma ident	"%Z%%M%	%I%	%E% SMI"
2 
3 /*
4  * lib/kdb/kdb_ldap/ldap_handle.c
5  *
6  * Copyright (c) 2004-2005, Novell, Inc.
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions are met:
11  *
12  *   * Redistributions of source code must retain the above copyright notice,
13  *       this list of conditions and the following disclaimer.
14  *   * Redistributions in binary form must reproduce the above copyright
15  *       notice, this list of conditions and the following disclaimer in the
16  *       documentation and/or other materials provided with the distribution.
17  *   * The copyright holder's name is not used to endorse or promote products
18  *       derived from this software without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
21  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
24  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #include "ldap_main.h"
34 
35 
36 #ifdef ASYNC_BIND
37 
38 /*
39  * Update the server info structure. In case of an asynchronous bind,
40  * this function is called to check the bind status. A flag
41  * server_info_upate_pending is refered before calling this function.
42  * This function sets the server_status to either ON or OFF and
43  * sets the server_info_udpate_pending to OFF.
44  * Do not lock the mutex here. The caller should lock it
45  */
46 
47 static krb5_error_code
48 krb5_update_server_info(ldap_server_handle, server_info)
49     krb5_ldap_server_handle    *ldap_server_handle;
50     krb5_ldap_server_info      *server_info;
51 {
52     krb5_error_code            st=0;
53     struct timeval             ztime={0, 0};
54     LDAPMessage                *result=NULL;
55 
56     if (ldap_server_handle == NULL || server_info == NULL)
57 	return -1;
58 
59     while (st == 0) {
60 	st = ldap_result(ldap_server_handle->ldap_handle, ldap_server_handle->msgid,
61 			 LDAP_MSG_ALL, &ztime, &result);
62 	switch (st) {
63 	case -1:
64 	    server_info->server_status = OFF;
65 	    time(&server_info->downtime);
66 	    break;
67 
68 	case 0:
69 	    continue;
70 	    break;
71 
72 	case LDAP_RES_BIND:
73 	    if ((st=ldap_result2error(ldap_server_handle->ldap_handle, result, 1)) == LDAP_SUCCESS) {
74 		server_info->server_status = ON;
75 	    } else {
76 		/* ?? */	krb5_set_error_message(0, 0, "%s", ldap_err2string(st));
77 		server_info->server_status = OFF;
78 		time(&server_info->downtime);
79 	    }
80 	    ldap_msgfree(result);
81 	    break;
82 	default:
83 	    ldap_msgfree(result);
84 	    continue;
85 	    break;
86 	}
87     }
88     ldap_server_handle->server_info_update_pending = FALSE;
89     return 0;
90 }
91 #endif
92 
93 /*
94  * Return ldap server handle from the pool. If the pool is exhausted return NULL.
95  * Do not lock the mutex, caller should lock it
96  */
97 
98 static krb5_ldap_server_handle *
99 krb5_get_ldap_handle(ldap_context)
100     krb5_ldap_context          *ldap_context;
101 {
102     krb5_ldap_server_handle    *ldap_server_handle=NULL;
103     krb5_ldap_server_info      *ldap_server_info=NULL;
104     int                        cnt=0;
105 
106     while (ldap_context->server_info_list[cnt] != NULL) {
107 	ldap_server_info = ldap_context->server_info_list[cnt];
108 	if (ldap_server_info->server_status != OFF) {
109 	    if (ldap_server_info->ldap_server_handles != NULL) {
110 		ldap_server_handle = ldap_server_info->ldap_server_handles;
111 		ldap_server_info->ldap_server_handles = ldap_server_handle->next;
112 		break;
113 #ifdef ASYNC_BIND
114 		if (ldap_server_handle->server_info_update_pending == TRUE) {
115 		    krb5_update_server_info(context, ldap_server_handle,
116 					    ldap_server_info);
117 		}
118 
119 		if (ldap_server_info->server_status == ON) {
120 		    ldap_server_info->ldap_server_handles = ldap_server_handle->next;
121 		    break;
122 		} else
123 		    ldap_server_handle = NULL;
124 #endif
125 	    }
126 	}
127 	++cnt;
128     }
129     return ldap_server_handle;
130 }
131 
132 /*
133  * This is called incase krb5_get_ldap_handle returns NULL.
134  * Try getting a single connection (handle) and return the same by
135  * calling krb5_get_ldap_handle function.
136  * Do not lock the mutex here. The caller should lock it
137  */
138 
139 static krb5_ldap_server_handle *
140 krb5_retry_get_ldap_handle(ldap_context, st)
141     krb5_ldap_context          *ldap_context;
142     krb5_error_code            *st;
143 {
144     krb5_ldap_server_handle    *ldap_server_handle=NULL;
145 
146     if ((*st=krb5_ldap_db_single_init(ldap_context)) != 0)
147 	return NULL;
148 
149     ldap_server_handle = krb5_get_ldap_handle(ldap_context);
150     return ldap_server_handle;
151 }
152 
153 /*
154  * Put back the ldap server handle to the front of the list of handles of the
155  * ldap server info structure.
156  * Do not lock the mutex here. The caller should lock it.
157  */
158 
159 static krb5_error_code
160 krb5_put_ldap_handle(ldap_server_handle)
161     krb5_ldap_server_handle    *ldap_server_handle;
162 {
163 
164     if (ldap_server_handle == NULL)
165 	return 0;
166 
167     ldap_server_handle->next = ldap_server_handle->server_info->ldap_server_handles;
168     ldap_server_handle->server_info->ldap_server_handles = ldap_server_handle;
169     return 0;
170 }
171 
172 /*
173  * Add a new ldap server handle structure to the server info structure.
174  * This function name can be changed to krb5_insert_ldap_handle.
175  * Do not lock the mutex here. The caller should lock it
176  */
177 
178 krb5_error_code
179 krb5_update_ldap_handle(ldap_server_handle, server_info)
180     krb5_ldap_server_handle    *ldap_server_handle;
181     krb5_ldap_server_info      *server_info;
182 {
183 
184     if (ldap_server_handle == NULL || server_info == NULL)
185 	return 0;
186 
187     ldap_server_handle->next = server_info->ldap_server_handles;
188     server_info->ldap_server_handles = ldap_server_handle;
189     server_info->num_conns++;
190     ldap_server_handle->server_info = server_info;
191     return 0;
192 }
193 
194 /*
195  * Free up all the ldap server handles of the server info.
196  * This function is called when the ldap server returns LDAP_SERVER_DOWN.
197  */
198 
199 static krb5_error_code
200 krb5_ldap_cleanup_handles(ldap_server_info)
201     krb5_ldap_server_info      *ldap_server_info;
202 {
203     krb5_ldap_server_handle    *ldap_server_handle = NULL;
204 
205     while (ldap_server_info->ldap_server_handles != NULL) {
206 	ldap_server_handle = ldap_server_info->ldap_server_handles;
207 	ldap_server_info->ldap_server_handles = ldap_server_handle->next;
208 	/* Solaris kerberos: don't leak ldap handles */
209 	ldap_unbind_s(ldap_server_handle->ldap_handle);
210 	free (ldap_server_handle);
211 	ldap_server_handle = NULL;
212     }
213     return 0;
214 }
215 
216 /*
217  * wrapper function called from outside to get a handle.
218  */
219 
220 krb5_error_code
221 krb5_ldap_request_handle_from_pool(ldap_context, ldap_server_handle)
222     krb5_ldap_context          *ldap_context;
223     krb5_ldap_server_handle    **ldap_server_handle;
224 {
225     krb5_error_code            st=0;
226 
227     *ldap_server_handle = NULL;
228 
229     HNDL_LOCK(ldap_context);
230     if (((*ldap_server_handle)=krb5_get_ldap_handle(ldap_context)) == NULL)
231 	(*ldap_server_handle)=krb5_retry_get_ldap_handle(ldap_context, &st);
232     HNDL_UNLOCK(ldap_context);
233     return st;
234 }
235 
236 /*
237  * wrapper function wrapper called to get the next ldap server handle, when the current
238  * ldap server handle returns LDAP_SERVER_DOWN.
239  */
240 
241 krb5_error_code
242 krb5_ldap_request_next_handle_from_pool(ldap_context, ldap_server_handle)
243     krb5_ldap_context          *ldap_context;
244     krb5_ldap_server_handle    **ldap_server_handle;
245 {
246     krb5_error_code            st=0;
247 
248     HNDL_LOCK(ldap_context);
249     (*ldap_server_handle)->server_info->server_status = OFF;
250     time(&(*ldap_server_handle)->server_info->downtime);
251     krb5_put_ldap_handle(*ldap_server_handle);
252     krb5_ldap_cleanup_handles((*ldap_server_handle)->server_info);
253 
254     if (((*ldap_server_handle)=krb5_get_ldap_handle(ldap_context)) == NULL)
255 	(*ldap_server_handle)=krb5_retry_get_ldap_handle(ldap_context, &st);
256     HNDL_UNLOCK(ldap_context);
257     return st;
258 }
259 
260 /*
261  * wrapper function to call krb5_put_ldap_handle.
262  */
263 
264 void
265 krb5_ldap_put_handle_to_pool(ldap_context, ldap_server_handle)
266     krb5_ldap_context          *ldap_context;
267     krb5_ldap_server_handle    *ldap_server_handle;
268 {
269 
270     if (ldap_server_handle != NULL) {
271 	HNDL_LOCK(ldap_context);
272 	krb5_put_ldap_handle(ldap_server_handle);
273 	HNDL_UNLOCK(ldap_context);
274     }
275     return;
276 }
277 
278