1/* Licensed to the Apache Software Foundation (ASF) under one or more
2 * contributor license agreements.  See the NOTICE file distributed with
3 * this work for additional information regarding copyright ownership.
4 * The ASF licenses this file to You under the Apache License, Version 2.0
5 * (the "License"); you may not use this file except in compliance with
6 * the License.  You may obtain a copy of the License at
7 *
8 *     http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17/**
18 * @file util_ldap.h
19 * @brief Apache LDAP library
20 */
21
22#ifndef UTIL_LDAP_H
23#define UTIL_LDAP_H
24
25/* APR header files */
26#include "apr.h"
27#include "apr_thread_mutex.h"
28#include "apr_thread_rwlock.h"
29#include "apr_tables.h"
30#include "apr_time.h"
31#include "apr_version.h"
32#if APR_MAJOR_VERSION < 2
33/* The LDAP API is currently only present in APR 1.x */
34#include "apr_ldap.h"
35#include "apr_ldap_rebind.h"
36#else
37#define APR_HAS_LDAP 0
38#endif
39
40#if APR_HAS_SHARED_MEMORY
41#include "apr_rmm.h"
42#include "apr_shm.h"
43#endif
44
45/* this whole thing disappears if LDAP is not enabled */
46#if APR_HAS_LDAP
47
48#if defined(LDAP_UNAVAILABLE) || APR_HAS_MICROSOFT_LDAPSDK
49#define AP_LDAP_IS_SERVER_DOWN(s)                ((s) == LDAP_SERVER_DOWN \
50                ||(s) == LDAP_UNAVAILABLE)
51#else
52#define AP_LDAP_IS_SERVER_DOWN(s)                ((s) == LDAP_SERVER_DOWN)
53#endif
54
55/* Apache header files */
56#include "ap_config.h"
57#include "httpd.h"
58#include "http_config.h"
59#include "http_core.h"
60#include "http_log.h"
61#include "http_protocol.h"
62#include "http_request.h"
63#include "apr_optional.h"
64
65/* Create a set of LDAP_DECLARE macros with appropriate export
66 * and import tags for the platform
67 */
68#if !defined(WIN32)
69#define LDAP_DECLARE(type)            type
70#define LDAP_DECLARE_NONSTD(type)     type
71#define LDAP_DECLARE_DATA
72#elif defined(LDAP_DECLARE_STATIC)
73#define LDAP_DECLARE(type)            type __stdcall
74#define LDAP_DECLARE_NONSTD(type)     type
75#define LDAP_DECLARE_DATA
76#elif defined(LDAP_DECLARE_EXPORT)
77#define LDAP_DECLARE(type)            __declspec(dllexport) type __stdcall
78#define LDAP_DECLARE_NONSTD(type)     __declspec(dllexport) type
79#define LDAP_DECLARE_DATA             __declspec(dllexport)
80#else
81#define LDAP_DECLARE(type)            __declspec(dllimport) type __stdcall
82#define LDAP_DECLARE_NONSTD(type)     __declspec(dllimport) type
83#define LDAP_DECLARE_DATA             __declspec(dllimport)
84#endif
85
86#if APR_HAS_MICROSOFT_LDAPSDK
87#define timeval l_timeval
88#endif
89
90#ifdef __cplusplus
91extern "C" {
92#endif
93
94/*
95 * LDAP Connections
96 */
97
98/* Values that the deref member can have */
99typedef enum {
100    never=LDAP_DEREF_NEVER,
101    searching=LDAP_DEREF_SEARCHING,
102    finding=LDAP_DEREF_FINDING,
103    always=LDAP_DEREF_ALWAYS
104} deref_options;
105
106/* Structure representing an LDAP connection */
107typedef struct util_ldap_connection_t {
108    LDAP *ldap;
109    apr_pool_t *pool;                   /* Pool from which this connection is created */
110#if APR_HAS_THREADS
111    apr_thread_mutex_t *lock;           /* Lock to indicate this connection is in use */
112#endif
113
114    const char *host;                   /* Name of the LDAP server (or space separated list) */
115    int port;                           /* Port of the LDAP server */
116    deref_options deref;                /* how to handle alias dereferening */
117
118    const char *binddn;                 /* DN to bind to server (can be NULL) */
119    const char *bindpw;                 /* Password to bind to server (can be NULL) */
120
121    int bound;                          /* Flag to indicate whether this connection is bound yet */
122
123    int secure;                         /* SSL/TLS mode of the connection */
124    apr_array_header_t *client_certs;   /* Client certificates on this connection */
125
126    const char *reason;                 /* Reason for an error failure */
127
128    struct util_ldap_connection_t *next;
129    struct util_ldap_state_t *st;        /* The LDAP vhost config this connection belongs to */
130    int keep;                            /* Will this connection be kept when it's unlocked */
131
132    int ChaseReferrals;                 /* [on|off] (default = AP_LDAP_CHASEREFERRALS_ON)*/
133    int ReferralHopLimit;               /* # of referral hops to follow (default = AP_LDAP_DEFAULT_HOPLIMIT) */
134    apr_time_t freed;                   /* the time this conn was placed back in the pool */
135    apr_pool_t *rebind_pool;            /* frequently cleared pool for rebind data */
136} util_ldap_connection_t;
137
138typedef struct util_ldap_config_t {
139    int ChaseReferrals;
140    int ReferralHopLimit;
141    apr_array_header_t *client_certs;  /* Client certificates */
142} util_ldap_config_t;
143
144/* LDAP cache state information */
145typedef struct util_ldap_state_t {
146    apr_pool_t *pool;           /* pool from which this state is allocated */
147#if APR_HAS_THREADS
148    apr_thread_mutex_t *mutex;          /* mutex lock for the connection list */
149#endif
150    apr_global_mutex_t *util_ldap_cache_lock;
151
152    apr_size_t cache_bytes;     /* Size (in bytes) of shared memory cache */
153    char *cache_file;           /* filename for shm */
154    long search_cache_ttl;      /* TTL for search cache */
155    long search_cache_size;     /* Size (in entries) of search cache */
156    long compare_cache_ttl;     /* TTL for compare cache */
157    long compare_cache_size;    /* Size (in entries) of compare cache */
158
159    struct util_ldap_connection_t *connections;
160    apr_array_header_t *global_certs;  /* Global CA certificates */
161    int   ssl_supported;
162    int   secure;
163    int   secure_set;
164    int   verify_svr_cert;
165
166#if APR_HAS_SHARED_MEMORY
167    apr_shm_t *cache_shm;
168    apr_rmm_t *cache_rmm;
169#endif
170
171    /* cache ald */
172    void *util_ldap_cache;
173
174    long  connectionTimeout;
175    struct timeval *opTimeout;
176
177    int debug_level;                    /* SDK debug level */
178    apr_interval_time_t connection_pool_ttl;
179    int retries;                        /* number of retries for failed bind/search/compare */
180    apr_interval_time_t retry_delay;    /* delay between retries of failed bind/search/compare */
181} util_ldap_state_t;
182
183/* Used to store arrays of attribute labels/values. */
184struct mod_auth_ldap_groupattr_entry_t {
185    char *name;
186};
187
188/**
189 * Open a connection to an LDAP server
190 * @param ldc A structure containing the expanded details of the server
191 *            to connect to. The handle to the LDAP connection is returned
192 *            as ldc->ldap.
193 * @tip This function connects to the LDAP server and binds. It does not
194 *      connect if already connected (ldc->ldap != NULL). Does not bind
195 *      if already bound.
196 * @return If successful LDAP_SUCCESS is returned.
197 * @fn int util_ldap_connection_open(request_rec *r,
198 *                                        util_ldap_connection_t *ldc)
199 */
200APR_DECLARE_OPTIONAL_FN(int,uldap_connection_open,(request_rec *r,
201                                            util_ldap_connection_t *ldc));
202
203/**
204 * Close a connection to an LDAP server
205 * @param ldc A structure containing the expanded details of the server
206 *            that was connected.
207 * @tip This function unbinds from the LDAP server, and clears ldc->ldap.
208 *      It is possible to rebind to this server again using the same ldc
209 *      structure, using apr_ldap_open_connection().
210 * @fn util_ldap_close_connection(util_ldap_connection_t *ldc)
211 */
212APR_DECLARE_OPTIONAL_FN(void,uldap_connection_close,(util_ldap_connection_t *ldc));
213
214/**
215 * Unbind a connection to an LDAP server
216 * @param ldc A structure containing the expanded details of the server
217 *            that was connected.
218 * @tip This function unbinds the LDAP connection, and disconnects from
219 *      the server. It is used during error conditions, to bring the LDAP
220 *      connection back to a known state.
221 * @fn apr_status_t util_ldap_connection_unbind(util_ldap_connection_t *ldc)
222 */
223APR_DECLARE_OPTIONAL_FN(apr_status_t,uldap_connection_unbind,(void *param));
224
225/**
226 * Find a connection in a list of connections
227 * @param r The request record
228 * @param host The hostname to connect to (multiple hosts space separated)
229 * @param port The port to connect to
230 * @param binddn The DN to bind with
231 * @param bindpw The password to bind with
232 * @param deref The dereferencing behavior
233 * @param secure use SSL on the connection
234 * @tip Once a connection is found and returned, a lock will be acquired to
235 *      lock that particular connection, so that another thread does not try and
236 *      use this connection while it is busy. Once you are finished with a connection,
237 *      apr_ldap_connection_close() must be called to release this connection.
238 * @fn util_ldap_connection_t *util_ldap_connection_find(request_rec *r, const char *host, int port,
239 *                                                           const char *binddn, const char *bindpw, deref_options deref,
240 *                                                           int netscapessl, int starttls)
241 */
242APR_DECLARE_OPTIONAL_FN(util_ldap_connection_t *,uldap_connection_find,(request_rec *r, const char *host, int port,
243                                                  const char *binddn, const char *bindpw, deref_options deref,
244                                                  int secure));
245
246/**
247 * Compare two DNs for sameness
248 * @param r The request record
249 * @param ldc The LDAP connection being used.
250 * @param url The URL of the LDAP connection - used for deciding which cache to use.
251 * @param dn The first DN to compare.
252 * @param reqdn The DN to compare the first DN to.
253 * @param compare_dn_on_server Flag to determine whether the DNs should be checked using
254 *                             LDAP calls or with a direct string comparision. A direct
255 *                             string comparison is faster, but not as accurate - false
256 *                             negative comparisons are possible.
257 * @tip Two DNs can be equal and still fail a string comparison. Eg "dc=example,dc=com"
258 *      and "dc=example, dc=com". Use the compare_dn_on_server unless there are serious
259 *      performance issues.
260 * @fn int util_ldap_cache_comparedn(request_rec *r, util_ldap_connection_t *ldc,
261 *                                        const char *url, const char *dn, const char *reqdn,
262 *                                        int compare_dn_on_server)
263 */
264APR_DECLARE_OPTIONAL_FN(int,uldap_cache_comparedn,(request_rec *r, util_ldap_connection_t *ldc,
265                              const char *url, const char *dn, const char *reqdn,
266                              int compare_dn_on_server));
267
268/**
269 * A generic LDAP compare function
270 * @param r The request record
271 * @param ldc The LDAP connection being used.
272 * @param url The URL of the LDAP connection - used for deciding which cache to use.
273 * @param dn The DN of the object in which we do the compare.
274 * @param attrib The attribute within the object we are comparing for.
275 * @param value The value of the attribute we are trying to compare for.
276 * @tip Use this function to determine whether an attribute/value pair exists within an
277 *      object. Typically this would be used to determine LDAP top-level group
278 *      membership.
279 * @fn int util_ldap_cache_compare(request_rec *r, util_ldap_connection_t *ldc,
280 *                                      const char *url, const char *dn, const char *attrib, const char *value)
281 */
282APR_DECLARE_OPTIONAL_FN(int,uldap_cache_compare,(request_rec *r, util_ldap_connection_t *ldc,
283                            const char *url, const char *dn, const char *attrib, const char *value));
284
285/**
286 * An LDAP function that checks if the specified user is a member of a subgroup.
287 * @param r The request record
288 * @param ldc The LDAP connection being used.
289 * @param url The URL of the LDAP connection - used for deciding which cache to use.
290 * @param dn The DN of the object in which we find subgroups to search within.
291 * @param attrib The attribute within group objects that identify users.
292 * @param value The user attribute value we are trying to compare for.
293 * @param subgroupAttrs The attributes within group objects that identify subgroups.
294 *                      Array of strings.
295 * @param subgroupclasses The objectClass values used to identify groups (and
296 *                      subgroups). apr_array_header_t *.
297 * @param cur_subgroup_depth Current recursive depth during subgroup processing.
298 * @param max_subgroup_depth Maximum depth of recursion allowed during subgroup
299 *                           processing.
300 * @tip Use this function to determine whether an attribute/value pair exists within a
301 *      starting group object or one of its nested subgroups. Typically this would be
302 *      used to determine LDAP nested group membership.
303 * @deffunc int util_ldap_cache_check_subgroups(request_rec *r, util_ldap_connection_t
304 *                                      *ldc, const char *url, const char *dn,
305 *                                      const char *attrib, const char value,
306 *                                      char **subgroupAttrs, apr_array_header_t
307 *                                      *subgroupclasses, int cur_subgroup_depth, int
308 *                                      max_subgroup_depth )
309 */
310APR_DECLARE_OPTIONAL_FN(int,uldap_cache_check_subgroups,(request_rec *r, util_ldap_connection_t *ldc,
311                                       const char *url, const char *dn, const char *attrib, const char *value,
312                                       char **subgroupAttrs, apr_array_header_t *subgroupclasses,
313                                       int cur_subgroup_depth, int max_subgroup_depth));
314
315/**
316 * Checks a username/password combination by binding to the LDAP server
317 * @param r The request record
318 * @param ldc The LDAP connection being used.
319 * @param url The URL of the LDAP connection - used for deciding which cache to use.
320 * @param basedn The Base DN to search for the user in.
321 * @param scope LDAP scope of the search.
322 * @param attrs LDAP attributes to return in search.
323 * @param filter The user to search for in the form of an LDAP filter. This filter must return
324 *               exactly one user for the check to be successful.
325 * @param bindpw The user password to bind as.
326 * @param binddn The DN of the user will be returned in this variable.
327 * @param retvals The values corresponding to the attributes requested in the attrs array.
328 * @tip The filter supplied will be searched for. If a single entry is returned, an attempt
329 *      is made to bind as that user. If this bind succeeds, the user is not validated.
330 * @fn int util_ldap_cache_checkuserid(request_rec *r, util_ldap_connection_t *ldc,
331 *                                          char *url, const char *basedn, int scope, char **attrs,
332 *                                          char *filter, char *bindpw, char **binddn, char ***retvals)
333 */
334APR_DECLARE_OPTIONAL_FN(int,uldap_cache_checkuserid,(request_rec *r, util_ldap_connection_t *ldc,
335                              const char *url, const char *basedn, int scope, char **attrs,
336                              const char *filter, const char *bindpw, const char **binddn, const char ***retvals));
337
338/**
339 * Searches for a specified user object in an LDAP directory
340 * @param r The request record
341 * @param ldc The LDAP connection being used.
342 * @param url The URL of the LDAP connection - used for deciding which cache to use.
343 * @param basedn The Base DN to search for the user in.
344 * @param scope LDAP scope of the search.
345 * @param attrs LDAP attributes to return in search.
346 * @param filter The user to search for in the form of an LDAP filter. This filter must return
347 *               exactly one user for the check to be successful.
348 * @param binddn The DN of the user will be returned in this variable.
349 * @param retvals The values corresponding to the attributes requested in the attrs array.
350 * @tip The filter supplied will be searched for. If a single entry is returned, an attempt
351 *      is made to bind as that user. If this bind succeeds, the user is not validated.
352 * @fn int util_ldap_cache_getuserdn(request_rec *r, util_ldap_connection_t *ldc,
353 *                                          char *url, const char *basedn, int scope, char **attrs,
354 *                                          char *filter, char **binddn, char ***retvals)
355 */
356APR_DECLARE_OPTIONAL_FN(int,uldap_cache_getuserdn,(request_rec *r, util_ldap_connection_t *ldc,
357                              const char *url, const char *basedn, int scope, char **attrs,
358                              const char *filter, const char **binddn, const char ***retvals));
359
360/**
361 * Checks if SSL support is available in mod_ldap
362 * @fn int util_ldap_ssl_supported(request_rec *r)
363 */
364APR_DECLARE_OPTIONAL_FN(int,uldap_ssl_supported,(request_rec *r));
365
366/* from apr_ldap_cache.c */
367
368/**
369 * Init the LDAP cache
370 * @param pool The pool to use to initialise the cache
371 * @param reqsize The size of the shared memory segment to request. A size
372 *                of zero requests the max size possible from
373 *                apr_shmem_init()
374 * @fn void util_ldap_cache_init(apr_pool_t *p, util_ldap_state_t *st)
375 * @return The status code returned is the status code of the
376 *         apr_smmem_init() call. Regardless of the status, the cache
377 *         will be set up at least for in-process or in-thread operation.
378 */
379apr_status_t util_ldap_cache_init(apr_pool_t *pool, util_ldap_state_t *st);
380
381/* from apr_ldap_cache_mgr.c */
382
383/**
384 * Display formatted stats for cache
385 * @param The pool to allocate the returned string from
386 * @tip This function returns a string allocated from the provided pool that describes
387 *      various stats about the cache.
388 * @fn char *util_ald_cache_display(apr_pool_t *pool, util_ldap_state_t *st)
389 */
390char *util_ald_cache_display(request_rec *r, util_ldap_state_t *st);
391#ifdef __cplusplus
392}
393#endif
394#endif /* APR_HAS_LDAP */
395#endif /* UTIL_LDAP_H */
396