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[exim.git] / src / src / lookups / ldap.c
CommitLineData
0a49a7a4 1/* $Cambridge: exim/src/src/lookups/ldap.c,v 1.15 2009/11/16 19:50:38 nm4 Exp $ */
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2
3/*************************************************
4* Exim - an Internet mail transport agent *
5*************************************************/
6
0a49a7a4 7/* Copyright (c) University of Cambridge 1995 - 2009 */
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8/* See the file NOTICE for conditions of use and distribution. */
9
10/* Many thanks to Stuart Lynne for contributing the original code for this
11driver. Further contibutions from Michael Haardt, Brian Candler, Barry
12Pederson, Peter Savitch and Christian Kellner. Particular thanks to Brian for
13researching how to handle the different kinds of error. */
14
15
16#include "../exim.h"
17#include "lf_functions.h"
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18
19
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20/* Include LDAP headers. The code below uses some "old" LDAP interfaces that
21are deprecated in OpenLDAP. I don't know their status in other LDAP
22implementations. LDAP_DEPRECATED causes their prototypes to be defined in
23ldap.h. */
24
25#define LDAP_DEPRECATED 1
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26
27#include <lber.h>
28#include <ldap.h>
29
30
31/* Annoyingly, the different LDAP libraries handle errors in different ways,
32and some other things too. There doesn't seem to be an automatic way of
33distinguishing between them. Local/Makefile should contain a setting of
34LDAP_LIB_TYPE, which in turn causes appropriate macros to be defined for the
35different kinds. Those that matter are:
36
37LDAP_LIB_NETSCAPE
38LDAP_LIB_SOLARIS with synonym LDAP_LIB_SOLARIS7
39LDAP_LIB_OPENLDAP2
40
41These others may be defined, but are in fact the default, so are not tested:
42
43LDAP_LIB_UMICHIGAN
44LDAP_LIB_OPENLDAP1
45*/
46
47#if defined(LDAP_LIB_SOLARIS7) && ! defined(LDAP_LIB_SOLARIS)
48#define LDAP_LIB_SOLARIS
49#endif
50
51
52/* Just in case LDAP_NO_LIMIT is not defined by some of these libraries. */
53
54#ifndef LDAP_NO_LIMIT
55#define LDAP_NO_LIMIT 0
56#endif
57
58
59/* Just in case LDAP_DEREF_NEVER is not defined */
60
61#ifndef LDAP_DEREF_NEVER
62#define LDAP_DEREF_NEVER 0
63#endif
64
65
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66/* Four types of LDAP search are implemented */
67
68#define SEARCH_LDAP_MULTIPLE 0 /* Get attributes from multiple entries */
69#define SEARCH_LDAP_SINGLE 1 /* Get attributes from one entry only */
70#define SEARCH_LDAP_DN 2 /* Get just the DN from one entry */
71#define SEARCH_LDAP_AUTH 3 /* Just checking for authentication */
72
73/* In all 4 cases, the DN is left in $ldap_dn (which post-dates the
74SEARCH_LDAP_DN lookup). */
75
76
77/* Structure and anchor for caching connections. */
78
79typedef struct ldap_connection {
80 struct ldap_connection *next;
81 uschar *host;
82 uschar *user;
83 uschar *password;
84 BOOL bound;
85 int port;
86 LDAP *ld;
87} LDAP_CONNECTION;
88
89static LDAP_CONNECTION *ldap_connections = NULL;
90
91
92
93/*************************************************
94* Internal search function *
95*************************************************/
96
97/* This is the function that actually does the work. It is called (indirectly
98via control_ldap_search) from eldap_find(), eldapauth_find(), eldapdn_find(),
99and eldapm_find(), with a difference in the "search_type" argument.
100
101The case of eldapauth_find() is special in that all it does is do
102authentication, returning OK or FAIL as appropriate. This isn't used as a
103lookup. Instead, it is called from expand.c as an expansion condition test.
104
105The DN from a successful lookup is placed in $ldap_dn. This feature postdates
106the provision of the SEARCH_LDAP_DN facility for returning just the DN as the
107data.
108
109Arguments:
110 ldap_url the URL to be looked up
111 server server host name, when URL contains none
112 s_port server port, used when URL contains no name
113 search_type SEARCH_LDAP_MULTIPLE allows values from multiple entries
114 SEARCH_LDAP_SINGLE allows values from one entry only
115 SEARCH_LDAP_DN gets the DN from one entry
116 res set to point at the result (not used for ldapauth)
117 errmsg set to point a message if result is not OK
118 defer_break set TRUE if no more servers to be tried after a DEFER
119 user user name for authentication, or NULL
120 password password for authentication, or NULL
121 sizelimit max number of entries returned, or 0 for no limit
122 timelimit max time to wait, or 0 for no limit
d00328e2 123 tcplimit max time for network activity, e.g. connect, or 0 for OS default
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124 deference the dereference option, which is one of
125 LDAP_DEREF_{NEVER,SEARCHING,FINDING,ALWAYS}
6ec97b1b 126 referrals the referral option, which is LDAP_OPT_ON or LDAP_OPT_OFF
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127
128Returns: OK or FAIL or DEFER
129 FAIL is given only if a lookup was performed successfully, but
130 returned no data.
131*/
132
133static int
134perform_ldap_search(uschar *ldap_url, uschar *server, int s_port, int search_type,
135 uschar **res, uschar **errmsg, BOOL *defer_break, uschar *user, uschar *password,
6ec97b1b 136 int sizelimit, int timelimit, int tcplimit, int dereference, void *referrals)
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137{
138LDAPURLDesc *ludp = NULL;
139LDAPMessage *result = NULL;
140BerElement *ber;
141LDAP_CONNECTION *lcp;
142
143struct timeval timeout;
144struct timeval *timeoutptr = NULL;
145
146uschar *attr;
147uschar **attrp;
148uschar *data = NULL;
149uschar *dn = NULL;
150uschar *host;
151uschar **values;
152uschar **firstval;
153uschar porttext[16];
154
155uschar *error1 = NULL; /* string representation of errcode (static) */
156uschar *error2 = NULL; /* error message from the server */
157uschar *matched = NULL; /* partially matched DN */
158
159int attr_count = 0;
160int error_yield = DEFER;
161int msgid;
d38f8232 162int rc, ldap_rc, ldap_parse_rc;
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163int port;
164int ptr = 0;
165int rescount = 0;
166int size = 0;
167BOOL attribute_found = FALSE;
168BOOL ldapi = FALSE;
169
170DEBUG(D_lookup)
171 debug_printf("perform_ldap_search: ldap%s URL = \"%s\" server=%s port=%d "
172 "sizelimit=%d timelimit=%d tcplimit=%d\n",
173 (search_type == SEARCH_LDAP_MULTIPLE)? "m" :
174 (search_type == SEARCH_LDAP_DN)? "dn" :
175 (search_type == SEARCH_LDAP_AUTH)? "auth" : "",
176 ldap_url, server, s_port, sizelimit, timelimit, tcplimit);
177
178/* Check if LDAP thinks the URL is a valid LDAP URL. We assume that if the LDAP
179library that is in use doesn't recognize, say, "ldapi", it will barf here. */
180
181if (!ldap_is_ldap_url(CS ldap_url))
182 {
183 *errmsg = string_sprintf("ldap_is_ldap_url: not an LDAP url \"%s\"\n",
184 ldap_url);
185 goto RETURN_ERROR_BREAK;
186 }
187
188/* Parse the URL */
189
190if ((rc = ldap_url_parse(CS ldap_url, &ludp)) != 0)
191 {
192 *errmsg = string_sprintf("ldap_url_parse: (error %d) parsing \"%s\"\n", rc,
193 ldap_url);
194 goto RETURN_ERROR_BREAK;
195 }
196
197/* If the host name is empty, take it from the separate argument, if one is
198given. OpenLDAP 2.0.6 sets an unset hostname to "" rather than empty, but
199expects NULL later in ldap_init() to mean "default", annoyingly. In OpenLDAP
2002.0.11 this has changed (it uses NULL). */
201
202if ((ludp->lud_host == NULL || ludp->lud_host[0] == 0) && server != NULL)
203 {
204 host = server;
205 port = s_port;
206 }
207else
208 {
209 host = US ludp->lud_host;
210 if (host != NULL && host[0] == 0) host = NULL;
211 port = ludp->lud_port;
212 }
213
214DEBUG(D_lookup) debug_printf("after ldap_url_parse: host=%s port=%d\n",
215 host, port);
216
217if (port == 0) port = LDAP_PORT; /* Default if none given */
218sprintf(CS porttext, ":%d", port); /* For messages */
219
220/* If the "host name" is actually a path, we are going to connect using a Unix
221socket, regardless of whether "ldapi" was actually specified or not. This means
222that a Unix socket can be declared in eldap_default_servers, and "traditional"
223LDAP queries using just "ldap" can be used ("ldaps" is similarly overridden).
224The path may start with "/" or it may already be escaped as "%2F" if it was
225actually declared that way in eldap_default_servers. (I did it that way the
226first time.) If the host name is not a path, the use of "ldapi" causes an
227error, except in the default case. (But lud_scheme doesn't seem to exist in
228older libraries.) */
229
230if (host != NULL)
231 {
232 if ((host[0] == '/' || Ustrncmp(host, "%2F", 3) == 0))
233 {
234 ldapi = TRUE;
235 porttext[0] = 0; /* Remove port from messages */
236 }
237
238 #if defined LDAP_LIB_OPENLDAP2
239 else if (strncmp(ludp->lud_scheme, "ldapi", 5) == 0)
240 {
241 *errmsg = string_sprintf("ldapi requires an absolute path (\"%s\" given)",
242 host);
243 goto RETURN_ERROR;
244 }
245 #endif
246 }
247
248/* Count the attributes; we need this later to tell us how to format results */
249
250for (attrp = USS ludp->lud_attrs; attrp != NULL && *attrp != NULL; attrp++)
251 attr_count++;
252
253/* See if we can find a cached connection to this host. The port is not
254relevant for ldapi. The host name pointer is set to NULL if no host was given
255(implying the library default), rather than to the empty string. Note that in
256this case, there is no difference between ldap and ldapi. */
257
258for (lcp = ldap_connections; lcp != NULL; lcp = lcp->next)
259 {
260 if ((host == NULL) != (lcp->host == NULL) ||
261 (host != NULL && strcmpic(lcp->host, host) != 0))
262 continue;
263 if (ldapi || port == lcp->port) break;
264 }
265
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266/* Use this network timeout in any requests. */
267
268if (tcplimit > 0)
269 {
270 timeout.tv_sec = tcplimit;
271 timeout.tv_usec = 0;
272 timeoutptr = &timeout;
273 }
274
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275/* If no cached connection found, we must open a connection to the server. If
276the server name is actually an absolute path, we set ldapi=TRUE above. This
277requests connection via a Unix socket. However, as far as I know, only OpenLDAP
278supports the use of sockets, and the use of ldap_initialize(). */
279
280if (lcp == NULL)
281 {
282 LDAP *ld;
283
284
285 /* --------------------------- OpenLDAP ------------------------ */
286
287 /* There seems to be a preference under OpenLDAP for ldap_initialize()
288 instead of ldap_init(), though I have as yet been unable to find
289 documentation that says this. (OpenLDAP documentation is sparse to
290 non-existent). So we handle OpenLDAP differently here. Also, support for
291 ldapi seems to be OpenLDAP-only at present. */
292
293 #ifdef LDAP_LIB_OPENLDAP2
294
295 /* We now need an empty string for the default host. Get some store in which
296 to build a URL for ldap_initialize(). In the ldapi case, it can't be bigger
297 than (9 + 3*Ustrlen(shost)), whereas in the other cases it can't be bigger
298 than the host name + "ldaps:///" plus : and a port number, say 20 + the
299 length of the host name. What we get should accommodate both, easily. */
300
301 uschar *shost = (host == NULL)? US"" : host;
302 uschar *init_url = store_get(20 + 3 * Ustrlen(shost));
303 uschar *init_ptr;
304
305 /* Handle connection via Unix socket ("ldapi"). We build a basic LDAP URI to
306 contain the path name, with slashes escaped as %2F. */
307
308 if (ldapi)
309 {
310 int ch;
311 init_ptr = init_url + 8;
312 Ustrcpy(init_url, "ldapi://");
313 while ((ch = *shost++) != 0)
314 {
315 if (ch == '/')
316 {
317 Ustrncpy(init_ptr, "%2F", 3);
318 init_ptr += 3;
319 }
320 else *init_ptr++ = ch;
321 }
322 *init_ptr = 0;
323 }
324
325 /* This is not an ldapi call. Just build a URI with the protocol type, host
326 name, and port. */
327
328 else
329 {
330 init_ptr = Ustrchr(ldap_url, '/');
331 Ustrncpy(init_url, ldap_url, init_ptr - ldap_url);
332 init_ptr = init_url + (init_ptr - ldap_url);
333 sprintf(CS init_ptr, "//%s:%d/", shost, port);
334 }
335
336 /* Call ldap_initialize() and check the result */
337
338 DEBUG(D_lookup) debug_printf("ldap_initialize with URL %s\n", init_url);
339 rc = ldap_initialize(&ld, CS init_url);
340 if (rc != LDAP_SUCCESS)
341 {
342 *errmsg = string_sprintf("ldap_initialize: (error %d) URL \"%s\"\n",
343 rc, init_url);
344 goto RETURN_ERROR;
345 }
346 store_reset(init_url); /* Might as well save memory when we can */
347
348
349 /* ------------------------- Not OpenLDAP ---------------------- */
350
351 /* For libraries other than OpenLDAP, use ldap_init(). */
352
353 #else /* LDAP_LIB_OPENLDAP2 */
354 ld = ldap_init(CS host, port);
355 #endif /* LDAP_LIB_OPENLDAP2 */
356
357 /* -------------------------------------------------------------- */
358
359
360 /* Handle failure to initialize */
361
362 if (ld == NULL)
363 {
364 *errmsg = string_sprintf("failed to initialize for LDAP server %s%s - %s",
365 host, porttext, strerror(errno));
366 goto RETURN_ERROR;
367 }
368
369 /* Set the TCP connect time limit if available. This is something that is
370 in Netscape SDK v4.1; I don't know about other libraries. */
371
372 #ifdef LDAP_X_OPT_CONNECT_TIMEOUT
7c7ad977
PH
373 if (tcplimit > 0)
374 {
994a09e9 375 int timeout1000 = tcplimit*1000;
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376 ldap_set_option(ld, LDAP_X_OPT_CONNECT_TIMEOUT, (void *)&timeout1000);
377 }
994a09e9
PH
378 else
379 {
380 int notimeout = LDAP_X_IO_TIMEOUT_NO_TIMEOUT;
381 ldap_set_option(ld, LDAP_X_OPT_CONNECT_TIMEOUT, (void *)&notimeout);
382 }
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383 #endif
384
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385 /* Set the TCP connect timeout. This works with OpenLDAP 2.2.14. */
386
387 #ifdef LDAP_OPT_NETWORK_TIMEOUT
388 if (tcplimit > 0)
389 ldap_set_option(ld, LDAP_OPT_NETWORK_TIMEOUT, (void *)timeoutptr);
8e669ac1 390 #endif
7c7ad977 391
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392 /* I could not get TLS to work until I set the version to 3. That version
393 seems to be the default nowadays. The RFC is dated 1997, so I would hope
394 that all the LDAP libraries support it. Therefore, if eldap_version hasn't
395 been set, go for v3 if we can. */
396
397 if (eldap_version < 0)
398 {
399 #ifdef LDAP_VERSION3
400 eldap_version = LDAP_VERSION3;
401 #else
402 eldap_version = 2;
403 #endif
404 }
405
406 #ifdef LDAP_OPT_PROTOCOL_VERSION
407 ldap_set_option(ld, LDAP_OPT_PROTOCOL_VERSION, (void *)&eldap_version);
408 #endif
409
410 DEBUG(D_lookup) debug_printf("initialized for LDAP (v%d) server %s%s\n",
411 eldap_version, host, porttext);
412
413 /* If not using ldapi and TLS is available, set appropriate TLS options: hard
414 for "ldaps" and soft otherwise. */
415
416 #ifdef LDAP_OPT_X_TLS
417 if (!ldapi)
418 {
419 int tls_option;
420 if (strncmp(ludp->lud_scheme, "ldaps", 5) == 0)
421 {
422 tls_option = LDAP_OPT_X_TLS_HARD;
423 DEBUG(D_lookup) debug_printf("LDAP_OPT_X_TLS_HARD set\n");
424 }
425 else
426 {
427 tls_option = LDAP_OPT_X_TLS_TRY;
428 DEBUG(D_lookup) debug_printf("LDAP_OPT_X_TLS_TRY set\n");
429 }
430 ldap_set_option(ld, LDAP_OPT_X_TLS, (void *)&tls_option);
431 }
432 #endif /* LDAP_OPT_X_TLS */
433
434 /* Now add this connection to the chain of cached connections */
435
436 lcp = store_get(sizeof(LDAP_CONNECTION));
437 lcp->host = (host == NULL)? NULL : string_copy(host);
438 lcp->bound = FALSE;
439 lcp->user = NULL;
440 lcp->password = NULL;
441 lcp->port = port;
442 lcp->ld = ld;
443 lcp->next = ldap_connections;
444 ldap_connections = lcp;
445 }
446
447/* Found cached connection */
448
449else
450 {
451 DEBUG(D_lookup)
452 debug_printf("re-using cached connection to LDAP server %s%s\n",
453 host, porttext);
454 }
455
456/* Bind with the user/password supplied, or an anonymous bind if these values
457are NULL, unless a cached connection is already bound with the same values. */
458
459if (!lcp->bound ||
460 (lcp->user == NULL && user != NULL) ||
461 (lcp->user != NULL && user == NULL) ||
462 (lcp->user != NULL && user != NULL && Ustrcmp(lcp->user, user) != 0) ||
463 (lcp->password == NULL && password != NULL) ||
464 (lcp->password != NULL && password == NULL) ||
465 (lcp->password != NULL && password != NULL &&
466 Ustrcmp(lcp->password, password) != 0))
467 {
468 DEBUG(D_lookup) debug_printf("%sbinding with user=%s password=%s\n",
469 (lcp->bound)? "re-" : "", user, password);
7c7ad977
PH
470 if ((msgid = ldap_bind(lcp->ld, CS user, CS password, LDAP_AUTH_SIMPLE))
471 == -1)
0756eb3c 472 {
7c7ad977 473 *errmsg = string_sprintf("failed to bind the LDAP connection to server "
d00328e2 474 "%s%s - ldap_bind() returned -1", host, porttext);
7c7ad977
PH
475 goto RETURN_ERROR;
476 }
0756eb3c 477
7c7ad977
PH
478 if ((rc = ldap_result( lcp->ld, msgid, 1, timeoutptr, &result )) <= 0)
479 {
480 *errmsg = string_sprintf("failed to bind the LDAP connection to server "
8e669ac1 481 "%s%s - LDAP error: %s", host, porttext,
7c7ad977
PH
482 rc == -1 ? "result retrieval failed" : "timeout" );
483 result = NULL;
484 goto RETURN_ERROR;
485 }
486
487 rc = ldap_result2error( lcp->ld, result, 0 );
488
489 /* Invalid credentials when just checking credentials returns FAIL. This
490 stops any further servers being tried. */
0756eb3c 491
7c7ad977
PH
492 if (search_type == SEARCH_LDAP_AUTH && rc == LDAP_INVALID_CREDENTIALS)
493 {
494 DEBUG(D_lookup)
495 debug_printf("Invalid credentials: ldapauth returns FAIL\n");
496 error_yield = FAIL;
497 goto RETURN_ERROR_NOMSG;
498 }
0756eb3c 499
7c7ad977
PH
500 /* Otherwise we have a problem that doesn't stop further servers from being
501 tried. */
502
503 if (rc != LDAP_SUCCESS)
504 {
0756eb3c
PH
505 *errmsg = string_sprintf("failed to bind the LDAP connection to server "
506 "%s%s - LDAP error %d: %s", host, porttext, rc, ldap_err2string(rc));
507 goto RETURN_ERROR;
508 }
509
510 /* Successful bind */
511
512 lcp->bound = TRUE;
513 lcp->user = (user == NULL)? NULL : string_copy(user);
514 lcp->password = (password == NULL)? NULL : string_copy(password);
7c7ad977
PH
515
516 ldap_msgfree(result);
517 result = NULL;
0756eb3c
PH
518 }
519
520/* If we are just checking credentials, return OK. */
521
522if (search_type == SEARCH_LDAP_AUTH)
523 {
524 DEBUG(D_lookup) debug_printf("Bind succeeded: ldapauth returns OK\n");
525 goto RETURN_OK;
526 }
527
528/* Before doing the search, set the time and size limits (if given). Here again
529the different implementations of LDAP have chosen to do things differently. */
530
531#if defined(LDAP_OPT_SIZELIMIT)
532ldap_set_option(lcp->ld, LDAP_OPT_SIZELIMIT, (void *)&sizelimit);
533ldap_set_option(lcp->ld, LDAP_OPT_TIMELIMIT, (void *)&timelimit);
534#else
535lcp->ld->ld_sizelimit = sizelimit;
536lcp->ld->ld_timelimit = timelimit;
537#endif
538
539/* Similarly for dereferencing aliases. Don't know if this is possible on
540an LDAP library without LDAP_OPT_DEREF. */
541
542#if defined(LDAP_OPT_DEREF)
543ldap_set_option(lcp->ld, LDAP_OPT_DEREF, (void *)&dereference);
544#endif
545
6ec97b1b
PH
546/* Similarly for the referral setting; should the library follow referrals that
547the LDAP server returns? The conditional is just in case someone uses a library
548without it. */
549
550#if defined(LDAP_OPT_REFERRALS)
551ldap_set_option(lcp->ld, LDAP_OPT_REFERRALS, referrals);
552#endif
553
0756eb3c
PH
554/* Start the search on the server. */
555
556DEBUG(D_lookup) debug_printf("Start search\n");
557
558msgid = ldap_search(lcp->ld, ludp->lud_dn, ludp->lud_scope, ludp->lud_filter,
559 ludp->lud_attrs, 0);
560
561if (msgid == -1)
562 {
3ca0ba97
PH
563 #if defined LDAP_LIB_SOLARIS || defined LDAP_LIB_OPENLDAP2
564 int err;
565 ldap_get_option(lcp->ld, LDAP_OPT_ERROR_NUMBER, &err);
8e669ac1 566 *errmsg = string_sprintf("ldap_search failed: %d, %s", err,
3ca0ba97 567 ldap_err2string(err));
8e669ac1
PH
568
569 #else
3ca0ba97
PH
570 *errmsg = string_sprintf("ldap_search failed");
571 #endif
8e669ac1 572
0756eb3c
PH
573 goto RETURN_ERROR;
574 }
575
576/* Loop to pick up results as they come in, setting a timeout if one was
577given. */
578
0756eb3c
PH
579while ((rc = ldap_result(lcp->ld, msgid, 0, timeoutptr, &result)) ==
580 LDAP_RES_SEARCH_ENTRY)
581 {
582 LDAPMessage *e;
583
584 DEBUG(D_lookup) debug_printf("ldap_result loop\n");
585
586 for(e = ldap_first_entry(lcp->ld, result);
587 e != NULL;
588 e = ldap_next_entry(lcp->ld, e))
589 {
590 uschar *new_dn;
591 BOOL insert_space = FALSE;
592
593 DEBUG(D_lookup) debug_printf("LDAP entry loop\n");
594
595 rescount++; /* Count results */
596
597 /* Results for multiple entries values are separated by newlines. */
598
599 if (data != NULL) data = string_cat(data, &size, &ptr, US"\n", 1);
600
601 /* Get the DN from the last result. */
602
603 new_dn = US ldap_get_dn(lcp->ld, e);
604 if (new_dn != NULL)
605 {
606 if (dn != NULL)
607 {
608 #if defined LDAP_LIB_NETSCAPE || defined LDAP_LIB_OPENLDAP2
609 ldap_memfree(dn);
610 #else /* OPENLDAP 1, UMich, Solaris */
611 free(dn);
612 #endif
613 }
614 /* Save for later */
615 dn = new_dn;
616 }
617
618 /* If the data we want is actually the DN rather than any attribute values,
619 (an "ldapdn" search) add it to the data string. If there are multiple
620 entries, the DNs will be concatenated, but we test for this case below, as
621 for SEARCH_LDAP_SINGLE, and give an error. */
622
623 if (search_type == SEARCH_LDAP_DN) /* Do not amalgamate these into one */
624 { /* condition, because of the else */
625 if (new_dn != NULL) /* below, that's for the first only */
626 {
627 data = string_cat(data, &size, &ptr, new_dn, Ustrlen(new_dn));
628 data[ptr] = 0;
629 attribute_found = TRUE;
630 }
631 }
632
633 /* Otherwise, loop through the entry, grabbing attribute values. If there's
634 only one attribute being retrieved, no attribute name is given, and the
635 result is not quoted. Multiple values are separated by (comma, space).
636 If more than one attribute is being retrieved, the data is given as a
637 sequence of name=value pairs, with the value always in quotes. If there are
638 multiple values, they are given within the quotes, comma separated. */
639
640 else for (attr = US ldap_first_attribute(lcp->ld, e, &ber);
641 attr != NULL;
642 attr = US ldap_next_attribute(lcp->ld, e, ber))
643 {
644 if (attr[0] != 0)
645 {
646 /* Get array of values for this attribute. */
647
648 if ((firstval = values = USS ldap_get_values(lcp->ld, e, CS attr))
649 != NULL)
650 {
651 if (attr_count != 1)
652 {
653 if (insert_space)
654 data = string_cat(data, &size, &ptr, US" ", 1);
655 else
656 insert_space = TRUE;
657 data = string_cat(data, &size, &ptr, attr, Ustrlen(attr));
658 data = string_cat(data, &size, &ptr, US"=\"", 2);
659 }
660
661 while (*values != NULL)
662 {
663 uschar *value = *values;
664 int len = Ustrlen(value);
665
666 DEBUG(D_lookup) debug_printf("LDAP attr loop %s:%s\n", attr, value);
667
668 if (values != firstval)
669 data = string_cat(data, &size, &ptr, US", ", 2);
670
671 /* For multiple attributes, the data is in quotes. We must escape
672 internal quotes, backslashes, newlines. */
673
674 if (attr_count != 1)
675 {
676 int j;
677 for (j = 0; j < len; j++)
678 {
679 if (value[j] == '\n')
680 data = string_cat(data, &size, &ptr, US"\\n", 2);
681 else
682 {
683 if (value[j] == '\"' || value[j] == '\\')
684 data = string_cat(data, &size, &ptr, US"\\", 1);
685 data = string_cat(data, &size, &ptr, value+j, 1);
686 }
687 }
688 }
689
690 /* For single attributes, copy the value verbatim */
691
692 else data = string_cat(data, &size, &ptr, value, len);
693
694 /* Move on to the next value */
695
696 values++;
697 attribute_found = TRUE;
698 }
699
700 /* Closing quote at the end of the data for a named attribute. */
701
702 if (attr_count != 1)
703 data = string_cat(data, &size, &ptr, US"\"", 1);
704
705 /* Free the values */
706
707 ldap_value_free(CSS firstval);
708 }
709 }
710
711 #if defined LDAP_LIB_NETSCAPE || defined LDAP_LIB_OPENLDAP2
712
713 /* Netscape and OpenLDAP2 LDAP's attrs are dynamically allocated and need
714 to be freed. UMich LDAP stores them in static storage and does not require
715 this. */
716
717 ldap_memfree(attr);
718 #endif
719 } /* End "for" loop for extracting attributes from an entry */
720 } /* End "for" loop for extracting entries from a result */
721
722 /* Free the result */
723
724 ldap_msgfree(result);
725 result = NULL;
726 } /* End "while" loop for multiple results */
727
728/* Terminate the dynamic string that we have built and reclaim unused store */
729
730if (data != NULL)
731 {
732 data[ptr] = 0;
733 store_reset(data + ptr + 1);
734 }
735
736/* Copy the last dn into eldap_dn */
737
738if (dn != NULL)
739 {
740 eldap_dn = string_copy(dn);
741 #if defined LDAP_LIB_NETSCAPE || defined LDAP_LIB_OPENLDAP2
742 ldap_memfree(dn);
743 #else /* OPENLDAP 1, UMich, Solaris */
744 free(dn);
745 #endif
746 }
747
748DEBUG(D_lookup) debug_printf("search ended by ldap_result yielding %d\n",rc);
749
750if (rc == 0)
751 {
752 *errmsg = US"ldap_result timed out";
753 goto RETURN_ERROR;
754 }
755
756/* A return code of -1 seems to mean "ldap_result failed internally or couldn't
757provide you with a message". Other error states seem to exist where
758ldap_result() didn't give us any message from the server at all, leaving result
759set to NULL. Apparently, "the error parameters of the LDAP session handle will
760be set accordingly". That's the best we can do to retrieve an error status; we
761can't use functions like ldap_result2error because they parse a message from
762the server, which we didn't get.
763
764Annoyingly, the different implementations of LDAP have gone for different
765methods of handling error codes and generating error messages. */
766
767if (rc == -1 || result == NULL)
768 {
769 int err;
770 DEBUG(D_lookup) debug_printf("ldap_result failed\n");
771
772 #if defined LDAP_LIB_SOLARIS || defined LDAP_LIB_OPENLDAP2
773 ldap_get_option(lcp->ld, LDAP_OPT_ERROR_NUMBER, &err);
774 *errmsg = string_sprintf("ldap_result failed: %d, %s",
775 err, ldap_err2string(err));
776
777 #elif defined LDAP_LIB_NETSCAPE
778 /* Dubious (surely 'matched' is spurious here?) */
779 (void)ldap_get_lderrno(lcp->ld, &matched, &error1);
780 *errmsg = string_sprintf("ldap_result failed: %s (%s)", error1, matched);
781
782 #else /* UMich LDAP aka OpenLDAP 1.x */
783 *errmsg = string_sprintf("ldap_result failed: %d, %s",
784 lcp->ld->ld_errno, ldap_err2string(lcp->ld->ld_errno));
785 #endif
786
787 goto RETURN_ERROR;
788 }
789
790/* A return code that isn't -1 doesn't necessarily mean there were no problems
8e669ac1
PH
791with the search. The message must be an LDAP_RES_SEARCH_RESULT or
792LDAP_RES_SEARCH_REFERENCE or else it's something we can't handle. Some versions
793of LDAP do not define LDAP_RES_SEARCH_REFERENCE (LDAP v1 is one, it seems). So
3295e65b
PH
794we don't provide that functionality when we can't. :-) */
795
8e669ac1 796if (rc != LDAP_RES_SEARCH_RESULT
3295e65b
PH
797#ifdef LDAP_RES_SEARCH_REFERENCE
798 && rc != LDAP_RES_SEARCH_REFERENCE
8e669ac1 799#endif
3295e65b 800 )
0756eb3c
PH
801 {
802 *errmsg = string_sprintf("ldap_result returned unexpected code %d", rc);
803 goto RETURN_ERROR;
804 }
805
806/* We have a result message from the server. This doesn't yet mean all is well.
807We need to parse the message to find out exactly what's happened. */
808
d38f8232
PH
809#if defined LDAP_LIB_SOLARIS || defined LDAP_LIB_OPENLDAP2
810 ldap_rc = rc;
8e669ac1 811 ldap_parse_rc = ldap_parse_result(lcp->ld, result, &rc, CSS &matched,
d38f8232
PH
812 CSS &error2, NULL, NULL, 0);
813 DEBUG(D_lookup) debug_printf("ldap_parse_result: %d\n", ldap_parse_rc);
8e669ac1 814 if (ldap_parse_rc < 0 &&
3295e65b 815 (ldap_parse_rc != LDAP_NO_RESULTS_RETURNED
8e669ac1 816 #ifdef LDAP_RES_SEARCH_REFERENCE
3295e65b 817 || ldap_rc != LDAP_RES_SEARCH_REFERENCE
8e669ac1 818 #endif
3295e65b 819 ))
0756eb3c 820 {
d38f8232 821 *errmsg = string_sprintf("ldap_parse_result failed %d", ldap_parse_rc);
0756eb3c
PH
822 goto RETURN_ERROR;
823 }
824 error1 = US ldap_err2string(rc);
825
826#elif defined LDAP_LIB_NETSCAPE
827 /* Dubious (it doesn't reference 'result' at all!) */
828 rc = ldap_get_lderrno(lcp->ld, &matched, &error1);
829
830#else /* UMich LDAP aka OpenLDAP 1.x */
831 rc = ldap_result2error(lcp->ld, result, 0);
832 error1 = ldap_err2string(rc);
833 error2 = lcp->ld->ld_error;
834 matched = lcp->ld->ld_matched;
835#endif
836
837/* Process the status as follows:
838
839 (1) If we get LDAP_SIZELIMIT_EXCEEDED, just carry on, to return the
840 truncated result list.
841
21eb6e72
PH
842 (2) If we get LDAP_RES_SEARCH_REFERENCE, also just carry on. This was a
843 submitted patch that is reported to "do the right thing" with Solaris
844 LDAP libraries. (The problem it addresses apparently does not occur with
845 Open LDAP.)
846
847 (3) The range of errors defined by LDAP_NAME_ERROR generally mean "that
0756eb3c
PH
848 object does not, or cannot, exist in the database". For those cases we
849 fail the lookup.
850
21eb6e72 851 (4) All other non-successes here are treated as some kind of problem with
0756eb3c
PH
852 the lookup, so return DEFER (which is the default in error_yield).
853*/
854
855DEBUG(D_lookup) debug_printf("ldap_parse_result yielded %d: %s\n",
856 rc, ldap_err2string(rc));
857
21eb6e72
PH
858if (rc != LDAP_SUCCESS && rc != LDAP_SIZELIMIT_EXCEEDED
859 #ifdef LDAP_RES_SEARCH_REFERENCE
860 && rc != LDAP_RES_SEARCH_REFERENCE
861 #endif
862 )
0756eb3c
PH
863 {
864 *errmsg = string_sprintf("LDAP search failed - error %d: %s%s%s%s%s",
865 rc,
866 (error1 != NULL)? error1 : US"",
867 (error2 != NULL && error2[0] != 0)? US"/" : US"",
868 (error2 != NULL)? error2 : US"",
869 (matched != NULL && matched[0] != 0)? US"/" : US"",
870 (matched != NULL)? matched : US"");
871
872 #if defined LDAP_NAME_ERROR
873 if (LDAP_NAME_ERROR(rc))
874 #elif defined NAME_ERROR /* OPENLDAP1 calls it this */
875 if (NAME_ERROR(rc))
876 #else
877 if (rc == LDAP_NO_SUCH_OBJECT)
878 #endif
879
880 {
881 DEBUG(D_lookup) debug_printf("lookup failure forced\n");
882 error_yield = FAIL;
883 }
884 goto RETURN_ERROR;
885 }
886
887/* The search succeeded. Check if we have too many results */
888
889if (search_type != SEARCH_LDAP_MULTIPLE && rescount > 1)
890 {
891 *errmsg = string_sprintf("LDAP search: more than one entry (%d) was returned "
892 "(filter not specific enough?)", rescount);
893 goto RETURN_ERROR_BREAK;
894 }
895
896/* Check if we have too few (zero) entries */
897
898if (rescount < 1)
899 {
900 *errmsg = string_sprintf("LDAP search: no results");
901 error_yield = FAIL;
902 goto RETURN_ERROR_BREAK;
903 }
904
905/* If an entry was found, but it had no attributes, we behave as if no entries
906were found, that is, the lookup failed. */
907
908if (!attribute_found)
909 {
910 *errmsg = US"LDAP search: found no attributes";
911 error_yield = FAIL;
912 goto RETURN_ERROR;
913 }
914
915/* Otherwise, it's all worked */
916
917DEBUG(D_lookup) debug_printf("LDAP search: returning: %s\n", data);
918*res = data;
919
920RETURN_OK:
921if (result != NULL) ldap_msgfree(result);
922ldap_free_urldesc(ludp);
923return OK;
924
925/* Error returns */
926
927RETURN_ERROR_BREAK:
928*defer_break = TRUE;
929
930RETURN_ERROR:
931DEBUG(D_lookup) debug_printf("%s\n", *errmsg);
932
933RETURN_ERROR_NOMSG:
934if (result != NULL) ldap_msgfree(result);
935if (ludp != NULL) ldap_free_urldesc(ludp);
936
937#if defined LDAP_LIB_OPENLDAP2
938 if (error2 != NULL) ldap_memfree(error2);
939 if (matched != NULL) ldap_memfree(matched);
940#endif
941
942return error_yield;
943}
944
945
946
947/*************************************************
948* Internal search control function *
949*************************************************/
950
951/* This function is called from eldap_find(), eldapauth_find(), eldapdn_find(),
952and eldapm_find() with a difference in the "search_type" argument. It controls
953calls to perform_ldap_search() which actually does the work. We call that
954repeatedly for certain types of defer in the case when the URL contains no host
955name and eldap_default_servers is set to a list of servers to try. This gives
956more control than just passing over a list of hosts to ldap_open() because it
957handles other kinds of defer as well as just a failure to open. Note that the
958URL is defined to contain either zero or one "hostport" only.
959
960Parameter data in addition to the URL can be passed as preceding text in the
961string, as items of the form XXX=yyy. The URL itself can be detected because it
962must begin "ldapx://", where x is empty, s, or i.
963
964Arguments:
965 ldap_url the URL to be looked up, optionally preceded by other parameter
966 settings
967 search_type SEARCH_LDAP_MULTIPLE allows values from multiple entries
968 SEARCH_LDAP_SINGLE allows values from one entry only
969 SEARCH_LDAP_DN gets the DN from one entry
970 res set to point at the result
971 errmsg set to point a message if result is not OK
972
973Returns: OK or FAIL or DEFER
974*/
975
976static int
977control_ldap_search(uschar *ldap_url, int search_type, uschar **res,
978 uschar **errmsg)
979{
980BOOL defer_break = FALSE;
981int timelimit = LDAP_NO_LIMIT;
982int sizelimit = LDAP_NO_LIMIT;
7c7ad977 983int tcplimit = 0;
0756eb3c 984int sep = 0;
6ec97b1b
PH
985int dereference = LDAP_DEREF_NEVER;
986void* referrals = LDAP_OPT_ON;
0756eb3c
PH
987uschar *url = ldap_url;
988uschar *p;
989uschar *user = NULL;
990uschar *password = NULL;
991uschar *server, *list;
992uschar buffer[512];
993
994while (isspace(*url)) url++;
995
996/* Until the string begins "ldap", search for the other parameter settings that
997are recognized. They are of the form NAME=VALUE, with the value being
998optionally double-quoted. There must still be a space after it, however. No
999NAME has the value "ldap". */
1000
1001while (strncmpic(url, US"ldap", 4) != 0)
1002 {
1003 uschar *name = url;
1004 while (*url != 0 && *url != '=') url++;
1005 if (*url == '=')
1006 {
1007 int namelen;
1008 uschar *value;
1009 namelen = ++url - name;
1010 value = string_dequote(&url);
1011 if (isspace(*url))
1012 {
1013 if (strncmpic(name, US"USER=", namelen) == 0) user = value;
1014 else if (strncmpic(name, US"PASS=", namelen) == 0) password = value;
1015 else if (strncmpic(name, US"SIZE=", namelen) == 0) sizelimit = Uatoi(value);
1016 else if (strncmpic(name, US"TIME=", namelen) == 0) timelimit = Uatoi(value);
7c7ad977
PH
1017 else if (strncmpic(name, US"CONNECT=", namelen) == 0) tcplimit = Uatoi(value);
1018 else if (strncmpic(name, US"NETTIME=", namelen) == 0) tcplimit = Uatoi(value);
0756eb3c
PH
1019
1020 /* Don't know if all LDAP libraries have LDAP_OPT_DEREF */
1021
1022 #ifdef LDAP_OPT_DEREF
1023 else if (strncmpic(name, US"DEREFERENCE=", namelen) == 0)
1024 {
1025 if (strcmpic(value, US"never") == 0) dereference = LDAP_DEREF_NEVER;
1026 else if (strcmpic(value, US"searching") == 0)
1027 dereference = LDAP_DEREF_SEARCHING;
1028 else if (strcmpic(value, US"finding") == 0)
1029 dereference = LDAP_DEREF_FINDING;
1030 if (strcmpic(value, US"always") == 0) dereference = LDAP_DEREF_ALWAYS;
1031 }
1032 #else
1033 else if (strncmpic(name, US"DEREFERENCE=", namelen) == 0)
1034 {
1035 *errmsg = string_sprintf("LDAP_OP_DEREF not defined in this LDAP "
1036 "library - cannot use \"dereference\"");
1037 DEBUG(D_lookup) debug_printf("%s\n", *errmsg);
1038 return DEFER;
1039 }
6ec97b1b 1040 #endif
0756eb3c 1041
6ec97b1b
PH
1042 #ifdef LDAP_OPT_REFERRALS
1043 else if (strncmpic(name, US"REFERRALS=", namelen) == 0)
1044 {
1045 if (strcmpic(value, US"follow") == 0) referrals = LDAP_OPT_ON;
1046 else if (strcmpic(value, US"nofollow") == 0) referrals = LDAP_OPT_OFF;
1047 else
1048 {
1049 *errmsg = string_sprintf("LDAP option REFERRALS is not \"follow\" "
1050 "or \"nofollow\"");
1051 DEBUG(D_lookup) debug_printf("%s\n", *errmsg);
1052 return DEFER;
1053 }
1054 }
1055 #else
1056 else if (strncmpic(name, US"REFERRALS=", namelen) == 0)
1057 {
1058 *errmsg = string_sprintf("LDAP_OP_REFERRALS not defined in this LDAP "
1059 "library - cannot use \"referrals\"");
1060 DEBUG(D_lookup) debug_printf("%s\n", *errmsg);
1061 return DEFER;
1062 }
0756eb3c
PH
1063 #endif
1064
1065 else
1066 {
1067 *errmsg =
1068 string_sprintf("unknown parameter \"%.*s\" precedes LDAP URL",
1069 namelen, name);
1070 DEBUG(D_lookup) debug_printf("LDAP query error: %s\n", *errmsg);
1071 return DEFER;
1072 }
1073 while (isspace(*url)) url++;
1074 continue;
1075 }
1076 }
1077 *errmsg = US"malformed parameter setting precedes LDAP URL";
1078 DEBUG(D_lookup) debug_printf("LDAP query error: %s\n", *errmsg);
1079 return DEFER;
1080 }
1081
1082/* If user is set, de-URL-quote it. Some LDAP libraries do this for themselves,
1083but it seems that not all behave like this. The DN for the user is often the
1084result of ${quote_ldap_dn:...} quoting, which does apply URL quoting, because
1085that is needed when the DN is used as a base DN in a query. Sigh. This is all
1086far too complicated. */
1087
1088if (user != NULL)
1089 {
1090 uschar *s;
1091 uschar *t = user;
1092 for (s = user; *s != 0; s++)
1093 {
1094 int c, d;
1095 if (*s == '%' && isxdigit(c=s[1]) && isxdigit(d=s[2]))
1096 {
1097 c = tolower(c);
1098 d = tolower(d);
1099 *t++ =
1100 (((c >= 'a')? (10 + c - 'a') : c - '0') << 4) |
1101 ((d >= 'a')? (10 + d - 'a') : d - '0');
1102 s += 2;
1103 }
1104 else *t++ = *s;
1105 }
1106 *t = 0;
1107 }
1108
1109DEBUG(D_lookup)
1110 debug_printf("LDAP parameters: user=%s pass=%s size=%d time=%d connect=%d "
6ec97b1b
PH
1111 "dereference=%d referrals=%s\n", user, password, sizelimit, timelimit,
1112 tcplimit, dereference, (referrals == LDAP_OPT_ON)? "on" : "off");
0756eb3c
PH
1113
1114/* If the request is just to check authentication, some credentials must
1115be given. The password must not be empty because LDAP binds with an empty
1116password are considered anonymous, and will succeed on most installations. */
1117
1118if (search_type == SEARCH_LDAP_AUTH)
1119 {
1120 if (user == NULL || password == NULL)
1121 {
1122 *errmsg = US"ldapauth lookups must specify the username and password";
1123 return DEFER;
1124 }
1125 if (password[0] == 0)
1126 {
1127 DEBUG(D_lookup) debug_printf("Empty password: ldapauth returns FAIL\n");
1128 return FAIL;
1129 }
1130 }
1131
1132/* Check for valid ldap url starters */
1133
1134p = url + 4;
1135if (tolower(*p) == 's' || tolower(*p) == 'i') p++;
1136if (Ustrncmp(p, "://", 3) != 0)
1137 {
1138 *errmsg = string_sprintf("LDAP URL does not start with \"ldap://\", "
1139 "\"ldaps://\", or \"ldapi://\" (it starts with \"%.16s...\")", url);
1140 DEBUG(D_lookup) debug_printf("LDAP query error: %s\n", *errmsg);
1141 return DEFER;
1142 }
1143
1144/* No default servers, or URL contains a server name: just one attempt */
1145
1146if (eldap_default_servers == NULL || p[3] != '/')
1147 {
1148 return perform_ldap_search(url, NULL, 0, search_type, res, errmsg,
6ec97b1b
PH
1149 &defer_break, user, password, sizelimit, timelimit, tcplimit, dereference,
1150 referrals);
0756eb3c
PH
1151 }
1152
1153/* Loop through the default servers until OK or FAIL */
1154
1155list = eldap_default_servers;
1156while ((server = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) != NULL)
1157 {
1158 int rc;
1159 int port = 0;
1160 uschar *colon = Ustrchr(server, ':');
1161 if (colon != NULL)
1162 {
1163 *colon = 0;
1164 port = Uatoi(colon+1);
1165 }
1166 rc = perform_ldap_search(url, server, port, search_type, res, errmsg,
6ec97b1b
PH
1167 &defer_break, user, password, sizelimit, timelimit, tcplimit, dereference,
1168 referrals);
0756eb3c
PH
1169 if (rc != DEFER || defer_break) return rc;
1170 }
1171
1172return DEFER;
1173}
1174
1175
1176
1177/*************************************************
1178* Find entry point *
1179*************************************************/
1180
1181/* See local README for interface description. The different kinds of search
1182are handled by a common function, with a flag to differentiate between them.
1183The handle and filename arguments are not used. */
1184
e6d225ae 1185static int
0756eb3c
PH
1186eldap_find(void *handle, uschar *filename, uschar *ldap_url, int length,
1187 uschar **result, uschar **errmsg, BOOL *do_cache)
1188{
1189/* Keep picky compilers happy */
1190do_cache = do_cache;
1191return(control_ldap_search(ldap_url, SEARCH_LDAP_SINGLE, result, errmsg));
1192}
1193
e6d225ae 1194static int
0756eb3c
PH
1195eldapm_find(void *handle, uschar *filename, uschar *ldap_url, int length,
1196 uschar **result, uschar **errmsg, BOOL *do_cache)
1197{
1198/* Keep picky compilers happy */
1199do_cache = do_cache;
1200return(control_ldap_search(ldap_url, SEARCH_LDAP_MULTIPLE, result, errmsg));
1201}
1202
e6d225ae 1203static int
0756eb3c
PH
1204eldapdn_find(void *handle, uschar *filename, uschar *ldap_url, int length,
1205 uschar **result, uschar **errmsg, BOOL *do_cache)
1206{
1207/* Keep picky compilers happy */
1208do_cache = do_cache;
1209return(control_ldap_search(ldap_url, SEARCH_LDAP_DN, result, errmsg));
1210}
1211
1212int
1213eldapauth_find(void *handle, uschar *filename, uschar *ldap_url, int length,
1214 uschar **result, uschar **errmsg, BOOL *do_cache)
1215{
1216/* Keep picky compilers happy */
1217do_cache = do_cache;
1218return(control_ldap_search(ldap_url, SEARCH_LDAP_AUTH, result, errmsg));
1219}
1220
1221
1222
1223/*************************************************
1224* Open entry point *
1225*************************************************/
1226
1227/* See local README for interface description. */
1228
e6d225ae 1229static void *
0756eb3c
PH
1230eldap_open(uschar *filename, uschar **errmsg)
1231{
1232return (void *)(1); /* Just return something non-null */
1233}
1234
1235
1236
1237/*************************************************
1238* Tidy entry point *
1239*************************************************/
1240
1241/* See local README for interface description.
1242Make sure that eldap_dn does not refer to reclaimed or worse, freed store */
1243
e6d225ae 1244static void
0756eb3c
PH
1245eldap_tidy(void)
1246{
1247LDAP_CONNECTION *lcp = NULL;
1248eldap_dn = NULL;
1249
1250while ((lcp = ldap_connections) != NULL)
1251 {
1252 DEBUG(D_lookup) debug_printf("unbind LDAP connection to %s:%d\n", lcp->host,
1253 lcp->port);
1254 ldap_unbind(lcp->ld);
1255 ldap_connections = lcp->next;
1256 }
1257}
1258
1259
1260
1261/*************************************************
1262* Quote entry point *
1263*************************************************/
1264
1265/* LDAP quoting is unbelievably messy. For a start, two different levels of
1266quoting have to be done: LDAP quoting, and URL quoting. The current
1267specification is the result of a suggestion by Brian Candler. It recognizes
1268two separate cases:
1269
1270(1) For text that appears in a search filter, the following escapes are
1271 required (see RFC 2254):
1272
1273 * -> \2A
1274 ( -> \28
1275 ) -> \29
1276 \ -> \5C
1277 NULL -> \00
1278
1279 Then the entire filter text must be URL-escaped. This kind of quoting is
1280 implemented by ${quote_ldap:....}. Note that we can never have a NULL
1281 in the input string, because that's a terminator.
1282
1283(2) For a DN that is part of a URL (i.e. the base DN), the characters
1284
1285 , + " \ < > ;
1286
1287 must be quoted by backslashing. See RFC 2253. Leading and trailing spaces
1288 must be escaped, as must a leading #. Then the string must be URL-quoted.
1289 This type of quoting is implemented by ${quote_ldap_dn:....}.
1290
1291For URL quoting, the only characters that need not be quoted are the
1292alphamerics and
1293
1294 ! $ ' ( ) * + - . _
1295
1296All the others must be hexified and preceded by %. This includes the
1297backslashes used for LDAP quoting.
1298
1299For a DN that is given in the USER parameter for authentication, we need the
1300same initial quoting as (2) but in this case, the result must NOT be
1301URL-escaped, because it isn't a URL. The way this is handled is by
1302de-URL-quoting the text when processing the USER parameter in
1303control_ldap_search() above. That means that the same quote operator can be
1304used. This has the additional advantage that spaces in the DN won't cause
1305parsing problems. For example:
1306
1307 USER=cn=${quote_ldap_dn:$1},%20dc=example,%20dc=com
1308
1309should be safe if there are spaces in $1.
1310
1311
1312Arguments:
1313 s the string to be quoted
1314 opt additional option text or NULL if none
1315 only "dn" is recognized
1316
1317Returns: the processed string or NULL for a bad option
1318*/
1319
1320
1321
1322/* The characters in this string, together with alphanumerics, never need
1323quoting in any way. */
1324
1325#define ALWAYS_LITERAL "!$'-._"
1326
1327/* The special characters in this string do not need to be URL-quoted. The set
1328is a bit larger than the general literals. */
1329
1330#define URL_NONQUOTE ALWAYS_LITERAL "()*+"
1331
1332/* The following macros define the characters that are quoted by quote_ldap and
1333quote_ldap_dn, respectively. */
1334
1335#define LDAP_QUOTE "*()\\"
1336#define LDAP_DN_QUOTE ",+\"\\<>;"
1337
1338
1339
e6d225ae 1340static uschar *
0756eb3c
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1341eldap_quote(uschar *s, uschar *opt)
1342{
1343register int c;
1344int count = 0;
1345int len = 0;
1346BOOL dn = FALSE;
1347uschar *t = s;
1348uschar *quoted;
1349
1350/* Test for a DN quotation. */
1351
1352if (opt != NULL)
1353 {
1354 if (Ustrcmp(opt, "dn") != 0) return NULL; /* No others recognized */
1355 dn = TRUE;
1356 }
1357
1358/* Compute how much extra store we need for the string. This doesn't have to be
1359exact as long as it isn't an underestimate. The worst case is the addition of 5
1360extra bytes for a single character. This occurs for certain characters in DNs,
1361where, for example, < turns into %5C%3C. For simplicity, we just add 5 for each
1362possibly escaped character. The really fast way would be just to test for
1363non-alphanumerics, but it is probably better to spot a few others that are
1364never escaped, because if there are no specials at all, we can avoid copying
1365the string. */
1366
1367while ((c = *t++) != 0)
1368 {
1369 len++;
1370 if (!isalnum(c) && Ustrchr(ALWAYS_LITERAL, c) == NULL) count += 5;
1371 }
1372if (count == 0) return s;
1373
1374/* Get sufficient store to hold the quoted string */
1375
1376t = quoted = store_get(len + count + 1);
1377
1378/* Handle plain quote_ldap */
1379
1380if (!dn)
1381 {
1382 while ((c = *s++) != 0)
1383 {
1384 if (!isalnum(c))
1385 {
1386 if (Ustrchr(LDAP_QUOTE, c) != NULL)
1387 {
1388 sprintf(CS t, "%%5C%02X", c); /* e.g. * => %5C2A */
1389 t += 5;
1390 continue;
1391 }
1392 if (Ustrchr(URL_NONQUOTE, c) == NULL) /* e.g. ] => %5D */
1393 {
1394 sprintf(CS t, "%%%02X", c);
1395 t += 3;
1396 continue;
1397 }
1398 }
1399 *t++ = c; /* unquoted character */
1400 }
1401 }
1402
1403/* Handle quote_ldap_dn */
1404
1405else
1406 {
1407 uschar *ss = s + len;
1408
1409 /* Find the last char before any trailing spaces */
1410
1411 while (ss > s && ss[-1] == ' ') ss--;
1412
1413 /* Quote leading spaces and sharps */
1414
1415 for (; s < ss; s++)
1416 {
1417 if (*s != ' ' && *s != '#') break;
1418 sprintf(CS t, "%%5C%%%02X", *s);
1419 t += 6;
1420 }
1421
1422 /* Handle the rest of the string, up to the trailing spaces */
1423
1424 while (s < ss)
1425 {
1426 c = *s++;
1427 if (!isalnum(c))
1428 {
1429 if (Ustrchr(LDAP_DN_QUOTE, c) != NULL)
1430 {
1431 Ustrncpy(t, "%5C", 3); /* insert \ where needed */
1432 t += 3; /* fall through to check URL */
1433 }
1434 if (Ustrchr(URL_NONQUOTE, c) == NULL) /* e.g. ] => %5D */
1435 {
1436 sprintf(CS t, "%%%02X", c);
1437 t += 3;
1438 continue;
1439 }
1440 }
1441 *t++ = c; /* unquoted character, or non-URL quoted after %5C */
1442 }
1443
1444 /* Handle the trailing spaces */
1445
1446 while (*ss++ != 0)
1447 {
1448 Ustrncpy(t, "%5C%20", 6);
1449 t += 6;
1450 }
1451 }
1452
1453/* Terminate the new string and return */
1454
1455*t = 0;
1456return quoted;
1457}
1458
e6d225ae
DW
1459static lookup_info ldap_lookup_info = {
1460 US"ldap", /* lookup name */
1461 lookup_querystyle, /* query-style lookup */
1462 eldap_open, /* open function */
1463 NULL, /* check function */
1464 eldap_find, /* find function */
1465 NULL, /* no close function */
1466 eldap_tidy, /* tidy function */
1467 eldap_quote /* quoting function */
1468};
1469
1470static lookup_info ldapdn_lookup_info = {
1471 US"ldapdn", /* lookup name */
1472 lookup_querystyle, /* query-style lookup */
1473 eldap_open, /* sic */ /* open function */
1474 NULL, /* check function */
1475 eldapdn_find, /* find function */
1476 NULL, /* no close function */
1477 eldap_tidy, /* sic */ /* tidy function */
1478 eldap_quote /* sic */ /* quoting function */
1479};
1480
1481static lookup_info ldapm_lookup_info = {
1482 US"ldapm", /* lookup name */
1483 lookup_querystyle, /* query-style lookup */
1484 eldap_open, /* sic */ /* open function */
1485 NULL, /* check function */
1486 eldapm_find, /* find function */
1487 NULL, /* no close function */
1488 eldap_tidy, /* sic */ /* tidy function */
1489 eldap_quote /* sic */ /* quoting function */
1490};
1491
1492#ifdef DYNLOOKUP
1493#define ldap_lookup_module_info _lookup_module_info
1494#endif
1495
1496static lookup_info *_lookup_list[] = { &ldap_lookup_info, &ldapdn_lookup_info, &ldapm_lookup_info };
1497lookup_module_info ldap_lookup_module_info = { LOOKUP_MODULE_INFO_MAGIC, _lookup_list, 3 };
0756eb3c
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1498
1499/* End of lookups/ldap.c */