LDAP: Fix separator for multiple attrs and ldapm
[exim.git] / src / src / lookups / ldap.c
CommitLineData
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1/*************************************************
2* Exim - an Internet mail transport agent *
3*************************************************/
4
3386088d 5/* Copyright (c) University of Cambridge 1995 - 2015 */
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6/* See the file NOTICE for conditions of use and distribution. */
7
8/* Many thanks to Stuart Lynne for contributing the original code for this
9driver. Further contibutions from Michael Haardt, Brian Candler, Barry
10Pederson, Peter Savitch and Christian Kellner. Particular thanks to Brian for
11researching how to handle the different kinds of error. */
12
13
14#include "../exim.h"
15#include "lf_functions.h"
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16
17
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PH
18/* Include LDAP headers. The code below uses some "old" LDAP interfaces that
19are deprecated in OpenLDAP. I don't know their status in other LDAP
20implementations. LDAP_DEPRECATED causes their prototypes to be defined in
21ldap.h. */
22
23#define LDAP_DEPRECATED 1
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24
25#include <lber.h>
26#include <ldap.h>
27
28
29/* Annoyingly, the different LDAP libraries handle errors in different ways,
30and some other things too. There doesn't seem to be an automatic way of
31distinguishing between them. Local/Makefile should contain a setting of
32LDAP_LIB_TYPE, which in turn causes appropriate macros to be defined for the
33different kinds. Those that matter are:
34
35LDAP_LIB_NETSCAPE
36LDAP_LIB_SOLARIS with synonym LDAP_LIB_SOLARIS7
37LDAP_LIB_OPENLDAP2
38
39These others may be defined, but are in fact the default, so are not tested:
40
41LDAP_LIB_UMICHIGAN
42LDAP_LIB_OPENLDAP1
43*/
44
45#if defined(LDAP_LIB_SOLARIS7) && ! defined(LDAP_LIB_SOLARIS)
46#define LDAP_LIB_SOLARIS
47#endif
48
49
50/* Just in case LDAP_NO_LIMIT is not defined by some of these libraries. */
51
52#ifndef LDAP_NO_LIMIT
53#define LDAP_NO_LIMIT 0
54#endif
55
56
57/* Just in case LDAP_DEREF_NEVER is not defined */
58
59#ifndef LDAP_DEREF_NEVER
60#define LDAP_DEREF_NEVER 0
61#endif
62
63
0756eb3c
PH
64/* Four types of LDAP search are implemented */
65
66#define SEARCH_LDAP_MULTIPLE 0 /* Get attributes from multiple entries */
67#define SEARCH_LDAP_SINGLE 1 /* Get attributes from one entry only */
68#define SEARCH_LDAP_DN 2 /* Get just the DN from one entry */
69#define SEARCH_LDAP_AUTH 3 /* Just checking for authentication */
70
71/* In all 4 cases, the DN is left in $ldap_dn (which post-dates the
72SEARCH_LDAP_DN lookup). */
73
74
75/* Structure and anchor for caching connections. */
76
77typedef struct ldap_connection {
78 struct ldap_connection *next;
79 uschar *host;
80 uschar *user;
81 uschar *password;
82 BOOL bound;
83 int port;
a30a8861 84 BOOL is_start_tls_called;
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85 LDAP *ld;
86} LDAP_CONNECTION;
87
88static LDAP_CONNECTION *ldap_connections = NULL;
89
90
91
92/*************************************************
93* Internal search function *
94*************************************************/
95
96/* This is the function that actually does the work. It is called (indirectly
97via control_ldap_search) from eldap_find(), eldapauth_find(), eldapdn_find(),
98and eldapm_find(), with a difference in the "search_type" argument.
99
100The case of eldapauth_find() is special in that all it does is do
101authentication, returning OK or FAIL as appropriate. This isn't used as a
102lookup. Instead, it is called from expand.c as an expansion condition test.
103
104The DN from a successful lookup is placed in $ldap_dn. This feature postdates
105the provision of the SEARCH_LDAP_DN facility for returning just the DN as the
106data.
107
108Arguments:
109 ldap_url the URL to be looked up
110 server server host name, when URL contains none
111 s_port server port, used when URL contains no name
112 search_type SEARCH_LDAP_MULTIPLE allows values from multiple entries
113 SEARCH_LDAP_SINGLE allows values from one entry only
114 SEARCH_LDAP_DN gets the DN from one entry
115 res set to point at the result (not used for ldapauth)
116 errmsg set to point a message if result is not OK
117 defer_break set TRUE if no more servers to be tried after a DEFER
118 user user name for authentication, or NULL
119 password password for authentication, or NULL
120 sizelimit max number of entries returned, or 0 for no limit
121 timelimit max time to wait, or 0 for no limit
d00328e2 122 tcplimit max time for network activity, e.g. connect, or 0 for OS default
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123 deference the dereference option, which is one of
124 LDAP_DEREF_{NEVER,SEARCHING,FINDING,ALWAYS}
6ec97b1b 125 referrals the referral option, which is LDAP_OPT_ON or LDAP_OPT_OFF
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126
127Returns: OK or FAIL or DEFER
128 FAIL is given only if a lookup was performed successfully, but
129 returned no data.
130*/
131
132static int
55414b25
JH
133perform_ldap_search(const uschar *ldap_url, uschar *server, int s_port,
134 int search_type, uschar **res, uschar **errmsg, BOOL *defer_break,
135 uschar *user, uschar *password, int sizelimit, int timelimit, int tcplimit,
136 int dereference, void *referrals)
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PH
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
9494140a 159int attrs_requested = 0;
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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++)
9494140a 251 attrs_requested++;
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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
5428a946
TL
284 #ifdef LDAP_OPT_X_TLS_NEWCTX
285 int am_server = 0;
286 LDAP *ldsetctx;
287 #else
288 LDAP *ldsetctx = NULL;
289 #endif
290
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291
292 /* --------------------------- OpenLDAP ------------------------ */
293
294 /* There seems to be a preference under OpenLDAP for ldap_initialize()
295 instead of ldap_init(), though I have as yet been unable to find
296 documentation that says this. (OpenLDAP documentation is sparse to
297 non-existent). So we handle OpenLDAP differently here. Also, support for
298 ldapi seems to be OpenLDAP-only at present. */
299
300 #ifdef LDAP_LIB_OPENLDAP2
301
302 /* We now need an empty string for the default host. Get some store in which
303 to build a URL for ldap_initialize(). In the ldapi case, it can't be bigger
304 than (9 + 3*Ustrlen(shost)), whereas in the other cases it can't be bigger
305 than the host name + "ldaps:///" plus : and a port number, say 20 + the
306 length of the host name. What we get should accommodate both, easily. */
307
308 uschar *shost = (host == NULL)? US"" : host;
309 uschar *init_url = store_get(20 + 3 * Ustrlen(shost));
310 uschar *init_ptr;
311
312 /* Handle connection via Unix socket ("ldapi"). We build a basic LDAP URI to
313 contain the path name, with slashes escaped as %2F. */
314
315 if (ldapi)
316 {
317 int ch;
318 init_ptr = init_url + 8;
319 Ustrcpy(init_url, "ldapi://");
320 while ((ch = *shost++) != 0)
321 {
322 if (ch == '/')
323 {
324 Ustrncpy(init_ptr, "%2F", 3);
325 init_ptr += 3;
326 }
327 else *init_ptr++ = ch;
328 }
329 *init_ptr = 0;
330 }
331
332 /* This is not an ldapi call. Just build a URI with the protocol type, host
333 name, and port. */
334
335 else
336 {
337 init_ptr = Ustrchr(ldap_url, '/');
338 Ustrncpy(init_url, ldap_url, init_ptr - ldap_url);
339 init_ptr = init_url + (init_ptr - ldap_url);
340 sprintf(CS init_ptr, "//%s:%d/", shost, port);
341 }
342
343 /* Call ldap_initialize() and check the result */
344
345 DEBUG(D_lookup) debug_printf("ldap_initialize with URL %s\n", init_url);
346 rc = ldap_initialize(&ld, CS init_url);
347 if (rc != LDAP_SUCCESS)
348 {
349 *errmsg = string_sprintf("ldap_initialize: (error %d) URL \"%s\"\n",
350 rc, init_url);
351 goto RETURN_ERROR;
352 }
353 store_reset(init_url); /* Might as well save memory when we can */
354
355
356 /* ------------------------- Not OpenLDAP ---------------------- */
357
358 /* For libraries other than OpenLDAP, use ldap_init(). */
359
360 #else /* LDAP_LIB_OPENLDAP2 */
361 ld = ldap_init(CS host, port);
362 #endif /* LDAP_LIB_OPENLDAP2 */
363
364 /* -------------------------------------------------------------- */
365
366
367 /* Handle failure to initialize */
368
369 if (ld == NULL)
370 {
371 *errmsg = string_sprintf("failed to initialize for LDAP server %s%s - %s",
372 host, porttext, strerror(errno));
373 goto RETURN_ERROR;
374 }
375
5428a946
TL
376 #ifdef LDAP_OPT_X_TLS_NEWCTX
377 ldsetctx = ld;
378 #endif
379
0756eb3c
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380 /* Set the TCP connect time limit if available. This is something that is
381 in Netscape SDK v4.1; I don't know about other libraries. */
382
383 #ifdef LDAP_X_OPT_CONNECT_TIMEOUT
7c7ad977
PH
384 if (tcplimit > 0)
385 {
994a09e9 386 int timeout1000 = tcplimit*1000;
7c7ad977
PH
387 ldap_set_option(ld, LDAP_X_OPT_CONNECT_TIMEOUT, (void *)&timeout1000);
388 }
994a09e9
PH
389 else
390 {
391 int notimeout = LDAP_X_IO_TIMEOUT_NO_TIMEOUT;
392 ldap_set_option(ld, LDAP_X_OPT_CONNECT_TIMEOUT, (void *)&notimeout);
393 }
0756eb3c
PH
394 #endif
395
7c7ad977
PH
396 /* Set the TCP connect timeout. This works with OpenLDAP 2.2.14. */
397
398 #ifdef LDAP_OPT_NETWORK_TIMEOUT
399 if (tcplimit > 0)
400 ldap_set_option(ld, LDAP_OPT_NETWORK_TIMEOUT, (void *)timeoutptr);
8e669ac1 401 #endif
7c7ad977 402
0756eb3c
PH
403 /* I could not get TLS to work until I set the version to 3. That version
404 seems to be the default nowadays. The RFC is dated 1997, so I would hope
405 that all the LDAP libraries support it. Therefore, if eldap_version hasn't
406 been set, go for v3 if we can. */
407
408 if (eldap_version < 0)
409 {
410 #ifdef LDAP_VERSION3
411 eldap_version = LDAP_VERSION3;
412 #else
413 eldap_version = 2;
414 #endif
415 }
416
417 #ifdef LDAP_OPT_PROTOCOL_VERSION
418 ldap_set_option(ld, LDAP_OPT_PROTOCOL_VERSION, (void *)&eldap_version);
419 #endif
420
421 DEBUG(D_lookup) debug_printf("initialized for LDAP (v%d) server %s%s\n",
422 eldap_version, host, porttext);
423
424 /* If not using ldapi and TLS is available, set appropriate TLS options: hard
425 for "ldaps" and soft otherwise. */
426
427 #ifdef LDAP_OPT_X_TLS
428 if (!ldapi)
429 {
430 int tls_option;
33382dd9
TL
431 #ifdef LDAP_OPT_X_TLS_REQUIRE_CERT
432 if (eldap_require_cert != NULL)
433 {
434 tls_option = LDAP_OPT_X_TLS_NEVER;
435 if (Ustrcmp(eldap_require_cert, "hard") == 0)
436 {
437 tls_option = LDAP_OPT_X_TLS_HARD;
438 }
439 else if (Ustrcmp(eldap_require_cert, "demand") == 0)
440 {
441 tls_option = LDAP_OPT_X_TLS_DEMAND;
442 }
443 else if (Ustrcmp(eldap_require_cert, "allow") == 0)
444 {
445 tls_option = LDAP_OPT_X_TLS_ALLOW;
446 }
447 else if (Ustrcmp(eldap_require_cert, "try") == 0)
448 {
449 tls_option = LDAP_OPT_X_TLS_TRY;
450 }
451 DEBUG(D_lookup)
452 debug_printf("Require certificate overrides LDAP_OPT_X_TLS option (%d)\n",
453 tls_option);
454 }
455 else
456 #endif /* LDAP_OPT_X_TLS_REQUIRE_CERT */
0756eb3c
PH
457 if (strncmp(ludp->lud_scheme, "ldaps", 5) == 0)
458 {
459 tls_option = LDAP_OPT_X_TLS_HARD;
33382dd9
TL
460 DEBUG(D_lookup)
461 debug_printf("LDAP_OPT_X_TLS_HARD set due to ldaps:// URI\n");
0756eb3c
PH
462 }
463 else
464 {
465 tls_option = LDAP_OPT_X_TLS_TRY;
33382dd9
TL
466 DEBUG(D_lookup)
467 debug_printf("LDAP_OPT_X_TLS_TRY set due to ldap:// URI\n");
0756eb3c
PH
468 }
469 ldap_set_option(ld, LDAP_OPT_X_TLS, (void *)&tls_option);
470 }
471 #endif /* LDAP_OPT_X_TLS */
472
bc19a55b
PP
473 #ifdef LDAP_OPT_X_TLS_CACERTFILE
474 if (eldap_ca_cert_file != NULL)
475 {
5428a946 476 ldap_set_option(ldsetctx, LDAP_OPT_X_TLS_CACERTFILE, eldap_ca_cert_file);
bc19a55b
PP
477 }
478 #endif
479 #ifdef LDAP_OPT_X_TLS_CACERTDIR
480 if (eldap_ca_cert_dir != NULL)
481 {
5428a946 482 ldap_set_option(ldsetctx, LDAP_OPT_X_TLS_CACERTDIR, eldap_ca_cert_dir);
bc19a55b
PP
483 }
484 #endif
485 #ifdef LDAP_OPT_X_TLS_CERTFILE
486 if (eldap_cert_file != NULL)
487 {
5428a946 488 ldap_set_option(ldsetctx, LDAP_OPT_X_TLS_CERTFILE, eldap_cert_file);
bc19a55b
PP
489 }
490 #endif
491 #ifdef LDAP_OPT_X_TLS_KEYFILE
492 if (eldap_cert_key != NULL)
493 {
5428a946 494 ldap_set_option(ldsetctx, LDAP_OPT_X_TLS_KEYFILE, eldap_cert_key);
bc19a55b
PP
495 }
496 #endif
497 #ifdef LDAP_OPT_X_TLS_CIPHER_SUITE
498 if (eldap_cipher_suite != NULL)
499 {
5428a946 500 ldap_set_option(ldsetctx, LDAP_OPT_X_TLS_CIPHER_SUITE, eldap_cipher_suite);
bc19a55b
PP
501 }
502 #endif
503 #ifdef LDAP_OPT_X_TLS_REQUIRE_CERT
504 if (eldap_require_cert != NULL)
505 {
506 int cert_option = LDAP_OPT_X_TLS_NEVER;
507 if (Ustrcmp(eldap_require_cert, "hard") == 0)
508 {
509 cert_option = LDAP_OPT_X_TLS_HARD;
510 }
511 else if (Ustrcmp(eldap_require_cert, "demand") == 0)
512 {
513 cert_option = LDAP_OPT_X_TLS_DEMAND;
514 }
515 else if (Ustrcmp(eldap_require_cert, "allow") == 0)
516 {
517 cert_option = LDAP_OPT_X_TLS_ALLOW;
518 }
519 else if (Ustrcmp(eldap_require_cert, "try") == 0)
520 {
521 cert_option = LDAP_OPT_X_TLS_TRY;
522 }
5428a946
TL
523 /* This ldap handle is set at compile time based on client libs. Older
524 * versions want it to be global and newer versions can force a reload
525 * of the TLS context (to reload these settings we are changing from the
526 * default that loaded at instantiation). */
527 rc = ldap_set_option(ldsetctx, LDAP_OPT_X_TLS_REQUIRE_CERT, &cert_option);
528 if (rc)
529 {
530 DEBUG(D_lookup)
531 debug_printf("Unable to set TLS require cert_option(%d) globally: %s\n",
532 cert_option, ldap_err2string(rc));
533 }
534 }
535 #endif
536 #ifdef LDAP_OPT_X_TLS_NEWCTX
537 rc = ldap_set_option(ldsetctx, LDAP_OPT_X_TLS_NEWCTX, &am_server);
538 if (rc)
539 {
540 DEBUG(D_lookup)
541 debug_printf("Unable to reload TLS context %d: %s\n",
542 rc, ldap_err2string(rc));
bc19a55b
PP
543 }
544 #endif
545
0756eb3c
PH
546 /* Now add this connection to the chain of cached connections */
547
548 lcp = store_get(sizeof(LDAP_CONNECTION));
549 lcp->host = (host == NULL)? NULL : string_copy(host);
550 lcp->bound = FALSE;
551 lcp->user = NULL;
552 lcp->password = NULL;
553 lcp->port = port;
554 lcp->ld = ld;
555 lcp->next = ldap_connections;
a30a8861 556 lcp->is_start_tls_called = FALSE;
0756eb3c
PH
557 ldap_connections = lcp;
558 }
559
560/* Found cached connection */
561
562else
563 {
564 DEBUG(D_lookup)
565 debug_printf("re-using cached connection to LDAP server %s%s\n",
566 host, porttext);
567 }
568
569/* Bind with the user/password supplied, or an anonymous bind if these values
570are NULL, unless a cached connection is already bound with the same values. */
571
572if (!lcp->bound ||
573 (lcp->user == NULL && user != NULL) ||
574 (lcp->user != NULL && user == NULL) ||
575 (lcp->user != NULL && user != NULL && Ustrcmp(lcp->user, user) != 0) ||
576 (lcp->password == NULL && password != NULL) ||
577 (lcp->password != NULL && password == NULL) ||
578 (lcp->password != NULL && password != NULL &&
579 Ustrcmp(lcp->password, password) != 0))
580 {
581 DEBUG(D_lookup) debug_printf("%sbinding with user=%s password=%s\n",
582 (lcp->bound)? "re-" : "", user, password);
a30a8861 583 if (eldap_start_tls && !lcp->is_start_tls_called)
bc19a55b 584 {
d13cdd30
PP
585#if defined(LDAP_OPT_X_TLS) && !defined(LDAP_LIB_SOLARIS)
586 /* The Oracle LDAP libraries (LDAP_LIB_TYPE=SOLARIS) don't support this.
587 * Note: moreover, they appear to now define LDAP_OPT_X_TLS and still not
588 * export an ldap_start_tls_s symbol.
589 */
590 if ( (rc = ldap_start_tls_s(lcp->ld, NULL, NULL)) != LDAP_SUCCESS)
591 {
592 *errmsg = string_sprintf("failed to initiate TLS processing on an "
593 "LDAP session to server %s%s - ldap_start_tls_s() returned %d:"
594 " %s", host, porttext, rc, ldap_err2string(rc));
595 goto RETURN_ERROR;
596 }
a30a8861 597 lcp->is_start_tls_called = TRUE;
d13cdd30
PP
598#else
599 DEBUG(D_lookup)
600 debug_printf("TLS initiation not supported with this Exim and your LDAP library.\n");
867fcbf5 601#endif
d13cdd30 602 }
7c7ad977
PH
603 if ((msgid = ldap_bind(lcp->ld, CS user, CS password, LDAP_AUTH_SIMPLE))
604 == -1)
0756eb3c 605 {
7c7ad977 606 *errmsg = string_sprintf("failed to bind the LDAP connection to server "
d00328e2 607 "%s%s - ldap_bind() returned -1", host, porttext);
7c7ad977
PH
608 goto RETURN_ERROR;
609 }
0756eb3c 610
7c7ad977
PH
611 if ((rc = ldap_result( lcp->ld, msgid, 1, timeoutptr, &result )) <= 0)
612 {
613 *errmsg = string_sprintf("failed to bind the LDAP connection to server "
8e669ac1 614 "%s%s - LDAP error: %s", host, porttext,
7c7ad977
PH
615 rc == -1 ? "result retrieval failed" : "timeout" );
616 result = NULL;
617 goto RETURN_ERROR;
618 }
619
620 rc = ldap_result2error( lcp->ld, result, 0 );
621
622 /* Invalid credentials when just checking credentials returns FAIL. This
623 stops any further servers being tried. */
0756eb3c 624
7c7ad977
PH
625 if (search_type == SEARCH_LDAP_AUTH && rc == LDAP_INVALID_CREDENTIALS)
626 {
627 DEBUG(D_lookup)
628 debug_printf("Invalid credentials: ldapauth returns FAIL\n");
629 error_yield = FAIL;
630 goto RETURN_ERROR_NOMSG;
631 }
0756eb3c 632
7c7ad977
PH
633 /* Otherwise we have a problem that doesn't stop further servers from being
634 tried. */
635
636 if (rc != LDAP_SUCCESS)
637 {
0756eb3c
PH
638 *errmsg = string_sprintf("failed to bind the LDAP connection to server "
639 "%s%s - LDAP error %d: %s", host, porttext, rc, ldap_err2string(rc));
640 goto RETURN_ERROR;
641 }
642
643 /* Successful bind */
644
645 lcp->bound = TRUE;
646 lcp->user = (user == NULL)? NULL : string_copy(user);
647 lcp->password = (password == NULL)? NULL : string_copy(password);
7c7ad977
PH
648
649 ldap_msgfree(result);
650 result = NULL;
0756eb3c
PH
651 }
652
653/* If we are just checking credentials, return OK. */
654
655if (search_type == SEARCH_LDAP_AUTH)
656 {
657 DEBUG(D_lookup) debug_printf("Bind succeeded: ldapauth returns OK\n");
658 goto RETURN_OK;
659 }
660
661/* Before doing the search, set the time and size limits (if given). Here again
662the different implementations of LDAP have chosen to do things differently. */
663
664#if defined(LDAP_OPT_SIZELIMIT)
665ldap_set_option(lcp->ld, LDAP_OPT_SIZELIMIT, (void *)&sizelimit);
666ldap_set_option(lcp->ld, LDAP_OPT_TIMELIMIT, (void *)&timelimit);
667#else
668lcp->ld->ld_sizelimit = sizelimit;
669lcp->ld->ld_timelimit = timelimit;
670#endif
671
672/* Similarly for dereferencing aliases. Don't know if this is possible on
673an LDAP library without LDAP_OPT_DEREF. */
674
675#if defined(LDAP_OPT_DEREF)
676ldap_set_option(lcp->ld, LDAP_OPT_DEREF, (void *)&dereference);
677#endif
678
6ec97b1b
PH
679/* Similarly for the referral setting; should the library follow referrals that
680the LDAP server returns? The conditional is just in case someone uses a library
681without it. */
682
683#if defined(LDAP_OPT_REFERRALS)
684ldap_set_option(lcp->ld, LDAP_OPT_REFERRALS, referrals);
685#endif
686
0756eb3c
PH
687/* Start the search on the server. */
688
689DEBUG(D_lookup) debug_printf("Start search\n");
690
691msgid = ldap_search(lcp->ld, ludp->lud_dn, ludp->lud_scope, ludp->lud_filter,
692 ludp->lud_attrs, 0);
693
694if (msgid == -1)
695 {
3ca0ba97
PH
696 #if defined LDAP_LIB_SOLARIS || defined LDAP_LIB_OPENLDAP2
697 int err;
698 ldap_get_option(lcp->ld, LDAP_OPT_ERROR_NUMBER, &err);
8e669ac1 699 *errmsg = string_sprintf("ldap_search failed: %d, %s", err,
3ca0ba97 700 ldap_err2string(err));
8e669ac1
PH
701
702 #else
3ca0ba97
PH
703 *errmsg = string_sprintf("ldap_search failed");
704 #endif
8e669ac1 705
0756eb3c
PH
706 goto RETURN_ERROR;
707 }
708
709/* Loop to pick up results as they come in, setting a timeout if one was
710given. */
711
0756eb3c
PH
712while ((rc = ldap_result(lcp->ld, msgid, 0, timeoutptr, &result)) ==
713 LDAP_RES_SEARCH_ENTRY)
714 {
715 LDAPMessage *e;
bb4fd71d
HSHR
716 int valuecount; /* We can see an attr spread across several
717 entries. If B is derived from A and we request
718 A and the directory contains both, A and B,
719 then we get two entries, one for A and one for B.
720 Here we just count the values per entry */
0756eb3c 721
694678d0 722 DEBUG(D_lookup) debug_printf("LDAP result loop\n");
0756eb3c 723
bb4fd71d 724 for(e = ldap_first_entry(lcp->ld, result), valuecount = 0;
0756eb3c
PH
725 e != NULL;
726 e = ldap_next_entry(lcp->ld, e))
727 {
728 uschar *new_dn;
729 BOOL insert_space = FALSE;
730
731 DEBUG(D_lookup) debug_printf("LDAP entry loop\n");
732
733 rescount++; /* Count results */
734
735 /* Results for multiple entries values are separated by newlines. */
736
737 if (data != NULL) data = string_cat(data, &size, &ptr, US"\n", 1);
738
739 /* Get the DN from the last result. */
740
741 new_dn = US ldap_get_dn(lcp->ld, e);
742 if (new_dn != NULL)
743 {
744 if (dn != NULL)
745 {
746 #if defined LDAP_LIB_NETSCAPE || defined LDAP_LIB_OPENLDAP2
747 ldap_memfree(dn);
748 #else /* OPENLDAP 1, UMich, Solaris */
749 free(dn);
750 #endif
751 }
752 /* Save for later */
753 dn = new_dn;
754 }
755
756 /* If the data we want is actually the DN rather than any attribute values,
757 (an "ldapdn" search) add it to the data string. If there are multiple
758 entries, the DNs will be concatenated, but we test for this case below, as
759 for SEARCH_LDAP_SINGLE, and give an error. */
760
761 if (search_type == SEARCH_LDAP_DN) /* Do not amalgamate these into one */
762 { /* condition, because of the else */
763 if (new_dn != NULL) /* below, that's for the first only */
764 {
765 data = string_cat(data, &size, &ptr, new_dn, Ustrlen(new_dn));
766 data[ptr] = 0;
767 attribute_found = TRUE;
768 }
769 }
770
771 /* Otherwise, loop through the entry, grabbing attribute values. If there's
772 only one attribute being retrieved, no attribute name is given, and the
3a2ac12b 773 result is not quoted. Multiple values are separated by (comma).
0756eb3c 774 If more than one attribute is being retrieved, the data is given as a
3a2ac12b
HSHR
775 sequence of name=value pairs, separated by (space), with the value always in quotes.
776 If there are multiple values, they are given within the quotes, comma separated. */
0756eb3c
PH
777
778 else for (attr = US ldap_first_attribute(lcp->ld, e, &ber);
779 attr != NULL;
780 attr = US ldap_next_attribute(lcp->ld, e, ber))
781 {
694678d0 782 DEBUG(D_lookup) debug_printf("LDAP attr loop\n");
bb4fd71d
HSHR
783
784 /* In case of attrs_requested == 1 we just count the values, in all other cases
785 (0, >1) we count the values per attribute */
786 if (attrs_requested != 1) valuecount = 0;
787
0756eb3c
PH
788 if (attr[0] != 0)
789 {
790 /* Get array of values for this attribute. */
791
792 if ((firstval = values = USS ldap_get_values(lcp->ld, e, CS attr))
793 != NULL)
794 {
9494140a
HSHR
795
796 if (attrs_requested != 1)
0756eb3c
PH
797 {
798 if (insert_space)
799 data = string_cat(data, &size, &ptr, US" ", 1);
800 else
801 insert_space = TRUE;
802 data = string_cat(data, &size, &ptr, attr, Ustrlen(attr));
803 data = string_cat(data, &size, &ptr, US"=\"", 2);
804 }
805
806 while (*values != NULL)
807 {
808 uschar *value = *values;
809 int len = Ustrlen(value);
bb4fd71d 810 ++valuecount;
0756eb3c 811
694678d0
HSHR
812 DEBUG(D_lookup) debug_printf("LDAP value loop %s:%s\n", attr, value);
813
734e448e
HSHR
814 /* In case we requested one attribute only but got several times
815 into that attr loop, we need to append the additional values.
816 (This may happen if you derive attributeTypes B and C from A and
817 then query for A.) In all other cases we detect the different
818 attribute and append only every non first value. */
0756eb3c 819
bb4fd71d 820 if (data && valuecount > 1)
7bba24eb 821 data = string_cat(data, &size, &ptr, US",", 1);
0756eb3c
PH
822
823 /* For multiple attributes, the data is in quotes. We must escape
7bba24eb 824 internal quotes, backslashes, newlines, and must double commas. */
0756eb3c 825
9494140a 826 if (attrs_requested != 1)
0756eb3c
PH
827 {
828 int j;
829 for (j = 0; j < len; j++)
830 {
831 if (value[j] == '\n')
832 data = string_cat(data, &size, &ptr, US"\\n", 2);
7bba24eb
JH
833 else if (value[j] == ',')
834 data = string_cat(data, &size, &ptr, US",,", 2);
0756eb3c
PH
835 else
836 {
837 if (value[j] == '\"' || value[j] == '\\')
838 data = string_cat(data, &size, &ptr, US"\\", 1);
839 data = string_cat(data, &size, &ptr, value+j, 1);
840 }
841 }
842 }
843
7bba24eb
JH
844 /* For single attributes, just double commas */
845
846 else
847 {
848 int j;
849 for (j = 0; j < len; j++)
850 {
851 if (value[j] == ',')
852 data = string_cat(data, &size, &ptr, US",,", 2);
853 else
854 data = string_cat(data, &size, &ptr, value+j, 1);
855 }
856 }
0756eb3c 857
0756eb3c
PH
858
859 /* Move on to the next value */
860
861 values++;
862 attribute_found = TRUE;
863 }
864
865 /* Closing quote at the end of the data for a named attribute. */
866
9494140a 867 if (attrs_requested != 1)
0756eb3c
PH
868 data = string_cat(data, &size, &ptr, US"\"", 1);
869
870 /* Free the values */
871
872 ldap_value_free(CSS firstval);
873 }
874 }
875
876 #if defined LDAP_LIB_NETSCAPE || defined LDAP_LIB_OPENLDAP2
877
878 /* Netscape and OpenLDAP2 LDAP's attrs are dynamically allocated and need
879 to be freed. UMich LDAP stores them in static storage and does not require
880 this. */
881
882 ldap_memfree(attr);
883 #endif
884 } /* End "for" loop for extracting attributes from an entry */
885 } /* End "for" loop for extracting entries from a result */
886
887 /* Free the result */
888
889 ldap_msgfree(result);
890 result = NULL;
891 } /* End "while" loop for multiple results */
892
893/* Terminate the dynamic string that we have built and reclaim unused store */
894
895if (data != NULL)
896 {
897 data[ptr] = 0;
898 store_reset(data + ptr + 1);
899 }
900
901/* Copy the last dn into eldap_dn */
902
903if (dn != NULL)
904 {
905 eldap_dn = string_copy(dn);
906 #if defined LDAP_LIB_NETSCAPE || defined LDAP_LIB_OPENLDAP2
907 ldap_memfree(dn);
908 #else /* OPENLDAP 1, UMich, Solaris */
909 free(dn);
910 #endif
911 }
912
913DEBUG(D_lookup) debug_printf("search ended by ldap_result yielding %d\n",rc);
914
915if (rc == 0)
916 {
917 *errmsg = US"ldap_result timed out";
918 goto RETURN_ERROR;
919 }
920
921/* A return code of -1 seems to mean "ldap_result failed internally or couldn't
922provide you with a message". Other error states seem to exist where
923ldap_result() didn't give us any message from the server at all, leaving result
924set to NULL. Apparently, "the error parameters of the LDAP session handle will
925be set accordingly". That's the best we can do to retrieve an error status; we
926can't use functions like ldap_result2error because they parse a message from
927the server, which we didn't get.
928
929Annoyingly, the different implementations of LDAP have gone for different
930methods of handling error codes and generating error messages. */
931
932if (rc == -1 || result == NULL)
933 {
934 int err;
935 DEBUG(D_lookup) debug_printf("ldap_result failed\n");
936
937 #if defined LDAP_LIB_SOLARIS || defined LDAP_LIB_OPENLDAP2
938 ldap_get_option(lcp->ld, LDAP_OPT_ERROR_NUMBER, &err);
939 *errmsg = string_sprintf("ldap_result failed: %d, %s",
940 err, ldap_err2string(err));
941
942 #elif defined LDAP_LIB_NETSCAPE
943 /* Dubious (surely 'matched' is spurious here?) */
944 (void)ldap_get_lderrno(lcp->ld, &matched, &error1);
945 *errmsg = string_sprintf("ldap_result failed: %s (%s)", error1, matched);
946
947 #else /* UMich LDAP aka OpenLDAP 1.x */
948 *errmsg = string_sprintf("ldap_result failed: %d, %s",
949 lcp->ld->ld_errno, ldap_err2string(lcp->ld->ld_errno));
950 #endif
951
952 goto RETURN_ERROR;
953 }
954
955/* A return code that isn't -1 doesn't necessarily mean there were no problems
8e669ac1
PH
956with the search. The message must be an LDAP_RES_SEARCH_RESULT or
957LDAP_RES_SEARCH_REFERENCE or else it's something we can't handle. Some versions
958of LDAP do not define LDAP_RES_SEARCH_REFERENCE (LDAP v1 is one, it seems). So
3295e65b
PH
959we don't provide that functionality when we can't. :-) */
960
8e669ac1 961if (rc != LDAP_RES_SEARCH_RESULT
3295e65b
PH
962#ifdef LDAP_RES_SEARCH_REFERENCE
963 && rc != LDAP_RES_SEARCH_REFERENCE
8e669ac1 964#endif
3295e65b 965 )
0756eb3c
PH
966 {
967 *errmsg = string_sprintf("ldap_result returned unexpected code %d", rc);
968 goto RETURN_ERROR;
969 }
970
971/* We have a result message from the server. This doesn't yet mean all is well.
972We need to parse the message to find out exactly what's happened. */
973
d38f8232
PH
974#if defined LDAP_LIB_SOLARIS || defined LDAP_LIB_OPENLDAP2
975 ldap_rc = rc;
8e669ac1 976 ldap_parse_rc = ldap_parse_result(lcp->ld, result, &rc, CSS &matched,
d38f8232
PH
977 CSS &error2, NULL, NULL, 0);
978 DEBUG(D_lookup) debug_printf("ldap_parse_result: %d\n", ldap_parse_rc);
8e669ac1 979 if (ldap_parse_rc < 0 &&
3295e65b 980 (ldap_parse_rc != LDAP_NO_RESULTS_RETURNED
8e669ac1 981 #ifdef LDAP_RES_SEARCH_REFERENCE
3295e65b 982 || ldap_rc != LDAP_RES_SEARCH_REFERENCE
8e669ac1 983 #endif
3295e65b 984 ))
0756eb3c 985 {
d38f8232 986 *errmsg = string_sprintf("ldap_parse_result failed %d", ldap_parse_rc);
0756eb3c
PH
987 goto RETURN_ERROR;
988 }
989 error1 = US ldap_err2string(rc);
990
991#elif defined LDAP_LIB_NETSCAPE
992 /* Dubious (it doesn't reference 'result' at all!) */
993 rc = ldap_get_lderrno(lcp->ld, &matched, &error1);
994
995#else /* UMich LDAP aka OpenLDAP 1.x */
996 rc = ldap_result2error(lcp->ld, result, 0);
997 error1 = ldap_err2string(rc);
998 error2 = lcp->ld->ld_error;
999 matched = lcp->ld->ld_matched;
1000#endif
1001
1002/* Process the status as follows:
1003
1004 (1) If we get LDAP_SIZELIMIT_EXCEEDED, just carry on, to return the
1005 truncated result list.
1006
21eb6e72
PH
1007 (2) If we get LDAP_RES_SEARCH_REFERENCE, also just carry on. This was a
1008 submitted patch that is reported to "do the right thing" with Solaris
1009 LDAP libraries. (The problem it addresses apparently does not occur with
1010 Open LDAP.)
1011
1012 (3) The range of errors defined by LDAP_NAME_ERROR generally mean "that
0756eb3c
PH
1013 object does not, or cannot, exist in the database". For those cases we
1014 fail the lookup.
1015
21eb6e72 1016 (4) All other non-successes here are treated as some kind of problem with
0756eb3c
PH
1017 the lookup, so return DEFER (which is the default in error_yield).
1018*/
1019
1020DEBUG(D_lookup) debug_printf("ldap_parse_result yielded %d: %s\n",
1021 rc, ldap_err2string(rc));
1022
21eb6e72
PH
1023if (rc != LDAP_SUCCESS && rc != LDAP_SIZELIMIT_EXCEEDED
1024 #ifdef LDAP_RES_SEARCH_REFERENCE
1025 && rc != LDAP_RES_SEARCH_REFERENCE
1026 #endif
1027 )
0756eb3c
PH
1028 {
1029 *errmsg = string_sprintf("LDAP search failed - error %d: %s%s%s%s%s",
1030 rc,
1031 (error1 != NULL)? error1 : US"",
1032 (error2 != NULL && error2[0] != 0)? US"/" : US"",
1033 (error2 != NULL)? error2 : US"",
1034 (matched != NULL && matched[0] != 0)? US"/" : US"",
1035 (matched != NULL)? matched : US"");
1036
1037 #if defined LDAP_NAME_ERROR
1038 if (LDAP_NAME_ERROR(rc))
1039 #elif defined NAME_ERROR /* OPENLDAP1 calls it this */
1040 if (NAME_ERROR(rc))
1041 #else
1042 if (rc == LDAP_NO_SUCH_OBJECT)
1043 #endif
1044
1045 {
1046 DEBUG(D_lookup) debug_printf("lookup failure forced\n");
1047 error_yield = FAIL;
1048 }
1049 goto RETURN_ERROR;
1050 }
1051
1052/* The search succeeded. Check if we have too many results */
1053
1054if (search_type != SEARCH_LDAP_MULTIPLE && rescount > 1)
1055 {
1056 *errmsg = string_sprintf("LDAP search: more than one entry (%d) was returned "
1057 "(filter not specific enough?)", rescount);
1058 goto RETURN_ERROR_BREAK;
1059 }
1060
1061/* Check if we have too few (zero) entries */
1062
1063if (rescount < 1)
1064 {
1065 *errmsg = string_sprintf("LDAP search: no results");
1066 error_yield = FAIL;
1067 goto RETURN_ERROR_BREAK;
1068 }
1069
1070/* If an entry was found, but it had no attributes, we behave as if no entries
1071were found, that is, the lookup failed. */
1072
1073if (!attribute_found)
1074 {
1075 *errmsg = US"LDAP search: found no attributes";
1076 error_yield = FAIL;
1077 goto RETURN_ERROR;
1078 }
1079
1080/* Otherwise, it's all worked */
1081
1082DEBUG(D_lookup) debug_printf("LDAP search: returning: %s\n", data);
1083*res = data;
1084
1085RETURN_OK:
1086if (result != NULL) ldap_msgfree(result);
1087ldap_free_urldesc(ludp);
1088return OK;
1089
1090/* Error returns */
1091
1092RETURN_ERROR_BREAK:
1093*defer_break = TRUE;
1094
1095RETURN_ERROR:
1096DEBUG(D_lookup) debug_printf("%s\n", *errmsg);
1097
1098RETURN_ERROR_NOMSG:
1099if (result != NULL) ldap_msgfree(result);
1100if (ludp != NULL) ldap_free_urldesc(ludp);
1101
1102#if defined LDAP_LIB_OPENLDAP2
1103 if (error2 != NULL) ldap_memfree(error2);
1104 if (matched != NULL) ldap_memfree(matched);
1105#endif
1106
1107return error_yield;
1108}
1109
1110
1111
1112/*************************************************
1113* Internal search control function *
1114*************************************************/
1115
1116/* This function is called from eldap_find(), eldapauth_find(), eldapdn_find(),
1117and eldapm_find() with a difference in the "search_type" argument. It controls
1118calls to perform_ldap_search() which actually does the work. We call that
1119repeatedly for certain types of defer in the case when the URL contains no host
1120name and eldap_default_servers is set to a list of servers to try. This gives
1121more control than just passing over a list of hosts to ldap_open() because it
1122handles other kinds of defer as well as just a failure to open. Note that the
1123URL is defined to contain either zero or one "hostport" only.
1124
1125Parameter data in addition to the URL can be passed as preceding text in the
1126string, as items of the form XXX=yyy. The URL itself can be detected because it
1127must begin "ldapx://", where x is empty, s, or i.
1128
1129Arguments:
1130 ldap_url the URL to be looked up, optionally preceded by other parameter
1131 settings
1132 search_type SEARCH_LDAP_MULTIPLE allows values from multiple entries
1133 SEARCH_LDAP_SINGLE allows values from one entry only
1134 SEARCH_LDAP_DN gets the DN from one entry
1135 res set to point at the result
1136 errmsg set to point a message if result is not OK
1137
1138Returns: OK or FAIL or DEFER
1139*/
1140
1141static int
55414b25 1142control_ldap_search(const uschar *ldap_url, int search_type, uschar **res,
0756eb3c
PH
1143 uschar **errmsg)
1144{
1145BOOL defer_break = FALSE;
1146int timelimit = LDAP_NO_LIMIT;
1147int sizelimit = LDAP_NO_LIMIT;
7c7ad977 1148int tcplimit = 0;
0756eb3c 1149int sep = 0;
6ec97b1b
PH
1150int dereference = LDAP_DEREF_NEVER;
1151void* referrals = LDAP_OPT_ON;
55414b25
JH
1152const uschar *url = ldap_url;
1153const uschar *p;
0756eb3c
PH
1154uschar *user = NULL;
1155uschar *password = NULL;
deae092e 1156uschar *local_servers = NULL;
55414b25
JH
1157uschar *server;
1158const uschar *list;
0756eb3c
PH
1159uschar buffer[512];
1160
1161while (isspace(*url)) url++;
1162
1163/* Until the string begins "ldap", search for the other parameter settings that
1164are recognized. They are of the form NAME=VALUE, with the value being
1165optionally double-quoted. There must still be a space after it, however. No
1166NAME has the value "ldap". */
1167
1168while (strncmpic(url, US"ldap", 4) != 0)
1169 {
55414b25 1170 const uschar *name = url;
0756eb3c
PH
1171 while (*url != 0 && *url != '=') url++;
1172 if (*url == '=')
1173 {
1174 int namelen;
1175 uschar *value;
1176 namelen = ++url - name;
1177 value = string_dequote(&url);
1178 if (isspace(*url))
1179 {
1180 if (strncmpic(name, US"USER=", namelen) == 0) user = value;
1181 else if (strncmpic(name, US"PASS=", namelen) == 0) password = value;
1182 else if (strncmpic(name, US"SIZE=", namelen) == 0) sizelimit = Uatoi(value);
1183 else if (strncmpic(name, US"TIME=", namelen) == 0) timelimit = Uatoi(value);
7c7ad977
PH
1184 else if (strncmpic(name, US"CONNECT=", namelen) == 0) tcplimit = Uatoi(value);
1185 else if (strncmpic(name, US"NETTIME=", namelen) == 0) tcplimit = Uatoi(value);
deae092e 1186 else if (strncmpic(name, US"SERVERS=", namelen) == 0) local_servers = value;
0756eb3c
PH
1187
1188 /* Don't know if all LDAP libraries have LDAP_OPT_DEREF */
1189
1190 #ifdef LDAP_OPT_DEREF
1191 else if (strncmpic(name, US"DEREFERENCE=", namelen) == 0)
1192 {
1193 if (strcmpic(value, US"never") == 0) dereference = LDAP_DEREF_NEVER;
1194 else if (strcmpic(value, US"searching") == 0)
1195 dereference = LDAP_DEREF_SEARCHING;
1196 else if (strcmpic(value, US"finding") == 0)
1197 dereference = LDAP_DEREF_FINDING;
1198 if (strcmpic(value, US"always") == 0) dereference = LDAP_DEREF_ALWAYS;
1199 }
1200 #else
1201 else if (strncmpic(name, US"DEREFERENCE=", namelen) == 0)
1202 {
1203 *errmsg = string_sprintf("LDAP_OP_DEREF not defined in this LDAP "
1204 "library - cannot use \"dereference\"");
1205 DEBUG(D_lookup) debug_printf("%s\n", *errmsg);
1206 return DEFER;
1207 }
6ec97b1b 1208 #endif
0756eb3c 1209
6ec97b1b
PH
1210 #ifdef LDAP_OPT_REFERRALS
1211 else if (strncmpic(name, US"REFERRALS=", namelen) == 0)
1212 {
1213 if (strcmpic(value, US"follow") == 0) referrals = LDAP_OPT_ON;
1214 else if (strcmpic(value, US"nofollow") == 0) referrals = LDAP_OPT_OFF;
1215 else
1216 {
1217 *errmsg = string_sprintf("LDAP option REFERRALS is not \"follow\" "
1218 "or \"nofollow\"");
1219 DEBUG(D_lookup) debug_printf("%s\n", *errmsg);
1220 return DEFER;
1221 }
1222 }
1223 #else
1224 else if (strncmpic(name, US"REFERRALS=", namelen) == 0)
1225 {
1226 *errmsg = string_sprintf("LDAP_OP_REFERRALS not defined in this LDAP "
1227 "library - cannot use \"referrals\"");
1228 DEBUG(D_lookup) debug_printf("%s\n", *errmsg);
1229 return DEFER;
1230 }
0756eb3c
PH
1231 #endif
1232
1233 else
1234 {
1235 *errmsg =
1236 string_sprintf("unknown parameter \"%.*s\" precedes LDAP URL",
1237 namelen, name);
1238 DEBUG(D_lookup) debug_printf("LDAP query error: %s\n", *errmsg);
1239 return DEFER;
1240 }
1241 while (isspace(*url)) url++;
1242 continue;
1243 }
1244 }
1245 *errmsg = US"malformed parameter setting precedes LDAP URL";
1246 DEBUG(D_lookup) debug_printf("LDAP query error: %s\n", *errmsg);
1247 return DEFER;
1248 }
1249
1250/* If user is set, de-URL-quote it. Some LDAP libraries do this for themselves,
1251but it seems that not all behave like this. The DN for the user is often the
1252result of ${quote_ldap_dn:...} quoting, which does apply URL quoting, because
1253that is needed when the DN is used as a base DN in a query. Sigh. This is all
1254far too complicated. */
1255
1256if (user != NULL)
1257 {
1258 uschar *s;
1259 uschar *t = user;
1260 for (s = user; *s != 0; s++)
1261 {
1262 int c, d;
1263 if (*s == '%' && isxdigit(c=s[1]) && isxdigit(d=s[2]))
1264 {
1265 c = tolower(c);
1266 d = tolower(d);
1267 *t++ =
1268 (((c >= 'a')? (10 + c - 'a') : c - '0') << 4) |
1269 ((d >= 'a')? (10 + d - 'a') : d - '0');
1270 s += 2;
1271 }
1272 else *t++ = *s;
1273 }
1274 *t = 0;
1275 }
1276
1277DEBUG(D_lookup)
1278 debug_printf("LDAP parameters: user=%s pass=%s size=%d time=%d connect=%d "
6ec97b1b
PH
1279 "dereference=%d referrals=%s\n", user, password, sizelimit, timelimit,
1280 tcplimit, dereference, (referrals == LDAP_OPT_ON)? "on" : "off");
0756eb3c
PH
1281
1282/* If the request is just to check authentication, some credentials must
1283be given. The password must not be empty because LDAP binds with an empty
1284password are considered anonymous, and will succeed on most installations. */
1285
1286if (search_type == SEARCH_LDAP_AUTH)
1287 {
1288 if (user == NULL || password == NULL)
1289 {
1290 *errmsg = US"ldapauth lookups must specify the username and password";
1291 return DEFER;
1292 }
1293 if (password[0] == 0)
1294 {
1295 DEBUG(D_lookup) debug_printf("Empty password: ldapauth returns FAIL\n");
1296 return FAIL;
1297 }
1298 }
1299
1300/* Check for valid ldap url starters */
1301
1302p = url + 4;
1303if (tolower(*p) == 's' || tolower(*p) == 'i') p++;
1304if (Ustrncmp(p, "://", 3) != 0)
1305 {
1306 *errmsg = string_sprintf("LDAP URL does not start with \"ldap://\", "
1307 "\"ldaps://\", or \"ldapi://\" (it starts with \"%.16s...\")", url);
1308 DEBUG(D_lookup) debug_printf("LDAP query error: %s\n", *errmsg);
1309 return DEFER;
1310 }
1311
1312/* No default servers, or URL contains a server name: just one attempt */
1313
deae092e 1314if ((eldap_default_servers == NULL && local_servers == NULL) || p[3] != '/')
0756eb3c
PH
1315 {
1316 return perform_ldap_search(url, NULL, 0, search_type, res, errmsg,
6ec97b1b
PH
1317 &defer_break, user, password, sizelimit, timelimit, tcplimit, dereference,
1318 referrals);
0756eb3c
PH
1319 }
1320
deae092e
HS
1321/* Loop through the default servers until OK or FAIL. Use local_servers list
1322 * if defined in the lookup, otherwise use the global default list */
1323list = (local_servers == NULL) ? eldap_default_servers : local_servers;
0756eb3c
PH
1324while ((server = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) != NULL)
1325 {
1326 int rc;
1327 int port = 0;
1328 uschar *colon = Ustrchr(server, ':');
1329 if (colon != NULL)
1330 {
1331 *colon = 0;
1332 port = Uatoi(colon+1);
1333 }
1334 rc = perform_ldap_search(url, server, port, search_type, res, errmsg,
6ec97b1b
PH
1335 &defer_break, user, password, sizelimit, timelimit, tcplimit, dereference,
1336 referrals);
0756eb3c
PH
1337 if (rc != DEFER || defer_break) return rc;
1338 }
1339
1340return DEFER;
1341}
1342
1343
1344
1345/*************************************************
1346* Find entry point *
1347*************************************************/
1348
1349/* See local README for interface description. The different kinds of search
1350are handled by a common function, with a flag to differentiate between them.
1351The handle and filename arguments are not used. */
1352
e6d225ae 1353static int
55414b25 1354eldap_find(void *handle, uschar *filename, const uschar *ldap_url, int length,
14b3c5bc 1355 uschar **result, uschar **errmsg, uint *do_cache)
0756eb3c
PH
1356{
1357/* Keep picky compilers happy */
1358do_cache = do_cache;
1359return(control_ldap_search(ldap_url, SEARCH_LDAP_SINGLE, result, errmsg));
1360}
1361
e6d225ae 1362static int
55414b25 1363eldapm_find(void *handle, uschar *filename, const uschar *ldap_url, int length,
14b3c5bc 1364 uschar **result, uschar **errmsg, uint *do_cache)
0756eb3c
PH
1365{
1366/* Keep picky compilers happy */
1367do_cache = do_cache;
1368return(control_ldap_search(ldap_url, SEARCH_LDAP_MULTIPLE, result, errmsg));
1369}
1370
e6d225ae 1371static int
55414b25 1372eldapdn_find(void *handle, uschar *filename, const uschar *ldap_url, int length,
14b3c5bc 1373 uschar **result, uschar **errmsg, uint *do_cache)
0756eb3c
PH
1374{
1375/* Keep picky compilers happy */
1376do_cache = do_cache;
1377return(control_ldap_search(ldap_url, SEARCH_LDAP_DN, result, errmsg));
1378}
1379
1380int
55414b25 1381eldapauth_find(void *handle, uschar *filename, const uschar *ldap_url, int length,
14b3c5bc 1382 uschar **result, uschar **errmsg, uint *do_cache)
0756eb3c
PH
1383{
1384/* Keep picky compilers happy */
1385do_cache = do_cache;
1386return(control_ldap_search(ldap_url, SEARCH_LDAP_AUTH, result, errmsg));
1387}
1388
1389
1390
1391/*************************************************
1392* Open entry point *
1393*************************************************/
1394
1395/* See local README for interface description. */
1396
e6d225ae 1397static void *
0756eb3c
PH
1398eldap_open(uschar *filename, uschar **errmsg)
1399{
1400return (void *)(1); /* Just return something non-null */
1401}
1402
1403
1404
1405/*************************************************
1406* Tidy entry point *
1407*************************************************/
1408
1409/* See local README for interface description.
1410Make sure that eldap_dn does not refer to reclaimed or worse, freed store */
1411
e6d225ae 1412static void
0756eb3c
PH
1413eldap_tidy(void)
1414{
1415LDAP_CONNECTION *lcp = NULL;
1416eldap_dn = NULL;
1417
1418while ((lcp = ldap_connections) != NULL)
1419 {
1420 DEBUG(D_lookup) debug_printf("unbind LDAP connection to %s:%d\n", lcp->host,
1421 lcp->port);
ff2c417d
TL
1422 if(lcp->bound == TRUE)
1423 ldap_unbind(lcp->ld);
0756eb3c
PH
1424 ldap_connections = lcp->next;
1425 }
1426}
1427
1428
1429
1430/*************************************************
1431* Quote entry point *
1432*************************************************/
1433
1434/* LDAP quoting is unbelievably messy. For a start, two different levels of
1435quoting have to be done: LDAP quoting, and URL quoting. The current
1436specification is the result of a suggestion by Brian Candler. It recognizes
1437two separate cases:
1438
1439(1) For text that appears in a search filter, the following escapes are
1440 required (see RFC 2254):
1441
1442 * -> \2A
1443 ( -> \28
1444 ) -> \29
1445 \ -> \5C
1446 NULL -> \00
1447
1448 Then the entire filter text must be URL-escaped. This kind of quoting is
1449 implemented by ${quote_ldap:....}. Note that we can never have a NULL
1450 in the input string, because that's a terminator.
1451
1452(2) For a DN that is part of a URL (i.e. the base DN), the characters
1453
1454 , + " \ < > ;
1455
1456 must be quoted by backslashing. See RFC 2253. Leading and trailing spaces
1457 must be escaped, as must a leading #. Then the string must be URL-quoted.
1458 This type of quoting is implemented by ${quote_ldap_dn:....}.
1459
1460For URL quoting, the only characters that need not be quoted are the
1461alphamerics and
1462
1463 ! $ ' ( ) * + - . _
1464
1465All the others must be hexified and preceded by %. This includes the
1466backslashes used for LDAP quoting.
1467
1468For a DN that is given in the USER parameter for authentication, we need the
1469same initial quoting as (2) but in this case, the result must NOT be
1470URL-escaped, because it isn't a URL. The way this is handled is by
1471de-URL-quoting the text when processing the USER parameter in
1472control_ldap_search() above. That means that the same quote operator can be
1473used. This has the additional advantage that spaces in the DN won't cause
1474parsing problems. For example:
1475
1476 USER=cn=${quote_ldap_dn:$1},%20dc=example,%20dc=com
1477
1478should be safe if there are spaces in $1.
1479
1480
1481Arguments:
1482 s the string to be quoted
1483 opt additional option text or NULL if none
1484 only "dn" is recognized
1485
1486Returns: the processed string or NULL for a bad option
1487*/
1488
1489
1490
1491/* The characters in this string, together with alphanumerics, never need
1492quoting in any way. */
1493
1494#define ALWAYS_LITERAL "!$'-._"
1495
1496/* The special characters in this string do not need to be URL-quoted. The set
1497is a bit larger than the general literals. */
1498
1499#define URL_NONQUOTE ALWAYS_LITERAL "()*+"
1500
1501/* The following macros define the characters that are quoted by quote_ldap and
1502quote_ldap_dn, respectively. */
1503
1504#define LDAP_QUOTE "*()\\"
1505#define LDAP_DN_QUOTE ",+\"\\<>;"
1506
1507
1508
e6d225ae 1509static uschar *
0756eb3c
PH
1510eldap_quote(uschar *s, uschar *opt)
1511{
1512register int c;
1513int count = 0;
1514int len = 0;
1515BOOL dn = FALSE;
1516uschar *t = s;
1517uschar *quoted;
1518
1519/* Test for a DN quotation. */
1520
1521if (opt != NULL)
1522 {
1523 if (Ustrcmp(opt, "dn") != 0) return NULL; /* No others recognized */
1524 dn = TRUE;
1525 }
1526
1527/* Compute how much extra store we need for the string. This doesn't have to be
1528exact as long as it isn't an underestimate. The worst case is the addition of 5
1529extra bytes for a single character. This occurs for certain characters in DNs,
1530where, for example, < turns into %5C%3C. For simplicity, we just add 5 for each
1531possibly escaped character. The really fast way would be just to test for
1532non-alphanumerics, but it is probably better to spot a few others that are
1533never escaped, because if there are no specials at all, we can avoid copying
1534the string. */
1535
1536while ((c = *t++) != 0)
1537 {
1538 len++;
1539 if (!isalnum(c) && Ustrchr(ALWAYS_LITERAL, c) == NULL) count += 5;
1540 }
1541if (count == 0) return s;
1542
1543/* Get sufficient store to hold the quoted string */
1544
1545t = quoted = store_get(len + count + 1);
1546
1547/* Handle plain quote_ldap */
1548
1549if (!dn)
1550 {
1551 while ((c = *s++) != 0)
1552 {
1553 if (!isalnum(c))
1554 {
1555 if (Ustrchr(LDAP_QUOTE, c) != NULL)
1556 {
1557 sprintf(CS t, "%%5C%02X", c); /* e.g. * => %5C2A */
1558 t += 5;
1559 continue;
1560 }
1561 if (Ustrchr(URL_NONQUOTE, c) == NULL) /* e.g. ] => %5D */
1562 {
1563 sprintf(CS t, "%%%02X", c);
1564 t += 3;
1565 continue;
1566 }
1567 }
1568 *t++ = c; /* unquoted character */
1569 }
1570 }
1571
1572/* Handle quote_ldap_dn */
1573
1574else
1575 {
1576 uschar *ss = s + len;
1577
1578 /* Find the last char before any trailing spaces */
1579
1580 while (ss > s && ss[-1] == ' ') ss--;
1581
1582 /* Quote leading spaces and sharps */
1583
1584 for (; s < ss; s++)
1585 {
1586 if (*s != ' ' && *s != '#') break;
1587 sprintf(CS t, "%%5C%%%02X", *s);
1588 t += 6;
1589 }
1590
1591 /* Handle the rest of the string, up to the trailing spaces */
1592
1593 while (s < ss)
1594 {
1595 c = *s++;
1596 if (!isalnum(c))
1597 {
1598 if (Ustrchr(LDAP_DN_QUOTE, c) != NULL)
1599 {
1600 Ustrncpy(t, "%5C", 3); /* insert \ where needed */
1601 t += 3; /* fall through to check URL */
1602 }
1603 if (Ustrchr(URL_NONQUOTE, c) == NULL) /* e.g. ] => %5D */
1604 {
1605 sprintf(CS t, "%%%02X", c);
1606 t += 3;
1607 continue;
1608 }
1609 }
1610 *t++ = c; /* unquoted character, or non-URL quoted after %5C */
1611 }
1612
1613 /* Handle the trailing spaces */
1614
1615 while (*ss++ != 0)
1616 {
1617 Ustrncpy(t, "%5C%20", 6);
1618 t += 6;
1619 }
1620 }
1621
1622/* Terminate the new string and return */
1623
1624*t = 0;
1625return quoted;
1626}
1627
6545de78
PP
1628
1629
1630/*************************************************
1631* Version reporting entry point *
1632*************************************************/
1633
1634/* See local README for interface description. */
1635
1636#include "../version.h"
1637
1638void
1639ldap_version_report(FILE *f)
1640{
1641#ifdef DYNLOOKUP
1642fprintf(f, "Library version: LDAP: Exim version %s\n", EXIM_VERSION_STR);
1643#endif
1644}
1645
1646
e6d225ae
DW
1647static lookup_info ldap_lookup_info = {
1648 US"ldap", /* lookup name */
1649 lookup_querystyle, /* query-style lookup */
1650 eldap_open, /* open function */
1651 NULL, /* check function */
1652 eldap_find, /* find function */
1653 NULL, /* no close function */
1654 eldap_tidy, /* tidy function */
6545de78
PP
1655 eldap_quote, /* quoting function */
1656 ldap_version_report /* version reporting */
e6d225ae
DW
1657};
1658
1659static lookup_info ldapdn_lookup_info = {
1660 US"ldapdn", /* lookup name */
1661 lookup_querystyle, /* query-style lookup */
1662 eldap_open, /* sic */ /* open function */
1663 NULL, /* check function */
1664 eldapdn_find, /* find function */
1665 NULL, /* no close function */
1666 eldap_tidy, /* sic */ /* tidy function */
6545de78
PP
1667 eldap_quote, /* sic */ /* quoting function */
1668 NULL /* no version reporting (redundant) */
e6d225ae
DW
1669};
1670
1671static lookup_info ldapm_lookup_info = {
1672 US"ldapm", /* lookup name */
1673 lookup_querystyle, /* query-style lookup */
1674 eldap_open, /* sic */ /* open function */
1675 NULL, /* check function */
1676 eldapm_find, /* find function */
1677 NULL, /* no close function */
1678 eldap_tidy, /* sic */ /* tidy function */
6545de78
PP
1679 eldap_quote, /* sic */ /* quoting function */
1680 NULL /* no version reporting (redundant) */
e6d225ae
DW
1681};
1682
1683#ifdef DYNLOOKUP
1684#define ldap_lookup_module_info _lookup_module_info
1685#endif
1686
1687static lookup_info *_lookup_list[] = { &ldap_lookup_info, &ldapdn_lookup_info, &ldapm_lookup_info };
1688lookup_module_info ldap_lookup_module_info = { LOOKUP_MODULE_INFO_MAGIC, _lookup_list, 3 };
0756eb3c
PH
1689
1690/* End of lookups/ldap.c */