document TK's bug 1239 fix in ChangeLog
[exim.git] / src / src / lookups / ldap.c
CommitLineData
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1/*************************************************
2* Exim - an Internet mail transport agent *
3*************************************************/
4
0a49a7a4 5/* Copyright (c) University of Cambridge 1995 - 2009 */
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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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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
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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;
84 LDAP *ld;
85} LDAP_CONNECTION;
86
87static LDAP_CONNECTION *ldap_connections = NULL;
88
89
90
91/*************************************************
92* Internal search function *
93*************************************************/
94
95/* This is the function that actually does the work. It is called (indirectly
96via control_ldap_search) from eldap_find(), eldapauth_find(), eldapdn_find(),
97and eldapm_find(), with a difference in the "search_type" argument.
98
99The case of eldapauth_find() is special in that all it does is do
100authentication, returning OK or FAIL as appropriate. This isn't used as a
101lookup. Instead, it is called from expand.c as an expansion condition test.
102
103The DN from a successful lookup is placed in $ldap_dn. This feature postdates
104the provision of the SEARCH_LDAP_DN facility for returning just the DN as the
105data.
106
107Arguments:
108 ldap_url the URL to be looked up
109 server server host name, when URL contains none
110 s_port server port, used when URL contains no name
111 search_type SEARCH_LDAP_MULTIPLE allows values from multiple entries
112 SEARCH_LDAP_SINGLE allows values from one entry only
113 SEARCH_LDAP_DN gets the DN from one entry
114 res set to point at the result (not used for ldapauth)
115 errmsg set to point a message if result is not OK
116 defer_break set TRUE if no more servers to be tried after a DEFER
117 user user name for authentication, or NULL
118 password password for authentication, or NULL
119 sizelimit max number of entries returned, or 0 for no limit
120 timelimit max time to wait, or 0 for no limit
d00328e2 121 tcplimit max time for network activity, e.g. connect, or 0 for OS default
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122 deference the dereference option, which is one of
123 LDAP_DEREF_{NEVER,SEARCHING,FINDING,ALWAYS}
6ec97b1b 124 referrals the referral option, which is LDAP_OPT_ON or LDAP_OPT_OFF
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125
126Returns: OK or FAIL or DEFER
127 FAIL is given only if a lookup was performed successfully, but
128 returned no data.
129*/
130
131static int
132perform_ldap_search(uschar *ldap_url, uschar *server, int s_port, int search_type,
133 uschar **res, uschar **errmsg, BOOL *defer_break, uschar *user, uschar *password,
6ec97b1b 134 int sizelimit, int timelimit, int tcplimit, int dereference, void *referrals)
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PH
135{
136LDAPURLDesc *ludp = NULL;
137LDAPMessage *result = NULL;
138BerElement *ber;
139LDAP_CONNECTION *lcp;
140
141struct timeval timeout;
142struct timeval *timeoutptr = NULL;
143
144uschar *attr;
145uschar **attrp;
146uschar *data = NULL;
147uschar *dn = NULL;
148uschar *host;
149uschar **values;
150uschar **firstval;
151uschar porttext[16];
152
153uschar *error1 = NULL; /* string representation of errcode (static) */
154uschar *error2 = NULL; /* error message from the server */
155uschar *matched = NULL; /* partially matched DN */
156
157int attr_count = 0;
158int error_yield = DEFER;
159int msgid;
d38f8232 160int rc, ldap_rc, ldap_parse_rc;
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161int port;
162int ptr = 0;
163int rescount = 0;
164int size = 0;
165BOOL attribute_found = FALSE;
166BOOL ldapi = FALSE;
167
168DEBUG(D_lookup)
169 debug_printf("perform_ldap_search: ldap%s URL = \"%s\" server=%s port=%d "
170 "sizelimit=%d timelimit=%d tcplimit=%d\n",
171 (search_type == SEARCH_LDAP_MULTIPLE)? "m" :
172 (search_type == SEARCH_LDAP_DN)? "dn" :
173 (search_type == SEARCH_LDAP_AUTH)? "auth" : "",
174 ldap_url, server, s_port, sizelimit, timelimit, tcplimit);
175
176/* Check if LDAP thinks the URL is a valid LDAP URL. We assume that if the LDAP
177library that is in use doesn't recognize, say, "ldapi", it will barf here. */
178
179if (!ldap_is_ldap_url(CS ldap_url))
180 {
181 *errmsg = string_sprintf("ldap_is_ldap_url: not an LDAP url \"%s\"\n",
182 ldap_url);
183 goto RETURN_ERROR_BREAK;
184 }
185
186/* Parse the URL */
187
188if ((rc = ldap_url_parse(CS ldap_url, &ludp)) != 0)
189 {
190 *errmsg = string_sprintf("ldap_url_parse: (error %d) parsing \"%s\"\n", rc,
191 ldap_url);
192 goto RETURN_ERROR_BREAK;
193 }
194
195/* If the host name is empty, take it from the separate argument, if one is
196given. OpenLDAP 2.0.6 sets an unset hostname to "" rather than empty, but
197expects NULL later in ldap_init() to mean "default", annoyingly. In OpenLDAP
1982.0.11 this has changed (it uses NULL). */
199
200if ((ludp->lud_host == NULL || ludp->lud_host[0] == 0) && server != NULL)
201 {
202 host = server;
203 port = s_port;
204 }
205else
206 {
207 host = US ludp->lud_host;
208 if (host != NULL && host[0] == 0) host = NULL;
209 port = ludp->lud_port;
210 }
211
212DEBUG(D_lookup) debug_printf("after ldap_url_parse: host=%s port=%d\n",
213 host, port);
214
215if (port == 0) port = LDAP_PORT; /* Default if none given */
216sprintf(CS porttext, ":%d", port); /* For messages */
217
218/* If the "host name" is actually a path, we are going to connect using a Unix
219socket, regardless of whether "ldapi" was actually specified or not. This means
220that a Unix socket can be declared in eldap_default_servers, and "traditional"
221LDAP queries using just "ldap" can be used ("ldaps" is similarly overridden).
222The path may start with "/" or it may already be escaped as "%2F" if it was
223actually declared that way in eldap_default_servers. (I did it that way the
224first time.) If the host name is not a path, the use of "ldapi" causes an
225error, except in the default case. (But lud_scheme doesn't seem to exist in
226older libraries.) */
227
228if (host != NULL)
229 {
230 if ((host[0] == '/' || Ustrncmp(host, "%2F", 3) == 0))
231 {
232 ldapi = TRUE;
233 porttext[0] = 0; /* Remove port from messages */
234 }
235
236 #if defined LDAP_LIB_OPENLDAP2
237 else if (strncmp(ludp->lud_scheme, "ldapi", 5) == 0)
238 {
239 *errmsg = string_sprintf("ldapi requires an absolute path (\"%s\" given)",
240 host);
241 goto RETURN_ERROR;
242 }
243 #endif
244 }
245
246/* Count the attributes; we need this later to tell us how to format results */
247
248for (attrp = USS ludp->lud_attrs; attrp != NULL && *attrp != NULL; attrp++)
249 attr_count++;
250
251/* See if we can find a cached connection to this host. The port is not
252relevant for ldapi. The host name pointer is set to NULL if no host was given
253(implying the library default), rather than to the empty string. Note that in
254this case, there is no difference between ldap and ldapi. */
255
256for (lcp = ldap_connections; lcp != NULL; lcp = lcp->next)
257 {
258 if ((host == NULL) != (lcp->host == NULL) ||
259 (host != NULL && strcmpic(lcp->host, host) != 0))
260 continue;
261 if (ldapi || port == lcp->port) break;
262 }
263
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264/* Use this network timeout in any requests. */
265
266if (tcplimit > 0)
267 {
268 timeout.tv_sec = tcplimit;
269 timeout.tv_usec = 0;
270 timeoutptr = &timeout;
271 }
272
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273/* If no cached connection found, we must open a connection to the server. If
274the server name is actually an absolute path, we set ldapi=TRUE above. This
275requests connection via a Unix socket. However, as far as I know, only OpenLDAP
276supports the use of sockets, and the use of ldap_initialize(). */
277
278if (lcp == NULL)
279 {
280 LDAP *ld;
281
282
283 /* --------------------------- OpenLDAP ------------------------ */
284
285 /* There seems to be a preference under OpenLDAP for ldap_initialize()
286 instead of ldap_init(), though I have as yet been unable to find
287 documentation that says this. (OpenLDAP documentation is sparse to
288 non-existent). So we handle OpenLDAP differently here. Also, support for
289 ldapi seems to be OpenLDAP-only at present. */
290
291 #ifdef LDAP_LIB_OPENLDAP2
292
293 /* We now need an empty string for the default host. Get some store in which
294 to build a URL for ldap_initialize(). In the ldapi case, it can't be bigger
295 than (9 + 3*Ustrlen(shost)), whereas in the other cases it can't be bigger
296 than the host name + "ldaps:///" plus : and a port number, say 20 + the
297 length of the host name. What we get should accommodate both, easily. */
298
299 uschar *shost = (host == NULL)? US"" : host;
300 uschar *init_url = store_get(20 + 3 * Ustrlen(shost));
301 uschar *init_ptr;
302
303 /* Handle connection via Unix socket ("ldapi"). We build a basic LDAP URI to
304 contain the path name, with slashes escaped as %2F. */
305
306 if (ldapi)
307 {
308 int ch;
309 init_ptr = init_url + 8;
310 Ustrcpy(init_url, "ldapi://");
311 while ((ch = *shost++) != 0)
312 {
313 if (ch == '/')
314 {
315 Ustrncpy(init_ptr, "%2F", 3);
316 init_ptr += 3;
317 }
318 else *init_ptr++ = ch;
319 }
320 *init_ptr = 0;
321 }
322
323 /* This is not an ldapi call. Just build a URI with the protocol type, host
324 name, and port. */
325
326 else
327 {
328 init_ptr = Ustrchr(ldap_url, '/');
329 Ustrncpy(init_url, ldap_url, init_ptr - ldap_url);
330 init_ptr = init_url + (init_ptr - ldap_url);
331 sprintf(CS init_ptr, "//%s:%d/", shost, port);
332 }
333
334 /* Call ldap_initialize() and check the result */
335
336 DEBUG(D_lookup) debug_printf("ldap_initialize with URL %s\n", init_url);
337 rc = ldap_initialize(&ld, CS init_url);
338 if (rc != LDAP_SUCCESS)
339 {
340 *errmsg = string_sprintf("ldap_initialize: (error %d) URL \"%s\"\n",
341 rc, init_url);
342 goto RETURN_ERROR;
343 }
344 store_reset(init_url); /* Might as well save memory when we can */
345
346
347 /* ------------------------- Not OpenLDAP ---------------------- */
348
349 /* For libraries other than OpenLDAP, use ldap_init(). */
350
351 #else /* LDAP_LIB_OPENLDAP2 */
352 ld = ldap_init(CS host, port);
353 #endif /* LDAP_LIB_OPENLDAP2 */
354
355 /* -------------------------------------------------------------- */
356
357
358 /* Handle failure to initialize */
359
360 if (ld == NULL)
361 {
362 *errmsg = string_sprintf("failed to initialize for LDAP server %s%s - %s",
363 host, porttext, strerror(errno));
364 goto RETURN_ERROR;
365 }
366
367 /* Set the TCP connect time limit if available. This is something that is
368 in Netscape SDK v4.1; I don't know about other libraries. */
369
370 #ifdef LDAP_X_OPT_CONNECT_TIMEOUT
7c7ad977
PH
371 if (tcplimit > 0)
372 {
994a09e9 373 int timeout1000 = tcplimit*1000;
7c7ad977
PH
374 ldap_set_option(ld, LDAP_X_OPT_CONNECT_TIMEOUT, (void *)&timeout1000);
375 }
994a09e9
PH
376 else
377 {
378 int notimeout = LDAP_X_IO_TIMEOUT_NO_TIMEOUT;
379 ldap_set_option(ld, LDAP_X_OPT_CONNECT_TIMEOUT, (void *)&notimeout);
380 }
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381 #endif
382
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383 /* Set the TCP connect timeout. This works with OpenLDAP 2.2.14. */
384
385 #ifdef LDAP_OPT_NETWORK_TIMEOUT
386 if (tcplimit > 0)
387 ldap_set_option(ld, LDAP_OPT_NETWORK_TIMEOUT, (void *)timeoutptr);
8e669ac1 388 #endif
7c7ad977 389
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390 /* I could not get TLS to work until I set the version to 3. That version
391 seems to be the default nowadays. The RFC is dated 1997, so I would hope
392 that all the LDAP libraries support it. Therefore, if eldap_version hasn't
393 been set, go for v3 if we can. */
394
395 if (eldap_version < 0)
396 {
397 #ifdef LDAP_VERSION3
398 eldap_version = LDAP_VERSION3;
399 #else
400 eldap_version = 2;
401 #endif
402 }
403
404 #ifdef LDAP_OPT_PROTOCOL_VERSION
405 ldap_set_option(ld, LDAP_OPT_PROTOCOL_VERSION, (void *)&eldap_version);
406 #endif
407
408 DEBUG(D_lookup) debug_printf("initialized for LDAP (v%d) server %s%s\n",
409 eldap_version, host, porttext);
410
411 /* If not using ldapi and TLS is available, set appropriate TLS options: hard
412 for "ldaps" and soft otherwise. */
413
414 #ifdef LDAP_OPT_X_TLS
415 if (!ldapi)
416 {
417 int tls_option;
418 if (strncmp(ludp->lud_scheme, "ldaps", 5) == 0)
419 {
420 tls_option = LDAP_OPT_X_TLS_HARD;
421 DEBUG(D_lookup) debug_printf("LDAP_OPT_X_TLS_HARD set\n");
422 }
423 else
424 {
425 tls_option = LDAP_OPT_X_TLS_TRY;
426 DEBUG(D_lookup) debug_printf("LDAP_OPT_X_TLS_TRY set\n");
427 }
428 ldap_set_option(ld, LDAP_OPT_X_TLS, (void *)&tls_option);
429 }
430 #endif /* LDAP_OPT_X_TLS */
431
bc19a55b
PP
432 #ifdef LDAP_OPT_X_TLS_CACERTFILE
433 if (eldap_ca_cert_file != NULL)
434 {
435 ldap_set_option(ld, LDAP_OPT_X_TLS_CACERTFILE, eldap_ca_cert_file);
436 }
437 #endif
438 #ifdef LDAP_OPT_X_TLS_CACERTDIR
439 if (eldap_ca_cert_dir != NULL)
440 {
441 ldap_set_option(ld, LDAP_OPT_X_TLS_CACERTDIR, eldap_ca_cert_dir);
442 }
443 #endif
444 #ifdef LDAP_OPT_X_TLS_CERTFILE
445 if (eldap_cert_file != NULL)
446 {
447 ldap_set_option(ld, LDAP_OPT_X_TLS_CERTFILE, eldap_cert_file);
448 }
449 #endif
450 #ifdef LDAP_OPT_X_TLS_KEYFILE
451 if (eldap_cert_key != NULL)
452 {
453 ldap_set_option(ld, LDAP_OPT_X_TLS_KEYFILE, eldap_cert_key);
454 }
455 #endif
456 #ifdef LDAP_OPT_X_TLS_CIPHER_SUITE
457 if (eldap_cipher_suite != NULL)
458 {
459 ldap_set_option(ld, LDAP_OPT_X_TLS_CIPHER_SUITE, eldap_cipher_suite);
460 }
461 #endif
462 #ifdef LDAP_OPT_X_TLS_REQUIRE_CERT
463 if (eldap_require_cert != NULL)
464 {
465 int cert_option = LDAP_OPT_X_TLS_NEVER;
466 if (Ustrcmp(eldap_require_cert, "hard") == 0)
467 {
468 cert_option = LDAP_OPT_X_TLS_HARD;
469 }
470 else if (Ustrcmp(eldap_require_cert, "demand") == 0)
471 {
472 cert_option = LDAP_OPT_X_TLS_DEMAND;
473 }
474 else if (Ustrcmp(eldap_require_cert, "allow") == 0)
475 {
476 cert_option = LDAP_OPT_X_TLS_ALLOW;
477 }
478 else if (Ustrcmp(eldap_require_cert, "try") == 0)
479 {
480 cert_option = LDAP_OPT_X_TLS_TRY;
481 }
10906672 482 ldap_set_option(ld, LDAP_OPT_X_TLS_REQUIRE_CERT, &cert_option);
bc19a55b
PP
483 }
484 #endif
485
0756eb3c
PH
486 /* Now add this connection to the chain of cached connections */
487
488 lcp = store_get(sizeof(LDAP_CONNECTION));
489 lcp->host = (host == NULL)? NULL : string_copy(host);
490 lcp->bound = FALSE;
491 lcp->user = NULL;
492 lcp->password = NULL;
493 lcp->port = port;
494 lcp->ld = ld;
495 lcp->next = ldap_connections;
496 ldap_connections = lcp;
497 }
498
499/* Found cached connection */
500
501else
502 {
503 DEBUG(D_lookup)
504 debug_printf("re-using cached connection to LDAP server %s%s\n",
505 host, porttext);
506 }
507
508/* Bind with the user/password supplied, or an anonymous bind if these values
509are NULL, unless a cached connection is already bound with the same values. */
510
511if (!lcp->bound ||
512 (lcp->user == NULL && user != NULL) ||
513 (lcp->user != NULL && user == NULL) ||
514 (lcp->user != NULL && user != NULL && Ustrcmp(lcp->user, user) != 0) ||
515 (lcp->password == NULL && password != NULL) ||
516 (lcp->password != NULL && password == NULL) ||
517 (lcp->password != NULL && password != NULL &&
518 Ustrcmp(lcp->password, password) != 0))
519 {
520 DEBUG(D_lookup) debug_printf("%sbinding with user=%s password=%s\n",
521 (lcp->bound)? "re-" : "", user, password);
867fcbf5
PP
522#ifdef LDAP_OPT_X_TLS
523 /* The Oracle LDAP libraries (LDAP_LIB_TYPE=SOLARIS) don't support this: */
bc19a55b
PP
524 if (eldap_start_tls)
525 {
526 ldap_start_tls_s(lcp->ld, NULL, NULL);
527 }
867fcbf5 528#endif
7c7ad977
PH
529 if ((msgid = ldap_bind(lcp->ld, CS user, CS password, LDAP_AUTH_SIMPLE))
530 == -1)
0756eb3c 531 {
7c7ad977 532 *errmsg = string_sprintf("failed to bind the LDAP connection to server "
d00328e2 533 "%s%s - ldap_bind() returned -1", host, porttext);
7c7ad977
PH
534 goto RETURN_ERROR;
535 }
0756eb3c 536
7c7ad977
PH
537 if ((rc = ldap_result( lcp->ld, msgid, 1, timeoutptr, &result )) <= 0)
538 {
539 *errmsg = string_sprintf("failed to bind the LDAP connection to server "
8e669ac1 540 "%s%s - LDAP error: %s", host, porttext,
7c7ad977
PH
541 rc == -1 ? "result retrieval failed" : "timeout" );
542 result = NULL;
543 goto RETURN_ERROR;
544 }
545
546 rc = ldap_result2error( lcp->ld, result, 0 );
547
548 /* Invalid credentials when just checking credentials returns FAIL. This
549 stops any further servers being tried. */
0756eb3c 550
7c7ad977
PH
551 if (search_type == SEARCH_LDAP_AUTH && rc == LDAP_INVALID_CREDENTIALS)
552 {
553 DEBUG(D_lookup)
554 debug_printf("Invalid credentials: ldapauth returns FAIL\n");
555 error_yield = FAIL;
556 goto RETURN_ERROR_NOMSG;
557 }
0756eb3c 558
7c7ad977
PH
559 /* Otherwise we have a problem that doesn't stop further servers from being
560 tried. */
561
562 if (rc != LDAP_SUCCESS)
563 {
0756eb3c
PH
564 *errmsg = string_sprintf("failed to bind the LDAP connection to server "
565 "%s%s - LDAP error %d: %s", host, porttext, rc, ldap_err2string(rc));
566 goto RETURN_ERROR;
567 }
568
569 /* Successful bind */
570
571 lcp->bound = TRUE;
572 lcp->user = (user == NULL)? NULL : string_copy(user);
573 lcp->password = (password == NULL)? NULL : string_copy(password);
7c7ad977
PH
574
575 ldap_msgfree(result);
576 result = NULL;
0756eb3c
PH
577 }
578
579/* If we are just checking credentials, return OK. */
580
581if (search_type == SEARCH_LDAP_AUTH)
582 {
583 DEBUG(D_lookup) debug_printf("Bind succeeded: ldapauth returns OK\n");
584 goto RETURN_OK;
585 }
586
587/* Before doing the search, set the time and size limits (if given). Here again
588the different implementations of LDAP have chosen to do things differently. */
589
590#if defined(LDAP_OPT_SIZELIMIT)
591ldap_set_option(lcp->ld, LDAP_OPT_SIZELIMIT, (void *)&sizelimit);
592ldap_set_option(lcp->ld, LDAP_OPT_TIMELIMIT, (void *)&timelimit);
593#else
594lcp->ld->ld_sizelimit = sizelimit;
595lcp->ld->ld_timelimit = timelimit;
596#endif
597
598/* Similarly for dereferencing aliases. Don't know if this is possible on
599an LDAP library without LDAP_OPT_DEREF. */
600
601#if defined(LDAP_OPT_DEREF)
602ldap_set_option(lcp->ld, LDAP_OPT_DEREF, (void *)&dereference);
603#endif
604
6ec97b1b
PH
605/* Similarly for the referral setting; should the library follow referrals that
606the LDAP server returns? The conditional is just in case someone uses a library
607without it. */
608
609#if defined(LDAP_OPT_REFERRALS)
610ldap_set_option(lcp->ld, LDAP_OPT_REFERRALS, referrals);
611#endif
612
0756eb3c
PH
613/* Start the search on the server. */
614
615DEBUG(D_lookup) debug_printf("Start search\n");
616
617msgid = ldap_search(lcp->ld, ludp->lud_dn, ludp->lud_scope, ludp->lud_filter,
618 ludp->lud_attrs, 0);
619
620if (msgid == -1)
621 {
3ca0ba97
PH
622 #if defined LDAP_LIB_SOLARIS || defined LDAP_LIB_OPENLDAP2
623 int err;
624 ldap_get_option(lcp->ld, LDAP_OPT_ERROR_NUMBER, &err);
8e669ac1 625 *errmsg = string_sprintf("ldap_search failed: %d, %s", err,
3ca0ba97 626 ldap_err2string(err));
8e669ac1
PH
627
628 #else
3ca0ba97
PH
629 *errmsg = string_sprintf("ldap_search failed");
630 #endif
8e669ac1 631
0756eb3c
PH
632 goto RETURN_ERROR;
633 }
634
635/* Loop to pick up results as they come in, setting a timeout if one was
636given. */
637
0756eb3c
PH
638while ((rc = ldap_result(lcp->ld, msgid, 0, timeoutptr, &result)) ==
639 LDAP_RES_SEARCH_ENTRY)
640 {
641 LDAPMessage *e;
642
643 DEBUG(D_lookup) debug_printf("ldap_result loop\n");
644
645 for(e = ldap_first_entry(lcp->ld, result);
646 e != NULL;
647 e = ldap_next_entry(lcp->ld, e))
648 {
649 uschar *new_dn;
650 BOOL insert_space = FALSE;
651
652 DEBUG(D_lookup) debug_printf("LDAP entry loop\n");
653
654 rescount++; /* Count results */
655
656 /* Results for multiple entries values are separated by newlines. */
657
658 if (data != NULL) data = string_cat(data, &size, &ptr, US"\n", 1);
659
660 /* Get the DN from the last result. */
661
662 new_dn = US ldap_get_dn(lcp->ld, e);
663 if (new_dn != NULL)
664 {
665 if (dn != NULL)
666 {
667 #if defined LDAP_LIB_NETSCAPE || defined LDAP_LIB_OPENLDAP2
668 ldap_memfree(dn);
669 #else /* OPENLDAP 1, UMich, Solaris */
670 free(dn);
671 #endif
672 }
673 /* Save for later */
674 dn = new_dn;
675 }
676
677 /* If the data we want is actually the DN rather than any attribute values,
678 (an "ldapdn" search) add it to the data string. If there are multiple
679 entries, the DNs will be concatenated, but we test for this case below, as
680 for SEARCH_LDAP_SINGLE, and give an error. */
681
682 if (search_type == SEARCH_LDAP_DN) /* Do not amalgamate these into one */
683 { /* condition, because of the else */
684 if (new_dn != NULL) /* below, that's for the first only */
685 {
686 data = string_cat(data, &size, &ptr, new_dn, Ustrlen(new_dn));
687 data[ptr] = 0;
688 attribute_found = TRUE;
689 }
690 }
691
692 /* Otherwise, loop through the entry, grabbing attribute values. If there's
693 only one attribute being retrieved, no attribute name is given, and the
694 result is not quoted. Multiple values are separated by (comma, space).
695 If more than one attribute is being retrieved, the data is given as a
696 sequence of name=value pairs, with the value always in quotes. If there are
697 multiple values, they are given within the quotes, comma separated. */
698
699 else for (attr = US ldap_first_attribute(lcp->ld, e, &ber);
700 attr != NULL;
701 attr = US ldap_next_attribute(lcp->ld, e, ber))
702 {
703 if (attr[0] != 0)
704 {
705 /* Get array of values for this attribute. */
706
707 if ((firstval = values = USS ldap_get_values(lcp->ld, e, CS attr))
708 != NULL)
709 {
710 if (attr_count != 1)
711 {
712 if (insert_space)
713 data = string_cat(data, &size, &ptr, US" ", 1);
714 else
715 insert_space = TRUE;
716 data = string_cat(data, &size, &ptr, attr, Ustrlen(attr));
717 data = string_cat(data, &size, &ptr, US"=\"", 2);
718 }
719
720 while (*values != NULL)
721 {
722 uschar *value = *values;
723 int len = Ustrlen(value);
724
725 DEBUG(D_lookup) debug_printf("LDAP attr loop %s:%s\n", attr, value);
726
727 if (values != firstval)
728 data = string_cat(data, &size, &ptr, US", ", 2);
729
730 /* For multiple attributes, the data is in quotes. We must escape
731 internal quotes, backslashes, newlines. */
732
733 if (attr_count != 1)
734 {
735 int j;
736 for (j = 0; j < len; j++)
737 {
738 if (value[j] == '\n')
739 data = string_cat(data, &size, &ptr, US"\\n", 2);
740 else
741 {
742 if (value[j] == '\"' || value[j] == '\\')
743 data = string_cat(data, &size, &ptr, US"\\", 1);
744 data = string_cat(data, &size, &ptr, value+j, 1);
745 }
746 }
747 }
748
749 /* For single attributes, copy the value verbatim */
750
751 else data = string_cat(data, &size, &ptr, value, len);
752
753 /* Move on to the next value */
754
755 values++;
756 attribute_found = TRUE;
757 }
758
759 /* Closing quote at the end of the data for a named attribute. */
760
761 if (attr_count != 1)
762 data = string_cat(data, &size, &ptr, US"\"", 1);
763
764 /* Free the values */
765
766 ldap_value_free(CSS firstval);
767 }
768 }
769
770 #if defined LDAP_LIB_NETSCAPE || defined LDAP_LIB_OPENLDAP2
771
772 /* Netscape and OpenLDAP2 LDAP's attrs are dynamically allocated and need
773 to be freed. UMich LDAP stores them in static storage and does not require
774 this. */
775
776 ldap_memfree(attr);
777 #endif
778 } /* End "for" loop for extracting attributes from an entry */
779 } /* End "for" loop for extracting entries from a result */
780
781 /* Free the result */
782
783 ldap_msgfree(result);
784 result = NULL;
785 } /* End "while" loop for multiple results */
786
787/* Terminate the dynamic string that we have built and reclaim unused store */
788
789if (data != NULL)
790 {
791 data[ptr] = 0;
792 store_reset(data + ptr + 1);
793 }
794
795/* Copy the last dn into eldap_dn */
796
797if (dn != NULL)
798 {
799 eldap_dn = string_copy(dn);
800 #if defined LDAP_LIB_NETSCAPE || defined LDAP_LIB_OPENLDAP2
801 ldap_memfree(dn);
802 #else /* OPENLDAP 1, UMich, Solaris */
803 free(dn);
804 #endif
805 }
806
807DEBUG(D_lookup) debug_printf("search ended by ldap_result yielding %d\n",rc);
808
809if (rc == 0)
810 {
811 *errmsg = US"ldap_result timed out";
812 goto RETURN_ERROR;
813 }
814
815/* A return code of -1 seems to mean "ldap_result failed internally or couldn't
816provide you with a message". Other error states seem to exist where
817ldap_result() didn't give us any message from the server at all, leaving result
818set to NULL. Apparently, "the error parameters of the LDAP session handle will
819be set accordingly". That's the best we can do to retrieve an error status; we
820can't use functions like ldap_result2error because they parse a message from
821the server, which we didn't get.
822
823Annoyingly, the different implementations of LDAP have gone for different
824methods of handling error codes and generating error messages. */
825
826if (rc == -1 || result == NULL)
827 {
828 int err;
829 DEBUG(D_lookup) debug_printf("ldap_result failed\n");
830
831 #if defined LDAP_LIB_SOLARIS || defined LDAP_LIB_OPENLDAP2
832 ldap_get_option(lcp->ld, LDAP_OPT_ERROR_NUMBER, &err);
833 *errmsg = string_sprintf("ldap_result failed: %d, %s",
834 err, ldap_err2string(err));
835
836 #elif defined LDAP_LIB_NETSCAPE
837 /* Dubious (surely 'matched' is spurious here?) */
838 (void)ldap_get_lderrno(lcp->ld, &matched, &error1);
839 *errmsg = string_sprintf("ldap_result failed: %s (%s)", error1, matched);
840
841 #else /* UMich LDAP aka OpenLDAP 1.x */
842 *errmsg = string_sprintf("ldap_result failed: %d, %s",
843 lcp->ld->ld_errno, ldap_err2string(lcp->ld->ld_errno));
844 #endif
845
846 goto RETURN_ERROR;
847 }
848
849/* A return code that isn't -1 doesn't necessarily mean there were no problems
8e669ac1
PH
850with the search. The message must be an LDAP_RES_SEARCH_RESULT or
851LDAP_RES_SEARCH_REFERENCE or else it's something we can't handle. Some versions
852of LDAP do not define LDAP_RES_SEARCH_REFERENCE (LDAP v1 is one, it seems). So
3295e65b
PH
853we don't provide that functionality when we can't. :-) */
854
8e669ac1 855if (rc != LDAP_RES_SEARCH_RESULT
3295e65b
PH
856#ifdef LDAP_RES_SEARCH_REFERENCE
857 && rc != LDAP_RES_SEARCH_REFERENCE
8e669ac1 858#endif
3295e65b 859 )
0756eb3c
PH
860 {
861 *errmsg = string_sprintf("ldap_result returned unexpected code %d", rc);
862 goto RETURN_ERROR;
863 }
864
865/* We have a result message from the server. This doesn't yet mean all is well.
866We need to parse the message to find out exactly what's happened. */
867
d38f8232
PH
868#if defined LDAP_LIB_SOLARIS || defined LDAP_LIB_OPENLDAP2
869 ldap_rc = rc;
8e669ac1 870 ldap_parse_rc = ldap_parse_result(lcp->ld, result, &rc, CSS &matched,
d38f8232
PH
871 CSS &error2, NULL, NULL, 0);
872 DEBUG(D_lookup) debug_printf("ldap_parse_result: %d\n", ldap_parse_rc);
8e669ac1 873 if (ldap_parse_rc < 0 &&
3295e65b 874 (ldap_parse_rc != LDAP_NO_RESULTS_RETURNED
8e669ac1 875 #ifdef LDAP_RES_SEARCH_REFERENCE
3295e65b 876 || ldap_rc != LDAP_RES_SEARCH_REFERENCE
8e669ac1 877 #endif
3295e65b 878 ))
0756eb3c 879 {
d38f8232 880 *errmsg = string_sprintf("ldap_parse_result failed %d", ldap_parse_rc);
0756eb3c
PH
881 goto RETURN_ERROR;
882 }
883 error1 = US ldap_err2string(rc);
884
885#elif defined LDAP_LIB_NETSCAPE
886 /* Dubious (it doesn't reference 'result' at all!) */
887 rc = ldap_get_lderrno(lcp->ld, &matched, &error1);
888
889#else /* UMich LDAP aka OpenLDAP 1.x */
890 rc = ldap_result2error(lcp->ld, result, 0);
891 error1 = ldap_err2string(rc);
892 error2 = lcp->ld->ld_error;
893 matched = lcp->ld->ld_matched;
894#endif
895
896/* Process the status as follows:
897
898 (1) If we get LDAP_SIZELIMIT_EXCEEDED, just carry on, to return the
899 truncated result list.
900
21eb6e72
PH
901 (2) If we get LDAP_RES_SEARCH_REFERENCE, also just carry on. This was a
902 submitted patch that is reported to "do the right thing" with Solaris
903 LDAP libraries. (The problem it addresses apparently does not occur with
904 Open LDAP.)
905
906 (3) The range of errors defined by LDAP_NAME_ERROR generally mean "that
0756eb3c
PH
907 object does not, or cannot, exist in the database". For those cases we
908 fail the lookup.
909
21eb6e72 910 (4) All other non-successes here are treated as some kind of problem with
0756eb3c
PH
911 the lookup, so return DEFER (which is the default in error_yield).
912*/
913
914DEBUG(D_lookup) debug_printf("ldap_parse_result yielded %d: %s\n",
915 rc, ldap_err2string(rc));
916
21eb6e72
PH
917if (rc != LDAP_SUCCESS && rc != LDAP_SIZELIMIT_EXCEEDED
918 #ifdef LDAP_RES_SEARCH_REFERENCE
919 && rc != LDAP_RES_SEARCH_REFERENCE
920 #endif
921 )
0756eb3c
PH
922 {
923 *errmsg = string_sprintf("LDAP search failed - error %d: %s%s%s%s%s",
924 rc,
925 (error1 != NULL)? error1 : US"",
926 (error2 != NULL && error2[0] != 0)? US"/" : US"",
927 (error2 != NULL)? error2 : US"",
928 (matched != NULL && matched[0] != 0)? US"/" : US"",
929 (matched != NULL)? matched : US"");
930
931 #if defined LDAP_NAME_ERROR
932 if (LDAP_NAME_ERROR(rc))
933 #elif defined NAME_ERROR /* OPENLDAP1 calls it this */
934 if (NAME_ERROR(rc))
935 #else
936 if (rc == LDAP_NO_SUCH_OBJECT)
937 #endif
938
939 {
940 DEBUG(D_lookup) debug_printf("lookup failure forced\n");
941 error_yield = FAIL;
942 }
943 goto RETURN_ERROR;
944 }
945
946/* The search succeeded. Check if we have too many results */
947
948if (search_type != SEARCH_LDAP_MULTIPLE && rescount > 1)
949 {
950 *errmsg = string_sprintf("LDAP search: more than one entry (%d) was returned "
951 "(filter not specific enough?)", rescount);
952 goto RETURN_ERROR_BREAK;
953 }
954
955/* Check if we have too few (zero) entries */
956
957if (rescount < 1)
958 {
959 *errmsg = string_sprintf("LDAP search: no results");
960 error_yield = FAIL;
961 goto RETURN_ERROR_BREAK;
962 }
963
964/* If an entry was found, but it had no attributes, we behave as if no entries
965were found, that is, the lookup failed. */
966
967if (!attribute_found)
968 {
969 *errmsg = US"LDAP search: found no attributes";
970 error_yield = FAIL;
971 goto RETURN_ERROR;
972 }
973
974/* Otherwise, it's all worked */
975
976DEBUG(D_lookup) debug_printf("LDAP search: returning: %s\n", data);
977*res = data;
978
979RETURN_OK:
980if (result != NULL) ldap_msgfree(result);
981ldap_free_urldesc(ludp);
982return OK;
983
984/* Error returns */
985
986RETURN_ERROR_BREAK:
987*defer_break = TRUE;
988
989RETURN_ERROR:
990DEBUG(D_lookup) debug_printf("%s\n", *errmsg);
991
992RETURN_ERROR_NOMSG:
993if (result != NULL) ldap_msgfree(result);
994if (ludp != NULL) ldap_free_urldesc(ludp);
995
996#if defined LDAP_LIB_OPENLDAP2
997 if (error2 != NULL) ldap_memfree(error2);
998 if (matched != NULL) ldap_memfree(matched);
999#endif
1000
1001return error_yield;
1002}
1003
1004
1005
1006/*************************************************
1007* Internal search control function *
1008*************************************************/
1009
1010/* This function is called from eldap_find(), eldapauth_find(), eldapdn_find(),
1011and eldapm_find() with a difference in the "search_type" argument. It controls
1012calls to perform_ldap_search() which actually does the work. We call that
1013repeatedly for certain types of defer in the case when the URL contains no host
1014name and eldap_default_servers is set to a list of servers to try. This gives
1015more control than just passing over a list of hosts to ldap_open() because it
1016handles other kinds of defer as well as just a failure to open. Note that the
1017URL is defined to contain either zero or one "hostport" only.
1018
1019Parameter data in addition to the URL can be passed as preceding text in the
1020string, as items of the form XXX=yyy. The URL itself can be detected because it
1021must begin "ldapx://", where x is empty, s, or i.
1022
1023Arguments:
1024 ldap_url the URL to be looked up, optionally preceded by other parameter
1025 settings
1026 search_type SEARCH_LDAP_MULTIPLE allows values from multiple entries
1027 SEARCH_LDAP_SINGLE allows values from one entry only
1028 SEARCH_LDAP_DN gets the DN from one entry
1029 res set to point at the result
1030 errmsg set to point a message if result is not OK
1031
1032Returns: OK or FAIL or DEFER
1033*/
1034
1035static int
1036control_ldap_search(uschar *ldap_url, int search_type, uschar **res,
1037 uschar **errmsg)
1038{
1039BOOL defer_break = FALSE;
1040int timelimit = LDAP_NO_LIMIT;
1041int sizelimit = LDAP_NO_LIMIT;
7c7ad977 1042int tcplimit = 0;
0756eb3c 1043int sep = 0;
6ec97b1b
PH
1044int dereference = LDAP_DEREF_NEVER;
1045void* referrals = LDAP_OPT_ON;
0756eb3c
PH
1046uschar *url = ldap_url;
1047uschar *p;
1048uschar *user = NULL;
1049uschar *password = NULL;
1050uschar *server, *list;
1051uschar buffer[512];
1052
1053while (isspace(*url)) url++;
1054
1055/* Until the string begins "ldap", search for the other parameter settings that
1056are recognized. They are of the form NAME=VALUE, with the value being
1057optionally double-quoted. There must still be a space after it, however. No
1058NAME has the value "ldap". */
1059
1060while (strncmpic(url, US"ldap", 4) != 0)
1061 {
1062 uschar *name = url;
1063 while (*url != 0 && *url != '=') url++;
1064 if (*url == '=')
1065 {
1066 int namelen;
1067 uschar *value;
1068 namelen = ++url - name;
1069 value = string_dequote(&url);
1070 if (isspace(*url))
1071 {
1072 if (strncmpic(name, US"USER=", namelen) == 0) user = value;
1073 else if (strncmpic(name, US"PASS=", namelen) == 0) password = value;
1074 else if (strncmpic(name, US"SIZE=", namelen) == 0) sizelimit = Uatoi(value);
1075 else if (strncmpic(name, US"TIME=", namelen) == 0) timelimit = Uatoi(value);
7c7ad977
PH
1076 else if (strncmpic(name, US"CONNECT=", namelen) == 0) tcplimit = Uatoi(value);
1077 else if (strncmpic(name, US"NETTIME=", namelen) == 0) tcplimit = Uatoi(value);
0756eb3c
PH
1078
1079 /* Don't know if all LDAP libraries have LDAP_OPT_DEREF */
1080
1081 #ifdef LDAP_OPT_DEREF
1082 else if (strncmpic(name, US"DEREFERENCE=", namelen) == 0)
1083 {
1084 if (strcmpic(value, US"never") == 0) dereference = LDAP_DEREF_NEVER;
1085 else if (strcmpic(value, US"searching") == 0)
1086 dereference = LDAP_DEREF_SEARCHING;
1087 else if (strcmpic(value, US"finding") == 0)
1088 dereference = LDAP_DEREF_FINDING;
1089 if (strcmpic(value, US"always") == 0) dereference = LDAP_DEREF_ALWAYS;
1090 }
1091 #else
1092 else if (strncmpic(name, US"DEREFERENCE=", namelen) == 0)
1093 {
1094 *errmsg = string_sprintf("LDAP_OP_DEREF not defined in this LDAP "
1095 "library - cannot use \"dereference\"");
1096 DEBUG(D_lookup) debug_printf("%s\n", *errmsg);
1097 return DEFER;
1098 }
6ec97b1b 1099 #endif
0756eb3c 1100
6ec97b1b
PH
1101 #ifdef LDAP_OPT_REFERRALS
1102 else if (strncmpic(name, US"REFERRALS=", namelen) == 0)
1103 {
1104 if (strcmpic(value, US"follow") == 0) referrals = LDAP_OPT_ON;
1105 else if (strcmpic(value, US"nofollow") == 0) referrals = LDAP_OPT_OFF;
1106 else
1107 {
1108 *errmsg = string_sprintf("LDAP option REFERRALS is not \"follow\" "
1109 "or \"nofollow\"");
1110 DEBUG(D_lookup) debug_printf("%s\n", *errmsg);
1111 return DEFER;
1112 }
1113 }
1114 #else
1115 else if (strncmpic(name, US"REFERRALS=", namelen) == 0)
1116 {
1117 *errmsg = string_sprintf("LDAP_OP_REFERRALS not defined in this LDAP "
1118 "library - cannot use \"referrals\"");
1119 DEBUG(D_lookup) debug_printf("%s\n", *errmsg);
1120 return DEFER;
1121 }
0756eb3c
PH
1122 #endif
1123
1124 else
1125 {
1126 *errmsg =
1127 string_sprintf("unknown parameter \"%.*s\" precedes LDAP URL",
1128 namelen, name);
1129 DEBUG(D_lookup) debug_printf("LDAP query error: %s\n", *errmsg);
1130 return DEFER;
1131 }
1132 while (isspace(*url)) url++;
1133 continue;
1134 }
1135 }
1136 *errmsg = US"malformed parameter setting precedes LDAP URL";
1137 DEBUG(D_lookup) debug_printf("LDAP query error: %s\n", *errmsg);
1138 return DEFER;
1139 }
1140
1141/* If user is set, de-URL-quote it. Some LDAP libraries do this for themselves,
1142but it seems that not all behave like this. The DN for the user is often the
1143result of ${quote_ldap_dn:...} quoting, which does apply URL quoting, because
1144that is needed when the DN is used as a base DN in a query. Sigh. This is all
1145far too complicated. */
1146
1147if (user != NULL)
1148 {
1149 uschar *s;
1150 uschar *t = user;
1151 for (s = user; *s != 0; s++)
1152 {
1153 int c, d;
1154 if (*s == '%' && isxdigit(c=s[1]) && isxdigit(d=s[2]))
1155 {
1156 c = tolower(c);
1157 d = tolower(d);
1158 *t++ =
1159 (((c >= 'a')? (10 + c - 'a') : c - '0') << 4) |
1160 ((d >= 'a')? (10 + d - 'a') : d - '0');
1161 s += 2;
1162 }
1163 else *t++ = *s;
1164 }
1165 *t = 0;
1166 }
1167
1168DEBUG(D_lookup)
1169 debug_printf("LDAP parameters: user=%s pass=%s size=%d time=%d connect=%d "
6ec97b1b
PH
1170 "dereference=%d referrals=%s\n", user, password, sizelimit, timelimit,
1171 tcplimit, dereference, (referrals == LDAP_OPT_ON)? "on" : "off");
0756eb3c
PH
1172
1173/* If the request is just to check authentication, some credentials must
1174be given. The password must not be empty because LDAP binds with an empty
1175password are considered anonymous, and will succeed on most installations. */
1176
1177if (search_type == SEARCH_LDAP_AUTH)
1178 {
1179 if (user == NULL || password == NULL)
1180 {
1181 *errmsg = US"ldapauth lookups must specify the username and password";
1182 return DEFER;
1183 }
1184 if (password[0] == 0)
1185 {
1186 DEBUG(D_lookup) debug_printf("Empty password: ldapauth returns FAIL\n");
1187 return FAIL;
1188 }
1189 }
1190
1191/* Check for valid ldap url starters */
1192
1193p = url + 4;
1194if (tolower(*p) == 's' || tolower(*p) == 'i') p++;
1195if (Ustrncmp(p, "://", 3) != 0)
1196 {
1197 *errmsg = string_sprintf("LDAP URL does not start with \"ldap://\", "
1198 "\"ldaps://\", or \"ldapi://\" (it starts with \"%.16s...\")", url);
1199 DEBUG(D_lookup) debug_printf("LDAP query error: %s\n", *errmsg);
1200 return DEFER;
1201 }
1202
1203/* No default servers, or URL contains a server name: just one attempt */
1204
1205if (eldap_default_servers == NULL || p[3] != '/')
1206 {
1207 return perform_ldap_search(url, NULL, 0, search_type, res, errmsg,
6ec97b1b
PH
1208 &defer_break, user, password, sizelimit, timelimit, tcplimit, dereference,
1209 referrals);
0756eb3c
PH
1210 }
1211
1212/* Loop through the default servers until OK or FAIL */
1213
1214list = eldap_default_servers;
1215while ((server = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) != NULL)
1216 {
1217 int rc;
1218 int port = 0;
1219 uschar *colon = Ustrchr(server, ':');
1220 if (colon != NULL)
1221 {
1222 *colon = 0;
1223 port = Uatoi(colon+1);
1224 }
1225 rc = perform_ldap_search(url, server, port, search_type, res, errmsg,
6ec97b1b
PH
1226 &defer_break, user, password, sizelimit, timelimit, tcplimit, dereference,
1227 referrals);
0756eb3c
PH
1228 if (rc != DEFER || defer_break) return rc;
1229 }
1230
1231return DEFER;
1232}
1233
1234
1235
1236/*************************************************
1237* Find entry point *
1238*************************************************/
1239
1240/* See local README for interface description. The different kinds of search
1241are handled by a common function, with a flag to differentiate between them.
1242The handle and filename arguments are not used. */
1243
e6d225ae 1244static int
0756eb3c
PH
1245eldap_find(void *handle, uschar *filename, uschar *ldap_url, int length,
1246 uschar **result, uschar **errmsg, BOOL *do_cache)
1247{
1248/* Keep picky compilers happy */
1249do_cache = do_cache;
1250return(control_ldap_search(ldap_url, SEARCH_LDAP_SINGLE, result, errmsg));
1251}
1252
e6d225ae 1253static int
0756eb3c
PH
1254eldapm_find(void *handle, uschar *filename, uschar *ldap_url, int length,
1255 uschar **result, uschar **errmsg, BOOL *do_cache)
1256{
1257/* Keep picky compilers happy */
1258do_cache = do_cache;
1259return(control_ldap_search(ldap_url, SEARCH_LDAP_MULTIPLE, result, errmsg));
1260}
1261
e6d225ae 1262static int
0756eb3c
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1263eldapdn_find(void *handle, uschar *filename, uschar *ldap_url, int length,
1264 uschar **result, uschar **errmsg, BOOL *do_cache)
1265{
1266/* Keep picky compilers happy */
1267do_cache = do_cache;
1268return(control_ldap_search(ldap_url, SEARCH_LDAP_DN, result, errmsg));
1269}
1270
1271int
1272eldapauth_find(void *handle, uschar *filename, uschar *ldap_url, int length,
1273 uschar **result, uschar **errmsg, BOOL *do_cache)
1274{
1275/* Keep picky compilers happy */
1276do_cache = do_cache;
1277return(control_ldap_search(ldap_url, SEARCH_LDAP_AUTH, result, errmsg));
1278}
1279
1280
1281
1282/*************************************************
1283* Open entry point *
1284*************************************************/
1285
1286/* See local README for interface description. */
1287
e6d225ae 1288static void *
0756eb3c
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1289eldap_open(uschar *filename, uschar **errmsg)
1290{
1291return (void *)(1); /* Just return something non-null */
1292}
1293
1294
1295
1296/*************************************************
1297* Tidy entry point *
1298*************************************************/
1299
1300/* See local README for interface description.
1301Make sure that eldap_dn does not refer to reclaimed or worse, freed store */
1302
e6d225ae 1303static void
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1304eldap_tidy(void)
1305{
1306LDAP_CONNECTION *lcp = NULL;
1307eldap_dn = NULL;
1308
1309while ((lcp = ldap_connections) != NULL)
1310 {
1311 DEBUG(D_lookup) debug_printf("unbind LDAP connection to %s:%d\n", lcp->host,
1312 lcp->port);
1313 ldap_unbind(lcp->ld);
1314 ldap_connections = lcp->next;
1315 }
1316}
1317
1318
1319
1320/*************************************************
1321* Quote entry point *
1322*************************************************/
1323
1324/* LDAP quoting is unbelievably messy. For a start, two different levels of
1325quoting have to be done: LDAP quoting, and URL quoting. The current
1326specification is the result of a suggestion by Brian Candler. It recognizes
1327two separate cases:
1328
1329(1) For text that appears in a search filter, the following escapes are
1330 required (see RFC 2254):
1331
1332 * -> \2A
1333 ( -> \28
1334 ) -> \29
1335 \ -> \5C
1336 NULL -> \00
1337
1338 Then the entire filter text must be URL-escaped. This kind of quoting is
1339 implemented by ${quote_ldap:....}. Note that we can never have a NULL
1340 in the input string, because that's a terminator.
1341
1342(2) For a DN that is part of a URL (i.e. the base DN), the characters
1343
1344 , + " \ < > ;
1345
1346 must be quoted by backslashing. See RFC 2253. Leading and trailing spaces
1347 must be escaped, as must a leading #. Then the string must be URL-quoted.
1348 This type of quoting is implemented by ${quote_ldap_dn:....}.
1349
1350For URL quoting, the only characters that need not be quoted are the
1351alphamerics and
1352
1353 ! $ ' ( ) * + - . _
1354
1355All the others must be hexified and preceded by %. This includes the
1356backslashes used for LDAP quoting.
1357
1358For a DN that is given in the USER parameter for authentication, we need the
1359same initial quoting as (2) but in this case, the result must NOT be
1360URL-escaped, because it isn't a URL. The way this is handled is by
1361de-URL-quoting the text when processing the USER parameter in
1362control_ldap_search() above. That means that the same quote operator can be
1363used. This has the additional advantage that spaces in the DN won't cause
1364parsing problems. For example:
1365
1366 USER=cn=${quote_ldap_dn:$1},%20dc=example,%20dc=com
1367
1368should be safe if there are spaces in $1.
1369
1370
1371Arguments:
1372 s the string to be quoted
1373 opt additional option text or NULL if none
1374 only "dn" is recognized
1375
1376Returns: the processed string or NULL for a bad option
1377*/
1378
1379
1380
1381/* The characters in this string, together with alphanumerics, never need
1382quoting in any way. */
1383
1384#define ALWAYS_LITERAL "!$'-._"
1385
1386/* The special characters in this string do not need to be URL-quoted. The set
1387is a bit larger than the general literals. */
1388
1389#define URL_NONQUOTE ALWAYS_LITERAL "()*+"
1390
1391/* The following macros define the characters that are quoted by quote_ldap and
1392quote_ldap_dn, respectively. */
1393
1394#define LDAP_QUOTE "*()\\"
1395#define LDAP_DN_QUOTE ",+\"\\<>;"
1396
1397
1398
e6d225ae 1399static uschar *
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1400eldap_quote(uschar *s, uschar *opt)
1401{
1402register int c;
1403int count = 0;
1404int len = 0;
1405BOOL dn = FALSE;
1406uschar *t = s;
1407uschar *quoted;
1408
1409/* Test for a DN quotation. */
1410
1411if (opt != NULL)
1412 {
1413 if (Ustrcmp(opt, "dn") != 0) return NULL; /* No others recognized */
1414 dn = TRUE;
1415 }
1416
1417/* Compute how much extra store we need for the string. This doesn't have to be
1418exact as long as it isn't an underestimate. The worst case is the addition of 5
1419extra bytes for a single character. This occurs for certain characters in DNs,
1420where, for example, < turns into %5C%3C. For simplicity, we just add 5 for each
1421possibly escaped character. The really fast way would be just to test for
1422non-alphanumerics, but it is probably better to spot a few others that are
1423never escaped, because if there are no specials at all, we can avoid copying
1424the string. */
1425
1426while ((c = *t++) != 0)
1427 {
1428 len++;
1429 if (!isalnum(c) && Ustrchr(ALWAYS_LITERAL, c) == NULL) count += 5;
1430 }
1431if (count == 0) return s;
1432
1433/* Get sufficient store to hold the quoted string */
1434
1435t = quoted = store_get(len + count + 1);
1436
1437/* Handle plain quote_ldap */
1438
1439if (!dn)
1440 {
1441 while ((c = *s++) != 0)
1442 {
1443 if (!isalnum(c))
1444 {
1445 if (Ustrchr(LDAP_QUOTE, c) != NULL)
1446 {
1447 sprintf(CS t, "%%5C%02X", c); /* e.g. * => %5C2A */
1448 t += 5;
1449 continue;
1450 }
1451 if (Ustrchr(URL_NONQUOTE, c) == NULL) /* e.g. ] => %5D */
1452 {
1453 sprintf(CS t, "%%%02X", c);
1454 t += 3;
1455 continue;
1456 }
1457 }
1458 *t++ = c; /* unquoted character */
1459 }
1460 }
1461
1462/* Handle quote_ldap_dn */
1463
1464else
1465 {
1466 uschar *ss = s + len;
1467
1468 /* Find the last char before any trailing spaces */
1469
1470 while (ss > s && ss[-1] == ' ') ss--;
1471
1472 /* Quote leading spaces and sharps */
1473
1474 for (; s < ss; s++)
1475 {
1476 if (*s != ' ' && *s != '#') break;
1477 sprintf(CS t, "%%5C%%%02X", *s);
1478 t += 6;
1479 }
1480
1481 /* Handle the rest of the string, up to the trailing spaces */
1482
1483 while (s < ss)
1484 {
1485 c = *s++;
1486 if (!isalnum(c))
1487 {
1488 if (Ustrchr(LDAP_DN_QUOTE, c) != NULL)
1489 {
1490 Ustrncpy(t, "%5C", 3); /* insert \ where needed */
1491 t += 3; /* fall through to check URL */
1492 }
1493 if (Ustrchr(URL_NONQUOTE, c) == NULL) /* e.g. ] => %5D */
1494 {
1495 sprintf(CS t, "%%%02X", c);
1496 t += 3;
1497 continue;
1498 }
1499 }
1500 *t++ = c; /* unquoted character, or non-URL quoted after %5C */
1501 }
1502
1503 /* Handle the trailing spaces */
1504
1505 while (*ss++ != 0)
1506 {
1507 Ustrncpy(t, "%5C%20", 6);
1508 t += 6;
1509 }
1510 }
1511
1512/* Terminate the new string and return */
1513
1514*t = 0;
1515return quoted;
1516}
1517
6545de78
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1518
1519
1520/*************************************************
1521* Version reporting entry point *
1522*************************************************/
1523
1524/* See local README for interface description. */
1525
1526#include "../version.h"
1527
1528void
1529ldap_version_report(FILE *f)
1530{
1531#ifdef DYNLOOKUP
1532fprintf(f, "Library version: LDAP: Exim version %s\n", EXIM_VERSION_STR);
1533#endif
1534}
1535
1536
e6d225ae
DW
1537static lookup_info ldap_lookup_info = {
1538 US"ldap", /* lookup name */
1539 lookup_querystyle, /* query-style lookup */
1540 eldap_open, /* open function */
1541 NULL, /* check function */
1542 eldap_find, /* find function */
1543 NULL, /* no close function */
1544 eldap_tidy, /* tidy function */
6545de78
PP
1545 eldap_quote, /* quoting function */
1546 ldap_version_report /* version reporting */
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DW
1547};
1548
1549static lookup_info ldapdn_lookup_info = {
1550 US"ldapdn", /* lookup name */
1551 lookup_querystyle, /* query-style lookup */
1552 eldap_open, /* sic */ /* open function */
1553 NULL, /* check function */
1554 eldapdn_find, /* find function */
1555 NULL, /* no close function */
1556 eldap_tidy, /* sic */ /* tidy function */
6545de78
PP
1557 eldap_quote, /* sic */ /* quoting function */
1558 NULL /* no version reporting (redundant) */
e6d225ae
DW
1559};
1560
1561static lookup_info ldapm_lookup_info = {
1562 US"ldapm", /* lookup name */
1563 lookup_querystyle, /* query-style lookup */
1564 eldap_open, /* sic */ /* open function */
1565 NULL, /* check function */
1566 eldapm_find, /* find function */
1567 NULL, /* no close function */
1568 eldap_tidy, /* sic */ /* tidy function */
6545de78
PP
1569 eldap_quote, /* sic */ /* quoting function */
1570 NULL /* no version reporting (redundant) */
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DW
1571};
1572
1573#ifdef DYNLOOKUP
1574#define ldap_lookup_module_info _lookup_module_info
1575#endif
1576
1577static lookup_info *_lookup_list[] = { &ldap_lookup_info, &ldapdn_lookup_info, &ldapm_lookup_info };
1578lookup_module_info ldap_lookup_module_info = { LOOKUP_MODULE_INFO_MAGIC, _lookup_list, 3 };
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1579
1580/* End of lookups/ldap.c */