1 /* dirmngr-ldap.c  -  The LDAP helper for dirmngr.
2  * Copyright (C) 2004, 2021 g10 Code GmbH
3  * Copyright (C) 2010 Free Software Foundation, Inc.
4  *
5  * This file is part of GnuPG.
6  *
7  * GnuPG is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 3 of the License, or
10  * (at your option) any later version.
11  *
12  * GnuPG is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, see <https://www.gnu.org/licenses/>.
19  * SPDX-License-Identifier: GPL-3.0-or-later
20  */
21 
22 #include <config.h>
23 
24 
25 #include <stdio.h>
26 #include <stdlib.h>
27 #include <stddef.h>
28 #include <stdarg.h>
29 #include <string.h>
30 #ifdef HAVE_SIGNAL_H
31 # include <signal.h>
32 #endif
33 #include <errno.h>
34 #include <sys/time.h>
35 #include <unistd.h>
36 
37 #ifdef HAVE_W32_SYSTEM
38 # include <winsock2.h>
39 # include <winldap.h>
40 # include <winber.h>
41 # include <fcntl.h>
42 # include "ldap-url.h"
43 #else
44   /* For OpenLDAP, to enable the API that we're using. */
45 # define LDAP_DEPRECATED 1
46 # include <ldap.h>
47 #endif
48 
49 
50 #include <gpg-error.h>
51 #include "../common/logging.h"
52 #include "../common/stringhelp.h"
53 #include "../common/mischelp.h"
54 #include "../common/strlist.h"
55 #include "../common/util.h"
56 #include "../common/init.h"
57 #include "ldap-misc.h"
58 
59 
60 /* There is no need for the npth_unprotect and leave functions here;
61  * thus we redefine them to nops.  We keep them in the code just for
62  * the case we ever want to reuse parts of the code in npth programs. */
npth_unprotect(void)63 static void npth_unprotect (void) { }
npth_protect(void)64 static void npth_protect (void) { }
65 
66 
67 #ifdef HAVE_W32_SYSTEM
68  typedef LDAP_TIMEVAL  my_ldap_timeval_t;
69 #else
70  typedef struct timeval my_ldap_timeval_t;
71 #endif
72 
73 #define DEFAULT_LDAP_TIMEOUT 15 /* Arbitrary long timeout. */
74 
75 
76 /* Constants for the options.  */
77 enum
78   {
79     oQuiet	  = 'q',
80     oVerbose	  = 'v',
81 
82     oTimeout      = 500,
83     oMulti,
84     oProxy,
85     oHost,
86     oPort,
87     oUser,
88     oPass,
89     oEnvPass,
90     oBase,
91     oAttr,
92     oStartTLS,
93     oLdapTLS,
94     oNtds,
95     oOnlySearchTimeout,
96     oLogWithPID
97   };
98 
99 
100 /* The list of options as used by the argparse.c code.  */
101 static gpgrt_opt_t opts[] = {
102   { oVerbose,  "verbose",   0, "verbose" },
103   { oQuiet,    "quiet",     0, "be somewhat more quiet" },
104   { oTimeout,  "timeout",   1, "|N|set LDAP timeout to N seconds"},
105   { oMulti,    "multi",     0, "return all values in"
106                                " a record oriented format"},
107   { oProxy,    "proxy",     2,
108                 "|NAME|ignore host part and connect through NAME"},
109   { oStartTLS, "starttls",  0, "use STARTLS for the conenction"},
110   { oLdapTLS,  "ldaptls",   0, "use a TLS for the connection"},
111   { oNtds,     "ntds",      0, "authenticate using AD"},
112   { oHost,     "host",      2, "|NAME|connect to host NAME"},
113   { oPort,     "port",      1, "|N|connect to port N"},
114   { oUser,     "user",      2, "|NAME|use NAME for authentication"},
115   { oPass,     "pass",      2, "|PASS|use password PASS"
116                                " for authentication"},
117   { oEnvPass,  "env-pass",  0, "take password from $DIRMNGR_LDAP_PASS"},
118   { oBase,     "base",      2, "|DN|Start query at DN"},
119   { oAttr,     "attr",      2, "|STRING|return the attribute STRING"},
120   { oOnlySearchTimeout, "only-search-timeout", 0, "@"},
121   { oLogWithPID,"log-with-pid", 0, "@"},
122   ARGPARSE_end ()
123 };
124 
125 
126 /* A structure with module options.  */
127 static struct
128 {
129   int quiet;
130   int verbose;
131   my_ldap_timeval_t timeout;/* Timeout for the LDAP search functions.  */
132   unsigned int alarm_timeout; /* And for the alarm based timeout.  */
133   int multi;
134   int starttls;
135   int ldaptls;
136   int ntds;
137 
138   estream_t outstream;    /* Send output to this stream.  */
139 
140   /* Note that we can't use const for the strings because ldap_* are
141      not defined that way.  */
142   char *proxy; /* Host and Port override.  */
143   char *user;  /* Authentication user.  */
144   char *pass;  /* Authentication password.  */
145   char *host;  /* Override host.  */
146   int  port;   /* Override port.  */
147   char *base;  /* Override DN.  */
148   char *attr;  /* Override attribute.  */
149 } opt;
150 
151 
152 /* Prototypes.  */
153 #ifndef HAVE_W32_SYSTEM
154 static void catch_alarm (int dummy);
155 #endif
156 static gpg_error_t connect_ldap (LDAP **r_ld);
157 static gpg_error_t process_filter (LDAP *ld, const char *string);
158 
159 
160 
161 /* Function called by argparse.c to display information.  */
162 static const char *
my_strusage(int level)163 my_strusage (int level)
164 {
165   const char *p;
166 
167   switch (level)
168     {
169     case  9: p = "GPL-3.0-or-later"; break;
170     case 11: p = "dirmngr_ldap (@GNUPG@)";
171       break;
172     case 13: p = VERSION; break;
173     case 14: p = GNUPG_DEF_COPYRIGHT_LINE; break;
174     case 17: p = PRINTABLE_OS_NAME; break;
175     case 19: p = "Please report bugs to <@EMAIL@>.\n"; break;
176     case 49: p = PACKAGE_BUGREPORT; break;
177     case 1:
178     case 40: p =
179                "Usage: dirmngr_ldap [options] filters (-h for help)\n";
180       break;
181     case 41: p =
182            ("Syntax: dirmngr_ldap [options] filters\n"
183             "Internal LDAP helper for Dirmngr\n"
184             "Interface and options may change without notice\n");
185       break;
186 
187     default: p = NULL;
188     }
189   return p;
190 }
191 
192 
193 int
main(int argc,char ** argv)194 main (int argc, char **argv)
195 {
196   gpgrt_argparse_t pargs;
197   int any_err = 0;
198   char *p;
199   int only_search_timeout = 0;
200   char *malloced_buffer1 = NULL;
201   LDAP *ld;
202 
203   early_system_init ();
204 
205   gpgrt_set_strusage (my_strusage);
206   log_set_prefix ("dirmngr_ldap", GPGRT_LOG_WITH_PREFIX);
207 
208   init_common_subsystems (&argc, &argv);
209 
210   es_set_binary (es_stdout);
211   opt.outstream = es_stdout;
212 
213   /* LDAP defaults */
214   opt.timeout.tv_sec = DEFAULT_LDAP_TIMEOUT;
215   opt.timeout.tv_usec = 0;
216   opt.alarm_timeout = 0;
217 
218   /* Parse the command line.  */
219   pargs.argc = &argc;
220   pargs.argv = &argv;
221   pargs.flags= ARGPARSE_FLAG_KEEP;
222   while (gpgrt_argparse (NULL, &pargs, opts))
223     {
224       switch (pargs.r_opt)
225         {
226         case oVerbose: opt.verbose++; break;
227         case oQuiet: opt.quiet++; break;
228 	case oTimeout:
229 	  opt.timeout.tv_sec = pargs.r.ret_int;
230 	  opt.timeout.tv_usec = 0;
231           opt.alarm_timeout = pargs.r.ret_int;
232 	  break;
233         case oOnlySearchTimeout: only_search_timeout = 1; break;
234         case oStartTLS: opt.starttls = 1; opt.ldaptls = 0; break;
235         case oLdapTLS:  opt.starttls = 0; opt.ldaptls = 1; break;
236         case oNtds:     opt.ntds = 1; break;
237         case oMulti: opt.multi = 1; break;
238         case oUser: opt.user = pargs.r.ret_str; break;
239         case oPass: opt.pass = pargs.r.ret_str; break;
240         case oEnvPass:
241           opt.pass = getenv ("DIRMNGR_LDAP_PASS");
242           break;
243         case oProxy: opt.proxy = pargs.r.ret_str; break;
244         case oHost: opt.host = pargs.r.ret_str; break;
245         case oPort: opt.port = pargs.r.ret_int; break;
246         case oBase: opt.base = pargs.r.ret_str; break;
247         case oAttr: opt.attr = pargs.r.ret_str; break;
248         case oLogWithPID:
249           {
250             unsigned int oldflags;
251             log_get_prefix (&oldflags);
252             log_set_prefix (NULL, oldflags | GPGRT_LOG_WITH_PID);
253           }
254           break;
255 
256         default :
257           pargs.err = ARGPARSE_PRINT_ERROR;
258           break;
259 	}
260     }
261   gpgrt_argparse (NULL, &pargs, NULL);
262 
263   if (only_search_timeout)
264     opt.alarm_timeout = 0;
265 
266   if (opt.proxy)
267     {
268       malloced_buffer1 = xtrystrdup (opt.proxy);
269       if (!malloced_buffer1)
270         {
271           log_error ("error copying string: %s\n", strerror (errno));
272           return 1;
273         }
274       opt.host = malloced_buffer1;
275       p = strchr (opt.host, ':');
276       if (p)
277         {
278           *p++ = 0;
279           opt.port = atoi (p);
280         }
281       if (!opt.port)
282         opt.port = 389;  /* make sure ports gets overridden.  */
283     }
284 
285   if (opt.port < 0 || opt.port > 65535)
286     log_error ("invalid port number %d\n", opt.port);
287 
288   if (!opt.port)
289     opt.port = opt.ldaptls? 636 : 389;
290 
291 #ifndef HAVE_W32_SYSTEM
292   if (!opt.host)
293     opt.host = "localhost";
294 #endif
295 
296 
297   if (log_get_errorcount (0))
298     exit (2);
299 
300   if (opt.alarm_timeout)
301     {
302 #ifndef HAVE_W32_SYSTEM
303 # if defined(HAVE_SIGACTION) && defined(HAVE_STRUCT_SIGACTION)
304       struct sigaction act;
305 
306       act.sa_handler = catch_alarm;
307       sigemptyset (&act.sa_mask);
308       act.sa_flags = 0;
309       if (sigaction (SIGALRM,&act,NULL))
310 # else
311       if (signal (SIGALRM, catch_alarm) == SIG_ERR)
312 # endif
313           log_fatal ("unable to register timeout handler\n");
314 #endif
315     }
316 
317   if (connect_ldap (&ld))
318     any_err = 1;
319   else
320     {
321       if (!argc)
322         {
323           if (process_filter (ld, "(objectClass=*)"))
324             any_err = 1;
325         }
326       else
327         {
328           for (; argc; argc--, argv++)
329             if (process_filter (ld, *argv))
330               any_err = 1;
331         }
332       ldap_unbind (ld);
333     }
334 
335   xfree (malloced_buffer1);
336   return any_err;
337 }
338 
339 #ifndef HAVE_W32_SYSTEM
340 static void
catch_alarm(int dummy)341 catch_alarm (int dummy)
342 {
343   (void)dummy;
344   _exit (10);
345 }
346 #endif
347 
348 
349 #ifdef HAVE_W32_SYSTEM
350 static DWORD CALLBACK
alarm_thread(void * arg)351 alarm_thread (void *arg)
352 {
353   HANDLE timer = arg;
354 
355   WaitForSingleObject (timer, INFINITE);
356   _exit (10);
357 
358   return 0;
359 }
360 #endif
361 
362 
363 static void
set_timeout(void)364 set_timeout (void)
365 {
366   if (opt.alarm_timeout)
367     {
368 #ifdef HAVE_W32_SYSTEM
369       static HANDLE timer;
370       LARGE_INTEGER due_time;
371 
372       /* A negative value is a relative time.  */
373       due_time.QuadPart = (unsigned long long)-10000000 * opt.alarm_timeout;
374 
375       if (!timer)
376         {
377           SECURITY_ATTRIBUTES sec_attr;
378           DWORD tid;
379 
380           memset (&sec_attr, 0, sizeof sec_attr);
381           sec_attr.nLength = sizeof sec_attr;
382           sec_attr.bInheritHandle = FALSE;
383 
384           /* Create a manual resettable timer.  */
385           timer = CreateWaitableTimer (NULL, TRUE, NULL);
386           /* Initially set the timer.  */
387           SetWaitableTimer (timer, &due_time, 0, NULL, NULL, 0);
388 
389           if (CreateThread (&sec_attr, 0, alarm_thread, timer, 0, &tid))
390             log_error ("failed to create alarm thread\n");
391         }
392       else /* Retrigger the timer.  */
393         SetWaitableTimer (timer, &due_time, 0, NULL, NULL, 0);
394 #else
395       alarm (opt.alarm_timeout);
396 #endif
397     }
398 }
399 
400 
401 
402 /* Connect to the ldap server.  On success the connection handle is
403  * stored at R_LD. */
404 static gpg_error_t
connect_ldap(LDAP ** r_ld)405 connect_ldap (LDAP **r_ld)
406 {
407   gpg_error_t err = 0;
408   int lerr;
409   LDAP *ld = NULL;
410 #ifndef HAVE_W32_SYSTEM
411   char *tmpstr;
412 #endif
413 
414   *r_ld = NULL;
415 
416   if (opt.starttls || opt.ldaptls)
417     {
418 #ifndef HAVE_LDAP_START_TLS_S
419       log_error ("ldap: can't connect to the server: no TLS support.");
420       err = GPG_ERR_LDAP_NOT_SUPPORTED;
421       goto leave;
422 #endif
423     }
424 
425 
426   set_timeout ();
427 #ifdef HAVE_W32_SYSTEM
428   npth_unprotect ();
429   ld = ldap_sslinit (opt.host, opt.port, opt.ldaptls);
430   npth_protect ();
431   if (!ld)
432     {
433       lerr = LdapGetLastError ();
434       err = ldap_err_to_gpg_err (lerr);
435       log_error ("error initializing LDAP '%s:%d': %s\n",
436                  opt.host, opt.port, ldap_err2string (lerr));
437       goto leave;
438     }
439 #else /* Unix */
440   tmpstr = xtryasprintf ("%s://%s:%d",
441                          opt.ldaptls? "ldaps" : "ldap",
442                          opt.host, opt.port);
443   if (!tmpstr)
444     {
445       err = gpg_error_from_syserror ();
446       goto leave;
447     }
448   npth_unprotect ();
449   lerr = ldap_initialize (&ld, tmpstr);
450   npth_protect ();
451   if (lerr || !ld)
452     {
453       err = ldap_err_to_gpg_err (lerr);
454       log_error ("error initializing LDAP '%s': %s\n",
455                  tmpstr, ldap_err2string (lerr));
456       xfree (tmpstr);
457       goto leave;
458     }
459   xfree (tmpstr);
460 #endif /* Unix */
461 
462   if (opt.verbose)
463     log_info ("LDAP connected to '%s:%d'%s\n",
464               opt.host, opt.port,
465               opt.starttls? " using STARTTLS" :
466               opt.ldaptls?  " using LDAP-over-TLS" : "");
467 
468 
469 #ifdef HAVE_LDAP_SET_OPTION
470   {
471     int ver = LDAP_VERSION3;
472 
473     lerr = ldap_set_option (ld, LDAP_OPT_PROTOCOL_VERSION, &ver);
474     if (lerr != LDAP_SUCCESS)
475       {
476 	log_error ("unable to go to LDAP 3: %s\n", ldap_err2string (lerr));
477 	err = ldap_err_to_gpg_err (lerr);
478 	goto leave;
479       }
480   }
481 #endif
482 
483 
484 #ifdef HAVE_LDAP_START_TLS_S
485   if (opt.starttls)
486     {
487 #ifndef HAVE_W32_SYSTEM
488       int check_cert = LDAP_OPT_X_TLS_HARD; /* LDAP_OPT_X_TLS_NEVER */
489 
490       lerr = ldap_set_option (ld, LDAP_OPT_X_TLS_REQUIRE_CERT, &check_cert);
491       if (lerr)
492 	{
493 	  log_error ("ldap: error setting an TLS option: %s\n",
494                      ldap_err2string (lerr));
495           err = ldap_err_to_gpg_err (lerr);
496 	  goto leave;
497 	}
498 #else
499       /* On Windows, the certificates are checked by default.  If the
500 	 option to disable checking mentioned above is ever
501 	 implemented, the way to do that on Windows is to install a
502 	 callback routine using ldap_set_option (..,
503 	 LDAP_OPT_SERVER_CERTIFICATE, ..); */
504 #endif
505 
506       npth_unprotect ();
507       lerr = ldap_start_tls_s (ld,
508 #ifdef HAVE_W32_SYSTEM
509 			      /* ServerReturnValue, result */
510 			      NULL, NULL,
511 #endif
512 			      /* ServerControls, ClientControls */
513 			      NULL, NULL);
514       npth_protect ();
515       if (lerr)
516 	{
517 	  log_error ("ldap: error switching to STARTTLS mode: %s\n",
518                      ldap_err2string (lerr));
519           err = ldap_err_to_gpg_err (lerr);
520 	  goto leave;
521 	}
522     }
523 #endif
524 
525   if (opt.ntds)
526     {
527       if (opt.verbose)
528         log_info ("binding to current user via AD\n");
529 #ifdef HAVE_W32_SYSTEM
530       npth_unprotect ();
531       lerr = ldap_bind_s (ld, NULL, NULL, LDAP_AUTH_NEGOTIATE);
532       npth_protect ();
533       if (lerr != LDAP_SUCCESS)
534 	{
535 	  log_error ("error binding to LDAP via AD: %s\n",
536                      ldap_err2string (lerr));
537           err = ldap_err_to_gpg_err (lerr);
538 	  goto leave;
539 	}
540 #else /* Unix */
541       err = gpg_error (GPG_ERR_NOT_SUPPORTED);
542       goto leave;
543 #endif /* Unix */
544     }
545   else if (opt.user)
546     {
547       if (opt.verbose)
548         log_info ("LDAP bind to '%s', password '%s'\n",
549                    opt.user, opt.pass ? ">not_shown<" : ">none<");
550 
551       npth_unprotect ();
552       lerr = ldap_simple_bind_s (ld, opt.user, opt.pass);
553       npth_protect ();
554       if (lerr != LDAP_SUCCESS)
555 	{
556 	  log_error ("error binding to LDAP: %s\n", ldap_err2string (lerr));
557           err = ldap_err_to_gpg_err (lerr);
558 	  goto leave;
559 	}
560     }
561   else
562     {
563       /* By default we don't bind as there is usually no need to.  */
564     }
565 
566  leave:
567   if (err)
568     {
569       if (ld)
570         ldap_unbind (ld);
571     }
572   else
573     *r_ld = ld;
574   return err;
575 }
576 
577 
578 /* Helper for fetch_ldap().  */
579 static int
print_ldap_entries(LDAP * ld,LDAPMessage * msg,char * want_attr)580 print_ldap_entries (LDAP *ld, LDAPMessage *msg, char *want_attr)
581 {
582   LDAPMessage *item;
583   int any = 0;
584 
585   for (npth_unprotect (), item = ldap_first_entry (ld, msg), npth_protect ();
586        item;
587        npth_unprotect (), item = ldap_next_entry (ld, item), npth_protect ())
588     {
589       BerElement *berctx;
590       char *attr;
591 
592       if (opt.verbose > 1)
593         log_info ("scanning result for attribute '%s'\n",
594                   want_attr? want_attr : "[all]");
595 
596       if (opt.multi)
597         { /*  Write item marker. */
598           if (es_fwrite ("I\0\0\0\0", 5, 1, opt.outstream) != 1)
599             {
600               log_error ("error writing to stdout: %s\n",
601                          strerror (errno));
602               return -1;
603             }
604         }
605 
606 
607       for (npth_unprotect (), attr = ldap_first_attribute (ld, item, &berctx),
608              npth_protect ();
609            attr;
610            npth_unprotect (), attr = ldap_next_attribute (ld, item, berctx),
611              npth_protect ())
612         {
613           struct berval **values;
614           int idx;
615 
616           if (opt.verbose > 1)
617             log_info ("          available attribute '%s'\n", attr);
618 
619           set_timeout ();
620 
621           /* I case we want only one attribute we do a case
622              insensitive compare without the optional extension
623              (i.e. ";binary").  Case insensitive is not really correct
624              but the best we can do.  */
625           if (want_attr)
626             {
627               char *cp1, *cp2;
628               int cmpres;
629 
630               cp1 = strchr (want_attr, ';');
631               if (cp1)
632                 *cp1 = 0;
633               cp2 = strchr (attr, ';');
634               if (cp2)
635                 *cp2 = 0;
636               cmpres = ascii_strcasecmp (want_attr, attr);
637               if (cp1)
638                 *cp1 = ';';
639               if (cp2)
640                 *cp2 = ';';
641               if (cmpres)
642                 {
643                   ldap_memfree (attr);
644                   continue; /* Not found:  Try next attribute.  */
645                 }
646             }
647 
648           npth_unprotect ();
649           values = ldap_get_values_len (ld, item, attr);
650           npth_protect ();
651 
652           if (!values)
653             {
654               if (opt.verbose)
655                 log_info ("attribute '%s' not found\n", attr);
656               ldap_memfree (attr);
657               continue;
658             }
659 
660           if (opt.verbose)
661             {
662               log_info ("found attribute '%s'\n", attr);
663               if (opt.verbose > 1)
664                 for (idx=0; values[idx]; idx++)
665                   log_info ("         length[%d]=%d\n",
666                             idx, (int)values[0]->bv_len);
667 
668             }
669 
670           if (opt.multi)
671             { /*  Write attribute marker. */
672               unsigned char tmp[5];
673               size_t n = strlen (attr);
674 
675               tmp[0] = 'A';
676               tmp[1] = (n >> 24);
677               tmp[2] = (n >> 16);
678               tmp[3] = (n >> 8);
679               tmp[4] = (n);
680               if (es_fwrite (tmp, 5, 1, opt.outstream) != 1
681                   || es_fwrite (attr, n, 1, opt.outstream) != 1)
682                 {
683                   log_error ("error writing to stdout: %s\n",
684                              strerror (errno));
685                   ldap_value_free_len (values);
686                   ldap_memfree (attr);
687                   ber_free (berctx, 0);
688                   return -1;
689                 }
690             }
691 
692           for (idx=0; values[idx]; idx++)
693             {
694               if (opt.multi)
695                 { /* Write value marker.  */
696                   unsigned char tmp[5];
697                   size_t n = values[0]->bv_len;
698 
699                   tmp[0] = 'V';
700                   tmp[1] = (n >> 24);
701                   tmp[2] = (n >> 16);
702                   tmp[3] = (n >> 8);
703                   tmp[4] = (n);
704 
705                   if (es_fwrite (tmp, 5, 1, opt.outstream) != 1)
706                     {
707                       log_error ("error writing to stdout: %s\n",
708                                  strerror (errno));
709                       ldap_value_free_len (values);
710                       ldap_memfree (attr);
711                       ber_free (berctx, 0);
712                       return -1;
713                     }
714                 }
715 
716 	      if (es_fwrite (values[0]->bv_val, values[0]->bv_len,
717                              1, opt.outstream) != 1)
718                 {
719                   log_error ("error writing to stdout: %s\n",
720                              strerror (errno));
721                   ldap_value_free_len (values);
722                   ldap_memfree (attr);
723                   ber_free (berctx, 0);
724                   return -1;
725                 }
726 
727               any = 1;
728               if (!opt.multi)
729                 break; /* Print only the first value.  */
730             }
731           ldap_value_free_len (values);
732           ldap_memfree (attr);
733           if (want_attr || !opt.multi)
734             break; /* We only want to return the first attribute.  */
735         }
736       ber_free (berctx, 0);
737     }
738 
739   if (opt.verbose > 1 && any)
740     log_info ("result has been printed\n");
741 
742   return any?0:-1;
743 }
744 
745 
746 
747 /* Fetch data from the server at LD using FILTER.  */
748 static int
fetch_ldap(LDAP * ld,const char * base,int scope,const char * filter)749 fetch_ldap (LDAP *ld, const char *base, int scope, const char *filter)
750 {
751   gpg_error_t err;
752   int lerr;
753   LDAPMessage *msg;
754   char *attrs[2];
755 
756   if (filter && !*filter)
757     filter = NULL;
758 
759   if (opt.verbose)
760     {
761       log_info ("fetching using");
762       if (base)
763         log_printf (" base '%s'", base);
764       if (filter)
765         log_printf (" filter '%s'", filter);
766       log_printf ("\n");
767     }
768 
769   attrs[0] = opt.attr;
770   attrs[1] = NULL;
771 
772   set_timeout ();
773   npth_unprotect ();
774   lerr = ldap_search_st (ld, base, scope, filter,
775                          attrs,
776                          0,
777                          &opt.timeout, &msg);
778   npth_protect ();
779   if (lerr == LDAP_SIZELIMIT_EXCEEDED && opt.multi)
780     {
781       if (es_fwrite ("E\0\0\0\x09truncated", 14, 1, opt.outstream) != 1)
782         {
783           log_error ("error writing to stdout: %s\n", strerror (errno));
784           return -1;
785         }
786     }
787   else if (lerr)
788     {
789       log_error ("searching '%s' failed: %s\n",
790                  filter, ldap_err2string (lerr));
791       if (lerr != LDAP_NO_SUCH_OBJECT)
792         {
793           /* FIXME: Need deinit (ld)?  */
794           /* Hmmm: Do we need to released MSG in case of an error? */
795           return -1;
796         }
797     }
798 
799   err = print_ldap_entries (ld, msg, opt.multi? NULL:opt.attr);
800 
801   ldap_msgfree (msg);
802   return err;
803 }
804 
805 
806 
807 
808 /* Main processing.  Take the filter and run the LDAP query. The
809  * result is printed to stdout, errors are logged to the log stream.
810  * To allow searching with a different base it is possible to extend
811  * the filer.  For example:
812  *
813  *   ^CN=foo, OU=My Users&(objectClasses=*)
814  *
815  * Uses "CN=foo, OU=My Users" as base DN and "(objectClasses=*)" as
816  * filter.  If the base prefix includes an ampersand, it needs to be
817  * doubled.  The usual escaping rules for DNs (for the base) and
818  * filters apply.  If no scope is given (see ldap_parse_extfilter for
819  * the syntax) subtree scope is used.
820  */
821 static gpg_error_t
process_filter(LDAP * ld,const char * string)822 process_filter (LDAP *ld, const char *string)
823 {
824   gpg_error_t err;
825   char *base, *filter;
826   int scope = -1;
827 
828   err = ldap_parse_extfilter (string, 0, &base, &scope, &filter);
829   if (!err)
830     err = fetch_ldap (ld,
831                       base? base : opt.base,
832                       scope == -1? LDAP_SCOPE_SUBTREE : scope,
833                       filter);
834 
835   xfree (base);
836   xfree (filter);
837   return err;
838 }
839