ldap/apr_ldap_url.c

   1 /* Copyright 2000-2005 The Apache Software Foundation or its licensors, as
   2  * applicable.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 /* Portions Copyright 1998-2002 The OpenLDAP Foundation
  18  * All rights reserved.
  19  *
  20  * Redistribution and use in source and binary forms, with or without
  21  * modification, are permitted only as authorized by the OpenLDAP
  22  * Public License.  A copy of this license is available at
  23  * http://www.OpenLDAP.org/license.html or in file LICENSE in the
  24  * top-level directory of the distribution.
  25  *
  26  * OpenLDAP is a registered trademark of the OpenLDAP Foundation.
  27  *
  28  * Individual files and/or contributed packages may be copyright by
  29  * other parties and subject to additional restrictions.
  30  *
  31  * This work is derived from the University of Michigan LDAP v3.3
  32  * distribution.  Information concerning this software is available
  33  * at: http://www.umich.edu/~dirsvcs/ldap/
  34  *
  35  * This work also contains materials derived from public sources.
  36  *
  37  * Additional information about OpenLDAP can be obtained at:
  38  *     http://www.openldap.org/
  39  */
  40
  41 /*
  42  * Portions Copyright (c) 1992-1996 Regents of the University of Michigan.
  43  * All rights reserved.
  44  *
  45  * Redistribution and use in source and binary forms are permitted
  46  * provided that this notice is preserved and that due credit is given
  47  * to the University of Michigan at Ann Arbor. The name of the University
  48  * may not be used to endorse or promote products derived from this
  49  * software without specific prior written permission. This software
  50  * is provided ``as is'' without express or implied warranty.
  51  */
  52
  53 /*  apr_ldap_url.c -- LDAP URL (RFC 2255) related routines
  54  *
  55  *  Win32 and perhaps other non-OpenLDAP based ldap libraries may be
  56  *  missing ldap_url_* APIs.  We focus here on the one significant
  57  *  aspect, which is parsing.  We have [for the time being] omitted
  58  *  the ldap_url_search APIs.
  59  *
  60  *  LDAP URLs look like this:
  61  *    ldap[is]://host:port[/[dn[?[attributes][?[scope][?[filter][?exts]]]]]]
  62  *
  63  *  where:
  64  *   attributes is a comma separated list
  65  *   scope is one of these three strings:  base one sub (default=base)
  66  *   filter is an string-represented filter as in RFC 2254
  67  *
  68  *  e.g.,  ldap://host:port/dc=com?o,cn?base?o=openldap?extension
  69  *
  70  *  Tolerates URLs that look like: <ldapurl> and <URL:ldapurl>
  71  */
  72
  73 #include "apu.h"
  74 #include "apr_pools.h"
  75 #include "apr_general.h"
  76 #include "apr_strings.h"
  77 #include "apr_ldap.h"
  78
  79 #if APR_HAS_LDAP
  80
  81 #if APR_HAVE_STDLIB_H
  82 #include <stdlib.h>
  83 #endif
  84
  85 #ifndef LDAPS_PORT
  86 #define LDAPS_PORT              636  /* ldaps:/// default LDAP over TLS port */
  87 #endif
  88
  89 #define APR_LDAP_URL_PREFIX         "ldap://"
  90 #define APR_LDAP_URL_PREFIX_LEN     (sizeof(APR_LDAP_URL_PREFIX)-1)
  91 #define APR_LDAPS_URL_PREFIX        "ldaps://"
  92 #define APR_LDAPS_URL_PREFIX_LEN    (sizeof(APR_LDAPS_URL_PREFIX)-1)
  93 #define APR_LDAPI_URL_PREFIX        "ldapi://"
  94 #define APR_LDAPI_URL_PREFIX_LEN    (sizeof(APR_LDAPI_URL_PREFIX)-1)
  95 #define APR_LDAP_URL_URLCOLON       "URL:"
  96 #define APR_LDAP_URL_URLCOLON_LEN   (sizeof(APR_LDAP_URL_URLCOLON)-1)
  97
  98
  99 /* local functions */
 100 static const char* skip_url_prefix(const char *url,
 101                                    int *enclosedp,
 102                                    const char **scheme);
 103
 104 static void apr_ldap_pvt_hex_unescape(char *s);
 105
 106 static int apr_ldap_pvt_unhex(int c);
 107
 108 static char **apr_ldap_str2charray(apr_pool_t *pool,
 109                                    const char *str,
 110                                    const char *brkstr);
 111
 112
 113 /**
 114  * Is this URL an ldap url?
 115  *
 116  */
 117 APU_DECLARE(int) apr_ldap_is_ldap_url(const char *url)
 118 {
 119     int enclosed;
 120     const char * scheme;
 121
 122     if( url == NULL ) {
 123         return 0;
 124     }
 125
 126     if( skip_url_prefix( url, &enclosed, &scheme ) == NULL ) {
 127         return 0;
 128     }
 129
 130     return 1;
 131 }
 132
 133 /**
 134  * Is this URL a secure ldap url?
 135  *
 136  */
 137 APU_DECLARE(int) apr_ldap_is_ldaps_url(const char *url)
 138 {
 139     int enclosed;
 140     const char * scheme;
 141
 142     if( url == NULL ) {
 143         return 0;
 144     }
 145
 146     if( skip_url_prefix( url, &enclosed, &scheme ) == NULL ) {
 147         return 0;
 148     }
 149
 150     return strcmp(scheme, "ldaps") == 0;
 151 }
 152
 153 /**
 154  * Is this URL an ldap socket url?
 155  *
 156  */
 157 APU_DECLARE(int) apr_ldap_is_ldapi_url(const char *url)
 158 {
 159     int enclosed;
 160     const char * scheme;
 161
 162     if( url == NULL ) {
 163         return 0;
 164     }
 165
 166     if( skip_url_prefix( url, &enclosed, &scheme ) == NULL ) {
 167         return 0;
 168     }
 169
 170     return strcmp(scheme, "ldapi") == 0;
 171 }
 172
 173
 174 static const char *skip_url_prefix(const char *url, int *enclosedp,
 175                                    const char **scheme)
 176 {
 177     /*
 178      * return non-zero if this looks like a LDAP URL; zero if not
 179      * if non-zero returned, *urlp will be moved past "ldap://" part of URL
 180      */
 181     const char *p;
 182
 183     if ( url == NULL ) {
 184         return( NULL );
 185     }
 186
 187     p = url;
 188
 189     /* skip leading '<' (if any) */
 190     if ( *p == '<' ) {
 191         *enclosedp = 1;
 192         ++p;
 193     } else {
 194         *enclosedp = 0;
 195     }
 196
 197     /* skip leading "URL:" (if any) */
 198     if ( strncasecmp( p, APR_LDAP_URL_URLCOLON, APR_LDAP_URL_URLCOLON_LEN ) == 0 ) {
 199         p += APR_LDAP_URL_URLCOLON_LEN;
 200     }
 201
 202     /* check for "ldap://" prefix */
 203     if ( strncasecmp( p, APR_LDAP_URL_PREFIX, APR_LDAP_URL_PREFIX_LEN ) == 0 ) {
 204         /* skip over "ldap://" prefix and return success */
 205         p += APR_LDAP_URL_PREFIX_LEN;
 206         *scheme = "ldap";
 207         return( p );
 208     }
 209
 210     /* check for "ldaps://" prefix */
 211     if ( strncasecmp( p, APR_LDAPS_URL_PREFIX, APR_LDAPS_URL_PREFIX_LEN ) == 0 ) {
 212         /* skip over "ldaps://" prefix and return success */
 213         p += APR_LDAPS_URL_PREFIX_LEN;
 214         *scheme = "ldaps";
 215         return( p );
 216     }
 217
 218     /* check for "ldapi://" prefix */
 219     if ( strncasecmp( p, APR_LDAPI_URL_PREFIX, APR_LDAPI_URL_PREFIX_LEN ) == 0 ) {
 220         /* skip over "ldapi://" prefix and return success */
 221         p += APR_LDAPI_URL_PREFIX_LEN;
 222         *scheme = "ldapi";
 223         return( p );
 224     }
 225
 226     return( NULL );
 227 }
 228
 229
 230 static int str2scope(const char *p)
 231 {
 232     if ( strcasecmp( p, "one" ) == 0 ) {
 233         return LDAP_SCOPE_ONELEVEL;
 234
 235     } else if ( strcasecmp( p, "onetree" ) == 0 ) {
 236         return LDAP_SCOPE_ONELEVEL;
 237
 238     } else if ( strcasecmp( p, "base" ) == 0 ) {
 239         return LDAP_SCOPE_BASE;
 240
 241     } else if ( strcasecmp( p, "sub" ) == 0 ) {
 242         return LDAP_SCOPE_SUBTREE;
 243
 244     } else if ( strcasecmp( p, "subtree" ) == 0 ) {
 245         return LDAP_SCOPE_SUBTREE;
 246     }
 247
 248     return( -1 );
 249 }
 250
 251
 252 /**
 253  * Parse the URL provided into an apr_ldap_url_desc_t object.
 254  *
 255  * APR_SUCCESS is returned on success, APR_EGENERAL on failure.
 256  * The LDAP result code and reason string is returned in the
 257  * apr_ldap_err_t structure.
 258  */
 259 APU_DECLARE(int) apr_ldap_url_parse_ext(apr_pool_t *pool,
 260                                         const char *url_in,
 261                                         apr_ldap_url_desc_t **ludpp,
 262                                         apr_ldap_err_t **result_err)
 263 {
 264     apr_ldap_url_desc_t *ludp;
 265     char        *p, *q, *r;
 266     int         i, enclosed;
 267     const char  *scheme = NULL;
 268     const char  *url_tmp;
 269     char        *url;
 270
 271     apr_ldap_err_t *result = (apr_ldap_err_t *)apr_pcalloc(pool, sizeof(apr_ldap_err_t));
 272     *result_err = result;
 273
 274     /* sanity check our parameters */
 275     if( url_in == NULL || ludpp == NULL ) {
 276         result->reason = "Either the LDAP URL, or the URL structure was NULL. Oops.";
 277         result->rc = APR_LDAP_URL_ERR_PARAM;
 278         return APR_EGENERAL;
 279     }
 280
 281     *ludpp = NULL;  /* pessimistic */
 282
 283     url_tmp = skip_url_prefix( url_in, &enclosed, &scheme );
 284     if ( url_tmp == NULL ) {
 285         result->reason = "The scheme was not recognised as a valid LDAP URL scheme.";
 286         result->rc = APR_LDAP_URL_ERR_BADSCHEME;
 287         return APR_EGENERAL;
 288     }
 289
 290     /* make working copy of the remainder of the URL */
 291     url = (char *)apr_pstrdup(pool, url_tmp);
 292     if ( url == NULL ) {
 293         result->reason = "Out of memory parsing LDAP URL.";
 294         result->rc = APR_LDAP_URL_ERR_MEM;
 295         return APR_EGENERAL;
 296     }
 297
 298     if ( enclosed ) {
 299         p = &url[strlen(url)-1];
 300
 301         if( *p != '>' ) {
 302             result->reason = "Bad enclosure error while parsing LDAP URL.";
 303             result->rc = APR_LDAP_URL_ERR_BADENCLOSURE;
 304             return APR_EGENERAL;
 305         }
 306
 307         *p = '\0';
 308     }
 309
 310     /* allocate return struct */
 311     ludp = (apr_ldap_url_desc_t *)apr_pcalloc(pool, sizeof(apr_ldap_url_desc_t));
 312     if ( ludp == NULL ) {
 313         result->reason = "Out of memory parsing LDAP URL.";
 314         result->rc = APR_LDAP_URL_ERR_MEM;
 315         return APR_EGENERAL;
 316     }
 317
 318     ludp->lud_next = NULL;
 319     ludp->lud_host = NULL;
 320     ludp->lud_port = LDAP_PORT;
 321     ludp->lud_dn = NULL;
 322     ludp->lud_attrs = NULL;
 323     ludp->lud_filter = NULL;
 324     ludp->lud_scope = -1;
 325     ludp->lud_filter = NULL;
 326     ludp->lud_exts = NULL;
 327
 328     ludp->lud_scheme = (char *)apr_pstrdup(pool, scheme);
 329     if ( ludp->lud_scheme == NULL ) {
 330         result->reason = "Out of memory parsing LDAP URL.";
 331         result->rc = APR_LDAP_URL_ERR_MEM;
 332         return APR_EGENERAL;
 333     }
 334
 335     if( strcasecmp( ludp->lud_scheme, "ldaps" ) == 0 ) {
 336         ludp->lud_port = LDAPS_PORT;
 337     }
 338
 339     /* scan forward for '/' that marks end of hostport and begin. of dn */
 340     p = strchr( url, '/' );
 341
 342     if( p != NULL ) {
 343         /* terminate hostport; point to start of dn */
 344         *p++ = '\0';
 345     }
 346
 347     /* IPv6 syntax with [ip address]:port */
 348     if ( *url == '[' ) {
 349         r = strchr( url, ']' );
 350         if ( r == NULL ) {
 351             result->reason = "Bad LDAP URL while parsing IPV6 syntax.";
 352             result->rc = APR_LDAP_URL_ERR_BADURL;
 353             return APR_EGENERAL;
 354         }
 355         *r++ = '\0';
 356         q = strrchr( r, ':' );
 357     } else {
 358         q = strrchr( url, ':' );
 359     }
 360
 361     if ( q != NULL ) {
 362         apr_ldap_pvt_hex_unescape( ++q );
 363
 364         if( *q == '\0' ) {
 365             result->reason = "Bad LDAP URL while parsing.";
 366             result->rc = APR_LDAP_URL_ERR_BADURL;
 367             return APR_EGENERAL;
 368         }
 369
 370         ludp->lud_port = atoi( q );
 371     }
 372
 373     apr_ldap_pvt_hex_unescape( url );
 374
 375     /* If [ip address]:port syntax, url is [ip and we skip the [ */
 376     ludp->lud_host = (char *)apr_pstrdup(pool, url + ( *url == '[' ));
 377     if( ludp->lud_host == NULL ) {
 378         result->reason = "Out of memory parsing LDAP URL.";
 379         result->rc = APR_LDAP_URL_ERR_MEM;
 380         return APR_EGENERAL;
 381     }
 382
 383     /*
 384      * Kludge.  ldap://111.222.333.444:389??cn=abc,o=company
 385      *
 386      * On early Novell releases, search references/referrals were returned
 387      * in this format, i.e., the dn was kind of in the scope position,
 388      * but the required slash is missing. The whole thing is illegal syntax,
 389      * but we need to account for it. Fortunately it can't be confused with
 390      * anything real.
 391      */
 392     if( (p == NULL) && (q != NULL) && ((q = strchr( q, '?')) != NULL)) {
 393         q++;
 394         /* ? immediately followed by question */
 395         if( *q == '?') {
 396             q++;
 397             if( *q != '\0' ) {
 398                 /* parse dn part */
 399                 apr_ldap_pvt_hex_unescape( q );
 400                 ludp->lud_dn = (char *)apr_pstrdup(pool, q);
 401             } else {
 402                 ludp->lud_dn = (char *)apr_pstrdup(pool, "");
 403             }
 404
 405             if( ludp->lud_dn == NULL ) {
 406                 result->reason = "Out of memory parsing LDAP URL.";
 407                 result->rc = APR_LDAP_URL_ERR_MEM;
 408                 return APR_EGENERAL;
 409             }
 410         }
 411     }
 412
 413     if( p == NULL ) {
 414         *ludpp = ludp;
 415         return APR_SUCCESS;
 416     }
 417
 418     /* scan forward for '?' that may marks end of dn */
 419     q = strchr( p, '?' );
 420
 421     if( q != NULL ) {
 422         /* terminate dn part */
 423         *q++ = '\0';
 424     }
 425
 426     if( *p != '\0' ) {
 427         /* parse dn part */
 428         apr_ldap_pvt_hex_unescape( p );
 429         ludp->lud_dn = (char *)apr_pstrdup(pool, p);
 430     } else {
 431         ludp->lud_dn = (char *)apr_pstrdup(pool, "");
 432     }
 433
 434     if( ludp->lud_dn == NULL ) {
 435         result->reason = "Out of memory parsing LDAP URL.";
 436         result->rc = APR_LDAP_URL_ERR_MEM;
 437         return APR_EGENERAL;
 438     }
 439
 440     if( q == NULL ) {
 441         /* no more */
 442         *ludpp = ludp;
 443         return APR_SUCCESS;
 444     }
 445
 446     /* scan forward for '?' that may marks end of attributes */
 447     p = q;
 448     q = strchr( p, '?' );
 449
 450     if( q != NULL ) {
 451         /* terminate attributes part */
 452         *q++ = '\0';
 453     }
 454
 455     if( *p != '\0' ) {
 456         /* parse attributes */
 457         apr_ldap_pvt_hex_unescape( p );
 458         ludp->lud_attrs = apr_ldap_str2charray(pool, p, ",");
 459
 460         if( ludp->lud_attrs == NULL ) {
 461             result->reason = "Bad attributes encountered while parsing LDAP URL.";
 462             result->rc = APR_LDAP_URL_ERR_BADATTRS;
 463             return APR_EGENERAL;
 464         }
 465     }
 466
 467     if ( q == NULL ) {
 468         /* no more */
 469         *ludpp = ludp;
 470         return APR_SUCCESS;
 471     }
 472
 473     /* scan forward for '?' that may marks end of scope */
 474     p = q;
 475     q = strchr( p, '?' );
 476
 477     if( q != NULL ) {
 478         /* terminate the scope part */
 479         *q++ = '\0';
 480     }
 481
 482     if( *p != '\0' ) {
 483         /* parse the scope */
 484         apr_ldap_pvt_hex_unescape( p );
 485         ludp->lud_scope = str2scope( p );
 486
 487         if( ludp->lud_scope == -1 ) {
 488             result->reason = "Bad scope encountered while parsing LDAP URL.";
 489             result->rc = APR_LDAP_URL_ERR_BADSCOPE;
 490             return APR_EGENERAL;
 491         }
 492     }
 493
 494     if ( q == NULL ) {
 495         /* no more */
 496         *ludpp = ludp;
 497         return APR_SUCCESS;
 498     }
 499
 500     /* scan forward for '?' that may marks end of filter */
 501     p = q;
 502     q = strchr( p, '?' );
 503
 504     if( q != NULL ) {
 505         /* terminate the filter part */
 506         *q++ = '\0';
 507     }
 508
 509     if( *p != '\0' ) {
 510         /* parse the filter */
 511         apr_ldap_pvt_hex_unescape( p );
 512
 513         if( ! *p ) {
 514             /* missing filter */
 515             result->reason = "Bad filter encountered while parsing LDAP URL.";
 516             result->rc = APR_LDAP_URL_ERR_BADFILTER;
 517             return APR_EGENERAL;
 518         }
 519
 520         ludp->lud_filter = (char *)apr_pstrdup(pool, p);
 521         if( ludp->lud_filter == NULL ) {
 522             result->reason = "Out of memory parsing LDAP URL.";
 523             result->rc = APR_LDAP_URL_ERR_MEM;
 524             return APR_EGENERAL;
 525         }
 526     }
 527
 528     if ( q == NULL ) {
 529         /* no more */
 530         *ludpp = ludp;
 531         return APR_SUCCESS;
 532     }
 533
 534     /* scan forward for '?' that may marks end of extensions */
 535     p = q;
 536     q = strchr( p, '?' );
 537
 538     if( q != NULL ) {
 539         /* extra '?' */
 540         result->reason = "Bad URL encountered while parsing LDAP URL.";
 541         result->rc = APR_LDAP_URL_ERR_BADURL;
 542         return APR_EGENERAL;
 543     }
 544
 545     /* parse the extensions */
 546     ludp->lud_exts = apr_ldap_str2charray(pool, p, ",");
 547     if( ludp->lud_exts == NULL ) {
 548         result->reason = "Bad extensions encountered while parsing LDAP URL.";
 549         result->rc = APR_LDAP_URL_ERR_BADEXTS;
 550         return APR_EGENERAL;
 551     }
 552
 553     for( i=0; ludp->lud_exts[i] != NULL; i++ ) {
 554         apr_ldap_pvt_hex_unescape( ludp->lud_exts[i] );
 555
 556         if( *ludp->lud_exts[i] == '!' ) {
 557             /* count the number of critical extensions */
 558             ludp->lud_crit_exts++;
 559         }
 560     }
 561
 562     if( i == 0 ) {
 563         /* must have 1 or more */
 564         result->reason = "Bad extensions encountered while parsing LDAP URL.";
 565         result->rc = APR_LDAP_URL_ERR_BADEXTS;
 566         return APR_EGENERAL;
 567     }
 568
 569     /* no more */
 570     *ludpp = ludp;
 571     return APR_SUCCESS;
 572 }
 573
 574
 575 /**
 576  * Parse the URL provided into an apr_ldap_url_desc_t object.
 577  *
 578  * APR_SUCCESS is returned on success, APR_EGENERAL on failure.
 579  * The LDAP result code and reason string is returned in the
 580  * apr_ldap_err_t structure.
 581  */
 582 APU_DECLARE(int) apr_ldap_url_parse(apr_pool_t *pool,
 583                                     const char *url_in,
 584                                     apr_ldap_url_desc_t **ludpp,
 585                                     apr_ldap_err_t **result_err)
 586 {
 587
 588     int rc = apr_ldap_url_parse_ext(pool, url_in, ludpp, result_err);
 589     if( rc != APR_SUCCESS ) {
 590         return rc;
 591     }
 592
 593     if ((*ludpp)->lud_scope == -1) {
 594         (*ludpp)->lud_scope = LDAP_SCOPE_BASE;
 595     }
 596
 597     if ((*ludpp)->lud_host != NULL && *(*ludpp)->lud_host == '\0') {
 598         (*ludpp)->lud_host = NULL;
 599     }
 600
 601     return rc;
 602
 603 }
 604
 605
 606 static void apr_ldap_pvt_hex_unescape(char *s)
 607 {
 608     /*
 609      * Remove URL hex escapes from s... done in place.  The basic concept for
 610      * this routine is borrowed from the WWW library HTUnEscape() routine.
 611      */
 612     char    *p;
 613
 614     for ( p = s; *s != '\0'; ++s ) {
 615         if ( *s == '%' ) {
 616             if ( *++s == '\0' ) {
 617                 break;
 618             }
 619             *p = apr_ldap_pvt_unhex( *s ) << 4;
 620             if ( *++s == '\0' ) {
 621                 break;
 622             }
 623             *p++ += apr_ldap_pvt_unhex( *s );
 624         } else {
 625             *p++ = *s;
 626         }
 627     }
 628
 629     *p = '\0';
 630 }
 631
 632
 633 static int apr_ldap_pvt_unhex(int c)
 634 {
 635     return( c >= '0' && c <= '9' ? c - '0'
 636         : c >= 'A' && c <= 'F' ? c - 'A' + 10
 637         : c - 'a' + 10 );
 638 }
 639
 640
 641 /**
 642  * Convert a string to a character array
 643  */
 644 static char **apr_ldap_str2charray(apr_pool_t *pool,
 645                                    const char *str_in,
 646                                    const char *brkstr)
 647 {
 648     char    **res;
 649     char    *str, *s;
 650     char    *lasts;
 651     int i;
 652
 653     /* protect the input string from strtok */
 654     str = (char *)apr_pstrdup(pool, str_in);
 655     if( str == NULL ) {
 656         return NULL;
 657     }
 658
 659     i = 1;
 660     for ( s = str; *s; s++ ) {
 661         /* Warning: this strchr was previously ldap_utf8_strchr(), check
 662          * whether this particular code has any charset issues.
 663          */
 664         if ( strchr( brkstr, *s ) != NULL ) {
 665             i++;
 666         }
 667     }
 668
 669     res = (char **) apr_pcalloc(pool, (i + 1) * sizeof(char *));
 670     if( res == NULL ) {
 671         return NULL;
 672     }
 673
 674     i = 0;
 675
 676     for ( s = (char *)apr_strtok( str, brkstr, &lasts );
 677           s != NULL;
 678           s = (char *)apr_strtok( NULL, brkstr, &lasts ) ) {
 679
 680         res[i] = (char *)apr_pstrdup(pool, s);
 681         if(res[i] == NULL) {
 682             return NULL;
 683         }
 684
 685         i++;
 686     }
 687
 688     res[i] = NULL;
 689
 690     return( res );
 691
 692 }
 693
 694 #endif /* APR_HAS_LDAP */