source4/lib/ldb/common/ldb_dn.c

   1 /*
   2    ldb database library
   3
   4    Copyright (C) Simo Sorce 2005
   5
   6      ** NOTE! The following LGPL license applies to the ldb
   7      ** library. This does NOT imply that all of Samba is released
   8      ** under the LGPL
   9
  10    This library is free software; you can redistribute it and/or
  11    modify it under the terms of the GNU Lesser General Public
  12    License as published by the Free Software Foundation; either
  13    version 2 of the License, or (at your option) any later version.
  14
  15    This library is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18    Lesser General Public License for more details.
  19
  20    You should have received a copy of the GNU Lesser General Public
  21    License along with this library; if not, write to the Free Software
  22    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  23 */
  24
  25 /*
  26  *  Name: ldb
  27  *
  28  *  Component: ldb dn explode and utility functions
  29  *
  30  *  Description: - explode a dn into it's own basic elements
  31  *                 and put them in a structure
  32  *               - manipulate ldb_dn structures
  33  *
  34  *  Author: Simo Sorce
  35  */
  36
  37 #include "includes.h"
  38 #include "ldb/include/includes.h"
  39
  40 #define LDB_DN_NULL_FAILED(x) if (!(x)) goto failed
  41
  42 #define LDB_SPECIAL "@SPECIAL"
  43
  44 /**
  45    internal ldb exploded dn structures
  46 */
  47 struct ldb_dn_component {
  48         char *name;
  49         struct ldb_val value;
  50 };
  51
  52 struct ldb_dn {
  53         int comp_num;
  54         struct ldb_dn_component *components;
  55 };
  56
  57 int ldb_dn_is_special(const struct ldb_dn *dn)
  58 {
  59         if (dn == NULL || dn->comp_num != 1) return 0;
  60
  61         return ! strcmp(dn->components[0].name, LDB_SPECIAL);
  62 }
  63
  64 int ldb_dn_check_special(const struct ldb_dn *dn, const char *check)
  65 {
  66         if (dn == NULL || dn->comp_num != 1) return 0;
  67
  68         return ! strcmp((char *)dn->components[0].value.data, check);
  69 }
  70
  71 char *ldb_dn_escape_value(void *mem_ctx, struct ldb_val value)
  72 {
  73         const char *p, *s, *src;
  74         char *d, *dst;
  75         int len;
  76
  77         if (!value.length)
  78                 return NULL;
  79
  80         p = s = src = (const char *)value.data;
  81         len = value.length;
  82
  83         /* allocate destination string, it will be at most 3 times the source */
  84         dst = d = talloc_array(mem_ctx, char, len * 3 + 1);
  85         LDB_DN_NULL_FAILED(dst);
  86
  87         while (p - src < len) {
  88
  89                 p += strcspn(p, ",=\n+<>#;\\\"");
  90
  91                 if (p - src == len) /* found no escapable chars */
  92                         break;
  93
  94                 memcpy(d, s, p - s); /* copy the part of the string before the stop */
  95                 d += (p - s); /* move to current position */
  96
  97                 if (*p) { /* it is a normal escapable character */
  98                         *d++ = '\\';
  99                         *d++ = *p++;
 100                 } else { /* we have a zero byte in the string */
 101                         strncpy(d, "\00", 3); /* escape the zero */
 102                         d = d + 3;
 103                         p++; /* skip the zero */
 104                 }
 105                 s = p; /* move forward */
 106         }
 107
 108         /* copy the last part (with zero) and return */
 109         memcpy(d, s, &src[len] - s + 1);
 110
 111         return dst;
 112
 113 failed:
 114         talloc_free(dst);
 115         return NULL;
 116 }
 117
 118 static struct ldb_val ldb_dn_unescape_value(void *mem_ctx, const char *src)
 119 {
 120         struct ldb_val value;
 121         unsigned x;
 122         char *p, *dst = NULL, *end;
 123
 124         memset(&value, 0, sizeof(value));
 125
 126         LDB_DN_NULL_FAILED(src);
 127
 128         dst = p = (char *)talloc_memdup(mem_ctx, src, strlen(src) + 1);
 129         LDB_DN_NULL_FAILED(dst);
 130
 131         end = &dst[strlen(dst)];
 132
 133         while (*p) {
 134                 p += strcspn(p, ",=\n+<>#;\\\"");
 135
 136                 if (*p == '\\') {
 137                         if (strchr(",=\n+<>#;\\\"", p[1])) {
 138                                 memmove(p, p + 1, end - (p + 1) + 1);
 139                                 end--;
 140                                 p++;
 141                                 continue;
 142                         }
 143
 144                         if (sscanf(p + 1, "%02x", &x) == 1) {
 145                                 *p = (unsigned char)x;
 146                                 memmove(p + 1, p + 3, end - (p + 3) + 1);
 147                                 end -= 2;
 148                                 p++;
 149                                 continue;
 150                         }
 151                 }
 152
 153                 /* a string with not escaped specials is invalid (tested) */
 154                 if (*p != '\0') {
 155                         goto failed;
 156                 }
 157         }
 158
 159         value.length = end - dst;
 160         value.data = (uint8_t *)dst;
 161         return value;
 162
 163 failed:
 164         talloc_free(dst);
 165         return value;
 166 }
 167
 168 /* check if the string contains quotes
 169  * skips leading and trailing spaces
 170  * - returns 0 if no quotes found
 171  * - returns 1 if quotes are found and put their position
 172  *   in *quote_start and *quote_end parameters
 173  * - return -1 if there are open quotes
 174  */
 175
 176 static int get_quotes_position(const char *source, int *quote_start, int *quote_end)
 177 {
 178         const char *p;
 179
 180         if (source == NULL || quote_start == NULL || quote_end == NULL) return -1;
 181
 182         p = source;
 183
 184         /* check if there are quotes surrounding the value */
 185         p += strspn(p, " \n"); /* skip white spaces */
 186
 187         if (*p == '\"') {
 188                 *quote_start = p - source;
 189
 190                 p++;
 191                 while (*p != '\"') {
 192                         p = strchr(p, '\"');
 193                         LDB_DN_NULL_FAILED(p);
 194
 195                         if (*(p - 1) == '\\')
 196                                 p++;
 197                 }
 198
 199                 *quote_end = p - source;
 200                 return 1;
 201         }
 202
 203         return 0;
 204
 205 failed:
 206         return -1;
 207 }
 208
 209 static char *seek_to_separator(char *string, const char *separators)
 210 {
 211         char *p, *q;
 212         int ret, qs, qe, escaped;
 213
 214         if (string == NULL || separators == NULL) return NULL;
 215
 216         p = strchr(string, '=');
 217         LDB_DN_NULL_FAILED(p);
 218
 219         p++;
 220
 221         /* check if there are quotes surrounding the value */
 222
 223         ret = get_quotes_position(p, &qs, &qe);
 224         if (ret == -1)
 225                 return NULL;
 226
 227         if (ret == 1) { /* quotes found */
 228
 229                 p += qe; /* positioning after quotes */
 230                 p += strspn(p, " \n"); /* skip white spaces after the quote */
 231
 232                 if (strcspn(p, separators) != 0) /* if there are characters between quotes */
 233                         return NULL;        /* and separators, the dn is invalid */
 234
 235                 return p; /* return on the separator */
 236         }
 237
 238         /* no quotes found seek to separators */
 239         q = p;
 240         do {
 241                 escaped = 0;
 242                 ret = strcspn(q, separators);
 243
 244                 if (q[ret - 1] == '\\') {
 245                         escaped = 1;
 246                         q = q + ret + 1;
 247                 }
 248         } while (escaped);
 249
 250         if (ret == 0 && p == q) /* no separators ?! bail out */
 251                 return NULL;
 252
 253         return q + ret;
 254
 255 failed:
 256         return NULL;
 257 }
 258
 259 static char *ldb_dn_trim_string(char *string, const char *edge)
 260 {
 261         char *s, *p;
 262
 263         /* seek out edge from start of string */
 264         s = string + strspn(string, edge);
 265
 266         /* backwards skip from end of string */
 267         p = &s[strlen(s) - 1];
 268         while (p > s && strchr(edge, *p)) {
 269                 *p = '\0';
 270                 p--;
 271         }
 272
 273         return s;
 274 }
 275
 276 /* we choosed to not support multpile valued components */
 277 static struct ldb_dn_component ldb_dn_explode_component(void *mem_ctx, char *raw_component)
 278 {
 279         struct ldb_dn_component dc;
 280         char *p;
 281         int ret, qs, qe;
 282
 283         memset(&dc, 0, sizeof(dc));
 284
 285         if (raw_component == NULL) {
 286                 return dc;
 287         }
 288
 289         /* find attribute type/value separator */
 290         p = strchr(raw_component, '=');
 291         LDB_DN_NULL_FAILED(p);
 292
 293         *p++ = '\0'; /* terminate name and point to value */
 294
 295         /* copy and trim name in the component */
 296         dc.name = talloc_strdup(mem_ctx, ldb_dn_trim_string(raw_component, " \n"));
 297         if (!dc.name)
 298                 return dc;
 299
 300         if (! ldb_valid_attr_name(dc.name)) {
 301                 goto failed;
 302         }
 303
 304         ret = get_quotes_position(p, &qs, &qe);
 305
 306         switch (ret) {
 307         case 0: /* no quotes trim the string */
 308                 p = ldb_dn_trim_string(p, " \n");
 309                 dc.value = ldb_dn_unescape_value(mem_ctx, p);
 310                 break;
 311
 312         case 1: /* quotes found get the unquoted string */
 313                 p[qe] = '\0';
 314                 p = p + qs + 1;
 315                 dc.value.length = strlen(p);
 316                 dc.value.data = (uint8_t *)talloc_memdup(mem_ctx, p,
 317                                                          dc.value.length + 1);
 318                 break;
 319
 320         default: /* mismatched quotes ot other error, bail out */
 321                 goto failed;
 322         }
 323
 324         if (dc.value.length == 0) {
 325                 goto failed;
 326         }
 327
 328         return dc;
 329
 330 failed:
 331         talloc_free(dc.name);
 332         dc.name = NULL;
 333         return dc;
 334 }
 335
 336 struct ldb_dn *ldb_dn_new(void *mem_ctx)
 337 {
 338         struct ldb_dn *edn;
 339
 340         edn = talloc(mem_ctx, struct ldb_dn);
 341         LDB_DN_NULL_FAILED(edn);
 342
 343         /* Initially there are no components */
 344         edn->comp_num = 0;
 345         edn->components = NULL;
 346
 347         return edn;
 348
 349 failed:
 350         return NULL;
 351 }
 352
 353 /*
 354   explode a DN string into a ldb_dn structure
 355 */
 356 struct ldb_dn *ldb_dn_explode(void *mem_ctx, const char *dn)
 357 {
 358         struct ldb_dn *edn; /* the exploded dn */
 359         char *pdn, *p;
 360
 361         if (dn == NULL) return NULL;
 362
 363         /* Allocate a structure to hold the exploded DN */
 364         edn = ldb_dn_new(mem_ctx);
 365         if (edn == NULL) {
 366                 return NULL;
 367         }
 368
 369         pdn = NULL;
 370
 371         /* Empty DNs */
 372         if (dn[0] == '\0') {
 373                 return edn;
 374         }
 375
 376         /* Special DNs case */
 377         if (dn[0] == '@') {
 378                 edn->comp_num = 1;
 379                 edn->components = talloc(edn, struct ldb_dn_component);
 380                 if (edn->components == NULL) goto failed;
 381                 edn->components[0].name = talloc_strdup(edn->components, LDB_SPECIAL);
 382                 if (edn->components[0].name == NULL) goto failed;
 383                 edn->components[0].value.data = (uint8_t *)talloc_strdup(edn->components, dn);
 384                 if (edn->components[0].value.data== NULL) goto failed;
 385                 edn->components[0].value.length = strlen(dn);
 386                 return edn;
 387         }
 388
 389         pdn = p = talloc_strdup(edn, dn);
 390         LDB_DN_NULL_FAILED(pdn);
 391
 392         /* get the components */
 393         do {
 394                 char *t;
 395
 396                 /* terminate the current component and return pointer to the next one */
 397                 t = seek_to_separator(p, ",;");
 398                 LDB_DN_NULL_FAILED(t);
 399
 400                 if (*t) { /* here there is a separator */
 401                         *t = '\0'; /*terminate */
 402                         t++; /* a separtor means another component follows */
 403                 }
 404
 405                 /* allocate space to hold the dn component */
 406                 edn->components = talloc_realloc(edn, edn->components,
 407                                                  struct ldb_dn_component,
 408                                                  edn->comp_num + 1);
 409                 if (edn->components == NULL)
 410                         goto failed;
 411
 412                 /* store the exploded component in the main structure */
 413                 edn->components[edn->comp_num] = ldb_dn_explode_component(edn, p);
 414                 LDB_DN_NULL_FAILED(edn->components[edn->comp_num].name);
 415
 416                 edn->comp_num++;
 417
 418                 /* jump to the next component if any */
 419                 p = t;
 420
 421         } while(*p);
 422
 423         talloc_free(pdn);
 424         return edn;
 425
 426 failed:
 427         talloc_free(pdn);
 428         talloc_free(edn);
 429         return NULL;
 430 }
 431
 432 struct ldb_dn *ldb_dn_explode_or_special(void *mem_ctx, const char *dn)
 433 {
 434         struct ldb_dn *edn; /* the exploded dn */
 435
 436         if (dn == NULL) return NULL;
 437
 438         if (strncasecmp(dn, "<GUID=", 6) == 0) {
 439                 /* this is special DN returned when the
 440                  * exploded_dn control is used
 441                  */
 442
 443                 /* Allocate a structure to hold the exploded DN */
 444                 edn = ldb_dn_new(mem_ctx);
 445
 446                 edn->comp_num = 1;
 447                 edn->components = talloc(edn, struct ldb_dn_component);
 448                 if (edn->components == NULL) goto failed;
 449                 edn->components[0].name = talloc_strdup(edn->components, LDB_SPECIAL);
 450                 if (edn->components[0].name == NULL) goto failed;
 451                 edn->components[0].value.data = (uint8_t *)talloc_strdup(edn->components, dn);
 452                 if (edn->components[0].value.data== NULL) goto failed;
 453                 edn->components[0].value.length = strlen(dn);
 454                 return edn;
 455
 456         }
 457
 458         return ldb_dn_explode(mem_ctx, dn);
 459
 460 failed:
 461         talloc_free(edn);
 462         return NULL;
 463 }
 464
 465 char *ldb_dn_linearize(void *mem_ctx, const struct ldb_dn *edn)
 466 {
 467         char *dn, *value;
 468         int i;
 469
 470         if (edn == NULL) return NULL;
 471
 472         /* Special DNs */
 473         if (ldb_dn_is_special(edn)) {
 474                 dn = talloc_strdup(mem_ctx, (char *)edn->components[0].value.data);
 475                 return dn;
 476         }
 477
 478         dn = talloc_strdup(mem_ctx, "");
 479         LDB_DN_NULL_FAILED(dn);
 480
 481         for (i = 0; i < edn->comp_num; i++) {
 482                 value = ldb_dn_escape_value(dn, edn->components[i].value);
 483                 LDB_DN_NULL_FAILED(value);
 484
 485                 if (i == 0) {
 486                         dn = talloc_asprintf_append(dn, "%s=%s", edn->components[i].name, value);
 487                 } else {
 488                         dn = talloc_asprintf_append(dn, ",%s=%s", edn->components[i].name, value);
 489                 }
 490                 LDB_DN_NULL_FAILED(dn);
 491
 492                 talloc_free(value);
 493         }
 494
 495         return dn;
 496
 497 failed:
 498         talloc_free(dn);
 499         return NULL;
 500 }
 501
 502 /* Determine if dn is below base, in the ldap tree.  Used for
 503  * evaluating a subtree search.
 504  * 0 if they match, otherwise non-zero
 505  */
 506
 507 int ldb_dn_compare_base(struct ldb_context *ldb,
 508                         const struct ldb_dn *base,
 509                         const struct ldb_dn *dn)
 510 {
 511         int ret;
 512         int n0, n1;
 513
 514         if (base == NULL || base->comp_num == 0) return 0;
 515         if (dn == NULL || dn->comp_num == 0) return -1;
 516
 517         /* if the base has more componts than the dn, then they differ */
 518         if (base->comp_num > dn->comp_num) {
 519                 return (dn->comp_num - base->comp_num);
 520         }
 521
 522         n0 = base->comp_num - 1;
 523         n1 = dn->comp_num - 1;
 524         while (n0 >= 0 && n1 >= 0) {
 525                 const struct ldb_attrib_handler *h;
 526
 527                 /* compare names (attribute names are guaranteed to be ASCII only) */
 528                 ret = ldb_attr_cmp(base->components[n0].name,
 529                                    dn->components[n1].name);
 530                 if (ret) {
 531                         return ret;
 532                 }
 533
 534                 /* names match, compare values */
 535                 h = ldb_attrib_handler(ldb, base->components[n0].name);
 536                 ret = h->comparison_fn(ldb, ldb, &(base->components[n0].value),
 537                                                   &(dn->components[n1].value));
 538                 if (ret) {
 539                         return ret;
 540                 }
 541                 n1--;
 542                 n0--;
 543         }
 544
 545         return 0;
 546 }
 547
 548 /* compare DNs using casefolding compare functions.
 549
 550    If they match, then return 0
 551  */
 552
 553 int ldb_dn_compare(struct ldb_context *ldb,
 554                    const struct ldb_dn *edn0,
 555                    const struct ldb_dn *edn1)
 556 {
 557         if (edn0 == NULL || edn1 == NULL) return edn1 - edn0;
 558
 559         if (edn0->comp_num != edn1->comp_num)
 560                 return (edn1->comp_num - edn0->comp_num);
 561
 562         return ldb_dn_compare_base(ldb, edn0, edn1);
 563 }
 564
 565 int ldb_dn_cmp(struct ldb_context *ldb, const char *dn0, const char *dn1)
 566 {
 567         struct ldb_dn *edn0;
 568         struct ldb_dn *edn1;
 569         int ret;
 570
 571         if (dn0 == NULL || dn1 == NULL) return dn1 - dn0;
 572
 573         edn0 = ldb_dn_explode_casefold(ldb, ldb, dn0);
 574         if (edn0 == NULL) return 1;
 575
 576         edn1 = ldb_dn_explode_casefold(ldb, ldb, dn1);
 577         if (edn1 == NULL) {
 578                 talloc_free(edn0);
 579                 return -1;
 580         }
 581
 582         ret = ldb_dn_compare(ldb, edn0, edn1);
 583
 584         talloc_free(edn0);
 585         talloc_free(edn1);
 586
 587         return ret;
 588 }
 589
 590 /*
 591   casefold a dn. We need to casefold the attribute names, and canonicalize
 592   attribute values of case insensitive attributes.
 593 */
 594 struct ldb_dn *ldb_dn_casefold(struct ldb_context *ldb, void *mem_ctx, const struct ldb_dn *edn)
 595 {
 596         struct ldb_dn *cedn;
 597         int i, ret;
 598
 599         if (edn == NULL) return NULL;
 600
 601         cedn = ldb_dn_new(mem_ctx);
 602         if (!cedn) {
 603                 return NULL;
 604         }
 605
 606         cedn->comp_num = edn->comp_num;
 607         cedn->components = talloc_array(cedn, struct ldb_dn_component, edn->comp_num);
 608         if (!cedn->components) {
 609                 talloc_free(cedn);
 610                 return NULL;
 611         }
 612
 613         for (i = 0; i < edn->comp_num; i++) {
 614                 struct ldb_dn_component dc;
 615                 const struct ldb_attrib_handler *h;
 616
 617                 memset(&dc, 0, sizeof(dc));
 618                 dc.name = ldb_attr_casefold(cedn->components, edn->components[i].name);
 619                 if (!dc.name) {
 620                         talloc_free(cedn);
 621                         return NULL;
 622                 }
 623
 624                 h = ldb_attrib_handler(ldb, dc.name);
 625                 ret = h->canonicalise_fn(ldb, cedn->components,
 626                                          &(edn->components[i].value),
 627                                          &(dc.value));
 628                 if (ret != 0) {
 629                         talloc_free(cedn);
 630                         return NULL;
 631                 }
 632
 633                 cedn->components[i] = dc;
 634         }
 635
 636         return cedn;
 637 }
 638
 639 struct ldb_dn *ldb_dn_explode_casefold(struct ldb_context *ldb, void *mem_ctx, const char *dn)
 640 {
 641         struct ldb_dn *edn, *cdn;
 642
 643         if (dn == NULL) return NULL;
 644
 645         edn = ldb_dn_explode(ldb, dn);
 646         if (edn == NULL) return NULL;
 647
 648         cdn = ldb_dn_casefold(ldb, mem_ctx, edn);
 649
 650         talloc_free(edn);
 651         return cdn;
 652 }
 653
 654 char *ldb_dn_linearize_casefold(struct ldb_context *ldb, void *mem_ctx, const struct ldb_dn *edn)
 655 {
 656         struct ldb_dn *cdn;
 657         char *dn;
 658
 659         if (edn == NULL) return NULL;
 660
 661         /* Special DNs */
 662         if (ldb_dn_is_special(edn)) {
 663                 dn = talloc_strdup(mem_ctx, (char *)edn->components[0].value.data);
 664                 return dn;
 665         }
 666
 667         cdn = ldb_dn_casefold(ldb, mem_ctx, edn);
 668         if (cdn == NULL) return NULL;
 669
 670         dn = ldb_dn_linearize(ldb, cdn);
 671         if (dn == NULL) {
 672                 talloc_free(cdn);
 673                 return NULL;
 674         }
 675
 676         talloc_free(cdn);
 677         return dn;
 678 }
 679
 680 static struct ldb_dn_component ldb_dn_copy_component(void *mem_ctx, struct ldb_dn_component *src)
 681 {
 682         struct ldb_dn_component dst;
 683
 684         memset(&dst, 0, sizeof(dst));
 685
 686         if (src == NULL) {
 687                 return dst;
 688         }
 689
 690         dst.value = ldb_val_dup(mem_ctx, &(src->value));
 691         if (dst.value.data == NULL) {
 692                 return dst;
 693         }
 694
 695         dst.name = talloc_strdup(mem_ctx, src->name);
 696         if (dst.name == NULL) {
 697                 talloc_free(dst.value.data);
 698                 dst.value.data = NULL;
 699         }
 700
 701         return dst;
 702 }
 703
 704 /* Copy a DN but replace the old with the new base DN. */
 705 struct ldb_dn *ldb_dn_copy_rebase(void *mem_ctx, const struct ldb_dn *old, const struct ldb_dn *old_base, const struct ldb_dn *new_base)
 706 {
 707         struct ldb_dn *new;
 708         int i, offset;
 709
 710         /* Perhaps we don't need to rebase at all? */
 711         if (!old_base || !new_base) {
 712                 return ldb_dn_copy(mem_ctx, old);
 713         }
 714
 715         offset = old->comp_num - old_base->comp_num;
 716         new = ldb_dn_copy_partial(mem_ctx, new_base, offset + new_base->comp_num);
 717         for (i = 0; i < offset; i++) {
 718                 new->components[i] = ldb_dn_copy_component(new->components, &(old->components[i]));
 719         }
 720
 721         return new;
 722 }
 723
 724 /* copy specified number of elements of a dn into a new one
 725    element are copied from top level up to the unique rdn
 726    num_el may be greater than dn->comp_num (see ldb_dn_make_child)
 727 */
 728 struct ldb_dn *ldb_dn_copy_partial(void *mem_ctx, const struct ldb_dn *dn, int num_el)
 729 {
 730         struct ldb_dn *newdn;
 731         int i, n, e;
 732
 733         if (dn == NULL) return NULL;
 734         if (num_el <= 0) return NULL;
 735
 736         newdn = ldb_dn_new(mem_ctx);
 737         LDB_DN_NULL_FAILED(newdn);
 738
 739         newdn->comp_num = num_el;
 740         n = newdn->comp_num - 1;
 741         newdn->components = talloc_array(newdn, struct ldb_dn_component, newdn->comp_num);
 742         if (newdn->components == NULL) goto failed;
 743
 744         if (dn->comp_num == 0) return newdn;
 745         e = dn->comp_num - 1;
 746
 747         for (i = 0; i < newdn->comp_num; i++) {
 748                 newdn->components[n - i] = ldb_dn_copy_component(newdn->components,
 749                                                                 &(dn->components[e - i]));
 750                 if ((e - i) == 0) {
 751                         return newdn;
 752                 }
 753         }
 754
 755         return newdn;
 756
 757 failed:
 758         talloc_free(newdn);
 759         return NULL;
 760 }
 761
 762 struct ldb_dn *ldb_dn_copy(void *mem_ctx, const struct ldb_dn *dn)
 763 {
 764         if (dn == NULL) return NULL;
 765         return ldb_dn_copy_partial(mem_ctx, dn, dn->comp_num);
 766 }
 767
 768 struct ldb_dn *ldb_dn_get_parent(void *mem_ctx, const struct ldb_dn *dn)
 769 {
 770         if (dn == NULL) return NULL;
 771         return ldb_dn_copy_partial(mem_ctx, dn, dn->comp_num - 1);
 772 }
 773
 774 struct ldb_dn_component *ldb_dn_build_component(void *mem_ctx, const char *attr,
 775                                                 const char *val)
 776 {
 777         struct ldb_dn_component *dc;
 778
 779         if (attr == NULL || val == NULL) return NULL;
 780
 781         dc = talloc(mem_ctx, struct ldb_dn_component);
 782         if (dc == NULL) return NULL;
 783
 784         dc->name = talloc_strdup(dc, attr);
 785         if (dc->name ==  NULL) {
 786                 talloc_free(dc);
 787                 return NULL;
 788         }
 789
 790         dc->value.data = (uint8_t *)talloc_strdup(dc, val);
 791         if (dc->value.data ==  NULL) {
 792                 talloc_free(dc);
 793                 return NULL;
 794         }
 795
 796         dc->value.length = strlen(val);
 797
 798         return dc;
 799 }
 800
 801 struct ldb_dn *ldb_dn_build_child(void *mem_ctx, const char *attr,
 802                                                  const char * value,
 803                                                  const struct ldb_dn *base)
 804 {
 805         struct ldb_dn *newdn;
 806         if (! ldb_valid_attr_name(attr)) return NULL;
 807         if (value == NULL || value == '\0') return NULL;
 808
 809         if (base != NULL) {
 810                 newdn = ldb_dn_copy_partial(mem_ctx, base, base->comp_num + 1);
 811                 LDB_DN_NULL_FAILED(newdn);
 812         } else {
 813                 newdn = ldb_dn_new(mem_ctx);
 814                 LDB_DN_NULL_FAILED(newdn);
 815
 816                 newdn->comp_num = 1;
 817                 newdn->components = talloc_array(newdn, struct ldb_dn_component, newdn->comp_num);
 818         }
 819
 820         newdn->components[0].name = talloc_strdup(newdn->components, attr);
 821         LDB_DN_NULL_FAILED(newdn->components[0].name);
 822
 823         newdn->components[0].value.data = (uint8_t *)talloc_strdup(newdn->components, value);
 824         LDB_DN_NULL_FAILED(newdn->components[0].value.data);
 825         newdn->components[0].value.length = strlen((char *)newdn->components[0].value.data);
 826
 827         return newdn;
 828
 829 failed:
 830         talloc_free(newdn);
 831         return NULL;
 832
 833 }
 834
 835 struct ldb_dn *ldb_dn_compose(void *mem_ctx, const struct ldb_dn *dn1, const struct ldb_dn *dn2)
 836 {
 837         int i;
 838         struct ldb_dn *newdn;
 839
 840         if (dn2 == NULL && dn1 == NULL) {
 841                 return NULL;
 842         }
 843
 844         if (dn2 == NULL) {
 845                 newdn = ldb_dn_new(mem_ctx);
 846                 LDB_DN_NULL_FAILED(newdn);
 847
 848                 newdn->comp_num = dn1->comp_num;
 849                 newdn->components = talloc_array(newdn, struct ldb_dn_component, newdn->comp_num);
 850         } else {
 851                 int comp_num = dn2->comp_num;
 852                 if (dn1 != NULL) comp_num += dn1->comp_num;
 853                 newdn = ldb_dn_copy_partial(mem_ctx, dn2, comp_num);
 854                 LDB_DN_NULL_FAILED(newdn);
 855         }
 856
 857         if (dn1 == NULL) {
 858                 return newdn;
 859         }
 860
 861         for (i = 0; i < dn1->comp_num; i++) {
 862                 newdn->components[i] = ldb_dn_copy_component(newdn->components,
 863                                                            &(dn1->components[i]));
 864                 if (newdn->components[i].value.data == NULL) {
 865                         goto failed;
 866                 }
 867         }
 868
 869         return newdn;
 870
 871 failed:
 872         talloc_free(newdn);
 873         return NULL;
 874 }
 875
 876 struct ldb_dn *ldb_dn_string_compose(void *mem_ctx, const struct ldb_dn *base, const char *child_fmt, ...)
 877 {
 878         struct ldb_dn *dn, *dn1;
 879         char *child_str;
 880         va_list ap;
 881
 882         if (child_fmt == NULL) return NULL;
 883
 884         va_start(ap, child_fmt);
 885         child_str = talloc_vasprintf(mem_ctx, child_fmt, ap);
 886         va_end(ap);
 887
 888         if (child_str == NULL) return NULL;
 889
 890         dn1 = ldb_dn_explode(mem_ctx, child_str);
 891         dn = ldb_dn_compose(mem_ctx, dn1, base);
 892
 893         talloc_free(child_str);
 894         talloc_free(dn1);
 895
 896         return dn;
 897 }
 898
 899 /* Create a 'canonical name' string from a DN:
 900
 901    ie dc=samba,dc=org -> samba.org/
 902       uid=administrator,ou=users,dc=samba,dc=org = samba.org/users/administrator
 903
 904    There are two formats, the EX format has the last / replaced with a newline (\n).
 905
 906 */
 907 static char *ldb_dn_canonical(void *mem_ctx, const struct ldb_dn *dn, int ex_format) {
 908         int i;
 909         char *cracked = NULL;
 910
 911         /* Walk backwards down the DN, grabbing 'dc' components at first */
 912         for (i = dn->comp_num - 1 ; i >= 0; i--) {
 913                 if (ldb_attr_cmp(dn->components[i].name, "dc") != 0) {
 914                         break;
 915                 }
 916                 if (cracked) {
 917                         cracked = talloc_asprintf(mem_ctx, "%s.%s",
 918                                                   ldb_dn_escape_value(mem_ctx, dn->components[i].value),
 919                                                   cracked);
 920                 } else {
 921                         cracked = ldb_dn_escape_value(mem_ctx, dn->components[i].value);
 922                 }
 923                 if (!cracked) {
 924                         return NULL;
 925                 }
 926         }
 927
 928         /* Only domain components?  Finish here */
 929         if (i < 0) {
 930                 if (ex_format) {
 931                         cracked = talloc_asprintf(mem_ctx, "%s\n", cracked);
 932                 } else {
 933                         cracked = talloc_asprintf(mem_ctx, "%s/", cracked);
 934                 }
 935                 return cracked;
 936         }
 937
 938         /* Now walk backwards appending remaining components */
 939         for (; i > 0; i--) {
 940                 cracked = talloc_asprintf(mem_ctx, "%s/%s", cracked,
 941                                           ldb_dn_escape_value(mem_ctx, dn->components[i].value));
 942                 if (!cracked) {
 943                         return NULL;
 944                 }
 945         }
 946
 947         /* Last one, possibly a newline for the 'ex' format */
 948         if (ex_format) {
 949                 cracked = talloc_asprintf(mem_ctx, "%s\n%s", cracked,
 950                                           ldb_dn_escape_value(mem_ctx, dn->components[i].value));
 951         } else {
 952                 cracked = talloc_asprintf(mem_ctx, "%s/%s", cracked,
 953                                           ldb_dn_escape_value(mem_ctx, dn->components[i].value));
 954         }
 955         return cracked;
 956 }
 957
 958 /* Wrapper functions for the above, for the two different string formats */
 959 char *ldb_dn_canonical_string(void *mem_ctx, const struct ldb_dn *dn) {
 960         return ldb_dn_canonical(mem_ctx, dn, 0);
 961
 962 }
 963
 964 char *ldb_dn_canonical_ex_string(void *mem_ctx, const struct ldb_dn *dn) {
 965         return ldb_dn_canonical(mem_ctx, dn, 1);
 966 }
 967
 968 int ldb_dn_get_comp_num(const struct ldb_dn *dn)
 969 {
 970         return dn->comp_num;
 971 }
 972
 973 const char *ldb_dn_get_component_name(const struct ldb_dn *dn, unsigned int num)
 974 {
 975         if (num >= dn->comp_num) return NULL;
 976         return dn->components[num].name;
 977 }
 978
 979 const struct ldb_val *ldb_dn_get_component_val(const struct ldb_dn *dn, unsigned int num)
 980 {
 981         if (num >= dn->comp_num) return NULL;
 982         return &dn->components[num].value;
 983 }
 984
 985 const char *ldb_dn_get_rdn_name(const struct ldb_dn *dn) {
 986         if (dn->comp_num == 0) return NULL;
 987         return dn->components[0].name;
 988 }
 989
 990 const struct ldb_val *ldb_dn_get_rdn_val(const struct ldb_dn *dn) {
 991         if (dn->comp_num == 0) return NULL;
 992         return &dn->components[0].value;
 993 }
 994
 995 int ldb_dn_set_component(struct ldb_dn *dn, int num, const char *name, const struct ldb_val val)
 996 {
 997         char *n;
 998         struct ldb_val v;
 999
1000         if (num >= dn->comp_num) {
1001                 return LDB_ERR_OTHER;
1002         }
1003
1004         n = talloc_strdup(dn, name);
1005         if ( ! n) {
1006                 return LDB_ERR_OTHER;
1007         }
1008
1009         v.length = val.length;
1010         v.data = (uint8_t *)talloc_memdup(dn, val.data, v.length+1);
1011         if ( ! v.data) {
1012                 return LDB_ERR_OTHER;
1013         }
1014
1015         talloc_free(dn->components[num].name);
1016         talloc_free(dn->components[num].value.data);
1017         dn->components[num].name = n;
1018         dn->components[num].value = v;
1019
1020         return LDB_SUCCESS;
1021 }