git.sur5r.net Git - openldap/blob - servers/slapd/backover.c

   1 /* backover.c - backend overlay routines */
   2 /* $OpenLDAP$ */
   3 /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
   4  *
   5  * Copyright 2003-2015 The OpenLDAP Foundation.
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted only as authorized by the OpenLDAP
  10  * Public License.
  11  *
  12  * A copy of this license is available in the file LICENSE in the
  13  * top-level directory of the distribution or, alternatively, at
  14  * <http://www.OpenLDAP.org/license.html>.
  15  */
  16
  17 /* Functions to overlay other modules over a backend. */
  18
  19 #include "portable.h"
  20
  21 #include <stdio.h>
  22
  23 #include <ac/string.h>
  24 #include <ac/socket.h>
  25
  26 #define SLAPD_TOOLS
  27 #include "slap.h"
  28 #include "config.h"
  29
  30 static slap_overinst *overlays;
  31
  32 static int
  33 over_db_config(
  34         BackendDB *be,
  35         const char *fname,
  36         int lineno,
  37         int argc,
  38         char **argv
  39 )
  40 {
  41         slap_overinfo *oi = be->bd_info->bi_private;
  42         slap_overinst *on = oi->oi_list;
  43         BackendInfo *bi_orig = be->bd_info;
  44         struct ConfigOCs *be_cf_ocs = be->be_cf_ocs;
  45         ConfigArgs ca = {0};
  46         int rc = 0;
  47
  48         if ( oi->oi_orig->bi_db_config ) {
  49                 be->bd_info = oi->oi_orig;
  50                 be->be_cf_ocs = oi->oi_orig->bi_cf_ocs;
  51                 rc = oi->oi_orig->bi_db_config( be, fname, lineno,
  52                         argc, argv );
  53
  54                 if ( be->bd_info != oi->oi_orig ) {
  55                         slap_overinfo   *oi2;
  56                         slap_overinst   *on2, **onp;
  57                         BackendDB       be2 = *be;
  58                         int             i;
  59
  60                         /* a database added an overlay;
  61                          * work it around... */
  62                         assert( overlay_is_over( be ) );
  63
  64                         oi2 = ( slap_overinfo * )be->bd_info->bi_private;
  65                         on2 = oi2->oi_list;
  66
  67                         /* need to put a uniqueness check here as well;
  68                          * note that in principle there could be more than
  69                          * one overlay as a result of multiple calls to
  70                          * overlay_config() */
  71                         be2.bd_info = (BackendInfo *)oi;
  72
  73                         for ( i = 0, onp = &on2; *onp; i++, onp = &(*onp)->on_next ) {
  74                                 if ( overlay_is_inst( &be2, (*onp)->on_bi.bi_type ) ) {
  75                                         Debug( LDAP_DEBUG_ANY, "over_db_config(): "
  76                                                         "warning, freshly added "
  77                                                         "overlay #%d \"%s\" is already in list\n",
  78                                                         i, (*onp)->on_bi.bi_type, 0 );
  79
  80                                         /* NOTE: if the overlay already exists,
  81                                          * there is no way to merge the results
  82                                          * of the configuration that may have
  83                                          * occurred during bi_db_config(); we
  84                                          * just issue a warning, and the
  85                                          * administrator should deal with this */
  86                                 }
  87                         }
  88                         *onp = oi->oi_list;
  89
  90                         oi->oi_list = on2;
  91
  92                         ch_free( be->bd_info );
  93                 }
  94
  95                 be->bd_info = (BackendInfo *)oi;
  96                 if ( rc != SLAP_CONF_UNKNOWN ) return rc;
  97         }
  98
  99         ca.argv = argv;
 100         ca.argc = argc;
 101         ca.fname = fname;
 102         ca.lineno = lineno;
 103         ca.be = be;
 104         snprintf( ca.log, sizeof( ca.log ), "%s: line %d",
 105                         ca.fname, ca.lineno );
 106         ca.op = SLAP_CONFIG_ADD;
 107         ca.valx = -1;
 108
 109         for (; on; on=on->on_next) {
 110                 rc = SLAP_CONF_UNKNOWN;
 111                 if (on->on_bi.bi_cf_ocs) {
 112                         ConfigTable *ct;
 113                         ca.bi = &on->on_bi;
 114                         ct = config_find_keyword( on->on_bi.bi_cf_ocs->co_table, &ca );
 115                         if ( ct ) {
 116                                 ca.table = on->on_bi.bi_cf_ocs->co_type;
 117                                 rc = config_add_vals( ct, &ca );
 118                                 if ( rc != SLAP_CONF_UNKNOWN )
 119                                         break;
 120                         }
 121                 }
 122                 if (on->on_bi.bi_db_config && rc == SLAP_CONF_UNKNOWN) {
 123                         be->bd_info = &on->on_bi;
 124                         rc = on->on_bi.bi_db_config( be, fname, lineno,
 125                                 argc, argv );
 126                         if ( rc != SLAP_CONF_UNKNOWN ) break;
 127                 }
 128         }
 129         be->bd_info = bi_orig;
 130         be->be_cf_ocs = be_cf_ocs;
 131
 132         return rc;
 133 }
 134
 135 static int
 136 over_db_open(
 137         BackendDB *be,
 138         ConfigReply *cr
 139 )
 140 {
 141         slap_overinfo *oi = be->bd_info->bi_private;
 142         slap_overinst *on = oi->oi_list;
 143         BackendDB db = *be;
 144         int rc = 0;
 145
 146         db.be_flags |= SLAP_DBFLAG_OVERLAY;
 147         db.bd_info = oi->oi_orig;
 148         if ( db.bd_info->bi_db_open ) {
 149                 rc = db.bd_info->bi_db_open( &db, cr );
 150         }
 151
 152         for (; on && rc == 0; on=on->on_next) {
 153                 if ( on->on_bi.bi_flags & SLAPO_BFLAG_DISABLED )
 154                         continue;
 155                 db.bd_info = &on->on_bi;
 156                 if ( db.bd_info->bi_db_open ) {
 157                         rc = db.bd_info->bi_db_open( &db, cr );
 158                 }
 159         }
 160
 161         return rc;
 162 }
 163
 164 static int
 165 over_db_close(
 166         BackendDB *be,
 167         ConfigReply *cr
 168 )
 169 {
 170         slap_overinfo *oi = be->bd_info->bi_private;
 171         slap_overinst *on = oi->oi_list;
 172         BackendInfo *bi_orig = be->bd_info;
 173         int rc = 0;
 174
 175         for (; on && rc == 0; on=on->on_next) {
 176                 if ( on->on_bi.bi_flags & SLAPO_BFLAG_DISABLED )
 177                         continue;
 178                 be->bd_info = &on->on_bi;
 179                 if ( be->bd_info->bi_db_close ) {
 180                         rc = be->bd_info->bi_db_close( be, cr );
 181                 }
 182         }
 183
 184         if ( oi->oi_orig->bi_db_close ) {
 185                 be->bd_info = oi->oi_orig;
 186                 rc = be->bd_info->bi_db_close( be, cr );
 187         }
 188
 189         be->bd_info = bi_orig;
 190         return rc;
 191 }
 192
 193 static int
 194 over_db_destroy(
 195         BackendDB *be,
 196         ConfigReply *cr
 197 )
 198 {
 199         slap_overinfo *oi = be->bd_info->bi_private;
 200         slap_overinst *on = oi->oi_list, *next;
 201         BackendInfo *bi_orig = be->bd_info;
 202         int rc = 0;
 203
 204         be->bd_info = oi->oi_orig;
 205         if ( be->bd_info->bi_db_destroy ) {
 206                 rc = be->bd_info->bi_db_destroy( be, cr );
 207         }
 208
 209         for (; on && rc == 0; on=on->on_next) {
 210                 if ( on->on_bi.bi_flags & SLAPO_BFLAG_DISABLED )
 211                         continue;
 212                 be->bd_info = &on->on_bi;
 213                 if ( be->bd_info->bi_db_destroy ) {
 214                         rc = be->bd_info->bi_db_destroy( be, cr );
 215                 }
 216         }
 217
 218         on = oi->oi_list;
 219         if ( on ) {
 220                 for (next = on->on_next; on; on=next) {
 221                         next = on->on_next;
 222                         free( on );
 223                 }
 224         }
 225         be->bd_info = bi_orig;
 226         free( oi );
 227         return rc;
 228 }
 229
 230 static int
 231 over_back_response ( Operation *op, SlapReply *rs )
 232 {
 233         slap_overinfo *oi = op->o_callback->sc_private;
 234         slap_overinst *on = oi->oi_list;
 235         int rc = SLAP_CB_CONTINUE;
 236         BackendDB *be = op->o_bd, db = *op->o_bd;
 237
 238         db.be_flags |= SLAP_DBFLAG_OVERLAY;
 239         op->o_bd = &db;
 240         for (; on; on=on->on_next ) {
 241                 if ( on->on_bi.bi_flags & SLAPO_BFLAG_DISABLED )
 242                         continue;
 243                 if ( on->on_response ) {
 244                         db.bd_info = (BackendInfo *)on;
 245                         rc = on->on_response( op, rs );
 246                         if ( rc != SLAP_CB_CONTINUE ) break;
 247                 }
 248         }
 249         /* Bypass the remaining on_response layers, but allow
 250          * normal execution to continue.
 251          */
 252         if ( rc == SLAP_CB_BYPASS )
 253                 rc = SLAP_CB_CONTINUE;
 254         op->o_bd = be;
 255         return rc;
 256 }
 257
 258 static int
 259 over_access_allowed(
 260         Operation               *op,
 261         Entry                   *e,
 262         AttributeDescription    *desc,
 263         struct berval           *val,
 264         slap_access_t           access,
 265         AccessControlState      *state,
 266         slap_mask_t             *maskp )
 267 {
 268         slap_overinfo *oi;
 269         slap_overinst *on;
 270         BackendInfo *bi;
 271         BackendDB *be = op->o_bd, db;
 272         int rc = SLAP_CB_CONTINUE;
 273
 274         /* FIXME: used to happen for instance during abandon
 275          * when global overlays are used... */
 276         assert( op->o_bd != NULL );
 277
 278         bi = op->o_bd->bd_info;
 279         /* Were we invoked on the frontend? */
 280         if ( !bi->bi_access_allowed ) {
 281                 oi = frontendDB->bd_info->bi_private;
 282         } else {
 283                 oi = op->o_bd->bd_info->bi_private;
 284         }
 285         on = oi->oi_list;
 286
 287         for ( ; on; on = on->on_next ) {
 288                 if ( on->on_bi.bi_flags & SLAPO_BFLAG_DISABLED )
 289                         continue;
 290                 if ( on->on_bi.bi_access_allowed ) {
 291                         /* NOTE: do not copy the structure until required */
 292                         if ( !SLAP_ISOVERLAY( op->o_bd ) ) {
 293                                 db = *op->o_bd;
 294                                 db.be_flags |= SLAP_DBFLAG_OVERLAY;
 295                                 op->o_bd = &db;
 296                         }
 297
 298                         op->o_bd->bd_info = (BackendInfo *)on;
 299                         rc = on->on_bi.bi_access_allowed( op, e,
 300                                 desc, val, access, state, maskp );
 301                         if ( rc != SLAP_CB_CONTINUE ) break;
 302                 }
 303         }
 304
 305         if ( rc == SLAP_CB_CONTINUE ) {
 306                 BI_access_allowed       *bi_access_allowed;
 307
 308                 /* if the database structure was changed, o_bd points to a
 309                  * copy of the structure; put the original bd_info in place */
 310                 if ( SLAP_ISOVERLAY( op->o_bd ) ) {
 311                         op->o_bd->bd_info = oi->oi_orig;
 312                 }
 313
 314                 if ( oi->oi_orig->bi_access_allowed ) {
 315                         bi_access_allowed = oi->oi_orig->bi_access_allowed;
 316                 } else {
 317                         bi_access_allowed = slap_access_allowed;
 318                 }
 319
 320                 rc = bi_access_allowed( op, e,
 321                         desc, val, access, state, maskp );
 322         }
 323         /* should not fall thru this far without anything happening... */
 324         if ( rc == SLAP_CB_CONTINUE ) {
 325                 /* access not allowed */
 326                 rc = 0;
 327         }
 328
 329         op->o_bd = be;
 330         op->o_bd->bd_info = bi;
 331
 332         return rc;
 333 }
 334
 335 int
 336 overlay_entry_get_ov(
 337         Operation               *op,
 338         struct berval   *dn,
 339         ObjectClass             *oc,
 340         AttributeDescription    *ad,
 341         int     rw,
 342         Entry   **e,
 343         slap_overinst *on )
 344 {
 345         slap_overinfo *oi = on->on_info;
 346         BackendDB *be = op->o_bd, db;
 347         BackendInfo *bi = op->o_bd->bd_info;
 348         int rc = SLAP_CB_CONTINUE;
 349
 350         for ( ; on; on = on->on_next ) {
 351                 if ( on->on_bi.bi_flags & SLAPO_BFLAG_DISABLED )
 352                         continue;
 353                 if ( on->on_bi.bi_entry_get_rw ) {
 354                         /* NOTE: do not copy the structure until required */
 355                         if ( !SLAP_ISOVERLAY( op->o_bd ) ) {
 356                                 db = *op->o_bd;
 357                                 db.be_flags |= SLAP_DBFLAG_OVERLAY;
 358                                 op->o_bd = &db;
 359                         }
 360
 361                         op->o_bd->bd_info = (BackendInfo *)on;
 362                         rc = on->on_bi.bi_entry_get_rw( op, dn,
 363                                 oc, ad, rw, e );
 364                         if ( rc != SLAP_CB_CONTINUE ) break;
 365                 }
 366         }
 367
 368         if ( rc == SLAP_CB_CONTINUE ) {
 369                 /* if the database structure was changed, o_bd points to a
 370                  * copy of the structure; put the original bd_info in place */
 371                 if ( SLAP_ISOVERLAY( op->o_bd ) ) {
 372                         op->o_bd->bd_info = oi->oi_orig;
 373                 }
 374
 375                 if ( oi->oi_orig->bi_entry_get_rw ) {
 376                         rc = oi->oi_orig->bi_entry_get_rw( op, dn,
 377                                 oc, ad, rw, e );
 378                 }
 379         }
 380         /* should not fall thru this far without anything happening... */
 381         if ( rc == SLAP_CB_CONTINUE ) {
 382                 rc = LDAP_UNWILLING_TO_PERFORM;
 383         }
 384
 385         op->o_bd = be;
 386         op->o_bd->bd_info = bi;
 387
 388         return rc;
 389 }
 390
 391 static int
 392 over_entry_get_rw(
 393         Operation               *op,
 394         struct berval   *dn,
 395         ObjectClass             *oc,
 396         AttributeDescription    *ad,
 397         int     rw,
 398         Entry   **e )
 399 {
 400         slap_overinfo *oi;
 401         slap_overinst *on;
 402
 403         assert( op->o_bd != NULL );
 404
 405         oi = op->o_bd->bd_info->bi_private;
 406         on = oi->oi_list;
 407
 408         return overlay_entry_get_ov( op, dn, oc, ad, rw, e, on );
 409 }
 410
 411 int
 412 overlay_entry_release_ov(
 413         Operation       *op,
 414         Entry   *e,
 415         int rw,
 416         slap_overinst *on )
 417 {
 418         slap_overinfo *oi = on->on_info;
 419         BackendDB *be = op->o_bd, db;
 420         BackendInfo *bi = op->o_bd->bd_info;
 421         int rc = SLAP_CB_CONTINUE;
 422
 423         for ( ; on; on = on->on_next ) {
 424                 if ( on->on_bi.bi_flags & SLAPO_BFLAG_DISABLED )
 425                         continue;
 426                 if ( on->on_bi.bi_entry_release_rw ) {
 427                         /* NOTE: do not copy the structure until required */
 428                         if ( !SLAP_ISOVERLAY( op->o_bd ) ) {
 429                                 db = *op->o_bd;
 430                                 db.be_flags |= SLAP_DBFLAG_OVERLAY;
 431                                 op->o_bd = &db;
 432                         }
 433
 434                         op->o_bd->bd_info = (BackendInfo *)on;
 435                         rc = on->on_bi.bi_entry_release_rw( op, e, rw );
 436                         if ( rc != SLAP_CB_CONTINUE ) break;
 437                 }
 438         }
 439
 440         if ( rc == SLAP_CB_CONTINUE ) {
 441                 /* if the database structure was changed, o_bd points to a
 442                  * copy of the structure; put the original bd_info in place */
 443                 if ( SLAP_ISOVERLAY( op->o_bd ) ) {
 444                         op->o_bd->bd_info = oi->oi_orig;
 445                 }
 446
 447                 if ( oi->oi_orig->bi_entry_release_rw ) {
 448                         rc = oi->oi_orig->bi_entry_release_rw( op, e, rw );
 449                 }
 450         }
 451         /* should not fall thru this far without anything happening... */
 452         if ( rc == SLAP_CB_CONTINUE ) {
 453                 entry_free( e );
 454                 rc = 0;
 455         }
 456
 457         op->o_bd = be;
 458         op->o_bd->bd_info = bi;
 459
 460         return rc;
 461 }
 462
 463 static int
 464 over_entry_release_rw(
 465         Operation       *op,
 466         Entry   *e,
 467         int rw )
 468 {
 469         slap_overinfo *oi;
 470         slap_overinst *on;
 471
 472         assert( op->o_bd != NULL );
 473
 474         oi = op->o_bd->bd_info->bi_private;
 475         on = oi->oi_list;
 476
 477         return overlay_entry_release_ov( op, e, rw, on );
 478 }
 479
 480 static int
 481 over_acl_group(
 482         Operation               *op,
 483         Entry                   *e,
 484         struct berval           *gr_ndn,
 485         struct berval           *op_ndn,
 486         ObjectClass             *group_oc,
 487         AttributeDescription    *group_at )
 488 {
 489         slap_overinfo *oi;
 490         slap_overinst *on;
 491         BackendInfo *bi;
 492         BackendDB *be = op->o_bd, db;
 493         int rc = SLAP_CB_CONTINUE;
 494
 495         /* FIXME: used to happen for instance during abandon
 496          * when global overlays are used... */
 497         assert( be != NULL );
 498
 499         bi = be->bd_info;
 500         oi = bi->bi_private;
 501         on = oi->oi_list;
 502
 503         for ( ; on; on = on->on_next ) {
 504                 if ( on->on_bi.bi_flags & SLAPO_BFLAG_DISABLED )
 505                         continue;
 506                 if ( on->on_bi.bi_acl_group ) {
 507                         /* NOTE: do not copy the structure until required */
 508                         if ( !SLAP_ISOVERLAY( op->o_bd ) ) {
 509                                 db = *op->o_bd;
 510                                 db.be_flags |= SLAP_DBFLAG_OVERLAY;
 511                                 op->o_bd = &db;
 512                         }
 513
 514                         op->o_bd->bd_info = (BackendInfo *)on;
 515                         rc = on->on_bi.bi_acl_group( op, e,
 516                                 gr_ndn, op_ndn, group_oc, group_at );
 517                         if ( rc != SLAP_CB_CONTINUE ) break;
 518                 }
 519         }
 520
 521         if ( rc == SLAP_CB_CONTINUE ) {
 522                 BI_acl_group            *bi_acl_group;
 523
 524                 /* if the database structure was changed, o_bd points to a
 525                  * copy of the structure; put the original bd_info in place */
 526                 if ( SLAP_ISOVERLAY( op->o_bd ) ) {
 527                         op->o_bd->bd_info = oi->oi_orig;
 528                 }
 529
 530                 if ( oi->oi_orig->bi_acl_group ) {
 531                         bi_acl_group = oi->oi_orig->bi_acl_group;
 532                 } else {
 533                         bi_acl_group = backend_group;
 534                 }
 535
 536                 rc = bi_acl_group( op, e,
 537                         gr_ndn, op_ndn, group_oc, group_at );
 538         }
 539         /* should not fall thru this far without anything happening... */
 540         if ( rc == SLAP_CB_CONTINUE ) {
 541                 /* access not allowed */
 542                 rc = 0;
 543         }
 544
 545         op->o_bd = be;
 546         op->o_bd->bd_info = bi;
 547
 548         return rc;
 549 }
 550
 551 static int
 552 over_acl_attribute(
 553         Operation               *op,
 554         Entry                   *target,
 555         struct berval           *entry_ndn,
 556         AttributeDescription    *entry_at,
 557         BerVarray               *vals,
 558         slap_access_t           access )
 559 {
 560         slap_overinfo *oi;
 561         slap_overinst *on;
 562         BackendInfo *bi;
 563         BackendDB *be = op->o_bd, db;
 564         int rc = SLAP_CB_CONTINUE;
 565
 566         /* FIXME: used to happen for instance during abandon
 567          * when global overlays are used... */
 568         assert( be != NULL );
 569
 570         bi = be->bd_info;
 571         oi = bi->bi_private;
 572         on = oi->oi_list;
 573
 574         for ( ; on; on = on->on_next ) {
 575                 if ( on->on_bi.bi_flags & SLAPO_BFLAG_DISABLED )
 576                         continue;
 577                 if ( on->on_bi.bi_acl_attribute ) {
 578                         /* NOTE: do not copy the structure until required */
 579                         if ( !SLAP_ISOVERLAY( op->o_bd ) ) {
 580                                 db = *op->o_bd;
 581                                 db.be_flags |= SLAP_DBFLAG_OVERLAY;
 582                                 op->o_bd = &db;
 583                         }
 584
 585                         op->o_bd->bd_info = (BackendInfo *)on;
 586                         rc = on->on_bi.bi_acl_attribute( op, target,
 587                                 entry_ndn, entry_at, vals, access );
 588                         if ( rc != SLAP_CB_CONTINUE ) break;
 589                 }
 590         }
 591
 592         if ( rc == SLAP_CB_CONTINUE ) {
 593                 BI_acl_attribute                *bi_acl_attribute;
 594
 595                 /* if the database structure was changed, o_bd points to a
 596                  * copy of the structure; put the original bd_info in place */
 597                 if ( SLAP_ISOVERLAY( op->o_bd ) ) {
 598                         op->o_bd->bd_info = oi->oi_orig;
 599                 }
 600
 601                 if ( oi->oi_orig->bi_acl_attribute ) {
 602                         bi_acl_attribute = oi->oi_orig->bi_acl_attribute;
 603                 } else {
 604                         bi_acl_attribute = backend_attribute;
 605                 }
 606
 607                 rc = bi_acl_attribute( op, target,
 608                         entry_ndn, entry_at, vals, access );
 609         }
 610         /* should not fall thru this far without anything happening... */
 611         if ( rc == SLAP_CB_CONTINUE ) {
 612                 /* access not allowed */
 613                 rc = 0;
 614         }
 615
 616         op->o_bd = be;
 617         op->o_bd->bd_info = bi;
 618
 619         return rc;
 620 }
 621
 622 int
 623 overlay_callback_after_backover( Operation *op, slap_callback *sc, int append )
 624 {
 625         slap_callback **scp;
 626
 627         for ( scp = &op->o_callback; *scp != NULL; scp = &(*scp)->sc_next ) {
 628                 if ( (*scp)->sc_response == over_back_response ) {
 629                         sc->sc_next = (*scp)->sc_next;
 630                         (*scp)->sc_next = sc;
 631                         return 0;
 632                 }
 633         }
 634
 635         if ( append ) {
 636                 *scp = sc;
 637                 return 0;
 638         }
 639
 640         return 1;
 641 }
 642
 643 /*
 644  * default return code in case of missing backend function
 645  * and overlay stack returning SLAP_CB_CONTINUE
 646  */
 647 static int op_rc[ op_last ] = {
 648         LDAP_UNWILLING_TO_PERFORM,      /* bind */
 649         LDAP_UNWILLING_TO_PERFORM,      /* unbind */
 650         LDAP_UNWILLING_TO_PERFORM,      /* search */
 651         SLAP_CB_CONTINUE,               /* compare; pass to frontend */
 652         LDAP_UNWILLING_TO_PERFORM,      /* modify */
 653         LDAP_UNWILLING_TO_PERFORM,      /* modrdn */
 654         LDAP_UNWILLING_TO_PERFORM,      /* add */
 655         LDAP_UNWILLING_TO_PERFORM,      /* delete */
 656         LDAP_UNWILLING_TO_PERFORM,      /* abandon */
 657         LDAP_UNWILLING_TO_PERFORM,      /* cancel */
 658         LDAP_UNWILLING_TO_PERFORM,      /* extended */
 659         LDAP_SUCCESS,                   /* aux_operational */
 660         LDAP_SUCCESS,                   /* aux_chk_referrals */
 661         SLAP_CB_CONTINUE                /* aux_chk_controls; pass to frontend */
 662 };
 663
 664 int overlay_op_walk(
 665         Operation *op,
 666         SlapReply *rs,
 667         slap_operation_t which,
 668         slap_overinfo *oi,
 669         slap_overinst *on
 670 )
 671 {
 672         BackendInfo *bi;
 673         int rc = SLAP_CB_CONTINUE;
 674
 675         for (; on; on=on->on_next ) {
 676                 if ( on->on_bi.bi_flags & SLAPO_BFLAG_DISABLED )
 677                         continue;
 678                 bi = &on->on_bi;
 679                 if ( (&bi->bi_op_bind)[ which ] ) {
 680                         op->o_bd->bd_info = (BackendInfo *)on;
 681                         rc = (&bi->bi_op_bind)[ which ]( op, rs );
 682                         if ( rc != SLAP_CB_CONTINUE ) break;
 683                 }
 684         }
 685         if ( rc == SLAP_CB_BYPASS )
 686                 rc = SLAP_CB_CONTINUE;
 687         /* if an overlay halted processing, make sure
 688          * any previously set cleanup handlers are run
 689          */
 690         if ( rc != SLAP_CB_CONTINUE )
 691                 goto cleanup;
 692
 693         bi = oi->oi_orig;
 694         if ( (&bi->bi_op_bind)[ which ] ) {
 695                 op->o_bd->bd_info = bi;
 696                 rc = (&bi->bi_op_bind)[ which ]( op, rs );
 697         }
 698         /* should not fall thru this far without anything happening... */
 699         if ( rc == SLAP_CB_CONTINUE ) {
 700                 rc = op_rc[ which ];
 701         }
 702
 703         /* The underlying backend didn't handle the request, make sure
 704          * overlay cleanup is processed.
 705          */
 706         if ( rc == LDAP_UNWILLING_TO_PERFORM ) {
 707                 slap_callback *sc_next;
 708 cleanup:
 709                 for ( ; op->o_callback && op->o_callback->sc_response !=
 710                         over_back_response; op->o_callback = sc_next ) {
 711                         sc_next = op->o_callback->sc_next;
 712                         if ( op->o_callback->sc_cleanup ) {
 713                                 op->o_callback->sc_cleanup( op, rs );
 714                         }
 715                 }
 716         }
 717         return rc;
 718 }
 719
 720 static int
 721 over_op_func(
 722         Operation *op,
 723         SlapReply *rs,
 724         slap_operation_t which
 725 )
 726 {
 727         slap_overinfo *oi;
 728         slap_overinst *on;
 729         BackendDB *be = op->o_bd, db;
 730         slap_callback cb = {NULL, over_back_response, NULL, NULL}, **sc;
 731         int rc = SLAP_CB_CONTINUE;
 732
 733         /* FIXME: used to happen for instance during abandon
 734          * when global overlays are used... */
 735         assert( op->o_bd != NULL );
 736
 737         oi = op->o_bd->bd_info->bi_private;
 738         on = oi->oi_list;
 739
 740         if ( !SLAP_ISOVERLAY( op->o_bd )) {
 741                 db = *op->o_bd;
 742                 db.be_flags |= SLAP_DBFLAG_OVERLAY;
 743                 op->o_bd = &db;
 744         }
 745         cb.sc_next = op->o_callback;
 746         cb.sc_private = oi;
 747         op->o_callback = &cb;
 748
 749         rc = overlay_op_walk( op, rs, which, oi, on );
 750         for ( sc = &op->o_callback; *sc; sc = &(*sc)->sc_next ) {
 751                 if ( *sc == &cb ) {
 752                         *sc = cb.sc_next;
 753                         break;
 754                 }
 755         }
 756
 757         op->o_bd = be;
 758         return rc;
 759 }
 760
 761 static int
 762 over_op_bind( Operation *op, SlapReply *rs )
 763 {
 764         return over_op_func( op, rs, op_bind );
 765 }
 766
 767 static int
 768 over_op_unbind( Operation *op, SlapReply *rs )
 769 {
 770         return over_op_func( op, rs, op_unbind );
 771 }
 772
 773 static int
 774 over_op_search( Operation *op, SlapReply *rs )
 775 {
 776         return over_op_func( op, rs, op_search );
 777 }
 778
 779 static int
 780 over_op_compare( Operation *op, SlapReply *rs )
 781 {
 782         return over_op_func( op, rs, op_compare );
 783 }
 784
 785 static int
 786 over_op_modify( Operation *op, SlapReply *rs )
 787 {
 788         return over_op_func( op, rs, op_modify );
 789 }
 790
 791 static int
 792 over_op_modrdn( Operation *op, SlapReply *rs )
 793 {
 794         return over_op_func( op, rs, op_modrdn );
 795 }
 796
 797 static int
 798 over_op_add( Operation *op, SlapReply *rs )
 799 {
 800         return over_op_func( op, rs, op_add );
 801 }
 802
 803 static int
 804 over_op_delete( Operation *op, SlapReply *rs )
 805 {
 806         return over_op_func( op, rs, op_delete );
 807 }
 808
 809 static int
 810 over_op_abandon( Operation *op, SlapReply *rs )
 811 {
 812         return over_op_func( op, rs, op_abandon );
 813 }
 814
 815 static int
 816 over_op_cancel( Operation *op, SlapReply *rs )
 817 {
 818         return over_op_func( op, rs, op_cancel );
 819 }
 820
 821 static int
 822 over_op_extended( Operation *op, SlapReply *rs )
 823 {
 824         return over_op_func( op, rs, op_extended );
 825 }
 826
 827 static int
 828 over_aux_operational( Operation *op, SlapReply *rs )
 829 {
 830         return over_op_func( op, rs, op_aux_operational );
 831 }
 832
 833 static int
 834 over_aux_chk_referrals( Operation *op, SlapReply *rs )
 835 {
 836         return over_op_func( op, rs, op_aux_chk_referrals );
 837 }
 838
 839 static int
 840 over_aux_chk_controls( Operation *op, SlapReply *rs )
 841 {
 842         return over_op_func( op, rs, op_aux_chk_controls );
 843 }
 844
 845 enum conn_which {
 846         conn_init = 0,
 847         conn_destroy,
 848         conn_last
 849 };
 850
 851 static int
 852 over_connection_func(
 853         BackendDB       *bd,
 854         Connection      *conn,
 855         enum conn_which which
 856 )
 857 {
 858         slap_overinfo           *oi;
 859         slap_overinst           *on;
 860         BackendDB               db;
 861         int                     rc = SLAP_CB_CONTINUE;
 862         BI_connection_init      **func;
 863
 864         /* FIXME: used to happen for instance during abandon
 865          * when global overlays are used... */
 866         assert( bd != NULL );
 867
 868         oi = bd->bd_info->bi_private;
 869         on = oi->oi_list;
 870
 871         if ( !SLAP_ISOVERLAY( bd ) ) {
 872                 db = *bd;
 873                 db.be_flags |= SLAP_DBFLAG_OVERLAY;
 874                 bd = &db;
 875         }
 876
 877         for ( ; on; on = on->on_next ) {
 878                 if ( on->on_bi.bi_flags & SLAPO_BFLAG_DISABLED )
 879                         continue;
 880                 func = &on->on_bi.bi_connection_init;
 881                 if ( func[ which ] ) {
 882                         bd->bd_info = (BackendInfo *)on;
 883                         rc = func[ which ]( bd, conn );
 884                         if ( rc != SLAP_CB_CONTINUE ) break;
 885                 }
 886         }
 887
 888         func = &oi->oi_orig->bi_connection_init;
 889         if ( func[ which ] && rc == SLAP_CB_CONTINUE ) {
 890                 bd->bd_info = oi->oi_orig;
 891                 rc = func[ which ]( bd, conn );
 892         }
 893         /* should not fall thru this far without anything happening... */
 894         if ( rc == SLAP_CB_CONTINUE ) {
 895                 rc = LDAP_UNWILLING_TO_PERFORM;
 896         }
 897
 898         return rc;
 899 }
 900
 901 static int
 902 over_connection_init(
 903         BackendDB       *bd,
 904         Connection      *conn
 905 )
 906 {
 907         return over_connection_func( bd, conn, conn_init );
 908 }
 909
 910 static int
 911 over_connection_destroy(
 912         BackendDB       *bd,
 913         Connection      *conn
 914 )
 915 {
 916         return over_connection_func( bd, conn, conn_destroy );
 917 }
 918
 919 int
 920 overlay_register(
 921         slap_overinst *on
 922 )
 923 {
 924         slap_overinst   *tmp;
 925
 926         /* FIXME: check for duplicates? */
 927         for ( tmp = overlays; tmp != NULL; tmp = tmp->on_next ) {
 928                 if ( strcmp( on->on_bi.bi_type, tmp->on_bi.bi_type ) == 0 ) {
 929                         Debug( LDAP_DEBUG_ANY,
 930                                 "overlay_register(\"%s\"): "
 931                                 "name already in use.\n",
 932                                 on->on_bi.bi_type, 0, 0 );
 933                         return -1;
 934                 }
 935
 936                 if ( on->on_bi.bi_obsolete_names != NULL ) {
 937                         int     i;
 938
 939                         for ( i = 0; on->on_bi.bi_obsolete_names[ i ] != NULL; i++ ) {
 940                                 if ( strcmp( on->on_bi.bi_obsolete_names[ i ], tmp->on_bi.bi_type ) == 0 ) {
 941                                         Debug( LDAP_DEBUG_ANY,
 942                                                 "overlay_register(\"%s\"): "
 943                                                 "obsolete name \"%s\" already in use "
 944                                                 "by overlay \"%s\".\n",
 945                                                 on->on_bi.bi_type,
 946                                                 on->on_bi.bi_obsolete_names[ i ],
 947                                                 tmp->on_bi.bi_type );
 948                                         return -1;
 949                                 }
 950                         }
 951                 }
 952
 953                 if ( tmp->on_bi.bi_obsolete_names != NULL ) {
 954                         int     i;
 955
 956                         for ( i = 0; tmp->on_bi.bi_obsolete_names[ i ] != NULL; i++ ) {
 957                                 int     j;
 958
 959                                 if ( strcmp( on->on_bi.bi_type, tmp->on_bi.bi_obsolete_names[ i ] ) == 0 ) {
 960                                         Debug( LDAP_DEBUG_ANY,
 961                                                 "overlay_register(\"%s\"): "
 962                                                 "name already in use "
 963                                                 "as obsolete by overlay \"%s\".\n",
 964                                                 on->on_bi.bi_type,
 965                                                 tmp->on_bi.bi_obsolete_names[ i ], 0 );
 966                                         return -1;
 967                                 }
 968
 969                                 if ( on->on_bi.bi_obsolete_names != NULL ) {
 970                                         for ( j = 0; on->on_bi.bi_obsolete_names[ j ] != NULL; j++ ) {
 971                                                 if ( strcmp( on->on_bi.bi_obsolete_names[ j ], tmp->on_bi.bi_obsolete_names[ i ] ) == 0 ) {
 972                                                         Debug( LDAP_DEBUG_ANY,
 973                                                                 "overlay_register(\"%s\"): "
 974                                                                 "obsolete name \"%s\" already in use "
 975                                                                 "as obsolete by overlay \"%s\".\n",
 976                                                                 on->on_bi.bi_type,
 977                                                                 on->on_bi.bi_obsolete_names[ j ],
 978                                                                 tmp->on_bi.bi_type );
 979                                                         return -1;
 980                                                 }
 981                                         }
 982                                 }
 983                         }
 984                 }
 985         }
 986
 987         on->on_next = overlays;
 988         overlays = on;
 989         return 0;
 990 }
 991
 992 /*
 993  * iterator on registered overlays; overlay_next( NULL ) returns the first
 994  * overlay; subsequent calls with the previously returned value allow to
 995  * iterate over the entire list; returns NULL when no more overlays are
 996  * registered.
 997  */
 998
 999 slap_overinst *
1000 overlay_next(
1001         slap_overinst *on
1002 )
1003 {
1004         if ( on == NULL ) {
1005                 return overlays;
1006         }
1007
1008         return on->on_next;
1009 }
1010
1011 /*
1012  * returns a specific registered overlay based on the type; NULL if not
1013  * registered.
1014  */
1015
1016 slap_overinst *
1017 overlay_find( const char *over_type )
1018 {
1019         slap_overinst *on = overlays;
1020
1021         assert( over_type != NULL );
1022
1023         for ( ; on; on = on->on_next ) {
1024                 if ( strcmp( on->on_bi.bi_type, over_type ) == 0 ) {
1025                         goto foundit;
1026                 }
1027
1028                 if ( on->on_bi.bi_obsolete_names != NULL ) {
1029                         int     i;
1030
1031                         for ( i = 0; on->on_bi.bi_obsolete_names[ i ] != NULL; i++ ) {
1032                                 if ( strcmp( on->on_bi.bi_obsolete_names[ i ], over_type ) == 0 ) {
1033                                         Debug( LDAP_DEBUG_ANY,
1034                                                 "overlay_find(\"%s\"): "
1035                                                 "obsolete name for \"%s\".\n",
1036                                                 on->on_bi.bi_obsolete_names[ i ],
1037                                                 on->on_bi.bi_type, 0 );
1038                                         goto foundit;
1039                                 }
1040                         }
1041                 }
1042         }
1043
1044 foundit:;
1045         return on;
1046 }
1047
1048 static const char overtype[] = "over";
1049
1050 /*
1051  * returns TRUE (1) if the database is actually an overlay instance;
1052  * FALSE (0) otherwise.
1053  */
1054
1055 int
1056 overlay_is_over( BackendDB *be )
1057 {
1058         return be->bd_info->bi_type == overtype;
1059 }
1060
1061 /*
1062  * returns TRUE (1) if the given database is actually an overlay
1063  * instance and, somewhere in the list, contains the requested overlay;
1064  * FALSE (0) otherwise.
1065  */
1066
1067 int
1068 overlay_is_inst( BackendDB *be, const char *over_type )
1069 {
1070         slap_overinst   *on;
1071
1072         assert( be != NULL );
1073
1074         if ( !overlay_is_over( be ) ) {
1075                 return 0;
1076         }
1077
1078         on = ((slap_overinfo *)be->bd_info->bi_private)->oi_list;
1079         for ( ; on; on = on->on_next ) {
1080                 if ( strcmp( on->on_bi.bi_type, over_type ) == 0 ) {
1081                         return 1;
1082                 }
1083         }
1084
1085         return 0;
1086 }
1087
1088 int
1089 overlay_register_control( BackendDB *be, const char *oid )
1090 {
1091         int             gotit = 0;
1092         int             cid;
1093
1094         if ( slap_find_control_id( oid, &cid ) == LDAP_CONTROL_NOT_FOUND ) {
1095                 return -1;
1096         }
1097
1098         if ( SLAP_ISGLOBALOVERLAY( be ) ) {
1099                 BackendDB *bd;
1100
1101                 /* add to all backends... */
1102                 LDAP_STAILQ_FOREACH( bd, &backendDB, be_next ) {
1103                         if ( bd == be->bd_self ) {
1104                                 gotit = 1;
1105                         }
1106
1107                         /* overlays can be instanciated multiple times, use
1108                          * be_ctrls[ cid ] as an instance counter, so that the
1109                          * overlay's controls are only really disabled after the
1110                          * last instance called overlay_register_control() */
1111                         bd->be_ctrls[ cid ]++;
1112                         bd->be_ctrls[ SLAP_MAX_CIDS ] = 1;
1113                 }
1114
1115         }
1116
1117         if ( !gotit ) {
1118                 /* overlays can be instanciated multiple times, use
1119                  * be_ctrls[ cid ] as an instance counter, so that the
1120                  * overlay's controls are only really unregistered after the
1121                  * last instance called overlay_register_control() */
1122                 be->bd_self->be_ctrls[ cid ]++;
1123                 be->bd_self->be_ctrls[ SLAP_MAX_CIDS ] = 1;
1124         }
1125
1126         return 0;
1127 }
1128
1129 #ifdef SLAP_CONFIG_DELETE
1130 void
1131 overlay_unregister_control( BackendDB *be, const char *oid )
1132 {
1133         int             gotit = 0;
1134         int             cid;
1135
1136         if ( slap_find_control_id( oid, &cid ) == LDAP_CONTROL_NOT_FOUND ) {
1137                 return;
1138         }
1139
1140         if ( SLAP_ISGLOBALOVERLAY( be ) ) {
1141                 BackendDB *bd;
1142
1143                 /* remove from all backends... */
1144                 LDAP_STAILQ_FOREACH( bd, &backendDB, be_next ) {
1145                         if ( bd == be->bd_self ) {
1146                                 gotit = 1;
1147                         }
1148
1149                         bd->be_ctrls[ cid ]--;
1150                 }
1151         }
1152
1153         if ( !gotit ) {
1154                 be->bd_self->be_ctrls[ cid ]--;
1155         }
1156 }
1157 #endif /* SLAP_CONFIG_DELETE */
1158
1159 void
1160 overlay_destroy_one( BackendDB *be, slap_overinst *on )
1161 {
1162         slap_overinfo *oi = on->on_info;
1163         slap_overinst **oidx;
1164
1165         for ( oidx = &oi->oi_list; *oidx; oidx = &(*oidx)->on_next ) {
1166                 if ( *oidx == on ) {
1167                         *oidx = on->on_next;
1168                         if ( on->on_bi.bi_db_destroy ) {
1169                                 BackendInfo *bi_orig = be->bd_info;
1170                                 be->bd_info = (BackendInfo *)on;
1171                                 on->on_bi.bi_db_destroy( be, NULL );
1172                                 be->bd_info = bi_orig;
1173                         }
1174                         free( on );
1175                         break;
1176                 }
1177         }
1178 }
1179
1180 #ifdef SLAP_CONFIG_DELETE
1181 typedef struct ov_remove_ctx {
1182         BackendDB *be;
1183         slap_overinst *on;
1184 } ov_remove_ctx;
1185
1186 int
1187 overlay_remove_cb( Operation *op, SlapReply *rs )
1188 {
1189         ov_remove_ctx *rm_ctx = (ov_remove_ctx*) op->o_callback->sc_private;
1190         BackendInfo *bi_orig = rm_ctx->be->bd_info;
1191
1192         rm_ctx->be->bd_info = (BackendInfo*) rm_ctx->on;
1193
1194         if ( rm_ctx->on->on_bi.bi_db_close ) {
1195                 rm_ctx->on->on_bi.bi_db_close( rm_ctx->be, NULL );
1196         }
1197         if ( rm_ctx->on->on_bi.bi_db_destroy ) {
1198                 rm_ctx->on->on_bi.bi_db_destroy( rm_ctx->be, NULL );
1199         }
1200
1201         /* clean up after removing last overlay */
1202         if ( ! rm_ctx->on->on_info->oi_list ) {
1203                 /* reset db flags and bd_info to orig */
1204                 SLAP_DBFLAGS( rm_ctx->be ) &= ~SLAP_DBFLAG_GLOBAL_OVERLAY;
1205                 rm_ctx->be->bd_info = rm_ctx->on->on_info->oi_orig;
1206                 ch_free(rm_ctx->on->on_info);
1207         } else {
1208                 rm_ctx->be->bd_info = bi_orig;
1209         }
1210         free( rm_ctx->on );
1211         op->o_tmpfree(rm_ctx, op->o_tmpmemctx);
1212         return SLAP_CB_CONTINUE;
1213 }
1214
1215 void
1216 overlay_remove( BackendDB *be, slap_overinst *on, Operation *op )
1217 {
1218         slap_overinfo *oi = on->on_info;
1219         slap_overinst **oidx;
1220         ov_remove_ctx *rm_ctx;
1221         slap_callback *rm_cb, *cb;
1222
1223         /* remove overlay from oi_list */
1224         for ( oidx = &oi->oi_list; *oidx; oidx = &(*oidx)->on_next ) {
1225                 if ( *oidx == on ) {
1226                         *oidx = on->on_next;
1227                         break;
1228                 }
1229         }
1230
1231         /* The db_close and db_destroy handlers to cleanup a release
1232          * the overlay's resources are called from the cleanup callback
1233          */
1234         rm_ctx = op->o_tmpalloc( sizeof( ov_remove_ctx ), op->o_tmpmemctx );
1235         rm_ctx->be = be;
1236         rm_ctx->on = on;
1237
1238         rm_cb = op->o_tmpalloc( sizeof( slap_callback ), op->o_tmpmemctx );
1239         rm_cb->sc_next = NULL;
1240         rm_cb->sc_cleanup = overlay_remove_cb;
1241         rm_cb->sc_response = NULL;
1242         rm_cb->sc_private = (void*) rm_ctx;
1243
1244         /* Append callback to the end of the list */
1245         if ( !op->o_callback ) {
1246                 op->o_callback = rm_cb;
1247         } else {
1248                 for ( cb = op->o_callback; cb->sc_next; cb = cb->sc_next );
1249                 cb->sc_next = rm_cb;
1250         }
1251 }
1252 #endif /* SLAP_CONFIG_DELETE */
1253
1254 void
1255 overlay_insert( BackendDB *be, slap_overinst *on2, slap_overinst ***prev,
1256         int idx )
1257 {
1258         slap_overinfo *oi = (slap_overinfo *)be->bd_info;
1259
1260         if ( idx == -1 ) {
1261                 on2->on_next = oi->oi_list;
1262                 oi->oi_list = on2;
1263         } else {
1264                 int i, novs;
1265                 slap_overinst *on, **prev;
1266
1267                 /* Since the list is in reverse order and is singly linked,
1268                  * we have to count the overlays and then insert backwards.
1269                  * Adding on overlay at a specific point should be a pretty
1270                  * infrequent occurrence.
1271                  */
1272                 novs = 0;
1273                 for ( on = oi->oi_list; on; on=on->on_next )
1274                         novs++;
1275
1276                 if (idx > novs)
1277                         idx = 0;
1278                 else
1279                         idx = novs - idx;
1280
1281                 /* advance to insertion point */
1282                 prev = &oi->oi_list;
1283                 for ( i=0; i<idx; i++ ) {
1284                         on = *prev;
1285                         prev = &on->on_next;
1286                 }
1287                 /* insert */
1288                 on2->on_next = *prev;
1289                 *prev = on2;
1290         }
1291 }
1292
1293 void
1294 overlay_move( BackendDB *be, slap_overinst *on, int idx )
1295 {
1296         slap_overinfo *oi = (slap_overinfo *)be->bd_info;
1297         slap_overinst **onp;
1298
1299         for (onp = &oi->oi_list; *onp; onp= &(*onp)->on_next) {
1300                 if ( *onp == on ) {
1301                         *onp = on->on_next;
1302                         break;
1303                 }
1304         }
1305         overlay_insert( be, on, &onp, idx );
1306 }
1307
1308 /* add an overlay to a particular backend. */
1309 int
1310 overlay_config( BackendDB *be, const char *ov, int idx, BackendInfo **res, ConfigReply *cr )
1311 {
1312         slap_overinst *on = NULL, *on2 = NULL, **prev;
1313         slap_overinfo *oi = NULL;
1314         BackendInfo *bi = NULL;
1315
1316         if ( res )
1317                 *res = NULL;
1318
1319         on = overlay_find( ov );
1320         if ( !on ) {
1321                 Debug( LDAP_DEBUG_ANY, "overlay \"%s\" not found\n", ov, 0, 0 );
1322                 return 1;
1323         }
1324
1325         /* If this is the first overlay on this backend, set up the
1326          * overlay info structure
1327          */
1328         if ( !overlay_is_over( be ) ) {
1329                 int     isglobal = 0;
1330
1331                 /* NOTE: the first time a global overlay is configured,
1332                  * frontendDB gets this flag; it is used later by overlays
1333                  * to determine if they're stacked on top of the frontendDB */
1334                 if ( be->bd_info == frontendDB->bd_info || SLAP_ISGLOBALOVERLAY( be ) ) {
1335                         isglobal = 1;
1336                         if ( on->on_bi.bi_flags & SLAPO_BFLAG_DBONLY ) {
1337                                 Debug( LDAP_DEBUG_ANY, "overlay_config(): "
1338                                         "overlay \"%s\" cannot be global.\n",
1339                                         ov, 0, 0 );
1340                                 return 1;
1341                         }
1342
1343                 } else if ( on->on_bi.bi_flags & SLAPO_BFLAG_GLOBONLY ) {
1344                         Debug( LDAP_DEBUG_ANY, "overlay_config(): "
1345                                 "overlay \"%s\" can only be global.\n",
1346                                 ov, 0, 0 );
1347                         return 1;
1348                 }
1349
1350                 oi = ch_malloc( sizeof( slap_overinfo ) );
1351                 oi->oi_orig = be->bd_info;
1352                 oi->oi_bi = *be->bd_info;
1353                 oi->oi_origdb = be;
1354
1355                 if ( isglobal ) {
1356                         SLAP_DBFLAGS( be ) |= SLAP_DBFLAG_GLOBAL_OVERLAY;
1357                 }
1358
1359                 /* Save a pointer to ourself in bi_private.
1360                  */
1361                 oi->oi_bi.bi_private = oi;
1362                 oi->oi_list = NULL;
1363                 bi = (BackendInfo *)oi;
1364
1365                 bi->bi_type = (char *)overtype;
1366
1367                 bi->bi_db_config = over_db_config;
1368                 bi->bi_db_open = over_db_open;
1369                 bi->bi_db_close = over_db_close;
1370                 bi->bi_db_destroy = over_db_destroy;
1371
1372                 bi->bi_op_bind = over_op_bind;
1373                 bi->bi_op_unbind = over_op_unbind;
1374                 bi->bi_op_search = over_op_search;
1375                 bi->bi_op_compare = over_op_compare;
1376                 bi->bi_op_modify = over_op_modify;
1377                 bi->bi_op_modrdn = over_op_modrdn;
1378                 bi->bi_op_add = over_op_add;
1379                 bi->bi_op_delete = over_op_delete;
1380                 bi->bi_op_abandon = over_op_abandon;
1381                 bi->bi_op_cancel = over_op_cancel;
1382
1383                 bi->bi_extended = over_op_extended;
1384
1385                 /*
1386                  * this is fine because it has the same
1387                  * args of the operations; we need to rework
1388                  * all the hooks to share the same args
1389                  * of the operations...
1390                  */
1391                 bi->bi_operational = over_aux_operational;
1392                 bi->bi_chk_referrals = over_aux_chk_referrals;
1393                 bi->bi_chk_controls = over_aux_chk_controls;
1394
1395                 /* these have specific arglists */
1396                 bi->bi_entry_get_rw = over_entry_get_rw;
1397                 bi->bi_entry_release_rw = over_entry_release_rw;
1398                 bi->bi_access_allowed = over_access_allowed;
1399                 bi->bi_acl_group = over_acl_group;
1400                 bi->bi_acl_attribute = over_acl_attribute;
1401
1402                 bi->bi_connection_init = over_connection_init;
1403                 bi->bi_connection_destroy = over_connection_destroy;
1404
1405                 be->bd_info = bi;
1406
1407         } else {
1408                 if ( overlay_is_inst( be, ov ) ) {
1409                         if ( SLAPO_SINGLE( be ) ) {
1410                                 Debug( LDAP_DEBUG_ANY, "overlay_config(): "
1411                                         "overlay \"%s\" already in list\n",
1412                                         ov, 0, 0 );
1413                                 return 1;
1414                         }
1415                 }
1416
1417                 oi = be->bd_info->bi_private;
1418         }
1419
1420         /* Insert new overlay into list. By default overlays are
1421          * added to head of list and executed in LIFO order.
1422          */
1423         on2 = ch_calloc( 1, sizeof(slap_overinst) );
1424         *on2 = *on;
1425         on2->on_info = oi;
1426
1427         prev = &oi->oi_list;
1428         /* Do we need to find the insertion point? */
1429         if ( idx >= 0 ) {
1430                 int i;
1431
1432                 /* count current overlays */
1433                 for ( i=0, on=oi->oi_list; on; on=on->on_next, i++ );
1434
1435                 /* are we just appending a new one? */
1436                 if ( idx >= i )
1437                         idx = -1;
1438         }
1439         overlay_insert( be, on2, &prev, idx );
1440
1441         /* Any initialization needed? */
1442         if ( on2->on_bi.bi_db_init ) {
1443                 int rc;
1444                 be->bd_info = (BackendInfo *)on2;
1445                 rc = on2->on_bi.bi_db_init( be, cr);
1446                 be->bd_info = (BackendInfo *)oi;
1447                 if ( rc ) {
1448                         *prev = on2->on_next;
1449                         ch_free( on2 );
1450                         on2 = NULL;
1451                         return rc;
1452                 }
1453         }
1454
1455         if ( res )
1456                 *res = &on2->on_bi;
1457
1458         return 0;
1459 }