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 2003-2014 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
 688         bi = oi->oi_orig;
 689         if ( (&bi->bi_op_bind)[ which ] && rc == SLAP_CB_CONTINUE ) {
 690                 op->o_bd->bd_info = bi;
 691                 rc = (&bi->bi_op_bind)[ which ]( op, rs );
 692         }
 693         /* should not fall thru this far without anything happening... */
 694         if ( rc == SLAP_CB_CONTINUE ) {
 695                 rc = op_rc[ which ];
 696         }
 697
 698         /* The underlying backend didn't handle the request, make sure
 699          * overlay cleanup is processed.
 700          */
 701         if ( rc == LDAP_UNWILLING_TO_PERFORM ) {
 702                 slap_callback *sc_next;
 703                 for ( ; op->o_callback && op->o_callback->sc_response !=
 704                         over_back_response; op->o_callback = sc_next ) {
 705                         sc_next = op->o_callback->sc_next;
 706                         if ( op->o_callback->sc_cleanup ) {
 707                                 op->o_callback->sc_cleanup( op, rs );
 708                         }
 709                 }
 710         }
 711         return rc;
 712 }
 713
 714 static int
 715 over_op_func(
 716         Operation *op,
 717         SlapReply *rs,
 718         slap_operation_t which
 719 )
 720 {
 721         slap_overinfo *oi;
 722         slap_overinst *on;
 723         BackendDB *be = op->o_bd, db;
 724         slap_callback cb = {NULL, over_back_response, NULL, NULL}, **sc;
 725         int rc = SLAP_CB_CONTINUE;
 726
 727         /* FIXME: used to happen for instance during abandon
 728          * when global overlays are used... */
 729         assert( op->o_bd != NULL );
 730
 731         oi = op->o_bd->bd_info->bi_private;
 732         on = oi->oi_list;
 733
 734         if ( !SLAP_ISOVERLAY( op->o_bd )) {
 735                 db = *op->o_bd;
 736                 db.be_flags |= SLAP_DBFLAG_OVERLAY;
 737                 op->o_bd = &db;
 738         }
 739         cb.sc_next = op->o_callback;
 740         cb.sc_private = oi;
 741         op->o_callback = &cb;
 742
 743         rc = overlay_op_walk( op, rs, which, oi, on );
 744         for ( sc = &op->o_callback; *sc; sc = &(*sc)->sc_next ) {
 745                 if ( *sc == &cb ) {
 746                         *sc = cb.sc_next;
 747                         break;
 748                 }
 749         }
 750
 751         op->o_bd = be;
 752         return rc;
 753 }
 754
 755 static int
 756 over_op_bind( Operation *op, SlapReply *rs )
 757 {
 758         return over_op_func( op, rs, op_bind );
 759 }
 760
 761 static int
 762 over_op_unbind( Operation *op, SlapReply *rs )
 763 {
 764         return over_op_func( op, rs, op_unbind );
 765 }
 766
 767 static int
 768 over_op_search( Operation *op, SlapReply *rs )
 769 {
 770         return over_op_func( op, rs, op_search );
 771 }
 772
 773 static int
 774 over_op_compare( Operation *op, SlapReply *rs )
 775 {
 776         return over_op_func( op, rs, op_compare );
 777 }
 778
 779 static int
 780 over_op_modify( Operation *op, SlapReply *rs )
 781 {
 782         return over_op_func( op, rs, op_modify );
 783 }
 784
 785 static int
 786 over_op_modrdn( Operation *op, SlapReply *rs )
 787 {
 788         return over_op_func( op, rs, op_modrdn );
 789 }
 790
 791 static int
 792 over_op_add( Operation *op, SlapReply *rs )
 793 {
 794         return over_op_func( op, rs, op_add );
 795 }
 796
 797 static int
 798 over_op_delete( Operation *op, SlapReply *rs )
 799 {
 800         return over_op_func( op, rs, op_delete );
 801 }
 802
 803 static int
 804 over_op_abandon( Operation *op, SlapReply *rs )
 805 {
 806         return over_op_func( op, rs, op_abandon );
 807 }
 808
 809 static int
 810 over_op_cancel( Operation *op, SlapReply *rs )
 811 {
 812         return over_op_func( op, rs, op_cancel );
 813 }
 814
 815 static int
 816 over_op_extended( Operation *op, SlapReply *rs )
 817 {
 818         return over_op_func( op, rs, op_extended );
 819 }
 820
 821 static int
 822 over_aux_operational( Operation *op, SlapReply *rs )
 823 {
 824         return over_op_func( op, rs, op_aux_operational );
 825 }
 826
 827 static int
 828 over_aux_chk_referrals( Operation *op, SlapReply *rs )
 829 {
 830         return over_op_func( op, rs, op_aux_chk_referrals );
 831 }
 832
 833 static int
 834 over_aux_chk_controls( Operation *op, SlapReply *rs )
 835 {
 836         return over_op_func( op, rs, op_aux_chk_controls );
 837 }
 838
 839 enum conn_which {
 840         conn_init = 0,
 841         conn_destroy,
 842         conn_last
 843 };
 844
 845 static int
 846 over_connection_func(
 847         BackendDB       *bd,
 848         Connection      *conn,
 849         enum conn_which which
 850 )
 851 {
 852         slap_overinfo           *oi;
 853         slap_overinst           *on;
 854         BackendDB               db;
 855         int                     rc = SLAP_CB_CONTINUE;
 856         BI_connection_init      **func;
 857
 858         /* FIXME: used to happen for instance during abandon
 859          * when global overlays are used... */
 860         assert( bd != NULL );
 861
 862         oi = bd->bd_info->bi_private;
 863         on = oi->oi_list;
 864
 865         if ( !SLAP_ISOVERLAY( bd ) ) {
 866                 db = *bd;
 867                 db.be_flags |= SLAP_DBFLAG_OVERLAY;
 868                 bd = &db;
 869         }
 870
 871         for ( ; on; on = on->on_next ) {
 872                 if ( on->on_bi.bi_flags & SLAPO_BFLAG_DISABLED )
 873                         continue;
 874                 func = &on->on_bi.bi_connection_init;
 875                 if ( func[ which ] ) {
 876                         bd->bd_info = (BackendInfo *)on;
 877                         rc = func[ which ]( bd, conn );
 878                         if ( rc != SLAP_CB_CONTINUE ) break;
 879                 }
 880         }
 881
 882         func = &oi->oi_orig->bi_connection_init;
 883         if ( func[ which ] && rc == SLAP_CB_CONTINUE ) {
 884                 bd->bd_info = oi->oi_orig;
 885                 rc = func[ which ]( bd, conn );
 886         }
 887         /* should not fall thru this far without anything happening... */
 888         if ( rc == SLAP_CB_CONTINUE ) {
 889                 rc = LDAP_UNWILLING_TO_PERFORM;
 890         }
 891
 892         return rc;
 893 }
 894
 895 static int
 896 over_connection_init(
 897         BackendDB       *bd,
 898         Connection      *conn
 899 )
 900 {
 901         return over_connection_func( bd, conn, conn_init );
 902 }
 903
 904 static int
 905 over_connection_destroy(
 906         BackendDB       *bd,
 907         Connection      *conn
 908 )
 909 {
 910         return over_connection_func( bd, conn, conn_destroy );
 911 }
 912
 913 int
 914 overlay_register(
 915         slap_overinst *on
 916 )
 917 {
 918         slap_overinst   *tmp;
 919
 920         /* FIXME: check for duplicates? */
 921         for ( tmp = overlays; tmp != NULL; tmp = tmp->on_next ) {
 922                 if ( strcmp( on->on_bi.bi_type, tmp->on_bi.bi_type ) == 0 ) {
 923                         Debug( LDAP_DEBUG_ANY,
 924                                 "overlay_register(\"%s\"): "
 925                                 "name already in use.\n",
 926                                 on->on_bi.bi_type, 0, 0 );
 927                         return -1;
 928                 }
 929
 930                 if ( on->on_bi.bi_obsolete_names != NULL ) {
 931                         int     i;
 932
 933                         for ( i = 0; on->on_bi.bi_obsolete_names[ i ] != NULL; i++ ) {
 934                                 if ( strcmp( on->on_bi.bi_obsolete_names[ i ], tmp->on_bi.bi_type ) == 0 ) {
 935                                         Debug( LDAP_DEBUG_ANY,
 936                                                 "overlay_register(\"%s\"): "
 937                                                 "obsolete name \"%s\" already in use "
 938                                                 "by overlay \"%s\".\n",
 939                                                 on->on_bi.bi_type,
 940                                                 on->on_bi.bi_obsolete_names[ i ],
 941                                                 tmp->on_bi.bi_type );
 942                                         return -1;
 943                                 }
 944                         }
 945                 }
 946
 947                 if ( tmp->on_bi.bi_obsolete_names != NULL ) {
 948                         int     i;
 949
 950                         for ( i = 0; tmp->on_bi.bi_obsolete_names[ i ] != NULL; i++ ) {
 951                                 int     j;
 952
 953                                 if ( strcmp( on->on_bi.bi_type, tmp->on_bi.bi_obsolete_names[ i ] ) == 0 ) {
 954                                         Debug( LDAP_DEBUG_ANY,
 955                                                 "overlay_register(\"%s\"): "
 956                                                 "name already in use "
 957                                                 "as obsolete by overlay \"%s\".\n",
 958                                                 on->on_bi.bi_type,
 959                                                 tmp->on_bi.bi_obsolete_names[ i ], 0 );
 960                                         return -1;
 961                                 }
 962
 963                                 if ( on->on_bi.bi_obsolete_names != NULL ) {
 964                                         for ( j = 0; on->on_bi.bi_obsolete_names[ j ] != NULL; j++ ) {
 965                                                 if ( strcmp( on->on_bi.bi_obsolete_names[ j ], tmp->on_bi.bi_obsolete_names[ i ] ) == 0 ) {
 966                                                         Debug( LDAP_DEBUG_ANY,
 967                                                                 "overlay_register(\"%s\"): "
 968                                                                 "obsolete name \"%s\" already in use "
 969                                                                 "as obsolete by overlay \"%s\".\n",
 970                                                                 on->on_bi.bi_type,
 971                                                                 on->on_bi.bi_obsolete_names[ j ],
 972                                                                 tmp->on_bi.bi_type );
 973                                                         return -1;
 974                                                 }
 975                                         }
 976                                 }
 977                         }
 978                 }
 979         }
 980
 981         on->on_next = overlays;
 982         overlays = on;
 983         return 0;
 984 }
 985
 986 /*
 987  * iterator on registered overlays; overlay_next( NULL ) returns the first
 988  * overlay; subsequent calls with the previously returned value allow to
 989  * iterate over the entire list; returns NULL when no more overlays are
 990  * registered.
 991  */
 992
 993 slap_overinst *
 994 overlay_next(
 995         slap_overinst *on
 996 )
 997 {
 998         if ( on == NULL ) {
 999                 return overlays;
1000         }
1001
1002         return on->on_next;
1003 }
1004
1005 /*
1006  * returns a specific registered overlay based on the type; NULL if not
1007  * registered.
1008  */
1009
1010 slap_overinst *
1011 overlay_find( const char *over_type )
1012 {
1013         slap_overinst *on = overlays;
1014
1015         assert( over_type != NULL );
1016
1017         for ( ; on; on = on->on_next ) {
1018                 if ( strcmp( on->on_bi.bi_type, over_type ) == 0 ) {
1019                         goto foundit;
1020                 }
1021
1022                 if ( on->on_bi.bi_obsolete_names != NULL ) {
1023                         int     i;
1024
1025                         for ( i = 0; on->on_bi.bi_obsolete_names[ i ] != NULL; i++ ) {
1026                                 if ( strcmp( on->on_bi.bi_obsolete_names[ i ], over_type ) == 0 ) {
1027                                         Debug( LDAP_DEBUG_ANY,
1028                                                 "overlay_find(\"%s\"): "
1029                                                 "obsolete name for \"%s\".\n",
1030                                                 on->on_bi.bi_obsolete_names[ i ],
1031                                                 on->on_bi.bi_type, 0 );
1032                                         goto foundit;
1033                                 }
1034                         }
1035                 }
1036         }
1037
1038 foundit:;
1039         return on;
1040 }
1041
1042 static const char overtype[] = "over";
1043
1044 /*
1045  * returns TRUE (1) if the database is actually an overlay instance;
1046  * FALSE (0) otherwise.
1047  */
1048
1049 int
1050 overlay_is_over( BackendDB *be )
1051 {
1052         return be->bd_info->bi_type == overtype;
1053 }
1054
1055 /*
1056  * returns TRUE (1) if the given database is actually an overlay
1057  * instance and, somewhere in the list, contains the requested overlay;
1058  * FALSE (0) otherwise.
1059  */
1060
1061 int
1062 overlay_is_inst( BackendDB *be, const char *over_type )
1063 {
1064         slap_overinst   *on;
1065
1066         assert( be != NULL );
1067
1068         if ( !overlay_is_over( be ) ) {
1069                 return 0;
1070         }
1071
1072         on = ((slap_overinfo *)be->bd_info->bi_private)->oi_list;
1073         for ( ; on; on = on->on_next ) {
1074                 if ( strcmp( on->on_bi.bi_type, over_type ) == 0 ) {
1075                         return 1;
1076                 }
1077         }
1078
1079         return 0;
1080 }
1081
1082 int
1083 overlay_register_control( BackendDB *be, const char *oid )
1084 {
1085         int             gotit = 0;
1086         int             cid;
1087
1088         if ( slap_find_control_id( oid, &cid ) == LDAP_CONTROL_NOT_FOUND ) {
1089                 return -1;
1090         }
1091
1092         if ( SLAP_ISGLOBALOVERLAY( be ) ) {
1093                 BackendDB *bd;
1094
1095                 /* add to all backends... */
1096                 LDAP_STAILQ_FOREACH( bd, &backendDB, be_next ) {
1097                         if ( bd == be->bd_self ) {
1098                                 gotit = 1;
1099                         }
1100
1101                         /* overlays can be instanciated multiple times, use
1102                          * be_ctrls[ cid ] as an instance counter, so that the
1103                          * overlay's controls are only really disabled after the
1104                          * last instance called overlay_register_control() */
1105                         bd->be_ctrls[ cid ]++;
1106                         bd->be_ctrls[ SLAP_MAX_CIDS ] = 1;
1107                 }
1108
1109         }
1110
1111         if ( !gotit ) {
1112                 /* overlays can be instanciated multiple times, use
1113                  * be_ctrls[ cid ] as an instance counter, so that the
1114                  * overlay's controls are only really unregistered after the
1115                  * last instance called overlay_register_control() */
1116                 be->bd_self->be_ctrls[ cid ]++;
1117                 be->bd_self->be_ctrls[ SLAP_MAX_CIDS ] = 1;
1118         }
1119
1120         return 0;
1121 }
1122
1123 #ifdef SLAP_CONFIG_DELETE
1124 void
1125 overlay_unregister_control( BackendDB *be, const char *oid )
1126 {
1127         int             gotit = 0;
1128         int             cid;
1129
1130         if ( slap_find_control_id( oid, &cid ) == LDAP_CONTROL_NOT_FOUND ) {
1131                 return;
1132         }
1133
1134         if ( SLAP_ISGLOBALOVERLAY( be ) ) {
1135                 BackendDB *bd;
1136
1137                 /* remove from all backends... */
1138                 LDAP_STAILQ_FOREACH( bd, &backendDB, be_next ) {
1139                         if ( bd == be->bd_self ) {
1140                                 gotit = 1;
1141                         }
1142
1143                         bd->be_ctrls[ cid ]--;
1144                 }
1145         }
1146
1147         if ( !gotit ) {
1148                 be->bd_self->be_ctrls[ cid ]--;
1149         }
1150 }
1151 #endif /* SLAP_CONFIG_DELETE */
1152
1153 void
1154 overlay_destroy_one( BackendDB *be, slap_overinst *on )
1155 {
1156         slap_overinfo *oi = on->on_info;
1157         slap_overinst **oidx;
1158
1159         for ( oidx = &oi->oi_list; *oidx; oidx = &(*oidx)->on_next ) {
1160                 if ( *oidx == on ) {
1161                         *oidx = on->on_next;
1162                         if ( on->on_bi.bi_db_destroy ) {
1163                                 BackendInfo *bi_orig = be->bd_info;
1164                                 be->bd_info = (BackendInfo *)on;
1165                                 on->on_bi.bi_db_destroy( be, NULL );
1166                                 be->bd_info = bi_orig;
1167                         }
1168                         free( on );
1169                         break;
1170                 }
1171         }
1172 }
1173
1174 #ifdef SLAP_CONFIG_DELETE
1175 typedef struct ov_remove_ctx {
1176         BackendDB *be;
1177         slap_overinst *on;
1178 } ov_remove_ctx;
1179
1180 int
1181 overlay_remove_cb( Operation *op, SlapReply *rs )
1182 {
1183         ov_remove_ctx *rm_ctx = (ov_remove_ctx*) op->o_callback->sc_private;
1184         BackendInfo *bi_orig = rm_ctx->be->bd_info;
1185
1186         rm_ctx->be->bd_info = (BackendInfo*) rm_ctx->on;
1187
1188         if ( rm_ctx->on->on_bi.bi_db_close ) {
1189                 rm_ctx->on->on_bi.bi_db_close( rm_ctx->be, NULL );
1190         }
1191         if ( rm_ctx->on->on_bi.bi_db_destroy ) {
1192                 rm_ctx->on->on_bi.bi_db_destroy( rm_ctx->be, NULL );
1193         }
1194
1195         /* clean up after removing last overlay */
1196         if ( ! rm_ctx->on->on_info->oi_list ) {
1197                 /* reset db flags and bd_info to orig */
1198                 SLAP_DBFLAGS( rm_ctx->be ) &= ~SLAP_DBFLAG_GLOBAL_OVERLAY;
1199                 rm_ctx->be->bd_info = rm_ctx->on->on_info->oi_orig;
1200                 ch_free(rm_ctx->on->on_info);
1201         } else {
1202                 rm_ctx->be->bd_info = bi_orig;
1203         }
1204         free( rm_ctx->on );
1205         op->o_tmpfree(rm_ctx, op->o_tmpmemctx);
1206         return SLAP_CB_CONTINUE;
1207 }
1208
1209 void
1210 overlay_remove( BackendDB *be, slap_overinst *on, Operation *op )
1211 {
1212         slap_overinfo *oi = on->on_info;
1213         slap_overinst **oidx;
1214         ov_remove_ctx *rm_ctx;
1215         slap_callback *rm_cb, *cb;
1216
1217         /* remove overlay from oi_list */
1218         for ( oidx = &oi->oi_list; *oidx; oidx = &(*oidx)->on_next ) {
1219                 if ( *oidx == on ) {
1220                         *oidx = on->on_next;
1221                         break;
1222                 }
1223         }
1224
1225         /* The db_close and db_destroy handlers to cleanup a release
1226          * the overlay's resources are called from the cleanup callback
1227          */
1228         rm_ctx = op->o_tmpalloc( sizeof( ov_remove_ctx ), op->o_tmpmemctx );
1229         rm_ctx->be = be;
1230         rm_ctx->on = on;
1231
1232         rm_cb = op->o_tmpalloc( sizeof( slap_callback ), op->o_tmpmemctx );
1233         rm_cb->sc_next = NULL;
1234         rm_cb->sc_cleanup = overlay_remove_cb;
1235         rm_cb->sc_response = NULL;
1236         rm_cb->sc_private = (void*) rm_ctx;
1237
1238         /* Append callback to the end of the list */
1239         if ( !op->o_callback ) {
1240                 op->o_callback = rm_cb;
1241         } else {
1242                 for ( cb = op->o_callback; cb->sc_next; cb = cb->sc_next );
1243                 cb->sc_next = rm_cb;
1244         }
1245 }
1246 #endif /* SLAP_CONFIG_DELETE */
1247
1248 void
1249 overlay_insert( BackendDB *be, slap_overinst *on2, slap_overinst ***prev,
1250         int idx )
1251 {
1252         slap_overinfo *oi = (slap_overinfo *)be->bd_info;
1253
1254         if ( idx == -1 ) {
1255                 on2->on_next = oi->oi_list;
1256                 oi->oi_list = on2;
1257         } else {
1258                 int i, novs;
1259                 slap_overinst *on, **prev;
1260
1261                 /* Since the list is in reverse order and is singly linked,
1262                  * we have to count the overlays and then insert backwards.
1263                  * Adding on overlay at a specific point should be a pretty
1264                  * infrequent occurrence.
1265                  */
1266                 novs = 0;
1267                 for ( on = oi->oi_list; on; on=on->on_next )
1268                         novs++;
1269
1270                 if (idx > novs)
1271                         idx = 0;
1272                 else
1273                         idx = novs - idx;
1274
1275                 /* advance to insertion point */
1276                 prev = &oi->oi_list;
1277                 for ( i=0; i<idx; i++ ) {
1278                         on = *prev;
1279                         prev = &on->on_next;
1280                 }
1281                 /* insert */
1282                 on2->on_next = *prev;
1283                 *prev = on2;
1284         }
1285 }
1286
1287 void
1288 overlay_move( BackendDB *be, slap_overinst *on, int idx )
1289 {
1290         slap_overinfo *oi = (slap_overinfo *)be->bd_info;
1291         slap_overinst **onp;
1292
1293         for (onp = &oi->oi_list; *onp; onp= &(*onp)->on_next) {
1294                 if ( *onp == on ) {
1295                         *onp = on->on_next;
1296                         break;
1297                 }
1298         }
1299         overlay_insert( be, on, &onp, idx );
1300 }
1301
1302 /* add an overlay to a particular backend. */
1303 int
1304 overlay_config( BackendDB *be, const char *ov, int idx, BackendInfo **res, ConfigReply *cr )
1305 {
1306         slap_overinst *on = NULL, *on2 = NULL, **prev;
1307         slap_overinfo *oi = NULL;
1308         BackendInfo *bi = NULL;
1309
1310         if ( res )
1311                 *res = NULL;
1312
1313         on = overlay_find( ov );
1314         if ( !on ) {
1315                 Debug( LDAP_DEBUG_ANY, "overlay \"%s\" not found\n", ov, 0, 0 );
1316                 return 1;
1317         }
1318
1319         /* If this is the first overlay on this backend, set up the
1320          * overlay info structure
1321          */
1322         if ( !overlay_is_over( be ) ) {
1323                 int     isglobal = 0;
1324
1325                 /* NOTE: the first time a global overlay is configured,
1326                  * frontendDB gets this flag; it is used later by overlays
1327                  * to determine if they're stacked on top of the frontendDB */
1328                 if ( be->bd_info == frontendDB->bd_info || SLAP_ISGLOBALOVERLAY( be ) ) {
1329                         isglobal = 1;
1330                         if ( on->on_bi.bi_flags & SLAPO_BFLAG_DBONLY ) {
1331                                 Debug( LDAP_DEBUG_ANY, "overlay_config(): "
1332                                         "overlay \"%s\" cannot be global.\n",
1333                                         ov, 0, 0 );
1334                                 return 1;
1335                         }
1336
1337                 } else if ( on->on_bi.bi_flags & SLAPO_BFLAG_GLOBONLY ) {
1338                         Debug( LDAP_DEBUG_ANY, "overlay_config(): "
1339                                 "overlay \"%s\" can only be global.\n",
1340                                 ov, 0, 0 );
1341                         return 1;
1342                 }
1343
1344                 oi = ch_malloc( sizeof( slap_overinfo ) );
1345                 oi->oi_orig = be->bd_info;
1346                 oi->oi_bi = *be->bd_info;
1347                 oi->oi_origdb = be;
1348
1349                 if ( isglobal ) {
1350                         SLAP_DBFLAGS( be ) |= SLAP_DBFLAG_GLOBAL_OVERLAY;
1351                 }
1352
1353                 /* Save a pointer to ourself in bi_private.
1354                  */
1355                 oi->oi_bi.bi_private = oi;
1356                 oi->oi_list = NULL;
1357                 bi = (BackendInfo *)oi;
1358
1359                 bi->bi_type = (char *)overtype;
1360
1361                 bi->bi_db_config = over_db_config;
1362                 bi->bi_db_open = over_db_open;
1363                 bi->bi_db_close = over_db_close;
1364                 bi->bi_db_destroy = over_db_destroy;
1365
1366                 bi->bi_op_bind = over_op_bind;
1367                 bi->bi_op_unbind = over_op_unbind;
1368                 bi->bi_op_search = over_op_search;
1369                 bi->bi_op_compare = over_op_compare;
1370                 bi->bi_op_modify = over_op_modify;
1371                 bi->bi_op_modrdn = over_op_modrdn;
1372                 bi->bi_op_add = over_op_add;
1373                 bi->bi_op_delete = over_op_delete;
1374                 bi->bi_op_abandon = over_op_abandon;
1375                 bi->bi_op_cancel = over_op_cancel;
1376
1377                 bi->bi_extended = over_op_extended;
1378
1379                 /*
1380                  * this is fine because it has the same
1381                  * args of the operations; we need to rework
1382                  * all the hooks to share the same args
1383                  * of the operations...
1384                  */
1385                 bi->bi_operational = over_aux_operational;
1386                 bi->bi_chk_referrals = over_aux_chk_referrals;
1387                 bi->bi_chk_controls = over_aux_chk_controls;
1388
1389                 /* these have specific arglists */
1390                 bi->bi_entry_get_rw = over_entry_get_rw;
1391                 bi->bi_entry_release_rw = over_entry_release_rw;
1392                 bi->bi_access_allowed = over_access_allowed;
1393                 bi->bi_acl_group = over_acl_group;
1394                 bi->bi_acl_attribute = over_acl_attribute;
1395
1396                 bi->bi_connection_init = over_connection_init;
1397                 bi->bi_connection_destroy = over_connection_destroy;
1398
1399                 be->bd_info = bi;
1400
1401         } else {
1402                 if ( overlay_is_inst( be, ov ) ) {
1403                         if ( SLAPO_SINGLE( be ) ) {
1404                                 Debug( LDAP_DEBUG_ANY, "overlay_config(): "
1405                                         "overlay \"%s\" already in list\n",
1406                                         ov, 0, 0 );
1407                                 return 1;
1408                         }
1409                 }
1410
1411                 oi = be->bd_info->bi_private;
1412         }
1413
1414         /* Insert new overlay into list. By default overlays are
1415          * added to head of list and executed in LIFO order.
1416          */
1417         on2 = ch_calloc( 1, sizeof(slap_overinst) );
1418         *on2 = *on;
1419         on2->on_info = oi;
1420
1421         prev = &oi->oi_list;
1422         /* Do we need to find the insertion point? */
1423         if ( idx >= 0 ) {
1424                 int i;
1425
1426                 /* count current overlays */
1427                 for ( i=0, on=oi->oi_list; on; on=on->on_next, i++ );
1428
1429                 /* are we just appending a new one? */
1430                 if ( idx >= i )
1431                         idx = -1;
1432         }
1433         overlay_insert( be, on2, &prev, idx );
1434
1435         /* Any initialization needed? */
1436         if ( on2->on_bi.bi_db_init ) {
1437                 int rc;
1438                 be->bd_info = (BackendInfo *)on2;
1439                 rc = on2->on_bi.bi_db_init( be, cr);
1440                 be->bd_info = (BackendInfo *)oi;
1441                 if ( rc ) {
1442                         *prev = on2->on_next;
1443                         ch_free( on2 );
1444                         on2 = NULL;
1445                         return rc;
1446                 }
1447         }
1448
1449         if ( res )
1450                 *res = &on2->on_bi;
1451
1452         return 0;
1453 }