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

   1 /* backglue.c - backend glue routines */
   2 /* $OpenLDAP$ */
   3 /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
   4  *
   5  * Copyright 2001-2004 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 /*
  18  * Functions to glue a bunch of other backends into a single tree.
  19  * All of the glued backends must share a common suffix. E.g., you
  20  * can glue o=foo and ou=bar,o=foo but you can't glue o=foo and o=bar.
  21  *
  22  * This uses the backend structures and routines extensively, but is
  23  * not an actual backend of its own. To use it you must add a "subordinate"
  24  * keyword to the configuration of other backends. Subordinates will
  25  * automatically be connected to their parent backend.
  26  *
  27  * The purpose of these functions is to allow you to split a single database
  28  * into pieces (for load balancing purposes, whatever) but still be able
  29  * to treat it as a single database after it's been split. As such, each
  30  * of the glued backends should have identical rootdn and rootpw.
  31  *
  32  * If you need more elaborate configuration, you probably should be using
  33  * back-meta instead.
  34  *  -- Howard Chu
  35  */
  36
  37 #include "portable.h"
  38
  39 #include <stdio.h>
  40
  41 #include <ac/string.h>
  42 #include <ac/socket.h>
  43
  44 #define SLAPD_TOOLS
  45 #include "slap.h"
  46
  47 typedef struct gluenode {
  48         BackendDB *be;
  49         struct berval pdn;
  50 } gluenode;
  51
  52 typedef struct glueinfo {
  53         BackendInfo bi;
  54         BackendDB bd;
  55         int nodes;
  56         gluenode n[1];
  57 } glueinfo;
  58
  59 static int glueMode;
  60 static BackendDB *glueBack;
  61
  62 static slap_response glue_back_response;
  63
  64 /* Just like select_backend, but only for our backends */
  65 static BackendDB *
  66 glue_back_select (
  67         BackendDB *be,
  68         const char *dn
  69 )
  70 {
  71         glueinfo *gi = (glueinfo *) be->bd_info;
  72         struct berval bv;
  73         int i;
  74
  75         bv.bv_len = strlen(dn);
  76         bv.bv_val = (char *) dn;
  77
  78         for (i = 0; i<gi->nodes; i++) {
  79                 assert( gi->n[i].be->be_nsuffix );
  80
  81                 if (dnIsSuffix(&bv, &gi->n[i].be->be_nsuffix[0])) {
  82                         return gi->n[i].be;
  83                 }
  84         }
  85         return NULL;
  86 }
  87
  88 /* This function will only be called in tool mode */
  89 static int
  90 glue_back_open (
  91         BackendInfo *bi
  92 )
  93 {
  94         int rc = 0;
  95         static int glueOpened = 0;
  96
  97         if (glueOpened) return 0;
  98
  99         glueOpened = 1;
 100
 101         /* If we were invoked in tool mode, open all the underlying backends */
 102         if (slapMode & SLAP_TOOL_MODE) {
 103                 rc = backend_startup (NULL);
 104         } /* other case is impossible */
 105         return rc;
 106 }
 107
 108 /* This function will only be called in tool mode */
 109 static int
 110 glue_back_close (
 111         BackendInfo *bi
 112 )
 113 {
 114         static int glueClosed = 0;
 115         int rc = 0;
 116
 117         if (glueClosed) return 0;
 118
 119         glueClosed = 1;
 120
 121         if (slapMode & SLAP_TOOL_MODE) {
 122                 rc = backend_shutdown (NULL);
 123         }
 124         return rc;
 125 }
 126
 127 static int
 128 glue_back_db_open (
 129         BackendDB *be
 130 )
 131 {
 132         glueinfo *gi = (glueinfo *) be->bd_info;
 133         static int glueOpened = 0;
 134         int rc = 0;
 135
 136         if (glueOpened) return 0;
 137
 138         glueOpened = 1;
 139
 140         gi->bd.be_acl = be->be_acl;
 141
 142         if (gi->bd.bd_info->bi_db_open)
 143                 rc = gi->bd.bd_info->bi_db_open(&gi->bd);
 144
 145         return rc;
 146 }
 147
 148 static int
 149 glue_back_db_close (
 150         BackendDB *be
 151 )
 152 {
 153         glueinfo *gi = (glueinfo *) be->bd_info;
 154         static int glueClosed = 0;
 155
 156         if (glueClosed) return 0;
 157
 158         glueClosed = 1;
 159
 160         /* Close the master */
 161         if (gi->bd.bd_info->bi_db_close)
 162                 gi->bd.bd_info->bi_db_close( &gi->bd );
 163
 164         return 0;
 165 }
 166
 167 static int
 168 glue_back_db_destroy (
 169         BackendDB *be
 170 )
 171 {
 172         glueinfo *gi = (glueinfo *) be->bd_info;
 173
 174         if (gi->bd.bd_info->bi_db_destroy)
 175                 gi->bd.bd_info->bi_db_destroy( &gi->bd );
 176         free (gi);
 177         return 0;
 178 }
 179
 180 typedef struct glue_state {
 181         int err;
 182         int is_slimit;
 183         int slimit;
 184         int matchlen;
 185         char *matched;
 186         int nrefs;
 187         BerVarray refs;
 188 } glue_state;
 189
 190 static int
 191 glue_back_response ( Operation *op, SlapReply *rs )
 192 {
 193         glue_state *gs = op->o_callback->sc_private;
 194
 195         switch(rs->sr_type) {
 196         case REP_SEARCH:
 197                 if ( gs->is_slimit && rs->sr_nentries >= gs->slimit ) {
 198                         gs->err = LDAP_SIZELIMIT_EXCEEDED;
 199                         return -1;
 200                 }
 201                 /* fallthru */
 202         case REP_SEARCHREF:
 203                 return SLAP_CB_CONTINUE;
 204
 205         default:
 206                 if ( gs->is_slimit && rs->sr_err == LDAP_SIZELIMIT_EXCEEDED
 207                                 && rs->sr_nentries >= gs->slimit ) {
 208                         gs->err = LDAP_SIZELIMIT_EXCEEDED;
 209                         return -1;
 210                 }
 211                 if (rs->sr_err == LDAP_SUCCESS || gs->err != LDAP_SUCCESS) {
 212                         gs->err = rs->sr_err;
 213                 }
 214                 if (gs->err == LDAP_SUCCESS && gs->matched) {
 215                         ch_free (gs->matched);
 216                         gs->matched = NULL;
 217                         gs->matchlen = 0;
 218                 }
 219                 if (gs->err != LDAP_SUCCESS && rs->sr_matched) {
 220                         int len;
 221                         len = strlen (rs->sr_matched);
 222                         if (len > gs->matchlen) {
 223                                 if (gs->matched)
 224                                         ch_free (gs->matched);
 225                                 gs->matched = ch_strdup (rs->sr_matched);
 226                                 gs->matchlen = len;
 227                         }
 228                 }
 229                 if (rs->sr_ref) {
 230                         int i, j, k;
 231                         BerVarray new;
 232
 233                         for (i=0; rs->sr_ref[i].bv_val; i++);
 234
 235                         j = gs->nrefs;
 236                         if (!j) {
 237                                 new = ch_malloc ((i+1)*sizeof(struct berval));
 238                         } else {
 239                                 new = ch_realloc(gs->refs,
 240                                         (j+i+1)*sizeof(struct berval));
 241                         }
 242                         for (k=0; k<i; j++,k++) {
 243                                 ber_dupbv( &new[j], &rs->sr_ref[k] );
 244                         }
 245                         new[j].bv_val = NULL;
 246                         gs->nrefs = j;
 247                         gs->refs = new;
 248                 }
 249         }
 250         return 0;
 251 }
 252
 253 static int
 254 glue_back_search ( Operation *op, SlapReply *rs )
 255 {
 256         BackendDB *b0 = op->o_bd;
 257         glueinfo *gi = (glueinfo *) b0->bd_info;
 258         int i;
 259         long stoptime = 0;
 260         glue_state gs = {0, 0, 0, 0, NULL, 0, NULL};
 261         slap_callback cb = { NULL, glue_back_response, NULL, NULL };
 262         int scope0, slimit0, tlimit0;
 263         struct berval dn, ndn;
 264
 265         gs.is_slimit = ( op->ors_slimit > 0 );
 266
 267         cb.sc_private = &gs;
 268
 269         cb.sc_next = op->o_callback;
 270
 271         if (op->ors_tlimit) {
 272                 stoptime = slap_get_time () + op->ors_tlimit;
 273         }
 274
 275         switch (op->ors_scope) {
 276         case LDAP_SCOPE_BASE:
 277                 op->o_bd = glue_back_select (b0, op->o_req_ndn.bv_val);
 278
 279                 if (op->o_bd && op->o_bd->be_search) {
 280                         rs->sr_err = op->o_bd->be_search( op, rs );
 281                 } else {
 282                         send_ldap_error(op, rs, LDAP_UNWILLING_TO_PERFORM,
 283                                       "No search target found");
 284                 }
 285                 return rs->sr_err;
 286
 287         case LDAP_SCOPE_ONELEVEL:
 288         case LDAP_SCOPE_SUBTREE:
 289         case LDAP_SCOPE_SUBORDINATE: /* FIXME */
 290                 op->o_callback = &cb;
 291                 rs->sr_err = gs.err = LDAP_UNWILLING_TO_PERFORM;
 292                 scope0 = op->ors_scope;
 293                 if ( gs.is_slimit ) {
 294                         slimit0 = gs.slimit = op->ors_slimit;
 295                 }
 296                 tlimit0 = op->ors_tlimit;
 297                 dn = op->o_req_dn;
 298                 ndn = op->o_req_ndn;
 299
 300                 /*
 301                  * Execute in reverse order, most general first
 302                  */
 303                 for (i = gi->nodes-1; i >= 0; i--) {
 304                         if (!gi->n[i].be || !gi->n[i].be->be_search)
 305                                 continue;
 306                         if (tlimit0) {
 307                                 op->ors_tlimit = stoptime - slap_get_time ();
 308                                 if (op->ors_tlimit <= 0) {
 309                                         rs->sr_err = gs.err = LDAP_TIMELIMIT_EXCEEDED;
 310                                         break;
 311                                 }
 312                         }
 313                         if ( gs.is_slimit ) {
 314                                 op->ors_slimit = slimit0 - rs->sr_nentries;
 315                                 if (op->ors_slimit < 0) {
 316                                         rs->sr_err = gs.err = LDAP_SIZELIMIT_EXCEEDED;
 317                                         break;
 318                                 }
 319                         }
 320                         rs->sr_err = 0;
 321                         /*
 322                          * check for abandon
 323                          */
 324                         if (op->o_abandon) {
 325                                 goto done;
 326                         }
 327                         op->o_bd = gi->n[i].be;
 328
 329                         assert( op->o_bd->be_suffix );
 330                         assert( op->o_bd->be_nsuffix );
 331
 332                         if (scope0 == LDAP_SCOPE_ONELEVEL &&
 333                                 dn_match(&gi->n[i].pdn, &ndn))
 334                         {
 335                                 op->ors_scope = LDAP_SCOPE_BASE;
 336                                 op->o_req_dn = op->o_bd->be_suffix[0];
 337                                 op->o_req_ndn = op->o_bd->be_nsuffix[0];
 338                                 rs->sr_err = op->o_bd->be_search(op, rs);
 339
 340                         } else if (scope0 == LDAP_SCOPE_SUBTREE &&
 341                                 dnIsSuffix(&op->o_bd->be_nsuffix[0], &ndn))
 342                         {
 343                                 op->o_req_dn = op->o_bd->be_suffix[0];
 344                                 op->o_req_ndn = op->o_bd->be_nsuffix[0];
 345                                 rs->sr_err = op->o_bd->be_search( op, rs );
 346
 347                         } else if (dnIsSuffix(&ndn, &op->o_bd->be_nsuffix[0])) {
 348                                 rs->sr_err = op->o_bd->be_search( op, rs );
 349                         }
 350
 351                         switch ( gs.err ) {
 352
 353                         /*
 354                          * Add errors that should result in dropping
 355                          * the search
 356                          */
 357                         case LDAP_SIZELIMIT_EXCEEDED:
 358                         case LDAP_TIMELIMIT_EXCEEDED:
 359                         case LDAP_ADMINLIMIT_EXCEEDED:
 360                                 goto end_of_loop;
 361
 362                         default:
 363                                 break;
 364                         }
 365                 }
 366 end_of_loop:;
 367                 op->ors_scope = scope0;
 368                 if ( gs.is_slimit ) {
 369                         op->ors_slimit = slimit0;
 370                 }
 371                 op->ors_tlimit = tlimit0;
 372                 op->o_req_dn = dn;
 373                 op->o_req_ndn = ndn;
 374
 375                 break;
 376         }
 377         op->o_callback = cb.sc_next;
 378         rs->sr_err = gs.err;
 379         rs->sr_matched = gs.matched;
 380         rs->sr_ref = gs.refs;
 381
 382         send_ldap_result( op, rs );
 383
 384 done:
 385         op->o_bd = b0;
 386         if (gs.matched)
 387                 free (gs.matched);
 388         if (gs.refs)
 389                 ber_bvarray_free(gs.refs);
 390         return rs->sr_err;
 391 }
 392
 393
 394 static int
 395 glue_tool_entry_open (
 396         BackendDB *b0,
 397         int mode
 398 )
 399 {
 400         /* We don't know which backend to talk to yet, so just
 401          * remember the mode and move on...
 402          */
 403
 404         glueMode = mode;
 405         glueBack = NULL;
 406
 407         return 0;
 408 }
 409
 410 static int
 411 glue_tool_entry_close (
 412         BackendDB *b0
 413 )
 414 {
 415         int rc = 0;
 416
 417         if (glueBack) {
 418                 if (!glueBack->be_entry_close)
 419                         return 0;
 420                 rc = glueBack->be_entry_close (glueBack);
 421         }
 422         return rc;
 423 }
 424
 425 static ID
 426 glue_tool_entry_first (
 427         BackendDB *b0
 428 )
 429 {
 430         glueinfo *gi = (glueinfo *) b0->bd_info;
 431         int i;
 432
 433         /* If we're starting from scratch, start at the most general */
 434         if (!glueBack) {
 435                 for (i = gi->nodes-1; i >= 0; i--) {
 436                         if (gi->n[i].be->be_entry_open &&
 437                             gi->n[i].be->be_entry_first) {
 438                                 glueBack = gi->n[i].be;
 439                                 break;
 440                         }
 441                 }
 442
 443         }
 444         if (!glueBack || glueBack->be_entry_open (glueBack, glueMode) != 0)
 445                 return NOID;
 446
 447         return glueBack->be_entry_first (glueBack);
 448 }
 449
 450 static ID
 451 glue_tool_entry_next (
 452         BackendDB *b0
 453 )
 454 {
 455         glueinfo *gi = (glueinfo *) b0->bd_info;
 456         int i;
 457         ID rc;
 458
 459         if (!glueBack || !glueBack->be_entry_next)
 460                 return NOID;
 461
 462         rc = glueBack->be_entry_next (glueBack);
 463
 464         /* If we ran out of entries in one database, move on to the next */
 465         if (rc == NOID) {
 466                 glueBack->be_entry_close (glueBack);
 467                 for (i=0; i<gi->nodes; i++) {
 468                         if (gi->n[i].be == glueBack)
 469                                 break;
 470                 }
 471                 if (i == 0) {
 472                         glueBack = NULL;
 473                         rc = NOID;
 474                 } else {
 475                         glueBack = gi->n[i-1].be;
 476                         rc = glue_tool_entry_first (b0);
 477                 }
 478         }
 479         return rc;
 480 }
 481
 482 static Entry *
 483 glue_tool_entry_get (
 484         BackendDB *b0,
 485         ID id
 486 )
 487 {
 488         if (!glueBack || !glueBack->be_entry_get)
 489                 return NULL;
 490
 491         return glueBack->be_entry_get (glueBack, id);
 492 }
 493
 494 static ID
 495 glue_tool_entry_put (
 496         BackendDB *b0,
 497         Entry *e,
 498         struct berval *text
 499 )
 500 {
 501         BackendDB *be;
 502         int rc;
 503
 504         be = glue_back_select (b0, e->e_ndn);
 505         if (!be->be_entry_put)
 506                 return NOID;
 507
 508         if (!glueBack) {
 509                 rc = be->be_entry_open (be, glueMode);
 510                 if (rc != 0)
 511                         return NOID;
 512         } else if (be != glueBack) {
 513                 /* If this entry belongs in a different branch than the
 514                  * previous one, close the current database and open the
 515                  * new one.
 516                  */
 517                 glueBack->be_entry_close (glueBack);
 518                 rc = be->be_entry_open (be, glueMode);
 519                 if (rc != 0)
 520                         return NOID;
 521         }
 522         glueBack = be;
 523         return be->be_entry_put (be, e, text);
 524 }
 525
 526 static int
 527 glue_tool_entry_reindex (
 528         BackendDB *b0,
 529         ID id
 530 )
 531 {
 532         if (!glueBack || !glueBack->be_entry_reindex)
 533                 return -1;
 534
 535         return glueBack->be_entry_reindex (glueBack, id);
 536 }
 537
 538 static int
 539 glue_tool_sync (
 540         BackendDB *b0
 541 )
 542 {
 543         glueinfo *gi = (glueinfo *) b0->bd_info;
 544         int i;
 545
 546         /* just sync everyone */
 547         for (i = 0; i<gi->nodes; i++)
 548                 if (gi->n[i].be->be_sync)
 549                         gi->n[i].be->be_sync (gi->n[i].be);
 550         return 0;
 551 }
 552
 553 int
 554 glue_sub_init( )
 555 {
 556         int i, j;
 557         int cont = num_subordinates;
 558         BackendDB *b1, *be;
 559         BackendInfo *bi = NULL;
 560         glueinfo *gi;
 561
 562         /* While there are subordinate backends, search backwards through the
 563          * backends and connect them to their superior.
 564          */
 565         for (i = nBackendDB - 1, b1=&backendDB[i]; cont && i>=0; b1--,i--) {
 566                 if (SLAP_GLUE_SUBORDINATE ( b1 ) ) {
 567                         /* The last database cannot be a subordinate of noone */
 568                         if (i == nBackendDB - 1) {
 569                                 b1->be_flags ^= SLAP_BFLAG_GLUE_SUBORDINATE;
 570                         }
 571                         continue;
 572                 }
 573                 gi = NULL;
 574                 for (j = i-1, be=&backendDB[j]; j>=0; be--,j--) {
 575                         if ( ! SLAP_GLUE_SUBORDINATE( be ) ) {
 576                                 continue;
 577                         }
 578                         /* We will only link it once */
 579                         if ( SLAP_GLUE_LINKED( be ) ) {
 580                                 continue;
 581                         }
 582                         assert( be->be_nsuffix );
 583                         assert( b1->be_nsuffix );
 584                         if (!dnIsSuffix(&be->be_nsuffix[0], &b1->be_nsuffix[0])) {
 585                                 continue;
 586                         }
 587                         cont--;
 588                         be->be_flags |= SLAP_BFLAG_GLUE_LINKED;
 589                         if (gi == NULL) {
 590                                 /* We create a copy of the superior's be
 591                                  * structure, pointing to all of its original
 592                                  * information. Then we replace elements of
 593                                  * the superior's info with our own. The copy
 594                                  * is used whenever we have operations to pass
 595                                  * down to the real database.
 596                                  */
 597                                 b1->be_flags |= SLAP_BFLAG_GLUE_INSTANCE;
 598                                 gi = (glueinfo *)ch_malloc(sizeof(glueinfo));
 599                                 gi->nodes = 0;
 600                                 gi->bd = *b1;
 601                                 gi->bi = *b1->bd_info;
 602                                 bi = (BackendInfo *)gi;
 603                                 bi->bi_open = glue_back_open;
 604                                 bi->bi_close = glue_back_close;
 605                                 bi->bi_db_open = glue_back_db_open;
 606                                 bi->bi_db_close = glue_back_db_close;
 607                                 bi->bi_db_destroy = glue_back_db_destroy;
 608
 609                                 bi->bi_op_search = glue_back_search;
 610
 611                                 /*
 612                                  * hooks for slap tools
 613                                  */
 614                                 bi->bi_tool_entry_open = glue_tool_entry_open;
 615                                 bi->bi_tool_entry_close = glue_tool_entry_close;
 616                                 bi->bi_tool_entry_first = glue_tool_entry_first;
 617                                 bi->bi_tool_entry_next = glue_tool_entry_next;
 618                                 bi->bi_tool_entry_get = glue_tool_entry_get;
 619                                 bi->bi_tool_entry_put = glue_tool_entry_put;
 620                                 bi->bi_tool_entry_reindex = glue_tool_entry_reindex;
 621                                 bi->bi_tool_sync = glue_tool_sync;
 622                                 /* FIXME : will support later */
 623                                 bi->bi_tool_dn2id_get = 0;
 624                                 bi->bi_tool_id2entry_get = 0;
 625                                 bi->bi_tool_entry_modify = 0;
 626                         } else {
 627                                 gi = (glueinfo *)ch_realloc(gi,
 628                                         sizeof(glueinfo) +
 629                                         gi->nodes * sizeof(gluenode));
 630                         }
 631                         gi->n[gi->nodes].be = be;
 632                         dnParent( &be->be_nsuffix[0], &gi->n[gi->nodes].pdn );
 633                         gi->nodes++;
 634                 }
 635                 if (gi) {
 636                         /* One more node for the master */
 637                         gi = (glueinfo *)ch_realloc(gi,
 638                                 sizeof(glueinfo) + gi->nodes * sizeof(gluenode));
 639                         gi->n[gi->nodes].be = &gi->bd;
 640                         dnParent( &b1->be_nsuffix[0], &gi->n[gi->nodes].pdn );
 641                         gi->nodes++;
 642                         b1->bd_info = (BackendInfo *)gi;
 643                 }
 644         }
 645         /* If there are any unresolved subordinates left, something is wrong */
 646         return cont;
 647 }