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         gi->bd.be_pending_csn_list = be->be_pending_csn_list;
 142
 143         if (gi->bd.bd_info->bi_db_open)
 144                 rc = gi->bd.bd_info->bi_db_open(&gi->bd);
 145
 146         return rc;
 147 }
 148
 149 static int
 150 glue_back_db_close (
 151         BackendDB *be
 152 )
 153 {
 154         glueinfo *gi = (glueinfo *) be->bd_info;
 155         static int glueClosed = 0;
 156
 157         if (glueClosed) return 0;
 158
 159         glueClosed = 1;
 160
 161         /* Close the master */
 162         if (gi->bd.bd_info->bi_db_close)
 163                 gi->bd.bd_info->bi_db_close( &gi->bd );
 164
 165         return 0;
 166 }
 167
 168 static int
 169 glue_back_db_destroy (
 170         BackendDB *be
 171 )
 172 {
 173         glueinfo *gi = (glueinfo *) be->bd_info;
 174
 175         if (gi->bd.bd_info->bi_db_destroy)
 176                 gi->bd.bd_info->bi_db_destroy( &gi->bd );
 177         free (gi);
 178         return 0;
 179 }
 180
 181 typedef struct glue_state {
 182         int err;
 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->slimit != -1 && rs->sr_nentries >= gs->slimit ) {
 198                         rs->sr_err = 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 (rs->sr_err == LDAP_SUCCESS ||
 207                         rs->sr_err == LDAP_SIZELIMIT_EXCEEDED ||
 208                         rs->sr_err == LDAP_TIMELIMIT_EXCEEDED ||
 209                         rs->sr_err == LDAP_ADMINLIMIT_EXCEEDED ||
 210                         rs->sr_err == LDAP_NO_SUCH_OBJECT ||
 211                         gs->err != LDAP_SUCCESS)
 212                         gs->err = rs->sr_err;
 213                 if (gs->err == LDAP_SUCCESS && gs->matched) {
 214                         ch_free (gs->matched);
 215                         gs->matched = NULL;
 216                         gs->matchlen = 0;
 217                 }
 218                 if (gs->err != LDAP_SUCCESS && rs->sr_matched) {
 219                         int len;
 220                         len = strlen (rs->sr_matched);
 221                         if (len > gs->matchlen) {
 222                                 if (gs->matched)
 223                                         ch_free (gs->matched);
 224                                 gs->matched = ch_strdup (rs->sr_matched);
 225                                 gs->matchlen = len;
 226                         }
 227                 }
 228                 if (rs->sr_ref) {
 229                         int i, j, k;
 230                         BerVarray new;
 231
 232                         for (i=0; rs->sr_ref[i].bv_val; i++);
 233
 234                         j = gs->nrefs;
 235                         if (!j) {
 236                                 new = ch_malloc ((i+1)*sizeof(struct berval));
 237                         } else {
 238                                 new = ch_realloc(gs->refs,
 239                                         (j+i+1)*sizeof(struct berval));
 240                         }
 241                         for (k=0; k<i; j++,k++) {
 242                                 ber_dupbv( &new[j], &rs->sr_ref[k] );
 243                         }
 244                         new[j].bv_val = NULL;
 245                         gs->nrefs = j;
 246                         gs->refs = new;
 247                 }
 248         }
 249         return 0;
 250 }
 251
 252 static int
 253 glue_back_search ( Operation *op, SlapReply *rs )
 254 {
 255         BackendDB *b0 = op->o_bd;
 256         BackendDB *b1 = NULL;
 257         glueinfo *gi = (glueinfo *) b0->bd_info;
 258         int i;
 259         long stoptime = 0;
 260         glue_state gs = {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         cb.sc_private = &gs;
 266
 267         cb.sc_next = op->o_callback;
 268
 269         stoptime = slap_get_time () + op->ors_tlimit;
 270
 271         op->o_bd = glue_back_select (b0, op->o_req_ndn.bv_val);
 272
 273         switch (op->ors_scope) {
 274         case LDAP_SCOPE_BASE:
 275                 if (op->o_bd && op->o_bd->be_search) {
 276                         rs->sr_err = op->o_bd->be_search( op, rs );
 277                 } else {
 278                         send_ldap_error(op, rs, LDAP_UNWILLING_TO_PERFORM,
 279                                       "No search target found");
 280                 }
 281                 return rs->sr_err;
 282
 283         case LDAP_SCOPE_ONELEVEL:
 284         case LDAP_SCOPE_SUBTREE:
 285 #ifdef LDAP_SCOPE_SUBORDINATE
 286         case LDAP_SCOPE_SUBORDINATE: /* FIXME */
 287 #endif
 288
 289                 if ( op->o_sync_mode & SLAP_SYNC_REFRESH ) {
 290                         if (op->o_bd && op->o_bd->be_search) {
 291                                 rs->sr_err = op->o_bd->be_search( op, rs );
 292                         } else {
 293                                 send_ldap_error(op, rs, LDAP_UNWILLING_TO_PERFORM,
 294                                               "No search target found");
 295                         }
 296                         return rs->sr_err;
 297                 }
 298
 299                 op->o_callback = &cb;
 300                 rs->sr_err = gs.err = LDAP_UNWILLING_TO_PERFORM;
 301                 scope0 = op->ors_scope;
 302                 slimit0 = gs.slimit = op->ors_slimit;
 303                 tlimit0 = op->ors_tlimit;
 304                 dn = op->o_req_dn;
 305                 ndn = op->o_req_ndn;
 306                 b1 = op->o_bd;
 307
 308                 /*
 309                  * Execute in reverse order, most general first
 310                  */
 311                 for (i = gi->nodes-1; i >= 0; i--) {
 312                         if (!gi->n[i].be || !gi->n[i].be->be_search)
 313                                 continue;
 314                         if (!dnIsSuffix(&gi->n[i].be->be_nsuffix[0], &b1->be_nsuffix[0]))
 315                                 continue;
 316                         if (tlimit0 != -1) {
 317                                 op->ors_tlimit = stoptime - slap_get_time ();
 318                                 if (op->ors_tlimit <= 0) {
 319                                         rs->sr_err = gs.err = LDAP_TIMELIMIT_EXCEEDED;
 320                                         break;
 321                                 }
 322                         }
 323                         if (slimit0 != -1) {
 324                                 op->ors_slimit = slimit0 - rs->sr_nentries;
 325                                 if (op->ors_slimit < 0) {
 326                                         rs->sr_err = gs.err = LDAP_SIZELIMIT_EXCEEDED;
 327                                         break;
 328                                 }
 329                         }
 330                         rs->sr_err = 0;
 331                         /*
 332                          * check for abandon
 333                          */
 334                         if (op->o_abandon) {
 335                                 goto end_of_loop;
 336                         }
 337                         op->o_bd = gi->n[i].be;
 338
 339                         assert( op->o_bd->be_suffix );
 340                         assert( op->o_bd->be_nsuffix );
 341
 342                         if (scope0 == LDAP_SCOPE_ONELEVEL &&
 343                                 dn_match(&gi->n[i].pdn, &ndn))
 344                         {
 345                                 op->ors_scope = LDAP_SCOPE_BASE;
 346                                 op->o_req_dn = op->o_bd->be_suffix[0];
 347                                 op->o_req_ndn = op->o_bd->be_nsuffix[0];
 348                                 rs->sr_err = op->o_bd->be_search(op, rs);
 349
 350                         } else if (scope0 == LDAP_SCOPE_SUBTREE &&
 351                                 dnIsSuffix(&op->o_bd->be_nsuffix[0], &ndn))
 352                         {
 353                                 op->o_req_dn = op->o_bd->be_suffix[0];
 354                                 op->o_req_ndn = op->o_bd->be_nsuffix[0];
 355                                 rs->sr_err = op->o_bd->be_search( op, rs );
 356
 357                         } else if (dnIsSuffix(&ndn, &op->o_bd->be_nsuffix[0])) {
 358                                 rs->sr_err = op->o_bd->be_search( op, rs );
 359                         }
 360
 361                         switch ( gs.err ) {
 362
 363                         /*
 364                          * Add errors that should result in dropping
 365                          * the search
 366                          */
 367                         case LDAP_SIZELIMIT_EXCEEDED:
 368                         case LDAP_TIMELIMIT_EXCEEDED:
 369                         case LDAP_ADMINLIMIT_EXCEEDED:
 370                         case LDAP_NO_SUCH_OBJECT:
 371                                 goto end_of_loop;
 372
 373                         default:
 374                                 break;
 375                         }
 376                 }
 377 end_of_loop:;
 378                 op->ors_scope = scope0;
 379                 op->ors_slimit = slimit0;
 380                 op->ors_tlimit = tlimit0;
 381                 op->o_req_dn = dn;
 382                 op->o_req_ndn = ndn;
 383
 384                 break;
 385         }
 386         if ( !op->o_abandon ) {
 387                 op->o_callback = cb.sc_next;
 388                 rs->sr_err = gs.err;
 389                 rs->sr_matched = gs.matched;
 390                 rs->sr_ref = gs.refs;
 391
 392                 send_ldap_result( op, rs );
 393         }
 394
 395         op->o_bd = b0;
 396         if (gs.matched)
 397                 free (gs.matched);
 398         if (gs.refs)
 399                 ber_bvarray_free(gs.refs);
 400         return rs->sr_err;
 401 }
 402
 403
 404 static int
 405 glue_tool_entry_open (
 406         BackendDB *b0,
 407         int mode
 408 )
 409 {
 410         /* We don't know which backend to talk to yet, so just
 411          * remember the mode and move on...
 412          */
 413
 414         glueMode = mode;
 415         glueBack = NULL;
 416
 417         return 0;
 418 }
 419
 420 static int
 421 glue_tool_entry_close (
 422         BackendDB *b0
 423 )
 424 {
 425         int rc = 0;
 426
 427         if (glueBack) {
 428                 if (!glueBack->be_entry_close)
 429                         return 0;
 430                 rc = glueBack->be_entry_close (glueBack);
 431         }
 432         return rc;
 433 }
 434
 435 static ID
 436 glue_tool_entry_first (
 437         BackendDB *b0
 438 )
 439 {
 440         glueinfo *gi = (glueinfo *) b0->bd_info;
 441         int i;
 442
 443         /* If we're starting from scratch, start at the most general */
 444         if (!glueBack) {
 445                 for (i = gi->nodes-1; i >= 0; i--) {
 446                         if (gi->n[i].be->be_entry_open &&
 447                             gi->n[i].be->be_entry_first) {
 448                                 glueBack = gi->n[i].be;
 449                                 break;
 450                         }
 451                 }
 452
 453         }
 454         if (!glueBack || !glueBack->be_entry_open || !glueBack->be_entry_first ||
 455                 glueBack->be_entry_open (glueBack, glueMode) != 0)
 456                 return NOID;
 457
 458         return glueBack->be_entry_first (glueBack);
 459 }
 460
 461 static ID
 462 glue_tool_entry_next (
 463         BackendDB *b0
 464 )
 465 {
 466         glueinfo *gi = (glueinfo *) b0->bd_info;
 467         int i;
 468         ID rc;
 469
 470         if (!glueBack || !glueBack->be_entry_next)
 471                 return NOID;
 472
 473         rc = glueBack->be_entry_next (glueBack);
 474
 475         /* If we ran out of entries in one database, move on to the next */
 476         while (rc == NOID) {
 477                 if ( glueBack && glueBack->be_entry_close )
 478                         glueBack->be_entry_close (glueBack);
 479                 for (i=0; i<gi->nodes; i++) {
 480                         if (gi->n[i].be == glueBack)
 481                                 break;
 482                 }
 483                 if (i == 0) {
 484                         glueBack = NULL;
 485                         break;
 486                 } else {
 487                         glueBack = gi->n[i-1].be;
 488                         rc = glue_tool_entry_first (b0);
 489                 }
 490         }
 491         return rc;
 492 }
 493
 494 static Entry *
 495 glue_tool_entry_get (
 496         BackendDB *b0,
 497         ID id
 498 )
 499 {
 500         if (!glueBack || !glueBack->be_entry_get)
 501                 return NULL;
 502
 503         return glueBack->be_entry_get (glueBack, id);
 504 }
 505
 506 static ID
 507 glue_tool_entry_put (
 508         BackendDB *b0,
 509         Entry *e,
 510         struct berval *text
 511 )
 512 {
 513         BackendDB *be;
 514         int rc;
 515
 516         be = glue_back_select (b0, e->e_ndn);
 517         if (!be->be_entry_put)
 518                 return NOID;
 519
 520         if (!glueBack) {
 521                 rc = be->be_entry_open (be, glueMode);
 522                 if (rc != 0)
 523                         return NOID;
 524         } else if (be != glueBack) {
 525                 /* If this entry belongs in a different branch than the
 526                  * previous one, close the current database and open the
 527                  * new one.
 528                  */
 529                 glueBack->be_entry_close (glueBack);
 530                 rc = be->be_entry_open (be, glueMode);
 531                 if (rc != 0)
 532                         return NOID;
 533         }
 534         glueBack = be;
 535         return be->be_entry_put (be, e, text);
 536 }
 537
 538 static int
 539 glue_tool_entry_reindex (
 540         BackendDB *b0,
 541         ID id
 542 )
 543 {
 544         if (!glueBack || !glueBack->be_entry_reindex)
 545                 return -1;
 546
 547         return glueBack->be_entry_reindex (glueBack, id);
 548 }
 549
 550 static int
 551 glue_tool_sync (
 552         BackendDB *b0
 553 )
 554 {
 555         glueinfo *gi = (glueinfo *) b0->bd_info;
 556         int i;
 557
 558         /* just sync everyone */
 559         for (i = 0; i<gi->nodes; i++)
 560                 if (gi->n[i].be->be_sync)
 561                         gi->n[i].be->be_sync (gi->n[i].be);
 562         return 0;
 563 }
 564
 565 int
 566 glue_sub_init( )
 567 {
 568         int i, j;
 569         int cont = num_subordinates;
 570         BackendDB *b1, *be;
 571         BackendInfo *bi = NULL;
 572         glueinfo *gi;
 573
 574         /* While there are subordinate backends, search backwards through the
 575          * backends and connect them to their superior.
 576          */
 577         for (i = nBackendDB - 1, b1=&backendDB[i]; cont && i>=0; b1--,i--) {
 578                 if (SLAP_GLUE_SUBORDINATE ( b1 ) ) {
 579                         /* The last database cannot be a subordinate of noone */
 580                         if (i == nBackendDB - 1) {
 581                                 SLAP_DBFLAGS(b1) ^= SLAP_DBFLAG_GLUE_SUBORDINATE;
 582                         }
 583                         continue;
 584                 }
 585                 gi = NULL;
 586                 for (j = i-1, be=&backendDB[j]; j>=0; be--,j--) {
 587                         if ( ! SLAP_GLUE_SUBORDINATE( be ) ) {
 588                                 continue;
 589                         }
 590                         /* We will only link it once */
 591                         if ( SLAP_GLUE_LINKED( be ) ) {
 592                                 continue;
 593                         }
 594                         assert( be->be_nsuffix );
 595                         assert( b1->be_nsuffix );
 596                         if (!dnIsSuffix(&be->be_nsuffix[0], &b1->be_nsuffix[0])) {
 597                                 continue;
 598                         }
 599                         cont--;
 600                         SLAP_DBFLAGS(be) |= SLAP_DBFLAG_GLUE_LINKED;
 601                         if (gi == NULL) {
 602                                 /* We create a copy of the superior's be
 603                                  * structure, pointing to all of its original
 604                                  * information. Then we replace elements of
 605                                  * the superior's info with our own. The copy
 606                                  * is used whenever we have operations to pass
 607                                  * down to the real database.
 608                                  */
 609                                 SLAP_DBFLAGS(b1) |= SLAP_DBFLAG_GLUE_INSTANCE;
 610                                 gi = (glueinfo *)ch_malloc(sizeof(glueinfo));
 611                                 gi->nodes = 0;
 612                                 gi->bd = *b1;
 613                                 gi->bi = *b1->bd_info;
 614                                 bi = (BackendInfo *)gi;
 615                                 bi->bi_open = glue_back_open;
 616                                 bi->bi_close = glue_back_close;
 617                                 bi->bi_db_open = glue_back_db_open;
 618                                 bi->bi_db_close = glue_back_db_close;
 619                                 bi->bi_db_destroy = glue_back_db_destroy;
 620
 621                                 bi->bi_op_search = glue_back_search;
 622
 623                                 /*
 624                                  * hooks for slap tools
 625                                  */
 626                                 bi->bi_tool_entry_open = glue_tool_entry_open;
 627                                 bi->bi_tool_entry_close = glue_tool_entry_close;
 628                                 bi->bi_tool_entry_first = glue_tool_entry_first;
 629                                 bi->bi_tool_entry_next = glue_tool_entry_next;
 630                                 bi->bi_tool_entry_get = glue_tool_entry_get;
 631                                 bi->bi_tool_entry_put = glue_tool_entry_put;
 632                                 bi->bi_tool_entry_reindex = glue_tool_entry_reindex;
 633                                 bi->bi_tool_sync = glue_tool_sync;
 634                                 /* FIXME : will support later */
 635                                 bi->bi_tool_dn2id_get = 0;
 636                                 bi->bi_tool_id2entry_get = 0;
 637                                 bi->bi_tool_entry_modify = 0;
 638                         } else {
 639                                 gi = (glueinfo *)ch_realloc(gi,
 640                                         sizeof(glueinfo) +
 641                                         gi->nodes * sizeof(gluenode));
 642                         }
 643                         gi->n[gi->nodes].be = be;
 644                         dnParent( &be->be_nsuffix[0], &gi->n[gi->nodes].pdn );
 645                         gi->nodes++;
 646                 }
 647                 if (gi) {
 648                         /* One more node for the master */
 649                         gi = (glueinfo *)ch_realloc(gi,
 650                                 sizeof(glueinfo) + gi->nodes * sizeof(gluenode));
 651                         gi->n[gi->nodes].be = &gi->bd;
 652                         dnParent( &b1->be_nsuffix[0], &gi->n[gi->nodes].pdn );
 653                         gi->nodes++;
 654                         b1->bd_info = (BackendInfo *)gi;
 655                 }
 656         }
 657         /* If there are any unresolved subordinates left, something is wrong */
 658         return cont;
 659 }