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 2001-2003 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                 if (dnIsSuffix(&bv, &gi->n[i].be->be_nsuffix[0])) {
  80                         return gi->n[i].be;
  81                 }
  82         }
  83         return NULL;
  84 }
  85
  86 /* This function will only be called in tool mode */
  87 static int
  88 glue_back_open (
  89         BackendInfo *bi
  90 )
  91 {
  92         int rc = 0;
  93         static int glueOpened = 0;
  94
  95         if (glueOpened) return 0;
  96
  97         glueOpened = 1;
  98
  99         /* If we were invoked in tool mode, open all the underlying backends */
 100         if (slapMode & SLAP_TOOL_MODE) {
 101                 rc = backend_startup (NULL);
 102         } /* other case is impossible */
 103         return rc;
 104 }
 105
 106 /* This function will only be called in tool mode */
 107 static int
 108 glue_back_close (
 109         BackendInfo *bi
 110 )
 111 {
 112         static int glueClosed = 0;
 113         int rc = 0;
 114
 115         if (glueClosed) return 0;
 116
 117         glueClosed = 1;
 118
 119         if (slapMode & SLAP_TOOL_MODE) {
 120                 rc = backend_shutdown (NULL);
 121         }
 122         return rc;
 123 }
 124
 125 static int
 126 glue_back_db_open (
 127         BackendDB *be
 128 )
 129 {
 130         glueinfo *gi = (glueinfo *) be->bd_info;
 131         static int glueOpened = 0;
 132         int rc = 0;
 133
 134         if (glueOpened) return 0;
 135
 136         glueOpened = 1;
 137
 138         gi->bd.be_acl = be->be_acl;
 139
 140         if (gi->bd.bd_info->bi_db_open)
 141                 rc = gi->bd.bd_info->bi_db_open(&gi->bd);
 142
 143         return rc;
 144 }
 145
 146 static int
 147 glue_back_db_close (
 148         BackendDB *be
 149 )
 150 {
 151         glueinfo *gi = (glueinfo *) be->bd_info;
 152         static int glueClosed = 0;
 153
 154         if (glueClosed) return 0;
 155
 156         glueClosed = 1;
 157
 158         /* Close the master */
 159         if (gi->bd.bd_info->bi_db_close)
 160                 gi->bd.bd_info->bi_db_close( &gi->bd );
 161
 162         return 0;
 163 }
 164
 165 static int
 166 glue_back_db_destroy (
 167         BackendDB *be
 168 )
 169 {
 170         glueinfo *gi = (glueinfo *) be->bd_info;
 171
 172         if (gi->bd.bd_info->bi_db_destroy)
 173                 gi->bd.bd_info->bi_db_destroy( &gi->bd );
 174         free (gi);
 175         return 0;
 176 }
 177
 178 typedef struct glue_state {
 179         int err;
 180         int is_slimit;
 181         int slimit;
 182         int matchlen;
 183         char *matched;
 184         int nrefs;
 185         BerVarray refs;
 186 } glue_state;
 187
 188 static int
 189 glue_back_response ( Operation *op, SlapReply *rs )
 190 {
 191         glue_state *gs = op->o_callback->sc_private;
 192
 193         switch(rs->sr_type) {
 194         case REP_SEARCH:
 195                 if ( gs->is_slimit && rs->sr_nentries >= gs->slimit ) {
 196                         gs->err = LDAP_SIZELIMIT_EXCEEDED;
 197                         return -1;
 198                 }
 199                 /* fallthru */
 200         case REP_SEARCHREF:
 201                 return SLAP_CB_CONTINUE;
 202
 203         default:
 204                 if ( gs->is_slimit && rs->sr_err == LDAP_SIZELIMIT_EXCEEDED
 205                                 && rs->sr_nentries >= gs->slimit ) {
 206                         gs->err = LDAP_SIZELIMIT_EXCEEDED;
 207                         return -1;
 208                 }
 209                 if (rs->sr_err == LDAP_SUCCESS || gs->err != LDAP_SUCCESS) {
 210                         gs->err = rs->sr_err;
 211                 }
 212                 if (gs->err == LDAP_SUCCESS && gs->matched) {
 213                         ch_free (gs->matched);
 214                         gs->matched = NULL;
 215                         gs->matchlen = 0;
 216                 }
 217                 if (gs->err != LDAP_SUCCESS && rs->sr_matched) {
 218                         int len;
 219                         len = strlen (rs->sr_matched);
 220                         if (len > gs->matchlen) {
 221                                 if (gs->matched)
 222                                         ch_free (gs->matched);
 223                                 gs->matched = ch_strdup (rs->sr_matched);
 224                                 gs->matchlen = len;
 225                         }
 226                 }
 227                 if (rs->sr_ref) {
 228                         int i, j, k;
 229                         BerVarray new;
 230
 231                         for (i=0; rs->sr_ref[i].bv_val; i++);
 232
 233                         j = gs->nrefs;
 234                         if (!j) {
 235                                 new = ch_malloc ((i+1)*sizeof(struct berval));
 236                         } else {
 237                                 new = ch_realloc(gs->refs,
 238                                         (j+i+1)*sizeof(struct berval));
 239                         }
 240                         for (k=0; k<i; j++,k++) {
 241                                 ber_dupbv( &new[j], &rs->sr_ref[k] );
 242                         }
 243                         new[j].bv_val = NULL;
 244                         gs->nrefs = j;
 245                         gs->refs = new;
 246                 }
 247         }
 248         return 0;
 249 }
 250
 251 static int
 252 glue_back_search ( Operation *op, SlapReply *rs )
 253 {
 254         BackendDB *b0 = op->o_bd;
 255         glueinfo *gi = (glueinfo *) b0->bd_info;
 256         int i;
 257         long stoptime = 0;
 258         glue_state gs = {0, 0, 0, 0, NULL, 0, NULL};
 259         slap_callback cb = { NULL, glue_back_response, NULL, NULL };
 260         int scope0, slimit0, tlimit0;
 261         struct berval dn, ndn;
 262
 263         gs.is_slimit = ( op->ors_slimit > 0 );
 264
 265         cb.sc_private = &gs;
 266
 267         cb.sc_next = op->o_callback;
 268
 269         if (op->ors_tlimit) {
 270                 stoptime = slap_get_time () + op->ors_tlimit;
 271         }
 272
 273         switch (op->ors_scope) {
 274         case LDAP_SCOPE_BASE:
 275                 op->o_bd = glue_back_select (b0, op->o_req_ndn.bv_val);
 276
 277                 if (op->o_bd && op->o_bd->be_search) {
 278                         rs->sr_err = op->o_bd->be_search( op, rs );
 279                 } else {
 280                         send_ldap_error(op, rs, LDAP_UNWILLING_TO_PERFORM,
 281                                       "No search target found");
 282                 }
 283                 return rs->sr_err;
 284
 285         case LDAP_SCOPE_ONELEVEL:
 286         case LDAP_SCOPE_SUBTREE:
 287                 op->o_callback = &cb;
 288                 rs->sr_err = gs.err = LDAP_UNWILLING_TO_PERFORM;
 289                 scope0 = op->ors_scope;
 290                 if ( gs.is_slimit ) {
 291                         slimit0 = gs.slimit = op->ors_slimit;
 292                 }
 293                 tlimit0 = op->ors_tlimit;
 294                 dn = op->o_req_dn;
 295                 ndn = op->o_req_ndn;
 296
 297                 /*
 298                  * Execute in reverse order, most general first
 299                  */
 300                 for (i = gi->nodes-1; i >= 0; i--) {
 301                         if (!gi->n[i].be || !gi->n[i].be->be_search)
 302                                 continue;
 303                         if (tlimit0) {
 304                                 op->ors_tlimit = stoptime - slap_get_time ();
 305                                 if (op->ors_tlimit <= 0) {
 306                                         rs->sr_err = gs.err = LDAP_TIMELIMIT_EXCEEDED;
 307                                         break;
 308                                 }
 309                         }
 310                         if ( gs.is_slimit ) {
 311                                 op->ors_slimit = slimit0 - rs->sr_nentries;
 312                                 if (op->ors_slimit < 0) {
 313                                         rs->sr_err = gs.err = LDAP_SIZELIMIT_EXCEEDED;
 314                                         break;
 315                                 }
 316                         }
 317                         rs->sr_err = 0;
 318                         /*
 319                          * check for abandon
 320                          */
 321                         if (op->o_abandon) {
 322                                 goto done;
 323                         }
 324                         op->o_bd = gi->n[i].be;
 325                         if (scope0 == LDAP_SCOPE_ONELEVEL &&
 326                                 dn_match(&gi->n[i].pdn, &ndn)) {
 327                                 op->ors_scope = LDAP_SCOPE_BASE;
 328                                 op->o_req_dn = op->o_bd->be_suffix[0];
 329                                 op->o_req_ndn = op->o_bd->be_nsuffix[0];
 330                                 rs->sr_err = op->o_bd->be_search(op, rs);
 331
 332                         } else if (scope0 == LDAP_SCOPE_SUBTREE &&
 333                                 dnIsSuffix(&op->o_bd->be_nsuffix[0], &ndn)) {
 334                                 op->o_req_dn = op->o_bd->be_suffix[0];
 335                                 op->o_req_ndn = op->o_bd->be_nsuffix[0];
 336                                 rs->sr_err = op->o_bd->be_search( op, rs );
 337
 338                         } else if (dnIsSuffix(&ndn, &op->o_bd->be_nsuffix[0])) {
 339                                 rs->sr_err = op->o_bd->be_search( op, rs );
 340                         }
 341
 342                         switch ( gs.err ) {
 343
 344                         /*
 345                          * Add errors that should result in dropping
 346                          * the search
 347                          */
 348                         case LDAP_SIZELIMIT_EXCEEDED:
 349                         case LDAP_TIMELIMIT_EXCEEDED:
 350                         case LDAP_ADMINLIMIT_EXCEEDED:
 351                                 goto end_of_loop;
 352
 353                         default:
 354                                 break;
 355                         }
 356                 }
 357 end_of_loop:;
 358                 op->ors_scope = scope0;
 359                 if ( gs.is_slimit ) {
 360                         op->ors_slimit = slimit0;
 361                 }
 362                 op->ors_tlimit = tlimit0;
 363                 op->o_req_dn = dn;
 364                 op->o_req_ndn = ndn;
 365
 366                 break;
 367         }
 368         op->o_callback = cb.sc_next;
 369         rs->sr_err = gs.err;
 370         rs->sr_matched = gs.matched;
 371         rs->sr_ref = gs.refs;
 372
 373         send_ldap_result( op, rs );
 374
 375 done:
 376         op->o_bd = b0;
 377         if (gs.matched)
 378                 free (gs.matched);
 379         if (gs.refs)
 380                 ber_bvarray_free(gs.refs);
 381         return rs->sr_err;
 382 }
 383
 384
 385 static int
 386 glue_tool_entry_open (
 387         BackendDB *b0,
 388         int mode
 389 )
 390 {
 391         /* We don't know which backend to talk to yet, so just
 392          * remember the mode and move on...
 393          */
 394
 395         glueMode = mode;
 396         glueBack = NULL;
 397
 398         return 0;
 399 }
 400
 401 static int
 402 glue_tool_entry_close (
 403         BackendDB *b0
 404 )
 405 {
 406         int rc = 0;
 407
 408         if (glueBack) {
 409                 if (!glueBack->be_entry_close)
 410                         return 0;
 411                 rc = glueBack->be_entry_close (glueBack);
 412         }
 413         return rc;
 414 }
 415
 416 static ID
 417 glue_tool_entry_first (
 418         BackendDB *b0
 419 )
 420 {
 421         glueinfo *gi = (glueinfo *) b0->bd_info;
 422         int i;
 423
 424         /* If we're starting from scratch, start at the most general */
 425         if (!glueBack) {
 426                 for (i = gi->nodes-1; i >= 0; i--) {
 427                         if (gi->n[i].be->be_entry_open &&
 428                             gi->n[i].be->be_entry_first) {
 429                                 glueBack = gi->n[i].be;
 430                                 break;
 431                         }
 432                 }
 433
 434         }
 435         if (!glueBack || glueBack->be_entry_open (glueBack, glueMode) != 0)
 436                 return NOID;
 437
 438         return glueBack->be_entry_first (glueBack);
 439 }
 440
 441 static ID
 442 glue_tool_entry_next (
 443         BackendDB *b0
 444 )
 445 {
 446         glueinfo *gi = (glueinfo *) b0->bd_info;
 447         int i;
 448         ID rc;
 449
 450         if (!glueBack || !glueBack->be_entry_next)
 451                 return NOID;
 452
 453         rc = glueBack->be_entry_next (glueBack);
 454
 455         /* If we ran out of entries in one database, move on to the next */
 456         if (rc == NOID) {
 457                 glueBack->be_entry_close (glueBack);
 458                 for (i=0; i<gi->nodes; i++) {
 459                         if (gi->n[i].be == glueBack)
 460                                 break;
 461                 }
 462                 if (i == 0) {
 463                         glueBack = NULL;
 464                         rc = NOID;
 465                 } else {
 466                         glueBack = gi->n[i-1].be;
 467                         rc = glue_tool_entry_first (b0);
 468                 }
 469         }
 470         return rc;
 471 }
 472
 473 static Entry *
 474 glue_tool_entry_get (
 475         BackendDB *b0,
 476         ID id
 477 )
 478 {
 479         if (!glueBack || !glueBack->be_entry_get)
 480                 return NULL;
 481
 482         return glueBack->be_entry_get (glueBack, id);
 483 }
 484
 485 static ID
 486 glue_tool_entry_put (
 487         BackendDB *b0,
 488         Entry *e,
 489         struct berval *text
 490 )
 491 {
 492         BackendDB *be;
 493         int rc;
 494
 495         be = glue_back_select (b0, e->e_ndn);
 496         if (!be->be_entry_put)
 497                 return NOID;
 498
 499         if (!glueBack) {
 500                 rc = be->be_entry_open (be, glueMode);
 501                 if (rc != 0)
 502                         return NOID;
 503         } else if (be != glueBack) {
 504                 /* If this entry belongs in a different branch than the
 505                  * previous one, close the current database and open the
 506                  * new one.
 507                  */
 508                 glueBack->be_entry_close (glueBack);
 509                 rc = be->be_entry_open (be, glueMode);
 510                 if (rc != 0)
 511                         return NOID;
 512         }
 513         glueBack = be;
 514         return be->be_entry_put (be, e, text);
 515 }
 516
 517 static int
 518 glue_tool_entry_reindex (
 519         BackendDB *b0,
 520         ID id
 521 )
 522 {
 523         if (!glueBack || !glueBack->be_entry_reindex)
 524                 return -1;
 525
 526         return glueBack->be_entry_reindex (glueBack, id);
 527 }
 528
 529 static int
 530 glue_tool_sync (
 531         BackendDB *b0
 532 )
 533 {
 534         glueinfo *gi = (glueinfo *) b0->bd_info;
 535         int i;
 536
 537         /* just sync everyone */
 538         for (i = 0; i<gi->nodes; i++)
 539                 if (gi->n[i].be->be_sync)
 540                         gi->n[i].be->be_sync (gi->n[i].be);
 541         return 0;
 542 }
 543
 544 int
 545 glue_sub_init( )
 546 {
 547         int i, j;
 548         int cont = num_subordinates;
 549         BackendDB *b1, *be;
 550         BackendInfo *bi = NULL;
 551         glueinfo *gi;
 552
 553         /* While there are subordinate backends, search backwards through the
 554          * backends and connect them to their superior.
 555          */
 556         for (i = nBackendDB - 1, b1=&backendDB[i]; cont && i>=0; b1--,i--) {
 557                 if (SLAP_GLUE_SUBORDINATE ( b1 ) ) {
 558                         /* The last database cannot be a subordinate of noone */
 559                         if (i == nBackendDB - 1) {
 560                                 b1->be_flags ^= SLAP_BFLAG_GLUE_SUBORDINATE;
 561                         }
 562                         continue;
 563                 }
 564                 gi = NULL;
 565                 for (j = i-1, be=&backendDB[j]; j>=0; be--,j--) {
 566                         if ( ! SLAP_GLUE_SUBORDINATE( be ) ) {
 567                                 continue;
 568                         }
 569                         /* We will only link it once */
 570                         if ( SLAP_GLUE_LINKED( be ) ) {
 571                                 continue;
 572                         }
 573                         if (!dnIsSuffix(&be->be_nsuffix[0], &b1->be_nsuffix[0])) {
 574                                 continue;
 575                         }
 576                         cont--;
 577                         be->be_flags |= SLAP_BFLAG_GLUE_LINKED;
 578                         if (gi == NULL) {
 579                                 /* We create a copy of the superior's be
 580                                  * structure, pointing to all of its original
 581                                  * information. Then we replace elements of
 582                                  * the superior's info with our own. The copy
 583                                  * is used whenever we have operations to pass
 584                                  * down to the real database.
 585                                  */
 586                                 b1->be_flags |= SLAP_BFLAG_GLUE_INSTANCE;
 587                                 gi = (glueinfo *)ch_malloc(sizeof(glueinfo));
 588                                 gi->nodes = 0;
 589                                 gi->bd = *b1;
 590                                 gi->bi = *b1->bd_info;
 591                                 bi = (BackendInfo *)gi;
 592                                 bi->bi_open = glue_back_open;
 593                                 bi->bi_close = glue_back_close;
 594                                 bi->bi_db_open = glue_back_db_open;
 595                                 bi->bi_db_close = glue_back_db_close;
 596                                 bi->bi_db_destroy = glue_back_db_destroy;
 597
 598                                 bi->bi_op_search = glue_back_search;
 599
 600                                 /*
 601                                  * hooks for slap tools
 602                                  */
 603                                 bi->bi_tool_entry_open = glue_tool_entry_open;
 604                                 bi->bi_tool_entry_close = glue_tool_entry_close;
 605                                 bi->bi_tool_entry_first = glue_tool_entry_first;
 606                                 bi->bi_tool_entry_next = glue_tool_entry_next;
 607                                 bi->bi_tool_entry_get = glue_tool_entry_get;
 608                                 bi->bi_tool_entry_put = glue_tool_entry_put;
 609                                 bi->bi_tool_entry_reindex = glue_tool_entry_reindex;
 610                                 bi->bi_tool_sync = glue_tool_sync;
 611                                 /* FIXME : will support later */
 612                                 bi->bi_tool_dn2id_get = 0;
 613                                 bi->bi_tool_id2entry_get = 0;
 614                                 bi->bi_tool_entry_modify = 0;
 615                         } else {
 616                                 gi = (glueinfo *)ch_realloc(gi,
 617                                         sizeof(glueinfo) +
 618                                         gi->nodes * sizeof(gluenode));
 619                         }
 620                         gi->n[gi->nodes].be = be;
 621                         dnParent( &be->be_nsuffix[0], &gi->n[gi->nodes].pdn );
 622                         gi->nodes++;
 623                 }
 624                 if (gi) {
 625                         /* One more node for the master */
 626                         gi = (glueinfo *)ch_realloc(gi,
 627                                 sizeof(glueinfo) + gi->nodes * sizeof(gluenode));
 628                         gi->n[gi->nodes].be = &gi->bd;
 629                         dnParent( &b1->be_nsuffix[0], &gi->n[gi->nodes].pdn );
 630                         gi->nodes++;
 631                         b1->bd_info = (BackendInfo *)gi;
 632                 }
 633         }
 634         /* If there are any unresolved subordinates left, something is wrong */
 635         return cont;
 636 }