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