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