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

   1 /* backglue.c - backend glue routines */
   2 /* $OpenLDAP$ */
   3 /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
   4  *
   5  * Copyright 2001-2004 The OpenLDAP Foundation.
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted only as authorized by the OpenLDAP
  10  * Public License.
  11  *
  12  * A copy of this license is available in the file LICENSE in the
  13  * top-level directory of the distribution or, alternatively, at
  14  * <http://www.OpenLDAP.org/license.html>.
  15  */
  16
  17 /*
  18  * Functions to glue a bunch of other backends into a single tree.
  19  * All of the glued backends must share a common suffix. E.g., you
  20  * can glue o=foo and ou=bar,o=foo but you can't glue o=foo and o=bar.
  21  *
  22  * This uses the backend structures and routines extensively, but is
  23  * not an actual backend of its own. To use it you must add a "subordinate"
  24  * keyword to the configuration of other backends. Subordinates will
  25  * automatically be connected to their parent backend.
  26  *
  27  * The purpose of these functions is to allow you to split a single database
  28  * into pieces (for load balancing purposes, whatever) but still be able
  29  * to treat it as a single database after it's been split. As such, each
  30  * of the glued backends should have identical rootdn and rootpw.
  31  *
  32  * If you need more elaborate configuration, you probably should be using
  33  * back-meta instead.
  34  *  -- Howard Chu
  35  */
  36
  37 #include "portable.h"
  38
  39 #include <stdio.h>
  40
  41 #include <ac/string.h>
  42 #include <ac/socket.h>
  43
  44 #define SLAPD_TOOLS
  45 #include "slap.h"
  46
  47 typedef struct gluenode {
  48         BackendDB *be;
  49         struct berval pdn;
  50 } gluenode;
  51
  52 typedef struct glueinfo {
  53         BackendInfo bi;
  54         BackendDB bd;
  55         int nodes;
  56         gluenode n[1];
  57 } glueinfo;
  58
  59 static int glueMode;
  60 static BackendDB *glueBack;
  61
  62 static slap_response glue_back_response;
  63
  64 /* Just like select_backend, but only for our backends */
  65 static BackendDB *
  66 glue_back_select (
  67         BackendDB *be,
  68         const char *dn
  69 )
  70 {
  71         glueinfo *gi = (glueinfo *) be->bd_info;
  72         struct berval bv;
  73         int i;
  74
  75         bv.bv_len = strlen(dn);
  76         bv.bv_val = (char *) dn;
  77
  78         for (i = 0; i<gi->nodes; i++) {
  79                 assert( gi->n[i].be->be_nsuffix );
  80
  81                 if (dnIsSuffix(&bv, &gi->n[i].be->be_nsuffix[0])) {
  82                         return gi->n[i].be;
  83                 }
  84         }
  85         return NULL;
  86 }
  87
  88 /* This function will only be called in tool mode */
  89 static int
  90 glue_back_open (
  91         BackendInfo *bi
  92 )
  93 {
  94         int rc = 0;
  95         static int glueOpened = 0;
  96
  97         if (glueOpened) return 0;
  98
  99         glueOpened = 1;
 100
 101         /* If we were invoked in tool mode, open all the underlying backends */
 102         if (slapMode & SLAP_TOOL_MODE) {
 103                 rc = backend_startup (NULL);
 104         } /* other case is impossible */
 105         return rc;
 106 }
 107
 108 /* This function will only be called in tool mode */
 109 static int
 110 glue_back_close (
 111         BackendInfo *bi
 112 )
 113 {
 114         static int glueClosed = 0;
 115         int rc = 0;
 116
 117         if (glueClosed) return 0;
 118
 119         glueClosed = 1;
 120
 121         if (slapMode & SLAP_TOOL_MODE) {
 122                 rc = backend_shutdown (NULL);
 123         }
 124         return rc;
 125 }
 126
 127 static int
 128 glue_back_db_open (
 129         BackendDB *be
 130 )
 131 {
 132         glueinfo *gi = (glueinfo *) be->bd_info;
 133         static int glueOpened = 0;
 134         int rc = 0;
 135
 136         if (glueOpened) return 0;
 137
 138         glueOpened = 1;
 139
 140         gi->bd.be_acl = be->be_acl;
 141
 142         if (gi->bd.bd_info->bi_db_open)
 143                 rc = gi->bd.bd_info->bi_db_open(&gi->bd);
 144
 145         return rc;
 146 }
 147
 148 static int
 149 glue_back_db_close (
 150         BackendDB *be
 151 )
 152 {
 153         glueinfo *gi = (glueinfo *) be->bd_info;
 154         static int glueClosed = 0;
 155
 156         if (glueClosed) return 0;
 157
 158         glueClosed = 1;
 159
 160         /* Close the master */
 161         if (gi->bd.bd_info->bi_db_close)
 162                 gi->bd.bd_info->bi_db_close( &gi->bd );
 163
 164         return 0;
 165 }
 166
 167 static int
 168 glue_back_db_destroy (
 169         BackendDB *be
 170 )
 171 {
 172         glueinfo *gi = (glueinfo *) be->bd_info;
 173
 174         if (gi->bd.bd_info->bi_db_destroy)
 175                 gi->bd.bd_info->bi_db_destroy( &gi->bd );
 176         free (gi);
 177         return 0;
 178 }
 179
 180 typedef struct glue_state {
 181         int err;
 182         int slimit;
 183         int matchlen;
 184         char *matched;
 185         int nrefs;
 186         BerVarray refs;
 187 } glue_state;
 188
 189 static int
 190 glue_back_response ( Operation *op, SlapReply *rs )
 191 {
 192         glue_state *gs = op->o_callback->sc_private;
 193
 194         switch(rs->sr_type) {
 195         case REP_SEARCH:
 196                 if ( gs->slimit && rs->sr_nentries >= gs->slimit ) {
 197                         gs->err = LDAP_SIZELIMIT_EXCEEDED;
 198                         return -1;
 199                 }
 200                 /* fallthru */
 201         case REP_SEARCHREF:
 202                 return SLAP_CB_CONTINUE;
 203
 204         default:
 205                 if (rs->sr_err == LDAP_SUCCESS ||
 206                         rs->sr_err == LDAP_SIZELIMIT_EXCEEDED ||
 207                         rs->sr_err == LDAP_TIMELIMIT_EXCEEDED ||
 208                         rs->sr_err == LDAP_ADMINLIMIT_EXCEEDED ||
 209                                 gs->err != LDAP_SUCCESS)
 210                         gs->err = rs->sr_err;
 211                 if (gs->err == LDAP_SUCCESS && gs->matched) {
 212                         ch_free (gs->matched);
 213                         gs->matched = NULL;
 214                         gs->matchlen = 0;
 215                 }
 216                 if (gs->err != LDAP_SUCCESS && rs->sr_matched) {
 217                         int len;
 218                         len = strlen (rs->sr_matched);
 219                         if (len > gs->matchlen) {
 220                                 if (gs->matched)
 221                                         ch_free (gs->matched);
 222                                 gs->matched = ch_strdup (rs->sr_matched);
 223                                 gs->matchlen = len;
 224                         }
 225                 }
 226                 if (rs->sr_ref) {
 227                         int i, j, k;
 228                         BerVarray new;
 229
 230                         for (i=0; rs->sr_ref[i].bv_val; i++);
 231
 232                         j = gs->nrefs;
 233                         if (!j) {
 234                                 new = ch_malloc ((i+1)*sizeof(struct berval));
 235                         } else {
 236                                 new = ch_realloc(gs->refs,
 237                                         (j+i+1)*sizeof(struct berval));
 238                         }
 239                         for (k=0; k<i; j++,k++) {
 240                                 ber_dupbv( &new[j], &rs->sr_ref[k] );
 241                         }
 242                         new[j].bv_val = NULL;
 243                         gs->nrefs = j;
 244                         gs->refs = new;
 245                 }
 246         }
 247         return 0;
 248 }
 249
 250 static int
 251 glue_back_search ( Operation *op, SlapReply *rs )
 252 {
 253         BackendDB *b0 = op->o_bd;
 254         glueinfo *gi = (glueinfo *) b0->bd_info;
 255         int i;
 256         long stoptime = 0;
 257         glue_state gs = {0, 0, 0, NULL, 0, NULL};
 258         slap_callback cb = { NULL, glue_back_response, NULL, NULL };
 259         int scope0, slimit0, tlimit0;
 260         struct berval dn, ndn;
 261
 262         cb.sc_private = &gs;
 263
 264         cb.sc_next = op->o_callback;
 265
 266         if (op->ors_tlimit) {
 267                 stoptime = slap_get_time () + op->ors_tlimit;
 268         }
 269
 270         switch (op->ors_scope) {
 271         case LDAP_SCOPE_BASE:
 272                 op->o_bd = glue_back_select (b0, op->o_req_ndn.bv_val);
 273
 274                 if (op->o_bd && op->o_bd->be_search) {
 275                         rs->sr_err = op->o_bd->be_search( op, rs );
 276                 } else {
 277                         send_ldap_error(op, rs, LDAP_UNWILLING_TO_PERFORM,
 278                                       "No search target found");
 279                 }
 280                 return rs->sr_err;
 281
 282         case LDAP_SCOPE_ONELEVEL:
 283         case LDAP_SCOPE_SUBTREE:
 284         case LDAP_SCOPE_SUBORDINATE: /* FIXME */
 285                 op->o_callback = &cb;
 286                 rs->sr_err = gs.err = LDAP_UNWILLING_TO_PERFORM;
 287                 scope0 = op->ors_scope;
 288                 slimit0 = gs.slimit = op->ors_slimit;
 289                 tlimit0 = op->ors_tlimit;
 290                 dn = op->o_req_dn;
 291                 ndn = op->o_req_ndn;
 292
 293                 /*
 294                  * Execute in reverse order, most general first
 295                  */
 296                 for (i = gi->nodes-1; i >= 0; i--) {
 297                         if (!gi->n[i].be || !gi->n[i].be->be_search)
 298                                 continue;
 299                         if (tlimit0) {
 300                                 op->ors_tlimit = stoptime - slap_get_time ();
 301                                 if (op->ors_tlimit <= 0) {
 302                                         rs->sr_err = gs.err = LDAP_TIMELIMIT_EXCEEDED;
 303                                         break;
 304                                 }
 305                         }
 306                         if (slimit0) {
 307                                 op->ors_slimit = slimit0 - rs->sr_nentries;
 308                                 if (op->ors_slimit < 0) {
 309                                         rs->sr_err = gs.err = LDAP_SIZELIMIT_EXCEEDED;
 310                                         break;
 311                                 }
 312                         }
 313                         rs->sr_err = 0;
 314                         /*
 315                          * check for abandon
 316                          */
 317                         if (op->o_abandon) {
 318                                 goto done;
 319                         }
 320                         op->o_bd = gi->n[i].be;
 321
 322                         assert( op->o_bd->be_suffix );
 323                         assert( op->o_bd->be_nsuffix );
 324
 325                         if (scope0 == LDAP_SCOPE_ONELEVEL &&
 326                                 dn_match(&gi->n[i].pdn, &ndn))
 327                         {
 328                                 op->ors_scope = LDAP_SCOPE_BASE;
 329                                 op->o_req_dn = op->o_bd->be_suffix[0];
 330                                 op->o_req_ndn = op->o_bd->be_nsuffix[0];
 331                                 rs->sr_err = op->o_bd->be_search(op, rs);
 332
 333                         } else if (scope0 == LDAP_SCOPE_SUBTREE &&
 334                                 dnIsSuffix(&op->o_bd->be_nsuffix[0], &ndn))
 335                         {
 336                                 op->o_req_dn = op->o_bd->be_suffix[0];
 337                                 op->o_req_ndn = op->o_bd->be_nsuffix[0];
 338                                 rs->sr_err = op->o_bd->be_search( op, rs );
 339
 340                         } else if (dnIsSuffix(&ndn, &op->o_bd->be_nsuffix[0])) {
 341                                 rs->sr_err = op->o_bd->be_search( op, rs );
 342                         }
 343
 344                         switch ( gs.err ) {
 345
 346                         /*
 347                          * Add errors that should result in dropping
 348                          * the search
 349                          */
 350                         case LDAP_SIZELIMIT_EXCEEDED:
 351                         case LDAP_TIMELIMIT_EXCEEDED:
 352                         case LDAP_ADMINLIMIT_EXCEEDED:
 353                                 goto end_of_loop;
 354
 355                         default:
 356                                 break;
 357                         }
 358                 }
 359 end_of_loop:;
 360                 op->ors_scope = scope0;
 361                 op->ors_slimit = slimit0;
 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->be_entry_first ||
 436                 glueBack->be_entry_open (glueBack, glueMode) != 0)
 437                 return NOID;
 438
 439         return glueBack->be_entry_first (glueBack);
 440 }
 441
 442 static ID
 443 glue_tool_entry_next (
 444         BackendDB *b0
 445 )
 446 {
 447         glueinfo *gi = (glueinfo *) b0->bd_info;
 448         int i;
 449         ID rc;
 450
 451         if (!glueBack || !glueBack->be_entry_next)
 452                 return NOID;
 453
 454         rc = glueBack->be_entry_next (glueBack);
 455
 456         /* If we ran out of entries in one database, move on to the next */
 457         while (rc == NOID) {
 458                 if ( glueBack && glueBack->be_entry_close )
 459                         glueBack->be_entry_close (glueBack);
 460                 for (i=0; i<gi->nodes; i++) {
 461                         if (gi->n[i].be == glueBack)
 462                                 break;
 463                 }
 464                 if (i == 0) {
 465                         glueBack = NULL;
 466                         break;
 467                 } else {
 468                         glueBack = gi->n[i-1].be;
 469                         rc = glue_tool_entry_first (b0);
 470                 }
 471         }
 472         return rc;
 473 }
 474
 475 static Entry *
 476 glue_tool_entry_get (
 477         BackendDB *b0,
 478         ID id
 479 )
 480 {
 481         if (!glueBack || !glueBack->be_entry_get)
 482                 return NULL;
 483
 484         return glueBack->be_entry_get (glueBack, id);
 485 }
 486
 487 static ID
 488 glue_tool_entry_put (
 489         BackendDB *b0,
 490         Entry *e,
 491         struct berval *text
 492 )
 493 {
 494         BackendDB *be;
 495         int rc;
 496
 497         be = glue_back_select (b0, e->e_ndn);
 498         if (!be->be_entry_put)
 499                 return NOID;
 500
 501         if (!glueBack) {
 502                 rc = be->be_entry_open (be, glueMode);
 503                 if (rc != 0)
 504                         return NOID;
 505         } else if (be != glueBack) {
 506                 /* If this entry belongs in a different branch than the
 507                  * previous one, close the current database and open the
 508                  * new one.
 509                  */
 510                 glueBack->be_entry_close (glueBack);
 511                 rc = be->be_entry_open (be, glueMode);
 512                 if (rc != 0)
 513                         return NOID;
 514         }
 515         glueBack = be;
 516         return be->be_entry_put (be, e, text);
 517 }
 518
 519 static int
 520 glue_tool_entry_reindex (
 521         BackendDB *b0,
 522         ID id
 523 )
 524 {
 525         if (!glueBack || !glueBack->be_entry_reindex)
 526                 return -1;
 527
 528         return glueBack->be_entry_reindex (glueBack, id);
 529 }
 530
 531 static int
 532 glue_tool_sync (
 533         BackendDB *b0
 534 )
 535 {
 536         glueinfo *gi = (glueinfo *) b0->bd_info;
 537         int i;
 538
 539         /* just sync everyone */
 540         for (i = 0; i<gi->nodes; i++)
 541                 if (gi->n[i].be->be_sync)
 542                         gi->n[i].be->be_sync (gi->n[i].be);
 543         return 0;
 544 }
 545
 546 int
 547 glue_sub_init( )
 548 {
 549         int i, j;
 550         int cont = num_subordinates;
 551         BackendDB *b1, *be;
 552         BackendInfo *bi = NULL;
 553         glueinfo *gi;
 554
 555         /* While there are subordinate backends, search backwards through the
 556          * backends and connect them to their superior.
 557          */
 558         for (i = nBackendDB - 1, b1=&backendDB[i]; cont && i>=0; b1--,i--) {
 559                 if (SLAP_GLUE_SUBORDINATE ( b1 ) ) {
 560                         /* The last database cannot be a subordinate of noone */
 561                         if (i == nBackendDB - 1) {
 562                                 b1->be_flags ^= SLAP_BFLAG_GLUE_SUBORDINATE;
 563                         }
 564                         continue;
 565                 }
 566                 gi = NULL;
 567                 for (j = i-1, be=&backendDB[j]; j>=0; be--,j--) {
 568                         if ( ! SLAP_GLUE_SUBORDINATE( be ) ) {
 569                                 continue;
 570                         }
 571                         /* We will only link it once */
 572                         if ( SLAP_GLUE_LINKED( be ) ) {
 573                                 continue;
 574                         }
 575                         assert( be->be_nsuffix );
 576                         assert( b1->be_nsuffix );
 577                         if (!dnIsSuffix(&be->be_nsuffix[0], &b1->be_nsuffix[0])) {
 578                                 continue;
 579                         }
 580                         cont--;
 581                         be->be_flags |= SLAP_BFLAG_GLUE_LINKED;
 582                         if (gi == NULL) {
 583                                 /* We create a copy of the superior's be
 584                                  * structure, pointing to all of its original
 585                                  * information. Then we replace elements of
 586                                  * the superior's info with our own. The copy
 587                                  * is used whenever we have operations to pass
 588                                  * down to the real database.
 589                                  */
 590                                 b1->be_flags |= SLAP_BFLAG_GLUE_INSTANCE;
 591                                 gi = (glueinfo *)ch_malloc(sizeof(glueinfo));
 592                                 gi->nodes = 0;
 593                                 gi->bd = *b1;
 594                                 gi->bi = *b1->bd_info;
 595                                 bi = (BackendInfo *)gi;
 596                                 bi->bi_open = glue_back_open;
 597                                 bi->bi_close = glue_back_close;
 598                                 bi->bi_db_open = glue_back_db_open;
 599                                 bi->bi_db_close = glue_back_db_close;
 600                                 bi->bi_db_destroy = glue_back_db_destroy;
 601
 602                                 bi->bi_op_search = glue_back_search;
 603
 604                                 /*
 605                                  * hooks for slap tools
 606                                  */
 607                                 bi->bi_tool_entry_open = glue_tool_entry_open;
 608                                 bi->bi_tool_entry_close = glue_tool_entry_close;
 609                                 bi->bi_tool_entry_first = glue_tool_entry_first;
 610                                 bi->bi_tool_entry_next = glue_tool_entry_next;
 611                                 bi->bi_tool_entry_get = glue_tool_entry_get;
 612                                 bi->bi_tool_entry_put = glue_tool_entry_put;
 613                                 bi->bi_tool_entry_reindex = glue_tool_entry_reindex;
 614                                 bi->bi_tool_sync = glue_tool_sync;
 615                                 /* FIXME : will support later */
 616                                 bi->bi_tool_dn2id_get = 0;
 617                                 bi->bi_tool_id2entry_get = 0;
 618                                 bi->bi_tool_entry_modify = 0;
 619                         } else {
 620                                 gi = (glueinfo *)ch_realloc(gi,
 621                                         sizeof(glueinfo) +
 622                                         gi->nodes * sizeof(gluenode));
 623                         }
 624                         gi->n[gi->nodes].be = be;
 625                         dnParent( &be->be_nsuffix[0], &gi->n[gi->nodes].pdn );
 626                         gi->nodes++;
 627                 }
 628                 if (gi) {
 629                         /* One more node for the master */
 630                         gi = (glueinfo *)ch_realloc(gi,
 631                                 sizeof(glueinfo) + gi->nodes * sizeof(gluenode));
 632                         gi->n[gi->nodes].be = &gi->bd;
 633                         dnParent( &b1->be_nsuffix[0], &gi->n[gi->nodes].pdn );
 634                         gi->nodes++;
 635                         b1->bd_info = (BackendInfo *)gi;
 636                 }
 637         }
 638         /* If there are any unresolved subordinates left, something is wrong */
 639         return cont;
 640 }