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

   1 /* backglue.c - backend glue routines */
   2 /* $OpenLDAP$ */
   3 /*
   4  * Copyright 2001-2003 The OpenLDAP Foundation, All Rights Reserved.
   5  * COPYING RESTRICTIONS APPLY, see COPYRIGHT file
   6  */
   7
   8 /*
   9  * Functions to glue a bunch of other backends into a single tree.
  10  * All of the glued backends must share a common suffix. E.g., you
  11  * can glue o=foo and ou=bar,o=foo but you can't glue o=foo and o=bar.
  12  *
  13  * This uses the backend structures and routines extensively, but is
  14  * not an actual backend of its own. To use it you must add a "subordinate"
  15  * keyword to the configuration of other backends. Subordinates will
  16  * automatically be connected to their parent backend.
  17  *
  18  * The purpose of these functions is to allow you to split a single database
  19  * into pieces (for load balancing purposes, whatever) but still be able
  20  * to treat it as a single database after it's been split. As such, each
  21  * of the glued backends should have identical rootdn and rootpw.
  22  *
  23  * If you need more elaborate configuration, you probably should be using
  24  * back-meta instead.
  25  *  -- Howard Chu
  26  */
  27
  28 #include "portable.h"
  29
  30 #include <stdio.h>
  31
  32 #include <ac/string.h>
  33 #include <ac/socket.h>
  34
  35 #define SLAPD_TOOLS
  36 #include "slap.h"
  37
  38 typedef struct gluenode {
  39         BackendDB *be;
  40         struct berval pdn;
  41 } gluenode;
  42
  43 typedef struct glueinfo {
  44         BackendInfo bi;
  45         BackendDB bd;
  46         int nodes;
  47         gluenode n[1];
  48 } glueinfo;
  49
  50 static int glueMode;
  51 static BackendDB *glueBack;
  52
  53 static slap_response glue_back_response;
  54 static slap_sresult glue_back_sresult;
  55 static slap_sendentry glue_back_sendentry;
  56 static slap_sendreference glue_back_sendreference;
  57
  58 /* Just like select_backend, but only for our backends */
  59 static BackendDB *
  60 glue_back_select (
  61         BackendDB *be,
  62         const char *dn
  63 )
  64 {
  65         glueinfo *gi = (glueinfo *) be->bd_info;
  66         struct berval bv;
  67         int i;
  68
  69         bv.bv_len = strlen(dn);
  70         bv.bv_val = (char *) dn;
  71
  72         for (i = 0; i<gi->nodes; i++) {
  73                 if (dnIsSuffix(&bv, &gi->n[i].be->be_nsuffix[0])) {
  74                         return gi->n[i].be;
  75                 }
  76         }
  77         return NULL;
  78 }
  79
  80 /* This function will only be called in tool mode */
  81 static int
  82 glue_back_open (
  83         BackendInfo *bi
  84 )
  85 {
  86         int rc = 0;
  87         static int glueOpened = 0;
  88
  89         if (glueOpened) return 0;
  90
  91         glueOpened = 1;
  92
  93         /* If we were invoked in tool mode, open all the underlying backends */
  94         if (slapMode & SLAP_TOOL_MODE) {
  95                 rc = backend_startup (NULL);
  96         } /* other case is impossible */
  97         return rc;
  98 }
  99
 100 /* This function will only be called in tool mode */
 101 static int
 102 glue_back_close (
 103         BackendInfo *bi
 104 )
 105 {
 106         static int glueClosed = 0;
 107         int rc = 0;
 108
 109         if (glueClosed) return 0;
 110
 111         glueClosed = 1;
 112
 113         if (slapMode & SLAP_TOOL_MODE) {
 114                 rc = backend_shutdown (NULL);
 115         }
 116         return rc;
 117 }
 118
 119 static int
 120 glue_back_db_open (
 121         BackendDB *be
 122 )
 123 {
 124         glueinfo *gi = (glueinfo *) be->bd_info;
 125         static int glueOpened = 0;
 126         int rc = 0;
 127
 128         if (glueOpened) return 0;
 129
 130         glueOpened = 1;
 131
 132         gi->bd.be_acl = be->be_acl;
 133
 134         if (gi->bd.bd_info->bi_db_open)
 135                 rc = gi->bd.bd_info->bi_db_open(&gi->bd);
 136
 137         return rc;
 138 }
 139
 140 static int
 141 glue_back_db_close (
 142         BackendDB *be
 143 )
 144 {
 145         glueinfo *gi = (glueinfo *) be->bd_info;
 146         static int glueClosed = 0;
 147
 148         if (glueClosed) return 0;
 149
 150         glueClosed = 1;
 151
 152         /* Close the master */
 153         if (gi->bd.bd_info->bi_db_close)
 154                 gi->bd.bd_info->bi_db_close( &gi->bd );
 155
 156         return 0;
 157 }
 158
 159 static int
 160 glue_back_db_destroy (
 161         BackendDB *be
 162 )
 163 {
 164         glueinfo *gi = (glueinfo *) be->bd_info;
 165
 166         if (gi->bd.bd_info->bi_db_destroy)
 167                 gi->bd.bd_info->bi_db_destroy( &gi->bd );
 168         free (gi);
 169         return 0;
 170 }
 171
 172 typedef struct glue_state {
 173         int err;
 174         int nentries;
 175         int matchlen;
 176         char *matched;
 177         int nrefs;
 178         BerVarray refs;
 179         slap_callback *prevcb;
 180 } glue_state;
 181
 182 static void
 183 glue_back_response ( Operation *op, SlapReply *rs )
 184 {
 185         glue_state *gs = op->o_callback->sc_private;
 186
 187         if (rs->sr_err == LDAP_SUCCESS || gs->err != LDAP_SUCCESS)
 188                 gs->err = rs->sr_err;
 189         if (gs->err == LDAP_SUCCESS && gs->matched) {
 190                 ch_free (gs->matched);
 191                 gs->matched = NULL;
 192                 gs->matchlen = 0;
 193         }
 194         if (gs->err != LDAP_SUCCESS && rs->sr_matched) {
 195                 int len;
 196                 len = strlen (rs->sr_matched);
 197                 if (len > gs->matchlen) {
 198                         if (gs->matched)
 199                                 ch_free (gs->matched);
 200                         gs->matched = ch_strdup (rs->sr_matched);
 201                         gs->matchlen = len;
 202                 }
 203         }
 204         if (rs->sr_ref) {
 205                 int i, j, k;
 206                 BerVarray new;
 207
 208                 for (i=0; rs->sr_ref[i].bv_val; i++);
 209
 210                 j = gs->nrefs;
 211                 if (!j) {
 212                         new = ch_malloc ((i+1)*sizeof(struct berval));
 213                 } else {
 214                         new = ch_realloc(gs->refs,
 215                                 (j+i+1)*sizeof(struct berval));
 216                 }
 217                 for (k=0; k<i; j++,k++) {
 218                         ber_dupbv( &new[j], &rs->sr_ref[k] );
 219                 }
 220                 new[j].bv_val = NULL;
 221                 gs->nrefs = j;
 222                 gs->refs = new;
 223         }
 224 }
 225
 226 static void
 227 glue_back_sresult ( Operation *op, SlapReply *rs )
 228 {
 229         glue_state *gs = op->o_callback->sc_private;
 230
 231         gs->nentries += rs->sr_nentries;
 232         glue_back_response( op, rs );
 233 }
 234
 235 static int
 236 glue_back_sendentry ( Operation *op, SlapReply *rs )
 237 {
 238         slap_callback *tmp = op->o_callback;
 239         glue_state *gs = tmp->sc_private;
 240
 241         op->o_callback = gs->prevcb;
 242         if (op->o_callback && op->o_callback->sc_sendentry) {
 243                 rs->sr_err = op->o_callback->sc_sendentry(op, rs);
 244         } else {
 245                 rs->sr_err = send_search_entry(op, rs);
 246         }
 247         op->o_callback = tmp;
 248         return rs->sr_err;
 249 }
 250
 251 static int
 252 glue_back_sendreference ( Operation *op, SlapReply *rs )
 253 {
 254         slap_callback *tmp = op->o_callback;
 255         glue_state *gs = tmp->sc_private;
 256
 257         op->o_callback = gs->prevcb;
 258         if (op->o_callback && op->o_callback->sc_sendreference) {
 259                 rs->sr_err = op->o_callback->sc_sendreference( op, rs );
 260         } else {
 261                 rs->sr_err = send_search_reference( op, rs );
 262         }
 263         op->o_callback = tmp;
 264         return rs->sr_err;
 265 }
 266
 267 static int
 268 glue_back_search ( Operation *op, SlapReply *rs )
 269 {
 270         BackendDB *b0 = op->o_bd;
 271         glueinfo *gi = (glueinfo *) b0->bd_info;
 272         int i;
 273         long stoptime = 0;
 274         glue_state gs = {0, 0, 0, NULL, 0, NULL, NULL};
 275         slap_callback cb;
 276         int scope0, slimit0, tlimit0;
 277         struct berval dn, ndn;
 278
 279         cb.sc_response = glue_back_response;
 280         cb.sc_sresult = glue_back_sresult;
 281         cb.sc_sendentry = glue_back_sendentry;
 282         cb.sc_sendreference = glue_back_sendreference;
 283         cb.sc_private = &gs;
 284
 285         gs.prevcb = op->o_callback;
 286
 287         if (op->ors_tlimit) {
 288                 stoptime = slap_get_time () + op->ors_tlimit;
 289         }
 290
 291         switch (op->ors_scope) {
 292         case LDAP_SCOPE_BASE:
 293                 op->o_bd = glue_back_select (b0, op->o_req_ndn.bv_val);
 294
 295                 if (op->o_bd && op->o_bd->be_search) {
 296                         rs->sr_err = op->o_bd->be_search( op, rs );
 297                 } else {
 298                         send_ldap_error(op, rs, LDAP_UNWILLING_TO_PERFORM,
 299                                       "No search target found");
 300                 }
 301                 return rs->sr_err;
 302
 303         case LDAP_SCOPE_ONELEVEL:
 304         case LDAP_SCOPE_SUBTREE:
 305                 op->o_callback = &cb;
 306                 rs->sr_err = gs.err = LDAP_UNWILLING_TO_PERFORM;
 307                 scope0 = op->ors_scope;
 308                 slimit0 = op->ors_slimit;
 309                 tlimit0 = op->ors_tlimit;
 310                 dn = op->o_req_dn;
 311                 ndn = op->o_req_ndn;
 312
 313                 /*
 314                  * Execute in reverse order, most general first
 315                  */
 316                 for (i = gi->nodes-1; i >= 0; i--) {
 317                         if (!gi->n[i].be || !gi->n[i].be->be_search)
 318                                 continue;
 319                         if (tlimit0) {
 320                                 op->ors_tlimit = stoptime - slap_get_time ();
 321                                 if (op->ors_tlimit <= 0) {
 322                                         rs->sr_err = gs.err = LDAP_TIMELIMIT_EXCEEDED;
 323                                         break;
 324                                 }
 325                         }
 326                         if (slimit0) {
 327                                 op->ors_slimit = slimit0 - gs.nentries;
 328                                 if (op->ors_slimit <= 0) {
 329                                         rs->sr_err = gs.err = LDAP_SIZELIMIT_EXCEEDED;
 330                                         break;
 331                                 }
 332                         }
 333                         rs->sr_err = 0;
 334                         /*
 335                          * check for abandon
 336                          */
 337                         if (op->o_abandon) {
 338                                 goto done;
 339                         }
 340                         op->o_bd = gi->n[i].be;
 341                         if (scope0 == LDAP_SCOPE_ONELEVEL &&
 342                                 dn_match(&gi->n[i].pdn, &ndn)) {
 343                                 op->ors_scope = LDAP_SCOPE_BASE;
 344                                 op->o_req_dn = op->o_bd->be_suffix[0];
 345                                 op->o_req_ndn = op->o_bd->be_nsuffix[0];
 346                                 rs->sr_err = op->o_bd->be_search(op, rs);
 347
 348                         } else if (scope0 == LDAP_SCOPE_SUBTREE &&
 349                                 dnIsSuffix(&op->o_bd->be_nsuffix[0], &ndn)) {
 350                                 op->o_req_dn = op->o_bd->be_suffix[0];
 351                                 op->o_req_ndn = op->o_bd->be_nsuffix[0];
 352                                 rs->sr_err = op->o_bd->be_search( op, rs );
 353
 354                         } else if (dnIsSuffix(&ndn, &op->o_bd->be_nsuffix[0])) {
 355                                 rs->sr_err = op->o_bd->be_search( op, rs );
 356                         }
 357
 358                         switch ( gs.err ) {
 359
 360                         /*
 361                          * Add errors that should result in dropping
 362                          * the search
 363                          */
 364                         case LDAP_SIZELIMIT_EXCEEDED:
 365                         case LDAP_TIMELIMIT_EXCEEDED:
 366                         case LDAP_ADMINLIMIT_EXCEEDED:
 367                                 goto end_of_loop;
 368
 369                         default:
 370                                 break;
 371                         }
 372                 }
 373 end_of_loop:;
 374                 op->ors_scope = scope0;
 375                 op->ors_slimit = slimit0;
 376                 op->ors_tlimit = tlimit0;
 377                 op->o_req_dn = dn;
 378                 op->o_req_ndn = ndn;
 379
 380                 break;
 381         }
 382         op->o_callback = gs.prevcb;
 383         rs->sr_err = gs.err;
 384         rs->sr_matched = gs.matched;
 385         rs->sr_ref = gs.refs;
 386         rs->sr_nentries = gs.nentries;
 387
 388         send_search_result( op, rs );
 389
 390 done:
 391         op->o_bd = b0;
 392         if (gs.matched)
 393                 free (gs.matched);
 394         if (gs.refs)
 395                 ber_bvarray_free(gs.refs);
 396         return rs->sr_err;
 397 }
 398
 399
 400 static int
 401 glue_tool_entry_open (
 402         BackendDB *b0,
 403         int mode
 404 )
 405 {
 406         /* We don't know which backend to talk to yet, so just
 407          * remember the mode and move on...
 408          */
 409
 410         glueMode = mode;
 411         glueBack = NULL;
 412
 413         return 0;
 414 }
 415
 416 static int
 417 glue_tool_entry_close (
 418         BackendDB *b0
 419 )
 420 {
 421         int rc = 0;
 422
 423         if (glueBack) {
 424                 if (!glueBack->be_entry_close)
 425                         return 0;
 426                 rc = glueBack->be_entry_close (glueBack);
 427         }
 428         return rc;
 429 }
 430
 431 static ID
 432 glue_tool_entry_first (
 433         BackendDB *b0
 434 )
 435 {
 436         glueinfo *gi = (glueinfo *) b0->bd_info;
 437         int i;
 438
 439         /* If we're starting from scratch, start at the most general */
 440         if (!glueBack) {
 441                 for (i = gi->nodes-1; i >= 0; i--) {
 442                         if (gi->n[i].be->be_entry_open &&
 443                             gi->n[i].be->be_entry_first) {
 444                                 glueBack = gi->n[i].be;
 445                                 break;
 446                         }
 447                 }
 448
 449         }
 450         if (!glueBack || glueBack->be_entry_open (glueBack, glueMode) != 0)
 451                 return NOID;
 452
 453         return glueBack->be_entry_first (glueBack);
 454 }
 455
 456 static ID
 457 glue_tool_entry_next (
 458         BackendDB *b0
 459 )
 460 {
 461         glueinfo *gi = (glueinfo *) b0->bd_info;
 462         int i;
 463         ID rc;
 464
 465         if (!glueBack || !glueBack->be_entry_next)
 466                 return NOID;
 467
 468         rc = glueBack->be_entry_next (glueBack);
 469
 470         /* If we ran out of entries in one database, move on to the next */
 471         if (rc == NOID) {
 472                 glueBack->be_entry_close (glueBack);
 473                 for (i=0; i<gi->nodes; i++) {
 474                         if (gi->n[i].be == glueBack)
 475                                 break;
 476                 }
 477                 if (i == 0) {
 478                         glueBack = NULL;
 479                         rc = NOID;
 480                 } else {
 481                         glueBack = gi->n[i-1].be;
 482                         rc = glue_tool_entry_first (b0);
 483                 }
 484         }
 485         return rc;
 486 }
 487
 488 static Entry *
 489 glue_tool_entry_get (
 490         BackendDB *b0,
 491         ID id
 492 )
 493 {
 494         if (!glueBack || !glueBack->be_entry_get)
 495                 return NULL;
 496
 497         return glueBack->be_entry_get (glueBack, id);
 498 }
 499
 500 static ID
 501 glue_tool_entry_put (
 502         BackendDB *b0,
 503         Entry *e,
 504         struct berval *text
 505 )
 506 {
 507         BackendDB *be;
 508         int rc;
 509
 510         be = glue_back_select (b0, e->e_ndn);
 511         if (!be->be_entry_put)
 512                 return NOID;
 513
 514         if (!glueBack) {
 515                 rc = be->be_entry_open (be, glueMode);
 516                 if (rc != 0)
 517                         return NOID;
 518         } else if (be != glueBack) {
 519                 /* If this entry belongs in a different branch than the
 520                  * previous one, close the current database and open the
 521                  * new one.
 522                  */
 523                 glueBack->be_entry_close (glueBack);
 524                 rc = be->be_entry_open (be, glueMode);
 525                 if (rc != 0)
 526                         return NOID;
 527         }
 528         glueBack = be;
 529         return be->be_entry_put (be, e, text);
 530 }
 531
 532 static int
 533 glue_tool_entry_reindex (
 534         BackendDB *b0,
 535         ID id
 536 )
 537 {
 538         if (!glueBack || !glueBack->be_entry_reindex)
 539                 return -1;
 540
 541         return glueBack->be_entry_reindex (glueBack, id);
 542 }
 543
 544 static int
 545 glue_tool_sync (
 546         BackendDB *b0
 547 )
 548 {
 549         glueinfo *gi = (glueinfo *) b0->bd_info;
 550         int i;
 551
 552         /* just sync everyone */
 553         for (i = 0; i<gi->nodes; i++)
 554                 if (gi->n[i].be->be_sync)
 555                         gi->n[i].be->be_sync (gi->n[i].be);
 556         return 0;
 557 }
 558
 559 int
 560 glue_sub_init( )
 561 {
 562         int i, j;
 563         int cont = num_subordinates;
 564         BackendDB *b1, *be;
 565         BackendInfo *bi = NULL;
 566         glueinfo *gi;
 567
 568         /* While there are subordinate backends, search backwards through the
 569          * backends and connect them to their superior.
 570          */
 571         for (i = nBackendDB - 1, b1=&backendDB[i]; cont && i>=0; b1--,i--) {
 572                 if (SLAP_GLUE_SUBORDINATE ( b1 ) ) {
 573                         /* The last database cannot be a subordinate of noone */
 574                         if (i == nBackendDB - 1) {
 575                                 b1->be_flags ^= SLAP_BFLAG_GLUE_SUBORDINATE;
 576                         }
 577                         continue;
 578                 }
 579                 gi = NULL;
 580                 for (j = i-1, be=&backendDB[j]; j>=0; be--,j--) {
 581                         if ( ! SLAP_GLUE_SUBORDINATE( be ) ) {
 582                                 continue;
 583                         }
 584                         /* We will only link it once */
 585                         if ( SLAP_GLUE_LINKED( be ) ) {
 586                                 continue;
 587                         }
 588                         if (!dnIsSuffix(&be->be_nsuffix[0], &b1->be_nsuffix[0])) {
 589                                 continue;
 590                         }
 591                         cont--;
 592                         be->be_flags |= SLAP_BFLAG_GLUE_LINKED;
 593                         if (gi == NULL) {
 594                                 /* We create a copy of the superior's be
 595                                  * structure, pointing to all of its original
 596                                  * information. Then we replace elements of
 597                                  * the superior's info with our own. The copy
 598                                  * is used whenever we have operations to pass
 599                                  * down to the real database.
 600                                  */
 601                                 b1->be_flags |= SLAP_BFLAG_GLUE_INSTANCE;
 602                                 gi = (glueinfo *)ch_malloc(sizeof(glueinfo));
 603                                 gi->nodes = 0;
 604                                 gi->bd = *b1;
 605                                 gi->bi = *b1->bd_info;
 606                                 bi = (BackendInfo *)gi;
 607                                 bi->bi_open = glue_back_open;
 608                                 bi->bi_close = glue_back_close;
 609                                 bi->bi_db_open = glue_back_db_open;
 610                                 bi->bi_db_close = glue_back_db_close;
 611                                 bi->bi_db_destroy = glue_back_db_destroy;
 612
 613                                 bi->bi_op_search = glue_back_search;
 614
 615                                 /*
 616                                  * hooks for slap tools
 617                                  */
 618                                 bi->bi_tool_entry_open = glue_tool_entry_open;
 619                                 bi->bi_tool_entry_close = glue_tool_entry_close;
 620                                 bi->bi_tool_entry_first = glue_tool_entry_first;
 621                                 bi->bi_tool_entry_next = glue_tool_entry_next;
 622                                 bi->bi_tool_entry_get = glue_tool_entry_get;
 623                                 bi->bi_tool_entry_put = glue_tool_entry_put;
 624                                 bi->bi_tool_entry_reindex = glue_tool_entry_reindex;
 625                                 bi->bi_tool_sync = glue_tool_sync;
 626                         } else {
 627                                 gi = (glueinfo *)ch_realloc(gi,
 628                                         sizeof(glueinfo) +
 629                                         gi->nodes * sizeof(gluenode));
 630                         }
 631                         gi->n[gi->nodes].be = be;
 632                         dnParent( &be->be_nsuffix[0], &gi->n[gi->nodes].pdn );
 633                         gi->nodes++;
 634                 }
 635                 if (gi) {
 636                         /* One more node for the master */
 637                         gi = (glueinfo *)ch_realloc(gi,
 638                                 sizeof(glueinfo) + gi->nodes * sizeof(gluenode));
 639                         gi->n[gi->nodes].be = &gi->bd;
 640                         dnParent( &b1->be_nsuffix[0], &gi->n[gi->nodes].pdn );
 641                         gi->nodes++;
 642                         b1->bd_info = bi;
 643                 }
 644         }
 645         /* If there are any unresolved subordinates left, something is wrong */
 646         return cont;
 647 }