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