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         gi->bd.be_pending_csn_list = be->be_pending_csn_list;
 142
 143         if (gi->bd.bd_info->bi_db_open)
 144                 rc = gi->bd.bd_info->bi_db_open(&gi->bd);
 145
 146         return rc;
 147 }
 148
 149 static int
 150 glue_back_db_close (
 151         BackendDB *be
 152 )
 153 {
 154         glueinfo *gi = (glueinfo *) be->bd_info;
 155         static int glueClosed = 0;
 156
 157         if (glueClosed) return 0;
 158
 159         glueClosed = 1;
 160
 161         /* Close the master */
 162         if (gi->bd.bd_info->bi_db_close)
 163                 gi->bd.bd_info->bi_db_close( &gi->bd );
 164
 165         return 0;
 166 }
 167
 168 static int
 169 glue_back_db_destroy (
 170         BackendDB *be
 171 )
 172 {
 173         glueinfo *gi = (glueinfo *) be->bd_info;
 174
 175         if (gi->bd.bd_info->bi_db_destroy)
 176                 gi->bd.bd_info->bi_db_destroy( &gi->bd );
 177         free (gi);
 178         return 0;
 179 }
 180
 181 typedef struct glue_state {
 182         int err;
 183         int slimit;
 184         int matchlen;
 185         char *matched;
 186         int nrefs;
 187         BerVarray refs;
 188 } glue_state;
 189
 190 static int
 191 glue_back_response ( Operation *op, SlapReply *rs )
 192 {
 193         glue_state *gs = op->o_callback->sc_private;
 194
 195         switch(rs->sr_type) {
 196         case REP_SEARCH:
 197                 if ( gs->slimit != SLAP_NO_LIMIT
 198                                 && rs->sr_nentries >= gs->slimit )
 199                 {
 200                         rs->sr_err = gs->err = LDAP_SIZELIMIT_EXCEEDED;
 201                         return -1;
 202                 }
 203                 /* fallthru */
 204         case REP_SEARCHREF:
 205                 return SLAP_CB_CONTINUE;
 206
 207         default:
 208                 if (rs->sr_err == LDAP_SUCCESS ||
 209                         rs->sr_err == LDAP_SIZELIMIT_EXCEEDED ||
 210                         rs->sr_err == LDAP_TIMELIMIT_EXCEEDED ||
 211                         rs->sr_err == LDAP_ADMINLIMIT_EXCEEDED ||
 212                         rs->sr_err == LDAP_NO_SUCH_OBJECT ||
 213                         gs->err != LDAP_SUCCESS)
 214                         gs->err = rs->sr_err;
 215                 if (gs->err == LDAP_SUCCESS && gs->matched) {
 216                         ch_free (gs->matched);
 217                         gs->matched = NULL;
 218                         gs->matchlen = 0;
 219                 }
 220                 if (gs->err != LDAP_SUCCESS && rs->sr_matched) {
 221                         int len;
 222                         len = strlen (rs->sr_matched);
 223                         if (len > gs->matchlen) {
 224                                 if (gs->matched)
 225                                         ch_free (gs->matched);
 226                                 gs->matched = ch_strdup (rs->sr_matched);
 227                                 gs->matchlen = len;
 228                         }
 229                 }
 230                 if (rs->sr_ref) {
 231                         int i, j, k;
 232                         BerVarray new;
 233
 234                         for (i=0; rs->sr_ref[i].bv_val; i++);
 235
 236                         j = gs->nrefs;
 237                         if (!j) {
 238                                 new = ch_malloc ((i+1)*sizeof(struct berval));
 239                         } else {
 240                                 new = ch_realloc(gs->refs,
 241                                         (j+i+1)*sizeof(struct berval));
 242                         }
 243                         for (k=0; k<i; j++,k++) {
 244                                 ber_dupbv( &new[j], &rs->sr_ref[k] );
 245                         }
 246                         new[j].bv_val = NULL;
 247                         gs->nrefs = j;
 248                         gs->refs = new;
 249                 }
 250         }
 251         return 0;
 252 }
 253
 254 static int
 255 glue_back_search ( Operation *op, SlapReply *rs )
 256 {
 257         BackendDB *b0 = op->o_bd;
 258         BackendDB *b1 = NULL;
 259         glueinfo *gi = (glueinfo *) b0->bd_info;
 260         int i;
 261         long stoptime = 0;
 262         glue_state gs = {0, 0, 0, NULL, 0, NULL};
 263         slap_callback cb = { NULL, glue_back_response, NULL, NULL };
 264         int scope0, slimit0, tlimit0;
 265         struct berval dn, ndn;
 266
 267         cb.sc_private = &gs;
 268
 269         cb.sc_next = op->o_callback;
 270
 271         stoptime = slap_get_time () + op->ors_tlimit;
 272
 273         op->o_bd = glue_back_select (b0, op->o_req_ndn.bv_val);
 274
 275         switch (op->ors_scope) {
 276         case LDAP_SCOPE_BASE:
 277                 if (op->o_bd && op->o_bd->be_search) {
 278                         rs->sr_err = op->o_bd->be_search( op, rs );
 279                 } else {
 280                         send_ldap_error(op, rs, LDAP_UNWILLING_TO_PERFORM,
 281                                       "No search target found");
 282                 }
 283                 return rs->sr_err;
 284
 285         case LDAP_SCOPE_ONELEVEL:
 286         case LDAP_SCOPE_SUBTREE:
 287 #ifdef LDAP_SCOPE_SUBORDINATE
 288         case LDAP_SCOPE_SUBORDINATE: /* FIXME */
 289 #endif
 290
 291                 if ( op->o_sync_mode & SLAP_SYNC_REFRESH ) {
 292                         if (op->o_bd && op->o_bd->be_search) {
 293                                 rs->sr_err = op->o_bd->be_search( op, rs );
 294                         } else {
 295                                 send_ldap_error(op, rs, LDAP_UNWILLING_TO_PERFORM,
 296                                               "No search target found");
 297                         }
 298                         return rs->sr_err;
 299                 }
 300
 301                 op->o_callback = &cb;
 302                 rs->sr_err = gs.err = LDAP_UNWILLING_TO_PERFORM;
 303                 scope0 = op->ors_scope;
 304                 slimit0 = gs.slimit = op->ors_slimit;
 305                 tlimit0 = op->ors_tlimit;
 306                 dn = op->o_req_dn;
 307                 ndn = op->o_req_ndn;
 308                 b1 = op->o_bd;
 309
 310                 /*
 311                  * Execute in reverse order, most general first
 312                  */
 313                 for (i = gi->nodes-1; i >= 0; i--) {
 314                         if (!gi->n[i].be || !gi->n[i].be->be_search)
 315                                 continue;
 316                         if (!dnIsSuffix(&gi->n[i].be->be_nsuffix[0], &b1->be_nsuffix[0]))
 317                                 continue;
 318                         if (tlimit0 != SLAP_NO_LIMIT) {
 319                                 op->ors_tlimit = stoptime - slap_get_time ();
 320                                 if (op->ors_tlimit <= 0) {
 321                                         rs->sr_err = gs.err = LDAP_TIMELIMIT_EXCEEDED;
 322                                         break;
 323                                 }
 324                         }
 325                         if (slimit0 != SLAP_NO_LIMIT) {
 326                                 op->ors_slimit = slimit0 - rs->sr_nentries;
 327                                 if (op->ors_slimit < 0) {
 328                                         rs->sr_err = gs.err = LDAP_SIZELIMIT_EXCEEDED;
 329                                         break;
 330                                 }
 331                         }
 332                         rs->sr_err = 0;
 333                         /*
 334                          * check for abandon
 335                          */
 336                         if (op->o_abandon) {
 337                                 goto end_of_loop;
 338                         }
 339                         op->o_bd = gi->n[i].be;
 340
 341                         assert( op->o_bd->be_suffix );
 342                         assert( op->o_bd->be_nsuffix );
 343
 344                         if (scope0 == LDAP_SCOPE_ONELEVEL &&
 345                                 dn_match(&gi->n[i].pdn, &ndn))
 346                         {
 347                                 op->ors_scope = LDAP_SCOPE_BASE;
 348                                 op->o_req_dn = op->o_bd->be_suffix[0];
 349                                 op->o_req_ndn = op->o_bd->be_nsuffix[0];
 350                                 rs->sr_err = op->o_bd->be_search(op, rs);
 351
 352                         } else if (scope0 == LDAP_SCOPE_SUBTREE &&
 353                                 dn_match(&op->o_bd->be_nsuffix[0], &ndn))
 354                         {
 355                                 rs->sr_err = op->o_bd->be_search( op, rs );
 356
 357                         } else if (scope0 == LDAP_SCOPE_SUBTREE &&
 358                                 dnIsSuffix(&op->o_bd->be_nsuffix[0], &ndn))
 359                         {
 360                                 op->o_req_dn = op->o_bd->be_suffix[0];
 361                                 op->o_req_ndn = op->o_bd->be_nsuffix[0];
 362                                 rs->sr_err = op->o_bd->be_search( op, rs );
 363                                 if ( rs->sr_err == LDAP_NO_SUCH_OBJECT ) {
 364                                         gs.err = LDAP_SUCCESS;
 365                                 }
 366
 367                         } else if (dnIsSuffix(&ndn, &op->o_bd->be_nsuffix[0])) {
 368                                 rs->sr_err = op->o_bd->be_search( op, rs );
 369                         }
 370
 371                         switch ( gs.err ) {
 372
 373                         /*
 374                          * Add errors that should result in dropping
 375                          * the search
 376                          */
 377                         case LDAP_SIZELIMIT_EXCEEDED:
 378                         case LDAP_TIMELIMIT_EXCEEDED:
 379                         case LDAP_ADMINLIMIT_EXCEEDED:
 380                         case LDAP_NO_SUCH_OBJECT:
 381                                 goto end_of_loop;
 382
 383                         default:
 384                                 break;
 385                         }
 386                 }
 387 end_of_loop:;
 388                 op->ors_scope = scope0;
 389                 op->ors_slimit = slimit0;
 390                 op->ors_tlimit = tlimit0;
 391                 op->o_req_dn = dn;
 392                 op->o_req_ndn = ndn;
 393
 394                 break;
 395         }
 396         if ( !op->o_abandon ) {
 397                 op->o_callback = cb.sc_next;
 398                 rs->sr_err = gs.err;
 399                 rs->sr_matched = gs.matched;
 400                 rs->sr_ref = gs.refs;
 401
 402                 send_ldap_result( op, rs );
 403         }
 404
 405         op->o_bd = b0;
 406         if (gs.matched)
 407                 free (gs.matched);
 408         if (gs.refs)
 409                 ber_bvarray_free(gs.refs);
 410         return rs->sr_err;
 411 }
 412
 413
 414 static int
 415 glue_tool_entry_open (
 416         BackendDB *b0,
 417         int mode
 418 )
 419 {
 420         /* We don't know which backend to talk to yet, so just
 421          * remember the mode and move on...
 422          */
 423
 424         glueMode = mode;
 425         glueBack = NULL;
 426
 427         return 0;
 428 }
 429
 430 static int
 431 glue_tool_entry_close (
 432         BackendDB *b0
 433 )
 434 {
 435         int rc = 0;
 436
 437         if (glueBack) {
 438                 if (!glueBack->be_entry_close)
 439                         return 0;
 440                 rc = glueBack->be_entry_close (glueBack);
 441         }
 442         return rc;
 443 }
 444
 445 static ID
 446 glue_tool_entry_first (
 447         BackendDB *b0
 448 )
 449 {
 450         glueinfo *gi = (glueinfo *) b0->bd_info;
 451         int i;
 452
 453         /* If we're starting from scratch, start at the most general */
 454         if (!glueBack) {
 455                 for (i = gi->nodes-1; i >= 0; i--) {
 456                         if (gi->n[i].be->be_entry_open &&
 457                             gi->n[i].be->be_entry_first) {
 458                                 glueBack = gi->n[i].be;
 459                                 break;
 460                         }
 461                 }
 462
 463         }
 464         if (!glueBack || !glueBack->be_entry_open || !glueBack->be_entry_first ||
 465                 glueBack->be_entry_open (glueBack, glueMode) != 0)
 466                 return NOID;
 467
 468         return glueBack->be_entry_first (glueBack);
 469 }
 470
 471 static ID
 472 glue_tool_entry_next (
 473         BackendDB *b0
 474 )
 475 {
 476         glueinfo *gi = (glueinfo *) b0->bd_info;
 477         int i;
 478         ID rc;
 479
 480         if (!glueBack || !glueBack->be_entry_next)
 481                 return NOID;
 482
 483         rc = glueBack->be_entry_next (glueBack);
 484
 485         /* If we ran out of entries in one database, move on to the next */
 486         while (rc == NOID) {
 487                 if ( glueBack && glueBack->be_entry_close )
 488                         glueBack->be_entry_close (glueBack);
 489                 for (i=0; i<gi->nodes; i++) {
 490                         if (gi->n[i].be == glueBack)
 491                                 break;
 492                 }
 493                 if (i == 0) {
 494                         glueBack = NULL;
 495                         break;
 496                 } else {
 497                         glueBack = gi->n[i-1].be;
 498                         rc = glue_tool_entry_first (b0);
 499                 }
 500         }
 501         return rc;
 502 }
 503
 504 static Entry *
 505 glue_tool_entry_get (
 506         BackendDB *b0,
 507         ID id
 508 )
 509 {
 510         if (!glueBack || !glueBack->be_entry_get)
 511                 return NULL;
 512
 513         return glueBack->be_entry_get (glueBack, id);
 514 }
 515
 516 static ID
 517 glue_tool_entry_put (
 518         BackendDB *b0,
 519         Entry *e,
 520         struct berval *text
 521 )
 522 {
 523         BackendDB *be;
 524         int rc;
 525
 526         be = glue_back_select (b0, e->e_ndn);
 527         if (!be->be_entry_put)
 528                 return NOID;
 529
 530         if (!glueBack) {
 531                 rc = be->be_entry_open (be, glueMode);
 532                 if (rc != 0)
 533                         return NOID;
 534         } else if (be != glueBack) {
 535                 /* If this entry belongs in a different branch than the
 536                  * previous one, close the current database and open the
 537                  * new one.
 538                  */
 539                 glueBack->be_entry_close (glueBack);
 540                 rc = be->be_entry_open (be, glueMode);
 541                 if (rc != 0)
 542                         return NOID;
 543         }
 544         glueBack = be;
 545         return be->be_entry_put (be, e, text);
 546 }
 547
 548 static int
 549 glue_tool_entry_reindex (
 550         BackendDB *b0,
 551         ID id
 552 )
 553 {
 554         if (!glueBack || !glueBack->be_entry_reindex)
 555                 return -1;
 556
 557         return glueBack->be_entry_reindex (glueBack, id);
 558 }
 559
 560 static int
 561 glue_tool_sync (
 562         BackendDB *b0
 563 )
 564 {
 565         glueinfo *gi = (glueinfo *) b0->bd_info;
 566         int i;
 567
 568         /* just sync everyone */
 569         for (i = 0; i<gi->nodes; i++)
 570                 if (gi->n[i].be->be_sync)
 571                         gi->n[i].be->be_sync (gi->n[i].be);
 572         return 0;
 573 }
 574
 575 int
 576 glue_sub_init( )
 577 {
 578         int i, j;
 579         int cont = num_subordinates;
 580         BackendDB *b1, *be;
 581         BackendInfo *bi = NULL;
 582         glueinfo *gi;
 583
 584         /* While there are subordinate backends, search backwards through the
 585          * backends and connect them to their superior.
 586          */
 587         for (i = nBackendDB - 1, b1=&backendDB[i]; cont && i>=0; b1--,i--) {
 588                 if (SLAP_GLUE_SUBORDINATE ( b1 ) ) {
 589                         /* The last database cannot be a subordinate of noone */
 590                         if (i == nBackendDB - 1) {
 591                                 SLAP_DBFLAGS(b1) ^= SLAP_DBFLAG_GLUE_SUBORDINATE;
 592                         }
 593                         continue;
 594                 }
 595                 gi = NULL;
 596                 for (j = i-1, be=&backendDB[j]; j>=0; be--,j--) {
 597                         if ( ! SLAP_GLUE_SUBORDINATE( be ) ) {
 598                                 continue;
 599                         }
 600                         /* We will only link it once */
 601                         if ( SLAP_GLUE_LINKED( be ) ) {
 602                                 continue;
 603                         }
 604                         assert( be->be_nsuffix );
 605                         assert( b1->be_nsuffix );
 606                         if (!dnIsSuffix(&be->be_nsuffix[0], &b1->be_nsuffix[0])) {
 607                                 continue;
 608                         }
 609                         cont--;
 610                         SLAP_DBFLAGS(be) |= SLAP_DBFLAG_GLUE_LINKED;
 611                         if (gi == NULL) {
 612                                 /* We create a copy of the superior's be
 613                                  * structure, pointing to all of its original
 614                                  * information. Then we replace elements of
 615                                  * the superior's info with our own. The copy
 616                                  * is used whenever we have operations to pass
 617                                  * down to the real database.
 618                                  */
 619                                 SLAP_DBFLAGS(b1) |= SLAP_DBFLAG_GLUE_INSTANCE;
 620                                 gi = (glueinfo *)ch_malloc(sizeof(glueinfo));
 621                                 gi->nodes = 0;
 622                                 gi->bd = *b1;
 623                                 gi->bi = *b1->bd_info;
 624                                 bi = (BackendInfo *)gi;
 625                                 bi->bi_open = glue_back_open;
 626                                 bi->bi_close = glue_back_close;
 627                                 bi->bi_db_open = glue_back_db_open;
 628                                 bi->bi_db_close = glue_back_db_close;
 629                                 bi->bi_db_destroy = glue_back_db_destroy;
 630
 631                                 bi->bi_op_search = glue_back_search;
 632
 633                                 /*
 634                                  * hooks for slap tools
 635                                  */
 636                                 bi->bi_tool_entry_open = glue_tool_entry_open;
 637                                 bi->bi_tool_entry_close = glue_tool_entry_close;
 638                                 bi->bi_tool_entry_first = glue_tool_entry_first;
 639                                 bi->bi_tool_entry_next = glue_tool_entry_next;
 640                                 bi->bi_tool_entry_get = glue_tool_entry_get;
 641                                 bi->bi_tool_entry_put = glue_tool_entry_put;
 642                                 bi->bi_tool_entry_reindex = glue_tool_entry_reindex;
 643                                 bi->bi_tool_sync = glue_tool_sync;
 644                                 /* FIXME : will support later */
 645                                 bi->bi_tool_dn2id_get = 0;
 646                                 bi->bi_tool_id2entry_get = 0;
 647                                 bi->bi_tool_entry_modify = 0;
 648                         } else {
 649                                 gi = (glueinfo *)ch_realloc(gi,
 650                                         sizeof(glueinfo) +
 651                                         gi->nodes * sizeof(gluenode));
 652                         }
 653                         gi->n[gi->nodes].be = be;
 654                         dnParent( &be->be_nsuffix[0], &gi->n[gi->nodes].pdn );
 655                         gi->nodes++;
 656                 }
 657                 if (gi) {
 658                         /* One more node for the master */
 659                         gi = (glueinfo *)ch_realloc(gi,
 660                                 sizeof(glueinfo) + gi->nodes * sizeof(gluenode));
 661                         gi->n[gi->nodes].be = &gi->bd;
 662                         dnParent( &b1->be_nsuffix[0], &gi->n[gi->nodes].pdn );
 663                         gi->nodes++;
 664                         b1->bd_info = (BackendInfo *)gi;
 665                 }
 666         }
 667         /* If there are any unresolved subordinates left, something is wrong */
 668         return cont;
 669 }