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 *gn_be;
  49         struct berval gn_pdn;
  50 } gluenode;
  51
  52 typedef struct glueinfo {
  53         BackendInfo gi_bi;
  54         BackendDB gi_bd;
  55         int gi_nodes;
  56         gluenode gi_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->gi_nodes; i++) {
  79                 assert( gi->gi_n[i].gn_be->be_nsuffix );
  80
  81                 if (dnIsSuffix(&bv, &gi->gi_n[i].gn_be->be_nsuffix[0])) {
  82                         return gi->gi_n[i].gn_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->gi_bd.be_acl = be->be_acl;
 141         gi->gi_bd.be_pending_csn_list = be->be_pending_csn_list;
 142         gi->gi_bd.be_context_csn = be->be_context_csn;
 143
 144         if (gi->gi_bd.bd_info->bi_db_open)
 145                 rc = gi->gi_bd.bd_info->bi_db_open(&gi->gi_bd);
 146
 147         return rc;
 148 }
 149
 150 static int
 151 glue_back_db_close (
 152         BackendDB *be
 153 )
 154 {
 155         glueinfo *gi = (glueinfo *) be->bd_info;
 156         static int glueClosed = 0;
 157
 158         if (glueClosed) return 0;
 159
 160         glueClosed = 1;
 161
 162         /* Close the master */
 163         if (gi->gi_bd.bd_info->bi_db_close)
 164                 gi->gi_bd.bd_info->bi_db_close( &gi->gi_bd );
 165
 166         return 0;
 167 }
 168
 169 static int
 170 glue_back_db_destroy (
 171         BackendDB *be
 172 )
 173 {
 174         glueinfo *gi = (glueinfo *) be->bd_info;
 175
 176         if (gi->gi_bd.bd_info->bi_db_destroy)
 177                 gi->gi_bd.bd_info->bi_db_destroy( &gi->gi_bd );
 178         free (gi);
 179         return 0;
 180 }
 181
 182 typedef struct glue_state {
 183         int err;
 184         int slimit;
 185         int matchlen;
 186         char *matched;
 187         int nrefs;
 188         BerVarray refs;
 189 } glue_state;
 190
 191 static int
 192 glue_back_response ( Operation *op, SlapReply *rs )
 193 {
 194         glue_state *gs = op->o_callback->sc_private;
 195
 196         switch(rs->sr_type) {
 197         case REP_SEARCH:
 198                 if ( gs->slimit != SLAP_NO_LIMIT
 199                                 && rs->sr_nentries >= gs->slimit )
 200                 {
 201                         rs->sr_err = gs->err = LDAP_SIZELIMIT_EXCEEDED;
 202                         return -1;
 203                 }
 204                 /* fallthru */
 205         case REP_SEARCHREF:
 206                 return SLAP_CB_CONTINUE;
 207
 208         default:
 209                 if (rs->sr_err == LDAP_SUCCESS ||
 210                         rs->sr_err == LDAP_SIZELIMIT_EXCEEDED ||
 211                         rs->sr_err == LDAP_TIMELIMIT_EXCEEDED ||
 212                         rs->sr_err == LDAP_ADMINLIMIT_EXCEEDED ||
 213                         rs->sr_err == LDAP_NO_SUCH_OBJECT ||
 214                         gs->err != LDAP_SUCCESS)
 215                         gs->err = rs->sr_err;
 216                 if (gs->err == LDAP_SUCCESS && gs->matched) {
 217                         ch_free (gs->matched);
 218                         gs->matched = NULL;
 219                         gs->matchlen = 0;
 220                 }
 221                 if (gs->err != LDAP_SUCCESS && rs->sr_matched) {
 222                         int len;
 223                         len = strlen (rs->sr_matched);
 224                         if (len > gs->matchlen) {
 225                                 if (gs->matched)
 226                                         ch_free (gs->matched);
 227                                 gs->matched = ch_strdup (rs->sr_matched);
 228                                 gs->matchlen = len;
 229                         }
 230                 }
 231                 if (rs->sr_ref) {
 232                         int i, j, k;
 233                         BerVarray new;
 234
 235                         for (i=0; rs->sr_ref[i].bv_val; i++);
 236
 237                         j = gs->nrefs;
 238                         if (!j) {
 239                                 new = ch_malloc ((i+1)*sizeof(struct berval));
 240                         } else {
 241                                 new = ch_realloc(gs->refs,
 242                                         (j+i+1)*sizeof(struct berval));
 243                         }
 244                         for (k=0; k<i; j++,k++) {
 245                                 ber_dupbv( &new[j], &rs->sr_ref[k] );
 246                         }
 247                         new[j].bv_val = NULL;
 248                         gs->nrefs = j;
 249                         gs->refs = new;
 250                 }
 251         }
 252         return 0;
 253 }
 254
 255 static int
 256 glue_back_search ( Operation *op, SlapReply *rs )
 257 {
 258         BackendDB *b0 = op->o_bd;
 259         BackendDB *b1 = NULL;
 260         glueinfo *gi = (glueinfo *) b0->bd_info;
 261         int i;
 262         long stoptime = 0;
 263         glue_state gs = {0, 0, 0, NULL, 0, NULL};
 264         slap_callback cb = { NULL, glue_back_response, NULL, NULL };
 265         int scope0, slimit0, tlimit0;
 266         struct berval dn, ndn;
 267
 268         cb.sc_private = &gs;
 269
 270         cb.sc_next = op->o_callback;
 271
 272         stoptime = slap_get_time () + op->ors_tlimit;
 273
 274         op->o_bd = glue_back_select (b0, op->o_req_ndn.bv_val);
 275
 276         switch (op->ors_scope) {
 277         case LDAP_SCOPE_BASE:
 278                 if (op->o_bd && op->o_bd->be_search) {
 279                         rs->sr_err = op->o_bd->be_search( op, rs );
 280                 } else {
 281                         send_ldap_error(op, rs, LDAP_UNWILLING_TO_PERFORM,
 282                                       "No search target found");
 283                 }
 284                 return rs->sr_err;
 285
 286         case LDAP_SCOPE_ONELEVEL:
 287         case LDAP_SCOPE_SUBTREE:
 288 #ifdef LDAP_SCOPE_SUBORDINATE
 289         case LDAP_SCOPE_SUBORDINATE: /* FIXME */
 290 #endif
 291
 292 #if 0   /* DELETE ME - verify ITS first */
 293                 if ( op->o_sync_mode & SLAP_SYNC_REFRESH ) {
 294                         if (op->o_bd && op->o_bd->be_search) {
 295                                 rs->sr_err = op->o_bd->be_search( op, rs );
 296                         } else {
 297                                 send_ldap_error(op, rs, LDAP_UNWILLING_TO_PERFORM,
 298                                               "No search target found");
 299                         }
 300                         return rs->sr_err;
 301                 }
 302 #endif
 303
 304                 op->o_callback = &cb;
 305                 rs->sr_err = gs.err = LDAP_UNWILLING_TO_PERFORM;
 306                 scope0 = op->ors_scope;
 307                 slimit0 = gs.slimit = op->ors_slimit;
 308                 tlimit0 = op->ors_tlimit;
 309                 dn = op->o_req_dn;
 310                 ndn = op->o_req_ndn;
 311                 b1 = op->o_bd;
 312
 313                 /*
 314                  * Execute in reverse order, most general first
 315                  */
 316                 for (i = gi->gi_nodes-1; i >= 0; i--) {
 317                         if (!gi->gi_n[i].gn_be || !gi->gi_n[i].gn_be->be_search)
 318                                 continue;
 319                         if (!dnIsSuffix(&gi->gi_n[i].gn_be->be_nsuffix[0], &b1->be_nsuffix[0]))
 320                                 continue;
 321                         if (tlimit0 != SLAP_NO_LIMIT) {
 322                                 op->ors_tlimit = stoptime - slap_get_time ();
 323                                 if (op->ors_tlimit <= 0) {
 324                                         rs->sr_err = gs.err = LDAP_TIMELIMIT_EXCEEDED;
 325                                         break;
 326                                 }
 327                         }
 328                         if (slimit0 != SLAP_NO_LIMIT) {
 329                                 op->ors_slimit = slimit0 - rs->sr_nentries;
 330                                 if (op->ors_slimit < 0) {
 331                                         rs->sr_err = gs.err = LDAP_SIZELIMIT_EXCEEDED;
 332                                         break;
 333                                 }
 334                         }
 335                         rs->sr_err = 0;
 336                         /*
 337                          * check for abandon
 338                          */
 339                         if (op->o_abandon) {
 340                                 goto end_of_loop;
 341                         }
 342                         op->o_bd = gi->gi_n[i].gn_be;
 343
 344                         assert( op->o_bd->be_suffix );
 345                         assert( op->o_bd->be_nsuffix );
 346
 347                         if (scope0 == LDAP_SCOPE_ONELEVEL &&
 348                                 dn_match(&gi->gi_n[i].gn_pdn, &ndn))
 349                         {
 350                                 op->ors_scope = LDAP_SCOPE_BASE;
 351                                 op->o_req_dn = op->o_bd->be_suffix[0];
 352                                 op->o_req_ndn = op->o_bd->be_nsuffix[0];
 353                                 rs->sr_err = op->o_bd->be_search(op, rs);
 354
 355                         } else if (scope0 == LDAP_SCOPE_SUBTREE &&
 356                                 dn_match(&op->o_bd->be_nsuffix[0], &ndn))
 357                         {
 358                                 rs->sr_err = op->o_bd->be_search( op, rs );
 359
 360                         } else if (scope0 == LDAP_SCOPE_SUBTREE &&
 361                                 dnIsSuffix(&op->o_bd->be_nsuffix[0], &ndn))
 362                         {
 363                                 op->o_req_dn = op->o_bd->be_suffix[0];
 364                                 op->o_req_ndn = op->o_bd->be_nsuffix[0];
 365                                 rs->sr_err = op->o_bd->be_search( op, rs );
 366                                 if ( rs->sr_err == LDAP_NO_SUCH_OBJECT ) {
 367                                         gs.err = LDAP_SUCCESS;
 368                                 }
 369
 370                         } else if (dnIsSuffix(&ndn, &op->o_bd->be_nsuffix[0])) {
 371                                 rs->sr_err = op->o_bd->be_search( op, rs );
 372                         }
 373
 374                         switch ( gs.err ) {
 375
 376                         /*
 377                          * Add errors that should result in dropping
 378                          * the search
 379                          */
 380                         case LDAP_SIZELIMIT_EXCEEDED:
 381                         case LDAP_TIMELIMIT_EXCEEDED:
 382                         case LDAP_ADMINLIMIT_EXCEEDED:
 383                         case LDAP_NO_SUCH_OBJECT:
 384                                 goto end_of_loop;
 385
 386                         default:
 387                                 break;
 388                         }
 389                 }
 390 end_of_loop:;
 391                 op->ors_scope = scope0;
 392                 op->ors_slimit = slimit0;
 393                 op->ors_tlimit = tlimit0;
 394                 op->o_req_dn = dn;
 395                 op->o_req_ndn = ndn;
 396
 397                 break;
 398         }
 399         if ( !op->o_abandon ) {
 400                 op->o_callback = cb.sc_next;
 401                 rs->sr_err = gs.err;
 402                 rs->sr_matched = gs.matched;
 403                 rs->sr_ref = gs.refs;
 404
 405                 send_ldap_result( op, rs );
 406         }
 407
 408         op->o_bd = b0;
 409         if (gs.matched)
 410                 free (gs.matched);
 411         if (gs.refs)
 412                 ber_bvarray_free(gs.refs);
 413         return rs->sr_err;
 414 }
 415
 416
 417 static int
 418 glue_tool_entry_open (
 419         BackendDB *b0,
 420         int mode
 421 )
 422 {
 423         /* We don't know which backend to talk to yet, so just
 424          * remember the mode and move on...
 425          */
 426
 427         glueMode = mode;
 428         glueBack = NULL;
 429
 430         return 0;
 431 }
 432
 433 static int
 434 glue_tool_entry_close (
 435         BackendDB *b0
 436 )
 437 {
 438         int rc = 0;
 439
 440         if (glueBack) {
 441                 if (!glueBack->be_entry_close)
 442                         return 0;
 443                 rc = glueBack->be_entry_close (glueBack);
 444         }
 445         return rc;
 446 }
 447
 448 static ID
 449 glue_tool_entry_first (
 450         BackendDB *b0
 451 )
 452 {
 453         glueinfo *gi = (glueinfo *) b0->bd_info;
 454         int i;
 455
 456         /* If we're starting from scratch, start at the most general */
 457         if (!glueBack) {
 458                 for (i = gi->gi_nodes-1; i >= 0; i--) {
 459                         if (gi->gi_n[i].gn_be->be_entry_open &&
 460                             gi->gi_n[i].gn_be->be_entry_first) {
 461                                 glueBack = gi->gi_n[i].gn_be;
 462                                 break;
 463                         }
 464                 }
 465
 466         }
 467         if (!glueBack || !glueBack->be_entry_open || !glueBack->be_entry_first ||
 468                 glueBack->be_entry_open (glueBack, glueMode) != 0)
 469                 return NOID;
 470
 471         return glueBack->be_entry_first (glueBack);
 472 }
 473
 474 static ID
 475 glue_tool_entry_next (
 476         BackendDB *b0
 477 )
 478 {
 479         glueinfo *gi = (glueinfo *) b0->bd_info;
 480         int i;
 481         ID rc;
 482
 483         if (!glueBack || !glueBack->be_entry_next)
 484                 return NOID;
 485
 486         rc = glueBack->be_entry_next (glueBack);
 487
 488         /* If we ran out of entries in one database, move on to the next */
 489         while (rc == NOID) {
 490                 if ( glueBack && glueBack->be_entry_close )
 491                         glueBack->be_entry_close (glueBack);
 492                 for (i=0; i<gi->gi_nodes; i++) {
 493                         if (gi->gi_n[i].gn_be == glueBack)
 494                                 break;
 495                 }
 496                 if (i == 0) {
 497                         glueBack = NULL;
 498                         break;
 499                 } else {
 500                         glueBack = gi->gi_n[i-1].gn_be;
 501                         rc = glue_tool_entry_first (b0);
 502                 }
 503         }
 504         return rc;
 505 }
 506
 507 static Entry *
 508 glue_tool_entry_get (
 509         BackendDB *b0,
 510         ID id
 511 )
 512 {
 513         if (!glueBack || !glueBack->be_entry_get)
 514                 return NULL;
 515
 516         return glueBack->be_entry_get (glueBack, id);
 517 }
 518
 519 static ID
 520 glue_tool_entry_put (
 521         BackendDB *b0,
 522         Entry *e,
 523         struct berval *text
 524 )
 525 {
 526         BackendDB *be;
 527         int rc;
 528
 529         be = glue_back_select (b0, e->e_ndn);
 530         if (!be->be_entry_put)
 531                 return NOID;
 532
 533         if (!glueBack) {
 534                 rc = be->be_entry_open (be, glueMode);
 535                 if (rc != 0)
 536                         return NOID;
 537         } else if (be != glueBack) {
 538                 /* If this entry belongs in a different branch than the
 539                  * previous one, close the current database and open the
 540                  * new one.
 541                  */
 542                 glueBack->be_entry_close (glueBack);
 543                 rc = be->be_entry_open (be, glueMode);
 544                 if (rc != 0)
 545                         return NOID;
 546         }
 547         glueBack = be;
 548         return be->be_entry_put (be, e, text);
 549 }
 550
 551 static int
 552 glue_tool_entry_reindex (
 553         BackendDB *b0,
 554         ID id
 555 )
 556 {
 557         if (!glueBack || !glueBack->be_entry_reindex)
 558                 return -1;
 559
 560         return glueBack->be_entry_reindex (glueBack, id);
 561 }
 562
 563 static int
 564 glue_tool_sync (
 565         BackendDB *b0
 566 )
 567 {
 568         glueinfo *gi = (glueinfo *) b0->bd_info;
 569         int i;
 570
 571         /* just sync everyone */
 572         for (i = 0; i<gi->gi_nodes; i++)
 573                 if (gi->gi_n[i].gn_be->be_sync)
 574                         gi->gi_n[i].gn_be->be_sync (gi->gi_n[i].gn_be);
 575         return 0;
 576 }
 577
 578 int
 579 glue_sub_init( )
 580 {
 581         int i, j;
 582         int cont = num_subordinates;
 583         BackendDB *b1, *be;
 584         BackendInfo *bi = NULL;
 585         glueinfo *gi;
 586
 587         /* While there are subordinate backends, search backwards through the
 588          * backends and connect them to their superior.
 589          */
 590         for (i = nBackendDB - 1, b1=&backendDB[i]; cont && i>=0; b1--,i--) {
 591                 if (SLAP_GLUE_SUBORDINATE ( b1 ) ) {
 592                         /* The last database cannot be a subordinate of noone */
 593                         if (i == nBackendDB - 1) {
 594                                 SLAP_DBFLAGS(b1) ^= SLAP_DBFLAG_GLUE_SUBORDINATE;
 595                         }
 596                         continue;
 597                 }
 598                 gi = NULL;
 599                 for (j = i-1, be=&backendDB[j]; j>=0; be--,j--) {
 600                         if ( ! SLAP_GLUE_SUBORDINATE( be ) ) {
 601                                 continue;
 602                         }
 603                         /* We will only link it once */
 604                         if ( SLAP_GLUE_LINKED( be ) ) {
 605                                 continue;
 606                         }
 607                         assert( be->be_nsuffix );
 608                         assert( b1->be_nsuffix );
 609                         if (!dnIsSuffix(&be->be_nsuffix[0], &b1->be_nsuffix[0])) {
 610                                 continue;
 611                         }
 612                         cont--;
 613                         SLAP_DBFLAGS(be) |= SLAP_DBFLAG_GLUE_LINKED;
 614                         if (gi == NULL) {
 615                                 /* We create a copy of the superior's be
 616                                  * structure, pointing to all of its original
 617                                  * information. Then we replace elements of
 618                                  * the superior's info with our own. The copy
 619                                  * is used whenever we have operations to pass
 620                                  * down to the real database.
 621                                  */
 622                                 SLAP_DBFLAGS(b1) |= SLAP_DBFLAG_GLUE_INSTANCE;
 623                                 gi = (glueinfo *)ch_malloc(sizeof(glueinfo));
 624                                 gi->gi_nodes = 0;
 625                                 gi->gi_bd = *b1;
 626                                 gi->gi_bi = *b1->bd_info;
 627                                 bi = (BackendInfo *)gi;
 628                                 bi->bi_open = glue_back_open;
 629                                 bi->bi_close = glue_back_close;
 630                                 bi->bi_db_open = glue_back_db_open;
 631                                 bi->bi_db_close = glue_back_db_close;
 632                                 bi->bi_db_destroy = glue_back_db_destroy;
 633
 634                                 bi->bi_op_search = glue_back_search;
 635
 636                                 /*
 637                                  * hooks for slap tools
 638                                  */
 639                                 bi->bi_tool_entry_open = glue_tool_entry_open;
 640                                 bi->bi_tool_entry_close = glue_tool_entry_close;
 641                                 bi->bi_tool_entry_first = glue_tool_entry_first;
 642                                 bi->bi_tool_entry_next = glue_tool_entry_next;
 643                                 bi->bi_tool_entry_get = glue_tool_entry_get;
 644                                 bi->bi_tool_entry_put = glue_tool_entry_put;
 645                                 bi->bi_tool_entry_reindex = glue_tool_entry_reindex;
 646                                 bi->bi_tool_sync = glue_tool_sync;
 647                                 /* FIXME : will support later */
 648                                 bi->bi_tool_dn2id_get = 0;
 649                                 bi->bi_tool_id2entry_get = 0;
 650                                 bi->bi_tool_entry_modify = 0;
 651                         } else {
 652                                 gi = (glueinfo *)ch_realloc(gi,
 653                                         sizeof(glueinfo) +
 654                                         gi->gi_nodes * sizeof(gluenode));
 655                         }
 656                         gi->gi_n[gi->gi_nodes].gn_be = be;
 657                         dnParent( &be->be_nsuffix[0], &gi->gi_n[gi->gi_nodes].gn_pdn );
 658                         gi->gi_nodes++;
 659                 }
 660                 if (gi) {
 661                         /* One more node for the master */
 662                         gi = (glueinfo *)ch_realloc(gi,
 663                                 sizeof(glueinfo) + gi->gi_nodes * sizeof(gluenode));
 664                         gi->gi_n[gi->gi_nodes].gn_be = &gi->gi_bd;
 665                         dnParent( &b1->be_nsuffix[0], &gi->gi_n[gi->gi_nodes].gn_pdn );
 666                         gi->gi_nodes++;
 667                         b1->bd_info = (BackendInfo *)gi;
 668                 }
 669         }
 670         /* If there are any unresolved subordinates left, something is wrong */
 671         return cont;
 672 }