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 ( op->o_sync_mode & SLAP_SYNC_REFRESH ) {
 293                         if (op->o_bd && op->o_bd->be_search) {
 294                                 rs->sr_err = op->o_bd->be_search( op, rs );
 295                         } else {
 296                                 send_ldap_error(op, rs, LDAP_UNWILLING_TO_PERFORM,
 297                                               "No search target found");
 298                         }
 299                         return rs->sr_err;
 300                 }
 301
 302                 op->o_callback = &cb;
 303                 rs->sr_err = gs.err = LDAP_UNWILLING_TO_PERFORM;
 304                 scope0 = op->ors_scope;
 305                 slimit0 = gs.slimit = op->ors_slimit;
 306                 tlimit0 = op->ors_tlimit;
 307                 dn = op->o_req_dn;
 308                 ndn = op->o_req_ndn;
 309                 b1 = op->o_bd;
 310
 311                 /*
 312                  * Execute in reverse order, most general first
 313                  */
 314                 for (i = gi->gi_nodes-1; i >= 0; i--) {
 315                         if (!gi->gi_n[i].gn_be || !gi->gi_n[i].gn_be->be_search)
 316                                 continue;
 317                         if (!dnIsSuffix(&gi->gi_n[i].gn_be->be_nsuffix[0], &b1->be_nsuffix[0]))
 318                                 continue;
 319                         if (tlimit0 != SLAP_NO_LIMIT) {
 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 != SLAP_NO_LIMIT) {
 327                                 op->ors_slimit = slimit0 - rs->sr_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 end_of_loop;
 339                         }
 340                         op->o_bd = gi->gi_n[i].gn_be;
 341
 342                         assert( op->o_bd->be_suffix );
 343                         assert( op->o_bd->be_nsuffix );
 344
 345                         if (scope0 == LDAP_SCOPE_ONELEVEL &&
 346                                 dn_match(&gi->gi_n[i].gn_pdn, &ndn))
 347                         {
 348                                 op->ors_scope = LDAP_SCOPE_BASE;
 349                                 op->o_req_dn = op->o_bd->be_suffix[0];
 350                                 op->o_req_ndn = op->o_bd->be_nsuffix[0];
 351                                 rs->sr_err = op->o_bd->be_search(op, rs);
 352
 353                         } else if (scope0 == LDAP_SCOPE_SUBTREE &&
 354                                 dn_match(&op->o_bd->be_nsuffix[0], &ndn))
 355                         {
 356                                 rs->sr_err = op->o_bd->be_search( op, rs );
 357
 358                         } else if (scope0 == LDAP_SCOPE_SUBTREE &&
 359                                 dnIsSuffix(&op->o_bd->be_nsuffix[0], &ndn))
 360                         {
 361                                 op->o_req_dn = op->o_bd->be_suffix[0];
 362                                 op->o_req_ndn = op->o_bd->be_nsuffix[0];
 363                                 rs->sr_err = op->o_bd->be_search( op, rs );
 364                                 if ( rs->sr_err == LDAP_NO_SUCH_OBJECT ) {
 365                                         gs.err = LDAP_SUCCESS;
 366                                 }
 367
 368                         } else if (dnIsSuffix(&ndn, &op->o_bd->be_nsuffix[0])) {
 369                                 rs->sr_err = op->o_bd->be_search( op, rs );
 370                         }
 371
 372                         switch ( gs.err ) {
 373
 374                         /*
 375                          * Add errors that should result in dropping
 376                          * the search
 377                          */
 378                         case LDAP_SIZELIMIT_EXCEEDED:
 379                         case LDAP_TIMELIMIT_EXCEEDED:
 380                         case LDAP_ADMINLIMIT_EXCEEDED:
 381                         case LDAP_NO_SUCH_OBJECT:
 382                                 goto end_of_loop;
 383
 384                         default:
 385                                 break;
 386                         }
 387                 }
 388 end_of_loop:;
 389                 op->ors_scope = scope0;
 390                 op->ors_slimit = slimit0;
 391                 op->ors_tlimit = tlimit0;
 392                 op->o_req_dn = dn;
 393                 op->o_req_ndn = ndn;
 394
 395                 break;
 396         }
 397         if ( !op->o_abandon ) {
 398                 op->o_callback = cb.sc_next;
 399                 rs->sr_err = gs.err;
 400                 rs->sr_matched = gs.matched;
 401                 rs->sr_ref = gs.refs;
 402
 403                 send_ldap_result( op, rs );
 404         }
 405
 406         op->o_bd = b0;
 407         if (gs.matched)
 408                 free (gs.matched);
 409         if (gs.refs)
 410                 ber_bvarray_free(gs.refs);
 411         return rs->sr_err;
 412 }
 413
 414
 415 static int
 416 glue_tool_entry_open (
 417         BackendDB *b0,
 418         int mode
 419 )
 420 {
 421         /* We don't know which backend to talk to yet, so just
 422          * remember the mode and move on...
 423          */
 424
 425         glueMode = mode;
 426         glueBack = NULL;
 427
 428         return 0;
 429 }
 430
 431 static int
 432 glue_tool_entry_close (
 433         BackendDB *b0
 434 )
 435 {
 436         int rc = 0;
 437
 438         if (glueBack) {
 439                 if (!glueBack->be_entry_close)
 440                         return 0;
 441                 rc = glueBack->be_entry_close (glueBack);
 442         }
 443         return rc;
 444 }
 445
 446 static ID
 447 glue_tool_entry_first (
 448         BackendDB *b0
 449 )
 450 {
 451         glueinfo *gi = (glueinfo *) b0->bd_info;
 452         int i;
 453
 454         /* If we're starting from scratch, start at the most general */
 455         if (!glueBack) {
 456                 for (i = gi->gi_nodes-1; i >= 0; i--) {
 457                         if (gi->gi_n[i].gn_be->be_entry_open &&
 458                             gi->gi_n[i].gn_be->be_entry_first) {
 459                                 glueBack = gi->gi_n[i].gn_be;
 460                                 break;
 461                         }
 462                 }
 463
 464         }
 465         if (!glueBack || !glueBack->be_entry_open || !glueBack->be_entry_first ||
 466                 glueBack->be_entry_open (glueBack, glueMode) != 0)
 467                 return NOID;
 468
 469         return glueBack->be_entry_first (glueBack);
 470 }
 471
 472 static ID
 473 glue_tool_entry_next (
 474         BackendDB *b0
 475 )
 476 {
 477         glueinfo *gi = (glueinfo *) b0->bd_info;
 478         int i;
 479         ID rc;
 480
 481         if (!glueBack || !glueBack->be_entry_next)
 482                 return NOID;
 483
 484         rc = glueBack->be_entry_next (glueBack);
 485
 486         /* If we ran out of entries in one database, move on to the next */
 487         while (rc == NOID) {
 488                 if ( glueBack && glueBack->be_entry_close )
 489                         glueBack->be_entry_close (glueBack);
 490                 for (i=0; i<gi->gi_nodes; i++) {
 491                         if (gi->gi_n[i].gn_be == glueBack)
 492                                 break;
 493                 }
 494                 if (i == 0) {
 495                         glueBack = NULL;
 496                         break;
 497                 } else {
 498                         glueBack = gi->gi_n[i-1].gn_be;
 499                         rc = glue_tool_entry_first (b0);
 500                 }
 501         }
 502         return rc;
 503 }
 504
 505 static Entry *
 506 glue_tool_entry_get (
 507         BackendDB *b0,
 508         ID id
 509 )
 510 {
 511         if (!glueBack || !glueBack->be_entry_get)
 512                 return NULL;
 513
 514         return glueBack->be_entry_get (glueBack, id);
 515 }
 516
 517 static ID
 518 glue_tool_entry_put (
 519         BackendDB *b0,
 520         Entry *e,
 521         struct berval *text
 522 )
 523 {
 524         BackendDB *be;
 525         int rc;
 526
 527         be = glue_back_select (b0, e->e_ndn);
 528         if (!be->be_entry_put)
 529                 return NOID;
 530
 531         if (!glueBack) {
 532                 rc = be->be_entry_open (be, glueMode);
 533                 if (rc != 0)
 534                         return NOID;
 535         } else if (be != glueBack) {
 536                 /* If this entry belongs in a different branch than the
 537                  * previous one, close the current database and open the
 538                  * new one.
 539                  */
 540                 glueBack->be_entry_close (glueBack);
 541                 rc = be->be_entry_open (be, glueMode);
 542                 if (rc != 0)
 543                         return NOID;
 544         }
 545         glueBack = be;
 546         return be->be_entry_put (be, e, text);
 547 }
 548
 549 static int
 550 glue_tool_entry_reindex (
 551         BackendDB *b0,
 552         ID id
 553 )
 554 {
 555         if (!glueBack || !glueBack->be_entry_reindex)
 556                 return -1;
 557
 558         return glueBack->be_entry_reindex (glueBack, id);
 559 }
 560
 561 static int
 562 glue_tool_sync (
 563         BackendDB *b0
 564 )
 565 {
 566         glueinfo *gi = (glueinfo *) b0->bd_info;
 567         int i;
 568
 569         /* just sync everyone */
 570         for (i = 0; i<gi->gi_nodes; i++)
 571                 if (gi->gi_n[i].gn_be->be_sync)
 572                         gi->gi_n[i].gn_be->be_sync (gi->gi_n[i].gn_be);
 573         return 0;
 574 }
 575
 576 int
 577 glue_sub_init( )
 578 {
 579         int i, j;
 580         int cont = num_subordinates;
 581         BackendDB *b1, *be;
 582         BackendInfo *bi = NULL;
 583         glueinfo *gi;
 584
 585         /* While there are subordinate backends, search backwards through the
 586          * backends and connect them to their superior.
 587          */
 588         for (i = nBackendDB - 1, b1=&backendDB[i]; cont && i>=0; b1--,i--) {
 589                 if (SLAP_GLUE_SUBORDINATE ( b1 ) ) {
 590                         /* The last database cannot be a subordinate of noone */
 591                         if (i == nBackendDB - 1) {
 592                                 SLAP_DBFLAGS(b1) ^= SLAP_DBFLAG_GLUE_SUBORDINATE;
 593                         }
 594                         continue;
 595                 }
 596                 gi = NULL;
 597                 for (j = i-1, be=&backendDB[j]; j>=0; be--,j--) {
 598                         if ( ! SLAP_GLUE_SUBORDINATE( be ) ) {
 599                                 continue;
 600                         }
 601                         /* We will only link it once */
 602                         if ( SLAP_GLUE_LINKED( be ) ) {
 603                                 continue;
 604                         }
 605                         assert( be->be_nsuffix );
 606                         assert( b1->be_nsuffix );
 607                         if (!dnIsSuffix(&be->be_nsuffix[0], &b1->be_nsuffix[0])) {
 608                                 continue;
 609                         }
 610                         cont--;
 611                         SLAP_DBFLAGS(be) |= SLAP_DBFLAG_GLUE_LINKED;
 612                         if (gi == NULL) {
 613                                 /* We create a copy of the superior's be
 614                                  * structure, pointing to all of its original
 615                                  * information. Then we replace elements of
 616                                  * the superior's info with our own. The copy
 617                                  * is used whenever we have operations to pass
 618                                  * down to the real database.
 619                                  */
 620                                 SLAP_DBFLAGS(b1) |= SLAP_DBFLAG_GLUE_INSTANCE;
 621                                 gi = (glueinfo *)ch_malloc(sizeof(glueinfo));
 622                                 gi->gi_nodes = 0;
 623                                 gi->gi_bd = *b1;
 624                                 gi->gi_bi = *b1->bd_info;
 625                                 bi = (BackendInfo *)gi;
 626                                 bi->bi_open = glue_back_open;
 627                                 bi->bi_close = glue_back_close;
 628                                 bi->bi_db_open = glue_back_db_open;
 629                                 bi->bi_db_close = glue_back_db_close;
 630                                 bi->bi_db_destroy = glue_back_db_destroy;
 631
 632                                 bi->bi_op_search = glue_back_search;
 633
 634                                 /*
 635                                  * hooks for slap tools
 636                                  */
 637                                 bi->bi_tool_entry_open = glue_tool_entry_open;
 638                                 bi->bi_tool_entry_close = glue_tool_entry_close;
 639                                 bi->bi_tool_entry_first = glue_tool_entry_first;
 640                                 bi->bi_tool_entry_next = glue_tool_entry_next;
 641                                 bi->bi_tool_entry_get = glue_tool_entry_get;
 642                                 bi->bi_tool_entry_put = glue_tool_entry_put;
 643                                 bi->bi_tool_entry_reindex = glue_tool_entry_reindex;
 644                                 bi->bi_tool_sync = glue_tool_sync;
 645                                 /* FIXME : will support later */
 646                                 bi->bi_tool_dn2id_get = 0;
 647                                 bi->bi_tool_id2entry_get = 0;
 648                                 bi->bi_tool_entry_modify = 0;
 649                         } else {
 650                                 gi = (glueinfo *)ch_realloc(gi,
 651                                         sizeof(glueinfo) +
 652                                         gi->gi_nodes * sizeof(gluenode));
 653                         }
 654                         gi->gi_n[gi->gi_nodes].gn_be = be;
 655                         dnParent( &be->be_nsuffix[0], &gi->gi_n[gi->gi_nodes].gn_pdn );
 656                         gi->gi_nodes++;
 657                 }
 658                 if (gi) {
 659                         /* One more node for the master */
 660                         gi = (glueinfo *)ch_realloc(gi,
 661                                 sizeof(glueinfo) + gi->gi_nodes * sizeof(gluenode));
 662                         gi->gi_n[gi->gi_nodes].gn_be = &gi->gi_bd;
 663                         dnParent( &b1->be_nsuffix[0], &gi->gi_n[gi->gi_nodes].gn_pdn );
 664                         gi->gi_nodes++;
 665                         b1->bd_info = (BackendInfo *)gi;
 666                 }
 667         }
 668         /* If there are any unresolved subordinates left, something is wrong */
 669         return cont;
 670 }