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

   1 /* deref.c - dereference overlay */
   2 /* $OpenLDAP$ */
   3 /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
   4  *
   5  * Copyright 1998-2008 The OpenLDAP Foundation.
   6  * Portions Copyright 2008 Pierangelo Masarati.
   7  * All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted only as authorized by the OpenLDAP
  11  * Public License.
  12  *
  13  * A copy of this license is available in the file LICENSE in the
  14  * top-level directory of the distribution or, alternatively, at
  15  * <http://www.OpenLDAP.org/license.html>.
  16  */
  17 /* ACKNOWLEDGEMENTS:
  18  * This work was initially developed by Pierangelo Masarati
  19  * for inclusion in OpenLDAP Software.
  20  */
  21
  22 #include "portable.h"
  23
  24 #ifdef SLAPD_OVER_DEREF
  25
  26 #include <stdio.h>
  27
  28 #include "ac/string.h"
  29 #include "ac/socket.h"
  30
  31 #include "slap.h"
  32 #include "config.h"
  33
  34 #include "lutil.h"
  35
  36 /*
  37  * 1. Specification
  38  *
  39  * 1.1. Request
  40  *
  41  *  controlValue ::= SEQUENCE OF derefSpec DerefSpec
  42  *
  43  *  DerefSpec ::= SEQUENCE {
  44  *      derefAttr       attributeDescription,    ; DN-valued
  45  *      attributes      AttributeList }
  46  *
  47  *  AttributeList ::= SEQUENCE OF attr AttributeDescription
  48  *
  49  *  derefAttr MUST be unique within controlValue
  50  *
  51  *
  52  * 1.2. Response
  53  *
  54  *  controlValue ::= SEQUENCE OF DerefRes
  55  *
  56  * From RFC 4511:
  57  *      PartialAttribute ::= SEQUENCE {
  58  *           type       AttributeDescription,
  59  *           vals       SET OF value AttributeValue }
  60  *
  61  *      PartialAttributeList ::= SEQUENCE OF
  62  *                           partialAttribute PartialAttribute
  63  *
  64  *  DerefRes ::= SEQUENCE {
  65  *      derefAttr       AttributeDescription,
  66  *      derefVal        LDAPDN,
  67  *      attrVals        [0] PartialAttributeList OPTIONAL }
  68  *
  69  *  If vals is empty, partialAttribute is omitted.
  70  *  If all vals in attrVals are empty, attrVals is omitted.
  71  *
  72  * 2. Examples
  73  *
  74  * 2.1. Example
  75  *
  76  * 2.1.1. Request
  77  *
  78  * { { member, { GUID, SID } }, { memberOf, { GUID, SID } } }
  79  *
  80  * 2.1.2. Response
  81  *
  82  * { { memberOf, "cn=abartlet,cn=users,dc=abartlet,dc=net",
  83  *     { { GUID, [ "0bc11d00-e431-40a0-8767-344a320142fa" ] },
  84  *       { SID, [ "S-1-2-3-2345" ] } } },
  85  *   { memberOf, "cn=ando,cn=users,dc=sys-net,dc=it",
  86  *     { { GUID, [ "0bc11d00-e431-40a0-8767-344a320142fb" ] },
  87  *       { SID, [ "S-1-2-3-2346" ] } } } }
  88  *
  89  * 2.2. Example
  90  *
  91  * 2.2.1. Request
  92  *
  93  * { { member, { cn, uid, drink } } }
  94  *
  95  * 2.2.2. Response
  96  *
  97  * { { member, "cn=ando,cn=users,dc=sys-net,dc=it",
  98  *     { { cn, [ "ando", "Pierangelo Masarati" ] },
  99  *       { uid, [ "ando" ] } } },
 100  *   { member, "dc=sys-net,dc=it" } }
 101  *
 102  *
 103  * 3. Security considerations
 104  *
 105  * The control result must not disclose information the client's
 106  * identity could not have accessed directly by performing the related
 107  * search operations.  The presence of a derefVal in the control
 108  * response does not imply neither the existence of nor any access
 109  * privilege to the corresponding entry.  It is merely a consequence
 110  * of the read access the client's identity has on the corresponding
 111  * attribute's value.
 112  */
 113
 114 #define o_deref                 o_ctrlflag[deref_cid]
 115 #define o_ctrlderef             o_controls[deref_cid]
 116
 117 typedef struct DerefSpec {
 118         AttributeDescription    *ds_derefAttr;
 119         AttributeDescription    **ds_attributes;
 120         int                     ds_nattrs;
 121         struct DerefSpec        *ds_next;
 122 } DerefSpec;
 123
 124 typedef struct DerefVal {
 125         struct berval   dv_derefSpecVal;
 126         BerVarray       *dv_attrVals;
 127 } DerefVal;
 128
 129 typedef struct DerefRes {
 130         DerefSpec               dr_spec;
 131         DerefVal                *dr_vals;
 132         struct DerefRes         *dr_next;
 133 } DerefRes;
 134
 135 typedef struct deref_cb_t {
 136         slap_overinst *dc_on;
 137         DerefSpec *dc_ds;
 138 } deref_cb_t;
 139
 140 static int                      deref_cid;
 141 static slap_overinst            deref;
 142
 143 static int
 144 deref_parseCtrl (
 145         Operation *op,
 146         SlapReply *rs,
 147         LDAPControl *ctrl )
 148 {
 149         ber_tag_t tag;
 150         BerElementBuffer berbuf;
 151         BerElement *ber = (BerElement *)&berbuf;
 152         ber_len_t len;
 153         char *last;
 154         DerefSpec *dshead = NULL, **dsp = &dshead;
 155         BerVarray attributes = NULL;
 156
 157         if ( op->o_deref != SLAP_CONTROL_NONE ) {
 158                 rs->sr_text = "Dereference control specified multiple times";
 159                 return LDAP_PROTOCOL_ERROR;
 160         }
 161
 162         if ( BER_BVISNULL( &ctrl->ldctl_value ) ) {
 163                 rs->sr_text = "Dereference control value is absent";
 164                 return LDAP_PROTOCOL_ERROR;
 165         }
 166
 167         if ( BER_BVISEMPTY( &ctrl->ldctl_value ) ) {
 168                 rs->sr_text = "Dereference control value is empty";
 169                 return LDAP_PROTOCOL_ERROR;
 170         }
 171
 172         ber_init2( ber, &ctrl->ldctl_value, 0 );
 173
 174         for ( tag = ber_first_element( ber, &len, &last );
 175                 tag != LBER_DEFAULT;
 176                 tag = ber_next_element( ber, &len, last ) )
 177         {
 178                 struct berval derefAttr;
 179                 DerefSpec *ds, *dstmp;
 180                 const char *text;
 181                 int rc;
 182                 ber_len_t cnt = sizeof(struct berval);
 183                 ber_len_t off = 0;
 184
 185                 if ( ber_scanf( ber, "{m{M}}", &derefAttr, &attributes, &cnt, off ) == LBER_ERROR )
 186                 {
 187                         rs->sr_text = "Dereference control: derefSpec decoding error";
 188                         rs->sr_err = LDAP_PROTOCOL_ERROR;
 189                         goto done;
 190                 }
 191
 192                 ds = (DerefSpec *)op->o_tmpcalloc( 1,
 193                         sizeof(DerefSpec) + sizeof(AttributeDescription *)*(cnt + 1),
 194                         op->o_tmpmemctx );
 195                 ds->ds_attributes = (AttributeDescription **)&ds[1];
 196                 ds->ds_nattrs = cnt;
 197
 198                 rc = slap_bv2ad( &derefAttr, &ds->ds_derefAttr, &text );
 199                 if ( rc != LDAP_SUCCESS ) {
 200                         rs->sr_text = "Dereference control: derefAttr decoding error";
 201                         rs->sr_err = LDAP_PROTOCOL_ERROR;
 202                         goto done;
 203                 }
 204
 205                 for ( dstmp = dshead; dstmp && dstmp != ds; dstmp = dstmp->ds_next ) {
 206                         if ( dstmp->ds_derefAttr == ds->ds_derefAttr ) {
 207                                 rs->sr_text = "Dereference control: derefAttr must be unique within control";
 208                                 rs->sr_err = LDAP_PROTOCOL_ERROR;
 209                                 goto done;
 210                         }
 211                 }
 212
 213                 if ( ds->ds_derefAttr->ad_type->sat_syntax != slap_schema.si_syn_distinguishedName ) {
 214                         if ( ctrl->ldctl_iscritical ) {
 215                                 rs->sr_text = "Dereference control: derefAttr syntax not distinguishedName";
 216                                 rs->sr_err = LDAP_PROTOCOL_ERROR;
 217                                 goto done;
 218                         }
 219
 220                         rs->sr_err = LDAP_SUCCESS;
 221                         goto justcleanup;
 222                 }
 223
 224                 for ( cnt = 0; !BER_BVISNULL( &attributes[ cnt ] ); cnt++ ) {
 225                         rc = slap_bv2ad( &attributes[ cnt ], &ds->ds_attributes[ cnt ], &text );
 226                         if ( rc != LDAP_SUCCESS ) {
 227                                 rs->sr_text = "Dereference control: attribute decoding error";
 228                                 rs->sr_err = LDAP_PROTOCOL_ERROR;
 229                                 goto done;
 230                         }
 231                 }
 232
 233                 ber_memfree_x( attributes, op->o_tmpmemctx );
 234                 attributes = NULL;
 235
 236                 *dsp = ds;
 237                 dsp = &ds->ds_next;
 238         }
 239
 240         op->o_ctrlderef = (void *)dshead;
 241
 242         op->o_deref = ctrl->ldctl_iscritical
 243                 ? SLAP_CONTROL_CRITICAL
 244                 : SLAP_CONTROL_NONCRITICAL;
 245
 246         rs->sr_err = LDAP_SUCCESS;
 247
 248 done:;
 249         if ( rs->sr_err != LDAP_SUCCESS ) {
 250 justcleanup:;
 251                 for ( ; dshead; ) {
 252                         DerefSpec *dsnext = dshead->ds_next;
 253                         op->o_tmpfree( dshead, op->o_tmpmemctx );
 254                         dshead = dsnext;
 255                 }
 256         }
 257
 258         if ( attributes != NULL ) {
 259                 ber_memfree_x( attributes, op->o_tmpmemctx );
 260         }
 261
 262         return rs->sr_err;
 263 }
 264
 265 static int
 266 deref_response( Operation *op, SlapReply *rs )
 267 {
 268         int rc = SLAP_CB_CONTINUE;
 269
 270         if ( rs->sr_type == REP_SEARCH ) {
 271                 BerElementBuffer berbuf;
 272                 BerElement *ber = (BerElement *) &berbuf;
 273                 deref_cb_t *dc = (deref_cb_t *)op->o_callback->sc_private;
 274                 DerefSpec *ds;
 275                 DerefRes *dr, *drhead = NULL, **drp = &drhead;
 276                 BackendInfo *bi = op->o_bd->bd_info;
 277                 struct berval bv = BER_BVNULL;
 278                 int nDerefRes = 0, nDerefVals = 0, nAttrs = 0, nVals = 0;
 279                 struct berval ctrlval;
 280                 LDAPControl *ctrl, **ctrlsp;
 281                 AccessControlState acl_state = ACL_STATE_INIT;
 282                 static char dummy = '\0';
 283                 Entry *ebase;
 284                 int i;
 285
 286                 op->o_bd->bd_info = (BackendInfo *)dc->dc_on->on_info;
 287                 rc = overlay_entry_get_ov( op, &rs->sr_entry->e_nname, NULL, NULL, 0, &ebase, dc->dc_on );
 288                 if ( rc != LDAP_SUCCESS || ebase == NULL ) {
 289                         op->o_bd->bd_info = bi;
 290                         return SLAP_CB_CONTINUE;
 291                 }
 292
 293                 for ( ds = dc->dc_ds; ds; ds = ds->ds_next ) {
 294                         Attribute *a = attr_find( ebase->e_attrs, ds->ds_derefAttr );
 295
 296                         if ( a != NULL ) {
 297                                 DerefVal *dv;
 298                                 BerVarray *bva;
 299
 300                                 if ( !access_allowed( op, rs->sr_entry, a->a_desc,
 301                                                 NULL, ACL_READ, &acl_state ) )
 302                                 {
 303                                         continue;
 304                                 }
 305
 306                                 dr = op->o_tmpcalloc( 1,
 307                                         sizeof( DerefRes ) + ( sizeof( DerefVal ) + sizeof( BerVarray * ) * ds->ds_nattrs ) * ( a->a_numvals + 1 ),
 308                                         op->o_tmpmemctx );
 309                                 dr->dr_spec = *ds;
 310                                 dv = dr->dr_vals = (DerefVal *)&dr[ 1 ];
 311                                 bva = (BerVarray *)&dv[ a->a_numvals + 1 ];
 312
 313                                 bv.bv_len += ds->ds_derefAttr->ad_cname.bv_len;
 314                                 nAttrs++;
 315                                 nDerefRes++;
 316
 317                                 for ( i = 0; !BER_BVISNULL( &a->a_nvals[ i ] ); i++ ) {
 318                                         Entry *e = NULL;
 319
 320                                         dv[ i ].dv_attrVals = bva;
 321                                         bva += ds->ds_nattrs;
 322
 323
 324                                         if ( !access_allowed( op, rs->sr_entry, a->a_desc,
 325                                                         &a->a_nvals[ i ], ACL_READ, &acl_state ) )
 326                                         {
 327                                                 dv[ i ].dv_derefSpecVal.bv_val = &dummy;
 328                                                 continue;
 329                                         }
 330
 331                                         dv[i].dv_derefSpecVal = a->a_vals[ i ];
 332                                         bv.bv_len += dv[i].dv_derefSpecVal.bv_len;
 333                                         nVals++;
 334                                         nDerefVals++;
 335
 336                                         rc = overlay_entry_get_ov( op, &a->a_nvals[ i ], NULL, NULL, 0, &e, dc->dc_on );
 337                                         if ( rc == LDAP_SUCCESS && e != NULL ) {
 338                                                 int j;
 339
 340                                                 if ( access_allowed( op, e, slap_schema.si_ad_entry,
 341                                                         NULL, ACL_READ, NULL ) )
 342                                                 {
 343                                                         for ( j = 0; j < ds->ds_nattrs; j++ ) {
 344                                                                 Attribute *aa;
 345
 346                                                                 if ( !access_allowed( op, e, ds->ds_attributes[ j ], NULL,
 347                                                                         ACL_READ, &acl_state ) )
 348                                                                 {
 349                                                                         continue;
 350                                                                 }
 351
 352                                                                 aa = attr_find( e->e_attrs, ds->ds_attributes[ j ] );
 353                                                                 if ( aa != NULL ) {
 354                                                                         unsigned k, h, last = aa->a_numvals;
 355
 356                                                                         ber_bvarray_dup_x( &dv[ i ].dv_attrVals[ j ],
 357                                                                                 aa->a_vals, op->o_tmpmemctx );
 358
 359                                                                         bv.bv_len += ds->ds_attributes[ j ]->ad_cname.bv_len;
 360
 361                                                                         for ( k = 0, h = 0; k < aa->a_numvals; k++ ) {
 362                                                                                 if ( !access_allowed( op, e,
 363                                                                                         aa->a_desc,
 364                                                                                         &aa->a_nvals[ k ],
 365                                                                                         ACL_READ, &acl_state ) )
 366                                                                                 {
 367                                                                                         op->o_tmpfree( dv[ i ].dv_attrVals[ j ][ h ].bv_val,
 368                                                                                                 op->o_tmpmemctx );
 369                                                                                         dv[ i ].dv_attrVals[ j ][ h ] = dv[ i ].dv_attrVals[ j ][ --last ];
 370                                                                                         BER_BVZERO( &dv[ i ].dv_attrVals[ j ][ last ] );
 371                                                                                         continue;
 372                                                                                 }
 373                                                                                 bv.bv_len += dv[ i ].dv_attrVals[ j ][ h ].bv_len;
 374                                                                                 nVals++;
 375                                                                                 h++;
 376                                                                         }
 377                                                                         nAttrs++;
 378                                                                 }
 379                                                         }
 380                                                 }
 381
 382                                                 overlay_entry_release_ov( op, e, 0, dc->dc_on );
 383                                         }
 384                                 }
 385
 386                                 *drp = dr;
 387                                 drp = &dr->dr_next;
 388                         }
 389                 }
 390                 overlay_entry_release_ov( op, ebase, 0, dc->dc_on );
 391                 op->o_bd->bd_info = bi;
 392
 393                 if ( drhead == NULL ) {
 394                         return SLAP_CB_CONTINUE;
 395                 }
 396
 397                 /* cook the control value */
 398                 bv.bv_len += nVals * sizeof(struct berval)
 399                         + nAttrs * sizeof(struct berval)
 400                         + nDerefVals * sizeof(DerefVal)
 401                         + nDerefRes * sizeof(DerefRes);
 402                 bv.bv_val = op->o_tmpalloc( bv.bv_len, op->o_tmpmemctx );
 403
 404                 ber_init2( ber, &bv, LBER_USE_DER );
 405                 ber_set_option( ber, LBER_OPT_BER_MEMCTX, &op->o_tmpmemctx );
 406
 407                 rc = ber_printf( ber, "{" /*}*/ );
 408                 for ( dr = drhead; dr != NULL; dr = dr->dr_next ) {
 409                         for ( i = 0; !BER_BVISNULL( &dr->dr_vals[ i ].dv_derefSpecVal ); i++ ) {
 410                                 int j, first = 1;
 411
 412                                 if ( dr->dr_vals[ i ].dv_derefSpecVal.bv_val == &dummy ) {
 413                                         continue;
 414                                 }
 415
 416                                 rc = ber_printf( ber, "{OO" /*}*/,
 417                                         &dr->dr_spec.ds_derefAttr->ad_cname,
 418                                         &dr->dr_vals[ i ].dv_derefSpecVal );
 419                                 for ( j = 0; j < dr->dr_spec.ds_nattrs; j++ ) {
 420                                         if ( dr->dr_vals[ i ].dv_attrVals[ j ] != NULL ) {
 421                                                 if ( first ) {
 422                                                         rc = ber_printf( ber, "t{" /*}*/,
 423                                                                 (LBER_CONSTRUCTED|LBER_CLASS_CONTEXT) );
 424                                                         first = 0;
 425                                                 }
 426                                                 rc = ber_printf( ber, "{O[W]}",
 427                                                         &dr->dr_spec.ds_attributes[ j ]->ad_cname,
 428                                                         dr->dr_vals[ i ].dv_attrVals[ j ] );
 429                                                 op->o_tmpfree( dr->dr_vals[ i ].dv_attrVals[ j ],
 430                                                         op->o_tmpmemctx );
 431                                         }
 432                                 }
 433                                 if ( !first ) {
 434                                         rc = ber_printf( ber, /*{{*/ "}N}" );
 435                                 } else {
 436                                         rc = ber_printf( ber, /*{*/ "}" );
 437                                 }
 438                         }
 439                 }
 440                 rc = ber_printf( ber, /*{*/ "}" );
 441                 if ( ber_flatten2( ber, &ctrlval, 0 ) == -1 ) {
 442                         if ( op->o_deref == SLAP_CONTROL_CRITICAL ) {
 443                                 rc = LDAP_CONSTRAINT_VIOLATION;
 444
 445                         } else {
 446                                 rc = SLAP_CB_CONTINUE;
 447                         }
 448                         goto cleanup;
 449                 }
 450
 451                 ctrl = op->o_tmpcalloc( 1,
 452                         sizeof( LDAPControl ) + ctrlval.bv_len + 1,
 453                         op->o_tmpmemctx );
 454                 ctrl->ldctl_value.bv_val = (char *)&ctrl[ 1 ];
 455                 ctrl->ldctl_oid = LDAP_CONTROL_X_DEREF;
 456                 ctrl->ldctl_iscritical = 0;
 457                 ctrl->ldctl_value.bv_len = ctrlval.bv_len;
 458                 lutil_strncopy( ctrl->ldctl_value.bv_val, ctrlval.bv_val, ctrlval.bv_len );
 459                 ctrl->ldctl_value.bv_val[ ctrl->ldctl_value.bv_len ] = '\0';
 460
 461                 ber_free_buf( ber );
 462
 463                 i = 0;
 464                 if ( rs->sr_ctrls ) {
 465                         for ( ; rs->sr_ctrls[ i ] != NULL; i++ )
 466                                 /* count'em */ ;
 467                 }
 468                 i += 2;
 469                 ctrlsp = op->o_tmpcalloc( i, sizeof(LDAPControl *), op->o_tmpmemctx );
 470                 i = 0;
 471                 if ( rs->sr_ctrls != NULL ) {
 472                         for ( ; rs->sr_ctrls[ i ] != NULL; i++ ) {
 473                                 ctrlsp[ i ] = rs->sr_ctrls[ i ];
 474                         }
 475                 }
 476                 ctrlsp[ i++ ] = ctrl;
 477                 ctrlsp[ i++ ] = NULL;
 478                 if ( rs->sr_flags & REP_CTRLS_MUSTBEFREED ) {
 479                         op->o_tmpfree( rs->sr_ctrls, op->o_tmpmemctx );
 480                 }
 481                 rs->sr_ctrls = ctrlsp;
 482                 rs->sr_flags |= REP_CTRLS_MUSTBEFREED;
 483
 484                 rc = SLAP_CB_CONTINUE;
 485
 486 cleanup:;
 487                 /* release all */
 488                 for ( ; drhead != NULL; ) {
 489                         DerefRes *drnext = drhead->dr_next;
 490                         op->o_tmpfree( drhead, op->o_tmpmemctx );
 491                         drhead = drnext;
 492                 }
 493         }
 494
 495         return rc;
 496 }
 497
 498 static int
 499 deref_cleanup( Operation *op, SlapReply *rs )
 500 {
 501         if ( rs->sr_type == REP_RESULT || rs->sr_err == SLAPD_ABANDON ) {
 502                 op->o_tmpfree( op->o_callback, op->o_tmpmemctx );
 503                 op->o_callback = NULL;
 504
 505                 op->o_tmpfree( op->o_ctrlderef, op->o_tmpmemctx );
 506                 op->o_ctrlderef = NULL;
 507         }
 508
 509         return SLAP_CB_CONTINUE;
 510 }
 511
 512 static int
 513 deref_op_search( Operation *op, SlapReply *rs )
 514 {
 515         if ( op->o_deref ) {
 516                 slap_callback *sc;
 517                 deref_cb_t *dc;
 518
 519                 sc = op->o_tmpcalloc( 1, sizeof( slap_callback ) + sizeof( deref_cb_t ), op->o_tmpmemctx );
 520
 521                 dc = (deref_cb_t *)&sc[ 1 ];
 522                 dc->dc_on = (slap_overinst *)op->o_bd->bd_info;
 523                 dc->dc_ds = (DerefSpec *)op->o_ctrlderef;
 524
 525                 sc->sc_response = deref_response;
 526                 sc->sc_cleanup = deref_cleanup;
 527                 sc->sc_private = (void *)dc;
 528
 529                 sc->sc_next = op->o_callback->sc_next;
 530                 op->o_callback->sc_next = sc;
 531         }
 532
 533         return SLAP_CB_CONTINUE;
 534 }
 535
 536 int
 537 deref_initialize(void)
 538 {
 539         int rc;
 540
 541         rc = register_supported_control( LDAP_CONTROL_X_DEREF,
 542                 SLAP_CTRL_SEARCH, NULL,
 543                 deref_parseCtrl, &deref_cid );
 544         if ( rc != LDAP_SUCCESS ) {
 545                 Debug( LDAP_DEBUG_ANY,
 546                         "deref_init: Failed to register control (%d)\n",
 547                 rc, 0, 0 );
 548                 return -1;
 549         }
 550
 551         deref.on_bi.bi_type = "deref";
 552         deref.on_bi.bi_op_search = deref_op_search;
 553
 554         return overlay_register( &deref );
 555 }
 556
 557 #if SLAPD_OVER_DEREF == SLAPD_MOD_DYNAMIC
 558 int
 559 init_module( int argc, char *argv[] )
 560 {
 561         return deref_initialize();
 562 }
 563 #endif /* SLAPD_OVER_DEREF == SLAPD_MOD_DYNAMIC */
 564
 565 #endif /* SLAPD_OVER_DEREF */