contrib/bind9/lib/dns/ecdb.c

   1 /*
   2  * Copyright (C) 2009-2013  Internet Systems Consortium, Inc. ("ISC")
   3  *
   4  * Permission to use, copy, modify, and/or distribute this software for any
   5  * purpose with or without fee is hereby granted, provided that the above
   6  * copyright notice and this permission notice appear in all copies.
   7  *
   8  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
   9  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
  10  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
  11  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
  12  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
  13  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  14  * PERFORMANCE OF THIS SOFTWARE.
  15  */
  16
  17 /* $Id$ */
  18
  19 #include "config.h"
  20
  21 #include <isc/result.h>
  22 #include <isc/util.h>
  23 #include <isc/mutex.h>
  24 #include <isc/mem.h>
  25
  26 #include <dns/db.h>
  27 #include <dns/ecdb.h>
  28 #include <dns/rdata.h>
  29 #include <dns/rdataset.h>
  30 #include <dns/rdatasetiter.h>
  31 #include <dns/rdataslab.h>
  32
  33 #define ECDB_MAGIC              ISC_MAGIC('E', 'C', 'D', 'B')
  34 #define VALID_ECDB(db)          ((db) != NULL && \
  35                                  (db)->common.impmagic == ECDB_MAGIC)
  36
  37 #define ECDBNODE_MAGIC          ISC_MAGIC('E', 'C', 'D', 'N')
  38 #define VALID_ECDBNODE(ecdbn)   ISC_MAGIC_VALID(ecdbn, ECDBNODE_MAGIC)
  39
  40 /*%
  41  * The 'ephemeral' cache DB (ecdb) implementation.  An ecdb just provides
  42  * temporary storage for ongoing name resolution with the common DB interfaces.
  43  * It actually doesn't cache anything.  The implementation expects any stored
  44  * data is released within a short period, and does not care about the
  45  * scalability in terms of the number of nodes.
  46  */
  47
  48 typedef struct dns_ecdb {
  49         /* Unlocked */
  50         dns_db_t                        common;
  51         isc_mutex_t                     lock;
  52
  53         /* Locked */
  54         unsigned int                    references;
  55         ISC_LIST(struct dns_ecdbnode)   nodes;
  56 } dns_ecdb_t;
  57
  58 typedef struct dns_ecdbnode {
  59         /* Unlocked */
  60         unsigned int                    magic;
  61         isc_mutex_t                     lock;
  62         dns_ecdb_t                      *ecdb;
  63         dns_name_t                      name;
  64         ISC_LINK(struct dns_ecdbnode)   link;
  65
  66         /* Locked */
  67         ISC_LIST(struct rdatasetheader) rdatasets;
  68         unsigned int                    references;
  69 } dns_ecdbnode_t;
  70
  71 typedef struct rdatasetheader {
  72         dns_rdatatype_t                 type;
  73         dns_ttl_t                       ttl;
  74         dns_trust_t                     trust;
  75         dns_rdatatype_t                 covers;
  76         unsigned int                    attributes;
  77
  78         ISC_LINK(struct rdatasetheader) link;
  79 } rdatasetheader_t;
  80
  81 /* Copied from rbtdb.c */
  82 #define RDATASET_ATTR_NXDOMAIN          0x0010
  83 #define RDATASET_ATTR_NEGATIVE          0x0100
  84 #define NXDOMAIN(header) \
  85         (((header)->attributes & RDATASET_ATTR_NXDOMAIN) != 0)
  86 #define NEGATIVE(header) \
  87         (((header)->attributes & RDATASET_ATTR_NEGATIVE) != 0)
  88
  89 static isc_result_t dns_ecdb_create(isc_mem_t *mctx, dns_name_t *origin,
  90                                     dns_dbtype_t type,
  91                                     dns_rdataclass_t rdclass,
  92                                     unsigned int argc, char *argv[],
  93                                     void *driverarg, dns_db_t **dbp);
  94
  95 static void rdataset_disassociate(dns_rdataset_t *rdataset);
  96 static isc_result_t rdataset_first(dns_rdataset_t *rdataset);
  97 static isc_result_t rdataset_next(dns_rdataset_t *rdataset);
  98 static void rdataset_current(dns_rdataset_t *rdataset, dns_rdata_t *rdata);
  99 static void rdataset_clone(dns_rdataset_t *source, dns_rdataset_t *target);
 100 static unsigned int rdataset_count(dns_rdataset_t *rdataset);
 101 static void rdataset_settrust(dns_rdataset_t *rdataset, dns_trust_t trust);
 102
 103 static dns_rdatasetmethods_t rdataset_methods = {
 104         rdataset_disassociate,
 105         rdataset_first,
 106         rdataset_next,
 107         rdataset_current,
 108         rdataset_clone,
 109         rdataset_count,
 110         NULL,                   /* addnoqname */
 111         NULL,                   /* getnoqname */
 112         NULL,                   /* addclosest */
 113         NULL,                   /* getclosest */
 114         NULL,                   /* getadditional */
 115         NULL,                   /* setadditional */
 116         NULL,                   /* putadditional */
 117         rdataset_settrust,      /* settrust */
 118         NULL                    /* expire */
 119 };
 120
 121 typedef struct ecdb_rdatasetiter {
 122         dns_rdatasetiter_t              common;
 123         rdatasetheader_t               *current;
 124 } ecdb_rdatasetiter_t;
 125
 126 static void             rdatasetiter_destroy(dns_rdatasetiter_t **iteratorp);
 127 static isc_result_t     rdatasetiter_first(dns_rdatasetiter_t *iterator);
 128 static isc_result_t     rdatasetiter_next(dns_rdatasetiter_t *iterator);
 129 static void             rdatasetiter_current(dns_rdatasetiter_t *iterator,
 130                                              dns_rdataset_t *rdataset);
 131
 132 static dns_rdatasetitermethods_t rdatasetiter_methods = {
 133         rdatasetiter_destroy,
 134         rdatasetiter_first,
 135         rdatasetiter_next,
 136         rdatasetiter_current
 137 };
 138
 139 isc_result_t
 140 dns_ecdb_register(isc_mem_t *mctx, dns_dbimplementation_t **dbimp) {
 141         REQUIRE(mctx != NULL);
 142         REQUIRE(dbimp != NULL && *dbimp == NULL);
 143
 144         return (dns_db_register("ecdb", dns_ecdb_create, NULL, mctx, dbimp));
 145 }
 146
 147 void
 148 dns_ecdb_unregister(dns_dbimplementation_t **dbimp) {
 149         REQUIRE(dbimp != NULL && *dbimp != NULL);
 150
 151         dns_db_unregister(dbimp);
 152 }
 153
 154 /*%
 155  * DB routines
 156  */
 157
 158 static void
 159 attach(dns_db_t *source, dns_db_t **targetp) {
 160         dns_ecdb_t *ecdb = (dns_ecdb_t *)source;
 161
 162         REQUIRE(VALID_ECDB(ecdb));
 163         REQUIRE(targetp != NULL && *targetp == NULL);
 164
 165         LOCK(&ecdb->lock);
 166         ecdb->references++;
 167         UNLOCK(&ecdb->lock);
 168
 169         *targetp = source;
 170 }
 171
 172 static void
 173 destroy_ecdb(dns_ecdb_t **ecdbp) {
 174         dns_ecdb_t *ecdb = *ecdbp;
 175         isc_mem_t *mctx = ecdb->common.mctx;
 176
 177         if (dns_name_dynamic(&ecdb->common.origin))
 178                 dns_name_free(&ecdb->common.origin, mctx);
 179
 180         DESTROYLOCK(&ecdb->lock);
 181
 182         ecdb->common.impmagic = 0;
 183         ecdb->common.magic = 0;
 184
 185         isc_mem_putanddetach(&mctx, ecdb, sizeof(*ecdb));
 186
 187         *ecdbp = NULL;
 188 }
 189
 190 static void
 191 detach(dns_db_t **dbp) {
 192         dns_ecdb_t *ecdb;
 193         isc_boolean_t need_destroy = ISC_FALSE;
 194
 195         REQUIRE(dbp != NULL);
 196         ecdb = (dns_ecdb_t *)*dbp;
 197         REQUIRE(VALID_ECDB(ecdb));
 198
 199         LOCK(&ecdb->lock);
 200         ecdb->references--;
 201         if (ecdb->references == 0 && ISC_LIST_EMPTY(ecdb->nodes))
 202                 need_destroy = ISC_TRUE;
 203         UNLOCK(&ecdb->lock);
 204
 205         if (need_destroy)
 206                 destroy_ecdb(&ecdb);
 207
 208         *dbp = NULL;
 209 }
 210
 211 static void
 212 attachnode(dns_db_t *db, dns_dbnode_t *source, dns_dbnode_t **targetp) {
 213         dns_ecdb_t *ecdb = (dns_ecdb_t *)db;
 214         dns_ecdbnode_t *node = (dns_ecdbnode_t *)source;
 215
 216         REQUIRE(VALID_ECDB(ecdb));
 217         REQUIRE(VALID_ECDBNODE(node));
 218         REQUIRE(targetp != NULL && *targetp == NULL);
 219
 220         LOCK(&node->lock);
 221         INSIST(node->references > 0);
 222         node->references++;
 223         INSIST(node->references != 0);          /* Catch overflow. */
 224         UNLOCK(&node->lock);
 225
 226         *targetp = node;
 227 }
 228
 229 static void
 230 destroynode(dns_ecdbnode_t *node) {
 231         isc_mem_t *mctx;
 232         dns_ecdb_t *ecdb = node->ecdb;
 233         isc_boolean_t need_destroydb = ISC_FALSE;
 234         rdatasetheader_t *header;
 235
 236         mctx = ecdb->common.mctx;
 237
 238         LOCK(&ecdb->lock);
 239         ISC_LIST_UNLINK(ecdb->nodes, node, link);
 240         if (ecdb->references == 0 && ISC_LIST_EMPTY(ecdb->nodes))
 241                 need_destroydb = ISC_TRUE;
 242         UNLOCK(&ecdb->lock);
 243
 244         dns_name_free(&node->name, mctx);
 245
 246         while ((header = ISC_LIST_HEAD(node->rdatasets)) != NULL) {
 247                 unsigned int headersize;
 248
 249                 ISC_LIST_UNLINK(node->rdatasets, header, link);
 250                 headersize =
 251                         dns_rdataslab_size((unsigned char *)header,
 252                                            sizeof(*header));
 253                 isc_mem_put(mctx, header, headersize);
 254         }
 255
 256         DESTROYLOCK(&node->lock);
 257
 258         node->magic = 0;
 259         isc_mem_put(mctx, node, sizeof(*node));
 260
 261         if (need_destroydb)
 262                 destroy_ecdb(&ecdb);
 263 }
 264
 265 static void
 266 detachnode(dns_db_t *db, dns_dbnode_t **nodep) {
 267         dns_ecdb_t *ecdb = (dns_ecdb_t *)db;
 268         dns_ecdbnode_t *node;
 269         isc_boolean_t need_destroy = ISC_FALSE;
 270
 271         REQUIRE(VALID_ECDB(ecdb));
 272         REQUIRE(nodep != NULL);
 273         node = (dns_ecdbnode_t *)*nodep;
 274         REQUIRE(VALID_ECDBNODE(node));
 275
 276         UNUSED(ecdb);           /* in case REQUIRE() is empty */
 277
 278         LOCK(&node->lock);
 279         INSIST(node->references > 0);
 280         node->references--;
 281         if (node->references == 0)
 282                 need_destroy = ISC_TRUE;
 283         UNLOCK(&node->lock);
 284
 285         if (need_destroy)
 286                 destroynode(node);
 287
 288         *nodep = NULL;
 289 }
 290
 291 static isc_result_t
 292 find(dns_db_t *db, dns_name_t *name, dns_dbversion_t *version,
 293     dns_rdatatype_t type, unsigned int options, isc_stdtime_t now,
 294     dns_dbnode_t **nodep, dns_name_t *foundname, dns_rdataset_t *rdataset,
 295     dns_rdataset_t *sigrdataset)
 296 {
 297         dns_ecdb_t *ecdb = (dns_ecdb_t *)db;
 298
 299         REQUIRE(VALID_ECDB(ecdb));
 300
 301         UNUSED(name);
 302         UNUSED(version);
 303         UNUSED(type);
 304         UNUSED(options);
 305         UNUSED(now);
 306         UNUSED(nodep);
 307         UNUSED(foundname);
 308         UNUSED(rdataset);
 309         UNUSED(sigrdataset);
 310
 311         return (ISC_R_NOTFOUND);
 312 }
 313
 314 static isc_result_t
 315 findzonecut(dns_db_t *db, dns_name_t *name,
 316             unsigned int options, isc_stdtime_t now,
 317             dns_dbnode_t **nodep, dns_name_t *foundname,
 318             dns_rdataset_t *rdataset, dns_rdataset_t *sigrdataset)
 319 {
 320         dns_ecdb_t *ecdb = (dns_ecdb_t *)db;
 321
 322         REQUIRE(VALID_ECDB(ecdb));
 323
 324         UNUSED(name);
 325         UNUSED(options);
 326         UNUSED(now);
 327         UNUSED(nodep);
 328         UNUSED(foundname);
 329         UNUSED(rdataset);
 330         UNUSED(sigrdataset);
 331
 332         return (ISC_R_NOTFOUND);
 333 }
 334
 335 static isc_result_t
 336 findnode(dns_db_t *db, dns_name_t *name, isc_boolean_t create,
 337          dns_dbnode_t **nodep)
 338 {
 339         dns_ecdb_t *ecdb = (dns_ecdb_t *)db;
 340         isc_mem_t *mctx;
 341         dns_ecdbnode_t *node;
 342         isc_result_t result;
 343
 344         REQUIRE(VALID_ECDB(ecdb));
 345         REQUIRE(nodep != NULL && *nodep == NULL);
 346
 347         UNUSED(name);
 348
 349         if (create != ISC_TRUE) {
 350                 /* an 'ephemeral' node is never reused. */
 351                 return (ISC_R_NOTFOUND);
 352         }
 353
 354         mctx = ecdb->common.mctx;
 355         node = isc_mem_get(mctx, sizeof(*node));
 356         if (node == NULL)
 357                 return (ISC_R_NOMEMORY);
 358
 359         result = isc_mutex_init(&node->lock);
 360         if (result != ISC_R_SUCCESS) {
 361                 UNEXPECTED_ERROR(__FILE__, __LINE__,
 362                                  "isc_mutex_init() failed: %s",
 363                                  isc_result_totext(result));
 364                 isc_mem_put(mctx, node, sizeof(*node));
 365                 return (ISC_R_UNEXPECTED);
 366         }
 367
 368         dns_name_init(&node->name, NULL);
 369         result = dns_name_dup(name, mctx, &node->name);
 370         if (result != ISC_R_SUCCESS) {
 371                 DESTROYLOCK(&node->lock);
 372                 isc_mem_put(mctx, node, sizeof(*node));
 373                 return (result);
 374         }
 375         node->ecdb= ecdb;
 376         node->references = 1;
 377         ISC_LIST_INIT(node->rdatasets);
 378
 379         ISC_LINK_INIT(node, link);
 380
 381         LOCK(&ecdb->lock);
 382         ISC_LIST_APPEND(ecdb->nodes, node, link);
 383         UNLOCK(&ecdb->lock);
 384
 385         node->magic = ECDBNODE_MAGIC;
 386
 387         *nodep = node;
 388
 389         return (ISC_R_SUCCESS);
 390 }
 391
 392 static void
 393 bind_rdataset(dns_ecdb_t *ecdb, dns_ecdbnode_t *node,
 394               rdatasetheader_t *header, dns_rdataset_t *rdataset)
 395 {
 396         unsigned char *raw;
 397
 398         /*
 399          * Caller must be holding the node lock.
 400          */
 401
 402         REQUIRE(!dns_rdataset_isassociated(rdataset));
 403
 404         rdataset->methods = &rdataset_methods;
 405         rdataset->rdclass = ecdb->common.rdclass;
 406         rdataset->type = header->type;
 407         rdataset->covers = header->covers;
 408         rdataset->ttl = header->ttl;
 409         rdataset->trust = header->trust;
 410         if (NXDOMAIN(header))
 411                 rdataset->attributes |= DNS_RDATASETATTR_NXDOMAIN;
 412         if (NEGATIVE(header))
 413                 rdataset->attributes |= DNS_RDATASETATTR_NEGATIVE;
 414
 415         rdataset->private1 = ecdb;
 416         rdataset->private2 = node;
 417         raw = (unsigned char *)header + sizeof(*header);
 418         rdataset->private3 = raw;
 419         rdataset->count = 0;
 420
 421         /*
 422          * Reset iterator state.
 423          */
 424         rdataset->privateuint4 = 0;
 425         rdataset->private5 = NULL;
 426
 427         INSIST(node->references > 0);
 428         node->references++;
 429 }
 430
 431 static isc_result_t
 432 addrdataset(dns_db_t *db, dns_dbnode_t *node, dns_dbversion_t *version,
 433             isc_stdtime_t now, dns_rdataset_t *rdataset, unsigned int options,
 434             dns_rdataset_t *addedrdataset)
 435 {
 436         dns_ecdb_t *ecdb = (dns_ecdb_t *)db;
 437         isc_region_t r;
 438         isc_result_t result = ISC_R_SUCCESS;
 439         isc_mem_t *mctx;
 440         dns_ecdbnode_t *ecdbnode = (dns_ecdbnode_t *)node;
 441         rdatasetheader_t *header;
 442
 443         REQUIRE(VALID_ECDB(ecdb));
 444         REQUIRE(VALID_ECDBNODE(ecdbnode));
 445
 446         UNUSED(version);
 447         UNUSED(now);
 448         UNUSED(options);
 449
 450         mctx = ecdb->common.mctx;
 451
 452         LOCK(&ecdbnode->lock);
 453
 454         /*
 455          * Sanity check: this implementation does not allow overriding an
 456          * existing rdataset of the same type.
 457          */
 458         for (header = ISC_LIST_HEAD(ecdbnode->rdatasets); header != NULL;
 459              header = ISC_LIST_NEXT(header, link)) {
 460                 INSIST(header->type != rdataset->type ||
 461                        header->covers != rdataset->covers);
 462         }
 463
 464         result = dns_rdataslab_fromrdataset(rdataset, mctx,
 465                                             &r, sizeof(rdatasetheader_t));
 466         if (result != ISC_R_SUCCESS)
 467                 goto unlock;
 468
 469         header = (rdatasetheader_t *)r.base;
 470         header->type = rdataset->type;
 471         header->ttl = rdataset->ttl;
 472         header->trust = rdataset->trust;
 473         header->covers = rdataset->covers;
 474         header->attributes = 0;
 475         if ((rdataset->attributes & DNS_RDATASETATTR_NXDOMAIN) != 0)
 476                 header->attributes |= RDATASET_ATTR_NXDOMAIN;
 477         if ((rdataset->attributes & DNS_RDATASETATTR_NEGATIVE) != 0)
 478                 header->attributes |= RDATASET_ATTR_NEGATIVE;
 479         ISC_LINK_INIT(header, link);
 480         ISC_LIST_APPEND(ecdbnode->rdatasets, header, link);
 481
 482         if (addedrdataset == NULL)
 483                 goto unlock;
 484
 485         bind_rdataset(ecdb, ecdbnode, header, addedrdataset);
 486
 487  unlock:
 488         UNLOCK(&ecdbnode->lock);
 489
 490         return (result);
 491 }
 492
 493 static isc_result_t
 494 deleterdataset(dns_db_t *db, dns_dbnode_t *node, dns_dbversion_t *version,
 495                dns_rdatatype_t type, dns_rdatatype_t covers)
 496 {
 497         UNUSED(db);
 498         UNUSED(node);
 499         UNUSED(version);
 500         UNUSED(type);
 501         UNUSED(covers);
 502
 503         return (ISC_R_NOTIMPLEMENTED);
 504 }
 505
 506 static isc_result_t
 507 createiterator(dns_db_t *db, unsigned int options,
 508                dns_dbiterator_t **iteratorp)
 509 {
 510         UNUSED(db);
 511         UNUSED(options);
 512         UNUSED(iteratorp);
 513
 514         return (ISC_R_NOTIMPLEMENTED);
 515 }
 516
 517 static isc_result_t
 518 allrdatasets(dns_db_t *db, dns_dbnode_t *node, dns_dbversion_t *version,
 519              isc_stdtime_t now, dns_rdatasetiter_t **iteratorp)
 520 {
 521         dns_ecdb_t *ecdb = (dns_ecdb_t *)db;
 522         dns_ecdbnode_t *ecdbnode = (dns_ecdbnode_t *)node;
 523         isc_mem_t *mctx;
 524         ecdb_rdatasetiter_t *iterator;
 525
 526         REQUIRE(VALID_ECDB(ecdb));
 527         REQUIRE(VALID_ECDBNODE(ecdbnode));
 528
 529         mctx = ecdb->common.mctx;
 530
 531         iterator = isc_mem_get(mctx, sizeof(ecdb_rdatasetiter_t));
 532         if (iterator == NULL)
 533                 return (ISC_R_NOMEMORY);
 534
 535         iterator->common.magic = DNS_RDATASETITER_MAGIC;
 536         iterator->common.methods = &rdatasetiter_methods;
 537         iterator->common.db = db;
 538         iterator->common.node = NULL;
 539         attachnode(db, node, &iterator->common.node);
 540         iterator->common.version = version;
 541         iterator->common.now = now;
 542
 543         *iteratorp = (dns_rdatasetiter_t *)iterator;
 544
 545         return (ISC_R_SUCCESS);
 546 }
 547
 548 static dns_dbmethods_t ecdb_methods = {
 549         attach,
 550         detach,
 551         NULL,                   /* beginload */
 552         NULL,                   /* endload */
 553         NULL,                   /* dump */
 554         NULL,                   /* currentversion */
 555         NULL,                   /* newversion */
 556         NULL,                   /* attachversion */
 557         NULL,                   /* closeversion */
 558         findnode,
 559         find,
 560         findzonecut,
 561         attachnode,
 562         detachnode,
 563         NULL,                   /* expirenode */
 564         NULL,                   /* printnode */
 565         createiterator,         /* createiterator */
 566         NULL,                   /* findrdataset */
 567         allrdatasets,
 568         addrdataset,
 569         NULL,                   /* subtractrdataset */
 570         deleterdataset,
 571         NULL,                   /* issecure */
 572         NULL,                   /* nodecount */
 573         NULL,                   /* ispersistent */
 574         NULL,                   /* overmem */
 575         NULL,                   /* settask */
 576         NULL,                   /* getoriginnode */
 577         NULL,                   /* transfernode */
 578         NULL,                   /* getnsec3parameters */
 579         NULL,                   /* findnsec3node */
 580         NULL,                   /* setsigningtime */
 581         NULL,                   /* getsigningtime */
 582         NULL,                   /* resigned */
 583         NULL,                   /* isdnssec */
 584         NULL,                   /* getrrsetstats */
 585         NULL,                   /* rpz_enabled */
 586         NULL                    /* rpz_findips */
 587 };
 588
 589 static isc_result_t
 590 dns_ecdb_create(isc_mem_t *mctx, dns_name_t *origin, dns_dbtype_t type,
 591                 dns_rdataclass_t rdclass, unsigned int argc, char *argv[],
 592                 void *driverarg, dns_db_t **dbp)
 593 {
 594         dns_ecdb_t *ecdb;
 595         isc_result_t result;
 596
 597         REQUIRE(mctx != NULL);
 598         REQUIRE(origin == dns_rootname);
 599         REQUIRE(type == dns_dbtype_cache);
 600         REQUIRE(dbp != NULL && *dbp == NULL);
 601
 602         UNUSED(argc);
 603         UNUSED(argv);
 604         UNUSED(driverarg);
 605
 606         ecdb = isc_mem_get(mctx, sizeof(*ecdb));
 607         if (ecdb == NULL)
 608                 return (ISC_R_NOMEMORY);
 609
 610         ecdb->common.attributes = DNS_DBATTR_CACHE;
 611         ecdb->common.rdclass = rdclass;
 612         ecdb->common.methods = &ecdb_methods;
 613         dns_name_init(&ecdb->common.origin, NULL);
 614         result = dns_name_dupwithoffsets(origin, mctx, &ecdb->common.origin);
 615         if (result != ISC_R_SUCCESS) {
 616                 isc_mem_put(mctx, ecdb, sizeof(*ecdb));
 617                 return (result);
 618         }
 619
 620         result = isc_mutex_init(&ecdb->lock);
 621         if (result != ISC_R_SUCCESS) {
 622                 UNEXPECTED_ERROR(__FILE__, __LINE__,
 623                                  "isc_mutex_init() failed: %s",
 624                                  isc_result_totext(result));
 625                 if (dns_name_dynamic(&ecdb->common.origin))
 626                         dns_name_free(&ecdb->common.origin, mctx);
 627                 isc_mem_put(mctx, ecdb, sizeof(*ecdb));
 628                 return (ISC_R_UNEXPECTED);
 629         }
 630
 631         ecdb->references = 1;
 632         ISC_LIST_INIT(ecdb->nodes);
 633
 634         ecdb->common.mctx = NULL;
 635         isc_mem_attach(mctx, &ecdb->common.mctx);
 636         ecdb->common.impmagic = ECDB_MAGIC;
 637         ecdb->common.magic = DNS_DB_MAGIC;
 638
 639         *dbp = (dns_db_t *)ecdb;
 640
 641         return (ISC_R_SUCCESS);
 642 }
 643
 644 /*%
 645  * Rdataset Methods
 646  */
 647
 648 static void
 649 rdataset_disassociate(dns_rdataset_t *rdataset) {
 650         dns_db_t *db = rdataset->private1;
 651         dns_dbnode_t *node = rdataset->private2;
 652
 653         dns_db_detachnode(db, &node);
 654 }
 655
 656 static isc_result_t
 657 rdataset_first(dns_rdataset_t *rdataset) {
 658         unsigned char *raw = rdataset->private3;
 659         unsigned int count;
 660
 661         count = raw[0] * 256 + raw[1];
 662         if (count == 0) {
 663                 rdataset->private5 = NULL;
 664                 return (ISC_R_NOMORE);
 665         }
 666 #if DNS_RDATASET_FIXED
 667         raw += 2 + (4 * count);
 668 #else
 669         raw += 2;
 670 #endif
 671         /*
 672          * The privateuint4 field is the number of rdata beyond the cursor
 673          * position, so we decrement the total count by one before storing
 674          * it.
 675          */
 676         count--;
 677         rdataset->privateuint4 = count;
 678         rdataset->private5 = raw;
 679
 680         return (ISC_R_SUCCESS);
 681 }
 682
 683 static isc_result_t
 684 rdataset_next(dns_rdataset_t *rdataset) {
 685         unsigned int count;
 686         unsigned int length;
 687         unsigned char *raw;
 688
 689         count = rdataset->privateuint4;
 690         if (count == 0)
 691                 return (ISC_R_NOMORE);
 692         count--;
 693         rdataset->privateuint4 = count;
 694         raw = rdataset->private5;
 695         length = raw[0] * 256 + raw[1];
 696 #if DNS_RDATASET_FIXED
 697         raw += length + 4;
 698 #else
 699         raw += length + 2;
 700 #endif
 701         rdataset->private5 = raw;
 702
 703         return (ISC_R_SUCCESS);
 704 }
 705
 706 static void
 707 rdataset_current(dns_rdataset_t *rdataset, dns_rdata_t *rdata) {
 708         unsigned char *raw = rdataset->private5;
 709         isc_region_t r;
 710         unsigned int length;
 711         unsigned int flags = 0;
 712
 713         REQUIRE(raw != NULL);
 714
 715         length = raw[0] * 256 + raw[1];
 716 #if DNS_RDATASET_FIXED
 717         raw += 4;
 718 #else
 719         raw += 2;
 720 #endif
 721         if (rdataset->type == dns_rdatatype_rrsig) {
 722                 if (*raw & DNS_RDATASLAB_OFFLINE)
 723                         flags |= DNS_RDATA_OFFLINE;
 724                 length--;
 725                 raw++;
 726         }
 727         r.length = length;
 728         r.base = raw;
 729         dns_rdata_fromregion(rdata, rdataset->rdclass, rdataset->type, &r);
 730         rdata->flags |= flags;
 731 }
 732
 733 static void
 734 rdataset_clone(dns_rdataset_t *source, dns_rdataset_t *target) {
 735         dns_db_t *db = source->private1;
 736         dns_dbnode_t *node = source->private2;
 737         dns_dbnode_t *cloned_node = NULL;
 738
 739         attachnode(db, node, &cloned_node);
 740         *target = *source;
 741
 742         /*
 743          * Reset iterator state.
 744          */
 745         target->privateuint4 = 0;
 746         target->private5 = NULL;
 747 }
 748
 749 static unsigned int
 750 rdataset_count(dns_rdataset_t *rdataset) {
 751         unsigned char *raw = rdataset->private3;
 752         unsigned int count;
 753
 754         count = raw[0] * 256 + raw[1];
 755
 756         return (count);
 757 }
 758
 759 static void
 760 rdataset_settrust(dns_rdataset_t *rdataset, dns_trust_t trust) {
 761         rdatasetheader_t *header = rdataset->private3;
 762
 763         header--;
 764         header->trust = rdataset->trust = trust;
 765 }
 766
 767 /*
 768  * Rdataset Iterator Methods
 769  */
 770
 771 static void
 772 rdatasetiter_destroy(dns_rdatasetiter_t **iteratorp) {
 773         ecdb_rdatasetiter_t *ecdbiterator;
 774         isc_mem_t *mctx;
 775
 776         REQUIRE(iteratorp != NULL);
 777         ecdbiterator = (ecdb_rdatasetiter_t *)*iteratorp;
 778         REQUIRE(DNS_RDATASETITER_VALID(&ecdbiterator->common));
 779
 780         mctx = ecdbiterator->common.db->mctx;
 781
 782         ecdbiterator->common.magic = 0;
 783
 784         dns_db_detachnode(ecdbiterator->common.db, &ecdbiterator->common.node);
 785         isc_mem_put(mctx, ecdbiterator, sizeof(ecdb_rdatasetiter_t));
 786
 787         *iteratorp = NULL;
 788 }
 789
 790 static isc_result_t
 791 rdatasetiter_first(dns_rdatasetiter_t *iterator) {
 792         ecdb_rdatasetiter_t *ecdbiterator = (ecdb_rdatasetiter_t *)iterator;
 793         dns_ecdbnode_t *ecdbnode = (dns_ecdbnode_t *)iterator->node;
 794
 795         REQUIRE(DNS_RDATASETITER_VALID(iterator));
 796
 797         if (ISC_LIST_EMPTY(ecdbnode->rdatasets))
 798                 return (ISC_R_NOMORE);
 799         ecdbiterator->current = ISC_LIST_HEAD(ecdbnode->rdatasets);
 800         return (ISC_R_SUCCESS);
 801 }
 802
 803 static isc_result_t
 804 rdatasetiter_next(dns_rdatasetiter_t *iterator) {
 805         ecdb_rdatasetiter_t *ecdbiterator = (ecdb_rdatasetiter_t *)iterator;
 806
 807         REQUIRE(DNS_RDATASETITER_VALID(iterator));
 808
 809         ecdbiterator->current = ISC_LIST_NEXT(ecdbiterator->current, link);
 810         if (ecdbiterator->current == NULL)
 811                 return (ISC_R_NOMORE);
 812         else
 813                 return (ISC_R_SUCCESS);
 814 }
 815
 816 static void
 817 rdatasetiter_current(dns_rdatasetiter_t *iterator, dns_rdataset_t *rdataset) {
 818         ecdb_rdatasetiter_t *ecdbiterator = (ecdb_rdatasetiter_t *)iterator;
 819         dns_ecdb_t *ecdb;
 820
 821         ecdb = (dns_ecdb_t *)iterator->db;
 822         REQUIRE(VALID_ECDB(ecdb));
 823
 824         bind_rdataset(ecdb, iterator->node, ecdbiterator->current, rdataset);
 825 }