contrib/bind-9.3/bin/named/update.c

   1 /*
   2  * Copyright (C) 2004, 2005  Internet Systems Consortium, Inc. ("ISC")
   3  * Copyright (C) 1999-2003  Internet Software Consortium.
   4  *
   5  * Permission to use, copy, modify, and distribute this software for any
   6  * purpose with or without fee is hereby granted, provided that the above
   7  * copyright notice and this permission notice appear in all copies.
   8  *
   9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
  10  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
  11  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
  12  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
  13  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
  14  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  15  * PERFORMANCE OF THIS SOFTWARE.
  16  */
  17
  18 /* $Id: update.c,v 1.88.2.5.2.27 2005/10/08 00:21:06 marka Exp $ */
  19
  20 #include <config.h>
  21
  22 #include <isc/print.h>
  23 #include <isc/string.h>
  24 #include <isc/taskpool.h>
  25 #include <isc/util.h>
  26
  27 #include <dns/db.h>
  28 #include <dns/dbiterator.h>
  29 #include <dns/diff.h>
  30 #include <dns/dnssec.h>
  31 #include <dns/events.h>
  32 #include <dns/fixedname.h>
  33 #include <dns/journal.h>
  34 #include <dns/message.h>
  35 #include <dns/nsec.h>
  36 #include <dns/rdataclass.h>
  37 #include <dns/rdataset.h>
  38 #include <dns/rdatasetiter.h>
  39 #include <dns/rdatatype.h>
  40 #include <dns/soa.h>
  41 #include <dns/ssu.h>
  42 #include <dns/view.h>
  43 #include <dns/zone.h>
  44 #include <dns/zt.h>
  45
  46 #include <named/client.h>
  47 #include <named/log.h>
  48 #include <named/update.h>
  49
  50 /*
  51  * This module implements dynamic update as in RFC2136.
  52  */
  53
  54 /*
  55   XXX TODO:
  56   - document strict minimality
  57 */
  58
  59 /**************************************************************************/
  60
  61 /*
  62  * Log level for tracing dynamic update protocol requests.
  63  */
  64 #define LOGLEVEL_PROTOCOL       ISC_LOG_INFO
  65
  66 /*
  67  * Log level for low-level debug tracing.
  68  */
  69 #define LOGLEVEL_DEBUG          ISC_LOG_DEBUG(8)
  70
  71 /*
  72  * Check an operation for failure.  These macros all assume that
  73  * the function using them has a 'result' variable and a 'failure'
  74  * label.
  75  */
  76 #define CHECK(op) \
  77         do { result = (op);                                      \
  78                if (result != ISC_R_SUCCESS) goto failure;        \
  79         } while (0)
  80
  81 /*
  82  * Fail unconditionally with result 'code', which must not
  83  * be ISC_R_SUCCESS.  The reason for failure presumably has
  84  * been logged already.
  85  *
  86  * The test against ISC_R_SUCCESS is there to keep the Solaris compiler
  87  * from complaining about "end-of-loop code not reached".
  88  */
  89
  90 #define FAIL(code) \
  91         do {                                                    \
  92                 result = (code);                                \
  93                 if (result != ISC_R_SUCCESS) goto failure;      \
  94         } while (0)
  95
  96 /*
  97  * Fail unconditionally and log as a client error.
  98  * The test against ISC_R_SUCCESS is there to keep the Solaris compiler
  99  * from complaining about "end-of-loop code not reached".
 100  */
 101 #define FAILC(code, msg) \
 102         do {                                                    \
 103                 const char *_what = "failed";                   \
 104                 result = (code);                                \
 105                 switch (result) {                               \
 106                 case DNS_R_NXDOMAIN:                            \
 107                 case DNS_R_YXDOMAIN:                            \
 108                 case DNS_R_YXRRSET:                             \
 109                 case DNS_R_NXRRSET:                             \
 110                         _what = "unsuccessful";                 \
 111                 }                                               \
 112                 update_log(client, zone, LOGLEVEL_PROTOCOL,     \
 113                               "update %s: %s (%s)", _what,      \
 114                               msg, isc_result_totext(result));  \
 115                 if (result != ISC_R_SUCCESS) goto failure;      \
 116         } while (0)
 117
 118 #define FAILN(code, name, msg) \
 119         do {                                                            \
 120                 const char *_what = "failed";                           \
 121                 result = (code);                                        \
 122                 switch (result) {                                       \
 123                 case DNS_R_NXDOMAIN:                                    \
 124                 case DNS_R_YXDOMAIN:                                    \
 125                 case DNS_R_YXRRSET:                                     \
 126                 case DNS_R_NXRRSET:                                     \
 127                         _what = "unsuccessful";                         \
 128                 }                                                       \
 129                 if (isc_log_wouldlog(ns_g_lctx, LOGLEVEL_PROTOCOL)) {   \
 130                         char _nbuf[DNS_NAME_FORMATSIZE];                \
 131                         dns_name_format(name, _nbuf, sizeof(_nbuf));    \
 132                         update_log(client, zone, LOGLEVEL_PROTOCOL,     \
 133                                    "update %s: %s: %s (%s)", _what, _nbuf, \
 134                                    msg, isc_result_totext(result));     \
 135                 }                                                       \
 136                 if (result != ISC_R_SUCCESS) goto failure;              \
 137         } while (0)
 138
 139 #define FAILNT(code, name, type, msg) \
 140         do {                                                            \
 141                 const char *_what = "failed";                           \
 142                 result = (code);                                        \
 143                 switch (result) {                                       \
 144                 case DNS_R_NXDOMAIN:                                    \
 145                 case DNS_R_YXDOMAIN:                                    \
 146                 case DNS_R_YXRRSET:                                     \
 147                 case DNS_R_NXRRSET:                                     \
 148                         _what = "unsuccessful";                         \
 149                 }                                                       \
 150                 if (isc_log_wouldlog(ns_g_lctx, LOGLEVEL_PROTOCOL)) {   \
 151                         char _nbuf[DNS_NAME_FORMATSIZE];                \
 152                         char _tbuf[DNS_RDATATYPE_FORMATSIZE];           \
 153                         dns_name_format(name, _nbuf, sizeof(_nbuf));    \
 154                         dns_rdatatype_format(type, _tbuf, sizeof(_tbuf)); \
 155                         update_log(client, zone, LOGLEVEL_PROTOCOL,     \
 156                                    "update %s: %s/%s: %s (%s)",         \
 157                                    _what, _nbuf, _tbuf, msg,            \
 158                                    isc_result_totext(result));          \
 159                 }                                                       \
 160                 if (result != ISC_R_SUCCESS) goto failure;              \
 161         } while (0)
 162 /*
 163  * Fail unconditionally and log as a server error.
 164  * The test against ISC_R_SUCCESS is there to keep the Solaris compiler
 165  * from complaining about "end-of-loop code not reached".
 166  */
 167 #define FAILS(code, msg) \
 168         do {                                                    \
 169                 result = (code);                                \
 170                 update_log(client, zone, LOGLEVEL_PROTOCOL,     \
 171                               "error: %s: %s",                  \
 172                               msg, isc_result_totext(result));  \
 173                 if (result != ISC_R_SUCCESS) goto failure;      \
 174         } while (0)
 175
 176 /**************************************************************************/
 177
 178 typedef struct rr rr_t;
 179
 180 struct rr {
 181         /* dns_name_t name; */
 182         isc_uint32_t            ttl;
 183         dns_rdata_t             rdata;
 184 };
 185
 186 typedef struct update_event update_event_t;
 187
 188 struct update_event {
 189         ISC_EVENT_COMMON(update_event_t);
 190         dns_zone_t              *zone;
 191         isc_result_t            result;
 192         dns_message_t           *answer;
 193 };
 194
 195 /**************************************************************************/
 196 /*
 197  * Forward declarations.
 198  */
 199
 200 static void update_action(isc_task_t *task, isc_event_t *event);
 201 static void updatedone_action(isc_task_t *task, isc_event_t *event);
 202 static isc_result_t send_forward_event(ns_client_t *client, dns_zone_t *zone);
 203 static void forward_done(isc_task_t *task, isc_event_t *event);
 204
 205 /**************************************************************************/
 206
 207 static void
 208 update_log(ns_client_t *client, dns_zone_t *zone,
 209            int level, const char *fmt, ...) ISC_FORMAT_PRINTF(4, 5);
 210
 211 static void
 212 update_log(ns_client_t *client, dns_zone_t *zone,
 213            int level, const char *fmt, ...)
 214 {
 215         va_list ap;
 216         char message[4096];
 217         char namebuf[DNS_NAME_FORMATSIZE];
 218         char classbuf[DNS_RDATACLASS_FORMATSIZE];
 219
 220         if (client == NULL || zone == NULL)
 221                 return;
 222
 223         if (isc_log_wouldlog(ns_g_lctx, level) == ISC_FALSE)
 224                 return;
 225
 226         dns_name_format(dns_zone_getorigin(zone), namebuf,
 227                         sizeof(namebuf));
 228         dns_rdataclass_format(dns_zone_getclass(zone), classbuf,
 229                               sizeof(classbuf));
 230
 231         va_start(ap, fmt);
 232         vsnprintf(message, sizeof(message), fmt, ap);
 233         va_end(ap);
 234
 235         ns_client_log(client, NS_LOGCATEGORY_UPDATE, NS_LOGMODULE_UPDATE,
 236                       level, "updating zone '%s/%s': %s",
 237                       namebuf, classbuf, message);
 238 }
 239
 240 static isc_result_t
 241 checkupdateacl(ns_client_t *client, dns_acl_t *acl, const char *message,
 242                dns_name_t *zonename, isc_boolean_t slave)
 243 {
 244         char namebuf[DNS_NAME_FORMATSIZE];
 245         char classbuf[DNS_RDATACLASS_FORMATSIZE];
 246         int level = ISC_LOG_ERROR;
 247         const char *msg = "denied";
 248         isc_result_t result;
 249
 250         if (slave && acl == NULL) {
 251                 result = DNS_R_NOTIMP;
 252                 level = ISC_LOG_DEBUG(3);
 253                 msg = "disabled";
 254         } else
 255                 result = ns_client_checkaclsilent(client, acl, ISC_FALSE);
 256
 257         if (result == ISC_R_SUCCESS) {
 258                 level = ISC_LOG_DEBUG(3);
 259                 msg = "approved";
 260         }
 261
 262         dns_name_format(zonename, namebuf, sizeof(namebuf));
 263         dns_rdataclass_format(client->view->rdclass, classbuf,
 264                               sizeof(classbuf));
 265
 266         ns_client_log(client, NS_LOGCATEGORY_UPDATE_SECURITY,
 267                               NS_LOGMODULE_UPDATE, level, "%s '%s/%s' %s",
 268                               message, namebuf, classbuf, msg);
 269         return (result);
 270 }
 271
 272 /*
 273  * Update a single RR in version 'ver' of 'db' and log the
 274  * update in 'diff'.
 275  *
 276  * Ensures:
 277  *   '*tuple' == NULL.  Either the tuple is freed, or its
 278  *         ownership has been transferred to the diff.
 279  */
 280 static isc_result_t
 281 do_one_tuple(dns_difftuple_t **tuple,
 282              dns_db_t *db, dns_dbversion_t *ver,
 283              dns_diff_t *diff)
 284 {
 285         dns_diff_t temp_diff;
 286         isc_result_t result;
 287
 288         /*
 289          * Create a singleton diff.
 290          */
 291         dns_diff_init(diff->mctx, &temp_diff);
 292         ISC_LIST_APPEND(temp_diff.tuples, *tuple, link);
 293
 294         /*
 295          * Apply it to the database.
 296          */
 297         result = dns_diff_apply(&temp_diff, db, ver);
 298         ISC_LIST_UNLINK(temp_diff.tuples, *tuple, link);
 299         if (result != ISC_R_SUCCESS) {
 300                 dns_difftuple_free(tuple);
 301                 return (result);
 302         }
 303
 304         /*
 305          * Merge it into the current pending journal entry.
 306          */
 307         dns_diff_appendminimal(diff, tuple);
 308
 309         /*
 310          * Do not clear temp_diff.
 311          */
 312         return (ISC_R_SUCCESS);
 313 }
 314
 315 /*
 316  * Perform the updates in 'updates' in version 'ver' of 'db' and log the
 317  * update in 'diff'.
 318  *
 319  * Ensures:
 320  *   'updates' is empty.
 321  */
 322 static isc_result_t
 323 do_diff(dns_diff_t *updates, dns_db_t *db, dns_dbversion_t *ver,
 324         dns_diff_t *diff)
 325 {
 326         isc_result_t result;
 327         while (! ISC_LIST_EMPTY(updates->tuples)) {
 328                 dns_difftuple_t *t = ISC_LIST_HEAD(updates->tuples);
 329                 ISC_LIST_UNLINK(updates->tuples, t, link);
 330                 CHECK(do_one_tuple(&t, db, ver, diff));
 331         }
 332         return (ISC_R_SUCCESS);
 333
 334  failure:
 335         dns_diff_clear(diff);
 336         return (result);
 337 }
 338
 339 static isc_result_t
 340 update_one_rr(dns_db_t *db, dns_dbversion_t *ver, dns_diff_t *diff,
 341               dns_diffop_t op, dns_name_t *name,
 342               dns_ttl_t ttl, dns_rdata_t *rdata)
 343 {
 344         dns_difftuple_t *tuple = NULL;
 345         isc_result_t result;
 346         result = dns_difftuple_create(diff->mctx, op,
 347                                       name, ttl, rdata, &tuple);
 348         if (result != ISC_R_SUCCESS)
 349                 return (result);
 350         return (do_one_tuple(&tuple, db, ver, diff));
 351 }
 352
 353 /**************************************************************************/
 354 /*
 355  * Callback-style iteration over rdatasets and rdatas.
 356  *
 357  * foreach_rrset() can be used to iterate over the RRsets
 358  * of a name and call a callback function with each
 359  * one.  Similarly, foreach_rr() can be used to iterate
 360  * over the individual RRs at name, optionally restricted
 361  * to RRs of a given type.
 362  *
 363  * The callback functions are called "actions" and take
 364  * two arguments: a void pointer for passing arbitrary
 365  * context information, and a pointer to the current RRset
 366  * or RR.  By convention, their names end in "_action".
 367  */
 368
 369 /*
 370  * XXXRTH  We might want to make this public somewhere in libdns.
 371  */
 372
 373 /*
 374  * Function type for foreach_rrset() iterator actions.
 375  */
 376 typedef isc_result_t rrset_func(void *data, dns_rdataset_t *rrset);
 377
 378 /*
 379  * Function type for foreach_rr() iterator actions.
 380  */
 381 typedef isc_result_t rr_func(void *data, rr_t *rr);
 382
 383 /*
 384  * Internal context struct for foreach_node_rr().
 385  */
 386 typedef struct {
 387         rr_func *       rr_action;
 388         void *          rr_action_data;
 389 } foreach_node_rr_ctx_t;
 390
 391 /*
 392  * Internal helper function for foreach_node_rr().
 393  */
 394 static isc_result_t
 395 foreach_node_rr_action(void *data, dns_rdataset_t *rdataset) {
 396         isc_result_t result;
 397         foreach_node_rr_ctx_t *ctx = data;
 398         for (result = dns_rdataset_first(rdataset);
 399              result == ISC_R_SUCCESS;
 400              result = dns_rdataset_next(rdataset))
 401         {
 402                 rr_t rr = { 0, DNS_RDATA_INIT };
 403
 404                 dns_rdataset_current(rdataset, &rr.rdata);
 405                 rr.ttl = rdataset->ttl;
 406                 result = (*ctx->rr_action)(ctx->rr_action_data, &rr);
 407                 if (result != ISC_R_SUCCESS)
 408                         return (result);
 409         }
 410         if (result != ISC_R_NOMORE)
 411                 return (result);
 412         return (ISC_R_SUCCESS);
 413 }
 414
 415 /*
 416  * For each rdataset of 'name' in 'ver' of 'db', call 'action'
 417  * with the rdataset and 'action_data' as arguments.  If the name
 418  * does not exist, do nothing.
 419  *
 420  * If 'action' returns an error, abort iteration and return the error.
 421  */
 422 static isc_result_t
 423 foreach_rrset(dns_db_t *db,
 424               dns_dbversion_t *ver,
 425               dns_name_t *name,
 426               rrset_func *action,
 427               void *action_data)
 428 {
 429         isc_result_t result;
 430         dns_dbnode_t *node;
 431         dns_rdatasetiter_t *iter;
 432
 433         node = NULL;
 434         result = dns_db_findnode(db, name, ISC_FALSE, &node);
 435         if (result == ISC_R_NOTFOUND)
 436                 return (ISC_R_SUCCESS);
 437         if (result != ISC_R_SUCCESS)
 438                 return (result);
 439
 440         iter = NULL;
 441         result = dns_db_allrdatasets(db, node, ver,
 442                                      (isc_stdtime_t) 0, &iter);
 443         if (result != ISC_R_SUCCESS)
 444                 goto cleanup_node;
 445
 446         for (result = dns_rdatasetiter_first(iter);
 447              result == ISC_R_SUCCESS;
 448              result = dns_rdatasetiter_next(iter))
 449         {
 450                 dns_rdataset_t rdataset;
 451
 452                 dns_rdataset_init(&rdataset);
 453                 dns_rdatasetiter_current(iter, &rdataset);
 454
 455                 result = (*action)(action_data, &rdataset);
 456
 457                 dns_rdataset_disassociate(&rdataset);
 458                 if (result != ISC_R_SUCCESS)
 459                         goto cleanup_iterator;
 460         }
 461         if (result == ISC_R_NOMORE)
 462                 result = ISC_R_SUCCESS;
 463
 464  cleanup_iterator:
 465         dns_rdatasetiter_destroy(&iter);
 466
 467  cleanup_node:
 468         dns_db_detachnode(db, &node);
 469
 470         return (result);
 471 }
 472
 473 /*
 474  * For each RR of 'name' in 'ver' of 'db', call 'action'
 475  * with the RR and 'action_data' as arguments.  If the name
 476  * does not exist, do nothing.
 477  *
 478  * If 'action' returns an error, abort iteration
 479  * and return the error.
 480  */
 481 static isc_result_t
 482 foreach_node_rr(dns_db_t *db,
 483             dns_dbversion_t *ver,
 484             dns_name_t *name,
 485             rr_func *rr_action,
 486             void *rr_action_data)
 487 {
 488         foreach_node_rr_ctx_t ctx;
 489         ctx.rr_action = rr_action;
 490         ctx.rr_action_data = rr_action_data;
 491         return (foreach_rrset(db, ver, name,
 492                               foreach_node_rr_action, &ctx));
 493 }
 494
 495
 496 /*
 497  * For each of the RRs specified by 'db', 'ver', 'name', 'type',
 498  * (which can be dns_rdatatype_any to match any type), and 'covers', call
 499  * 'action' with the RR and 'action_data' as arguments. If the name
 500  * does not exist, or if no RRset of the given type exists at the name,
 501  * do nothing.
 502  *
 503  * If 'action' returns an error, abort iteration and return the error.
 504  */
 505 static isc_result_t
 506 foreach_rr(dns_db_t *db,
 507            dns_dbversion_t *ver,
 508            dns_name_t *name,
 509            dns_rdatatype_t type,
 510            dns_rdatatype_t covers,
 511            rr_func *rr_action,
 512            void *rr_action_data)
 513 {
 514
 515         isc_result_t result;
 516         dns_dbnode_t *node;
 517         dns_rdataset_t rdataset;
 518
 519         if (type == dns_rdatatype_any)
 520                 return (foreach_node_rr(db, ver, name,
 521                                         rr_action, rr_action_data));
 522
 523         node = NULL;
 524         result = dns_db_findnode(db, name, ISC_FALSE, &node);
 525         if (result == ISC_R_NOTFOUND)
 526                 return (ISC_R_SUCCESS);
 527         if (result != ISC_R_SUCCESS)
 528                 return (result);
 529
 530         dns_rdataset_init(&rdataset);
 531         result = dns_db_findrdataset(db, node, ver, type, covers,
 532                                      (isc_stdtime_t) 0, &rdataset, NULL);
 533         if (result == ISC_R_NOTFOUND) {
 534                 result = ISC_R_SUCCESS;
 535                 goto cleanup_node;
 536         }
 537         if (result != ISC_R_SUCCESS)
 538                 goto cleanup_node;
 539
 540         for (result = dns_rdataset_first(&rdataset);
 541              result == ISC_R_SUCCESS;
 542              result = dns_rdataset_next(&rdataset))
 543         {
 544                 rr_t rr = { 0, DNS_RDATA_INIT };
 545                 dns_rdataset_current(&rdataset, &rr.rdata);
 546                 rr.ttl = rdataset.ttl;
 547                 result = (*rr_action)(rr_action_data, &rr);
 548                 if (result != ISC_R_SUCCESS)
 549                         goto cleanup_rdataset;
 550         }
 551         if (result != ISC_R_NOMORE)
 552                 goto cleanup_rdataset;
 553         result = ISC_R_SUCCESS;
 554
 555  cleanup_rdataset:
 556         dns_rdataset_disassociate(&rdataset);
 557  cleanup_node:
 558         dns_db_detachnode(db, &node);
 559
 560         return (result);
 561 }
 562
 563 /**************************************************************************/
 564 /*
 565  * Various tests on the database contents (for prerequisites, etc).
 566  */
 567
 568 /*
 569  * Function type for predicate functions that compare a database RR 'db_rr'
 570  * against an update RR 'update_rr'.
 571  */
 572 typedef isc_boolean_t rr_predicate(dns_rdata_t *update_rr, dns_rdata_t *db_rr);
 573
 574 /*
 575  * Helper function for rrset_exists().
 576  */
 577 static isc_result_t
 578 rrset_exists_action(void *data, rr_t *rr) {
 579         UNUSED(data);
 580         UNUSED(rr);
 581         return (ISC_R_EXISTS);
 582 }
 583
 584 /*
 585  * Utility macro for RR existence checking functions.
 586  *
 587  * If the variable 'result' has the value ISC_R_EXISTS or
 588  * ISC_R_SUCCESS, set *exists to ISC_TRUE or ISC_FALSE,
 589  * respectively, and return success.
 590  *
 591  * If 'result' has any other value, there was a failure.
 592  * Return the failure result code and do not set *exists.
 593  *
 594  * This would be more readable as "do { if ... } while(0)",
 595  * but that form generates tons of warnings on Solaris 2.6.
 596  */
 597 #define RETURN_EXISTENCE_FLAG                           \
 598         return ((result == ISC_R_EXISTS) ?              \
 599                 (*exists = ISC_TRUE, ISC_R_SUCCESS) :   \
 600                 ((result == ISC_R_SUCCESS) ?            \
 601                  (*exists = ISC_FALSE, ISC_R_SUCCESS) : \
 602                  result))
 603
 604 /*
 605  * Set '*exists' to true iff an rrset of the given type exists,
 606  * to false otherwise.
 607  */
 608 static isc_result_t
 609 rrset_exists(dns_db_t *db, dns_dbversion_t *ver,
 610              dns_name_t *name, dns_rdatatype_t type, dns_rdatatype_t covers,
 611              isc_boolean_t *exists)
 612 {
 613         isc_result_t result;
 614         result = foreach_rr(db, ver, name, type, covers,
 615                             rrset_exists_action, NULL);
 616         RETURN_EXISTENCE_FLAG;
 617 }
 618
 619 /*
 620  * Helper function for cname_incompatible_rrset_exists.
 621  */
 622 static isc_result_t
 623 cname_compatibility_action(void *data, dns_rdataset_t *rrset) {
 624         UNUSED(data);
 625         if (rrset->type != dns_rdatatype_cname &&
 626             ! dns_rdatatype_isdnssec(rrset->type))
 627                 return (ISC_R_EXISTS);
 628         return (ISC_R_SUCCESS);
 629 }
 630
 631 /*
 632  * Check whether there is an rrset incompatible with adding a CNAME RR,
 633  * i.e., anything but another CNAME (which can be replaced) or a
 634  * DNSSEC RR (which can coexist).
 635  *
 636  * If such an incompatible rrset exists, set '*exists' to ISC_TRUE.
 637  * Otherwise, set it to ISC_FALSE.
 638  */
 639 static isc_result_t
 640 cname_incompatible_rrset_exists(dns_db_t *db, dns_dbversion_t *ver,
 641                                 dns_name_t *name, isc_boolean_t *exists) {
 642         isc_result_t result;
 643         result = foreach_rrset(db, ver, name,
 644                                cname_compatibility_action, NULL);
 645         RETURN_EXISTENCE_FLAG;
 646 }
 647
 648 /*
 649  * Helper function for rr_count().
 650  */
 651 static isc_result_t
 652 count_rr_action(void *data, rr_t *rr) {
 653         int *countp = data;
 654         UNUSED(rr);
 655         (*countp)++;
 656         return (ISC_R_SUCCESS);
 657 }
 658
 659 /*
 660  * Count the number of RRs of 'type' belonging to 'name' in 'ver' of 'db'.
 661  */
 662 static isc_result_t
 663 rr_count(dns_db_t *db, dns_dbversion_t *ver, dns_name_t *name,
 664          dns_rdatatype_t type, dns_rdatatype_t covers, int *countp)
 665 {
 666         *countp = 0;
 667         return (foreach_rr(db, ver, name, type, covers,
 668                            count_rr_action, countp));
 669 }
 670
 671 /*
 672  * Context struct and helper function for name_exists().
 673  */
 674
 675 static isc_result_t
 676 name_exists_action(void *data, dns_rdataset_t *rrset) {
 677         UNUSED(data);
 678         UNUSED(rrset);
 679         return (ISC_R_EXISTS);
 680 }
 681
 682 /*
 683  * Set '*exists' to true iff the given name exists, to false otherwise.
 684  */
 685 static isc_result_t
 686 name_exists(dns_db_t *db, dns_dbversion_t *ver, dns_name_t *name,
 687             isc_boolean_t *exists)
 688 {
 689         isc_result_t result;
 690         result = foreach_rrset(db, ver, name,
 691                                name_exists_action, NULL);
 692         RETURN_EXISTENCE_FLAG;
 693 }
 694
 695 typedef struct {
 696         dns_name_t *name, *signer;
 697         dns_ssutable_t *table;
 698 } ssu_check_t;
 699
 700 static isc_result_t
 701 ssu_checkrule(void *data, dns_rdataset_t *rrset) {
 702         ssu_check_t *ssuinfo = data;
 703         isc_boolean_t result;
 704
 705         /*
 706          * If we're deleting all records, it's ok to delete RRSIG and NSEC even
 707          * if we're normally not allowed to.
 708          */
 709         if (rrset->type == dns_rdatatype_rrsig ||
 710             rrset->type == dns_rdatatype_nsec)
 711                 return (ISC_R_SUCCESS);
 712         result = dns_ssutable_checkrules(ssuinfo->table, ssuinfo->signer,
 713                                          ssuinfo->name, rrset->type);
 714         return (result == ISC_TRUE ? ISC_R_SUCCESS : ISC_R_FAILURE);
 715 }
 716
 717 static isc_boolean_t
 718 ssu_checkall(dns_db_t *db, dns_dbversion_t *ver, dns_name_t *name,
 719              dns_ssutable_t *ssutable, dns_name_t *signer)
 720 {
 721         isc_result_t result;
 722         ssu_check_t ssuinfo;
 723
 724         ssuinfo.name = name;
 725         ssuinfo.table = ssutable;
 726         ssuinfo.signer = signer;
 727         result = foreach_rrset(db, ver, name, ssu_checkrule, &ssuinfo);
 728         return (ISC_TF(result == ISC_R_SUCCESS));
 729 }
 730
 731 /**************************************************************************/
 732 /*
 733  * Checking of "RRset exists (value dependent)" prerequisites.
 734  *
 735  * In the RFC2136 section 3.2.5, this is the pseudocode involving
 736  * a variable called "temp", a mapping of <name, type> tuples to rrsets.
 737  *
 738  * Here, we represent the "temp" data structure as (non-minimial) "dns_diff_t"
 739  * where each typle has op==DNS_DIFFOP_EXISTS.
 740  */
 741
 742
 743 /*
 744  * Append a tuple asserting the existence of the RR with
 745  * 'name' and 'rdata' to 'diff'.
 746  */
 747 static isc_result_t
 748 temp_append(dns_diff_t *diff, dns_name_t *name, dns_rdata_t *rdata) {
 749         isc_result_t result;
 750         dns_difftuple_t *tuple = NULL;
 751
 752         REQUIRE(DNS_DIFF_VALID(diff));
 753         CHECK(dns_difftuple_create(diff->mctx, DNS_DIFFOP_EXISTS,
 754                                       name, 0, rdata, &tuple));
 755         ISC_LIST_APPEND(diff->tuples, tuple, link);
 756  failure:
 757         return (result);
 758 }
 759
 760 /*
 761  * Compare two rdatasets represented as sorted lists of tuples.
 762  * All list elements must have the same owner name and type.
 763  * Return ISC_R_SUCCESS if the rdatasets are equal, rcode(dns_rcode_nxrrset)
 764  * if not.
 765  */
 766 static isc_result_t
 767 temp_check_rrset(dns_difftuple_t *a, dns_difftuple_t *b) {
 768         for (;;) {
 769                 if (a == NULL || b == NULL)
 770                         break;
 771                 INSIST(a->op == DNS_DIFFOP_EXISTS &&
 772                        b->op == DNS_DIFFOP_EXISTS);
 773                 INSIST(a->rdata.type == b->rdata.type);
 774                 INSIST(dns_name_equal(&a->name, &b->name));
 775                 if (dns_rdata_compare(&a->rdata, &b->rdata) != 0)
 776                         return (DNS_R_NXRRSET);
 777                 a = ISC_LIST_NEXT(a, link);
 778                 b = ISC_LIST_NEXT(b, link);
 779         }
 780         if (a != NULL || b != NULL)
 781                 return (DNS_R_NXRRSET);
 782         return (ISC_R_SUCCESS);
 783 }
 784
 785 /*
 786  * A comparison function defining the sorting order for the entries
 787  * in the "temp" data structure.  The major sort key is the owner name,
 788  * followed by the type and rdata.
 789  */
 790 static int
 791 temp_order(const void *av, const void *bv) {
 792         dns_difftuple_t const * const *ap = av;
 793         dns_difftuple_t const * const *bp = bv;
 794         dns_difftuple_t const *a = *ap;
 795         dns_difftuple_t const *b = *bp;
 796         int r;
 797         r = dns_name_compare(&a->name, &b->name);
 798         if (r != 0)
 799                 return (r);
 800         r = (b->rdata.type - a->rdata.type);
 801         if (r != 0)
 802                 return (r);
 803         r = dns_rdata_compare(&a->rdata, &b->rdata);
 804         return (r);
 805 }
 806
 807 /*
 808  * Check the "RRset exists (value dependent)" prerequisite information
 809  * in 'temp' against the contents of the database 'db'.
 810  *
 811  * Return ISC_R_SUCCESS if the prerequisites are satisfied,
 812  * rcode(dns_rcode_nxrrset) if not.
 813  *
 814  * 'temp' must be pre-sorted.
 815  */
 816
 817 static isc_result_t
 818 temp_check(isc_mem_t *mctx, dns_diff_t *temp, dns_db_t *db,
 819            dns_dbversion_t *ver, dns_name_t *tmpname, dns_rdatatype_t *typep)
 820 {
 821         isc_result_t result;
 822         dns_name_t *name;
 823         dns_dbnode_t *node;
 824         dns_difftuple_t *t;
 825         dns_diff_t trash;
 826
 827         dns_diff_init(mctx, &trash);
 828
 829         /*
 830          * For each name and type in the prerequisites,
 831          * construct a sorted rdata list of the corresponding
 832          * database contents, and compare the lists.
 833          */
 834         t = ISC_LIST_HEAD(temp->tuples);
 835         while (t != NULL) {
 836                 name = &t->name;
 837                 (void)dns_name_copy(name, tmpname, NULL);
 838                 *typep = t->rdata.type;
 839
 840                 /* A new unique name begins here. */
 841                 node = NULL;
 842                 result = dns_db_findnode(db, name, ISC_FALSE, &node);
 843                 if (result == ISC_R_NOTFOUND)
 844                         return (DNS_R_NXRRSET);
 845                 if (result != ISC_R_SUCCESS)
 846                         return (result);
 847
 848                 /* A new unique type begins here. */
 849                 while (t != NULL && dns_name_equal(&t->name, name)) {
 850                         dns_rdatatype_t type, covers;
 851                         dns_rdataset_t rdataset;
 852                         dns_diff_t d_rrs; /* Database RRs with
 853                                                 this name and type */
 854                         dns_diff_t u_rrs; /* Update RRs with
 855                                                 this name and type */
 856
 857                         *typep = type = t->rdata.type;
 858                         if (type == dns_rdatatype_rrsig ||
 859                             type == dns_rdatatype_sig)
 860                                 covers = dns_rdata_covers(&t->rdata);
 861                         else
 862                                 covers = 0;
 863
 864                         /*
 865                          * Collect all database RRs for this name and type
 866                          * onto d_rrs and sort them.
 867                          */
 868                         dns_rdataset_init(&rdataset);
 869                         result = dns_db_findrdataset(db, node, ver, type,
 870                                                      covers, (isc_stdtime_t) 0,
 871                                                      &rdataset, NULL);
 872                         if (result != ISC_R_SUCCESS) {
 873                                 dns_db_detachnode(db, &node);
 874                                 return (DNS_R_NXRRSET);
 875                         }
 876
 877                         dns_diff_init(mctx, &d_rrs);
 878                         dns_diff_init(mctx, &u_rrs);
 879
 880                         for (result = dns_rdataset_first(&rdataset);
 881                              result == ISC_R_SUCCESS;
 882                              result = dns_rdataset_next(&rdataset))
 883                         {
 884                                 dns_rdata_t rdata = DNS_RDATA_INIT;
 885                                 dns_rdataset_current(&rdataset, &rdata);
 886                                 result = temp_append(&d_rrs, name, &rdata);
 887                                 if (result != ISC_R_SUCCESS)
 888                                         goto failure;
 889                         }
 890                         if (result != ISC_R_NOMORE)
 891                                 goto failure;
 892                         result = dns_diff_sort(&d_rrs, temp_order);
 893                         if (result != ISC_R_SUCCESS)
 894                                 goto failure;
 895
 896                         /*
 897                          * Collect all update RRs for this name and type
 898                          * onto u_rrs.  No need to sort them here -
 899                          * they are already sorted.
 900                          */
 901                         while (t != NULL &&
 902                                dns_name_equal(&t->name, name) &&
 903                                t->rdata.type == type)
 904                         {
 905                                 dns_difftuple_t *next =
 906                                         ISC_LIST_NEXT(t, link);
 907                                 ISC_LIST_UNLINK(temp->tuples, t, link);
 908                                 ISC_LIST_APPEND(u_rrs.tuples, t, link);
 909                                 t = next;
 910                         }
 911
 912                         /* Compare the two sorted lists. */
 913                         result = temp_check_rrset(ISC_LIST_HEAD(u_rrs.tuples),
 914                                                   ISC_LIST_HEAD(d_rrs.tuples));
 915                         if (result != ISC_R_SUCCESS)
 916                                 goto failure;
 917
 918                         /*
 919                          * We are done with the tuples, but we can't free
 920                          * them yet because "name" still points into one
 921                          * of them.  Move them on a temporary list.
 922                          */
 923                         ISC_LIST_APPENDLIST(trash.tuples, u_rrs.tuples, link);
 924                         ISC_LIST_APPENDLIST(trash.tuples, d_rrs.tuples, link);
 925                         dns_rdataset_disassociate(&rdataset);
 926
 927                         continue;
 928
 929                     failure:
 930                         dns_diff_clear(&d_rrs);
 931                         dns_diff_clear(&u_rrs);
 932                         dns_diff_clear(&trash);
 933                         dns_rdataset_disassociate(&rdataset);
 934                         dns_db_detachnode(db, &node);
 935                         return (result);
 936                 }
 937
 938                 dns_db_detachnode(db, &node);
 939         }
 940
 941         dns_diff_clear(&trash);
 942         return (ISC_R_SUCCESS);
 943 }
 944
 945 /**************************************************************************/
 946 /*
 947  * Conditional deletion of RRs.
 948  */
 949
 950 /*
 951  * Context structure for delete_if().
 952  */
 953
 954 typedef struct {
 955         rr_predicate *predicate;
 956         dns_db_t *db;
 957         dns_dbversion_t *ver;
 958         dns_diff_t *diff;
 959         dns_name_t *name;
 960         dns_rdata_t *update_rr;
 961 } conditional_delete_ctx_t;
 962
 963 /*
 964  * Predicate functions for delete_if().
 965  */
 966
 967 /*
 968  * Return true iff 'db_rr' is neither a SOA nor an NS RR nor
 969  * an RRSIG nor a NSEC.
 970  */
 971 static isc_boolean_t
 972 type_not_soa_nor_ns_p(dns_rdata_t *update_rr, dns_rdata_t *db_rr) {
 973         UNUSED(update_rr);
 974         return ((db_rr->type != dns_rdatatype_soa &&
 975                  db_rr->type != dns_rdatatype_ns &&
 976                  db_rr->type != dns_rdatatype_rrsig &&
 977                  db_rr->type != dns_rdatatype_nsec) ?
 978                 ISC_TRUE : ISC_FALSE);
 979 }
 980
 981 /*
 982  * Return true iff 'db_rr' is neither a RRSIG nor a NSEC.
 983  */
 984 static isc_boolean_t
 985 type_not_dnssec(dns_rdata_t *update_rr, dns_rdata_t *db_rr) {
 986         UNUSED(update_rr);
 987         return ((db_rr->type != dns_rdatatype_rrsig &&
 988                  db_rr->type != dns_rdatatype_nsec) ?
 989                 ISC_TRUE : ISC_FALSE);
 990 }
 991
 992 /*
 993  * Return true always.
 994  */
 995 static isc_boolean_t
 996 true_p(dns_rdata_t *update_rr, dns_rdata_t *db_rr) {
 997         UNUSED(update_rr);
 998         UNUSED(db_rr);
 999         return (ISC_TRUE);
1000 }
1001
1002 /*
1003  * Return true iff the two RRs have identical rdata.
1004  */
1005 static isc_boolean_t
1006 rr_equal_p(dns_rdata_t *update_rr, dns_rdata_t *db_rr) {
1007         /*
1008          * XXXRTH  This is not a problem, but we should consider creating
1009          *         dns_rdata_equal() (that used dns_name_equal()), since it
1010          *         would be faster.  Not a priority.
1011          */
1012         return (dns_rdata_compare(update_rr, db_rr) == 0 ?
1013                 ISC_TRUE : ISC_FALSE);
1014 }
1015
1016 /*
1017  * Return true iff 'update_rr' should replace 'db_rr' according
1018  * to the special RFC2136 rules for CNAME, SOA, and WKS records.
1019  *
1020  * RFC2136 does not mention NSEC or DNAME, but multiple NSECs or DNAMEs
1021  * make little sense, so we replace those, too.
1022  */
1023 static isc_boolean_t
1024 replaces_p(dns_rdata_t *update_rr, dns_rdata_t *db_rr) {
1025         if (db_rr->type != update_rr->type)
1026                 return (ISC_FALSE);
1027         if (db_rr->type == dns_rdatatype_cname)
1028                 return (ISC_TRUE);
1029         if (db_rr->type == dns_rdatatype_dname)
1030                 return (ISC_TRUE);
1031         if (db_rr->type == dns_rdatatype_soa)
1032                 return (ISC_TRUE);
1033         if (db_rr->type == dns_rdatatype_nsec)
1034                 return (ISC_TRUE);
1035         if (db_rr->type == dns_rdatatype_wks) {
1036                 /*
1037                  * Compare the address and protocol fields only.  These
1038                  * form the first five bytes of the RR data.  Do a
1039                  * raw binary comparison; unpacking the WKS RRs using
1040                  * dns_rdata_tostruct() might be cleaner in some ways,
1041                  * but it would require us to pass around an mctx.
1042                  */
1043                 INSIST(db_rr->length >= 5 && update_rr->length >= 5);
1044                 return (memcmp(db_rr->data, update_rr->data, 5) == 0 ?
1045                         ISC_TRUE : ISC_FALSE);
1046         }
1047         return (ISC_FALSE);
1048 }
1049
1050 /*
1051  * Internal helper function for delete_if().
1052  */
1053 static isc_result_t
1054 delete_if_action(void *data, rr_t *rr) {
1055         conditional_delete_ctx_t *ctx = data;
1056         if ((*ctx->predicate)(ctx->update_rr, &rr->rdata)) {
1057                 isc_result_t result;
1058                 result = update_one_rr(ctx->db, ctx->ver, ctx->diff,
1059                                        DNS_DIFFOP_DEL, ctx->name,
1060                                        rr->ttl, &rr->rdata);
1061                 return (result);
1062         } else {
1063                 return (ISC_R_SUCCESS);
1064         }
1065 }
1066
1067 /*
1068  * Conditionally delete RRs.  Apply 'predicate' to the RRs
1069  * specified by 'db', 'ver', 'name', and 'type' (which can
1070  * be dns_rdatatype_any to match any type).  Delete those
1071  * RRs for which the predicate returns true, and log the
1072  * deletions in 'diff'.
1073  */
1074 static isc_result_t
1075 delete_if(rr_predicate *predicate,
1076           dns_db_t *db,
1077           dns_dbversion_t *ver,
1078           dns_name_t *name,
1079           dns_rdatatype_t type,
1080           dns_rdatatype_t covers,
1081           dns_rdata_t *update_rr,
1082           dns_diff_t *diff)
1083 {
1084         conditional_delete_ctx_t ctx;
1085         ctx.predicate = predicate;
1086         ctx.db = db;
1087         ctx.ver = ver;
1088         ctx.diff = diff;
1089         ctx.name = name;
1090         ctx.update_rr = update_rr;
1091         return (foreach_rr(db, ver, name, type, covers,
1092                            delete_if_action, &ctx));
1093 }
1094
1095 /**************************************************************************/
1096 /*
1097  * Prepare an RR for the addition of the new RR 'ctx->update_rr',
1098  * with TTL 'ctx->update_rr_ttl', to its rdataset, by deleting
1099  * the RRs if it is replaced by the new RR or has a conflicting TTL.
1100  * The necessary changes are appended to ctx->del_diff and ctx->add_diff;
1101  * we need to do all deletions before any additions so that we don't run
1102  * into transient states with conflicting TTLs.
1103  */
1104
1105 typedef struct {
1106         dns_db_t *db;
1107         dns_dbversion_t *ver;
1108         dns_diff_t *diff;
1109         dns_name_t *name;
1110         dns_rdata_t *update_rr;
1111         dns_ttl_t update_rr_ttl;
1112         isc_boolean_t ignore_add;
1113         dns_diff_t del_diff;
1114         dns_diff_t add_diff;
1115 } add_rr_prepare_ctx_t;
1116
1117 static isc_result_t
1118 add_rr_prepare_action(void *data, rr_t *rr) {
1119         isc_result_t result = ISC_R_SUCCESS;
1120         add_rr_prepare_ctx_t *ctx = data;
1121         dns_difftuple_t *tuple = NULL;
1122         isc_boolean_t equal;
1123
1124         /*
1125          * If the update RR is a "duplicate" of the update RR,
1126          * the update should be silently ignored.
1127          */
1128         equal = ISC_TF(dns_rdata_compare(&rr->rdata, ctx->update_rr) == 0);
1129         if (equal && rr->ttl == ctx->update_rr_ttl) {
1130                 ctx->ignore_add = ISC_TRUE;
1131                 return (ISC_R_SUCCESS);
1132         }
1133
1134         /*
1135          * If this RR is "equal" to the update RR, it should
1136          * be deleted before the update RR is added.
1137          */
1138         if (replaces_p(ctx->update_rr, &rr->rdata)) {
1139                 CHECK(dns_difftuple_create(ctx->del_diff.mctx,
1140                                            DNS_DIFFOP_DEL, ctx->name,
1141                                            rr->ttl,
1142                                            &rr->rdata,
1143                                            &tuple));
1144                 dns_diff_append(&ctx->del_diff, &tuple);
1145                 return (ISC_R_SUCCESS);
1146         }
1147
1148         /*
1149          * If this RR differs in TTL from the update RR,
1150          * its TTL must be adjusted.
1151          */
1152         if (rr->ttl != ctx->update_rr_ttl) {
1153                 CHECK(dns_difftuple_create(ctx->del_diff.mctx,
1154                                            DNS_DIFFOP_DEL, ctx->name,
1155                                            rr->ttl,
1156                                            &rr->rdata,
1157                                            &tuple));
1158                 dns_diff_append(&ctx->del_diff, &tuple);
1159                 if (!equal) {
1160                         CHECK(dns_difftuple_create(ctx->add_diff.mctx,
1161                                                    DNS_DIFFOP_ADD, ctx->name,
1162                                                    ctx->update_rr_ttl,
1163                                                    &rr->rdata,
1164                                                    &tuple));
1165                         dns_diff_append(&ctx->add_diff, &tuple);
1166                 }
1167         }
1168  failure:
1169         return (result);
1170 }
1171
1172 /**************************************************************************/
1173 /*
1174  * Miscellaneous subroutines.
1175  */
1176
1177 /*
1178  * Extract a single update RR from 'section' of dynamic update message
1179  * 'msg', with consistency checking.
1180  *
1181  * Stores the owner name, rdata, and TTL of the update RR at 'name',
1182  * 'rdata', and 'ttl', respectively.
1183  */
1184 static void
1185 get_current_rr(dns_message_t *msg, dns_section_t section,
1186                dns_rdataclass_t zoneclass,
1187                dns_name_t **name, dns_rdata_t *rdata, dns_rdatatype_t *covers,
1188                dns_ttl_t *ttl,
1189                dns_rdataclass_t *update_class)
1190 {
1191         dns_rdataset_t *rdataset;
1192         isc_result_t result;
1193         dns_message_currentname(msg, section, name);
1194         rdataset = ISC_LIST_HEAD((*name)->list);
1195         INSIST(rdataset != NULL);
1196         INSIST(ISC_LIST_NEXT(rdataset, link) == NULL);
1197         *covers = rdataset->covers;
1198         *ttl = rdataset->ttl;
1199         result = dns_rdataset_first(rdataset);
1200         INSIST(result == ISC_R_SUCCESS);
1201         dns_rdataset_current(rdataset, rdata);
1202         INSIST(dns_rdataset_next(rdataset) == ISC_R_NOMORE);
1203         *update_class = rdata->rdclass;
1204         rdata->rdclass = zoneclass;
1205 }
1206
1207 /*
1208  * Increment the SOA serial number of database 'db', version 'ver'.
1209  * Replace the SOA record in the database, and log the
1210  * change in 'diff'.
1211  */
1212
1213         /*
1214          * XXXRTH  Failures in this routine will be worth logging, when
1215          *         we have a logging system.  Failure to find the zonename
1216          *         or the SOA rdataset warrant at least an UNEXPECTED_ERROR().
1217          */
1218
1219 static isc_result_t
1220 increment_soa_serial(dns_db_t *db, dns_dbversion_t *ver,
1221                      dns_diff_t *diff, isc_mem_t *mctx)
1222 {
1223         dns_difftuple_t *deltuple = NULL;
1224         dns_difftuple_t *addtuple = NULL;
1225         isc_uint32_t serial;
1226         isc_result_t result;
1227
1228         CHECK(dns_db_createsoatuple(db, ver, mctx, DNS_DIFFOP_DEL, &deltuple));
1229         CHECK(dns_difftuple_copy(deltuple, &addtuple));
1230         addtuple->op = DNS_DIFFOP_ADD;
1231
1232         serial = dns_soa_getserial(&addtuple->rdata);
1233
1234         /* RFC1982 */
1235         serial = (serial + 1) & 0xFFFFFFFF;
1236         if (serial == 0)
1237                 serial = 1;
1238
1239         dns_soa_setserial(serial, &addtuple->rdata);
1240         CHECK(do_one_tuple(&deltuple, db, ver, diff));
1241         CHECK(do_one_tuple(&addtuple, db, ver, diff));
1242         result = ISC_R_SUCCESS;
1243
1244  failure:
1245         if (addtuple != NULL)
1246                 dns_difftuple_free(&addtuple);
1247         if (deltuple != NULL)
1248                 dns_difftuple_free(&deltuple);
1249         return (result);
1250 }
1251
1252 /*
1253  * Check that the new SOA record at 'update_rdata' does not
1254  * illegally cause the SOA serial number to decrease or stay
1255  * unchanged relative to the existing SOA in 'db'.
1256  *
1257  * Sets '*ok' to ISC_TRUE if the update is legal, ISC_FALSE if not.
1258  *
1259  * William King points out that RFC2136 is inconsistent about
1260  * the case where the serial number stays unchanged:
1261  *
1262  *   section 3.4.2.2 requires a server to ignore a SOA update request
1263  *   if the serial number on the update SOA is less_than_or_equal to
1264  *   the zone SOA serial.
1265  *
1266  *   section 3.6 requires a server to ignore a SOA update request if
1267  *   the serial is less_than the zone SOA serial.
1268  *
1269  * Paul says 3.4.2.2 is correct.
1270  *
1271  */
1272 static isc_result_t
1273 check_soa_increment(dns_db_t *db, dns_dbversion_t *ver,
1274                     dns_rdata_t *update_rdata,
1275                     isc_boolean_t *ok)
1276 {
1277         isc_uint32_t db_serial;
1278         isc_uint32_t update_serial;
1279         isc_result_t result;
1280
1281         update_serial = dns_soa_getserial(update_rdata);
1282
1283         result = dns_db_getsoaserial(db, ver, &db_serial);
1284         if (result != ISC_R_SUCCESS)
1285                 return (result);
1286
1287         if (DNS_SERIAL_GE(db_serial, update_serial)) {
1288                 *ok = ISC_FALSE;
1289         } else {
1290                 *ok = ISC_TRUE;
1291         }
1292
1293         return (ISC_R_SUCCESS);
1294
1295 }
1296
1297 /**************************************************************************/
1298 /*
1299  * Incremental updating of NSECs and RRSIGs.
1300  */
1301
1302 #define MAXZONEKEYS 32  /* Maximum number of zone keys supported. */
1303
1304 /*
1305  * We abuse the dns_diff_t type to represent a set of domain names
1306  * affected by the update.
1307  */
1308 static isc_result_t
1309 namelist_append_name(dns_diff_t *list, dns_name_t *name) {
1310         isc_result_t result;
1311         dns_difftuple_t *tuple = NULL;
1312         static dns_rdata_t dummy_rdata = { NULL, 0, 0, 0, 0,
1313                                            { (void*)(-1), (void*)(-1) } };
1314         CHECK(dns_difftuple_create(list->mctx, DNS_DIFFOP_EXISTS, name, 0,
1315                                    &dummy_rdata, &tuple));
1316         dns_diff_append(list, &tuple);
1317  failure:
1318         return (result);
1319 }
1320
1321 static isc_result_t
1322 namelist_append_subdomain(dns_db_t *db, dns_name_t *name, dns_diff_t *affected)
1323 {
1324         isc_result_t result;
1325         dns_fixedname_t fixedname;
1326         dns_name_t *child;
1327         dns_dbiterator_t *dbit = NULL;
1328
1329         dns_fixedname_init(&fixedname);
1330         child = dns_fixedname_name(&fixedname);
1331
1332         CHECK(dns_db_createiterator(db, ISC_FALSE, &dbit));
1333
1334         for (result = dns_dbiterator_seek(dbit, name);
1335              result == ISC_R_SUCCESS;
1336              result = dns_dbiterator_next(dbit))
1337         {
1338                 dns_dbnode_t *node = NULL;
1339                 CHECK(dns_dbiterator_current(dbit, &node, child));
1340                 dns_db_detachnode(db, &node);
1341                 if (! dns_name_issubdomain(child, name))
1342                         break;
1343                 CHECK(namelist_append_name(affected, child));
1344         }
1345         if (result == ISC_R_NOMORE)
1346                 result = ISC_R_SUCCESS;
1347  failure:
1348         if (dbit != NULL)
1349                 dns_dbiterator_destroy(&dbit);
1350         return (result);
1351 }
1352
1353
1354
1355 /*
1356  * Helper function for non_nsec_rrset_exists().
1357  */
1358 static isc_result_t
1359 is_non_nsec_action(void *data, dns_rdataset_t *rrset) {
1360         UNUSED(data);
1361         if (!(rrset->type == dns_rdatatype_nsec ||
1362               (rrset->type == dns_rdatatype_rrsig &&
1363                rrset->covers == dns_rdatatype_nsec)))
1364                 return (ISC_R_EXISTS);
1365         return (ISC_R_SUCCESS);
1366 }
1367
1368 /*
1369  * Check whether there is an rrset other than a NSEC or RRSIG NSEC,
1370  * i.e., anything that justifies the continued existence of a name
1371  * after a secure update.
1372  *
1373  * If such an rrset exists, set '*exists' to ISC_TRUE.
1374  * Otherwise, set it to ISC_FALSE.
1375  */
1376 static isc_result_t
1377 non_nsec_rrset_exists(dns_db_t *db, dns_dbversion_t *ver,
1378                      dns_name_t *name, isc_boolean_t *exists)
1379 {
1380         isc_result_t result;
1381         result = foreach_rrset(db, ver, name,
1382                                is_non_nsec_action, NULL);
1383         RETURN_EXISTENCE_FLAG;
1384 }
1385
1386 /*
1387  * A comparison function for sorting dns_diff_t:s by name.
1388  */
1389 static int
1390 name_order(const void *av, const void *bv) {
1391         dns_difftuple_t const * const *ap = av;
1392         dns_difftuple_t const * const *bp = bv;
1393         dns_difftuple_t const *a = *ap;
1394         dns_difftuple_t const *b = *bp;
1395         return (dns_name_compare(&a->name, &b->name));
1396 }
1397
1398 static isc_result_t
1399 uniqify_name_list(dns_diff_t *list) {
1400         isc_result_t result;
1401         dns_difftuple_t *p, *q;
1402
1403         CHECK(dns_diff_sort(list, name_order));
1404
1405         p = ISC_LIST_HEAD(list->tuples);
1406         while (p != NULL) {
1407                 do {
1408                         q = ISC_LIST_NEXT(p, link);
1409                         if (q == NULL || ! dns_name_equal(&p->name, &q->name))
1410                                 break;
1411                         ISC_LIST_UNLINK(list->tuples, q, link);
1412                         dns_difftuple_free(&q);
1413                 } while (1);
1414                 p = ISC_LIST_NEXT(p, link);
1415         }
1416  failure:
1417         return (result);
1418 }
1419
1420
1421 static isc_result_t
1422 is_glue(dns_db_t *db, dns_dbversion_t *ver, dns_name_t *name,
1423         isc_boolean_t *flag)
1424 {
1425         isc_result_t result;
1426         dns_fixedname_t foundname;
1427         dns_fixedname_init(&foundname);
1428         result = dns_db_find(db, name, ver, dns_rdatatype_any,
1429                              DNS_DBFIND_GLUEOK | DNS_DBFIND_NOWILD,
1430                              (isc_stdtime_t) 0, NULL,
1431                              dns_fixedname_name(&foundname),
1432                              NULL, NULL);
1433         if (result == ISC_R_SUCCESS) {
1434                 *flag = ISC_FALSE;
1435                 return (ISC_R_SUCCESS);
1436         } else if (result == DNS_R_ZONECUT) {
1437                 /*
1438                  * We are at the zonecut.  The name will have an NSEC, but
1439                  * non-delegation will be omitted from the type bit map.
1440                  */
1441                 *flag = ISC_FALSE;
1442                 return (ISC_R_SUCCESS);
1443         } else if (result == DNS_R_GLUE || result == DNS_R_DNAME) {
1444                 *flag = ISC_TRUE;
1445                 return (ISC_R_SUCCESS);
1446         } else {
1447                 return (result);
1448         }
1449 }
1450
1451 /*
1452  * Find the next/previous name that has a NSEC record.
1453  * In other words, skip empty database nodes and names that
1454  * have had their NSECs removed because they are obscured by
1455  * a zone cut.
1456  */
1457 static isc_result_t
1458 next_active(ns_client_t *client, dns_zone_t *zone, dns_db_t *db,
1459             dns_dbversion_t *ver, dns_name_t *oldname, dns_name_t *newname,
1460             isc_boolean_t forward)
1461 {
1462         isc_result_t result;
1463         dns_dbiterator_t *dbit = NULL;
1464         isc_boolean_t has_nsec;
1465         unsigned int wraps = 0;
1466
1467         CHECK(dns_db_createiterator(db, ISC_FALSE, &dbit));
1468
1469         CHECK(dns_dbiterator_seek(dbit, oldname));
1470         do {
1471                 dns_dbnode_t *node = NULL;
1472
1473                 if (forward)
1474                         result = dns_dbiterator_next(dbit);
1475                 else
1476                         result = dns_dbiterator_prev(dbit);
1477                 if (result == ISC_R_NOMORE) {
1478                         /*
1479                          * Wrap around.
1480                          */
1481                         if (forward)
1482                                 CHECK(dns_dbiterator_first(dbit));
1483                         else
1484                                 CHECK(dns_dbiterator_last(dbit));
1485                         wraps++;
1486                         if (wraps == 2) {
1487                                 update_log(client, zone, ISC_LOG_ERROR,
1488                                            "secure zone with no NSECs");
1489                                 result = DNS_R_BADZONE;
1490                                 goto failure;
1491                         }
1492                 }
1493                 CHECK(dns_dbiterator_current(dbit, &node, newname));
1494                 dns_db_detachnode(db, &node);
1495
1496                 /*
1497                  * The iterator may hold the tree lock, and
1498                  * rrset_exists() calls dns_db_findnode() which
1499                  * may try to reacquire it.  To avoid deadlock
1500                  * we must pause the iterator first.
1501                  */
1502                 CHECK(dns_dbiterator_pause(dbit));
1503                 CHECK(rrset_exists(db, ver, newname,
1504                                    dns_rdatatype_nsec, 0, &has_nsec));
1505
1506         } while (! has_nsec);
1507  failure:
1508         if (dbit != NULL)
1509                 dns_dbiterator_destroy(&dbit);
1510
1511         return (result);
1512 }
1513
1514 /*
1515  * Add a NSEC record for "name", recording the change in "diff".
1516  * The existing NSEC is removed.
1517  */
1518 static isc_result_t
1519 add_nsec(ns_client_t *client, dns_zone_t *zone, dns_db_t *db,
1520         dns_dbversion_t *ver, dns_name_t *name, dns_diff_t *diff)
1521 {
1522         isc_result_t result;
1523         dns_dbnode_t *node = NULL;
1524         unsigned char buffer[DNS_NSEC_BUFFERSIZE];
1525         dns_rdata_t rdata = DNS_RDATA_INIT;
1526         dns_difftuple_t *tuple = NULL;
1527         dns_fixedname_t fixedname;
1528         dns_name_t *target;
1529
1530         dns_fixedname_init(&fixedname);
1531         target = dns_fixedname_name(&fixedname);
1532
1533         /*
1534          * Find the successor name, aka NSEC target.
1535          */
1536         CHECK(next_active(client, zone, db, ver, name, target, ISC_TRUE));
1537
1538         /*
1539          * Create the NSEC RDATA.
1540          */
1541         CHECK(dns_db_findnode(db, name, ISC_FALSE, &node));
1542         dns_rdata_init(&rdata);
1543         CHECK(dns_nsec_buildrdata(db, ver, node, target, buffer, &rdata));
1544         dns_db_detachnode(db, &node);
1545
1546         /*
1547          * Delete the old NSEC and record the change.
1548          */
1549         CHECK(delete_if(true_p, db, ver, name, dns_rdatatype_nsec, 0,
1550                         NULL, diff));
1551         /*
1552          * Add the new NSEC and record the change.
1553          */
1554         CHECK(dns_difftuple_create(diff->mctx, DNS_DIFFOP_ADD, name,
1555                                    3600,        /* XXXRTH */
1556                                    &rdata, &tuple));
1557         CHECK(do_one_tuple(&tuple, db, ver, diff));
1558         INSIST(tuple == NULL);
1559
1560  failure:
1561         if (node != NULL)
1562                 dns_db_detachnode(db, &node);
1563         return (result);
1564 }
1565
1566 /*
1567  * Add a placeholder NSEC record for "name", recording the change in "diff".
1568  */
1569 static isc_result_t
1570 add_placeholder_nsec(dns_db_t *db, dns_dbversion_t *ver, dns_name_t *name,
1571                     dns_diff_t *diff) {
1572         isc_result_t result;
1573         dns_difftuple_t *tuple = NULL;
1574         isc_region_t r;
1575         unsigned char data[1] = { 0 }; /* The root domain, no bits. */
1576         dns_rdata_t rdata = DNS_RDATA_INIT;
1577
1578         r.base = data;
1579         r.length = sizeof(data);
1580         dns_rdata_fromregion(&rdata, dns_db_class(db), dns_rdatatype_nsec, &r);
1581         CHECK(dns_difftuple_create(diff->mctx, DNS_DIFFOP_ADD, name, 0,
1582                                    &rdata, &tuple));
1583         CHECK(do_one_tuple(&tuple, db, ver, diff));
1584  failure:
1585         return (result);
1586 }
1587
1588 static isc_result_t
1589 find_zone_keys(dns_zone_t *zone, dns_db_t *db, dns_dbversion_t *ver,
1590                isc_mem_t *mctx, unsigned int maxkeys,
1591                dst_key_t **keys, unsigned int *nkeys)
1592 {
1593         isc_result_t result;
1594         dns_dbnode_t *node = NULL;
1595         const char *directory = dns_zone_getkeydirectory(zone);
1596         CHECK(dns_db_findnode(db, dns_db_origin(db), ISC_FALSE, &node));
1597         CHECK(dns_dnssec_findzonekeys2(db, ver, node, dns_db_origin(db),
1598                                        directory, mctx, maxkeys, keys, nkeys));
1599  failure:
1600         if (node != NULL)
1601                 dns_db_detachnode(db, &node);
1602         return (result);
1603 }
1604
1605 /*
1606  * Add RRSIG records for an RRset, recording the change in "diff".
1607  */
1608 static isc_result_t
1609 add_sigs(dns_db_t *db, dns_dbversion_t *ver, dns_name_t *name,
1610          dns_rdatatype_t type, dns_diff_t *diff, dst_key_t **keys,
1611          unsigned int nkeys, isc_mem_t *mctx, isc_stdtime_t inception,
1612          isc_stdtime_t expire)
1613 {
1614         isc_result_t result;
1615         dns_dbnode_t *node = NULL;
1616         dns_rdataset_t rdataset;
1617         dns_rdata_t sig_rdata = DNS_RDATA_INIT;
1618         isc_buffer_t buffer;
1619         unsigned char data[1024]; /* XXX */
1620         unsigned int i;
1621
1622         dns_rdataset_init(&rdataset);
1623         isc_buffer_init(&buffer, data, sizeof(data));
1624
1625         /* Get the rdataset to sign. */
1626         CHECK(dns_db_findnode(db, name, ISC_FALSE, &node));
1627         CHECK(dns_db_findrdataset(db, node, ver, type, 0,
1628                                   (isc_stdtime_t) 0,
1629                                   &rdataset, NULL));
1630         dns_db_detachnode(db, &node);
1631
1632         for (i = 0; i < nkeys; i++) {
1633                 /* Calculate the signature, creating a RRSIG RDATA. */
1634                 CHECK(dns_dnssec_sign(name, &rdataset, keys[i],
1635                                       &inception, &expire,
1636                                       mctx, &buffer, &sig_rdata));
1637
1638                 /* Update the database and journal with the RRSIG. */
1639                 /* XXX inefficient - will cause dataset merging */
1640                 CHECK(update_one_rr(db, ver, diff, DNS_DIFFOP_ADD, name,
1641                                     rdataset.ttl, &sig_rdata));
1642                 dns_rdata_reset(&sig_rdata);
1643         }
1644
1645  failure:
1646         if (dns_rdataset_isassociated(&rdataset))
1647                 dns_rdataset_disassociate(&rdataset);
1648         if (node != NULL)
1649                 dns_db_detachnode(db, &node);
1650         return (result);
1651 }
1652
1653 /*
1654  * Update RRSIG and NSEC records affected by an update.  The original
1655  * update, including the SOA serial update but exluding the RRSIG & NSEC
1656  * changes, is in "diff" and has already been applied to "newver" of "db".
1657  * The database version prior to the update is "oldver".
1658  *
1659  * The necessary RRSIG and NSEC changes will be applied to "newver"
1660  * and added (as a minimal diff) to "diff".
1661  *
1662  * The RRSIGs generated will be valid for 'sigvalidityinterval' seconds.
1663  */
1664 static isc_result_t
1665 update_signatures(ns_client_t *client, dns_zone_t *zone, dns_db_t *db,
1666                   dns_dbversion_t *oldver, dns_dbversion_t *newver,
1667                   dns_diff_t *diff, isc_uint32_t sigvalidityinterval)
1668 {
1669         isc_result_t result;
1670         dns_difftuple_t *t;
1671         dns_diff_t diffnames;
1672         dns_diff_t affected;
1673         dns_diff_t sig_diff;
1674         dns_diff_t nsec_diff;
1675         dns_diff_t nsec_mindiff;
1676         isc_boolean_t flag;
1677         dst_key_t *zone_keys[MAXZONEKEYS];
1678         unsigned int nkeys = 0;
1679         unsigned int i;
1680         isc_stdtime_t now, inception, expire;
1681
1682         dns_diff_init(client->mctx, &diffnames);
1683         dns_diff_init(client->mctx, &affected);
1684
1685         dns_diff_init(client->mctx, &sig_diff);
1686         dns_diff_init(client->mctx, &nsec_diff);
1687         dns_diff_init(client->mctx, &nsec_mindiff);
1688
1689         result = find_zone_keys(zone, db, newver, client->mctx,
1690                                 MAXZONEKEYS, zone_keys, &nkeys);
1691         if (result != ISC_R_SUCCESS) {
1692                 update_log(client, zone, ISC_LOG_ERROR,
1693                            "could not get zone keys for secure dynamic update");
1694                 goto failure;
1695         }
1696
1697         isc_stdtime_get(&now);
1698         inception = now - 3600; /* Allow for some clock skew. */
1699         expire = now + sigvalidityinterval;
1700
1701         /*
1702          * Find all RRsets directly affected by the update, and
1703          * update their RRSIGs.  Also build a list of names affected
1704          * by the update in "diffnames".
1705          */
1706         CHECK(dns_diff_sort(diff, temp_order));
1707
1708         t = ISC_LIST_HEAD(diff->tuples);
1709         while (t != NULL) {
1710                 dns_name_t *name = &t->name;
1711                 /* Now "name" is a new, unique name affected by the update. */
1712
1713                 CHECK(namelist_append_name(&diffnames, name));
1714
1715                 while (t != NULL && dns_name_equal(&t->name, name)) {
1716                         dns_rdatatype_t type;
1717                         type = t->rdata.type;
1718
1719                         /*
1720                          * Now "name" and "type" denote a new unique RRset
1721                          * affected by the update.
1722                          */
1723
1724                         /* Don't sign RRSIGs. */
1725                         if (type == dns_rdatatype_rrsig)
1726                                 goto skip;
1727
1728                         /*
1729                          * Delete all old RRSIGs covering this type, since they
1730                          * are all invalid when the signed RRset has changed.
1731                          * We may not be able to recreate all of them - tough.
1732                          */
1733                         CHECK(delete_if(true_p, db, newver, name,
1734                                         dns_rdatatype_rrsig, type,
1735                                         NULL, &sig_diff));
1736
1737                         /*
1738                          * If this RRset still exists after the update,
1739                          * add a new signature for it.
1740                          */
1741                         CHECK(rrset_exists(db, newver, name, type, 0, &flag));
1742                         if (flag) {
1743                                 CHECK(add_sigs(db, newver, name, type,
1744                                                &sig_diff, zone_keys, nkeys,
1745                                                client->mctx, inception,
1746                                                expire));
1747                         }
1748                 skip:
1749                         /* Skip any other updates to the same RRset. */
1750                         while (t != NULL &&
1751                                dns_name_equal(&t->name, name) &&
1752                                t->rdata.type == type)
1753                         {
1754                                 t = ISC_LIST_NEXT(t, link);
1755                         }
1756                 }
1757         }
1758
1759         /* Remove orphaned NSECs and RRSIG NSECs. */
1760         for (t = ISC_LIST_HEAD(diffnames.tuples);
1761              t != NULL;
1762              t = ISC_LIST_NEXT(t, link))
1763         {
1764                 CHECK(non_nsec_rrset_exists(db, newver, &t->name, &flag));
1765                 if (! flag) {
1766                         CHECK(delete_if(true_p, db, newver, &t->name,
1767                                         dns_rdatatype_any, 0,
1768                                         NULL, &sig_diff));
1769                 }
1770         }
1771
1772         /*
1773          * When a name is created or deleted, its predecessor needs to
1774          * have its NSEC updated.
1775          */
1776         for (t = ISC_LIST_HEAD(diffnames.tuples);
1777              t != NULL;
1778              t = ISC_LIST_NEXT(t, link))
1779         {
1780                 isc_boolean_t existed, exists;
1781                 dns_fixedname_t fixedname;
1782                 dns_name_t *prevname;
1783
1784                 dns_fixedname_init(&fixedname);
1785                 prevname = dns_fixedname_name(&fixedname);
1786
1787                 CHECK(name_exists(db, oldver, &t->name, &existed));
1788                 CHECK(name_exists(db, newver, &t->name, &exists));
1789                 if (exists == existed)
1790                         continue;
1791
1792                 /*
1793                  * Find the predecessor.
1794                  * When names become obscured or unobscured in this update
1795                  * transaction, we may find the wrong predecessor because
1796                  * the NSECs have not yet been updated to reflect the delegation
1797                  * change.  This should not matter because in this case,
1798                  * the correct predecessor is either the delegation node or
1799                  * a newly unobscured node, and those nodes are on the
1800                  * "affected" list in any case.
1801                  */
1802                 CHECK(next_active(client, zone, db, newver,
1803                                   &t->name, prevname, ISC_FALSE));
1804                 CHECK(namelist_append_name(&affected, prevname));
1805         }
1806
1807         /*
1808          * Find names potentially affected by delegation changes
1809          * (obscured by adding an NS or DNAME, or unobscured by
1810          * removing one).
1811          */
1812         for (t = ISC_LIST_HEAD(diffnames.tuples);
1813              t != NULL;
1814              t = ISC_LIST_NEXT(t, link))
1815         {
1816                 isc_boolean_t ns_existed, dname_existed;
1817                 isc_boolean_t ns_exists, dname_exists;
1818
1819                 CHECK(rrset_exists(db, oldver, &t->name, dns_rdatatype_ns, 0,
1820                                    &ns_existed));
1821                 CHECK(rrset_exists(db, oldver, &t->name, dns_rdatatype_dname, 0,
1822                                    &dname_existed));
1823                 CHECK(rrset_exists(db, newver, &t->name, dns_rdatatype_ns, 0,
1824                                    &ns_exists));
1825                 CHECK(rrset_exists(db, newver, &t->name, dns_rdatatype_dname, 0,
1826                                    &dname_exists));
1827                 if ((ns_exists || dname_exists) == (ns_existed || dname_existed))
1828                         continue;
1829                 /*
1830                  * There was a delegation change.  Mark all subdomains
1831                  * of t->name as potentially needing a NSEC update.
1832                  */
1833                 CHECK(namelist_append_subdomain(db, &t->name, &affected));
1834         }
1835
1836         ISC_LIST_APPENDLIST(affected.tuples, diffnames.tuples, link);
1837         INSIST(ISC_LIST_EMPTY(diffnames.tuples));
1838
1839         CHECK(uniqify_name_list(&affected));
1840
1841         /*
1842          * Determine which names should have NSECs, and delete/create
1843          * NSECs to make it so.  We don't know the final NSEC targets yet,
1844          * so we just create placeholder NSECs with arbitrary contents
1845          * to indicate that their respective owner names should be part of
1846          * the NSEC chain.
1847          */
1848         for (t = ISC_LIST_HEAD(affected.tuples);
1849              t != NULL;
1850              t = ISC_LIST_NEXT(t, link))
1851         {
1852                 isc_boolean_t exists;
1853                 CHECK(name_exists(db, newver, &t->name, &exists));
1854                 if (! exists)
1855                         continue;
1856                 CHECK(is_glue(db, newver, &t->name, &flag));
1857                 if (flag) {
1858                         /*
1859                          * This name is obscured.  Delete any
1860                          * existing NSEC record.
1861                          */
1862                         CHECK(delete_if(true_p, db, newver, &t->name,
1863                                         dns_rdatatype_nsec, 0,
1864                                         NULL, &nsec_diff));
1865                 } else {
1866                         /*
1867                          * This name is not obscured.  It should have a NSEC.
1868                          */
1869                         CHECK(rrset_exists(db, newver, &t->name,
1870                                            dns_rdatatype_nsec, 0, &flag));
1871                         if (! flag)
1872                                 CHECK(add_placeholder_nsec(db, newver, &t->name,
1873                                                           diff));
1874                 }
1875         }
1876
1877         /*
1878          * Now we know which names are part of the NSEC chain.
1879          * Make them all point at their correct targets.
1880          */
1881         for (t = ISC_LIST_HEAD(affected.tuples);
1882              t != NULL;
1883              t = ISC_LIST_NEXT(t, link))
1884         {
1885                 CHECK(rrset_exists(db, newver, &t->name,
1886                                    dns_rdatatype_nsec, 0, &flag));
1887                 if (flag) {
1888                         /*
1889                          * There is a NSEC, but we don't know if it is correct.
1890                          * Delete it and create a correct one to be sure.
1891                          * If the update was unnecessary, the diff minimization
1892                          * will take care of eliminating it from the journal,
1893                          * IXFRs, etc.
1894                          *
1895                          * The RRSIG bit should always be set in the NSECs
1896                          * we generate, because they will all get RRSIG NSECs.
1897                          * (XXX what if the zone keys are missing?).
1898                          * Because the RRSIG NSECs have not necessarily been
1899                          * created yet, the correctness of the bit mask relies
1900                          * on the assumption that NSECs are only created if
1901                          * there is other data, and if there is other data,
1902                          * there are other RRSIGs.
1903                          */
1904                         CHECK(add_nsec(client, zone, db, newver,
1905                                       &t->name, &nsec_diff));
1906                 }
1907         }
1908
1909         /*
1910          * Minimize the set of NSEC updates so that we don't
1911          * have to regenerate the RRSIG NSECs for NSECs that were
1912          * replaced with identical ones.
1913          */
1914         while ((t = ISC_LIST_HEAD(nsec_diff.tuples)) != NULL) {
1915                 ISC_LIST_UNLINK(nsec_diff.tuples, t, link);
1916                 dns_diff_appendminimal(&nsec_mindiff, &t);
1917         }
1918
1919         /* Update RRSIG NSECs. */
1920         for (t = ISC_LIST_HEAD(nsec_mindiff.tuples);
1921              t != NULL;
1922              t = ISC_LIST_NEXT(t, link))
1923         {
1924                 if (t->op == DNS_DIFFOP_DEL) {
1925                         CHECK(delete_if(true_p, db, newver, &t->name,
1926                                         dns_rdatatype_rrsig, dns_rdatatype_nsec,
1927                                         NULL, &sig_diff));
1928                 } else if (t->op == DNS_DIFFOP_ADD) {
1929                         CHECK(add_sigs(db, newver, &t->name, dns_rdatatype_nsec,
1930                                        &sig_diff, zone_keys, nkeys,
1931                                        client->mctx, inception, expire));
1932                 } else {
1933                         INSIST(0);
1934                 }
1935         }
1936
1937         /* Record our changes for the journal. */
1938         while ((t = ISC_LIST_HEAD(sig_diff.tuples)) != NULL) {
1939                 ISC_LIST_UNLINK(sig_diff.tuples, t, link);
1940                 dns_diff_appendminimal(diff, &t);
1941         }
1942         while ((t = ISC_LIST_HEAD(nsec_mindiff.tuples)) != NULL) {
1943                 ISC_LIST_UNLINK(nsec_mindiff.tuples, t, link);
1944                 dns_diff_appendminimal(diff, &t);
1945         }
1946
1947         INSIST(ISC_LIST_EMPTY(sig_diff.tuples));
1948         INSIST(ISC_LIST_EMPTY(nsec_diff.tuples));
1949         INSIST(ISC_LIST_EMPTY(nsec_mindiff.tuples));
1950
1951  failure:
1952         dns_diff_clear(&sig_diff);
1953         dns_diff_clear(&nsec_diff);
1954         dns_diff_clear(&nsec_mindiff);
1955
1956         dns_diff_clear(&affected);
1957         dns_diff_clear(&diffnames);
1958
1959         for (i = 0; i < nkeys; i++)
1960                 dst_key_free(&zone_keys[i]);
1961
1962         return (result);
1963 }
1964
1965
1966 /**************************************************************************/
1967 /*
1968  * The actual update code in all its glory.  We try to follow
1969  * the RFC2136 pseudocode as closely as possible.
1970  */
1971
1972 static isc_result_t
1973 send_update_event(ns_client_t *client, dns_zone_t *zone) {
1974         isc_result_t result = ISC_R_SUCCESS;
1975         update_event_t *event = NULL;
1976         isc_task_t *zonetask = NULL;
1977         ns_client_t *evclient;
1978
1979         event = (update_event_t *)
1980                 isc_event_allocate(client->mctx, client, DNS_EVENT_UPDATE,
1981                                    update_action, NULL, sizeof(*event));
1982         if (event == NULL)
1983                 FAIL(ISC_R_NOMEMORY);
1984         event->zone = zone;
1985         event->result = ISC_R_SUCCESS;
1986
1987         evclient = NULL;
1988         ns_client_attach(client, &evclient);
1989         INSIST(client->nupdates == 0);
1990         client->nupdates++;
1991         event->ev_arg = evclient;
1992
1993         dns_zone_gettask(zone, &zonetask);
1994         isc_task_send(zonetask, ISC_EVENT_PTR(&event));
1995
1996  failure:
1997         if (event != NULL)
1998                 isc_event_free(ISC_EVENT_PTR(&event));
1999         return (result);
2000 }
2001
2002 static void
2003 respond(ns_client_t *client, isc_result_t result) {
2004         isc_result_t msg_result;
2005
2006         msg_result = dns_message_reply(client->message, ISC_TRUE);
2007         if (msg_result != ISC_R_SUCCESS)
2008                 goto msg_failure;
2009         client->message->rcode = dns_result_torcode(result);
2010
2011         ns_client_send(client);
2012         return;
2013
2014  msg_failure:
2015         isc_log_write(ns_g_lctx, NS_LOGCATEGORY_UPDATE, NS_LOGMODULE_UPDATE,
2016                       ISC_LOG_ERROR,
2017                       "could not create update response message: %s",
2018                       isc_result_totext(msg_result));
2019         ns_client_next(client, msg_result);
2020 }
2021
2022 void
2023 ns_update_start(ns_client_t *client, isc_result_t sigresult) {
2024         dns_message_t *request = client->message;
2025         isc_result_t result;
2026         dns_name_t *zonename;
2027         dns_rdataset_t *zone_rdataset;
2028         dns_zone_t *zone = NULL;
2029
2030         /*
2031          * Interpret the zone section.
2032          */
2033         result = dns_message_firstname(request, DNS_SECTION_ZONE);
2034         if (result != ISC_R_SUCCESS)
2035                 FAILC(DNS_R_FORMERR,
2036                       "update zone section empty");
2037
2038         /*
2039          * The zone section must contain exactly one "question", and
2040          * it must be of type SOA.
2041          */
2042         zonename = NULL;
2043         dns_message_currentname(request, DNS_SECTION_ZONE, &zonename);
2044         zone_rdataset = ISC_LIST_HEAD(zonename->list);
2045         if (zone_rdataset->type != dns_rdatatype_soa)
2046                 FAILC(DNS_R_FORMERR,
2047                       "update zone section contains non-SOA");
2048         if (ISC_LIST_NEXT(zone_rdataset, link) != NULL)
2049                 FAILC(DNS_R_FORMERR,
2050                       "update zone section contains multiple RRs");
2051
2052         /* The zone section must have exactly one name. */
2053         result = dns_message_nextname(request, DNS_SECTION_ZONE);
2054         if (result != ISC_R_NOMORE)
2055                 FAILC(DNS_R_FORMERR,
2056                       "update zone section contains multiple RRs");
2057
2058         result = dns_zt_find(client->view->zonetable, zonename, 0, NULL,
2059                              &zone);
2060         if (result != ISC_R_SUCCESS)
2061                 FAILC(DNS_R_NOTAUTH,
2062                       "not authoritative for update zone");
2063
2064         switch(dns_zone_gettype(zone)) {
2065         case dns_zone_master:
2066                 /*
2067                  * We can now fail due to a bad signature as we now know
2068                  * that we are the master.
2069                  */
2070                 if (sigresult != ISC_R_SUCCESS)
2071                         FAIL(sigresult);
2072                 CHECK(send_update_event(client, zone));
2073                 break;
2074         case dns_zone_slave:
2075                 CHECK(checkupdateacl(client, dns_zone_getforwardacl(zone),
2076                                      "update forwarding", zonename, ISC_TRUE));
2077                 CHECK(send_forward_event(client, zone));
2078                 break;
2079         default:
2080                 FAILC(DNS_R_NOTAUTH,
2081                       "not authoritative for update zone");
2082         }
2083         return;
2084
2085  failure:
2086         /*
2087          * We failed without having sent an update event to the zone.
2088          * We are still in the client task context, so we can
2089          * simply give an error response without switching tasks.
2090          */
2091         respond(client, result);
2092         if (zone != NULL)
2093                 dns_zone_detach(&zone);
2094 }
2095
2096 /*
2097  * DS records are not allowed to exist without corresponding NS records,
2098  * draft-ietf-dnsext-delegation-signer-11.txt, 2.2 Protocol Change,
2099  * "DS RRsets MUST NOT appear at non-delegation points or at a zone's apex".
2100  */
2101
2102 static isc_result_t
2103 remove_orphaned_ds(dns_db_t *db, dns_dbversion_t *newver, dns_diff_t *diff) {
2104         isc_result_t result;
2105         isc_boolean_t ns_exists, ds_exists;
2106         dns_difftuple_t *t;
2107
2108         for (t = ISC_LIST_HEAD(diff->tuples);
2109              t != NULL;
2110              t = ISC_LIST_NEXT(t, link)) {
2111                 if (t->op != DNS_DIFFOP_DEL ||
2112                     t->rdata.type != dns_rdatatype_ns)
2113                         continue;
2114                 CHECK(rrset_exists(db, newver, &t->name, dns_rdatatype_ns, 0,
2115                                    &ns_exists));
2116                 if (ns_exists)
2117                         continue;
2118                 CHECK(rrset_exists(db, newver, &t->name, dns_rdatatype_ds, 0,
2119                                    &ds_exists));
2120                 if (!ds_exists)
2121                         continue;
2122                 CHECK(delete_if(true_p, db, newver, &t->name,
2123                                 dns_rdatatype_ds, 0, NULL, diff));
2124         }
2125         return (ISC_R_SUCCESS);
2126
2127  failure:
2128         return (result);
2129 }
2130
2131 static void
2132 update_action(isc_task_t *task, isc_event_t *event) {
2133         update_event_t *uev = (update_event_t *) event;
2134         dns_zone_t *zone = uev->zone;
2135         ns_client_t *client = (ns_client_t *)event->ev_arg;
2136
2137         isc_result_t result;
2138         dns_db_t *db = NULL;
2139         dns_dbversion_t *oldver = NULL;
2140         dns_dbversion_t *ver = NULL;
2141         dns_diff_t diff;        /* Pending updates. */
2142         dns_diff_t temp;        /* Pending RR existence assertions. */
2143         isc_boolean_t soa_serial_changed = ISC_FALSE;
2144         isc_mem_t *mctx = client->mctx;
2145         dns_rdatatype_t covers;
2146         dns_message_t *request = client->message;
2147         dns_rdataclass_t zoneclass;
2148         dns_name_t *zonename;
2149         dns_ssutable_t *ssutable = NULL;
2150         dns_fixedname_t tmpnamefixed;
2151         dns_name_t *tmpname = NULL;
2152
2153         INSIST(event->ev_type == DNS_EVENT_UPDATE);
2154
2155         dns_diff_init(mctx, &diff);
2156         dns_diff_init(mctx, &temp);
2157
2158         CHECK(dns_zone_getdb(zone, &db));
2159         zonename = dns_db_origin(db);
2160         zoneclass = dns_db_class(db);
2161         dns_zone_getssutable(zone, &ssutable);
2162         dns_db_currentversion(db, &oldver);
2163         CHECK(dns_db_newversion(db, &ver));
2164
2165         /*
2166          * Check prerequisites.
2167          */
2168
2169         for (result = dns_message_firstname(request, DNS_SECTION_PREREQUISITE);
2170              result == ISC_R_SUCCESS;
2171              result = dns_message_nextname(request, DNS_SECTION_PREREQUISITE))
2172         {
2173                 dns_name_t *name = NULL;
2174                 dns_rdata_t rdata = DNS_RDATA_INIT;
2175                 dns_ttl_t ttl;
2176                 dns_rdataclass_t update_class;
2177                 isc_boolean_t flag;
2178
2179                 get_current_rr(request, DNS_SECTION_PREREQUISITE, zoneclass,
2180                                &name, &rdata, &covers, &ttl, &update_class);
2181
2182                 if (ttl != 0)
2183                         FAILC(DNS_R_FORMERR, "prerequisite TTL is not zero");
2184
2185                 if (! dns_name_issubdomain(name, zonename))
2186                         FAILN(DNS_R_NOTZONE, name,
2187                                 "prerequisite name is out of zone");
2188
2189                 if (update_class == dns_rdataclass_any) {
2190                         if (rdata.length != 0)
2191                                 FAILC(DNS_R_FORMERR,
2192                                       "class ANY prerequisite "
2193                                       "RDATA is not empty");
2194                         if (rdata.type == dns_rdatatype_any) {
2195                                 CHECK(name_exists(db, ver, name, &flag));
2196                                 if (! flag) {
2197                                         FAILN(DNS_R_NXDOMAIN, name,
2198                                               "'name in use' prerequisite "
2199                                               "not satisfied");
2200                                 }
2201                         } else {
2202                                 CHECK(rrset_exists(db, ver, name,
2203                                                    rdata.type, covers, &flag));
2204                                 if (! flag) {
2205                                         /* RRset does not exist. */
2206                                         FAILNT(DNS_R_NXRRSET, name, rdata.type,
2207                                         "'rrset exists (value independent)' "
2208                                         "prerequisite not satisfied");
2209                                 }
2210                         }
2211                 } else if (update_class == dns_rdataclass_none) {
2212                         if (rdata.length != 0)
2213                                 FAILC(DNS_R_FORMERR,
2214                                       "class NONE prerequisite "
2215                                       "RDATA is not empty");
2216                         if (rdata.type == dns_rdatatype_any) {
2217                                 CHECK(name_exists(db, ver, name, &flag));
2218                                 if (flag) {
2219                                         FAILN(DNS_R_YXDOMAIN, name,
2220                                               "'name not in use' prerequisite "
2221                                               "not satisfied");
2222                                 }
2223                         } else {
2224                                 CHECK(rrset_exists(db, ver, name,
2225                                                    rdata.type, covers, &flag));
2226                                 if (flag) {
2227                                         /* RRset exists. */
2228                                         FAILNT(DNS_R_YXRRSET, name, rdata.type,
2229                                                "'rrset does not exist' "
2230                                                "prerequisite not satisfied");
2231                                 }
2232                         }
2233                 } else if (update_class == zoneclass) {
2234                         /* "temp<rr.name, rr.type> += rr;" */
2235                         result = temp_append(&temp, name, &rdata);
2236                         if (result != ISC_R_SUCCESS) {
2237                                 UNEXPECTED_ERROR(__FILE__, __LINE__,
2238                                          "temp entry creation failed: %s",
2239                                                  dns_result_totext(result));
2240                                 FAIL(ISC_R_UNEXPECTED);
2241                         }
2242                 } else {
2243                         FAILC(DNS_R_FORMERR, "malformed prerequisite");
2244                 }
2245         }
2246         if (result != ISC_R_NOMORE)
2247                 FAIL(result);
2248
2249
2250         /*
2251          * Perform the final check of the "rrset exists (value dependent)"
2252          * prerequisites.
2253          */
2254         if (ISC_LIST_HEAD(temp.tuples) != NULL) {
2255                 dns_rdatatype_t type;
2256
2257                 /*
2258                  * Sort the prerequisite records by owner name,
2259                  * type, and rdata.
2260                  */
2261                 result = dns_diff_sort(&temp, temp_order);
2262                 if (result != ISC_R_SUCCESS)
2263                         FAILC(result, "'RRset exists (value dependent)' "
2264                               "prerequisite not satisfied");
2265
2266                 dns_fixedname_init(&tmpnamefixed);
2267                 tmpname = dns_fixedname_name(&tmpnamefixed);
2268                 result = temp_check(mctx, &temp, db, ver, tmpname, &type);
2269                 if (result != ISC_R_SUCCESS)
2270                         FAILNT(result, tmpname, type,
2271                                "'RRset exists (value dependent)' "
2272                                "prerequisite not satisfied");
2273         }
2274
2275         update_log(client, zone, LOGLEVEL_DEBUG,
2276                    "prerequisites are OK");
2277
2278         /*
2279          * Check Requestor's Permissions.  It seems a bit silly to do this
2280          * only after prerequisite testing, but that is what RFC2136 says.
2281          */
2282         result = ISC_R_SUCCESS;
2283         if (ssutable == NULL)
2284                 CHECK(checkupdateacl(client, dns_zone_getupdateacl(zone),
2285                                      "update", zonename, ISC_FALSE));
2286         else if (client->signer == NULL)
2287                 CHECK(checkupdateacl(client, NULL, "update", zonename,
2288                                      ISC_FALSE));
2289
2290         if (dns_zone_getupdatedisabled(zone))
2291                 FAILC(DNS_R_REFUSED, "dynamic update temporarily disabled");
2292
2293         /*
2294          * Perform the Update Section Prescan.
2295          */
2296
2297         for (result = dns_message_firstname(request, DNS_SECTION_UPDATE);
2298              result == ISC_R_SUCCESS;
2299              result = dns_message_nextname(request, DNS_SECTION_UPDATE))
2300         {
2301                 dns_name_t *name = NULL;
2302                 dns_rdata_t rdata = DNS_RDATA_INIT;
2303                 dns_ttl_t ttl;
2304                 dns_rdataclass_t update_class;
2305                 get_current_rr(request, DNS_SECTION_UPDATE, zoneclass,
2306                                &name, &rdata, &covers, &ttl, &update_class);
2307
2308                 if (! dns_name_issubdomain(name, zonename))
2309                         FAILC(DNS_R_NOTZONE,
2310                               "update RR is outside zone");
2311                 if (update_class == zoneclass) {
2312                         /*
2313                          * Check for meta-RRs.  The RFC2136 pseudocode says
2314                          * check for ANY|AXFR|MAILA|MAILB, but the text adds
2315                          * "or any other QUERY metatype"
2316                          */
2317                         if (dns_rdatatype_ismeta(rdata.type)) {
2318                                 FAILC(DNS_R_FORMERR,
2319                                       "meta-RR in update");
2320                         }
2321                         result = dns_zone_checknames(zone, name, &rdata);
2322                         if (result != ISC_R_SUCCESS)
2323                                 FAIL(DNS_R_REFUSED);
2324                 } else if (update_class == dns_rdataclass_any) {
2325                         if (ttl != 0 || rdata.length != 0 ||
2326                             (dns_rdatatype_ismeta(rdata.type) &&
2327                              rdata.type != dns_rdatatype_any))
2328                                 FAILC(DNS_R_FORMERR,
2329                                       "meta-RR in update");
2330                 } else if (update_class == dns_rdataclass_none) {
2331                         if (ttl != 0 ||
2332                             dns_rdatatype_ismeta(rdata.type))
2333                                 FAILC(DNS_R_FORMERR,
2334                                       "meta-RR in update");
2335                 } else {
2336                         update_log(client, zone, ISC_LOG_WARNING,
2337                                    "update RR has incorrect class %d",
2338                                    update_class);
2339                         FAIL(DNS_R_FORMERR);
2340                 }
2341                 /*
2342                  * draft-ietf-dnsind-simple-secure-update-01 says
2343                  * "Unlike traditional dynamic update, the client
2344                  * is forbidden from updating NSEC records."
2345                  */
2346                 if (dns_db_issecure(db)) {
2347                         if (rdata.type == dns_rdatatype_nsec) {
2348                                 FAILC(DNS_R_REFUSED,
2349                                       "explicit NSEC updates are not allowed "
2350                                       "in secure zones");
2351                         }
2352                         else if (rdata.type == dns_rdatatype_rrsig) {
2353                                 FAILC(DNS_R_REFUSED,
2354                                       "explicit RRSIG updates are currently not "
2355                                       "supported in secure zones");
2356                         }
2357                 }
2358
2359                 if (ssutable != NULL && client->signer != NULL) {
2360                         if (rdata.type != dns_rdatatype_any) {
2361                                 if (!dns_ssutable_checkrules(ssutable,
2362                                                              client->signer,
2363                                                              name, rdata.type))
2364                                         FAILC(DNS_R_REFUSED,
2365                                               "rejected by secure update");
2366                         }
2367                         else {
2368                                 if (!ssu_checkall(db, ver, name, ssutable,
2369                                                   client->signer))
2370                                         FAILC(DNS_R_REFUSED,
2371                                               "rejected by secure update");
2372                         }
2373                 }
2374         }
2375         if (result != ISC_R_NOMORE)
2376                 FAIL(result);
2377
2378         update_log(client, zone, LOGLEVEL_DEBUG,
2379                    "update section prescan OK");
2380
2381         /*
2382          * Process the Update Section.
2383          */
2384
2385         for (result = dns_message_firstname(request, DNS_SECTION_UPDATE);
2386              result == ISC_R_SUCCESS;
2387              result = dns_message_nextname(request, DNS_SECTION_UPDATE))
2388         {
2389                 dns_name_t *name = NULL;
2390                 dns_rdata_t rdata = DNS_RDATA_INIT;
2391                 dns_ttl_t ttl;
2392                 dns_rdataclass_t update_class;
2393                 isc_boolean_t flag;
2394
2395                 get_current_rr(request, DNS_SECTION_UPDATE, zoneclass,
2396                                &name, &rdata, &covers, &ttl, &update_class);
2397
2398                 if (update_class == zoneclass) {
2399
2400                         /*
2401                          * RFC 1123 doesn't allow MF and MD in master zones.                             */
2402                         if (rdata.type == dns_rdatatype_md ||
2403                             rdata.type == dns_rdatatype_mf) {
2404                                 char typebuf[DNS_RDATATYPE_FORMATSIZE];
2405
2406                                 dns_rdatatype_format(rdata.type, typebuf,
2407                                                      sizeof(typebuf));
2408                                 update_log(client, zone, LOGLEVEL_PROTOCOL,
2409                                            "attempt to add %s ignored",
2410                                            typebuf);
2411                                 continue;
2412                         }
2413                         if (rdata.type == dns_rdatatype_ns &&
2414                             dns_name_iswildcard(name)) {
2415                                 update_log(client, zone,
2416                                            LOGLEVEL_PROTOCOL,
2417                                            "attempt to add wildcard NS record"
2418                                            "ignored");
2419                                 continue;
2420                         }
2421                         if (rdata.type == dns_rdatatype_cname) {
2422                                 CHECK(cname_incompatible_rrset_exists(db, ver,
2423                                                                       name,
2424                                                                       &flag));
2425                                 if (flag) {
2426                                         update_log(client, zone,
2427                                                    LOGLEVEL_PROTOCOL,
2428                                                    "attempt to add CNAME "
2429                                                    "alongside non-CNAME "
2430                                                    "ignored");
2431                                         continue;
2432                                 }
2433                         } else {
2434                                 CHECK(rrset_exists(db, ver, name,
2435                                                    dns_rdatatype_cname, 0,
2436                                                    &flag));
2437                                 if (flag &&
2438                                     ! dns_rdatatype_isdnssec(rdata.type))
2439                                 {
2440                                         update_log(client, zone,
2441                                                    LOGLEVEL_PROTOCOL,
2442                                                    "attempt to add non-CNAME "
2443                                                    "alongside CNAME ignored");
2444                                         continue;
2445                                 }
2446                         }
2447                         if (rdata.type == dns_rdatatype_soa) {
2448                                 isc_boolean_t ok;
2449                                 CHECK(rrset_exists(db, ver, name,
2450                                                    dns_rdatatype_soa, 0,
2451                                                    &flag));
2452                                 if (! flag) {
2453                                         update_log(client, zone,
2454                                                    LOGLEVEL_PROTOCOL,
2455                                                    "attempt to create 2nd "
2456                                                    "SOA ignored");
2457                                         continue;
2458                                 }
2459                                 CHECK(check_soa_increment(db, ver, &rdata,
2460                                                           &ok));
2461                                 if (! ok) {
2462                                         update_log(client, zone,
2463                                                    LOGLEVEL_PROTOCOL,
2464                                                    "SOA update failed to "
2465                                                    "increment serial, "
2466                                                    "ignoring it");
2467                                         continue;
2468                                 }
2469                                 soa_serial_changed = ISC_TRUE;
2470                         }
2471
2472                         if (isc_log_wouldlog(ns_g_lctx, LOGLEVEL_PROTOCOL)) {
2473                                 char namestr[DNS_NAME_FORMATSIZE];
2474                                 char typestr[DNS_RDATATYPE_FORMATSIZE];
2475                                 dns_name_format(name, namestr,
2476                                                 sizeof(namestr));
2477                                 dns_rdatatype_format(rdata.type, typestr,
2478                                                      sizeof(typestr));
2479                                 update_log(client, zone,
2480                                            LOGLEVEL_PROTOCOL,
2481                                            "adding an RR at '%s' %s",
2482                                            namestr, typestr);
2483                         }
2484
2485                         /* Prepare the affected RRset for the addition. */
2486                         {
2487                                 add_rr_prepare_ctx_t ctx;
2488                                 ctx.db = db;
2489                                 ctx.ver = ver;
2490                                 ctx.diff = &diff;
2491                                 ctx.name = name;
2492                                 ctx.update_rr = &rdata;
2493                                 ctx.update_rr_ttl = ttl;
2494                                 ctx.ignore_add = ISC_FALSE;
2495                                 dns_diff_init(mctx, &ctx.del_diff);
2496                                 dns_diff_init(mctx, &ctx.add_diff);
2497                                 CHECK(foreach_rr(db, ver, name, rdata.type,
2498                                                  covers, add_rr_prepare_action,
2499                                                  &ctx));
2500
2501                                 if (ctx.ignore_add) {
2502                                         dns_diff_clear(&ctx.del_diff);
2503                                         dns_diff_clear(&ctx.add_diff);
2504                                 } else {
2505                                         CHECK(do_diff(&ctx.del_diff, db, ver, &diff));
2506                                         CHECK(do_diff(&ctx.add_diff, db, ver, &diff));
2507                                         CHECK(update_one_rr(db, ver, &diff,
2508                                                             DNS_DIFFOP_ADD,
2509                                                             name, ttl, &rdata));
2510                                 }
2511                         }
2512                 } else if (update_class == dns_rdataclass_any) {
2513                         if (rdata.type == dns_rdatatype_any) {
2514                                 if (isc_log_wouldlog(ns_g_lctx,
2515                                                      LOGLEVEL_PROTOCOL))
2516                                 {
2517                                         char namestr[DNS_NAME_FORMATSIZE];
2518                                         dns_name_format(name, namestr,
2519                                                         sizeof(namestr));
2520                                         update_log(client, zone,
2521                                                    LOGLEVEL_PROTOCOL,
2522                                                    "delete all rrsets from "
2523                                                    "name '%s'", namestr);
2524                                 }
2525                                 if (dns_name_equal(name, zonename)) {
2526                                         CHECK(delete_if(type_not_soa_nor_ns_p,
2527                                                         db, ver, name,
2528                                                         dns_rdatatype_any, 0,
2529                                                         &rdata, &diff));
2530                                 } else {
2531                                         CHECK(delete_if(type_not_dnssec,
2532                                                         db, ver, name,
2533                                                         dns_rdatatype_any, 0,
2534                                                         &rdata, &diff));
2535                                 }
2536                         } else if (dns_name_equal(name, zonename) &&
2537                                    (rdata.type == dns_rdatatype_soa ||
2538                                     rdata.type == dns_rdatatype_ns)) {
2539                                 update_log(client, zone,
2540                                            LOGLEVEL_PROTOCOL,
2541                                            "attempt to delete all SOA "
2542                                            "or NS records ignored");
2543                                 continue;
2544                         } else {
2545                                 if (isc_log_wouldlog(ns_g_lctx,
2546                                                      LOGLEVEL_PROTOCOL))
2547                                 {
2548                                         char namestr[DNS_NAME_FORMATSIZE];
2549                                         char typestr[DNS_RDATATYPE_FORMATSIZE];
2550                                         dns_name_format(name, namestr,
2551                                                         sizeof(namestr));
2552                                         dns_rdatatype_format(rdata.type,
2553                                                              typestr,
2554                                                              sizeof(typestr));
2555                                         update_log(client, zone,
2556                                                    LOGLEVEL_PROTOCOL,
2557                                                    "deleting rrset at '%s' %s",
2558                                                    namestr, typestr);
2559                                 }
2560                                 CHECK(delete_if(true_p, db, ver, name,
2561                                                 rdata.type, covers, &rdata,
2562                                                 &diff));
2563                         }
2564                 } else if (update_class == dns_rdataclass_none) {
2565                         /*
2566                          * The (name == zonename) condition appears in
2567                          * RFC2136 3.4.2.4 but is missing from the pseudocode.
2568                          */
2569                         if (dns_name_equal(name, zonename)) {
2570                                 if (rdata.type == dns_rdatatype_soa) {
2571                                         update_log(client, zone,
2572                                                    LOGLEVEL_PROTOCOL,
2573                                                    "attempt to delete SOA "
2574                                                    "ignored");
2575                                         continue;
2576                                 }
2577                                 if (rdata.type == dns_rdatatype_ns) {
2578                                         int count;
2579                                         CHECK(rr_count(db, ver, name,
2580                                                        dns_rdatatype_ns,
2581                                                        0, &count));
2582                                         if (count == 1) {
2583                                                 update_log(client, zone,
2584                                                            LOGLEVEL_PROTOCOL,
2585                                                            "attempt to "
2586                                                            "delete last "
2587                                                            "NS ignored");
2588                                                 continue;
2589                                         }
2590                                 }
2591                         }
2592                         update_log(client, zone,
2593                                    LOGLEVEL_PROTOCOL,
2594                                    "deleting an RR");
2595                         CHECK(delete_if(rr_equal_p, db, ver, name,
2596                                         rdata.type, covers, &rdata, &diff));
2597                 }
2598         }
2599         if (result != ISC_R_NOMORE)
2600                 FAIL(result);
2601
2602         /*
2603          * If any changes were made, increment the SOA serial number,
2604          * update RRSIGs and NSECs (if zone is secure), and write the update
2605          * to the journal.
2606          */
2607         if (! ISC_LIST_EMPTY(diff.tuples)) {
2608                 char *journalfile;
2609                 dns_journal_t *journal;
2610
2611                 /*
2612                  * Increment the SOA serial, but only if it was not
2613                  * changed as a result of an update operation.
2614                  */
2615                 if (! soa_serial_changed) {
2616                         CHECK(increment_soa_serial(db, ver, &diff, mctx));
2617                 }
2618
2619                 CHECK(remove_orphaned_ds(db, ver, &diff));
2620
2621                 if (dns_db_issecure(db)) {
2622                         result = update_signatures(client, zone, db, oldver,
2623                                                    ver, &diff,
2624                                          dns_zone_getsigvalidityinterval(zone));
2625                         if (result != ISC_R_SUCCESS) {
2626                                 update_log(client, zone,
2627                                            ISC_LOG_ERROR,
2628                                            "RRSIG/NSEC update failed: %s",
2629                                            isc_result_totext(result));
2630                                 goto failure;
2631                         }
2632                 }
2633
2634                 journalfile = dns_zone_getjournal(zone);
2635                 if (journalfile != NULL) {
2636                         update_log(client, zone, LOGLEVEL_DEBUG,
2637                                    "writing journal %s", journalfile);
2638
2639                         journal = NULL;
2640                         result = dns_journal_open(mctx, journalfile,
2641                                                   ISC_TRUE, &journal);
2642                         if (result != ISC_R_SUCCESS)
2643                                 FAILS(result, "journal open failed");
2644
2645                         result = dns_journal_write_transaction(journal, &diff);
2646                         if (result != ISC_R_SUCCESS) {
2647                                 dns_journal_destroy(&journal);
2648                                 FAILS(result, "journal write failed");
2649                         }
2650
2651                         dns_journal_destroy(&journal);
2652                 }
2653
2654                 /*
2655                  * XXXRTH  Just a note that this committing code will have
2656                  *         to change to handle databases that need two-phase
2657                  *         commit, but this isn't a priority.
2658                  */
2659                 update_log(client, zone, LOGLEVEL_DEBUG,
2660                            "committing update transaction");
2661                 dns_db_closeversion(db, &ver, ISC_TRUE);
2662
2663                 /*
2664                  * Mark the zone as dirty so that it will be written to disk.
2665                  */
2666                 dns_zone_markdirty(zone);
2667
2668                 /*
2669                  * Notify slaves of the change we just made.
2670                  */
2671                 dns_zone_notify(zone);
2672         } else {
2673                 update_log(client, zone, LOGLEVEL_DEBUG, "redundant request");
2674                 dns_db_closeversion(db, &ver, ISC_TRUE);
2675         }
2676         result = ISC_R_SUCCESS;
2677         goto common;
2678
2679  failure:
2680         /*
2681          * The reason for failure should have been logged at this point.
2682          */
2683         if (ver != NULL) {
2684                 update_log(client, zone, LOGLEVEL_DEBUG,
2685                            "rolling back");
2686                 dns_db_closeversion(db, &ver, ISC_FALSE);
2687         }
2688
2689  common:
2690         dns_diff_clear(&temp);
2691         dns_diff_clear(&diff);
2692
2693         if (oldver != NULL)
2694                 dns_db_closeversion(db, &oldver, ISC_FALSE);
2695
2696         if (db != NULL)
2697                 dns_db_detach(&db);
2698
2699         if (ssutable != NULL)
2700                 dns_ssutable_detach(&ssutable);
2701
2702         if (zone != NULL)
2703                 dns_zone_detach(&zone);
2704
2705         isc_task_detach(&task);
2706         uev->result = result;
2707         uev->ev_type = DNS_EVENT_UPDATEDONE;
2708         uev->ev_action = updatedone_action;
2709         isc_task_send(client->task, &event);
2710         INSIST(event == NULL);
2711 }
2712
2713 static void
2714 updatedone_action(isc_task_t *task, isc_event_t *event) {
2715         update_event_t *uev = (update_event_t *) event;
2716         ns_client_t *client = (ns_client_t *) event->ev_arg;
2717
2718         UNUSED(task);
2719
2720         INSIST(event->ev_type == DNS_EVENT_UPDATEDONE);
2721         INSIST(task == client->task);
2722
2723         INSIST(client->nupdates > 0);
2724         client->nupdates--;
2725         respond(client, uev->result);
2726         isc_event_free(&event);
2727         ns_client_detach(&client);
2728 }
2729
2730 /*
2731  * Update forwarding support.
2732  */
2733
2734 static void
2735 forward_fail(isc_task_t *task, isc_event_t *event) {
2736         ns_client_t *client = (ns_client_t *)event->ev_arg;
2737
2738         UNUSED(task);
2739
2740         INSIST(client->nupdates > 0);
2741         client->nupdates--;
2742         respond(client, DNS_R_SERVFAIL);
2743         isc_event_free(&event);
2744         ns_client_detach(&client);
2745 }
2746
2747
2748 static void
2749 forward_callback(void *arg, isc_result_t result, dns_message_t *answer) {
2750         update_event_t *uev = arg;
2751         ns_client_t *client = uev->ev_arg;
2752
2753         if (result != ISC_R_SUCCESS) {
2754                 INSIST(answer == NULL);
2755                 uev->ev_type = DNS_EVENT_UPDATEDONE;
2756                 uev->ev_action = forward_fail;
2757         } else {
2758                 uev->ev_type = DNS_EVENT_UPDATEDONE;
2759                 uev->ev_action = forward_done;
2760                 uev->answer = answer;
2761         }
2762         isc_task_send(client->task, ISC_EVENT_PTR(&uev));
2763 }
2764
2765 static void
2766 forward_done(isc_task_t *task, isc_event_t *event) {
2767         update_event_t *uev = (update_event_t *) event;
2768         ns_client_t *client = (ns_client_t *)event->ev_arg;
2769
2770         UNUSED(task);
2771
2772         INSIST(client->nupdates > 0);
2773         client->nupdates--;
2774         ns_client_sendraw(client, uev->answer);
2775         dns_message_destroy(&uev->answer);
2776         isc_event_free(&event);
2777         ns_client_detach(&client);
2778 }
2779
2780 static void
2781 forward_action(isc_task_t *task, isc_event_t *event) {
2782         update_event_t *uev = (update_event_t *) event;
2783         dns_zone_t *zone = uev->zone;
2784         ns_client_t *client = (ns_client_t *)event->ev_arg;
2785         isc_result_t result;
2786
2787         result = dns_zone_forwardupdate(zone, client->message,
2788                                         forward_callback, event);
2789         if (result != ISC_R_SUCCESS) {
2790                 uev->ev_type = DNS_EVENT_UPDATEDONE;
2791                 uev->ev_action = forward_fail;
2792                 isc_task_send(client->task, &event);
2793         }
2794         dns_zone_detach(&zone);
2795         isc_task_detach(&task);
2796 }
2797
2798 static isc_result_t
2799 send_forward_event(ns_client_t *client, dns_zone_t *zone) {
2800         isc_result_t result = ISC_R_SUCCESS;
2801         update_event_t *event = NULL;
2802         isc_task_t *zonetask = NULL;
2803         ns_client_t *evclient;
2804
2805         event = (update_event_t *)
2806                 isc_event_allocate(client->mctx, client, DNS_EVENT_UPDATE,
2807                                    forward_action, NULL, sizeof(*event));
2808         if (event == NULL)
2809                 FAIL(ISC_R_NOMEMORY);
2810         event->zone = zone;
2811         event->result = ISC_R_SUCCESS;
2812
2813         evclient = NULL;
2814         ns_client_attach(client, &evclient);
2815         INSIST(client->nupdates == 0);
2816         client->nupdates++;
2817         event->ev_arg = evclient;
2818
2819         dns_zone_gettask(zone, &zonetask);
2820         isc_task_send(zonetask, ISC_EVENT_PTR(&event));
2821
2822  failure:
2823         if (event != NULL)
2824                 isc_event_free(ISC_EVENT_PTR(&event));
2825         return (result);
2826 }