contrib/bind9/bin/named/update.c

   1 /*
   2  * Copyright (C) 2004-2008  Internet Systems Consortium, Inc. ("ISC")
   3  * Copyright (C) 1999-2003  Internet Software Consortium.
   4  *
   5  * Permission to use, copy, modify, and/or 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 1.109.18.27 2008/02/07 03:16:08 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/keyvalues.h>
  35 #include <dns/message.h>
  36 #include <dns/nsec.h>
  37 #include <dns/rdataclass.h>
  38 #include <dns/rdataset.h>
  39 #include <dns/rdatasetiter.h>
  40 #include <dns/rdatastruct.h>
  41 #include <dns/rdatatype.h>
  42 #include <dns/soa.h>
  43 #include <dns/ssu.h>
  44 #include <dns/view.h>
  45 #include <dns/zone.h>
  46 #include <dns/zt.h>
  47
  48 #include <named/client.h>
  49 #include <named/log.h>
  50 #include <named/update.h>
  51
  52 /*! \file
  53  * \brief
  54  * This module implements dynamic update as in RFC2136.
  55  */
  56
  57 /*
  58   XXX TODO:
  59   - document strict minimality
  60 */
  61
  62 /**************************************************************************/
  63
  64 /*%
  65  * Log level for tracing dynamic update protocol requests.
  66  */
  67 #define LOGLEVEL_PROTOCOL       ISC_LOG_INFO
  68
  69 /*%
  70  * Log level for low-level debug tracing.
  71  */
  72 #define LOGLEVEL_DEBUG          ISC_LOG_DEBUG(8)
  73
  74 /*%
  75  * Check an operation for failure.  These macros all assume that
  76  * the function using them has a 'result' variable and a 'failure'
  77  * label.
  78  */
  79 #define CHECK(op) \
  80         do { result = (op);                                      \
  81                if (result != ISC_R_SUCCESS) goto failure;        \
  82         } while (0)
  83
  84 /*%
  85  * Fail unconditionally with result 'code', which must not
  86  * be ISC_R_SUCCESS.  The reason for failure presumably has
  87  * been logged already.
  88  *
  89  * The test against ISC_R_SUCCESS is there to keep the Solaris compiler
  90  * from complaining about "end-of-loop code not reached".
  91  */
  92
  93 #define FAIL(code) \
  94         do {                                                    \
  95                 result = (code);                                \
  96                 if (result != ISC_R_SUCCESS) goto failure;      \
  97         } while (0)
  98
  99 /*%
 100  * Fail unconditionally and log as a client error.
 101  * The test against ISC_R_SUCCESS is there to keep the Solaris compiler
 102  * from complaining about "end-of-loop code not reached".
 103  */
 104 #define FAILC(code, msg) \
 105         do {                                                    \
 106                 const char *_what = "failed";                   \
 107                 result = (code);                                \
 108                 switch (result) {                               \
 109                 case DNS_R_NXDOMAIN:                            \
 110                 case DNS_R_YXDOMAIN:                            \
 111                 case DNS_R_YXRRSET:                             \
 112                 case DNS_R_NXRRSET:                             \
 113                         _what = "unsuccessful";                 \
 114                 }                                               \
 115                 update_log(client, zone, LOGLEVEL_PROTOCOL,     \
 116                               "update %s: %s (%s)", _what,      \
 117                               msg, isc_result_totext(result));  \
 118                 if (result != ISC_R_SUCCESS) goto failure;      \
 119         } while (0)
 120
 121 #define FAILN(code, name, msg) \
 122         do {                                                            \
 123                 const char *_what = "failed";                           \
 124                 result = (code);                                        \
 125                 switch (result) {                                       \
 126                 case DNS_R_NXDOMAIN:                                    \
 127                 case DNS_R_YXDOMAIN:                                    \
 128                 case DNS_R_YXRRSET:                                     \
 129                 case DNS_R_NXRRSET:                                     \
 130                         _what = "unsuccessful";                         \
 131                 }                                                       \
 132                 if (isc_log_wouldlog(ns_g_lctx, LOGLEVEL_PROTOCOL)) {   \
 133                         char _nbuf[DNS_NAME_FORMATSIZE];                \
 134                         dns_name_format(name, _nbuf, sizeof(_nbuf));    \
 135                         update_log(client, zone, LOGLEVEL_PROTOCOL,     \
 136                                    "update %s: %s: %s (%s)", _what, _nbuf, \
 137                                    msg, isc_result_totext(result));     \
 138                 }                                                       \
 139                 if (result != ISC_R_SUCCESS) goto failure;              \
 140         } while (0)
 141
 142 #define FAILNT(code, name, type, msg) \
 143         do {                                                            \
 144                 const char *_what = "failed";                           \
 145                 result = (code);                                        \
 146                 switch (result) {                                       \
 147                 case DNS_R_NXDOMAIN:                                    \
 148                 case DNS_R_YXDOMAIN:                                    \
 149                 case DNS_R_YXRRSET:                                     \
 150                 case DNS_R_NXRRSET:                                     \
 151                         _what = "unsuccessful";                         \
 152                 }                                                       \
 153                 if (isc_log_wouldlog(ns_g_lctx, LOGLEVEL_PROTOCOL)) {   \
 154                         char _nbuf[DNS_NAME_FORMATSIZE];                \
 155                         char _tbuf[DNS_RDATATYPE_FORMATSIZE];           \
 156                         dns_name_format(name, _nbuf, sizeof(_nbuf));    \
 157                         dns_rdatatype_format(type, _tbuf, sizeof(_tbuf)); \
 158                         update_log(client, zone, LOGLEVEL_PROTOCOL,     \
 159                                    "update %s: %s/%s: %s (%s)",         \
 160                                    _what, _nbuf, _tbuf, msg,            \
 161                                    isc_result_totext(result));          \
 162                 }                                                       \
 163                 if (result != ISC_R_SUCCESS) goto failure;              \
 164         } while (0)
 165 /*%
 166  * Fail unconditionally and log as a server error.
 167  * The test against ISC_R_SUCCESS is there to keep the Solaris compiler
 168  * from complaining about "end-of-loop code not reached".
 169  */
 170 #define FAILS(code, msg) \
 171         do {                                                    \
 172                 result = (code);                                \
 173                 update_log(client, zone, LOGLEVEL_PROTOCOL,     \
 174                               "error: %s: %s",                  \
 175                               msg, isc_result_totext(result));  \
 176                 if (result != ISC_R_SUCCESS) goto failure;      \
 177         } while (0)
 178
 179 /**************************************************************************/
 180
 181 typedef struct rr rr_t;
 182
 183 struct rr {
 184         /* dns_name_t name; */
 185         isc_uint32_t            ttl;
 186         dns_rdata_t             rdata;
 187 };
 188
 189 typedef struct update_event update_event_t;
 190
 191 struct update_event {
 192         ISC_EVENT_COMMON(update_event_t);
 193         dns_zone_t              *zone;
 194         isc_result_t            result;
 195         dns_message_t           *answer;
 196 };
 197
 198 /**************************************************************************/
 199 /*
 200  * Forward declarations.
 201  */
 202
 203 static void update_action(isc_task_t *task, isc_event_t *event);
 204 static void updatedone_action(isc_task_t *task, isc_event_t *event);
 205 static isc_result_t send_forward_event(ns_client_t *client, dns_zone_t *zone);
 206 static void forward_done(isc_task_t *task, isc_event_t *event);
 207
 208 /**************************************************************************/
 209
 210 static void
 211 update_log(ns_client_t *client, dns_zone_t *zone,
 212            int level, const char *fmt, ...) ISC_FORMAT_PRINTF(4, 5);
 213
 214 static void
 215 update_log(ns_client_t *client, dns_zone_t *zone,
 216            int level, const char *fmt, ...)
 217 {
 218         va_list ap;
 219         char message[4096];
 220         char namebuf[DNS_NAME_FORMATSIZE];
 221         char classbuf[DNS_RDATACLASS_FORMATSIZE];
 222
 223         if (client == NULL || zone == NULL)
 224                 return;
 225
 226         if (isc_log_wouldlog(ns_g_lctx, level) == ISC_FALSE)
 227                 return;
 228
 229         dns_name_format(dns_zone_getorigin(zone), namebuf,
 230                         sizeof(namebuf));
 231         dns_rdataclass_format(dns_zone_getclass(zone), classbuf,
 232                               sizeof(classbuf));
 233
 234         va_start(ap, fmt);
 235         vsnprintf(message, sizeof(message), fmt, ap);
 236         va_end(ap);
 237
 238         ns_client_log(client, NS_LOGCATEGORY_UPDATE, NS_LOGMODULE_UPDATE,
 239                       level, "updating zone '%s/%s': %s",
 240                       namebuf, classbuf, message);
 241 }
 242
 243 static isc_result_t
 244 checkupdateacl(ns_client_t *client, dns_acl_t *acl, const char *message,
 245                dns_name_t *zonename, isc_boolean_t slave)
 246 {
 247         char namebuf[DNS_NAME_FORMATSIZE];
 248         char classbuf[DNS_RDATACLASS_FORMATSIZE];
 249         int level = ISC_LOG_ERROR;
 250         const char *msg = "denied";
 251         isc_result_t result;
 252
 253         if (slave && acl == NULL) {
 254                 result = DNS_R_NOTIMP;
 255                 level = ISC_LOG_DEBUG(3);
 256                 msg = "disabled";
 257         } else
 258                 result = ns_client_checkaclsilent(client, acl, ISC_FALSE);
 259
 260         if (result == ISC_R_SUCCESS) {
 261                 level = ISC_LOG_DEBUG(3);
 262                 msg = "approved";
 263         }
 264
 265         dns_name_format(zonename, namebuf, sizeof(namebuf));
 266         dns_rdataclass_format(client->view->rdclass, classbuf,
 267                               sizeof(classbuf));
 268
 269         ns_client_log(client, NS_LOGCATEGORY_UPDATE_SECURITY,
 270                               NS_LOGMODULE_UPDATE, level, "%s '%s/%s' %s",
 271                               message, namebuf, classbuf, msg);
 272         return (result);
 273 }
 274
 275 /*%
 276  * Update a single RR in version 'ver' of 'db' and log the
 277  * update in 'diff'.
 278  *
 279  * Ensures:
 280  * \li  '*tuple' == NULL.  Either the tuple is freed, or its
 281  *         ownership has been transferred to the diff.
 282  */
 283 static isc_result_t
 284 do_one_tuple(dns_difftuple_t **tuple,
 285              dns_db_t *db, dns_dbversion_t *ver,
 286              dns_diff_t *diff)
 287 {
 288         dns_diff_t temp_diff;
 289         isc_result_t result;
 290
 291         /*
 292          * Create a singleton diff.
 293          */
 294         dns_diff_init(diff->mctx, &temp_diff);
 295         ISC_LIST_APPEND(temp_diff.tuples, *tuple, link);
 296
 297         /*
 298          * Apply it to the database.
 299          */
 300         result = dns_diff_apply(&temp_diff, db, ver);
 301         ISC_LIST_UNLINK(temp_diff.tuples, *tuple, link);
 302         if (result != ISC_R_SUCCESS) {
 303                 dns_difftuple_free(tuple);
 304                 return (result);
 305         }
 306
 307         /*
 308          * Merge it into the current pending journal entry.
 309          */
 310         dns_diff_appendminimal(diff, tuple);
 311
 312         /*
 313          * Do not clear temp_diff.
 314          */
 315         return (ISC_R_SUCCESS);
 316 }
 317
 318 /*%
 319  * Perform the updates in 'updates' in version 'ver' of 'db' and log the
 320  * update in 'diff'.
 321  *
 322  * Ensures:
 323  * \li  'updates' is empty.
 324  */
 325 static isc_result_t
 326 do_diff(dns_diff_t *updates, dns_db_t *db, dns_dbversion_t *ver,
 327         dns_diff_t *diff)
 328 {
 329         isc_result_t result;
 330         while (! ISC_LIST_EMPTY(updates->tuples)) {
 331                 dns_difftuple_t *t = ISC_LIST_HEAD(updates->tuples);
 332                 ISC_LIST_UNLINK(updates->tuples, t, link);
 333                 CHECK(do_one_tuple(&t, db, ver, diff));
 334         }
 335         return (ISC_R_SUCCESS);
 336
 337  failure:
 338         dns_diff_clear(diff);
 339         return (result);
 340 }
 341
 342 static isc_result_t
 343 update_one_rr(dns_db_t *db, dns_dbversion_t *ver, dns_diff_t *diff,
 344               dns_diffop_t op, dns_name_t *name,
 345               dns_ttl_t ttl, dns_rdata_t *rdata)
 346 {
 347         dns_difftuple_t *tuple = NULL;
 348         isc_result_t result;
 349         result = dns_difftuple_create(diff->mctx, op,
 350                                       name, ttl, rdata, &tuple);
 351         if (result != ISC_R_SUCCESS)
 352                 return (result);
 353         return (do_one_tuple(&tuple, db, ver, diff));
 354 }
 355
 356 /**************************************************************************/
 357 /*
 358  * Callback-style iteration over rdatasets and rdatas.
 359  *
 360  * foreach_rrset() can be used to iterate over the RRsets
 361  * of a name and call a callback function with each
 362  * one.  Similarly, foreach_rr() can be used to iterate
 363  * over the individual RRs at name, optionally restricted
 364  * to RRs of a given type.
 365  *
 366  * The callback functions are called "actions" and take
 367  * two arguments: a void pointer for passing arbitrary
 368  * context information, and a pointer to the current RRset
 369  * or RR.  By convention, their names end in "_action".
 370  */
 371
 372 /*
 373  * XXXRTH  We might want to make this public somewhere in libdns.
 374  */
 375
 376 /*%
 377  * Function type for foreach_rrset() iterator actions.
 378  */
 379 typedef isc_result_t rrset_func(void *data, dns_rdataset_t *rrset);
 380
 381 /*%
 382  * Function type for foreach_rr() iterator actions.
 383  */
 384 typedef isc_result_t rr_func(void *data, rr_t *rr);
 385
 386 /*%
 387  * Internal context struct for foreach_node_rr().
 388  */
 389 typedef struct {
 390         rr_func *       rr_action;
 391         void *          rr_action_data;
 392 } foreach_node_rr_ctx_t;
 393
 394 /*%
 395  * Internal helper function for foreach_node_rr().
 396  */
 397 static isc_result_t
 398 foreach_node_rr_action(void *data, dns_rdataset_t *rdataset) {
 399         isc_result_t result;
 400         foreach_node_rr_ctx_t *ctx = data;
 401         for (result = dns_rdataset_first(rdataset);
 402              result == ISC_R_SUCCESS;
 403              result = dns_rdataset_next(rdataset))
 404         {
 405                 rr_t rr = { 0, DNS_RDATA_INIT };
 406
 407                 dns_rdataset_current(rdataset, &rr.rdata);
 408                 rr.ttl = rdataset->ttl;
 409                 result = (*ctx->rr_action)(ctx->rr_action_data, &rr);
 410                 if (result != ISC_R_SUCCESS)
 411                         return (result);
 412         }
 413         if (result != ISC_R_NOMORE)
 414                 return (result);
 415         return (ISC_R_SUCCESS);
 416 }
 417
 418 /*%
 419  * For each rdataset of 'name' in 'ver' of 'db', call 'action'
 420  * with the rdataset and 'action_data' as arguments.  If the name
 421  * does not exist, do nothing.
 422  *
 423  * If 'action' returns an error, abort iteration and return the error.
 424  */
 425 static isc_result_t
 426 foreach_rrset(dns_db_t *db,
 427               dns_dbversion_t *ver,
 428               dns_name_t *name,
 429               rrset_func *action,
 430               void *action_data)
 431 {
 432         isc_result_t result;
 433         dns_dbnode_t *node;
 434         dns_rdatasetiter_t *iter;
 435
 436         node = NULL;
 437         result = dns_db_findnode(db, name, ISC_FALSE, &node);
 438         if (result == ISC_R_NOTFOUND)
 439                 return (ISC_R_SUCCESS);
 440         if (result != ISC_R_SUCCESS)
 441                 return (result);
 442
 443         iter = NULL;
 444         result = dns_db_allrdatasets(db, node, ver,
 445                                      (isc_stdtime_t) 0, &iter);
 446         if (result != ISC_R_SUCCESS)
 447                 goto cleanup_node;
 448
 449         for (result = dns_rdatasetiter_first(iter);
 450              result == ISC_R_SUCCESS;
 451              result = dns_rdatasetiter_next(iter))
 452         {
 453                 dns_rdataset_t rdataset;
 454
 455                 dns_rdataset_init(&rdataset);
 456                 dns_rdatasetiter_current(iter, &rdataset);
 457
 458                 result = (*action)(action_data, &rdataset);
 459
 460                 dns_rdataset_disassociate(&rdataset);
 461                 if (result != ISC_R_SUCCESS)
 462                         goto cleanup_iterator;
 463         }
 464         if (result == ISC_R_NOMORE)
 465                 result = ISC_R_SUCCESS;
 466
 467  cleanup_iterator:
 468         dns_rdatasetiter_destroy(&iter);
 469
 470  cleanup_node:
 471         dns_db_detachnode(db, &node);
 472
 473         return (result);
 474 }
 475
 476 /*%
 477  * For each RR of 'name' in 'ver' of 'db', call 'action'
 478  * with the RR and 'action_data' as arguments.  If the name
 479  * does not exist, do nothing.
 480  *
 481  * If 'action' returns an error, abort iteration
 482  * and return the error.
 483  */
 484 static isc_result_t
 485 foreach_node_rr(dns_db_t *db,
 486             dns_dbversion_t *ver,
 487             dns_name_t *name,
 488             rr_func *rr_action,
 489             void *rr_action_data)
 490 {
 491         foreach_node_rr_ctx_t ctx;
 492         ctx.rr_action = rr_action;
 493         ctx.rr_action_data = rr_action_data;
 494         return (foreach_rrset(db, ver, name,
 495                               foreach_node_rr_action, &ctx));
 496 }
 497
 498
 499 /*%
 500  * For each of the RRs specified by 'db', 'ver', 'name', 'type',
 501  * (which can be dns_rdatatype_any to match any type), and 'covers', call
 502  * 'action' with the RR and 'action_data' as arguments. If the name
 503  * does not exist, or if no RRset of the given type exists at the name,
 504  * do nothing.
 505  *
 506  * If 'action' returns an error, abort iteration and return the error.
 507  */
 508 static isc_result_t
 509 foreach_rr(dns_db_t *db,
 510            dns_dbversion_t *ver,
 511            dns_name_t *name,
 512            dns_rdatatype_t type,
 513            dns_rdatatype_t covers,
 514            rr_func *rr_action,
 515            void *rr_action_data)
 516 {
 517
 518         isc_result_t result;
 519         dns_dbnode_t *node;
 520         dns_rdataset_t rdataset;
 521
 522         if (type == dns_rdatatype_any)
 523                 return (foreach_node_rr(db, ver, name,
 524                                         rr_action, rr_action_data));
 525
 526         node = NULL;
 527         result = dns_db_findnode(db, name, ISC_FALSE, &node);
 528         if (result == ISC_R_NOTFOUND)
 529                 return (ISC_R_SUCCESS);
 530         if (result != ISC_R_SUCCESS)
 531                 return (result);
 532
 533         dns_rdataset_init(&rdataset);
 534         result = dns_db_findrdataset(db, node, ver, type, covers,
 535                                      (isc_stdtime_t) 0, &rdataset, NULL);
 536         if (result == ISC_R_NOTFOUND) {
 537                 result = ISC_R_SUCCESS;
 538                 goto cleanup_node;
 539         }
 540         if (result != ISC_R_SUCCESS)
 541                 goto cleanup_node;
 542
 543         for (result = dns_rdataset_first(&rdataset);
 544              result == ISC_R_SUCCESS;
 545              result = dns_rdataset_next(&rdataset))
 546         {
 547                 rr_t rr = { 0, DNS_RDATA_INIT };
 548                 dns_rdataset_current(&rdataset, &rr.rdata);
 549                 rr.ttl = rdataset.ttl;
 550                 result = (*rr_action)(rr_action_data, &rr);
 551                 if (result != ISC_R_SUCCESS)
 552                         goto cleanup_rdataset;
 553         }
 554         if (result != ISC_R_NOMORE)
 555                 goto cleanup_rdataset;
 556         result = ISC_R_SUCCESS;
 557
 558  cleanup_rdataset:
 559         dns_rdataset_disassociate(&rdataset);
 560  cleanup_node:
 561         dns_db_detachnode(db, &node);
 562
 563         return (result);
 564 }
 565
 566 /**************************************************************************/
 567 /*
 568  * Various tests on the database contents (for prerequisites, etc).
 569  */
 570
 571 /*%
 572  * Function type for predicate functions that compare a database RR 'db_rr'
 573  * against an update RR 'update_rr'.
 574  */
 575 typedef isc_boolean_t rr_predicate(dns_rdata_t *update_rr, dns_rdata_t *db_rr);
 576
 577 /*%
 578  * Helper function for rrset_exists().
 579  */
 580 static isc_result_t
 581 rrset_exists_action(void *data, rr_t *rr) {
 582         UNUSED(data);
 583         UNUSED(rr);
 584         return (ISC_R_EXISTS);
 585 }
 586
 587 /*%
 588  * Utility macro for RR existence checking functions.
 589  *
 590  * If the variable 'result' has the value ISC_R_EXISTS or
 591  * ISC_R_SUCCESS, set *exists to ISC_TRUE or ISC_FALSE,
 592  * respectively, and return success.
 593  *
 594  * If 'result' has any other value, there was a failure.
 595  * Return the failure result code and do not set *exists.
 596  *
 597  * This would be more readable as "do { if ... } while(0)",
 598  * but that form generates tons of warnings on Solaris 2.6.
 599  */
 600 #define RETURN_EXISTENCE_FLAG                           \
 601         return ((result == ISC_R_EXISTS) ?              \
 602                 (*exists = ISC_TRUE, ISC_R_SUCCESS) :   \
 603                 ((result == ISC_R_SUCCESS) ?            \
 604                  (*exists = ISC_FALSE, ISC_R_SUCCESS) : \
 605                  result))
 606
 607 /*%
 608  * Set '*exists' to true iff an rrset of the given type exists,
 609  * to false otherwise.
 610  */
 611 static isc_result_t
 612 rrset_exists(dns_db_t *db, dns_dbversion_t *ver,
 613              dns_name_t *name, dns_rdatatype_t type, dns_rdatatype_t covers,
 614              isc_boolean_t *exists)
 615 {
 616         isc_result_t result;
 617         result = foreach_rr(db, ver, name, type, covers,
 618                             rrset_exists_action, NULL);
 619         RETURN_EXISTENCE_FLAG;
 620 }
 621
 622 /*%
 623  * Helper function for cname_incompatible_rrset_exists.
 624  */
 625 static isc_result_t
 626 cname_compatibility_action(void *data, dns_rdataset_t *rrset) {
 627         UNUSED(data);
 628         if (rrset->type != dns_rdatatype_cname &&
 629             ! dns_rdatatype_isdnssec(rrset->type))
 630                 return (ISC_R_EXISTS);
 631         return (ISC_R_SUCCESS);
 632 }
 633
 634 /*%
 635  * Check whether there is an rrset incompatible with adding a CNAME RR,
 636  * i.e., anything but another CNAME (which can be replaced) or a
 637  * DNSSEC RR (which can coexist).
 638  *
 639  * If such an incompatible rrset exists, set '*exists' to ISC_TRUE.
 640  * Otherwise, set it to ISC_FALSE.
 641  */
 642 static isc_result_t
 643 cname_incompatible_rrset_exists(dns_db_t *db, dns_dbversion_t *ver,
 644                                 dns_name_t *name, isc_boolean_t *exists) {
 645         isc_result_t result;
 646         result = foreach_rrset(db, ver, name,
 647                                cname_compatibility_action, NULL);
 648         RETURN_EXISTENCE_FLAG;
 649 }
 650
 651 /*%
 652  * Helper function for rr_count().
 653  */
 654 static isc_result_t
 655 count_rr_action(void *data, rr_t *rr) {
 656         int *countp = data;
 657         UNUSED(rr);
 658         (*countp)++;
 659         return (ISC_R_SUCCESS);
 660 }
 661
 662 /*%
 663  * Count the number of RRs of 'type' belonging to 'name' in 'ver' of 'db'.
 664  */
 665 static isc_result_t
 666 rr_count(dns_db_t *db, dns_dbversion_t *ver, dns_name_t *name,
 667          dns_rdatatype_t type, dns_rdatatype_t covers, int *countp)
 668 {
 669         *countp = 0;
 670         return (foreach_rr(db, ver, name, type, covers,
 671                            count_rr_action, countp));
 672 }
 673
 674 /*%
 675  * Context struct and helper function for name_exists().
 676  */
 677
 678 static isc_result_t
 679 name_exists_action(void *data, dns_rdataset_t *rrset) {
 680         UNUSED(data);
 681         UNUSED(rrset);
 682         return (ISC_R_EXISTS);
 683 }
 684
 685 /*%
 686  * Set '*exists' to true iff the given name exists, to false otherwise.
 687  */
 688 static isc_result_t
 689 name_exists(dns_db_t *db, dns_dbversion_t *ver, dns_name_t *name,
 690             isc_boolean_t *exists)
 691 {
 692         isc_result_t result;
 693         result = foreach_rrset(db, ver, name,
 694                                name_exists_action, NULL);
 695         RETURN_EXISTENCE_FLAG;
 696 }
 697
 698 typedef struct {
 699         dns_name_t *name, *signer;
 700         dns_ssutable_t *table;
 701 } ssu_check_t;
 702
 703 static isc_result_t
 704 ssu_checkrule(void *data, dns_rdataset_t *rrset) {
 705         ssu_check_t *ssuinfo = data;
 706         isc_boolean_t result;
 707
 708         /*
 709          * If we're deleting all records, it's ok to delete RRSIG and NSEC even
 710          * if we're normally not allowed to.
 711          */
 712         if (rrset->type == dns_rdatatype_rrsig ||
 713             rrset->type == dns_rdatatype_nsec)
 714                 return (ISC_R_SUCCESS);
 715         result = dns_ssutable_checkrules(ssuinfo->table, ssuinfo->signer,
 716                                          ssuinfo->name, rrset->type);
 717         return (result == ISC_TRUE ? ISC_R_SUCCESS : ISC_R_FAILURE);
 718 }
 719
 720 static isc_boolean_t
 721 ssu_checkall(dns_db_t *db, dns_dbversion_t *ver, dns_name_t *name,
 722              dns_ssutable_t *ssutable, dns_name_t *signer)
 723 {
 724         isc_result_t result;
 725         ssu_check_t ssuinfo;
 726
 727         ssuinfo.name = name;
 728         ssuinfo.table = ssutable;
 729         ssuinfo.signer = signer;
 730         result = foreach_rrset(db, ver, name, ssu_checkrule, &ssuinfo);
 731         return (ISC_TF(result == ISC_R_SUCCESS));
 732 }
 733
 734 /**************************************************************************/
 735 /*
 736  * Checking of "RRset exists (value dependent)" prerequisites.
 737  *
 738  * In the RFC2136 section 3.2.5, this is the pseudocode involving
 739  * a variable called "temp", a mapping of <name, type> tuples to rrsets.
 740  *
 741  * Here, we represent the "temp" data structure as (non-minimial) "dns_diff_t"
 742  * where each typle has op==DNS_DIFFOP_EXISTS.
 743  */
 744
 745
 746 /*%
 747  * Append a tuple asserting the existence of the RR with
 748  * 'name' and 'rdata' to 'diff'.
 749  */
 750 static isc_result_t
 751 temp_append(dns_diff_t *diff, dns_name_t *name, dns_rdata_t *rdata) {
 752         isc_result_t result;
 753         dns_difftuple_t *tuple = NULL;
 754
 755         REQUIRE(DNS_DIFF_VALID(diff));
 756         CHECK(dns_difftuple_create(diff->mctx, DNS_DIFFOP_EXISTS,
 757                                       name, 0, rdata, &tuple));
 758         ISC_LIST_APPEND(diff->tuples, tuple, link);
 759  failure:
 760         return (result);
 761 }
 762
 763 /*%
 764  * Compare two rdatasets represented as sorted lists of tuples.
 765  * All list elements must have the same owner name and type.
 766  * Return ISC_R_SUCCESS if the rdatasets are equal, rcode(dns_rcode_nxrrset)
 767  * if not.
 768  */
 769 static isc_result_t
 770 temp_check_rrset(dns_difftuple_t *a, dns_difftuple_t *b) {
 771         for (;;) {
 772                 if (a == NULL || b == NULL)
 773                         break;
 774                 INSIST(a->op == DNS_DIFFOP_EXISTS &&
 775                        b->op == DNS_DIFFOP_EXISTS);
 776                 INSIST(a->rdata.type == b->rdata.type);
 777                 INSIST(dns_name_equal(&a->name, &b->name));
 778                 if (dns_rdata_compare(&a->rdata, &b->rdata) != 0)
 779                         return (DNS_R_NXRRSET);
 780                 a = ISC_LIST_NEXT(a, link);
 781                 b = ISC_LIST_NEXT(b, link);
 782         }
 783         if (a != NULL || b != NULL)
 784                 return (DNS_R_NXRRSET);
 785         return (ISC_R_SUCCESS);
 786 }
 787
 788 /*%
 789  * A comparison function defining the sorting order for the entries
 790  * in the "temp" data structure.  The major sort key is the owner name,
 791  * followed by the type and rdata.
 792  */
 793 static int
 794 temp_order(const void *av, const void *bv) {
 795         dns_difftuple_t const * const *ap = av;
 796         dns_difftuple_t const * const *bp = bv;
 797         dns_difftuple_t const *a = *ap;
 798         dns_difftuple_t const *b = *bp;
 799         int r;
 800         r = dns_name_compare(&a->name, &b->name);
 801         if (r != 0)
 802                 return (r);
 803         r = (b->rdata.type - a->rdata.type);
 804         if (r != 0)
 805                 return (r);
 806         r = dns_rdata_compare(&a->rdata, &b->rdata);
 807         return (r);
 808 }
 809
 810 /*%
 811  * Check the "RRset exists (value dependent)" prerequisite information
 812  * in 'temp' against the contents of the database 'db'.
 813  *
 814  * Return ISC_R_SUCCESS if the prerequisites are satisfied,
 815  * rcode(dns_rcode_nxrrset) if not.
 816  *
 817  * 'temp' must be pre-sorted.
 818  */
 819
 820 static isc_result_t
 821 temp_check(isc_mem_t *mctx, dns_diff_t *temp, dns_db_t *db,
 822            dns_dbversion_t *ver, dns_name_t *tmpname, dns_rdatatype_t *typep)
 823 {
 824         isc_result_t result;
 825         dns_name_t *name;
 826         dns_dbnode_t *node;
 827         dns_difftuple_t *t;
 828         dns_diff_t trash;
 829
 830         dns_diff_init(mctx, &trash);
 831
 832         /*
 833          * For each name and type in the prerequisites,
 834          * construct a sorted rdata list of the corresponding
 835          * database contents, and compare the lists.
 836          */
 837         t = ISC_LIST_HEAD(temp->tuples);
 838         while (t != NULL) {
 839                 name = &t->name;
 840                 (void)dns_name_copy(name, tmpname, NULL);
 841                 *typep = t->rdata.type;
 842
 843                 /* A new unique name begins here. */
 844                 node = NULL;
 845                 result = dns_db_findnode(db, name, ISC_FALSE, &node);
 846                 if (result == ISC_R_NOTFOUND) {
 847                         dns_diff_clear(&trash);
 848                         return (DNS_R_NXRRSET);
 849                 }
 850                 if (result != ISC_R_SUCCESS) {
 851                         dns_diff_clear(&trash);
 852                         return (result);
 853                 }
 854
 855                 /* A new unique type begins here. */
 856                 while (t != NULL && dns_name_equal(&t->name, name)) {
 857                         dns_rdatatype_t type, covers;
 858                         dns_rdataset_t rdataset;
 859                         dns_diff_t d_rrs; /* Database RRs with
 860                                                 this name and type */
 861                         dns_diff_t u_rrs; /* Update RRs with
 862                                                 this name and type */
 863
 864                         *typep = type = t->rdata.type;
 865                         if (type == dns_rdatatype_rrsig ||
 866                             type == dns_rdatatype_sig)
 867                                 covers = dns_rdata_covers(&t->rdata);
 868                         else
 869                                 covers = 0;
 870
 871                         /*
 872                          * Collect all database RRs for this name and type
 873                          * onto d_rrs and sort them.
 874                          */
 875                         dns_rdataset_init(&rdataset);
 876                         result = dns_db_findrdataset(db, node, ver, type,
 877                                                      covers, (isc_stdtime_t) 0,
 878                                                      &rdataset, NULL);
 879                         if (result != ISC_R_SUCCESS) {
 880                                 dns_db_detachnode(db, &node);
 881                                 dns_diff_clear(&trash);
 882                                 return (DNS_R_NXRRSET);
 883                         }
 884
 885                         dns_diff_init(mctx, &d_rrs);
 886                         dns_diff_init(mctx, &u_rrs);
 887
 888                         for (result = dns_rdataset_first(&rdataset);
 889                              result == ISC_R_SUCCESS;
 890                              result = dns_rdataset_next(&rdataset))
 891                         {
 892                                 dns_rdata_t rdata = DNS_RDATA_INIT;
 893                                 dns_rdataset_current(&rdataset, &rdata);
 894                                 result = temp_append(&d_rrs, name, &rdata);
 895                                 if (result != ISC_R_SUCCESS)
 896                                         goto failure;
 897                         }
 898                         if (result != ISC_R_NOMORE)
 899                                 goto failure;
 900                         result = dns_diff_sort(&d_rrs, temp_order);
 901                         if (result != ISC_R_SUCCESS)
 902                                 goto failure;
 903
 904                         /*
 905                          * Collect all update RRs for this name and type
 906                          * onto u_rrs.  No need to sort them here -
 907                          * they are already sorted.
 908                          */
 909                         while (t != NULL &&
 910                                dns_name_equal(&t->name, name) &&
 911                                t->rdata.type == type)
 912                         {
 913                                 dns_difftuple_t *next =
 914                                         ISC_LIST_NEXT(t, link);
 915                                 ISC_LIST_UNLINK(temp->tuples, t, link);
 916                                 ISC_LIST_APPEND(u_rrs.tuples, t, link);
 917                                 t = next;
 918                         }
 919
 920                         /* Compare the two sorted lists. */
 921                         result = temp_check_rrset(ISC_LIST_HEAD(u_rrs.tuples),
 922                                                   ISC_LIST_HEAD(d_rrs.tuples));
 923                         if (result != ISC_R_SUCCESS)
 924                                 goto failure;
 925
 926                         /*
 927                          * We are done with the tuples, but we can't free
 928                          * them yet because "name" still points into one
 929                          * of them.  Move them on a temporary list.
 930                          */
 931                         ISC_LIST_APPENDLIST(trash.tuples, u_rrs.tuples, link);
 932                         ISC_LIST_APPENDLIST(trash.tuples, d_rrs.tuples, link);
 933                         dns_rdataset_disassociate(&rdataset);
 934
 935                         continue;
 936
 937                     failure:
 938                         dns_diff_clear(&d_rrs);
 939                         dns_diff_clear(&u_rrs);
 940                         dns_diff_clear(&trash);
 941                         dns_rdataset_disassociate(&rdataset);
 942                         dns_db_detachnode(db, &node);
 943                         return (result);
 944                 }
 945
 946                 dns_db_detachnode(db, &node);
 947         }
 948
 949         dns_diff_clear(&trash);
 950         return (ISC_R_SUCCESS);
 951 }
 952
 953 /**************************************************************************/
 954 /*
 955  * Conditional deletion of RRs.
 956  */
 957
 958 /*%
 959  * Context structure for delete_if().
 960  */
 961
 962 typedef struct {
 963         rr_predicate *predicate;
 964         dns_db_t *db;
 965         dns_dbversion_t *ver;
 966         dns_diff_t *diff;
 967         dns_name_t *name;
 968         dns_rdata_t *update_rr;
 969 } conditional_delete_ctx_t;
 970
 971 /*%
 972  * Predicate functions for delete_if().
 973  */
 974
 975 /*%
 976  * Return true iff 'db_rr' is neither a SOA nor an NS RR nor
 977  * an RRSIG nor a NSEC.
 978  */
 979 static isc_boolean_t
 980 type_not_soa_nor_ns_p(dns_rdata_t *update_rr, dns_rdata_t *db_rr) {
 981         UNUSED(update_rr);
 982         return ((db_rr->type != dns_rdatatype_soa &&
 983                  db_rr->type != dns_rdatatype_ns &&
 984                  db_rr->type != dns_rdatatype_rrsig &&
 985                  db_rr->type != dns_rdatatype_nsec) ?
 986                 ISC_TRUE : ISC_FALSE);
 987 }
 988
 989 /*%
 990  * Return true iff 'db_rr' is neither a RRSIG nor a NSEC.
 991  */
 992 static isc_boolean_t
 993 type_not_dnssec(dns_rdata_t *update_rr, dns_rdata_t *db_rr) {
 994         UNUSED(update_rr);
 995         return ((db_rr->type != dns_rdatatype_rrsig &&
 996                  db_rr->type != dns_rdatatype_nsec) ?
 997                 ISC_TRUE : ISC_FALSE);
 998 }
 999
1000 /*%
1001  * Return true always.
1002  */
1003 static isc_boolean_t
1004 true_p(dns_rdata_t *update_rr, dns_rdata_t *db_rr) {
1005         UNUSED(update_rr);
1006         UNUSED(db_rr);
1007         return (ISC_TRUE);
1008 }
1009
1010 /*%
1011  * Return true iff the two RRs have identical rdata.
1012  */
1013 static isc_boolean_t
1014 rr_equal_p(dns_rdata_t *update_rr, dns_rdata_t *db_rr) {
1015         /*
1016          * XXXRTH  This is not a problem, but we should consider creating
1017          *         dns_rdata_equal() (that used dns_name_equal()), since it
1018          *         would be faster.  Not a priority.
1019          */
1020         return (dns_rdata_compare(update_rr, db_rr) == 0 ?
1021                 ISC_TRUE : ISC_FALSE);
1022 }
1023
1024 /*%
1025  * Return true iff 'update_rr' should replace 'db_rr' according
1026  * to the special RFC2136 rules for CNAME, SOA, and WKS records.
1027  *
1028  * RFC2136 does not mention NSEC or DNAME, but multiple NSECs or DNAMEs
1029  * make little sense, so we replace those, too.
1030  */
1031 static isc_boolean_t
1032 replaces_p(dns_rdata_t *update_rr, dns_rdata_t *db_rr) {
1033         if (db_rr->type != update_rr->type)
1034                 return (ISC_FALSE);
1035         if (db_rr->type == dns_rdatatype_cname)
1036                 return (ISC_TRUE);
1037         if (db_rr->type == dns_rdatatype_dname)
1038                 return (ISC_TRUE);
1039         if (db_rr->type == dns_rdatatype_soa)
1040                 return (ISC_TRUE);
1041         if (db_rr->type == dns_rdatatype_nsec)
1042                 return (ISC_TRUE);
1043         if (db_rr->type == dns_rdatatype_wks) {
1044                 /*
1045                  * Compare the address and protocol fields only.  These
1046                  * form the first five bytes of the RR data.  Do a
1047                  * raw binary comparison; unpacking the WKS RRs using
1048                  * dns_rdata_tostruct() might be cleaner in some ways,
1049                  * but it would require us to pass around an mctx.
1050                  */
1051                 INSIST(db_rr->length >= 5 && update_rr->length >= 5);
1052                 return (memcmp(db_rr->data, update_rr->data, 5) == 0 ?
1053                         ISC_TRUE : ISC_FALSE);
1054         }
1055         return (ISC_FALSE);
1056 }
1057
1058 /*%
1059  * Internal helper function for delete_if().
1060  */
1061 static isc_result_t
1062 delete_if_action(void *data, rr_t *rr) {
1063         conditional_delete_ctx_t *ctx = data;
1064         if ((*ctx->predicate)(ctx->update_rr, &rr->rdata)) {
1065                 isc_result_t result;
1066                 result = update_one_rr(ctx->db, ctx->ver, ctx->diff,
1067                                        DNS_DIFFOP_DEL, ctx->name,
1068                                        rr->ttl, &rr->rdata);
1069                 return (result);
1070         } else {
1071                 return (ISC_R_SUCCESS);
1072         }
1073 }
1074
1075 /*%
1076  * Conditionally delete RRs.  Apply 'predicate' to the RRs
1077  * specified by 'db', 'ver', 'name', and 'type' (which can
1078  * be dns_rdatatype_any to match any type).  Delete those
1079  * RRs for which the predicate returns true, and log the
1080  * deletions in 'diff'.
1081  */
1082 static isc_result_t
1083 delete_if(rr_predicate *predicate,
1084           dns_db_t *db,
1085           dns_dbversion_t *ver,
1086           dns_name_t *name,
1087           dns_rdatatype_t type,
1088           dns_rdatatype_t covers,
1089           dns_rdata_t *update_rr,
1090           dns_diff_t *diff)
1091 {
1092         conditional_delete_ctx_t ctx;
1093         ctx.predicate = predicate;
1094         ctx.db = db;
1095         ctx.ver = ver;
1096         ctx.diff = diff;
1097         ctx.name = name;
1098         ctx.update_rr = update_rr;
1099         return (foreach_rr(db, ver, name, type, covers,
1100                            delete_if_action, &ctx));
1101 }
1102
1103 /**************************************************************************/
1104 /*%
1105  * Prepare an RR for the addition of the new RR 'ctx->update_rr',
1106  * with TTL 'ctx->update_rr_ttl', to its rdataset, by deleting
1107  * the RRs if it is replaced by the new RR or has a conflicting TTL.
1108  * The necessary changes are appended to ctx->del_diff and ctx->add_diff;
1109  * we need to do all deletions before any additions so that we don't run
1110  * into transient states with conflicting TTLs.
1111  */
1112
1113 typedef struct {
1114         dns_db_t *db;
1115         dns_dbversion_t *ver;
1116         dns_diff_t *diff;
1117         dns_name_t *name;
1118         dns_rdata_t *update_rr;
1119         dns_ttl_t update_rr_ttl;
1120         isc_boolean_t ignore_add;
1121         dns_diff_t del_diff;
1122         dns_diff_t add_diff;
1123 } add_rr_prepare_ctx_t;
1124
1125 static isc_result_t
1126 add_rr_prepare_action(void *data, rr_t *rr) {
1127         isc_result_t result = ISC_R_SUCCESS;
1128         add_rr_prepare_ctx_t *ctx = data;
1129         dns_difftuple_t *tuple = NULL;
1130         isc_boolean_t equal;
1131
1132         /*
1133          * If the update RR is a "duplicate" of the update RR,
1134          * the update should be silently ignored.
1135          */
1136         equal = ISC_TF(dns_rdata_compare(&rr->rdata, ctx->update_rr) == 0);
1137         if (equal && rr->ttl == ctx->update_rr_ttl) {
1138                 ctx->ignore_add = ISC_TRUE;
1139                 return (ISC_R_SUCCESS);
1140         }
1141
1142         /*
1143          * If this RR is "equal" to the update RR, it should
1144          * be deleted before the update RR is added.
1145          */
1146         if (replaces_p(ctx->update_rr, &rr->rdata)) {
1147                 CHECK(dns_difftuple_create(ctx->del_diff.mctx,
1148                                            DNS_DIFFOP_DEL, ctx->name,
1149                                            rr->ttl,
1150                                            &rr->rdata,
1151                                            &tuple));
1152                 dns_diff_append(&ctx->del_diff, &tuple);
1153                 return (ISC_R_SUCCESS);
1154         }
1155
1156         /*
1157          * If this RR differs in TTL from the update RR,
1158          * its TTL must be adjusted.
1159          */
1160         if (rr->ttl != ctx->update_rr_ttl) {
1161                 CHECK(dns_difftuple_create(ctx->del_diff.mctx,
1162                                            DNS_DIFFOP_DEL, ctx->name,
1163                                            rr->ttl,
1164                                            &rr->rdata,
1165                                            &tuple));
1166                 dns_diff_append(&ctx->del_diff, &tuple);
1167                 if (!equal) {
1168                         CHECK(dns_difftuple_create(ctx->add_diff.mctx,
1169                                                    DNS_DIFFOP_ADD, ctx->name,
1170                                                    ctx->update_rr_ttl,
1171                                                    &rr->rdata,
1172                                                    &tuple));
1173                         dns_diff_append(&ctx->add_diff, &tuple);
1174                 }
1175         }
1176  failure:
1177         return (result);
1178 }
1179
1180 /**************************************************************************/
1181 /*
1182  * Miscellaneous subroutines.
1183  */
1184
1185 /*%
1186  * Extract a single update RR from 'section' of dynamic update message
1187  * 'msg', with consistency checking.
1188  *
1189  * Stores the owner name, rdata, and TTL of the update RR at 'name',
1190  * 'rdata', and 'ttl', respectively.
1191  */
1192 static void
1193 get_current_rr(dns_message_t *msg, dns_section_t section,
1194                dns_rdataclass_t zoneclass,
1195                dns_name_t **name, dns_rdata_t *rdata, dns_rdatatype_t *covers,
1196                dns_ttl_t *ttl,
1197                dns_rdataclass_t *update_class)
1198 {
1199         dns_rdataset_t *rdataset;
1200         isc_result_t result;
1201         dns_message_currentname(msg, section, name);
1202         rdataset = ISC_LIST_HEAD((*name)->list);
1203         INSIST(rdataset != NULL);
1204         INSIST(ISC_LIST_NEXT(rdataset, link) == NULL);
1205         *covers = rdataset->covers;
1206         *ttl = rdataset->ttl;
1207         result = dns_rdataset_first(rdataset);
1208         INSIST(result == ISC_R_SUCCESS);
1209         dns_rdataset_current(rdataset, rdata);
1210         INSIST(dns_rdataset_next(rdataset) == ISC_R_NOMORE);
1211         *update_class = rdata->rdclass;
1212         rdata->rdclass = zoneclass;
1213 }
1214
1215 /*%
1216  * Increment the SOA serial number of database 'db', version 'ver'.
1217  * Replace the SOA record in the database, and log the
1218  * change in 'diff'.
1219  */
1220
1221         /*
1222          * XXXRTH  Failures in this routine will be worth logging, when
1223          *         we have a logging system.  Failure to find the zonename
1224          *         or the SOA rdataset warrant at least an UNEXPECTED_ERROR().
1225          */
1226
1227 static isc_result_t
1228 increment_soa_serial(dns_db_t *db, dns_dbversion_t *ver,
1229                      dns_diff_t *diff, isc_mem_t *mctx)
1230 {
1231         dns_difftuple_t *deltuple = NULL;
1232         dns_difftuple_t *addtuple = NULL;
1233         isc_uint32_t serial;
1234         isc_result_t result;
1235
1236         CHECK(dns_db_createsoatuple(db, ver, mctx, DNS_DIFFOP_DEL, &deltuple));
1237         CHECK(dns_difftuple_copy(deltuple, &addtuple));
1238         addtuple->op = DNS_DIFFOP_ADD;
1239
1240         serial = dns_soa_getserial(&addtuple->rdata);
1241
1242         /* RFC1982 */
1243         serial = (serial + 1) & 0xFFFFFFFF;
1244         if (serial == 0)
1245                 serial = 1;
1246
1247         dns_soa_setserial(serial, &addtuple->rdata);
1248         CHECK(do_one_tuple(&deltuple, db, ver, diff));
1249         CHECK(do_one_tuple(&addtuple, db, ver, diff));
1250         result = ISC_R_SUCCESS;
1251
1252  failure:
1253         if (addtuple != NULL)
1254                 dns_difftuple_free(&addtuple);
1255         if (deltuple != NULL)
1256                 dns_difftuple_free(&deltuple);
1257         return (result);
1258 }
1259
1260 /*%
1261  * Check that the new SOA record at 'update_rdata' does not
1262  * illegally cause the SOA serial number to decrease or stay
1263  * unchanged relative to the existing SOA in 'db'.
1264  *
1265  * Sets '*ok' to ISC_TRUE if the update is legal, ISC_FALSE if not.
1266  *
1267  * William King points out that RFC2136 is inconsistent about
1268  * the case where the serial number stays unchanged:
1269  *
1270  *   section 3.4.2.2 requires a server to ignore a SOA update request
1271  *   if the serial number on the update SOA is less_than_or_equal to
1272  *   the zone SOA serial.
1273  *
1274  *   section 3.6 requires a server to ignore a SOA update request if
1275  *   the serial is less_than the zone SOA serial.
1276  *
1277  * Paul says 3.4.2.2 is correct.
1278  *
1279  */
1280 static isc_result_t
1281 check_soa_increment(dns_db_t *db, dns_dbversion_t *ver,
1282                     dns_rdata_t *update_rdata,
1283                     isc_boolean_t *ok)
1284 {
1285         isc_uint32_t db_serial;
1286         isc_uint32_t update_serial;
1287         isc_result_t result;
1288
1289         update_serial = dns_soa_getserial(update_rdata);
1290
1291         result = dns_db_getsoaserial(db, ver, &db_serial);
1292         if (result != ISC_R_SUCCESS)
1293                 return (result);
1294
1295         if (DNS_SERIAL_GE(db_serial, update_serial)) {
1296                 *ok = ISC_FALSE;
1297         } else {
1298                 *ok = ISC_TRUE;
1299         }
1300
1301         return (ISC_R_SUCCESS);
1302
1303 }
1304
1305 /**************************************************************************/
1306 /*
1307  * Incremental updating of NSECs and RRSIGs.
1308  */
1309
1310 #define MAXZONEKEYS 32  /*%< Maximum number of zone keys supported. */
1311
1312 /*%
1313  * We abuse the dns_diff_t type to represent a set of domain names
1314  * affected by the update.
1315  */
1316 static isc_result_t
1317 namelist_append_name(dns_diff_t *list, dns_name_t *name) {
1318         isc_result_t result;
1319         dns_difftuple_t *tuple = NULL;
1320         static dns_rdata_t dummy_rdata = DNS_RDATA_INIT;
1321
1322         CHECK(dns_difftuple_create(list->mctx, DNS_DIFFOP_EXISTS, name, 0,
1323                                    &dummy_rdata, &tuple));
1324         dns_diff_append(list, &tuple);
1325  failure:
1326         return (result);
1327 }
1328
1329 static isc_result_t
1330 namelist_append_subdomain(dns_db_t *db, dns_name_t *name, dns_diff_t *affected)
1331 {
1332         isc_result_t result;
1333         dns_fixedname_t fixedname;
1334         dns_name_t *child;
1335         dns_dbiterator_t *dbit = NULL;
1336
1337         dns_fixedname_init(&fixedname);
1338         child = dns_fixedname_name(&fixedname);
1339
1340         CHECK(dns_db_createiterator(db, ISC_FALSE, &dbit));
1341
1342         for (result = dns_dbiterator_seek(dbit, name);
1343              result == ISC_R_SUCCESS;
1344              result = dns_dbiterator_next(dbit))
1345         {
1346                 dns_dbnode_t *node = NULL;
1347                 CHECK(dns_dbiterator_current(dbit, &node, child));
1348                 dns_db_detachnode(db, &node);
1349                 if (! dns_name_issubdomain(child, name))
1350                         break;
1351                 CHECK(namelist_append_name(affected, child));
1352         }
1353         if (result == ISC_R_NOMORE)
1354                 result = ISC_R_SUCCESS;
1355  failure:
1356         if (dbit != NULL)
1357                 dns_dbiterator_destroy(&dbit);
1358         return (result);
1359 }
1360
1361
1362
1363 /*%
1364  * Helper function for non_nsec_rrset_exists().
1365  */
1366 static isc_result_t
1367 is_non_nsec_action(void *data, dns_rdataset_t *rrset) {
1368         UNUSED(data);
1369         if (!(rrset->type == dns_rdatatype_nsec ||
1370               (rrset->type == dns_rdatatype_rrsig &&
1371                rrset->covers == dns_rdatatype_nsec)))
1372                 return (ISC_R_EXISTS);
1373         return (ISC_R_SUCCESS);
1374 }
1375
1376 /*%
1377  * Check whether there is an rrset other than a NSEC or RRSIG NSEC,
1378  * i.e., anything that justifies the continued existence of a name
1379  * after a secure update.
1380  *
1381  * If such an rrset exists, set '*exists' to ISC_TRUE.
1382  * Otherwise, set it to ISC_FALSE.
1383  */
1384 static isc_result_t
1385 non_nsec_rrset_exists(dns_db_t *db, dns_dbversion_t *ver,
1386                      dns_name_t *name, isc_boolean_t *exists)
1387 {
1388         isc_result_t result;
1389         result = foreach_rrset(db, ver, name,
1390                                is_non_nsec_action, NULL);
1391         RETURN_EXISTENCE_FLAG;
1392 }
1393
1394 /*%
1395  * A comparison function for sorting dns_diff_t:s by name.
1396  */
1397 static int
1398 name_order(const void *av, const void *bv) {
1399         dns_difftuple_t const * const *ap = av;
1400         dns_difftuple_t const * const *bp = bv;
1401         dns_difftuple_t const *a = *ap;
1402         dns_difftuple_t const *b = *bp;
1403         return (dns_name_compare(&a->name, &b->name));
1404 }
1405
1406 static isc_result_t
1407 uniqify_name_list(dns_diff_t *list) {
1408         isc_result_t result;
1409         dns_difftuple_t *p, *q;
1410
1411         CHECK(dns_diff_sort(list, name_order));
1412
1413         p = ISC_LIST_HEAD(list->tuples);
1414         while (p != NULL) {
1415                 do {
1416                         q = ISC_LIST_NEXT(p, link);
1417                         if (q == NULL || ! dns_name_equal(&p->name, &q->name))
1418                                 break;
1419                         ISC_LIST_UNLINK(list->tuples, q, link);
1420                         dns_difftuple_free(&q);
1421                 } while (1);
1422                 p = ISC_LIST_NEXT(p, link);
1423         }
1424  failure:
1425         return (result);
1426 }
1427
1428
1429 static isc_result_t
1430 is_glue(dns_db_t *db, dns_dbversion_t *ver, dns_name_t *name,
1431         isc_boolean_t *flag)
1432 {
1433         isc_result_t result;
1434         dns_fixedname_t foundname;
1435         dns_fixedname_init(&foundname);
1436         result = dns_db_find(db, name, ver, dns_rdatatype_any,
1437                              DNS_DBFIND_GLUEOK | DNS_DBFIND_NOWILD,
1438                              (isc_stdtime_t) 0, NULL,
1439                              dns_fixedname_name(&foundname),
1440                              NULL, NULL);
1441         if (result == ISC_R_SUCCESS) {
1442                 *flag = ISC_FALSE;
1443                 return (ISC_R_SUCCESS);
1444         } else if (result == DNS_R_ZONECUT) {
1445                 /*
1446                  * We are at the zonecut.  The name will have an NSEC, but
1447                  * non-delegation will be omitted from the type bit map.
1448                  */
1449                 *flag = ISC_FALSE;
1450                 return (ISC_R_SUCCESS);
1451         } else if (result == DNS_R_GLUE || result == DNS_R_DNAME) {
1452                 *flag = ISC_TRUE;
1453                 return (ISC_R_SUCCESS);
1454         } else {
1455                 return (result);
1456         }
1457 }
1458
1459 /*%
1460  * Find the next/previous name that has a NSEC record.
1461  * In other words, skip empty database nodes and names that
1462  * have had their NSECs removed because they are obscured by
1463  * a zone cut.
1464  */
1465 static isc_result_t
1466 next_active(ns_client_t *client, dns_zone_t *zone, dns_db_t *db,
1467             dns_dbversion_t *ver, dns_name_t *oldname, dns_name_t *newname,
1468             isc_boolean_t forward)
1469 {
1470         isc_result_t result;
1471         dns_dbiterator_t *dbit = NULL;
1472         isc_boolean_t has_nsec;
1473         unsigned int wraps = 0;
1474
1475         CHECK(dns_db_createiterator(db, ISC_FALSE, &dbit));
1476
1477         CHECK(dns_dbiterator_seek(dbit, oldname));
1478         do {
1479                 dns_dbnode_t *node = NULL;
1480
1481                 if (forward)
1482                         result = dns_dbiterator_next(dbit);
1483                 else
1484                         result = dns_dbiterator_prev(dbit);
1485                 if (result == ISC_R_NOMORE) {
1486                         /*
1487                          * Wrap around.
1488                          */
1489                         if (forward)
1490                                 CHECK(dns_dbiterator_first(dbit));
1491                         else
1492                                 CHECK(dns_dbiterator_last(dbit));
1493                         wraps++;
1494                         if (wraps == 2) {
1495                                 update_log(client, zone, ISC_LOG_ERROR,
1496                                            "secure zone with no NSECs");
1497                                 result = DNS_R_BADZONE;
1498                                 goto failure;
1499                         }
1500                 }
1501                 CHECK(dns_dbiterator_current(dbit, &node, newname));
1502                 dns_db_detachnode(db, &node);
1503
1504                 /*
1505                  * The iterator may hold the tree lock, and
1506                  * rrset_exists() calls dns_db_findnode() which
1507                  * may try to reacquire it.  To avoid deadlock
1508                  * we must pause the iterator first.
1509                  */
1510                 CHECK(dns_dbiterator_pause(dbit));
1511                 CHECK(rrset_exists(db, ver, newname,
1512                                    dns_rdatatype_nsec, 0, &has_nsec));
1513
1514         } while (! has_nsec);
1515  failure:
1516         if (dbit != NULL)
1517                 dns_dbiterator_destroy(&dbit);
1518
1519         return (result);
1520 }
1521
1522 /*%
1523  * Add a NSEC record for "name", recording the change in "diff".
1524  * The existing NSEC is removed.
1525  */
1526 static isc_result_t
1527 add_nsec(ns_client_t *client, dns_zone_t *zone, dns_db_t *db,
1528          dns_dbversion_t *ver, dns_name_t *name, dns_ttl_t nsecttl,
1529          dns_diff_t *diff)
1530 {
1531         isc_result_t result;
1532         dns_dbnode_t *node = NULL;
1533         unsigned char buffer[DNS_NSEC_BUFFERSIZE];
1534         dns_rdata_t rdata = DNS_RDATA_INIT;
1535         dns_difftuple_t *tuple = NULL;
1536         dns_fixedname_t fixedname;
1537         dns_name_t *target;
1538
1539         dns_fixedname_init(&fixedname);
1540         target = dns_fixedname_name(&fixedname);
1541
1542         /*
1543          * Find the successor name, aka NSEC target.
1544          */
1545         CHECK(next_active(client, zone, db, ver, name, target, ISC_TRUE));
1546
1547         /*
1548          * Create the NSEC RDATA.
1549          */
1550         CHECK(dns_db_findnode(db, name, ISC_FALSE, &node));
1551         dns_rdata_init(&rdata);
1552         CHECK(dns_nsec_buildrdata(db, ver, node, target, buffer, &rdata));
1553         dns_db_detachnode(db, &node);
1554
1555         /*
1556          * Delete the old NSEC and record the change.
1557          */
1558         CHECK(delete_if(true_p, db, ver, name, dns_rdatatype_nsec, 0,
1559                         NULL, diff));
1560         /*
1561          * Add the new NSEC and record the change.
1562          */
1563         CHECK(dns_difftuple_create(diff->mctx, DNS_DIFFOP_ADD, name,
1564                                    nsecttl, &rdata, &tuple));
1565         CHECK(do_one_tuple(&tuple, db, ver, diff));
1566         INSIST(tuple == NULL);
1567
1568  failure:
1569         if (node != NULL)
1570                 dns_db_detachnode(db, &node);
1571         return (result);
1572 }
1573
1574 /*%
1575  * Add a placeholder NSEC record for "name", recording the change in "diff".
1576  */
1577 static isc_result_t
1578 add_placeholder_nsec(dns_db_t *db, dns_dbversion_t *ver, dns_name_t *name,
1579                     dns_diff_t *diff) {
1580         isc_result_t result;
1581         dns_difftuple_t *tuple = NULL;
1582         isc_region_t r;
1583         unsigned char data[1] = { 0 }; /* The root domain, no bits. */
1584         dns_rdata_t rdata = DNS_RDATA_INIT;
1585
1586         r.base = data;
1587         r.length = sizeof(data);
1588         dns_rdata_fromregion(&rdata, dns_db_class(db), dns_rdatatype_nsec, &r);
1589         CHECK(dns_difftuple_create(diff->mctx, DNS_DIFFOP_ADD, name, 0,
1590                                    &rdata, &tuple));
1591         CHECK(do_one_tuple(&tuple, db, ver, diff));
1592  failure:
1593         return (result);
1594 }
1595
1596 static isc_result_t
1597 find_zone_keys(dns_zone_t *zone, dns_db_t *db, dns_dbversion_t *ver,
1598                isc_mem_t *mctx, unsigned int maxkeys,
1599                dst_key_t **keys, unsigned int *nkeys)
1600 {
1601         isc_result_t result;
1602         dns_dbnode_t *node = NULL;
1603         const char *directory = dns_zone_getkeydirectory(zone);
1604         CHECK(dns_db_findnode(db, dns_db_origin(db), ISC_FALSE, &node));
1605         CHECK(dns_dnssec_findzonekeys2(db, ver, node, dns_db_origin(db),
1606                                        directory, mctx, maxkeys, keys, nkeys));
1607  failure:
1608         if (node != NULL)
1609                 dns_db_detachnode(db, &node);
1610         return (result);
1611 }
1612
1613 static isc_boolean_t
1614 ksk_sanity(dns_db_t *db, dns_dbversion_t *ver) {
1615         isc_boolean_t ret = ISC_FALSE;
1616         isc_boolean_t have_ksk = ISC_FALSE, have_nonksk = ISC_FALSE;
1617         isc_result_t result;
1618         dns_dbnode_t *node = NULL;
1619         dns_rdataset_t rdataset;
1620         dns_rdata_t rdata = DNS_RDATA_INIT;
1621         dns_rdata_dnskey_t dnskey;
1622
1623         dns_rdataset_init(&rdataset);
1624         CHECK(dns_db_findnode(db, dns_db_origin(db), ISC_FALSE, &node));
1625         CHECK(dns_db_findrdataset(db, node, ver, dns_rdatatype_dnskey, 0, 0,
1626                                    &rdataset, NULL));
1627         CHECK(dns_rdataset_first(&rdataset));
1628         while (result == ISC_R_SUCCESS && (!have_ksk || !have_nonksk)) {
1629                 dns_rdataset_current(&rdataset, &rdata);
1630                 CHECK(dns_rdata_tostruct(&rdata, &dnskey, NULL));
1631                 if ((dnskey.flags & (DNS_KEYFLAG_OWNERMASK|DNS_KEYTYPE_NOAUTH))
1632                                  == DNS_KEYOWNER_ZONE) {
1633                         if ((dnskey.flags & DNS_KEYFLAG_KSK) != 0)
1634                                 have_ksk = ISC_TRUE;
1635                         else
1636                                 have_nonksk = ISC_TRUE;
1637                 }
1638                 dns_rdata_reset(&rdata);
1639                 result = dns_rdataset_next(&rdataset);
1640         }
1641         if (have_ksk && have_nonksk)
1642                 ret = ISC_TRUE;
1643  failure:
1644         if (dns_rdataset_isassociated(&rdataset))
1645                 dns_rdataset_disassociate(&rdataset);
1646         if (node != NULL)
1647                 dns_db_detachnode(db, &node);
1648         return (ret);
1649 }
1650
1651 /*%
1652  * Add RRSIG records for an RRset, recording the change in "diff".
1653  */
1654 static isc_result_t
1655 add_sigs(ns_client_t *client, dns_zone_t *zone, dns_db_t *db,
1656          dns_dbversion_t *ver, dns_name_t *name, dns_rdatatype_t type,
1657          dns_diff_t *diff, dst_key_t **keys, unsigned int nkeys,
1658          isc_mem_t *mctx, isc_stdtime_t inception, isc_stdtime_t expire,
1659          isc_boolean_t check_ksk)
1660 {
1661         isc_result_t result;
1662         dns_dbnode_t *node = NULL;
1663         dns_rdataset_t rdataset;
1664         dns_rdata_t sig_rdata = DNS_RDATA_INIT;
1665         isc_buffer_t buffer;
1666         unsigned char data[1024]; /* XXX */
1667         unsigned int i;
1668         isc_boolean_t added_sig = ISC_FALSE;
1669
1670         dns_rdataset_init(&rdataset);
1671         isc_buffer_init(&buffer, data, sizeof(data));
1672
1673         /* Get the rdataset to sign. */
1674         CHECK(dns_db_findnode(db, name, ISC_FALSE, &node));
1675         CHECK(dns_db_findrdataset(db, node, ver, type, 0,
1676                                   (isc_stdtime_t) 0,
1677                                   &rdataset, NULL));
1678         dns_db_detachnode(db, &node);
1679
1680         for (i = 0; i < nkeys; i++) {
1681
1682                 if (check_ksk && type != dns_rdatatype_dnskey &&
1683                     (dst_key_flags(keys[i]) & DNS_KEYFLAG_KSK) != 0)
1684                         continue;
1685
1686                 if (!dst_key_isprivate(keys[i]))
1687                         continue;
1688
1689                 /* Calculate the signature, creating a RRSIG RDATA. */
1690                 CHECK(dns_dnssec_sign(name, &rdataset, keys[i],
1691                                       &inception, &expire,
1692                                       mctx, &buffer, &sig_rdata));
1693
1694                 /* Update the database and journal with the RRSIG. */
1695                 /* XXX inefficient - will cause dataset merging */
1696                 CHECK(update_one_rr(db, ver, diff, DNS_DIFFOP_ADD, name,
1697                                     rdataset.ttl, &sig_rdata));
1698                 dns_rdata_reset(&sig_rdata);
1699                 added_sig = ISC_TRUE;
1700         }
1701         if (!added_sig) {
1702                 update_log(client, zone, ISC_LOG_ERROR,
1703                            "found no private keys, "
1704                            "unable to generate any signatures");
1705                 result = ISC_R_NOTFOUND;
1706         }
1707
1708  failure:
1709         if (dns_rdataset_isassociated(&rdataset))
1710                 dns_rdataset_disassociate(&rdataset);
1711         if (node != NULL)
1712                 dns_db_detachnode(db, &node);
1713         return (result);
1714 }
1715
1716 /*%
1717  * Update RRSIG and NSEC records affected by an update.  The original
1718  * update, including the SOA serial update but exluding the RRSIG & NSEC
1719  * changes, is in "diff" and has already been applied to "newver" of "db".
1720  * The database version prior to the update is "oldver".
1721  *
1722  * The necessary RRSIG and NSEC changes will be applied to "newver"
1723  * and added (as a minimal diff) to "diff".
1724  *
1725  * The RRSIGs generated will be valid for 'sigvalidityinterval' seconds.
1726  */
1727 static isc_result_t
1728 update_signatures(ns_client_t *client, dns_zone_t *zone, dns_db_t *db,
1729                   dns_dbversion_t *oldver, dns_dbversion_t *newver,
1730                   dns_diff_t *diff, isc_uint32_t sigvalidityinterval)
1731 {
1732         isc_result_t result;
1733         dns_difftuple_t *t;
1734         dns_diff_t diffnames;
1735         dns_diff_t affected;
1736         dns_diff_t sig_diff;
1737         dns_diff_t nsec_diff;
1738         dns_diff_t nsec_mindiff;
1739         isc_boolean_t flag;
1740         dst_key_t *zone_keys[MAXZONEKEYS];
1741         unsigned int nkeys = 0;
1742         unsigned int i;
1743         isc_stdtime_t now, inception, expire;
1744         dns_ttl_t nsecttl;
1745         dns_rdata_soa_t soa;
1746         dns_rdata_t rdata = DNS_RDATA_INIT;
1747         dns_rdataset_t rdataset;
1748         dns_dbnode_t *node = NULL;
1749         isc_boolean_t check_ksk;
1750
1751         dns_diff_init(client->mctx, &diffnames);
1752         dns_diff_init(client->mctx, &affected);
1753
1754         dns_diff_init(client->mctx, &sig_diff);
1755         dns_diff_init(client->mctx, &nsec_diff);
1756         dns_diff_init(client->mctx, &nsec_mindiff);
1757
1758         result = find_zone_keys(zone, db, newver, client->mctx,
1759                                 MAXZONEKEYS, zone_keys, &nkeys);
1760         if (result != ISC_R_SUCCESS) {
1761                 update_log(client, zone, ISC_LOG_ERROR,
1762                            "could not get zone keys for secure dynamic update");
1763                 goto failure;
1764         }
1765
1766         isc_stdtime_get(&now);
1767         inception = now - 3600; /* Allow for some clock skew. */
1768         expire = now + sigvalidityinterval;
1769
1770         /*
1771          * Do we look at the KSK flag on the DNSKEY to determining which
1772          * keys sign which RRsets?  First check the zone option then
1773          * check the keys flags to make sure atleast one has a ksk set
1774          * and one doesn't.
1775          */
1776         check_ksk = ISC_TF((dns_zone_getoptions(zone) &
1777                             DNS_ZONEOPT_UPDATECHECKKSK) != 0);
1778         if (check_ksk)
1779                 check_ksk = ksk_sanity(db, newver);
1780
1781         /*
1782          * Get the NSEC's TTL from the SOA MINIMUM field.
1783          */
1784         CHECK(dns_db_findnode(db, dns_db_origin(db), ISC_FALSE, &node));
1785         dns_rdataset_init(&rdataset);
1786         CHECK(dns_db_findrdataset(db, node, newver, dns_rdatatype_soa, 0,
1787                                   (isc_stdtime_t) 0, &rdataset, NULL));
1788         CHECK(dns_rdataset_first(&rdataset));
1789         dns_rdataset_current(&rdataset, &rdata);
1790         CHECK(dns_rdata_tostruct(&rdata, &soa, NULL));
1791         nsecttl = soa.minimum;
1792         dns_rdataset_disassociate(&rdataset);
1793         dns_db_detachnode(db, &node);
1794
1795         /*
1796          * Find all RRsets directly affected by the update, and
1797          * update their RRSIGs.  Also build a list of names affected
1798          * by the update in "diffnames".
1799          */
1800         CHECK(dns_diff_sort(diff, temp_order));
1801
1802         t = ISC_LIST_HEAD(diff->tuples);
1803         while (t != NULL) {
1804                 dns_name_t *name = &t->name;
1805                 /* Now "name" is a new, unique name affected by the update. */
1806
1807                 CHECK(namelist_append_name(&diffnames, name));
1808
1809                 while (t != NULL && dns_name_equal(&t->name, name)) {
1810                         dns_rdatatype_t type;
1811                         type = t->rdata.type;
1812
1813                         /*
1814                          * Now "name" and "type" denote a new unique RRset
1815                          * affected by the update.
1816                          */
1817
1818                         /* Don't sign RRSIGs. */
1819                         if (type == dns_rdatatype_rrsig)
1820                                 goto skip;
1821
1822                         /*
1823                          * Delete all old RRSIGs covering this type, since they
1824                          * are all invalid when the signed RRset has changed.
1825                          * We may not be able to recreate all of them - tough.
1826                          */
1827                         CHECK(delete_if(true_p, db, newver, name,
1828                                         dns_rdatatype_rrsig, type,
1829                                         NULL, &sig_diff));
1830
1831                         /*
1832                          * If this RRset still exists after the update,
1833                          * add a new signature for it.
1834                          */
1835                         CHECK(rrset_exists(db, newver, name, type, 0, &flag));
1836                         if (flag) {
1837                                 CHECK(add_sigs(client, zone, db, newver, name,
1838                                                type, &sig_diff, zone_keys,
1839                                                nkeys, client->mctx, inception,
1840                                                expire, check_ksk));
1841                         }
1842                 skip:
1843                         /* Skip any other updates to the same RRset. */
1844                         while (t != NULL &&
1845                                dns_name_equal(&t->name, name) &&
1846                                t->rdata.type == type)
1847                         {
1848                                 t = ISC_LIST_NEXT(t, link);
1849                         }
1850                 }
1851         }
1852
1853         /* Remove orphaned NSECs and RRSIG NSECs. */
1854         for (t = ISC_LIST_HEAD(diffnames.tuples);
1855              t != NULL;
1856              t = ISC_LIST_NEXT(t, link))
1857         {
1858                 CHECK(non_nsec_rrset_exists(db, newver, &t->name, &flag));
1859                 if (! flag) {
1860                         CHECK(delete_if(true_p, db, newver, &t->name,
1861                                         dns_rdatatype_any, 0,
1862                                         NULL, &sig_diff));
1863                 }
1864         }
1865
1866         /*
1867          * When a name is created or deleted, its predecessor needs to
1868          * have its NSEC updated.
1869          */
1870         for (t = ISC_LIST_HEAD(diffnames.tuples);
1871              t != NULL;
1872              t = ISC_LIST_NEXT(t, link))
1873         {
1874                 isc_boolean_t existed, exists;
1875                 dns_fixedname_t fixedname;
1876                 dns_name_t *prevname;
1877
1878                 dns_fixedname_init(&fixedname);
1879                 prevname = dns_fixedname_name(&fixedname);
1880
1881                 CHECK(name_exists(db, oldver, &t->name, &existed));
1882                 CHECK(name_exists(db, newver, &t->name, &exists));
1883                 if (exists == existed)
1884                         continue;
1885
1886                 /*
1887                  * Find the predecessor.
1888                  * When names become obscured or unobscured in this update
1889                  * transaction, we may find the wrong predecessor because
1890                  * the NSECs have not yet been updated to reflect the delegation
1891                  * change.  This should not matter because in this case,
1892                  * the correct predecessor is either the delegation node or
1893                  * a newly unobscured node, and those nodes are on the
1894                  * "affected" list in any case.
1895                  */
1896                 CHECK(next_active(client, zone, db, newver,
1897                                   &t->name, prevname, ISC_FALSE));
1898                 CHECK(namelist_append_name(&affected, prevname));
1899         }
1900
1901         /*
1902          * Find names potentially affected by delegation changes
1903          * (obscured by adding an NS or DNAME, or unobscured by
1904          * removing one).
1905          */
1906         for (t = ISC_LIST_HEAD(diffnames.tuples);
1907              t != NULL;
1908              t = ISC_LIST_NEXT(t, link))
1909         {
1910                 isc_boolean_t ns_existed, dname_existed;
1911                 isc_boolean_t ns_exists, dname_exists;
1912
1913                 CHECK(rrset_exists(db, oldver, &t->name, dns_rdatatype_ns, 0,
1914                                    &ns_existed));
1915                 CHECK(rrset_exists(db, oldver, &t->name, dns_rdatatype_dname, 0,
1916                                    &dname_existed));
1917                 CHECK(rrset_exists(db, newver, &t->name, dns_rdatatype_ns, 0,
1918                                    &ns_exists));
1919                 CHECK(rrset_exists(db, newver, &t->name, dns_rdatatype_dname, 0,
1920                                    &dname_exists));
1921                 if ((ns_exists || dname_exists) == (ns_existed || dname_existed))
1922                         continue;
1923                 /*
1924                  * There was a delegation change.  Mark all subdomains
1925                  * of t->name as potentially needing a NSEC update.
1926                  */
1927                 CHECK(namelist_append_subdomain(db, &t->name, &affected));
1928         }
1929
1930         ISC_LIST_APPENDLIST(affected.tuples, diffnames.tuples, link);
1931         INSIST(ISC_LIST_EMPTY(diffnames.tuples));
1932
1933         CHECK(uniqify_name_list(&affected));
1934
1935         /*
1936          * Determine which names should have NSECs, and delete/create
1937          * NSECs to make it so.  We don't know the final NSEC targets yet,
1938          * so we just create placeholder NSECs with arbitrary contents
1939          * to indicate that their respective owner names should be part of
1940          * the NSEC chain.
1941          */
1942         for (t = ISC_LIST_HEAD(affected.tuples);
1943              t != NULL;
1944              t = ISC_LIST_NEXT(t, link))
1945         {
1946                 isc_boolean_t exists;
1947                 CHECK(name_exists(db, newver, &t->name, &exists));
1948                 if (! exists)
1949                         continue;
1950                 CHECK(is_glue(db, newver, &t->name, &flag));
1951                 if (flag) {
1952                         /*
1953                          * This name is obscured.  Delete any
1954                          * existing NSEC record.
1955                          */
1956                         CHECK(delete_if(true_p, db, newver, &t->name,
1957                                         dns_rdatatype_nsec, 0,
1958                                         NULL, &nsec_diff));
1959                 } else {
1960                         /*
1961                          * This name is not obscured.  It should have a NSEC.
1962                          */
1963                         CHECK(rrset_exists(db, newver, &t->name,
1964                                            dns_rdatatype_nsec, 0, &flag));
1965                         if (! flag)
1966                                 CHECK(add_placeholder_nsec(db, newver, &t->name,
1967                                                           diff));
1968                 }
1969         }
1970
1971         /*
1972          * Now we know which names are part of the NSEC chain.
1973          * Make them all point at their correct targets.
1974          */
1975         for (t = ISC_LIST_HEAD(affected.tuples);
1976              t != NULL;
1977              t = ISC_LIST_NEXT(t, link))
1978         {
1979                 CHECK(rrset_exists(db, newver, &t->name,
1980                                    dns_rdatatype_nsec, 0, &flag));
1981                 if (flag) {
1982                         /*
1983                          * There is a NSEC, but we don't know if it is correct.
1984                          * Delete it and create a correct one to be sure.
1985                          * If the update was unnecessary, the diff minimization
1986                          * will take care of eliminating it from the journal,
1987                          * IXFRs, etc.
1988                          *
1989                          * The RRSIG bit should always be set in the NSECs
1990                          * we generate, because they will all get RRSIG NSECs.
1991                          * (XXX what if the zone keys are missing?).
1992                          * Because the RRSIG NSECs have not necessarily been
1993                          * created yet, the correctness of the bit mask relies
1994                          * on the assumption that NSECs are only created if
1995                          * there is other data, and if there is other data,
1996                          * there are other RRSIGs.
1997                          */
1998                         CHECK(add_nsec(client, zone, db, newver, &t->name,
1999                                        nsecttl, &nsec_diff));
2000                 }
2001         }
2002
2003         /*
2004          * Minimize the set of NSEC updates so that we don't
2005          * have to regenerate the RRSIG NSECs for NSECs that were
2006          * replaced with identical ones.
2007          */
2008         while ((t = ISC_LIST_HEAD(nsec_diff.tuples)) != NULL) {
2009                 ISC_LIST_UNLINK(nsec_diff.tuples, t, link);
2010                 dns_diff_appendminimal(&nsec_mindiff, &t);
2011         }
2012
2013         /* Update RRSIG NSECs. */
2014         for (t = ISC_LIST_HEAD(nsec_mindiff.tuples);
2015              t != NULL;
2016              t = ISC_LIST_NEXT(t, link))
2017         {
2018                 if (t->op == DNS_DIFFOP_DEL) {
2019                         CHECK(delete_if(true_p, db, newver, &t->name,
2020                                         dns_rdatatype_rrsig, dns_rdatatype_nsec,
2021                                         NULL, &sig_diff));
2022                 } else if (t->op == DNS_DIFFOP_ADD) {
2023                         CHECK(add_sigs(client, zone, db, newver, &t->name,
2024                                        dns_rdatatype_nsec, &sig_diff,
2025                                        zone_keys, nkeys, client->mctx,
2026                                        inception, expire, check_ksk));
2027                 } else {
2028                         INSIST(0);
2029                 }
2030         }
2031
2032         /* Record our changes for the journal. */
2033         while ((t = ISC_LIST_HEAD(sig_diff.tuples)) != NULL) {
2034                 ISC_LIST_UNLINK(sig_diff.tuples, t, link);
2035                 dns_diff_appendminimal(diff, &t);
2036         }
2037         while ((t = ISC_LIST_HEAD(nsec_mindiff.tuples)) != NULL) {
2038                 ISC_LIST_UNLINK(nsec_mindiff.tuples, t, link);
2039                 dns_diff_appendminimal(diff, &t);
2040         }
2041
2042         INSIST(ISC_LIST_EMPTY(sig_diff.tuples));
2043         INSIST(ISC_LIST_EMPTY(nsec_diff.tuples));
2044         INSIST(ISC_LIST_EMPTY(nsec_mindiff.tuples));
2045
2046  failure:
2047         dns_diff_clear(&sig_diff);
2048         dns_diff_clear(&nsec_diff);
2049         dns_diff_clear(&nsec_mindiff);
2050
2051         dns_diff_clear(&affected);
2052         dns_diff_clear(&diffnames);
2053
2054         for (i = 0; i < nkeys; i++)
2055                 dst_key_free(&zone_keys[i]);
2056
2057         return (result);
2058 }
2059
2060
2061 /**************************************************************************/
2062 /*%
2063  * The actual update code in all its glory.  We try to follow
2064  * the RFC2136 pseudocode as closely as possible.
2065  */
2066
2067 static isc_result_t
2068 send_update_event(ns_client_t *client, dns_zone_t *zone) {
2069         isc_result_t result = ISC_R_SUCCESS;
2070         update_event_t *event = NULL;
2071         isc_task_t *zonetask = NULL;
2072         ns_client_t *evclient;
2073
2074         event = (update_event_t *)
2075                 isc_event_allocate(client->mctx, client, DNS_EVENT_UPDATE,
2076                                    update_action, NULL, sizeof(*event));
2077         if (event == NULL)
2078                 FAIL(ISC_R_NOMEMORY);
2079         event->zone = zone;
2080         event->result = ISC_R_SUCCESS;
2081
2082         evclient = NULL;
2083         ns_client_attach(client, &evclient);
2084         INSIST(client->nupdates == 0);
2085         client->nupdates++;
2086         event->ev_arg = evclient;
2087
2088         dns_zone_gettask(zone, &zonetask);
2089         isc_task_send(zonetask, ISC_EVENT_PTR(&event));
2090
2091  failure:
2092         if (event != NULL)
2093                 isc_event_free(ISC_EVENT_PTR(&event));
2094         return (result);
2095 }
2096
2097 static void
2098 respond(ns_client_t *client, isc_result_t result) {
2099         isc_result_t msg_result;
2100
2101         msg_result = dns_message_reply(client->message, ISC_TRUE);
2102         if (msg_result != ISC_R_SUCCESS)
2103                 goto msg_failure;
2104         client->message->rcode = dns_result_torcode(result);
2105
2106         ns_client_send(client);
2107         return;
2108
2109  msg_failure:
2110         isc_log_write(ns_g_lctx, NS_LOGCATEGORY_UPDATE, NS_LOGMODULE_UPDATE,
2111                       ISC_LOG_ERROR,
2112                       "could not create update response message: %s",
2113                       isc_result_totext(msg_result));
2114         ns_client_next(client, msg_result);
2115 }
2116
2117 void
2118 ns_update_start(ns_client_t *client, isc_result_t sigresult) {
2119         dns_message_t *request = client->message;
2120         isc_result_t result;
2121         dns_name_t *zonename;
2122         dns_rdataset_t *zone_rdataset;
2123         dns_zone_t *zone = NULL;
2124
2125         /*
2126          * Interpret the zone section.
2127          */
2128         result = dns_message_firstname(request, DNS_SECTION_ZONE);
2129         if (result != ISC_R_SUCCESS)
2130                 FAILC(DNS_R_FORMERR,
2131                       "update zone section empty");
2132
2133         /*
2134          * The zone section must contain exactly one "question", and
2135          * it must be of type SOA.
2136          */
2137         zonename = NULL;
2138         dns_message_currentname(request, DNS_SECTION_ZONE, &zonename);
2139         zone_rdataset = ISC_LIST_HEAD(zonename->list);
2140         if (zone_rdataset->type != dns_rdatatype_soa)
2141                 FAILC(DNS_R_FORMERR,
2142                       "update zone section contains non-SOA");
2143         if (ISC_LIST_NEXT(zone_rdataset, link) != NULL)
2144                 FAILC(DNS_R_FORMERR,
2145                       "update zone section contains multiple RRs");
2146
2147         /* The zone section must have exactly one name. */
2148         result = dns_message_nextname(request, DNS_SECTION_ZONE);
2149         if (result != ISC_R_NOMORE)
2150                 FAILC(DNS_R_FORMERR,
2151                       "update zone section contains multiple RRs");
2152
2153         result = dns_zt_find(client->view->zonetable, zonename, 0, NULL,
2154                              &zone);
2155         if (result != ISC_R_SUCCESS)
2156                 FAILC(DNS_R_NOTAUTH,
2157                       "not authoritative for update zone");
2158
2159         switch(dns_zone_gettype(zone)) {
2160         case dns_zone_master:
2161                 /*
2162                  * We can now fail due to a bad signature as we now know
2163                  * that we are the master.
2164                  */
2165                 if (sigresult != ISC_R_SUCCESS)
2166                         FAIL(sigresult);
2167                 CHECK(send_update_event(client, zone));
2168                 break;
2169         case dns_zone_slave:
2170                 CHECK(checkupdateacl(client, dns_zone_getforwardacl(zone),
2171                                      "update forwarding", zonename, ISC_TRUE));
2172                 CHECK(send_forward_event(client, zone));
2173                 break;
2174         default:
2175                 FAILC(DNS_R_NOTAUTH,
2176                       "not authoritative for update zone");
2177         }
2178         return;
2179
2180  failure:
2181         /*
2182          * We failed without having sent an update event to the zone.
2183          * We are still in the client task context, so we can
2184          * simply give an error response without switching tasks.
2185          */
2186         respond(client, result);
2187         if (zone != NULL)
2188                 dns_zone_detach(&zone);
2189 }
2190
2191 /*%
2192  * DS records are not allowed to exist without corresponding NS records,
2193  * draft-ietf-dnsext-delegation-signer-11.txt, 2.2 Protocol Change,
2194  * "DS RRsets MUST NOT appear at non-delegation points or at a zone's apex".
2195  */
2196
2197 static isc_result_t
2198 remove_orphaned_ds(dns_db_t *db, dns_dbversion_t *newver, dns_diff_t *diff) {
2199         isc_result_t result;
2200         isc_boolean_t ns_exists, ds_exists;
2201         dns_difftuple_t *t;
2202
2203         for (t = ISC_LIST_HEAD(diff->tuples);
2204              t != NULL;
2205              t = ISC_LIST_NEXT(t, link)) {
2206                 if (t->op != DNS_DIFFOP_ADD ||
2207                     t->rdata.type != dns_rdatatype_ns)
2208                         continue;
2209                 CHECK(rrset_exists(db, newver, &t->name, dns_rdatatype_ns, 0,
2210                                    &ns_exists));
2211                 if (ns_exists)
2212                         continue;
2213                 CHECK(rrset_exists(db, newver, &t->name, dns_rdatatype_ds, 0,
2214                                    &ds_exists));
2215                 if (!ds_exists)
2216                         continue;
2217                 CHECK(delete_if(true_p, db, newver, &t->name,
2218                                 dns_rdatatype_ds, 0, NULL, diff));
2219         }
2220         return (ISC_R_SUCCESS);
2221
2222  failure:
2223         return (result);
2224 }
2225
2226 /*
2227  * This implements the post load integrity checks for mx records.
2228  */
2229 static isc_result_t
2230 check_mx(ns_client_t *client, dns_zone_t *zone,
2231          dns_db_t *db, dns_dbversion_t *newver, dns_diff_t *diff)
2232 {
2233         char tmp[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:123.123.123.123.")];
2234         char ownerbuf[DNS_NAME_FORMATSIZE];
2235         char namebuf[DNS_NAME_FORMATSIZE];
2236         char altbuf[DNS_NAME_FORMATSIZE];
2237         dns_difftuple_t *t;
2238         dns_fixedname_t fixed;
2239         dns_name_t *foundname;
2240         dns_rdata_mx_t mx;
2241         dns_rdata_t rdata;
2242         isc_boolean_t ok = ISC_TRUE;
2243         isc_boolean_t isaddress;
2244         isc_result_t result;
2245         struct in6_addr addr6;
2246         struct in_addr addr;
2247         unsigned int options;
2248
2249         dns_fixedname_init(&fixed);
2250         foundname = dns_fixedname_name(&fixed);
2251         dns_rdata_init(&rdata);
2252         options = dns_zone_getoptions(zone);
2253
2254         for (t = ISC_LIST_HEAD(diff->tuples);
2255              t != NULL;
2256              t = ISC_LIST_NEXT(t, link)) {
2257                 if (t->op != DNS_DIFFOP_ADD ||
2258                     t->rdata.type != dns_rdatatype_mx)
2259                         continue;
2260
2261                 result = dns_rdata_tostruct(&t->rdata, &mx, NULL);
2262                 RUNTIME_CHECK(result == ISC_R_SUCCESS);
2263                 /*
2264                  * Check if we will error out if we attempt to reload the
2265                  * zone.
2266                  */
2267                 dns_name_format(&mx.mx, namebuf, sizeof(namebuf));
2268                 dns_name_format(&t->name, ownerbuf, sizeof(ownerbuf));
2269                 isaddress = ISC_FALSE;
2270                 if ((options & DNS_RDATA_CHECKMX) != 0 &&
2271                     strlcpy(tmp, namebuf, sizeof(tmp)) < sizeof(tmp)) {
2272                         if (tmp[strlen(tmp) - 1] == '.')
2273                                 tmp[strlen(tmp) - 1] = '\0';
2274                         if (inet_aton(tmp, &addr) == 1 ||
2275                             inet_pton(AF_INET6, tmp, &addr6) == 1)
2276                                 isaddress = ISC_TRUE;
2277                 }
2278
2279                 if (isaddress && (options & DNS_RDATA_CHECKMXFAIL) != 0) {
2280                         update_log(client, zone, ISC_LOG_ERROR,
2281                                    "%s/MX: '%s': %s",
2282                                    ownerbuf, namebuf,
2283                                    dns_result_totext(DNS_R_MXISADDRESS));
2284                         ok = ISC_FALSE;
2285                 } else if (isaddress) {
2286                         update_log(client, zone, ISC_LOG_WARNING,
2287                                    "%s/MX: warning: '%s': %s",
2288                                    ownerbuf, namebuf,
2289                                    dns_result_totext(DNS_R_MXISADDRESS));
2290                 }
2291
2292                 /*
2293                  * Check zone integrity checks.
2294                  */
2295                 if ((options & DNS_ZONEOPT_CHECKINTEGRITY) == 0)
2296                         continue;
2297                 result = dns_db_find(db, &mx.mx, newver, dns_rdatatype_a,
2298                                      0, 0, NULL, foundname, NULL, NULL);
2299                 if (result == ISC_R_SUCCESS)
2300                         continue;
2301
2302                 if (result == DNS_R_NXRRSET) {
2303                         result = dns_db_find(db, &mx.mx, newver,
2304                                              dns_rdatatype_aaaa,
2305                                              0, 0, NULL, foundname,
2306                                              NULL, NULL);
2307                         if (result == ISC_R_SUCCESS)
2308                                 continue;
2309                 }
2310
2311                 if (result == DNS_R_NXRRSET || result == DNS_R_NXDOMAIN) {
2312                         update_log(client, zone, ISC_LOG_ERROR,
2313                                    "%s/MX '%s' has no address records "
2314                                    "(A or AAAA)", ownerbuf, namebuf);
2315                         ok = ISC_FALSE;
2316                 } else if (result == DNS_R_CNAME) {
2317                         update_log(client, zone, ISC_LOG_ERROR,
2318                                    "%s/MX '%s' is a CNAME (illegal)",
2319                                    ownerbuf, namebuf);
2320                         ok = ISC_FALSE;
2321                 } else if (result == DNS_R_DNAME) {
2322                         dns_name_format(foundname, altbuf, sizeof altbuf);
2323                         update_log(client, zone, ISC_LOG_ERROR,
2324                                    "%s/MX '%s' is below a DNAME '%s' (illegal)",
2325                                    ownerbuf, namebuf, altbuf);
2326                         ok = ISC_FALSE;
2327                 }
2328         }
2329         return (ok ? ISC_R_SUCCESS : DNS_R_REFUSED);
2330 }
2331
2332 static void
2333 update_action(isc_task_t *task, isc_event_t *event) {
2334         update_event_t *uev = (update_event_t *) event;
2335         dns_zone_t *zone = uev->zone;
2336         ns_client_t *client = (ns_client_t *)event->ev_arg;
2337
2338         isc_result_t result;
2339         dns_db_t *db = NULL;
2340         dns_dbversion_t *oldver = NULL;
2341         dns_dbversion_t *ver = NULL;
2342         dns_diff_t diff;        /* Pending updates. */
2343         dns_diff_t temp;        /* Pending RR existence assertions. */
2344         isc_boolean_t soa_serial_changed = ISC_FALSE;
2345         isc_mem_t *mctx = client->mctx;
2346         dns_rdatatype_t covers;
2347         dns_message_t *request = client->message;
2348         dns_rdataclass_t zoneclass;
2349         dns_name_t *zonename;
2350         dns_ssutable_t *ssutable = NULL;
2351         dns_fixedname_t tmpnamefixed;
2352         dns_name_t *tmpname = NULL;
2353         unsigned int options;
2354
2355         INSIST(event->ev_type == DNS_EVENT_UPDATE);
2356
2357         dns_diff_init(mctx, &diff);
2358         dns_diff_init(mctx, &temp);
2359
2360         CHECK(dns_zone_getdb(zone, &db));
2361         zonename = dns_db_origin(db);
2362         zoneclass = dns_db_class(db);
2363         dns_zone_getssutable(zone, &ssutable);
2364         dns_db_currentversion(db, &oldver);
2365         CHECK(dns_db_newversion(db, &ver));
2366
2367         /*
2368          * Check prerequisites.
2369          */
2370
2371         for (result = dns_message_firstname(request, DNS_SECTION_PREREQUISITE);
2372              result == ISC_R_SUCCESS;
2373              result = dns_message_nextname(request, DNS_SECTION_PREREQUISITE))
2374         {
2375                 dns_name_t *name = NULL;
2376                 dns_rdata_t rdata = DNS_RDATA_INIT;
2377                 dns_ttl_t ttl;
2378                 dns_rdataclass_t update_class;
2379                 isc_boolean_t flag;
2380
2381                 get_current_rr(request, DNS_SECTION_PREREQUISITE, zoneclass,
2382                                &name, &rdata, &covers, &ttl, &update_class);
2383
2384                 if (ttl != 0)
2385                         FAILC(DNS_R_FORMERR, "prerequisite TTL is not zero");
2386
2387                 if (! dns_name_issubdomain(name, zonename))
2388                         FAILN(DNS_R_NOTZONE, name,
2389                                 "prerequisite name is out of zone");
2390
2391                 if (update_class == dns_rdataclass_any) {
2392                         if (rdata.length != 0)
2393                                 FAILC(DNS_R_FORMERR,
2394                                       "class ANY prerequisite "
2395                                       "RDATA is not empty");
2396                         if (rdata.type == dns_rdatatype_any) {
2397                                 CHECK(name_exists(db, ver, name, &flag));
2398                                 if (! flag) {
2399                                         FAILN(DNS_R_NXDOMAIN, name,
2400                                               "'name in use' prerequisite "
2401                                               "not satisfied");
2402                                 }
2403                         } else {
2404                                 CHECK(rrset_exists(db, ver, name,
2405                                                    rdata.type, covers, &flag));
2406                                 if (! flag) {
2407                                         /* RRset does not exist. */
2408                                         FAILNT(DNS_R_NXRRSET, name, rdata.type,
2409                                         "'rrset exists (value independent)' "
2410                                         "prerequisite not satisfied");
2411                                 }
2412                         }
2413                 } else if (update_class == dns_rdataclass_none) {
2414                         if (rdata.length != 0)
2415                                 FAILC(DNS_R_FORMERR,
2416                                       "class NONE prerequisite "
2417                                       "RDATA is not empty");
2418                         if (rdata.type == dns_rdatatype_any) {
2419                                 CHECK(name_exists(db, ver, name, &flag));
2420                                 if (flag) {
2421                                         FAILN(DNS_R_YXDOMAIN, name,
2422                                               "'name not in use' prerequisite "
2423                                               "not satisfied");
2424                                 }
2425                         } else {
2426                                 CHECK(rrset_exists(db, ver, name,
2427                                                    rdata.type, covers, &flag));
2428                                 if (flag) {
2429                                         /* RRset exists. */
2430                                         FAILNT(DNS_R_YXRRSET, name, rdata.type,
2431                                                "'rrset does not exist' "
2432                                                "prerequisite not satisfied");
2433                                 }
2434                         }
2435                 } else if (update_class == zoneclass) {
2436                         /* "temp<rr.name, rr.type> += rr;" */
2437                         result = temp_append(&temp, name, &rdata);
2438                         if (result != ISC_R_SUCCESS) {
2439                                 UNEXPECTED_ERROR(__FILE__, __LINE__,
2440                                          "temp entry creation failed: %s",
2441                                                  dns_result_totext(result));
2442                                 FAIL(ISC_R_UNEXPECTED);
2443                         }
2444                 } else {
2445                         FAILC(DNS_R_FORMERR, "malformed prerequisite");
2446                 }
2447         }
2448         if (result != ISC_R_NOMORE)
2449                 FAIL(result);
2450
2451
2452         /*
2453          * Perform the final check of the "rrset exists (value dependent)"
2454          * prerequisites.
2455          */
2456         if (ISC_LIST_HEAD(temp.tuples) != NULL) {
2457                 dns_rdatatype_t type;
2458
2459                 /*
2460                  * Sort the prerequisite records by owner name,
2461                  * type, and rdata.
2462                  */
2463                 result = dns_diff_sort(&temp, temp_order);
2464                 if (result != ISC_R_SUCCESS)
2465                         FAILC(result, "'RRset exists (value dependent)' "
2466                               "prerequisite not satisfied");
2467
2468                 dns_fixedname_init(&tmpnamefixed);
2469                 tmpname = dns_fixedname_name(&tmpnamefixed);
2470                 result = temp_check(mctx, &temp, db, ver, tmpname, &type);
2471                 if (result != ISC_R_SUCCESS)
2472                         FAILNT(result, tmpname, type,
2473                                "'RRset exists (value dependent)' "
2474                                "prerequisite not satisfied");
2475         }
2476
2477         update_log(client, zone, LOGLEVEL_DEBUG,
2478                    "prerequisites are OK");
2479
2480         /*
2481          * Check Requestor's Permissions.  It seems a bit silly to do this
2482          * only after prerequisite testing, but that is what RFC2136 says.
2483          */
2484         result = ISC_R_SUCCESS;
2485         if (ssutable == NULL)
2486                 CHECK(checkupdateacl(client, dns_zone_getupdateacl(zone),
2487                                      "update", zonename, ISC_FALSE));
2488         else if (client->signer == NULL)
2489                 CHECK(checkupdateacl(client, NULL, "update", zonename,
2490                                      ISC_FALSE));
2491
2492         if (dns_zone_getupdatedisabled(zone))
2493                 FAILC(DNS_R_REFUSED, "dynamic update temporarily disabled");
2494
2495         /*
2496          * Perform the Update Section Prescan.
2497          */
2498
2499         for (result = dns_message_firstname(request, DNS_SECTION_UPDATE);
2500              result == ISC_R_SUCCESS;
2501              result = dns_message_nextname(request, DNS_SECTION_UPDATE))
2502         {
2503                 dns_name_t *name = NULL;
2504                 dns_rdata_t rdata = DNS_RDATA_INIT;
2505                 dns_ttl_t ttl;
2506                 dns_rdataclass_t update_class;
2507                 get_current_rr(request, DNS_SECTION_UPDATE, zoneclass,
2508                                &name, &rdata, &covers, &ttl, &update_class);
2509
2510                 if (! dns_name_issubdomain(name, zonename))
2511                         FAILC(DNS_R_NOTZONE,
2512                               "update RR is outside zone");
2513                 if (update_class == zoneclass) {
2514                         /*
2515                          * Check for meta-RRs.  The RFC2136 pseudocode says
2516                          * check for ANY|AXFR|MAILA|MAILB, but the text adds
2517                          * "or any other QUERY metatype"
2518                          */
2519                         if (dns_rdatatype_ismeta(rdata.type)) {
2520                                 FAILC(DNS_R_FORMERR,
2521                                       "meta-RR in update");
2522                         }
2523                         result = dns_zone_checknames(zone, name, &rdata);
2524                         if (result != ISC_R_SUCCESS)
2525                                 FAIL(DNS_R_REFUSED);
2526                 } else if (update_class == dns_rdataclass_any) {
2527                         if (ttl != 0 || rdata.length != 0 ||
2528                             (dns_rdatatype_ismeta(rdata.type) &&
2529                              rdata.type != dns_rdatatype_any))
2530                                 FAILC(DNS_R_FORMERR,
2531                                       "meta-RR in update");
2532                 } else if (update_class == dns_rdataclass_none) {
2533                         if (ttl != 0 ||
2534                             dns_rdatatype_ismeta(rdata.type))
2535                                 FAILC(DNS_R_FORMERR,
2536                                       "meta-RR in update");
2537                 } else {
2538                         update_log(client, zone, ISC_LOG_WARNING,
2539                                    "update RR has incorrect class %d",
2540                                    update_class);
2541                         FAIL(DNS_R_FORMERR);
2542                 }
2543                 /*
2544                  * draft-ietf-dnsind-simple-secure-update-01 says
2545                  * "Unlike traditional dynamic update, the client
2546                  * is forbidden from updating NSEC records."
2547                  */
2548                 if (dns_db_issecure(db)) {
2549                         if (rdata.type == dns_rdatatype_nsec) {
2550                                 FAILC(DNS_R_REFUSED,
2551                                       "explicit NSEC updates are not allowed "
2552                                       "in secure zones");
2553                         }
2554                         else if (rdata.type == dns_rdatatype_rrsig) {
2555                                 FAILC(DNS_R_REFUSED,
2556                                       "explicit RRSIG updates are currently not "
2557                                       "supported in secure zones");
2558                         }
2559                 }
2560
2561                 if (ssutable != NULL && client->signer != NULL) {
2562                         if (rdata.type != dns_rdatatype_any) {
2563                                 if (!dns_ssutable_checkrules(ssutable,
2564                                                              client->signer,
2565                                                              name, rdata.type))
2566                                         FAILC(DNS_R_REFUSED,
2567                                               "rejected by secure update");
2568                         }
2569                         else {
2570                                 if (!ssu_checkall(db, ver, name, ssutable,
2571                                                   client->signer))
2572                                         FAILC(DNS_R_REFUSED,
2573                                               "rejected by secure update");
2574                         }
2575                 }
2576         }
2577         if (result != ISC_R_NOMORE)
2578                 FAIL(result);
2579
2580         update_log(client, zone, LOGLEVEL_DEBUG,
2581                    "update section prescan OK");
2582
2583         /*
2584          * Process the Update Section.
2585          */
2586
2587         options = dns_zone_getoptions(zone);
2588         for (result = dns_message_firstname(request, DNS_SECTION_UPDATE);
2589              result == ISC_R_SUCCESS;
2590              result = dns_message_nextname(request, DNS_SECTION_UPDATE))
2591         {
2592                 dns_name_t *name = NULL;
2593                 dns_rdata_t rdata = DNS_RDATA_INIT;
2594                 dns_ttl_t ttl;
2595                 dns_rdataclass_t update_class;
2596                 isc_boolean_t flag;
2597
2598                 get_current_rr(request, DNS_SECTION_UPDATE, zoneclass,
2599                                &name, &rdata, &covers, &ttl, &update_class);
2600
2601                 if (update_class == zoneclass) {
2602
2603                         /*
2604                          * RFC1123 doesn't allow MF and MD in master zones.                              */
2605                         if (rdata.type == dns_rdatatype_md ||
2606                             rdata.type == dns_rdatatype_mf) {
2607                                 char typebuf[DNS_RDATATYPE_FORMATSIZE];
2608
2609                                 dns_rdatatype_format(rdata.type, typebuf,
2610                                                      sizeof(typebuf));
2611                                 update_log(client, zone, LOGLEVEL_PROTOCOL,
2612                                            "attempt to add %s ignored",
2613                                            typebuf);
2614                                 continue;
2615                         }
2616                         if (rdata.type == dns_rdatatype_ns &&
2617                             dns_name_iswildcard(name)) {
2618                                 update_log(client, zone,
2619                                            LOGLEVEL_PROTOCOL,
2620                                            "attempt to add wildcard NS record"
2621                                            "ignored");
2622                                 continue;
2623                         }
2624                         if (rdata.type == dns_rdatatype_cname) {
2625                                 CHECK(cname_incompatible_rrset_exists(db, ver,
2626                                                                       name,
2627                                                                       &flag));
2628                                 if (flag) {
2629                                         update_log(client, zone,
2630                                                    LOGLEVEL_PROTOCOL,
2631                                                    "attempt to add CNAME "
2632                                                    "alongside non-CNAME "
2633                                                    "ignored");
2634                                         continue;
2635                                 }
2636                         } else {
2637                                 CHECK(rrset_exists(db, ver, name,
2638                                                    dns_rdatatype_cname, 0,
2639                                                    &flag));
2640                                 if (flag &&
2641                                     ! dns_rdatatype_isdnssec(rdata.type))
2642                                 {
2643                                         update_log(client, zone,
2644                                                    LOGLEVEL_PROTOCOL,
2645                                                    "attempt to add non-CNAME "
2646                                                    "alongside CNAME ignored");
2647                                         continue;
2648                                 }
2649                         }
2650                         if (rdata.type == dns_rdatatype_soa) {
2651                                 isc_boolean_t ok;
2652                                 CHECK(rrset_exists(db, ver, name,
2653                                                    dns_rdatatype_soa, 0,
2654                                                    &flag));
2655                                 if (! flag) {
2656                                         update_log(client, zone,
2657                                                    LOGLEVEL_PROTOCOL,
2658                                                    "attempt to create 2nd "
2659                                                    "SOA ignored");
2660                                         continue;
2661                                 }
2662                                 CHECK(check_soa_increment(db, ver, &rdata,
2663                                                           &ok));
2664                                 if (! ok) {
2665                                         update_log(client, zone,
2666                                                    LOGLEVEL_PROTOCOL,
2667                                                    "SOA update failed to "
2668                                                    "increment serial, "
2669                                                    "ignoring it");
2670                                         continue;
2671                                 }
2672                                 soa_serial_changed = ISC_TRUE;
2673                         }
2674                         if ((options & DNS_ZONEOPT_CHECKWILDCARD) != 0 &&
2675                             dns_name_internalwildcard(name)) {
2676                                 char namestr[DNS_NAME_FORMATSIZE];
2677                                 dns_name_format(name, namestr,
2678                                                 sizeof(namestr));
2679                                 update_log(client, zone, LOGLEVEL_PROTOCOL,
2680                                            "warning: ownername '%s' contains "
2681                                            "a non-terminal wildcard", namestr);
2682                         }
2683
2684                         if (isc_log_wouldlog(ns_g_lctx, LOGLEVEL_PROTOCOL)) {
2685                                 char namestr[DNS_NAME_FORMATSIZE];
2686                                 char typestr[DNS_RDATATYPE_FORMATSIZE];
2687                                 dns_name_format(name, namestr,
2688                                                 sizeof(namestr));
2689                                 dns_rdatatype_format(rdata.type, typestr,
2690                                                      sizeof(typestr));
2691                                 update_log(client, zone,
2692                                            LOGLEVEL_PROTOCOL,
2693                                            "adding an RR at '%s' %s",
2694                                            namestr, typestr);
2695                         }
2696
2697                         /* Prepare the affected RRset for the addition. */
2698                         {
2699                                 add_rr_prepare_ctx_t ctx;
2700                                 ctx.db = db;
2701                                 ctx.ver = ver;
2702                                 ctx.diff = &diff;
2703                                 ctx.name = name;
2704                                 ctx.update_rr = &rdata;
2705                                 ctx.update_rr_ttl = ttl;
2706                                 ctx.ignore_add = ISC_FALSE;
2707                                 dns_diff_init(mctx, &ctx.del_diff);
2708                                 dns_diff_init(mctx, &ctx.add_diff);
2709                                 CHECK(foreach_rr(db, ver, name, rdata.type,
2710                                                  covers, add_rr_prepare_action,
2711                                                  &ctx));
2712
2713                                 if (ctx.ignore_add) {
2714                                         dns_diff_clear(&ctx.del_diff);
2715                                         dns_diff_clear(&ctx.add_diff);
2716                                 } else {
2717                                         CHECK(do_diff(&ctx.del_diff, db, ver, &diff));
2718                                         CHECK(do_diff(&ctx.add_diff, db, ver, &diff));
2719                                         CHECK(update_one_rr(db, ver, &diff,
2720                                                             DNS_DIFFOP_ADD,
2721                                                             name, ttl, &rdata));
2722                                 }
2723                         }
2724                 } else if (update_class == dns_rdataclass_any) {
2725                         if (rdata.type == dns_rdatatype_any) {
2726                                 if (isc_log_wouldlog(ns_g_lctx,
2727                                                      LOGLEVEL_PROTOCOL))
2728                                 {
2729                                         char namestr[DNS_NAME_FORMATSIZE];
2730                                         dns_name_format(name, namestr,
2731                                                         sizeof(namestr));
2732                                         update_log(client, zone,
2733                                                    LOGLEVEL_PROTOCOL,
2734                                                    "delete all rrsets from "
2735                                                    "name '%s'", namestr);
2736                                 }
2737                                 if (dns_name_equal(name, zonename)) {
2738                                         CHECK(delete_if(type_not_soa_nor_ns_p,
2739                                                         db, ver, name,
2740                                                         dns_rdatatype_any, 0,
2741                                                         &rdata, &diff));
2742                                 } else {
2743                                         CHECK(delete_if(type_not_dnssec,
2744                                                         db, ver, name,
2745                                                         dns_rdatatype_any, 0,
2746                                                         &rdata, &diff));
2747                                 }
2748                         } else if (dns_name_equal(name, zonename) &&
2749                                    (rdata.type == dns_rdatatype_soa ||
2750                                     rdata.type == dns_rdatatype_ns)) {
2751                                 update_log(client, zone,
2752                                            LOGLEVEL_PROTOCOL,
2753                                            "attempt to delete all SOA "
2754                                            "or NS records ignored");
2755                                 continue;
2756                         } else {
2757                                 if (isc_log_wouldlog(ns_g_lctx,
2758                                                      LOGLEVEL_PROTOCOL))
2759                                 {
2760                                         char namestr[DNS_NAME_FORMATSIZE];
2761                                         char typestr[DNS_RDATATYPE_FORMATSIZE];
2762                                         dns_name_format(name, namestr,
2763                                                         sizeof(namestr));
2764                                         dns_rdatatype_format(rdata.type,
2765                                                              typestr,
2766                                                              sizeof(typestr));
2767                                         update_log(client, zone,
2768                                                    LOGLEVEL_PROTOCOL,
2769                                                    "deleting rrset at '%s' %s",
2770                                                    namestr, typestr);
2771                                 }
2772                                 CHECK(delete_if(true_p, db, ver, name,
2773                                                 rdata.type, covers, &rdata,
2774                                                 &diff));
2775                         }
2776                 } else if (update_class == dns_rdataclass_none) {
2777                         /*
2778                          * The (name == zonename) condition appears in
2779                          * RFC2136 3.4.2.4 but is missing from the pseudocode.
2780                          */
2781                         if (dns_name_equal(name, zonename)) {
2782                                 if (rdata.type == dns_rdatatype_soa) {
2783                                         update_log(client, zone,
2784                                                    LOGLEVEL_PROTOCOL,
2785                                                    "attempt to delete SOA "
2786                                                    "ignored");
2787                                         continue;
2788                                 }
2789                                 if (rdata.type == dns_rdatatype_ns) {
2790                                         int count;
2791                                         CHECK(rr_count(db, ver, name,
2792                                                        dns_rdatatype_ns,
2793                                                        0, &count));
2794                                         if (count == 1) {
2795                                                 update_log(client, zone,
2796                                                            LOGLEVEL_PROTOCOL,
2797                                                            "attempt to "
2798                                                            "delete last "
2799                                                            "NS ignored");
2800                                                 continue;
2801                                         }
2802                                 }
2803                         }
2804                         update_log(client, zone,
2805                                    LOGLEVEL_PROTOCOL,
2806                                    "deleting an RR");
2807                         CHECK(delete_if(rr_equal_p, db, ver, name,
2808                                         rdata.type, covers, &rdata, &diff));
2809                 }
2810         }
2811         if (result != ISC_R_NOMORE)
2812                 FAIL(result);
2813
2814         /*
2815          * If any changes were made, increment the SOA serial number,
2816          * update RRSIGs and NSECs (if zone is secure), and write the update
2817          * to the journal.
2818          */
2819         if (! ISC_LIST_EMPTY(diff.tuples)) {
2820                 char *journalfile;
2821                 dns_journal_t *journal;
2822
2823                 /*
2824                  * Increment the SOA serial, but only if it was not
2825                  * changed as a result of an update operation.
2826                  */
2827                 if (! soa_serial_changed) {
2828                         CHECK(increment_soa_serial(db, ver, &diff, mctx));
2829                 }
2830
2831                 CHECK(check_mx(client, zone, db, ver, &diff));
2832
2833                 CHECK(remove_orphaned_ds(db, ver, &diff));
2834
2835                 if (dns_db_issecure(db)) {
2836                         result = update_signatures(client, zone, db, oldver,
2837                                                    ver, &diff,
2838                                          dns_zone_getsigvalidityinterval(zone));
2839                         if (result != ISC_R_SUCCESS) {
2840                                 update_log(client, zone,
2841                                            ISC_LOG_ERROR,
2842                                            "RRSIG/NSEC update failed: %s",
2843                                            isc_result_totext(result));
2844                                 goto failure;
2845                         }
2846                 }
2847
2848                 journalfile = dns_zone_getjournal(zone);
2849                 if (journalfile != NULL) {
2850                         update_log(client, zone, LOGLEVEL_DEBUG,
2851                                    "writing journal %s", journalfile);
2852
2853                         journal = NULL;
2854                         result = dns_journal_open(mctx, journalfile,
2855                                                   ISC_TRUE, &journal);
2856                         if (result != ISC_R_SUCCESS)
2857                                 FAILS(result, "journal open failed");
2858
2859                         result = dns_journal_write_transaction(journal, &diff);
2860                         if (result != ISC_R_SUCCESS) {
2861                                 dns_journal_destroy(&journal);
2862                                 FAILS(result, "journal write failed");
2863                         }
2864
2865                         dns_journal_destroy(&journal);
2866                 }
2867
2868                 /*
2869                  * XXXRTH  Just a note that this committing code will have
2870                  *         to change to handle databases that need two-phase
2871                  *         commit, but this isn't a priority.
2872                  */
2873                 update_log(client, zone, LOGLEVEL_DEBUG,
2874                            "committing update transaction");
2875                 dns_db_closeversion(db, &ver, ISC_TRUE);
2876
2877                 /*
2878                  * Mark the zone as dirty so that it will be written to disk.
2879                  */
2880                 dns_zone_markdirty(zone);
2881
2882                 /*
2883                  * Notify slaves of the change we just made.
2884                  */
2885                 dns_zone_notify(zone);
2886         } else {
2887                 update_log(client, zone, LOGLEVEL_DEBUG, "redundant request");
2888                 dns_db_closeversion(db, &ver, ISC_TRUE);
2889         }
2890         result = ISC_R_SUCCESS;
2891         goto common;
2892
2893  failure:
2894         /*
2895          * The reason for failure should have been logged at this point.
2896          */
2897         if (ver != NULL) {
2898                 update_log(client, zone, LOGLEVEL_DEBUG,
2899                            "rolling back");
2900                 dns_db_closeversion(db, &ver, ISC_FALSE);
2901         }
2902
2903  common:
2904         dns_diff_clear(&temp);
2905         dns_diff_clear(&diff);
2906
2907         if (oldver != NULL)
2908                 dns_db_closeversion(db, &oldver, ISC_FALSE);
2909
2910         if (db != NULL)
2911                 dns_db_detach(&db);
2912
2913         if (ssutable != NULL)
2914                 dns_ssutable_detach(&ssutable);
2915
2916         if (zone != NULL)
2917                 dns_zone_detach(&zone);
2918
2919         isc_task_detach(&task);
2920         uev->result = result;
2921         uev->ev_type = DNS_EVENT_UPDATEDONE;
2922         uev->ev_action = updatedone_action;
2923         isc_task_send(client->task, &event);
2924         INSIST(event == NULL);
2925 }
2926
2927 static void
2928 updatedone_action(isc_task_t *task, isc_event_t *event) {
2929         update_event_t *uev = (update_event_t *) event;
2930         ns_client_t *client = (ns_client_t *) event->ev_arg;
2931
2932         UNUSED(task);
2933
2934         INSIST(event->ev_type == DNS_EVENT_UPDATEDONE);
2935         INSIST(task == client->task);
2936
2937         INSIST(client->nupdates > 0);
2938         client->nupdates--;
2939         respond(client, uev->result);
2940         isc_event_free(&event);
2941         ns_client_detach(&client);
2942 }
2943
2944 /*%
2945  * Update forwarding support.
2946  */
2947
2948 static void
2949 forward_fail(isc_task_t *task, isc_event_t *event) {
2950         ns_client_t *client = (ns_client_t *)event->ev_arg;
2951
2952         UNUSED(task);
2953
2954         INSIST(client->nupdates > 0);
2955         client->nupdates--;
2956         respond(client, DNS_R_SERVFAIL);
2957         isc_event_free(&event);
2958         ns_client_detach(&client);
2959 }
2960
2961
2962 static void
2963 forward_callback(void *arg, isc_result_t result, dns_message_t *answer) {
2964         update_event_t *uev = arg;
2965         ns_client_t *client = uev->ev_arg;
2966
2967         if (result != ISC_R_SUCCESS) {
2968                 INSIST(answer == NULL);
2969                 uev->ev_type = DNS_EVENT_UPDATEDONE;
2970                 uev->ev_action = forward_fail;
2971         } else {
2972                 uev->ev_type = DNS_EVENT_UPDATEDONE;
2973                 uev->ev_action = forward_done;
2974                 uev->answer = answer;
2975         }
2976         isc_task_send(client->task, ISC_EVENT_PTR(&uev));
2977 }
2978
2979 static void
2980 forward_done(isc_task_t *task, isc_event_t *event) {
2981         update_event_t *uev = (update_event_t *) event;
2982         ns_client_t *client = (ns_client_t *)event->ev_arg;
2983
2984         UNUSED(task);
2985
2986         INSIST(client->nupdates > 0);
2987         client->nupdates--;
2988         ns_client_sendraw(client, uev->answer);
2989         dns_message_destroy(&uev->answer);
2990         isc_event_free(&event);
2991         ns_client_detach(&client);
2992 }
2993
2994 static void
2995 forward_action(isc_task_t *task, isc_event_t *event) {
2996         update_event_t *uev = (update_event_t *) event;
2997         dns_zone_t *zone = uev->zone;
2998         ns_client_t *client = (ns_client_t *)event->ev_arg;
2999         isc_result_t result;
3000
3001         result = dns_zone_forwardupdate(zone, client->message,
3002                                         forward_callback, event);
3003         if (result != ISC_R_SUCCESS) {
3004                 uev->ev_type = DNS_EVENT_UPDATEDONE;
3005                 uev->ev_action = forward_fail;
3006                 isc_task_send(client->task, &event);
3007         }
3008         dns_zone_detach(&zone);
3009         isc_task_detach(&task);
3010 }
3011
3012 static isc_result_t
3013 send_forward_event(ns_client_t *client, dns_zone_t *zone) {
3014         isc_result_t result = ISC_R_SUCCESS;
3015         update_event_t *event = NULL;
3016         isc_task_t *zonetask = NULL;
3017         ns_client_t *evclient;
3018
3019         event = (update_event_t *)
3020                 isc_event_allocate(client->mctx, client, DNS_EVENT_UPDATE,
3021                                    forward_action, NULL, sizeof(*event));
3022         if (event == NULL)
3023                 FAIL(ISC_R_NOMEMORY);
3024         event->zone = zone;
3025         event->result = ISC_R_SUCCESS;
3026
3027         evclient = NULL;
3028         ns_client_attach(client, &evclient);
3029         INSIST(client->nupdates == 0);
3030         client->nupdates++;
3031         event->ev_arg = evclient;
3032
3033         dns_zone_gettask(zone, &zonetask);
3034         isc_task_send(zonetask, ISC_EVENT_PTR(&event));
3035
3036  failure:
3037         if (event != NULL)
3038                 isc_event_free(ISC_EVENT_PTR(&event));
3039         return (result);
3040 }