contrib/bind9/lib/dns/xfrin.c

   1 /*
   2  * Copyright (C) 2004-2008, 2011-2013  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 /* $Id$ */
  19
  20 /*! \file */
  21
  22 #include <config.h>
  23
  24 #include <isc/mem.h>
  25 #include <isc/print.h>
  26 #include <isc/random.h>
  27 #include <isc/string.h>         /* Required for HP/UX (and others?) */
  28 #include <isc/task.h>
  29 #include <isc/timer.h>
  30 #include <isc/util.h>
  31
  32 #include <dns/db.h>
  33 #include <dns/diff.h>
  34 #include <dns/events.h>
  35 #include <dns/journal.h>
  36 #include <dns/log.h>
  37 #include <dns/message.h>
  38 #include <dns/rdataclass.h>
  39 #include <dns/rdatalist.h>
  40 #include <dns/rdataset.h>
  41 #include <dns/result.h>
  42 #include <dns/soa.h>
  43 #include <dns/tcpmsg.h>
  44 #include <dns/timer.h>
  45 #include <dns/tsig.h>
  46 #include <dns/view.h>
  47 #include <dns/xfrin.h>
  48 #include <dns/zone.h>
  49
  50 #include <dst/dst.h>
  51
  52 /*
  53  * Incoming AXFR and IXFR.
  54  */
  55
  56 /*%
  57  * It would be non-sensical (or at least obtuse) to use FAIL() with an
  58  * ISC_R_SUCCESS code, but the test is there to keep the Solaris compiler
  59  * from complaining about "end-of-loop code not reached".
  60  */
  61 #define FAIL(code) \
  62         do { result = (code);                                   \
  63                 if (result != ISC_R_SUCCESS) goto failure;      \
  64         } while (0)
  65
  66 #define CHECK(op) \
  67         do { result = (op);                                     \
  68                 if (result != ISC_R_SUCCESS) goto failure;      \
  69         } while (0)
  70
  71 /*%
  72  * The states of the *XFR state machine.  We handle both IXFR and AXFR
  73  * with a single integrated state machine because they cannot be distinguished
  74  * immediately - an AXFR response to an IXFR request can only be detected
  75  * when the first two (2) response RRs have already been received.
  76  */
  77 typedef enum {
  78         XFRST_SOAQUERY,
  79         XFRST_GOTSOA,
  80         XFRST_INITIALSOA,
  81         XFRST_FIRSTDATA,
  82         XFRST_IXFR_DELSOA,
  83         XFRST_IXFR_DEL,
  84         XFRST_IXFR_ADDSOA,
  85         XFRST_IXFR_ADD,
  86         XFRST_IXFR_END,
  87         XFRST_AXFR,
  88         XFRST_AXFR_END
  89 } xfrin_state_t;
  90
  91 /*%
  92  * Incoming zone transfer context.
  93  */
  94
  95 struct dns_xfrin_ctx {
  96         unsigned int            magic;
  97         isc_mem_t               *mctx;
  98         dns_zone_t              *zone;
  99
 100         int                     refcount;
 101
 102         isc_task_t              *task;
 103         isc_timer_t             *timer;
 104         isc_socketmgr_t         *socketmgr;
 105
 106         int                     connects;       /*%< Connect in progress */
 107         int                     sends;          /*%< Send in progress */
 108         int                     recvs;          /*%< Receive in progress */
 109         isc_boolean_t           shuttingdown;
 110
 111         dns_name_t              name;           /*%< Name of zone to transfer */
 112         dns_rdataclass_t        rdclass;
 113
 114         isc_boolean_t           checkid;
 115         dns_messageid_t         id;
 116
 117         /*%
 118          * Requested transfer type (dns_rdatatype_axfr or
 119          * dns_rdatatype_ixfr).  The actual transfer type
 120          * may differ due to IXFR->AXFR fallback.
 121          */
 122         dns_rdatatype_t         reqtype;
 123
 124         isc_sockaddr_t          masteraddr;
 125         isc_sockaddr_t          sourceaddr;
 126         isc_socket_t            *socket;
 127
 128         /*% Buffer for IXFR/AXFR request message */
 129         isc_buffer_t            qbuffer;
 130         unsigned char           qbuffer_data[512];
 131
 132         /*% Incoming reply TCP message */
 133         dns_tcpmsg_t            tcpmsg;
 134         isc_boolean_t           tcpmsg_valid;
 135
 136         dns_db_t                *db;
 137         dns_dbversion_t         *ver;
 138         dns_diff_t              diff;           /*%< Pending database changes */
 139         int                     difflen;        /*%< Number of pending tuples */
 140
 141         xfrin_state_t           state;
 142         isc_uint32_t            end_serial;
 143         isc_boolean_t           is_ixfr;
 144
 145         unsigned int            nmsg;           /*%< Number of messages recvd */
 146         unsigned int            nrecs;          /*%< Number of records recvd */
 147         isc_uint64_t            nbytes;         /*%< Number of bytes received */
 148
 149         isc_time_t              start;          /*%< Start time of the transfer */
 150         isc_time_t              end;            /*%< End time of the transfer */
 151
 152         dns_tsigkey_t           *tsigkey;       /*%< Key used to create TSIG */
 153         isc_buffer_t            *lasttsig;      /*%< The last TSIG */
 154         dst_context_t           *tsigctx;       /*%< TSIG verification context */
 155         unsigned int            sincetsig;      /*%< recvd since the last TSIG */
 156         dns_xfrindone_t         done;
 157
 158         /*%
 159          * AXFR- and IXFR-specific data.  Only one is used at a time
 160          * according to the is_ixfr flag, so this could be a union,
 161          * but keeping them separate makes it a bit simpler to clean
 162          * things up when destroying the context.
 163          */
 164         struct {
 165                 dns_addrdatasetfunc_t add_func;
 166                 dns_dbload_t          *add_private;
 167         } axfr;
 168
 169         struct {
 170                 isc_uint32_t    request_serial;
 171                 isc_uint32_t    current_serial;
 172                 dns_journal_t   *journal;
 173
 174         } ixfr;
 175 };
 176
 177 #define XFRIN_MAGIC               ISC_MAGIC('X', 'f', 'r', 'I')
 178 #define VALID_XFRIN(x)            ISC_MAGIC_VALID(x, XFRIN_MAGIC)
 179
 180 /**************************************************************************/
 181 /*
 182  * Forward declarations.
 183  */
 184
 185 static isc_result_t
 186 xfrin_create(isc_mem_t *mctx,
 187              dns_zone_t *zone,
 188              dns_db_t *db,
 189              isc_task_t *task,
 190              isc_timermgr_t *timermgr,
 191              isc_socketmgr_t *socketmgr,
 192              dns_name_t *zonename,
 193              dns_rdataclass_t rdclass,
 194              dns_rdatatype_t reqtype,
 195              isc_sockaddr_t *masteraddr,
 196              isc_sockaddr_t *sourceaddr,
 197              dns_tsigkey_t *tsigkey,
 198              dns_xfrin_ctx_t **xfrp);
 199
 200 static isc_result_t axfr_init(dns_xfrin_ctx_t *xfr);
 201 static isc_result_t axfr_makedb(dns_xfrin_ctx_t *xfr, dns_db_t **dbp);
 202 static isc_result_t axfr_putdata(dns_xfrin_ctx_t *xfr, dns_diffop_t op,
 203                                    dns_name_t *name, dns_ttl_t ttl,
 204                                    dns_rdata_t *rdata);
 205 static isc_result_t axfr_apply(dns_xfrin_ctx_t *xfr);
 206 static isc_result_t axfr_commit(dns_xfrin_ctx_t *xfr);
 207 static isc_result_t axfr_finalize(dns_xfrin_ctx_t *xfr);
 208
 209 static isc_result_t ixfr_init(dns_xfrin_ctx_t *xfr);
 210 static isc_result_t ixfr_apply(dns_xfrin_ctx_t *xfr);
 211 static isc_result_t ixfr_putdata(dns_xfrin_ctx_t *xfr, dns_diffop_t op,
 212                                  dns_name_t *name, dns_ttl_t ttl,
 213                                  dns_rdata_t *rdata);
 214 static isc_result_t ixfr_commit(dns_xfrin_ctx_t *xfr);
 215
 216 static isc_result_t xfr_rr(dns_xfrin_ctx_t *xfr, dns_name_t *name,
 217                            isc_uint32_t ttl, dns_rdata_t *rdata);
 218
 219 static isc_result_t xfrin_start(dns_xfrin_ctx_t *xfr);
 220
 221 static void xfrin_connect_done(isc_task_t *task, isc_event_t *event);
 222 static isc_result_t xfrin_send_request(dns_xfrin_ctx_t *xfr);
 223 static void xfrin_send_done(isc_task_t *task, isc_event_t *event);
 224 static void xfrin_recv_done(isc_task_t *task, isc_event_t *event);
 225 static void xfrin_timeout(isc_task_t *task, isc_event_t *event);
 226
 227 static void maybe_free(dns_xfrin_ctx_t *xfr);
 228
 229 static void
 230 xfrin_fail(dns_xfrin_ctx_t *xfr, isc_result_t result, const char *msg);
 231 static isc_result_t
 232 render(dns_message_t *msg, isc_mem_t *mctx, isc_buffer_t *buf);
 233
 234 static void
 235 xfrin_logv(int level, const char *zonetext, isc_sockaddr_t *masteraddr,
 236            const char *fmt, va_list ap)
 237      ISC_FORMAT_PRINTF(4, 0);
 238
 239 static void
 240 xfrin_log1(int level, const char *zonetext, isc_sockaddr_t *masteraddr,
 241            const char *fmt, ...)
 242      ISC_FORMAT_PRINTF(4, 5);
 243
 244 static void
 245 xfrin_log(dns_xfrin_ctx_t *xfr, int level, const char *fmt, ...)
 246      ISC_FORMAT_PRINTF(3, 4);
 247
 248 /**************************************************************************/
 249 /*
 250  * AXFR handling
 251  */
 252
 253 static isc_result_t
 254 axfr_init(dns_xfrin_ctx_t *xfr) {
 255         isc_result_t result;
 256
 257         xfr->is_ixfr = ISC_FALSE;
 258
 259         if (xfr->db != NULL)
 260                 dns_db_detach(&xfr->db);
 261
 262         CHECK(axfr_makedb(xfr, &xfr->db));
 263         CHECK(dns_db_beginload(xfr->db, &xfr->axfr.add_func,
 264                                &xfr->axfr.add_private));
 265         result = ISC_R_SUCCESS;
 266  failure:
 267         return (result);
 268 }
 269
 270 static isc_result_t
 271 axfr_makedb(dns_xfrin_ctx_t *xfr, dns_db_t **dbp) {
 272         isc_result_t result;
 273
 274         result = dns_db_create(xfr->mctx, /* XXX */
 275                                "rbt",   /* XXX guess */
 276                                &xfr->name,
 277                                dns_dbtype_zone,
 278                                xfr->rdclass,
 279                                0, NULL, /* XXX guess */
 280                                dbp);
 281         if (result == ISC_R_SUCCESS)
 282                 result = dns_zone_rpz_enable_db(xfr->zone, *dbp);
 283         return (result);
 284 }
 285
 286 static isc_result_t
 287 axfr_putdata(dns_xfrin_ctx_t *xfr, dns_diffop_t op,
 288              dns_name_t *name, dns_ttl_t ttl, dns_rdata_t *rdata)
 289 {
 290         isc_result_t result;
 291
 292         dns_difftuple_t *tuple = NULL;
 293
 294         CHECK(dns_zone_checknames(xfr->zone, name, rdata));
 295         CHECK(dns_difftuple_create(xfr->diff.mctx, op,
 296                                    name, ttl, rdata, &tuple));
 297         dns_diff_append(&xfr->diff, &tuple);
 298         if (++xfr->difflen > 100)
 299                 CHECK(axfr_apply(xfr));
 300         result = ISC_R_SUCCESS;
 301  failure:
 302         return (result);
 303 }
 304
 305 /*
 306  * Store a set of AXFR RRs in the database.
 307  */
 308 static isc_result_t
 309 axfr_apply(dns_xfrin_ctx_t *xfr) {
 310         isc_result_t result;
 311
 312         CHECK(dns_diff_load(&xfr->diff,
 313                             xfr->axfr.add_func, xfr->axfr.add_private));
 314         xfr->difflen = 0;
 315         dns_diff_clear(&xfr->diff);
 316         result = ISC_R_SUCCESS;
 317  failure:
 318         return (result);
 319 }
 320
 321 static isc_result_t
 322 axfr_commit(dns_xfrin_ctx_t *xfr) {
 323         isc_result_t result;
 324
 325         CHECK(axfr_apply(xfr));
 326         CHECK(dns_db_endload(xfr->db, &xfr->axfr.add_private));
 327
 328         result = ISC_R_SUCCESS;
 329  failure:
 330         return (result);
 331 }
 332
 333 static isc_result_t
 334 axfr_finalize(dns_xfrin_ctx_t *xfr) {
 335         isc_result_t result;
 336
 337         CHECK(dns_zone_replacedb(xfr->zone, xfr->db, ISC_TRUE));
 338
 339         result = ISC_R_SUCCESS;
 340  failure:
 341         return (result);
 342 }
 343
 344 /**************************************************************************/
 345 /*
 346  * IXFR handling
 347  */
 348
 349 static isc_result_t
 350 ixfr_init(dns_xfrin_ctx_t *xfr) {
 351         isc_result_t result;
 352         char *journalfile;
 353
 354         if (xfr->reqtype != dns_rdatatype_ixfr) {
 355                 xfrin_log(xfr, ISC_LOG_ERROR,
 356                           "got incremental response to AXFR request");
 357                 return (DNS_R_FORMERR);
 358         }
 359
 360         xfr->is_ixfr = ISC_TRUE;
 361         INSIST(xfr->db != NULL);
 362         xfr->difflen = 0;
 363
 364         journalfile = dns_zone_getjournal(xfr->zone);
 365         if (journalfile != NULL)
 366                 CHECK(dns_journal_open(xfr->mctx, journalfile,
 367                                        ISC_TRUE, &xfr->ixfr.journal));
 368
 369         result = ISC_R_SUCCESS;
 370  failure:
 371         return (result);
 372 }
 373
 374 static isc_result_t
 375 ixfr_putdata(dns_xfrin_ctx_t *xfr, dns_diffop_t op,
 376              dns_name_t *name, dns_ttl_t ttl, dns_rdata_t *rdata)
 377 {
 378         isc_result_t result;
 379
 380         dns_difftuple_t *tuple = NULL;
 381         if (op == DNS_DIFFOP_ADD)
 382                 CHECK(dns_zone_checknames(xfr->zone, name, rdata));
 383         CHECK(dns_difftuple_create(xfr->diff.mctx, op,
 384                                    name, ttl, rdata, &tuple));
 385         dns_diff_append(&xfr->diff, &tuple);
 386         if (++xfr->difflen > 100)
 387                 CHECK(ixfr_apply(xfr));
 388         result = ISC_R_SUCCESS;
 389  failure:
 390         return (result);
 391 }
 392
 393 /*
 394  * Apply a set of IXFR changes to the database.
 395  */
 396 static isc_result_t
 397 ixfr_apply(dns_xfrin_ctx_t *xfr) {
 398         isc_result_t result;
 399
 400         if (xfr->ver == NULL) {
 401                 CHECK(dns_db_newversion(xfr->db, &xfr->ver));
 402                 if (xfr->ixfr.journal != NULL)
 403                         CHECK(dns_journal_begin_transaction(xfr->ixfr.journal));
 404         }
 405         CHECK(dns_diff_apply(&xfr->diff, xfr->db, xfr->ver));
 406         if (xfr->ixfr.journal != NULL) {
 407                 result = dns_journal_writediff(xfr->ixfr.journal, &xfr->diff);
 408                 if (result != ISC_R_SUCCESS)
 409                         goto failure;
 410         }
 411         dns_diff_clear(&xfr->diff);
 412         xfr->difflen = 0;
 413         result = ISC_R_SUCCESS;
 414  failure:
 415         return (result);
 416 }
 417
 418 static isc_result_t
 419 ixfr_commit(dns_xfrin_ctx_t *xfr) {
 420         isc_result_t result;
 421
 422         CHECK(ixfr_apply(xfr));
 423         if (xfr->ver != NULL) {
 424                 /* XXX enter ready-to-commit state here */
 425                 if (xfr->ixfr.journal != NULL)
 426                         CHECK(dns_journal_commit(xfr->ixfr.journal));
 427                 dns_db_closeversion(xfr->db, &xfr->ver, ISC_TRUE);
 428                 dns_zone_markdirty(xfr->zone);
 429         }
 430         result = ISC_R_SUCCESS;
 431  failure:
 432         return (result);
 433 }
 434
 435 /**************************************************************************/
 436 /*
 437  * Common AXFR/IXFR protocol code
 438  */
 439
 440 /*
 441  * Handle a single incoming resource record according to the current
 442  * state.
 443  */
 444 static isc_result_t
 445 xfr_rr(dns_xfrin_ctx_t *xfr, dns_name_t *name, isc_uint32_t ttl,
 446        dns_rdata_t *rdata)
 447 {
 448         isc_result_t result;
 449
 450         xfr->nrecs++;
 451
 452         if (rdata->type == dns_rdatatype_none ||
 453             dns_rdatatype_ismeta(rdata->type))
 454                 FAIL(DNS_R_FORMERR);
 455
 456  redo:
 457         switch (xfr->state) {
 458         case XFRST_SOAQUERY:
 459                 if (rdata->type != dns_rdatatype_soa) {
 460                         xfrin_log(xfr, ISC_LOG_ERROR,
 461                                   "non-SOA response to SOA query");
 462                         FAIL(DNS_R_FORMERR);
 463                 }
 464                 xfr->end_serial = dns_soa_getserial(rdata);
 465                 if (!DNS_SERIAL_GT(xfr->end_serial, xfr->ixfr.request_serial) &&
 466                     !dns_zone_isforced(xfr->zone)) {
 467                         xfrin_log(xfr, ISC_LOG_DEBUG(3),
 468                                   "requested serial %u, "
 469                                   "master has %u, not updating",
 470                                   xfr->ixfr.request_serial, xfr->end_serial);
 471                         FAIL(DNS_R_UPTODATE);
 472                 }
 473                 xfr->state = XFRST_GOTSOA;
 474                 break;
 475
 476         case XFRST_GOTSOA:
 477                 /*
 478                  * Skip other records in the answer section.
 479                  */
 480                 break;
 481
 482         case XFRST_INITIALSOA:
 483                 if (rdata->type != dns_rdatatype_soa) {
 484                         xfrin_log(xfr, ISC_LOG_ERROR,
 485                                   "first RR in zone transfer must be SOA");
 486                         FAIL(DNS_R_FORMERR);
 487                 }
 488                 /*
 489                  * Remember the serial number in the initial SOA.
 490                  * We need it to recognize the end of an IXFR.
 491                  */
 492                 xfr->end_serial = dns_soa_getserial(rdata);
 493                 if (xfr->reqtype == dns_rdatatype_ixfr &&
 494                     ! DNS_SERIAL_GT(xfr->end_serial, xfr->ixfr.request_serial)
 495                     && !dns_zone_isforced(xfr->zone))
 496                 {
 497                         /*
 498                          * This must be the single SOA record that is
 499                          * sent when the current version on the master
 500                          * is not newer than the version in the request.
 501                          */
 502                         xfrin_log(xfr, ISC_LOG_DEBUG(3),
 503                                   "requested serial %u, "
 504                                   "master has %u, not updating",
 505                                   xfr->ixfr.request_serial, xfr->end_serial);
 506                         FAIL(DNS_R_UPTODATE);
 507                 }
 508                 if (xfr->reqtype == dns_rdatatype_axfr)
 509                         xfr->checkid = ISC_FALSE;
 510                 xfr->state = XFRST_FIRSTDATA;
 511                 break;
 512
 513         case XFRST_FIRSTDATA:
 514                 /*
 515                  * If the transfer begins with one SOA record, it is an AXFR,
 516                  * if it begins with two SOAs, it is an IXFR.
 517                  */
 518                 if (xfr->reqtype == dns_rdatatype_ixfr &&
 519                     rdata->type == dns_rdatatype_soa &&
 520                     xfr->ixfr.request_serial == dns_soa_getserial(rdata)) {
 521                         xfrin_log(xfr, ISC_LOG_DEBUG(3),
 522                                   "got incremental response");
 523                         CHECK(ixfr_init(xfr));
 524                         xfr->state = XFRST_IXFR_DELSOA;
 525                 } else {
 526                         xfrin_log(xfr, ISC_LOG_DEBUG(3),
 527                                   "got nonincremental response");
 528                         CHECK(axfr_init(xfr));
 529                         xfr->state = XFRST_AXFR;
 530                 }
 531                 goto redo;
 532
 533         case XFRST_IXFR_DELSOA:
 534                 INSIST(rdata->type == dns_rdatatype_soa);
 535                 CHECK(ixfr_putdata(xfr, DNS_DIFFOP_DEL, name, ttl, rdata));
 536                 xfr->state = XFRST_IXFR_DEL;
 537                 break;
 538
 539         case XFRST_IXFR_DEL:
 540                 if (rdata->type == dns_rdatatype_soa) {
 541                         isc_uint32_t soa_serial = dns_soa_getserial(rdata);
 542                         xfr->state = XFRST_IXFR_ADDSOA;
 543                         xfr->ixfr.current_serial = soa_serial;
 544                         goto redo;
 545                 }
 546                 CHECK(ixfr_putdata(xfr, DNS_DIFFOP_DEL, name, ttl, rdata));
 547                 break;
 548
 549         case XFRST_IXFR_ADDSOA:
 550                 INSIST(rdata->type == dns_rdatatype_soa);
 551                 CHECK(ixfr_putdata(xfr, DNS_DIFFOP_ADD, name, ttl, rdata));
 552                 xfr->state = XFRST_IXFR_ADD;
 553                 break;
 554
 555         case XFRST_IXFR_ADD:
 556                 if (rdata->type == dns_rdatatype_soa) {
 557                         isc_uint32_t soa_serial = dns_soa_getserial(rdata);
 558                         if (soa_serial == xfr->end_serial) {
 559                                 CHECK(ixfr_commit(xfr));
 560                                 xfr->state = XFRST_IXFR_END;
 561                                 break;
 562                         } else if (soa_serial != xfr->ixfr.current_serial) {
 563                                 xfrin_log(xfr, ISC_LOG_ERROR,
 564                                           "IXFR out of sync: "
 565                                           "expected serial %u, got %u",
 566                                           xfr->ixfr.current_serial, soa_serial);
 567                                 FAIL(DNS_R_FORMERR);
 568                         } else {
 569                                 CHECK(ixfr_commit(xfr));
 570                                 xfr->state = XFRST_IXFR_DELSOA;
 571                                 goto redo;
 572                         }
 573                 }
 574                 if (rdata->type == dns_rdatatype_ns &&
 575                     dns_name_iswildcard(name))
 576                         FAIL(DNS_R_INVALIDNS);
 577                 CHECK(ixfr_putdata(xfr, DNS_DIFFOP_ADD, name, ttl, rdata));
 578                 break;
 579
 580         case XFRST_AXFR:
 581                 /*
 582                  * Old BINDs sent cross class A records for non IN classes.
 583                  */
 584                 if (rdata->type == dns_rdatatype_a &&
 585                     rdata->rdclass != xfr->rdclass &&
 586                     xfr->rdclass != dns_rdataclass_in)
 587                         break;
 588                 CHECK(axfr_putdata(xfr, DNS_DIFFOP_ADD, name, ttl, rdata));
 589                 if (rdata->type == dns_rdatatype_soa) {
 590                         CHECK(axfr_commit(xfr));
 591                         xfr->state = XFRST_AXFR_END;
 592                         break;
 593                 }
 594                 break;
 595         case XFRST_AXFR_END:
 596         case XFRST_IXFR_END:
 597                 FAIL(DNS_R_EXTRADATA);
 598                 /* NOTREACHED */
 599         default:
 600                 INSIST(0);
 601                 break;
 602         }
 603         result = ISC_R_SUCCESS;
 604  failure:
 605         return (result);
 606 }
 607
 608 isc_result_t
 609 dns_xfrin_create(dns_zone_t *zone, dns_rdatatype_t xfrtype,
 610                  isc_sockaddr_t *masteraddr, dns_tsigkey_t *tsigkey,
 611                  isc_mem_t *mctx, isc_timermgr_t *timermgr,
 612                  isc_socketmgr_t *socketmgr, isc_task_t *task,
 613                  dns_xfrindone_t done, dns_xfrin_ctx_t **xfrp)
 614 {
 615         isc_sockaddr_t sourceaddr;
 616
 617         switch (isc_sockaddr_pf(masteraddr)) {
 618         case PF_INET:
 619                 sourceaddr = *dns_zone_getxfrsource4(zone);
 620                 break;
 621         case PF_INET6:
 622                 sourceaddr = *dns_zone_getxfrsource6(zone);
 623                 break;
 624         default:
 625                 INSIST(0);
 626         }
 627
 628         return(dns_xfrin_create2(zone, xfrtype, masteraddr, &sourceaddr,
 629                                  tsigkey, mctx, timermgr, socketmgr,
 630                                  task, done, xfrp));
 631 }
 632
 633 isc_result_t
 634 dns_xfrin_create2(dns_zone_t *zone, dns_rdatatype_t xfrtype,
 635                   isc_sockaddr_t *masteraddr, isc_sockaddr_t *sourceaddr,
 636                   dns_tsigkey_t *tsigkey, isc_mem_t *mctx,
 637                   isc_timermgr_t *timermgr, isc_socketmgr_t *socketmgr,
 638                   isc_task_t *task, dns_xfrindone_t done, dns_xfrin_ctx_t **xfrp)
 639 {
 640         dns_name_t *zonename = dns_zone_getorigin(zone);
 641         dns_xfrin_ctx_t *xfr = NULL;
 642         isc_result_t result;
 643         dns_db_t *db = NULL;
 644
 645         REQUIRE(xfrp != NULL && *xfrp == NULL);
 646
 647         (void)dns_zone_getdb(zone, &db);
 648
 649         if (xfrtype == dns_rdatatype_soa || xfrtype == dns_rdatatype_ixfr)
 650                 REQUIRE(db != NULL);
 651
 652         CHECK(xfrin_create(mctx, zone, db, task, timermgr, socketmgr, zonename,
 653                            dns_zone_getclass(zone), xfrtype, masteraddr,
 654                            sourceaddr, tsigkey, &xfr));
 655
 656         CHECK(xfrin_start(xfr));
 657
 658         xfr->done = done;
 659         xfr->refcount++;
 660         *xfrp = xfr;
 661
 662  failure:
 663         if (db != NULL)
 664                 dns_db_detach(&db);
 665         if (result != ISC_R_SUCCESS) {
 666                 char zonetext[DNS_NAME_MAXTEXT+32];
 667                 dns_zone_name(zone, zonetext, sizeof(zonetext));
 668                 xfrin_log1(ISC_LOG_ERROR, zonetext, masteraddr,
 669                            "zone transfer setup failed");
 670         }
 671         return (result);
 672 }
 673
 674 void
 675 dns_xfrin_shutdown(dns_xfrin_ctx_t *xfr) {
 676         if (! xfr->shuttingdown)
 677                 xfrin_fail(xfr, ISC_R_CANCELED, "shut down");
 678 }
 679
 680 void
 681 dns_xfrin_attach(dns_xfrin_ctx_t *source, dns_xfrin_ctx_t **target) {
 682         REQUIRE(target != NULL && *target == NULL);
 683         source->refcount++;
 684         *target = source;
 685 }
 686
 687 void
 688 dns_xfrin_detach(dns_xfrin_ctx_t **xfrp) {
 689         dns_xfrin_ctx_t *xfr = *xfrp;
 690         INSIST(xfr->refcount > 0);
 691         xfr->refcount--;
 692         maybe_free(xfr);
 693         *xfrp = NULL;
 694 }
 695
 696 static void
 697 xfrin_cancelio(dns_xfrin_ctx_t *xfr) {
 698         if (xfr->connects > 0) {
 699                 isc_socket_cancel(xfr->socket, xfr->task,
 700                                   ISC_SOCKCANCEL_CONNECT);
 701         } else if (xfr->recvs > 0) {
 702                 dns_tcpmsg_cancelread(&xfr->tcpmsg);
 703         } else if (xfr->sends > 0) {
 704                 isc_socket_cancel(xfr->socket, xfr->task,
 705                                   ISC_SOCKCANCEL_SEND);
 706         }
 707 }
 708
 709 static void
 710 xfrin_reset(dns_xfrin_ctx_t *xfr) {
 711         REQUIRE(VALID_XFRIN(xfr));
 712
 713         xfrin_log(xfr, ISC_LOG_INFO, "resetting");
 714
 715         xfrin_cancelio(xfr);
 716
 717         if (xfr->socket != NULL)
 718                 isc_socket_detach(&xfr->socket);
 719
 720         if (xfr->lasttsig != NULL)
 721                 isc_buffer_free(&xfr->lasttsig);
 722
 723         dns_diff_clear(&xfr->diff);
 724         xfr->difflen = 0;
 725
 726         if (xfr->ixfr.journal != NULL)
 727                 dns_journal_destroy(&xfr->ixfr.journal);
 728
 729         if (xfr->axfr.add_private != NULL) {
 730                 (void)dns_db_endload(xfr->db, &xfr->axfr.add_private);
 731                 xfr->axfr.add_func = NULL;
 732         }
 733
 734         if (xfr->tcpmsg_valid) {
 735                 dns_tcpmsg_invalidate(&xfr->tcpmsg);
 736                 xfr->tcpmsg_valid = ISC_FALSE;
 737         }
 738
 739         if (xfr->ver != NULL)
 740                 dns_db_closeversion(xfr->db, &xfr->ver, ISC_FALSE);
 741 }
 742
 743
 744 static void
 745 xfrin_fail(dns_xfrin_ctx_t *xfr, isc_result_t result, const char *msg) {
 746         if (result != DNS_R_UPTODATE) {
 747                 xfrin_log(xfr, ISC_LOG_ERROR, "%s: %s",
 748                           msg, isc_result_totext(result));
 749                 if (xfr->is_ixfr)
 750                         /* Pass special result code to force AXFR retry */
 751                         result = DNS_R_BADIXFR;
 752         }
 753         xfrin_cancelio(xfr);
 754         /*
 755          * Close the journal.
 756          */
 757         if (xfr->ixfr.journal != NULL)
 758                 dns_journal_destroy(&xfr->ixfr.journal);
 759         if (xfr->done != NULL) {
 760                 (xfr->done)(xfr->zone, result);
 761                 xfr->done = NULL;
 762         }
 763         xfr->shuttingdown = ISC_TRUE;
 764         maybe_free(xfr);
 765 }
 766
 767 static isc_result_t
 768 xfrin_create(isc_mem_t *mctx,
 769              dns_zone_t *zone,
 770              dns_db_t *db,
 771              isc_task_t *task,
 772              isc_timermgr_t *timermgr,
 773              isc_socketmgr_t *socketmgr,
 774              dns_name_t *zonename,
 775              dns_rdataclass_t rdclass,
 776              dns_rdatatype_t reqtype,
 777              isc_sockaddr_t *masteraddr,
 778              isc_sockaddr_t *sourceaddr,
 779              dns_tsigkey_t *tsigkey,
 780              dns_xfrin_ctx_t **xfrp)
 781 {
 782         dns_xfrin_ctx_t *xfr = NULL;
 783         isc_result_t result;
 784         isc_uint32_t tmp;
 785
 786         xfr = isc_mem_get(mctx, sizeof(*xfr));
 787         if (xfr == NULL)
 788                 return (ISC_R_NOMEMORY);
 789         xfr->mctx = NULL;
 790         isc_mem_attach(mctx, &xfr->mctx);
 791         xfr->refcount = 0;
 792         xfr->zone = NULL;
 793         dns_zone_iattach(zone, &xfr->zone);
 794         xfr->task = NULL;
 795         isc_task_attach(task, &xfr->task);
 796         xfr->timer = NULL;
 797         xfr->socketmgr = socketmgr;
 798         xfr->done = NULL;
 799
 800         xfr->connects = 0;
 801         xfr->sends = 0;
 802         xfr->recvs = 0;
 803         xfr->shuttingdown = ISC_FALSE;
 804
 805         dns_name_init(&xfr->name, NULL);
 806         xfr->rdclass = rdclass;
 807         isc_random_get(&tmp);
 808         xfr->checkid = ISC_TRUE;
 809         xfr->id = (isc_uint16_t)(tmp & 0xffff);
 810         xfr->reqtype = reqtype;
 811
 812         /* sockaddr */
 813         xfr->socket = NULL;
 814         /* qbuffer */
 815         /* qbuffer_data */
 816         /* tcpmsg */
 817         xfr->tcpmsg_valid = ISC_FALSE;
 818
 819         xfr->db = NULL;
 820         if (db != NULL)
 821                 dns_db_attach(db, &xfr->db);
 822         xfr->ver = NULL;
 823         dns_diff_init(xfr->mctx, &xfr->diff);
 824         xfr->difflen = 0;
 825
 826         if (reqtype == dns_rdatatype_soa)
 827                 xfr->state = XFRST_SOAQUERY;
 828         else
 829                 xfr->state = XFRST_INITIALSOA;
 830         /* end_serial */
 831
 832         xfr->nmsg = 0;
 833         xfr->nrecs = 0;
 834         xfr->nbytes = 0;
 835         isc_time_now(&xfr->start);
 836
 837         xfr->tsigkey = NULL;
 838         if (tsigkey != NULL)
 839                 dns_tsigkey_attach(tsigkey, &xfr->tsigkey);
 840         xfr->lasttsig = NULL;
 841         xfr->tsigctx = NULL;
 842         xfr->sincetsig = 0;
 843         xfr->is_ixfr = ISC_FALSE;
 844
 845         /* ixfr.request_serial */
 846         /* ixfr.current_serial */
 847         xfr->ixfr.journal = NULL;
 848
 849         xfr->axfr.add_func = NULL;
 850         xfr->axfr.add_private = NULL;
 851
 852         CHECK(dns_name_dup(zonename, mctx, &xfr->name));
 853
 854         CHECK(isc_timer_create(timermgr, isc_timertype_inactive, NULL, NULL,
 855                                task, xfrin_timeout, xfr, &xfr->timer));
 856         CHECK(dns_timer_setidle(xfr->timer,
 857                                 dns_zone_getmaxxfrin(xfr->zone),
 858                                 dns_zone_getidlein(xfr->zone),
 859                                 ISC_FALSE));
 860
 861         xfr->masteraddr = *masteraddr;
 862
 863         INSIST(isc_sockaddr_pf(masteraddr) == isc_sockaddr_pf(sourceaddr));
 864         xfr->sourceaddr = *sourceaddr;
 865         isc_sockaddr_setport(&xfr->sourceaddr, 0);
 866
 867         /*
 868          * Reserve 2 bytes for TCP length at the begining of the buffer.
 869          */
 870         isc_buffer_init(&xfr->qbuffer, &xfr->qbuffer_data[2],
 871                         sizeof(xfr->qbuffer_data) - 2);
 872
 873         xfr->magic = XFRIN_MAGIC;
 874         *xfrp = xfr;
 875         return (ISC_R_SUCCESS);
 876
 877  failure:
 878         if (xfr->timer != NULL)
 879                 isc_timer_detach(&xfr->timer);
 880         if (dns_name_dynamic(&xfr->name))
 881                 dns_name_free(&xfr->name, xfr->mctx);
 882         if (xfr->tsigkey != NULL)
 883                 dns_tsigkey_detach(&xfr->tsigkey);
 884         if (xfr->db != NULL)
 885                 dns_db_detach(&xfr->db);
 886         isc_task_detach(&xfr->task);
 887         dns_zone_idetach(&xfr->zone);
 888         isc_mem_putanddetach(&xfr->mctx, xfr, sizeof(*xfr));
 889
 890         return (result);
 891 }
 892
 893 static isc_result_t
 894 xfrin_start(dns_xfrin_ctx_t *xfr) {
 895         isc_result_t result;
 896         CHECK(isc_socket_create(xfr->socketmgr,
 897                                 isc_sockaddr_pf(&xfr->sourceaddr),
 898                                 isc_sockettype_tcp,
 899                                 &xfr->socket));
 900         isc_socket_setname(xfr->socket, "xfrin", NULL);
 901 #ifndef BROKEN_TCP_BIND_BEFORE_CONNECT
 902         CHECK(isc_socket_bind(xfr->socket, &xfr->sourceaddr,
 903                               ISC_SOCKET_REUSEADDRESS));
 904 #endif
 905         CHECK(isc_socket_connect(xfr->socket, &xfr->masteraddr, xfr->task,
 906                                  xfrin_connect_done, xfr));
 907         xfr->connects++;
 908         return (ISC_R_SUCCESS);
 909  failure:
 910         xfrin_fail(xfr, result, "failed setting up socket");
 911         return (result);
 912 }
 913
 914 /* XXX the resolver could use this, too */
 915
 916 static isc_result_t
 917 render(dns_message_t *msg, isc_mem_t *mctx, isc_buffer_t *buf) {
 918         dns_compress_t cctx;
 919         isc_boolean_t cleanup_cctx = ISC_FALSE;
 920         isc_result_t result;
 921
 922         CHECK(dns_compress_init(&cctx, -1, mctx));
 923         cleanup_cctx = ISC_TRUE;
 924         CHECK(dns_message_renderbegin(msg, &cctx, buf));
 925         CHECK(dns_message_rendersection(msg, DNS_SECTION_QUESTION, 0));
 926         CHECK(dns_message_rendersection(msg, DNS_SECTION_ANSWER, 0));
 927         CHECK(dns_message_rendersection(msg, DNS_SECTION_AUTHORITY, 0));
 928         CHECK(dns_message_rendersection(msg, DNS_SECTION_ADDITIONAL, 0));
 929         CHECK(dns_message_renderend(msg));
 930         result = ISC_R_SUCCESS;
 931  failure:
 932         if (cleanup_cctx)
 933                 dns_compress_invalidate(&cctx);
 934         return (result);
 935 }
 936
 937 /*
 938  * A connection has been established.
 939  */
 940 static void
 941 xfrin_connect_done(isc_task_t *task, isc_event_t *event) {
 942         isc_socket_connev_t *cev = (isc_socket_connev_t *) event;
 943         dns_xfrin_ctx_t *xfr = (dns_xfrin_ctx_t *) event->ev_arg;
 944         isc_result_t result = cev->result;
 945         char sourcetext[ISC_SOCKADDR_FORMATSIZE];
 946         isc_sockaddr_t sockaddr;
 947         dns_zonemgr_t * zmgr;
 948         isc_time_t now;
 949
 950         REQUIRE(VALID_XFRIN(xfr));
 951
 952         UNUSED(task);
 953
 954         INSIST(event->ev_type == ISC_SOCKEVENT_CONNECT);
 955         isc_event_free(&event);
 956
 957         xfr->connects--;
 958         if (xfr->shuttingdown) {
 959                 maybe_free(xfr);
 960                 return;
 961         }
 962
 963         zmgr = dns_zone_getmgr(xfr->zone);
 964         if (zmgr != NULL) {
 965                 if (result != ISC_R_SUCCESS) {
 966                         TIME_NOW(&now);
 967                         dns_zonemgr_unreachableadd(zmgr, &xfr->masteraddr,
 968                                                    &xfr->sourceaddr, &now);
 969                         goto failure;
 970                 } else
 971                         dns_zonemgr_unreachabledel(zmgr, &xfr->masteraddr,
 972                                                    &xfr->sourceaddr);
 973         }
 974
 975         result = isc_socket_getsockname(xfr->socket, &sockaddr);
 976         if (result == ISC_R_SUCCESS) {
 977                 isc_sockaddr_format(&sockaddr, sourcetext, sizeof(sourcetext));
 978         } else
 979                 strcpy(sourcetext, "<UNKNOWN>");
 980         xfrin_log(xfr, ISC_LOG_INFO, "connected using %s", sourcetext);
 981
 982         dns_tcpmsg_init(xfr->mctx, xfr->socket, &xfr->tcpmsg);
 983         xfr->tcpmsg_valid = ISC_TRUE;
 984
 985         CHECK(xfrin_send_request(xfr));
 986  failure:
 987         if (result != ISC_R_SUCCESS)
 988                 xfrin_fail(xfr, result, "failed to connect");
 989 }
 990
 991 /*
 992  * Convert a tuple into a dns_name_t suitable for inserting
 993  * into the given dns_message_t.
 994  */
 995 static isc_result_t
 996 tuple2msgname(dns_difftuple_t *tuple, dns_message_t *msg, dns_name_t **target)
 997 {
 998         isc_result_t result;
 999         dns_rdata_t *rdata = NULL;
1000         dns_rdatalist_t *rdl = NULL;
1001         dns_rdataset_t *rds = NULL;
1002         dns_name_t *name = NULL;
1003
1004         REQUIRE(target != NULL && *target == NULL);
1005
1006         CHECK(dns_message_gettemprdata(msg, &rdata));
1007         dns_rdata_init(rdata);
1008         dns_rdata_clone(&tuple->rdata, rdata);
1009
1010         CHECK(dns_message_gettemprdatalist(msg, &rdl));
1011         dns_rdatalist_init(rdl);
1012         rdl->type = tuple->rdata.type;
1013         rdl->rdclass = tuple->rdata.rdclass;
1014         rdl->ttl = tuple->ttl;
1015         ISC_LIST_APPEND(rdl->rdata, rdata, link);
1016
1017         CHECK(dns_message_gettemprdataset(msg, &rds));
1018         dns_rdataset_init(rds);
1019         CHECK(dns_rdatalist_tordataset(rdl, rds));
1020
1021         CHECK(dns_message_gettempname(msg, &name));
1022         dns_name_init(name, NULL);
1023         dns_name_clone(&tuple->name, name);
1024         ISC_LIST_APPEND(name->list, rds, link);
1025
1026         *target = name;
1027         return (ISC_R_SUCCESS);
1028
1029  failure:
1030
1031         if (rds != NULL) {
1032                 dns_rdataset_disassociate(rds);
1033                 dns_message_puttemprdataset(msg, &rds);
1034         }
1035         if (rdl != NULL) {
1036                 ISC_LIST_UNLINK(rdl->rdata, rdata, link);
1037                 dns_message_puttemprdatalist(msg, &rdl);
1038         }
1039         if (rdata != NULL)
1040                 dns_message_puttemprdata(msg, &rdata);
1041
1042         return (result);
1043 }
1044
1045
1046 /*
1047  * Build an *XFR request and send its length prefix.
1048  */
1049 static isc_result_t
1050 xfrin_send_request(dns_xfrin_ctx_t *xfr) {
1051         isc_result_t result;
1052         isc_region_t region;
1053         dns_rdataset_t *qrdataset = NULL;
1054         dns_message_t *msg = NULL;
1055         dns_difftuple_t *soatuple = NULL;
1056         dns_name_t *qname = NULL;
1057         dns_dbversion_t *ver = NULL;
1058         dns_name_t *msgsoaname = NULL;
1059
1060         /* Create the request message */
1061         CHECK(dns_message_create(xfr->mctx, DNS_MESSAGE_INTENTRENDER, &msg));
1062         CHECK(dns_message_settsigkey(msg, xfr->tsigkey));
1063
1064         /* Create a name for the question section. */
1065         CHECK(dns_message_gettempname(msg, &qname));
1066         dns_name_init(qname, NULL);
1067         dns_name_clone(&xfr->name, qname);
1068
1069         /* Formulate the question and attach it to the question name. */
1070         CHECK(dns_message_gettemprdataset(msg, &qrdataset));
1071         dns_rdataset_init(qrdataset);
1072         dns_rdataset_makequestion(qrdataset, xfr->rdclass, xfr->reqtype);
1073         ISC_LIST_APPEND(qname->list, qrdataset, link);
1074         qrdataset = NULL;
1075
1076         dns_message_addname(msg, qname, DNS_SECTION_QUESTION);
1077         qname = NULL;
1078
1079         if (xfr->reqtype == dns_rdatatype_ixfr) {
1080                 /* Get the SOA and add it to the authority section. */
1081                 /* XXX is using the current version the right thing? */
1082                 dns_db_currentversion(xfr->db, &ver);
1083                 CHECK(dns_db_createsoatuple(xfr->db, ver, xfr->mctx,
1084                                             DNS_DIFFOP_EXISTS, &soatuple));
1085                 xfr->ixfr.request_serial = dns_soa_getserial(&soatuple->rdata);
1086                 xfr->ixfr.current_serial = xfr->ixfr.request_serial;
1087                 xfrin_log(xfr, ISC_LOG_DEBUG(3),
1088                           "requesting IXFR for serial %u",
1089                           xfr->ixfr.request_serial);
1090
1091                 CHECK(tuple2msgname(soatuple, msg, &msgsoaname));
1092                 dns_message_addname(msg, msgsoaname, DNS_SECTION_AUTHORITY);
1093         } else if (xfr->reqtype == dns_rdatatype_soa)
1094                 CHECK(dns_db_getsoaserial(xfr->db, NULL,
1095                                           &xfr->ixfr.request_serial));
1096
1097         xfr->checkid = ISC_TRUE;
1098         xfr->id++;
1099         xfr->nmsg = 0;
1100         xfr->nrecs = 0;
1101         xfr->nbytes = 0;
1102         isc_time_now(&xfr->start);
1103         msg->id = xfr->id;
1104         if (xfr->tsigctx != NULL)
1105                 dst_context_destroy(&xfr->tsigctx);
1106
1107         CHECK(render(msg, xfr->mctx, &xfr->qbuffer));
1108
1109         /*
1110          * Free the last tsig, if there is one.
1111          */
1112         if (xfr->lasttsig != NULL)
1113                 isc_buffer_free(&xfr->lasttsig);
1114
1115         /*
1116          * Save the query TSIG and don't let message_destroy free it.
1117          */
1118         CHECK(dns_message_getquerytsig(msg, xfr->mctx, &xfr->lasttsig));
1119
1120         isc_buffer_usedregion(&xfr->qbuffer, &region);
1121         INSIST(region.length <= 65535);
1122
1123         /*
1124          * Record message length and adjust region to include TCP
1125          * length field.
1126          */
1127         xfr->qbuffer_data[0] = (region.length >> 8) & 0xff;
1128         xfr->qbuffer_data[1] = region.length & 0xff;
1129         region.base -= 2;
1130         region.length += 2;
1131         CHECK(isc_socket_send(xfr->socket, &region, xfr->task,
1132                               xfrin_send_done, xfr));
1133         xfr->sends++;
1134
1135  failure:
1136         if (qname != NULL)
1137                 dns_message_puttempname(msg, &qname);
1138         if (qrdataset != NULL)
1139                 dns_message_puttemprdataset(msg, &qrdataset);
1140         if (msg != NULL)
1141                 dns_message_destroy(&msg);
1142         if (soatuple != NULL)
1143                 dns_difftuple_free(&soatuple);
1144         if (ver != NULL)
1145                 dns_db_closeversion(xfr->db, &ver, ISC_FALSE);
1146         return (result);
1147 }
1148
1149 static void
1150 xfrin_send_done(isc_task_t *task, isc_event_t *event) {
1151         isc_socketevent_t *sev = (isc_socketevent_t *) event;
1152         dns_xfrin_ctx_t *xfr = (dns_xfrin_ctx_t *) event->ev_arg;
1153         isc_result_t result;
1154
1155         REQUIRE(VALID_XFRIN(xfr));
1156
1157         UNUSED(task);
1158
1159         INSIST(event->ev_type == ISC_SOCKEVENT_SENDDONE);
1160
1161         xfr->sends--;
1162         xfrin_log(xfr, ISC_LOG_DEBUG(3), "sent request data");
1163         CHECK(sev->result);
1164
1165         CHECK(dns_tcpmsg_readmessage(&xfr->tcpmsg, xfr->task,
1166                                      xfrin_recv_done, xfr));
1167         xfr->recvs++;
1168  failure:
1169         isc_event_free(&event);
1170         if (result != ISC_R_SUCCESS)
1171                 xfrin_fail(xfr, result, "failed sending request data");
1172 }
1173
1174
1175 static void
1176 xfrin_recv_done(isc_task_t *task, isc_event_t *ev) {
1177         dns_xfrin_ctx_t *xfr = (dns_xfrin_ctx_t *) ev->ev_arg;
1178         isc_result_t result;
1179         dns_message_t *msg = NULL;
1180         dns_name_t *name;
1181         dns_tcpmsg_t *tcpmsg;
1182         dns_name_t *tsigowner = NULL;
1183
1184         REQUIRE(VALID_XFRIN(xfr));
1185
1186         UNUSED(task);
1187
1188         INSIST(ev->ev_type == DNS_EVENT_TCPMSG);
1189         tcpmsg = ev->ev_sender;
1190         isc_event_free(&ev);
1191
1192         xfr->recvs--;
1193         if (xfr->shuttingdown) {
1194                 maybe_free(xfr);
1195                 return;
1196         }
1197
1198         CHECK(tcpmsg->result);
1199
1200         xfrin_log(xfr, ISC_LOG_DEBUG(7), "received %u bytes",
1201                   tcpmsg->buffer.used);
1202
1203         CHECK(isc_timer_touch(xfr->timer));
1204
1205         CHECK(dns_message_create(xfr->mctx, DNS_MESSAGE_INTENTPARSE, &msg));
1206
1207         CHECK(dns_message_settsigkey(msg, xfr->tsigkey));
1208         CHECK(dns_message_setquerytsig(msg, xfr->lasttsig));
1209
1210         msg->tsigctx = xfr->tsigctx;
1211         xfr->tsigctx = NULL;
1212
1213         if (xfr->nmsg > 0)
1214                 msg->tcp_continuation = 1;
1215
1216         result = dns_message_parse(msg, &tcpmsg->buffer,
1217                                    DNS_MESSAGEPARSE_PRESERVEORDER);
1218
1219         if (result != ISC_R_SUCCESS || msg->rcode != dns_rcode_noerror ||
1220             (xfr->checkid && msg->id != xfr->id)) {
1221                 if (result == ISC_R_SUCCESS)
1222                         result = ISC_RESULTCLASS_DNSRCODE + msg->rcode; /*XXX*/
1223                 if (result == ISC_R_SUCCESS || result == DNS_R_NOERROR)
1224                         result = DNS_R_UNEXPECTEDID;
1225                 if (xfr->reqtype == dns_rdatatype_axfr ||
1226                     xfr->reqtype == dns_rdatatype_soa)
1227                         goto failure;
1228                 xfrin_log(xfr, ISC_LOG_DEBUG(3), "got %s, retrying with AXFR",
1229                        isc_result_totext(result));
1230  try_axfr:
1231                 dns_message_destroy(&msg);
1232                 xfrin_reset(xfr);
1233                 xfr->reqtype = dns_rdatatype_soa;
1234                 xfr->state = XFRST_SOAQUERY;
1235                 (void)xfrin_start(xfr);
1236                 return;
1237         }
1238
1239         /*
1240          * Does the server know about IXFR?  If it doesn't we will get
1241          * a message with a empty answer section or a potentially a CNAME /
1242          * DNAME, the later is handled by xfr_rr() which will return FORMERR
1243          * if the first RR in the answer section is not a SOA record.
1244          */
1245         if (xfr->reqtype == dns_rdatatype_ixfr &&
1246             xfr->state == XFRST_INITIALSOA &&
1247             msg->counts[DNS_SECTION_ANSWER] == 0) {
1248                 xfrin_log(xfr, ISC_LOG_DEBUG(3),
1249                           "empty answer section, retrying with AXFR");
1250                 goto try_axfr;
1251         }
1252
1253         if (xfr->reqtype == dns_rdatatype_soa &&
1254             (msg->flags & DNS_MESSAGEFLAG_AA) == 0) {
1255                 FAIL(DNS_R_NOTAUTHORITATIVE);
1256         }
1257
1258
1259         result = dns_message_checksig(msg, dns_zone_getview(xfr->zone));
1260         if (result != ISC_R_SUCCESS) {
1261                 xfrin_log(xfr, ISC_LOG_DEBUG(3), "TSIG check failed: %s",
1262                        isc_result_totext(result));
1263                 goto failure;
1264         }
1265
1266         for (result = dns_message_firstname(msg, DNS_SECTION_ANSWER);
1267              result == ISC_R_SUCCESS;
1268              result = dns_message_nextname(msg, DNS_SECTION_ANSWER))
1269         {
1270                 dns_rdataset_t *rds;
1271
1272                 name = NULL;
1273                 dns_message_currentname(msg, DNS_SECTION_ANSWER, &name);
1274                 for (rds = ISC_LIST_HEAD(name->list);
1275                      rds != NULL;
1276                      rds = ISC_LIST_NEXT(rds, link))
1277                 {
1278                         for (result = dns_rdataset_first(rds);
1279                              result == ISC_R_SUCCESS;
1280                              result = dns_rdataset_next(rds))
1281                         {
1282                                 dns_rdata_t rdata = DNS_RDATA_INIT;
1283                                 dns_rdataset_current(rds, &rdata);
1284                                 CHECK(xfr_rr(xfr, name, rds->ttl, &rdata));
1285                         }
1286                 }
1287         }
1288         if (result != ISC_R_NOMORE)
1289                 goto failure;
1290
1291         if (dns_message_gettsig(msg, &tsigowner) != NULL) {
1292                 /*
1293                  * Reset the counter.
1294                  */
1295                 xfr->sincetsig = 0;
1296
1297                 /*
1298                  * Free the last tsig, if there is one.
1299                  */
1300                 if (xfr->lasttsig != NULL)
1301                         isc_buffer_free(&xfr->lasttsig);
1302
1303                 /*
1304                  * Update the last tsig pointer.
1305                  */
1306                 CHECK(dns_message_getquerytsig(msg, xfr->mctx,
1307                                                &xfr->lasttsig));
1308
1309         } else if (dns_message_gettsigkey(msg) != NULL) {
1310                 xfr->sincetsig++;
1311                 if (xfr->sincetsig > 100 || xfr->nmsg == 0 ||
1312                     xfr->state == XFRST_AXFR_END ||
1313                     xfr->state == XFRST_IXFR_END)
1314                 {
1315                         result = DNS_R_EXPECTEDTSIG;
1316                         goto failure;
1317                 }
1318         }
1319
1320         /*
1321          * Update the number of messages received.
1322          */
1323         xfr->nmsg++;
1324
1325         /*
1326          * Update the number of bytes received.
1327          */
1328         xfr->nbytes += tcpmsg->buffer.used;
1329
1330         /*
1331          * Take the context back.
1332          */
1333         INSIST(xfr->tsigctx == NULL);
1334         xfr->tsigctx = msg->tsigctx;
1335         msg->tsigctx = NULL;
1336
1337         dns_message_destroy(&msg);
1338
1339         switch (xfr->state) {
1340         case XFRST_GOTSOA:
1341                 xfr->reqtype = dns_rdatatype_axfr;
1342                 xfr->state = XFRST_INITIALSOA;
1343                 CHECK(xfrin_send_request(xfr));
1344                 break;
1345         case XFRST_AXFR_END:
1346                 CHECK(axfr_finalize(xfr));
1347                 /* FALLTHROUGH */
1348         case XFRST_IXFR_END:
1349                 /*
1350                  * Close the journal.
1351                  */
1352                 if (xfr->ixfr.journal != NULL)
1353                         dns_journal_destroy(&xfr->ixfr.journal);
1354
1355                 /*
1356                  * Inform the caller we succeeded.
1357                  */
1358                 if (xfr->done != NULL) {
1359                         (xfr->done)(xfr->zone, ISC_R_SUCCESS);
1360                         xfr->done = NULL;
1361                 }
1362                 /*
1363                  * We should have no outstanding events at this
1364                  * point, thus maybe_free() should succeed.
1365                  */
1366                 xfr->shuttingdown = ISC_TRUE;
1367                 maybe_free(xfr);
1368                 break;
1369         default:
1370                 /*
1371                  * Read the next message.
1372                  */
1373                 CHECK(dns_tcpmsg_readmessage(&xfr->tcpmsg, xfr->task,
1374                                              xfrin_recv_done, xfr));
1375                 xfr->recvs++;
1376         }
1377         return;
1378
1379  failure:
1380         if (msg != NULL)
1381                 dns_message_destroy(&msg);
1382         if (result != ISC_R_SUCCESS)
1383                 xfrin_fail(xfr, result, "failed while receiving responses");
1384 }
1385
1386 static void
1387 xfrin_timeout(isc_task_t *task, isc_event_t *event) {
1388         dns_xfrin_ctx_t *xfr = (dns_xfrin_ctx_t *) event->ev_arg;
1389
1390         REQUIRE(VALID_XFRIN(xfr));
1391
1392         UNUSED(task);
1393
1394         isc_event_free(&event);
1395         /*
1396          * This will log "giving up: timeout".
1397          */
1398         xfrin_fail(xfr, ISC_R_TIMEDOUT, "giving up");
1399 }
1400
1401 static void
1402 maybe_free(dns_xfrin_ctx_t *xfr) {
1403         isc_uint64_t msecs;
1404         isc_uint64_t persec;
1405
1406         REQUIRE(VALID_XFRIN(xfr));
1407
1408         if (! xfr->shuttingdown || xfr->refcount != 0 ||
1409             xfr->connects != 0 || xfr->sends != 0 ||
1410             xfr->recvs != 0)
1411                 return;
1412
1413         /*
1414          * Calculate the length of time the transfer took,
1415          * and print a log message with the bytes and rate.
1416          */
1417         isc_time_now(&xfr->end);
1418         msecs = isc_time_microdiff(&xfr->end, &xfr->start) / 1000;
1419         if (msecs == 0)
1420                 msecs = 1;
1421         persec = (xfr->nbytes * 1000) / msecs;
1422         xfrin_log(xfr, ISC_LOG_INFO,
1423                   "Transfer completed: %d messages, %d records, "
1424                   "%" ISC_PRINT_QUADFORMAT "u bytes, "
1425                   "%u.%03u secs (%u bytes/sec)",
1426                   xfr->nmsg, xfr->nrecs, xfr->nbytes,
1427                   (unsigned int) (msecs / 1000), (unsigned int) (msecs % 1000),
1428                   (unsigned int) persec);
1429
1430         if (xfr->socket != NULL)
1431                 isc_socket_detach(&xfr->socket);
1432
1433         if (xfr->timer != NULL)
1434                 isc_timer_detach(&xfr->timer);
1435
1436         if (xfr->task != NULL)
1437                 isc_task_detach(&xfr->task);
1438
1439         if (xfr->tsigkey != NULL)
1440                 dns_tsigkey_detach(&xfr->tsigkey);
1441
1442         if (xfr->lasttsig != NULL)
1443                 isc_buffer_free(&xfr->lasttsig);
1444
1445         dns_diff_clear(&xfr->diff);
1446
1447         if (xfr->ixfr.journal != NULL)
1448                 dns_journal_destroy(&xfr->ixfr.journal);
1449
1450         if (xfr->axfr.add_private != NULL)
1451                 (void)dns_db_endload(xfr->db, &xfr->axfr.add_private);
1452
1453         if (xfr->tcpmsg_valid)
1454                 dns_tcpmsg_invalidate(&xfr->tcpmsg);
1455
1456         if (xfr->tsigctx != NULL)
1457                 dst_context_destroy(&xfr->tsigctx);
1458
1459         if ((xfr->name.attributes & DNS_NAMEATTR_DYNAMIC) != 0)
1460                 dns_name_free(&xfr->name, xfr->mctx);
1461
1462         if (xfr->ver != NULL)
1463                 dns_db_closeversion(xfr->db, &xfr->ver, ISC_FALSE);
1464
1465         if (xfr->db != NULL)
1466                 dns_db_detach(&xfr->db);
1467
1468         if (xfr->zone != NULL)
1469                 dns_zone_idetach(&xfr->zone);
1470
1471         isc_mem_putanddetach(&xfr->mctx, xfr, sizeof(*xfr));
1472 }
1473
1474 /*
1475  * Log incoming zone transfer messages in a format like
1476  * transfer of <zone> from <address>: <message>
1477  */
1478 static void
1479 xfrin_logv(int level, const char *zonetext, isc_sockaddr_t *masteraddr,
1480            const char *fmt, va_list ap)
1481 {
1482         char mastertext[ISC_SOCKADDR_FORMATSIZE];
1483         char msgtext[2048];
1484
1485         isc_sockaddr_format(masteraddr, mastertext, sizeof(mastertext));
1486         vsnprintf(msgtext, sizeof(msgtext), fmt, ap);
1487
1488         isc_log_write(dns_lctx, DNS_LOGCATEGORY_XFER_IN,
1489                       DNS_LOGMODULE_XFER_IN, level,
1490                       "transfer of '%s' from %s: %s",
1491                       zonetext, mastertext, msgtext);
1492 }
1493
1494 /*
1495  * Logging function for use when a xfrin_ctx_t has not yet been created.
1496  */
1497
1498 static void
1499 xfrin_log1(int level, const char *zonetext, isc_sockaddr_t *masteraddr,
1500            const char *fmt, ...)
1501 {
1502         va_list ap;
1503
1504         if (isc_log_wouldlog(dns_lctx, level) == ISC_FALSE)
1505                 return;
1506
1507         va_start(ap, fmt);
1508         xfrin_logv(level, zonetext, masteraddr, fmt, ap);
1509         va_end(ap);
1510 }
1511
1512 /*
1513  * Logging function for use when there is a xfrin_ctx_t.
1514  */
1515
1516 static void
1517 xfrin_log(dns_xfrin_ctx_t *xfr, int level, const char *fmt, ...)
1518 {
1519         va_list ap;
1520         char zonetext[DNS_NAME_MAXTEXT+32];
1521
1522         if (isc_log_wouldlog(dns_lctx, level) == ISC_FALSE)
1523                 return;
1524
1525         dns_zone_name(xfr->zone, zonetext, sizeof(zonetext));
1526
1527         va_start(ap, fmt);
1528         xfrin_logv(level, zonetext, &xfr->masteraddr, fmt, ap);
1529         va_end(ap);
1530 }