source/wrepl_server/wrepl_scavenging.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    WINS Replication server
   5
   6    Copyright (C) Stefan Metzmacher      2005
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22 #include "includes.h"
  23 #include "librpc/gen_ndr/ndr_winsrepl.h"
  24 #include "wrepl_server/wrepl_server.h"
  25 #include "nbt_server/wins/winsdb.h"
  26 #include "ldb/include/ldb.h"
  27 #include "ldb/include/ldb_errors.h"
  28 #include "system/time.h"
  29 #include "smbd/service_task.h"
  30 #include "lib/messaging/irpc.h"
  31 #include "librpc/gen_ndr/ndr_irpc.h"
  32 #include "librpc/gen_ndr/ndr_nbt.h"
  33
  34 const char *wreplsrv_owner_filter(struct wreplsrv_service *service,
  35                                   TALLOC_CTX *mem_ctx,
  36                                   const char *wins_owner)
  37 {
  38         if (strcmp(wins_owner, service->wins_db->local_owner) == 0) {
  39                 return talloc_asprintf(mem_ctx, "(|(winsOwner=%s)(winsOwner=0.0.0.0))",
  40                                        wins_owner);
  41         }
  42
  43         return talloc_asprintf(mem_ctx, "(&(winsOwner=%s)(!(winsOwner=0.0.0.0)))",
  44                                wins_owner);
  45 }
  46
  47 static NTSTATUS wreplsrv_scavenging_owned_records(struct wreplsrv_service *service, TALLOC_CTX *tmp_mem)
  48 {
  49         NTSTATUS status;
  50         struct winsdb_record *rec = NULL;
  51         struct ldb_result *res = NULL;
  52         const char *owner_filter;
  53         const char *filter;
  54         uint32_t i;
  55         int ret;
  56         time_t now = time(NULL);
  57         const char *now_timestr;
  58         const char *action;
  59         const char *old_state=NULL;
  60         const char *new_state=NULL;
  61         uint32_t modify_flags;
  62         BOOL modify_record;
  63         BOOL delete_record;
  64         BOOL delete_tombstones;
  65         struct timeval tombstone_extra_time;
  66
  67         now_timestr = ldb_timestring(tmp_mem, now);
  68         NT_STATUS_HAVE_NO_MEMORY(now_timestr);
  69         owner_filter = wreplsrv_owner_filter(service, tmp_mem,
  70                                              service->wins_db->local_owner);
  71         NT_STATUS_HAVE_NO_MEMORY(owner_filter);
  72         filter = talloc_asprintf(tmp_mem,
  73                                  "(&%s(objectClass=winsRecord)"
  74                                  "(expireTime<=%s))",
  75                                  owner_filter, now_timestr);
  76         NT_STATUS_HAVE_NO_MEMORY(filter);
  77         ret = ldb_search(service->wins_db->ldb, NULL, LDB_SCOPE_SUBTREE, filter, NULL, &res);
  78         if (ret != LDB_SUCCESS) return NT_STATUS_INTERNAL_DB_CORRUPTION;
  79         talloc_steal(tmp_mem, res);
  80         DEBUG(10,("WINS scavenging: filter '%s' count %d\n", filter, res->count));
  81
  82         tombstone_extra_time = timeval_add(&service->startup_time,
  83                                            service->config.tombstone_extra_timeout,
  84                                            0);
  85         delete_tombstones = timeval_expired(&tombstone_extra_time);
  86
  87         for (i=0; i < res->count; i++) {
  88                 /*
  89                  * we pass '0' as 'now' here,
  90                  * because we want to get the raw timestamps which are in the DB
  91                  */
  92                 status = winsdb_record(service->wins_db, res->msgs[i], tmp_mem, 0, &rec);
  93                 NT_STATUS_NOT_OK_RETURN(status);
  94                 talloc_free(res->msgs[i]);
  95
  96                 modify_flags    = 0;
  97                 modify_record   = False;
  98                 delete_record   = False;
  99
 100                 switch (rec->state) {
 101                 case WREPL_STATE_ACTIVE:
 102                         old_state       = "active";
 103                         new_state       = "active";
 104                         if (!rec->is_static) {
 105                                 new_state       = "released";
 106                                 rec->state      = WREPL_STATE_RELEASED;
 107                                 rec->expire_time= service->config.tombstone_interval + now;
 108                         }
 109                         modify_flags    = 0;
 110                         modify_record   = True;
 111                         break;
 112
 113                 case WREPL_STATE_RELEASED:
 114                         old_state       = "released";
 115                         new_state       = "tombstone";
 116                         rec->state      = WREPL_STATE_TOMBSTONE;
 117                         rec->expire_time= service->config.tombstone_timeout + now;
 118                         modify_flags    = WINSDB_FLAG_ALLOC_VERSION | WINSDB_FLAG_TAKE_OWNERSHIP;
 119                         modify_record   = True;
 120                         break;
 121
 122                 case WREPL_STATE_TOMBSTONE:
 123                         old_state       = "tombstone";
 124                         new_state       = "tombstone";
 125                         if (!delete_tombstones) break;
 126                         new_state       = "deleted";
 127                         delete_record = True;
 128                         break;
 129
 130                 case WREPL_STATE_RESERVED:
 131                         DEBUG(0,("%s: corrupted record: %s\n",
 132                                 __location__, nbt_name_string(rec, rec->name)));
 133                         return NT_STATUS_INTERNAL_DB_CORRUPTION;
 134                 }
 135
 136                 if (modify_record) {
 137                         action = "modify";
 138                         ret = winsdb_modify(service->wins_db, rec, modify_flags);
 139                 } else if (delete_record) {
 140                         action = "delete";
 141                         ret = winsdb_delete(service->wins_db, rec);
 142                 } else {
 143                         action = "skip";
 144                         ret = NBT_RCODE_OK;
 145                 }
 146
 147                 if (ret != NBT_RCODE_OK) {
 148                         DEBUG(1,("WINS scavenging: failed to %s name %s (owned:%s -> owned:%s): error:%u\n",
 149                                 action, nbt_name_string(rec, rec->name), old_state, new_state, ret));
 150                 } else {
 151                         DEBUG(4,("WINS scavenging: %s name: %s (owned:%s -> owned:%s)\n",
 152                                 action, nbt_name_string(rec, rec->name), old_state, new_state));
 153                 }
 154
 155                 talloc_free(rec);
 156         }
 157
 158         return NT_STATUS_OK;
 159 }
 160
 161 static NTSTATUS wreplsrv_scavenging_replica_non_active_records(struct wreplsrv_service *service, TALLOC_CTX *tmp_mem)
 162 {
 163         NTSTATUS status;
 164         struct winsdb_record *rec = NULL;
 165         struct ldb_result *res = NULL;
 166         const char *owner_filter;
 167         const char *filter;
 168         uint32_t i;
 169         int ret;
 170         time_t now = time(NULL);
 171         const char *now_timestr;
 172         const char *action;
 173         const char *old_state=NULL;
 174         const char *new_state=NULL;
 175         uint32_t modify_flags;
 176         BOOL modify_record;
 177         BOOL delete_record;
 178         BOOL delete_tombstones;
 179         struct timeval tombstone_extra_time;
 180
 181         now_timestr = ldb_timestring(tmp_mem, now);
 182         NT_STATUS_HAVE_NO_MEMORY(now_timestr);
 183         owner_filter = wreplsrv_owner_filter(service, tmp_mem,
 184                                              service->wins_db->local_owner);
 185         NT_STATUS_HAVE_NO_MEMORY(owner_filter);
 186         filter = talloc_asprintf(tmp_mem,
 187                                  "(&(!%s)(objectClass=winsRecord)"
 188                                  "(!(recordState=%u))(expireTime<=%s))",
 189                                  owner_filter, WREPL_STATE_ACTIVE, now_timestr);
 190         NT_STATUS_HAVE_NO_MEMORY(filter);
 191         ret = ldb_search(service->wins_db->ldb, NULL, LDB_SCOPE_SUBTREE, filter, NULL, &res);
 192         if (ret != LDB_SUCCESS) return NT_STATUS_INTERNAL_DB_CORRUPTION;
 193         talloc_steal(tmp_mem, res);
 194         DEBUG(10,("WINS scavenging: filter '%s' count %d\n", filter, res->count));
 195
 196         tombstone_extra_time = timeval_add(&service->startup_time,
 197                                            service->config.tombstone_extra_timeout,
 198                                            0);
 199         delete_tombstones = timeval_expired(&tombstone_extra_time);
 200
 201         for (i=0; i < res->count; i++) {
 202                 /*
 203                  * we pass '0' as 'now' here,
 204                  * because we want to get the raw timestamps which are in the DB
 205                  */
 206                 status = winsdb_record(service->wins_db, res->msgs[i], tmp_mem, 0, &rec);
 207                 NT_STATUS_NOT_OK_RETURN(status);
 208                 talloc_free(res->msgs[i]);
 209
 210                 modify_flags    = 0;
 211                 modify_record   = False;
 212                 delete_record   = False;
 213
 214                 switch (rec->state) {
 215                 case WREPL_STATE_ACTIVE:
 216                         DEBUG(0,("%s: corrupted record: %s\n",
 217                                 __location__, nbt_name_string(rec, rec->name)));
 218                         return NT_STATUS_INTERNAL_DB_CORRUPTION;
 219
 220                 case WREPL_STATE_RELEASED:
 221                         old_state       = "released";
 222                         new_state       = "tombstone";
 223                         rec->state      = WREPL_STATE_TOMBSTONE;
 224                         rec->expire_time= service->config.tombstone_timeout + now;
 225                         modify_flags    = 0;
 226                         modify_record   = True;
 227                         break;
 228
 229                 case WREPL_STATE_TOMBSTONE:
 230                         old_state       = "tombstone";
 231                         new_state       = "tombstone";
 232                         if (!delete_tombstones) break;
 233                         new_state       = "deleted";
 234                         delete_record = True;
 235                         break;
 236
 237                 case WREPL_STATE_RESERVED:
 238                         DEBUG(0,("%s: corrupted record: %s\n",
 239                                 __location__, nbt_name_string(rec, rec->name)));
 240                         return NT_STATUS_INTERNAL_DB_CORRUPTION;
 241                 }
 242
 243                 if (modify_record) {
 244                         action = "modify";
 245                         ret = winsdb_modify(service->wins_db, rec, modify_flags);
 246                 } else if (delete_record) {
 247                         action = "delete";
 248                         ret = winsdb_delete(service->wins_db, rec);
 249                 } else {
 250                         action = "skip";
 251                         ret = NBT_RCODE_OK;
 252                 }
 253
 254                 if (ret != NBT_RCODE_OK) {
 255                         DEBUG(1,("WINS scavenging: failed to %s name %s (replica:%s -> replica:%s): error:%u\n",
 256                                 action, nbt_name_string(rec, rec->name), old_state, new_state, ret));
 257                 } else {
 258                         DEBUG(4,("WINS scavenging: %s name: %s (replica:%s -> replica:%s)\n",
 259                                 action, nbt_name_string(rec, rec->name), old_state, new_state));
 260                 }
 261
 262                 talloc_free(rec);
 263         }
 264
 265         return NT_STATUS_OK;
 266 }
 267
 268 struct verify_state {
 269         struct messaging_context *msg_ctx;
 270         struct wreplsrv_service *service;
 271         struct winsdb_record *rec;
 272         struct nbtd_proxy_wins_challenge r;
 273 };
 274
 275 static void verify_handler(struct irpc_request *ireq)
 276 {
 277         struct verify_state *s = talloc_get_type(ireq->async.private,
 278                                  struct verify_state);
 279         struct winsdb_record *rec = s->rec;
 280         const char *action;
 281         const char *old_state = "active";
 282         const char *new_state = "active";
 283         const char *new_owner = "replica";
 284         uint32_t modify_flags = 0;
 285         BOOL modify_record = False;
 286         BOOL delete_record = False;
 287         BOOL different = False;
 288         int ret;
 289         NTSTATUS status;
 290         uint32_t i, j;
 291
 292         /*
 293          * - if the name isn't present anymore remove our record
 294          * - if the name is found and not a normal group check if the addresses match,
 295          *   - if they don't match remove the record
 296          *   - if they match do nothing
 297          * - if an error happens do nothing
 298          */
 299         status = irpc_call_recv(ireq);
 300         if (NT_STATUS_EQUAL(NT_STATUS_OBJECT_NAME_NOT_FOUND, status)) {
 301                 delete_record = True;
 302                 new_state = "deleted";
 303         } else if (NT_STATUS_IS_OK(status) && rec->type != WREPL_TYPE_GROUP) {
 304                 for (i=0; i < s->r.out.num_addrs; i++) {
 305                         BOOL found = False;
 306                         for (j=0; rec->addresses[j]; j++) {
 307                                 if (strcmp(s->r.out.addrs[i].addr, rec->addresses[j]->address) == 0) {
 308                                         found = True;
 309                                         break;
 310                                 }
 311                         }
 312                         if (!found) {
 313                                 different = True;
 314                                 break;
 315                         }
 316                 }
 317         } else if (NT_STATUS_IS_OK(status) && rec->type == WREPL_TYPE_GROUP) {
 318                 if (s->r.out.num_addrs != 1 || strcmp(s->r.out.addrs[0].addr, "255.255.255.255") != 0) {
 319                         different = True;
 320                 }
 321         }
 322
 323         if (different) {
 324                 /*
 325                  * if the reply from the owning wins server has different addresses
 326                  * then take the ownership of the record and make it a tombstone
 327                  * this will then hopefully replicated to the original owner of the record
 328                  * which will then propagate it's own record, so that the current record will
 329                  * be replicated to to us
 330                  */
 331                 DEBUG(0,("WINS scavenging: replica %s verify got different addresses from winsserver: %s: tombstoning record\n",
 332                         nbt_name_string(rec, rec->name), rec->wins_owner));
 333
 334                 rec->state      = WREPL_STATE_TOMBSTONE;
 335                 rec->expire_time= time(NULL) + s->service->config.tombstone_timeout;
 336                 for (i=0; rec->addresses[i]; i++) {
 337                         rec->addresses[i]->expire_time = rec->expire_time;
 338                 }
 339                 modify_record   = True;
 340                 modify_flags    = WINSDB_FLAG_ALLOC_VERSION | WINSDB_FLAG_TAKE_OWNERSHIP;
 341                 new_state       = "tombstone";
 342                 new_owner       = "owned";
 343         } else if (NT_STATUS_IS_OK(status)) {
 344                 /* if the addresses are the same, just update the timestamps */
 345                 rec->expire_time = time(NULL) + s->service->config.verify_interval;
 346                 for (i=0; rec->addresses[i]; i++) {
 347                         rec->addresses[i]->expire_time = rec->expire_time;
 348                 }
 349                 modify_record   = True;
 350                 modify_flags    = 0;
 351                 new_state       = "active";
 352         }
 353
 354         if (modify_record) {
 355                 action = "modify";
 356                 ret = winsdb_modify(s->service->wins_db, rec, modify_flags);
 357         } else if (delete_record) {
 358                 action = "delete";
 359                 ret = winsdb_delete(s->service->wins_db, rec);
 360         } else {
 361                 action = "skip";
 362                 ret = NBT_RCODE_OK;
 363         }
 364
 365         if (ret != NBT_RCODE_OK) {
 366                 DEBUG(1,("WINS scavenging: failed to %s name %s (replica:%s -> %s:%s): error:%u\n",
 367                         action, nbt_name_string(rec, rec->name), old_state, new_owner, new_state, ret));
 368         } else {
 369                 DEBUG(4,("WINS scavenging: %s name: %s (replica:%s -> %s:%s): %s: %s\n",
 370                         action, nbt_name_string(rec, rec->name), old_state, new_owner, new_state,
 371                         rec->wins_owner, nt_errstr(status)));
 372         }
 373
 374         talloc_free(s);
 375 }
 376
 377 static NTSTATUS wreplsrv_scavenging_replica_active_records(struct wreplsrv_service *service, TALLOC_CTX *tmp_mem)
 378 {
 379         NTSTATUS status;
 380         struct winsdb_record *rec = NULL;
 381         struct ldb_result *res = NULL;
 382         const char *owner_filter;
 383         const char *filter;
 384         uint32_t i;
 385         int ret;
 386         time_t now = time(NULL);
 387         const char *now_timestr;
 388         struct irpc_request *ireq;
 389         struct verify_state *s;
 390         struct server_id *nbt_servers;
 391
 392         nbt_servers = irpc_servers_byname(service->task->msg_ctx, tmp_mem, "nbt_server");
 393         if ((nbt_servers == NULL) || (nbt_servers[0].id == 0)) {
 394                 return NT_STATUS_INTERNAL_ERROR;
 395         }
 396
 397         now_timestr = ldb_timestring(tmp_mem, now);
 398         NT_STATUS_HAVE_NO_MEMORY(now_timestr);
 399         owner_filter = wreplsrv_owner_filter(service, tmp_mem,
 400                                              service->wins_db->local_owner);
 401         NT_STATUS_HAVE_NO_MEMORY(owner_filter);
 402         filter = talloc_asprintf(tmp_mem,
 403                                  "(&(!%s)(objectClass=winsRecord)"
 404                                  "(recordState=%u)(expireTime<=%s))",
 405                                  owner_filter, WREPL_STATE_ACTIVE, now_timestr);
 406         NT_STATUS_HAVE_NO_MEMORY(filter);
 407         ret = ldb_search(service->wins_db->ldb, NULL, LDB_SCOPE_SUBTREE, filter, NULL, &res);
 408         if (ret != LDB_SUCCESS) return NT_STATUS_INTERNAL_DB_CORRUPTION;
 409         talloc_steal(tmp_mem, res);
 410         DEBUG(10,("WINS scavenging: filter '%s' count %d\n", filter, res->count));
 411
 412         for (i=0; i < res->count; i++) {
 413                 /*
 414                  * we pass '0' as 'now' here,
 415                  * because we want to get the raw timestamps which are in the DB
 416                  */
 417                 status = winsdb_record(service->wins_db, res->msgs[i], tmp_mem, 0, &rec);
 418                 NT_STATUS_NOT_OK_RETURN(status);
 419                 talloc_free(res->msgs[i]);
 420
 421                 if (rec->state != WREPL_STATE_ACTIVE) {
 422                         DEBUG(0,("%s: corrupted record: %s\n",
 423                                 __location__, nbt_name_string(rec, rec->name)));
 424                         return NT_STATUS_INTERNAL_DB_CORRUPTION;
 425                 }
 426
 427                 /*
 428                  * ask the owning wins server if the record still exists,
 429                  * if not delete the record
 430                  *
 431                  * TODO: NOTE: this is a simpliefied version, to verify that
 432                  *             a record still exist, I assume that w2k3 uses
 433                  *             DCERPC calls or some WINSREPL packets for this,
 434                  *             but we use a wins name query
 435                  */
 436                 DEBUG(0,("ask wins server '%s' if '%s' with version_id:%llu still exists\n",
 437                          rec->wins_owner, nbt_name_string(rec, rec->name),
 438                          (unsigned long long)rec->version));
 439
 440                 s = talloc_zero(tmp_mem, struct verify_state);
 441                 NT_STATUS_HAVE_NO_MEMORY(s);
 442                 s->msg_ctx      = service->task->msg_ctx;
 443                 s->service      = service;
 444                 s->rec          = talloc_steal(s, rec);
 445
 446                 s->r.in.name            = *rec->name;
 447                 s->r.in.num_addrs       = 1;
 448                 s->r.in.addrs           = talloc_array(s, struct nbtd_proxy_wins_addr, s->r.in.num_addrs);
 449                 NT_STATUS_HAVE_NO_MEMORY(s->r.in.addrs);
 450                 /* TODO: fix pidl to handle inline ipv4address arrays */
 451                 s->r.in.addrs[0].addr   = rec->wins_owner;
 452
 453                 ireq = IRPC_CALL_SEND(s->msg_ctx, nbt_servers[0],
 454                                       irpc, NBTD_PROXY_WINS_CHALLENGE,
 455                                       &s->r, s);
 456                 NT_STATUS_HAVE_NO_MEMORY(ireq);
 457
 458                 ireq->async.fn          = verify_handler;
 459                 ireq->async.private     = s;
 460
 461                 talloc_steal(service, s);
 462         }
 463
 464         return NT_STATUS_OK;
 465 }
 466
 467 NTSTATUS wreplsrv_scavenging_run(struct wreplsrv_service *service)
 468 {
 469         NTSTATUS status;
 470         TALLOC_CTX *tmp_mem;
 471         BOOL skip_first_run = False;
 472
 473         if (!timeval_expired(&service->scavenging.next_run)) {
 474                 return NT_STATUS_OK;
 475         }
 476
 477         if (timeval_is_zero(&service->scavenging.next_run)) {
 478                 skip_first_run = True;
 479         }
 480
 481         service->scavenging.next_run = timeval_current_ofs(service->config.scavenging_interval, 0);
 482         status = wreplsrv_periodic_schedule(service, service->config.scavenging_interval);
 483         NT_STATUS_NOT_OK_RETURN(status);
 484
 485         /*
 486          * if it's the first time this functions is called (startup)
 487          * the next_run is zero, in this case we should not do scavenging
 488          */
 489         if (skip_first_run) {
 490                 return NT_STATUS_OK;
 491         }
 492
 493         if (service->scavenging.processing) {
 494                 return NT_STATUS_OK;
 495         }
 496
 497         DEBUG(4,("wreplsrv_scavenging_run(): start\n"));
 498
 499         tmp_mem = talloc_new(service);
 500         NT_STATUS_HAVE_NO_MEMORY(tmp_mem);
 501         service->scavenging.processing = True;
 502         status = wreplsrv_scavenging_owned_records(service,tmp_mem);
 503         service->scavenging.processing = False;
 504         talloc_free(tmp_mem);
 505         NT_STATUS_NOT_OK_RETURN(status);
 506
 507         tmp_mem = talloc_new(service);
 508         NT_STATUS_HAVE_NO_MEMORY(tmp_mem);
 509         service->scavenging.processing = True;
 510         status = wreplsrv_scavenging_replica_non_active_records(service, tmp_mem);
 511         service->scavenging.processing = False;
 512         talloc_free(tmp_mem);
 513         NT_STATUS_NOT_OK_RETURN(status);
 514
 515         tmp_mem = talloc_new(service);
 516         NT_STATUS_HAVE_NO_MEMORY(tmp_mem);
 517         service->scavenging.processing = True;
 518         status = wreplsrv_scavenging_replica_active_records(service, tmp_mem);
 519         service->scavenging.processing = False;
 520         talloc_free(tmp_mem);
 521         NT_STATUS_NOT_OK_RETURN(status);
 522
 523         DEBUG(4,("wreplsrv_scavenging_run(): end\n"));
 524
 525         return NT_STATUS_OK;
 526 }