source4/wrepl_server/wrepl_server.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 2 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, write to the Free Software
  20    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21 */
  22
  23 #include "includes.h"
  24 #include "dlinklist.h"
  25 #include "lib/events/events.h"
  26 #include "lib/socket/socket.h"
  27 #include "smbd/service_task.h"
  28 #include "smbd/service_stream.h"
  29 #include "lib/messaging/irpc.h"
  30 #include "librpc/gen_ndr/ndr_winsrepl.h"
  31 #include "wrepl_server/wrepl_server.h"
  32 #include "nbt_server/wins/winsdb.h"
  33 #include "ldb/include/ldb.h"
  34
  35 /*
  36   open winsdb
  37 */
  38 static NTSTATUS wreplsrv_open_winsdb(struct wreplsrv_service *service)
  39 {
  40         service->wins_db     = winsdb_connect(service);
  41         if (!service->wins_db) {
  42                 return NT_STATUS_INTERNAL_DB_ERROR;
  43         }
  44
  45         return NT_STATUS_OK;
  46 }
  47
  48 struct wreplsrv_partner *wreplsrv_find_partner(struct wreplsrv_service *service, const char *peer_addr)
  49 {
  50         struct wreplsrv_partner *cur;
  51
  52         for (cur = service->partners; cur; cur = cur->next) {
  53                 if (strcmp(cur->address, peer_addr) == 0) {
  54                         return cur;
  55                 }
  56         }
  57
  58         return NULL;
  59 }
  60
  61 /*
  62   load our replication partners
  63 */
  64 static NTSTATUS wreplsrv_load_partners(struct wreplsrv_service *service)
  65 {
  66         struct ldb_message **res = NULL;
  67         int ret;
  68         TALLOC_CTX *tmp_ctx = talloc_new(service);
  69         int i;
  70
  71         /* find the record in the WINS database */
  72         ret = ldb_search(service->wins_db, ldb_dn_explode(tmp_ctx, "CN=PARTNERS"), LDB_SCOPE_ONELEVEL,
  73                          "(objectClass=wreplPartner)", NULL, &res);
  74         if (res != NULL) {
  75                 talloc_steal(tmp_ctx, res);
  76         }
  77         if (ret < 0) goto failed;
  78         if (ret == 0) goto done;
  79
  80         for (i=0; i < ret; i++) {
  81                 struct wreplsrv_partner *partner;
  82
  83                 partner = talloc_zero(service, struct wreplsrv_partner);
  84                 if (partner == NULL) goto failed;
  85                 partner->service        = service;
  86
  87                 partner->address        = ldb_msg_find_string(res[i], "address", NULL);
  88                 if (!partner->address) goto failed;
  89                 partner->name           = ldb_msg_find_string(res[i], "name", partner->address);
  90                 partner->type           = ldb_msg_find_int(res[i], "type", WINSREPL_PARTNER_BOTH);
  91                 partner->pull.interval  = ldb_msg_find_int(res[i], "pullInterval", WINSREPL_DEFAULT_PULL_INTERVAL);
  92                 partner->pull.retry_interval = ldb_msg_find_int(res[i], "pullRetryInterval",
  93                                                                 WINSREPL_DEFAULT_PULL_RETRY_INTERVAL);
  94                 partner->our_address    = ldb_msg_find_string(res[i], "ourAddress", NULL);
  95
  96                 talloc_steal(partner, partner->address);
  97                 talloc_steal(partner, partner->name);
  98                 talloc_steal(partner, partner->our_address);
  99
 100                 DLIST_ADD(service->partners, partner);
 101         }
 102 done:
 103         talloc_free(tmp_ctx);
 104         return NT_STATUS_OK;
 105 failed:
 106         talloc_free(tmp_ctx);
 107         return NT_STATUS_FOOBAR;
 108 }
 109
 110 BOOL wreplsrv_is_our_address(struct wreplsrv_service *service, const char *address)
 111 {
 112         const char *our_address;
 113
 114         if (lp_interfaces() && lp_bind_interfaces_only()) {
 115                 int num_interfaces = iface_count();
 116                 int i;
 117                 for(i = 0; i < num_interfaces; i++) {
 118                         our_address = iface_n_ip(i);
 119                         if (strcasecmp(our_address, address) == 0) {
 120                                 return True;
 121                         }
 122                 }
 123         } else {
 124                 our_address = lp_socket_address();
 125                 if (strcasecmp(our_address, address) == 0) {
 126                         return True;
 127                 }
 128         }
 129
 130         return False;
 131 }
 132
 133 uint64_t wreplsrv_local_max_version(struct wreplsrv_service *service)
 134 {
 135         int ret;
 136         struct ldb_context *ldb = service->wins_db;
 137         struct ldb_dn *dn;
 138         struct ldb_message **res = NULL;
 139         TALLOC_CTX *tmp_ctx = talloc_new(service);
 140         uint64_t maxVersion = 0;
 141
 142         dn = ldb_dn_explode(tmp_ctx, "CN=VERSION");
 143         if (!dn) goto failed;
 144
 145         /* find the record in the WINS database */
 146         ret = ldb_search(ldb, dn, LDB_SCOPE_BASE,
 147                          NULL, NULL, &res);
 148         if (res != NULL) {
 149                 talloc_steal(tmp_ctx, res);
 150         }
 151         if (ret < 0) goto failed;
 152         if (ret > 1) goto failed;
 153
 154         if (ret == 1) {
 155                 maxVersion = ldb_msg_find_uint64(res[0], "maxVersion", 0);
 156         }
 157
 158 failed:
 159         talloc_free(tmp_ctx);
 160         return maxVersion;
 161 }
 162
 163 NTSTATUS wreplsrv_fill_wrepl_table(struct wreplsrv_service *service,
 164                                    TALLOC_CTX *mem_ctx,
 165                                    struct wrepl_table *table_out,
 166                                    const char *our_ip,
 167                                    const char *initiator,
 168                                    BOOL full_table)
 169 {
 170         struct wreplsrv_owner *cur;
 171         uint64_t local_max_version;
 172         uint32_t i = 0;
 173
 174         table_out->partner_count        = 0;
 175         table_out->partners             = NULL;
 176         table_out->initiator            = initiator;
 177
 178         local_max_version = wreplsrv_local_max_version(service);
 179         if (local_max_version > 0) {
 180                 table_out->partner_count++;
 181         }
 182
 183         for (cur = service->table; full_table && cur; cur = cur->next) {
 184                 table_out->partner_count++;
 185         }
 186
 187         table_out->partners = talloc_array(mem_ctx, struct wrepl_wins_owner, table_out->partner_count);
 188         NT_STATUS_HAVE_NO_MEMORY(table_out->partners);
 189
 190         if (local_max_version > 0) {
 191                 table_out->partners[i].address          = our_ip;
 192                 table_out->partners[i].min_version      = 0;
 193                 table_out->partners[i].max_version      = local_max_version;
 194                 table_out->partners[i].type             = 1;
 195                 i++;
 196         }
 197
 198         for (cur = service->table; full_table && cur; cur = cur->next) {
 199                 table_out->partners[i] = cur->owner;
 200                 i++;
 201         }
 202
 203         return NT_STATUS_OK;
 204 }
 205
 206 struct wreplsrv_owner *wreplsrv_find_owner(struct wreplsrv_owner *table, const char *wins_owner)
 207 {
 208         struct wreplsrv_owner *cur;
 209
 210         for (cur = table; cur; cur = cur->next) {
 211                 if (strcmp(cur->owner.address, wins_owner) == 0) {
 212                         return cur;
 213                 }
 214         }
 215
 216         return NULL;
 217 }
 218
 219 /*
 220  update the wins_owner_table max_version, if the given version is the highest version
 221  if no entry for the wins_owner exists yet, create one
 222 */
 223 NTSTATUS wreplsrv_add_table(struct wreplsrv_service *service,
 224                             TALLOC_CTX *mem_ctx, struct wreplsrv_owner **_table,
 225                             const char *wins_owner, uint64_t version)
 226 {
 227         struct wreplsrv_owner *table = *_table;
 228         struct wreplsrv_owner *cur;
 229
 230         if (strcmp(WINSDB_OWNER_LOCAL, wins_owner) == 0) {
 231                 return NT_STATUS_OK;
 232         }
 233
 234         cur = wreplsrv_find_owner(table, wins_owner);
 235
 236         /* if it doesn't exists yet, create one */
 237         if (!cur) {
 238                 cur = talloc_zero(mem_ctx, struct wreplsrv_owner);
 239                 NT_STATUS_HAVE_NO_MEMORY(cur);
 240
 241                 cur->owner.address      = talloc_strdup(cur, wins_owner);
 242                 NT_STATUS_HAVE_NO_MEMORY(cur->owner.address);
 243                 cur->owner.min_version  = 0;
 244                 cur->owner.max_version  = 0;
 245                 cur->owner.type         = 1; /* don't know why this is always 1 */
 246
 247                 cur->partner            = wreplsrv_find_partner(service, wins_owner);
 248
 249                 DLIST_ADD(table, cur);
 250                 *_table = table;
 251         }
 252
 253         /* the min_version is always 0 here, and won't be updated */
 254
 255         /* if the given version is higher the then current nax_version, update */
 256         if (cur->owner.max_version < version) {
 257                 cur->owner.max_version = version;
 258         }
 259
 260         return NT_STATUS_OK;
 261 }
 262
 263 /*
 264   load the partner table
 265 */
 266 static NTSTATUS wreplsrv_load_table(struct wreplsrv_service *service)
 267 {
 268         struct ldb_message **res = NULL;
 269         int ret;
 270         NTSTATUS status;
 271         TALLOC_CTX *tmp_ctx = talloc_new(service);
 272         int i;
 273         const char *wins_owner;
 274         uint64_t version;
 275         const char * const attrs[] = {
 276                 "winsOwner",
 277                 "versionID",
 278                 NULL
 279         };
 280
 281         /* find the record in the WINS database */
 282         ret = ldb_search(service->wins_db, NULL, LDB_SCOPE_SUBTREE,
 283                          "(objectClass=winsRecord)", attrs, &res);
 284         if (res != NULL) {
 285                 talloc_steal(tmp_ctx, res);
 286         }
 287         status = NT_STATUS_INTERNAL_DB_CORRUPTION;
 288         if (ret < 0) goto failed;
 289         if (ret == 0) goto done;
 290
 291         for (i=0; i < ret; i++) {
 292                 wins_owner     = ldb_msg_find_string(res[i], "winsOwner", NULL);
 293                 version        = ldb_msg_find_uint64(res[i], "versionID", 0);
 294
 295                 if (wins_owner) {
 296                         status = wreplsrv_add_table(service,
 297                                                     service, &service->table,
 298                                                     wins_owner, version);
 299                         if (!NT_STATUS_IS_OK(status)) goto failed;
 300                 }
 301                 talloc_free(res[i]);
 302
 303                 /* TODO: what's abut the per address owners? */
 304         }
 305 done:
 306         talloc_free(tmp_ctx);
 307         return NT_STATUS_OK;
 308 failed:
 309         talloc_free(tmp_ctx);
 310         return status;
 311 }
 312
 313 /*
 314   setup our replication partners
 315 */
 316 static NTSTATUS wreplsrv_setup_partners(struct wreplsrv_service *service)
 317 {
 318         NTSTATUS status;
 319
 320         status = wreplsrv_load_partners(service);
 321         NT_STATUS_NOT_OK_RETURN(status);
 322
 323         status = wreplsrv_load_table(service);
 324         NT_STATUS_NOT_OK_RETURN(status);
 325
 326         status = wreplsrv_setup_out_connections(service);
 327         NT_STATUS_NOT_OK_RETURN(status);
 328
 329         return NT_STATUS_OK;
 330 }
 331
 332 /*
 333   startup the wrepl task
 334 */
 335 static void wreplsrv_task_init(struct task_server *task)
 336 {
 337         NTSTATUS status;
 338         struct wreplsrv_service *service;
 339
 340         service = talloc_zero(task, struct wreplsrv_service);
 341         if (!service) {
 342                 task_server_terminate(task, "wreplsrv_task_init: out of memory");
 343                 return;
 344         }
 345         service->task = task;
 346         task->private = service;
 347
 348         /*
 349          * setup up all partners, and open the winsdb
 350          */
 351         status = wreplsrv_open_winsdb(service);
 352         if (!NT_STATUS_IS_OK(status)) {
 353                 task_server_terminate(task, "wreplsrv_task_init: wreplsrv_open_winsdb() failed");
 354                 return;
 355         }
 356
 357         /*
 358          * setup timed events for each partner we want to pull from
 359          */
 360         status = wreplsrv_setup_partners(service);
 361         if (!NT_STATUS_IS_OK(status)) {
 362                 task_server_terminate(task, "wreplsrv_task_init: wreplsrv_setup_partners() failed");
 363                 return;
 364         }
 365
 366         /*
 367          * setup listen sockets, so we can anwser requests from our partners,
 368          * which pull from us
 369          */
 370         status = wreplsrv_setup_sockets(service);
 371         if (!NT_STATUS_IS_OK(status)) {
 372                 task_server_terminate(task, "wreplsrv_task_init: wreplsrv_setup_sockets() failed");
 373                 return;
 374         }
 375
 376         irpc_add_name(task->msg_ctx, "wrepl_server");
 377 }
 378
 379 /*
 380   initialise the WREPL server
 381  */
 382 static NTSTATUS wreplsrv_init(struct event_context *event_ctx, const struct model_ops *model_ops)
 383 {
 384         if (!lp_wins_support()) {
 385                 return NT_STATUS_OK;
 386         }
 387
 388         return task_server_startup(event_ctx, model_ops, wreplsrv_task_init);
 389 }
 390
 391 /*
 392   register ourselves as a available server
 393 */
 394 NTSTATUS server_service_wrepl_init(void)
 395 {
 396         return register_server_service("wrepl", wreplsrv_init);
 397 }