source4/dsdb/repl/drepl_ridalloc.c

   1 /*
   2    Unix SMB/CIFS mplementation.
   3
   4    DSDB replication service - RID allocation code
   5
   6    Copyright (C) Andrew Tridgell 2010
   7    Copyright (C) Andrew Bartlett 2010
   8
   9    based on drepl_notify.c
  10
  11    This program is free software; you can redistribute it and/or modify
  12    it under the terms of the GNU General Public License as published by
  13    the Free Software Foundation; either version 3 of the License, or
  14    (at your option) any later version.
  15
  16    This program is distributed in the hope that it will be useful,
  17    but WITHOUT ANY WARRANTY; without even the implied warranty of
  18    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19    GNU General Public License for more details.
  20
  21    You should have received a copy of the GNU General Public License
  22    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  23
  24 */
  25
  26 #include "includes.h"
  27 #include "ldb_module.h"
  28 #include "dsdb/samdb/samdb.h"
  29 #include "smbd/service.h"
  30 #include "dsdb/repl/drepl_service.h"
  31 #include "param/param.h"
  32
  33
  34 /*
  35   create the role owner source dsa structure
  36  */
  37
  38 WERROR drepl_create_role_owner_source_dsa(struct dreplsrv_service *service,
  39                                           struct ldb_dn *role_owner_dn, struct ldb_dn *fsmo_role_dn)
  40 {
  41         struct dreplsrv_partition_source_dsa *sdsa;
  42         struct ldb_context *ldb = service->samdb;
  43         int ret;
  44         WERROR werr;
  45
  46         sdsa = talloc_zero(service, struct dreplsrv_partition_source_dsa);
  47         W_ERROR_HAVE_NO_MEMORY(sdsa);
  48
  49         sdsa->partition = talloc_zero(sdsa, struct dreplsrv_partition);
  50         if (!sdsa->partition) {
  51                 talloc_free(sdsa);
  52                 return WERR_NOMEM;
  53         }
  54
  55         sdsa->partition->dn = ldb_dn_copy(sdsa->partition, role_owner_dn);
  56         if (!sdsa->partition->dn) {
  57                 talloc_free(sdsa);
  58                 return WERR_NOMEM;
  59         }
  60         sdsa->partition->nc.dn = ldb_dn_alloc_linearized(sdsa->partition, role_owner_dn);
  61         if (!sdsa->partition->nc.dn) {
  62                 talloc_free(sdsa);
  63                 return WERR_NOMEM;
  64         }
  65         ret = dsdb_find_guid_by_dn(ldb, role_owner_dn, &sdsa->partition->nc.guid);
  66         if (ret != LDB_SUCCESS) {
  67                 DEBUG(0,(__location__ ": Failed to find GUID for %s\n",
  68                          ldb_dn_get_linearized(role_owner_dn)));
  69                 talloc_free(sdsa);
  70                 return WERR_DS_DRA_INTERNAL_ERROR;
  71         }
  72
  73         sdsa->repsFrom1 = &sdsa->_repsFromBlob.ctr.ctr1;
  74         ret = dsdb_find_guid_attr_by_dn(ldb, fsmo_role_dn, "objectGUID", &sdsa->repsFrom1->source_dsa_obj_guid);
  75         if (ret != LDB_SUCCESS) {
  76                 DEBUG(0,(__location__ ": Failed to find objectGUID for %s\n",
  77                          ldb_dn_get_linearized(fsmo_role_dn)));
  78                 talloc_free(sdsa);
  79                 return WERR_DS_DRA_INTERNAL_ERROR;
  80         }
  81
  82         sdsa->repsFrom1->other_info = talloc_zero(sdsa, struct repsFromTo1OtherInfo);
  83         if (!sdsa->repsFrom1->other_info) {
  84                 talloc_free(sdsa);
  85                 return WERR_NOMEM;
  86         }
  87
  88         sdsa->repsFrom1->other_info->dns_name =
  89                 talloc_asprintf(sdsa->repsFrom1->other_info, "%s._msdcs.%s",
  90                                 GUID_string(sdsa->repsFrom1->other_info, &sdsa->repsFrom1->source_dsa_obj_guid),
  91                                 lpcfg_dnsdomain(service->task->lp_ctx));
  92         if (!sdsa->repsFrom1->other_info->dns_name) {
  93                 talloc_free(sdsa);
  94                 return WERR_NOMEM;
  95         }
  96
  97
  98         werr = dreplsrv_out_connection_attach(service, sdsa->repsFrom1, &sdsa->conn);
  99         if (!W_ERROR_IS_OK(werr)) {
 100                 DEBUG(0,(__location__ ": Failed to attach connection to %s\n",
 101                          ldb_dn_get_linearized(role_owner_dn)));
 102                 talloc_free(sdsa);
 103                 return werr;
 104         }
 105
 106         service->ncchanges_extended.role_owner_source_dsa = sdsa;
 107         return WERR_OK;
 108 }
 109
 110 /*
 111   schedule a getncchanges request to the role owner for an extended operation
 112  */
 113 WERROR drepl_request_extended_op(struct dreplsrv_service *service,
 114                                  struct ldb_dn *role_owner_dn,
 115                                  struct ldb_dn *fsmo_role_dn,
 116                                  enum drsuapi_DsExtendedOperation extended_op,
 117                                  uint64_t alloc_pool,
 118                                  dreplsrv_fsmo_callback_t callback)
 119 {
 120         WERROR werr;
 121
 122         if (service->ncchanges_extended.role_owner_source_dsa == NULL) {
 123                 /* we need to establish a connection to the RID
 124                    Manager */
 125                 werr = drepl_create_role_owner_source_dsa(service, role_owner_dn, fsmo_role_dn);
 126                 W_ERROR_NOT_OK_RETURN(werr);
 127         }
 128
 129         service->ncchanges_extended.in_progress = true;
 130
 131         werr = dreplsrv_schedule_partition_pull_source(service, service->ncchanges_extended.role_owner_source_dsa,
 132                                                        extended_op, alloc_pool,
 133                                                        callback, NULL);
 134         return werr;
 135 }
 136
 137 /*
 138   called when a rid allocation request has completed
 139  */
 140 static void drepl_new_rid_pool_callback(struct dreplsrv_service *service,
 141                                         WERROR werr,
 142                                         enum drsuapi_DsExtendedError ext_err,
 143                                         void *cb_data)
 144 {
 145         if (!W_ERROR_IS_OK(werr)) {
 146                 DEBUG(0,(__location__ ": RID Manager failed RID allocation - %s - extended_ret[0x%X]\n",
 147                          win_errstr(werr), ext_err));
 148         } else {
 149                 DEBUG(3,(__location__ ": RID Manager completed RID allocation OK\n"));
 150         }
 151
 152         /* don't keep the connection open to the RID Manager */
 153         talloc_free(service->ncchanges_extended.role_owner_source_dsa);
 154         service->ncchanges_extended.role_owner_source_dsa = NULL;
 155
 156         service->ncchanges_extended.in_progress = false;
 157 }
 158
 159 /*
 160   schedule a getncchanges request to the RID Manager to ask for a new
 161   set of RIDs using DRSUAPI_EXOP_FSMO_RID_ALLOC
 162  */
 163 static WERROR drepl_request_new_rid_pool(struct dreplsrv_service *service,
 164                                          struct ldb_dn *rid_manager_dn, struct ldb_dn *fsmo_role_dn,
 165                                          uint64_t alloc_pool)
 166 {
 167         WERROR werr = drepl_request_extended_op(service,
 168                                                 rid_manager_dn,
 169                                                 fsmo_role_dn,
 170                                                 DRSUAPI_EXOP_FSMO_RID_ALLOC,
 171                                                 alloc_pool,
 172                                                 drepl_new_rid_pool_callback);
 173         return werr;
 174 }
 175
 176
 177 /*
 178   see if we are on the last pool we have
 179  */
 180 static int drepl_ridalloc_pool_exhausted(struct ldb_context *ldb,
 181                                          bool *exhausted,
 182                                          uint64_t *_alloc_pool)
 183 {
 184         struct ldb_dn *server_dn, *machine_dn, *rid_set_dn;
 185         TALLOC_CTX *tmp_ctx = talloc_new(ldb);
 186         uint64_t alloc_pool;
 187         uint64_t prev_pool;
 188         uint32_t prev_pool_lo, prev_pool_hi;
 189         uint32_t next_rid;
 190         static const char * const attrs[] = {
 191                 "rIDAllocationPool",
 192                 "rIDPreviousAllocationPool",
 193                 "rIDNextRid",
 194                 NULL
 195         };
 196         int ret;
 197         struct ldb_result *res;
 198
 199         *exhausted = false;
 200         *_alloc_pool = UINT64_MAX;
 201
 202         server_dn = ldb_dn_get_parent(tmp_ctx, samdb_ntds_settings_dn(ldb));
 203         if (!server_dn) {
 204                 talloc_free(tmp_ctx);
 205                 return ldb_operr(ldb);
 206         }
 207
 208         ret = samdb_reference_dn(ldb, tmp_ctx, server_dn, "serverReference", &machine_dn);
 209         if (ret != LDB_SUCCESS) {
 210                 DEBUG(0,(__location__ ": Failed to find serverReference in %s - %s",
 211                          ldb_dn_get_linearized(server_dn), ldb_errstring(ldb)));
 212                 talloc_free(tmp_ctx);
 213                 return ret;
 214         }
 215
 216         ret = samdb_reference_dn(ldb, tmp_ctx, machine_dn, "rIDSetReferences", &rid_set_dn);
 217         if (ret == LDB_ERR_NO_SUCH_ATTRIBUTE) {
 218                 *exhausted = true;
 219                 *_alloc_pool = 0;
 220                 talloc_free(tmp_ctx);
 221                 return LDB_SUCCESS;
 222         }
 223         if (ret != LDB_SUCCESS) {
 224                 DEBUG(0,(__location__ ": Failed to find rIDSetReferences in %s - %s",
 225                          ldb_dn_get_linearized(machine_dn), ldb_errstring(ldb)));
 226                 talloc_free(tmp_ctx);
 227                 return ret;
 228         }
 229
 230         ret = ldb_search(ldb, tmp_ctx, &res, rid_set_dn, LDB_SCOPE_BASE, attrs, NULL);
 231         if (ret != LDB_SUCCESS) {
 232                 DEBUG(0,(__location__ ": Failed to load RID Set attrs from %s - %s",
 233                          ldb_dn_get_linearized(rid_set_dn), ldb_errstring(ldb)));
 234                 talloc_free(tmp_ctx);
 235                 return ret;
 236         }
 237
 238         alloc_pool = ldb_msg_find_attr_as_uint64(res->msgs[0], "rIDAllocationPool", 0);
 239         prev_pool = ldb_msg_find_attr_as_uint64(res->msgs[0], "rIDPreviousAllocationPool", 0);
 240         prev_pool_lo = prev_pool & 0xFFFFFFFF;
 241         prev_pool_hi = prev_pool >> 32;
 242         next_rid = ldb_msg_find_attr_as_uint(res->msgs[0], "rIDNextRid", 0);
 243
 244         if (alloc_pool != prev_pool) {
 245                 talloc_free(tmp_ctx);
 246                 return LDB_SUCCESS;
 247         }
 248
 249         if (next_rid < (prev_pool_hi + prev_pool_lo)/2) {
 250                 talloc_free(tmp_ctx);
 251                 return LDB_SUCCESS;
 252         }
 253
 254         *exhausted = true;
 255         *_alloc_pool = alloc_pool;
 256         talloc_free(tmp_ctx);
 257         return LDB_SUCCESS;
 258 }
 259
 260
 261 /*
 262   see if we are low on RIDs in the RID Set rIDAllocationPool. If we
 263   are, then schedule a replication call with DRSUAPI_EXOP_FSMO_RID_ALLOC
 264   to the RID Manager
 265  */
 266 WERROR dreplsrv_ridalloc_check_rid_pool(struct dreplsrv_service *service)
 267 {
 268         struct ldb_dn *rid_manager_dn, *fsmo_role_dn;
 269         TALLOC_CTX *tmp_ctx = talloc_new(service);
 270         struct ldb_context *ldb = service->samdb;
 271         bool exhausted;
 272         WERROR werr;
 273         int ret;
 274         uint64_t alloc_pool;
 275
 276         if (service->ncchanges_extended.in_progress) {
 277                 talloc_free(tmp_ctx);
 278                 return WERR_OK;
 279         }
 280
 281         /*
 282           steps:
 283             - find who the RID Manager is
 284             - if we are the RID Manager then nothing to do
 285             - find our RID Set object
 286             - load rIDAllocationPool and rIDPreviousAllocationPool
 287             - if rIDAllocationPool != rIDPreviousAllocationPool then
 288               nothing to do
 289             - schedule a getncchanges with DRSUAPI_EXOP_FSMO_RID_ALLOC
 290               to the RID Manager
 291          */
 292
 293         /* work out who is the RID Manager */
 294         ret = samdb_rid_manager_dn(ldb, tmp_ctx, &rid_manager_dn);
 295         if (ret != LDB_SUCCESS) {
 296                 DEBUG(0, (__location__ ": Failed to find RID Manager object - %s", ldb_errstring(ldb)));
 297                 talloc_free(tmp_ctx);
 298                 return WERR_DS_DRA_INTERNAL_ERROR;
 299         }
 300
 301         /* find the DN of the RID Manager */
 302         ret = samdb_reference_dn(ldb, tmp_ctx, rid_manager_dn, "fSMORoleOwner", &fsmo_role_dn);
 303         if (ret != LDB_SUCCESS) {
 304                 DEBUG(0,(__location__ ": Failed to find fSMORoleOwner in RID Manager object - %s",
 305                          ldb_errstring(ldb)));
 306                 talloc_free(tmp_ctx);
 307                 return WERR_DS_DRA_INTERNAL_ERROR;
 308         }
 309
 310         if (ldb_dn_compare(samdb_ntds_settings_dn(ldb), fsmo_role_dn) == 0) {
 311                 /* we are the RID Manager - no need to do a
 312                    DRSUAPI_EXOP_FSMO_RID_ALLOC */
 313                 talloc_free(tmp_ctx);
 314                 return WERR_OK;
 315         }
 316
 317         ret = drepl_ridalloc_pool_exhausted(ldb, &exhausted, &alloc_pool);
 318         if (ret != LDB_SUCCESS) {
 319                 talloc_free(tmp_ctx);
 320                 return WERR_DS_DRA_INTERNAL_ERROR;
 321         }
 322
 323         if (!exhausted) {
 324                 /* don't need a new pool */
 325                 talloc_free(tmp_ctx);
 326                 return WERR_OK;
 327         }
 328
 329         DEBUG(2,(__location__ ": Requesting more RIDs from RID Manager\n"));
 330
 331         werr = drepl_request_new_rid_pool(service, rid_manager_dn, fsmo_role_dn, alloc_pool);
 332         talloc_free(tmp_ctx);
 333         return werr;
 334 }
 335
 336 /* called by the samldb ldb module to tell us to ask for a new RID
 337    pool */
 338 void dreplsrv_allocate_rid(struct messaging_context *msg, void *private_data,
 339                            uint32_t msg_type,
 340                            struct server_id server_id, DATA_BLOB *data)
 341 {
 342         struct dreplsrv_service *service = talloc_get_type(private_data, struct dreplsrv_service);
 343         dreplsrv_ridalloc_check_rid_pool(service);
 344 }