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