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 "dsdb/samdb/samdb.h"
  28 #include "smbd/service.h"
  29 #include "dsdb/repl/drepl_service.h"
  30 #include "param/param.h"
  31
  32
  33 /*
  34   create the RID manager source dsa structure
  35  */
  36 static WERROR drepl_create_rid_manager_source_dsa(struct dreplsrv_service *service,
  37                                                   struct ldb_dn *rid_manager_dn, struct ldb_dn *fsmo_role_dn)
  38 {
  39         struct dreplsrv_partition_source_dsa *sdsa;
  40         struct ldb_context *ldb = service->samdb;
  41         int ret;
  42         WERROR werr;
  43
  44         sdsa = talloc_zero(service, struct dreplsrv_partition_source_dsa);
  45         W_ERROR_HAVE_NO_MEMORY(sdsa);
  46
  47         sdsa->partition = talloc_zero(sdsa, struct dreplsrv_partition);
  48         if (!sdsa->partition) {
  49                 talloc_free(sdsa);
  50                 return WERR_NOMEM;
  51         }
  52
  53         sdsa->partition->dn = ldb_get_default_basedn(ldb);
  54         sdsa->partition->nc.dn = ldb_dn_alloc_linearized(sdsa->partition, rid_manager_dn);
  55         ret = dsdb_find_guid_by_dn(ldb, rid_manager_dn, &sdsa->partition->nc.guid);
  56         if (ret != LDB_SUCCESS) {
  57                 DEBUG(0,(__location__ ": Failed to find GUID for %s\n",
  58                          ldb_dn_get_linearized(rid_manager_dn)));
  59                 talloc_free(sdsa);
  60                 return WERR_DS_DRA_INTERNAL_ERROR;
  61         }
  62
  63         sdsa->repsFrom1 = &sdsa->_repsFromBlob.ctr.ctr1;
  64         ret = dsdb_find_guid_attr_by_dn(ldb, fsmo_role_dn, "objectGUID", &sdsa->repsFrom1->source_dsa_obj_guid);
  65         if (ret != LDB_SUCCESS) {
  66                 DEBUG(0,(__location__ ": Failed to find objectGUID for %s\n",
  67                          ldb_dn_get_linearized(fsmo_role_dn)));
  68                 talloc_free(sdsa);
  69                 return WERR_DS_DRA_INTERNAL_ERROR;
  70         }
  71
  72         sdsa->repsFrom1->other_info = talloc_zero(sdsa, struct repsFromTo1OtherInfo);
  73         if (!sdsa->repsFrom1->other_info) {
  74                 talloc_free(sdsa);
  75                 return WERR_NOMEM;
  76         }
  77
  78         sdsa->repsFrom1->other_info->dns_name =
  79                 talloc_asprintf(sdsa->repsFrom1->other_info, "%s._msdcs.%s",
  80                                 GUID_string(sdsa->repsFrom1->other_info, &sdsa->repsFrom1->source_dsa_obj_guid),
  81                                 lp_dnsdomain(service->task->lp_ctx));
  82         if (!sdsa->repsFrom1->other_info->dns_name) {
  83                 talloc_free(sdsa);
  84                 return WERR_NOMEM;
  85         }
  86
  87
  88         werr = dreplsrv_out_connection_attach(service, sdsa->repsFrom1, &sdsa->conn);
  89         if (!W_ERROR_IS_OK(werr)) {
  90                 DEBUG(0,(__location__ ": Failed to attach to RID manager connection\n"));
  91                 talloc_free(sdsa);
  92                 return werr;
  93         }
  94
  95         service->ridalloc.rid_manager_source_dsa = sdsa;
  96         return WERR_OK;
  97 }
  98
  99 /*
 100   called when a rid allocation request has completed
 101  */
 102 static void drepl_new_rid_pool_callback(struct dreplsrv_service *service, WERROR werr)
 103 {
 104         if (!W_ERROR_IS_OK(werr)) {
 105                 DEBUG(0,(__location__ ": RID Manager failed RID allocation - %s\n",
 106                          win_errstr(werr)));
 107         } else {
 108                 DEBUG(3,(__location__ ": RID Manager completed RID allocation OK\n"));
 109         }
 110
 111         /* don't keep the connection open to the RID Manager */
 112         talloc_free(service->ridalloc.rid_manager_source_dsa);
 113         service->ridalloc.rid_manager_source_dsa = NULL;
 114
 115         service->ridalloc.in_progress = false;
 116 }
 117
 118 /*
 119   schedule a getncchanges request to the RID Manager to ask for a new
 120   set of RIDs using DRSUAPI_EXOP_FSMO_RID_ALLOC
 121  */
 122 static WERROR drepl_request_new_rid_pool(struct dreplsrv_service *service,
 123                                          struct ldb_dn *rid_manager_dn, struct ldb_dn *fsmo_role_dn,
 124                                          uint64_t alloc_pool)
 125 {
 126         WERROR werr;
 127
 128         if (service->ridalloc.rid_manager_source_dsa == NULL) {
 129                 /* we need to establish a connection to the RID
 130                    Manager */
 131                 werr = drepl_create_rid_manager_source_dsa(service, rid_manager_dn, fsmo_role_dn);
 132                 W_ERROR_NOT_OK_RETURN(werr);
 133         }
 134
 135         service->ridalloc.in_progress = true;
 136
 137         werr = dreplsrv_schedule_partition_pull_source(service, service->ridalloc.rid_manager_source_dsa,
 138                                                        DRSUAPI_EXOP_FSMO_RID_ALLOC, alloc_pool,
 139                                                        drepl_new_rid_pool_callback);
 140         return werr;
 141 }
 142
 143
 144 /*
 145   see if we are on the last pool we have
 146  */
 147 static int drepl_ridalloc_pool_exhausted(struct ldb_context *ldb, bool *exhausted, uint64_t *alloc_pool)
 148 {
 149         struct ldb_dn *server_dn, *machine_dn, *rid_set_dn;
 150         TALLOC_CTX *tmp_ctx = talloc_new(ldb);
 151         uint64_t prev_alloc_pool;
 152         const char *attrs[] = { "rIDPreviousAllocationPool", "rIDAllocationPool", NULL };
 153         int ret;
 154         struct ldb_result *res;
 155
 156         server_dn = ldb_dn_get_parent(tmp_ctx, samdb_ntds_settings_dn(ldb));
 157         if (!server_dn) {
 158                 talloc_free(tmp_ctx);
 159                 return LDB_ERR_OPERATIONS_ERROR;
 160         }
 161
 162         ret = samdb_reference_dn(ldb, tmp_ctx, server_dn, "serverReference", &machine_dn);
 163         if (ret != LDB_SUCCESS) {
 164                 DEBUG(0,(__location__ ": Failed to find serverReference in %s - %s",
 165                          ldb_dn_get_linearized(server_dn), ldb_errstring(ldb)));
 166                 talloc_free(tmp_ctx);
 167                 return ret;
 168         }
 169
 170         ret = samdb_reference_dn(ldb, tmp_ctx, machine_dn, "rIDSetReferences", &rid_set_dn);
 171         if (ret == LDB_ERR_NO_SUCH_ATTRIBUTE) {
 172                 *exhausted = true;
 173                 talloc_free(tmp_ctx);
 174                 return LDB_SUCCESS;
 175         }
 176         if (ret != LDB_SUCCESS) {
 177                 DEBUG(0,(__location__ ": Failed to find rIDSetReferences in %s - %s",
 178                          ldb_dn_get_linearized(machine_dn), ldb_errstring(ldb)));
 179                 talloc_free(tmp_ctx);
 180                 return ret;
 181         }
 182
 183         ret = ldb_search(ldb, tmp_ctx, &res, rid_set_dn, LDB_SCOPE_BASE, attrs, NULL);
 184         if (ret != LDB_SUCCESS) {
 185                 DEBUG(0,(__location__ ": Failed to load RID Set attrs from %s - %s",
 186                          ldb_dn_get_linearized(rid_set_dn), ldb_errstring(ldb)));
 187                 talloc_free(tmp_ctx);
 188                 return ret;
 189         }
 190
 191         *alloc_pool = ldb_msg_find_attr_as_uint64(res->msgs[0], "rIDAllocationPool", 0);
 192         prev_alloc_pool = ldb_msg_find_attr_as_uint64(res->msgs[0], "rIDPreviousAllocationPool", 0);
 193
 194         if (*alloc_pool != prev_alloc_pool) {
 195                 *exhausted = false;
 196         } else {
 197                 *exhausted = true;
 198         }
 199
 200         talloc_free(tmp_ctx);
 201         return LDB_SUCCESS;
 202 }
 203
 204
 205 /*
 206   see if we are low on RIDs in the RID Set rIDAllocationPool. If we
 207   are, then schedule a replication call with DRSUAPI_EXOP_FSMO_RID_ALLOC
 208   to the RID Manager
 209  */
 210 WERROR dreplsrv_ridalloc_check_rid_pool(struct dreplsrv_service *service)
 211 {
 212         struct ldb_dn *rid_manager_dn, *fsmo_role_dn;
 213         TALLOC_CTX *tmp_ctx = talloc_new(service);
 214         struct ldb_context *ldb = service->samdb;
 215         bool exhausted;
 216         WERROR werr;
 217         int ret;
 218         uint64_t alloc_pool;
 219
 220         if (service->ridalloc.in_progress) {
 221                 talloc_free(tmp_ctx);
 222                 return WERR_OK;
 223         }
 224
 225         /*
 226           steps:
 227             - find who the RID Manager is
 228             - if we are the RID Manager then nothing to do
 229             - find our RID Set object
 230             - load rIDAllocationPool and rIDPreviousAllocationPool
 231             - if rIDAllocationPool != rIDPreviousAllocationPool then
 232               nothing to do
 233             - schedule a getncchanges with DRSUAPI_EXOP_FSMO_RID_ALLOC
 234               to the RID Manager
 235          */
 236
 237         /* work out who is the RID Manager */
 238         ret = samdb_rid_manager_dn(ldb, tmp_ctx, &rid_manager_dn);
 239         if (ret != LDB_SUCCESS) {
 240                 DEBUG(0, (__location__ ": Failed to find RID Manager object - %s", ldb_errstring(ldb)));
 241                 talloc_free(tmp_ctx);
 242                 return WERR_DS_DRA_INTERNAL_ERROR;
 243         }
 244
 245         /* find the DN of the RID Manager */
 246         ret = samdb_reference_dn(ldb, tmp_ctx, rid_manager_dn, "fSMORoleOwner", &fsmo_role_dn);
 247         if (ret != LDB_SUCCESS) {
 248                 DEBUG(0,(__location__ ": Failed to find fSMORoleOwner in RID Manager object - %s",
 249                          ldb_errstring(ldb)));
 250                 talloc_free(tmp_ctx);
 251                 return WERR_DS_DRA_INTERNAL_ERROR;
 252         }
 253
 254         if (ldb_dn_compare(samdb_ntds_settings_dn(ldb), fsmo_role_dn) == 0) {
 255                 /* we are the RID Manager - no need to do a
 256                    DRSUAPI_EXOP_FSMO_RID_ALLOC */
 257                 talloc_free(tmp_ctx);
 258                 return WERR_OK;
 259         }
 260
 261         ret = drepl_ridalloc_pool_exhausted(ldb, &exhausted, &alloc_pool);
 262         if (ret != LDB_SUCCESS) {
 263                 talloc_free(tmp_ctx);
 264                 return WERR_DS_DRA_INTERNAL_ERROR;
 265         }
 266
 267         DEBUG(2,(__location__ ": Requesting more RIDs from RID Manager\n"));
 268
 269         werr = drepl_request_new_rid_pool(service, rid_manager_dn, fsmo_role_dn, alloc_pool);
 270         talloc_free(tmp_ctx);
 271         return werr;
 272 }
 273
 274 /* called by the samldb ldb module to tell us to ask for a new RID
 275    pool */
 276 void dreplsrv_allocate_rid(struct messaging_context *msg, void *private_data,
 277                            uint32_t msg_type,
 278                            struct server_id server_id, DATA_BLOB *data)
 279 {
 280         struct dreplsrv_service *service = talloc_get_type(private_data, struct dreplsrv_service);
 281         dreplsrv_ridalloc_check_rid_pool(service);
 282 }