source3/smbd/smbXsrv_version.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    Copyright (C) Stefan Metzmacher 2012
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "includes.h"
  21 #include "system/filesys.h"
  22 #include "smbd/globals.h"
  23 #include "dbwrap/dbwrap.h"
  24 #include "dbwrap/dbwrap_open.h"
  25 #include "lib/util/util_tdb.h"
  26 #include "librpc/gen_ndr/ndr_smbXsrv.h"
  27 #include "serverid.h"
  28
  29 /*
  30  * This implements a version scheme for file server internal
  31  * states. smbXsrv_version_global.tdb stores the possible
  32  * and current versions of structure formats (struct smbXsrv_*_global)
  33  * per cluster node.
  34  *
  35  * If the supported versions doesn't match a version of any
  36  * of the other nodes, it refused to start.
  37  *
  38  * This should prevent silent corruption of the internal
  39  * databases and structures, if two incompatible implementations
  40  * read and write.
  41  *
  42  * In future this can be used to implement rolling code upgrades
  43  * in a cluster, but for now it is simple.
  44  */
  45
  46 static struct db_context *smbXsrv_version_global_db_ctx = NULL;
  47 static uint32_t smbXsrv_version_global_current_version = UINT32_MAX;
  48
  49 NTSTATUS smbXsrv_version_global_init(const struct server_id *server_id)
  50 {
  51         const char *global_path = NULL;
  52         struct db_context *db_ctx = NULL;
  53         struct db_record *db_rec = NULL;
  54         TDB_DATA key;
  55         TDB_DATA val;
  56         DATA_BLOB blob;
  57         struct smbXsrv_version_globalB global_blob;
  58         enum ndr_err_code ndr_err;
  59         struct smbXsrv_version_global0 *global = NULL;
  60         uint32_t i;
  61         uint32_t num_valid = 0;
  62         struct smbXsrv_version_node0 *valid = NULL;
  63         struct smbXsrv_version_node0 *local_node = NULL;
  64         bool exists;
  65         NTSTATUS status;
  66         const char *key_string = "smbXsrv_version_global";
  67         TALLOC_CTX *frame;
  68
  69         if (smbXsrv_version_global_db_ctx != NULL) {
  70                 return NT_STATUS_OK;
  71         }
  72
  73         frame = talloc_stackframe();
  74
  75         global_path = lock_path("smbXsrv_version_global.tdb");
  76
  77         db_ctx = db_open(NULL, global_path,
  78                          0, /* hash_size */
  79                          TDB_DEFAULT |
  80                          TDB_CLEAR_IF_FIRST |
  81                          TDB_INCOMPATIBLE_HASH,
  82                          O_RDWR | O_CREAT, 0600,
  83                          DBWRAP_LOCK_ORDER_1,
  84                          DBWRAP_FLAG_NONE);
  85         if (db_ctx == NULL) {
  86                 status = map_nt_error_from_unix_common(errno);
  87                 DEBUG(0,("smbXsrv_version_global_init: "
  88                          "failed to open[%s] - %s\n",
  89                          global_path, nt_errstr(status)));
  90                 TALLOC_FREE(frame);
  91                 return status;
  92         }
  93
  94         key = string_term_tdb_data(key_string);
  95
  96         db_rec = dbwrap_fetch_locked(db_ctx, db_ctx, key);
  97         if (db_rec == NULL) {
  98                 status = NT_STATUS_INTERNAL_DB_ERROR;
  99                 DEBUG(0,("smbXsrv_version_global_init: "
 100                          "dbwrap_fetch_locked(%s) - %s\n",
 101                          key_string, nt_errstr(status)));
 102                 TALLOC_FREE(frame);
 103                 return status;
 104         }
 105
 106         val = dbwrap_record_get_value(db_rec);
 107         if (val.dsize == 0) {
 108                 global = talloc_zero(frame, struct smbXsrv_version_global0);
 109                 if (global == NULL) {
 110                         DEBUG(0,("smbXsrv_version_global_init: "
 111                                  "talloc_zero failed - %s\n", __location__));
 112                         TALLOC_FREE(frame);
 113                         return NT_STATUS_NO_MEMORY;
 114                 }
 115                 ZERO_STRUCT(global_blob);
 116                 global_blob.version = SMBXSRV_VERSION_CURRENT;
 117                 global_blob.info.info0 = global;
 118         } else {
 119                 blob = data_blob_const(val.dptr, val.dsize);
 120
 121                 ndr_err = ndr_pull_struct_blob(&blob, frame, &global_blob,
 122                         (ndr_pull_flags_fn_t)ndr_pull_smbXsrv_version_globalB);
 123                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 124                         status = ndr_map_error2ntstatus(ndr_err);
 125                         DEBUG(0,("smbXsrv_version_global_init: "
 126                                  "ndr_pull_smbXsrv_version_globalB - %s\n",
 127                                  nt_errstr(status)));
 128                         TALLOC_FREE(frame);
 129                         return status;
 130                 }
 131
 132                 switch (global_blob.version) {
 133                 case SMBXSRV_VERSION_0:
 134                         global = global_blob.info.info0;
 135                         if (global == NULL) {
 136                                 status = NT_STATUS_INTERNAL_DB_CORRUPTION;
 137                                 break;
 138                         }
 139                         status = NT_STATUS_OK;
 140                         break;
 141                 default:
 142                         status = NT_STATUS_REVISION_MISMATCH;
 143                         break;
 144                 }
 145
 146                 if (!NT_STATUS_IS_OK(status)) {
 147                         DEBUG(0,("smbXsrv_version_global_init - %s\n",
 148                                  nt_errstr(status)));
 149                         NDR_PRINT_DEBUG(smbXsrv_version_globalB, &global_blob);
 150                         TALLOC_FREE(frame);
 151                         return status;
 152                 }
 153         }
 154
 155         valid = talloc_zero_array(global,
 156                                   struct smbXsrv_version_node0,
 157                                   global->num_nodes + 1);
 158         if (valid == NULL) {
 159                 DEBUG(0,("smbXsrv_version_global_init: "
 160                          "talloc_zero_array failed - %s\n", __location__));
 161                 TALLOC_FREE(frame);
 162                 return NT_STATUS_NO_MEMORY;
 163         }
 164
 165         num_valid = 0;
 166         for (i=0; i < global->num_nodes; i++) {
 167                 struct smbXsrv_version_node0 *n = &global->nodes[i];
 168
 169                 exists = serverid_exists(&n->server_id);
 170                 if (!exists) {
 171                         continue;
 172                 }
 173
 174                 if (n->min_version > n->max_version) {
 175                         status = NT_STATUS_INTERNAL_DB_CORRUPTION;
 176                         DEBUG(0,("smbXsrv_version_global_init - %s\n",
 177                                  nt_errstr(status)));
 178                         NDR_PRINT_DEBUG(smbXsrv_version_globalB, &global_blob);
 179                         TALLOC_FREE(frame);
 180                         return status;
 181                 }
 182
 183                 if (n->min_version > global_blob.version) {
 184                         status = NT_STATUS_INTERNAL_DB_CORRUPTION;
 185                         DEBUG(0,("smbXsrv_version_global_init - %s\n",
 186                                  nt_errstr(status)));
 187                         NDR_PRINT_DEBUG(smbXsrv_version_globalB, &global_blob);
 188                         TALLOC_FREE(frame);
 189                         return status;
 190                 }
 191
 192                 if (n->max_version < global_blob.version) {
 193                         status = NT_STATUS_INTERNAL_DB_CORRUPTION;
 194                         DEBUG(0,("smbXsrv_version_global_init - %s\n",
 195                                  nt_errstr(status)));
 196                         NDR_PRINT_DEBUG(smbXsrv_version_globalB, &global_blob);
 197                         TALLOC_FREE(frame);
 198                         return status;
 199                 }
 200
 201                 valid[num_valid] = *n;
 202                 if (server_id->vnn == n->server_id.vnn) {
 203                         local_node = &valid[num_valid];
 204                 }
 205                 num_valid++;
 206         }
 207
 208         if (local_node == NULL) {
 209                 local_node = &valid[num_valid];
 210                 num_valid++;
 211         }
 212
 213         local_node->server_id = *server_id;
 214         local_node->min_version = SMBXSRV_VERSION_0;
 215         local_node->max_version = SMBXSRV_VERSION_CURRENT;
 216         local_node->current_version = global_blob.version;
 217
 218         global->num_nodes = num_valid;
 219         global->nodes = valid;
 220
 221         global_blob.seqnum += 1;
 222         global_blob.info.info0 = global;
 223
 224         ndr_err = ndr_push_struct_blob(&blob, db_rec, &global_blob,
 225                         (ndr_push_flags_fn_t)ndr_push_smbXsrv_version_globalB);
 226         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 227                 status = ndr_map_error2ntstatus(ndr_err);
 228                 DEBUG(0,("smbXsrv_version_global_init: "
 229                          "ndr_push_smbXsrv_version_globalB - %s\n",
 230                          nt_errstr(status)));
 231                 TALLOC_FREE(frame);
 232                 return status;
 233         }
 234
 235         val = make_tdb_data(blob.data, blob.length);
 236         status = dbwrap_record_store(db_rec, val, TDB_REPLACE);
 237         TALLOC_FREE(db_rec);
 238         if (!NT_STATUS_IS_OK(status)) {
 239                 DEBUG(0,("smbXsrv_version_global_init: "
 240                          "dbwrap_record_store - %s\n",
 241                          nt_errstr(status)));
 242                 TALLOC_FREE(frame);
 243                 return status;
 244         }
 245
 246         DEBUG(10,("smbXsrv_version_global_init\n"));
 247         if (DEBUGLVL(10)) {
 248                 NDR_PRINT_DEBUG(smbXsrv_version_globalB, &global_blob);
 249         }
 250
 251         smbXsrv_version_global_db_ctx = db_ctx;
 252         smbXsrv_version_global_current_version = global_blob.version;
 253
 254         TALLOC_FREE(frame);
 255         return NT_STATUS_OK;
 256 }
 257
 258 uint32_t smbXsrv_version_global_current(void)
 259 {
 260         return smbXsrv_version_global_current_version;
 261 }