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         if (db_ctx == NULL) {
  85                 status = map_nt_error_from_unix_common(errno);
  86                 DEBUG(0,("smbXsrv_version_global_init: "
  87                          "failed to open[%s] - %s\n",
  88                          global_path, nt_errstr(status)));
  89                 TALLOC_FREE(frame);
  90                 return status;
  91         }
  92
  93         key = string_term_tdb_data(key_string);
  94
  95         db_rec = dbwrap_fetch_locked(db_ctx, db_ctx, key);
  96         if (db_rec == NULL) {
  97                 status = NT_STATUS_INTERNAL_DB_ERROR;
  98                 DEBUG(0,("smbXsrv_version_global_init: "
  99                          "dbwrap_fetch_locked(%s) - %s\n",
 100                          key_string, nt_errstr(status)));
 101                 TALLOC_FREE(frame);
 102                 return status;
 103         }
 104
 105         val = dbwrap_record_get_value(db_rec);
 106         if (val.dsize == 0) {
 107                 global = talloc_zero(frame, struct smbXsrv_version_global0);
 108                 if (global == NULL) {
 109                         DEBUG(0,("smbXsrv_version_global_init: "
 110                                  "talloc_zero failed - %s\n", __location__));
 111                         TALLOC_FREE(frame);
 112                         return NT_STATUS_NO_MEMORY;
 113                 }
 114                 ZERO_STRUCT(global_blob);
 115                 global_blob.version = SMBXSRV_VERSION_CURRENT;
 116                 global_blob.info.info0 = global;
 117         } else {
 118                 blob = data_blob_const(val.dptr, val.dsize);
 119
 120                 ndr_err = ndr_pull_struct_blob(&blob, frame, &global_blob,
 121                         (ndr_pull_flags_fn_t)ndr_pull_smbXsrv_version_globalB);
 122                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 123                         status = ndr_map_error2ntstatus(ndr_err);
 124                         DEBUG(0,("smbXsrv_version_global_init: "
 125                                  "ndr_pull_smbXsrv_version_globalB - %s\n",
 126                                  nt_errstr(status)));
 127                         TALLOC_FREE(frame);
 128                         return status;
 129                 }
 130
 131                 switch (global_blob.version) {
 132                 case SMBXSRV_VERSION_0:
 133                         global = global_blob.info.info0;
 134                         if (global == NULL) {
 135                                 status = NT_STATUS_INTERNAL_DB_CORRUPTION;
 136                                 break;
 137                         }
 138                         status = NT_STATUS_OK;
 139                         break;
 140                 default:
 141                         status = NT_STATUS_REVISION_MISMATCH;
 142                         break;
 143                 }
 144
 145                 if (!NT_STATUS_IS_OK(status)) {
 146                         DEBUG(0,("smbXsrv_version_global_init - %s\n",
 147                                  nt_errstr(status)));
 148                         NDR_PRINT_DEBUG(smbXsrv_version_globalB, &global_blob);
 149                         TALLOC_FREE(frame);
 150                         return status;
 151                 }
 152         }
 153
 154         valid = talloc_zero_array(global,
 155                                   struct smbXsrv_version_node0,
 156                                   global->num_nodes + 1);
 157         if (valid == NULL) {
 158                 DEBUG(0,("smbXsrv_version_global_init: "
 159                          "talloc_zero_array failed - %s\n", __location__));
 160                 TALLOC_FREE(frame);
 161                 return NT_STATUS_NO_MEMORY;
 162         }
 163
 164         num_valid = 0;
 165         for (i=0; i < global->num_nodes; i++) {
 166                 struct smbXsrv_version_node0 *n = &global->nodes[i];
 167
 168                 exists = serverid_exists(&n->server_id);
 169                 if (!exists) {
 170                         continue;
 171                 }
 172
 173                 if (n->min_version > n->max_version) {
 174                         status = NT_STATUS_INTERNAL_DB_CORRUPTION;
 175                         DEBUG(0,("smbXsrv_version_global_init - %s\n",
 176                                  nt_errstr(status)));
 177                         NDR_PRINT_DEBUG(smbXsrv_version_globalB, &global_blob);
 178                         TALLOC_FREE(frame);
 179                         return status;
 180                 }
 181
 182                 if (n->min_version > global_blob.version) {
 183                         status = NT_STATUS_INTERNAL_DB_CORRUPTION;
 184                         DEBUG(0,("smbXsrv_version_global_init - %s\n",
 185                                  nt_errstr(status)));
 186                         NDR_PRINT_DEBUG(smbXsrv_version_globalB, &global_blob);
 187                         TALLOC_FREE(frame);
 188                         return status;
 189                 }
 190
 191                 if (n->max_version < global_blob.version) {
 192                         status = NT_STATUS_INTERNAL_DB_CORRUPTION;
 193                         DEBUG(0,("smbXsrv_version_global_init - %s\n",
 194                                  nt_errstr(status)));
 195                         NDR_PRINT_DEBUG(smbXsrv_version_globalB, &global_blob);
 196                         TALLOC_FREE(frame);
 197                         return status;
 198                 }
 199
 200                 valid[num_valid] = *n;
 201                 if (server_id->vnn == n->server_id.vnn) {
 202                         local_node = &valid[num_valid];
 203                 }
 204                 num_valid++;
 205         }
 206
 207         if (local_node == NULL) {
 208                 local_node = &valid[num_valid];
 209                 num_valid++;
 210         }
 211
 212         local_node->server_id = *server_id;
 213         local_node->min_version = SMBXSRV_VERSION_0;
 214         local_node->max_version = SMBXSRV_VERSION_CURRENT;
 215         local_node->current_version = global_blob.version;
 216
 217         global->num_nodes = num_valid;
 218         global->nodes = valid;
 219
 220         global_blob.seqnum += 1;
 221         global_blob.info.info0 = global;
 222
 223         ndr_err = ndr_push_struct_blob(&blob, db_rec, &global_blob,
 224                         (ndr_push_flags_fn_t)ndr_push_smbXsrv_version_globalB);
 225         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 226                 status = ndr_map_error2ntstatus(ndr_err);
 227                 DEBUG(0,("smbXsrv_version_global_init: "
 228                          "ndr_push_smbXsrv_version_globalB - %s\n",
 229                          nt_errstr(status)));
 230                 TALLOC_FREE(frame);
 231                 return status;
 232         }
 233
 234         val = make_tdb_data(blob.data, blob.length);
 235         status = dbwrap_record_store(db_rec, val, TDB_REPLACE);
 236         TALLOC_FREE(db_rec);
 237         if (!NT_STATUS_IS_OK(status)) {
 238                 DEBUG(0,("smbXsrv_version_global_init: "
 239                          "dbwrap_record_store - %s\n",
 240                          nt_errstr(status)));
 241                 TALLOC_FREE(frame);
 242                 return status;
 243         }
 244
 245         DEBUG(10,("smbXsrv_version_global_init\n"));
 246         if (DEBUGLVL(10)) {
 247                 NDR_PRINT_DEBUG(smbXsrv_version_globalB, &global_blob);
 248         }
 249
 250         smbXsrv_version_global_db_ctx = db_ctx;
 251         smbXsrv_version_global_current_version = global_blob.version;
 252
 253         TALLOC_FREE(frame);
 254         return NT_STATUS_OK;
 255 }
 256
 257 uint32_t smbXsrv_version_global_current(void)
 258 {
 259         return smbXsrv_version_global_current_version;
 260 }