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(talloc_tos(), "smbXsrv_version_global.tdb");
  76         if (global_path == NULL) {
  77                 TALLOC_FREE(frame);
  78                 return NT_STATUS_NO_MEMORY;
  79         }
  80
  81         db_ctx = db_open(NULL, global_path,
  82                          0, /* hash_size */
  83                          TDB_DEFAULT |
  84                          TDB_CLEAR_IF_FIRST |
  85                          TDB_INCOMPATIBLE_HASH,
  86                          O_RDWR | O_CREAT, 0600,
  87                          DBWRAP_LOCK_ORDER_1,
  88                          DBWRAP_FLAG_NONE);
  89         if (db_ctx == NULL) {
  90                 status = map_nt_error_from_unix_common(errno);
  91                 DBG_ERR("failed to open[%s] - %s\n",
  92                         global_path,
  93                         nt_errstr(status));
  94                 TALLOC_FREE(frame);
  95                 return status;
  96         }
  97
  98         key = string_term_tdb_data(key_string);
  99
 100         db_rec = dbwrap_fetch_locked(db_ctx, db_ctx, key);
 101         if (db_rec == NULL) {
 102                 status = NT_STATUS_INTERNAL_DB_ERROR;
 103                 DBG_ERR("dbwrap_fetch_locked(%s) - %s\n",
 104                         key_string,
 105                         nt_errstr(status));
 106
 107                 TALLOC_FREE(frame);
 108                 return status;
 109         }
 110
 111         val = dbwrap_record_get_value(db_rec);
 112         if (val.dsize == 0) {
 113                 global = talloc_zero(frame, struct smbXsrv_version_global0);
 114                 if (global == NULL) {
 115                         DBG_ERR("talloc_zero failed - %s\n", __location__);
 116                         TALLOC_FREE(frame);
 117                         return NT_STATUS_NO_MEMORY;
 118                 }
 119                 global_blob = (struct smbXsrv_version_globalB) {
 120                         .version = SMBXSRV_VERSION_CURRENT,
 121                         .info.info0 = global,
 122                 };
 123         } else {
 124                 blob = data_blob_const(val.dptr, val.dsize);
 125
 126                 ndr_err = ndr_pull_struct_blob(&blob, frame, &global_blob,
 127                         (ndr_pull_flags_fn_t)ndr_pull_smbXsrv_version_globalB);
 128                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 129                         status = ndr_map_error2ntstatus(ndr_err);
 130                         DBG_ERR("ndr_pull_smbXsrv_version_globalB - %s\n",
 131                                 nt_errstr(status));
 132                         TALLOC_FREE(frame);
 133                         return status;
 134                 }
 135
 136                 switch (global_blob.version) {
 137                 case SMBXSRV_VERSION_0:
 138                         global = global_blob.info.info0;
 139                         if (global == NULL) {
 140                                 status = NT_STATUS_INTERNAL_DB_CORRUPTION;
 141                                 break;
 142                         }
 143                         status = NT_STATUS_OK;
 144                         break;
 145                 default:
 146                         status = NT_STATUS_REVISION_MISMATCH;
 147                         break;
 148                 }
 149
 150                 if (!NT_STATUS_IS_OK(status)) {
 151                         DBG_ERR("%s\n", nt_errstr(status));
 152                         NDR_PRINT_DEBUG(smbXsrv_version_globalB, &global_blob);
 153                         TALLOC_FREE(frame);
 154                         return status;
 155                 }
 156         }
 157
 158         valid = talloc_zero_array(global,
 159                                   struct smbXsrv_version_node0,
 160                                   global->num_nodes + 1);
 161         if (valid == NULL) {
 162                 DBG_ERR("talloc_zero_array failed - %s\n", __location__);
 163                 TALLOC_FREE(frame);
 164                 return NT_STATUS_NO_MEMORY;
 165         }
 166
 167         num_valid = 0;
 168         for (i=0; i < global->num_nodes; i++) {
 169                 struct smbXsrv_version_node0 *n = &global->nodes[i];
 170
 171                 exists = serverid_exists(&n->server_id);
 172                 if (!exists) {
 173                         continue;
 174                 }
 175
 176                 if (n->min_version > n->max_version) {
 177                         status = NT_STATUS_INTERNAL_DB_CORRUPTION;
 178                         DBG_ERR("%s\n", nt_errstr(status));
 179                         NDR_PRINT_DEBUG(smbXsrv_version_globalB, &global_blob);
 180                         TALLOC_FREE(frame);
 181                         return status;
 182                 }
 183
 184                 if (n->min_version > global_blob.version) {
 185                         status = NT_STATUS_INTERNAL_DB_CORRUPTION;
 186                         DBG_ERR("%s\n", 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                         DBG_ERR("%s\n", 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 = (struct smbXsrv_version_node0){
 213                 .server_id = *server_id,
 214                 .min_version = SMBXSRV_VERSION_0,
 215                 .max_version = SMBXSRV_VERSION_CURRENT,
 216                 .current_version = global_blob.version,
 217         };
 218
 219         global->num_nodes = num_valid;
 220         global->nodes = valid;
 221
 222         global_blob.seqnum += 1;
 223         global_blob.info.info0 = global;
 224
 225         ndr_err = ndr_push_struct_blob(&blob, db_rec, &global_blob,
 226                         (ndr_push_flags_fn_t)ndr_push_smbXsrv_version_globalB);
 227         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 228                 status = ndr_map_error2ntstatus(ndr_err);
 229                 DBG_ERR("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                 DBG_ERR("dbwrap_record_store - %s\n", nt_errstr(status));
 240                 TALLOC_FREE(frame);
 241                 return status;
 242         }
 243
 244         DBG_DEBUG("\n");
 245         if (DEBUGLVL(10)) {
 246                 NDR_PRINT_DEBUG(smbXsrv_version_globalB, &global_blob);
 247         }
 248
 249         smbXsrv_version_global_db_ctx = db_ctx;
 250         smbXsrv_version_global_current_version = global_blob.version;
 251
 252         TALLOC_FREE(frame);
 253         return NT_STATUS_OK;
 254 }
 255
 256 uint32_t smbXsrv_version_global_current(void)
 257 {
 258         return smbXsrv_version_global_current_version;
 259 }