2 Unix SMB/CIFS implementation.
3 Implementation of a reliable server_exists()
4 Copyright (C) Volker Lendecke 2010
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.
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.
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/>.
21 #include "system/filesys.h"
30 struct serverid_data {
35 bool serverid_parent_init(TALLOC_CTX *mem_ctx)
40 * Open the tdb in the parent process (smbd) so that our
41 * CLEAR_IF_FIRST optimization in tdb_reopen_all can properly
45 db = tdb_wrap_open(mem_ctx, lock_path("serverid.tdb"),
46 0, TDB_DEFAULT|TDB_CLEAR_IF_FIRST|TDB_INCOMPATIBLE_HASH, O_RDWR|O_CREAT,
49 DEBUG(1, ("could not open serverid.tdb: %s\n",
56 static struct db_context *serverid_db(void)
58 static struct db_context *db;
63 db = db_open(NULL, lock_path("serverid.tdb"), 0,
64 TDB_DEFAULT|TDB_CLEAR_IF_FIRST|TDB_INCOMPATIBLE_HASH, O_RDWR|O_CREAT, 0644);
68 static void serverid_fill_key(const struct server_id *id,
69 struct serverid_key *key)
76 bool serverid_register(const struct server_id id, uint32_t msg_flags)
78 struct db_context *db;
79 struct serverid_key key;
80 struct serverid_data data;
81 struct db_record *rec;
82 TDB_DATA tdbkey, tdbdata;
91 serverid_fill_key(&id, &key);
92 tdbkey = make_tdb_data((uint8_t *)&key, sizeof(key));
94 rec = db->fetch_locked(db, talloc_tos(), tdbkey);
96 DEBUG(1, ("Could not fetch_lock serverid.tdb record\n"));
101 data.unique_id = id.unique_id;
102 data.msg_flags = msg_flags;
104 tdbdata = make_tdb_data((uint8_t *)&data, sizeof(data));
105 status = rec->store(rec, tdbdata, 0);
106 if (!NT_STATUS_IS_OK(status)) {
107 DEBUG(1, ("Storing serverid.tdb record failed: %s\n",
117 bool serverid_register_msg_flags(const struct server_id id, bool do_reg,
120 struct db_context *db;
121 struct serverid_key key;
122 struct serverid_data *data;
123 struct db_record *rec;
133 serverid_fill_key(&id, &key);
134 tdbkey = make_tdb_data((uint8_t *)&key, sizeof(key));
136 rec = db->fetch_locked(db, talloc_tos(), tdbkey);
138 DEBUG(1, ("Could not fetch_lock serverid.tdb record\n"));
142 if (rec->value.dsize != sizeof(struct serverid_data)) {
143 DEBUG(1, ("serverid record has unexpected size %d "
144 "(wanted %d)\n", (int)rec->value.dsize,
145 (int)sizeof(struct serverid_data)));
149 data = (struct serverid_data *)rec->value.dptr;
152 data->msg_flags |= msg_flags;
154 data->msg_flags &= ~msg_flags;
157 status = rec->store(rec, rec->value, 0);
158 if (!NT_STATUS_IS_OK(status)) {
159 DEBUG(1, ("Storing serverid.tdb record failed: %s\n",
169 bool serverid_deregister(struct server_id id)
171 struct db_context *db;
172 struct serverid_key key;
173 struct db_record *rec;
183 serverid_fill_key(&id, &key);
184 tdbkey = make_tdb_data((uint8_t *)&key, sizeof(key));
186 rec = db->fetch_locked(db, talloc_tos(), tdbkey);
188 DEBUG(1, ("Could not fetch_lock serverid.tdb record\n"));
192 status = rec->delete_rec(rec);
193 if (!NT_STATUS_IS_OK(status)) {
194 DEBUG(1, ("Deleting serverid.tdb record failed: %s\n",
204 struct serverid_exists_state {
205 const struct server_id *id;
209 static int server_exists_parse(TDB_DATA key, TDB_DATA data, void *priv)
211 struct serverid_exists_state *state =
212 (struct serverid_exists_state *)priv;
214 if (data.dsize != sizeof(struct serverid_data)) {
219 * Use memcmp, not direct compare. data.dptr might not be
222 state->exists = (memcmp(&state->id->unique_id, data.dptr,
223 sizeof(state->id->unique_id)) == 0);
227 bool serverid_exists(const struct server_id *id)
229 struct db_context *db;
230 struct serverid_exists_state state;
231 struct serverid_key key;
234 if (lp_clustering() && !process_exists(*id)) {
243 serverid_fill_key(id, &key);
244 tdbkey = make_tdb_data((uint8_t *)&key, sizeof(key));
247 state.exists = false;
249 if (db->parse_record(db, tdbkey, server_exists_parse, &state) == -1) {
255 static bool serverid_rec_parse(const struct db_record *rec,
256 struct server_id *id, uint32_t *msg_flags)
258 struct serverid_key key;
259 struct serverid_data data;
261 if (rec->key.dsize != sizeof(key)) {
262 DEBUG(1, ("Found invalid key length %d in serverid.tdb\n",
263 (int)rec->key.dsize));
266 if (rec->value.dsize != sizeof(data)) {
267 DEBUG(1, ("Found invalid value length %d in serverid.tdb\n",
268 (int)rec->value.dsize));
272 memcpy(&key, rec->key.dptr, sizeof(key));
273 memcpy(&data, rec->value.dptr, sizeof(data));
277 id->unique_id = data.unique_id;
278 *msg_flags = data.msg_flags;
282 struct serverid_traverse_read_state {
283 int (*fn)(const struct server_id *id, uint32_t msg_flags,
288 static int serverid_traverse_read_fn(struct db_record *rec, void *private_data)
290 struct serverid_traverse_read_state *state =
291 (struct serverid_traverse_read_state *)private_data;
295 if (!serverid_rec_parse(rec, &id, &msg_flags)) {
298 return state->fn(&id, msg_flags,state->private_data);
301 bool serverid_traverse_read(int (*fn)(const struct server_id *id,
302 uint32_t msg_flags, void *private_data),
305 struct db_context *db;
306 struct serverid_traverse_read_state state;
313 state.private_data = private_data;
314 return db->traverse_read(db, serverid_traverse_read_fn, &state);
317 struct serverid_traverse_state {
318 int (*fn)(struct db_record *rec, const struct server_id *id,
319 uint32_t msg_flags, void *private_data);
323 static int serverid_traverse_fn(struct db_record *rec, void *private_data)
325 struct serverid_traverse_state *state =
326 (struct serverid_traverse_state *)private_data;
330 if (!serverid_rec_parse(rec, &id, &msg_flags)) {
333 return state->fn(rec, &id, msg_flags, state->private_data);
336 bool serverid_traverse(int (*fn)(struct db_record *rec,
337 const struct server_id *id,
338 uint32_t msg_flags, void *private_data),
341 struct db_context *db;
342 struct serverid_traverse_state state;
349 state.private_data = private_data;
350 return db->traverse(db, serverid_traverse_fn, &state);