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"
25 #include "lib/util/tdb_wrap.h"
33 struct serverid_data {
38 bool serverid_parent_init(TALLOC_CTX *mem_ctx)
43 * Open the tdb in the parent process (smbd) so that our
44 * CLEAR_IF_FIRST optimization in tdb_reopen_all can properly
48 db = tdb_wrap_open(mem_ctx, lock_path("serverid.tdb"),
49 0, TDB_DEFAULT|TDB_CLEAR_IF_FIRST|TDB_INCOMPATIBLE_HASH, O_RDWR|O_CREAT,
52 DEBUG(1, ("could not open serverid.tdb: %s\n",
59 static struct db_context *serverid_db(void)
61 static struct db_context *db;
66 db = db_open(NULL, lock_path("serverid.tdb"), 0,
67 TDB_DEFAULT|TDB_CLEAR_IF_FIRST|TDB_INCOMPATIBLE_HASH, O_RDWR|O_CREAT, 0644);
71 static void serverid_fill_key(const struct server_id *id,
72 struct serverid_key *key)
76 key->task_id = id->task_id;
80 bool serverid_register(const struct server_id id, uint32_t msg_flags)
82 struct db_context *db;
83 struct serverid_key key;
84 struct serverid_data data;
85 struct db_record *rec;
86 TDB_DATA tdbkey, tdbdata;
95 serverid_fill_key(&id, &key);
96 tdbkey = make_tdb_data((uint8_t *)&key, sizeof(key));
98 rec = db->fetch_locked(db, talloc_tos(), tdbkey);
100 DEBUG(1, ("Could not fetch_lock serverid.tdb record\n"));
105 data.unique_id = id.unique_id;
106 data.msg_flags = msg_flags;
108 tdbdata = make_tdb_data((uint8_t *)&data, sizeof(data));
109 status = rec->store(rec, tdbdata, 0);
110 if (!NT_STATUS_IS_OK(status)) {
111 DEBUG(1, ("Storing serverid.tdb record failed: %s\n",
121 bool serverid_register_msg_flags(const struct server_id id, bool do_reg,
124 struct db_context *db;
125 struct serverid_key key;
126 struct serverid_data *data;
127 struct db_record *rec;
137 serverid_fill_key(&id, &key);
138 tdbkey = make_tdb_data((uint8_t *)&key, sizeof(key));
140 rec = db->fetch_locked(db, talloc_tos(), tdbkey);
142 DEBUG(1, ("Could not fetch_lock serverid.tdb record\n"));
146 if (rec->value.dsize != sizeof(struct serverid_data)) {
147 DEBUG(1, ("serverid record has unexpected size %d "
148 "(wanted %d)\n", (int)rec->value.dsize,
149 (int)sizeof(struct serverid_data)));
153 data = (struct serverid_data *)rec->value.dptr;
156 data->msg_flags |= msg_flags;
158 data->msg_flags &= ~msg_flags;
161 status = rec->store(rec, rec->value, 0);
162 if (!NT_STATUS_IS_OK(status)) {
163 DEBUG(1, ("Storing serverid.tdb record failed: %s\n",
173 bool serverid_deregister(struct server_id id)
175 struct db_context *db;
176 struct serverid_key key;
177 struct db_record *rec;
187 serverid_fill_key(&id, &key);
188 tdbkey = make_tdb_data((uint8_t *)&key, sizeof(key));
190 rec = db->fetch_locked(db, talloc_tos(), tdbkey);
192 DEBUG(1, ("Could not fetch_lock serverid.tdb record\n"));
196 status = rec->delete_rec(rec);
197 if (!NT_STATUS_IS_OK(status)) {
198 DEBUG(1, ("Deleting serverid.tdb record failed: %s\n",
208 struct serverid_exists_state {
209 const struct server_id *id;
213 static int server_exists_parse(TDB_DATA key, TDB_DATA data, void *priv)
215 struct serverid_exists_state *state =
216 (struct serverid_exists_state *)priv;
218 if (data.dsize != sizeof(struct serverid_data)) {
223 * Use memcmp, not direct compare. data.dptr might not be
226 state->exists = (memcmp(&state->id->unique_id, data.dptr,
227 sizeof(state->id->unique_id)) == 0);
231 bool serverid_exists(const struct server_id *id)
233 struct db_context *db;
234 struct serverid_exists_state state;
235 struct serverid_key key;
238 if (lp_clustering() && !process_exists(*id)) {
247 serverid_fill_key(id, &key);
248 tdbkey = make_tdb_data((uint8_t *)&key, sizeof(key));
251 state.exists = false;
253 if (db->parse_record(db, tdbkey, server_exists_parse, &state) != 0) {
259 static bool serverid_rec_parse(const struct db_record *rec,
260 struct server_id *id, uint32_t *msg_flags)
262 struct serverid_key key;
263 struct serverid_data data;
265 if (rec->key.dsize != sizeof(key)) {
266 DEBUG(1, ("Found invalid key length %d in serverid.tdb\n",
267 (int)rec->key.dsize));
270 if (rec->value.dsize != sizeof(data)) {
271 DEBUG(1, ("Found invalid value length %d in serverid.tdb\n",
272 (int)rec->value.dsize));
276 memcpy(&key, rec->key.dptr, sizeof(key));
277 memcpy(&data, rec->value.dptr, sizeof(data));
280 id->task_id = key.task_id;
282 id->unique_id = data.unique_id;
283 *msg_flags = data.msg_flags;
287 struct serverid_traverse_read_state {
288 int (*fn)(const struct server_id *id, uint32_t msg_flags,
293 static int serverid_traverse_read_fn(struct db_record *rec, void *private_data)
295 struct serverid_traverse_read_state *state =
296 (struct serverid_traverse_read_state *)private_data;
300 if (!serverid_rec_parse(rec, &id, &msg_flags)) {
303 return state->fn(&id, msg_flags,state->private_data);
306 bool serverid_traverse_read(int (*fn)(const struct server_id *id,
307 uint32_t msg_flags, void *private_data),
310 struct db_context *db;
311 struct serverid_traverse_read_state state;
318 state.private_data = private_data;
319 return db->traverse_read(db, serverid_traverse_read_fn, &state);
322 struct serverid_traverse_state {
323 int (*fn)(struct db_record *rec, const struct server_id *id,
324 uint32_t msg_flags, void *private_data);
328 static int serverid_traverse_fn(struct db_record *rec, void *private_data)
330 struct serverid_traverse_state *state =
331 (struct serverid_traverse_state *)private_data;
335 if (!serverid_rec_parse(rec, &id, &msg_flags)) {
338 return state->fn(rec, &id, msg_flags, state->private_data);
341 bool serverid_traverse(int (*fn)(struct db_record *rec,
342 const struct server_id *id,
343 uint32_t msg_flags, void *private_data),
346 struct db_context *db;
347 struct serverid_traverse_state state;
354 state.private_data = private_data;
355 return db->traverse(db, serverid_traverse_fn, &state);