s3-smbd provide struct smbd_server_connection * to conn_snum_used
[nivanova/samba-autobuild/.git] / source3 / smbd / conn.c
1 /*
2    Unix SMB/CIFS implementation.
3    Manage connections_struct structures
4    Copyright (C) Andrew Tridgell 1998
5    Copyright (C) Alexander Bokovoy 2002
6    Copyright (C) Jeremy Allison 2010
7
8    This program is free software; you can redistribute it and/or modify
9    it under the terms of the GNU General Public License as published by
10    the Free Software Foundation; either version 3 of the License, or
11    (at your option) any later version.
12
13    This program is distributed in the hope that it will be useful,
14    but WITHOUT ANY WARRANTY; without even the implied warranty of
15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16    GNU General Public License for more details.
17
18    You should have received a copy of the GNU General Public License
19    along with this program.  If not, see <http://www.gnu.org/licenses/>.
20 */
21
22 #include "includes.h"
23 #include "smbd/smbd.h"
24 #include "smbd/globals.h"
25 #include "rpc_server/rpc_ncacn_np.h"
26
27 /* The connections bitmap is expanded in increments of BITMAP_BLOCK_SZ. The
28  * maximum size of the bitmap is the largest positive integer, but you will hit
29  * the "max connections" limit, looong before that.
30  */
31
32 #define BITMAP_BLOCK_SZ 128
33
34 /****************************************************************************
35  Init the conn structures.
36 ****************************************************************************/
37
38 void conn_init(struct smbd_server_connection *sconn)
39 {
40         sconn->smb1.tcons.Connections = NULL;
41         sconn->smb1.tcons.bmap = bitmap_talloc(sconn, BITMAP_BLOCK_SZ);
42 }
43
44 /****************************************************************************
45  Return the number of open connections.
46 ****************************************************************************/
47
48 int conn_num_open(struct smbd_server_connection *sconn)
49 {
50         return sconn->num_tcons_open;
51 }
52
53 /****************************************************************************
54  Check if a snum is in use.
55 ****************************************************************************/
56
57 bool conn_snum_used(struct smbd_server_connection *sconn,
58                     int snum)
59 {
60         if (sconn->using_smb2) {
61                 /* SMB2 */
62                 struct smbd_smb2_session *sess;
63                 for (sess = sconn->smb2.sessions.list; sess; sess = sess->next) {
64                         struct smbd_smb2_tcon *ptcon;
65
66                         for (ptcon = sess->tcons.list; ptcon; ptcon = ptcon->next) {
67                                 if (ptcon->compat_conn &&
68                                                 ptcon->compat_conn->params &&
69                                                 (ptcon->compat_conn->params->service = snum)) {
70                                         return true;
71                                 }
72                         }
73                 }
74         } else {
75                 /* SMB1 */
76                 connection_struct *conn;
77                 for (conn=sconn->smb1.tcons.Connections;conn;conn=conn->next) {
78                         if (conn->params->service == snum) {
79                                 return true;
80                         }
81                 }
82         }
83         return false;
84 }
85
86 /****************************************************************************
87  Find a conn given a cnum.
88 ****************************************************************************/
89
90 connection_struct *conn_find(struct smbd_server_connection *sconn,unsigned cnum)
91 {
92         if (sconn->using_smb2) {
93                 /* SMB2 */
94                 struct smbd_smb2_session *sess;
95                 for (sess = sconn->smb2.sessions.list; sess; sess = sess->next) {
96                         struct smbd_smb2_tcon *ptcon;
97
98                         for (ptcon = sess->tcons.list; ptcon; ptcon = ptcon->next) {
99                                 if (ptcon->compat_conn &&
100                                                 ptcon->compat_conn->cnum == cnum) {
101                                         return ptcon->compat_conn;
102                                 }
103                         }
104                 }
105         } else {
106                 /* SMB1 */
107                 int count=0;
108                 connection_struct *conn;
109                 for (conn=sconn->smb1.tcons.Connections;conn;conn=conn->next,count++) {
110                         if (conn->cnum == cnum) {
111                                 if (count > 10) {
112                                         DLIST_PROMOTE(sconn->smb1.tcons.Connections,
113                                                 conn);
114                                 }
115                                 return conn;
116                         }
117                 }
118         }
119
120         return NULL;
121 }
122
123 /****************************************************************************
124  Find first available connection slot, starting from a random position.
125  The randomisation stops problems with the server dieing and clients
126  thinking the server is still available.
127 ****************************************************************************/
128
129 connection_struct *conn_new(struct smbd_server_connection *sconn)
130 {
131         connection_struct *conn;
132         int i;
133         int find_offset = 1;
134
135         if (sconn->using_smb2) {
136                 /* SMB2 */
137                 if (!(conn=TALLOC_ZERO_P(NULL, connection_struct)) ||
138                     !(conn->params = TALLOC_P(conn, struct share_params))) {
139                         DEBUG(0,("TALLOC_ZERO() failed!\n"));
140                         TALLOC_FREE(conn);
141                         return NULL;
142                 }
143                 conn->sconn = sconn;
144                 return conn;
145         }
146
147         /* SMB1 */
148 find_again:
149         i = bitmap_find(sconn->smb1.tcons.bmap, find_offset);
150
151         if (i == -1) {
152                 /* Expand the connections bitmap. */
153                 int             oldsz = sconn->smb1.tcons.bmap->n;
154                 int             newsz = sconn->smb1.tcons.bmap->n +
155                                         BITMAP_BLOCK_SZ;
156                 struct bitmap * nbmap;
157
158                 if (newsz <= oldsz) {
159                         /* Integer wrap. */
160                         DEBUG(0,("ERROR! Out of connection structures\n"));
161                         return NULL;
162                 }
163
164                 DEBUG(4,("resizing connections bitmap from %d to %d\n",
165                         oldsz, newsz));
166
167                 nbmap = bitmap_talloc(sconn, newsz);
168                 if (!nbmap) {
169                         DEBUG(0,("ERROR! malloc fail.\n"));
170                         return NULL;
171                 }
172
173                 bitmap_copy(nbmap, sconn->smb1.tcons.bmap);
174                 TALLOC_FREE(sconn->smb1.tcons.bmap);
175
176                 sconn->smb1.tcons.bmap = nbmap;
177                 find_offset = oldsz; /* Start next search in the new portion. */
178
179                 goto find_again;
180         }
181
182         /* The bitmap position is used below as the connection number
183          * conn->cnum). This ends up as the TID field in the SMB header,
184          * which is limited to 16 bits (we skip 0xffff which is the
185          * NULL TID).
186          */
187         if (i > 65534) {
188                 DEBUG(0, ("Maximum connection limit reached\n"));
189                 return NULL;
190         }
191
192         if (!(conn=TALLOC_ZERO_P(NULL, connection_struct)) ||
193             !(conn->params = TALLOC_P(conn, struct share_params))) {
194                 DEBUG(0,("TALLOC_ZERO() failed!\n"));
195                 TALLOC_FREE(conn);
196                 return NULL;
197         }
198         conn->sconn = sconn;
199         conn->cnum = i;
200         conn->force_group_gid = (gid_t)-1;
201
202         bitmap_set(sconn->smb1.tcons.bmap, i);
203
204         sconn->num_tcons_open++;
205
206         string_set(&conn->connectpath,"");
207         string_set(&conn->origpath,"");
208
209         DLIST_ADD(sconn->smb1.tcons.Connections, conn);
210
211         return conn;
212 }
213
214 /****************************************************************************
215  Close all conn structures.
216  Return true if any were closed.
217 ****************************************************************************/
218
219 bool conn_close_all(struct smbd_server_connection *sconn)
220 {
221         bool ret = false;
222         if (sconn->using_smb2) {
223                 /* SMB2 */
224                 struct smbd_smb2_session *sess;
225                 for (sess = sconn->smb2.sessions.list; sess; sess = sess->next) {
226                         struct smbd_smb2_tcon *tcon, *tc_next;
227
228                         for (tcon = sess->tcons.list; tcon; tcon = tc_next) {
229                                 tc_next = tcon->next;
230                                 TALLOC_FREE(tcon);
231                                 ret = true;
232                         }
233                 }
234         } else {
235                 /* SMB1 */
236                 connection_struct *conn, *next;
237
238                 for (conn=sconn->smb1.tcons.Connections;conn;conn=next) {
239                         next=conn->next;
240                         set_current_service(conn, 0, True);
241                         close_cnum(conn, conn->vuid);
242                         ret = true;
243                 }
244         }
245         return ret;
246 }
247
248 /****************************************************************************
249  Update last used timestamps.
250 ****************************************************************************/
251
252 static void conn_lastused_update(struct smbd_server_connection *sconn,time_t t)
253 {
254         if (sconn->using_smb2) {
255                 /* SMB2 */
256                 struct smbd_smb2_session *sess;
257                 for (sess = sconn->smb2.sessions.list; sess; sess = sess->next) {
258                         struct smbd_smb2_tcon *ptcon;
259
260                         for (ptcon = sess->tcons.list; ptcon; ptcon = ptcon->next) {
261                                 connection_struct *conn = ptcon->compat_conn;
262                                 /* Update if connection wasn't idle. */
263                                 if (conn && conn->lastused != conn->lastused_count) {
264                                         conn->lastused = t;
265                                         conn->lastused_count = t;
266                                 }
267                         }
268                 }
269         } else {
270                 /* SMB1 */
271                 connection_struct *conn;
272                 for (conn=sconn->smb1.tcons.Connections;conn;conn=conn->next) {
273                         /* Update if connection wasn't idle. */
274                         if (conn->lastused != conn->lastused_count) {
275                                 conn->lastused = t;
276                                 conn->lastused_count = t;
277                         }
278                 }
279         }
280 }
281
282 /****************************************************************************
283  Idle inactive connections.
284 ****************************************************************************/
285
286 bool conn_idle_all(struct smbd_server_connection *sconn, time_t t)
287 {
288         int deadtime = lp_deadtime()*60;
289
290         conn_lastused_update(sconn, t);
291
292         if (deadtime <= 0) {
293                 deadtime = DEFAULT_SMBD_TIMEOUT;
294         }
295
296         if (sconn->using_smb2) {
297                 /* SMB2 */
298                 struct smbd_smb2_session *sess;
299                 for (sess = sconn->smb2.sessions.list; sess; sess = sess->next) {
300                         struct smbd_smb2_tcon *ptcon;
301
302                         for (ptcon = sess->tcons.list; ptcon; ptcon = ptcon->next) {
303                                 time_t age;
304                                 connection_struct *conn = ptcon->compat_conn;
305
306                                 if (conn == NULL) {
307                                         continue;
308                                 }
309
310                                 age = t - conn->lastused;
311                                 /* close dirptrs on connections that are idle */
312                                 if (age > DPTR_IDLE_TIMEOUT) {
313                                         dptr_idlecnum(conn);
314                                 }
315
316                                 if (conn->num_files_open > 0 || age < deadtime) {
317                                         return false;
318                                 }
319                         }
320                 }
321         } else {
322                 /* SMB1 */
323                 connection_struct *conn;
324                 for (conn=sconn->smb1.tcons.Connections;conn;conn=conn->next) {
325                         time_t age = t - conn->lastused;
326
327                         /* close dirptrs on connections that are idle */
328                         if (age > DPTR_IDLE_TIMEOUT) {
329                                 dptr_idlecnum(conn);
330                         }
331
332                         if (conn->num_files_open > 0 || age < deadtime) {
333                                 return false;
334                         }
335                 }
336         }
337
338         /*
339          * Check all pipes for any open handles. We cannot
340          * idle with a handle open.
341          */
342         if (check_open_pipes()) {
343                 return false;
344         }
345
346         return true;
347 }
348
349 /****************************************************************************
350  Clear a vuid out of the validity cache, and as the 'owner' of a connection.
351 ****************************************************************************/
352
353 void conn_clear_vuid_caches(struct smbd_server_connection *sconn,uint16_t vuid)
354 {
355         connection_struct *conn;
356
357         if (sconn->using_smb2) {
358                 /* SMB2 */
359                 struct smbd_smb2_session *sess;
360                 for (sess = sconn->smb2.sessions.list; sess; sess = sess->next) {
361                         struct smbd_smb2_tcon *ptcon;
362
363                         for (ptcon = sess->tcons.list; ptcon; ptcon = ptcon->next) {
364                                 if (ptcon->compat_conn) {
365                                         if (ptcon->compat_conn->vuid == vuid) {
366                                                 ptcon->compat_conn->vuid = UID_FIELD_INVALID;
367                                         }
368                                         conn_clear_vuid_cache(ptcon->compat_conn, vuid);
369                                 }
370                         }
371                 }
372         } else {
373                 /* SMB1 */
374                 for (conn=sconn->smb1.tcons.Connections;conn;conn=conn->next) {
375                         if (conn->vuid == vuid) {
376                                 conn->vuid = UID_FIELD_INVALID;
377                         }
378                         conn_clear_vuid_cache(conn, vuid);
379                 }
380         }
381 }
382
383 /****************************************************************************
384  Free a conn structure - internal part.
385 ****************************************************************************/
386
387 static void conn_free_internal(connection_struct *conn)
388 {
389         vfs_handle_struct *handle = NULL, *thandle = NULL;
390         struct trans_state *state = NULL;
391
392         /* Free vfs_connection_struct */
393         handle = conn->vfs_handles;
394         while(handle) {
395                 thandle = handle->next;
396                 DLIST_REMOVE(conn->vfs_handles, handle);
397                 if (handle->free_data)
398                         handle->free_data(&handle->data);
399                 handle = thandle;
400         }
401
402         /* Free any pending transactions stored on this conn. */
403         for (state = conn->pending_trans; state; state = state->next) {
404                 /* state->setup is a talloc child of state. */
405                 SAFE_FREE(state->param);
406                 SAFE_FREE(state->data);
407         }
408
409         free_namearray(conn->veto_list);
410         free_namearray(conn->hide_list);
411         free_namearray(conn->veto_oplock_list);
412         free_namearray(conn->aio_write_behind_list);
413
414         string_free(&conn->connectpath);
415         string_free(&conn->origpath);
416
417         ZERO_STRUCTP(conn);
418         talloc_destroy(conn);
419 }
420
421 /****************************************************************************
422  Free a conn structure.
423 ****************************************************************************/
424
425 void conn_free(connection_struct *conn)
426 {
427         if (conn->sconn == NULL) {
428                 conn_free_internal(conn);
429                 return;
430         }
431
432         if (conn->sconn->using_smb2) {
433                 /* SMB2 */
434                 conn_free_internal(conn);
435                 return;
436         }
437
438         /* SMB1 */
439         DLIST_REMOVE(conn->sconn->smb1.tcons.Connections, conn);
440
441         if (conn->sconn->smb1.tcons.bmap != NULL) {
442                 /*
443                  * Can be NULL for fake connections created by
444                  * create_conn_struct()
445                  */
446                 bitmap_clear(conn->sconn->smb1.tcons.bmap, conn->cnum);
447         }
448
449         SMB_ASSERT(conn->sconn->num_tcons_open > 0);
450         conn->sconn->num_tcons_open--;
451
452         conn_free_internal(conn);
453 }
454
455 /****************************************************************************
456  Receive a smbcontrol message to forcibly unmount a share.
457  The message contains just a share name and all instances of that
458  share are unmounted.
459  The special sharename '*' forces unmount of all shares.
460 ****************************************************************************/
461
462 void msg_force_tdis(struct messaging_context *msg,
463                     void *private_data,
464                     uint32_t msg_type,
465                     struct server_id server_id,
466                     DATA_BLOB *data)
467 {
468         struct smbd_server_connection *sconn;
469         connection_struct *conn, *next;
470         fstring sharename;
471
472         sconn = msg_ctx_to_sconn(msg);
473         if (sconn == NULL) {
474                 DEBUG(1, ("could not find sconn\n"));
475                 return;
476         }
477
478         fstrcpy(sharename, (const char *)data->data);
479
480         if (strcmp(sharename, "*") == 0) {
481                 DEBUG(1,("Forcing close of all shares\n"));
482                 conn_close_all(sconn);
483                 return;
484         }
485
486         if (sconn->using_smb2) {
487                 /* SMB2 */
488                 struct smbd_smb2_session *sess;
489                 for (sess = sconn->smb2.sessions.list; sess; sess = sess->next) {
490                         struct smbd_smb2_tcon *tcon, *tc_next;
491
492                         for (tcon = sess->tcons.list; tcon; tcon = tc_next) {
493                                 tc_next = tcon->next;
494                                 if (tcon->compat_conn &&
495                                                 strequal(lp_servicename(SNUM(tcon->compat_conn)),
496                                                                 sharename)) {
497                                         DEBUG(1,("Forcing close of share %s cnum=%d\n",
498                                                 sharename, tcon->compat_conn->cnum));
499                                         TALLOC_FREE(tcon);
500                                 }
501                         }
502                 }
503         } else {
504                 /* SMB1 */
505                 for (conn=sconn->smb1.tcons.Connections;conn;conn=next) {
506                         next=conn->next;
507                         if (strequal(lp_servicename(SNUM(conn)), sharename)) {
508                                 DEBUG(1,("Forcing close of share %s cnum=%d\n",
509                                         sharename, conn->cnum));
510                                 close_cnum(conn, (uint16)-1);
511                         }
512                 }
513         }
514 }