source/smbd/connection.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    connection claim routines
   4    Copyright (C) Andrew Tridgell 1998
   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
  22 /****************************************************************************
  23  Delete a connection record.
  24 ****************************************************************************/
  25
  26 BOOL yield_connection(connection_struct *conn, const char *name)
  27 {
  28         struct db_record *rec;
  29         NTSTATUS status;
  30
  31         DEBUG(3,("Yielding connection to %s\n",name));
  32
  33         if (!(rec = connections_fetch_entry(NULL, conn, name))) {
  34                 DEBUG(0, ("connections_fetch_entry failed\n"));
  35                 return False;
  36         }
  37
  38         status = rec->delete_rec(rec);
  39         if (!NT_STATUS_IS_OK(status)) {
  40                 DEBUG( NT_STATUS_EQUAL(status, NT_STATUS_NOT_FOUND) ? 3 : 0,
  41                        ("deleting connection record returned %s\n",
  42                         nt_errstr(status)));
  43         }
  44
  45         TALLOC_FREE(rec);
  46         return NT_STATUS_IS_OK(status);
  47 }
  48
  49 struct count_stat {
  50         pid_t mypid;
  51         int curr_connections;
  52         const char *name;
  53         BOOL Clear;
  54 };
  55
  56 /****************************************************************************
  57  Count the entries belonging to a service in the connection db.
  58 ****************************************************************************/
  59
  60 static int count_fn(struct db_record *rec,
  61                     const struct connections_key *ckey,
  62                     const struct connections_data *crec,
  63                     void *udp)
  64 {
  65         struct count_stat *cs = (struct count_stat *)udp;
  66
  67         if (crec->cnum == -1) {
  68                 return 0;
  69         }
  70
  71         /* If the pid was not found delete the entry from connections.tdb */
  72
  73         if (cs->Clear && !process_exists(crec->pid) && (errno == ESRCH)) {
  74                 NTSTATUS status;
  75                 DEBUG(2,("pid %s doesn't exist - deleting connections %d [%s]\n",
  76                          procid_str_static(&crec->pid), crec->cnum,
  77                          crec->servicename));
  78
  79                 status = rec->delete_rec(rec);
  80                 if (!NT_STATUS_IS_OK(status)) {
  81                         DEBUG(0,("count_fn: tdb_delete failed with error %s\n",
  82                                  nt_errstr(status)));
  83                 }
  84                 return 0;
  85         }
  86
  87         if (cs->name) {
  88                 /* We are counting all the connections to a given share. */
  89                 if (strequal(crec->servicename, cs->name)) {
  90                         cs->curr_connections++;
  91                 }
  92         } else {
  93                 /* We are counting all the connections. Static registrations
  94                  * like the lpq backgroud process and the smbd daemon process
  95                  * have a cnum of -1, so won't be counted here.
  96                  */
  97                 cs->curr_connections++;
  98         }
  99
 100         return 0;
 101 }
 102
 103 /****************************************************************************
 104  Claim an entry in the connections database.
 105 ****************************************************************************/
 106
 107 int count_current_connections( const char *sharename, BOOL clear  )
 108 {
 109         struct count_stat cs;
 110
 111         cs.mypid = sys_getpid();
 112         cs.curr_connections = 0;
 113         cs.name = sharename;
 114         cs.Clear = clear;
 115
 116         /*
 117          * This has a race condition, but locking the chain before hand is worse
 118          * as it leads to deadlock.
 119          */
 120
 121         if (connections_forall(count_fn, &cs) == -1) {
 122                 DEBUG(0,("count_current_connections: traverse of "
 123                          "connections.tdb failed\n"));
 124                 DEBUGADD(0, ("count_current_connections: connection count of %d might not be accurate",
 125                             cs.curr_connections));
 126         }
 127
 128         /* If the traverse failed part-way through, we at least return
 129          * as many connections as we had already counted. If it failed
 130          * right at the start, we will return 0, which is about all we
 131          * can do anywway.
 132          */
 133
 134         return cs.curr_connections;
 135 }
 136
 137 /****************************************************************************
 138  Count the number of connections open across all shares.
 139 ****************************************************************************/
 140
 141 int count_all_current_connections(void)
 142 {
 143         return count_current_connections(NULL, True /* clear stale entries */);
 144 }
 145
 146 /****************************************************************************
 147  Claim an entry in the connections database.
 148 ****************************************************************************/
 149
 150 BOOL claim_connection(connection_struct *conn, const char *name,
 151                       uint32 msg_flags)
 152 {
 153         struct db_record *rec;
 154         struct connections_data crec;
 155         TDB_DATA dbuf;
 156         NTSTATUS status;
 157
 158         DEBUG(5,("claiming [%s]\n", name));
 159
 160         if (!(rec = connections_fetch_entry(NULL, conn, name))) {
 161                 DEBUG(0, ("connections_fetch_entry failed\n"));
 162                 return False;
 163         }
 164
 165         /* fill in the crec */
 166         ZERO_STRUCT(crec);
 167         crec.magic = 0x280267;
 168         crec.pid = procid_self();
 169         crec.cnum = conn?conn->cnum:-1;
 170         if (conn) {
 171                 crec.uid = conn->uid;
 172                 crec.gid = conn->gid;
 173                 strlcpy(crec.servicename, lp_servicename(SNUM(conn)),
 174                         sizeof(crec.servicename));
 175         }
 176         crec.start = time(NULL);
 177         crec.bcast_msg_flags = msg_flags;
 178
 179         strlcpy(crec.machine,get_remote_machine_name(),sizeof(crec.machine));
 180         strlcpy(crec.addr,conn?conn->client_address:client_addr(),
 181                 sizeof(crec.addr));
 182
 183         dbuf.dptr = (uint8 *)&crec;
 184         dbuf.dsize = sizeof(crec);
 185
 186         status = rec->store(rec, dbuf, TDB_REPLACE);
 187
 188         TALLOC_FREE(rec);
 189
 190         if (!NT_STATUS_IS_OK(status)) {
 191                 DEBUG(0,("claim_connection: tdb_store failed with error %s.\n",
 192                          nt_errstr(status)));
 193                 return False;
 194         }
 195
 196         return True;
 197 }
 198
 199 BOOL register_message_flags(BOOL doreg, uint32 msg_flags)
 200 {
 201         struct db_record *rec;
 202         struct connections_data *pcrec;
 203         NTSTATUS status;
 204
 205         DEBUG(10,("register_message_flags: %s flags 0x%x\n",
 206                 doreg ? "adding" : "removing",
 207                 (unsigned int)msg_flags ));
 208
 209         if (!(rec = connections_fetch_entry(NULL, NULL, ""))) {
 210                 DEBUG(0, ("connections_fetch_entry failed\n"));
 211                 return False;
 212         }
 213
 214         if (rec->value.dsize != sizeof(struct connections_data)) {
 215                 DEBUG(0,("register_message_flags: Got wrong record size\n"));
 216                 TALLOC_FREE(rec);
 217                 return False;
 218         }
 219
 220         pcrec = (struct connections_data *)rec->value.dptr;
 221         if (doreg)
 222                 pcrec->bcast_msg_flags |= msg_flags;
 223         else
 224                 pcrec->bcast_msg_flags &= ~msg_flags;
 225
 226         status = rec->store(rec, rec->value, TDB_REPLACE);
 227
 228         if (!NT_STATUS_IS_OK(status)) {
 229                 DEBUG(0,("register_message_flags: tdb_store failed: %s.\n",
 230                          nt_errstr(status)));
 231                 TALLOC_FREE(rec);
 232                 return False;
 233         }
 234
 235         DEBUG(10,("register_message_flags: new flags 0x%x\n",
 236                 (unsigned int)pcrec->bcast_msg_flags ));
 237
 238         TALLOC_FREE(rec);
 239
 240         return True;
 241 }
 242
 243 /*********************************************************************
 244 *********************************************************************/
 245
 246 static TDB_DATA* make_pipe_rec_key( struct pipe_open_rec *prec )
 247 {
 248         TDB_DATA *kbuf = NULL;
 249         fstring key_string;
 250
 251         if ( !prec )
 252                 return NULL;
 253
 254         if ( (kbuf = TALLOC_P(prec, TDB_DATA)) == NULL ) {
 255                 return NULL;
 256         }
 257
 258         snprintf( key_string, sizeof(key_string), "%s/%d/%d",
 259                 prec->name, procid_to_pid(&prec->pid), prec->pnum );
 260
 261         *kbuf = string_term_tdb_data(talloc_strdup(prec, key_string));
 262         if (kbuf->dptr == NULL )
 263                 return NULL;
 264
 265         return kbuf;
 266 }
 267
 268 /*********************************************************************
 269 *********************************************************************/
 270
 271 static void fill_pipe_open_rec( struct pipe_open_rec *prec, smb_np_struct *p )
 272 {
 273         prec->pid = pid_to_procid(sys_getpid());
 274         prec->pnum = p->pnum;
 275         prec->uid = geteuid();
 276         fstrcpy( prec->name, p->name );
 277
 278         return;
 279 }
 280
 281 /*********************************************************************
 282 *********************************************************************/
 283
 284 BOOL store_pipe_opendb( smb_np_struct *p )
 285 {
 286         struct db_record *dbrec;
 287         struct pipe_open_rec *prec;
 288         TDB_DATA *key;
 289         TDB_DATA data;
 290         BOOL ret = False;
 291
 292         if ( (prec = TALLOC_P( NULL, struct pipe_open_rec)) == NULL ) {
 293                 DEBUG(0,("store_pipe_opendb: talloc failed!\n"));
 294                 return False;
 295         }
 296
 297         fill_pipe_open_rec( prec, p );
 298         if ( (key = make_pipe_rec_key( prec )) == NULL ) {
 299                 goto done;
 300         }
 301
 302         data.dptr = (uint8 *)prec;
 303         data.dsize = sizeof(struct pipe_open_rec);
 304
 305         if (!(dbrec = connections_fetch_record(prec, *key))) {
 306                 DEBUG(0, ("connections_fetch_record failed\n"));
 307                 goto done;
 308         }
 309
 310         ret = NT_STATUS_IS_OK(dbrec->store(dbrec, data, TDB_REPLACE));
 311
 312 done:
 313         TALLOC_FREE( prec );
 314         return ret;
 315 }
 316
 317 /*********************************************************************
 318 *********************************************************************/
 319
 320 BOOL delete_pipe_opendb( smb_np_struct *p )
 321 {
 322         struct db_record *dbrec;
 323         struct pipe_open_rec *prec;
 324         TDB_DATA *key;
 325         BOOL ret = False;
 326
 327         if ( (prec = TALLOC_P( NULL, struct pipe_open_rec)) == NULL ) {
 328                 DEBUG(0,("store_pipe_opendb: talloc failed!\n"));
 329                 return False;
 330         }
 331
 332         fill_pipe_open_rec( prec, p );
 333         if ( (key = make_pipe_rec_key( prec )) == NULL ) {
 334                 goto done;
 335         }
 336
 337         if (!(dbrec = connections_fetch_record(prec, *key))) {
 338                 DEBUG(0, ("connections_fetch_record failed\n"));
 339                 goto done;
 340         }
 341
 342         ret = NT_STATUS_IS_OK(dbrec->delete_rec(dbrec));
 343
 344 done:
 345         TALLOC_FREE( prec );
 346         return ret;
 347 }