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
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22 #include "includes.h"
  23
  24 /* set these to define the limits of the server. NOTE These are on a
  25    per-client basis. Thus any one machine can't connect to more than
  26    MAX_CONNECTIONS services, but any number of machines may connect at
  27    one time. */
  28 #define MAX_CONNECTIONS 128
  29
  30 static connection_struct *Connections;
  31
  32 /* number of open connections */
  33 static struct bitmap *bmap;
  34 static int num_open;
  35
  36 /****************************************************************************
  37 init the conn structures
  38 ****************************************************************************/
  39 void conn_init(void)
  40 {
  41         bmap = bitmap_allocate(MAX_CONNECTIONS);
  42 }
  43
  44 /****************************************************************************
  45 return the number of open connections
  46 ****************************************************************************/
  47 int conn_num_open(void)
  48 {
  49         return num_open;
  50 }
  51
  52
  53 /****************************************************************************
  54 check if a snum is in use
  55 ****************************************************************************/
  56 BOOL conn_snum_used(int snum)
  57 {
  58         connection_struct *conn;
  59         for (conn=Connections;conn;conn=conn->next) {
  60                 if (conn->service == snum) {
  61                         return(True);
  62                 }
  63         }
  64         return(False);
  65 }
  66
  67
  68 /****************************************************************************
  69 find a conn given a cnum
  70 ****************************************************************************/
  71 connection_struct *conn_find(int cnum)
  72 {
  73         int count=0;
  74         connection_struct *conn;
  75
  76         for (conn=Connections;conn;conn=conn->next,count++) {
  77                 if (conn->cnum == cnum) {
  78                         if (count > 10) {
  79                                 DLIST_PROMOTE(Connections, conn);
  80                         }
  81                         return conn;
  82                 }
  83         }
  84
  85         return NULL;
  86 }
  87
  88
  89 /****************************************************************************
  90   find first available connection slot, starting from a random position.
  91 The randomisation stops problems with the server dieing and clients
  92 thinking the server is still available.
  93 ****************************************************************************/
  94 connection_struct *conn_new(void)
  95 {
  96         connection_struct *conn;
  97         int i;
  98
  99         i = bitmap_find(bmap, 1);
 100
 101         if (i == -1) {
 102                 DEBUG(1,("ERROR! Out of connection structures\n"));
 103                 return NULL;
 104         }
 105
 106         conn = (connection_struct *)malloc(sizeof(*conn));
 107         if (!conn) return NULL;
 108
 109         ZERO_STRUCTP(conn);
 110         conn->cnum = i;
 111
 112         bitmap_set(bmap, i);
 113
 114         num_open++;
 115
 116         string_set(&conn->user,"");
 117         string_set(&conn->dirpath,"");
 118         string_set(&conn->connectpath,"");
 119         string_set(&conn->origpath,"");
 120
 121         DLIST_ADD(Connections, conn);
 122
 123         return conn;
 124 }
 125
 126 /****************************************************************************
 127 close all conn structures
 128 ****************************************************************************/
 129 void conn_close_all(void)
 130 {
 131         connection_struct *conn, *next;
 132         for (conn=Connections;conn;conn=next) {
 133                 next=conn->next;
 134                 close_cnum(conn, conn->vuid);
 135         }
 136 }
 137
 138 /****************************************************************************
 139 idle inactive connections
 140 ****************************************************************************/
 141 BOOL conn_idle_all(time_t t, int deadtime)
 142 {
 143         BOOL allidle = True;
 144         connection_struct *conn, *next;
 145
 146         for (conn=Connections;conn;conn=next) {
 147                 next=conn->next;
 148                 /* close dirptrs on connections that are idle */
 149                 if ((t-conn->lastused) > DPTR_IDLE_TIMEOUT)
 150                         dptr_idlecnum(conn);
 151
 152                 if (conn->num_files_open > 0 ||
 153                     (t-conn->lastused)<deadtime)
 154                         allidle = False;
 155         }
 156
 157         return allidle;
 158 }
 159
 160 /****************************************************************************
 161 clear a vuid out of the validity cache, and as the 'owner' of a connection.
 162 ****************************************************************************/
 163 void conn_clear_vuid_cache(uint16 vuid)
 164 {
 165         connection_struct *conn;
 166         int i;
 167
 168         for (conn=Connections;conn;conn=conn->next) {
 169                 if (conn->vuid == vuid) {
 170                         conn->vuid = UID_FIELD_INVALID;
 171                 }
 172
 173                 for (i=0;i<conn->vuid_cache.entries && i< VUID_CACHE_SIZE;i++) {
 174                         if (conn->vuid_cache.list[i] == vuid) {
 175                                 conn->vuid_cache.list[i] = UID_FIELD_INVALID;
 176                         }
 177                 }
 178         }
 179 }
 180
 181 /****************************************************************************
 182  Free a conn structure.
 183 ****************************************************************************/
 184
 185 void conn_free(connection_struct *conn)
 186 {
 187         smb_vfs_handle_struct *handle, *thandle;
 188         void (*done_fptr)(connection_struct *the_conn);
 189
 190         /* Free vfs_connection_struct */
 191         handle = conn->vfs_private;
 192         while(handle) {
 193                 /* Close dlopen() handle */
 194                 done_fptr = (void (*)(connection_struct *))sys_dlsym(handle->handle, "vfs_done");
 195
 196                 if (done_fptr == NULL) {
 197                         DEBUG(3, ("No vfs_done() symbol found in module with handle %p, ignoring\n", handle->handle));
 198                 } else {
 199                         done_fptr(conn);
 200                 }
 201                 sys_dlclose(handle->handle);
 202                 DLIST_REMOVE(conn->vfs_private, handle);
 203                 thandle = handle->next;
 204                 SAFE_FREE(handle);
 205                 handle = thandle;
 206         }
 207
 208         DLIST_REMOVE(Connections, conn);
 209
 210         if (conn->ngroups && conn->groups) {
 211                 SAFE_FREE(conn->groups);
 212                 conn->ngroups = 0;
 213         }
 214
 215         free_namearray(conn->veto_list);
 216         free_namearray(conn->hide_list);
 217         free_namearray(conn->veto_oplock_list);
 218
 219         string_free(&conn->user);
 220         string_free(&conn->dirpath);
 221         string_free(&conn->connectpath);
 222         string_free(&conn->origpath);
 223
 224         bitmap_clear(bmap, conn->cnum);
 225         num_open--;
 226
 227         ZERO_STRUCTP(conn);
 228         SAFE_FREE(conn);
 229 }
 230
 231
 232 /****************************************************************************
 233 receive a smbcontrol message to forcibly unmount a share
 234 the message contains just a share name and all instances of that
 235 share are unmounted
 236 the special sharename '*' forces unmount of all shares
 237 ****************************************************************************/
 238 void msg_force_tdis(int msg_type, pid_t pid, void *buf, size_t len)
 239 {
 240         connection_struct *conn, *next;
 241         fstring sharename;
 242
 243         fstrcpy(sharename, buf);
 244
 245         if (strcmp(sharename, "*") == 0) {
 246                 DEBUG(1,("Forcing close of all shares\n"));
 247                 conn_close_all();
 248                 return;
 249         }
 250
 251         for (conn=Connections;conn;conn=next) {
 252                 next=conn->next;
 253                 if (strequal(lp_servicename(conn->service), sharename)) {
 254                         DEBUG(1,("Forcing close of share %s cnum=%d\n",
 255                                  sharename, conn->cnum));
 256                         close_cnum(conn, (uint16)-1);
 257                 }
 258         }
 259 }