source3/smbd/conn.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    Version 1.9.
   4    Manage connections_struct structures
   5    Copyright (C) Andrew Tridgell 1998
   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 extern int DEBUGLEVEL;
  25
  26 /* set these to define the limits of the server. NOTE These are on a
  27    per-client basis. Thus any one machine can't connect to more than
  28    MAX_CONNECTIONS services, but any number of machines may connect at
  29    one time. */
  30 #define MAX_CONNECTIONS 128
  31
  32 static connection_struct *Connections;
  33
  34 /* number of open connections */
  35 static struct bitmap *bmap;
  36 static int num_open;
  37
  38 /****************************************************************************
  39 init the conn structures
  40 ****************************************************************************/
  41 void conn_init(void)
  42 {
  43         bmap = bitmap_allocate(MAX_CONNECTIONS);
  44 }
  45
  46 /****************************************************************************
  47 return the number of open connections
  48 ****************************************************************************/
  49 int conn_num_open(void)
  50 {
  51         return num_open;
  52 }
  53
  54
  55 /****************************************************************************
  56 check if a snum is in use
  57 ****************************************************************************/
  58 BOOL conn_snum_used(int snum)
  59 {
  60         connection_struct *conn;
  61         for (conn=Connections;conn;conn=conn->next) {
  62                 if (conn->service == snum) {
  63                         return(True);
  64                 }
  65         }
  66         return(False);
  67 }
  68
  69
  70 /****************************************************************************
  71 find a conn given a cnum
  72 ****************************************************************************/
  73 connection_struct *conn_find(int cnum)
  74 {
  75         int count=0;
  76         connection_struct *conn;
  77
  78         for (conn=Connections;conn;conn=conn->next,count++) {
  79                 if (conn->cnum == cnum) {
  80                         if (count > 10) {
  81                                 DLIST_PROMOTE(Connections, conn);
  82                         }
  83                         return conn;
  84                 }
  85         }
  86
  87         return NULL;
  88 }
  89
  90
  91 /****************************************************************************
  92   find first available connection slot, starting from a random position.
  93 The randomisation stops problems with the server dieing and clients
  94 thinking the server is still available.
  95 ****************************************************************************/
  96 connection_struct *conn_new(void)
  97 {
  98         connection_struct *conn;
  99         int i;
 100
 101         i = bitmap_find(bmap, 1);
 102
 103         if (i == -1) {
 104                 DEBUG(1,("ERROR! Out of connection structures\n"));
 105                 return NULL;
 106         }
 107
 108         conn = (connection_struct *)malloc(sizeof(*conn));
 109         if (!conn) return NULL;
 110
 111         ZERO_STRUCTP(conn);
 112         conn->cnum = i;
 113
 114         bitmap_set(bmap, i);
 115
 116         num_open++;
 117
 118         string_set(&conn->user,"");
 119         string_set(&conn->dirpath,"");
 120         string_set(&conn->connectpath,"");
 121         string_set(&conn->origpath,"");
 122
 123         DLIST_ADD(Connections, conn);
 124
 125         return conn;
 126 }
 127
 128 /****************************************************************************
 129 close all conn structures
 130 ****************************************************************************/
 131 void conn_close_all(void)
 132 {
 133         connection_struct *conn, *next;
 134         for (conn=Connections;conn;conn=next) {
 135                 next=conn->next;
 136                 close_cnum(conn, (uint16)-1);
 137         }
 138 }
 139
 140 /****************************************************************************
 141 idle inactive connections
 142 ****************************************************************************/
 143 BOOL conn_idle_all(time_t t, int deadtime)
 144 {
 145         BOOL allidle = True;
 146         connection_struct *conn, *next;
 147
 148         for (conn=Connections;conn;conn=next) {
 149                 next=conn->next;
 150                 /* close dirptrs on connections that are idle */
 151                 if ((t-conn->lastused) > DPTR_IDLE_TIMEOUT)
 152                         dptr_idlecnum(conn);
 153
 154                 if (conn->num_files_open > 0 ||
 155                     (t-conn->lastused)<deadtime)
 156                         allidle = False;
 157         }
 158
 159         return allidle;
 160 }
 161
 162 /****************************************************************************
 163  Free a conn structure.
 164 ****************************************************************************/
 165
 166 void conn_free(connection_struct *conn)
 167 {
 168         /* Free vfs_connection_struct */
 169
 170 #ifdef HAVE_LIBDL
 171         if (conn->dl_handle != NULL) {
 172                 /* Close dlopen() handle */
 173                 dlclose(conn->dl_handle);
 174         }
 175 #endif /* HAVE_LIBDL */
 176
 177         DLIST_REMOVE(Connections, conn);
 178
 179         if (conn->ngroups && conn->groups) {
 180                 SAFE_FREE(conn->groups);
 181                 conn->ngroups = 0;
 182         }
 183
 184         delete_nt_token(&conn->nt_user_token);
 185         free_namearray(conn->veto_list);
 186         free_namearray(conn->hide_list);
 187         free_namearray(conn->veto_oplock_list);
 188
 189         string_free(&conn->user);
 190         string_free(&conn->dirpath);
 191         string_free(&conn->connectpath);
 192         string_free(&conn->origpath);
 193
 194         bitmap_clear(bmap, conn->cnum);
 195         num_open--;
 196
 197         ZERO_STRUCTP(conn);
 198         SAFE_FREE(conn);
 199 }
 200
 201
 202 /****************************************************************************
 203 receive a smbcontrol message to forcibly unmount a share
 204 the message contains just a share name and all instances of that
 205 share are unmounted
 206 the special sharename '*' forces unmount of all shares
 207 ****************************************************************************/
 208 void msg_force_tdis(int msg_type, pid_t pid, void *buf, size_t len)
 209 {
 210         connection_struct *conn, *next;
 211         fstring sharename;
 212
 213         fstrcpy(sharename, buf);
 214
 215         if (strcmp(sharename, "*") == 0) {
 216                 DEBUG(1,("Forcing close of all shares\n"));
 217                 conn_close_all();
 218                 return;
 219         }
 220
 221         for (conn=Connections;conn;conn=next) {
 222                 next=conn->next;
 223                 if (strequal(lp_servicename(conn->service), sharename)) {
 224                         DEBUG(1,("Forcing close of share %s cnum=%d\n",
 225                                  sharename, conn->cnum));
 226                         close_cnum(conn, (uint16)-1);
 227                 }
 228         }
 229 }