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 "lib/util/bitmap.h"
  26
  27 /****************************************************************************
  28  Return the number of open connections.
  29 ****************************************************************************/
  30
  31 int conn_num_open(struct smbd_server_connection *sconn)
  32 {
  33         return sconn->num_connections;
  34 }
  35
  36 /****************************************************************************
  37  Check if a snum is in use.
  38 ****************************************************************************/
  39
  40 bool conn_snum_used(struct smbd_server_connection *sconn,
  41                     int snum)
  42 {
  43         struct connection_struct *conn;
  44
  45         for (conn=sconn->connections; conn; conn=conn->next) {
  46                 if (conn->params->service == snum) {
  47                         return true;
  48                 }
  49         }
  50
  51         return false;
  52 }
  53
  54 /****************************************************************************
  55  Find first available connection slot, starting from a random position.
  56  The randomisation stops problems with the server dieing and clients
  57  thinking the server is still available.
  58 ****************************************************************************/
  59
  60 connection_struct *conn_new(struct smbd_server_connection *sconn)
  61 {
  62         connection_struct *conn;
  63
  64         if (!(conn=talloc_zero(NULL, connection_struct)) ||
  65             !(conn->params = talloc(conn, struct share_params)) ||
  66             !(conn->connectpath = talloc_strdup(conn, "")) ||
  67             !(conn->origpath = talloc_strdup(conn, ""))) {
  68                 DEBUG(0,("TALLOC_ZERO() failed!\n"));
  69                 TALLOC_FREE(conn);
  70                 return NULL;
  71         }
  72         conn->sconn = sconn;
  73         conn->force_group_gid = (gid_t)-1;
  74
  75         DLIST_ADD(sconn->connections, conn);
  76         sconn->num_connections++;
  77
  78         return conn;
  79 }
  80
  81 /****************************************************************************
  82  Clear a vuid out of the connection's vuid cache
  83 ****************************************************************************/
  84
  85 static void conn_clear_vuid_cache(connection_struct *conn, uint64_t vuid)
  86 {
  87         int i;
  88
  89         for (i=0; i<VUID_CACHE_SIZE; i++) {
  90                 struct vuid_cache_entry *ent;
  91
  92                 ent = &conn->vuid_cache.array[i];
  93
  94                 if (ent->vuid == vuid) {
  95                         ent->vuid = UID_FIELD_INVALID;
  96                         /*
  97                          * We need to keep conn->session_info around
  98                          * if it's equal to ent->session_info as a SMBulogoff
  99                          * is often followed by a SMBtdis (with an invalid
 100                          * vuid). The debug code (or regular code in
 101                          * vfs_full_audit) wants to refer to the
 102                          * conn->session_info pointer to print debug
 103                          * statements. Theoretically this is a bug,
 104                          * as once the vuid is gone the session_info
 105                          * on the conn struct isn't valid any more,
 106                          * but there's enough code that assumes
 107                          * conn->session_info is never null that
 108                          * it's easier to hold onto the old pointer
 109                          * until we get a new sessionsetupX.
 110                          * As everything is hung off the
 111                          * conn pointer as a talloc context we're not
 112                          * leaking memory here. See bug #6315. JRA.
 113                          */
 114                         if (conn->session_info == ent->session_info) {
 115                                 ent->session_info = NULL;
 116                         } else {
 117                                 TALLOC_FREE(ent->session_info);
 118                         }
 119                         ent->read_only = False;
 120                 }
 121         }
 122 }
 123
 124 /****************************************************************************
 125  Clear a vuid out of the validity cache, and as the 'owner' of a connection.
 126
 127  Called from invalidate_vuid()
 128 ****************************************************************************/
 129
 130 void conn_clear_vuid_caches(struct smbd_server_connection *sconn, uint64_t vuid)
 131 {
 132         connection_struct *conn;
 133
 134         for (conn=sconn->connections; conn;conn=conn->next) {
 135                 if (conn->vuid == vuid) {
 136                         conn->vuid = UID_FIELD_INVALID;
 137                 }
 138                 conn_clear_vuid_cache(conn, vuid);
 139         }
 140 }
 141
 142 /****************************************************************************
 143  Free a conn structure - internal part.
 144 ****************************************************************************/
 145
 146 static void conn_free_internal(connection_struct *conn)
 147 {
 148         vfs_handle_struct *handle = NULL, *thandle = NULL;
 149         struct trans_state *state = NULL;
 150
 151         /* Free vfs_connection_struct */
 152         handle = conn->vfs_handles;
 153         while(handle) {
 154                 thandle = handle->next;
 155                 DLIST_REMOVE(conn->vfs_handles, handle);
 156                 if (handle->free_data)
 157                         handle->free_data(&handle->data);
 158                 handle = thandle;
 159         }
 160
 161         /* Free any pending transactions stored on this conn. */
 162         for (state = conn->pending_trans; state; state = state->next) {
 163                 /* state->setup is a talloc child of state. */
 164                 SAFE_FREE(state->param);
 165                 SAFE_FREE(state->data);
 166         }
 167
 168         free_namearray(conn->veto_list);
 169         free_namearray(conn->hide_list);
 170         free_namearray(conn->veto_oplock_list);
 171         free_namearray(conn->aio_write_behind_list);
 172
 173         ZERO_STRUCTP(conn);
 174         talloc_destroy(conn);
 175 }
 176
 177 /****************************************************************************
 178  Free a conn structure.
 179 ****************************************************************************/
 180
 181 void conn_free(connection_struct *conn)
 182 {
 183         if (conn->sconn == NULL) {
 184                 conn_free_internal(conn);
 185                 return;
 186         }
 187
 188         DLIST_REMOVE(conn->sconn->connections, conn);
 189         SMB_ASSERT(conn->sconn->num_connections > 0);
 190         conn->sconn->num_connections--;
 191
 192         conn_free_internal(conn);
 193 }