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->vuid_cache = talloc_zero(conn, struct vuid_cache)) ||
  67             !(conn->connectpath = talloc_strdup(conn, "")) ||
  68             !(conn->origpath = talloc_strdup(conn, ""))) {
  69                 DEBUG(0,("TALLOC_ZERO() failed!\n"));
  70                 TALLOC_FREE(conn);
  71                 return NULL;
  72         }
  73         conn->sconn = sconn;
  74         conn->force_group_gid = (gid_t)-1;
  75
  76         DLIST_ADD(sconn->connections, conn);
  77         sconn->num_connections++;
  78
  79         return conn;
  80 }
  81
  82 /****************************************************************************
  83  Clear a vuid out of the connection's vuid cache
  84 ****************************************************************************/
  85
  86 static void conn_clear_vuid_cache(connection_struct *conn, uint64_t vuid)
  87 {
  88         int i;
  89
  90         for (i=0; i<VUID_CACHE_SIZE; i++) {
  91                 struct vuid_cache_entry *ent;
  92
  93                 ent = &conn->vuid_cache->array[i];
  94
  95                 if (ent->vuid == vuid) {
  96                         ent->vuid = UID_FIELD_INVALID;
  97                         /*
  98                          * We need to keep conn->session_info around
  99                          * if it's equal to ent->session_info as a SMBulogoff
 100                          * is often followed by a SMBtdis (with an invalid
 101                          * vuid). The debug code (or regular code in
 102                          * vfs_full_audit) wants to refer to the
 103                          * conn->session_info pointer to print debug
 104                          * statements. Theoretically this is a bug,
 105                          * as once the vuid is gone the session_info
 106                          * on the conn struct isn't valid any more,
 107                          * but there's enough code that assumes
 108                          * conn->session_info is never null that
 109                          * it's easier to hold onto the old pointer
 110                          * until we get a new sessionsetupX.
 111                          * As everything is hung off the
 112                          * conn pointer as a talloc context we're not
 113                          * leaking memory here. See bug #6315. JRA.
 114                          */
 115                         if (conn->session_info == ent->session_info) {
 116                                 ent->session_info = NULL;
 117                         } else {
 118                                 TALLOC_FREE(ent->session_info);
 119                         }
 120                         ent->read_only = False;
 121                         ent->share_access = 0;
 122                 }
 123         }
 124 }
 125
 126 /****************************************************************************
 127  Clear a vuid out of the validity cache, and as the 'owner' of a connection.
 128
 129  Called from invalidate_vuid()
 130 ****************************************************************************/
 131
 132 void conn_clear_vuid_caches(struct smbd_server_connection *sconn, uint64_t vuid)
 133 {
 134         connection_struct *conn;
 135
 136         for (conn=sconn->connections; conn;conn=conn->next) {
 137                 if (conn->vuid == vuid) {
 138                         conn->vuid = UID_FIELD_INVALID;
 139                 }
 140                 conn_clear_vuid_cache(conn, vuid);
 141         }
 142 }
 143
 144 /****************************************************************************
 145  Free a conn structure - internal part.
 146 ****************************************************************************/
 147
 148 static void conn_free_internal(connection_struct *conn)
 149 {
 150         vfs_handle_struct *handle = NULL, *thandle = NULL;
 151         struct trans_state *state = NULL;
 152
 153         /* Free vfs_connection_struct */
 154         handle = conn->vfs_handles;
 155         while(handle) {
 156                 thandle = handle->next;
 157                 DLIST_REMOVE(conn->vfs_handles, handle);
 158                 if (handle->free_data)
 159                         handle->free_data(&handle->data);
 160                 handle = thandle;
 161         }
 162
 163         /* Free any pending transactions stored on this conn. */
 164         for (state = conn->pending_trans; state; state = state->next) {
 165                 /* state->setup is a talloc child of state. */
 166                 SAFE_FREE(state->param);
 167                 SAFE_FREE(state->data);
 168         }
 169
 170         free_namearray(conn->veto_list);
 171         free_namearray(conn->hide_list);
 172         free_namearray(conn->veto_oplock_list);
 173         free_namearray(conn->aio_write_behind_list);
 174
 175         ZERO_STRUCTP(conn);
 176         talloc_destroy(conn);
 177 }
 178
 179 /****************************************************************************
 180  Free a conn structure.
 181 ****************************************************************************/
 182
 183 void conn_free(connection_struct *conn)
 184 {
 185         if (conn->sconn == NULL) {
 186                 conn_free_internal(conn);
 187                 return;
 188         }
 189
 190         DLIST_REMOVE(conn->sconn->connections, conn);
 191         SMB_ASSERT(conn->sconn->num_connections > 0);
 192         conn->sconn->num_connections--;
 193
 194         conn_free_internal(conn);
 195 }