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 static void conn_free_internal(connection_struct *conn);
  28
  29 /****************************************************************************
  30  * Remove a conn struct from conn->sconn->connections
  31  * if not already done.
  32 ****************************************************************************/
  33
  34 static int conn_struct_destructor(connection_struct *conn)
  35 {
  36         if (conn->sconn != NULL) {
  37                 DLIST_REMOVE(conn->sconn->connections, conn);
  38                 SMB_ASSERT(conn->sconn->num_connections > 0);
  39                 conn->sconn->num_connections--;
  40                 conn->sconn = NULL;
  41         }
  42         conn_free_internal(conn);
  43         return 0;
  44 }
  45
  46 /****************************************************************************
  47  Return the number of open connections.
  48 ****************************************************************************/
  49
  50 int conn_num_open(struct smbd_server_connection *sconn)
  51 {
  52         return sconn->num_connections;
  53 }
  54
  55 /****************************************************************************
  56  Check if a snum is in use.
  57 ****************************************************************************/
  58
  59 bool conn_snum_used(struct smbd_server_connection *sconn,
  60                     int snum)
  61 {
  62         struct connection_struct *conn;
  63
  64         for (conn=sconn->connections; conn; conn=conn->next) {
  65                 if (conn->params->service == snum) {
  66                         return true;
  67                 }
  68         }
  69
  70         return false;
  71 }
  72
  73 /****************************************************************************
  74  Find first available connection slot, starting from a random position.
  75  The randomisation stops problems with the server dying and clients
  76  thinking the server is still available.
  77 ****************************************************************************/
  78
  79 connection_struct *conn_new(struct smbd_server_connection *sconn)
  80 {
  81         connection_struct *conn = NULL;
  82
  83         conn = talloc_zero(NULL, connection_struct);
  84         if (conn == NULL) {
  85                 DBG_ERR("talloc_zero failed\n");
  86                 return NULL;
  87         }
  88         conn->params = talloc(conn, struct share_params);
  89         if (conn->params == NULL) {
  90                 DBG_ERR("talloc_zero failed\n");
  91                 TALLOC_FREE(conn);
  92                 return NULL;
  93         }
  94         conn->vuid_cache = talloc_zero(conn, struct vuid_cache);
  95         if (conn->vuid_cache == NULL) {
  96                 DBG_ERR("talloc_zero failed\n");
  97                 TALLOC_FREE(conn);
  98                 return NULL;
  99         }
 100         conn->connectpath = talloc_strdup(conn, "");
 101         if (conn->connectpath == NULL) {
 102                 DBG_ERR("talloc_zero failed\n");
 103                 TALLOC_FREE(conn);
 104                 return NULL;
 105         }
 106         conn->cwd_fsp = talloc_zero(conn, struct files_struct);
 107         if (conn->cwd_fsp == NULL) {
 108                 DBG_ERR("talloc_zero failed\n");
 109                 TALLOC_FREE(conn);
 110                 return NULL;
 111         }
 112         conn->cwd_fsp->fsp_name = synthetic_smb_fname(conn->cwd_fsp,
 113                                                       ".",
 114                                                       NULL,
 115                                                       NULL,
 116                                                       0,
 117                                                       0);
 118         if (conn->cwd_fsp->fsp_name == NULL) {
 119                 TALLOC_FREE(conn);
 120                 return NULL;
 121         }
 122         conn->cwd_fsp->fh = fd_handle_create(conn->cwd_fsp);
 123         if (conn->cwd_fsp->fh == NULL) {
 124                 DBG_ERR("talloc_zero failed\n");
 125                 TALLOC_FREE(conn);
 126                 return NULL;
 127         }
 128         conn->sconn = sconn;
 129         conn->force_group_gid = (gid_t)-1;
 130         fsp_set_fd(conn->cwd_fsp, -1);
 131         conn->cwd_fsp->fnum = FNUM_FIELD_INVALID;
 132         conn->cwd_fsp->conn = conn;
 133
 134         DLIST_ADD(sconn->connections, conn);
 135         sconn->num_connections++;
 136
 137         /*
 138          * Catches the case where someone forgets to call
 139          * conn_free().
 140          */
 141         talloc_set_destructor(conn, conn_struct_destructor);
 142         return conn;
 143 }
 144
 145 /****************************************************************************
 146  Clear a vuid out of the connection's vuid cache
 147 ****************************************************************************/
 148
 149 static void conn_clear_vuid_cache(connection_struct *conn, uint64_t vuid)
 150 {
 151         int i;
 152
 153         for (i=0; i<VUID_CACHE_SIZE; i++) {
 154                 struct vuid_cache_entry *ent;
 155
 156                 ent = &conn->vuid_cache->array[i];
 157
 158                 if (ent->vuid == vuid) {
 159                         ent->vuid = UID_FIELD_INVALID;
 160                         /*
 161                          * We need to keep conn->session_info around
 162                          * if it's equal to ent->session_info as a SMBulogoff
 163                          * is often followed by a SMBtdis (with an invalid
 164                          * vuid). The debug code (or regular code in
 165                          * vfs_full_audit) wants to refer to the
 166                          * conn->session_info pointer to print debug
 167                          * statements. Theoretically this is a bug,
 168                          * as once the vuid is gone the session_info
 169                          * on the conn struct isn't valid any more,
 170                          * but there's enough code that assumes
 171                          * conn->session_info is never null that
 172                          * it's easier to hold onto the old pointer
 173                          * until we get a new sessionsetupX.
 174                          * As everything is hung off the
 175                          * conn pointer as a talloc context we're not
 176                          * leaking memory here. See bug #6315. JRA.
 177                          */
 178                         if (conn->session_info == ent->session_info) {
 179                                 ent->session_info = NULL;
 180                         } else {
 181                                 TALLOC_FREE(ent->session_info);
 182                         }
 183                         ent->read_only = False;
 184                         ent->share_access = 0;
 185                 }
 186         }
 187 }
 188
 189 /****************************************************************************
 190  Clear a vuid out of the validity cache, and as the 'owner' of a connection.
 191
 192  Called from invalidate_vuid()
 193 ****************************************************************************/
 194
 195 void conn_clear_vuid_caches(struct smbd_server_connection *sconn, uint64_t vuid)
 196 {
 197         connection_struct *conn;
 198
 199         for (conn=sconn->connections; conn;conn=conn->next) {
 200                 if (conn->vuid == vuid) {
 201                         conn->vuid = UID_FIELD_INVALID;
 202                 }
 203                 conn_clear_vuid_cache(conn, vuid);
 204         }
 205 }
 206
 207 /****************************************************************************
 208  Free a conn structure - internal part.
 209 ****************************************************************************/
 210
 211 static void conn_free_internal(connection_struct *conn)
 212 {
 213         vfs_handle_struct *handle = NULL, *thandle = NULL;
 214         struct trans_state *state = NULL;
 215
 216         /* Free vfs_connection_struct */
 217         handle = conn->vfs_handles;
 218         while(handle) {
 219                 thandle = handle->next;
 220                 DLIST_REMOVE(conn->vfs_handles, handle);
 221                 if (handle->free_data)
 222                         handle->free_data(&handle->data);
 223                 handle = thandle;
 224         }
 225
 226         /* Free any pending transactions stored on this conn. */
 227         for (state = conn->pending_trans; state; state = state->next) {
 228                 /* state->setup is a talloc child of state. */
 229                 SAFE_FREE(state->param);
 230                 SAFE_FREE(state->data);
 231         }
 232
 233         free_namearray(conn->veto_list);
 234         free_namearray(conn->hide_list);
 235         free_namearray(conn->veto_oplock_list);
 236         free_namearray(conn->aio_write_behind_list);
 237
 238         ZERO_STRUCTP(conn);
 239 }
 240
 241 /****************************************************************************
 242  Free a conn structure.
 243 ****************************************************************************/
 244
 245 void conn_free(connection_struct *conn)
 246 {
 247         TALLOC_FREE(conn);
 248 }
 249
 250 /*
 251  * Correctly initialize a share with case options.
 252  */
 253 void conn_setup_case_options(connection_struct *conn)
 254 {
 255         int snum = conn->params->service;
 256
 257         if (lp_case_sensitive(snum) == Auto) {
 258                 /* We will be setting this per packet. Set to be case
 259                 * insensitive for now. */
 260                 conn->case_sensitive = false;
 261         } else {
 262                 conn->case_sensitive = (bool)lp_case_sensitive(snum);
 263         }
 264
 265         conn->case_preserve = lp_preserve_case(snum);
 266         conn->short_case_preserve = lp_short_preserve_case(snum);
 267 }