source3/auth/server_info_sam.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Authentication utility functions
   4    Copyright (C) Andrew Tridgell 1992-1998
   5    Copyright (C) Andrew Bartlett 2001
   6    Copyright (C) Jeremy Allison 2000-2001
   7    Copyright (C) Rafal Szczesniak 2002
   8    Copyright (C) Volker Lendecke 2006
   9
  10    This program is free software; you can redistribute it and/or modify
  11    it under the terms of the GNU General Public License as published by
  12    the Free Software Foundation; either version 3 of the License, or
  13    (at your option) any later version.
  14
  15    This program is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18    GNU General Public License for more details.
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  22 */
  23
  24 #include "includes.h"
  25 #include "auth.h"
  26 #include "smbd/globals.h"
  27 #include "../libcli/auth/libcli_auth.h"
  28 #include "nsswitch/winbind_client.h"
  29 #include "passdb.h"
  30
  31 #undef DBGC_CLASS
  32 #define DBGC_CLASS DBGC_AUTH
  33
  34
  35 /***************************************************************************
  36  Is the incoming username our own machine account ?
  37  If so, the connection is almost certainly from winbindd.
  38 ***************************************************************************/
  39
  40 static bool is_our_machine_account(const char *username)
  41 {
  42         bool ret;
  43         char *truncname = NULL;
  44         size_t ulen = strlen(username);
  45
  46         if (ulen == 0 || username[ulen-1] != '$') {
  47                 return false;
  48         }
  49         truncname = SMB_STRDUP(username);
  50         if (!truncname) {
  51                 return false;
  52         }
  53         truncname[ulen-1] = '\0';
  54         ret = strequal(truncname, global_myname());
  55         SAFE_FREE(truncname);
  56         return ret;
  57 }
  58
  59 /***************************************************************************
  60  Make (and fill) a user_info struct from a struct samu
  61 ***************************************************************************/
  62
  63 NTSTATUS make_server_info_sam(struct auth_serversupplied_info **server_info,
  64                               struct samu *sampass)
  65 {
  66         struct passwd *pwd;
  67         struct auth_serversupplied_info *result;
  68         const char *username = pdb_get_username(sampass);
  69         NTSTATUS status;
  70
  71         if ( !(result = make_server_info(NULL)) ) {
  72                 return NT_STATUS_NO_MEMORY;
  73         }
  74
  75         if ( !(pwd = Get_Pwnam_alloc(result, username)) ) {
  76                 DEBUG(1, ("User %s in passdb, but getpwnam() fails!\n",
  77                           pdb_get_username(sampass)));
  78                 TALLOC_FREE(result);
  79                 return NT_STATUS_NO_SUCH_USER;
  80         }
  81
  82         status = samu_to_SamInfo3(result, sampass, global_myname(),
  83                                   &result->info3, &result->extra);
  84         if (!NT_STATUS_IS_OK(status)) {
  85                 TALLOC_FREE(result);
  86                 return status;
  87         }
  88
  89         result->unix_name = pwd->pw_name;
  90         /* Ensure that we keep pwd->pw_name, because we will free pwd below */
  91         talloc_steal(result, pwd->pw_name);
  92         result->utok.gid = pwd->pw_gid;
  93         result->utok.uid = pwd->pw_uid;
  94
  95         TALLOC_FREE(pwd);
  96
  97         result->sanitized_username = sanitize_username(result,
  98                                                        result->unix_name);
  99         if (result->sanitized_username == NULL) {
 100                 TALLOC_FREE(result);
 101                 return NT_STATUS_NO_MEMORY;
 102         }
 103
 104         if (IS_DC && is_our_machine_account(username)) {
 105                 /*
 106                  * This is a hack of monstrous proportions.
 107                  * If we know it's winbindd talking to us,
 108                  * we know we must never recurse into it,
 109                  * so turn off contacting winbindd for this
 110                  * entire process. This will get fixed when
 111                  * winbindd doesn't need to talk to smbd on
 112                  * a PDC. JRA.
 113                  */
 114
 115                 (void)winbind_off();
 116
 117                 DEBUG(10, ("make_server_info_sam: our machine account %s "
 118                            "turning off winbindd requests.\n", username));
 119         }
 120
 121         DEBUG(5,("make_server_info_sam: made server info for user %s -> %s\n",
 122                  pdb_get_username(sampass), result->unix_name));
 123
 124         *server_info = result;
 125
 126         return NT_STATUS_OK;
 127 }