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 "nsswitch/winbind_client.h"
  27 #include "passdb.h"
  28
  29 #undef DBGC_CLASS
  30 #define DBGC_CLASS DBGC_AUTH
  31
  32
  33 /***************************************************************************
  34  Is the incoming username our own machine account ?
  35  If so, the connection is almost certainly from winbindd.
  36 ***************************************************************************/
  37
  38 static bool is_our_machine_account(const char *username)
  39 {
  40         bool ret;
  41         char *truncname = NULL;
  42         size_t ulen = strlen(username);
  43
  44         if (ulen == 0 || username[ulen-1] != '$') {
  45                 return false;
  46         }
  47         truncname = SMB_STRDUP(username);
  48         if (!truncname) {
  49                 return false;
  50         }
  51         truncname[ulen-1] = '\0';
  52         ret = strequal(truncname, lp_netbios_name());
  53         SAFE_FREE(truncname);
  54         return ret;
  55 }
  56
  57 /***************************************************************************
  58  Make (and fill) a user_info struct from a struct samu
  59 ***************************************************************************/
  60
  61 NTSTATUS make_server_info_sam(TALLOC_CTX *mem_ctx,
  62                               struct samu *sampass,
  63                               struct auth_serversupplied_info **pserver_info)
  64 {
  65         struct passwd *pwd;
  66         struct auth_serversupplied_info *server_info;
  67         const char *username = pdb_get_username(sampass);
  68         TALLOC_CTX *tmp_ctx;
  69         NTSTATUS status;
  70
  71         tmp_ctx = talloc_stackframe();
  72         if (tmp_ctx == NULL) {
  73                 return NT_STATUS_NO_MEMORY;
  74         }
  75
  76         server_info = make_server_info(tmp_ctx);
  77         if (server_info == NULL) {
  78                 return NT_STATUS_NO_MEMORY;
  79         }
  80
  81         pwd = Get_Pwnam_alloc(tmp_ctx, username);
  82         if (pwd == NULL) {
  83                 DEBUG(1, ("User %s in passdb, but getpwnam() fails!\n",
  84                           pdb_get_username(sampass)));
  85                 status = NT_STATUS_NO_SUCH_USER;
  86                 goto out;
  87         }
  88
  89         status = samu_to_SamInfo3(server_info,
  90                                   sampass,
  91                                   lp_netbios_name(),
  92                                   &server_info->info3,
  93                                   &server_info->extra);
  94         if (!NT_STATUS_IS_OK(status)) {
  95                 goto out;
  96         }
  97
  98         server_info->unix_name = talloc_strdup(server_info, pwd->pw_name);
  99         if (server_info->unix_name == NULL) {
 100                 status = NT_STATUS_NO_MEMORY;
 101                 goto out;
 102         }
 103
 104         server_info->utok.gid = pwd->pw_gid;
 105         server_info->utok.uid = pwd->pw_uid;
 106
 107         if (IS_DC && is_our_machine_account(username)) {
 108                 /*
 109                  * This is a hack of monstrous proportions.
 110                  * If we know it's winbindd talking to us,
 111                  * we know we must never recurse into it,
 112                  * so turn off contacting winbindd for this
 113                  * entire process. This will get fixed when
 114                  * winbindd doesn't need to talk to smbd on
 115                  * a PDC. JRA.
 116                  */
 117
 118                 (void)winbind_off();
 119
 120                 DEBUG(10, ("make_server_info_sam: our machine account %s "
 121                            "turning off winbindd requests.\n", username));
 122         }
 123
 124         DEBUG(5,("make_server_info_sam: made server info for user %s -> %s\n",
 125                  pdb_get_username(sampass), server_info->unix_name));
 126
 127         *pserver_info = talloc_steal(mem_ctx, server_info);
 128
 129         status = NT_STATUS_OK;
 130 out:
 131         talloc_free(tmp_ctx);
 132
 133         return status;
 134 }