source3/registry/reg_dispatcher.c

   1 /*
   2  *  Unix SMB/CIFS implementation.
   3  *  Virtual Windows Registry Layer
   4  *  Copyright (C) Gerald Carter                     2002-2005
   5  *  Copyright (C) Michael Adam                      2006-2008
   6  *
   7  *  This program is free software; you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License as published by
   9  *  the Free Software Foundation; either version 3 of the License, or
  10  *  (at your option) any later version.
  11  *
  12  *  This program is distributed in the hope that it will be useful,
  13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *  GNU General Public License for more details.
  16  *
  17  *  You should have received a copy of the GNU General Public License
  18  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 /*
  22  * Implementation of registry frontend view functions.
  23  * Functions moved from reg_frontend.c to minimize linker deps.
  24  */
  25
  26 #include "includes.h"
  27
  28 #undef DBGC_CLASS
  29 #define DBGC_CLASS DBGC_REGISTRY
  30
  31 static const struct generic_mapping reg_generic_map =
  32         { REG_KEY_READ, REG_KEY_WRITE, REG_KEY_EXECUTE, REG_KEY_ALL };
  33
  34 /********************************************************************
  35 ********************************************************************/
  36
  37 static WERROR construct_registry_sd(TALLOC_CTX *ctx, SEC_DESC **psd)
  38 {
  39         SEC_ACE ace[3];
  40         size_t i = 0;
  41         SEC_DESC *sd;
  42         SEC_ACL *theacl;
  43         size_t sd_size;
  44
  45         /* basic access for Everyone */
  46
  47         init_sec_ace(&ace[i++], &global_sid_World, SEC_ACE_TYPE_ACCESS_ALLOWED,
  48                      REG_KEY_READ, 0);
  49
  50         /* Full Access 'BUILTIN\Administrators' */
  51
  52         init_sec_ace(&ace[i++], &global_sid_Builtin_Administrators,
  53                      SEC_ACE_TYPE_ACCESS_ALLOWED, REG_KEY_ALL, 0);
  54
  55         /* Full Access 'NT Authority\System' */
  56
  57         init_sec_ace(&ace[i++], &global_sid_System, SEC_ACE_TYPE_ACCESS_ALLOWED,
  58                      REG_KEY_ALL, 0);
  59
  60         /* create the security descriptor */
  61
  62         theacl = make_sec_acl(ctx, NT4_ACL_REVISION, i, ace);
  63         if (theacl == NULL) {
  64                 return WERR_NOMEM;
  65         }
  66
  67         sd = make_sec_desc(ctx, SEC_DESC_REVISION, SEC_DESC_SELF_RELATIVE,
  68                            &global_sid_Builtin_Administrators,
  69                            &global_sid_System, NULL, theacl,
  70                            &sd_size);
  71         if (sd == NULL) {
  72                 return WERR_NOMEM;
  73         }
  74
  75         *psd = sd;
  76         return WERR_OK;
  77 }
  78
  79 /***********************************************************************
  80  High level wrapper function for storing registry subkeys
  81  ***********************************************************************/
  82
  83 bool store_reg_keys( REGISTRY_KEY *key, REGSUBKEY_CTR *subkeys )
  84 {
  85         if (key->ops && key->ops->store_subkeys)
  86                 return key->ops->store_subkeys(key->name, subkeys);
  87
  88         return false;
  89 }
  90
  91 /***********************************************************************
  92  High level wrapper function for storing registry values
  93  ***********************************************************************/
  94
  95 bool store_reg_values( REGISTRY_KEY *key, REGVAL_CTR *val )
  96 {
  97         if (key->ops && key->ops->store_values)
  98                 return key->ops->store_values(key->name, val);
  99
 100         return false;
 101 }
 102
 103 /***********************************************************************
 104  High level wrapper function for enumerating registry subkeys
 105  Initialize the TALLOC_CTX if necessary
 106  ***********************************************************************/
 107
 108 int fetch_reg_keys( REGISTRY_KEY *key, REGSUBKEY_CTR *subkey_ctr )
 109 {
 110         int result = -1;
 111
 112         if (key->ops && key->ops->fetch_subkeys)
 113                 result = key->ops->fetch_subkeys(key->name, subkey_ctr);
 114
 115         return result;
 116 }
 117
 118 /***********************************************************************
 119  High level wrapper function for enumerating registry values
 120  ***********************************************************************/
 121
 122 int fetch_reg_values( REGISTRY_KEY *key, REGVAL_CTR *val )
 123 {
 124         int result = -1;
 125
 126         DEBUG(10, ("fetch_reg_values called for key '%s' (ops %p)\n", key->name,
 127                    (key->ops) ? (void *)key->ops : NULL));
 128
 129         if (key->ops && key->ops->fetch_values)
 130                 result = key->ops->fetch_values(key->name, val);
 131
 132         return result;
 133 }
 134
 135 /***********************************************************************
 136  High level access check for passing the required access mask to the
 137  underlying registry backend
 138  ***********************************************************************/
 139
 140 bool regkey_access_check( REGISTRY_KEY *key, uint32 requested, uint32 *granted,
 141                           const struct nt_user_token *token )
 142 {
 143         SEC_DESC *sec_desc;
 144         NTSTATUS status;
 145         WERROR err;
 146         TALLOC_CTX *mem_ctx;
 147
 148         /* use the default security check if the backend has not defined its
 149          * own */
 150
 151         if (key->ops && key->ops->reg_access_check) {
 152                 return key->ops->reg_access_check(key->name, requested,
 153                                                   granted, token);
 154         }
 155
 156         /*
 157          * The secdesc routines can't yet cope with a NULL talloc ctx sanely.
 158          */
 159
 160         if (!(mem_ctx = talloc_init("regkey_access_check"))) {
 161                 return false;
 162         }
 163
 164         err = regkey_get_secdesc(mem_ctx, key, &sec_desc);
 165
 166         if (!W_ERROR_IS_OK(err)) {
 167                 TALLOC_FREE(mem_ctx);
 168                 return false;
 169         }
 170
 171         se_map_generic( &requested, &reg_generic_map );
 172
 173         status =se_access_check(sec_desc, token, requested, granted);
 174         if (!NT_STATUS_IS_OK(status)) {
 175                 TALLOC_FREE(mem_ctx);
 176                 return false;
 177         }
 178
 179         TALLOC_FREE(mem_ctx);
 180         return NT_STATUS_IS_OK(status);
 181 }
 182
 183 WERROR regkey_get_secdesc(TALLOC_CTX *mem_ctx, REGISTRY_KEY *key,
 184                           struct security_descriptor **psecdesc)
 185 {
 186         struct security_descriptor *secdesc;
 187         WERROR werr;
 188
 189         if (key->ops && key->ops->get_secdesc) {
 190                 werr = key->ops->get_secdesc(mem_ctx, key->name, psecdesc);
 191                 if (W_ERROR_IS_OK(werr)) {
 192                         return WERR_OK;
 193                 }
 194         }
 195
 196         werr = construct_registry_sd(mem_ctx, &secdesc);
 197         if (!W_ERROR_IS_OK(werr)) {
 198                 return werr;
 199         }
 200
 201         *psecdesc = secdesc;
 202         return WERR_OK;
 203 }
 204
 205 WERROR regkey_set_secdesc(REGISTRY_KEY *key,
 206                           struct security_descriptor *psecdesc)
 207 {
 208         if (key->ops && key->ops->set_secdesc) {
 209                 return key->ops->set_secdesc(key->name, psecdesc);
 210         }
 211
 212         return WERR_ACCESS_DENIED;
 213 }
 214
 215 /**
 216  * Check whether the in-memory version of the subkyes of a
 217  * registry key needs update from disk.
 218  */
 219 bool reg_subkeys_need_update(REGISTRY_KEY *key, REGSUBKEY_CTR *subkeys)
 220 {
 221         if (key->ops && key->ops->subkeys_need_update)
 222         {
 223                 return key->ops->subkeys_need_update(subkeys);
 224         }
 225
 226         return false;
 227 }
 228
 229 /**
 230  * Check whether the in-memory version of the values of a
 231  * registry key needs update from disk.
 232  */
 233 bool reg_values_need_update(REGISTRY_KEY *key, REGVAL_CTR *values)
 234 {
 235         if (key->ops && key->ops->values_need_update)
 236         {
 237                 return key->ops->values_need_update(values);
 238         }
 239
 240         return false;
 241 }
 242