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 SEC_DESC* construct_registry_sd( TALLOC_CTX *ctx )
  38 {
  39         SEC_ACE ace[3];
  40         SEC_ACCESS mask;
  41         size_t i = 0;
  42         SEC_DESC *sd;
  43         SEC_ACL *acl;
  44         size_t sd_size;
  45
  46         /* basic access for Everyone */
  47
  48         init_sec_access(&mask, REG_KEY_READ );
  49         init_sec_ace(&ace[i++], &global_sid_World, SEC_ACE_TYPE_ACCESS_ALLOWED, mask, 0);
  50
  51         /* Full Access 'BUILTIN\Administrators' */
  52
  53         init_sec_access(&mask, REG_KEY_ALL );
  54         init_sec_ace(&ace[i++], &global_sid_Builtin_Administrators, SEC_ACE_TYPE_ACCESS_ALLOWED, mask, 0);
  55
  56         /* Full Access 'NT Authority\System' */
  57
  58         init_sec_access(&mask, REG_KEY_ALL );
  59         init_sec_ace(&ace[i++], &global_sid_System, SEC_ACE_TYPE_ACCESS_ALLOWED, mask, 0);
  60
  61         /* create the security descriptor */
  62
  63         if ( !(acl = make_sec_acl(ctx, NT4_ACL_REVISION, i, ace)) )
  64                 return NULL;
  65
  66         if ( !(sd = make_sec_desc(ctx, SEC_DESC_REVISION, SEC_DESC_SELF_RELATIVE, NULL, NULL, NULL, acl, &sd_size)) )
  67                 return NULL;
  68
  69         return sd;
  70 }
  71
  72 /***********************************************************************
  73  High level wrapper function for storing registry subkeys
  74  ***********************************************************************/
  75
  76 bool store_reg_keys( REGISTRY_KEY *key, REGSUBKEY_CTR *subkeys )
  77 {
  78         if ( key->hook && key->hook->ops && key->hook->ops->store_subkeys )
  79                 return key->hook->ops->store_subkeys( key->name, subkeys );
  80
  81         return false;
  82 }
  83
  84 /***********************************************************************
  85  High level wrapper function for storing registry values
  86  ***********************************************************************/
  87
  88 bool store_reg_values( REGISTRY_KEY *key, REGVAL_CTR *val )
  89 {
  90         if ( key->hook && key->hook->ops && key->hook->ops->store_values )
  91                 return key->hook->ops->store_values( key->name, val );
  92
  93         return false;
  94 }
  95
  96 /***********************************************************************
  97  High level wrapper function for enumerating registry subkeys
  98  Initialize the TALLOC_CTX if necessary
  99  ***********************************************************************/
 100
 101 int fetch_reg_keys( REGISTRY_KEY *key, REGSUBKEY_CTR *subkey_ctr )
 102 {
 103         int result = -1;
 104
 105         if ( key->hook && key->hook->ops && key->hook->ops->fetch_subkeys )
 106                 result = key->hook->ops->fetch_subkeys( key->name, subkey_ctr );
 107
 108         return result;
 109 }
 110
 111 /***********************************************************************
 112  High level wrapper function for enumerating registry values
 113  ***********************************************************************/
 114
 115 int fetch_reg_values( REGISTRY_KEY *key, REGVAL_CTR *val )
 116 {
 117         int result = -1;
 118
 119         DEBUG(10, ("fetch_reg_values called for key '%s' (ops %p)\n", key->name,
 120                    (key->hook && key->hook->ops) ? (void *)key->hook->ops : NULL));
 121
 122         if ( key->hook && key->hook->ops && key->hook->ops->fetch_values )
 123                 result = key->hook->ops->fetch_values( key->name, val );
 124
 125         return result;
 126 }
 127
 128 /***********************************************************************
 129  High level access check for passing the required access mask to the
 130  underlying registry backend
 131  ***********************************************************************/
 132
 133 bool regkey_access_check( REGISTRY_KEY *key, uint32 requested, uint32 *granted,
 134                           const struct nt_user_token *token )
 135 {
 136         SEC_DESC *sec_desc;
 137         NTSTATUS status;
 138         WERROR err;
 139         TALLOC_CTX *mem_ctx;
 140
 141         /* use the default security check if the backend has not defined its
 142          * own */
 143
 144         if (key->hook && key->hook->ops && key->hook->ops->reg_access_check) {
 145                 return key->hook->ops->reg_access_check( key->name, requested,
 146                                                          granted, token );
 147         }
 148
 149         /*
 150          * The secdesc routines can't yet cope with a NULL talloc ctx sanely.
 151          */
 152
 153         if (!(mem_ctx = talloc_init("regkey_access_check"))) {
 154                 return false;
 155         }
 156
 157         err = regkey_get_secdesc(mem_ctx, key, &sec_desc);
 158
 159         if (!W_ERROR_IS_OK(err)) {
 160                 TALLOC_FREE(mem_ctx);
 161                 return false;
 162         }
 163
 164         se_map_generic( &requested, &reg_generic_map );
 165
 166         if (!se_access_check(sec_desc, token, requested, granted, &status)) {
 167                 TALLOC_FREE(mem_ctx);
 168                 return false;
 169         }
 170
 171         TALLOC_FREE(mem_ctx);
 172         return NT_STATUS_IS_OK(status);
 173 }
 174
 175 WERROR regkey_get_secdesc(TALLOC_CTX *mem_ctx, REGISTRY_KEY *key,
 176                           struct security_descriptor **psecdesc)
 177 {
 178         struct security_descriptor *secdesc;
 179
 180         if (key->hook && key->hook->ops && key->hook->ops->get_secdesc) {
 181                 WERROR err;
 182
 183                 err = key->hook->ops->get_secdesc(mem_ctx, key->name,
 184                                                   psecdesc);
 185                 if (W_ERROR_IS_OK(err)) {
 186                         return WERR_OK;
 187                 }
 188         }
 189
 190         if (!(secdesc = construct_registry_sd(mem_ctx))) {
 191                 return WERR_NOMEM;
 192         }
 193
 194         *psecdesc = secdesc;
 195         return WERR_OK;
 196 }
 197
 198 WERROR regkey_set_secdesc(REGISTRY_KEY *key,
 199                           struct security_descriptor *psecdesc)
 200 {
 201         if (key->hook && key->hook->ops && key->hook->ops->set_secdesc) {
 202                 return key->hook->ops->set_secdesc(key->name, psecdesc);
 203         }
 204
 205         return WERR_ACCESS_DENIED;
 206 }
 207
 208 /**
 209  * Check whether the in-memory version of the subkyes of a
 210  * registry key needs update from disk.
 211  */
 212 bool reg_subkeys_need_update(REGISTRY_KEY *key, REGSUBKEY_CTR *subkeys)
 213 {
 214         if (key->hook && key->hook->ops && key->hook->ops->subkeys_need_update)
 215         {
 216                 return key->hook->ops->subkeys_need_update(subkeys);
 217         }
 218
 219         return false;
 220 }
 221
 222 /**
 223  * Check whether the in-memory version of the values of a
 224  * registry key needs update from disk.
 225  */
 226 bool reg_values_need_update(REGISTRY_KEY *key, REGVAL_CTR *values)
 227 {
 228         if (key->hook && key->hook->ops && key->hook->ops->values_need_update)
 229         {
 230                 return key->hook->ops->values_need_update(values);
 231         }
 232
 233         return false;
 234 }
 235