source/registry/reg_backend_smbconf.c

   1 /*
   2  *  Unix SMB/CIFS implementation.
   3  *  Virtual Windows Registry Layer
   4  *  Copyright (C) Volker Lendecke 2006
   5  *  Copyright (C) Michael Adam 2007
   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 #include "includes.h"
  22
  23 #undef DBGC_CLASS
  24 #define DBGC_CLASS DBGC_REGISTRY
  25
  26 extern REGISTRY_OPS regdb_ops;          /* these are the default */
  27
  28 static int smbconf_fetch_keys( const char *key, REGSUBKEY_CTR *subkey_ctr )
  29 {
  30         return regdb_ops.fetch_subkeys(key, subkey_ctr);
  31 }
  32
  33 static bool smbconf_store_keys( const char *key, REGSUBKEY_CTR *subkeys )
  34 {
  35         return regdb_ops.store_subkeys(key, subkeys);
  36 }
  37
  38 static int smbconf_fetch_values( const char *key, REGVAL_CTR *val )
  39 {
  40         return regdb_ops.fetch_values(key, val);
  41 }
  42
  43 static WERROR regval_hilvl_to_lolvl(TALLOC_CTX *mem_ctx, const char *valname,
  44                                     struct registry_value *src,
  45                                     REGISTRY_VALUE **dst)
  46 {
  47         WERROR err;
  48         DATA_BLOB value_data;
  49         REGISTRY_VALUE *newval = NULL;
  50
  51         if (dst == NULL) {
  52                 return WERR_INVALID_PARAM;
  53         }
  54
  55         err = registry_push_value(mem_ctx, src, &value_data);
  56         if (!W_ERROR_IS_OK(err)) {
  57                 DEBUG(10, ("error calling registry_push_value.\n"));
  58                 return err;
  59         }
  60
  61         newval = regval_compose(mem_ctx, valname, src->type,
  62                                 (char *)value_data.data, value_data.length);
  63         if (newval == NULL) {
  64                 DEBUG(10, ("error composing registry value. (no memory?)\n"));
  65                 return WERR_NOMEM;
  66         }
  67
  68         *dst = newval;
  69         return WERR_OK;
  70 }
  71
  72 static WERROR regval_lolvl_to_hilvl(TALLOC_CTX *mem_ctx, REGISTRY_VALUE *src,
  73                                     struct registry_value **dst)
  74 {
  75         if (dst == NULL) {
  76                 return WERR_INVALID_PARAM;
  77         }
  78
  79         return registry_pull_value(mem_ctx, dst, regval_type(src),
  80                                    regval_data_p(src), regval_size(src),
  81                                    regval_size(src));
  82 }
  83
  84 /*
  85  * Utility function used by smbconf_store_values to canonicalize
  86  * a registry value.
  87  * registry_pull_value / registry_push_value are used for (un)marshalling.
  88  */
  89 static REGISTRY_VALUE *smbconf_canonicalize_regval(TALLOC_CTX *mem_ctx,
  90                                                    REGISTRY_VALUE *theval)
  91 {
  92         char *valstr;
  93         size_t len;
  94         const char *canon_valname;
  95         const char *canon_valstr;
  96         bool inverse;
  97         struct registry_value *value;
  98         WERROR err;
  99         TALLOC_CTX *tmp_ctx;
 100         REGISTRY_VALUE *newval = NULL;
 101
 102         if (!lp_parameter_is_valid(regval_name(theval)) ||
 103             lp_parameter_is_canonical(regval_name(theval)))
 104         {
 105                 return theval;
 106         }
 107
 108         tmp_ctx = talloc_stackframe();
 109         if (tmp_ctx == NULL) {
 110                 DEBUG(1, ("out of memory...\n"));
 111                 goto done;
 112         }
 113
 114         err = regval_lolvl_to_hilvl(tmp_ctx, theval, &value);
 115         if (!W_ERROR_IS_OK(err)) {
 116                 goto done;
 117         }
 118
 119         /* we need the value-string zero-terminated */
 120         valstr = value->v.sz.str;
 121         len = value->v.sz.len;
 122         if (valstr[len - 1] != '\0') {
 123                 DEBUG(10, ("string is not '\\0'-terminated. adding '\\0'.\n"));
 124                 valstr = TALLOC_REALLOC_ARRAY(tmp_ctx, valstr, char, len + 1);
 125                 if (valstr == NULL) {
 126                         DEBUG(1, ("out of memory\n"));
 127                         goto done;
 128                 }
 129                 valstr[len] = '\0';
 130         }
 131
 132         if (!lp_canonicalize_parameter(regval_name(theval), &canon_valname,
 133                                        &inverse))
 134         {
 135                 DEBUG(5, ("Error: lp_canonicalize_parameter failed after "
 136                           "lp_parameter_is_valid. This should not happen!\n"));
 137                 goto done;
 138         }
 139         DEBUG(10, ("old value name: '%s', canonical value name: '%s'\n",
 140                    regval_name(theval), canon_valname));
 141         if (inverse && lp_string_is_valid_boolean(valstr)) {
 142                 lp_invert_boolean(valstr, &canon_valstr);
 143         } else {
 144                 canon_valstr = valstr;
 145         }
 146
 147         ZERO_STRUCTP(value);
 148         value->type = REG_SZ;
 149         value->v.sz.str = CONST_DISCARD(char *, canon_valstr);
 150         value->v.sz.len = strlen(canon_valstr) + 1;
 151
 152         err = regval_hilvl_to_lolvl(mem_ctx, canon_valname, value, &newval);
 153         if (!W_ERROR_IS_OK(err)) {
 154                 DEBUG(10, ("error calling regval_hilvl_to_lolvl.\n"));
 155                 goto done;
 156         }
 157
 158 done:
 159         TALLOC_FREE(tmp_ctx);
 160         return newval;
 161 }
 162
 163 static bool smbconf_store_values( const char *key, REGVAL_CTR *val )
 164 {
 165         int i;
 166         int num_values = regval_ctr_numvals(val);
 167         REGVAL_CTR *new_val_ctr;
 168
 169         /*
 170          * we build a second regval container and copy over the values,
 171          * possibly changing names to the canonical name, because when
 172          * canonicalizing parameter names and replacing the original parameter
 173          * (with reval_ctr_deletevalue and regval_ctr_addvalue) in the original
 174          * container, the order would change and that is not so good in the
 175          * "for" loop...  :-o
 176          */
 177         new_val_ctr = TALLOC_ZERO_P(val, REGVAL_CTR);
 178         if (new_val_ctr == NULL) {
 179                 DEBUG(1, ("out of memory\n"));
 180                 return False;
 181         }
 182
 183         for (i=0; i < num_values; i++) {
 184                 REGISTRY_VALUE *theval = regval_ctr_specific_value(val, i);
 185                 const char *valname = regval_name(theval);
 186                 int res;
 187
 188                 DEBUG(10, ("inspecting value '%s'\n", valname));
 189
 190                 /* unfortunately, we can not reject names that are not
 191                  * valid parameter names here, since e.g. regedit first
 192                  * creates values as "New Value #1" and so on and then
 193                  * drops into rename. */
 194
 195                 if (regval_type(theval) != REG_SZ) {
 196                         DEBUG(1, ("smbconf_store_values: only registry value "
 197                               "type REG_SZ currently allowed under key "
 198                               "smbconf\n"));
 199                         return False;
 200                 }
 201
 202                 if (registry_smbconf_valname_forbidden(valname)) {
 203                         DEBUG(1, ("smbconf_store_values: value '%s' forbidden "
 204                               "in registry.\n", valname));
 205                         return False;
 206                 }
 207
 208                 if (lp_parameter_is_valid(valname) &&
 209                     !lp_parameter_is_canonical(valname))
 210                 {
 211                         DEBUG(5, ("valid parameter '%s' given but it is a "
 212                                   "synonym. going to canonicalize it.\n",
 213                                   valname));
 214                         theval = smbconf_canonicalize_regval(val, theval);
 215                         if (theval == NULL) {
 216                                 DEBUG(10, ("error canonicalizing registry "
 217                                            "value\n"));
 218                                 return False;
 219                         }
 220                 } else {
 221                         DEBUG(10, ("%s parameter found, "
 222                                    "copying it to new container...\n",
 223                                    (lp_parameter_is_valid(valname)?
 224                                     "valid":"unknown")));
 225                 }
 226                 res = regval_ctr_copyvalue(new_val_ctr, theval);
 227                 if (res == 0) {
 228                         DEBUG(10, ("error calling regval_ctr_copyvalue. "
 229                                    "(no memory?)\n"));
 230                         return False;
 231                 }
 232                 DEBUG(10, ("parameter copied. container now has %d values.\n",
 233                            res));
 234         }
 235         return regdb_ops.store_values(key, new_val_ctr);
 236 }
 237
 238 static bool smbconf_reg_access_check(const char *keyname, uint32 requested,
 239                                      uint32 *granted,
 240                                      const struct nt_user_token *token)
 241 {
 242         if (!(user_has_privileges(token, &se_disk_operators))) {
 243                 return False;
 244         }
 245
 246         *granted = REG_KEY_ALL;
 247         return True;
 248 }
 249
 250 static WERROR smbconf_get_secdesc(TALLOC_CTX *mem_ctx, const char *key,
 251                                   struct security_descriptor **psecdesc)
 252 {
 253         return regdb_ops.get_secdesc(mem_ctx, key, psecdesc);
 254 }
 255
 256 static WERROR smbconf_set_secdesc(const char *key,
 257                                   struct security_descriptor *secdesc)
 258 {
 259         return regdb_ops.set_secdesc(key, secdesc);
 260 }
 261
 262
 263 /*
 264  * Table of function pointers for accessing smb.conf data
 265  */
 266
 267 REGISTRY_OPS smbconf_reg_ops = {
 268         .fetch_subkeys = smbconf_fetch_keys,
 269         .fetch_values = smbconf_fetch_values,
 270         .store_subkeys = smbconf_store_keys,
 271         .store_values = smbconf_store_values,
 272         .reg_access_check = smbconf_reg_access_check,
 273         .get_secdesc = smbconf_get_secdesc,
 274         .set_secdesc = smbconf_set_secdesc,
 275 };