source4/dsdb/samdb/ldb_modules/schema_util.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    dsdb module schema utility functions
   5
   6    Copyright (C) Kamen Mazdrashki <kamenim@samba.org> 2010
   7    Copyright (C) Andrew Tridgell 2010
   8    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2010
   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 "dsdb/common/util.h"
  26 #include "dsdb/samdb/samdb.h"
  27 #include "dsdb/samdb/ldb_modules/util.h"
  28 #include <ldb_module.h>
  29 #include "librpc/gen_ndr/ndr_drsuapi.h"
  30 #include "librpc/gen_ndr/ndr_drsblobs.h"
  31 #include "param/param.h"
  32
  33 /**
  34  * Reads schema_info structure from schemaInfo
  35  * attribute on SCHEMA partition
  36  *
  37  * @param dsdb_flags    DSDB_FLAG_... flag of 0
  38  */
  39 int dsdb_module_schema_info_blob_read(struct ldb_module *ldb_module,
  40                                       uint32_t dsdb_flags,
  41                                       TALLOC_CTX *mem_ctx,
  42                                       struct ldb_val *schema_info_blob,
  43                                       struct ldb_request *parent)
  44 {
  45         int ldb_err;
  46         const struct ldb_val *blob_val;
  47         struct ldb_dn *schema_dn;
  48         struct ldb_result *schema_res = NULL;
  49         static const char *schema_attrs[] = {
  50                 "schemaInfo",
  51                 NULL
  52         };
  53
  54         schema_dn = ldb_get_schema_basedn(ldb_module_get_ctx(ldb_module));
  55         if (!schema_dn) {
  56                 DEBUG(0,("dsdb_module_schema_info_blob_read: no schema dn present!\n"));
  57                 return ldb_operr(ldb_module_get_ctx(ldb_module));
  58         }
  59
  60         ldb_err = dsdb_module_search(ldb_module, mem_ctx, &schema_res, schema_dn,
  61                                      LDB_SCOPE_BASE, schema_attrs, dsdb_flags, parent,
  62                                      NULL);
  63         if (ldb_err == LDB_ERR_NO_SUCH_OBJECT) {
  64                 DEBUG(0,("dsdb_module_schema_info_blob_read: Schema DN not found!\n"));
  65                 talloc_free(schema_res);
  66                 return ldb_err;
  67         } else if (ldb_err != LDB_SUCCESS) {
  68                 DEBUG(0,("dsdb_module_schema_info_blob_read: failed to find schemaInfo attribute\n"));
  69                 talloc_free(schema_res);
  70                 return ldb_err;
  71         }
  72
  73         blob_val = ldb_msg_find_ldb_val(schema_res->msgs[0], "schemaInfo");
  74         if (!blob_val) {
  75                 ldb_asprintf_errstring(ldb_module_get_ctx(ldb_module),
  76                                        "dsdb_module_schema_info_blob_read: no schemaInfo attribute found");
  77                 talloc_free(schema_res);
  78                 return LDB_ERR_NO_SUCH_ATTRIBUTE;
  79         }
  80
  81         /* transfer .data ownership to mem_ctx */
  82         schema_info_blob->length = blob_val->length;
  83         schema_info_blob->data = talloc_steal(mem_ctx, blob_val->data);
  84
  85         talloc_free(schema_res);
  86
  87         return LDB_SUCCESS;
  88 }
  89
  90 /**
  91  * Prepares ldb_msg to be used for updating schemaInfo value in DB
  92  */
  93 static int dsdb_schema_info_write_prepare(struct ldb_context *ldb,
  94                                           struct ldb_val *schema_info_blob,
  95                                           TALLOC_CTX *mem_ctx,
  96                                           struct ldb_message **_msg)
  97 {
  98         int ldb_err;
  99         struct ldb_message *msg;
 100         struct ldb_dn *schema_dn;
 101         struct ldb_message_element *return_el;
 102
 103         schema_dn = ldb_get_schema_basedn(ldb);
 104         if (!schema_dn) {
 105                 DEBUG(0,("dsdb_schema_info_write_prepare: no schema dn present\n"));
 106                 return ldb_operr(ldb);
 107         }
 108
 109         /* prepare ldb_msg to update schemaInfo */
 110         msg = ldb_msg_new(mem_ctx);
 111         if (msg == NULL) {
 112                 return ldb_oom(ldb);
 113         }
 114
 115         msg->dn = schema_dn;
 116         ldb_err = ldb_msg_add_value(msg, "schemaInfo", schema_info_blob, &return_el);
 117         if (ldb_err != 0) {
 118                 ldb_asprintf_errstring(ldb, "dsdb_schema_info_write_prepare: ldb_msg_add_value failed - %s\n",
 119                                        ldb_strerror(ldb_err));
 120                 talloc_free(msg);
 121                 return ldb_err;
 122         }
 123
 124         /* mark schemaInfo element for replacement */
 125         return_el->flags = LDB_FLAG_MOD_REPLACE;
 126
 127         *_msg = msg;
 128
 129         return LDB_SUCCESS;
 130 }
 131
 132
 133
 134 /**
 135  * Writes schema_info structure into schemaInfo
 136  * attribute on SCHEMA partition
 137  *
 138  * @param dsdb_flags    DSDB_FLAG_... flag of 0
 139  */
 140 int dsdb_module_schema_info_blob_write(struct ldb_module *ldb_module,
 141                                        uint32_t dsdb_flags,
 142                                        struct ldb_val *schema_info_blob,
 143                                        struct ldb_request *parent)
 144 {
 145         int ldb_err;
 146         struct ldb_message *msg;
 147         TALLOC_CTX *temp_ctx;
 148
 149         temp_ctx = talloc_new(ldb_module);
 150         if (temp_ctx == NULL) {
 151                 return ldb_module_oom(ldb_module);
 152         }
 153
 154         /* write serialized schemaInfo into LDB */
 155         ldb_err = dsdb_schema_info_write_prepare(ldb_module_get_ctx(ldb_module),
 156                                                  schema_info_blob,
 157                                                  temp_ctx, &msg);
 158         if (ldb_err != LDB_SUCCESS) {
 159                 talloc_free(temp_ctx);
 160                 return ldb_err;
 161         }
 162
 163
 164         ldb_err = dsdb_module_modify(ldb_module, msg, dsdb_flags, parent);
 165
 166         talloc_free(temp_ctx);
 167
 168         if (ldb_err != LDB_SUCCESS) {
 169                 ldb_asprintf_errstring(ldb_module_get_ctx(ldb_module),
 170                                        "dsdb_module_schema_info_blob_write: dsdb_replace failed: %s (%s)\n",
 171                                        ldb_strerror(ldb_err),
 172                                        ldb_errstring(ldb_module_get_ctx(ldb_module)));
 173                 return ldb_err;
 174         }
 175
 176         return LDB_SUCCESS;
 177 }
 178
 179
 180 /**
 181  * Reads schema_info structure from schemaInfo
 182  * attribute on SCHEMA partition
 183  */
 184 static int dsdb_module_schema_info_read(struct ldb_module *ldb_module,
 185                                         uint32_t dsdb_flags,
 186                                         TALLOC_CTX *mem_ctx,
 187                                         struct dsdb_schema_info **_schema_info,
 188                                         struct ldb_request *parent)
 189 {
 190         int ret;
 191         DATA_BLOB ndr_blob;
 192         TALLOC_CTX *temp_ctx;
 193         WERROR werr;
 194
 195         temp_ctx = talloc_new(mem_ctx);
 196         if (temp_ctx == NULL) {
 197                 return ldb_module_oom(ldb_module);
 198         }
 199
 200         /* read serialized schemaInfo from LDB  */
 201         ret = dsdb_module_schema_info_blob_read(ldb_module, dsdb_flags, temp_ctx, &ndr_blob, parent);
 202         if (ret != LDB_SUCCESS) {
 203                 talloc_free(temp_ctx);
 204                 return ret;
 205         }
 206
 207         /* convert NDR blob to dsdb_schema_info object */
 208         werr = dsdb_schema_info_from_blob(&ndr_blob,
 209                                           mem_ctx,
 210                                           _schema_info);
 211         talloc_free(temp_ctx);
 212
 213         if (W_ERROR_EQUAL(werr, WERR_DS_NO_ATTRIBUTE_OR_VALUE)) {
 214                 return LDB_ERR_NO_SUCH_ATTRIBUTE;
 215         }
 216
 217         if (!W_ERROR_IS_OK(werr)) {
 218                 ldb_asprintf_errstring(ldb_module_get_ctx(ldb_module), __location__ ": failed to get schema_info");
 219                 return ldb_operr(ldb_module_get_ctx(ldb_module));
 220         }
 221
 222         return LDB_SUCCESS;
 223 }
 224
 225 /**
 226  * Writes schema_info structure into schemaInfo
 227  * attribute on SCHEMA partition
 228  *
 229  * @param dsdb_flags    DSDB_FLAG_... flag of 0
 230  */
 231 static int dsdb_module_schema_info_write(struct ldb_module *ldb_module,
 232                                          uint32_t dsdb_flags,
 233                                          const struct dsdb_schema_info *schema_info,
 234                                          struct ldb_request *parent)
 235 {
 236         WERROR werr;
 237         int ret;
 238         DATA_BLOB ndr_blob;
 239         TALLOC_CTX *temp_ctx;
 240
 241         temp_ctx = talloc_new(ldb_module);
 242         if (temp_ctx == NULL) {
 243                 return ldb_module_oom(temp_ctx);
 244         }
 245
 246         /* convert schema_info to a blob */
 247         werr = dsdb_blob_from_schema_info(schema_info, temp_ctx, &ndr_blob);
 248         if (!W_ERROR_IS_OK(werr)) {
 249                 talloc_free(temp_ctx);
 250                 ldb_asprintf_errstring(ldb_module_get_ctx(ldb_module), __location__ ": failed to get schema_info");
 251                 return ldb_operr(ldb_module_get_ctx(ldb_module));
 252         }
 253
 254         /* write serialized schemaInfo into LDB */
 255         ret = dsdb_module_schema_info_blob_write(ldb_module, dsdb_flags, &ndr_blob, parent);
 256
 257         talloc_free(temp_ctx);
 258
 259         return ret;
 260 }
 261
 262
 263 /**
 264  * Increments schemaInfo revision and save it to DB
 265  * setting our invocationID in the process
 266  * NOTE: this function should be called in a transaction
 267  * much in the same way prefixMap update function is called
 268  *
 269  * @param ldb_module    current module
 270  * @param schema        schema cache
 271  * @param dsdb_flags    DSDB_FLAG_... flag of 0
 272  */
 273 int dsdb_module_schema_info_update(struct ldb_module *ldb_module,
 274                                    struct dsdb_schema *schema,
 275                                    int dsdb_flags, struct ldb_request *parent)
 276 {
 277         int ret;
 278         const struct GUID *invocation_id;
 279         DATA_BLOB ndr_blob;
 280         struct dsdb_schema_info *schema_info;
 281         const char *schema_info_str;
 282         WERROR werr;
 283         TALLOC_CTX *temp_ctx = talloc_new(schema);
 284         if (temp_ctx == NULL) {
 285                 return ldb_module_oom(ldb_module);
 286         }
 287
 288         invocation_id = samdb_ntds_invocation_id(ldb_module_get_ctx(ldb_module));
 289         if (!invocation_id) {
 290                 talloc_free(temp_ctx);
 291                 return ldb_operr(ldb_module_get_ctx(ldb_module));
 292         }
 293
 294         /* read serialized schemaInfo from LDB  */
 295         ret = dsdb_module_schema_info_read(ldb_module, dsdb_flags, temp_ctx, &schema_info, parent);
 296         if (ret == LDB_ERR_NO_SUCH_ATTRIBUTE) {
 297                 /* make default value in case
 298                  * we have no schemaInfo value yet */
 299                 werr = dsdb_schema_info_new(temp_ctx, &schema_info);
 300                 if (!W_ERROR_IS_OK(werr)) {
 301                         talloc_free(temp_ctx);
 302                         return ldb_module_oom(ldb_module);
 303                 }
 304                 ret = LDB_SUCCESS;
 305         }
 306         if (ret != LDB_SUCCESS) {
 307                 talloc_free(temp_ctx);
 308                 return ret;
 309         }
 310
 311         /* update schemaInfo */
 312         schema_info->revision++;
 313         schema_info->invocation_id = *invocation_id;
 314
 315         ret = dsdb_module_schema_info_write(ldb_module, dsdb_flags, schema_info, parent);
 316         if (ret != LDB_SUCCESS) {
 317                 ldb_asprintf_errstring(ldb_module_get_ctx(ldb_module),
 318                                        "dsdb_module_schema_info_update: failed to save schemaInfo - %s\n",
 319                                        ldb_strerror(ret));
 320                 talloc_free(temp_ctx);
 321                 return ret;
 322         }
 323
 324         /* finally, update schema_info in the cache */
 325         werr = dsdb_blob_from_schema_info(schema_info, temp_ctx, &ndr_blob);
 326         if (!W_ERROR_IS_OK(werr)) {
 327                 ldb_asprintf_errstring(ldb_module_get_ctx(ldb_module), "Failed to get schema info");
 328                 talloc_free(temp_ctx);
 329                 return ldb_operr(ldb_module_get_ctx(ldb_module));
 330         }
 331
 332         schema_info_str = hex_encode_talloc(schema, ndr_blob.data, ndr_blob.length);
 333         if (!schema_info_str) {
 334                 talloc_free(temp_ctx);
 335                 return ldb_module_oom(ldb_module);
 336         }
 337
 338         talloc_unlink(schema, discard_const(schema->schema_info));
 339         schema->schema_info = schema_info_str;
 340
 341         talloc_free(temp_ctx);
 342         return LDB_SUCCESS;
 343 }