source4/dsdb/samdb/ldb_modules/samba_dsdb.c

   1 /*
   2    Samba4 module loading module
   3
   4    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2009
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 /*
  21  *  Name: ldb
  22  *
  23  *  Component: Samba4 module loading module
  24  *
  25  *  Description: Implement a single 'module' in the ldb database,
  26  *  which loads the remaining modules based on 'choice of configuration' attributes
  27  *
  28  *  This is to avoid forcing a reprovision of the ldb databases when we change the internal structure of the code
  29  *
  30  *  Author: Andrew Bartlett
  31  */
  32
  33 #include "includes.h"
  34 #include "lib/ldb/include/ldb.h"
  35 #include "lib/ldb/include/ldb_errors.h"
  36 #include "lib/ldb/include/ldb_module.h"
  37 #include "lib/ldb/include/ldb_private.h"
  38
  39 #include "dsdb/samdb/ldb_modules/util.h"
  40 #include "dsdb/samdb/samdb.h"
  41
  42 static int read_at_rootdse_record(struct ldb_context *ldb, struct ldb_module *module, TALLOC_CTX *mem_ctx,
  43                                   struct ldb_message **msg)
  44 {
  45         int ret;
  46         static const char *rootdse_attrs[] = { "defaultNamingContext", "configurationNamingContext", "schemaNamingContext", NULL };
  47         struct ldb_result *rootdse_res;
  48         struct ldb_dn *rootdse_dn;
  49         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
  50         if (!tmp_ctx) {
  51                 ldb_oom(ldb);
  52                 return LDB_ERR_OPERATIONS_ERROR;
  53         }
  54
  55         rootdse_dn = ldb_dn_new(tmp_ctx, ldb, "@ROOTDSE");
  56         if (!rootdse_dn) {
  57                 talloc_free(tmp_ctx);
  58                 ldb_oom(ldb);
  59                 return LDB_ERR_OPERATIONS_ERROR;
  60         }
  61
  62         ret = dsdb_module_search_dn(module, tmp_ctx, &rootdse_res, rootdse_dn, rootdse_attrs, 0);
  63         if (ret != LDB_SUCCESS) {
  64                 talloc_free(tmp_ctx);
  65                 return ret;
  66         }
  67
  68         talloc_steal(mem_ctx, rootdse_res->msgs);
  69         *msg = rootdse_res->msgs[0];
  70
  71         talloc_free(tmp_ctx);
  72
  73         return ret;
  74 }
  75
  76 static int prepare_modules_line(struct ldb_context *ldb,
  77                                 TALLOC_CTX *mem_ctx,
  78                                 const struct ldb_message *rootdse_msg,
  79                                 struct ldb_message *msg, const char *backend_attr,
  80                                 const char *backend_mod, const char **backend_mod_list)
  81 {
  82         int ret;
  83         const char **backend_full_list;
  84         const char *backend_dn;
  85         char *mod_list_string;
  86         char *full_string;
  87         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
  88         if (!tmp_ctx) {
  89                 ldb_oom(ldb);
  90                 return LDB_ERR_OPERATIONS_ERROR;
  91         }
  92
  93         if (backend_attr) {
  94                 backend_dn = ldb_msg_find_attr_as_string(rootdse_msg, backend_attr, NULL);
  95                 if (!backend_dn) {
  96                         ldb_asprintf_errstring(ldb,
  97                                                "samba_dsdb_init: "
  98                                                "unable to read %s from %s:%s",
  99                                                backend_attr, ldb_dn_get_linearized(rootdse_msg->dn),
 100                                                ldb_errstring(ldb));
 101                         return LDB_ERR_CONSTRAINT_VIOLATION;
 102                 }
 103         } else {
 104                 backend_dn = "*";
 105         }
 106
 107         if (backend_mod) {
 108                 backend_full_list = (const char **)str_list_make_single(tmp_ctx, backend_mod);
 109         } else {
 110                 backend_full_list = (const char **)str_list_make_empty(tmp_ctx);
 111         }
 112         if (!backend_full_list) {
 113                 talloc_free(tmp_ctx);
 114                 ldb_oom(ldb);
 115                 return LDB_ERR_OPERATIONS_ERROR;
 116         }
 117
 118         backend_full_list = str_list_append_const(backend_full_list, backend_mod_list);
 119         if (!backend_full_list) {
 120                 talloc_free(tmp_ctx);
 121                 ldb_oom(ldb);
 122                 return LDB_ERR_OPERATIONS_ERROR;
 123         }
 124
 125         mod_list_string = str_list_join(tmp_ctx, backend_full_list, ',');
 126         if (!mod_list_string) {
 127                 talloc_free(tmp_ctx);
 128                 ldb_oom(ldb);
 129                 return LDB_ERR_OPERATIONS_ERROR;
 130         }
 131
 132         full_string = talloc_asprintf(tmp_ctx, "%s:%s", backend_dn, mod_list_string);
 133         ret = ldb_msg_add_steal_string(msg, "modules", full_string);
 134         talloc_free(tmp_ctx);
 135         return ret;
 136 }
 137
 138 static int samba_dsdb_init(struct ldb_module *module)
 139 {
 140         struct ldb_context *ldb = ldb_module_get_ctx(module);
 141         int ret, len, i;
 142         TALLOC_CTX *tmp_ctx = talloc_new(module);
 143         struct ldb_result *res;
 144         struct ldb_message *rootdse_msg, *partition_msg;
 145         struct ldb_dn *samba_dsdb_dn;
 146         struct ldb_module *backend_module, *module_chain;
 147         const char **final_module_list, **reverse_module_list;
 148         /*
 149           Add modules to the list to activate them by default
 150           beware often order is important
 151
 152           Some Known ordering constraints:
 153           - rootdse must be first, as it makes redirects from "" -> cn=rootdse
 154           - extended_dn_in must be before objectclass.c, as it resolves the DN
 155           - objectclass must be before password_hash, because password_hash checks
 156             that the objectclass is of type person (filled in by objectclass
 157             module when expanding the objectclass list)
 158           - partition must be last
 159           - each partition has its own module list then
 160
 161           The list is presented here as a set of declarations to show the
 162           stack visually - the code below then handles the creation of the list
 163           based on the parameters loaded from the database.
 164         */
 165         static const char *modules_list[] = {"resolve_oids",
 166                                              "rootdse",
 167                                              "lazy_commit",
 168                                              "paged_results",
 169                                              "ranged_results",
 170                                              "anr",
 171                                              "server_sort",
 172                                              "asq",
 173                                              "extended_dn_store",
 174                                              "extended_dn_in",
 175                                              "rdn_name",
 176                                              "objectclass",
 177                                              "descriptor",
 178                                              "acl",
 179                                              "samldb",
 180                                              "password_hash",
 181                                              "operational",
 182                                              "kludge_acl",
 183                                              "schema_load",
 184                                              "instancetype",
 185                                              NULL };
 186
 187         const char *objectguid_module;
 188         /* if serverrole == "domain controller": */
 189         const char *repl_meta_data = "repl_meta_data";
 190         /*    else: */
 191         const char *objectguid = "objectguid";
 192
 193         const char **link_modules;
 194         static const char *tdb_modules_list[] = {
 195                 "subtree_rename",
 196                 "subtree_delete",
 197                 "linked_attributes",
 198                 NULL};
 199
 200         const char *extended_dn_module;
 201         const char *extended_dn_module_ldb = "extended_dn_out_ldb";
 202         const char *extended_dn_module_fds = "extended_dn_out_ldb";
 203         const char *extended_dn_module_openldap = "extended_dn_out_ldb";
 204
 205         static const char *modules_list2[] = {"show_deleted",
 206                                               "new_partition",
 207                                               "partition",
 208                                               NULL };
 209
 210         const char **backend_modules;
 211         static const char *fedora_ds_backend_modules[] = {
 212                 "nsuniqueid", "paged_searches", NULL };
 213         static const char *openldap_backend_modules[] = {
 214                 "nsuniqueid", "paged_searches", NULL };
 215
 216         static const char *samba_dsdb_attrs[] = { "backendType", "serverRole", NULL };
 217         const char *backendType, *serverRole;
 218
 219         if (!tmp_ctx) {
 220                 ldb_oom(ldb);
 221                 return LDB_ERR_OPERATIONS_ERROR;
 222         }
 223
 224         samba_dsdb_dn = ldb_dn_new(tmp_ctx, ldb, "@SAMBA_DSDB");
 225         if (!samba_dsdb_dn) {
 226                 talloc_free(tmp_ctx);
 227                 ldb_oom(ldb);
 228                 return LDB_ERR_OPERATIONS_ERROR;
 229         }
 230
 231 #define CHECK_LDB_RET(check_ret)                                \
 232         do {                                                    \
 233                 if (check_ret != LDB_SUCCESS) {                 \
 234                         talloc_free(tmp_ctx);                   \
 235                         return check_ret;                       \
 236                 }                                               \
 237         } while (0)
 238
 239         ret = dsdb_module_search_dn(module, tmp_ctx, &res, samba_dsdb_dn, samba_dsdb_attrs, 0);
 240         if (ret != LDB_SUCCESS) {
 241                 talloc_free(tmp_ctx);
 242                 return ret;
 243         }
 244
 245         backendType = ldb_msg_find_attr_as_string(res->msgs[0], "backendType", "ldb");
 246         serverRole = ldb_msg_find_attr_as_string(res->msgs[0], "serverRole", NULL);
 247
 248         backend_modules = NULL;
 249         if (strcasecmp(backendType, "ldb") == 0) {
 250                 if (strcasecmp(serverRole, "dc") == 0 || strcasecmp(serverRole, "domain controller") == 0) {
 251                         objectguid_module = repl_meta_data;
 252                 } else {
 253                         objectguid_module = objectguid;
 254                 }
 255                 extended_dn_module = extended_dn_module_ldb;
 256                 link_modules = tdb_modules_list;
 257         } else {
 258                 objectguid_module = NULL;
 259                 link_modules = NULL;
 260                 if (strcasecmp(backendType, "fedora-ds")) {
 261                         backend_modules = fedora_ds_backend_modules;
 262                         extended_dn_module = extended_dn_module_fds;
 263                 } else if (strcasecmp(backendType, "openldap")) {
 264                         backend_modules = openldap_backend_modules;
 265                         extended_dn_module = extended_dn_module_openldap;
 266                 }
 267         }
 268
 269 #define CHECK_MODULE_LIST \
 270         do {                                                    \
 271                 if (!final_module_list) {                       \
 272                         talloc_free(tmp_ctx);                   \
 273                         ldb_oom(ldb);                           \
 274                         return LDB_ERR_OPERATIONS_ERROR;        \
 275                 }                                               \
 276         } while (0)
 277
 278         final_module_list = str_list_copy_const(tmp_ctx, modules_list);
 279         CHECK_MODULE_LIST;
 280
 281         final_module_list = str_list_add_const(final_module_list, objectguid_module);
 282         CHECK_MODULE_LIST;
 283
 284         final_module_list = str_list_append_const(final_module_list, link_modules);
 285         CHECK_MODULE_LIST;
 286
 287         final_module_list = str_list_add_const(final_module_list, extended_dn_module);
 288         CHECK_MODULE_LIST;
 289
 290         final_module_list = str_list_append_const(final_module_list, modules_list2);
 291         CHECK_MODULE_LIST;
 292
 293
 294         ret = read_at_rootdse_record(ldb, module, tmp_ctx, &rootdse_msg);
 295         CHECK_LDB_RET(ret);
 296
 297         partition_msg = ldb_msg_new(tmp_ctx);
 298         partition_msg->dn = ldb_dn_new(partition_msg, ldb, "@" DSDB_OPAQUE_PARTITION_MODULE_MSG_OPAQUE_NAME);
 299
 300         ret = prepare_modules_line(ldb, tmp_ctx,
 301                                    rootdse_msg,
 302                                    partition_msg, "defaultNamingContext",
 303                                    "pdc_fsmo", backend_modules);
 304         CHECK_LDB_RET(ret);
 305
 306         ret = prepare_modules_line(ldb, tmp_ctx,
 307                                    rootdse_msg,
 308                                    partition_msg, "configurationNamingContext",
 309                                    "naming_fsmo", backend_modules);
 310         CHECK_LDB_RET(ret);
 311
 312         ret = prepare_modules_line(ldb, tmp_ctx,
 313                                    rootdse_msg,
 314                                    partition_msg, "schemaNamingContext",
 315                                    "schema_data", backend_modules);
 316         CHECK_LDB_RET(ret);
 317
 318         ret = prepare_modules_line(ldb, tmp_ctx,
 319                                    rootdse_msg,
 320                                    partition_msg, NULL,
 321                                    NULL, backend_modules);
 322         CHECK_LDB_RET(ret);
 323
 324         ret = ldb_set_opaque(ldb, DSDB_OPAQUE_PARTITION_MODULE_MSG_OPAQUE_NAME, partition_msg);
 325         CHECK_LDB_RET(ret);
 326
 327         talloc_steal(ldb, partition_msg);
 328
 329         /* Now prepare the module chain.  Oddly, we must give it to ldb_load_modules_list in REVERSE */
 330         for (len = 0; final_module_list[len]; len++) { /* noop */};
 331
 332         reverse_module_list = talloc_array(tmp_ctx, const char *, len+1);
 333         if (!reverse_module_list) {
 334                 talloc_free(tmp_ctx);
 335                 ldb_oom(ldb);
 336                 return LDB_ERR_OPERATIONS_ERROR;
 337         }
 338         for (i=0; i < len; i++) {
 339                 reverse_module_list[i] = final_module_list[(len - 1) - i];
 340         }
 341         reverse_module_list[i] = NULL;
 342
 343         /* The backend (at least until the partitions module
 344          * reconfigures things) is the next module in the currently
 345          * loaded chain */
 346         backend_module = module->next;
 347         ret = ldb_load_modules_list(ldb, reverse_module_list, backend_module, &module_chain);
 348         CHECK_LDB_RET(ret);
 349
 350         talloc_free(tmp_ctx);
 351         /* Set this as the 'next' module, so that we effectivly append it to module chain */
 352         module->next = module_chain;
 353
 354         return ldb_next_init(module);
 355 }
 356
 357 const struct ldb_module_ops ldb_samba_dsdb_module_ops = {
 358         .name              = "samba_dsdb",
 359         .init_context      = samba_dsdb_init,
 360 };