lib/ldb/include/ldb_module.h

   1 /*
   2    ldb database library
   3
   4    Copyright (C) Simo Sorce         2008
   5
   6      ** NOTE! The following LGPL license applies to the ldb
   7      ** library. This does NOT imply that all of Samba is released
   8      ** under the LGPL
   9
  10    This library is free software; you can redistribute it and/or
  11    modify it under the terms of the GNU Lesser General Public
  12    License as published by the Free Software Foundation; either
  13    version 3 of the License, or (at your option) any later version.
  14
  15    This library 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 GNU
  18    Lesser General Public License for more details.
  19
  20    You should have received a copy of the GNU Lesser General Public
  21    License along with this library; if not, see <http://www.gnu.org/licenses/>.
  22 */
  23
  24 /*
  25  *  Name: ldb
  26  *
  27  *  Component: ldb module header
  28  *
  29  *  Description: defines ldb modules structures and helpers
  30  *
  31  */
  32
  33 #ifndef _LDB_MODULE_H_
  34 #define _LDB_MODULE_H_
  35
  36 #include <ldb.h>
  37
  38 struct ldb_context;
  39 struct ldb_module;
  40
  41 /**
  42    internal flag bits on message elements. Must be within LDB_FLAG_INTERNAL_MASK
  43  */
  44 #define LDB_FLAG_INTERNAL_DISABLE_VALIDATION 0x10
  45
  46 /* disable any single value checking on this attribute */
  47 #define LDB_FLAG_INTERNAL_DISABLE_SINGLE_VALUE_CHECK 0x20
  48
  49 /* attribute has failed access check and must not be exposed */
  50 #define LDB_FLAG_INTERNAL_INACCESSIBLE_ATTRIBUTE 0x40
  51
  52 /* force single value checking on this attribute */
  53 #define LDB_FLAG_INTERNAL_FORCE_SINGLE_VALUE_CHECK 0x80
  54
  55 /* an extended match rule that always fails to match */
  56 #define SAMBA_LDAP_MATCH_ALWAYS_FALSE "1.3.6.1.4.1.7165.4.5.1"
  57
  58 /* The const char * const * pointer to a list of secret (password)
  59  * attributes, not to be printed in trace messages */
  60 #define LDB_SECRET_ATTRIBUTE_LIST_OPAQUE "LDB_SECRET_ATTRIBUTE_LIST"
  61
  62 /*
  63    these function pointers define the operations that a ldb module can intercept
  64 */
  65 struct ldb_module_ops {
  66         const char *name;
  67         int (*init_context) (struct ldb_module *);
  68         int (*search)(struct ldb_module *, struct ldb_request *); /* search */
  69         int (*add)(struct ldb_module *, struct ldb_request *); /* add */
  70         int (*modify)(struct ldb_module *, struct ldb_request *); /* modify */
  71         int (*del)(struct ldb_module *, struct ldb_request *); /* delete */
  72         int (*rename)(struct ldb_module *, struct ldb_request *); /* rename */
  73         int (*request)(struct ldb_module *, struct ldb_request *); /* match any other operation */
  74         int (*extended)(struct ldb_module *, struct ldb_request *); /* extended operations */
  75         int (*start_transaction)(struct ldb_module *);
  76         int (*prepare_commit)(struct ldb_module *);
  77         int (*end_transaction)(struct ldb_module *);
  78         int (*del_transaction)(struct ldb_module *);
  79         int (*sequence_number)(struct ldb_module *, struct ldb_request *);
  80         int (*read_lock)(struct ldb_module *);
  81         int (*read_unlock)(struct ldb_module *);
  82         void *private_data;
  83 };
  84
  85
  86 /* The following definitions come from lib/ldb/common/ldb_debug.c  */
  87 void ldb_debug(struct ldb_context *ldb, enum ldb_debug_level level, const char *fmt, ...) PRINTF_ATTRIBUTE(3, 4);
  88 void ldb_debug_set(struct ldb_context *ldb, enum ldb_debug_level level,
  89                    const char *fmt, ...) PRINTF_ATTRIBUTE(3, 4);
  90 void ldb_debug_add(struct ldb_context *ldb, const char *fmt, ...) PRINTF_ATTRIBUTE(2, 3);
  91 void ldb_debug_end(struct ldb_context *ldb, enum ldb_debug_level level);
  92 void ldb_vdebug(struct ldb_context *ldb, enum ldb_debug_level level, const char *fmt, va_list ap) PRINTF_ATTRIBUTE(3, 0);
  93
  94 #define ldb_error(ldb, ecode, reason) ldb_error_at(ldb, ecode, reason, __FILE__, __LINE__)
  95 #define ldb_module_error(module, ecode, reason) ldb_error_at(ldb_module_get_ctx(module), ecode, reason, __FILE__, __LINE__)
  96
  97 #define ldb_oom(ldb) ldb_error(ldb, LDB_ERR_OPERATIONS_ERROR, "ldb out of memory")
  98 #define ldb_module_oom(module) ldb_oom(ldb_module_get_ctx(module))
  99 #define ldb_operr(ldb) ldb_error(ldb, LDB_ERR_OPERATIONS_ERROR, "operations error")
 100 #define ldb_module_operr(module) ldb_error(ldb_module_get_ctx(module), LDB_ERR_OPERATIONS_ERROR, "operations error")
 101
 102 /* The following definitions come from lib/ldb/common/ldb.c  */
 103
 104 void ldb_request_set_state(struct ldb_request *req, int state);
 105 int ldb_request_get_status(struct ldb_request *req);
 106
 107 unsigned int ldb_get_create_perms(struct ldb_context *ldb);
 108
 109 const struct ldb_schema_syntax *ldb_standard_syntax_by_name(struct ldb_context *ldb,
 110                                                             const char *syntax);
 111
 112 /* The following definitions come from lib/ldb/common/ldb_attributes.c  */
 113
 114 int ldb_schema_attribute_add_with_syntax(struct ldb_context *ldb,
 115                                          const char *name,
 116                                          unsigned flags,
 117                                          const struct ldb_schema_syntax *syntax);
 118 int ldb_schema_attribute_add(struct ldb_context *ldb,
 119                              const char *name,
 120                              unsigned flags,
 121                              const char *syntax);
 122 void ldb_schema_attribute_remove(struct ldb_context *ldb, const char *name);
 123
 124 /* we allow external code to override the name -> schema_attribute function */
 125 typedef const struct ldb_schema_attribute *(*ldb_attribute_handler_override_fn_t)(struct ldb_context *, void *, const char *);
 126
 127 /**
 128   Allow the caller to define a callback for the attribute handler
 129
 130   \param ldb The ldb context
 131   \param override The callback to be used for attribute lookups
 132   \param private_data Private data for the callback
 133
 134 */
 135 void ldb_schema_attribute_set_override_handler(struct ldb_context *ldb,
 136                                                ldb_attribute_handler_override_fn_t override,
 137                                                void *private_data);
 138
 139 /**
 140   Allow the caller to define that the callback for the attribute handler
 141   also overrides the index list
 142
 143   \param ldb The ldb context
 144   \param one_level_indexes Indicates that the index for SCOPE_ONELEVEL
 145          should also be maintained
 146
 147 */
 148 void ldb_schema_set_override_indexlist(struct ldb_context *ldb,
 149                                        bool one_level_indexes);
 150
 151 /* A useful function to build comparison functions with */
 152 int ldb_any_comparison(struct ldb_context *ldb, void *mem_ctx,
 153                        ldb_attr_handler_t canonicalise_fn,
 154                        const struct ldb_val *v1,
 155                        const struct ldb_val *v2);
 156
 157 /* The following definitions come from lib/ldb/common/ldb_controls.c  */
 158 int ldb_save_controls(struct ldb_control *exclude, struct ldb_request *req, struct ldb_control ***saver);
 159 /* Returns a list of controls, except the one specified.  Included
 160  * controls become a child of returned list if they were children of
 161  * controls_in */
 162 struct ldb_control **ldb_controls_except_specified(struct ldb_control **controls_in,
 163                                                TALLOC_CTX *mem_ctx,
 164                                                struct ldb_control *exclude);
 165 int ldb_check_critical_controls(struct ldb_control **controls);
 166
 167 /* The following definitions come from lib/ldb/common/ldb_ldif.c  */
 168 int ldb_should_b64_encode(struct ldb_context *ldb, const struct ldb_val *val);
 169
 170 /* The following definitions come from lib/ldb/common/ldb_match.c  */
 171 int ldb_match_msg(struct ldb_context *ldb,
 172                   const struct ldb_message *msg,
 173                   const struct ldb_parse_tree *tree,
 174                   struct ldb_dn *base,
 175                   enum ldb_scope scope);
 176
 177 int ldb_match_msg_error(struct ldb_context *ldb,
 178                         const struct ldb_message *msg,
 179                         const struct ldb_parse_tree *tree,
 180                         struct ldb_dn *base,
 181                         enum ldb_scope scope,
 182                         bool *matched);
 183
 184 int ldb_match_msg_objectclass(const struct ldb_message *msg,
 185                               const char *objectclass);
 186
 187 int ldb_register_extended_match_rules(struct ldb_context *ldb);
 188
 189 /* The following definitions come from lib/ldb/common/ldb_modules.c  */
 190
 191 struct ldb_module *ldb_module_new(TALLOC_CTX *memctx,
 192                                   struct ldb_context *ldb,
 193                                   const char *module_name,
 194                                   const struct ldb_module_ops *ops);
 195
 196 const char * ldb_module_get_name(struct ldb_module *module);
 197 struct ldb_context *ldb_module_get_ctx(struct ldb_module *module);
 198 void *ldb_module_get_private(struct ldb_module *module);
 199 void ldb_module_set_private(struct ldb_module *module, void *private_data);
 200 const struct ldb_module_ops *ldb_module_get_ops(struct ldb_module *module);
 201
 202 int ldb_next_request(struct ldb_module *module, struct ldb_request *request);
 203 int ldb_next_start_trans(struct ldb_module *module);
 204 int ldb_next_end_trans(struct ldb_module *module);
 205 int ldb_next_del_trans(struct ldb_module *module);
 206 int ldb_next_prepare_commit(struct ldb_module *module);
 207 int ldb_next_init(struct ldb_module *module);
 208 int ldb_next_read_lock(struct ldb_module *module);
 209 int ldb_next_read_unlock(struct ldb_module *module);
 210
 211 void ldb_set_errstring(struct ldb_context *ldb, const char *err_string);
 212 void ldb_asprintf_errstring(struct ldb_context *ldb, const char *format, ...) PRINTF_ATTRIBUTE(2,3);
 213 void ldb_reset_err_string(struct ldb_context *ldb);
 214 int ldb_error_at(struct ldb_context *ldb, int ecode, const char *reason, const char *file, int line);
 215
 216 const char *ldb_default_modules_dir(void);
 217
 218 int ldb_register_module(const struct ldb_module_ops *);
 219
 220 typedef int (*ldb_connect_fn)(struct ldb_context *ldb, const char *url,
 221                               unsigned int flags, const char *options[],
 222                               struct ldb_module **module);
 223
 224 /**
 225  Require that LDB use a private event context for each request
 226
 227  A private event context may need to be created to avoid nested event
 228  loops during ldb_tdb with the locks held.  This indicates that a
 229  backend is in use that requires this to hold locks safely.
 230
 231  \param handle The ldb handle to set the flag on
 232  */
 233 void ldb_set_require_private_event_context(struct ldb_context *ldb);
 234
 235 struct ldb_backend_ops {
 236         const char *name;
 237         ldb_connect_fn connect_fn;
 238 };
 239
 240 const char *ldb_default_modules_dir(void);
 241
 242 int ldb_register_backend(const char *url_prefix, ldb_connect_fn, bool);
 243
 244 struct ldb_handle *ldb_handle_new(TALLOC_CTX *mem_ctx, struct ldb_context *ldb);
 245
 246 /**
 247  Obtains the private event context for the handle,
 248
 249  A private event context may have been created to avoid nested event
 250  loops during ldb_tdb with the locks held.  Otherwise return the
 251  global one.
 252
 253  \param handle The ldb handle to obtain the event context for
 254  \return the tevent event context for this handle (private or global)
 255  */
 256 struct tevent_context *ldb_handle_get_event_context(struct ldb_handle *handle);
 257
 258 int ldb_module_send_entry(struct ldb_request *req,
 259                           struct ldb_message *msg,
 260                           struct ldb_control **ctrls);
 261
 262 int ldb_module_send_referral(struct ldb_request *req,
 263                                            char *ref);
 264
 265 int ldb_module_done(struct ldb_request *req,
 266                     struct ldb_control **ctrls,
 267                     struct ldb_extended *response,
 268                     int error);
 269
 270 int ldb_mod_register_control(struct ldb_module *module, const char *oid);
 271
 272 void ldb_set_default_dns(struct ldb_context *ldb);
 273 /**
 274   Add a ldb_control to a ldb_reply
 275
 276   \param ares the reply struct where to add the control
 277   \param oid the object identifier of the control as string
 278   \param critical whether the control should be critical or not
 279   \param data a talloc pointer to the control specific data
 280
 281   \return result code (LDB_SUCCESS on success, or a failure code)
 282 */
 283 int ldb_reply_add_control(struct ldb_reply *ares, const char *oid, bool critical, void *data);
 284
 285 /**
 286   mark a request as untrusted.
 287
 288   This tells the rootdse module to remove unregistered controls
 289
 290   \param req the request to mark as untrusted
 291 */
 292 void ldb_req_mark_untrusted(struct ldb_request *req);
 293
 294 /**
 295   mark a request as trusted.
 296
 297   This tells the rootdse module to allow unregistered controls
 298
 299   \param req the request to mark as trusted
 300 */
 301 void ldb_req_mark_trusted(struct ldb_request *req);
 302
 303 /**
 304    return true is a request is untrusted
 305
 306    This indicates the request came across a trust boundary
 307    for example over LDAP
 308
 309   \param req the request check
 310   \return is req trusted
 311 */
 312 bool ldb_req_is_untrusted(struct ldb_request *req);
 313
 314 /**
 315   set custom flags. Those flags are set by applications using ldb,
 316   they are application dependent and the same bit can have different
 317   meaning in different application.
 318  */
 319 void ldb_req_set_custom_flags(struct ldb_request *req, uint32_t flags);
 320
 321 /**
 322   get custom flags. Those flags are set by applications using ldb,
 323   they are application dependent and the same bit can have different
 324   meaning in different application.
 325  */
 326 uint32_t ldb_req_get_custom_flags(struct ldb_request *req);
 327
 328 /* load all modules from the given directory */
 329 int ldb_modules_load(const char *modules_path, const char *version);
 330
 331 /* init functions prototype */
 332 typedef int (*ldb_module_init_fn)(const char *);
 333
 334 /*
 335   general ldb hook function
 336  */
 337 enum ldb_module_hook_type { LDB_MODULE_HOOK_CMDLINE_OPTIONS     = 1,
 338                             LDB_MODULE_HOOK_CMDLINE_PRECONNECT  = 2,
 339                             LDB_MODULE_HOOK_CMDLINE_POSTCONNECT = 3 };
 340
 341 typedef int (*ldb_hook_fn)(struct ldb_context *, enum ldb_module_hook_type );
 342
 343 /*
 344   register a ldb hook function
 345  */
 346 int ldb_register_hook(ldb_hook_fn hook_fn);
 347
 348 /*
 349   call ldb hooks of a given type
 350  */
 351 int ldb_modules_hook(struct ldb_context *ldb, enum ldb_module_hook_type t);
 352
 353 #define LDB_MODULE_CHECK_VERSION(version) do { \
 354  if (strcmp(version, LDB_VERSION) != 0) { \
 355         fprintf(stderr, "ldb: module version mismatch in %s : ldb_version=%s module_version=%s\n", \
 356                         __FILE__, version, LDB_VERSION); \
 357         return LDB_ERR_UNAVAILABLE; \
 358  }} while (0)
 359
 360
 361 /*
 362   return a string representation of the calling chain for the given
 363   ldb request
 364  */
 365 char *ldb_module_call_chain(struct ldb_request *req, TALLOC_CTX *mem_ctx);
 366
 367 /*
 368   return the next module in the chain
 369  */
 370 struct ldb_module *ldb_module_next(struct ldb_module *module);
 371
 372 /*
 373   set the next module in the module chain
 374  */
 375 void ldb_module_set_next(struct ldb_module *module, struct ldb_module *next);
 376
 377 /*
 378   load a list of modules
 379  */
 380 int ldb_module_load_list(struct ldb_context *ldb, const char **module_list,
 381                          struct ldb_module *backend, struct ldb_module **out);
 382
 383 /*
 384   get the popt_options pointer in the ldb structure. This allows a ldb
 385   module to change the command line parsing
 386  */
 387 struct poptOption **ldb_module_popt_options(struct ldb_context *ldb);
 388
 389 /* modules are called in inverse order on the stack.
 390    Lets place them as an admin would think the right order is.
 391    Modules order is important */
 392 const char **ldb_modules_list_from_string(struct ldb_context *ldb, TALLOC_CTX *mem_ctx, const char *string);
 393
 394 /*
 395   return the current ldb flags LDB_FLG_*
 396  */
 397 uint32_t ldb_module_flags(struct ldb_context *ldb);
 398
 399 int ldb_module_connect_backend(struct ldb_context *ldb,
 400                                const char *url,
 401                                const char *options[],
 402                                struct ldb_module **backend_module);
 403
 404 /*
 405   initialise a chain of modules
 406  */
 407 int ldb_module_init_chain(struct ldb_context *ldb, struct ldb_module *module);
 408
 409 /*
 410  * prototype for the init function defined by dynamically loaded modules
 411  */
 412 int ldb_init_module(const char *version);
 413
 414 /* replace the components of a DN with those from another DN, without
 415  * touching the extended components
 416  *
 417  * return true if successful and false if not
 418  * if false is returned the dn may be marked invalid
 419  */
 420 bool ldb_dn_replace_components(struct ldb_dn *dn, struct ldb_dn *new_dn);
 421
 422 /*
 423   walk a parse tree, calling the provided callback on each node
 424 */
 425 int ldb_parse_tree_walk(struct ldb_parse_tree *tree,
 426                         int (*callback)(struct ldb_parse_tree *tree, void *),
 427                         void *private_context);
 428
 429 /* compare two message elements with ordering - used by modify */
 430 bool ldb_msg_element_equal_ordered(const struct ldb_message_element *el1,
 431                                    const struct ldb_message_element *el2);
 432
 433
 434 struct ldb_extended_match_rule
 435 {
 436         const char *oid;
 437         int (*callback)(struct ldb_context *, const char *oid,
 438                         const struct ldb_message *, const char *,
 439                         const struct ldb_val *, bool *);
 440 };
 441
 442 int ldb_register_extended_match_rule(struct ldb_context *ldb,
 443                                      const struct ldb_extended_match_rule *rule);
 444
 445 /*
 446  * these pack/unpack functions are exposed in the library for use by
 447  * ldb tools like ldbdump and for use in tests,
 448  * but are not part of the public API
 449  */
 450 int ldb_pack_data(struct ldb_context *ldb,
 451                   const struct ldb_message *message,
 452                   struct ldb_val *data);
 453 /*
 454  * Unpack a ldb message from a linear buffer in ldb_val
 455  *
 456  * Providing a list of attributes to this function allows selective unpacking.
 457  * Giving a NULL list (or a list_size of 0) unpacks all the attributes.
 458  */
 459 int ldb_unpack_data_only_attr_list(struct ldb_context *ldb,
 460                                    const struct ldb_val *data,
 461                                    struct ldb_message *message,
 462                                    const char* const * list,
 463                                    unsigned int list_size,
 464                                    unsigned int *nb_attributes_indb);
 465 int ldb_unpack_data(struct ldb_context *ldb,
 466                     const struct ldb_val *data,
 467                     struct ldb_message *message);
 468 /*
 469  * Unpack a ldb message from a linear buffer in ldb_val
 470  *
 471  * Providing a list of attributes to this function allows selective unpacking.
 472  * Giving a NULL list (or a list_size of 0) unpacks all the attributes.
 473  *
 474  * Flags allow control of allocation, so that if
 475  * LDB_UNPACK_DATA_FLAG_NO_DATA_ALLOC is specified, then data in values are
 476  * not allocated, instead they point into the supplier constant buffer.
 477  *
 478  * If LDB_UNPACK_DATA_FLAG_NO_VALUES_ALLOC is specified, then values
 479  * array are not allocated individually (for single-valued
 480  * attributes), instead they point into a single buffer per message.
 481  *
 482  * LDB_UNPACK_DATA_FLAG_NO_VALUES_ALLOC is only valid when
 483  * LDB_UNPACK_DATA_FLAG_NO_DATA_ALLOC is also specified.
 484  *
 485  * Likewise if LDB_UNPACK_DATA_FLAG_NO_DN is specified, the DN is omitted.
 486  */
 487 int ldb_unpack_data_only_attr_list_flags(struct ldb_context *ldb,
 488                                          const struct ldb_val *data,
 489                                          struct ldb_message *message,
 490                                          const char * const *list,
 491                                          unsigned int list_size,
 492                                          unsigned int flags,
 493                                          unsigned int *nb_elements_in_db);
 494
 495 #define LDB_UNPACK_DATA_FLAG_NO_DATA_ALLOC   0x0001
 496 #define LDB_UNPACK_DATA_FLAG_NO_DN           0x0002
 497 #define LDB_UNPACK_DATA_FLAG_NO_VALUES_ALLOC 0x0004
 498
 499 /**
 500  Forces a specific ldb handle to use the global event context.
 501
 502  This allows a nested event loop to operate, so any open
 503  transaction also needs to be aborted.
 504
 505  Any events on this event context will be lost.
 506
 507  This is used in Samba when sending an IRPC to another part of the
 508  same process instead of making a local DB modification.
 509
 510  \param handle The ldb handle to force to use the global context
 511
 512  */
 513 void ldb_handle_use_global_event_context(struct ldb_handle *handle);
 514
 515 #endif