2 * util/module.h - DNS handling module interface
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39 * This file contains the interface for DNS handling modules.
41 * The module interface uses the DNS modules as state machines. The
42 * state machines are activated in sequence to operate on queries. Once
43 * they are done, the reply is passed back. In the usual setup the mesh
44 * is the caller of the state machines and once things are done sends replies
45 * and invokes result callbacks.
47 * The module provides a number of functions, listed in the module_func_block.
48 * The module is inited and destroyed and memory usage queries, for the
49 * module as a whole, for entire-module state (such as a cache). And per-query
50 * functions are called, operate to move the state machine and cleanup of
51 * the per-query state.
53 * Most per-query state should simply be allocated in the query region.
54 * This is destroyed at the end of the query.
56 * The module environment contains services and information and caches
57 * shared by the modules and the rest of the system. It also contains
58 * function pointers for module-specific tasks (like sending queries).
60 * *** Example module calls for a normal query
62 * In this example, the query does not need recursion, all the other data
63 * can be found in the cache. This makes the example shorter.
65 * At the start of the program the iterator module is initialised.
66 * The iterator module sets up its global state, such as donotquery lists
67 * and private address trees.
69 * A query comes in, and a mesh entry is created for it. The mesh
70 * starts the resolution process. The validator module is the first
71 * in the list of modules, and it is started on this new query. The
72 * operate() function is called. The validator decides it needs not do
73 * anything yet until there is a result and returns wait_module, that
74 * causes the next module in the list to be started.
76 * The next module is the iterator. It is started on the passed query and
77 * decides to perform a lookup. For this simple example, the delegation
78 * point information is available, and all the iterator wants to do is
79 * send a UDP query. The iterator uses env.send_query() to send the
80 * query. Then the iterator suspends (returns from the operate call).
82 * When the UDP reply comes back (and on errors and timeouts), the
83 * operate function is called for the query, on the iterator module,
84 * with the event that there is a reply. The iterator decides that this
85 * is enough, the work is done. It returns the value finished from the
86 * operate call, which causes the previous module to be started.
88 * The previous module, the validator module, is started with the event
89 * that the iterator module is done. The validator decides to validate
90 * the query. Once it is done (which could take recursive lookups, but
91 * in this example no recursive lookups are needed), it returns from the
92 * operate function with finished.
94 * There is no previous module from the validator module, and the mesh
95 * takes this to mean that the query is finally done. The mesh invokes
96 * callbacks and sends packets to queriers.
98 * If other modules had been waiting (recursively) on the answer to this
99 * query, then the mesh will tell them about it. It calls the inform_super
100 * routine on all the waiting modules, and once that is done it calls all of
101 * them with the operate() call. During inform_super the query that is done
102 * still exists and information can be copied from it (but the module should
103 * not really re-entry codepoints and services). During the operate call
104 * the modules can use stored state to continue operation with the results.
105 * (network buffers are used to contain the answer packet during the
106 * inform_super phase, but after that the network buffers will be cleared
107 * of their contents so that other tasks can be performed).
109 * *** Example module calls for recursion
111 * A module is called in operate, and it decides that it wants to perform
112 * recursion. That is, it wants the full state-machine-list to operate on
113 * a different query. It calls env.attach_sub() to create a new query state.
114 * The routine returns the newly created state, and potentially the module
115 * can edit the module-states for the newly created query (i.e. pass along
116 * some information, like delegation points). The module then suspends,
117 * returns from the operate routine.
119 * The mesh meanwhile will have the newly created query (or queries) on
120 * a waiting list, and will call operate() on this query (or queries).
121 * It starts again at the start of the module list for them. The query
122 * (or queries) continue to operate their state machines, until they are
123 * done. When they are done the mesh calls inform_super on the module that
124 * wanted the recursion. After that the mesh calls operate() on the module
125 * that wanted to do the recursion, and during this phase the module could,
126 * for example, decide to create more recursions.
128 * If the module decides it no longer wants the recursive information
129 * it can call detach_subs. Those queries will still run to completion,
130 * potentially filling the cache with information. Inform_super is not
133 * The iterator module will fetch items from the cache, so a recursion
134 * attempt may complete very quickly if the item is in cache. The calling
135 * module has to wait for completion or eventual timeout. A recursive query
136 * that times out returns a servfail rcode (servfail is also returned for
137 * other errors during the lookup).
139 * Results are passed in the qstate, the rcode member is used to pass
140 * errors without requiring memory allocation, so that the code can continue
141 * in out-of-memory conditions. If the rcode member is 0 (NOERROR) then
142 * the dns_msg entry contains a filled out message. This message may
143 * also contain an rcode that is nonzero, but in this case additional
144 * information (query, additional) can be passed along.
146 * The rcode and dns_msg are used to pass the result from the the rightmost
147 * module towards the leftmost modules and then towards the user.
149 * If you want to avoid recursion-cycles where queries need other queries
150 * that need the first one, use detect_cycle() to see if that will happen.
154 #ifndef UTIL_MODULE_H
155 #define UTIL_MODULE_H
156 #include "util/storage/lruhash.h"
157 #include "util/data/msgreply.h"
158 #include "util/data/msgparse.h"
171 struct outside_network;
172 struct module_qstate;
177 struct val_neg_cache;
178 struct iter_forwards;
181 struct respip_client_info;
182 struct respip_addr_info;
184 /** Maximum number of modules in operation */
185 #define MAX_MODULE 16
187 /** Maximum number of known edns options */
188 #define MAX_KNOWN_EDNS_OPTS 256
190 struct errinf_strlist {
191 /** next item in list */
192 struct errinf_strlist* next;
193 /** config option string */
195 /** EDE code companion to the error str */
199 enum inplace_cb_list_type {
200 /* Inplace callbacks for when a resolved reply is ready to be sent to the
202 inplace_cb_reply = 0,
203 /* Inplace callbacks for when a reply is given from the cache. */
204 inplace_cb_reply_cache,
205 /* Inplace callbacks for when a reply is given with local data
206 * (or Chaos reply). */
207 inplace_cb_reply_local,
208 /* Inplace callbacks for when the reply is servfail. */
209 inplace_cb_reply_servfail,
210 /* Inplace callbacks for when a query is ready to be sent to the back.*/
212 /* Inplace callback for when a reply is received from the back. */
213 inplace_cb_query_response,
214 /* Inplace callback for when EDNS is parsed on a reply received from the
216 inplace_cb_edns_back_parsed,
217 /* Total number of types. Used for array initialization.
218 * Should always be last. */
219 inplace_cb_types_total
223 /** Known edns option. Can be populated during modules' init. */
224 struct edns_known_option {
225 /** type of this edns option */
227 /** whether the option needs to bypass the cache stage */
228 int bypass_cache_stage;
229 /** whether the option needs mesh aggregation */
234 * Inplace callback list of registered routines to be called.
238 struct inplace_cb* next;
239 /** Inplace callback routine */
247 * Inplace callback function called before replying.
248 * Called as func(qinfo, qstate, rep, rcode, edns, opt_list_out, repinfo,
249 * region, id, python_callback)
251 * qinfo: the query info.
252 * qstate: the module state. NULL when calling before the query reaches the
254 * rep: reply_info. Could be NULL.
255 * rcode: the return code.
256 * edns: the edns_data of the reply. When qstate is NULL, it is also used as
258 * opt_list_out: the edns options list for the reply.
259 * repinfo: reply information for a communication point. NULL when calling
260 * during the mesh states; the same could be found from
261 * qstate->mesh_info->reply_list.
262 * region: region to store data.
264 * python_callback: only used for registering a python callback function.
266 typedef int inplace_cb_reply_func_type(struct query_info* qinfo,
267 struct module_qstate* qstate, struct reply_info* rep, int rcode,
268 struct edns_data* edns, struct edns_option** opt_list_out,
269 struct comm_reply* repinfo, struct regional* region,
270 struct timeval* start_time, int id, void* callback);
273 * Inplace callback function called before sending the query to a nameserver.
274 * Called as func(qinfo, flags, qstate, addr, addrlen, zone, zonelen, region,
275 * id, python_callback)
278 * flags: flags of the query.
279 * qstate: query state.
280 * addr: to which server to send the query.
281 * addrlen: length of addr.
282 * zone: name of the zone of the delegation point. wireformat dname.
283 * This is the delegation point name for which the server is deemed
285 * zonelen: length of zone.
286 * region: region to store data.
288 * python_callback: only used for registering a python callback function.
290 typedef int inplace_cb_query_func_type(struct query_info* qinfo, uint16_t flags,
291 struct module_qstate* qstate, struct sockaddr_storage* addr,
292 socklen_t addrlen, uint8_t* zone, size_t zonelen, struct regional* region,
293 int id, void* callback);
296 * Inplace callback function called after parsing edns on query reply.
297 * Called as func(qstate, id, cb_args)
299 * qstate: the query state.
301 * cb_args: argument passed when registering callback.
303 typedef int inplace_cb_edns_back_parsed_func_type(struct module_qstate* qstate,
304 int id, void* cb_args);
307 * Inplace callback function called after parsing query response.
308 * Called as func(qstate, response, id, cb_args)
310 * qstate: the query state.
311 * response: query response.
313 * cb_args: argument passed when registering callback.
315 typedef int inplace_cb_query_response_func_type(struct module_qstate* qstate,
316 struct dns_msg* response, int id, void* cb_args);
319 * Function called when looking for (expired) cached answers during the serve
321 * Called as func(qstate, lookup_qinfo)
323 * qstate: the query state.
324 * lookup_qinfo: the qinfo to lookup for.
326 typedef struct dns_msg* serve_expired_lookup_func_type(
327 struct module_qstate* qstate, struct query_info* lookup_qinfo);
330 * Module environment.
331 * Services and data provided to the module.
335 /** config file with config options */
336 struct config_file* cfg;
337 /** shared message cache */
338 struct slabhash* msg_cache;
339 /** shared rrset cache */
340 struct rrset_cache* rrset_cache;
341 /** shared infrastructure cache (edns, lameness) */
342 struct infra_cache* infra_cache;
343 /** shared key cache */
344 struct key_cache* key_cache;
346 /* --- services --- */
348 * Send serviced DNS query to server. UDP/TCP and EDNS is handled.
349 * operate() should return with wait_reply. Later on a callback
350 * will cause operate() to be called with event timeout or reply.
351 * The time until a timeout is calculated from roundtrip timing,
352 * several UDP retries are attempted.
353 * @param qinfo: query info.
354 * @param flags: host order flags word, with opcode and CD bit.
355 * @param dnssec: if set, EDNS record will have bits set.
356 * If EDNS_DO bit is set, DO bit is set in EDNS records.
357 * If BIT_CD is set, CD bit is set in queries with EDNS records.
358 * @param want_dnssec: if set, the validator wants DNSSEC. Without
359 * EDNS, the answer is likely to be useless for this domain.
360 * @param nocaps: do not use caps_for_id, use the qname as given.
361 * (ignored if caps_for_id is disabled).
362 * @param check_ratelimit: if set, will check ratelimit before sending out.
363 * @param addr: where to.
364 * @param addrlen: length of addr.
365 * @param zone: delegation point name.
366 * @param zonelen: length of zone name.
367 * @param tcp_upstream: use TCP for upstream queries.
368 * @param ssl_upstream: use SSL for upstream queries.
369 * @param tls_auth_name: if ssl_upstream, use this name with TLS
371 * @param q: which query state to reactivate upon return.
372 * @param was_ratelimited: it will signal back if the query failed to pass the
374 * @return: false on failure (memory or socket related). no query was
375 * sent. Or returns an outbound entry with qsent and qstate set.
376 * This outbound_entry will be used on later module invocations
377 * that involve this query (timeout, error or reply).
379 struct outbound_entry* (*send_query)(struct query_info* qinfo,
380 uint16_t flags, int dnssec, int want_dnssec, int nocaps,
382 struct sockaddr_storage* addr, socklen_t addrlen,
383 uint8_t* zone, size_t zonelen, int tcp_upstream, int ssl_upstream,
384 char* tls_auth_name, struct module_qstate* q, int* was_ratelimited);
388 * Remove all sub-query references from this query state.
389 * Keeps super-references of those sub-queries correct.
390 * Updates stat items in mesh_area structure.
391 * @param qstate: used to find mesh state.
393 void (*detach_subs)(struct module_qstate* qstate);
397 * Creates it if it does not exist already.
398 * Keeps sub and super references correct.
399 * Updates stat items in mesh_area structure.
400 * Pass if it is priming query or not.
402 * o if error (malloc) happened.
403 * o need to initialise the new state (module init; it is a new state).
404 * so that the next run of the query with this module is successful.
405 * o no init needed, attachment successful.
407 * @param qstate: the state to find mesh state, and that wants to
408 * receive the results from the new subquery.
409 * @param qinfo: what to query for (copied).
410 * @param qflags: what flags to use (RD, CD flag or not).
411 * @param prime: if it is a (stub) priming query.
412 * @param valrec: validation lookup recursion, does not need validation
413 * @param newq: If the new subquery needs initialisation, it is
414 * returned, otherwise NULL is returned.
415 * @return: false on error, true if success (and init may be needed).
417 int (*attach_sub)(struct module_qstate* qstate,
418 struct query_info* qinfo, uint16_t qflags, int prime,
419 int valrec, struct module_qstate** newq);
422 * Add detached query.
423 * Creates it if it does not exist already.
424 * Does not make super/sub references.
425 * Performs a cycle detection - for double check - and fails if there is
427 * Updates stat items in mesh_area structure.
428 * Pass if it is priming query or not.
430 * o if error (malloc) happened.
431 * o need to initialise the new state (module init; it is a new state).
432 * so that the next run of the query with this module is successful.
433 * o no init needed, attachment successful.
434 * o added subquery, created if it did not exist already.
436 * @param qstate: the state to find mesh state, and that wants to receive
437 * the results from the new subquery.
438 * @param qinfo: what to query for (copied).
439 * @param qflags: what flags to use (RD / CD flag or not).
440 * @param prime: if it is a (stub) priming query.
441 * @param valrec: if it is a validation recursion query (lookup of key, DS).
442 * @param newq: If the new subquery needs initialisation, it is returned,
443 * otherwise NULL is returned.
444 * @param sub: The added mesh state, created if it did not exist already.
445 * @return: false on error, true if success (and init may be needed).
447 int (*add_sub)(struct module_qstate* qstate,
448 struct query_info* qinfo, uint16_t qflags, int prime,
449 int valrec, struct module_qstate** newq,
450 struct mesh_state** sub);
453 * Kill newly attached sub. If attach_sub returns newq for
454 * initialisation, but that fails, then this routine will cleanup and
455 * delete the freshly created sub.
456 * @param newq: the new subquery that is no longer needed.
459 void (*kill_sub)(struct module_qstate* newq);
462 * Detect if adding a dependency for qstate on name,type,class will
463 * create a dependency cycle.
464 * @param qstate: given mesh querystate.
465 * @param qinfo: query info for dependency.
466 * @param flags: query flags of dependency, RD/CD flags.
467 * @param prime: if dependency is a priming query or not.
468 * @param valrec: validation lookup recursion, does not need validation
469 * @return true if the name,type,class exists and the given
470 * qstate mesh exists as a dependency of that name. Thus
471 * if qstate becomes dependent on name,type,class then a
474 int (*detect_cycle)(struct module_qstate* qstate,
475 struct query_info* qinfo, uint16_t flags, int prime,
478 /** region for temporary usage. May be cleared after operate() call. */
479 struct regional* scratch;
480 /** buffer for temporary usage. May be cleared after operate() call. */
481 struct sldns_buffer* scratch_buffer;
482 /** internal data for daemon - worker thread. */
483 struct worker* worker;
484 /** the worker event base */
485 struct comm_base* worker_base;
486 /** the outside network */
487 struct outside_network* outnet;
488 /** mesh area with query state dependencies */
489 struct mesh_area* mesh;
490 /** allocation service */
491 struct alloc_cache* alloc;
492 /** random table to generate random numbers */
493 struct ub_randstate* rnd;
494 /** time in seconds, converted to integer */
496 /** time in microseconds. Relatively recent. */
497 struct timeval* now_tv;
498 /** is validation required for messages, controls client-facing
499 * validation status (AD bits) and servfails */
500 int need_to_validate;
501 /** trusted key storage; these are the configured keys, if not NULL,
502 * otherwise configured by validator. These are the trust anchors,
503 * and are not primed and ready for validation, but on the bright
504 * side, they are read only memory, thus no locks and fast. */
505 struct val_anchors* anchors;
506 /** negative cache, configured by the validator. if not NULL,
507 * contains NSEC record lookup trees. */
508 struct val_neg_cache* neg_cache;
509 /** the 5011-probe timer (if any) */
510 struct comm_timer* probe_timer;
512 struct auth_zones* auth_zones;
513 /** Mapping of forwarding zones to targets.
514 * iterator forwarder information. per-thread, created by worker */
515 struct iter_forwards* fwds;
517 * iterator forwarder information. per-thread, created by worker.
518 * The hints -- these aren't stored in the cache because they don't
519 * expire. The hints are always used to "prime" the cache. Note
520 * that both root hints and stub zone "hints" are stored in this
523 struct iter_hints* hints;
524 /** module specific data. indexed by module id. */
525 void* modinfo[MAX_MODULE];
527 /* Shared linked list of inplace callback functions */
528 struct inplace_cb* inplace_cb_lists[inplace_cb_types_total];
531 * Shared array of known edns options (size MAX_KNOWN_EDNS_OPTS).
532 * Filled by edns literate modules during init.
534 struct edns_known_option* edns_known_options;
535 /* Number of known edns options */
536 size_t edns_known_options_num;
537 /** EDNS client string information */
538 struct edns_strings* edns_strings;
540 /* Make every mesh state unique, do not aggregate mesh states. */
545 * External visible states of the module state machine
546 * Modules may also have an internal state.
547 * Modules are supposed to run to completion or until blocked.
549 enum module_ext_state {
550 /** initial state - new query */
551 module_state_initial = 0,
552 /** waiting for reply to outgoing network query */
554 /** module is waiting for another module */
556 /** module is waiting for another module; that other is restarted */
558 /** module is waiting for sub-query */
559 module_wait_subquery,
560 /** module could not finish the query */
562 /** module is finished with query */
567 * Events that happen to modules, that start or wakeup modules.
571 module_event_new = 0,
572 /** query passed by other module */
574 /** reply inbound from server */
576 /** no reply, timeout or other error */
577 module_event_noreply,
578 /** reply is there, but capitalisation check failed */
579 module_event_capsfail,
580 /** next module is done, and its reply is awaiting you */
581 module_event_moddone,
587 * Linked list of sockaddrs
588 * May be allocated such that only 'len' bytes of addr exist for the structure.
592 struct sock_list* next;
593 /** length of addr */
596 struct sockaddr_storage addr;
599 struct respip_action_info;
602 * Struct to hold relevant data for serve expired
604 struct serve_expired_data {
605 struct comm_timer* timer;
606 serve_expired_lookup_func_type* get_cached_answer;
610 * Module state, per query.
612 struct module_qstate {
613 /** which query is being answered: name, type, class */
614 struct query_info qinfo;
615 /** flags uint16 from query */
616 uint16_t query_flags;
617 /** if this is a (stub or root) priming query (with hints) */
619 /** if this is a validation recursion query that does not get
620 * validation itself */
623 /** the client network address is needed for the client-subnet option
624 * when prefetching, but we can't use reply_list in mesh_info, because
625 * we don't want to send a reply for the internal query. */
626 struct sockaddr_storage client_addr;
629 /** comm_reply contains server replies */
630 struct comm_reply* reply;
631 /** the reply message, with message for client and calling module */
632 struct dns_msg* return_msg;
633 /** the rcode, in case of error, instead of a reply message */
635 /** origin of the reply (can be NULL from cache, list for cnames) */
636 struct sock_list* reply_origin;
637 /** IP blacklist for queries */
638 struct sock_list* blacklist;
639 /** region for this query. Cleared when query process finishes. */
640 struct regional* region;
641 /** failure reason information if val-log-level is high */
642 struct errinf_strlist* errinf;
643 /** which module is executing */
646 enum module_ext_state ext_state[MAX_MODULE];
647 /** module specific data for query. indexed by module id. */
648 void* minfo[MAX_MODULE];
649 /** environment for this query */
650 struct module_env* env;
651 /** mesh related information for this query */
652 struct mesh_state* mesh_info;
653 /** how many seconds before expiry is this prefetched (0 if not) */
654 time_t prefetch_leeway;
655 /** serve expired data */
656 struct serve_expired_data* serve_expired_data;
658 /** incoming edns options from the front end */
659 struct edns_option* edns_opts_front_in;
660 /** outgoing edns options to the back end */
661 struct edns_option* edns_opts_back_out;
662 /** incoming edns options from the back end */
663 struct edns_option* edns_opts_back_in;
664 /** outgoing edns options to the front end */
665 struct edns_option* edns_opts_front_out;
666 /** whether modules should answer from the cache */
668 /** whether modules should store answer in the cache */
670 /** whether to refetch a fresh answer on finishing this state*/
672 /** whether the query (or a subquery) was ratelimited */
674 /** time when query was started. This is when the qstate is created.
675 * This is used so that type NS data cannot be overwritten by them
676 * expiring while the lookup is in progress, using data fetched from
677 * those servers. By comparing expiry time with qstarttime for type NS.
680 /** whether a message from cachedb will be used for the reply */
681 int is_cachedb_answer;
684 * Attributes of clients that share the qstate that may affect IP-based
687 struct respip_client_info* client_info;
689 /** Extended result of response-ip action processing, mainly
690 * for logging purposes. */
691 struct respip_action_info* respip_action_info;
692 /** if the query is rpz passthru, no further rpz processing for it */
694 /* Flag tcp required. */
697 /** whether the reply should be dropped */
702 * Module functionality block
704 struct module_func_block {
705 /** text string name of module */
709 * init the module. Called once for the global state.
710 * This is the place to apply settings from the config file.
711 * @param env: module environment.
712 * @param id: module id number.
715 int (*init)(struct module_env* env, int id);
718 * de-init, delete, the module. Called once for the global state.
719 * @param env: module environment.
720 * @param id: module id number.
722 void (*deinit)(struct module_env* env, int id);
725 * accept a new query, or work further on existing query.
726 * Changes the qstate->ext_state to be correct on exit.
727 * @param ev: event that causes the module state machine to
729 * @param qstate: the query state.
730 * Note that this method is not allowed to change the
731 * query state 'identity', that is query info, qflags,
732 * and priming status.
733 * Attach a subquery to get results to a different query.
734 * @param id: module id number that operate() is called on.
735 * @param outbound: if not NULL this event is due to the reply/timeout
736 * or error on this outbound query.
737 * @return: if at exit the ext_state is:
738 * o wait_module: next module is started. (with pass event).
739 * o error or finished: previous module is resumed.
740 * o otherwise it waits until that event happens (assumes
741 * the service routine to make subrequest or send message
744 void (*operate)(struct module_qstate* qstate, enum module_ev event,
745 int id, struct outbound_entry* outbound);
748 * inform super querystate about the results from this subquerystate.
749 * Is called when the querystate is finished. The method invoked is
750 * the one from the current module active in the super querystate.
751 * @param qstate: the query state that is finished.
752 * Examine return_rcode and return_reply in the qstate.
753 * @param id: module id for this module.
754 * This coincides with the current module for the super qstate.
755 * @param super: the super querystate that needs to be informed.
757 void (*inform_super)(struct module_qstate* qstate, int id,
758 struct module_qstate* super);
761 * clear module specific data
763 void (*clear)(struct module_qstate* qstate, int id);
766 * How much memory is the module specific data using.
767 * @param env: module environment.
768 * @param id: the module id.
769 * @return the number of bytes that are alloced.
771 size_t (*get_mem)(struct module_env* env, int id);
775 * Debug utility: module external qstate to string
776 * @param s: the state value.
777 * @return descriptive string.
779 const char* strextstate(enum module_ext_state s);
782 * Debug utility: module event to string
783 * @param e: the module event value.
784 * @return descriptive string.
786 const char* strmodulevent(enum module_ev e);
789 * Append text to the error info for validation.
790 * @param qstate: query state.
791 * @param str: copied into query region and appended.
792 * Failures to allocate are logged.
794 void errinf(struct module_qstate* qstate, const char* str);
795 void errinf_ede(struct module_qstate* qstate, const char* str,
796 sldns_ede_code reason_bogus);
799 * Append text to error info: from 1.2.3.4
800 * @param qstate: query state.
801 * @param origin: sock list with origin of trouble.
802 * Every element added.
803 * If NULL: nothing is added.
804 * if 0len element: 'from cache' is added.
806 void errinf_origin(struct module_qstate* qstate, struct sock_list *origin);
809 * Append text to error info: for RRset name type class
810 * @param qstate: query state.
811 * @param rr: rrset_key.
813 void errinf_rrset(struct module_qstate* qstate, struct ub_packed_rrset_key *rr);
816 * Append text to error info: str dname
817 * @param qstate: query state.
818 * @param str: explanation string
819 * @param dname: the dname.
821 void errinf_dname(struct module_qstate* qstate, const char* str,
825 * Create error info in string. For validation failures.
826 * @param qstate: query state.
827 * @return string or NULL on malloc failure (already logged).
828 * This string is malloced and has to be freed by caller.
830 char* errinf_to_str_bogus(struct module_qstate* qstate);
833 * Check the sldns_ede_code of the qstate->errinf.
834 * @param qstate: query state.
835 * @return the latest explicitly set sldns_ede_code or LDNS_EDE_NONE.
837 sldns_ede_code errinf_to_reason_bogus(struct module_qstate* qstate);
840 * Create error info in string. For other servfails.
841 * @param qstate: query state.
842 * @return string or NULL on malloc failure (already logged).
843 * This string is malloced and has to be freed by caller.
845 char* errinf_to_str_servfail(struct module_qstate* qstate);
848 * Create error info in string. For misc failures that are not servfail.
849 * @param qstate: query state.
850 * @return string or NULL on malloc failure (already logged).
851 * This string is malloced and has to be freed by caller.
853 char* errinf_to_str_misc(struct module_qstate* qstate);
856 * Initialize the edns known options by allocating the required space.
857 * @param env: the module environment.
858 * @return false on failure (no memory).
860 int edns_known_options_init(struct module_env* env);
863 * Free the allocated space for the known edns options.
864 * @param env: the module environment.
866 void edns_known_options_delete(struct module_env* env);
869 * Register a known edns option. Overwrite the flags if it is already
870 * registered. Used before creating workers to register known edns options.
871 * @param opt_code: the edns option code.
872 * @param bypass_cache_stage: whether the option interacts with the cache.
873 * @param no_aggregation: whether the option implies more specific
875 * @param env: the module environment.
876 * @return true on success, false on failure (registering more options than
877 * allowed or trying to register after the environment is copied to the
880 int edns_register_option(uint16_t opt_code, int bypass_cache_stage,
881 int no_aggregation, struct module_env* env);
884 * Register an inplace callback function.
885 * @param cb: pointer to the callback function.
886 * @param type: inplace callback type.
887 * @param cbarg: argument for the callback function, or NULL.
888 * @param env: the module environment.
889 * @param id: module id.
890 * @return true on success, false on failure (out of memory or trying to
891 * register after the environment is copied to the threads.)
894 inplace_cb_register(void* cb, enum inplace_cb_list_type type, void* cbarg,
895 struct module_env* env, int id);
898 * Delete callback for specified type and module id.
899 * @param env: the module environment.
900 * @param type: inplace callback type.
901 * @param id: module id.
904 inplace_cb_delete(struct module_env* env, enum inplace_cb_list_type type,
908 * Delete all the inplace callback linked lists.
909 * @param env: the module environment.
911 void inplace_cb_lists_delete(struct module_env* env);
914 * Check if an edns option is known.
915 * @param opt_code: the edns option code.
916 * @param env: the module environment.
917 * @return pointer to registered option if the edns option is known,
920 struct edns_known_option* edns_option_is_known(uint16_t opt_code,
921 struct module_env* env);
924 * Check if an edns option needs to bypass the reply from cache stage.
925 * @param list: the edns options.
926 * @param env: the module environment.
927 * @return true if an edns option needs to bypass the cache stage,
930 int edns_bypass_cache_stage(struct edns_option* list,
931 struct module_env* env);
934 * Check if an unique mesh state is required. Might be triggered by EDNS option
935 * or set for the complete env.
936 * @param list: the edns options.
937 * @param env: the module environment.
938 * @return true if an edns option needs a unique mesh state,
941 int unique_mesh_state(struct edns_option* list, struct module_env* env);
944 * Log the known edns options.
945 * @param level: the desired verbosity level.
946 * @param env: the module environment.
948 void log_edns_known_options(enum verbosity_value level,
949 struct module_env* env);
952 * Copy state that may have happened in the subquery and is always relevant to
954 * @param qstate: query state that finished.
955 * @param id: module id.
956 * @param super: the qstate to inform.
958 void copy_state_to_super(struct module_qstate* qstate, int id,
959 struct module_qstate* super);
961 #endif /* UTIL_MODULE_H */