xref: /freebsd/contrib/unbound/services/localzone.h (revision 2008043f386721d58158e37e0d7e50df8095942d)
1 /*
2  * services/localzone.h - local zones authority service.
3  *
4  * Copyright (c) 2007, NLnet Labs. All rights reserved.
5  *
6  * This software is open source.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * Redistributions of source code must retain the above copyright notice,
13  * this list of conditions and the following disclaimer.
14  *
15  * Redistributions in binary form must reproduce the above copyright notice,
16  * this list of conditions and the following disclaimer in the documentation
17  * and/or other materials provided with the distribution.
18  *
19  * Neither the name of the NLNET LABS nor the names of its contributors may
20  * be used to endorse or promote products derived from this software without
21  * specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
24  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
25  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
26  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
27  * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
28  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
29  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
30  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
31  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
32  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
33  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34  */
35 
36 /**
37  * \file
38  *
39  * This file contains functions to enable local zone authority service.
40  */
41 
42 #ifndef SERVICES_LOCALZONE_H
43 #define SERVICES_LOCALZONE_H
44 #include "util/rbtree.h"
45 #include "util/locks.h"
46 #include "util/storage/dnstree.h"
47 #include "util/module.h"
48 #include "services/view.h"
49 #include "sldns/sbuffer.h"
50 struct packed_rrset_data;
51 struct ub_packed_rrset_key;
52 struct regional;
53 struct config_file;
54 struct edns_data;
55 struct query_info;
56 struct sldns_buffer;
57 struct comm_reply;
58 struct config_strlist;
59 
60 /**
61  * Local zone type
62  * This type determines processing for queries that did not match
63  * local-data directly.
64  */
65 enum localzone_type {
66 	/** unset type, used for unset tag_action elements */
67 	local_zone_unset = 0,
68 	/** drop query */
69 	local_zone_deny,
70 	/** answer with error */
71 	local_zone_refuse,
72 	/** answer nxdomain or nodata */
73 	local_zone_static,
74 	/** resolve normally */
75 	local_zone_transparent,
76 	/** do not block types at localdata names */
77 	local_zone_typetransparent,
78 	/** answer with data at zone apex */
79 	local_zone_redirect,
80 	/** remove default AS112 blocking contents for zone
81 	 * nodefault is used in config not during service. */
82 	local_zone_nodefault,
83 	/** log client address, but no block (transparent) */
84 	local_zone_inform,
85 	/** log client address, and block (drop) */
86 	local_zone_inform_deny,
87 	/** log client address, and direct */
88 	local_zone_inform_redirect,
89 	/** resolve normally, even when there is local data */
90 	local_zone_always_transparent,
91 	/** resolve normally, even when there is local data but return NODATA for A queries */
92 	local_zone_block_a,
93 	/** answer with error, even when there is local data */
94 	local_zone_always_refuse,
95 	/** answer with nxdomain, even when there is local data */
96 	local_zone_always_nxdomain,
97 	/** answer with noerror/nodata, even when there is local data */
98 	local_zone_always_nodata,
99 	/** drop query, even when there is local data */
100 	local_zone_always_deny,
101 	/** answer with 0.0.0.0 or ::0 or noerror/nodata, even when there is
102 	 * local data */
103 	local_zone_always_null,
104 	/** answer not from the view, but global or no-answer */
105 	local_zone_noview,
106 	/** truncate the response; client should retry via tcp */
107 	local_zone_truncate,
108 	/** Invalid type, cannot be used to generate answer */
109 	local_zone_invalid
110 };
111 
112 /**
113  * Authoritative local zones storage, shared.
114  */
115 struct local_zones {
116 	/** lock on the localzone tree */
117 	lock_rw_type lock;
118 	/** rbtree of struct local_zone */
119 	rbtree_type ztree;
120 };
121 
122 /**
123  * Local zone. A locally served authoritative zone.
124  */
125 struct local_zone {
126 	/** rbtree node, key is name and class */
127 	rbnode_type node;
128 	/** parent zone, if any. */
129 	struct local_zone* parent;
130 
131 	/** zone name, in uncompressed wireformat */
132 	uint8_t* name;
133 	/** length of zone name */
134 	size_t namelen;
135 	/** number of labels in zone name */
136 	int namelabs;
137 	/** the class of this zone.
138 	 * uses 'dclass' to not conflict with c++ keyword class. */
139 	uint16_t dclass;
140 
141 	/** lock on the data in the structure
142 	 * For the node, parent, name, namelen, namelabs, dclass, you
143 	 * need to also hold the zones_tree lock to change them (or to
144 	 * delete this zone) */
145 	lock_rw_type lock;
146 
147 	/** how to process zone */
148 	enum localzone_type type;
149 	/** tag bitlist */
150 	uint8_t* taglist;
151 	/** length of the taglist (in bytes) */
152 	size_t taglen;
153 	/** netblock addr_tree with struct local_zone_override information
154 	 * or NULL if there are no override elements */
155 	struct rbtree_type* override_tree;
156 
157 	/** in this region the zone's data is allocated.
158 	 * the struct local_zone itself is malloced. */
159 	struct regional* region;
160 	/** local data for this zone
161 	 * rbtree of struct local_data */
162 	rbtree_type data;
163 	/** if data contains zone apex SOA data, this is a ptr to it. */
164 	struct ub_packed_rrset_key* soa;
165 	/** if data contains zone apex SOA data, this is a ptr to an
166 	 * artificial negative SOA rrset (TTL is the minimum of the TTL and the
167 	 * SOA.MINIMUM). */
168 	struct ub_packed_rrset_key* soa_negative;
169 };
170 
171 /**
172  * Local data. One domain name, and the RRs to go with it.
173  */
174 struct local_data {
175 	/** rbtree node, key is name only */
176 	rbnode_type node;
177 	/** domain name */
178 	uint8_t* name;
179 	/** length of name */
180 	size_t namelen;
181 	/** number of labels in name */
182 	int namelabs;
183 	/** the data rrsets, with different types, linked list.
184 	 * If this list is NULL, the node is an empty non-terminal. */
185 	struct local_rrset* rrsets;
186 };
187 
188 /**
189  * A local data RRset
190  */
191 struct local_rrset {
192 	/** next in list */
193 	struct local_rrset* next;
194 	/** RRset data item */
195 	struct ub_packed_rrset_key* rrset;
196 };
197 
198 /**
199  * Local zone override information
200  */
201 struct local_zone_override {
202 	/** node in addrtree */
203 	struct addr_tree_node node;
204 	/** override for local zone type */
205 	enum localzone_type type;
206 };
207 
208 /**
209  * Create local zones storage
210  * @return new struct or NULL on error.
211  */
212 struct local_zones* local_zones_create(void);
213 
214 /**
215  * Delete local zones storage
216  * @param zones: to delete.
217  */
218 void local_zones_delete(struct local_zones* zones);
219 
220 /**
221  * Apply config settings; setup the local authoritative data.
222  * Takes care of locking.
223  * @param zones: is set up.
224  * @param cfg: config data.
225  * @return false on error.
226  */
227 int local_zones_apply_cfg(struct local_zones* zones, struct config_file* cfg);
228 
229 /**
230  * Compare two local_zone entries in rbtree. Sort hierarchical but not
231  * canonical
232  * @param z1: zone 1
233  * @param z2: zone 2
234  * @return: -1, 0, +1 comparison value.
235  */
236 int local_zone_cmp(const void* z1, const void* z2);
237 
238 /**
239  * Compare two local_data entries in rbtree. Sort canonical.
240  * @param d1: data 1
241  * @param d2: data 2
242  * @return: -1, 0, +1 comparison value.
243  */
244 int local_data_cmp(const void* d1, const void* d2);
245 
246 /**
247  * Delete one zone
248  * @param z: to delete.
249  */
250 void local_zone_delete(struct local_zone* z);
251 
252 /**
253  * Lookup zone that contains the given name, class and taglist.
254  * User must lock the tree or result zone.
255  * @param zones: the zones tree
256  * @param name: dname to lookup
257  * @param len: length of name.
258  * @param labs: labelcount of name.
259  * @param dclass: class to lookup.
260  * @param dtype: type to lookup, if type DS a zone higher is used for zonecuts.
261  * @param taglist: taglist to lookup.
262  * @param taglen: length of taglist.
263  * @param ignoretags: lookup zone by name and class, regardless the
264  * local-zone's tags.
265  * @return closest local_zone or NULL if no covering zone is found.
266  */
267 struct local_zone* local_zones_tags_lookup(struct local_zones* zones,
268 	uint8_t* name, size_t len, int labs, uint16_t dclass, uint16_t dtype,
269 	uint8_t* taglist, size_t taglen, int ignoretags);
270 
271 /**
272  * Lookup zone that contains the given name, class.
273  * User must lock the tree or result zone.
274  * @param zones: the zones tree
275  * @param name: dname to lookup
276  * @param len: length of name.
277  * @param labs: labelcount of name.
278  * @param dclass: class to lookup.
279  * @param dtype: type of the record, if type DS then a zone higher up is found
280  *   pass 0 to just plain find a zone for a name.
281  * @return closest local_zone or NULL if no covering zone is found.
282  */
283 struct local_zone* local_zones_lookup(struct local_zones* zones,
284 	uint8_t* name, size_t len, int labs, uint16_t dclass, uint16_t dtype);
285 
286 /**
287  * Debug helper. Print all zones
288  * Takes care of locking.
289  * @param zones: the zones tree
290  */
291 void local_zones_print(struct local_zones* zones);
292 
293 /**
294  * Answer authoritatively for local zones.
295  * Takes care of locking.
296  * @param zones: the stored zones (shared, read only).
297  * @param env: the module environment.
298  * @param qinfo: query info (parsed).
299  * @param edns: edns info (parsed).
300  * @param buf: buffer with query ID and flags, also for reply.
301  * @param temp: temporary storage region.
302  * @param repinfo: source address for checks. may be NULL.
303  * @param taglist: taglist for checks. May be NULL.
304  * @param taglen: length of the taglist.
305  * @param tagactions: local zone actions for tags. May be NULL.
306  * @param tagactionssize: length of the tagactions.
307  * @param tag_datas: array per tag of strlist with rdata strings. or NULL.
308  * @param tag_datas_size: size of tag_datas array.
309  * @param tagname: array of tag name strings (for debug output).
310  * @param num_tags: number of items in tagname array.
311  * @param view: answer using this view. May be NULL.
312  * @return true if answer is in buffer. false if query is not answered
313  * by authority data. If the reply should be dropped altogether, the return
314  * value is true, but the buffer is cleared (empty).
315  * It can also return true if a non-exact alias answer is found.  In this
316  * case qinfo->local_alias points to the corresponding alias RRset but the
317  * answer is NOT encoded in buffer.  It's the caller's responsibility to
318  * complete the alias chain (if needed) and encode the final set of answer.
319  * Data pointed to by qinfo->local_alias is allocated in 'temp' or refers to
320  * configuration data.  So the caller will need to make a deep copy of it
321  * if it needs to keep it beyond the lifetime of 'temp' or a dynamic update
322  * to local zone data.
323  */
324 int local_zones_answer(struct local_zones* zones, struct module_env* env,
325 	struct query_info* qinfo, struct edns_data* edns, struct sldns_buffer* buf,
326 	struct regional* temp, struct comm_reply* repinfo, uint8_t* taglist,
327 	size_t taglen, uint8_t* tagactions, size_t tagactionssize,
328 	struct config_strlist** tag_datas, size_t tag_datas_size,
329 	char** tagname, int num_tags, struct view* view);
330 
331 /**
332  * Answer using the local zone only (not local data used).
333  * @param z: zone for query.
334  * @param env: module environment.
335  * @param qinfo: query.
336  * @param edns: edns from query.
337  * @param repinfo: source address for checks. may be NULL.
338  * @param buf: buffer for answer.
339  * @param temp: temp region for encoding.
340  * @param ld: local data, if NULL, no such name exists in localdata.
341  * @param lz_type: type of the local zone.
342  * @return 1 if a reply is to be sent, 0 if not.
343  */
344 int
345 local_zones_zone_answer(struct local_zone* z, struct module_env* env,
346 	struct query_info* qinfo, struct edns_data* edns,
347 	struct comm_reply* repinfo, sldns_buffer* buf, struct regional* temp,
348 	struct local_data* ld, enum localzone_type lz_type);
349 
350 /**
351  * Parse the string into localzone type.
352  *
353  * @param str: string to parse
354  * @param t: local zone type returned here.
355  * @return 0 on parse error.
356  */
357 int local_zone_str2type(const char* str, enum localzone_type* t);
358 
359 /**
360  * Print localzone type to a string.  Pointer to a constant string.
361  *
362  * @param t: local zone type.
363  * @return constant string that describes type.
364  */
365 const char* local_zone_type2str(enum localzone_type t);
366 
367 /**
368  * Find zone that with exactly given name, class.
369  * User must lock the tree or result zone.
370  * @param zones: the zones tree
371  * @param name: dname to lookup
372  * @param len: length of name.
373  * @param labs: labelcount of name.
374  * @param dclass: class to lookup.
375  * @return the exact local_zone or NULL.
376  */
377 struct local_zone* local_zones_find(struct local_zones* zones,
378 	uint8_t* name, size_t len, int labs, uint16_t dclass);
379 
380 /**
381  * Find zone that with exactly or smaller name/class
382  * User must lock the tree or result zone.
383  * @param zones: the zones tree
384  * @param name: dname to lookup
385  * @param len: length of name.
386  * @param labs: labelcount of name.
387  * @param dclass: class to lookup.
388  * @param exact: 1 on return is this is an exact match.
389  * @return the exact or smaller local_zone or NULL.
390  */
391 struct local_zone*
392 local_zones_find_le(struct local_zones* zones,
393         uint8_t* name, size_t len, int labs, uint16_t dclass,
394 	int* exact);
395 
396 /**
397  * Add a new zone. Caller must hold the zones lock.
398  * Adjusts the other zones as well (parent pointers) after insertion.
399  * The zone must NOT exist (returns NULL and logs error).
400  * @param zones: the zones tree
401  * @param name: dname to add
402  * @param len: length of name.
403  * @param labs: labelcount of name.
404  * @param dclass: class to add.
405  * @param tp: type.
406  * @return local_zone or NULL on error, caller must printout memory error.
407  */
408 struct local_zone* local_zones_add_zone(struct local_zones* zones,
409 	uint8_t* name, size_t len, int labs, uint16_t dclass,
410 	enum localzone_type tp);
411 
412 /**
413  * Delete a zone. Caller must hold the zones lock.
414  * Adjusts the other zones as well (parent pointers) after insertion.
415  * @param zones: the zones tree
416  * @param zone: the zone to delete from tree. Also deletes zone from memory.
417  */
418 void local_zones_del_zone(struct local_zones* zones, struct local_zone* zone);
419 
420 /**
421  * Add RR data into the localzone data.
422  * Looks up the zone, if no covering zone, a transparent zone with the
423  * name of the RR is created.
424  * @param zones: the zones tree. Not locked by caller.
425  * @param rr: string with on RR.
426  * @return false on failure.
427  */
428 int local_zones_add_RR(struct local_zones* zones, const char* rr);
429 
430 /**
431  * Remove data from domain name in the tree.
432  * All types are removed. No effect if zone or name does not exist.
433  * @param zones: zones tree.
434  * @param name: dname to remove
435  * @param len: length of name.
436  * @param labs: labelcount of name.
437  * @param dclass: class to remove.
438  */
439 void local_zones_del_data(struct local_zones* zones,
440 	uint8_t* name, size_t len, int labs, uint16_t dclass);
441 
442 
443 /**
444  * Form wireformat from text format domain name.
445  * @param str: the domain name in text "www.example.com"
446  * @param res: resulting wireformat is stored here with malloc.
447  * @param len: length of resulting wireformat.
448  * @param labs: number of labels in resulting wireformat.
449  * @return false on error, syntax or memory. Also logged.
450  */
451 int parse_dname(const char* str, uint8_t** res, size_t* len, int* labs);
452 
453 /**
454  * Find local data tag string match for the given type (in qinfo) in the list.
455  * If found, 'r' will be filled with corresponding rrset information.
456  * @param qinfo: contains name, type, and class for the data
457  * @param list: stores local tag data to be searched
458  * @param r: rrset key to be filled for matched data
459  * @param temp: region to allocate rrset in 'r'
460  * @return 1 if a match is found and rrset is built; otherwise 0 including
461  * errors.
462  */
463 int local_data_find_tag_datas(const struct query_info* qinfo,
464 	struct config_strlist* list, struct ub_packed_rrset_key* r,
465 	struct regional* temp);
466 
467 /**
468  * See if two sets of tag lists (in the form of bitmap) have the same tag that
469  * has an action.  If so, '*tag' will be set to the found tag index, and the
470  * corresponding action will be returned in the form of local zone type.
471  * Otherwise the passed type (lzt) will be returned as the default action.
472  * Pointers except tagactions must not be NULL.
473  * @param taglist: 1st list of tags
474  * @param taglen: size of taglist in bytes
475  * @param taglist2: 2nd list of tags
476  * @param taglen2: size of taglist2 in bytes
477  * @param tagactions: local data actions for tags. May be NULL.
478  * @param tagactionssize: length of the tagactions.
479  * @param lzt: default action (local zone type) if no tag action is found.
480  * @param tag: see above.
481  * @param tagname: array of tag name strings (for debug output).
482  * @param num_tags: number of items in tagname array.
483  * @return found tag action or the default action.
484  */
485 enum localzone_type local_data_find_tag_action(const uint8_t* taglist,
486 	size_t taglen, const uint8_t* taglist2, size_t taglen2,
487 	const uint8_t* tagactions, size_t tagactionssize,
488 	enum localzone_type lzt, int* tag, char* const* tagname, int num_tags);
489 
490 /**
491  * Enter defaults to local zone.
492  * @param zones: to add defaults to
493  * @param cfg: containing list of zones to exclude from default set.
494  * @return 1 on success; 0 otherwise.
495  */
496 int local_zone_enter_defaults(struct local_zones* zones,
497 	struct config_file* cfg);
498 
499 /**
500   * Parses resource record string into wire format, also returning its field values.
501   * @param str: input resource record
502   * @param nm: domain name field
503   * @param type: record type field
504   * @param dclass: record class field
505   * @param ttl: ttl field
506   * @param rr: buffer for the parsed rr in wire format
507   * @param len: buffer length
508   * @param rdata: rdata field
509   * @param rdata_len: rdata field length
510   * @return 1 on success; 0 otherwise.
511   */
512 int rrstr_get_rr_content(const char* str, uint8_t** nm, uint16_t* type,
513 	uint16_t* dclass, time_t* ttl, uint8_t* rr, size_t len,
514 	uint8_t** rdata, size_t* rdata_len);
515 
516 /**
517   * Insert specified rdata into the specified resource record.
518   * @param region: allocator
519   * @param pd: data portion of the destination resource record
520   * @param rdata: source rdata
521   * @param rdata_len: source rdata length
522   * @param ttl: time to live
523   * @param rrstr: resource record in text form (for logging)
524   * @return 1 on success; 0 otherwise.
525   */
526 int rrset_insert_rr(struct regional* region, struct packed_rrset_data* pd,
527 	uint8_t* rdata, size_t rdata_len, time_t ttl, const char* rrstr);
528 
529 /**
530  * Remove RR from rrset that is created using localzone's rrset_insert_rr.
531  * @param pd: the RRset containing the RR to remove
532  * @param index: index of RR to remove
533  * @return: 1 on success; 0 otherwise.
534  */
535 int
536 local_rrset_remove_rr(struct packed_rrset_data* pd, size_t index);
537 
538 /**
539   * Valid response ip actions for the IP-response-driven-action feature;
540   * defined here instead of in the respip module to enable sharing of enum
541   * values with the localzone_type enum.
542   * Note that these values except 'none' are the same as localzone types of
543   * the 'same semantics'.  It's intentional as we use these values via
544   * access-control-tags, which can be shared for both response ip actions and
545   * local zones.
546   */
547 enum respip_action {
548 	/** no respip action */
549 	respip_none = local_zone_unset,
550 	/** don't answer */
551 	respip_deny = local_zone_deny,
552 	/** redirect as per provided data */
553 	respip_redirect = local_zone_redirect,
554         /** log query source and answer query */
555 	respip_inform = local_zone_inform,
556         /** log query source and don't answer query */
557 	respip_inform_deny = local_zone_inform_deny,
558         /** log query source and redirect */
559 	respip_inform_redirect = local_zone_inform_redirect,
560         /** resolve normally, even when there is response-ip data */
561 	respip_always_transparent = local_zone_always_transparent,
562         /** answer with 'refused' response */
563 	respip_always_refuse = local_zone_always_refuse,
564         /** answer with 'no such domain' response */
565 	respip_always_nxdomain = local_zone_always_nxdomain,
566         /** answer with nodata response */
567 	respip_always_nodata = local_zone_always_nodata,
568         /** answer with nodata response */
569 	respip_always_deny = local_zone_always_deny,
570 	/** RPZ: truncate answer in order to force switch to tcp */
571 	respip_truncate = local_zone_truncate,
572 
573 	/* The rest of the values are only possible as
574 	 * access-control-tag-action */
575 
576 	/** serves response data (if any), else, drops queries. */
577 	respip_refuse = local_zone_refuse,
578 	/** serves response data, else, nodata answer. */
579 	respip_static = local_zone_static,
580 	/** gives response data (if any), else nodata answer. */
581 	respip_transparent = local_zone_transparent,
582 	/** gives response data (if any), else nodata answer. */
583 	respip_typetransparent = local_zone_typetransparent,
584 	/** type invalid */
585 	respip_invalid = local_zone_invalid,
586 };
587 
588 /**
589  * Get local data from local zone and encode answer.
590  * @param z: local zone to use
591  * @param env: module env
592  * @param qinfo: qinfo
593  * @param edns: edns data, for message encoding
594  * @param repinfo: reply info, for message encoding
595  * @param buf: commpoint buffer
596  * @param temp: scratchpad region
597  * @param labs: number of labels in qname
598  * @param ldp: where to store local data
599  * @param lz_type: type of local zone
600  * @param tag: matching tag index
601  * @param tag_datas: alc specific tag data list
602  * @param tag_datas_size: size of tag_datas
603  * @param tagname: list of names of tags, for logging purpose
604  * @param num_tags: number of tags
605  * @return 1 on success
606  */
607 int
608 local_data_answer(struct local_zone* z, struct module_env* env,
609 	struct query_info* qinfo, struct edns_data* edns,
610 	struct comm_reply* repinfo, sldns_buffer* buf,
611 	struct regional* temp, int labs, struct local_data** ldp,
612 	enum localzone_type lz_type, int tag, struct config_strlist** tag_datas,
613 	size_t tag_datas_size, char** tagname, int num_tags);
614 
615 /**
616  * Add RR to local zone.
617  * @param z: local zone to add RR to
618  * @param nm: dname of RR
619  * @param nmlen: length of nm
620  * @param nmlabs: number of labels of nm
621  * @param rrtype: RR type
622  * @param rrclass: RR class
623  * @param ttl: TTL of RR to add
624  * @param rdata: RDATA of RR to add
625  * @param rdata_len: length of rdata
626  * @param rrstr: RR in string format, for logging
627  * @return: 1 on success
628  */
629 int
630 local_zone_enter_rr(struct local_zone* z, uint8_t* nm, size_t nmlen,
631 	int nmlabs, uint16_t rrtype, uint16_t rrclass, time_t ttl,
632 	uint8_t* rdata, size_t rdata_len, const char* rrstr);
633 
634 /**
635  * Find a data node by exact name for a local zone
636  * @param z: local_zone containing data tree
637  * @param nm: name of local-data element to find
638  * @param nmlen: length of nm
639  * @param nmlabs: labs of nm
640  * @return local_data on exact match, NULL otherwise.
641  */
642 struct local_data*
643 local_zone_find_data(struct local_zone* z, uint8_t* nm, size_t nmlen, int nmlabs);
644 #endif /* SERVICES_LOCALZONE_H */
645