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