xref: /freebsd/contrib/unbound/util/data/packed_rrset.h (revision 5686c6c38a3e1cc78804eaf5f880bda23dcf592f)
1 /*
2  * util/data/packed_rrset.h - data storage for a set of resource records.
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 LIMITED
25  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
26  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE
27  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
28  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
29  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
30  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
31  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
32  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
33  * POSSIBILITY OF SUCH DAMAGE.
34  */
35 
36 /**
37  * \file
38  *
39  * This file contains the data storage for RRsets.
40  */
41 
42 #ifndef UTIL_DATA_PACKED_RRSET_H
43 #define UTIL_DATA_PACKED_RRSET_H
44 #include "util/storage/lruhash.h"
45 #include <ldns/rr.h>
46 struct alloc_cache;
47 struct regional;
48 
49 /** type used to uniquely identify rrsets. Cannot be reused without
50  * clearing the cache. */
51 typedef uint64_t rrset_id_t;
52 
53 /** this rrset is NSEC and is at zone apex (at child side of zonecut) */
54 #define PACKED_RRSET_NSEC_AT_APEX 0x1
55 /** this rrset is A/AAAA and is in-zone-glue (from parent side of zonecut) */
56 #define PACKED_RRSET_PARENT_SIDE 0x2
57 /** this rrset is SOA and has the negative ttl (from nxdomain or nodata),
58  * this is set on SOA rrsets in the authority section, to keep its TTL separate
59  * from the SOA in the answer section from a direct SOA query or ANY query. */
60 #define PACKED_RRSET_SOA_NEG 0x4
61 
62 /**
63  * The identifying information for an RRset.
64  */
65 struct packed_rrset_key {
66 	/**
67 	 * The domain name. If not null (for id=0) it is allocated, and
68 	 * contains the wireformat domain name.
69 	 * This dname is not canonicalized.
70 	 */
71 	uint8_t* dname;
72 	/**
73 	 * Length of the domain name, including last 0 root octet.
74 	 */
75 	size_t dname_len;
76 	/**
77 	 * Flags. 32bit to be easy for hashing:
78 	 * 	o PACKED_RRSET_NSEC_AT_APEX
79 	 * 	o PACKED_RRSET_PARENT_SIDE
80 	 * 	o PACKED_RRSET_SOA_NEG
81 	 */
82 	uint32_t flags;
83 	/** the rrset type in network format */
84 	uint16_t type;
85 	/** the rrset class in network format */
86 	uint16_t rrset_class;
87 };
88 
89 /**
90  * This structure contains an RRset. A set of resource records that
91  * share the same domain name, type and class.
92  *
93  * Due to memory management and threading, the key structure cannot be
94  * deleted, although the data can be. The id can be set to 0 to store and the
95  * structure can be recycled with a new id.
96  */
97 struct ub_packed_rrset_key {
98 	/**
99 	 * entry into hashtable. Note the lock is never destroyed,
100 	 *  even when this key is retired to the cache.
101 	 * the data pointer (if not null) points to a struct packed_rrset.
102 	 */
103 	struct lruhash_entry entry;
104 	/**
105 	 * the ID of this rrset. unique, based on threadid + sequenceno.
106 	 * ids are not reused, except after flushing the cache.
107 	 * zero is an unused entry, and never a valid id.
108 	 * Check this value after getting entry.lock.
109 	 * The other values in this struct may only be altered after changing
110 	 * the id (which needs a writelock on entry.lock).
111 	 */
112 	rrset_id_t id;
113 	/** key data: dname, type and class */
114 	struct packed_rrset_key rk;
115 };
116 
117 /**
118  * RRset trustworthiness. Bigger value is more trust. RFC 2181.
119  * The rrset_trust_add_noAA, rrset_trust_auth_noAA, rrset_trust_add_AA,
120  * are mentioned as the same trustworthiness in 2181, but split up here
121  * for ease of processing.
122  *
123  * rrset_trust_nonauth_ans_AA, rrset_trust_ans_noAA
124  * are also mentioned as the same trustworthiness in 2181, but split up here
125  * for ease of processing.
126  *
127  * Added trust_none for a sane initial value, smaller than anything else.
128  * Added validated and ultimate trust for keys and rrsig validated content.
129  */
130 enum rrset_trust {
131 	/** initial value for trust */
132 	rrset_trust_none = 0,
133 	/** Additional information from non-authoritative answers */
134 	rrset_trust_add_noAA,
135 	/** Data from the authority section of a non-authoritative answer */
136 	rrset_trust_auth_noAA,
137 	/** Additional information from an authoritative answer */
138 	rrset_trust_add_AA,
139 	/** non-authoritative data from the answer section of authoritative
140 	 * answers */
141 	rrset_trust_nonauth_ans_AA,
142 	/** Data from the answer section of a non-authoritative answer */
143 	rrset_trust_ans_noAA,
144 	/** Glue from a primary zone, or glue from a zone transfer */
145 	rrset_trust_glue,
146 	/** Data from the authority section of an authoritative answer */
147 	rrset_trust_auth_AA,
148 	/** The authoritative data included in the answer section of an
149 	 *  authoritative reply */
150 	rrset_trust_ans_AA,
151 	/** Data from a zone transfer, other than glue */
152 	rrset_trust_sec_noglue,
153 	/** Data from a primary zone file, other than glue data */
154 	rrset_trust_prim_noglue,
155 	/** DNSSEC(rfc4034) validated with trusted keys */
156 	rrset_trust_validated,
157 	/** ultimately trusted, no more trust is possible;
158 	 * trusted keys from the unbound configuration setup. */
159 	rrset_trust_ultimate
160 };
161 
162 /**
163  * Security status from validation for data.
164  * The order is significant; more secure, more proven later.
165  */
166 enum sec_status {
167 	/** UNCHECKED means that object has yet to be validated. */
168 	sec_status_unchecked = 0,
169 	/** BOGUS means that the object (RRset or message) failed to validate
170 	 *  (according to local policy), but should have validated. */
171 	sec_status_bogus,
172 	/** INDETERMINATE means that the object is insecure, but not
173 	 * authoritatively so. Generally this means that the RRset is not
174 	 * below a configured trust anchor. */
175 	sec_status_indeterminate,
176 	/** INSECURE means that the object is authoritatively known to be
177 	 * insecure. Generally this means that this RRset is below a trust
178 	 * anchor, but also below a verified, insecure delegation. */
179 	sec_status_insecure,
180 	/** SECURE means that the object (RRset or message) validated
181 	 * according to local policy. */
182 	sec_status_secure
183 };
184 
185 /**
186  * RRset data.
187  *
188  * The data is packed, stored contiguously in memory.
189  * memory layout:
190  *	o base struct
191  *	o rr_len size_t array
192  *	o rr_data uint8_t* array
193  *	o rr_ttl uint32_t array (after size_t and ptrs because those may be
194  *		64bit and this array before those would make them unaligned).
195  *		Since the stuff before is 32/64bit, rr_ttl is 32 bit aligned.
196  *	o rr_data rdata wireformats
197  *	o rrsig_data rdata wireformat(s)
198  *
199  * Rdata is stored in wireformat. The dname is stored in wireformat.
200  * TTLs are stored as absolute values (and could be expired).
201  *
202  * RRSIGs are stored in the arrays after the regular rrs.
203  *
204  * You need the packed_rrset_key to know dname, type, class of the
205  * resource records in this RRset. (if signed the rrsig gives the type too).
206  *
207  * On the wire an RR is:
208  *	name, type, class, ttl, rdlength, rdata.
209  * So we need to send the following per RR:
210  *	key.dname, ttl, rr_data[i].
211  *	since key.dname ends with type and class.
212  *	and rr_data starts with the rdlength.
213  *	the ttl value to send changes due to time.
214  */
215 struct packed_rrset_data {
216 	/** TTL (in seconds like time()) of the rrset.
217 	 * Same for all RRs see rfc2181(5.2).  */
218 	uint32_t ttl;
219 	/** number of rrs. */
220 	size_t count;
221 	/** number of rrsigs, if 0 no rrsigs */
222 	size_t rrsig_count;
223 	/** the trustworthiness of the rrset data */
224 	enum rrset_trust trust;
225 	/** security status of the rrset data */
226 	enum sec_status security;
227 	/** length of every rr's rdata, rr_len[i] is size of rr_data[i]. */
228 	size_t* rr_len;
229 	/** ttl of every rr. rr_ttl[i] ttl of rr i. */
230 	uint32_t *rr_ttl;
231 	/**
232 	 * Array of pointers to every rr's rdata.
233 	 * The rr_data[i] rdata is stored in uncompressed wireformat.
234 	 * The first uint16_t of rr_data[i] is network format rdlength.
235 	 *
236 	 * rr_data[count] to rr_data[count+rrsig_count] contain the rrsig data.
237 	 */
238 	uint8_t** rr_data;
239 };
240 
241 /**
242  * An RRset can be represented using both key and data together.
243  * Split into key and data structures to simplify implementation of
244  * caching schemes.
245  */
246 struct packed_rrset {
247 	/** domain name, type and class */
248 	struct packed_rrset_key* k;
249 	/** ttl, count and rdatas (and rrsig) */
250 	struct packed_rrset_data* d;
251 };
252 
253 /**
254  * list of packed rrsets
255  */
256 struct packed_rrset_list {
257 	/** next in list */
258 	struct packed_rrset_list* next;
259 	/** rrset key and data */
260 	struct packed_rrset rrset;
261 };
262 
263 /**
264  * Delete packed rrset key and data, not entered in hashtables yet.
265  * Used during parsing.
266  * @param pkey: rrset key structure with locks, key and data pointers.
267  * @param alloc: where to return the unfree-able key structure.
268  */
269 void ub_packed_rrset_parsedelete(struct ub_packed_rrset_key* pkey,
270 	struct alloc_cache* alloc);
271 
272 /**
273  * Memory size of rrset data. RRset data must be filled in correctly.
274  * @param data: data to examine.
275  * @return size in bytes.
276  */
277 size_t packed_rrset_sizeof(struct packed_rrset_data* data);
278 
279 /**
280  * Get TTL of rrset. RRset data must be filled in correctly.
281  * @param key: rrset key, with data to examine.
282  * @return ttl value.
283  */
284 uint32_t ub_packed_rrset_ttl(struct ub_packed_rrset_key* key);
285 
286 /**
287  * Calculate memory size of rrset entry. For hash table usage.
288  * @param key: struct ub_packed_rrset_key*.
289  * @param data: struct packed_rrset_data*.
290  * @return size in bytes.
291  */
292 size_t ub_rrset_sizefunc(void* key, void* data);
293 
294 /**
295  * compares two rrset keys.
296  * @param k1: struct ub_packed_rrset_key*.
297  * @param k2: struct ub_packed_rrset_key*.
298  * @return 0 if equal.
299  */
300 int ub_rrset_compare(void* k1, void* k2);
301 
302 /**
303  * compare two rrset data structures.
304  * Compared rdata and rrsigdata, not the trust or ttl value.
305  * @param d1: data to compare.
306  * @param d2: data to compare.
307  * @return 1 if equal.
308  */
309 int rrsetdata_equal(struct packed_rrset_data* d1, struct packed_rrset_data* d2);
310 
311 /**
312  * Old key to be deleted. RRset keys are recycled via alloc.
313  * The id is set to 0. So that other threads, after acquiring a lock always
314  * get the correct value, in this case the 0 deleted-special value.
315  * @param key: struct ub_packed_rrset_key*.
316  * @param userdata: alloc structure to use for recycling.
317  */
318 void ub_rrset_key_delete(void* key, void* userdata);
319 
320 /**
321  * Old data to be deleted.
322  * @param data: what to delete.
323  * @param userdata: user data ptr.
324  */
325 void rrset_data_delete(void* data, void* userdata);
326 
327 /**
328  * Calculate hash value for a packed rrset key.
329  * @param key: the rrset key with name, type, class, flags.
330  * @return hash value.
331  */
332 hashvalue_t rrset_key_hash(struct packed_rrset_key* key);
333 
334 /**
335  * Fixup pointers in fixed data packed_rrset_data blob.
336  * After a memcpy of the data for example. Will set internal pointers right.
337  * @param data: rrset data structure. Otherwise correctly filled in.
338  */
339 void packed_rrset_ptr_fixup(struct packed_rrset_data* data);
340 
341 /**
342  * Fixup TTLs in fixed data packed_rrset_data blob.
343  * @param data: rrset data structure. Otherwise correctly filled in.
344  * @param add: how many seconds to add, pass time(0) for example.
345  */
346 void packed_rrset_ttl_add(struct packed_rrset_data* data, uint32_t add);
347 
348 /**
349  * Utility procedure to extract CNAME target name from its rdata.
350  * Failsafes; it will change passed dname to a valid dname or do nothing.
351  * @param rrset: the rrset structure. Must be a CNAME.
352  *	Only first RR is used (multiple RRs are technically illegal anyway).
353  * 	Also works on type DNAME. Returns target name.
354  * @param dname: this pointer is updated to point into the cname rdata.
355  *	If a failsafe fails, nothing happens to the pointer (such as the
356  *	rdata was not a valid dname, not a CNAME, ...).
357  * @param dname_len: length of dname is returned.
358  */
359 void get_cname_target(struct ub_packed_rrset_key* rrset, uint8_t** dname,
360 	size_t* dname_len);
361 
362 /**
363  * Get a printable string for a rrset trust value
364  * @param s: rrset trust value
365  * @return printable string.
366  */
367 const char* rrset_trust_to_string(enum rrset_trust s);
368 
369 /**
370  * Get a printable string for a security status value
371  * @param s: security status
372  * @return printable string.
373  */
374 const char* sec_status_to_string(enum sec_status s);
375 
376 /**
377  * Print string with neat domain name, type, class from rrset.
378  * @param v: at what verbosity level to print this.
379  * @param str: string of message.
380  * @param rrset: structure with name, type and class.
381  */
382 void log_rrset_key(enum verbosity_value v, const char* str,
383 	struct ub_packed_rrset_key* rrset);
384 
385 /**
386  * Allocate rrset in region - no more locks needed
387  * @param key: a (just from rrset cache looked up) rrset key + valid,
388  * 	packed data record.
389  * @param region: where to alloc the copy
390  * @param now: adjust the TTLs to be relative (subtract from all TTLs).
391  * @return new region-alloced rrset key or NULL on alloc failure.
392  */
393 struct ub_packed_rrset_key* packed_rrset_copy_region(
394 	struct ub_packed_rrset_key* key, struct regional* region,
395 	uint32_t now);
396 
397 /**
398  * Allocate rrset with malloc (from region or you are holding the lock).
399  * @param key: key with data entry.
400  * @param alloc: alloc_cache to create rrset_keys
401  * @param now: adjust the TTLs to be absolute (add to all TTLs).
402  * @return new region-alloced rrset key or NULL on alloc failure.
403  */
404 struct ub_packed_rrset_key* packed_rrset_copy_alloc(
405 	struct ub_packed_rrset_key* key, struct alloc_cache* alloc,
406 	uint32_t now);
407 
408 /**
409  * Create a ub_packed_rrset_key allocated on the heap.
410  * It therefore does not have the correct ID value, and cannot be used
411  * inside the cache.  It can be used in storage outside of the cache.
412  * Keys for the cache have to be obtained from alloc.h .
413  * @param rrset: the ldns rr set.
414  * @return key allocated or NULL on failure.
415  */
416 struct ub_packed_rrset_key* ub_packed_rrset_heap_key(ldns_rr_list* rrset);
417 
418 /**
419  * Create packed_rrset data on the heap.
420  * @param rrset: the ldns rr set with the data to copy.
421  * @return data allocated or NULL on failure.
422  */
423 struct packed_rrset_data* packed_rrset_heap_data(ldns_rr_list* rrset);
424 
425 /**
426  * Convert packed rrset to ldns rr list.
427  * @param rrset: packed rrset.
428  * @param buf: scratch buffer.
429  * @return rr list or NULL on failure.
430  */
431 ldns_rr_list* packed_rrset_to_rr_list(struct ub_packed_rrset_key* rrset,
432 	ldns_buffer* buf);
433 
434 #endif /* UTIL_DATA_PACKED_RRSET_H */
435