xref: /freebsd/contrib/unbound/util/data/packed_rrset.h (revision f4b37ed0f8b307b1f3f0f630ca725d68f1dff30d)
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
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 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 struct alloc_cache;
46 struct regional;
47 
48 /** type used to uniquely identify rrsets. Cannot be reused without
49  * clearing the cache. */
50 typedef uint64_t rrset_id_t;
51 
52 /** this rrset is NSEC and is at zone apex (at child side of zonecut) */
53 #define PACKED_RRSET_NSEC_AT_APEX 0x1
54 /** this rrset is A/AAAA and is in-zone-glue (from parent side of zonecut) */
55 #define PACKED_RRSET_PARENT_SIDE 0x2
56 /** this rrset is SOA and has the negative ttl (from nxdomain or nodata),
57  * this is set on SOA rrsets in the authority section, to keep its TTL separate
58  * from the SOA in the answer section from a direct SOA query or ANY query. */
59 #define PACKED_RRSET_SOA_NEG 0x4
60 
61 /**
62  * The identifying information for an RRset.
63  */
64 struct packed_rrset_key {
65 	/**
66 	 * The domain name. If not null (for id=0) it is allocated, and
67 	 * contains the wireformat domain name.
68 	 * This dname is not canonicalized.
69 	 */
70 	uint8_t* dname;
71 	/**
72 	 * Length of the domain name, including last 0 root octet.
73 	 */
74 	size_t dname_len;
75 	/**
76 	 * Flags. 32bit to be easy for hashing:
77 	 * 	o PACKED_RRSET_NSEC_AT_APEX
78 	 * 	o PACKED_RRSET_PARENT_SIDE
79 	 * 	o PACKED_RRSET_SOA_NEG
80 	 */
81 	uint32_t flags;
82 	/** the rrset type in network format */
83 	uint16_t type;
84 	/** the rrset class in network format */
85 	uint16_t rrset_class;
86 };
87 
88 /**
89  * This structure contains an RRset. A set of resource records that
90  * share the same domain name, type and class.
91  *
92  * Due to memory management and threading, the key structure cannot be
93  * deleted, although the data can be. The id can be set to 0 to store and the
94  * structure can be recycled with a new id.
95  */
96 struct ub_packed_rrset_key {
97 	/**
98 	 * entry into hashtable. Note the lock is never destroyed,
99 	 *  even when this key is retired to the cache.
100 	 * the data pointer (if not null) points to a struct packed_rrset.
101 	 */
102 	struct lruhash_entry entry;
103 	/**
104 	 * the ID of this rrset. unique, based on threadid + sequenceno.
105 	 * ids are not reused, except after flushing the cache.
106 	 * zero is an unused entry, and never a valid id.
107 	 * Check this value after getting entry.lock.
108 	 * The other values in this struct may only be altered after changing
109 	 * the id (which needs a writelock on entry.lock).
110 	 */
111 	rrset_id_t id;
112 	/** key data: dname, type and class */
113 	struct packed_rrset_key rk;
114 };
115 
116 /**
117  * RRset trustworthiness. Bigger value is more trust. RFC 2181.
118  * The rrset_trust_add_noAA, rrset_trust_auth_noAA, rrset_trust_add_AA,
119  * are mentioned as the same trustworthiness in 2181, but split up here
120  * for ease of processing.
121  *
122  * rrset_trust_nonauth_ans_AA, rrset_trust_ans_noAA
123  * are also mentioned as the same trustworthiness in 2181, but split up here
124  * for ease of processing.
125  *
126  * Added trust_none for a sane initial value, smaller than anything else.
127  * Added validated and ultimate trust for keys and rrsig validated content.
128  */
129 enum rrset_trust {
130 	/** initial value for trust */
131 	rrset_trust_none = 0,
132 	/** Additional information from non-authoritative answers */
133 	rrset_trust_add_noAA,
134 	/** Data from the authority section of a non-authoritative answer */
135 	rrset_trust_auth_noAA,
136 	/** Additional information from an authoritative answer */
137 	rrset_trust_add_AA,
138 	/** non-authoritative data from the answer section of authoritative
139 	 * answers */
140 	rrset_trust_nonauth_ans_AA,
141 	/** Data from the answer section of a non-authoritative answer */
142 	rrset_trust_ans_noAA,
143 	/** Glue from a primary zone, or glue from a zone transfer */
144 	rrset_trust_glue,
145 	/** Data from the authority section of an authoritative answer */
146 	rrset_trust_auth_AA,
147 	/** The authoritative data included in the answer section of an
148 	 *  authoritative reply */
149 	rrset_trust_ans_AA,
150 	/** Data from a zone transfer, other than glue */
151 	rrset_trust_sec_noglue,
152 	/** Data from a primary zone file, other than glue data */
153 	rrset_trust_prim_noglue,
154 	/** DNSSEC(rfc4034) validated with trusted keys */
155 	rrset_trust_validated,
156 	/** ultimately trusted, no more trust is possible;
157 	 * trusted keys from the unbound configuration setup. */
158 	rrset_trust_ultimate
159 };
160 
161 /**
162  * Security status from validation for data.
163  * The order is significant; more secure, more proven later.
164  */
165 enum sec_status {
166 	/** UNCHECKED means that object has yet to be validated. */
167 	sec_status_unchecked = 0,
168 	/** BOGUS means that the object (RRset or message) failed to validate
169 	 *  (according to local policy), but should have validated. */
170 	sec_status_bogus,
171 	/** INDETERMINATE means that the object is insecure, but not
172 	 * authoritatively so. Generally this means that the RRset is not
173 	 * below a configured trust anchor. */
174 	sec_status_indeterminate,
175 	/** INSECURE means that the object is authoritatively known to be
176 	 * insecure. Generally this means that this RRset is below a trust
177 	 * anchor, but also below a verified, insecure delegation. */
178 	sec_status_insecure,
179 	/** SECURE means that the object (RRset or message) validated
180 	 * according to local policy. */
181 	sec_status_secure
182 };
183 
184 /**
185  * RRset data.
186  *
187  * The data is packed, stored contiguously in memory.
188  * memory layout:
189  *	o base struct
190  *	o rr_len size_t array
191  *	o rr_data uint8_t* array
192  *	o rr_ttl time_t array (after size_t and ptrs because those may be
193  *		64bit and this array before those would make them unaligned).
194  *		Since the stuff before is 32/64bit, rr_ttl is 32 bit aligned.
195  *	o rr_data rdata wireformats
196  *	o rrsig_data rdata wireformat(s)
197  *
198  * Rdata is stored in wireformat. The dname is stored in wireformat.
199  * TTLs are stored as absolute values (and could be expired).
200  *
201  * RRSIGs are stored in the arrays after the regular rrs.
202  *
203  * You need the packed_rrset_key to know dname, type, class of the
204  * resource records in this RRset. (if signed the rrsig gives the type too).
205  *
206  * On the wire an RR is:
207  *	name, type, class, ttl, rdlength, rdata.
208  * So we need to send the following per RR:
209  *	key.dname, ttl, rr_data[i].
210  *	since key.dname ends with type and class.
211  *	and rr_data starts with the rdlength.
212  *	the ttl value to send changes due to time.
213  */
214 struct packed_rrset_data {
215 	/** TTL (in seconds like time()) of the rrset.
216 	 * Same for all RRs see rfc2181(5.2).  */
217 	time_t ttl;
218 	/** number of rrs. */
219 	size_t count;
220 	/** number of rrsigs, if 0 no rrsigs */
221 	size_t rrsig_count;
222 	/** the trustworthiness of the rrset data */
223 	enum rrset_trust trust;
224 	/** security status of the rrset data */
225 	enum sec_status security;
226 	/** length of every rr's rdata, rr_len[i] is size of rr_data[i]. */
227 	size_t* rr_len;
228 	/** ttl of every rr. rr_ttl[i] ttl of rr i. */
229 	time_t *rr_ttl;
230 	/**
231 	 * Array of pointers to every rr's rdata.
232 	 * The rr_data[i] rdata is stored in uncompressed wireformat.
233 	 * The first uint16_t of rr_data[i] is network format rdlength.
234 	 *
235 	 * rr_data[count] to rr_data[count+rrsig_count] contain the rrsig data.
236 	 */
237 	uint8_t** rr_data;
238 };
239 
240 /**
241  * An RRset can be represented using both key and data together.
242  * Split into key and data structures to simplify implementation of
243  * caching schemes.
244  */
245 struct packed_rrset {
246 	/** domain name, type and class */
247 	struct packed_rrset_key* k;
248 	/** ttl, count and rdatas (and rrsig) */
249 	struct packed_rrset_data* d;
250 };
251 
252 /**
253  * list of packed rrsets
254  */
255 struct packed_rrset_list {
256 	/** next in list */
257 	struct packed_rrset_list* next;
258 	/** rrset key and data */
259 	struct packed_rrset rrset;
260 };
261 
262 /**
263  * Delete packed rrset key and data, not entered in hashtables yet.
264  * Used during parsing.
265  * @param pkey: rrset key structure with locks, key and data pointers.
266  * @param alloc: where to return the unfree-able key structure.
267  */
268 void ub_packed_rrset_parsedelete(struct ub_packed_rrset_key* pkey,
269 	struct alloc_cache* alloc);
270 
271 /**
272  * Memory size of rrset data. RRset data must be filled in correctly.
273  * @param data: data to examine.
274  * @return size in bytes.
275  */
276 size_t packed_rrset_sizeof(struct packed_rrset_data* data);
277 
278 /**
279  * Get TTL of rrset. RRset data must be filled in correctly.
280  * @param key: rrset key, with data to examine.
281  * @return ttl value.
282  */
283 time_t ub_packed_rrset_ttl(struct ub_packed_rrset_key* key);
284 
285 /**
286  * Calculate memory size of rrset entry. For hash table usage.
287  * @param key: struct ub_packed_rrset_key*.
288  * @param data: struct packed_rrset_data*.
289  * @return size in bytes.
290  */
291 size_t ub_rrset_sizefunc(void* key, void* data);
292 
293 /**
294  * compares two rrset keys.
295  * @param k1: struct ub_packed_rrset_key*.
296  * @param k2: struct ub_packed_rrset_key*.
297  * @return 0 if equal.
298  */
299 int ub_rrset_compare(void* k1, void* k2);
300 
301 /**
302  * compare two rrset data structures.
303  * Compared rdata and rrsigdata, not the trust or ttl value.
304  * @param d1: data to compare.
305  * @param d2: data to compare.
306  * @return 1 if equal.
307  */
308 int rrsetdata_equal(struct packed_rrset_data* d1, struct packed_rrset_data* d2);
309 
310 /**
311  * Old key to be deleted. RRset keys are recycled via alloc.
312  * The id is set to 0. So that other threads, after acquiring a lock always
313  * get the correct value, in this case the 0 deleted-special value.
314  * @param key: struct ub_packed_rrset_key*.
315  * @param userdata: alloc structure to use for recycling.
316  */
317 void ub_rrset_key_delete(void* key, void* userdata);
318 
319 /**
320  * Old data to be deleted.
321  * @param data: what to delete.
322  * @param userdata: user data ptr.
323  */
324 void rrset_data_delete(void* data, void* userdata);
325 
326 /**
327  * Calculate hash value for a packed rrset key.
328  * @param key: the rrset key with name, type, class, flags.
329  * @return hash value.
330  */
331 hashvalue_t rrset_key_hash(struct packed_rrset_key* key);
332 
333 /**
334  * Fixup pointers in fixed data packed_rrset_data blob.
335  * After a memcpy of the data for example. Will set internal pointers right.
336  * @param data: rrset data structure. Otherwise correctly filled in.
337  */
338 void packed_rrset_ptr_fixup(struct packed_rrset_data* data);
339 
340 /**
341  * Fixup TTLs in fixed data packed_rrset_data blob.
342  * @param data: rrset data structure. Otherwise correctly filled in.
343  * @param add: how many seconds to add, pass time(0) for example.
344  */
345 void packed_rrset_ttl_add(struct packed_rrset_data* data, time_t add);
346 
347 /**
348  * Utility procedure to extract CNAME target name from its rdata.
349  * Failsafes; it will change passed dname to a valid dname or do nothing.
350  * @param rrset: the rrset structure. Must be a CNAME.
351  *	Only first RR is used (multiple RRs are technically illegal anyway).
352  * 	Also works on type DNAME. Returns target name.
353  * @param dname: this pointer is updated to point into the cname rdata.
354  *	If a failsafe fails, nothing happens to the pointer (such as the
355  *	rdata was not a valid dname, not a CNAME, ...).
356  * @param dname_len: length of dname is returned.
357  */
358 void get_cname_target(struct ub_packed_rrset_key* rrset, uint8_t** dname,
359 	size_t* dname_len);
360 
361 /**
362  * Get a printable string for a rrset trust value
363  * @param s: rrset trust value
364  * @return printable string.
365  */
366 const char* rrset_trust_to_string(enum rrset_trust s);
367 
368 /**
369  * Get a printable string for a security status value
370  * @param s: security status
371  * @return printable string.
372  */
373 const char* sec_status_to_string(enum sec_status s);
374 
375 /**
376  * Print string with neat domain name, type, class from rrset.
377  * @param v: at what verbosity level to print this.
378  * @param str: string of message.
379  * @param rrset: structure with name, type and class.
380  */
381 void log_rrset_key(enum verbosity_value v, const char* str,
382 	struct ub_packed_rrset_key* rrset);
383 
384 /**
385  * Convert RR from RRset to string.
386  * @param rrset: structure with data.
387  * @param i: index of rr or RRSIG.
388  * @param now: time that is subtracted from ttl before printout. Can be 0.
389  * @param dest: destination string buffer. Must be nonNULL.
390  * @param dest_len: length of dest buffer (>0).
391  * @return false on failure.
392  */
393 int packed_rr_to_string(struct ub_packed_rrset_key* rrset, size_t i,
394 	time_t now, char* dest, size_t dest_len);
395 
396 /**
397  * Print the string with prefix, one rr per line.
398  * @param v: at what verbosity level to print this.
399  * @param str: string of message.
400  * @param rrset: with name, and rdata, and rrsigs.
401  */
402 void log_packed_rrset(enum verbosity_value v, const char* str,
403 	struct ub_packed_rrset_key* rrset);
404 
405 /**
406  * Allocate rrset in region - no more locks needed
407  * @param key: a (just from rrset cache looked up) rrset key + valid,
408  * 	packed data record.
409  * @param region: where to alloc the copy
410  * @param now: adjust the TTLs to be relative (subtract from all TTLs).
411  * @return new region-alloced rrset key or NULL on alloc failure.
412  */
413 struct ub_packed_rrset_key* packed_rrset_copy_region(
414 	struct ub_packed_rrset_key* key, struct regional* region,
415 	time_t now);
416 
417 /**
418  * Allocate rrset with malloc (from region or you are holding the lock).
419  * @param key: key with data entry.
420  * @param alloc: alloc_cache to create rrset_keys
421  * @param now: adjust the TTLs to be absolute (add to all TTLs).
422  * @return new region-alloced rrset key or NULL on alloc failure.
423  */
424 struct ub_packed_rrset_key* packed_rrset_copy_alloc(
425 	struct ub_packed_rrset_key* key, struct alloc_cache* alloc,
426 	time_t now);
427 
428 #endif /* UTIL_DATA_PACKED_RRSET_H */
429