xref: /freebsd/contrib/unbound/util/data/packed_rrset.h (revision 6829dae12bb055451fa467da4589c43bd03b1e64)
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_type;
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 /** This rrset is considered to have a fixed TTL; its TTL doesn't have to be
61  * updated on encoding in a reply.  This flag is not expected to be set in
62  * cached data. */
63 #define PACKED_RRSET_FIXEDTTL 0x80000000
64 
65 /** number of rrs and rrsets for integer overflow protection.  More than
66  * this is not really possible (64K packet has much less RRs and RRsets) in
67  * a message.  And this is small enough that also multiplied there is no
68  * integer overflow. */
69 #define RR_COUNT_MAX 0xffffff
70 
71 /**
72  * The identifying information for an RRset.
73  */
74 struct packed_rrset_key {
75 	/**
76 	 * The domain name. If not null (for id=0) it is allocated, and
77 	 * contains the wireformat domain name.
78 	 * This dname is not canonicalized.
79 	 */
80 	uint8_t* dname;
81 	/**
82 	 * Length of the domain name, including last 0 root octet.
83 	 */
84 	size_t dname_len;
85 	/**
86 	 * Flags. 32bit to be easy for hashing:
87 	 * 	o PACKED_RRSET_NSEC_AT_APEX
88 	 * 	o PACKED_RRSET_PARENT_SIDE
89 	 * 	o PACKED_RRSET_SOA_NEG
90 	 * 	o PACKED_RRSET_FIXEDTTL (not supposed to be cached)
91 	 */
92 	uint32_t flags;
93 	/** the rrset type in network format */
94 	uint16_t type;
95 	/** the rrset class in network format */
96 	uint16_t rrset_class;
97 };
98 
99 /**
100  * This structure contains an RRset. A set of resource records that
101  * share the same domain name, type and class.
102  *
103  * Due to memory management and threading, the key structure cannot be
104  * deleted, although the data can be. The id can be set to 0 to store and the
105  * structure can be recycled with a new id.
106  */
107 struct ub_packed_rrset_key {
108 	/**
109 	 * entry into hashtable. Note the lock is never destroyed,
110 	 *  even when this key is retired to the cache.
111 	 * the data pointer (if not null) points to a struct packed_rrset.
112 	 */
113 	struct lruhash_entry entry;
114 	/**
115 	 * the ID of this rrset. unique, based on threadid + sequenceno.
116 	 * ids are not reused, except after flushing the cache.
117 	 * zero is an unused entry, and never a valid id.
118 	 * Check this value after getting entry.lock.
119 	 * The other values in this struct may only be altered after changing
120 	 * the id (which needs a writelock on entry.lock).
121 	 */
122 	rrset_id_type id;
123 	/** key data: dname, type and class */
124 	struct packed_rrset_key rk;
125 };
126 
127 /**
128  * RRset trustworthiness. Bigger value is more trust. RFC 2181.
129  * The rrset_trust_add_noAA, rrset_trust_auth_noAA, rrset_trust_add_AA,
130  * are mentioned as the same trustworthiness in 2181, but split up here
131  * for ease of processing.
132  *
133  * rrset_trust_nonauth_ans_AA, rrset_trust_ans_noAA
134  * are also mentioned as the same trustworthiness in 2181, but split up here
135  * for ease of processing.
136  *
137  * Added trust_none for a sane initial value, smaller than anything else.
138  * Added validated and ultimate trust for keys and rrsig validated content.
139  */
140 enum rrset_trust {
141 	/** initial value for trust */
142 	rrset_trust_none = 0,
143 	/** Additional information from non-authoritative answers */
144 	rrset_trust_add_noAA,
145 	/** Data from the authority section of a non-authoritative answer */
146 	rrset_trust_auth_noAA,
147 	/** Additional information from an authoritative answer */
148 	rrset_trust_add_AA,
149 	/** non-authoritative data from the answer section of authoritative
150 	 * answers */
151 	rrset_trust_nonauth_ans_AA,
152 	/** Data from the answer section of a non-authoritative answer */
153 	rrset_trust_ans_noAA,
154 	/** Glue from a primary zone, or glue from a zone transfer */
155 	rrset_trust_glue,
156 	/** Data from the authority section of an authoritative answer */
157 	rrset_trust_auth_AA,
158 	/** The authoritative data included in the answer section of an
159 	 *  authoritative reply */
160 	rrset_trust_ans_AA,
161 	/** Data from a zone transfer, other than glue */
162 	rrset_trust_sec_noglue,
163 	/** Data from a primary zone file, other than glue data */
164 	rrset_trust_prim_noglue,
165 	/** DNSSEC(rfc4034) validated with trusted keys */
166 	rrset_trust_validated,
167 	/** ultimately trusted, no more trust is possible;
168 	 * trusted keys from the unbound configuration setup. */
169 	rrset_trust_ultimate
170 };
171 
172 /**
173  * Security status from validation for data.
174  * The order is significant; more secure, more proven later.
175  */
176 enum sec_status {
177 	/** UNCHECKED means that object has yet to be validated. */
178 	sec_status_unchecked = 0,
179 	/** BOGUS means that the object (RRset or message) failed to validate
180 	 *  (according to local policy), but should have validated. */
181 	sec_status_bogus,
182 	/** INDETERMINATE means that the object is insecure, but not
183 	 * authoritatively so. Generally this means that the RRset is not
184 	 * below a configured trust anchor. */
185 	sec_status_indeterminate,
186 	/** INSECURE means that the object is authoritatively known to be
187 	 * insecure. Generally this means that this RRset is below a trust
188 	 * anchor, but also below a verified, insecure delegation. */
189 	sec_status_insecure,
190 	/** SECURE_SENTINEL_FAIL means that the object (RRset or message)
191 	 * validated according to local policy but did not succeed in the root
192 	 * KSK sentinel test (draft-ietf-dnsop-kskroll-sentinel). */
193 	sec_status_secure_sentinel_fail,
194 	/** SECURE means that the object (RRset or message) validated
195 	 * according to local policy. */
196 	sec_status_secure
197 };
198 
199 /**
200  * RRset data.
201  *
202  * The data is packed, stored contiguously in memory.
203  *
204  * It is not always stored contiguously, in that case, an unpacked-packed
205  * rrset has the arrays separate.  A bunch of routines work on that, but
206  * the packed rrset that is contiguous is for the rrset-cache and the
207  * cache-response routines in daemon/worker.c.
208  *
209  * memory layout:
210  *	o base struct
211  *	o rr_len size_t array
212  *	o rr_data uint8_t* array
213  *	o rr_ttl time_t array (after size_t and ptrs because those may be
214  *		64bit and this array before those would make them unaligned).
215  *		Since the stuff before is 32/64bit, rr_ttl is 32 bit aligned.
216  *	o rr_data rdata wireformats
217  *	o rrsig_data rdata wireformat(s)
218  *
219  * Rdata is stored in wireformat. The dname is stored in wireformat.
220  * TTLs are stored as absolute values (and could be expired).
221  *
222  * RRSIGs are stored in the arrays after the regular rrs.
223  *
224  * You need the packed_rrset_key to know dname, type, class of the
225  * resource records in this RRset. (if signed the rrsig gives the type too).
226  *
227  * On the wire an RR is:
228  *	name, type, class, ttl, rdlength, rdata.
229  * So we need to send the following per RR:
230  *	key.dname, ttl, rr_data[i].
231  *	since key.dname ends with type and class.
232  *	and rr_data starts with the rdlength.
233  *	the ttl value to send changes due to time.
234  */
235 struct packed_rrset_data {
236 	/** TTL (in seconds like time()) of the rrset.
237 	 * Same for all RRs see rfc2181(5.2).  */
238 	time_t ttl;
239 	/** number of rrs. */
240 	size_t count;
241 	/** number of rrsigs, if 0 no rrsigs */
242 	size_t rrsig_count;
243 	/** the trustworthiness of the rrset data */
244 	enum rrset_trust trust;
245 	/** security status of the rrset data */
246 	enum sec_status security;
247 	/** length of every rr's rdata, rr_len[i] is size of rr_data[i]. */
248 	size_t* rr_len;
249 	/** ttl of every rr. rr_ttl[i] ttl of rr i. */
250 	time_t *rr_ttl;
251 	/**
252 	 * Array of pointers to every rr's rdata.
253 	 * The rr_data[i] rdata is stored in uncompressed wireformat.
254 	 * The first uint16_t of rr_data[i] is network format rdlength.
255 	 *
256 	 * rr_data[count] to rr_data[count+rrsig_count] contain the rrsig data.
257 	 */
258 	uint8_t** rr_data;
259 };
260 
261 /**
262  * An RRset can be represented using both key and data together.
263  * Split into key and data structures to simplify implementation of
264  * caching schemes.
265  */
266 struct packed_rrset {
267 	/** domain name, type and class */
268 	struct packed_rrset_key* k;
269 	/** ttl, count and rdatas (and rrsig) */
270 	struct packed_rrset_data* d;
271 };
272 
273 /**
274  * list of packed rrsets
275  */
276 struct packed_rrset_list {
277 	/** next in list */
278 	struct packed_rrset_list* next;
279 	/** rrset key and data */
280 	struct packed_rrset rrset;
281 };
282 
283 /**
284  * Delete packed rrset key and data, not entered in hashtables yet.
285  * Used during parsing.
286  * @param pkey: rrset key structure with locks, key and data pointers.
287  * @param alloc: where to return the unfree-able key structure.
288  */
289 void ub_packed_rrset_parsedelete(struct ub_packed_rrset_key* pkey,
290 	struct alloc_cache* alloc);
291 
292 /**
293  * Memory size of rrset data. RRset data must be filled in correctly.
294  * @param data: data to examine.
295  * @return size in bytes.
296  */
297 size_t packed_rrset_sizeof(struct packed_rrset_data* data);
298 
299 /**
300  * Get TTL of rrset. RRset data must be filled in correctly.
301  * @param key: rrset key, with data to examine.
302  * @return ttl value.
303  */
304 time_t ub_packed_rrset_ttl(struct ub_packed_rrset_key* key);
305 
306 /**
307  * Calculate memory size of rrset entry. For hash table usage.
308  * @param key: struct ub_packed_rrset_key*.
309  * @param data: struct packed_rrset_data*.
310  * @return size in bytes.
311  */
312 size_t ub_rrset_sizefunc(void* key, void* data);
313 
314 /**
315  * compares two rrset keys.
316  * @param k1: struct ub_packed_rrset_key*.
317  * @param k2: struct ub_packed_rrset_key*.
318  * @return 0 if equal.
319  */
320 int ub_rrset_compare(void* k1, void* k2);
321 
322 /**
323  * compare two rrset data structures.
324  * Compared rdata and rrsigdata, not the trust or ttl value.
325  * @param d1: data to compare.
326  * @param d2: data to compare.
327  * @return 1 if equal.
328  */
329 int rrsetdata_equal(struct packed_rrset_data* d1, struct packed_rrset_data* d2);
330 
331 /**
332  * Old key to be deleted. RRset keys are recycled via alloc.
333  * The id is set to 0. So that other threads, after acquiring a lock always
334  * get the correct value, in this case the 0 deleted-special value.
335  * @param key: struct ub_packed_rrset_key*.
336  * @param userdata: alloc structure to use for recycling.
337  */
338 void ub_rrset_key_delete(void* key, void* userdata);
339 
340 /**
341  * Old data to be deleted.
342  * @param data: what to delete.
343  * @param userdata: user data ptr.
344  */
345 void rrset_data_delete(void* data, void* userdata);
346 
347 /**
348  * Calculate hash value for a packed rrset key.
349  * @param key: the rrset key with name, type, class, flags.
350  * @return hash value.
351  */
352 hashvalue_type rrset_key_hash(struct packed_rrset_key* key);
353 
354 /**
355  * Fixup pointers in fixed data packed_rrset_data blob.
356  * After a memcpy of the data for example. Will set internal pointers right.
357  * @param data: rrset data structure. Otherwise correctly filled in.
358  */
359 void packed_rrset_ptr_fixup(struct packed_rrset_data* data);
360 
361 /**
362  * Fixup TTLs in fixed data packed_rrset_data blob.
363  * @param data: rrset data structure. Otherwise correctly filled in.
364  * @param add: how many seconds to add, pass time(0) for example.
365  */
366 void packed_rrset_ttl_add(struct packed_rrset_data* data, time_t add);
367 
368 /**
369  * Utility procedure to extract CNAME target name from its rdata.
370  * Failsafes; it will change passed dname to a valid dname or do nothing.
371  * @param rrset: the rrset structure. Must be a CNAME.
372  *	Only first RR is used (multiple RRs are technically illegal anyway).
373  * 	Also works on type DNAME. Returns target name.
374  * @param dname: this pointer is updated to point into the cname rdata.
375  *	If a failsafe fails, nothing happens to the pointer (such as the
376  *	rdata was not a valid dname, not a CNAME, ...).
377  * @param dname_len: length of dname is returned.
378  */
379 void get_cname_target(struct ub_packed_rrset_key* rrset, uint8_t** dname,
380 	size_t* dname_len);
381 
382 /**
383  * Get a printable string for a rrset trust value
384  * @param s: rrset trust value
385  * @return printable string.
386  */
387 const char* rrset_trust_to_string(enum rrset_trust s);
388 
389 /**
390  * Get a printable string for a security status value
391  * @param s: security status
392  * @return printable string.
393  */
394 const char* sec_status_to_string(enum sec_status s);
395 
396 /**
397  * Print string with neat domain name, type, class from rrset.
398  * @param v: at what verbosity level to print this.
399  * @param str: string of message.
400  * @param rrset: structure with name, type and class.
401  */
402 void log_rrset_key(enum verbosity_value v, const char* str,
403 	struct ub_packed_rrset_key* rrset);
404 
405 /**
406  * Convert RR from RRset to string.
407  * @param rrset: structure with data.
408  * @param i: index of rr or RRSIG.
409  * @param now: time that is subtracted from ttl before printout. Can be 0.
410  * @param dest: destination string buffer. Must be nonNULL.
411  * @param dest_len: length of dest buffer (>0).
412  * @return false on failure.
413  */
414 int packed_rr_to_string(struct ub_packed_rrset_key* rrset, size_t i,
415 	time_t now, char* dest, size_t dest_len);
416 
417 /**
418  * Print the string with prefix, one rr per line.
419  * @param v: at what verbosity level to print this.
420  * @param str: string of message.
421  * @param rrset: with name, and rdata, and rrsigs.
422  */
423 void log_packed_rrset(enum verbosity_value v, const char* str,
424 	struct ub_packed_rrset_key* rrset);
425 
426 /**
427  * Allocate rrset in region - no more locks needed
428  * @param key: a (just from rrset cache looked up) rrset key + valid,
429  * 	packed data record.
430  * @param region: where to alloc the copy
431  * @param now: adjust the TTLs to be relative (subtract from all TTLs).
432  * @return new region-alloced rrset key or NULL on alloc failure.
433  */
434 struct ub_packed_rrset_key* packed_rrset_copy_region(
435 	struct ub_packed_rrset_key* key, struct regional* region,
436 	time_t now);
437 
438 /**
439  * Allocate rrset with malloc (from region or you are holding the lock).
440  * @param key: key with data entry.
441  * @param alloc: alloc_cache to create rrset_keys
442  * @param now: adjust the TTLs to be absolute (add to all TTLs).
443  * @return new region-alloced rrset key or NULL on alloc failure.
444  */
445 struct ub_packed_rrset_key* packed_rrset_copy_alloc(
446 	struct ub_packed_rrset_key* key, struct alloc_cache* alloc,
447 	time_t now);
448 
449 #endif /* UTIL_DATA_PACKED_RRSET_H */
450