xref: /freebsd/contrib/unbound/util/data/packed_rrset.h (revision 46d2f61818f594174cafe31ee338c6e083fa1876)
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 /** This rrset is from RPZ. It is not real, it is synthesized data to block
65  * access. The flag makes lookups, from cache in iterator, ignore the fake
66  * items and only use actual data.  Eg. when the iterator looksup NS, CNAME,
67  * A and AAAA types, it then gets items without this flag that are the
68  * actual network. But messages with these records in it can be stored in
69  * the cache and retrieved for a reply. */
70 #define PACKED_RRSET_RPZ 0x8
71 /** this rrset is A/AAAA and is an unverified glue record */
72 #define PACKED_RRSET_UNVERIFIED_GLUE 0x10
73 
74 /** number of rrs and rrsets for integer overflow protection.  More than
75  * this is not really possible (64K packet has much less RRs and RRsets) in
76  * a message.  And this is small enough that also multiplied there is no
77  * integer overflow. */
78 #define RR_COUNT_MAX 0xffffff
79 
80 /**
81  * The identifying information for an RRset.
82  */
83 struct packed_rrset_key {
84 	/**
85 	 * The domain name. If not null (for id=0) it is allocated, and
86 	 * contains the wireformat domain name.
87 	 * This dname is not canonicalized.
88 	 */
89 	uint8_t* dname;
90 	/**
91 	 * Length of the domain name, including last 0 root octet.
92 	 */
93 	size_t dname_len;
94 	/**
95 	 * Flags. 32bit to be easy for hashing:
96 	 * 	o PACKED_RRSET_NSEC_AT_APEX
97 	 * 	o PACKED_RRSET_PARENT_SIDE
98 	 * 	o PACKED_RRSET_SOA_NEG
99 	 * 	o PACKED_RRSET_FIXEDTTL (not supposed to be cached)
100 	 * 	o PACKED_RRSET_RPZ
101 	 * 	o PACKED_RRSET_UNVERIFIED_GLUE
102 	 */
103 	uint32_t flags;
104 	/** the rrset type in network format */
105 	uint16_t type;
106 	/** the rrset class in network format */
107 	uint16_t rrset_class;
108 };
109 
110 /**
111  * This structure contains an RRset. A set of resource records that
112  * share the same domain name, type and class.
113  *
114  * Due to memory management and threading, the key structure cannot be
115  * deleted, although the data can be. The id can be set to 0 to store and the
116  * structure can be recycled with a new id.
117  */
118 struct ub_packed_rrset_key {
119 	/**
120 	 * entry into hashtable. Note the lock is never destroyed,
121 	 *  even when this key is retired to the cache.
122 	 * the data pointer (if not null) points to a struct packed_rrset.
123 	 */
124 	struct lruhash_entry entry;
125 	/**
126 	 * the ID of this rrset. unique, based on threadid + sequenceno.
127 	 * ids are not reused, except after flushing the cache.
128 	 * zero is an unused entry, and never a valid id.
129 	 * Check this value after getting entry.lock.
130 	 * The other values in this struct may only be altered after changing
131 	 * the id (which needs a writelock on entry.lock).
132 	 */
133 	rrset_id_type id;
134 	/** key data: dname, type and class */
135 	struct packed_rrset_key rk;
136 };
137 
138 /**
139  * RRset trustworthiness. Bigger value is more trust. RFC 2181.
140  * The rrset_trust_add_noAA, rrset_trust_auth_noAA, rrset_trust_add_AA,
141  * are mentioned as the same trustworthiness in 2181, but split up here
142  * for ease of processing.
143  *
144  * rrset_trust_nonauth_ans_AA, rrset_trust_ans_noAA
145  * are also mentioned as the same trustworthiness in 2181, but split up here
146  * for ease of processing.
147  *
148  * Added trust_none for a sane initial value, smaller than anything else.
149  * Added validated and ultimate trust for keys and rrsig validated content.
150  */
151 enum rrset_trust {
152 	/** initial value for trust */
153 	rrset_trust_none = 0,
154 	/** Additional information from non-authoritative answers */
155 	rrset_trust_add_noAA,
156 	/** Data from the authority section of a non-authoritative answer */
157 	rrset_trust_auth_noAA,
158 	/** Additional information from an authoritative answer */
159 	rrset_trust_add_AA,
160 	/** non-authoritative data from the answer section of authoritative
161 	 * answers */
162 	rrset_trust_nonauth_ans_AA,
163 	/** Data from the answer section of a non-authoritative answer */
164 	rrset_trust_ans_noAA,
165 	/** Glue from a primary zone, or glue from a zone transfer */
166 	rrset_trust_glue,
167 	/** Data from the authority section of an authoritative answer */
168 	rrset_trust_auth_AA,
169 	/** The authoritative data included in the answer section of an
170 	 *  authoritative reply */
171 	rrset_trust_ans_AA,
172 	/** Data from a zone transfer, other than glue */
173 	rrset_trust_sec_noglue,
174 	/** Data from a primary zone file, other than glue data */
175 	rrset_trust_prim_noglue,
176 	/** DNSSEC(rfc4034) validated with trusted keys */
177 	rrset_trust_validated,
178 	/** ultimately trusted, no more trust is possible;
179 	 * trusted keys from the unbound configuration setup. */
180 	rrset_trust_ultimate
181 };
182 
183 /**
184  * Security status from validation for data.
185  * The order is significant; more secure, more proven later.
186  */
187 enum sec_status {
188 	/** UNCHECKED means that object has yet to be validated. */
189 	sec_status_unchecked = 0,
190 	/** BOGUS means that the object (RRset or message) failed to validate
191 	 *  (according to local policy), but should have validated. */
192 	sec_status_bogus,
193 	/** INDETERMINATE means that the object is insecure, but not
194 	 * authoritatively so. Generally this means that the RRset is not
195 	 * below a configured trust anchor. */
196 	sec_status_indeterminate,
197 	/** INSECURE means that the object is authoritatively known to be
198 	 * insecure. Generally this means that this RRset is below a trust
199 	 * anchor, but also below a verified, insecure delegation. */
200 	sec_status_insecure,
201 	/** SECURE_SENTINEL_FAIL means that the object (RRset or message)
202 	 * validated according to local policy but did not succeed in the root
203 	 * KSK sentinel test (draft-ietf-dnsop-kskroll-sentinel). */
204 	sec_status_secure_sentinel_fail,
205 	/** SECURE means that the object (RRset or message) validated
206 	 * according to local policy. */
207 	sec_status_secure
208 };
209 
210 /**
211  * RRset data.
212  *
213  * The data is packed, stored contiguously in memory.
214  *
215  * It is not always stored contiguously, in that case, an unpacked-packed
216  * rrset has the arrays separate.  A bunch of routines work on that, but
217  * the packed rrset that is contiguous is for the rrset-cache and the
218  * cache-response routines in daemon/worker.c.
219  *
220  * memory layout:
221  *	o base struct
222  *	o rr_len size_t array
223  *	o rr_data uint8_t* array
224  *	o rr_ttl time_t array (after size_t and ptrs because those may be
225  *		64bit and this array before those would make them unaligned).
226  *		Since the stuff before is 32/64bit, rr_ttl is 32 bit aligned.
227  *	o rr_data rdata wireformats
228  *	o rrsig_data rdata wireformat(s)
229  *
230  * Rdata is stored in wireformat. The dname is stored in wireformat.
231  * TTLs are stored as absolute values (and could be expired).
232  *
233  * RRSIGs are stored in the arrays after the regular rrs.
234  *
235  * You need the packed_rrset_key to know dname, type, class of the
236  * resource records in this RRset. (if signed the rrsig gives the type too).
237  *
238  * On the wire an RR is:
239  *	name, type, class, ttl, rdlength, rdata.
240  * So we need to send the following per RR:
241  *	key.dname, ttl, rr_data[i].
242  *	since key.dname ends with type and class.
243  *	and rr_data starts with the rdlength.
244  *	the ttl value to send changes due to time.
245  */
246 struct packed_rrset_data {
247 	/** Timestamp added to TTLs in the packed data.
248 	 * Needed to support serving original TTLs. */
249 	time_t ttl_add;
250 	/** TTL (in seconds like time()) of the rrset.
251 	 * Same for all RRs see rfc2181(5.2).  */
252 	time_t ttl;
253 	/** number of rrs. */
254 	size_t count;
255 	/** number of rrsigs, if 0 no rrsigs */
256 	size_t rrsig_count;
257 	/** the trustworthiness of the rrset data */
258 	enum rrset_trust trust;
259 	/** security status of the rrset data */
260 	enum sec_status security;
261 	/** length of every rr's rdata, rr_len[i] is size of rr_data[i]. */
262 	size_t* rr_len;
263 	/** ttl of every rr. rr_ttl[i] ttl of rr i. */
264 	time_t *rr_ttl;
265 	/**
266 	 * Array of pointers to every rr's rdata.
267 	 * The rr_data[i] rdata is stored in uncompressed wireformat.
268 	 * The first uint16_t of rr_data[i] is network format rdlength.
269 	 *
270 	 * rr_data[count] to rr_data[count+rrsig_count] contain the rrsig data.
271 	 */
272 	uint8_t** rr_data;
273 };
274 
275 /**
276  * An RRset can be represented using both key and data together.
277  * Split into key and data structures to simplify implementation of
278  * caching schemes.
279  */
280 struct packed_rrset {
281 	/** domain name, type and class */
282 	struct packed_rrset_key* k;
283 	/** ttl, count and rdatas (and rrsig) */
284 	struct packed_rrset_data* d;
285 };
286 
287 /**
288  * list of packed rrsets
289  */
290 struct packed_rrset_list {
291 	/** next in list */
292 	struct packed_rrset_list* next;
293 	/** rrset key and data */
294 	struct packed_rrset rrset;
295 };
296 
297 /**
298  * Delete packed rrset key and data, not entered in hashtables yet.
299  * Used during parsing.
300  * @param pkey: rrset key structure with locks, key and data pointers.
301  * @param alloc: where to return the unfree-able key structure.
302  */
303 void ub_packed_rrset_parsedelete(struct ub_packed_rrset_key* pkey,
304 	struct alloc_cache* alloc);
305 
306 /**
307  * Memory size of rrset data. RRset data must be filled in correctly.
308  * @param data: data to examine.
309  * @return size in bytes.
310  */
311 size_t packed_rrset_sizeof(struct packed_rrset_data* data);
312 
313 /**
314  * Get TTL of rrset. RRset data must be filled in correctly.
315  * @param key: rrset key, with data to examine.
316  * @return ttl value.
317  */
318 time_t ub_packed_rrset_ttl(struct ub_packed_rrset_key* key);
319 
320 /**
321  * Calculate memory size of rrset entry. For hash table usage.
322  * @param key: struct ub_packed_rrset_key*.
323  * @param data: struct packed_rrset_data*.
324  * @return size in bytes.
325  */
326 size_t ub_rrset_sizefunc(void* key, void* data);
327 
328 /**
329  * compares two rrset keys.
330  * @param k1: struct ub_packed_rrset_key*.
331  * @param k2: struct ub_packed_rrset_key*.
332  * @return 0 if equal.
333  */
334 int ub_rrset_compare(void* k1, void* k2);
335 
336 /**
337  * compare two rrset data structures.
338  * Compared rdata and rrsigdata, not the trust or ttl value.
339  * @param d1: data to compare.
340  * @param d2: data to compare.
341  * @return 1 if equal.
342  */
343 int rrsetdata_equal(struct packed_rrset_data* d1, struct packed_rrset_data* d2);
344 
345 /**
346  * Old key to be deleted. RRset keys are recycled via alloc.
347  * The id is set to 0. So that other threads, after acquiring a lock always
348  * get the correct value, in this case the 0 deleted-special value.
349  * @param key: struct ub_packed_rrset_key*.
350  * @param userdata: alloc structure to use for recycling.
351  */
352 void ub_rrset_key_delete(void* key, void* userdata);
353 
354 /**
355  * Old data to be deleted.
356  * @param data: what to delete.
357  * @param userdata: user data ptr.
358  */
359 void rrset_data_delete(void* data, void* userdata);
360 
361 /**
362  * Calculate hash value for a packed rrset key.
363  * @param key: the rrset key with name, type, class, flags.
364  * @return hash value.
365  */
366 hashvalue_type rrset_key_hash(struct packed_rrset_key* key);
367 
368 /**
369  * Fixup pointers in fixed data packed_rrset_data blob.
370  * After a memcpy of the data for example. Will set internal pointers right.
371  * @param data: rrset data structure. Otherwise correctly filled in.
372  */
373 void packed_rrset_ptr_fixup(struct packed_rrset_data* data);
374 
375 /**
376  * Fixup TTLs in fixed data packed_rrset_data blob.
377  * @param data: rrset data structure. Otherwise correctly filled in.
378  * @param add: how many seconds to add, pass time(0) for example.
379  */
380 void packed_rrset_ttl_add(struct packed_rrset_data* data, time_t add);
381 
382 /**
383  * Utility procedure to extract CNAME target name from its rdata.
384  * Failsafes; it will change passed dname to a valid dname or do nothing.
385  * @param rrset: the rrset structure. Must be a CNAME.
386  *	Only first RR is used (multiple RRs are technically illegal anyway).
387  * 	Also works on type DNAME. Returns target name.
388  * @param dname: this pointer is updated to point into the cname rdata.
389  *	If a failsafe fails, nothing happens to the pointer (such as the
390  *	rdata was not a valid dname, not a CNAME, ...).
391  * @param dname_len: length of dname is returned.
392  */
393 void get_cname_target(struct ub_packed_rrset_key* rrset, uint8_t** dname,
394 	size_t* dname_len);
395 
396 /**
397  * Get a printable string for a rrset trust value
398  * @param s: rrset trust value
399  * @return printable string.
400  */
401 const char* rrset_trust_to_string(enum rrset_trust s);
402 
403 /**
404  * Get a printable string for a security status value
405  * @param s: security status
406  * @return printable string.
407  */
408 const char* sec_status_to_string(enum sec_status s);
409 
410 /**
411  * Print string with neat domain name, type, class from rrset.
412  * @param v: at what verbosity level to print this.
413  * @param str: string of message.
414  * @param rrset: structure with name, type and class.
415  */
416 void log_rrset_key(enum verbosity_value v, const char* str,
417 	struct ub_packed_rrset_key* rrset);
418 
419 /**
420  * Convert RR from RRset to string.
421  * @param rrset: structure with data.
422  * @param i: index of rr or RRSIG.
423  * @param now: time that is subtracted from ttl before printout. Can be 0.
424  * @param dest: destination string buffer. Must be nonNULL.
425  * @param dest_len: length of dest buffer (>0).
426  * @return false on failure.
427  */
428 int packed_rr_to_string(struct ub_packed_rrset_key* rrset, size_t i,
429 	time_t now, char* dest, size_t dest_len);
430 
431 /**
432  * Print the string with prefix, one rr per line.
433  * @param v: at what verbosity level to print this.
434  * @param str: string of message.
435  * @param rrset: with name, and rdata, and rrsigs.
436  */
437 void log_packed_rrset(enum verbosity_value v, const char* str,
438 	struct ub_packed_rrset_key* rrset);
439 
440 /**
441  * Allocate rrset in region - no more locks needed
442  * @param key: a (just from rrset cache looked up) rrset key + valid,
443  * 	packed data record.
444  * @param region: where to alloc the copy
445  * @param now: adjust the TTLs to be relative (subtract from all TTLs).
446  * @return new region-alloced rrset key or NULL on alloc failure.
447  */
448 struct ub_packed_rrset_key* packed_rrset_copy_region(
449 	struct ub_packed_rrset_key* key, struct regional* region,
450 	time_t now);
451 
452 /**
453  * Allocate rrset with malloc (from region or you are holding the lock).
454  * @param key: key with data entry.
455  * @param alloc: alloc_cache to create rrset_keys
456  * @param now: adjust the TTLs to be absolute (add to all TTLs).
457  * @return new region-alloced rrset key or NULL on alloc failure.
458  */
459 struct ub_packed_rrset_key* packed_rrset_copy_alloc(
460 	struct ub_packed_rrset_key* key, struct alloc_cache* alloc,
461 	time_t now);
462 
463 /**
464  * Find RR index in packed rrset
465  * Raw comparison, does not canonicalize RDATA
466  * @param d: packed rrset
467  * @param rdata: RDATA of RR to find
468  * @param len: length of rdata
469  * @param index: pointer to int to store index of found RR
470  * @return 1 if RR found, 0 otherwise
471  */
472 int
473 packed_rrset_find_rr(struct packed_rrset_data* d, uint8_t* rdata, size_t len,
474 	size_t* index);
475 
476 #endif /* UTIL_DATA_PACKED_RRSET_H */
477