1 /*
2  * iterator/iter_delegpt.h - delegation point with NS and address information.
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 implements the Delegation Point. It contains a list of name servers
40  * and their addresses if known.
41  */
42 
43 #ifndef ITERATOR_ITER_DELEGPT_H
44 #define ITERATOR_ITER_DELEGPT_H
45 #include "util/log.h"
46 struct regional;
47 struct delegpt_ns;
48 struct delegpt_addr;
49 struct dns_msg;
50 struct ub_packed_rrset_key;
51 struct msgreply_entry;
52 
53 /**
54  * Delegation Point.
55  * For a domain name, the NS rrset, and the A and AAAA records for those.
56  */
57 struct delegpt {
58 	/** the domain name of the delegation point. */
59 	uint8_t* name;
60 	/** length of the delegation point name */
61 	size_t namelen;
62 	/** number of labels in delegation point */
63 	int namelabs;
64 
65 	/** the nameservers, names from the NS RRset rdata. */
66 	struct delegpt_ns* nslist;
67 	/** the target addresses for delegation */
68 	struct delegpt_addr* target_list;
69 	/** the list of usable targets; subset of target_list
70 	 * the items in this list are not part of the result list.  */
71 	struct delegpt_addr* usable_list;
72 	/** the list of returned targets; subset of target_list */
73 	struct delegpt_addr* result_list;
74 
75 	/** if true, the NS RRset was bogus. All info is bad. */
76 	int bogus;
77 	/** if true, the parent-side NS record has been applied:
78 	 * its names have been added and their addresses can follow later.
79 	 * Also true if the delegationpoint was created from a delegation
80 	 * message and thus contains the parent-side-info already. */
81 	uint8_t has_parent_side_NS;
82 	/** for assertions on type of delegpt */
83 	uint8_t dp_type_mlc;
84 	/** use SSL for upstream query */
85 	uint8_t ssl_upstream;
86 	/** use TCP for upstream query */
87 	uint8_t tcp_upstream;
88 	/** delegpt from authoritative zone that is locally hosted */
89 	uint8_t auth_dp;
90 	/*** no cache */
91 	int no_cache;
92 };
93 
94 /**
95  * Nameservers for a delegation point.
96  */
97 struct delegpt_ns {
98 	/** next in list */
99 	struct delegpt_ns* next;
100 	/** name of nameserver */
101 	uint8_t* name;
102 	/** length of name */
103 	size_t namelen;
104 	/**
105 	 * If the name has been resolved. false if not queried for yet.
106 	 * true if the A, AAAA queries have been generated.
107 	 * marked true if those queries fail.
108 	 * and marked true if got4 and got6 are both true.
109 	 */
110 	int resolved;
111 	/** if the ipv4 address is in the delegpt, 0=not, 1=yes 2=negative,
112 	 * negative means it was done, but no content. */
113 	uint8_t got4;
114 	/** if the ipv6 address is in the delegpt, 0=not, 1=yes 2=negative */
115 	uint8_t got6;
116 	/**
117 	 * If the name is parent-side only and thus dispreferred.
118 	 * Its addresses become dispreferred as well
119 	 */
120 	uint8_t lame;
121 	/** if the parent-side ipv4 address has been looked up (last resort).
122 	 * Also enabled if a parent-side cache entry exists, or a parent-side
123 	 * negative-cache entry exists. */
124 	uint8_t done_pside4;
125 	/** if the parent-side ipv6 address has been looked up (last resort).
126 	 * Also enabled if a parent-side cache entry exists, or a parent-side
127 	 * negative-cache entry exists. */
128 	uint8_t done_pside6;
129 };
130 
131 /**
132  * Address of target nameserver in delegation point.
133  */
134 struct delegpt_addr {
135 	/** next delegation point in results */
136 	struct delegpt_addr* next_result;
137 	/** next delegation point in usable list */
138 	struct delegpt_addr* next_usable;
139 	/** next delegation point in all targets list */
140 	struct delegpt_addr* next_target;
141 
142 	/** delegation point address */
143 	struct sockaddr_storage addr;
144 	/** length of addr */
145 	socklen_t addrlen;
146 	/** number of attempts for this addr */
147 	int attempts;
148 	/** rtt stored here in the selection algorithm */
149 	int sel_rtt;
150 	/** if true, the A or AAAA RR was bogus, so this address is bad.
151 	 * Also check the dp->bogus to see if everything is bogus. */
152 	uint8_t bogus;
153 	/** if true, this address is dispreferred: it is a lame IP address */
154 	uint8_t lame;
155 	/** if the address is dnsseclame, but this cannot be cached, this
156 	 * option is useful to mark the address dnsseclame.
157 	 * This value is not copied in addr-copy and dp-copy. */
158 	uint8_t dnsseclame;
159 	/** the TLS authentication name, (if not NULL) to use. */
160 	char* tls_auth_name;
161 };
162 
163 /**
164  * Create new delegation point.
165  * @param regional: where to allocate it.
166  * @return new delegation point or NULL on error.
167  */
168 struct delegpt* delegpt_create(struct regional* regional);
169 
170 /**
171  * Create a copy of a delegation point.
172  * @param dp: delegation point to copy.
173  * @param regional: where to allocate it.
174  * @return new delegation point or NULL on error.
175  */
176 struct delegpt* delegpt_copy(struct delegpt* dp, struct regional* regional);
177 
178 /**
179  * Set name of delegation point.
180  * @param dp: delegation point.
181  * @param regional: where to allocate the name copy.
182  * @param name: name to use.
183  * @return false on error.
184  */
185 int delegpt_set_name(struct delegpt* dp, struct regional* regional,
186 	uint8_t* name);
187 
188 /**
189  * Add a name to the delegation point.
190  * @param dp: delegation point.
191  * @param regional: where to allocate the info.
192  * @param name: domain name in wire format.
193  * @param lame: name is lame, disprefer it.
194  * @return false on error.
195  */
196 int delegpt_add_ns(struct delegpt* dp, struct regional* regional,
197 	uint8_t* name, uint8_t lame);
198 
199 /**
200  * Add NS rrset; calls add_ns repeatedly.
201  * @param dp: delegation point.
202  * @param regional: where to allocate the info.
203  * @param ns_rrset: NS rrset.
204  * @param lame: rrset is lame, disprefer it.
205  * @return 0 on alloc error.
206  */
207 int delegpt_rrset_add_ns(struct delegpt* dp, struct regional* regional,
208 	struct ub_packed_rrset_key* ns_rrset, uint8_t lame);
209 
210 /**
211  * Add target address to the delegation point.
212  * @param dp: delegation point.
213  * @param regional: where to allocate the info.
214  * @param name: name for which target was found (must be in nslist).
215  *	This name is marked resolved.
216  * @param namelen: length of name.
217  * @param addr: the address.
218  * @param addrlen: the length of addr.
219  * @param bogus: security status for the address, pass true if bogus.
220  * @param lame: address is lame.
221  * @param additions: will be set to 1 if a new address is added
222  * @return false on error.
223  */
224 int delegpt_add_target(struct delegpt* dp, struct regional* regional,
225 	uint8_t* name, size_t namelen, struct sockaddr_storage* addr,
226 	socklen_t addrlen, uint8_t bogus, uint8_t lame, int* additions);
227 
228 /**
229  * Add A RRset to delegpt.
230  * @param dp: delegation point.
231  * @param regional: where to allocate the info.
232  * @param rrset: RRset A to add.
233  * @param lame: rrset is lame, disprefer it.
234  * @param additions: will be set to 1 if a new address is added
235  * @return 0 on alloc error.
236  */
237 int delegpt_add_rrset_A(struct delegpt* dp, struct regional* regional,
238 	struct ub_packed_rrset_key* rrset, uint8_t lame, int* additions);
239 
240 /**
241  * Add AAAA RRset to delegpt.
242  * @param dp: delegation point.
243  * @param regional: where to allocate the info.
244  * @param rrset: RRset AAAA to add.
245  * @param lame: rrset is lame, disprefer it.
246  * @param additions: will be set to 1 if a new address is added
247  * @return 0 on alloc error.
248  */
249 int delegpt_add_rrset_AAAA(struct delegpt* dp, struct regional* regional,
250 	struct ub_packed_rrset_key* rrset, uint8_t lame, int* additions);
251 
252 /**
253  * Add any RRset to delegpt.
254  * Does not check for duplicates added.
255  * @param dp: delegation point.
256  * @param regional: where to allocate the info.
257  * @param rrset: RRset to add, NS, A, AAAA.
258  * @param lame: rrset is lame, disprefer it.
259  * @param additions: will be set to 1 if a new address is added
260  * @return 0 on alloc error.
261  */
262 int delegpt_add_rrset(struct delegpt* dp, struct regional* regional,
263 	struct ub_packed_rrset_key* rrset, uint8_t lame, int* additions);
264 
265 /**
266  * Add address to the delegation point. No servername is associated or checked.
267  * @param dp: delegation point.
268  * @param regional: where to allocate the info.
269  * @param addr: the address.
270  * @param addrlen: the length of addr.
271  * @param bogus: if address is bogus.
272  * @param lame: if address is lame.
273  * @param tls_auth_name: TLS authentication name (or NULL).
274  * @param additions: will be set to 1 if a new address is added
275  * @return false on error.
276  */
277 int delegpt_add_addr(struct delegpt* dp, struct regional* regional,
278 	struct sockaddr_storage* addr, socklen_t addrlen,
279 	uint8_t bogus, uint8_t lame, char* tls_auth_name, int* additions);
280 
281 /**
282  * Find NS record in name list of delegation point.
283  * @param dp: delegation point.
284  * @param name: name of nameserver to look for, uncompressed wireformat.
285  * @param namelen: length of name.
286  * @return the ns structure or NULL if not found.
287  */
288 struct delegpt_ns* delegpt_find_ns(struct delegpt* dp, uint8_t* name,
289 	size_t namelen);
290 
291 /**
292  * Find address record in total list of delegation point.
293  * @param dp: delegation point.
294  * @param addr: address
295  * @param addrlen: length of addr
296  * @return the addr structure or NULL if not found.
297  */
298 struct delegpt_addr* delegpt_find_addr(struct delegpt* dp,
299 	struct sockaddr_storage* addr, socklen_t addrlen);
300 
301 /**
302  * Print the delegation point to the log. For debugging.
303  * @param v: verbosity value that is needed to emit to log.
304  * @param dp: delegation point.
305  */
306 void delegpt_log(enum verbosity_value v, struct delegpt* dp);
307 
308 /** count NS and number missing for logging */
309 void delegpt_count_ns(struct delegpt* dp, size_t* numns, size_t* missing);
310 
311 /** count addresses, and number in result and available lists, for logging */
312 void delegpt_count_addr(struct delegpt* dp, size_t* numaddr, size_t* numres,
313 	size_t* numavail);
314 
315 /**
316  * Add all usable targets to the result list.
317  * @param dp: delegation point.
318  */
319 void delegpt_add_unused_targets(struct delegpt* dp);
320 
321 /**
322  * Count number of missing targets. These are ns names with no resolved flag.
323  * @param dp: delegation point.
324  * @return number of missing targets (or 0).
325  */
326 size_t delegpt_count_missing_targets(struct delegpt* dp);
327 
328 /** count total number of targets in dp */
329 size_t delegpt_count_targets(struct delegpt* dp);
330 
331 /**
332  * Create new delegation point from a dns message
333  *
334  * Note that this method does not actually test to see if the message is an
335  * actual referral. It really is just checking to see if it can construct a
336  * delegation point, so the message could be of some other type (some ANSWER
337  * messages, some CNAME messages, generally.) Note that the resulting
338  * DelegationPoint will contain targets for all "relevant" glue (i.e.,
339  * address records whose ownernames match the target of one of the NS
340  * records), so if policy dictates that some glue should be discarded beyond
341  * that, discard it before calling this method. Note that this method will
342  * find "glue" in either the ADDITIONAL section or the ANSWER section.
343  *
344  * @param msg: the dns message, referral.
345  * @param regional: where to allocate delegation point.
346  * @return new delegation point or NULL on alloc error, or if the
347  *         message was not appropriate.
348  */
349 struct delegpt* delegpt_from_message(struct dns_msg* msg,
350 	struct regional* regional);
351 
352 /**
353  * Mark negative return in delegation point for specific nameserver.
354  * sets the got4 or got6 to negative, updates the ns->resolved.
355  * @param ns: the nameserver in the delegpt.
356  * @param qtype: A or AAAA (host order).
357  */
358 void delegpt_mark_neg(struct delegpt_ns* ns, uint16_t qtype);
359 
360 /**
361  * Add negative message to delegation point.
362  * @param dp: delegation point.
363  * @param msg: the message added, marks off A or AAAA from an NS entry.
364  */
365 void delegpt_add_neg_msg(struct delegpt* dp, struct msgreply_entry* msg);
366 
367 /**
368  * Register the fact that there is no ipv6 and thus AAAAs are not going
369  * to be queried for or be useful.
370  * @param dp: the delegation point. Updated to reflect no ipv6.
371  */
372 void delegpt_no_ipv6(struct delegpt* dp);
373 
374 /**
375  * Register the fact that there is no ipv4 and thus As are not going
376  * to be queried for or be useful.
377  * @param dp: the delegation point. Updated to reflect no ipv4.
378  */
379 void delegpt_no_ipv4(struct delegpt* dp);
380 
381 /**
382  * create malloced delegation point, with the given name
383  * @param name: uncompressed wireformat of delegpt name.
384  * @return NULL on alloc failure
385  */
386 struct delegpt* delegpt_create_mlc(uint8_t* name);
387 
388 /**
389  * free malloced delegation point.
390  * @param dp: must have been created with delegpt_create_mlc, free'd.
391  */
392 void delegpt_free_mlc(struct delegpt* dp);
393 
394 /**
395  * Set name of delegation point.
396  * @param dp: delegation point. malloced.
397  * @param name: name to use.
398  * @return false on error.
399  */
400 int delegpt_set_name_mlc(struct delegpt* dp, uint8_t* name);
401 
402 /**
403  * add a name to malloced delegation point.
404  * @param dp: must have been created with delegpt_create_mlc.
405  * @param name: the name to add.
406  * @param lame: the name is lame, disprefer.
407  * @return false on error.
408  */
409 int delegpt_add_ns_mlc(struct delegpt* dp, uint8_t* name, uint8_t lame);
410 
411 /**
412  * add an address to a malloced delegation point.
413  * @param dp: must have been created with delegpt_create_mlc.
414  * @param addr: the address.
415  * @param addrlen: the length of addr.
416  * @param bogus: if address is bogus.
417  * @param lame: if address is lame.
418  * @param tls_auth_name: TLS authentication name (or NULL).
419  * @return false on error.
420  */
421 int delegpt_add_addr_mlc(struct delegpt* dp, struct sockaddr_storage* addr,
422 	socklen_t addrlen, uint8_t bogus, uint8_t lame, char* tls_auth_name);
423 
424 /**
425  * Add target address to the delegation point.
426  * @param dp: must have been created with delegpt_create_mlc.
427  * @param name: name for which target was found (must be in nslist).
428  *	This name is marked resolved.
429  * @param namelen: length of name.
430  * @param addr: the address.
431  * @param addrlen: the length of addr.
432  * @param bogus: security status for the address, pass true if bogus.
433  * @param lame: address is lame.
434  * @return false on error.
435  */
436 int delegpt_add_target_mlc(struct delegpt* dp, uint8_t* name, size_t namelen,
437 	struct sockaddr_storage* addr, socklen_t addrlen, uint8_t bogus,
438 	uint8_t lame);
439 
440 /** get memory in use by dp */
441 size_t delegpt_get_mem(struct delegpt* dp);
442 
443 #endif /* ITERATOR_ITER_DELEGPT_H */
444