xref: /freebsd/contrib/unbound/iterator/iterator.h (revision 5469a9953005a9a4d4aad7be88545d441622e9a0)
1b7579f77SDag-Erling Smørgrav /*
2b7579f77SDag-Erling Smørgrav  * iterator/iterator.h - iterative resolver DNS query response module
3b7579f77SDag-Erling Smørgrav  *
4b7579f77SDag-Erling Smørgrav  * Copyright (c) 2007, NLnet Labs. All rights reserved.
5b7579f77SDag-Erling Smørgrav  *
6b7579f77SDag-Erling Smørgrav  * This software is open source.
7b7579f77SDag-Erling Smørgrav  *
8b7579f77SDag-Erling Smørgrav  * Redistribution and use in source and binary forms, with or without
9b7579f77SDag-Erling Smørgrav  * modification, are permitted provided that the following conditions
10b7579f77SDag-Erling Smørgrav  * are met:
11b7579f77SDag-Erling Smørgrav  *
12b7579f77SDag-Erling Smørgrav  * Redistributions of source code must retain the above copyright notice,
13b7579f77SDag-Erling Smørgrav  * this list of conditions and the following disclaimer.
14b7579f77SDag-Erling Smørgrav  *
15b7579f77SDag-Erling Smørgrav  * Redistributions in binary form must reproduce the above copyright notice,
16b7579f77SDag-Erling Smørgrav  * this list of conditions and the following disclaimer in the documentation
17b7579f77SDag-Erling Smørgrav  * and/or other materials provided with the distribution.
18b7579f77SDag-Erling Smørgrav  *
19b7579f77SDag-Erling Smørgrav  * Neither the name of the NLNET LABS nor the names of its contributors may
20b7579f77SDag-Erling Smørgrav  * be used to endorse or promote products derived from this software without
21b7579f77SDag-Erling Smørgrav  * specific prior written permission.
22b7579f77SDag-Erling Smørgrav  *
23b7579f77SDag-Erling Smørgrav  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
2417d15b25SDag-Erling Smørgrav  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
2517d15b25SDag-Erling Smørgrav  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
2617d15b25SDag-Erling Smørgrav  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
2717d15b25SDag-Erling Smørgrav  * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
2817d15b25SDag-Erling Smørgrav  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
2917d15b25SDag-Erling Smørgrav  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
3017d15b25SDag-Erling Smørgrav  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
3117d15b25SDag-Erling Smørgrav  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
3217d15b25SDag-Erling Smørgrav  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
3317d15b25SDag-Erling Smørgrav  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34b7579f77SDag-Erling Smørgrav  */
35b7579f77SDag-Erling Smørgrav 
36b7579f77SDag-Erling Smørgrav /**
37b7579f77SDag-Erling Smørgrav  * \file
38b7579f77SDag-Erling Smørgrav  *
398a384985SDag-Erling Smørgrav  * This file contains a module that performs recursive iterative DNS query
40b7579f77SDag-Erling Smørgrav  * processing.
41b7579f77SDag-Erling Smørgrav  */
42b7579f77SDag-Erling Smørgrav 
43b7579f77SDag-Erling Smørgrav #ifndef ITERATOR_ITERATOR_H
44b7579f77SDag-Erling Smørgrav #define ITERATOR_ITERATOR_H
45b7579f77SDag-Erling Smørgrav #include "services/outbound_list.h"
46b7579f77SDag-Erling Smørgrav #include "util/data/msgreply.h"
47b7579f77SDag-Erling Smørgrav #include "util/module.h"
48b7579f77SDag-Erling Smørgrav struct delegpt;
49b7579f77SDag-Erling Smørgrav struct iter_hints;
50b7579f77SDag-Erling Smørgrav struct iter_forwards;
51b7579f77SDag-Erling Smørgrav struct iter_donotq;
52b7579f77SDag-Erling Smørgrav struct iter_prep_list;
53b7579f77SDag-Erling Smørgrav struct iter_priv;
543005e0a3SDag-Erling Smørgrav struct rbtree_type;
55b7579f77SDag-Erling Smørgrav 
5652df462fSXin LI /** max number of targets spawned for a query and its subqueries */
57b75612f8SDag-Erling Smørgrav #define MAX_TARGET_COUNT	64
58091e9e46SCy Schubert /** max number of target lookups per qstate, per delegation point */
59091e9e46SCy Schubert #define MAX_DP_TARGET_COUNT	16
60091e9e46SCy Schubert /** max number of nxdomains allowed for target lookups for a query and
61091e9e46SCy Schubert  * its subqueries */
62091e9e46SCy Schubert #define MAX_TARGET_NX		5
63b7579f77SDag-Erling Smørgrav /** max number of query restarts. Determines max number of CNAME chain. */
64*5469a995SCy Schubert #define MAX_RESTART_COUNT	11
65b7579f77SDag-Erling Smørgrav /** max number of referrals. Makes sure resolver does not run away */
66b7579f77SDag-Erling Smørgrav #define MAX_REFERRAL_COUNT	130
67b7579f77SDag-Erling Smørgrav /** max number of queries-sent-out.  Make sure large NS set does not loop */
68ff825849SDag-Erling Smørgrav #define MAX_SENT_COUNT		32
69e2d15004SDag-Erling Smørgrav /** max number of queries for which to perform dnsseclameness detection,
708a384985SDag-Erling Smørgrav  * (rrsigs missing detection) after that, just pick up that response */
71e2d15004SDag-Erling Smørgrav #define DNSSEC_LAME_DETECT_COUNT 4
72e2d15004SDag-Erling Smørgrav /**
73e2d15004SDag-Erling Smørgrav  * max number of QNAME minimisation iterations. Limits number of queries for
74e2d15004SDag-Erling Smørgrav  * QNAMEs with a lot of labels.
75e2d15004SDag-Erling Smørgrav */
76e2d15004SDag-Erling Smørgrav #define MAX_MINIMISE_COUNT	10
77b5663de9SDag-Erling Smørgrav /* max number of time-outs for minimised query. Prevents resolving failures
78b5663de9SDag-Erling Smørgrav  * when the QNAME minimisation QTYPE is blocked. */
79b5663de9SDag-Erling Smørgrav #define MAX_MINIMISE_TIMEOUT_COUNT 3
80e2d15004SDag-Erling Smørgrav /**
81e2d15004SDag-Erling Smørgrav  * number of labels from QNAME that are always send individually when using
82e2d15004SDag-Erling Smørgrav  * QNAME minimisation, even when the number of labels of the QNAME is bigger
83e2d15004SDag-Erling Smørgrav  * tham MAX_MINIMISE_COUNT */
84e2d15004SDag-Erling Smørgrav #define MINIMISE_ONE_LAB	4
85e2d15004SDag-Erling Smørgrav #define MINIMISE_MULTIPLE_LABS	(MAX_MINIMISE_COUNT - MINIMISE_ONE_LAB)
86b7579f77SDag-Erling Smørgrav /** at what query-sent-count to stop target fetch policy */
87b7579f77SDag-Erling Smørgrav #define TARGET_FETCH_STOP	3
88b7579f77SDag-Erling Smørgrav /** how nice is a server without further information, in msec
89b7579f77SDag-Erling Smørgrav  * Equals rtt initial timeout value.
90b7579f77SDag-Erling Smørgrav  */
91e86b9096SDag-Erling Smørgrav extern int UNKNOWN_SERVER_NICENESS;
92b7579f77SDag-Erling Smørgrav /** maximum timeout before a host is deemed unsuitable, in msec.
93b7579f77SDag-Erling Smørgrav  * After host_ttl this will be timed out and the host will be tried again.
94b7579f77SDag-Erling Smørgrav  * Equals RTT_MAX_TIMEOUT
95b7579f77SDag-Erling Smørgrav  */
96b7579f77SDag-Erling Smørgrav #define USEFUL_SERVER_TOP_TIMEOUT	120000
97b7579f77SDag-Erling Smørgrav /** number of retries on outgoing queries */
98b7579f77SDag-Erling Smørgrav #define OUTBOUND_MSG_RETRY 5
99b7579f77SDag-Erling Smørgrav /** RTT band, within this amount from the best, servers are chosen randomly.
100b7579f77SDag-Erling Smørgrav  * Chosen so that the UNKNOWN_SERVER_NICENESS falls within the band of a
101b7579f77SDag-Erling Smørgrav  * fast server, this causes server exploration as a side benefit. msec. */
102b7579f77SDag-Erling Smørgrav #define RTT_BAND 400
103b7579f77SDag-Erling Smørgrav /** Start value for blacklisting a host, 2*USEFUL_SERVER_TOP_TIMEOUT in sec */
104b7579f77SDag-Erling Smørgrav #define INFRA_BACKOFF_INITIAL 240
105b7579f77SDag-Erling Smørgrav 
106b7579f77SDag-Erling Smørgrav /**
107b7579f77SDag-Erling Smørgrav  * Global state for the iterator.
108b7579f77SDag-Erling Smørgrav  */
109b7579f77SDag-Erling Smørgrav struct iter_env {
110b7579f77SDag-Erling Smørgrav 	/** A flag to indicate whether or not we have an IPv6 route */
111b7579f77SDag-Erling Smørgrav 	int supports_ipv6;
112b7579f77SDag-Erling Smørgrav 
113b7579f77SDag-Erling Smørgrav 	/** A flag to indicate whether or not we have an IPv4 route */
114b7579f77SDag-Erling Smørgrav 	int supports_ipv4;
115b7579f77SDag-Erling Smørgrav 
116b7579f77SDag-Erling Smørgrav 	/** A set of inetaddrs that should never be queried. */
117b7579f77SDag-Erling Smørgrav 	struct iter_donotq* donotq;
118b7579f77SDag-Erling Smørgrav 
119b7579f77SDag-Erling Smørgrav 	/** private address space and private domains */
120b7579f77SDag-Erling Smørgrav 	struct iter_priv* priv;
121b7579f77SDag-Erling Smørgrav 
12209a3aaf3SDag-Erling Smørgrav 	/** whitelist for capsforid names */
1233005e0a3SDag-Erling Smørgrav 	struct rbtree_type* caps_white;
12409a3aaf3SDag-Erling Smørgrav 
125b7579f77SDag-Erling Smørgrav 	/** The maximum dependency depth that this resolver will pursue. */
126b7579f77SDag-Erling Smørgrav 	int max_dependency_depth;
127b7579f77SDag-Erling Smørgrav 
128b7579f77SDag-Erling Smørgrav 	/**
129b7579f77SDag-Erling Smørgrav 	 * The target fetch policy for each dependency level. This is
130b7579f77SDag-Erling Smørgrav 	 * described as a simple number (per dependency level):
131b7579f77SDag-Erling Smørgrav 	 *	negative numbers (usually just -1) mean fetch-all,
132b7579f77SDag-Erling Smørgrav 	 *	0 means only fetch on demand, and
133b7579f77SDag-Erling Smørgrav 	 *	positive numbers mean to fetch at most that many targets.
134b7579f77SDag-Erling Smørgrav 	 * array of max_dependency_depth+1 size.
135b7579f77SDag-Erling Smørgrav 	 */
136b7579f77SDag-Erling Smørgrav 	int* target_fetch_policy;
13705ab2901SDag-Erling Smørgrav 
138971980c3SDag-Erling Smørgrav 	/** lock on ratelimit counter */
139971980c3SDag-Erling Smørgrav 	lock_basic_type queries_ratelimit_lock;
140971980c3SDag-Erling Smørgrav 	/** number of queries that have been ratelimited */
141971980c3SDag-Erling Smørgrav 	size_t num_queries_ratelimited;
14205ab2901SDag-Erling Smørgrav };
14305ab2901SDag-Erling Smørgrav 
14405ab2901SDag-Erling Smørgrav /**
14505ab2901SDag-Erling Smørgrav  * QNAME minimisation state
14605ab2901SDag-Erling Smørgrav  */
14705ab2901SDag-Erling Smørgrav enum minimisation_state {
14805ab2901SDag-Erling Smørgrav 	/**
14905ab2901SDag-Erling Smørgrav 	 * (Re)start minimisation. Outgoing QNAME should be set to dp->name.
1508a384985SDag-Erling Smørgrav 	 * State entered on new query or after following referral or CNAME.
15105ab2901SDag-Erling Smørgrav 	 */
15205ab2901SDag-Erling Smørgrav 	INIT_MINIMISE_STATE = 0,
15305ab2901SDag-Erling Smørgrav 	/**
1548a384985SDag-Erling Smørgrav 	 * QNAME minimisation ongoing. Increase QNAME on every iteration.
15505ab2901SDag-Erling Smørgrav 	 */
15605ab2901SDag-Erling Smørgrav 	MINIMISE_STATE,
15705ab2901SDag-Erling Smørgrav 	/**
15805ab2901SDag-Erling Smørgrav 	 * Don't increment QNAME this iteration
15905ab2901SDag-Erling Smørgrav 	 */
16005ab2901SDag-Erling Smørgrav 	SKIP_MINIMISE_STATE,
16105ab2901SDag-Erling Smørgrav 	/**
16205ab2901SDag-Erling Smørgrav 	 * Send out full QNAME + original QTYPE
16305ab2901SDag-Erling Smørgrav 	 */
16405ab2901SDag-Erling Smørgrav 	DONOT_MINIMISE_STATE,
165b7579f77SDag-Erling Smørgrav };
166b7579f77SDag-Erling Smørgrav 
167b7579f77SDag-Erling Smørgrav /**
168b7579f77SDag-Erling Smørgrav  * State of the iterator for a query.
169b7579f77SDag-Erling Smørgrav  */
170b7579f77SDag-Erling Smørgrav enum iter_state {
171b7579f77SDag-Erling Smørgrav 	/**
172b7579f77SDag-Erling Smørgrav 	 * Externally generated queries start at this state. Query restarts are
173b7579f77SDag-Erling Smørgrav 	 * reset to this state.
174b7579f77SDag-Erling Smørgrav 	 */
175b7579f77SDag-Erling Smørgrav 	INIT_REQUEST_STATE = 0,
176b7579f77SDag-Erling Smørgrav 
177b7579f77SDag-Erling Smørgrav 	/**
178b7579f77SDag-Erling Smørgrav 	 * Root priming events reactivate here, most other events pass
179b7579f77SDag-Erling Smørgrav 	 * through this naturally as the 2nd part of the INIT_REQUEST_STATE.
180b7579f77SDag-Erling Smørgrav 	 */
181b7579f77SDag-Erling Smørgrav 	INIT_REQUEST_2_STATE,
182b7579f77SDag-Erling Smørgrav 
183b7579f77SDag-Erling Smørgrav 	/**
184b7579f77SDag-Erling Smørgrav 	 * Stub priming events reactivate here, most other events pass
185b7579f77SDag-Erling Smørgrav 	 * through this naturally as the 3rd part of the INIT_REQUEST_STATE.
186b7579f77SDag-Erling Smørgrav 	 */
187b7579f77SDag-Erling Smørgrav 	INIT_REQUEST_3_STATE,
188b7579f77SDag-Erling Smørgrav 
189b7579f77SDag-Erling Smørgrav 	/**
190b7579f77SDag-Erling Smørgrav 	 * Each time a delegation point changes for a given query or a
191b7579f77SDag-Erling Smørgrav 	 * query times out and/or wakes up, this state is (re)visited.
1928a384985SDag-Erling Smørgrav 	 * This state is responsible for iterating through a list of
193b7579f77SDag-Erling Smørgrav 	 * nameserver targets.
194b7579f77SDag-Erling Smørgrav 	 */
195b7579f77SDag-Erling Smørgrav 	QUERYTARGETS_STATE,
196b7579f77SDag-Erling Smørgrav 
197b7579f77SDag-Erling Smørgrav 	/**
198b7579f77SDag-Erling Smørgrav 	 * Responses to queries start at this state. This state handles
199b7579f77SDag-Erling Smørgrav 	 * the decision tree associated with handling responses.
200b7579f77SDag-Erling Smørgrav 	 */
201b7579f77SDag-Erling Smørgrav 	QUERY_RESP_STATE,
202b7579f77SDag-Erling Smørgrav 
203b7579f77SDag-Erling Smørgrav 	/** Responses to priming queries finish at this state. */
204b7579f77SDag-Erling Smørgrav 	PRIME_RESP_STATE,
205b7579f77SDag-Erling Smørgrav 
206b7579f77SDag-Erling Smørgrav 	/** Collecting query class information, for qclass=ANY, when
207b7579f77SDag-Erling Smørgrav 	 * it spawns off queries for every class, it returns here. */
208b7579f77SDag-Erling Smørgrav 	COLLECT_CLASS_STATE,
209b7579f77SDag-Erling Smørgrav 
210b7579f77SDag-Erling Smørgrav 	/** Find NS record to resolve DS record from, walking to the right
211b7579f77SDag-Erling Smørgrav 	 * NS spot until we find it */
212b7579f77SDag-Erling Smørgrav 	DSNS_FIND_STATE,
213b7579f77SDag-Erling Smørgrav 
214b7579f77SDag-Erling Smørgrav 	/** Responses that are to be returned upstream end at this state.
215b7579f77SDag-Erling Smørgrav 	 * As well as responses to target queries. */
216b7579f77SDag-Erling Smørgrav 	FINISHED_STATE
217b7579f77SDag-Erling Smørgrav };
218b7579f77SDag-Erling Smørgrav 
219b7579f77SDag-Erling Smørgrav /**
220b7579f77SDag-Erling Smørgrav  * Per query state for the iterator module.
221b7579f77SDag-Erling Smørgrav  */
222b7579f77SDag-Erling Smørgrav struct iter_qstate {
223b7579f77SDag-Erling Smørgrav 	/**
224b7579f77SDag-Erling Smørgrav 	 * State of the iterator module.
225b7579f77SDag-Erling Smørgrav 	 * This is the state that event is in or should sent to -- all
226b7579f77SDag-Erling Smørgrav 	 * requests should start with the INIT_REQUEST_STATE. All
227b7579f77SDag-Erling Smørgrav 	 * responses should start with QUERY_RESP_STATE. Subsequent
228b7579f77SDag-Erling Smørgrav 	 * processing of the event will change this state.
229b7579f77SDag-Erling Smørgrav 	 */
230b7579f77SDag-Erling Smørgrav 	enum iter_state state;
231b7579f77SDag-Erling Smørgrav 
232b7579f77SDag-Erling Smørgrav 	/**
233b7579f77SDag-Erling Smørgrav 	 * Final state for the iterator module.
234b7579f77SDag-Erling Smørgrav 	 * This is the state that responses should be routed to once the
235b7579f77SDag-Erling Smørgrav 	 * response is final. For externally initiated queries, this
236b7579f77SDag-Erling Smørgrav 	 * will be FINISHED_STATE, locally initiated queries will have
237b7579f77SDag-Erling Smørgrav 	 * different final states.
238b7579f77SDag-Erling Smørgrav 	 */
239b7579f77SDag-Erling Smørgrav 	enum iter_state final_state;
240b7579f77SDag-Erling Smørgrav 
241b7579f77SDag-Erling Smørgrav 	/**
242b7579f77SDag-Erling Smørgrav 	 * The depth of this query, this means the depth of recursion.
243b7579f77SDag-Erling Smørgrav 	 * This address is needed for another query, which is an address
244b7579f77SDag-Erling Smørgrav 	 * needed for another query, etc. Original client query has depth 0.
245b7579f77SDag-Erling Smørgrav 	 */
246b7579f77SDag-Erling Smørgrav 	int depth;
247b7579f77SDag-Erling Smørgrav 
248b7579f77SDag-Erling Smørgrav 	/**
249b7579f77SDag-Erling Smørgrav 	 * The response
250b7579f77SDag-Erling Smørgrav 	 */
251b7579f77SDag-Erling Smørgrav 	struct dns_msg* response;
252b7579f77SDag-Erling Smørgrav 
253b7579f77SDag-Erling Smørgrav 	/**
254b7579f77SDag-Erling Smørgrav 	 * This is a list of RRsets that must be prepended to the
255b7579f77SDag-Erling Smørgrav 	 * ANSWER section of a response before being sent upstream.
256b7579f77SDag-Erling Smørgrav 	 */
257b7579f77SDag-Erling Smørgrav 	struct iter_prep_list* an_prepend_list;
258b7579f77SDag-Erling Smørgrav 	/** Last element of the prepend list */
259b7579f77SDag-Erling Smørgrav 	struct iter_prep_list* an_prepend_last;
260b7579f77SDag-Erling Smørgrav 
261b7579f77SDag-Erling Smørgrav 	/**
262b7579f77SDag-Erling Smørgrav 	 * This is the list of RRsets that must be prepended to the
263b7579f77SDag-Erling Smørgrav 	 * AUTHORITY section of the response before being sent upstream.
264b7579f77SDag-Erling Smørgrav 	 */
265b7579f77SDag-Erling Smørgrav 	struct iter_prep_list* ns_prepend_list;
266b7579f77SDag-Erling Smørgrav 	/** Last element of the authority prepend list */
267b7579f77SDag-Erling Smørgrav 	struct iter_prep_list* ns_prepend_last;
268b7579f77SDag-Erling Smørgrav 
269b7579f77SDag-Erling Smørgrav 	/** query name used for chasing the results. Initially the same as
270b7579f77SDag-Erling Smørgrav 	 * the state qinfo, but after CNAMEs this will be different.
271b7579f77SDag-Erling Smørgrav 	 * The query info used to elicit the results needed. */
272b7579f77SDag-Erling Smørgrav 	struct query_info qchase;
273b7579f77SDag-Erling Smørgrav 	/** query flags to use when chasing the answer (i.e. RD flag) */
274b7579f77SDag-Erling Smørgrav 	uint16_t chase_flags;
275b7579f77SDag-Erling Smørgrav 	/** true if we set RD bit because of last resort recursion lame query*/
276b7579f77SDag-Erling Smørgrav 	int chase_to_rd;
277b7579f77SDag-Erling Smørgrav 
278b7579f77SDag-Erling Smørgrav 	/**
279b7579f77SDag-Erling Smørgrav 	 * This is the current delegation point for an in-progress query. This
280b7579f77SDag-Erling Smørgrav 	 * object retains state as to which delegation targets need to be
281b7579f77SDag-Erling Smørgrav 	 * (sub)queried for vs which ones have already been visited.
282b7579f77SDag-Erling Smørgrav 	 */
283b7579f77SDag-Erling Smørgrav 	struct delegpt* dp;
284b7579f77SDag-Erling Smørgrav 
285b7579f77SDag-Erling Smørgrav 	/** state for 0x20 fallback when capsfail happens, 0 not a fallback */
286b7579f77SDag-Erling Smørgrav 	int caps_fallback;
287b7579f77SDag-Erling Smørgrav 	/** state for capsfail: current server number to try */
288b7579f77SDag-Erling Smørgrav 	size_t caps_server;
289ff825849SDag-Erling Smørgrav 	/** state for capsfail: stored query for comparisons. Can be NULL if
290ff825849SDag-Erling Smørgrav 	 * no response had been seen prior to starting the fallback. */
291b7579f77SDag-Erling Smørgrav 	struct reply_info* caps_reply;
29209a3aaf3SDag-Erling Smørgrav 	struct dns_msg* caps_response;
293b7579f77SDag-Erling Smørgrav 
294b7579f77SDag-Erling Smørgrav 	/** Current delegation message - returned for non-RD queries */
295b7579f77SDag-Erling Smørgrav 	struct dns_msg* deleg_msg;
296b7579f77SDag-Erling Smørgrav 
297b7579f77SDag-Erling Smørgrav 	/** number of outstanding target sub queries */
298b7579f77SDag-Erling Smørgrav 	int num_target_queries;
299b7579f77SDag-Erling Smørgrav 
300b7579f77SDag-Erling Smørgrav 	/** outstanding direct queries */
301b7579f77SDag-Erling Smørgrav 	int num_current_queries;
302b7579f77SDag-Erling Smørgrav 
303b7579f77SDag-Erling Smørgrav 	/** the number of times this query has been restarted. */
304b7579f77SDag-Erling Smørgrav 	int query_restart_count;
305b7579f77SDag-Erling Smørgrav 
306b7579f77SDag-Erling Smørgrav 	/** the number of times this query as followed a referral. */
307b7579f77SDag-Erling Smørgrav 	int referral_count;
308b7579f77SDag-Erling Smørgrav 
309b7579f77SDag-Erling Smørgrav 	/** number of queries fired off */
310b7579f77SDag-Erling Smørgrav 	int sent_count;
311b7579f77SDag-Erling Smørgrav 
31252df462fSXin LI 	/** number of target queries spawned in [1], for this query and its
313091e9e46SCy Schubert 	 * subqueries, the malloced-array is shared, [0] refcount.
314091e9e46SCy Schubert 	 * in [2] the number of nxdomains is counted. */
31552df462fSXin LI 	int* target_count;
31652df462fSXin LI 
317091e9e46SCy Schubert 	/** number of target lookups per delegation point. Reset to 0 after
318091e9e46SCy Schubert 	 * receiving referral answer. Not shared with subqueries. */
319091e9e46SCy Schubert 	int dp_target_count;
320091e9e46SCy Schubert 
32109a3aaf3SDag-Erling Smørgrav 	/** if true, already tested for ratelimiting and passed the test */
32209a3aaf3SDag-Erling Smørgrav 	int ratelimit_ok;
32309a3aaf3SDag-Erling Smørgrav 
324b7579f77SDag-Erling Smørgrav 	/**
325b7579f77SDag-Erling Smørgrav 	 * The query must store NS records from referrals as parentside RRs
326b7579f77SDag-Erling Smørgrav 	 * Enabled once it hits resolution problems, to throttle retries.
327b7579f77SDag-Erling Smørgrav 	 * If enabled it is the pointer to the old delegation point with
328b7579f77SDag-Erling Smørgrav 	 * the old retry counts for bad-nameserver-addresses.
329b7579f77SDag-Erling Smørgrav 	 */
330b7579f77SDag-Erling Smørgrav 	struct delegpt* store_parent_NS;
331b7579f77SDag-Erling Smørgrav 
332b7579f77SDag-Erling Smørgrav 	/**
333b7579f77SDag-Erling Smørgrav 	 * The query is for parent-side glue(A or AAAA) for a nameserver.
334b7579f77SDag-Erling Smørgrav 	 * If the item is seen as glue in a referral, and pside_glue is NULL,
335b7579f77SDag-Erling Smørgrav 	 * then it is stored in pside_glue for later.
336b7579f77SDag-Erling Smørgrav 	 * If it was never seen, at the end, then a negative caching element
337b7579f77SDag-Erling Smørgrav 	 * must be created.
338b7579f77SDag-Erling Smørgrav 	 * The (data or negative) RR cache element then throttles retries.
339b7579f77SDag-Erling Smørgrav 	 */
340b7579f77SDag-Erling Smørgrav 	int query_for_pside_glue;
341b7579f77SDag-Erling Smørgrav 	/** the parent-side-glue element (NULL if none, its first match) */
342b7579f77SDag-Erling Smørgrav 	struct ub_packed_rrset_key* pside_glue;
343b7579f77SDag-Erling Smørgrav 
344b7579f77SDag-Erling Smørgrav 	/** If nonNULL we are walking upwards from DS query to find NS */
345b7579f77SDag-Erling Smørgrav 	uint8_t* dsns_point;
346b7579f77SDag-Erling Smørgrav 	/** length of the dname in dsns_point */
347b7579f77SDag-Erling Smørgrav 	size_t dsns_point_len;
348b7579f77SDag-Erling Smørgrav 
349b7579f77SDag-Erling Smørgrav 	/**
350b7579f77SDag-Erling Smørgrav 	 * expected dnssec information for this iteration step.
351b7579f77SDag-Erling Smørgrav 	 * If dnssec rrsigs are expected and not given, the server is marked
352b7579f77SDag-Erling Smørgrav 	 * lame (dnssec-lame).
353b7579f77SDag-Erling Smørgrav 	 */
354b7579f77SDag-Erling Smørgrav 	int dnssec_expected;
355b7579f77SDag-Erling Smørgrav 
356b7579f77SDag-Erling Smørgrav 	/**
357b7579f77SDag-Erling Smørgrav 	 * We are expecting dnssec information, but we also know the server
358b7579f77SDag-Erling Smørgrav 	 * is DNSSEC lame.  The response need not be marked dnssec-lame again.
359b7579f77SDag-Erling Smørgrav 	 */
360b7579f77SDag-Erling Smørgrav 	int dnssec_lame_query;
361b7579f77SDag-Erling Smørgrav 
362b7579f77SDag-Erling Smørgrav 	/**
363b7579f77SDag-Erling Smørgrav 	 * This is flag that, if true, means that this event is
364b7579f77SDag-Erling Smørgrav 	 * waiting for a stub priming query.
365b7579f77SDag-Erling Smørgrav 	 */
366b7579f77SDag-Erling Smørgrav 	int wait_priming_stub;
367b7579f77SDag-Erling Smørgrav 
368b7579f77SDag-Erling Smørgrav 	/**
369b7579f77SDag-Erling Smørgrav 	 * This is a flag that, if true, means that this query is
370b7579f77SDag-Erling Smørgrav 	 * for (re)fetching glue from a zone. Since the address should
371b7579f77SDag-Erling Smørgrav 	 * have been glue, query again to the servers that should have
372b7579f77SDag-Erling Smørgrav 	 * been returning it as glue.
373b7579f77SDag-Erling Smørgrav 	 * The delegation point must be set to the one that should *not*
374b7579f77SDag-Erling Smørgrav 	 * be used when creating the state. A higher one will be attempted.
375b7579f77SDag-Erling Smørgrav 	 */
376b7579f77SDag-Erling Smørgrav 	int refetch_glue;
377b7579f77SDag-Erling Smørgrav 
378b7579f77SDag-Erling Smørgrav 	/** list of pending queries to authoritative servers. */
379b7579f77SDag-Erling Smørgrav 	struct outbound_list outlist;
38005ab2901SDag-Erling Smørgrav 
381e2d15004SDag-Erling Smørgrav 	/** QNAME minimisation state, RFC7816 */
38205ab2901SDag-Erling Smørgrav 	enum minimisation_state minimisation_state;
38305ab2901SDag-Erling Smørgrav 
3844c75e3aaSDag-Erling Smørgrav 	/** State for capsfail: QNAME minimisation state for comparisons. */
3854c75e3aaSDag-Erling Smørgrav 	enum minimisation_state caps_minimisation_state;
3864c75e3aaSDag-Erling Smørgrav 
38705ab2901SDag-Erling Smørgrav 	/**
38805ab2901SDag-Erling Smørgrav 	 * The query info that is sent upstream. Will be a subset of qchase
38905ab2901SDag-Erling Smørgrav 	 * when qname minimisation is enabled.
39005ab2901SDag-Erling Smørgrav 	 */
39105ab2901SDag-Erling Smørgrav 	struct query_info qinfo_out;
392e2d15004SDag-Erling Smørgrav 
393e2d15004SDag-Erling Smørgrav 	/**
3948a384985SDag-Erling Smørgrav 	 * Count number of QNAME minimisation iterations. Used to limit number of
395e2d15004SDag-Erling Smørgrav 	 * outgoing queries when QNAME minimisation is enabled.
396e2d15004SDag-Erling Smørgrav 	 */
397e2d15004SDag-Erling Smørgrav 	int minimise_count;
398b5663de9SDag-Erling Smørgrav 
399b5663de9SDag-Erling Smørgrav 	/**
400b5663de9SDag-Erling Smørgrav 	 * Count number of time-outs. Used to prevent resolving failures when
40125039b37SCy Schubert 	 * the QNAME minimisation QTYPE is blocked. Used to determine if
40225039b37SCy Schubert 	 * capsforid fallback should be started.*/
40325039b37SCy Schubert 	int timeout_count;
40457bddd21SDag-Erling Smørgrav 
40557bddd21SDag-Erling Smørgrav 	/** True if the current response is from auth_zone */
40657bddd21SDag-Erling Smørgrav 	int auth_zone_response;
40757bddd21SDag-Erling Smørgrav 	/** True if the auth_zones should not be consulted for the query */
40857bddd21SDag-Erling Smørgrav 	int auth_zone_avoid;
409*5469a995SCy Schubert 	/** true if there have been scrubbing failures of reply packets */
410*5469a995SCy Schubert 	int scrub_failures;
411*5469a995SCy Schubert 	/** true if there have been parse failures of reply packets */
412*5469a995SCy Schubert 	int parse_failures;
413*5469a995SCy Schubert 	/** a failure printout address for last received answer */
414*5469a995SCy Schubert 	struct comm_reply* fail_reply;
415b7579f77SDag-Erling Smørgrav };
416b7579f77SDag-Erling Smørgrav 
417b7579f77SDag-Erling Smørgrav /**
418b7579f77SDag-Erling Smørgrav  * List of prepend items
419b7579f77SDag-Erling Smørgrav  */
420b7579f77SDag-Erling Smørgrav struct iter_prep_list {
421b7579f77SDag-Erling Smørgrav 	/** next in list */
422b7579f77SDag-Erling Smørgrav 	struct iter_prep_list* next;
423b7579f77SDag-Erling Smørgrav 	/** rrset */
424b7579f77SDag-Erling Smørgrav 	struct ub_packed_rrset_key* rrset;
425b7579f77SDag-Erling Smørgrav };
426b7579f77SDag-Erling Smørgrav 
427b7579f77SDag-Erling Smørgrav /**
428b7579f77SDag-Erling Smørgrav  * Get the iterator function block.
429b7579f77SDag-Erling Smørgrav  * @return: function block with function pointers to iterator methods.
430b7579f77SDag-Erling Smørgrav  */
431b7579f77SDag-Erling Smørgrav struct module_func_block* iter_get_funcblock(void);
432b7579f77SDag-Erling Smørgrav 
433b7579f77SDag-Erling Smørgrav /**
434b7579f77SDag-Erling Smørgrav  * Get iterator state as a string
435b7579f77SDag-Erling Smørgrav  * @param state: to convert
436b7579f77SDag-Erling Smørgrav  * @return constant string that is printable.
437b7579f77SDag-Erling Smørgrav  */
438b7579f77SDag-Erling Smørgrav const char* iter_state_to_string(enum iter_state state);
439b7579f77SDag-Erling Smørgrav 
440b7579f77SDag-Erling Smørgrav /**
441b7579f77SDag-Erling Smørgrav  * See if iterator state is a response state
442b7579f77SDag-Erling Smørgrav  * @param s: to inspect
443b7579f77SDag-Erling Smørgrav  * @return true if response state.
444b7579f77SDag-Erling Smørgrav  */
445b7579f77SDag-Erling Smørgrav int iter_state_is_responsestate(enum iter_state s);
446b7579f77SDag-Erling Smørgrav 
447b7579f77SDag-Erling Smørgrav /** iterator init */
448b7579f77SDag-Erling Smørgrav int iter_init(struct module_env* env, int id);
449b7579f77SDag-Erling Smørgrav 
450b7579f77SDag-Erling Smørgrav /** iterator deinit */
451b7579f77SDag-Erling Smørgrav void iter_deinit(struct module_env* env, int id);
452b7579f77SDag-Erling Smørgrav 
453b7579f77SDag-Erling Smørgrav /** iterator operate on a query */
454b7579f77SDag-Erling Smørgrav void iter_operate(struct module_qstate* qstate, enum module_ev event, int id,
455b7579f77SDag-Erling Smørgrav 	struct outbound_entry* outbound);
456b7579f77SDag-Erling Smørgrav 
457b7579f77SDag-Erling Smørgrav /**
4588a384985SDag-Erling Smørgrav  * Return priming query results to interested super querystates.
459b7579f77SDag-Erling Smørgrav  *
460b7579f77SDag-Erling Smørgrav  * Sets the delegation point and delegation message (not nonRD queries).
461b7579f77SDag-Erling Smørgrav  * This is a callback from walk_supers.
462b7579f77SDag-Erling Smørgrav  *
463b7579f77SDag-Erling Smørgrav  * @param qstate: query state that finished.
464b7579f77SDag-Erling Smørgrav  * @param id: module id.
465b7579f77SDag-Erling Smørgrav  * @param super: the qstate to inform.
466b7579f77SDag-Erling Smørgrav  */
467b7579f77SDag-Erling Smørgrav void iter_inform_super(struct module_qstate* qstate, int id,
468b7579f77SDag-Erling Smørgrav 	struct module_qstate* super);
469b7579f77SDag-Erling Smørgrav 
470b7579f77SDag-Erling Smørgrav /** iterator cleanup query state */
471b7579f77SDag-Erling Smørgrav void iter_clear(struct module_qstate* qstate, int id);
472b7579f77SDag-Erling Smørgrav 
473b7579f77SDag-Erling Smørgrav /** iterator alloc size routine */
474b7579f77SDag-Erling Smørgrav size_t iter_get_mem(struct module_env* env, int id);
475b7579f77SDag-Erling Smørgrav 
476b7579f77SDag-Erling Smørgrav #endif /* ITERATOR_ITERATOR_H */
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