xref: /netbsd-src/external/mpl/dhcp/bind/dist/lib/dns/include/dns/request.h (revision 4afad4b7fa6d4a0d3dedf41d1587a7250710ae54)
1 /*	$NetBSD: request.h,v 1.1 2024/02/18 20:57:38 christos Exp $	*/
2 
3 /*
4  * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
5  *
6  * SPDX-License-Identifier: MPL-2.0
7  *
8  * This Source Code Form is subject to the terms of the Mozilla Public
9  * License, v. 2.0. If a copy of the MPL was not distributed with this
10  * file, you can obtain one at https://mozilla.org/MPL/2.0/.
11  *
12  * See the COPYRIGHT file distributed with this work for additional
13  * information regarding copyright ownership.
14  */
15 
16 #ifndef DNS_REQUEST_H
17 #define DNS_REQUEST_H 1
18 
19 /*****
20 ***** Module Info
21 *****/
22 
23 /*! \file dns/request.h
24  *
25  * \brief
26  * The request module provides simple request/response services useful for
27  * sending SOA queries, DNS Notify messages, and dynamic update requests.
28  *
29  * MP:
30  *\li	The module ensures appropriate synchronization of data structures it
31  *	creates and manipulates.
32  *
33  * Resources:
34  *\li	TBS
35  *
36  * Security:
37  *\li	No anticipated impact.
38  */
39 
40 #include <stdbool.h>
41 
42 #include <isc/event.h>
43 #include <isc/lang.h>
44 
45 #include <dns/types.h>
46 
47 #define DNS_REQUESTOPT_TCP     0x00000001U
48 #define DNS_REQUESTOPT_CASE    0x00000002U
49 #define DNS_REQUESTOPT_FIXEDID 0x00000004U
50 #define DNS_REQUESTOPT_SHARE   0x00000008U
51 
52 typedef struct dns_requestevent {
53 	ISC_EVENT_COMMON(struct dns_requestevent);
54 	isc_result_t   result;
55 	dns_request_t *request;
56 } dns_requestevent_t;
57 
58 ISC_LANG_BEGINDECLS
59 
60 isc_result_t
61 dns_requestmgr_create(isc_mem_t *mctx, isc_timermgr_t *timermgr,
62 		      isc_socketmgr_t *socketmgr, isc_taskmgr_t *taskmgr,
63 		      dns_dispatchmgr_t *dispatchmgr,
64 		      dns_dispatch_t *dispatchv4, dns_dispatch_t *dispatchv6,
65 		      dns_requestmgr_t **requestmgrp);
66 /*%<
67  * Create a request manager.
68  *
69  * Requires:
70  *
71  *\li	'mctx' is a valid memory context.
72  *
73  *\li	'timermgr' is a valid timer manager.
74  *
75  *\li	'socketmgr' is a valid socket manager.
76  *
77  *\li	'taskmgr' is a valid task manager.
78  *
79  *\li	'dispatchv4' is a valid dispatcher with an IPv4 UDP socket, or is NULL.
80  *
81  *\li	'dispatchv6' is a valid dispatcher with an IPv6 UDP socket, or is NULL.
82  *
83  *\li	requestmgrp != NULL && *requestmgrp == NULL
84  *
85  * Ensures:
86  *
87  *\li	On success, *requestmgrp is a valid request manager.
88  *
89  * Returns:
90  *
91  *\li	ISC_R_SUCCESS
92  *
93  *\li	Any other result indicates failure.
94  */
95 
96 void
97 dns_requestmgr_whenshutdown(dns_requestmgr_t *requestmgr, isc_task_t *task,
98 			    isc_event_t **eventp);
99 /*%<
100  * Send '*eventp' to 'task' when 'requestmgr' has completed shutdown.
101  *
102  * Notes:
103  *
104  *\li	It is not safe to detach the last reference to 'requestmgr' until
105  *	shutdown is complete.
106  *
107  * Requires:
108  *
109  *\li	'requestmgr' is a valid request manager.
110  *
111  *\li	'task' is a valid task.
112  *
113  *\li	*eventp is a valid event.
114  *
115  * Ensures:
116  *
117  *\li	*eventp == NULL.
118  */
119 
120 void
121 dns_requestmgr_shutdown(dns_requestmgr_t *requestmgr);
122 /*%<
123  * Start the shutdown process for 'requestmgr'.
124  *
125  * Notes:
126  *
127  *\li	This call has no effect if the request manager is already shutting
128  *	down.
129  *
130  * Requires:
131  *
132  *\li	'requestmgr' is a valid requestmgr.
133  */
134 
135 void
136 dns_requestmgr_attach(dns_requestmgr_t *source, dns_requestmgr_t **targetp);
137 /*%<
138  *	Attach to the request manager.  dns_requestmgr_shutdown() must not
139  *	have been called on 'source' prior to calling dns_requestmgr_attach().
140  *
141  * Requires:
142  *
143  *\li	'source' is a valid requestmgr.
144  *
145  *\li	'targetp' to be non NULL and '*targetp' to be NULL.
146  */
147 
148 void
149 dns_requestmgr_detach(dns_requestmgr_t **requestmgrp);
150 /*%<
151  *	Detach from the given requestmgr.  If this is the final detach
152  *	requestmgr will be destroyed.  dns_requestmgr_shutdown() must
153  *	be called before the final detach.
154  *
155  * Requires:
156  *
157  *\li	'*requestmgrp' is a valid requestmgr.
158  *
159  * Ensures:
160  *\li	'*requestmgrp' is NULL.
161  */
162 
163 isc_result_t
164 dns_request_create(dns_requestmgr_t *requestmgr, dns_message_t *message,
165 		   const isc_sockaddr_t *address, unsigned int options,
166 		   dns_tsigkey_t *key, unsigned int timeout, isc_task_t *task,
167 		   isc_taskaction_t action, void *arg,
168 		   dns_request_t **requestp);
169 /*%<
170  * Create and send a request.
171  *
172  * Notes:
173  *
174  *\li	'message' will be rendered and sent to 'address'.  If the
175  *	#DNS_REQUESTOPT_TCP option is set, TCP will be used,
176  *	#DNS_REQUESTOPT_SHARE option is set too, connecting TCP
177  *	(vs. connected) will be shared too.  The request
178  *	will timeout after 'timeout' seconds.
179  *
180  *\li	If the #DNS_REQUESTOPT_CASE option is set, use case sensitive
181  *	compression.
182  *
183  *\li	When the request completes, successfully, due to a timeout, or
184  *	because it was canceled, a completion event will be sent to 'task'.
185  *
186  * Requires:
187  *
188  *\li	'message' is a valid DNS message.
189  *
190  *\li	'address' is a valid sockaddr.
191  *
192  *\li	'timeout' > 0
193  *
194  *\li	'task' is a valid task.
195  *
196  *\li	requestp != NULL && *requestp == NULL
197  */
198 
199 isc_result_t
200 dns_request_createvia(dns_requestmgr_t *requestmgr, dns_message_t *message,
201 		      const isc_sockaddr_t *srcaddr,
202 		      const isc_sockaddr_t *destaddr, isc_dscp_t dscp,
203 		      unsigned int options, dns_tsigkey_t *key,
204 		      unsigned int timeout, unsigned int udptimeout,
205 		      unsigned int udpretries, isc_task_t *task,
206 		      isc_taskaction_t action, void *arg,
207 		      dns_request_t **requestp);
208 /*%<
209  * Create and send a request.
210  *
211  * Notes:
212  *
213  *\li	'message' will be rendered and sent to 'address'.  If the
214  *	#DNS_REQUESTOPT_TCP option is set, TCP will be used,
215  *	#DNS_REQUESTOPT_SHARE option is set too, connecting TCP
216  *	(vs. connected) will be shared too.  The request
217  *	will timeout after 'timeout' seconds.  UDP requests will be resent
218  *	at 'udptimeout' intervals if non-zero or 'udpretries' is non-zero.
219  *
220  *\li	If the #DNS_REQUESTOPT_CASE option is set, use case sensitive
221  *	compression.
222  *
223  *\li	When the request completes, successfully, due to a timeout, or
224  *	because it was canceled, a completion event will be sent to 'task'.
225  *
226  * Requires:
227  *
228  *\li	'message' is a valid DNS message.
229  *
230  *\li	'dstaddr' is a valid sockaddr.
231  *
232  *\li	'srcaddr' is a valid sockaddr or NULL.
233  *
234  *\li	'srcaddr' and 'dstaddr' are the same protocol family.
235  *
236  *\li	'timeout' > 0
237  *
238  *\li	'task' is a valid task.
239  *
240  *\li	requestp != NULL && *requestp == NULL
241  */
242 
243 isc_result_t
244 dns_request_createraw(dns_requestmgr_t *requestmgr, isc_buffer_t *msgbuf,
245 		      const isc_sockaddr_t *srcaddr,
246 		      const isc_sockaddr_t *destaddr, isc_dscp_t dscp,
247 		      unsigned int options, unsigned int timeout,
248 		      unsigned int udptimeout, unsigned int udpretries,
249 		      isc_task_t *task, isc_taskaction_t action, void *arg,
250 		      dns_request_t **requestp);
251 /*!<
252  * \brief Create and send a request.
253  *
254  * Notes:
255  *
256  *\li	'msgbuf' will be sent to 'destaddr' after setting the id.  If the
257  *	#DNS_REQUESTOPT_TCP option is set, TCP will be used,
258  *	#DNS_REQUESTOPT_SHARE option is set too, connecting TCP
259  *	(vs. connected) will be shared too.  The request
260  *	will timeout after 'timeout' seconds.   UDP requests will be resent
261  *	at 'udptimeout' intervals if non-zero or if 'udpretries' is not zero.
262  *
263  *\li	When the request completes, successfully, due to a timeout, or
264  *	because it was canceled, a completion event will be sent to 'task'.
265  *
266  * Requires:
267  *
268  *\li	'msgbuf' is a valid DNS message in compressed wire format.
269  *
270  *\li	'destaddr' is a valid sockaddr.
271  *
272  *\li	'srcaddr' is a valid sockaddr or NULL.
273  *
274  *\li	'srcaddr' and 'dstaddr' are the same protocol family.
275  *
276  *\li	'timeout' > 0
277  *
278  *\li	'task' is a valid task.
279  *
280  *\li	requestp != NULL && *requestp == NULL
281  */
282 
283 void
284 dns_request_cancel(dns_request_t *request);
285 /*%<
286  * Cancel 'request'.
287  *
288  * Requires:
289  *
290  *\li	'request' is a valid request.
291  *
292  * Ensures:
293  *
294  *\li	If the completion event for 'request' has not yet been sent, it
295  *	will be sent, and the result code will be ISC_R_CANCELED.
296  */
297 
298 isc_result_t
299 dns_request_getresponse(dns_request_t *request, dns_message_t *message,
300 			unsigned int options);
301 /*%<
302  * Get the response to 'request' by filling in 'message'.
303  *
304  * 'options' is passed to dns_message_parse().  See dns_message_parse()
305  * for more details.
306  *
307  * Requires:
308  *
309  *\li	'request' is a valid request for which the caller has received the
310  *	completion event.
311  *
312  *\li	The result code of the completion event was #ISC_R_SUCCESS.
313  *
314  * Returns:
315  *
316  *\li	ISC_R_SUCCESS
317  *
318  *\li	Any result that dns_message_parse() can return.
319  */
320 isc_buffer_t *
321 dns_request_getanswer(dns_request_t *request);
322 /*
323  * Get the response to 'request' as a buffer.
324  *
325  * Requires:
326  *
327  *\li	'request' is a valid request for which the caller has received the
328  *	completion event.
329  *
330  * Returns:
331  *
332  *\li	a pointer to the answer buffer.
333  */
334 
335 bool
336 dns_request_usedtcp(dns_request_t *request);
337 /*%<
338  * Return whether this query used TCP or not.  Setting #DNS_REQUESTOPT_TCP
339  * in the call to dns_request_create() will cause the function to return
340  * #true, otherwise the result is based on the query message size.
341  *
342  * Requires:
343  *\li	'request' is a valid request.
344  *
345  * Returns:
346  *\li	true	if TCP was used.
347  *\li	false	if UDP was used.
348  */
349 
350 void
351 dns_request_destroy(dns_request_t **requestp);
352 /*%<
353  * Destroy 'request'.
354  *
355  * Requires:
356  *
357  *\li	'request' is a valid request for which the caller has received the
358  *	completion event.
359  *
360  * Ensures:
361  *
362  *\li	*requestp == NULL
363  */
364 
365 ISC_LANG_ENDDECLS
366 
367 #endif /* DNS_REQUEST_H */
368