/contrib/bind9/bin/named/include/named/lwdclient.h

  1/*
  2 * Copyright (C) 2004, 2005, 2007, 2009  Internet Systems Consortium, Inc. ("ISC")
  3 * Copyright (C) 2000, 2001  Internet Software Consortium.
  4 *
  5 * Permission to use, copy, modify, and/or distribute this software for any
  6 * purpose with or without fee is hereby granted, provided that the above
  7 * copyright notice and this permission notice appear in all copies.
  8 *
  9 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
 10 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
 11 * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
 12 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
 13 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
 14 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 15 * PERFORMANCE OF THIS SOFTWARE.
 16 */
 17
 18/* $Id: lwdclient.h,v 1.20 2009/01/17 23:47:42 tbox Exp $ */
 19
 20#ifndef NAMED_LWDCLIENT_H
 21#define NAMED_LWDCLIENT_H 1
 22
 23/*! \file */
 24
 25#include <isc/event.h>
 26#include <isc/eventclass.h>
 27#include <isc/netaddr.h>
 28#include <isc/sockaddr.h>
 29#include <isc/types.h>
 30
 31#include <dns/fixedname.h>
 32#include <dns/types.h>
 33
 34#include <lwres/lwres.h>
 35
 36#include <named/lwsearch.h>
 37
 38#define LWRD_EVENTCLASS		ISC_EVENTCLASS(4242)
 39
 40#define LWRD_SHUTDOWN		(LWRD_EVENTCLASS + 0x0001)
 41
 42/*% Lightweight Resolver Daemon Client */
 43struct ns_lwdclient {
 44	isc_sockaddr_t		address;	/*%< where to reply */
 45	struct in6_pktinfo	pktinfo;
 46	isc_boolean_t		pktinfo_valid;
 47	ns_lwdclientmgr_t	*clientmgr;	/*%< our parent */
 48	ISC_LINK(ns_lwdclient_t) link;
 49	unsigned int		state;
 50	void			*arg;		/*%< packet processing state */
 51
 52	/*
 53	 * Received data info.
 54	 */
 55	unsigned char		buffer[LWRES_RECVLENGTH]; /*%< receive buffer */
 56	isc_uint32_t		recvlength;	/*%< length recv'd */
 57	lwres_lwpacket_t	pkt;
 58
 59	/*%
 60	 * Send data state.  If sendbuf != buffer (that is, the send buffer
 61	 * isn't our receive buffer) it will be freed to the lwres_context_t.
 62	 */
 63	unsigned char	       *sendbuf;
 64	isc_uint32_t		sendlength;
 65	isc_buffer_t		recv_buffer;
 66
 67	/*%
 68	 * gabn (get address by name) state info.
 69	 */
 70	dns_adbfind_t		*find;
 71	dns_adbfind_t		*v4find;
 72	dns_adbfind_t		*v6find;
 73	unsigned int		find_wanted;	/*%< Addresses we want */
 74	dns_fixedname_t		query_name;
 75	dns_fixedname_t		target_name;
 76	ns_lwsearchctx_t	searchctx;
 77	lwres_gabnresponse_t	gabn;
 78
 79	/*%
 80	 * gnba (get name by address) state info.
 81	 */
 82	lwres_gnbaresponse_t	gnba;
 83	dns_byaddr_t	       *byaddr;
 84	unsigned int		options;
 85	isc_netaddr_t		na;
 86
 87	/*%
 88	 * grbn (get rrset by name) state info.
 89	 *
 90	 * Note: this also uses target_name and searchctx.
 91	 */
 92	lwres_grbnresponse_t	grbn;
 93	dns_lookup_t	       *lookup;
 94	dns_rdatatype_t		rdtype;
 95
 96	/*%
 97	 * Alias and address info.  This is copied up to the gabn/gnba
 98	 * structures eventually.
 99	 *
100	 * XXXMLG We can keep all of this in a client since we only service
101	 * three packet types right now.  If we started handling more,
102	 * we'd need to use "arg" above and allocate/destroy things.
103	 */
104	char		       *aliases[LWRES_MAX_ALIASES];
105	isc_uint16_t		aliaslen[LWRES_MAX_ALIASES];
106	lwres_addr_t		addrs[LWRES_MAX_ADDRS];
107};
108
109/*%
110 * Client states.
111 *
112 * _IDLE	The client is not doing anything at all.
113 *
114 * _RECV	The client is waiting for data after issuing a socket recv().
115 *
116 * _RECVDONE	Data has been received, and is being processed.
117 *
118 * _FINDWAIT	An adb (or other) request was made that cannot be satisfied
119 *		immediately.  An event will wake the client up.
120 *
121 * _SEND	All data for a response has completed, and a reply was
122 *		sent via a socket send() call.
123 *
124 * Badly formatted state table:
125 *
126 *	IDLE -> RECV when client has a recv() queued.
127 *
128 *	RECV -> RECVDONE when recvdone event received.
129 *
130 *	RECVDONE -> SEND if the data for a reply is at hand.
131 *	RECVDONE -> FINDWAIT if more searching is needed, and events will
132 *		eventually wake us up again.
133 *
134 *	FINDWAIT -> SEND when enough data was received to reply.
135 *
136 *	SEND -> IDLE when a senddone event was received.
137 *
138 *	At any time -> IDLE on error.  Sometimes this will be -> SEND
139 *	instead, if enough data is on hand to reply with a meaningful
140 *	error.
141 *
142 *	Packets which are badly formatted may or may not get error returns.
143 */
144#define NS_LWDCLIENT_STATEIDLE		1
145#define NS_LWDCLIENT_STATERECV		2
146#define NS_LWDCLIENT_STATERECVDONE	3
147#define NS_LWDCLIENT_STATEFINDWAIT	4
148#define NS_LWDCLIENT_STATESEND		5
149#define NS_LWDCLIENT_STATESENDDONE	6
150
151#define NS_LWDCLIENT_ISIDLE(c)		\
152			((c)->state == NS_LWDCLIENT_STATEIDLE)
153#define NS_LWDCLIENT_ISRECV(c)		\
154			((c)->state == NS_LWDCLIENT_STATERECV)
155#define NS_LWDCLIENT_ISRECVDONE(c)	\
156			((c)->state == NS_LWDCLIENT_STATERECVDONE)
157#define NS_LWDCLIENT_ISFINDWAIT(c)	\
158			((c)->state == NS_LWDCLIENT_STATEFINDWAIT)
159#define NS_LWDCLIENT_ISSEND(c)		\
160			((c)->state == NS_LWDCLIENT_STATESEND)
161
162/*%
163 * Overall magic test that means we're not idle.
164 */
165#define NS_LWDCLIENT_ISRUNNING(c)	(!NS_LWDCLIENT_ISIDLE(c))
166
167#define NS_LWDCLIENT_SETIDLE(c)		\
168			((c)->state = NS_LWDCLIENT_STATEIDLE)
169#define NS_LWDCLIENT_SETRECV(c)		\
170			((c)->state = NS_LWDCLIENT_STATERECV)
171#define NS_LWDCLIENT_SETRECVDONE(c)	\
172			((c)->state = NS_LWDCLIENT_STATERECVDONE)
173#define NS_LWDCLIENT_SETFINDWAIT(c)	\
174			((c)->state = NS_LWDCLIENT_STATEFINDWAIT)
175#define NS_LWDCLIENT_SETSEND(c)		\
176			((c)->state = NS_LWDCLIENT_STATESEND)
177#define NS_LWDCLIENT_SETSENDDONE(c)	\
178			((c)->state = NS_LWDCLIENT_STATESENDDONE)
179
180/*% lightweight daemon client manager */
181struct ns_lwdclientmgr {
182	ns_lwreslistener_t     *listener;
183	isc_mem_t	       *mctx;
184	isc_socket_t	       *sock;		/*%< socket to use */
185	dns_view_t	       *view;
186	lwres_context_t	       *lwctx;		/*%< lightweight proto context */
187	isc_task_t	       *task;		/*%< owning task */
188	unsigned int		flags;
189	ISC_LINK(ns_lwdclientmgr_t)	link;
190	ISC_LIST(ns_lwdclient_t)	idle;		/*%< idle client slots */
191	ISC_LIST(ns_lwdclient_t)	running;	/*%< running clients */
192};
193
194#define NS_LWDCLIENTMGR_FLAGRECVPENDING		0x00000001
195#define NS_LWDCLIENTMGR_FLAGSHUTTINGDOWN	0x00000002
196
197isc_result_t
198ns_lwdclientmgr_create(ns_lwreslistener_t *, unsigned int, isc_taskmgr_t *);
199
200void
201ns_lwdclient_initialize(ns_lwdclient_t *, ns_lwdclientmgr_t *);
202
203isc_result_t
204ns_lwdclient_startrecv(ns_lwdclientmgr_t *);
205
206void
207ns_lwdclient_stateidle(ns_lwdclient_t *);
208
209void
210ns_lwdclient_recv(isc_task_t *, isc_event_t *);
211
212void
213ns_lwdclient_shutdown(isc_task_t *, isc_event_t *);
214
215void
216ns_lwdclient_send(isc_task_t *, isc_event_t *);
217
218isc_result_t
219ns_lwdclient_sendreply(ns_lwdclient_t *client, isc_region_t *r);
220
221/*
222 * Processing functions of various types.
223 */
224void ns_lwdclient_processgabn(ns_lwdclient_t *, lwres_buffer_t *);
225void ns_lwdclient_processgnba(ns_lwdclient_t *, lwres_buffer_t *);
226void ns_lwdclient_processgrbn(ns_lwdclient_t *, lwres_buffer_t *);
227void ns_lwdclient_processnoop(ns_lwdclient_t *, lwres_buffer_t *);
228
229void ns_lwdclient_errorpktsend(ns_lwdclient_t *, isc_uint32_t);
230
231void ns_lwdclient_log(int level, const char *format, ...)
232     ISC_FORMAT_PRINTF(2, 3);
233
234#endif /* NAMED_LWDCLIENT_H */