1/*	$NetBSD: lwdgnba.c,v 1.2.6.1 2012/06/05 21:15:22 bouyer Exp $	*/
2
3/*
4 * Copyright (C) 2004, 2005, 2007, 2008  Internet Systems Consortium, Inc. ("ISC")
5 * Copyright (C) 2000-2002  Internet Software Consortium.
6 *
7 * Permission to use, copy, modify, and/or distribute this software for any
8 * purpose with or without fee is hereby granted, provided that the above
9 * copyright notice and this permission notice appear in all copies.
10 *
11 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
12 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
13 * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
14 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
15 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
16 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
17 * PERFORMANCE OF THIS SOFTWARE.
18 */
19
20/* Id: lwdgnba.c,v 1.22 2008/01/14 23:46:56 tbox Exp  */
21
22/*! \file */
23
24#include <config.h>
25
26#include <isc/socket.h>
27#include <isc/string.h>		/* Required for HP/UX (and others?) */
28#include <isc/util.h>
29
30#include <dns/adb.h>
31#include <dns/byaddr.h>
32#include <dns/result.h>
33
34#include <named/types.h>
35#include <named/lwdclient.h>
36
37static void start_byaddr(ns_lwdclient_t *);
38
39static void
40byaddr_done(isc_task_t *task, isc_event_t *event) {
41	ns_lwdclient_t *client;
42	ns_lwdclientmgr_t *cm;
43	dns_byaddrevent_t *bevent;
44	int lwres;
45	lwres_buffer_t lwb;
46	dns_name_t *name;
47	isc_result_t result;
48	lwres_result_t lwresult;
49	isc_region_t r;
50	isc_buffer_t b;
51	lwres_gnbaresponse_t *gnba;
52	isc_uint16_t naliases;
53
54	UNUSED(task);
55
56	lwb.base = NULL;
57	client = event->ev_arg;
58	cm = client->clientmgr;
59	INSIST(client->byaddr == (dns_byaddr_t *)event->ev_sender);
60
61	bevent = (dns_byaddrevent_t *)event;
62	gnba = &client->gnba;
63
64	ns_lwdclient_log(50, "byaddr event result = %s",
65			 isc_result_totext(bevent->result));
66
67	result = bevent->result;
68	if (result != ISC_R_SUCCESS) {
69		dns_byaddr_destroy(&client->byaddr);
70		isc_event_free(&event);
71		bevent = NULL;
72
73		if (client->na.family != AF_INET6 ||
74		    (client->options & DNS_BYADDROPT_IPV6INT) != 0) {
75			if (result == DNS_R_NCACHENXDOMAIN ||
76			    result == DNS_R_NCACHENXRRSET ||
77			    result == DNS_R_NXDOMAIN ||
78			    result == DNS_R_NXRRSET)
79				lwresult = LWRES_R_NOTFOUND;
80			else
81				lwresult = LWRES_R_FAILURE;
82			ns_lwdclient_errorpktsend(client, lwresult);
83			return;
84		}
85
86		/*
87		 * Fall back to ip6.int reverse if the default ip6.arpa
88		 * fails.
89		 */
90		client->options |= DNS_BYADDROPT_IPV6INT;
91
92		start_byaddr(client);
93		return;
94	}
95
96	for (name = ISC_LIST_HEAD(bevent->names);
97	     name != NULL;
98	     name = ISC_LIST_NEXT(name, link))
99	{
100		b = client->recv_buffer;
101
102		result = dns_name_totext(name, ISC_TRUE, &client->recv_buffer);
103		if (result != ISC_R_SUCCESS)
104			goto out;
105		ns_lwdclient_log(50, "found name '%.*s'",
106				 (int)(client->recv_buffer.used - b.used),
107				 (char *)(b.base) + b.used);
108		if (gnba->realname == NULL) {
109			gnba->realname = (char *)(b.base) + b.used;
110			gnba->realnamelen = client->recv_buffer.used - b.used;
111		} else {
112			naliases = gnba->naliases;
113			if (naliases >= LWRES_MAX_ALIASES)
114				break;
115			gnba->aliases[naliases] = (char *)(b.base) + b.used;
116			gnba->aliaslen[naliases] =
117				client->recv_buffer.used - b.used;
118			gnba->naliases++;
119		}
120	}
121
122	dns_byaddr_destroy(&client->byaddr);
123	isc_event_free(&event);
124
125	/*
126	 * Render the packet.
127	 */
128	client->pkt.recvlength = LWRES_RECVLENGTH;
129	client->pkt.authtype = 0; /* XXXMLG */
130	client->pkt.authlength = 0;
131	client->pkt.result = LWRES_R_SUCCESS;
132
133	lwres = lwres_gnbaresponse_render(cm->lwctx,
134					  gnba, &client->pkt, &lwb);
135	if (lwres != LWRES_R_SUCCESS)
136		goto out;
137
138	r.base = lwb.base;
139	r.length = lwb.used;
140	client->sendbuf = r.base;
141	client->sendlength = r.length;
142	result = ns_lwdclient_sendreply(client, &r);
143	if (result != ISC_R_SUCCESS)
144		goto out;
145
146	NS_LWDCLIENT_SETSEND(client);
147
148	return;
149
150 out:
151	if (client->byaddr != NULL)
152		dns_byaddr_destroy(&client->byaddr);
153	if (lwb.base != NULL)
154		lwres_context_freemem(cm->lwctx,
155				      lwb.base, lwb.length);
156
157	if (event != NULL)
158		isc_event_free(&event);
159}
160
161static void
162start_byaddr(ns_lwdclient_t *client) {
163	isc_result_t result;
164	ns_lwdclientmgr_t *cm;
165
166	cm = client->clientmgr;
167
168	INSIST(client->byaddr == NULL);
169
170	result = dns_byaddr_create(cm->mctx, &client->na, cm->view,
171				   client->options, cm->task, byaddr_done,
172				   client, &client->byaddr);
173	if (result != ISC_R_SUCCESS) {
174		ns_lwdclient_errorpktsend(client, LWRES_R_FAILURE);
175		return;
176	}
177}
178
179static void
180init_gnba(ns_lwdclient_t *client) {
181	int i;
182
183	/*
184	 * Initialize the real name and alias arrays in the reply we're
185	 * going to build up.
186	 */
187	for (i = 0; i < LWRES_MAX_ALIASES; i++) {
188		client->aliases[i] = NULL;
189		client->aliaslen[i] = 0;
190	}
191	for (i = 0; i < LWRES_MAX_ADDRS; i++) {
192		client->addrs[i].family = 0;
193		client->addrs[i].length = 0;
194		memset(client->addrs[i].address, 0, LWRES_ADDR_MAXLEN);
195		LWRES_LINK_INIT(&client->addrs[i], link);
196	}
197
198	client->gnba.naliases = 0;
199	client->gnba.realname = NULL;
200	client->gnba.aliases = client->aliases;
201	client->gnba.realnamelen = 0;
202	client->gnba.aliaslen = client->aliaslen;
203	client->gnba.base = NULL;
204	client->gnba.baselen = 0;
205	isc_buffer_init(&client->recv_buffer, client->buffer, LWRES_RECVLENGTH);
206}
207
208void
209ns_lwdclient_processgnba(ns_lwdclient_t *client, lwres_buffer_t *b) {
210	lwres_gnbarequest_t *req;
211	isc_result_t result;
212	isc_sockaddr_t sa;
213	ns_lwdclientmgr_t *cm;
214
215	REQUIRE(NS_LWDCLIENT_ISRECVDONE(client));
216	INSIST(client->byaddr == NULL);
217
218	cm = client->clientmgr;
219	req = NULL;
220
221	result = lwres_gnbarequest_parse(cm->lwctx,
222					 b, &client->pkt, &req);
223	if (result != LWRES_R_SUCCESS)
224		goto out;
225
226	client->options = 0;
227	if (req->addr.family == LWRES_ADDRTYPE_V4) {
228		client->na.family = AF_INET;
229		if (req->addr.length != 4)
230			goto out;
231		memcpy(&client->na.type.in, req->addr.address, 4);
232	} else if (req->addr.family == LWRES_ADDRTYPE_V6) {
233		client->na.family = AF_INET6;
234		if (req->addr.length != 16)
235			goto out;
236		memcpy(&client->na.type.in6, req->addr.address, 16);
237	} else {
238		goto out;
239	}
240	isc_sockaddr_fromnetaddr(&sa, &client->na, 53);
241
242	ns_lwdclient_log(50, "client %p looking for addrtype %08x",
243			 client, req->addr.family);
244
245	/*
246	 * We no longer need to keep this around.
247	 */
248	lwres_gnbarequest_free(cm->lwctx, &req);
249
250	/*
251	 * Initialize the real name and alias arrays in the reply we're
252	 * going to build up.
253	 */
254	init_gnba(client);
255	client->options = 0;
256
257	/*
258	 * Start the find.
259	 */
260	start_byaddr(client);
261
262	return;
263
264	/*
265	 * We're screwed.  Return an error packet to our caller.
266	 */
267 out:
268	if (req != NULL)
269		lwres_gnbarequest_free(cm->lwctx, &req);
270
271	ns_lwdclient_errorpktsend(client, LWRES_R_FAILURE);
272}
273