1/*
2 * Copyright (C) 2004, 2005, 2007, 2008, 2014  Internet Systems Consortium, Inc. ("ISC")
3 * Copyright (C) 2000-2002  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: lwdgnba.c,v 1.22 2008/01/14 23:46:56 tbox Exp $ */
19
20/*! \file */
21
22#include <config.h>
23
24#include <isc/socket.h>
25#include <isc/string.h>		/* Required for HP/UX (and others?) */
26#include <isc/util.h>
27
28#include <dns/adb.h>
29#include <dns/byaddr.h>
30#include <dns/result.h>
31
32#include <named/types.h>
33#include <named/lwdclient.h>
34
35static void start_byaddr(ns_lwdclient_t *);
36
37static void
38byaddr_done(isc_task_t *task, isc_event_t *event) {
39	ns_lwdclient_t *client;
40	ns_lwdclientmgr_t *cm;
41	dns_byaddrevent_t *bevent;
42	int lwres;
43	lwres_buffer_t lwb;
44	dns_name_t *name;
45	isc_result_t result;
46	lwres_result_t lwresult;
47	isc_region_t r;
48	isc_buffer_t b;
49	lwres_gnbaresponse_t *gnba;
50	isc_uint16_t naliases;
51
52	UNUSED(task);
53
54	lwb.base = NULL;
55	client = event->ev_arg;
56	cm = client->clientmgr;
57	INSIST(client->byaddr == (dns_byaddr_t *)event->ev_sender);
58
59	bevent = (dns_byaddrevent_t *)event;
60	gnba = &client->gnba;
61
62	ns_lwdclient_log(50, "byaddr event result = %s",
63			 isc_result_totext(bevent->result));
64
65	result = bevent->result;
66	if (result != ISC_R_SUCCESS) {
67		dns_byaddr_destroy(&client->byaddr);
68		isc_event_free(&event);
69		bevent = NULL;
70
71		if (client->na.family != AF_INET6 ||
72		    (client->options & DNS_BYADDROPT_IPV6INT) != 0) {
73			if (result == DNS_R_NCACHENXDOMAIN ||
74			    result == DNS_R_NCACHENXRRSET ||
75			    result == DNS_R_NXDOMAIN ||
76			    result == DNS_R_NXRRSET)
77				lwresult = LWRES_R_NOTFOUND;
78			else
79				lwresult = LWRES_R_FAILURE;
80			ns_lwdclient_errorpktsend(client, lwresult);
81			return;
82		}
83
84		/*
85		 * Fall back to ip6.int reverse if the default ip6.arpa
86		 * fails.
87		 */
88		client->options |= DNS_BYADDROPT_IPV6INT;
89
90		start_byaddr(client);
91		return;
92	}
93
94	for (name = ISC_LIST_HEAD(bevent->names);
95	     name != NULL;
96	     name = ISC_LIST_NEXT(name, link))
97	{
98		b = client->recv_buffer;
99
100		result = dns_name_totext(name, ISC_TRUE, &client->recv_buffer);
101		if (result != ISC_R_SUCCESS)
102			goto out;
103		ns_lwdclient_log(50, "found name '%.*s'",
104				 (int)(client->recv_buffer.used - b.used),
105				 (char *)(b.base) + b.used);
106		if (gnba->realname == NULL) {
107			gnba->realname = (char *)(b.base) + b.used;
108			gnba->realnamelen = client->recv_buffer.used - b.used;
109		} else {
110			naliases = gnba->naliases;
111			if (naliases >= LWRES_MAX_ALIASES)
112				break;
113			gnba->aliases[naliases] = (char *)(b.base) + b.used;
114			gnba->aliaslen[naliases] =
115				client->recv_buffer.used - b.used;
116			gnba->naliases++;
117		}
118	}
119
120	dns_byaddr_destroy(&client->byaddr);
121	isc_event_free(&event);
122
123	/*
124	 * Render the packet.
125	 */
126	client->pkt.recvlength = LWRES_RECVLENGTH;
127	client->pkt.authtype = 0; /* XXXMLG */
128	client->pkt.authlength = 0;
129	client->pkt.result = LWRES_R_SUCCESS;
130
131	lwres = lwres_gnbaresponse_render(cm->lwctx,
132					  gnba, &client->pkt, &lwb);
133	if (lwres != LWRES_R_SUCCESS)
134		goto out;
135
136	r.base = lwb.base;
137	r.length = lwb.used;
138	client->sendbuf = r.base;
139	client->sendlength = r.length;
140	result = ns_lwdclient_sendreply(client, &r);
141	if (result != ISC_R_SUCCESS)
142		goto out;
143
144	NS_LWDCLIENT_SETSEND(client);
145
146	return;
147
148 out:
149	if (client->byaddr != NULL)
150		dns_byaddr_destroy(&client->byaddr);
151	if (lwb.base != NULL)
152		lwres_context_freemem(cm->lwctx,
153				      lwb.base, lwb.length);
154
155	if (event != NULL)
156		isc_event_free(&event);
157}
158
159static void
160start_byaddr(ns_lwdclient_t *client) {
161	isc_result_t result;
162	ns_lwdclientmgr_t *cm;
163
164	cm = client->clientmgr;
165
166	INSIST(client->byaddr == NULL);
167
168	result = dns_byaddr_create(cm->mctx, &client->na, cm->view,
169				   client->options, cm->task, byaddr_done,
170				   client, &client->byaddr);
171	if (result != ISC_R_SUCCESS) {
172		ns_lwdclient_errorpktsend(client, LWRES_R_FAILURE);
173		return;
174	}
175}
176
177static void
178init_gnba(ns_lwdclient_t *client) {
179	int i;
180
181	/*
182	 * Initialize the real name and alias arrays in the reply we're
183	 * going to build up.
184	 */
185	for (i = 0; i < LWRES_MAX_ALIASES; i++) {
186		client->aliases[i] = NULL;
187		client->aliaslen[i] = 0;
188	}
189	for (i = 0; i < LWRES_MAX_ADDRS; i++) {
190		client->addrs[i].family = 0;
191		client->addrs[i].length = 0;
192		memset(client->addrs[i].address, 0, LWRES_ADDR_MAXLEN);
193		LWRES_LINK_INIT(&client->addrs[i], link);
194	}
195
196	client->gnba.naliases = 0;
197	client->gnba.realname = NULL;
198	client->gnba.aliases = client->aliases;
199	client->gnba.realnamelen = 0;
200	client->gnba.aliaslen = client->aliaslen;
201	client->gnba.base = NULL;
202	client->gnba.baselen = 0;
203	isc_buffer_init(&client->recv_buffer, client->buffer, LWRES_RECVLENGTH);
204}
205
206void
207ns_lwdclient_processgnba(ns_lwdclient_t *client, lwres_buffer_t *b) {
208	lwres_gnbarequest_t *req;
209	isc_result_t result;
210	isc_sockaddr_t sa;
211	ns_lwdclientmgr_t *cm;
212
213	REQUIRE(NS_LWDCLIENT_ISRECVDONE(client));
214	INSIST(client->byaddr == NULL);
215
216	cm = client->clientmgr;
217	req = NULL;
218
219	result = lwres_gnbarequest_parse(cm->lwctx,
220					 b, &client->pkt, &req);
221	if (result != LWRES_R_SUCCESS)
222		goto out;
223
224	client->options = 0;
225	if (req->addr.family == LWRES_ADDRTYPE_V4) {
226		client->na.family = AF_INET;
227		if (req->addr.length != 4)
228			goto out;
229		memmove(&client->na.type.in, req->addr.address, 4);
230	} else if (req->addr.family == LWRES_ADDRTYPE_V6) {
231		client->na.family = AF_INET6;
232		if (req->addr.length != 16)
233			goto out;
234		memmove(&client->na.type.in6, req->addr.address, 16);
235	} else {
236		goto out;
237	}
238	isc_sockaddr_fromnetaddr(&sa, &client->na, 53);
239
240	ns_lwdclient_log(50, "client %p looking for addrtype %08x",
241			 client, req->addr.family);
242
243	/*
244	 * We no longer need to keep this around.
245	 */
246	lwres_gnbarequest_free(cm->lwctx, &req);
247
248	/*
249	 * Initialize the real name and alias arrays in the reply we're
250	 * going to build up.
251	 */
252	init_gnba(client);
253	client->options = 0;
254
255	/*
256	 * Start the find.
257	 */
258	start_byaddr(client);
259
260	return;
261
262	/*
263	 * We're screwed.  Return an error packet to our caller.
264	 */
265 out:
266	if (req != NULL)
267		lwres_gnbarequest_free(cm->lwctx, &req);
268
269	ns_lwdclient_errorpktsend(client, LWRES_R_FAILURE);
270}
271