1/*	$NetBSD: client.c,v 1.5 2011/02/08 21:59:50 plunky Exp $	*/
2
3/*-
4 * Copyright (c) 2008-2009 Iain Hibbert
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28#include <sys/cdefs.h>
29__RCSID("$NetBSD: client.c,v 1.5 2011/02/08 21:59:50 plunky Exp $");
30
31#include <bluetooth.h>
32#include <errno.h>
33#include <sdp.h>
34#include <unistd.h>
35
36#include "btpand.h"
37#include "bnep.h"
38
39__dead static void client_down(channel_t *);
40static void client_query(void);
41
42void
43client_init(void)
44{
45	struct sockaddr_bt sa;
46	channel_t *chan;
47	socklen_t len;
48	int fd, bufsize;
49	uint16_t mru, mtu;
50
51	if (bdaddr_any(&remote_bdaddr))
52		return;
53
54	if (service_type)
55		client_query();
56
57	fd = socket(PF_BLUETOOTH, SOCK_SEQPACKET, BTPROTO_L2CAP);
58	if (fd == -1) {
59		log_err("Could not open L2CAP socket: %m");
60		exit(EXIT_FAILURE);
61	}
62
63	memset(&sa, 0, sizeof(sa));
64	sa.bt_family = AF_BLUETOOTH;
65	sa.bt_len = sizeof(sa);
66	bdaddr_copy(&sa.bt_bdaddr, &local_bdaddr);
67	if (bind(fd, (struct sockaddr *)&sa, sizeof(sa)) == -1) {
68		log_err("Could not bind client socket: %m");
69		exit(EXIT_FAILURE);
70	}
71
72	if (setsockopt(fd, BTPROTO_L2CAP, SO_L2CAP_LM,
73	    &l2cap_mode, sizeof(l2cap_mode)) == -1) {
74		log_err("Could not set link mode (0x%4.4x): %m", l2cap_mode);
75		exit(EXIT_FAILURE);
76	}
77
78	mru = BNEP_MTU_MIN;
79	if (setsockopt(fd, BTPROTO_L2CAP, SO_L2CAP_IMTU,
80	    &mru, sizeof(mru)) == -1) {
81		log_err("Could not set L2CAP IMTU (%d): %m", mru);
82		exit(EXIT_FAILURE);
83	}
84
85	log_info("Opening connection to service 0x%4.4x at %s",
86	    service_class, bt_ntoa(&remote_bdaddr, NULL));
87
88	sa.bt_psm = l2cap_psm;
89	bdaddr_copy(&sa.bt_bdaddr, &remote_bdaddr);
90	if (connect(fd, (struct sockaddr *)&sa, sizeof(sa)) == -1) {
91		log_err("Could not connect: %m");
92		exit(EXIT_FAILURE);
93	}
94
95	len = sizeof(mru);
96	if (getsockopt(fd, BTPROTO_L2CAP, SO_L2CAP_IMTU, &mru, &len) == -1) {
97		log_err("Could not get IMTU: %m");
98		exit(EXIT_FAILURE);
99	}
100	if (mru < BNEP_MTU_MIN) {
101		log_err("L2CAP IMTU too small (%d)", mru);
102		exit(EXIT_FAILURE);
103	}
104
105	len = sizeof(bufsize);
106	if (getsockopt(fd, SOL_SOCKET, SO_RCVBUF, &bufsize, &len) == -1) {
107		log_err("Could not read SO_RCVBUF");
108		exit(EXIT_FAILURE);
109	}
110	if (bufsize < 10 * mru) {
111		bufsize = 10 * mru;
112		if (setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &bufsize,
113		    sizeof(bufsize)) == -1)
114			log_info("Could not increase SO_RCVBUF (from %d)",
115			    bufsize);
116	}
117
118	len = sizeof(mtu);
119	if (getsockopt(fd, BTPROTO_L2CAP, SO_L2CAP_OMTU, &mtu, &len) == -1) {
120		log_err("Could not get L2CAP OMTU: %m");
121		exit(EXIT_FAILURE);
122	}
123	if (mtu < BNEP_MTU_MIN) {
124		log_err("L2CAP OMTU too small (%d)", mtu);
125		exit(EXIT_FAILURE);
126	}
127
128	chan = channel_alloc();
129	if (chan == NULL)
130		exit(EXIT_FAILURE);
131
132	chan->send = bnep_send;
133	chan->recv = bnep_recv;
134	chan->down = client_down;
135	chan->mru = mru;
136	chan->mtu = mtu;
137	b2eaddr(chan->raddr, &remote_bdaddr);
138	b2eaddr(chan->laddr, &local_bdaddr);
139	chan->state = CHANNEL_WAIT_CONNECT_RSP;
140	channel_timeout(chan, 10);
141	if (!channel_open(chan, fd))
142		exit(EXIT_FAILURE);
143
144	bnep_send_control(chan, BNEP_SETUP_CONNECTION_REQUEST,
145	    2, service_class, SDP_SERVICE_CLASS_PANU);
146}
147
148static void
149client_down(channel_t *chan)
150{
151
152	log_err("Client connection shut down, exiting");
153	exit(EXIT_FAILURE);
154}
155
156static void
157client_query(void)
158{
159	uint8_t buf[12];	/* enough for SSP and AIL both */
160	sdp_session_t ss;
161	sdp_data_t ssp, ail, rsp, rec, value, pdl, seq;
162	uintmax_t psm;
163	uint16_t attr;
164	bool rv;
165
166	ss = sdp_open(&local_bdaddr, &remote_bdaddr);
167	if (ss == NULL) {
168		log_err("%s: %m", service_type);
169		exit(EXIT_FAILURE);
170	}
171
172	log_info("Searching for %s service at %s",
173	    service_type, bt_ntoa(&remote_bdaddr, NULL));
174
175	seq.next = buf;
176	seq.end = buf + sizeof(buf);
177
178	/*
179	 * build ServiceSearchPattern (9 bytes)
180	 *
181	 *	uuid16	"service_class"
182	 *	uuid16	L2CAP
183	 *	uuid16	BNEP
184	 */
185	ssp.next = seq.next;
186	sdp_put_uuid16(&seq, service_class);
187	sdp_put_uuid16(&seq, SDP_UUID_PROTOCOL_L2CAP);
188	sdp_put_uuid16(&seq, SDP_UUID_PROTOCOL_BNEP);
189	ssp.end = seq.next;
190
191	/*
192	 * build AttributeIDList (3 bytes)
193	 *
194	 *	uint16	ProtocolDescriptorList
195	 */
196	ail.next = seq.next;
197	sdp_put_uint16(&seq, SDP_ATTR_PROTOCOL_DESCRIPTOR_LIST);
198	ail.end = seq.next;
199
200	rv = sdp_service_search_attribute(ss, &ssp, &ail, &rsp);
201	if (!rv) {
202		log_err("%s: %m", service_type);
203		exit(EXIT_FAILURE);
204	}
205
206	/*
207	 * we expect the response to contain a list of records
208	 * containing a ProtocolDescriptorList. Find the first
209	 * one containing L2CAP and BNEP protocols and extract
210	 * the PSM.
211	 */
212	rv = false;
213	while (!rv && sdp_get_seq(&rsp, &rec)) {
214		if (!sdp_get_attr(&rec, &attr, &value)
215		    || attr != SDP_ATTR_PROTOCOL_DESCRIPTOR_LIST)
216			continue;
217
218		sdp_get_alt(&value, &value);	/* drop any alt header */
219		while (!rv && sdp_get_seq(&value, &pdl)) {
220			if (sdp_get_seq(&pdl, &seq)
221			    && sdp_match_uuid16(&seq, SDP_UUID_PROTOCOL_L2CAP)
222			    && sdp_get_uint(&seq, &psm)
223			    && sdp_get_seq(&pdl, &seq)
224			    && sdp_match_uuid16(&seq, SDP_UUID_PROTOCOL_BNEP))
225				rv = true;
226		}
227	}
228
229	sdp_close(ss);
230
231	if (!rv) {
232		log_err("%s query failed", service_type);
233		exit(EXIT_FAILURE);
234	}
235
236	l2cap_psm = (uint16_t)psm;
237	log_info("Found PSM %u for service %s", l2cap_psm, service_type);
238}
239