1 /*        $NetBSD: client.c,v 1.7 2012/10/14 08:31:35 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 1.7 2012/10/14 08:31:35 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 *);
40 static void client_query(void);
41 
42 void
client_init(void)43 client_init(void)
44 {
45           struct sockaddr_bt sa;
46           channel_t *chan;
47           socklen_t len;
48           int fd, n;
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(n);
106           if (getsockopt(fd, SOL_SOCKET, SO_RCVBUF, &n, &len) == -1) {
107                     log_err("Could not read SO_RCVBUF");
108                     exit(EXIT_FAILURE);
109           }
110           if (n < 10 * mru) {
111                     n = 10 * mru;
112                     if (setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &n, sizeof(n)) == -1)
113                               log_info("Could not increase SO_RCVBUF (to %d)", n);
114           }
115 
116           len = sizeof(mtu);
117           if (getsockopt(fd, BTPROTO_L2CAP, SO_L2CAP_OMTU, &mtu, &len) == -1) {
118                     log_err("Could not get L2CAP OMTU: %m");
119                     exit(EXIT_FAILURE);
120           }
121           if (mtu < BNEP_MTU_MIN) {
122                     log_err("L2CAP OMTU too small (%d)", mtu);
123                     exit(EXIT_FAILURE);
124           }
125 
126           len = sizeof(n);
127           if (getsockopt(fd, SOL_SOCKET, SO_SNDBUF, &n, &len) == -1) {
128                     log_err("Could not get socket send buffer size: %m");
129                     close(fd);
130                     return;
131           }
132           if (n < (mtu * 2)) {
133                     n = mtu * 2;
134                     if (setsockopt(fd, SOL_SOCKET, SO_SNDBUF, &n, sizeof(n)) == -1) {
135                               log_err("Could not set socket send buffer size (%d): %m", n);
136                               close(fd);
137                               return;
138                     }
139           }
140           n = mtu;
141           if (setsockopt(fd, SOL_SOCKET, SO_SNDLOWAT, &n, sizeof(n)) == -1) {
142                     log_err("Could not set socket low water mark (%d): %m", n);
143                     close(fd);
144                     return;
145           }
146 
147           chan = channel_alloc();
148           if (chan == NULL)
149                     exit(EXIT_FAILURE);
150 
151           chan->send = bnep_send;
152           chan->recv = bnep_recv;
153           chan->down = client_down;
154           chan->mru = mru;
155           chan->mtu = mtu;
156           b2eaddr(chan->raddr, &remote_bdaddr);
157           b2eaddr(chan->laddr, &local_bdaddr);
158           chan->state = CHANNEL_WAIT_CONNECT_RSP;
159           channel_timeout(chan, 10);
160           if (!channel_open(chan, fd))
161                     exit(EXIT_FAILURE);
162 
163           bnep_send_control(chan, BNEP_SETUP_CONNECTION_REQUEST,
164               2, service_class, SDP_SERVICE_CLASS_PANU);
165 }
166 
167 static void
client_down(channel_t * chan)168 client_down(channel_t *chan)
169 {
170 
171           log_err("Client connection shut down, exiting");
172           exit(EXIT_FAILURE);
173 }
174 
175 static void
client_query(void)176 client_query(void)
177 {
178           uint8_t buf[12];    /* enough for SSP and AIL both */
179           sdp_session_t ss;
180           sdp_data_t ssp, ail, rsp, rec, value, pdl, seq;
181           uintmax_t psm;
182           uint16_t attr;
183           bool rv;
184 
185           ss = sdp_open(&local_bdaddr, &remote_bdaddr);
186           if (ss == NULL) {
187                     log_err("%s: %m", service_type);
188                     exit(EXIT_FAILURE);
189           }
190 
191           log_info("Searching for %s service at %s",
192               service_type, bt_ntoa(&remote_bdaddr, NULL));
193 
194           seq.next = buf;
195           seq.end = buf + sizeof(buf);
196 
197           /*
198            * build ServiceSearchPattern (9 bytes)
199            *
200            *        uuid16    "service_class"
201            *        uuid16    L2CAP
202            *        uuid16    BNEP
203            */
204           ssp.next = seq.next;
205           sdp_put_uuid16(&seq, service_class);
206           sdp_put_uuid16(&seq, SDP_UUID_PROTOCOL_L2CAP);
207           sdp_put_uuid16(&seq, SDP_UUID_PROTOCOL_BNEP);
208           ssp.end = seq.next;
209 
210           /*
211            * build AttributeIDList (3 bytes)
212            *
213            *        uint16    ProtocolDescriptorList
214            */
215           ail.next = seq.next;
216           sdp_put_uint16(&seq, SDP_ATTR_PROTOCOL_DESCRIPTOR_LIST);
217           ail.end = seq.next;
218 
219           rv = sdp_service_search_attribute(ss, &ssp, &ail, &rsp);
220           if (!rv) {
221                     log_err("%s: %m", service_type);
222                     exit(EXIT_FAILURE);
223           }
224 
225           /*
226            * we expect the response to contain a list of records
227            * containing a ProtocolDescriptorList. Find the first
228            * one containing L2CAP and BNEP protocols and extract
229            * the PSM.
230            */
231           rv = false;
232           while (!rv && sdp_get_seq(&rsp, &rec)) {
233                     if (!sdp_get_attr(&rec, &attr, &value)
234                         || attr != SDP_ATTR_PROTOCOL_DESCRIPTOR_LIST)
235                               continue;
236 
237                     sdp_get_alt(&value, &value);  /* drop any alt header */
238                     while (!rv && sdp_get_seq(&value, &pdl)) {
239                               if (sdp_get_seq(&pdl, &seq)
240                                   && sdp_match_uuid16(&seq, SDP_UUID_PROTOCOL_L2CAP)
241                                   && sdp_get_uint(&seq, &psm)
242                                   && sdp_get_seq(&pdl, &seq)
243                                   && sdp_match_uuid16(&seq, SDP_UUID_PROTOCOL_BNEP))
244                                         rv = true;
245                     }
246           }
247 
248           sdp_close(ss);
249 
250           if (!rv) {
251                     log_err("%s query failed", service_type);
252                     exit(EXIT_FAILURE);
253           }
254 
255           l2cap_psm = (uint16_t)psm;
256           log_info("Found PSM %u for service %s", l2cap_psm, service_type);
257 }
258