network_discovery.c revision bc849f14533a4a1fad676d31d0353909fa9d94be 
1/*
2 * Copyright (c) 2009-2013, Google Inc.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *  * Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 *  * Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in
12 *    the documentation and/or other materials provided with the
13 *    distribution.
14 *  * Neither the name of Google, Inc. nor the names of its contributors
15 *    may be used to endorse or promote products derived from this
16 *    software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
21 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
22 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
24 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
25 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
26 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
27 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
28 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32#include <stdio.h>
33#include <string.h>
34#include <dns_sd.h>
35#include <cutils/properties.h>
36#include <unistd.h>
37
38#include "debug.h"
39#include "network_discovery.h"
40#include "utils.h"
41
42#define MDNS_SERVICE_NAME "mdnsd"
43#define MDNS_SERVICE_STATUS "init.svc.mdnsd"
44#define FASTBOOTD_TYPE "_fastbootd._tcp"
45#define FASTBOOTD_DOMAIN "local."
46#define FASTBOOTD_NAME "fastbootd"
47
48
49static void reg_reply(DNSServiceRef sdref, const DNSServiceFlags flags, DNSServiceErrorType errorCode,
50    const char *name, const char *regtype, const char *domain, void *context)
51{
52    (void)sdref;    // Unused
53    (void)flags;    // Unused
54    (void)context;  // Unused
55    if (errorCode == kDNSServiceErr_ServiceNotRunning) {
56        fprintf(stderr, "Error code %d\n", errorCode);
57    }
58
59
60    printf("Got a reply for service %s.%s%s: ", name, regtype, domain);
61
62    if (errorCode == kDNSServiceErr_NoError)
63    {
64        if (flags & kDNSServiceFlagsAdd)
65            printf("Name now registered and active\n");
66        else
67            printf("Name registration removed\n");
68        if (errorCode == kDNSServiceErr_NameConflict)
69            printf("Name in use, please choose another\n");
70        else
71            printf("Error %d\n", errorCode);
72
73        if (!(flags & kDNSServiceFlagsMoreComing)) fflush(stdout);
74    }
75}
76
77static int register_service() {
78    DNSServiceRef sdref = NULL;
79    const char *domain = FASTBOOTD_DOMAIN;
80    const char *type = FASTBOOTD_TYPE;
81    const char *host = NULL;
82    char name[PROP_VALUE_MAX];
83    uint16_t port = 22;
84    int flags = 0;
85    DNSServiceErrorType result;
86    property_get("ro.serialno", name, "");
87    if (!strcmp(name, "")) {
88        D(ERR, "No property serialno");
89        return -1;
90    }
91
92    result = DNSServiceRegister(&sdref, flags, kDNSServiceInterfaceIndexAny,
93                       name, type, domain, host, port,
94                       0, NULL, reg_reply, NULL);
95    if (result != kDNSServiceErr_NoError) {
96        D(ERR, "Unable to register service");
97        return -1;
98    }
99    return 0;
100}
101
102
103int network_discovery_init()
104{
105    D(INFO, "Starting discovery");
106    if (service_start(MDNS_SERVICE_NAME)) {
107        D(ERR, "Unable to start discovery");
108        return -1;
109    }
110
111    if (register_service()) {
112        D(ERR, "Unable to register service");
113        return -1;
114    }
115
116    return 0;
117}
118
119