ueventd.c revision 44b65d047cc39baf30e21bfd8dd438f6bc1f77f5 
1/*
2 * Copyright (C) 2010 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include <poll.h>
18#include <fcntl.h>
19#include <string.h>
20#include <stdlib.h>
21#include <stdio.h>
22#include <ctype.h>
23#include <private/android_filesystem_config.h>
24
25#include "ueventd.h"
26#include "log.h"
27#include "util.h"
28#include "devices.h"
29#include "ueventd_parser.h"
30
31static char hardware[32];
32static unsigned revision = 0;
33
34int ueventd_main(int argc, char **argv)
35{
36    struct pollfd ufd;
37    int nr;
38    char tmp[32];
39
40    open_devnull_stdio();
41    log_init();
42
43    INFO("starting ueventd\n");
44
45    get_hardware_name(hardware, &revision);
46
47    ueventd_parse_config_file("/ueventd.rc");
48
49    snprintf(tmp, sizeof(tmp), "/ueventd.%s.rc", hardware);
50    ueventd_parse_config_file(tmp);
51
52    device_init();
53
54    ufd.events = POLLIN;
55    ufd.fd = get_device_fd();
56
57    while(1) {
58        ufd.revents = 0;
59        nr = poll(&ufd, 1, -1);
60        if (nr <= 0)
61            continue;
62        if (ufd.revents == POLLIN)
63               handle_device_fd();
64    }
65}
66
67static int get_android_id(const char *id)
68{
69    unsigned int i;
70    for (i = 0; i < ARRAY_SIZE(android_ids); i++)
71        if (!strcmp(id, android_ids[i].name))
72            return android_ids[i].aid;
73    return 0;
74}
75
76void set_device_permission(int nargs, char **args)
77{
78    char *name;
79    mode_t perm;
80    uid_t uid;
81    gid_t gid;
82    int prefix = 0;
83    char *endptr;
84    int ret;
85    char *tmp = 0;
86
87    if (nargs == 0)
88        return;
89
90    if (args[0][0] == '#')
91        return;
92
93    if (nargs != 4) {
94        ERROR("invalid line ueventd.rc line for '%s'\n", args[0]);
95        return;
96    }
97
98    name = args[0];
99    /* If path starts with mtd@ lookup the mount number. */
100    if (!strncmp(name, "mtd@", 4)) {
101        int n = mtd_name_to_number(name + 4);
102        if (n >= 0)
103            asprintf(&tmp, "/dev/mtd/mtd%d", n);
104        name = tmp;
105    } else {
106        int len = strlen(name);
107        if (name[len - 1] == '*') {
108            prefix = 1;
109            name[len - 1] = '\0';
110        }
111    }
112
113    perm = strtol(args[1], &endptr, 8);
114    if (!endptr || *endptr != '\0') {
115        ERROR("invalid mode '%s'\n", args[1]);
116        free(tmp);
117        return;
118    }
119
120    ret = get_android_id(args[2]);
121    if (ret < 0) {
122        ERROR("invalid uid '%s'\n", args[2]);
123        free(tmp);
124        return;
125    }
126    uid = ret;
127
128    ret = get_android_id(args[3]);
129    if (ret < 0) {
130        ERROR("invalid gid '%s'\n", args[3]);
131        free(tmp);
132        return;
133    }
134    gid = ret;
135
136    add_dev_perms(name, perm, uid, gid, prefix);
137    free(tmp);
138}
139