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 <signal.h>
24
25#include <private/android_filesystem_config.h>
26
27#include "ueventd.h"
28#include "log.h"
29#include "util.h"
30#include "devices.h"
31#include "ueventd_parser.h"
32
33static char hardware[32];
34static unsigned revision = 0;
35
36static void import_kernel_nv(char *name, int in_qemu)
37{
38    if (*name != '\0') {
39        char *value = strchr(name, '=');
40        if (value != NULL) {
41            *value++ = 0;
42            if (!strcmp(name,"androidboot.hardware"))
43            {
44                strlcpy(hardware, value, sizeof(hardware));
45            }
46        }
47    }
48}
49
50int ueventd_main(int argc, char **argv)
51{
52    struct pollfd ufd;
53    int nr;
54    char tmp[32];
55
56        /* Prevent fire-and-forget children from becoming zombies.
57         * If we should need to wait() for some children in the future
58         * (as opposed to none right now), double-forking here instead
59         * of ignoring SIGCHLD may be the better solution.
60         */
61    signal(SIGCHLD, SIG_IGN);
62
63    open_devnull_stdio();
64    klog_init();
65
66    INFO("starting ueventd\n");
67
68    /* Respect hardware passed in through the kernel cmd line. Here we will look
69     * for androidboot.hardware param in kernel cmdline, and save its value in
70     * hardware[]. */
71    import_kernel_cmdline(0, import_kernel_nv);
72
73    get_hardware_name(hardware, &revision);
74
75    ueventd_parse_config_file("/ueventd.rc");
76
77    snprintf(tmp, sizeof(tmp), "/ueventd.%s.rc", hardware);
78    ueventd_parse_config_file(tmp);
79
80    device_init();
81
82    ufd.events = POLLIN;
83    ufd.fd = get_device_fd();
84
85    while(1) {
86        ufd.revents = 0;
87        nr = poll(&ufd, 1, -1);
88        if (nr <= 0)
89            continue;
90        if (ufd.revents == POLLIN)
91               handle_device_fd();
92    }
93}
94
95static int get_android_id(const char *id)
96{
97    unsigned int i;
98    for (i = 0; i < ARRAY_SIZE(android_ids); i++)
99        if (!strcmp(id, android_ids[i].name))
100            return android_ids[i].aid;
101    return 0;
102}
103
104void set_device_permission(int nargs, char **args)
105{
106    char *name;
107    char *attr = 0;
108    mode_t perm;
109    uid_t uid;
110    gid_t gid;
111    int prefix = 0;
112    char *endptr;
113    int ret;
114    char *tmp = 0;
115
116    if (nargs == 0)
117        return;
118
119    if (args[0][0] == '#')
120        return;
121
122    name = args[0];
123
124    if (!strncmp(name,"/sys/", 5) && (nargs == 5)) {
125        INFO("/sys/ rule %s %s\n",args[0],args[1]);
126        attr = args[1];
127        args++;
128        nargs--;
129    }
130
131    if (nargs != 4) {
132        ERROR("invalid line ueventd.rc line for '%s'\n", args[0]);
133        return;
134    }
135
136    /* If path starts with mtd@ lookup the mount number. */
137    if (!strncmp(name, "mtd@", 4)) {
138        int n = mtd_name_to_number(name + 4);
139        if (n >= 0)
140            asprintf(&tmp, "/dev/mtd/mtd%d", n);
141        name = tmp;
142    } else {
143        int len = strlen(name);
144        if (name[len - 1] == '*') {
145            prefix = 1;
146            name[len - 1] = '\0';
147        }
148    }
149
150    perm = strtol(args[1], &endptr, 8);
151    if (!endptr || *endptr != '\0') {
152        ERROR("invalid mode '%s'\n", args[1]);
153        free(tmp);
154        return;
155    }
156
157    ret = get_android_id(args[2]);
158    if (ret < 0) {
159        ERROR("invalid uid '%s'\n", args[2]);
160        free(tmp);
161        return;
162    }
163    uid = ret;
164
165    ret = get_android_id(args[3]);
166    if (ret < 0) {
167        ERROR("invalid gid '%s'\n", args[3]);
168        free(tmp);
169        return;
170    }
171    gid = ret;
172
173    add_dev_perms(name, attr, perm, uid, gid, prefix);
174    free(tmp);
175}
176