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
33 static char hardware[32];
34 static unsigned revision = 0;
35
import_kernel_nv(char * name,int in_qemu)36 static 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
ueventd_main(int argc,char ** argv)50 int ueventd_main(int argc, char **argv)
51 {
52 struct pollfd ufd;
53 int nr;
54 char tmp[32];
55
56 /*
57 * init sets the umask to 077 for forked processes. We need to
58 * create files with exact permissions, without modification by
59 * the umask.
60 */
61 umask(000);
62
63 /* Prevent fire-and-forget children from becoming zombies.
64 * If we should need to wait() for some children in the future
65 * (as opposed to none right now), double-forking here instead
66 * of ignoring SIGCHLD may be the better solution.
67 */
68 signal(SIGCHLD, SIG_IGN);
69
70 open_devnull_stdio();
71 klog_init();
72
73 INFO("starting ueventd\n");
74
75 /* Respect hardware passed in through the kernel cmd line. Here we will look
76 * for androidboot.hardware param in kernel cmdline, and save its value in
77 * hardware[]. */
78 import_kernel_cmdline(0, import_kernel_nv);
79
80 get_hardware_name(hardware, &revision);
81
82 ueventd_parse_config_file("/ueventd.rc");
83
84 snprintf(tmp, sizeof(tmp), "/ueventd.%s.rc", hardware);
85 ueventd_parse_config_file(tmp);
86
87 device_init();
88
89 ufd.events = POLLIN;
90 ufd.fd = get_device_fd();
91
92 while(1) {
93 ufd.revents = 0;
94 nr = poll(&ufd, 1, -1);
95 if (nr <= 0)
96 continue;
97 if (ufd.revents == POLLIN)
98 handle_device_fd();
99 }
100 }
101
get_android_id(const char * id)102 static int get_android_id(const char *id)
103 {
104 unsigned int i;
105 for (i = 0; i < ARRAY_SIZE(android_ids); i++)
106 if (!strcmp(id, android_ids[i].name))
107 return android_ids[i].aid;
108 return -1;
109 }
110
set_device_permission(int nargs,char ** args)111 void set_device_permission(int nargs, char **args)
112 {
113 char *name;
114 char *attr = 0;
115 mode_t perm;
116 uid_t uid;
117 gid_t gid;
118 int prefix = 0;
119 char *endptr;
120 int ret;
121 char *tmp = 0;
122
123 if (nargs == 0)
124 return;
125
126 if (args[0][0] == '#')
127 return;
128
129 name = args[0];
130
131 if (!strncmp(name,"/sys/", 5) && (nargs == 5)) {
132 INFO("/sys/ rule %s %s\n",args[0],args[1]);
133 attr = args[1];
134 args++;
135 nargs--;
136 }
137
138 if (nargs != 4) {
139 ERROR("invalid line ueventd.rc line for '%s'\n", args[0]);
140 return;
141 }
142
143 /* If path starts with mtd@ lookup the mount number. */
144 if (!strncmp(name, "mtd@", 4)) {
145 int n = mtd_name_to_number(name + 4);
146 if (n >= 0)
147 asprintf(&tmp, "/dev/mtd/mtd%d", n);
148 name = tmp;
149 } else {
150 int len = strlen(name);
151 if (name[len - 1] == '*') {
152 prefix = 1;
153 name[len - 1] = '\0';
154 }
155 }
156
157 perm = strtol(args[1], &endptr, 8);
158 if (!endptr || *endptr != '\0') {
159 ERROR("invalid mode '%s'\n", args[1]);
160 free(tmp);
161 return;
162 }
163
164 ret = get_android_id(args[2]);
165 if (ret < 0) {
166 ERROR("invalid uid '%s'\n", args[2]);
167 free(tmp);
168 return;
169 }
170 uid = ret;
171
172 ret = get_android_id(args[3]);
173 if (ret < 0) {
174 ERROR("invalid gid '%s'\n", args[3]);
175 free(tmp);
176 return;
177 }
178 gid = ret;
179
180 add_dev_perms(name, attr, perm, uid, gid, prefix);
181 free(tmp);
182 }
183