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 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 50 int 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 95 static 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 } 103 104 void 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