1 /*
2 * Copyright (C) 2008 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 <stdarg.h>
18 #include <stdlib.h>
19 #include <stdio.h>
20 #include <string.h>
21 #include <fcntl.h>
22 #include <ctype.h>
23 #include <errno.h>
24
25 #include <sys/stat.h>
26 #include <sys/types.h>
27 #include <sys/socket.h>
28 #include <sys/un.h>
29
30 /* for ANDROID_SOCKET_* */
31 #include <cutils/sockets.h>
32
33 #include <private/android_filesystem_config.h>
34
35 #include "init.h"
36
37 static int log_fd = -1;
38 /* Inital log level before init.rc is parsed and this this is reset. */
39 static int log_level = LOG_DEFAULT_LEVEL;
40
41
log_set_level(int level)42 void log_set_level(int level) {
43 log_level = level;
44 }
45
log_init(void)46 void log_init(void)
47 {
48 static const char *name = "/dev/__kmsg__";
49 if (mknod(name, S_IFCHR | 0600, (1 << 8) | 11) == 0) {
50 log_fd = open(name, O_WRONLY);
51 fcntl(log_fd, F_SETFD, FD_CLOEXEC);
52 unlink(name);
53 }
54 }
55
56 #define LOG_BUF_MAX 512
57
log_write(int level,const char * fmt,...)58 void log_write(int level, const char *fmt, ...)
59 {
60 char buf[LOG_BUF_MAX];
61 va_list ap;
62
63 if (level > log_level) return;
64 if (log_fd < 0) return;
65
66 va_start(ap, fmt);
67 vsnprintf(buf, LOG_BUF_MAX, fmt, ap);
68 buf[LOG_BUF_MAX - 1] = 0;
69 va_end(ap);
70 write(log_fd, buf, strlen(buf));
71 }
72
73 /*
74 * android_name_to_id - returns the integer uid/gid associated with the given
75 * name, or -1U on error.
76 */
android_name_to_id(const char * name)77 static unsigned int android_name_to_id(const char *name)
78 {
79 struct android_id_info *info = android_ids;
80 unsigned int n;
81
82 for (n = 0; n < android_id_count; n++) {
83 if (!strcmp(info[n].name, name))
84 return info[n].aid;
85 }
86
87 return -1U;
88 }
89
90 /*
91 * decode_uid - decodes and returns the given string, which can be either the
92 * numeric or name representation, into the integer uid or gid. Returns -1U on
93 * error.
94 */
decode_uid(const char * s)95 unsigned int decode_uid(const char *s)
96 {
97 unsigned int v;
98
99 if (!s || *s == '\0')
100 return -1U;
101 if (isalpha(s[0]))
102 return android_name_to_id(s);
103
104 errno = 0;
105 v = (unsigned int) strtoul(s, 0, 0);
106 if (errno)
107 return -1U;
108 return v;
109 }
110
111 /*
112 * create_socket - creates a Unix domain socket in ANDROID_SOCKET_DIR
113 * ("/dev/socket") as dictated in init.rc. This socket is inherited by the
114 * daemon. We communicate the file descriptor's value via the environment
115 * variable ANDROID_SOCKET_ENV_PREFIX<name> ("ANDROID_SOCKET_foo").
116 */
create_socket(const char * name,int type,mode_t perm,uid_t uid,gid_t gid)117 int create_socket(const char *name, int type, mode_t perm, uid_t uid, gid_t gid)
118 {
119 struct sockaddr_un addr;
120 int fd, ret;
121
122 fd = socket(PF_UNIX, type, 0);
123 if (fd < 0) {
124 ERROR("Failed to open socket '%s': %s\n", name, strerror(errno));
125 return -1;
126 }
127
128 memset(&addr, 0 , sizeof(addr));
129 addr.sun_family = AF_UNIX;
130 snprintf(addr.sun_path, sizeof(addr.sun_path), ANDROID_SOCKET_DIR"/%s",
131 name);
132
133 ret = unlink(addr.sun_path);
134 if (ret != 0 && errno != ENOENT) {
135 ERROR("Failed to unlink old socket '%s': %s\n", name, strerror(errno));
136 goto out_close;
137 }
138
139 ret = bind(fd, (struct sockaddr *) &addr, sizeof (addr));
140 if (ret) {
141 ERROR("Failed to bind socket '%s': %s\n", name, strerror(errno));
142 goto out_unlink;
143 }
144
145 chown(addr.sun_path, uid, gid);
146 chmod(addr.sun_path, perm);
147
148 INFO("Created socket '%s' with mode '%o', user '%d', group '%d'\n",
149 addr.sun_path, perm, uid, gid);
150
151 return fd;
152
153 out_unlink:
154 unlink(addr.sun_path);
155 out_close:
156 close(fd);
157 return -1;
158 }
159
160 /* reads a file, making sure it is terminated with \n \0 */
read_file(const char * fn,unsigned * _sz)161 void *read_file(const char *fn, unsigned *_sz)
162 {
163 char *data;
164 int sz;
165 int fd;
166
167 data = 0;
168 fd = open(fn, O_RDONLY);
169 if(fd < 0) return 0;
170
171 sz = lseek(fd, 0, SEEK_END);
172 if(sz < 0) goto oops;
173
174 if(lseek(fd, 0, SEEK_SET) != 0) goto oops;
175
176 data = (char*) malloc(sz + 2);
177 if(data == 0) goto oops;
178
179 if(read(fd, data, sz) != sz) goto oops;
180 close(fd);
181 data[sz] = '\n';
182 data[sz+1] = 0;
183 if(_sz) *_sz = sz;
184 return data;
185
186 oops:
187 close(fd);
188 if(data != 0) free(data);
189 return 0;
190 }
191
list_init(struct listnode * node)192 void list_init(struct listnode *node)
193 {
194 node->next = node;
195 node->prev = node;
196 }
197
list_add_tail(struct listnode * head,struct listnode * item)198 void list_add_tail(struct listnode *head, struct listnode *item)
199 {
200 item->next = head;
201 item->prev = head->prev;
202 head->prev->next = item;
203 head->prev = item;
204 }
205
list_remove(struct listnode * item)206 void list_remove(struct listnode *item)
207 {
208 item->next->prev = item->prev;
209 item->prev->next = item->next;
210 }
211
212