1 /*
2 * Copyright (c) 2020-2021 Huawei Device Co., Ltd.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at
6 *
7 * http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
14 */
15 #include "device.h"
16
17 #include <unistd.h>
18 #include <errno.h>
19 #include <fcntl.h>
20 #include <sys/mount.h>
21 #include <sys/stat.h>
22 #include <sys/sysmacros.h>
23
24 #include <linux/major.h>
25 #include "init_log.h"
26
27 #define DEFAULT_RW_MODE (S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH)
28 #define DEFAULT_NO_AUTHORITY_MODE (S_IWUSR | S_IRUSR)
29
MountBasicFs(void)30 static void MountBasicFs(void)
31 {
32 if (access("dev/null", F_OK) != 0) {
33 INIT_LOGI("mount dev tmpfs");
34 if (mount("tmpfs", "/dev", "tmpfs", MS_NOSUID, "mode=0755") != 0) {
35 INIT_LOGE("Mount tmpfs failed. %s", strerror(errno));
36 }
37 } else {
38 INIT_LOGI("dev already mounted");
39 }
40 if (mount("tmpfs", "/mnt", "tmpfs", MS_NOSUID, "mode=0755") != 0) {
41 INIT_LOGE("Mount tmpfs failed. %s", strerror(errno));
42 }
43 if (mount(NULL, "/mnt", NULL, MS_SLAVE, NULL) != 0) {
44 INIT_LOGE("Mount tmpfs slave failed. %s", strerror(errno));
45 }
46 if (mkdir("/mnt/data", S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH) != 0) {
47 INIT_LOGE("mkdir /mnt/data failed. %s", strerror(errno));
48 }
49 if (mount("tmpfs", "/mnt/data", "tmpfs", MS_NOSUID, "mode=0755") != 0) {
50 INIT_LOGE("Mount tmpfs failed. %s", strerror(errno));
51 }
52 if (mount(NULL, "/mnt/data", NULL, MS_SHARED, NULL) != 0) {
53 INIT_LOGE("Mount tmpfs shared failed. %s", strerror(errno));
54 }
55 if (mount("tmpfs", "/storage", "tmpfs", MS_NOEXEC | MS_NODEV| MS_NOSUID, "mode=0755") != 0) {
56 INIT_LOGE("Mount storage failed. %s", strerror(errno));
57 }
58 struct stat st;
59 if (!(stat("/dev/pts", &st) == 0 && S_ISDIR(st.st_mode))) {
60 if (mkdir("/dev/pts", S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH) != 0) {
61 INIT_LOGE("mkdir /dev/pts failed. %s", strerror(errno));
62 }
63 if (mount("devpts", "/dev/pts", "devpts", 0, NULL) != 0) {
64 INIT_LOGE("Mount devpts failed. %s", strerror(errno));
65 }
66 }
67 if (mount("proc", "/proc", "proc", 0, "gid=3009,hidepid=2") != 0) {
68 INIT_LOGE("Mount procfs failed. %s", strerror(errno));
69 }
70 if (mount("sysfs", "/sys", "sysfs", 0, NULL) != 0) {
71 INIT_LOGE("Mount sysfs failed. %s", strerror(errno));
72 }
73 if (mount("selinuxfs", "/sys/fs/selinux", "selinuxfs", 0, NULL) != 0) {
74 INIT_LOGE("Mount selinuxfs failed. %s", strerror(errno));
75 }
76 }
77
CreateDeviceNode(void)78 static void CreateDeviceNode(void)
79 {
80 if (access("/dev/null", F_OK) != 0) {
81 if (mknod("/dev/null", S_IFCHR | DEFAULT_RW_MODE, makedev(MEM_MAJOR, DEV_NULL_MINOR)) != 0) {
82 INIT_LOGE("Create /dev/null device node failed. %s", strerror(errno));
83 }
84 }
85
86 if (access("/dev/random", F_OK) != 0) {
87 if (mknod("/dev/random", S_IFCHR | DEFAULT_RW_MODE, makedev(MEM_MAJOR, DEV_RANDOM_MINOR)) != 0) {
88 INIT_LOGE("Create /dev/random device node failed. %s", strerror(errno));
89 }
90 }
91
92 if (access("/dev/urandom", F_OK) != 0) {
93 if (mknod("/dev/urandom", S_IFCHR | DEFAULT_RW_MODE, makedev(MEM_MAJOR, DEV_URANDOM_MINOR)) != 0) {
94 INIT_LOGW("Create /dev/urandom device node failed. %s", strerror(errno));
95 }
96 }
97 }
98
EnableDevKmsg(void)99 static void EnableDevKmsg(void)
100 {
101 /* printk_devkmsg default value is ratelimit, We need to set "on" and remove the restrictions */
102 int fd = open("/proc/sys/kernel/printk_devkmsg", O_WRONLY | O_CLOEXEC, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
103 if (fd < 0) {
104 return;
105 }
106 char *kmsgStatus = "on";
107 write(fd, kmsgStatus, strlen(kmsgStatus) + 1);
108 close(fd);
109 fd = -1;
110 return;
111 }
112
CreateFsAndDeviceNode(void)113 void CreateFsAndDeviceNode(void)
114 {
115 MountBasicFs();
116 CreateDeviceNode();
117 EnableDevKmsg();
118 }
119