1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
|
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <asm/setup.h>
static char new_command_line[COMMAND_LINE_SIZE];
static int cmdline_proc_show(struct seq_file *m, void *v)
{
seq_printf(m, "%s\n", new_command_line);
return 0;
}
static int cmdline_proc_open(struct inode *inode, struct file *file)
{
return single_open(file, cmdline_proc_show, NULL);
}
static const struct file_operations cmdline_proc_fops = {
.open = cmdline_proc_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static void remove_flag(char *cmd, const char *flag)
{
char *start_addr, *end_addr;
/* Ensure all instances of a flag are removed */
while ((start_addr = strstr(cmd, flag))) {
end_addr = strchr(start_addr, ' ');
if (end_addr)
memmove(start_addr, end_addr + 1, strlen(end_addr));
else
*(start_addr - 1) = '\0';
}
}
static void remove_safetynet_flags(char *cmd)
{
remove_flag(cmd, "androidboot.enable_dm_verity=");
remove_flag(cmd, "androidboot.secboot=");
remove_flag(cmd, "androidboot.verifiedbootstate=");
remove_flag(cmd, "androidboot.veritymode=");
}
static int __init proc_cmdline_init(void)
{
strcpy(new_command_line, saved_command_line);
/*
* Remove various flags from command line seen by userspace in order to
* pass SafetyNet CTS check.
*/
remove_safetynet_flags(new_command_line);
proc_create("cmdline", 0, NULL, &cmdline_proc_fops);
return 0;
}
fs_initcall(proc_cmdline_init);
|
