Magisk/native/jni/magiskhide/hide_policy.cpp
2019-06-04 22:27:19 -07:00

101 lines
2.4 KiB
C++

#include <sys/mount.h>
#include <magisk.h>
#include <utils.h>
#include <selinux.h>
#include <resetprop.h>
#include "magiskhide.h"
using namespace std;
static const char *prop_key[] =
{ "ro.boot.vbmeta.device_state", "ro.boot.verifiedbootstate", "ro.boot.flash.locked",
"ro.boot.veritymode", "ro.boot.warranty_bit", "ro.warranty_bit", "ro.debuggable",
"ro.secure", "ro.build.type", "ro.build.tags", "ro.build.selinux", nullptr };
static const char *prop_value[] =
{ "locked", "green", "1",
"enforcing", "0", "0", "0",
"1", "user", "release-keys", "0", nullptr };
void hide_sensitive_props() {
LOGI("hide_policy: Hiding sensitive props\n");
// Hide all sensitive props
for (int i = 0; prop_key[i]; ++i) {
auto value = getprop(prop_key[i]);
if (!value.empty() && value != prop_value[i])
setprop(prop_key[i], prop_value[i], false);
}
}
static inline void lazy_unmount(const char* mountpoint) {
if (umount2(mountpoint, MNT_DETACH) != -1)
LOGD("hide_policy: Unmounted (%s)\n", mountpoint);
}
void hide_daemon(int pid) {
RunFinally fin([=]() -> void {
// Send resume signal
tgkill(pid, pid, SIGCONT);
_exit(0);
});
hide_unmount(pid);
}
void hide_unmount(int pid) {
if (switch_mnt_ns(pid))
return;
LOGD("hide_policy: handling PID=[%d]\n", pid);
char val;
int fd = xopen(SELINUX_ENFORCE, O_RDONLY);
xxread(fd, &val, sizeof(val));
close(fd);
// Permissive
if (val == '0') {
chmod(SELINUX_ENFORCE, 0640);
chmod(SELINUX_POLICY, 0440);
}
getprop([](const char *name, auto, auto) -> void {
if (strstr(name, "magisk"))
deleteprop(name);
}, nullptr, false);
vector<string> targets;
// Unmount dummy skeletons and /sbin links
file_readline("/proc/self/mounts", [&](string_view s) -> bool {
if (str_contains(s, "tmpfs /system/") || str_contains(s, "tmpfs /vendor/") ||
str_contains(s, "tmpfs /sbin")) {
char *path = (char *) s.data();
// Skip first token
strtok_r(nullptr, " ", &path);
targets.emplace_back(strtok_r(nullptr, " ", &path));
}
return true;
});
for (auto &s : targets)
lazy_unmount(s.data());
targets.clear();
// Unmount all Magisk created mounts
file_readline("/proc/self/mounts", [&](string_view s) -> bool {
if (str_contains(s, BLOCKDIR)) {
char *path = (char *) s.data();
// Skip first token
strtok_r(nullptr, " ", &path);
targets.emplace_back(strtok_r(nullptr, " ", &path));
}
return true;
});
for (auto &s : targets)
lazy_unmount(s.data());
}