Magisk/native/jni/magiskhide/hide_utils.cpp
2019-03-23 04:39:34 -04:00

332 lines
7.2 KiB
C++

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mount.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <dirent.h>
#include <string.h>
#include <libgen.h>
#include <magisk.h>
#include <utils.h>
#include <resetprop.h>
#include <db.h>
#include <selinux.h>
#include "magiskhide.h"
using namespace std;
static pthread_t proc_monitor_thread;
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 manage_selinux() {
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);
}
}
static void hide_sensitive_props() {
LOGI("hide_utils: 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);
}
}
// Leave /proc fd opened as we're going to read from it repeatedly
static DIR *procfp;
void crawl_procfs(const function<bool (int)> &fn) {
rewinddir(procfp);
crawl_procfs(procfp, fn);
}
void crawl_procfs(DIR *dir, const function<bool (int)> &fn) {
struct dirent *dp;
int pid;
while ((dp = readdir(dir))) {
pid = parse_int(dp->d_name);
if (pid > 0 && !fn(pid))
break;
}
}
bool proc_name_match(int pid, const char *name) {
char buf[4019];
FILE *f;
#if 0
sprintf(buf, "/proc/%d/comm", pid);
if ((f = fopen(buf, "re"))) {
fgets(buf, sizeof(buf), f);
fclose(f);
if (strcmp(buf, name) == 0)
return true;
} else {
// The PID is already killed
return false;
}
#endif
sprintf(buf, "/proc/%d/cmdline", pid);
if ((f = fopen(buf, "re"))) {
fgets(buf, sizeof(buf), f);
fclose(f);
if (strcmp(basename(buf), name) == 0)
return true;
}
return false;
#if 0
sprintf(buf, "/proc/%d/exe", pid);
ssize_t len;
if ((len = readlink(buf, buf, sizeof(buf))) < 0)
return false;
buf[len] = '\0';
return strcmp(basename(buf), name) == 0;
#endif
}
static void kill_process(const char *name) {
crawl_procfs([=](int pid) -> bool {
if (proc_name_match(pid, name)) {
if (kill(pid, SIGTERM) == 0)
LOGD("hide_utils: killed PID=[%d] (%s)\n", pid, name);
return false;
}
return true;
});
}
void clean_magisk_props() {
getprop([](const char *name, auto, auto) -> void {
if (strstr(name, "magisk"))
deleteprop(name);
}, nullptr, false);
}
static int add_list(const char *pkg, const char *proc = "") {
if (proc[0] == '\0')
proc = pkg;
for (auto &hide : hide_set)
if (hide.first == pkg && hide.second == proc)
return HIDE_ITEM_EXIST;
// Add to database
char sql[4096];
snprintf(sql, sizeof(sql),
"INSERT INTO hidelist (package_name, process) VALUES('%s', '%s')", pkg, proc);
char *err = db_exec(sql);
db_err_cmd(err, return DAEMON_ERROR);
LOGI("hide_list add: [%s/%s]\n", pkg, proc);
// Critical region
{
MutexGuard lock(monitor_lock);
hide_set.emplace(pkg, proc);
}
kill_process(proc);
return DAEMON_SUCCESS;
}
int add_list(int client) {
char *pkg = read_string(client);
char *proc = read_string(client);
int ret = add_list(pkg, proc);
free(pkg);
free(proc);
update_uid_map();
return ret;
}
static int rm_list(const char *pkg, const char *proc = "") {
{
// Critical region
MutexGuard lock(monitor_lock);
bool remove = false;
auto next = hide_set.begin();
decltype(next) cur;
while (next != hide_set.end()) {
cur = next;
++next;
if (cur->first == pkg && (proc[0] == '\0' || cur->second == proc)) {
remove = true;
LOGI("hide_list rm: [%s]\n", cur->second.data());
hide_set.erase(cur);
}
}
if (!remove)
return HIDE_ITEM_NOT_EXIST;
}
char sql[4096];
if (proc[0] == '\0')
snprintf(sql, sizeof(sql), "DELETE FROM hidelist WHERE package_name='%s'", pkg);
else
snprintf(sql, sizeof(sql),
"DELETE FROM hidelist WHERE package_name='%s' AND process='%s'", pkg, proc);
char *err = db_exec(sql);
db_err(err);
return DAEMON_SUCCESS;
}
int rm_list(int client) {
char *pkg = read_string(client);
char *proc = read_string(client);
int ret = rm_list(pkg, proc);
free(pkg);
free(proc);
if (ret == DAEMON_SUCCESS)
update_uid_map();
return ret;
}
static void init_list(const char *pkg, const char *proc) {
LOGI("hide_list init: [%s/%s]\n", pkg, proc);
hide_set.emplace(pkg, proc);
kill_process(proc);
}
#define LEGACY_LIST MODULEROOT "/.core/hidelist"
bool init_list() {
LOGD("hide_list: initialize\n");
char *err = db_exec("SELECT * FROM hidelist", [](db_row &row) -> bool {
init_list(row["package_name"].data(), row["process"].data());
return true;
});
db_err_cmd(err, return false);
// Migrate old hide list into database
if (access(LEGACY_LIST, R_OK) == 0) {
file_readline(LEGACY_LIST, [](string_view s) -> bool {
add_list(s.data());
return true;
});
unlink(LEGACY_LIST);
}
// Add SafetyNet by default
rm_list(SAFETYNET_COMPONENT);
rm_list(SAFETYNET_PROCESS);
init_list(SAFETYNET_PKG, SAFETYNET_PKG);
init_list(SAFETYNET_PKG, SAFETYNET_PROCESS);
init_list(MICROG_SAFETYNET, SAFETYNET_PROCESS);
update_uid_map();
return true;
}
void ls_list(int client) {
FILE *out = fdopen(recv_fd(client), "a");
for (auto &hide : hide_set)
fprintf(out, "%s|%s\n", hide.first.data(), hide.second.data());
fclose(out);
write_int(client, DAEMON_SUCCESS);
close(client);
}
static void set_hide_config() {
char sql[64];
sprintf(sql, "REPLACE INTO settings (key,value) VALUES('%s',%d)",
DB_SETTING_KEYS[HIDE_CONFIG], hide_enabled);
char *err = db_exec(sql);
db_err(err);
}
static inline void launch_err(int client, int code = DAEMON_ERROR) {
if (code != HIDE_IS_ENABLED)
hide_enabled = false;
if (client >= 0) {
write_int(client, code);
close(client);
}
pthread_exit(nullptr);
}
#define LAUNCH_ERR launch_err(client)
void launch_magiskhide(int client) {
if (SDK_INT < 19)
LAUNCH_ERR;
if (hide_enabled)
launch_err(client, HIDE_IS_ENABLED);
if (access("/proc/1/ns/mnt", F_OK) != 0)
launch_err(client, HIDE_NO_NS);
hide_enabled = true;
set_hide_config();
LOGI("* Starting MagiskHide\n");
if (procfp == nullptr && (procfp = opendir("/proc")) == nullptr)
LAUNCH_ERR;
hide_sensitive_props();
// Initialize the mutex lock
pthread_mutex_init(&monitor_lock, nullptr);
// Initialize the hide list
if (!init_list())
LAUNCH_ERR;
// Get thread reference
proc_monitor_thread = pthread_self();
if (client >= 0) {
write_int(client, DAEMON_SUCCESS);
close(client);
client = -1;
}
// Start monitoring
proc_monitor();
// proc_monitor should not return
LAUNCH_ERR;
}
int stop_magiskhide() {
LOGI("* Stopping MagiskHide\n");
hide_enabled = false;
set_hide_config();
pthread_kill(proc_monitor_thread, SIGTERMTHRD);
return DAEMON_SUCCESS;
}
void auto_start_magiskhide() {
db_settings dbs;
get_db_settings(dbs, HIDE_CONFIG);
if (dbs[HIDE_CONFIG]) {
new_daemon_thread([](auto) -> void* {
launch_magiskhide(-1);
return nullptr;
});
}
}