Magisk/native/jni/core/restorecon.cpp
2020-04-11 04:40:40 -07:00

101 lines
2.5 KiB
C++

#include <string_view>
#include <magisk.hpp>
#include <selinux.hpp>
#include <utils.hpp>
using namespace std;
#define UNLABEL_CON "u:object_r:unlabeled:s0"
#define SYSTEM_CON "u:object_r:system_file:s0"
#define ADB_CON "u:object_r:adb_data_file:s0"
#define ROOT_CON "u:object_r:rootfs:s0"
#define MAGISK_CON "u:object_r:" SEPOL_FILE_DOMAIN ":s0"
static void restore_syscon(int dirfd) {
struct dirent *entry;
DIR *dir;
char *con;
fgetfilecon(dirfd, &con);
if (strlen(con) == 0 || strcmp(con, UNLABEL_CON) == 0)
fsetfilecon(dirfd, SYSTEM_CON);
freecon(con);
dir = xfdopendir(dirfd);
while ((entry = xreaddir(dir))) {
if (entry->d_name == "."sv || entry->d_name == ".."sv)
continue;
int fd = openat(dirfd, entry->d_name, O_RDONLY | O_CLOEXEC);
if (entry->d_type == DT_DIR) {
restore_syscon(fd);
} else if (entry->d_type == DT_REG) {
fgetfilecon(fd, &con);
if (con[0] == '\0' || strcmp(con, UNLABEL_CON) == 0)
fsetfilecon(fd, SYSTEM_CON);
freecon(con);
} else if (entry->d_type == DT_LNK) {
getfilecon_at(dirfd, entry->d_name, &con);
if (con[0] == '\0' || strcmp(con, UNLABEL_CON) == 0)
setfilecon_at(dirfd, entry->d_name, con);
freecon(con);
}
close(fd);
}
}
static void restore_magiskcon(int dirfd) {
struct dirent *entry;
DIR *dir;
fsetfilecon(dirfd, MAGISK_CON);
fchown(dirfd, 0, 0);
dir = xfdopendir(dirfd);
while ((entry = xreaddir(dir))) {
if (entry->d_name == "."sv || entry->d_name == ".."sv)
continue;
int fd = xopenat(dirfd, entry->d_name, O_RDONLY | O_CLOEXEC);
if (entry->d_type == DT_DIR) {
restore_magiskcon(fd);
} else if (entry->d_type) {
fsetfilecon(fd, MAGISK_CON);
fchown(fd, 0, 0);
}
close(fd);
}
}
void restorecon() {
int fd = xopen(SELINUX_CONTEXT, O_WRONLY | O_CLOEXEC);
if (write(fd, ADB_CON, sizeof(ADB_CON)) >= 0)
lsetfilecon(SECURE_DIR, ADB_CON);
close(fd);
lsetfilecon(MODULEROOT, SYSTEM_CON);
fd = xopen(MODULEROOT, O_RDONLY | O_CLOEXEC);
restore_syscon(fd);
close(fd);
fd = xopen(DATABIN, O_RDONLY | O_CLOEXEC);
restore_magiskcon(fd);
close(fd);
}
void restore_rootcon() {
setfilecon("/sbin", ROOT_CON);
setfilecon(MAGISKTMP, ROOT_CON);
setfilecon(MIRRDIR, ROOT_CON);
setfilecon(BLOCKDIR, ROOT_CON);
auto dir = xopen_dir("/sbin");
int dfd = dirfd(dir.get());
for (dirent *entry; (entry = xreaddir(dir.get()));) {
if (entry->d_name == "."sv || entry->d_name == ".."sv)
continue;
setfilecon_at(dfd, entry->d_name, ROOT_CON);
}
setfilecon("/sbin/magisk", MAGISK_CON);
setfilecon("/sbin/magiskinit", MAGISK_CON);
}