mirror of
https://github.com/topjohnwu/Magisk.git
synced 2024-12-04 23:45:23 +00:00
003e44fb84
We used to construct /sbin tmpfs overlay in early-init stage after SELinux is properly initialized. However the way it is implemented (forking daemon from magiskinit with complicated file waiting triggers) is extremely complicated and error prone. This commit moves the construction of the sbin overlay to pre-init stage. The catch is that since SELinux is not present at that point, proper selabel has to be reconstructed afterwards. Some additional SEPolicy rules are added to make sure init can access magisk binaries, and the secontext relabeling task is assigned to the main Magisk daemon.
194 lines
4.1 KiB
C++
194 lines
4.1 KiB
C++
/* daemon.c - Magisk Daemon
|
|
*
|
|
* Start the daemon and wait for requests
|
|
* Connect the daemon and send requests through sockets
|
|
*/
|
|
|
|
#include <stdlib.h>
|
|
#include <unistd.h>
|
|
#include <fcntl.h>
|
|
#include <string.h>
|
|
#include <pthread.h>
|
|
#include <signal.h>
|
|
#include <sys/un.h>
|
|
#include <sys/types.h>
|
|
#include <sys/mount.h>
|
|
|
|
#include <magisk.h>
|
|
#include <utils.h>
|
|
#include <daemon.h>
|
|
#include <selinux.h>
|
|
#include <db.h>
|
|
#include <resetprop.h>
|
|
#include <flags.h>
|
|
|
|
int SDK_INT = -1;
|
|
bool RECOVERY_MODE = false;
|
|
static struct stat SERVER_STAT;
|
|
|
|
static void verify_client(int client, pid_t pid) {
|
|
// Verify caller is the same as server
|
|
char path[32];
|
|
sprintf(path, "/proc/%d/exe", pid);
|
|
struct stat st{};
|
|
stat(path, &st);
|
|
if (st.st_dev != SERVER_STAT.st_dev || st.st_ino != SERVER_STAT.st_ino) {
|
|
close(client);
|
|
pthread_exit(nullptr);
|
|
}
|
|
}
|
|
|
|
static void *request_handler(void *args) {
|
|
int client = *((int *) args);
|
|
delete (int *) args;
|
|
|
|
struct ucred credential;
|
|
get_client_cred(client, &credential);
|
|
if (credential.uid != 0)
|
|
verify_client(client, credential.pid);
|
|
|
|
int req = read_int(client);
|
|
switch (req) {
|
|
case MAGISKHIDE:
|
|
case POST_FS_DATA:
|
|
case LATE_START:
|
|
case BOOT_COMPLETE:
|
|
case SQLITE_CMD:
|
|
if (credential.uid != 0) {
|
|
write_int(client, ROOT_REQUIRED);
|
|
close(client);
|
|
return nullptr;
|
|
}
|
|
default:
|
|
break;
|
|
}
|
|
|
|
switch (req) {
|
|
case MAGISKHIDE:
|
|
magiskhide_handler(client);
|
|
break;
|
|
case SUPERUSER:
|
|
su_daemon_handler(client, &credential);
|
|
break;
|
|
case CHECK_VERSION:
|
|
write_string(client, MAGISK_VERSION ":MAGISK");
|
|
close(client);
|
|
break;
|
|
case CHECK_VERSION_CODE:
|
|
write_int(client, MAGISK_VER_CODE);
|
|
close(client);
|
|
break;
|
|
case POST_FS_DATA:
|
|
post_fs_data(client);
|
|
break;
|
|
case LATE_START:
|
|
late_start(client);
|
|
break;
|
|
case BOOT_COMPLETE:
|
|
boot_complete(client);
|
|
break;
|
|
case SQLITE_CMD:
|
|
exec_sql(client);
|
|
break;
|
|
default:
|
|
close(client);
|
|
break;
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
static void main_daemon() {
|
|
android_logging();
|
|
setsid();
|
|
setcon("u:r:" SEPOL_PROC_DOMAIN ":s0");
|
|
restore_rootcon();
|
|
|
|
int fd = xopen("/dev/null", O_RDWR | O_CLOEXEC);
|
|
xdup2(fd, STDOUT_FILENO);
|
|
xdup2(fd, STDERR_FILENO);
|
|
close(fd);
|
|
fd = xopen("/dev/zero", O_RDWR | O_CLOEXEC);
|
|
xdup2(fd, STDIN_FILENO);
|
|
close(fd);
|
|
|
|
LOGI(SHOW_VER(Magisk) " daemon started\n");
|
|
|
|
// Get server stat
|
|
stat("/proc/self/exe", &SERVER_STAT);
|
|
|
|
// Get API level
|
|
parse_prop_file("/system/build.prop", [](auto key, auto val) -> bool {
|
|
if (key == "ro.build.version.sdk") {
|
|
LOGI("* Device API level: %s\n", val.data());
|
|
SDK_INT = parse_int(val);
|
|
return false;
|
|
}
|
|
return true;
|
|
});
|
|
|
|
// Load config status
|
|
parse_prop_file(MAGISKTMP "/config", [](auto key, auto val) -> bool {
|
|
if (key == "RECOVERYMODE" && val == "true")
|
|
RECOVERY_MODE = true;
|
|
return true;
|
|
});
|
|
|
|
struct sockaddr_un sun;
|
|
socklen_t len = setup_sockaddr(&sun, MAIN_SOCKET);
|
|
fd = xsocket(AF_LOCAL, SOCK_STREAM | SOCK_CLOEXEC, 0);
|
|
if (xbind(fd, (struct sockaddr*) &sun, len))
|
|
exit(1);
|
|
xlisten(fd, 10);
|
|
|
|
// Change process name
|
|
set_nice_name("magiskd");
|
|
|
|
// Block all signals
|
|
sigset_t block_set;
|
|
sigfillset(&block_set);
|
|
pthread_sigmask(SIG_SETMASK, &block_set, nullptr);
|
|
|
|
// Loop forever to listen for requests
|
|
for (;;) {
|
|
int *client = new int;
|
|
*client = xaccept4(fd, nullptr, nullptr, SOCK_CLOEXEC);
|
|
new_daemon_thread(request_handler, client);
|
|
}
|
|
}
|
|
|
|
int switch_mnt_ns(int pid) {
|
|
char mnt[32];
|
|
snprintf(mnt, sizeof(mnt), "/proc/%d/ns/mnt", pid);
|
|
if (access(mnt, R_OK) == -1) return 1; // Maybe process died..
|
|
|
|
int fd, ret;
|
|
fd = xopen(mnt, O_RDONLY);
|
|
if (fd < 0) return 1;
|
|
// Switch to its namespace
|
|
ret = xsetns(fd, 0);
|
|
close(fd);
|
|
return ret;
|
|
}
|
|
|
|
int connect_daemon(bool create) {
|
|
struct sockaddr_un sun;
|
|
socklen_t len = setup_sockaddr(&sun, MAIN_SOCKET);
|
|
int fd = xsocket(AF_LOCAL, SOCK_STREAM | SOCK_CLOEXEC, 0);
|
|
if (connect(fd, (struct sockaddr*) &sun, len)) {
|
|
if (!create || getuid() != UID_ROOT || getgid() != UID_ROOT) {
|
|
LOGE("No daemon is currently running!\n");
|
|
exit(1);
|
|
}
|
|
|
|
LOGD("client: launching new main daemon process\n");
|
|
if (fork_dont_care() == 0) {
|
|
close(fd);
|
|
main_daemon();
|
|
}
|
|
|
|
while (connect(fd, (struct sockaddr*) &sun, len))
|
|
usleep(10000);
|
|
}
|
|
return fd;
|
|
}
|