TheArchive/Magisk
1
0
Fork 0
mirror of https://github.com/topjohnwu/Magisk.git synced 2025-12-03 09:21:57 +00:00
Code Issues Packages Projects Releases Wiki Activity

Add sbin overlay to system-as-root

Browse Source
This commit is contained in:
topjohnwu
2019-06-24 01:21:33 -07:00
parent 9ec8bc2166
commit a1a1ac0bbb
6 changed files with 100 additions and 40 deletions
Download Patch File Download Diff File Expand all files Collapse all files

115
native/jni/init/rootdir.cpp
View File

@@ -175,6 +175,84 @@ bool MagiskInit::patch_sepolicy() {
return patch_init;
}
static void sbin_overlay(const raw_data &self, const raw_data &config) {
LOGD("Mount /sbin tmpfs overlay\n");
xmount("tmpfs", "/sbin", "tmpfs", 0, "mode=755");
// Dump binaries
xmkdir(MAGISKTMP, 0755);
int fd = xopen(MAGISKTMP "/config", O_WRONLY | O_CREAT, 0000);
xwrite(fd, config.buf, config.sz);
close(fd);
fd = xopen("/sbin/magiskinit", O_WRONLY | O_CREAT, 0755);
xwrite(fd, self.buf, self.sz);
close(fd);
if (access("/system/apex", F_OK) == 0) {
LOGD("APEX detected, use wrapper\n");
dump_magisk("/sbin/magisk.bin", 0755);
patch_socket_name("/sbin/magisk.bin");
fd = xopen("/sbin/magisk", O_WRONLY | O_CREAT, 0755);
xwrite(fd, wrapper, sizeof(wrapper) - 1);
close(fd);
} else {
dump_magisk("/sbin/magisk", 0755);
patch_socket_name("/sbin/magisk");
}
// Create applet symlinks
char path[64];
for (int i = 0; applet_names[i]; ++i) {
sprintf(path, "/sbin/%s", applet_names[i]);
xsymlink("/sbin/magisk", path);
}
xsymlink("/sbin/magiskinit", "/sbin/magiskpolicy");
xsymlink("/sbin/magiskinit", "/sbin/supolicy");
}
#define ROOTMIR MIRRDIR "/system_root"
#define ROOTBLK BLOCKDIR "/system_root"
void SARInit::patch_rootdir() {
sbin_overlay(self, config);
// Mount system_root mirror
xmkdir(MIRRDIR, 0777);
xmkdir(ROOTMIR, 0777);
xmkdir(BLOCKDIR, 0777);
mknod(ROOTBLK, S_IFBLK | 0600, system_dev);
if (xmount(ROOTBLK, ROOTMIR, "ext4", MS_RDONLY, nullptr))
xmount(ROOTBLK, ROOTMIR, "erofs", MS_RDONLY, nullptr);
// Recreate original sbin structure
int src = xopen(ROOTMIR, O_RDONLY | O_CLOEXEC);
int dest = xopen(ROOTMIR, O_RDONLY | O_CLOEXEC);
DIR *fp = fdopendir(src);
struct dirent *entry;
struct stat st;
char buf[256];
while ((entry = xreaddir(fp))) {
if (entry->d_name == "."sv || entry->d_name == ".."sv)
continue;
fstatat(src, entry->d_name, &st, AT_SYMLINK_NOFOLLOW);
if (S_ISLNK(st.st_mode)) {
xreadlinkat(src, entry->d_name, buf, sizeof(buf));
xsymlinkat(buf, dest, entry->d_name);
} else {
char tpath[256];
sprintf(buf, "/sbin/%s", entry->d_name);
sprintf(tpath, ROOTMIR "/sbin/%s", entry->d_name);
// Create dummy
if (S_ISDIR(st.st_mode))
xmkdir(tpath, st.st_mode & 0777);
else
close(xopen(tpath, O_CREAT | O_WRONLY | O_CLOEXEC, st.st_mode & 0777));
xmount(tpath, buf, nullptr, MS_BIND, nullptr);
}
}
close(src);
close(dest);
}
#ifdef MAGISK_DEBUG
static FILE *kmsg;
static int vprintk(const char *fmt, va_list ap) {
@@ -206,14 +284,12 @@ int magisk_proxy_main(int argc, char *argv[]) {
unlink("/sbin/magisk");
rm_rf("/.backup");
LOGD("Mount /sbin tmpfs overlay\n");
xmount("tmpfs", "/sbin", "tmpfs", 0, "mode=755");
int sbin = xopen("/sbin", O_RDONLY | O_CLOEXEC);
char path[64];
sbin_overlay(self, config);
// Create symlinks pointing back to /root
{
char path[256];
int sbin = xopen("/sbin", O_RDONLY | O_CLOEXEC);
unique_ptr<DIR, decltype(&closedir)> dir(xopendir("/root"), &closedir);
struct dirent *entry;
while((entry = xreaddir(dir.get()))) {
@@ -222,36 +298,9 @@ int magisk_proxy_main(int argc, char *argv[]) {
sprintf(path, "/root/%s", entry->d_name);
xsymlinkat(path, sbin, entry->d_name);
}
close(sbin);
}
// Dump binaries
mkdir(MAGISKTMP, 0755);
int fd = xopen(MAGISKTMP "/config", O_WRONLY | O_CREAT, 0000);
write(fd, config.buf, config.sz);
close(fd);
fd = xopen("/sbin/magiskinit", O_WRONLY | O_CREAT, 0755);
write(fd, self.buf, self.sz);
close(fd);
if (access("/system/apex", F_OK) == 0) {
LOGD("APEX detected, use wrapper\n");
dump_magisk("/sbin/magisk.bin", 0755);
patch_socket_name("/sbin/magisk.bin");
fd = xopen("/sbin/magisk", O_WRONLY | O_CREAT, 0755);
write(fd, wrapper, sizeof(wrapper) - 1);
close(fd);
} else {
dump_magisk("/sbin/magisk", 0755);
patch_socket_name("/sbin/magisk");
}
// Create applet symlinks
for (int i = 0; applet_names[i]; ++i) {
sprintf(path, "/sbin/%s", applet_names[i]);
xsymlink("/sbin/magisk", path);
}
xsymlink("/sbin/magiskinit", "/sbin/magiskpolicy");
xsymlink("/sbin/magiskinit", "/sbin/supolicy");
setenv("REMOUNT_ROOT", "1", 1);
execv("/sbin/magisk", argv);