andreacavalli/Magisk
1
0
Fork 0
forked from MarcoBuster/Magisk
Code Issues Pull Requests Projects Releases Wiki Activity

Separate SAR and legacy implementation

Browse Source
This commit is contained in:
topjohnwu 2019-06-16 12:45:32 -07:00
parent f1d9015e5f
commit 5c7f69acaa
4 changed files with 140 additions and 107 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

76
native/jni/init/early_mount.cpp
View File

@ -5,6 +5,7 @@
#include <utils.h>
#include <logging.h>
#include <selinux.h>
#include "init.h"
@ -73,7 +74,7 @@ static void setup_block(const char *partname, char *block_dev) {
}
}
bool MagiskInit::read_dt_fstab(const char *name, char *partname, char *fstype) {
bool BaseInit::read_dt_fstab(const char *name, char *partname, char *fstype) {
char path[128];
int fd;
sprintf(path, "%s/fstab/%s/dev", cmd->dt_dir, name);
@ -106,38 +107,57 @@ if (!is_lnk("/" #name) && read_dt_fstab(#name, partname, fstype)) { \
mnt_##name = true; \
}
void MagiskInit::early_mount() {
void LegacyInit::early_mount() {
char partname[32];
char fstype[32];
char block_dev[64];
if (cmd->system_as_root) {
LOGD("Early mount system_root\n");
sprintf(partname, "system%s", cmd->slot);
setup_block(partname, block_dev);
xmkdir("/system_root", 0755);
if (xmount(block_dev, "/system_root", "ext4", MS_RDONLY, nullptr))
xmount(block_dev, "/system_root", "erofs", MS_RDONLY, nullptr);
xmkdir("/system", 0755);
xmount("/system_root/system", "/system", nullptr, MS_BIND, nullptr);
// Android Q
if (is_lnk("/system_root/init"))
load_sepol = true;
// System-as-root with monolithic sepolicy
if (access("/system_root/sepolicy", F_OK) == 0)
cp_afc("/system_root/sepolicy", "/sepolicy");
// Copy if these partitions are symlinks
link_root("/vendor");
link_root("/product");
link_root("/odm");
} else {
mount_root(system);
}
mount_root(system);
mount_root(vendor);
mount_root(product);
mount_root(odm);
}
void SARInit::early_mount() {
char partname[32];
char fstype[32];
char block_dev[64];
LOGD("Early mount system_root\n");
sprintf(partname, "system%s", cmd->slot);
setup_block(partname, block_dev);
xmkdir("/system_root", 0755);
if (xmount(block_dev, "/system_root", "ext4", MS_RDONLY, nullptr))
xmount(block_dev, "/system_root", "erofs", MS_RDONLY, nullptr);
xmkdir("/system", 0755);
xmount("/system_root/system", "/system", nullptr, MS_BIND, nullptr);
// Android Q
if (is_lnk("/system_root/init"))
load_sepol = true;
// System-as-root with monolithic sepolicy
if (access("/system_root/sepolicy", F_OK) == 0)
cp_afc("/system_root/sepolicy", "/sepolicy");
link_root("/vendor");
link_root("/product");
link_root("/odm");
mount_root(vendor);
mount_root(product);
mount_root(odm);
}
#define umount_root(name) \
if (mnt_##name) \
umount("/" #name);
void BaseInit::cleanup() {
umount(SELINUX_MNT);
umount("/sys");
umount("/proc");
umount_root(system);
umount_root(vendor);
umount_root(product);
umount_root(odm);
}

135
native/jni/init/init.cpp
View File

@ -6,13 +6,11 @@
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <dirent.h>
#include <fcntl.h>
#include <libgen.h>
#include <xz.h>
#include <magisk.h>
#include <selinux.h>
#include <cpio.h>
#include <utils.h>
#include <flags.h>
@ -48,12 +46,10 @@ static void setup_klog() {
#define setup_klog(...)
#endif
static int test_main(int argc, char *argv[]);
constexpr const char *init_applet[] =
{ "magiskpolicy", "supolicy", "init_test", nullptr };
{ "magiskpolicy", "supolicy", nullptr };
constexpr int (*init_applet_main[])(int, char *[]) =
{ magiskpolicy_main, magiskpolicy_main, test_main, nullptr };
{ magiskpolicy_main, magiskpolicy_main, nullptr };
static bool unxz(int fd, const uint8_t *buf, size_t size) {
uint8_t out[8192];
@ -117,50 +113,27 @@ static int dump_manager(const char *path, mode_t mode) {
return 0;
}
void MagiskInit::preset() {
root = open("/", O_RDONLY | O_CLOEXEC);
if (cmd->system_as_root) {
// Clear rootfs
LOGD("Cleaning rootfs\n");
frm_rf(root, { "overlay", "proc", "sys" });
} else {
decompress_ramdisk();
// Revert original init binary
rename("/.backup/init", "/init");
rm_rf("/.backup");
// Do not go further if device is booting into recovery
if (access("/sbin/recovery", F_OK) == 0) {
LOGD("Ramdisk is recovery, abort\n");
re_exec_init();
}
}
}
#define umount_root(name) \
if (mnt_##name) \
umount("/" #name);
void MagiskInit::cleanup() {
umount(SELINUX_MNT);
umount("/sys");
umount("/proc");
umount_root(system);
umount_root(vendor);
umount_root(product);
umount_root(odm);
}
void MagiskInit::re_exec_init() {
void BaseInit::re_exec_init() {
LOGD("Re-exec /init\n");
cleanup();
execv("/init", argv);
exit(1);
}
void MagiskInit::start() {
void LegacyInit::preset() {
LOGD("Reverting /init\n");
root = open("/", O_RDONLY | O_CLOEXEC);
rename("/.backup/init", "/init");
rm_rf("/.backup");
}
void SARInit::preset() {
LOGD("Cleaning rootfs\n");
root = open("/", O_RDONLY | O_CLOEXEC);
frm_rf(root, { "overlay", "proc", "sys" });
}
void BaseInit::start() {
// Prevent file descriptor confusion
mknod("/null", S_IFCHR | 0666, makedev(1, 3));
int null = open("/null", O_RDWR | O_CLOEXEC);
@ -180,27 +153,27 @@ void MagiskInit::start() {
re_exec_init();
}
void MagiskInit::test() {
cmdline_logging();
log_cb.ex = nop_ex;
class RecoveryInit : public BaseInit {
public:
RecoveryInit(char *argv[], cmdline *cmd) : BaseInit(argv, cmd) {};
void start() override {
LOGD("Ramdisk is recovery, abort\n");
rename("/.backup/init", "/init");
rm_rf("/.backup");
re_exec_init();
}
};
chdir(dirname(argv[0]));
chroot(".");
chdir("/");
preset();
early_mount();
setup_rootfs();
cleanup();
}
static int test_main(int, char *argv[]) {
cmdline cmd{};
load_kernel_info(&cmd);
MagiskInit init(argv, &cmd);
init.test();
return 0;
}
class TestInit : public SARInit {
public:
TestInit(char *argv[], cmdline *cmd) : SARInit(argv, cmd) {};
void start() override {
preset();
early_mount();
setup_rootfs();
cleanup();
}
};
int main(int argc, char *argv[]) {
umask(0);
@ -217,16 +190,40 @@ int main(int argc, char *argv[]) {
return dump_manager(argv[3], 0644);
}
if (getpid() != 1)
return 1;
#ifdef MAGISK_DEBUG
bool run_test = getenv("INIT_TEST") != nullptr;
#else
constexpr bool run_test = false;
#endif
setup_klog();
if (run_test) {
chdir(dirname(argv[0]));
chroot(".");
chdir("/");
cmdline_logging();
log_cb.ex = nop_ex;
} else {
if (getpid() != 1)
return 1;
setup_klog();
}
cmdline cmd{};
load_kernel_info(&cmd);
MagiskInit init(argv, &cmd);
unique_ptr<BaseInit> init;
if (run_test) {
init = make_unique<TestInit>(argv, &cmd);
} else if (cmd.system_as_root) {
init = make_unique<SARInit>(argv, &cmd);
} else {
decompress_ramdisk();
if (access("/sbin/recovery", F_OK) == 0)
init = make_unique<RecoveryInit>(argv, &cmd);
else
init = make_unique<LegacyInit>(argv, &cmd);
}
// Run the main routine
init.start();
init->start();
}

32
native/jni/init/init.h
View File

@ -11,21 +11,21 @@ struct raw_data {
size_t sz;
};
class MagiskInit {
private:
class BaseInit {
protected:
cmdline *cmd;
raw_data self{};
raw_data config{};
int root = -1;
char **argv;
int root = -1;
bool load_sepol = false;
bool mnt_system = false;
bool mnt_vendor = false;
bool mnt_product = false;
bool mnt_odm = false;
void preset();
void early_mount();
virtual void preset() {};
virtual void early_mount() {}
void setup_rootfs();
bool read_dt_fstab(const char *name, char *partname, char *fstype);
bool patch_sepolicy();
@ -33,9 +33,25 @@ private:
void re_exec_init();
public:
explicit MagiskInit(char *argv[], cmdline *cmd) : cmd(cmd), argv(argv) {}
void start();
void test();
BaseInit(char *argv[], cmdline *cmd) : cmd(cmd), argv(argv) {}
virtual ~BaseInit() = default;
virtual void start();
};
class LegacyInit : public BaseInit {
protected:
void preset() override;
void early_mount() override;
public:
LegacyInit(char *argv[], cmdline *cmd) : BaseInit(argv, cmd) {};
};
class SARInit : public BaseInit {
protected:
void preset() override;
void early_mount() override;
public:
SARInit(char *argv[], cmdline *cmd) : BaseInit(argv, cmd) {};
};
static inline bool is_lnk(const char *name) {

4
native/jni/init/rootfs.cpp
View File

@ -37,7 +37,7 @@ constexpr const char wrapper[] =
"exec /sbin/magisk.bin \"$0\" \"$@\"\n"
;
void MagiskInit::setup_rootfs() {
void BaseInit::setup_rootfs() {
bool patch_init = patch_sepolicy();
if (cmd->system_as_root) {
@ -173,7 +173,7 @@ void MagiskInit::setup_rootfs() {
close(sbin);
}
bool MagiskInit::patch_sepolicy() {
bool BaseInit::patch_sepolicy() {
bool patch_init = false;
if (access(SPLIT_PLAT_CIL, R_OK) == 0) {