Previous MagiskHide detects new app launches via listening through logcat
and filtering launch info messages.
This is extremely inefficient and prone to cause multiple issues both
theoratically and practically.
Rework this by using inotify to detect open() syscalls to target APKs.
This also solves issues related to Zygote-forked caching mechanisms such as
OnePlus OxygenOS' embryo.
Signed-off-by: Park Ju Hyung <qkrwngud825@gmail.com>
Mounting ext4 images causes tons of issues, such as unmountable with broken F2FS drivers.
Resizing is also very complicated and does not work properly on all devices.
Each step in either measuring free space, resizing, and shrinking the image is a
point of failure, and either step's failure could cause the module system completely broken.
The new method is to directly store modules into /data/adb/modules, and for module installation
on boot /data/adb/modules_update. Several compatibility layers has been done: the new path is
bind mounted to the old path (/sbin/.magisk/img), and the helper functions in util_functions.sh
will now transparently make existing modules install to the new location without any changes.
MagiskHide is also updated to unmount module files stored in this new location.
Services can name their process name arbitrarily, for instance the service in
com.google.android.gms that is responsible for SafetyNet is named
com.google.android.gms.unstable. There are many apps out in the wild use
dedicated services with special names to detect root, and previously the user
is expected to add all of them to the hide list.
In this commit, we change from targeting process names to component names.
On Android, component names are composed of <pkg>/<cls>. When targeting
component names, we can always know what application spawned the new process.
This means that if the user adds a package name to the hidelist, MagiskHide can
now target ALL possible processes of that specific application.
To abide with this change, the default SafetyNet target is now changed from
com.google.android.gms.unstable (process name) to
com.google.android.gms/.droidguard.DroidGuardService (component name)
The database should only be accessed by a single process, which is magiskd.
This means 'magisk --sqlite [SQL]' has to be updated to pass the SQL command to the daemon.
In addition, open the database connection with SQLITE_OPEN_FULLMUTEX to support multithread in magiskd.
In previous implementations, proc_monitor checks whether the mount namespace of an app is actually separated from zygote using a list generated at startup.
However, for some unknown reason, some devices (e.g. Samsung) has multiple zygote servers running in the background.
This means that app processes spawned from the unlisted zygotes are not checked whether the separation is done or not, causing MagiskHide unmount stuffs in the namespace of zygote, and since zygote is the "mother" of all apps, all apps will no longer have root access.
Since I'm not sure of the reason why multiple zygotes exists, so instead of checking the namespace against a list, compare the current namespace against the parent process's namespace.
This will make sure the namespace is NOT the same as the parent process, which is supposed to be the zygote server.
