Commit Graph

18 Commits

Author SHA1 Message Date
topjohnwu
736729f5ef Maintain a list of pre-init mounts
Keep track of everything to unmount
2019-07-16 23:54:52 -07:00
topjohnwu
7ba8202af5 Introduce new root overlay system 2019-07-16 01:08:28 -07:00
topjohnwu
52fd508fea Do not use std::random_device
Directly read from urandom instead of using std::random_device.
libc++ will use iostream under-the-hood, which brings significant
binary size increase that is not welcomed, especially in magiskinit.
2019-07-14 21:56:21 -07:00
topjohnwu
41045b62dc Introduce more randomness
- Use C++ random generator instead of old and broken rand()
- Randomize string length to piss off stupid detectors
2019-07-14 17:42:49 -07:00
topjohnwu
7233285437 Use relative symbolic links 2019-07-04 17:58:46 -07:00
topjohnwu
05658cafc7 Fix typo causing sbin clone failure 2019-06-30 19:24:14 -07:00
topjohnwu
ff3710de66 Minor code changes across all sources 2019-06-30 19:09:31 -07:00
topjohnwu
db8dd9f186 Init code rearrangement 2019-06-30 11:39:13 -07:00
topjohnwu
e8b73ba6d1 Add separate product partition support 2019-06-29 14:19:10 -07:00
topjohnwu
f1112fdf37 Logical Resizable Android Partitions support
The way how logical partition, or "Logical Resizable Android Partitions"
as they say in AOSP source code, is setup makes it impossible to early
mount the partitions from the shared super partition with just
a few lines of code; in fact, AOSP has a whole "fs_mgr" folder which
consist of multiple complex libraries, with 15K lines of code just
to deal with the device mapper shenanigans.

In order to keep the already overly complicated MagiskInit more
managable, I chose NOT to go the route of including fs_mgr directly
into MagiskInit. Luckily, starting from Android Q, Google decided to
split init startup into 3 stages, with the first stage doing _only_
early mount. This is great news, because we can simply let the stock
init do its own thing for us, and we intercept the bootup sequence.

So the workflow can be visualized roughly below:

Magisk First Stage --> First Stage Mount --> Magisk Second Stage --+
   (MagiskInit)         (Original Init)         (MagiskInit)       +
                                                                   +
                                                                   +
     ...Rest of the boot... <-- Second Stage <-- Selinux Setup  <--+
      (__________________ Original Init ____________________)

The catch here is that after doing all the first stage mounting, /init
will pivot /system as root directory (/), leaving us impossible to
regain control after we hand it over. So the solution here is to patch
fstab in /first_stage_ramdisk on-the-fly to redirect /system to
/system_root, making the original init do all the hard work for
us and mount required early mount partitions, but skips the step of
switching root directory. It will also conveniently hand over execution
back to MagiskInit, which we will reuse the routine for patching
root directory in normal system-as-root situations.
2019-06-29 01:25:54 -07:00
topjohnwu
e29b712108 Start Magisk in SAR 2019-06-25 23:31:59 -07:00
topjohnwu
a462435f2f Load custom sepolicy 2019-06-25 21:34:02 -07:00
topjohnwu
911b8273fe Fix typo in sbin clone 2019-06-25 03:35:25 -07:00
topjohnwu
aac9e85e04 More Q cleanup 2019-06-25 02:38:34 -07:00
topjohnwu
bb67a837d3 Adjust class structures 2019-06-24 01:50:47 -07:00
topjohnwu
6cde695194 Remove Q dirty hacks in SARCompat 2019-06-24 01:31:42 -07:00
topjohnwu
a1a1ac0bbb Add sbin overlay to system-as-root 2019-06-24 01:21:33 -07:00
topjohnwu
9ec8bc2166 Boot MagiskInit as actual system-as-root
WIP, no customization. DO NOT USE YET!
2019-06-23 15:14:47 -07:00