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docs/README.MD

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 # Magisk Documentations
-#### (Updated on 2017.8.14 for Magisk v13.5+)
+#### (Updated on 2017.8.15 for Magisk v13.5+)
 
 - Magisk Details
-    - **(Important!)** [Full Procedures](https://cdn.rawgit.com/topjohnwu/Magisk/e1023fdfafb038956367fce582db1726f50a878f/docs/procedures.html)
+    - [Introduction](#introduction)
+    - **(Important!)** [Procedure Diagram](https://cdn.rawgit.com/topjohnwu/Magisk/e1023fdfafb038956367fce582db1726f50a878f/docs/procedures.html)
+    - [Available Applets](applets.md)
+        - [magisk](applets.md#magisk)
+        - [su](applets.md#su)
+        - [resetprop](applets.md#resetprop)
+        - [magiskpolicy](applets.md#magiskpolicy)
+        - [magiskhide](applets.md#magiskhide)
 - [Modules and Repos](module_repo.md)
     - [Modules and Templates](module_repo.md#magisk-module-format)
     - [Submit Modules to Repo](module_repo.md#submit-your-module-to-magisk-modules-repo)
+
+    
+## Introduction
+Magisk is a suite of open source tools for devices running Android version higher than 5.0 Lollipop (API 21). It provides an environment which covers most Android aftermarket customization like root, boot scripts, SELinux patches, and also acts as a **Systemless Interface** to alter the system (or vendor) arbitrarily while the actual partitions stay completely intact, all of which accomplished by only patching the boot image, and adding some files into `/data`.
+
+## Document Changelog
+- 2017.8.15
+    - Initial version
+
+

docs/applets.md

@@ -0,0 +1,179 @@
+## Available Applets
+Magisk has a core binary which acts as a multi-call program with many applets. Here is an introduction to all available applets.
+
+### magisk
+The magisk binary provides a lot of utility functions used in both Magisk installation and also module installation. It is also the entry point for `init` to invoke magisk's boot procedures.
+
+Command help message:
+
+```
+Usage: magisk [applet [arguments]...]
+   or: magisk --install [SOURCE] DIR
+       if SOURCE not provided, will link itself
+   or: magisk --list
+   or: magisk --createimg IMG SIZE
+       create ext4 image, SIZE is interpreted in MB
+   or: magisk --imgsize IMG
+   or: magisk --resizeimg IMG SIZE
+       SIZE is interpreted in MB
+   or: magisk --mountimg IMG PATH
+       mount IMG to PATH and prints the loop device
+   or: magisk --umountimg PATH LOOP
+   or: magisk --[boot stage]
+       start boot stage service
+   or: magisk [options]
+   or: applet [arguments]...
+
+Supported boot stages:
+   post-fs, post-fs-data, service
+
+Options:
+   -c          print client version
+   -v          print daemon version
+   -V          print daemon version code
+
+Supported applets:
+    su, resetprop, magiskpolicy, supolicy, sepolicy-inject, magiskhide
+```
+
+### su
+The MagiskSU entrypoint. Call `su` to gain a root shell. **MagiskSU** has done several optimizations, check them out in the procedure diagram.
+
+Command help message:
+
+```
+Usage: su [options] [--] [-] [LOGIN] [--] [args...]
+
+Options:
+  -c, --command COMMAND         pass COMMAND to the invoked shell
+  -h, --help                    display this help message and exit
+  -, -l, --login                pretend the shell to be a login shell
+  -m, -p,
+  --preserve-environment        do not change environment variables
+  -s, --shell SHELL             use SHELL instead of the default /system/bin/sh
+  -u                            display the multiuser mode and exit
+  -v, --version                 display version number and exit
+  -V                            display version code and exit,
+                                this is used almost exclusively by Superuser.apk
+  -mm, -M,
+  --mount-master                run in the global mount namespace,
+                                use if you need to publicly apply mounts
+```
+
+Note: the `-Z --context` option still exists, but the option will do nothing since it's not needed anymore. It's still there because some apps requires specific context to work properly on legacy root implementations, and I don't want them to break.
+
+### resetprop
+An advanced system prop manipulation utility; using this tool, you can arbitrarily alter system props. Here's some background knowledge:
+
+> System props are stored in a hybrid trie/binary tree data structure; it is originally designed to only support adding nodes, and no nodes will be removed. Props can be read by many processes (e.g. via the `getprop` command); however, only the `init` process can write to the data. `init` provides a `property_service` to accept property update requests, so all property changes are monitored and controlled by `init`. The restrictions of **read-only** props (props that starts with `ro.`), which they can only be set once and cannot be changed afterwards, is therefore implemented in `init`.
+
+**resetprop** mimics what `init` is doing: directly accessing the data structure. This bypasses the whole `property_service` part, so we gain **arbitrary modification** power. Deleting properties, which was stated *"forbidden"* in the data structure is also implemented in resetprop through some tricks.
+
+One subtle thing to be aware of is that if we change props by directly modifying the data structure, `on property:foo=bar` triggers registered in `*.rc` scripts will not be triggered properly. This may be a good thing or a bad thing, depending on what result you want. I made the default behavior to match the original setprop command, which **will** trigger events, but still I provide a flag to disable it if you needed it.
+
+Command help message:
+
+```
+Usage: resetprop [options] [args...]
+
+Options:
+   -v      show verbose output
+   -n      only modify property in memory
+
+resetprop  NAME VALUE        set property entry NAME with VALUE
+resetprop  --file FILE       load props from FILE
+resetprop  --delete NAME     remove prop entry NAME
+```
+
+### magiskpolicy
+(This tool is aliased to `supolicy` and `sepolicy-injection` for legacy reasons)
+
+A tool to patch `sepolicy`. **magiskpolicy** also comes with built-in rules to unleash restrictions to make Magisk work properly. `sepolicy` is a compiled binary containing SELinux rules; we directly patch rules in the binary format since we don't have access to the SELinux policy source (`*.te`) files.
+
+The Magisk daemon itself, the root shell, and all processes spawned from the daemon and root shell are all running in the context `u:r:su:s0`. This context is not only patched to be permissive, but also patched to allow any transition from `u:r:su:s0` to any domain. This was done because Samsung devices do not support permissive out of the box.
+
+The built in patches are split to 3 parts: minimal, medium, and large. The full patch will result in a huge policy file, which might cause the `sepolicy` file unable to fit in `boot.img`.
+
+- The minimal patch is just enough to start Magisk daemon and allow the daemon to further patch the policy during boot time (which is called **live patch**). It is done at installation and directly into `boot.img`. 
+- The medium patch covers most common operations, and is live patched as soon as Magisk daemon is started (blocking boot process).
+- The large patch contains the full patch. Due to the concern of greatly increasing the boot time, it is designed to run in the background until it's joined in the non-blocking late_start bootstage.
+
+What this all means is that **only late_start service mode is guaranteed to run in a fully patched environment**. If any script is not time critical, it is **highly recommended to run those scripts in late_start service mode**.
+
+Command help message (very helpful):
+
+```
+Usage: magiskpolicy [--options...] [policystatements...]
+
+Options:
+  --live                directly load patched policy to device
+  --minimal             minimal patches, used for boot image patches
+  --load <infile>       load policies from <infile>
+                        (load from live policies if not specified)
+  --save <outfile>      save policies to <outfile>
+
+magiskpolicy [--options...] [policystatements...]
+
+Options:
+  --live                directly load patched policy to device
+  --minimal             minimal patches, used for boot image patches
+  --load <infile>       load policies from <infile>
+                        (load from live policies if not specified)
+  --save <outfile>      save policies to <outfile>
+
+Policy statements should be enclosed by quotes in command-line;
+the whole statement should be treated as a single parameter.
+
+The statements has a format of "<action> [args...]"
+Use '*' in args to represent every possible match.
+Collections wrapped in curly brackets can also be used as args.
+
+Supported policy statements:
+
+Type 1:
+"<action> source-class target-class permission-class permission"
+Action: allow, deny, auditallow, auditdeny
+
+Type 2:
+"<action> source-class target-class permission-class ioctl range"
+Action: allowxperm, auditallowxperm, dontauditxperm
+
+Type 3:
+"<action> class"
+Action: create, permissive, enforcing
+
+Type 4:
+"attradd class attribute"
+
+Type 5:
+"typetrans source-class target-class permission-class default-class (optional: object-name)"
+
+Notes:
+- typetrans does not support the all match '*' syntax
+- permission-class cannot be collections
+- source-class and target-class can also be attributes
+
+Example: allow { source1 source2 } { target1 target2 } permission-class *
+Will be expanded to:
+
+allow source1 target1 permission-class { all-permissions }
+allow source1 target2 permission-class { all-permissions }
+allow source2 target1 permission-class { all-permissions }
+allow source2 target2 permission-class { all-permissions }
+```
+
+### magiskhide
+This is the command-line tool to control the state of MagiskHide.
+
+Command help message: 
+
+```
+Usage: magiskhide [--options [arguments...] ]
+
+Options:
+  --enable          Start magiskhide
+  --disable         Stop magiskhide
+  --add PROCESS     Add PROCESS to the hide list
+  --rm PROCESS      Remove PROCESS from the hide list
+  --ls              Print out the current hide list
+```