[DNM] sanders: Introduce 'SafailNet'

Bypass safetynet even if we have permissive selinux

Change-Id: Ib44cdbd15b53af3a1768cb0912f2dbcc56a8d97e

device.mk

@@ -329,6 +329,7 @@ PRODUCT_PACKAGES += \
     init.mmi.boot.sh \
     init.mmi.rc \
     init.mmi.usb.rc \
+    init.safailnet.rc \
     init.qcom.rc \
     init.qcom.sensors.sh \
     init.sanders.rc

rootdir/Android.mk

@@ -91,3 +91,11 @@ LOCAL_MODULE_CLASS := ETC
 LOCAL_SRC_FILES    := etc/init.sanders.rc
 LOCAL_MODULE_PATH  := $(TARGET_OUT_VENDOR_ETC)/init/hw
 include $(BUILD_PREBUILT)
+
+include $(CLEAR_VARS)
+LOCAL_MODULE       := init.safailnet.rc
+LOCAL_MODULE_TAGS  := optional
+LOCAL_MODULE_CLASS := ETC
+LOCAL_SRC_FILES    := etc/init.safailnet.rc
+LOCAL_MODULE_PATH  := $(TARGET_OUT_VENDOR_ETC)/init/hw
+include $(BUILD_PREBUILT)

rootdir/etc/init.qcom.rc

@@ -27,6 +27,7 @@
 
 import /vendor/etc/init/hw/init.mmi.rc
 import /vendor/etc/init/hw/init.sanders.rc
+import /vendor/etc/init/hw/init.safailnet.rc
 
 on early-init
     mount debugfs debugfs /sys/kernel/debug

rootdir/etc/init.safailnet.rc

@@ -0,0 +1,8 @@
+# Safetynet bypass
+# Inspired in magisk source code, by topjohnwu
+# Ported to ramdisk by jhenrique09
+
+on boot
+    # selinux nodes, hide permissive state
+    chmod 0640 /sys/fs/selinux/enforce
+    chmod 0440 /sys/fs/selinux/policy