From 0e2d72ecc70eb00a6f5df69efd915c207cf6b89e Mon Sep 17 00:00:00 2001
From: Gabriele M <moto.falcon.git@gmail.com>
Date: Mon, 27 Feb 2017 15:44:17 +0100
Subject: [PATCH] backuptool: Preserve the SELinux context of the files

Add a function that allows to copy files preserving their SELinux
context that is generic enough to work with both busybox and toybox.

Change-Id: If2c245863df5675c18dbf43b6bcedeb33383fc38
---
 prebuilt/common/bin/backuptool.functions | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/prebuilt/common/bin/backuptool.functions b/prebuilt/common/bin/backuptool.functions
index c7e47b9c..4528a337 100644
--- a/prebuilt/common/bin/backuptool.functions
+++ b/prebuilt/common/bin/backuptool.functions
@@ -7,6 +7,16 @@ export C=/tmp/backupdir
 export S=/system
 export V=14.1
 
+copy_file() {
+  cp -dp "$1" "$2"
+  # symlinks don't have a context
+  if [ ! -L "$1" ]; then
+    # it is assumed that every label starts with 'u:object_r' and has no white-spaces
+    local context=`ls -Z "$1" | grep -o 'u:object_r:[^ ]*' | head -1`
+    chcon "$context" "$2"
+  fi
+}
+
 backup_file() {
   if [ -e "$1" -o -L "$1" ]; then
     local F=`basename "$1"`
@@ -16,7 +26,7 @@ backup_file() {
       echo "Skipping odexed apk $1";
     else
       mkdir -p "$C/$D"
-      cp -dp $1 "$C/$D/$F"
+      copy_file "$1" "$C/$D/$F"
     fi
   fi
 }
@@ -28,7 +38,7 @@ restore_file() {
     if [ ! -d "$DIR" ]; then
       mkdir -p "$DIR";
     fi
-    cp -dp "$C/$DIR/$FILE" "$1";
+    copy_file "$C/$DIR/$FILE" "$1";
     if [ -n "$2" ]; then
       echo "Deleting obsolete file $2"
       rm "$2";