commit 6ef1df0412a484d04749ed55d7d366d2cdaf767a
author George G <kreach3r@users.noreply.github.com> Sat Feb 25 17:20:33 2017 +0200
committer Nathan Chancellor <natechancellor@gmail.com> Sun Mar 05 02:33:21 2017 +0100
tree ea6fffdea0accc639e14b5a6d55a208686ddba62
parent 88088a462f084679dcdf27d78c9530e1d1d01dbd

Introducing Signature check in Masquerade (1/3)

This commit introduces a signing Signature check against all AUTHORIZED_CALLERS.
It can be bypassed automatically if the ROM is a userdebug or eng build, or if
the user has explicitly toggled "Developer options" secure setting.

The Signature String was produced with the following call:
log(pi.signatures[0].toCharsString());

and it was deliberately added into Java and not a Resources string so it will
be impossible to overlay.

The build type check was made configurable for OEMs using a prop value:
ro.masquerade.buildtype.check

the ro.* namespace was chosen for better user security (it shouldn't be writable)

It borrows some of the signature check code from the DashClock app:
https://github.com/romannurik/dashclock/commit/a9bf6636f764b150d489d0817ee7f7796af1a155

Change-Id: I6e9bb97de02a9cc89e57fd4099230cd86e820aa9