Created libattestation

Move attestation logic from input into separate library. This way Input
and SurfaceFlinger can leverage the same logic

Test: inputflinger_test
Test: attestation_tests
Bug: 155825630
Change-Id: Ia4f65166da8a1c53a9570db59eab602190438696
diff --git a/services/inputflinger/dispatcher/InputDispatcher.h b/services/inputflinger/dispatcher/InputDispatcher.h
index 8988714..e452ca2 100644
--- a/services/inputflinger/dispatcher/InputDispatcher.h
+++ b/services/inputflinger/dispatcher/InputDispatcher.h
@@ -31,6 +31,7 @@
 #include "TouchState.h"
 #include "TouchedWindow.h"
 
+#include <attestation/HmacKeyManager.h>
 #include <input/Input.h>
 #include <input/InputApplication.h>
 #include <input/InputTransport.h>
@@ -58,16 +59,6 @@
 
 class Connection;
 
-class HmacKeyManager {
-public:
-    HmacKeyManager();
-    std::array<uint8_t, 32> sign(const VerifiedInputEvent& event) const;
-
-private:
-    std::array<uint8_t, 32> sign(const uint8_t* data, size_t size) const;
-    const std::array<uint8_t, 128> mHmacKey;
-};
-
 /* Dispatches events to input targets.  Some functions of the input dispatcher, such as
  * identifying input targets, are controlled by a separate policy object.
  *
@@ -133,6 +124,8 @@
     virtual status_t unregisterInputChannel(const InputChannel& inputChannel) override;
     virtual status_t pilferPointers(const sp<IBinder>& token) override;
 
+    std::array<uint8_t, 32> sign(const VerifiedInputEvent& event) const;
+
 private:
     enum class DropReason {
         NOT_DROPPED,