Support backup/restore of FBE policies

Change-Id: Iba8ef20f57b0fb57bb9406c53148a806441d0b59
diff --git a/crypto/ext4crypt/Android.mk b/crypto/ext4crypt/Android.mk
index 531aca1..bcbcccf 100644
--- a/crypto/ext4crypt/Android.mk
+++ b/crypto/ext4crypt/Android.mk
@@ -5,7 +5,7 @@
 LOCAL_MODULE := libe4crypt
 LOCAL_MODULE_TAGS := eng optional
 LOCAL_CFLAGS :=
-LOCAL_SRC_FILES := Decrypt.cpp Ext4Crypt.cpp Keymaster.cpp KeyStorage.cpp ScryptParameters.cpp Utils.cpp HashPassword.cpp
+LOCAL_SRC_FILES := Decrypt.cpp Ext4Crypt.cpp Keymaster.cpp KeyStorage.cpp ScryptParameters.cpp Utils.cpp HashPassword.cpp ext4_crypt.cpp
 LOCAL_SHARED_LIBRARIES := libselinux libc libc++ libext4_utils libsoftkeymaster libbase libcrypto libcutils libkeymaster_messages libhardware libprotobuf-cpp-lite
 LOCAL_STATIC_LIBRARIES := libscrypt_static
 LOCAL_C_INCLUDES := system/extras/ext4_utils external/scrypt/lib/crypto system/security/keystore hardware/libhardware/include/hardware system/security/softkeymaster/include/keymaster system/keymaster/include
@@ -30,4 +30,15 @@
 
 include $(BUILD_EXECUTABLE)
 
+include $(CLEAR_VARS)
+LOCAL_MODULE := e4policyget
+LOCAL_MODULE_TAGS := optional
+LOCAL_MODULE_CLASS := RECOVERY_EXECUTABLES
+LOCAL_MODULE_PATH := $(TARGET_RECOVERY_ROOT_OUT)/sbin
+LOCAL_SRC_FILES := e4policyget.cpp
+LOCAL_SHARED_LIBRARIES := libe4crypt
+LOCAL_LDFLAGS += -Wl,-dynamic-linker,/sbin/linker64
+
+include $(BUILD_EXECUTABLE)
+
 endif