Refactor "ext4 encryption" code into libfscrypt

File-based encryption related code no longer belongs in ext4_utils, as
it is now used on both ext4 and f2fs, since both filesystems share the
same kernel API for encryption.  Refactor it into its own library,
libfscrypt.

Note that the keyring is renamed from "e4crypt" to "fscrypt", which is
technically a user-visible change, but as far as I know nothing depends
on it other than vold which is being updated too.

Test: built, booted device with f2fs encryption
Change-Id: I3c302564262412a5d5e672bd213e7cfada5f49cc

1 files changed, 17 insertions, 0 deletions

diff --git a/libfscrypt/Android.bp b/libfscrypt/Android.bp
new file mode 100644
index 00000000..cca38235
--- /dev/null
+++ b/libfscrypt/Android.bp
@@ -0,0 +1,17 @@
+// Copyright 2018 The Android Open Source Project
+
+cc_library {
+    name: "libfscrypt",
+    recovery_available: true,
+    srcs: [
+        "fscrypt.cpp",
+        "fscrypt_init_extensions.cpp",
+    ],
+    export_include_dirs: ["include"],
+    shared_libs: [
+        "libbase",
+        "libcutils",
+        "libkeyutils",
+        "liblogwrap",
+    ],
+}