eCryptfs: allow userspace messaging to be disabled
When the userspace messaging (for the less common case of userspace key
wrap/unwrap via ecryptfsd) is not needed, allow eCryptfs to build with
it removed. This saves on kernel code size and reduces potential attack
surface by removing the /dev/ecryptfs node.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
diff --git a/fs/ecryptfs/Kconfig b/fs/ecryptfs/Kconfig
index cc16562..1f63120 100644
--- a/fs/ecryptfs/Kconfig
+++ b/fs/ecryptfs/Kconfig
@@ -12,3 +12,11 @@
To compile this file system support as a module, choose M here: the
module will be called ecryptfs.
+
+config ECRYPT_FS_MESSAGING
+ bool "Enable notifications for userspace key wrap/unwrap"
+ depends on ECRYPT_FS
+ help
+ Enables the /dev/ecryptfs entry for use by ecryptfsd. This allows
+ for userspace to wrap/unwrap file encryption keys by other
+ backends, like OpenSSL.