ubifs: Add skeleton for fscrypto
This is the first building block to provide file level
encryption on UBIFS.
Signed-off-by: Richard Weinberger <richard@nod.at>
diff --git a/fs/ubifs/crypto.c b/fs/ubifs/crypto.c
new file mode 100644
index 0000000..12a0072
--- /dev/null
+++ b/fs/ubifs/crypto.c
@@ -0,0 +1,46 @@
+#include "ubifs.h"
+
+static int ubifs_crypt_get_context(struct inode *inode, void *ctx, size_t len)
+{
+ return ubifs_xattr_get(inode, UBIFS_XATTR_NAME_ENCRYPTION_CONTEXT,
+ ctx, len);
+}
+
+static int ubifs_crypt_set_context(struct inode *inode, const void *ctx,
+ size_t len, void *fs_data)
+{
+ return ubifs_xattr_set(inode, UBIFS_XATTR_NAME_ENCRYPTION_CONTEXT,
+ ctx, len, 0);
+}
+
+static bool ubifs_crypt_empty_dir(struct inode *inode)
+{
+ return ubifs_check_dir_empty(inode) == 0;
+}
+
+static unsigned int ubifs_crypt_max_namelen(struct inode *inode)
+{
+ if (S_ISLNK(inode->i_mode))
+ return UBIFS_MAX_INO_DATA;
+ else
+ return UBIFS_MAX_NLEN;
+}
+
+static int ubifs_key_prefix(struct inode *inode, u8 **key)
+{
+ static char prefix[] = "ubifs:";
+
+ *key = prefix;
+
+ return sizeof(prefix) - 1;
+}
+
+struct fscrypt_operations ubifs_crypt_operations = {
+ .flags = FS_CFLG_INPLACE_ENCRYPTION,
+ .get_context = ubifs_crypt_get_context,
+ .set_context = ubifs_crypt_set_context,
+ .is_encrypted = ubifs_crypt_is_encrypted,
+ .empty_dir = ubifs_crypt_empty_dir,
+ .max_namelen = ubifs_crypt_max_namelen,
+ .key_prefix = ubifs_key_prefix,
+};