ubifs: Implement UBIFS_FLG_ENCRYPTION
This feature flag indicates that the filesystem contains encrypted
files.
Signed-off-by: Richard Weinberger <richard@nod.at>
diff --git a/fs/ubifs/sb.c b/fs/ubifs/sb.c
index 4a2b4c3..54cef70 100644
--- a/fs/ubifs/sb.c
+++ b/fs/ubifs/sb.c
@@ -622,6 +622,16 @@
c->big_lpt = !!(sup_flags & UBIFS_FLG_BIGLPT);
c->space_fixup = !!(sup_flags & UBIFS_FLG_SPACE_FIXUP);
c->double_hash = !!(sup_flags & UBIFS_FLG_DOUBLE_HASH);
+ c->encrypted = !!(sup_flags & UBIFS_FLG_ENCRYPTION);
+
+#ifndef CONFIG_UBIFS_FS_ENCRYPTION
+ if (c->encrypted) {
+ ubifs_err(c, "file system contains encrypted files but UBIFS"
+ " was built without crypto support.");
+ err = -EINVAL;
+ goto out;
+ }
+#endif
/* Automatically increase file system size to the maximum size */
c->old_leb_cnt = c->leb_cnt;
@@ -809,3 +819,33 @@
ubifs_msg(c, "free space fixup complete");
return err;
}
+
+int ubifs_enable_encryption(struct ubifs_info *c)
+{
+ int err;
+ struct ubifs_sb_node *sup;
+
+ if (c->encrypted)
+ return 0;
+
+ if (c->ro_mount || c->ro_media)
+ return -EROFS;
+
+ if (c->fmt_version < 5) {
+ ubifs_err(c, "on-flash format version 5 is needed for encryption");
+ return -EINVAL;
+ }
+
+ sup = ubifs_read_sb_node(c);
+ if (IS_ERR(sup))
+ return PTR_ERR(sup);
+
+ sup->flags |= cpu_to_le32(UBIFS_FLG_ENCRYPTION);
+
+ err = ubifs_write_sb_node(c, sup);
+ if (!err)
+ c->encrypted = 1;
+ kfree(sup);
+
+ return err;
+}