lib/enable: validate params->version

Make libfsverity_enable() validate that
libfsverity_merkle_tree_params::version is set to 1.

This allows for future extensibility, and it matches what
libfsverity_compute_digest() does.

Signed-off-by: Eric Biggers <ebiggers@google.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/lib/enable.c b/lib/enable.c
index c27ec89..2478077 100644
--- a/lib/enable.c
+++ b/lib/enable.c
@@ -31,6 +31,12 @@ libfsverity_enable_with_sig(int fd,
 		return -EINVAL;
 	}
 
+	if (params->version != 1) {
+		libfsverity_error_msg("unsupported version (%u)",
+				      params->version);
+		return -EINVAL;
+	}
+
 	arg.version = 1;
 	arg.hash_algorithm =
 		params->hash_algorithm ?: FS_VERITY_HASH_ALG_DEFAULT;