[PATCH 03/10] common/verity: use FSV_BLOCK_SIZE by default

[Eric Biggers <ebiggers@kernel.org>]

From: Eric Biggers <ebiggers@google.com>

Make _fsv_enable() and _fsv_sign() default to FSV_BLOCK_SIZE if no block
size is explicitly specified, so that the individual tests don't have to
do this themselves.  This overrides the fsverity-utils default of 4096
bytes, or the page size in older versions of fsverity-utils, both of
which may differ from FSV_BLOCK_SIZE.

Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 common/verity | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/common/verity b/common/verity
index a94ebf8e..1c706b80 100644
--- a/common/verity
+++ b/common/verity
@@ -249,7 +249,13 @@ _fsv_dump_signature()
 
 _fsv_enable()
 {
-	$FSVERITY_PROG enable "$@"
+	local args=("$@")
+	# If the caller didn't explicitly specify a Merkle tree block size, then
+	# use FSV_BLOCK_SIZE.
+	if ! [[ " $*" =~ " --block-size" ]]; then
+		args+=("--block-size=$FSV_BLOCK_SIZE")
+	fi
+	$FSVERITY_PROG enable "${args[@]}"
 }
 
 _fsv_measure()
@@ -259,7 +265,13 @@ _fsv_measure()
 
 _fsv_sign()
 {
-	$FSVERITY_PROG sign "$@"
+	local args=("$@")
+	# If the caller didn't explicitly specify a Merkle tree block size, then
+	# use FSV_BLOCK_SIZE.
+	if ! [[ " $*" =~ " --block-size" ]]; then
+		args+=("--block-size=$FSV_BLOCK_SIZE")
+	fi
+	$FSVERITY_PROG sign "${args[@]}"
 }
 
 # Generate a file, then enable verity on it.
-- 
2.38.1