diff --git a/tests/_test_migration_key b/tests/_test_migration_key
index 3b6db9a..c5b1cc3 100755
--- a/tests/_test_migration_key
+++ b/tests/_test_migration_key
@@ -126,7 +126,7 @@ if [ ! -r $volatilestatefile ]; then
 fi
 
 #ls -l $volatilestatefile
-size=$(stat -c%s $volatilestatefile)
+size=$(get_filesize $volatilestate)
 expsize=1290
 if [ $size -ne $expsize ]; then
 	echo "Error: Unexpected size of volatile state file."
@@ -134,7 +134,7 @@ if [ $size -ne $expsize ]; then
 	exit 1
 fi
 
-hash=$(sha1sum $volatilestatefile | cut -f1 -d" ")
+hash=$(get_sha1_file $volatilestatefile)
 exphash="bafa4b918745dee45537484f1a1089f9967b7df7"
 if [ "$hash" != "$exphash" ]; then
 	echo "Error: The checksum of the volatile state file is wrong."
diff --git a/tests/common b/tests/common
index 6c66c70..733f9ce 100644
--- a/tests/common
+++ b/tests/common
@@ -304,3 +304,29 @@ function run_swtpm_bios()
 		exit 1
 	esac
 }
+
+# Get the size of a file in bytes
+#
+# @1: filename
+function get_filesize()
+{
+	if [[ "$(uname -s)" =~ (Linux|CYGWIN_NT-) ]]; then
+		stat -c%s $1
+	else
+		# OpenBSD
+		stat -f%z $1
+	fi
+}
+
+# Get the SHA1 of a file
+#
+# @1: filename
+function get_sha1_file()
+{
+	if [[ "$(uname -s)" =~ (Linux|CYGWIN_NT-) ]]; then
+		sha1sum $volatilestatefile | cut -f1 -d" "
+	else
+		# OpenBSD
+		sha1 $1 | cut -d "=" -f2 | tr -d " "
+	fi
+}