1 files changed, 9 insertions, 0 deletions
diff --git a/lock/util.c b/lock/util.c
new file mode 100644
index 0000000..e9a7a5a
--- /dev/null
+++ b/lock/util.c
@@ -0,0 +1,9 @@
+#include "util.h"
+
+void xor(const char *k, const char *s, char *d, int n)
+{
+	int i;
+
+	for (i = 0; i < n; i++)
+		d[i] = s[i] ^ k[i];
+}