diff --git a/lsflib/src/xor.c b/lsflib/src/xor.c
new file mode 100644
--- /dev/null
+++ b/lsflib/src/xor.c
@@ -0,0 +1,17 @@
+/*
+ *  $Id: xor.c 94 2008-04-05 01:27:30Z mbroeker $
+ * $URL: http://localhost/svn/c/lsflib/trunk/src/xor.c $
+ *
+ */
+
+#include <string.h>
+
+char *xor (char *s, char key)
+{
+    int i;
+
+    for (i = 0; i < strlen (s); i++)
+        s[i] ^= key;
+
+    return s;
+}