diff --git a/lib/asn1/code.c b/lib/asn1/code.c
new file mode 100644
index 000000000..44e24abc6
--- /dev/null
+++ b/lib/asn1/code.c
@@ -0,0 +1,67 @@
+
+#include "der_locl.h"
+
+enum prim_opcode {
+    HAP_BOOLEAN = 0
+};
+
+typedef size_t (*op_length)(const void *);
+typedef int    (*op_get)(const unsigned char *, size_t, void *, size_t *);
+typedef int    (*op_put)(unsigned char *, size_t, const void *, size_t *);
+typedef int    (*op_release)(void *);
+typedef int    (*op_parse)(const char *, void *);
+typedef size_t (*op_print)(const void *, char *, size_t);
+
+/* flags */
+#define OPTIONAL 1
+
+struct op {
+    /* must implement */
+    int         dertype;
+    const char *name;
+    size_t	datasize;
+    op_length   length;
+    op_get      get;
+    op_put      put;
+    op_release  release;
+    /* may implement */
+    op_parse    parse;
+    op_print    print;
+};
+
+/* primitive operatators */
+
+struct op pops[] = {
+    {
+	UT_EndOfContent,
+	"EndOfContent"
+    },
+    {
+	UT_Boolean,
+	"boolean",
+	sizeof(int),
+	(op_length)der_length_boolean,
+	(op_get)der_get_boolean,
+	(op_put)der_put_boolean,
+	(op_release)der_free_generic,
+	NULL,
+	NULL
+    }
+};
+
+int
+asn1code_decode_type(unsigned int op,
+		     const unsigned char *in, size_t len,
+		     void *data, size_t *size);
+
+
+
+int
+asn1code_decode_type(unsigned int op,
+		     const unsigned char *in, size_t len,
+		     void *data, size_t *size)
+{
+    if (op > sizeof(pops)/sizeof(pops[0]))
+	return -1;
+    return (pops[op].get)(in, len, data, size);
+}