fw/reset.c: oops, forgot to commit the reset protocol handler

fw/reset.c

@@ -0,0 +1,54 @@
+/*
+ * fw/reset.c - Reset protocol
+ *
+ * Written 2012 by Werner Almesberger
+ * Copyright 2012 Werner Almesberger
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+
+#include <stdbool.h>
+#include <stdint.h>
+#include <string.h>
+
+#include <avr/io.h>
+#include <avr/pgmspace.h>
+
+#include "proto.h"
+#include "dispatch.h"
+
+
+/*
+ * For now, we use the unlock secret for reset as well. The reasoning is as
+ * follows:
+ *
+ * - both secrets are transmitted in the clear and can therefore only be
+ *   used in a trusted environment,
+ * - both secrets are used mainly during development and not needed for regular
+ *   operation,
+ * - RESET is normally followed immediately by FIRMWARE, so a listener could
+ *   intercept the secret(s) either way.
+ */
+
+static const uint8_t reset_secret[PAYLOAD] PROGMEM = {
+	#include "unlock-secret.inc"
+};
+
+
+static bool reset_first(uint8_t limit, const uint8_t *payload)
+{
+	if (memcmp_P(payload, reset_secret, PAYLOAD))
+		return 0;
+	WDTCSR = 1 << WDE;
+	return 1;
+}
+
+
+struct handler reset_handler = {
+	.type	= RESET,
+	.first	= reset_first,
+};