Implement masterkey logic, KEYSLOT defines.

exosphere/masterkey.h

@@ -0,0 +1,16 @@
+#ifndef EXOSPHERE_MASTERKEY_H
+#define EXOSPHERE_MASTERKEY_H
+
+/* This is glue code to enable master key support across versions. */
+
+/* TODO: Update to 0x5 on release of new master key. */
+#define MASTERKEY_REVISION_MAX 0x4
+
+/* This should be called early on in initialization. */
+void mkey_detect_revision(void);
+
+unsigned int mkey_get_revision(void);
+
+unsigned int mkey_get_keyslot(unsigned int revision);
+
+#endif