1 files changed, 31 insertions, 0 deletions
diff --git a/src/tweakey.h b/src/tweakey.h
new file mode 100644
index 0000000..0642724
--- /dev/null
+++ b/src/tweakey.h
@@ -0,0 +1,31 @@
+#ifndef TWEAKEY_H
+#define TWEAKEY_H
+
+#include <stdint.h>
+
+#include "parameters.h"
+
+
+struct tweakey_state
+{
+    uint8_t TK[TWEAKEY_BYTES];
+};
+
+typedef struct tweakey_state tweakey_state;
+
+
+void tweakey_state_init(
+    tweakey_state *TK,
+    const uint8_t key[KEY_BYTES],
+    const uint8_t tweak[TWEAK_BYTES]
+);
+
+void tweakey_state_extract(
+    const tweakey_state *TK,
+    uint8_t round_tweakey[ROUND_TWEAKEY_BYTES], /* output */
+    uint8_t i                                   /* round constant */
+);
+
+void tweakey_state_update(tweakey_state *TK);
+
+#endif /* TWEAKEY_H */