1 files changed, 24 insertions, 0 deletions
diff --git a/hmac/libkeccak_hmac_wipe.c b/hmac/libkeccak_hmac_wipe.c
new file mode 100644
index 0000000..ec0be2d
--- /dev/null
+++ b/hmac/libkeccak_hmac_wipe.c
@@ -0,0 +1,24 @@
+/* See LICENSE file for copyright and license details. */
+#include "../common.h"
+
+
+/**
+ * Wipe sensitive data wihout freeing any data
+ * 
+ * @param  state  The state that should be wipe
+ */
+void
+libkeccak_hmac_wipe(volatile struct libkeccak_hmac_state *state)
+{
+	volatile unsigned char *restrict key_pads;
+	size_t i, size;
+
+	key_pads = state->key_opad;
+	size = 2 * ((state->key_length + 7) >> 3);
+
+	libkeccak_state_wipe(&state->sponge);
+	for (i = 0; i < size; i++)
+		key_pads[i] = 0;
+	state->leftover = 0;
+	__builtin_memset(state->buffer, 0, state->buffer_size);
+}