1 files changed, 40 insertions, 0 deletions
diff --git a/src/crypto/hash.h b/src/crypto/hash.h
new file mode 100644
index 000000000..32e8f4701
--- /dev/null
+++ b/src/crypto/hash.h
@@ -0,0 +1,40 @@
+#pragma once
+
+#include <assert.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+
+#include "int-util.h"
+
+static inline void *padd(void *p, size_t i) {
+  return (char *) p + i;
+}
+
+static inline const void *cpadd(const void *p, size_t i) {
+  return (const char *) p + i;
+}
+
+static_assert(sizeof(size_t) == 4 || sizeof(size_t) == 8, "size_t must be 4 or 8 bytes long");
+static inline void place_length(uint8_t *buffer, size_t bufsize, size_t length) {
+  if (sizeof(size_t) == 4) {
+    *(uint32_t *) padd(buffer, bufsize - 4) = swap32be(length);
+  } else {
+    *(uint64_t *) padd(buffer, bufsize - 8) = swap64be(length);
+  }
+}
+
+struct keccak_state {
+  union {
+    uint8_t b[200];
+    uint64_t w[25];
+  };
+};
+
+enum {
+  HASH_SIZE = 32,
+  HASH_DATA_AREA = 136
+};
+
+void keccak(const void *data, size_t length, char *hash);
+void keccak_permutation(struct keccak_state *state);
+\ No newline at end of file