1 files changed, 56 insertions, 0 deletions
diff --git a/src/crypto/chacha8.h b/src/crypto/chacha8.h
new file mode 100644
index 000000000..e4fe46799
--- /dev/null
+++ b/src/crypto/chacha8.h
@@ -0,0 +1,56 @@
+// Copyright (c) 2012-2013 The Cryptonote developers
+// Distributed under the MIT/X11 software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#pragma once
+
+#include <stdint.h>
+#include <stddef.h>
+
+#define CHACHA8_KEY_SIZE 32
+#define CHACHA8_IV_SIZE 8
+
+#if defined(__cplusplus)
+#include <memory.h>
+
+#include "hash.h"
+
+namespace crypto {
+  extern "C" {
+#endif
+    void chacha8(const void* data, size_t length, const uint8_t* key, const uint8_t* iv, char* cipher);
+#if defined(__cplusplus)
+  }
+
+#pragma pack(push, 1)
+  struct chacha8_key {
+    uint8_t data[CHACHA8_KEY_SIZE];
+
+    ~chacha8_key()
+    {
+      memset(data, 0, sizeof(data));
+    }
+  };
+
+  // MS VC 2012 doesn't interpret `class chacha8_iv` as POD in spite of [9.0.10], so it is a struct
+  struct chacha8_iv {
+    uint8_t data[CHACHA8_IV_SIZE];
+  };
+#pragma pack(pop)
+
+  static_assert(sizeof(chacha8_key) == CHACHA8_KEY_SIZE && sizeof(chacha8_iv) == CHACHA8_IV_SIZE, "Invalid structure size");
+
+  inline void chacha8(const void* data, std::size_t length, const chacha8_key& key, const chacha8_iv& iv, char* cipher) {
+    chacha8(data, length, reinterpret_cast<const uint8_t*>(&key), reinterpret_cast<const uint8_t*>(&iv), cipher);
+  }
+
+  inline void generate_chacha8_key(std::string password, chacha8_key& key) {
+    static_assert(sizeof(chacha8_key) <= sizeof(hash), "Size of hash must be at least that of chacha8_key");
+    char pwd_hash[HASH_SIZE];
+    crypto::cn_slow_hash(password.data(), password.size(), pwd_hash);
+    memcpy(&key, pwd_hash, sizeof(key));
+    memset(pwd_hash, 0, sizeof(pwd_hash));
+  }
+}
+
+#endif