1 files changed, 50 insertions, 0 deletions
diff --git a/src/crypto.h b/src/crypto.h
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+/* crypto.h -- Code for deriving encryption keys.
+
+   Copyright (C) 2017 Jakob Tsar-Fox, All Rights Reserved.
+
+   This file is part of Nekopack.
+
+   Nekopack is free software: you can redistribute it and/or modify it
+   under the terms of the GNU General Public License as published by the
+   Free Software Foundation, either version 3 of the License, or (at
+   your option) any later version.
+
+   Nekopack is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+   General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with Nekopack. If not, see <http://www.gnu.org/licenses/>. */
+
+#pragma once
+
+#include <stdbool.h>
+#include <stdint.h>
+
+/* Game identifiers for use with get_key. */
+enum {
+    NONE,
+    NEKOPARA_VOLUME_0,
+    NEKOPARA_VOLUME_0_STEAM,
+    NEKOPARA_VOLUME_1,
+    NEKOPARA_VOLUME_1_STEAM,
+};
+
+/* Structure containing game-specific encryption information. */
+struct game_key {
+    bool     uses_initial; /* Whether or not to use an initial key. */
+    uint32_t master; /* Master key specific to the game. */
+    uint8_t  fallback_initial; /* Fallback if initial key is 0. */
+    uint8_t  fallback_primary; /* Fallback if primary key is 0. */
+};
+
+/* Returns the game_key structure for a given game identifier, as
+   defined in crypto.h */
+struct game_key get_key(int game);
+
+/* Generates an initial key for the given key structure and file key. */
+uint8_t derive_initial(struct game_key k, uint64_t file_key);
+
+/* Generates a primary key for the given key structure and file key. */
+uint8_t derive_primary(struct game_key k, uint64_t file_key);