/**************************************************************************/
/*  crypto_core.h                                                         */
/**************************************************************************/
/*                         This file is part of:                          */
/*                             GODOT ENGINE                               */
/*                        https://godotengine.org                         */
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/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur.                  */
/*                                                                        */
/* Permission is hereby granted, free of charge, to any person obtaining  */
/* a copy of this software and associated documentation files (the        */
/* "Software"), to deal in the Software without restriction, including    */
/* without limitation the rights to use, copy, modify, merge, publish,    */
/* distribute, sublicense, and/or sell copies of the Software, and to     */
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#pragma once

#include "core/error/error_list.h"

#include <cstddef>
#include <cstdint>

class String;

class CryptoCore {
private:
	static bool initialized;

public:
	static void initialize();
	static void finalize();

	class MD5Context {
	private:
		void *ctx = nullptr;

	public:
		MD5Context();
		~MD5Context();

		Error start();
		Error update(const uint8_t *p_src, size_t p_len);
		Error finish(unsigned char r_hash[16]);
	};

	class SHA1Context {
	private:
		void *ctx = nullptr;

	public:
		SHA1Context();
		~SHA1Context();

		Error start();
		Error update(const uint8_t *p_src, size_t p_len);
		Error finish(unsigned char r_hash[20]);
	};

	class SHA256Context {
	private:
		void *ctx = nullptr;

	public:
		SHA256Context();
		~SHA256Context();

		Error start();
		Error update(const uint8_t *p_src, size_t p_len);
		Error finish(unsigned char r_hash[32]);
	};

	class AESContext {
	public:
		enum class Mode {
			NONE,
			ENCRYPT,
			DECRYPT,
		};
		enum class Cipher {
			NONE,
			CBC,
			CFB,
			ECB,
		};

	private:
		uint32_t key_id = 0;
		uint32_t alg = 0;
		void *ctx = nullptr;

		void reset();

	public:
		AESContext();
		~AESContext();

		Error setup(Mode p_mode, Cipher p_cipher, const uint8_t *p_key, size_t p_key_length, const uint8_t *p_iv, size_t p_iv_size);
		Error update(const uint8_t *p_src, size_t p_src_size, uint8_t *r_dst, size_t p_dst_size);
		Error finish(uint8_t *r_dst, size_t p_dst_size);
	};

	static Error generate_random(uint8_t *r_buffer, size_t p_buffer_len);

	static String b64_encode_str(const uint8_t *p_src, size_t p_src_len);
	static Error b64_encode(uint8_t *r_dst, size_t p_dst_len, size_t *r_len, const uint8_t *p_src, size_t p_src_len);
	static Error b64_decode(uint8_t *r_dst, size_t p_dst_len, size_t *r_len, const uint8_t *p_src, size_t p_src_len);

	static Error md5(const uint8_t *p_src, size_t p_src_len, unsigned char r_hash[16]);
	static Error sha1(const uint8_t *p_src, size_t p_src_len, unsigned char r_hash[20]);
	static Error sha256(const uint8_t *p_src, size_t p_src_len, unsigned char r_hash[32]);

	static Error encrypt_cfb(const uint8_t *p_src, uint8_t *r_dst, size_t p_length, const uint8_t *p_key, size_t p_key_length, const uint8_t p_iv[16]);
	static Error decrypt_cfb(const uint8_t *p_src, uint8_t *r_dst, size_t p_length, const uint8_t *p_key, size_t p_key_length, const uint8_t p_iv[16]);
};