ZeroTierOne/core/Poly1305.hpp

/*
 * Copyright (c)2013-2020 ZeroTier, Inc.
 *
 * Use of this software is governed by the Business Source License included
 * in the LICENSE.TXT file in the project's root directory.
 *
 * Change Date: 2025-01-01
 *
 * On the date above, in accordance with the Business Source License, use
 * of this software will be governed by version 2.0 of the Apache License.
 */
/****/

#ifndef ZT_POLY1305_HPP
#define ZT_POLY1305_HPP

namespace ZeroTier {

#define ZT_POLY1305_KEY_SIZE 32
#define ZT_POLY1305_MAC_SIZE 16

/**
 * Poly1305 one-time MAC calculator
 */
class Poly1305
{
public:
	ZT_INLINE Poly1305()
	{}

	ZT_INLINE Poly1305(const void *key)
	{ this->init(key); }

	void init(const void *key) noexcept;

	void update(const void *data, unsigned int len) noexcept;

	void finish(void *auth) noexcept;

	static ZT_INLINE void compute(void *const auth, const void *const data, const unsigned int len, const void *const key) noexcept
	{
		Poly1305 p(key);
		p.update(data, len);
		p.finish(auth);
	}

private:
	struct
	{
		size_t aligner;
		unsigned char opaque[136];
	} ctx;
};

} // namespace ZeroTier

#endif