/*  Copyright (C) 2020 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz>

    This program 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.

    This program 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 this program.  If not, see <https://www.gnu.org/licenses/>.
 */

/*!
 * \brief Base64url implementation (RFC 4648).
 */

#pragma once

#include <stdint.h>

/*!
 * \brief Encodes binary data using Base64.
 *
 * \note Output data buffer contains Base64 text string which isn't
 *       terminated with '\0'!
 *
 * \param in		Input binary data.
 * \param in_len	Length of input data.
 * \param out		Output data buffer.
 * \param out_len	Size of output buffer.
 *
 * \retval >=0		length of output string.
 * \retval KNOT_E*	if error.
 */
int32_t kr_base64url_encode(const uint8_t  *in,
                      const uint32_t in_len,
                      uint8_t        *out,
                      const uint32_t out_len);

/*!
 * \brief Encodes binary data using Base64 and output stores to own buffer.
 *
 * \note Output data buffer contains Base64 text string which isn't
 *       terminated with '\0'!
 *
 * \note Output buffer should be deallocated after use.
 *
 * \param in		Input binary data.
 * \param in_len	Length of input data.
 * \param out		Output data buffer.
 *
 * \retval >=0		length of output string.
 * \retval KNOT_E*	if error.
 */
int32_t kr_base64url_encode_alloc(const uint8_t  *in,
                            const uint32_t in_len,
                            uint8_t        **out);

/*!
 * \brief Decodes text data using Base64.
 *
 * \note Input data needn't be terminated with '\0'.
 *
 * \note Input data must be continuous Base64 string!
 *
 * \param in		Input text data.
 * \param in_len	Length of input string.
 * \param out		Output data buffer.
 * \param out_len	Size of output buffer.
 *
 * \retval >=0		length of output data.
 * \retval KNOT_E*	if error.
 */
int32_t kr_base64url_decode(const uint8_t  *in,
                      uint32_t       in_len,
                      uint8_t        *out,
                      const uint32_t out_len);

/*!
 * \brief Decodes text data using Base64 and output stores to own buffer.
 *
 * \note Input data needn't be terminated with '\0'.
 *
 * \note Input data must be continuous Base64 string!
 *
 * \note Output buffer should be deallocated after use.
 *
 * \param in		Input text data.
 * \param in_len	Length of input string.
 * \param out		Output data buffer.
 *
 * \retval >=0		length of output data.
 * \retval KNOT_E*	if error.
 */
int32_t kr_base64url_decode_alloc(const uint8_t  *in,
                            const uint32_t in_len,
                            uint8_t        **out);

/*! @} */
