mbedtls/include/mbedtls/poly1305.h
Daniel King a310c5e42b Allow some parameters to be NULL if the length is 0.
This change permits users of the ChaCha20/Poly1305 algorithms
(and the AEAD construction thereof) to pass NULL pointers for
data that they do not need, and avoids the need to provide a valid
buffer for data that is not used.
2018-05-24 13:37:31 +02:00

144 lines
5 KiB
C

/**
* \file poly1305.h
*
* \brief Poly1305 authenticator algorithm.
*
* Copyright (C) 2006-2016, ARM Limited, All Rights Reserved
* SPDX-License-Identifier: Apache-2.0
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may
* not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* This file is part of mbed TLS (https://tls.mbed.org)
*/
#ifndef MBEDTLS_POLY1305_H
#define MBEDTLS_POLY1305_H
#if !defined(MBEDTLS_CONFIG_FILE)
#include "mbedtls/config.h"
#else
#include MBEDTLS_CONFIG_FILE
#endif
#include <stdint.h>
#include <stddef.h>
#if !defined(MBEDTLS_POLY1305_ALT)
#define MBEDTLS_ERR_POLY1305_BAD_INPUT_DATA -0x0041 /**< Invalid input parameter(s). */
typedef struct
{
uint32_t r[4]; /** Stores the value for 'r' (low 128 bits of the key) */
uint32_t s[4]; /** Stores the value for 's' (high 128 bits of the key) */
uint32_t acc[5]; /** Accumulator number */
uint8_t queue[16]; /** Stores partial block data */
size_t queue_len; /** Number of bytes stored in 'queue'. Always less than 16 */
}
mbedtls_poly1305_context;
/**
* \brief Initialize a Poly1305 context
*
* \param ctx The Poly1305 context to be initialized
*/
void mbedtls_poly1305_init( mbedtls_poly1305_context *ctx );
/**
* \brief Clear a Poly1305 context
*
* \param ctx The Poly1305 context to be cleared
*/
void mbedtls_poly1305_free( mbedtls_poly1305_context *ctx );
/**
* \brief Set the Poly1305 authentication key.
*
* \warning The key should be unique, and \b MUST be
* unpredictable for each invocation of Poly1305.
*
* \param ctx The Poly1305 context.
* \param key Buffer containing the 256-bit key.
*
* \return MBEDTLS_ERR_POLY1305_BAD_INPUT_DATA is returned if ctx
* or key are NULL.
* Otherwise, 0 is returned to indicate success.
*/
int mbedtls_poly1305_setkey( mbedtls_poly1305_context *ctx,
const unsigned char key[32] );
/**
* \brief Process data with Poly1305.
*
* This function can be called multiple times to process
* a stream of data.
*
* \param ctx The Poly1305 context.
* \param ilen The input length (in bytes). Any value is accepted.
* \param input Buffer containing the input data to Process.
* This pointer can be NULL if ilen == 0.
*
* \return MBEDTLS_ERR_POLY1305_BAD_INPUT_DATA is returned if ctx
* or input are NULL.
* Otherwise, 0 is returned to indicate success.
*/
int mbedtls_poly1305_update( mbedtls_poly1305_context *ctx,
size_t ilen,
const unsigned char *input );
/**
* \brief Generate the Poly1305 MAC.
*
* \param ctx The Poly1305 context.
* \param mac Buffer to where the MAC is written. Must be big enough
* to hold the 16-byte MAC.
*
* \return MBEDTLS_ERR_POLY1305_BAD_INPUT_DATA is returned if ctx
* or mac are NULL.
* Otherwise, 0 is returned to indicate success.
*/
int mbedtls_poly1305_finish( mbedtls_poly1305_context *ctx,
unsigned char mac[16] );
#else /* MBEDTLS_POLY1305_ALT */
#include "poly1305_alt.h"
#endif /* MBEDTLS_POLY1305_ALT */
/**
* \brief Generate the Poly1305 MAC of some data with the given key.
*
* \warning The key should be unique, and \b MUST be
* unpredictable for each invocation of Poly1305.
*
* \param key Buffer containing the 256-bit (32 bytes) key.
* \param ilen The length of the input data (in bytes).
* \param input Buffer containing the input data to process.
* \param mac Buffer to where the 128-bit (16 bytes) MAC is written.
*
* \return MBEDTLS_ERR_POLY1305_BAD_INPUT_DATA is returned if key,
* input, or mac are NULL.
* Otherwise, 0 is returned to indicate success.
*/
int mbedtls_poly1305_mac( const unsigned char key[32],
size_t ilen,
const unsigned char *input,
unsigned char mac[16] );
/**
* \brief Checkup routine
*
* \return 0 if successful, or 1 if the test failed
*/
int mbedtls_poly1305_self_test( int verbose );
#endif /* MBEDTLS_POLY1305_H */