132 lines
4.1 KiB
C
132 lines
4.1 KiB
C
/**
|
|
* \file gcm.h
|
|
*
|
|
* \brief Galois/Counter mode for AES
|
|
*
|
|
* Copyright (C) 2006-2012, Brainspark B.V.
|
|
*
|
|
* This file is part of PolarSSL (http://www.polarssl.org)
|
|
* Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
|
|
*
|
|
* All rights reserved.
|
|
*
|
|
* 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 2 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, write to the Free Software Foundation, Inc.,
|
|
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
|
|
*/
|
|
#ifndef POLARSSL_GCM_H
|
|
#define POLARSSL_GCM_H
|
|
|
|
#include "aes.h"
|
|
|
|
#include <stdint.h>
|
|
|
|
#define GCM_ENCRYPT 1
|
|
#define GCM_DECRYPT 0
|
|
|
|
#define POLARSSL_ERR_GCM_AUTH_FAILED -0x0012 /**< Authenticated decryption failed. */
|
|
|
|
/**
|
|
* \brief GCM context structure
|
|
*/
|
|
typedef struct {
|
|
aes_context aes_ctx; /*!< AES context used */
|
|
uint64_t HL[16]; /*!< Precalculated HTable */
|
|
uint64_t HH[16]; /*!< Precalculated HTable */
|
|
}
|
|
gcm_context;
|
|
|
|
#ifdef __cplusplus
|
|
extern "C" {
|
|
#endif
|
|
|
|
/**
|
|
* \brief GCM initialization (encryption)
|
|
*
|
|
* \param ctx GCM context to be initialized
|
|
* \param key encryption key
|
|
* \param keysize must be 128, 192 or 256
|
|
*
|
|
* \return 0 if successful, or POLARSSL_ERR_AES_INVALID_KEY_LENGTH
|
|
*/
|
|
int gcm_init( gcm_context *ctx, const unsigned char *key, unsigned int keysize );
|
|
|
|
/**
|
|
* \brief GCM buffer encryption/decryption using AES
|
|
*
|
|
* \param ctx GCM context
|
|
* \param mode GCM_ENCRYPT or GCM_DECRYPT
|
|
* \param length length of the input data
|
|
* \param iv initialization vector
|
|
* \param iv_len length of IV
|
|
* \param add additional data
|
|
* \param add_len length of additional data
|
|
* \param input buffer holding the input data
|
|
* \param output buffer for holding the output data
|
|
* \param tag_len length of the tag to generate
|
|
* \param tag buffer for holding the tag
|
|
*
|
|
* \return 0 if successful
|
|
*/
|
|
int gcm_crypt_and_tag( gcm_context *ctx,
|
|
int mode,
|
|
size_t length,
|
|
const unsigned char *iv,
|
|
size_t iv_len,
|
|
const unsigned char *add,
|
|
size_t add_len,
|
|
const unsigned char *input,
|
|
unsigned char *output,
|
|
size_t tag_len,
|
|
unsigned char *tag );
|
|
|
|
/**
|
|
* \brief GCM buffer authenticated decryption using AES
|
|
*
|
|
* \param ctx GCM context
|
|
* \param length length of the input data
|
|
* \param iv initialization vector
|
|
* \param iv_len length of IV
|
|
* \param add additional data
|
|
* \param add_len length of additional data
|
|
* \param tag buffer holding the tag
|
|
* \param tag_len length of the tag
|
|
* \param input buffer holding the input data
|
|
* \param output buffer for holding the output data
|
|
*
|
|
* \return 0 if successful and authenticated,
|
|
* POLARSSL_ERR_GCM_AUTH_FAILED if tag does not match
|
|
*/
|
|
int gcm_auth_decrypt( gcm_context *ctx,
|
|
size_t length,
|
|
const unsigned char *iv,
|
|
size_t iv_len,
|
|
const unsigned char *add,
|
|
size_t add_len,
|
|
const unsigned char *tag,
|
|
size_t tag_len,
|
|
const unsigned char *input,
|
|
unsigned char *output );
|
|
|
|
/**
|
|
* \brief Checkup routine
|
|
*
|
|
* \return 0 if successful, or 1 if the test failed
|
|
*/
|
|
int gcm_self_test( int verbose );
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
|
|
#endif /* gcm.h */
|