/** @file

 * Encryption and decryption routines implementing the EAX' encryption mode

 * Copyright 2010, Edward J. Beroset, edward.j.beroset@us.elster.com

 *

 * Wireshark - Network traffic analyzer

 * By Gerald Combs <gerald@wireshark.org>

 * Copyright 1998 Gerald Combs

 *

 * SPDX-License-Identifier: GPL-2.0-or-later

 */

#ifndef _EAX_H

#define _EAX_H

#include <wireshark.h>

typedef struct tagMAC_T

{

    uint8_t Mac[4];

} MAC_T;

#define EAX_MODE_CLEARTEXT_AUTH     1

#define EAX_MODE_CIPHERTEXT_AUTH    2

#define EAX_SIZEOF_KEY              16

/*!

 Decrypts cleartext data using EAX' mode (see ANSI Standard C12.22-2008).

 @param[in] pN  pointer to cleartext (canonified form)

 @param[in] pK  pointer to secret key

 @param[in,out] pC  pointer to ciphertext

 @param[in] SizeN byte length of cleartext (pN) buffer

 @param[in] SizeK byte length of secret key (pK)

 @param[in] SizeC byte length of ciphertext (pC) buffer

 @param[in] pMac  four-byte Message Authentication Code

 @param[in] Mode  EAX_MODE_CLEARTEXT_AUTH or EAX_MODE_CIPHERTEXT_AUTH

 @return    true if message has been authenticated; false if not

      authenticated, invalid Mode or error

 */

WS_DLL_PUBLIC

bool Eax_Decrypt(uint8_t *pN, uint8_t *pK, uint8_t *pC,

                 uint32_t SizeN, uint32_t SizeK, uint32_t SizeC, MAC_T *pMac,

     uint8_t Mode);

#endif