eive-obsw/gomspace/libcsp/include/csp/crypto/csp_hmac.h
2020-11-23 11:42:22 +01:00

74 lines
2.3 KiB
C

/*
Cubesat Space Protocol - A small network-layer protocol designed for Cubesats
Copyright (C) 2012 GomSpace ApS (http://www.gomspace.com)
Copyright (C) 2012 AAUSAT3 Project (http://aausat3.space.aau.dk)
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef _CSP_HMAC_H_
#define _CSP_HMAC_H_
#include <csp/csp_types.h>
#ifdef __cplusplus
extern "C" {
#endif
#define CSP_HMAC_LENGTH 4
/**
* Append HMAC to packet
* @param packet Pointer to packet
* @param include_header use header in hmac calculation (this will not modify the flags field)
* @return 0 on success, negative on failure
*/
int csp_hmac_append(csp_packet_t * packet, bool include_header);
/**
* Verify HMAC of packet
* @param packet Pointer to packet
* @param include_header use header in hmac calculation (this will not modify the flags field)
* @return 0 on success, negative on failure
*/
int csp_hmac_verify(csp_packet_t * packet, bool include_header);
/**
* Calculate HMAC on buffer
*
* This function is used by append/verify but cal also be called separately.
* @param key HMAC key
* @param keylen HMAC key length
* @param data pointer to data
* @param datalen lehgth of data
* @param hmac output HMAC calculation (CSP_HMAC_LENGTH)
* @return 0 on success, negative on failure
*/
int csp_hmac_memory(const uint8_t * key, uint32_t keylen, const uint8_t * data, uint32_t datalen, uint8_t * hmac);
/**
* Save a copy of the key string for use by the append/verify functions
* @param key HMAC key
* @param keylen HMAC key length
* @return Always returns 0
*/
int csp_hmac_set_key(char * key, uint32_t keylen);
#ifdef __cplusplus
} /* extern "C" */
#endif
#endif // _CSP_HMAC_H_