This example shows how to calculate SHA-224 message digest to provide INTEGRITY to the sending of information. Both data must be sent over the network: MESSAGE + HASH_MESSAGE
Required Materials
1 x Waspmote
1 x Battery
Notes
- The battery has to be connected.
- This example can be executed in Waspmote v12 and Waspmote v15
Code
/*
* ------Waspmote HASH_03 SHA-224 Message Digest--------
*
* This example shows how to calculate SHA-224 message digest to
* provide INTEGRITY to the sending of information. Both data
* must be sent over the network: MESSAGE + HASH_MESSAGE
*
* Copyright (C) 2016 Libelium Comunicaciones Distribuidas S.L.
* http://www.libelium.com
*
* 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, see <http://www.gnu.org/licenses/>.
*
* Version: 3.0
* Design: David Gascón
* Implementation: Alvaro Gonzalez, Yuri Carmona
*/
#include "WaspHash.h"
// Original message
char message[] = "Libelium";
// Variable to store the hash message
uint8_t hash_message_sha224[28];
void setup()
{
USB.ON();
USB.println(F("HASH_03 example"));
USB.println(F("- SHA-224 algorithm"));
USB.println(F("- Message Digest length of 224 bits (28 Bytes)"));
USB.println();
USB.print(F("Original message: "));
USB.println(message);
}
void loop()
{
// Calculate hash of original message with SHA-224 Algorithm
HASH.sha( SHA224, hash_message_sha224, (uint8_t*)message, strlen(message)*8);
// Printing message digest SHA-224
HASH.printMessageDigest("SHA-224:", hash_message_sha224 , 28);
delay(5000);
}
Output
H#
HASH_03 example
- SHA-224 algorithm
- Message Digest length of 224 bits (28 Bytes)
Original message: Libelium
SHA-224:"29A0CCCB235730C96348B029A7E97F088DFBC3C47EB1D45F1B8CACEC"
SHA-224:"29A0CCCB235730C96348B029A7E97F088DFBC3C47EB1D45F1B8CACEC"