AES 08: AES 128, CBC, PKCS with Frame
This example shows how to encrypt a binary message: - AES algorithm - 128-bit key size - PKCS Padding - CBC Cipher Mode

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 AES_08 Encryption 128 ECB PKCS --------
*
* This example shows how to encrypt a binary message:
* - AES algorithm
* - 128-bit key size
* - PKCS Padding
* - CBC Cipher Mode
*
* 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: Yuri Carmona
*/
#include "WaspAES.h"
#include "WaspFrame.h"
// Define private key to encrypt message
char nodeID[] = "node_001";
// Define a 16-Byte (AES-128) private key to encrypt message
char password[] = "libeliumlibelium";
// Define Initial Vector
uint8_t IV[16] = { 0x00,0x01,0x02,0x03,0x04,0x05,0x06,0x07,0x08,0x09,0x0A,0x0B,0x0C,0x0D,0x0E,0x0F};
// Variable for encrypted message's length
uint16_t encrypted_length;
// 2. Declaration of variable encrypted message with enough memory space
uint8_t encrypted_message[300];
void setup()
{
// init USB port
USB.ON();
USB.println(F("AES_08 example:"));
USB.println(F("- 128-bit Key Size"));
USB.println(F("- ECB Cipher Mode"));
USB.println(F("- PKCS5 padding"));
USB.println();
// set the node ID
frame.setID(nodeID);
}
void loop()
{
////////////////////////////////////////////////
// 1. Create a new Frame
////////////////////////////////////////////////
USB.println(F("1. Creating an ASCII frame"));
RTC.ON();
// Create new frame (ASCII)
frame.createFrame(ASCII);
// set frame fields (String - char*)
frame.addSensor(SENSOR_STR, (char*) "this_is_a_message");
// set frame fields (Battery sensor - uint8_t)
frame.addSensor(SENSOR_BAT, (uint8_t) PWR.getBatteryLevel());
// set frame fields (Temperature in Celsius sensor - float)
frame.addSensor(SENSOR_IN_TEMP, (float) RTC.getTemperature());
// Prints frame
frame.showFrame();
USB.println();
////////////////////////////////////////////////
// 2. Encrypt Frame
////////////////////////////////////////////////
USB.println(F("2. Encrypting Frame"));
// 2.1. Calculate length in Bytes of the encrypted message
encrypted_length = AES.sizeOfBlocks(frame.length);
// 2.2. Calculate encrypted message with ECB cipher mode and PKCS5 padding.
AES.encrypt( 128
, password
, frame.buffer
, frame.length
, encrypted_message
, CBC
, PKCS5
, IV);
// 2.3. Printing encrypted message
USB.print(F("AES Encrypted message:"));
AES.printMessage( encrypted_message, encrypted_length);
// 2.4. Printing encrypted message's length
USB.print(F("AES Encrypted length:"));
USB.println( (int)encrypted_length);
USB.println();
delay(10000);
USB.println(F("***********************"));
}

Output

H#
AES_08 example:
- 128-bit Key Size
- ECB Cipher Mode
- PKCS5 padding
1. Creating an ASCII frame
===============================
Current ASCII Frame:
Length: 70
Frame Type: 128
frame (HEX): 3C3D3E800323333837323634353339236E6F64655F3030312330235354523A746869735F69735F615F6D657373616765234241543A363423494E5F54454D503A32302E373523
frame (STR): <=>€#387264539#node_001#0#STR:this_is_a_message#BAT:64#IN_TEMP:20.75#
===============================
2. Encrypting Frame
AES Encrypted message: "5EE419EF3F35475204A7B99FC883B1C755F22DE3F5CEDF0FA4A55F15012E89940B4EC4510E34E63B5F5C2F458C629C9DAC1EF9AEEB1ECC69FF49BEB89B0C021F4190C51A48956ECD961409E2BA2275CA"
AES Encrypted length:80
***********************
1. Creating an ASCII frame
===============================
Current ASCII Frame:
Length: 70
Frame Type: 128
frame (HEX): 3C3D3E800323333837323634353339236E6F64655F3030312331235354523A746869735F69735F615F6D657373616765234241543A363523494E5F54454D503A32302E373523
frame (STR): <=>€#387264539#node_001#1#STR:this_is_a_message#BAT:65#IN_TEMP:20.75#
===============================
2. Encrypting Frame
AES Encrypted message: "5EE419EF3F35475204A7B99FC883B1C77B83C5B263862424E29CDBF75262BA1CF653E7277AC1D00189DDF025B7B00953DCE640F283B7E87C0ED9E18AB56772CCF25610CF90B6C9B05D60E736E321FBA0"
AES Encrypted length:80‌
Last modified 2yr ago
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