Crypto CBC library test

// reference https://rweather.github.io/arduinolibs/crypto.html
#include <CBC.h>
#include <AES.h>

#define BLOCK_SIZE 16
CBC<AES128> cbc;
byte key[BLOCK_SIZE] = "_###myKey1234###";
byte iv[BLOCK_SIZE];
byte chiper[BLOCK_SIZE];

void setup() {
  Serial.begin(115200);
  // Set key
  cbc.setKey(key, BLOCK_SIZE);

  // perform test
  for(byte i = 0; i<5; i++){
    Serial.println();
    Serial.print("Run no. ");
    Serial.println(i);
    test_AES128();
  }

}

void loop() {
  // put your main code here, to run repeatedly:

}

// Helper routine to dump a byte array as hex values to Serial.
void printHex(byte *buffer, byte bufferSize) {
  for (byte i = 0; i < bufferSize; i++) {
    Serial.print(buffer[i] < 0x10 ? " 0" : " ");
    Serial.print(buffer[i], HEX);
  }
  Serial.println();
}
void printString(byte *buffer, byte bufferSize) {
  for (byte i = 0; i < bufferSize; i++) {
    Serial.print((char)buffer[i]);
  }
  Serial.println();
}

void test_AES128(){
  long t1, t2 = 0;

  // Print original plain text (just for checking)
  byte plain[] = "0123456789ABCDEF";
  Serial.print("original plain text:");
  printString(plain, sizeof(plain));
  Serial.print("original plain byte:");
  printHex(plain, sizeof(plain));


  // Generate a random initialization vector
  for (int i = 0 ; i < BLOCK_SIZE ; i++ ) {
    iv[i]= random(0xFF);
  }

  // Set initialization vector
  t1 = micros();
  cbc.setIV(iv, BLOCK_SIZE);
  t2 = micros() - t1;
  Serial.print(t2);
  Serial.print(" uS - IV:");
  printHex(iv, sizeof(iv));

  // encrypt
  t1 = micros();
  cbc.encrypt(chiper, plain, BLOCK_SIZE);
  t2 = micros() - t1;
  Serial.print(t2);
  Serial.print(" uS - encrypted chiper:");
  printHex(chiper, sizeof(chiper));

  // decrypt
  t1 = micros();
  cbc.decrypt(chiper, plain, BLOCK_SIZE);
  t2 = micros() - t1;
  Serial.print(t2);
  Serial.print(" uS - decrypted plain:");
  printHex(plain, sizeof(plain));

  cbc.clear();
}