public void AESinCBC_Encrypt_Decrypt_Test() //CBC = Cipher Block Chaining
{
int BLOCKSIZE = 16;
string OriginalMessage = "Now I rock a house party at the drop of a hat\nAnd I beat a body down with an aluminum bat";
var bytes = MyConvert.TextToByteArray(OriginalMessage);
var PaddedBytes = Pad.AddPkcs7(bytes, 128); //Pad the message to 128 bytes
//The Key (16 bytes)
string key = "YELLOW SUBMARINE";
string HexKey = MyConvert.HexEncodePlainText(key);
var Keybytes = MyConvert.HexToByteArray(HexKey);
//Initialization Vector (padded to BLOCKSIZE bytes)
string IVHex = Pad.PadHex(BLOCKSIZE * 2, "00");
var IVBytes = MyConvert.HexToByteArray(IVHex);
//Encrypt
var CiperBytes = MyCrypto.AES_CBC_Encrypt(PaddedBytes, Keybytes, IVBytes, BLOCKSIZE);
//Decrypt
var PlainBytes = MyCrypto.AES_CBC_Decrypt(CiperBytes, Keybytes, IVBytes, BLOCKSIZE);
var UnPaddedBytes = Pad.RemovePkcs7(PlainBytes); //Unpad the message
var hexPlain = MyConvert.BytesToHex(UnPaddedBytes);
var PlainText = MyConvert.HexToAscii(hexPlain);
Assert.IsTrue(OriginalMessage == PlainText);
}
public void PKCS7_Test()
{ //https://en.wikipedia.org/wiki/Padding_(cryptography)#PKCS%235_and_PKCS%237
//https://cryptopals.com/sets/2/challenges/9
string Text = "YELLOW SUBMARINE";
var bytes = MyConvert.TextToByteArray(Text);
var result = Pad.AddPkcs7(bytes, 20);
for (int i = 16; i < 20; i++)
{
Assert.AreEqual(result[i], 4); //four extra bytes, so fill with Hex 04
}
}
public void AESinECB_Encrypt_Decrypt_Test() //ECB = Electronic Codebook
{
string OriginalMessage = "Now is the time for all good men to come to the aid of their country";
var bytes = MyConvert.TextToByteArray(OriginalMessage);
var PaddedBytes = Pad.AddPkcs7(bytes, 128); //Pad the message to 128 bytes
//The Key (16 bytes)
string key = "YELLOW SUBMARINE";
string HexKey = MyConvert.HexEncodePlainText(key);
var Keybytes = MyConvert.HexToByteArray(HexKey);
//Encrypt
var CiperBytes = MyCrypto.AES_ECB_Encrypt(PaddedBytes, Keybytes);
//Decrypt
var PlainBytes = MyCrypto.AES_ECB_Decrypt(CiperBytes, Keybytes);
var UnPaddedBytes = Pad.RemovePkcs7(PlainBytes); //Unpad the message
var hexPlain = MyConvert.BytesToHex(UnPaddedBytes);
var PlainText = MyConvert.HexToAscii(hexPlain);
Assert.IsTrue(OriginalMessage == PlainText);
}