(C# UWP/WinRT) AES XTS Mode

Demonstrates the AES-XTS mode of operation.

Note: This example requires Chilkat v9.5.0.91 or greater.

Chilkat Universal Windows Platform (UWP) / WinRT Downloads Chilkat for the Universal Windows Platform (UWP)

// This example assumes the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

bool success;

// Here we have a sample from CAVS validatition data:

// COUNT = 301
// DataUnitLen = 200
// Key = 
// 394c97881abd989d29c703e48a72b397
// a7acf51b59649eeea9b33274d8541df4
// i = 4b15c684a152d485fe9937d39b168c29
// PT = 2f3b9dcfbae729583b1d1ffdd16bb6fe2757329435662a78f0
// CT = f3473802e38a3ffef4d4fb8e6aa266ebde553a64528a06463e

// Note: The above sample requires an AES-XTS implementation that fully supports ciphertext-stealing
// because the data to be encrypted is not an even multiple of the AES block size (i.e. not a multiple of 16 bytes).
// Chilkat fully supports AES-XTS with ciphertext stealing.
// (i.e. Chilkat implements XEX-based tweaked-codebook mode with ciphertext stealing (XTS))

string key = "394c97881abd989d29c703e48a72b397";
string tweakKey = "a7acf51b59649eeea9b33274d8541df4";
string dataUnit = "4b15c684a152d485fe9937d39b168c29";

Chilkat.BinData bd = new Chilkat.BinData();
bd.AppendEncoded("2f3b9dcfbae729583b1d1ffdd16bb6fe2757329435662a78f0","hex");

Chilkat.Crypt2 crypt = new Chilkat.Crypt2();

crypt.CryptAlgorithm = "aes";
crypt.CipherMode = "xts";
crypt.KeyLength = 128;

crypt.SetEncodedKey(key,"hex");
crypt.XtsSetEncodedTweakKey(tweakKey,"hex");
crypt.XtsSetEncodedTweakValue(dataUnit,"hex");

// In-place encrypt the contents of bd.
success = crypt.EncryptBd(bd);

Debug.WriteLine("CT = " + bd.GetEncoded("hexlower"));

// Decrypt to revert back to the unencrypted content:
success = crypt.DecryptBd(bd);

Debug.WriteLine("PT = " + bd.GetEncoded("hexlower"));

// Output:
// CT = f3473802e38a3ffef4d4fb8e6aa266ebde553a64528a06463e
// PT = 2f3b9dcfbae729583b1d1ffdd16bb6fe2757329435662a78f0