AES-DotNet

using System;

using System.Security.Cryptography;

class MainClass {

private static string my_encrypt(string mytext, string key, string iv)

{

byte[] bkey = System.Text.Encoding.UTF8.GetBytes(key);

byte[] biv = System.Text.Encoding.UTF8.GetBytes(iv);

byte[] toEncrypt = System.Text.Encoding.UTF8.GetBytes(mytext);

byte[] cipherBytes = null;

//Possible algorithmName values are: "AES", "AesCryptoServiceProvider", "System.Security.Cryptography.AesCryptoServiceProvider", "AesManaged", and "System.Security.Cryptography.AesManaged".

using (Aes aesAlg = Aes.Create())

{

aesAlg.Mode = CipherMode.CBC;

aesAlg.KeySize = 256;

aesAlg.BlockSize = 128;

aesAlg.Key = bkey;

aesAlg.IV = biv;

using (System.Security.Cryptography.ICryptoTransform transform = aesAlg.CreateEncryptor())

{

using (var mStream = new System.IO.MemoryStream())

{

using (var cStream = new CryptoStream(mStream, transform, CryptoStreamMode.Write))

{

cStream.Write(toEncrypt, 0, toEncrypt.Length);

cStream.FlushFinalBlock();

cipherBytes = mStream.ToArray();

}

}

}

}

return Convert.ToBase64String(cipherBytes);

}

private static string my_decrypt(string mytext, string key, string iv)

{

//decrypt

byte[] bkey = System.Text.Encoding.UTF8.GetBytes(key);

byte[] biv = System.Text.Encoding.UTF8.GetBytes(iv);

byte[] toDecrypt = Convert.FromBase64String(mytext);

string decryptedString = null;

//Possible algorithmName values are: "AES", "AesCryptoServiceProvider", "System.Security.Cryptography.AesCryptoServiceProvider", "AesManaged", and "System.Security.Cryptography.AesManaged".

using (Aes aesAlg = Aes.Create())

{

aesAlg.Mode = CipherMode.CBC;

aesAlg.KeySize = 256;

aesAlg.BlockSize = 128;

aesAlg.Key = bkey;

aesAlg.IV = biv;

using (System.Security.Cryptography.ICryptoTransform transform2 = aesAlg.CreateDecryptor()) // <-- difference here

{

using (var mStream2 = new System.IO.MemoryStream())

{

using (var cStream2 = new CryptoStream(mStream2, transform2, CryptoStreamMode.Write))

{

cStream2.Write(toDecrypt, 0, toDecrypt.Length);

cStream2.FlushFinalBlock();

decryptedString = System.Text.Encoding.Default.GetString(mStream2.ToArray());

}

}

}

}

return decryptedString;

}

static void Main() {

Console.WriteLine("AES 256");

string toEncryptString = "testtesttesttesttest";

string key = "j80o0nywcn0yeapjk0qzh2dw0zw6u0f0"; //must be 32bytes

string iv = "7608kuwtoi436by1"; //must be 16bytes

Console.WriteLine( "text: " + toEncryptString);

Console.WriteLine( "key: " + key);

Console.WriteLine( "iv: " + iv);

string enc = my_encrypt(toEncryptString, key, iv);

Console.WriteLine( "encrypted: " + enc);

Console.WriteLine( "binary encrypted: " + BitConverter.ToString(Convert.FromBase64String(enc)));

string decr = my_decrypt(enc, key, iv);

Console.WriteLine( "decrypted: " + decr);

Console.WriteLine( "binary decrypted: " + BitConverter.ToString(System.Text.Encoding.Default.GetBytes(decr)));

}

}