Encrypt/Decrypt

A while ago I was searching for some code to encrypt/decrypt values for a project in Silverlight. Just going to put the code here so that it may be of help to some poor soul. Following code essentially encrypts using AES. A decrypt function is also added. This is in case one doesn’t want to go the on-way MD5 way.

using System.Security.Cryptography;

using System.Text;

using System.IO;

using System.Diagnostics;
public static string Encrypt(string input)

{

string data = input;

byte[] utfdata = UTF8Encoding.UTF8.GetBytes(data);

byte[] saltBytes = UTF8Encoding.UTF8.GetBytes("addSaltToTaste");

AesManaged aes = new AesManaged();

Rfc2898DeriveBytes rfc = new Rfc2898DeriveBytes("thePassword", saltBytes);

// Setting Encryption parameters

aes.BlockSize = aes.LegalBlockSizes[0].MaxSize;

aes.KeySize = aes.LegalKeySizes[0].MaxSize;

aes.Key = rfc.GetBytes(aes.KeySize / 8);

aes.IV = rfc.GetBytes(aes.BlockSize / 8);

// Start Encryption

ICryptoTransform encryptTransf = aes.CreateEncryptor();

MemoryStream encryptStream = new MemoryStream();

CryptoStream encryptor = new CryptoStream(encryptStream, encryptTransf, CryptoStreamMode.Write);

encryptor.Write(utfdata, 0, utfdata.Length);

encryptor.Flush();

encryptor.Close();

// Output Encrypted Content

byte[] encryptBytes = encryptStream.ToArray();

string encryptedString = Convert.ToBase64String(encryptBytes);

Debug.WriteLine(encryptedString);

return encryptedString;

}
private string Decrypt(string base64Input)

{

//byte[] encryptBytes = UTF8Encoding.UTF8.GetBytes(input);

byte[] encryptBytes = Convert.FromBase64String(base64Input);

byte[] saltBytes = Encoding.UTF8.GetBytes("addSaltToTaste");

AesManaged aes = new AesManaged();

Rfc2898DeriveBytes rfc = new Rfc2898DeriveBytes("thePassword", saltBytes);

// Set parameters

aes.BlockSize = aes.LegalBlockSizes[0].MaxSize;

aes.KeySize = aes.LegalKeySizes[0].MaxSize;

aes.Key = rfc.GetBytes(aes.KeySize / 8);

aes.IV = rfc.GetBytes(aes.BlockSize / 8);

// Start decryption

ICryptoTransform decryptTrans = aes.CreateDecryptor();

MemoryStream decryptStream = new MemoryStream();

CryptoStream decryptor = new CryptoStream(decryptStream, decryptTrans, CryptoStreamMode.Write);

decryptor.Write(encryptBytes, 0, encryptBytes.Length);

decryptor.Flush();

decryptor.Close();

// Write decrypted content

byte[] decryptBytes = decryptStream.ToArray();

string decryptedString = UTF8Encoding.UTF8.GetString(decryptBytes, 0, decryptBytes.Length);

//Debug.WriteLine(decryptedString);

return decryptedString;

}