Question:You are developing a method to encrypt sensitive data with the Data Encryption Standard (DES) algorithm. Your method accepts the following parameters:
The byte array to be encrypted, which is named message
An encryption key, which is named key
An initialization vector, which is named iv
You need to encrypt the data. You also need to write the encrypted data to a MemoryStream object.
Which code segment should you use?
A Dim objDES As New DESCryptoServiceProvider
objDES.BlockSize = message.Length
Dim objCrypto As ICryptoTransform = objDES.CreateDecryptor(key, iv) Dim cipherStream As New MemoryStream
Dim cryptoStream As New CryptoStream(cipherStream, objCrypto, CryptoStreamMode.Write)
B Dim objDES As New DESCryptoServiceProvider
Dim objCrypto As ICryptoTransform = objDES.CreateDecryptor(key, iv) Dim cipherStream As New MemoryStream
Dim cryptoStream As New CryptoStream(cipherStream, objCrypto, CryptoStreamMode.Write) cryptoStream.Write(message, 0, message.Length)
C Dim objDES As New DESCryptoServiceProvider
Dim objCrypto As ICryptoTransform = objDES.CreateEncryptor(key, iv) Dim cipherStream As New MemoryStream
Dim cryptoStream As New CryptoStream(cipherStream, objCrypto, CryptoStreamMode.Write) cryptoStream.Write(message, 0, message.Length)
D Dim objDES As New DESCryptoServiceProvider
Dim objCrypto As ICryptoTransform = objDES.CreateDecryptor() Dim cipherStream As New
MemoryStream
Dim cryptoStream As New CryptoStream(cipherStream, objCrypto, CryptoStreamMode.Write) cryptoStream.Write(message, 0, message.Length)