我正在尝试让 rijndael 在 CBC 模式下工作。我不完全确定我应该怎么做。我认为我当前代码中的问题是每次在加密开始时都会初始化流,因此不会发生雪崩效应(相同的数据被加密两次,并且这两次加密的输出是相同的,它不应该是)。
我尝试只初始化一次加密流,但随后我的编码崩溃了,因为加密流的 canwrite 属性在第一次写入加密流后变为 false。
这是我现在拥有的代码:
Sub Main()
Dim rij As New RijndaelManaged
Dim iv(15) As Byte
Dim key(15) As Byte
Dim secret() As Byte = {59, 60, 61}
Dim cs As ICryptoTransform
Dim cstream As CryptoStream
Dim out() As Byte
Dim NewRandom As New RNGCryptoServiceProvider()
NewRandom.GetBytes(iv)
NewRandom.GetBytes(key)
rij = New RijndaelManaged()
rij.KeySize = 128
rij.Padding = PaddingMode.PKCS7
rij.Mode = CipherMode.CBC
rij.IV = iv
rij.Key = key
cs = rij.CreateEncryptor()
Dim ms_in As New MemoryStream
cstream = New CryptoStream(ms_in, cs, CryptoStreamMode.Write)
Using cstream
cstream.Write(secret, 0, 3)
End Using
out = ms_in.ToArray
Console.WriteLine(ArrayToString(out, out.Length))
Erase out
ms_in = New MemoryStream
cstream = New CryptoStream(ms_in, cs, CryptoStreamMode.Write)
Using cstream
cstream.Write(secret, 0, 3)
End Using
out = ms_in.ToArray
Console.WriteLine(ArrayToString(out, out.Length))
End Sub
以及将数组转换为字符串的转换函数
Public Function ArrayToString(ByVal bytes() As Byte, ByVal length As Integer) As String
If bytes.Length = 0 Then Return String.Empty
Dim sb As New System.Text.StringBuilder(length)
Dim k As Integer = length - 1
Dim i As Integer
For i = 0 To k
sb.Append(Chr(bytes(i)))
Next
Return sb.ToString()
End Function
这就是我需要的:
cs = rij.CreateEncryptor()
Dim ms_in As New MemoryStream
cstream = New CryptoStream(ms_in, cs, CryptoStreamMode.Write)
Using cstream
cstream.Write(secret, 0, 3) 'encrypt
End Using
out = ms_in.ToArray
Console.WriteLine(ArrayToString(out, out.Length)) 'see the encrypted message
Erase out
Using cstream
cstream.Write(secret, 0, 3) 'encrypt, this will crash here and this is the problem I'm trying to solve
End Using
out = ms_in.ToArray
Console.WriteLine(ArrayToString(out, out.Length)) 'see the encrypted message this should not be the same as the first one