AES加密/解密

Question

下面是一些适用于字符串的代码：

Public Function AESEncrypt(ByVal PlainText As String, ByVal Password As String, ByVal salt As String)
    Dim HashAlgorithm As String = "SHA1" 'Can be SHA1 or MD5
    Dim PasswordIterations As String = 2
    Dim InitialVector As String = "CanEncryption123" 'This should be a string of 16 ASCII characters.
    Dim KeySize As Integer = 256 'Can be 128, 192, or 256.

    If (String.IsNullOrEmpty(PlainText)) Then
        Return ""
        Exit Function
    End If
    Dim InitialVectorBytes As Byte() = Encoding.ASCII.GetBytes(InitialVector)
    Dim SaltValueBytes As Byte() = Encoding.ASCII.GetBytes(salt)
    Dim PlainTextBytes As Byte() = Encoding.UTF8.GetBytes(PlainText)
    Dim DerivedPassword As PasswordDeriveBytes = New PasswordDeriveBytes(Password, SaltValueBytes, HashAlgorithm, PasswordIterations)
    Dim KeyBytes As Byte() = DerivedPassword.GetBytes(KeySize / 8)
    Dim SymmetricKey As RijndaelManaged = New RijndaelManaged()
    SymmetricKey.Mode = CipherMode.CBC

    Dim CipherTextBytes As Byte() = Nothing
    Using Encryptor As ICryptoTransform = SymmetricKey.CreateEncryptor(KeyBytes, InitialVectorBytes)
        Using MemStream As New MemoryStream()
            Using CryptoStream As New CryptoStream(MemStream, Encryptor, CryptoStreamMode.Write)
                CryptoStream.Write(PlainTextBytes, 0, PlainTextBytes.Length)
                CryptoStream.FlushFinalBlock()
                CipherTextBytes = MemStream.ToArray()
                MemStream.Close()
                CryptoStream.Close()
            End Using
        End Using
    End Using
    SymmetricKey.Clear()
    Return Convert.ToBase64String(CipherTextBytes)
End Function
Public Function AESDecrypt(ByVal CipherText As String, ByVal password As String, ByVal salt As String) As String
    Dim HashAlgorithm As String = "SHA1"
    Dim PasswordIterations As String = 2
    Dim InitialVector As String = "CanEncryption123"
    Dim KeySize As Integer = 256

    If (String.IsNullOrEmpty(CipherText)) Then
        Return ""
    End If
    Dim InitialVectorBytes As Byte() = Encoding.ASCII.GetBytes(InitialVector)
    Dim SaltValueBytes As Byte() = Encoding.ASCII.GetBytes(salt)
    Dim CipherTextBytes As Byte() = Convert.FromBase64String(CipherText)
    Dim DerivedPassword As PasswordDeriveBytes = New PasswordDeriveBytes(password, SaltValueBytes, HashAlgorithm, PasswordIterations)
    Dim KeyBytes As Byte() = DerivedPassword.GetBytes(KeySize / 8)
    Dim SymmetricKey As RijndaelManaged = New RijndaelManaged()
    SymmetricKey.Mode = CipherMode.CBC
    Dim PlainTextBytes As Byte() = New Byte(CipherTextBytes.Length - 1) {}

    Dim ByteCount As Integer = 0

    Using Decryptor As ICryptoTransform = SymmetricKey.CreateDecryptor(KeyBytes, InitialVectorBytes)
        Using MemStream As MemoryStream = New MemoryStream(CipherTextBytes)
            Using CryptoStream As CryptoStream = New CryptoStream(MemStream, Decryptor, CryptoStreamMode.Read)
                ByteCount = CryptoStream.Read(PlainTextBytes, 0, PlainTextBytes.Length)
                MemStream.Close()
                CryptoStream.Close()
            End Using
        End Using
    End Using
    SymmetricKey.Clear()
    Return Encoding.UTF8.GetString(PlainTextBytes, 0, ByteCount)
End Function

我可以在修改这些函数以加密/解密字节数组而不是字符串方面提供一些帮助吗？此外，要让函数返回加密/解密的字节数组，而不是字符串。

谢谢

Answer 1

Public Function AESEncrypt(ByVal PlainBytes As Byte, ByVal Password As String, ByVal salt As String)
Dim HashAlgorithm As String = "SHA1" 'Can be SHA1 or MD5
Dim PasswordIterations As String = 2
Dim InitialVector As String = "CanEncryption123" 'This should be a string of 16 ASCII characters.
Dim KeySize As Integer = 256 'Can be 128, 192, or 256.

Dim InitialVectorBytes As Byte() = Encoding.ASCII.GetBytes(InitialVector)
Dim SaltValueBytes As Byte() = Encoding.ASCII.GetBytes(salt)
Dim DerivedPassword As PasswordDeriveBytes = New PasswordDeriveBytes(Password, SaltValueBytes, HashAlgorithm, PasswordIterations)
Dim KeyBytes As Byte() = DerivedPassword.GetBytes(KeySize / 8)
Dim SymmetricKey As RijndaelManaged = New RijndaelManaged()
SymmetricKey.Mode = CipherMode.CBC

Dim CipherTextBytes As Byte() = Nothing
Using Encryptor As ICryptoTransform = SymmetricKey.CreateEncryptor(KeyBytes, InitialVectorBytes)
    Using MemStream As New MemoryStream()
        Using CryptoStream As New CryptoStream(MemStream, Encryptor, CryptoStreamMode.Write)
            CryptoStream.Write(PlainBytes, 0, PlainBytes.Length)
            CryptoStream.FlushFinalBlock()
            CipherTextBytes = MemStream.ToArray()
            MemStream.Close()
            CryptoStream.Close()
        End Using
    End Using
End Using
SymmetricKey.Clear()
Return Convert.ToBase64String(CipherTextBytes)
End Function
Public Function AESDecrypt(ByVal CipherBytes As Byte, ByVal password As String, ByVal salt As String) As String
Dim HashAlgorithm As String = "SHA1"
Dim PasswordIterations As String = 2
Dim InitialVector As String = "CanEncryption123"
Dim KeySize As Integer = 256

If (String.IsNullOrEmpty(CipherText)) Then
    Return ""
End If
Dim InitialVectorBytes As Byte() = Encoding.ASCII.GetBytes(InitialVector)
Dim SaltValueBytes As Byte() = Encoding.ASCII.GetBytes(salt)
Dim DerivedPassword As PasswordDeriveBytes = New PasswordDeriveBytes(password, SaltValueBytes, HashAlgorithm, PasswordIterations)
Dim KeyBytes As Byte() = DerivedPassword.GetBytes(KeySize / 8)
Dim SymmetricKey As RijndaelManaged = New RijndaelManaged()
SymmetricKey.Mode = CipherMode.CBC
Dim PlainTextBytes As Byte() = New Byte(CipherBytes.Length - 1) {}

Dim ByteCount As Integer = 0

Using Decryptor As ICryptoTransform = SymmetricKey.CreateDecryptor(KeyBytes, InitialVectorBytes)
    Using MemStream As MemoryStream = New MemoryStream(CipherBytes)
        Using CryptoStream As CryptoStream = New CryptoStream(MemStream, Decryptor, CryptoStreamMode.Read)
            ByteCount = CryptoStream.Read(PlainTextBytes, 0, PlainTextBytes.Length)
            MemStream.Close()
            CryptoStream.Close()
        End Using
    End Using
End Using
SymmetricKey.Clear()
Return Encoding.UTF8.GetString(PlainTextBytes, 0, ByteCount)
End Function

您使用的代码实际上将输入字符串转换为字节数组。此代码接受字节数组。

Answer 2

我将这个（在 Google 上找到）用于字符串 AES 加密/解密：

Imports System.Security.Cryptography

Namespace TextCrypters

    Public Class AESCrypter

        Public Shared pass As String = "password"

        Public Shared Function AES_Encrypt(ByVal input As String) As String
            Dim AES As New System.Security.Cryptography.RijndaelManaged
            Dim Hash_AES As New System.Security.Cryptography.MD5CryptoServiceProvider
            Dim encrypted As String = ""
            Try
                Dim hash(31) As Byte
                Dim temp As Byte() = Hash_AES.ComputeHash(System.Text.ASCIIEncoding.ASCII.GetBytes(pass))
                Array.Copy(temp, 0, hash, 0, 16)
                Array.Copy(temp, 0, hash, 15, 16)
                AES.Key = hash
                AES.Mode = CipherMode.ECB
                Dim DESEncrypter As System.Security.Cryptography.ICryptoTransform = AES.CreateEncryptor
                Dim Buffer As Byte() = System.Text.ASCIIEncoding.ASCII.GetBytes(input)
                encrypted = Convert.ToBase64String(DESEncrypter.TransformFinalBlock(Buffer, 0, Buffer.Length))
                Return encrypted
            Catch ex As Exception
                Return Nothing
            End Try

        End Function

        Public Shared Function AES_Decrypt(ByVal input As String) As String
            Dim AES As New System.Security.Cryptography.RijndaelManaged
            Dim Hash_AES As New System.Security.Cryptography.MD5CryptoServiceProvider
            Dim decrypted As String = ""
            Try
                Dim hash(31) As Byte
                Dim temp As Byte() = Hash_AES.ComputeHash(System.Text.ASCIIEncoding.ASCII.GetBytes(pass))
                Array.Copy(temp, 0, hash, 0, 16)
                Array.Copy(temp, 0, hash, 15, 16)
                AES.Key = hash
                AES.Mode = CipherMode.ECB
                Dim DESDecrypter As System.Security.Cryptography.ICryptoTransform = AES.CreateDecryptor
                Dim Buffer As Byte() = Convert.FromBase64String(input)
                decrypted = System.Text.ASCIIEncoding.ASCII.GetString(DESDecrypter.TransformFinalBlock(Buffer, 0, Buffer.Length))
                Return decrypted
            Catch ex As Exception
                Return Nothing
            End Try

        End Function

    End Class

End Namespace

要使用它，只需这样做：

Protected Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
    TextBox2.Text = AESCrypter.AES_Encrypt(TextBox1.Text)
End Sub

Protected Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
    TextBox4.Text = AESCrypter.AES_Decrypt(TextBox3.Text)
End Sub

Answer 3

只需将新函数中的所有内容从Dim ByteCount As Integer = 0 复制到SymmetricKey.Clear() 即可删除所有字符串？之后你只需要定义函数的参数。

Answer 4

最简单的方法是使用包装函数，将字节数组转换为字符串，使用AESEncrypt 函数对其进行加密，然后将字符串转换回字节数组。你可以找到VB.net的转换函数here。

编辑添加：我想我弄错了。似乎 VB String 是 Unicode 格式，这些翻译函数将其转换为/从 UTF8 字节数组。这不是我们所需要的……