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我的问题实际上比如何在 VB.NET 中使用 AES 要复杂一些，因为我真正想要做的是在 JACOB 的 Java 应用程序中在 VB.NET 中使用 AES。但现在，我需要关注的是 AES 实现本身。

这是我的加密代码

Public Function EncryptAES(ByVal toEncrypt As String, ByVal key As String) As Byte()
    Dim keyArray = Convert.FromBase64String(key)
    Dim toEncryptArray = Encoding.Unicode.GetBytes(toEncrypt)

    Dim aes = New AesCryptoServiceProvider
    aes.Key = keyArray
    aes.Mode = CipherMode.ECB
    aes.Padding = PaddingMode.ISO10126
    Dim encryptor = aes.CreateEncryptor()

    Dim encrypted = encryptor.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length)
    aes.Clear()

    Return encrypted
End Function

回到 Java 代码后，我将字节数组转换为十六进制字符串。

现在，为了扭转这个过程，这是我的解密代码

Public Function DecryptAES(ByVal toDecrypt As String, ByVal key As String) As Byte()
    Dim keyArray = Convert.FromBase64String(key)
    Dim toDecryptArray = Convert.FromBase64String(toDecrypt)

    Dim aes = New AesCryptoServiceProvider
    aes.Key = keyArray
    aes.Mode = CipherMode.ECB
    aes.Padding = PaddingMode.ISO10126
    Dim decryptor = aes.CreateDecryptor()

    Dim decrypted = decryptor.TransformFinalBlock(toDecryptArray, 0, toDecryptArray.Length)
    aes.Clear()
    Return decrypted
End Function

当我运行解密代码时，我收到以下错误消息

填充无效且无法移除。

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1 回答 1

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OK, so there were a couple of things wrong with my original code.

For one, no debugging. I had to add an internal test to verify that my code could encrypt and decrypt before wrapping it in Java. That was silly of me.

Two: the TransformFinalBlock method of both the encryptor and decryptor objects doesn't seem to perform as advertised.

Enough talk. Here's the code

Public Function EncryptAES(ByVal clearText As String, ByVal key As String) As String

    ' prepare input
    Dim keyBytes = Convert.FromBase64String(key)
    Dim sourceBytes = Encoding.Unicode.GetBytes(clearText)

    ' prepare encryption provider
    Dim aes = New AesCryptoServiceProvider
    aes.Key = keyBytes
    aes.Mode = CipherMode.ECB
    aes.Padding = PaddingMode.ISO10126
    Dim encryptor = aes.CreateEncryptor()

    Dim ms = New MemoryStream
    Dim cs = New CryptoStream(ms, encryptor, CryptoStreamMode.Write)
    cs.Write(sourceBytes, 0, sourceBytes.Length)
    cs.FlushFinalBlock()
    Dim encrypted = Convert.ToBase64String(ms.ToArray())

    'Dim decrypted = DecryptAES(encrypted, key)
    'If Not EventLog.SourceExists("CryptoBridge") Then
    '   EventLog.CreateEventSource("CryptoBridge", "CryptoBridge")
    'End If
    'Dim log As New EventLog
    'log.Source = "CryptoBridge"
    'log.WriteEntry(clearText & ":" & decrypted)

    aes.Clear()
    cs.Dispose()
    ms.Dispose()

    Return encrypted
End Function

Public Function DecryptAES(ByVal base64Cipher As String, ByVal key As String) As String
    Dim keyBytes = Convert.FromBase64String(key)
    Dim cipherBytes = Convert.FromBase64String(base64Cipher)

    ' prepare decryption provider
    Dim aes = New AesCryptoServiceProvider
    aes.Key = keyBytes
    aes.Mode = CipherMode.ECB
    aes.Padding = PaddingMode.ISO10126
    Dim decryptor = aes.CreateDecryptor()

    Dim ms = New MemoryStream(cipherBytes)
    Dim cs = New CryptoStream(ms, decryptor, CryptoStreamMode.Read)

    Dim decryptedBytes As Byte()
    ReDim decryptedBytes(cipherBytes.Length)

    Dim readByteCount = cs.Read(decryptedBytes, 0, decryptedBytes.Length)
    Dim decrypted = Encoding.Unicode.GetString(decryptedBytes, 0, readByteCount)

    aes.Clear()
    cs.Dispose()
    ms.Dispose()

    Return decrypted
End Function

Next, I'll be modifying this code to bump up the AES algorithm to 256-bit and CBC cipher mode, which requires an initial vector (IV) value. This adds a level of complexity to the implementation that I wasn't ready to add until the rest worked 100% of the time.

Thanks to all those who commented on my issue.

于 2009-04-07T00:52:54.517 回答