vb.net AES 解密returns "data is incomplete block"
vb.net AES decryption returns "data is incomplete block"
我知道关于这个问题的另一个话题 (AES decryption error " The input data is not a complete block." Error vb.net)，但我要么没有正确实施那里提供的解决方案，要么没有涵盖我对这个问题的特定变体通过这些解决方案。无论如何，我从以下代码中得到了不完整的块错误
Private GD As System.Security.Cryptography.Aes = System.Security.Cryptography.Aes.Create
Private PDB As New System.Security.Cryptography.Rfc2898DeriveBytes(EK, New Byte() {&H49, &H76, &H61, &H6E, &H20, &H4D, &H65, &H64, &H76, &H65, &H64, &H65, &H76})
Public Function Decrypt(ByVal val As String) As String
Dim ret As String = Nothing
Dim TTB As New System.Text.UTF8Encoding
Try
Dim input() As Byte = TTB.GetBytes(val)
Using ms As New System.IO.MemoryStream(input)
Using cs As New System.Security.Cryptography.CryptoStream(ms, GD.CreateDecryptor(PDB.GetBytes(32), PDB.GetBytes(16)), Security.Cryptography.CryptoStreamMode.Read)
Using sr As New System.IO.StreamReader(cs)
ret = sr.ReadToEnd()
End Using
End Using
End Using
input = nothing
Catch ex As Exception
EL.AddErr("Encountered an error while decrypting the provided text for " & FName & ". Error Details: " & ex.Message, path)
End Try
Return ret
End Function
EK 是我的密钥，我不会包括在内。不过它只是一个字符串，没什么特别的。
我已经根据 MSDN 站点、DreamInCode 等上的指导尝试了其他几种解密方法。None 有效，但它们都有不同的问题（通常返回空白字符串）。鉴于此版本的代码与我的加密代码非常相似，我想坚持使用它（或者至少在仍然具有功能代码的情况下尽可能接近）。
尽管有很多评论，但我仍然不了解您的意图。因此，下面的示例代码可能无法提供您真正想要的，但至少应该让您了解如何使用加密函数。特别是，与您的方法最显着的区别是，加密密钥和初始化向量是为所有消息一次性计算的，而不是每次都重新计算，因为后者容易出现同步错误——例如当您重用单个加密对象来与多方通信，或某些消息在传输过程中丢失。
Public Shared Sub Test()
' Note: You should not actually hard-code any sensitive information in your source files, ever!
Dim sKeyPreimage As String = "MySuperPassword"
Dim oMyCrypto As New MyCrypto(sKeyPreimage)
Dim sPlaintext As String = "My super secret data"
Dim sEncrypted As String = oMyCrypto.EncryptText(sPlaintext)
Dim sDecrypted As String = oMyCrypto.DecryptText(sEncrypted)
Console.Out.WriteLine("Plaintext: {0}", sPlaintext) ' "My super secret data"
Console.Out.WriteLine("Encrypted: {0}", sEncrypted) ' "72062997872DC4B4D1BCBF48D5D30DF0D498B20630CAFA28D584CCC3030FC5F1"
Console.Out.WriteLine("Decrypted: {0}", sDecrypted) ' "My super secret data"
End Sub
Public Class MyCrypto
Private Shared TextEncoding As Text.Encoding = Text.Encoding.UTF8
Private CipherEngine As System.Security.Cryptography.SymmetricAlgorithm
' Note: Unlike in the question, same key and IV are reused for all messages.
Private CipherKey() As Byte
Private CipherIV() As Byte
Public Sub New(ByVal sKeyPreimage As String)
Dim abKeyPreimage() As Byte = TextEncoding.GetBytes(sKeyPreimage)
Dim abKeySalt() As Byte = TextEncoding.GetBytes("Ivan Medvedev")
Const KeyDerivationRounds As Integer = 1 << 12
Dim oKeyDerivationEngine As New System.Security.Cryptography.Rfc2898DeriveBytes(abKeyPreimage, abKeySalt, KeyDerivationRounds)
Me.CipherEngine = System.Security.Cryptography.Aes.Create()
Me.CipherEngine.Padding = Security.Cryptography.PaddingMode.PKCS7
Me.CipherKey = oKeyDerivationEngine.GetBytes(Me.CipherEngine.KeySize >> 3)
Me.CipherIV = oKeyDerivationEngine.GetBytes(Me.CipherEngine.BlockSize >> 3)
End Sub
Public Function Encrypt(ByVal abPlaintext() As Byte) As Byte()
Dim abCiphertext() As Byte
Using hStreamSource As New System.IO.MemoryStream(abPlaintext),
hStreamCipher As New System.Security.Cryptography.CryptoStream(
hStreamSource,
Me.CipherEngine.CreateEncryptor(Me.CipherKey, Me.CipherIV),
Security.Cryptography.CryptoStreamMode.Read),
hStreamTarget As New System.IO.MemoryStream
hStreamCipher.CopyTo(hStreamTarget)
abCiphertext = hStreamTarget.ToArray()
End Using
Return abCiphertext
End Function
Public Function Decrypt(ByVal abCiphertext() As Byte) As Byte()
Dim abPlaintext() As Byte
Using hStreamSource As New System.IO.MemoryStream(abCiphertext),
hStreamCipher As New System.Security.Cryptography.CryptoStream(
hStreamSource,
Me.CipherEngine.CreateDecryptor(Me.CipherKey, Me.CipherIV),
Security.Cryptography.CryptoStreamMode.Read),
hStreamTarget As New System.IO.MemoryStream
hStreamCipher.CopyTo(hStreamTarget)
abPlaintext = hStreamTarget.ToArray()
End Using
Return abPlaintext
End Function
Public Function EncryptText(ByVal sPlaintext As String) As String
Dim abPlaintext() As Byte = TextEncoding.GetBytes(sPlaintext)
Dim abCiphertext() As Byte = Me.Encrypt(abPlaintext)
Dim sCiphertext As String = Hex.Format(abCiphertext)
Return sCiphertext
End Function
Public Function DecryptText(ByVal sCiphertext As String) As String
Dim abCiphertext() As Byte = Hex.Parse(sCiphertext)
Dim abPlaintext() As Byte = Me.Decrypt(abCiphertext)
Dim sPlaintext As String = TextEncoding.GetChars(abPlaintext)
Return sPlaintext
End Function
End Class
Public Class Hex
Public Shared Function Format(ByVal abValue() As Byte) As String
Dim asChars(0 To abValue.Length * 2 - 1) As Char
Dim ndxChar As Integer = 0
For ndxByte As Integer = 0 To abValue.Length - 1
Dim bNibbleHi As Byte = abValue(ndxByte) >> 4, bNibbleLo As Byte = CByte(abValue(ndxByte) And &HFUS)
asChars(ndxChar) = Convert.ToChar(If(bNibbleHi <= 9, &H30US + bNibbleHi, &H37US + bNibbleHi)) : ndxChar += 1
asChars(ndxChar) = Convert.ToChar(If(bNibbleLo <= 9, &H30US + bNibbleLo, &H37US + bNibbleLo)) : ndxChar += 1
Next
Return New String(asChars)
End Function
Public Shared Function Parse(ByVal sValue As String) As Byte()
If String.IsNullOrEmpty(sValue) Then Return New Byte() {}
If (sValue.Length Mod 2) > 0 Then Return Nothing
Dim ndxText As Integer = 0
Dim ndxByteMax As Integer = (sValue.Length \ 2) - 1
Dim abValue(0 To ndxByteMax) As Byte
Try
For ndxByte As Integer = 0 To ndxByteMax
abValue(ndxByte) = Convert.ToByte(sValue.Substring(ndxText, 2), 16)
ndxText += 2
Next
Catch ex As Exception
Return Nothing
End Try
Return abValue
End Function
End Class
再次请注意，这只是一个示例。我不赞成此处显示的任何类型的保护技术，尤其是因为您的任务仍然未知。上面的代码只是说明了语法和语义——而不是如何正确地做。
我知道关于这个问题的另一个话题 (AES decryption error " The input data is not a complete block." Error vb.net)，但我要么没有正确实施那里提供的解决方案，要么没有涵盖我对这个问题的特定变体通过这些解决方案。无论如何，我从以下代码中得到了不完整的块错误
Private GD As System.Security.Cryptography.Aes = System.Security.Cryptography.Aes.Create
Private PDB As New System.Security.Cryptography.Rfc2898DeriveBytes(EK, New Byte() {&H49, &H76, &H61, &H6E, &H20, &H4D, &H65, &H64, &H76, &H65, &H64, &H65, &H76})
Public Function Decrypt(ByVal val As String) As String
Dim ret As String = Nothing
Dim TTB As New System.Text.UTF8Encoding
Try
Dim input() As Byte = TTB.GetBytes(val)
Using ms As New System.IO.MemoryStream(input)
Using cs As New System.Security.Cryptography.CryptoStream(ms, GD.CreateDecryptor(PDB.GetBytes(32), PDB.GetBytes(16)), Security.Cryptography.CryptoStreamMode.Read)
Using sr As New System.IO.StreamReader(cs)
ret = sr.ReadToEnd()
End Using
End Using
End Using
input = nothing
Catch ex As Exception
EL.AddErr("Encountered an error while decrypting the provided text for " & FName & ". Error Details: " & ex.Message, path)
End Try
Return ret
End Function
EK 是我的密钥，我不会包括在内。不过它只是一个字符串，没什么特别的。
我已经根据 MSDN 站点、DreamInCode 等上的指导尝试了其他几种解密方法。None 有效，但它们都有不同的问题（通常返回空白字符串）。鉴于此版本的代码与我的加密代码非常相似，我想坚持使用它（或者至少在仍然具有功能代码的情况下尽可能接近）。
尽管有很多评论，但我仍然不了解您的意图。因此，下面的示例代码可能无法提供您真正想要的，但至少应该让您了解如何使用加密函数。特别是，与您的方法最显着的区别是，加密密钥和初始化向量是为所有消息一次性计算的，而不是每次都重新计算，因为后者容易出现同步错误——例如当您重用单个加密对象来与多方通信，或某些消息在传输过程中丢失。
Public Shared Sub Test()
' Note: You should not actually hard-code any sensitive information in your source files, ever!
Dim sKeyPreimage As String = "MySuperPassword"
Dim oMyCrypto As New MyCrypto(sKeyPreimage)
Dim sPlaintext As String = "My super secret data"
Dim sEncrypted As String = oMyCrypto.EncryptText(sPlaintext)
Dim sDecrypted As String = oMyCrypto.DecryptText(sEncrypted)
Console.Out.WriteLine("Plaintext: {0}", sPlaintext) ' "My super secret data"
Console.Out.WriteLine("Encrypted: {0}", sEncrypted) ' "72062997872DC4B4D1BCBF48D5D30DF0D498B20630CAFA28D584CCC3030FC5F1"
Console.Out.WriteLine("Decrypted: {0}", sDecrypted) ' "My super secret data"
End Sub
Public Class MyCrypto
Private Shared TextEncoding As Text.Encoding = Text.Encoding.UTF8
Private CipherEngine As System.Security.Cryptography.SymmetricAlgorithm
' Note: Unlike in the question, same key and IV are reused for all messages.
Private CipherKey() As Byte
Private CipherIV() As Byte
Public Sub New(ByVal sKeyPreimage As String)
Dim abKeyPreimage() As Byte = TextEncoding.GetBytes(sKeyPreimage)
Dim abKeySalt() As Byte = TextEncoding.GetBytes("Ivan Medvedev")
Const KeyDerivationRounds As Integer = 1 << 12
Dim oKeyDerivationEngine As New System.Security.Cryptography.Rfc2898DeriveBytes(abKeyPreimage, abKeySalt, KeyDerivationRounds)
Me.CipherEngine = System.Security.Cryptography.Aes.Create()
Me.CipherEngine.Padding = Security.Cryptography.PaddingMode.PKCS7
Me.CipherKey = oKeyDerivationEngine.GetBytes(Me.CipherEngine.KeySize >> 3)
Me.CipherIV = oKeyDerivationEngine.GetBytes(Me.CipherEngine.BlockSize >> 3)
End Sub
Public Function Encrypt(ByVal abPlaintext() As Byte) As Byte()
Dim abCiphertext() As Byte
Using hStreamSource As New System.IO.MemoryStream(abPlaintext),
hStreamCipher As New System.Security.Cryptography.CryptoStream(
hStreamSource,
Me.CipherEngine.CreateEncryptor(Me.CipherKey, Me.CipherIV),
Security.Cryptography.CryptoStreamMode.Read),
hStreamTarget As New System.IO.MemoryStream
hStreamCipher.CopyTo(hStreamTarget)
abCiphertext = hStreamTarget.ToArray()
End Using
Return abCiphertext
End Function
Public Function Decrypt(ByVal abCiphertext() As Byte) As Byte()
Dim abPlaintext() As Byte
Using hStreamSource As New System.IO.MemoryStream(abCiphertext),
hStreamCipher As New System.Security.Cryptography.CryptoStream(
hStreamSource,
Me.CipherEngine.CreateDecryptor(Me.CipherKey, Me.CipherIV),
Security.Cryptography.CryptoStreamMode.Read),
hStreamTarget As New System.IO.MemoryStream
hStreamCipher.CopyTo(hStreamTarget)
abPlaintext = hStreamTarget.ToArray()
End Using
Return abPlaintext
End Function
Public Function EncryptText(ByVal sPlaintext As String) As String
Dim abPlaintext() As Byte = TextEncoding.GetBytes(sPlaintext)
Dim abCiphertext() As Byte = Me.Encrypt(abPlaintext)
Dim sCiphertext As String = Hex.Format(abCiphertext)
Return sCiphertext
End Function
Public Function DecryptText(ByVal sCiphertext As String) As String
Dim abCiphertext() As Byte = Hex.Parse(sCiphertext)
Dim abPlaintext() As Byte = Me.Decrypt(abCiphertext)
Dim sPlaintext As String = TextEncoding.GetChars(abPlaintext)
Return sPlaintext
End Function
End Class
Public Class Hex
Public Shared Function Format(ByVal abValue() As Byte) As String
Dim asChars(0 To abValue.Length * 2 - 1) As Char
Dim ndxChar As Integer = 0
For ndxByte As Integer = 0 To abValue.Length - 1
Dim bNibbleHi As Byte = abValue(ndxByte) >> 4, bNibbleLo As Byte = CByte(abValue(ndxByte) And &HFUS)
asChars(ndxChar) = Convert.ToChar(If(bNibbleHi <= 9, &H30US + bNibbleHi, &H37US + bNibbleHi)) : ndxChar += 1
asChars(ndxChar) = Convert.ToChar(If(bNibbleLo <= 9, &H30US + bNibbleLo, &H37US + bNibbleLo)) : ndxChar += 1
Next
Return New String(asChars)
End Function
Public Shared Function Parse(ByVal sValue As String) As Byte()
If String.IsNullOrEmpty(sValue) Then Return New Byte() {}
If (sValue.Length Mod 2) > 0 Then Return Nothing
Dim ndxText As Integer = 0
Dim ndxByteMax As Integer = (sValue.Length \ 2) - 1
Dim abValue(0 To ndxByteMax) As Byte
Try
For ndxByte As Integer = 0 To ndxByteMax
abValue(ndxByte) = Convert.ToByte(sValue.Substring(ndxText, 2), 16)
ndxText += 2
Next
Catch ex As Exception
Return Nothing
End Try
Return abValue
End Function
End Class
再次请注意，这只是一个示例。我不赞成此处显示的任何类型的保护技术，尤其是因为您的任务仍然未知。上面的代码只是说明了语法和语义——而不是如何正确地做。