vb6和c#中的AES加密

Question

我需要一个.NET (理想情况下是C#)算法,它会产生与vb6我加密和decrypt二进制文件相同的结果.我一直在努力寻找代码一周,但收效甚微.

我开始使用如何加密VB6中的字符串解密VB.NET,但它只是一半的解决方案,它使用RC2而不是AES.在一些摆弄之后,我得到了我的vb6代码,AES但我找不到一种方法c#来产生相同的结果.我认为这与我Key和我的方式有关IV.我一直在浏览加密服务我的尝试可以分为两种基本类型.我努力PasswordDeriveBytes.CryptDeriveKey尝试使用它的地方aes.根本没有成功.尝试模仿它的行为.贝娄我会发布我的vb6代码和我最接近的c#尝试.我不能100%肯定地说这vb6是完美的,所以如果需要做出改变,我会对它持开放态度.我知道有一种方法可以使用p调用,我知道有一种方法可以让.net dll我从我的调用vb apps.我宁愿不这样做.

VB6功能

Public Function Crypt_File(PathToSourceFile As String, PathToDestFile As String, Password As String, HowTo As CryptMethod) As Boolean
Const FName As String = "mdlCryptography.Encrypt_file"
Dim CryptoContext As Long
Dim strProvider As String
Dim HashHnd As Long
Dim CrypKey As Long
Dim Step As Integer
Dim CryptBuff As String
Dim InFileNum As Long, OutFileNum As Long
Dim BytesRemaining As Long, CurrentBufferSize  As Long
Dim MAX_BUFFER_SIZE As Long
Dim DoCryptFinalise As Long
Dim Buff As String
On Error GoTo Trap:
    Step = 10
    Crypt_File = False
    If PathToSourceFile = PathToDestFile Then '
        Err.Raise 334, FName, "Sourse and Dest Path are the same"
    End If
    MAX_BUFFER_SIZE = (2 ^ 20) * 100 '100 MB
    Buff = vbNullChar
    strProvider = MS_ENH_RSA_AES_PROV_A & vbNullChar
    If Not CBool(CryptAcquireContext(CryptoContext, ByVal Buff, ByVal strProvider, PROV_RSA_AES, CRYPT_VERIFYCONTEXT)) Then
        Err.Raise 33410, FName, "Unable to Acquire Context: " & MS_ENH_RSA_AES_PROV_A
    End If

    If Not CBool(CryptCreateHash(CryptoContext, CALG_SHA_256, ByVal 0&, ByVal 0&, HashHnd)) Then
        Err.Raise 33420, FName, "Unable to Create a hash object. " & MS_ENH_RSA_AES_PROV_A
    End If

    If Not CBool(CryptHashData(HashHnd, Password, Len(Password), ByVal 0&)) Then
        Err.Raise 33430, FName, "Unable to Hash password. "
    End If

    If Not CBool(CryptDeriveKey(CryptoContext, CALG_AES_256, HashHnd, ByVal CRYPT_NO_SALT, CrypKey)) Then
        Err.Raise 33440, FName, "Unable to Derive Key. "
    End If
    'Clear HashHnd
    If HashHnd <> 0 Then
        Call CryptDestroyHash(HashHnd)
    End If
    HashHnd = 0

    'Prep Data For encryption
    DoCryptFinalise = 0
    InFileNum = FreeFile
    Step = 20
    Open PathToSourceFile For Binary Access Read As #InFileNum
    If LenB(Dir$(PathToDestFile)) > 0 Then
        Kill PathToDestFile
    End If
    OutFileNum = FreeFile
    Step = 25
    Open PathToDestFile For Binary Access Write As #OutFileNum

    BytesRemaining = LOF(InFileNum)
    'Loop through File Chunks
    Do While BytesRemaining > 0

        If BytesRemaining >= MAX_BUFFER_SIZE Then
            CurrentBufferSize = MAX_BUFFER_SIZE
        Else
            CurrentBufferSize = BytesRemaining
            DoCryptFinalise = 1
        End If

        Buff = String$(CurrentBufferSize, vbNullChar)
        Get #InFileNum, , Buff
            If HowTo = CryptMethod.Encrypt Then
                CryptBuff = EncryptBuffer(CrypKey, DoCryptFinalise, Buff)
            Else
                CryptBuff = DecryptBuffer(CrypKey, DoCryptFinalise, Buff)
            End If
        Put #OutFileNum, , CryptBuff

        BytesRemaining = BytesRemaining - CurrentBufferSize
    Loop
    Close #InFileNum
    Close #OutFileNum
    Crypt_File = True

GoTo Fin
Trap:
    Crypt_File = False
    If Step = 20 Then
        Close #InFileNum
    End If
    If Step = 25 Then
        Close #InFileNum
        Close #OutFileNum
    End If
    Err.Raise Err.Number, Err.source, Err.Description
Fin:

    If CrypKey <> 0 Then
        Call CryptDestroyKey(CrypKey)
    End If
    If HashHnd <> 0 Then
        Call CryptDestroyHash(HashHnd)
    End If
End Function

Private Function EncryptBuffer(CrypKey As Long, DoCryptFinalise As Long, Buff As String) As String
Dim EncDataLength As Long, EnctBuffLen As Long
Dim CryptBuff As String

    EncDataLength = Len(Buff)
    EnctBuffLen = EncDataLength + AES_BLOCK_SIZE
    CryptBuff = String$(EnctBuffLen, vbNullChar)
    LSet CryptBuff = Buff
    If Not CBool(CryptEncrypt(CrypKey, ByVal 0&, ByVal DoCryptFinalise, ByVal 0&, CryptBuff, EncDataLength, EnctBuffLen)) Then
'        Close #InFileNum
'        Close #OutFileNum
        Err.Raise 33450, "mdlCryptography.EncryptBuffer", "Encryption Error"
    End If
    EncryptBuffer = Left$(CryptBuff, EncDataLength)
End Function


Private Function DecryptBuffer(CrypKey As Long, DoCryptFinalise As Long, Buff As String) As String
Dim EncDataLength As Long
Dim CryptBuff As String

    EncDataLength = Len(Buff)
    CryptBuff = String$(EncDataLength, vbNullChar)
    LSet CryptBuff = Buff
    If Not CBool(CryptDecrypt(CrypKey, ByVal 0&, ByVal DoCryptFinalise, ByVal 0&, CryptBuff, EncDataLength)) Then
'        Close #InFileNum
'        Close #OutFileNum
        Err.Raise 33450, "mdlCryptography.DecryptBuffer", "Decryption Error"
    End If
    DecryptBuffer = Left$(CryptBuff, EncDataLength)
End Function

c#这是非常未定义的

private void Crypt(bool DoEn)
{
    int Rfc2898KeygenIterations = 100;
    int AesKeySizeInBits = 128;
    byte[] rawPlaintext ;//= System.Text.Encoding.Unicode.GetBytes("This is all clear now!");
    byte[] cipherText = null;
    byte[] plainText = null;

    using (Aes aes = new AesManaged())
    {

        int KeyStrengthInBytes = aes.KeySize / 8;

        SHA256 MySHA = new SHA256Cng();
        MySHA.Initialize();
        plainText = Encoding.ASCII.GetBytes(txtPassword.Text);
        aes.Key = MySHA.ComputeHash(plainText );
        aes.IV =  Encoding.ASCII.GetBytes("0000000000000000");
        if (DoEn)
        {
            //using (FileStream fs = new FileStream(txtOut.Text,FileMode.CreateNew ))
            using (MemoryStream ms = new MemoryStream())
            {
                using (CryptoStream cs = new CryptoStream(ms, aes.CreateEncryptor(), CryptoStreamMode.Write))
                {
                    //using (StreamReader myFile = new StreamReader(txtIn.Text))
                    //{
                    //    rawPlaintext = System.Text.Encoding.ASCII.GetBytes(myFile.ReadToEnd());
                        rawPlaintext = File.ReadAllBytes(txtIn.Text);
                        cs.Write(rawPlaintext, 0, rawPlaintext.Length);

                    //}
                }
                cipherText = ms.ToArray();
                File.WriteAllBytes(txtOut.Text, cipherText);
            }
        }
        else
        {
            //using (FileStream fs = new FileStream(txtIn.Text, FileMode.CreateNew))
            using (MemoryStream ms = new MemoryStream())
            {
                using (CryptoStream cs = new CryptoStream(ms, aes.CreateDecryptor(), CryptoStreamMode.Write))
                {
                    //using (StreamReader myFile = new StreamReader(txtOut.Text))
                    //{
                        //string s = myFile.r.ReadToEnd();
                        rawPlaintext = File.ReadAllBytes(txtOut.Text); //System.Text.Encoding.ASCII.GetBytes(s);
                        //cipherText = new int[rawPlaintext.Length];
                        cs.Write(rawPlaintext, 0, rawPlaintext.Length);
                        //cs.Write(cipherText, 0, cipherText.Length);
                    //}
                }
                cipherText = ms.ToArray();
                File.WriteAllBytes(txtIn.Text, cipherText);
            }
        }
    }
    //string s = System.Text.Encoding.ASCII.GetString(plainText);
    //Console.WriteLine(s);
}

Answer 1

在我看来,在VB6示例中,您指定了CRYPT_NO_SALT,我相信这会导致使用无初始化向量.据推测,这都是零,但我不确定.

但是在C#代码中,您获取ASCII文本"0000000000000000"的字节,这与字符号{0,0,0,0,... 0}的字节数组不同,因为字符"0"是等于ASCII中的数字48(参见:http://www.asciitable.com/).我认为这可能是你问题的根源.