Vb.net 散列出错了

在登录期间，我使用相同的函数散列值以进行比较，就像在用户注册时散列密码一样：

Public Shared Function Compute(ByVal text As String, ByVal algorithm As String, Optional ByVal salt() As Byte = Nothing) As String
    If salt Is Nothing Then
        Dim saltSize As Integer = 8
        salt = New Byte(saltSize - 1) {}

        Dim rng As New RNGCryptoServiceProvider
        rng.GetNonZeroBytes(salt)
    End If

    Dim textBytes As Byte() = Encoding.UTF8.GetBytes(text)
    Dim saltedTextBytes() As Byte = New Byte(textBytes.Length + salt.Length - 1) {}
    For i As Integer = 0 To textBytes.Length - 1
        saltedTextBytes(i) = textBytes(i)
    Next i

    For i As Integer = 0 To salt.Length - 1
        saltedTextBytes(textBytes.Length + i) = salt(i)
    Next i

    Dim hash As HashAlgorithm
    If algorithm Is Nothing Then
        algorithm = ""
    End If

    Select Case algorithm.ToUpper
        Case "SHA1" : hash = New SHA1Managed
        Case "SHA256" : hash = New SHA256Managed
        Case "SHA384" : hash = New SHA384Managed
        Case "SHA512" : hash = New SHA512Managed
        Case Else : hash = New MD5CryptoServiceProvider
    End Select

    Dim hashBytes As Byte() = hash.ComputeHash(saltedTextBytes)
    Dim saltedHash() As Byte = New Byte(hashBytes.Length + salt.Length - 1) {}
    For i As Integer = 0 To hashBytes.Length - 1
        saltedHash(i) = hashBytes(i)
    Next i

    For i As Integer = 0 To salt.Length - 1
        saltedHash(hashBytes.Length + i) = salt(i)
    Next i

    Dim hashValue As String = Convert.ToBase64String(saltedHash)

    Return Left(hashValue, 36)
End Function

我的问题是，当我尝试登录一个密码被此函数哈希的帐户时，哈希值不匹配。我想我跳过了一步什么的

以下是创建用户帐户的代码：

        ' The email address needs to be valid
        Dim pattern As String = "^(?("")("".+?""@)|(([0-9a-zA-Z]((\.(?!\.))|[-!#\$%&'\*\+/=\?\^`\{\}\|~\w])*)(?<=[0-9a-zA-Z])@))(?(\[)(\[(\d{1,3}\.){3}\d{1,3}\])|(([0-9a-zA-Z][-\w]*[0-9a-zA-Z]\.)+[a-zA-Z]{2,6}))$"
        Dim match As Match = Regex.Match(txtEmail.Text, pattern)
        If match.Success Then
            'Hash the user's password before entering it into the database.
            Dim pass As String = Crypt.Compute(txtPass.Text, "SHA512", Nothing)

            ' Enter the information from the form into the database.
            Dim sql As String = "INSERT INTO Users(Username, Password, EmailAddress) " & _
                "VALUES(@User, @Pass, @Email)"
            Dim cmd As New SqlCommand(sql, conn)
            cmd.Parameters.AddWithValue("@User", txtName.Text)
            cmd.Parameters.AddWithValue("@Pass", pass)
            cmd.Parameters.AddWithValue("@Email", txtEmail.Text)

            conn.Open()
            cmd.ExecuteNonQuery()
            conn.Close()
        Else
            lblError.Text = "Invalid email address. Please correct."
            lblError.ForeColor = Drawing.Color.Red
        End If

”电子邮件地址必须有效
调暗模式为String=“^（？“”（“+？”“@”）（[0-9a-zA-Z]（（\.（？！\））[124；[-！\$%和'\*\+/=\？\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\~\w]）（？）？
通过插入到表中创建帐户时，您使用的用户名是
txtName.Text
，但检查凭据时使用的是
txtser.Text
为什么要使用随机salt？不是每次加密的salt都必须相同吗？我已将您的代码粘贴到一个新项目中，当我为同一密码连续运行两次
Compute
方法时，我会得到两个不同的结果…显然这不起作用。请尝试传递salt值，而不是
Nothing
，一个nd在创建帐户和比较登录时使用相同的salt。以下是一些有效的示例代码：

Dim thePass As String = "MyPassword"
Dim theSalt As String = "salt"

Dim pass As String = Compute(thePass, "SHA512", Encoding.UTF8.GetBytes(theSalt))
Console.WriteLine(pass)
Dim pass2 As String = Compute(thePass, "SHA512", Encoding.UTF8.GetBytes(theSalt))
Console.WriteLine(pass2) 'pass and pass2 are identical


希望这有帮助！
除非我不知道（不太熟悉这门语言），否则你不会把盐放在任何地方

您必须使用创建验证帐户时使用的盐

另一方面：您可以为每个用户帐户生成随机salt，也可以为所有帐户使用固定salt。这两种方法都有效。第一种方法在理论上更安全，但如果salt足够长，两种方法都可以用于实际目的。
否。用户注册和用户登录在不同的页面上处理。这只是控件名这是不同的。我将静态盐的大小设置为8，但仍然没有运气。很好的建议though@Logan：加密和比较之间的salt必须完全相同。不仅仅是静态大小。您不希望salt中有任何随机性，否则密码将永远不匹配。只有在我上次评论后才意识到您的意思。谢谢您的帮助。它不起作用w^^@Logan：另请参阅Dennis的见解文章。如果您想使用随机salt，您必须存储salt，并且您仍然必须确保您使用相同的salt值来比较凭据，就像您最初使用salt密码一样。祝您好运！参考：还有，以及来自它的链接
Dim thePass As String = "MyPassword"
Dim theSalt As String = "salt"

Dim pass As String = Compute(thePass, "SHA512", Encoding.UTF8.GetBytes(theSalt))
Console.WriteLine(pass)
Dim pass2 As String = Compute(thePass, "SHA512", Encoding.UTF8.GetBytes(theSalt))
Console.WriteLine(pass2) 'pass and pass2 are identical