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だから、私は単純な暗号化プログラムを作っています、これはアルゴリズムです:

  1. 例:char:a;key:10000
  2. CONTROL 番号 1000 - 97 = 9903 から ASCII 番号を引く
  3. 結果を 16 進数に変換してから文字列に変換します 9903 = 26AF
  4. 16 進数の結果を 2 桁のグループに分割 26, AF
  5. 分割された 16 進値を ASCII 26 = 38 (&) AF = 175 (¯) に変換すると、結果は次のようになります: &¯

問題は、暗号化キーによっては、暗号化結果がすべて摩耗してしまい、復号化機能が機能しない場合があることです (以下のコード)。テストを行ったところ、問題が暗号化機能にあることはわかっていますが、どこにあるのかわかりません。コードは次のとおりです。

Option Strict On

Imports System.Numerics

Public Class MainF

    'tick for random keys
    Dim objRandom As New System.Random(CType(System.DateTime.Now.Ticks Mod System.Int32.MaxValue, Integer))   

    Private Function AsciiToChars(ByVal nums As IEnumerable(Of Integer)) As Char()
        'converts ASCII value to char
        Return (From c In nums Select Chr(c)).ToArray
    End Function

    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load

        'set random key
        KeyE.Text = CStr(GetRandomNumber(10000, 99999))
        KeyD.Text = KeyE.Text
    End Sub

    Public Function GetRandomNumber(Optional ByVal Low As Integer = 1, Optional ByVal High As Integer = 100) As Integer

        'generate a randomic number, for the random key
        Return objRandom.Next(Low, High + 1)
    End Function

    Private Sub GenKey_Click(sender As Object, e As EventArgs) Handles GenKey.Click

        'renew key
        KeyE.Text = CStr(GetRandomNumber(10000, 99999))
        Dim tmptxt As String
        tmptxt = En.Text
        En.Text = ""
        En.Text = tmptxt
        KeyD.Text = KeyE.Text
        tmptxt = String.Empty
    End Sub

    Sub En_TextChanged(sender As Object, e As EventArgs) Handles En.TextChanged

        'encrypt
        If (String.IsNullOrEmpty(En.Text)) Then
            Enres.Text = ""
        Else
            Dim key As Integer = CInt(KeyE.Text)
            Dim chars() As Char = En.Text.ToCharArray
            Dim ints(chars.Length) As Integer
            Dim hex(chars.Length) As String
            Dim fex As String = ""
            Dim Mlist As New List(Of String)

            For Loop0 As Integer = 0 To chars.Length - 1
                ints(Loop0) = key - Asc(chars(Loop0))
                hex(Loop0) = Conversion.Hex(ints(Loop0))
                fex &= hex(Loop0)
            Next

            If fex.Length Mod 2 <> 0 Then 'Mod returns the remainder of a division calculation. It will be 0 if the number is even.
                fex = "0" & fex 'This will change "6AF" to "06AF"
            End If

            For x As Integer = 0 To fex.Length - 1 Step 2
                Mlist.Add(fex.Substring(x, 2))
            Next

            Dim fdec(CInt((fex.Length - 2) / 2)) As Integer
            Dim fstr As String

            For y As Integer = 0 To fdec.Length - 1
                fdec(y) = CInt(Val("&H" & Mlist(y)))
            Next

            fstr = AsciiToChars(fdec)
            Enres.Text = fstr
        End If
    End Sub

    Private Sub De_TextChanged(sender As Object, e As EventArgs) Handles De.TextChanged

        'decrypt
        If (String.IsNullOrEmpty(De.Text)) Then
            DeRes.Text = ""
        Else
            Dim final As String = ""
            Dim key As Integer
            key = CInt(KeyD.Text)
            Dim FSTR As String = De.Text
            Dim chars() As Char = FSTR.ToCharArray
            Dim hexsub(chars.Length) As String
            Dim ints(chars.Length) As String
            Dim finalhex As String

            For loop1 As Integer = 0 To chars.Length - 1
                ints(loop1) = CStr(Asc(chars(loop1)))
                hexsub(loop1) = Hex(ints(loop1))
            Next          

            finalhex = Join(hexsub, String.Empty)

            If finalhex.Length Mod 4 = 0 Then
                Dim newlist As New List(Of String)

                For x As Integer = 0 To finalhex.Length - 1 Step 4
                    newlist.Add(finalhex.Substring(x, 4))
                Next

                Dim sourceNUM(newlist.Count) As Int32
                Dim finalascii(newlist.Count) As Int32
                Dim finalchar(newlist.Count) As Char
                key = CInt(KeyD.Text)

                For b As Int32 = 0 To newlist.Count - 1
                    sourceNUM(b) = Convert.ToInt32(newlist(b), 16)
                    finalascii(b) = key - sourceNUM(b)

                    If finalascii(b) >= 32 And finalascii(b) <= 255 Then
                        finalchar(b) = Chr(finalascii(b))
                        final &= finalchar(b)
                    Else : final = "Invalid Input"
                    End If
                Next

                DeRes.Text = final
            Else
                DeRes.Text = ""
            End If
        End If
    End Sub

    Private Sub KeyE_TextChanged(sender As Object, e As KeyEventArgs) Handles KeyE.KeyDown

        'future idea, enter key will run encription sub
        If e.KeyCode = Keys.Enter Then
            e.SuppressKeyPress = True
        End If
    End Sub
End Class
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1 に答える 1

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問題は、暗号化キーによっては（以下のコード）、暗号化結果がすべて摩耗してしまい、復号化機能が機能しない場合があることです。

私が見つけることができるあなたの主な問題は、表示できないコードを暗号化された文字列に渡すことがあり、それがnullとして扱われ、復号化アルゴリズムが失敗することです

不適切な値を与えるキーの範囲を把握し、それらのキーを除外するか、文字列の代わりにバイト配列を使用する必要がある場合があります。

于 2013-06-28T07:01:25.473 に答える