Hayırlı sabahlar
shift ile kilitlense bile onuda kıran programlar olduğuna göre programa giriş şifrelerini Access içinde bir tabloda tutmak ne kadar mantıklı
md5 ile tek yönlü şifre oluşturarak bu değeri tabloda tutarsak en azında runtime tablolarda değişiklik yapamasınlar göremesinler
ama illaki bir şekilde Access tabloları görülebiliyor
işin md5 kısmı basit ama şifre sıfırlama maili attırabilir miyiz. 
Mail gönderilmesi ile ilgili örnekler vardı diye hatırlıyorum.bunu da hallettik diyelim
mail geldi bizde maile girdik ve linki tıkladık bu açılan pencerden yeni şifre de girdik diyelim
bu yeni şifre ile programa girmek için programda şifre kısmında bir değerin değişmesi lazım değil mi
bunu nasıl halledeceğiz

md5 şifresi oluşturan kod şudur


Public Function MD5(ByVal sIn As String, Optional bB64 As Boolean = 0) As String
    'Set a reference to mscorlib 4.0 64-bit
   
    'Test with empty string input:
    'Hex:  d41d8cd98f00...etc
    'Base-64: 1B2M2Y8Asg...etc
       
    Dim oT As Object, oMD5 As Object
    Dim TextToHash() As Byte
    Dim bytes() As Byte
       
    Set oT = CreateObject("System.Text.UTF8Encoding")
    Set oMD5 = CreateObject("System.Security.Cryptography.MD5CryptoServiceProvider")

    TextToHash = oT.Getbytes_4(sIn)
    bytes = oMD5.ComputeHash_2((TextToHash))

    If bB64 = True Then
      MD5 = ConvToBase64String(bytes)
    Else
      MD5 = ConvToHexString(bytes)
    End If
       
    Set oT = Nothing
    Set oMD5 = Nothing

End Function

Merhaba arkadaşlar,
bu MD5 nasıl kullanılıyor, açıklarsanız sevinirim.

Şifre = MD5(Şifre)

Hocam dediğiniz gibi yaptım aşağıdaki hatayı alıyorum, neden acaba?

şunlarıda ekleyin



Public Function SHA1(sIn As String, Optional bB64 As Boolean = 0) As String
    'Set a reference to mscorlib 4.0 64-bit
   
    'Test with empty string input:
    '40 Hex:  da39a3ee5e6...etc
    '28 Base-64:  2jmj7l5rSw0yVb...etc
   
    Dim oT As Object, oSHA1 As Object
    Dim TextToHash() As Byte
    Dim bytes() As Byte
           
    Set oT = CreateObject("System.Text.UTF8Encoding")
    Set oSHA1 = CreateObject("System.Security.Cryptography.SHA1Managed")
   
    TextToHash = oT.Getbytes_4(sIn)
    bytes = oSHA1.ComputeHash_2((TextToHash))
       
    If bB64 = True Then
      SHA1 = ConvToBase64String(bytes)
    Else
      SHA1 = ConvToHexString(bytes)
    End If
           
    Set oT = Nothing
    Set oSHA1 = Nothing
   
End Function

Public Function SHA256(sIn As String, Optional bB64 As Boolean = 0) As String
    'Set a reference to mscorlib 4.0 64-bit
   
    'Test with empty string input:
    '64 Hex:  e3b0c44298f...etc
    '44 Base-64:  47DEQpj8HBSa+/...etc
   
    Dim oT As Object, oSHA256 As Object
    Dim TextToHash() As Byte, bytes() As Byte
   
    Set oT = CreateObject("System.Text.UTF8Encoding")
    Set oSHA256 = CreateObject("System.Security.Cryptography.SHA256Managed")
   
    TextToHash = oT.Getbytes_4(sIn)
    bytes = oSHA256.ComputeHash_2((TextToHash))
   
    If bB64 = True Then
      SHA256 = ConvToBase64String(bytes)
    Else
      SHA256 = ConvToHexString(bytes)
    End If
   
    Set oT = Nothing
    Set oSHA256 = Nothing
   
End Function

Public Function SHA384(sIn As String, Optional bB64 As Boolean = 0) As String
    'Set a reference to mscorlib 4.0 64-bit
   
    'Test with empty string input:
    '96 Hex:  38b060a751ac...etc
    '64 Base-64:  OLBgp1GsljhM2T...etc
   
    Dim oT As Object, oSHA384 As Object
    Dim TextToHash() As Byte, bytes() As Byte
   
    Set oT = CreateObject("System.Text.UTF8Encoding")
    Set oSHA384 = CreateObject("System.Security.Cryptography.SHA384Managed")
   
    TextToHash = oT.Getbytes_4(sIn)
    bytes = oSHA384.ComputeHash_2((TextToHash))
   
    If bB64 = True Then
      SHA384 = ConvToBase64String(bytes)
    Else
      SHA384 = ConvToHexString(bytes)
    End If
   
    Set oT = Nothing
    Set oSHA384 = Nothing
   
End Function

Public Function SHA512(sIn As String, Optional bB64 As Boolean = 0) As String
    'Set a reference to mscorlib 4.0 64-bit
   
    'Test with empty string input:
    '128 Hex:  cf83e1357eefb8bd...etc
    '88 Base-64:  z4PhNX7vuL3xVChQ...etc
   
    Dim oT As Object, oSHA512 As Object
    Dim TextToHash() As Byte, bytes() As Byte
   
    Set oT = CreateObject("System.Text.UTF8Encoding")
    Set oSHA512 = CreateObject("System.Security.Cryptography.SHA512Managed")
   
    TextToHash = oT.Getbytes_4(sIn)
    bytes = oSHA512.ComputeHash_2((TextToHash))
   
    If bB64 = True Then
      SHA512 = ConvToBase64String(bytes)
    Else
      SHA512 = ConvToHexString(bytes)
    End If
   
    Set oT = Nothing
    Set oSHA512 = Nothing
   
End Function

Function StrToSHA512Salt(ByVal sIn As String, ByVal sSecretKey As String, _
                          Optional ByVal b64 As Boolean = False) As String
    'Returns a sha512 STRING HASH in function name, modified by the parameter sSecretKey.
    'This hash differs from that of SHA512 using the SHA512Managed class.
    'HMAC class inputs are hashed twice;first input and key are mixed before hashing,
    'then the key is mixed with the result and hashed again.
   
    Dim asc As Object, enc As Object
    Dim TextToHash() As Byte
    Dim SecretKey() As Byte
    Dim bytes() As Byte
   
    'Test results with both strings empty:
    '128 Hex:    b936cee86c9f...etc
    '88 Base-64:  uTbO6Gyfh6pd...etc
   
    'create text and crypto objects
    Set asc = CreateObject("System.Text.UTF8Encoding")
   
    'Any of HMACSHAMD5,HMACSHA1,HMACSHA256,HMACSHA384,or HMACSHA512 can be used
    'for corresponding hashes, albeit not matching those of Managed classes.
    Set enc = CreateObject("System.Security.Cryptography.HMACSHA512")

    'make a byte array of the text to hash
    bytes = asc.Getbytes_4(sIn)
    'make a byte array of the private key
    SecretKey = asc.Getbytes_4(sSecretKey)
    'add the private key property to the encryption object
    enc.Key = SecretKey

    'make a byte array of the hash
    bytes = enc.ComputeHash_2((bytes))
   
    'convert the byte array to string
    If b64 = True Then
      StrToSHA512Salt = ConvToBase64String(bytes)
    Else
      StrToSHA512Salt = ConvToHexString(bytes)
    End If
   
    'release object variables
    Set asc = Nothing
    Set enc = Nothing

End Function

Private Function ConvToBase64String(vIn As Variant) As Variant

    Dim oD As Object
     
    Set oD = CreateObject("MSXML2.DOMDocument")
      With oD
        .LoadXML "<root />"
        .DocumentElement.DataType = "bin.base64"
        .DocumentElement.nodeTypedValue = vIn
      End With
    ConvToBase64String = Replace(oD.DocumentElement.Text, vbLf, "")
   
    Set oD = Nothing

End Function

Private Function ConvToHexString(vIn As Variant) As Variant

    Dim oD As Object
     
    Set oD = CreateObject("MSXML2.DOMDocument")
     
      With oD
        .LoadXML "<root />"
        .DocumentElement.DataType = "bin.Hex"
        .DocumentElement.nodeTypedValue = vIn
      End With
    ConvToHexString = Replace(oD.DocumentElement.Text, vbLf, "")
   
    Set oD = Nothing

End Function

Teşekkürler sayın accessman.