Saving hashes or encrypted passwords in MS Access

[Myrsky Varis via DotNetMonster.com]

Hi,

Can anyone tell me which field type to use in Access to save hashes or
encrypted passwords from VB.NET/ASP.NET? I have tried text and ole object,
but nothing gets saved properly. Or is my code wrong?


I am using the following function:

Public Function ComputeHashValue(ByVal data() As Byte) As Byte()
Dim hashAlg As SHA1 = SHA1.Create
Dim hashvalue() As Byte = hashAlg.ComputeHash(data)
Return hashvalue
End Function

And then the following code to save to Access:

Dim hashValue() As Byte
hashValue = ComputeHashValue(Encoding.ASCII.GetBytes
(txtPassword.Text))

dbAdaptor.Fill(ds, "main")

Dim dt As DataTable = ds.Tables(0)
Dim dr As DataRow = dt.NewRow()
Try
'Add values
dr("fldFirstName") = "FirstName"
dr("fldSurname") = "Surname"
dr("fldpassword") = hashValue

[swat]

Hi Myrsky Varis,

Use the System.Convert.ToBase64String function on the hashValue to
convert it to a Base64 encoded string before saving it to the db.

In Access: Use a text field to save the hash.

HTH

[Myrsky Varis via DotNetMonster.com]

Thanks!

Helped 100%

--
Message posted via [url]http://www.dotnetmonster.com[/url]

[Dominick Baier [DevelopMentor]]

Hello swat,

You could be even using stronger security by using something called "salted
hashes" or even "iterated salted hashes" - this makes brute force attacks
of your password database much harder and time consuming.

i have written a sample on how to store passwords using the above mentioned
technique in potential unsecure storages (==access)

you can find it here:
[url]http://www.leastprivilege.com/PermaLink.aspx?guid=b0e51388-71d1-4a6f-98d0-bc8cfbec4c3a[/url]

---------------------------------------
Dominick Baier - DevelopMentor
[url]http://www.leastprivilege.com[/url]

> Hi Myrsky Varis,
>
> Use the System.Convert.ToBase64String function on the hashValue to
> convert it to a Base64 encoded string before saving it to the db.
>
> In Access: Use a text field to save the hash.
>
> HTH
>