Re: XML Encryption

From: William Stacey [MVP] (staceywREMOVE_at_mvps.org)
Date: 12/08/04

  • Next message: Bruce Wood: "Re: xsd validation" 
    Date: Wed, 8 Dec 2004 10:18:58 -0500

    I think the diff is an "h" instead of "H" in your "s" var is different.
    Only one bit can change the SHA hash result a lot. 

    -- 
William Stacey, MVP
http://mvp.support.microsoft.com
"David Lownds" <david@dlownds.f2s.com> wrote in message
news:31npopF3ddc7rU1@individual.net...
> Hi William,
>
> Thank you very much for your quick response.
>
> I'm not very familiar with c# so I've tried to convert your code to vb.net
.
>
> My interpretation is
>
> Imports System
> Imports System.Collections
> Imports System.Security
> Imports System.Security.Principal
> Imports System.Security.Cryptography
> Imports System.Text
>
>
>        Dim s As String
>         s = "<Hello>there</hello>"
>         Dim sha1 As New SHA1Managed
>         Dim encoding As UnicodeEncoding = New UnicodeEncoding
>         Dim hash As Byte() = encoding.UTF8.GetBytes(s)
>         Debug.WriteLine("Hash bytes:" + hash.Length.ToString)
>         Dim base64string As String
>         base64String = Convert.ToBase64String(hash)
>         Debug.WriteLine(base64string)
>         Debug.WriteLine("Len:" + base64string.Length.ToString)
>
> To which the result I get is
>
> Hash bytes:20
> PEhlbGxvPnRoZXJlPC9oZWxsbz4=
> Len:28
>
> This is different to your result. Not being an expert at this can you
> confirm that what I've done is correct ?
>
> Many many thanks for your help on this.
>
> Dave
>
>
> "William Stacey [MVP]" <staceywREMOVE@mvps.org> wrote in message
> news:e89bJFO3EHA.3716@TK2MSFTNGP10.phx.gbl...
> >             string s = "<Hello>There</Hello>";
> >             SHA1 sha1 = SHA1.Create();
> >             byte[] hash = sha1.ComputeHash(Encoding.UTF8.GetBytes(s));
> >             Debug.WriteLine("Hash bytes:" + hash.Length);
> >             string base64String = Convert.ToBase64String(hash);
> >             Debug.WriteLine(base64String);
> >             Debug.WriteLine("Len:" + base64String.Length);
> >
> > Output
> > -------------------
> > Hash bytes:20
> > kTOBvOCt/ARaUUzkd9sqwvNacqM=
> > Len:28
> >
> > --
> > William Stacey, MVP
> > http://mvp.support.microsoft.com
> >
> > "David Lownds" <david@dlownds.f2s.com> wrote in message
> > news:31mupgF3b5u48U1@individual.net...
> > > Dear All,
> > >
> > > I need to do the following to an xml file in vb.net.
> > >
> > > - Read in the file
> > >
> > > - canonicalise (c14n) the XML document
> > > - generate a 160-bit binary secure hash from the canonicalise XML
> > >
> > > using the SHA-1 algorithm
> > >
> > > - encode the binary data using base-64 to produce a 28 character
string
> > >
> > > Can anyone provide me with some help ? I'm very stuck on this.
> > > --
> > > Cheers
> > >
> > > Dave
> > >
> > >
> >
>
>
  • Next message: Bruce Wood: "Re: xsd validation"

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