Here's the script you need:
<% ' IMPORTANT: save this file as UTF-8 BOM !!!
function sha256(ByVal input)
Dim hAlg,hEnc,BinaryStream,enc
set hAlg=CreateObject("System.Security.Cryptography.SHA256Managed")
set hEnc=CreateObject("System.Text.UTF8Encoding")
input=hAlg.ComputeHash_2(hEnc.GetBytes_4(input))
' --------- security check ----------
if NOT varType(input)=8209 then
Set BinaryStream=CreateObject("ADODB.Stream")
with BinaryStream
.Type=2
.CharSet="utf-8"
.Open
.WriteText input
.Position=0
.Type=1
.Position=0
input=.Read
end with
set BinaryStream=Nothing
end if
' ----------------------------------
set enc=CreateObject("MSXML2.DomDocument").CreateElement("encode")
enc.dataType="bin.hex"
enc.nodeTypedValue=input
sha256=enc.Text
set enc=nothing
set hEnc=nothing
set hAlg=nothing
end function
%>