Classic ASP

Get an S/MIME Signing Time

Demonstrates the Chilkat Mime.GetSignatureSigningTimeStr method, which returns the CMS signingTime attribute for the signer at a zero-based index, as an RFC 822-style date string in GMT. The only argument is the signer index.

Note: The file paths are relative to the application's current working directory. Absolute paths may also be used. Supply the paths appropriate to your own environment.

Background: This is the timestamp the signer asserted at signing — useful for "when was this signed" audit trails and for evaluating whether the signing certificate was valid at that moment. Because it is a signed attribute, it is tamper-evident. Guard the call with HasSignatureSigningTime, since the attribute is optional. Note it is the signer's claim, not a trusted third-party timestamp.

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Classic ASP

<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
</head>
<body>
<%
success = 0

set mime = Server.CreateObject("Chilkat.Mime")
success = mime.LoadMimeFile("qa_data/signed.eml")
If (success = 0) Then
    Response.Write "<pre>" & Server.HTMLEncode( mime.LastErrorText) & "</pre>"
    Response.End
End If

'  After verifying, get the CMS signingTime for each signer that has one, as an RFC 822 date string
'  in GMT.  The only argument is the zero-based signer index.
success = mime.Verify()
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( mime.LastErrorText) & "</pre>"
    Response.End
End If

n = mime.NumSignerCerts

For i = 0 To n - 1
    '  Only signers that included a signing time have one to retrieve.
    If (mime.HasSignatureSigningTime(i)) Then
        signingTime = mime.GetSignatureSigningTimeStr(i)
        If (mime.LastMethodSuccess = 0) Then
            Response.Write "<pre>" & Server.HTMLEncode( mime.LastErrorText) & "</pre>"
            Response.End
        End If

        Response.Write "<pre>" & Server.HTMLEncode( "Signer " & i & " signing time: " & signingTime) & "</pre>"
    End If

Next

%>
</body>
</html>