(Classic ASP) Sign a Byte Array to Create an Opaque Signature in a Byte Array

Signs data contained in a byte array to produce an opaque signature (also in a byte array). An opaque signature is a PKCS7 signature (also known as CAdES) that embeds the signed data. Also shows how to verify the signature and extract the original data.

Chilkat ActiveX Downloads

ActiveX for 32-bit and 64-bit Windows

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<%
' This example requires the Chilkat API to have been previously unlocked.
' See Global Unlock Sample for sample code.

' For versions of Chilkat < 10.0.0, use CreateObject("Chilkat_9_5_0.Cert")
set cert = Server.CreateObject("Chilkat.Cert")
success = cert.LoadPfxFile("qa_data/pfx/cert_test123.pfx","test123")
If (success = 0) Then
    Response.Write "<pre>" & Server.HTMLEncode( cert.LastErrorText) & "</pre>"
    Response.End
End If

' For versions of Chilkat < 10.0.0, use CreateObject("Chilkat_9_5_0.FileAccess")
set fac = Server.CreateObject("Chilkat.FileAccess")

fileBytes = fac.ReadEntireFile("qa_data/pdf/sample.pdf")
If (fac.LastMethodSuccess <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( fac.LastErrorText) & "</pre>"
    Response.End
End If

' For versions of Chilkat < 10.0.0, use CreateObject("Chilkat_9_5_0.Crypt2")
set crypt = Server.CreateObject("Chilkat.Crypt2")

success = crypt.SetSigningCert(cert)

' We can sign any type of file.

sigBytes = crypt.OpaqueSignBytes(fileBytes)
If (crypt.LastMethodSuccess <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( crypt.LastErrorText) & "</pre>"
    Response.End
End If

success = fac.WriteEntireFile("qa_output/sample.pdf.p7m",sigBytes)
If (fac.LastMethodSuccess <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( fac.LastErrorText) & "</pre>"
    Response.End
End If

' We can verify the opaque signature and extract the original data like this

originalData = crypt.OpaqueVerifyBytes(sigBytes)
If (crypt.LastMethodSuccess <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( crypt.LastErrorText) & "</pre>"
    Response.End
End If

success = fac.WriteEntireFile("qa_output/sample.pdf",originalData)
If (fac.LastMethodSuccess <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( fac.LastErrorText) & "</pre>"
    Response.End
End If

Response.Write "<pre>" & Server.HTMLEncode( "Signature is verified and the original data was extracted.") & "</pre>"

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