PKCS7 SignedData Signature (embeds Signed Data)

How to create a PKCS7 signature. The resulting PKCS7 structure is encoded to a printable string using hex or base64 encoding. The data being signed is embedded within the PKCS#7 structure.

Demonstrates how to verify the signature and recover the original data.

Chilkat ActiveX Downloads

ActiveX for 32-bit and 64-bit Windows

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<%
set crypt = Server.CreateObject("Chilkat_9_5_0.Crypt2")

'  Any string argument automatically begins the 30-day trial.
success = crypt.UnlockComponent("30-day trial")
If (success <> 1) Then
    Response.Write "Crypt component unlock failed" & "<br>"

End If

set cert = Server.CreateObject("Chilkat_9_5_0.Cert")
success = cert.LoadByCommonName("Chilkat Software")
If (success <> 1) Then
    Response.Write cert.LastErrorText & "<br>"

End If

'  Make sure this certificate has a private key available:

bHasPrivateKey = cert.HasPrivateKey()
If (bHasPrivateKey <> 1) Then
    Response.Write "No private key available for signing." & "<br>"

End If

'  Tell the encryption component to use this cert.
crypt.SetSigningCert cert

strData = "This is the data to be signed."

'  Indicate that the PKCS7 signature should be returned
'  as a base64 encoded string:
crypt.EncodingMode = "base64"

'  The EncodingMode may be set to other values such as
'  "hex", "url", "quoted-printable", etc.

strSignatureWithData = crypt.OpaqueSignStringENC(strData)

Response.Write Server.HTMLEncode( strSignatureWithData) & "<br>"

'  Now verify the signature against the original data.

'  Tell the component what certificate to use for verification.
crypt.SetVerifyCert cert

originalData = crypt.OpaqueVerifyStringENC(strSignatureWithData)
If (originalData = vbNullString ) Then
    '  The signature verification failed.
    Response.Write crypt.LastErrorText & "<br>"
Else
    Response.Write Server.HTMLEncode( originalData) & "<br>"
    Response.Write "Signature verified!" & "<br>"
End If

%>
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