(Classic ASP) RSA Sign String using Private Key of Certificate Type A3 (smart card / token)

Demonstrates RSA signing a string using the private key of a certificate type A3 (smart card, token).

Note: This is a Windows-only example.

Chilkat ActiveX Downloads

ActiveX for 32-bit and 64-bit Windows

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<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
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<%
' First get the A3 certificate that was installed on the Windows system.
' For versions of Chilkat < 10.0.0, use CreateObject("Chilkat_9_5_0.CertStore")
set certStore = Server.CreateObject("Chilkat.CertStore")

thumbprint = "12c1dd8015f3f03f7b1fa619dc24e2493ca8b4b2"

' This is specific to Windows because it is opening the Windows Current-User certificate store.
bReadOnly = 1
success = certStore.OpenCurrentUserStore(bReadOnly)
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( certStore.LastErrorText) & "</pre>"
    Response.End
End If

' Find the certificate with the desired thumbprint
' (There are many ways to locate a certificate.  This example chooses to find by thumbprint.)
' cert is a Chilkat.Cert
Set cert = certStore.FindCertBySha1Thumbprint(thumbprint)
If (certStore.LastMethodSuccess <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( "Failed to find the certificate.") & "</pre>"
    Response.End
End If

Response.Write "<pre>" & Server.HTMLEncode( "Found: " & cert.SubjectCN) & "</pre>"

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

' Provide the cert's private key
bUsePrivateKey = 1
success = rsa.SetX509Cert(cert,bUsePrivateKey)

If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( rsa.LastErrorText) & "</pre>"
    Response.End
End If

' Return the RSA signature in base64 encoded form.
rsa.EncodingMode = "base64"

' Sign the utf-8 byte representation of the string.
rsa.Charset = "utf-8"

' You can also choose other hash algorithms, such as SHA-1.
sigBase64 = rsa.SignStringENC("text to sign","SHA-256")
If (rsa.LastMethodSuccess <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( rsa.LastErrorText) & "</pre>"
    Response.End
End If

Response.Write "<pre>" & Server.HTMLEncode( "Base64 signature: " & sigBase64) & "</pre>"

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