Visual Basic 6.0

Create XML Digital Signature using Certificate on Smart Card

See more ScMinidriver Examples

Demonstrates how to load a certificate located on a smart card or USB token and then use it for creating an XML digital signature such that the cryptographic signing happens on the smart card. Visual Basic 6.0

Dim success As Long
success = 0

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

Dim scmd As New ChilkatScMinidriver

' Reader names (smart card readers or USB tokens) can be discovered
' via List Readers or Find Smart Cards
Dim readerName As String
readerName = "SCM Microsystems Inc. SCR33x USB Smart Card Reader 0"
success = scmd.AcquireContext(readerName)
If (success = 0) Then
    Debug.Print scmd.LastErrorText
    Exit Sub
End If

' If successful, the name of the currently inserted smart card is available:
Debug.Print "Card name: " & scmd.CardName

' If desired, perform regular PIN authentication with the smartcard.
' For more details about smart card PIN authentication, see the Smart Card PIN Authentication Example
Dim retval As Long
retval = scmd.PinAuthenticate("user","000000")
If (retval <> 0) Then
    Debug.Print "PIN Authentication failed."
End If

' You can find a cerficate using any of the following certificate parts:
' "subjectDN" -- The full distinguished name of the cert.
' "subjectDN_withTags" -- Same as above, but in a format that includes the subject part tags, such as the "CN=" in "CN=something"
' "subjectCN" -- The common name part (CN) of the certificate's subject.
' "serial" -- The certificate serial number.
' "serial:issuerCN" -- The certificate serial number + the issuer's common name, delimited with a colon char.
' These are the same certificate parts that can be retrieved by listing certificates on the smart card (or USB token).
' See List Certificates on Smart Card Example
Dim certPart As String
certPart = "subjectCN"
Dim partValue As String
partValue = "PIVKey E42D60A759D39147A26E0AF2FB1183C5"

' If the certificate is found, it is loaded into the cert object.
Dim cert As New ChilkatCert
success = scmd.FindCert(certPart,partValue,cert)
If (success = 0) Then
    Debug.Print "Failed to find the certificate."
    success = scmd.DeleteContext()
    Exit Sub
End If

Debug.Print "Successfully loaded the cert object from the smart card / USB token."

' Note: When successful, the cert object is internally linked to the ScMinidriver object's authenticated session.
' The cert object can now be used to sign or do other cryptographic operations that occur on the smart card / USB token.
' If your application calls PinDeauthenticate or DeleteContext, the cert will no longer be able to sign on the smart card
' because the smart card ScMinidriver session will no longer be authenticated or deleted.

' ------------------------------------------------------------------------------------------------------------
' We have the certificate.  Now let's do the XML digital signature..

' Create the following XML to be signed:

' <?xml version="1.0" encoding="UTF-8" standalone="no" ?>
' <SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/">
'     <SOAP-ENV:Header>
'         <wsse:Security xmlns:wsse="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd" SOAP-ENV:mustUnderstand="1"></wsse:Security>
'     </SOAP-ENV:Header>
'     <SOAP-ENV:Body xmlns:SOAP-SEC="http://schemas.xmlsoap.org/soap/security/2000-12" SOAP-SEC:id="Body">
'         <z:FooBar xmlns:z="http://example.com" />
'     </SOAP-ENV:Body>
' </SOAP-ENV:Envelope>

Dim xml As New ChilkatXml
xml.Tag = "SOAP-ENV:Envelope"
success = xml.AddAttribute("xmlns:SOAP-ENV","http://schemas.xmlsoap.org/soap/envelope/")
success = xml.UpdateAttrAt("SOAP-ENV:Header|wsse:Security",1,"xmlns:wsse","http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd")
success = xml.UpdateAttrAt("SOAP-ENV:Header|wsse:Security",1,"SOAP-ENV:mustUnderstand","1")
success = xml.UpdateAttrAt("SOAP-ENV:Body",1,"xmlns:SOAP-SEC","http://schemas.xmlsoap.org/soap/security/2000-12")
success = xml.UpdateAttrAt("SOAP-ENV:Body",1,"SOAP-SEC:id","Body")
success = xml.UpdateAttrAt("SOAP-ENV:Body|z:FooBar",1,"xmlns:z","http://example.com")

' Prepare for signing...
Dim gen As New ChilkatXmlDSigGen

' Indicate where the Signature will be inserted.
gen.SigLocation = "SOAP-ENV:Envelope|SOAP-ENV:Header|wsse:Security"

' Add a reference to the fragment of the XML to be signed.

' Note: "Body" refers to the XML element having an "id" equal to "Body", where "id" is case insensitive
' and where any namespace might qualify the attribute.  In this case, the SOAP-ENV:Body fragment is signed
' NOT because the tag = "Body", but because it has SOAP-SEC:id="Body"
success = gen.AddSameDocRef("Body","sha1","EXCL_C14N","","")

' (You can read about the SignedInfoPrefixList in the online reference documentation.  It's optional..)
gen.SignedInfoPrefixList = "wsse SOAP-ENV"

' Provide the private key for signing via the certificate, and indicate that
' we want the base64 of the certificate embedded in the KeyInfo.
gen.KeyInfoType = "X509Data"
gen.X509Type = "Certificate"

' Note: Our certificate was loaded from the smartcard and is internally linked to the authenticated ScMinidriver session.
' The signing will occur on the smart card using the chosen certificate.
Dim bUsePrivateKey As Long
bUsePrivateKey = 1
success = gen.SetX509Cert(cert,bUsePrivateKey)
If (success <> 1) Then
    Debug.Print gen.LastErrorText
    Exit Sub
End If

' Everything's specified.  Now create and insert the Signature
Dim sbXml As New ChilkatStringBuilder
success = xml.GetXmlSb(sbXml)
success = gen.CreateXmlDSigSb(sbXml)
If (success <> 1) Then
    Debug.Print gen.LastErrorText
    Exit Sub
End If

' Examine the XML with the digital signature inserted
Debug.Print sbXml.GetAsString()

' ------------------------------------------------------------------------------------------------------------
' Cleanup our ScMinidriver session...

' When finished with operations that required authentication, you may if you wish, deauthenticate the session.
success = scmd.PinDeauthenticate("user")
If (success = 0) Then
    Debug.Print scmd.LastErrorText
End If

' Delete the context when finished with the card.
success = scmd.DeleteContext()
If (success = 0) Then
    Debug.Print scmd.LastErrorText
End If