(DataFlex) Create XML Signature with Certificate's Private Key

Demonstrates how to create an XML digital signature using a certificate's RSA private key. This example loads the certificate from a PFX, and uses the cert's associated private key to sign. The public key is embedded in the XML signature as a ds:KeyInfo / ds:KeyValue / dsRSAKeyValue element.

This example requires Chilkat v9.5.0.71 or greater.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

Use ChilkatAx-win32.pkg

Procedure Test
    String sUrl
    Handle hoHttp
    Variant vSbSoapXml
    Handle hoSbSoapXml
    Boolean iSuccess
    Handle hoCert
    Variant vRsaKey
    Handle hoRsaKey
    Handle hoXmlSigGen
    String sTemp1
    Boolean bTemp1

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

    // The SOAP XML to be signed in this example contains the following:

    // <?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>
    // 

    // The above XML is available at https://www.chilkatsoft.com/exampleData/soapToSign.xml
    // Fetch the XML and then sign it..

    Move "https://www.chilkatsoft.com/exampleData/soapToSign.xml" To sUrl
    Get Create (RefClass(cComChilkatHttp)) To hoHttp
    If (Not(IsComObjectCreated(hoHttp))) Begin
        Send CreateComObject of hoHttp
    End
    Get Create (RefClass(cComChilkatStringBuilder)) To hoSbSoapXml
    If (Not(IsComObjectCreated(hoSbSoapXml))) Begin
        Send CreateComObject of hoSbSoapXml
    End
    Get pvComObject of hoSbSoapXml to vSbSoapXml
    Get ComQuickGetSb Of hoHttp sUrl vSbSoapXml To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoHttp To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Load a PFX file containing the certificate + private key.
    Get Create (RefClass(cComChilkatCert)) To hoCert
    If (Not(IsComObjectCreated(hoCert))) Begin
        Send CreateComObject of hoCert
    End
    Get ComLoadPfxFile Of hoCert "/somedir/myPfx.pfx" "pfx_password" To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoCert To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Get the RSA private key for signing...
    Get ComExportPrivateKey Of hoCert To vRsaKey
    If (IsComObject(vRsaKey)) Begin
        Get Create (RefClass(cComChilkatPrivateKey)) To hoRsaKey
        Set pvComObject Of hoRsaKey To vRsaKey
    End
    Get ComLastMethodSuccess Of hoCert To bTemp1
    If (bTemp1 <> True) Begin
        Get ComLastErrorText Of hoCert To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // To create the XML digital signature (i.e. embed the signature within
    // the SOAP XML), we specify what is desired, and then call the method to 
    // create the XML signature.
    // 
    // For example, the application must provide the following:
    //     - Where to put the signature.
    //     - What to sign.
    //     - The algorithms to be used.
    //     - The key to be used for signing.
    // 

    Get Create (RefClass(cComChilkatXmlDSigGen)) To hoXmlSigGen
    If (Not(IsComObjectCreated(hoXmlSigGen))) Begin
        Send CreateComObject of hoXmlSigGen
    End

    // In this example, we're going to put the signature within the wsse:Security element.
    // To specify the location, set the SigLocation property to the XML path to this element,
    // using vertical bar characters to separate tags.
    Set ComSigLocation Of hoXmlSigGen To "SOAP-ENV:Envelope|SOAP-ENV:Header|wsse:Security"

    // An XML digital signature contains one or more references.  These are references to the parts
    // of the XML document to be signed (a same document reference), or can be external references.
    // This example will add a single same-document reference.  We'll add a reference to the XML fragment
    // at SOAP-ENV:Body, which is indicated by providing the value of the "ID" attribute (where "ID" is case
    // insensitive).  For each same-document reference, we must also indicate the hash algorithm and XML canonicalization
    // algorithm to be used.  For this example we'll choose SHA-256 and Exclusive XML Canonicalization.
    Get ComAddSameDocRef Of hoXmlSigGen "Body" "sha256" "EXCL_C14N" "" "" To iSuccess

    // Let's provide the RSA key to be used for signing:
    Get ComSetPrivateKey Of hoXmlSigGen vRsaKey To iSuccess
    Send Destroy of hoRsaKey

    // We're leaving the following properties at their default values:
    // 
    //    - SigNamespacePrefix (default is "ds")
    //    - SigningAlg (for RSA keys. The default is PKCS1-v1_5, can be changed to RSASSA-PSS.)
    //    - SignedInfoCanonAlg  (default is EXCL_C14N)
    //    - SignedInfoDigestMethod (default is sha256)
    //    - KeyInfoType (default is "KeyValue", where the RSA public key is included in the Signature)

    // Note: Each Reference has it's own specified algorithms for XML canonicalization and hashing,
    // and the actual signature part (the SignedInfo) has it's own algorithms for the same.
    // They may or may not be the same.  In this example, we use Exclusive XML Canonicalization and SHA-256 throughout.

    // Finally, we're going to set one property that's optional, but commonly used.
    // It's the SignedInfoPrefixList.  In this case, we're using Exclusive Canonicalization, and the signature
    // will be placed in a location within the XML document where namespace prefixes are used in the ancestors.
    // Specifically, the "wsse" and "SOAP-ENV" namespace prefixes are used.
    Set ComSignedInfoPrefixList Of hoXmlSigGen To "wsse SOAP-ENV"

    // OK, everything's specified, so let's create the XML digital signature:
    // This in-place signs the XML.  If successful, sbSoapXml will contain the 
    // XML with the digital signature at the specified location.
    Get pvComObject of hoSbSoapXml to vSbSoapXml
    Get ComCreateXmlDSigSb Of hoXmlSigGen vSbSoapXml To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoXmlSigGen To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Examine the signed SOAP XML:
    Get ComGetAsString Of hoSbSoapXml To sTemp1
    Showln sTemp1

    // This is the signed SOAP XML.
    // Chilkat emits the Signature in compact form on a single line.  Whitespace in XML signatures
    // matters.  Chilkat's opinion is that writing the Signature without whitespace minimizes the chance
    // for problems with whatever software might be verifying the signature.

    // <?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"><ds:Signature xmlns:ds="http://www.w3.org/2000/09/xmldsig#"><ds:SignedInfo><ds:CanonicalizationMethod Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#"><InclusiveNamespaces xmlns="http://www.w3.org/2001/10/xml-exc-c14n#" PrefixList="wsse SOAP-ENV"/></ds:CanonicalizationMethod><ds:SignatureMethod Algorithm="http://www.w3.org/2001/04/xmldsig-more#rsa-sha256"/><ds:Reference URI="#Body"><ds:Transforms><ds:Transform Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#"/></ds:Transforms><ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/><ds:DigestValue>OwgHPZNfDkXnZsjpfzXqAcT3RV3HzmTsEy2bP44FJ0M=</ds:DigestValue></ds:Reference></ds:SignedInfo><ds:SignatureValue>C+7FWngUpJ33Q1yq8uuscjCyPN2IO4cJhpMv03Jrrht1V+4gvJQLIBk6HHjo1uPQyfYj6zji3pg+fOyGUptp17CsRvjCzSpP35vB2lEzHeS8dcY8XfrEtTP/0FNn75LmhhkOPy0wjWkgDVbgzhXpEk9az8r8fQVTM3vrcmXT+WdMWJXKBRFt6PLAhsFt0scOFTWAkLGyCwygzimDKX2nT63TOit9BigtIx7fPRuMkbybMKCGGABq2DiEbvrPOiN3SUYpyMNR9KehRAGN+OWnESaDC6DhOvbKR88XHkM+GeaRe9PWdrRHrwGfp3qgolKjR/wFRSa1YGSBKAhDJFBcdg==</ds:SignatureValue><ds:KeyInfo><ds:KeyValue><ds:RSAKeyValue><ds:Modulus>sXeRhM55P13FbpNcXAMR3olbw2Wa6keZIHu5YTZYUBTlYWId+pNiwUz3zFIEo+0IfYR0H27ybIycQO+1IIzJofUFNMAL3tZps2OKPlsjuCPls6kXpXhv/gvhux8LrCtp4PcKWqJ6QVOZKChc7WAx40qFWzHi57ueqRTv3x0kESqGg/VjsqyTEvb55psJO2RsfhLT7+YVh3hImRM3RDaJdkTkPuOxeFyT6N7VXD09329sLuS3QkUbE9zEKDnz9X3d8dEQdJhSI9ba5fxl8R7fu8pB67ElfzFml96X1jLFtzy1pzOT5Fc4ROcaqlYckVzdBq9sxezm6MYmDBjNAcibRw==</ds:Modulus><ds:Exponent>AQAB</ds:Exponent></ds:RSAKeyValue></ds:KeyValue></ds:KeyInfo></ds:Signature></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>

    // Here's the signature part formatted for easier reading.
    // (Adding whitespace to the SignedInfo breaks the signature, so you wouldn't want to do this..)

    //     <ds:Signature xmlns:ds="http://www.w3.org/2000/09/xmldsig#">
    //         <ds:SignedInfo>
    //             <ds:CanonicalizationMethod Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#">
    //                 <InclusiveNamespaces xmlns="http://www.w3.org/2001/10/xml-exc-c14n#" PrefixList="wsse SOAP-ENV" />
    //             </ds:CanonicalizationMethod>
    //             <ds:SignatureMethod Algorithm="http://www.w3.org/2001/04/xmldsig-more#rsa-sha256" />
    //             <ds:Reference URI="#Body">
    //                 <ds:Transforms>
    //                     <ds:Transform Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#" />
    //                 </ds:Transforms>
    //                 <ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256" />
    //                 <ds:DigestValue>OwgHPZNfDkXnZsjpfzXqAcT3RV3HzmTsEy2bP44FJ0M=</ds:DigestValue>
    //             </ds:Reference>
    //         </ds:SignedInfo>
    //         <ds:SignatureValue>C+7FWngUp....BKAhDJFBcdg==</ds:SignatureValue>
    //         <ds:KeyInfo>
    //             <ds:KeyValue>
    //                 <ds:RSAKeyValue>
    //                     <ds:Modulus>sXeRhM55P13FbpNcXAMR....MYmDBjNAcibRw==</ds:Modulus>
    //                     <ds:Exponent>AQAB</ds:Exponent>
    //                 </ds:RSAKeyValue>
    //             </ds:KeyValue>
    //         </ds:KeyInfo>
    //     </ds:Signature>


End_Procedure