(DataFlex) Create XML Digital Signature having KeyName

Demonstrates how to create an XML digital signature where the KeyInfo part will contain the KeyName element.
In this case, the public key is not specifically stored in the signed XML.
Rather, application specific information about the key is stored in the KeyName element.
The verifying application would use the KeyName to find and use the matching public key.

This example requires Chilkat v9.5.0.69 or greater.

Chilkat ActiveX Downloads

ActiveX for 32-bit and 64-bit Windows

Use ChilkatAx-win32.pkg

Procedure Test
    String sUrl
    Handle hoHttp
    Variant vSbXml
    Handle hoSbXml
    Boolean iSuccess
    Variant vDsaKey
    Handle hoDsaKey
    Handle hoXmlSigGen
    String sTemp1

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

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

    // <?xml version="1.0" encoding="UTF-8" standalone="no"?>
    // <Envelope>
    //   <Header>
    //     <Security>
    //     </Security>
    //   </Header>
    //   <Body Id="abc">
    //     <z:FooBar xmlns:z="https://www.example-code.com"/>
    //   </Body>
    // </Envelope>

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

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

    // This example uses a DSA private key for signing.  
    // There are many ways of getting an DSA private key using Chilkat.  This example
    // will load it from an encrypted PEM file.

    // In case you would like to use it, I put the DSA private key PEM file here:
    // https://www.chilkatsoft.com/exampleData/dsa1024_secret.zip
    // The password is "secret".
    Get Create (RefClass(cComChilkatPrivateKey)) To hoDsaKey
    If (Not(IsComObjectCreated(hoDsaKey))) Begin
        Send CreateComObject of hoDsaKey
    End
    Get ComLoadEncryptedPemFile Of hoDsaKey "qa_data/dsa/dsa1024_secret.pem" "secret" To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoDsaKey To sTemp1
        Showln sTemp1
        Procedure_Return
    End

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

    // Indicate where the XML Signature is to be inserted.
    Set ComSigLocation Of hoXmlSigGen To "Envelope|Header|Security"

    // Specify the fragment of the XML document to be signed.
    // This example will sign the fragment from <Body Id="abc"> ... </Body>
    Get ComAddSameDocRef Of hoXmlSigGen "abc" "sha256" "EXCL_C14N" "" "" To iSuccess

    // Provide the DSA key to be used for signing:
    Get pvComObject of hoDsaKey to vDsaKey
    Get ComSetPrivateKey Of hoXmlSigGen vDsaKey To iSuccess

    // Specify what we want to emit in the KeyInfo part of the Signature.
    // By default, it is the KeyValue that is emitted to the KeyInfo.
    // In this example,we want to emit a key name rather than the actual public key value.
    Set ComKeyInfoType Of hoXmlSigGen To "KeyName"

    // Provide a key name.  The verifying application will use the key name
    // to find/load the public key to be used for verifying the signature.
    // The key name is an arbitrary pre-agreed upon name that signer and verifier both know in advance.
    Set ComKeyInfoKeyName Of hoXmlSigGen To "dsaKey_123"

    // The KeyInfo part of the XML signature to be created will contain this:
    // 
    //     <ds:KeyInfo><ds:KeyName>dsaKey_123</ds:KeyName></ds:KeyInfo>
    // 

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

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

    Get ComWriteFile Of hoSbXml "c:/chilkatsoft.com/exampleData/signedUsingKeyName.xml" "utf-8" False To iSuccess

    // Below is the signed XML that is produced.
    // 
    // <?xml version="1.0" encoding="UTF-8" standalone="no"?>
    // <Envelope>
    //   <Header>
    //     <Security>
    //     <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#"/>
    //     <ds:SignatureMethod Algorithm="http://www.w3.org/2009/xmldsig11#dsa-sha256"/>
    //     <ds:Reference URI="#abc">
    //       <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>XTjDIHSEsDNTO9yn4cKtyXjRUjPFXkOQOLYI5mueZhk=</ds:DigestValue>
    //     </ds:Reference>
    //   </ds:SignedInfo>
    //   <ds:SignatureValue>F+HopRvLoj+9SHZxI/cGfX9SDfh+HRGZLMievGX3y/cckX1UzFuXCA==</ds:SignatureValue>
    //   <ds:KeyInfo>
    //     <ds:KeyName>dsaKey_123</ds:KeyName>
    //   </ds:KeyInfo>
    // </ds:Signature></Security>
    //   </Header>
    //   <Body Id="abc">
    //     <z:FooBar xmlns:z="https://www.example-code.com"/>
    //   </Body>
    // </Envelope>
    // 


End_Procedure