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C

XML Signature Multiple External References

See more XML Digital Signatures Examples

Demonstrates how to add multiple external references to an XML digital signature.

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C
#include <C_CkXmlDSigGen.h>
#include <C_CkXml.h>
#include <C_CkHttp.h>
#include <C_CkBinData.h>
#include <C_CkCert.h>
#include <C_CkStringBuilder.h>
#include <C_CkXmlDSig.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkXmlDSigGen gen;
    HCkXml object1;
    HCkHttp http;
    HCkBinData bd;
    const char *url;
    HCkCert cert;
    HCkStringBuilder sbXml;
    HCkXmlDSig verifier;
    BOOL verified;

    success = FALSE;

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

    // This example creates the following signed XML with multiple external references:

    // <?xml version="1.0" encoding="UTF-8"?>
    // <ds:Signature xmlns:ds="http://www.w3.org/2000/09/xmldsig#" Id="xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4">
    //     <ds:SignedInfo>
    //         <ds:CanonicalizationMethod Algorithm="http://www.w3.org/TR/2001/REC-xml-c14n-20010315"/>
    //         <ds:SignatureMethod Algorithm="http://www.w3.org/2001/04/xmldsig-more#rsa-sha256"/>
    //         <ds:Reference Id="xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref0" URI="https://isus.ezdrowie.gov.pl/fhir/Patient/123/_history/456">
    //             <ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/>
    //             <ds:DigestValue>...</ds:DigestValue>
    //         </ds:Reference>
    //         <ds:Reference Id="xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref1" URI="https://isus.ezdrowie.gov.pl/fhir/Encounter/124/_history/22">
    //             <ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/>
    //             <ds:DigestValue>...</ds:DigestValue>
    //         </ds:Reference>
    //         <ds:Reference Id="xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref2" URI="https://isus.ezdrowie.gov.pl/fhir/Condition/125/_history/1">
    //             <ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/>
    //             <ds:DigestValue>...</ds:DigestValue>
    //         </ds:Reference>
    //         <ds:Reference Id="xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref3" URI="https://isus.ezdrowie.gov.pl/fhir/Procedure/126/_history/1">
    //             <ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/>
    //             <ds:DigestValue>...</ds:DigestValue>
    //         </ds:Reference>
    //         <ds:Reference Type="http://uri.etsi.org/01903#SignedProperties" URI="#xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-signedprops">
    //             <ds:Transforms>
    //                 <ds:Transform Algorithm="http://www.w3.org/TR/2001/REC-xml-c14n-20010315"/>
    //             </ds:Transforms>
    //             <ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/>
    //             <ds:DigestValue>...</ds:DigestValue>
    //         </ds:Reference>
    //     </ds:SignedInfo>
    //     <ds:SignatureValue Id="xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-sigvalue">...</ds:SignatureValue>
    //     <ds:KeyInfo>
    //         <ds:X509Data>
    //             <ds:X509Certificate>...</ds:X509Certificate>
    //             <ds:X509SubjectName>...</ds:X509SubjectName>
    //             <ds:X509IssuerSerial>
    //                 <ds:X509IssuerName>...</ds:X509IssuerName>
    //                 <ds:X509SerialNumber>...</ds:X509SerialNumber>
    //             </ds:X509IssuerSerial>
    //         </ds:X509Data>
    //     </ds:KeyInfo>
    //     <ds:Object>
    //         <xades:QualifyingProperties xmlns:xades="http://uri.etsi.org/01903/v1.3.2#" xmlns:xades141="http://uri.etsi.org/01903/v1.4.1#" Target="#xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4">
    //             <xades:SignedProperties Id="xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-signedprops">
    //                 <xades:SignedSignatureProperties>
    //                     <xades:SigningTime>2021-06-02T07:10:13.306+02:00</xades:SigningTime>
    //                     <xades:SigningCertificate>
    //                         <xades:Cert>
    //                             <xades:CertDigest>
    //                                 <ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/>
    //                                 <ds:DigestValue>...</ds:DigestValue>
    //                             </xades:CertDigest>
    //                             <xades:IssuerSerial>
    //                                 <ds:X509IssuerName>...</ds:X509IssuerName>
    //                                 <ds:X509SerialNumber>...</ds:X509SerialNumber>
    //                             </xades:IssuerSerial>
    //                         </xades:Cert>
    //                         <xades:Cert>
    //                             <xades:CertDigest>
    //                                 <ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/>
    //                                 <ds:DigestValue>...</ds:DigestValue>
    //                             </xades:CertDigest>
    //                             <xades:IssuerSerial>
    //                                 <ds:X509IssuerName>...</ds:X509IssuerName>
    //                                 <ds:X509SerialNumber>...</ds:X509SerialNumber>
    //                             </xades:IssuerSerial>
    //                         </xades:Cert>
    //                         <xades:Cert>
    //                             <xades:CertDigest>
    //                                 <ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/>
    //                                 <ds:DigestValue>...</ds:DigestValue>
    //                             </xades:CertDigest>
    //                             <xades:IssuerSerial>
    //                                 <ds:X509IssuerName>...</ds:X509IssuerName>
    //                                 <ds:X509SerialNumber>...</ds:X509SerialNumber>
    //                             </xades:IssuerSerial>
    //                         </xades:Cert>
    //                     </xades:SigningCertificate>
    //                 </xades:SignedSignatureProperties>
    //             </xades:SignedProperties>
    //         </xades:QualifyingProperties>
    //     </ds:Object>
    // </ds:Signature>
    // 

    success = TRUE;
    gen = CkXmlDSigGen_Create();

    CkXmlDSigGen_putSigLocation(gen,"");
    CkXmlDSigGen_putSigLocationMod(gen,0);
    // Note: ID's simply need to be unique values in the signed XML document.  They don't necessarily need to be GUID/UUID formatted.
    CkXmlDSigGen_putSigId(gen,"xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4");
    CkXmlDSigGen_putSigNamespacePrefix(gen,"ds");
    CkXmlDSigGen_putSigNamespaceUri(gen,"http://www.w3.org/2000/09/xmldsig#");
    CkXmlDSigGen_putSigValueId(gen,"xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-sigvalue");
    CkXmlDSigGen_putSignedInfoCanonAlg(gen,"C14N");
    CkXmlDSigGen_putSignedInfoDigestMethod(gen,"sha256");

    // Create an Object to be added to the Signature.
    object1 = CkXml_Create();
    CkXml_putTag(object1,"xades:QualifyingProperties");
    CkXml_AddAttribute(object1,"xmlns:xades","http://uri.etsi.org/01903/v1.3.2#");
    CkXml_AddAttribute(object1,"xmlns:xades141","http://uri.etsi.org/01903/v1.4.1#");
    CkXml_AddAttribute(object1,"Target","#xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4");
    CkXml_UpdateAttrAt(object1,"xades:SignedProperties",TRUE,"Id","xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-signedprops");
    CkXml_UpdateChildContent(object1,"xades:SignedProperties|xades:SignedSignatureProperties|xades:SigningTime","TO BE GENERATED BY CHILKAT");
    // This assumes there are 3 certs in the certificate chain:  The signing certificate, an intermediate root, and the root CA.
    // Remove the lines with "Cert[2]" if there is no intermediate root...
    CkXml_UpdateAttrAt(object1,"xades:SignedProperties|xades:SignedSignatureProperties|xades:SigningCertificateV2|xades:Cert|xades:CertDigest|ds:DigestMethod",TRUE,"Algorithm","http://www.w3.org/2001/04/xmlenc#sha256");
    CkXml_UpdateChildContent(object1,"xades:SignedProperties|xades:SignedSignatureProperties|xades:SigningCertificateV2|xades:Cert|xades:CertDigest|ds:DigestValue","TO BE GENERATED BY CHILKAT");
    CkXml_UpdateChildContent(object1,"xades:SignedProperties|xades:SignedSignatureProperties|xades:SigningCertificateV2|xades:Cert|xades:IssuerSerialV2","TO BE GENERATED BY CHILKAT");

    CkXmlDSigGen_AddObject(gen,"",CkXml_getXml(object1),"","");

    http = CkHttp_Create();
    bd = CkBinData_Create();

    url = "https://isus.ezdrowie.gov.pl/fhir/Patient/123/_history/456";
    success = CkHttp_QuickGetBd(http,url,bd);
    if (success != TRUE) {
        printf("%s\n",CkHttp_lastErrorText(http));
        CkXmlDSigGen_Dispose(gen);
        CkXml_Dispose(object1);
        CkHttp_Dispose(http);
        CkBinData_Dispose(bd);
        return;
    }

    // -------- Reference 1 --------
    CkXmlDSigGen_AddExternalBinaryRef(gen,url,bd,"sha256","");
    CkXmlDSigGen_SetRefIdAttr(gen,url,"xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref0");

    // -------- Reference 2 --------
    CkBinData_Clear(bd);
    url = "https://isus.ezdrowie.gov.pl/fhir/Encounter/789/_history/1";
    success = CkHttp_QuickGetBd(http,url,bd);
    if (success != TRUE) {
        printf("%s\n",CkHttp_lastErrorText(http));
        CkXmlDSigGen_Dispose(gen);
        CkXml_Dispose(object1);
        CkHttp_Dispose(http);
        CkBinData_Dispose(bd);
        return;
    }

    CkXmlDSigGen_AddExternalBinaryRef(gen,url,bd,"sha256","");
    CkXmlDSigGen_SetRefIdAttr(gen,url,"xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref1");

    // -------- Reference 3 --------
    CkBinData_Clear(bd);
    url = "https://isus.ezdrowie.gov.pl/fhir/Condition/123456/_history/1";
    success = CkHttp_QuickGetBd(http,url,bd);
    if (success != TRUE) {
        printf("%s\n",CkHttp_lastErrorText(http));
        CkXmlDSigGen_Dispose(gen);
        CkXml_Dispose(object1);
        CkHttp_Dispose(http);
        CkBinData_Dispose(bd);
        return;
    }

    CkXmlDSigGen_AddExternalBinaryRef(gen,url,bd,"sha256","");
    CkXmlDSigGen_SetRefIdAttr(gen,url,"xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref2");

    // -------- Reference 4 --------
    CkBinData_Clear(bd);
    url = "https://isus.ezdrowie.gov.pl/fhir/Procedure/123456/_history/1";
    success = CkHttp_QuickGetBd(http,url,bd);
    if (success != TRUE) {
        printf("%s\n",CkHttp_lastErrorText(http));
        CkXmlDSigGen_Dispose(gen);
        CkXml_Dispose(object1);
        CkHttp_Dispose(http);
        CkBinData_Dispose(bd);
        return;
    }

    CkXmlDSigGen_AddExternalBinaryRef(gen,url,bd,"sha256","");
    CkXmlDSigGen_SetRefIdAttr(gen,url,"xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref3");

    // -------- Reference 5 --------
    CkXmlDSigGen_AddObjectRef(gen,"xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-signedprops","sha256","C14N","","http://uri.etsi.org/01903#SignedProperties");

    // Provide a certificate + private key. (PFX password is test123)
    cert = CkCert_Create();
    success = CkCert_LoadPfxFile(cert,"qa_data/pfx/cert_test123.pfx","test123");
    if (success != TRUE) {
        printf("%s\n",CkCert_lastErrorText(cert));
        CkXmlDSigGen_Dispose(gen);
        CkXml_Dispose(object1);
        CkHttp_Dispose(http);
        CkBinData_Dispose(bd);
        CkCert_Dispose(cert);
        return;
    }

    CkXmlDSigGen_SetX509Cert(gen,cert,TRUE);

    CkXmlDSigGen_putKeyInfoType(gen,"X509Data");
    CkXmlDSigGen_putX509Type(gen,"IssuerSerial,SubjectName,Certificate");

    // This will be an enveloping signature where the Signature element
    // is the XML document root, the signed data is contained within Object
    // tag(s) within the Signature.
    // Therefore, pass an empty sbXml to CreateXmlDsigSb.
    sbXml = CkStringBuilder_Create();

    CkXmlDSigGen_putBehaviors(gen,"IndentedSignature");

    // Sign the XML...
    success = CkXmlDSigGen_CreateXmlDSigSb(gen,sbXml);
    if (success != TRUE) {
        printf("%s\n",CkXmlDSigGen_lastErrorText(gen));
        CkXmlDSigGen_Dispose(gen);
        CkXml_Dispose(object1);
        CkHttp_Dispose(http);
        CkBinData_Dispose(bd);
        CkCert_Dispose(cert);
        CkStringBuilder_Dispose(sbXml);
        return;
    }

    // -----------------------------------------------

    // Save the signed XML to a file.
    success = CkStringBuilder_WriteFile(sbXml,"qa_output/signedXml.xml","utf-8",FALSE);

    printf("%s\n",CkStringBuilder_getAsString(sbXml));

    // ----------------------------------------
    // Verify the signature we just produced...
    verifier = CkXmlDSig_Create();
    success = CkXmlDSig_LoadSignatureSb(verifier,sbXml);
    if (success != TRUE) {
        printf("%s\n",CkXmlDSig_lastErrorText(verifier));
        CkXmlDSigGen_Dispose(gen);
        CkXml_Dispose(object1);
        CkHttp_Dispose(http);
        CkBinData_Dispose(bd);
        CkCert_Dispose(cert);
        CkStringBuilder_Dispose(sbXml);
        CkXmlDSig_Dispose(verifier);
        return;
    }

    verified = CkXmlDSig_VerifySignature(verifier,TRUE);
    if (verified != TRUE) {
        printf("%s\n",CkXmlDSig_lastErrorText(verifier));
        CkXmlDSigGen_Dispose(gen);
        CkXml_Dispose(object1);
        CkHttp_Dispose(http);
        CkBinData_Dispose(bd);
        CkCert_Dispose(cert);
        CkStringBuilder_Dispose(sbXml);
        CkXmlDSig_Dispose(verifier);
        return;
    }

    printf("This signature was successfully verified.\n");


    CkXmlDSigGen_Dispose(gen);
    CkXml_Dispose(object1);
    CkHttp_Dispose(http);
    CkBinData_Dispose(bd);
    CkCert_Dispose(cert);
    CkStringBuilder_Dispose(sbXml);
    CkXmlDSig_Dispose(verifier);

    }