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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#
bool 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;
Chilkat.XmlDSigGen gen = new Chilkat.XmlDSigGen();

gen.SigLocation = "";
gen.SigLocationMod = 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.
gen.SigId = "xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4";
gen.SigNamespacePrefix = "ds";
gen.SigNamespaceUri = "http://www.w3.org/2000/09/xmldsig#";
gen.SigValueId = "xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-sigvalue";
gen.SignedInfoCanonAlg = "C14N";
gen.SignedInfoDigestMethod = "sha256";

// Create an Object to be added to the Signature.
Chilkat.Xml object1 = new Chilkat.Xml();
object1.Tag = "xades:QualifyingProperties";
object1.AddAttribute("xmlns:xades","http://uri.etsi.org/01903/v1.3.2#");
object1.AddAttribute("xmlns:xades141","http://uri.etsi.org/01903/v1.4.1#");
object1.AddAttribute("Target","#xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4");
object1.UpdateAttrAt("xades:SignedProperties",true,"Id","xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-signedprops");
object1.UpdateChildContent("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...
object1.UpdateAttrAt("xades:SignedProperties|xades:SignedSignatureProperties|xades:SigningCertificateV2|xades:Cert|xades:CertDigest|ds:DigestMethod",true,"Algorithm","http://www.w3.org/2001/04/xmlenc#sha256");
object1.UpdateChildContent("xades:SignedProperties|xades:SignedSignatureProperties|xades:SigningCertificateV2|xades:Cert|xades:CertDigest|ds:DigestValue","TO BE GENERATED BY CHILKAT");
object1.UpdateChildContent("xades:SignedProperties|xades:SignedSignatureProperties|xades:SigningCertificateV2|xades:Cert|xades:IssuerSerialV2","TO BE GENERATED BY CHILKAT");

gen.AddObject("",object1.GetXml(),"","");

Chilkat.Http http = new Chilkat.Http();
Chilkat.BinData bd = new Chilkat.BinData();

string url = "https://isus.ezdrowie.gov.pl/fhir/Patient/123/_history/456";
success = http.QuickGetBd(url,bd);
if (success != true) {
    Debug.WriteLine(http.LastErrorText);
    return;
}

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

// -------- Reference 2 --------
bd.Clear();
url = "https://isus.ezdrowie.gov.pl/fhir/Encounter/789/_history/1";
success = http.QuickGetBd(url,bd);
if (success != true) {
    Debug.WriteLine(http.LastErrorText);
    return;
}

gen.AddExternalBinaryRef(url,bd,"sha256","");
gen.SetRefIdAttr(url,"xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref1");

// -------- Reference 3 --------
bd.Clear();
url = "https://isus.ezdrowie.gov.pl/fhir/Condition/123456/_history/1";
success = http.QuickGetBd(url,bd);
if (success != true) {
    Debug.WriteLine(http.LastErrorText);
    return;
}

gen.AddExternalBinaryRef(url,bd,"sha256","");
gen.SetRefIdAttr(url,"xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref2");

// -------- Reference 4 --------
bd.Clear();
url = "https://isus.ezdrowie.gov.pl/fhir/Procedure/123456/_history/1";
success = http.QuickGetBd(url,bd);
if (success != true) {
    Debug.WriteLine(http.LastErrorText);
    return;
}

gen.AddExternalBinaryRef(url,bd,"sha256","");
gen.SetRefIdAttr(url,"xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref3");

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

// Provide a certificate + private key. (PFX password is test123)
Chilkat.Cert cert = new Chilkat.Cert();
success = cert.LoadPfxFile("qa_data/pfx/cert_test123.pfx","test123");
if (success != true) {
    Debug.WriteLine(cert.LastErrorText);
    return;
}

gen.SetX509Cert(cert,true);

gen.KeyInfoType = "X509Data";
gen.X509Type = "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.
Chilkat.StringBuilder sbXml = new Chilkat.StringBuilder();

gen.Behaviors = "IndentedSignature";

// Sign the XML...
success = gen.CreateXmlDSigSb(sbXml);
if (success != true) {
    Debug.WriteLine(gen.LastErrorText);
    return;
}

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

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

Debug.WriteLine(sbXml.GetAsString());

// ----------------------------------------
// Verify the signature we just produced...
Chilkat.XmlDSig verifier = new Chilkat.XmlDSig();
success = verifier.LoadSignatureSb(sbXml);
if (success != true) {
    Debug.WriteLine(verifier.LastErrorText);
    return;
}

bool verified = verifier.VerifySignature(true);
if (verified != true) {
    Debug.WriteLine(verifier.LastErrorText);
    return;
}

Debug.WriteLine("This signature was successfully verified.");