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Zig

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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Zig
const std = @import("std");
const chilkat = @import("chilkat");

pub fn main(init: std.process.Init) !void {
    const alloc = init.arena.allocator();

    // 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>
    //

    const gen = try chilkat.XmlDSigGen.init();
    defer gen.deinit();

    gen.setSigLocation("");
    gen.setSigLocationMod(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.setSigId("xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4");
    gen.setSigNamespacePrefix("ds");
    gen.setSigNamespaceUri("http://www.w3.org/2000/09/xmldsig#");
    gen.setSigValueId("xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-sigvalue");
    gen.setSignedInfoCanonAlg("C14N");
    gen.setSignedInfoDigestMethod("sha256");

    // Create an Object to be added to the Signature.
    const object1 = try chilkat.Xml.init();
    defer object1.deinit();
    object1.setTag("xades:QualifyingProperties");
    object1.addAttribute("xmlns:xades", "http://uri.etsi.org/01903/v1.3.2#") catch {};
    object1.addAttribute("xmlns:xades141", "http://uri.etsi.org/01903/v1.4.1#") catch {};
    object1.addAttribute("Target", "#xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4") catch {};
    object1.updateAttrAt("xades:SignedProperties", true, "Id", "xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-signedprops") catch {};
    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") catch {};
    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("", try object1.getXml(alloc), "", "") catch {};

    const http = try chilkat.Http.init();
    defer http.deinit();
    const bd = try chilkat.BinData.init();
    defer bd.deinit();

    var url: [:0]const u8 = "https://isus.ezdrowie.gov.pl/fhir/Patient/123/_history/456";
    http.quickGetBd(url, bd) catch {
        std.debug.print("{s}\n", .{try http.getLastErrorText(alloc)});
        return;
    };

    // -------- Reference 1 --------
    gen.addExternalBinaryRef(url, bd, "sha256", "") catch {};
    gen.setRefIdAttr(url, "xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref0") catch {};

    // -------- Reference 2 --------
    bd.clear() catch {};
    url = "https://isus.ezdrowie.gov.pl/fhir/Encounter/789/_history/1";
    http.quickGetBd(url, bd) catch {
        std.debug.print("{s}\n", .{try http.getLastErrorText(alloc)});
        return;
    };

    gen.addExternalBinaryRef(url, bd, "sha256", "") catch {};
    gen.setRefIdAttr(url, "xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref1") catch {};

    // -------- Reference 3 --------
    bd.clear() catch {};
    url = "https://isus.ezdrowie.gov.pl/fhir/Condition/123456/_history/1";
    http.quickGetBd(url, bd) catch {
        std.debug.print("{s}\n", .{try http.getLastErrorText(alloc)});
        return;
    };

    gen.addExternalBinaryRef(url, bd, "sha256", "") catch {};
    gen.setRefIdAttr(url, "xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref2") catch {};

    // -------- Reference 4 --------
    bd.clear() catch {};
    url = "https://isus.ezdrowie.gov.pl/fhir/Procedure/123456/_history/1";
    http.quickGetBd(url, bd) catch {
        std.debug.print("{s}\n", .{try http.getLastErrorText(alloc)});
        return;
    };

    gen.addExternalBinaryRef(url, bd, "sha256", "") catch {};
    gen.setRefIdAttr(url, "xmldsig-2dde88a8-def0-43e4-8570-b031015a46b4-ref3") catch {};

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

    // Provide a certificate + private key. (PFX password is test123)
    const cert = try chilkat.Cert.init();
    defer cert.deinit();
    cert.loadPfxFile("qa_data/pfx/cert_test123.pfx", "test123") catch {
        std.debug.print("{s}\n", .{try cert.getLastErrorText(alloc)});
        return;
    };

    gen.setX509Cert(cert, true) catch {};

    gen.setKeyInfoType("X509Data");
    gen.setX509Type("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.
    const sb_xml = try chilkat.StringBuilder.init();
    defer sb_xml.deinit();

    gen.setBehaviors("IndentedSignature");

    // Sign the XML...
    gen.createXmlDSigSb(sb_xml) catch {
        std.debug.print("{s}\n", .{try gen.getLastErrorText(alloc)});
        return;
    };

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

    // Save the signed XML to a file.
    try sb_xml.writeFile("qa_output/signedXml.xml", "utf-8", false);

    std.debug.print("{s}\n", .{try sb_xml.getAsString(alloc)});

    // ----------------------------------------
    // Verify the signature we just produced...
    const verifier = try chilkat.XmlDSig.init();
    defer verifier.deinit();
    verifier.loadSignatureSb(sb_xml) catch {
        std.debug.print("{s}\n", .{try verifier.getLastErrorText(alloc)});
        return;
    };

    verifier.verifySignature(true) catch {
        std.debug.print("{s}\n", .{try verifier.getLastErrorText(alloc)});
        return;
    };

    std.debug.print("This signature was successfully verified.\n", .{});
}