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Lua Requires Chilkat v11.0.0+

Signed Zip as Base64 with XAdES-BES

See more XAdES Examples

This example is to help companies implement a solution for sending XAdES-BES to the Polish government for reporting purposes. Specifically:

Przed podpisaniem deklaracja zbiorcza (PIT-11Z, PIT-8CZ, PIT-40Z, PIT-RZ) musi zostać
umieszczona w archiwum ZIP. W tym przypadku, podpisywany jest plik archiwum ZIP,
przyjmujący w podpisie XAdES-BES formę zakodowaną base64.

The example demonstrates the following:

  1. Zip an XML file (PIT-11Z.xml is zipped to PIT-11Z.zip)
  2. Create XML to be signed, where the XML contains the base64 encoded content of the PIT-11Z.zip archive.
  3. XAdES-BES sign the XML containing the base64 zip.

This example will also show the reverse:

  1. Verify the signed XML.
  2. Extract the PIT-11z.zip from the signed XML.
  3. Unzip the PIT-11Z.zip to get the original PIT-11Z.xml

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    -- In the following call to loadlib, change the path (./chilkat.dll) to the relative or absolute directory where the chilkat.dll, chilkat.so, or chilkat.dylib is located.
    chilkat = assert(package.loadlib("./chilkat.dll", "luaopen_chilkat"))()
    print(chilkat._VERSION)

    local success = false

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

    --  Zip the PIT-11Z.xml to create PIT-11Z.zip (not as a .zip file, but in-memory).
    local sbXmlToZip = chilkat.newStringBuilder{}
    success = sbXmlToZip:LoadFile("qa_data/xml/PIT-11Z.xml","utf-8")
    if success ~= true then
        print("Failed to load the XML to be zipped.")

    end

    local zip = chilkat.newZip{}

    --  Initialize the zip object. No file is created in this call.
    --  It should always return true.
    success = zip:NewZip("PIT-11Z.zip")

    --  Add the XML to be zipped.
    zip:AddSb("PIT-11Z.xml",sbXmlToZip,"utf-8")

    --  Write the zip to a BinData object.
    local bdZip = chilkat.newBinData{}
    zip:WriteBd(bdZip)
    --  The contents of the bdZip will be retrieved in base64 format when needed below..

    local gen = chilkat.newXmlDSigGen{}

    gen:setSigLocation("")
    gen:setSigLocationMod(0)

    gen:setSigId("Signature_2a8df7f8-b958-40cc-83f6-edb53b837347_19")
    gen:setSigNamespacePrefix("ds")
    gen:setSigNamespaceUri("http://www.w3.org/2000/09/xmldsig#")
    gen:setSigValueId("SignatureValue_2a8df7f8-b958-40cc-83f6-edb53b837347_52")
    gen:setSignedInfoId("SignedInfo_2a8df7f8-b958-40cc-83f6-edb53b837347_41")
    gen:setSignedInfoCanonAlg("C14N")
    gen:setSignedInfoDigestMethod("sha1")

    --  Set the KeyInfoId before adding references..
    gen:setKeyInfoId("KeyInfo_2a8df7f8-b958-40cc-83f6-edb53b837347_24")

    --  Create an Object to be added to the Signature.
    local object1 = chilkat.newXml{}
    object1:setTag("xades:QualifyingProperties")
    object1:AddAttribute("xmlns:xades","http://uri.etsi.org/01903/v1.3.2#")
    object1:AddAttribute("Id","QualifyingProperties_2a8df7f8-b958-40cc-83f6-edb53b837347_43")
    object1:AddAttribute("Target","#Signature_2a8df7f8-b958-40cc-83f6-edb53b837347_19")
    object1:UpdateAttrAt("xades:SignedProperties",true,"Id","SignedProperties_2a8df7f8-b958-40cc-83f6-edb53b837347_4e")
    object1:UpdateAttrAt("xades:SignedProperties|xades:SignedSignatureProperties",true,"Id","SignedSignatureProperties_2a8df7f8-b958-40cc-83f6-edb53b837347_0a")
    --  Chilkat will replace the strings "TO BE GENERATED BY CHILKAT" with actual values when the signature is created.
    object1:UpdateChildContent("xades:SignedProperties|xades:SignedSignatureProperties|xades:SigningTime","TO BE GENERATED BY CHILKAT")
    --  Note: It may be that http://www.w3.org/2001/04/xmlenc#sha256 is needed in the following line instead of http://www.w3.org/2000/09/xmldsig#sha1
    object1:UpdateAttrAt("xades:SignedProperties|xades:SignedSignatureProperties|xades:SigningCertificateV2|xades:Cert|xades:CertDigest|ds:DigestMethod",true,"Algorithm","http://www.w3.org/2000/09/xmldsig#sha1")
    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")
    object1:UpdateAttrAt("xades:SignedProperties|xades:SignedDataObjectProperties",true,"Id","SignedDataObjectProperties_2a8df7f8-b958-40cc-83f6-edb53b837347_4b")
    object1:UpdateAttrAt("xades:SignedProperties|xades:SignedDataObjectProperties|xades:DataObjectFormat",true,"ObjectReference","#Reference1_2a8df7f8-b958-40cc-83f6-edb53b837347_27")
    object1:UpdateChildContent("xades:SignedProperties|xades:SignedDataObjectProperties|xades:DataObjectFormat|xades:Description","MIME-Version: 1.0\r\nContent-Type: application/zip\r\nContent-Transfer-Encoding: binary\r\nContent-Disposition: filename="PIT-11Z.zip"")
    object1:UpdateAttrAt("xades:SignedProperties|xades:SignedDataObjectProperties|xades:DataObjectFormat|xades:ObjectIdentifier|xades:Identifier",true,"Qualifier","OIDAsURI")
    object1:UpdateChildContent("xades:SignedProperties|xades:SignedDataObjectProperties|xades:DataObjectFormat|xades:ObjectIdentifier|xades:Identifier","http://www.certum.pl/OIDAsURI/signedFile/1.2.616.1.113527.3.1.1.3.1")
    object1:UpdateChildContent("xades:SignedProperties|xades:SignedDataObjectProperties|xades:DataObjectFormat|xades:ObjectIdentifier|xades:Description","Opis formatu dokumentu oraz jego pelna nazwa")
    object1:UpdateChildContent("xades:SignedProperties|xades:SignedDataObjectProperties|xades:DataObjectFormat|xades:ObjectIdentifier|xades:DocumentationReferences|xades:DocumentationReference","http://www.certum.pl/OIDAsURI/signedFile.pdf")
    object1:UpdateChildContent("xades:SignedProperties|xades:SignedDataObjectProperties|xades:DataObjectFormat|xades:MimeType","application/zip")
    object1:UpdateChildContent("xades:SignedProperties|xades:SignedDataObjectProperties|xades:CommitmentTypeIndication|xades:CommitmentTypeId|xades:Identifier","http://uri.etsi.org/01903/v1.2.2#ProofOfApproval")
    object1:UpdateChildContent("xades:SignedProperties|xades:SignedDataObjectProperties|xades:CommitmentTypeIndication|xades:AllSignedDataObjects","")
    object1:UpdateAttrAt("xades:UnsignedProperties",true,"Id","UnsignedProperties_2a8df7f8-b958-40cc-83f6-edb53b837347_55")

    --  Emit XML in compact (single-line) format to avoid whitespace problems.
    object1:setEmitCompact(true)
    gen:AddObject("",object1:GetXml(),"","")

    --  Create an Object to be added to the Signature.
    --  This is where we add the base64 representation of the PIT-11Z.zip
    gen:AddObject("Object1_2a8df7f8-b958-40cc-83f6-edb53b837347",bdZip:GetEncoded("base64"),"","http://www.w3.org/2000/09/xmldsig#base64")

    --  -------- Reference 1 --------
    gen:AddObjectRef("Object1_2a8df7f8-b958-40cc-83f6-edb53b837347","sha1","C14N_WithComments","","")
    gen:SetRefIdAttr("Object1_2a8df7f8-b958-40cc-83f6-edb53b837347","Reference1_2a8df7f8-b958-40cc-83f6-edb53b837347_27")

    --  -------- Reference 2 --------
    gen:AddObjectRef("SignedProperties_2a8df7f8-b958-40cc-83f6-edb53b837347_4e","sha1","","","http://uri.etsi.org/01903#SignedProperties")
    gen:SetRefIdAttr("SignedProperties_2a8df7f8-b958-40cc-83f6-edb53b837347_4e","SignedProperties-Reference_2a8df7f8-b958-40cc-83f6-edb53b837347_28")

    --  Provide a certificate + private key. (PFX password is test123)
    local cert = chilkat.newCert{}
    success = cert:LoadPfxFile("qa_data/pfx/cert_test123.pfx","test123")
    if success == false then
        print(cert:LastErrorText())

    end

    gen:SetX509Cert(cert,true)

    gen:setKeyInfoType("X509Data")
    gen:setX509Type("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.
    local sbXml = chilkat.newStringBuilder{}

    --  The Polish government's XmlDSig implementation requires that we reproduce an attribute-sorting error.
    --  (This is an error in the XML canonicalization that is not noticed when both the signature-creation code and signature-verification code use
    --  the same XML canonicalization implementation w/ the bug.)
    gen:setBehaviors("AttributeSortingBug,CompactSignedXml")

    --  Sign the XML...
    success = gen:CreateXmlDSigSb(sbXml)
    if success == false then
        print(gen:LastErrorText())

    end

    --  -----------------------------------------------

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

    print(sbXml:GetAsString())

    --  ----------------------------------------
    --  Verify the signature we just produced...
    local verifier = chilkat.newXmlDSig{}
    success = verifier:LoadSignatureSb(sbXml)
    if success == false then
        print(verifier:LastErrorText())

    end

    local verified = verifier:VerifySignature(true)
    if verified ~= true then
        print(verifier:LastErrorText())

    end

    print("This signature was successfully verified.")

    --  ------------------------------------
    --  Finally, let's extract the .zip from the signed XML, and then unzip the original PIT-11Z.xml from the in-memory zip.
    local xml = chilkat.newXml{}
    xml:LoadSb(sbXml,true)

    --  The base64 image of the PIT-11Z.zip is in the 2nd ds:Object child of the ds:Signature (the ds:Signature is the root element of the signed XML).
    --  (ds:Object[0] would be the 1st ds:Object child.  Index 1 is the 2nd ds:Object child.)
    local strZipBase64 = xml:GetChildContent("ds:Object[1]")

    bdZip:Clear()
    bdZip:AppendEncoded(strZipBase64,"base64")
    if bdZip:NumBytes() == 0 then
        print("Something went wrong.. we dont' have any data..")

    end

    success = zip:OpenBd(bdZip)
    if success == false then
        print(zip:LastErrorText())

    end

    --  Get the 1st file in the zip, which should be the PIT-11Z.xml
    local entry = chilkat.newZipEntry{}
    success = zip:EntryAt(0,entry)
    if success == false then
        print("Zip contains no files...")

    end

    --  Get the XML:
    local origXml = entry:UnzipToString(0,"utf-8")
    print("Original XML extracted from base64 zip:")
    print(origXml)