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Xbase++ 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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LOCAL nSuccess
LOCAL oSbXmlToZip
LOCAL oZip
LOCAL oBdZip
LOCAL oGen
LOCAL oObject1
LOCAL oCert
LOCAL oSbXml
LOCAL oVerifier
LOCAL nVerified
LOCAL oXml
LOCAL cStrZipBase64
LOCAL oEntry
LOCAL cOrigXml

nSuccess := 0

//  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).
oSbXmlToZip := CreateObject("Chilkat.StringBuilder")
nSuccess := oSbXmlToZip:LoadFile("qa_data/xml/PIT-11Z.xml", "utf-8")
IF (nSuccess != 1)
    ? "Failed to load the XML to be zipped."
    oSbXmlToZip:destroy()
    RETURN
ENDIF

oZip := CreateObject("Chilkat.Zip")

//  Initialize the zip object. No file is created in this call.
//  It should always return 1.
nSuccess := oZip:NewZip("PIT-11Z.zip")

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

//  Write the zip to a BinData object.
oBdZip := CreateObject("Chilkat.BinData")
oZip:WriteBd(oBdZip)
//  The contents of the bdZip will be retrieved in base64 format when needed below..

oGen := CreateObject("Chilkat.XmlDSigGen")

oGen:SigLocation := ""
oGen:SigLocationMod := 0

oGen:SigId := "Signature_2a8df7f8-b958-40cc-83f6-edb53b837347_19"
oGen:SigNamespacePrefix := "ds"
oGen:SigNamespaceUri := "http://www.w3.org/2000/09/xmldsig#"
oGen:SigValueId := "SignatureValue_2a8df7f8-b958-40cc-83f6-edb53b837347_52"
oGen:SignedInfoId := "SignedInfo_2a8df7f8-b958-40cc-83f6-edb53b837347_41"
oGen:SignedInfoCanonAlg := "C14N"
oGen:SignedInfoDigestMethod := "sha1"

//  Set the KeyInfoId before adding references..
oGen:KeyInfoId := "KeyInfo_2a8df7f8-b958-40cc-83f6-edb53b837347_24"

//  Create an Object to be added to the Signature.
oObject1 := CreateObject("Chilkat.Xml")
oObject1:Tag := "xades:QualifyingProperties"
oObject1:AddAttribute("xmlns:xades", "http://uri.etsi.org/01903/v1.3.2#")
oObject1:AddAttribute("Id", "QualifyingProperties_2a8df7f8-b958-40cc-83f6-edb53b837347_43")
oObject1:AddAttribute("Target", "#Signature_2a8df7f8-b958-40cc-83f6-edb53b837347_19")
oObject1:UpdateAttrAt("xades:SignedProperties", 1, "Id", "SignedProperties_2a8df7f8-b958-40cc-83f6-edb53b837347_4e")
oObject1:UpdateAttrAt("xades:SignedProperties|xades:SignedSignatureProperties", 1, "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.
oObject1: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
oObject1:UpdateAttrAt("xades:SignedProperties|xades:SignedSignatureProperties|xades:SigningCertificateV2|xades:Cert|xades:CertDigest|ds:DigestMethod", 1, "Algorithm", "http://www.w3.org/2000/09/xmldsig#sha1")
oObject1:UpdateChildContent("xades:SignedProperties|xades:SignedSignatureProperties|xades:SigningCertificateV2|xades:Cert|xades:CertDigest|ds:DigestValue", "TO BE GENERATED BY CHILKAT")
oObject1:UpdateChildContent("xades:SignedProperties|xades:SignedSignatureProperties|xades:SigningCertificateV2|xades:Cert|xades:IssuerSerialV2", "TO BE GENERATED BY CHILKAT")
oObject1:UpdateAttrAt("xades:SignedProperties|xades:SignedDataObjectProperties", 1, "Id", "SignedDataObjectProperties_2a8df7f8-b958-40cc-83f6-edb53b837347_4b")
oObject1:UpdateAttrAt("xades:SignedProperties|xades:SignedDataObjectProperties|xades:DataObjectFormat", 1, "ObjectReference", "#Reference1_2a8df7f8-b958-40cc-83f6-edb53b837347_27")
oObject1:UpdateChildContent("xades:SignedProperties|xades:SignedDataObjectProperties|xades:DataObjectFormat|xades:Description", "MIME-Version: 1.0" + Chr(13) + Chr(10) + "Content-Type: application/zip" + Chr(13) + Chr(10) + "Content-Transfer-Encoding: binary" + Chr(13) + Chr(10) + "Content-Disposition: filename="PIT-11Z.zip"")
oObject1:UpdateAttrAt("xades:SignedProperties|xades:SignedDataObjectProperties|xades:DataObjectFormat|xades:ObjectIdentifier|xades:Identifier", 1, "Qualifier", "OIDAsURI")
oObject1: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")
oObject1:UpdateChildContent("xades:SignedProperties|xades:SignedDataObjectProperties|xades:DataObjectFormat|xades:ObjectIdentifier|xades:Description", "Opis formatu dokumentu oraz jego pelna nazwa")
oObject1:UpdateChildContent("xades:SignedProperties|xades:SignedDataObjectProperties|xades:DataObjectFormat|xades:ObjectIdentifier|xades:DocumentationReferences|xades:DocumentationReference", "http://www.certum.pl/OIDAsURI/signedFile.pdf")
oObject1:UpdateChildContent("xades:SignedProperties|xades:SignedDataObjectProperties|xades:DataObjectFormat|xades:MimeType", "application/zip")
oObject1:UpdateChildContent("xades:SignedProperties|xades:SignedDataObjectProperties|xades:CommitmentTypeIndication|xades:CommitmentTypeId|xades:Identifier", "http://uri.etsi.org/01903/v1.2.2#ProofOfApproval")
oObject1:UpdateChildContent("xades:SignedProperties|xades:SignedDataObjectProperties|xades:CommitmentTypeIndication|xades:AllSignedDataObjects", "")
oObject1:UpdateAttrAt("xades:UnsignedProperties", 1, "Id", "UnsignedProperties_2a8df7f8-b958-40cc-83f6-edb53b837347_55")

//  Emit XML in compact (single-line) format to avoid whitespace problems.
oObject1:EmitCompact := 1
oGen:AddObject("", oObject1:GetXml(), "", "")

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

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

//  -------- Reference 2 --------
oGen:AddObjectRef("SignedProperties_2a8df7f8-b958-40cc-83f6-edb53b837347_4e", "sha1", "", "", "http://uri.etsi.org/01903#SignedProperties")
oGen: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)
oCert := CreateObject("Chilkat.Cert")
nSuccess := oCert:LoadPfxFile("qa_data/pfx/cert_test123.pfx", "test123")
IF (nSuccess == 0)
    ? oCert:LastErrorText
    oSbXmlToZip:destroy()
    oZip:destroy()
    oBdZip:destroy()
    oGen:destroy()
    oObject1:destroy()
    oCert:destroy()
    RETURN
ENDIF

oGen:SetX509Cert(oCert, 1)

oGen:KeyInfoType := "X509Data"
oGen:X509Type := "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.
oSbXml := CreateObject("Chilkat.StringBuilder")

//  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.)
oGen:Behaviors := "AttributeSortingBug,CompactSignedXml"

//  Sign the XML...
nSuccess := oGen:CreateXmlDSigSb(oSbXml)
IF (nSuccess == 0)
    ? oGen:LastErrorText
    oSbXmlToZip:destroy()
    oZip:destroy()
    oBdZip:destroy()
    oGen:destroy()
    oObject1:destroy()
    oCert:destroy()
    oSbXml:destroy()
    RETURN
ENDIF

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

//  Save the signed XML to a file.
nSuccess := oSbXml:WriteFile("qa_output/signedXml.xml", "utf-8", 0)

? oSbXml:GetAsString()

//  ----------------------------------------
//  Verify the signature we just produced...
oVerifier := CreateObject("Chilkat.XmlDSig")
nSuccess := oVerifier:LoadSignatureSb(oSbXml)
IF (nSuccess == 0)
    ? oVerifier:LastErrorText
    oSbXmlToZip:destroy()
    oZip:destroy()
    oBdZip:destroy()
    oGen:destroy()
    oObject1:destroy()
    oCert:destroy()
    oSbXml:destroy()
    oVerifier:destroy()
    RETURN
ENDIF

nVerified := oVerifier:VerifySignature(1)
IF (nVerified != 1)
    ? oVerifier:LastErrorText
    oSbXmlToZip:destroy()
    oZip:destroy()
    oBdZip:destroy()
    oGen:destroy()
    oObject1:destroy()
    oCert:destroy()
    oSbXml:destroy()
    oVerifier:destroy()
    RETURN
ENDIF

? "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.
oXml := CreateObject("Chilkat.Xml")
oXml:LoadSb(oSbXml, 1)

//  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.)
cStrZipBase64 := oXml:GetChildContent("ds:Object[1]")

oBdZip:Clear()
oBdZip:AppendEncoded(cStrZipBase64, "base64")
IF (oBdZip:NumBytes == 0)
    ? "Something went wrong.. we dont' have any data.."
    oSbXmlToZip:destroy()
    oZip:destroy()
    oBdZip:destroy()
    oGen:destroy()
    oObject1:destroy()
    oCert:destroy()
    oSbXml:destroy()
    oVerifier:destroy()
    oXml:destroy()
    RETURN
ENDIF

nSuccess := oZip:OpenBd(oBdZip)
IF (nSuccess == 0)
    ? oZip:LastErrorText
    oSbXmlToZip:destroy()
    oZip:destroy()
    oBdZip:destroy()
    oGen:destroy()
    oObject1:destroy()
    oCert:destroy()
    oSbXml:destroy()
    oVerifier:destroy()
    oXml:destroy()
    RETURN
ENDIF

//  Get the 1st file in the zip, which should be the PIT-11Z.xml
oEntry := CreateObject("Chilkat.ZipEntry")
nSuccess := oZip:EntryAt(0, oEntry)
IF (nSuccess == 0)
    ? "Zip contains no files..."
    oSbXmlToZip:destroy()
    oZip:destroy()
    oBdZip:destroy()
    oGen:destroy()
    oObject1:destroy()
    oCert:destroy()
    oSbXml:destroy()
    oVerifier:destroy()
    oXml:destroy()
    oEntry:destroy()
    RETURN
ENDIF

//  Get the XML:
cOrigXml := oEntry:UnzipToString(0, "utf-8")
? "Original XML extracted from base64 zip:"
? cOrigXml

oSbXmlToZip:destroy()
oZip:destroy()
oBdZip:destroy()
oGen:destroy()
oObject1:destroy()
oCert:destroy()
oSbXml:destroy()
oVerifier:destroy()
oXml:destroy()
oEntry:destroy()