(Perl) Create JPK VAT metadata XML

Demonstrates how to create the JPK VAT metadata XML (InitUpload) that will be signed using XADES.

Note: This example requires Chilkat v11.0.0 or greater.

Chilkat Perl Downloads Perl Module for Windows, MacOS, Linux, Alpine Linux

use chilkat();

$success = 0;

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

# First build an InitUpload XML template

# Use this online tool to generate the code from the sample XML below: 
# Generate Code to Create XML

# <InitUpload xmlns="http://e-dokumenty.mf.gov.pl">
#     <DocumentType>JPK</DocumentType>
#     <Version>01.02.01.20160617</Version>
#     <EncryptionKey algorithm="RSA" encoding="Base64" mode="ECB" padding="PKCS#1">F9EhKFec...uWqAWUIg==</EncryptionKey>
#     <DocumentList>
#         <Document>
#             <FormCode schemaVersion="1-1" systemCode="JPK_VAT (3)">JPK_VAT</FormCode>
#             <FileName>JPK_VAT_3_v1-1_20181201.xml</FileName>
#             <ContentLength>8736</ContentLength>
#             <HashValue algorithm="SHA-256" encoding="Base64">JFDI1pItwh6dj/Xe1uts/x61qnjZ4DLHpkZMhmf1oKQ=</HashValue>
#             <FileSignatureList filesNumber="1">
#                 <Packaging>
#                     <SplitZip mode="zip" type="split"/>
#                 </Packaging>
#                 <Encryption>
#                     <AES block="16" mode="CBC" padding="PKCS#7" size="256">
#                         <IV bytes="16" encoding="Base64">z64oN9zXHt1+S3XACRSCYw==</IV>
#                     </AES>
#                 </Encryption>
#                 <FileSignature>
#                     <OrdinalNumber>1</OrdinalNumber>
#                     <FileName>JPK_VAT_3_v1-1_20181201-000.xml.zip.aes</FileName>
#                     <ContentLength>16</ContentLength>
#                     <HashValue algorithm="MD5" encoding="Base64">5NX0q1935fvMjLFV7E1yDw==</HashValue>
#                 </FileSignature>
#             </FileSignatureList>
#         </Document>
#     </DocumentList>
# </InitUpload>

$xml = chilkat::CkXml->new();
$xml->put_Tag("InitUpload");
$xml->AddAttribute("xmlns","http://e-dokumenty.mf.gov.pl");
$xml->UpdateChildContent("DocumentType","JPK");
$xml->UpdateChildContent("Version","01.02.01.20160617");
$xml->UpdateAttrAt("EncryptionKey",1,"algorithm","RSA");
$xml->UpdateAttrAt("EncryptionKey",1,"encoding","Base64");
$xml->UpdateAttrAt("EncryptionKey",1,"mode","ECB");
$xml->UpdateAttrAt("EncryptionKey",1,"padding","PKCS#1");
$xml->UpdateChildContent("EncryptionKey","TO BE DETERMINED");
$xml->UpdateAttrAt("DocumentList|Document|FormCode",1,"schemaVersion","1-1");
$xml->UpdateAttrAt("DocumentList|Document|FormCode",1,"systemCode","JPK_VAT (3)");
$xml->UpdateChildContent("DocumentList|Document|FormCode","JPK_VAT");
$xml->UpdateChildContent("DocumentList|Document|FileName","JPK_VAT_3_v1-1_20181201.xml");
$xml->UpdateChildContent("DocumentList|Document|ContentLength","9999");
$xml->UpdateAttrAt("DocumentList|Document|HashValue",1,"algorithm","SHA-256");
$xml->UpdateAttrAt("DocumentList|Document|HashValue",1,"encoding","Base64");
$xml->UpdateChildContent("DocumentList|Document|HashValue","TO BE DETERMINED");
$xml->UpdateAttrAt("DocumentList|Document|FileSignatureList",1,"filesNumber","1");
$xml->UpdateAttrAt("DocumentList|Document|FileSignatureList|Packaging|SplitZip",1,"mode","zip");
$xml->UpdateAttrAt("DocumentList|Document|FileSignatureList|Packaging|SplitZip",1,"type","split");
$xml->UpdateAttrAt("DocumentList|Document|FileSignatureList|Encryption|AES",1,"block","16");
$xml->UpdateAttrAt("DocumentList|Document|FileSignatureList|Encryption|AES",1,"mode","CBC");
$xml->UpdateAttrAt("DocumentList|Document|FileSignatureList|Encryption|AES",1,"padding","PKCS#7");
$xml->UpdateAttrAt("DocumentList|Document|FileSignatureList|Encryption|AES",1,"size","256");
$xml->UpdateAttrAt("DocumentList|Document|FileSignatureList|Encryption|AES|IV",1,"bytes","16");
$xml->UpdateAttrAt("DocumentList|Document|FileSignatureList|Encryption|AES|IV",1,"encoding","Base64");
$xml->UpdateChildContent("DocumentList|Document|FileSignatureList|Encryption|AES|IV","TO BE DETERMINED");
$xml->UpdateChildContent("DocumentList|Document|FileSignatureList|FileSignature|OrdinalNumber","1");
$xml->UpdateChildContent("DocumentList|Document|FileSignatureList|FileSignature|FileName","JPK_VAT_3_v1-1_20181201-000.xml.zip.aes");
$xml->UpdateChildContent("DocumentList|Document|FileSignatureList|FileSignature|ContentLength","9999");
$xml->UpdateAttrAt("DocumentList|Document|FileSignatureList|FileSignature|HashValue",1,"algorithm","MD5");
$xml->UpdateAttrAt("DocumentList|Document|FileSignatureList|FileSignature|HashValue",1,"encoding","Base64");
$xml->UpdateChildContent("DocumentList|Document|FileSignatureList|FileSignature|HashValue","TO BE DETERMINED");

# ------------------------------------------------------------
# Step 1: Load our JPK_VAT XML and update the DocumentList|Document|HashValue
# and DocumentList|Document|ContentLength
$bdXml = chilkat::CkBinData->new();
$success = $bdXml->LoadFile("qa_data/xml_dsig/jpk_vat/JPK_VAT_3_v1-1_20181201-000.xml");
if ($success != 1) {
    print "Failed to load XML file." . "\r\n";
    exit;
}

$xml->UpdateChildContentInt("DocumentList|Document|ContentLength",$bdXml->get_NumBytes());

$crypt = chilkat::CkCrypt2->new();
$crypt->put_HashAlgorithm("sha256");
$crypt->put_EncodingMode("base64");
$xml->UpdateChildContent("DocumentList|Document|HashValue",$crypt->hashBdENC($bdXml));

# ------------------------------------------------------------
# Step 2: Create a Zip archive containing the XML.
$zip = chilkat::CkZip->new();
# The filename we pass here doesn't matter because we won't actually be creating a .zip file.
$zip->NewZip("anything.zip");
$zip->AddBd("JPK_VAT_3_v1-1_20181201-000.xml",$bdXml);
# Write the .zip file to a BinData object.
$bdZip = chilkat::CkBinData->new();
$zip->WriteBd($bdZip);

# ------------------------------------------------------------
# Step 3: Generate a random 256-bit AES key (32-bytes)
$prng = chilkat::CkPrng->new();
$bdAesKey = chilkat::CkBinData->new();
$prng->GenRandomBd(32,$bdAesKey);
$ivBytes = $prng->genRandom(16,"base64");

# Store the IV (base64 string) in the XML.
$xml->UpdateChildContent("DocumentList|Document|FileSignatureList|Encryption|AES|IV",$ivBytes);

# ------------------------------------------------------------
# Step 4: AES encrypt our zip archive (the contents of bdZip)
$crypt->put_CipherMode("cbc");
$crypt->put_KeyLength(256);
$crypt->put_CryptAlgorithm("aes");
$crypt->put_PaddingScheme(0);
$crypt->SetEncodedIV($ivBytes,"base64");
$crypt->SetEncodedKey($bdAesKey->getEncoded("base64"),"base64");
# AES by definition has a block size of 16.
$crypt->EncryptBd($bdZip);

# bdZip now contains the AES encrypted data. 
# Note: This is NOT the same as a zip where the contents are AES encrypted.
# In that case, we have an unencrypted zip structure with AES encrypted files within.
# In our case, the entire zip file image is encrypted.

# Save the bdZip to a file.  This is what will get sent to e-dokumenty.mf.gov.pl
$success = $bdZip->WriteFile("qa_output/JPK_VAT_3_v1-1_20181201-000.xml.zip.aes");
$xml->UpdateChildContentInt("DocumentList|Document|FileSignatureList|FileSignature|ContentLength",$bdZip->get_NumBytes());

# ------------------------------------------------------------
# Step 4: RSA Encrypt the AES key using the public key certificate provided by the Ministry of Finance
$cert = chilkat::CkCert->new();
$success = $cert->LoadFromFile("qa_data/pem/mf_public_rsa.pem");
if ($success == 0) {
    print $cert->lastErrorText() . "\r\n";
    exit;
}

$pubKey = chilkat::CkPublicKey->new();
$cert->GetPublicKey($pubKey);

$rsa = chilkat::CkRsa->new();
$rsa->UsePublicKey($pubKey);

$rsa->put_EncodingMode("base64");
$rsa->put_LittleEndian(0);
# in-place RSA encrypt the contents of bdAesKey.
$rsa->EncryptBd($bdAesKey,0);
$xml->UpdateChildContent("EncryptionKey",$bdAesKey->getEncoded("base64"));

# Step 5: We forgot to get the MD5 hash of the AES encrypted zip.
# (I'm assuming we need the MD5 of the encrypted zip as opposed to the MD5 of the pre-encrypted zip..)
$crypt->put_HashAlgorithm("md5");
$xml->UpdateChildContent("DocumentList|Document|FileSignatureList|FileSignature|HashValue",$crypt->hashBdENC($bdZip));

# At this point, the XML is prepared and the AES encrypted image of the zip file is written
# to a file (and also in bdZip).
$finalXml = $xml->getXml();
print $finalXml . "\r\n";

$xml->SaveXml("qa_output/jpk_vat.xml");

print "Finished." . "\r\n";