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Java Requires Chilkat v11.0.0+

Create JPK VAT metadata XML

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

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Chilkat2 Java
import com.chilkatsoft.chilkat2.BinData;
import com.chilkatsoft.chilkat2.Cert;
import com.chilkatsoft.chilkat2.ChilkatException;
import com.chilkatsoft.chilkat2.Crypt2;
import com.chilkatsoft.chilkat2.Prng;
import com.chilkatsoft.chilkat2.PublicKey;
import com.chilkatsoft.chilkat2.Rsa;
import com.chilkatsoft.chilkat2.Xml;
import com.chilkatsoft.chilkat2.Zip;

public class ChilkatExample {

    public static void main(String[] args) {
        // 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 xml = new Xml();
        xml.setTag("InitUpload");
        xml.addAttribute("xmlns", "http://e-dokumenty.mf.gov.pl");
        xml.updateChildContent("DocumentType", "JPK");
        xml.updateChildContent("Version", "01.02.01.20160617");
        xml.updateAttrAt("EncryptionKey", true, "algorithm", "RSA");
        xml.updateAttrAt("EncryptionKey", true, "encoding", "Base64");
        xml.updateAttrAt("EncryptionKey", true, "mode", "ECB");
        xml.updateAttrAt("EncryptionKey", true, "padding", "PKCS#1");
        xml.updateChildContent("EncryptionKey", "TO BE DETERMINED");
        xml.updateAttrAt("DocumentList|Document|FormCode", true, "schemaVersion", "1-1");
        xml.updateAttrAt("DocumentList|Document|FormCode", true, "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", true, "algorithm", "SHA-256");
        xml.updateAttrAt("DocumentList|Document|HashValue", true, "encoding", "Base64");
        xml.updateChildContent("DocumentList|Document|HashValue", "TO BE DETERMINED");
        xml.updateAttrAt("DocumentList|Document|FileSignatureList", true, "filesNumber", "1");
        xml.updateAttrAt("DocumentList|Document|FileSignatureList|Packaging|SplitZip", true, "mode", "zip");
        xml.updateAttrAt("DocumentList|Document|FileSignatureList|Packaging|SplitZip", true, "type", "split");
        xml.updateAttrAt("DocumentList|Document|FileSignatureList|Encryption|AES", true, "block", "16");
        xml.updateAttrAt("DocumentList|Document|FileSignatureList|Encryption|AES", true, "mode", "CBC");
        xml.updateAttrAt("DocumentList|Document|FileSignatureList|Encryption|AES", true, "padding", "PKCS#7");
        xml.updateAttrAt("DocumentList|Document|FileSignatureList|Encryption|AES", true, "size", "256");
        xml.updateAttrAt("DocumentList|Document|FileSignatureList|Encryption|AES|IV", true, "bytes", "16");
        xml.updateAttrAt("DocumentList|Document|FileSignatureList|Encryption|AES|IV", true, "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", true, "algorithm", "MD5");
        xml.updateAttrAt("DocumentList|Document|FileSignatureList|FileSignature|HashValue", true, "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
        BinData bdXml = new BinData();
        try {
            bdXml.loadFile("qa_data/xml_dsig/jpk_vat/JPK_VAT_3_v1-1_20181201-000.xml");
        } catch (ChilkatException e) {
            System.out.println("Failed to load XML file.");
            return;
        }

        xml.updateChildContentInt("DocumentList|Document|ContentLength", bdXml.getNumBytes());

        Crypt2 crypt = new Crypt2();
        crypt.setHashAlgorithm("sha256");
        crypt.setEncodingMode("base64");
        xml.updateChildContent("DocumentList|Document|HashValue", crypt.hashBdENC(bdXml));

        // ------------------------------------------------------------
        // Step 2: Create a Zip archive containing the XML.
        Zip zip = new Zip();
        // 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.
        BinData bdZip = new BinData();
        zip.writeBd(bdZip);

        // ------------------------------------------------------------
        // Step 3: Generate a random 256-bit AES key (32-bytes)
        Prng prng = new Prng();
        BinData bdAesKey = new BinData();
        prng.genRandomBd(32, bdAesKey);
        String 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.setCipherMode("cbc");
        crypt.setKeyLength(256);
        crypt.setCryptAlgorithm("aes");
        crypt.setPaddingScheme(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
        bdZip.writeFile("qa_output/JPK_VAT_3_v1-1_20181201-000.xml.zip.aes");
        xml.updateChildContentInt("DocumentList|Document|FileSignatureList|FileSignature|ContentLength", bdZip.getNumBytes());

        // ------------------------------------------------------------
        // Step 4: RSA Encrypt the AES key using the public key certificate provided by the Ministry of Finance
        Cert cert = new Cert();
        try {
            cert.loadFromFile("qa_data/pem/mf_public_rsa.pem");
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        PublicKey pubKey = new PublicKey();
        cert.getPublicKey(pubKey);

        Rsa rsa = new Rsa();
        rsa.usePublicKey(pubKey);

        rsa.setEncodingMode("base64");
        rsa.setLittleEndian(false);
        // in-place RSA encrypt the contents of bdAesKey.
        rsa.encryptBd(bdAesKey, false);
        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.setHashAlgorithm("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).
        String finalXml = xml.getXml();
        System.out.println(finalXml);

        xml.saveXml("qa_output/jpk_vat.xml");

        System.out.println("Finished.");
    }
}