Digital signature on xml string

Question

Hello
I'm trying to sign an xml string, but when I do so, I receive:
HIERARCHY_REQUEST_ERR: An attempt was made to insert a node where it is not permitted.
     at com.sun.org.apache.xerces.internal.dom.CoreDocumentImpl.insertBefore(Unknown Source)
     at org.jcp.xml.dsig.internal.dom.DOMXMLSignature.marshal(Unknown Source)
     at org.jcp.xml.dsig.internal.dom.DOMXMLSignature.sign(Unknown Source)
     at com.azry.ess.service.mof.InboundMessageUtils.sign(InboundMessageUtils.java:139)
     at com.azry.ess.service.mof.Services.getPaymentString(Services.java:187)
     at com.azry.ess.service.mof.Services.main(Services.java:61)
the string looks like this:
<Object Id="PAYMENTS"><PAYMENTS xmlns=""><Payment><PaymentIdA></PaymentIdA><PaymentIdB>aa</PaymentIdB><SrcBank>bb</SrcBank><SrcAccount>cc</SrcAccount><PayerId>dd</PayerId><PayerName>Dato</PayerName><TaxPayerId>00022023</TaxPayerId><TaxPayerName></TaxPayerName><ReceiverName>mof</ReceiverName><AdditinalInfo>racxa</AdditinalInfo><Amount>521</Amount><TreasuryCode>hello</TreasuryCode><PaymentTime>hi</PaymentTime><PaymentChannel>ib</PaymentChannel></Payment></PAYMENTS></Object>
and here's the code
          XMLSignatureFactory fac = XMLSignatureFactory.getInstance("DOM");
          Reference ref = fac.newReference("", fac.newDigestMethod(DigestMethod.SHA1, null));
          CanonicalizationMethod canonicalizationMethod =
                fac.newCanonicalizationMethod(
                CanonicalizationMethod.INCLUSIVE_WITH_COMMENTS,
                (C14NMethodParameterSpec) null);
          SignatureMethod signatureMethod = fac.newSignatureMethod(
                SignatureMethod.RSA_SHA1, null);
          SignedInfo si = fac.newSignedInfo(
                canonicalizationMethod, signatureMethod,
                Collections.nCopies(1, ref));
          KeyInfoFactory kif = fac.getKeyInfoFactory();
          KeyValue kv = kif.newKeyValue(getPeerPublicKey());
          KeyInfo ki = kif.newKeyInfo(Collections.singletonList(kv));
          XMLSignature signature = fac.newXMLSignature(si, ki);
          DOMSignContext sc = new DOMSignContext(getPeerPrivateKey(), doc);
          signature.sign(sc);any ideas? :S
thanks

Answer 1

Thanks for the reply
I'm generating that xml using a simple StringBuilder. here's the code
          StringBuilder sb = new StringBuilder();
          sb.append("<Object Id=\"PAYMENTS\"><PAYMENTS xmlns=\"\"><Payment><PaymentIdA></PaymentIdA><PaymentIdB>");
          sb.append(paymentId);
          sb.append("</PaymentIdB><SrcBank>");
          sb.append(srcBankCode);
          sb.append("</SrcBank><SrcAccount>");
          sb.append(srcBankAccount);
          sb.append("</SrcAccount><PayerId>");
          sb.append(payerId);
          sb.append("</PayerId><PayerName>");
          sb.append(payerName);
          sb.append("</PayerName><TaxPayerId>");
          sb.append(taxPayerId);
          sb.append("</TaxPayerId><TaxPayerName>");
          sb.append("</TaxPayerName><ReceiverName>");
          sb.append(receiverName);
          sb.append("</ReceiverName><AdditinalInfo>");
          sb.append(additionalInfo);
          sb.append("</AdditinalInfo><Amount>");
          sb.append(amount);
          sb.append("</Amount><TreasuryCode>");
          sb.append(treasuryCode);
          sb.append("</TreasuryCode><PaymentTime>");
          sb.append(paymentTime);
          sb.append("</PaymentTime><PaymentChannel>");
          sb.append(paymentChannel);
          sb.append("</PaymentChannel></Payment></PAYMENTS></Object>");
          Document doc = InboundMessageUtils.parseInboundMessage(sb.toString());
          org.w3c.dom.Node n = InboundMessageUtils.sign(InboundMessageUtils.getPeerPrivateKey(), doc);
     public static Document parseInboundMessage(String message) throws Exception {
          DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
          dbf.setNamespaceAware(true);
          InputStream is = new ByteArrayInputStream(message.getBytes(Charset
                    .forName("UTF-8")));
          Document newDoc = dbf.newDocumentBuilder().parse(is);
          return newDoc;
     public static void sign(PrivateKey expectedKey, Document doc) throws Exception{
          XMLSignatureFactory signatureFactory = XMLSignatureFactory
                    .getInstance("DOM");
          XMLSignatureFactory fac = XMLSignatureFactory.getInstance("DOM");
          Reference ref = fac.newReference("", fac.newDigestMethod(DigestMethod.SHA1, null));
          CanonicalizationMethod canonicalizationMethod =
                fac.newCanonicalizationMethod(
                CanonicalizationMethod.INCLUSIVE_WITH_COMMENTS,
                (C14NMethodParameterSpec) null);
          SignatureMethod signatureMethod = fac.newSignatureMethod(
                SignatureMethod.RSA_SHA1, null);
          SignedInfo si = fac.newSignedInfo(
                canonicalizationMethod, signatureMethod,
                Collections.nCopies(1, ref));
          KeyInfoFactory kif = fac.getKeyInfoFactory();
          KeyValue kv = kif.newKeyValue(getPeerPublicKey());
          KeyInfo ki = kif.newKeyInfo(Collections.singletonList(kv));
          XMLSignature signature = fac.newXMLSignature(si, ki);
          DOMSignContext sc = new DOMSignContext(getPeerPrivateKey(), doc);
          signature.sign(sc);
     public static PrivateKey getPeerPrivateKey() throws Exception
          BigInteger modulus = new BigInteger(
          "SomeKey");
          BigInteger exponent = new BigInteger("65537");
          RSAPrivateKeySpec spec = new RSAPrivateKeySpec(modulus, exponent);
          PrivateKey key;
          try {
               KeyFactory kf = KeyFactory.getInstance("RSA");
               key = kf.generatePrivate(spec);
          } catch (NoSuchAlgorithmException e1) {
               throw new Exception(e1);
          } catch (InvalidKeySpecException e1) {
               throw new Exception(e1);
          return key;
     public static PublicKey getPeerPublicKey() throws Exception {
          BigInteger modulus = new BigInteger(
                    "SomeKey");
          BigInteger exponent = new BigInteger("65537");
          RSAPublicKeySpec spec = new RSAPublicKeySpec(modulus, exponent);
          PublicKey key;
          try {
               KeyFactory kf = KeyFactory.getInstance("RSA");
               key = kf.generatePublic(spec);
          } catch (NoSuchAlgorithmException e1) {
               throw new Exception(e1);
          } catch (InvalidKeySpecException e1) {
               throw new Exception(e1);
               return key;
     }Any idea? :S