Support custom XML element IDs

src/main/java/xades4j/production/DefaultElementIdGeneratorFactory.java

@@ -0,0 +1,31 @@
+/*
+ * XAdES4j - A Java library for generation and verification of XAdES signatures.
+ * Copyright (C) 2024 Luis Goncalves.
+ *
+ * XAdES4j is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU Lesser General Public License as published by the Free
+ * Software Foundation; either version 3 of the License, or any later version.
+ *
+ * XAdES4j is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License along
+ * with XAdES4j. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package xades4j.production;
+
+import java.util.UUID;
+
+final class DefaultElementIdGeneratorFactory implements ElementIdGeneratorFactory
+{
+    @Override
+    public ElementIdGenerator create()
+    {
+        return (namespace, name) -> {
+            return name.toLowerCase() + "-" + UUID.randomUUID();
+        };
+    }
+}

src/main/java/xades4j/production/DefaultProductionBindingsModule.java

@@ -74,6 +74,7 @@ protected void configure()
         bind(HttpTsaConfiguration.class).toProvider(() -> {
             throw new IllegalStateException("HttpTsaConfiguration must be configured in the profile in order to use an HTTP-based time-stamp token provider.");
         });
+        bind(ElementIdGeneratorFactory.class).to(DefaultElementIdGeneratorFactory.class);
 
         // PropertiesDataObjectsGenerator is not configurable but the individual
         // generators may have dependencies.

src/main/java/xades4j/production/ElementIdGenerator.java

@@ -0,0 +1,57 @@
+/*
+ * XAdES4j - A Java library for generation and verification of XAdES signatures.
+ * Copyright (C) 2024 Luis Goncalves.
+ *
+ * XAdES4j is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU Lesser General Public License as published by the Free
+ * Software Foundation; either version 3 of the License, or any later version.
+ *
+ * XAdES4j is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License along
+ * with XAdES4j. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package xades4j.production;
+
+import java.util.UUID;
+
+/**
+ * Generates IDs for XML elements in a given signing operation.
+ */
+public interface ElementIdGenerator
+{
+    /**
+     * Generate an ID for an XML element.
+     *
+     * @param namespace the element namespace
+     * @param name      the element name
+     * @return the ID
+     */
+    String generateId(String namespace, String name);
+
+    /**
+     * Gets a {@link ElementIdGenerator} that uses a UUID for each requested ID.
+     */
+    static ElementIdGenerator uuid()
+    {
+        return uuid(null, null);
+    }
+
+    /**
+     * Gets a {@link ElementIdGenerator} that uses a UUID for each requested ID, optionally using a constant prefix
+     * and/or suffix.
+     *
+     * @param prefix the ID prefix (may be null)
+     * @param suffix the ID suffix (may be null)
+     */
+    static ElementIdGenerator uuid(String prefix, String suffix)
+    {
+        final String p = prefix == null ? "" : prefix;
+        final String s = suffix == null ? "" : suffix;
+        return (ns, n) -> p + UUID.randomUUID() + s;
+    }
+}

src/main/java/xades4j/production/ElementIdGeneratorFactory.java

@@ -0,0 +1,55 @@
+/*
+ * XAdES4j - A Java library for generation and verification of XAdES signatures.
+ * Copyright (C) 2024 Luis Goncalves.
+ *
+ * XAdES4j is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU Lesser General Public License as published by the Free
+ * Software Foundation; either version 3 of the License, or any later version.
+ *
+ * XAdES4j is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License along
+ * with XAdES4j. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package xades4j.production;
+
+import java.util.UUID;
+
+/**
+ * A factory of {@link ElementIdGenerator}.
+ */
+public interface ElementIdGeneratorFactory
+{
+    /**
+     * Create a new {@link ElementIdGenerator}. This method is invoked once for each signing operation and the returned
+     * instance is used to obtain element IDs during that operation. This allows for scenarios where all the element IDs
+     * share a common base.
+     *
+     * @return the ID generator
+     */
+    ElementIdGenerator create();
+
+    /**
+     * Gets a {@link ElementIdGeneratorFactory} that uses a UUID for each requested ID.
+     */
+    static ElementIdGeneratorFactory uuid()
+    {
+        return ElementIdGenerator::uuid;
+    }
+
+    /**
+     * Gets a {@link ElementIdGeneratorFactory} that uses a UUID for each requested ID, optionally using a constant
+     * prefix and/or suffix.
+     *
+     * @param prefix the ID prefix (may be null)
+     * @param suffix the ID suffix (may be null)
+     */
+    static ElementIdGeneratorFactory uuid(String prefix, String suffix)
+    {
+        return () -> ElementIdGenerator.uuid(prefix, suffix);
+    }
+}

src/main/java/xades4j/production/KeyInfoBuilder.java

@@ -32,6 +32,8 @@
 import xades4j.utils.TransformUtils;
 import xades4j.xml.marshalling.algorithms.AlgorithmsParametersMarshallingProvider;
 
+import static xades4j.production.SignerBES.idFor;
+
 /**
  * Helper class that creates the {@code ds:KeyInfo} element accordingly to some
  * signature options. The signing certificate validity and key usages are
@@ -60,15 +62,16 @@ class KeyInfoBuilder
 
     void buildKeyInfo(
             List<X509Certificate> signingCertificateChain,
-            XMLSignature xmlSig) throws KeyingDataException, UnsupportedAlgorithmException
+            XMLSignature xmlSig,
+            ElementIdGenerator idGenerator) throws KeyingDataException, UnsupportedAlgorithmException
     {
         X509Certificate signingCertificate = getSigningCertificate(signingCertificateChain);
 
         addSigningCertificateElements(signingCertificateChain, signingCertificate, xmlSig);
 
         addPublicKey(signingCertificate, xmlSig);
 
-        addKeyInfoReference(xmlSig);
+        addKeyInfoReference(xmlSig, idGenerator);
     }
 
     private void addSigningCertificateElements(List<X509Certificate> signingCertificateChain, X509Certificate signingCertificate, XMLSignature xmlSig) throws KeyingDataException
@@ -119,13 +122,13 @@ private void addPublicKey(X509Certificate signingCertificate, XMLSignature xmlSi
         }
     }
 
-    private void addKeyInfoReference(XMLSignature xmlSig) throws UnsupportedAlgorithmException
+    private void addKeyInfoReference(XMLSignature xmlSig, ElementIdGenerator idGenerator) throws UnsupportedAlgorithmException
     {
         if (this.basicSignatureOptions.signKeyInfo())
         {
             try
             {
-                String keyInfoId = xmlSig.getId() + "-keyinfo";
+                String keyInfoId = idFor(xmlSig.getKeyInfo(), idGenerator);
                 xmlSig.getKeyInfo().setId(keyInfoId);
 
                 // Use same canonicalization URI as specified in the ds:CanonicalizationMethod for Signature.

src/main/java/xades4j/production/SignedDataObjectsProcessor.java

@@ -40,6 +40,8 @@
 import java.util.Map;
 import java.util.Set;
 
+import static xades4j.production.SignerBES.idFor;
+
 /**
  * Helper class that processes a set of data object descriptions.
  *
@@ -80,7 +82,8 @@ public Result(Map<DataObjectDesc, Reference> referenceMappings, Set<Manifest> ma
      */
     SignedDataObjectsProcessor.Result process(
             SignedDataObjects signedDataObjects,
-            XMLSignature xmlSignature) throws UnsupportedAlgorithmException {
+            XMLSignature xmlSignature,
+            ElementIdGenerator idGenerator) throws UnsupportedAlgorithmException {
         if (xmlSignature.getSignedInfo().getLength() != 0)
         {
             throw new IllegalStateException("XMLSignature already contains references");
@@ -89,19 +92,19 @@ SignedDataObjectsProcessor.Result process(
         return process(
                 signedDataObjects.getDataObjectsDescs(),
                 xmlSignature.getSignedInfo(),
-                xmlSignature.getId(),
                 signedDataObjects.getResourceResolvers(),
                 xmlSignature,
-                false);
+                false,
+                idGenerator);
     }
 
     private SignedDataObjectsProcessor.Result process(
             Collection<? extends DataObjectDesc> dataObjects,
             Manifest container,
-            String idPrefix,
             List<ResourceResolverSpi> resourceResolvers,
             XMLSignature xmlSignature,
-            boolean hasNullURIReference) throws UnsupportedAlgorithmException {
+            boolean hasNullURIReference,
+            ElementIdGenerator idGenerator) throws UnsupportedAlgorithmException {
         Map<DataObjectDesc, Reference> referenceMappings = new IdentityHashMap<>(dataObjects.size());
         Set<Manifest> manifests = new HashSet<>();
 
@@ -134,9 +137,9 @@ else if (dataObjDesc instanceof EnvelopedXmlObject)
                     // If the data object info is a EnvelopedXmlObject we need to create a ds:Object to embed it.
                     // The Reference uri will refer the new ds:Object's id.
                     EnvelopedXmlObject envXmlObj = (EnvelopedXmlObject) dataObjDesc;
-                    String xmlObjId = String.format("%s-object%d", idPrefix, index);
 
                     ObjectContainer xmlObj = new ObjectContainer(container.getDocument());
+                    String xmlObjId = idFor(xmlObj, idGenerator);
                     xmlObj.setId(xmlObjId);
                     xmlObj.appendChild(envXmlObj.getContent());
                     xmlObj.setMimeType(envXmlObj.getMimeType());
@@ -164,17 +167,18 @@ else if (dataObjDesc instanceof EnvelopedManifest)
                     // If the data object info is a EnvelopedManifest we need to create a ds:Manifest and a ds:Object
                     // to embed it. The Reference uri will refer the manifest's id.
                     EnvelopedManifest envManifest = (EnvelopedManifest) dataObjDesc;
-                    String xmlManifestId = String.format("%s-manifest%d", idPrefix, index);
 
                     Manifest xmlManifest = new Manifest(container.getDocument());
+                    String xmlManifestId = idFor(xmlManifest, idGenerator);
                     xmlManifest.setId(xmlManifestId);
+
                     SignedDataObjectsProcessor.Result manifestResult = process(
                             envManifest.getDataObjects(),
                             xmlManifest,
-                            xmlManifestId,
                             resourceResolvers,
                             xmlSignature,
-                            hasNullURIReference);
+                            hasNullURIReference,
+                            idGenerator);
 
                     ObjectContainer xmlObj = new ObjectContainer(container.getDocument());
                     xmlObj.appendChild(xmlManifest.getElement());
@@ -199,12 +203,13 @@ else if (dataObjDesc instanceof EnvelopedManifest)
                         refUri,
                         transforms,
                         digestMethodUri,
-                        String.format("%s-ref%d", idPrefix, index), // id
+                        null,
                         refType);
 
                 // SignedDataObjects and EnvelopedManifest don't allow repeated instances, so there's no
                 // need to check for duplicate entries on the map.
                 Reference ref = container.item(index);
+                ref.setId(idFor(ref, idGenerator));
                 referenceMappings.put(dataObjDesc, ref);
             }
 

src/main/java/xades4j/production/SignerBES.java

@@ -85,6 +85,7 @@ class SignerBES implements XadesSigner
     private final SignedPropertiesMarshaller signedPropsMarshaller;
     private final UnsignedPropertiesMarshaller unsignedPropsMarshaller;
     private final AlgorithmsParametersMarshallingProvider algorithmsParametersMarshaller;
+    private final ElementIdGeneratorFactory idGeneratorFactory;
     /**/
     private final KeyInfoBuilder keyInfoBuilder;
     private final QualifyingPropertiesProcessor qualifPropsProcessor;
@@ -101,13 +102,14 @@ protected SignerBES(
             SignedPropertiesMarshaller signedPropsMarshaller,
             UnsignedPropertiesMarshaller unsignedPropsMarshaller,
             AlgorithmsParametersMarshallingProvider algorithmsParametersMarshaller,
-            X500NameStyleProvider x500NameStyleProvider)
+            X500NameStyleProvider x500NameStyleProvider,
+            ElementIdGeneratorFactory idGeneratorFactory)
     {
         if (ObjectUtils.anyNull(
                 keyingProvider, signatureAlgorithms, basicSignatureOptions,
                 signaturePropsProvider, dataObjPropsProvider, propsDataObjectsGenerator,
                 signedPropsMarshaller, unsignedPropsMarshaller, algorithmsParametersMarshaller,
-                x500NameStyleProvider))
+                x500NameStyleProvider, idGeneratorFactory))
         {
             throw new NullPointerException("One or more arguments are null");
         }
@@ -120,6 +122,7 @@ protected SignerBES(
         this.unsignedPropsMarshaller = unsignedPropsMarshaller;
         this.algorithmsParametersMarshaller = algorithmsParametersMarshaller;
         this.dataObjectDescsProcessor = dataObjectDescsProcessor;
+        this.idGeneratorFactory = idGeneratorFactory;
         this.keyInfoBuilder = new KeyInfoBuilder(basicSignatureOptions, signatureAlgorithms, algorithmsParametersMarshaller, x500NameStyleProvider);
         this.qualifPropsProcessor = new QualifyingPropertiesProcessor(signaturePropsProvider, dataObjPropsProvider);
     }
@@ -154,10 +157,8 @@ public final XadesSignatureResult sign(
         this.basicSignatureOptions.ensureValid();
 
         Document signatureDocument = DOMHelper.getOwnerDocument(referenceNode);
+        ElementIdGenerator idGenerator = this.idGeneratorFactory.create();
 
-        // Generate unique identifiers for the Signature and the SignedProperties.
-        String signatureId = String.format("xmldsig-%s", UUID.randomUUID());
-        String signedPropsId = String.format("%s-signedprops", signatureId);
 
         // Signing certificate chain (may contain only the signing certificate).
         List<X509Certificate> signingCertificateChain = this.keyingProvider.getSigningCertificateChain();
@@ -173,6 +174,7 @@ public final XadesSignatureResult sign(
                 signedDataObjects.getBaseUri(),
                 signingCertificate.getPublicKey().getAlgorithm());
 
+        String signatureId = idFor(signature, idGenerator);
         signature.setId(signatureId);
 
         /* References */
@@ -181,10 +183,11 @@ public final XadesSignatureResult sign(
         // are added to the signature.
         SignedDataObjectsProcessor.Result signedDataObjectsResult = this.dataObjectDescsProcessor.process(
                 signedDataObjects,
-                signature);
+                signature,
+                idGenerator);
 
         /* ds:KeyInfo */
-        this.keyInfoBuilder.buildKeyInfo(signingCertificateChain, signature);
+        this.keyInfoBuilder.buildKeyInfo(signingCertificateChain, signature, idGenerator);
 
         /* QualifyingProperties element */
         // Create the QualifyingProperties element
@@ -239,6 +242,7 @@ public final XadesSignatureResult sign(
             // Marshal the signed properties data to the QualifyingProperties node.
             this.signedPropsMarshaller.marshal(signedPropsData, qualifyingPropsElem);
             Element signedPropsElem = DOMHelper.getFirstChildElement(qualifyingPropsElem);
+            String signedPropsId = idFor(signedPropsElem, idGenerator);
             DOMHelper.setIdAsXmlId(signedPropsElem, signedPropsId);
 
             // SignedProperties reference
@@ -285,7 +289,7 @@ public final XadesSignatureResult sign(
             Element sigValueElem = DOMHelper.getFirstDescendant(
                     signature.getElement(),
                     Constants.SignatureSpecNS, Constants._TAG_SIGNATUREVALUE);
-            DOMHelper.setIdAsXmlId(sigValueElem, String.format("%s-sigvalue", signatureId));
+            DOMHelper.setIdAsXmlId(sigValueElem, idFor(sigValueElem, idGenerator));
 
             /* Marshal unsigned properties */
             // Generate the unsigned properties data objects. The data objects structure
@@ -385,4 +389,14 @@ protected void getFormatSpecificSignatureProperties(
             formatSpecificSignedSigProps.add(scp);
         }
     }
+
+    public static String idFor(ElementProxy elementProxy, ElementIdGenerator idGenerator)
+    {
+        return idGenerator.generateId(elementProxy.getBaseNamespace(), elementProxy.getBaseLocalName());
+    }
+
+    public static String idFor(Element element, ElementIdGenerator idGenerator)
+    {
+        return idGenerator.generateId(element.getNamespaceURI(), element.getLocalName());
+    }
 }

src/main/java/xades4j/production/SignerC.java

@@ -59,9 +59,10 @@ protected SignerC(
             UnsignedPropertiesMarshaller unsignedPropsMarshaller,
             AlgorithmsParametersMarshallingProvider algorithmsParametersMarshaller,
             X500NameStyleProvider x500NameStyleProvider,
+            ElementIdGeneratorFactory idGeneratorFactory,
             Optional<SignaturePolicyInfoProvider> policyInfoProvider)
     {
-        super(keyingProvider, signatureAlgorithms, basicSignatureOptions, dataObjectDescsProcessor, signaturePropsProvider, dataObjPropsProvider, propsDataObjectsGenerator, signedPropsMarshaller, unsignedPropsMarshaller, algorithmsParametersMarshaller, x500NameStyleProvider, policyInfoProvider);
+        super(keyingProvider, signatureAlgorithms, basicSignatureOptions, dataObjectDescsProcessor, signaturePropsProvider, dataObjPropsProvider, propsDataObjectsGenerator, signedPropsMarshaller, unsignedPropsMarshaller, algorithmsParametersMarshaller, x500NameStyleProvider, idGeneratorFactory, policyInfoProvider);
         if (null == validationDataProvider)
             throw new NullPointerException("ValidationDataProvider is null");