Secure repository file paths and stream downloads (#1024)

* Secure repository file paths and stream downloads

Centralize repository file handling through FileRepositoryHelper for AAS
thumbnails, submodel attachments, and AASX packages. Uploaded logical
filenames are now validated as display names only, while stored repository
ids are generated server-side.

Stream thumbnail and attachment HTTP responses from the repository instead
of materializing repository ids as local filesystem paths. Keep legacy File
APIs compatible via safe temp-file/default fallbacks.

Update replacement/delete flows to update domain references safely and clean
up old repository entries after successful updates. Add regression coverage
for path traversal names, absolute repository keys, stream handling, and
authorization behavior.

* Fixes failing tests

Author: aaronzi

basyx.aasenvironment/basyx.aasenvironment-core/src/main/java/org/eclipse/digitaltwin/basyx/aasenvironment/base/DefaultAASEnvironment.java

@@ -371,7 +371,9 @@ private void handleFileError(File file) {
 
 
 	private byte[] getFileContent(String submodelId, File file) throws IOException {
-		return submodelRepository.getFileByFilePath(submodelId, file.getValue()).readAllBytes();
+		try (InputStream fileContent = submodelRepository.getFileByFilePath(submodelId, file.getValue())) {
+			return fileContent.readAllBytes();
+		}
 	}
 
 	private boolean isFileAlreadyAdded(String filePath){
@@ -386,7 +388,7 @@ private void addThumbnailToRelatedFiles(String aasId, Resource thumbnail, List<I
 				String newPath = getThumbnailPathInAASX(thumbnail.getPath());
 				relatedFiles.add(
 						new InMemoryFile(
-								Files.readAllBytes(aasRepository.getThumbnail(aasId).toPath()),
+								getThumbnailContent(aasId),
 								newPath
 						)
 				);
@@ -397,6 +399,25 @@ private void addThumbnailToRelatedFiles(String aasId, Resource thumbnail, List<I
 		}
 	}
 
+	private byte[] getThumbnailContent(String aasId) throws IOException {
+		try (InputStream thumbnailContent = aasRepository.getThumbnailInputStream(aasId)) {
+			return thumbnailContent.readAllBytes();
+		} catch (UnsupportedOperationException e) {
+			return getThumbnailContentFromFile(aasId);
+		}
+	}
+
+	private byte[] getThumbnailContentFromFile(String aasId) throws IOException {
+		java.io.File thumbnailFile = aasRepository.getThumbnail(aasId);
+
+		try {
+			return Files.readAllBytes(thumbnailFile.toPath());
+		} finally {
+			if (thumbnailFile != null)
+				thumbnailFile.delete();
+		}
+	}
+
 	private static boolean isThumbnailSet(Resource thumbnail) {
 		return thumbnail != null && thumbnail.getPath() != null;
 	}

basyx.aasrepository/basyx.aasrepository-backend/src/main/java/org/eclipse/digitaltwin/basyx/aasrepository/backend/CrudAasRepository.java

@@ -138,6 +138,11 @@ public File getThumbnail(String aasId) {
 		return getService(aasId).getThumbnail();
 	}
 
+	@Override
+	public InputStream getThumbnailInputStream(String aasId) {
+		return getService(aasId).getThumbnailInputStream();
+	}
+
 	@Override
 	public void setThumbnail(String aasId, String fileName, String contentType, InputStream inputStream) {
 		getService(aasId).setThumbnail(fileName, contentType, inputStream);

basyx.aasrepository/basyx.aasrepository-client/src/main/java/org/eclipse/digitaltwin/basyx/aasrepository/client/ConnectedAasRepository.java

@@ -181,6 +181,11 @@ public File getThumbnail(String aasId) {
 		return getConnectedAasService(aasId).getThumbnail();
 	}
 
+	@Override
+	public InputStream getThumbnailInputStream(String aasId) {
+		return getConnectedAasService(aasId).getThumbnailInputStream();
+	}
+
 	@Override
 	public void setThumbnail(String aasId, String fileName, String contentType, InputStream inputStream) {
 		getConnectedAasService(aasId).setThumbnail(fileName, contentType, inputStream);

basyx.aasrepository/basyx.aasrepository-core/src/main/java/org/eclipse/digitaltwin/basyx/aasrepository/AasRepository.java

@@ -1,30 +1,32 @@
 /*******************************************************************************
  * Copyright (C) 2023 the Eclipse BaSyx Authors
- * 
+ *
  * Permission is hereby granted, free of charge, to any person obtaining
  * a copy of this software and associated documentation files (the
  * "Software"), to deal in the Software without restriction, including
  * without limitation the rights to use, copy, modify, merge, publish,
  * distribute, sublicense, and/or sell copies of the Software, and to
  * permit persons to whom the Software is furnished to do so, subject to
  * the following conditions:
- * 
+ *
  * The above copyright notice and this permission notice shall be
  * included in all copies or substantial portions of the Software.
- * 
+ *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
- * 
+ *
  * SPDX-License-Identifier: MIT
  ******************************************************************************/
 package org.eclipse.digitaltwin.basyx.aasrepository;
 
 import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
 import java.io.InputStream;
 import java.util.List;
 
@@ -34,28 +36,29 @@
 import org.eclipse.digitaltwin.aas4j.v3.model.SpecificAssetId;
 import org.eclipse.digitaltwin.basyx.core.exceptions.CollidingIdentifierException;
 import org.eclipse.digitaltwin.basyx.core.exceptions.ElementDoesNotExistException;
+import org.eclipse.digitaltwin.basyx.core.exceptions.FileHandlingException;
 import org.eclipse.digitaltwin.basyx.core.exceptions.MissingIdentifierException;
 import org.eclipse.digitaltwin.basyx.core.pagination.CursorResult;
 import org.eclipse.digitaltwin.basyx.core.pagination.PaginationInfo;
 
 /**
  * Specifies the overall AasRepository API
- * 
+ *
  * @author schnicke, kammognie
  *
  */
 public interface AasRepository {
-	
+
 	/**
 	 * Retrieves all Asset Administration Shells from the repository
-	 * 
+	 *
 	 * @return a list of all found Asset Administration Shells
 	 */
 	public CursorResult<List<AssetAdministrationShell>> getAllAas(List<SpecificAssetId> assetIds, String idShort, PaginationInfo pInfo);
 
 	/**
 	 * Retrieves a specific AAS
-	 * 
+	 *
 	 * @param aasId
 	 *            the id of the AAS
 	 * @return the requested AAS
@@ -64,7 +67,7 @@ public interface AasRepository {
 
 	/**
 	 * Creates a new AAS at the endpoint
-	 * 
+	 *
 	 * @param aas
 	 *            the AAS to be created
 	 * @throws MissingIdentifierException
@@ -74,22 +77,22 @@ public interface AasRepository {
 
 	/**
 	 * Deletes a specific AAS
-	 * 
+	 *
 	 * @param aasId
 	 *            the id of the AAS to be deleted
 	 */
 	public void deleteAas(String aasId);
 
 	/**
 	 * Overwrites an existing AAS
-	 * 
+	 *
 	 * @param aas
 	 */
 	public void updateAas(String aasId, AssetAdministrationShell aas);
 
 	/**
 	 * Returns a List of References to Submodels
-	 * 
+	 *
 	 * @param aasId
 	 * @param pInfo
 	 * @return
@@ -98,48 +101,67 @@ public interface AasRepository {
 
 	/**
 	 * Adds a Submodel Reference
-	 * 
+	 *
 	 * @param submodelReference
 	 */
 	public void addSubmodelReference(String aasId, Reference submodelReference);
 
 	/**
 	 * Removes a Submodel Reference
-	 * 
+	 *
 	 * @param submodelId
 	 */
 	public void removeSubmodelReference(String aasId, String submodelId);
 
 	/**
 	 * Sets the asset-information of a specific AAS
-	 * 
+	 *
 	 * @param aasId
 	 *            the id of the AAS
 	 */
 	public void setAssetInformation(String aasId, AssetInformation aasInfo) throws ElementDoesNotExistException;
 
 	/**
 	 * Retrieves the asset-information of a specific AAS
-	 * 
+	 *
 	 * @param aasId
 	 *            the id of the AAS
-	 * 
+	 *
 	 * @return the requested AAS
 	 */
 	public AssetInformation getAssetInformation(String aasId) throws ElementDoesNotExistException;
 
 	/**
 	 * Get Thumbnail of the specific aas
-	 * 
+	 *
 	 * @param aasId
 	 *            the id of the AAS
 	 * @return the file of the thumbnail
 	 */
 	public File getThumbnail(String aasId);
 
+	/**
+	 * Get Thumbnail content of the specific aas as a stream
+	 * <p>
+	 * The caller is responsible for closing the returned stream.
+	 *
+	 * @param aasId
+	 *            the id of the AAS
+	 * @return the stream of the thumbnail
+	 * @throws org.eclipse.digitaltwin.basyx.core.exceptions.FileDoesNotExistException
+	 *             if no thumbnail is stored
+	 */
+	public default InputStream getThumbnailInputStream(String aasId) {
+		try {
+			return new FileInputStream(getThumbnail(aasId));
+		} catch (FileNotFoundException e) {
+			throw new FileHandlingException("Could not open thumbnail stream.", e);
+		}
+	}
+
 	/**
 	 * Set Thumbnail of the AAS
-	 * 
+	 *
 	 * @param aasId
 	 *            the id of the AAS
 	 * @param fileName
@@ -153,19 +175,19 @@ public interface AasRepository {
 
 	/**
 	 * Delete the thumbnail file of the AAS
-	 * 
+	 *
 	 * @param aasId
 	 *            the id of the AAS
 	 */
 	public void deleteThumbnail(String aasId);
-    
+
 	/**
 	 * Returns the name of the repository
-	 * 
+	 *
 	 * @return repoName
 	 */
 	public default String getName() {
 		return "aas-repo";
 	}
-	
+
 }

basyx.aasrepository/basyx.aasrepository-core/src/test/java/org/eclipse/digitaltwin/basyx/aasrepository/AasRepositoryAasServiceWrapper.java

@@ -88,6 +88,11 @@ public File getThumbnail() {
 		return repoApi.getThumbnail(aasId);
 	}
 
+	@Override
+	public InputStream getThumbnailInputStream() {
+		return repoApi.getThumbnailInputStream(aasId);
+	}
+
 	@Override
 	public void setThumbnail(String fileName, String contentType, InputStream inputStream) {
 		repoApi.setThumbnail(aasId, fileName, contentType, inputStream);